Line data Source code
1 : #include <linux/bitops.h>
2 : #include <linux/slab.h>
3 : #include <linux/bio.h>
4 : #include <linux/mm.h>
5 : #include <linux/pagemap.h>
6 : #include <linux/page-flags.h>
7 : #include <linux/spinlock.h>
8 : #include <linux/blkdev.h>
9 : #include <linux/swap.h>
10 : #include <linux/writeback.h>
11 : #include <linux/pagevec.h>
12 : #include <linux/prefetch.h>
13 : #include <linux/cleancache.h>
14 : #include "extent_io.h"
15 : #include "extent_map.h"
16 : #include "ctree.h"
17 : #include "btrfs_inode.h"
18 : #include "volumes.h"
19 : #include "check-integrity.h"
20 : #include "locking.h"
21 : #include "rcu-string.h"
22 : #include "backref.h"
23 :
24 : static struct kmem_cache *extent_state_cache;
25 : static struct kmem_cache *extent_buffer_cache;
26 : static struct bio_set *btrfs_bioset;
27 :
28 : #ifdef CONFIG_BTRFS_DEBUG
29 : static LIST_HEAD(buffers);
30 : static LIST_HEAD(states);
31 :
32 : static DEFINE_SPINLOCK(leak_lock);
33 :
34 : static inline
35 : void btrfs_leak_debug_add(struct list_head *new, struct list_head *head)
36 : {
37 : unsigned long flags;
38 :
39 : spin_lock_irqsave(&leak_lock, flags);
40 : list_add(new, head);
41 : spin_unlock_irqrestore(&leak_lock, flags);
42 : }
43 :
44 : static inline
45 : void btrfs_leak_debug_del(struct list_head *entry)
46 : {
47 : unsigned long flags;
48 :
49 : spin_lock_irqsave(&leak_lock, flags);
50 : list_del(entry);
51 : spin_unlock_irqrestore(&leak_lock, flags);
52 : }
53 :
54 : static inline
55 : void btrfs_leak_debug_check(void)
56 : {
57 : struct extent_state *state;
58 : struct extent_buffer *eb;
59 :
60 : while (!list_empty(&states)) {
61 : state = list_entry(states.next, struct extent_state, leak_list);
62 : printk(KERN_ERR "BTRFS: state leak: start %llu end %llu "
63 : "state %lu in tree %p refs %d\n",
64 : state->start, state->end, state->state, state->tree,
65 : atomic_read(&state->refs));
66 : list_del(&state->leak_list);
67 : kmem_cache_free(extent_state_cache, state);
68 : }
69 :
70 : while (!list_empty(&buffers)) {
71 : eb = list_entry(buffers.next, struct extent_buffer, leak_list);
72 : printk(KERN_ERR "BTRFS: buffer leak start %llu len %lu "
73 : "refs %d\n",
74 : eb->start, eb->len, atomic_read(&eb->refs));
75 : list_del(&eb->leak_list);
76 : kmem_cache_free(extent_buffer_cache, eb);
77 : }
78 : }
79 :
80 : #define btrfs_debug_check_extent_io_range(tree, start, end) \
81 : __btrfs_debug_check_extent_io_range(__func__, (tree), (start), (end))
82 : static inline void __btrfs_debug_check_extent_io_range(const char *caller,
83 : struct extent_io_tree *tree, u64 start, u64 end)
84 : {
85 : struct inode *inode;
86 : u64 isize;
87 :
88 : if (!tree->mapping)
89 : return;
90 :
91 : inode = tree->mapping->host;
92 : isize = i_size_read(inode);
93 : if (end >= PAGE_SIZE && (end % 2) == 0 && end != isize - 1) {
94 : printk_ratelimited(KERN_DEBUG
95 : "BTRFS: %s: ino %llu isize %llu odd range [%llu,%llu]\n",
96 : caller, btrfs_ino(inode), isize, start, end);
97 : }
98 : }
99 : #else
100 : #define btrfs_leak_debug_add(new, head) do {} while (0)
101 : #define btrfs_leak_debug_del(entry) do {} while (0)
102 : #define btrfs_leak_debug_check() do {} while (0)
103 : #define btrfs_debug_check_extent_io_range(c, s, e) do {} while (0)
104 : #endif
105 :
106 : #define BUFFER_LRU_MAX 64
107 :
108 : struct tree_entry {
109 : u64 start;
110 : u64 end;
111 : struct rb_node rb_node;
112 : };
113 :
114 : struct extent_page_data {
115 : struct bio *bio;
116 : struct extent_io_tree *tree;
117 : get_extent_t *get_extent;
118 : unsigned long bio_flags;
119 :
120 : /* tells writepage not to lock the state bits for this range
121 : * it still does the unlocking
122 : */
123 : unsigned int extent_locked:1;
124 :
125 : /* tells the submit_bio code to use a WRITE_SYNC */
126 : unsigned int sync_io:1;
127 : };
128 :
129 : static noinline void flush_write_bio(void *data);
130 : static inline struct btrfs_fs_info *
131 : tree_fs_info(struct extent_io_tree *tree)
132 : {
133 0 : if (!tree->mapping)
134 : return NULL;
135 0 : return btrfs_sb(tree->mapping->host->i_sb);
136 : }
137 :
138 0 : int __init extent_io_init(void)
139 : {
140 0 : extent_state_cache = kmem_cache_create("btrfs_extent_state",
141 : sizeof(struct extent_state), 0,
142 : SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
143 0 : if (!extent_state_cache)
144 : return -ENOMEM;
145 :
146 0 : extent_buffer_cache = kmem_cache_create("btrfs_extent_buffer",
147 : sizeof(struct extent_buffer), 0,
148 : SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
149 0 : if (!extent_buffer_cache)
150 : goto free_state_cache;
151 :
152 0 : btrfs_bioset = bioset_create(BIO_POOL_SIZE,
153 : offsetof(struct btrfs_io_bio, bio));
154 0 : if (!btrfs_bioset)
155 : goto free_buffer_cache;
156 :
157 0 : if (bioset_integrity_create(btrfs_bioset, BIO_POOL_SIZE))
158 : goto free_bioset;
159 :
160 : return 0;
161 :
162 : free_bioset:
163 0 : bioset_free(btrfs_bioset);
164 0 : btrfs_bioset = NULL;
165 :
166 : free_buffer_cache:
167 0 : kmem_cache_destroy(extent_buffer_cache);
168 0 : extent_buffer_cache = NULL;
169 :
170 : free_state_cache:
171 0 : kmem_cache_destroy(extent_state_cache);
172 0 : extent_state_cache = NULL;
173 0 : return -ENOMEM;
174 : }
175 :
176 0 : void extent_io_exit(void)
177 : {
178 : btrfs_leak_debug_check();
179 :
180 : /*
181 : * Make sure all delayed rcu free are flushed before we
182 : * destroy caches.
183 : */
184 0 : rcu_barrier();
185 0 : if (extent_state_cache)
186 0 : kmem_cache_destroy(extent_state_cache);
187 0 : if (extent_buffer_cache)
188 0 : kmem_cache_destroy(extent_buffer_cache);
189 0 : if (btrfs_bioset)
190 0 : bioset_free(btrfs_bioset);
191 0 : }
192 :
193 57474 : void extent_io_tree_init(struct extent_io_tree *tree,
194 : struct address_space *mapping)
195 : {
196 57474 : tree->state = RB_ROOT;
197 57474 : tree->ops = NULL;
198 57474 : tree->dirty_bytes = 0;
199 57474 : spin_lock_init(&tree->lock);
200 57474 : tree->mapping = mapping;
201 57474 : }
202 :
203 2270839 : static struct extent_state *alloc_extent_state(gfp_t mask)
204 : {
205 : struct extent_state *state;
206 :
207 2270839 : state = kmem_cache_alloc(extent_state_cache, mask);
208 2271016 : if (!state)
209 : return state;
210 2271022 : state->state = 0;
211 2271022 : state->private = 0;
212 2271022 : state->tree = NULL;
213 : btrfs_leak_debug_add(&state->leak_list, &states);
214 : atomic_set(&state->refs, 1);
215 2271022 : init_waitqueue_head(&state->wq);
216 2270878 : trace_alloc_extent_state(state, mask, _RET_IP_);
217 2270871 : return state;
218 : }
219 :
220 4910880 : void free_extent_state(struct extent_state *state)
221 : {
222 4910880 : if (!state)
223 4911119 : return;
224 4636122 : if (atomic_dec_and_test(&state->refs)) {
225 2271446 : WARN_ON(state->tree);
226 : btrfs_leak_debug_del(&state->leak_list);
227 2271446 : trace_free_extent_state(state, _RET_IP_);
228 2271397 : kmem_cache_free(extent_state_cache, state);
229 : }
230 : }
231 :
232 962717 : static struct rb_node *tree_insert(struct rb_root *root,
233 : struct rb_node *search_start,
234 : u64 offset,
235 : struct rb_node *node,
236 : struct rb_node ***p_in,
237 : struct rb_node **parent_in)
238 : {
239 : struct rb_node **p;
240 : struct rb_node *parent = NULL;
241 : struct tree_entry *entry;
242 :
243 962717 : if (p_in && parent_in) {
244 307644 : p = *p_in;
245 307644 : parent = *parent_in;
246 307644 : goto do_insert;
247 : }
248 :
249 655073 : p = search_start ? &search_start : &root->rb_node;
250 2261712 : while (*p) {
251 : parent = *p;
252 : entry = rb_entry(parent, struct tree_entry, rb_node);
253 :
254 951558 : if (offset < entry->start)
255 733186 : p = &(*p)->rb_left;
256 218372 : else if (offset > entry->end)
257 218380 : p = &(*p)->rb_right;
258 : else
259 : return parent;
260 : }
261 :
262 : do_insert:
263 : rb_link_node(node, parent, p);
264 962725 : rb_insert_color(node, root);
265 962672 : return NULL;
266 : }
267 :
268 3149917 : static struct rb_node *__etree_search(struct extent_io_tree *tree, u64 offset,
269 : struct rb_node **prev_ret,
270 : struct rb_node **next_ret,
271 : struct rb_node ***p_ret,
272 : struct rb_node **parent_ret)
273 : {
274 : struct rb_root *root = &tree->state;
275 3149917 : struct rb_node **n = &root->rb_node;
276 : struct rb_node *prev = NULL;
277 : struct rb_node *orig_prev = NULL;
278 : struct tree_entry *entry;
279 : struct tree_entry *prev_entry = NULL;
280 :
281 10307844 : while (*n) {
282 : prev = *n;
283 6293786 : entry = rb_entry(prev, struct tree_entry, rb_node);
284 : prev_entry = entry;
285 :
286 6293786 : if (offset < entry->start)
287 1644278 : n = &(*n)->rb_left;
288 4649508 : else if (offset > entry->end)
289 2363732 : n = &(*n)->rb_right;
290 : else
291 : return *n;
292 : }
293 :
294 864141 : if (p_ret)
295 364813 : *p_ret = n;
296 864141 : if (parent_ret)
297 364813 : *parent_ret = prev;
298 :
299 864141 : if (prev_ret) {
300 : orig_prev = prev;
301 1157135 : while (prev && offset > prev_entry->end) {
302 292995 : prev = rb_next(prev);
303 292996 : prev_entry = rb_entry(prev, struct tree_entry, rb_node);
304 : }
305 864140 : *prev_ret = prev;
306 : prev = orig_prev;
307 : }
308 :
309 864142 : if (next_ret) {
310 0 : prev_entry = rb_entry(prev, struct tree_entry, rb_node);
311 0 : while (prev && offset < prev_entry->start) {
312 0 : prev = rb_prev(prev);
313 0 : prev_entry = rb_entry(prev, struct tree_entry, rb_node);
314 : }
315 0 : *next_ret = prev;
316 : }
317 : return NULL;
318 : }
319 :
320 : static inline struct rb_node *
321 3150213 : tree_search_for_insert(struct extent_io_tree *tree,
322 : u64 offset,
323 : struct rb_node ***p_ret,
324 : struct rb_node **parent_ret)
325 : {
326 3150213 : struct rb_node *prev = NULL;
327 : struct rb_node *ret;
328 :
329 3150213 : ret = __etree_search(tree, offset, &prev, NULL, p_ret, parent_ret);
330 3150178 : if (!ret)
331 864138 : return prev;
332 : return ret;
333 : }
334 :
335 : static inline struct rb_node *tree_search(struct extent_io_tree *tree,
336 : u64 offset)
337 : {
338 1989273 : return tree_search_for_insert(tree, offset, NULL, NULL);
339 : }
340 :
341 : static void merge_cb(struct extent_io_tree *tree, struct extent_state *new,
342 : struct extent_state *other)
343 : {
344 632459 : if (tree->ops && tree->ops->merge_extent_hook)
345 555607 : tree->ops->merge_extent_hook(tree->mapping->host, new,
346 : other);
347 : }
348 :
349 : /*
350 : * utility function to look for merge candidates inside a given range.
351 : * Any extents with matching state are merged together into a single
352 : * extent in the tree. Extents with EXTENT_IO in their state field
353 : * are not merged because the end_io handlers need to be able to do
354 : * operations on them without sleeping (or doing allocations/splits).
355 : *
356 : * This should be called with the tree lock held.
357 : */
358 2466574 : static void merge_state(struct extent_io_tree *tree,
359 : struct extent_state *state)
360 : {
361 : struct extent_state *other;
362 : struct rb_node *other_node;
363 :
364 1834115 : if (state->state & (EXTENT_IOBITS | EXTENT_BOUNDARY))
365 1834118 : return;
366 :
367 794656 : other_node = rb_prev(&state->rb_node);
368 794660 : if (other_node) {
369 713642 : other = rb_entry(other_node, struct extent_state, rb_node);
370 1349509 : if (other->end == state->start - 1 &&
371 635867 : other->state == state->state) {
372 : merge_cb(tree, state, other);
373 606314 : state->start = other->start;
374 606314 : other->tree = NULL;
375 606314 : rb_erase(&other->rb_node, &tree->state);
376 606313 : free_extent_state(other);
377 : }
378 : }
379 794662 : other_node = rb_next(&state->rb_node);
380 794660 : if (other_node) {
381 492668 : other = rb_entry(other_node, struct extent_state, rb_node);
382 921487 : if (other->start == state->end + 1 &&
383 428819 : other->state == state->state) {
384 : merge_cb(tree, state, other);
385 26145 : state->end = other->end;
386 26145 : other->tree = NULL;
387 26145 : rb_erase(&other->rb_node, &tree->state);
388 26145 : free_extent_state(other);
389 : }
390 : }
391 : }
392 :
393 : static void set_state_cb(struct extent_io_tree *tree,
394 : struct extent_state *state, unsigned long *bits)
395 : {
396 1242906 : if (tree->ops && tree->ops->set_bit_hook)
397 1083211 : tree->ops->set_bit_hook(tree->mapping->host, state, bits);
398 : }
399 :
400 : static void clear_state_cb(struct extent_io_tree *tree,
401 : struct extent_state *state, unsigned long *bits)
402 : {
403 941819 : if (tree->ops && tree->ops->clear_bit_hook)
404 858665 : tree->ops->clear_bit_hook(tree->mapping->host, state, bits);
405 : }
406 :
407 : static void set_state_bits(struct extent_io_tree *tree,
408 : struct extent_state *state, unsigned long *bits);
409 :
410 : /*
411 : * insert an extent_state struct into the tree. 'bits' are set on the
412 : * struct before it is inserted.
413 : *
414 : * This may return -EEXIST if the extent is already there, in which case the
415 : * state struct is freed.
416 : *
417 : * The tree lock is not taken internally. This is a utility function and
418 : * probably isn't what you want to call (see set/clear_extent_bit).
419 : */
420 364809 : static int insert_state(struct extent_io_tree *tree,
421 : struct extent_state *state, u64 start, u64 end,
422 : struct rb_node ***p,
423 : struct rb_node **parent,
424 : unsigned long *bits)
425 : {
426 : struct rb_node *node;
427 :
428 364809 : if (end < start)
429 0 : WARN(1, KERN_ERR "BTRFS: end < start %llu %llu\n",
430 : end, start);
431 364809 : state->start = start;
432 364809 : state->end = end;
433 :
434 364809 : set_state_bits(tree, state, bits);
435 :
436 364803 : node = tree_insert(&tree->state, NULL, end, &state->rb_node, p, parent);
437 364785 : if (node) {
438 : struct extent_state *found;
439 : found = rb_entry(node, struct extent_state, rb_node);
440 0 : printk(KERN_ERR "BTRFS: found node %llu %llu on insert of "
441 : "%llu %llu\n",
442 : found->start, found->end, start, end);
443 0 : return -EEXIST;
444 : }
445 364785 : state->tree = tree;
446 364785 : merge_state(tree, state);
447 364796 : return 0;
448 : }
449 :
450 : static void split_cb(struct extent_io_tree *tree, struct extent_state *orig,
451 : u64 split)
452 : {
453 597916 : if (tree->ops && tree->ops->split_extent_hook)
454 597393 : tree->ops->split_extent_hook(tree->mapping->host, orig, split);
455 : }
456 :
457 : /*
458 : * split a given extent state struct in two, inserting the preallocated
459 : * struct 'prealloc' as the newly created second half. 'split' indicates an
460 : * offset inside 'orig' where it should be split.
461 : *
462 : * Before calling,
463 : * the tree has 'orig' at [orig->start, orig->end]. After calling, there
464 : * are two extent state structs in the tree:
465 : * prealloc: [orig->start, split - 1]
466 : * orig: [ split, orig->end ]
467 : *
468 : * The tree locks are not taken by this function. They need to be held
469 : * by the caller.
470 : */
471 597916 : static int split_state(struct extent_io_tree *tree, struct extent_state *orig,
472 : struct extent_state *prealloc, u64 split)
473 : {
474 : struct rb_node *node;
475 :
476 : split_cb(tree, orig, split);
477 :
478 597918 : prealloc->start = orig->start;
479 597918 : prealloc->end = split - 1;
480 597918 : prealloc->state = orig->state;
481 597918 : orig->start = split;
482 :
483 597918 : node = tree_insert(&tree->state, &orig->rb_node, prealloc->end,
484 : &prealloc->rb_node, NULL, NULL);
485 597913 : if (node) {
486 0 : free_extent_state(prealloc);
487 0 : return -EEXIST;
488 : }
489 597913 : prealloc->tree = tree;
490 597913 : return 0;
491 : }
492 :
493 : static struct extent_state *next_state(struct extent_state *state)
494 : {
495 1273983 : struct rb_node *next = rb_next(&state->rb_node);
496 1273983 : if (next)
497 798086 : return rb_entry(next, struct extent_state, rb_node);
498 : else
499 : return NULL;
500 : }
501 :
502 : /*
503 : * utility function to clear some bits in an extent state struct.
504 : * it will optionally wake up any one waiting on this state (wake == 1).
505 : *
506 : * If no bits are set on the state struct after clearing things, the
507 : * struct is freed and removed from the tree
508 : */
509 1883638 : static struct extent_state *clear_state_bit(struct extent_io_tree *tree,
510 : struct extent_state *state,
511 : unsigned long *bits, int wake)
512 : {
513 : struct extent_state *next;
514 941819 : unsigned long bits_to_clear = *bits & ~EXTENT_CTLBITS;
515 :
516 941819 : if ((bits_to_clear & EXTENT_DIRTY) && (state->state & EXTENT_DIRTY)) {
517 51157 : u64 range = state->end - state->start + 1;
518 51157 : WARN_ON(range > tree->dirty_bytes);
519 51157 : tree->dirty_bytes -= range;
520 : }
521 : clear_state_cb(tree, state, bits);
522 941830 : state->state &= ~bits_to_clear;
523 941830 : if (wake)
524 834402 : wake_up(&state->wq);
525 941844 : if (state->state == 0) {
526 : next = next_state(state);
527 330457 : if (state->tree) {
528 330457 : rb_erase(&state->rb_node, &tree->state);
529 330456 : state->tree = NULL;
530 330456 : free_extent_state(state);
531 : } else {
532 0 : WARN_ON(1);
533 : }
534 : } else {
535 611379 : merge_state(tree, state);
536 : next = next_state(state);
537 : }
538 941835 : return next;
539 : }
540 :
541 : static struct extent_state *
542 : alloc_extent_state_atomic(struct extent_state *prealloc)
543 : {
544 962737 : if (!prealloc)
545 2241 : prealloc = alloc_extent_state(GFP_ATOMIC);
546 :
547 : return prealloc;
548 : }
549 :
550 0 : static void extent_io_tree_panic(struct extent_io_tree *tree, int err)
551 : {
552 0 : btrfs_panic(tree_fs_info(tree), err, "Locking error: "
553 : "Extent tree was modified by another "
554 : "thread while locked.");
555 : }
556 :
557 : /*
558 : * clear some bits on a range in the tree. This may require splitting
559 : * or inserting elements in the tree, so the gfp mask is used to
560 : * indicate which allocations or sleeping are allowed.
561 : *
562 : * pass 'wake' == 1 to kick any sleepers, and 'delete' == 1 to remove
563 : * the given range from the tree regardless of state (ie for truncate).
564 : *
565 : * the range [start, end] is inclusive.
566 : *
567 : * This takes the tree lock, and returns 0 on success and < 0 on error.
568 : */
569 1100499 : int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
570 : unsigned long bits, int wake, int delete,
571 : struct extent_state **cached_state,
572 : gfp_t mask)
573 : {
574 : struct extent_state *state;
575 : struct extent_state *cached;
576 : struct extent_state *prealloc = NULL;
577 : struct rb_node *node;
578 : u64 last_end;
579 : int err;
580 : int clear = 0;
581 :
582 : btrfs_debug_check_extent_io_range(tree, start, end);
583 :
584 1100499 : if (bits & EXTENT_DELALLOC)
585 526283 : bits |= EXTENT_NORESERVE;
586 :
587 1100499 : if (delete)
588 204857 : bits |= ~EXTENT_CTLBITS;
589 1100499 : bits |= EXTENT_FIRST_DELALLOC;
590 :
591 1100499 : if (bits & (EXTENT_IOBITS | EXTENT_BOUNDARY))
592 : clear = 1;
593 : again:
594 1101537 : if (!prealloc && (mask & __GFP_WAIT)) {
595 1069637 : prealloc = alloc_extent_state(mask);
596 1069636 : if (!prealloc)
597 : return -ENOMEM;
598 : }
599 :
600 : spin_lock(&tree->lock);
601 1101623 : if (cached_state) {
602 843781 : cached = *cached_state;
603 :
604 843781 : if (clear) {
605 778088 : *cached_state = NULL;
606 : cached_state = NULL;
607 : }
608 :
609 1665334 : if (cached && cached->tree && cached->start <= start &&
610 821553 : cached->end > start) {
611 821538 : if (clear)
612 775898 : atomic_dec(&cached->refs);
613 : state = cached;
614 821533 : goto hit_next;
615 : }
616 22243 : if (clear)
617 2184 : free_extent_state(cached);
618 : }
619 : /*
620 : * this search will find the extents that end after
621 : * our range starts
622 : */
623 : node = tree_search(tree, start);
624 280079 : if (!node)
625 : goto out;
626 272885 : state = rb_entry(node, struct extent_state, rb_node);
627 : hit_next:
628 1130665 : if (state->start > end)
629 : goto out;
630 948435 : WARN_ON(state->end < start);
631 948438 : last_end = state->end;
632 :
633 : /* the state doesn't have the wanted bits, go ahead */
634 948438 : if (!(state->state & bits)) {
635 : state = next_state(state);
636 26645 : goto next;
637 : }
638 :
639 : /*
640 : * | ---- desired range ---- |
641 : * | state | or
642 : * | ------------- state -------------- |
643 : *
644 : * We need to split the extent we found, and may flip
645 : * bits on second half.
646 : *
647 : * If the extent we found extends past our range, we
648 : * just split and search again. It'll get split again
649 : * the next time though.
650 : *
651 : * If the extent we found is inside our range, we clear
652 : * the desired bit on it.
653 : */
654 :
655 921794 : if (state->start < start) {
656 : prealloc = alloc_extent_state_atomic(prealloc);
657 249 : BUG_ON(!prealloc);
658 249 : err = split_state(tree, state, prealloc, start);
659 249 : if (err)
660 0 : extent_io_tree_panic(tree, err);
661 :
662 : prealloc = NULL;
663 249 : if (err)
664 : goto out;
665 249 : if (state->end <= end) {
666 249 : state = clear_state_bit(tree, state, &bits, wake);
667 249 : goto next;
668 : }
669 : goto search_again;
670 : }
671 : /*
672 : * | ---- desired range ---- |
673 : * | state |
674 : * We need to split the extent, and clear the bit
675 : * on the first half
676 : */
677 921545 : if (state->start <= end && state->end > end) {
678 : prealloc = alloc_extent_state_atomic(prealloc);
679 443 : BUG_ON(!prealloc);
680 443 : err = split_state(tree, state, prealloc, end + 1);
681 443 : if (err)
682 0 : extent_io_tree_panic(tree, err);
683 :
684 443 : if (wake)
685 189 : wake_up(&state->wq);
686 :
687 443 : clear_state_bit(tree, prealloc, &bits, wake);
688 :
689 : prealloc = NULL;
690 443 : goto out;
691 : }
692 :
693 921102 : state = clear_state_bit(tree, state, &bits, wake);
694 : next:
695 947982 : if (last_end == (u64)-1)
696 : goto out;
697 947881 : start = last_end + 1;
698 984208 : if (start <= end && state && !need_resched())
699 : goto hit_next;
700 : goto search_again;
701 :
702 : out:
703 : spin_unlock(&tree->lock);
704 1100554 : if (prealloc)
705 1069252 : free_extent_state(prealloc);
706 :
707 : return 0;
708 :
709 : search_again:
710 911634 : if (start > end)
711 : goto out;
712 : spin_unlock(&tree->lock);
713 1038 : if (mask & __GFP_WAIT)
714 978 : cond_resched();
715 : goto again;
716 : }
717 :
718 56 : static void wait_on_state(struct extent_io_tree *tree,
719 : struct extent_state *state)
720 : __releases(tree->lock)
721 : __acquires(tree->lock)
722 : {
723 112 : DEFINE_WAIT(wait);
724 56 : prepare_to_wait(&state->wq, &wait, TASK_UNINTERRUPTIBLE);
725 : spin_unlock(&tree->lock);
726 56 : schedule();
727 : spin_lock(&tree->lock);
728 56 : finish_wait(&state->wq, &wait);
729 56 : }
730 :
731 : /*
732 : * waits for one or more bits to clear on a range in the state tree.
733 : * The range [start, end] is inclusive.
734 : * The tree lock is taken by this function
735 : */
736 44 : static void wait_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
737 : unsigned long bits)
738 : {
739 : struct extent_state *state;
740 : struct rb_node *node;
741 :
742 : btrfs_debug_check_extent_io_range(tree, start, end);
743 :
744 : spin_lock(&tree->lock);
745 : again:
746 : while (1) {
747 : /*
748 : * this search will find all the extents that end after
749 : * our range starts
750 : */
751 : node = tree_search(tree, start);
752 : process_node:
753 132 : if (!node)
754 : break;
755 :
756 115 : state = rb_entry(node, struct extent_state, rb_node);
757 :
758 115 : if (state->start > end)
759 : goto out;
760 :
761 115 : if (state->state & bits) {
762 : start = state->start;
763 56 : atomic_inc(&state->refs);
764 56 : wait_on_state(tree, state);
765 56 : free_extent_state(state);
766 56 : goto again;
767 : }
768 59 : start = state->end + 1;
769 :
770 59 : if (start > end)
771 : break;
772 :
773 32 : if (!cond_resched_lock(&tree->lock)) {
774 32 : node = rb_next(node);
775 32 : goto process_node;
776 : }
777 : }
778 : out:
779 : spin_unlock(&tree->lock);
780 44 : }
781 :
782 2485812 : static void set_state_bits(struct extent_io_tree *tree,
783 : struct extent_state *state,
784 : unsigned long *bits)
785 : {
786 1242906 : unsigned long bits_to_set = *bits & ~EXTENT_CTLBITS;
787 :
788 : set_state_cb(tree, state, bits);
789 1242945 : if ((bits_to_set & EXTENT_DIRTY) && !(state->state & EXTENT_DIRTY)) {
790 126806 : u64 range = state->end - state->start + 1;
791 126806 : tree->dirty_bytes += range;
792 : }
793 1242945 : state->state |= bits_to_set;
794 1242945 : }
795 :
796 1349025 : static void cache_state(struct extent_state *state,
797 : struct extent_state **cached_ptr)
798 : {
799 1349025 : if (cached_ptr && !(*cached_ptr)) {
800 835966 : if (state->state & (EXTENT_IOBITS | EXTENT_BOUNDARY)) {
801 775868 : *cached_ptr = state;
802 775868 : atomic_inc(&state->refs);
803 : }
804 : }
805 1349062 : }
806 :
807 : /*
808 : * set some bits on a range in the tree. This may require allocations or
809 : * sleeping, so the gfp mask is used to indicate what is allowed.
810 : *
811 : * If any of the exclusive bits are set, this will fail with -EEXIST if some
812 : * part of the range already has the desired bits set. The start of the
813 : * existing range is returned in failed_start in this case.
814 : *
815 : * [start, end] is inclusive This takes the tree lock.
816 : */
817 :
818 : static int __must_check
819 1186226 : __set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
820 : unsigned long bits, unsigned long exclusive_bits,
821 : u64 *failed_start, struct extent_state **cached_state,
822 : gfp_t mask)
823 : {
824 : struct extent_state *state;
825 : struct extent_state *prealloc = NULL;
826 : struct rb_node *node;
827 : struct rb_node **p;
828 : struct rb_node *parent;
829 : int err = 0;
830 : u64 last_start;
831 : u64 last_end;
832 :
833 : btrfs_debug_check_extent_io_range(tree, start, end);
834 :
835 1186226 : bits |= EXTENT_FIRST_DELALLOC;
836 : again:
837 1209997 : if (!prealloc && (mask & __GFP_WAIT)) {
838 1179170 : prealloc = alloc_extent_state(mask);
839 1179180 : BUG_ON(!prealloc);
840 : }
841 :
842 : spin_lock(&tree->lock);
843 1210110 : if (cached_state && *cached_state) {
844 : state = *cached_state;
845 140860 : if (state->start <= start && state->end > start &&
846 68966 : state->tree) {
847 : node = &state->rb_node;
848 : goto hit_next;
849 : }
850 : }
851 : /*
852 : * this search will find all the extents that end after
853 : * our range starts.
854 : */
855 1141153 : node = tree_search_for_insert(tree, start, &p, &parent);
856 1141155 : if (!node) {
857 : prealloc = alloc_extent_state_atomic(prealloc);
858 307658 : BUG_ON(!prealloc);
859 307658 : err = insert_state(tree, prealloc, start, end,
860 : &p, &parent, &bits);
861 307644 : if (err)
862 0 : extent_io_tree_panic(tree, err);
863 :
864 307644 : cache_state(prealloc, cached_state);
865 : prealloc = NULL;
866 307650 : goto out;
867 : }
868 833497 : state = rb_entry(node, struct extent_state, rb_node);
869 : hit_next:
870 929642 : last_start = state->start;
871 929642 : last_end = state->end;
872 :
873 : /*
874 : * | ---- desired range ---- |
875 : * | state |
876 : *
877 : * Just lock what we found and keep going
878 : */
879 929642 : if (state->start == start && state->end <= end) {
880 275246 : if (state->state & exclusive_bits) {
881 34 : *failed_start = state->start;
882 : err = -EEXIST;
883 34 : goto out;
884 : }
885 :
886 275212 : set_state_bits(tree, state, &bits);
887 275206 : cache_state(state, cached_state);
888 275201 : merge_state(tree, state);
889 275196 : if (last_end == (u64)-1)
890 : goto out;
891 275193 : start = last_end + 1;
892 : state = next_state(state);
893 290770 : if (start < end && state && state->start == start &&
894 : !need_resched())
895 : goto hit_next;
896 : goto search_again;
897 : }
898 :
899 : /*
900 : * | ---- desired range ---- |
901 : * | state |
902 : * or
903 : * | ------------- state -------------- |
904 : *
905 : * We need to split the extent we found, and may flip bits on
906 : * second half.
907 : *
908 : * If the extent we found extends past our
909 : * range, we just split and search again. It'll get split
910 : * again the next time though.
911 : *
912 : * If the extent we found is inside our range, we set the
913 : * desired bit on it.
914 : */
915 654396 : if (state->start < start) {
916 44587 : if (state->state & exclusive_bits) {
917 2 : *failed_start = start;
918 : err = -EEXIST;
919 2 : goto out;
920 : }
921 :
922 : prealloc = alloc_extent_state_atomic(prealloc);
923 44585 : BUG_ON(!prealloc);
924 44585 : err = split_state(tree, state, prealloc, start);
925 44583 : if (err)
926 0 : extent_io_tree_panic(tree, err);
927 :
928 : prealloc = NULL;
929 44583 : if (err)
930 : goto out;
931 44583 : if (state->end <= end) {
932 30306 : set_state_bits(tree, state, &bits);
933 30306 : cache_state(state, cached_state);
934 30306 : merge_state(tree, state);
935 30306 : if (last_end == (u64)-1)
936 : goto out;
937 30306 : start = last_end + 1;
938 : state = next_state(state);
939 41981 : if (start < end && state && state->start == start &&
940 : !need_resched())
941 : goto hit_next;
942 : }
943 : goto search_again;
944 : }
945 : /*
946 : * | ---- desired range ---- |
947 : * | state | or | state |
948 : *
949 : * There's a hole, we need to insert something in it and
950 : * ignore the extent we found.
951 : */
952 609809 : if (state->start > start) {
953 : u64 this_end;
954 57158 : if (end < last_start)
955 : this_end = end;
956 : else
957 5786 : this_end = last_start - 1;
958 :
959 : prealloc = alloc_extent_state_atomic(prealloc);
960 57158 : BUG_ON(!prealloc);
961 :
962 : /*
963 : * Avoid to free 'prealloc' if it can be merged with
964 : * the later extent.
965 : */
966 57158 : err = insert_state(tree, prealloc, start, this_end,
967 : NULL, NULL, &bits);
968 57160 : if (err)
969 0 : extent_io_tree_panic(tree, err);
970 :
971 57160 : cache_state(prealloc, cached_state);
972 : prealloc = NULL;
973 57160 : start = this_end + 1;
974 57160 : goto search_again;
975 : }
976 : /*
977 : * | ---- desired range ---- |
978 : * | state |
979 : * We need to split the extent, and set the bit
980 : * on the first half
981 : */
982 552651 : if (state->start <= end && state->end > end) {
983 552652 : if (state->state & exclusive_bits) {
984 8 : *failed_start = start;
985 : err = -EEXIST;
986 8 : goto out;
987 : }
988 :
989 : prealloc = alloc_extent_state_atomic(prealloc);
990 552644 : BUG_ON(!prealloc);
991 552644 : err = split_state(tree, state, prealloc, end + 1);
992 552641 : if (err)
993 0 : extent_io_tree_panic(tree, err);
994 :
995 552641 : set_state_bits(tree, prealloc, &bits);
996 552638 : cache_state(prealloc, cached_state);
997 552643 : merge_state(tree, prealloc);
998 : prealloc = NULL;
999 552643 : goto out;
1000 : }
1001 :
1002 : goto search_again;
1003 :
1004 : out:
1005 : spin_unlock(&tree->lock);
1006 1186218 : if (prealloc)
1007 219202 : free_extent_state(prealloc);
1008 :
1009 1186240 : return err;
1010 :
1011 : search_again:
1012 349751 : if (start > end)
1013 : goto out;
1014 : spin_unlock(&tree->lock);
1015 23771 : if (mask & __GFP_WAIT)
1016 23522 : cond_resched();
1017 : goto again;
1018 : }
1019 :
1020 25258 : int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
1021 : unsigned long bits, u64 * failed_start,
1022 : struct extent_state **cached_state, gfp_t mask)
1023 : {
1024 722852 : return __set_extent_bit(tree, start, end, bits, 0, failed_start,
1025 : cached_state, mask);
1026 : }
1027 :
1028 :
1029 : /**
1030 : * convert_extent_bit - convert all bits in a given range from one bit to
1031 : * another
1032 : * @tree: the io tree to search
1033 : * @start: the start offset in bytes
1034 : * @end: the end offset in bytes (inclusive)
1035 : * @bits: the bits to set in this range
1036 : * @clear_bits: the bits to clear in this range
1037 : * @cached_state: state that we're going to cache
1038 : * @mask: the allocation mask
1039 : *
1040 : * This will go through and set bits for the given range. If any states exist
1041 : * already in this range they are set with the given bit and cleared of the
1042 : * clear_bits. This is only meant to be used by things that are mergeable, ie
1043 : * converting from say DELALLOC to DIRTY. This is not meant to be used with
1044 : * boundary bits like LOCK.
1045 : */
1046 20035 : int convert_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
1047 : unsigned long bits, unsigned long clear_bits,
1048 : struct extent_state **cached_state, gfp_t mask)
1049 : {
1050 : struct extent_state *state;
1051 : struct extent_state *prealloc = NULL;
1052 : struct rb_node *node;
1053 : struct rb_node **p;
1054 : struct rb_node *parent;
1055 : int err = 0;
1056 : u64 last_start;
1057 : u64 last_end;
1058 :
1059 : btrfs_debug_check_extent_io_range(tree, start, end);
1060 :
1061 : again:
1062 20035 : if (!prealloc && (mask & __GFP_WAIT)) {
1063 20035 : prealloc = alloc_extent_state(mask);
1064 20035 : if (!prealloc)
1065 : return -ENOMEM;
1066 : }
1067 :
1068 : spin_lock(&tree->lock);
1069 20035 : if (cached_state && *cached_state) {
1070 : state = *cached_state;
1071 0 : if (state->start <= start && state->end > start &&
1072 0 : state->tree) {
1073 : node = &state->rb_node;
1074 : goto hit_next;
1075 : }
1076 : }
1077 :
1078 : /*
1079 : * this search will find all the extents that end after
1080 : * our range starts.
1081 : */
1082 20035 : node = tree_search_for_insert(tree, start, &p, &parent);
1083 20035 : if (!node) {
1084 : prealloc = alloc_extent_state_atomic(prealloc);
1085 0 : if (!prealloc) {
1086 : err = -ENOMEM;
1087 : goto out;
1088 : }
1089 0 : err = insert_state(tree, prealloc, start, end,
1090 : &p, &parent, &bits);
1091 0 : if (err)
1092 0 : extent_io_tree_panic(tree, err);
1093 0 : cache_state(prealloc, cached_state);
1094 : prealloc = NULL;
1095 0 : goto out;
1096 : }
1097 20035 : state = rb_entry(node, struct extent_state, rb_node);
1098 : hit_next:
1099 20035 : last_start = state->start;
1100 20035 : last_end = state->end;
1101 :
1102 : /*
1103 : * | ---- desired range ---- |
1104 : * | state |
1105 : *
1106 : * Just lock what we found and keep going
1107 : */
1108 20035 : if (state->start == start && state->end <= end) {
1109 20035 : set_state_bits(tree, state, &bits);
1110 20035 : cache_state(state, cached_state);
1111 20035 : state = clear_state_bit(tree, state, &clear_bits, 0);
1112 20035 : if (last_end == (u64)-1)
1113 : goto out;
1114 20035 : start = last_end + 1;
1115 20035 : if (start < end && state && state->start == start &&
1116 : !need_resched())
1117 : goto hit_next;
1118 : goto search_again;
1119 : }
1120 :
1121 : /*
1122 : * | ---- desired range ---- |
1123 : * | state |
1124 : * or
1125 : * | ------------- state -------------- |
1126 : *
1127 : * We need to split the extent we found, and may flip bits on
1128 : * second half.
1129 : *
1130 : * If the extent we found extends past our
1131 : * range, we just split and search again. It'll get split
1132 : * again the next time though.
1133 : *
1134 : * If the extent we found is inside our range, we set the
1135 : * desired bit on it.
1136 : */
1137 0 : if (state->start < start) {
1138 : prealloc = alloc_extent_state_atomic(prealloc);
1139 0 : if (!prealloc) {
1140 : err = -ENOMEM;
1141 : goto out;
1142 : }
1143 0 : err = split_state(tree, state, prealloc, start);
1144 0 : if (err)
1145 0 : extent_io_tree_panic(tree, err);
1146 : prealloc = NULL;
1147 0 : if (err)
1148 : goto out;
1149 0 : if (state->end <= end) {
1150 0 : set_state_bits(tree, state, &bits);
1151 0 : cache_state(state, cached_state);
1152 0 : state = clear_state_bit(tree, state, &clear_bits, 0);
1153 0 : if (last_end == (u64)-1)
1154 : goto out;
1155 0 : start = last_end + 1;
1156 0 : if (start < end && state && state->start == start &&
1157 : !need_resched())
1158 : goto hit_next;
1159 : }
1160 : goto search_again;
1161 : }
1162 : /*
1163 : * | ---- desired range ---- |
1164 : * | state | or | state |
1165 : *
1166 : * There's a hole, we need to insert something in it and
1167 : * ignore the extent we found.
1168 : */
1169 0 : if (state->start > start) {
1170 : u64 this_end;
1171 0 : if (end < last_start)
1172 : this_end = end;
1173 : else
1174 0 : this_end = last_start - 1;
1175 :
1176 : prealloc = alloc_extent_state_atomic(prealloc);
1177 0 : if (!prealloc) {
1178 : err = -ENOMEM;
1179 : goto out;
1180 : }
1181 :
1182 : /*
1183 : * Avoid to free 'prealloc' if it can be merged with
1184 : * the later extent.
1185 : */
1186 0 : err = insert_state(tree, prealloc, start, this_end,
1187 : NULL, NULL, &bits);
1188 0 : if (err)
1189 0 : extent_io_tree_panic(tree, err);
1190 0 : cache_state(prealloc, cached_state);
1191 : prealloc = NULL;
1192 0 : start = this_end + 1;
1193 0 : goto search_again;
1194 : }
1195 : /*
1196 : * | ---- desired range ---- |
1197 : * | state |
1198 : * We need to split the extent, and set the bit
1199 : * on the first half
1200 : */
1201 0 : if (state->start <= end && state->end > end) {
1202 : prealloc = alloc_extent_state_atomic(prealloc);
1203 0 : if (!prealloc) {
1204 : err = -ENOMEM;
1205 : goto out;
1206 : }
1207 :
1208 0 : err = split_state(tree, state, prealloc, end + 1);
1209 0 : if (err)
1210 0 : extent_io_tree_panic(tree, err);
1211 :
1212 0 : set_state_bits(tree, prealloc, &bits);
1213 0 : cache_state(prealloc, cached_state);
1214 0 : clear_state_bit(tree, prealloc, &clear_bits, 0);
1215 : prealloc = NULL;
1216 0 : goto out;
1217 : }
1218 :
1219 : goto search_again;
1220 :
1221 : out:
1222 : spin_unlock(&tree->lock);
1223 20035 : if (prealloc)
1224 20035 : free_extent_state(prealloc);
1225 :
1226 20035 : return err;
1227 :
1228 : search_again:
1229 20035 : if (start > end)
1230 : goto out;
1231 : spin_unlock(&tree->lock);
1232 0 : if (mask & __GFP_WAIT)
1233 0 : cond_resched();
1234 : goto again;
1235 : }
1236 :
1237 : /* wrappers around set/clear extent bit */
1238 126731 : int set_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end,
1239 : gfp_t mask)
1240 : {
1241 126737 : return set_extent_bit(tree, start, end, EXTENT_DIRTY, NULL,
1242 : NULL, mask);
1243 : }
1244 :
1245 3159 : int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
1246 : unsigned long bits, gfp_t mask)
1247 : {
1248 3159 : return set_extent_bit(tree, start, end, bits, NULL,
1249 : NULL, mask);
1250 : }
1251 :
1252 3025 : int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
1253 : unsigned long bits, gfp_t mask)
1254 : {
1255 3025 : return clear_extent_bit(tree, start, end, bits, 0, 0, NULL, mask);
1256 : }
1257 :
1258 131791 : int set_extent_delalloc(struct extent_io_tree *tree, u64 start, u64 end,
1259 : struct extent_state **cached_state, gfp_t mask)
1260 : {
1261 131792 : return set_extent_bit(tree, start, end,
1262 : EXTENT_DELALLOC | EXTENT_UPTODATE,
1263 : NULL, cached_state, mask);
1264 : }
1265 :
1266 1337 : int set_extent_defrag(struct extent_io_tree *tree, u64 start, u64 end,
1267 : struct extent_state **cached_state, gfp_t mask)
1268 : {
1269 1337 : return set_extent_bit(tree, start, end,
1270 : EXTENT_DELALLOC | EXTENT_UPTODATE | EXTENT_DEFRAG,
1271 : NULL, cached_state, mask);
1272 : }
1273 :
1274 32303 : int clear_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end,
1275 : gfp_t mask)
1276 : {
1277 32303 : return clear_extent_bit(tree, start, end,
1278 : EXTENT_DIRTY | EXTENT_DELALLOC |
1279 : EXTENT_DO_ACCOUNTING, 0, 0, NULL, mask);
1280 : }
1281 :
1282 1384 : int set_extent_new(struct extent_io_tree *tree, u64 start, u64 end,
1283 : gfp_t mask)
1284 : {
1285 1384 : return set_extent_bit(tree, start, end, EXTENT_NEW, NULL,
1286 : NULL, mask);
1287 : }
1288 :
1289 452 : int set_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end,
1290 : struct extent_state **cached_state, gfp_t mask)
1291 : {
1292 452 : return set_extent_bit(tree, start, end, EXTENT_UPTODATE, NULL,
1293 : cached_state, mask);
1294 : }
1295 :
1296 0 : int clear_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end,
1297 : struct extent_state **cached_state, gfp_t mask)
1298 : {
1299 0 : return clear_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, 0,
1300 : cached_state, mask);
1301 : }
1302 :
1303 : /*
1304 : * either insert or lock state struct between start and end use mask to tell
1305 : * us if waiting is desired.
1306 : */
1307 463423 : int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
1308 : unsigned long bits, struct extent_state **cached_state)
1309 : {
1310 : int err;
1311 : u64 failed_start;
1312 : while (1) {
1313 463467 : err = __set_extent_bit(tree, start, end, EXTENT_LOCKED | bits,
1314 : EXTENT_LOCKED, &failed_start,
1315 : cached_state, GFP_NOFS);
1316 463459 : if (err == -EEXIST) {
1317 44 : wait_extent_bit(tree, failed_start, end, EXTENT_LOCKED);
1318 44 : start = failed_start;
1319 : } else
1320 : break;
1321 44 : WARN_ON(start > end);
1322 : }
1323 463415 : return err;
1324 : }
1325 :
1326 2746 : int lock_extent(struct extent_io_tree *tree, u64 start, u64 end)
1327 : {
1328 90403 : return lock_extent_bits(tree, start, end, 0, NULL);
1329 : }
1330 :
1331 3 : int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end)
1332 : {
1333 : int err;
1334 : u64 failed_start;
1335 :
1336 3 : err = __set_extent_bit(tree, start, end, EXTENT_LOCKED, EXTENT_LOCKED,
1337 : &failed_start, NULL, GFP_NOFS);
1338 3 : if (err == -EEXIST) {
1339 0 : if (failed_start > start)
1340 0 : clear_extent_bit(tree, start, failed_start - 1,
1341 : EXTENT_LOCKED, 1, 0, NULL, GFP_NOFS);
1342 : return 0;
1343 : }
1344 : return 1;
1345 : }
1346 :
1347 112703 : int unlock_extent_cached(struct extent_io_tree *tree, u64 start, u64 end,
1348 : struct extent_state **cached, gfp_t mask)
1349 : {
1350 547972 : return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, cached,
1351 : mask);
1352 : }
1353 :
1354 2967 : int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end)
1355 : {
1356 2967 : return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, NULL,
1357 : GFP_NOFS);
1358 : }
1359 :
1360 155 : int extent_range_clear_dirty_for_io(struct inode *inode, u64 start, u64 end)
1361 : {
1362 155 : unsigned long index = start >> PAGE_CACHE_SHIFT;
1363 155 : unsigned long end_index = end >> PAGE_CACHE_SHIFT;
1364 : struct page *page;
1365 :
1366 4572 : while (index <= end_index) {
1367 4262 : page = find_get_page(inode->i_mapping, index);
1368 4232 : BUG_ON(!page); /* Pages should be in the extent_io_tree */
1369 4232 : clear_page_dirty_for_io(page);
1370 4250 : page_cache_release(page);
1371 4262 : index++;
1372 : }
1373 155 : return 0;
1374 : }
1375 :
1376 2 : int extent_range_redirty_for_io(struct inode *inode, u64 start, u64 end)
1377 : {
1378 2 : unsigned long index = start >> PAGE_CACHE_SHIFT;
1379 2 : unsigned long end_index = end >> PAGE_CACHE_SHIFT;
1380 : struct page *page;
1381 :
1382 6 : while (index <= end_index) {
1383 2 : page = find_get_page(inode->i_mapping, index);
1384 2 : BUG_ON(!page); /* Pages should be in the extent_io_tree */
1385 2 : account_page_redirty(page);
1386 2 : __set_page_dirty_nobuffers(page);
1387 2 : page_cache_release(page);
1388 2 : index++;
1389 : }
1390 2 : return 0;
1391 : }
1392 :
1393 : /*
1394 : * helper function to set both pages and extents in the tree writeback
1395 : */
1396 1308912 : static int set_range_writeback(struct extent_io_tree *tree, u64 start, u64 end)
1397 : {
1398 1308912 : unsigned long index = start >> PAGE_CACHE_SHIFT;
1399 1308912 : unsigned long end_index = end >> PAGE_CACHE_SHIFT;
1400 : struct page *page;
1401 :
1402 2617824 : while (index <= end_index) {
1403 1308913 : page = find_get_page(tree->mapping, index);
1404 1308914 : BUG_ON(!page); /* Pages should be in the extent_io_tree */
1405 : set_page_writeback(page);
1406 1308882 : page_cache_release(page);
1407 1308912 : index++;
1408 : }
1409 1308911 : return 0;
1410 : }
1411 :
1412 : /* find the first state struct with 'bits' set after 'start', and
1413 : * return it. tree->lock must be held. NULL will returned if
1414 : * nothing was found after 'start'
1415 : */
1416 : static struct extent_state *
1417 123332 : find_first_extent_bit_state(struct extent_io_tree *tree,
1418 : u64 start, unsigned long bits)
1419 : {
1420 : struct rb_node *node;
1421 : struct extent_state *state;
1422 :
1423 : /*
1424 : * this search will find all the extents that end after
1425 : * our range starts.
1426 : */
1427 : node = tree_search(tree, start);
1428 123332 : if (!node)
1429 : goto out;
1430 :
1431 : while (1) {
1432 106257 : state = rb_entry(node, struct extent_state, rb_node);
1433 106257 : if (state->end >= start && (state->state & bits))
1434 : return state;
1435 :
1436 66 : node = rb_next(node);
1437 66 : if (!node)
1438 : break;
1439 : }
1440 : out:
1441 : return NULL;
1442 : }
1443 :
1444 : /*
1445 : * find the first offset in the io tree with 'bits' set. zero is
1446 : * returned if we find something, and *start_ret and *end_ret are
1447 : * set to reflect the state struct that was found.
1448 : *
1449 : * If nothing was found, 1 is returned. If found something, return 0.
1450 : */
1451 123332 : int find_first_extent_bit(struct extent_io_tree *tree, u64 start,
1452 : u64 *start_ret, u64 *end_ret, unsigned long bits,
1453 : struct extent_state **cached_state)
1454 : {
1455 : struct extent_state *state;
1456 : struct rb_node *n;
1457 : int ret = 1;
1458 :
1459 : spin_lock(&tree->lock);
1460 123332 : if (cached_state && *cached_state) {
1461 : state = *cached_state;
1462 0 : if (state->end == start - 1 && state->tree) {
1463 0 : n = rb_next(&state->rb_node);
1464 0 : while (n) {
1465 0 : state = rb_entry(n, struct extent_state,
1466 : rb_node);
1467 0 : if (state->state & bits)
1468 : goto got_it;
1469 0 : n = rb_next(n);
1470 : }
1471 0 : free_extent_state(*cached_state);
1472 0 : *cached_state = NULL;
1473 0 : goto out;
1474 : }
1475 0 : free_extent_state(*cached_state);
1476 0 : *cached_state = NULL;
1477 : }
1478 :
1479 123332 : state = find_first_extent_bit_state(tree, start, bits);
1480 : got_it:
1481 123332 : if (state) {
1482 106191 : cache_state(state, cached_state);
1483 106191 : *start_ret = state->start;
1484 106191 : *end_ret = state->end;
1485 : ret = 0;
1486 : }
1487 : out:
1488 : spin_unlock(&tree->lock);
1489 123332 : return ret;
1490 : }
1491 :
1492 : /*
1493 : * find a contiguous range of bytes in the file marked as delalloc, not
1494 : * more than 'max_bytes'. start and end are used to return the range,
1495 : *
1496 : * 1 is returned if we find something, 0 if nothing was in the tree
1497 : */
1498 1312844 : static noinline u64 find_delalloc_range(struct extent_io_tree *tree,
1499 : u64 *start, u64 *end, u64 max_bytes,
1500 : struct extent_state **cached_state)
1501 : {
1502 : struct rb_node *node;
1503 : struct extent_state *state;
1504 1312844 : u64 cur_start = *start;
1505 : u64 found = 0;
1506 : u64 total_bytes = 0;
1507 :
1508 : spin_lock(&tree->lock);
1509 :
1510 : /*
1511 : * this search will find all the extents that end after
1512 : * our range starts.
1513 : */
1514 : node = tree_search(tree, cur_start);
1515 1312861 : if (!node) {
1516 : if (!found)
1517 0 : *end = (u64)-1;
1518 : goto out;
1519 : }
1520 :
1521 : while (1) {
1522 1324052 : state = rb_entry(node, struct extent_state, rb_node);
1523 1332647 : if (found && (state->start != cur_start ||
1524 8595 : (state->state & EXTENT_BOUNDARY))) {
1525 : goto out;
1526 : }
1527 1320421 : if (!(state->state & EXTENT_DELALLOC)) {
1528 1290539 : if (!found)
1529 1282989 : *end = state->end;
1530 : goto out;
1531 : }
1532 29882 : if (!found) {
1533 29879 : *start = state->start;
1534 29879 : *cached_state = state;
1535 29879 : atomic_inc(&state->refs);
1536 : }
1537 29884 : found++;
1538 29884 : *end = state->end;
1539 29884 : cur_start = state->end + 1;
1540 29884 : node = rb_next(node);
1541 29884 : total_bytes += state->end - state->start + 1;
1542 29884 : if (total_bytes >= max_bytes)
1543 : break;
1544 29882 : if (!node)
1545 : break;
1546 : }
1547 : out:
1548 : spin_unlock(&tree->lock);
1549 1312840 : return found;
1550 : }
1551 :
1552 0 : static noinline void __unlock_for_delalloc(struct inode *inode,
1553 : struct page *locked_page,
1554 : u64 start, u64 end)
1555 : {
1556 : int ret;
1557 : struct page *pages[16];
1558 0 : unsigned long index = start >> PAGE_CACHE_SHIFT;
1559 0 : unsigned long end_index = end >> PAGE_CACHE_SHIFT;
1560 0 : unsigned long nr_pages = end_index - index + 1;
1561 : int i;
1562 :
1563 0 : if (index == locked_page->index && end_index == index)
1564 0 : return;
1565 :
1566 0 : while (nr_pages > 0) {
1567 0 : ret = find_get_pages_contig(inode->i_mapping, index,
1568 0 : min_t(unsigned long, nr_pages,
1569 : ARRAY_SIZE(pages)), pages);
1570 0 : for (i = 0; i < ret; i++) {
1571 0 : if (pages[i] != locked_page)
1572 0 : unlock_page(pages[i]);
1573 0 : page_cache_release(pages[i]);
1574 : }
1575 0 : nr_pages -= ret;
1576 0 : index += ret;
1577 0 : cond_resched();
1578 : }
1579 : }
1580 :
1581 29879 : static noinline int lock_delalloc_pages(struct inode *inode,
1582 : struct page *locked_page,
1583 : u64 delalloc_start,
1584 : u64 delalloc_end)
1585 : {
1586 29879 : unsigned long index = delalloc_start >> PAGE_CACHE_SHIFT;
1587 : unsigned long start_index = index;
1588 29879 : unsigned long end_index = delalloc_end >> PAGE_CACHE_SHIFT;
1589 : unsigned long pages_locked = 0;
1590 : struct page *pages[16];
1591 : unsigned long nrpages;
1592 : int ret;
1593 : int i;
1594 :
1595 : /* the caller is responsible for locking the start index */
1596 29879 : if (index == locked_page->index && index == end_index)
1597 : return 0;
1598 :
1599 : /* skip the page at the start index */
1600 14714 : nrpages = end_index - index + 1;
1601 115205 : while (nrpages > 0) {
1602 85780 : ret = find_get_pages_contig(inode->i_mapping, index,
1603 85780 : min_t(unsigned long,
1604 : nrpages, ARRAY_SIZE(pages)), pages);
1605 85779 : if (ret == 0) {
1606 : ret = -EAGAIN;
1607 : goto done;
1608 : }
1609 : /* now we have an array of pages, lock them all */
1610 1300542 : for (i = 0; i < ret; i++) {
1611 : /*
1612 : * the caller is taking responsibility for
1613 : * locked_page
1614 : */
1615 1300538 : if (pages[i] != locked_page) {
1616 1285819 : lock_page(pages[i]);
1617 3857475 : if (!PageDirty(pages[i]) ||
1618 1285825 : pages[i]->mapping != inode->i_mapping) {
1619 : ret = -EAGAIN;
1620 0 : unlock_page(pages[i]);
1621 0 : page_cache_release(pages[i]);
1622 0 : goto done;
1623 : }
1624 : }
1625 1300544 : page_cache_release(pages[i]);
1626 1300542 : pages_locked++;
1627 : }
1628 85780 : nrpages -= ret;
1629 85780 : index += ret;
1630 85780 : cond_resched();
1631 : }
1632 : ret = 0;
1633 : done:
1634 14714 : if (ret && pages_locked) {
1635 0 : __unlock_for_delalloc(inode, locked_page,
1636 : delalloc_start,
1637 0 : ((u64)(start_index + pages_locked - 1)) <<
1638 : PAGE_CACHE_SHIFT);
1639 : }
1640 14714 : return ret;
1641 : }
1642 :
1643 : /*
1644 : * find a contiguous range of bytes in the file marked as delalloc, not
1645 : * more than 'max_bytes'. start and end are used to return the range,
1646 : *
1647 : * 1 is returned if we find something, 0 if nothing was in the tree
1648 : */
1649 1312842 : STATIC u64 find_lock_delalloc_range(struct inode *inode,
1650 : struct extent_io_tree *tree,
1651 : struct page *locked_page, u64 *start,
1652 : u64 *end, u64 max_bytes)
1653 : {
1654 : u64 delalloc_start;
1655 : u64 delalloc_end;
1656 : u64 found;
1657 1312842 : struct extent_state *cached_state = NULL;
1658 : int ret;
1659 : int loops = 0;
1660 :
1661 : again:
1662 : /* step one, find a bunch of delalloc bytes starting at start */
1663 1312842 : delalloc_start = *start;
1664 1312842 : delalloc_end = 0;
1665 1312842 : found = find_delalloc_range(tree, &delalloc_start, &delalloc_end,
1666 : max_bytes, &cached_state);
1667 1312835 : if (!found || delalloc_end <= *start) {
1668 1282956 : *start = delalloc_start;
1669 1282956 : *end = delalloc_end;
1670 1282956 : free_extent_state(cached_state);
1671 1282987 : return 0;
1672 : }
1673 :
1674 : /*
1675 : * start comes from the offset of locked_page. We have to lock
1676 : * pages in order, so we can't process delalloc bytes before
1677 : * locked_page
1678 : */
1679 29879 : if (delalloc_start < *start)
1680 63 : delalloc_start = *start;
1681 :
1682 : /*
1683 : * make sure to limit the number of pages we try to lock down
1684 : */
1685 29879 : if (delalloc_end + 1 - delalloc_start > max_bytes)
1686 2 : delalloc_end = delalloc_start + max_bytes - 1;
1687 :
1688 : /* step two, lock all the pages after the page that has start */
1689 29879 : ret = lock_delalloc_pages(inode, locked_page,
1690 : delalloc_start, delalloc_end);
1691 29878 : if (ret == -EAGAIN) {
1692 : /* some of the pages are gone, lets avoid looping by
1693 : * shortening the size of the delalloc range we're searching
1694 : */
1695 0 : free_extent_state(cached_state);
1696 0 : cached_state = NULL;
1697 0 : if (!loops) {
1698 : max_bytes = PAGE_CACHE_SIZE;
1699 : loops = 1;
1700 : goto again;
1701 : } else {
1702 : found = 0;
1703 : goto out_failed;
1704 : }
1705 : }
1706 29878 : BUG_ON(ret); /* Only valid values are 0 and -EAGAIN */
1707 :
1708 : /* step three, lock the state bits for the whole range */
1709 29878 : lock_extent_bits(tree, delalloc_start, delalloc_end, 0, &cached_state);
1710 :
1711 : /* then test to make sure it is all still delalloc */
1712 29880 : ret = test_range_bit(tree, delalloc_start, delalloc_end,
1713 : EXTENT_DELALLOC, 1, cached_state);
1714 29881 : if (!ret) {
1715 0 : unlock_extent_cached(tree, delalloc_start, delalloc_end,
1716 : &cached_state, GFP_NOFS);
1717 0 : __unlock_for_delalloc(inode, locked_page,
1718 : delalloc_start, delalloc_end);
1719 0 : cond_resched();
1720 0 : goto again;
1721 : }
1722 29881 : free_extent_state(cached_state);
1723 29881 : *start = delalloc_start;
1724 29881 : *end = delalloc_end;
1725 : out_failed:
1726 29881 : return found;
1727 : }
1728 :
1729 30095 : int extent_clear_unlock_delalloc(struct inode *inode, u64 start, u64 end,
1730 : struct page *locked_page,
1731 : unsigned long clear_bits,
1732 : unsigned long page_ops)
1733 : {
1734 30095 : struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree;
1735 : int ret;
1736 : struct page *pages[16];
1737 30095 : unsigned long index = start >> PAGE_CACHE_SHIFT;
1738 30095 : unsigned long end_index = end >> PAGE_CACHE_SHIFT;
1739 30095 : unsigned long nr_pages = end_index - index + 1;
1740 : int i;
1741 :
1742 30095 : clear_extent_bit(tree, start, end, clear_bits, 1, 0, NULL, GFP_NOFS);
1743 30096 : if (page_ops == 0)
1744 : return 0;
1745 :
1746 131205 : while (nr_pages > 0) {
1747 101111 : ret = find_get_pages_contig(inode->i_mapping, index,
1748 101111 : min_t(unsigned long,
1749 : nr_pages, ARRAY_SIZE(pages)), pages);
1750 1416776 : for (i = 0; i < ret; i++) {
1751 :
1752 1315666 : if (page_ops & PAGE_SET_PRIVATE2)
1753 1308871 : SetPagePrivate2(pages[i]);
1754 :
1755 1315710 : if (pages[i] == locked_page) {
1756 25901 : page_cache_release(pages[i]);
1757 25901 : continue;
1758 : }
1759 1289809 : if (page_ops & PAGE_CLEAR_DIRTY)
1760 6793 : clear_page_dirty_for_io(pages[i]);
1761 1289809 : if (page_ops & PAGE_SET_WRITEBACK)
1762 6793 : set_page_writeback(pages[i]);
1763 1289809 : if (page_ops & PAGE_END_WRITEBACK)
1764 3851 : end_page_writeback(pages[i]);
1765 1289809 : if (page_ops & PAGE_UNLOCK)
1766 1289780 : unlock_page(pages[i]);
1767 1289806 : page_cache_release(pages[i]);
1768 : }
1769 101110 : nr_pages -= ret;
1770 101110 : index += ret;
1771 101110 : cond_resched();
1772 : }
1773 : return 0;
1774 : }
1775 :
1776 : /*
1777 : * count the number of bytes in the tree that have a given bit(s)
1778 : * set. This can be fairly slow, except for EXTENT_DIRTY which is
1779 : * cached. The total number found is returned.
1780 : */
1781 81161 : u64 count_range_bits(struct extent_io_tree *tree,
1782 : u64 *start, u64 search_end, u64 max_bytes,
1783 : unsigned long bits, int contig)
1784 : {
1785 : struct rb_node *node;
1786 : struct extent_state *state;
1787 81161 : u64 cur_start = *start;
1788 : u64 total_bytes = 0;
1789 : u64 last = 0;
1790 : int found = 0;
1791 :
1792 81161 : if (WARN_ON(search_end <= cur_start))
1793 : return 0;
1794 :
1795 : spin_lock(&tree->lock);
1796 81358 : if (cur_start == 0 && bits == EXTENT_DIRTY) {
1797 80670 : total_bytes = tree->dirty_bytes;
1798 80670 : goto out;
1799 : }
1800 : /*
1801 : * this search will find all the extents that end after
1802 : * our range starts.
1803 : */
1804 : node = tree_search(tree, cur_start);
1805 688 : if (!node)
1806 : goto out;
1807 :
1808 : while (1) {
1809 : state = rb_entry(node, struct extent_state, rb_node);
1810 1164 : if (state->start > search_end)
1811 : break;
1812 1087 : if (contig && found && state->start > last + 1)
1813 : break;
1814 1087 : if (state->end >= cur_start && (state->state & bits) == bits) {
1815 146 : total_bytes += min(search_end, state->end) + 1 -
1816 73 : max(cur_start, state->start);
1817 73 : if (total_bytes >= max_bytes)
1818 : break;
1819 66 : if (!found) {
1820 66 : *start = max(cur_start, state->start);
1821 : found = 1;
1822 : }
1823 66 : last = state->end;
1824 1014 : } else if (contig && found) {
1825 : break;
1826 : }
1827 1021 : node = rb_next(node);
1828 1021 : if (!node)
1829 : break;
1830 : }
1831 : out:
1832 : spin_unlock(&tree->lock);
1833 81356 : return total_bytes;
1834 : }
1835 :
1836 : /*
1837 : * set the private field for a given byte offset in the tree. If there isn't
1838 : * an extent_state there already, this does nothing.
1839 : */
1840 0 : static int set_state_private(struct extent_io_tree *tree, u64 start, u64 private)
1841 : {
1842 : struct rb_node *node;
1843 : struct extent_state *state;
1844 : int ret = 0;
1845 :
1846 : spin_lock(&tree->lock);
1847 : /*
1848 : * this search will find all the extents that end after
1849 : * our range starts.
1850 : */
1851 : node = tree_search(tree, start);
1852 0 : if (!node) {
1853 : ret = -ENOENT;
1854 : goto out;
1855 : }
1856 : state = rb_entry(node, struct extent_state, rb_node);
1857 0 : if (state->start != start) {
1858 : ret = -ENOENT;
1859 : goto out;
1860 : }
1861 0 : state->private = private;
1862 : out:
1863 : spin_unlock(&tree->lock);
1864 0 : return ret;
1865 : }
1866 :
1867 0 : int get_state_private(struct extent_io_tree *tree, u64 start, u64 *private)
1868 : {
1869 : struct rb_node *node;
1870 : struct extent_state *state;
1871 : int ret = 0;
1872 :
1873 : spin_lock(&tree->lock);
1874 : /*
1875 : * this search will find all the extents that end after
1876 : * our range starts.
1877 : */
1878 : node = tree_search(tree, start);
1879 0 : if (!node) {
1880 : ret = -ENOENT;
1881 : goto out;
1882 : }
1883 : state = rb_entry(node, struct extent_state, rb_node);
1884 0 : if (state->start != start) {
1885 : ret = -ENOENT;
1886 : goto out;
1887 : }
1888 0 : *private = state->private;
1889 : out:
1890 : spin_unlock(&tree->lock);
1891 0 : return ret;
1892 : }
1893 :
1894 : /*
1895 : * searches a range in the state tree for a given mask.
1896 : * If 'filled' == 1, this returns 1 only if every extent in the tree
1897 : * has the bits set. Otherwise, 1 is returned if any bit in the
1898 : * range is found set.
1899 : */
1900 353484 : int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
1901 : unsigned long bits, int filled, struct extent_state *cached)
1902 : {
1903 : struct extent_state *state = NULL;
1904 : struct rb_node *node;
1905 : int bitset = 0;
1906 :
1907 : spin_lock(&tree->lock);
1908 434797 : if (cached && cached->tree && cached->start <= start &&
1909 81299 : cached->end > start)
1910 81299 : node = &cached->rb_node;
1911 : else
1912 : node = tree_search(tree, start);
1913 353513 : while (node && start <= end) {
1914 : state = rb_entry(node, struct extent_state, rb_node);
1915 :
1916 348935 : if (filled && state->start > start) {
1917 : bitset = 0;
1918 : break;
1919 : }
1920 :
1921 348933 : if (state->start > end)
1922 : break;
1923 :
1924 166806 : if (state->state & bits) {
1925 : bitset = 1;
1926 32129 : if (!filled)
1927 : break;
1928 134677 : } else if (filled) {
1929 : bitset = 0;
1930 : break;
1931 : }
1932 :
1933 33752 : if (state->end == (u64)-1)
1934 : break;
1935 :
1936 33752 : start = state->end + 1;
1937 33752 : if (start > end)
1938 : break;
1939 17 : node = rb_next(node);
1940 17 : if (!node) {
1941 0 : if (filled)
1942 : bitset = 0;
1943 : break;
1944 : }
1945 : }
1946 : spin_unlock(&tree->lock);
1947 353492 : return bitset;
1948 : }
1949 :
1950 : /*
1951 : * helper function to set a given page up to date if all the
1952 : * extents in the tree for that page are up to date
1953 : */
1954 452 : static void check_page_uptodate(struct extent_io_tree *tree, struct page *page)
1955 : {
1956 452 : u64 start = page_offset(page);
1957 452 : u64 end = start + PAGE_CACHE_SIZE - 1;
1958 452 : if (test_range_bit(tree, start, end, EXTENT_UPTODATE, 1, NULL))
1959 : SetPageUptodate(page);
1960 452 : }
1961 :
1962 : /*
1963 : * When IO fails, either with EIO or csum verification fails, we
1964 : * try other mirrors that might have a good copy of the data. This
1965 : * io_failure_record is used to record state as we go through all the
1966 : * mirrors. If another mirror has good data, the page is set up to date
1967 : * and things continue. If a good mirror can't be found, the original
1968 : * bio end_io callback is called to indicate things have failed.
1969 : */
1970 : struct io_failure_record {
1971 : struct page *page;
1972 : u64 start;
1973 : u64 len;
1974 : u64 logical;
1975 : unsigned long bio_flags;
1976 : int this_mirror;
1977 : int failed_mirror;
1978 : int in_validation;
1979 : };
1980 :
1981 0 : static int free_io_failure(struct inode *inode, struct io_failure_record *rec,
1982 : int did_repair)
1983 : {
1984 : int ret;
1985 : int err = 0;
1986 0 : struct extent_io_tree *failure_tree = &BTRFS_I(inode)->io_failure_tree;
1987 :
1988 0 : set_state_private(failure_tree, rec->start, 0);
1989 0 : ret = clear_extent_bits(failure_tree, rec->start,
1990 0 : rec->start + rec->len - 1,
1991 : EXTENT_LOCKED | EXTENT_DIRTY, GFP_NOFS);
1992 0 : if (ret)
1993 : err = ret;
1994 :
1995 0 : ret = clear_extent_bits(&BTRFS_I(inode)->io_tree, rec->start,
1996 0 : rec->start + rec->len - 1,
1997 : EXTENT_DAMAGED, GFP_NOFS);
1998 0 : if (ret && !err)
1999 : err = ret;
2000 :
2001 0 : kfree(rec);
2002 0 : return err;
2003 : }
2004 :
2005 : /*
2006 : * this bypasses the standard btrfs submit functions deliberately, as
2007 : * the standard behavior is to write all copies in a raid setup. here we only
2008 : * want to write the one bad copy. so we do the mapping for ourselves and issue
2009 : * submit_bio directly.
2010 : * to avoid any synchronization issues, wait for the data after writing, which
2011 : * actually prevents the read that triggered the error from finishing.
2012 : * currently, there can be no more than two copies of every data bit. thus,
2013 : * exactly one rewrite is required.
2014 : */
2015 0 : int repair_io_failure(struct btrfs_fs_info *fs_info, u64 start,
2016 0 : u64 length, u64 logical, struct page *page,
2017 : int mirror_num)
2018 : {
2019 : struct bio *bio;
2020 : struct btrfs_device *dev;
2021 0 : u64 map_length = 0;
2022 : u64 sector;
2023 0 : struct btrfs_bio *bbio = NULL;
2024 0 : struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
2025 : int ret;
2026 :
2027 : ASSERT(!(fs_info->sb->s_flags & MS_RDONLY));
2028 0 : BUG_ON(!mirror_num);
2029 :
2030 : /* we can't repair anything in raid56 yet */
2031 0 : if (btrfs_is_parity_mirror(map_tree, logical, length, mirror_num))
2032 : return 0;
2033 :
2034 0 : bio = btrfs_io_bio_alloc(GFP_NOFS, 1);
2035 0 : if (!bio)
2036 : return -EIO;
2037 0 : bio->bi_iter.bi_size = 0;
2038 0 : map_length = length;
2039 :
2040 0 : ret = btrfs_map_block(fs_info, WRITE, logical,
2041 : &map_length, &bbio, mirror_num);
2042 0 : if (ret) {
2043 0 : bio_put(bio);
2044 0 : return -EIO;
2045 : }
2046 0 : BUG_ON(mirror_num != bbio->mirror_num);
2047 0 : sector = bbio->stripes[mirror_num-1].physical >> 9;
2048 0 : bio->bi_iter.bi_sector = sector;
2049 0 : dev = bbio->stripes[mirror_num-1].dev;
2050 0 : kfree(bbio);
2051 0 : if (!dev || !dev->bdev || !dev->writeable) {
2052 0 : bio_put(bio);
2053 0 : return -EIO;
2054 : }
2055 0 : bio->bi_bdev = dev->bdev;
2056 0 : bio_add_page(bio, page, length, start - page_offset(page));
2057 :
2058 0 : if (btrfsic_submit_bio_wait(WRITE_SYNC, bio)) {
2059 : /* try to remap that extent elsewhere? */
2060 0 : bio_put(bio);
2061 0 : btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_WRITE_ERRS);
2062 0 : return -EIO;
2063 : }
2064 :
2065 0 : printk_ratelimited_in_rcu(KERN_INFO
2066 : "BTRFS: read error corrected: ino %lu off %llu "
2067 : "(dev %s sector %llu)\n", page->mapping->host->i_ino,
2068 : start, rcu_str_deref(dev->name), sector);
2069 :
2070 0 : bio_put(bio);
2071 0 : return 0;
2072 : }
2073 :
2074 0 : int repair_eb_io_failure(struct btrfs_root *root, struct extent_buffer *eb,
2075 : int mirror_num)
2076 : {
2077 0 : u64 start = eb->start;
2078 0 : unsigned long i, num_pages = num_extent_pages(eb->start, eb->len);
2079 : int ret = 0;
2080 :
2081 0 : if (root->fs_info->sb->s_flags & MS_RDONLY)
2082 : return -EROFS;
2083 :
2084 0 : for (i = 0; i < num_pages; i++) {
2085 : struct page *p = extent_buffer_page(eb, i);
2086 0 : ret = repair_io_failure(root->fs_info, start, PAGE_CACHE_SIZE,
2087 : start, p, mirror_num);
2088 0 : if (ret)
2089 : break;
2090 0 : start += PAGE_CACHE_SIZE;
2091 : }
2092 :
2093 0 : return ret;
2094 : }
2095 :
2096 : /*
2097 : * each time an IO finishes, we do a fast check in the IO failure tree
2098 : * to see if we need to process or clean up an io_failure_record
2099 : */
2100 80536 : static int clean_io_failure(u64 start, struct page *page)
2101 : {
2102 : u64 private;
2103 : u64 private_failure;
2104 : struct io_failure_record *failrec;
2105 80536 : struct inode *inode = page->mapping->host;
2106 80536 : struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
2107 : struct extent_state *state;
2108 : int num_copies;
2109 : int did_repair = 0;
2110 : int ret;
2111 :
2112 80536 : private = 0;
2113 80536 : ret = count_range_bits(&BTRFS_I(inode)->io_failure_tree, &private,
2114 : (u64)-1, 1, EXTENT_DIRTY, 0);
2115 80646 : if (!ret)
2116 : return 0;
2117 :
2118 0 : ret = get_state_private(&BTRFS_I(inode)->io_failure_tree, start,
2119 : &private_failure);
2120 0 : if (ret)
2121 : return 0;
2122 :
2123 0 : failrec = (struct io_failure_record *)(unsigned long) private_failure;
2124 0 : BUG_ON(!failrec->this_mirror);
2125 :
2126 0 : if (failrec->in_validation) {
2127 : /* there was no real error, just free the record */
2128 0 : pr_debug("clean_io_failure: freeing dummy error at %llu\n",
2129 : failrec->start);
2130 : did_repair = 1;
2131 : goto out;
2132 : }
2133 0 : if (fs_info->sb->s_flags & MS_RDONLY)
2134 : goto out;
2135 :
2136 : spin_lock(&BTRFS_I(inode)->io_tree.lock);
2137 0 : state = find_first_extent_bit_state(&BTRFS_I(inode)->io_tree,
2138 : failrec->start,
2139 : EXTENT_LOCKED);
2140 : spin_unlock(&BTRFS_I(inode)->io_tree.lock);
2141 :
2142 0 : if (state && state->start <= failrec->start &&
2143 0 : state->end >= failrec->start + failrec->len - 1) {
2144 0 : num_copies = btrfs_num_copies(fs_info, failrec->logical,
2145 : failrec->len);
2146 0 : if (num_copies > 1) {
2147 0 : ret = repair_io_failure(fs_info, start, failrec->len,
2148 : failrec->logical, page,
2149 : failrec->failed_mirror);
2150 : did_repair = !ret;
2151 : }
2152 : ret = 0;
2153 : }
2154 :
2155 : out:
2156 0 : if (!ret)
2157 0 : ret = free_io_failure(inode, failrec, did_repair);
2158 :
2159 0 : return ret;
2160 : }
2161 :
2162 : /*
2163 : * this is a generic handler for readpage errors (default
2164 : * readpage_io_failed_hook). if other copies exist, read those and write back
2165 : * good data to the failed position. does not investigate in remapping the
2166 : * failed extent elsewhere, hoping the device will be smart enough to do this as
2167 : * needed
2168 : */
2169 :
2170 0 : static int bio_readpage_error(struct bio *failed_bio, u64 phy_offset,
2171 0 : struct page *page, u64 start, u64 end,
2172 : int failed_mirror)
2173 : {
2174 : struct io_failure_record *failrec = NULL;
2175 : u64 private;
2176 : struct extent_map *em;
2177 0 : struct inode *inode = page->mapping->host;
2178 0 : struct extent_io_tree *failure_tree = &BTRFS_I(inode)->io_failure_tree;
2179 0 : struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree;
2180 0 : struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
2181 : struct bio *bio;
2182 : struct btrfs_io_bio *btrfs_failed_bio;
2183 : struct btrfs_io_bio *btrfs_bio;
2184 : int num_copies;
2185 : int ret;
2186 : int read_mode;
2187 : u64 logical;
2188 :
2189 0 : BUG_ON(failed_bio->bi_rw & REQ_WRITE);
2190 :
2191 0 : ret = get_state_private(failure_tree, start, &private);
2192 0 : if (ret) {
2193 0 : failrec = kzalloc(sizeof(*failrec), GFP_NOFS);
2194 0 : if (!failrec)
2195 : return -ENOMEM;
2196 0 : failrec->start = start;
2197 0 : failrec->len = end - start + 1;
2198 0 : failrec->this_mirror = 0;
2199 0 : failrec->bio_flags = 0;
2200 0 : failrec->in_validation = 0;
2201 :
2202 0 : read_lock(&em_tree->lock);
2203 0 : em = lookup_extent_mapping(em_tree, start, failrec->len);
2204 0 : if (!em) {
2205 : read_unlock(&em_tree->lock);
2206 0 : kfree(failrec);
2207 0 : return -EIO;
2208 : }
2209 :
2210 0 : if (em->start > start || em->start + em->len <= start) {
2211 0 : free_extent_map(em);
2212 : em = NULL;
2213 : }
2214 : read_unlock(&em_tree->lock);
2215 :
2216 0 : if (!em) {
2217 0 : kfree(failrec);
2218 0 : return -EIO;
2219 : }
2220 0 : logical = start - em->start;
2221 0 : logical = em->block_start + logical;
2222 0 : if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
2223 : logical = em->block_start;
2224 0 : failrec->bio_flags = EXTENT_BIO_COMPRESSED;
2225 0 : extent_set_compress_type(&failrec->bio_flags,
2226 0 : em->compress_type);
2227 : }
2228 0 : pr_debug("bio_readpage_error: (new) logical=%llu, start=%llu, "
2229 : "len=%llu\n", logical, start, failrec->len);
2230 0 : failrec->logical = logical;
2231 0 : free_extent_map(em);
2232 :
2233 : /* set the bits in the private failure tree */
2234 : ret = set_extent_bits(failure_tree, start, end,
2235 : EXTENT_LOCKED | EXTENT_DIRTY, GFP_NOFS);
2236 0 : if (ret >= 0)
2237 0 : ret = set_state_private(failure_tree, start,
2238 : (u64)(unsigned long)failrec);
2239 : /* set the bits in the inode's tree */
2240 0 : if (ret >= 0)
2241 : ret = set_extent_bits(tree, start, end, EXTENT_DAMAGED,
2242 : GFP_NOFS);
2243 0 : if (ret < 0) {
2244 0 : kfree(failrec);
2245 0 : return ret;
2246 : }
2247 : } else {
2248 0 : failrec = (struct io_failure_record *)(unsigned long)private;
2249 0 : pr_debug("bio_readpage_error: (found) logical=%llu, "
2250 : "start=%llu, len=%llu, validation=%d\n",
2251 : failrec->logical, failrec->start, failrec->len,
2252 : failrec->in_validation);
2253 : /*
2254 : * when data can be on disk more than twice, add to failrec here
2255 : * (e.g. with a list for failed_mirror) to make
2256 : * clean_io_failure() clean all those errors at once.
2257 : */
2258 : }
2259 0 : num_copies = btrfs_num_copies(BTRFS_I(inode)->root->fs_info,
2260 : failrec->logical, failrec->len);
2261 0 : if (num_copies == 1) {
2262 : /*
2263 : * we only have a single copy of the data, so don't bother with
2264 : * all the retry and error correction code that follows. no
2265 : * matter what the error is, it is very likely to persist.
2266 : */
2267 0 : pr_debug("bio_readpage_error: cannot repair, num_copies=%d, next_mirror %d, failed_mirror %d\n",
2268 : num_copies, failrec->this_mirror, failed_mirror);
2269 0 : free_io_failure(inode, failrec, 0);
2270 0 : return -EIO;
2271 : }
2272 :
2273 : /*
2274 : * there are two premises:
2275 : * a) deliver good data to the caller
2276 : * b) correct the bad sectors on disk
2277 : */
2278 0 : if (failed_bio->bi_vcnt > 1) {
2279 : /*
2280 : * to fulfill b), we need to know the exact failing sectors, as
2281 : * we don't want to rewrite any more than the failed ones. thus,
2282 : * we need separate read requests for the failed bio
2283 : *
2284 : * if the following BUG_ON triggers, our validation request got
2285 : * merged. we need separate requests for our algorithm to work.
2286 : */
2287 0 : BUG_ON(failrec->in_validation);
2288 0 : failrec->in_validation = 1;
2289 0 : failrec->this_mirror = failed_mirror;
2290 : read_mode = READ_SYNC | REQ_FAILFAST_DEV;
2291 : } else {
2292 : /*
2293 : * we're ready to fulfill a) and b) alongside. get a good copy
2294 : * of the failed sector and if we succeed, we have setup
2295 : * everything for repair_io_failure to do the rest for us.
2296 : */
2297 0 : if (failrec->in_validation) {
2298 0 : BUG_ON(failrec->this_mirror != failed_mirror);
2299 0 : failrec->in_validation = 0;
2300 0 : failrec->this_mirror = 0;
2301 : }
2302 0 : failrec->failed_mirror = failed_mirror;
2303 0 : failrec->this_mirror++;
2304 0 : if (failrec->this_mirror == failed_mirror)
2305 0 : failrec->this_mirror++;
2306 : read_mode = READ_SYNC;
2307 : }
2308 :
2309 0 : if (failrec->this_mirror > num_copies) {
2310 0 : pr_debug("bio_readpage_error: (fail) num_copies=%d, next_mirror %d, failed_mirror %d\n",
2311 : num_copies, failrec->this_mirror, failed_mirror);
2312 0 : free_io_failure(inode, failrec, 0);
2313 0 : return -EIO;
2314 : }
2315 :
2316 0 : bio = btrfs_io_bio_alloc(GFP_NOFS, 1);
2317 0 : if (!bio) {
2318 0 : free_io_failure(inode, failrec, 0);
2319 0 : return -EIO;
2320 : }
2321 0 : bio->bi_end_io = failed_bio->bi_end_io;
2322 0 : bio->bi_iter.bi_sector = failrec->logical >> 9;
2323 0 : bio->bi_bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
2324 0 : bio->bi_iter.bi_size = 0;
2325 :
2326 : btrfs_failed_bio = btrfs_io_bio(failed_bio);
2327 0 : if (btrfs_failed_bio->csum) {
2328 0 : struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
2329 0 : u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
2330 :
2331 : btrfs_bio = btrfs_io_bio(bio);
2332 0 : btrfs_bio->csum = btrfs_bio->csum_inline;
2333 0 : phy_offset >>= inode->i_sb->s_blocksize_bits;
2334 0 : phy_offset *= csum_size;
2335 0 : memcpy(btrfs_bio->csum, btrfs_failed_bio->csum + phy_offset,
2336 : csum_size);
2337 : }
2338 :
2339 0 : bio_add_page(bio, page, failrec->len, start - page_offset(page));
2340 :
2341 0 : pr_debug("bio_readpage_error: submitting new read[%#x] to "
2342 : "this_mirror=%d, num_copies=%d, in_validation=%d\n", read_mode,
2343 : failrec->this_mirror, num_copies, failrec->in_validation);
2344 :
2345 0 : ret = tree->ops->submit_bio_hook(inode, read_mode, bio,
2346 : failrec->this_mirror,
2347 : failrec->bio_flags, 0);
2348 0 : return ret;
2349 : }
2350 :
2351 : /* lots and lots of room for performance fixes in the end_bio funcs */
2352 :
2353 1308880 : int end_extent_writepage(struct page *page, int err, u64 start, u64 end)
2354 : {
2355 1308880 : int uptodate = (err == 0);
2356 : struct extent_io_tree *tree;
2357 : int ret = 0;
2358 :
2359 1308880 : tree = &BTRFS_I(page->mapping->host)->io_tree;
2360 :
2361 1308880 : if (tree->ops && tree->ops->writepage_end_io_hook) {
2362 1308880 : ret = tree->ops->writepage_end_io_hook(page, start,
2363 : end, NULL, uptodate);
2364 1308916 : if (ret)
2365 : uptodate = 0;
2366 : }
2367 :
2368 1308916 : if (!uptodate) {
2369 : ClearPageUptodate(page);
2370 : SetPageError(page);
2371 0 : ret = ret < 0 ? ret : -EIO;
2372 0 : mapping_set_error(page->mapping, ret);
2373 : }
2374 1308916 : return 0;
2375 : }
2376 :
2377 : /*
2378 : * after a writepage IO is done, we need to:
2379 : * clear the uptodate bits on error
2380 : * clear the writeback bits in the extent tree for this IO
2381 : * end_page_writeback if the page has no more pending IO
2382 : *
2383 : * Scheduling is not allowed, so the extent state tree is expected
2384 : * to have one and only one object corresponding to this IO.
2385 : */
2386 65676 : static void end_bio_extent_writepage(struct bio *bio, int err)
2387 : {
2388 : struct bio_vec *bvec;
2389 : u64 start;
2390 : u64 end;
2391 : int i;
2392 :
2393 1374571 : bio_for_each_segment_all(bvec, bio, i) {
2394 2617774 : struct page *page = bvec->bv_page;
2395 :
2396 : /* We always issue full-page reads, but if some block
2397 : * in a page fails to read, blk_update_request() will
2398 : * advance bv_offset and adjust bv_len to compensate.
2399 : * Print a warning for nonzero offsets, and an error
2400 : * if they don't add up to a full page. */
2401 1308887 : if (bvec->bv_offset || bvec->bv_len != PAGE_CACHE_SIZE) {
2402 0 : if (bvec->bv_offset + bvec->bv_len != PAGE_CACHE_SIZE)
2403 0 : btrfs_err(BTRFS_I(page->mapping->host)->root->fs_info,
2404 : "partial page write in btrfs with offset %u and length %u",
2405 : bvec->bv_offset, bvec->bv_len);
2406 : else
2407 0 : btrfs_info(BTRFS_I(page->mapping->host)->root->fs_info,
2408 : "incomplete page write in btrfs with offset %u and "
2409 : "length %u",
2410 : bvec->bv_offset, bvec->bv_len);
2411 : }
2412 :
2413 1308887 : start = page_offset(page);
2414 1308887 : end = start + bvec->bv_offset + bvec->bv_len - 1;
2415 :
2416 1308887 : if (end_extent_writepage(page, err, start, end))
2417 0 : continue;
2418 :
2419 1308916 : end_page_writeback(page);
2420 : }
2421 :
2422 65684 : bio_put(bio);
2423 65683 : }
2424 :
2425 : static void
2426 29590 : endio_readpage_release_extent(struct extent_io_tree *tree, u64 start, u64 len,
2427 : int uptodate)
2428 : {
2429 29590 : struct extent_state *cached = NULL;
2430 29590 : u64 end = start + len - 1;
2431 :
2432 29590 : if (uptodate && tree->track_uptodate)
2433 : set_extent_uptodate(tree, start, end, &cached, GFP_ATOMIC);
2434 : unlock_extent_cached(tree, start, end, &cached, GFP_ATOMIC);
2435 29591 : }
2436 :
2437 : /*
2438 : * after a readpage IO is done, we need to:
2439 : * clear the uptodate bits on error
2440 : * set the uptodate bits if things worked
2441 : * set the page up to date if all extents in the tree are uptodate
2442 : * clear the lock bit in the extent tree
2443 : * unlock the page if there are no other extents locked for it
2444 : *
2445 : * Scheduling is not allowed, so the extent state tree is expected
2446 : * to have one and only one object corresponding to this IO.
2447 : */
2448 28580 : static void end_bio_extent_readpage(struct bio *bio, int err)
2449 : {
2450 : struct bio_vec *bvec;
2451 : int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
2452 28580 : struct btrfs_io_bio *io_bio = btrfs_io_bio(bio);
2453 : struct extent_io_tree *tree;
2454 : u64 offset = 0;
2455 : u64 start;
2456 : u64 end;
2457 : u64 len;
2458 : u64 extent_start = 0;
2459 : u64 extent_len = 0;
2460 : int mirror;
2461 : int ret;
2462 : int i;
2463 :
2464 28580 : if (err)
2465 : uptodate = 0;
2466 :
2467 109239 : bio_for_each_segment_all(bvec, bio, i) {
2468 161282 : struct page *page = bvec->bv_page;
2469 161289 : struct inode *inode = page->mapping->host;
2470 :
2471 80660 : pr_debug("end_bio_extent_readpage: bi_sector=%llu, err=%d, "
2472 : "mirror=%lu\n", (u64)bio->bi_iter.bi_sector, err,
2473 : io_bio->mirror_num);
2474 80622 : tree = &BTRFS_I(inode)->io_tree;
2475 :
2476 : /* We always issue full-page reads, but if some block
2477 : * in a page fails to read, blk_update_request() will
2478 : * advance bv_offset and adjust bv_len to compensate.
2479 : * Print a warning for nonzero offsets, and an error
2480 : * if they don't add up to a full page. */
2481 80622 : if (bvec->bv_offset || bvec->bv_len != PAGE_CACHE_SIZE) {
2482 0 : if (bvec->bv_offset + bvec->bv_len != PAGE_CACHE_SIZE)
2483 0 : btrfs_err(BTRFS_I(page->mapping->host)->root->fs_info,
2484 : "partial page read in btrfs with offset %u and length %u",
2485 : bvec->bv_offset, bvec->bv_len);
2486 : else
2487 0 : btrfs_info(BTRFS_I(page->mapping->host)->root->fs_info,
2488 : "incomplete page read in btrfs with offset %u and "
2489 : "length %u",
2490 : bvec->bv_offset, bvec->bv_len);
2491 : }
2492 :
2493 80622 : start = page_offset(page);
2494 80622 : end = start + bvec->bv_offset + bvec->bv_len - 1;
2495 : len = bvec->bv_len;
2496 :
2497 80622 : mirror = io_bio->mirror_num;
2498 80622 : if (likely(uptodate && tree->ops &&
2499 : tree->ops->readpage_end_io_hook)) {
2500 80631 : ret = tree->ops->readpage_end_io_hook(io_bio, offset,
2501 : page, start, end,
2502 : mirror);
2503 80537 : if (ret)
2504 : uptodate = 0;
2505 : else
2506 80538 : clean_io_failure(start, page);
2507 : }
2508 :
2509 80629 : if (likely(uptodate))
2510 : goto readpage_ok;
2511 :
2512 0 : if (tree->ops && tree->ops->readpage_io_failed_hook) {
2513 0 : ret = tree->ops->readpage_io_failed_hook(page, mirror);
2514 0 : if (!ret && !err &&
2515 : test_bit(BIO_UPTODATE, &bio->bi_flags))
2516 : uptodate = 1;
2517 : } else {
2518 : /*
2519 : * The generic bio_readpage_error handles errors the
2520 : * following way: If possible, new read requests are
2521 : * created and submitted and will end up in
2522 : * end_bio_extent_readpage as well (if we're lucky, not
2523 : * in the !uptodate case). In that case it returns 0 and
2524 : * we just go on with the next page in our bio. If it
2525 : * can't handle the error it will return -EIO and we
2526 : * remain responsible for that page.
2527 : */
2528 0 : ret = bio_readpage_error(bio, offset, page, start, end,
2529 : mirror);
2530 0 : if (ret == 0) {
2531 : uptodate =
2532 : test_bit(BIO_UPTODATE, &bio->bi_flags);
2533 0 : if (err)
2534 : uptodate = 0;
2535 0 : offset += len;
2536 0 : continue;
2537 : }
2538 : }
2539 : readpage_ok:
2540 80629 : if (likely(uptodate)) {
2541 : loff_t i_size = i_size_read(inode);
2542 80629 : pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
2543 : unsigned offset;
2544 :
2545 : /* Zero out the end if this page straddles i_size */
2546 80629 : offset = i_size & (PAGE_CACHE_SIZE-1);
2547 80629 : if (page->index == end_index && offset)
2548 : zero_user_segment(page, offset, PAGE_CACHE_SIZE);
2549 : SetPageUptodate(page);
2550 : } else {
2551 : ClearPageUptodate(page);
2552 : SetPageError(page);
2553 : }
2554 80657 : unlock_page(page);
2555 80656 : offset += len;
2556 :
2557 80656 : if (unlikely(!uptodate)) {
2558 0 : if (extent_len) {
2559 0 : endio_readpage_release_extent(tree,
2560 : extent_start,
2561 : extent_len, 1);
2562 : extent_start = 0;
2563 : extent_len = 0;
2564 : }
2565 0 : endio_readpage_release_extent(tree, start,
2566 0 : end - start + 1, 0);
2567 80656 : } else if (!extent_len) {
2568 : extent_start = start;
2569 28578 : extent_len = end + 1 - start;
2570 52078 : } else if (extent_start + extent_len == start) {
2571 51067 : extent_len += end + 1 - start;
2572 : } else {
2573 1011 : endio_readpage_release_extent(tree, extent_start,
2574 : extent_len, uptodate);
2575 : extent_start = start;
2576 1011 : extent_len = end + 1 - start;
2577 : }
2578 : }
2579 :
2580 28579 : if (extent_len)
2581 28579 : endio_readpage_release_extent(tree, extent_start, extent_len,
2582 : uptodate);
2583 28580 : if (io_bio->end_io)
2584 375 : io_bio->end_io(io_bio, err);
2585 28580 : bio_put(bio);
2586 28580 : }
2587 :
2588 : /*
2589 : * this allocates from the btrfs_bioset. We're returning a bio right now
2590 : * but you can call btrfs_io_bio for the appropriate container_of magic
2591 : */
2592 : struct bio *
2593 122377 : btrfs_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs,
2594 : gfp_t gfp_flags)
2595 : {
2596 : struct btrfs_io_bio *btrfs_bio;
2597 : struct bio *bio;
2598 :
2599 122377 : bio = bio_alloc_bioset(gfp_flags, nr_vecs, btrfs_bioset);
2600 :
2601 122375 : if (bio == NULL && (current->flags & PF_MEMALLOC)) {
2602 1 : while (!bio && (nr_vecs /= 2)) {
2603 0 : bio = bio_alloc_bioset(gfp_flags,
2604 : nr_vecs, btrfs_bioset);
2605 : }
2606 : }
2607 :
2608 122376 : if (bio) {
2609 122376 : bio->bi_bdev = bdev;
2610 122376 : bio->bi_iter.bi_sector = first_sector;
2611 : btrfs_bio = btrfs_io_bio(bio);
2612 122376 : btrfs_bio->csum = NULL;
2613 122376 : btrfs_bio->csum_allocated = NULL;
2614 122376 : btrfs_bio->end_io = NULL;
2615 : }
2616 122376 : return bio;
2617 : }
2618 :
2619 90602 : struct bio *btrfs_bio_clone(struct bio *bio, gfp_t gfp_mask)
2620 : {
2621 90602 : return bio_clone_bioset(bio, gfp_mask, btrfs_bioset);
2622 : }
2623 :
2624 :
2625 : /* this also allocates from the btrfs_bioset */
2626 183799 : struct bio *btrfs_io_bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs)
2627 : {
2628 : struct btrfs_io_bio *btrfs_bio;
2629 : struct bio *bio;
2630 :
2631 183799 : bio = bio_alloc_bioset(gfp_mask, nr_iovecs, btrfs_bioset);
2632 183812 : if (bio) {
2633 : btrfs_bio = btrfs_io_bio(bio);
2634 183809 : btrfs_bio->csum = NULL;
2635 183809 : btrfs_bio->csum_allocated = NULL;
2636 183809 : btrfs_bio->end_io = NULL;
2637 : }
2638 183812 : return bio;
2639 : }
2640 :
2641 :
2642 122182 : static int __must_check submit_one_bio(int rw, struct bio *bio,
2643 : int mirror_num, unsigned long bio_flags)
2644 : {
2645 : int ret = 0;
2646 122182 : struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;
2647 244364 : struct page *page = bvec->bv_page;
2648 122182 : struct extent_io_tree *tree = bio->bi_private;
2649 : u64 start;
2650 :
2651 122182 : start = page_offset(page) + bvec->bv_offset;
2652 :
2653 122182 : bio->bi_private = NULL;
2654 :
2655 122182 : bio_get(bio);
2656 :
2657 122185 : if (tree->ops && tree->ops->submit_bio_hook)
2658 122185 : ret = tree->ops->submit_bio_hook(page->mapping->host, rw, bio,
2659 : mirror_num, bio_flags, start);
2660 : else
2661 0 : btrfsic_submit_bio(rw, bio);
2662 :
2663 122184 : if (bio_flagged(bio, BIO_EOPNOTSUPP))
2664 : ret = -EOPNOTSUPP;
2665 122184 : bio_put(bio);
2666 122185 : return ret;
2667 : }
2668 :
2669 1495689 : static int merge_bio(int rw, struct extent_io_tree *tree, struct page *page,
2670 : unsigned long offset, size_t size, struct bio *bio,
2671 : unsigned long bio_flags)
2672 : {
2673 : int ret = 0;
2674 1495689 : if (tree->ops && tree->ops->merge_bio_hook)
2675 1495690 : ret = tree->ops->merge_bio_hook(rw, page, offset, size, bio,
2676 : bio_flags);
2677 1495708 : BUG_ON(ret < 0);
2678 1495708 : return ret;
2679 :
2680 : }
2681 :
2682 3062299 : static int submit_extent_page(int rw, struct extent_io_tree *tree,
2683 : struct page *page, sector_t sector,
2684 : size_t size, unsigned long offset,
2685 : struct block_device *bdev,
2686 : struct bio **bio_ret,
2687 : unsigned long max_pages,
2688 : bio_end_io_t end_io_func,
2689 : int mirror_num,
2690 : unsigned long prev_bio_flags,
2691 : unsigned long bio_flags)
2692 : {
2693 : int ret = 0;
2694 : struct bio *bio;
2695 : int nr;
2696 : int contig = 0;
2697 1566609 : int this_compressed = bio_flags & EXTENT_BIO_COMPRESSED;
2698 1566609 : int old_compressed = prev_bio_flags & EXTENT_BIO_COMPRESSED;
2699 1566609 : size_t page_size = min_t(size_t, size, PAGE_CACHE_SIZE);
2700 :
2701 1566609 : if (bio_ret && *bio_ret) {
2702 : bio = *bio_ret;
2703 1508257 : if (old_compressed)
2704 297 : contig = bio->bi_iter.bi_sector == sector;
2705 : else
2706 1507960 : contig = bio_end_sector(bio) == sector;
2707 :
2708 3003965 : if (prev_bio_flags != bio_flags || !contig ||
2709 2943355 : merge_bio(rw, tree, page, offset, page_size, bio, bio_flags) ||
2710 1447672 : bio_add_page(bio, page, page_size, offset) < page_size) {
2711 63824 : ret = submit_one_bio(rw, bio, mirror_num,
2712 : prev_bio_flags);
2713 63830 : if (ret < 0)
2714 : return ret;
2715 : bio = NULL;
2716 : } else {
2717 : return 0;
2718 : }
2719 : }
2720 122184 : if (this_compressed)
2721 : nr = BIO_MAX_PAGES;
2722 : else
2723 122142 : nr = bio_get_nr_vecs(bdev);
2724 :
2725 122183 : bio = btrfs_bio_alloc(bdev, sector, nr, GFP_NOFS | __GFP_HIGH);
2726 122181 : if (!bio)
2727 : return -ENOMEM;
2728 :
2729 122181 : bio_add_page(bio, page, page_size, offset);
2730 122183 : bio->bi_end_io = end_io_func;
2731 122183 : bio->bi_private = tree;
2732 :
2733 122183 : if (bio_ret)
2734 122183 : *bio_ret = bio;
2735 : else
2736 0 : ret = submit_one_bio(rw, bio, mirror_num, bio_flags);
2737 :
2738 : return ret;
2739 : }
2740 :
2741 192393 : static void attach_extent_buffer_page(struct extent_buffer *eb,
2742 : struct page *page)
2743 : {
2744 192393 : if (!PagePrivate(page)) {
2745 : SetPagePrivate(page);
2746 192395 : page_cache_get(page);
2747 192394 : set_page_private(page, (unsigned long)eb);
2748 : } else {
2749 0 : WARN_ON(page->private != (unsigned long)eb);
2750 : }
2751 192394 : }
2752 :
2753 3158407 : void set_page_extent_mapped(struct page *page)
2754 : {
2755 3158407 : if (!PagePrivate(page)) {
2756 : SetPagePrivate(page);
2757 1757500 : page_cache_get(page);
2758 1757494 : set_page_private(page, EXTENT_PAGE_PRIVATE);
2759 : }
2760 3158408 : }
2761 :
2762 : static struct extent_map *
2763 462506 : __get_extent_map(struct inode *inode, struct page *page, size_t pg_offset,
2764 : u64 start, u64 len, get_extent_t *get_extent,
2765 : struct extent_map **em_cached)
2766 : {
2767 426247 : struct extent_map *em;
2768 :
2769 462506 : if (em_cached && *em_cached) {
2770 : em = *em_cached;
2771 852494 : if (extent_map_in_tree(em) && start >= em->start &&
2772 : start < extent_map_end(em)) {
2773 418787 : atomic_inc(&em->refs);
2774 418787 : return em;
2775 : }
2776 :
2777 7460 : free_extent_map(em);
2778 7460 : *em_cached = NULL;
2779 : }
2780 :
2781 43719 : em = get_extent(inode, page, pg_offset, start, len, 0);
2782 75276 : if (em_cached && !IS_ERR_OR_NULL(em)) {
2783 31557 : BUG_ON(*em_cached);
2784 31557 : atomic_inc(&em->refs);
2785 31557 : *em_cached = em;
2786 : }
2787 43719 : return em;
2788 : }
2789 : /*
2790 : * basic readpage implementation. Locked extent state structs are inserted
2791 : * into the tree that are removed when the IO is done (by the end_io
2792 : * handlers)
2793 : * XXX JDM: This needs looking at to ensure proper page locking
2794 : */
2795 486456 : static int __do_readpage(struct extent_io_tree *tree,
2796 486456 : struct page *page,
2797 : get_extent_t *get_extent,
2798 : struct extent_map **em_cached,
2799 : struct bio **bio, int mirror_num,
2800 : unsigned long *bio_flags, int rw)
2801 : {
2802 972912 : struct inode *inode = page->mapping->host;
2803 486456 : u64 start = page_offset(page);
2804 486456 : u64 page_end = start + PAGE_CACHE_SIZE - 1;
2805 : u64 end;
2806 : u64 cur = start;
2807 : u64 extent_offset;
2808 486456 : u64 last_byte = i_size_read(inode);
2809 : u64 block_start;
2810 : u64 cur_end;
2811 : sector_t sector;
2812 462506 : struct extent_map *em;
2813 : struct block_device *bdev;
2814 : int ret;
2815 : int nr = 0;
2816 486456 : int parent_locked = *bio_flags & EXTENT_BIO_PARENT_LOCKED;
2817 : size_t pg_offset = 0;
2818 : size_t iosize;
2819 : size_t disk_io_size;
2820 486456 : size_t blocksize = inode->i_sb->s_blocksize;
2821 486456 : unsigned long this_bio_flag = *bio_flags & EXTENT_BIO_PARENT_LOCKED;
2822 :
2823 486456 : set_page_extent_mapped(page);
2824 :
2825 : end = page_end;
2826 486456 : if (!PageUptodate(page)) {
2827 486456 : if (cleancache_get_page(page) == 0) {
2828 0 : BUG_ON(blocksize != PAGE_SIZE);
2829 0 : unlock_extent(tree, start, end);
2830 0 : goto out;
2831 : }
2832 : }
2833 :
2834 486456 : if (page->index == last_byte >> PAGE_CACHE_SHIFT) {
2835 : char *userpage;
2836 8950 : size_t zero_offset = last_byte & (PAGE_CACHE_SIZE - 1);
2837 :
2838 8950 : if (zero_offset) {
2839 3432 : iosize = PAGE_CACHE_SIZE - zero_offset;
2840 : userpage = kmap_atomic(page);
2841 3432 : memset(userpage + zero_offset, 0, iosize);
2842 : flush_dcache_page(page);
2843 : kunmap_atomic(userpage);
2844 : }
2845 : }
2846 948962 : while (cur <= end) {
2847 : unsigned long pnr = (last_byte >> PAGE_CACHE_SHIFT) + 1;
2848 :
2849 486456 : if (cur >= last_byte) {
2850 : char *userpage;
2851 23950 : struct extent_state *cached = NULL;
2852 :
2853 23950 : iosize = PAGE_CACHE_SIZE - pg_offset;
2854 : userpage = kmap_atomic(page);
2855 23950 : memset(userpage + pg_offset, 0, iosize);
2856 : flush_dcache_page(page);
2857 : kunmap_atomic(userpage);
2858 23950 : set_extent_uptodate(tree, cur, cur + iosize - 1,
2859 : &cached, GFP_NOFS);
2860 23950 : if (!parent_locked)
2861 : unlock_extent_cached(tree, cur,
2862 : cur + iosize - 1,
2863 : &cached, GFP_NOFS);
2864 : break;
2865 : }
2866 462506 : em = __get_extent_map(inode, page, pg_offset, cur,
2867 462506 : end - cur + 1, get_extent, em_cached);
2868 462506 : if (IS_ERR_OR_NULL(em)) {
2869 : SetPageError(page);
2870 0 : if (!parent_locked)
2871 0 : unlock_extent(tree, cur, end);
2872 : break;
2873 : }
2874 462506 : extent_offset = cur - em->start;
2875 462506 : BUG_ON(extent_map_end(em) <= cur);
2876 462506 : BUG_ON(end < cur);
2877 :
2878 462506 : if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
2879 332 : this_bio_flag |= EXTENT_BIO_COMPRESSED;
2880 332 : extent_set_compress_type(&this_bio_flag,
2881 332 : em->compress_type);
2882 : }
2883 :
2884 462506 : iosize = min(extent_map_end(em) - cur, end - cur + 1);
2885 462506 : cur_end = min(extent_map_end(em) - 1, end);
2886 462506 : iosize = ALIGN(iosize, blocksize);
2887 462506 : if (this_bio_flag & EXTENT_BIO_COMPRESSED) {
2888 332 : disk_io_size = em->block_len;
2889 332 : sector = em->block_start >> 9;
2890 : } else {
2891 462174 : sector = (em->block_start + extent_offset) >> 9;
2892 : disk_io_size = iosize;
2893 : }
2894 462506 : bdev = em->bdev;
2895 462506 : block_start = em->block_start;
2896 462506 : if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
2897 : block_start = EXTENT_MAP_HOLE;
2898 462506 : free_extent_map(em);
2899 : em = NULL;
2900 :
2901 : /* we've found a hole, just zero and go on */
2902 462506 : if (block_start == EXTENT_MAP_HOLE) {
2903 : char *userpage;
2904 381384 : struct extent_state *cached = NULL;
2905 :
2906 : userpage = kmap_atomic(page);
2907 381384 : memset(userpage + pg_offset, 0, iosize);
2908 : flush_dcache_page(page);
2909 : kunmap_atomic(userpage);
2910 :
2911 381384 : set_extent_uptodate(tree, cur, cur + iosize - 1,
2912 : &cached, GFP_NOFS);
2913 : unlock_extent_cached(tree, cur, cur + iosize - 1,
2914 : &cached, GFP_NOFS);
2915 : cur = cur + iosize;
2916 381384 : pg_offset += iosize;
2917 381384 : continue;
2918 : }
2919 : /* the get_extent function already copied into the page */
2920 81122 : if (test_range_bit(tree, cur, cur_end,
2921 : EXTENT_UPTODATE, 1, NULL)) {
2922 452 : check_page_uptodate(tree, page);
2923 452 : if (!parent_locked)
2924 452 : unlock_extent(tree, cur, cur + iosize - 1);
2925 452 : cur = cur + iosize;
2926 452 : pg_offset += iosize;
2927 452 : continue;
2928 : }
2929 : /* we have an inline extent but it didn't get marked up
2930 : * to date. Error out
2931 : */
2932 80670 : if (block_start == EXTENT_MAP_INLINE) {
2933 : SetPageError(page);
2934 0 : if (!parent_locked)
2935 0 : unlock_extent(tree, cur, cur + iosize - 1);
2936 0 : cur = cur + iosize;
2937 0 : pg_offset += iosize;
2938 0 : continue;
2939 : }
2940 :
2941 : pnr -= page->index;
2942 80670 : ret = submit_extent_page(rw, tree, page,
2943 : sector, disk_io_size, pg_offset,
2944 : bdev, bio, pnr,
2945 : end_bio_extent_readpage, mirror_num,
2946 : *bio_flags,
2947 : this_bio_flag);
2948 80670 : if (!ret) {
2949 80670 : nr++;
2950 80670 : *bio_flags = this_bio_flag;
2951 : } else {
2952 : SetPageError(page);
2953 0 : if (!parent_locked)
2954 0 : unlock_extent(tree, cur, cur + iosize - 1);
2955 : }
2956 80670 : cur = cur + iosize;
2957 80670 : pg_offset += iosize;
2958 : }
2959 : out:
2960 486456 : if (!nr) {
2961 405786 : if (!PageError(page))
2962 : SetPageUptodate(page);
2963 405786 : unlock_page(page);
2964 : }
2965 486456 : return 0;
2966 : }
2967 :
2968 51609 : static inline void __do_contiguous_readpages(struct extent_io_tree *tree,
2969 : struct page *pages[], int nr_pages,
2970 : u64 start, u64 end,
2971 : get_extent_t *get_extent,
2972 : struct extent_map **em_cached,
2973 : struct bio **bio, int mirror_num,
2974 : unsigned long *bio_flags, int rw)
2975 : {
2976 : struct inode *inode;
2977 : struct btrfs_ordered_extent *ordered;
2978 : int index;
2979 :
2980 51609 : inode = pages[0]->mapping->host;
2981 : while (1) {
2982 : lock_extent(tree, start, end);
2983 51609 : ordered = btrfs_lookup_ordered_range(inode, start,
2984 51609 : end - start + 1);
2985 51609 : if (!ordered)
2986 : break;
2987 0 : unlock_extent(tree, start, end);
2988 0 : btrfs_start_ordered_extent(inode, ordered, 1);
2989 0 : btrfs_put_ordered_extent(ordered);
2990 0 : }
2991 :
2992 450344 : for (index = 0; index < nr_pages; index++) {
2993 450344 : __do_readpage(tree, pages[index], get_extent, em_cached, bio,
2994 : mirror_num, bio_flags, rw);
2995 450344 : page_cache_release(pages[index]);
2996 : }
2997 51609 : }
2998 :
2999 49223 : static void __extent_readpages(struct extent_io_tree *tree,
3000 : struct page *pages[],
3001 : int nr_pages, get_extent_t *get_extent,
3002 : struct extent_map **em_cached,
3003 : struct bio **bio, int mirror_num,
3004 : unsigned long *bio_flags, int rw)
3005 : {
3006 : u64 start = 0;
3007 : u64 end = 0;
3008 : u64 page_start;
3009 : int index;
3010 : int first_index = 0;
3011 :
3012 499567 : for (index = 0; index < nr_pages; index++) {
3013 900688 : page_start = page_offset(pages[index]);
3014 450344 : if (!end) {
3015 : start = page_start;
3016 49223 : end = start + PAGE_CACHE_SIZE - 1;
3017 : first_index = index;
3018 401121 : } else if (end + 1 == page_start) {
3019 398735 : end += PAGE_CACHE_SIZE;
3020 : } else {
3021 2386 : __do_contiguous_readpages(tree, &pages[first_index],
3022 : index - first_index, start,
3023 : end, get_extent, em_cached,
3024 : bio, mirror_num, bio_flags,
3025 : rw);
3026 : start = page_start;
3027 2386 : end = start + PAGE_CACHE_SIZE - 1;
3028 : first_index = index;
3029 : }
3030 : }
3031 :
3032 49223 : if (end)
3033 49223 : __do_contiguous_readpages(tree, &pages[first_index],
3034 : index - first_index, start,
3035 : end, get_extent, em_cached, bio,
3036 : mirror_num, bio_flags, rw);
3037 49223 : }
3038 :
3039 36048 : static int __extent_read_full_page(struct extent_io_tree *tree,
3040 36048 : struct page *page,
3041 : get_extent_t *get_extent,
3042 : struct bio **bio, int mirror_num,
3043 : unsigned long *bio_flags, int rw)
3044 : {
3045 36048 : struct inode *inode = page->mapping->host;
3046 : struct btrfs_ordered_extent *ordered;
3047 36048 : u64 start = page_offset(page);
3048 36048 : u64 end = start + PAGE_CACHE_SIZE - 1;
3049 : int ret;
3050 :
3051 : while (1) {
3052 : lock_extent(tree, start, end);
3053 36048 : ordered = btrfs_lookup_ordered_extent(inode, start);
3054 36048 : if (!ordered)
3055 : break;
3056 0 : unlock_extent(tree, start, end);
3057 0 : btrfs_start_ordered_extent(inode, ordered, 1);
3058 0 : btrfs_put_ordered_extent(ordered);
3059 0 : }
3060 :
3061 36048 : ret = __do_readpage(tree, page, get_extent, NULL, bio, mirror_num,
3062 : bio_flags, rw);
3063 36048 : return ret;
3064 : }
3065 :
3066 27771 : int extent_read_full_page(struct extent_io_tree *tree, struct page *page,
3067 : get_extent_t *get_extent, int mirror_num)
3068 : {
3069 27771 : struct bio *bio = NULL;
3070 27771 : unsigned long bio_flags = 0;
3071 : int ret;
3072 :
3073 27771 : ret = __extent_read_full_page(tree, page, get_extent, &bio, mirror_num,
3074 : &bio_flags, READ);
3075 27771 : if (bio)
3076 969 : ret = submit_one_bio(READ, bio, mirror_num, bio_flags);
3077 27771 : return ret;
3078 : }
3079 :
3080 64 : int extent_read_full_page_nolock(struct extent_io_tree *tree, struct page *page,
3081 : get_extent_t *get_extent, int mirror_num)
3082 : {
3083 64 : struct bio *bio = NULL;
3084 64 : unsigned long bio_flags = EXTENT_BIO_PARENT_LOCKED;
3085 : int ret;
3086 :
3087 64 : ret = __do_readpage(tree, page, get_extent, NULL, &bio, mirror_num,
3088 : &bio_flags, READ);
3089 64 : if (bio)
3090 64 : ret = submit_one_bio(READ, bio, mirror_num, bio_flags);
3091 64 : return ret;
3092 : }
3093 :
3094 1485946 : static noinline void update_nr_written(struct page *page,
3095 : struct writeback_control *wbc,
3096 : unsigned long nr_written)
3097 : {
3098 1485946 : wbc->nr_to_write -= nr_written;
3099 2418637 : if (wbc->range_cyclic || (wbc->nr_to_write > 0 &&
3100 1722071 : wbc->range_start == 0 && wbc->range_end == LLONG_MAX))
3101 1342513 : page->mapping->writeback_index = page->index + nr_written;
3102 1485946 : }
3103 :
3104 : /*
3105 : * helper for __extent_writepage, doing all of the delayed allocation setup.
3106 : *
3107 : * This returns 1 if our fill_delalloc function did all the work required
3108 : * to write the page (copy into inline extent). In this case the IO has
3109 : * been started and the page is already unlocked.
3110 : *
3111 : * This returns 0 if all went well (page still locked)
3112 : * This returns < 0 if there were errors (page still locked)
3113 : */
3114 1312952 : static noinline_for_stack int writepage_delalloc(struct inode *inode,
3115 : struct page *page, struct writeback_control *wbc,
3116 : struct extent_page_data *epd,
3117 : u64 delalloc_start,
3118 : unsigned long *nr_written)
3119 : {
3120 1312952 : struct extent_io_tree *tree = epd->tree;
3121 1312952 : u64 page_end = delalloc_start + PAGE_CACHE_SIZE - 1;
3122 : u64 nr_delalloc;
3123 : u64 delalloc_to_write = 0;
3124 1312952 : u64 delalloc_end = 0;
3125 : int ret;
3126 1312952 : int page_started = 0;
3127 :
3128 1312952 : if (epd->extent_locked || !tree->ops || !tree->ops->fill_delalloc)
3129 : return 0;
3130 :
3131 2625685 : while (delalloc_end < page_end) {
3132 1312843 : nr_delalloc = find_lock_delalloc_range(inode, tree,
3133 : page,
3134 : &delalloc_start,
3135 : &delalloc_end,
3136 : 128 * 1024 * 1024);
3137 1312839 : if (nr_delalloc == 0) {
3138 1282958 : delalloc_start = delalloc_end + 1;
3139 1282958 : continue;
3140 : }
3141 29881 : ret = tree->ops->fill_delalloc(inode, page,
3142 : delalloc_start,
3143 : delalloc_end,
3144 : &page_started,
3145 : nr_written);
3146 : /* File system has been set read-only */
3147 29880 : if (ret) {
3148 : SetPageError(page);
3149 : /* fill_delalloc should be return < 0 for error
3150 : * but just in case, we use > 0 here meaning the
3151 : * IO is started, so we don't want to return > 0
3152 : * unless things are going well.
3153 : */
3154 1 : ret = ret < 0 ? ret : -EIO;
3155 : goto done;
3156 : }
3157 : /*
3158 : * delalloc_end is already one less than the total
3159 : * length, so we don't subtract one from
3160 : * PAGE_CACHE_SIZE
3161 : */
3162 59760 : delalloc_to_write += (delalloc_end - delalloc_start +
3163 29880 : PAGE_CACHE_SIZE) >>
3164 : PAGE_CACHE_SHIFT;
3165 29880 : delalloc_start = delalloc_end + 1;
3166 : }
3167 1312842 : if (wbc->nr_to_write < delalloc_to_write) {
3168 : int thresh = 8192;
3169 :
3170 3 : if (delalloc_to_write < thresh * 2)
3171 1 : thresh = delalloc_to_write;
3172 3 : wbc->nr_to_write = min_t(u64, delalloc_to_write,
3173 : thresh);
3174 : }
3175 :
3176 : /* did the fill delalloc function already unlock and start
3177 : * the IO?
3178 : */
3179 1312842 : if (page_started) {
3180 : /*
3181 : * we've unlocked the page, so we can't update
3182 : * the mapping's writeback index, just update
3183 : * nr_to_write.
3184 : */
3185 4059 : wbc->nr_to_write -= *nr_written;
3186 : return 1;
3187 : }
3188 :
3189 : ret = 0;
3190 :
3191 : done:
3192 : return ret;
3193 : }
3194 :
3195 : /*
3196 : * helper for __extent_writepage. This calls the writepage start hooks,
3197 : * and does the loop to map the page into extents and bios.
3198 : *
3199 : * We return 1 if the IO is started and the page is unlocked,
3200 : * 0 if all went well (page still locked)
3201 : * < 0 if there were errors (page still locked)
3202 : */
3203 1308893 : static noinline_for_stack int __extent_writepage_io(struct inode *inode,
3204 1308893 : struct page *page,
3205 : struct writeback_control *wbc,
3206 : struct extent_page_data *epd,
3207 : loff_t i_size,
3208 : unsigned long nr_written,
3209 : int write_flags, int *nr_ret)
3210 : {
3211 1308893 : struct extent_io_tree *tree = epd->tree;
3212 1308893 : u64 start = page_offset(page);
3213 1308893 : u64 page_end = start + PAGE_CACHE_SIZE - 1;
3214 : u64 end;
3215 : u64 cur = start;
3216 : u64 extent_offset;
3217 : u64 block_start;
3218 : u64 iosize;
3219 : sector_t sector;
3220 : struct extent_state *cached_state = NULL;
3221 1308916 : struct extent_map *em;
3222 : struct block_device *bdev;
3223 : size_t pg_offset = 0;
3224 : size_t blocksize;
3225 : int ret = 0;
3226 : int nr = 0;
3227 : bool compressed;
3228 :
3229 1308893 : if (tree->ops && tree->ops->writepage_start_hook) {
3230 1308894 : ret = tree->ops->writepage_start_hook(page, start,
3231 : page_end);
3232 1308916 : if (ret) {
3233 : /* Fixup worker will requeue */
3234 0 : if (ret == -EBUSY)
3235 0 : wbc->pages_skipped++;
3236 : else
3237 0 : redirty_page_for_writepage(wbc, page);
3238 :
3239 0 : update_nr_written(page, wbc, nr_written);
3240 0 : unlock_page(page);
3241 : ret = 1;
3242 0 : goto done_unlocked;
3243 : }
3244 : }
3245 :
3246 : /*
3247 : * we don't want to touch the inode after unlocking the page,
3248 : * so we update the mapping writeback index now
3249 : */
3250 1308915 : update_nr_written(page, wbc, nr_written + 1);
3251 :
3252 : end = page_end;
3253 1308915 : if (i_size <= start) {
3254 0 : if (tree->ops && tree->ops->writepage_end_io_hook)
3255 0 : tree->ops->writepage_end_io_hook(page, start,
3256 : page_end, NULL, 1);
3257 : goto done;
3258 : }
3259 :
3260 1308915 : blocksize = inode->i_sb->s_blocksize;
3261 :
3262 3926720 : while (cur <= end) {
3263 : u64 em_end;
3264 1308915 : if (cur >= i_size) {
3265 0 : if (tree->ops && tree->ops->writepage_end_io_hook)
3266 0 : tree->ops->writepage_end_io_hook(page, cur,
3267 : page_end, NULL, 1);
3268 : break;
3269 : }
3270 2617830 : em = epd->get_extent(inode, page, pg_offset, cur,
3271 1308915 : end - cur + 1, 1);
3272 1308916 : if (IS_ERR_OR_NULL(em)) {
3273 : SetPageError(page);
3274 : ret = PTR_ERR_OR_ZERO(em);
3275 0 : break;
3276 : }
3277 :
3278 1308916 : extent_offset = cur - em->start;
3279 : em_end = extent_map_end(em);
3280 1308916 : BUG_ON(em_end <= cur);
3281 1308916 : BUG_ON(end < cur);
3282 1308916 : iosize = min(em_end - cur, end - cur + 1);
3283 1308916 : iosize = ALIGN(iosize, blocksize);
3284 1308916 : sector = (em->block_start + extent_offset) >> 9;
3285 1308916 : bdev = em->bdev;
3286 : block_start = em->block_start;
3287 : compressed = test_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
3288 1308916 : free_extent_map(em);
3289 : em = NULL;
3290 :
3291 : /*
3292 : * compressed and inline extents are written through other
3293 : * paths in the FS
3294 : */
3295 1308913 : if (compressed || block_start == EXTENT_MAP_HOLE ||
3296 : block_start == EXTENT_MAP_INLINE) {
3297 : /*
3298 : * end_io notification does not happen here for
3299 : * compressed extents
3300 : */
3301 0 : if (!compressed && tree->ops &&
3302 0 : tree->ops->writepage_end_io_hook)
3303 0 : tree->ops->writepage_end_io_hook(page, cur,
3304 0 : cur + iosize - 1,
3305 : NULL, 1);
3306 0 : else if (compressed) {
3307 : /* we don't want to end_page_writeback on
3308 : * a compressed extent. this happens
3309 : * elsewhere
3310 : */
3311 0 : nr++;
3312 : }
3313 :
3314 0 : cur += iosize;
3315 0 : pg_offset += iosize;
3316 0 : continue;
3317 : }
3318 :
3319 1308913 : if (tree->ops && tree->ops->writepage_io_hook) {
3320 0 : ret = tree->ops->writepage_io_hook(page, cur,
3321 0 : cur + iosize - 1);
3322 : } else {
3323 : ret = 0;
3324 : }
3325 1308913 : if (ret) {
3326 : SetPageError(page);
3327 : } else {
3328 : unsigned long max_nr = (i_size >> PAGE_CACHE_SHIFT) + 1;
3329 :
3330 1308913 : set_range_writeback(tree, cur, cur + iosize - 1);
3331 1308912 : if (!PageWriteback(page)) {
3332 0 : btrfs_err(BTRFS_I(inode)->root->fs_info,
3333 : "page %lu not writeback, cur %llu end %llu",
3334 : page->index, cur, end);
3335 : }
3336 :
3337 1308912 : ret = submit_extent_page(write_flags, tree, page,
3338 : sector, iosize, pg_offset,
3339 : bdev, &epd->bio, max_nr,
3340 : end_bio_extent_writepage,
3341 : 0, 0, 0);
3342 1308890 : if (ret)
3343 : SetPageError(page);
3344 : }
3345 1308890 : cur = cur + iosize;
3346 1308890 : pg_offset += iosize;
3347 1308890 : nr++;
3348 : }
3349 : done:
3350 1308889 : *nr_ret = nr;
3351 :
3352 : done_unlocked:
3353 :
3354 : /* drop our reference on any cached states */
3355 1308889 : free_extent_state(cached_state);
3356 1308888 : return ret;
3357 : }
3358 :
3359 : /*
3360 : * the writepage semantics are similar to regular writepage. extent
3361 : * records are inserted to lock ranges in the tree, and as dirty areas
3362 : * are found, they are marked writeback. Then the lock bits are removed
3363 : * and the end_io handler clears the writeback ranges
3364 : */
3365 2625928 : static int __extent_writepage(struct page *page, struct writeback_control *wbc,
3366 : void *data)
3367 : {
3368 2625928 : struct inode *inode = page->mapping->host;
3369 : struct extent_page_data *epd = data;
3370 1312964 : u64 start = page_offset(page);
3371 1312964 : u64 page_end = start + PAGE_CACHE_SIZE - 1;
3372 : int ret;
3373 1312964 : int nr = 0;
3374 : size_t pg_offset = 0;
3375 : loff_t i_size = i_size_read(inode);
3376 1312964 : unsigned long end_index = i_size >> PAGE_CACHE_SHIFT;
3377 : int write_flags;
3378 1312964 : unsigned long nr_written = 0;
3379 :
3380 1312964 : if (wbc->sync_mode == WB_SYNC_ALL)
3381 : write_flags = WRITE_SYNC;
3382 : else
3383 : write_flags = WRITE;
3384 :
3385 1312964 : trace___extent_writepage(page, inode, wbc);
3386 :
3387 1312965 : WARN_ON(!PageLocked(page));
3388 :
3389 : ClearPageError(page);
3390 :
3391 1312965 : pg_offset = i_size & (PAGE_CACHE_SIZE - 1);
3392 1312965 : if (page->index > end_index ||
3393 10355 : (page->index == end_index && !pg_offset)) {
3394 4 : page->mapping->a_ops->invalidatepage(page, 0, PAGE_CACHE_SIZE);
3395 3 : unlock_page(page);
3396 3 : return 0;
3397 : }
3398 :
3399 1312961 : if (page->index == end_index) {
3400 : char *userpage;
3401 :
3402 : userpage = kmap_atomic(page);
3403 10355 : memset(userpage + pg_offset, 0,
3404 : PAGE_CACHE_SIZE - pg_offset);
3405 : kunmap_atomic(userpage);
3406 : flush_dcache_page(page);
3407 : }
3408 :
3409 : pg_offset = 0;
3410 :
3411 1312961 : set_page_extent_mapped(page);
3412 :
3413 1312952 : ret = writepage_delalloc(inode, page, wbc, epd, start, &nr_written);
3414 1312951 : if (ret == 1)
3415 : goto done_unlocked;
3416 1308893 : if (ret)
3417 : goto done;
3418 :
3419 1308893 : ret = __extent_writepage_io(inode, page, wbc, epd,
3420 : i_size, nr_written, write_flags, &nr);
3421 1308889 : if (ret == 1)
3422 : goto done_unlocked;
3423 :
3424 : done:
3425 1308891 : if (nr == 0) {
3426 : /* make sure the mapping tag for page dirty gets cleared */
3427 : set_page_writeback(page);
3428 0 : end_page_writeback(page);
3429 : }
3430 1308891 : if (PageError(page)) {
3431 0 : ret = ret < 0 ? ret : -EIO;
3432 0 : end_extent_writepage(page, ret, start, page_end);
3433 : }
3434 1308891 : unlock_page(page);
3435 1308901 : return ret;
3436 :
3437 : done_unlocked:
3438 : return 0;
3439 : }
3440 :
3441 0 : void wait_on_extent_buffer_writeback(struct extent_buffer *eb)
3442 : {
3443 45 : wait_on_bit_io(&eb->bflags, EXTENT_BUFFER_WRITEBACK,
3444 : TASK_UNINTERRUPTIBLE);
3445 0 : }
3446 :
3447 : static noinline_for_stack int
3448 57106 : lock_extent_buffer_for_io(struct extent_buffer *eb,
3449 : struct btrfs_fs_info *fs_info,
3450 : struct extent_page_data *epd)
3451 : {
3452 : unsigned long i, num_pages;
3453 : int flush = 0;
3454 : int ret = 0;
3455 :
3456 57106 : if (!btrfs_try_tree_write_lock(eb)) {
3457 : flush = 1;
3458 50 : flush_write_bio(epd);
3459 50 : btrfs_tree_lock(eb);
3460 : }
3461 :
3462 57107 : if (test_bit(EXTENT_BUFFER_WRITEBACK, &eb->bflags)) {
3463 45 : btrfs_tree_unlock(eb);
3464 45 : if (!epd->sync_io)
3465 : return 0;
3466 45 : if (!flush) {
3467 45 : flush_write_bio(epd);
3468 : flush = 1;
3469 : }
3470 : while (1) {
3471 : wait_on_extent_buffer_writeback(eb);
3472 45 : btrfs_tree_lock(eb);
3473 45 : if (!test_bit(EXTENT_BUFFER_WRITEBACK, &eb->bflags))
3474 : break;
3475 0 : btrfs_tree_unlock(eb);
3476 0 : }
3477 : }
3478 :
3479 : /*
3480 : * We need to do this to prevent races in people who check if the eb is
3481 : * under IO since we can end up having no IO bits set for a short period
3482 : * of time.
3483 : */
3484 : spin_lock(&eb->refs_lock);
3485 114213 : if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)) {
3486 : set_bit(EXTENT_BUFFER_WRITEBACK, &eb->bflags);
3487 : spin_unlock(&eb->refs_lock);
3488 : btrfs_set_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN);
3489 114052 : __percpu_counter_add(&fs_info->dirty_metadata_bytes,
3490 57026 : -eb->len,
3491 : fs_info->dirty_metadata_batch);
3492 : ret = 1;
3493 : } else {
3494 : spin_unlock(&eb->refs_lock);
3495 : }
3496 :
3497 57107 : btrfs_tree_unlock(eb);
3498 :
3499 57107 : if (!ret)
3500 : return ret;
3501 :
3502 57026 : num_pages = num_extent_pages(eb->start, eb->len);
3503 234073 : for (i = 0; i < num_pages; i++) {
3504 : struct page *p = extent_buffer_page(eb, i);
3505 :
3506 177047 : if (!trylock_page(p)) {
3507 0 : if (!flush) {
3508 0 : flush_write_bio(epd);
3509 : flush = 1;
3510 : }
3511 0 : lock_page(p);
3512 : }
3513 : }
3514 :
3515 : return ret;
3516 : }
3517 :
3518 57026 : static void end_extent_buffer_writeback(struct extent_buffer *eb)
3519 : {
3520 : clear_bit(EXTENT_BUFFER_WRITEBACK, &eb->bflags);
3521 57026 : smp_mb__after_atomic();
3522 57026 : wake_up_bit(&eb->bflags, EXTENT_BUFFER_WRITEBACK);
3523 57026 : }
3524 :
3525 27921 : static void end_bio_extent_buffer_writepage(struct bio *bio, int err)
3526 : {
3527 : struct bio_vec *bvec;
3528 : struct extent_buffer *eb;
3529 : int i, done;
3530 :
3531 204968 : bio_for_each_segment_all(bvec, bio, i) {
3532 177047 : struct page *page = bvec->bv_page;
3533 :
3534 177047 : eb = (struct extent_buffer *)page->private;
3535 177047 : BUG_ON(!eb);
3536 177047 : done = atomic_dec_and_test(&eb->io_pages);
3537 :
3538 354094 : if (err || test_bit(EXTENT_BUFFER_IOERR, &eb->bflags)) {
3539 : set_bit(EXTENT_BUFFER_IOERR, &eb->bflags);
3540 : ClearPageUptodate(page);
3541 : SetPageError(page);
3542 : }
3543 :
3544 177047 : end_page_writeback(page);
3545 :
3546 177047 : if (!done)
3547 120021 : continue;
3548 :
3549 57026 : end_extent_buffer_writeback(eb);
3550 : }
3551 :
3552 27921 : bio_put(bio);
3553 27921 : }
3554 :
3555 114052 : static noinline_for_stack int write_one_eb(struct extent_buffer *eb,
3556 : struct btrfs_fs_info *fs_info,
3557 : struct writeback_control *wbc,
3558 : struct extent_page_data *epd)
3559 : {
3560 57026 : struct block_device *bdev = fs_info->fs_devices->latest_bdev;
3561 57026 : struct extent_io_tree *tree = &BTRFS_I(fs_info->btree_inode)->io_tree;
3562 57026 : u64 offset = eb->start;
3563 : unsigned long i, num_pages;
3564 : unsigned long bio_flags = 0;
3565 57026 : int rw = (epd->sync_io ? WRITE_SYNC : WRITE) | REQ_META;
3566 : int ret = 0;
3567 :
3568 : clear_bit(EXTENT_BUFFER_IOERR, &eb->bflags);
3569 57026 : num_pages = num_extent_pages(eb->start, eb->len);
3570 57026 : atomic_set(&eb->io_pages, num_pages);
3571 57026 : if (btrfs_header_owner(eb) == BTRFS_TREE_LOG_OBJECTID)
3572 : bio_flags = EXTENT_BIO_TREE_LOG;
3573 :
3574 177047 : for (i = 0; i < num_pages; i++) {
3575 : struct page *p = extent_buffer_page(eb, i);
3576 :
3577 177047 : clear_page_dirty_for_io(p);
3578 : set_page_writeback(p);
3579 177047 : ret = submit_extent_page(rw, tree, p, offset >> 9,
3580 : PAGE_CACHE_SIZE, 0, bdev, &epd->bio,
3581 : -1, end_bio_extent_buffer_writepage,
3582 : 0, epd->bio_flags, bio_flags);
3583 177047 : epd->bio_flags = bio_flags;
3584 177047 : if (ret) {
3585 : set_bit(EXTENT_BUFFER_IOERR, &eb->bflags);
3586 : SetPageError(p);
3587 0 : if (atomic_sub_and_test(num_pages - i, &eb->io_pages))
3588 0 : end_extent_buffer_writeback(eb);
3589 : ret = -EIO;
3590 : break;
3591 : }
3592 177047 : offset += PAGE_CACHE_SIZE;
3593 177047 : update_nr_written(p, wbc, 1);
3594 177047 : unlock_page(p);
3595 : }
3596 :
3597 57026 : if (unlikely(ret)) {
3598 0 : for (; i < num_pages; i++) {
3599 : struct page *p = extent_buffer_page(eb, i);
3600 0 : unlock_page(p);
3601 : }
3602 : }
3603 :
3604 57026 : return ret;
3605 : }
3606 :
3607 21234 : int btree_write_cache_pages(struct address_space *mapping,
3608 : struct writeback_control *wbc)
3609 : {
3610 21234 : struct extent_io_tree *tree = &BTRFS_I(mapping->host)->io_tree;
3611 78260 : struct btrfs_fs_info *fs_info = BTRFS_I(mapping->host)->root->fs_info;
3612 : struct extent_buffer *eb, *prev_eb = NULL;
3613 42468 : struct extent_page_data epd = {
3614 : .bio = NULL,
3615 : .tree = tree,
3616 : .extent_locked = 0,
3617 21234 : .sync_io = wbc->sync_mode == WB_SYNC_ALL,
3618 : .bio_flags = 0,
3619 : };
3620 : int ret = 0;
3621 : int done = 0;
3622 : int nr_to_write_done = 0;
3623 : struct pagevec pvec;
3624 : int nr_pages;
3625 : pgoff_t index;
3626 : pgoff_t end; /* Inclusive */
3627 : int scanned = 0;
3628 : int tag;
3629 :
3630 : pagevec_init(&pvec, 0);
3631 21234 : if (wbc->range_cyclic) {
3632 0 : index = mapping->writeback_index; /* Start from prev offset */
3633 : end = -1;
3634 : } else {
3635 21234 : index = wbc->range_start >> PAGE_CACHE_SHIFT;
3636 21234 : end = wbc->range_end >> PAGE_CACHE_SHIFT;
3637 : scanned = 1;
3638 : }
3639 21234 : if (wbc->sync_mode == WB_SYNC_ALL)
3640 : tag = PAGECACHE_TAG_TOWRITE;
3641 : else
3642 : tag = PAGECACHE_TAG_DIRTY;
3643 : retry:
3644 21234 : if (wbc->sync_mode == WB_SYNC_ALL)
3645 21234 : tag_pages_for_writeback(mapping, index, end);
3646 71732 : while (!done && !nr_to_write_done && (index <= end) &&
3647 29025 : (nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, tag,
3648 29025 : min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1))) {
3649 : unsigned i;
3650 :
3651 : scanned = 1;
3652 163899 : for (i = 0; i < nr_pages; i++) {
3653 163969 : struct page *page = pvec.pages[i];
3654 :
3655 163969 : if (!PagePrivate(page))
3656 0 : continue;
3657 :
3658 163969 : if (!wbc->range_cyclic && page->index > end) {
3659 : done = 1;
3660 : break;
3661 : }
3662 :
3663 : spin_lock(&mapping->private_lock);
3664 163899 : if (!PagePrivate(page)) {
3665 : spin_unlock(&mapping->private_lock);
3666 0 : continue;
3667 : }
3668 :
3669 163899 : eb = (struct extent_buffer *)page->private;
3670 :
3671 : /*
3672 : * Shouldn't happen and normally this would be a BUG_ON
3673 : * but no sense in crashing the users box for something
3674 : * we can survive anyway.
3675 : */
3676 163899 : if (WARN_ON(!eb)) {
3677 : spin_unlock(&mapping->private_lock);
3678 0 : continue;
3679 : }
3680 :
3681 163899 : if (eb == prev_eb) {
3682 : spin_unlock(&mapping->private_lock);
3683 106792 : continue;
3684 : }
3685 :
3686 : ret = atomic_inc_not_zero(&eb->refs);
3687 : spin_unlock(&mapping->private_lock);
3688 57106 : if (!ret)
3689 0 : continue;
3690 :
3691 : prev_eb = eb;
3692 57106 : ret = lock_extent_buffer_for_io(eb, fs_info, &epd);
3693 57107 : if (!ret) {
3694 81 : free_extent_buffer(eb);
3695 81 : continue;
3696 : }
3697 :
3698 57026 : ret = write_one_eb(eb, fs_info, wbc, &epd);
3699 57026 : if (ret) {
3700 : done = 1;
3701 0 : free_extent_buffer(eb);
3702 0 : break;
3703 : }
3704 57026 : free_extent_buffer(eb);
3705 :
3706 : /*
3707 : * the filesystem may choose to bump up nr_to_write.
3708 : * We have to make sure to honor the new nr_to_write
3709 : * at any time
3710 : */
3711 57026 : nr_to_write_done = wbc->nr_to_write <= 0;
3712 : }
3713 : pagevec_release(&pvec);
3714 21473 : cond_resched();
3715 : }
3716 21234 : if (!scanned && !done) {
3717 : /*
3718 : * We hit the last page and there is more work to be done: wrap
3719 : * back to the start of the file
3720 : */
3721 : scanned = 1;
3722 0 : index = 0;
3723 0 : goto retry;
3724 : }
3725 21234 : flush_write_bio(&epd);
3726 21234 : return ret;
3727 : }
3728 :
3729 : /**
3730 : * write_cache_pages - walk the list of dirty pages of the given address space and write all of them.
3731 : * @mapping: address space structure to write
3732 : * @wbc: subtract the number of written pages from *@wbc->nr_to_write
3733 : * @writepage: function called for each page
3734 : * @data: data passed to writepage function
3735 : *
3736 : * If a page is already under I/O, write_cache_pages() skips it, even
3737 : * if it's dirty. This is desirable behaviour for memory-cleaning writeback,
3738 : * but it is INCORRECT for data-integrity system calls such as fsync(). fsync()
3739 : * and msync() need to guarantee that all the data which was dirty at the time
3740 : * the call was made get new I/O started against them. If wbc->sync_mode is
3741 : * WB_SYNC_ALL then we were called for data integrity and we must wait for
3742 : * existing IO to complete.
3743 : */
3744 38221 : static int extent_write_cache_pages(struct extent_io_tree *tree,
3745 : struct address_space *mapping,
3746 : struct writeback_control *wbc,
3747 : writepage_t writepage, void *data,
3748 : void (*flush_fn)(void *))
3749 : {
3750 38221 : struct inode *inode = mapping->host;
3751 : int ret = 0;
3752 : int done = 0;
3753 : int err = 0;
3754 : int nr_to_write_done = 0;
3755 : struct pagevec pvec;
3756 : int nr_pages;
3757 : pgoff_t index;
3758 : pgoff_t end; /* Inclusive */
3759 : int scanned = 0;
3760 : int tag;
3761 :
3762 : /*
3763 : * We have to hold onto the inode so that ordered extents can do their
3764 : * work when the IO finishes. The alternative to this is failing to add
3765 : * an ordered extent if the igrab() fails there and that is a huge pain
3766 : * to deal with, so instead just hold onto the inode throughout the
3767 : * writepages operation. If it fails here we are freeing up the inode
3768 : * anyway and we'd rather not waste our time writing out stuff that is
3769 : * going to be truncated anyway.
3770 : */
3771 38221 : if (!igrab(inode))
3772 : return 0;
3773 :
3774 : pagevec_init(&pvec, 0);
3775 34946 : if (wbc->range_cyclic) {
3776 6687 : index = mapping->writeback_index; /* Start from prev offset */
3777 : end = -1;
3778 : } else {
3779 28259 : index = wbc->range_start >> PAGE_CACHE_SHIFT;
3780 28259 : end = wbc->range_end >> PAGE_CACHE_SHIFT;
3781 : scanned = 1;
3782 : }
3783 34946 : if (wbc->sync_mode == WB_SYNC_ALL)
3784 : tag = PAGECACHE_TAG_TOWRITE;
3785 : else
3786 : tag = PAGECACHE_TAG_DIRTY;
3787 : retry:
3788 35056 : if (wbc->sync_mode == WB_SYNC_ALL)
3789 17387 : tag_pages_for_writeback(mapping, index, end);
3790 286121 : while (!done && !nr_to_write_done && (index <= end) &&
3791 142502 : (nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, tag,
3792 142502 : min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1))) {
3793 : unsigned i;
3794 :
3795 : scanned = 1;
3796 1314224 : for (i = 0; i < nr_pages; i++) {
3797 1314224 : struct page *page = pvec.pages[i];
3798 :
3799 : /*
3800 : * At this point we hold neither mapping->tree_lock nor
3801 : * lock on the page itself: the page may be truncated or
3802 : * invalidated (changing page->mapping to NULL), or even
3803 : * swizzled back from swapper_space to tmpfs file
3804 : * mapping
3805 : */
3806 1314237 : if (!trylock_page(page)) {
3807 154 : flush_fn(data);
3808 154 : lock_page(page);
3809 : }
3810 :
3811 1314237 : if (unlikely(page->mapping != mapping)) {
3812 0 : unlock_page(page);
3813 0 : continue;
3814 : }
3815 :
3816 1314237 : if (!wbc->range_cyclic && page->index > end) {
3817 : done = 1;
3818 0 : unlock_page(page);
3819 0 : continue;
3820 : }
3821 :
3822 1314237 : if (wbc->sync_mode != WB_SYNC_NONE) {
3823 199209 : if (PageWriteback(page))
3824 29 : flush_fn(data);
3825 199209 : wait_on_page_writeback(page);
3826 : }
3827 :
3828 2627377 : if (PageWriteback(page) ||
3829 1313154 : !clear_page_dirty_for_io(page)) {
3830 1365 : unlock_page(page);
3831 1367 : continue;
3832 : }
3833 :
3834 1312858 : ret = (*writepage)(page, wbc, data);
3835 :
3836 1312858 : if (unlikely(ret == AOP_WRITEPAGE_ACTIVATE)) {
3837 0 : unlock_page(page);
3838 : ret = 0;
3839 : }
3840 1312857 : if (!err && ret < 0)
3841 : err = ret;
3842 :
3843 : /*
3844 : * the filesystem may choose to bump up nr_to_write.
3845 : * We have to make sure to honor the new nr_to_write
3846 : * at any time
3847 : */
3848 1312857 : nr_to_write_done = wbc->nr_to_write <= 0;
3849 : }
3850 : pagevec_release(&pvec);
3851 108565 : cond_resched();
3852 : }
3853 35054 : if (!scanned && !done && !err) {
3854 : /*
3855 : * We hit the last page and there is more work to be done: wrap
3856 : * back to the start of the file
3857 : */
3858 : scanned = 1;
3859 110 : index = 0;
3860 : goto retry;
3861 : }
3862 34944 : btrfs_add_delayed_iput(inode);
3863 : return err;
3864 : }
3865 :
3866 59814 : static void flush_epd_write_bio(struct extent_page_data *epd)
3867 : {
3868 59814 : if (epd->bio) {
3869 : int rw = WRITE;
3870 : int ret;
3871 :
3872 31855 : if (epd->sync_io)
3873 : rw = WRITE_SYNC;
3874 :
3875 31855 : ret = submit_one_bio(rw, epd->bio, 0, epd->bio_flags);
3876 31855 : BUG_ON(ret < 0); /* -ENOMEM */
3877 31855 : epd->bio = NULL;
3878 : }
3879 59814 : }
3880 :
3881 21511 : static noinline void flush_write_bio(void *data)
3882 : {
3883 : struct extent_page_data *epd = data;
3884 21511 : flush_epd_write_bio(epd);
3885 21512 : }
3886 :
3887 0 : int extent_write_full_page(struct extent_io_tree *tree, struct page *page,
3888 : get_extent_t *get_extent,
3889 : struct writeback_control *wbc)
3890 : {
3891 : int ret;
3892 0 : struct extent_page_data epd = {
3893 : .bio = NULL,
3894 : .tree = tree,
3895 : .get_extent = get_extent,
3896 : .extent_locked = 0,
3897 0 : .sync_io = wbc->sync_mode == WB_SYNC_ALL,
3898 : .bio_flags = 0,
3899 : };
3900 :
3901 0 : ret = __extent_writepage(page, wbc, &epd);
3902 :
3903 0 : flush_epd_write_bio(&epd);
3904 0 : return ret;
3905 : }
3906 :
3907 81 : int extent_write_locked_range(struct extent_io_tree *tree, struct inode *inode,
3908 : u64 start, u64 end, get_extent_t *get_extent,
3909 : int mode)
3910 : {
3911 : int ret = 0;
3912 81 : struct address_space *mapping = inode->i_mapping;
3913 : struct page *page;
3914 81 : unsigned long nr_pages = (end - start + PAGE_CACHE_SIZE) >>
3915 : PAGE_CACHE_SHIFT;
3916 :
3917 162 : struct extent_page_data epd = {
3918 : .bio = NULL,
3919 : .tree = tree,
3920 : .get_extent = get_extent,
3921 : .extent_locked = 1,
3922 81 : .sync_io = mode == WB_SYNC_ALL,
3923 : .bio_flags = 0,
3924 : };
3925 243 : struct writeback_control wbc_writepages = {
3926 : .sync_mode = mode,
3927 81 : .nr_to_write = nr_pages * 2,
3928 : .range_start = start,
3929 81 : .range_end = end + 1,
3930 : };
3931 :
3932 270 : while (start <= end) {
3933 108 : page = find_get_page(mapping, start >> PAGE_CACHE_SHIFT);
3934 108 : if (clear_page_dirty_for_io(page))
3935 108 : ret = __extent_writepage(page, &wbc_writepages, &epd);
3936 : else {
3937 0 : if (tree->ops && tree->ops->writepage_end_io_hook)
3938 0 : tree->ops->writepage_end_io_hook(page, start,
3939 : start + PAGE_CACHE_SIZE - 1,
3940 : NULL, 1);
3941 0 : unlock_page(page);
3942 : }
3943 108 : page_cache_release(page);
3944 108 : start += PAGE_CACHE_SIZE;
3945 : }
3946 :
3947 81 : flush_epd_write_bio(&epd);
3948 81 : return ret;
3949 : }
3950 :
3951 38223 : int extent_writepages(struct extent_io_tree *tree,
3952 : struct address_space *mapping,
3953 : get_extent_t *get_extent,
3954 : struct writeback_control *wbc)
3955 : {
3956 : int ret = 0;
3957 76446 : struct extent_page_data epd = {
3958 : .bio = NULL,
3959 : .tree = tree,
3960 : .get_extent = get_extent,
3961 : .extent_locked = 0,
3962 38223 : .sync_io = wbc->sync_mode == WB_SYNC_ALL,
3963 : .bio_flags = 0,
3964 : };
3965 :
3966 38223 : ret = extent_write_cache_pages(tree, mapping, wbc,
3967 : __extent_writepage, &epd,
3968 : flush_write_bio);
3969 38223 : flush_epd_write_bio(&epd);
3970 38224 : return ret;
3971 : }
3972 :
3973 24097 : int extent_readpages(struct extent_io_tree *tree,
3974 : struct address_space *mapping,
3975 : struct list_head *pages, unsigned nr_pages,
3976 : get_extent_t get_extent)
3977 : {
3978 24097 : struct bio *bio = NULL;
3979 : unsigned page_idx;
3980 24097 : unsigned long bio_flags = 0;
3981 : struct page *pagepool[16];
3982 : struct page *page;
3983 24097 : struct extent_map *em_cached = NULL;
3984 : int nr = 0;
3985 :
3986 474441 : for (page_idx = 0; page_idx < nr_pages; page_idx++) {
3987 450344 : page = list_entry(pages->prev, struct page, lru);
3988 :
3989 450344 : prefetchw(&page->flags);
3990 450344 : list_del(&page->lru);
3991 450344 : if (add_to_page_cache_lru(page, mapping,
3992 : page->index, GFP_NOFS)) {
3993 0 : page_cache_release(page);
3994 0 : continue;
3995 : }
3996 :
3997 450344 : pagepool[nr++] = page;
3998 450344 : if (nr < ARRAY_SIZE(pagepool))
3999 424185 : continue;
4000 26159 : __extent_readpages(tree, pagepool, nr, get_extent, &em_cached,
4001 : &bio, 0, &bio_flags, READ);
4002 : nr = 0;
4003 : }
4004 24097 : if (nr)
4005 23064 : __extent_readpages(tree, pagepool, nr, get_extent, &em_cached,
4006 : &bio, 0, &bio_flags, READ);
4007 :
4008 24097 : if (em_cached)
4009 24097 : free_extent_map(em_cached);
4010 :
4011 24097 : BUG_ON(!list_empty(pages));
4012 24097 : if (bio)
4013 23283 : return submit_one_bio(READ, bio, 0, bio_flags);
4014 : return 0;
4015 : }
4016 :
4017 : /*
4018 : * basic invalidatepage code, this waits on any locked or writeback
4019 : * ranges corresponding to the page, and then deletes any extent state
4020 : * records from the tree
4021 : */
4022 1335 : int extent_invalidatepage(struct extent_io_tree *tree,
4023 1335 : struct page *page, unsigned long offset)
4024 : {
4025 1335 : struct extent_state *cached_state = NULL;
4026 1335 : u64 start = page_offset(page);
4027 1335 : u64 end = start + PAGE_CACHE_SIZE - 1;
4028 1335 : size_t blocksize = page->mapping->host->i_sb->s_blocksize;
4029 :
4030 1335 : start += ALIGN(offset, blocksize);
4031 1335 : if (start > end)
4032 : return 0;
4033 :
4034 1335 : lock_extent_bits(tree, start, end, 0, &cached_state);
4035 1335 : wait_on_page_writeback(page);
4036 1335 : clear_extent_bit(tree, start, end,
4037 : EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC |
4038 : EXTENT_DO_ACCOUNTING,
4039 : 1, 1, &cached_state, GFP_NOFS);
4040 1335 : return 0;
4041 : }
4042 :
4043 : /*
4044 : * a helper for releasepage, this tests for areas of the page that
4045 : * are locked or under IO and drops the related state bits if it is safe
4046 : * to drop the page.
4047 : */
4048 188224 : static int try_release_extent_state(struct extent_map_tree *map,
4049 : struct extent_io_tree *tree,
4050 188224 : struct page *page, gfp_t mask)
4051 : {
4052 188224 : u64 start = page_offset(page);
4053 188224 : u64 end = start + PAGE_CACHE_SIZE - 1;
4054 : int ret = 1;
4055 :
4056 188224 : if (test_range_bit(tree, start, end,
4057 : EXTENT_IOBITS, 0, NULL))
4058 : ret = 0;
4059 : else {
4060 188224 : if ((mask & GFP_NOFS) == GFP_NOFS)
4061 : mask = GFP_NOFS;
4062 : /*
4063 : * at this point we can safely clear everything except the
4064 : * locked bit and the nodatasum bit
4065 : */
4066 188224 : ret = clear_extent_bit(tree, start, end,
4067 : ~(EXTENT_LOCKED | EXTENT_NODATASUM),
4068 : 0, 0, NULL, mask);
4069 :
4070 : /* if clear_extent_bit failed for enomem reasons,
4071 : * we can't allow the release to continue.
4072 : */
4073 188224 : if (ret < 0)
4074 : ret = 0;
4075 : else
4076 : ret = 1;
4077 : }
4078 188224 : return ret;
4079 : }
4080 :
4081 : /*
4082 : * a helper for releasepage. As long as there are no locked extents
4083 : * in the range corresponding to the page, both state records and extent
4084 : * map records are removed
4085 : */
4086 188224 : int try_release_extent_mapping(struct extent_map_tree *map,
4087 188224 : struct extent_io_tree *tree, struct page *page,
4088 : gfp_t mask)
4089 : {
4090 0 : struct extent_map *em;
4091 188224 : u64 start = page_offset(page);
4092 188224 : u64 end = start + PAGE_CACHE_SIZE - 1;
4093 :
4094 375172 : if ((mask & __GFP_WAIT) &&
4095 186948 : page->mapping->host->i_size > 16 * 1024 * 1024) {
4096 : u64 len;
4097 0 : while (start <= end) {
4098 0 : len = end - start + 1;
4099 0 : write_lock(&map->lock);
4100 0 : em = lookup_extent_mapping(map, start, len);
4101 0 : if (!em) {
4102 : write_unlock(&map->lock);
4103 : break;
4104 : }
4105 0 : if (test_bit(EXTENT_FLAG_PINNED, &em->flags) ||
4106 0 : em->start != start) {
4107 : write_unlock(&map->lock);
4108 0 : free_extent_map(em);
4109 0 : break;
4110 : }
4111 0 : if (!test_range_bit(tree, em->start,
4112 : extent_map_end(em) - 1,
4113 : EXTENT_LOCKED | EXTENT_WRITEBACK,
4114 : 0, NULL)) {
4115 0 : remove_extent_mapping(map, em);
4116 : /* once for the rb tree */
4117 0 : free_extent_map(em);
4118 : }
4119 : start = extent_map_end(em);
4120 : write_unlock(&map->lock);
4121 :
4122 : /* once for us */
4123 0 : free_extent_map(em);
4124 : }
4125 : }
4126 188224 : return try_release_extent_state(map, tree, page, mask);
4127 : }
4128 :
4129 : /*
4130 : * helper function for fiemap, which doesn't want to see any holes.
4131 : * This maps until we find something past 'last'
4132 : */
4133 1030 : static struct extent_map *get_extent_skip_holes(struct inode *inode,
4134 : u64 offset,
4135 : u64 last,
4136 : get_extent_t *get_extent)
4137 : {
4138 1030 : u64 sectorsize = BTRFS_I(inode)->root->sectorsize;
4139 409 : struct extent_map *em;
4140 : u64 len;
4141 :
4142 1030 : if (offset >= last)
4143 : return NULL;
4144 :
4145 : while (1) {
4146 1096 : len = last - offset;
4147 1096 : if (len == 0)
4148 : break;
4149 1096 : len = ALIGN(len, sectorsize);
4150 1096 : em = get_extent(inode, NULL, 0, offset, len, 0);
4151 1095 : if (IS_ERR_OR_NULL(em))
4152 : return em;
4153 :
4154 : /* if this isn't a hole return it */
4155 2190 : if (!test_bit(EXTENT_FLAG_VACANCY, &em->flags) &&
4156 1094 : em->block_start != EXTENT_MAP_HOLE) {
4157 : return em;
4158 : }
4159 :
4160 : /* this is a hole, advance to the next extent */
4161 : offset = extent_map_end(em);
4162 409 : free_extent_map(em);
4163 409 : if (offset >= last)
4164 : break;
4165 : }
4166 : return NULL;
4167 : }
4168 :
4169 1120 : static noinline int count_ext_ref(u64 inum, u64 offset, u64 root_id, void *ctx)
4170 : {
4171 1120 : unsigned long cnt = *((unsigned long *)ctx);
4172 :
4173 1120 : cnt++;
4174 1120 : *((unsigned long *)ctx) = cnt;
4175 :
4176 : /* Now we're sure that the extent is shared. */
4177 1120 : if (cnt > 1)
4178 : return 1;
4179 629 : return 0;
4180 : }
4181 :
4182 688 : int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
4183 : __u64 start, __u64 len, get_extent_t *get_extent)
4184 : {
4185 : int ret = 0;
4186 : u64 off = start;
4187 344 : u64 max = start + len;
4188 : u32 flags = 0;
4189 : u32 found_type;
4190 : u64 last;
4191 : u64 last_for_get_extent = 0;
4192 : u64 disko = 0;
4193 344 : u64 isize = i_size_read(inode);
4194 : struct btrfs_key found_key;
4195 686 : struct extent_map *em = NULL;
4196 344 : struct extent_state *cached_state = NULL;
4197 : struct btrfs_path *path;
4198 : int end = 0;
4199 : u64 em_start = 0;
4200 : u64 em_len = 0;
4201 : u64 em_end = 0;
4202 :
4203 344 : if (len == 0)
4204 : return -EINVAL;
4205 :
4206 344 : path = btrfs_alloc_path();
4207 344 : if (!path)
4208 : return -ENOMEM;
4209 344 : path->leave_spinning = 1;
4210 :
4211 344 : start = round_down(start, BTRFS_I(inode)->root->sectorsize);
4212 344 : len = round_up(max, BTRFS_I(inode)->root->sectorsize) - start;
4213 :
4214 : /*
4215 : * lookup the last file extent. We're not using i_size here
4216 : * because there might be preallocation past i_size
4217 : */
4218 344 : ret = btrfs_lookup_file_extent(NULL, BTRFS_I(inode)->root,
4219 : path, btrfs_ino(inode), -1, 0);
4220 344 : if (ret < 0) {
4221 0 : btrfs_free_path(path);
4222 0 : return ret;
4223 : }
4224 344 : WARN_ON(!ret);
4225 344 : path->slots[0]--;
4226 344 : btrfs_item_key_to_cpu(path->nodes[0], &found_key, path->slots[0]);
4227 344 : found_type = btrfs_key_type(&found_key);
4228 :
4229 : /* No extents, but there might be delalloc bits */
4230 688 : if (found_key.objectid != btrfs_ino(inode) ||
4231 : found_type != BTRFS_EXTENT_DATA_KEY) {
4232 : /* have to trust i_size as the end */
4233 : last = (u64)-1;
4234 : last_for_get_extent = isize;
4235 : } else {
4236 : /*
4237 : * remember the start of the last extent. There are a
4238 : * bunch of different factors that go into the length of the
4239 : * extent, so its much less complex to remember where it started
4240 : */
4241 298 : last = found_key.offset;
4242 298 : last_for_get_extent = last + 1;
4243 : }
4244 344 : btrfs_release_path(path);
4245 :
4246 : /*
4247 : * we might have some extents allocated but more delalloc past those
4248 : * extents. so, we trust isize unless the start of the last extent is
4249 : * beyond isize
4250 : */
4251 344 : if (last < isize) {
4252 : last = (u64)-1;
4253 : last_for_get_extent = isize;
4254 : }
4255 :
4256 344 : lock_extent_bits(&BTRFS_I(inode)->io_tree, start, start + len - 1, 0,
4257 : &cached_state);
4258 :
4259 344 : em = get_extent_skip_holes(inode, start, last_for_get_extent,
4260 : get_extent);
4261 343 : if (!em)
4262 : goto out;
4263 217 : if (IS_ERR(em)) {
4264 0 : ret = PTR_ERR(em);
4265 0 : goto out;
4266 : }
4267 :
4268 686 : while (!end) {
4269 : u64 offset_in_extent = 0;
4270 :
4271 : /* break if the extent we found is outside the range */
4272 1372 : if (em->start >= max || extent_map_end(em) < off)
4273 : break;
4274 :
4275 : /*
4276 : * get_extent may return an extent that starts before our
4277 : * requested range. We have to make sure the ranges
4278 : * we return to fiemap always move forward and don't
4279 : * overlap, so adjust the offsets here
4280 : */
4281 687 : em_start = max(em->start, off);
4282 :
4283 : /*
4284 : * record the offset from the start of the extent
4285 : * for adjusting the disk offset below. Only do this if the
4286 : * extent isn't compressed since our in ram offset may be past
4287 : * what we have actually allocated on disk.
4288 : */
4289 687 : if (!test_bit(EXTENT_FLAG_COMPRESSED, &em->flags))
4290 682 : offset_in_extent = em_start - em->start;
4291 : em_end = extent_map_end(em);
4292 687 : em_len = em_end - em_start;
4293 : disko = 0;
4294 : flags = 0;
4295 :
4296 : /*
4297 : * bump off for our next call to get_extent
4298 : */
4299 : off = extent_map_end(em);
4300 687 : if (off >= max)
4301 : end = 1;
4302 :
4303 687 : if (em->block_start == EXTENT_MAP_LAST_BYTE) {
4304 : end = 1;
4305 : flags |= FIEMAP_EXTENT_LAST;
4306 686 : } else if (em->block_start == EXTENT_MAP_INLINE) {
4307 : flags |= (FIEMAP_EXTENT_DATA_INLINE |
4308 : FIEMAP_EXTENT_NOT_ALIGNED);
4309 686 : } else if (em->block_start == EXTENT_MAP_DELALLOC) {
4310 : flags |= (FIEMAP_EXTENT_DELALLOC |
4311 : FIEMAP_EXTENT_UNKNOWN);
4312 : } else {
4313 677 : unsigned long ref_cnt = 0;
4314 :
4315 677 : disko = em->block_start + offset_in_extent;
4316 :
4317 : /*
4318 : * As btrfs supports shared space, this information
4319 : * can be exported to userspace tools via
4320 : * flag FIEMAP_EXTENT_SHARED.
4321 : */
4322 677 : ret = iterate_inodes_from_logical(
4323 : em->block_start,
4324 677 : BTRFS_I(inode)->root->fs_info,
4325 : path, count_ext_ref, &ref_cnt);
4326 677 : if (ret < 0 && ret != -ENOENT)
4327 : goto out_free;
4328 :
4329 677 : if (ref_cnt > 1)
4330 : flags |= FIEMAP_EXTENT_SHARED;
4331 : }
4332 687 : if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags))
4333 5 : flags |= FIEMAP_EXTENT_ENCODED;
4334 :
4335 687 : free_extent_map(em);
4336 : em = NULL;
4337 1330 : if ((em_start >= last) || em_len == (u64)-1 ||
4338 643 : (last == (u64)-1 && isize <= em_end)) {
4339 191 : flags |= FIEMAP_EXTENT_LAST;
4340 : end = 1;
4341 : }
4342 :
4343 : /* now scan forward to see if this is really the last extent. */
4344 687 : em = get_extent_skip_holes(inode, off, last_for_get_extent,
4345 : get_extent);
4346 687 : if (IS_ERR(em)) {
4347 0 : ret = PTR_ERR(em);
4348 0 : goto out;
4349 : }
4350 687 : if (!em) {
4351 217 : flags |= FIEMAP_EXTENT_LAST;
4352 : end = 1;
4353 : }
4354 687 : ret = fiemap_fill_next_extent(fieinfo, em_start, disko,
4355 : em_len, flags);
4356 687 : if (ret)
4357 : goto out_free;
4358 : }
4359 : out_free:
4360 217 : free_extent_map(em);
4361 : out:
4362 343 : btrfs_free_path(path);
4363 : unlock_extent_cached(&BTRFS_I(inode)->io_tree, start, start + len - 1,
4364 : &cached_state, GFP_NOFS);
4365 344 : return ret;
4366 : }
4367 :
4368 : static void __free_extent_buffer(struct extent_buffer *eb)
4369 : {
4370 : btrfs_leak_debug_del(&eb->leak_list);
4371 61440 : kmem_cache_free(extent_buffer_cache, eb);
4372 : }
4373 :
4374 0 : int extent_buffer_under_io(struct extent_buffer *eb)
4375 : {
4376 122471 : return (atomic_read(&eb->io_pages) ||
4377 245879 : test_bit(EXTENT_BUFFER_WRITEBACK, &eb->bflags) ||
4378 : test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
4379 : }
4380 :
4381 : /*
4382 : * Helper for releasing extent buffer page.
4383 : */
4384 61460 : static void btrfs_release_extent_buffer_page(struct extent_buffer *eb,
4385 : unsigned long start_idx)
4386 : {
4387 : unsigned long index;
4388 : unsigned long num_pages;
4389 : struct page *page;
4390 61460 : int mapped = !test_bit(EXTENT_BUFFER_DUMMY, &eb->bflags);
4391 :
4392 61460 : BUG_ON(extent_buffer_under_io(eb));
4393 :
4394 61460 : num_pages = num_extent_pages(eb->start, eb->len);
4395 61460 : index = start_idx + num_pages;
4396 61460 : if (start_idx >= index)
4397 61461 : return;
4398 :
4399 : do {
4400 191186 : index--;
4401 : page = extent_buffer_page(eb, index);
4402 191186 : if (page && mapped) {
4403 188257 : spin_lock(&page->mapping->private_lock);
4404 : /*
4405 : * We do this since we'll remove the pages after we've
4406 : * removed the eb from the radix tree, so we could race
4407 : * and have this page now attached to the new eb. So
4408 : * only clear page_private if it's still connected to
4409 : * this eb.
4410 : */
4411 376518 : if (PagePrivate(page) &&
4412 188259 : page->private == (unsigned long)eb) {
4413 188259 : BUG_ON(test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
4414 188259 : BUG_ON(PageDirty(page));
4415 188259 : BUG_ON(PageWriteback(page));
4416 : /*
4417 : * We need to make sure we haven't be attached
4418 : * to a new eb.
4419 : */
4420 : ClearPagePrivate(page);
4421 188258 : set_page_private(page, 0);
4422 : /* One for the page private */
4423 188258 : page_cache_release(page);
4424 : }
4425 188258 : spin_unlock(&page->mapping->private_lock);
4426 :
4427 : }
4428 191185 : if (page) {
4429 : /* One for when we alloced the page */
4430 191185 : page_cache_release(page);
4431 : }
4432 191187 : } while (index != start_idx);
4433 : }
4434 :
4435 : /*
4436 : * Helper for releasing the extent buffer.
4437 : */
4438 0 : static inline void btrfs_release_extent_buffer(struct extent_buffer *eb)
4439 : {
4440 0 : btrfs_release_extent_buffer_page(eb, 0);
4441 : __free_extent_buffer(eb);
4442 0 : }
4443 :
4444 : static struct extent_buffer *
4445 61762 : __alloc_extent_buffer(struct btrfs_fs_info *fs_info, u64 start,
4446 : unsigned long len, gfp_t mask)
4447 : {
4448 : struct extent_buffer *eb = NULL;
4449 :
4450 61762 : eb = kmem_cache_zalloc(extent_buffer_cache, mask);
4451 61760 : if (eb == NULL)
4452 : return NULL;
4453 61760 : eb->start = start;
4454 61760 : eb->len = len;
4455 61760 : eb->fs_info = fs_info;
4456 61760 : eb->bflags = 0;
4457 61760 : rwlock_init(&eb->lock);
4458 : atomic_set(&eb->write_locks, 0);
4459 : atomic_set(&eb->read_locks, 0);
4460 : atomic_set(&eb->blocking_readers, 0);
4461 : atomic_set(&eb->blocking_writers, 0);
4462 : atomic_set(&eb->spinning_readers, 0);
4463 : atomic_set(&eb->spinning_writers, 0);
4464 61760 : eb->lock_nested = 0;
4465 61760 : init_waitqueue_head(&eb->write_lock_wq);
4466 61760 : init_waitqueue_head(&eb->read_lock_wq);
4467 :
4468 : btrfs_leak_debug_add(&eb->leak_list, &buffers);
4469 :
4470 61760 : spin_lock_init(&eb->refs_lock);
4471 : atomic_set(&eb->refs, 1);
4472 : atomic_set(&eb->io_pages, 0);
4473 :
4474 : /*
4475 : * Sanity checks, currently the maximum is 64k covered by 16x 4k pages
4476 : */
4477 : BUILD_BUG_ON(BTRFS_MAX_METADATA_BLOCKSIZE
4478 : > MAX_INLINE_EXTENT_BUFFER_SIZE);
4479 61760 : BUG_ON(len > MAX_INLINE_EXTENT_BUFFER_SIZE);
4480 :
4481 : return eb;
4482 : }
4483 :
4484 731 : struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src)
4485 : {
4486 : unsigned long i;
4487 : struct page *p;
4488 : struct extent_buffer *new;
4489 731 : unsigned long num_pages = num_extent_pages(src->start, src->len);
4490 :
4491 731 : new = __alloc_extent_buffer(NULL, src->start, src->len, GFP_NOFS);
4492 731 : if (new == NULL)
4493 : return NULL;
4494 :
4495 2924 : for (i = 0; i < num_pages; i++) {
4496 : p = alloc_page(GFP_NOFS);
4497 2924 : if (!p) {
4498 0 : btrfs_release_extent_buffer(new);
4499 0 : return NULL;
4500 : }
4501 2924 : attach_extent_buffer_page(new, p);
4502 2924 : WARN_ON(PageDirty(p));
4503 : SetPageUptodate(p);
4504 2924 : new->pages[i] = p;
4505 : }
4506 :
4507 731 : copy_extent_buffer(new, src, 0, 0, src->len);
4508 : set_bit(EXTENT_BUFFER_UPTODATE, &new->bflags);
4509 : set_bit(EXTENT_BUFFER_DUMMY, &new->bflags);
4510 :
4511 731 : return new;
4512 : }
4513 :
4514 1 : struct extent_buffer *alloc_dummy_extent_buffer(u64 start, unsigned long len)
4515 : {
4516 1 : struct extent_buffer *eb;
4517 : unsigned long num_pages = num_extent_pages(0, len);
4518 : unsigned long i;
4519 :
4520 1 : eb = __alloc_extent_buffer(NULL, start, len, GFP_NOFS);
4521 1 : if (!eb)
4522 : return NULL;
4523 :
4524 4 : for (i = 0; i < num_pages; i++) {
4525 4 : eb->pages[i] = alloc_page(GFP_NOFS);
4526 4 : if (!eb->pages[i])
4527 : goto err;
4528 : }
4529 1 : set_extent_buffer_uptodate(eb);
4530 : btrfs_set_header_nritems(eb, 0);
4531 : set_bit(EXTENT_BUFFER_DUMMY, &eb->bflags);
4532 :
4533 1 : return eb;
4534 : err:
4535 0 : for (; i > 0; i--)
4536 0 : __free_page(eb->pages[i - 1]);
4537 : __free_extent_buffer(eb);
4538 0 : return NULL;
4539 : }
4540 :
4541 4657738 : static void check_buffer_tree_ref(struct extent_buffer *eb)
4542 : {
4543 : int refs;
4544 : /* the ref bit is tricky. We have to make sure it is set
4545 : * if we have the buffer dirty. Otherwise the
4546 : * code to free a buffer can end up dropping a dirty
4547 : * page
4548 : *
4549 : * Once the ref bit is set, it won't go away while the
4550 : * buffer is dirty or in writeback, and it also won't
4551 : * go away while we have the reference count on the
4552 : * eb bumped.
4553 : *
4554 : * We can't just set the ref bit without bumping the
4555 : * ref on the eb because free_extent_buffer might
4556 : * see the ref bit and try to clear it. If this happens
4557 : * free_extent_buffer might end up dropping our original
4558 : * ref by mistake and freeing the page before we are able
4559 : * to add one more ref.
4560 : *
4561 : * So bump the ref count first, then set the bit. If someone
4562 : * beat us to it, drop the ref we added.
4563 : */
4564 : refs = atomic_read(&eb->refs);
4565 9254688 : if (refs >= 2 && test_bit(EXTENT_BUFFER_TREE_REF, &eb->bflags))
4566 4657982 : return;
4567 :
4568 : spin_lock(&eb->refs_lock);
4569 122066 : if (!test_and_set_bit(EXTENT_BUFFER_TREE_REF, &eb->bflags))
4570 61033 : atomic_inc(&eb->refs);
4571 : spin_unlock(&eb->refs_lock);
4572 : }
4573 :
4574 3432902 : static void mark_extent_buffer_accessed(struct extent_buffer *eb,
4575 : struct page *accessed)
4576 : {
4577 : unsigned long num_pages, i;
4578 :
4579 3432902 : check_buffer_tree_ref(eb);
4580 :
4581 3432447 : num_pages = num_extent_pages(eb->start, eb->len);
4582 16298546 : for (i = 0; i < num_pages; i++) {
4583 : struct page *p = extent_buffer_page(eb, i);
4584 12865934 : if (p != accessed)
4585 12865933 : mark_page_accessed(p);
4586 : }
4587 3432612 : }
4588 :
4589 3493030 : struct extent_buffer *find_extent_buffer(struct btrfs_fs_info *fs_info,
4590 : u64 start)
4591 : {
4592 : struct extent_buffer *eb;
4593 :
4594 : rcu_read_lock();
4595 3493044 : eb = radix_tree_lookup(&fs_info->buffer_radix,
4596 3493044 : start >> PAGE_CACHE_SHIFT);
4597 6926565 : if (eb && atomic_inc_not_zero(&eb->refs)) {
4598 : rcu_read_unlock();
4599 3433100 : mark_extent_buffer_accessed(eb, NULL);
4600 3432520 : return eb;
4601 : }
4602 : rcu_read_unlock();
4603 :
4604 61556 : return NULL;
4605 : }
4606 :
4607 : #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
4608 : struct extent_buffer *alloc_test_extent_buffer(struct btrfs_fs_info *fs_info,
4609 : u64 start, unsigned long len)
4610 : {
4611 : struct extent_buffer *eb, *exists = NULL;
4612 : int ret;
4613 :
4614 : eb = find_extent_buffer(fs_info, start);
4615 : if (eb)
4616 : return eb;
4617 : eb = alloc_dummy_extent_buffer(start, len);
4618 : if (!eb)
4619 : return NULL;
4620 : eb->fs_info = fs_info;
4621 : again:
4622 : ret = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM);
4623 : if (ret)
4624 : goto free_eb;
4625 : spin_lock(&fs_info->buffer_lock);
4626 : ret = radix_tree_insert(&fs_info->buffer_radix,
4627 : start >> PAGE_CACHE_SHIFT, eb);
4628 : spin_unlock(&fs_info->buffer_lock);
4629 : radix_tree_preload_end();
4630 : if (ret == -EEXIST) {
4631 : exists = find_extent_buffer(fs_info, start);
4632 : if (exists)
4633 : goto free_eb;
4634 : else
4635 : goto again;
4636 : }
4637 : check_buffer_tree_ref(eb);
4638 : set_bit(EXTENT_BUFFER_IN_TREE, &eb->bflags);
4639 :
4640 : /*
4641 : * We will free dummy extent buffer's if they come into
4642 : * free_extent_buffer with a ref count of 2, but if we are using this we
4643 : * want the buffers to stay in memory until we're done with them, so
4644 : * bump the ref count again.
4645 : */
4646 : atomic_inc(&eb->refs);
4647 : return eb;
4648 : free_eb:
4649 : btrfs_release_extent_buffer(eb);
4650 : return exists;
4651 : }
4652 : #endif
4653 :
4654 1268775 : struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
4655 : u64 start, unsigned long len)
4656 : {
4657 : unsigned long num_pages = num_extent_pages(start, len);
4658 : unsigned long i;
4659 : unsigned long index = start >> PAGE_CACHE_SHIFT;
4660 : struct extent_buffer *eb;
4661 : struct extent_buffer *exists = NULL;
4662 : struct page *p;
4663 1268775 : struct address_space *mapping = fs_info->btree_inode->i_mapping;
4664 : int uptodate = 1;
4665 : int ret;
4666 :
4667 1268775 : eb = find_extent_buffer(fs_info, start);
4668 1268782 : if (eb)
4669 : return eb;
4670 :
4671 61031 : eb = __alloc_extent_buffer(fs_info, start, len, GFP_NOFS);
4672 61028 : if (!eb)
4673 : return NULL;
4674 :
4675 189469 : for (i = 0; i < num_pages; i++, index++) {
4676 : p = find_or_create_page(mapping, index, GFP_NOFS);
4677 189462 : if (!p)
4678 : goto free_eb;
4679 :
4680 : spin_lock(&mapping->private_lock);
4681 189470 : if (PagePrivate(p)) {
4682 : /*
4683 : * We could have already allocated an eb for this page
4684 : * and attached one so lets see if we can get a ref on
4685 : * the existing eb, and if we can we know it's good and
4686 : * we can just return that one, else we know we can just
4687 : * overwrite page->private.
4688 : */
4689 0 : exists = (struct extent_buffer *)p->private;
4690 0 : if (atomic_inc_not_zero(&exists->refs)) {
4691 : spin_unlock(&mapping->private_lock);
4692 0 : unlock_page(p);
4693 0 : page_cache_release(p);
4694 0 : mark_extent_buffer_accessed(exists, p);
4695 0 : goto free_eb;
4696 : }
4697 :
4698 : /*
4699 : * Do this so attach doesn't complain and we need to
4700 : * drop the ref the old guy had.
4701 : */
4702 : ClearPagePrivate(p);
4703 0 : WARN_ON(PageDirty(p));
4704 0 : page_cache_release(p);
4705 : }
4706 189470 : attach_extent_buffer_page(eb, p);
4707 : spin_unlock(&mapping->private_lock);
4708 189470 : WARN_ON(PageDirty(p));
4709 189469 : eb->pages[i] = p;
4710 189469 : if (!PageUptodate(p))
4711 : uptodate = 0;
4712 :
4713 : /*
4714 : * see below about how we avoid a nasty race with release page
4715 : * and why we unlock later
4716 : */
4717 : }
4718 61032 : if (uptodate)
4719 : set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
4720 : again:
4721 61032 : ret = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM);
4722 61031 : if (ret)
4723 : goto free_eb;
4724 :
4725 : spin_lock(&fs_info->buffer_lock);
4726 61032 : ret = radix_tree_insert(&fs_info->buffer_radix,
4727 : start >> PAGE_CACHE_SHIFT, eb);
4728 : spin_unlock(&fs_info->buffer_lock);
4729 : radix_tree_preload_end();
4730 61031 : if (ret == -EEXIST) {
4731 0 : exists = find_extent_buffer(fs_info, start);
4732 0 : if (exists)
4733 : goto free_eb;
4734 : else
4735 : goto again;
4736 : }
4737 : /* add one reference for the tree */
4738 61031 : check_buffer_tree_ref(eb);
4739 : set_bit(EXTENT_BUFFER_IN_TREE, &eb->bflags);
4740 :
4741 : /*
4742 : * there is a race where release page may have
4743 : * tried to find this extent buffer in the radix
4744 : * but failed. It will tell the VM it is safe to
4745 : * reclaim the, and it will clear the page private bit.
4746 : * We must make sure to set the page private bit properly
4747 : * after the extent buffer is in the radix tree so
4748 : * it doesn't get lost
4749 : */
4750 61032 : SetPageChecked(eb->pages[0]);
4751 189468 : for (i = 1; i < num_pages; i++) {
4752 : p = extent_buffer_page(eb, i);
4753 : ClearPageChecked(p);
4754 128436 : unlock_page(p);
4755 : }
4756 61032 : unlock_page(eb->pages[0]);
4757 61031 : return eb;
4758 :
4759 : free_eb:
4760 0 : for (i = 0; i < num_pages; i++) {
4761 0 : if (eb->pages[i])
4762 0 : unlock_page(eb->pages[i]);
4763 : }
4764 :
4765 0 : WARN_ON(!atomic_dec_and_test(&eb->refs));
4766 0 : btrfs_release_extent_buffer(eb);
4767 0 : return exists;
4768 : }
4769 :
4770 61440 : static inline void btrfs_release_extent_buffer_rcu(struct rcu_head *head)
4771 : {
4772 61440 : struct extent_buffer *eb =
4773 : container_of(head, struct extent_buffer, rcu_head);
4774 :
4775 : __free_extent_buffer(eb);
4776 61436 : }
4777 :
4778 : /* Expects to have eb->eb_lock already held */
4779 4671365 : static int release_extent_buffer(struct extent_buffer *eb)
4780 : {
4781 4671365 : WARN_ON(atomic_read(&eb->refs) == 0);
4782 9343137 : if (atomic_dec_and_test(&eb->refs)) {
4783 122922 : if (test_and_clear_bit(EXTENT_BUFFER_IN_TREE, &eb->bflags)) {
4784 60729 : struct btrfs_fs_info *fs_info = eb->fs_info;
4785 :
4786 : spin_unlock(&eb->refs_lock);
4787 :
4788 : spin_lock(&fs_info->buffer_lock);
4789 60729 : radix_tree_delete(&fs_info->buffer_radix,
4790 60729 : eb->start >> PAGE_CACHE_SHIFT);
4791 : spin_unlock(&fs_info->buffer_lock);
4792 : } else {
4793 : spin_unlock(&eb->refs_lock);
4794 : }
4795 :
4796 : /* Should be safe to release our pages at this point */
4797 61461 : btrfs_release_extent_buffer_page(eb, 0);
4798 61461 : call_rcu(&eb->rcu_head, btrfs_release_extent_buffer_rcu);
4799 61461 : return 1;
4800 : }
4801 : spin_unlock(&eb->refs_lock);
4802 :
4803 4610241 : return 0;
4804 : }
4805 :
4806 7021982 : void free_extent_buffer(struct extent_buffer *eb)
4807 : {
4808 : int refs;
4809 : int old;
4810 7021982 : if (!eb)
4811 : return;
4812 :
4813 : while (1) {
4814 : refs = atomic_read(&eb->refs);
4815 7023473 : if (refs <= 3)
4816 : break;
4817 2414965 : old = atomic_cmpxchg(&eb->refs, refs, refs - 1);
4818 2415103 : if (old == refs)
4819 : return;
4820 : }
4821 :
4822 : spin_lock(&eb->refs_lock);
4823 6907331 : if (atomic_read(&eb->refs) == 2 &&
4824 : test_bit(EXTENT_BUFFER_DUMMY, &eb->bflags))
4825 732 : atomic_dec(&eb->refs);
4826 :
4827 6906563 : if (atomic_read(&eb->refs) == 2 &&
4828 10806 : test_bit(EXTENT_BUFFER_STALE, &eb->bflags) &&
4829 10464 : !extent_buffer_under_io(eb) &&
4830 10464 : test_and_clear_bit(EXTENT_BUFFER_TREE_REF, &eb->bflags))
4831 10464 : atomic_dec(&eb->refs);
4832 :
4833 : /*
4834 : * I know this is terrible, but it's temporary until we stop tracking
4835 : * the uptodate bits and such for the extent buffers.
4836 : */
4837 4610018 : release_extent_buffer(eb);
4838 : }
4839 :
4840 53689 : void free_extent_buffer_stale(struct extent_buffer *eb)
4841 : {
4842 53689 : if (!eb)
4843 53687 : return;
4844 :
4845 : spin_lock(&eb->refs_lock);
4846 : set_bit(EXTENT_BUFFER_STALE, &eb->bflags);
4847 :
4848 139185 : if (atomic_read(&eb->refs) == 2 && !extent_buffer_under_io(eb) &&
4849 : test_and_clear_bit(EXTENT_BUFFER_TREE_REF, &eb->bflags))
4850 42310 : atomic_dec(&eb->refs);
4851 53689 : release_extent_buffer(eb);
4852 : }
4853 :
4854 2006 : void clear_extent_buffer_dirty(struct extent_buffer *eb)
4855 : {
4856 : unsigned long i;
4857 : unsigned long num_pages;
4858 : struct page *page;
4859 :
4860 2006 : num_pages = num_extent_pages(eb->start, eb->len);
4861 :
4862 6712 : for (i = 0; i < num_pages; i++) {
4863 : page = extent_buffer_page(eb, i);
4864 4706 : if (!PageDirty(page))
4865 0 : continue;
4866 :
4867 4706 : lock_page(page);
4868 4706 : WARN_ON(!PagePrivate(page));
4869 :
4870 4706 : clear_page_dirty_for_io(page);
4871 4706 : spin_lock_irq(&page->mapping->tree_lock);
4872 4706 : if (!PageDirty(page)) {
4873 4706 : radix_tree_tag_clear(&page->mapping->page_tree,
4874 : page_index(page),
4875 : PAGECACHE_TAG_DIRTY);
4876 : }
4877 4706 : spin_unlock_irq(&page->mapping->tree_lock);
4878 : ClearPageError(page);
4879 4706 : unlock_page(page);
4880 : }
4881 2006 : WARN_ON(atomic_read(&eb->refs) == 0);
4882 2006 : }
4883 :
4884 1165610 : int set_extent_buffer_dirty(struct extent_buffer *eb)
4885 : {
4886 : unsigned long i;
4887 : unsigned long num_pages;
4888 : int was_dirty = 0;
4889 :
4890 1165610 : check_buffer_tree_ref(eb);
4891 :
4892 1165569 : was_dirty = test_and_set_bit(EXTENT_BUFFER_DIRTY, &eb->bflags);
4893 :
4894 1165913 : num_pages = num_extent_pages(eb->start, eb->len);
4895 1165913 : WARN_ON(atomic_read(&eb->refs) == 0);
4896 1165913 : WARN_ON(!test_bit(EXTENT_BUFFER_TREE_REF, &eb->bflags));
4897 :
4898 4015547 : for (i = 0; i < num_pages; i++)
4899 4015207 : set_page_dirty(extent_buffer_page(eb, i));
4900 1166253 : return was_dirty;
4901 : }
4902 :
4903 0 : int clear_extent_buffer_uptodate(struct extent_buffer *eb)
4904 : {
4905 : unsigned long i;
4906 : struct page *page;
4907 : unsigned long num_pages;
4908 :
4909 : clear_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
4910 0 : num_pages = num_extent_pages(eb->start, eb->len);
4911 0 : for (i = 0; i < num_pages; i++) {
4912 : page = extent_buffer_page(eb, i);
4913 0 : if (page)
4914 : ClearPageUptodate(page);
4915 : }
4916 0 : return 0;
4917 : }
4918 :
4919 61290 : int set_extent_buffer_uptodate(struct extent_buffer *eb)
4920 : {
4921 : unsigned long i;
4922 : struct page *page;
4923 : unsigned long num_pages;
4924 :
4925 : set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
4926 61290 : num_pages = num_extent_pages(eb->start, eb->len);
4927 250958 : for (i = 0; i < num_pages; i++) {
4928 : page = extent_buffer_page(eb, i);
4929 : SetPageUptodate(page);
4930 : }
4931 61291 : return 0;
4932 : }
4933 :
4934 3434517 : int extent_buffer_uptodate(struct extent_buffer *eb)
4935 : {
4936 3434517 : return test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
4937 : }
4938 :
4939 1209796 : int read_extent_buffer_pages(struct extent_io_tree *tree,
4940 : struct extent_buffer *eb, u64 start, int wait,
4941 : get_extent_t *get_extent, int mirror_num)
4942 : {
4943 : unsigned long i;
4944 : unsigned long start_i;
4945 : struct page *page;
4946 : int err;
4947 : int ret = 0;
4948 : int locked_pages = 0;
4949 : int all_uptodate = 1;
4950 : unsigned long num_pages;
4951 : unsigned long num_reads = 0;
4952 1209796 : struct bio *bio = NULL;
4953 1209796 : unsigned long bio_flags = 0;
4954 :
4955 1209796 : if (test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags))
4956 : return 0;
4957 :
4958 2189 : if (start) {
4959 0 : WARN_ON(start < eb->start);
4960 0 : start_i = (start >> PAGE_CACHE_SHIFT) -
4961 0 : (eb->start >> PAGE_CACHE_SHIFT);
4962 : } else {
4963 : start_i = 0;
4964 : }
4965 :
4966 2189 : num_pages = num_extent_pages(eb->start, eb->len);
4967 10478 : for (i = start_i; i < num_pages; i++) {
4968 : page = extent_buffer_page(eb, i);
4969 8291 : if (wait == WAIT_NONE) {
4970 221 : if (!trylock_page(page))
4971 : goto unlock_exit;
4972 : } else {
4973 8070 : lock_page(page);
4974 : }
4975 8289 : locked_pages++;
4976 8289 : if (!PageUptodate(page)) {
4977 8277 : num_reads++;
4978 : all_uptodate = 0;
4979 : }
4980 : }
4981 2187 : if (all_uptodate) {
4982 3 : if (start_i == 0)
4983 : set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
4984 : goto unlock_exit;
4985 : }
4986 :
4987 : clear_bit(EXTENT_BUFFER_IOERR, &eb->bflags);
4988 2184 : eb->read_mirror = 0;
4989 2184 : atomic_set(&eb->io_pages, num_reads);
4990 10461 : for (i = start_i; i < num_pages; i++) {
4991 : page = extent_buffer_page(eb, i);
4992 8277 : if (!PageUptodate(page)) {
4993 : ClearPageError(page);
4994 8277 : err = __extent_read_full_page(tree, page,
4995 : get_extent, &bio,
4996 : mirror_num, &bio_flags,
4997 : READ | REQ_META);
4998 8277 : if (err)
4999 : ret = err;
5000 : } else {
5001 0 : unlock_page(page);
5002 : }
5003 : }
5004 :
5005 2184 : if (bio) {
5006 2184 : err = submit_one_bio(READ | REQ_META, bio, mirror_num,
5007 : bio_flags);
5008 2184 : if (err)
5009 : return err;
5010 : }
5011 :
5012 2184 : if (ret || wait != WAIT_COMPLETE)
5013 : return ret;
5014 :
5015 7485 : for (i = start_i; i < num_pages; i++) {
5016 : page = extent_buffer_page(eb, i);
5017 : wait_on_page_locked(page);
5018 7485 : if (!PageUptodate(page))
5019 : ret = -EIO;
5020 : }
5021 :
5022 : return ret;
5023 :
5024 : unlock_exit:
5025 : i = start_i;
5026 22 : while (locked_pages > 0) {
5027 : page = extent_buffer_page(eb, i);
5028 12 : i++;
5029 12 : unlock_page(page);
5030 12 : locked_pages--;
5031 : }
5032 : return ret;
5033 : }
5034 :
5035 12262845 : void read_extent_buffer(struct extent_buffer *eb, void *dstv,
5036 : unsigned long start,
5037 : unsigned long len)
5038 : {
5039 : size_t cur;
5040 : size_t offset;
5041 : struct page *page;
5042 : char *kaddr;
5043 : char *dst = (char *)dstv;
5044 12262845 : size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1);
5045 12262845 : unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT;
5046 :
5047 12262845 : WARN_ON(start > eb->len);
5048 12265417 : WARN_ON(start + len > eb->start + eb->len);
5049 :
5050 12265417 : offset = (start_offset + start) & (PAGE_CACHE_SIZE - 1);
5051 :
5052 36985812 : while (len > 0) {
5053 : page = extent_buffer_page(eb, i);
5054 :
5055 12454978 : cur = min(len, (PAGE_CACHE_SIZE - offset));
5056 : kaddr = page_address(page);
5057 12454978 : memcpy(dst, kaddr + offset, cur);
5058 :
5059 12454978 : dst += cur;
5060 12454978 : len -= cur;
5061 : offset = 0;
5062 12454978 : i++;
5063 : }
5064 12265417 : }
5065 :
5066 208 : int read_extent_buffer_to_user(struct extent_buffer *eb, void __user *dstv,
5067 : unsigned long start,
5068 : unsigned long len)
5069 : {
5070 : size_t cur;
5071 : size_t offset;
5072 : struct page *page;
5073 : char *kaddr;
5074 : char __user *dst = (char __user *)dstv;
5075 208 : size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1);
5076 208 : unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT;
5077 : int ret = 0;
5078 :
5079 208 : WARN_ON(start > eb->len);
5080 208 : WARN_ON(start + len > eb->start + eb->len);
5081 :
5082 208 : offset = (start_offset + start) & (PAGE_CACHE_SIZE - 1);
5083 :
5084 625 : while (len > 0) {
5085 : page = extent_buffer_page(eb, i);
5086 :
5087 209 : cur = min(len, (PAGE_CACHE_SIZE - offset));
5088 : kaddr = page_address(page);
5089 418 : if (copy_to_user(dst, kaddr + offset, cur)) {
5090 : ret = -EFAULT;
5091 : break;
5092 : }
5093 :
5094 209 : dst += cur;
5095 209 : len -= cur;
5096 : offset = 0;
5097 209 : i++;
5098 : }
5099 :
5100 208 : return ret;
5101 : }
5102 :
5103 41588982 : int map_private_extent_buffer(struct extent_buffer *eb, unsigned long start,
5104 : unsigned long min_len, char **map,
5105 : unsigned long *map_start,
5106 : unsigned long *map_len)
5107 : {
5108 : size_t offset = start & (PAGE_CACHE_SIZE - 1);
5109 : char *kaddr;
5110 : struct page *p;
5111 41588982 : size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1);
5112 41588982 : unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT;
5113 41588982 : unsigned long end_i = (start_offset + start + min_len - 1) >>
5114 : PAGE_CACHE_SHIFT;
5115 :
5116 41588982 : if (i != end_i)
5117 : return -EINVAL;
5118 :
5119 41325202 : if (i == 0) {
5120 : offset = start_offset;
5121 22961501 : *map_start = 0;
5122 : } else {
5123 : offset = 0;
5124 18363701 : *map_start = ((u64)i << PAGE_CACHE_SHIFT) - start_offset;
5125 : }
5126 :
5127 41325202 : if (start + min_len > eb->len) {
5128 0 : WARN(1, KERN_ERR "btrfs bad mapping eb start %llu len %lu, "
5129 : "wanted %lu %lu\n",
5130 : eb->start, eb->len, start, min_len);
5131 0 : return -EINVAL;
5132 : }
5133 :
5134 : p = extent_buffer_page(eb, i);
5135 : kaddr = page_address(p);
5136 41325202 : *map = kaddr + offset;
5137 41325202 : *map_len = PAGE_CACHE_SIZE - offset;
5138 41325202 : return 0;
5139 : }
5140 :
5141 228578 : int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv,
5142 : unsigned long start,
5143 : unsigned long len)
5144 : {
5145 : size_t cur;
5146 : size_t offset;
5147 : struct page *page;
5148 : char *kaddr;
5149 : char *ptr = (char *)ptrv;
5150 228578 : size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1);
5151 228578 : unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT;
5152 : int ret = 0;
5153 :
5154 228578 : WARN_ON(start > eb->len);
5155 228578 : WARN_ON(start + len > eb->start + eb->len);
5156 :
5157 228578 : offset = (start_offset + start) & (PAGE_CACHE_SIZE - 1);
5158 :
5159 492219 : while (len > 0) {
5160 : page = extent_buffer_page(eb, i);
5161 :
5162 229177 : cur = min(len, (PAGE_CACHE_SIZE - offset));
5163 :
5164 : kaddr = page_address(page);
5165 229177 : ret = memcmp(ptr, kaddr + offset, cur);
5166 229177 : if (ret)
5167 : break;
5168 :
5169 35063 : ptr += cur;
5170 35063 : len -= cur;
5171 : offset = 0;
5172 35063 : i++;
5173 : }
5174 228578 : return ret;
5175 : }
5176 :
5177 897735 : void write_extent_buffer(struct extent_buffer *eb, const void *srcv,
5178 : unsigned long start, unsigned long len)
5179 : {
5180 : size_t cur;
5181 : size_t offset;
5182 : struct page *page;
5183 : char *kaddr;
5184 : char *src = (char *)srcv;
5185 897735 : size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1);
5186 897735 : unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT;
5187 :
5188 897735 : WARN_ON(start > eb->len);
5189 897739 : WARN_ON(start + len > eb->start + eb->len);
5190 :
5191 897739 : offset = (start_offset + start) & (PAGE_CACHE_SIZE - 1);
5192 :
5193 2784773 : while (len > 0) {
5194 : page = extent_buffer_page(eb, i);
5195 989295 : WARN_ON(!PageUptodate(page));
5196 :
5197 989295 : cur = min(len, PAGE_CACHE_SIZE - offset);
5198 : kaddr = page_address(page);
5199 989295 : memcpy(kaddr + offset, src, cur);
5200 :
5201 989295 : src += cur;
5202 989295 : len -= cur;
5203 : offset = 0;
5204 989295 : i++;
5205 : }
5206 897746 : }
5207 :
5208 28122 : void memset_extent_buffer(struct extent_buffer *eb, char c,
5209 : unsigned long start, unsigned long len)
5210 : {
5211 : size_t cur;
5212 : size_t offset;
5213 : struct page *page;
5214 : char *kaddr;
5215 28122 : size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1);
5216 28122 : unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT;
5217 :
5218 28122 : WARN_ON(start > eb->len);
5219 28122 : WARN_ON(start + len > eb->start + eb->len);
5220 :
5221 28122 : offset = (start_offset + start) & (PAGE_CACHE_SIZE - 1);
5222 :
5223 85086 : while (len > 0) {
5224 : page = extent_buffer_page(eb, i);
5225 28842 : WARN_ON(!PageUptodate(page));
5226 :
5227 28842 : cur = min(len, PAGE_CACHE_SIZE - offset);
5228 : kaddr = page_address(page);
5229 28842 : memset(kaddr + offset, c, cur);
5230 :
5231 28842 : len -= cur;
5232 : offset = 0;
5233 28842 : i++;
5234 : }
5235 28122 : }
5236 :
5237 93062 : void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,
5238 : unsigned long dst_offset, unsigned long src_offset,
5239 : unsigned long len)
5240 : {
5241 93062 : u64 dst_len = dst->len;
5242 : size_t cur;
5243 : size_t offset;
5244 : struct page *page;
5245 : char *kaddr;
5246 93062 : size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1);
5247 93062 : unsigned long i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT;
5248 :
5249 93062 : WARN_ON(src->len != dst_len);
5250 :
5251 93061 : offset = (start_offset + dst_offset) &
5252 : (PAGE_CACHE_SIZE - 1);
5253 :
5254 400049 : while (len > 0) {
5255 : page = extent_buffer_page(dst, i);
5256 213927 : WARN_ON(!PageUptodate(page));
5257 :
5258 213927 : cur = min(len, (unsigned long)(PAGE_CACHE_SIZE - offset));
5259 :
5260 : kaddr = page_address(page);
5261 213927 : read_extent_buffer(src, kaddr + offset, src_offset, cur);
5262 :
5263 213927 : src_offset += cur;
5264 213927 : len -= cur;
5265 : offset = 0;
5266 213927 : i++;
5267 : }
5268 93064 : }
5269 :
5270 : static inline bool areas_overlap(unsigned long src, unsigned long dst, unsigned long len)
5271 : {
5272 1100198 : unsigned long distance = (src > dst) ? src - dst : dst - src;
5273 : return distance < len;
5274 : }
5275 :
5276 1476644 : static void copy_pages(struct page *dst_page, struct page *src_page,
5277 : unsigned long dst_off, unsigned long src_off,
5278 : unsigned long len)
5279 : {
5280 : char *dst_kaddr = page_address(dst_page);
5281 : char *src_kaddr;
5282 : int must_memmove = 0;
5283 :
5284 1476644 : if (dst_page != src_page) {
5285 : src_kaddr = page_address(src_page);
5286 : } else {
5287 : src_kaddr = dst_kaddr;
5288 1100198 : if (areas_overlap(src_off, dst_off, len))
5289 : must_memmove = 1;
5290 : }
5291 :
5292 1476644 : if (must_memmove)
5293 1039557 : memmove(dst_kaddr + dst_off, src_kaddr + src_off, len);
5294 : else
5295 437087 : memcpy(dst_kaddr + dst_off, src_kaddr + src_off, len);
5296 1476644 : }
5297 :
5298 410701 : void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
5299 : unsigned long src_offset, unsigned long len)
5300 : {
5301 : size_t cur;
5302 : size_t dst_off_in_page;
5303 : size_t src_off_in_page;
5304 410701 : size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1);
5305 : unsigned long dst_i;
5306 : unsigned long src_i;
5307 :
5308 410701 : if (src_offset + len > dst->len) {
5309 0 : printk(KERN_ERR "BTRFS: memmove bogus src_offset %lu move "
5310 : "len %lu dst len %lu\n", src_offset, len, dst->len);
5311 0 : BUG_ON(1);
5312 : }
5313 410701 : if (dst_offset + len > dst->len) {
5314 0 : printk(KERN_ERR "BTRFS: memmove bogus dst_offset %lu move "
5315 : "len %lu dst len %lu\n", dst_offset, len, dst->len);
5316 0 : BUG_ON(1);
5317 : }
5318 :
5319 1279924 : while (len > 0) {
5320 869240 : dst_off_in_page = (start_offset + dst_offset) &
5321 : (PAGE_CACHE_SIZE - 1);
5322 869240 : src_off_in_page = (start_offset + src_offset) &
5323 : (PAGE_CACHE_SIZE - 1);
5324 :
5325 869240 : dst_i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT;
5326 869240 : src_i = (start_offset + src_offset) >> PAGE_CACHE_SHIFT;
5327 :
5328 869240 : cur = min(len, (unsigned long)(PAGE_CACHE_SIZE -
5329 : src_off_in_page));
5330 869240 : cur = min_t(unsigned long, cur,
5331 : (unsigned long)(PAGE_CACHE_SIZE - dst_off_in_page));
5332 :
5333 869240 : copy_pages(extent_buffer_page(dst, dst_i),
5334 : extent_buffer_page(dst, src_i),
5335 : dst_off_in_page, src_off_in_page, cur);
5336 :
5337 869223 : src_offset += cur;
5338 869223 : dst_offset += cur;
5339 869223 : len -= cur;
5340 : }
5341 410684 : }
5342 :
5343 743372 : void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
5344 : unsigned long src_offset, unsigned long len)
5345 : {
5346 : size_t cur;
5347 : size_t dst_off_in_page;
5348 : size_t src_off_in_page;
5349 743372 : unsigned long dst_end = dst_offset + len - 1;
5350 743372 : unsigned long src_end = src_offset + len - 1;
5351 743372 : size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1);
5352 : unsigned long dst_i;
5353 : unsigned long src_i;
5354 :
5355 743372 : if (src_offset + len > dst->len) {
5356 0 : printk(KERN_ERR "BTRFS: memmove bogus src_offset %lu move "
5357 : "len %lu len %lu\n", src_offset, len, dst->len);
5358 0 : BUG_ON(1);
5359 : }
5360 743372 : if (dst_offset + len > dst->len) {
5361 0 : printk(KERN_ERR "BTRFS: memmove bogus dst_offset %lu move "
5362 : "len %lu len %lu\n", dst_offset, len, dst->len);
5363 0 : BUG_ON(1);
5364 : }
5365 743372 : if (dst_offset < src_offset) {
5366 408650 : memcpy_extent_buffer(dst, dst_offset, src_offset, len);
5367 1151959 : return;
5368 : }
5369 942145 : while (len > 0) {
5370 607424 : dst_i = (start_offset + dst_end) >> PAGE_CACHE_SHIFT;
5371 607424 : src_i = (start_offset + src_end) >> PAGE_CACHE_SHIFT;
5372 :
5373 607424 : dst_off_in_page = (start_offset + dst_end) &
5374 : (PAGE_CACHE_SIZE - 1);
5375 607424 : src_off_in_page = (start_offset + src_end) &
5376 : (PAGE_CACHE_SIZE - 1);
5377 :
5378 607424 : cur = min_t(unsigned long, len, src_off_in_page + 1);
5379 607424 : cur = min(cur, dst_off_in_page + 1);
5380 1822272 : copy_pages(extent_buffer_page(dst, dst_i),
5381 : extent_buffer_page(dst, src_i),
5382 607424 : dst_off_in_page - cur + 1,
5383 607424 : src_off_in_page - cur + 1, cur);
5384 :
5385 607423 : dst_end -= cur;
5386 607423 : src_end -= cur;
5387 607423 : len -= cur;
5388 : }
5389 : }
5390 :
5391 13164 : int try_release_extent_buffer(struct page *page)
5392 : {
5393 : struct extent_buffer *eb;
5394 :
5395 : /*
5396 : * We need to make sure noboody is attaching this page to an eb right
5397 : * now.
5398 : */
5399 13164 : spin_lock(&page->mapping->private_lock);
5400 13164 : if (!PagePrivate(page)) {
5401 0 : spin_unlock(&page->mapping->private_lock);
5402 0 : return 1;
5403 : }
5404 :
5405 13164 : eb = (struct extent_buffer *)page->private;
5406 13164 : BUG_ON(!eb);
5407 :
5408 : /*
5409 : * This is a little awful but should be ok, we need to make sure that
5410 : * the eb doesn't disappear out from under us while we're looking at
5411 : * this page.
5412 : */
5413 : spin_lock(&eb->refs_lock);
5414 21120 : if (atomic_read(&eb->refs) != 1 || extent_buffer_under_io(eb)) {
5415 : spin_unlock(&eb->refs_lock);
5416 5208 : spin_unlock(&page->mapping->private_lock);
5417 5208 : return 0;
5418 : }
5419 7956 : spin_unlock(&page->mapping->private_lock);
5420 :
5421 : /*
5422 : * If tree ref isn't set then we know the ref on this eb is a real ref,
5423 : * so just return, this page will likely be freed soon anyway.
5424 : */
5425 15912 : if (!test_and_clear_bit(EXTENT_BUFFER_TREE_REF, &eb->bflags)) {
5426 : spin_unlock(&eb->refs_lock);
5427 0 : return 0;
5428 : }
5429 :
5430 7956 : return release_extent_buffer(eb);
5431 : }
|
