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 |
d397712b | 35 | static DEFINE_SPINLOCK(leak_lock); |
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); |
d397712b CM |
84 | printk(KERN_ERR "btrfs state leak: start %llu end %llu " |
85 | "state %lu in tree %p refs %d\n", | |
86 | (unsigned long long)state->start, | |
87 | (unsigned long long)state->end, | |
88 | state->state, state->tree, atomic_read(&state->refs)); | |
2d2ae547 | 89 | list_del(&state->leak_list); |
d1310b2e CM |
90 | kmem_cache_free(extent_state_cache, state); |
91 | ||
92 | } | |
93 | ||
2d2ae547 CM |
94 | while (!list_empty(&buffers)) { |
95 | eb = list_entry(buffers.next, struct extent_buffer, leak_list); | |
d397712b CM |
96 | printk(KERN_ERR "btrfs buffer leak start %llu len %lu " |
97 | "refs %d\n", (unsigned long long)eb->start, | |
98 | eb->len, atomic_read(&eb->refs)); | |
2d2ae547 CM |
99 | list_del(&eb->leak_list); |
100 | kmem_cache_free(extent_buffer_cache, eb); | |
101 | } | |
d1310b2e CM |
102 | if (extent_state_cache) |
103 | kmem_cache_destroy(extent_state_cache); | |
104 | if (extent_buffer_cache) | |
105 | kmem_cache_destroy(extent_buffer_cache); | |
106 | } | |
107 | ||
108 | void extent_io_tree_init(struct extent_io_tree *tree, | |
109 | struct address_space *mapping, gfp_t mask) | |
110 | { | |
111 | tree->state.rb_node = NULL; | |
6af118ce | 112 | tree->buffer.rb_node = NULL; |
d1310b2e CM |
113 | tree->ops = NULL; |
114 | tree->dirty_bytes = 0; | |
70dec807 | 115 | spin_lock_init(&tree->lock); |
6af118ce | 116 | spin_lock_init(&tree->buffer_lock); |
d1310b2e | 117 | tree->mapping = mapping; |
d1310b2e CM |
118 | } |
119 | EXPORT_SYMBOL(extent_io_tree_init); | |
120 | ||
b2950863 | 121 | static struct extent_state *alloc_extent_state(gfp_t mask) |
d1310b2e CM |
122 | { |
123 | struct extent_state *state; | |
4bef0848 | 124 | #ifdef LEAK_DEBUG |
2d2ae547 | 125 | unsigned long flags; |
4bef0848 | 126 | #endif |
d1310b2e CM |
127 | |
128 | state = kmem_cache_alloc(extent_state_cache, mask); | |
2b114d1d | 129 | if (!state) |
d1310b2e CM |
130 | return state; |
131 | state->state = 0; | |
d1310b2e | 132 | state->private = 0; |
70dec807 | 133 | state->tree = NULL; |
4bef0848 | 134 | #ifdef LEAK_DEBUG |
2d2ae547 CM |
135 | spin_lock_irqsave(&leak_lock, flags); |
136 | list_add(&state->leak_list, &states); | |
137 | spin_unlock_irqrestore(&leak_lock, flags); | |
4bef0848 | 138 | #endif |
d1310b2e CM |
139 | atomic_set(&state->refs, 1); |
140 | init_waitqueue_head(&state->wq); | |
141 | return state; | |
142 | } | |
143 | EXPORT_SYMBOL(alloc_extent_state); | |
144 | ||
b2950863 | 145 | static void free_extent_state(struct extent_state *state) |
d1310b2e | 146 | { |
d1310b2e CM |
147 | if (!state) |
148 | return; | |
149 | if (atomic_dec_and_test(&state->refs)) { | |
4bef0848 | 150 | #ifdef LEAK_DEBUG |
2d2ae547 | 151 | unsigned long flags; |
4bef0848 | 152 | #endif |
70dec807 | 153 | WARN_ON(state->tree); |
4bef0848 | 154 | #ifdef LEAK_DEBUG |
2d2ae547 CM |
155 | spin_lock_irqsave(&leak_lock, flags); |
156 | list_del(&state->leak_list); | |
157 | spin_unlock_irqrestore(&leak_lock, flags); | |
4bef0848 | 158 | #endif |
d1310b2e CM |
159 | kmem_cache_free(extent_state_cache, state); |
160 | } | |
161 | } | |
162 | EXPORT_SYMBOL(free_extent_state); | |
163 | ||
164 | static struct rb_node *tree_insert(struct rb_root *root, u64 offset, | |
165 | struct rb_node *node) | |
166 | { | |
d397712b CM |
167 | struct rb_node **p = &root->rb_node; |
168 | struct rb_node *parent = NULL; | |
d1310b2e CM |
169 | struct tree_entry *entry; |
170 | ||
d397712b | 171 | while (*p) { |
d1310b2e CM |
172 | parent = *p; |
173 | entry = rb_entry(parent, struct tree_entry, rb_node); | |
174 | ||
175 | if (offset < entry->start) | |
176 | p = &(*p)->rb_left; | |
177 | else if (offset > entry->end) | |
178 | p = &(*p)->rb_right; | |
179 | else | |
180 | return parent; | |
181 | } | |
182 | ||
183 | entry = rb_entry(node, struct tree_entry, rb_node); | |
d1310b2e CM |
184 | rb_link_node(node, parent, p); |
185 | rb_insert_color(node, root); | |
186 | return NULL; | |
187 | } | |
188 | ||
80ea96b1 | 189 | static struct rb_node *__etree_search(struct extent_io_tree *tree, u64 offset, |
d1310b2e CM |
190 | struct rb_node **prev_ret, |
191 | struct rb_node **next_ret) | |
192 | { | |
80ea96b1 | 193 | struct rb_root *root = &tree->state; |
d397712b | 194 | struct rb_node *n = root->rb_node; |
d1310b2e CM |
195 | struct rb_node *prev = NULL; |
196 | struct rb_node *orig_prev = NULL; | |
197 | struct tree_entry *entry; | |
198 | struct tree_entry *prev_entry = NULL; | |
199 | ||
d397712b | 200 | while (n) { |
d1310b2e CM |
201 | entry = rb_entry(n, struct tree_entry, rb_node); |
202 | prev = n; | |
203 | prev_entry = entry; | |
204 | ||
205 | if (offset < entry->start) | |
206 | n = n->rb_left; | |
207 | else if (offset > entry->end) | |
208 | n = n->rb_right; | |
d397712b | 209 | else |
d1310b2e CM |
210 | return n; |
211 | } | |
212 | ||
213 | if (prev_ret) { | |
214 | orig_prev = prev; | |
d397712b | 215 | while (prev && offset > prev_entry->end) { |
d1310b2e CM |
216 | prev = rb_next(prev); |
217 | prev_entry = rb_entry(prev, struct tree_entry, rb_node); | |
218 | } | |
219 | *prev_ret = prev; | |
220 | prev = orig_prev; | |
221 | } | |
222 | ||
223 | if (next_ret) { | |
224 | prev_entry = rb_entry(prev, struct tree_entry, rb_node); | |
d397712b | 225 | while (prev && offset < prev_entry->start) { |
d1310b2e CM |
226 | prev = rb_prev(prev); |
227 | prev_entry = rb_entry(prev, struct tree_entry, rb_node); | |
228 | } | |
229 | *next_ret = prev; | |
230 | } | |
231 | return NULL; | |
232 | } | |
233 | ||
80ea96b1 CM |
234 | static inline struct rb_node *tree_search(struct extent_io_tree *tree, |
235 | u64 offset) | |
d1310b2e | 236 | { |
70dec807 | 237 | struct rb_node *prev = NULL; |
d1310b2e | 238 | struct rb_node *ret; |
70dec807 | 239 | |
80ea96b1 | 240 | ret = __etree_search(tree, offset, &prev, NULL); |
d397712b | 241 | if (!ret) |
d1310b2e CM |
242 | return prev; |
243 | return ret; | |
244 | } | |
245 | ||
6af118ce CM |
246 | static struct extent_buffer *buffer_tree_insert(struct extent_io_tree *tree, |
247 | u64 offset, struct rb_node *node) | |
248 | { | |
249 | struct rb_root *root = &tree->buffer; | |
d397712b CM |
250 | struct rb_node **p = &root->rb_node; |
251 | struct rb_node *parent = NULL; | |
6af118ce CM |
252 | struct extent_buffer *eb; |
253 | ||
d397712b | 254 | while (*p) { |
6af118ce CM |
255 | parent = *p; |
256 | eb = rb_entry(parent, struct extent_buffer, rb_node); | |
257 | ||
258 | if (offset < eb->start) | |
259 | p = &(*p)->rb_left; | |
260 | else if (offset > eb->start) | |
261 | p = &(*p)->rb_right; | |
262 | else | |
263 | return eb; | |
264 | } | |
265 | ||
266 | rb_link_node(node, parent, p); | |
267 | rb_insert_color(node, root); | |
268 | return NULL; | |
269 | } | |
270 | ||
271 | static struct extent_buffer *buffer_search(struct extent_io_tree *tree, | |
272 | u64 offset) | |
273 | { | |
274 | struct rb_root *root = &tree->buffer; | |
d397712b | 275 | struct rb_node *n = root->rb_node; |
6af118ce CM |
276 | struct extent_buffer *eb; |
277 | ||
d397712b | 278 | while (n) { |
6af118ce CM |
279 | eb = rb_entry(n, struct extent_buffer, rb_node); |
280 | if (offset < eb->start) | |
281 | n = n->rb_left; | |
282 | else if (offset > eb->start) | |
283 | n = n->rb_right; | |
284 | else | |
285 | return eb; | |
286 | } | |
287 | return NULL; | |
288 | } | |
289 | ||
d1310b2e CM |
290 | /* |
291 | * utility function to look for merge candidates inside a given range. | |
292 | * Any extents with matching state are merged together into a single | |
293 | * extent in the tree. Extents with EXTENT_IO in their state field | |
294 | * are not merged because the end_io handlers need to be able to do | |
295 | * operations on them without sleeping (or doing allocations/splits). | |
296 | * | |
297 | * This should be called with the tree lock held. | |
298 | */ | |
299 | static int merge_state(struct extent_io_tree *tree, | |
300 | struct extent_state *state) | |
301 | { | |
302 | struct extent_state *other; | |
303 | struct rb_node *other_node; | |
304 | ||
5b21f2ed | 305 | if (state->state & (EXTENT_IOBITS | EXTENT_BOUNDARY)) |
d1310b2e CM |
306 | return 0; |
307 | ||
308 | other_node = rb_prev(&state->rb_node); | |
309 | if (other_node) { | |
310 | other = rb_entry(other_node, struct extent_state, rb_node); | |
311 | if (other->end == state->start - 1 && | |
312 | other->state == state->state) { | |
313 | state->start = other->start; | |
70dec807 | 314 | other->tree = NULL; |
d1310b2e CM |
315 | rb_erase(&other->rb_node, &tree->state); |
316 | free_extent_state(other); | |
317 | } | |
318 | } | |
319 | other_node = rb_next(&state->rb_node); | |
320 | if (other_node) { | |
321 | other = rb_entry(other_node, struct extent_state, rb_node); | |
322 | if (other->start == state->end + 1 && | |
323 | other->state == state->state) { | |
324 | other->start = state->start; | |
70dec807 | 325 | state->tree = NULL; |
d1310b2e CM |
326 | rb_erase(&state->rb_node, &tree->state); |
327 | free_extent_state(state); | |
328 | } | |
329 | } | |
330 | return 0; | |
331 | } | |
332 | ||
291d673e CM |
333 | static void set_state_cb(struct extent_io_tree *tree, |
334 | struct extent_state *state, | |
335 | unsigned long bits) | |
336 | { | |
337 | if (tree->ops && tree->ops->set_bit_hook) { | |
338 | tree->ops->set_bit_hook(tree->mapping->host, state->start, | |
b0c68f8b | 339 | state->end, state->state, bits); |
291d673e CM |
340 | } |
341 | } | |
342 | ||
343 | static void clear_state_cb(struct extent_io_tree *tree, | |
344 | struct extent_state *state, | |
345 | unsigned long bits) | |
346 | { | |
c584482b | 347 | if (tree->ops && tree->ops->clear_bit_hook) { |
291d673e | 348 | tree->ops->clear_bit_hook(tree->mapping->host, state->start, |
b0c68f8b | 349 | state->end, state->state, bits); |
291d673e CM |
350 | } |
351 | } | |
352 | ||
d1310b2e CM |
353 | /* |
354 | * insert an extent_state struct into the tree. 'bits' are set on the | |
355 | * struct before it is inserted. | |
356 | * | |
357 | * This may return -EEXIST if the extent is already there, in which case the | |
358 | * state struct is freed. | |
359 | * | |
360 | * The tree lock is not taken internally. This is a utility function and | |
361 | * probably isn't what you want to call (see set/clear_extent_bit). | |
362 | */ | |
363 | static int insert_state(struct extent_io_tree *tree, | |
364 | struct extent_state *state, u64 start, u64 end, | |
365 | int bits) | |
366 | { | |
367 | struct rb_node *node; | |
368 | ||
369 | if (end < start) { | |
d397712b CM |
370 | printk(KERN_ERR "btrfs end < start %llu %llu\n", |
371 | (unsigned long long)end, | |
372 | (unsigned long long)start); | |
d1310b2e CM |
373 | WARN_ON(1); |
374 | } | |
375 | if (bits & EXTENT_DIRTY) | |
376 | tree->dirty_bytes += end - start + 1; | |
b0c68f8b | 377 | set_state_cb(tree, state, bits); |
d1310b2e CM |
378 | state->state |= bits; |
379 | state->start = start; | |
380 | state->end = end; | |
381 | node = tree_insert(&tree->state, end, &state->rb_node); | |
382 | if (node) { | |
383 | struct extent_state *found; | |
384 | found = rb_entry(node, struct extent_state, rb_node); | |
d397712b CM |
385 | printk(KERN_ERR "btrfs found node %llu %llu on insert of " |
386 | "%llu %llu\n", (unsigned long long)found->start, | |
387 | (unsigned long long)found->end, | |
388 | (unsigned long long)start, (unsigned long long)end); | |
d1310b2e CM |
389 | free_extent_state(state); |
390 | return -EEXIST; | |
391 | } | |
70dec807 | 392 | state->tree = tree; |
d1310b2e CM |
393 | merge_state(tree, state); |
394 | return 0; | |
395 | } | |
396 | ||
397 | /* | |
398 | * split a given extent state struct in two, inserting the preallocated | |
399 | * struct 'prealloc' as the newly created second half. 'split' indicates an | |
400 | * offset inside 'orig' where it should be split. | |
401 | * | |
402 | * Before calling, | |
403 | * the tree has 'orig' at [orig->start, orig->end]. After calling, there | |
404 | * are two extent state structs in the tree: | |
405 | * prealloc: [orig->start, split - 1] | |
406 | * orig: [ split, orig->end ] | |
407 | * | |
408 | * The tree locks are not taken by this function. They need to be held | |
409 | * by the caller. | |
410 | */ | |
411 | static int split_state(struct extent_io_tree *tree, struct extent_state *orig, | |
412 | struct extent_state *prealloc, u64 split) | |
413 | { | |
414 | struct rb_node *node; | |
415 | prealloc->start = orig->start; | |
416 | prealloc->end = split - 1; | |
417 | prealloc->state = orig->state; | |
418 | orig->start = split; | |
419 | ||
420 | node = tree_insert(&tree->state, prealloc->end, &prealloc->rb_node); | |
421 | if (node) { | |
422 | struct extent_state *found; | |
423 | found = rb_entry(node, struct extent_state, rb_node); | |
d1310b2e CM |
424 | free_extent_state(prealloc); |
425 | return -EEXIST; | |
426 | } | |
70dec807 | 427 | prealloc->tree = tree; |
d1310b2e CM |
428 | return 0; |
429 | } | |
430 | ||
431 | /* | |
432 | * utility function to clear some bits in an extent state struct. | |
433 | * it will optionally wake up any one waiting on this state (wake == 1), or | |
434 | * forcibly remove the state from the tree (delete == 1). | |
435 | * | |
436 | * If no bits are set on the state struct after clearing things, the | |
437 | * struct is freed and removed from the tree | |
438 | */ | |
439 | static int clear_state_bit(struct extent_io_tree *tree, | |
440 | struct extent_state *state, int bits, int wake, | |
441 | int delete) | |
442 | { | |
443 | int ret = state->state & bits; | |
444 | ||
445 | if ((bits & EXTENT_DIRTY) && (state->state & EXTENT_DIRTY)) { | |
446 | u64 range = state->end - state->start + 1; | |
447 | WARN_ON(range > tree->dirty_bytes); | |
448 | tree->dirty_bytes -= range; | |
449 | } | |
291d673e | 450 | clear_state_cb(tree, state, bits); |
b0c68f8b | 451 | state->state &= ~bits; |
d1310b2e CM |
452 | if (wake) |
453 | wake_up(&state->wq); | |
454 | if (delete || state->state == 0) { | |
70dec807 | 455 | if (state->tree) { |
ae9d1285 | 456 | clear_state_cb(tree, state, state->state); |
d1310b2e | 457 | rb_erase(&state->rb_node, &tree->state); |
70dec807 | 458 | state->tree = NULL; |
d1310b2e CM |
459 | free_extent_state(state); |
460 | } else { | |
461 | WARN_ON(1); | |
462 | } | |
463 | } else { | |
464 | merge_state(tree, state); | |
465 | } | |
466 | return ret; | |
467 | } | |
468 | ||
469 | /* | |
470 | * clear some bits on a range in the tree. This may require splitting | |
471 | * or inserting elements in the tree, so the gfp mask is used to | |
472 | * indicate which allocations or sleeping are allowed. | |
473 | * | |
474 | * pass 'wake' == 1 to kick any sleepers, and 'delete' == 1 to remove | |
475 | * the given range from the tree regardless of state (ie for truncate). | |
476 | * | |
477 | * the range [start, end] is inclusive. | |
478 | * | |
479 | * This takes the tree lock, and returns < 0 on error, > 0 if any of the | |
480 | * bits were already set, or zero if none of the bits were already set. | |
481 | */ | |
482 | int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, | |
483 | int bits, int wake, int delete, gfp_t mask) | |
484 | { | |
485 | struct extent_state *state; | |
486 | struct extent_state *prealloc = NULL; | |
487 | struct rb_node *node; | |
d1310b2e CM |
488 | int err; |
489 | int set = 0; | |
490 | ||
491 | again: | |
492 | if (!prealloc && (mask & __GFP_WAIT)) { | |
493 | prealloc = alloc_extent_state(mask); | |
494 | if (!prealloc) | |
495 | return -ENOMEM; | |
496 | } | |
497 | ||
cad321ad | 498 | spin_lock(&tree->lock); |
d1310b2e CM |
499 | /* |
500 | * this search will find the extents that end after | |
501 | * our range starts | |
502 | */ | |
80ea96b1 | 503 | node = tree_search(tree, start); |
d1310b2e CM |
504 | if (!node) |
505 | goto out; | |
506 | state = rb_entry(node, struct extent_state, rb_node); | |
507 | if (state->start > end) | |
508 | goto out; | |
509 | WARN_ON(state->end < start); | |
510 | ||
511 | /* | |
512 | * | ---- desired range ---- | | |
513 | * | state | or | |
514 | * | ------------- state -------------- | | |
515 | * | |
516 | * We need to split the extent we found, and may flip | |
517 | * bits on second half. | |
518 | * | |
519 | * If the extent we found extends past our range, we | |
520 | * just split and search again. It'll get split again | |
521 | * the next time though. | |
522 | * | |
523 | * If the extent we found is inside our range, we clear | |
524 | * the desired bit on it. | |
525 | */ | |
526 | ||
527 | if (state->start < start) { | |
70dec807 CM |
528 | if (!prealloc) |
529 | prealloc = alloc_extent_state(GFP_ATOMIC); | |
d1310b2e CM |
530 | err = split_state(tree, state, prealloc, start); |
531 | BUG_ON(err == -EEXIST); | |
532 | prealloc = NULL; | |
533 | if (err) | |
534 | goto out; | |
535 | if (state->end <= end) { | |
536 | start = state->end + 1; | |
537 | set |= clear_state_bit(tree, state, bits, | |
538 | wake, delete); | |
539 | } else { | |
540 | start = state->start; | |
541 | } | |
542 | goto search_again; | |
543 | } | |
544 | /* | |
545 | * | ---- desired range ---- | | |
546 | * | state | | |
547 | * We need to split the extent, and clear the bit | |
548 | * on the first half | |
549 | */ | |
550 | if (state->start <= end && state->end > end) { | |
70dec807 CM |
551 | if (!prealloc) |
552 | prealloc = alloc_extent_state(GFP_ATOMIC); | |
d1310b2e CM |
553 | err = split_state(tree, state, prealloc, end + 1); |
554 | BUG_ON(err == -EEXIST); | |
555 | ||
556 | if (wake) | |
557 | wake_up(&state->wq); | |
558 | set |= clear_state_bit(tree, prealloc, bits, | |
559 | wake, delete); | |
560 | prealloc = NULL; | |
561 | goto out; | |
562 | } | |
563 | ||
564 | start = state->end + 1; | |
565 | set |= clear_state_bit(tree, state, bits, wake, delete); | |
566 | goto search_again; | |
567 | ||
568 | out: | |
cad321ad | 569 | spin_unlock(&tree->lock); |
d1310b2e CM |
570 | if (prealloc) |
571 | free_extent_state(prealloc); | |
572 | ||
573 | return set; | |
574 | ||
575 | search_again: | |
576 | if (start > end) | |
577 | goto out; | |
cad321ad | 578 | spin_unlock(&tree->lock); |
d1310b2e CM |
579 | if (mask & __GFP_WAIT) |
580 | cond_resched(); | |
581 | goto again; | |
582 | } | |
583 | EXPORT_SYMBOL(clear_extent_bit); | |
584 | ||
585 | static int wait_on_state(struct extent_io_tree *tree, | |
586 | struct extent_state *state) | |
641f5219 CH |
587 | __releases(tree->lock) |
588 | __acquires(tree->lock) | |
d1310b2e CM |
589 | { |
590 | DEFINE_WAIT(wait); | |
591 | prepare_to_wait(&state->wq, &wait, TASK_UNINTERRUPTIBLE); | |
cad321ad | 592 | spin_unlock(&tree->lock); |
d1310b2e | 593 | schedule(); |
cad321ad | 594 | spin_lock(&tree->lock); |
d1310b2e CM |
595 | finish_wait(&state->wq, &wait); |
596 | return 0; | |
597 | } | |
598 | ||
599 | /* | |
600 | * waits for one or more bits to clear on a range in the state tree. | |
601 | * The range [start, end] is inclusive. | |
602 | * The tree lock is taken by this function | |
603 | */ | |
604 | int wait_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, int bits) | |
605 | { | |
606 | struct extent_state *state; | |
607 | struct rb_node *node; | |
608 | ||
cad321ad | 609 | spin_lock(&tree->lock); |
d1310b2e CM |
610 | again: |
611 | while (1) { | |
612 | /* | |
613 | * this search will find all the extents that end after | |
614 | * our range starts | |
615 | */ | |
80ea96b1 | 616 | node = tree_search(tree, start); |
d1310b2e CM |
617 | if (!node) |
618 | break; | |
619 | ||
620 | state = rb_entry(node, struct extent_state, rb_node); | |
621 | ||
622 | if (state->start > end) | |
623 | goto out; | |
624 | ||
625 | if (state->state & bits) { | |
626 | start = state->start; | |
627 | atomic_inc(&state->refs); | |
628 | wait_on_state(tree, state); | |
629 | free_extent_state(state); | |
630 | goto again; | |
631 | } | |
632 | start = state->end + 1; | |
633 | ||
634 | if (start > end) | |
635 | break; | |
636 | ||
637 | if (need_resched()) { | |
cad321ad | 638 | spin_unlock(&tree->lock); |
d1310b2e | 639 | cond_resched(); |
cad321ad | 640 | spin_lock(&tree->lock); |
d1310b2e CM |
641 | } |
642 | } | |
643 | out: | |
cad321ad | 644 | spin_unlock(&tree->lock); |
d1310b2e CM |
645 | return 0; |
646 | } | |
647 | EXPORT_SYMBOL(wait_extent_bit); | |
648 | ||
649 | static void set_state_bits(struct extent_io_tree *tree, | |
650 | struct extent_state *state, | |
651 | int bits) | |
652 | { | |
653 | if ((bits & EXTENT_DIRTY) && !(state->state & EXTENT_DIRTY)) { | |
654 | u64 range = state->end - state->start + 1; | |
655 | tree->dirty_bytes += range; | |
656 | } | |
291d673e | 657 | set_state_cb(tree, state, bits); |
b0c68f8b | 658 | state->state |= bits; |
d1310b2e CM |
659 | } |
660 | ||
661 | /* | |
662 | * set some bits on a range in the tree. This may require allocations | |
663 | * or sleeping, so the gfp mask is used to indicate what is allowed. | |
664 | * | |
665 | * If 'exclusive' == 1, this will fail with -EEXIST if some part of the | |
666 | * range already has the desired bits set. The start of the existing | |
667 | * range is returned in failed_start in this case. | |
668 | * | |
669 | * [start, end] is inclusive | |
670 | * This takes the tree lock. | |
671 | */ | |
d397712b CM |
672 | static int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, |
673 | int bits, int exclusive, u64 *failed_start, | |
674 | gfp_t mask) | |
d1310b2e CM |
675 | { |
676 | struct extent_state *state; | |
677 | struct extent_state *prealloc = NULL; | |
678 | struct rb_node *node; | |
d1310b2e CM |
679 | int err = 0; |
680 | int set; | |
681 | u64 last_start; | |
682 | u64 last_end; | |
683 | again: | |
684 | if (!prealloc && (mask & __GFP_WAIT)) { | |
685 | prealloc = alloc_extent_state(mask); | |
686 | if (!prealloc) | |
687 | return -ENOMEM; | |
688 | } | |
689 | ||
cad321ad | 690 | spin_lock(&tree->lock); |
d1310b2e CM |
691 | /* |
692 | * this search will find all the extents that end after | |
693 | * our range starts. | |
694 | */ | |
80ea96b1 | 695 | node = tree_search(tree, start); |
d1310b2e CM |
696 | if (!node) { |
697 | err = insert_state(tree, prealloc, start, end, bits); | |
698 | prealloc = NULL; | |
699 | BUG_ON(err == -EEXIST); | |
700 | goto out; | |
701 | } | |
702 | ||
703 | state = rb_entry(node, struct extent_state, rb_node); | |
704 | last_start = state->start; | |
705 | last_end = state->end; | |
706 | ||
707 | /* | |
708 | * | ---- desired range ---- | | |
709 | * | state | | |
710 | * | |
711 | * Just lock what we found and keep going | |
712 | */ | |
713 | if (state->start == start && state->end <= end) { | |
714 | set = state->state & bits; | |
715 | if (set && exclusive) { | |
716 | *failed_start = state->start; | |
717 | err = -EEXIST; | |
718 | goto out; | |
719 | } | |
720 | set_state_bits(tree, state, bits); | |
721 | start = state->end + 1; | |
722 | merge_state(tree, state); | |
723 | goto search_again; | |
724 | } | |
725 | ||
726 | /* | |
727 | * | ---- desired range ---- | | |
728 | * | state | | |
729 | * or | |
730 | * | ------------- state -------------- | | |
731 | * | |
732 | * We need to split the extent we found, and may flip bits on | |
733 | * second half. | |
734 | * | |
735 | * If the extent we found extends past our | |
736 | * range, we just split and search again. It'll get split | |
737 | * again the next time though. | |
738 | * | |
739 | * If the extent we found is inside our range, we set the | |
740 | * desired bit on it. | |
741 | */ | |
742 | if (state->start < start) { | |
743 | set = state->state & bits; | |
744 | if (exclusive && set) { | |
745 | *failed_start = start; | |
746 | err = -EEXIST; | |
747 | goto out; | |
748 | } | |
749 | err = split_state(tree, state, prealloc, start); | |
750 | BUG_ON(err == -EEXIST); | |
751 | prealloc = NULL; | |
752 | if (err) | |
753 | goto out; | |
754 | if (state->end <= end) { | |
755 | set_state_bits(tree, state, bits); | |
756 | start = state->end + 1; | |
757 | merge_state(tree, state); | |
758 | } else { | |
759 | start = state->start; | |
760 | } | |
761 | goto search_again; | |
762 | } | |
763 | /* | |
764 | * | ---- desired range ---- | | |
765 | * | state | or | state | | |
766 | * | |
767 | * There's a hole, we need to insert something in it and | |
768 | * ignore the extent we found. | |
769 | */ | |
770 | if (state->start > start) { | |
771 | u64 this_end; | |
772 | if (end < last_start) | |
773 | this_end = end; | |
774 | else | |
d397712b | 775 | this_end = last_start - 1; |
d1310b2e CM |
776 | err = insert_state(tree, prealloc, start, this_end, |
777 | bits); | |
778 | prealloc = NULL; | |
779 | BUG_ON(err == -EEXIST); | |
780 | if (err) | |
781 | goto out; | |
782 | start = this_end + 1; | |
783 | goto search_again; | |
784 | } | |
785 | /* | |
786 | * | ---- desired range ---- | | |
787 | * | state | | |
788 | * We need to split the extent, and set the bit | |
789 | * on the first half | |
790 | */ | |
791 | if (state->start <= end && state->end > end) { | |
792 | set = state->state & bits; | |
793 | if (exclusive && set) { | |
794 | *failed_start = start; | |
795 | err = -EEXIST; | |
796 | goto out; | |
797 | } | |
798 | err = split_state(tree, state, prealloc, end + 1); | |
799 | BUG_ON(err == -EEXIST); | |
800 | ||
801 | set_state_bits(tree, prealloc, bits); | |
802 | merge_state(tree, prealloc); | |
803 | prealloc = NULL; | |
804 | goto out; | |
805 | } | |
806 | ||
807 | goto search_again; | |
808 | ||
809 | out: | |
cad321ad | 810 | spin_unlock(&tree->lock); |
d1310b2e CM |
811 | if (prealloc) |
812 | free_extent_state(prealloc); | |
813 | ||
814 | return err; | |
815 | ||
816 | search_again: | |
817 | if (start > end) | |
818 | goto out; | |
cad321ad | 819 | spin_unlock(&tree->lock); |
d1310b2e CM |
820 | if (mask & __GFP_WAIT) |
821 | cond_resched(); | |
822 | goto again; | |
823 | } | |
824 | EXPORT_SYMBOL(set_extent_bit); | |
825 | ||
826 | /* wrappers around set/clear extent bit */ | |
827 | int set_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end, | |
828 | gfp_t mask) | |
829 | { | |
830 | return set_extent_bit(tree, start, end, EXTENT_DIRTY, 0, NULL, | |
831 | mask); | |
832 | } | |
833 | EXPORT_SYMBOL(set_extent_dirty); | |
834 | ||
e6dcd2dc CM |
835 | int set_extent_ordered(struct extent_io_tree *tree, u64 start, u64 end, |
836 | gfp_t mask) | |
837 | { | |
838 | return set_extent_bit(tree, start, end, EXTENT_ORDERED, 0, NULL, mask); | |
839 | } | |
840 | EXPORT_SYMBOL(set_extent_ordered); | |
841 | ||
d1310b2e CM |
842 | int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, |
843 | int bits, gfp_t mask) | |
844 | { | |
845 | return set_extent_bit(tree, start, end, bits, 0, NULL, | |
846 | mask); | |
847 | } | |
848 | EXPORT_SYMBOL(set_extent_bits); | |
849 | ||
850 | int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, | |
851 | int bits, gfp_t mask) | |
852 | { | |
853 | return clear_extent_bit(tree, start, end, bits, 0, 0, mask); | |
854 | } | |
855 | EXPORT_SYMBOL(clear_extent_bits); | |
856 | ||
857 | int set_extent_delalloc(struct extent_io_tree *tree, u64 start, u64 end, | |
858 | gfp_t mask) | |
859 | { | |
860 | return set_extent_bit(tree, start, end, | |
e6dcd2dc CM |
861 | EXTENT_DELALLOC | EXTENT_DIRTY, |
862 | 0, NULL, mask); | |
d1310b2e CM |
863 | } |
864 | EXPORT_SYMBOL(set_extent_delalloc); | |
865 | ||
866 | int clear_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end, | |
867 | gfp_t mask) | |
868 | { | |
869 | return clear_extent_bit(tree, start, end, | |
870 | EXTENT_DIRTY | EXTENT_DELALLOC, 0, 0, mask); | |
871 | } | |
872 | EXPORT_SYMBOL(clear_extent_dirty); | |
873 | ||
e6dcd2dc CM |
874 | int clear_extent_ordered(struct extent_io_tree *tree, u64 start, u64 end, |
875 | gfp_t mask) | |
876 | { | |
877 | return clear_extent_bit(tree, start, end, EXTENT_ORDERED, 1, 0, mask); | |
878 | } | |
879 | EXPORT_SYMBOL(clear_extent_ordered); | |
880 | ||
d1310b2e CM |
881 | int set_extent_new(struct extent_io_tree *tree, u64 start, u64 end, |
882 | gfp_t mask) | |
883 | { | |
884 | return set_extent_bit(tree, start, end, EXTENT_NEW, 0, NULL, | |
885 | mask); | |
886 | } | |
887 | EXPORT_SYMBOL(set_extent_new); | |
888 | ||
b2950863 | 889 | static int clear_extent_new(struct extent_io_tree *tree, u64 start, u64 end, |
d1310b2e CM |
890 | gfp_t mask) |
891 | { | |
892 | return clear_extent_bit(tree, start, end, EXTENT_NEW, 0, 0, mask); | |
893 | } | |
d1310b2e CM |
894 | |
895 | int set_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end, | |
896 | gfp_t mask) | |
897 | { | |
898 | return set_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, NULL, | |
899 | mask); | |
900 | } | |
901 | EXPORT_SYMBOL(set_extent_uptodate); | |
902 | ||
d397712b CM |
903 | static int clear_extent_uptodate(struct extent_io_tree *tree, u64 start, |
904 | u64 end, gfp_t mask) | |
d1310b2e CM |
905 | { |
906 | return clear_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, 0, mask); | |
907 | } | |
d1310b2e | 908 | |
b2950863 | 909 | static int set_extent_writeback(struct extent_io_tree *tree, u64 start, u64 end, |
d1310b2e CM |
910 | gfp_t mask) |
911 | { | |
912 | return set_extent_bit(tree, start, end, EXTENT_WRITEBACK, | |
913 | 0, NULL, mask); | |
914 | } | |
d1310b2e | 915 | |
d397712b CM |
916 | static int clear_extent_writeback(struct extent_io_tree *tree, u64 start, |
917 | u64 end, gfp_t mask) | |
d1310b2e CM |
918 | { |
919 | return clear_extent_bit(tree, start, end, EXTENT_WRITEBACK, 1, 0, mask); | |
920 | } | |
d1310b2e CM |
921 | |
922 | int wait_on_extent_writeback(struct extent_io_tree *tree, u64 start, u64 end) | |
923 | { | |
924 | return wait_extent_bit(tree, start, end, EXTENT_WRITEBACK); | |
925 | } | |
926 | EXPORT_SYMBOL(wait_on_extent_writeback); | |
927 | ||
d352ac68 CM |
928 | /* |
929 | * either insert or lock state struct between start and end use mask to tell | |
930 | * us if waiting is desired. | |
931 | */ | |
d1310b2e CM |
932 | int lock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask) |
933 | { | |
934 | int err; | |
935 | u64 failed_start; | |
936 | while (1) { | |
937 | err = set_extent_bit(tree, start, end, EXTENT_LOCKED, 1, | |
938 | &failed_start, mask); | |
939 | if (err == -EEXIST && (mask & __GFP_WAIT)) { | |
940 | wait_extent_bit(tree, failed_start, end, EXTENT_LOCKED); | |
941 | start = failed_start; | |
942 | } else { | |
943 | break; | |
944 | } | |
945 | WARN_ON(start > end); | |
946 | } | |
947 | return err; | |
948 | } | |
949 | EXPORT_SYMBOL(lock_extent); | |
950 | ||
25179201 JB |
951 | int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end, |
952 | gfp_t mask) | |
953 | { | |
954 | int err; | |
955 | u64 failed_start; | |
956 | ||
957 | err = set_extent_bit(tree, start, end, EXTENT_LOCKED, 1, | |
958 | &failed_start, mask); | |
6643558d YZ |
959 | if (err == -EEXIST) { |
960 | if (failed_start > start) | |
961 | clear_extent_bit(tree, start, failed_start - 1, | |
962 | EXTENT_LOCKED, 1, 0, mask); | |
25179201 | 963 | return 0; |
6643558d | 964 | } |
25179201 JB |
965 | return 1; |
966 | } | |
967 | EXPORT_SYMBOL(try_lock_extent); | |
968 | ||
d1310b2e CM |
969 | int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end, |
970 | gfp_t mask) | |
971 | { | |
972 | return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, mask); | |
973 | } | |
974 | EXPORT_SYMBOL(unlock_extent); | |
975 | ||
976 | /* | |
977 | * helper function to set pages and extents in the tree dirty | |
978 | */ | |
979 | int set_range_dirty(struct extent_io_tree *tree, u64 start, u64 end) | |
980 | { | |
981 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
982 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
983 | struct page *page; | |
984 | ||
985 | while (index <= end_index) { | |
986 | page = find_get_page(tree->mapping, index); | |
987 | BUG_ON(!page); | |
988 | __set_page_dirty_nobuffers(page); | |
989 | page_cache_release(page); | |
990 | index++; | |
991 | } | |
992 | set_extent_dirty(tree, start, end, GFP_NOFS); | |
993 | return 0; | |
994 | } | |
995 | EXPORT_SYMBOL(set_range_dirty); | |
996 | ||
997 | /* | |
998 | * helper function to set both pages and extents in the tree writeback | |
999 | */ | |
b2950863 | 1000 | static int set_range_writeback(struct extent_io_tree *tree, u64 start, u64 end) |
d1310b2e CM |
1001 | { |
1002 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1003 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
1004 | struct page *page; | |
1005 | ||
1006 | while (index <= end_index) { | |
1007 | page = find_get_page(tree->mapping, index); | |
1008 | BUG_ON(!page); | |
1009 | set_page_writeback(page); | |
1010 | page_cache_release(page); | |
1011 | index++; | |
1012 | } | |
1013 | set_extent_writeback(tree, start, end, GFP_NOFS); | |
1014 | return 0; | |
1015 | } | |
d1310b2e | 1016 | |
d352ac68 CM |
1017 | /* |
1018 | * find the first offset in the io tree with 'bits' set. zero is | |
1019 | * returned if we find something, and *start_ret and *end_ret are | |
1020 | * set to reflect the state struct that was found. | |
1021 | * | |
1022 | * If nothing was found, 1 is returned, < 0 on error | |
1023 | */ | |
d1310b2e CM |
1024 | int find_first_extent_bit(struct extent_io_tree *tree, u64 start, |
1025 | u64 *start_ret, u64 *end_ret, int bits) | |
1026 | { | |
1027 | struct rb_node *node; | |
1028 | struct extent_state *state; | |
1029 | int ret = 1; | |
1030 | ||
cad321ad | 1031 | spin_lock(&tree->lock); |
d1310b2e CM |
1032 | /* |
1033 | * this search will find all the extents that end after | |
1034 | * our range starts. | |
1035 | */ | |
80ea96b1 | 1036 | node = tree_search(tree, start); |
d397712b | 1037 | if (!node) |
d1310b2e | 1038 | goto out; |
d1310b2e | 1039 | |
d397712b | 1040 | while (1) { |
d1310b2e CM |
1041 | state = rb_entry(node, struct extent_state, rb_node); |
1042 | if (state->end >= start && (state->state & bits)) { | |
1043 | *start_ret = state->start; | |
1044 | *end_ret = state->end; | |
1045 | ret = 0; | |
1046 | break; | |
1047 | } | |
1048 | node = rb_next(node); | |
1049 | if (!node) | |
1050 | break; | |
1051 | } | |
1052 | out: | |
cad321ad | 1053 | spin_unlock(&tree->lock); |
d1310b2e CM |
1054 | return ret; |
1055 | } | |
1056 | EXPORT_SYMBOL(find_first_extent_bit); | |
1057 | ||
d352ac68 CM |
1058 | /* find the first state struct with 'bits' set after 'start', and |
1059 | * return it. tree->lock must be held. NULL will returned if | |
1060 | * nothing was found after 'start' | |
1061 | */ | |
d7fc640e CM |
1062 | struct extent_state *find_first_extent_bit_state(struct extent_io_tree *tree, |
1063 | u64 start, int bits) | |
1064 | { | |
1065 | struct rb_node *node; | |
1066 | struct extent_state *state; | |
1067 | ||
1068 | /* | |
1069 | * this search will find all the extents that end after | |
1070 | * our range starts. | |
1071 | */ | |
1072 | node = tree_search(tree, start); | |
d397712b | 1073 | if (!node) |
d7fc640e | 1074 | goto out; |
d7fc640e | 1075 | |
d397712b | 1076 | while (1) { |
d7fc640e | 1077 | state = rb_entry(node, struct extent_state, rb_node); |
d397712b | 1078 | if (state->end >= start && (state->state & bits)) |
d7fc640e | 1079 | return state; |
d397712b | 1080 | |
d7fc640e CM |
1081 | node = rb_next(node); |
1082 | if (!node) | |
1083 | break; | |
1084 | } | |
1085 | out: | |
1086 | return NULL; | |
1087 | } | |
1088 | EXPORT_SYMBOL(find_first_extent_bit_state); | |
1089 | ||
d352ac68 CM |
1090 | /* |
1091 | * find a contiguous range of bytes in the file marked as delalloc, not | |
1092 | * more than 'max_bytes'. start and end are used to return the range, | |
1093 | * | |
1094 | * 1 is returned if we find something, 0 if nothing was in the tree | |
1095 | */ | |
c8b97818 CM |
1096 | static noinline u64 find_delalloc_range(struct extent_io_tree *tree, |
1097 | u64 *start, u64 *end, u64 max_bytes) | |
d1310b2e CM |
1098 | { |
1099 | struct rb_node *node; | |
1100 | struct extent_state *state; | |
1101 | u64 cur_start = *start; | |
1102 | u64 found = 0; | |
1103 | u64 total_bytes = 0; | |
1104 | ||
cad321ad | 1105 | spin_lock(&tree->lock); |
c8b97818 | 1106 | |
d1310b2e CM |
1107 | /* |
1108 | * this search will find all the extents that end after | |
1109 | * our range starts. | |
1110 | */ | |
80ea96b1 | 1111 | node = tree_search(tree, cur_start); |
2b114d1d | 1112 | if (!node) { |
3b951516 CM |
1113 | if (!found) |
1114 | *end = (u64)-1; | |
d1310b2e CM |
1115 | goto out; |
1116 | } | |
1117 | ||
d397712b | 1118 | while (1) { |
d1310b2e | 1119 | state = rb_entry(node, struct extent_state, rb_node); |
5b21f2ed ZY |
1120 | if (found && (state->start != cur_start || |
1121 | (state->state & EXTENT_BOUNDARY))) { | |
d1310b2e CM |
1122 | goto out; |
1123 | } | |
1124 | if (!(state->state & EXTENT_DELALLOC)) { | |
1125 | if (!found) | |
1126 | *end = state->end; | |
1127 | goto out; | |
1128 | } | |
d1310b2e CM |
1129 | if (!found) |
1130 | *start = state->start; | |
1131 | found++; | |
1132 | *end = state->end; | |
1133 | cur_start = state->end + 1; | |
1134 | node = rb_next(node); | |
1135 | if (!node) | |
1136 | break; | |
1137 | total_bytes += state->end - state->start + 1; | |
1138 | if (total_bytes >= max_bytes) | |
1139 | break; | |
1140 | } | |
1141 | out: | |
cad321ad | 1142 | spin_unlock(&tree->lock); |
d1310b2e CM |
1143 | return found; |
1144 | } | |
1145 | ||
c8b97818 CM |
1146 | static noinline int __unlock_for_delalloc(struct inode *inode, |
1147 | struct page *locked_page, | |
1148 | u64 start, u64 end) | |
1149 | { | |
1150 | int ret; | |
1151 | struct page *pages[16]; | |
1152 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1153 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
1154 | unsigned long nr_pages = end_index - index + 1; | |
1155 | int i; | |
1156 | ||
1157 | if (index == locked_page->index && end_index == index) | |
1158 | return 0; | |
1159 | ||
d397712b | 1160 | while (nr_pages > 0) { |
c8b97818 | 1161 | ret = find_get_pages_contig(inode->i_mapping, index, |
5b050f04 CM |
1162 | min_t(unsigned long, nr_pages, |
1163 | ARRAY_SIZE(pages)), pages); | |
c8b97818 CM |
1164 | for (i = 0; i < ret; i++) { |
1165 | if (pages[i] != locked_page) | |
1166 | unlock_page(pages[i]); | |
1167 | page_cache_release(pages[i]); | |
1168 | } | |
1169 | nr_pages -= ret; | |
1170 | index += ret; | |
1171 | cond_resched(); | |
1172 | } | |
1173 | return 0; | |
1174 | } | |
1175 | ||
1176 | static noinline int lock_delalloc_pages(struct inode *inode, | |
1177 | struct page *locked_page, | |
1178 | u64 delalloc_start, | |
1179 | u64 delalloc_end) | |
1180 | { | |
1181 | unsigned long index = delalloc_start >> PAGE_CACHE_SHIFT; | |
1182 | unsigned long start_index = index; | |
1183 | unsigned long end_index = delalloc_end >> PAGE_CACHE_SHIFT; | |
1184 | unsigned long pages_locked = 0; | |
1185 | struct page *pages[16]; | |
1186 | unsigned long nrpages; | |
1187 | int ret; | |
1188 | int i; | |
1189 | ||
1190 | /* the caller is responsible for locking the start index */ | |
1191 | if (index == locked_page->index && index == end_index) | |
1192 | return 0; | |
1193 | ||
1194 | /* skip the page at the start index */ | |
1195 | nrpages = end_index - index + 1; | |
d397712b | 1196 | while (nrpages > 0) { |
c8b97818 | 1197 | ret = find_get_pages_contig(inode->i_mapping, index, |
5b050f04 CM |
1198 | min_t(unsigned long, |
1199 | nrpages, ARRAY_SIZE(pages)), pages); | |
c8b97818 CM |
1200 | if (ret == 0) { |
1201 | ret = -EAGAIN; | |
1202 | goto done; | |
1203 | } | |
1204 | /* now we have an array of pages, lock them all */ | |
1205 | for (i = 0; i < ret; i++) { | |
1206 | /* | |
1207 | * the caller is taking responsibility for | |
1208 | * locked_page | |
1209 | */ | |
771ed689 | 1210 | if (pages[i] != locked_page) { |
c8b97818 | 1211 | lock_page(pages[i]); |
f2b1c41c CM |
1212 | if (!PageDirty(pages[i]) || |
1213 | pages[i]->mapping != inode->i_mapping) { | |
771ed689 CM |
1214 | ret = -EAGAIN; |
1215 | unlock_page(pages[i]); | |
1216 | page_cache_release(pages[i]); | |
1217 | goto done; | |
1218 | } | |
1219 | } | |
c8b97818 | 1220 | page_cache_release(pages[i]); |
771ed689 | 1221 | pages_locked++; |
c8b97818 | 1222 | } |
c8b97818 CM |
1223 | nrpages -= ret; |
1224 | index += ret; | |
1225 | cond_resched(); | |
1226 | } | |
1227 | ret = 0; | |
1228 | done: | |
1229 | if (ret && pages_locked) { | |
1230 | __unlock_for_delalloc(inode, locked_page, | |
1231 | delalloc_start, | |
1232 | ((u64)(start_index + pages_locked - 1)) << | |
1233 | PAGE_CACHE_SHIFT); | |
1234 | } | |
1235 | return ret; | |
1236 | } | |
1237 | ||
1238 | /* | |
1239 | * find a contiguous range of bytes in the file marked as delalloc, not | |
1240 | * more than 'max_bytes'. start and end are used to return the range, | |
1241 | * | |
1242 | * 1 is returned if we find something, 0 if nothing was in the tree | |
1243 | */ | |
1244 | static noinline u64 find_lock_delalloc_range(struct inode *inode, | |
1245 | struct extent_io_tree *tree, | |
1246 | struct page *locked_page, | |
1247 | u64 *start, u64 *end, | |
1248 | u64 max_bytes) | |
1249 | { | |
1250 | u64 delalloc_start; | |
1251 | u64 delalloc_end; | |
1252 | u64 found; | |
1253 | int ret; | |
1254 | int loops = 0; | |
1255 | ||
1256 | again: | |
1257 | /* step one, find a bunch of delalloc bytes starting at start */ | |
1258 | delalloc_start = *start; | |
1259 | delalloc_end = 0; | |
1260 | found = find_delalloc_range(tree, &delalloc_start, &delalloc_end, | |
1261 | max_bytes); | |
70b99e69 | 1262 | if (!found || delalloc_end <= *start) { |
c8b97818 CM |
1263 | *start = delalloc_start; |
1264 | *end = delalloc_end; | |
1265 | return found; | |
1266 | } | |
1267 | ||
70b99e69 CM |
1268 | /* |
1269 | * start comes from the offset of locked_page. We have to lock | |
1270 | * pages in order, so we can't process delalloc bytes before | |
1271 | * locked_page | |
1272 | */ | |
d397712b | 1273 | if (delalloc_start < *start) |
70b99e69 | 1274 | delalloc_start = *start; |
70b99e69 | 1275 | |
c8b97818 CM |
1276 | /* |
1277 | * make sure to limit the number of pages we try to lock down | |
1278 | * if we're looping. | |
1279 | */ | |
d397712b | 1280 | if (delalloc_end + 1 - delalloc_start > max_bytes && loops) |
771ed689 | 1281 | delalloc_end = delalloc_start + PAGE_CACHE_SIZE - 1; |
d397712b | 1282 | |
c8b97818 CM |
1283 | /* step two, lock all the pages after the page that has start */ |
1284 | ret = lock_delalloc_pages(inode, locked_page, | |
1285 | delalloc_start, delalloc_end); | |
1286 | if (ret == -EAGAIN) { | |
1287 | /* some of the pages are gone, lets avoid looping by | |
1288 | * shortening the size of the delalloc range we're searching | |
1289 | */ | |
1290 | if (!loops) { | |
1291 | unsigned long offset = (*start) & (PAGE_CACHE_SIZE - 1); | |
1292 | max_bytes = PAGE_CACHE_SIZE - offset; | |
1293 | loops = 1; | |
1294 | goto again; | |
1295 | } else { | |
1296 | found = 0; | |
1297 | goto out_failed; | |
1298 | } | |
1299 | } | |
1300 | BUG_ON(ret); | |
1301 | ||
1302 | /* step three, lock the state bits for the whole range */ | |
1303 | lock_extent(tree, delalloc_start, delalloc_end, GFP_NOFS); | |
1304 | ||
1305 | /* then test to make sure it is all still delalloc */ | |
1306 | ret = test_range_bit(tree, delalloc_start, delalloc_end, | |
1307 | EXTENT_DELALLOC, 1); | |
1308 | if (!ret) { | |
1309 | unlock_extent(tree, delalloc_start, delalloc_end, GFP_NOFS); | |
1310 | __unlock_for_delalloc(inode, locked_page, | |
1311 | delalloc_start, delalloc_end); | |
1312 | cond_resched(); | |
1313 | goto again; | |
1314 | } | |
1315 | *start = delalloc_start; | |
1316 | *end = delalloc_end; | |
1317 | out_failed: | |
1318 | return found; | |
1319 | } | |
1320 | ||
1321 | int extent_clear_unlock_delalloc(struct inode *inode, | |
1322 | struct extent_io_tree *tree, | |
1323 | u64 start, u64 end, struct page *locked_page, | |
771ed689 CM |
1324 | int unlock_pages, |
1325 | int clear_unlock, | |
1326 | int clear_delalloc, int clear_dirty, | |
1327 | int set_writeback, | |
c8b97818 CM |
1328 | int end_writeback) |
1329 | { | |
1330 | int ret; | |
1331 | struct page *pages[16]; | |
1332 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1333 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
1334 | unsigned long nr_pages = end_index - index + 1; | |
1335 | int i; | |
771ed689 | 1336 | int clear_bits = 0; |
c8b97818 | 1337 | |
771ed689 CM |
1338 | if (clear_unlock) |
1339 | clear_bits |= EXTENT_LOCKED; | |
c8b97818 CM |
1340 | if (clear_dirty) |
1341 | clear_bits |= EXTENT_DIRTY; | |
1342 | ||
771ed689 CM |
1343 | if (clear_delalloc) |
1344 | clear_bits |= EXTENT_DELALLOC; | |
1345 | ||
c8b97818 | 1346 | clear_extent_bit(tree, start, end, clear_bits, 1, 0, GFP_NOFS); |
771ed689 CM |
1347 | if (!(unlock_pages || clear_dirty || set_writeback || end_writeback)) |
1348 | return 0; | |
c8b97818 | 1349 | |
d397712b | 1350 | while (nr_pages > 0) { |
c8b97818 | 1351 | ret = find_get_pages_contig(inode->i_mapping, index, |
5b050f04 CM |
1352 | min_t(unsigned long, |
1353 | nr_pages, ARRAY_SIZE(pages)), pages); | |
c8b97818 CM |
1354 | for (i = 0; i < ret; i++) { |
1355 | if (pages[i] == locked_page) { | |
1356 | page_cache_release(pages[i]); | |
1357 | continue; | |
1358 | } | |
1359 | if (clear_dirty) | |
1360 | clear_page_dirty_for_io(pages[i]); | |
1361 | if (set_writeback) | |
1362 | set_page_writeback(pages[i]); | |
1363 | if (end_writeback) | |
1364 | end_page_writeback(pages[i]); | |
771ed689 CM |
1365 | if (unlock_pages) |
1366 | unlock_page(pages[i]); | |
c8b97818 CM |
1367 | page_cache_release(pages[i]); |
1368 | } | |
1369 | nr_pages -= ret; | |
1370 | index += ret; | |
1371 | cond_resched(); | |
1372 | } | |
1373 | return 0; | |
1374 | } | |
1375 | EXPORT_SYMBOL(extent_clear_unlock_delalloc); | |
1376 | ||
d352ac68 CM |
1377 | /* |
1378 | * count the number of bytes in the tree that have a given bit(s) | |
1379 | * set. This can be fairly slow, except for EXTENT_DIRTY which is | |
1380 | * cached. The total number found is returned. | |
1381 | */ | |
d1310b2e CM |
1382 | u64 count_range_bits(struct extent_io_tree *tree, |
1383 | u64 *start, u64 search_end, u64 max_bytes, | |
1384 | unsigned long bits) | |
1385 | { | |
1386 | struct rb_node *node; | |
1387 | struct extent_state *state; | |
1388 | u64 cur_start = *start; | |
1389 | u64 total_bytes = 0; | |
1390 | int found = 0; | |
1391 | ||
1392 | if (search_end <= cur_start) { | |
d1310b2e CM |
1393 | WARN_ON(1); |
1394 | return 0; | |
1395 | } | |
1396 | ||
cad321ad | 1397 | spin_lock(&tree->lock); |
d1310b2e CM |
1398 | if (cur_start == 0 && bits == EXTENT_DIRTY) { |
1399 | total_bytes = tree->dirty_bytes; | |
1400 | goto out; | |
1401 | } | |
1402 | /* | |
1403 | * this search will find all the extents that end after | |
1404 | * our range starts. | |
1405 | */ | |
80ea96b1 | 1406 | node = tree_search(tree, cur_start); |
d397712b | 1407 | if (!node) |
d1310b2e | 1408 | goto out; |
d1310b2e | 1409 | |
d397712b | 1410 | while (1) { |
d1310b2e CM |
1411 | state = rb_entry(node, struct extent_state, rb_node); |
1412 | if (state->start > search_end) | |
1413 | break; | |
1414 | if (state->end >= cur_start && (state->state & bits)) { | |
1415 | total_bytes += min(search_end, state->end) + 1 - | |
1416 | max(cur_start, state->start); | |
1417 | if (total_bytes >= max_bytes) | |
1418 | break; | |
1419 | if (!found) { | |
1420 | *start = state->start; | |
1421 | found = 1; | |
1422 | } | |
1423 | } | |
1424 | node = rb_next(node); | |
1425 | if (!node) | |
1426 | break; | |
1427 | } | |
1428 | out: | |
cad321ad | 1429 | spin_unlock(&tree->lock); |
d1310b2e CM |
1430 | return total_bytes; |
1431 | } | |
b2950863 CH |
1432 | |
1433 | #if 0 | |
d1310b2e CM |
1434 | /* |
1435 | * helper function to lock both pages and extents in the tree. | |
1436 | * pages must be locked first. | |
1437 | */ | |
b2950863 | 1438 | static int lock_range(struct extent_io_tree *tree, u64 start, u64 end) |
d1310b2e CM |
1439 | { |
1440 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1441 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
1442 | struct page *page; | |
1443 | int err; | |
1444 | ||
1445 | while (index <= end_index) { | |
1446 | page = grab_cache_page(tree->mapping, index); | |
1447 | if (!page) { | |
1448 | err = -ENOMEM; | |
1449 | goto failed; | |
1450 | } | |
1451 | if (IS_ERR(page)) { | |
1452 | err = PTR_ERR(page); | |
1453 | goto failed; | |
1454 | } | |
1455 | index++; | |
1456 | } | |
1457 | lock_extent(tree, start, end, GFP_NOFS); | |
1458 | return 0; | |
1459 | ||
1460 | failed: | |
1461 | /* | |
1462 | * we failed above in getting the page at 'index', so we undo here | |
1463 | * up to but not including the page at 'index' | |
1464 | */ | |
1465 | end_index = index; | |
1466 | index = start >> PAGE_CACHE_SHIFT; | |
1467 | while (index < end_index) { | |
1468 | page = find_get_page(tree->mapping, index); | |
1469 | unlock_page(page); | |
1470 | page_cache_release(page); | |
1471 | index++; | |
1472 | } | |
1473 | return err; | |
1474 | } | |
d1310b2e CM |
1475 | |
1476 | /* | |
1477 | * helper function to unlock both pages and extents in the tree. | |
1478 | */ | |
b2950863 | 1479 | static int unlock_range(struct extent_io_tree *tree, u64 start, u64 end) |
d1310b2e CM |
1480 | { |
1481 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1482 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
1483 | struct page *page; | |
1484 | ||
1485 | while (index <= end_index) { | |
1486 | page = find_get_page(tree->mapping, index); | |
1487 | unlock_page(page); | |
1488 | page_cache_release(page); | |
1489 | index++; | |
1490 | } | |
1491 | unlock_extent(tree, start, end, GFP_NOFS); | |
1492 | return 0; | |
1493 | } | |
b2950863 | 1494 | #endif |
d1310b2e | 1495 | |
d352ac68 CM |
1496 | /* |
1497 | * set the private field for a given byte offset in the tree. If there isn't | |
1498 | * an extent_state there already, this does nothing. | |
1499 | */ | |
d1310b2e CM |
1500 | int set_state_private(struct extent_io_tree *tree, u64 start, u64 private) |
1501 | { | |
1502 | struct rb_node *node; | |
1503 | struct extent_state *state; | |
1504 | int ret = 0; | |
1505 | ||
cad321ad | 1506 | spin_lock(&tree->lock); |
d1310b2e CM |
1507 | /* |
1508 | * this search will find all the extents that end after | |
1509 | * our range starts. | |
1510 | */ | |
80ea96b1 | 1511 | node = tree_search(tree, start); |
2b114d1d | 1512 | if (!node) { |
d1310b2e CM |
1513 | ret = -ENOENT; |
1514 | goto out; | |
1515 | } | |
1516 | state = rb_entry(node, struct extent_state, rb_node); | |
1517 | if (state->start != start) { | |
1518 | ret = -ENOENT; | |
1519 | goto out; | |
1520 | } | |
1521 | state->private = private; | |
1522 | out: | |
cad321ad | 1523 | spin_unlock(&tree->lock); |
d1310b2e CM |
1524 | return ret; |
1525 | } | |
1526 | ||
1527 | int get_state_private(struct extent_io_tree *tree, u64 start, u64 *private) | |
1528 | { | |
1529 | struct rb_node *node; | |
1530 | struct extent_state *state; | |
1531 | int ret = 0; | |
1532 | ||
cad321ad | 1533 | spin_lock(&tree->lock); |
d1310b2e CM |
1534 | /* |
1535 | * this search will find all the extents that end after | |
1536 | * our range starts. | |
1537 | */ | |
80ea96b1 | 1538 | node = tree_search(tree, start); |
2b114d1d | 1539 | if (!node) { |
d1310b2e CM |
1540 | ret = -ENOENT; |
1541 | goto out; | |
1542 | } | |
1543 | state = rb_entry(node, struct extent_state, rb_node); | |
1544 | if (state->start != start) { | |
1545 | ret = -ENOENT; | |
1546 | goto out; | |
1547 | } | |
1548 | *private = state->private; | |
1549 | out: | |
cad321ad | 1550 | spin_unlock(&tree->lock); |
d1310b2e CM |
1551 | return ret; |
1552 | } | |
1553 | ||
1554 | /* | |
1555 | * searches a range in the state tree for a given mask. | |
70dec807 | 1556 | * If 'filled' == 1, this returns 1 only if every extent in the tree |
d1310b2e CM |
1557 | * has the bits set. Otherwise, 1 is returned if any bit in the |
1558 | * range is found set. | |
1559 | */ | |
1560 | int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end, | |
1561 | int bits, int filled) | |
1562 | { | |
1563 | struct extent_state *state = NULL; | |
1564 | struct rb_node *node; | |
1565 | int bitset = 0; | |
d1310b2e | 1566 | |
cad321ad | 1567 | spin_lock(&tree->lock); |
80ea96b1 | 1568 | node = tree_search(tree, start); |
d1310b2e CM |
1569 | while (node && start <= end) { |
1570 | state = rb_entry(node, struct extent_state, rb_node); | |
1571 | ||
1572 | if (filled && state->start > start) { | |
1573 | bitset = 0; | |
1574 | break; | |
1575 | } | |
1576 | ||
1577 | if (state->start > end) | |
1578 | break; | |
1579 | ||
1580 | if (state->state & bits) { | |
1581 | bitset = 1; | |
1582 | if (!filled) | |
1583 | break; | |
1584 | } else if (filled) { | |
1585 | bitset = 0; | |
1586 | break; | |
1587 | } | |
1588 | start = state->end + 1; | |
1589 | if (start > end) | |
1590 | break; | |
1591 | node = rb_next(node); | |
1592 | if (!node) { | |
1593 | if (filled) | |
1594 | bitset = 0; | |
1595 | break; | |
1596 | } | |
1597 | } | |
cad321ad | 1598 | spin_unlock(&tree->lock); |
d1310b2e CM |
1599 | return bitset; |
1600 | } | |
1601 | EXPORT_SYMBOL(test_range_bit); | |
1602 | ||
1603 | /* | |
1604 | * helper function to set a given page up to date if all the | |
1605 | * extents in the tree for that page are up to date | |
1606 | */ | |
1607 | static int check_page_uptodate(struct extent_io_tree *tree, | |
1608 | struct page *page) | |
1609 | { | |
1610 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
1611 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
1612 | if (test_range_bit(tree, start, end, EXTENT_UPTODATE, 1)) | |
1613 | SetPageUptodate(page); | |
1614 | return 0; | |
1615 | } | |
1616 | ||
1617 | /* | |
1618 | * helper function to unlock a page if all the extents in the tree | |
1619 | * for that page are unlocked | |
1620 | */ | |
1621 | static int check_page_locked(struct extent_io_tree *tree, | |
1622 | struct page *page) | |
1623 | { | |
1624 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
1625 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
1626 | if (!test_range_bit(tree, start, end, EXTENT_LOCKED, 0)) | |
1627 | unlock_page(page); | |
1628 | return 0; | |
1629 | } | |
1630 | ||
1631 | /* | |
1632 | * helper function to end page writeback if all the extents | |
1633 | * in the tree for that page are done with writeback | |
1634 | */ | |
1635 | static int check_page_writeback(struct extent_io_tree *tree, | |
1636 | struct page *page) | |
1637 | { | |
1638 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
1639 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
1640 | if (!test_range_bit(tree, start, end, EXTENT_WRITEBACK, 0)) | |
1641 | end_page_writeback(page); | |
1642 | return 0; | |
1643 | } | |
1644 | ||
1645 | /* lots and lots of room for performance fixes in the end_bio funcs */ | |
1646 | ||
1647 | /* | |
1648 | * after a writepage IO is done, we need to: | |
1649 | * clear the uptodate bits on error | |
1650 | * clear the writeback bits in the extent tree for this IO | |
1651 | * end_page_writeback if the page has no more pending IO | |
1652 | * | |
1653 | * Scheduling is not allowed, so the extent state tree is expected | |
1654 | * to have one and only one object corresponding to this IO. | |
1655 | */ | |
d1310b2e | 1656 | static void end_bio_extent_writepage(struct bio *bio, int err) |
d1310b2e | 1657 | { |
1259ab75 | 1658 | int uptodate = err == 0; |
d1310b2e | 1659 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; |
902b22f3 | 1660 | struct extent_io_tree *tree; |
d1310b2e CM |
1661 | u64 start; |
1662 | u64 end; | |
1663 | int whole_page; | |
1259ab75 | 1664 | int ret; |
d1310b2e | 1665 | |
d1310b2e CM |
1666 | do { |
1667 | struct page *page = bvec->bv_page; | |
902b22f3 DW |
1668 | tree = &BTRFS_I(page->mapping->host)->io_tree; |
1669 | ||
d1310b2e CM |
1670 | start = ((u64)page->index << PAGE_CACHE_SHIFT) + |
1671 | bvec->bv_offset; | |
1672 | end = start + bvec->bv_len - 1; | |
1673 | ||
1674 | if (bvec->bv_offset == 0 && bvec->bv_len == PAGE_CACHE_SIZE) | |
1675 | whole_page = 1; | |
1676 | else | |
1677 | whole_page = 0; | |
1678 | ||
1679 | if (--bvec >= bio->bi_io_vec) | |
1680 | prefetchw(&bvec->bv_page->flags); | |
1259ab75 CM |
1681 | if (tree->ops && tree->ops->writepage_end_io_hook) { |
1682 | ret = tree->ops->writepage_end_io_hook(page, start, | |
902b22f3 | 1683 | end, NULL, uptodate); |
1259ab75 CM |
1684 | if (ret) |
1685 | uptodate = 0; | |
1686 | } | |
1687 | ||
1688 | if (!uptodate && tree->ops && | |
1689 | tree->ops->writepage_io_failed_hook) { | |
1690 | ret = tree->ops->writepage_io_failed_hook(bio, page, | |
902b22f3 | 1691 | start, end, NULL); |
1259ab75 | 1692 | if (ret == 0) { |
1259ab75 CM |
1693 | uptodate = (err == 0); |
1694 | continue; | |
1695 | } | |
1696 | } | |
1697 | ||
d1310b2e CM |
1698 | if (!uptodate) { |
1699 | clear_extent_uptodate(tree, start, end, GFP_ATOMIC); | |
1700 | ClearPageUptodate(page); | |
1701 | SetPageError(page); | |
1702 | } | |
70dec807 | 1703 | |
902b22f3 | 1704 | clear_extent_writeback(tree, start, end, GFP_ATOMIC); |
d1310b2e CM |
1705 | |
1706 | if (whole_page) | |
1707 | end_page_writeback(page); | |
1708 | else | |
1709 | check_page_writeback(tree, page); | |
d1310b2e | 1710 | } while (bvec >= bio->bi_io_vec); |
2b1f55b0 | 1711 | |
d1310b2e | 1712 | bio_put(bio); |
d1310b2e CM |
1713 | } |
1714 | ||
1715 | /* | |
1716 | * after a readpage IO is done, we need to: | |
1717 | * clear the uptodate bits on error | |
1718 | * set the uptodate bits if things worked | |
1719 | * set the page up to date if all extents in the tree are uptodate | |
1720 | * clear the lock bit in the extent tree | |
1721 | * unlock the page if there are no other extents locked for it | |
1722 | * | |
1723 | * Scheduling is not allowed, so the extent state tree is expected | |
1724 | * to have one and only one object corresponding to this IO. | |
1725 | */ | |
d1310b2e | 1726 | static void end_bio_extent_readpage(struct bio *bio, int err) |
d1310b2e CM |
1727 | { |
1728 | int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); | |
1729 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; | |
902b22f3 | 1730 | struct extent_io_tree *tree; |
d1310b2e CM |
1731 | u64 start; |
1732 | u64 end; | |
1733 | int whole_page; | |
1734 | int ret; | |
1735 | ||
d20f7043 CM |
1736 | if (err) |
1737 | uptodate = 0; | |
1738 | ||
d1310b2e CM |
1739 | do { |
1740 | struct page *page = bvec->bv_page; | |
902b22f3 DW |
1741 | tree = &BTRFS_I(page->mapping->host)->io_tree; |
1742 | ||
d1310b2e CM |
1743 | start = ((u64)page->index << PAGE_CACHE_SHIFT) + |
1744 | bvec->bv_offset; | |
1745 | end = start + bvec->bv_len - 1; | |
1746 | ||
1747 | if (bvec->bv_offset == 0 && bvec->bv_len == PAGE_CACHE_SIZE) | |
1748 | whole_page = 1; | |
1749 | else | |
1750 | whole_page = 0; | |
1751 | ||
1752 | if (--bvec >= bio->bi_io_vec) | |
1753 | prefetchw(&bvec->bv_page->flags); | |
1754 | ||
1755 | if (uptodate && tree->ops && tree->ops->readpage_end_io_hook) { | |
70dec807 | 1756 | ret = tree->ops->readpage_end_io_hook(page, start, end, |
902b22f3 | 1757 | NULL); |
d1310b2e CM |
1758 | if (ret) |
1759 | uptodate = 0; | |
1760 | } | |
7e38326f CM |
1761 | if (!uptodate && tree->ops && |
1762 | tree->ops->readpage_io_failed_hook) { | |
1763 | ret = tree->ops->readpage_io_failed_hook(bio, page, | |
902b22f3 | 1764 | start, end, NULL); |
7e38326f | 1765 | if (ret == 0) { |
3b951516 CM |
1766 | uptodate = |
1767 | test_bit(BIO_UPTODATE, &bio->bi_flags); | |
d20f7043 CM |
1768 | if (err) |
1769 | uptodate = 0; | |
7e38326f CM |
1770 | continue; |
1771 | } | |
1772 | } | |
d1310b2e | 1773 | |
771ed689 | 1774 | if (uptodate) { |
902b22f3 DW |
1775 | set_extent_uptodate(tree, start, end, |
1776 | GFP_ATOMIC); | |
771ed689 | 1777 | } |
902b22f3 | 1778 | unlock_extent(tree, start, end, GFP_ATOMIC); |
d1310b2e | 1779 | |
70dec807 CM |
1780 | if (whole_page) { |
1781 | if (uptodate) { | |
1782 | SetPageUptodate(page); | |
1783 | } else { | |
1784 | ClearPageUptodate(page); | |
1785 | SetPageError(page); | |
1786 | } | |
d1310b2e | 1787 | unlock_page(page); |
70dec807 CM |
1788 | } else { |
1789 | if (uptodate) { | |
1790 | check_page_uptodate(tree, page); | |
1791 | } else { | |
1792 | ClearPageUptodate(page); | |
1793 | SetPageError(page); | |
1794 | } | |
d1310b2e | 1795 | check_page_locked(tree, page); |
70dec807 | 1796 | } |
d1310b2e CM |
1797 | } while (bvec >= bio->bi_io_vec); |
1798 | ||
1799 | bio_put(bio); | |
d1310b2e CM |
1800 | } |
1801 | ||
1802 | /* | |
1803 | * IO done from prepare_write is pretty simple, we just unlock | |
1804 | * the structs in the extent tree when done, and set the uptodate bits | |
1805 | * as appropriate. | |
1806 | */ | |
d1310b2e | 1807 | static void end_bio_extent_preparewrite(struct bio *bio, int err) |
d1310b2e CM |
1808 | { |
1809 | const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); | |
1810 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; | |
902b22f3 | 1811 | struct extent_io_tree *tree; |
d1310b2e CM |
1812 | u64 start; |
1813 | u64 end; | |
1814 | ||
d1310b2e CM |
1815 | do { |
1816 | struct page *page = bvec->bv_page; | |
902b22f3 DW |
1817 | tree = &BTRFS_I(page->mapping->host)->io_tree; |
1818 | ||
d1310b2e CM |
1819 | start = ((u64)page->index << PAGE_CACHE_SHIFT) + |
1820 | bvec->bv_offset; | |
1821 | end = start + bvec->bv_len - 1; | |
1822 | ||
1823 | if (--bvec >= bio->bi_io_vec) | |
1824 | prefetchw(&bvec->bv_page->flags); | |
1825 | ||
1826 | if (uptodate) { | |
1827 | set_extent_uptodate(tree, start, end, GFP_ATOMIC); | |
1828 | } else { | |
1829 | ClearPageUptodate(page); | |
1830 | SetPageError(page); | |
1831 | } | |
1832 | ||
1833 | unlock_extent(tree, start, end, GFP_ATOMIC); | |
1834 | ||
1835 | } while (bvec >= bio->bi_io_vec); | |
1836 | ||
1837 | bio_put(bio); | |
d1310b2e CM |
1838 | } |
1839 | ||
1840 | static struct bio * | |
1841 | extent_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs, | |
1842 | gfp_t gfp_flags) | |
1843 | { | |
1844 | struct bio *bio; | |
1845 | ||
1846 | bio = bio_alloc(gfp_flags, nr_vecs); | |
1847 | ||
1848 | if (bio == NULL && (current->flags & PF_MEMALLOC)) { | |
1849 | while (!bio && (nr_vecs /= 2)) | |
1850 | bio = bio_alloc(gfp_flags, nr_vecs); | |
1851 | } | |
1852 | ||
1853 | if (bio) { | |
e1c4b745 | 1854 | bio->bi_size = 0; |
d1310b2e CM |
1855 | bio->bi_bdev = bdev; |
1856 | bio->bi_sector = first_sector; | |
1857 | } | |
1858 | return bio; | |
1859 | } | |
1860 | ||
c8b97818 CM |
1861 | static int submit_one_bio(int rw, struct bio *bio, int mirror_num, |
1862 | unsigned long bio_flags) | |
d1310b2e | 1863 | { |
d1310b2e | 1864 | int ret = 0; |
70dec807 CM |
1865 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; |
1866 | struct page *page = bvec->bv_page; | |
1867 | struct extent_io_tree *tree = bio->bi_private; | |
70dec807 CM |
1868 | u64 start; |
1869 | u64 end; | |
1870 | ||
1871 | start = ((u64)page->index << PAGE_CACHE_SHIFT) + bvec->bv_offset; | |
1872 | end = start + bvec->bv_len - 1; | |
1873 | ||
902b22f3 | 1874 | bio->bi_private = NULL; |
d1310b2e CM |
1875 | |
1876 | bio_get(bio); | |
1877 | ||
065631f6 | 1878 | if (tree->ops && tree->ops->submit_bio_hook) |
f188591e | 1879 | tree->ops->submit_bio_hook(page->mapping->host, rw, bio, |
c8b97818 | 1880 | mirror_num, bio_flags); |
0b86a832 CM |
1881 | else |
1882 | submit_bio(rw, bio); | |
d1310b2e CM |
1883 | if (bio_flagged(bio, BIO_EOPNOTSUPP)) |
1884 | ret = -EOPNOTSUPP; | |
1885 | bio_put(bio); | |
1886 | return ret; | |
1887 | } | |
1888 | ||
1889 | static int submit_extent_page(int rw, struct extent_io_tree *tree, | |
1890 | struct page *page, sector_t sector, | |
1891 | size_t size, unsigned long offset, | |
1892 | struct block_device *bdev, | |
1893 | struct bio **bio_ret, | |
1894 | unsigned long max_pages, | |
f188591e | 1895 | bio_end_io_t end_io_func, |
c8b97818 CM |
1896 | int mirror_num, |
1897 | unsigned long prev_bio_flags, | |
1898 | unsigned long bio_flags) | |
d1310b2e CM |
1899 | { |
1900 | int ret = 0; | |
1901 | struct bio *bio; | |
1902 | int nr; | |
c8b97818 CM |
1903 | int contig = 0; |
1904 | int this_compressed = bio_flags & EXTENT_BIO_COMPRESSED; | |
1905 | int old_compressed = prev_bio_flags & EXTENT_BIO_COMPRESSED; | |
5b050f04 | 1906 | size_t page_size = min_t(size_t, size, PAGE_CACHE_SIZE); |
d1310b2e CM |
1907 | |
1908 | if (bio_ret && *bio_ret) { | |
1909 | bio = *bio_ret; | |
c8b97818 CM |
1910 | if (old_compressed) |
1911 | contig = bio->bi_sector == sector; | |
1912 | else | |
1913 | contig = bio->bi_sector + (bio->bi_size >> 9) == | |
1914 | sector; | |
1915 | ||
1916 | if (prev_bio_flags != bio_flags || !contig || | |
239b14b3 | 1917 | (tree->ops && tree->ops->merge_bio_hook && |
c8b97818 CM |
1918 | tree->ops->merge_bio_hook(page, offset, page_size, bio, |
1919 | bio_flags)) || | |
1920 | bio_add_page(bio, page, page_size, offset) < page_size) { | |
1921 | ret = submit_one_bio(rw, bio, mirror_num, | |
1922 | prev_bio_flags); | |
d1310b2e CM |
1923 | bio = NULL; |
1924 | } else { | |
1925 | return 0; | |
1926 | } | |
1927 | } | |
c8b97818 CM |
1928 | if (this_compressed) |
1929 | nr = BIO_MAX_PAGES; | |
1930 | else | |
1931 | nr = bio_get_nr_vecs(bdev); | |
1932 | ||
d1310b2e | 1933 | bio = extent_bio_alloc(bdev, sector, nr, GFP_NOFS | __GFP_HIGH); |
70dec807 | 1934 | |
c8b97818 | 1935 | bio_add_page(bio, page, page_size, offset); |
d1310b2e CM |
1936 | bio->bi_end_io = end_io_func; |
1937 | bio->bi_private = tree; | |
70dec807 | 1938 | |
d397712b | 1939 | if (bio_ret) |
d1310b2e | 1940 | *bio_ret = bio; |
d397712b | 1941 | else |
c8b97818 | 1942 | ret = submit_one_bio(rw, bio, mirror_num, bio_flags); |
d1310b2e CM |
1943 | |
1944 | return ret; | |
1945 | } | |
1946 | ||
1947 | void set_page_extent_mapped(struct page *page) | |
1948 | { | |
1949 | if (!PagePrivate(page)) { | |
1950 | SetPagePrivate(page); | |
d1310b2e | 1951 | page_cache_get(page); |
6af118ce | 1952 | set_page_private(page, EXTENT_PAGE_PRIVATE); |
d1310b2e CM |
1953 | } |
1954 | } | |
771ed689 | 1955 | EXPORT_SYMBOL(set_page_extent_mapped); |
d1310b2e | 1956 | |
b2950863 | 1957 | static void set_page_extent_head(struct page *page, unsigned long len) |
d1310b2e CM |
1958 | { |
1959 | set_page_private(page, EXTENT_PAGE_PRIVATE_FIRST_PAGE | len << 2); | |
1960 | } | |
1961 | ||
1962 | /* | |
1963 | * basic readpage implementation. Locked extent state structs are inserted | |
1964 | * into the tree that are removed when the IO is done (by the end_io | |
1965 | * handlers) | |
1966 | */ | |
1967 | static int __extent_read_full_page(struct extent_io_tree *tree, | |
1968 | struct page *page, | |
1969 | get_extent_t *get_extent, | |
c8b97818 CM |
1970 | struct bio **bio, int mirror_num, |
1971 | unsigned long *bio_flags) | |
d1310b2e CM |
1972 | { |
1973 | struct inode *inode = page->mapping->host; | |
1974 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
1975 | u64 page_end = start + PAGE_CACHE_SIZE - 1; | |
1976 | u64 end; | |
1977 | u64 cur = start; | |
1978 | u64 extent_offset; | |
1979 | u64 last_byte = i_size_read(inode); | |
1980 | u64 block_start; | |
1981 | u64 cur_end; | |
1982 | sector_t sector; | |
1983 | struct extent_map *em; | |
1984 | struct block_device *bdev; | |
1985 | int ret; | |
1986 | int nr = 0; | |
1987 | size_t page_offset = 0; | |
1988 | size_t iosize; | |
c8b97818 | 1989 | size_t disk_io_size; |
d1310b2e | 1990 | size_t blocksize = inode->i_sb->s_blocksize; |
c8b97818 | 1991 | unsigned long this_bio_flag = 0; |
d1310b2e CM |
1992 | |
1993 | set_page_extent_mapped(page); | |
1994 | ||
1995 | end = page_end; | |
1996 | lock_extent(tree, start, end, GFP_NOFS); | |
1997 | ||
c8b97818 CM |
1998 | if (page->index == last_byte >> PAGE_CACHE_SHIFT) { |
1999 | char *userpage; | |
2000 | size_t zero_offset = last_byte & (PAGE_CACHE_SIZE - 1); | |
2001 | ||
2002 | if (zero_offset) { | |
2003 | iosize = PAGE_CACHE_SIZE - zero_offset; | |
2004 | userpage = kmap_atomic(page, KM_USER0); | |
2005 | memset(userpage + zero_offset, 0, iosize); | |
2006 | flush_dcache_page(page); | |
2007 | kunmap_atomic(userpage, KM_USER0); | |
2008 | } | |
2009 | } | |
d1310b2e CM |
2010 | while (cur <= end) { |
2011 | if (cur >= last_byte) { | |
2012 | char *userpage; | |
2013 | iosize = PAGE_CACHE_SIZE - page_offset; | |
2014 | userpage = kmap_atomic(page, KM_USER0); | |
2015 | memset(userpage + page_offset, 0, iosize); | |
2016 | flush_dcache_page(page); | |
2017 | kunmap_atomic(userpage, KM_USER0); | |
2018 | set_extent_uptodate(tree, cur, cur + iosize - 1, | |
2019 | GFP_NOFS); | |
2020 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); | |
2021 | break; | |
2022 | } | |
2023 | em = get_extent(inode, page, page_offset, cur, | |
2024 | end - cur + 1, 0); | |
2025 | if (IS_ERR(em) || !em) { | |
2026 | SetPageError(page); | |
2027 | unlock_extent(tree, cur, end, GFP_NOFS); | |
2028 | break; | |
2029 | } | |
d1310b2e CM |
2030 | extent_offset = cur - em->start; |
2031 | BUG_ON(extent_map_end(em) <= cur); | |
2032 | BUG_ON(end < cur); | |
2033 | ||
c8b97818 CM |
2034 | if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) |
2035 | this_bio_flag = EXTENT_BIO_COMPRESSED; | |
2036 | ||
d1310b2e CM |
2037 | iosize = min(extent_map_end(em) - cur, end - cur + 1); |
2038 | cur_end = min(extent_map_end(em) - 1, end); | |
2039 | iosize = (iosize + blocksize - 1) & ~((u64)blocksize - 1); | |
c8b97818 CM |
2040 | if (this_bio_flag & EXTENT_BIO_COMPRESSED) { |
2041 | disk_io_size = em->block_len; | |
2042 | sector = em->block_start >> 9; | |
2043 | } else { | |
2044 | sector = (em->block_start + extent_offset) >> 9; | |
2045 | disk_io_size = iosize; | |
2046 | } | |
d1310b2e CM |
2047 | bdev = em->bdev; |
2048 | block_start = em->block_start; | |
d899e052 YZ |
2049 | if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) |
2050 | block_start = EXTENT_MAP_HOLE; | |
d1310b2e CM |
2051 | free_extent_map(em); |
2052 | em = NULL; | |
2053 | ||
2054 | /* we've found a hole, just zero and go on */ | |
2055 | if (block_start == EXTENT_MAP_HOLE) { | |
2056 | char *userpage; | |
2057 | userpage = kmap_atomic(page, KM_USER0); | |
2058 | memset(userpage + page_offset, 0, iosize); | |
2059 | flush_dcache_page(page); | |
2060 | kunmap_atomic(userpage, KM_USER0); | |
2061 | ||
2062 | set_extent_uptodate(tree, cur, cur + iosize - 1, | |
2063 | GFP_NOFS); | |
2064 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); | |
2065 | cur = cur + iosize; | |
2066 | page_offset += iosize; | |
2067 | continue; | |
2068 | } | |
2069 | /* the get_extent function already copied into the page */ | |
2070 | if (test_range_bit(tree, cur, cur_end, EXTENT_UPTODATE, 1)) { | |
a1b32a59 | 2071 | check_page_uptodate(tree, page); |
d1310b2e CM |
2072 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); |
2073 | cur = cur + iosize; | |
2074 | page_offset += iosize; | |
2075 | continue; | |
2076 | } | |
70dec807 CM |
2077 | /* we have an inline extent but it didn't get marked up |
2078 | * to date. Error out | |
2079 | */ | |
2080 | if (block_start == EXTENT_MAP_INLINE) { | |
2081 | SetPageError(page); | |
2082 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); | |
2083 | cur = cur + iosize; | |
2084 | page_offset += iosize; | |
2085 | continue; | |
2086 | } | |
d1310b2e CM |
2087 | |
2088 | ret = 0; | |
2089 | if (tree->ops && tree->ops->readpage_io_hook) { | |
2090 | ret = tree->ops->readpage_io_hook(page, cur, | |
2091 | cur + iosize - 1); | |
2092 | } | |
2093 | if (!ret) { | |
89642229 CM |
2094 | unsigned long pnr = (last_byte >> PAGE_CACHE_SHIFT) + 1; |
2095 | pnr -= page->index; | |
d1310b2e | 2096 | ret = submit_extent_page(READ, tree, page, |
c8b97818 | 2097 | sector, disk_io_size, page_offset, |
89642229 | 2098 | bdev, bio, pnr, |
c8b97818 CM |
2099 | end_bio_extent_readpage, mirror_num, |
2100 | *bio_flags, | |
2101 | this_bio_flag); | |
89642229 | 2102 | nr++; |
c8b97818 | 2103 | *bio_flags = this_bio_flag; |
d1310b2e CM |
2104 | } |
2105 | if (ret) | |
2106 | SetPageError(page); | |
2107 | cur = cur + iosize; | |
2108 | page_offset += iosize; | |
d1310b2e CM |
2109 | } |
2110 | if (!nr) { | |
2111 | if (!PageError(page)) | |
2112 | SetPageUptodate(page); | |
2113 | unlock_page(page); | |
2114 | } | |
2115 | return 0; | |
2116 | } | |
2117 | ||
2118 | int extent_read_full_page(struct extent_io_tree *tree, struct page *page, | |
2119 | get_extent_t *get_extent) | |
2120 | { | |
2121 | struct bio *bio = NULL; | |
c8b97818 | 2122 | unsigned long bio_flags = 0; |
d1310b2e CM |
2123 | int ret; |
2124 | ||
c8b97818 CM |
2125 | ret = __extent_read_full_page(tree, page, get_extent, &bio, 0, |
2126 | &bio_flags); | |
d1310b2e | 2127 | if (bio) |
c8b97818 | 2128 | submit_one_bio(READ, bio, 0, bio_flags); |
d1310b2e CM |
2129 | return ret; |
2130 | } | |
2131 | EXPORT_SYMBOL(extent_read_full_page); | |
2132 | ||
2133 | /* | |
2134 | * the writepage semantics are similar to regular writepage. extent | |
2135 | * records are inserted to lock ranges in the tree, and as dirty areas | |
2136 | * are found, they are marked writeback. Then the lock bits are removed | |
2137 | * and the end_io handler clears the writeback ranges | |
2138 | */ | |
2139 | static int __extent_writepage(struct page *page, struct writeback_control *wbc, | |
2140 | void *data) | |
2141 | { | |
2142 | struct inode *inode = page->mapping->host; | |
2143 | struct extent_page_data *epd = data; | |
2144 | struct extent_io_tree *tree = epd->tree; | |
2145 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
2146 | u64 delalloc_start; | |
2147 | u64 page_end = start + PAGE_CACHE_SIZE - 1; | |
2148 | u64 end; | |
2149 | u64 cur = start; | |
2150 | u64 extent_offset; | |
2151 | u64 last_byte = i_size_read(inode); | |
2152 | u64 block_start; | |
2153 | u64 iosize; | |
e6dcd2dc | 2154 | u64 unlock_start; |
d1310b2e CM |
2155 | sector_t sector; |
2156 | struct extent_map *em; | |
2157 | struct block_device *bdev; | |
2158 | int ret; | |
2159 | int nr = 0; | |
7f3c74fb | 2160 | size_t pg_offset = 0; |
d1310b2e CM |
2161 | size_t blocksize; |
2162 | loff_t i_size = i_size_read(inode); | |
2163 | unsigned long end_index = i_size >> PAGE_CACHE_SHIFT; | |
2164 | u64 nr_delalloc; | |
2165 | u64 delalloc_end; | |
c8b97818 CM |
2166 | int page_started; |
2167 | int compressed; | |
771ed689 | 2168 | unsigned long nr_written = 0; |
d1310b2e CM |
2169 | |
2170 | WARN_ON(!PageLocked(page)); | |
7f3c74fb | 2171 | pg_offset = i_size & (PAGE_CACHE_SIZE - 1); |
211c17f5 | 2172 | if (page->index > end_index || |
7f3c74fb | 2173 | (page->index == end_index && !pg_offset)) { |
39be25cd | 2174 | page->mapping->a_ops->invalidatepage(page, 0); |
d1310b2e CM |
2175 | unlock_page(page); |
2176 | return 0; | |
2177 | } | |
2178 | ||
2179 | if (page->index == end_index) { | |
2180 | char *userpage; | |
2181 | ||
d1310b2e | 2182 | userpage = kmap_atomic(page, KM_USER0); |
7f3c74fb CM |
2183 | memset(userpage + pg_offset, 0, |
2184 | PAGE_CACHE_SIZE - pg_offset); | |
d1310b2e | 2185 | kunmap_atomic(userpage, KM_USER0); |
211c17f5 | 2186 | flush_dcache_page(page); |
d1310b2e | 2187 | } |
7f3c74fb | 2188 | pg_offset = 0; |
d1310b2e CM |
2189 | |
2190 | set_page_extent_mapped(page); | |
2191 | ||
2192 | delalloc_start = start; | |
2193 | delalloc_end = 0; | |
c8b97818 | 2194 | page_started = 0; |
771ed689 | 2195 | if (!epd->extent_locked) { |
d397712b | 2196 | while (delalloc_end < page_end) { |
771ed689 | 2197 | nr_delalloc = find_lock_delalloc_range(inode, tree, |
c8b97818 CM |
2198 | page, |
2199 | &delalloc_start, | |
d1310b2e CM |
2200 | &delalloc_end, |
2201 | 128 * 1024 * 1024); | |
771ed689 CM |
2202 | if (nr_delalloc == 0) { |
2203 | delalloc_start = delalloc_end + 1; | |
2204 | continue; | |
2205 | } | |
2206 | tree->ops->fill_delalloc(inode, page, delalloc_start, | |
2207 | delalloc_end, &page_started, | |
2208 | &nr_written); | |
d1310b2e | 2209 | delalloc_start = delalloc_end + 1; |
d1310b2e | 2210 | } |
c8b97818 | 2211 | |
771ed689 CM |
2212 | /* did the fill delalloc function already unlock and start |
2213 | * the IO? | |
2214 | */ | |
2215 | if (page_started) { | |
2216 | ret = 0; | |
2217 | goto update_nr_written; | |
2218 | } | |
c8b97818 | 2219 | } |
d1310b2e | 2220 | lock_extent(tree, start, page_end, GFP_NOFS); |
771ed689 | 2221 | |
e6dcd2dc | 2222 | unlock_start = start; |
d1310b2e | 2223 | |
247e743c | 2224 | if (tree->ops && tree->ops->writepage_start_hook) { |
c8b97818 CM |
2225 | ret = tree->ops->writepage_start_hook(page, start, |
2226 | page_end); | |
247e743c CM |
2227 | if (ret == -EAGAIN) { |
2228 | unlock_extent(tree, start, page_end, GFP_NOFS); | |
2229 | redirty_page_for_writepage(wbc, page); | |
2230 | unlock_page(page); | |
771ed689 CM |
2231 | ret = 0; |
2232 | goto update_nr_written; | |
247e743c CM |
2233 | } |
2234 | } | |
2235 | ||
771ed689 CM |
2236 | nr_written++; |
2237 | ||
d1310b2e | 2238 | end = page_end; |
d397712b CM |
2239 | if (test_range_bit(tree, start, page_end, EXTENT_DELALLOC, 0)) |
2240 | printk(KERN_ERR "btrfs delalloc bits after lock_extent\n"); | |
d1310b2e CM |
2241 | |
2242 | if (last_byte <= start) { | |
2243 | clear_extent_dirty(tree, start, page_end, GFP_NOFS); | |
e6dcd2dc CM |
2244 | unlock_extent(tree, start, page_end, GFP_NOFS); |
2245 | if (tree->ops && tree->ops->writepage_end_io_hook) | |
2246 | tree->ops->writepage_end_io_hook(page, start, | |
2247 | page_end, NULL, 1); | |
2248 | unlock_start = page_end + 1; | |
d1310b2e CM |
2249 | goto done; |
2250 | } | |
2251 | ||
2252 | set_extent_uptodate(tree, start, page_end, GFP_NOFS); | |
2253 | blocksize = inode->i_sb->s_blocksize; | |
2254 | ||
2255 | while (cur <= end) { | |
2256 | if (cur >= last_byte) { | |
2257 | clear_extent_dirty(tree, cur, page_end, GFP_NOFS); | |
e6dcd2dc CM |
2258 | unlock_extent(tree, unlock_start, page_end, GFP_NOFS); |
2259 | if (tree->ops && tree->ops->writepage_end_io_hook) | |
2260 | tree->ops->writepage_end_io_hook(page, cur, | |
2261 | page_end, NULL, 1); | |
2262 | unlock_start = page_end + 1; | |
d1310b2e CM |
2263 | break; |
2264 | } | |
7f3c74fb | 2265 | em = epd->get_extent(inode, page, pg_offset, cur, |
d1310b2e CM |
2266 | end - cur + 1, 1); |
2267 | if (IS_ERR(em) || !em) { | |
2268 | SetPageError(page); | |
2269 | break; | |
2270 | } | |
2271 | ||
2272 | extent_offset = cur - em->start; | |
2273 | BUG_ON(extent_map_end(em) <= cur); | |
2274 | BUG_ON(end < cur); | |
2275 | iosize = min(extent_map_end(em) - cur, end - cur + 1); | |
2276 | iosize = (iosize + blocksize - 1) & ~((u64)blocksize - 1); | |
2277 | sector = (em->block_start + extent_offset) >> 9; | |
2278 | bdev = em->bdev; | |
2279 | block_start = em->block_start; | |
c8b97818 | 2280 | compressed = test_bit(EXTENT_FLAG_COMPRESSED, &em->flags); |
d1310b2e CM |
2281 | free_extent_map(em); |
2282 | em = NULL; | |
2283 | ||
c8b97818 CM |
2284 | /* |
2285 | * compressed and inline extents are written through other | |
2286 | * paths in the FS | |
2287 | */ | |
2288 | if (compressed || block_start == EXTENT_MAP_HOLE || | |
d1310b2e CM |
2289 | block_start == EXTENT_MAP_INLINE) { |
2290 | clear_extent_dirty(tree, cur, | |
2291 | cur + iosize - 1, GFP_NOFS); | |
e6dcd2dc | 2292 | |
d397712b | 2293 | unlock_extent(tree, unlock_start, cur + iosize - 1, |
e6dcd2dc | 2294 | GFP_NOFS); |
7f3c74fb | 2295 | |
c8b97818 CM |
2296 | /* |
2297 | * end_io notification does not happen here for | |
2298 | * compressed extents | |
2299 | */ | |
2300 | if (!compressed && tree->ops && | |
2301 | tree->ops->writepage_end_io_hook) | |
e6dcd2dc CM |
2302 | tree->ops->writepage_end_io_hook(page, cur, |
2303 | cur + iosize - 1, | |
2304 | NULL, 1); | |
c8b97818 CM |
2305 | else if (compressed) { |
2306 | /* we don't want to end_page_writeback on | |
2307 | * a compressed extent. this happens | |
2308 | * elsewhere | |
2309 | */ | |
2310 | nr++; | |
2311 | } | |
2312 | ||
2313 | cur += iosize; | |
7f3c74fb | 2314 | pg_offset += iosize; |
e6dcd2dc | 2315 | unlock_start = cur; |
d1310b2e CM |
2316 | continue; |
2317 | } | |
d1310b2e CM |
2318 | /* leave this out until we have a page_mkwrite call */ |
2319 | if (0 && !test_range_bit(tree, cur, cur + iosize - 1, | |
2320 | EXTENT_DIRTY, 0)) { | |
2321 | cur = cur + iosize; | |
7f3c74fb | 2322 | pg_offset += iosize; |
d1310b2e CM |
2323 | continue; |
2324 | } | |
c8b97818 | 2325 | |
d1310b2e CM |
2326 | clear_extent_dirty(tree, cur, cur + iosize - 1, GFP_NOFS); |
2327 | if (tree->ops && tree->ops->writepage_io_hook) { | |
2328 | ret = tree->ops->writepage_io_hook(page, cur, | |
2329 | cur + iosize - 1); | |
2330 | } else { | |
2331 | ret = 0; | |
2332 | } | |
1259ab75 | 2333 | if (ret) { |
d1310b2e | 2334 | SetPageError(page); |
1259ab75 | 2335 | } else { |
d1310b2e | 2336 | unsigned long max_nr = end_index + 1; |
7f3c74fb | 2337 | |
d1310b2e CM |
2338 | set_range_writeback(tree, cur, cur + iosize - 1); |
2339 | if (!PageWriteback(page)) { | |
d397712b CM |
2340 | printk(KERN_ERR "btrfs warning page %lu not " |
2341 | "writeback, cur %llu end %llu\n", | |
2342 | page->index, (unsigned long long)cur, | |
d1310b2e CM |
2343 | (unsigned long long)end); |
2344 | } | |
2345 | ||
2346 | ret = submit_extent_page(WRITE, tree, page, sector, | |
7f3c74fb | 2347 | iosize, pg_offset, bdev, |
d1310b2e | 2348 | &epd->bio, max_nr, |
c8b97818 CM |
2349 | end_bio_extent_writepage, |
2350 | 0, 0, 0); | |
d1310b2e CM |
2351 | if (ret) |
2352 | SetPageError(page); | |
2353 | } | |
2354 | cur = cur + iosize; | |
7f3c74fb | 2355 | pg_offset += iosize; |
d1310b2e CM |
2356 | nr++; |
2357 | } | |
2358 | done: | |
2359 | if (nr == 0) { | |
2360 | /* make sure the mapping tag for page dirty gets cleared */ | |
2361 | set_page_writeback(page); | |
2362 | end_page_writeback(page); | |
2363 | } | |
e6dcd2dc CM |
2364 | if (unlock_start <= page_end) |
2365 | unlock_extent(tree, unlock_start, page_end, GFP_NOFS); | |
d1310b2e | 2366 | unlock_page(page); |
771ed689 CM |
2367 | |
2368 | update_nr_written: | |
2369 | wbc->nr_to_write -= nr_written; | |
2370 | if (wbc->range_cyclic || (wbc->nr_to_write > 0 && | |
2371 | wbc->range_start == 0 && wbc->range_end == LLONG_MAX)) | |
2372 | page->mapping->writeback_index = page->index + nr_written; | |
d1310b2e CM |
2373 | return 0; |
2374 | } | |
2375 | ||
d1310b2e | 2376 | /** |
4bef0848 | 2377 | * write_cache_pages - walk the list of dirty pages of the given address space and write all of them. |
d1310b2e CM |
2378 | * @mapping: address space structure to write |
2379 | * @wbc: subtract the number of written pages from *@wbc->nr_to_write | |
2380 | * @writepage: function called for each page | |
2381 | * @data: data passed to writepage function | |
2382 | * | |
2383 | * If a page is already under I/O, write_cache_pages() skips it, even | |
2384 | * if it's dirty. This is desirable behaviour for memory-cleaning writeback, | |
2385 | * but it is INCORRECT for data-integrity system calls such as fsync(). fsync() | |
2386 | * and msync() need to guarantee that all the data which was dirty at the time | |
2387 | * the call was made get new I/O started against them. If wbc->sync_mode is | |
2388 | * WB_SYNC_ALL then we were called for data integrity and we must wait for | |
2389 | * existing IO to complete. | |
2390 | */ | |
b2950863 | 2391 | static int extent_write_cache_pages(struct extent_io_tree *tree, |
4bef0848 CM |
2392 | struct address_space *mapping, |
2393 | struct writeback_control *wbc, | |
d2c3f4f6 CM |
2394 | writepage_t writepage, void *data, |
2395 | void (*flush_fn)(void *)) | |
d1310b2e CM |
2396 | { |
2397 | struct backing_dev_info *bdi = mapping->backing_dev_info; | |
2398 | int ret = 0; | |
2399 | int done = 0; | |
2400 | struct pagevec pvec; | |
2401 | int nr_pages; | |
2402 | pgoff_t index; | |
2403 | pgoff_t end; /* Inclusive */ | |
2404 | int scanned = 0; | |
2405 | int range_whole = 0; | |
2406 | ||
2407 | if (wbc->nonblocking && bdi_write_congested(bdi)) { | |
2408 | wbc->encountered_congestion = 1; | |
2409 | return 0; | |
2410 | } | |
2411 | ||
2412 | pagevec_init(&pvec, 0); | |
2413 | if (wbc->range_cyclic) { | |
2414 | index = mapping->writeback_index; /* Start from prev offset */ | |
2415 | end = -1; | |
2416 | } else { | |
2417 | index = wbc->range_start >> PAGE_CACHE_SHIFT; | |
2418 | end = wbc->range_end >> PAGE_CACHE_SHIFT; | |
2419 | if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) | |
2420 | range_whole = 1; | |
2421 | scanned = 1; | |
2422 | } | |
2423 | retry: | |
2424 | while (!done && (index <= end) && | |
2425 | (nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, | |
d397712b CM |
2426 | PAGECACHE_TAG_DIRTY, min(end - index, |
2427 | (pgoff_t)PAGEVEC_SIZE-1) + 1))) { | |
d1310b2e CM |
2428 | unsigned i; |
2429 | ||
2430 | scanned = 1; | |
2431 | for (i = 0; i < nr_pages; i++) { | |
2432 | struct page *page = pvec.pages[i]; | |
2433 | ||
2434 | /* | |
2435 | * At this point we hold neither mapping->tree_lock nor | |
2436 | * lock on the page itself: the page may be truncated or | |
2437 | * invalidated (changing page->mapping to NULL), or even | |
2438 | * swizzled back from swapper_space to tmpfs file | |
2439 | * mapping | |
2440 | */ | |
4bef0848 CM |
2441 | if (tree->ops && tree->ops->write_cache_pages_lock_hook) |
2442 | tree->ops->write_cache_pages_lock_hook(page); | |
2443 | else | |
2444 | lock_page(page); | |
d1310b2e CM |
2445 | |
2446 | if (unlikely(page->mapping != mapping)) { | |
2447 | unlock_page(page); | |
2448 | continue; | |
2449 | } | |
2450 | ||
2451 | if (!wbc->range_cyclic && page->index > end) { | |
2452 | done = 1; | |
2453 | unlock_page(page); | |
2454 | continue; | |
2455 | } | |
2456 | ||
d2c3f4f6 | 2457 | if (wbc->sync_mode != WB_SYNC_NONE) { |
0e6bd956 CM |
2458 | if (PageWriteback(page)) |
2459 | flush_fn(data); | |
d1310b2e | 2460 | wait_on_page_writeback(page); |
d2c3f4f6 | 2461 | } |
d1310b2e CM |
2462 | |
2463 | if (PageWriteback(page) || | |
2464 | !clear_page_dirty_for_io(page)) { | |
2465 | unlock_page(page); | |
2466 | continue; | |
2467 | } | |
2468 | ||
2469 | ret = (*writepage)(page, wbc, data); | |
2470 | ||
2471 | if (unlikely(ret == AOP_WRITEPAGE_ACTIVATE)) { | |
2472 | unlock_page(page); | |
2473 | ret = 0; | |
2474 | } | |
771ed689 | 2475 | if (ret || wbc->nr_to_write <= 0) |
d1310b2e CM |
2476 | done = 1; |
2477 | if (wbc->nonblocking && bdi_write_congested(bdi)) { | |
2478 | wbc->encountered_congestion = 1; | |
2479 | done = 1; | |
2480 | } | |
2481 | } | |
2482 | pagevec_release(&pvec); | |
2483 | cond_resched(); | |
2484 | } | |
2485 | if (!scanned && !done) { | |
2486 | /* | |
2487 | * We hit the last page and there is more work to be done: wrap | |
2488 | * back to the start of the file | |
2489 | */ | |
2490 | scanned = 1; | |
2491 | index = 0; | |
2492 | goto retry; | |
2493 | } | |
d1310b2e CM |
2494 | return ret; |
2495 | } | |
d1310b2e | 2496 | |
d2c3f4f6 CM |
2497 | static noinline void flush_write_bio(void *data) |
2498 | { | |
2499 | struct extent_page_data *epd = data; | |
2500 | if (epd->bio) { | |
2501 | submit_one_bio(WRITE, epd->bio, 0, 0); | |
2502 | epd->bio = NULL; | |
2503 | } | |
2504 | } | |
2505 | ||
d1310b2e CM |
2506 | int extent_write_full_page(struct extent_io_tree *tree, struct page *page, |
2507 | get_extent_t *get_extent, | |
2508 | struct writeback_control *wbc) | |
2509 | { | |
2510 | int ret; | |
2511 | struct address_space *mapping = page->mapping; | |
2512 | struct extent_page_data epd = { | |
2513 | .bio = NULL, | |
2514 | .tree = tree, | |
2515 | .get_extent = get_extent, | |
771ed689 | 2516 | .extent_locked = 0, |
d1310b2e CM |
2517 | }; |
2518 | struct writeback_control wbc_writepages = { | |
2519 | .bdi = wbc->bdi, | |
2520 | .sync_mode = WB_SYNC_NONE, | |
2521 | .older_than_this = NULL, | |
2522 | .nr_to_write = 64, | |
2523 | .range_start = page_offset(page) + PAGE_CACHE_SIZE, | |
2524 | .range_end = (loff_t)-1, | |
2525 | }; | |
2526 | ||
2527 | ||
2528 | ret = __extent_writepage(page, wbc, &epd); | |
2529 | ||
4bef0848 | 2530 | extent_write_cache_pages(tree, mapping, &wbc_writepages, |
d2c3f4f6 | 2531 | __extent_writepage, &epd, flush_write_bio); |
d397712b | 2532 | if (epd.bio) |
c8b97818 | 2533 | submit_one_bio(WRITE, epd.bio, 0, 0); |
d1310b2e CM |
2534 | return ret; |
2535 | } | |
2536 | EXPORT_SYMBOL(extent_write_full_page); | |
2537 | ||
771ed689 CM |
2538 | int extent_write_locked_range(struct extent_io_tree *tree, struct inode *inode, |
2539 | u64 start, u64 end, get_extent_t *get_extent, | |
2540 | int mode) | |
2541 | { | |
2542 | int ret = 0; | |
2543 | struct address_space *mapping = inode->i_mapping; | |
2544 | struct page *page; | |
2545 | unsigned long nr_pages = (end - start + PAGE_CACHE_SIZE) >> | |
2546 | PAGE_CACHE_SHIFT; | |
2547 | ||
2548 | struct extent_page_data epd = { | |
2549 | .bio = NULL, | |
2550 | .tree = tree, | |
2551 | .get_extent = get_extent, | |
2552 | .extent_locked = 1, | |
2553 | }; | |
2554 | struct writeback_control wbc_writepages = { | |
2555 | .bdi = inode->i_mapping->backing_dev_info, | |
2556 | .sync_mode = mode, | |
2557 | .older_than_this = NULL, | |
2558 | .nr_to_write = nr_pages * 2, | |
2559 | .range_start = start, | |
2560 | .range_end = end + 1, | |
2561 | }; | |
2562 | ||
d397712b | 2563 | while (start <= end) { |
771ed689 CM |
2564 | page = find_get_page(mapping, start >> PAGE_CACHE_SHIFT); |
2565 | if (clear_page_dirty_for_io(page)) | |
2566 | ret = __extent_writepage(page, &wbc_writepages, &epd); | |
2567 | else { | |
2568 | if (tree->ops && tree->ops->writepage_end_io_hook) | |
2569 | tree->ops->writepage_end_io_hook(page, start, | |
2570 | start + PAGE_CACHE_SIZE - 1, | |
2571 | NULL, 1); | |
2572 | unlock_page(page); | |
2573 | } | |
2574 | page_cache_release(page); | |
2575 | start += PAGE_CACHE_SIZE; | |
2576 | } | |
2577 | ||
2578 | if (epd.bio) | |
2579 | submit_one_bio(WRITE, epd.bio, 0, 0); | |
2580 | return ret; | |
2581 | } | |
2582 | EXPORT_SYMBOL(extent_write_locked_range); | |
2583 | ||
d1310b2e CM |
2584 | |
2585 | int extent_writepages(struct extent_io_tree *tree, | |
2586 | struct address_space *mapping, | |
2587 | get_extent_t *get_extent, | |
2588 | struct writeback_control *wbc) | |
2589 | { | |
2590 | int ret = 0; | |
2591 | struct extent_page_data epd = { | |
2592 | .bio = NULL, | |
2593 | .tree = tree, | |
2594 | .get_extent = get_extent, | |
771ed689 | 2595 | .extent_locked = 0, |
d1310b2e CM |
2596 | }; |
2597 | ||
4bef0848 | 2598 | ret = extent_write_cache_pages(tree, mapping, wbc, |
d2c3f4f6 CM |
2599 | __extent_writepage, &epd, |
2600 | flush_write_bio); | |
d397712b | 2601 | if (epd.bio) |
c8b97818 | 2602 | submit_one_bio(WRITE, epd.bio, 0, 0); |
d1310b2e CM |
2603 | return ret; |
2604 | } | |
2605 | EXPORT_SYMBOL(extent_writepages); | |
2606 | ||
2607 | int extent_readpages(struct extent_io_tree *tree, | |
2608 | struct address_space *mapping, | |
2609 | struct list_head *pages, unsigned nr_pages, | |
2610 | get_extent_t get_extent) | |
2611 | { | |
2612 | struct bio *bio = NULL; | |
2613 | unsigned page_idx; | |
2614 | struct pagevec pvec; | |
c8b97818 | 2615 | unsigned long bio_flags = 0; |
d1310b2e CM |
2616 | |
2617 | pagevec_init(&pvec, 0); | |
2618 | for (page_idx = 0; page_idx < nr_pages; page_idx++) { | |
2619 | struct page *page = list_entry(pages->prev, struct page, lru); | |
2620 | ||
2621 | prefetchw(&page->flags); | |
2622 | list_del(&page->lru); | |
2623 | /* | |
2624 | * what we want to do here is call add_to_page_cache_lru, | |
2625 | * but that isn't exported, so we reproduce it here | |
2626 | */ | |
2627 | if (!add_to_page_cache(page, mapping, | |
2628 | page->index, GFP_KERNEL)) { | |
2629 | ||
2630 | /* open coding of lru_cache_add, also not exported */ | |
2631 | page_cache_get(page); | |
2632 | if (!pagevec_add(&pvec, page)) | |
15916de8 | 2633 | __pagevec_lru_add_file(&pvec); |
f188591e | 2634 | __extent_read_full_page(tree, page, get_extent, |
c8b97818 | 2635 | &bio, 0, &bio_flags); |
d1310b2e CM |
2636 | } |
2637 | page_cache_release(page); | |
2638 | } | |
2639 | if (pagevec_count(&pvec)) | |
15916de8 | 2640 | __pagevec_lru_add_file(&pvec); |
d1310b2e CM |
2641 | BUG_ON(!list_empty(pages)); |
2642 | if (bio) | |
c8b97818 | 2643 | submit_one_bio(READ, bio, 0, bio_flags); |
d1310b2e CM |
2644 | return 0; |
2645 | } | |
2646 | EXPORT_SYMBOL(extent_readpages); | |
2647 | ||
2648 | /* | |
2649 | * basic invalidatepage code, this waits on any locked or writeback | |
2650 | * ranges corresponding to the page, and then deletes any extent state | |
2651 | * records from the tree | |
2652 | */ | |
2653 | int extent_invalidatepage(struct extent_io_tree *tree, | |
2654 | struct page *page, unsigned long offset) | |
2655 | { | |
2656 | u64 start = ((u64)page->index << PAGE_CACHE_SHIFT); | |
2657 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
2658 | size_t blocksize = page->mapping->host->i_sb->s_blocksize; | |
2659 | ||
d397712b | 2660 | start += (offset + blocksize - 1) & ~(blocksize - 1); |
d1310b2e CM |
2661 | if (start > end) |
2662 | return 0; | |
2663 | ||
2664 | lock_extent(tree, start, end, GFP_NOFS); | |
2665 | wait_on_extent_writeback(tree, start, end); | |
2666 | clear_extent_bit(tree, start, end, | |
2667 | EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC, | |
2668 | 1, 1, GFP_NOFS); | |
2669 | return 0; | |
2670 | } | |
2671 | EXPORT_SYMBOL(extent_invalidatepage); | |
2672 | ||
2673 | /* | |
2674 | * simple commit_write call, set_range_dirty is used to mark both | |
2675 | * the pages and the extent records as dirty | |
2676 | */ | |
2677 | int extent_commit_write(struct extent_io_tree *tree, | |
2678 | struct inode *inode, struct page *page, | |
2679 | unsigned from, unsigned to) | |
2680 | { | |
2681 | loff_t pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to; | |
2682 | ||
2683 | set_page_extent_mapped(page); | |
2684 | set_page_dirty(page); | |
2685 | ||
2686 | if (pos > inode->i_size) { | |
2687 | i_size_write(inode, pos); | |
2688 | mark_inode_dirty(inode); | |
2689 | } | |
2690 | return 0; | |
2691 | } | |
2692 | EXPORT_SYMBOL(extent_commit_write); | |
2693 | ||
2694 | int extent_prepare_write(struct extent_io_tree *tree, | |
2695 | struct inode *inode, struct page *page, | |
2696 | unsigned from, unsigned to, get_extent_t *get_extent) | |
2697 | { | |
2698 | u64 page_start = (u64)page->index << PAGE_CACHE_SHIFT; | |
2699 | u64 page_end = page_start + PAGE_CACHE_SIZE - 1; | |
2700 | u64 block_start; | |
2701 | u64 orig_block_start; | |
2702 | u64 block_end; | |
2703 | u64 cur_end; | |
2704 | struct extent_map *em; | |
2705 | unsigned blocksize = 1 << inode->i_blkbits; | |
2706 | size_t page_offset = 0; | |
2707 | size_t block_off_start; | |
2708 | size_t block_off_end; | |
2709 | int err = 0; | |
2710 | int iocount = 0; | |
2711 | int ret = 0; | |
2712 | int isnew; | |
2713 | ||
2714 | set_page_extent_mapped(page); | |
2715 | ||
2716 | block_start = (page_start + from) & ~((u64)blocksize - 1); | |
2717 | block_end = (page_start + to - 1) | (blocksize - 1); | |
2718 | orig_block_start = block_start; | |
2719 | ||
2720 | lock_extent(tree, page_start, page_end, GFP_NOFS); | |
d397712b | 2721 | while (block_start <= block_end) { |
d1310b2e CM |
2722 | em = get_extent(inode, page, page_offset, block_start, |
2723 | block_end - block_start + 1, 1); | |
d397712b | 2724 | if (IS_ERR(em) || !em) |
d1310b2e | 2725 | goto err; |
d397712b | 2726 | |
d1310b2e CM |
2727 | cur_end = min(block_end, extent_map_end(em) - 1); |
2728 | block_off_start = block_start & (PAGE_CACHE_SIZE - 1); | |
2729 | block_off_end = block_off_start + blocksize; | |
2730 | isnew = clear_extent_new(tree, block_start, cur_end, GFP_NOFS); | |
2731 | ||
2732 | if (!PageUptodate(page) && isnew && | |
2733 | (block_off_end > to || block_off_start < from)) { | |
2734 | void *kaddr; | |
2735 | ||
2736 | kaddr = kmap_atomic(page, KM_USER0); | |
2737 | if (block_off_end > to) | |
2738 | memset(kaddr + to, 0, block_off_end - to); | |
2739 | if (block_off_start < from) | |
2740 | memset(kaddr + block_off_start, 0, | |
2741 | from - block_off_start); | |
2742 | flush_dcache_page(page); | |
2743 | kunmap_atomic(kaddr, KM_USER0); | |
2744 | } | |
2745 | if ((em->block_start != EXTENT_MAP_HOLE && | |
2746 | em->block_start != EXTENT_MAP_INLINE) && | |
2747 | !isnew && !PageUptodate(page) && | |
2748 | (block_off_end > to || block_off_start < from) && | |
2749 | !test_range_bit(tree, block_start, cur_end, | |
2750 | EXTENT_UPTODATE, 1)) { | |
2751 | u64 sector; | |
2752 | u64 extent_offset = block_start - em->start; | |
2753 | size_t iosize; | |
2754 | sector = (em->block_start + extent_offset) >> 9; | |
2755 | iosize = (cur_end - block_start + blocksize) & | |
2756 | ~((u64)blocksize - 1); | |
2757 | /* | |
2758 | * we've already got the extent locked, but we | |
2759 | * need to split the state such that our end_bio | |
2760 | * handler can clear the lock. | |
2761 | */ | |
2762 | set_extent_bit(tree, block_start, | |
2763 | block_start + iosize - 1, | |
2764 | EXTENT_LOCKED, 0, NULL, GFP_NOFS); | |
2765 | ret = submit_extent_page(READ, tree, page, | |
2766 | sector, iosize, page_offset, em->bdev, | |
2767 | NULL, 1, | |
c8b97818 CM |
2768 | end_bio_extent_preparewrite, 0, |
2769 | 0, 0); | |
d1310b2e CM |
2770 | iocount++; |
2771 | block_start = block_start + iosize; | |
2772 | } else { | |
2773 | set_extent_uptodate(tree, block_start, cur_end, | |
2774 | GFP_NOFS); | |
2775 | unlock_extent(tree, block_start, cur_end, GFP_NOFS); | |
2776 | block_start = cur_end + 1; | |
2777 | } | |
2778 | page_offset = block_start & (PAGE_CACHE_SIZE - 1); | |
2779 | free_extent_map(em); | |
2780 | } | |
2781 | if (iocount) { | |
2782 | wait_extent_bit(tree, orig_block_start, | |
2783 | block_end, EXTENT_LOCKED); | |
2784 | } | |
2785 | check_page_uptodate(tree, page); | |
2786 | err: | |
2787 | /* FIXME, zero out newly allocated blocks on error */ | |
2788 | return err; | |
2789 | } | |
2790 | EXPORT_SYMBOL(extent_prepare_write); | |
2791 | ||
7b13b7b1 CM |
2792 | /* |
2793 | * a helper for releasepage, this tests for areas of the page that | |
2794 | * are locked or under IO and drops the related state bits if it is safe | |
2795 | * to drop the page. | |
2796 | */ | |
2797 | int try_release_extent_state(struct extent_map_tree *map, | |
2798 | struct extent_io_tree *tree, struct page *page, | |
2799 | gfp_t mask) | |
2800 | { | |
2801 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
2802 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
2803 | int ret = 1; | |
2804 | ||
211f90e6 CM |
2805 | if (test_range_bit(tree, start, end, |
2806 | EXTENT_IOBITS | EXTENT_ORDERED, 0)) | |
7b13b7b1 CM |
2807 | ret = 0; |
2808 | else { | |
2809 | if ((mask & GFP_NOFS) == GFP_NOFS) | |
2810 | mask = GFP_NOFS; | |
2811 | clear_extent_bit(tree, start, end, EXTENT_UPTODATE, | |
2812 | 1, 1, mask); | |
2813 | } | |
2814 | return ret; | |
2815 | } | |
2816 | EXPORT_SYMBOL(try_release_extent_state); | |
2817 | ||
d1310b2e CM |
2818 | /* |
2819 | * a helper for releasepage. As long as there are no locked extents | |
2820 | * in the range corresponding to the page, both state records and extent | |
2821 | * map records are removed | |
2822 | */ | |
2823 | int try_release_extent_mapping(struct extent_map_tree *map, | |
70dec807 CM |
2824 | struct extent_io_tree *tree, struct page *page, |
2825 | gfp_t mask) | |
d1310b2e CM |
2826 | { |
2827 | struct extent_map *em; | |
2828 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
2829 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
7b13b7b1 | 2830 | |
70dec807 CM |
2831 | if ((mask & __GFP_WAIT) && |
2832 | page->mapping->host->i_size > 16 * 1024 * 1024) { | |
39b5637f | 2833 | u64 len; |
70dec807 | 2834 | while (start <= end) { |
39b5637f | 2835 | len = end - start + 1; |
70dec807 | 2836 | spin_lock(&map->lock); |
39b5637f | 2837 | em = lookup_extent_mapping(map, start, len); |
70dec807 CM |
2838 | if (!em || IS_ERR(em)) { |
2839 | spin_unlock(&map->lock); | |
2840 | break; | |
2841 | } | |
7f3c74fb CM |
2842 | if (test_bit(EXTENT_FLAG_PINNED, &em->flags) || |
2843 | em->start != start) { | |
70dec807 CM |
2844 | spin_unlock(&map->lock); |
2845 | free_extent_map(em); | |
2846 | break; | |
2847 | } | |
2848 | if (!test_range_bit(tree, em->start, | |
2849 | extent_map_end(em) - 1, | |
c8b97818 CM |
2850 | EXTENT_LOCKED | EXTENT_WRITEBACK | |
2851 | EXTENT_ORDERED, | |
2852 | 0)) { | |
70dec807 CM |
2853 | remove_extent_mapping(map, em); |
2854 | /* once for the rb tree */ | |
2855 | free_extent_map(em); | |
2856 | } | |
2857 | start = extent_map_end(em); | |
d1310b2e | 2858 | spin_unlock(&map->lock); |
70dec807 CM |
2859 | |
2860 | /* once for us */ | |
d1310b2e CM |
2861 | free_extent_map(em); |
2862 | } | |
d1310b2e | 2863 | } |
7b13b7b1 | 2864 | return try_release_extent_state(map, tree, page, mask); |
d1310b2e CM |
2865 | } |
2866 | EXPORT_SYMBOL(try_release_extent_mapping); | |
2867 | ||
2868 | sector_t extent_bmap(struct address_space *mapping, sector_t iblock, | |
2869 | get_extent_t *get_extent) | |
2870 | { | |
2871 | struct inode *inode = mapping->host; | |
2872 | u64 start = iblock << inode->i_blkbits; | |
2873 | sector_t sector = 0; | |
d899e052 | 2874 | size_t blksize = (1 << inode->i_blkbits); |
d1310b2e CM |
2875 | struct extent_map *em; |
2876 | ||
d899e052 YZ |
2877 | lock_extent(&BTRFS_I(inode)->io_tree, start, start + blksize - 1, |
2878 | GFP_NOFS); | |
2879 | em = get_extent(inode, NULL, 0, start, blksize, 0); | |
2880 | unlock_extent(&BTRFS_I(inode)->io_tree, start, start + blksize - 1, | |
2881 | GFP_NOFS); | |
d1310b2e CM |
2882 | if (!em || IS_ERR(em)) |
2883 | return 0; | |
2884 | ||
d899e052 | 2885 | if (em->block_start > EXTENT_MAP_LAST_BYTE) |
d1310b2e CM |
2886 | goto out; |
2887 | ||
2888 | sector = (em->block_start + start - em->start) >> inode->i_blkbits; | |
d1310b2e CM |
2889 | out: |
2890 | free_extent_map(em); | |
2891 | return sector; | |
2892 | } | |
2893 | ||
d1310b2e CM |
2894 | static inline struct page *extent_buffer_page(struct extent_buffer *eb, |
2895 | unsigned long i) | |
2896 | { | |
2897 | struct page *p; | |
2898 | struct address_space *mapping; | |
2899 | ||
2900 | if (i == 0) | |
2901 | return eb->first_page; | |
2902 | i += eb->start >> PAGE_CACHE_SHIFT; | |
2903 | mapping = eb->first_page->mapping; | |
33958dc6 CM |
2904 | if (!mapping) |
2905 | return NULL; | |
0ee0fda0 SW |
2906 | |
2907 | /* | |
2908 | * extent_buffer_page is only called after pinning the page | |
2909 | * by increasing the reference count. So we know the page must | |
2910 | * be in the radix tree. | |
2911 | */ | |
0ee0fda0 | 2912 | rcu_read_lock(); |
d1310b2e | 2913 | p = radix_tree_lookup(&mapping->page_tree, i); |
0ee0fda0 | 2914 | rcu_read_unlock(); |
2b1f55b0 | 2915 | |
d1310b2e CM |
2916 | return p; |
2917 | } | |
2918 | ||
6af118ce | 2919 | static inline unsigned long num_extent_pages(u64 start, u64 len) |
728131d8 | 2920 | { |
6af118ce CM |
2921 | return ((start + len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT) - |
2922 | (start >> PAGE_CACHE_SHIFT); | |
728131d8 CM |
2923 | } |
2924 | ||
d1310b2e CM |
2925 | static struct extent_buffer *__alloc_extent_buffer(struct extent_io_tree *tree, |
2926 | u64 start, | |
2927 | unsigned long len, | |
2928 | gfp_t mask) | |
2929 | { | |
2930 | struct extent_buffer *eb = NULL; | |
4bef0848 | 2931 | #ifdef LEAK_DEBUG |
2d2ae547 | 2932 | unsigned long flags; |
4bef0848 | 2933 | #endif |
d1310b2e | 2934 | |
d1310b2e | 2935 | eb = kmem_cache_zalloc(extent_buffer_cache, mask); |
d1310b2e CM |
2936 | eb->start = start; |
2937 | eb->len = len; | |
a61e6f29 | 2938 | mutex_init(&eb->mutex); |
4bef0848 | 2939 | #ifdef LEAK_DEBUG |
2d2ae547 CM |
2940 | spin_lock_irqsave(&leak_lock, flags); |
2941 | list_add(&eb->leak_list, &buffers); | |
2942 | spin_unlock_irqrestore(&leak_lock, flags); | |
4bef0848 | 2943 | #endif |
d1310b2e CM |
2944 | atomic_set(&eb->refs, 1); |
2945 | ||
2946 | return eb; | |
2947 | } | |
2948 | ||
2949 | static void __free_extent_buffer(struct extent_buffer *eb) | |
2950 | { | |
4bef0848 | 2951 | #ifdef LEAK_DEBUG |
2d2ae547 CM |
2952 | unsigned long flags; |
2953 | spin_lock_irqsave(&leak_lock, flags); | |
2954 | list_del(&eb->leak_list); | |
2955 | spin_unlock_irqrestore(&leak_lock, flags); | |
4bef0848 | 2956 | #endif |
d1310b2e CM |
2957 | kmem_cache_free(extent_buffer_cache, eb); |
2958 | } | |
2959 | ||
2960 | struct extent_buffer *alloc_extent_buffer(struct extent_io_tree *tree, | |
2961 | u64 start, unsigned long len, | |
2962 | struct page *page0, | |
2963 | gfp_t mask) | |
2964 | { | |
2965 | unsigned long num_pages = num_extent_pages(start, len); | |
2966 | unsigned long i; | |
2967 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
2968 | struct extent_buffer *eb; | |
6af118ce | 2969 | struct extent_buffer *exists = NULL; |
d1310b2e CM |
2970 | struct page *p; |
2971 | struct address_space *mapping = tree->mapping; | |
2972 | int uptodate = 1; | |
2973 | ||
6af118ce CM |
2974 | spin_lock(&tree->buffer_lock); |
2975 | eb = buffer_search(tree, start); | |
2976 | if (eb) { | |
2977 | atomic_inc(&eb->refs); | |
2978 | spin_unlock(&tree->buffer_lock); | |
0f9dd46c | 2979 | mark_page_accessed(eb->first_page); |
6af118ce CM |
2980 | return eb; |
2981 | } | |
2982 | spin_unlock(&tree->buffer_lock); | |
2983 | ||
d1310b2e | 2984 | eb = __alloc_extent_buffer(tree, start, len, mask); |
2b114d1d | 2985 | if (!eb) |
d1310b2e CM |
2986 | return NULL; |
2987 | ||
d1310b2e CM |
2988 | if (page0) { |
2989 | eb->first_page = page0; | |
2990 | i = 1; | |
2991 | index++; | |
2992 | page_cache_get(page0); | |
2993 | mark_page_accessed(page0); | |
2994 | set_page_extent_mapped(page0); | |
d1310b2e | 2995 | set_page_extent_head(page0, len); |
f188591e | 2996 | uptodate = PageUptodate(page0); |
d1310b2e CM |
2997 | } else { |
2998 | i = 0; | |
2999 | } | |
3000 | for (; i < num_pages; i++, index++) { | |
3001 | p = find_or_create_page(mapping, index, mask | __GFP_HIGHMEM); | |
3002 | if (!p) { | |
3003 | WARN_ON(1); | |
6af118ce | 3004 | goto free_eb; |
d1310b2e CM |
3005 | } |
3006 | set_page_extent_mapped(p); | |
3007 | mark_page_accessed(p); | |
3008 | if (i == 0) { | |
3009 | eb->first_page = p; | |
3010 | set_page_extent_head(p, len); | |
3011 | } else { | |
3012 | set_page_private(p, EXTENT_PAGE_PRIVATE); | |
3013 | } | |
3014 | if (!PageUptodate(p)) | |
3015 | uptodate = 0; | |
3016 | unlock_page(p); | |
3017 | } | |
3018 | if (uptodate) | |
3019 | eb->flags |= EXTENT_UPTODATE; | |
3020 | eb->flags |= EXTENT_BUFFER_FILLED; | |
3021 | ||
6af118ce CM |
3022 | spin_lock(&tree->buffer_lock); |
3023 | exists = buffer_tree_insert(tree, start, &eb->rb_node); | |
3024 | if (exists) { | |
3025 | /* add one reference for the caller */ | |
3026 | atomic_inc(&exists->refs); | |
3027 | spin_unlock(&tree->buffer_lock); | |
3028 | goto free_eb; | |
3029 | } | |
3030 | spin_unlock(&tree->buffer_lock); | |
3031 | ||
3032 | /* add one reference for the tree */ | |
3033 | atomic_inc(&eb->refs); | |
d1310b2e CM |
3034 | return eb; |
3035 | ||
6af118ce | 3036 | free_eb: |
d1310b2e | 3037 | if (!atomic_dec_and_test(&eb->refs)) |
6af118ce CM |
3038 | return exists; |
3039 | for (index = 1; index < i; index++) | |
d1310b2e | 3040 | page_cache_release(extent_buffer_page(eb, index)); |
6af118ce | 3041 | page_cache_release(extent_buffer_page(eb, 0)); |
d1310b2e | 3042 | __free_extent_buffer(eb); |
6af118ce | 3043 | return exists; |
d1310b2e CM |
3044 | } |
3045 | EXPORT_SYMBOL(alloc_extent_buffer); | |
3046 | ||
3047 | struct extent_buffer *find_extent_buffer(struct extent_io_tree *tree, | |
3048 | u64 start, unsigned long len, | |
3049 | gfp_t mask) | |
3050 | { | |
d1310b2e | 3051 | struct extent_buffer *eb; |
d1310b2e | 3052 | |
6af118ce CM |
3053 | spin_lock(&tree->buffer_lock); |
3054 | eb = buffer_search(tree, start); | |
3055 | if (eb) | |
3056 | atomic_inc(&eb->refs); | |
3057 | spin_unlock(&tree->buffer_lock); | |
d1310b2e | 3058 | |
0f9dd46c JB |
3059 | if (eb) |
3060 | mark_page_accessed(eb->first_page); | |
3061 | ||
d1310b2e | 3062 | return eb; |
d1310b2e CM |
3063 | } |
3064 | EXPORT_SYMBOL(find_extent_buffer); | |
3065 | ||
3066 | void free_extent_buffer(struct extent_buffer *eb) | |
3067 | { | |
d1310b2e CM |
3068 | if (!eb) |
3069 | return; | |
3070 | ||
3071 | if (!atomic_dec_and_test(&eb->refs)) | |
3072 | return; | |
3073 | ||
6af118ce | 3074 | WARN_ON(1); |
d1310b2e CM |
3075 | } |
3076 | EXPORT_SYMBOL(free_extent_buffer); | |
3077 | ||
3078 | int clear_extent_buffer_dirty(struct extent_io_tree *tree, | |
3079 | struct extent_buffer *eb) | |
3080 | { | |
3081 | int set; | |
3082 | unsigned long i; | |
3083 | unsigned long num_pages; | |
3084 | struct page *page; | |
3085 | ||
3086 | u64 start = eb->start; | |
3087 | u64 end = start + eb->len - 1; | |
3088 | ||
3089 | set = clear_extent_dirty(tree, start, end, GFP_NOFS); | |
3090 | num_pages = num_extent_pages(eb->start, eb->len); | |
3091 | ||
3092 | for (i = 0; i < num_pages; i++) { | |
3093 | page = extent_buffer_page(eb, i); | |
d2c3f4f6 CM |
3094 | if (!set && !PageDirty(page)) |
3095 | continue; | |
3096 | ||
a61e6f29 | 3097 | lock_page(page); |
d1310b2e CM |
3098 | if (i == 0) |
3099 | set_page_extent_head(page, eb->len); | |
3100 | else | |
3101 | set_page_private(page, EXTENT_PAGE_PRIVATE); | |
3102 | ||
3103 | /* | |
3104 | * if we're on the last page or the first page and the | |
3105 | * block isn't aligned on a page boundary, do extra checks | |
3106 | * to make sure we don't clean page that is partially dirty | |
3107 | */ | |
3108 | if ((i == 0 && (eb->start & (PAGE_CACHE_SIZE - 1))) || | |
3109 | ((i == num_pages - 1) && | |
3110 | ((eb->start + eb->len) & (PAGE_CACHE_SIZE - 1)))) { | |
3111 | start = (u64)page->index << PAGE_CACHE_SHIFT; | |
3112 | end = start + PAGE_CACHE_SIZE - 1; | |
3113 | if (test_range_bit(tree, start, end, | |
3114 | EXTENT_DIRTY, 0)) { | |
a61e6f29 | 3115 | unlock_page(page); |
d1310b2e CM |
3116 | continue; |
3117 | } | |
3118 | } | |
3119 | clear_page_dirty_for_io(page); | |
0ee0fda0 | 3120 | spin_lock_irq(&page->mapping->tree_lock); |
d1310b2e CM |
3121 | if (!PageDirty(page)) { |
3122 | radix_tree_tag_clear(&page->mapping->page_tree, | |
3123 | page_index(page), | |
3124 | PAGECACHE_TAG_DIRTY); | |
3125 | } | |
0ee0fda0 | 3126 | spin_unlock_irq(&page->mapping->tree_lock); |
a61e6f29 | 3127 | unlock_page(page); |
d1310b2e CM |
3128 | } |
3129 | return 0; | |
3130 | } | |
3131 | EXPORT_SYMBOL(clear_extent_buffer_dirty); | |
3132 | ||
3133 | int wait_on_extent_buffer_writeback(struct extent_io_tree *tree, | |
3134 | struct extent_buffer *eb) | |
3135 | { | |
3136 | return wait_on_extent_writeback(tree, eb->start, | |
3137 | eb->start + eb->len - 1); | |
3138 | } | |
3139 | EXPORT_SYMBOL(wait_on_extent_buffer_writeback); | |
3140 | ||
3141 | int set_extent_buffer_dirty(struct extent_io_tree *tree, | |
3142 | struct extent_buffer *eb) | |
3143 | { | |
3144 | unsigned long i; | |
3145 | unsigned long num_pages; | |
3146 | ||
3147 | num_pages = num_extent_pages(eb->start, eb->len); | |
3148 | for (i = 0; i < num_pages; i++) { | |
3149 | struct page *page = extent_buffer_page(eb, i); | |
3150 | /* writepage may need to do something special for the | |
3151 | * first page, we have to make sure page->private is | |
3152 | * properly set. releasepage may drop page->private | |
3153 | * on us if the page isn't already dirty. | |
3154 | */ | |
a1b32a59 | 3155 | lock_page(page); |
d1310b2e | 3156 | if (i == 0) { |
d1310b2e CM |
3157 | set_page_extent_head(page, eb->len); |
3158 | } else if (PagePrivate(page) && | |
3159 | page->private != EXTENT_PAGE_PRIVATE) { | |
d1310b2e | 3160 | set_page_extent_mapped(page); |
d1310b2e CM |
3161 | } |
3162 | __set_page_dirty_nobuffers(extent_buffer_page(eb, i)); | |
a1b32a59 | 3163 | set_extent_dirty(tree, page_offset(page), |
d397712b | 3164 | page_offset(page) + PAGE_CACHE_SIZE - 1, |
a1b32a59 CM |
3165 | GFP_NOFS); |
3166 | unlock_page(page); | |
d1310b2e | 3167 | } |
a1b32a59 | 3168 | return 0; |
d1310b2e CM |
3169 | } |
3170 | EXPORT_SYMBOL(set_extent_buffer_dirty); | |
3171 | ||
1259ab75 CM |
3172 | int clear_extent_buffer_uptodate(struct extent_io_tree *tree, |
3173 | struct extent_buffer *eb) | |
3174 | { | |
3175 | unsigned long i; | |
3176 | struct page *page; | |
3177 | unsigned long num_pages; | |
3178 | ||
3179 | num_pages = num_extent_pages(eb->start, eb->len); | |
3180 | eb->flags &= ~EXTENT_UPTODATE; | |
3181 | ||
3182 | clear_extent_uptodate(tree, eb->start, eb->start + eb->len - 1, | |
3183 | GFP_NOFS); | |
3184 | for (i = 0; i < num_pages; i++) { | |
3185 | page = extent_buffer_page(eb, i); | |
33958dc6 CM |
3186 | if (page) |
3187 | ClearPageUptodate(page); | |
1259ab75 CM |
3188 | } |
3189 | return 0; | |
3190 | } | |
3191 | ||
d1310b2e CM |
3192 | int set_extent_buffer_uptodate(struct extent_io_tree *tree, |
3193 | struct extent_buffer *eb) | |
3194 | { | |
3195 | unsigned long i; | |
3196 | struct page *page; | |
3197 | unsigned long num_pages; | |
3198 | ||
3199 | num_pages = num_extent_pages(eb->start, eb->len); | |
3200 | ||
3201 | set_extent_uptodate(tree, eb->start, eb->start + eb->len - 1, | |
3202 | GFP_NOFS); | |
3203 | for (i = 0; i < num_pages; i++) { | |
3204 | page = extent_buffer_page(eb, i); | |
3205 | if ((i == 0 && (eb->start & (PAGE_CACHE_SIZE - 1))) || | |
3206 | ((i == num_pages - 1) && | |
3207 | ((eb->start + eb->len) & (PAGE_CACHE_SIZE - 1)))) { | |
3208 | check_page_uptodate(tree, page); | |
3209 | continue; | |
3210 | } | |
3211 | SetPageUptodate(page); | |
3212 | } | |
3213 | return 0; | |
3214 | } | |
3215 | EXPORT_SYMBOL(set_extent_buffer_uptodate); | |
3216 | ||
ce9adaa5 CM |
3217 | int extent_range_uptodate(struct extent_io_tree *tree, |
3218 | u64 start, u64 end) | |
3219 | { | |
3220 | struct page *page; | |
3221 | int ret; | |
3222 | int pg_uptodate = 1; | |
3223 | int uptodate; | |
3224 | unsigned long index; | |
3225 | ||
3226 | ret = test_range_bit(tree, start, end, EXTENT_UPTODATE, 1); | |
3227 | if (ret) | |
3228 | return 1; | |
d397712b | 3229 | while (start <= end) { |
ce9adaa5 CM |
3230 | index = start >> PAGE_CACHE_SHIFT; |
3231 | page = find_get_page(tree->mapping, index); | |
3232 | uptodate = PageUptodate(page); | |
3233 | page_cache_release(page); | |
3234 | if (!uptodate) { | |
3235 | pg_uptodate = 0; | |
3236 | break; | |
3237 | } | |
3238 | start += PAGE_CACHE_SIZE; | |
3239 | } | |
3240 | return pg_uptodate; | |
3241 | } | |
3242 | ||
d1310b2e | 3243 | int extent_buffer_uptodate(struct extent_io_tree *tree, |
ce9adaa5 | 3244 | struct extent_buffer *eb) |
d1310b2e | 3245 | { |
728131d8 | 3246 | int ret = 0; |
ce9adaa5 CM |
3247 | unsigned long num_pages; |
3248 | unsigned long i; | |
728131d8 CM |
3249 | struct page *page; |
3250 | int pg_uptodate = 1; | |
3251 | ||
d1310b2e | 3252 | if (eb->flags & EXTENT_UPTODATE) |
4235298e | 3253 | return 1; |
728131d8 | 3254 | |
4235298e | 3255 | ret = test_range_bit(tree, eb->start, eb->start + eb->len - 1, |
d1310b2e | 3256 | EXTENT_UPTODATE, 1); |
4235298e CM |
3257 | if (ret) |
3258 | return ret; | |
728131d8 CM |
3259 | |
3260 | num_pages = num_extent_pages(eb->start, eb->len); | |
3261 | for (i = 0; i < num_pages; i++) { | |
3262 | page = extent_buffer_page(eb, i); | |
3263 | if (!PageUptodate(page)) { | |
3264 | pg_uptodate = 0; | |
3265 | break; | |
3266 | } | |
3267 | } | |
4235298e | 3268 | return pg_uptodate; |
d1310b2e CM |
3269 | } |
3270 | EXPORT_SYMBOL(extent_buffer_uptodate); | |
3271 | ||
3272 | int read_extent_buffer_pages(struct extent_io_tree *tree, | |
3273 | struct extent_buffer *eb, | |
a86c12c7 | 3274 | u64 start, int wait, |
f188591e | 3275 | get_extent_t *get_extent, int mirror_num) |
d1310b2e CM |
3276 | { |
3277 | unsigned long i; | |
3278 | unsigned long start_i; | |
3279 | struct page *page; | |
3280 | int err; | |
3281 | int ret = 0; | |
ce9adaa5 CM |
3282 | int locked_pages = 0; |
3283 | int all_uptodate = 1; | |
3284 | int inc_all_pages = 0; | |
d1310b2e | 3285 | unsigned long num_pages; |
a86c12c7 | 3286 | struct bio *bio = NULL; |
c8b97818 | 3287 | unsigned long bio_flags = 0; |
a86c12c7 | 3288 | |
d1310b2e CM |
3289 | if (eb->flags & EXTENT_UPTODATE) |
3290 | return 0; | |
3291 | ||
ce9adaa5 | 3292 | if (test_range_bit(tree, eb->start, eb->start + eb->len - 1, |
d1310b2e CM |
3293 | EXTENT_UPTODATE, 1)) { |
3294 | return 0; | |
3295 | } | |
3296 | ||
3297 | if (start) { | |
3298 | WARN_ON(start < eb->start); | |
3299 | start_i = (start >> PAGE_CACHE_SHIFT) - | |
3300 | (eb->start >> PAGE_CACHE_SHIFT); | |
3301 | } else { | |
3302 | start_i = 0; | |
3303 | } | |
3304 | ||
3305 | num_pages = num_extent_pages(eb->start, eb->len); | |
3306 | for (i = start_i; i < num_pages; i++) { | |
3307 | page = extent_buffer_page(eb, i); | |
d1310b2e | 3308 | if (!wait) { |
2db04966 | 3309 | if (!trylock_page(page)) |
ce9adaa5 | 3310 | goto unlock_exit; |
d1310b2e CM |
3311 | } else { |
3312 | lock_page(page); | |
3313 | } | |
ce9adaa5 | 3314 | locked_pages++; |
d397712b | 3315 | if (!PageUptodate(page)) |
ce9adaa5 | 3316 | all_uptodate = 0; |
ce9adaa5 CM |
3317 | } |
3318 | if (all_uptodate) { | |
3319 | if (start_i == 0) | |
3320 | eb->flags |= EXTENT_UPTODATE; | |
3321 | goto unlock_exit; | |
3322 | } | |
3323 | ||
3324 | for (i = start_i; i < num_pages; i++) { | |
3325 | page = extent_buffer_page(eb, i); | |
3326 | if (inc_all_pages) | |
3327 | page_cache_get(page); | |
3328 | if (!PageUptodate(page)) { | |
3329 | if (start_i == 0) | |
3330 | inc_all_pages = 1; | |
f188591e | 3331 | ClearPageError(page); |
a86c12c7 | 3332 | err = __extent_read_full_page(tree, page, |
f188591e | 3333 | get_extent, &bio, |
c8b97818 | 3334 | mirror_num, &bio_flags); |
d397712b | 3335 | if (err) |
d1310b2e | 3336 | ret = err; |
d1310b2e CM |
3337 | } else { |
3338 | unlock_page(page); | |
3339 | } | |
3340 | } | |
3341 | ||
a86c12c7 | 3342 | if (bio) |
c8b97818 | 3343 | submit_one_bio(READ, bio, mirror_num, bio_flags); |
a86c12c7 | 3344 | |
d397712b | 3345 | if (ret || !wait) |
d1310b2e | 3346 | return ret; |
d397712b | 3347 | |
d1310b2e CM |
3348 | for (i = start_i; i < num_pages; i++) { |
3349 | page = extent_buffer_page(eb, i); | |
3350 | wait_on_page_locked(page); | |
d397712b | 3351 | if (!PageUptodate(page)) |
d1310b2e | 3352 | ret = -EIO; |
d1310b2e | 3353 | } |
d397712b | 3354 | |
d1310b2e CM |
3355 | if (!ret) |
3356 | eb->flags |= EXTENT_UPTODATE; | |
3357 | return ret; | |
ce9adaa5 CM |
3358 | |
3359 | unlock_exit: | |
3360 | i = start_i; | |
d397712b | 3361 | while (locked_pages > 0) { |
ce9adaa5 CM |
3362 | page = extent_buffer_page(eb, i); |
3363 | i++; | |
3364 | unlock_page(page); | |
3365 | locked_pages--; | |
3366 | } | |
3367 | return ret; | |
d1310b2e CM |
3368 | } |
3369 | EXPORT_SYMBOL(read_extent_buffer_pages); | |
3370 | ||
3371 | void read_extent_buffer(struct extent_buffer *eb, void *dstv, | |
3372 | unsigned long start, | |
3373 | unsigned long len) | |
3374 | { | |
3375 | size_t cur; | |
3376 | size_t offset; | |
3377 | struct page *page; | |
3378 | char *kaddr; | |
3379 | char *dst = (char *)dstv; | |
3380 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3381 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
d1310b2e CM |
3382 | |
3383 | WARN_ON(start > eb->len); | |
3384 | WARN_ON(start + len > eb->start + eb->len); | |
3385 | ||
3386 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3387 | ||
d397712b | 3388 | while (len > 0) { |
d1310b2e | 3389 | page = extent_buffer_page(eb, i); |
d1310b2e CM |
3390 | |
3391 | cur = min(len, (PAGE_CACHE_SIZE - offset)); | |
3392 | kaddr = kmap_atomic(page, KM_USER1); | |
3393 | memcpy(dst, kaddr + offset, cur); | |
3394 | kunmap_atomic(kaddr, KM_USER1); | |
3395 | ||
3396 | dst += cur; | |
3397 | len -= cur; | |
3398 | offset = 0; | |
3399 | i++; | |
3400 | } | |
3401 | } | |
3402 | EXPORT_SYMBOL(read_extent_buffer); | |
3403 | ||
3404 | int map_private_extent_buffer(struct extent_buffer *eb, unsigned long start, | |
3405 | unsigned long min_len, char **token, char **map, | |
3406 | unsigned long *map_start, | |
3407 | unsigned long *map_len, int km) | |
3408 | { | |
3409 | size_t offset = start & (PAGE_CACHE_SIZE - 1); | |
3410 | char *kaddr; | |
3411 | struct page *p; | |
3412 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3413 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
3414 | unsigned long end_i = (start_offset + start + min_len - 1) >> | |
3415 | PAGE_CACHE_SHIFT; | |
3416 | ||
3417 | if (i != end_i) | |
3418 | return -EINVAL; | |
3419 | ||
3420 | if (i == 0) { | |
3421 | offset = start_offset; | |
3422 | *map_start = 0; | |
3423 | } else { | |
3424 | offset = 0; | |
3425 | *map_start = ((u64)i << PAGE_CACHE_SHIFT) - start_offset; | |
3426 | } | |
d397712b | 3427 | |
d1310b2e | 3428 | if (start + min_len > eb->len) { |
d397712b CM |
3429 | printk(KERN_ERR "btrfs bad mapping eb start %llu len %lu, " |
3430 | "wanted %lu %lu\n", (unsigned long long)eb->start, | |
3431 | eb->len, start, min_len); | |
d1310b2e CM |
3432 | WARN_ON(1); |
3433 | } | |
3434 | ||
3435 | p = extent_buffer_page(eb, i); | |
d1310b2e CM |
3436 | kaddr = kmap_atomic(p, km); |
3437 | *token = kaddr; | |
3438 | *map = kaddr + offset; | |
3439 | *map_len = PAGE_CACHE_SIZE - offset; | |
3440 | return 0; | |
3441 | } | |
3442 | EXPORT_SYMBOL(map_private_extent_buffer); | |
3443 | ||
3444 | int map_extent_buffer(struct extent_buffer *eb, unsigned long start, | |
3445 | unsigned long min_len, | |
3446 | char **token, char **map, | |
3447 | unsigned long *map_start, | |
3448 | unsigned long *map_len, int km) | |
3449 | { | |
3450 | int err; | |
3451 | int save = 0; | |
3452 | if (eb->map_token) { | |
3453 | unmap_extent_buffer(eb, eb->map_token, km); | |
3454 | eb->map_token = NULL; | |
3455 | save = 1; | |
934d375b | 3456 | WARN_ON(!mutex_is_locked(&eb->mutex)); |
d1310b2e CM |
3457 | } |
3458 | err = map_private_extent_buffer(eb, start, min_len, token, map, | |
3459 | map_start, map_len, km); | |
3460 | if (!err && save) { | |
3461 | eb->map_token = *token; | |
3462 | eb->kaddr = *map; | |
3463 | eb->map_start = *map_start; | |
3464 | eb->map_len = *map_len; | |
3465 | } | |
3466 | return err; | |
3467 | } | |
3468 | EXPORT_SYMBOL(map_extent_buffer); | |
3469 | ||
3470 | void unmap_extent_buffer(struct extent_buffer *eb, char *token, int km) | |
3471 | { | |
3472 | kunmap_atomic(token, km); | |
3473 | } | |
3474 | EXPORT_SYMBOL(unmap_extent_buffer); | |
3475 | ||
3476 | int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv, | |
3477 | unsigned long start, | |
3478 | unsigned long len) | |
3479 | { | |
3480 | size_t cur; | |
3481 | size_t offset; | |
3482 | struct page *page; | |
3483 | char *kaddr; | |
3484 | char *ptr = (char *)ptrv; | |
3485 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3486 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
3487 | int ret = 0; | |
3488 | ||
3489 | WARN_ON(start > eb->len); | |
3490 | WARN_ON(start + len > eb->start + eb->len); | |
3491 | ||
3492 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3493 | ||
d397712b | 3494 | while (len > 0) { |
d1310b2e | 3495 | page = extent_buffer_page(eb, i); |
d1310b2e CM |
3496 | |
3497 | cur = min(len, (PAGE_CACHE_SIZE - offset)); | |
3498 | ||
3499 | kaddr = kmap_atomic(page, KM_USER0); | |
3500 | ret = memcmp(ptr, kaddr + offset, cur); | |
3501 | kunmap_atomic(kaddr, KM_USER0); | |
3502 | if (ret) | |
3503 | break; | |
3504 | ||
3505 | ptr += cur; | |
3506 | len -= cur; | |
3507 | offset = 0; | |
3508 | i++; | |
3509 | } | |
3510 | return ret; | |
3511 | } | |
3512 | EXPORT_SYMBOL(memcmp_extent_buffer); | |
3513 | ||
3514 | void write_extent_buffer(struct extent_buffer *eb, const void *srcv, | |
3515 | unsigned long start, unsigned long len) | |
3516 | { | |
3517 | size_t cur; | |
3518 | size_t offset; | |
3519 | struct page *page; | |
3520 | char *kaddr; | |
3521 | char *src = (char *)srcv; | |
3522 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3523 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
3524 | ||
3525 | WARN_ON(start > eb->len); | |
3526 | WARN_ON(start + len > eb->start + eb->len); | |
3527 | ||
3528 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3529 | ||
d397712b | 3530 | while (len > 0) { |
d1310b2e CM |
3531 | page = extent_buffer_page(eb, i); |
3532 | WARN_ON(!PageUptodate(page)); | |
3533 | ||
3534 | cur = min(len, PAGE_CACHE_SIZE - offset); | |
3535 | kaddr = kmap_atomic(page, KM_USER1); | |
3536 | memcpy(kaddr + offset, src, cur); | |
3537 | kunmap_atomic(kaddr, KM_USER1); | |
3538 | ||
3539 | src += cur; | |
3540 | len -= cur; | |
3541 | offset = 0; | |
3542 | i++; | |
3543 | } | |
3544 | } | |
3545 | EXPORT_SYMBOL(write_extent_buffer); | |
3546 | ||
3547 | void memset_extent_buffer(struct extent_buffer *eb, char c, | |
3548 | unsigned long start, unsigned long len) | |
3549 | { | |
3550 | size_t cur; | |
3551 | size_t offset; | |
3552 | struct page *page; | |
3553 | char *kaddr; | |
3554 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3555 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
3556 | ||
3557 | WARN_ON(start > eb->len); | |
3558 | WARN_ON(start + len > eb->start + eb->len); | |
3559 | ||
3560 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3561 | ||
d397712b | 3562 | while (len > 0) { |
d1310b2e CM |
3563 | page = extent_buffer_page(eb, i); |
3564 | WARN_ON(!PageUptodate(page)); | |
3565 | ||
3566 | cur = min(len, PAGE_CACHE_SIZE - offset); | |
3567 | kaddr = kmap_atomic(page, KM_USER0); | |
3568 | memset(kaddr + offset, c, cur); | |
3569 | kunmap_atomic(kaddr, KM_USER0); | |
3570 | ||
3571 | len -= cur; | |
3572 | offset = 0; | |
3573 | i++; | |
3574 | } | |
3575 | } | |
3576 | EXPORT_SYMBOL(memset_extent_buffer); | |
3577 | ||
3578 | void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src, | |
3579 | unsigned long dst_offset, unsigned long src_offset, | |
3580 | unsigned long len) | |
3581 | { | |
3582 | u64 dst_len = dst->len; | |
3583 | size_t cur; | |
3584 | size_t offset; | |
3585 | struct page *page; | |
3586 | char *kaddr; | |
3587 | size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3588 | unsigned long i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT; | |
3589 | ||
3590 | WARN_ON(src->len != dst_len); | |
3591 | ||
3592 | offset = (start_offset + dst_offset) & | |
3593 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3594 | ||
d397712b | 3595 | while (len > 0) { |
d1310b2e CM |
3596 | page = extent_buffer_page(dst, i); |
3597 | WARN_ON(!PageUptodate(page)); | |
3598 | ||
3599 | cur = min(len, (unsigned long)(PAGE_CACHE_SIZE - offset)); | |
3600 | ||
3601 | kaddr = kmap_atomic(page, KM_USER0); | |
3602 | read_extent_buffer(src, kaddr + offset, src_offset, cur); | |
3603 | kunmap_atomic(kaddr, KM_USER0); | |
3604 | ||
3605 | src_offset += cur; | |
3606 | len -= cur; | |
3607 | offset = 0; | |
3608 | i++; | |
3609 | } | |
3610 | } | |
3611 | EXPORT_SYMBOL(copy_extent_buffer); | |
3612 | ||
3613 | static void move_pages(struct page *dst_page, struct page *src_page, | |
3614 | unsigned long dst_off, unsigned long src_off, | |
3615 | unsigned long len) | |
3616 | { | |
3617 | char *dst_kaddr = kmap_atomic(dst_page, KM_USER0); | |
3618 | if (dst_page == src_page) { | |
3619 | memmove(dst_kaddr + dst_off, dst_kaddr + src_off, len); | |
3620 | } else { | |
3621 | char *src_kaddr = kmap_atomic(src_page, KM_USER1); | |
3622 | char *p = dst_kaddr + dst_off + len; | |
3623 | char *s = src_kaddr + src_off + len; | |
3624 | ||
3625 | while (len--) | |
3626 | *--p = *--s; | |
3627 | ||
3628 | kunmap_atomic(src_kaddr, KM_USER1); | |
3629 | } | |
3630 | kunmap_atomic(dst_kaddr, KM_USER0); | |
3631 | } | |
3632 | ||
3633 | static void copy_pages(struct page *dst_page, struct page *src_page, | |
3634 | unsigned long dst_off, unsigned long src_off, | |
3635 | unsigned long len) | |
3636 | { | |
3637 | char *dst_kaddr = kmap_atomic(dst_page, KM_USER0); | |
3638 | char *src_kaddr; | |
3639 | ||
3640 | if (dst_page != src_page) | |
3641 | src_kaddr = kmap_atomic(src_page, KM_USER1); | |
3642 | else | |
3643 | src_kaddr = dst_kaddr; | |
3644 | ||
3645 | memcpy(dst_kaddr + dst_off, src_kaddr + src_off, len); | |
3646 | kunmap_atomic(dst_kaddr, KM_USER0); | |
3647 | if (dst_page != src_page) | |
3648 | kunmap_atomic(src_kaddr, KM_USER1); | |
3649 | } | |
3650 | ||
3651 | void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, | |
3652 | unsigned long src_offset, unsigned long len) | |
3653 | { | |
3654 | size_t cur; | |
3655 | size_t dst_off_in_page; | |
3656 | size_t src_off_in_page; | |
3657 | size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3658 | unsigned long dst_i; | |
3659 | unsigned long src_i; | |
3660 | ||
3661 | if (src_offset + len > dst->len) { | |
d397712b CM |
3662 | printk(KERN_ERR "btrfs memmove bogus src_offset %lu move " |
3663 | "len %lu dst len %lu\n", src_offset, len, dst->len); | |
d1310b2e CM |
3664 | BUG_ON(1); |
3665 | } | |
3666 | if (dst_offset + len > dst->len) { | |
d397712b CM |
3667 | printk(KERN_ERR "btrfs memmove bogus dst_offset %lu move " |
3668 | "len %lu dst len %lu\n", dst_offset, len, dst->len); | |
d1310b2e CM |
3669 | BUG_ON(1); |
3670 | } | |
3671 | ||
d397712b | 3672 | while (len > 0) { |
d1310b2e CM |
3673 | dst_off_in_page = (start_offset + dst_offset) & |
3674 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3675 | src_off_in_page = (start_offset + src_offset) & | |
3676 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3677 | ||
3678 | dst_i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT; | |
3679 | src_i = (start_offset + src_offset) >> PAGE_CACHE_SHIFT; | |
3680 | ||
3681 | cur = min(len, (unsigned long)(PAGE_CACHE_SIZE - | |
3682 | src_off_in_page)); | |
3683 | cur = min_t(unsigned long, cur, | |
3684 | (unsigned long)(PAGE_CACHE_SIZE - dst_off_in_page)); | |
3685 | ||
3686 | copy_pages(extent_buffer_page(dst, dst_i), | |
3687 | extent_buffer_page(dst, src_i), | |
3688 | dst_off_in_page, src_off_in_page, cur); | |
3689 | ||
3690 | src_offset += cur; | |
3691 | dst_offset += cur; | |
3692 | len -= cur; | |
3693 | } | |
3694 | } | |
3695 | EXPORT_SYMBOL(memcpy_extent_buffer); | |
3696 | ||
3697 | void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, | |
3698 | unsigned long src_offset, unsigned long len) | |
3699 | { | |
3700 | size_t cur; | |
3701 | size_t dst_off_in_page; | |
3702 | size_t src_off_in_page; | |
3703 | unsigned long dst_end = dst_offset + len - 1; | |
3704 | unsigned long src_end = src_offset + len - 1; | |
3705 | size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3706 | unsigned long dst_i; | |
3707 | unsigned long src_i; | |
3708 | ||
3709 | if (src_offset + len > dst->len) { | |
d397712b CM |
3710 | printk(KERN_ERR "btrfs memmove bogus src_offset %lu move " |
3711 | "len %lu len %lu\n", src_offset, len, dst->len); | |
d1310b2e CM |
3712 | BUG_ON(1); |
3713 | } | |
3714 | if (dst_offset + len > dst->len) { | |
d397712b CM |
3715 | printk(KERN_ERR "btrfs memmove bogus dst_offset %lu move " |
3716 | "len %lu len %lu\n", dst_offset, len, dst->len); | |
d1310b2e CM |
3717 | BUG_ON(1); |
3718 | } | |
3719 | if (dst_offset < src_offset) { | |
3720 | memcpy_extent_buffer(dst, dst_offset, src_offset, len); | |
3721 | return; | |
3722 | } | |
d397712b | 3723 | while (len > 0) { |
d1310b2e CM |
3724 | dst_i = (start_offset + dst_end) >> PAGE_CACHE_SHIFT; |
3725 | src_i = (start_offset + src_end) >> PAGE_CACHE_SHIFT; | |
3726 | ||
3727 | dst_off_in_page = (start_offset + dst_end) & | |
3728 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3729 | src_off_in_page = (start_offset + src_end) & | |
3730 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3731 | ||
3732 | cur = min_t(unsigned long, len, src_off_in_page + 1); | |
3733 | cur = min(cur, dst_off_in_page + 1); | |
3734 | move_pages(extent_buffer_page(dst, dst_i), | |
3735 | extent_buffer_page(dst, src_i), | |
3736 | dst_off_in_page - cur + 1, | |
3737 | src_off_in_page - cur + 1, cur); | |
3738 | ||
3739 | dst_end -= cur; | |
3740 | src_end -= cur; | |
3741 | len -= cur; | |
3742 | } | |
3743 | } | |
3744 | EXPORT_SYMBOL(memmove_extent_buffer); | |
6af118ce CM |
3745 | |
3746 | int try_release_extent_buffer(struct extent_io_tree *tree, struct page *page) | |
3747 | { | |
3748 | u64 start = page_offset(page); | |
3749 | struct extent_buffer *eb; | |
3750 | int ret = 1; | |
3751 | unsigned long i; | |
3752 | unsigned long num_pages; | |
3753 | ||
3754 | spin_lock(&tree->buffer_lock); | |
3755 | eb = buffer_search(tree, start); | |
3756 | if (!eb) | |
3757 | goto out; | |
3758 | ||
3759 | if (atomic_read(&eb->refs) > 1) { | |
3760 | ret = 0; | |
3761 | goto out; | |
3762 | } | |
3763 | /* at this point we can safely release the extent buffer */ | |
3764 | num_pages = num_extent_pages(eb->start, eb->len); | |
b214107e CH |
3765 | for (i = 0; i < num_pages; i++) |
3766 | page_cache_release(extent_buffer_page(eb, i)); | |
6af118ce CM |
3767 | rb_erase(&eb->rb_node, &tree->buffer); |
3768 | __free_extent_buffer(eb); | |
3769 | out: | |
3770 | spin_unlock(&tree->buffer_lock); | |
3771 | return ret; | |
3772 | } | |
3773 | EXPORT_SYMBOL(try_release_extent_buffer); |