fs/btrfs/ordered-data.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 2007 Oracle.  All rights reserved.
   4  */
   5
   6 #include <linux/slab.h>
   7 #include <linux/blkdev.h>
   8 #include <linux/writeback.h>
   9 #include <linux/sched/mm.h>
  10 #include "messages.h"
  11 #include "misc.h"
  12 #include "ctree.h"
  13 #include "transaction.h"
  14 #include "btrfs_inode.h"
  15 #include "extent_io.h"
  16 #include "disk-io.h"
  17 #include "compression.h"
  18 #include "delalloc-space.h"
  19 #include "qgroup.h"
  20 #include "subpage.h"
  21 #include "file.h"
  22 #include "super.h"
  23
  24 static struct kmem_cache *btrfs_ordered_extent_cache;
  25
  26 static u64 entry_end(struct btrfs_ordered_extent *entry)
  27 {
  28         if (entry->file_offset + entry->num_bytes < entry->file_offset)
  29                 return (u64)-1;
  30         return entry->file_offset + entry->num_bytes;
  31 }
  32
  33 /* returns NULL if the insertion worked, or it returns the node it did find
  34  * in the tree
  35  */
  36 static struct rb_node *tree_insert(struct rb_root *root, u64 file_offset,
  37                                    struct rb_node *node)
  38 {
  39         struct rb_node **p = &root->rb_node;
  40         struct rb_node *parent = NULL;
  41         struct btrfs_ordered_extent *entry;
  42
  43         while (*p) {
  44                 parent = *p;
  45                 entry = rb_entry(parent, struct btrfs_ordered_extent, rb_node);
  46
  47                 if (file_offset < entry->file_offset)
  48                         p = &(*p)->rb_left;
  49                 else if (file_offset >= entry_end(entry))
  50                         p = &(*p)->rb_right;
  51                 else
  52                         return parent;
  53         }
  54
  55         rb_link_node(node, parent, p);
  56         rb_insert_color(node, root);
  57         return NULL;
  58 }
  59
  60 /*
  61  * look for a given offset in the tree, and if it can't be found return the
  62  * first lesser offset
  63  */
  64 static struct rb_node *__tree_search(struct rb_root *root, u64 file_offset,
  65                                      struct rb_node **prev_ret)
  66 {
  67         struct rb_node *n = root->rb_node;
  68         struct rb_node *prev = NULL;
  69         struct rb_node *test;
  70         struct btrfs_ordered_extent *entry;
  71         struct btrfs_ordered_extent *prev_entry = NULL;
  72
  73         while (n) {
  74                 entry = rb_entry(n, struct btrfs_ordered_extent, rb_node);
  75                 prev = n;
  76                 prev_entry = entry;
  77
  78                 if (file_offset < entry->file_offset)
  79                         n = n->rb_left;
  80                 else if (file_offset >= entry_end(entry))
  81                         n = n->rb_right;
  82                 else
  83                         return n;
  84         }
  85         if (!prev_ret)
  86                 return NULL;
  87
  88         while (prev && file_offset >= entry_end(prev_entry)) {
  89                 test = rb_next(prev);
  90                 if (!test)
  91                         break;
  92                 prev_entry = rb_entry(test, struct btrfs_ordered_extent,
  93                                       rb_node);
  94                 if (file_offset < entry_end(prev_entry))
  95                         break;
  96
  97                 prev = test;
  98         }
  99         if (prev)
 100                 prev_entry = rb_entry(prev, struct btrfs_ordered_extent,
 101                                       rb_node);
 102         while (prev && file_offset < entry_end(prev_entry)) {
 103                 test = rb_prev(prev);
 104                 if (!test)
 105                         break;
 106                 prev_entry = rb_entry(test, struct btrfs_ordered_extent,
 107                                       rb_node);
 108                 prev = test;
 109         }
 110         *prev_ret = prev;
 111         return NULL;
 112 }
 113
 114 static int range_overlaps(struct btrfs_ordered_extent *entry, u64 file_offset,
 115                           u64 len)
 116 {
 117         if (file_offset + len <= entry->file_offset ||
 118             entry->file_offset + entry->num_bytes <= file_offset)
 119                 return 0;
 120         return 1;
 121 }
 122
 123 /*
 124  * look find the first ordered struct that has this offset, otherwise
 125  * the first one less than this offset
 126  */
 127 static inline struct rb_node *ordered_tree_search(struct btrfs_inode *inode,
 128                                                   u64 file_offset)
 129 {
 130         struct rb_node *prev = NULL;
 131         struct rb_node *ret;
 132         struct btrfs_ordered_extent *entry;
 133
 134         if (inode->ordered_tree_last) {
 135                 entry = rb_entry(inode->ordered_tree_last, struct btrfs_ordered_extent,
 136                                  rb_node);
 137                 if (in_range(file_offset, entry->file_offset, entry->num_bytes))
 138                         return inode->ordered_tree_last;
 139         }
 140         ret = __tree_search(&inode->ordered_tree, file_offset, &prev);
 141         if (!ret)
 142                 ret = prev;
 143         if (ret)
 144                 inode->ordered_tree_last = ret;
 145         return ret;
 146 }
 147
 148 static struct btrfs_ordered_extent *alloc_ordered_extent(
 149                         struct btrfs_inode *inode, u64 file_offset, u64 num_bytes,
 150                         u64 ram_bytes, u64 disk_bytenr, u64 disk_num_bytes,
 151                         u64 offset, unsigned long flags, int compress_type)
 152 {
 153         struct btrfs_ordered_extent *entry;
 154         int ret;
 155
 156         if (flags &
 157             ((1 << BTRFS_ORDERED_NOCOW) | (1 << BTRFS_ORDERED_PREALLOC))) {
 158                 /* For nocow write, we can release the qgroup rsv right now */
 159                 ret = btrfs_qgroup_free_data(inode, NULL, file_offset, num_bytes);
 160                 if (ret < 0)
 161                         return ERR_PTR(ret);
 162         } else {
 163                 /*
 164                  * The ordered extent has reserved qgroup space, release now
 165                  * and pass the reserved number for qgroup_record to free.
 166                  */
 167                 ret = btrfs_qgroup_release_data(inode, file_offset, num_bytes);
 168                 if (ret < 0)
 169                         return ERR_PTR(ret);
 170         }
 171         entry = kmem_cache_zalloc(btrfs_ordered_extent_cache, GFP_NOFS);
 172         if (!entry)
 173                 return ERR_PTR(-ENOMEM);
 174
 175         entry->file_offset = file_offset;
 176         entry->num_bytes = num_bytes;
 177         entry->ram_bytes = ram_bytes;
 178         entry->disk_bytenr = disk_bytenr;
 179         entry->disk_num_bytes = disk_num_bytes;
 180         entry->offset = offset;
 181         entry->bytes_left = num_bytes;
 182         entry->inode = igrab(&inode->vfs_inode);
 183         entry->compress_type = compress_type;
 184         entry->truncated_len = (u64)-1;
 185         entry->qgroup_rsv = ret;
 186         entry->flags = flags;
 187         refcount_set(&entry->refs, 1);
 188         init_waitqueue_head(&entry->wait);
 189         INIT_LIST_HEAD(&entry->list);
 190         INIT_LIST_HEAD(&entry->log_list);
 191         INIT_LIST_HEAD(&entry->root_extent_list);
 192         INIT_LIST_HEAD(&entry->work_list);
 193         INIT_LIST_HEAD(&entry->bioc_list);
 194         init_completion(&entry->completion);
 195
 196         /*
 197          * We don't need the count_max_extents here, we can assume that all of
 198          * that work has been done at higher layers, so this is truly the
 199          * smallest the extent is going to get.
 200          */
 201         spin_lock(&inode->lock);
 202         btrfs_mod_outstanding_extents(inode, 1);
 203         spin_unlock(&inode->lock);
 204
 205         return entry;
 206 }
 207
 208 static void insert_ordered_extent(struct btrfs_ordered_extent *entry)
 209 {
 210         struct btrfs_inode *inode = BTRFS_I(entry->inode);
 211         struct btrfs_root *root = inode->root;
 212         struct btrfs_fs_info *fs_info = root->fs_info;
 213         struct rb_node *node;
 214
 215         trace_btrfs_ordered_extent_add(inode, entry);
 216
 217         percpu_counter_add_batch(&fs_info->ordered_bytes, entry->num_bytes,
 218                                  fs_info->delalloc_batch);
 219
 220         /* One ref for the tree. */
 221         refcount_inc(&entry->refs);
 222
 223         spin_lock_irq(&inode->ordered_tree_lock);
 224         node = tree_insert(&inode->ordered_tree, entry->file_offset,
 225                            &entry->rb_node);
 226         if (node)
 227                 btrfs_panic(fs_info, -EEXIST,
 228                                 "inconsistency in ordered tree at offset %llu",
 229                                 entry->file_offset);
 230         spin_unlock_irq(&inode->ordered_tree_lock);
 231
 232         spin_lock(&root->ordered_extent_lock);
 233         list_add_tail(&entry->root_extent_list,
 234                       &root->ordered_extents);
 235         root->nr_ordered_extents++;
 236         if (root->nr_ordered_extents == 1) {
 237                 spin_lock(&fs_info->ordered_root_lock);
 238                 BUG_ON(!list_empty(&root->ordered_root));
 239                 list_add_tail(&root->ordered_root, &fs_info->ordered_roots);
 240                 spin_unlock(&fs_info->ordered_root_lock);
 241         }
 242         spin_unlock(&root->ordered_extent_lock);
 243 }
 244
 245 /*
 246  * Add an ordered extent to the per-inode tree.
 247  *
 248  * @inode:           Inode that this extent is for.
 249  * @file_offset:     Logical offset in file where the extent starts.
 250  * @num_bytes:       Logical length of extent in file.
 251  * @ram_bytes:       Full length of unencoded data.
 252  * @disk_bytenr:     Offset of extent on disk.
 253  * @disk_num_bytes:  Size of extent on disk.
 254  * @offset:          Offset into unencoded data where file data starts.
 255  * @flags:           Flags specifying type of extent (1 << BTRFS_ORDERED_*).
 256  * @compress_type:   Compression algorithm used for data.
 257  *
 258  * Most of these parameters correspond to &struct btrfs_file_extent_item. The
 259  * tree is given a single reference on the ordered extent that was inserted, and
 260  * the returned pointer is given a second reference.
 261  *
 262  * Return: the new ordered extent or error pointer.
 263  */
 264 struct btrfs_ordered_extent *btrfs_alloc_ordered_extent(
 265                         struct btrfs_inode *inode, u64 file_offset,
 266                         u64 num_bytes, u64 ram_bytes, u64 disk_bytenr,
 267                         u64 disk_num_bytes, u64 offset, unsigned long flags,
 268                         int compress_type)
 269 {
 270         struct btrfs_ordered_extent *entry;
 271
 272         ASSERT((flags & ~BTRFS_ORDERED_TYPE_FLAGS) == 0);
 273
 274         entry = alloc_ordered_extent(inode, file_offset, num_bytes, ram_bytes,
 275                                      disk_bytenr, disk_num_bytes, offset, flags,
 276                                      compress_type);
 277         if (!IS_ERR(entry))
 278                 insert_ordered_extent(entry);
 279         return entry;
 280 }
 281
 282 /*
 283  * Add a struct btrfs_ordered_sum into the list of checksums to be inserted
 284  * when an ordered extent is finished.  If the list covers more than one
 285  * ordered extent, it is split across multiples.
 286  */
 287 void btrfs_add_ordered_sum(struct btrfs_ordered_extent *entry,
 288                            struct btrfs_ordered_sum *sum)
 289 {
 290         struct btrfs_inode *inode = BTRFS_I(entry->inode);
 291
 292         spin_lock_irq(&inode->ordered_tree_lock);
 293         list_add_tail(&sum->list, &entry->list);
 294         spin_unlock_irq(&inode->ordered_tree_lock);
 295 }
 296
 297 static void finish_ordered_fn(struct btrfs_work *work)
 298 {
 299         struct btrfs_ordered_extent *ordered_extent;
 300
 301         ordered_extent = container_of(work, struct btrfs_ordered_extent, work);
 302         btrfs_finish_ordered_io(ordered_extent);
 303 }
 304
 305 static bool can_finish_ordered_extent(struct btrfs_ordered_extent *ordered,
 306                                       struct page *page, u64 file_offset,
 307                                       u64 len, bool uptodate)
 308 {
 309         struct btrfs_inode *inode = BTRFS_I(ordered->inode);
 310         struct btrfs_fs_info *fs_info = inode->root->fs_info;
 311
 312         lockdep_assert_held(&inode->ordered_tree_lock);
 313
 314         if (page) {
 315                 ASSERT(page->mapping);
 316                 ASSERT(page_offset(page) <= file_offset);
 317                 ASSERT(file_offset + len <= page_offset(page) + PAGE_SIZE);
 318
 319                 /*
 320                  * Ordered (Private2) bit indicates whether we still have
 321                  * pending io unfinished for the ordered extent.
 322                  *
 323                  * If there's no such bit, we need to skip to next range.
 324                  */
 325                 if (!btrfs_page_test_ordered(fs_info, page, file_offset, len))
 326                         return false;
 327                 btrfs_page_clear_ordered(fs_info, page, file_offset, len);
 328         }
 329
 330         /* Now we're fine to update the accounting. */
 331         if (WARN_ON_ONCE(len > ordered->bytes_left)) {
 332                 btrfs_crit(fs_info,
 333 "bad ordered extent accounting, root=%llu ino=%llu OE offset=%llu OE len=%llu to_dec=%llu left=%llu",
 334                            inode->root->root_key.objectid, btrfs_ino(inode),
 335                            ordered->file_offset, ordered->num_bytes,
 336                            len, ordered->bytes_left);
 337                 ordered->bytes_left = 0;
 338         } else {
 339                 ordered->bytes_left -= len;
 340         }
 341
 342         if (!uptodate)
 343                 set_bit(BTRFS_ORDERED_IOERR, &ordered->flags);
 344
 345         if (ordered->bytes_left)
 346                 return false;
 347
 348         /*
 349          * All the IO of the ordered extent is finished, we need to queue
 350          * the finish_func to be executed.
 351          */
 352         set_bit(BTRFS_ORDERED_IO_DONE, &ordered->flags);
 353         cond_wake_up(&ordered->wait);
 354         refcount_inc(&ordered->refs);
 355         trace_btrfs_ordered_extent_mark_finished(inode, ordered);
 356         return true;
 357 }
 358
 359 static void btrfs_queue_ordered_fn(struct btrfs_ordered_extent *ordered)
 360 {
 361         struct btrfs_inode *inode = BTRFS_I(ordered->inode);
 362         struct btrfs_fs_info *fs_info = inode->root->fs_info;
 363         struct btrfs_workqueue *wq = btrfs_is_free_space_inode(inode) ?
 364                 fs_info->endio_freespace_worker : fs_info->endio_write_workers;
 365
 366         btrfs_init_work(&ordered->work, finish_ordered_fn, NULL);
 367         btrfs_queue_work(wq, &ordered->work);
 368 }
 369
 370 bool btrfs_finish_ordered_extent(struct btrfs_ordered_extent *ordered,
 371                                  struct page *page, u64 file_offset, u64 len,
 372                                  bool uptodate)
 373 {
 374         struct btrfs_inode *inode = BTRFS_I(ordered->inode);
 375         unsigned long flags;
 376         bool ret;
 377
 378         trace_btrfs_finish_ordered_extent(inode, file_offset, len, uptodate);
 379
 380         spin_lock_irqsave(&inode->ordered_tree_lock, flags);
 381         ret = can_finish_ordered_extent(ordered, page, file_offset, len, uptodate);
 382         spin_unlock_irqrestore(&inode->ordered_tree_lock, flags);
 383
 384         if (ret)
 385                 btrfs_queue_ordered_fn(ordered);
 386         return ret;
 387 }
 388
 389 /*
 390  * Mark all ordered extents io inside the specified range finished.
 391  *
 392  * @page:        The involved page for the operation.
 393  *               For uncompressed buffered IO, the page status also needs to be
 394  *               updated to indicate whether the pending ordered io is finished.
 395  *               Can be NULL for direct IO and compressed write.
 396  *               For these cases, callers are ensured they won't execute the
 397  *               endio function twice.
 398  *
 399  * This function is called for endio, thus the range must have ordered
 400  * extent(s) covering it.
 401  */
 402 void btrfs_mark_ordered_io_finished(struct btrfs_inode *inode,
 403                                     struct page *page, u64 file_offset,
 404                                     u64 num_bytes, bool uptodate)
 405 {
 406         struct rb_node *node;
 407         struct btrfs_ordered_extent *entry = NULL;
 408         unsigned long flags;
 409         u64 cur = file_offset;
 410
 411         trace_btrfs_writepage_end_io_hook(inode, file_offset,
 412                                           file_offset + num_bytes - 1,
 413                                           uptodate);
 414
 415         spin_lock_irqsave(&inode->ordered_tree_lock, flags);
 416         while (cur < file_offset + num_bytes) {
 417                 u64 entry_end;
 418                 u64 end;
 419                 u32 len;
 420
 421                 node = ordered_tree_search(inode, cur);
 422                 /* No ordered extents at all */
 423                 if (!node)
 424                         break;
 425
 426                 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 427                 entry_end = entry->file_offset + entry->num_bytes;
 428                 /*
 429                  * |<-- OE --->|  |
 430                  *                cur
 431                  * Go to next OE.
 432                  */
 433                 if (cur >= entry_end) {
 434                         node = rb_next(node);
 435                         /* No more ordered extents, exit */
 436                         if (!node)
 437                                 break;
 438                         entry = rb_entry(node, struct btrfs_ordered_extent,
 439                                          rb_node);
 440
 441                         /* Go to next ordered extent and continue */
 442                         cur = entry->file_offset;
 443                         continue;
 444                 }
 445                 /*
 446                  * |    |<--- OE --->|
 447                  * cur
 448                  * Go to the start of OE.
 449                  */
 450                 if (cur < entry->file_offset) {
 451                         cur = entry->file_offset;
 452                         continue;
 453                 }
 454
 455                 /*
 456                  * Now we are definitely inside one ordered extent.
 457                  *
 458                  * |<--- OE --->|
 459                  *      |
 460                  *      cur
 461                  */
 462                 end = min(entry->file_offset + entry->num_bytes,
 463                           file_offset + num_bytes) - 1;
 464                 ASSERT(end + 1 - cur < U32_MAX);
 465                 len = end + 1 - cur;
 466
 467                 if (can_finish_ordered_extent(entry, page, cur, len, uptodate)) {
 468                         spin_unlock_irqrestore(&inode->ordered_tree_lock, flags);
 469                         btrfs_queue_ordered_fn(entry);
 470                         spin_lock_irqsave(&inode->ordered_tree_lock, flags);
 471                 }
 472                 cur += len;
 473         }
 474         spin_unlock_irqrestore(&inode->ordered_tree_lock, flags);
 475 }
 476
 477 /*
 478  * Finish IO for one ordered extent across a given range.  The range can only
 479  * contain one ordered extent.
 480  *
 481  * @cached:      The cached ordered extent. If not NULL, we can skip the tree
 482  *               search and use the ordered extent directly.
 483  *               Will be also used to store the finished ordered extent.
 484  * @file_offset: File offset for the finished IO
 485  * @io_size:     Length of the finish IO range
 486  *
 487  * Return true if the ordered extent is finished in the range, and update
 488  * @cached.
 489  * Return false otherwise.
 490  *
 491  * NOTE: The range can NOT cross multiple ordered extents.
 492  * Thus caller should ensure the range doesn't cross ordered extents.
 493  */
 494 bool btrfs_dec_test_ordered_pending(struct btrfs_inode *inode,
 495                                     struct btrfs_ordered_extent **cached,
 496                                     u64 file_offset, u64 io_size)
 497 {
 498         struct rb_node *node;
 499         struct btrfs_ordered_extent *entry = NULL;
 500         unsigned long flags;
 501         bool finished = false;
 502
 503         spin_lock_irqsave(&inode->ordered_tree_lock, flags);
 504         if (cached && *cached) {
 505                 entry = *cached;
 506                 goto have_entry;
 507         }
 508
 509         node = ordered_tree_search(inode, file_offset);
 510         if (!node)
 511                 goto out;
 512
 513         entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 514 have_entry:
 515         if (!in_range(file_offset, entry->file_offset, entry->num_bytes))
 516                 goto out;
 517
 518         if (io_size > entry->bytes_left)
 519                 btrfs_crit(inode->root->fs_info,
 520                            "bad ordered accounting left %llu size %llu",
 521                        entry->bytes_left, io_size);
 522
 523         entry->bytes_left -= io_size;
 524
 525         if (entry->bytes_left == 0) {
 526                 /*
 527                  * Ensure only one caller can set the flag and finished_ret
 528                  * accordingly
 529                  */
 530                 finished = !test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);
 531                 /* test_and_set_bit implies a barrier */
 532                 cond_wake_up_nomb(&entry->wait);
 533         }
 534 out:
 535         if (finished && cached && entry) {
 536                 *cached = entry;
 537                 refcount_inc(&entry->refs);
 538                 trace_btrfs_ordered_extent_dec_test_pending(inode, entry);
 539         }
 540         spin_unlock_irqrestore(&inode->ordered_tree_lock, flags);
 541         return finished;
 542 }
 543
 544 /*
 545  * used to drop a reference on an ordered extent.  This will free
 546  * the extent if the last reference is dropped
 547  */
 548 void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry)
 549 {
 550         struct list_head *cur;
 551         struct btrfs_ordered_sum *sum;
 552
 553         trace_btrfs_ordered_extent_put(BTRFS_I(entry->inode), entry);
 554
 555         if (refcount_dec_and_test(&entry->refs)) {
 556                 ASSERT(list_empty(&entry->root_extent_list));
 557                 ASSERT(list_empty(&entry->log_list));
 558                 ASSERT(RB_EMPTY_NODE(&entry->rb_node));
 559                 if (entry->inode)
 560                         btrfs_add_delayed_iput(BTRFS_I(entry->inode));
 561                 while (!list_empty(&entry->list)) {
 562                         cur = entry->list.next;
 563                         sum = list_entry(cur, struct btrfs_ordered_sum, list);
 564                         list_del(&sum->list);
 565                         kvfree(sum);
 566                 }
 567                 kmem_cache_free(btrfs_ordered_extent_cache, entry);
 568         }
 569 }
 570
 571 /*
 572  * remove an ordered extent from the tree.  No references are dropped
 573  * and waiters are woken up.
 574  */
 575 void btrfs_remove_ordered_extent(struct btrfs_inode *btrfs_inode,
 576                                  struct btrfs_ordered_extent *entry)
 577 {
 578         struct btrfs_root *root = btrfs_inode->root;
 579         struct btrfs_fs_info *fs_info = root->fs_info;
 580         struct rb_node *node;
 581         bool pending;
 582         bool freespace_inode;
 583
 584         /*
 585          * If this is a free space inode the thread has not acquired the ordered
 586          * extents lockdep map.
 587          */
 588         freespace_inode = btrfs_is_free_space_inode(btrfs_inode);
 589
 590         btrfs_lockdep_acquire(fs_info, btrfs_trans_pending_ordered);
 591         /* This is paired with btrfs_alloc_ordered_extent. */
 592         spin_lock(&btrfs_inode->lock);
 593         btrfs_mod_outstanding_extents(btrfs_inode, -1);
 594         spin_unlock(&btrfs_inode->lock);
 595         if (root != fs_info->tree_root) {
 596                 u64 release;
 597
 598                 if (test_bit(BTRFS_ORDERED_ENCODED, &entry->flags))
 599                         release = entry->disk_num_bytes;
 600                 else
 601                         release = entry->num_bytes;
 602                 btrfs_delalloc_release_metadata(btrfs_inode, release, false);
 603         }
 604
 605         percpu_counter_add_batch(&fs_info->ordered_bytes, -entry->num_bytes,
 606                                  fs_info->delalloc_batch);
 607
 608         spin_lock_irq(&btrfs_inode->ordered_tree_lock);
 609         node = &entry->rb_node;
 610         rb_erase(node, &btrfs_inode->ordered_tree);
 611         RB_CLEAR_NODE(node);
 612         if (btrfs_inode->ordered_tree_last == node)
 613                 btrfs_inode->ordered_tree_last = NULL;
 614         set_bit(BTRFS_ORDERED_COMPLETE, &entry->flags);
 615         pending = test_and_clear_bit(BTRFS_ORDERED_PENDING, &entry->flags);
 616         spin_unlock_irq(&btrfs_inode->ordered_tree_lock);
 617
 618         /*
 619          * The current running transaction is waiting on us, we need to let it
 620          * know that we're complete and wake it up.
 621          */
 622         if (pending) {
 623                 struct btrfs_transaction *trans;
 624
 625                 /*
 626                  * The checks for trans are just a formality, it should be set,
 627                  * but if it isn't we don't want to deref/assert under the spin
 628                  * lock, so be nice and check if trans is set, but ASSERT() so
 629                  * if it isn't set a developer will notice.
 630                  */
 631                 spin_lock(&fs_info->trans_lock);
 632                 trans = fs_info->running_transaction;
 633                 if (trans)
 634                         refcount_inc(&trans->use_count);
 635                 spin_unlock(&fs_info->trans_lock);
 636
 637                 ASSERT(trans || BTRFS_FS_ERROR(fs_info));
 638                 if (trans) {
 639                         if (atomic_dec_and_test(&trans->pending_ordered))
 640                                 wake_up(&trans->pending_wait);
 641                         btrfs_put_transaction(trans);
 642                 }
 643         }
 644
 645         btrfs_lockdep_release(fs_info, btrfs_trans_pending_ordered);
 646
 647         spin_lock(&root->ordered_extent_lock);
 648         list_del_init(&entry->root_extent_list);
 649         root->nr_ordered_extents--;
 650
 651         trace_btrfs_ordered_extent_remove(btrfs_inode, entry);
 652
 653         if (!root->nr_ordered_extents) {
 654                 spin_lock(&fs_info->ordered_root_lock);
 655                 BUG_ON(list_empty(&root->ordered_root));
 656                 list_del_init(&root->ordered_root);
 657                 spin_unlock(&fs_info->ordered_root_lock);
 658         }
 659         spin_unlock(&root->ordered_extent_lock);
 660         wake_up(&entry->wait);
 661         if (!freespace_inode)
 662                 btrfs_lockdep_release(fs_info, btrfs_ordered_extent);
 663 }
 664
 665 static void btrfs_run_ordered_extent_work(struct btrfs_work *work)
 666 {
 667         struct btrfs_ordered_extent *ordered;
 668
 669         ordered = container_of(work, struct btrfs_ordered_extent, flush_work);
 670         btrfs_start_ordered_extent(ordered);
 671         complete(&ordered->completion);
 672 }
 673
 674 /*
 675  * wait for all the ordered extents in a root.  This is done when balancing
 676  * space between drives.
 677  */
 678 u64 btrfs_wait_ordered_extents(struct btrfs_root *root, u64 nr,
 679                                const u64 range_start, const u64 range_len)
 680 {
 681         struct btrfs_fs_info *fs_info = root->fs_info;
 682         LIST_HEAD(splice);
 683         LIST_HEAD(skipped);
 684         LIST_HEAD(works);
 685         struct btrfs_ordered_extent *ordered, *next;
 686         u64 count = 0;
 687         const u64 range_end = range_start + range_len;
 688
 689         mutex_lock(&root->ordered_extent_mutex);
 690         spin_lock(&root->ordered_extent_lock);
 691         list_splice_init(&root->ordered_extents, &splice);
 692         while (!list_empty(&splice) && nr) {
 693                 ordered = list_first_entry(&splice, struct btrfs_ordered_extent,
 694                                            root_extent_list);
 695
 696                 if (range_end <= ordered->disk_bytenr ||
 697                     ordered->disk_bytenr + ordered->disk_num_bytes <= range_start) {
 698                         list_move_tail(&ordered->root_extent_list, &skipped);
 699                         cond_resched_lock(&root->ordered_extent_lock);
 700                         continue;
 701                 }
 702
 703                 list_move_tail(&ordered->root_extent_list,
 704                                &root->ordered_extents);
 705                 refcount_inc(&ordered->refs);
 706                 spin_unlock(&root->ordered_extent_lock);
 707
 708                 btrfs_init_work(&ordered->flush_work,
 709                                 btrfs_run_ordered_extent_work, NULL);
 710                 list_add_tail(&ordered->work_list, &works);
 711                 btrfs_queue_work(fs_info->flush_workers, &ordered->flush_work);
 712
 713                 cond_resched();
 714                 spin_lock(&root->ordered_extent_lock);
 715                 if (nr != U64_MAX)
 716                         nr--;
 717                 count++;
 718         }
 719         list_splice_tail(&skipped, &root->ordered_extents);
 720         list_splice_tail(&splice, &root->ordered_extents);
 721         spin_unlock(&root->ordered_extent_lock);
 722
 723         list_for_each_entry_safe(ordered, next, &works, work_list) {
 724                 list_del_init(&ordered->work_list);
 725                 wait_for_completion(&ordered->completion);
 726                 btrfs_put_ordered_extent(ordered);
 727                 cond_resched();
 728         }
 729         mutex_unlock(&root->ordered_extent_mutex);
 730
 731         return count;
 732 }
 733
 734 void btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, u64 nr,
 735                              const u64 range_start, const u64 range_len)
 736 {
 737         struct btrfs_root *root;
 738         LIST_HEAD(splice);
 739         u64 done;
 740
 741         mutex_lock(&fs_info->ordered_operations_mutex);
 742         spin_lock(&fs_info->ordered_root_lock);
 743         list_splice_init(&fs_info->ordered_roots, &splice);
 744         while (!list_empty(&splice) && nr) {
 745                 root = list_first_entry(&splice, struct btrfs_root,
 746                                         ordered_root);
 747                 root = btrfs_grab_root(root);
 748                 BUG_ON(!root);
 749                 list_move_tail(&root->ordered_root,
 750                                &fs_info->ordered_roots);
 751                 spin_unlock(&fs_info->ordered_root_lock);
 752
 753                 done = btrfs_wait_ordered_extents(root, nr,
 754                                                   range_start, range_len);
 755                 btrfs_put_root(root);
 756
 757                 spin_lock(&fs_info->ordered_root_lock);
 758                 if (nr != U64_MAX) {
 759                         nr -= done;
 760                 }
 761         }
 762         list_splice_tail(&splice, &fs_info->ordered_roots);
 763         spin_unlock(&fs_info->ordered_root_lock);
 764         mutex_unlock(&fs_info->ordered_operations_mutex);
 765 }
 766
 767 /*
 768  * Start IO and wait for a given ordered extent to finish.
 769  *
 770  * Wait on page writeback for all the pages in the extent and the IO completion
 771  * code to insert metadata into the btree corresponding to the extent.
 772  */
 773 void btrfs_start_ordered_extent(struct btrfs_ordered_extent *entry)
 774 {
 775         u64 start = entry->file_offset;
 776         u64 end = start + entry->num_bytes - 1;
 777         struct btrfs_inode *inode = BTRFS_I(entry->inode);
 778         bool freespace_inode;
 779
 780         trace_btrfs_ordered_extent_start(inode, entry);
 781
 782         /*
 783          * If this is a free space inode do not take the ordered extents lockdep
 784          * map.
 785          */
 786         freespace_inode = btrfs_is_free_space_inode(inode);
 787
 788         /*
 789          * pages in the range can be dirty, clean or writeback.  We
 790          * start IO on any dirty ones so the wait doesn't stall waiting
 791          * for the flusher thread to find them
 792          */
 793         if (!test_bit(BTRFS_ORDERED_DIRECT, &entry->flags))
 794                 filemap_fdatawrite_range(inode->vfs_inode.i_mapping, start, end);
 795
 796         if (!freespace_inode)
 797                 btrfs_might_wait_for_event(inode->root->fs_info, btrfs_ordered_extent);
 798         wait_event(entry->wait, test_bit(BTRFS_ORDERED_COMPLETE, &entry->flags));
 799 }
 800
 801 /*
 802  * Used to wait on ordered extents across a large range of bytes.
 803  */
 804 int btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len)
 805 {
 806         int ret = 0;
 807         int ret_wb = 0;
 808         u64 end;
 809         u64 orig_end;
 810         struct btrfs_ordered_extent *ordered;
 811
 812         if (start + len < start) {
 813                 orig_end = OFFSET_MAX;
 814         } else {
 815                 orig_end = start + len - 1;
 816                 if (orig_end > OFFSET_MAX)
 817                         orig_end = OFFSET_MAX;
 818         }
 819
 820         /* start IO across the range first to instantiate any delalloc
 821          * extents
 822          */
 823         ret = btrfs_fdatawrite_range(inode, start, orig_end);
 824         if (ret)
 825                 return ret;
 826
 827         /*
 828          * If we have a writeback error don't return immediately. Wait first
 829          * for any ordered extents that haven't completed yet. This is to make
 830          * sure no one can dirty the same page ranges and call writepages()
 831          * before the ordered extents complete - to avoid failures (-EEXIST)
 832          * when adding the new ordered extents to the ordered tree.
 833          */
 834         ret_wb = filemap_fdatawait_range(inode->i_mapping, start, orig_end);
 835
 836         end = orig_end;
 837         while (1) {
 838                 ordered = btrfs_lookup_first_ordered_extent(BTRFS_I(inode), end);
 839                 if (!ordered)
 840                         break;
 841                 if (ordered->file_offset > orig_end) {
 842                         btrfs_put_ordered_extent(ordered);
 843                         break;
 844                 }
 845                 if (ordered->file_offset + ordered->num_bytes <= start) {
 846                         btrfs_put_ordered_extent(ordered);
 847                         break;
 848                 }
 849                 btrfs_start_ordered_extent(ordered);
 850                 end = ordered->file_offset;
 851                 /*
 852                  * If the ordered extent had an error save the error but don't
 853                  * exit without waiting first for all other ordered extents in
 854                  * the range to complete.
 855                  */
 856                 if (test_bit(BTRFS_ORDERED_IOERR, &ordered->flags))
 857                         ret = -EIO;
 858                 btrfs_put_ordered_extent(ordered);
 859                 if (end == 0 || end == start)
 860                         break;
 861                 end--;
 862         }
 863         return ret_wb ? ret_wb : ret;
 864 }
 865
 866 /*
 867  * find an ordered extent corresponding to file_offset.  return NULL if
 868  * nothing is found, otherwise take a reference on the extent and return it
 869  */
 870 struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct btrfs_inode *inode,
 871                                                          u64 file_offset)
 872 {
 873         struct rb_node *node;
 874         struct btrfs_ordered_extent *entry = NULL;
 875         unsigned long flags;
 876
 877         spin_lock_irqsave(&inode->ordered_tree_lock, flags);
 878         node = ordered_tree_search(inode, file_offset);
 879         if (!node)
 880                 goto out;
 881
 882         entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 883         if (!in_range(file_offset, entry->file_offset, entry->num_bytes))
 884                 entry = NULL;
 885         if (entry) {
 886                 refcount_inc(&entry->refs);
 887                 trace_btrfs_ordered_extent_lookup(inode, entry);
 888         }
 889 out:
 890         spin_unlock_irqrestore(&inode->ordered_tree_lock, flags);
 891         return entry;
 892 }
 893
 894 /* Since the DIO code tries to lock a wide area we need to look for any ordered
 895  * extents that exist in the range, rather than just the start of the range.
 896  */
 897 struct btrfs_ordered_extent *btrfs_lookup_ordered_range(
 898                 struct btrfs_inode *inode, u64 file_offset, u64 len)
 899 {
 900         struct rb_node *node;
 901         struct btrfs_ordered_extent *entry = NULL;
 902
 903         spin_lock_irq(&inode->ordered_tree_lock);
 904         node = ordered_tree_search(inode, file_offset);
 905         if (!node) {
 906                 node = ordered_tree_search(inode, file_offset + len);
 907                 if (!node)
 908                         goto out;
 909         }
 910
 911         while (1) {
 912                 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 913                 if (range_overlaps(entry, file_offset, len))
 914                         break;
 915
 916                 if (entry->file_offset >= file_offset + len) {
 917                         entry = NULL;
 918                         break;
 919                 }
 920                 entry = NULL;
 921                 node = rb_next(node);
 922                 if (!node)
 923                         break;
 924         }
 925 out:
 926         if (entry) {
 927                 refcount_inc(&entry->refs);
 928                 trace_btrfs_ordered_extent_lookup_range(inode, entry);
 929         }
 930         spin_unlock_irq(&inode->ordered_tree_lock);
 931         return entry;
 932 }
 933
 934 /*
 935  * Adds all ordered extents to the given list. The list ends up sorted by the
 936  * file_offset of the ordered extents.
 937  */
 938 void btrfs_get_ordered_extents_for_logging(struct btrfs_inode *inode,
 939                                            struct list_head *list)
 940 {
 941         struct rb_node *n;
 942
 943         ASSERT(inode_is_locked(&inode->vfs_inode));
 944
 945         spin_lock_irq(&inode->ordered_tree_lock);
 946         for (n = rb_first(&inode->ordered_tree); n; n = rb_next(n)) {
 947                 struct btrfs_ordered_extent *ordered;
 948
 949                 ordered = rb_entry(n, struct btrfs_ordered_extent, rb_node);
 950
 951                 if (test_bit(BTRFS_ORDERED_LOGGED, &ordered->flags))
 952                         continue;
 953
 954                 ASSERT(list_empty(&ordered->log_list));
 955                 list_add_tail(&ordered->log_list, list);
 956                 refcount_inc(&ordered->refs);
 957                 trace_btrfs_ordered_extent_lookup_for_logging(inode, ordered);
 958         }
 959         spin_unlock_irq(&inode->ordered_tree_lock);
 960 }
 961
 962 /*
 963  * lookup and return any extent before 'file_offset'.  NULL is returned
 964  * if none is found
 965  */
 966 struct btrfs_ordered_extent *
 967 btrfs_lookup_first_ordered_extent(struct btrfs_inode *inode, u64 file_offset)
 968 {
 969         struct rb_node *node;
 970         struct btrfs_ordered_extent *entry = NULL;
 971
 972         spin_lock_irq(&inode->ordered_tree_lock);
 973         node = ordered_tree_search(inode, file_offset);
 974         if (!node)
 975                 goto out;
 976
 977         entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 978         refcount_inc(&entry->refs);
 979         trace_btrfs_ordered_extent_lookup_first(inode, entry);
 980 out:
 981         spin_unlock_irq(&inode->ordered_tree_lock);
 982         return entry;
 983 }
 984
 985 /*
 986  * Lookup the first ordered extent that overlaps the range
 987  * [@file_offset, @file_offset + @len).
 988  *
 989  * The difference between this and btrfs_lookup_first_ordered_extent() is
 990  * that this one won't return any ordered extent that does not overlap the range.
 991  * And the difference against btrfs_lookup_ordered_extent() is, this function
 992  * ensures the first ordered extent gets returned.
 993  */
 994 struct btrfs_ordered_extent *btrfs_lookup_first_ordered_range(
 995                         struct btrfs_inode *inode, u64 file_offset, u64 len)
 996 {
 997         struct rb_node *node;
 998         struct rb_node *cur;
 999         struct rb_node *prev;
1000         struct rb_node *next;
1001         struct btrfs_ordered_extent *entry = NULL;
1002
1003         spin_lock_irq(&inode->ordered_tree_lock);
1004         node = inode->ordered_tree.rb_node;
1005         /*
1006          * Here we don't want to use tree_search() which will use tree->last
1007          * and screw up the search order.
1008          * And __tree_search() can't return the adjacent ordered extents
1009          * either, thus here we do our own search.
1010          */
1011         while (node) {
1012                 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
1013
1014                 if (file_offset < entry->file_offset) {
1015                         node = node->rb_left;
1016                 } else if (file_offset >= entry_end(entry)) {
1017                         node = node->rb_right;
1018                 } else {
1019                         /*
1020                          * Direct hit, got an ordered extent that starts at
1021                          * @file_offset
1022                          */
1023                         goto out;
1024                 }
1025         }
1026         if (!entry) {
1027                 /* Empty tree */
1028                 goto out;
1029         }
1030
1031         cur = &entry->rb_node;
1032         /* We got an entry around @file_offset, check adjacent entries */
1033         if (entry->file_offset < file_offset) {
1034                 prev = cur;
1035                 next = rb_next(cur);
1036         } else {
1037                 prev = rb_prev(cur);
1038                 next = cur;
1039         }
1040         if (prev) {
1041                 entry = rb_entry(prev, struct btrfs_ordered_extent, rb_node);
1042                 if (range_overlaps(entry, file_offset, len))
1043                         goto out;
1044         }
1045         if (next) {
1046                 entry = rb_entry(next, struct btrfs_ordered_extent, rb_node);
1047                 if (range_overlaps(entry, file_offset, len))
1048                         goto out;
1049         }
1050         /* No ordered extent in the range */
1051         entry = NULL;
1052 out:
1053         if (entry) {
1054                 refcount_inc(&entry->refs);
1055                 trace_btrfs_ordered_extent_lookup_first_range(inode, entry);
1056         }
1057
1058         spin_unlock_irq(&inode->ordered_tree_lock);
1059         return entry;
1060 }
1061
1062 /*
1063  * Lock the passed range and ensures all pending ordered extents in it are run
1064  * to completion.
1065  *
1066  * @inode:        Inode whose ordered tree is to be searched
1067  * @start:        Beginning of range to flush
1068  * @end:          Last byte of range to lock
1069  * @cached_state: If passed, will return the extent state responsible for the
1070  *                locked range. It's the caller's responsibility to free the
1071  *                cached state.
1072  *
1073  * Always return with the given range locked, ensuring after it's called no
1074  * order extent can be pending.
1075  */
1076 void btrfs_lock_and_flush_ordered_range(struct btrfs_inode *inode, u64 start,
1077                                         u64 end,
1078                                         struct extent_state **cached_state)
1079 {
1080         struct btrfs_ordered_extent *ordered;
1081         struct extent_state *cache = NULL;
1082         struct extent_state **cachedp = &cache;
1083
1084         if (cached_state)
1085                 cachedp = cached_state;
1086
1087         while (1) {
1088                 lock_extent(&inode->io_tree, start, end, cachedp);
1089                 ordered = btrfs_lookup_ordered_range(inode, start,
1090                                                      end - start + 1);
1091                 if (!ordered) {
1092                         /*
1093                          * If no external cached_state has been passed then
1094                          * decrement the extra ref taken for cachedp since we
1095                          * aren't exposing it outside of this function
1096                          */
1097                         if (!cached_state)
1098                                 refcount_dec(&cache->refs);
1099                         break;
1100                 }
1101                 unlock_extent(&inode->io_tree, start, end, cachedp);
1102                 btrfs_start_ordered_extent(ordered);
1103                 btrfs_put_ordered_extent(ordered);
1104         }
1105 }
1106
1107 /*
1108  * Lock the passed range and ensure all pending ordered extents in it are run
1109  * to completion in nowait mode.
1110  *
1111  * Return true if btrfs_lock_ordered_range does not return any extents,
1112  * otherwise false.
1113  */
1114 bool btrfs_try_lock_ordered_range(struct btrfs_inode *inode, u64 start, u64 end,
1115                                   struct extent_state **cached_state)
1116 {
1117         struct btrfs_ordered_extent *ordered;
1118
1119         if (!try_lock_extent(&inode->io_tree, start, end, cached_state))
1120                 return false;
1121
1122         ordered = btrfs_lookup_ordered_range(inode, start, end - start + 1);
1123         if (!ordered)
1124                 return true;
1125
1126         btrfs_put_ordered_extent(ordered);
1127         unlock_extent(&inode->io_tree, start, end, cached_state);
1128
1129         return false;
1130 }
1131
1132 /* Split out a new ordered extent for this first @len bytes of @ordered. */
1133 struct btrfs_ordered_extent *btrfs_split_ordered_extent(
1134                         struct btrfs_ordered_extent *ordered, u64 len)
1135 {
1136         struct btrfs_inode *inode = BTRFS_I(ordered->inode);
1137         struct btrfs_root *root = inode->root;
1138         struct btrfs_fs_info *fs_info = root->fs_info;
1139         u64 file_offset = ordered->file_offset;
1140         u64 disk_bytenr = ordered->disk_bytenr;
1141         unsigned long flags = ordered->flags;
1142         struct btrfs_ordered_sum *sum, *tmpsum;
1143         struct btrfs_ordered_extent *new;
1144         struct rb_node *node;
1145         u64 offset = 0;
1146
1147         trace_btrfs_ordered_extent_split(inode, ordered);
1148
1149         ASSERT(!(flags & (1U << BTRFS_ORDERED_COMPRESSED)));
1150
1151         /*
1152          * The entire bio must be covered by the ordered extent, but we can't
1153          * reduce the original extent to a zero length either.
1154          */
1155         if (WARN_ON_ONCE(len >= ordered->num_bytes))
1156                 return ERR_PTR(-EINVAL);
1157         /* We cannot split partially completed ordered extents. */
1158         if (ordered->bytes_left) {
1159                 ASSERT(!(flags & ~BTRFS_ORDERED_TYPE_FLAGS));
1160                 if (WARN_ON_ONCE(ordered->bytes_left != ordered->disk_num_bytes))
1161                         return ERR_PTR(-EINVAL);
1162         }
1163         /* We cannot split a compressed ordered extent. */
1164         if (WARN_ON_ONCE(ordered->disk_num_bytes != ordered->num_bytes))
1165                 return ERR_PTR(-EINVAL);
1166
1167         new = alloc_ordered_extent(inode, file_offset, len, len, disk_bytenr,
1168                                    len, 0, flags, ordered->compress_type);
1169         if (IS_ERR(new))
1170                 return new;
1171
1172         /* One ref for the tree. */
1173         refcount_inc(&new->refs);
1174
1175         spin_lock_irq(&root->ordered_extent_lock);
1176         spin_lock(&inode->ordered_tree_lock);
1177         /* Remove from tree once */
1178         node = &ordered->rb_node;
1179         rb_erase(node, &inode->ordered_tree);
1180         RB_CLEAR_NODE(node);
1181         if (inode->ordered_tree_last == node)
1182                 inode->ordered_tree_last = NULL;
1183
1184         ordered->file_offset += len;
1185         ordered->disk_bytenr += len;
1186         ordered->num_bytes -= len;
1187         ordered->disk_num_bytes -= len;
1188
1189         if (test_bit(BTRFS_ORDERED_IO_DONE, &ordered->flags)) {
1190                 ASSERT(ordered->bytes_left == 0);
1191                 new->bytes_left = 0;
1192         } else {
1193                 ordered->bytes_left -= len;
1194         }
1195
1196         if (test_bit(BTRFS_ORDERED_TRUNCATED, &ordered->flags)) {
1197                 if (ordered->truncated_len > len) {
1198                         ordered->truncated_len -= len;
1199                 } else {
1200                         new->truncated_len = ordered->truncated_len;
1201                         ordered->truncated_len = 0;
1202                 }
1203         }
1204
1205         list_for_each_entry_safe(sum, tmpsum, &ordered->list, list) {
1206                 if (offset == len)
1207                         break;
1208                 list_move_tail(&sum->list, &new->list);
1209                 offset += sum->len;
1210         }
1211
1212         /* Re-insert the node */
1213         node = tree_insert(&inode->ordered_tree, ordered->file_offset,
1214                            &ordered->rb_node);
1215         if (node)
1216                 btrfs_panic(fs_info, -EEXIST,
1217                         "zoned: inconsistency in ordered tree at offset %llu",
1218                         ordered->file_offset);
1219
1220         node = tree_insert(&inode->ordered_tree, new->file_offset, &new->rb_node);
1221         if (node)
1222                 btrfs_panic(fs_info, -EEXIST,
1223                         "zoned: inconsistency in ordered tree at offset %llu",
1224                         new->file_offset);
1225         spin_unlock(&inode->ordered_tree_lock);
1226
1227         list_add_tail(&new->root_extent_list, &root->ordered_extents);
1228         root->nr_ordered_extents++;
1229         spin_unlock_irq(&root->ordered_extent_lock);
1230         return new;
1231 }
1232
1233 int __init ordered_data_init(void)
1234 {
1235         btrfs_ordered_extent_cache = kmem_cache_create("btrfs_ordered_extent",
1236                                      sizeof(struct btrfs_ordered_extent), 0,
1237                                      SLAB_MEM_SPREAD,
1238                                      NULL);
1239         if (!btrfs_ordered_extent_cache)
1240                 return -ENOMEM;
1241
1242         return 0;
1243 }
1244
1245 void __cold ordered_data_exit(void)
1246 {
1247         kmem_cache_destroy(btrfs_ordered_extent_cache);
1248 }