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