Commit | Line | Data |
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d1310b2e CM |
1 | #include <linux/bitops.h> |
2 | #include <linux/slab.h> | |
3 | #include <linux/bio.h> | |
4 | #include <linux/mm.h> | |
5 | #include <linux/gfp.h> | |
6 | #include <linux/pagemap.h> | |
7 | #include <linux/page-flags.h> | |
8 | #include <linux/module.h> | |
9 | #include <linux/spinlock.h> | |
10 | #include <linux/blkdev.h> | |
11 | #include <linux/swap.h> | |
12 | #include <linux/version.h> | |
13 | #include <linux/writeback.h> | |
14 | #include <linux/pagevec.h> | |
15 | #include "extent_io.h" | |
16 | #include "extent_map.h" | |
2db04966 | 17 | #include "compat.h" |
902b22f3 DW |
18 | #include "ctree.h" |
19 | #include "btrfs_inode.h" | |
d1310b2e CM |
20 | |
21 | /* temporary define until extent_map moves out of btrfs */ | |
22 | struct kmem_cache *btrfs_cache_create(const char *name, size_t size, | |
23 | unsigned long extra_flags, | |
24 | void (*ctor)(void *, struct kmem_cache *, | |
25 | unsigned long)); | |
26 | ||
27 | static struct kmem_cache *extent_state_cache; | |
28 | static struct kmem_cache *extent_buffer_cache; | |
29 | ||
30 | static LIST_HEAD(buffers); | |
31 | static LIST_HEAD(states); | |
4bef0848 | 32 | |
b47eda86 | 33 | #define LEAK_DEBUG 0 |
4bef0848 | 34 | #ifdef LEAK_DEBUG |
2d2ae547 | 35 | static spinlock_t leak_lock = SPIN_LOCK_UNLOCKED; |
4bef0848 | 36 | #endif |
d1310b2e | 37 | |
d1310b2e CM |
38 | #define BUFFER_LRU_MAX 64 |
39 | ||
40 | struct tree_entry { | |
41 | u64 start; | |
42 | u64 end; | |
d1310b2e CM |
43 | struct rb_node rb_node; |
44 | }; | |
45 | ||
46 | struct extent_page_data { | |
47 | struct bio *bio; | |
48 | struct extent_io_tree *tree; | |
49 | get_extent_t *get_extent; | |
771ed689 CM |
50 | |
51 | /* tells writepage not to lock the state bits for this range | |
52 | * it still does the unlocking | |
53 | */ | |
54 | int extent_locked; | |
d1310b2e CM |
55 | }; |
56 | ||
57 | int __init extent_io_init(void) | |
58 | { | |
59 | extent_state_cache = btrfs_cache_create("extent_state", | |
60 | sizeof(struct extent_state), 0, | |
61 | NULL); | |
62 | if (!extent_state_cache) | |
63 | return -ENOMEM; | |
64 | ||
65 | extent_buffer_cache = btrfs_cache_create("extent_buffers", | |
66 | sizeof(struct extent_buffer), 0, | |
67 | NULL); | |
68 | if (!extent_buffer_cache) | |
69 | goto free_state_cache; | |
70 | return 0; | |
71 | ||
72 | free_state_cache: | |
73 | kmem_cache_destroy(extent_state_cache); | |
74 | return -ENOMEM; | |
75 | } | |
76 | ||
77 | void extent_io_exit(void) | |
78 | { | |
79 | struct extent_state *state; | |
2d2ae547 | 80 | struct extent_buffer *eb; |
d1310b2e CM |
81 | |
82 | while (!list_empty(&states)) { | |
2d2ae547 | 83 | state = list_entry(states.next, struct extent_state, leak_list); |
70dec807 | 84 | printk("state leak: start %Lu end %Lu state %lu in tree %p refs %d\n", state->start, state->end, state->state, state->tree, atomic_read(&state->refs)); |
2d2ae547 | 85 | list_del(&state->leak_list); |
d1310b2e CM |
86 | kmem_cache_free(extent_state_cache, state); |
87 | ||
88 | } | |
89 | ||
2d2ae547 CM |
90 | while (!list_empty(&buffers)) { |
91 | eb = list_entry(buffers.next, struct extent_buffer, leak_list); | |
92 | printk("buffer leak start %Lu len %lu refs %d\n", eb->start, eb->len, atomic_read(&eb->refs)); | |
93 | list_del(&eb->leak_list); | |
94 | kmem_cache_free(extent_buffer_cache, eb); | |
95 | } | |
d1310b2e CM |
96 | if (extent_state_cache) |
97 | kmem_cache_destroy(extent_state_cache); | |
98 | if (extent_buffer_cache) | |
99 | kmem_cache_destroy(extent_buffer_cache); | |
100 | } | |
101 | ||
102 | void extent_io_tree_init(struct extent_io_tree *tree, | |
103 | struct address_space *mapping, gfp_t mask) | |
104 | { | |
105 | tree->state.rb_node = NULL; | |
6af118ce | 106 | tree->buffer.rb_node = NULL; |
d1310b2e CM |
107 | tree->ops = NULL; |
108 | tree->dirty_bytes = 0; | |
70dec807 | 109 | spin_lock_init(&tree->lock); |
6af118ce | 110 | spin_lock_init(&tree->buffer_lock); |
d1310b2e | 111 | tree->mapping = mapping; |
d1310b2e CM |
112 | } |
113 | EXPORT_SYMBOL(extent_io_tree_init); | |
114 | ||
b2950863 | 115 | static struct extent_state *alloc_extent_state(gfp_t mask) |
d1310b2e CM |
116 | { |
117 | struct extent_state *state; | |
4bef0848 | 118 | #ifdef LEAK_DEBUG |
2d2ae547 | 119 | unsigned long flags; |
4bef0848 | 120 | #endif |
d1310b2e CM |
121 | |
122 | state = kmem_cache_alloc(extent_state_cache, mask); | |
2b114d1d | 123 | if (!state) |
d1310b2e CM |
124 | return state; |
125 | state->state = 0; | |
d1310b2e | 126 | state->private = 0; |
70dec807 | 127 | state->tree = NULL; |
4bef0848 | 128 | #ifdef LEAK_DEBUG |
2d2ae547 CM |
129 | spin_lock_irqsave(&leak_lock, flags); |
130 | list_add(&state->leak_list, &states); | |
131 | spin_unlock_irqrestore(&leak_lock, flags); | |
4bef0848 | 132 | #endif |
d1310b2e CM |
133 | atomic_set(&state->refs, 1); |
134 | init_waitqueue_head(&state->wq); | |
135 | return state; | |
136 | } | |
137 | EXPORT_SYMBOL(alloc_extent_state); | |
138 | ||
b2950863 | 139 | static void free_extent_state(struct extent_state *state) |
d1310b2e | 140 | { |
d1310b2e CM |
141 | if (!state) |
142 | return; | |
143 | if (atomic_dec_and_test(&state->refs)) { | |
4bef0848 | 144 | #ifdef LEAK_DEBUG |
2d2ae547 | 145 | unsigned long flags; |
4bef0848 | 146 | #endif |
70dec807 | 147 | WARN_ON(state->tree); |
4bef0848 | 148 | #ifdef LEAK_DEBUG |
2d2ae547 CM |
149 | spin_lock_irqsave(&leak_lock, flags); |
150 | list_del(&state->leak_list); | |
151 | spin_unlock_irqrestore(&leak_lock, flags); | |
4bef0848 | 152 | #endif |
d1310b2e CM |
153 | kmem_cache_free(extent_state_cache, state); |
154 | } | |
155 | } | |
156 | EXPORT_SYMBOL(free_extent_state); | |
157 | ||
158 | static struct rb_node *tree_insert(struct rb_root *root, u64 offset, | |
159 | struct rb_node *node) | |
160 | { | |
161 | struct rb_node ** p = &root->rb_node; | |
162 | struct rb_node * parent = NULL; | |
163 | struct tree_entry *entry; | |
164 | ||
165 | while(*p) { | |
166 | parent = *p; | |
167 | entry = rb_entry(parent, struct tree_entry, rb_node); | |
168 | ||
169 | if (offset < entry->start) | |
170 | p = &(*p)->rb_left; | |
171 | else if (offset > entry->end) | |
172 | p = &(*p)->rb_right; | |
173 | else | |
174 | return parent; | |
175 | } | |
176 | ||
177 | entry = rb_entry(node, struct tree_entry, rb_node); | |
d1310b2e CM |
178 | rb_link_node(node, parent, p); |
179 | rb_insert_color(node, root); | |
180 | return NULL; | |
181 | } | |
182 | ||
80ea96b1 | 183 | static struct rb_node *__etree_search(struct extent_io_tree *tree, u64 offset, |
d1310b2e CM |
184 | struct rb_node **prev_ret, |
185 | struct rb_node **next_ret) | |
186 | { | |
80ea96b1 | 187 | struct rb_root *root = &tree->state; |
d1310b2e CM |
188 | struct rb_node * n = root->rb_node; |
189 | struct rb_node *prev = NULL; | |
190 | struct rb_node *orig_prev = NULL; | |
191 | struct tree_entry *entry; | |
192 | struct tree_entry *prev_entry = NULL; | |
193 | ||
194 | while(n) { | |
195 | entry = rb_entry(n, struct tree_entry, rb_node); | |
196 | prev = n; | |
197 | prev_entry = entry; | |
198 | ||
199 | if (offset < entry->start) | |
200 | n = n->rb_left; | |
201 | else if (offset > entry->end) | |
202 | n = n->rb_right; | |
80ea96b1 | 203 | else { |
d1310b2e | 204 | return n; |
80ea96b1 | 205 | } |
d1310b2e CM |
206 | } |
207 | ||
208 | if (prev_ret) { | |
209 | orig_prev = prev; | |
210 | while(prev && offset > prev_entry->end) { | |
211 | prev = rb_next(prev); | |
212 | prev_entry = rb_entry(prev, struct tree_entry, rb_node); | |
213 | } | |
214 | *prev_ret = prev; | |
215 | prev = orig_prev; | |
216 | } | |
217 | ||
218 | if (next_ret) { | |
219 | prev_entry = rb_entry(prev, struct tree_entry, rb_node); | |
220 | while(prev && offset < prev_entry->start) { | |
221 | prev = rb_prev(prev); | |
222 | prev_entry = rb_entry(prev, struct tree_entry, rb_node); | |
223 | } | |
224 | *next_ret = prev; | |
225 | } | |
226 | return NULL; | |
227 | } | |
228 | ||
80ea96b1 CM |
229 | static inline struct rb_node *tree_search(struct extent_io_tree *tree, |
230 | u64 offset) | |
d1310b2e | 231 | { |
70dec807 | 232 | struct rb_node *prev = NULL; |
d1310b2e | 233 | struct rb_node *ret; |
70dec807 | 234 | |
80ea96b1 CM |
235 | ret = __etree_search(tree, offset, &prev, NULL); |
236 | if (!ret) { | |
d1310b2e | 237 | return prev; |
80ea96b1 | 238 | } |
d1310b2e CM |
239 | return ret; |
240 | } | |
241 | ||
6af118ce CM |
242 | static struct extent_buffer *buffer_tree_insert(struct extent_io_tree *tree, |
243 | u64 offset, struct rb_node *node) | |
244 | { | |
245 | struct rb_root *root = &tree->buffer; | |
246 | struct rb_node ** p = &root->rb_node; | |
247 | struct rb_node * parent = NULL; | |
248 | struct extent_buffer *eb; | |
249 | ||
250 | while(*p) { | |
251 | parent = *p; | |
252 | eb = rb_entry(parent, struct extent_buffer, rb_node); | |
253 | ||
254 | if (offset < eb->start) | |
255 | p = &(*p)->rb_left; | |
256 | else if (offset > eb->start) | |
257 | p = &(*p)->rb_right; | |
258 | else | |
259 | return eb; | |
260 | } | |
261 | ||
262 | rb_link_node(node, parent, p); | |
263 | rb_insert_color(node, root); | |
264 | return NULL; | |
265 | } | |
266 | ||
267 | static struct extent_buffer *buffer_search(struct extent_io_tree *tree, | |
268 | u64 offset) | |
269 | { | |
270 | struct rb_root *root = &tree->buffer; | |
271 | struct rb_node * n = root->rb_node; | |
272 | struct extent_buffer *eb; | |
273 | ||
274 | while(n) { | |
275 | eb = rb_entry(n, struct extent_buffer, rb_node); | |
276 | if (offset < eb->start) | |
277 | n = n->rb_left; | |
278 | else if (offset > eb->start) | |
279 | n = n->rb_right; | |
280 | else | |
281 | return eb; | |
282 | } | |
283 | return NULL; | |
284 | } | |
285 | ||
d1310b2e CM |
286 | /* |
287 | * utility function to look for merge candidates inside a given range. | |
288 | * Any extents with matching state are merged together into a single | |
289 | * extent in the tree. Extents with EXTENT_IO in their state field | |
290 | * are not merged because the end_io handlers need to be able to do | |
291 | * operations on them without sleeping (or doing allocations/splits). | |
292 | * | |
293 | * This should be called with the tree lock held. | |
294 | */ | |
295 | static int merge_state(struct extent_io_tree *tree, | |
296 | struct extent_state *state) | |
297 | { | |
298 | struct extent_state *other; | |
299 | struct rb_node *other_node; | |
300 | ||
5b21f2ed | 301 | if (state->state & (EXTENT_IOBITS | EXTENT_BOUNDARY)) |
d1310b2e CM |
302 | return 0; |
303 | ||
304 | other_node = rb_prev(&state->rb_node); | |
305 | if (other_node) { | |
306 | other = rb_entry(other_node, struct extent_state, rb_node); | |
307 | if (other->end == state->start - 1 && | |
308 | other->state == state->state) { | |
309 | state->start = other->start; | |
70dec807 | 310 | other->tree = NULL; |
d1310b2e CM |
311 | rb_erase(&other->rb_node, &tree->state); |
312 | free_extent_state(other); | |
313 | } | |
314 | } | |
315 | other_node = rb_next(&state->rb_node); | |
316 | if (other_node) { | |
317 | other = rb_entry(other_node, struct extent_state, rb_node); | |
318 | if (other->start == state->end + 1 && | |
319 | other->state == state->state) { | |
320 | other->start = state->start; | |
70dec807 | 321 | state->tree = NULL; |
d1310b2e CM |
322 | rb_erase(&state->rb_node, &tree->state); |
323 | free_extent_state(state); | |
324 | } | |
325 | } | |
326 | return 0; | |
327 | } | |
328 | ||
291d673e CM |
329 | static void set_state_cb(struct extent_io_tree *tree, |
330 | struct extent_state *state, | |
331 | unsigned long bits) | |
332 | { | |
333 | if (tree->ops && tree->ops->set_bit_hook) { | |
334 | tree->ops->set_bit_hook(tree->mapping->host, state->start, | |
b0c68f8b | 335 | state->end, state->state, bits); |
291d673e CM |
336 | } |
337 | } | |
338 | ||
339 | static void clear_state_cb(struct extent_io_tree *tree, | |
340 | struct extent_state *state, | |
341 | unsigned long bits) | |
342 | { | |
343 | if (tree->ops && tree->ops->set_bit_hook) { | |
344 | tree->ops->clear_bit_hook(tree->mapping->host, state->start, | |
b0c68f8b | 345 | state->end, state->state, bits); |
291d673e CM |
346 | } |
347 | } | |
348 | ||
d1310b2e CM |
349 | /* |
350 | * insert an extent_state struct into the tree. 'bits' are set on the | |
351 | * struct before it is inserted. | |
352 | * | |
353 | * This may return -EEXIST if the extent is already there, in which case the | |
354 | * state struct is freed. | |
355 | * | |
356 | * The tree lock is not taken internally. This is a utility function and | |
357 | * probably isn't what you want to call (see set/clear_extent_bit). | |
358 | */ | |
359 | static int insert_state(struct extent_io_tree *tree, | |
360 | struct extent_state *state, u64 start, u64 end, | |
361 | int bits) | |
362 | { | |
363 | struct rb_node *node; | |
364 | ||
365 | if (end < start) { | |
366 | printk("end < start %Lu %Lu\n", end, start); | |
367 | WARN_ON(1); | |
368 | } | |
369 | if (bits & EXTENT_DIRTY) | |
370 | tree->dirty_bytes += end - start + 1; | |
b0c68f8b | 371 | set_state_cb(tree, state, bits); |
d1310b2e CM |
372 | state->state |= bits; |
373 | state->start = start; | |
374 | state->end = end; | |
375 | node = tree_insert(&tree->state, end, &state->rb_node); | |
376 | if (node) { | |
377 | struct extent_state *found; | |
378 | found = rb_entry(node, struct extent_state, rb_node); | |
379 | printk("found node %Lu %Lu on insert of %Lu %Lu\n", found->start, found->end, start, end); | |
380 | free_extent_state(state); | |
381 | return -EEXIST; | |
382 | } | |
70dec807 | 383 | state->tree = tree; |
d1310b2e CM |
384 | merge_state(tree, state); |
385 | return 0; | |
386 | } | |
387 | ||
388 | /* | |
389 | * split a given extent state struct in two, inserting the preallocated | |
390 | * struct 'prealloc' as the newly created second half. 'split' indicates an | |
391 | * offset inside 'orig' where it should be split. | |
392 | * | |
393 | * Before calling, | |
394 | * the tree has 'orig' at [orig->start, orig->end]. After calling, there | |
395 | * are two extent state structs in the tree: | |
396 | * prealloc: [orig->start, split - 1] | |
397 | * orig: [ split, orig->end ] | |
398 | * | |
399 | * The tree locks are not taken by this function. They need to be held | |
400 | * by the caller. | |
401 | */ | |
402 | static int split_state(struct extent_io_tree *tree, struct extent_state *orig, | |
403 | struct extent_state *prealloc, u64 split) | |
404 | { | |
405 | struct rb_node *node; | |
406 | prealloc->start = orig->start; | |
407 | prealloc->end = split - 1; | |
408 | prealloc->state = orig->state; | |
409 | orig->start = split; | |
410 | ||
411 | node = tree_insert(&tree->state, prealloc->end, &prealloc->rb_node); | |
412 | if (node) { | |
413 | struct extent_state *found; | |
414 | found = rb_entry(node, struct extent_state, rb_node); | |
415 | printk("found node %Lu %Lu on insert of %Lu %Lu\n", found->start, found->end, prealloc->start, prealloc->end); | |
416 | free_extent_state(prealloc); | |
417 | return -EEXIST; | |
418 | } | |
70dec807 | 419 | prealloc->tree = tree; |
d1310b2e CM |
420 | return 0; |
421 | } | |
422 | ||
423 | /* | |
424 | * utility function to clear some bits in an extent state struct. | |
425 | * it will optionally wake up any one waiting on this state (wake == 1), or | |
426 | * forcibly remove the state from the tree (delete == 1). | |
427 | * | |
428 | * If no bits are set on the state struct after clearing things, the | |
429 | * struct is freed and removed from the tree | |
430 | */ | |
431 | static int clear_state_bit(struct extent_io_tree *tree, | |
432 | struct extent_state *state, int bits, int wake, | |
433 | int delete) | |
434 | { | |
435 | int ret = state->state & bits; | |
436 | ||
437 | if ((bits & EXTENT_DIRTY) && (state->state & EXTENT_DIRTY)) { | |
438 | u64 range = state->end - state->start + 1; | |
439 | WARN_ON(range > tree->dirty_bytes); | |
440 | tree->dirty_bytes -= range; | |
441 | } | |
291d673e | 442 | clear_state_cb(tree, state, bits); |
b0c68f8b | 443 | state->state &= ~bits; |
d1310b2e CM |
444 | if (wake) |
445 | wake_up(&state->wq); | |
446 | if (delete || state->state == 0) { | |
70dec807 | 447 | if (state->tree) { |
ae9d1285 | 448 | clear_state_cb(tree, state, state->state); |
d1310b2e | 449 | rb_erase(&state->rb_node, &tree->state); |
70dec807 | 450 | state->tree = NULL; |
d1310b2e CM |
451 | free_extent_state(state); |
452 | } else { | |
453 | WARN_ON(1); | |
454 | } | |
455 | } else { | |
456 | merge_state(tree, state); | |
457 | } | |
458 | return ret; | |
459 | } | |
460 | ||
461 | /* | |
462 | * clear some bits on a range in the tree. This may require splitting | |
463 | * or inserting elements in the tree, so the gfp mask is used to | |
464 | * indicate which allocations or sleeping are allowed. | |
465 | * | |
466 | * pass 'wake' == 1 to kick any sleepers, and 'delete' == 1 to remove | |
467 | * the given range from the tree regardless of state (ie for truncate). | |
468 | * | |
469 | * the range [start, end] is inclusive. | |
470 | * | |
471 | * This takes the tree lock, and returns < 0 on error, > 0 if any of the | |
472 | * bits were already set, or zero if none of the bits were already set. | |
473 | */ | |
474 | int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, | |
475 | int bits, int wake, int delete, gfp_t mask) | |
476 | { | |
477 | struct extent_state *state; | |
478 | struct extent_state *prealloc = NULL; | |
479 | struct rb_node *node; | |
480 | unsigned long flags; | |
481 | int err; | |
482 | int set = 0; | |
483 | ||
484 | again: | |
485 | if (!prealloc && (mask & __GFP_WAIT)) { | |
486 | prealloc = alloc_extent_state(mask); | |
487 | if (!prealloc) | |
488 | return -ENOMEM; | |
489 | } | |
490 | ||
70dec807 | 491 | spin_lock_irqsave(&tree->lock, flags); |
d1310b2e CM |
492 | /* |
493 | * this search will find the extents that end after | |
494 | * our range starts | |
495 | */ | |
80ea96b1 | 496 | node = tree_search(tree, start); |
d1310b2e CM |
497 | if (!node) |
498 | goto out; | |
499 | state = rb_entry(node, struct extent_state, rb_node); | |
500 | if (state->start > end) | |
501 | goto out; | |
502 | WARN_ON(state->end < start); | |
503 | ||
504 | /* | |
505 | * | ---- desired range ---- | | |
506 | * | state | or | |
507 | * | ------------- state -------------- | | |
508 | * | |
509 | * We need to split the extent we found, and may flip | |
510 | * bits on second half. | |
511 | * | |
512 | * If the extent we found extends past our range, we | |
513 | * just split and search again. It'll get split again | |
514 | * the next time though. | |
515 | * | |
516 | * If the extent we found is inside our range, we clear | |
517 | * the desired bit on it. | |
518 | */ | |
519 | ||
520 | if (state->start < start) { | |
70dec807 CM |
521 | if (!prealloc) |
522 | prealloc = alloc_extent_state(GFP_ATOMIC); | |
d1310b2e CM |
523 | err = split_state(tree, state, prealloc, start); |
524 | BUG_ON(err == -EEXIST); | |
525 | prealloc = NULL; | |
526 | if (err) | |
527 | goto out; | |
528 | if (state->end <= end) { | |
529 | start = state->end + 1; | |
530 | set |= clear_state_bit(tree, state, bits, | |
531 | wake, delete); | |
532 | } else { | |
533 | start = state->start; | |
534 | } | |
535 | goto search_again; | |
536 | } | |
537 | /* | |
538 | * | ---- desired range ---- | | |
539 | * | state | | |
540 | * We need to split the extent, and clear the bit | |
541 | * on the first half | |
542 | */ | |
543 | if (state->start <= end && state->end > end) { | |
70dec807 CM |
544 | if (!prealloc) |
545 | prealloc = alloc_extent_state(GFP_ATOMIC); | |
d1310b2e CM |
546 | err = split_state(tree, state, prealloc, end + 1); |
547 | BUG_ON(err == -EEXIST); | |
548 | ||
549 | if (wake) | |
550 | wake_up(&state->wq); | |
551 | set |= clear_state_bit(tree, prealloc, bits, | |
552 | wake, delete); | |
553 | prealloc = NULL; | |
554 | goto out; | |
555 | } | |
556 | ||
557 | start = state->end + 1; | |
558 | set |= clear_state_bit(tree, state, bits, wake, delete); | |
559 | goto search_again; | |
560 | ||
561 | out: | |
70dec807 | 562 | spin_unlock_irqrestore(&tree->lock, flags); |
d1310b2e CM |
563 | if (prealloc) |
564 | free_extent_state(prealloc); | |
565 | ||
566 | return set; | |
567 | ||
568 | search_again: | |
569 | if (start > end) | |
570 | goto out; | |
70dec807 | 571 | spin_unlock_irqrestore(&tree->lock, flags); |
d1310b2e CM |
572 | if (mask & __GFP_WAIT) |
573 | cond_resched(); | |
574 | goto again; | |
575 | } | |
576 | EXPORT_SYMBOL(clear_extent_bit); | |
577 | ||
578 | static int wait_on_state(struct extent_io_tree *tree, | |
579 | struct extent_state *state) | |
641f5219 CH |
580 | __releases(tree->lock) |
581 | __acquires(tree->lock) | |
d1310b2e CM |
582 | { |
583 | DEFINE_WAIT(wait); | |
584 | prepare_to_wait(&state->wq, &wait, TASK_UNINTERRUPTIBLE); | |
70dec807 | 585 | spin_unlock_irq(&tree->lock); |
d1310b2e | 586 | schedule(); |
70dec807 | 587 | spin_lock_irq(&tree->lock); |
d1310b2e CM |
588 | finish_wait(&state->wq, &wait); |
589 | return 0; | |
590 | } | |
591 | ||
592 | /* | |
593 | * waits for one or more bits to clear on a range in the state tree. | |
594 | * The range [start, end] is inclusive. | |
595 | * The tree lock is taken by this function | |
596 | */ | |
597 | int wait_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, int bits) | |
598 | { | |
599 | struct extent_state *state; | |
600 | struct rb_node *node; | |
601 | ||
70dec807 | 602 | spin_lock_irq(&tree->lock); |
d1310b2e CM |
603 | again: |
604 | while (1) { | |
605 | /* | |
606 | * this search will find all the extents that end after | |
607 | * our range starts | |
608 | */ | |
80ea96b1 | 609 | node = tree_search(tree, start); |
d1310b2e CM |
610 | if (!node) |
611 | break; | |
612 | ||
613 | state = rb_entry(node, struct extent_state, rb_node); | |
614 | ||
615 | if (state->start > end) | |
616 | goto out; | |
617 | ||
618 | if (state->state & bits) { | |
619 | start = state->start; | |
620 | atomic_inc(&state->refs); | |
621 | wait_on_state(tree, state); | |
622 | free_extent_state(state); | |
623 | goto again; | |
624 | } | |
625 | start = state->end + 1; | |
626 | ||
627 | if (start > end) | |
628 | break; | |
629 | ||
630 | if (need_resched()) { | |
70dec807 | 631 | spin_unlock_irq(&tree->lock); |
d1310b2e | 632 | cond_resched(); |
70dec807 | 633 | spin_lock_irq(&tree->lock); |
d1310b2e CM |
634 | } |
635 | } | |
636 | out: | |
70dec807 | 637 | spin_unlock_irq(&tree->lock); |
d1310b2e CM |
638 | return 0; |
639 | } | |
640 | EXPORT_SYMBOL(wait_extent_bit); | |
641 | ||
642 | static void set_state_bits(struct extent_io_tree *tree, | |
643 | struct extent_state *state, | |
644 | int bits) | |
645 | { | |
646 | if ((bits & EXTENT_DIRTY) && !(state->state & EXTENT_DIRTY)) { | |
647 | u64 range = state->end - state->start + 1; | |
648 | tree->dirty_bytes += range; | |
649 | } | |
291d673e | 650 | set_state_cb(tree, state, bits); |
b0c68f8b | 651 | state->state |= bits; |
d1310b2e CM |
652 | } |
653 | ||
654 | /* | |
655 | * set some bits on a range in the tree. This may require allocations | |
656 | * or sleeping, so the gfp mask is used to indicate what is allowed. | |
657 | * | |
658 | * If 'exclusive' == 1, this will fail with -EEXIST if some part of the | |
659 | * range already has the desired bits set. The start of the existing | |
660 | * range is returned in failed_start in this case. | |
661 | * | |
662 | * [start, end] is inclusive | |
663 | * This takes the tree lock. | |
664 | */ | |
b2950863 | 665 | static int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, int bits, |
d1310b2e CM |
666 | int exclusive, u64 *failed_start, gfp_t mask) |
667 | { | |
668 | struct extent_state *state; | |
669 | struct extent_state *prealloc = NULL; | |
670 | struct rb_node *node; | |
671 | unsigned long flags; | |
672 | int err = 0; | |
673 | int set; | |
674 | u64 last_start; | |
675 | u64 last_end; | |
676 | again: | |
677 | if (!prealloc && (mask & __GFP_WAIT)) { | |
678 | prealloc = alloc_extent_state(mask); | |
679 | if (!prealloc) | |
680 | return -ENOMEM; | |
681 | } | |
682 | ||
70dec807 | 683 | spin_lock_irqsave(&tree->lock, flags); |
d1310b2e CM |
684 | /* |
685 | * this search will find all the extents that end after | |
686 | * our range starts. | |
687 | */ | |
80ea96b1 | 688 | node = tree_search(tree, start); |
d1310b2e CM |
689 | if (!node) { |
690 | err = insert_state(tree, prealloc, start, end, bits); | |
691 | prealloc = NULL; | |
692 | BUG_ON(err == -EEXIST); | |
693 | goto out; | |
694 | } | |
695 | ||
696 | state = rb_entry(node, struct extent_state, rb_node); | |
697 | last_start = state->start; | |
698 | last_end = state->end; | |
699 | ||
700 | /* | |
701 | * | ---- desired range ---- | | |
702 | * | state | | |
703 | * | |
704 | * Just lock what we found and keep going | |
705 | */ | |
706 | if (state->start == start && state->end <= end) { | |
707 | set = state->state & bits; | |
708 | if (set && exclusive) { | |
709 | *failed_start = state->start; | |
710 | err = -EEXIST; | |
711 | goto out; | |
712 | } | |
713 | set_state_bits(tree, state, bits); | |
714 | start = state->end + 1; | |
715 | merge_state(tree, state); | |
716 | goto search_again; | |
717 | } | |
718 | ||
719 | /* | |
720 | * | ---- desired range ---- | | |
721 | * | state | | |
722 | * or | |
723 | * | ------------- state -------------- | | |
724 | * | |
725 | * We need to split the extent we found, and may flip bits on | |
726 | * second half. | |
727 | * | |
728 | * If the extent we found extends past our | |
729 | * range, we just split and search again. It'll get split | |
730 | * again the next time though. | |
731 | * | |
732 | * If the extent we found is inside our range, we set the | |
733 | * desired bit on it. | |
734 | */ | |
735 | if (state->start < start) { | |
736 | set = state->state & bits; | |
737 | if (exclusive && set) { | |
738 | *failed_start = start; | |
739 | err = -EEXIST; | |
740 | goto out; | |
741 | } | |
742 | err = split_state(tree, state, prealloc, start); | |
743 | BUG_ON(err == -EEXIST); | |
744 | prealloc = NULL; | |
745 | if (err) | |
746 | goto out; | |
747 | if (state->end <= end) { | |
748 | set_state_bits(tree, state, bits); | |
749 | start = state->end + 1; | |
750 | merge_state(tree, state); | |
751 | } else { | |
752 | start = state->start; | |
753 | } | |
754 | goto search_again; | |
755 | } | |
756 | /* | |
757 | * | ---- desired range ---- | | |
758 | * | state | or | state | | |
759 | * | |
760 | * There's a hole, we need to insert something in it and | |
761 | * ignore the extent we found. | |
762 | */ | |
763 | if (state->start > start) { | |
764 | u64 this_end; | |
765 | if (end < last_start) | |
766 | this_end = end; | |
767 | else | |
768 | this_end = last_start -1; | |
769 | err = insert_state(tree, prealloc, start, this_end, | |
770 | bits); | |
771 | prealloc = NULL; | |
772 | BUG_ON(err == -EEXIST); | |
773 | if (err) | |
774 | goto out; | |
775 | start = this_end + 1; | |
776 | goto search_again; | |
777 | } | |
778 | /* | |
779 | * | ---- desired range ---- | | |
780 | * | state | | |
781 | * We need to split the extent, and set the bit | |
782 | * on the first half | |
783 | */ | |
784 | if (state->start <= end && state->end > end) { | |
785 | set = state->state & bits; | |
786 | if (exclusive && set) { | |
787 | *failed_start = start; | |
788 | err = -EEXIST; | |
789 | goto out; | |
790 | } | |
791 | err = split_state(tree, state, prealloc, end + 1); | |
792 | BUG_ON(err == -EEXIST); | |
793 | ||
794 | set_state_bits(tree, prealloc, bits); | |
795 | merge_state(tree, prealloc); | |
796 | prealloc = NULL; | |
797 | goto out; | |
798 | } | |
799 | ||
800 | goto search_again; | |
801 | ||
802 | out: | |
70dec807 | 803 | spin_unlock_irqrestore(&tree->lock, flags); |
d1310b2e CM |
804 | if (prealloc) |
805 | free_extent_state(prealloc); | |
806 | ||
807 | return err; | |
808 | ||
809 | search_again: | |
810 | if (start > end) | |
811 | goto out; | |
70dec807 | 812 | spin_unlock_irqrestore(&tree->lock, flags); |
d1310b2e CM |
813 | if (mask & __GFP_WAIT) |
814 | cond_resched(); | |
815 | goto again; | |
816 | } | |
817 | EXPORT_SYMBOL(set_extent_bit); | |
818 | ||
819 | /* wrappers around set/clear extent bit */ | |
820 | int set_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end, | |
821 | gfp_t mask) | |
822 | { | |
823 | return set_extent_bit(tree, start, end, EXTENT_DIRTY, 0, NULL, | |
824 | mask); | |
825 | } | |
826 | EXPORT_SYMBOL(set_extent_dirty); | |
827 | ||
e6dcd2dc CM |
828 | int set_extent_ordered(struct extent_io_tree *tree, u64 start, u64 end, |
829 | gfp_t mask) | |
830 | { | |
831 | return set_extent_bit(tree, start, end, EXTENT_ORDERED, 0, NULL, mask); | |
832 | } | |
833 | EXPORT_SYMBOL(set_extent_ordered); | |
834 | ||
d1310b2e CM |
835 | int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, |
836 | int bits, gfp_t mask) | |
837 | { | |
838 | return set_extent_bit(tree, start, end, bits, 0, NULL, | |
839 | mask); | |
840 | } | |
841 | EXPORT_SYMBOL(set_extent_bits); | |
842 | ||
843 | int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, | |
844 | int bits, gfp_t mask) | |
845 | { | |
846 | return clear_extent_bit(tree, start, end, bits, 0, 0, mask); | |
847 | } | |
848 | EXPORT_SYMBOL(clear_extent_bits); | |
849 | ||
850 | int set_extent_delalloc(struct extent_io_tree *tree, u64 start, u64 end, | |
851 | gfp_t mask) | |
852 | { | |
853 | return set_extent_bit(tree, start, end, | |
e6dcd2dc CM |
854 | EXTENT_DELALLOC | EXTENT_DIRTY, |
855 | 0, NULL, mask); | |
d1310b2e CM |
856 | } |
857 | EXPORT_SYMBOL(set_extent_delalloc); | |
858 | ||
859 | int clear_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end, | |
860 | gfp_t mask) | |
861 | { | |
862 | return clear_extent_bit(tree, start, end, | |
863 | EXTENT_DIRTY | EXTENT_DELALLOC, 0, 0, mask); | |
864 | } | |
865 | EXPORT_SYMBOL(clear_extent_dirty); | |
866 | ||
e6dcd2dc CM |
867 | int clear_extent_ordered(struct extent_io_tree *tree, u64 start, u64 end, |
868 | gfp_t mask) | |
869 | { | |
870 | return clear_extent_bit(tree, start, end, EXTENT_ORDERED, 1, 0, mask); | |
871 | } | |
872 | EXPORT_SYMBOL(clear_extent_ordered); | |
873 | ||
d1310b2e CM |
874 | int set_extent_new(struct extent_io_tree *tree, u64 start, u64 end, |
875 | gfp_t mask) | |
876 | { | |
877 | return set_extent_bit(tree, start, end, EXTENT_NEW, 0, NULL, | |
878 | mask); | |
879 | } | |
880 | EXPORT_SYMBOL(set_extent_new); | |
881 | ||
b2950863 | 882 | static int clear_extent_new(struct extent_io_tree *tree, u64 start, u64 end, |
d1310b2e CM |
883 | gfp_t mask) |
884 | { | |
885 | return clear_extent_bit(tree, start, end, EXTENT_NEW, 0, 0, mask); | |
886 | } | |
d1310b2e CM |
887 | |
888 | int set_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end, | |
889 | gfp_t mask) | |
890 | { | |
891 | return set_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, NULL, | |
892 | mask); | |
893 | } | |
894 | EXPORT_SYMBOL(set_extent_uptodate); | |
895 | ||
b2950863 | 896 | static int clear_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end, |
d1310b2e CM |
897 | gfp_t mask) |
898 | { | |
899 | return clear_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, 0, mask); | |
900 | } | |
d1310b2e | 901 | |
b2950863 | 902 | static int set_extent_writeback(struct extent_io_tree *tree, u64 start, u64 end, |
d1310b2e CM |
903 | gfp_t mask) |
904 | { | |
905 | return set_extent_bit(tree, start, end, EXTENT_WRITEBACK, | |
906 | 0, NULL, mask); | |
907 | } | |
d1310b2e | 908 | |
b2950863 | 909 | static int clear_extent_writeback(struct extent_io_tree *tree, u64 start, u64 end, |
d1310b2e CM |
910 | gfp_t mask) |
911 | { | |
912 | return clear_extent_bit(tree, start, end, EXTENT_WRITEBACK, 1, 0, mask); | |
913 | } | |
d1310b2e CM |
914 | |
915 | int wait_on_extent_writeback(struct extent_io_tree *tree, u64 start, u64 end) | |
916 | { | |
917 | return wait_extent_bit(tree, start, end, EXTENT_WRITEBACK); | |
918 | } | |
919 | EXPORT_SYMBOL(wait_on_extent_writeback); | |
920 | ||
d352ac68 CM |
921 | /* |
922 | * either insert or lock state struct between start and end use mask to tell | |
923 | * us if waiting is desired. | |
924 | */ | |
d1310b2e CM |
925 | int lock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask) |
926 | { | |
927 | int err; | |
928 | u64 failed_start; | |
929 | while (1) { | |
930 | err = set_extent_bit(tree, start, end, EXTENT_LOCKED, 1, | |
931 | &failed_start, mask); | |
932 | if (err == -EEXIST && (mask & __GFP_WAIT)) { | |
933 | wait_extent_bit(tree, failed_start, end, EXTENT_LOCKED); | |
934 | start = failed_start; | |
935 | } else { | |
936 | break; | |
937 | } | |
938 | WARN_ON(start > end); | |
939 | } | |
940 | return err; | |
941 | } | |
942 | EXPORT_SYMBOL(lock_extent); | |
943 | ||
25179201 JB |
944 | int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end, |
945 | gfp_t mask) | |
946 | { | |
947 | int err; | |
948 | u64 failed_start; | |
949 | ||
950 | err = set_extent_bit(tree, start, end, EXTENT_LOCKED, 1, | |
951 | &failed_start, mask); | |
6643558d YZ |
952 | if (err == -EEXIST) { |
953 | if (failed_start > start) | |
954 | clear_extent_bit(tree, start, failed_start - 1, | |
955 | EXTENT_LOCKED, 1, 0, mask); | |
25179201 | 956 | return 0; |
6643558d | 957 | } |
25179201 JB |
958 | return 1; |
959 | } | |
960 | EXPORT_SYMBOL(try_lock_extent); | |
961 | ||
d1310b2e CM |
962 | int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end, |
963 | gfp_t mask) | |
964 | { | |
965 | return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, mask); | |
966 | } | |
967 | EXPORT_SYMBOL(unlock_extent); | |
968 | ||
969 | /* | |
970 | * helper function to set pages and extents in the tree dirty | |
971 | */ | |
972 | int set_range_dirty(struct extent_io_tree *tree, u64 start, u64 end) | |
973 | { | |
974 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
975 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
976 | struct page *page; | |
977 | ||
978 | while (index <= end_index) { | |
979 | page = find_get_page(tree->mapping, index); | |
980 | BUG_ON(!page); | |
981 | __set_page_dirty_nobuffers(page); | |
982 | page_cache_release(page); | |
983 | index++; | |
984 | } | |
985 | set_extent_dirty(tree, start, end, GFP_NOFS); | |
986 | return 0; | |
987 | } | |
988 | EXPORT_SYMBOL(set_range_dirty); | |
989 | ||
990 | /* | |
991 | * helper function to set both pages and extents in the tree writeback | |
992 | */ | |
b2950863 | 993 | static int set_range_writeback(struct extent_io_tree *tree, u64 start, u64 end) |
d1310b2e CM |
994 | { |
995 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
996 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
997 | struct page *page; | |
998 | ||
999 | while (index <= end_index) { | |
1000 | page = find_get_page(tree->mapping, index); | |
1001 | BUG_ON(!page); | |
1002 | set_page_writeback(page); | |
1003 | page_cache_release(page); | |
1004 | index++; | |
1005 | } | |
1006 | set_extent_writeback(tree, start, end, GFP_NOFS); | |
1007 | return 0; | |
1008 | } | |
d1310b2e | 1009 | |
d352ac68 CM |
1010 | /* |
1011 | * find the first offset in the io tree with 'bits' set. zero is | |
1012 | * returned if we find something, and *start_ret and *end_ret are | |
1013 | * set to reflect the state struct that was found. | |
1014 | * | |
1015 | * If nothing was found, 1 is returned, < 0 on error | |
1016 | */ | |
d1310b2e CM |
1017 | int find_first_extent_bit(struct extent_io_tree *tree, u64 start, |
1018 | u64 *start_ret, u64 *end_ret, int bits) | |
1019 | { | |
1020 | struct rb_node *node; | |
1021 | struct extent_state *state; | |
1022 | int ret = 1; | |
1023 | ||
70dec807 | 1024 | spin_lock_irq(&tree->lock); |
d1310b2e CM |
1025 | /* |
1026 | * this search will find all the extents that end after | |
1027 | * our range starts. | |
1028 | */ | |
80ea96b1 | 1029 | node = tree_search(tree, start); |
2b114d1d | 1030 | if (!node) { |
d1310b2e CM |
1031 | goto out; |
1032 | } | |
1033 | ||
1034 | while(1) { | |
1035 | state = rb_entry(node, struct extent_state, rb_node); | |
1036 | if (state->end >= start && (state->state & bits)) { | |
1037 | *start_ret = state->start; | |
1038 | *end_ret = state->end; | |
1039 | ret = 0; | |
1040 | break; | |
1041 | } | |
1042 | node = rb_next(node); | |
1043 | if (!node) | |
1044 | break; | |
1045 | } | |
1046 | out: | |
70dec807 | 1047 | spin_unlock_irq(&tree->lock); |
d1310b2e CM |
1048 | return ret; |
1049 | } | |
1050 | EXPORT_SYMBOL(find_first_extent_bit); | |
1051 | ||
d352ac68 CM |
1052 | /* find the first state struct with 'bits' set after 'start', and |
1053 | * return it. tree->lock must be held. NULL will returned if | |
1054 | * nothing was found after 'start' | |
1055 | */ | |
d7fc640e CM |
1056 | struct extent_state *find_first_extent_bit_state(struct extent_io_tree *tree, |
1057 | u64 start, int bits) | |
1058 | { | |
1059 | struct rb_node *node; | |
1060 | struct extent_state *state; | |
1061 | ||
1062 | /* | |
1063 | * this search will find all the extents that end after | |
1064 | * our range starts. | |
1065 | */ | |
1066 | node = tree_search(tree, start); | |
2b114d1d | 1067 | if (!node) { |
d7fc640e CM |
1068 | goto out; |
1069 | } | |
1070 | ||
1071 | while(1) { | |
1072 | state = rb_entry(node, struct extent_state, rb_node); | |
1073 | if (state->end >= start && (state->state & bits)) { | |
1074 | return state; | |
1075 | } | |
1076 | node = rb_next(node); | |
1077 | if (!node) | |
1078 | break; | |
1079 | } | |
1080 | out: | |
1081 | return NULL; | |
1082 | } | |
1083 | EXPORT_SYMBOL(find_first_extent_bit_state); | |
1084 | ||
d352ac68 CM |
1085 | /* |
1086 | * find a contiguous range of bytes in the file marked as delalloc, not | |
1087 | * more than 'max_bytes'. start and end are used to return the range, | |
1088 | * | |
1089 | * 1 is returned if we find something, 0 if nothing was in the tree | |
1090 | */ | |
c8b97818 CM |
1091 | static noinline u64 find_delalloc_range(struct extent_io_tree *tree, |
1092 | u64 *start, u64 *end, u64 max_bytes) | |
d1310b2e CM |
1093 | { |
1094 | struct rb_node *node; | |
1095 | struct extent_state *state; | |
1096 | u64 cur_start = *start; | |
1097 | u64 found = 0; | |
1098 | u64 total_bytes = 0; | |
1099 | ||
70dec807 | 1100 | spin_lock_irq(&tree->lock); |
c8b97818 | 1101 | |
d1310b2e CM |
1102 | /* |
1103 | * this search will find all the extents that end after | |
1104 | * our range starts. | |
1105 | */ | |
80ea96b1 | 1106 | node = tree_search(tree, cur_start); |
2b114d1d | 1107 | if (!node) { |
3b951516 CM |
1108 | if (!found) |
1109 | *end = (u64)-1; | |
d1310b2e CM |
1110 | goto out; |
1111 | } | |
1112 | ||
1113 | while(1) { | |
1114 | state = rb_entry(node, struct extent_state, rb_node); | |
5b21f2ed ZY |
1115 | if (found && (state->start != cur_start || |
1116 | (state->state & EXTENT_BOUNDARY))) { | |
d1310b2e CM |
1117 | goto out; |
1118 | } | |
1119 | if (!(state->state & EXTENT_DELALLOC)) { | |
1120 | if (!found) | |
1121 | *end = state->end; | |
1122 | goto out; | |
1123 | } | |
d1310b2e CM |
1124 | if (!found) |
1125 | *start = state->start; | |
1126 | found++; | |
1127 | *end = state->end; | |
1128 | cur_start = state->end + 1; | |
1129 | node = rb_next(node); | |
1130 | if (!node) | |
1131 | break; | |
1132 | total_bytes += state->end - state->start + 1; | |
1133 | if (total_bytes >= max_bytes) | |
1134 | break; | |
1135 | } | |
1136 | out: | |
70dec807 | 1137 | spin_unlock_irq(&tree->lock); |
d1310b2e CM |
1138 | return found; |
1139 | } | |
1140 | ||
c8b97818 CM |
1141 | static noinline int __unlock_for_delalloc(struct inode *inode, |
1142 | struct page *locked_page, | |
1143 | u64 start, u64 end) | |
1144 | { | |
1145 | int ret; | |
1146 | struct page *pages[16]; | |
1147 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1148 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
1149 | unsigned long nr_pages = end_index - index + 1; | |
1150 | int i; | |
1151 | ||
1152 | if (index == locked_page->index && end_index == index) | |
1153 | return 0; | |
1154 | ||
1155 | while(nr_pages > 0) { | |
1156 | ret = find_get_pages_contig(inode->i_mapping, index, | |
5b050f04 CM |
1157 | min_t(unsigned long, nr_pages, |
1158 | ARRAY_SIZE(pages)), pages); | |
c8b97818 CM |
1159 | for (i = 0; i < ret; i++) { |
1160 | if (pages[i] != locked_page) | |
1161 | unlock_page(pages[i]); | |
1162 | page_cache_release(pages[i]); | |
1163 | } | |
1164 | nr_pages -= ret; | |
1165 | index += ret; | |
1166 | cond_resched(); | |
1167 | } | |
1168 | return 0; | |
1169 | } | |
1170 | ||
1171 | static noinline int lock_delalloc_pages(struct inode *inode, | |
1172 | struct page *locked_page, | |
1173 | u64 delalloc_start, | |
1174 | u64 delalloc_end) | |
1175 | { | |
1176 | unsigned long index = delalloc_start >> PAGE_CACHE_SHIFT; | |
1177 | unsigned long start_index = index; | |
1178 | unsigned long end_index = delalloc_end >> PAGE_CACHE_SHIFT; | |
1179 | unsigned long pages_locked = 0; | |
1180 | struct page *pages[16]; | |
1181 | unsigned long nrpages; | |
1182 | int ret; | |
1183 | int i; | |
1184 | ||
1185 | /* the caller is responsible for locking the start index */ | |
1186 | if (index == locked_page->index && index == end_index) | |
1187 | return 0; | |
1188 | ||
1189 | /* skip the page at the start index */ | |
1190 | nrpages = end_index - index + 1; | |
1191 | while(nrpages > 0) { | |
1192 | ret = find_get_pages_contig(inode->i_mapping, index, | |
5b050f04 CM |
1193 | min_t(unsigned long, |
1194 | nrpages, ARRAY_SIZE(pages)), pages); | |
c8b97818 CM |
1195 | if (ret == 0) { |
1196 | ret = -EAGAIN; | |
1197 | goto done; | |
1198 | } | |
1199 | /* now we have an array of pages, lock them all */ | |
1200 | for (i = 0; i < ret; i++) { | |
1201 | /* | |
1202 | * the caller is taking responsibility for | |
1203 | * locked_page | |
1204 | */ | |
771ed689 | 1205 | if (pages[i] != locked_page) { |
c8b97818 | 1206 | lock_page(pages[i]); |
f2b1c41c CM |
1207 | if (!PageDirty(pages[i]) || |
1208 | pages[i]->mapping != inode->i_mapping) { | |
771ed689 CM |
1209 | ret = -EAGAIN; |
1210 | unlock_page(pages[i]); | |
1211 | page_cache_release(pages[i]); | |
1212 | goto done; | |
1213 | } | |
1214 | } | |
c8b97818 | 1215 | page_cache_release(pages[i]); |
771ed689 | 1216 | pages_locked++; |
c8b97818 | 1217 | } |
c8b97818 CM |
1218 | nrpages -= ret; |
1219 | index += ret; | |
1220 | cond_resched(); | |
1221 | } | |
1222 | ret = 0; | |
1223 | done: | |
1224 | if (ret && pages_locked) { | |
1225 | __unlock_for_delalloc(inode, locked_page, | |
1226 | delalloc_start, | |
1227 | ((u64)(start_index + pages_locked - 1)) << | |
1228 | PAGE_CACHE_SHIFT); | |
1229 | } | |
1230 | return ret; | |
1231 | } | |
1232 | ||
1233 | /* | |
1234 | * find a contiguous range of bytes in the file marked as delalloc, not | |
1235 | * more than 'max_bytes'. start and end are used to return the range, | |
1236 | * | |
1237 | * 1 is returned if we find something, 0 if nothing was in the tree | |
1238 | */ | |
1239 | static noinline u64 find_lock_delalloc_range(struct inode *inode, | |
1240 | struct extent_io_tree *tree, | |
1241 | struct page *locked_page, | |
1242 | u64 *start, u64 *end, | |
1243 | u64 max_bytes) | |
1244 | { | |
1245 | u64 delalloc_start; | |
1246 | u64 delalloc_end; | |
1247 | u64 found; | |
1248 | int ret; | |
1249 | int loops = 0; | |
1250 | ||
1251 | again: | |
1252 | /* step one, find a bunch of delalloc bytes starting at start */ | |
1253 | delalloc_start = *start; | |
1254 | delalloc_end = 0; | |
1255 | found = find_delalloc_range(tree, &delalloc_start, &delalloc_end, | |
1256 | max_bytes); | |
70b99e69 | 1257 | if (!found || delalloc_end <= *start) { |
c8b97818 CM |
1258 | *start = delalloc_start; |
1259 | *end = delalloc_end; | |
1260 | return found; | |
1261 | } | |
1262 | ||
70b99e69 CM |
1263 | /* |
1264 | * start comes from the offset of locked_page. We have to lock | |
1265 | * pages in order, so we can't process delalloc bytes before | |
1266 | * locked_page | |
1267 | */ | |
1268 | if (delalloc_start < *start) { | |
1269 | delalloc_start = *start; | |
1270 | } | |
1271 | ||
c8b97818 CM |
1272 | /* |
1273 | * make sure to limit the number of pages we try to lock down | |
1274 | * if we're looping. | |
1275 | */ | |
1276 | if (delalloc_end + 1 - delalloc_start > max_bytes && loops) { | |
771ed689 | 1277 | delalloc_end = delalloc_start + PAGE_CACHE_SIZE - 1; |
c8b97818 CM |
1278 | } |
1279 | /* step two, lock all the pages after the page that has start */ | |
1280 | ret = lock_delalloc_pages(inode, locked_page, | |
1281 | delalloc_start, delalloc_end); | |
1282 | if (ret == -EAGAIN) { | |
1283 | /* some of the pages are gone, lets avoid looping by | |
1284 | * shortening the size of the delalloc range we're searching | |
1285 | */ | |
1286 | if (!loops) { | |
1287 | unsigned long offset = (*start) & (PAGE_CACHE_SIZE - 1); | |
1288 | max_bytes = PAGE_CACHE_SIZE - offset; | |
1289 | loops = 1; | |
1290 | goto again; | |
1291 | } else { | |
1292 | found = 0; | |
1293 | goto out_failed; | |
1294 | } | |
1295 | } | |
1296 | BUG_ON(ret); | |
1297 | ||
1298 | /* step three, lock the state bits for the whole range */ | |
1299 | lock_extent(tree, delalloc_start, delalloc_end, GFP_NOFS); | |
1300 | ||
1301 | /* then test to make sure it is all still delalloc */ | |
1302 | ret = test_range_bit(tree, delalloc_start, delalloc_end, | |
1303 | EXTENT_DELALLOC, 1); | |
1304 | if (!ret) { | |
1305 | unlock_extent(tree, delalloc_start, delalloc_end, GFP_NOFS); | |
1306 | __unlock_for_delalloc(inode, locked_page, | |
1307 | delalloc_start, delalloc_end); | |
1308 | cond_resched(); | |
1309 | goto again; | |
1310 | } | |
1311 | *start = delalloc_start; | |
1312 | *end = delalloc_end; | |
1313 | out_failed: | |
1314 | return found; | |
1315 | } | |
1316 | ||
1317 | int extent_clear_unlock_delalloc(struct inode *inode, | |
1318 | struct extent_io_tree *tree, | |
1319 | u64 start, u64 end, struct page *locked_page, | |
771ed689 CM |
1320 | int unlock_pages, |
1321 | int clear_unlock, | |
1322 | int clear_delalloc, int clear_dirty, | |
1323 | int set_writeback, | |
c8b97818 CM |
1324 | int end_writeback) |
1325 | { | |
1326 | int ret; | |
1327 | struct page *pages[16]; | |
1328 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1329 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
1330 | unsigned long nr_pages = end_index - index + 1; | |
1331 | int i; | |
771ed689 | 1332 | int clear_bits = 0; |
c8b97818 | 1333 | |
771ed689 CM |
1334 | if (clear_unlock) |
1335 | clear_bits |= EXTENT_LOCKED; | |
c8b97818 CM |
1336 | if (clear_dirty) |
1337 | clear_bits |= EXTENT_DIRTY; | |
1338 | ||
771ed689 CM |
1339 | if (clear_delalloc) |
1340 | clear_bits |= EXTENT_DELALLOC; | |
1341 | ||
c8b97818 | 1342 | clear_extent_bit(tree, start, end, clear_bits, 1, 0, GFP_NOFS); |
771ed689 CM |
1343 | if (!(unlock_pages || clear_dirty || set_writeback || end_writeback)) |
1344 | return 0; | |
c8b97818 CM |
1345 | |
1346 | while(nr_pages > 0) { | |
1347 | ret = find_get_pages_contig(inode->i_mapping, index, | |
5b050f04 CM |
1348 | min_t(unsigned long, |
1349 | nr_pages, ARRAY_SIZE(pages)), pages); | |
c8b97818 CM |
1350 | for (i = 0; i < ret; i++) { |
1351 | if (pages[i] == locked_page) { | |
1352 | page_cache_release(pages[i]); | |
1353 | continue; | |
1354 | } | |
1355 | if (clear_dirty) | |
1356 | clear_page_dirty_for_io(pages[i]); | |
1357 | if (set_writeback) | |
1358 | set_page_writeback(pages[i]); | |
1359 | if (end_writeback) | |
1360 | end_page_writeback(pages[i]); | |
771ed689 CM |
1361 | if (unlock_pages) |
1362 | unlock_page(pages[i]); | |
c8b97818 CM |
1363 | page_cache_release(pages[i]); |
1364 | } | |
1365 | nr_pages -= ret; | |
1366 | index += ret; | |
1367 | cond_resched(); | |
1368 | } | |
1369 | return 0; | |
1370 | } | |
1371 | EXPORT_SYMBOL(extent_clear_unlock_delalloc); | |
1372 | ||
d352ac68 CM |
1373 | /* |
1374 | * count the number of bytes in the tree that have a given bit(s) | |
1375 | * set. This can be fairly slow, except for EXTENT_DIRTY which is | |
1376 | * cached. The total number found is returned. | |
1377 | */ | |
d1310b2e CM |
1378 | u64 count_range_bits(struct extent_io_tree *tree, |
1379 | u64 *start, u64 search_end, u64 max_bytes, | |
1380 | unsigned long bits) | |
1381 | { | |
1382 | struct rb_node *node; | |
1383 | struct extent_state *state; | |
1384 | u64 cur_start = *start; | |
1385 | u64 total_bytes = 0; | |
1386 | int found = 0; | |
1387 | ||
1388 | if (search_end <= cur_start) { | |
1389 | printk("search_end %Lu start %Lu\n", search_end, cur_start); | |
1390 | WARN_ON(1); | |
1391 | return 0; | |
1392 | } | |
1393 | ||
70dec807 | 1394 | spin_lock_irq(&tree->lock); |
d1310b2e CM |
1395 | if (cur_start == 0 && bits == EXTENT_DIRTY) { |
1396 | total_bytes = tree->dirty_bytes; | |
1397 | goto out; | |
1398 | } | |
1399 | /* | |
1400 | * this search will find all the extents that end after | |
1401 | * our range starts. | |
1402 | */ | |
80ea96b1 | 1403 | node = tree_search(tree, cur_start); |
2b114d1d | 1404 | if (!node) { |
d1310b2e CM |
1405 | goto out; |
1406 | } | |
1407 | ||
1408 | while(1) { | |
1409 | state = rb_entry(node, struct extent_state, rb_node); | |
1410 | if (state->start > search_end) | |
1411 | break; | |
1412 | if (state->end >= cur_start && (state->state & bits)) { | |
1413 | total_bytes += min(search_end, state->end) + 1 - | |
1414 | max(cur_start, state->start); | |
1415 | if (total_bytes >= max_bytes) | |
1416 | break; | |
1417 | if (!found) { | |
1418 | *start = state->start; | |
1419 | found = 1; | |
1420 | } | |
1421 | } | |
1422 | node = rb_next(node); | |
1423 | if (!node) | |
1424 | break; | |
1425 | } | |
1426 | out: | |
70dec807 | 1427 | spin_unlock_irq(&tree->lock); |
d1310b2e CM |
1428 | return total_bytes; |
1429 | } | |
b2950863 CH |
1430 | |
1431 | #if 0 | |
d1310b2e CM |
1432 | /* |
1433 | * helper function to lock both pages and extents in the tree. | |
1434 | * pages must be locked first. | |
1435 | */ | |
b2950863 | 1436 | static int lock_range(struct extent_io_tree *tree, u64 start, u64 end) |
d1310b2e CM |
1437 | { |
1438 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1439 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
1440 | struct page *page; | |
1441 | int err; | |
1442 | ||
1443 | while (index <= end_index) { | |
1444 | page = grab_cache_page(tree->mapping, index); | |
1445 | if (!page) { | |
1446 | err = -ENOMEM; | |
1447 | goto failed; | |
1448 | } | |
1449 | if (IS_ERR(page)) { | |
1450 | err = PTR_ERR(page); | |
1451 | goto failed; | |
1452 | } | |
1453 | index++; | |
1454 | } | |
1455 | lock_extent(tree, start, end, GFP_NOFS); | |
1456 | return 0; | |
1457 | ||
1458 | failed: | |
1459 | /* | |
1460 | * we failed above in getting the page at 'index', so we undo here | |
1461 | * up to but not including the page at 'index' | |
1462 | */ | |
1463 | end_index = index; | |
1464 | index = start >> PAGE_CACHE_SHIFT; | |
1465 | while (index < end_index) { | |
1466 | page = find_get_page(tree->mapping, index); | |
1467 | unlock_page(page); | |
1468 | page_cache_release(page); | |
1469 | index++; | |
1470 | } | |
1471 | return err; | |
1472 | } | |
d1310b2e CM |
1473 | |
1474 | /* | |
1475 | * helper function to unlock both pages and extents in the tree. | |
1476 | */ | |
b2950863 | 1477 | static int unlock_range(struct extent_io_tree *tree, u64 start, u64 end) |
d1310b2e CM |
1478 | { |
1479 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1480 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
1481 | struct page *page; | |
1482 | ||
1483 | while (index <= end_index) { | |
1484 | page = find_get_page(tree->mapping, index); | |
1485 | unlock_page(page); | |
1486 | page_cache_release(page); | |
1487 | index++; | |
1488 | } | |
1489 | unlock_extent(tree, start, end, GFP_NOFS); | |
1490 | return 0; | |
1491 | } | |
b2950863 | 1492 | #endif |
d1310b2e | 1493 | |
d352ac68 CM |
1494 | /* |
1495 | * set the private field for a given byte offset in the tree. If there isn't | |
1496 | * an extent_state there already, this does nothing. | |
1497 | */ | |
d1310b2e CM |
1498 | int set_state_private(struct extent_io_tree *tree, u64 start, u64 private) |
1499 | { | |
1500 | struct rb_node *node; | |
1501 | struct extent_state *state; | |
1502 | int ret = 0; | |
1503 | ||
70dec807 | 1504 | spin_lock_irq(&tree->lock); |
d1310b2e CM |
1505 | /* |
1506 | * this search will find all the extents that end after | |
1507 | * our range starts. | |
1508 | */ | |
80ea96b1 | 1509 | node = tree_search(tree, start); |
2b114d1d | 1510 | if (!node) { |
d1310b2e CM |
1511 | ret = -ENOENT; |
1512 | goto out; | |
1513 | } | |
1514 | state = rb_entry(node, struct extent_state, rb_node); | |
1515 | if (state->start != start) { | |
1516 | ret = -ENOENT; | |
1517 | goto out; | |
1518 | } | |
1519 | state->private = private; | |
1520 | out: | |
70dec807 | 1521 | spin_unlock_irq(&tree->lock); |
d1310b2e CM |
1522 | return ret; |
1523 | } | |
1524 | ||
1525 | int get_state_private(struct extent_io_tree *tree, u64 start, u64 *private) | |
1526 | { | |
1527 | struct rb_node *node; | |
1528 | struct extent_state *state; | |
1529 | int ret = 0; | |
1530 | ||
70dec807 | 1531 | spin_lock_irq(&tree->lock); |
d1310b2e CM |
1532 | /* |
1533 | * this search will find all the extents that end after | |
1534 | * our range starts. | |
1535 | */ | |
80ea96b1 | 1536 | node = tree_search(tree, start); |
2b114d1d | 1537 | if (!node) { |
d1310b2e CM |
1538 | ret = -ENOENT; |
1539 | goto out; | |
1540 | } | |
1541 | state = rb_entry(node, struct extent_state, rb_node); | |
1542 | if (state->start != start) { | |
1543 | ret = -ENOENT; | |
1544 | goto out; | |
1545 | } | |
1546 | *private = state->private; | |
1547 | out: | |
70dec807 | 1548 | spin_unlock_irq(&tree->lock); |
d1310b2e CM |
1549 | return ret; |
1550 | } | |
1551 | ||
1552 | /* | |
1553 | * searches a range in the state tree for a given mask. | |
70dec807 | 1554 | * If 'filled' == 1, this returns 1 only if every extent in the tree |
d1310b2e CM |
1555 | * has the bits set. Otherwise, 1 is returned if any bit in the |
1556 | * range is found set. | |
1557 | */ | |
1558 | int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end, | |
1559 | int bits, int filled) | |
1560 | { | |
1561 | struct extent_state *state = NULL; | |
1562 | struct rb_node *node; | |
1563 | int bitset = 0; | |
1564 | unsigned long flags; | |
1565 | ||
70dec807 | 1566 | spin_lock_irqsave(&tree->lock, flags); |
80ea96b1 | 1567 | node = tree_search(tree, start); |
d1310b2e CM |
1568 | while (node && start <= end) { |
1569 | state = rb_entry(node, struct extent_state, rb_node); | |
1570 | ||
1571 | if (filled && state->start > start) { | |
1572 | bitset = 0; | |
1573 | break; | |
1574 | } | |
1575 | ||
1576 | if (state->start > end) | |
1577 | break; | |
1578 | ||
1579 | if (state->state & bits) { | |
1580 | bitset = 1; | |
1581 | if (!filled) | |
1582 | break; | |
1583 | } else if (filled) { | |
1584 | bitset = 0; | |
1585 | break; | |
1586 | } | |
1587 | start = state->end + 1; | |
1588 | if (start > end) | |
1589 | break; | |
1590 | node = rb_next(node); | |
1591 | if (!node) { | |
1592 | if (filled) | |
1593 | bitset = 0; | |
1594 | break; | |
1595 | } | |
1596 | } | |
70dec807 | 1597 | spin_unlock_irqrestore(&tree->lock, flags); |
d1310b2e CM |
1598 | return bitset; |
1599 | } | |
1600 | EXPORT_SYMBOL(test_range_bit); | |
1601 | ||
1602 | /* | |
1603 | * helper function to set a given page up to date if all the | |
1604 | * extents in the tree for that page are up to date | |
1605 | */ | |
1606 | static int check_page_uptodate(struct extent_io_tree *tree, | |
1607 | struct page *page) | |
1608 | { | |
1609 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
1610 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
1611 | if (test_range_bit(tree, start, end, EXTENT_UPTODATE, 1)) | |
1612 | SetPageUptodate(page); | |
1613 | return 0; | |
1614 | } | |
1615 | ||
1616 | /* | |
1617 | * helper function to unlock a page if all the extents in the tree | |
1618 | * for that page are unlocked | |
1619 | */ | |
1620 | static int check_page_locked(struct extent_io_tree *tree, | |
1621 | struct page *page) | |
1622 | { | |
1623 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
1624 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
1625 | if (!test_range_bit(tree, start, end, EXTENT_LOCKED, 0)) | |
1626 | unlock_page(page); | |
1627 | return 0; | |
1628 | } | |
1629 | ||
1630 | /* | |
1631 | * helper function to end page writeback if all the extents | |
1632 | * in the tree for that page are done with writeback | |
1633 | */ | |
1634 | static int check_page_writeback(struct extent_io_tree *tree, | |
1635 | struct page *page) | |
1636 | { | |
1637 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
1638 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
1639 | if (!test_range_bit(tree, start, end, EXTENT_WRITEBACK, 0)) | |
1640 | end_page_writeback(page); | |
1641 | return 0; | |
1642 | } | |
1643 | ||
1644 | /* lots and lots of room for performance fixes in the end_bio funcs */ | |
1645 | ||
1646 | /* | |
1647 | * after a writepage IO is done, we need to: | |
1648 | * clear the uptodate bits on error | |
1649 | * clear the writeback bits in the extent tree for this IO | |
1650 | * end_page_writeback if the page has no more pending IO | |
1651 | * | |
1652 | * Scheduling is not allowed, so the extent state tree is expected | |
1653 | * to have one and only one object corresponding to this IO. | |
1654 | */ | |
d1310b2e | 1655 | static void end_bio_extent_writepage(struct bio *bio, int err) |
d1310b2e | 1656 | { |
1259ab75 | 1657 | int uptodate = err == 0; |
d1310b2e | 1658 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; |
902b22f3 | 1659 | struct extent_io_tree *tree; |
d1310b2e CM |
1660 | u64 start; |
1661 | u64 end; | |
1662 | int whole_page; | |
1259ab75 | 1663 | int ret; |
d1310b2e | 1664 | |
d1310b2e CM |
1665 | do { |
1666 | struct page *page = bvec->bv_page; | |
902b22f3 DW |
1667 | tree = &BTRFS_I(page->mapping->host)->io_tree; |
1668 | ||
d1310b2e CM |
1669 | start = ((u64)page->index << PAGE_CACHE_SHIFT) + |
1670 | bvec->bv_offset; | |
1671 | end = start + bvec->bv_len - 1; | |
1672 | ||
1673 | if (bvec->bv_offset == 0 && bvec->bv_len == PAGE_CACHE_SIZE) | |
1674 | whole_page = 1; | |
1675 | else | |
1676 | whole_page = 0; | |
1677 | ||
1678 | if (--bvec >= bio->bi_io_vec) | |
1679 | prefetchw(&bvec->bv_page->flags); | |
1259ab75 CM |
1680 | if (tree->ops && tree->ops->writepage_end_io_hook) { |
1681 | ret = tree->ops->writepage_end_io_hook(page, start, | |
902b22f3 | 1682 | end, NULL, uptodate); |
1259ab75 CM |
1683 | if (ret) |
1684 | uptodate = 0; | |
1685 | } | |
1686 | ||
1687 | if (!uptodate && tree->ops && | |
1688 | tree->ops->writepage_io_failed_hook) { | |
1689 | ret = tree->ops->writepage_io_failed_hook(bio, page, | |
902b22f3 | 1690 | start, end, NULL); |
1259ab75 | 1691 | if (ret == 0) { |
1259ab75 CM |
1692 | uptodate = (err == 0); |
1693 | continue; | |
1694 | } | |
1695 | } | |
1696 | ||
d1310b2e CM |
1697 | if (!uptodate) { |
1698 | clear_extent_uptodate(tree, start, end, GFP_ATOMIC); | |
1699 | ClearPageUptodate(page); | |
1700 | SetPageError(page); | |
1701 | } | |
70dec807 | 1702 | |
902b22f3 | 1703 | clear_extent_writeback(tree, start, end, GFP_ATOMIC); |
d1310b2e CM |
1704 | |
1705 | if (whole_page) | |
1706 | end_page_writeback(page); | |
1707 | else | |
1708 | check_page_writeback(tree, page); | |
d1310b2e | 1709 | } while (bvec >= bio->bi_io_vec); |
2b1f55b0 | 1710 | |
d1310b2e | 1711 | bio_put(bio); |
d1310b2e CM |
1712 | } |
1713 | ||
1714 | /* | |
1715 | * after a readpage IO is done, we need to: | |
1716 | * clear the uptodate bits on error | |
1717 | * set the uptodate bits if things worked | |
1718 | * set the page up to date if all extents in the tree are uptodate | |
1719 | * clear the lock bit in the extent tree | |
1720 | * unlock the page if there are no other extents locked for it | |
1721 | * | |
1722 | * Scheduling is not allowed, so the extent state tree is expected | |
1723 | * to have one and only one object corresponding to this IO. | |
1724 | */ | |
d1310b2e | 1725 | static void end_bio_extent_readpage(struct bio *bio, int err) |
d1310b2e CM |
1726 | { |
1727 | int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); | |
1728 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; | |
902b22f3 | 1729 | struct extent_io_tree *tree; |
d1310b2e CM |
1730 | u64 start; |
1731 | u64 end; | |
1732 | int whole_page; | |
1733 | int ret; | |
1734 | ||
d20f7043 CM |
1735 | if (err) |
1736 | uptodate = 0; | |
1737 | ||
d1310b2e CM |
1738 | do { |
1739 | struct page *page = bvec->bv_page; | |
902b22f3 DW |
1740 | tree = &BTRFS_I(page->mapping->host)->io_tree; |
1741 | ||
d1310b2e CM |
1742 | start = ((u64)page->index << PAGE_CACHE_SHIFT) + |
1743 | bvec->bv_offset; | |
1744 | end = start + bvec->bv_len - 1; | |
1745 | ||
1746 | if (bvec->bv_offset == 0 && bvec->bv_len == PAGE_CACHE_SIZE) | |
1747 | whole_page = 1; | |
1748 | else | |
1749 | whole_page = 0; | |
1750 | ||
1751 | if (--bvec >= bio->bi_io_vec) | |
1752 | prefetchw(&bvec->bv_page->flags); | |
1753 | ||
1754 | if (uptodate && tree->ops && tree->ops->readpage_end_io_hook) { | |
70dec807 | 1755 | ret = tree->ops->readpage_end_io_hook(page, start, end, |
902b22f3 | 1756 | NULL); |
d1310b2e CM |
1757 | if (ret) |
1758 | uptodate = 0; | |
1759 | } | |
7e38326f CM |
1760 | if (!uptodate && tree->ops && |
1761 | tree->ops->readpage_io_failed_hook) { | |
1762 | ret = tree->ops->readpage_io_failed_hook(bio, page, | |
902b22f3 | 1763 | start, end, NULL); |
7e38326f | 1764 | if (ret == 0) { |
3b951516 CM |
1765 | uptodate = |
1766 | test_bit(BIO_UPTODATE, &bio->bi_flags); | |
d20f7043 CM |
1767 | if (err) |
1768 | uptodate = 0; | |
7e38326f CM |
1769 | continue; |
1770 | } | |
1771 | } | |
d1310b2e | 1772 | |
771ed689 | 1773 | if (uptodate) { |
902b22f3 DW |
1774 | set_extent_uptodate(tree, start, end, |
1775 | GFP_ATOMIC); | |
771ed689 | 1776 | } |
902b22f3 | 1777 | unlock_extent(tree, start, end, GFP_ATOMIC); |
d1310b2e | 1778 | |
70dec807 CM |
1779 | if (whole_page) { |
1780 | if (uptodate) { | |
1781 | SetPageUptodate(page); | |
1782 | } else { | |
1783 | ClearPageUptodate(page); | |
1784 | SetPageError(page); | |
1785 | } | |
d1310b2e | 1786 | unlock_page(page); |
70dec807 CM |
1787 | } else { |
1788 | if (uptodate) { | |
1789 | check_page_uptodate(tree, page); | |
1790 | } else { | |
1791 | ClearPageUptodate(page); | |
1792 | SetPageError(page); | |
1793 | } | |
d1310b2e | 1794 | check_page_locked(tree, page); |
70dec807 | 1795 | } |
d1310b2e CM |
1796 | } while (bvec >= bio->bi_io_vec); |
1797 | ||
1798 | bio_put(bio); | |
d1310b2e CM |
1799 | } |
1800 | ||
1801 | /* | |
1802 | * IO done from prepare_write is pretty simple, we just unlock | |
1803 | * the structs in the extent tree when done, and set the uptodate bits | |
1804 | * as appropriate. | |
1805 | */ | |
d1310b2e | 1806 | static void end_bio_extent_preparewrite(struct bio *bio, int err) |
d1310b2e CM |
1807 | { |
1808 | const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); | |
1809 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; | |
902b22f3 | 1810 | struct extent_io_tree *tree; |
d1310b2e CM |
1811 | u64 start; |
1812 | u64 end; | |
1813 | ||
d1310b2e CM |
1814 | do { |
1815 | struct page *page = bvec->bv_page; | |
902b22f3 DW |
1816 | tree = &BTRFS_I(page->mapping->host)->io_tree; |
1817 | ||
d1310b2e CM |
1818 | start = ((u64)page->index << PAGE_CACHE_SHIFT) + |
1819 | bvec->bv_offset; | |
1820 | end = start + bvec->bv_len - 1; | |
1821 | ||
1822 | if (--bvec >= bio->bi_io_vec) | |
1823 | prefetchw(&bvec->bv_page->flags); | |
1824 | ||
1825 | if (uptodate) { | |
1826 | set_extent_uptodate(tree, start, end, GFP_ATOMIC); | |
1827 | } else { | |
1828 | ClearPageUptodate(page); | |
1829 | SetPageError(page); | |
1830 | } | |
1831 | ||
1832 | unlock_extent(tree, start, end, GFP_ATOMIC); | |
1833 | ||
1834 | } while (bvec >= bio->bi_io_vec); | |
1835 | ||
1836 | bio_put(bio); | |
d1310b2e CM |
1837 | } |
1838 | ||
1839 | static struct bio * | |
1840 | extent_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs, | |
1841 | gfp_t gfp_flags) | |
1842 | { | |
1843 | struct bio *bio; | |
1844 | ||
1845 | bio = bio_alloc(gfp_flags, nr_vecs); | |
1846 | ||
1847 | if (bio == NULL && (current->flags & PF_MEMALLOC)) { | |
1848 | while (!bio && (nr_vecs /= 2)) | |
1849 | bio = bio_alloc(gfp_flags, nr_vecs); | |
1850 | } | |
1851 | ||
1852 | if (bio) { | |
e1c4b745 | 1853 | bio->bi_size = 0; |
d1310b2e CM |
1854 | bio->bi_bdev = bdev; |
1855 | bio->bi_sector = first_sector; | |
1856 | } | |
1857 | return bio; | |
1858 | } | |
1859 | ||
c8b97818 CM |
1860 | static int submit_one_bio(int rw, struct bio *bio, int mirror_num, |
1861 | unsigned long bio_flags) | |
d1310b2e | 1862 | { |
d1310b2e | 1863 | int ret = 0; |
70dec807 CM |
1864 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; |
1865 | struct page *page = bvec->bv_page; | |
1866 | struct extent_io_tree *tree = bio->bi_private; | |
70dec807 CM |
1867 | u64 start; |
1868 | u64 end; | |
1869 | ||
1870 | start = ((u64)page->index << PAGE_CACHE_SHIFT) + bvec->bv_offset; | |
1871 | end = start + bvec->bv_len - 1; | |
1872 | ||
902b22f3 | 1873 | bio->bi_private = NULL; |
d1310b2e CM |
1874 | |
1875 | bio_get(bio); | |
1876 | ||
065631f6 | 1877 | if (tree->ops && tree->ops->submit_bio_hook) |
f188591e | 1878 | tree->ops->submit_bio_hook(page->mapping->host, rw, bio, |
c8b97818 | 1879 | mirror_num, bio_flags); |
0b86a832 CM |
1880 | else |
1881 | submit_bio(rw, bio); | |
d1310b2e CM |
1882 | if (bio_flagged(bio, BIO_EOPNOTSUPP)) |
1883 | ret = -EOPNOTSUPP; | |
1884 | bio_put(bio); | |
1885 | return ret; | |
1886 | } | |
1887 | ||
1888 | static int submit_extent_page(int rw, struct extent_io_tree *tree, | |
1889 | struct page *page, sector_t sector, | |
1890 | size_t size, unsigned long offset, | |
1891 | struct block_device *bdev, | |
1892 | struct bio **bio_ret, | |
1893 | unsigned long max_pages, | |
f188591e | 1894 | bio_end_io_t end_io_func, |
c8b97818 CM |
1895 | int mirror_num, |
1896 | unsigned long prev_bio_flags, | |
1897 | unsigned long bio_flags) | |
d1310b2e CM |
1898 | { |
1899 | int ret = 0; | |
1900 | struct bio *bio; | |
1901 | int nr; | |
c8b97818 CM |
1902 | int contig = 0; |
1903 | int this_compressed = bio_flags & EXTENT_BIO_COMPRESSED; | |
1904 | int old_compressed = prev_bio_flags & EXTENT_BIO_COMPRESSED; | |
5b050f04 | 1905 | size_t page_size = min_t(size_t, size, PAGE_CACHE_SIZE); |
d1310b2e CM |
1906 | |
1907 | if (bio_ret && *bio_ret) { | |
1908 | bio = *bio_ret; | |
c8b97818 CM |
1909 | if (old_compressed) |
1910 | contig = bio->bi_sector == sector; | |
1911 | else | |
1912 | contig = bio->bi_sector + (bio->bi_size >> 9) == | |
1913 | sector; | |
1914 | ||
1915 | if (prev_bio_flags != bio_flags || !contig || | |
239b14b3 | 1916 | (tree->ops && tree->ops->merge_bio_hook && |
c8b97818 CM |
1917 | tree->ops->merge_bio_hook(page, offset, page_size, bio, |
1918 | bio_flags)) || | |
1919 | bio_add_page(bio, page, page_size, offset) < page_size) { | |
1920 | ret = submit_one_bio(rw, bio, mirror_num, | |
1921 | prev_bio_flags); | |
d1310b2e CM |
1922 | bio = NULL; |
1923 | } else { | |
1924 | return 0; | |
1925 | } | |
1926 | } | |
c8b97818 CM |
1927 | if (this_compressed) |
1928 | nr = BIO_MAX_PAGES; | |
1929 | else | |
1930 | nr = bio_get_nr_vecs(bdev); | |
1931 | ||
d1310b2e CM |
1932 | bio = extent_bio_alloc(bdev, sector, nr, GFP_NOFS | __GFP_HIGH); |
1933 | if (!bio) { | |
1934 | printk("failed to allocate bio nr %d\n", nr); | |
1935 | } | |
70dec807 | 1936 | |
c8b97818 | 1937 | bio_add_page(bio, page, page_size, offset); |
d1310b2e CM |
1938 | bio->bi_end_io = end_io_func; |
1939 | bio->bi_private = tree; | |
70dec807 | 1940 | |
d1310b2e CM |
1941 | if (bio_ret) { |
1942 | *bio_ret = bio; | |
1943 | } else { | |
c8b97818 | 1944 | ret = submit_one_bio(rw, bio, mirror_num, bio_flags); |
d1310b2e CM |
1945 | } |
1946 | ||
1947 | return ret; | |
1948 | } | |
1949 | ||
1950 | void set_page_extent_mapped(struct page *page) | |
1951 | { | |
1952 | if (!PagePrivate(page)) { | |
1953 | SetPagePrivate(page); | |
d1310b2e | 1954 | page_cache_get(page); |
6af118ce | 1955 | set_page_private(page, EXTENT_PAGE_PRIVATE); |
d1310b2e CM |
1956 | } |
1957 | } | |
771ed689 | 1958 | EXPORT_SYMBOL(set_page_extent_mapped); |
d1310b2e | 1959 | |
b2950863 | 1960 | static void set_page_extent_head(struct page *page, unsigned long len) |
d1310b2e CM |
1961 | { |
1962 | set_page_private(page, EXTENT_PAGE_PRIVATE_FIRST_PAGE | len << 2); | |
1963 | } | |
1964 | ||
1965 | /* | |
1966 | * basic readpage implementation. Locked extent state structs are inserted | |
1967 | * into the tree that are removed when the IO is done (by the end_io | |
1968 | * handlers) | |
1969 | */ | |
1970 | static int __extent_read_full_page(struct extent_io_tree *tree, | |
1971 | struct page *page, | |
1972 | get_extent_t *get_extent, | |
c8b97818 CM |
1973 | struct bio **bio, int mirror_num, |
1974 | unsigned long *bio_flags) | |
d1310b2e CM |
1975 | { |
1976 | struct inode *inode = page->mapping->host; | |
1977 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
1978 | u64 page_end = start + PAGE_CACHE_SIZE - 1; | |
1979 | u64 end; | |
1980 | u64 cur = start; | |
1981 | u64 extent_offset; | |
1982 | u64 last_byte = i_size_read(inode); | |
1983 | u64 block_start; | |
1984 | u64 cur_end; | |
1985 | sector_t sector; | |
1986 | struct extent_map *em; | |
1987 | struct block_device *bdev; | |
1988 | int ret; | |
1989 | int nr = 0; | |
1990 | size_t page_offset = 0; | |
1991 | size_t iosize; | |
c8b97818 | 1992 | size_t disk_io_size; |
d1310b2e | 1993 | size_t blocksize = inode->i_sb->s_blocksize; |
c8b97818 | 1994 | unsigned long this_bio_flag = 0; |
d1310b2e CM |
1995 | |
1996 | set_page_extent_mapped(page); | |
1997 | ||
1998 | end = page_end; | |
1999 | lock_extent(tree, start, end, GFP_NOFS); | |
2000 | ||
c8b97818 CM |
2001 | if (page->index == last_byte >> PAGE_CACHE_SHIFT) { |
2002 | char *userpage; | |
2003 | size_t zero_offset = last_byte & (PAGE_CACHE_SIZE - 1); | |
2004 | ||
2005 | if (zero_offset) { | |
2006 | iosize = PAGE_CACHE_SIZE - zero_offset; | |
2007 | userpage = kmap_atomic(page, KM_USER0); | |
2008 | memset(userpage + zero_offset, 0, iosize); | |
2009 | flush_dcache_page(page); | |
2010 | kunmap_atomic(userpage, KM_USER0); | |
2011 | } | |
2012 | } | |
d1310b2e CM |
2013 | while (cur <= end) { |
2014 | if (cur >= last_byte) { | |
2015 | char *userpage; | |
2016 | iosize = PAGE_CACHE_SIZE - page_offset; | |
2017 | userpage = kmap_atomic(page, KM_USER0); | |
2018 | memset(userpage + page_offset, 0, iosize); | |
2019 | flush_dcache_page(page); | |
2020 | kunmap_atomic(userpage, KM_USER0); | |
2021 | set_extent_uptodate(tree, cur, cur + iosize - 1, | |
2022 | GFP_NOFS); | |
2023 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); | |
2024 | break; | |
2025 | } | |
2026 | em = get_extent(inode, page, page_offset, cur, | |
2027 | end - cur + 1, 0); | |
2028 | if (IS_ERR(em) || !em) { | |
2029 | SetPageError(page); | |
2030 | unlock_extent(tree, cur, end, GFP_NOFS); | |
2031 | break; | |
2032 | } | |
d1310b2e | 2033 | extent_offset = cur - em->start; |
e6dcd2dc CM |
2034 | if (extent_map_end(em) <= cur) { |
2035 | printk("bad mapping em [%Lu %Lu] cur %Lu\n", em->start, extent_map_end(em), cur); | |
2036 | } | |
d1310b2e | 2037 | BUG_ON(extent_map_end(em) <= cur); |
e6dcd2dc CM |
2038 | if (end < cur) { |
2039 | printk("2bad mapping end %Lu cur %Lu\n", end, cur); | |
2040 | } | |
d1310b2e CM |
2041 | BUG_ON(end < cur); |
2042 | ||
c8b97818 CM |
2043 | if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) |
2044 | this_bio_flag = EXTENT_BIO_COMPRESSED; | |
2045 | ||
d1310b2e CM |
2046 | iosize = min(extent_map_end(em) - cur, end - cur + 1); |
2047 | cur_end = min(extent_map_end(em) - 1, end); | |
2048 | iosize = (iosize + blocksize - 1) & ~((u64)blocksize - 1); | |
c8b97818 CM |
2049 | if (this_bio_flag & EXTENT_BIO_COMPRESSED) { |
2050 | disk_io_size = em->block_len; | |
2051 | sector = em->block_start >> 9; | |
2052 | } else { | |
2053 | sector = (em->block_start + extent_offset) >> 9; | |
2054 | disk_io_size = iosize; | |
2055 | } | |
d1310b2e CM |
2056 | bdev = em->bdev; |
2057 | block_start = em->block_start; | |
d899e052 YZ |
2058 | if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) |
2059 | block_start = EXTENT_MAP_HOLE; | |
d1310b2e CM |
2060 | free_extent_map(em); |
2061 | em = NULL; | |
2062 | ||
2063 | /* we've found a hole, just zero and go on */ | |
2064 | if (block_start == EXTENT_MAP_HOLE) { | |
2065 | char *userpage; | |
2066 | userpage = kmap_atomic(page, KM_USER0); | |
2067 | memset(userpage + page_offset, 0, iosize); | |
2068 | flush_dcache_page(page); | |
2069 | kunmap_atomic(userpage, KM_USER0); | |
2070 | ||
2071 | set_extent_uptodate(tree, cur, cur + iosize - 1, | |
2072 | GFP_NOFS); | |
2073 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); | |
2074 | cur = cur + iosize; | |
2075 | page_offset += iosize; | |
2076 | continue; | |
2077 | } | |
2078 | /* the get_extent function already copied into the page */ | |
2079 | if (test_range_bit(tree, cur, cur_end, EXTENT_UPTODATE, 1)) { | |
a1b32a59 | 2080 | check_page_uptodate(tree, page); |
d1310b2e CM |
2081 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); |
2082 | cur = cur + iosize; | |
2083 | page_offset += iosize; | |
2084 | continue; | |
2085 | } | |
70dec807 CM |
2086 | /* we have an inline extent but it didn't get marked up |
2087 | * to date. Error out | |
2088 | */ | |
2089 | if (block_start == EXTENT_MAP_INLINE) { | |
2090 | SetPageError(page); | |
2091 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); | |
2092 | cur = cur + iosize; | |
2093 | page_offset += iosize; | |
2094 | continue; | |
2095 | } | |
d1310b2e CM |
2096 | |
2097 | ret = 0; | |
2098 | if (tree->ops && tree->ops->readpage_io_hook) { | |
2099 | ret = tree->ops->readpage_io_hook(page, cur, | |
2100 | cur + iosize - 1); | |
2101 | } | |
2102 | if (!ret) { | |
89642229 CM |
2103 | unsigned long pnr = (last_byte >> PAGE_CACHE_SHIFT) + 1; |
2104 | pnr -= page->index; | |
d1310b2e | 2105 | ret = submit_extent_page(READ, tree, page, |
c8b97818 | 2106 | sector, disk_io_size, page_offset, |
89642229 | 2107 | bdev, bio, pnr, |
c8b97818 CM |
2108 | end_bio_extent_readpage, mirror_num, |
2109 | *bio_flags, | |
2110 | this_bio_flag); | |
89642229 | 2111 | nr++; |
c8b97818 | 2112 | *bio_flags = this_bio_flag; |
d1310b2e CM |
2113 | } |
2114 | if (ret) | |
2115 | SetPageError(page); | |
2116 | cur = cur + iosize; | |
2117 | page_offset += iosize; | |
d1310b2e CM |
2118 | } |
2119 | if (!nr) { | |
2120 | if (!PageError(page)) | |
2121 | SetPageUptodate(page); | |
2122 | unlock_page(page); | |
2123 | } | |
2124 | return 0; | |
2125 | } | |
2126 | ||
2127 | int extent_read_full_page(struct extent_io_tree *tree, struct page *page, | |
2128 | get_extent_t *get_extent) | |
2129 | { | |
2130 | struct bio *bio = NULL; | |
c8b97818 | 2131 | unsigned long bio_flags = 0; |
d1310b2e CM |
2132 | int ret; |
2133 | ||
c8b97818 CM |
2134 | ret = __extent_read_full_page(tree, page, get_extent, &bio, 0, |
2135 | &bio_flags); | |
d1310b2e | 2136 | if (bio) |
c8b97818 | 2137 | submit_one_bio(READ, bio, 0, bio_flags); |
d1310b2e CM |
2138 | return ret; |
2139 | } | |
2140 | EXPORT_SYMBOL(extent_read_full_page); | |
2141 | ||
2142 | /* | |
2143 | * the writepage semantics are similar to regular writepage. extent | |
2144 | * records are inserted to lock ranges in the tree, and as dirty areas | |
2145 | * are found, they are marked writeback. Then the lock bits are removed | |
2146 | * and the end_io handler clears the writeback ranges | |
2147 | */ | |
2148 | static int __extent_writepage(struct page *page, struct writeback_control *wbc, | |
2149 | void *data) | |
2150 | { | |
2151 | struct inode *inode = page->mapping->host; | |
2152 | struct extent_page_data *epd = data; | |
2153 | struct extent_io_tree *tree = epd->tree; | |
2154 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
2155 | u64 delalloc_start; | |
2156 | u64 page_end = start + PAGE_CACHE_SIZE - 1; | |
2157 | u64 end; | |
2158 | u64 cur = start; | |
2159 | u64 extent_offset; | |
2160 | u64 last_byte = i_size_read(inode); | |
2161 | u64 block_start; | |
2162 | u64 iosize; | |
e6dcd2dc | 2163 | u64 unlock_start; |
d1310b2e CM |
2164 | sector_t sector; |
2165 | struct extent_map *em; | |
2166 | struct block_device *bdev; | |
2167 | int ret; | |
2168 | int nr = 0; | |
7f3c74fb | 2169 | size_t pg_offset = 0; |
d1310b2e CM |
2170 | size_t blocksize; |
2171 | loff_t i_size = i_size_read(inode); | |
2172 | unsigned long end_index = i_size >> PAGE_CACHE_SHIFT; | |
2173 | u64 nr_delalloc; | |
2174 | u64 delalloc_end; | |
c8b97818 CM |
2175 | int page_started; |
2176 | int compressed; | |
771ed689 | 2177 | unsigned long nr_written = 0; |
d1310b2e CM |
2178 | |
2179 | WARN_ON(!PageLocked(page)); | |
7f3c74fb | 2180 | pg_offset = i_size & (PAGE_CACHE_SIZE - 1); |
211c17f5 | 2181 | if (page->index > end_index || |
7f3c74fb | 2182 | (page->index == end_index && !pg_offset)) { |
39be25cd | 2183 | page->mapping->a_ops->invalidatepage(page, 0); |
d1310b2e CM |
2184 | unlock_page(page); |
2185 | return 0; | |
2186 | } | |
2187 | ||
2188 | if (page->index == end_index) { | |
2189 | char *userpage; | |
2190 | ||
d1310b2e | 2191 | userpage = kmap_atomic(page, KM_USER0); |
7f3c74fb CM |
2192 | memset(userpage + pg_offset, 0, |
2193 | PAGE_CACHE_SIZE - pg_offset); | |
d1310b2e | 2194 | kunmap_atomic(userpage, KM_USER0); |
211c17f5 | 2195 | flush_dcache_page(page); |
d1310b2e | 2196 | } |
7f3c74fb | 2197 | pg_offset = 0; |
d1310b2e CM |
2198 | |
2199 | set_page_extent_mapped(page); | |
2200 | ||
2201 | delalloc_start = start; | |
2202 | delalloc_end = 0; | |
c8b97818 | 2203 | page_started = 0; |
771ed689 CM |
2204 | if (!epd->extent_locked) { |
2205 | while(delalloc_end < page_end) { | |
2206 | nr_delalloc = find_lock_delalloc_range(inode, tree, | |
c8b97818 CM |
2207 | page, |
2208 | &delalloc_start, | |
d1310b2e CM |
2209 | &delalloc_end, |
2210 | 128 * 1024 * 1024); | |
771ed689 CM |
2211 | if (nr_delalloc == 0) { |
2212 | delalloc_start = delalloc_end + 1; | |
2213 | continue; | |
2214 | } | |
2215 | tree->ops->fill_delalloc(inode, page, delalloc_start, | |
2216 | delalloc_end, &page_started, | |
2217 | &nr_written); | |
d1310b2e | 2218 | delalloc_start = delalloc_end + 1; |
d1310b2e | 2219 | } |
c8b97818 | 2220 | |
771ed689 CM |
2221 | /* did the fill delalloc function already unlock and start |
2222 | * the IO? | |
2223 | */ | |
2224 | if (page_started) { | |
2225 | ret = 0; | |
2226 | goto update_nr_written; | |
2227 | } | |
c8b97818 | 2228 | } |
d1310b2e | 2229 | lock_extent(tree, start, page_end, GFP_NOFS); |
771ed689 | 2230 | |
e6dcd2dc | 2231 | unlock_start = start; |
d1310b2e | 2232 | |
247e743c | 2233 | if (tree->ops && tree->ops->writepage_start_hook) { |
c8b97818 CM |
2234 | ret = tree->ops->writepage_start_hook(page, start, |
2235 | page_end); | |
247e743c CM |
2236 | if (ret == -EAGAIN) { |
2237 | unlock_extent(tree, start, page_end, GFP_NOFS); | |
2238 | redirty_page_for_writepage(wbc, page); | |
2239 | unlock_page(page); | |
771ed689 CM |
2240 | ret = 0; |
2241 | goto update_nr_written; | |
247e743c CM |
2242 | } |
2243 | } | |
2244 | ||
771ed689 CM |
2245 | nr_written++; |
2246 | ||
d1310b2e CM |
2247 | end = page_end; |
2248 | if (test_range_bit(tree, start, page_end, EXTENT_DELALLOC, 0)) { | |
2249 | printk("found delalloc bits after lock_extent\n"); | |
2250 | } | |
2251 | ||
2252 | if (last_byte <= start) { | |
2253 | clear_extent_dirty(tree, start, page_end, GFP_NOFS); | |
e6dcd2dc CM |
2254 | unlock_extent(tree, start, page_end, GFP_NOFS); |
2255 | if (tree->ops && tree->ops->writepage_end_io_hook) | |
2256 | tree->ops->writepage_end_io_hook(page, start, | |
2257 | page_end, NULL, 1); | |
2258 | unlock_start = page_end + 1; | |
d1310b2e CM |
2259 | goto done; |
2260 | } | |
2261 | ||
2262 | set_extent_uptodate(tree, start, page_end, GFP_NOFS); | |
2263 | blocksize = inode->i_sb->s_blocksize; | |
2264 | ||
2265 | while (cur <= end) { | |
2266 | if (cur >= last_byte) { | |
2267 | clear_extent_dirty(tree, cur, page_end, GFP_NOFS); | |
e6dcd2dc CM |
2268 | unlock_extent(tree, unlock_start, page_end, GFP_NOFS); |
2269 | if (tree->ops && tree->ops->writepage_end_io_hook) | |
2270 | tree->ops->writepage_end_io_hook(page, cur, | |
2271 | page_end, NULL, 1); | |
2272 | unlock_start = page_end + 1; | |
d1310b2e CM |
2273 | break; |
2274 | } | |
7f3c74fb | 2275 | em = epd->get_extent(inode, page, pg_offset, cur, |
d1310b2e CM |
2276 | end - cur + 1, 1); |
2277 | if (IS_ERR(em) || !em) { | |
2278 | SetPageError(page); | |
2279 | break; | |
2280 | } | |
2281 | ||
2282 | extent_offset = cur - em->start; | |
2283 | BUG_ON(extent_map_end(em) <= cur); | |
2284 | BUG_ON(end < cur); | |
2285 | iosize = min(extent_map_end(em) - cur, end - cur + 1); | |
2286 | iosize = (iosize + blocksize - 1) & ~((u64)blocksize - 1); | |
2287 | sector = (em->block_start + extent_offset) >> 9; | |
2288 | bdev = em->bdev; | |
2289 | block_start = em->block_start; | |
c8b97818 | 2290 | compressed = test_bit(EXTENT_FLAG_COMPRESSED, &em->flags); |
d1310b2e CM |
2291 | free_extent_map(em); |
2292 | em = NULL; | |
2293 | ||
c8b97818 CM |
2294 | /* |
2295 | * compressed and inline extents are written through other | |
2296 | * paths in the FS | |
2297 | */ | |
2298 | if (compressed || block_start == EXTENT_MAP_HOLE || | |
d1310b2e CM |
2299 | block_start == EXTENT_MAP_INLINE) { |
2300 | clear_extent_dirty(tree, cur, | |
2301 | cur + iosize - 1, GFP_NOFS); | |
e6dcd2dc CM |
2302 | |
2303 | unlock_extent(tree, unlock_start, cur + iosize -1, | |
2304 | GFP_NOFS); | |
7f3c74fb | 2305 | |
c8b97818 CM |
2306 | /* |
2307 | * end_io notification does not happen here for | |
2308 | * compressed extents | |
2309 | */ | |
2310 | if (!compressed && tree->ops && | |
2311 | tree->ops->writepage_end_io_hook) | |
e6dcd2dc CM |
2312 | tree->ops->writepage_end_io_hook(page, cur, |
2313 | cur + iosize - 1, | |
2314 | NULL, 1); | |
c8b97818 CM |
2315 | else if (compressed) { |
2316 | /* we don't want to end_page_writeback on | |
2317 | * a compressed extent. this happens | |
2318 | * elsewhere | |
2319 | */ | |
2320 | nr++; | |
2321 | } | |
2322 | ||
2323 | cur += iosize; | |
7f3c74fb | 2324 | pg_offset += iosize; |
e6dcd2dc | 2325 | unlock_start = cur; |
d1310b2e CM |
2326 | continue; |
2327 | } | |
d1310b2e CM |
2328 | /* leave this out until we have a page_mkwrite call */ |
2329 | if (0 && !test_range_bit(tree, cur, cur + iosize - 1, | |
2330 | EXTENT_DIRTY, 0)) { | |
2331 | cur = cur + iosize; | |
7f3c74fb | 2332 | pg_offset += iosize; |
d1310b2e CM |
2333 | continue; |
2334 | } | |
c8b97818 | 2335 | |
d1310b2e CM |
2336 | clear_extent_dirty(tree, cur, cur + iosize - 1, GFP_NOFS); |
2337 | if (tree->ops && tree->ops->writepage_io_hook) { | |
2338 | ret = tree->ops->writepage_io_hook(page, cur, | |
2339 | cur + iosize - 1); | |
2340 | } else { | |
2341 | ret = 0; | |
2342 | } | |
1259ab75 | 2343 | if (ret) { |
d1310b2e | 2344 | SetPageError(page); |
1259ab75 | 2345 | } else { |
d1310b2e | 2346 | unsigned long max_nr = end_index + 1; |
7f3c74fb | 2347 | |
d1310b2e CM |
2348 | set_range_writeback(tree, cur, cur + iosize - 1); |
2349 | if (!PageWriteback(page)) { | |
2350 | printk("warning page %lu not writeback, " | |
2351 | "cur %llu end %llu\n", page->index, | |
2352 | (unsigned long long)cur, | |
2353 | (unsigned long long)end); | |
2354 | } | |
2355 | ||
2356 | ret = submit_extent_page(WRITE, tree, page, sector, | |
7f3c74fb | 2357 | iosize, pg_offset, bdev, |
d1310b2e | 2358 | &epd->bio, max_nr, |
c8b97818 CM |
2359 | end_bio_extent_writepage, |
2360 | 0, 0, 0); | |
d1310b2e CM |
2361 | if (ret) |
2362 | SetPageError(page); | |
2363 | } | |
2364 | cur = cur + iosize; | |
7f3c74fb | 2365 | pg_offset += iosize; |
d1310b2e CM |
2366 | nr++; |
2367 | } | |
2368 | done: | |
2369 | if (nr == 0) { | |
2370 | /* make sure the mapping tag for page dirty gets cleared */ | |
2371 | set_page_writeback(page); | |
2372 | end_page_writeback(page); | |
2373 | } | |
e6dcd2dc CM |
2374 | if (unlock_start <= page_end) |
2375 | unlock_extent(tree, unlock_start, page_end, GFP_NOFS); | |
d1310b2e | 2376 | unlock_page(page); |
771ed689 CM |
2377 | |
2378 | update_nr_written: | |
2379 | wbc->nr_to_write -= nr_written; | |
2380 | if (wbc->range_cyclic || (wbc->nr_to_write > 0 && | |
2381 | wbc->range_start == 0 && wbc->range_end == LLONG_MAX)) | |
2382 | page->mapping->writeback_index = page->index + nr_written; | |
d1310b2e CM |
2383 | return 0; |
2384 | } | |
2385 | ||
d1310b2e | 2386 | /** |
4bef0848 | 2387 | * write_cache_pages - walk the list of dirty pages of the given address space and write all of them. |
d1310b2e CM |
2388 | * @mapping: address space structure to write |
2389 | * @wbc: subtract the number of written pages from *@wbc->nr_to_write | |
2390 | * @writepage: function called for each page | |
2391 | * @data: data passed to writepage function | |
2392 | * | |
2393 | * If a page is already under I/O, write_cache_pages() skips it, even | |
2394 | * if it's dirty. This is desirable behaviour for memory-cleaning writeback, | |
2395 | * but it is INCORRECT for data-integrity system calls such as fsync(). fsync() | |
2396 | * and msync() need to guarantee that all the data which was dirty at the time | |
2397 | * the call was made get new I/O started against them. If wbc->sync_mode is | |
2398 | * WB_SYNC_ALL then we were called for data integrity and we must wait for | |
2399 | * existing IO to complete. | |
2400 | */ | |
b2950863 | 2401 | static int extent_write_cache_pages(struct extent_io_tree *tree, |
4bef0848 CM |
2402 | struct address_space *mapping, |
2403 | struct writeback_control *wbc, | |
d2c3f4f6 CM |
2404 | writepage_t writepage, void *data, |
2405 | void (*flush_fn)(void *)) | |
d1310b2e CM |
2406 | { |
2407 | struct backing_dev_info *bdi = mapping->backing_dev_info; | |
2408 | int ret = 0; | |
2409 | int done = 0; | |
2410 | struct pagevec pvec; | |
2411 | int nr_pages; | |
2412 | pgoff_t index; | |
2413 | pgoff_t end; /* Inclusive */ | |
2414 | int scanned = 0; | |
2415 | int range_whole = 0; | |
2416 | ||
2417 | if (wbc->nonblocking && bdi_write_congested(bdi)) { | |
2418 | wbc->encountered_congestion = 1; | |
2419 | return 0; | |
2420 | } | |
2421 | ||
2422 | pagevec_init(&pvec, 0); | |
2423 | if (wbc->range_cyclic) { | |
2424 | index = mapping->writeback_index; /* Start from prev offset */ | |
2425 | end = -1; | |
2426 | } else { | |
2427 | index = wbc->range_start >> PAGE_CACHE_SHIFT; | |
2428 | end = wbc->range_end >> PAGE_CACHE_SHIFT; | |
2429 | if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) | |
2430 | range_whole = 1; | |
2431 | scanned = 1; | |
2432 | } | |
2433 | retry: | |
2434 | while (!done && (index <= end) && | |
2435 | (nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, | |
2436 | PAGECACHE_TAG_DIRTY, | |
2437 | min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1))) { | |
2438 | unsigned i; | |
2439 | ||
2440 | scanned = 1; | |
2441 | for (i = 0; i < nr_pages; i++) { | |
2442 | struct page *page = pvec.pages[i]; | |
2443 | ||
2444 | /* | |
2445 | * At this point we hold neither mapping->tree_lock nor | |
2446 | * lock on the page itself: the page may be truncated or | |
2447 | * invalidated (changing page->mapping to NULL), or even | |
2448 | * swizzled back from swapper_space to tmpfs file | |
2449 | * mapping | |
2450 | */ | |
4bef0848 CM |
2451 | if (tree->ops && tree->ops->write_cache_pages_lock_hook) |
2452 | tree->ops->write_cache_pages_lock_hook(page); | |
2453 | else | |
2454 | lock_page(page); | |
d1310b2e CM |
2455 | |
2456 | if (unlikely(page->mapping != mapping)) { | |
2457 | unlock_page(page); | |
2458 | continue; | |
2459 | } | |
2460 | ||
2461 | if (!wbc->range_cyclic && page->index > end) { | |
2462 | done = 1; | |
2463 | unlock_page(page); | |
2464 | continue; | |
2465 | } | |
2466 | ||
d2c3f4f6 | 2467 | if (wbc->sync_mode != WB_SYNC_NONE) { |
0e6bd956 CM |
2468 | if (PageWriteback(page)) |
2469 | flush_fn(data); | |
d1310b2e | 2470 | wait_on_page_writeback(page); |
d2c3f4f6 | 2471 | } |
d1310b2e CM |
2472 | |
2473 | if (PageWriteback(page) || | |
2474 | !clear_page_dirty_for_io(page)) { | |
2475 | unlock_page(page); | |
2476 | continue; | |
2477 | } | |
2478 | ||
2479 | ret = (*writepage)(page, wbc, data); | |
2480 | ||
2481 | if (unlikely(ret == AOP_WRITEPAGE_ACTIVATE)) { | |
2482 | unlock_page(page); | |
2483 | ret = 0; | |
2484 | } | |
771ed689 | 2485 | if (ret || wbc->nr_to_write <= 0) |
d1310b2e CM |
2486 | done = 1; |
2487 | if (wbc->nonblocking && bdi_write_congested(bdi)) { | |
2488 | wbc->encountered_congestion = 1; | |
2489 | done = 1; | |
2490 | } | |
2491 | } | |
2492 | pagevec_release(&pvec); | |
2493 | cond_resched(); | |
2494 | } | |
2495 | if (!scanned && !done) { | |
2496 | /* | |
2497 | * We hit the last page and there is more work to be done: wrap | |
2498 | * back to the start of the file | |
2499 | */ | |
2500 | scanned = 1; | |
2501 | index = 0; | |
2502 | goto retry; | |
2503 | } | |
d1310b2e CM |
2504 | return ret; |
2505 | } | |
d1310b2e | 2506 | |
d2c3f4f6 CM |
2507 | static noinline void flush_write_bio(void *data) |
2508 | { | |
2509 | struct extent_page_data *epd = data; | |
2510 | if (epd->bio) { | |
2511 | submit_one_bio(WRITE, epd->bio, 0, 0); | |
2512 | epd->bio = NULL; | |
2513 | } | |
2514 | } | |
2515 | ||
d1310b2e CM |
2516 | int extent_write_full_page(struct extent_io_tree *tree, struct page *page, |
2517 | get_extent_t *get_extent, | |
2518 | struct writeback_control *wbc) | |
2519 | { | |
2520 | int ret; | |
2521 | struct address_space *mapping = page->mapping; | |
2522 | struct extent_page_data epd = { | |
2523 | .bio = NULL, | |
2524 | .tree = tree, | |
2525 | .get_extent = get_extent, | |
771ed689 | 2526 | .extent_locked = 0, |
d1310b2e CM |
2527 | }; |
2528 | struct writeback_control wbc_writepages = { | |
2529 | .bdi = wbc->bdi, | |
2530 | .sync_mode = WB_SYNC_NONE, | |
2531 | .older_than_this = NULL, | |
2532 | .nr_to_write = 64, | |
2533 | .range_start = page_offset(page) + PAGE_CACHE_SIZE, | |
2534 | .range_end = (loff_t)-1, | |
2535 | }; | |
2536 | ||
2537 | ||
2538 | ret = __extent_writepage(page, wbc, &epd); | |
2539 | ||
4bef0848 | 2540 | extent_write_cache_pages(tree, mapping, &wbc_writepages, |
d2c3f4f6 | 2541 | __extent_writepage, &epd, flush_write_bio); |
d1310b2e | 2542 | if (epd.bio) { |
c8b97818 | 2543 | submit_one_bio(WRITE, epd.bio, 0, 0); |
d1310b2e CM |
2544 | } |
2545 | return ret; | |
2546 | } | |
2547 | EXPORT_SYMBOL(extent_write_full_page); | |
2548 | ||
771ed689 CM |
2549 | int extent_write_locked_range(struct extent_io_tree *tree, struct inode *inode, |
2550 | u64 start, u64 end, get_extent_t *get_extent, | |
2551 | int mode) | |
2552 | { | |
2553 | int ret = 0; | |
2554 | struct address_space *mapping = inode->i_mapping; | |
2555 | struct page *page; | |
2556 | unsigned long nr_pages = (end - start + PAGE_CACHE_SIZE) >> | |
2557 | PAGE_CACHE_SHIFT; | |
2558 | ||
2559 | struct extent_page_data epd = { | |
2560 | .bio = NULL, | |
2561 | .tree = tree, | |
2562 | .get_extent = get_extent, | |
2563 | .extent_locked = 1, | |
2564 | }; | |
2565 | struct writeback_control wbc_writepages = { | |
2566 | .bdi = inode->i_mapping->backing_dev_info, | |
2567 | .sync_mode = mode, | |
2568 | .older_than_this = NULL, | |
2569 | .nr_to_write = nr_pages * 2, | |
2570 | .range_start = start, | |
2571 | .range_end = end + 1, | |
2572 | }; | |
2573 | ||
2574 | while(start <= end) { | |
2575 | page = find_get_page(mapping, start >> PAGE_CACHE_SHIFT); | |
2576 | if (clear_page_dirty_for_io(page)) | |
2577 | ret = __extent_writepage(page, &wbc_writepages, &epd); | |
2578 | else { | |
2579 | if (tree->ops && tree->ops->writepage_end_io_hook) | |
2580 | tree->ops->writepage_end_io_hook(page, start, | |
2581 | start + PAGE_CACHE_SIZE - 1, | |
2582 | NULL, 1); | |
2583 | unlock_page(page); | |
2584 | } | |
2585 | page_cache_release(page); | |
2586 | start += PAGE_CACHE_SIZE; | |
2587 | } | |
2588 | ||
2589 | if (epd.bio) | |
2590 | submit_one_bio(WRITE, epd.bio, 0, 0); | |
2591 | return ret; | |
2592 | } | |
2593 | EXPORT_SYMBOL(extent_write_locked_range); | |
2594 | ||
d1310b2e CM |
2595 | |
2596 | int extent_writepages(struct extent_io_tree *tree, | |
2597 | struct address_space *mapping, | |
2598 | get_extent_t *get_extent, | |
2599 | struct writeback_control *wbc) | |
2600 | { | |
2601 | int ret = 0; | |
2602 | struct extent_page_data epd = { | |
2603 | .bio = NULL, | |
2604 | .tree = tree, | |
2605 | .get_extent = get_extent, | |
771ed689 | 2606 | .extent_locked = 0, |
d1310b2e CM |
2607 | }; |
2608 | ||
4bef0848 | 2609 | ret = extent_write_cache_pages(tree, mapping, wbc, |
d2c3f4f6 CM |
2610 | __extent_writepage, &epd, |
2611 | flush_write_bio); | |
d1310b2e | 2612 | if (epd.bio) { |
c8b97818 | 2613 | submit_one_bio(WRITE, epd.bio, 0, 0); |
d1310b2e CM |
2614 | } |
2615 | return ret; | |
2616 | } | |
2617 | EXPORT_SYMBOL(extent_writepages); | |
2618 | ||
2619 | int extent_readpages(struct extent_io_tree *tree, | |
2620 | struct address_space *mapping, | |
2621 | struct list_head *pages, unsigned nr_pages, | |
2622 | get_extent_t get_extent) | |
2623 | { | |
2624 | struct bio *bio = NULL; | |
2625 | unsigned page_idx; | |
2626 | struct pagevec pvec; | |
c8b97818 | 2627 | unsigned long bio_flags = 0; |
d1310b2e CM |
2628 | |
2629 | pagevec_init(&pvec, 0); | |
2630 | for (page_idx = 0; page_idx < nr_pages; page_idx++) { | |
2631 | struct page *page = list_entry(pages->prev, struct page, lru); | |
2632 | ||
2633 | prefetchw(&page->flags); | |
2634 | list_del(&page->lru); | |
2635 | /* | |
2636 | * what we want to do here is call add_to_page_cache_lru, | |
2637 | * but that isn't exported, so we reproduce it here | |
2638 | */ | |
2639 | if (!add_to_page_cache(page, mapping, | |
2640 | page->index, GFP_KERNEL)) { | |
2641 | ||
2642 | /* open coding of lru_cache_add, also not exported */ | |
2643 | page_cache_get(page); | |
2644 | if (!pagevec_add(&pvec, page)) | |
15916de8 | 2645 | __pagevec_lru_add_file(&pvec); |
f188591e | 2646 | __extent_read_full_page(tree, page, get_extent, |
c8b97818 | 2647 | &bio, 0, &bio_flags); |
d1310b2e CM |
2648 | } |
2649 | page_cache_release(page); | |
2650 | } | |
2651 | if (pagevec_count(&pvec)) | |
15916de8 | 2652 | __pagevec_lru_add_file(&pvec); |
d1310b2e CM |
2653 | BUG_ON(!list_empty(pages)); |
2654 | if (bio) | |
c8b97818 | 2655 | submit_one_bio(READ, bio, 0, bio_flags); |
d1310b2e CM |
2656 | return 0; |
2657 | } | |
2658 | EXPORT_SYMBOL(extent_readpages); | |
2659 | ||
2660 | /* | |
2661 | * basic invalidatepage code, this waits on any locked or writeback | |
2662 | * ranges corresponding to the page, and then deletes any extent state | |
2663 | * records from the tree | |
2664 | */ | |
2665 | int extent_invalidatepage(struct extent_io_tree *tree, | |
2666 | struct page *page, unsigned long offset) | |
2667 | { | |
2668 | u64 start = ((u64)page->index << PAGE_CACHE_SHIFT); | |
2669 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
2670 | size_t blocksize = page->mapping->host->i_sb->s_blocksize; | |
2671 | ||
2672 | start += (offset + blocksize -1) & ~(blocksize - 1); | |
2673 | if (start > end) | |
2674 | return 0; | |
2675 | ||
2676 | lock_extent(tree, start, end, GFP_NOFS); | |
2677 | wait_on_extent_writeback(tree, start, end); | |
2678 | clear_extent_bit(tree, start, end, | |
2679 | EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC, | |
2680 | 1, 1, GFP_NOFS); | |
2681 | return 0; | |
2682 | } | |
2683 | EXPORT_SYMBOL(extent_invalidatepage); | |
2684 | ||
2685 | /* | |
2686 | * simple commit_write call, set_range_dirty is used to mark both | |
2687 | * the pages and the extent records as dirty | |
2688 | */ | |
2689 | int extent_commit_write(struct extent_io_tree *tree, | |
2690 | struct inode *inode, struct page *page, | |
2691 | unsigned from, unsigned to) | |
2692 | { | |
2693 | loff_t pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to; | |
2694 | ||
2695 | set_page_extent_mapped(page); | |
2696 | set_page_dirty(page); | |
2697 | ||
2698 | if (pos > inode->i_size) { | |
2699 | i_size_write(inode, pos); | |
2700 | mark_inode_dirty(inode); | |
2701 | } | |
2702 | return 0; | |
2703 | } | |
2704 | EXPORT_SYMBOL(extent_commit_write); | |
2705 | ||
2706 | int extent_prepare_write(struct extent_io_tree *tree, | |
2707 | struct inode *inode, struct page *page, | |
2708 | unsigned from, unsigned to, get_extent_t *get_extent) | |
2709 | { | |
2710 | u64 page_start = (u64)page->index << PAGE_CACHE_SHIFT; | |
2711 | u64 page_end = page_start + PAGE_CACHE_SIZE - 1; | |
2712 | u64 block_start; | |
2713 | u64 orig_block_start; | |
2714 | u64 block_end; | |
2715 | u64 cur_end; | |
2716 | struct extent_map *em; | |
2717 | unsigned blocksize = 1 << inode->i_blkbits; | |
2718 | size_t page_offset = 0; | |
2719 | size_t block_off_start; | |
2720 | size_t block_off_end; | |
2721 | int err = 0; | |
2722 | int iocount = 0; | |
2723 | int ret = 0; | |
2724 | int isnew; | |
2725 | ||
2726 | set_page_extent_mapped(page); | |
2727 | ||
2728 | block_start = (page_start + from) & ~((u64)blocksize - 1); | |
2729 | block_end = (page_start + to - 1) | (blocksize - 1); | |
2730 | orig_block_start = block_start; | |
2731 | ||
2732 | lock_extent(tree, page_start, page_end, GFP_NOFS); | |
2733 | while(block_start <= block_end) { | |
2734 | em = get_extent(inode, page, page_offset, block_start, | |
2735 | block_end - block_start + 1, 1); | |
2736 | if (IS_ERR(em) || !em) { | |
2737 | goto err; | |
2738 | } | |
2739 | cur_end = min(block_end, extent_map_end(em) - 1); | |
2740 | block_off_start = block_start & (PAGE_CACHE_SIZE - 1); | |
2741 | block_off_end = block_off_start + blocksize; | |
2742 | isnew = clear_extent_new(tree, block_start, cur_end, GFP_NOFS); | |
2743 | ||
2744 | if (!PageUptodate(page) && isnew && | |
2745 | (block_off_end > to || block_off_start < from)) { | |
2746 | void *kaddr; | |
2747 | ||
2748 | kaddr = kmap_atomic(page, KM_USER0); | |
2749 | if (block_off_end > to) | |
2750 | memset(kaddr + to, 0, block_off_end - to); | |
2751 | if (block_off_start < from) | |
2752 | memset(kaddr + block_off_start, 0, | |
2753 | from - block_off_start); | |
2754 | flush_dcache_page(page); | |
2755 | kunmap_atomic(kaddr, KM_USER0); | |
2756 | } | |
2757 | if ((em->block_start != EXTENT_MAP_HOLE && | |
2758 | em->block_start != EXTENT_MAP_INLINE) && | |
2759 | !isnew && !PageUptodate(page) && | |
2760 | (block_off_end > to || block_off_start < from) && | |
2761 | !test_range_bit(tree, block_start, cur_end, | |
2762 | EXTENT_UPTODATE, 1)) { | |
2763 | u64 sector; | |
2764 | u64 extent_offset = block_start - em->start; | |
2765 | size_t iosize; | |
2766 | sector = (em->block_start + extent_offset) >> 9; | |
2767 | iosize = (cur_end - block_start + blocksize) & | |
2768 | ~((u64)blocksize - 1); | |
2769 | /* | |
2770 | * we've already got the extent locked, but we | |
2771 | * need to split the state such that our end_bio | |
2772 | * handler can clear the lock. | |
2773 | */ | |
2774 | set_extent_bit(tree, block_start, | |
2775 | block_start + iosize - 1, | |
2776 | EXTENT_LOCKED, 0, NULL, GFP_NOFS); | |
2777 | ret = submit_extent_page(READ, tree, page, | |
2778 | sector, iosize, page_offset, em->bdev, | |
2779 | NULL, 1, | |
c8b97818 CM |
2780 | end_bio_extent_preparewrite, 0, |
2781 | 0, 0); | |
d1310b2e CM |
2782 | iocount++; |
2783 | block_start = block_start + iosize; | |
2784 | } else { | |
2785 | set_extent_uptodate(tree, block_start, cur_end, | |
2786 | GFP_NOFS); | |
2787 | unlock_extent(tree, block_start, cur_end, GFP_NOFS); | |
2788 | block_start = cur_end + 1; | |
2789 | } | |
2790 | page_offset = block_start & (PAGE_CACHE_SIZE - 1); | |
2791 | free_extent_map(em); | |
2792 | } | |
2793 | if (iocount) { | |
2794 | wait_extent_bit(tree, orig_block_start, | |
2795 | block_end, EXTENT_LOCKED); | |
2796 | } | |
2797 | check_page_uptodate(tree, page); | |
2798 | err: | |
2799 | /* FIXME, zero out newly allocated blocks on error */ | |
2800 | return err; | |
2801 | } | |
2802 | EXPORT_SYMBOL(extent_prepare_write); | |
2803 | ||
7b13b7b1 CM |
2804 | /* |
2805 | * a helper for releasepage, this tests for areas of the page that | |
2806 | * are locked or under IO and drops the related state bits if it is safe | |
2807 | * to drop the page. | |
2808 | */ | |
2809 | int try_release_extent_state(struct extent_map_tree *map, | |
2810 | struct extent_io_tree *tree, struct page *page, | |
2811 | gfp_t mask) | |
2812 | { | |
2813 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
2814 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
2815 | int ret = 1; | |
2816 | ||
211f90e6 CM |
2817 | if (test_range_bit(tree, start, end, |
2818 | EXTENT_IOBITS | EXTENT_ORDERED, 0)) | |
7b13b7b1 CM |
2819 | ret = 0; |
2820 | else { | |
2821 | if ((mask & GFP_NOFS) == GFP_NOFS) | |
2822 | mask = GFP_NOFS; | |
2823 | clear_extent_bit(tree, start, end, EXTENT_UPTODATE, | |
2824 | 1, 1, mask); | |
2825 | } | |
2826 | return ret; | |
2827 | } | |
2828 | EXPORT_SYMBOL(try_release_extent_state); | |
2829 | ||
d1310b2e CM |
2830 | /* |
2831 | * a helper for releasepage. As long as there are no locked extents | |
2832 | * in the range corresponding to the page, both state records and extent | |
2833 | * map records are removed | |
2834 | */ | |
2835 | int try_release_extent_mapping(struct extent_map_tree *map, | |
70dec807 CM |
2836 | struct extent_io_tree *tree, struct page *page, |
2837 | gfp_t mask) | |
d1310b2e CM |
2838 | { |
2839 | struct extent_map *em; | |
2840 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
2841 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
7b13b7b1 | 2842 | |
70dec807 CM |
2843 | if ((mask & __GFP_WAIT) && |
2844 | page->mapping->host->i_size > 16 * 1024 * 1024) { | |
39b5637f | 2845 | u64 len; |
70dec807 | 2846 | while (start <= end) { |
39b5637f | 2847 | len = end - start + 1; |
70dec807 | 2848 | spin_lock(&map->lock); |
39b5637f | 2849 | em = lookup_extent_mapping(map, start, len); |
70dec807 CM |
2850 | if (!em || IS_ERR(em)) { |
2851 | spin_unlock(&map->lock); | |
2852 | break; | |
2853 | } | |
7f3c74fb CM |
2854 | if (test_bit(EXTENT_FLAG_PINNED, &em->flags) || |
2855 | em->start != start) { | |
70dec807 CM |
2856 | spin_unlock(&map->lock); |
2857 | free_extent_map(em); | |
2858 | break; | |
2859 | } | |
2860 | if (!test_range_bit(tree, em->start, | |
2861 | extent_map_end(em) - 1, | |
c8b97818 CM |
2862 | EXTENT_LOCKED | EXTENT_WRITEBACK | |
2863 | EXTENT_ORDERED, | |
2864 | 0)) { | |
70dec807 CM |
2865 | remove_extent_mapping(map, em); |
2866 | /* once for the rb tree */ | |
2867 | free_extent_map(em); | |
2868 | } | |
2869 | start = extent_map_end(em); | |
d1310b2e | 2870 | spin_unlock(&map->lock); |
70dec807 CM |
2871 | |
2872 | /* once for us */ | |
d1310b2e CM |
2873 | free_extent_map(em); |
2874 | } | |
d1310b2e | 2875 | } |
7b13b7b1 | 2876 | return try_release_extent_state(map, tree, page, mask); |
d1310b2e CM |
2877 | } |
2878 | EXPORT_SYMBOL(try_release_extent_mapping); | |
2879 | ||
2880 | sector_t extent_bmap(struct address_space *mapping, sector_t iblock, | |
2881 | get_extent_t *get_extent) | |
2882 | { | |
2883 | struct inode *inode = mapping->host; | |
2884 | u64 start = iblock << inode->i_blkbits; | |
2885 | sector_t sector = 0; | |
d899e052 | 2886 | size_t blksize = (1 << inode->i_blkbits); |
d1310b2e CM |
2887 | struct extent_map *em; |
2888 | ||
d899e052 YZ |
2889 | lock_extent(&BTRFS_I(inode)->io_tree, start, start + blksize - 1, |
2890 | GFP_NOFS); | |
2891 | em = get_extent(inode, NULL, 0, start, blksize, 0); | |
2892 | unlock_extent(&BTRFS_I(inode)->io_tree, start, start + blksize - 1, | |
2893 | GFP_NOFS); | |
d1310b2e CM |
2894 | if (!em || IS_ERR(em)) |
2895 | return 0; | |
2896 | ||
d899e052 | 2897 | if (em->block_start > EXTENT_MAP_LAST_BYTE) |
d1310b2e CM |
2898 | goto out; |
2899 | ||
2900 | sector = (em->block_start + start - em->start) >> inode->i_blkbits; | |
d1310b2e CM |
2901 | out: |
2902 | free_extent_map(em); | |
2903 | return sector; | |
2904 | } | |
2905 | ||
d1310b2e CM |
2906 | static inline struct page *extent_buffer_page(struct extent_buffer *eb, |
2907 | unsigned long i) | |
2908 | { | |
2909 | struct page *p; | |
2910 | struct address_space *mapping; | |
2911 | ||
2912 | if (i == 0) | |
2913 | return eb->first_page; | |
2914 | i += eb->start >> PAGE_CACHE_SHIFT; | |
2915 | mapping = eb->first_page->mapping; | |
33958dc6 CM |
2916 | if (!mapping) |
2917 | return NULL; | |
0ee0fda0 SW |
2918 | |
2919 | /* | |
2920 | * extent_buffer_page is only called after pinning the page | |
2921 | * by increasing the reference count. So we know the page must | |
2922 | * be in the radix tree. | |
2923 | */ | |
0ee0fda0 | 2924 | rcu_read_lock(); |
d1310b2e | 2925 | p = radix_tree_lookup(&mapping->page_tree, i); |
0ee0fda0 | 2926 | rcu_read_unlock(); |
2b1f55b0 | 2927 | |
d1310b2e CM |
2928 | return p; |
2929 | } | |
2930 | ||
6af118ce | 2931 | static inline unsigned long num_extent_pages(u64 start, u64 len) |
728131d8 | 2932 | { |
6af118ce CM |
2933 | return ((start + len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT) - |
2934 | (start >> PAGE_CACHE_SHIFT); | |
728131d8 CM |
2935 | } |
2936 | ||
d1310b2e CM |
2937 | static struct extent_buffer *__alloc_extent_buffer(struct extent_io_tree *tree, |
2938 | u64 start, | |
2939 | unsigned long len, | |
2940 | gfp_t mask) | |
2941 | { | |
2942 | struct extent_buffer *eb = NULL; | |
4bef0848 | 2943 | #ifdef LEAK_DEBUG |
2d2ae547 | 2944 | unsigned long flags; |
4bef0848 | 2945 | #endif |
d1310b2e | 2946 | |
d1310b2e | 2947 | eb = kmem_cache_zalloc(extent_buffer_cache, mask); |
d1310b2e CM |
2948 | eb->start = start; |
2949 | eb->len = len; | |
a61e6f29 | 2950 | mutex_init(&eb->mutex); |
4bef0848 | 2951 | #ifdef LEAK_DEBUG |
2d2ae547 CM |
2952 | spin_lock_irqsave(&leak_lock, flags); |
2953 | list_add(&eb->leak_list, &buffers); | |
2954 | spin_unlock_irqrestore(&leak_lock, flags); | |
4bef0848 | 2955 | #endif |
d1310b2e CM |
2956 | atomic_set(&eb->refs, 1); |
2957 | ||
2958 | return eb; | |
2959 | } | |
2960 | ||
2961 | static void __free_extent_buffer(struct extent_buffer *eb) | |
2962 | { | |
4bef0848 | 2963 | #ifdef LEAK_DEBUG |
2d2ae547 CM |
2964 | unsigned long flags; |
2965 | spin_lock_irqsave(&leak_lock, flags); | |
2966 | list_del(&eb->leak_list); | |
2967 | spin_unlock_irqrestore(&leak_lock, flags); | |
4bef0848 | 2968 | #endif |
d1310b2e CM |
2969 | kmem_cache_free(extent_buffer_cache, eb); |
2970 | } | |
2971 | ||
2972 | struct extent_buffer *alloc_extent_buffer(struct extent_io_tree *tree, | |
2973 | u64 start, unsigned long len, | |
2974 | struct page *page0, | |
2975 | gfp_t mask) | |
2976 | { | |
2977 | unsigned long num_pages = num_extent_pages(start, len); | |
2978 | unsigned long i; | |
2979 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
2980 | struct extent_buffer *eb; | |
6af118ce | 2981 | struct extent_buffer *exists = NULL; |
d1310b2e CM |
2982 | struct page *p; |
2983 | struct address_space *mapping = tree->mapping; | |
2984 | int uptodate = 1; | |
2985 | ||
6af118ce CM |
2986 | spin_lock(&tree->buffer_lock); |
2987 | eb = buffer_search(tree, start); | |
2988 | if (eb) { | |
2989 | atomic_inc(&eb->refs); | |
2990 | spin_unlock(&tree->buffer_lock); | |
0f9dd46c | 2991 | mark_page_accessed(eb->first_page); |
6af118ce CM |
2992 | return eb; |
2993 | } | |
2994 | spin_unlock(&tree->buffer_lock); | |
2995 | ||
d1310b2e | 2996 | eb = __alloc_extent_buffer(tree, start, len, mask); |
2b114d1d | 2997 | if (!eb) |
d1310b2e CM |
2998 | return NULL; |
2999 | ||
d1310b2e CM |
3000 | if (page0) { |
3001 | eb->first_page = page0; | |
3002 | i = 1; | |
3003 | index++; | |
3004 | page_cache_get(page0); | |
3005 | mark_page_accessed(page0); | |
3006 | set_page_extent_mapped(page0); | |
d1310b2e | 3007 | set_page_extent_head(page0, len); |
f188591e | 3008 | uptodate = PageUptodate(page0); |
d1310b2e CM |
3009 | } else { |
3010 | i = 0; | |
3011 | } | |
3012 | for (; i < num_pages; i++, index++) { | |
3013 | p = find_or_create_page(mapping, index, mask | __GFP_HIGHMEM); | |
3014 | if (!p) { | |
3015 | WARN_ON(1); | |
6af118ce | 3016 | goto free_eb; |
d1310b2e CM |
3017 | } |
3018 | set_page_extent_mapped(p); | |
3019 | mark_page_accessed(p); | |
3020 | if (i == 0) { | |
3021 | eb->first_page = p; | |
3022 | set_page_extent_head(p, len); | |
3023 | } else { | |
3024 | set_page_private(p, EXTENT_PAGE_PRIVATE); | |
3025 | } | |
3026 | if (!PageUptodate(p)) | |
3027 | uptodate = 0; | |
3028 | unlock_page(p); | |
3029 | } | |
3030 | if (uptodate) | |
3031 | eb->flags |= EXTENT_UPTODATE; | |
3032 | eb->flags |= EXTENT_BUFFER_FILLED; | |
3033 | ||
6af118ce CM |
3034 | spin_lock(&tree->buffer_lock); |
3035 | exists = buffer_tree_insert(tree, start, &eb->rb_node); | |
3036 | if (exists) { | |
3037 | /* add one reference for the caller */ | |
3038 | atomic_inc(&exists->refs); | |
3039 | spin_unlock(&tree->buffer_lock); | |
3040 | goto free_eb; | |
3041 | } | |
3042 | spin_unlock(&tree->buffer_lock); | |
3043 | ||
3044 | /* add one reference for the tree */ | |
3045 | atomic_inc(&eb->refs); | |
d1310b2e CM |
3046 | return eb; |
3047 | ||
6af118ce | 3048 | free_eb: |
d1310b2e | 3049 | if (!atomic_dec_and_test(&eb->refs)) |
6af118ce CM |
3050 | return exists; |
3051 | for (index = 1; index < i; index++) | |
d1310b2e | 3052 | page_cache_release(extent_buffer_page(eb, index)); |
6af118ce | 3053 | page_cache_release(extent_buffer_page(eb, 0)); |
d1310b2e | 3054 | __free_extent_buffer(eb); |
6af118ce | 3055 | return exists; |
d1310b2e CM |
3056 | } |
3057 | EXPORT_SYMBOL(alloc_extent_buffer); | |
3058 | ||
3059 | struct extent_buffer *find_extent_buffer(struct extent_io_tree *tree, | |
3060 | u64 start, unsigned long len, | |
3061 | gfp_t mask) | |
3062 | { | |
d1310b2e | 3063 | struct extent_buffer *eb; |
d1310b2e | 3064 | |
6af118ce CM |
3065 | spin_lock(&tree->buffer_lock); |
3066 | eb = buffer_search(tree, start); | |
3067 | if (eb) | |
3068 | atomic_inc(&eb->refs); | |
3069 | spin_unlock(&tree->buffer_lock); | |
d1310b2e | 3070 | |
0f9dd46c JB |
3071 | if (eb) |
3072 | mark_page_accessed(eb->first_page); | |
3073 | ||
d1310b2e | 3074 | return eb; |
d1310b2e CM |
3075 | } |
3076 | EXPORT_SYMBOL(find_extent_buffer); | |
3077 | ||
3078 | void free_extent_buffer(struct extent_buffer *eb) | |
3079 | { | |
d1310b2e CM |
3080 | if (!eb) |
3081 | return; | |
3082 | ||
3083 | if (!atomic_dec_and_test(&eb->refs)) | |
3084 | return; | |
3085 | ||
6af118ce | 3086 | WARN_ON(1); |
d1310b2e CM |
3087 | } |
3088 | EXPORT_SYMBOL(free_extent_buffer); | |
3089 | ||
3090 | int clear_extent_buffer_dirty(struct extent_io_tree *tree, | |
3091 | struct extent_buffer *eb) | |
3092 | { | |
3093 | int set; | |
3094 | unsigned long i; | |
3095 | unsigned long num_pages; | |
3096 | struct page *page; | |
3097 | ||
3098 | u64 start = eb->start; | |
3099 | u64 end = start + eb->len - 1; | |
3100 | ||
3101 | set = clear_extent_dirty(tree, start, end, GFP_NOFS); | |
3102 | num_pages = num_extent_pages(eb->start, eb->len); | |
3103 | ||
3104 | for (i = 0; i < num_pages; i++) { | |
3105 | page = extent_buffer_page(eb, i); | |
d2c3f4f6 CM |
3106 | if (!set && !PageDirty(page)) |
3107 | continue; | |
3108 | ||
a61e6f29 | 3109 | lock_page(page); |
d1310b2e CM |
3110 | if (i == 0) |
3111 | set_page_extent_head(page, eb->len); | |
3112 | else | |
3113 | set_page_private(page, EXTENT_PAGE_PRIVATE); | |
3114 | ||
3115 | /* | |
3116 | * if we're on the last page or the first page and the | |
3117 | * block isn't aligned on a page boundary, do extra checks | |
3118 | * to make sure we don't clean page that is partially dirty | |
3119 | */ | |
3120 | if ((i == 0 && (eb->start & (PAGE_CACHE_SIZE - 1))) || | |
3121 | ((i == num_pages - 1) && | |
3122 | ((eb->start + eb->len) & (PAGE_CACHE_SIZE - 1)))) { | |
3123 | start = (u64)page->index << PAGE_CACHE_SHIFT; | |
3124 | end = start + PAGE_CACHE_SIZE - 1; | |
3125 | if (test_range_bit(tree, start, end, | |
3126 | EXTENT_DIRTY, 0)) { | |
a61e6f29 | 3127 | unlock_page(page); |
d1310b2e CM |
3128 | continue; |
3129 | } | |
3130 | } | |
3131 | clear_page_dirty_for_io(page); | |
0ee0fda0 | 3132 | spin_lock_irq(&page->mapping->tree_lock); |
d1310b2e CM |
3133 | if (!PageDirty(page)) { |
3134 | radix_tree_tag_clear(&page->mapping->page_tree, | |
3135 | page_index(page), | |
3136 | PAGECACHE_TAG_DIRTY); | |
3137 | } | |
0ee0fda0 | 3138 | spin_unlock_irq(&page->mapping->tree_lock); |
a61e6f29 | 3139 | unlock_page(page); |
d1310b2e CM |
3140 | } |
3141 | return 0; | |
3142 | } | |
3143 | EXPORT_SYMBOL(clear_extent_buffer_dirty); | |
3144 | ||
3145 | int wait_on_extent_buffer_writeback(struct extent_io_tree *tree, | |
3146 | struct extent_buffer *eb) | |
3147 | { | |
3148 | return wait_on_extent_writeback(tree, eb->start, | |
3149 | eb->start + eb->len - 1); | |
3150 | } | |
3151 | EXPORT_SYMBOL(wait_on_extent_buffer_writeback); | |
3152 | ||
3153 | int set_extent_buffer_dirty(struct extent_io_tree *tree, | |
3154 | struct extent_buffer *eb) | |
3155 | { | |
3156 | unsigned long i; | |
3157 | unsigned long num_pages; | |
3158 | ||
3159 | num_pages = num_extent_pages(eb->start, eb->len); | |
3160 | for (i = 0; i < num_pages; i++) { | |
3161 | struct page *page = extent_buffer_page(eb, i); | |
3162 | /* writepage may need to do something special for the | |
3163 | * first page, we have to make sure page->private is | |
3164 | * properly set. releasepage may drop page->private | |
3165 | * on us if the page isn't already dirty. | |
3166 | */ | |
a1b32a59 | 3167 | lock_page(page); |
d1310b2e | 3168 | if (i == 0) { |
d1310b2e CM |
3169 | set_page_extent_head(page, eb->len); |
3170 | } else if (PagePrivate(page) && | |
3171 | page->private != EXTENT_PAGE_PRIVATE) { | |
d1310b2e | 3172 | set_page_extent_mapped(page); |
d1310b2e CM |
3173 | } |
3174 | __set_page_dirty_nobuffers(extent_buffer_page(eb, i)); | |
a1b32a59 CM |
3175 | set_extent_dirty(tree, page_offset(page), |
3176 | page_offset(page) + PAGE_CACHE_SIZE -1, | |
3177 | GFP_NOFS); | |
3178 | unlock_page(page); | |
d1310b2e | 3179 | } |
a1b32a59 | 3180 | return 0; |
d1310b2e CM |
3181 | } |
3182 | EXPORT_SYMBOL(set_extent_buffer_dirty); | |
3183 | ||
1259ab75 CM |
3184 | int clear_extent_buffer_uptodate(struct extent_io_tree *tree, |
3185 | struct extent_buffer *eb) | |
3186 | { | |
3187 | unsigned long i; | |
3188 | struct page *page; | |
3189 | unsigned long num_pages; | |
3190 | ||
3191 | num_pages = num_extent_pages(eb->start, eb->len); | |
3192 | eb->flags &= ~EXTENT_UPTODATE; | |
3193 | ||
3194 | clear_extent_uptodate(tree, eb->start, eb->start + eb->len - 1, | |
3195 | GFP_NOFS); | |
3196 | for (i = 0; i < num_pages; i++) { | |
3197 | page = extent_buffer_page(eb, i); | |
33958dc6 CM |
3198 | if (page) |
3199 | ClearPageUptodate(page); | |
1259ab75 CM |
3200 | } |
3201 | return 0; | |
3202 | } | |
3203 | ||
d1310b2e CM |
3204 | int set_extent_buffer_uptodate(struct extent_io_tree *tree, |
3205 | struct extent_buffer *eb) | |
3206 | { | |
3207 | unsigned long i; | |
3208 | struct page *page; | |
3209 | unsigned long num_pages; | |
3210 | ||
3211 | num_pages = num_extent_pages(eb->start, eb->len); | |
3212 | ||
3213 | set_extent_uptodate(tree, eb->start, eb->start + eb->len - 1, | |
3214 | GFP_NOFS); | |
3215 | for (i = 0; i < num_pages; i++) { | |
3216 | page = extent_buffer_page(eb, i); | |
3217 | if ((i == 0 && (eb->start & (PAGE_CACHE_SIZE - 1))) || | |
3218 | ((i == num_pages - 1) && | |
3219 | ((eb->start + eb->len) & (PAGE_CACHE_SIZE - 1)))) { | |
3220 | check_page_uptodate(tree, page); | |
3221 | continue; | |
3222 | } | |
3223 | SetPageUptodate(page); | |
3224 | } | |
3225 | return 0; | |
3226 | } | |
3227 | EXPORT_SYMBOL(set_extent_buffer_uptodate); | |
3228 | ||
ce9adaa5 CM |
3229 | int extent_range_uptodate(struct extent_io_tree *tree, |
3230 | u64 start, u64 end) | |
3231 | { | |
3232 | struct page *page; | |
3233 | int ret; | |
3234 | int pg_uptodate = 1; | |
3235 | int uptodate; | |
3236 | unsigned long index; | |
3237 | ||
3238 | ret = test_range_bit(tree, start, end, EXTENT_UPTODATE, 1); | |
3239 | if (ret) | |
3240 | return 1; | |
3241 | while(start <= end) { | |
3242 | index = start >> PAGE_CACHE_SHIFT; | |
3243 | page = find_get_page(tree->mapping, index); | |
3244 | uptodate = PageUptodate(page); | |
3245 | page_cache_release(page); | |
3246 | if (!uptodate) { | |
3247 | pg_uptodate = 0; | |
3248 | break; | |
3249 | } | |
3250 | start += PAGE_CACHE_SIZE; | |
3251 | } | |
3252 | return pg_uptodate; | |
3253 | } | |
3254 | ||
d1310b2e | 3255 | int extent_buffer_uptodate(struct extent_io_tree *tree, |
ce9adaa5 | 3256 | struct extent_buffer *eb) |
d1310b2e | 3257 | { |
728131d8 | 3258 | int ret = 0; |
ce9adaa5 CM |
3259 | unsigned long num_pages; |
3260 | unsigned long i; | |
728131d8 CM |
3261 | struct page *page; |
3262 | int pg_uptodate = 1; | |
3263 | ||
d1310b2e | 3264 | if (eb->flags & EXTENT_UPTODATE) |
4235298e | 3265 | return 1; |
728131d8 | 3266 | |
4235298e | 3267 | ret = test_range_bit(tree, eb->start, eb->start + eb->len - 1, |
d1310b2e | 3268 | EXTENT_UPTODATE, 1); |
4235298e CM |
3269 | if (ret) |
3270 | return ret; | |
728131d8 CM |
3271 | |
3272 | num_pages = num_extent_pages(eb->start, eb->len); | |
3273 | for (i = 0; i < num_pages; i++) { | |
3274 | page = extent_buffer_page(eb, i); | |
3275 | if (!PageUptodate(page)) { | |
3276 | pg_uptodate = 0; | |
3277 | break; | |
3278 | } | |
3279 | } | |
4235298e | 3280 | return pg_uptodate; |
d1310b2e CM |
3281 | } |
3282 | EXPORT_SYMBOL(extent_buffer_uptodate); | |
3283 | ||
3284 | int read_extent_buffer_pages(struct extent_io_tree *tree, | |
3285 | struct extent_buffer *eb, | |
a86c12c7 | 3286 | u64 start, int wait, |
f188591e | 3287 | get_extent_t *get_extent, int mirror_num) |
d1310b2e CM |
3288 | { |
3289 | unsigned long i; | |
3290 | unsigned long start_i; | |
3291 | struct page *page; | |
3292 | int err; | |
3293 | int ret = 0; | |
ce9adaa5 CM |
3294 | int locked_pages = 0; |
3295 | int all_uptodate = 1; | |
3296 | int inc_all_pages = 0; | |
d1310b2e | 3297 | unsigned long num_pages; |
a86c12c7 | 3298 | struct bio *bio = NULL; |
c8b97818 | 3299 | unsigned long bio_flags = 0; |
a86c12c7 | 3300 | |
d1310b2e CM |
3301 | if (eb->flags & EXTENT_UPTODATE) |
3302 | return 0; | |
3303 | ||
ce9adaa5 | 3304 | if (test_range_bit(tree, eb->start, eb->start + eb->len - 1, |
d1310b2e CM |
3305 | EXTENT_UPTODATE, 1)) { |
3306 | return 0; | |
3307 | } | |
3308 | ||
3309 | if (start) { | |
3310 | WARN_ON(start < eb->start); | |
3311 | start_i = (start >> PAGE_CACHE_SHIFT) - | |
3312 | (eb->start >> PAGE_CACHE_SHIFT); | |
3313 | } else { | |
3314 | start_i = 0; | |
3315 | } | |
3316 | ||
3317 | num_pages = num_extent_pages(eb->start, eb->len); | |
3318 | for (i = start_i; i < num_pages; i++) { | |
3319 | page = extent_buffer_page(eb, i); | |
d1310b2e | 3320 | if (!wait) { |
2db04966 | 3321 | if (!trylock_page(page)) |
ce9adaa5 | 3322 | goto unlock_exit; |
d1310b2e CM |
3323 | } else { |
3324 | lock_page(page); | |
3325 | } | |
ce9adaa5 | 3326 | locked_pages++; |
d1310b2e | 3327 | if (!PageUptodate(page)) { |
ce9adaa5 CM |
3328 | all_uptodate = 0; |
3329 | } | |
3330 | } | |
3331 | if (all_uptodate) { | |
3332 | if (start_i == 0) | |
3333 | eb->flags |= EXTENT_UPTODATE; | |
a1b32a59 CM |
3334 | if (ret) { |
3335 | printk("all up to date but ret is %d\n", ret); | |
3336 | } | |
ce9adaa5 CM |
3337 | goto unlock_exit; |
3338 | } | |
3339 | ||
3340 | for (i = start_i; i < num_pages; i++) { | |
3341 | page = extent_buffer_page(eb, i); | |
3342 | if (inc_all_pages) | |
3343 | page_cache_get(page); | |
3344 | if (!PageUptodate(page)) { | |
3345 | if (start_i == 0) | |
3346 | inc_all_pages = 1; | |
f188591e | 3347 | ClearPageError(page); |
a86c12c7 | 3348 | err = __extent_read_full_page(tree, page, |
f188591e | 3349 | get_extent, &bio, |
c8b97818 | 3350 | mirror_num, &bio_flags); |
d1310b2e CM |
3351 | if (err) { |
3352 | ret = err; | |
a1b32a59 | 3353 | printk("err %d from __extent_read_full_page\n", ret); |
d1310b2e CM |
3354 | } |
3355 | } else { | |
3356 | unlock_page(page); | |
3357 | } | |
3358 | } | |
3359 | ||
a86c12c7 | 3360 | if (bio) |
c8b97818 | 3361 | submit_one_bio(READ, bio, mirror_num, bio_flags); |
a86c12c7 | 3362 | |
d1310b2e | 3363 | if (ret || !wait) { |
a1b32a59 CM |
3364 | if (ret) |
3365 | printk("ret %d wait %d returning\n", ret, wait); | |
d1310b2e CM |
3366 | return ret; |
3367 | } | |
d1310b2e CM |
3368 | for (i = start_i; i < num_pages; i++) { |
3369 | page = extent_buffer_page(eb, i); | |
3370 | wait_on_page_locked(page); | |
3371 | if (!PageUptodate(page)) { | |
a1b32a59 | 3372 | printk("page not uptodate after wait_on_page_locked\n"); |
d1310b2e CM |
3373 | ret = -EIO; |
3374 | } | |
3375 | } | |
3376 | if (!ret) | |
3377 | eb->flags |= EXTENT_UPTODATE; | |
3378 | return ret; | |
ce9adaa5 CM |
3379 | |
3380 | unlock_exit: | |
3381 | i = start_i; | |
3382 | while(locked_pages > 0) { | |
3383 | page = extent_buffer_page(eb, i); | |
3384 | i++; | |
3385 | unlock_page(page); | |
3386 | locked_pages--; | |
3387 | } | |
3388 | return ret; | |
d1310b2e CM |
3389 | } |
3390 | EXPORT_SYMBOL(read_extent_buffer_pages); | |
3391 | ||
3392 | void read_extent_buffer(struct extent_buffer *eb, void *dstv, | |
3393 | unsigned long start, | |
3394 | unsigned long len) | |
3395 | { | |
3396 | size_t cur; | |
3397 | size_t offset; | |
3398 | struct page *page; | |
3399 | char *kaddr; | |
3400 | char *dst = (char *)dstv; | |
3401 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3402 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
d1310b2e CM |
3403 | |
3404 | WARN_ON(start > eb->len); | |
3405 | WARN_ON(start + len > eb->start + eb->len); | |
3406 | ||
3407 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3408 | ||
3409 | while(len > 0) { | |
3410 | page = extent_buffer_page(eb, i); | |
d1310b2e CM |
3411 | |
3412 | cur = min(len, (PAGE_CACHE_SIZE - offset)); | |
3413 | kaddr = kmap_atomic(page, KM_USER1); | |
3414 | memcpy(dst, kaddr + offset, cur); | |
3415 | kunmap_atomic(kaddr, KM_USER1); | |
3416 | ||
3417 | dst += cur; | |
3418 | len -= cur; | |
3419 | offset = 0; | |
3420 | i++; | |
3421 | } | |
3422 | } | |
3423 | EXPORT_SYMBOL(read_extent_buffer); | |
3424 | ||
3425 | int map_private_extent_buffer(struct extent_buffer *eb, unsigned long start, | |
3426 | unsigned long min_len, char **token, char **map, | |
3427 | unsigned long *map_start, | |
3428 | unsigned long *map_len, int km) | |
3429 | { | |
3430 | size_t offset = start & (PAGE_CACHE_SIZE - 1); | |
3431 | char *kaddr; | |
3432 | struct page *p; | |
3433 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3434 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
3435 | unsigned long end_i = (start_offset + start + min_len - 1) >> | |
3436 | PAGE_CACHE_SHIFT; | |
3437 | ||
3438 | if (i != end_i) | |
3439 | return -EINVAL; | |
3440 | ||
3441 | if (i == 0) { | |
3442 | offset = start_offset; | |
3443 | *map_start = 0; | |
3444 | } else { | |
3445 | offset = 0; | |
3446 | *map_start = ((u64)i << PAGE_CACHE_SHIFT) - start_offset; | |
3447 | } | |
3448 | if (start + min_len > eb->len) { | |
3449 | printk("bad mapping eb start %Lu len %lu, wanted %lu %lu\n", eb->start, eb->len, start, min_len); | |
3450 | WARN_ON(1); | |
3451 | } | |
3452 | ||
3453 | p = extent_buffer_page(eb, i); | |
d1310b2e CM |
3454 | kaddr = kmap_atomic(p, km); |
3455 | *token = kaddr; | |
3456 | *map = kaddr + offset; | |
3457 | *map_len = PAGE_CACHE_SIZE - offset; | |
3458 | return 0; | |
3459 | } | |
3460 | EXPORT_SYMBOL(map_private_extent_buffer); | |
3461 | ||
3462 | int map_extent_buffer(struct extent_buffer *eb, unsigned long start, | |
3463 | unsigned long min_len, | |
3464 | char **token, char **map, | |
3465 | unsigned long *map_start, | |
3466 | unsigned long *map_len, int km) | |
3467 | { | |
3468 | int err; | |
3469 | int save = 0; | |
3470 | if (eb->map_token) { | |
3471 | unmap_extent_buffer(eb, eb->map_token, km); | |
3472 | eb->map_token = NULL; | |
3473 | save = 1; | |
934d375b | 3474 | WARN_ON(!mutex_is_locked(&eb->mutex)); |
d1310b2e CM |
3475 | } |
3476 | err = map_private_extent_buffer(eb, start, min_len, token, map, | |
3477 | map_start, map_len, km); | |
3478 | if (!err && save) { | |
3479 | eb->map_token = *token; | |
3480 | eb->kaddr = *map; | |
3481 | eb->map_start = *map_start; | |
3482 | eb->map_len = *map_len; | |
3483 | } | |
3484 | return err; | |
3485 | } | |
3486 | EXPORT_SYMBOL(map_extent_buffer); | |
3487 | ||
3488 | void unmap_extent_buffer(struct extent_buffer *eb, char *token, int km) | |
3489 | { | |
3490 | kunmap_atomic(token, km); | |
3491 | } | |
3492 | EXPORT_SYMBOL(unmap_extent_buffer); | |
3493 | ||
3494 | int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv, | |
3495 | unsigned long start, | |
3496 | unsigned long len) | |
3497 | { | |
3498 | size_t cur; | |
3499 | size_t offset; | |
3500 | struct page *page; | |
3501 | char *kaddr; | |
3502 | char *ptr = (char *)ptrv; | |
3503 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3504 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
3505 | int ret = 0; | |
3506 | ||
3507 | WARN_ON(start > eb->len); | |
3508 | WARN_ON(start + len > eb->start + eb->len); | |
3509 | ||
3510 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3511 | ||
3512 | while(len > 0) { | |
3513 | page = extent_buffer_page(eb, i); | |
d1310b2e CM |
3514 | |
3515 | cur = min(len, (PAGE_CACHE_SIZE - offset)); | |
3516 | ||
3517 | kaddr = kmap_atomic(page, KM_USER0); | |
3518 | ret = memcmp(ptr, kaddr + offset, cur); | |
3519 | kunmap_atomic(kaddr, KM_USER0); | |
3520 | if (ret) | |
3521 | break; | |
3522 | ||
3523 | ptr += cur; | |
3524 | len -= cur; | |
3525 | offset = 0; | |
3526 | i++; | |
3527 | } | |
3528 | return ret; | |
3529 | } | |
3530 | EXPORT_SYMBOL(memcmp_extent_buffer); | |
3531 | ||
3532 | void write_extent_buffer(struct extent_buffer *eb, const void *srcv, | |
3533 | unsigned long start, unsigned long len) | |
3534 | { | |
3535 | size_t cur; | |
3536 | size_t offset; | |
3537 | struct page *page; | |
3538 | char *kaddr; | |
3539 | char *src = (char *)srcv; | |
3540 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3541 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
3542 | ||
3543 | WARN_ON(start > eb->len); | |
3544 | WARN_ON(start + len > eb->start + eb->len); | |
3545 | ||
3546 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3547 | ||
3548 | while(len > 0) { | |
3549 | page = extent_buffer_page(eb, i); | |
3550 | WARN_ON(!PageUptodate(page)); | |
3551 | ||
3552 | cur = min(len, PAGE_CACHE_SIZE - offset); | |
3553 | kaddr = kmap_atomic(page, KM_USER1); | |
3554 | memcpy(kaddr + offset, src, cur); | |
3555 | kunmap_atomic(kaddr, KM_USER1); | |
3556 | ||
3557 | src += cur; | |
3558 | len -= cur; | |
3559 | offset = 0; | |
3560 | i++; | |
3561 | } | |
3562 | } | |
3563 | EXPORT_SYMBOL(write_extent_buffer); | |
3564 | ||
3565 | void memset_extent_buffer(struct extent_buffer *eb, char c, | |
3566 | unsigned long start, unsigned long len) | |
3567 | { | |
3568 | size_t cur; | |
3569 | size_t offset; | |
3570 | struct page *page; | |
3571 | char *kaddr; | |
3572 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3573 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
3574 | ||
3575 | WARN_ON(start > eb->len); | |
3576 | WARN_ON(start + len > eb->start + eb->len); | |
3577 | ||
3578 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3579 | ||
3580 | while(len > 0) { | |
3581 | page = extent_buffer_page(eb, i); | |
3582 | WARN_ON(!PageUptodate(page)); | |
3583 | ||
3584 | cur = min(len, PAGE_CACHE_SIZE - offset); | |
3585 | kaddr = kmap_atomic(page, KM_USER0); | |
3586 | memset(kaddr + offset, c, cur); | |
3587 | kunmap_atomic(kaddr, KM_USER0); | |
3588 | ||
3589 | len -= cur; | |
3590 | offset = 0; | |
3591 | i++; | |
3592 | } | |
3593 | } | |
3594 | EXPORT_SYMBOL(memset_extent_buffer); | |
3595 | ||
3596 | void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src, | |
3597 | unsigned long dst_offset, unsigned long src_offset, | |
3598 | unsigned long len) | |
3599 | { | |
3600 | u64 dst_len = dst->len; | |
3601 | size_t cur; | |
3602 | size_t offset; | |
3603 | struct page *page; | |
3604 | char *kaddr; | |
3605 | size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3606 | unsigned long i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT; | |
3607 | ||
3608 | WARN_ON(src->len != dst_len); | |
3609 | ||
3610 | offset = (start_offset + dst_offset) & | |
3611 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3612 | ||
3613 | while(len > 0) { | |
3614 | page = extent_buffer_page(dst, i); | |
3615 | WARN_ON(!PageUptodate(page)); | |
3616 | ||
3617 | cur = min(len, (unsigned long)(PAGE_CACHE_SIZE - offset)); | |
3618 | ||
3619 | kaddr = kmap_atomic(page, KM_USER0); | |
3620 | read_extent_buffer(src, kaddr + offset, src_offset, cur); | |
3621 | kunmap_atomic(kaddr, KM_USER0); | |
3622 | ||
3623 | src_offset += cur; | |
3624 | len -= cur; | |
3625 | offset = 0; | |
3626 | i++; | |
3627 | } | |
3628 | } | |
3629 | EXPORT_SYMBOL(copy_extent_buffer); | |
3630 | ||
3631 | static void move_pages(struct page *dst_page, struct page *src_page, | |
3632 | unsigned long dst_off, unsigned long src_off, | |
3633 | unsigned long len) | |
3634 | { | |
3635 | char *dst_kaddr = kmap_atomic(dst_page, KM_USER0); | |
3636 | if (dst_page == src_page) { | |
3637 | memmove(dst_kaddr + dst_off, dst_kaddr + src_off, len); | |
3638 | } else { | |
3639 | char *src_kaddr = kmap_atomic(src_page, KM_USER1); | |
3640 | char *p = dst_kaddr + dst_off + len; | |
3641 | char *s = src_kaddr + src_off + len; | |
3642 | ||
3643 | while (len--) | |
3644 | *--p = *--s; | |
3645 | ||
3646 | kunmap_atomic(src_kaddr, KM_USER1); | |
3647 | } | |
3648 | kunmap_atomic(dst_kaddr, KM_USER0); | |
3649 | } | |
3650 | ||
3651 | static void copy_pages(struct page *dst_page, struct page *src_page, | |
3652 | unsigned long dst_off, unsigned long src_off, | |
3653 | unsigned long len) | |
3654 | { | |
3655 | char *dst_kaddr = kmap_atomic(dst_page, KM_USER0); | |
3656 | char *src_kaddr; | |
3657 | ||
3658 | if (dst_page != src_page) | |
3659 | src_kaddr = kmap_atomic(src_page, KM_USER1); | |
3660 | else | |
3661 | src_kaddr = dst_kaddr; | |
3662 | ||
3663 | memcpy(dst_kaddr + dst_off, src_kaddr + src_off, len); | |
3664 | kunmap_atomic(dst_kaddr, KM_USER0); | |
3665 | if (dst_page != src_page) | |
3666 | kunmap_atomic(src_kaddr, KM_USER1); | |
3667 | } | |
3668 | ||
3669 | void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, | |
3670 | unsigned long src_offset, unsigned long len) | |
3671 | { | |
3672 | size_t cur; | |
3673 | size_t dst_off_in_page; | |
3674 | size_t src_off_in_page; | |
3675 | size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3676 | unsigned long dst_i; | |
3677 | unsigned long src_i; | |
3678 | ||
3679 | if (src_offset + len > dst->len) { | |
3680 | printk("memmove bogus src_offset %lu move len %lu len %lu\n", | |
3681 | src_offset, len, dst->len); | |
3682 | BUG_ON(1); | |
3683 | } | |
3684 | if (dst_offset + len > dst->len) { | |
3685 | printk("memmove bogus dst_offset %lu move len %lu len %lu\n", | |
3686 | dst_offset, len, dst->len); | |
3687 | BUG_ON(1); | |
3688 | } | |
3689 | ||
3690 | while(len > 0) { | |
3691 | dst_off_in_page = (start_offset + dst_offset) & | |
3692 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3693 | src_off_in_page = (start_offset + src_offset) & | |
3694 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3695 | ||
3696 | dst_i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT; | |
3697 | src_i = (start_offset + src_offset) >> PAGE_CACHE_SHIFT; | |
3698 | ||
3699 | cur = min(len, (unsigned long)(PAGE_CACHE_SIZE - | |
3700 | src_off_in_page)); | |
3701 | cur = min_t(unsigned long, cur, | |
3702 | (unsigned long)(PAGE_CACHE_SIZE - dst_off_in_page)); | |
3703 | ||
3704 | copy_pages(extent_buffer_page(dst, dst_i), | |
3705 | extent_buffer_page(dst, src_i), | |
3706 | dst_off_in_page, src_off_in_page, cur); | |
3707 | ||
3708 | src_offset += cur; | |
3709 | dst_offset += cur; | |
3710 | len -= cur; | |
3711 | } | |
3712 | } | |
3713 | EXPORT_SYMBOL(memcpy_extent_buffer); | |
3714 | ||
3715 | void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, | |
3716 | unsigned long src_offset, unsigned long len) | |
3717 | { | |
3718 | size_t cur; | |
3719 | size_t dst_off_in_page; | |
3720 | size_t src_off_in_page; | |
3721 | unsigned long dst_end = dst_offset + len - 1; | |
3722 | unsigned long src_end = src_offset + len - 1; | |
3723 | size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3724 | unsigned long dst_i; | |
3725 | unsigned long src_i; | |
3726 | ||
3727 | if (src_offset + len > dst->len) { | |
3728 | printk("memmove bogus src_offset %lu move len %lu len %lu\n", | |
3729 | src_offset, len, dst->len); | |
3730 | BUG_ON(1); | |
3731 | } | |
3732 | if (dst_offset + len > dst->len) { | |
3733 | printk("memmove bogus dst_offset %lu move len %lu len %lu\n", | |
3734 | dst_offset, len, dst->len); | |
3735 | BUG_ON(1); | |
3736 | } | |
3737 | if (dst_offset < src_offset) { | |
3738 | memcpy_extent_buffer(dst, dst_offset, src_offset, len); | |
3739 | return; | |
3740 | } | |
3741 | while(len > 0) { | |
3742 | dst_i = (start_offset + dst_end) >> PAGE_CACHE_SHIFT; | |
3743 | src_i = (start_offset + src_end) >> PAGE_CACHE_SHIFT; | |
3744 | ||
3745 | dst_off_in_page = (start_offset + dst_end) & | |
3746 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3747 | src_off_in_page = (start_offset + src_end) & | |
3748 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3749 | ||
3750 | cur = min_t(unsigned long, len, src_off_in_page + 1); | |
3751 | cur = min(cur, dst_off_in_page + 1); | |
3752 | move_pages(extent_buffer_page(dst, dst_i), | |
3753 | extent_buffer_page(dst, src_i), | |
3754 | dst_off_in_page - cur + 1, | |
3755 | src_off_in_page - cur + 1, cur); | |
3756 | ||
3757 | dst_end -= cur; | |
3758 | src_end -= cur; | |
3759 | len -= cur; | |
3760 | } | |
3761 | } | |
3762 | EXPORT_SYMBOL(memmove_extent_buffer); | |
6af118ce CM |
3763 | |
3764 | int try_release_extent_buffer(struct extent_io_tree *tree, struct page *page) | |
3765 | { | |
3766 | u64 start = page_offset(page); | |
3767 | struct extent_buffer *eb; | |
3768 | int ret = 1; | |
3769 | unsigned long i; | |
3770 | unsigned long num_pages; | |
3771 | ||
3772 | spin_lock(&tree->buffer_lock); | |
3773 | eb = buffer_search(tree, start); | |
3774 | if (!eb) | |
3775 | goto out; | |
3776 | ||
3777 | if (atomic_read(&eb->refs) > 1) { | |
3778 | ret = 0; | |
3779 | goto out; | |
3780 | } | |
3781 | /* at this point we can safely release the extent buffer */ | |
3782 | num_pages = num_extent_pages(eb->start, eb->len); | |
b214107e CH |
3783 | for (i = 0; i < num_pages; i++) |
3784 | page_cache_release(extent_buffer_page(eb, i)); | |
6af118ce CM |
3785 | rb_erase(&eb->rb_node, &tree->buffer); |
3786 | __free_extent_buffer(eb); | |
3787 | out: | |
3788 | spin_unlock(&tree->buffer_lock); | |
3789 | return ret; | |
3790 | } | |
3791 | EXPORT_SYMBOL(try_release_extent_buffer); |