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
  23 static struct kmem_cache *btrfs_ordered_extent_cache;
  24
  25 static u64 entry_end(struct btrfs_ordered_extent *entry)
  26 {
  27         if (entry->file_offset + entry->num_bytes < entry->file_offset)
  28                 return (u64)-1;
  29         return entry->file_offset + entry->num_bytes;
  30 }
  31
  32 /* returns NULL if the insertion worked, or it returns the node it did find
  33  * in the tree
  34  */
  35 static struct rb_node *tree_insert(struct rb_root *root, u64 file_offset,
  36                                    struct rb_node *node)
  37 {
  38         struct rb_node **p = &root->rb_node;
  39         struct rb_node *parent = NULL;
  40         struct btrfs_ordered_extent *entry;
  41
  42         while (*p) {
  43                 parent = *p;
  44                 entry = rb_entry(parent, struct btrfs_ordered_extent, rb_node);
  45
  46                 if (file_offset < entry->file_offset)
  47                         p = &(*p)->rb_left;
  48                 else if (file_offset >= entry_end(entry))
  49                         p = &(*p)->rb_right;
  50                 else
  51                         return parent;
  52         }
  53
  54         rb_link_node(node, parent, p);
  55         rb_insert_color(node, root);
  56         return NULL;
  57 }
  58
  59 /*
  60  * look for a given offset in the tree, and if it can't be found return the
  61  * first lesser offset
  62  */
  63 static struct rb_node *__tree_search(struct rb_root *root, u64 file_offset,
  64                                      struct rb_node **prev_ret)
  65 {
  66         struct rb_node *n = root->rb_node;
  67         struct rb_node *prev = NULL;
  68         struct rb_node *test;
  69         struct btrfs_ordered_extent *entry;
  70         struct btrfs_ordered_extent *prev_entry = NULL;
  71
  72         while (n) {
  73                 entry = rb_entry(n, struct btrfs_ordered_extent, rb_node);
  74                 prev = n;
  75                 prev_entry = entry;
  76
  77                 if (file_offset < entry->file_offset)
  78                         n = n->rb_left;
  79                 else if (file_offset >= entry_end(entry))
  80                         n = n->rb_right;
  81                 else
  82                         return n;
  83         }
  84         if (!prev_ret)
  85                 return NULL;
  86
  87         while (prev && file_offset >= entry_end(prev_entry)) {
  88                 test = rb_next(prev);
  89                 if (!test)
  90                         break;
  91                 prev_entry = rb_entry(test, struct btrfs_ordered_extent,
  92                                       rb_node);
  93                 if (file_offset < entry_end(prev_entry))
  94                         break;
  95
  96                 prev = test;
  97         }
  98         if (prev)
  99                 prev_entry = rb_entry(prev, struct btrfs_ordered_extent,
 100                                       rb_node);
 101         while (prev && file_offset < entry_end(prev_entry)) {
 102                 test = rb_prev(prev);
 103                 if (!test)
 104                         break;
 105                 prev_entry = rb_entry(test, struct btrfs_ordered_extent,
 106                                       rb_node);
 107                 prev = test;
 108         }
 109         *prev_ret = prev;
 110         return NULL;
 111 }
 112
 113 static int range_overlaps(struct btrfs_ordered_extent *entry, u64 file_offset,
 114                           u64 len)
 115 {
 116         if (file_offset + len <= entry->file_offset ||
 117             entry->file_offset + entry->num_bytes <= file_offset)
 118                 return 0;
 119         return 1;
 120 }
 121
 122 /*
 123  * look find the first ordered struct that has this offset, otherwise
 124  * the first one less than this offset
 125  */
 126 static inline struct rb_node *ordered_tree_search(struct btrfs_inode *inode,
 127                                                   u64 file_offset)
 128 {
 129         struct rb_node *prev = NULL;
 130         struct rb_node *ret;
 131         struct btrfs_ordered_extent *entry;
 132
 133         if (inode->ordered_tree_last) {
 134                 entry = rb_entry(inode->ordered_tree_last, struct btrfs_ordered_extent,
 135                                  rb_node);
 136                 if (in_range(file_offset, entry->file_offset, entry->num_bytes))
 137                         return inode->ordered_tree_last;
 138         }
 139         ret = __tree_search(&inode->ordered_tree, file_offset, &prev);
 140         if (!ret)
 141                 ret = prev;
 142         if (ret)
 143                 inode->ordered_tree_last = ret;
 144         return ret;
 145 }
 146
 147 static struct btrfs_ordered_extent *alloc_ordered_extent(
 148                         struct btrfs_inode *inode, u64 file_offset, u64 num_bytes,
 149                         u64 ram_bytes, u64 disk_bytenr, u64 disk_num_bytes,
 150                         u64 offset, unsigned long flags, int compress_type)
 151 {
 152         struct btrfs_ordered_extent *entry;
 153         int ret;
 154         u64 qgroup_rsv = 0;
 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, &qgroup_rsv);
 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, &qgroup_rsv);
 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 = qgroup_rsv;
 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 void btrfs_mark_ordered_extent_error(struct btrfs_ordered_extent *ordered)
 298 {
 299         if (!test_and_set_bit(BTRFS_ORDERED_IOERR, &ordered->flags))
 300                 mapping_set_error(ordered->inode->i_mapping, -EIO);
 301 }
 302
 303 static void finish_ordered_fn(struct btrfs_work *work)
 304 {
 305         struct btrfs_ordered_extent *ordered_extent;
 306
 307         ordered_extent = container_of(work, struct btrfs_ordered_extent, work);
 308         btrfs_finish_ordered_io(ordered_extent);
 309 }
 310
 311 static bool can_finish_ordered_extent(struct btrfs_ordered_extent *ordered,
 312                                       struct page *page, u64 file_offset,
 313                                       u64 len, bool uptodate)
 314 {
 315         struct btrfs_inode *inode = BTRFS_I(ordered->inode);
 316         struct btrfs_fs_info *fs_info = inode->root->fs_info;
 317
 318         lockdep_assert_held(&inode->ordered_tree_lock);
 319
 320         if (page) {
 321                 ASSERT(page->mapping);
 322                 ASSERT(page_offset(page) <= file_offset);
 323                 ASSERT(file_offset + len <= page_offset(page) + PAGE_SIZE);
 324
 325                 /*
 326                  * Ordered (Private2) bit indicates whether we still have
 327                  * pending io unfinished for the ordered extent.
 328                  *
 329                  * If there's no such bit, we need to skip to next range.
 330                  */
 331                 if (!btrfs_folio_test_ordered(fs_info, page_folio(page),
 332                                               file_offset, len))
 333                         return false;
 334                 btrfs_folio_clear_ordered(fs_info, page_folio(page), file_offset, len);
 335         }
 336
 337         /* Now we're fine to update the accounting. */
 338         if (WARN_ON_ONCE(len > ordered->bytes_left)) {
 339                 btrfs_crit(fs_info,
 340 "bad ordered extent accounting, root=%llu ino=%llu OE offset=%llu OE len=%llu to_dec=%llu left=%llu",
 341                            btrfs_root_id(inode->root), btrfs_ino(inode),
 342                            ordered->file_offset, ordered->num_bytes,
 343                            len, ordered->bytes_left);
 344                 ordered->bytes_left = 0;
 345         } else {
 346                 ordered->bytes_left -= len;
 347         }
 348
 349         if (!uptodate)
 350                 set_bit(BTRFS_ORDERED_IOERR, &ordered->flags);
 351
 352         if (ordered->bytes_left)
 353                 return false;
 354
 355         /*
 356          * All the IO of the ordered extent is finished, we need to queue
 357          * the finish_func to be executed.
 358          */
 359         set_bit(BTRFS_ORDERED_IO_DONE, &ordered->flags);
 360         cond_wake_up(&ordered->wait);
 361         refcount_inc(&ordered->refs);
 362         trace_btrfs_ordered_extent_mark_finished(inode, ordered);
 363         return true;
 364 }
 365
 366 static void btrfs_queue_ordered_fn(struct btrfs_ordered_extent *ordered)
 367 {
 368         struct btrfs_inode *inode = BTRFS_I(ordered->inode);
 369         struct btrfs_fs_info *fs_info = inode->root->fs_info;
 370         struct btrfs_workqueue *wq = btrfs_is_free_space_inode(inode) ?
 371                 fs_info->endio_freespace_worker : fs_info->endio_write_workers;
 372
 373         btrfs_init_work(&ordered->work, finish_ordered_fn, NULL);
 374         btrfs_queue_work(wq, &ordered->work);
 375 }
 376
 377 bool btrfs_finish_ordered_extent(struct btrfs_ordered_extent *ordered,
 378                                  struct page *page, u64 file_offset, u64 len,
 379                                  bool uptodate)
 380 {
 381         struct btrfs_inode *inode = BTRFS_I(ordered->inode);
 382         unsigned long flags;
 383         bool ret;
 384
 385         trace_btrfs_finish_ordered_extent(inode, file_offset, len, uptodate);
 386
 387         spin_lock_irqsave(&inode->ordered_tree_lock, flags);
 388         ret = can_finish_ordered_extent(ordered, page, file_offset, len, uptodate);
 389         spin_unlock_irqrestore(&inode->ordered_tree_lock, flags);
 390
 391         /*
 392          * If this is a COW write it means we created new extent maps for the
 393          * range and they point to unwritten locations if we got an error either
 394          * before submitting a bio or during IO.
 395          *
 396          * We have marked the ordered extent with BTRFS_ORDERED_IOERR, and we
 397          * are queuing its completion below. During completion, at
 398          * btrfs_finish_one_ordered(), we will drop the extent maps for the
 399          * unwritten extents.
 400          *
 401          * However because completion runs in a work queue we can end up having
 402          * a fast fsync running before that. In the case of direct IO, once we
 403          * unlock the inode the fsync might start, and we queue the completion
 404          * before unlocking the inode. In the case of buffered IO when writeback
 405          * finishes (end_bbio_data_write()) we queue the completion, so if the
 406          * writeback was triggered by a fast fsync, the fsync might start
 407          * logging before ordered extent completion runs in the work queue.
 408          *
 409          * The fast fsync will log file extent items based on the extent maps it
 410          * finds, so if by the time it collects extent maps the ordered extent
 411          * completion didn't happen yet, it will log file extent items that
 412          * point to unwritten extents, resulting in a corruption if a crash
 413          * happens and the log tree is replayed. Note that a fast fsync does not
 414          * wait for completion of ordered extents in order to reduce latency.
 415          *
 416          * Set a flag in the inode so that the next fast fsync will wait for
 417          * ordered extents to complete before starting to log.
 418          */
 419         if (!uptodate && !test_bit(BTRFS_ORDERED_NOCOW, &ordered->flags))
 420                 set_bit(BTRFS_INODE_COW_WRITE_ERROR, &inode->runtime_flags);
 421
 422         if (ret)
 423                 btrfs_queue_ordered_fn(ordered);
 424         return ret;
 425 }
 426
 427 /*
 428  * Mark all ordered extents io inside the specified range finished.
 429  *
 430  * @page:        The involved page for the operation.
 431  *               For uncompressed buffered IO, the page status also needs to be
 432  *               updated to indicate whether the pending ordered io is finished.
 433  *               Can be NULL for direct IO and compressed write.
 434  *               For these cases, callers are ensured they won't execute the
 435  *               endio function twice.
 436  *
 437  * This function is called for endio, thus the range must have ordered
 438  * extent(s) covering it.
 439  */
 440 void btrfs_mark_ordered_io_finished(struct btrfs_inode *inode,
 441                                     struct page *page, u64 file_offset,
 442                                     u64 num_bytes, bool uptodate)
 443 {
 444         struct rb_node *node;
 445         struct btrfs_ordered_extent *entry = NULL;
 446         unsigned long flags;
 447         u64 cur = file_offset;
 448
 449         trace_btrfs_writepage_end_io_hook(inode, file_offset,
 450                                           file_offset + num_bytes - 1,
 451                                           uptodate);
 452
 453         spin_lock_irqsave(&inode->ordered_tree_lock, flags);
 454         while (cur < file_offset + num_bytes) {
 455                 u64 entry_end;
 456                 u64 end;
 457                 u32 len;
 458
 459                 node = ordered_tree_search(inode, cur);
 460                 /* No ordered extents at all */
 461                 if (!node)
 462                         break;
 463
 464                 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 465                 entry_end = entry->file_offset + entry->num_bytes;
 466                 /*
 467                  * |<-- OE --->|  |
 468                  *                cur
 469                  * Go to next OE.
 470                  */
 471                 if (cur >= entry_end) {
 472                         node = rb_next(node);
 473                         /* No more ordered extents, exit */
 474                         if (!node)
 475                                 break;
 476                         entry = rb_entry(node, struct btrfs_ordered_extent,
 477                                          rb_node);
 478
 479                         /* Go to next ordered extent and continue */
 480                         cur = entry->file_offset;
 481                         continue;
 482                 }
 483                 /*
 484                  * |    |<--- OE --->|
 485                  * cur
 486                  * Go to the start of OE.
 487                  */
 488                 if (cur < entry->file_offset) {
 489                         cur = entry->file_offset;
 490                         continue;
 491                 }
 492
 493                 /*
 494                  * Now we are definitely inside one ordered extent.
 495                  *
 496                  * |<--- OE --->|
 497                  *      |
 498                  *      cur
 499                  */
 500                 end = min(entry->file_offset + entry->num_bytes,
 501                           file_offset + num_bytes) - 1;
 502                 ASSERT(end + 1 - cur < U32_MAX);
 503                 len = end + 1 - cur;
 504
 505                 if (can_finish_ordered_extent(entry, page, cur, len, uptodate)) {
 506                         spin_unlock_irqrestore(&inode->ordered_tree_lock, flags);
 507                         btrfs_queue_ordered_fn(entry);
 508                         spin_lock_irqsave(&inode->ordered_tree_lock, flags);
 509                 }
 510                 cur += len;
 511         }
 512         spin_unlock_irqrestore(&inode->ordered_tree_lock, flags);
 513 }
 514
 515 /*
 516  * Finish IO for one ordered extent across a given range.  The range can only
 517  * contain one ordered extent.
 518  *
 519  * @cached:      The cached ordered extent. If not NULL, we can skip the tree
 520  *               search and use the ordered extent directly.
 521  *               Will be also used to store the finished ordered extent.
 522  * @file_offset: File offset for the finished IO
 523  * @io_size:     Length of the finish IO range
 524  *
 525  * Return true if the ordered extent is finished in the range, and update
 526  * @cached.
 527  * Return false otherwise.
 528  *
 529  * NOTE: The range can NOT cross multiple ordered extents.
 530  * Thus caller should ensure the range doesn't cross ordered extents.
 531  */
 532 bool btrfs_dec_test_ordered_pending(struct btrfs_inode *inode,
 533                                     struct btrfs_ordered_extent **cached,
 534                                     u64 file_offset, u64 io_size)
 535 {
 536         struct rb_node *node;
 537         struct btrfs_ordered_extent *entry = NULL;
 538         unsigned long flags;
 539         bool finished = false;
 540
 541         spin_lock_irqsave(&inode->ordered_tree_lock, flags);
 542         if (cached && *cached) {
 543                 entry = *cached;
 544                 goto have_entry;
 545         }
 546
 547         node = ordered_tree_search(inode, file_offset);
 548         if (!node)
 549                 goto out;
 550
 551         entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 552 have_entry:
 553         if (!in_range(file_offset, entry->file_offset, entry->num_bytes))
 554                 goto out;
 555
 556         if (io_size > entry->bytes_left)
 557                 btrfs_crit(inode->root->fs_info,
 558                            "bad ordered accounting left %llu size %llu",
 559                        entry->bytes_left, io_size);
 560
 561         entry->bytes_left -= io_size;
 562
 563         if (entry->bytes_left == 0) {
 564                 /*
 565                  * Ensure only one caller can set the flag and finished_ret
 566                  * accordingly
 567                  */
 568                 finished = !test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);
 569                 /* test_and_set_bit implies a barrier */
 570                 cond_wake_up_nomb(&entry->wait);
 571         }
 572 out:
 573         if (finished && cached && entry) {
 574                 *cached = entry;
 575                 refcount_inc(&entry->refs);
 576                 trace_btrfs_ordered_extent_dec_test_pending(inode, entry);
 577         }
 578         spin_unlock_irqrestore(&inode->ordered_tree_lock, flags);
 579         return finished;
 580 }
 581
 582 /*
 583  * used to drop a reference on an ordered extent.  This will free
 584  * the extent if the last reference is dropped
 585  */
 586 void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry)
 587 {
 588         struct list_head *cur;
 589         struct btrfs_ordered_sum *sum;
 590
 591         trace_btrfs_ordered_extent_put(BTRFS_I(entry->inode), entry);
 592
 593         if (refcount_dec_and_test(&entry->refs)) {
 594                 ASSERT(list_empty(&entry->root_extent_list));
 595                 ASSERT(list_empty(&entry->log_list));
 596                 ASSERT(RB_EMPTY_NODE(&entry->rb_node));
 597                 if (entry->inode)
 598                         btrfs_add_delayed_iput(BTRFS_I(entry->inode));
 599                 while (!list_empty(&entry->list)) {
 600                         cur = entry->list.next;
 601                         sum = list_entry(cur, struct btrfs_ordered_sum, list);
 602                         list_del(&sum->list);
 603                         kvfree(sum);
 604                 }
 605                 kmem_cache_free(btrfs_ordered_extent_cache, entry);
 606         }
 607 }
 608
 609 /*
 610  * remove an ordered extent from the tree.  No references are dropped
 611  * and waiters are woken up.
 612  */
 613 void btrfs_remove_ordered_extent(struct btrfs_inode *btrfs_inode,
 614                                  struct btrfs_ordered_extent *entry)
 615 {
 616         struct btrfs_root *root = btrfs_inode->root;
 617         struct btrfs_fs_info *fs_info = root->fs_info;
 618         struct rb_node *node;
 619         bool pending;
 620         bool freespace_inode;
 621
 622         /*
 623          * If this is a free space inode the thread has not acquired the ordered
 624          * extents lockdep map.
 625          */
 626         freespace_inode = btrfs_is_free_space_inode(btrfs_inode);
 627
 628         btrfs_lockdep_acquire(fs_info, btrfs_trans_pending_ordered);
 629         /* This is paired with btrfs_alloc_ordered_extent. */
 630         spin_lock(&btrfs_inode->lock);
 631         btrfs_mod_outstanding_extents(btrfs_inode, -1);
 632         spin_unlock(&btrfs_inode->lock);
 633         if (root != fs_info->tree_root) {
 634                 u64 release;
 635
 636                 if (test_bit(BTRFS_ORDERED_ENCODED, &entry->flags))
 637                         release = entry->disk_num_bytes;
 638                 else
 639                         release = entry->num_bytes;
 640                 btrfs_delalloc_release_metadata(btrfs_inode, release,
 641                                                 test_bit(BTRFS_ORDERED_IOERR,
 642                                                          &entry->flags));
 643         }
 644
 645         percpu_counter_add_batch(&fs_info->ordered_bytes, -entry->num_bytes,
 646                                  fs_info->delalloc_batch);
 647
 648         spin_lock_irq(&btrfs_inode->ordered_tree_lock);
 649         node = &entry->rb_node;
 650         rb_erase(node, &btrfs_inode->ordered_tree);
 651         RB_CLEAR_NODE(node);
 652         if (btrfs_inode->ordered_tree_last == node)
 653                 btrfs_inode->ordered_tree_last = NULL;
 654         set_bit(BTRFS_ORDERED_COMPLETE, &entry->flags);
 655         pending = test_and_clear_bit(BTRFS_ORDERED_PENDING, &entry->flags);
 656         spin_unlock_irq(&btrfs_inode->ordered_tree_lock);
 657
 658         /*
 659          * The current running transaction is waiting on us, we need to let it
 660          * know that we're complete and wake it up.
 661          */
 662         if (pending) {
 663                 struct btrfs_transaction *trans;
 664
 665                 /*
 666                  * The checks for trans are just a formality, it should be set,
 667                  * but if it isn't we don't want to deref/assert under the spin
 668                  * lock, so be nice and check if trans is set, but ASSERT() so
 669                  * if it isn't set a developer will notice.
 670                  */
 671                 spin_lock(&fs_info->trans_lock);
 672                 trans = fs_info->running_transaction;
 673                 if (trans)
 674                         refcount_inc(&trans->use_count);
 675                 spin_unlock(&fs_info->trans_lock);
 676
 677                 ASSERT(trans || BTRFS_FS_ERROR(fs_info));
 678                 if (trans) {
 679                         if (atomic_dec_and_test(&trans->pending_ordered))
 680                                 wake_up(&trans->pending_wait);
 681                         btrfs_put_transaction(trans);
 682                 }
 683         }
 684
 685         btrfs_lockdep_release(fs_info, btrfs_trans_pending_ordered);
 686
 687         spin_lock(&root->ordered_extent_lock);
 688         list_del_init(&entry->root_extent_list);
 689         root->nr_ordered_extents--;
 690
 691         trace_btrfs_ordered_extent_remove(btrfs_inode, entry);
 692
 693         if (!root->nr_ordered_extents) {
 694                 spin_lock(&fs_info->ordered_root_lock);
 695                 BUG_ON(list_empty(&root->ordered_root));
 696                 list_del_init(&root->ordered_root);
 697                 spin_unlock(&fs_info->ordered_root_lock);
 698         }
 699         spin_unlock(&root->ordered_extent_lock);
 700         wake_up(&entry->wait);
 701         if (!freespace_inode)
 702                 btrfs_lockdep_release(fs_info, btrfs_ordered_extent);
 703 }
 704
 705 static void btrfs_run_ordered_extent_work(struct btrfs_work *work)
 706 {
 707         struct btrfs_ordered_extent *ordered;
 708
 709         ordered = container_of(work, struct btrfs_ordered_extent, flush_work);
 710         btrfs_start_ordered_extent(ordered);
 711         complete(&ordered->completion);
 712 }
 713
 714 /*
 715  * wait for all the ordered extents in a root.  This is done when balancing
 716  * space between drives.
 717  */
 718 u64 btrfs_wait_ordered_extents(struct btrfs_root *root, u64 nr,
 719                                const u64 range_start, const u64 range_len)
 720 {
 721         struct btrfs_fs_info *fs_info = root->fs_info;
 722         LIST_HEAD(splice);
 723         LIST_HEAD(skipped);
 724         LIST_HEAD(works);
 725         struct btrfs_ordered_extent *ordered, *next;
 726         u64 count = 0;
 727         const u64 range_end = range_start + range_len;
 728
 729         mutex_lock(&root->ordered_extent_mutex);
 730         spin_lock(&root->ordered_extent_lock);
 731         list_splice_init(&root->ordered_extents, &splice);
 732         while (!list_empty(&splice) && nr) {
 733                 ordered = list_first_entry(&splice, struct btrfs_ordered_extent,
 734                                            root_extent_list);
 735
 736                 if (range_end <= ordered->disk_bytenr ||
 737                     ordered->disk_bytenr + ordered->disk_num_bytes <= range_start) {
 738                         list_move_tail(&ordered->root_extent_list, &skipped);
 739                         cond_resched_lock(&root->ordered_extent_lock);
 740                         continue;
 741                 }
 742
 743                 list_move_tail(&ordered->root_extent_list,
 744                                &root->ordered_extents);
 745                 refcount_inc(&ordered->refs);
 746                 spin_unlock(&root->ordered_extent_lock);
 747
 748                 btrfs_init_work(&ordered->flush_work,
 749                                 btrfs_run_ordered_extent_work, NULL);
 750                 list_add_tail(&ordered->work_list, &works);
 751                 btrfs_queue_work(fs_info->flush_workers, &ordered->flush_work);
 752
 753                 cond_resched();
 754                 spin_lock(&root->ordered_extent_lock);
 755                 if (nr != U64_MAX)
 756                         nr--;
 757                 count++;
 758         }
 759         list_splice_tail(&skipped, &root->ordered_extents);
 760         list_splice_tail(&splice, &root->ordered_extents);
 761         spin_unlock(&root->ordered_extent_lock);
 762
 763         list_for_each_entry_safe(ordered, next, &works, work_list) {
 764                 list_del_init(&ordered->work_list);
 765                 wait_for_completion(&ordered->completion);
 766                 btrfs_put_ordered_extent(ordered);
 767                 cond_resched();
 768         }
 769         mutex_unlock(&root->ordered_extent_mutex);
 770
 771         return count;
 772 }
 773
 774 void btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, u64 nr,
 775                              const u64 range_start, const u64 range_len)
 776 {
 777         struct btrfs_root *root;
 778         LIST_HEAD(splice);
 779         u64 done;
 780
 781         mutex_lock(&fs_info->ordered_operations_mutex);
 782         spin_lock(&fs_info->ordered_root_lock);
 783         list_splice_init(&fs_info->ordered_roots, &splice);
 784         while (!list_empty(&splice) && nr) {
 785                 root = list_first_entry(&splice, struct btrfs_root,
 786                                         ordered_root);
 787                 root = btrfs_grab_root(root);
 788                 BUG_ON(!root);
 789                 list_move_tail(&root->ordered_root,
 790                                &fs_info->ordered_roots);
 791                 spin_unlock(&fs_info->ordered_root_lock);
 792
 793                 done = btrfs_wait_ordered_extents(root, nr,
 794                                                   range_start, range_len);
 795                 btrfs_put_root(root);
 796
 797                 spin_lock(&fs_info->ordered_root_lock);
 798                 if (nr != U64_MAX) {
 799                         nr -= done;
 800                 }
 801         }
 802         list_splice_tail(&splice, &fs_info->ordered_roots);
 803         spin_unlock(&fs_info->ordered_root_lock);
 804         mutex_unlock(&fs_info->ordered_operations_mutex);
 805 }
 806
 807 /*
 808  * Start IO and wait for a given ordered extent to finish.
 809  *
 810  * Wait on page writeback for all the pages in the extent and the IO completion
 811  * code to insert metadata into the btree corresponding to the extent.
 812  */
 813 void btrfs_start_ordered_extent(struct btrfs_ordered_extent *entry)
 814 {
 815         u64 start = entry->file_offset;
 816         u64 end = start + entry->num_bytes - 1;
 817         struct btrfs_inode *inode = BTRFS_I(entry->inode);
 818         bool freespace_inode;
 819
 820         trace_btrfs_ordered_extent_start(inode, entry);
 821
 822         /*
 823          * If this is a free space inode do not take the ordered extents lockdep
 824          * map.
 825          */
 826         freespace_inode = btrfs_is_free_space_inode(inode);
 827
 828         /*
 829          * pages in the range can be dirty, clean or writeback.  We
 830          * start IO on any dirty ones so the wait doesn't stall waiting
 831          * for the flusher thread to find them
 832          */
 833         if (!test_bit(BTRFS_ORDERED_DIRECT, &entry->flags))
 834                 filemap_fdatawrite_range(inode->vfs_inode.i_mapping, start, end);
 835
 836         if (!freespace_inode)
 837                 btrfs_might_wait_for_event(inode->root->fs_info, btrfs_ordered_extent);
 838         wait_event(entry->wait, test_bit(BTRFS_ORDERED_COMPLETE, &entry->flags));
 839 }
 840
 841 /*
 842  * Used to wait on ordered extents across a large range of bytes.
 843  */
 844 int btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len)
 845 {
 846         int ret = 0;
 847         int ret_wb = 0;
 848         u64 end;
 849         u64 orig_end;
 850         struct btrfs_ordered_extent *ordered;
 851
 852         if (start + len < start) {
 853                 orig_end = OFFSET_MAX;
 854         } else {
 855                 orig_end = start + len - 1;
 856                 if (orig_end > OFFSET_MAX)
 857                         orig_end = OFFSET_MAX;
 858         }
 859
 860         /* start IO across the range first to instantiate any delalloc
 861          * extents
 862          */
 863         ret = btrfs_fdatawrite_range(inode, start, orig_end);
 864         if (ret)
 865                 return ret;
 866
 867         /*
 868          * If we have a writeback error don't return immediately. Wait first
 869          * for any ordered extents that haven't completed yet. This is to make
 870          * sure no one can dirty the same page ranges and call writepages()
 871          * before the ordered extents complete - to avoid failures (-EEXIST)
 872          * when adding the new ordered extents to the ordered tree.
 873          */
 874         ret_wb = filemap_fdatawait_range(inode->i_mapping, start, orig_end);
 875
 876         end = orig_end;
 877         while (1) {
 878                 ordered = btrfs_lookup_first_ordered_extent(BTRFS_I(inode), end);
 879                 if (!ordered)
 880                         break;
 881                 if (ordered->file_offset > orig_end) {
 882                         btrfs_put_ordered_extent(ordered);
 883                         break;
 884                 }
 885                 if (ordered->file_offset + ordered->num_bytes <= start) {
 886                         btrfs_put_ordered_extent(ordered);
 887                         break;
 888                 }
 889                 btrfs_start_ordered_extent(ordered);
 890                 end = ordered->file_offset;
 891                 /*
 892                  * If the ordered extent had an error save the error but don't
 893                  * exit without waiting first for all other ordered extents in
 894                  * the range to complete.
 895                  */
 896                 if (test_bit(BTRFS_ORDERED_IOERR, &ordered->flags))
 897                         ret = -EIO;
 898                 btrfs_put_ordered_extent(ordered);
 899                 if (end == 0 || end == start)
 900                         break;
 901                 end--;
 902         }
 903         return ret_wb ? ret_wb : ret;
 904 }
 905
 906 /*
 907  * find an ordered extent corresponding to file_offset.  return NULL if
 908  * nothing is found, otherwise take a reference on the extent and return it
 909  */
 910 struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct btrfs_inode *inode,
 911                                                          u64 file_offset)
 912 {
 913         struct rb_node *node;
 914         struct btrfs_ordered_extent *entry = NULL;
 915         unsigned long flags;
 916
 917         spin_lock_irqsave(&inode->ordered_tree_lock, flags);
 918         node = ordered_tree_search(inode, file_offset);
 919         if (!node)
 920                 goto out;
 921
 922         entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 923         if (!in_range(file_offset, entry->file_offset, entry->num_bytes))
 924                 entry = NULL;
 925         if (entry) {
 926                 refcount_inc(&entry->refs);
 927                 trace_btrfs_ordered_extent_lookup(inode, entry);
 928         }
 929 out:
 930         spin_unlock_irqrestore(&inode->ordered_tree_lock, flags);
 931         return entry;
 932 }
 933
 934 /* Since the DIO code tries to lock a wide area we need to look for any ordered
 935  * extents that exist in the range, rather than just the start of the range.
 936  */
 937 struct btrfs_ordered_extent *btrfs_lookup_ordered_range(
 938                 struct btrfs_inode *inode, u64 file_offset, u64 len)
 939 {
 940         struct rb_node *node;
 941         struct btrfs_ordered_extent *entry = NULL;
 942
 943         spin_lock_irq(&inode->ordered_tree_lock);
 944         node = ordered_tree_search(inode, file_offset);
 945         if (!node) {
 946                 node = ordered_tree_search(inode, file_offset + len);
 947                 if (!node)
 948                         goto out;
 949         }
 950
 951         while (1) {
 952                 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 953                 if (range_overlaps(entry, file_offset, len))
 954                         break;
 955
 956                 if (entry->file_offset >= file_offset + len) {
 957                         entry = NULL;
 958                         break;
 959                 }
 960                 entry = NULL;
 961                 node = rb_next(node);
 962                 if (!node)
 963                         break;
 964         }
 965 out:
 966         if (entry) {
 967                 refcount_inc(&entry->refs);
 968                 trace_btrfs_ordered_extent_lookup_range(inode, entry);
 969         }
 970         spin_unlock_irq(&inode->ordered_tree_lock);
 971         return entry;
 972 }
 973
 974 /*
 975  * Adds all ordered extents to the given list. The list ends up sorted by the
 976  * file_offset of the ordered extents.
 977  */
 978 void btrfs_get_ordered_extents_for_logging(struct btrfs_inode *inode,
 979                                            struct list_head *list)
 980 {
 981         struct rb_node *n;
 982
 983         ASSERT(inode_is_locked(&inode->vfs_inode));
 984
 985         spin_lock_irq(&inode->ordered_tree_lock);
 986         for (n = rb_first(&inode->ordered_tree); n; n = rb_next(n)) {
 987                 struct btrfs_ordered_extent *ordered;
 988
 989                 ordered = rb_entry(n, struct btrfs_ordered_extent, rb_node);
 990
 991                 if (test_bit(BTRFS_ORDERED_LOGGED, &ordered->flags))
 992                         continue;
 993
 994                 ASSERT(list_empty(&ordered->log_list));
 995                 list_add_tail(&ordered->log_list, list);
 996                 refcount_inc(&ordered->refs);
 997                 trace_btrfs_ordered_extent_lookup_for_logging(inode, ordered);
 998         }
 999         spin_unlock_irq(&inode->ordered_tree_lock);
1000 }
1001
1002 /*
1003  * lookup and return any extent before 'file_offset'.  NULL is returned
1004  * if none is found
1005  */
1006 struct btrfs_ordered_extent *
1007 btrfs_lookup_first_ordered_extent(struct btrfs_inode *inode, u64 file_offset)
1008 {
1009         struct rb_node *node;
1010         struct btrfs_ordered_extent *entry = NULL;
1011
1012         spin_lock_irq(&inode->ordered_tree_lock);
1013         node = ordered_tree_search(inode, file_offset);
1014         if (!node)
1015                 goto out;
1016
1017         entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
1018         refcount_inc(&entry->refs);
1019         trace_btrfs_ordered_extent_lookup_first(inode, entry);
1020 out:
1021         spin_unlock_irq(&inode->ordered_tree_lock);
1022         return entry;
1023 }
1024
1025 /*
1026  * Lookup the first ordered extent that overlaps the range
1027  * [@file_offset, @file_offset + @len).
1028  *
1029  * The difference between this and btrfs_lookup_first_ordered_extent() is
1030  * that this one won't return any ordered extent that does not overlap the range.
1031  * And the difference against btrfs_lookup_ordered_extent() is, this function
1032  * ensures the first ordered extent gets returned.
1033  */
1034 struct btrfs_ordered_extent *btrfs_lookup_first_ordered_range(
1035                         struct btrfs_inode *inode, u64 file_offset, u64 len)
1036 {
1037         struct rb_node *node;
1038         struct rb_node *cur;
1039         struct rb_node *prev;
1040         struct rb_node *next;
1041         struct btrfs_ordered_extent *entry = NULL;
1042
1043         spin_lock_irq(&inode->ordered_tree_lock);
1044         node = inode->ordered_tree.rb_node;
1045         /*
1046          * Here we don't want to use tree_search() which will use tree->last
1047          * and screw up the search order.
1048          * And __tree_search() can't return the adjacent ordered extents
1049          * either, thus here we do our own search.
1050          */
1051         while (node) {
1052                 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
1053
1054                 if (file_offset < entry->file_offset) {
1055                         node = node->rb_left;
1056                 } else if (file_offset >= entry_end(entry)) {
1057                         node = node->rb_right;
1058                 } else {
1059                         /*
1060                          * Direct hit, got an ordered extent that starts at
1061                          * @file_offset
1062                          */
1063                         goto out;
1064                 }
1065         }
1066         if (!entry) {
1067                 /* Empty tree */
1068                 goto out;
1069         }
1070
1071         cur = &entry->rb_node;
1072         /* We got an entry around @file_offset, check adjacent entries */
1073         if (entry->file_offset < file_offset) {
1074                 prev = cur;
1075                 next = rb_next(cur);
1076         } else {
1077                 prev = rb_prev(cur);
1078                 next = cur;
1079         }
1080         if (prev) {
1081                 entry = rb_entry(prev, struct btrfs_ordered_extent, rb_node);
1082                 if (range_overlaps(entry, file_offset, len))
1083                         goto out;
1084         }
1085         if (next) {
1086                 entry = rb_entry(next, struct btrfs_ordered_extent, rb_node);
1087                 if (range_overlaps(entry, file_offset, len))
1088                         goto out;
1089         }
1090         /* No ordered extent in the range */
1091         entry = NULL;
1092 out:
1093         if (entry) {
1094                 refcount_inc(&entry->refs);
1095                 trace_btrfs_ordered_extent_lookup_first_range(inode, entry);
1096         }
1097
1098         spin_unlock_irq(&inode->ordered_tree_lock);
1099         return entry;
1100 }
1101
1102 /*
1103  * Lock the passed range and ensures all pending ordered extents in it are run
1104  * to completion.
1105  *
1106  * @inode:        Inode whose ordered tree is to be searched
1107  * @start:        Beginning of range to flush
1108  * @end:          Last byte of range to lock
1109  * @cached_state: If passed, will return the extent state responsible for the
1110  *                locked range. It's the caller's responsibility to free the
1111  *                cached state.
1112  *
1113  * Always return with the given range locked, ensuring after it's called no
1114  * order extent can be pending.
1115  */
1116 void btrfs_lock_and_flush_ordered_range(struct btrfs_inode *inode, u64 start,
1117                                         u64 end,
1118                                         struct extent_state **cached_state)
1119 {
1120         struct btrfs_ordered_extent *ordered;
1121         struct extent_state *cache = NULL;
1122         struct extent_state **cachedp = &cache;
1123
1124         if (cached_state)
1125                 cachedp = cached_state;
1126
1127         while (1) {
1128                 lock_extent(&inode->io_tree, start, end, cachedp);
1129                 ordered = btrfs_lookup_ordered_range(inode, start,
1130                                                      end - start + 1);
1131                 if (!ordered) {
1132                         /*
1133                          * If no external cached_state has been passed then
1134                          * decrement the extra ref taken for cachedp since we
1135                          * aren't exposing it outside of this function
1136                          */
1137                         if (!cached_state)
1138                                 refcount_dec(&cache->refs);
1139                         break;
1140                 }
1141                 unlock_extent(&inode->io_tree, start, end, cachedp);
1142                 btrfs_start_ordered_extent(ordered);
1143                 btrfs_put_ordered_extent(ordered);
1144         }
1145 }
1146
1147 /*
1148  * Lock the passed range and ensure all pending ordered extents in it are run
1149  * to completion in nowait mode.
1150  *
1151  * Return true if btrfs_lock_ordered_range does not return any extents,
1152  * otherwise false.
1153  */
1154 bool btrfs_try_lock_ordered_range(struct btrfs_inode *inode, u64 start, u64 end,
1155                                   struct extent_state **cached_state)
1156 {
1157         struct btrfs_ordered_extent *ordered;
1158
1159         if (!try_lock_extent(&inode->io_tree, start, end, cached_state))
1160                 return false;
1161
1162         ordered = btrfs_lookup_ordered_range(inode, start, end - start + 1);
1163         if (!ordered)
1164                 return true;
1165
1166         btrfs_put_ordered_extent(ordered);
1167         unlock_extent(&inode->io_tree, start, end, cached_state);
1168
1169         return false;
1170 }
1171
1172 /* Split out a new ordered extent for this first @len bytes of @ordered. */
1173 struct btrfs_ordered_extent *btrfs_split_ordered_extent(
1174                         struct btrfs_ordered_extent *ordered, u64 len)
1175 {
1176         struct btrfs_inode *inode = BTRFS_I(ordered->inode);
1177         struct btrfs_root *root = inode->root;
1178         struct btrfs_fs_info *fs_info = root->fs_info;
1179         u64 file_offset = ordered->file_offset;
1180         u64 disk_bytenr = ordered->disk_bytenr;
1181         unsigned long flags = ordered->flags;
1182         struct btrfs_ordered_sum *sum, *tmpsum;
1183         struct btrfs_ordered_extent *new;
1184         struct rb_node *node;
1185         u64 offset = 0;
1186
1187         trace_btrfs_ordered_extent_split(inode, ordered);
1188
1189         ASSERT(!(flags & (1U << BTRFS_ORDERED_COMPRESSED)));
1190
1191         /*
1192          * The entire bio must be covered by the ordered extent, but we can't
1193          * reduce the original extent to a zero length either.
1194          */
1195         if (WARN_ON_ONCE(len >= ordered->num_bytes))
1196                 return ERR_PTR(-EINVAL);
1197         /* We cannot split partially completed ordered extents. */
1198         if (ordered->bytes_left) {
1199                 ASSERT(!(flags & ~BTRFS_ORDERED_TYPE_FLAGS));
1200                 if (WARN_ON_ONCE(ordered->bytes_left != ordered->disk_num_bytes))
1201                         return ERR_PTR(-EINVAL);
1202         }
1203         /* We cannot split a compressed ordered extent. */
1204         if (WARN_ON_ONCE(ordered->disk_num_bytes != ordered->num_bytes))
1205                 return ERR_PTR(-EINVAL);
1206
1207         new = alloc_ordered_extent(inode, file_offset, len, len, disk_bytenr,
1208                                    len, 0, flags, ordered->compress_type);
1209         if (IS_ERR(new))
1210                 return new;
1211
1212         /* One ref for the tree. */
1213         refcount_inc(&new->refs);
1214
1215         spin_lock_irq(&root->ordered_extent_lock);
1216         spin_lock(&inode->ordered_tree_lock);
1217         /* Remove from tree once */
1218         node = &ordered->rb_node;
1219         rb_erase(node, &inode->ordered_tree);
1220         RB_CLEAR_NODE(node);
1221         if (inode->ordered_tree_last == node)
1222                 inode->ordered_tree_last = NULL;
1223
1224         ordered->file_offset += len;
1225         ordered->disk_bytenr += len;
1226         ordered->num_bytes -= len;
1227         ordered->disk_num_bytes -= len;
1228         ordered->ram_bytes -= len;
1229
1230         if (test_bit(BTRFS_ORDERED_IO_DONE, &ordered->flags)) {
1231                 ASSERT(ordered->bytes_left == 0);
1232                 new->bytes_left = 0;
1233         } else {
1234                 ordered->bytes_left -= len;
1235         }
1236
1237         if (test_bit(BTRFS_ORDERED_TRUNCATED, &ordered->flags)) {
1238                 if (ordered->truncated_len > len) {
1239                         ordered->truncated_len -= len;
1240                 } else {
1241                         new->truncated_len = ordered->truncated_len;
1242                         ordered->truncated_len = 0;
1243                 }
1244         }
1245
1246         list_for_each_entry_safe(sum, tmpsum, &ordered->list, list) {
1247                 if (offset == len)
1248                         break;
1249                 list_move_tail(&sum->list, &new->list);
1250                 offset += sum->len;
1251         }
1252
1253         /* Re-insert the node */
1254         node = tree_insert(&inode->ordered_tree, ordered->file_offset,
1255                            &ordered->rb_node);
1256         if (node)
1257                 btrfs_panic(fs_info, -EEXIST,
1258                         "zoned: inconsistency in ordered tree at offset %llu",
1259                         ordered->file_offset);
1260
1261         node = tree_insert(&inode->ordered_tree, new->file_offset, &new->rb_node);
1262         if (node)
1263                 btrfs_panic(fs_info, -EEXIST,
1264                         "zoned: inconsistency in ordered tree at offset %llu",
1265                         new->file_offset);
1266         spin_unlock(&inode->ordered_tree_lock);
1267
1268         list_add_tail(&new->root_extent_list, &root->ordered_extents);
1269         root->nr_ordered_extents++;
1270         spin_unlock_irq(&root->ordered_extent_lock);
1271         return new;
1272 }
1273
1274 int __init ordered_data_init(void)
1275 {
1276         btrfs_ordered_extent_cache = KMEM_CACHE(btrfs_ordered_extent, 0);
1277         if (!btrfs_ordered_extent_cache)
1278                 return -ENOMEM;
1279
1280         return 0;
1281 }
1282
1283 void __cold ordered_data_exit(void)
1284 {
1285         kmem_cache_destroy(btrfs_ordered_extent_cache);
1286 }