fs/btrfs/disk-io.c

   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
  19 #include <linux/fs.h>
  20 #include <linux/blkdev.h>
  21 #include <linux/crc32c.h>
  22 #include <linux/scatterlist.h>
  23 #include <linux/swap.h>
  24 #include <linux/radix-tree.h>
  25 #include <linux/writeback.h>
  26 #include <linux/buffer_head.h> // for block_sync_page
  27 #include "ctree.h"
  28 #include "disk-io.h"
  29 #include "transaction.h"
  30 #include "btrfs_inode.h"
  31 #include "print-tree.h"
  32
  33 #if 0
  34 static int check_tree_block(struct btrfs_root *root, struct extent_buffer *buf)
  35 {
  36         if (extent_buffer_blocknr(buf) != btrfs_header_blocknr(buf)) {
  37                 printk(KERN_CRIT "buf blocknr(buf) is %llu, header is %llu\n",
  38                        (unsigned long long)extent_buffer_blocknr(buf),
  39                        (unsigned long long)btrfs_header_blocknr(buf));
  40                 return 1;
  41         }
  42         return 0;
  43 }
  44 #endif
  45
  46 struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root,
  47                                             u64 bytenr, u32 blocksize)
  48 {
  49         struct inode *btree_inode = root->fs_info->btree_inode;
  50         struct extent_buffer *eb;
  51         eb = find_extent_buffer(&BTRFS_I(btree_inode)->extent_tree,
  52                                 bytenr, blocksize, GFP_NOFS);
  53         return eb;
  54 }
  55
  56 struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
  57                                                  u64 bytenr, u32 blocksize)
  58 {
  59         struct inode *btree_inode = root->fs_info->btree_inode;
  60         struct extent_buffer *eb;
  61
  62         eb = alloc_extent_buffer(&BTRFS_I(btree_inode)->extent_tree,
  63                                  bytenr, blocksize, NULL, GFP_NOFS);
  64         return eb;
  65 }
  66
  67 struct extent_map *btree_get_extent(struct inode *inode, struct page *page,
  68                                     size_t page_offset, u64 start, u64 end,
  69                                     int create)
  70 {
  71         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
  72         struct extent_map *em;
  73         int ret;
  74
  75 again:
  76         em = lookup_extent_mapping(em_tree, start, end);
  77         if (em) {
  78                 goto out;
  79         }
  80         em = alloc_extent_map(GFP_NOFS);
  81         if (!em) {
  82                 em = ERR_PTR(-ENOMEM);
  83                 goto out;
  84         }
  85         em->start = 0;
  86         em->end = (i_size_read(inode) & ~((u64)PAGE_CACHE_SIZE -1)) - 1;
  87         em->block_start = 0;
  88         em->block_end = em->end;
  89         em->bdev = inode->i_sb->s_bdev;
  90         ret = add_extent_mapping(em_tree, em);
  91         if (ret == -EEXIST) {
  92                 free_extent_map(em);
  93                 em = NULL;
  94                 goto again;
  95         } else if (ret) {
  96                 em = ERR_PTR(ret);
  97         }
  98 out:
  99         return em;
 100 }
 101
 102 u32 btrfs_csum_data(struct btrfs_root *root, char *data, u32 seed, size_t len)
 103 {
 104         return crc32c(seed, data, len);
 105 }
 106
 107 void btrfs_csum_final(u32 crc, char *result)
 108 {
 109         *(__le32 *)result = ~cpu_to_le32(crc);
 110 }
 111
 112 static int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf,
 113                            int verify)
 114 {
 115         char result[BTRFS_CRC32_SIZE];
 116         unsigned long len;
 117         unsigned long cur_len;
 118         unsigned long offset = BTRFS_CSUM_SIZE;
 119         char *map_token = NULL;
 120         char *kaddr;
 121         unsigned long map_start;
 122         unsigned long map_len;
 123         int err;
 124         u32 crc = ~(u32)0;
 125
 126         len = buf->len - offset;
 127         while(len > 0) {
 128                 err = map_private_extent_buffer(buf, offset, 32,
 129                                         &map_token, &kaddr,
 130                                         &map_start, &map_len, KM_USER0);
 131                 if (err) {
 132                         printk("failed to map extent buffer! %lu\n",
 133                                offset);
 134                         return 1;
 135                 }
 136                 cur_len = min(len, map_len - (offset - map_start));
 137                 crc = btrfs_csum_data(root, kaddr + offset - map_start,
 138                                       crc, cur_len);
 139                 len -= cur_len;
 140                 offset += cur_len;
 141                 unmap_extent_buffer(buf, map_token, KM_USER0);
 142         }
 143         btrfs_csum_final(crc, result);
 144
 145         if (verify) {
 146                 if (memcmp_extent_buffer(buf, result, 0, BTRFS_CRC32_SIZE)) {
 147                         printk("btrfs: %s checksum verify failed on %llu\n",
 148                                root->fs_info->sb->s_id,
 149                                buf->start);
 150                         return 1;
 151                 }
 152         } else {
 153                 write_extent_buffer(buf, result, 0, BTRFS_CRC32_SIZE);
 154         }
 155         return 0;
 156 }
 157
 158
 159 int csum_dirty_buffer(struct btrfs_root *root, struct page *page)
 160 {
 161         struct extent_map_tree *tree;
 162         u64 start = page->index << PAGE_CACHE_SHIFT;
 163         u64 found_start;
 164         int found_level;
 165         unsigned long len;
 166         struct extent_buffer *eb;
 167         tree = &BTRFS_I(page->mapping->host)->extent_tree;
 168
 169         if (page->private == EXTENT_PAGE_PRIVATE)
 170                 goto out;
 171         if (!page->private)
 172                 goto out;
 173         len = page->private >> 2;
 174         if (len == 0) {
 175                 WARN_ON(1);
 176         }
 177         eb = alloc_extent_buffer(tree, start, len, page, GFP_NOFS);
 178         read_extent_buffer_pages(tree, eb, start + PAGE_CACHE_SIZE, 1);
 179         found_start = btrfs_header_bytenr(eb);
 180         if (found_start != start) {
 181                 printk("warning: eb start incorrect %Lu buffer %Lu len %lu\n",
 182                        start, found_start, len);
 183         }
 184         found_level = btrfs_header_level(eb);
 185         csum_tree_block(root, eb, 0);
 186         free_extent_buffer(eb);
 187 out:
 188         return 0;
 189 }
 190
 191 static int btree_writepage(struct page *page, struct writeback_control *wbc)
 192 {
 193         struct extent_map_tree *tree;
 194         struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
 195         tree = &BTRFS_I(page->mapping->host)->extent_tree;
 196
 197         csum_dirty_buffer(root, page);
 198         return extent_write_full_page(tree, page, btree_get_extent, wbc);
 199 }
 200 int btree_readpage(struct file *file, struct page *page)
 201 {
 202         struct extent_map_tree *tree;
 203         tree = &BTRFS_I(page->mapping->host)->extent_tree;
 204         return extent_read_full_page(tree, page, btree_get_extent);
 205 }
 206
 207 static int btree_releasepage(struct page *page, gfp_t unused_gfp_flags)
 208 {
 209         struct extent_map_tree *tree;
 210         int ret;
 211
 212         tree = &BTRFS_I(page->mapping->host)->extent_tree;
 213         ret = try_release_extent_mapping(tree, page);
 214         if (ret == 1) {
 215                 ClearPagePrivate(page);
 216                 set_page_private(page, 0);
 217                 page_cache_release(page);
 218         }
 219         return ret;
 220 }
 221
 222 static void btree_invalidatepage(struct page *page, unsigned long offset)
 223 {
 224         struct extent_map_tree *tree;
 225         tree = &BTRFS_I(page->mapping->host)->extent_tree;
 226         extent_invalidatepage(tree, page, offset);
 227         btree_releasepage(page, GFP_NOFS);
 228 }
 229
 230 #if 0
 231 static int btree_writepage(struct page *page, struct writeback_control *wbc)
 232 {
 233         struct buffer_head *bh;
 234         struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
 235         struct buffer_head *head;
 236         if (!page_has_buffers(page)) {
 237                 create_empty_buffers(page, root->fs_info->sb->s_blocksize,
 238                                         (1 << BH_Dirty)|(1 << BH_Uptodate));
 239         }
 240         head = page_buffers(page);
 241         bh = head;
 242         do {
 243                 if (buffer_dirty(bh))
 244                         csum_tree_block(root, bh, 0);
 245                 bh = bh->b_this_page;
 246         } while (bh != head);
 247         return block_write_full_page(page, btree_get_block, wbc);
 248 }
 249 #endif
 250
 251 static struct address_space_operations btree_aops = {
 252         .readpage       = btree_readpage,
 253         .writepage      = btree_writepage,
 254         .releasepage    = btree_releasepage,
 255         .invalidatepage = btree_invalidatepage,
 256         .sync_page      = block_sync_page,
 257 };
 258
 259 int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize)
 260 {
 261         struct extent_buffer *buf = NULL;
 262         struct inode *btree_inode = root->fs_info->btree_inode;
 263         int ret = 0;
 264
 265         buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
 266         if (!buf)
 267                 return 0;
 268         read_extent_buffer_pages(&BTRFS_I(btree_inode)->extent_tree,
 269                                  buf, 0, 0);
 270         free_extent_buffer(buf);
 271         return ret;
 272 }
 273
 274 struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
 275                                       u32 blocksize)
 276 {
 277         struct extent_buffer *buf = NULL;
 278         struct inode *btree_inode = root->fs_info->btree_inode;
 279         struct extent_map_tree *extent_tree;
 280         int ret;
 281
 282         extent_tree = &BTRFS_I(btree_inode)->extent_tree;
 283
 284         buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
 285         if (!buf)
 286                 return NULL;
 287         read_extent_buffer_pages(&BTRFS_I(btree_inode)->extent_tree,
 288                                  buf, 0, 1);
 289         if (buf->flags & EXTENT_CSUM) {
 290                 return buf;
 291         }
 292         if (test_range_bit(extent_tree, buf->start, buf->start + buf->len - 1,
 293                            EXTENT_CSUM, 1)) {
 294                 buf->flags |= EXTENT_CSUM;
 295                 return buf;
 296         }
 297         ret = csum_tree_block(root, buf, 1);
 298         set_extent_bits(extent_tree, buf->start,
 299                         buf->start + buf->len - 1,
 300                         EXTENT_CSUM, GFP_NOFS);
 301         buf->flags |= EXTENT_CSUM;
 302         return buf;
 303 }
 304
 305 int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 306                      struct extent_buffer *buf)
 307 {
 308         struct inode *btree_inode = root->fs_info->btree_inode;
 309         clear_extent_buffer_dirty(&BTRFS_I(btree_inode)->extent_tree, buf);
 310         return 0;
 311 }
 312
 313 int wait_on_tree_block_writeback(struct btrfs_root *root,
 314                                  struct extent_buffer *buf)
 315 {
 316         struct inode *btree_inode = root->fs_info->btree_inode;
 317         wait_on_extent_buffer_writeback(&BTRFS_I(btree_inode)->extent_tree,
 318                                         buf);
 319         return 0;
 320 }
 321
 322 static int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
 323                         struct btrfs_root *root,
 324                         struct btrfs_fs_info *fs_info,
 325                         u64 objectid)
 326 {
 327         root->node = NULL;
 328         root->inode = NULL;
 329         root->commit_root = NULL;
 330         root->sectorsize = sectorsize;
 331         root->nodesize = nodesize;
 332         root->leafsize = leafsize;
 333         root->ref_cows = 0;
 334         root->fs_info = fs_info;
 335         root->objectid = objectid;
 336         root->last_trans = 0;
 337         root->highest_inode = 0;
 338         root->last_inode_alloc = 0;
 339         root->name = NULL;
 340         memset(&root->root_key, 0, sizeof(root->root_key));
 341         memset(&root->root_item, 0, sizeof(root->root_item));
 342         memset(&root->defrag_progress, 0, sizeof(root->defrag_progress));
 343         memset(&root->root_kobj, 0, sizeof(root->root_kobj));
 344         init_completion(&root->kobj_unregister);
 345         init_rwsem(&root->snap_sem);
 346         root->defrag_running = 0;
 347         root->defrag_level = 0;
 348         root->root_key.objectid = objectid;
 349         return 0;
 350 }
 351
 352 static int find_and_setup_root(struct btrfs_root *tree_root,
 353                                struct btrfs_fs_info *fs_info,
 354                                u64 objectid,
 355                                struct btrfs_root *root)
 356 {
 357         int ret;
 358         u32 blocksize;
 359
 360         __setup_root(tree_root->nodesize, tree_root->leafsize,
 361                      tree_root->sectorsize, root, fs_info, objectid);
 362         ret = btrfs_find_last_root(tree_root, objectid,
 363                                    &root->root_item, &root->root_key);
 364         BUG_ON(ret);
 365
 366         blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
 367         root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
 368                                      blocksize);
 369         BUG_ON(!root->node);
 370         return 0;
 371 }
 372
 373 struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_fs_info *fs_info,
 374                                                struct btrfs_key *location)
 375 {
 376         struct btrfs_root *root;
 377         struct btrfs_root *tree_root = fs_info->tree_root;
 378         struct btrfs_path *path;
 379         struct extent_buffer *l;
 380         u64 highest_inode;
 381         u32 blocksize;
 382         int ret = 0;
 383
 384         root = kzalloc(sizeof(*root), GFP_NOFS);
 385         if (!root)
 386                 return ERR_PTR(-ENOMEM);
 387         if (location->offset == (u64)-1) {
 388                 ret = find_and_setup_root(tree_root, fs_info,
 389                                           location->objectid, root);
 390                 if (ret) {
 391                         kfree(root);
 392                         return ERR_PTR(ret);
 393                 }
 394                 goto insert;
 395         }
 396
 397         __setup_root(tree_root->nodesize, tree_root->leafsize,
 398                      tree_root->sectorsize, root, fs_info,
 399                      location->objectid);
 400
 401         path = btrfs_alloc_path();
 402         BUG_ON(!path);
 403         ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0);
 404         if (ret != 0) {
 405                 if (ret > 0)
 406                         ret = -ENOENT;
 407                 goto out;
 408         }
 409         l = path->nodes[0];
 410         read_extent_buffer(l, &root->root_item,
 411                btrfs_item_ptr_offset(l, path->slots[0]),
 412                sizeof(root->root_item));
 413         memcpy(&root->root_key, location, sizeof(*location));
 414         ret = 0;
 415 out:
 416         btrfs_release_path(root, path);
 417         btrfs_free_path(path);
 418         if (ret) {
 419                 kfree(root);
 420                 return ERR_PTR(ret);
 421         }
 422         blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
 423         root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
 424                                      blocksize);
 425         BUG_ON(!root->node);
 426 insert:
 427         root->ref_cows = 1;
 428         ret = btrfs_find_highest_inode(root, &highest_inode);
 429         if (ret == 0) {
 430                 root->highest_inode = highest_inode;
 431                 root->last_inode_alloc = highest_inode;
 432         }
 433         return root;
 434 }
 435
 436 struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
 437                                       struct btrfs_key *location,
 438                                       const char *name, int namelen)
 439 {
 440         struct btrfs_root *root;
 441         int ret;
 442
 443         root = radix_tree_lookup(&fs_info->fs_roots_radix,
 444                                  (unsigned long)location->objectid);
 445         if (root)
 446                 return root;
 447
 448         root = btrfs_read_fs_root_no_radix(fs_info, location);
 449         if (IS_ERR(root))
 450                 return root;
 451         ret = radix_tree_insert(&fs_info->fs_roots_radix,
 452                                 (unsigned long)root->root_key.objectid,
 453                                 root);
 454         if (ret) {
 455                 free_extent_buffer(root->node);
 456                 kfree(root);
 457                 return ERR_PTR(ret);
 458         }
 459
 460         ret = btrfs_set_root_name(root, name, namelen);
 461         if (ret) {
 462                 free_extent_buffer(root->node);
 463                 kfree(root);
 464                 return ERR_PTR(ret);
 465         }
 466
 467         ret = btrfs_sysfs_add_root(root);
 468         if (ret) {
 469                 free_extent_buffer(root->node);
 470                 kfree(root->name);
 471                 kfree(root);
 472                 return ERR_PTR(ret);
 473         }
 474
 475         ret = btrfs_find_dead_roots(fs_info->tree_root,
 476                                     root->root_key.objectid, root);
 477         BUG_ON(ret);
 478
 479         return root;
 480 }
 481 #if 0
 482 static int add_hasher(struct btrfs_fs_info *info, char *type) {
 483         struct btrfs_hasher *hasher;
 484
 485         hasher = kmalloc(sizeof(*hasher), GFP_NOFS);
 486         if (!hasher)
 487                 return -ENOMEM;
 488         hasher->hash_tfm = crypto_alloc_hash(type, 0, CRYPTO_ALG_ASYNC);
 489         if (!hasher->hash_tfm) {
 490                 kfree(hasher);
 491                 return -EINVAL;
 492         }
 493         spin_lock(&info->hash_lock);
 494         list_add(&hasher->list, &info->hashers);
 495         spin_unlock(&info->hash_lock);
 496         return 0;
 497 }
 498 #endif
 499 struct btrfs_root *open_ctree(struct super_block *sb)
 500 {
 501         u32 sectorsize;
 502         u32 nodesize;
 503         u32 leafsize;
 504         u32 blocksize;
 505         struct btrfs_root *extent_root = kmalloc(sizeof(struct btrfs_root),
 506                                                  GFP_NOFS);
 507         struct btrfs_root *tree_root = kmalloc(sizeof(struct btrfs_root),
 508                                                GFP_NOFS);
 509         struct btrfs_fs_info *fs_info = kmalloc(sizeof(*fs_info),
 510                                                 GFP_NOFS);
 511         int ret;
 512         int err = -EIO;
 513         struct btrfs_super_block *disk_super;
 514
 515         if (!extent_root || !tree_root || !fs_info) {
 516                 err = -ENOMEM;
 517                 goto fail;
 518         }
 519         INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_NOFS);
 520         INIT_LIST_HEAD(&fs_info->trans_list);
 521         INIT_LIST_HEAD(&fs_info->dead_roots);
 522         INIT_LIST_HEAD(&fs_info->hashers);
 523         spin_lock_init(&fs_info->hash_lock);
 524
 525         memset(&fs_info->super_kobj, 0, sizeof(fs_info->super_kobj));
 526         init_completion(&fs_info->kobj_unregister);
 527         sb_set_blocksize(sb, 4096);
 528         fs_info->running_transaction = NULL;
 529         fs_info->last_trans_committed = 0;
 530         fs_info->tree_root = tree_root;
 531         fs_info->extent_root = extent_root;
 532         fs_info->sb = sb;
 533         fs_info->btree_inode = new_inode(sb);
 534         fs_info->btree_inode->i_ino = 1;
 535         fs_info->btree_inode->i_nlink = 1;
 536         fs_info->btree_inode->i_size = sb->s_bdev->bd_inode->i_size;
 537         fs_info->btree_inode->i_mapping->a_ops = &btree_aops;
 538         extent_map_tree_init(&BTRFS_I(fs_info->btree_inode)->extent_tree,
 539                              fs_info->btree_inode->i_mapping,
 540                              GFP_NOFS);
 541         extent_map_tree_init(&fs_info->free_space_cache,
 542                              fs_info->btree_inode->i_mapping, GFP_NOFS);
 543         extent_map_tree_init(&fs_info->block_group_cache,
 544                              fs_info->btree_inode->i_mapping, GFP_NOFS);
 545         extent_map_tree_init(&fs_info->pinned_extents,
 546                              fs_info->btree_inode->i_mapping, GFP_NOFS);
 547         extent_map_tree_init(&fs_info->pending_del,
 548                              fs_info->btree_inode->i_mapping, GFP_NOFS);
 549         extent_map_tree_init(&fs_info->extent_ins,
 550                              fs_info->btree_inode->i_mapping, GFP_NOFS);
 551         fs_info->do_barriers = 1;
 552         fs_info->closing = 0;
 553
 554         INIT_DELAYED_WORK(&fs_info->trans_work, btrfs_transaction_cleaner);
 555         BTRFS_I(fs_info->btree_inode)->root = tree_root;
 556         memset(&BTRFS_I(fs_info->btree_inode)->location, 0,
 557                sizeof(struct btrfs_key));
 558         insert_inode_hash(fs_info->btree_inode);
 559         mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS);
 560
 561         mutex_init(&fs_info->trans_mutex);
 562         mutex_init(&fs_info->fs_mutex);
 563
 564 #if 0
 565         ret = add_hasher(fs_info, "crc32c");
 566         if (ret) {
 567                 printk("btrfs: failed hash setup, modprobe cryptomgr?\n");
 568                 err = -ENOMEM;
 569                 goto fail_iput;
 570         }
 571 #endif
 572         __setup_root(512, 512, 512, tree_root,
 573                      fs_info, BTRFS_ROOT_TREE_OBJECTID);
 574
 575         fs_info->sb_buffer = read_tree_block(tree_root,
 576                                              BTRFS_SUPER_INFO_OFFSET,
 577                                              512);
 578
 579         if (!fs_info->sb_buffer)
 580                 goto fail_iput;
 581
 582         read_extent_buffer(fs_info->sb_buffer, &fs_info->super_copy, 0,
 583                            sizeof(fs_info->super_copy));
 584
 585         read_extent_buffer(fs_info->sb_buffer, fs_info->fsid,
 586                            (unsigned long)btrfs_super_fsid(fs_info->sb_buffer),
 587                            BTRFS_FSID_SIZE);
 588         disk_super = &fs_info->super_copy;
 589         if (!btrfs_super_root(disk_super))
 590                 goto fail_sb_buffer;
 591
 592         nodesize = btrfs_super_nodesize(disk_super);
 593         leafsize = btrfs_super_leafsize(disk_super);
 594         sectorsize = btrfs_super_sectorsize(disk_super);
 595         tree_root->nodesize = nodesize;
 596         tree_root->leafsize = leafsize;
 597         tree_root->sectorsize = sectorsize;
 598         sb_set_blocksize(sb, sectorsize);
 599
 600         i_size_write(fs_info->btree_inode,
 601                      btrfs_super_total_bytes(disk_super));
 602
 603         if (strncmp((char *)(&disk_super->magic), BTRFS_MAGIC,
 604                     sizeof(disk_super->magic))) {
 605                 printk("btrfs: valid FS not found on %s\n", sb->s_id);
 606                 goto fail_sb_buffer;
 607         }
 608
 609         blocksize = btrfs_level_size(tree_root,
 610                                      btrfs_super_root_level(disk_super));
 611
 612         tree_root->node = read_tree_block(tree_root,
 613                                           btrfs_super_root(disk_super),
 614                                           blocksize);
 615         if (!tree_root->node)
 616                 goto fail_sb_buffer;
 617
 618         mutex_lock(&fs_info->fs_mutex);
 619
 620         ret = find_and_setup_root(tree_root, fs_info,
 621                                   BTRFS_EXTENT_TREE_OBJECTID, extent_root);
 622         if (ret) {
 623                 mutex_unlock(&fs_info->fs_mutex);
 624                 goto fail_tree_root;
 625         }
 626
 627         btrfs_read_block_groups(extent_root);
 628
 629         fs_info->generation = btrfs_super_generation(disk_super) + 1;
 630         mutex_unlock(&fs_info->fs_mutex);
 631         return tree_root;
 632
 633 fail_tree_root:
 634         free_extent_buffer(tree_root->node);
 635 fail_sb_buffer:
 636         free_extent_buffer(fs_info->sb_buffer);
 637 fail_iput:
 638         iput(fs_info->btree_inode);
 639 fail:
 640         kfree(extent_root);
 641         kfree(tree_root);
 642         kfree(fs_info);
 643         return ERR_PTR(err);
 644 }
 645
 646 int write_ctree_super(struct btrfs_trans_handle *trans, struct btrfs_root
 647                       *root)
 648 {
 649         int ret;
 650         struct extent_buffer *super = root->fs_info->sb_buffer;
 651         struct inode *btree_inode = root->fs_info->btree_inode;
 652
 653         set_extent_buffer_dirty(&BTRFS_I(btree_inode)->extent_tree, super);
 654         ret = sync_page_range_nolock(btree_inode, btree_inode->i_mapping,
 655                                      super->start, super->len);
 656         return ret;
 657 }
 658
 659 int btrfs_free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root)
 660 {
 661         radix_tree_delete(&fs_info->fs_roots_radix,
 662                           (unsigned long)root->root_key.objectid);
 663         btrfs_sysfs_del_root(root);
 664         if (root->inode)
 665                 iput(root->inode);
 666         if (root->node)
 667                 free_extent_buffer(root->node);
 668         if (root->commit_root)
 669                 free_extent_buffer(root->commit_root);
 670         if (root->name)
 671                 kfree(root->name);
 672         kfree(root);
 673         return 0;
 674 }
 675
 676 static int del_fs_roots(struct btrfs_fs_info *fs_info)
 677 {
 678         int ret;
 679         struct btrfs_root *gang[8];
 680         int i;
 681
 682         while(1) {
 683                 ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
 684                                              (void **)gang, 0,
 685                                              ARRAY_SIZE(gang));
 686                 if (!ret)
 687                         break;
 688                 for (i = 0; i < ret; i++)
 689                         btrfs_free_fs_root(fs_info, gang[i]);
 690         }
 691         return 0;
 692 }
 693
 694 int close_ctree(struct btrfs_root *root)
 695 {
 696         int ret;
 697         struct btrfs_trans_handle *trans;
 698         struct btrfs_fs_info *fs_info = root->fs_info;
 699
 700         fs_info->closing = 1;
 701         btrfs_transaction_flush_work(root);
 702         mutex_lock(&fs_info->fs_mutex);
 703         btrfs_defrag_dirty_roots(root->fs_info);
 704         trans = btrfs_start_transaction(root, 1);
 705         ret = btrfs_commit_transaction(trans, root);
 706         /* run commit again to  drop the original snapshot */
 707         trans = btrfs_start_transaction(root, 1);
 708         btrfs_commit_transaction(trans, root);
 709         ret = btrfs_write_and_wait_transaction(NULL, root);
 710         BUG_ON(ret);
 711         write_ctree_super(NULL, root);
 712         mutex_unlock(&fs_info->fs_mutex);
 713
 714         if (fs_info->extent_root->node)
 715                 free_extent_buffer(fs_info->extent_root->node);
 716
 717         if (fs_info->tree_root->node)
 718                 free_extent_buffer(fs_info->tree_root->node);
 719
 720         free_extent_buffer(fs_info->sb_buffer);
 721
 722         btrfs_free_block_groups(root->fs_info);
 723         del_fs_roots(fs_info);
 724         extent_map_tree_empty_lru(&BTRFS_I(fs_info->btree_inode)->extent_tree);
 725         truncate_inode_pages(fs_info->btree_inode->i_mapping, 0);
 726         iput(fs_info->btree_inode);
 727 #if 0
 728         while(!list_empty(&fs_info->hashers)) {
 729                 struct btrfs_hasher *hasher;
 730                 hasher = list_entry(fs_info->hashers.next, struct btrfs_hasher,
 731                                     hashers);
 732                 list_del(&hasher->hashers);
 733                 crypto_free_hash(&fs_info->hash_tfm);
 734                 kfree(hasher);
 735         }
 736 #endif
 737         kfree(fs_info->extent_root);
 738         kfree(fs_info->tree_root);
 739         return 0;
 740 }
 741
 742 int btrfs_buffer_uptodate(struct extent_buffer *buf)
 743 {
 744         struct inode *btree_inode = buf->first_page->mapping->host;
 745         return extent_buffer_uptodate(&BTRFS_I(btree_inode)->extent_tree, buf);
 746 }
 747
 748 int btrfs_set_buffer_uptodate(struct extent_buffer *buf)
 749 {
 750         struct inode *btree_inode = buf->first_page->mapping->host;
 751         return set_extent_buffer_uptodate(&BTRFS_I(btree_inode)->extent_tree,
 752                                           buf);
 753 }
 754
 755 void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
 756 {
 757         struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
 758         u64 transid = btrfs_header_generation(buf);
 759         struct inode *btree_inode = root->fs_info->btree_inode;
 760
 761         if (transid != root->fs_info->generation) {
 762                 printk(KERN_CRIT "transid mismatch buffer %llu, found %Lu running %Lu\n",
 763                         (unsigned long long)buf->start,
 764                         transid, root->fs_info->generation);
 765                 WARN_ON(1);
 766         }
 767         set_extent_buffer_dirty(&BTRFS_I(btree_inode)->extent_tree, buf);
 768 }
 769
 770 void btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr)
 771 {
 772         balance_dirty_pages_ratelimited_nr(
 773                         root->fs_info->btree_inode->i_mapping, 1);
 774 }
 775
 776 void btrfs_set_buffer_defrag(struct extent_buffer *buf)
 777 {
 778         struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
 779         struct inode *btree_inode = root->fs_info->btree_inode;
 780         set_extent_bits(&BTRFS_I(btree_inode)->extent_tree, buf->start,
 781                         buf->start + buf->len - 1, EXTENT_DEFRAG, GFP_NOFS);
 782 }
 783
 784 void btrfs_set_buffer_defrag_done(struct extent_buffer *buf)
 785 {
 786         struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
 787         struct inode *btree_inode = root->fs_info->btree_inode;
 788         set_extent_bits(&BTRFS_I(btree_inode)->extent_tree, buf->start,
 789                         buf->start + buf->len - 1, EXTENT_DEFRAG_DONE,
 790                         GFP_NOFS);
 791 }
 792
 793 int btrfs_buffer_defrag(struct extent_buffer *buf)
 794 {
 795         struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
 796         struct inode *btree_inode = root->fs_info->btree_inode;
 797         return test_range_bit(&BTRFS_I(btree_inode)->extent_tree,
 798                      buf->start, buf->start + buf->len - 1, EXTENT_DEFRAG, 0);
 799 }
 800
 801 int btrfs_buffer_defrag_done(struct extent_buffer *buf)
 802 {
 803         struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
 804         struct inode *btree_inode = root->fs_info->btree_inode;
 805         return test_range_bit(&BTRFS_I(btree_inode)->extent_tree,
 806                      buf->start, buf->start + buf->len - 1,
 807                      EXTENT_DEFRAG_DONE, 0);
 808 }
 809
 810 int btrfs_clear_buffer_defrag_done(struct extent_buffer *buf)
 811 {
 812         struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
 813         struct inode *btree_inode = root->fs_info->btree_inode;
 814         return clear_extent_bits(&BTRFS_I(btree_inode)->extent_tree,
 815                      buf->start, buf->start + buf->len - 1,
 816                      EXTENT_DEFRAG_DONE, GFP_NOFS);
 817 }
 818
 819 int btrfs_clear_buffer_defrag(struct extent_buffer *buf)
 820 {
 821         struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
 822         struct inode *btree_inode = root->fs_info->btree_inode;
 823         return clear_extent_bits(&BTRFS_I(btree_inode)->extent_tree,
 824                      buf->start, buf->start + buf->len - 1,
 825                      EXTENT_DEFRAG, GFP_NOFS);
 826 }
 827
 828 int btrfs_read_buffer(struct extent_buffer *buf)
 829 {
 830         struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
 831         struct inode *btree_inode = root->fs_info->btree_inode;
 832         return read_extent_buffer_pages(&BTRFS_I(btree_inode)->extent_tree,
 833                                         buf, 0, 1);
 834 }