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