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btrfs: update kconfig title
[linux-2.6-block.git] / fs / btrfs / inode.c
CommitLineData
6cbd5570
CM		 1/*
2 * Copyright (C) 2007 Oracle. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
17 */
18
8f18cf13 19#include <linux/kernel.h>
065631f6 20#include <linux/bio.h>
39279cc3 21#include <linux/buffer_head.h>
f2eb0a24 22#include <linux/file.h>
39279cc3
CM		 23#include <linux/fs.h>
24#include <linux/pagemap.h>
25#include <linux/highmem.h>
26#include <linux/time.h>
27#include <linux/init.h>
28#include <linux/string.h>
39279cc3
CM		 29#include <linux/backing-dev.h>
30#include <linux/mpage.h>
31#include <linux/swap.h>
32#include <linux/writeback.h>
33#include <linux/statfs.h>
34#include <linux/compat.h>
9ebefb18 35#include <linux/bit_spinlock.h>
5103e947 36#include <linux/xattr.h>
33268eaf 37#include <linux/posix_acl.h>
d899e052 38#include <linux/falloc.h>
5a0e3ad6 39#include <linux/slab.h>
7a36ddec 40#include <linux/ratelimit.h>
22c44fe6 41#include <linux/mount.h>
55e301fd 42#include <linux/btrfs.h>
53b381b3 43#include <linux/blkdev.h>
4b4e25f2 44#include "compat.h"
39279cc3
CM		 45#include "ctree.h"
46#include "disk-io.h"
47#include "transaction.h"
48#include "btrfs_inode.h"
39279cc3 49#include "print-tree.h"
e6dcd2dc 50#include "ordered-data.h"
95819c05 51#include "xattr.h"
e02119d5 52#include "tree-log.h"
4a54c8c1 53#include "volumes.h"
c8b97818 54#include "compression.h"
b4ce94de 55#include "locking.h"
dc89e982 56#include "free-space-cache.h"
581bb050 57#include "inode-map.h"
38c227d8 58#include "backref.h"
39279cc3
CM		 59
60struct btrfs_iget_args {
61 u64 ino;
62 struct btrfs_root *root;
63};
64
6e1d5dcc
AD		 65static const struct inode_operations btrfs_dir_inode_operations;
66static const struct inode_operations btrfs_symlink_inode_operations;
67static const struct inode_operations btrfs_dir_ro_inode_operations;
68static const struct inode_operations btrfs_special_inode_operations;
69static const struct inode_operations btrfs_file_inode_operations;
7f09410b
AD		 70static const struct address_space_operations btrfs_aops;
71static const struct address_space_operations btrfs_symlink_aops;
828c0950 72static const struct file_operations btrfs_dir_file_operations;
d1310b2e 73static struct extent_io_ops btrfs_extent_io_ops;
39279cc3
CM		 74
75static struct kmem_cache *btrfs_inode_cachep;
8ccf6f19 76static struct kmem_cache *btrfs_delalloc_work_cachep;
39279cc3
CM		 77struct kmem_cache *btrfs_trans_handle_cachep;
78struct kmem_cache *btrfs_transaction_cachep;
39279cc3 79struct kmem_cache *btrfs_path_cachep;
dc89e982 80struct kmem_cache *btrfs_free_space_cachep;
39279cc3
CM		 81
82#define S_SHIFT 12
83static unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = {
84 [S_IFREG >> S_SHIFT] = BTRFS_FT_REG_FILE,
85 [S_IFDIR >> S_SHIFT] = BTRFS_FT_DIR,
86 [S_IFCHR >> S_SHIFT] = BTRFS_FT_CHRDEV,
87 [S_IFBLK >> S_SHIFT] = BTRFS_FT_BLKDEV,
88 [S_IFIFO >> S_SHIFT] = BTRFS_FT_FIFO,
89 [S_IFSOCK >> S_SHIFT] = BTRFS_FT_SOCK,
90 [S_IFLNK >> S_SHIFT] = BTRFS_FT_SYMLINK,
91};
92
3972f260 93static int btrfs_setsize(struct inode *inode, struct iattr *attr);
a41ad394 94static int btrfs_truncate(struct inode *inode);
5fd02043 95static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent);
771ed689
CM		 96static noinline int cow_file_range(struct inode *inode,
97 struct page *locked_page,
98 u64 start, u64 end, int *page_started,
99 unsigned long *nr_written, int unlock);
70c8a91c
JB		 100static struct extent_map *create_pinned_em(struct inode *inode, u64 start,
101 u64 len, u64 orig_start,
102 u64 block_start, u64 block_len,
103 u64 orig_block_len, int type);
7b128766 104
f34f57a3 105static int btrfs_init_inode_security(struct btrfs_trans_handle *trans,
2a7dba39
EP		 106 struct inode *inode, struct inode *dir,
107 const struct qstr *qstr)
0279b4cd
JO		 108{
109 int err;
110
f34f57a3 111 err = btrfs_init_acl(trans, inode, dir);
0279b4cd 112 if (!err)
2a7dba39 113 err = btrfs_xattr_security_init(trans, inode, dir, qstr);
0279b4cd
JO		 114 return err;
115}
116
c8b97818
CM		 117/*
118 * this does all the hard work for inserting an inline extent into
119 * the btree. The caller should have done a btrfs_drop_extents so that
120 * no overlapping inline items exist in the btree
121 */
d397712b 122static noinline int insert_inline_extent(struct btrfs_trans_handle *trans,
c8b97818
CM		 123 struct btrfs_root *root, struct inode *inode,
124 u64 start, size_t size, size_t compressed_size,
fe3f566c 125 int compress_type,
c8b97818
CM		 126 struct page **compressed_pages)
127{
128 struct btrfs_key key;
129 struct btrfs_path *path;
130 struct extent_buffer *leaf;
131 struct page *page = NULL;
132 char *kaddr;
133 unsigned long ptr;
134 struct btrfs_file_extent_item *ei;
135 int err = 0;
136 int ret;
137 size_t cur_size = size;
138 size_t datasize;
139 unsigned long offset;
c8b97818 140
fe3f566c 141 if (compressed_size && compressed_pages)
c8b97818 142 cur_size = compressed_size;
c8b97818 143
d397712b
CM		 144 path = btrfs_alloc_path();
145 if (!path)
c8b97818
CM		 146 return -ENOMEM;
147
b9473439 148 path->leave_spinning = 1;
c8b97818 149
33345d01 150 key.objectid = btrfs_ino(inode);
c8b97818
CM		 151 key.offset = start;
152 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
c8b97818
CM		 153 datasize = btrfs_file_extent_calc_inline_size(cur_size);
154
155 inode_add_bytes(inode, size);
156 ret = btrfs_insert_empty_item(trans, root, path, &key,
157 datasize);
c8b97818
CM		 158 if (ret) {
159 err = ret;
c8b97818
CM		 160 goto fail;
161 }
162 leaf = path->nodes[0];
163 ei = btrfs_item_ptr(leaf, path->slots[0],
164 struct btrfs_file_extent_item);
165 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
166 btrfs_set_file_extent_type(leaf, ei, BTRFS_FILE_EXTENT_INLINE);
167 btrfs_set_file_extent_encryption(leaf, ei, 0);
168 btrfs_set_file_extent_other_encoding(leaf, ei, 0);
169 btrfs_set_file_extent_ram_bytes(leaf, ei, size);
170 ptr = btrfs_file_extent_inline_start(ei);
171
261507a0 172 if (compress_type != BTRFS_COMPRESS_NONE) {
c8b97818
CM		 173 struct page *cpage;
174 int i = 0;
d397712b 175 while (compressed_size > 0) {
c8b97818 176 cpage = compressed_pages[i];
5b050f04 177 cur_size = min_t(unsigned long, compressed_size,
c8b97818
CM		 178 PAGE_CACHE_SIZE);
179
7ac687d9 180 kaddr = kmap_atomic(cpage);
c8b97818 181 write_extent_buffer(leaf, kaddr, ptr, cur_size);
7ac687d9 182 kunmap_atomic(kaddr);
c8b97818
CM		 183
184 i++;
185 ptr += cur_size;
186 compressed_size -= cur_size;
187 }
188 btrfs_set_file_extent_compression(leaf, ei,
261507a0 189 compress_type);
c8b97818
CM		 190 } else {
191 page = find_get_page(inode->i_mapping,
192 start >> PAGE_CACHE_SHIFT);
193 btrfs_set_file_extent_compression(leaf, ei, 0);
7ac687d9 194 kaddr = kmap_atomic(page);
c8b97818
CM		 195 offset = start & (PAGE_CACHE_SIZE - 1);
196 write_extent_buffer(leaf, kaddr + offset, ptr, size);
7ac687d9 197 kunmap_atomic(kaddr);
c8b97818
CM		 198 page_cache_release(page);
199 }
200 btrfs_mark_buffer_dirty(leaf);
201 btrfs_free_path(path);
202
c2167754
YZ		 203 /*
204 * we're an inline extent, so nobody can
205 * extend the file past i_size without locking
206 * a page we already have locked.
207 *
208 * We must do any isize and inode updates
209 * before we unlock the pages. Otherwise we
210 * could end up racing with unlink.
211 */
c8b97818 212 BTRFS_I(inode)->disk_i_size = inode->i_size;
79787eaa 213 ret = btrfs_update_inode(trans, root, inode);
c2167754 214
79787eaa 215 return ret;
c8b97818
CM		 216fail:
217 btrfs_free_path(path);
218 return err;
219}
220
221
222/*
223 * conditionally insert an inline extent into the file. This
224 * does the checks required to make sure the data is small enough
225 * to fit as an inline extent.
226 */
7f366cfe 227static noinline int cow_file_range_inline(struct btrfs_trans_handle *trans,
c8b97818
CM		 228 struct btrfs_root *root,
229 struct inode *inode, u64 start, u64 end,
fe3f566c 230 size_t compressed_size, int compress_type,
c8b97818
CM		 231 struct page **compressed_pages)
232{
233 u64 isize = i_size_read(inode);
234 u64 actual_end = min(end + 1, isize);
235 u64 inline_len = actual_end - start;
fda2832f 236 u64 aligned_end = ALIGN(end, root->sectorsize);
c8b97818
CM		 237 u64 data_len = inline_len;
238 int ret;
239
240 if (compressed_size)
241 data_len = compressed_size;
242
243 if (start > 0 ||
70b99e69 244 actual_end >= PAGE_CACHE_SIZE ||
c8b97818
CM		 245 data_len >= BTRFS_MAX_INLINE_DATA_SIZE(root) ||
246 (!compressed_size &&
247 (actual_end & (root->sectorsize - 1)) == 0) ||
248 end + 1 < isize ||
249 data_len > root->fs_info->max_inline) {
250 return 1;
251 }
252
2671485d 253 ret = btrfs_drop_extents(trans, root, inode, start, aligned_end, 1);
79787eaa
JM		 254 if (ret)
255 return ret;
c8b97818
CM		 256
257 if (isize > actual_end)
258 inline_len = min_t(u64, isize, actual_end);
259 ret = insert_inline_extent(trans, root, inode, start,
260 inline_len, compressed_size,
fe3f566c 261 compress_type, compressed_pages);
2adcac1a 262 if (ret && ret != -ENOSPC) {
79787eaa
JM		 263 btrfs_abort_transaction(trans, root, ret);
264 return ret;
2adcac1a
JB		 265 } else if (ret == -ENOSPC) {
266 return 1;
79787eaa 267 }
2adcac1a 268
bdc20e67 269 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags);
0ca1f7ce 270 btrfs_delalloc_release_metadata(inode, end + 1 - start);
a1ed835e 271 btrfs_drop_extent_cache(inode, start, aligned_end - 1, 0);
c8b97818
CM		 272 return 0;
273}
274
771ed689
CM		 275struct async_extent {
276 u64 start;
277 u64 ram_size;
278 u64 compressed_size;
279 struct page **pages;
280 unsigned long nr_pages;
261507a0 281 int compress_type;
771ed689
CM		 282 struct list_head list;
283};
284
285struct async_cow {
286 struct inode *inode;
287 struct btrfs_root *root;
288 struct page *locked_page;
289 u64 start;
290 u64 end;
291 struct list_head extents;
292 struct btrfs_work work;
293};
294
295static noinline int add_async_extent(struct async_cow *cow,
296 u64 start, u64 ram_size,
297 u64 compressed_size,
298 struct page **pages,
261507a0
LZ		 299 unsigned long nr_pages,
300 int compress_type)
771ed689
CM		 301{
302 struct async_extent *async_extent;
303
304 async_extent = kmalloc(sizeof(*async_extent), GFP_NOFS);
79787eaa 305 BUG_ON(!async_extent); /* -ENOMEM */
771ed689
CM		 306 async_extent->start = start;
307 async_extent->ram_size = ram_size;
308 async_extent->compressed_size = compressed_size;
309 async_extent->pages = pages;
310 async_extent->nr_pages = nr_pages;
261507a0 311 async_extent->compress_type = compress_type;
771ed689
CM		 312 list_add_tail(&async_extent->list, &cow->extents);
313 return 0;
314}
315
d352ac68 316/*
771ed689
CM		 317 * we create compressed extents in two phases. The first
318 * phase compresses a range of pages that have already been
319 * locked (both pages and state bits are locked).
c8b97818 320 *
771ed689
CM		 321 * This is done inside an ordered work queue, and the compression
322 * is spread across many cpus. The actual IO submission is step
323 * two, and the ordered work queue takes care of making sure that
324 * happens in the same order things were put onto the queue by
325 * writepages and friends.
c8b97818 326 *
771ed689
CM		 327 * If this code finds it can't get good compression, it puts an
328 * entry onto the work queue to write the uncompressed bytes. This
329 * makes sure that both compressed inodes and uncompressed inodes
b2570314
AB		 330 * are written in the same order that the flusher thread sent them
331 * down.
d352ac68 332 */
771ed689
CM		 333static noinline int compress_file_range(struct inode *inode,
334 struct page *locked_page,
335 u64 start, u64 end,
336 struct async_cow *async_cow,
337 int *num_added)
b888db2b
CM		 338{
339 struct btrfs_root *root = BTRFS_I(inode)->root;
340 struct btrfs_trans_handle *trans;
db94535d 341 u64 num_bytes;
db94535d 342 u64 blocksize = root->sectorsize;
c8b97818 343 u64 actual_end;
42dc7bab 344 u64 isize = i_size_read(inode);
e6dcd2dc 345 int ret = 0;
c8b97818
CM		 346 struct page **pages = NULL;
347 unsigned long nr_pages;
348 unsigned long nr_pages_ret = 0;
349 unsigned long total_compressed = 0;
350 unsigned long total_in = 0;
351 unsigned long max_compressed = 128 * 1024;
771ed689 352 unsigned long max_uncompressed = 128 * 1024;
c8b97818
CM		 353 int i;
354 int will_compress;
261507a0 355 int compress_type = root->fs_info->compress_type;
4adaa611 356 int redirty = 0;
b888db2b 357
4cb13e5d
LB		 358 /* if this is a small write inside eof, kick off a defrag */
359 if ((end - start + 1) < 16 * 1024 &&
360 (start > 0 || end + 1 < BTRFS_I(inode)->disk_i_size))
4cb5300b
CM		 361 btrfs_add_inode_defrag(NULL, inode);
362
42dc7bab 363 actual_end = min_t(u64, isize, end + 1);
c8b97818
CM		 364again:
365 will_compress = 0;
366 nr_pages = (end >> PAGE_CACHE_SHIFT) - (start >> PAGE_CACHE_SHIFT) + 1;
367 nr_pages = min(nr_pages, (128 * 1024UL) / PAGE_CACHE_SIZE);
be20aa9d 368
f03d9301
CM		 369 /*
370 * we don't want to send crud past the end of i_size through
371 * compression, that's just a waste of CPU time. So, if the
372 * end of the file is before the start of our current
373 * requested range of bytes, we bail out to the uncompressed
374 * cleanup code that can deal with all of this.
375 *
376 * It isn't really the fastest way to fix things, but this is a
377 * very uncommon corner.
378 */
379 if (actual_end <= start)
380 goto cleanup_and_bail_uncompressed;
381
c8b97818
CM		 382 total_compressed = actual_end - start;
383
384 /* we want to make sure that amount of ram required to uncompress
385 * an extent is reasonable, so we limit the total size in ram
771ed689
CM		 386 * of a compressed extent to 128k. This is a crucial number
387 * because it also controls how easily we can spread reads across
388 * cpus for decompression.
389 *
390 * We also want to make sure the amount of IO required to do
391 * a random read is reasonably small, so we limit the size of
392 * a compressed extent to 128k.
c8b97818
CM		 393 */
394 total_compressed = min(total_compressed, max_uncompressed);
fda2832f 395 num_bytes = ALIGN(end - start + 1, blocksize);
be20aa9d 396 num_bytes = max(blocksize, num_bytes);
c8b97818
CM		 397 total_in = 0;
398 ret = 0;
db94535d 399
771ed689
CM		 400 /*
401 * we do compression for mount -o compress and when the
402 * inode has not been flagged as nocompress. This flag can
403 * change at any time if we discover bad compression ratios.
c8b97818 404 */
6cbff00f 405 if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS) &&
1e701a32 406 (btrfs_test_opt(root, COMPRESS) ||
75e7cb7f
LB		 407 (BTRFS_I(inode)->force_compress) ||
408 (BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS))) {
c8b97818 409 WARN_ON(pages);
cfbc246e 410 pages = kzalloc(sizeof(struct page *) * nr_pages, GFP_NOFS);
560f7d75
LZ		 411 if (!pages) {
412 /* just bail out to the uncompressed code */
413 goto cont;
414 }
c8b97818 415
261507a0
LZ		 416 if (BTRFS_I(inode)->force_compress)
417 compress_type = BTRFS_I(inode)->force_compress;
418
4adaa611
CM		 419 /*
420 * we need to call clear_page_dirty_for_io on each
421 * page in the range. Otherwise applications with the file
422 * mmap'd can wander in and change the page contents while
423 * we are compressing them.
424 *
425 * If the compression fails for any reason, we set the pages
426 * dirty again later on.
427 */
428 extent_range_clear_dirty_for_io(inode, start, end);
429 redirty = 1;
261507a0
LZ		 430 ret = btrfs_compress_pages(compress_type,
431 inode->i_mapping, start,
432 total_compressed, pages,
433 nr_pages, &nr_pages_ret,
434 &total_in,
435 &total_compressed,
436 max_compressed);
c8b97818
CM		 437
438 if (!ret) {
439 unsigned long offset = total_compressed &
440 (PAGE_CACHE_SIZE - 1);
441 struct page *page = pages[nr_pages_ret - 1];
442 char *kaddr;
443
444 /* zero the tail end of the last page, we might be
445 * sending it down to disk
446 */
447 if (offset) {
7ac687d9 448 kaddr = kmap_atomic(page);
c8b97818
CM		 449 memset(kaddr + offset, 0,
450 PAGE_CACHE_SIZE - offset);
7ac687d9 451 kunmap_atomic(kaddr);
c8b97818
CM		 452 }
453 will_compress = 1;
454 }
455 }
560f7d75 456cont:
c8b97818 457 if (start == 0) {
7a7eaa40 458 trans = btrfs_join_transaction(root);
79787eaa
JM		 459 if (IS_ERR(trans)) {
460 ret = PTR_ERR(trans);
461 trans = NULL;
462 goto cleanup_and_out;
463 }
0ca1f7ce 464 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
771ed689 465
c8b97818 466 /* lets try to make an inline extent */
771ed689 467 if (ret || total_in < (actual_end - start)) {
c8b97818 468 /* we didn't compress the entire range, try
771ed689 469 * to make an uncompressed inline extent.
c8b97818
CM		 470 */
471 ret = cow_file_range_inline(trans, root, inode,
fe3f566c 472 start, end, 0, 0, NULL);
c8b97818 473 } else {
771ed689 474 /* try making a compressed inline extent */
c8b97818
CM		 475 ret = cow_file_range_inline(trans, root, inode,
476 start, end,
fe3f566c
LZ		 477 total_compressed,
478 compress_type, pages);
c8b97818 479 }
79787eaa 480 if (ret <= 0) {
771ed689 481 /*
79787eaa
JM		 482 * inline extent creation worked or returned error,
483 * we don't need to create any more async work items.
484 * Unlock and free up our temp pages.
771ed689 485 */
c8b97818 486 extent_clear_unlock_delalloc(inode,
a791e35e
CM		 487 &BTRFS_I(inode)->io_tree,
488 start, end, NULL,
489 EXTENT_CLEAR_UNLOCK_PAGE | EXTENT_CLEAR_DIRTY |
a3429ab7 490 EXTENT_CLEAR_DELALLOC |
a791e35e 491 EXTENT_SET_WRITEBACK | EXTENT_END_WRITEBACK);
c2167754
YZ		 492
493 btrfs_end_transaction(trans, root);
c8b97818
CM		 494 goto free_pages_out;
495 }
c2167754 496 btrfs_end_transaction(trans, root);
c8b97818
CM		 497 }
498
499 if (will_compress) {
500 /*
501 * we aren't doing an inline extent round the compressed size
502 * up to a block size boundary so the allocator does sane
503 * things
504 */
fda2832f 505 total_compressed = ALIGN(total_compressed, blocksize);
c8b97818
CM		 506
507 /*
508 * one last check to make sure the compression is really a
509 * win, compare the page count read with the blocks on disk
510 */
fda2832f 511 total_in = ALIGN(total_in, PAGE_CACHE_SIZE);
c8b97818
CM		 512 if (total_compressed >= total_in) {
513 will_compress = 0;
514 } else {
c8b97818
CM		 515 num_bytes = total_in;
516 }
517 }
518 if (!will_compress && pages) {
519 /*
520 * the compression code ran but failed to make things smaller,
521 * free any pages it allocated and our page pointer array
522 */
523 for (i = 0; i < nr_pages_ret; i++) {
70b99e69 524 WARN_ON(pages[i]->mapping);
c8b97818
CM		 525 page_cache_release(pages[i]);
526 }
527 kfree(pages);
528 pages = NULL;
529 total_compressed = 0;
530 nr_pages_ret = 0;
531
532 /* flag the file so we don't compress in the future */
1e701a32
CM		 533 if (!btrfs_test_opt(root, FORCE_COMPRESS) &&
534 !(BTRFS_I(inode)->force_compress)) {
a555f810 535 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
1e701a32 536 }
c8b97818 537 }
771ed689
CM		 538 if (will_compress) {
539 *num_added += 1;
c8b97818 540
771ed689
CM		 541 /* the async work queues will take care of doing actual
542 * allocation on disk for these compressed pages,
543 * and will submit them to the elevator.
544 */
545 add_async_extent(async_cow, start, num_bytes,
261507a0
LZ		 546 total_compressed, pages, nr_pages_ret,
547 compress_type);
179e29e4 548
24ae6365 549 if (start + num_bytes < end) {
771ed689
CM		 550 start += num_bytes;
551 pages = NULL;
552 cond_resched();
553 goto again;
554 }
555 } else {
f03d9301 556cleanup_and_bail_uncompressed:
771ed689
CM		 557 /*
558 * No compression, but we still need to write the pages in
559 * the file we've been given so far. redirty the locked
560 * page if it corresponds to our extent and set things up
561 * for the async work queue to run cow_file_range to do
562 * the normal delalloc dance
563 */
564 if (page_offset(locked_page) >= start &&
565 page_offset(locked_page) <= end) {
566 __set_page_dirty_nobuffers(locked_page);
567 /* unlocked later on in the async handlers */
568 }
4adaa611
CM		 569 if (redirty)
570 extent_range_redirty_for_io(inode, start, end);
261507a0
LZ		 571 add_async_extent(async_cow, start, end - start + 1,
572 0, NULL, 0, BTRFS_COMPRESS_NONE);
771ed689
CM		 573 *num_added += 1;
574 }
3b951516 575
771ed689 576out:
79787eaa 577 return ret;
771ed689
CM		 578
579free_pages_out:
580 for (i = 0; i < nr_pages_ret; i++) {
581 WARN_ON(pages[i]->mapping);
582 page_cache_release(pages[i]);
583 }
d397712b 584 kfree(pages);
771ed689
CM		 585
586 goto out;
79787eaa
JM		 587
588cleanup_and_out:
589 extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree,
590 start, end, NULL,
591 EXTENT_CLEAR_UNLOCK_PAGE |
592 EXTENT_CLEAR_DIRTY |
593 EXTENT_CLEAR_DELALLOC |
594 EXTENT_SET_WRITEBACK |
595 EXTENT_END_WRITEBACK);
596 if (!trans || IS_ERR(trans))
597 btrfs_error(root->fs_info, ret, "Failed to join transaction");
598 else
599 btrfs_abort_transaction(trans, root, ret);
600 goto free_pages_out;
771ed689
CM		 601}
602
603/*
604 * phase two of compressed writeback. This is the ordered portion
605 * of the code, which only gets called in the order the work was
606 * queued. We walk all the async extents created by compress_file_range
607 * and send them down to the disk.
608 */
609static noinline int submit_compressed_extents(struct inode *inode,
610 struct async_cow *async_cow)
611{
612 struct async_extent *async_extent;
613 u64 alloc_hint = 0;
614 struct btrfs_trans_handle *trans;
615 struct btrfs_key ins;
616 struct extent_map *em;
617 struct btrfs_root *root = BTRFS_I(inode)->root;
618 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
619 struct extent_io_tree *io_tree;
f5a84ee3 620 int ret = 0;
771ed689
CM		 621
622 if (list_empty(&async_cow->extents))
623 return 0;
624
3e04e7f1 625again:
d397712b 626 while (!list_empty(&async_cow->extents)) {
771ed689
CM		 627 async_extent = list_entry(async_cow->extents.next,
628 struct async_extent, list);
629 list_del(&async_extent->list);
c8b97818 630
771ed689
CM		 631 io_tree = &BTRFS_I(inode)->io_tree;
632
f5a84ee3 633retry:
771ed689
CM		 634 /* did the compression code fall back to uncompressed IO? */
635 if (!async_extent->pages) {
636 int page_started = 0;
637 unsigned long nr_written = 0;
638
639 lock_extent(io_tree, async_extent->start,
2ac55d41 640 async_extent->start +
d0082371 641 async_extent->ram_size - 1);
771ed689
CM		 642
643 /* allocate blocks */
f5a84ee3
JB		 644 ret = cow_file_range(inode, async_cow->locked_page,
645 async_extent->start,
646 async_extent->start +
647 async_extent->ram_size - 1,
648 &page_started, &nr_written, 0);
771ed689 649
79787eaa
JM		 650 /* JDM XXX */
651
771ed689
CM		 652 /*
653 * if page_started, cow_file_range inserted an
654 * inline extent and took care of all the unlocking
655 * and IO for us. Otherwise, we need to submit
656 * all those pages down to the drive.
657 */
f5a84ee3 658 if (!page_started && !ret)
771ed689
CM		 659 extent_write_locked_range(io_tree,
660 inode, async_extent->start,
d397712b 661 async_extent->start +
771ed689
CM		 662 async_extent->ram_size - 1,
663 btrfs_get_extent,
664 WB_SYNC_ALL);
3e04e7f1
JB		 665 else if (ret)
666 unlock_page(async_cow->locked_page);
771ed689
CM		 667 kfree(async_extent);
668 cond_resched();
669 continue;
670 }
671
672 lock_extent(io_tree, async_extent->start,
d0082371 673 async_extent->start + async_extent->ram_size - 1);
771ed689 674
7a7eaa40 675 trans = btrfs_join_transaction(root);
79787eaa
JM		 676 if (IS_ERR(trans)) {
677 ret = PTR_ERR(trans);
678 } else {
679 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
680 ret = btrfs_reserve_extent(trans, root,
771ed689
CM		 681 async_extent->compressed_size,
682 async_extent->compressed_size,
81c9ad23 683 0, alloc_hint, &ins, 1);
962197ba 684 if (ret && ret != -ENOSPC)
79787eaa
JM		 685 btrfs_abort_transaction(trans, root, ret);
686 btrfs_end_transaction(trans, root);
687 }
c2167754 688
f5a84ee3
JB		 689 if (ret) {
690 int i;
3e04e7f1 691
f5a84ee3
JB		 692 for (i = 0; i < async_extent->nr_pages; i++) {
693 WARN_ON(async_extent->pages[i]->mapping);
694 page_cache_release(async_extent->pages[i]);
695 }
696 kfree(async_extent->pages);
697 async_extent->nr_pages = 0;
698 async_extent->pages = NULL;
3e04e7f1 699
79787eaa
JM		 700 if (ret == -ENOSPC)
701 goto retry;
3e04e7f1 702 goto out_free;
f5a84ee3
JB		 703 }
704
c2167754
YZ		 705 /*
706 * here we're doing allocation and writeback of the
707 * compressed pages
708 */
709 btrfs_drop_extent_cache(inode, async_extent->start,
710 async_extent->start +
711 async_extent->ram_size - 1, 0);
712
172ddd60 713 em = alloc_extent_map();
3e04e7f1
JB		 714 if (!em)
715 goto out_free_reserve;
771ed689
CM		 716 em->start = async_extent->start;
717 em->len = async_extent->ram_size;
445a6944 718 em->orig_start = em->start;
2ab28f32
JB		 719 em->mod_start = em->start;
720 em->mod_len = em->len;
c8b97818 721
771ed689
CM		 722 em->block_start = ins.objectid;
723 em->block_len = ins.offset;
b4939680 724 em->orig_block_len = ins.offset;
771ed689 725 em->bdev = root->fs_info->fs_devices->latest_bdev;
261507a0 726 em->compress_type = async_extent->compress_type;
771ed689
CM		 727 set_bit(EXTENT_FLAG_PINNED, &em->flags);
728 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
70c8a91c 729 em->generation = -1;
771ed689 730
d397712b 731 while (1) {
890871be 732 write_lock(&em_tree->lock);
771ed689 733 ret = add_extent_mapping(em_tree, em);
70c8a91c
JB		 734 if (!ret)
735 list_move(&em->list,
736 &em_tree->modified_extents);
890871be 737 write_unlock(&em_tree->lock);
771ed689
CM		 738 if (ret != -EEXIST) {
739 free_extent_map(em);
740 break;
741 }
742 btrfs_drop_extent_cache(inode, async_extent->start,
743 async_extent->start +
744 async_extent->ram_size - 1, 0);
745 }
746
3e04e7f1
JB		 747 if (ret)
748 goto out_free_reserve;
749
261507a0
LZ		 750 ret = btrfs_add_ordered_extent_compress(inode,
751 async_extent->start,
752 ins.objectid,
753 async_extent->ram_size,
754 ins.offset,
755 BTRFS_ORDERED_COMPRESSED,
756 async_extent->compress_type);
3e04e7f1
JB		 757 if (ret)
758 goto out_free_reserve;
771ed689 759
771ed689
CM		 760 /*
761 * clear dirty, set writeback and unlock the pages.
762 */
763 extent_clear_unlock_delalloc(inode,
a791e35e
CM		 764 &BTRFS_I(inode)->io_tree,
765 async_extent->start,
766 async_extent->start +
767 async_extent->ram_size - 1,
768 NULL, EXTENT_CLEAR_UNLOCK_PAGE |
769 EXTENT_CLEAR_UNLOCK |
a3429ab7 770 EXTENT_CLEAR_DELALLOC |
a791e35e 771 EXTENT_CLEAR_DIRTY | EXTENT_SET_WRITEBACK);
771ed689
CM		 772
773 ret = btrfs_submit_compressed_write(inode,
d397712b
CM		 774 async_extent->start,
775 async_extent->ram_size,
776 ins.objectid,
777 ins.offset, async_extent->pages,
778 async_extent->nr_pages);
771ed689
CM		 779 alloc_hint = ins.objectid + ins.offset;
780 kfree(async_extent);
3e04e7f1
JB		 781 if (ret)
782 goto out;
771ed689
CM		 783 cond_resched();
784 }
79787eaa
JM		 785 ret = 0;
786out:
787 return ret;
3e04e7f1
JB		 788out_free_reserve:
789 btrfs_free_reserved_extent(root, ins.objectid, ins.offset);
79787eaa 790out_free:
3e04e7f1
JB		 791 extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree,
792 async_extent->start,
793 async_extent->start +
794 async_extent->ram_size - 1,
795 NULL, EXTENT_CLEAR_UNLOCK_PAGE |
796 EXTENT_CLEAR_UNLOCK |
797 EXTENT_CLEAR_DELALLOC |
798 EXTENT_CLEAR_DIRTY |
799 EXTENT_SET_WRITEBACK |
800 EXTENT_END_WRITEBACK);
79787eaa 801 kfree(async_extent);
3e04e7f1 802 goto again;
771ed689
CM		 803}
804
4b46fce2
JB		 805static u64 get_extent_allocation_hint(struct inode *inode, u64 start,
806 u64 num_bytes)
807{
808 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
809 struct extent_map *em;
810 u64 alloc_hint = 0;
811
812 read_lock(&em_tree->lock);
813 em = search_extent_mapping(em_tree, start, num_bytes);
814 if (em) {
815 /*
816 * if block start isn't an actual block number then find the
817 * first block in this inode and use that as a hint. If that
818 * block is also bogus then just don't worry about it.
819 */
820 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
821 free_extent_map(em);
822 em = search_extent_mapping(em_tree, 0, 0);
823 if (em && em->block_start < EXTENT_MAP_LAST_BYTE)
824 alloc_hint = em->block_start;
825 if (em)
826 free_extent_map(em);
827 } else {
828 alloc_hint = em->block_start;
829 free_extent_map(em);
830 }
831 }
832 read_unlock(&em_tree->lock);
833
834 return alloc_hint;
835}
836
771ed689
CM		 837/*
838 * when extent_io.c finds a delayed allocation range in the file,
839 * the call backs end up in this code. The basic idea is to
840 * allocate extents on disk for the range, and create ordered data structs
841 * in ram to track those extents.
842 *
843 * locked_page is the page that writepage had locked already. We use
844 * it to make sure we don't do extra locks or unlocks.
845 *
846 * *page_started is set to one if we unlock locked_page and do everything
847 * required to start IO on it. It may be clean and already done with
848 * IO when we return.
849 */
b7d5b0a8
MX		 850static noinline int __cow_file_range(struct btrfs_trans_handle *trans,
851 struct inode *inode,
852 struct btrfs_root *root,
853 struct page *locked_page,
854 u64 start, u64 end, int *page_started,
855 unsigned long *nr_written,
856 int unlock)
771ed689 857{
771ed689
CM		 858 u64 alloc_hint = 0;
859 u64 num_bytes;
860 unsigned long ram_size;
861 u64 disk_num_bytes;
862 u64 cur_alloc_size;
863 u64 blocksize = root->sectorsize;
771ed689
CM		 864 struct btrfs_key ins;
865 struct extent_map *em;
866 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
867 int ret = 0;
868
83eea1f1 869 BUG_ON(btrfs_is_free_space_inode(inode));
771ed689 870
fda2832f 871 num_bytes = ALIGN(end - start + 1, blocksize);
771ed689
CM		 872 num_bytes = max(blocksize, num_bytes);
873 disk_num_bytes = num_bytes;
771ed689 874
4cb5300b 875 /* if this is a small write inside eof, kick off defrag */
4cb13e5d
LB		 876 if (num_bytes < 64 * 1024 &&
877 (start > 0 || end + 1 < BTRFS_I(inode)->disk_i_size))
4cb5300b
CM		 878 btrfs_add_inode_defrag(trans, inode);
879
771ed689
CM		 880 if (start == 0) {
881 /* lets try to make an inline extent */
882 ret = cow_file_range_inline(trans, root, inode,
fe3f566c 883 start, end, 0, 0, NULL);
771ed689
CM		 884 if (ret == 0) {
885 extent_clear_unlock_delalloc(inode,
a791e35e
CM		 886 &BTRFS_I(inode)->io_tree,
887 start, end, NULL,
888 EXTENT_CLEAR_UNLOCK_PAGE |
889 EXTENT_CLEAR_UNLOCK |
890 EXTENT_CLEAR_DELALLOC |
891 EXTENT_CLEAR_DIRTY |
892 EXTENT_SET_WRITEBACK |
893 EXTENT_END_WRITEBACK);
c2167754 894
771ed689
CM		 895 *nr_written = *nr_written +
896 (end - start + PAGE_CACHE_SIZE) / PAGE_CACHE_SIZE;
897 *page_started = 1;
771ed689 898 goto out;
79787eaa
JM		 899 } else if (ret < 0) {
900 btrfs_abort_transaction(trans, root, ret);
901 goto out_unlock;
771ed689
CM		 902 }
903 }
904
905 BUG_ON(disk_num_bytes >
6c41761f 906 btrfs_super_total_bytes(root->fs_info->super_copy));
771ed689 907
4b46fce2 908 alloc_hint = get_extent_allocation_hint(inode, start, num_bytes);
771ed689
CM		 909 btrfs_drop_extent_cache(inode, start, start + num_bytes - 1, 0);
910
d397712b 911 while (disk_num_bytes > 0) {
a791e35e
CM		 912 unsigned long op;
913
287a0ab9 914 cur_alloc_size = disk_num_bytes;
e6dcd2dc 915 ret = btrfs_reserve_extent(trans, root, cur_alloc_size,
771ed689 916 root->sectorsize, 0, alloc_hint,
81c9ad23 917 &ins, 1);
79787eaa
JM		 918 if (ret < 0) {
919 btrfs_abort_transaction(trans, root, ret);
920 goto out_unlock;
921 }
d397712b 922
172ddd60 923 em = alloc_extent_map();
79787eaa 924 BUG_ON(!em); /* -ENOMEM */
e6dcd2dc 925 em->start = start;
445a6944 926 em->orig_start = em->start;
771ed689
CM		 927 ram_size = ins.offset;
928 em->len = ins.offset;
2ab28f32
JB		 929 em->mod_start = em->start;
930 em->mod_len = em->len;
c8b97818 931
e6dcd2dc 932 em->block_start = ins.objectid;
c8b97818 933 em->block_len = ins.offset;
b4939680 934 em->orig_block_len = ins.offset;
e6dcd2dc 935 em->bdev = root->fs_info->fs_devices->latest_bdev;
7f3c74fb 936 set_bit(EXTENT_FLAG_PINNED, &em->flags);
70c8a91c 937 em->generation = -1;
c8b97818 938
d397712b 939 while (1) {
890871be 940 write_lock(&em_tree->lock);
e6dcd2dc 941 ret = add_extent_mapping(em_tree, em);
70c8a91c
JB		 942 if (!ret)
943 list_move(&em->list,
944 &em_tree->modified_extents);
890871be 945 write_unlock(&em_tree->lock);
e6dcd2dc
CM		 946 if (ret != -EEXIST) {
947 free_extent_map(em);
948 break;
949 }
950 btrfs_drop_extent_cache(inode, start,
c8b97818 951 start + ram_size - 1, 0);
e6dcd2dc
CM		 952 }
953
98d20f67 954 cur_alloc_size = ins.offset;
e6dcd2dc 955 ret = btrfs_add_ordered_extent(inode, start, ins.objectid,
771ed689 956 ram_size, cur_alloc_size, 0);
79787eaa 957 BUG_ON(ret); /* -ENOMEM */
c8b97818 958
17d217fe
YZ		 959 if (root->root_key.objectid ==
960 BTRFS_DATA_RELOC_TREE_OBJECTID) {
961 ret = btrfs_reloc_clone_csums(inode, start,
962 cur_alloc_size);
79787eaa
JM		 963 if (ret) {
964 btrfs_abort_transaction(trans, root, ret);
965 goto out_unlock;
966 }
17d217fe
YZ		 967 }
968
d397712b 969 if (disk_num_bytes < cur_alloc_size)
3b951516 970 break;
d397712b 971
c8b97818
CM		 972 /* we're not doing compressed IO, don't unlock the first
973 * page (which the caller expects to stay locked), don't
974 * clear any dirty bits and don't set any writeback bits
8b62b72b
CM		 975 *
976 * Do set the Private2 bit so we know this page was properly
977 * setup for writepage
c8b97818 978 */
a791e35e
CM		 979 op = unlock ? EXTENT_CLEAR_UNLOCK_PAGE : 0;
980 op |= EXTENT_CLEAR_UNLOCK | EXTENT_CLEAR_DELALLOC |
981 EXTENT_SET_PRIVATE2;
982
c8b97818
CM		 983 extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree,
984 start, start + ram_size - 1,
a791e35e 985 locked_page, op);
c8b97818 986 disk_num_bytes -= cur_alloc_size;
c59f8951
CM		 987 num_bytes -= cur_alloc_size;
988 alloc_hint = ins.objectid + ins.offset;
989 start += cur_alloc_size;
b888db2b 990 }
79787eaa 991out:
be20aa9d 992 return ret;
b7d5b0a8 993
79787eaa
JM		 994out_unlock:
995 extent_clear_unlock_delalloc(inode,
996 &BTRFS_I(inode)->io_tree,
beb42dd7 997 start, end, locked_page,
79787eaa
JM		 998 EXTENT_CLEAR_UNLOCK_PAGE |
999 EXTENT_CLEAR_UNLOCK |
1000 EXTENT_CLEAR_DELALLOC |
1001 EXTENT_CLEAR_DIRTY |
1002 EXTENT_SET_WRITEBACK |
1003 EXTENT_END_WRITEBACK);
1004
1005 goto out;
771ed689 1006}
c8b97818 1007
b7d5b0a8
MX		 1008static noinline int cow_file_range(struct inode *inode,
1009 struct page *locked_page,
1010 u64 start, u64 end, int *page_started,
1011 unsigned long *nr_written,
1012 int unlock)
1013{
1014 struct btrfs_trans_handle *trans;
1015 struct btrfs_root *root = BTRFS_I(inode)->root;
1016 int ret;
1017
1018 trans = btrfs_join_transaction(root);
1019 if (IS_ERR(trans)) {
1020 extent_clear_unlock_delalloc(inode,
1021 &BTRFS_I(inode)->io_tree,
1022 start, end, locked_page,
1023 EXTENT_CLEAR_UNLOCK_PAGE |
1024 EXTENT_CLEAR_UNLOCK |
1025 EXTENT_CLEAR_DELALLOC |
1026 EXTENT_CLEAR_DIRTY |
1027 EXTENT_SET_WRITEBACK |
1028 EXTENT_END_WRITEBACK);
1029 return PTR_ERR(trans);
1030 }
1031 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
1032
1033 ret = __cow_file_range(trans, inode, root, locked_page, start, end,
1034 page_started, nr_written, unlock);
1035
1036 btrfs_end_transaction(trans, root);
1037
1038 return ret;
1039}
1040
771ed689
CM		 1041/*
1042 * work queue call back to started compression on a file and pages
1043 */
1044static noinline void async_cow_start(struct btrfs_work *work)
1045{
1046 struct async_cow *async_cow;
1047 int num_added = 0;
1048 async_cow = container_of(work, struct async_cow, work);
1049
1050 compress_file_range(async_cow->inode, async_cow->locked_page,
1051 async_cow->start, async_cow->end, async_cow,
1052 &num_added);
8180ef88 1053 if (num_added == 0) {
cb77fcd8 1054 btrfs_add_delayed_iput(async_cow->inode);
771ed689 1055 async_cow->inode = NULL;
8180ef88 1056 }
771ed689
CM		 1057}
1058
1059/*
1060 * work queue call back to submit previously compressed pages
1061 */
1062static noinline void async_cow_submit(struct btrfs_work *work)
1063{
1064 struct async_cow *async_cow;
1065 struct btrfs_root *root;
1066 unsigned long nr_pages;
1067
1068 async_cow = container_of(work, struct async_cow, work);
1069
1070 root = async_cow->root;
1071 nr_pages = (async_cow->end - async_cow->start + PAGE_CACHE_SIZE) >>
1072 PAGE_CACHE_SHIFT;
1073
66657b31 1074 if (atomic_sub_return(nr_pages, &root->fs_info->async_delalloc_pages) <
287082b0 1075 5 * 1024 * 1024 &&
771ed689
CM		 1076 waitqueue_active(&root->fs_info->async_submit_wait))
1077 wake_up(&root->fs_info->async_submit_wait);
1078
d397712b 1079 if (async_cow->inode)
771ed689 1080 submit_compressed_extents(async_cow->inode, async_cow);
771ed689 1081}
c8b97818 1082
771ed689
CM		 1083static noinline void async_cow_free(struct btrfs_work *work)
1084{
1085 struct async_cow *async_cow;
1086 async_cow = container_of(work, struct async_cow, work);
8180ef88 1087 if (async_cow->inode)
cb77fcd8 1088 btrfs_add_delayed_iput(async_cow->inode);
771ed689
CM		 1089 kfree(async_cow);
1090}
1091
1092static int cow_file_range_async(struct inode *inode, struct page *locked_page,
1093 u64 start, u64 end, int *page_started,
1094 unsigned long *nr_written)
1095{
1096 struct async_cow *async_cow;
1097 struct btrfs_root *root = BTRFS_I(inode)->root;
1098 unsigned long nr_pages;
1099 u64 cur_end;
287082b0 1100 int limit = 10 * 1024 * 1024;
771ed689 1101
a3429ab7
CM		 1102 clear_extent_bit(&BTRFS_I(inode)->io_tree, start, end, EXTENT_LOCKED,
1103 1, 0, NULL, GFP_NOFS);
d397712b 1104 while (start < end) {
771ed689 1105 async_cow = kmalloc(sizeof(*async_cow), GFP_NOFS);
79787eaa 1106 BUG_ON(!async_cow); /* -ENOMEM */
8180ef88 1107 async_cow->inode = igrab(inode);
771ed689
CM		 1108 async_cow->root = root;
1109 async_cow->locked_page = locked_page;
1110 async_cow->start = start;
1111
6cbff00f 1112 if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS)
771ed689
CM		 1113 cur_end = end;
1114 else
1115 cur_end = min(end, start + 512 * 1024 - 1);
1116
1117 async_cow->end = cur_end;
1118 INIT_LIST_HEAD(&async_cow->extents);
1119
1120 async_cow->work.func = async_cow_start;
1121 async_cow->work.ordered_func = async_cow_submit;
1122 async_cow->work.ordered_free = async_cow_free;
1123 async_cow->work.flags = 0;
1124
771ed689
CM		 1125 nr_pages = (cur_end - start + PAGE_CACHE_SIZE) >>
1126 PAGE_CACHE_SHIFT;
1127 atomic_add(nr_pages, &root->fs_info->async_delalloc_pages);
1128
1129 btrfs_queue_worker(&root->fs_info->delalloc_workers,
1130 &async_cow->work);
1131
1132 if (atomic_read(&root->fs_info->async_delalloc_pages) > limit) {
1133 wait_event(root->fs_info->async_submit_wait,
1134 (atomic_read(&root->fs_info->async_delalloc_pages) <
1135 limit));
1136 }
1137
d397712b 1138 while (atomic_read(&root->fs_info->async_submit_draining) &&
771ed689
CM		 1139 atomic_read(&root->fs_info->async_delalloc_pages)) {
1140 wait_event(root->fs_info->async_submit_wait,
1141 (atomic_read(&root->fs_info->async_delalloc_pages) ==
1142 0));
1143 }
1144
1145 *nr_written += nr_pages;
1146 start = cur_end + 1;
1147 }
1148 *page_started = 1;
1149 return 0;
be20aa9d
CM		 1150}
1151
d397712b 1152static noinline int csum_exist_in_range(struct btrfs_root *root,
17d217fe
YZ		 1153 u64 bytenr, u64 num_bytes)
1154{
1155 int ret;
1156 struct btrfs_ordered_sum *sums;
1157 LIST_HEAD(list);
1158
07d400a6 1159 ret = btrfs_lookup_csums_range(root->fs_info->csum_root, bytenr,
a2de733c 1160 bytenr + num_bytes - 1, &list, 0);
17d217fe
YZ		 1161 if (ret == 0 && list_empty(&list))
1162 return 0;
1163
1164 while (!list_empty(&list)) {
1165 sums = list_entry(list.next, struct btrfs_ordered_sum, list);
1166 list_del(&sums->list);
1167 kfree(sums);
1168 }
1169 return 1;
1170}
1171
d352ac68
CM		 1172/*
1173 * when nowcow writeback call back. This checks for snapshots or COW copies
1174 * of the extents that exist in the file, and COWs the file as required.
1175 *
1176 * If no cow copies or snapshots exist, we write directly to the existing
1177 * blocks on disk
1178 */
7f366cfe
CM		 1179static noinline int run_delalloc_nocow(struct inode *inode,
1180 struct page *locked_page,
771ed689
CM		 1181 u64 start, u64 end, int *page_started, int force,
1182 unsigned long *nr_written)
be20aa9d 1183{
be20aa9d 1184 struct btrfs_root *root = BTRFS_I(inode)->root;
7ea394f1 1185 struct btrfs_trans_handle *trans;
be20aa9d 1186 struct extent_buffer *leaf;
be20aa9d 1187 struct btrfs_path *path;
80ff3856 1188 struct btrfs_file_extent_item *fi;
be20aa9d 1189 struct btrfs_key found_key;
80ff3856
YZ		 1190 u64 cow_start;
1191 u64 cur_offset;
1192 u64 extent_end;
5d4f98a2 1193 u64 extent_offset;
80ff3856
YZ		 1194 u64 disk_bytenr;
1195 u64 num_bytes;
b4939680 1196 u64 disk_num_bytes;
80ff3856 1197 int extent_type;
79787eaa 1198 int ret, err;
d899e052 1199 int type;
80ff3856
YZ		 1200 int nocow;
1201 int check_prev = 1;
82d5902d 1202 bool nolock;
33345d01 1203 u64 ino = btrfs_ino(inode);
be20aa9d
CM		 1204
1205 path = btrfs_alloc_path();
17ca04af
JB		 1206 if (!path) {
1207 extent_clear_unlock_delalloc(inode,
1208 &BTRFS_I(inode)->io_tree,
1209 start, end, locked_page,
1210 EXTENT_CLEAR_UNLOCK_PAGE |
1211 EXTENT_CLEAR_UNLOCK |
1212 EXTENT_CLEAR_DELALLOC |
1213 EXTENT_CLEAR_DIRTY |
1214 EXTENT_SET_WRITEBACK |
1215 EXTENT_END_WRITEBACK);
d8926bb3 1216 return -ENOMEM;
17ca04af 1217 }
82d5902d 1218
83eea1f1 1219 nolock = btrfs_is_free_space_inode(inode);
82d5902d
LZ		 1220
1221 if (nolock)
7a7eaa40 1222 trans = btrfs_join_transaction_nolock(root);
82d5902d 1223 else
7a7eaa40 1224 trans = btrfs_join_transaction(root);
ff5714cc 1225
79787eaa 1226 if (IS_ERR(trans)) {
17ca04af
JB		 1227 extent_clear_unlock_delalloc(inode,
1228 &BTRFS_I(inode)->io_tree,
1229 start, end, locked_page,
1230 EXTENT_CLEAR_UNLOCK_PAGE |
1231 EXTENT_CLEAR_UNLOCK |
1232 EXTENT_CLEAR_DELALLOC |
1233 EXTENT_CLEAR_DIRTY |
1234 EXTENT_SET_WRITEBACK |
1235 EXTENT_END_WRITEBACK);
79787eaa
JM		 1236 btrfs_free_path(path);
1237 return PTR_ERR(trans);
1238 }
1239
74b21075 1240 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
be20aa9d 1241
80ff3856
YZ		 1242 cow_start = (u64)-1;
1243 cur_offset = start;
1244 while (1) {
33345d01 1245 ret = btrfs_lookup_file_extent(trans, root, path, ino,
80ff3856 1246 cur_offset, 0);
79787eaa
JM		 1247 if (ret < 0) {
1248 btrfs_abort_transaction(trans, root, ret);
1249 goto error;
1250 }
80ff3856
YZ		 1251 if (ret > 0 && path->slots[0] > 0 && check_prev) {
1252 leaf = path->nodes[0];
1253 btrfs_item_key_to_cpu(leaf, &found_key,
1254 path->slots[0] - 1);
33345d01 1255 if (found_key.objectid == ino &&
80ff3856
YZ		 1256 found_key.type == BTRFS_EXTENT_DATA_KEY)
1257 path->slots[0]--;
1258 }
1259 check_prev = 0;
1260next_slot:
1261 leaf = path->nodes[0];
1262 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
1263 ret = btrfs_next_leaf(root, path);
79787eaa
JM		 1264 if (ret < 0) {
1265 btrfs_abort_transaction(trans, root, ret);
1266 goto error;
1267 }
80ff3856
YZ		 1268 if (ret > 0)
1269 break;
1270 leaf = path->nodes[0];
1271 }
be20aa9d 1272
80ff3856
YZ		 1273 nocow = 0;
1274 disk_bytenr = 0;
17d217fe 1275 num_bytes = 0;
80ff3856
YZ		 1276 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1277
33345d01 1278 if (found_key.objectid > ino ||
80ff3856
YZ		 1279 found_key.type > BTRFS_EXTENT_DATA_KEY ||
1280 found_key.offset > end)
1281 break;
1282
1283 if (found_key.offset > cur_offset) {
1284 extent_end = found_key.offset;
e9061e21 1285 extent_type = 0;
80ff3856
YZ		 1286 goto out_check;
1287 }
1288
1289 fi = btrfs_item_ptr(leaf, path->slots[0],
1290 struct btrfs_file_extent_item);
1291 extent_type = btrfs_file_extent_type(leaf, fi);
1292
d899e052
YZ		 1293 if (extent_type == BTRFS_FILE_EXTENT_REG ||
1294 extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
80ff3856 1295 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
5d4f98a2 1296 extent_offset = btrfs_file_extent_offset(leaf, fi);
80ff3856
YZ		 1297 extent_end = found_key.offset +
1298 btrfs_file_extent_num_bytes(leaf, fi);
b4939680
JB		 1299 disk_num_bytes =
1300 btrfs_file_extent_disk_num_bytes(leaf, fi);
80ff3856
YZ		 1301 if (extent_end <= start) {
1302 path->slots[0]++;
1303 goto next_slot;
1304 }
17d217fe
YZ		 1305 if (disk_bytenr == 0)
1306 goto out_check;
80ff3856
YZ		 1307 if (btrfs_file_extent_compression(leaf, fi) ||
1308 btrfs_file_extent_encryption(leaf, fi) ||
1309 btrfs_file_extent_other_encoding(leaf, fi))
1310 goto out_check;
d899e052
YZ		 1311 if (extent_type == BTRFS_FILE_EXTENT_REG && !force)
1312 goto out_check;
d2fb3437 1313 if (btrfs_extent_readonly(root, disk_bytenr))
80ff3856 1314 goto out_check;
33345d01 1315 if (btrfs_cross_ref_exist(trans, root, ino,
5d4f98a2
YZ		 1316 found_key.offset -
1317 extent_offset, disk_bytenr))
17d217fe 1318 goto out_check;
5d4f98a2 1319 disk_bytenr += extent_offset;
17d217fe
YZ		 1320 disk_bytenr += cur_offset - found_key.offset;
1321 num_bytes = min(end + 1, extent_end) - cur_offset;
1322 /*
1323 * force cow if csum exists in the range.
1324 * this ensure that csum for a given extent are
1325 * either valid or do not exist.
1326 */
1327 if (csum_exist_in_range(root, disk_bytenr, num_bytes))
1328 goto out_check;
80ff3856
YZ		 1329 nocow = 1;
1330 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
1331 extent_end = found_key.offset +
1332 btrfs_file_extent_inline_len(leaf, fi);
1333 extent_end = ALIGN(extent_end, root->sectorsize);
1334 } else {
1335 BUG_ON(1);
1336 }
1337out_check:
1338 if (extent_end <= start) {
1339 path->slots[0]++;
1340 goto next_slot;
1341 }
1342 if (!nocow) {
1343 if (cow_start == (u64)-1)
1344 cow_start = cur_offset;
1345 cur_offset = extent_end;
1346 if (cur_offset > end)
1347 break;
1348 path->slots[0]++;
1349 goto next_slot;
7ea394f1
YZ		 1350 }
1351
b3b4aa74 1352 btrfs_release_path(path);
80ff3856 1353 if (cow_start != (u64)-1) {
b7d5b0a8
MX		 1354 ret = __cow_file_range(trans, inode, root, locked_page,
1355 cow_start, found_key.offset - 1,
1356 page_started, nr_written, 1);
79787eaa
JM		 1357 if (ret) {
1358 btrfs_abort_transaction(trans, root, ret);
1359 goto error;
1360 }
80ff3856 1361 cow_start = (u64)-1;
7ea394f1 1362 }
80ff3856 1363
d899e052
YZ		 1364 if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1365 struct extent_map *em;
1366 struct extent_map_tree *em_tree;
1367 em_tree = &BTRFS_I(inode)->extent_tree;
172ddd60 1368 em = alloc_extent_map();
79787eaa 1369 BUG_ON(!em); /* -ENOMEM */
d899e052 1370 em->start = cur_offset;
70c8a91c 1371 em->orig_start = found_key.offset - extent_offset;
d899e052
YZ		 1372 em->len = num_bytes;
1373 em->block_len = num_bytes;
1374 em->block_start = disk_bytenr;
b4939680 1375 em->orig_block_len = disk_num_bytes;
d899e052 1376 em->bdev = root->fs_info->fs_devices->latest_bdev;
2ab28f32
JB		 1377 em->mod_start = em->start;
1378 em->mod_len = em->len;
d899e052 1379 set_bit(EXTENT_FLAG_PINNED, &em->flags);
b11e234d 1380 set_bit(EXTENT_FLAG_FILLING, &em->flags);
70c8a91c 1381 em->generation = -1;
d899e052 1382 while (1) {
890871be 1383 write_lock(&em_tree->lock);
d899e052 1384 ret = add_extent_mapping(em_tree, em);
70c8a91c
JB		 1385 if (!ret)
1386 list_move(&em->list,
1387 &em_tree->modified_extents);
890871be 1388 write_unlock(&em_tree->lock);
d899e052
YZ		 1389 if (ret != -EEXIST) {
1390 free_extent_map(em);
1391 break;
1392 }
1393 btrfs_drop_extent_cache(inode, em->start,
1394 em->start + em->len - 1, 0);
1395 }
1396 type = BTRFS_ORDERED_PREALLOC;
1397 } else {
1398 type = BTRFS_ORDERED_NOCOW;
1399 }
80ff3856
YZ		 1400
1401 ret = btrfs_add_ordered_extent(inode, cur_offset, disk_bytenr,
d899e052 1402 num_bytes, num_bytes, type);
79787eaa 1403 BUG_ON(ret); /* -ENOMEM */
771ed689 1404
efa56464
YZ		 1405 if (root->root_key.objectid ==
1406 BTRFS_DATA_RELOC_TREE_OBJECTID) {
1407 ret = btrfs_reloc_clone_csums(inode, cur_offset,
1408 num_bytes);
79787eaa
JM		 1409 if (ret) {
1410 btrfs_abort_transaction(trans, root, ret);
1411 goto error;
1412 }
efa56464
YZ		 1413 }
1414
d899e052 1415 extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree,
a791e35e
CM		 1416 cur_offset, cur_offset + num_bytes - 1,
1417 locked_page, EXTENT_CLEAR_UNLOCK_PAGE |
1418 EXTENT_CLEAR_UNLOCK | EXTENT_CLEAR_DELALLOC |
1419 EXTENT_SET_PRIVATE2);
80ff3856
YZ		 1420 cur_offset = extent_end;
1421 if (cur_offset > end)
1422 break;
be20aa9d 1423 }
b3b4aa74 1424 btrfs_release_path(path);
80ff3856 1425
17ca04af 1426 if (cur_offset <= end && cow_start == (u64)-1) {
80ff3856 1427 cow_start = cur_offset;
17ca04af
JB		 1428 cur_offset = end;
1429 }
1430
80ff3856 1431 if (cow_start != (u64)-1) {
b7d5b0a8
MX		 1432 ret = __cow_file_range(trans, inode, root, locked_page,
1433 cow_start, end,
1434 page_started, nr_written, 1);
79787eaa
JM		 1435 if (ret) {
1436 btrfs_abort_transaction(trans, root, ret);
1437 goto error;
1438 }
80ff3856
YZ		 1439 }
1440
79787eaa 1441error:
a698d075 1442 err = btrfs_end_transaction(trans, root);
79787eaa
JM		 1443 if (!ret)
1444 ret = err;
1445
17ca04af
JB		 1446 if (ret && cur_offset < end)
1447 extent_clear_unlock_delalloc(inode,
1448 &BTRFS_I(inode)->io_tree,
1449 cur_offset, end, locked_page,
1450 EXTENT_CLEAR_UNLOCK_PAGE |
1451 EXTENT_CLEAR_UNLOCK |
1452 EXTENT_CLEAR_DELALLOC |
1453 EXTENT_CLEAR_DIRTY |
1454 EXTENT_SET_WRITEBACK |
1455 EXTENT_END_WRITEBACK);
1456
7ea394f1 1457 btrfs_free_path(path);
79787eaa 1458 return ret;
be20aa9d
CM		 1459}
1460
d352ac68
CM		 1461/*
1462 * extent_io.c call back to do delayed allocation processing
1463 */
c8b97818 1464static int run_delalloc_range(struct inode *inode, struct page *locked_page,
771ed689
CM		 1465 u64 start, u64 end, int *page_started,
1466 unsigned long *nr_written)
be20aa9d 1467{
be20aa9d 1468 int ret;
7f366cfe 1469 struct btrfs_root *root = BTRFS_I(inode)->root;
a2135011 1470
7ddf5a42 1471 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) {
c8b97818 1472 ret = run_delalloc_nocow(inode, locked_page, start, end,
d397712b 1473 page_started, 1, nr_written);
7ddf5a42 1474 } else if (BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC) {
d899e052 1475 ret = run_delalloc_nocow(inode, locked_page, start, end,
d397712b 1476 page_started, 0, nr_written);
7ddf5a42
JB		 1477 } else if (!btrfs_test_opt(root, COMPRESS) &&
1478 !(BTRFS_I(inode)->force_compress) &&
1479 !(BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS)) {
7f366cfe
CM		 1480 ret = cow_file_range(inode, locked_page, start, end,
1481 page_started, nr_written, 1);
7ddf5a42
JB		 1482 } else {
1483 set_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
1484 &BTRFS_I(inode)->runtime_flags);
771ed689 1485 ret = cow_file_range_async(inode, locked_page, start, end,
d397712b 1486 page_started, nr_written);
7ddf5a42 1487 }
b888db2b
CM		 1488 return ret;
1489}
1490
1bf85046
JM		 1491static void btrfs_split_extent_hook(struct inode *inode,
1492 struct extent_state *orig, u64 split)
9ed74f2d 1493{
0ca1f7ce 1494 /* not delalloc, ignore it */
9ed74f2d 1495 if (!(orig->state & EXTENT_DELALLOC))
1bf85046 1496 return;
9ed74f2d 1497
9e0baf60
JB		 1498 spin_lock(&BTRFS_I(inode)->lock);
1499 BTRFS_I(inode)->outstanding_extents++;
1500 spin_unlock(&BTRFS_I(inode)->lock);
9ed74f2d
JB		 1501}
1502
1503/*
1504 * extent_io.c merge_extent_hook, used to track merged delayed allocation
1505 * extents so we can keep track of new extents that are just merged onto old
1506 * extents, such as when we are doing sequential writes, so we can properly
1507 * account for the metadata space we'll need.
1508 */
1bf85046
JM		 1509static void btrfs_merge_extent_hook(struct inode *inode,
1510 struct extent_state *new,
1511 struct extent_state *other)
9ed74f2d 1512{
9ed74f2d
JB		 1513 /* not delalloc, ignore it */
1514 if (!(other->state & EXTENT_DELALLOC))
1bf85046 1515 return;
9ed74f2d 1516
9e0baf60
JB		 1517 spin_lock(&BTRFS_I(inode)->lock);
1518 BTRFS_I(inode)->outstanding_extents--;
1519 spin_unlock(&BTRFS_I(inode)->lock);
9ed74f2d
JB		 1520}
1521
d352ac68
CM		 1522/*
1523 * extent_io.c set_bit_hook, used to track delayed allocation
1524 * bytes in this file, and to maintain the list of inodes that
1525 * have pending delalloc work to be done.
1526 */
1bf85046
JM		 1527static void btrfs_set_bit_hook(struct inode *inode,
1528 struct extent_state *state, int *bits)
291d673e 1529{
9ed74f2d 1530
75eff68e
CM		 1531 /*
1532 * set_bit and clear bit hooks normally require _irqsave/restore
27160b6b 1533 * but in this case, we are only testing for the DELALLOC
75eff68e
CM		 1534 * bit, which is only set or cleared with irqs on
1535 */
0ca1f7ce 1536 if (!(state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) {
291d673e 1537 struct btrfs_root *root = BTRFS_I(inode)->root;
0ca1f7ce 1538 u64 len = state->end + 1 - state->start;
83eea1f1 1539 bool do_list = !btrfs_is_free_space_inode(inode);
9ed74f2d 1540
9e0baf60 1541 if (*bits & EXTENT_FIRST_DELALLOC) {
0ca1f7ce 1542 *bits &= ~EXTENT_FIRST_DELALLOC;
9e0baf60
JB		 1543 } else {
1544 spin_lock(&BTRFS_I(inode)->lock);
1545 BTRFS_I(inode)->outstanding_extents++;
1546 spin_unlock(&BTRFS_I(inode)->lock);
1547 }
287a0ab9 1548
963d678b
MX		 1549 __percpu_counter_add(&root->fs_info->delalloc_bytes, len,
1550 root->fs_info->delalloc_batch);
df0af1a5 1551 spin_lock(&BTRFS_I(inode)->lock);
0ca1f7ce 1552 BTRFS_I(inode)->delalloc_bytes += len;
df0af1a5
MX		 1553 if (do_list && !test_bit(BTRFS_INODE_IN_DELALLOC_LIST,
1554 &BTRFS_I(inode)->runtime_flags)) {
1555 spin_lock(&root->fs_info->delalloc_lock);
1556 if (list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
1557 list_add_tail(&BTRFS_I(inode)->delalloc_inodes,
1558 &root->fs_info->delalloc_inodes);
1559 set_bit(BTRFS_INODE_IN_DELALLOC_LIST,
1560 &BTRFS_I(inode)->runtime_flags);
1561 }
1562 spin_unlock(&root->fs_info->delalloc_lock);
ea8c2819 1563 }
df0af1a5 1564 spin_unlock(&BTRFS_I(inode)->lock);
291d673e 1565 }
291d673e
CM		 1566}
1567
d352ac68
CM		 1568/*
1569 * extent_io.c clear_bit_hook, see set_bit_hook for why
1570 */
1bf85046
JM		 1571static void btrfs_clear_bit_hook(struct inode *inode,
1572 struct extent_state *state, int *bits)
291d673e 1573{
75eff68e
CM		 1574 /*
1575 * set_bit and clear bit hooks normally require _irqsave/restore
27160b6b 1576 * but in this case, we are only testing for the DELALLOC
75eff68e
CM		 1577 * bit, which is only set or cleared with irqs on
1578 */
0ca1f7ce 1579 if ((state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) {
291d673e 1580 struct btrfs_root *root = BTRFS_I(inode)->root;
0ca1f7ce 1581 u64 len = state->end + 1 - state->start;
83eea1f1 1582 bool do_list = !btrfs_is_free_space_inode(inode);
bcbfce8a 1583
9e0baf60 1584 if (*bits & EXTENT_FIRST_DELALLOC) {
0ca1f7ce 1585 *bits &= ~EXTENT_FIRST_DELALLOC;
9e0baf60
JB		 1586 } else if (!(*bits & EXTENT_DO_ACCOUNTING)) {
1587 spin_lock(&BTRFS_I(inode)->lock);
1588 BTRFS_I(inode)->outstanding_extents--;
1589 spin_unlock(&BTRFS_I(inode)->lock);
1590 }
0ca1f7ce
YZ		 1591
1592 if (*bits & EXTENT_DO_ACCOUNTING)
1593 btrfs_delalloc_release_metadata(inode, len);
1594
0cb59c99
JB		 1595 if (root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID
1596 && do_list)
0ca1f7ce 1597 btrfs_free_reserved_data_space(inode, len);
9ed74f2d 1598
963d678b
MX		 1599 __percpu_counter_add(&root->fs_info->delalloc_bytes, -len,
1600 root->fs_info->delalloc_batch);
df0af1a5 1601 spin_lock(&BTRFS_I(inode)->lock);
0ca1f7ce 1602 BTRFS_I(inode)->delalloc_bytes -= len;
0cb59c99 1603 if (do_list && BTRFS_I(inode)->delalloc_bytes == 0 &&
df0af1a5
MX		 1604 test_bit(BTRFS_INODE_IN_DELALLOC_LIST,
1605 &BTRFS_I(inode)->runtime_flags)) {
1606 spin_lock(&root->fs_info->delalloc_lock);
1607 if (!list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
1608 list_del_init(&BTRFS_I(inode)->delalloc_inodes);
1609 clear_bit(BTRFS_INODE_IN_DELALLOC_LIST,
1610 &BTRFS_I(inode)->runtime_flags);
1611 }
1612 spin_unlock(&root->fs_info->delalloc_lock);
ea8c2819 1613 }
df0af1a5 1614 spin_unlock(&BTRFS_I(inode)->lock);
291d673e 1615 }
291d673e
CM		 1616}
1617
d352ac68
CM		 1618/*
1619 * extent_io.c merge_bio_hook, this must check the chunk tree to make sure
1620 * we don't create bios that span stripes or chunks
1621 */
64a16701 1622int btrfs_merge_bio_hook(int rw, struct page *page, unsigned long offset,
c8b97818
CM		 1623 size_t size, struct bio *bio,
1624 unsigned long bio_flags)
239b14b3
CM		 1625{
1626 struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
a62b9401 1627 u64 logical = (u64)bio->bi_sector << 9;
239b14b3
CM		 1628 u64 length = 0;
1629 u64 map_length;
239b14b3
CM		 1630 int ret;
1631
771ed689
CM		 1632 if (bio_flags & EXTENT_BIO_COMPRESSED)
1633 return 0;
1634
f2d8d74d 1635 length = bio->bi_size;
239b14b3 1636 map_length = length;
64a16701 1637 ret = btrfs_map_block(root->fs_info, rw, logical,
f188591e 1638 &map_length, NULL, 0);
3ec706c8 1639 /* Will always return 0 with map_multi == NULL */
3444a972 1640 BUG_ON(ret < 0);
d397712b 1641 if (map_length < length + size)
239b14b3 1642 return 1;
3444a972 1643 return 0;
239b14b3
CM		 1644}
1645
d352ac68
CM		 1646/*
1647 * in order to insert checksums into the metadata in large chunks,
1648 * we wait until bio submission time. All the pages in the bio are
1649 * checksummed and sums are attached onto the ordered extent record.
1650 *
1651 * At IO completion time the cums attached on the ordered extent record
1652 * are inserted into the btree
1653 */
d397712b
CM		 1654static int __btrfs_submit_bio_start(struct inode *inode, int rw,
1655 struct bio *bio, int mirror_num,
eaf25d93
CM		 1656 unsigned long bio_flags,
1657 u64 bio_offset)
065631f6 1658{
065631f6 1659 struct btrfs_root *root = BTRFS_I(inode)->root;
065631f6 1660 int ret = 0;
e015640f 1661
d20f7043 1662 ret = btrfs_csum_one_bio(root, inode, bio, 0, 0);
79787eaa 1663 BUG_ON(ret); /* -ENOMEM */
4a69a410
CM		 1664 return 0;
1665}
e015640f 1666
4a69a410
CM		 1667/*
1668 * in order to insert checksums into the metadata in large chunks,
1669 * we wait until bio submission time. All the pages in the bio are
1670 * checksummed and sums are attached onto the ordered extent record.
1671 *
1672 * At IO completion time the cums attached on the ordered extent record
1673 * are inserted into the btree
1674 */
b2950863 1675static int __btrfs_submit_bio_done(struct inode *inode, int rw, struct bio *bio,
eaf25d93
CM		 1676 int mirror_num, unsigned long bio_flags,
1677 u64 bio_offset)
4a69a410
CM		 1678{
1679 struct btrfs_root *root = BTRFS_I(inode)->root;
61891923
SB		 1680 int ret;
1681
1682 ret = btrfs_map_bio(root, rw, bio, mirror_num, 1);
1683 if (ret)
1684 bio_endio(bio, ret);
1685 return ret;
44b8bd7e
CM		 1686}
1687
d352ac68 1688/*
cad321ad
CM		 1689 * extent_io.c submission hook. This does the right thing for csum calculation
1690 * on write, or reading the csums from the tree before a read
d352ac68 1691 */
b2950863 1692static int btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
eaf25d93
CM		 1693 int mirror_num, unsigned long bio_flags,
1694 u64 bio_offset)
44b8bd7e
CM		 1695{
1696 struct btrfs_root *root = BTRFS_I(inode)->root;
1697 int ret = 0;
19b9bdb0 1698 int skip_sum;
0417341e 1699 int metadata = 0;
b812ce28 1700 int async = !atomic_read(&BTRFS_I(inode)->sync_writers);
44b8bd7e 1701
6cbff00f 1702 skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
cad321ad 1703
83eea1f1 1704 if (btrfs_is_free_space_inode(inode))
0417341e
JM		 1705 metadata = 2;
1706
7b6d91da 1707 if (!(rw & REQ_WRITE)) {
5fd02043
JB		 1708 ret = btrfs_bio_wq_end_io(root->fs_info, bio, metadata);
1709 if (ret)
61891923 1710 goto out;
5fd02043 1711
d20f7043 1712 if (bio_flags & EXTENT_BIO_COMPRESSED) {
61891923
SB		 1713 ret = btrfs_submit_compressed_read(inode, bio,
1714 mirror_num,
1715 bio_flags);
1716 goto out;
c2db1073
TI		 1717 } else if (!skip_sum) {
1718 ret = btrfs_lookup_bio_sums(root, inode, bio, NULL);
1719 if (ret)
61891923 1720 goto out;
c2db1073 1721 }
4d1b5fb4 1722 goto mapit;
b812ce28 1723 } else if (async && !skip_sum) {
17d217fe
YZ		 1724 /* csum items have already been cloned */
1725 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
1726 goto mapit;
19b9bdb0 1727 /* we're doing a write, do the async checksumming */
61891923 1728 ret = btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info,
44b8bd7e 1729 inode, rw, bio, mirror_num,
eaf25d93
CM		 1730 bio_flags, bio_offset,
1731 __btrfs_submit_bio_start,
4a69a410 1732 __btrfs_submit_bio_done);
61891923 1733 goto out;
b812ce28
JB		 1734 } else if (!skip_sum) {
1735 ret = btrfs_csum_one_bio(root, inode, bio, 0, 0);
1736 if (ret)
1737 goto out;
19b9bdb0
CM		 1738 }
1739
0b86a832 1740mapit:
61891923
SB		 1741 ret = btrfs_map_bio(root, rw, bio, mirror_num, 0);
1742
1743out:
1744 if (ret < 0)
1745 bio_endio(bio, ret);
1746 return ret;
065631f6 1747}
6885f308 1748
d352ac68
CM		 1749/*
1750 * given a list of ordered sums record them in the inode. This happens
1751 * at IO completion time based on sums calculated at bio submission time.
1752 */
ba1da2f4 1753static noinline int add_pending_csums(struct btrfs_trans_handle *trans,
e6dcd2dc
CM		 1754 struct inode *inode, u64 file_offset,
1755 struct list_head *list)
1756{
e6dcd2dc
CM		 1757 struct btrfs_ordered_sum *sum;
1758
c6e30871 1759 list_for_each_entry(sum, list, list) {
39847c4d 1760 trans->adding_csums = 1;
d20f7043
CM		 1761 btrfs_csum_file_blocks(trans,
1762 BTRFS_I(inode)->root->fs_info->csum_root, sum);
39847c4d 1763 trans->adding_csums = 0;
e6dcd2dc
CM		 1764 }
1765 return 0;
1766}
1767
2ac55d41
JB		 1768int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end,
1769 struct extent_state **cached_state)
ea8c2819 1770{
6c1500f2 1771 WARN_ON((end & (PAGE_CACHE_SIZE - 1)) == 0);
ea8c2819 1772 return set_extent_delalloc(&BTRFS_I(inode)->io_tree, start, end,
2ac55d41 1773 cached_state, GFP_NOFS);
ea8c2819
CM		 1774}
1775
d352ac68 1776/* see btrfs_writepage_start_hook for details on why this is required */
247e743c
CM		 1777struct btrfs_writepage_fixup {
1778 struct page *page;
1779 struct btrfs_work work;
1780};
1781
b2950863 1782static void btrfs_writepage_fixup_worker(struct btrfs_work *work)
247e743c
CM		 1783{
1784 struct btrfs_writepage_fixup *fixup;
1785 struct btrfs_ordered_extent *ordered;
2ac55d41 1786 struct extent_state *cached_state = NULL;
247e743c
CM		 1787 struct page *page;
1788 struct inode *inode;
1789 u64 page_start;
1790 u64 page_end;
87826df0 1791 int ret;
247e743c
CM		 1792
1793 fixup = container_of(work, struct btrfs_writepage_fixup, work);
1794 page = fixup->page;
4a096752 1795again:
247e743c
CM		 1796 lock_page(page);
1797 if (!page->mapping || !PageDirty(page) || !PageChecked(page)) {
1798 ClearPageChecked(page);
1799 goto out_page;
1800 }
1801
1802 inode = page->mapping->host;
1803 page_start = page_offset(page);
1804 page_end = page_offset(page) + PAGE_CACHE_SIZE - 1;
1805
2ac55d41 1806 lock_extent_bits(&BTRFS_I(inode)->io_tree, page_start, page_end, 0,
d0082371 1807 &cached_state);
4a096752
CM		 1808
1809 /* already ordered? We're done */
8b62b72b 1810 if (PagePrivate2(page))
247e743c 1811 goto out;
4a096752
CM		 1812
1813 ordered = btrfs_lookup_ordered_extent(inode, page_start);
1814 if (ordered) {
2ac55d41
JB		 1815 unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start,
1816 page_end, &cached_state, GFP_NOFS);
4a096752
CM		 1817 unlock_page(page);
1818 btrfs_start_ordered_extent(inode, ordered, 1);
87826df0 1819 btrfs_put_ordered_extent(ordered);
4a096752
CM		 1820 goto again;
1821 }
247e743c 1822
87826df0
JM		 1823 ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
1824 if (ret) {
1825 mapping_set_error(page->mapping, ret);
1826 end_extent_writepage(page, ret, page_start, page_end);
1827 ClearPageChecked(page);
1828 goto out;
1829 }
1830
2ac55d41 1831 btrfs_set_extent_delalloc(inode, page_start, page_end, &cached_state);
247e743c 1832 ClearPageChecked(page);
87826df0 1833 set_page_dirty(page);
247e743c 1834out:
2ac55d41
JB		 1835 unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, page_end,
1836 &cached_state, GFP_NOFS);
247e743c
CM		 1837out_page:
1838 unlock_page(page);
1839 page_cache_release(page);
b897abec 1840 kfree(fixup);
247e743c
CM		 1841}
1842
1843/*
1844 * There are a few paths in the higher layers of the kernel that directly
1845 * set the page dirty bit without asking the filesystem if it is a
1846 * good idea. This causes problems because we want to make sure COW
1847 * properly happens and the data=ordered rules are followed.
1848 *
c8b97818 1849 * In our case any range that doesn't have the ORDERED bit set
247e743c
CM		 1850 * hasn't been properly setup for IO. We kick off an async process
1851 * to fix it up. The async helper will wait for ordered extents, set
1852 * the delalloc bit and make it safe to write the page.
1853 */
b2950863 1854static int btrfs_writepage_start_hook(struct page *page, u64 start, u64 end)
247e743c
CM		 1855{
1856 struct inode *inode = page->mapping->host;
1857 struct btrfs_writepage_fixup *fixup;
1858 struct btrfs_root *root = BTRFS_I(inode)->root;
247e743c 1859
8b62b72b
CM		 1860 /* this page is properly in the ordered list */
1861 if (TestClearPagePrivate2(page))
247e743c
CM		 1862 return 0;
1863
1864 if (PageChecked(page))
1865 return -EAGAIN;
1866
1867 fixup = kzalloc(sizeof(*fixup), GFP_NOFS);
1868 if (!fixup)
1869 return -EAGAIN;
f421950f 1870
247e743c
CM		 1871 SetPageChecked(page);
1872 page_cache_get(page);
1873 fixup->work.func = btrfs_writepage_fixup_worker;
1874 fixup->page = page;
1875 btrfs_queue_worker(&root->fs_info->fixup_workers, &fixup->work);
87826df0 1876 return -EBUSY;
247e743c
CM		 1877}
1878
d899e052
YZ		 1879static int insert_reserved_file_extent(struct btrfs_trans_handle *trans,
1880 struct inode *inode, u64 file_pos,
1881 u64 disk_bytenr, u64 disk_num_bytes,
1882 u64 num_bytes, u64 ram_bytes,
1883 u8 compression, u8 encryption,
1884 u16 other_encoding, int extent_type)
1885{
1886 struct btrfs_root *root = BTRFS_I(inode)->root;
1887 struct btrfs_file_extent_item *fi;
1888 struct btrfs_path *path;
1889 struct extent_buffer *leaf;
1890 struct btrfs_key ins;
d899e052
YZ		 1891 int ret;
1892
1893 path = btrfs_alloc_path();
d8926bb3
MF		 1894 if (!path)
1895 return -ENOMEM;
d899e052 1896
b9473439 1897 path->leave_spinning = 1;
a1ed835e
CM		 1898
1899 /*
1900 * we may be replacing one extent in the tree with another.
1901 * The new extent is pinned in the extent map, and we don't want
1902 * to drop it from the cache until it is completely in the btree.
1903 *
1904 * So, tell btrfs_drop_extents to leave this extent in the cache.
1905 * the caller is expected to unpin it and allow it to be merged
1906 * with the others.
1907 */
5dc562c5 1908 ret = btrfs_drop_extents(trans, root, inode, file_pos,
2671485d 1909 file_pos + num_bytes, 0);
79787eaa
JM		 1910 if (ret)
1911 goto out;
d899e052 1912
33345d01 1913 ins.objectid = btrfs_ino(inode);
d899e052
YZ		 1914 ins.offset = file_pos;
1915 ins.type = BTRFS_EXTENT_DATA_KEY;
1916 ret = btrfs_insert_empty_item(trans, root, path, &ins, sizeof(*fi));
79787eaa
JM		 1917 if (ret)
1918 goto out;
d899e052
YZ		 1919 leaf = path->nodes[0];
1920 fi = btrfs_item_ptr(leaf, path->slots[0],
1921 struct btrfs_file_extent_item);
1922 btrfs_set_file_extent_generation(leaf, fi, trans->transid);
1923 btrfs_set_file_extent_type(leaf, fi, extent_type);
1924 btrfs_set_file_extent_disk_bytenr(leaf, fi, disk_bytenr);
1925 btrfs_set_file_extent_disk_num_bytes(leaf, fi, disk_num_bytes);
1926 btrfs_set_file_extent_offset(leaf, fi, 0);
1927 btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes);
1928 btrfs_set_file_extent_ram_bytes(leaf, fi, ram_bytes);
1929 btrfs_set_file_extent_compression(leaf, fi, compression);
1930 btrfs_set_file_extent_encryption(leaf, fi, encryption);
1931 btrfs_set_file_extent_other_encoding(leaf, fi, other_encoding);
b9473439 1932
d899e052 1933 btrfs_mark_buffer_dirty(leaf);
ce195332 1934 btrfs_release_path(path);
d899e052
YZ		 1935
1936 inode_add_bytes(inode, num_bytes);
d899e052
YZ		 1937
1938 ins.objectid = disk_bytenr;
1939 ins.offset = disk_num_bytes;
1940 ins.type = BTRFS_EXTENT_ITEM_KEY;
5d4f98a2
YZ		 1941 ret = btrfs_alloc_reserved_file_extent(trans, root,
1942 root->root_key.objectid,
33345d01 1943 btrfs_ino(inode), file_pos, &ins);
79787eaa 1944out:
d899e052 1945 btrfs_free_path(path);
b9473439 1946
79787eaa 1947 return ret;
d899e052
YZ		 1948}
1949
38c227d8
LB		 1950/* snapshot-aware defrag */
1951struct sa_defrag_extent_backref {
1952 struct rb_node node;
1953 struct old_sa_defrag_extent *old;
1954 u64 root_id;
1955 u64 inum;
1956 u64 file_pos;
1957 u64 extent_offset;
1958 u64 num_bytes;
1959 u64 generation;
1960};
1961
1962struct old_sa_defrag_extent {
1963 struct list_head list;
1964 struct new_sa_defrag_extent *new;
1965
1966 u64 extent_offset;
1967 u64 bytenr;
1968 u64 offset;
1969 u64 len;
1970 int count;
1971};
1972
1973struct new_sa_defrag_extent {
1974 struct rb_root root;
1975 struct list_head head;
1976 struct btrfs_path *path;
1977 struct inode *inode;
1978 u64 file_pos;
1979 u64 len;
1980 u64 bytenr;
1981 u64 disk_len;
1982 u8 compress_type;
1983};
1984
1985static int backref_comp(struct sa_defrag_extent_backref *b1,
1986 struct sa_defrag_extent_backref *b2)
1987{
1988 if (b1->root_id < b2->root_id)
1989 return -1;
1990 else if (b1->root_id > b2->root_id)
1991 return 1;
1992
1993 if (b1->inum < b2->inum)
1994 return -1;
1995 else if (b1->inum > b2->inum)
1996 return 1;
1997
1998 if (b1->file_pos < b2->file_pos)
1999 return -1;
2000 else if (b1->file_pos > b2->file_pos)
2001 return 1;
2002
2003 /*
2004 * [------------------------------] ===> (a range of space)
2005 * |<--->| |<---->| =============> (fs/file tree A)
2006 * |<---------------------------->| ===> (fs/file tree B)
2007 *
2008 * A range of space can refer to two file extents in one tree while
2009 * refer to only one file extent in another tree.
2010 *
2011 * So we may process a disk offset more than one time(two extents in A)
2012 * and locate at the same extent(one extent in B), then insert two same
2013 * backrefs(both refer to the extent in B).
2014 */
2015 return 0;
2016}
2017
2018static void backref_insert(struct rb_root *root,
2019 struct sa_defrag_extent_backref *backref)
2020{
2021 struct rb_node **p = &root->rb_node;
2022 struct rb_node *parent = NULL;
2023 struct sa_defrag_extent_backref *entry;
2024 int ret;
2025
2026 while (*p) {
2027 parent = *p;
2028 entry = rb_entry(parent, struct sa_defrag_extent_backref, node);
2029
2030 ret = backref_comp(backref, entry);
2031 if (ret < 0)
2032 p = &(*p)->rb_left;
2033 else
2034 p = &(*p)->rb_right;
2035 }
2036
2037 rb_link_node(&backref->node, parent, p);
2038 rb_insert_color(&backref->node, root);
2039}
2040
2041/*
2042 * Note the backref might has changed, and in this case we just return 0.
2043 */
2044static noinline int record_one_backref(u64 inum, u64 offset, u64 root_id,
2045 void *ctx)
2046{
2047 struct btrfs_file_extent_item *extent;
2048 struct btrfs_fs_info *fs_info;
2049 struct old_sa_defrag_extent *old = ctx;
2050 struct new_sa_defrag_extent *new = old->new;
2051 struct btrfs_path *path = new->path;
2052 struct btrfs_key key;
2053 struct btrfs_root *root;
2054 struct sa_defrag_extent_backref *backref;
2055 struct extent_buffer *leaf;
2056 struct inode *inode = new->inode;
2057 int slot;
2058 int ret;
2059 u64 extent_offset;
2060 u64 num_bytes;
2061
2062 if (BTRFS_I(inode)->root->root_key.objectid == root_id &&
2063 inum == btrfs_ino(inode))
2064 return 0;
2065
2066 key.objectid = root_id;
2067 key.type = BTRFS_ROOT_ITEM_KEY;
2068 key.offset = (u64)-1;
2069
2070 fs_info = BTRFS_I(inode)->root->fs_info;
2071 root = btrfs_read_fs_root_no_name(fs_info, &key);
2072 if (IS_ERR(root)) {
2073 if (PTR_ERR(root) == -ENOENT)
2074 return 0;
2075 WARN_ON(1);
2076 pr_debug("inum=%llu, offset=%llu, root_id=%llu\n",
2077 inum, offset, root_id);
2078 return PTR_ERR(root);
2079 }
2080
2081 key.objectid = inum;
2082 key.type = BTRFS_EXTENT_DATA_KEY;
2083 if (offset > (u64)-1 << 32)
2084 key.offset = 0;
2085 else
2086 key.offset = offset;
2087
2088 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2089 if (ret < 0) {
2090 WARN_ON(1);
2091 return ret;
2092 }
2093
2094 while (1) {
2095 cond_resched();
2096
2097 leaf = path->nodes[0];
2098 slot = path->slots[0];
2099
2100 if (slot >= btrfs_header_nritems(leaf)) {
2101 ret = btrfs_next_leaf(root, path);
2102 if (ret < 0) {
2103 goto out;
2104 } else if (ret > 0) {
2105 ret = 0;
2106 goto out;
2107 }
2108 continue;
2109 }
2110
2111 path->slots[0]++;
2112
2113 btrfs_item_key_to_cpu(leaf, &key, slot);
2114
2115 if (key.objectid > inum)
2116 goto out;
2117
2118 if (key.objectid < inum || key.type != BTRFS_EXTENT_DATA_KEY)
2119 continue;
2120
2121 extent = btrfs_item_ptr(leaf, slot,
2122 struct btrfs_file_extent_item);
2123
2124 if (btrfs_file_extent_disk_bytenr(leaf, extent) != old->bytenr)
2125 continue;
2126
2127 extent_offset = btrfs_file_extent_offset(leaf, extent);
2128 if (key.offset - extent_offset != offset)
2129 continue;
2130
2131 num_bytes = btrfs_file_extent_num_bytes(leaf, extent);
2132 if (extent_offset >= old->extent_offset + old->offset +
2133 old->len || extent_offset + num_bytes <=
2134 old->extent_offset + old->offset)
2135 continue;
2136
2137 break;
2138 }
2139
2140 backref = kmalloc(sizeof(*backref), GFP_NOFS);
2141 if (!backref) {
2142 ret = -ENOENT;
2143 goto out;
2144 }
2145
2146 backref->root_id = root_id;
2147 backref->inum = inum;
2148 backref->file_pos = offset + extent_offset;
2149 backref->num_bytes = num_bytes;
2150 backref->extent_offset = extent_offset;
2151 backref->generation = btrfs_file_extent_generation(leaf, extent);
2152 backref->old = old;
2153 backref_insert(&new->root, backref);
2154 old->count++;
2155out:
2156 btrfs_release_path(path);
2157 WARN_ON(ret);
2158 return ret;
2159}
2160
2161static noinline bool record_extent_backrefs(struct btrfs_path *path,
2162 struct new_sa_defrag_extent *new)
2163{
2164 struct btrfs_fs_info *fs_info = BTRFS_I(new->inode)->root->fs_info;
2165 struct old_sa_defrag_extent *old, *tmp;
2166 int ret;
2167
2168 new->path = path;
2169
2170 list_for_each_entry_safe(old, tmp, &new->head, list) {
2171 ret = iterate_inodes_from_logical(old->bytenr, fs_info,
2172 path, record_one_backref,
2173 old);
2174 BUG_ON(ret < 0 && ret != -ENOENT);
2175
2176 /* no backref to be processed for this extent */
2177 if (!old->count) {
2178 list_del(&old->list);
2179 kfree(old);
2180 }
2181 }
2182
2183 if (list_empty(&new->head))
2184 return false;
2185
2186 return true;
2187}
2188
2189static int relink_is_mergable(struct extent_buffer *leaf,
2190 struct btrfs_file_extent_item *fi,
2191 u64 disk_bytenr)
2192{
2193 if (btrfs_file_extent_disk_bytenr(leaf, fi) != disk_bytenr)
2194 return 0;
2195
2196 if (btrfs_file_extent_type(leaf, fi) != BTRFS_FILE_EXTENT_REG)
2197 return 0;
2198
2199 if (btrfs_file_extent_compression(leaf, fi) ||
2200 btrfs_file_extent_encryption(leaf, fi) ||
2201 btrfs_file_extent_other_encoding(leaf, fi))
2202 return 0;
2203
2204 return 1;
2205}
2206
2207/*
2208 * Note the backref might has changed, and in this case we just return 0.
2209 */
2210static noinline int relink_extent_backref(struct btrfs_path *path,
2211 struct sa_defrag_extent_backref *prev,
2212 struct sa_defrag_extent_backref *backref)
2213{
2214 struct btrfs_file_extent_item *extent;
2215 struct btrfs_file_extent_item *item;
2216 struct btrfs_ordered_extent *ordered;
2217 struct btrfs_trans_handle *trans;
2218 struct btrfs_fs_info *fs_info;
2219 struct btrfs_root *root;
2220 struct btrfs_key key;
2221 struct extent_buffer *leaf;
2222 struct old_sa_defrag_extent *old = backref->old;
2223 struct new_sa_defrag_extent *new = old->new;
2224 struct inode *src_inode = new->inode;
2225 struct inode *inode;
2226 struct extent_state *cached = NULL;
2227 int ret = 0;
2228 u64 start;
2229 u64 len;
2230 u64 lock_start;
2231 u64 lock_end;
2232 bool merge = false;
2233 int index;
2234
2235 if (prev && prev->root_id == backref->root_id &&
2236 prev->inum == backref->inum &&
2237 prev->file_pos + prev->num_bytes == backref->file_pos)
2238 merge = true;
2239
2240 /* step 1: get root */
2241 key.objectid = backref->root_id;
2242 key.type = BTRFS_ROOT_ITEM_KEY;
2243 key.offset = (u64)-1;
2244
2245 fs_info = BTRFS_I(src_inode)->root->fs_info;
2246 index = srcu_read_lock(&fs_info->subvol_srcu);
2247
2248 root = btrfs_read_fs_root_no_name(fs_info, &key);
2249 if (IS_ERR(root)) {
2250 srcu_read_unlock(&fs_info->subvol_srcu, index);
2251 if (PTR_ERR(root) == -ENOENT)
2252 return 0;
2253 return PTR_ERR(root);
2254 }
2255 if (btrfs_root_refs(&root->root_item) == 0) {
2256 srcu_read_unlock(&fs_info->subvol_srcu, index);
2257 /* parse ENOENT to 0 */
2258 return 0;
2259 }
2260
2261 /* step 2: get inode */
2262 key.objectid = backref->inum;
2263 key.type = BTRFS_INODE_ITEM_KEY;
2264 key.offset = 0;
2265
2266 inode = btrfs_iget(fs_info->sb, &key, root, NULL);
2267 if (IS_ERR(inode)) {
2268 srcu_read_unlock(&fs_info->subvol_srcu, index);
2269 return 0;
2270 }
2271
2272 srcu_read_unlock(&fs_info->subvol_srcu, index);
2273
2274 /* step 3: relink backref */
2275 lock_start = backref->file_pos;
2276 lock_end = backref->file_pos + backref->num_bytes - 1;
2277 lock_extent_bits(&BTRFS_I(inode)->io_tree, lock_start, lock_end,
2278 0, &cached);
2279
2280 ordered = btrfs_lookup_first_ordered_extent(inode, lock_end);
2281 if (ordered) {
2282 btrfs_put_ordered_extent(ordered);
2283 goto out_unlock;
2284 }
2285
2286 trans = btrfs_join_transaction(root);
2287 if (IS_ERR(trans)) {
2288 ret = PTR_ERR(trans);
2289 goto out_unlock;
2290 }
2291
2292 key.objectid = backref->inum;
2293 key.type = BTRFS_EXTENT_DATA_KEY;
2294 key.offset = backref->file_pos;
2295
2296 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2297 if (ret < 0) {
2298 goto out_free_path;
2299 } else if (ret > 0) {
2300 ret = 0;
2301 goto out_free_path;
2302 }
2303
2304 extent = btrfs_item_ptr(path->nodes[0], path->slots[0],
2305 struct btrfs_file_extent_item);
2306
2307 if (btrfs_file_extent_generation(path->nodes[0], extent) !=
2308 backref->generation)
2309 goto out_free_path;
2310
2311 btrfs_release_path(path);
2312
2313 start = backref->file_pos;
2314 if (backref->extent_offset < old->extent_offset + old->offset)
2315 start += old->extent_offset + old->offset -
2316 backref->extent_offset;
2317
2318 len = min(backref->extent_offset + backref->num_bytes,
2319 old->extent_offset + old->offset + old->len);
2320 len -= max(backref->extent_offset, old->extent_offset + old->offset);
2321
2322 ret = btrfs_drop_extents(trans, root, inode, start,
2323 start + len, 1);
2324 if (ret)
2325 goto out_free_path;
2326again:
2327 key.objectid = btrfs_ino(inode);
2328 key.type = BTRFS_EXTENT_DATA_KEY;
2329 key.offset = start;
2330
a09a0a70 2331 path->leave_spinning = 1;
38c227d8
LB		 2332 if (merge) {
2333 struct btrfs_file_extent_item *fi;
2334 u64 extent_len;
2335 struct btrfs_key found_key;
2336
2337 ret = btrfs_search_slot(trans, root, &key, path, 1, 1);
2338 if (ret < 0)
2339 goto out_free_path;
2340
2341 path->slots[0]--;
2342 leaf = path->nodes[0];
2343 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2344
2345 fi = btrfs_item_ptr(leaf, path->slots[0],
2346 struct btrfs_file_extent_item);
2347 extent_len = btrfs_file_extent_num_bytes(leaf, fi);
2348
2349 if (relink_is_mergable(leaf, fi, new->bytenr) &&
2350 extent_len + found_key.offset == start) {
2351 btrfs_set_file_extent_num_bytes(leaf, fi,
2352 extent_len + len);
2353 btrfs_mark_buffer_dirty(leaf);
2354 inode_add_bytes(inode, len);
2355
2356 ret = 1;
2357 goto out_free_path;
2358 } else {
2359 merge = false;
2360 btrfs_release_path(path);
2361 goto again;
2362 }
2363 }
2364
2365 ret = btrfs_insert_empty_item(trans, root, path, &key,
2366 sizeof(*extent));
2367 if (ret) {
2368 btrfs_abort_transaction(trans, root, ret);
2369 goto out_free_path;
2370 }
2371
2372 leaf = path->nodes[0];
2373 item = btrfs_item_ptr(leaf, path->slots[0],
2374 struct btrfs_file_extent_item);
2375 btrfs_set_file_extent_disk_bytenr(leaf, item, new->bytenr);
2376 btrfs_set_file_extent_disk_num_bytes(leaf, item, new->disk_len);
2377 btrfs_set_file_extent_offset(leaf, item, start - new->file_pos);
2378 btrfs_set_file_extent_num_bytes(leaf, item, len);
2379 btrfs_set_file_extent_ram_bytes(leaf, item, new->len);
2380 btrfs_set_file_extent_generation(leaf, item, trans->transid);
2381 btrfs_set_file_extent_type(leaf, item, BTRFS_FILE_EXTENT_REG);
2382 btrfs_set_file_extent_compression(leaf, item, new->compress_type);
2383 btrfs_set_file_extent_encryption(leaf, item, 0);
2384 btrfs_set_file_extent_other_encoding(leaf, item, 0);
2385
2386 btrfs_mark_buffer_dirty(leaf);
2387 inode_add_bytes(inode, len);
a09a0a70 2388 btrfs_release_path(path);
38c227d8
LB		 2389
2390 ret = btrfs_inc_extent_ref(trans, root, new->bytenr,
2391 new->disk_len, 0,
2392 backref->root_id, backref->inum,
2393 new->file_pos, 0); /* start - extent_offset */
2394 if (ret) {
2395 btrfs_abort_transaction(trans, root, ret);
2396 goto out_free_path;
2397 }
2398
2399 ret = 1;
2400out_free_path:
2401 btrfs_release_path(path);
a09a0a70 2402 path->leave_spinning = 0;
38c227d8
LB		 2403 btrfs_end_transaction(trans, root);
2404out_unlock:
2405 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lock_start, lock_end,
2406 &cached, GFP_NOFS);
2407 iput(inode);
2408 return ret;
2409}
2410
2411static void relink_file_extents(struct new_sa_defrag_extent *new)
2412{
2413 struct btrfs_path *path;
2414 struct old_sa_defrag_extent *old, *tmp;
2415 struct sa_defrag_extent_backref *backref;
2416 struct sa_defrag_extent_backref *prev = NULL;
2417 struct inode *inode;
2418 struct btrfs_root *root;
2419 struct rb_node *node;
2420 int ret;
2421
2422 inode = new->inode;
2423 root = BTRFS_I(inode)->root;
2424
2425 path = btrfs_alloc_path();
2426 if (!path)
2427 return;
2428
2429 if (!record_extent_backrefs(path, new)) {
2430 btrfs_free_path(path);
2431 goto out;
2432 }
2433 btrfs_release_path(path);
2434
2435 while (1) {
2436 node = rb_first(&new->root);
2437 if (!node)
2438 break;
2439 rb_erase(node, &new->root);
2440
2441 backref = rb_entry(node, struct sa_defrag_extent_backref, node);
2442
2443 ret = relink_extent_backref(path, prev, backref);
2444 WARN_ON(ret < 0);
2445
2446 kfree(prev);
2447
2448 if (ret == 1)
2449 prev = backref;
2450 else
2451 prev = NULL;
2452 cond_resched();
2453 }
2454 kfree(prev);
2455
2456 btrfs_free_path(path);
2457
2458 list_for_each_entry_safe(old, tmp, &new->head, list) {
2459 list_del(&old->list);
2460 kfree(old);
2461 }
2462out:
2463 atomic_dec(&root->fs_info->defrag_running);
2464 wake_up(&root->fs_info->transaction_wait);
2465
2466 kfree(new);
2467}
2468
2469static struct new_sa_defrag_extent *
2470record_old_file_extents(struct inode *inode,
2471 struct btrfs_ordered_extent *ordered)
2472{
2473 struct btrfs_root *root = BTRFS_I(inode)->root;
2474 struct btrfs_path *path;
2475 struct btrfs_key key;
2476 struct old_sa_defrag_extent *old, *tmp;
2477 struct new_sa_defrag_extent *new;
2478 int ret;
2479
2480 new = kmalloc(sizeof(*new), GFP_NOFS);
2481 if (!new)
2482 return NULL;
2483
2484 new->inode = inode;
2485 new->file_pos = ordered->file_offset;
2486 new->len = ordered->len;
2487 new->bytenr = ordered->start;
2488 new->disk_len = ordered->disk_len;
2489 new->compress_type = ordered->compress_type;
2490 new->root = RB_ROOT;
2491 INIT_LIST_HEAD(&new->head);
2492
2493 path = btrfs_alloc_path();
2494 if (!path)
2495 goto out_kfree;
2496
2497 key.objectid = btrfs_ino(inode);
2498 key.type = BTRFS_EXTENT_DATA_KEY;
2499 key.offset = new->file_pos;
2500
2501 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2502 if (ret < 0)
2503 goto out_free_path;
2504 if (ret > 0 && path->slots[0] > 0)
2505 path->slots[0]--;
2506
2507 /* find out all the old extents for the file range */
2508 while (1) {
2509 struct btrfs_file_extent_item *extent;
2510 struct extent_buffer *l;
2511 int slot;
2512 u64 num_bytes;
2513 u64 offset;
2514 u64 end;
2515 u64 disk_bytenr;
2516 u64 extent_offset;
2517
2518 l = path->nodes[0];
2519 slot = path->slots[0];
2520
2521 if (slot >= btrfs_header_nritems(l)) {
2522 ret = btrfs_next_leaf(root, path);
2523 if (ret < 0)
2524 goto out_free_list;
2525 else if (ret > 0)
2526 break;
2527 continue;
2528 }
2529
2530 btrfs_item_key_to_cpu(l, &key, slot);
2531
2532 if (key.objectid != btrfs_ino(inode))
2533 break;
2534 if (key.type != BTRFS_EXTENT_DATA_KEY)
2535 break;
2536 if (key.offset >= new->file_pos + new->len)
2537 break;
2538
2539 extent = btrfs_item_ptr(l, slot, struct btrfs_file_extent_item);
2540
2541 num_bytes = btrfs_file_extent_num_bytes(l, extent);
2542 if (key.offset + num_bytes < new->file_pos)
2543 goto next;
2544
2545 disk_bytenr = btrfs_file_extent_disk_bytenr(l, extent);
2546 if (!disk_bytenr)
2547 goto next;
2548
2549 extent_offset = btrfs_file_extent_offset(l, extent);
2550
2551 old = kmalloc(sizeof(*old), GFP_NOFS);
2552 if (!old)
2553 goto out_free_list;
2554
2555 offset = max(new->file_pos, key.offset);
2556 end = min(new->file_pos + new->len, key.offset + num_bytes);
2557
2558 old->bytenr = disk_bytenr;
2559 old->extent_offset = extent_offset;
2560 old->offset = offset - key.offset;
2561 old->len = end - offset;
2562 old->new = new;
2563 old->count = 0;
2564 list_add_tail(&old->list, &new->head);
2565next:
2566 path->slots[0]++;
2567 cond_resched();
2568 }
2569
2570 btrfs_free_path(path);
2571 atomic_inc(&root->fs_info->defrag_running);
2572
2573 return new;
2574
2575out_free_list:
2576 list_for_each_entry_safe(old, tmp, &new->head, list) {
2577 list_del(&old->list);
2578 kfree(old);
2579 }
2580out_free_path:
2581 btrfs_free_path(path);
2582out_kfree:
2583 kfree(new);
2584 return NULL;
2585}
2586
5d13a98f
CM		 2587/*
2588 * helper function for btrfs_finish_ordered_io, this
2589 * just reads in some of the csum leaves to prime them into ram
2590 * before we start the transaction. It limits the amount of btree
2591 * reads required while inside the transaction.
2592 */
d352ac68
CM		 2593/* as ordered data IO finishes, this gets called so we can finish
2594 * an ordered extent if the range of bytes in the file it covers are
2595 * fully written.
2596 */
5fd02043 2597static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent)
e6dcd2dc 2598{
5fd02043 2599 struct inode *inode = ordered_extent->inode;
e6dcd2dc 2600 struct btrfs_root *root = BTRFS_I(inode)->root;
0ca1f7ce 2601 struct btrfs_trans_handle *trans = NULL;
e6dcd2dc 2602 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
2ac55d41 2603 struct extent_state *cached_state = NULL;
38c227d8 2604 struct new_sa_defrag_extent *new = NULL;
261507a0 2605 int compress_type = 0;
e6dcd2dc 2606 int ret;
82d5902d 2607 bool nolock;
e6dcd2dc 2608
83eea1f1 2609 nolock = btrfs_is_free_space_inode(inode);
0cb59c99 2610
5fd02043
JB		 2611 if (test_bit(BTRFS_ORDERED_IOERR, &ordered_extent->flags)) {
2612 ret = -EIO;
2613 goto out;
2614 }
2615
c2167754 2616 if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags)) {
79787eaa 2617 BUG_ON(!list_empty(&ordered_extent->list)); /* Logic error */
6c760c07
JB		 2618 btrfs_ordered_update_i_size(inode, 0, ordered_extent);
2619 if (nolock)
2620 trans = btrfs_join_transaction_nolock(root);
2621 else
2622 trans = btrfs_join_transaction(root);
2623 if (IS_ERR(trans)) {
2624 ret = PTR_ERR(trans);
2625 trans = NULL;
2626 goto out;
c2167754 2627 }
6c760c07
JB		 2628 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
2629 ret = btrfs_update_inode_fallback(trans, root, inode);
2630 if (ret) /* -ENOMEM or corruption */
2631 btrfs_abort_transaction(trans, root, ret);
c2167754
YZ		 2632 goto out;
2633 }
e6dcd2dc 2634
2ac55d41
JB		 2635 lock_extent_bits(io_tree, ordered_extent->file_offset,
2636 ordered_extent->file_offset + ordered_extent->len - 1,
d0082371 2637 0, &cached_state);
e6dcd2dc 2638
38c227d8
LB		 2639 ret = test_range_bit(io_tree, ordered_extent->file_offset,
2640 ordered_extent->file_offset + ordered_extent->len - 1,
2641 EXTENT_DEFRAG, 1, cached_state);
2642 if (ret) {
2643 u64 last_snapshot = btrfs_root_last_snapshot(&root->root_item);
2644 if (last_snapshot >= BTRFS_I(inode)->generation)
2645 /* the inode is shared */
2646 new = record_old_file_extents(inode, ordered_extent);
2647
2648 clear_extent_bit(io_tree, ordered_extent->file_offset,
2649 ordered_extent->file_offset + ordered_extent->len - 1,
2650 EXTENT_DEFRAG, 0, 0, &cached_state, GFP_NOFS);
2651 }
2652
0cb59c99 2653 if (nolock)
7a7eaa40 2654 trans = btrfs_join_transaction_nolock(root);
0cb59c99 2655 else
7a7eaa40 2656 trans = btrfs_join_transaction(root);
79787eaa
JM		 2657 if (IS_ERR(trans)) {
2658 ret = PTR_ERR(trans);
2659 trans = NULL;
2660 goto out_unlock;
2661 }
0ca1f7ce 2662 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
c2167754 2663
c8b97818 2664 if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered_extent->flags))
261507a0 2665 compress_type = ordered_extent->compress_type;
d899e052 2666 if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) {
261507a0 2667 BUG_ON(compress_type);
920bbbfb 2668 ret = btrfs_mark_extent_written(trans, inode,
d899e052
YZ		 2669 ordered_extent->file_offset,
2670 ordered_extent->file_offset +
2671 ordered_extent->len);
d899e052 2672 } else {
0af3d00b 2673 BUG_ON(root == root->fs_info->tree_root);
d899e052
YZ		 2674 ret = insert_reserved_file_extent(trans, inode,
2675 ordered_extent->file_offset,
2676 ordered_extent->start,
2677 ordered_extent->disk_len,
2678 ordered_extent->len,
2679 ordered_extent->len,
261507a0 2680 compress_type, 0, 0,
d899e052 2681 BTRFS_FILE_EXTENT_REG);
d899e052 2682 }
5dc562c5
JB		 2683 unpin_extent_cache(&BTRFS_I(inode)->extent_tree,
2684 ordered_extent->file_offset, ordered_extent->len,
2685 trans->transid);
79787eaa
JM		 2686 if (ret < 0) {
2687 btrfs_abort_transaction(trans, root, ret);
5fd02043 2688 goto out_unlock;
79787eaa 2689 }
2ac55d41 2690
e6dcd2dc
CM		 2691 add_pending_csums(trans, inode, ordered_extent->file_offset,
2692 &ordered_extent->list);
2693
6c760c07
JB		 2694 btrfs_ordered_update_i_size(inode, 0, ordered_extent);
2695 ret = btrfs_update_inode_fallback(trans, root, inode);
2696 if (ret) { /* -ENOMEM or corruption */
2697 btrfs_abort_transaction(trans, root, ret);
2698 goto out_unlock;
1ef30be1
JB		 2699 }
2700 ret = 0;
5fd02043
JB		 2701out_unlock:
2702 unlock_extent_cached(io_tree, ordered_extent->file_offset,
2703 ordered_extent->file_offset +
2704 ordered_extent->len - 1, &cached_state, GFP_NOFS);
c2167754 2705out:
5b0e95bf 2706 if (root != root->fs_info->tree_root)
0cb59c99 2707 btrfs_delalloc_release_metadata(inode, ordered_extent->len);
a698d075
MX		 2708 if (trans)
2709 btrfs_end_transaction(trans, root);
0cb59c99 2710
0bec9ef5 2711 if (ret) {
5fd02043
JB		 2712 clear_extent_uptodate(io_tree, ordered_extent->file_offset,
2713 ordered_extent->file_offset +
2714 ordered_extent->len - 1, NULL, GFP_NOFS);
2715
0bec9ef5
JB		 2716 /*
2717 * If the ordered extent had an IOERR or something else went
2718 * wrong we need to return the space for this ordered extent
2719 * back to the allocator.
2720 */
2721 if (!test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags) &&
2722 !test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags))
2723 btrfs_free_reserved_extent(root, ordered_extent->start,
2724 ordered_extent->disk_len);
2725 }
2726
2727
5fd02043 2728 /*
8bad3c02
LB		 2729 * This needs to be done to make sure anybody waiting knows we are done
2730 * updating everything for this ordered extent.
5fd02043
JB		 2731 */
2732 btrfs_remove_ordered_extent(inode, ordered_extent);
2733
38c227d8
LB		 2734 /* for snapshot-aware defrag */
2735 if (new)
2736 relink_file_extents(new);
2737
e6dcd2dc
CM		 2738 /* once for us */
2739 btrfs_put_ordered_extent(ordered_extent);
2740 /* once for the tree */
2741 btrfs_put_ordered_extent(ordered_extent);
2742
5fd02043
JB		 2743 return ret;
2744}
2745
2746static void finish_ordered_fn(struct btrfs_work *work)
2747{
2748 struct btrfs_ordered_extent *ordered_extent;
2749 ordered_extent = container_of(work, struct btrfs_ordered_extent, work);
2750 btrfs_finish_ordered_io(ordered_extent);
e6dcd2dc
CM		 2751}
2752
b2950863 2753static int btrfs_writepage_end_io_hook(struct page *page, u64 start, u64 end,
211f90e6
CM		 2754 struct extent_state *state, int uptodate)
2755{
5fd02043
JB		 2756 struct inode *inode = page->mapping->host;
2757 struct btrfs_root *root = BTRFS_I(inode)->root;
2758 struct btrfs_ordered_extent *ordered_extent = NULL;
2759 struct btrfs_workers *workers;
2760
1abe9b8a 2761 trace_btrfs_writepage_end_io_hook(page, start, end, uptodate);
2762
8b62b72b 2763 ClearPagePrivate2(page);
5fd02043
JB		 2764 if (!btrfs_dec_test_ordered_pending(inode, &ordered_extent, start,
2765 end - start + 1, uptodate))
2766 return 0;
2767
2768 ordered_extent->work.func = finish_ordered_fn;
2769 ordered_extent->work.flags = 0;
2770
83eea1f1 2771 if (btrfs_is_free_space_inode(inode))
5fd02043
JB		 2772 workers = &root->fs_info->endio_freespace_worker;
2773 else
2774 workers = &root->fs_info->endio_write_workers;
2775 btrfs_queue_worker(workers, &ordered_extent->work);
2776
2777 return 0;
211f90e6
CM		 2778}
2779
d352ac68
CM		 2780/*
2781 * when reads are done, we need to check csums to verify the data is correct
4a54c8c1
JS		 2782 * if there's a match, we allow the bio to finish. If not, the code in
2783 * extent_io.c will try to find good copies for us.
d352ac68 2784 */
b2950863 2785static int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end,
5cf1ab56 2786 struct extent_state *state, int mirror)
07157aac 2787{
4eee4fa4 2788 size_t offset = start - page_offset(page);
07157aac 2789 struct inode *inode = page->mapping->host;
d1310b2e 2790 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
07157aac 2791 char *kaddr;
aadfeb6e 2792 u64 private = ~(u32)0;
07157aac 2793 int ret;
ff79f819
CM		 2794 struct btrfs_root *root = BTRFS_I(inode)->root;
2795 u32 csum = ~(u32)0;
d1310b2e 2796
d20f7043
CM		 2797 if (PageChecked(page)) {
2798 ClearPageChecked(page);
2799 goto good;
2800 }
6cbff00f
CH		 2801
2802 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)
08d2f347 2803 goto good;
17d217fe
YZ		 2804
2805 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID &&
9655d298 2806 test_range_bit(io_tree, start, end, EXTENT_NODATASUM, 1, NULL)) {
17d217fe
YZ		 2807 clear_extent_bits(io_tree, start, end, EXTENT_NODATASUM,
2808 GFP_NOFS);
b6cda9bc 2809 return 0;
17d217fe 2810 }
d20f7043 2811
c2e639f0 2812 if (state && state->start == start) {
70dec807
CM		 2813 private = state->private;
2814 ret = 0;
2815 } else {
2816 ret = get_state_private(io_tree, start, &private);
2817 }
7ac687d9 2818 kaddr = kmap_atomic(page);
d397712b 2819 if (ret)
07157aac 2820 goto zeroit;
d397712b 2821
b0496686 2822 csum = btrfs_csum_data(kaddr + offset, csum, end - start + 1);
ff79f819 2823 btrfs_csum_final(csum, (char *)&csum);
d397712b 2824 if (csum != private)
07157aac 2825 goto zeroit;
d397712b 2826
7ac687d9 2827 kunmap_atomic(kaddr);
d20f7043 2828good:
07157aac
CM		 2829 return 0;
2830
2831zeroit:
945d8962 2832 printk_ratelimited(KERN_INFO "btrfs csum failed ino %llu off %llu csum %u "
33345d01
LZ		 2833 "private %llu\n",
2834 (unsigned long long)btrfs_ino(page->mapping->host),
193f284d
CM		 2835 (unsigned long long)start, csum,
2836 (unsigned long long)private);
db94535d
CM		 2837 memset(kaddr + offset, 1, end - start + 1);
2838 flush_dcache_page(page);
7ac687d9 2839 kunmap_atomic(kaddr);
3b951516
CM		 2840 if (private == 0)
2841 return 0;
7e38326f 2842 return -EIO;
07157aac 2843}
b888db2b 2844
24bbcf04
YZ		 2845struct delayed_iput {
2846 struct list_head list;
2847 struct inode *inode;
2848};
2849
79787eaa
JM		 2850/* JDM: If this is fs-wide, why can't we add a pointer to
2851 * btrfs_inode instead and avoid the allocation? */
24bbcf04
YZ		 2852void btrfs_add_delayed_iput(struct inode *inode)
2853{
2854 struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
2855 struct delayed_iput *delayed;
2856
2857 if (atomic_add_unless(&inode->i_count, -1, 1))
2858 return;
2859
2860 delayed = kmalloc(sizeof(*delayed), GFP_NOFS | __GFP_NOFAIL);
2861 delayed->inode = inode;
2862
2863 spin_lock(&fs_info->delayed_iput_lock);
2864 list_add_tail(&delayed->list, &fs_info->delayed_iputs);
2865 spin_unlock(&fs_info->delayed_iput_lock);
2866}
2867
2868void btrfs_run_delayed_iputs(struct btrfs_root *root)
2869{
2870 LIST_HEAD(list);
2871 struct btrfs_fs_info *fs_info = root->fs_info;
2872 struct delayed_iput *delayed;
2873 int empty;
2874
2875 spin_lock(&fs_info->delayed_iput_lock);
2876 empty = list_empty(&fs_info->delayed_iputs);
2877 spin_unlock(&fs_info->delayed_iput_lock);
2878 if (empty)
2879 return;
2880
24bbcf04
YZ		 2881 spin_lock(&fs_info->delayed_iput_lock);
2882 list_splice_init(&fs_info->delayed_iputs, &list);
2883 spin_unlock(&fs_info->delayed_iput_lock);
2884
2885 while (!list_empty(&list)) {
2886 delayed = list_entry(list.next, struct delayed_iput, list);
2887 list_del(&delayed->list);
2888 iput(delayed->inode);
2889 kfree(delayed);
2890 }
24bbcf04
YZ		 2891}
2892
d68fc57b 2893/*
42b2aa86 2894 * This is called in transaction commit time. If there are no orphan
d68fc57b
YZ		 2895 * files in the subvolume, it removes orphan item and frees block_rsv
2896 * structure.
2897 */
2898void btrfs_orphan_commit_root(struct btrfs_trans_handle *trans,
2899 struct btrfs_root *root)
2900{
90290e19 2901 struct btrfs_block_rsv *block_rsv;
d68fc57b
YZ		 2902 int ret;
2903
8a35d95f 2904 if (atomic_read(&root->orphan_inodes) ||
d68fc57b
YZ		 2905 root->orphan_cleanup_state != ORPHAN_CLEANUP_DONE)
2906 return;
2907
90290e19 2908 spin_lock(&root->orphan_lock);
8a35d95f 2909 if (atomic_read(&root->orphan_inodes)) {
90290e19
JB		 2910 spin_unlock(&root->orphan_lock);
2911 return;
2912 }
2913
2914 if (root->orphan_cleanup_state != ORPHAN_CLEANUP_DONE) {
2915 spin_unlock(&root->orphan_lock);
2916 return;
2917 }
2918
2919 block_rsv = root->orphan_block_rsv;
2920 root->orphan_block_rsv = NULL;
2921 spin_unlock(&root->orphan_lock);
2922
d68fc57b
YZ		 2923 if (root->orphan_item_inserted &&
2924 btrfs_root_refs(&root->root_item) > 0) {
2925 ret = btrfs_del_orphan_item(trans, root->fs_info->tree_root,
2926 root->root_key.objectid);
2927 BUG_ON(ret);
2928 root->orphan_item_inserted = 0;
2929 }
2930
90290e19
JB		 2931 if (block_rsv) {
2932 WARN_ON(block_rsv->size > 0);
2933 btrfs_free_block_rsv(root, block_rsv);
d68fc57b
YZ		 2934 }
2935}
2936
7b128766
JB		 2937/*
2938 * This creates an orphan entry for the given inode in case something goes
2939 * wrong in the middle of an unlink/truncate.
d68fc57b
YZ		 2940 *
2941 * NOTE: caller of this function should reserve 5 units of metadata for
2942 * this function.
7b128766
JB		 2943 */
2944int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct inode *inode)
2945{
2946 struct btrfs_root *root = BTRFS_I(inode)->root;
d68fc57b
YZ		 2947 struct btrfs_block_rsv *block_rsv = NULL;
2948 int reserve = 0;
2949 int insert = 0;
2950 int ret;
7b128766 2951
d68fc57b 2952 if (!root->orphan_block_rsv) {
66d8f3dd 2953 block_rsv = btrfs_alloc_block_rsv(root, BTRFS_BLOCK_RSV_TEMP);
b532402e
TI		 2954 if (!block_rsv)
2955 return -ENOMEM;
d68fc57b 2956 }
7b128766 2957
d68fc57b
YZ		 2958 spin_lock(&root->orphan_lock);
2959 if (!root->orphan_block_rsv) {
2960 root->orphan_block_rsv = block_rsv;
2961 } else if (block_rsv) {
2962 btrfs_free_block_rsv(root, block_rsv);
2963 block_rsv = NULL;
7b128766 2964 }
7b128766 2965
8a35d95f
JB		 2966 if (!test_and_set_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
2967 &BTRFS_I(inode)->runtime_flags)) {
d68fc57b
YZ		 2968#if 0
2969 /*
2970 * For proper ENOSPC handling, we should do orphan
2971 * cleanup when mounting. But this introduces backward
2972 * compatibility issue.
2973 */
2974 if (!xchg(&root->orphan_item_inserted, 1))
2975 insert = 2;
2976 else
2977 insert = 1;
2978#endif
2979 insert = 1;
321f0e70 2980 atomic_inc(&root->orphan_inodes);
7b128766
JB		 2981 }
2982
72ac3c0d
JB		 2983 if (!test_and_set_bit(BTRFS_INODE_ORPHAN_META_RESERVED,
2984 &BTRFS_I(inode)->runtime_flags))
d68fc57b 2985 reserve = 1;
d68fc57b 2986 spin_unlock(&root->orphan_lock);
7b128766 2987
d68fc57b
YZ		 2988 /* grab metadata reservation from transaction handle */
2989 if (reserve) {
2990 ret = btrfs_orphan_reserve_metadata(trans, inode);
79787eaa 2991 BUG_ON(ret); /* -ENOSPC in reservation; Logic error? JDM */
d68fc57b 2992 }
7b128766 2993
d68fc57b
YZ		 2994 /* insert an orphan item to track this unlinked/truncated file */
2995 if (insert >= 1) {
33345d01 2996 ret = btrfs_insert_orphan_item(trans, root, btrfs_ino(inode));
79787eaa 2997 if (ret && ret != -EEXIST) {
8a35d95f
JB		 2998 clear_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
2999 &BTRFS_I(inode)->runtime_flags);
79787eaa
JM		 3000 btrfs_abort_transaction(trans, root, ret);
3001 return ret;
3002 }
3003 ret = 0;
d68fc57b
YZ		 3004 }
3005
3006 /* insert an orphan item to track subvolume contains orphan files */
3007 if (insert >= 2) {
3008 ret = btrfs_insert_orphan_item(trans, root->fs_info->tree_root,
3009 root->root_key.objectid);
79787eaa
JM		 3010 if (ret && ret != -EEXIST) {
3011 btrfs_abort_transaction(trans, root, ret);
3012 return ret;
3013 }
d68fc57b
YZ		 3014 }
3015 return 0;
7b128766
JB		 3016}
3017
3018/*
3019 * We have done the truncate/delete so we can go ahead and remove the orphan
3020 * item for this particular inode.
3021 */
3022int btrfs_orphan_del(struct btrfs_trans_handle *trans, struct inode *inode)
3023{
3024 struct btrfs_root *root = BTRFS_I(inode)->root;
d68fc57b
YZ		 3025 int delete_item = 0;
3026 int release_rsv = 0;
7b128766
JB		 3027 int ret = 0;
3028
d68fc57b 3029 spin_lock(&root->orphan_lock);
8a35d95f
JB		 3030 if (test_and_clear_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
3031 &BTRFS_I(inode)->runtime_flags))
d68fc57b 3032 delete_item = 1;
7b128766 3033
72ac3c0d
JB		 3034 if (test_and_clear_bit(BTRFS_INODE_ORPHAN_META_RESERVED,
3035 &BTRFS_I(inode)->runtime_flags))
d68fc57b 3036 release_rsv = 1;
d68fc57b 3037 spin_unlock(&root->orphan_lock);
7b128766 3038
d68fc57b 3039 if (trans && delete_item) {
33345d01 3040 ret = btrfs_del_orphan_item(trans, root, btrfs_ino(inode));
79787eaa 3041 BUG_ON(ret); /* -ENOMEM or corruption (JDM: Recheck) */
d68fc57b 3042 }
7b128766 3043
8a35d95f 3044 if (release_rsv) {
d68fc57b 3045 btrfs_orphan_release_metadata(inode);
8a35d95f
JB		 3046 atomic_dec(&root->orphan_inodes);
3047 }
7b128766 3048
d68fc57b 3049 return 0;
7b128766
JB		 3050}
3051
3052/*
3053 * this cleans up any orphans that may be left on the list from the last use
3054 * of this root.
3055 */
66b4ffd1 3056int btrfs_orphan_cleanup(struct btrfs_root *root)
7b128766
JB		 3057{
3058 struct btrfs_path *path;
3059 struct extent_buffer *leaf;
7b128766
JB		 3060 struct btrfs_key key, found_key;
3061 struct btrfs_trans_handle *trans;
3062 struct inode *inode;
8f6d7f4f 3063 u64 last_objectid = 0;
7b128766
JB		 3064 int ret = 0, nr_unlink = 0, nr_truncate = 0;
3065
d68fc57b 3066 if (cmpxchg(&root->orphan_cleanup_state, 0, ORPHAN_CLEANUP_STARTED))
66b4ffd1 3067 return 0;
c71bf099
YZ		 3068
3069 path = btrfs_alloc_path();
66b4ffd1
JB		 3070 if (!path) {
3071 ret = -ENOMEM;
3072 goto out;
3073 }
7b128766
JB		 3074 path->reada = -1;
3075
3076 key.objectid = BTRFS_ORPHAN_OBJECTID;
3077 btrfs_set_key_type(&key, BTRFS_ORPHAN_ITEM_KEY);
3078 key.offset = (u64)-1;
3079
7b128766
JB		 3080 while (1) {
3081 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
66b4ffd1
JB		 3082 if (ret < 0)
3083 goto out;
7b128766
JB		 3084
3085 /*
3086 * if ret == 0 means we found what we were searching for, which
25985edc 3087 * is weird, but possible, so only screw with path if we didn't
7b128766
JB		 3088 * find the key and see if we have stuff that matches
3089 */
3090 if (ret > 0) {
66b4ffd1 3091 ret = 0;
7b128766
JB		 3092 if (path->slots[0] == 0)
3093 break;
3094 path->slots[0]--;
3095 }
3096
3097 /* pull out the item */
3098 leaf = path->nodes[0];
7b128766
JB		 3099 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
3100
3101 /* make sure the item matches what we want */
3102 if (found_key.objectid != BTRFS_ORPHAN_OBJECTID)
3103 break;
3104 if (btrfs_key_type(&found_key) != BTRFS_ORPHAN_ITEM_KEY)
3105 break;
3106
3107 /* release the path since we're done with it */
b3b4aa74 3108 btrfs_release_path(path);
7b128766
JB		 3109
3110 /*
3111 * this is where we are basically btrfs_lookup, without the
3112 * crossing root thing. we store the inode number in the
3113 * offset of the orphan item.
3114 */
8f6d7f4f
JB		 3115
3116 if (found_key.offset == last_objectid) {
3117 printk(KERN_ERR "btrfs: Error removing orphan entry, "
3118 "stopping orphan cleanup\n");
3119 ret = -EINVAL;
3120 goto out;
3121 }
3122
3123 last_objectid = found_key.offset;
3124
5d4f98a2
YZ		 3125 found_key.objectid = found_key.offset;
3126 found_key.type = BTRFS_INODE_ITEM_KEY;
3127 found_key.offset = 0;
73f73415 3128 inode = btrfs_iget(root->fs_info->sb, &found_key, root, NULL);
a8c9e576
JB		 3129 ret = PTR_RET(inode);
3130 if (ret && ret != -ESTALE)
66b4ffd1 3131 goto out;
7b128766 3132
f8e9e0b0
AJ		 3133 if (ret == -ESTALE && root == root->fs_info->tree_root) {
3134 struct btrfs_root *dead_root;
3135 struct btrfs_fs_info *fs_info = root->fs_info;
3136 int is_dead_root = 0;
3137
3138 /*
3139 * this is an orphan in the tree root. Currently these
3140 * could come from 2 sources:
3141 * a) a snapshot deletion in progress
3142 * b) a free space cache inode
3143 * We need to distinguish those two, as the snapshot
3144 * orphan must not get deleted.
3145 * find_dead_roots already ran before us, so if this
3146 * is a snapshot deletion, we should find the root
3147 * in the dead_roots list
3148 */
3149 spin_lock(&fs_info->trans_lock);
3150 list_for_each_entry(dead_root, &fs_info->dead_roots,
3151 root_list) {
3152 if (dead_root->root_key.objectid ==
3153 found_key.objectid) {
3154 is_dead_root = 1;
3155 break;
3156 }
3157 }
3158 spin_unlock(&fs_info->trans_lock);
3159 if (is_dead_root) {
3160 /* prevent this orphan from being found again */
3161 key.offset = found_key.objectid - 1;
3162 continue;
3163 }
3164 }
7b128766 3165 /*
a8c9e576
JB		 3166 * Inode is already gone but the orphan item is still there,
3167 * kill the orphan item.
7b128766 3168 */
a8c9e576
JB		 3169 if (ret == -ESTALE) {
3170 trans = btrfs_start_transaction(root, 1);
66b4ffd1
JB		 3171 if (IS_ERR(trans)) {
3172 ret = PTR_ERR(trans);
3173 goto out;
3174 }
8a35d95f
JB		 3175 printk(KERN_ERR "auto deleting %Lu\n",
3176 found_key.objectid);
a8c9e576
JB		 3177 ret = btrfs_del_orphan_item(trans, root,
3178 found_key.objectid);
79787eaa 3179 BUG_ON(ret); /* -ENOMEM or corruption (JDM: Recheck) */
5b21f2ed 3180 btrfs_end_transaction(trans, root);
7b128766
JB		 3181 continue;
3182 }
3183
a8c9e576
JB		 3184 /*
3185 * add this inode to the orphan list so btrfs_orphan_del does
3186 * the proper thing when we hit it
3187 */
8a35d95f
JB		 3188 set_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
3189 &BTRFS_I(inode)->runtime_flags);
925396ec 3190 atomic_inc(&root->orphan_inodes);
a8c9e576 3191
7b128766
JB		 3192 /* if we have links, this was a truncate, lets do that */
3193 if (inode->i_nlink) {
a41ad394
JB		 3194 if (!S_ISREG(inode->i_mode)) {
3195 WARN_ON(1);
3196 iput(inode);
3197 continue;
3198 }
7b128766 3199 nr_truncate++;
f3fe820c
JB		 3200
3201 /* 1 for the orphan item deletion. */
3202 trans = btrfs_start_transaction(root, 1);
3203 if (IS_ERR(trans)) {
3204 ret = PTR_ERR(trans);
3205 goto out;
3206 }
3207 ret = btrfs_orphan_add(trans, inode);
3208 btrfs_end_transaction(trans, root);
3209 if (ret)
3210 goto out;
3211
66b4ffd1 3212 ret = btrfs_truncate(inode);
4a7d0f68
JB		 3213 if (ret)
3214 btrfs_orphan_del(NULL, inode);
7b128766
JB		 3215 } else {
3216 nr_unlink++;
3217 }
3218
3219 /* this will do delete_inode and everything for us */
3220 iput(inode);
66b4ffd1
JB		 3221 if (ret)
3222 goto out;
7b128766 3223 }
3254c876
MX		 3224 /* release the path since we're done with it */
3225 btrfs_release_path(path);
3226
d68fc57b
YZ		 3227 root->orphan_cleanup_state = ORPHAN_CLEANUP_DONE;
3228
3229 if (root->orphan_block_rsv)
3230 btrfs_block_rsv_release(root, root->orphan_block_rsv,
3231 (u64)-1);
3232
3233 if (root->orphan_block_rsv || root->orphan_item_inserted) {
7a7eaa40 3234 trans = btrfs_join_transaction(root);
66b4ffd1
JB		 3235 if (!IS_ERR(trans))
3236 btrfs_end_transaction(trans, root);
d68fc57b 3237 }
7b128766
JB		 3238
3239 if (nr_unlink)
3240 printk(KERN_INFO "btrfs: unlinked %d orphans\n", nr_unlink);
3241 if (nr_truncate)
3242 printk(KERN_INFO "btrfs: truncated %d orphans\n", nr_truncate);
66b4ffd1
JB		 3243
3244out:
3245 if (ret)
3246 printk(KERN_CRIT "btrfs: could not do orphan cleanup %d\n", ret);
3247 btrfs_free_path(path);
3248 return ret;
7b128766
JB		 3249}
3250
46a53cca
CM		 3251/*
3252 * very simple check to peek ahead in the leaf looking for xattrs. If we
3253 * don't find any xattrs, we know there can't be any acls.
3254 *
3255 * slot is the slot the inode is in, objectid is the objectid of the inode
3256 */
3257static noinline int acls_after_inode_item(struct extent_buffer *leaf,
3258 int slot, u64 objectid)
3259{
3260 u32 nritems = btrfs_header_nritems(leaf);
3261 struct btrfs_key found_key;
3262 int scanned = 0;
3263
3264 slot++;
3265 while (slot < nritems) {
3266 btrfs_item_key_to_cpu(leaf, &found_key, slot);
3267
3268 /* we found a different objectid, there must not be acls */
3269 if (found_key.objectid != objectid)
3270 return 0;
3271
3272 /* we found an xattr, assume we've got an acl */
3273 if (found_key.type == BTRFS_XATTR_ITEM_KEY)
3274 return 1;
3275
3276 /*
3277 * we found a key greater than an xattr key, there can't
3278 * be any acls later on
3279 */
3280 if (found_key.type > BTRFS_XATTR_ITEM_KEY)
3281 return 0;
3282
3283 slot++;
3284 scanned++;
3285
3286 /*
3287 * it goes inode, inode backrefs, xattrs, extents,
3288 * so if there are a ton of hard links to an inode there can
3289 * be a lot of backrefs. Don't waste time searching too hard,
3290 * this is just an optimization
3291 */
3292 if (scanned >= 8)
3293 break;
3294 }
3295 /* we hit the end of the leaf before we found an xattr or
3296 * something larger than an xattr. We have to assume the inode
3297 * has acls
3298 */
3299 return 1;
3300}
3301
d352ac68
CM		 3302/*
3303 * read an inode from the btree into the in-memory inode
3304 */
5d4f98a2 3305static void btrfs_read_locked_inode(struct inode *inode)
39279cc3
CM		 3306{
3307 struct btrfs_path *path;
5f39d397 3308 struct extent_buffer *leaf;
39279cc3 3309 struct btrfs_inode_item *inode_item;
0b86a832 3310 struct btrfs_timespec *tspec;
39279cc3
CM		 3311 struct btrfs_root *root = BTRFS_I(inode)->root;
3312 struct btrfs_key location;
46a53cca 3313 int maybe_acls;
618e21d5 3314 u32 rdev;
39279cc3 3315 int ret;
2f7e33d4
MX		 3316 bool filled = false;
3317
3318 ret = btrfs_fill_inode(inode, &rdev);
3319 if (!ret)
3320 filled = true;
39279cc3
CM		 3321
3322 path = btrfs_alloc_path();
1748f843
MF		 3323 if (!path)
3324 goto make_bad;
3325
d90c7321 3326 path->leave_spinning = 1;
39279cc3 3327 memcpy(&location, &BTRFS_I(inode)->location, sizeof(location));
dc17ff8f 3328
39279cc3 3329 ret = btrfs_lookup_inode(NULL, root, path, &location, 0);
5f39d397 3330 if (ret)
39279cc3 3331 goto make_bad;
39279cc3 3332
5f39d397 3333 leaf = path->nodes[0];
2f7e33d4
MX		 3334
3335 if (filled)
3336 goto cache_acl;
3337
5f39d397
CM		 3338 inode_item = btrfs_item_ptr(leaf, path->slots[0],
3339 struct btrfs_inode_item);
5f39d397 3340 inode->i_mode = btrfs_inode_mode(leaf, inode_item);
bfe86848 3341 set_nlink(inode, btrfs_inode_nlink(leaf, inode_item));
2f2f43d3
EB		 3342 i_uid_write(inode, btrfs_inode_uid(leaf, inode_item));
3343 i_gid_write(inode, btrfs_inode_gid(leaf, inode_item));
dbe674a9 3344 btrfs_i_size_write(inode, btrfs_inode_size(leaf, inode_item));
5f39d397
CM		 3345
3346 tspec = btrfs_inode_atime(inode_item);
3347 inode->i_atime.tv_sec = btrfs_timespec_sec(leaf, tspec);
3348 inode->i_atime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
3349
3350 tspec = btrfs_inode_mtime(inode_item);
3351 inode->i_mtime.tv_sec = btrfs_timespec_sec(leaf, tspec);
3352 inode->i_mtime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
3353
3354 tspec = btrfs_inode_ctime(inode_item);
3355 inode->i_ctime.tv_sec = btrfs_timespec_sec(leaf, tspec);
3356 inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
3357
a76a3cd4 3358 inode_set_bytes(inode, btrfs_inode_nbytes(leaf, inode_item));
e02119d5 3359 BTRFS_I(inode)->generation = btrfs_inode_generation(leaf, inode_item);
5dc562c5
JB		 3360 BTRFS_I(inode)->last_trans = btrfs_inode_transid(leaf, inode_item);
3361
3362 /*
3363 * If we were modified in the current generation and evicted from memory
3364 * and then re-read we need to do a full sync since we don't have any
3365 * idea about which extents were modified before we were evicted from
3366 * cache.
3367 */
3368 if (BTRFS_I(inode)->last_trans == root->fs_info->generation)
3369 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3370 &BTRFS_I(inode)->runtime_flags);
3371
0c4d2d95 3372 inode->i_version = btrfs_inode_sequence(leaf, inode_item);
e02119d5 3373 inode->i_generation = BTRFS_I(inode)->generation;
618e21d5 3374 inode->i_rdev = 0;
5f39d397
CM		 3375 rdev = btrfs_inode_rdev(leaf, inode_item);
3376
aec7477b 3377 BTRFS_I(inode)->index_cnt = (u64)-1;
d2fb3437 3378 BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item);
2f7e33d4 3379cache_acl:
46a53cca
CM		 3380 /*
3381 * try to precache a NULL acl entry for files that don't have
3382 * any xattrs or acls
3383 */
33345d01
LZ		 3384 maybe_acls = acls_after_inode_item(leaf, path->slots[0],
3385 btrfs_ino(inode));
72c04902
AV		 3386 if (!maybe_acls)
3387 cache_no_acl(inode);
46a53cca 3388
39279cc3 3389 btrfs_free_path(path);
39279cc3 3390
39279cc3 3391 switch (inode->i_mode & S_IFMT) {
39279cc3
CM		 3392 case S_IFREG:
3393 inode->i_mapping->a_ops = &btrfs_aops;
04160088 3394 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
d1310b2e 3395 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
39279cc3
CM		 3396 inode->i_fop = &btrfs_file_operations;
3397 inode->i_op = &btrfs_file_inode_operations;
3398 break;
3399 case S_IFDIR:
3400 inode->i_fop = &btrfs_dir_file_operations;
3401 if (root == root->fs_info->tree_root)
3402 inode->i_op = &btrfs_dir_ro_inode_operations;
3403 else
3404 inode->i_op = &btrfs_dir_inode_operations;
3405 break;
3406 case S_IFLNK:
3407 inode->i_op = &btrfs_symlink_inode_operations;
3408 inode->i_mapping->a_ops = &btrfs_symlink_aops;
04160088 3409 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
39279cc3 3410 break;
618e21d5 3411 default:
0279b4cd 3412 inode->i_op = &btrfs_special_inode_operations;
618e21d5
JB		 3413 init_special_inode(inode, inode->i_mode, rdev);
3414 break;
39279cc3 3415 }
6cbff00f
CH		 3416
3417 btrfs_update_iflags(inode);
39279cc3
CM		 3418 return;
3419
3420make_bad:
39279cc3 3421 btrfs_free_path(path);
39279cc3
CM		 3422 make_bad_inode(inode);
3423}
3424
d352ac68
CM		 3425/*
3426 * given a leaf and an inode, copy the inode fields into the leaf
3427 */
e02119d5
CM		 3428static void fill_inode_item(struct btrfs_trans_handle *trans,
3429 struct extent_buffer *leaf,
5f39d397 3430 struct btrfs_inode_item *item,
39279cc3
CM		 3431 struct inode *inode)
3432{
51fab693
LB		 3433 struct btrfs_map_token token;
3434
3435 btrfs_init_map_token(&token);
5f39d397 3436
51fab693
LB		 3437 btrfs_set_token_inode_uid(leaf, item, i_uid_read(inode), &token);
3438 btrfs_set_token_inode_gid(leaf, item, i_gid_read(inode), &token);
3439 btrfs_set_token_inode_size(leaf, item, BTRFS_I(inode)->disk_i_size,
3440 &token);
3441 btrfs_set_token_inode_mode(leaf, item, inode->i_mode, &token);
3442 btrfs_set_token_inode_nlink(leaf, item, inode->i_nlink, &token);
5f39d397 3443
51fab693
LB		 3444 btrfs_set_token_timespec_sec(leaf, btrfs_inode_atime(item),
3445 inode->i_atime.tv_sec, &token);
3446 btrfs_set_token_timespec_nsec(leaf, btrfs_inode_atime(item),
3447 inode->i_atime.tv_nsec, &token);
5f39d397 3448
51fab693
LB		 3449 btrfs_set_token_timespec_sec(leaf, btrfs_inode_mtime(item),
3450 inode->i_mtime.tv_sec, &token);
3451 btrfs_set_token_timespec_nsec(leaf, btrfs_inode_mtime(item),
3452 inode->i_mtime.tv_nsec, &token);
5f39d397 3453
51fab693
LB		 3454 btrfs_set_token_timespec_sec(leaf, btrfs_inode_ctime(item),
3455 inode->i_ctime.tv_sec, &token);
3456 btrfs_set_token_timespec_nsec(leaf, btrfs_inode_ctime(item),
3457 inode->i_ctime.tv_nsec, &token);
5f39d397 3458
51fab693
LB		 3459 btrfs_set_token_inode_nbytes(leaf, item, inode_get_bytes(inode),
3460 &token);
3461 btrfs_set_token_inode_generation(leaf, item, BTRFS_I(inode)->generation,
3462 &token);
3463 btrfs_set_token_inode_sequence(leaf, item, inode->i_version, &token);
3464 btrfs_set_token_inode_transid(leaf, item, trans->transid, &token);
3465 btrfs_set_token_inode_rdev(leaf, item, inode->i_rdev, &token);
3466 btrfs_set_token_inode_flags(leaf, item, BTRFS_I(inode)->flags, &token);
3467 btrfs_set_token_inode_block_group(leaf, item, 0, &token);
39279cc3
CM		 3468}
3469
d352ac68
CM		 3470/*
3471 * copy everything in the in-memory inode into the btree.
3472 */
2115133f 3473static noinline int btrfs_update_inode_item(struct btrfs_trans_handle *trans,
d397712b 3474 struct btrfs_root *root, struct inode *inode)
39279cc3
CM		 3475{
3476 struct btrfs_inode_item *inode_item;
3477 struct btrfs_path *path;
5f39d397 3478 struct extent_buffer *leaf;
39279cc3
CM		 3479 int ret;
3480
3481 path = btrfs_alloc_path();
16cdcec7
MX		 3482 if (!path)
3483 return -ENOMEM;
3484
b9473439 3485 path->leave_spinning = 1;
16cdcec7
MX		 3486 ret = btrfs_lookup_inode(trans, root, path, &BTRFS_I(inode)->location,
3487 1);
39279cc3
CM		 3488 if (ret) {
3489 if (ret > 0)
3490 ret = -ENOENT;
3491 goto failed;
3492 }
3493
b4ce94de 3494 btrfs_unlock_up_safe(path, 1);
5f39d397
CM		 3495 leaf = path->nodes[0];
3496 inode_item = btrfs_item_ptr(leaf, path->slots[0],
16cdcec7 3497 struct btrfs_inode_item);
39279cc3 3498
e02119d5 3499 fill_inode_item(trans, leaf, inode_item, inode);
5f39d397 3500 btrfs_mark_buffer_dirty(leaf);
15ee9bc7 3501 btrfs_set_inode_last_trans(trans, inode);
39279cc3
CM		 3502 ret = 0;
3503failed:
39279cc3
CM		 3504 btrfs_free_path(path);
3505 return ret;
3506}
3507
2115133f
CM		 3508/*
3509 * copy everything in the in-memory inode into the btree.
3510 */
3511noinline int btrfs_update_inode(struct btrfs_trans_handle *trans,
3512 struct btrfs_root *root, struct inode *inode)
3513{
3514 int ret;
3515
3516 /*
3517 * If the inode is a free space inode, we can deadlock during commit
3518 * if we put it into the delayed code.
3519 *
3520 * The data relocation inode should also be directly updated
3521 * without delay
3522 */
83eea1f1 3523 if (!btrfs_is_free_space_inode(inode)
2115133f 3524 && root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID) {
8ea05e3a
AB		 3525 btrfs_update_root_times(trans, root);
3526
2115133f
CM		 3527 ret = btrfs_delayed_update_inode(trans, root, inode);
3528 if (!ret)
3529 btrfs_set_inode_last_trans(trans, inode);
3530 return ret;
3531 }
3532
3533 return btrfs_update_inode_item(trans, root, inode);
3534}
3535
be6aef60
JB		 3536noinline int btrfs_update_inode_fallback(struct btrfs_trans_handle *trans,
3537 struct btrfs_root *root,
3538 struct inode *inode)
2115133f
CM		 3539{
3540 int ret;
3541
3542 ret = btrfs_update_inode(trans, root, inode);
3543 if (ret == -ENOSPC)
3544 return btrfs_update_inode_item(trans, root, inode);
3545 return ret;
3546}
3547
d352ac68
CM		 3548/*
3549 * unlink helper that gets used here in inode.c and in the tree logging
3550 * recovery code. It remove a link in a directory with a given name, and
3551 * also drops the back refs in the inode to the directory
3552 */
92986796
AV		 3553static int __btrfs_unlink_inode(struct btrfs_trans_handle *trans,
3554 struct btrfs_root *root,
3555 struct inode *dir, struct inode *inode,
3556 const char *name, int name_len)
39279cc3
CM		 3557{
3558 struct btrfs_path *path;
39279cc3 3559 int ret = 0;
5f39d397 3560 struct extent_buffer *leaf;
39279cc3 3561 struct btrfs_dir_item *di;
5f39d397 3562 struct btrfs_key key;
aec7477b 3563 u64 index;
33345d01
LZ		 3564 u64 ino = btrfs_ino(inode);
3565 u64 dir_ino = btrfs_ino(dir);
39279cc3
CM		 3566
3567 path = btrfs_alloc_path();
54aa1f4d
CM		 3568 if (!path) {
3569 ret = -ENOMEM;
554233a6 3570 goto out;
54aa1f4d
CM		 3571 }
3572
b9473439 3573 path->leave_spinning = 1;
33345d01 3574 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
39279cc3
CM		 3575 name, name_len, -1);
3576 if (IS_ERR(di)) {
3577 ret = PTR_ERR(di);
3578 goto err;
3579 }
3580 if (!di) {
3581 ret = -ENOENT;
3582 goto err;
3583 }
5f39d397
CM		 3584 leaf = path->nodes[0];
3585 btrfs_dir_item_key_to_cpu(leaf, di, &key);
39279cc3 3586 ret = btrfs_delete_one_dir_name(trans, root, path, di);
54aa1f4d
CM		 3587 if (ret)
3588 goto err;
b3b4aa74 3589 btrfs_release_path(path);
39279cc3 3590
33345d01
LZ		 3591 ret = btrfs_del_inode_ref(trans, root, name, name_len, ino,
3592 dir_ino, &index);
aec7477b 3593 if (ret) {
d397712b 3594 printk(KERN_INFO "btrfs failed to delete reference to %.*s, "
33345d01
LZ		 3595 "inode %llu parent %llu\n", name_len, name,
3596 (unsigned long long)ino, (unsigned long long)dir_ino);
79787eaa 3597 btrfs_abort_transaction(trans, root, ret);
aec7477b
JB		 3598 goto err;
3599 }
3600
16cdcec7 3601 ret = btrfs_delete_delayed_dir_index(trans, root, dir, index);
79787eaa
JM		 3602 if (ret) {
3603 btrfs_abort_transaction(trans, root, ret);
39279cc3 3604 goto err;
79787eaa 3605 }
39279cc3 3606
e02119d5 3607 ret = btrfs_del_inode_ref_in_log(trans, root, name, name_len,
33345d01 3608 inode, dir_ino);
79787eaa
JM		 3609 if (ret != 0 && ret != -ENOENT) {
3610 btrfs_abort_transaction(trans, root, ret);
3611 goto err;
3612 }
e02119d5
CM		 3613
3614 ret = btrfs_del_dir_entries_in_log(trans, root, name, name_len,
3615 dir, index);
6418c961
CM		 3616 if (ret == -ENOENT)
3617 ret = 0;
39279cc3
CM		 3618err:
3619 btrfs_free_path(path);
e02119d5
CM		 3620 if (ret)
3621 goto out;
3622
3623 btrfs_i_size_write(dir, dir->i_size - name_len * 2);
0c4d2d95
JB		 3624 inode_inc_iversion(inode);
3625 inode_inc_iversion(dir);
e02119d5 3626 inode->i_ctime = dir->i_mtime = dir->i_ctime = CURRENT_TIME;
b9959295 3627 ret = btrfs_update_inode(trans, root, dir);
e02119d5 3628out:
39279cc3
CM		 3629 return ret;
3630}
3631
92986796
AV		 3632int btrfs_unlink_inode(struct btrfs_trans_handle *trans,
3633 struct btrfs_root *root,
3634 struct inode *dir, struct inode *inode,
3635 const char *name, int name_len)
3636{
3637 int ret;
3638 ret = __btrfs_unlink_inode(trans, root, dir, inode, name, name_len);
3639 if (!ret) {
3640 btrfs_drop_nlink(inode);
3641 ret = btrfs_update_inode(trans, root, inode);
3642 }
3643 return ret;
3644}
3645
3646
a22285a6
YZ		 3647/* helper to check if there is any shared block in the path */
3648static int check_path_shared(struct btrfs_root *root,
3649 struct btrfs_path *path)
39279cc3 3650{
a22285a6
YZ		 3651 struct extent_buffer *eb;
3652 int level;
0e4dcbef 3653 u64 refs = 1;
5df6a9f6 3654
a22285a6 3655 for (level = 0; level < BTRFS_MAX_LEVEL; level++) {
dedefd72
JB		 3656 int ret;
3657
a22285a6
YZ		 3658 if (!path->nodes[level])
3659 break;
3660 eb = path->nodes[level];
3661 if (!btrfs_block_can_be_shared(root, eb))
3662 continue;
3173a18f 3663 ret = btrfs_lookup_extent_info(NULL, root, eb->start, level, 1,
a22285a6
YZ		 3664 &refs, NULL);
3665 if (refs > 1)
3666 return 1;
5df6a9f6 3667 }
dedefd72 3668 return 0;
39279cc3
CM		 3669}
3670
a22285a6
YZ		 3671/*
3672 * helper to start transaction for unlink and rmdir.
3673 *
3674 * unlink and rmdir are special in btrfs, they do not always free space.
3675 * so in enospc case, we should make sure they will free space before
3676 * allowing them to use the global metadata reservation.
3677 */
3678static struct btrfs_trans_handle *__unlink_start_trans(struct inode *dir,
3679 struct dentry *dentry)
4df27c4d 3680{
39279cc3 3681 struct btrfs_trans_handle *trans;
a22285a6 3682 struct btrfs_root *root = BTRFS_I(dir)->root;
4df27c4d 3683 struct btrfs_path *path;
4df27c4d 3684 struct btrfs_dir_item *di;
7b128766 3685 struct inode *inode = dentry->d_inode;
4df27c4d 3686 u64 index;
a22285a6
YZ		 3687 int check_link = 1;
3688 int err = -ENOSPC;
4df27c4d 3689 int ret;
33345d01
LZ		 3690 u64 ino = btrfs_ino(inode);
3691 u64 dir_ino = btrfs_ino(dir);
4df27c4d 3692
e70bea5f
JB		 3693 /*
3694 * 1 for the possible orphan item
3695 * 1 for the dir item
3696 * 1 for the dir index
3697 * 1 for the inode ref
e70bea5f
JB		 3698 * 1 for the inode
3699 */
6e137ed3 3700 trans = btrfs_start_transaction(root, 5);
a22285a6
YZ		 3701 if (!IS_ERR(trans) || PTR_ERR(trans) != -ENOSPC)
3702 return trans;
4df27c4d 3703
33345d01 3704 if (ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
a22285a6 3705 return ERR_PTR(-ENOSPC);
4df27c4d 3706
a22285a6
YZ		 3707 /* check if there is someone else holds reference */
3708 if (S_ISDIR(inode->i_mode) && atomic_read(&inode->i_count) > 1)
3709 return ERR_PTR(-ENOSPC);
4df27c4d 3710
a22285a6
YZ		 3711 if (atomic_read(&inode->i_count) > 2)
3712 return ERR_PTR(-ENOSPC);
4df27c4d 3713
a22285a6
YZ		 3714 if (xchg(&root->fs_info->enospc_unlink, 1))
3715 return ERR_PTR(-ENOSPC);
3716
3717 path = btrfs_alloc_path();
3718 if (!path) {
3719 root->fs_info->enospc_unlink = 0;
3720 return ERR_PTR(-ENOMEM);
4df27c4d
YZ		 3721 }
3722
3880a1b4
JB		 3723 /* 1 for the orphan item */
3724 trans = btrfs_start_transaction(root, 1);
5df6a9f6 3725 if (IS_ERR(trans)) {
a22285a6
YZ		 3726 btrfs_free_path(path);
3727 root->fs_info->enospc_unlink = 0;
3728 return trans;
3729 }
4df27c4d 3730
a22285a6
YZ		 3731 path->skip_locking = 1;
3732 path->search_commit_root = 1;
4df27c4d 3733
a22285a6
YZ		 3734 ret = btrfs_lookup_inode(trans, root, path,
3735 &BTRFS_I(dir)->location, 0);
3736 if (ret < 0) {
3737 err = ret;
3738 goto out;
3739 }
3740 if (ret == 0) {
3741 if (check_path_shared(root, path))
3742 goto out;
3743 } else {
3744 check_link = 0;
5df6a9f6 3745 }
b3b4aa74 3746 btrfs_release_path(path);
a22285a6
YZ		 3747
3748 ret = btrfs_lookup_inode(trans, root, path,
3749 &BTRFS_I(inode)->location, 0);
3750 if (ret < 0) {
3751 err = ret;
3752 goto out;
3753 }
3754 if (ret == 0) {
3755 if (check_path_shared(root, path))
3756 goto out;
3757 } else {
3758 check_link = 0;
3759 }
b3b4aa74 3760 btrfs_release_path(path);
a22285a6
YZ		 3761
3762 if (ret == 0 && S_ISREG(inode->i_mode)) {
3763 ret = btrfs_lookup_file_extent(trans, root, path,
33345d01 3764 ino, (u64)-1, 0);
a22285a6
YZ		 3765 if (ret < 0) {
3766 err = ret;
3767 goto out;
3768 }
79787eaa 3769 BUG_ON(ret == 0); /* Corruption */
a22285a6
YZ		 3770 if (check_path_shared(root, path))
3771 goto out;
b3b4aa74 3772 btrfs_release_path(path);
a22285a6
YZ		 3773 }
3774
3775 if (!check_link) {
3776 err = 0;
3777 goto out;
3778 }
3779
33345d01 3780 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
a22285a6
YZ		 3781 dentry->d_name.name, dentry->d_name.len, 0);
3782 if (IS_ERR(di)) {
3783 err = PTR_ERR(di);
3784 goto out;
3785 }
3786 if (di) {
3787 if (check_path_shared(root, path))
3788 goto out;
3789 } else {
3790 err = 0;
3791 goto out;
3792 }
b3b4aa74 3793 btrfs_release_path(path);
a22285a6 3794
f186373f
MF		 3795 ret = btrfs_get_inode_ref_index(trans, root, path, dentry->d_name.name,
3796 dentry->d_name.len, ino, dir_ino, 0,
3797 &index);
3798 if (ret) {
3799 err = ret;
a22285a6
YZ		 3800 goto out;
3801 }
f186373f 3802
a22285a6
YZ		 3803 if (check_path_shared(root, path))
3804 goto out;
f186373f 3805
b3b4aa74 3806 btrfs_release_path(path);
a22285a6 3807
16cdcec7
MX		 3808 /*
3809 * This is a commit root search, if we can lookup inode item and other
3810 * relative items in the commit root, it means the transaction of
3811 * dir/file creation has been committed, and the dir index item that we
3812 * delay to insert has also been inserted into the commit root. So
3813 * we needn't worry about the delayed insertion of the dir index item
3814 * here.
3815 */
33345d01 3816 di = btrfs_lookup_dir_index_item(trans, root, path, dir_ino, index,
a22285a6
YZ		 3817 dentry->d_name.name, dentry->d_name.len, 0);
3818 if (IS_ERR(di)) {
3819 err = PTR_ERR(di);
3820 goto out;
3821 }
3822 BUG_ON(ret == -ENOENT);
3823 if (check_path_shared(root, path))
3824 goto out;
3825
3826 err = 0;
3827out:
3828 btrfs_free_path(path);
3880a1b4
JB		 3829 /* Migrate the orphan reservation over */
3830 if (!err)
3831 err = btrfs_block_rsv_migrate(trans->block_rsv,
3832 &root->fs_info->global_block_rsv,
5a77d76c 3833 trans->bytes_reserved);
3880a1b4 3834
a22285a6
YZ		 3835 if (err) {
3836 btrfs_end_transaction(trans, root);
3837 root->fs_info->enospc_unlink = 0;
3838 return ERR_PTR(err);
3839 }
3840
3841 trans->block_rsv = &root->fs_info->global_block_rsv;
3842 return trans;
3843}
3844
3845static void __unlink_end_trans(struct btrfs_trans_handle *trans,
3846 struct btrfs_root *root)
3847{
66d8f3dd 3848 if (trans->block_rsv->type == BTRFS_BLOCK_RSV_GLOBAL) {
5a77d76c
JB		 3849 btrfs_block_rsv_release(root, trans->block_rsv,
3850 trans->bytes_reserved);
3851 trans->block_rsv = &root->fs_info->trans_block_rsv;
a22285a6
YZ		 3852 BUG_ON(!root->fs_info->enospc_unlink);
3853 root->fs_info->enospc_unlink = 0;
3854 }
7ad85bb7 3855 btrfs_end_transaction(trans, root);
a22285a6
YZ		 3856}
3857
3858static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
3859{
3860 struct btrfs_root *root = BTRFS_I(dir)->root;
3861 struct btrfs_trans_handle *trans;
3862 struct inode *inode = dentry->d_inode;
3863 int ret;
a22285a6
YZ		 3864
3865 trans = __unlink_start_trans(dir, dentry);
3866 if (IS_ERR(trans))
3867 return PTR_ERR(trans);
5f39d397 3868
12fcfd22
CM		 3869 btrfs_record_unlink_dir(trans, dir, dentry->d_inode, 0);
3870
e02119d5
CM		 3871 ret = btrfs_unlink_inode(trans, root, dir, dentry->d_inode,
3872 dentry->d_name.name, dentry->d_name.len);
b532402e
TI		 3873 if (ret)
3874 goto out;
7b128766 3875
a22285a6 3876 if (inode->i_nlink == 0) {
7b128766 3877 ret = btrfs_orphan_add(trans, inode);
b532402e
TI		 3878 if (ret)
3879 goto out;
a22285a6 3880 }
7b128766 3881
b532402e 3882out:
a22285a6 3883 __unlink_end_trans(trans, root);
b53d3f5d 3884 btrfs_btree_balance_dirty(root);
39279cc3
CM		 3885 return ret;
3886}
3887
4df27c4d
YZ		 3888int btrfs_unlink_subvol(struct btrfs_trans_handle *trans,
3889 struct btrfs_root *root,
3890 struct inode *dir, u64 objectid,
3891 const char *name, int name_len)
3892{
3893 struct btrfs_path *path;
3894 struct extent_buffer *leaf;
3895 struct btrfs_dir_item *di;
3896 struct btrfs_key key;
3897 u64 index;
3898 int ret;
33345d01 3899 u64 dir_ino = btrfs_ino(dir);
4df27c4d
YZ		 3900
3901 path = btrfs_alloc_path();
3902 if (!path)
3903 return -ENOMEM;
3904
33345d01 3905 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
4df27c4d 3906 name, name_len, -1);
79787eaa
JM		 3907 if (IS_ERR_OR_NULL(di)) {
3908 if (!di)
3909 ret = -ENOENT;
3910 else
3911 ret = PTR_ERR(di);
3912 goto out;
3913 }
4df27c4d
YZ		 3914
3915 leaf = path->nodes[0];
3916 btrfs_dir_item_key_to_cpu(leaf, di, &key);
3917 WARN_ON(key.type != BTRFS_ROOT_ITEM_KEY || key.objectid != objectid);
3918 ret = btrfs_delete_one_dir_name(trans, root, path, di);
79787eaa
JM		 3919 if (ret) {
3920 btrfs_abort_transaction(trans, root, ret);
3921 goto out;
3922 }
b3b4aa74 3923 btrfs_release_path(path);
4df27c4d
YZ		 3924
3925 ret = btrfs_del_root_ref(trans, root->fs_info->tree_root,
3926 objectid, root->root_key.objectid,
33345d01 3927 dir_ino, &index, name, name_len);
4df27c4d 3928 if (ret < 0) {
79787eaa
JM		 3929 if (ret != -ENOENT) {
3930 btrfs_abort_transaction(trans, root, ret);
3931 goto out;
3932 }
33345d01 3933 di = btrfs_search_dir_index_item(root, path, dir_ino,
4df27c4d 3934 name, name_len);
79787eaa
JM		 3935 if (IS_ERR_OR_NULL(di)) {
3936 if (!di)
3937 ret = -ENOENT;
3938 else
3939 ret = PTR_ERR(di);
3940 btrfs_abort_transaction(trans, root, ret);
3941 goto out;
3942 }
4df27c4d
YZ		 3943
3944 leaf = path->nodes[0];
3945 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
b3b4aa74 3946 btrfs_release_path(path);
4df27c4d
YZ		 3947 index = key.offset;
3948 }
945d8962 3949 btrfs_release_path(path);
4df27c4d 3950
16cdcec7 3951 ret = btrfs_delete_delayed_dir_index(trans, root, dir, index);
79787eaa
JM		 3952 if (ret) {
3953 btrfs_abort_transaction(trans, root, ret);
3954 goto out;
3955 }
4df27c4d
YZ		 3956
3957 btrfs_i_size_write(dir, dir->i_size - name_len * 2);
0c4d2d95 3958 inode_inc_iversion(dir);
4df27c4d 3959 dir->i_mtime = dir->i_ctime = CURRENT_TIME;
5a24e84c 3960 ret = btrfs_update_inode_fallback(trans, root, dir);
79787eaa
JM		 3961 if (ret)
3962 btrfs_abort_transaction(trans, root, ret);
3963out:
71d7aed0 3964 btrfs_free_path(path);
79787eaa 3965 return ret;
4df27c4d
YZ		 3966}
3967
39279cc3
CM		 3968static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
3969{
3970 struct inode *inode = dentry->d_inode;
1832a6d5 3971 int err = 0;
39279cc3 3972 struct btrfs_root *root = BTRFS_I(dir)->root;
39279cc3 3973 struct btrfs_trans_handle *trans;
39279cc3 3974
b3ae244e 3975 if (inode->i_size > BTRFS_EMPTY_DIR_SIZE)
134d4512 3976 return -ENOTEMPTY;
b3ae244e
DS		 3977 if (btrfs_ino(inode) == BTRFS_FIRST_FREE_OBJECTID)
3978 return -EPERM;
134d4512 3979
a22285a6
YZ		 3980 trans = __unlink_start_trans(dir, dentry);
3981 if (IS_ERR(trans))
5df6a9f6 3982 return PTR_ERR(trans);
5df6a9f6 3983
33345d01 3984 if (unlikely(btrfs_ino(inode) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
4df27c4d
YZ		 3985 err = btrfs_unlink_subvol(trans, root, dir,
3986 BTRFS_I(inode)->location.objectid,
3987 dentry->d_name.name,
3988 dentry->d_name.len);
3989 goto out;
3990 }
3991
7b128766
JB		 3992 err = btrfs_orphan_add(trans, inode);
3993 if (err)
4df27c4d 3994 goto out;
7b128766 3995
39279cc3 3996 /* now the directory is empty */
e02119d5
CM		 3997 err = btrfs_unlink_inode(trans, root, dir, dentry->d_inode,
3998 dentry->d_name.name, dentry->d_name.len);
d397712b 3999 if (!err)
dbe674a9 4000 btrfs_i_size_write(inode, 0);
4df27c4d 4001out:
a22285a6 4002 __unlink_end_trans(trans, root);
b53d3f5d 4003 btrfs_btree_balance_dirty(root);
3954401f 4004
39279cc3
CM		 4005 return err;
4006}
4007
39279cc3
CM		 4008/*
4009 * this can truncate away extent items, csum items and directory items.
4010 * It starts at a high offset and removes keys until it can't find
d352ac68 4011 * any higher than new_size
39279cc3
CM		 4012 *
4013 * csum items that cross the new i_size are truncated to the new size
4014 * as well.
7b128766
JB		 4015 *
4016 * min_type is the minimum key type to truncate down to. If set to 0, this
4017 * will kill all the items on this inode, including the INODE_ITEM_KEY.
39279cc3 4018 */
8082510e
YZ		 4019int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
4020 struct btrfs_root *root,
4021 struct inode *inode,
4022 u64 new_size, u32 min_type)
39279cc3 4023{
39279cc3 4024 struct btrfs_path *path;
5f39d397 4025 struct extent_buffer *leaf;
39279cc3 4026 struct btrfs_file_extent_item *fi;
8082510e
YZ		 4027 struct btrfs_key key;
4028 struct btrfs_key found_key;
39279cc3 4029 u64 extent_start = 0;
db94535d 4030 u64 extent_num_bytes = 0;
5d4f98a2 4031 u64 extent_offset = 0;
39279cc3 4032 u64 item_end = 0;
8082510e 4033 u32 found_type = (u8)-1;
39279cc3
CM		 4034 int found_extent;
4035 int del_item;
85e21bac
CM		 4036 int pending_del_nr = 0;
4037 int pending_del_slot = 0;
179e29e4 4038 int extent_type = -1;
8082510e
YZ		 4039 int ret;
4040 int err = 0;
33345d01 4041 u64 ino = btrfs_ino(inode);
8082510e
YZ		 4042
4043 BUG_ON(new_size > 0 && min_type != BTRFS_EXTENT_DATA_KEY);
39279cc3 4044
0eb0e19c
MF		 4045 path = btrfs_alloc_path();
4046 if (!path)
4047 return -ENOMEM;
4048 path->reada = -1;
4049
5dc562c5
JB		 4050 /*
4051 * We want to drop from the next block forward in case this new size is
4052 * not block aligned since we will be keeping the last block of the
4053 * extent just the way it is.
4054 */
0af3d00b 4055 if (root->ref_cows || root == root->fs_info->tree_root)
fda2832f
QW		 4056 btrfs_drop_extent_cache(inode, ALIGN(new_size,
4057 root->sectorsize), (u64)-1, 0);
8082510e 4058
16cdcec7
MX		 4059 /*
4060 * This function is also used to drop the items in the log tree before
4061 * we relog the inode, so if root != BTRFS_I(inode)->root, it means
4062 * it is used to drop the loged items. So we shouldn't kill the delayed
4063 * items.
4064 */
4065 if (min_type == 0 && root == BTRFS_I(inode)->root)
4066 btrfs_kill_delayed_inode_items(inode);
4067
33345d01 4068 key.objectid = ino;
39279cc3 4069 key.offset = (u64)-1;
5f39d397
CM		 4070 key.type = (u8)-1;
4071
85e21bac 4072search_again:
b9473439 4073 path->leave_spinning = 1;
85e21bac 4074 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
8082510e
YZ		 4075 if (ret < 0) {
4076 err = ret;
4077 goto out;
4078 }
d397712b 4079
85e21bac 4080 if (ret > 0) {
e02119d5
CM		 4081 /* there are no items in the tree for us to truncate, we're
4082 * done
4083 */
8082510e
YZ		 4084 if (path->slots[0] == 0)
4085 goto out;
85e21bac
CM		 4086 path->slots[0]--;
4087 }
4088
d397712b 4089 while (1) {
39279cc3 4090 fi = NULL;
5f39d397
CM		 4091 leaf = path->nodes[0];
4092 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
4093 found_type = btrfs_key_type(&found_key);
39279cc3 4094
33345d01 4095 if (found_key.objectid != ino)
39279cc3 4096 break;
5f39d397 4097
85e21bac 4098 if (found_type < min_type)
39279cc3
CM		 4099 break;
4100
5f39d397 4101 item_end = found_key.offset;
39279cc3 4102 if (found_type == BTRFS_EXTENT_DATA_KEY) {
5f39d397 4103 fi = btrfs_item_ptr(leaf, path->slots[0],
39279cc3 4104 struct btrfs_file_extent_item);
179e29e4
CM		 4105 extent_type = btrfs_file_extent_type(leaf, fi);
4106 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
5f39d397 4107 item_end +=
db94535d 4108 btrfs_file_extent_num_bytes(leaf, fi);
179e29e4 4109 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
179e29e4 4110 item_end += btrfs_file_extent_inline_len(leaf,
c8b97818 4111 fi);
39279cc3 4112 }
008630c1 4113 item_end--;
39279cc3 4114 }
8082510e
YZ		 4115 if (found_type > min_type) {
4116 del_item = 1;
4117 } else {
4118 if (item_end < new_size)
b888db2b 4119 break;
8082510e
YZ		 4120 if (found_key.offset >= new_size)
4121 del_item = 1;
4122 else
4123 del_item = 0;
39279cc3 4124 }
39279cc3 4125 found_extent = 0;
39279cc3 4126 /* FIXME, shrink the extent if the ref count is only 1 */
179e29e4
CM		 4127 if (found_type != BTRFS_EXTENT_DATA_KEY)
4128 goto delete;
4129
4130 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
39279cc3 4131 u64 num_dec;
db94535d 4132 extent_start = btrfs_file_extent_disk_bytenr(leaf, fi);
f70a9a6b 4133 if (!del_item) {
db94535d
CM		 4134 u64 orig_num_bytes =
4135 btrfs_file_extent_num_bytes(leaf, fi);
fda2832f
QW		 4136 extent_num_bytes = ALIGN(new_size -
4137 found_key.offset,
4138 root->sectorsize);
db94535d
CM		 4139 btrfs_set_file_extent_num_bytes(leaf, fi,
4140 extent_num_bytes);
4141 num_dec = (orig_num_bytes -
9069218d 4142 extent_num_bytes);
e02119d5 4143 if (root->ref_cows && extent_start != 0)
a76a3cd4 4144 inode_sub_bytes(inode, num_dec);
5f39d397 4145 btrfs_mark_buffer_dirty(leaf);
39279cc3 4146 } else {
db94535d
CM		 4147 extent_num_bytes =
4148 btrfs_file_extent_disk_num_bytes(leaf,
4149 fi);
5d4f98a2
YZ		 4150 extent_offset = found_key.offset -
4151 btrfs_file_extent_offset(leaf, fi);
4152
39279cc3 4153 /* FIXME blocksize != 4096 */
9069218d 4154 num_dec = btrfs_file_extent_num_bytes(leaf, fi);
39279cc3
CM		 4155 if (extent_start != 0) {
4156 found_extent = 1;
e02119d5 4157 if (root->ref_cows)
a76a3cd4 4158 inode_sub_bytes(inode, num_dec);
e02119d5 4159 }
39279cc3 4160 }
9069218d 4161 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
c8b97818
CM		 4162 /*
4163 * we can't truncate inline items that have had
4164 * special encodings
4165 */
4166 if (!del_item &&
4167 btrfs_file_extent_compression(leaf, fi) == 0 &&
4168 btrfs_file_extent_encryption(leaf, fi) == 0 &&
4169 btrfs_file_extent_other_encoding(leaf, fi) == 0) {
e02119d5
CM		 4170 u32 size = new_size - found_key.offset;
4171
4172 if (root->ref_cows) {
a76a3cd4
YZ		 4173 inode_sub_bytes(inode, item_end + 1 -
4174 new_size);
e02119d5
CM		 4175 }
4176 size =
4177 btrfs_file_extent_calc_inline_size(size);
143bede5
JM		 4178 btrfs_truncate_item(trans, root, path,
4179 size, 1);
e02119d5 4180 } else if (root->ref_cows) {
a76a3cd4
YZ		 4181 inode_sub_bytes(inode, item_end + 1 -
4182 found_key.offset);
9069218d 4183 }
39279cc3 4184 }
179e29e4 4185delete:
39279cc3 4186 if (del_item) {
85e21bac
CM		 4187 if (!pending_del_nr) {
4188 /* no pending yet, add ourselves */
4189 pending_del_slot = path->slots[0];
4190 pending_del_nr = 1;
4191 } else if (pending_del_nr &&
4192 path->slots[0] + 1 == pending_del_slot) {
4193 /* hop on the pending chunk */
4194 pending_del_nr++;
4195 pending_del_slot = path->slots[0];
4196 } else {
d397712b 4197 BUG();
85e21bac 4198 }
39279cc3
CM		 4199 } else {
4200 break;
4201 }
0af3d00b
JB		 4202 if (found_extent && (root->ref_cows ||
4203 root == root->fs_info->tree_root)) {
b9473439 4204 btrfs_set_path_blocking(path);
39279cc3 4205 ret = btrfs_free_extent(trans, root, extent_start,
5d4f98a2
YZ		 4206 extent_num_bytes, 0,
4207 btrfs_header_owner(leaf),
66d7e7f0 4208 ino, extent_offset, 0);
39279cc3
CM		 4209 BUG_ON(ret);
4210 }
85e21bac 4211
8082510e
YZ		 4212 if (found_type == BTRFS_INODE_ITEM_KEY)
4213 break;
4214
4215 if (path->slots[0] == 0 ||
4216 path->slots[0] != pending_del_slot) {
8082510e
YZ		 4217 if (pending_del_nr) {
4218 ret = btrfs_del_items(trans, root, path,
4219 pending_del_slot,
4220 pending_del_nr);
79787eaa
JM		 4221 if (ret) {
4222 btrfs_abort_transaction(trans,
4223 root, ret);
4224 goto error;
4225 }
8082510e
YZ		 4226 pending_del_nr = 0;
4227 }
b3b4aa74 4228 btrfs_release_path(path);
85e21bac 4229 goto search_again;
8082510e
YZ		 4230 } else {
4231 path->slots[0]--;
85e21bac 4232 }
39279cc3 4233 }
8082510e 4234out:
85e21bac
CM		 4235 if (pending_del_nr) {
4236 ret = btrfs_del_items(trans, root, path, pending_del_slot,
4237 pending_del_nr);
79787eaa
JM		 4238 if (ret)
4239 btrfs_abort_transaction(trans, root, ret);
85e21bac 4240 }
79787eaa 4241error:
39279cc3 4242 btrfs_free_path(path);
8082510e 4243 return err;
39279cc3
CM		 4244}
4245
4246/*
2aaa6655
JB		 4247 * btrfs_truncate_page - read, zero a chunk and write a page
4248 * @inode - inode that we're zeroing
4249 * @from - the offset to start zeroing
4250 * @len - the length to zero, 0 to zero the entire range respective to the
4251 * offset
4252 * @front - zero up to the offset instead of from the offset on
4253 *
4254 * This will find the page for the "from" offset and cow the page and zero the
4255 * part we want to zero. This is used with truncate and hole punching.
39279cc3 4256 */
2aaa6655
JB		 4257int btrfs_truncate_page(struct inode *inode, loff_t from, loff_t len,
4258 int front)
39279cc3 4259{
2aaa6655 4260 struct address_space *mapping = inode->i_mapping;
db94535d 4261 struct btrfs_root *root = BTRFS_I(inode)->root;
e6dcd2dc
CM		 4262 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
4263 struct btrfs_ordered_extent *ordered;
2ac55d41 4264 struct extent_state *cached_state = NULL;
e6dcd2dc 4265 char *kaddr;
db94535d 4266 u32 blocksize = root->sectorsize;
39279cc3
CM		 4267 pgoff_t index = from >> PAGE_CACHE_SHIFT;
4268 unsigned offset = from & (PAGE_CACHE_SIZE-1);
4269 struct page *page;
3b16a4e3 4270 gfp_t mask = btrfs_alloc_write_mask(mapping);
39279cc3 4271 int ret = 0;
a52d9a80 4272 u64 page_start;
e6dcd2dc 4273 u64 page_end;
39279cc3 4274
2aaa6655
JB		 4275 if ((offset & (blocksize - 1)) == 0 &&
4276 (!len || ((len & (blocksize - 1)) == 0)))
39279cc3 4277 goto out;
0ca1f7ce 4278 ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
5d5e103a
JB		 4279 if (ret)
4280 goto out;
39279cc3 4281
211c17f5 4282again:
3b16a4e3 4283 page = find_or_create_page(mapping, index, mask);
5d5e103a 4284 if (!page) {
0ca1f7ce 4285 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
ac6a2b36 4286 ret = -ENOMEM;
39279cc3 4287 goto out;
5d5e103a 4288 }
e6dcd2dc
CM		 4289
4290 page_start = page_offset(page);
4291 page_end = page_start + PAGE_CACHE_SIZE - 1;
4292
39279cc3 4293 if (!PageUptodate(page)) {
9ebefb18 4294 ret = btrfs_readpage(NULL, page);
39279cc3 4295 lock_page(page);
211c17f5
CM		 4296 if (page->mapping != mapping) {
4297 unlock_page(page);
4298 page_cache_release(page);
4299 goto again;
4300 }
39279cc3
CM		 4301 if (!PageUptodate(page)) {
4302 ret = -EIO;
89642229 4303 goto out_unlock;
39279cc3
CM		 4304 }
4305 }
211c17f5 4306 wait_on_page_writeback(page);
e6dcd2dc 4307
d0082371 4308 lock_extent_bits(io_tree, page_start, page_end, 0, &cached_state);
e6dcd2dc
CM		 4309 set_page_extent_mapped(page);
4310
4311 ordered = btrfs_lookup_ordered_extent(inode, page_start);
4312 if (ordered) {
2ac55d41
JB		 4313 unlock_extent_cached(io_tree, page_start, page_end,
4314 &cached_state, GFP_NOFS);
e6dcd2dc
CM		 4315 unlock_page(page);
4316 page_cache_release(page);
eb84ae03 4317 btrfs_start_ordered_extent(inode, ordered, 1);
e6dcd2dc
CM		 4318 btrfs_put_ordered_extent(ordered);
4319 goto again;
4320 }
4321
2ac55d41 4322 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, page_end,
9e8a4a8b
LB		 4323 EXTENT_DIRTY | EXTENT_DELALLOC |
4324 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG,
2ac55d41 4325 0, 0, &cached_state, GFP_NOFS);
5d5e103a 4326
2ac55d41
JB		 4327 ret = btrfs_set_extent_delalloc(inode, page_start, page_end,
4328 &cached_state);
9ed74f2d 4329 if (ret) {
2ac55d41
JB		 4330 unlock_extent_cached(io_tree, page_start, page_end,
4331 &cached_state, GFP_NOFS);
9ed74f2d
JB		 4332 goto out_unlock;
4333 }
4334
e6dcd2dc 4335 if (offset != PAGE_CACHE_SIZE) {
2aaa6655
JB		 4336 if (!len)
4337 len = PAGE_CACHE_SIZE - offset;
e6dcd2dc 4338 kaddr = kmap(page);
2aaa6655
JB		 4339 if (front)
4340 memset(kaddr, 0, offset);
4341 else
4342 memset(kaddr + offset, 0, len);
e6dcd2dc
CM		 4343 flush_dcache_page(page);
4344 kunmap(page);
4345 }
247e743c 4346 ClearPageChecked(page);
e6dcd2dc 4347 set_page_dirty(page);
2ac55d41
JB		 4348 unlock_extent_cached(io_tree, page_start, page_end, &cached_state,
4349 GFP_NOFS);
39279cc3 4350
89642229 4351out_unlock:
5d5e103a 4352 if (ret)
0ca1f7ce 4353 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
39279cc3
CM		 4354 unlock_page(page);
4355 page_cache_release(page);
4356out:
4357 return ret;
4358}
4359
695a0d0d
JB		 4360/*
4361 * This function puts in dummy file extents for the area we're creating a hole
4362 * for. So if we are truncating this file to a larger size we need to insert
4363 * these file extents so that btrfs_get_extent will return a EXTENT_MAP_HOLE for
4364 * the range between oldsize and size
4365 */
a41ad394 4366int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size)
39279cc3 4367{
9036c102
YZ		 4368 struct btrfs_trans_handle *trans;
4369 struct btrfs_root *root = BTRFS_I(inode)->root;
4370 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
a22285a6 4371 struct extent_map *em = NULL;
2ac55d41 4372 struct extent_state *cached_state = NULL;
5dc562c5 4373 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
fda2832f
QW		 4374 u64 hole_start = ALIGN(oldsize, root->sectorsize);
4375 u64 block_end = ALIGN(size, root->sectorsize);
9036c102
YZ		 4376 u64 last_byte;
4377 u64 cur_offset;
4378 u64 hole_size;
9ed74f2d 4379 int err = 0;
39279cc3 4380
9036c102
YZ		 4381 if (size <= hole_start)
4382 return 0;
4383
9036c102
YZ		 4384 while (1) {
4385 struct btrfs_ordered_extent *ordered;
4386 btrfs_wait_ordered_range(inode, hole_start,
4387 block_end - hole_start);
2ac55d41 4388 lock_extent_bits(io_tree, hole_start, block_end - 1, 0,
d0082371 4389 &cached_state);
9036c102
YZ		 4390 ordered = btrfs_lookup_ordered_extent(inode, hole_start);
4391 if (!ordered)
4392 break;
2ac55d41
JB		 4393 unlock_extent_cached(io_tree, hole_start, block_end - 1,
4394 &cached_state, GFP_NOFS);
9036c102
YZ		 4395 btrfs_put_ordered_extent(ordered);
4396 }
39279cc3 4397
9036c102
YZ		 4398 cur_offset = hole_start;
4399 while (1) {
4400 em = btrfs_get_extent(inode, NULL, 0, cur_offset,
4401 block_end - cur_offset, 0);
79787eaa
JM		 4402 if (IS_ERR(em)) {
4403 err = PTR_ERR(em);
f2767956 4404 em = NULL;
79787eaa
JM		 4405 break;
4406 }
9036c102 4407 last_byte = min(extent_map_end(em), block_end);
fda2832f 4408 last_byte = ALIGN(last_byte , root->sectorsize);
8082510e 4409 if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) {
5dc562c5 4410 struct extent_map *hole_em;
9036c102 4411 hole_size = last_byte - cur_offset;
9ed74f2d 4412
3642320e 4413 trans = btrfs_start_transaction(root, 3);
a22285a6
YZ		 4414 if (IS_ERR(trans)) {
4415 err = PTR_ERR(trans);
9ed74f2d 4416 break;
a22285a6 4417 }
8082510e 4418
5dc562c5
JB		 4419 err = btrfs_drop_extents(trans, root, inode,
4420 cur_offset,
2671485d 4421 cur_offset + hole_size, 1);
5b397377 4422 if (err) {
79787eaa 4423 btrfs_abort_transaction(trans, root, err);
5b397377 4424 btrfs_end_transaction(trans, root);
3893e33b 4425 break;
5b397377 4426 }
8082510e 4427
9036c102 4428 err = btrfs_insert_file_extent(trans, root,
33345d01 4429 btrfs_ino(inode), cur_offset, 0,
9036c102
YZ		 4430 0, hole_size, 0, hole_size,
4431 0, 0, 0);
5b397377 4432 if (err) {
79787eaa 4433 btrfs_abort_transaction(trans, root, err);
5b397377 4434 btrfs_end_transaction(trans, root);
3893e33b 4435 break;
5b397377 4436 }
8082510e 4437
5dc562c5
JB		 4438 btrfs_drop_extent_cache(inode, cur_offset,
4439 cur_offset + hole_size - 1, 0);
4440 hole_em = alloc_extent_map();
4441 if (!hole_em) {
4442 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
4443 &BTRFS_I(inode)->runtime_flags);
4444 goto next;
4445 }
4446 hole_em->start = cur_offset;
4447 hole_em->len = hole_size;
4448 hole_em->orig_start = cur_offset;
8082510e 4449
5dc562c5
JB		 4450 hole_em->block_start = EXTENT_MAP_HOLE;
4451 hole_em->block_len = 0;
b4939680 4452 hole_em->orig_block_len = 0;
5dc562c5
JB		 4453 hole_em->bdev = root->fs_info->fs_devices->latest_bdev;
4454 hole_em->compress_type = BTRFS_COMPRESS_NONE;
4455 hole_em->generation = trans->transid;
8082510e 4456
5dc562c5
JB		 4457 while (1) {
4458 write_lock(&em_tree->lock);
4459 err = add_extent_mapping(em_tree, hole_em);
4460 if (!err)
4461 list_move(&hole_em->list,
4462 &em_tree->modified_extents);
4463 write_unlock(&em_tree->lock);
4464 if (err != -EEXIST)
4465 break;
4466 btrfs_drop_extent_cache(inode, cur_offset,
4467 cur_offset +
4468 hole_size - 1, 0);
4469 }
4470 free_extent_map(hole_em);
4471next:
3642320e 4472 btrfs_update_inode(trans, root, inode);
8082510e 4473 btrfs_end_transaction(trans, root);
9036c102
YZ		 4474 }
4475 free_extent_map(em);
a22285a6 4476 em = NULL;
9036c102 4477 cur_offset = last_byte;
8082510e 4478 if (cur_offset >= block_end)
9036c102
YZ		 4479 break;
4480 }
1832a6d5 4481
a22285a6 4482 free_extent_map(em);
2ac55d41
JB		 4483 unlock_extent_cached(io_tree, hole_start, block_end - 1, &cached_state,
4484 GFP_NOFS);
9036c102
YZ		 4485 return err;
4486}
39279cc3 4487
3972f260 4488static int btrfs_setsize(struct inode *inode, struct iattr *attr)
8082510e 4489{
f4a2f4c5
MX		 4490 struct btrfs_root *root = BTRFS_I(inode)->root;
4491 struct btrfs_trans_handle *trans;
a41ad394 4492 loff_t oldsize = i_size_read(inode);
3972f260
ES		 4493 loff_t newsize = attr->ia_size;
4494 int mask = attr->ia_valid;
8082510e
YZ		 4495 int ret;
4496
a41ad394 4497 if (newsize == oldsize)
8082510e
YZ		 4498 return 0;
4499
3972f260
ES		 4500 /*
4501 * The regular truncate() case without ATTR_CTIME and ATTR_MTIME is a
4502 * special case where we need to update the times despite not having
4503 * these flags set. For all other operations the VFS set these flags
4504 * explicitly if it wants a timestamp update.
4505 */
4506 if (newsize != oldsize && (!(mask & (ATTR_CTIME | ATTR_MTIME))))
4507 inode->i_ctime = inode->i_mtime = current_fs_time(inode->i_sb);
4508
a41ad394 4509 if (newsize > oldsize) {
a41ad394
JB		 4510 truncate_pagecache(inode, oldsize, newsize);
4511 ret = btrfs_cont_expand(inode, oldsize, newsize);
f4a2f4c5 4512 if (ret)
8082510e 4513 return ret;
8082510e 4514
f4a2f4c5
MX		 4515 trans = btrfs_start_transaction(root, 1);
4516 if (IS_ERR(trans))
4517 return PTR_ERR(trans);
4518
4519 i_size_write(inode, newsize);
4520 btrfs_ordered_update_i_size(inode, i_size_read(inode), NULL);
4521 ret = btrfs_update_inode(trans, root, inode);
7ad85bb7 4522 btrfs_end_transaction(trans, root);
a41ad394 4523 } else {
8082510e 4524
a41ad394
JB		 4525 /*
4526 * We're truncating a file that used to have good data down to
4527 * zero. Make sure it gets into the ordered flush list so that
4528 * any new writes get down to disk quickly.
4529 */
4530 if (newsize == 0)
72ac3c0d
JB		 4531 set_bit(BTRFS_INODE_ORDERED_DATA_CLOSE,
4532 &BTRFS_I(inode)->runtime_flags);
8082510e 4533
f3fe820c
JB		 4534 /*
4535 * 1 for the orphan item we're going to add
4536 * 1 for the orphan item deletion.
4537 */
4538 trans = btrfs_start_transaction(root, 2);
4539 if (IS_ERR(trans))
4540 return PTR_ERR(trans);
4541
4542 /*
4543 * We need to do this in case we fail at _any_ point during the
4544 * actual truncate. Once we do the truncate_setsize we could
4545 * invalidate pages which forces any outstanding ordered io to
4546 * be instantly completed which will give us extents that need
4547 * to be truncated. If we fail to get an orphan inode down we
4548 * could have left over extents that were never meant to live,
4549 * so we need to garuntee from this point on that everything
4550 * will be consistent.
4551 */
4552 ret = btrfs_orphan_add(trans, inode);
4553 btrfs_end_transaction(trans, root);
4554 if (ret)
4555 return ret;
4556
a41ad394
JB		 4557 /* we don't support swapfiles, so vmtruncate shouldn't fail */
4558 truncate_setsize(inode, newsize);
2e60a51e
MX		 4559
4560 /* Disable nonlocked read DIO to avoid the end less truncate */
4561 btrfs_inode_block_unlocked_dio(inode);
4562 inode_dio_wait(inode);
4563 btrfs_inode_resume_unlocked_dio(inode);
4564
a41ad394 4565 ret = btrfs_truncate(inode);
f3fe820c
JB		 4566 if (ret && inode->i_nlink)
4567 btrfs_orphan_del(NULL, inode);
8082510e
YZ		 4568 }
4569
a41ad394 4570 return ret;
8082510e
YZ		 4571}
4572
9036c102
YZ		 4573static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
4574{
4575 struct inode *inode = dentry->d_inode;
b83cc969 4576 struct btrfs_root *root = BTRFS_I(inode)->root;
9036c102 4577 int err;
39279cc3 4578
b83cc969
LZ		 4579 if (btrfs_root_readonly(root))
4580 return -EROFS;
4581
9036c102
YZ		 4582 err = inode_change_ok(inode, attr);
4583 if (err)
4584 return err;
2bf5a725 4585
5a3f23d5 4586 if (S_ISREG(inode->i_mode) && (attr->ia_valid & ATTR_SIZE)) {
3972f260 4587 err = btrfs_setsize(inode, attr);
8082510e
YZ		 4588 if (err)
4589 return err;
39279cc3 4590 }
9036c102 4591
1025774c
CH		 4592 if (attr->ia_valid) {
4593 setattr_copy(inode, attr);
0c4d2d95 4594 inode_inc_iversion(inode);
22c44fe6 4595 err = btrfs_dirty_inode(inode);
1025774c 4596
22c44fe6 4597 if (!err && attr->ia_valid & ATTR_MODE)
1025774c
CH		 4598 err = btrfs_acl_chmod(inode);
4599 }
33268eaf 4600
39279cc3
CM		 4601 return err;
4602}
61295eb8 4603
bd555975 4604void btrfs_evict_inode(struct inode *inode)
39279cc3
CM		 4605{
4606 struct btrfs_trans_handle *trans;
4607 struct btrfs_root *root = BTRFS_I(inode)->root;
726c35fa 4608 struct btrfs_block_rsv *rsv, *global_rsv;
07127184 4609 u64 min_size = btrfs_calc_trunc_metadata_size(root, 1);
39279cc3
CM		 4610 int ret;
4611
1abe9b8a 4612 trace_btrfs_inode_evict(inode);
4613
39279cc3 4614 truncate_inode_pages(&inode->i_data, 0);
0af3d00b 4615 if (inode->i_nlink && (btrfs_root_refs(&root->root_item) != 0 ||
83eea1f1 4616 btrfs_is_free_space_inode(inode)))
bd555975
AV		 4617 goto no_delete;
4618
39279cc3 4619 if (is_bad_inode(inode)) {
7b128766 4620 btrfs_orphan_del(NULL, inode);
39279cc3
CM		 4621 goto no_delete;
4622 }
bd555975 4623 /* do we really want it for ->i_nlink > 0 and zero btrfs_root_refs? */
4a096752 4624 btrfs_wait_ordered_range(inode, 0, (u64)-1);
5f39d397 4625
c71bf099 4626 if (root->fs_info->log_root_recovering) {
6bf02314 4627 BUG_ON(test_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
8a35d95f 4628 &BTRFS_I(inode)->runtime_flags));
c71bf099
YZ		 4629 goto no_delete;
4630 }
4631
76dda93c
YZ		 4632 if (inode->i_nlink > 0) {
4633 BUG_ON(btrfs_root_refs(&root->root_item) != 0);
4634 goto no_delete;
4635 }
4636
0e8c36a9
MX		 4637 ret = btrfs_commit_inode_delayed_inode(inode);
4638 if (ret) {
4639 btrfs_orphan_del(NULL, inode);
4640 goto no_delete;
4641 }
4642
66d8f3dd 4643 rsv = btrfs_alloc_block_rsv(root, BTRFS_BLOCK_RSV_TEMP);
4289a667
JB		 4644 if (!rsv) {
4645 btrfs_orphan_del(NULL, inode);
4646 goto no_delete;
4647 }
4a338542 4648 rsv->size = min_size;
ca7e70f5 4649 rsv->failfast = 1;
726c35fa 4650 global_rsv = &root->fs_info->global_block_rsv;
4289a667 4651
dbe674a9 4652 btrfs_i_size_write(inode, 0);
5f39d397 4653
4289a667 4654 /*
8407aa46
MX		 4655 * This is a bit simpler than btrfs_truncate since we've already
4656 * reserved our space for our orphan item in the unlink, so we just
4657 * need to reserve some slack space in case we add bytes and update
4658 * inode item when doing the truncate.
4289a667 4659 */
8082510e 4660 while (1) {
08e007d2
MX		 4661 ret = btrfs_block_rsv_refill(root, rsv, min_size,
4662 BTRFS_RESERVE_FLUSH_LIMIT);
726c35fa
JB		 4663
4664 /*
4665 * Try and steal from the global reserve since we will
4666 * likely not use this space anyway, we want to try as
4667 * hard as possible to get this to work.
4668 */
4669 if (ret)
4670 ret = btrfs_block_rsv_migrate(global_rsv, rsv, min_size);
d68fc57b 4671
d68fc57b 4672 if (ret) {
4289a667 4673 printk(KERN_WARNING "Could not get space for a "
482e6dc5 4674 "delete, will truncate on mount %d\n", ret);
4289a667
JB		 4675 btrfs_orphan_del(NULL, inode);
4676 btrfs_free_block_rsv(root, rsv);
4677 goto no_delete;
d68fc57b 4678 }
7b128766 4679
0e8c36a9 4680 trans = btrfs_join_transaction(root);
4289a667
JB		 4681 if (IS_ERR(trans)) {
4682 btrfs_orphan_del(NULL, inode);
4683 btrfs_free_block_rsv(root, rsv);
4684 goto no_delete;
d68fc57b 4685 }
7b128766 4686
4289a667
JB		 4687 trans->block_rsv = rsv;
4688
d68fc57b 4689 ret = btrfs_truncate_inode_items(trans, root, inode, 0, 0);
ca7e70f5 4690 if (ret != -ENOSPC)
8082510e 4691 break;
85e21bac 4692
8407aa46 4693 trans->block_rsv = &root->fs_info->trans_block_rsv;
8082510e
YZ		 4694 btrfs_end_transaction(trans, root);
4695 trans = NULL;
b53d3f5d 4696 btrfs_btree_balance_dirty(root);
8082510e 4697 }
5f39d397 4698
4289a667
JB		 4699 btrfs_free_block_rsv(root, rsv);
4700
8082510e 4701 if (ret == 0) {
4289a667 4702 trans->block_rsv = root->orphan_block_rsv;
8082510e
YZ		 4703 ret = btrfs_orphan_del(trans, inode);
4704 BUG_ON(ret);
4705 }
54aa1f4d 4706
4289a667 4707 trans->block_rsv = &root->fs_info->trans_block_rsv;
581bb050
LZ		 4708 if (!(root == root->fs_info->tree_root ||
4709 root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID))
33345d01 4710 btrfs_return_ino(root, btrfs_ino(inode));
581bb050 4711
54aa1f4d 4712 btrfs_end_transaction(trans, root);
b53d3f5d 4713 btrfs_btree_balance_dirty(root);
39279cc3 4714no_delete:
dbd5768f 4715 clear_inode(inode);
8082510e 4716 return;
39279cc3
CM		 4717}
4718
4719/*
4720 * this returns the key found in the dir entry in the location pointer.
4721 * If no dir entries were found, location->objectid is 0.
4722 */
4723static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
4724 struct btrfs_key *location)
4725{
4726 const char *name = dentry->d_name.name;
4727 int namelen = dentry->d_name.len;
4728 struct btrfs_dir_item *di;
4729 struct btrfs_path *path;
4730 struct btrfs_root *root = BTRFS_I(dir)->root;
0d9f7f3e 4731 int ret = 0;
39279cc3
CM		 4732
4733 path = btrfs_alloc_path();
d8926bb3
MF		 4734 if (!path)
4735 return -ENOMEM;
3954401f 4736
33345d01 4737 di = btrfs_lookup_dir_item(NULL, root, path, btrfs_ino(dir), name,
39279cc3 4738 namelen, 0);
0d9f7f3e
Y		 4739 if (IS_ERR(di))
4740 ret = PTR_ERR(di);
d397712b 4741
c704005d 4742 if (IS_ERR_OR_NULL(di))
3954401f 4743 goto out_err;
d397712b 4744
5f39d397 4745 btrfs_dir_item_key_to_cpu(path->nodes[0], di, location);
39279cc3 4746out:
39279cc3
CM		 4747 btrfs_free_path(path);
4748 return ret;
3954401f
CM		 4749out_err:
4750 location->objectid = 0;
4751 goto out;
39279cc3
CM		 4752}
4753
4754/*
4755 * when we hit a tree root in a directory, the btrfs part of the inode
4756 * needs to be changed to reflect the root directory of the tree root. This
4757 * is kind of like crossing a mount point.
4758 */
4759static int fixup_tree_root_location(struct btrfs_root *root,
4df27c4d
YZ		 4760 struct inode *dir,
4761 struct dentry *dentry,
4762 struct btrfs_key *location,
4763 struct btrfs_root **sub_root)
39279cc3 4764{
4df27c4d
YZ		 4765 struct btrfs_path *path;
4766 struct btrfs_root *new_root;
4767 struct btrfs_root_ref *ref;
4768 struct extent_buffer *leaf;
4769 int ret;
4770 int err = 0;
39279cc3 4771
4df27c4d
YZ		 4772 path = btrfs_alloc_path();
4773 if (!path) {
4774 err = -ENOMEM;
4775 goto out;
4776 }
39279cc3 4777
4df27c4d
YZ		 4778 err = -ENOENT;
4779 ret = btrfs_find_root_ref(root->fs_info->tree_root, path,
4780 BTRFS_I(dir)->root->root_key.objectid,
4781 location->objectid);
4782 if (ret) {
4783 if (ret < 0)
4784 err = ret;
4785 goto out;
4786 }
39279cc3 4787
4df27c4d
YZ		 4788 leaf = path->nodes[0];
4789 ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_ref);
33345d01 4790 if (btrfs_root_ref_dirid(leaf, ref) != btrfs_ino(dir) ||
4df27c4d
YZ		 4791 btrfs_root_ref_name_len(leaf, ref) != dentry->d_name.len)
4792 goto out;
39279cc3 4793
4df27c4d
YZ		 4794 ret = memcmp_extent_buffer(leaf, dentry->d_name.name,
4795 (unsigned long)(ref + 1),
4796 dentry->d_name.len);
4797 if (ret)
4798 goto out;
4799
b3b4aa74 4800 btrfs_release_path(path);
4df27c4d
YZ		 4801
4802 new_root = btrfs_read_fs_root_no_name(root->fs_info, location);
4803 if (IS_ERR(new_root)) {
4804 err = PTR_ERR(new_root);
4805 goto out;
4806 }
4807
4808 if (btrfs_root_refs(&new_root->root_item) == 0) {
4809 err = -ENOENT;
4810 goto out;
4811 }
4812
4813 *sub_root = new_root;
4814 location->objectid = btrfs_root_dirid(&new_root->root_item);
4815 location->type = BTRFS_INODE_ITEM_KEY;
4816 location->offset = 0;
4817 err = 0;
4818out:
4819 btrfs_free_path(path);
4820 return err;
39279cc3
CM		 4821}
4822
5d4f98a2
YZ		 4823static void inode_tree_add(struct inode *inode)
4824{
4825 struct btrfs_root *root = BTRFS_I(inode)->root;
4826 struct btrfs_inode *entry;
03e860bd
FNP		 4827 struct rb_node **p;
4828 struct rb_node *parent;
33345d01 4829 u64 ino = btrfs_ino(inode);
03e860bd
FNP		 4830again:
4831 p = &root->inode_tree.rb_node;
4832 parent = NULL;
5d4f98a2 4833
1d3382cb 4834 if (inode_unhashed(inode))
76dda93c
YZ		 4835 return;
4836
5d4f98a2
YZ		 4837 spin_lock(&root->inode_lock);
4838 while (*p) {
4839 parent = *p;
4840 entry = rb_entry(parent, struct btrfs_inode, rb_node);
4841
33345d01 4842 if (ino < btrfs_ino(&entry->vfs_inode))
03e860bd 4843 p = &parent->rb_left;
33345d01 4844 else if (ino > btrfs_ino(&entry->vfs_inode))
03e860bd 4845 p = &parent->rb_right;
5d4f98a2
YZ		 4846 else {
4847 WARN_ON(!(entry->vfs_inode.i_state &
a4ffdde6 4848 (I_WILL_FREE | I_FREEING)));
03e860bd
FNP		 4849 rb_erase(parent, &root->inode_tree);
4850 RB_CLEAR_NODE(parent);
4851 spin_unlock(&root->inode_lock);
4852 goto again;
5d4f98a2
YZ		 4853 }
4854 }
4855 rb_link_node(&BTRFS_I(inode)->rb_node, parent, p);
4856 rb_insert_color(&BTRFS_I(inode)->rb_node, &root->inode_tree);
4857 spin_unlock(&root->inode_lock);
4858}
4859
4860static void inode_tree_del(struct inode *inode)
4861{
4862 struct btrfs_root *root = BTRFS_I(inode)->root;
76dda93c 4863 int empty = 0;
5d4f98a2 4864
03e860bd 4865 spin_lock(&root->inode_lock);
5d4f98a2 4866 if (!RB_EMPTY_NODE(&BTRFS_I(inode)->rb_node)) {
5d4f98a2 4867 rb_erase(&BTRFS_I(inode)->rb_node, &root->inode_tree);
5d4f98a2 4868 RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node);
76dda93c 4869 empty = RB_EMPTY_ROOT(&root->inode_tree);
5d4f98a2 4870 }
03e860bd 4871 spin_unlock(&root->inode_lock);
76dda93c 4872
0af3d00b
JB		 4873 /*
4874 * Free space cache has inodes in the tree root, but the tree root has a
4875 * root_refs of 0, so this could end up dropping the tree root as a
4876 * snapshot, so we need the extra !root->fs_info->tree_root check to
4877 * make sure we don't drop it.
4878 */
4879 if (empty && btrfs_root_refs(&root->root_item) == 0 &&
4880 root != root->fs_info->tree_root) {
76dda93c
YZ		 4881 synchronize_srcu(&root->fs_info->subvol_srcu);
4882 spin_lock(&root->inode_lock);
4883 empty = RB_EMPTY_ROOT(&root->inode_tree);
4884 spin_unlock(&root->inode_lock);
4885 if (empty)
4886 btrfs_add_dead_root(root);
4887 }
4888}
4889
143bede5 4890void btrfs_invalidate_inodes(struct btrfs_root *root)
76dda93c
YZ		 4891{
4892 struct rb_node *node;
4893 struct rb_node *prev;
4894 struct btrfs_inode *entry;
4895 struct inode *inode;
4896 u64 objectid = 0;
4897
4898 WARN_ON(btrfs_root_refs(&root->root_item) != 0);
4899
4900 spin_lock(&root->inode_lock);
4901again:
4902 node = root->inode_tree.rb_node;
4903 prev = NULL;
4904 while (node) {
4905 prev = node;
4906 entry = rb_entry(node, struct btrfs_inode, rb_node);
4907
33345d01 4908 if (objectid < btrfs_ino(&entry->vfs_inode))
76dda93c 4909 node = node->rb_left;
33345d01 4910 else if (objectid > btrfs_ino(&entry->vfs_inode))
76dda93c
YZ		 4911 node = node->rb_right;
4912 else
4913 break;
4914 }
4915 if (!node) {
4916 while (prev) {
4917 entry = rb_entry(prev, struct btrfs_inode, rb_node);
33345d01 4918 if (objectid <= btrfs_ino(&entry->vfs_inode)) {
76dda93c
YZ		 4919 node = prev;
4920 break;
4921 }
4922 prev = rb_next(prev);
4923 }
4924 }
4925 while (node) {
4926 entry = rb_entry(node, struct btrfs_inode, rb_node);
33345d01 4927 objectid = btrfs_ino(&entry->vfs_inode) + 1;
76dda93c
YZ		 4928 inode = igrab(&entry->vfs_inode);
4929 if (inode) {
4930 spin_unlock(&root->inode_lock);
4931 if (atomic_read(&inode->i_count) > 1)
4932 d_prune_aliases(inode);
4933 /*
45321ac5 4934 * btrfs_drop_inode will have it removed from
76dda93c
YZ		 4935 * the inode cache when its usage count
4936 * hits zero.
4937 */
4938 iput(inode);
4939 cond_resched();
4940 spin_lock(&root->inode_lock);
4941 goto again;
4942 }
4943
4944 if (cond_resched_lock(&root->inode_lock))
4945 goto again;
4946
4947 node = rb_next(node);
4948 }
4949 spin_unlock(&root->inode_lock);
5d4f98a2
YZ		 4950}
4951
e02119d5
CM		 4952static int btrfs_init_locked_inode(struct inode *inode, void *p)
4953{
4954 struct btrfs_iget_args *args = p;
4955 inode->i_ino = args->ino;
e02119d5 4956 BTRFS_I(inode)->root = args->root;
39279cc3
CM		 4957 return 0;
4958}
4959
4960static int btrfs_find_actor(struct inode *inode, void *opaque)
4961{
4962 struct btrfs_iget_args *args = opaque;
33345d01 4963 return args->ino == btrfs_ino(inode) &&
d397712b 4964 args->root == BTRFS_I(inode)->root;
39279cc3
CM		 4965}
4966
5d4f98a2
YZ		 4967static struct inode *btrfs_iget_locked(struct super_block *s,
4968 u64 objectid,
4969 struct btrfs_root *root)
39279cc3
CM		 4970{
4971 struct inode *inode;
4972 struct btrfs_iget_args args;
4973 args.ino = objectid;
4974 args.root = root;
4975
4976 inode = iget5_locked(s, objectid, btrfs_find_actor,
4977 btrfs_init_locked_inode,
4978 (void *)&args);
4979 return inode;
4980}
4981
1a54ef8c
BR		 4982/* Get an inode object given its location and corresponding root.
4983 * Returns in *is_new if the inode was read from disk
4984 */
4985struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location,
73f73415 4986 struct btrfs_root *root, int *new)
1a54ef8c
BR		 4987{
4988 struct inode *inode;
4989
4990 inode = btrfs_iget_locked(s, location->objectid, root);
4991 if (!inode)
5d4f98a2 4992 return ERR_PTR(-ENOMEM);
1a54ef8c
BR		 4993
4994 if (inode->i_state & I_NEW) {
4995 BTRFS_I(inode)->root = root;
4996 memcpy(&BTRFS_I(inode)->location, location, sizeof(*location));
4997 btrfs_read_locked_inode(inode);
1748f843
MF		 4998 if (!is_bad_inode(inode)) {
4999 inode_tree_add(inode);
5000 unlock_new_inode(inode);
5001 if (new)
5002 *new = 1;
5003 } else {
e0b6d65b
ST		 5004 unlock_new_inode(inode);
5005 iput(inode);
5006 inode = ERR_PTR(-ESTALE);
1748f843
MF		 5007 }
5008 }
5009
1a54ef8c
BR		 5010 return inode;
5011}
5012
4df27c4d
YZ		 5013static struct inode *new_simple_dir(struct super_block *s,
5014 struct btrfs_key *key,
5015 struct btrfs_root *root)
5016{
5017 struct inode *inode = new_inode(s);
5018
5019 if (!inode)
5020 return ERR_PTR(-ENOMEM);
5021
4df27c4d
YZ		 5022 BTRFS_I(inode)->root = root;
5023 memcpy(&BTRFS_I(inode)->location, key, sizeof(*key));
72ac3c0d 5024 set_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags);
4df27c4d
YZ		 5025
5026 inode->i_ino = BTRFS_EMPTY_SUBVOL_DIR_OBJECTID;
848cce0d 5027 inode->i_op = &btrfs_dir_ro_inode_operations;
4df27c4d
YZ		 5028 inode->i_fop = &simple_dir_operations;
5029 inode->i_mode = S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO;
5030 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
5031
5032 return inode;
5033}
5034
3de4586c 5035struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry)
39279cc3 5036{
d397712b 5037 struct inode *inode;
4df27c4d 5038 struct btrfs_root *root = BTRFS_I(dir)->root;
39279cc3
CM		 5039 struct btrfs_root *sub_root = root;
5040 struct btrfs_key location;
76dda93c 5041 int index;
b4aff1f8 5042 int ret = 0;
39279cc3
CM		 5043
5044 if (dentry->d_name.len > BTRFS_NAME_LEN)
5045 return ERR_PTR(-ENAMETOOLONG);
5f39d397 5046
39e3c955 5047 ret = btrfs_inode_by_name(dir, dentry, &location);
39279cc3
CM		 5048 if (ret < 0)
5049 return ERR_PTR(ret);
5f39d397 5050
4df27c4d
YZ		 5051 if (location.objectid == 0)
5052 return NULL;
5053
5054 if (location.type == BTRFS_INODE_ITEM_KEY) {
73f73415 5055 inode = btrfs_iget(dir->i_sb, &location, root, NULL);
4df27c4d
YZ		 5056 return inode;
5057 }
5058
5059 BUG_ON(location.type != BTRFS_ROOT_ITEM_KEY);
5060
76dda93c 5061 index = srcu_read_lock(&root->fs_info->subvol_srcu);
4df27c4d
YZ		 5062 ret = fixup_tree_root_location(root, dir, dentry,
5063 &location, &sub_root);
5064 if (ret < 0) {
5065 if (ret != -ENOENT)
5066 inode = ERR_PTR(ret);
5067 else
5068 inode = new_simple_dir(dir->i_sb, &location, sub_root);
5069 } else {
73f73415 5070 inode = btrfs_iget(dir->i_sb, &location, sub_root, NULL);
39279cc3 5071 }
76dda93c
YZ		 5072 srcu_read_unlock(&root->fs_info->subvol_srcu, index);
5073
34d19bad 5074 if (!IS_ERR(inode) && root != sub_root) {
c71bf099
YZ		 5075 down_read(&root->fs_info->cleanup_work_sem);
5076 if (!(inode->i_sb->s_flags & MS_RDONLY))
66b4ffd1 5077 ret = btrfs_orphan_cleanup(sub_root);
c71bf099 5078 up_read(&root->fs_info->cleanup_work_sem);
66b4ffd1
JB		 5079 if (ret)
5080 inode = ERR_PTR(ret);
c71bf099
YZ		 5081 }
5082
3de4586c
CM		 5083 return inode;
5084}
5085
fe15ce44 5086static int btrfs_dentry_delete(const struct dentry *dentry)
76dda93c
YZ		 5087{
5088 struct btrfs_root *root;
848cce0d 5089 struct inode *inode = dentry->d_inode;
76dda93c 5090
848cce0d
LZ		 5091 if (!inode && !IS_ROOT(dentry))
5092 inode = dentry->d_parent->d_inode;
76dda93c 5093
848cce0d
LZ		 5094 if (inode) {
5095 root = BTRFS_I(inode)->root;
efefb143
YZ		 5096 if (btrfs_root_refs(&root->root_item) == 0)
5097 return 1;
848cce0d
LZ		 5098
5099 if (btrfs_ino(inode) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
5100 return 1;
efefb143 5101 }
76dda93c
YZ		 5102 return 0;
5103}
5104
b4aff1f8
JB		 5105static void btrfs_dentry_release(struct dentry *dentry)
5106{
5107 if (dentry->d_fsdata)
5108 kfree(dentry->d_fsdata);
5109}
5110
3de4586c 5111static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
00cd8dd3 5112 unsigned int flags)
3de4586c 5113{
a66e7cc6
JB		 5114 struct dentry *ret;
5115
5116 ret = d_splice_alias(btrfs_lookup_dentry(dir, dentry), dentry);
a66e7cc6 5117 return ret;
39279cc3
CM		 5118}
5119
16cdcec7 5120unsigned char btrfs_filetype_table[] = {
39279cc3
CM		 5121 DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
5122};
5123
cbdf5a24
DW		 5124static int btrfs_real_readdir(struct file *filp, void *dirent,
5125 filldir_t filldir)
39279cc3 5126{
496ad9aa 5127 struct inode *inode = file_inode(filp);
39279cc3
CM		 5128 struct btrfs_root *root = BTRFS_I(inode)->root;
5129 struct btrfs_item *item;
5130 struct btrfs_dir_item *di;
5131 struct btrfs_key key;
5f39d397 5132 struct btrfs_key found_key;
39279cc3 5133 struct btrfs_path *path;
16cdcec7
MX		 5134 struct list_head ins_list;
5135 struct list_head del_list;
39279cc3 5136 int ret;
5f39d397 5137 struct extent_buffer *leaf;
39279cc3 5138 int slot;
39279cc3
CM		 5139 unsigned char d_type;
5140 int over = 0;
5141 u32 di_cur;
5142 u32 di_total;
5143 u32 di_len;
5144 int key_type = BTRFS_DIR_INDEX_KEY;
5f39d397
CM		 5145 char tmp_name[32];
5146 char *name_ptr;
5147 int name_len;
16cdcec7 5148 int is_curr = 0; /* filp->f_pos points to the current index? */
39279cc3
CM		 5149
5150 /* FIXME, use a real flag for deciding about the key type */
5151 if (root->fs_info->tree_root == root)
5152 key_type = BTRFS_DIR_ITEM_KEY;
5f39d397 5153
3954401f
CM		 5154 /* special case for "." */
5155 if (filp->f_pos == 0) {
3765fefa
HS		 5156 over = filldir(dirent, ".", 1,
5157 filp->f_pos, btrfs_ino(inode), DT_DIR);
3954401f
CM		 5158 if (over)
5159 return 0;
5160 filp->f_pos = 1;
5161 }
3954401f
CM		 5162 /* special case for .., just use the back ref */
5163 if (filp->f_pos == 1) {
5ecc7e5d 5164 u64 pino = parent_ino(filp->f_path.dentry);
3954401f 5165 over = filldir(dirent, "..", 2,
3765fefa 5166 filp->f_pos, pino, DT_DIR);
3954401f 5167 if (over)
49593bfa 5168 return 0;
3954401f
CM		 5169 filp->f_pos = 2;
5170 }
49593bfa 5171 path = btrfs_alloc_path();
16cdcec7
MX		 5172 if (!path)
5173 return -ENOMEM;
ff5714cc 5174
026fd317 5175 path->reada = 1;
49593bfa 5176
16cdcec7
MX		 5177 if (key_type == BTRFS_DIR_INDEX_KEY) {
5178 INIT_LIST_HEAD(&ins_list);
5179 INIT_LIST_HEAD(&del_list);
5180 btrfs_get_delayed_items(inode, &ins_list, &del_list);
5181 }
5182
39279cc3
CM		 5183 btrfs_set_key_type(&key, key_type);
5184 key.offset = filp->f_pos;
33345d01 5185 key.objectid = btrfs_ino(inode);
5f39d397 5186
39279cc3
CM		 5187 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
5188 if (ret < 0)
5189 goto err;
49593bfa
DW		 5190
5191 while (1) {
5f39d397 5192 leaf = path->nodes[0];
39279cc3 5193 slot = path->slots[0];
b9e03af0
LZ		 5194 if (slot >= btrfs_header_nritems(leaf)) {
5195 ret = btrfs_next_leaf(root, path);
5196 if (ret < 0)
5197 goto err;
5198 else if (ret > 0)
5199 break;
5200 continue;
39279cc3 5201 }
3de4586c 5202
5f39d397
CM		 5203 item = btrfs_item_nr(leaf, slot);
5204 btrfs_item_key_to_cpu(leaf, &found_key, slot);
5205
5206 if (found_key.objectid != key.objectid)
39279cc3 5207 break;
5f39d397 5208 if (btrfs_key_type(&found_key) != key_type)
39279cc3 5209 break;
5f39d397 5210 if (found_key.offset < filp->f_pos)
b9e03af0 5211 goto next;
16cdcec7
MX		 5212 if (key_type == BTRFS_DIR_INDEX_KEY &&
5213 btrfs_should_delete_dir_index(&del_list,
5214 found_key.offset))
5215 goto next;
5f39d397
CM		 5216
5217 filp->f_pos = found_key.offset;
16cdcec7 5218 is_curr = 1;
49593bfa 5219
39279cc3
CM		 5220 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
5221 di_cur = 0;
5f39d397 5222 di_total = btrfs_item_size(leaf, item);
49593bfa
DW		 5223
5224 while (di_cur < di_total) {
5f39d397
CM		 5225 struct btrfs_key location;
5226
22a94d44
JB		 5227 if (verify_dir_item(root, leaf, di))
5228 break;
5229
5f39d397 5230 name_len = btrfs_dir_name_len(leaf, di);
49593bfa 5231 if (name_len <= sizeof(tmp_name)) {
5f39d397
CM		 5232 name_ptr = tmp_name;
5233 } else {
5234 name_ptr = kmalloc(name_len, GFP_NOFS);
49593bfa
DW		 5235 if (!name_ptr) {
5236 ret = -ENOMEM;
5237 goto err;
5238 }
5f39d397
CM		 5239 }
5240 read_extent_buffer(leaf, name_ptr,
5241 (unsigned long)(di + 1), name_len);
5242
5243 d_type = btrfs_filetype_table[btrfs_dir_type(leaf, di)];
5244 btrfs_dir_item_key_to_cpu(leaf, di, &location);
3de4586c 5245
fede766f 5246
3de4586c 5247 /* is this a reference to our own snapshot? If so
8c9c2bf7
AJ		 5248 * skip it.
5249 *
5250 * In contrast to old kernels, we insert the snapshot's
5251 * dir item and dir index after it has been created, so
5252 * we won't find a reference to our own snapshot. We
5253 * still keep the following code for backward
5254 * compatibility.
3de4586c
CM		 5255 */
5256 if (location.type == BTRFS_ROOT_ITEM_KEY &&
5257 location.objectid == root->root_key.objectid) {
5258 over = 0;
5259 goto skip;
5260 }
5f39d397 5261 over = filldir(dirent, name_ptr, name_len,
49593bfa 5262 found_key.offset, location.objectid,
39279cc3 5263 d_type);
5f39d397 5264
3de4586c 5265skip:
5f39d397
CM		 5266 if (name_ptr != tmp_name)
5267 kfree(name_ptr);
5268
39279cc3
CM		 5269 if (over)
5270 goto nopos;
5103e947 5271 di_len = btrfs_dir_name_len(leaf, di) +
49593bfa 5272 btrfs_dir_data_len(leaf, di) + sizeof(*di);
39279cc3
CM		 5273 di_cur += di_len;
5274 di = (struct btrfs_dir_item *)((char *)di + di_len);
5275 }
b9e03af0
LZ		 5276next:
5277 path->slots[0]++;
39279cc3 5278 }
49593bfa 5279
16cdcec7
MX		 5280 if (key_type == BTRFS_DIR_INDEX_KEY) {
5281 if (is_curr)
5282 filp->f_pos++;
5283 ret = btrfs_readdir_delayed_dir_index(filp, dirent, filldir,
5284 &ins_list);
5285 if (ret)
5286 goto nopos;
5287 }
5288
49593bfa 5289 /* Reached end of directory/root. Bump pos past the last item. */
5e591a07 5290 if (key_type == BTRFS_DIR_INDEX_KEY)
406266ab
JE		 5291 /*
5292 * 32-bit glibc will use getdents64, but then strtol -
5293 * so the last number we can serve is this.
5294 */
5295 filp->f_pos = 0x7fffffff;
5e591a07
YZ		 5296 else
5297 filp->f_pos++;
39279cc3
CM		 5298nopos:
5299 ret = 0;
5300err:
16cdcec7
MX		 5301 if (key_type == BTRFS_DIR_INDEX_KEY)
5302 btrfs_put_delayed_items(&ins_list, &del_list);
39279cc3 5303 btrfs_free_path(path);
39279cc3
CM		 5304 return ret;
5305}
5306
a9185b41 5307int btrfs_write_inode(struct inode *inode, struct writeback_control *wbc)
39279cc3
CM		 5308{
5309 struct btrfs_root *root = BTRFS_I(inode)->root;
5310 struct btrfs_trans_handle *trans;
5311 int ret = 0;
0af3d00b 5312 bool nolock = false;
39279cc3 5313
72ac3c0d 5314 if (test_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags))
4ca8b41e
CM		 5315 return 0;
5316
83eea1f1 5317 if (btrfs_fs_closing(root->fs_info) && btrfs_is_free_space_inode(inode))
82d5902d 5318 nolock = true;
0af3d00b 5319
a9185b41 5320 if (wbc->sync_mode == WB_SYNC_ALL) {
0af3d00b 5321 if (nolock)
7a7eaa40 5322 trans = btrfs_join_transaction_nolock(root);
0af3d00b 5323 else
7a7eaa40 5324 trans = btrfs_join_transaction(root);
3612b495
TI		 5325 if (IS_ERR(trans))
5326 return PTR_ERR(trans);
a698d075 5327 ret = btrfs_commit_transaction(trans, root);
39279cc3
CM		 5328 }
5329 return ret;
5330}
5331
5332/*
54aa1f4d 5333 * This is somewhat expensive, updating the tree every time the
39279cc3
CM		 5334 * inode changes. But, it is most likely to find the inode in cache.
5335 * FIXME, needs more benchmarking...there are no reasons other than performance
5336 * to keep or drop this code.
5337 */
22c44fe6 5338int btrfs_dirty_inode(struct inode *inode)
39279cc3
CM		 5339{
5340 struct btrfs_root *root = BTRFS_I(inode)->root;
5341 struct btrfs_trans_handle *trans;
8929ecfa
YZ		 5342 int ret;
5343
72ac3c0d 5344 if (test_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags))
22c44fe6 5345 return 0;
39279cc3 5346
7a7eaa40 5347 trans = btrfs_join_transaction(root);
22c44fe6
JB		 5348 if (IS_ERR(trans))
5349 return PTR_ERR(trans);
8929ecfa
YZ		 5350
5351 ret = btrfs_update_inode(trans, root, inode);
94b60442
CM		 5352 if (ret && ret == -ENOSPC) {
5353 /* whoops, lets try again with the full transaction */
5354 btrfs_end_transaction(trans, root);
5355 trans = btrfs_start_transaction(root, 1);
22c44fe6
JB		 5356 if (IS_ERR(trans))
5357 return PTR_ERR(trans);
8929ecfa 5358
94b60442 5359 ret = btrfs_update_inode(trans, root, inode);
94b60442 5360 }
39279cc3 5361 btrfs_end_transaction(trans, root);
16cdcec7
MX		 5362 if (BTRFS_I(inode)->delayed_node)
5363 btrfs_balance_delayed_items(root);
22c44fe6
JB		 5364
5365 return ret;
5366}
5367
5368/*
5369 * This is a copy of file_update_time. We need this so we can return error on
5370 * ENOSPC for updating the inode in the case of file write and mmap writes.
5371 */
e41f941a
JB		 5372static int btrfs_update_time(struct inode *inode, struct timespec *now,
5373 int flags)
22c44fe6 5374{
2bc55652
AB		 5375 struct btrfs_root *root = BTRFS_I(inode)->root;
5376
5377 if (btrfs_root_readonly(root))
5378 return -EROFS;
5379
e41f941a 5380 if (flags & S_VERSION)
22c44fe6 5381 inode_inc_iversion(inode);
e41f941a
JB		 5382 if (flags & S_CTIME)
5383 inode->i_ctime = *now;
5384 if (flags & S_MTIME)
5385 inode->i_mtime = *now;
5386 if (flags & S_ATIME)
5387 inode->i_atime = *now;
5388 return btrfs_dirty_inode(inode);
39279cc3
CM		 5389}
5390
d352ac68
CM		 5391/*
5392 * find the highest existing sequence number in a directory
5393 * and then set the in-memory index_cnt variable to reflect
5394 * free sequence numbers
5395 */
aec7477b
JB		 5396static int btrfs_set_inode_index_count(struct inode *inode)
5397{
5398 struct btrfs_root *root = BTRFS_I(inode)->root;
5399 struct btrfs_key key, found_key;
5400 struct btrfs_path *path;
5401 struct extent_buffer *leaf;
5402 int ret;
5403
33345d01 5404 key.objectid = btrfs_ino(inode);
aec7477b
JB		 5405 btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY);
5406 key.offset = (u64)-1;
5407
5408 path = btrfs_alloc_path();
5409 if (!path)
5410 return -ENOMEM;
5411
5412 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
5413 if (ret < 0)
5414 goto out;
5415 /* FIXME: we should be able to handle this */
5416 if (ret == 0)
5417 goto out;
5418 ret = 0;
5419
5420 /*
5421 * MAGIC NUMBER EXPLANATION:
5422 * since we search a directory based on f_pos we have to start at 2
5423 * since '.' and '..' have f_pos of 0 and 1 respectively, so everybody
5424 * else has to start at 2
5425 */
5426 if (path->slots[0] == 0) {
5427 BTRFS_I(inode)->index_cnt = 2;
5428 goto out;
5429 }
5430
5431 path->slots[0]--;
5432
5433 leaf = path->nodes[0];
5434 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
5435
33345d01 5436 if (found_key.objectid != btrfs_ino(inode) ||
aec7477b
JB		 5437 btrfs_key_type(&found_key) != BTRFS_DIR_INDEX_KEY) {
5438 BTRFS_I(inode)->index_cnt = 2;
5439 goto out;
5440 }
5441
5442 BTRFS_I(inode)->index_cnt = found_key.offset + 1;
5443out:
5444 btrfs_free_path(path);
5445 return ret;
5446}
5447
d352ac68
CM		 5448/*
5449 * helper to find a free sequence number in a given directory. This current
5450 * code is very simple, later versions will do smarter things in the btree
5451 */
3de4586c 5452int btrfs_set_inode_index(struct inode *dir, u64 *index)
aec7477b
JB		 5453{
5454 int ret = 0;
5455
5456 if (BTRFS_I(dir)->index_cnt == (u64)-1) {
16cdcec7
MX		 5457 ret = btrfs_inode_delayed_dir_index_count(dir);
5458 if (ret) {
5459 ret = btrfs_set_inode_index_count(dir);
5460 if (ret)
5461 return ret;
5462 }
aec7477b
JB		 5463 }
5464
00e4e6b3 5465 *index = BTRFS_I(dir)->index_cnt;
aec7477b
JB		 5466 BTRFS_I(dir)->index_cnt++;
5467
5468 return ret;
5469}
5470
39279cc3
CM		 5471static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
5472 struct btrfs_root *root,
aec7477b 5473 struct inode *dir,
9c58309d 5474 const char *name, int name_len,
175a4eb7
AV		 5475 u64 ref_objectid, u64 objectid,
5476 umode_t mode, u64 *index)
39279cc3
CM		 5477{
5478 struct inode *inode;
5f39d397 5479 struct btrfs_inode_item *inode_item;
39279cc3 5480 struct btrfs_key *location;
5f39d397 5481 struct btrfs_path *path;
9c58309d
CM		 5482 struct btrfs_inode_ref *ref;
5483 struct btrfs_key key[2];
5484 u32 sizes[2];
5485 unsigned long ptr;
39279cc3
CM		 5486 int ret;
5487 int owner;
5488
5f39d397 5489 path = btrfs_alloc_path();
d8926bb3
MF		 5490 if (!path)
5491 return ERR_PTR(-ENOMEM);
5f39d397 5492
39279cc3 5493 inode = new_inode(root->fs_info->sb);
8fb27640
YS		 5494 if (!inode) {
5495 btrfs_free_path(path);
39279cc3 5496 return ERR_PTR(-ENOMEM);
8fb27640 5497 }
39279cc3 5498
581bb050
LZ		 5499 /*
5500 * we have to initialize this early, so we can reclaim the inode
5501 * number if we fail afterwards in this function.
5502 */
5503 inode->i_ino = objectid;
5504
aec7477b 5505 if (dir) {
1abe9b8a 5506 trace_btrfs_inode_request(dir);
5507
3de4586c 5508 ret = btrfs_set_inode_index(dir, index);
09771430 5509 if (ret) {
8fb27640 5510 btrfs_free_path(path);
09771430 5511 iput(inode);
aec7477b 5512 return ERR_PTR(ret);
09771430 5513 }
aec7477b
JB		 5514 }
5515 /*
5516 * index_cnt is ignored for everything but a dir,
5517 * btrfs_get_inode_index_count has an explanation for the magic
5518 * number
5519 */
5520 BTRFS_I(inode)->index_cnt = 2;
39279cc3 5521 BTRFS_I(inode)->root = root;
e02119d5 5522 BTRFS_I(inode)->generation = trans->transid;
76195853 5523 inode->i_generation = BTRFS_I(inode)->generation;
b888db2b 5524
5dc562c5
JB		 5525 /*
5526 * We could have gotten an inode number from somebody who was fsynced
5527 * and then removed in this same transaction, so let's just set full
5528 * sync since it will be a full sync anyway and this will blow away the
5529 * old info in the log.
5530 */
5531 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags);
5532
569254b0 5533 if (S_ISDIR(mode))
39279cc3
CM		 5534 owner = 0;
5535 else
5536 owner = 1;
9c58309d
CM		 5537
5538 key[0].objectid = objectid;
5539 btrfs_set_key_type(&key[0], BTRFS_INODE_ITEM_KEY);
5540 key[0].offset = 0;
5541
f186373f
MF		 5542 /*
5543 * Start new inodes with an inode_ref. This is slightly more
5544 * efficient for small numbers of hard links since they will
5545 * be packed into one item. Extended refs will kick in if we
5546 * add more hard links than can fit in the ref item.
5547 */
9c58309d
CM		 5548 key[1].objectid = objectid;
5549 btrfs_set_key_type(&key[1], BTRFS_INODE_REF_KEY);
5550 key[1].offset = ref_objectid;
5551
5552 sizes[0] = sizeof(struct btrfs_inode_item);
5553 sizes[1] = name_len + sizeof(*ref);
5554
b9473439 5555 path->leave_spinning = 1;
9c58309d
CM		 5556 ret = btrfs_insert_empty_items(trans, root, path, key, sizes, 2);
5557 if (ret != 0)
5f39d397
CM		 5558 goto fail;
5559
ecc11fab 5560 inode_init_owner(inode, dir, mode);
a76a3cd4 5561 inode_set_bytes(inode, 0);
39279cc3 5562 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
5f39d397
CM		 5563 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
5564 struct btrfs_inode_item);
293f7e07
LZ		 5565 memset_extent_buffer(path->nodes[0], 0, (unsigned long)inode_item,
5566 sizeof(*inode_item));
e02119d5 5567 fill_inode_item(trans, path->nodes[0], inode_item, inode);
9c58309d
CM		 5568
5569 ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1,
5570 struct btrfs_inode_ref);
5571 btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len);
00e4e6b3 5572 btrfs_set_inode_ref_index(path->nodes[0], ref, *index);
9c58309d
CM		 5573 ptr = (unsigned long)(ref + 1);
5574 write_extent_buffer(path->nodes[0], name, ptr, name_len);
5575
5f39d397
CM		 5576 btrfs_mark_buffer_dirty(path->nodes[0]);
5577 btrfs_free_path(path);
5578
39279cc3
CM		 5579 location = &BTRFS_I(inode)->location;
5580 location->objectid = objectid;
39279cc3
CM		 5581 location->offset = 0;
5582 btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
5583
6cbff00f
CH		 5584 btrfs_inherit_iflags(inode, dir);
5585
569254b0 5586 if (S_ISREG(mode)) {
94272164
CM		 5587 if (btrfs_test_opt(root, NODATASUM))
5588 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
213490b3 5589 if (btrfs_test_opt(root, NODATACOW))
f2bdf9a8
JB		 5590 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW |
5591 BTRFS_INODE_NODATASUM;
94272164
CM		 5592 }
5593
39279cc3 5594 insert_inode_hash(inode);
5d4f98a2 5595 inode_tree_add(inode);
1abe9b8a 5596
5597 trace_btrfs_inode_new(inode);
1973f0fa 5598 btrfs_set_inode_last_trans(trans, inode);
1abe9b8a 5599
8ea05e3a
AB		 5600 btrfs_update_root_times(trans, root);
5601
39279cc3 5602 return inode;
5f39d397 5603fail:
aec7477b
JB		 5604 if (dir)
5605 BTRFS_I(dir)->index_cnt--;
5f39d397 5606 btrfs_free_path(path);
09771430 5607 iput(inode);
5f39d397 5608 return ERR_PTR(ret);
39279cc3
CM		 5609}
5610
5611static inline u8 btrfs_inode_type(struct inode *inode)
5612{
5613 return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT];
5614}
5615
d352ac68
CM		 5616/*
5617 * utility function to add 'inode' into 'parent_inode' with
5618 * a give name and a given sequence number.
5619 * if 'add_backref' is true, also insert a backref from the
5620 * inode to the parent directory.
5621 */
e02119d5
CM		 5622int btrfs_add_link(struct btrfs_trans_handle *trans,
5623 struct inode *parent_inode, struct inode *inode,
5624 const char *name, int name_len, int add_backref, u64 index)
39279cc3 5625{
4df27c4d 5626 int ret = 0;
39279cc3 5627 struct btrfs_key key;
e02119d5 5628 struct btrfs_root *root = BTRFS_I(parent_inode)->root;
33345d01
LZ		 5629 u64 ino = btrfs_ino(inode);
5630 u64 parent_ino = btrfs_ino(parent_inode);
5f39d397 5631
33345d01 5632 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
4df27c4d
YZ		 5633 memcpy(&key, &BTRFS_I(inode)->root->root_key, sizeof(key));
5634 } else {
33345d01 5635 key.objectid = ino;
4df27c4d
YZ		 5636 btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
5637 key.offset = 0;
5638 }
5639
33345d01 5640 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
4df27c4d
YZ		 5641 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
5642 key.objectid, root->root_key.objectid,
33345d01 5643 parent_ino, index, name, name_len);
4df27c4d 5644 } else if (add_backref) {
33345d01
LZ		 5645 ret = btrfs_insert_inode_ref(trans, root, name, name_len, ino,
5646 parent_ino, index);
4df27c4d 5647 }
39279cc3 5648
79787eaa
JM		 5649 /* Nothing to clean up yet */
5650 if (ret)
5651 return ret;
4df27c4d 5652
79787eaa
JM		 5653 ret = btrfs_insert_dir_item(trans, root, name, name_len,
5654 parent_inode, &key,
5655 btrfs_inode_type(inode), index);
9c52057c 5656 if (ret == -EEXIST || ret == -EOVERFLOW)
79787eaa
JM		 5657 goto fail_dir_item;
5658 else if (ret) {
5659 btrfs_abort_transaction(trans, root, ret);
5660 return ret;
39279cc3 5661 }
79787eaa
JM		 5662
5663 btrfs_i_size_write(parent_inode, parent_inode->i_size +
5664 name_len * 2);
0c4d2d95 5665 inode_inc_iversion(parent_inode);
79787eaa
JM		 5666 parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME;
5667 ret = btrfs_update_inode(trans, root, parent_inode);
5668 if (ret)
5669 btrfs_abort_transaction(trans, root, ret);
39279cc3 5670 return ret;
fe66a05a
CM		 5671
5672fail_dir_item:
5673 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
5674 u64 local_index;
5675 int err;
5676 err = btrfs_del_root_ref(trans, root->fs_info->tree_root,
5677 key.objectid, root->root_key.objectid,
5678 parent_ino, &local_index, name, name_len);
5679
5680 } else if (add_backref) {
5681 u64 local_index;
5682 int err;
5683
5684 err = btrfs_del_inode_ref(trans, root, name, name_len,
5685 ino, parent_ino, &local_index);
5686 }
5687 return ret;
39279cc3
CM		 5688}
5689
5690static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
a1b075d2
JB		 5691 struct inode *dir, struct dentry *dentry,
5692 struct inode *inode, int backref, u64 index)
39279cc3 5693{
a1b075d2
JB		 5694 int err = btrfs_add_link(trans, dir, inode,
5695 dentry->d_name.name, dentry->d_name.len,
5696 backref, index);
39279cc3
CM		 5697 if (err > 0)
5698 err = -EEXIST;
5699 return err;
5700}
5701
618e21d5 5702static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
1a67aafb 5703 umode_t mode, dev_t rdev)
618e21d5
JB		 5704{
5705 struct btrfs_trans_handle *trans;
5706 struct btrfs_root *root = BTRFS_I(dir)->root;
1832a6d5 5707 struct inode *inode = NULL;
618e21d5
JB		 5708 int err;
5709 int drop_inode = 0;
5710 u64 objectid;
00e4e6b3 5711 u64 index = 0;
618e21d5
JB		 5712
5713 if (!new_valid_dev(rdev))
5714 return -EINVAL;
5715
9ed74f2d
JB		 5716 /*
5717 * 2 for inode item and ref
5718 * 2 for dir items
5719 * 1 for xattr if selinux is on
5720 */
a22285a6
YZ		 5721 trans = btrfs_start_transaction(root, 5);
5722 if (IS_ERR(trans))
5723 return PTR_ERR(trans);
1832a6d5 5724
581bb050
LZ		 5725 err = btrfs_find_free_ino(root, &objectid);
5726 if (err)
5727 goto out_unlock;
5728
aec7477b 5729 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
33345d01 5730 dentry->d_name.len, btrfs_ino(dir), objectid,
d82a6f1d 5731 mode, &index);
7cf96da3
TI		 5732 if (IS_ERR(inode)) {
5733 err = PTR_ERR(inode);
618e21d5 5734 goto out_unlock;
7cf96da3 5735 }
618e21d5 5736
2a7dba39 5737 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
33268eaf
JB		 5738 if (err) {
5739 drop_inode = 1;
5740 goto out_unlock;
5741 }
5742
ad19db71
CS		 5743 /*
5744 * If the active LSM wants to access the inode during
5745 * d_instantiate it needs these. Smack checks to see
5746 * if the filesystem supports xattrs by looking at the
5747 * ops vector.
5748 */
5749
5750 inode->i_op = &btrfs_special_inode_operations;
a1b075d2 5751 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
618e21d5
JB		 5752 if (err)
5753 drop_inode = 1;
5754 else {
618e21d5 5755 init_special_inode(inode, inode->i_mode, rdev);
1b4ab1bb 5756 btrfs_update_inode(trans, root, inode);
08c422c2 5757 d_instantiate(dentry, inode);
618e21d5 5758 }
618e21d5 5759out_unlock:
7ad85bb7 5760 btrfs_end_transaction(trans, root);
b53d3f5d 5761 btrfs_btree_balance_dirty(root);
618e21d5
JB		 5762 if (drop_inode) {
5763 inode_dec_link_count(inode);
5764 iput(inode);
5765 }
618e21d5
JB		 5766 return err;
5767}
5768
39279cc3 5769static int btrfs_create(struct inode *dir, struct dentry *dentry,
ebfc3b49 5770 umode_t mode, bool excl)
39279cc3
CM		 5771{
5772 struct btrfs_trans_handle *trans;
5773 struct btrfs_root *root = BTRFS_I(dir)->root;
1832a6d5 5774 struct inode *inode = NULL;
43baa579 5775 int drop_inode_on_err = 0;
a22285a6 5776 int err;
39279cc3 5777 u64 objectid;
00e4e6b3 5778 u64 index = 0;
39279cc3 5779
9ed74f2d
JB		 5780 /*
5781 * 2 for inode item and ref
5782 * 2 for dir items
5783 * 1 for xattr if selinux is on
5784 */
a22285a6
YZ		 5785 trans = btrfs_start_transaction(root, 5);
5786 if (IS_ERR(trans))
5787 return PTR_ERR(trans);
9ed74f2d 5788
581bb050
LZ		 5789 err = btrfs_find_free_ino(root, &objectid);
5790 if (err)
5791 goto out_unlock;
5792
aec7477b 5793 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
33345d01 5794 dentry->d_name.len, btrfs_ino(dir), objectid,
d82a6f1d 5795 mode, &index);
7cf96da3
TI		 5796 if (IS_ERR(inode)) {
5797 err = PTR_ERR(inode);
39279cc3 5798 goto out_unlock;
7cf96da3 5799 }
43baa579 5800 drop_inode_on_err = 1;
39279cc3 5801
2a7dba39 5802 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
43baa579 5803 if (err)
33268eaf 5804 goto out_unlock;
33268eaf 5805
9185aa58
FB		 5806 err = btrfs_update_inode(trans, root, inode);
5807 if (err)
5808 goto out_unlock;
5809
ad19db71
CS		 5810 /*
5811 * If the active LSM wants to access the inode during
5812 * d_instantiate it needs these. Smack checks to see
5813 * if the filesystem supports xattrs by looking at the
5814 * ops vector.
5815 */
5816 inode->i_fop = &btrfs_file_operations;
5817 inode->i_op = &btrfs_file_inode_operations;
5818
a1b075d2 5819 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
39279cc3 5820 if (err)
43baa579
FB		 5821 goto out_unlock;
5822
5823 inode->i_mapping->a_ops = &btrfs_aops;
5824 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
5825 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
5826 d_instantiate(dentry, inode);
5827
39279cc3 5828out_unlock:
7ad85bb7 5829 btrfs_end_transaction(trans, root);
43baa579 5830 if (err && drop_inode_on_err) {
39279cc3
CM		 5831 inode_dec_link_count(inode);
5832 iput(inode);
5833 }
b53d3f5d 5834 btrfs_btree_balance_dirty(root);
39279cc3
CM		 5835 return err;
5836}
5837
5838static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
5839 struct dentry *dentry)
5840{
5841 struct btrfs_trans_handle *trans;
5842 struct btrfs_root *root = BTRFS_I(dir)->root;
5843 struct inode *inode = old_dentry->d_inode;
00e4e6b3 5844 u64 index;
39279cc3
CM		 5845 int err;
5846 int drop_inode = 0;
5847
4a8be425
TH		 5848 /* do not allow sys_link's with other subvols of the same device */
5849 if (root->objectid != BTRFS_I(inode)->root->objectid)
3ab3564f 5850 return -EXDEV;
4a8be425 5851
f186373f 5852 if (inode->i_nlink >= BTRFS_LINK_MAX)
c055e99e 5853 return -EMLINK;
4a8be425 5854
3de4586c 5855 err = btrfs_set_inode_index(dir, &index);
aec7477b
JB		 5856 if (err)
5857 goto fail;
5858
a22285a6 5859 /*
7e6b6465 5860 * 2 items for inode and inode ref
a22285a6 5861 * 2 items for dir items
7e6b6465 5862 * 1 item for parent inode
a22285a6 5863 */
7e6b6465 5864 trans = btrfs_start_transaction(root, 5);
a22285a6
YZ		 5865 if (IS_ERR(trans)) {
5866 err = PTR_ERR(trans);
5867 goto fail;
5868 }
5f39d397 5869
3153495d 5870 btrfs_inc_nlink(inode);
0c4d2d95 5871 inode_inc_iversion(inode);
3153495d 5872 inode->i_ctime = CURRENT_TIME;
7de9c6ee 5873 ihold(inode);
e9976151 5874 set_bit(BTRFS_INODE_COPY_EVERYTHING, &BTRFS_I(inode)->runtime_flags);
aec7477b 5875
a1b075d2 5876 err = btrfs_add_nondir(trans, dir, dentry, inode, 1, index);
5f39d397 5877
a5719521 5878 if (err) {
54aa1f4d 5879 drop_inode = 1;
a5719521 5880 } else {
10d9f309 5881 struct dentry *parent = dentry->d_parent;
a5719521 5882 err = btrfs_update_inode(trans, root, inode);
79787eaa
JM		 5883 if (err)
5884 goto fail;
08c422c2 5885 d_instantiate(dentry, inode);
6a912213 5886 btrfs_log_new_name(trans, inode, NULL, parent);
a5719521 5887 }
39279cc3 5888
7ad85bb7 5889 btrfs_end_transaction(trans, root);
1832a6d5 5890fail:
39279cc3
CM		 5891 if (drop_inode) {
5892 inode_dec_link_count(inode);
5893 iput(inode);
5894 }
b53d3f5d 5895 btrfs_btree_balance_dirty(root);
39279cc3
CM		 5896 return err;
5897}
5898
18bb1db3 5899static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
39279cc3 5900{
b9d86667 5901 struct inode *inode = NULL;
39279cc3
CM		 5902 struct btrfs_trans_handle *trans;
5903 struct btrfs_root *root = BTRFS_I(dir)->root;
5904 int err = 0;
5905 int drop_on_err = 0;
b9d86667 5906 u64 objectid = 0;
00e4e6b3 5907 u64 index = 0;
39279cc3 5908
9ed74f2d
JB		 5909 /*
5910 * 2 items for inode and ref
5911 * 2 items for dir items
5912 * 1 for xattr if selinux is on
5913 */
a22285a6
YZ		 5914 trans = btrfs_start_transaction(root, 5);
5915 if (IS_ERR(trans))
5916 return PTR_ERR(trans);
39279cc3 5917
581bb050
LZ		 5918 err = btrfs_find_free_ino(root, &objectid);
5919 if (err)
5920 goto out_fail;
5921
aec7477b 5922 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
33345d01 5923 dentry->d_name.len, btrfs_ino(dir), objectid,
d82a6f1d 5924 S_IFDIR | mode, &index);
39279cc3
CM		 5925 if (IS_ERR(inode)) {
5926 err = PTR_ERR(inode);
5927 goto out_fail;
5928 }
5f39d397 5929
39279cc3 5930 drop_on_err = 1;
33268eaf 5931
2a7dba39 5932 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
33268eaf
JB		 5933 if (err)
5934 goto out_fail;
5935
39279cc3
CM		 5936 inode->i_op = &btrfs_dir_inode_operations;
5937 inode->i_fop = &btrfs_dir_file_operations;
39279cc3 5938
dbe674a9 5939 btrfs_i_size_write(inode, 0);
39279cc3
CM		 5940 err = btrfs_update_inode(trans, root, inode);
5941 if (err)
5942 goto out_fail;
5f39d397 5943
a1b075d2
JB		 5944 err = btrfs_add_link(trans, dir, inode, dentry->d_name.name,
5945 dentry->d_name.len, 0, index);
39279cc3
CM		 5946 if (err)
5947 goto out_fail;
5f39d397 5948
39279cc3
CM		 5949 d_instantiate(dentry, inode);
5950 drop_on_err = 0;
39279cc3
CM		 5951
5952out_fail:
7ad85bb7 5953 btrfs_end_transaction(trans, root);
39279cc3
CM		 5954 if (drop_on_err)
5955 iput(inode);
b53d3f5d 5956 btrfs_btree_balance_dirty(root);
39279cc3
CM		 5957 return err;
5958}
5959
d352ac68
CM		 5960/* helper for btfs_get_extent. Given an existing extent in the tree,
5961 * and an extent that you want to insert, deal with overlap and insert
5962 * the new extent into the tree.
5963 */
3b951516
CM		 5964static int merge_extent_mapping(struct extent_map_tree *em_tree,
5965 struct extent_map *existing,
e6dcd2dc
CM		 5966 struct extent_map *em,
5967 u64 map_start, u64 map_len)
3b951516
CM		 5968{
5969 u64 start_diff;
3b951516 5970
e6dcd2dc
CM		 5971 BUG_ON(map_start < em->start || map_start >= extent_map_end(em));
5972 start_diff = map_start - em->start;
5973 em->start = map_start;
5974 em->len = map_len;
c8b97818
CM		 5975 if (em->block_start < EXTENT_MAP_LAST_BYTE &&
5976 !test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
e6dcd2dc 5977 em->block_start += start_diff;
c8b97818
CM		 5978 em->block_len -= start_diff;
5979 }
e6dcd2dc 5980 return add_extent_mapping(em_tree, em);
3b951516
CM		 5981}
5982
c8b97818
CM		 5983static noinline int uncompress_inline(struct btrfs_path *path,
5984 struct inode *inode, struct page *page,
5985 size_t pg_offset, u64 extent_offset,
5986 struct btrfs_file_extent_item *item)
5987{
5988 int ret;
5989 struct extent_buffer *leaf = path->nodes[0];
5990 char *tmp;
5991 size_t max_size;
5992 unsigned long inline_size;
5993 unsigned long ptr;
261507a0 5994 int compress_type;
c8b97818
CM		 5995
5996 WARN_ON(pg_offset != 0);
261507a0 5997 compress_type = btrfs_file_extent_compression(leaf, item);
c8b97818
CM		 5998 max_size = btrfs_file_extent_ram_bytes(leaf, item);
5999 inline_size = btrfs_file_extent_inline_item_len(leaf,
6000 btrfs_item_nr(leaf, path->slots[0]));
6001 tmp = kmalloc(inline_size, GFP_NOFS);
8d413713
TI		 6002 if (!tmp)
6003 return -ENOMEM;
c8b97818
CM		 6004 ptr = btrfs_file_extent_inline_start(item);
6005
6006 read_extent_buffer(leaf, tmp, ptr, inline_size);
6007
5b050f04 6008 max_size = min_t(unsigned long, PAGE_CACHE_SIZE, max_size);
261507a0
LZ		 6009 ret = btrfs_decompress(compress_type, tmp, page,
6010 extent_offset, inline_size, max_size);
c8b97818 6011 if (ret) {
7ac687d9 6012 char *kaddr = kmap_atomic(page);
c8b97818
CM		 6013 unsigned long copy_size = min_t(u64,
6014 PAGE_CACHE_SIZE - pg_offset,
6015 max_size - extent_offset);
6016 memset(kaddr + pg_offset, 0, copy_size);
7ac687d9 6017 kunmap_atomic(kaddr);
c8b97818
CM		 6018 }
6019 kfree(tmp);
6020 return 0;
6021}
6022
d352ac68
CM		 6023/*
6024 * a bit scary, this does extent mapping from logical file offset to the disk.
d397712b
CM		 6025 * the ugly parts come from merging extents from the disk with the in-ram
6026 * representation. This gets more complex because of the data=ordered code,
d352ac68
CM		 6027 * where the in-ram extents might be locked pending data=ordered completion.
6028 *
6029 * This also copies inline extents directly into the page.
6030 */
d397712b 6031
a52d9a80 6032struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page,
70dec807 6033 size_t pg_offset, u64 start, u64 len,
a52d9a80
CM		 6034 int create)
6035{
6036 int ret;
6037 int err = 0;
db94535d 6038 u64 bytenr;
a52d9a80
CM		 6039 u64 extent_start = 0;
6040 u64 extent_end = 0;
33345d01 6041 u64 objectid = btrfs_ino(inode);
a52d9a80 6042 u32 found_type;
f421950f 6043 struct btrfs_path *path = NULL;
a52d9a80
CM		 6044 struct btrfs_root *root = BTRFS_I(inode)->root;
6045 struct btrfs_file_extent_item *item;
5f39d397
CM		 6046 struct extent_buffer *leaf;
6047 struct btrfs_key found_key;
a52d9a80
CM		 6048 struct extent_map *em = NULL;
6049 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
d1310b2e 6050 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
a52d9a80 6051 struct btrfs_trans_handle *trans = NULL;
261507a0 6052 int compress_type;
a52d9a80 6053
a52d9a80 6054again:
890871be 6055 read_lock(&em_tree->lock);
d1310b2e 6056 em = lookup_extent_mapping(em_tree, start, len);
a061fc8d
CM		 6057 if (em)
6058 em->bdev = root->fs_info->fs_devices->latest_bdev;
890871be 6059 read_unlock(&em_tree->lock);
d1310b2e 6060
a52d9a80 6061 if (em) {
e1c4b745
CM		 6062 if (em->start > start || em->start + em->len <= start)
6063 free_extent_map(em);
6064 else if (em->block_start == EXTENT_MAP_INLINE && page)
70dec807
CM		 6065 free_extent_map(em);
6066 else
6067 goto out;
a52d9a80 6068 }
172ddd60 6069 em = alloc_extent_map();
a52d9a80 6070 if (!em) {
d1310b2e
CM		 6071 err = -ENOMEM;
6072 goto out;
a52d9a80 6073 }
e6dcd2dc 6074 em->bdev = root->fs_info->fs_devices->latest_bdev;
d1310b2e 6075 em->start = EXTENT_MAP_HOLE;
445a6944 6076 em->orig_start = EXTENT_MAP_HOLE;
d1310b2e 6077 em->len = (u64)-1;
c8b97818 6078 em->block_len = (u64)-1;
f421950f
CM		 6079
6080 if (!path) {
6081 path = btrfs_alloc_path();
026fd317
JB		 6082 if (!path) {
6083 err = -ENOMEM;
6084 goto out;
6085 }
6086 /*
6087 * Chances are we'll be called again, so go ahead and do
6088 * readahead
6089 */
6090 path->reada = 1;
f421950f
CM		 6091 }
6092
179e29e4
CM		 6093 ret = btrfs_lookup_file_extent(trans, root, path,
6094 objectid, start, trans != NULL);
a52d9a80
CM		 6095 if (ret < 0) {
6096 err = ret;
6097 goto out;
6098 }
6099
6100 if (ret != 0) {
6101 if (path->slots[0] == 0)
6102 goto not_found;
6103 path->slots[0]--;
6104 }
6105
5f39d397
CM		 6106 leaf = path->nodes[0];
6107 item = btrfs_item_ptr(leaf, path->slots[0],
a52d9a80 6108 struct btrfs_file_extent_item);
a52d9a80 6109 /* are we inside the extent that was found? */
5f39d397
CM		 6110 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6111 found_type = btrfs_key_type(&found_key);
6112 if (found_key.objectid != objectid ||
a52d9a80
CM		 6113 found_type != BTRFS_EXTENT_DATA_KEY) {
6114 goto not_found;
6115 }
6116
5f39d397
CM		 6117 found_type = btrfs_file_extent_type(leaf, item);
6118 extent_start = found_key.offset;
261507a0 6119 compress_type = btrfs_file_extent_compression(leaf, item);
d899e052
YZ		 6120 if (found_type == BTRFS_FILE_EXTENT_REG ||
6121 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
a52d9a80 6122 extent_end = extent_start +
db94535d 6123 btrfs_file_extent_num_bytes(leaf, item);
9036c102
YZ		 6124 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
6125 size_t size;
6126 size = btrfs_file_extent_inline_len(leaf, item);
fda2832f 6127 extent_end = ALIGN(extent_start + size, root->sectorsize);
9036c102
YZ		 6128 }
6129
6130 if (start >= extent_end) {
6131 path->slots[0]++;
6132 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
6133 ret = btrfs_next_leaf(root, path);
6134 if (ret < 0) {
6135 err = ret;
6136 goto out;
a52d9a80 6137 }
9036c102
YZ		 6138 if (ret > 0)
6139 goto not_found;
6140 leaf = path->nodes[0];
a52d9a80 6141 }
9036c102
YZ		 6142 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6143 if (found_key.objectid != objectid ||
6144 found_key.type != BTRFS_EXTENT_DATA_KEY)
6145 goto not_found;
6146 if (start + len <= found_key.offset)
6147 goto not_found;
6148 em->start = start;
70c8a91c 6149 em->orig_start = start;
9036c102
YZ		 6150 em->len = found_key.offset - start;
6151 goto not_found_em;
6152 }
6153
d899e052
YZ		 6154 if (found_type == BTRFS_FILE_EXTENT_REG ||
6155 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
9036c102
YZ		 6156 em->start = extent_start;
6157 em->len = extent_end - extent_start;
ff5b7ee3
YZ		 6158 em->orig_start = extent_start -
6159 btrfs_file_extent_offset(leaf, item);
b4939680
JB		 6160 em->orig_block_len = btrfs_file_extent_disk_num_bytes(leaf,
6161 item);
db94535d
CM		 6162 bytenr = btrfs_file_extent_disk_bytenr(leaf, item);
6163 if (bytenr == 0) {
5f39d397 6164 em->block_start = EXTENT_MAP_HOLE;
a52d9a80
CM		 6165 goto insert;
6166 }
261507a0 6167 if (compress_type != BTRFS_COMPRESS_NONE) {
c8b97818 6168 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
261507a0 6169 em->compress_type = compress_type;
c8b97818 6170 em->block_start = bytenr;
b4939680 6171 em->block_len = em->orig_block_len;
c8b97818
CM		 6172 } else {
6173 bytenr += btrfs_file_extent_offset(leaf, item);
6174 em->block_start = bytenr;
6175 em->block_len = em->len;
d899e052
YZ		 6176 if (found_type == BTRFS_FILE_EXTENT_PREALLOC)
6177 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
c8b97818 6178 }
a52d9a80
CM		 6179 goto insert;
6180 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
5f39d397 6181 unsigned long ptr;
a52d9a80 6182 char *map;
3326d1b0
CM		 6183 size_t size;
6184 size_t extent_offset;
6185 size_t copy_size;
a52d9a80 6186
689f9346 6187 em->block_start = EXTENT_MAP_INLINE;
c8b97818 6188 if (!page || create) {
689f9346 6189 em->start = extent_start;
9036c102 6190 em->len = extent_end - extent_start;
689f9346
Y		 6191 goto out;
6192 }
5f39d397 6193
9036c102
YZ		 6194 size = btrfs_file_extent_inline_len(leaf, item);
6195 extent_offset = page_offset(page) + pg_offset - extent_start;
70dec807 6196 copy_size = min_t(u64, PAGE_CACHE_SIZE - pg_offset,
3326d1b0 6197 size - extent_offset);
3326d1b0 6198 em->start = extent_start + extent_offset;
fda2832f 6199 em->len = ALIGN(copy_size, root->sectorsize);
b4939680 6200 em->orig_block_len = em->len;
70c8a91c 6201 em->orig_start = em->start;
261507a0 6202 if (compress_type) {
c8b97818 6203 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
261507a0
LZ		 6204 em->compress_type = compress_type;
6205 }
689f9346 6206 ptr = btrfs_file_extent_inline_start(item) + extent_offset;
179e29e4 6207 if (create == 0 && !PageUptodate(page)) {
261507a0
LZ		 6208 if (btrfs_file_extent_compression(leaf, item) !=
6209 BTRFS_COMPRESS_NONE) {
c8b97818
CM		 6210 ret = uncompress_inline(path, inode, page,
6211 pg_offset,
6212 extent_offset, item);
79787eaa 6213 BUG_ON(ret); /* -ENOMEM */
c8b97818
CM		 6214 } else {
6215 map = kmap(page);
6216 read_extent_buffer(leaf, map + pg_offset, ptr,
6217 copy_size);
93c82d57
CM		 6218 if (pg_offset + copy_size < PAGE_CACHE_SIZE) {
6219 memset(map + pg_offset + copy_size, 0,
6220 PAGE_CACHE_SIZE - pg_offset -
6221 copy_size);
6222 }
c8b97818
CM		 6223 kunmap(page);
6224 }
179e29e4
CM		 6225 flush_dcache_page(page);
6226 } else if (create && PageUptodate(page)) {
6bf7e080 6227 BUG();
179e29e4
CM		 6228 if (!trans) {
6229 kunmap(page);
6230 free_extent_map(em);
6231 em = NULL;
ff5714cc 6232
b3b4aa74 6233 btrfs_release_path(path);
7a7eaa40 6234 trans = btrfs_join_transaction(root);
ff5714cc 6235
3612b495
TI		 6236 if (IS_ERR(trans))
6237 return ERR_CAST(trans);
179e29e4
CM		 6238 goto again;
6239 }
c8b97818 6240 map = kmap(page);
70dec807 6241 write_extent_buffer(leaf, map + pg_offset, ptr,
179e29e4 6242 copy_size);
c8b97818 6243 kunmap(page);
179e29e4 6244 btrfs_mark_buffer_dirty(leaf);
a52d9a80 6245 }
d1310b2e 6246 set_extent_uptodate(io_tree, em->start,
507903b8 6247 extent_map_end(em) - 1, NULL, GFP_NOFS);
a52d9a80
CM		 6248 goto insert;
6249 } else {
31b1a2bd 6250 WARN(1, KERN_ERR "btrfs unknown found_type %d\n", found_type);
a52d9a80
CM		 6251 }
6252not_found:
6253 em->start = start;
70c8a91c 6254 em->orig_start = start;
d1310b2e 6255 em->len = len;
a52d9a80 6256not_found_em:
5f39d397 6257 em->block_start = EXTENT_MAP_HOLE;
9036c102 6258 set_bit(EXTENT_FLAG_VACANCY, &em->flags);
a52d9a80 6259insert:
b3b4aa74 6260 btrfs_release_path(path);
d1310b2e 6261 if (em->start > start || extent_map_end(em) <= start) {
d397712b
CM		 6262 printk(KERN_ERR "Btrfs: bad extent! em: [%llu %llu] passed "
6263 "[%llu %llu]\n", (unsigned long long)em->start,
6264 (unsigned long long)em->len,
6265 (unsigned long long)start,
6266 (unsigned long long)len);
a52d9a80
CM		 6267 err = -EIO;
6268 goto out;
6269 }
d1310b2e
CM		 6270
6271 err = 0;
890871be 6272 write_lock(&em_tree->lock);
a52d9a80 6273 ret = add_extent_mapping(em_tree, em);
3b951516
CM		 6274 /* it is possible that someone inserted the extent into the tree
6275 * while we had the lock dropped. It is also possible that
6276 * an overlapping map exists in the tree
6277 */
a52d9a80 6278 if (ret == -EEXIST) {
3b951516 6279 struct extent_map *existing;
e6dcd2dc
CM		 6280
6281 ret = 0;
6282
3b951516 6283 existing = lookup_extent_mapping(em_tree, start, len);
e1c4b745
CM		 6284 if (existing && (existing->start > start ||
6285 existing->start + existing->len <= start)) {
6286 free_extent_map(existing);
6287 existing = NULL;
6288 }
3b951516
CM		 6289 if (!existing) {
6290 existing = lookup_extent_mapping(em_tree, em->start,
6291 em->len);
6292 if (existing) {
6293 err = merge_extent_mapping(em_tree, existing,
e6dcd2dc
CM		 6294 em, start,
6295 root->sectorsize);
3b951516
CM		 6296 free_extent_map(existing);
6297 if (err) {
6298 free_extent_map(em);
6299 em = NULL;
6300 }
6301 } else {
6302 err = -EIO;
3b951516
CM		 6303 free_extent_map(em);
6304 em = NULL;
6305 }
6306 } else {
6307 free_extent_map(em);
6308 em = existing;
e6dcd2dc 6309 err = 0;
a52d9a80 6310 }
a52d9a80 6311 }
890871be 6312 write_unlock(&em_tree->lock);
a52d9a80 6313out:
1abe9b8a 6314
f0bd95ea
TI		 6315 if (em)
6316 trace_btrfs_get_extent(root, em);
1abe9b8a 6317
f421950f
CM		 6318 if (path)
6319 btrfs_free_path(path);
a52d9a80
CM		 6320 if (trans) {
6321 ret = btrfs_end_transaction(trans, root);
d397712b 6322 if (!err)
a52d9a80
CM		 6323 err = ret;
6324 }
a52d9a80
CM		 6325 if (err) {
6326 free_extent_map(em);
a52d9a80
CM		 6327 return ERR_PTR(err);
6328 }
79787eaa 6329 BUG_ON(!em); /* Error is always set */
a52d9a80
CM		 6330 return em;
6331}
6332
ec29ed5b
CM		 6333struct extent_map *btrfs_get_extent_fiemap(struct inode *inode, struct page *page,
6334 size_t pg_offset, u64 start, u64 len,
6335 int create)
6336{
6337 struct extent_map *em;
6338 struct extent_map *hole_em = NULL;
6339 u64 range_start = start;
6340 u64 end;
6341 u64 found;
6342 u64 found_end;
6343 int err = 0;
6344
6345 em = btrfs_get_extent(inode, page, pg_offset, start, len, create);
6346 if (IS_ERR(em))
6347 return em;
6348 if (em) {
6349 /*
f9e4fb53
LB		 6350 * if our em maps to
6351 * - a hole or
6352 * - a pre-alloc extent,
6353 * there might actually be delalloc bytes behind it.
ec29ed5b 6354 */
f9e4fb53
LB		 6355 if (em->block_start != EXTENT_MAP_HOLE &&
6356 !test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
ec29ed5b
CM		 6357 return em;
6358 else
6359 hole_em = em;
6360 }
6361
6362 /* check to see if we've wrapped (len == -1 or similar) */
6363 end = start + len;
6364 if (end < start)
6365 end = (u64)-1;
6366 else
6367 end -= 1;
6368
6369 em = NULL;
6370
6371 /* ok, we didn't find anything, lets look for delalloc */
6372 found = count_range_bits(&BTRFS_I(inode)->io_tree, &range_start,
6373 end, len, EXTENT_DELALLOC, 1);
6374 found_end = range_start + found;
6375 if (found_end < range_start)
6376 found_end = (u64)-1;
6377
6378 /*
6379 * we didn't find anything useful, return
6380 * the original results from get_extent()
6381 */
6382 if (range_start > end || found_end <= start) {
6383 em = hole_em;
6384 hole_em = NULL;
6385 goto out;
6386 }
6387
6388 /* adjust the range_start to make sure it doesn't
6389 * go backwards from the start they passed in
6390 */
6391 range_start = max(start,range_start);
6392 found = found_end - range_start;
6393
6394 if (found > 0) {
6395 u64 hole_start = start;
6396 u64 hole_len = len;
6397
172ddd60 6398 em = alloc_extent_map();
ec29ed5b
CM		 6399 if (!em) {
6400 err = -ENOMEM;
6401 goto out;
6402 }
6403 /*
6404 * when btrfs_get_extent can't find anything it
6405 * returns one huge hole
6406 *
6407 * make sure what it found really fits our range, and
6408 * adjust to make sure it is based on the start from
6409 * the caller
6410 */
6411 if (hole_em) {
6412 u64 calc_end = extent_map_end(hole_em);
6413
6414 if (calc_end <= start || (hole_em->start > end)) {
6415 free_extent_map(hole_em);
6416 hole_em = NULL;
6417 } else {
6418 hole_start = max(hole_em->start, start);
6419 hole_len = calc_end - hole_start;
6420 }
6421 }
6422 em->bdev = NULL;
6423 if (hole_em && range_start > hole_start) {
6424 /* our hole starts before our delalloc, so we
6425 * have to return just the parts of the hole
6426 * that go until the delalloc starts
6427 */
6428 em->len = min(hole_len,
6429 range_start - hole_start);
6430 em->start = hole_start;
6431 em->orig_start = hole_start;
6432 /*
6433 * don't adjust block start at all,
6434 * it is fixed at EXTENT_MAP_HOLE
6435 */
6436 em->block_start = hole_em->block_start;
6437 em->block_len = hole_len;
f9e4fb53
LB		 6438 if (test_bit(EXTENT_FLAG_PREALLOC, &hole_em->flags))
6439 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
ec29ed5b
CM		 6440 } else {
6441 em->start = range_start;
6442 em->len = found;
6443 em->orig_start = range_start;
6444 em->block_start = EXTENT_MAP_DELALLOC;
6445 em->block_len = found;
6446 }
6447 } else if (hole_em) {
6448 return hole_em;
6449 }
6450out:
6451
6452 free_extent_map(hole_em);
6453 if (err) {
6454 free_extent_map(em);
6455 return ERR_PTR(err);
6456 }
6457 return em;
6458}
6459
4b46fce2
JB		 6460static struct extent_map *btrfs_new_extent_direct(struct inode *inode,
6461 u64 start, u64 len)
6462{
6463 struct btrfs_root *root = BTRFS_I(inode)->root;
6464 struct btrfs_trans_handle *trans;
70c8a91c 6465 struct extent_map *em;
4b46fce2
JB		 6466 struct btrfs_key ins;
6467 u64 alloc_hint;
6468 int ret;
4b46fce2 6469
7a7eaa40 6470 trans = btrfs_join_transaction(root);
3612b495
TI		 6471 if (IS_ERR(trans))
6472 return ERR_CAST(trans);
4b46fce2
JB		 6473
6474 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
6475
6476 alloc_hint = get_extent_allocation_hint(inode, start, len);
6477 ret = btrfs_reserve_extent(trans, root, len, root->sectorsize, 0,
81c9ad23 6478 alloc_hint, &ins, 1);
4b46fce2
JB		 6479 if (ret) {
6480 em = ERR_PTR(ret);
6481 goto out;
6482 }
6483
70c8a91c
JB		 6484 em = create_pinned_em(inode, start, ins.offset, start, ins.objectid,
6485 ins.offset, ins.offset, 0);
6486 if (IS_ERR(em))
6487 goto out;
4b46fce2
JB		 6488
6489 ret = btrfs_add_ordered_extent_dio(inode, start, ins.objectid,
6490 ins.offset, ins.offset, 0);
6491 if (ret) {
6492 btrfs_free_reserved_extent(root, ins.objectid, ins.offset);
6493 em = ERR_PTR(ret);
6494 }
6495out:
6496 btrfs_end_transaction(trans, root);
6497 return em;
6498}
6499
46bfbb5c
CM		 6500/*
6501 * returns 1 when the nocow is safe, < 1 on error, 0 if the
6502 * block must be cow'd
6503 */
6504static noinline int can_nocow_odirect(struct btrfs_trans_handle *trans,
6505 struct inode *inode, u64 offset, u64 len)
6506{
6507 struct btrfs_path *path;
6508 int ret;
6509 struct extent_buffer *leaf;
6510 struct btrfs_root *root = BTRFS_I(inode)->root;
6511 struct btrfs_file_extent_item *fi;
6512 struct btrfs_key key;
6513 u64 disk_bytenr;
6514 u64 backref_offset;
6515 u64 extent_end;
6516 u64 num_bytes;
6517 int slot;
6518 int found_type;
6519
6520 path = btrfs_alloc_path();
6521 if (!path)
6522 return -ENOMEM;
6523
33345d01 6524 ret = btrfs_lookup_file_extent(trans, root, path, btrfs_ino(inode),
46bfbb5c
CM		 6525 offset, 0);
6526 if (ret < 0)
6527 goto out;
6528
6529 slot = path->slots[0];
6530 if (ret == 1) {
6531 if (slot == 0) {
6532 /* can't find the item, must cow */
6533 ret = 0;
6534 goto out;
6535 }
6536 slot--;
6537 }
6538 ret = 0;
6539 leaf = path->nodes[0];
6540 btrfs_item_key_to_cpu(leaf, &key, slot);
33345d01 6541 if (key.objectid != btrfs_ino(inode) ||
46bfbb5c
CM		 6542 key.type != BTRFS_EXTENT_DATA_KEY) {
6543 /* not our file or wrong item type, must cow */
6544 goto out;
6545 }
6546
6547 if (key.offset > offset) {
6548 /* Wrong offset, must cow */
6549 goto out;
6550 }
6551
6552 fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
6553 found_type = btrfs_file_extent_type(leaf, fi);
6554 if (found_type != BTRFS_FILE_EXTENT_REG &&
6555 found_type != BTRFS_FILE_EXTENT_PREALLOC) {
6556 /* not a regular extent, must cow */
6557 goto out;
6558 }
6559 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
6560 backref_offset = btrfs_file_extent_offset(leaf, fi);
6561
6562 extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi);
6563 if (extent_end < offset + len) {
6564 /* extent doesn't include our full range, must cow */
6565 goto out;
6566 }
6567
6568 if (btrfs_extent_readonly(root, disk_bytenr))
6569 goto out;
6570
6571 /*
6572 * look for other files referencing this extent, if we
6573 * find any we must cow
6574 */
33345d01 6575 if (btrfs_cross_ref_exist(trans, root, btrfs_ino(inode),
46bfbb5c
CM		 6576 key.offset - backref_offset, disk_bytenr))
6577 goto out;
6578
6579 /*
6580 * adjust disk_bytenr and num_bytes to cover just the bytes
6581 * in this extent we are about to write. If there
6582 * are any csums in that range we have to cow in order
6583 * to keep the csums correct
6584 */
6585 disk_bytenr += backref_offset;
6586 disk_bytenr += offset - key.offset;
6587 num_bytes = min(offset + len, extent_end) - offset;
6588 if (csum_exist_in_range(root, disk_bytenr, num_bytes))
6589 goto out;
6590 /*
6591 * all of the above have passed, it is safe to overwrite this extent
6592 * without cow
6593 */
6594 ret = 1;
6595out:
6596 btrfs_free_path(path);
6597 return ret;
6598}
6599
eb838e73
JB		 6600static int lock_extent_direct(struct inode *inode, u64 lockstart, u64 lockend,
6601 struct extent_state **cached_state, int writing)
6602{
6603 struct btrfs_ordered_extent *ordered;
6604 int ret = 0;
6605
6606 while (1) {
6607 lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend,
6608 0, cached_state);
6609 /*
6610 * We're concerned with the entire range that we're going to be
6611 * doing DIO to, so we need to make sure theres no ordered
6612 * extents in this range.
6613 */
6614 ordered = btrfs_lookup_ordered_range(inode, lockstart,
6615 lockend - lockstart + 1);
6616
6617 /*
6618 * We need to make sure there are no buffered pages in this
6619 * range either, we could have raced between the invalidate in
6620 * generic_file_direct_write and locking the extent. The
6621 * invalidate needs to happen so that reads after a write do not
6622 * get stale data.
6623 */
6624 if (!ordered && (!writing ||
6625 !test_range_bit(&BTRFS_I(inode)->io_tree,
6626 lockstart, lockend, EXTENT_UPTODATE, 0,
6627 *cached_state)))
6628 break;
6629
6630 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend,
6631 cached_state, GFP_NOFS);
6632
6633 if (ordered) {
6634 btrfs_start_ordered_extent(inode, ordered, 1);
6635 btrfs_put_ordered_extent(ordered);
6636 } else {
6637 /* Screw you mmap */
6638 ret = filemap_write_and_wait_range(inode->i_mapping,
6639 lockstart,
6640 lockend);
6641 if (ret)
6642 break;
6643
6644 /*
6645 * If we found a page that couldn't be invalidated just
6646 * fall back to buffered.
6647 */
6648 ret = invalidate_inode_pages2_range(inode->i_mapping,
6649 lockstart >> PAGE_CACHE_SHIFT,
6650 lockend >> PAGE_CACHE_SHIFT);
6651 if (ret)
6652 break;
6653 }
6654
6655 cond_resched();
6656 }
6657
6658 return ret;
6659}
6660
69ffb543
JB		 6661static struct extent_map *create_pinned_em(struct inode *inode, u64 start,
6662 u64 len, u64 orig_start,
6663 u64 block_start, u64 block_len,
b4939680 6664 u64 orig_block_len, int type)
69ffb543
JB		 6665{
6666 struct extent_map_tree *em_tree;
6667 struct extent_map *em;
6668 struct btrfs_root *root = BTRFS_I(inode)->root;
6669 int ret;
6670
6671 em_tree = &BTRFS_I(inode)->extent_tree;
6672 em = alloc_extent_map();
6673 if (!em)
6674 return ERR_PTR(-ENOMEM);
6675
6676 em->start = start;
6677 em->orig_start = orig_start;
2ab28f32
JB		 6678 em->mod_start = start;
6679 em->mod_len = len;
69ffb543
JB		 6680 em->len = len;
6681 em->block_len = block_len;
6682 em->block_start = block_start;
6683 em->bdev = root->fs_info->fs_devices->latest_bdev;
b4939680 6684 em->orig_block_len = orig_block_len;
70c8a91c 6685 em->generation = -1;
69ffb543
JB		 6686 set_bit(EXTENT_FLAG_PINNED, &em->flags);
6687 if (type == BTRFS_ORDERED_PREALLOC)
b11e234d 6688 set_bit(EXTENT_FLAG_FILLING, &em->flags);
69ffb543
JB		 6689
6690 do {
6691 btrfs_drop_extent_cache(inode, em->start,
6692 em->start + em->len - 1, 0);
6693 write_lock(&em_tree->lock);
6694 ret = add_extent_mapping(em_tree, em);
70c8a91c
JB		 6695 if (!ret)
6696 list_move(&em->list,
6697 &em_tree->modified_extents);
69ffb543
JB		 6698 write_unlock(&em_tree->lock);
6699 } while (ret == -EEXIST);
6700
6701 if (ret) {
6702 free_extent_map(em);
6703 return ERR_PTR(ret);
6704 }
6705
6706 return em;
6707}
6708
6709
4b46fce2
JB		 6710static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock,
6711 struct buffer_head *bh_result, int create)
6712{
6713 struct extent_map *em;
6714 struct btrfs_root *root = BTRFS_I(inode)->root;
eb838e73 6715 struct extent_state *cached_state = NULL;
4b46fce2 6716 u64 start = iblock << inode->i_blkbits;
eb838e73 6717 u64 lockstart, lockend;
4b46fce2 6718 u64 len = bh_result->b_size;
46bfbb5c 6719 struct btrfs_trans_handle *trans;
eb838e73 6720 int unlock_bits = EXTENT_LOCKED;
0934856d 6721 int ret = 0;
eb838e73 6722
172a5049 6723 if (create)
eb838e73 6724 unlock_bits |= EXTENT_DELALLOC | EXTENT_DIRTY;
172a5049 6725 else
c329861d 6726 len = min_t(u64, len, root->sectorsize);
eb838e73 6727
c329861d
JB		 6728 lockstart = start;
6729 lockend = start + len - 1;
6730
eb838e73
JB		 6731 /*
6732 * If this errors out it's because we couldn't invalidate pagecache for
6733 * this range and we need to fallback to buffered.
6734 */
6735 if (lock_extent_direct(inode, lockstart, lockend, &cached_state, create))
6736 return -ENOTBLK;
6737
4b46fce2 6738 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
eb838e73
JB		 6739 if (IS_ERR(em)) {
6740 ret = PTR_ERR(em);
6741 goto unlock_err;
6742 }
4b46fce2
JB		 6743
6744 /*
6745 * Ok for INLINE and COMPRESSED extents we need to fallback on buffered
6746 * io. INLINE is special, and we could probably kludge it in here, but
6747 * it's still buffered so for safety lets just fall back to the generic
6748 * buffered path.
6749 *
6750 * For COMPRESSED we _have_ to read the entire extent in so we can
6751 * decompress it, so there will be buffering required no matter what we
6752 * do, so go ahead and fallback to buffered.
6753 *
6754 * We return -ENOTBLK because thats what makes DIO go ahead and go back
6755 * to buffered IO. Don't blame me, this is the price we pay for using
6756 * the generic code.
6757 */
6758 if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags) ||
6759 em->block_start == EXTENT_MAP_INLINE) {
6760 free_extent_map(em);
eb838e73
JB		 6761 ret = -ENOTBLK;
6762 goto unlock_err;
4b46fce2
JB		 6763 }
6764
6765 /* Just a good old fashioned hole, return */
6766 if (!create && (em->block_start == EXTENT_MAP_HOLE ||
6767 test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) {
6768 free_extent_map(em);
eb838e73 6769 goto unlock_err;
4b46fce2
JB		 6770 }
6771
6772 /*
6773 * We don't allocate a new extent in the following cases
6774 *
6775 * 1) The inode is marked as NODATACOW. In this case we'll just use the
6776 * existing extent.
6777 * 2) The extent is marked as PREALLOC. We're good to go here and can
6778 * just use the extent.
6779 *
6780 */
46bfbb5c 6781 if (!create) {
eb838e73
JB		 6782 len = min(len, em->len - (start - em->start));
6783 lockstart = start + len;
6784 goto unlock;
46bfbb5c 6785 }
4b46fce2
JB		 6786
6787 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags) ||
6788 ((BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) &&
6789 em->block_start != EXTENT_MAP_HOLE)) {
4b46fce2
JB		 6790 int type;
6791 int ret;
46bfbb5c 6792 u64 block_start;
4b46fce2
JB		 6793
6794 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
6795 type = BTRFS_ORDERED_PREALLOC;
6796 else
6797 type = BTRFS_ORDERED_NOCOW;
46bfbb5c 6798 len = min(len, em->len - (start - em->start));
4b46fce2 6799 block_start = em->block_start + (start - em->start);
46bfbb5c
CM		 6800
6801 /*
6802 * we're not going to log anything, but we do need
6803 * to make sure the current transaction stays open
6804 * while we look for nocow cross refs
6805 */
7a7eaa40 6806 trans = btrfs_join_transaction(root);
3612b495 6807 if (IS_ERR(trans))
46bfbb5c
CM		 6808 goto must_cow;
6809
6810 if (can_nocow_odirect(trans, inode, start, len) == 1) {
70c8a91c 6811 u64 orig_start = em->orig_start;
b4939680 6812 u64 orig_block_len = em->orig_block_len;
69ffb543
JB		 6813
6814 if (type == BTRFS_ORDERED_PREALLOC) {
6815 free_extent_map(em);
6816 em = create_pinned_em(inode, start, len,
6817 orig_start,
b4939680
JB		 6818 block_start, len,
6819 orig_block_len, type);
69ffb543
JB		 6820 if (IS_ERR(em)) {
6821 btrfs_end_transaction(trans, root);
6822 goto unlock_err;
6823 }
6824 }
6825
46bfbb5c
CM		 6826 ret = btrfs_add_ordered_extent_dio(inode, start,
6827 block_start, len, len, type);
6828 btrfs_end_transaction(trans, root);
6829 if (ret) {
6830 free_extent_map(em);
eb838e73 6831 goto unlock_err;
46bfbb5c
CM		 6832 }
6833 goto unlock;
4b46fce2 6834 }
46bfbb5c 6835 btrfs_end_transaction(trans, root);
4b46fce2 6836 }
46bfbb5c
CM		 6837must_cow:
6838 /*
6839 * this will cow the extent, reset the len in case we changed
6840 * it above
6841 */
6842 len = bh_result->b_size;
70c8a91c
JB		 6843 free_extent_map(em);
6844 em = btrfs_new_extent_direct(inode, start, len);
eb838e73
JB		 6845 if (IS_ERR(em)) {
6846 ret = PTR_ERR(em);
6847 goto unlock_err;
6848 }
46bfbb5c
CM		 6849 len = min(len, em->len - (start - em->start));
6850unlock:
4b46fce2
JB		 6851 bh_result->b_blocknr = (em->block_start + (start - em->start)) >>
6852 inode->i_blkbits;
46bfbb5c 6853 bh_result->b_size = len;
4b46fce2
JB		 6854 bh_result->b_bdev = em->bdev;
6855 set_buffer_mapped(bh_result);
c3473e83
JB		 6856 if (create) {
6857 if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
6858 set_buffer_new(bh_result);
6859
6860 /*
6861 * Need to update the i_size under the extent lock so buffered
6862 * readers will get the updated i_size when we unlock.
6863 */
6864 if (start + len > i_size_read(inode))
6865 i_size_write(inode, start + len);
0934856d 6866
172a5049
MX		 6867 spin_lock(&BTRFS_I(inode)->lock);
6868 BTRFS_I(inode)->outstanding_extents++;
6869 spin_unlock(&BTRFS_I(inode)->lock);
6870
0934856d
MX		 6871 ret = set_extent_bit(&BTRFS_I(inode)->io_tree, lockstart,
6872 lockstart + len - 1, EXTENT_DELALLOC, NULL,
6873 &cached_state, GFP_NOFS);
6874 BUG_ON(ret);
c3473e83 6875 }
4b46fce2 6876
eb838e73
JB		 6877 /*
6878 * In the case of write we need to clear and unlock the entire range,
6879 * in the case of read we need to unlock only the end area that we
6880 * aren't using if there is any left over space.
6881 */
24c03fa5 6882 if (lockstart < lockend) {
0934856d
MX		 6883 clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart,
6884 lockend, unlock_bits, 1, 0,
6885 &cached_state, GFP_NOFS);
24c03fa5 6886 } else {
eb838e73 6887 free_extent_state(cached_state);
24c03fa5 6888 }
eb838e73 6889
4b46fce2
JB		 6890 free_extent_map(em);
6891
6892 return 0;
eb838e73
JB		 6893
6894unlock_err:
eb838e73
JB		 6895 clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend,
6896 unlock_bits, 1, 0, &cached_state, GFP_NOFS);
6897 return ret;
4b46fce2
JB		 6898}
6899
6900struct btrfs_dio_private {
6901 struct inode *inode;
6902 u64 logical_offset;
6903 u64 disk_bytenr;
6904 u64 bytes;
4b46fce2 6905 void *private;
e65e1535
MX		 6906
6907 /* number of bios pending for this dio */
6908 atomic_t pending_bios;
6909
6910 /* IO errors */
6911 int errors;
6912
6913 struct bio *orig_bio;
4b46fce2
JB		 6914};
6915
6916static void btrfs_endio_direct_read(struct bio *bio, int err)
6917{
e65e1535 6918 struct btrfs_dio_private *dip = bio->bi_private;
4b46fce2
JB		 6919 struct bio_vec *bvec_end = bio->bi_io_vec + bio->bi_vcnt - 1;
6920 struct bio_vec *bvec = bio->bi_io_vec;
4b46fce2 6921 struct inode *inode = dip->inode;
4b46fce2 6922 u64 start;
4b46fce2
JB		 6923
6924 start = dip->logical_offset;
6925 do {
6926 if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) {
6927 struct page *page = bvec->bv_page;
6928 char *kaddr;
6929 u32 csum = ~(u32)0;
c329861d 6930 u64 private = ~(u32)0;
4b46fce2
JB		 6931 unsigned long flags;
6932
c329861d
JB		 6933 if (get_state_private(&BTRFS_I(inode)->io_tree,
6934 start, &private))
6935 goto failed;
4b46fce2 6936 local_irq_save(flags);
7ac687d9 6937 kaddr = kmap_atomic(page);
b0496686 6938 csum = btrfs_csum_data(kaddr + bvec->bv_offset,
4b46fce2
JB		 6939 csum, bvec->bv_len);
6940 btrfs_csum_final(csum, (char *)&csum);
7ac687d9 6941 kunmap_atomic(kaddr);
4b46fce2
JB		 6942 local_irq_restore(flags);
6943
6944 flush_dcache_page(bvec->bv_page);
c329861d
JB		 6945 if (csum != private) {
6946failed:
33345d01 6947 printk(KERN_ERR "btrfs csum failed ino %llu off"
4b46fce2 6948 " %llu csum %u private %u\n",
33345d01
LZ		 6949 (unsigned long long)btrfs_ino(inode),
6950 (unsigned long long)start,
c329861d 6951 csum, (unsigned)private);
4b46fce2
JB		 6952 err = -EIO;
6953 }
6954 }
6955
6956 start += bvec->bv_len;
4b46fce2
JB		 6957 bvec++;
6958 } while (bvec <= bvec_end);
6959
6960 unlock_extent(&BTRFS_I(inode)->io_tree, dip->logical_offset,
d0082371 6961 dip->logical_offset + dip->bytes - 1);
4b46fce2
JB		 6962 bio->bi_private = dip->private;
6963
4b46fce2 6964 kfree(dip);
c0da7aa1
JB		 6965
6966 /* If we had a csum failure make sure to clear the uptodate flag */
6967 if (err)
6968 clear_bit(BIO_UPTODATE, &bio->bi_flags);
4b46fce2
JB		 6969 dio_end_io(bio, err);
6970}
6971
6972static void btrfs_endio_direct_write(struct bio *bio, int err)
6973{
6974 struct btrfs_dio_private *dip = bio->bi_private;
6975 struct inode *inode = dip->inode;
6976 struct btrfs_root *root = BTRFS_I(inode)->root;
4b46fce2 6977 struct btrfs_ordered_extent *ordered = NULL;
163cf09c
CM		 6978 u64 ordered_offset = dip->logical_offset;
6979 u64 ordered_bytes = dip->bytes;
4b46fce2
JB		 6980 int ret;
6981
6982 if (err)
6983 goto out_done;
163cf09c
CM		 6984again:
6985 ret = btrfs_dec_test_first_ordered_pending(inode, &ordered,
6986 &ordered_offset,
5fd02043 6987 ordered_bytes, !err);
4b46fce2 6988 if (!ret)
163cf09c 6989 goto out_test;
4b46fce2 6990
5fd02043
JB		 6991 ordered->work.func = finish_ordered_fn;
6992 ordered->work.flags = 0;
6993 btrfs_queue_worker(&root->fs_info->endio_write_workers,
6994 &ordered->work);
163cf09c
CM		 6995out_test:
6996 /*
6997 * our bio might span multiple ordered extents. If we haven't
6998 * completed the accounting for the whole dio, go back and try again
6999 */
7000 if (ordered_offset < dip->logical_offset + dip->bytes) {
7001 ordered_bytes = dip->logical_offset + dip->bytes -
7002 ordered_offset;
5fd02043 7003 ordered = NULL;
163cf09c
CM		 7004 goto again;
7005 }
4b46fce2
JB		 7006out_done:
7007 bio->bi_private = dip->private;
7008
4b46fce2 7009 kfree(dip);
c0da7aa1
JB		 7010
7011 /* If we had an error make sure to clear the uptodate flag */
7012 if (err)
7013 clear_bit(BIO_UPTODATE, &bio->bi_flags);
4b46fce2
JB		 7014 dio_end_io(bio, err);
7015}
7016
eaf25d93
CM		 7017static int __btrfs_submit_bio_start_direct_io(struct inode *inode, int rw,
7018 struct bio *bio, int mirror_num,
7019 unsigned long bio_flags, u64 offset)
7020{
7021 int ret;
7022 struct btrfs_root *root = BTRFS_I(inode)->root;
7023 ret = btrfs_csum_one_bio(root, inode, bio, offset, 1);
79787eaa 7024 BUG_ON(ret); /* -ENOMEM */
eaf25d93
CM		 7025 return 0;
7026}
7027
e65e1535
MX		 7028static void btrfs_end_dio_bio(struct bio *bio, int err)
7029{
7030 struct btrfs_dio_private *dip = bio->bi_private;
7031
7032 if (err) {
33345d01 7033 printk(KERN_ERR "btrfs direct IO failed ino %llu rw %lu "
3dd1462e 7034 "sector %#Lx len %u err no %d\n",
33345d01 7035 (unsigned long long)btrfs_ino(dip->inode), bio->bi_rw,
3dd1462e 7036 (unsigned long long)bio->bi_sector, bio->bi_size, err);
e65e1535
MX		 7037 dip->errors = 1;
7038
7039 /*
7040 * before atomic variable goto zero, we must make sure
7041 * dip->errors is perceived to be set.
7042 */
7043 smp_mb__before_atomic_dec();
7044 }
7045
7046 /* if there are more bios still pending for this dio, just exit */
7047 if (!atomic_dec_and_test(&dip->pending_bios))
7048 goto out;
7049
7050 if (dip->errors)
7051 bio_io_error(dip->orig_bio);
7052 else {
7053 set_bit(BIO_UPTODATE, &dip->orig_bio->bi_flags);
7054 bio_endio(dip->orig_bio, 0);
7055 }
7056out:
7057 bio_put(bio);
7058}
7059
7060static struct bio *btrfs_dio_bio_alloc(struct block_device *bdev,
7061 u64 first_sector, gfp_t gfp_flags)
7062{
7063 int nr_vecs = bio_get_nr_vecs(bdev);
7064 return btrfs_bio_alloc(bdev, first_sector, nr_vecs, gfp_flags);
7065}
7066
7067static inline int __btrfs_submit_dio_bio(struct bio *bio, struct inode *inode,
7068 int rw, u64 file_offset, int skip_sum,
c329861d 7069 int async_submit)
e65e1535
MX		 7070{
7071 int write = rw & REQ_WRITE;
7072 struct btrfs_root *root = BTRFS_I(inode)->root;
7073 int ret;
7074
b812ce28
JB		 7075 if (async_submit)
7076 async_submit = !atomic_read(&BTRFS_I(inode)->sync_writers);
7077
e65e1535 7078 bio_get(bio);
5fd02043
JB		 7079
7080 if (!write) {
7081 ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
7082 if (ret)
7083 goto err;
7084 }
e65e1535 7085
1ae39938
JB		 7086 if (skip_sum)
7087 goto map;
7088
7089 if (write && async_submit) {
e65e1535
MX		 7090 ret = btrfs_wq_submit_bio(root->fs_info,
7091 inode, rw, bio, 0, 0,
7092 file_offset,
7093 __btrfs_submit_bio_start_direct_io,
7094 __btrfs_submit_bio_done);
7095 goto err;
1ae39938
JB		 7096 } else if (write) {
7097 /*
7098 * If we aren't doing async submit, calculate the csum of the
7099 * bio now.
7100 */
7101 ret = btrfs_csum_one_bio(root, inode, bio, file_offset, 1);
7102 if (ret)
7103 goto err;
c2db1073 7104 } else if (!skip_sum) {
c329861d 7105 ret = btrfs_lookup_bio_sums_dio(root, inode, bio, file_offset);
c2db1073
TI		 7106 if (ret)
7107 goto err;
7108 }
e65e1535 7109
1ae39938
JB		 7110map:
7111 ret = btrfs_map_bio(root, rw, bio, 0, async_submit);
e65e1535
MX		 7112err:
7113 bio_put(bio);
7114 return ret;
7115}
7116
7117static int btrfs_submit_direct_hook(int rw, struct btrfs_dio_private *dip,
7118 int skip_sum)
7119{
7120 struct inode *inode = dip->inode;
7121 struct btrfs_root *root = BTRFS_I(inode)->root;
e65e1535
MX		 7122 struct bio *bio;
7123 struct bio *orig_bio = dip->orig_bio;
7124 struct bio_vec *bvec = orig_bio->bi_io_vec;
7125 u64 start_sector = orig_bio->bi_sector;
7126 u64 file_offset = dip->logical_offset;
7127 u64 submit_len = 0;
7128 u64 map_length;
7129 int nr_pages = 0;
e65e1535 7130 int ret = 0;
1ae39938 7131 int async_submit = 0;
e65e1535 7132
e65e1535 7133 map_length = orig_bio->bi_size;
53b381b3 7134 ret = btrfs_map_block(root->fs_info, rw, start_sector << 9,
e65e1535
MX		 7135 &map_length, NULL, 0);
7136 if (ret) {
64728bbb 7137 bio_put(orig_bio);
e65e1535
MX		 7138 return -EIO;
7139 }
02f57c7a
JB		 7140 if (map_length >= orig_bio->bi_size) {
7141 bio = orig_bio;
7142 goto submit;
7143 }
7144
53b381b3
DW		 7145 /* async crcs make it difficult to collect full stripe writes. */
7146 if (btrfs_get_alloc_profile(root, 1) &
7147 (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6))
7148 async_submit = 0;
7149 else
7150 async_submit = 1;
7151
02f57c7a
JB		 7152 bio = btrfs_dio_bio_alloc(orig_bio->bi_bdev, start_sector, GFP_NOFS);
7153 if (!bio)
7154 return -ENOMEM;
7155 bio->bi_private = dip;
7156 bio->bi_end_io = btrfs_end_dio_bio;
7157 atomic_inc(&dip->pending_bios);
7158
e65e1535
MX		 7159 while (bvec <= (orig_bio->bi_io_vec + orig_bio->bi_vcnt - 1)) {
7160 if (unlikely(map_length < submit_len + bvec->bv_len ||
7161 bio_add_page(bio, bvec->bv_page, bvec->bv_len,
7162 bvec->bv_offset) < bvec->bv_len)) {
7163 /*
7164 * inc the count before we submit the bio so
7165 * we know the end IO handler won't happen before
7166 * we inc the count. Otherwise, the dip might get freed
7167 * before we're done setting it up
7168 */
7169 atomic_inc(&dip->pending_bios);
7170 ret = __btrfs_submit_dio_bio(bio, inode, rw,
7171 file_offset, skip_sum,
c329861d 7172 async_submit);
e65e1535
MX		 7173 if (ret) {
7174 bio_put(bio);
7175 atomic_dec(&dip->pending_bios);
7176 goto out_err;
7177 }
7178
e65e1535
MX		 7179 start_sector += submit_len >> 9;
7180 file_offset += submit_len;
7181
7182 submit_len = 0;
7183 nr_pages = 0;
7184
7185 bio = btrfs_dio_bio_alloc(orig_bio->bi_bdev,
7186 start_sector, GFP_NOFS);
7187 if (!bio)
7188 goto out_err;
7189 bio->bi_private = dip;
7190 bio->bi_end_io = btrfs_end_dio_bio;
7191
7192 map_length = orig_bio->bi_size;
53b381b3 7193 ret = btrfs_map_block(root->fs_info, rw,
3ec706c8 7194 start_sector << 9,
e65e1535
MX		 7195 &map_length, NULL, 0);
7196 if (ret) {
7197 bio_put(bio);
7198 goto out_err;
7199 }
7200 } else {
7201 submit_len += bvec->bv_len;
7202 nr_pages ++;
7203 bvec++;
7204 }
7205 }
7206
02f57c7a 7207submit:
e65e1535 7208 ret = __btrfs_submit_dio_bio(bio, inode, rw, file_offset, skip_sum,
c329861d 7209 async_submit);
e65e1535
MX		 7210 if (!ret)
7211 return 0;
7212
7213 bio_put(bio);
7214out_err:
7215 dip->errors = 1;
7216 /*
7217 * before atomic variable goto zero, we must
7218 * make sure dip->errors is perceived to be set.
7219 */
7220 smp_mb__before_atomic_dec();
7221 if (atomic_dec_and_test(&dip->pending_bios))
7222 bio_io_error(dip->orig_bio);
7223
7224 /* bio_end_io() will handle error, so we needn't return it */
7225 return 0;
7226}
7227
4b46fce2
JB		 7228static void btrfs_submit_direct(int rw, struct bio *bio, struct inode *inode,
7229 loff_t file_offset)
7230{
7231 struct btrfs_root *root = BTRFS_I(inode)->root;
7232 struct btrfs_dio_private *dip;
7233 struct bio_vec *bvec = bio->bi_io_vec;
4b46fce2 7234 int skip_sum;
7b6d91da 7235 int write = rw & REQ_WRITE;
4b46fce2
JB		 7236 int ret = 0;
7237
7238 skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
7239
7240 dip = kmalloc(sizeof(*dip), GFP_NOFS);
7241 if (!dip) {
7242 ret = -ENOMEM;
7243 goto free_ordered;
7244 }
4b46fce2
JB		 7245
7246 dip->private = bio->bi_private;
7247 dip->inode = inode;
7248 dip->logical_offset = file_offset;
7249
4b46fce2
JB		 7250 dip->bytes = 0;
7251 do {
7252 dip->bytes += bvec->bv_len;
7253 bvec++;
7254 } while (bvec <= (bio->bi_io_vec + bio->bi_vcnt - 1));
7255
46bfbb5c 7256 dip->disk_bytenr = (u64)bio->bi_sector << 9;
4b46fce2 7257 bio->bi_private = dip;
e65e1535
MX		 7258 dip->errors = 0;
7259 dip->orig_bio = bio;
7260 atomic_set(&dip->pending_bios, 0);
4b46fce2
JB		 7261
7262 if (write)
7263 bio->bi_end_io = btrfs_endio_direct_write;
7264 else
7265 bio->bi_end_io = btrfs_endio_direct_read;
7266
e65e1535
MX		 7267 ret = btrfs_submit_direct_hook(rw, dip, skip_sum);
7268 if (!ret)
eaf25d93 7269 return;
4b46fce2
JB		 7270free_ordered:
7271 /*
7272 * If this is a write, we need to clean up the reserved space and kill
7273 * the ordered extent.
7274 */
7275 if (write) {
7276 struct btrfs_ordered_extent *ordered;
955256f2 7277 ordered = btrfs_lookup_ordered_extent(inode, file_offset);
4b46fce2
JB		 7278 if (!test_bit(BTRFS_ORDERED_PREALLOC, &ordered->flags) &&
7279 !test_bit(BTRFS_ORDERED_NOCOW, &ordered->flags))
7280 btrfs_free_reserved_extent(root, ordered->start,
7281 ordered->disk_len);
7282 btrfs_put_ordered_extent(ordered);
7283 btrfs_put_ordered_extent(ordered);
7284 }
7285 bio_endio(bio, ret);
7286}
7287
5a5f79b5
CM		 7288static ssize_t check_direct_IO(struct btrfs_root *root, int rw, struct kiocb *iocb,
7289 const struct iovec *iov, loff_t offset,
7290 unsigned long nr_segs)
7291{
7292 int seg;
a1b75f7d 7293 int i;
5a5f79b5
CM		 7294 size_t size;
7295 unsigned long addr;
7296 unsigned blocksize_mask = root->sectorsize - 1;
7297 ssize_t retval = -EINVAL;
7298 loff_t end = offset;
7299
7300 if (offset & blocksize_mask)
7301 goto out;
7302
7303 /* Check the memory alignment. Blocks cannot straddle pages */
7304 for (seg = 0; seg < nr_segs; seg++) {
7305 addr = (unsigned long)iov[seg].iov_base;
7306 size = iov[seg].iov_len;
7307 end += size;
a1b75f7d 7308 if ((addr & blocksize_mask) || (size & blocksize_mask))
5a5f79b5 7309 goto out;
a1b75f7d
JB		 7310
7311 /* If this is a write we don't need to check anymore */
7312 if (rw & WRITE)
7313 continue;
7314
7315 /*
7316 * Check to make sure we don't have duplicate iov_base's in this
7317 * iovec, if so return EINVAL, otherwise we'll get csum errors
7318 * when reading back.
7319 */
7320 for (i = seg + 1; i < nr_segs; i++) {
7321 if (iov[seg].iov_base == iov[i].iov_base)
7322 goto out;
7323 }
5a5f79b5
CM		 7324 }
7325 retval = 0;
7326out:
7327 return retval;
7328}
eb838e73 7329
16432985
CM		 7330static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb,
7331 const struct iovec *iov, loff_t offset,
7332 unsigned long nr_segs)
7333{
4b46fce2
JB		 7334 struct file *file = iocb->ki_filp;
7335 struct inode *inode = file->f_mapping->host;
0934856d 7336 size_t count = 0;
2e60a51e 7337 int flags = 0;
38851cc1
MX		 7338 bool wakeup = true;
7339 bool relock = false;
0934856d 7340 ssize_t ret;
4b46fce2 7341
5a5f79b5 7342 if (check_direct_IO(BTRFS_I(inode)->root, rw, iocb, iov,
eb838e73 7343 offset, nr_segs))
5a5f79b5 7344 return 0;
3f7c579c 7345
38851cc1
MX		 7346 atomic_inc(&inode->i_dio_count);
7347 smp_mb__after_atomic_inc();
7348
0934856d
MX		 7349 if (rw & WRITE) {
7350 count = iov_length(iov, nr_segs);
38851cc1
MX		 7351 /*
7352 * If the write DIO is beyond the EOF, we need update
7353 * the isize, but it is protected by i_mutex. So we can
7354 * not unlock the i_mutex at this case.
7355 */
7356 if (offset + count <= inode->i_size) {
7357 mutex_unlock(&inode->i_mutex);
7358 relock = true;
7359 }
0934856d
MX		 7360 ret = btrfs_delalloc_reserve_space(inode, count);
7361 if (ret)
38851cc1
MX		 7362 goto out;
7363 } else if (unlikely(test_bit(BTRFS_INODE_READDIO_NEED_LOCK,
7364 &BTRFS_I(inode)->runtime_flags))) {
7365 inode_dio_done(inode);
7366 flags = DIO_LOCKING | DIO_SKIP_HOLES;
7367 wakeup = false;
0934856d
MX		 7368 }
7369
7370 ret = __blockdev_direct_IO(rw, iocb, inode,
7371 BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev,
7372 iov, offset, nr_segs, btrfs_get_blocks_direct, NULL,
2e60a51e 7373 btrfs_submit_direct, flags);
0934856d
MX		 7374 if (rw & WRITE) {
7375 if (ret < 0 && ret != -EIOCBQUEUED)
7376 btrfs_delalloc_release_space(inode, count);
172a5049 7377 else if (ret >= 0 && (size_t)ret < count)
0934856d
MX		 7378 btrfs_delalloc_release_space(inode,
7379 count - (size_t)ret);
172a5049
MX		 7380 else
7381 btrfs_delalloc_release_metadata(inode, 0);
0934856d 7382 }
38851cc1 7383out:
2e60a51e
MX		 7384 if (wakeup)
7385 inode_dio_done(inode);
38851cc1
MX		 7386 if (relock)
7387 mutex_lock(&inode->i_mutex);
0934856d
MX		 7388
7389 return ret;
16432985
CM		 7390}
7391
05dadc09
TI		 7392#define BTRFS_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC)
7393
1506fcc8
YS		 7394static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
7395 __u64 start, __u64 len)
7396{
05dadc09
TI		 7397 int ret;
7398
7399 ret = fiemap_check_flags(fieinfo, BTRFS_FIEMAP_FLAGS);
7400 if (ret)
7401 return ret;
7402
ec29ed5b 7403 return extent_fiemap(inode, fieinfo, start, len, btrfs_get_extent_fiemap);
1506fcc8
YS		 7404}
7405
a52d9a80 7406int btrfs_readpage(struct file *file, struct page *page)
9ebefb18 7407{
d1310b2e
CM		 7408 struct extent_io_tree *tree;
7409 tree = &BTRFS_I(page->mapping->host)->io_tree;
8ddc7d9c 7410 return extent_read_full_page(tree, page, btrfs_get_extent, 0);
9ebefb18 7411}
1832a6d5 7412
a52d9a80 7413static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
39279cc3 7414{
d1310b2e 7415 struct extent_io_tree *tree;
b888db2b
CM		 7416
7417
7418 if (current->flags & PF_MEMALLOC) {
7419 redirty_page_for_writepage(wbc, page);
7420 unlock_page(page);
7421 return 0;
7422 }
d1310b2e 7423 tree = &BTRFS_I(page->mapping->host)->io_tree;
a52d9a80 7424 return extent_write_full_page(tree, page, btrfs_get_extent, wbc);
9ebefb18
CM		 7425}
7426
f421950f
CM		 7427int btrfs_writepages(struct address_space *mapping,
7428 struct writeback_control *wbc)
b293f02e 7429{
d1310b2e 7430 struct extent_io_tree *tree;
771ed689 7431
d1310b2e 7432 tree = &BTRFS_I(mapping->host)->io_tree;
b293f02e
CM		 7433 return extent_writepages(tree, mapping, btrfs_get_extent, wbc);
7434}
7435
3ab2fb5a
CM		 7436static int
7437btrfs_readpages(struct file *file, struct address_space *mapping,
7438 struct list_head *pages, unsigned nr_pages)
7439{
d1310b2e
CM		 7440 struct extent_io_tree *tree;
7441 tree = &BTRFS_I(mapping->host)->io_tree;
3ab2fb5a
CM		 7442 return extent_readpages(tree, mapping, pages, nr_pages,
7443 btrfs_get_extent);
7444}
e6dcd2dc 7445static int __btrfs_releasepage(struct page *page, gfp_t gfp_flags)
9ebefb18 7446{
d1310b2e
CM		 7447 struct extent_io_tree *tree;
7448 struct extent_map_tree *map;
a52d9a80 7449 int ret;
8c2383c3 7450
d1310b2e
CM		 7451 tree = &BTRFS_I(page->mapping->host)->io_tree;
7452 map = &BTRFS_I(page->mapping->host)->extent_tree;
70dec807 7453 ret = try_release_extent_mapping(map, tree, page, gfp_flags);
a52d9a80
CM		 7454 if (ret == 1) {
7455 ClearPagePrivate(page);
7456 set_page_private(page, 0);
7457 page_cache_release(page);
39279cc3 7458 }
a52d9a80 7459 return ret;
39279cc3
CM		 7460}
7461
e6dcd2dc
CM		 7462static int btrfs_releasepage(struct page *page, gfp_t gfp_flags)
7463{
98509cfc
CM		 7464 if (PageWriteback(page) || PageDirty(page))
7465 return 0;
b335b003 7466 return __btrfs_releasepage(page, gfp_flags & GFP_NOFS);
e6dcd2dc
CM		 7467}
7468
a52d9a80 7469static void btrfs_invalidatepage(struct page *page, unsigned long offset)
39279cc3 7470{
5fd02043 7471 struct inode *inode = page->mapping->host;
d1310b2e 7472 struct extent_io_tree *tree;
e6dcd2dc 7473 struct btrfs_ordered_extent *ordered;
2ac55d41 7474 struct extent_state *cached_state = NULL;
e6dcd2dc
CM		 7475 u64 page_start = page_offset(page);
7476 u64 page_end = page_start + PAGE_CACHE_SIZE - 1;
39279cc3 7477
8b62b72b
CM		 7478 /*
7479 * we have the page locked, so new writeback can't start,
7480 * and the dirty bit won't be cleared while we are here.
7481 *
7482 * Wait for IO on this page so that we can safely clear
7483 * the PagePrivate2 bit and do ordered accounting
7484 */
e6dcd2dc 7485 wait_on_page_writeback(page);
8b62b72b 7486
5fd02043 7487 tree = &BTRFS_I(inode)->io_tree;
e6dcd2dc
CM		 7488 if (offset) {
7489 btrfs_releasepage(page, GFP_NOFS);
7490 return;
7491 }
d0082371 7492 lock_extent_bits(tree, page_start, page_end, 0, &cached_state);
4eee4fa4 7493 ordered = btrfs_lookup_ordered_extent(inode, page_offset(page));
e6dcd2dc 7494 if (ordered) {
eb84ae03
CM		 7495 /*
7496 * IO on this page will never be started, so we need
7497 * to account for any ordered extents now
7498 */
e6dcd2dc
CM		 7499 clear_extent_bit(tree, page_start, page_end,
7500 EXTENT_DIRTY | EXTENT_DELALLOC |
9e8a4a8b
LB		 7501 EXTENT_LOCKED | EXTENT_DO_ACCOUNTING |
7502 EXTENT_DEFRAG, 1, 0, &cached_state, GFP_NOFS);
8b62b72b
CM		 7503 /*
7504 * whoever cleared the private bit is responsible
7505 * for the finish_ordered_io
7506 */
5fd02043
JB		 7507 if (TestClearPagePrivate2(page) &&
7508 btrfs_dec_test_ordered_pending(inode, &ordered, page_start,
7509 PAGE_CACHE_SIZE, 1)) {
7510 btrfs_finish_ordered_io(ordered);
8b62b72b 7511 }
e6dcd2dc 7512 btrfs_put_ordered_extent(ordered);
2ac55d41 7513 cached_state = NULL;
d0082371 7514 lock_extent_bits(tree, page_start, page_end, 0, &cached_state);
e6dcd2dc
CM		 7515 }
7516 clear_extent_bit(tree, page_start, page_end,
32c00aff 7517 EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC |
9e8a4a8b
LB		 7518 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 1, 1,
7519 &cached_state, GFP_NOFS);
e6dcd2dc
CM		 7520 __btrfs_releasepage(page, GFP_NOFS);
7521
4a096752 7522 ClearPageChecked(page);
9ad6b7bc 7523 if (PagePrivate(page)) {
9ad6b7bc
CM		 7524 ClearPagePrivate(page);
7525 set_page_private(page, 0);
7526 page_cache_release(page);
7527 }
39279cc3
CM		 7528}
7529
9ebefb18
CM		 7530/*
7531 * btrfs_page_mkwrite() is not allowed to change the file size as it gets
7532 * called from a page fault handler when a page is first dirtied. Hence we must
7533 * be careful to check for EOF conditions here. We set the page up correctly
7534 * for a written page which means we get ENOSPC checking when writing into
7535 * holes and correct delalloc and unwritten extent mapping on filesystems that
7536 * support these features.
7537 *
7538 * We are not allowed to take the i_mutex here so we have to play games to
7539 * protect against truncate races as the page could now be beyond EOF. Because
7540 * vmtruncate() writes the inode size before removing pages, once we have the
7541 * page lock we can determine safely if the page is beyond EOF. If it is not
7542 * beyond EOF, then the page is guaranteed safe against truncation until we
7543 * unlock the page.
7544 */
c2ec175c 7545int btrfs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
9ebefb18 7546{
c2ec175c 7547 struct page *page = vmf->page;
496ad9aa 7548 struct inode *inode = file_inode(vma->vm_file);
1832a6d5 7549 struct btrfs_root *root = BTRFS_I(inode)->root;
e6dcd2dc
CM		 7550 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
7551 struct btrfs_ordered_extent *ordered;
2ac55d41 7552 struct extent_state *cached_state = NULL;
e6dcd2dc
CM		 7553 char *kaddr;
7554 unsigned long zero_start;
9ebefb18 7555 loff_t size;
1832a6d5 7556 int ret;
9998eb70 7557 int reserved = 0;
a52d9a80 7558 u64 page_start;
e6dcd2dc 7559 u64 page_end;
9ebefb18 7560
b2b5ef5c 7561 sb_start_pagefault(inode->i_sb);
0ca1f7ce 7562 ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
9998eb70 7563 if (!ret) {
e41f941a 7564 ret = file_update_time(vma->vm_file);
9998eb70
CM		 7565 reserved = 1;
7566 }
56a76f82
NP		 7567 if (ret) {
7568 if (ret == -ENOMEM)
7569 ret = VM_FAULT_OOM;
7570 else /* -ENOSPC, -EIO, etc */
7571 ret = VM_FAULT_SIGBUS;
9998eb70
CM		 7572 if (reserved)
7573 goto out;
7574 goto out_noreserve;
56a76f82 7575 }
1832a6d5 7576
56a76f82 7577 ret = VM_FAULT_NOPAGE; /* make the VM retry the fault */
e6dcd2dc 7578again:
9ebefb18 7579 lock_page(page);
9ebefb18 7580 size = i_size_read(inode);
e6dcd2dc
CM		 7581 page_start = page_offset(page);
7582 page_end = page_start + PAGE_CACHE_SIZE - 1;
a52d9a80 7583
9ebefb18 7584 if ((page->mapping != inode->i_mapping) ||
e6dcd2dc 7585 (page_start >= size)) {
9ebefb18
CM		 7586 /* page got truncated out from underneath us */
7587 goto out_unlock;
7588 }
e6dcd2dc
CM		 7589 wait_on_page_writeback(page);
7590
d0082371 7591 lock_extent_bits(io_tree, page_start, page_end, 0, &cached_state);
e6dcd2dc
CM		 7592 set_page_extent_mapped(page);
7593
eb84ae03
CM		 7594 /*
7595 * we can't set the delalloc bits if there are pending ordered
7596 * extents. Drop our locks and wait for them to finish
7597 */
e6dcd2dc
CM		 7598 ordered = btrfs_lookup_ordered_extent(inode, page_start);
7599 if (ordered) {
2ac55d41
JB		 7600 unlock_extent_cached(io_tree, page_start, page_end,
7601 &cached_state, GFP_NOFS);
e6dcd2dc 7602 unlock_page(page);
eb84ae03 7603 btrfs_start_ordered_extent(inode, ordered, 1);
e6dcd2dc
CM		 7604 btrfs_put_ordered_extent(ordered);
7605 goto again;
7606 }
7607
fbf19087
JB		 7608 /*
7609 * XXX - page_mkwrite gets called every time the page is dirtied, even
7610 * if it was already dirty, so for space accounting reasons we need to
7611 * clear any delalloc bits for the range we are fixing to save. There
7612 * is probably a better way to do this, but for now keep consistent with
7613 * prepare_pages in the normal write path.
7614 */
2ac55d41 7615 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, page_end,
9e8a4a8b
LB		 7616 EXTENT_DIRTY | EXTENT_DELALLOC |
7617 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG,
2ac55d41 7618 0, 0, &cached_state, GFP_NOFS);
fbf19087 7619
2ac55d41
JB		 7620 ret = btrfs_set_extent_delalloc(inode, page_start, page_end,
7621 &cached_state);
9ed74f2d 7622 if (ret) {
2ac55d41
JB		 7623 unlock_extent_cached(io_tree, page_start, page_end,
7624 &cached_state, GFP_NOFS);
9ed74f2d
JB		 7625 ret = VM_FAULT_SIGBUS;
7626 goto out_unlock;
7627 }
e6dcd2dc 7628 ret = 0;
9ebefb18
CM		 7629
7630 /* page is wholly or partially inside EOF */
a52d9a80 7631 if (page_start + PAGE_CACHE_SIZE > size)
e6dcd2dc 7632 zero_start = size & ~PAGE_CACHE_MASK;
9ebefb18 7633 else
e6dcd2dc 7634 zero_start = PAGE_CACHE_SIZE;
9ebefb18 7635
e6dcd2dc
CM		 7636 if (zero_start != PAGE_CACHE_SIZE) {
7637 kaddr = kmap(page);
7638 memset(kaddr + zero_start, 0, PAGE_CACHE_SIZE - zero_start);
7639 flush_dcache_page(page);
7640 kunmap(page);
7641 }
247e743c 7642 ClearPageChecked(page);
e6dcd2dc 7643 set_page_dirty(page);
50a9b214 7644 SetPageUptodate(page);
5a3f23d5 7645
257c62e1
CM		 7646 BTRFS_I(inode)->last_trans = root->fs_info->generation;
7647 BTRFS_I(inode)->last_sub_trans = BTRFS_I(inode)->root->log_transid;
46d8bc34 7648 BTRFS_I(inode)->last_log_commit = BTRFS_I(inode)->root->last_log_commit;
257c62e1 7649
2ac55d41 7650 unlock_extent_cached(io_tree, page_start, page_end, &cached_state, GFP_NOFS);
9ebefb18
CM		 7651
7652out_unlock:
b2b5ef5c
JK		 7653 if (!ret) {
7654 sb_end_pagefault(inode->i_sb);
50a9b214 7655 return VM_FAULT_LOCKED;
b2b5ef5c 7656 }
9ebefb18 7657 unlock_page(page);
1832a6d5 7658out:
ec39e180 7659 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
9998eb70 7660out_noreserve:
b2b5ef5c 7661 sb_end_pagefault(inode->i_sb);
9ebefb18
CM		 7662 return ret;
7663}
7664
a41ad394 7665static int btrfs_truncate(struct inode *inode)
39279cc3
CM		 7666{
7667 struct btrfs_root *root = BTRFS_I(inode)->root;
fcb80c2a 7668 struct btrfs_block_rsv *rsv;
39279cc3 7669 int ret;
3893e33b 7670 int err = 0;
39279cc3 7671 struct btrfs_trans_handle *trans;
dbe674a9 7672 u64 mask = root->sectorsize - 1;
07127184 7673 u64 min_size = btrfs_calc_trunc_metadata_size(root, 1);
39279cc3 7674
2aaa6655 7675 ret = btrfs_truncate_page(inode, inode->i_size, 0, 0);
5d5e103a 7676 if (ret)
a41ad394 7677 return ret;
8082510e 7678
4a096752 7679 btrfs_wait_ordered_range(inode, inode->i_size & (~mask), (u64)-1);
8082510e 7680 btrfs_ordered_update_i_size(inode, inode->i_size, NULL);
39279cc3 7681
fcb80c2a
JB		 7682 /*
7683 * Yes ladies and gentelment, this is indeed ugly. The fact is we have
7684 * 3 things going on here
7685 *
7686 * 1) We need to reserve space for our orphan item and the space to
7687 * delete our orphan item. Lord knows we don't want to have a dangling
7688 * orphan item because we didn't reserve space to remove it.
7689 *
7690 * 2) We need to reserve space to update our inode.
7691 *
7692 * 3) We need to have something to cache all the space that is going to
7693 * be free'd up by the truncate operation, but also have some slack
7694 * space reserved in case it uses space during the truncate (thank you
7695 * very much snapshotting).
7696 *
7697 * And we need these to all be seperate. The fact is we can use alot of
7698 * space doing the truncate, and we have no earthly idea how much space
7699 * we will use, so we need the truncate reservation to be seperate so it
7700 * doesn't end up using space reserved for updating the inode or
7701 * removing the orphan item. We also need to be able to stop the
7702 * transaction and start a new one, which means we need to be able to
7703 * update the inode several times, and we have no idea of knowing how
7704 * many times that will be, so we can't just reserve 1 item for the
7705 * entirety of the opration, so that has to be done seperately as well.
7706 * Then there is the orphan item, which does indeed need to be held on
7707 * to for the whole operation, and we need nobody to touch this reserved
7708 * space except the orphan code.
7709 *
7710 * So that leaves us with
7711 *
7712 * 1) root->orphan_block_rsv - for the orphan deletion.
7713 * 2) rsv - for the truncate reservation, which we will steal from the
7714 * transaction reservation.
7715 * 3) fs_info->trans_block_rsv - this will have 1 items worth left for
7716 * updating the inode.
7717 */
66d8f3dd 7718 rsv = btrfs_alloc_block_rsv(root, BTRFS_BLOCK_RSV_TEMP);
fcb80c2a
JB		 7719 if (!rsv)
7720 return -ENOMEM;
4a338542 7721 rsv->size = min_size;
ca7e70f5 7722 rsv->failfast = 1;
f0cd846e 7723
907cbceb 7724 /*
07127184 7725 * 1 for the truncate slack space
907cbceb
JB		 7726 * 1 for updating the inode.
7727 */
f3fe820c 7728 trans = btrfs_start_transaction(root, 2);
fcb80c2a
JB		 7729 if (IS_ERR(trans)) {
7730 err = PTR_ERR(trans);
7731 goto out;
7732 }
f0cd846e 7733
907cbceb
JB		 7734 /* Migrate the slack space for the truncate to our reserve */
7735 ret = btrfs_block_rsv_migrate(&root->fs_info->trans_block_rsv, rsv,
7736 min_size);
fcb80c2a 7737 BUG_ON(ret);
f0cd846e 7738
5a3f23d5
CM		 7739 /*
7740 * setattr is responsible for setting the ordered_data_close flag,
7741 * but that is only tested during the last file release. That
7742 * could happen well after the next commit, leaving a great big
7743 * window where new writes may get lost if someone chooses to write
7744 * to this file after truncating to zero
7745 *
7746 * The inode doesn't have any dirty data here, and so if we commit
7747 * this is a noop. If someone immediately starts writing to the inode
7748 * it is very likely we'll catch some of their writes in this
7749 * transaction, and the commit will find this file on the ordered
7750 * data list with good things to send down.
7751 *
7752 * This is a best effort solution, there is still a window where
7753 * using truncate to replace the contents of the file will
7754 * end up with a zero length file after a crash.
7755 */
72ac3c0d
JB		 7756 if (inode->i_size == 0 && test_bit(BTRFS_INODE_ORDERED_DATA_CLOSE,
7757 &BTRFS_I(inode)->runtime_flags))
5a3f23d5
CM		 7758 btrfs_add_ordered_operation(trans, root, inode);
7759
5dc562c5
JB		 7760 /*
7761 * So if we truncate and then write and fsync we normally would just
7762 * write the extents that changed, which is a problem if we need to
7763 * first truncate that entire inode. So set this flag so we write out
7764 * all of the extents in the inode to the sync log so we're completely
7765 * safe.
7766 */
7767 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags);
ca7e70f5 7768 trans->block_rsv = rsv;
907cbceb 7769
8082510e
YZ		 7770 while (1) {
7771 ret = btrfs_truncate_inode_items(trans, root, inode,
7772 inode->i_size,
7773 BTRFS_EXTENT_DATA_KEY);
ca7e70f5 7774 if (ret != -ENOSPC) {
3893e33b 7775 err = ret;
8082510e 7776 break;
3893e33b 7777 }
39279cc3 7778
fcb80c2a 7779 trans->block_rsv = &root->fs_info->trans_block_rsv;
8082510e 7780 ret = btrfs_update_inode(trans, root, inode);
3893e33b
JB		 7781 if (ret) {
7782 err = ret;
7783 break;
7784 }
ca7e70f5 7785
8082510e 7786 btrfs_end_transaction(trans, root);
b53d3f5d 7787 btrfs_btree_balance_dirty(root);
ca7e70f5
JB		 7788
7789 trans = btrfs_start_transaction(root, 2);
7790 if (IS_ERR(trans)) {
7791 ret = err = PTR_ERR(trans);
7792 trans = NULL;
7793 break;
7794 }
7795
7796 ret = btrfs_block_rsv_migrate(&root->fs_info->trans_block_rsv,
7797 rsv, min_size);
7798 BUG_ON(ret); /* shouldn't happen */
7799 trans->block_rsv = rsv;
8082510e
YZ		 7800 }
7801
7802 if (ret == 0 && inode->i_nlink > 0) {
fcb80c2a 7803 trans->block_rsv = root->orphan_block_rsv;
8082510e 7804 ret = btrfs_orphan_del(trans, inode);
3893e33b
JB		 7805 if (ret)
7806 err = ret;
8082510e
YZ		 7807 }
7808
917c16b2
CM		 7809 if (trans) {
7810 trans->block_rsv = &root->fs_info->trans_block_rsv;
7811 ret = btrfs_update_inode(trans, root, inode);
7812 if (ret && !err)
7813 err = ret;
7b128766 7814
7ad85bb7 7815 ret = btrfs_end_transaction(trans, root);
b53d3f5d 7816 btrfs_btree_balance_dirty(root);
917c16b2 7817 }
fcb80c2a
JB		 7818
7819out:
7820 btrfs_free_block_rsv(root, rsv);
7821
3893e33b
JB		 7822 if (ret && !err)
7823 err = ret;
a41ad394 7824
3893e33b 7825 return err;
39279cc3
CM		 7826}
7827
d352ac68
CM		 7828/*
7829 * create a new subvolume directory/inode (helper for the ioctl).
7830 */
d2fb3437 7831int btrfs_create_subvol_root(struct btrfs_trans_handle *trans,
d82a6f1d 7832 struct btrfs_root *new_root, u64 new_dirid)
39279cc3 7833{
39279cc3 7834 struct inode *inode;
76dda93c 7835 int err;
00e4e6b3 7836 u64 index = 0;
39279cc3 7837
12fc9d09
FA		 7838 inode = btrfs_new_inode(trans, new_root, NULL, "..", 2,
7839 new_dirid, new_dirid,
7840 S_IFDIR | (~current_umask() & S_IRWXUGO),
7841 &index);
54aa1f4d 7842 if (IS_ERR(inode))
f46b5a66 7843 return PTR_ERR(inode);
39279cc3
CM		 7844 inode->i_op = &btrfs_dir_inode_operations;
7845 inode->i_fop = &btrfs_dir_file_operations;
7846
bfe86848 7847 set_nlink(inode, 1);
dbe674a9 7848 btrfs_i_size_write(inode, 0);
3b96362c 7849
76dda93c 7850 err = btrfs_update_inode(trans, new_root, inode);
cb8e7090 7851
76dda93c 7852 iput(inode);
ce598979 7853 return err;
39279cc3
CM		 7854}
7855
39279cc3
CM		 7856struct inode *btrfs_alloc_inode(struct super_block *sb)
7857{
7858 struct btrfs_inode *ei;
2ead6ae7 7859 struct inode *inode;
39279cc3
CM		 7860
7861 ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS);
7862 if (!ei)
7863 return NULL;
2ead6ae7
YZ		 7864
7865 ei->root = NULL;
2ead6ae7 7866 ei->generation = 0;
15ee9bc7 7867 ei->last_trans = 0;
257c62e1 7868 ei->last_sub_trans = 0;
e02119d5 7869 ei->logged_trans = 0;
2ead6ae7 7870 ei->delalloc_bytes = 0;
2ead6ae7
YZ		 7871 ei->disk_i_size = 0;
7872 ei->flags = 0;
7709cde3 7873 ei->csum_bytes = 0;
2ead6ae7
YZ		 7874 ei->index_cnt = (u64)-1;
7875 ei->last_unlink_trans = 0;
46d8bc34 7876 ei->last_log_commit = 0;
2ead6ae7 7877
9e0baf60
JB		 7878 spin_lock_init(&ei->lock);
7879 ei->outstanding_extents = 0;
7880 ei->reserved_extents = 0;
2ead6ae7 7881
72ac3c0d 7882 ei->runtime_flags = 0;
261507a0 7883 ei->force_compress = BTRFS_COMPRESS_NONE;
2ead6ae7 7884
16cdcec7
MX		 7885 ei->delayed_node = NULL;
7886
2ead6ae7 7887 inode = &ei->vfs_inode;
a8067e02 7888 extent_map_tree_init(&ei->extent_tree);
f993c883
DS		 7889 extent_io_tree_init(&ei->io_tree, &inode->i_data);
7890 extent_io_tree_init(&ei->io_failure_tree, &inode->i_data);
0b32f4bb
JB		 7891 ei->io_tree.track_uptodate = 1;
7892 ei->io_failure_tree.track_uptodate = 1;
b812ce28 7893 atomic_set(&ei->sync_writers, 0);
2ead6ae7 7894 mutex_init(&ei->log_mutex);
f248679e 7895 mutex_init(&ei->delalloc_mutex);
e6dcd2dc 7896 btrfs_ordered_inode_tree_init(&ei->ordered_tree);
2ead6ae7 7897 INIT_LIST_HEAD(&ei->delalloc_inodes);
5a3f23d5 7898 INIT_LIST_HEAD(&ei->ordered_operations);
2ead6ae7
YZ		 7899 RB_CLEAR_NODE(&ei->rb_node);
7900
7901 return inode;
39279cc3
CM		 7902}
7903
fa0d7e3d
NP		 7904static void btrfs_i_callback(struct rcu_head *head)
7905{
7906 struct inode *inode = container_of(head, struct inode, i_rcu);
fa0d7e3d
NP		 7907 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
7908}
7909
39279cc3
CM		 7910void btrfs_destroy_inode(struct inode *inode)
7911{
e6dcd2dc 7912 struct btrfs_ordered_extent *ordered;
5a3f23d5
CM		 7913 struct btrfs_root *root = BTRFS_I(inode)->root;
7914
b3d9b7a3 7915 WARN_ON(!hlist_empty(&inode->i_dentry));
39279cc3 7916 WARN_ON(inode->i_data.nrpages);
9e0baf60
JB		 7917 WARN_ON(BTRFS_I(inode)->outstanding_extents);
7918 WARN_ON(BTRFS_I(inode)->reserved_extents);
7709cde3
JB		 7919 WARN_ON(BTRFS_I(inode)->delalloc_bytes);
7920 WARN_ON(BTRFS_I(inode)->csum_bytes);
39279cc3 7921
a6dbd429
JB		 7922 /*
7923 * This can happen where we create an inode, but somebody else also
7924 * created the same inode and we need to destroy the one we already
7925 * created.
7926 */
7927 if (!root)
7928 goto free;
7929
5a3f23d5
CM		 7930 /*
7931 * Make sure we're properly removed from the ordered operation
7932 * lists.
7933 */
7934 smp_mb();
7935 if (!list_empty(&BTRFS_I(inode)->ordered_operations)) {
7936 spin_lock(&root->fs_info->ordered_extent_lock);
7937 list_del_init(&BTRFS_I(inode)->ordered_operations);
7938 spin_unlock(&root->fs_info->ordered_extent_lock);
7939 }
7940
8a35d95f
JB		 7941 if (test_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
7942 &BTRFS_I(inode)->runtime_flags)) {
33345d01
LZ		 7943 printk(KERN_INFO "BTRFS: inode %llu still on the orphan list\n",
7944 (unsigned long long)btrfs_ino(inode));
8a35d95f 7945 atomic_dec(&root->orphan_inodes);
7b128766 7946 }
7b128766 7947
d397712b 7948 while (1) {
e6dcd2dc
CM		 7949 ordered = btrfs_lookup_first_ordered_extent(inode, (u64)-1);
7950 if (!ordered)
7951 break;
7952 else {
d397712b
CM		 7953 printk(KERN_ERR "btrfs found ordered "
7954 "extent %llu %llu on inode cleanup\n",
7955 (unsigned long long)ordered->file_offset,
7956 (unsigned long long)ordered->len);
e6dcd2dc
CM		 7957 btrfs_remove_ordered_extent(inode, ordered);
7958 btrfs_put_ordered_extent(ordered);
7959 btrfs_put_ordered_extent(ordered);
7960 }
7961 }
5d4f98a2 7962 inode_tree_del(inode);
5b21f2ed 7963 btrfs_drop_extent_cache(inode, 0, (u64)-1, 0);
a6dbd429 7964free:
16cdcec7 7965 btrfs_remove_delayed_node(inode);
fa0d7e3d 7966 call_rcu(&inode->i_rcu, btrfs_i_callback);
39279cc3
CM		 7967}
7968
45321ac5 7969int btrfs_drop_inode(struct inode *inode)
76dda93c
YZ		 7970{
7971 struct btrfs_root *root = BTRFS_I(inode)->root;
45321ac5 7972
fa6ac876 7973 /* the snap/subvol tree is on deleting */
0af3d00b 7974 if (btrfs_root_refs(&root->root_item) == 0 &&
fa6ac876 7975 root != root->fs_info->tree_root)
45321ac5 7976 return 1;
76dda93c 7977 else
45321ac5 7978 return generic_drop_inode(inode);
76dda93c
YZ		 7979}
7980
0ee0fda0 7981static void init_once(void *foo)
39279cc3
CM		 7982{
7983 struct btrfs_inode *ei = (struct btrfs_inode *) foo;
7984
7985 inode_init_once(&ei->vfs_inode);
7986}
7987
7988void btrfs_destroy_cachep(void)
7989{
8c0a8537
KS		 7990 /*
7991 * Make sure all delayed rcu free inodes are flushed before we
7992 * destroy cache.
7993 */
7994 rcu_barrier();
39279cc3
CM		 7995 if (btrfs_inode_cachep)
7996 kmem_cache_destroy(btrfs_inode_cachep);
7997 if (btrfs_trans_handle_cachep)
7998 kmem_cache_destroy(btrfs_trans_handle_cachep);
7999 if (btrfs_transaction_cachep)
8000 kmem_cache_destroy(btrfs_transaction_cachep);
39279cc3
CM		 8001 if (btrfs_path_cachep)
8002 kmem_cache_destroy(btrfs_path_cachep);
dc89e982
JB		 8003 if (btrfs_free_space_cachep)
8004 kmem_cache_destroy(btrfs_free_space_cachep);
8ccf6f19
MX		 8005 if (btrfs_delalloc_work_cachep)
8006 kmem_cache_destroy(btrfs_delalloc_work_cachep);
39279cc3
CM		 8007}
8008
8009int btrfs_init_cachep(void)
8010{
837e1972 8011 btrfs_inode_cachep = kmem_cache_create("btrfs_inode",
9601e3f6
CH		 8012 sizeof(struct btrfs_inode), 0,
8013 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, init_once);
39279cc3
CM		 8014 if (!btrfs_inode_cachep)
8015 goto fail;
9601e3f6 8016
837e1972 8017 btrfs_trans_handle_cachep = kmem_cache_create("btrfs_trans_handle",
9601e3f6
CH		 8018 sizeof(struct btrfs_trans_handle), 0,
8019 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
39279cc3
CM		 8020 if (!btrfs_trans_handle_cachep)
8021 goto fail;
9601e3f6 8022
837e1972 8023 btrfs_transaction_cachep = kmem_cache_create("btrfs_transaction",
9601e3f6
CH		 8024 sizeof(struct btrfs_transaction), 0,
8025 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
39279cc3
CM		 8026 if (!btrfs_transaction_cachep)
8027 goto fail;
9601e3f6 8028
837e1972 8029 btrfs_path_cachep = kmem_cache_create("btrfs_path",
9601e3f6
CH		 8030 sizeof(struct btrfs_path), 0,
8031 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
39279cc3
CM		 8032 if (!btrfs_path_cachep)
8033 goto fail;
9601e3f6 8034
837e1972 8035 btrfs_free_space_cachep = kmem_cache_create("btrfs_free_space",
dc89e982
JB		 8036 sizeof(struct btrfs_free_space), 0,
8037 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
8038 if (!btrfs_free_space_cachep)
8039 goto fail;
8040
8ccf6f19
MX		 8041 btrfs_delalloc_work_cachep = kmem_cache_create("btrfs_delalloc_work",
8042 sizeof(struct btrfs_delalloc_work), 0,
8043 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
8044 NULL);
8045 if (!btrfs_delalloc_work_cachep)
8046 goto fail;
8047
39279cc3
CM		 8048 return 0;
8049fail:
8050 btrfs_destroy_cachep();
8051 return -ENOMEM;
8052}
8053
8054static int btrfs_getattr(struct vfsmount *mnt,
8055 struct dentry *dentry, struct kstat *stat)
8056{
df0af1a5 8057 u64 delalloc_bytes;
39279cc3 8058 struct inode *inode = dentry->d_inode;
fadc0d8b
DS		 8059 u32 blocksize = inode->i_sb->s_blocksize;
8060
39279cc3 8061 generic_fillattr(inode, stat);
0ee5dc67 8062 stat->dev = BTRFS_I(inode)->root->anon_dev;
d6667462 8063 stat->blksize = PAGE_CACHE_SIZE;
df0af1a5
MX		 8064
8065 spin_lock(&BTRFS_I(inode)->lock);
8066 delalloc_bytes = BTRFS_I(inode)->delalloc_bytes;
8067 spin_unlock(&BTRFS_I(inode)->lock);
fadc0d8b 8068 stat->blocks = (ALIGN(inode_get_bytes(inode), blocksize) +
df0af1a5 8069 ALIGN(delalloc_bytes, blocksize)) >> 9;
39279cc3
CM		 8070 return 0;
8071}
8072
d397712b
CM		 8073static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry,
8074 struct inode *new_dir, struct dentry *new_dentry)
39279cc3
CM		 8075{
8076 struct btrfs_trans_handle *trans;
8077 struct btrfs_root *root = BTRFS_I(old_dir)->root;
4df27c4d 8078 struct btrfs_root *dest = BTRFS_I(new_dir)->root;
39279cc3
CM		 8079 struct inode *new_inode = new_dentry->d_inode;
8080 struct inode *old_inode = old_dentry->d_inode;
8081 struct timespec ctime = CURRENT_TIME;
00e4e6b3 8082 u64 index = 0;
4df27c4d 8083 u64 root_objectid;
39279cc3 8084 int ret;
33345d01 8085 u64 old_ino = btrfs_ino(old_inode);
39279cc3 8086
33345d01 8087 if (btrfs_ino(new_dir) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
f679a840
YZ		 8088 return -EPERM;
8089
4df27c4d 8090 /* we only allow rename subvolume link between subvolumes */
33345d01 8091 if (old_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest)
3394e160
CM		 8092 return -EXDEV;
8093
33345d01
LZ		 8094 if (old_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID ||
8095 (new_inode && btrfs_ino(new_inode) == BTRFS_FIRST_FREE_OBJECTID))
39279cc3 8096 return -ENOTEMPTY;
5f39d397 8097
4df27c4d
YZ		 8098 if (S_ISDIR(old_inode->i_mode) && new_inode &&
8099 new_inode->i_size > BTRFS_EMPTY_DIR_SIZE)
8100 return -ENOTEMPTY;
9c52057c
CM		 8101
8102
8103 /* check for collisions, even if the name isn't there */
8104 ret = btrfs_check_dir_item_collision(root, new_dir->i_ino,
8105 new_dentry->d_name.name,
8106 new_dentry->d_name.len);
8107
8108 if (ret) {
8109 if (ret == -EEXIST) {
8110 /* we shouldn't get
8111 * eexist without a new_inode */
8112 if (!new_inode) {
8113 WARN_ON(1);
8114 return ret;
8115 }
8116 } else {
8117 /* maybe -EOVERFLOW */
8118 return ret;
8119 }
8120 }
8121 ret = 0;
8122
5a3f23d5
CM		 8123 /*
8124 * we're using rename to replace one file with another.
8125 * and the replacement file is large. Start IO on it now so
8126 * we don't add too much work to the end of the transaction
8127 */
4baf8c92 8128 if (new_inode && S_ISREG(old_inode->i_mode) && new_inode->i_size &&
5a3f23d5
CM		 8129 old_inode->i_size > BTRFS_ORDERED_OPERATIONS_FLUSH_LIMIT)
8130 filemap_flush(old_inode->i_mapping);
8131
76dda93c 8132 /* close the racy window with snapshot create/destroy ioctl */
33345d01 8133 if (old_ino == BTRFS_FIRST_FREE_OBJECTID)
76dda93c 8134 down_read(&root->fs_info->subvol_sem);
a22285a6
YZ		 8135 /*
8136 * We want to reserve the absolute worst case amount of items. So if
8137 * both inodes are subvols and we need to unlink them then that would
8138 * require 4 item modifications, but if they are both normal inodes it
8139 * would require 5 item modifications, so we'll assume their normal
8140 * inodes. So 5 * 2 is 10, plus 1 for the new link, so 11 total items
8141 * should cover the worst case number of items we'll modify.
8142 */
6e137ed3 8143 trans = btrfs_start_transaction(root, 11);
b44c59a8
JL		 8144 if (IS_ERR(trans)) {
8145 ret = PTR_ERR(trans);
8146 goto out_notrans;
8147 }
76dda93c 8148
4df27c4d
YZ		 8149 if (dest != root)
8150 btrfs_record_root_in_trans(trans, dest);
5f39d397 8151
a5719521
YZ		 8152 ret = btrfs_set_inode_index(new_dir, &index);
8153 if (ret)
8154 goto out_fail;
5a3f23d5 8155
33345d01 8156 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) {
4df27c4d
YZ		 8157 /* force full log commit if subvolume involved. */
8158 root->fs_info->last_trans_log_full_commit = trans->transid;
8159 } else {
a5719521
YZ		 8160 ret = btrfs_insert_inode_ref(trans, dest,
8161 new_dentry->d_name.name,
8162 new_dentry->d_name.len,
33345d01
LZ		 8163 old_ino,
8164 btrfs_ino(new_dir), index);
a5719521
YZ		 8165 if (ret)
8166 goto out_fail;
4df27c4d
YZ		 8167 /*
8168 * this is an ugly little race, but the rename is required
8169 * to make sure that if we crash, the inode is either at the
8170 * old name or the new one. pinning the log transaction lets
8171 * us make sure we don't allow a log commit to come in after
8172 * we unlink the name but before we add the new name back in.
8173 */
8174 btrfs_pin_log_trans(root);
8175 }
5a3f23d5
CM		 8176 /*
8177 * make sure the inode gets flushed if it is replacing
8178 * something.
8179 */
33345d01 8180 if (new_inode && new_inode->i_size && S_ISREG(old_inode->i_mode))
5a3f23d5 8181 btrfs_add_ordered_operation(trans, root, old_inode);
5a3f23d5 8182
0c4d2d95
JB		 8183 inode_inc_iversion(old_dir);
8184 inode_inc_iversion(new_dir);
8185 inode_inc_iversion(old_inode);
39279cc3
CM		 8186 old_dir->i_ctime = old_dir->i_mtime = ctime;
8187 new_dir->i_ctime = new_dir->i_mtime = ctime;
8188 old_inode->i_ctime = ctime;
5f39d397 8189
12fcfd22
CM		 8190 if (old_dentry->d_parent != new_dentry->d_parent)
8191 btrfs_record_unlink_dir(trans, old_dir, old_inode, 1);
8192
33345d01 8193 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) {
4df27c4d
YZ		 8194 root_objectid = BTRFS_I(old_inode)->root->root_key.objectid;
8195 ret = btrfs_unlink_subvol(trans, root, old_dir, root_objectid,
8196 old_dentry->d_name.name,
8197 old_dentry->d_name.len);
8198 } else {
92986796
AV		 8199 ret = __btrfs_unlink_inode(trans, root, old_dir,
8200 old_dentry->d_inode,
8201 old_dentry->d_name.name,
8202 old_dentry->d_name.len);
8203 if (!ret)
8204 ret = btrfs_update_inode(trans, root, old_inode);
4df27c4d 8205 }
79787eaa
JM		 8206 if (ret) {
8207 btrfs_abort_transaction(trans, root, ret);
8208 goto out_fail;
8209 }
39279cc3
CM		 8210
8211 if (new_inode) {
0c4d2d95 8212 inode_inc_iversion(new_inode);
39279cc3 8213 new_inode->i_ctime = CURRENT_TIME;
33345d01 8214 if (unlikely(btrfs_ino(new_inode) ==
4df27c4d
YZ		 8215 BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
8216 root_objectid = BTRFS_I(new_inode)->location.objectid;
8217 ret = btrfs_unlink_subvol(trans, dest, new_dir,
8218 root_objectid,
8219 new_dentry->d_name.name,
8220 new_dentry->d_name.len);
8221 BUG_ON(new_inode->i_nlink == 0);
8222 } else {
8223 ret = btrfs_unlink_inode(trans, dest, new_dir,
8224 new_dentry->d_inode,
8225 new_dentry->d_name.name,
8226 new_dentry->d_name.len);
8227 }
79787eaa 8228 if (!ret && new_inode->i_nlink == 0) {
e02119d5 8229 ret = btrfs_orphan_add(trans, new_dentry->d_inode);
4df27c4d 8230 BUG_ON(ret);
7b128766 8231 }
79787eaa
JM		 8232 if (ret) {
8233 btrfs_abort_transaction(trans, root, ret);
8234 goto out_fail;
8235 }
39279cc3 8236 }
aec7477b 8237
4df27c4d
YZ		 8238 ret = btrfs_add_link(trans, new_dir, old_inode,
8239 new_dentry->d_name.name,
a5719521 8240 new_dentry->d_name.len, 0, index);
79787eaa
JM		 8241 if (ret) {
8242 btrfs_abort_transaction(trans, root, ret);
8243 goto out_fail;
8244 }
39279cc3 8245
33345d01 8246 if (old_ino != BTRFS_FIRST_FREE_OBJECTID) {
10d9f309 8247 struct dentry *parent = new_dentry->d_parent;
6a912213 8248 btrfs_log_new_name(trans, old_inode, old_dir, parent);
4df27c4d
YZ		 8249 btrfs_end_log_trans(root);
8250 }
39279cc3 8251out_fail:
7ad85bb7 8252 btrfs_end_transaction(trans, root);
b44c59a8 8253out_notrans:
33345d01 8254 if (old_ino == BTRFS_FIRST_FREE_OBJECTID)
76dda93c 8255 up_read(&root->fs_info->subvol_sem);
9ed74f2d 8256
39279cc3
CM		 8257 return ret;
8258}
8259
8ccf6f19
MX		 8260static void btrfs_run_delalloc_work(struct btrfs_work *work)
8261{
8262 struct btrfs_delalloc_work *delalloc_work;
8263
8264 delalloc_work = container_of(work, struct btrfs_delalloc_work,
8265 work);
8266 if (delalloc_work->wait)
8267 btrfs_wait_ordered_range(delalloc_work->inode, 0, (u64)-1);
8268 else
8269 filemap_flush(delalloc_work->inode->i_mapping);
8270
8271 if (delalloc_work->delay_iput)
8272 btrfs_add_delayed_iput(delalloc_work->inode);
8273 else
8274 iput(delalloc_work->inode);
8275 complete(&delalloc_work->completion);
8276}
8277
8278struct btrfs_delalloc_work *btrfs_alloc_delalloc_work(struct inode *inode,
8279 int wait, int delay_iput)
8280{
8281 struct btrfs_delalloc_work *work;
8282
8283 work = kmem_cache_zalloc(btrfs_delalloc_work_cachep, GFP_NOFS);
8284 if (!work)
8285 return NULL;
8286
8287 init_completion(&work->completion);
8288 INIT_LIST_HEAD(&work->list);
8289 work->inode = inode;
8290 work->wait = wait;
8291 work->delay_iput = delay_iput;
8292 work->work.func = btrfs_run_delalloc_work;
8293
8294 return work;
8295}
8296
8297void btrfs_wait_and_free_delalloc_work(struct btrfs_delalloc_work *work)
8298{
8299 wait_for_completion(&work->completion);
8300 kmem_cache_free(btrfs_delalloc_work_cachep, work);
8301}
8302
d352ac68
CM		 8303/*
8304 * some fairly slow code that needs optimization. This walks the list
8305 * of all the inodes with pending delalloc and forces them to disk.
8306 */
24bbcf04 8307int btrfs_start_delalloc_inodes(struct btrfs_root *root, int delay_iput)
ea8c2819 8308{
ea8c2819 8309 struct btrfs_inode *binode;
5b21f2ed 8310 struct inode *inode;
8ccf6f19
MX		 8311 struct btrfs_delalloc_work *work, *next;
8312 struct list_head works;
1eafa6c7 8313 struct list_head splice;
8ccf6f19 8314 int ret = 0;
ea8c2819 8315
c146afad
YZ		 8316 if (root->fs_info->sb->s_flags & MS_RDONLY)
8317 return -EROFS;
8318
8ccf6f19 8319 INIT_LIST_HEAD(&works);
1eafa6c7 8320 INIT_LIST_HEAD(&splice);
63607cc8 8321
75eff68e 8322 spin_lock(&root->fs_info->delalloc_lock);
1eafa6c7
MX		 8323 list_splice_init(&root->fs_info->delalloc_inodes, &splice);
8324 while (!list_empty(&splice)) {
8325 binode = list_entry(splice.next, struct btrfs_inode,
ea8c2819 8326 delalloc_inodes);
1eafa6c7
MX		 8327
8328 list_del_init(&binode->delalloc_inodes);
8329
5b21f2ed 8330 inode = igrab(&binode->vfs_inode);
df0af1a5
MX		 8331 if (!inode) {
8332 clear_bit(BTRFS_INODE_IN_DELALLOC_LIST,
8333 &binode->runtime_flags);
1eafa6c7 8334 continue;
df0af1a5 8335 }
1eafa6c7
MX		 8336
8337 list_add_tail(&binode->delalloc_inodes,
8338 &root->fs_info->delalloc_inodes);
75eff68e 8339 spin_unlock(&root->fs_info->delalloc_lock);
1eafa6c7
MX		 8340
8341 work = btrfs_alloc_delalloc_work(inode, 0, delay_iput);
8342 if (unlikely(!work)) {
8343 ret = -ENOMEM;
8344 goto out;
5b21f2ed 8345 }
1eafa6c7
MX		 8346 list_add_tail(&work->list, &works);
8347 btrfs_queue_worker(&root->fs_info->flush_workers,
8348 &work->work);
8349
5b21f2ed 8350 cond_resched();
75eff68e 8351 spin_lock(&root->fs_info->delalloc_lock);
ea8c2819 8352 }
75eff68e 8353 spin_unlock(&root->fs_info->delalloc_lock);
8c8bee1d 8354
1eafa6c7
MX		 8355 list_for_each_entry_safe(work, next, &works, list) {
8356 list_del_init(&work->list);
8357 btrfs_wait_and_free_delalloc_work(work);
8358 }
8359
8c8bee1d
CM		 8360 /* the filemap_flush will queue IO into the worker threads, but
8361 * we have to make sure the IO is actually started and that
8362 * ordered extents get created before we return
8363 */
8364 atomic_inc(&root->fs_info->async_submit_draining);
d397712b 8365 while (atomic_read(&root->fs_info->nr_async_submits) ||
771ed689 8366 atomic_read(&root->fs_info->async_delalloc_pages)) {
8c8bee1d 8367 wait_event(root->fs_info->async_submit_wait,
771ed689
CM		 8368 (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
8369 atomic_read(&root->fs_info->async_delalloc_pages) == 0));
8c8bee1d
CM		 8370 }
8371 atomic_dec(&root->fs_info->async_submit_draining);
1eafa6c7 8372 return 0;
8ccf6f19
MX		 8373out:
8374 list_for_each_entry_safe(work, next, &works, list) {
8375 list_del_init(&work->list);
8376 btrfs_wait_and_free_delalloc_work(work);
8377 }
1eafa6c7
MX		 8378
8379 if (!list_empty_careful(&splice)) {
8380 spin_lock(&root->fs_info->delalloc_lock);
8381 list_splice_tail(&splice, &root->fs_info->delalloc_inodes);
8382 spin_unlock(&root->fs_info->delalloc_lock);
8383 }
8ccf6f19 8384 return ret;
ea8c2819
CM		 8385}
8386
39279cc3
CM		 8387static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
8388 const char *symname)
8389{
8390 struct btrfs_trans_handle *trans;
8391 struct btrfs_root *root = BTRFS_I(dir)->root;
8392 struct btrfs_path *path;
8393 struct btrfs_key key;
1832a6d5 8394 struct inode *inode = NULL;
39279cc3
CM		 8395 int err;
8396 int drop_inode = 0;
8397 u64 objectid;
00e4e6b3 8398 u64 index = 0 ;
39279cc3
CM		 8399 int name_len;
8400 int datasize;
5f39d397 8401 unsigned long ptr;
39279cc3 8402 struct btrfs_file_extent_item *ei;
5f39d397 8403 struct extent_buffer *leaf;
39279cc3
CM		 8404
8405 name_len = strlen(symname) + 1;
8406 if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(root))
8407 return -ENAMETOOLONG;
1832a6d5 8408
9ed74f2d
JB		 8409 /*
8410 * 2 items for inode item and ref
8411 * 2 items for dir items
8412 * 1 item for xattr if selinux is on
8413 */
a22285a6
YZ		 8414 trans = btrfs_start_transaction(root, 5);
8415 if (IS_ERR(trans))
8416 return PTR_ERR(trans);
1832a6d5 8417
581bb050
LZ		 8418 err = btrfs_find_free_ino(root, &objectid);
8419 if (err)
8420 goto out_unlock;
8421
aec7477b 8422 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
33345d01 8423 dentry->d_name.len, btrfs_ino(dir), objectid,
d82a6f1d 8424 S_IFLNK|S_IRWXUGO, &index);
7cf96da3
TI		 8425 if (IS_ERR(inode)) {
8426 err = PTR_ERR(inode);
39279cc3 8427 goto out_unlock;
7cf96da3 8428 }
39279cc3 8429
2a7dba39 8430 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
33268eaf
JB		 8431 if (err) {
8432 drop_inode = 1;
8433 goto out_unlock;
8434 }
8435
ad19db71
CS		 8436 /*
8437 * If the active LSM wants to access the inode during
8438 * d_instantiate it needs these. Smack checks to see
8439 * if the filesystem supports xattrs by looking at the
8440 * ops vector.
8441 */
8442 inode->i_fop = &btrfs_file_operations;
8443 inode->i_op = &btrfs_file_inode_operations;
8444
a1b075d2 8445 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
39279cc3
CM		 8446 if (err)
8447 drop_inode = 1;
8448 else {
8449 inode->i_mapping->a_ops = &btrfs_aops;
04160088 8450 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
d1310b2e 8451 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
39279cc3 8452 }
39279cc3
CM		 8453 if (drop_inode)
8454 goto out_unlock;
8455
8456 path = btrfs_alloc_path();
d8926bb3
MF		 8457 if (!path) {
8458 err = -ENOMEM;
8459 drop_inode = 1;
8460 goto out_unlock;
8461 }
33345d01 8462 key.objectid = btrfs_ino(inode);
39279cc3 8463 key.offset = 0;
39279cc3
CM		 8464 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
8465 datasize = btrfs_file_extent_calc_inline_size(name_len);
8466 err = btrfs_insert_empty_item(trans, root, path, &key,
8467 datasize);
54aa1f4d
CM		 8468 if (err) {
8469 drop_inode = 1;
b0839166 8470 btrfs_free_path(path);
54aa1f4d
CM		 8471 goto out_unlock;
8472 }
5f39d397
CM		 8473 leaf = path->nodes[0];
8474 ei = btrfs_item_ptr(leaf, path->slots[0],
8475 struct btrfs_file_extent_item);
8476 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
8477 btrfs_set_file_extent_type(leaf, ei,
39279cc3 8478 BTRFS_FILE_EXTENT_INLINE);
c8b97818
CM		 8479 btrfs_set_file_extent_encryption(leaf, ei, 0);
8480 btrfs_set_file_extent_compression(leaf, ei, 0);
8481 btrfs_set_file_extent_other_encoding(leaf, ei, 0);
8482 btrfs_set_file_extent_ram_bytes(leaf, ei, name_len);
8483
39279cc3 8484 ptr = btrfs_file_extent_inline_start(ei);
5f39d397
CM		 8485 write_extent_buffer(leaf, symname, ptr, name_len);
8486 btrfs_mark_buffer_dirty(leaf);
39279cc3 8487 btrfs_free_path(path);
5f39d397 8488
39279cc3
CM		 8489 inode->i_op = &btrfs_symlink_inode_operations;
8490 inode->i_mapping->a_ops = &btrfs_symlink_aops;
04160088 8491 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
d899e052 8492 inode_set_bytes(inode, name_len);
dbe674a9 8493 btrfs_i_size_write(inode, name_len - 1);
54aa1f4d
CM		 8494 err = btrfs_update_inode(trans, root, inode);
8495 if (err)
8496 drop_inode = 1;
39279cc3
CM		 8497
8498out_unlock:
08c422c2
AV		 8499 if (!err)
8500 d_instantiate(dentry, inode);
7ad85bb7 8501 btrfs_end_transaction(trans, root);
39279cc3
CM		 8502 if (drop_inode) {
8503 inode_dec_link_count(inode);
8504 iput(inode);
8505 }
b53d3f5d 8506 btrfs_btree_balance_dirty(root);
39279cc3
CM		 8507 return err;
8508}
16432985 8509
0af3d00b
JB		 8510static int __btrfs_prealloc_file_range(struct inode *inode, int mode,
8511 u64 start, u64 num_bytes, u64 min_size,
8512 loff_t actual_len, u64 *alloc_hint,
8513 struct btrfs_trans_handle *trans)
d899e052 8514{
5dc562c5
JB		 8515 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
8516 struct extent_map *em;
d899e052
YZ		 8517 struct btrfs_root *root = BTRFS_I(inode)->root;
8518 struct btrfs_key ins;
d899e052 8519 u64 cur_offset = start;
55a61d1d 8520 u64 i_size;
154ea289 8521 u64 cur_bytes;
d899e052 8522 int ret = 0;
0af3d00b 8523 bool own_trans = true;
d899e052 8524
0af3d00b
JB		 8525 if (trans)
8526 own_trans = false;
d899e052 8527 while (num_bytes > 0) {
0af3d00b
JB		 8528 if (own_trans) {
8529 trans = btrfs_start_transaction(root, 3);
8530 if (IS_ERR(trans)) {
8531 ret = PTR_ERR(trans);
8532 break;
8533 }
5a303d5d
YZ		 8534 }
8535
154ea289
CM		 8536 cur_bytes = min(num_bytes, 256ULL * 1024 * 1024);
8537 cur_bytes = max(cur_bytes, min_size);
8538 ret = btrfs_reserve_extent(trans, root, cur_bytes,
24542bf7 8539 min_size, 0, *alloc_hint, &ins, 1);
5a303d5d 8540 if (ret) {
0af3d00b
JB		 8541 if (own_trans)
8542 btrfs_end_transaction(trans, root);
a22285a6 8543 break;
d899e052 8544 }
5a303d5d 8545
d899e052
YZ		 8546 ret = insert_reserved_file_extent(trans, inode,
8547 cur_offset, ins.objectid,
8548 ins.offset, ins.offset,
920bbbfb 8549 ins.offset, 0, 0, 0,
d899e052 8550 BTRFS_FILE_EXTENT_PREALLOC);
79787eaa
JM		 8551 if (ret) {
8552 btrfs_abort_transaction(trans, root, ret);
8553 if (own_trans)
8554 btrfs_end_transaction(trans, root);
8555 break;
8556 }
a1ed835e
CM		 8557 btrfs_drop_extent_cache(inode, cur_offset,
8558 cur_offset + ins.offset -1, 0);
5a303d5d 8559
5dc562c5
JB		 8560 em = alloc_extent_map();
8561 if (!em) {
8562 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
8563 &BTRFS_I(inode)->runtime_flags);
8564 goto next;
8565 }
8566
8567 em->start = cur_offset;
8568 em->orig_start = cur_offset;
8569 em->len = ins.offset;
8570 em->block_start = ins.objectid;
8571 em->block_len = ins.offset;
b4939680 8572 em->orig_block_len = ins.offset;
5dc562c5
JB		 8573 em->bdev = root->fs_info->fs_devices->latest_bdev;
8574 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
8575 em->generation = trans->transid;
8576
8577 while (1) {
8578 write_lock(&em_tree->lock);
8579 ret = add_extent_mapping(em_tree, em);
8580 if (!ret)
8581 list_move(&em->list,
8582 &em_tree->modified_extents);
8583 write_unlock(&em_tree->lock);
8584 if (ret != -EEXIST)
8585 break;
8586 btrfs_drop_extent_cache(inode, cur_offset,
8587 cur_offset + ins.offset - 1,
8588 0);
8589 }
8590 free_extent_map(em);
8591next:
d899e052
YZ		 8592 num_bytes -= ins.offset;
8593 cur_offset += ins.offset;
efa56464 8594 *alloc_hint = ins.objectid + ins.offset;
5a303d5d 8595
0c4d2d95 8596 inode_inc_iversion(inode);
d899e052 8597 inode->i_ctime = CURRENT_TIME;
6cbff00f 8598 BTRFS_I(inode)->flags |= BTRFS_INODE_PREALLOC;
d899e052 8599 if (!(mode & FALLOC_FL_KEEP_SIZE) &&
efa56464
YZ		 8600 (actual_len > inode->i_size) &&
8601 (cur_offset > inode->i_size)) {
d1ea6a61 8602 if (cur_offset > actual_len)
55a61d1d 8603 i_size = actual_len;
d1ea6a61 8604 else
55a61d1d
JB		 8605 i_size = cur_offset;
8606 i_size_write(inode, i_size);
8607 btrfs_ordered_update_i_size(inode, i_size, NULL);
5a303d5d
YZ		 8608 }
8609
d899e052 8610 ret = btrfs_update_inode(trans, root, inode);
79787eaa
JM		 8611
8612 if (ret) {
8613 btrfs_abort_transaction(trans, root, ret);
8614 if (own_trans)
8615 btrfs_end_transaction(trans, root);
8616 break;
8617 }
d899e052 8618
0af3d00b
JB		 8619 if (own_trans)
8620 btrfs_end_transaction(trans, root);
5a303d5d 8621 }
d899e052
YZ		 8622 return ret;
8623}
8624
0af3d00b
JB		 8625int btrfs_prealloc_file_range(struct inode *inode, int mode,
8626 u64 start, u64 num_bytes, u64 min_size,
8627 loff_t actual_len, u64 *alloc_hint)
8628{
8629 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes,
8630 min_size, actual_len, alloc_hint,
8631 NULL);
8632}
8633
8634int btrfs_prealloc_file_range_trans(struct inode *inode,
8635 struct btrfs_trans_handle *trans, int mode,
8636 u64 start, u64 num_bytes, u64 min_size,
8637 loff_t actual_len, u64 *alloc_hint)
8638{
8639 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes,
8640 min_size, actual_len, alloc_hint, trans);
8641}
8642
e6dcd2dc
CM		 8643static int btrfs_set_page_dirty(struct page *page)
8644{
e6dcd2dc
CM		 8645 return __set_page_dirty_nobuffers(page);
8646}
8647
10556cb2 8648static int btrfs_permission(struct inode *inode, int mask)
fdebe2bd 8649{
b83cc969 8650 struct btrfs_root *root = BTRFS_I(inode)->root;
cb6db4e5 8651 umode_t mode = inode->i_mode;
b83cc969 8652
cb6db4e5
JM		 8653 if (mask & MAY_WRITE &&
8654 (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))) {
8655 if (btrfs_root_readonly(root))
8656 return -EROFS;
8657 if (BTRFS_I(inode)->flags & BTRFS_INODE_READONLY)
8658 return -EACCES;
8659 }
2830ba7f 8660 return generic_permission(inode, mask);
fdebe2bd 8661}
39279cc3 8662
6e1d5dcc 8663static const struct inode_operations btrfs_dir_inode_operations = {
3394e160 8664 .getattr = btrfs_getattr,
39279cc3
CM		 8665 .lookup = btrfs_lookup,
8666 .create = btrfs_create,
8667 .unlink = btrfs_unlink,
8668 .link = btrfs_link,
8669 .mkdir = btrfs_mkdir,
8670 .rmdir = btrfs_rmdir,
8671 .rename = btrfs_rename,
8672 .symlink = btrfs_symlink,
8673 .setattr = btrfs_setattr,
618e21d5 8674 .mknod = btrfs_mknod,
95819c05
CH		 8675 .setxattr = btrfs_setxattr,
8676 .getxattr = btrfs_getxattr,
5103e947 8677 .listxattr = btrfs_listxattr,
95819c05 8678 .removexattr = btrfs_removexattr,
fdebe2bd 8679 .permission = btrfs_permission,
4e34e719 8680 .get_acl = btrfs_get_acl,
39279cc3 8681};
6e1d5dcc 8682static const struct inode_operations btrfs_dir_ro_inode_operations = {
39279cc3 8683 .lookup = btrfs_lookup,
fdebe2bd 8684 .permission = btrfs_permission,
4e34e719 8685 .get_acl = btrfs_get_acl,
39279cc3 8686};
76dda93c 8687
828c0950 8688static const struct file_operations btrfs_dir_file_operations = {
39279cc3
CM		 8689 .llseek = generic_file_llseek,
8690 .read = generic_read_dir,
cbdf5a24 8691 .readdir = btrfs_real_readdir,
34287aa3 8692 .unlocked_ioctl = btrfs_ioctl,
39279cc3 8693#ifdef CONFIG_COMPAT
34287aa3 8694 .compat_ioctl = btrfs_ioctl,
39279cc3 8695#endif
6bf13c0c 8696 .release = btrfs_release_file,
e02119d5 8697 .fsync = btrfs_sync_file,
39279cc3
CM		 8698};
8699
d1310b2e 8700static struct extent_io_ops btrfs_extent_io_ops = {
07157aac 8701 .fill_delalloc = run_delalloc_range,
065631f6 8702 .submit_bio_hook = btrfs_submit_bio_hook,
239b14b3 8703 .merge_bio_hook = btrfs_merge_bio_hook,
07157aac 8704 .readpage_end_io_hook = btrfs_readpage_end_io_hook,
e6dcd2dc 8705 .writepage_end_io_hook = btrfs_writepage_end_io_hook,
247e743c 8706 .writepage_start_hook = btrfs_writepage_start_hook,
b0c68f8b
CM		 8707 .set_bit_hook = btrfs_set_bit_hook,
8708 .clear_bit_hook = btrfs_clear_bit_hook,
9ed74f2d
JB		 8709 .merge_extent_hook = btrfs_merge_extent_hook,
8710 .split_extent_hook = btrfs_split_extent_hook,
07157aac
CM		 8711};
8712
35054394
CM		 8713/*
8714 * btrfs doesn't support the bmap operation because swapfiles
8715 * use bmap to make a mapping of extents in the file. They assume
8716 * these extents won't change over the life of the file and they
8717 * use the bmap result to do IO directly to the drive.
8718 *
8719 * the btrfs bmap call would return logical addresses that aren't
8720 * suitable for IO and they also will change frequently as COW
8721 * operations happen. So, swapfile + btrfs == corruption.
8722 *
8723 * For now we're avoiding this by dropping bmap.
8724 */
7f09410b 8725static const struct address_space_operations btrfs_aops = {
39279cc3
CM		 8726 .readpage = btrfs_readpage,
8727 .writepage = btrfs_writepage,
b293f02e 8728 .writepages = btrfs_writepages,
3ab2fb5a 8729 .readpages = btrfs_readpages,
16432985 8730 .direct_IO = btrfs_direct_IO,
a52d9a80
CM		 8731 .invalidatepage = btrfs_invalidatepage,
8732 .releasepage = btrfs_releasepage,
e6dcd2dc 8733 .set_page_dirty = btrfs_set_page_dirty,
465fdd97 8734 .error_remove_page = generic_error_remove_page,
39279cc3
CM		 8735};
8736
7f09410b 8737static const struct address_space_operations btrfs_symlink_aops = {
39279cc3
CM		 8738 .readpage = btrfs_readpage,
8739 .writepage = btrfs_writepage,
2bf5a725
CM		 8740 .invalidatepage = btrfs_invalidatepage,
8741 .releasepage = btrfs_releasepage,
39279cc3
CM		 8742};
8743
6e1d5dcc 8744static const struct inode_operations btrfs_file_inode_operations = {
39279cc3
CM		 8745 .getattr = btrfs_getattr,
8746 .setattr = btrfs_setattr,
95819c05
CH		 8747 .setxattr = btrfs_setxattr,
8748 .getxattr = btrfs_getxattr,
5103e947 8749 .listxattr = btrfs_listxattr,
95819c05 8750 .removexattr = btrfs_removexattr,
fdebe2bd 8751 .permission = btrfs_permission,
1506fcc8 8752 .fiemap = btrfs_fiemap,
4e34e719 8753 .get_acl = btrfs_get_acl,
e41f941a 8754 .update_time = btrfs_update_time,
39279cc3 8755};
6e1d5dcc 8756static const struct inode_operations btrfs_special_inode_operations = {
618e21d5
JB		 8757 .getattr = btrfs_getattr,
8758 .setattr = btrfs_setattr,
fdebe2bd 8759 .permission = btrfs_permission,
95819c05
CH		 8760 .setxattr = btrfs_setxattr,
8761 .getxattr = btrfs_getxattr,
33268eaf 8762 .listxattr = btrfs_listxattr,
95819c05 8763 .removexattr = btrfs_removexattr,
4e34e719 8764 .get_acl = btrfs_get_acl,
e41f941a 8765 .update_time = btrfs_update_time,
618e21d5 8766};
6e1d5dcc 8767static const struct inode_operations btrfs_symlink_inode_operations = {
39279cc3
CM		 8768 .readlink = generic_readlink,
8769 .follow_link = page_follow_link_light,
8770 .put_link = page_put_link,
f209561a 8771 .getattr = btrfs_getattr,
22c44fe6 8772 .setattr = btrfs_setattr,
fdebe2bd 8773 .permission = btrfs_permission,
0279b4cd
JO		 8774 .setxattr = btrfs_setxattr,
8775 .getxattr = btrfs_getxattr,
8776 .listxattr = btrfs_listxattr,
8777 .removexattr = btrfs_removexattr,
4e34e719 8778 .get_acl = btrfs_get_acl,
e41f941a 8779 .update_time = btrfs_update_time,
39279cc3 8780};
76dda93c 8781
82d339d9 8782const struct dentry_operations btrfs_dentry_operations = {
76dda93c 8783 .d_delete = btrfs_dentry_delete,
b4aff1f8 8784 .d_release = btrfs_dentry_release,
76dda93c 8785};
Linux 6.x block layer and io_uring tree(s)