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  * @uptodate:    If the IO finishes without problem
 450  *
 451  * Return true if the ordered extent is finished in the range, and update
 452  * @cached.
 453  * Return false otherwise.
 454  *
 455  * NOTE: The range can NOT cross multiple ordered extents.
 456  * Thus caller should ensure the range doesn't cross ordered extents.
 457  */
 458 bool btrfs_dec_test_ordered_pending(struct btrfs_inode *inode,
 459                                     struct btrfs_ordered_extent **cached,
 460                                     u64 file_offset, u64 io_size, int uptodate)
 461 {
 462         struct btrfs_ordered_inode_tree *tree = &inode->ordered_tree;
 463         struct rb_node *node;
 464         struct btrfs_ordered_extent *entry = NULL;
 465         unsigned long flags;
 466         bool finished = false;
 467
 468         spin_lock_irqsave(&tree->lock, flags);
 469         if (cached && *cached) {
 470                 entry = *cached;
 471                 goto have_entry;
 472         }
 473
 474         node = tree_search(tree, file_offset);
 475         if (!node)
 476                 goto out;
 477
 478         entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 479 have_entry:
 480         if (!in_range(file_offset, entry->file_offset, entry->num_bytes))
 481                 goto out;
 482
 483         if (io_size > entry->bytes_left)
 484                 btrfs_crit(inode->root->fs_info,
 485                            "bad ordered accounting left %llu size %llu",
 486                        entry->bytes_left, io_size);
 487
 488         entry->bytes_left -= io_size;
 489         if (!uptodate)
 490                 set_bit(BTRFS_ORDERED_IOERR, &entry->flags);
 491
 492         if (entry->bytes_left == 0) {
 493                 /*
 494                  * Ensure only one caller can set the flag and finished_ret
 495                  * accordingly
 496                  */
 497                 finished = !test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);
 498                 /* test_and_set_bit implies a barrier */
 499                 cond_wake_up_nomb(&entry->wait);
 500         }
 501 out:
 502         if (finished && cached && entry) {
 503                 *cached = entry;
 504                 refcount_inc(&entry->refs);
 505         }
 506         spin_unlock_irqrestore(&tree->lock, flags);
 507         return finished;
 508 }
 509
 510 /*
 511  * used to drop a reference on an ordered extent.  This will free
 512  * the extent if the last reference is dropped
 513  */
 514 void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry)
 515 {
 516         struct list_head *cur;
 517         struct btrfs_ordered_sum *sum;
 518
 519         trace_btrfs_ordered_extent_put(BTRFS_I(entry->inode), entry);
 520
 521         if (refcount_dec_and_test(&entry->refs)) {
 522                 ASSERT(list_empty(&entry->root_extent_list));
 523                 ASSERT(list_empty(&entry->log_list));
 524                 ASSERT(RB_EMPTY_NODE(&entry->rb_node));
 525                 if (entry->inode)
 526                         btrfs_add_delayed_iput(entry->inode);
 527                 while (!list_empty(&entry->list)) {
 528                         cur = entry->list.next;
 529                         sum = list_entry(cur, struct btrfs_ordered_sum, list);
 530                         list_del(&sum->list);
 531                         kvfree(sum);
 532                 }
 533                 kmem_cache_free(btrfs_ordered_extent_cache, entry);
 534         }
 535 }
 536
 537 /*
 538  * remove an ordered extent from the tree.  No references are dropped
 539  * and waiters are woken up.
 540  */
 541 void btrfs_remove_ordered_extent(struct btrfs_inode *btrfs_inode,
 542                                  struct btrfs_ordered_extent *entry)
 543 {
 544         struct btrfs_ordered_inode_tree *tree;
 545         struct btrfs_root *root = btrfs_inode->root;
 546         struct btrfs_fs_info *fs_info = root->fs_info;
 547         struct rb_node *node;
 548         bool pending;
 549
 550         /* This is paired with btrfs_add_ordered_extent. */
 551         spin_lock(&btrfs_inode->lock);
 552         btrfs_mod_outstanding_extents(btrfs_inode, -1);
 553         spin_unlock(&btrfs_inode->lock);
 554         if (root != fs_info->tree_root)
 555                 btrfs_delalloc_release_metadata(btrfs_inode, entry->num_bytes,
 556                                                 false);
 557
 558         percpu_counter_add_batch(&fs_info->ordered_bytes, -entry->num_bytes,
 559                                  fs_info->delalloc_batch);
 560
 561         tree = &btrfs_inode->ordered_tree;
 562         spin_lock_irq(&tree->lock);
 563         node = &entry->rb_node;
 564         rb_erase(node, &tree->tree);
 565         RB_CLEAR_NODE(node);
 566         if (tree->last == node)
 567                 tree->last = NULL;
 568         set_bit(BTRFS_ORDERED_COMPLETE, &entry->flags);
 569         pending = test_and_clear_bit(BTRFS_ORDERED_PENDING, &entry->flags);
 570         spin_unlock_irq(&tree->lock);
 571
 572         /*
 573          * The current running transaction is waiting on us, we need to let it
 574          * know that we're complete and wake it up.
 575          */
 576         if (pending) {
 577                 struct btrfs_transaction *trans;
 578
 579                 /*
 580                  * The checks for trans are just a formality, it should be set,
 581                  * but if it isn't we don't want to deref/assert under the spin
 582                  * lock, so be nice and check if trans is set, but ASSERT() so
 583                  * if it isn't set a developer will notice.
 584                  */
 585                 spin_lock(&fs_info->trans_lock);
 586                 trans = fs_info->running_transaction;
 587                 if (trans)
 588                         refcount_inc(&trans->use_count);
 589                 spin_unlock(&fs_info->trans_lock);
 590
 591                 ASSERT(trans);
 592                 if (trans) {
 593                         if (atomic_dec_and_test(&trans->pending_ordered))
 594                                 wake_up(&trans->pending_wait);
 595                         btrfs_put_transaction(trans);
 596                 }
 597         }
 598
 599         spin_lock(&root->ordered_extent_lock);
 600         list_del_init(&entry->root_extent_list);
 601         root->nr_ordered_extents--;
 602
 603         trace_btrfs_ordered_extent_remove(btrfs_inode, entry);
 604
 605         if (!root->nr_ordered_extents) {
 606                 spin_lock(&fs_info->ordered_root_lock);
 607                 BUG_ON(list_empty(&root->ordered_root));
 608                 list_del_init(&root->ordered_root);
 609                 spin_unlock(&fs_info->ordered_root_lock);
 610         }
 611         spin_unlock(&root->ordered_extent_lock);
 612         wake_up(&entry->wait);
 613 }
 614
 615 static void btrfs_run_ordered_extent_work(struct btrfs_work *work)
 616 {
 617         struct btrfs_ordered_extent *ordered;
 618
 619         ordered = container_of(work, struct btrfs_ordered_extent, flush_work);
 620         btrfs_start_ordered_extent(ordered, 1);
 621         complete(&ordered->completion);
 622 }
 623
 624 /*
 625  * wait for all the ordered extents in a root.  This is done when balancing
 626  * space between drives.
 627  */
 628 u64 btrfs_wait_ordered_extents(struct btrfs_root *root, u64 nr,
 629                                const u64 range_start, const u64 range_len)
 630 {
 631         struct btrfs_fs_info *fs_info = root->fs_info;
 632         LIST_HEAD(splice);
 633         LIST_HEAD(skipped);
 634         LIST_HEAD(works);
 635         struct btrfs_ordered_extent *ordered, *next;
 636         u64 count = 0;
 637         const u64 range_end = range_start + range_len;
 638
 639         mutex_lock(&root->ordered_extent_mutex);
 640         spin_lock(&root->ordered_extent_lock);
 641         list_splice_init(&root->ordered_extents, &splice);
 642         while (!list_empty(&splice) && nr) {
 643                 ordered = list_first_entry(&splice, struct btrfs_ordered_extent,
 644                                            root_extent_list);
 645
 646                 if (range_end <= ordered->disk_bytenr ||
 647                     ordered->disk_bytenr + ordered->disk_num_bytes <= range_start) {
 648                         list_move_tail(&ordered->root_extent_list, &skipped);
 649                         cond_resched_lock(&root->ordered_extent_lock);
 650                         continue;
 651                 }
 652
 653                 list_move_tail(&ordered->root_extent_list,
 654                                &root->ordered_extents);
 655                 refcount_inc(&ordered->refs);
 656                 spin_unlock(&root->ordered_extent_lock);
 657
 658                 btrfs_init_work(&ordered->flush_work,
 659                                 btrfs_run_ordered_extent_work, NULL, NULL);
 660                 list_add_tail(&ordered->work_list, &works);
 661                 btrfs_queue_work(fs_info->flush_workers, &ordered->flush_work);
 662
 663                 cond_resched();
 664                 spin_lock(&root->ordered_extent_lock);
 665                 if (nr != U64_MAX)
 666                         nr--;
 667                 count++;
 668         }
 669         list_splice_tail(&skipped, &root->ordered_extents);
 670         list_splice_tail(&splice, &root->ordered_extents);
 671         spin_unlock(&root->ordered_extent_lock);
 672
 673         list_for_each_entry_safe(ordered, next, &works, work_list) {
 674                 list_del_init(&ordered->work_list);
 675                 wait_for_completion(&ordered->completion);
 676                 btrfs_put_ordered_extent(ordered);
 677                 cond_resched();
 678         }
 679         mutex_unlock(&root->ordered_extent_mutex);
 680
 681         return count;
 682 }
 683
 684 void btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, u64 nr,
 685                              const u64 range_start, const u64 range_len)
 686 {
 687         struct btrfs_root *root;
 688         struct list_head splice;
 689         u64 done;
 690
 691         INIT_LIST_HEAD(&splice);
 692
 693         mutex_lock(&fs_info->ordered_operations_mutex);
 694         spin_lock(&fs_info->ordered_root_lock);
 695         list_splice_init(&fs_info->ordered_roots, &splice);
 696         while (!list_empty(&splice) && nr) {
 697                 root = list_first_entry(&splice, struct btrfs_root,
 698                                         ordered_root);
 699                 root = btrfs_grab_root(root);
 700                 BUG_ON(!root);
 701                 list_move_tail(&root->ordered_root,
 702                                &fs_info->ordered_roots);
 703                 spin_unlock(&fs_info->ordered_root_lock);
 704
 705                 done = btrfs_wait_ordered_extents(root, nr,
 706                                                   range_start, range_len);
 707                 btrfs_put_root(root);
 708
 709                 spin_lock(&fs_info->ordered_root_lock);
 710                 if (nr != U64_MAX) {
 711                         nr -= done;
 712                 }
 713         }
 714         list_splice_tail(&splice, &fs_info->ordered_roots);
 715         spin_unlock(&fs_info->ordered_root_lock);
 716         mutex_unlock(&fs_info->ordered_operations_mutex);
 717 }
 718
 719 /*
 720  * Used to start IO or wait for a given ordered extent to finish.
 721  *
 722  * If wait is one, this effectively waits on page writeback for all the pages
 723  * in the extent, and it waits on the io completion code to insert
 724  * metadata into the btree corresponding to the extent
 725  */
 726 void btrfs_start_ordered_extent(struct btrfs_ordered_extent *entry, int wait)
 727 {
 728         u64 start = entry->file_offset;
 729         u64 end = start + entry->num_bytes - 1;
 730         struct btrfs_inode *inode = BTRFS_I(entry->inode);
 731
 732         trace_btrfs_ordered_extent_start(inode, entry);
 733
 734         /*
 735          * pages in the range can be dirty, clean or writeback.  We
 736          * start IO on any dirty ones so the wait doesn't stall waiting
 737          * for the flusher thread to find them
 738          */
 739         if (!test_bit(BTRFS_ORDERED_DIRECT, &entry->flags))
 740                 filemap_fdatawrite_range(inode->vfs_inode.i_mapping, start, end);
 741         if (wait) {
 742                 wait_event(entry->wait, test_bit(BTRFS_ORDERED_COMPLETE,
 743                                                  &entry->flags));
 744         }
 745 }
 746
 747 /*
 748  * Used to wait on ordered extents across a large range of bytes.
 749  */
 750 int btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len)
 751 {
 752         int ret = 0;
 753         int ret_wb = 0;
 754         u64 end;
 755         u64 orig_end;
 756         struct btrfs_ordered_extent *ordered;
 757
 758         if (start + len < start) {
 759                 orig_end = INT_LIMIT(loff_t);
 760         } else {
 761                 orig_end = start + len - 1;
 762                 if (orig_end > INT_LIMIT(loff_t))
 763                         orig_end = INT_LIMIT(loff_t);
 764         }
 765
 766         /* start IO across the range first to instantiate any delalloc
 767          * extents
 768          */
 769         ret = btrfs_fdatawrite_range(inode, start, orig_end);
 770         if (ret)
 771                 return ret;
 772
 773         /*
 774          * If we have a writeback error don't return immediately. Wait first
 775          * for any ordered extents that haven't completed yet. This is to make
 776          * sure no one can dirty the same page ranges and call writepages()
 777          * before the ordered extents complete - to avoid failures (-EEXIST)
 778          * when adding the new ordered extents to the ordered tree.
 779          */
 780         ret_wb = filemap_fdatawait_range(inode->i_mapping, start, orig_end);
 781
 782         end = orig_end;
 783         while (1) {
 784                 ordered = btrfs_lookup_first_ordered_extent(BTRFS_I(inode), end);
 785                 if (!ordered)
 786                         break;
 787                 if (ordered->file_offset > orig_end) {
 788                         btrfs_put_ordered_extent(ordered);
 789                         break;
 790                 }
 791                 if (ordered->file_offset + ordered->num_bytes <= start) {
 792                         btrfs_put_ordered_extent(ordered);
 793                         break;
 794                 }
 795                 btrfs_start_ordered_extent(ordered, 1);
 796                 end = ordered->file_offset;
 797                 /*
 798                  * If the ordered extent had an error save the error but don't
 799                  * exit without waiting first for all other ordered extents in
 800                  * the range to complete.
 801                  */
 802                 if (test_bit(BTRFS_ORDERED_IOERR, &ordered->flags))
 803                         ret = -EIO;
 804                 btrfs_put_ordered_extent(ordered);
 805                 if (end == 0 || end == start)
 806                         break;
 807                 end--;
 808         }
 809         return ret_wb ? ret_wb : ret;
 810 }
 811
 812 /*
 813  * find an ordered extent corresponding to file_offset.  return NULL if
 814  * nothing is found, otherwise take a reference on the extent and return it
 815  */
 816 struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct btrfs_inode *inode,
 817                                                          u64 file_offset)
 818 {
 819         struct btrfs_ordered_inode_tree *tree;
 820         struct rb_node *node;
 821         struct btrfs_ordered_extent *entry = NULL;
 822         unsigned long flags;
 823
 824         tree = &inode->ordered_tree;
 825         spin_lock_irqsave(&tree->lock, flags);
 826         node = tree_search(tree, file_offset);
 827         if (!node)
 828                 goto out;
 829
 830         entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 831         if (!in_range(file_offset, entry->file_offset, entry->num_bytes))
 832                 entry = NULL;
 833         if (entry)
 834                 refcount_inc(&entry->refs);
 835 out:
 836         spin_unlock_irqrestore(&tree->lock, flags);
 837         return entry;
 838 }
 839
 840 /* Since the DIO code tries to lock a wide area we need to look for any ordered
 841  * extents that exist in the range, rather than just the start of the range.
 842  */
 843 struct btrfs_ordered_extent *btrfs_lookup_ordered_range(
 844                 struct btrfs_inode *inode, u64 file_offset, u64 len)
 845 {
 846         struct btrfs_ordered_inode_tree *tree;
 847         struct rb_node *node;
 848         struct btrfs_ordered_extent *entry = NULL;
 849
 850         tree = &inode->ordered_tree;
 851         spin_lock_irq(&tree->lock);
 852         node = tree_search(tree, file_offset);
 853         if (!node) {
 854                 node = tree_search(tree, file_offset + len);
 855                 if (!node)
 856                         goto out;
 857         }
 858
 859         while (1) {
 860                 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 861                 if (range_overlaps(entry, file_offset, len))
 862                         break;
 863
 864                 if (entry->file_offset >= file_offset + len) {
 865                         entry = NULL;
 866                         break;
 867                 }
 868                 entry = NULL;
 869                 node = rb_next(node);
 870                 if (!node)
 871                         break;
 872         }
 873 out:
 874         if (entry)
 875                 refcount_inc(&entry->refs);
 876         spin_unlock_irq(&tree->lock);
 877         return entry;
 878 }
 879
 880 /*
 881  * Adds all ordered extents to the given list. The list ends up sorted by the
 882  * file_offset of the ordered extents.
 883  */
 884 void btrfs_get_ordered_extents_for_logging(struct btrfs_inode *inode,
 885                                            struct list_head *list)
 886 {
 887         struct btrfs_ordered_inode_tree *tree = &inode->ordered_tree;
 888         struct rb_node *n;
 889
 890         ASSERT(inode_is_locked(&inode->vfs_inode));
 891
 892         spin_lock_irq(&tree->lock);
 893         for (n = rb_first(&tree->tree); n; n = rb_next(n)) {
 894                 struct btrfs_ordered_extent *ordered;
 895
 896                 ordered = rb_entry(n, struct btrfs_ordered_extent, rb_node);
 897
 898                 if (test_bit(BTRFS_ORDERED_LOGGED, &ordered->flags))
 899                         continue;
 900
 901                 ASSERT(list_empty(&ordered->log_list));
 902                 list_add_tail(&ordered->log_list, list);
 903                 refcount_inc(&ordered->refs);
 904         }
 905         spin_unlock_irq(&tree->lock);
 906 }
 907
 908 /*
 909  * lookup and return any extent before 'file_offset'.  NULL is returned
 910  * if none is found
 911  */
 912 struct btrfs_ordered_extent *
 913 btrfs_lookup_first_ordered_extent(struct btrfs_inode *inode, u64 file_offset)
 914 {
 915         struct btrfs_ordered_inode_tree *tree;
 916         struct rb_node *node;
 917         struct btrfs_ordered_extent *entry = NULL;
 918
 919         tree = &inode->ordered_tree;
 920         spin_lock_irq(&tree->lock);
 921         node = tree_search(tree, file_offset);
 922         if (!node)
 923                 goto out;
 924
 925         entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 926         refcount_inc(&entry->refs);
 927 out:
 928         spin_unlock_irq(&tree->lock);
 929         return entry;
 930 }
 931
 932 /*
 933  * Lookup the first ordered extent that overlaps the range
 934  * [@file_offset, @file_offset + @len).
 935  *
 936  * The difference between this and btrfs_lookup_first_ordered_extent() is
 937  * that this one won't return any ordered extent that does not overlap the range.
 938  * And the difference against btrfs_lookup_ordered_extent() is, this function
 939  * ensures the first ordered extent gets returned.
 940  */
 941 struct btrfs_ordered_extent *btrfs_lookup_first_ordered_range(
 942                         struct btrfs_inode *inode, u64 file_offset, u64 len)
 943 {
 944         struct btrfs_ordered_inode_tree *tree = &inode->ordered_tree;
 945         struct rb_node *node;
 946         struct rb_node *cur;
 947         struct rb_node *prev;
 948         struct rb_node *next;
 949         struct btrfs_ordered_extent *entry = NULL;
 950
 951         spin_lock_irq(&tree->lock);
 952         node = tree->tree.rb_node;
 953         /*
 954          * Here we don't want to use tree_search() which will use tree->last
 955          * and screw up the search order.
 956          * And __tree_search() can't return the adjacent ordered extents
 957          * either, thus here we do our own search.
 958          */
 959         while (node) {
 960                 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 961
 962                 if (file_offset < entry->file_offset) {
 963                         node = node->rb_left;
 964                 } else if (file_offset >= entry_end(entry)) {
 965                         node = node->rb_right;
 966                 } else {
 967                         /*
 968                          * Direct hit, got an ordered extent that starts at
 969                          * @file_offset
 970                          */
 971                         goto out;
 972                 }
 973         }
 974         if (!entry) {
 975                 /* Empty tree */
 976                 goto out;
 977         }
 978
 979         cur = &entry->rb_node;
 980         /* We got an entry around @file_offset, check adjacent entries */
 981         if (entry->file_offset < file_offset) {
 982                 prev = cur;
 983                 next = rb_next(cur);
 984         } else {
 985                 prev = rb_prev(cur);
 986                 next = cur;
 987         }
 988         if (prev) {
 989                 entry = rb_entry(prev, struct btrfs_ordered_extent, rb_node);
 990                 if (range_overlaps(entry, file_offset, len))
 991                         goto out;
 992         }
 993         if (next) {
 994                 entry = rb_entry(next, struct btrfs_ordered_extent, rb_node);
 995                 if (range_overlaps(entry, file_offset, len))
 996                         goto out;
 997         }
 998         /* No ordered extent in the range */
 999         entry = NULL;
1000 out:
1001         if (entry)
1002                 refcount_inc(&entry->refs);
1003         spin_unlock_irq(&tree->lock);
1004         return entry;
1005 }
1006
1007 /*
1008  * btrfs_flush_ordered_range - Lock the passed range and ensures all pending
1009  * ordered extents in it are run to completion.
1010  *
1011  * @inode:        Inode whose ordered tree is to be searched
1012  * @start:        Beginning of range to flush
1013  * @end:          Last byte of range to lock
1014  * @cached_state: If passed, will return the extent state responsible for the
1015  * locked range. It's the caller's responsibility to free the cached state.
1016  *
1017  * This function always returns with the given range locked, ensuring after it's
1018  * called no order extent can be pending.
1019  */
1020 void btrfs_lock_and_flush_ordered_range(struct btrfs_inode *inode, u64 start,
1021                                         u64 end,
1022                                         struct extent_state **cached_state)
1023 {
1024         struct btrfs_ordered_extent *ordered;
1025         struct extent_state *cache = NULL;
1026         struct extent_state **cachedp = &cache;
1027
1028         if (cached_state)
1029                 cachedp = cached_state;
1030
1031         while (1) {
1032                 lock_extent_bits(&inode->io_tree, start, end, cachedp);
1033                 ordered = btrfs_lookup_ordered_range(inode, start,
1034                                                      end - start + 1);
1035                 if (!ordered) {
1036                         /*
1037                          * If no external cached_state has been passed then
1038                          * decrement the extra ref taken for cachedp since we
1039                          * aren't exposing it outside of this function
1040                          */
1041                         if (!cached_state)
1042                                 refcount_dec(&cache->refs);
1043                         break;
1044                 }
1045                 unlock_extent_cached(&inode->io_tree, start, end, cachedp);
1046                 btrfs_start_ordered_extent(ordered, 1);
1047                 btrfs_put_ordered_extent(ordered);
1048         }
1049 }
1050
1051 static int clone_ordered_extent(struct btrfs_ordered_extent *ordered, u64 pos,
1052                                 u64 len)
1053 {
1054         struct inode *inode = ordered->inode;
1055         u64 file_offset = ordered->file_offset + pos;
1056         u64 disk_bytenr = ordered->disk_bytenr + pos;
1057         u64 num_bytes = len;
1058         u64 disk_num_bytes = len;
1059         int type;
1060         unsigned long flags_masked = ordered->flags & ~(1 << BTRFS_ORDERED_DIRECT);
1061         int compress_type = ordered->compress_type;
1062         unsigned long weight;
1063         int ret;
1064
1065         weight = hweight_long(flags_masked);
1066         WARN_ON_ONCE(weight > 1);
1067         if (!weight)
1068                 type = 0;
1069         else
1070                 type = __ffs(flags_masked);
1071
1072         if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered->flags)) {
1073                 WARN_ON_ONCE(1);
1074                 ret = btrfs_add_ordered_extent_compress(BTRFS_I(inode),
1075                                 file_offset, disk_bytenr, num_bytes,
1076                                 disk_num_bytes, compress_type);
1077         } else if (test_bit(BTRFS_ORDERED_DIRECT, &ordered->flags)) {
1078                 ret = btrfs_add_ordered_extent_dio(BTRFS_I(inode), file_offset,
1079                                 disk_bytenr, num_bytes, disk_num_bytes, type);
1080         } else {
1081                 ret = btrfs_add_ordered_extent(BTRFS_I(inode), file_offset,
1082                                 disk_bytenr, num_bytes, disk_num_bytes, type);
1083         }
1084
1085         return ret;
1086 }
1087
1088 int btrfs_split_ordered_extent(struct btrfs_ordered_extent *ordered, u64 pre,
1089                                 u64 post)
1090 {
1091         struct inode *inode = ordered->inode;
1092         struct btrfs_ordered_inode_tree *tree = &BTRFS_I(inode)->ordered_tree;
1093         struct rb_node *node;
1094         struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1095         int ret = 0;
1096
1097         spin_lock_irq(&tree->lock);
1098         /* Remove from tree once */
1099         node = &ordered->rb_node;
1100         rb_erase(node, &tree->tree);
1101         RB_CLEAR_NODE(node);
1102         if (tree->last == node)
1103                 tree->last = NULL;
1104
1105         ordered->file_offset += pre;
1106         ordered->disk_bytenr += pre;
1107         ordered->num_bytes -= (pre + post);
1108         ordered->disk_num_bytes -= (pre + post);
1109         ordered->bytes_left -= (pre + post);
1110
1111         /* Re-insert the node */
1112         node = tree_insert(&tree->tree, ordered->file_offset, &ordered->rb_node);
1113         if (node)
1114                 btrfs_panic(fs_info, -EEXIST,
1115                         "zoned: inconsistency in ordered tree at offset %llu",
1116                             ordered->file_offset);
1117
1118         spin_unlock_irq(&tree->lock);
1119
1120         if (pre)
1121                 ret = clone_ordered_extent(ordered, 0, pre);
1122         if (ret == 0 && post)
1123                 ret = clone_ordered_extent(ordered, pre + ordered->disk_num_bytes,
1124                                            post);
1125
1126         return ret;
1127 }
1128
1129 int __init ordered_data_init(void)
1130 {
1131         btrfs_ordered_extent_cache = kmem_cache_create("btrfs_ordered_extent",
1132                                      sizeof(struct btrfs_ordered_extent), 0,
1133                                      SLAB_MEM_SPREAD,
1134                                      NULL);
1135         if (!btrfs_ordered_extent_cache)
1136                 return -ENOMEM;
1137
1138         return 0;
1139 }
1140
1141 void __cold ordered_data_exit(void)
1142 {
1143         kmem_cache_destroy(btrfs_ordered_extent_cache);
1144 }