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> | |
d1310b2e CM |
12 | #include <linux/writeback.h> |
13 | #include <linux/pagevec.h> | |
14 | #include "extent_io.h" | |
15 | #include "extent_map.h" | |
2db04966 | 16 | #include "compat.h" |
902b22f3 DW |
17 | #include "ctree.h" |
18 | #include "btrfs_inode.h" | |
d1310b2e CM |
19 | |
20 | /* temporary define until extent_map moves out of btrfs */ | |
21 | struct kmem_cache *btrfs_cache_create(const char *name, size_t size, | |
22 | unsigned long extra_flags, | |
23 | void (*ctor)(void *, struct kmem_cache *, | |
24 | unsigned long)); | |
25 | ||
26 | static struct kmem_cache *extent_state_cache; | |
27 | static struct kmem_cache *extent_buffer_cache; | |
28 | ||
29 | static LIST_HEAD(buffers); | |
30 | static LIST_HEAD(states); | |
4bef0848 | 31 | |
b47eda86 | 32 | #define LEAK_DEBUG 0 |
3935127c | 33 | #if LEAK_DEBUG |
d397712b | 34 | static DEFINE_SPINLOCK(leak_lock); |
4bef0848 | 35 | #endif |
d1310b2e | 36 | |
d1310b2e CM |
37 | #define BUFFER_LRU_MAX 64 |
38 | ||
39 | struct tree_entry { | |
40 | u64 start; | |
41 | u64 end; | |
d1310b2e CM |
42 | struct rb_node rb_node; |
43 | }; | |
44 | ||
45 | struct extent_page_data { | |
46 | struct bio *bio; | |
47 | struct extent_io_tree *tree; | |
48 | get_extent_t *get_extent; | |
771ed689 CM |
49 | |
50 | /* tells writepage not to lock the state bits for this range | |
51 | * it still does the unlocking | |
52 | */ | |
ffbd517d CM |
53 | unsigned int extent_locked:1; |
54 | ||
55 | /* tells the submit_bio code to use a WRITE_SYNC */ | |
56 | unsigned int sync_io:1; | |
d1310b2e CM |
57 | }; |
58 | ||
59 | int __init extent_io_init(void) | |
60 | { | |
61 | extent_state_cache = btrfs_cache_create("extent_state", | |
62 | sizeof(struct extent_state), 0, | |
63 | NULL); | |
64 | if (!extent_state_cache) | |
65 | return -ENOMEM; | |
66 | ||
67 | extent_buffer_cache = btrfs_cache_create("extent_buffers", | |
68 | sizeof(struct extent_buffer), 0, | |
69 | NULL); | |
70 | if (!extent_buffer_cache) | |
71 | goto free_state_cache; | |
72 | return 0; | |
73 | ||
74 | free_state_cache: | |
75 | kmem_cache_destroy(extent_state_cache); | |
76 | return -ENOMEM; | |
77 | } | |
78 | ||
79 | void extent_io_exit(void) | |
80 | { | |
81 | struct extent_state *state; | |
2d2ae547 | 82 | struct extent_buffer *eb; |
d1310b2e CM |
83 | |
84 | while (!list_empty(&states)) { | |
2d2ae547 | 85 | state = list_entry(states.next, struct extent_state, leak_list); |
d397712b CM |
86 | printk(KERN_ERR "btrfs state leak: start %llu end %llu " |
87 | "state %lu in tree %p refs %d\n", | |
88 | (unsigned long long)state->start, | |
89 | (unsigned long long)state->end, | |
90 | state->state, state->tree, atomic_read(&state->refs)); | |
2d2ae547 | 91 | list_del(&state->leak_list); |
d1310b2e CM |
92 | kmem_cache_free(extent_state_cache, state); |
93 | ||
94 | } | |
95 | ||
2d2ae547 CM |
96 | while (!list_empty(&buffers)) { |
97 | eb = list_entry(buffers.next, struct extent_buffer, leak_list); | |
d397712b CM |
98 | printk(KERN_ERR "btrfs buffer leak start %llu len %lu " |
99 | "refs %d\n", (unsigned long long)eb->start, | |
100 | eb->len, atomic_read(&eb->refs)); | |
2d2ae547 CM |
101 | list_del(&eb->leak_list); |
102 | kmem_cache_free(extent_buffer_cache, eb); | |
103 | } | |
d1310b2e CM |
104 | if (extent_state_cache) |
105 | kmem_cache_destroy(extent_state_cache); | |
106 | if (extent_buffer_cache) | |
107 | kmem_cache_destroy(extent_buffer_cache); | |
108 | } | |
109 | ||
110 | void extent_io_tree_init(struct extent_io_tree *tree, | |
111 | struct address_space *mapping, gfp_t mask) | |
112 | { | |
113 | tree->state.rb_node = NULL; | |
6af118ce | 114 | tree->buffer.rb_node = NULL; |
d1310b2e CM |
115 | tree->ops = NULL; |
116 | tree->dirty_bytes = 0; | |
70dec807 | 117 | spin_lock_init(&tree->lock); |
6af118ce | 118 | spin_lock_init(&tree->buffer_lock); |
d1310b2e | 119 | tree->mapping = mapping; |
d1310b2e | 120 | } |
d1310b2e | 121 | |
b2950863 | 122 | static struct extent_state *alloc_extent_state(gfp_t mask) |
d1310b2e CM |
123 | { |
124 | struct extent_state *state; | |
3935127c | 125 | #if LEAK_DEBUG |
2d2ae547 | 126 | unsigned long flags; |
4bef0848 | 127 | #endif |
d1310b2e CM |
128 | |
129 | state = kmem_cache_alloc(extent_state_cache, mask); | |
2b114d1d | 130 | if (!state) |
d1310b2e CM |
131 | return state; |
132 | state->state = 0; | |
d1310b2e | 133 | state->private = 0; |
70dec807 | 134 | state->tree = NULL; |
3935127c | 135 | #if LEAK_DEBUG |
2d2ae547 CM |
136 | spin_lock_irqsave(&leak_lock, flags); |
137 | list_add(&state->leak_list, &states); | |
138 | spin_unlock_irqrestore(&leak_lock, flags); | |
4bef0848 | 139 | #endif |
d1310b2e CM |
140 | atomic_set(&state->refs, 1); |
141 | init_waitqueue_head(&state->wq); | |
142 | return state; | |
143 | } | |
d1310b2e | 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)) { | |
3935127c | 150 | #if LEAK_DEBUG |
2d2ae547 | 151 | unsigned long flags; |
4bef0848 | 152 | #endif |
70dec807 | 153 | WARN_ON(state->tree); |
3935127c | 154 | #if 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 | } | |
d1310b2e CM |
162 | |
163 | static struct rb_node *tree_insert(struct rb_root *root, u64 offset, | |
164 | struct rb_node *node) | |
165 | { | |
d397712b CM |
166 | struct rb_node **p = &root->rb_node; |
167 | struct rb_node *parent = NULL; | |
d1310b2e CM |
168 | struct tree_entry *entry; |
169 | ||
d397712b | 170 | while (*p) { |
d1310b2e CM |
171 | parent = *p; |
172 | entry = rb_entry(parent, struct tree_entry, rb_node); | |
173 | ||
174 | if (offset < entry->start) | |
175 | p = &(*p)->rb_left; | |
176 | else if (offset > entry->end) | |
177 | p = &(*p)->rb_right; | |
178 | else | |
179 | return parent; | |
180 | } | |
181 | ||
182 | entry = rb_entry(node, struct tree_entry, rb_node); | |
d1310b2e CM |
183 | rb_link_node(node, parent, p); |
184 | rb_insert_color(node, root); | |
185 | return NULL; | |
186 | } | |
187 | ||
80ea96b1 | 188 | static struct rb_node *__etree_search(struct extent_io_tree *tree, u64 offset, |
d1310b2e CM |
189 | struct rb_node **prev_ret, |
190 | struct rb_node **next_ret) | |
191 | { | |
80ea96b1 | 192 | struct rb_root *root = &tree->state; |
d397712b | 193 | struct rb_node *n = root->rb_node; |
d1310b2e CM |
194 | struct rb_node *prev = NULL; |
195 | struct rb_node *orig_prev = NULL; | |
196 | struct tree_entry *entry; | |
197 | struct tree_entry *prev_entry = NULL; | |
198 | ||
d397712b | 199 | while (n) { |
d1310b2e CM |
200 | entry = rb_entry(n, struct tree_entry, rb_node); |
201 | prev = n; | |
202 | prev_entry = entry; | |
203 | ||
204 | if (offset < entry->start) | |
205 | n = n->rb_left; | |
206 | else if (offset > entry->end) | |
207 | n = n->rb_right; | |
d397712b | 208 | else |
d1310b2e CM |
209 | return n; |
210 | } | |
211 | ||
212 | if (prev_ret) { | |
213 | orig_prev = prev; | |
d397712b | 214 | while (prev && offset > prev_entry->end) { |
d1310b2e CM |
215 | prev = rb_next(prev); |
216 | prev_entry = rb_entry(prev, struct tree_entry, rb_node); | |
217 | } | |
218 | *prev_ret = prev; | |
219 | prev = orig_prev; | |
220 | } | |
221 | ||
222 | if (next_ret) { | |
223 | prev_entry = rb_entry(prev, struct tree_entry, rb_node); | |
d397712b | 224 | while (prev && offset < prev_entry->start) { |
d1310b2e CM |
225 | prev = rb_prev(prev); |
226 | prev_entry = rb_entry(prev, struct tree_entry, rb_node); | |
227 | } | |
228 | *next_ret = prev; | |
229 | } | |
230 | return NULL; | |
231 | } | |
232 | ||
80ea96b1 CM |
233 | static inline struct rb_node *tree_search(struct extent_io_tree *tree, |
234 | u64 offset) | |
d1310b2e | 235 | { |
70dec807 | 236 | struct rb_node *prev = NULL; |
d1310b2e | 237 | struct rb_node *ret; |
70dec807 | 238 | |
80ea96b1 | 239 | ret = __etree_search(tree, offset, &prev, NULL); |
d397712b | 240 | if (!ret) |
d1310b2e CM |
241 | return prev; |
242 | return ret; | |
243 | } | |
244 | ||
6af118ce CM |
245 | static struct extent_buffer *buffer_tree_insert(struct extent_io_tree *tree, |
246 | u64 offset, struct rb_node *node) | |
247 | { | |
248 | struct rb_root *root = &tree->buffer; | |
d397712b CM |
249 | struct rb_node **p = &root->rb_node; |
250 | struct rb_node *parent = NULL; | |
6af118ce CM |
251 | struct extent_buffer *eb; |
252 | ||
d397712b | 253 | while (*p) { |
6af118ce CM |
254 | parent = *p; |
255 | eb = rb_entry(parent, struct extent_buffer, rb_node); | |
256 | ||
257 | if (offset < eb->start) | |
258 | p = &(*p)->rb_left; | |
259 | else if (offset > eb->start) | |
260 | p = &(*p)->rb_right; | |
261 | else | |
262 | return eb; | |
263 | } | |
264 | ||
265 | rb_link_node(node, parent, p); | |
266 | rb_insert_color(node, root); | |
267 | return NULL; | |
268 | } | |
269 | ||
270 | static struct extent_buffer *buffer_search(struct extent_io_tree *tree, | |
271 | u64 offset) | |
272 | { | |
273 | struct rb_root *root = &tree->buffer; | |
d397712b | 274 | struct rb_node *n = root->rb_node; |
6af118ce CM |
275 | struct extent_buffer *eb; |
276 | ||
d397712b | 277 | while (n) { |
6af118ce CM |
278 | eb = rb_entry(n, struct extent_buffer, rb_node); |
279 | if (offset < eb->start) | |
280 | n = n->rb_left; | |
281 | else if (offset > eb->start) | |
282 | n = n->rb_right; | |
283 | else | |
284 | return eb; | |
285 | } | |
286 | return NULL; | |
287 | } | |
288 | ||
d1310b2e CM |
289 | /* |
290 | * utility function to look for merge candidates inside a given range. | |
291 | * Any extents with matching state are merged together into a single | |
292 | * extent in the tree. Extents with EXTENT_IO in their state field | |
293 | * are not merged because the end_io handlers need to be able to do | |
294 | * operations on them without sleeping (or doing allocations/splits). | |
295 | * | |
296 | * This should be called with the tree lock held. | |
297 | */ | |
298 | static int merge_state(struct extent_io_tree *tree, | |
299 | struct extent_state *state) | |
300 | { | |
301 | struct extent_state *other; | |
302 | struct rb_node *other_node; | |
303 | ||
5b21f2ed | 304 | if (state->state & (EXTENT_IOBITS | EXTENT_BOUNDARY)) |
d1310b2e CM |
305 | return 0; |
306 | ||
307 | other_node = rb_prev(&state->rb_node); | |
308 | if (other_node) { | |
309 | other = rb_entry(other_node, struct extent_state, rb_node); | |
310 | if (other->end == state->start - 1 && | |
311 | other->state == state->state) { | |
312 | state->start = other->start; | |
70dec807 | 313 | other->tree = NULL; |
d1310b2e CM |
314 | rb_erase(&other->rb_node, &tree->state); |
315 | free_extent_state(other); | |
316 | } | |
317 | } | |
318 | other_node = rb_next(&state->rb_node); | |
319 | if (other_node) { | |
320 | other = rb_entry(other_node, struct extent_state, rb_node); | |
321 | if (other->start == state->end + 1 && | |
322 | other->state == state->state) { | |
323 | other->start = state->start; | |
70dec807 | 324 | state->tree = NULL; |
d1310b2e CM |
325 | rb_erase(&state->rb_node, &tree->state); |
326 | free_extent_state(state); | |
327 | } | |
328 | } | |
329 | return 0; | |
330 | } | |
331 | ||
291d673e CM |
332 | static void set_state_cb(struct extent_io_tree *tree, |
333 | struct extent_state *state, | |
334 | unsigned long bits) | |
335 | { | |
336 | if (tree->ops && tree->ops->set_bit_hook) { | |
337 | tree->ops->set_bit_hook(tree->mapping->host, state->start, | |
b0c68f8b | 338 | state->end, state->state, bits); |
291d673e CM |
339 | } |
340 | } | |
341 | ||
342 | static void clear_state_cb(struct extent_io_tree *tree, | |
343 | struct extent_state *state, | |
344 | unsigned long bits) | |
345 | { | |
c584482b | 346 | if (tree->ops && tree->ops->clear_bit_hook) { |
291d673e | 347 | tree->ops->clear_bit_hook(tree->mapping->host, state->start, |
b0c68f8b | 348 | state->end, state->state, bits); |
291d673e CM |
349 | } |
350 | } | |
351 | ||
d1310b2e CM |
352 | /* |
353 | * insert an extent_state struct into the tree. 'bits' are set on the | |
354 | * struct before it is inserted. | |
355 | * | |
356 | * This may return -EEXIST if the extent is already there, in which case the | |
357 | * state struct is freed. | |
358 | * | |
359 | * The tree lock is not taken internally. This is a utility function and | |
360 | * probably isn't what you want to call (see set/clear_extent_bit). | |
361 | */ | |
362 | static int insert_state(struct extent_io_tree *tree, | |
363 | struct extent_state *state, u64 start, u64 end, | |
364 | int bits) | |
365 | { | |
366 | struct rb_node *node; | |
367 | ||
368 | if (end < start) { | |
d397712b CM |
369 | printk(KERN_ERR "btrfs end < start %llu %llu\n", |
370 | (unsigned long long)end, | |
371 | (unsigned long long)start); | |
d1310b2e CM |
372 | WARN_ON(1); |
373 | } | |
374 | if (bits & EXTENT_DIRTY) | |
375 | tree->dirty_bytes += end - start + 1; | |
b0c68f8b | 376 | set_state_cb(tree, state, bits); |
d1310b2e CM |
377 | state->state |= bits; |
378 | state->start = start; | |
379 | state->end = end; | |
380 | node = tree_insert(&tree->state, end, &state->rb_node); | |
381 | if (node) { | |
382 | struct extent_state *found; | |
383 | found = rb_entry(node, struct extent_state, rb_node); | |
d397712b CM |
384 | printk(KERN_ERR "btrfs found node %llu %llu on insert of " |
385 | "%llu %llu\n", (unsigned long long)found->start, | |
386 | (unsigned long long)found->end, | |
387 | (unsigned long long)start, (unsigned long long)end); | |
d1310b2e CM |
388 | free_extent_state(state); |
389 | return -EEXIST; | |
390 | } | |
70dec807 | 391 | state->tree = tree; |
d1310b2e CM |
392 | merge_state(tree, state); |
393 | return 0; | |
394 | } | |
395 | ||
396 | /* | |
397 | * split a given extent state struct in two, inserting the preallocated | |
398 | * struct 'prealloc' as the newly created second half. 'split' indicates an | |
399 | * offset inside 'orig' where it should be split. | |
400 | * | |
401 | * Before calling, | |
402 | * the tree has 'orig' at [orig->start, orig->end]. After calling, there | |
403 | * are two extent state structs in the tree: | |
404 | * prealloc: [orig->start, split - 1] | |
405 | * orig: [ split, orig->end ] | |
406 | * | |
407 | * The tree locks are not taken by this function. They need to be held | |
408 | * by the caller. | |
409 | */ | |
410 | static int split_state(struct extent_io_tree *tree, struct extent_state *orig, | |
411 | struct extent_state *prealloc, u64 split) | |
412 | { | |
413 | struct rb_node *node; | |
414 | prealloc->start = orig->start; | |
415 | prealloc->end = split - 1; | |
416 | prealloc->state = orig->state; | |
417 | orig->start = split; | |
418 | ||
419 | node = tree_insert(&tree->state, prealloc->end, &prealloc->rb_node); | |
420 | if (node) { | |
d1310b2e CM |
421 | free_extent_state(prealloc); |
422 | return -EEXIST; | |
423 | } | |
70dec807 | 424 | prealloc->tree = tree; |
d1310b2e CM |
425 | return 0; |
426 | } | |
427 | ||
428 | /* | |
429 | * utility function to clear some bits in an extent state struct. | |
430 | * it will optionally wake up any one waiting on this state (wake == 1), or | |
431 | * forcibly remove the state from the tree (delete == 1). | |
432 | * | |
433 | * If no bits are set on the state struct after clearing things, the | |
434 | * struct is freed and removed from the tree | |
435 | */ | |
436 | static int clear_state_bit(struct extent_io_tree *tree, | |
437 | struct extent_state *state, int bits, int wake, | |
438 | int delete) | |
439 | { | |
440 | int ret = state->state & bits; | |
441 | ||
442 | if ((bits & EXTENT_DIRTY) && (state->state & EXTENT_DIRTY)) { | |
443 | u64 range = state->end - state->start + 1; | |
444 | WARN_ON(range > tree->dirty_bytes); | |
445 | tree->dirty_bytes -= range; | |
446 | } | |
291d673e | 447 | clear_state_cb(tree, state, bits); |
b0c68f8b | 448 | state->state &= ~bits; |
d1310b2e CM |
449 | if (wake) |
450 | wake_up(&state->wq); | |
451 | if (delete || state->state == 0) { | |
70dec807 | 452 | if (state->tree) { |
ae9d1285 | 453 | clear_state_cb(tree, state, state->state); |
d1310b2e | 454 | rb_erase(&state->rb_node, &tree->state); |
70dec807 | 455 | state->tree = NULL; |
d1310b2e CM |
456 | free_extent_state(state); |
457 | } else { | |
458 | WARN_ON(1); | |
459 | } | |
460 | } else { | |
461 | merge_state(tree, state); | |
462 | } | |
463 | return ret; | |
464 | } | |
465 | ||
466 | /* | |
467 | * clear some bits on a range in the tree. This may require splitting | |
468 | * or inserting elements in the tree, so the gfp mask is used to | |
469 | * indicate which allocations or sleeping are allowed. | |
470 | * | |
471 | * pass 'wake' == 1 to kick any sleepers, and 'delete' == 1 to remove | |
472 | * the given range from the tree regardless of state (ie for truncate). | |
473 | * | |
474 | * the range [start, end] is inclusive. | |
475 | * | |
476 | * This takes the tree lock, and returns < 0 on error, > 0 if any of the | |
477 | * bits were already set, or zero if none of the bits were already set. | |
478 | */ | |
479 | int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, | |
480 | int bits, int wake, int delete, gfp_t mask) | |
481 | { | |
482 | struct extent_state *state; | |
483 | struct extent_state *prealloc = NULL; | |
484 | struct rb_node *node; | |
d1310b2e CM |
485 | int err; |
486 | int set = 0; | |
487 | ||
488 | again: | |
489 | if (!prealloc && (mask & __GFP_WAIT)) { | |
490 | prealloc = alloc_extent_state(mask); | |
491 | if (!prealloc) | |
492 | return -ENOMEM; | |
493 | } | |
494 | ||
cad321ad | 495 | spin_lock(&tree->lock); |
d1310b2e CM |
496 | /* |
497 | * this search will find the extents that end after | |
498 | * our range starts | |
499 | */ | |
80ea96b1 | 500 | node = tree_search(tree, start); |
d1310b2e CM |
501 | if (!node) |
502 | goto out; | |
503 | state = rb_entry(node, struct extent_state, rb_node); | |
504 | if (state->start > end) | |
505 | goto out; | |
506 | WARN_ON(state->end < start); | |
507 | ||
508 | /* | |
509 | * | ---- desired range ---- | | |
510 | * | state | or | |
511 | * | ------------- state -------------- | | |
512 | * | |
513 | * We need to split the extent we found, and may flip | |
514 | * bits on second half. | |
515 | * | |
516 | * If the extent we found extends past our range, we | |
517 | * just split and search again. It'll get split again | |
518 | * the next time though. | |
519 | * | |
520 | * If the extent we found is inside our range, we clear | |
521 | * the desired bit on it. | |
522 | */ | |
523 | ||
524 | if (state->start < start) { | |
70dec807 CM |
525 | if (!prealloc) |
526 | prealloc = alloc_extent_state(GFP_ATOMIC); | |
d1310b2e CM |
527 | err = split_state(tree, state, prealloc, start); |
528 | BUG_ON(err == -EEXIST); | |
529 | prealloc = NULL; | |
530 | if (err) | |
531 | goto out; | |
532 | if (state->end <= end) { | |
533 | start = state->end + 1; | |
534 | set |= clear_state_bit(tree, state, bits, | |
535 | wake, delete); | |
536 | } else { | |
537 | start = state->start; | |
538 | } | |
539 | goto search_again; | |
540 | } | |
541 | /* | |
542 | * | ---- desired range ---- | | |
543 | * | state | | |
544 | * We need to split the extent, and clear the bit | |
545 | * on the first half | |
546 | */ | |
547 | if (state->start <= end && state->end > end) { | |
70dec807 CM |
548 | if (!prealloc) |
549 | prealloc = alloc_extent_state(GFP_ATOMIC); | |
d1310b2e CM |
550 | err = split_state(tree, state, prealloc, end + 1); |
551 | BUG_ON(err == -EEXIST); | |
552 | ||
553 | if (wake) | |
554 | wake_up(&state->wq); | |
555 | set |= clear_state_bit(tree, prealloc, bits, | |
556 | wake, delete); | |
557 | prealloc = NULL; | |
558 | goto out; | |
559 | } | |
560 | ||
561 | start = state->end + 1; | |
562 | set |= clear_state_bit(tree, state, bits, wake, delete); | |
563 | goto search_again; | |
564 | ||
565 | out: | |
cad321ad | 566 | spin_unlock(&tree->lock); |
d1310b2e CM |
567 | if (prealloc) |
568 | free_extent_state(prealloc); | |
569 | ||
570 | return set; | |
571 | ||
572 | search_again: | |
573 | if (start > end) | |
574 | goto out; | |
cad321ad | 575 | spin_unlock(&tree->lock); |
d1310b2e CM |
576 | if (mask & __GFP_WAIT) |
577 | cond_resched(); | |
578 | goto again; | |
579 | } | |
d1310b2e CM |
580 | |
581 | static int wait_on_state(struct extent_io_tree *tree, | |
582 | struct extent_state *state) | |
641f5219 CH |
583 | __releases(tree->lock) |
584 | __acquires(tree->lock) | |
d1310b2e CM |
585 | { |
586 | DEFINE_WAIT(wait); | |
587 | prepare_to_wait(&state->wq, &wait, TASK_UNINTERRUPTIBLE); | |
cad321ad | 588 | spin_unlock(&tree->lock); |
d1310b2e | 589 | schedule(); |
cad321ad | 590 | spin_lock(&tree->lock); |
d1310b2e CM |
591 | finish_wait(&state->wq, &wait); |
592 | return 0; | |
593 | } | |
594 | ||
595 | /* | |
596 | * waits for one or more bits to clear on a range in the state tree. | |
597 | * The range [start, end] is inclusive. | |
598 | * The tree lock is taken by this function | |
599 | */ | |
600 | int wait_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, int bits) | |
601 | { | |
602 | struct extent_state *state; | |
603 | struct rb_node *node; | |
604 | ||
cad321ad | 605 | spin_lock(&tree->lock); |
d1310b2e CM |
606 | again: |
607 | while (1) { | |
608 | /* | |
609 | * this search will find all the extents that end after | |
610 | * our range starts | |
611 | */ | |
80ea96b1 | 612 | node = tree_search(tree, start); |
d1310b2e CM |
613 | if (!node) |
614 | break; | |
615 | ||
616 | state = rb_entry(node, struct extent_state, rb_node); | |
617 | ||
618 | if (state->start > end) | |
619 | goto out; | |
620 | ||
621 | if (state->state & bits) { | |
622 | start = state->start; | |
623 | atomic_inc(&state->refs); | |
624 | wait_on_state(tree, state); | |
625 | free_extent_state(state); | |
626 | goto again; | |
627 | } | |
628 | start = state->end + 1; | |
629 | ||
630 | if (start > end) | |
631 | break; | |
632 | ||
633 | if (need_resched()) { | |
cad321ad | 634 | spin_unlock(&tree->lock); |
d1310b2e | 635 | cond_resched(); |
cad321ad | 636 | spin_lock(&tree->lock); |
d1310b2e CM |
637 | } |
638 | } | |
639 | out: | |
cad321ad | 640 | spin_unlock(&tree->lock); |
d1310b2e CM |
641 | return 0; |
642 | } | |
d1310b2e CM |
643 | |
644 | static void set_state_bits(struct extent_io_tree *tree, | |
645 | struct extent_state *state, | |
646 | int bits) | |
647 | { | |
648 | if ((bits & EXTENT_DIRTY) && !(state->state & EXTENT_DIRTY)) { | |
649 | u64 range = state->end - state->start + 1; | |
650 | tree->dirty_bytes += range; | |
651 | } | |
291d673e | 652 | set_state_cb(tree, state, bits); |
b0c68f8b | 653 | state->state |= bits; |
d1310b2e CM |
654 | } |
655 | ||
656 | /* | |
657 | * set some bits on a range in the tree. This may require allocations | |
658 | * or sleeping, so the gfp mask is used to indicate what is allowed. | |
659 | * | |
660 | * If 'exclusive' == 1, this will fail with -EEXIST if some part of the | |
661 | * range already has the desired bits set. The start of the existing | |
662 | * range is returned in failed_start in this case. | |
663 | * | |
664 | * [start, end] is inclusive | |
665 | * This takes the tree lock. | |
666 | */ | |
d397712b CM |
667 | static int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, |
668 | int bits, int exclusive, u64 *failed_start, | |
669 | gfp_t mask) | |
d1310b2e CM |
670 | { |
671 | struct extent_state *state; | |
672 | struct extent_state *prealloc = NULL; | |
673 | struct rb_node *node; | |
d1310b2e CM |
674 | int err = 0; |
675 | int set; | |
676 | u64 last_start; | |
677 | u64 last_end; | |
678 | again: | |
679 | if (!prealloc && (mask & __GFP_WAIT)) { | |
680 | prealloc = alloc_extent_state(mask); | |
681 | if (!prealloc) | |
682 | return -ENOMEM; | |
683 | } | |
684 | ||
cad321ad | 685 | spin_lock(&tree->lock); |
d1310b2e CM |
686 | /* |
687 | * this search will find all the extents that end after | |
688 | * our range starts. | |
689 | */ | |
80ea96b1 | 690 | node = tree_search(tree, start); |
d1310b2e CM |
691 | if (!node) { |
692 | err = insert_state(tree, prealloc, start, end, bits); | |
693 | prealloc = NULL; | |
694 | BUG_ON(err == -EEXIST); | |
695 | goto out; | |
696 | } | |
697 | ||
698 | state = rb_entry(node, struct extent_state, rb_node); | |
699 | last_start = state->start; | |
700 | last_end = state->end; | |
701 | ||
702 | /* | |
703 | * | ---- desired range ---- | | |
704 | * | state | | |
705 | * | |
706 | * Just lock what we found and keep going | |
707 | */ | |
708 | if (state->start == start && state->end <= end) { | |
709 | set = state->state & bits; | |
710 | if (set && exclusive) { | |
711 | *failed_start = state->start; | |
712 | err = -EEXIST; | |
713 | goto out; | |
714 | } | |
715 | set_state_bits(tree, state, bits); | |
716 | start = state->end + 1; | |
717 | merge_state(tree, state); | |
718 | goto search_again; | |
719 | } | |
720 | ||
721 | /* | |
722 | * | ---- desired range ---- | | |
723 | * | state | | |
724 | * or | |
725 | * | ------------- state -------------- | | |
726 | * | |
727 | * We need to split the extent we found, and may flip bits on | |
728 | * second half. | |
729 | * | |
730 | * If the extent we found extends past our | |
731 | * range, we just split and search again. It'll get split | |
732 | * again the next time though. | |
733 | * | |
734 | * If the extent we found is inside our range, we set the | |
735 | * desired bit on it. | |
736 | */ | |
737 | if (state->start < start) { | |
738 | set = state->state & bits; | |
739 | if (exclusive && set) { | |
740 | *failed_start = start; | |
741 | err = -EEXIST; | |
742 | goto out; | |
743 | } | |
744 | err = split_state(tree, state, prealloc, start); | |
745 | BUG_ON(err == -EEXIST); | |
746 | prealloc = NULL; | |
747 | if (err) | |
748 | goto out; | |
749 | if (state->end <= end) { | |
750 | set_state_bits(tree, state, bits); | |
751 | start = state->end + 1; | |
752 | merge_state(tree, state); | |
753 | } else { | |
754 | start = state->start; | |
755 | } | |
756 | goto search_again; | |
757 | } | |
758 | /* | |
759 | * | ---- desired range ---- | | |
760 | * | state | or | state | | |
761 | * | |
762 | * There's a hole, we need to insert something in it and | |
763 | * ignore the extent we found. | |
764 | */ | |
765 | if (state->start > start) { | |
766 | u64 this_end; | |
767 | if (end < last_start) | |
768 | this_end = end; | |
769 | else | |
d397712b | 770 | this_end = last_start - 1; |
d1310b2e CM |
771 | err = insert_state(tree, prealloc, start, this_end, |
772 | bits); | |
773 | prealloc = NULL; | |
774 | BUG_ON(err == -EEXIST); | |
775 | if (err) | |
776 | goto out; | |
777 | start = this_end + 1; | |
778 | goto search_again; | |
779 | } | |
780 | /* | |
781 | * | ---- desired range ---- | | |
782 | * | state | | |
783 | * We need to split the extent, and set the bit | |
784 | * on the first half | |
785 | */ | |
786 | if (state->start <= end && state->end > end) { | |
787 | set = state->state & bits; | |
788 | if (exclusive && set) { | |
789 | *failed_start = start; | |
790 | err = -EEXIST; | |
791 | goto out; | |
792 | } | |
793 | err = split_state(tree, state, prealloc, end + 1); | |
794 | BUG_ON(err == -EEXIST); | |
795 | ||
796 | set_state_bits(tree, prealloc, bits); | |
797 | merge_state(tree, prealloc); | |
798 | prealloc = NULL; | |
799 | goto out; | |
800 | } | |
801 | ||
802 | goto search_again; | |
803 | ||
804 | out: | |
cad321ad | 805 | spin_unlock(&tree->lock); |
d1310b2e CM |
806 | if (prealloc) |
807 | free_extent_state(prealloc); | |
808 | ||
809 | return err; | |
810 | ||
811 | search_again: | |
812 | if (start > end) | |
813 | goto out; | |
cad321ad | 814 | spin_unlock(&tree->lock); |
d1310b2e CM |
815 | if (mask & __GFP_WAIT) |
816 | cond_resched(); | |
817 | goto again; | |
818 | } | |
d1310b2e CM |
819 | |
820 | /* wrappers around set/clear extent bit */ | |
821 | int set_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end, | |
822 | gfp_t mask) | |
823 | { | |
824 | return set_extent_bit(tree, start, end, EXTENT_DIRTY, 0, NULL, | |
825 | mask); | |
826 | } | |
d1310b2e | 827 | |
e6dcd2dc CM |
828 | int set_extent_ordered(struct extent_io_tree *tree, u64 start, u64 end, |
829 | gfp_t mask) | |
830 | { | |
831 | return set_extent_bit(tree, start, end, EXTENT_ORDERED, 0, NULL, mask); | |
832 | } | |
e6dcd2dc | 833 | |
d1310b2e CM |
834 | int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, |
835 | int bits, gfp_t mask) | |
836 | { | |
837 | return set_extent_bit(tree, start, end, bits, 0, NULL, | |
838 | mask); | |
839 | } | |
d1310b2e CM |
840 | |
841 | int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, | |
842 | int bits, gfp_t mask) | |
843 | { | |
844 | return clear_extent_bit(tree, start, end, bits, 0, 0, mask); | |
845 | } | |
d1310b2e CM |
846 | |
847 | int set_extent_delalloc(struct extent_io_tree *tree, u64 start, u64 end, | |
848 | gfp_t mask) | |
849 | { | |
850 | return set_extent_bit(tree, start, end, | |
e6dcd2dc CM |
851 | EXTENT_DELALLOC | EXTENT_DIRTY, |
852 | 0, NULL, mask); | |
d1310b2e | 853 | } |
d1310b2e CM |
854 | |
855 | int clear_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end, | |
856 | gfp_t mask) | |
857 | { | |
858 | return clear_extent_bit(tree, start, end, | |
859 | EXTENT_DIRTY | EXTENT_DELALLOC, 0, 0, mask); | |
860 | } | |
d1310b2e | 861 | |
e6dcd2dc CM |
862 | int clear_extent_ordered(struct extent_io_tree *tree, u64 start, u64 end, |
863 | gfp_t mask) | |
864 | { | |
865 | return clear_extent_bit(tree, start, end, EXTENT_ORDERED, 1, 0, mask); | |
866 | } | |
e6dcd2dc | 867 | |
d1310b2e CM |
868 | int set_extent_new(struct extent_io_tree *tree, u64 start, u64 end, |
869 | gfp_t mask) | |
870 | { | |
871 | return set_extent_bit(tree, start, end, EXTENT_NEW, 0, NULL, | |
872 | mask); | |
873 | } | |
d1310b2e | 874 | |
b2950863 | 875 | static int clear_extent_new(struct extent_io_tree *tree, u64 start, u64 end, |
d1310b2e CM |
876 | gfp_t mask) |
877 | { | |
878 | return clear_extent_bit(tree, start, end, EXTENT_NEW, 0, 0, mask); | |
879 | } | |
d1310b2e CM |
880 | |
881 | int set_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end, | |
882 | gfp_t mask) | |
883 | { | |
884 | return set_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, NULL, | |
885 | mask); | |
886 | } | |
d1310b2e | 887 | |
d397712b CM |
888 | static int clear_extent_uptodate(struct extent_io_tree *tree, u64 start, |
889 | u64 end, gfp_t mask) | |
d1310b2e CM |
890 | { |
891 | return clear_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, 0, mask); | |
892 | } | |
d1310b2e | 893 | |
b2950863 | 894 | static int set_extent_writeback(struct extent_io_tree *tree, u64 start, u64 end, |
d1310b2e CM |
895 | gfp_t mask) |
896 | { | |
897 | return set_extent_bit(tree, start, end, EXTENT_WRITEBACK, | |
898 | 0, NULL, mask); | |
899 | } | |
d1310b2e | 900 | |
d397712b CM |
901 | static int clear_extent_writeback(struct extent_io_tree *tree, u64 start, |
902 | u64 end, gfp_t mask) | |
d1310b2e CM |
903 | { |
904 | return clear_extent_bit(tree, start, end, EXTENT_WRITEBACK, 1, 0, mask); | |
905 | } | |
d1310b2e CM |
906 | |
907 | int wait_on_extent_writeback(struct extent_io_tree *tree, u64 start, u64 end) | |
908 | { | |
909 | return wait_extent_bit(tree, start, end, EXTENT_WRITEBACK); | |
910 | } | |
d1310b2e | 911 | |
d352ac68 CM |
912 | /* |
913 | * either insert or lock state struct between start and end use mask to tell | |
914 | * us if waiting is desired. | |
915 | */ | |
d1310b2e CM |
916 | int lock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask) |
917 | { | |
918 | int err; | |
919 | u64 failed_start; | |
920 | while (1) { | |
921 | err = set_extent_bit(tree, start, end, EXTENT_LOCKED, 1, | |
922 | &failed_start, mask); | |
923 | if (err == -EEXIST && (mask & __GFP_WAIT)) { | |
924 | wait_extent_bit(tree, failed_start, end, EXTENT_LOCKED); | |
925 | start = failed_start; | |
926 | } else { | |
927 | break; | |
928 | } | |
929 | WARN_ON(start > end); | |
930 | } | |
931 | return err; | |
932 | } | |
d1310b2e | 933 | |
25179201 JB |
934 | int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end, |
935 | gfp_t mask) | |
936 | { | |
937 | int err; | |
938 | u64 failed_start; | |
939 | ||
940 | err = set_extent_bit(tree, start, end, EXTENT_LOCKED, 1, | |
941 | &failed_start, mask); | |
6643558d YZ |
942 | if (err == -EEXIST) { |
943 | if (failed_start > start) | |
944 | clear_extent_bit(tree, start, failed_start - 1, | |
945 | EXTENT_LOCKED, 1, 0, mask); | |
25179201 | 946 | return 0; |
6643558d | 947 | } |
25179201 JB |
948 | return 1; |
949 | } | |
25179201 | 950 | |
d1310b2e CM |
951 | int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end, |
952 | gfp_t mask) | |
953 | { | |
954 | return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, mask); | |
955 | } | |
d1310b2e CM |
956 | |
957 | /* | |
958 | * helper function to set pages and extents in the tree dirty | |
959 | */ | |
960 | int set_range_dirty(struct extent_io_tree *tree, u64 start, u64 end) | |
961 | { | |
962 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
963 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
964 | struct page *page; | |
965 | ||
966 | while (index <= end_index) { | |
967 | page = find_get_page(tree->mapping, index); | |
968 | BUG_ON(!page); | |
969 | __set_page_dirty_nobuffers(page); | |
970 | page_cache_release(page); | |
971 | index++; | |
972 | } | |
973 | set_extent_dirty(tree, start, end, GFP_NOFS); | |
974 | return 0; | |
975 | } | |
d1310b2e CM |
976 | |
977 | /* | |
978 | * helper function to set both pages and extents in the tree writeback | |
979 | */ | |
b2950863 | 980 | static int set_range_writeback(struct extent_io_tree *tree, u64 start, u64 end) |
d1310b2e CM |
981 | { |
982 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
983 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
984 | struct page *page; | |
985 | ||
986 | while (index <= end_index) { | |
987 | page = find_get_page(tree->mapping, index); | |
988 | BUG_ON(!page); | |
989 | set_page_writeback(page); | |
990 | page_cache_release(page); | |
991 | index++; | |
992 | } | |
993 | set_extent_writeback(tree, start, end, GFP_NOFS); | |
994 | return 0; | |
995 | } | |
d1310b2e | 996 | |
d352ac68 CM |
997 | /* |
998 | * find the first offset in the io tree with 'bits' set. zero is | |
999 | * returned if we find something, and *start_ret and *end_ret are | |
1000 | * set to reflect the state struct that was found. | |
1001 | * | |
1002 | * If nothing was found, 1 is returned, < 0 on error | |
1003 | */ | |
d1310b2e CM |
1004 | int find_first_extent_bit(struct extent_io_tree *tree, u64 start, |
1005 | u64 *start_ret, u64 *end_ret, int bits) | |
1006 | { | |
1007 | struct rb_node *node; | |
1008 | struct extent_state *state; | |
1009 | int ret = 1; | |
1010 | ||
cad321ad | 1011 | spin_lock(&tree->lock); |
d1310b2e CM |
1012 | /* |
1013 | * this search will find all the extents that end after | |
1014 | * our range starts. | |
1015 | */ | |
80ea96b1 | 1016 | node = tree_search(tree, start); |
d397712b | 1017 | if (!node) |
d1310b2e | 1018 | goto out; |
d1310b2e | 1019 | |
d397712b | 1020 | while (1) { |
d1310b2e CM |
1021 | state = rb_entry(node, struct extent_state, rb_node); |
1022 | if (state->end >= start && (state->state & bits)) { | |
1023 | *start_ret = state->start; | |
1024 | *end_ret = state->end; | |
1025 | ret = 0; | |
1026 | break; | |
1027 | } | |
1028 | node = rb_next(node); | |
1029 | if (!node) | |
1030 | break; | |
1031 | } | |
1032 | out: | |
cad321ad | 1033 | spin_unlock(&tree->lock); |
d1310b2e CM |
1034 | return ret; |
1035 | } | |
d1310b2e | 1036 | |
d352ac68 CM |
1037 | /* find the first state struct with 'bits' set after 'start', and |
1038 | * return it. tree->lock must be held. NULL will returned if | |
1039 | * nothing was found after 'start' | |
1040 | */ | |
d7fc640e CM |
1041 | struct extent_state *find_first_extent_bit_state(struct extent_io_tree *tree, |
1042 | u64 start, int bits) | |
1043 | { | |
1044 | struct rb_node *node; | |
1045 | struct extent_state *state; | |
1046 | ||
1047 | /* | |
1048 | * this search will find all the extents that end after | |
1049 | * our range starts. | |
1050 | */ | |
1051 | node = tree_search(tree, start); | |
d397712b | 1052 | if (!node) |
d7fc640e | 1053 | goto out; |
d7fc640e | 1054 | |
d397712b | 1055 | while (1) { |
d7fc640e | 1056 | state = rb_entry(node, struct extent_state, rb_node); |
d397712b | 1057 | if (state->end >= start && (state->state & bits)) |
d7fc640e | 1058 | return state; |
d397712b | 1059 | |
d7fc640e CM |
1060 | node = rb_next(node); |
1061 | if (!node) | |
1062 | break; | |
1063 | } | |
1064 | out: | |
1065 | return NULL; | |
1066 | } | |
d7fc640e | 1067 | |
d352ac68 CM |
1068 | /* |
1069 | * find a contiguous range of bytes in the file marked as delalloc, not | |
1070 | * more than 'max_bytes'. start and end are used to return the range, | |
1071 | * | |
1072 | * 1 is returned if we find something, 0 if nothing was in the tree | |
1073 | */ | |
c8b97818 CM |
1074 | static noinline u64 find_delalloc_range(struct extent_io_tree *tree, |
1075 | u64 *start, u64 *end, u64 max_bytes) | |
d1310b2e CM |
1076 | { |
1077 | struct rb_node *node; | |
1078 | struct extent_state *state; | |
1079 | u64 cur_start = *start; | |
1080 | u64 found = 0; | |
1081 | u64 total_bytes = 0; | |
1082 | ||
cad321ad | 1083 | spin_lock(&tree->lock); |
c8b97818 | 1084 | |
d1310b2e CM |
1085 | /* |
1086 | * this search will find all the extents that end after | |
1087 | * our range starts. | |
1088 | */ | |
80ea96b1 | 1089 | node = tree_search(tree, cur_start); |
2b114d1d | 1090 | if (!node) { |
3b951516 CM |
1091 | if (!found) |
1092 | *end = (u64)-1; | |
d1310b2e CM |
1093 | goto out; |
1094 | } | |
1095 | ||
d397712b | 1096 | while (1) { |
d1310b2e | 1097 | state = rb_entry(node, struct extent_state, rb_node); |
5b21f2ed ZY |
1098 | if (found && (state->start != cur_start || |
1099 | (state->state & EXTENT_BOUNDARY))) { | |
d1310b2e CM |
1100 | goto out; |
1101 | } | |
1102 | if (!(state->state & EXTENT_DELALLOC)) { | |
1103 | if (!found) | |
1104 | *end = state->end; | |
1105 | goto out; | |
1106 | } | |
d1310b2e CM |
1107 | if (!found) |
1108 | *start = state->start; | |
1109 | found++; | |
1110 | *end = state->end; | |
1111 | cur_start = state->end + 1; | |
1112 | node = rb_next(node); | |
1113 | if (!node) | |
1114 | break; | |
1115 | total_bytes += state->end - state->start + 1; | |
1116 | if (total_bytes >= max_bytes) | |
1117 | break; | |
1118 | } | |
1119 | out: | |
cad321ad | 1120 | spin_unlock(&tree->lock); |
d1310b2e CM |
1121 | return found; |
1122 | } | |
1123 | ||
c8b97818 CM |
1124 | static noinline int __unlock_for_delalloc(struct inode *inode, |
1125 | struct page *locked_page, | |
1126 | u64 start, u64 end) | |
1127 | { | |
1128 | int ret; | |
1129 | struct page *pages[16]; | |
1130 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1131 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
1132 | unsigned long nr_pages = end_index - index + 1; | |
1133 | int i; | |
1134 | ||
1135 | if (index == locked_page->index && end_index == index) | |
1136 | return 0; | |
1137 | ||
d397712b | 1138 | while (nr_pages > 0) { |
c8b97818 | 1139 | ret = find_get_pages_contig(inode->i_mapping, index, |
5b050f04 CM |
1140 | min_t(unsigned long, nr_pages, |
1141 | ARRAY_SIZE(pages)), pages); | |
c8b97818 CM |
1142 | for (i = 0; i < ret; i++) { |
1143 | if (pages[i] != locked_page) | |
1144 | unlock_page(pages[i]); | |
1145 | page_cache_release(pages[i]); | |
1146 | } | |
1147 | nr_pages -= ret; | |
1148 | index += ret; | |
1149 | cond_resched(); | |
1150 | } | |
1151 | return 0; | |
1152 | } | |
1153 | ||
1154 | static noinline int lock_delalloc_pages(struct inode *inode, | |
1155 | struct page *locked_page, | |
1156 | u64 delalloc_start, | |
1157 | u64 delalloc_end) | |
1158 | { | |
1159 | unsigned long index = delalloc_start >> PAGE_CACHE_SHIFT; | |
1160 | unsigned long start_index = index; | |
1161 | unsigned long end_index = delalloc_end >> PAGE_CACHE_SHIFT; | |
1162 | unsigned long pages_locked = 0; | |
1163 | struct page *pages[16]; | |
1164 | unsigned long nrpages; | |
1165 | int ret; | |
1166 | int i; | |
1167 | ||
1168 | /* the caller is responsible for locking the start index */ | |
1169 | if (index == locked_page->index && index == end_index) | |
1170 | return 0; | |
1171 | ||
1172 | /* skip the page at the start index */ | |
1173 | nrpages = end_index - index + 1; | |
d397712b | 1174 | while (nrpages > 0) { |
c8b97818 | 1175 | ret = find_get_pages_contig(inode->i_mapping, index, |
5b050f04 CM |
1176 | min_t(unsigned long, |
1177 | nrpages, ARRAY_SIZE(pages)), pages); | |
c8b97818 CM |
1178 | if (ret == 0) { |
1179 | ret = -EAGAIN; | |
1180 | goto done; | |
1181 | } | |
1182 | /* now we have an array of pages, lock them all */ | |
1183 | for (i = 0; i < ret; i++) { | |
1184 | /* | |
1185 | * the caller is taking responsibility for | |
1186 | * locked_page | |
1187 | */ | |
771ed689 | 1188 | if (pages[i] != locked_page) { |
c8b97818 | 1189 | lock_page(pages[i]); |
f2b1c41c CM |
1190 | if (!PageDirty(pages[i]) || |
1191 | pages[i]->mapping != inode->i_mapping) { | |
771ed689 CM |
1192 | ret = -EAGAIN; |
1193 | unlock_page(pages[i]); | |
1194 | page_cache_release(pages[i]); | |
1195 | goto done; | |
1196 | } | |
1197 | } | |
c8b97818 | 1198 | page_cache_release(pages[i]); |
771ed689 | 1199 | pages_locked++; |
c8b97818 | 1200 | } |
c8b97818 CM |
1201 | nrpages -= ret; |
1202 | index += ret; | |
1203 | cond_resched(); | |
1204 | } | |
1205 | ret = 0; | |
1206 | done: | |
1207 | if (ret && pages_locked) { | |
1208 | __unlock_for_delalloc(inode, locked_page, | |
1209 | delalloc_start, | |
1210 | ((u64)(start_index + pages_locked - 1)) << | |
1211 | PAGE_CACHE_SHIFT); | |
1212 | } | |
1213 | return ret; | |
1214 | } | |
1215 | ||
1216 | /* | |
1217 | * find a contiguous range of bytes in the file marked as delalloc, not | |
1218 | * more than 'max_bytes'. start and end are used to return the range, | |
1219 | * | |
1220 | * 1 is returned if we find something, 0 if nothing was in the tree | |
1221 | */ | |
1222 | static noinline u64 find_lock_delalloc_range(struct inode *inode, | |
1223 | struct extent_io_tree *tree, | |
1224 | struct page *locked_page, | |
1225 | u64 *start, u64 *end, | |
1226 | u64 max_bytes) | |
1227 | { | |
1228 | u64 delalloc_start; | |
1229 | u64 delalloc_end; | |
1230 | u64 found; | |
1231 | int ret; | |
1232 | int loops = 0; | |
1233 | ||
1234 | again: | |
1235 | /* step one, find a bunch of delalloc bytes starting at start */ | |
1236 | delalloc_start = *start; | |
1237 | delalloc_end = 0; | |
1238 | found = find_delalloc_range(tree, &delalloc_start, &delalloc_end, | |
1239 | max_bytes); | |
70b99e69 | 1240 | if (!found || delalloc_end <= *start) { |
c8b97818 CM |
1241 | *start = delalloc_start; |
1242 | *end = delalloc_end; | |
1243 | return found; | |
1244 | } | |
1245 | ||
70b99e69 CM |
1246 | /* |
1247 | * start comes from the offset of locked_page. We have to lock | |
1248 | * pages in order, so we can't process delalloc bytes before | |
1249 | * locked_page | |
1250 | */ | |
d397712b | 1251 | if (delalloc_start < *start) |
70b99e69 | 1252 | delalloc_start = *start; |
70b99e69 | 1253 | |
c8b97818 CM |
1254 | /* |
1255 | * make sure to limit the number of pages we try to lock down | |
1256 | * if we're looping. | |
1257 | */ | |
d397712b | 1258 | if (delalloc_end + 1 - delalloc_start > max_bytes && loops) |
771ed689 | 1259 | delalloc_end = delalloc_start + PAGE_CACHE_SIZE - 1; |
d397712b | 1260 | |
c8b97818 CM |
1261 | /* step two, lock all the pages after the page that has start */ |
1262 | ret = lock_delalloc_pages(inode, locked_page, | |
1263 | delalloc_start, delalloc_end); | |
1264 | if (ret == -EAGAIN) { | |
1265 | /* some of the pages are gone, lets avoid looping by | |
1266 | * shortening the size of the delalloc range we're searching | |
1267 | */ | |
1268 | if (!loops) { | |
1269 | unsigned long offset = (*start) & (PAGE_CACHE_SIZE - 1); | |
1270 | max_bytes = PAGE_CACHE_SIZE - offset; | |
1271 | loops = 1; | |
1272 | goto again; | |
1273 | } else { | |
1274 | found = 0; | |
1275 | goto out_failed; | |
1276 | } | |
1277 | } | |
1278 | BUG_ON(ret); | |
1279 | ||
1280 | /* step three, lock the state bits for the whole range */ | |
1281 | lock_extent(tree, delalloc_start, delalloc_end, GFP_NOFS); | |
1282 | ||
1283 | /* then test to make sure it is all still delalloc */ | |
1284 | ret = test_range_bit(tree, delalloc_start, delalloc_end, | |
1285 | EXTENT_DELALLOC, 1); | |
1286 | if (!ret) { | |
1287 | unlock_extent(tree, delalloc_start, delalloc_end, GFP_NOFS); | |
1288 | __unlock_for_delalloc(inode, locked_page, | |
1289 | delalloc_start, delalloc_end); | |
1290 | cond_resched(); | |
1291 | goto again; | |
1292 | } | |
1293 | *start = delalloc_start; | |
1294 | *end = delalloc_end; | |
1295 | out_failed: | |
1296 | return found; | |
1297 | } | |
1298 | ||
1299 | int extent_clear_unlock_delalloc(struct inode *inode, | |
1300 | struct extent_io_tree *tree, | |
1301 | u64 start, u64 end, struct page *locked_page, | |
771ed689 CM |
1302 | int unlock_pages, |
1303 | int clear_unlock, | |
1304 | int clear_delalloc, int clear_dirty, | |
1305 | int set_writeback, | |
c8b97818 CM |
1306 | int end_writeback) |
1307 | { | |
1308 | int ret; | |
1309 | struct page *pages[16]; | |
1310 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1311 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
1312 | unsigned long nr_pages = end_index - index + 1; | |
1313 | int i; | |
771ed689 | 1314 | int clear_bits = 0; |
c8b97818 | 1315 | |
771ed689 CM |
1316 | if (clear_unlock) |
1317 | clear_bits |= EXTENT_LOCKED; | |
c8b97818 CM |
1318 | if (clear_dirty) |
1319 | clear_bits |= EXTENT_DIRTY; | |
1320 | ||
771ed689 CM |
1321 | if (clear_delalloc) |
1322 | clear_bits |= EXTENT_DELALLOC; | |
1323 | ||
c8b97818 | 1324 | clear_extent_bit(tree, start, end, clear_bits, 1, 0, GFP_NOFS); |
771ed689 CM |
1325 | if (!(unlock_pages || clear_dirty || set_writeback || end_writeback)) |
1326 | return 0; | |
c8b97818 | 1327 | |
d397712b | 1328 | while (nr_pages > 0) { |
c8b97818 | 1329 | ret = find_get_pages_contig(inode->i_mapping, index, |
5b050f04 CM |
1330 | min_t(unsigned long, |
1331 | nr_pages, ARRAY_SIZE(pages)), pages); | |
c8b97818 CM |
1332 | for (i = 0; i < ret; i++) { |
1333 | if (pages[i] == locked_page) { | |
1334 | page_cache_release(pages[i]); | |
1335 | continue; | |
1336 | } | |
1337 | if (clear_dirty) | |
1338 | clear_page_dirty_for_io(pages[i]); | |
1339 | if (set_writeback) | |
1340 | set_page_writeback(pages[i]); | |
1341 | if (end_writeback) | |
1342 | end_page_writeback(pages[i]); | |
771ed689 CM |
1343 | if (unlock_pages) |
1344 | unlock_page(pages[i]); | |
c8b97818 CM |
1345 | page_cache_release(pages[i]); |
1346 | } | |
1347 | nr_pages -= ret; | |
1348 | index += ret; | |
1349 | cond_resched(); | |
1350 | } | |
1351 | return 0; | |
1352 | } | |
c8b97818 | 1353 | |
d352ac68 CM |
1354 | /* |
1355 | * count the number of bytes in the tree that have a given bit(s) | |
1356 | * set. This can be fairly slow, except for EXTENT_DIRTY which is | |
1357 | * cached. The total number found is returned. | |
1358 | */ | |
d1310b2e CM |
1359 | u64 count_range_bits(struct extent_io_tree *tree, |
1360 | u64 *start, u64 search_end, u64 max_bytes, | |
1361 | unsigned long bits) | |
1362 | { | |
1363 | struct rb_node *node; | |
1364 | struct extent_state *state; | |
1365 | u64 cur_start = *start; | |
1366 | u64 total_bytes = 0; | |
1367 | int found = 0; | |
1368 | ||
1369 | if (search_end <= cur_start) { | |
d1310b2e CM |
1370 | WARN_ON(1); |
1371 | return 0; | |
1372 | } | |
1373 | ||
cad321ad | 1374 | spin_lock(&tree->lock); |
d1310b2e CM |
1375 | if (cur_start == 0 && bits == EXTENT_DIRTY) { |
1376 | total_bytes = tree->dirty_bytes; | |
1377 | goto out; | |
1378 | } | |
1379 | /* | |
1380 | * this search will find all the extents that end after | |
1381 | * our range starts. | |
1382 | */ | |
80ea96b1 | 1383 | node = tree_search(tree, cur_start); |
d397712b | 1384 | if (!node) |
d1310b2e | 1385 | goto out; |
d1310b2e | 1386 | |
d397712b | 1387 | while (1) { |
d1310b2e CM |
1388 | state = rb_entry(node, struct extent_state, rb_node); |
1389 | if (state->start > search_end) | |
1390 | break; | |
1391 | if (state->end >= cur_start && (state->state & bits)) { | |
1392 | total_bytes += min(search_end, state->end) + 1 - | |
1393 | max(cur_start, state->start); | |
1394 | if (total_bytes >= max_bytes) | |
1395 | break; | |
1396 | if (!found) { | |
1397 | *start = state->start; | |
1398 | found = 1; | |
1399 | } | |
1400 | } | |
1401 | node = rb_next(node); | |
1402 | if (!node) | |
1403 | break; | |
1404 | } | |
1405 | out: | |
cad321ad | 1406 | spin_unlock(&tree->lock); |
d1310b2e CM |
1407 | return total_bytes; |
1408 | } | |
b2950863 CH |
1409 | |
1410 | #if 0 | |
d1310b2e CM |
1411 | /* |
1412 | * helper function to lock both pages and extents in the tree. | |
1413 | * pages must be locked first. | |
1414 | */ | |
b2950863 | 1415 | static int lock_range(struct extent_io_tree *tree, u64 start, u64 end) |
d1310b2e CM |
1416 | { |
1417 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1418 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
1419 | struct page *page; | |
1420 | int err; | |
1421 | ||
1422 | while (index <= end_index) { | |
1423 | page = grab_cache_page(tree->mapping, index); | |
1424 | if (!page) { | |
1425 | err = -ENOMEM; | |
1426 | goto failed; | |
1427 | } | |
1428 | if (IS_ERR(page)) { | |
1429 | err = PTR_ERR(page); | |
1430 | goto failed; | |
1431 | } | |
1432 | index++; | |
1433 | } | |
1434 | lock_extent(tree, start, end, GFP_NOFS); | |
1435 | return 0; | |
1436 | ||
1437 | failed: | |
1438 | /* | |
1439 | * we failed above in getting the page at 'index', so we undo here | |
1440 | * up to but not including the page at 'index' | |
1441 | */ | |
1442 | end_index = index; | |
1443 | index = start >> PAGE_CACHE_SHIFT; | |
1444 | while (index < end_index) { | |
1445 | page = find_get_page(tree->mapping, index); | |
1446 | unlock_page(page); | |
1447 | page_cache_release(page); | |
1448 | index++; | |
1449 | } | |
1450 | return err; | |
1451 | } | |
d1310b2e CM |
1452 | |
1453 | /* | |
1454 | * helper function to unlock both pages and extents in the tree. | |
1455 | */ | |
b2950863 | 1456 | static int unlock_range(struct extent_io_tree *tree, u64 start, u64 end) |
d1310b2e CM |
1457 | { |
1458 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1459 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
1460 | struct page *page; | |
1461 | ||
1462 | while (index <= end_index) { | |
1463 | page = find_get_page(tree->mapping, index); | |
1464 | unlock_page(page); | |
1465 | page_cache_release(page); | |
1466 | index++; | |
1467 | } | |
1468 | unlock_extent(tree, start, end, GFP_NOFS); | |
1469 | return 0; | |
1470 | } | |
b2950863 | 1471 | #endif |
d1310b2e | 1472 | |
d352ac68 CM |
1473 | /* |
1474 | * set the private field for a given byte offset in the tree. If there isn't | |
1475 | * an extent_state there already, this does nothing. | |
1476 | */ | |
d1310b2e CM |
1477 | int set_state_private(struct extent_io_tree *tree, u64 start, u64 private) |
1478 | { | |
1479 | struct rb_node *node; | |
1480 | struct extent_state *state; | |
1481 | int ret = 0; | |
1482 | ||
cad321ad | 1483 | spin_lock(&tree->lock); |
d1310b2e CM |
1484 | /* |
1485 | * this search will find all the extents that end after | |
1486 | * our range starts. | |
1487 | */ | |
80ea96b1 | 1488 | node = tree_search(tree, start); |
2b114d1d | 1489 | if (!node) { |
d1310b2e CM |
1490 | ret = -ENOENT; |
1491 | goto out; | |
1492 | } | |
1493 | state = rb_entry(node, struct extent_state, rb_node); | |
1494 | if (state->start != start) { | |
1495 | ret = -ENOENT; | |
1496 | goto out; | |
1497 | } | |
1498 | state->private = private; | |
1499 | out: | |
cad321ad | 1500 | spin_unlock(&tree->lock); |
d1310b2e CM |
1501 | return ret; |
1502 | } | |
1503 | ||
1504 | int get_state_private(struct extent_io_tree *tree, u64 start, u64 *private) | |
1505 | { | |
1506 | struct rb_node *node; | |
1507 | struct extent_state *state; | |
1508 | int ret = 0; | |
1509 | ||
cad321ad | 1510 | spin_lock(&tree->lock); |
d1310b2e CM |
1511 | /* |
1512 | * this search will find all the extents that end after | |
1513 | * our range starts. | |
1514 | */ | |
80ea96b1 | 1515 | node = tree_search(tree, start); |
2b114d1d | 1516 | if (!node) { |
d1310b2e CM |
1517 | ret = -ENOENT; |
1518 | goto out; | |
1519 | } | |
1520 | state = rb_entry(node, struct extent_state, rb_node); | |
1521 | if (state->start != start) { | |
1522 | ret = -ENOENT; | |
1523 | goto out; | |
1524 | } | |
1525 | *private = state->private; | |
1526 | out: | |
cad321ad | 1527 | spin_unlock(&tree->lock); |
d1310b2e CM |
1528 | return ret; |
1529 | } | |
1530 | ||
1531 | /* | |
1532 | * searches a range in the state tree for a given mask. | |
70dec807 | 1533 | * If 'filled' == 1, this returns 1 only if every extent in the tree |
d1310b2e CM |
1534 | * has the bits set. Otherwise, 1 is returned if any bit in the |
1535 | * range is found set. | |
1536 | */ | |
1537 | int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end, | |
1538 | int bits, int filled) | |
1539 | { | |
1540 | struct extent_state *state = NULL; | |
1541 | struct rb_node *node; | |
1542 | int bitset = 0; | |
d1310b2e | 1543 | |
cad321ad | 1544 | spin_lock(&tree->lock); |
80ea96b1 | 1545 | node = tree_search(tree, start); |
d1310b2e CM |
1546 | while (node && start <= end) { |
1547 | state = rb_entry(node, struct extent_state, rb_node); | |
1548 | ||
1549 | if (filled && state->start > start) { | |
1550 | bitset = 0; | |
1551 | break; | |
1552 | } | |
1553 | ||
1554 | if (state->start > end) | |
1555 | break; | |
1556 | ||
1557 | if (state->state & bits) { | |
1558 | bitset = 1; | |
1559 | if (!filled) | |
1560 | break; | |
1561 | } else if (filled) { | |
1562 | bitset = 0; | |
1563 | break; | |
1564 | } | |
1565 | start = state->end + 1; | |
1566 | if (start > end) | |
1567 | break; | |
1568 | node = rb_next(node); | |
1569 | if (!node) { | |
1570 | if (filled) | |
1571 | bitset = 0; | |
1572 | break; | |
1573 | } | |
1574 | } | |
cad321ad | 1575 | spin_unlock(&tree->lock); |
d1310b2e CM |
1576 | return bitset; |
1577 | } | |
d1310b2e CM |
1578 | |
1579 | /* | |
1580 | * helper function to set a given page up to date if all the | |
1581 | * extents in the tree for that page are up to date | |
1582 | */ | |
1583 | static int check_page_uptodate(struct extent_io_tree *tree, | |
1584 | struct page *page) | |
1585 | { | |
1586 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
1587 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
1588 | if (test_range_bit(tree, start, end, EXTENT_UPTODATE, 1)) | |
1589 | SetPageUptodate(page); | |
1590 | return 0; | |
1591 | } | |
1592 | ||
1593 | /* | |
1594 | * helper function to unlock a page if all the extents in the tree | |
1595 | * for that page are unlocked | |
1596 | */ | |
1597 | static int check_page_locked(struct extent_io_tree *tree, | |
1598 | struct page *page) | |
1599 | { | |
1600 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
1601 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
1602 | if (!test_range_bit(tree, start, end, EXTENT_LOCKED, 0)) | |
1603 | unlock_page(page); | |
1604 | return 0; | |
1605 | } | |
1606 | ||
1607 | /* | |
1608 | * helper function to end page writeback if all the extents | |
1609 | * in the tree for that page are done with writeback | |
1610 | */ | |
1611 | static int check_page_writeback(struct extent_io_tree *tree, | |
1612 | struct page *page) | |
1613 | { | |
1614 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
1615 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
1616 | if (!test_range_bit(tree, start, end, EXTENT_WRITEBACK, 0)) | |
1617 | end_page_writeback(page); | |
1618 | return 0; | |
1619 | } | |
1620 | ||
1621 | /* lots and lots of room for performance fixes in the end_bio funcs */ | |
1622 | ||
1623 | /* | |
1624 | * after a writepage IO is done, we need to: | |
1625 | * clear the uptodate bits on error | |
1626 | * clear the writeback bits in the extent tree for this IO | |
1627 | * end_page_writeback if the page has no more pending IO | |
1628 | * | |
1629 | * Scheduling is not allowed, so the extent state tree is expected | |
1630 | * to have one and only one object corresponding to this IO. | |
1631 | */ | |
d1310b2e | 1632 | static void end_bio_extent_writepage(struct bio *bio, int err) |
d1310b2e | 1633 | { |
1259ab75 | 1634 | int uptodate = err == 0; |
d1310b2e | 1635 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; |
902b22f3 | 1636 | struct extent_io_tree *tree; |
d1310b2e CM |
1637 | u64 start; |
1638 | u64 end; | |
1639 | int whole_page; | |
1259ab75 | 1640 | int ret; |
d1310b2e | 1641 | |
d1310b2e CM |
1642 | do { |
1643 | struct page *page = bvec->bv_page; | |
902b22f3 DW |
1644 | tree = &BTRFS_I(page->mapping->host)->io_tree; |
1645 | ||
d1310b2e CM |
1646 | start = ((u64)page->index << PAGE_CACHE_SHIFT) + |
1647 | bvec->bv_offset; | |
1648 | end = start + bvec->bv_len - 1; | |
1649 | ||
1650 | if (bvec->bv_offset == 0 && bvec->bv_len == PAGE_CACHE_SIZE) | |
1651 | whole_page = 1; | |
1652 | else | |
1653 | whole_page = 0; | |
1654 | ||
1655 | if (--bvec >= bio->bi_io_vec) | |
1656 | prefetchw(&bvec->bv_page->flags); | |
1259ab75 CM |
1657 | if (tree->ops && tree->ops->writepage_end_io_hook) { |
1658 | ret = tree->ops->writepage_end_io_hook(page, start, | |
902b22f3 | 1659 | end, NULL, uptodate); |
1259ab75 CM |
1660 | if (ret) |
1661 | uptodate = 0; | |
1662 | } | |
1663 | ||
1664 | if (!uptodate && tree->ops && | |
1665 | tree->ops->writepage_io_failed_hook) { | |
1666 | ret = tree->ops->writepage_io_failed_hook(bio, page, | |
902b22f3 | 1667 | start, end, NULL); |
1259ab75 | 1668 | if (ret == 0) { |
1259ab75 CM |
1669 | uptodate = (err == 0); |
1670 | continue; | |
1671 | } | |
1672 | } | |
1673 | ||
d1310b2e CM |
1674 | if (!uptodate) { |
1675 | clear_extent_uptodate(tree, start, end, GFP_ATOMIC); | |
1676 | ClearPageUptodate(page); | |
1677 | SetPageError(page); | |
1678 | } | |
70dec807 | 1679 | |
902b22f3 | 1680 | clear_extent_writeback(tree, start, end, GFP_ATOMIC); |
d1310b2e CM |
1681 | |
1682 | if (whole_page) | |
1683 | end_page_writeback(page); | |
1684 | else | |
1685 | check_page_writeback(tree, page); | |
d1310b2e | 1686 | } while (bvec >= bio->bi_io_vec); |
2b1f55b0 | 1687 | |
d1310b2e | 1688 | bio_put(bio); |
d1310b2e CM |
1689 | } |
1690 | ||
1691 | /* | |
1692 | * after a readpage IO is done, we need to: | |
1693 | * clear the uptodate bits on error | |
1694 | * set the uptodate bits if things worked | |
1695 | * set the page up to date if all extents in the tree are uptodate | |
1696 | * clear the lock bit in the extent tree | |
1697 | * unlock the page if there are no other extents locked for it | |
1698 | * | |
1699 | * Scheduling is not allowed, so the extent state tree is expected | |
1700 | * to have one and only one object corresponding to this IO. | |
1701 | */ | |
d1310b2e | 1702 | static void end_bio_extent_readpage(struct bio *bio, int err) |
d1310b2e CM |
1703 | { |
1704 | int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); | |
1705 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; | |
902b22f3 | 1706 | struct extent_io_tree *tree; |
d1310b2e CM |
1707 | u64 start; |
1708 | u64 end; | |
1709 | int whole_page; | |
1710 | int ret; | |
1711 | ||
d20f7043 CM |
1712 | if (err) |
1713 | uptodate = 0; | |
1714 | ||
d1310b2e CM |
1715 | do { |
1716 | struct page *page = bvec->bv_page; | |
902b22f3 DW |
1717 | tree = &BTRFS_I(page->mapping->host)->io_tree; |
1718 | ||
d1310b2e CM |
1719 | start = ((u64)page->index << PAGE_CACHE_SHIFT) + |
1720 | bvec->bv_offset; | |
1721 | end = start + bvec->bv_len - 1; | |
1722 | ||
1723 | if (bvec->bv_offset == 0 && bvec->bv_len == PAGE_CACHE_SIZE) | |
1724 | whole_page = 1; | |
1725 | else | |
1726 | whole_page = 0; | |
1727 | ||
1728 | if (--bvec >= bio->bi_io_vec) | |
1729 | prefetchw(&bvec->bv_page->flags); | |
1730 | ||
1731 | if (uptodate && tree->ops && tree->ops->readpage_end_io_hook) { | |
70dec807 | 1732 | ret = tree->ops->readpage_end_io_hook(page, start, end, |
902b22f3 | 1733 | NULL); |
d1310b2e CM |
1734 | if (ret) |
1735 | uptodate = 0; | |
1736 | } | |
7e38326f CM |
1737 | if (!uptodate && tree->ops && |
1738 | tree->ops->readpage_io_failed_hook) { | |
1739 | ret = tree->ops->readpage_io_failed_hook(bio, page, | |
902b22f3 | 1740 | start, end, NULL); |
7e38326f | 1741 | if (ret == 0) { |
3b951516 CM |
1742 | uptodate = |
1743 | test_bit(BIO_UPTODATE, &bio->bi_flags); | |
d20f7043 CM |
1744 | if (err) |
1745 | uptodate = 0; | |
7e38326f CM |
1746 | continue; |
1747 | } | |
1748 | } | |
d1310b2e | 1749 | |
771ed689 | 1750 | if (uptodate) { |
902b22f3 DW |
1751 | set_extent_uptodate(tree, start, end, |
1752 | GFP_ATOMIC); | |
771ed689 | 1753 | } |
902b22f3 | 1754 | unlock_extent(tree, start, end, GFP_ATOMIC); |
d1310b2e | 1755 | |
70dec807 CM |
1756 | if (whole_page) { |
1757 | if (uptodate) { | |
1758 | SetPageUptodate(page); | |
1759 | } else { | |
1760 | ClearPageUptodate(page); | |
1761 | SetPageError(page); | |
1762 | } | |
d1310b2e | 1763 | unlock_page(page); |
70dec807 CM |
1764 | } else { |
1765 | if (uptodate) { | |
1766 | check_page_uptodate(tree, page); | |
1767 | } else { | |
1768 | ClearPageUptodate(page); | |
1769 | SetPageError(page); | |
1770 | } | |
d1310b2e | 1771 | check_page_locked(tree, page); |
70dec807 | 1772 | } |
d1310b2e CM |
1773 | } while (bvec >= bio->bi_io_vec); |
1774 | ||
1775 | bio_put(bio); | |
d1310b2e CM |
1776 | } |
1777 | ||
1778 | /* | |
1779 | * IO done from prepare_write is pretty simple, we just unlock | |
1780 | * the structs in the extent tree when done, and set the uptodate bits | |
1781 | * as appropriate. | |
1782 | */ | |
d1310b2e | 1783 | static void end_bio_extent_preparewrite(struct bio *bio, int err) |
d1310b2e CM |
1784 | { |
1785 | const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); | |
1786 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; | |
902b22f3 | 1787 | struct extent_io_tree *tree; |
d1310b2e CM |
1788 | u64 start; |
1789 | u64 end; | |
1790 | ||
d1310b2e CM |
1791 | do { |
1792 | struct page *page = bvec->bv_page; | |
902b22f3 DW |
1793 | tree = &BTRFS_I(page->mapping->host)->io_tree; |
1794 | ||
d1310b2e CM |
1795 | start = ((u64)page->index << PAGE_CACHE_SHIFT) + |
1796 | bvec->bv_offset; | |
1797 | end = start + bvec->bv_len - 1; | |
1798 | ||
1799 | if (--bvec >= bio->bi_io_vec) | |
1800 | prefetchw(&bvec->bv_page->flags); | |
1801 | ||
1802 | if (uptodate) { | |
1803 | set_extent_uptodate(tree, start, end, GFP_ATOMIC); | |
1804 | } else { | |
1805 | ClearPageUptodate(page); | |
1806 | SetPageError(page); | |
1807 | } | |
1808 | ||
1809 | unlock_extent(tree, start, end, GFP_ATOMIC); | |
1810 | ||
1811 | } while (bvec >= bio->bi_io_vec); | |
1812 | ||
1813 | bio_put(bio); | |
d1310b2e CM |
1814 | } |
1815 | ||
1816 | static struct bio * | |
1817 | extent_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs, | |
1818 | gfp_t gfp_flags) | |
1819 | { | |
1820 | struct bio *bio; | |
1821 | ||
1822 | bio = bio_alloc(gfp_flags, nr_vecs); | |
1823 | ||
1824 | if (bio == NULL && (current->flags & PF_MEMALLOC)) { | |
1825 | while (!bio && (nr_vecs /= 2)) | |
1826 | bio = bio_alloc(gfp_flags, nr_vecs); | |
1827 | } | |
1828 | ||
1829 | if (bio) { | |
e1c4b745 | 1830 | bio->bi_size = 0; |
d1310b2e CM |
1831 | bio->bi_bdev = bdev; |
1832 | bio->bi_sector = first_sector; | |
1833 | } | |
1834 | return bio; | |
1835 | } | |
1836 | ||
c8b97818 CM |
1837 | static int submit_one_bio(int rw, struct bio *bio, int mirror_num, |
1838 | unsigned long bio_flags) | |
d1310b2e | 1839 | { |
d1310b2e | 1840 | int ret = 0; |
70dec807 CM |
1841 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; |
1842 | struct page *page = bvec->bv_page; | |
1843 | struct extent_io_tree *tree = bio->bi_private; | |
70dec807 CM |
1844 | u64 start; |
1845 | u64 end; | |
1846 | ||
1847 | start = ((u64)page->index << PAGE_CACHE_SHIFT) + bvec->bv_offset; | |
1848 | end = start + bvec->bv_len - 1; | |
1849 | ||
902b22f3 | 1850 | bio->bi_private = NULL; |
d1310b2e CM |
1851 | |
1852 | bio_get(bio); | |
1853 | ||
065631f6 | 1854 | if (tree->ops && tree->ops->submit_bio_hook) |
f188591e | 1855 | tree->ops->submit_bio_hook(page->mapping->host, rw, bio, |
c8b97818 | 1856 | mirror_num, bio_flags); |
0b86a832 CM |
1857 | else |
1858 | submit_bio(rw, bio); | |
d1310b2e CM |
1859 | if (bio_flagged(bio, BIO_EOPNOTSUPP)) |
1860 | ret = -EOPNOTSUPP; | |
1861 | bio_put(bio); | |
1862 | return ret; | |
1863 | } | |
1864 | ||
1865 | static int submit_extent_page(int rw, struct extent_io_tree *tree, | |
1866 | struct page *page, sector_t sector, | |
1867 | size_t size, unsigned long offset, | |
1868 | struct block_device *bdev, | |
1869 | struct bio **bio_ret, | |
1870 | unsigned long max_pages, | |
f188591e | 1871 | bio_end_io_t end_io_func, |
c8b97818 CM |
1872 | int mirror_num, |
1873 | unsigned long prev_bio_flags, | |
1874 | unsigned long bio_flags) | |
d1310b2e CM |
1875 | { |
1876 | int ret = 0; | |
1877 | struct bio *bio; | |
1878 | int nr; | |
c8b97818 CM |
1879 | int contig = 0; |
1880 | int this_compressed = bio_flags & EXTENT_BIO_COMPRESSED; | |
1881 | int old_compressed = prev_bio_flags & EXTENT_BIO_COMPRESSED; | |
5b050f04 | 1882 | size_t page_size = min_t(size_t, size, PAGE_CACHE_SIZE); |
d1310b2e CM |
1883 | |
1884 | if (bio_ret && *bio_ret) { | |
1885 | bio = *bio_ret; | |
c8b97818 CM |
1886 | if (old_compressed) |
1887 | contig = bio->bi_sector == sector; | |
1888 | else | |
1889 | contig = bio->bi_sector + (bio->bi_size >> 9) == | |
1890 | sector; | |
1891 | ||
1892 | if (prev_bio_flags != bio_flags || !contig || | |
239b14b3 | 1893 | (tree->ops && tree->ops->merge_bio_hook && |
c8b97818 CM |
1894 | tree->ops->merge_bio_hook(page, offset, page_size, bio, |
1895 | bio_flags)) || | |
1896 | bio_add_page(bio, page, page_size, offset) < page_size) { | |
1897 | ret = submit_one_bio(rw, bio, mirror_num, | |
1898 | prev_bio_flags); | |
d1310b2e CM |
1899 | bio = NULL; |
1900 | } else { | |
1901 | return 0; | |
1902 | } | |
1903 | } | |
c8b97818 CM |
1904 | if (this_compressed) |
1905 | nr = BIO_MAX_PAGES; | |
1906 | else | |
1907 | nr = bio_get_nr_vecs(bdev); | |
1908 | ||
d1310b2e | 1909 | bio = extent_bio_alloc(bdev, sector, nr, GFP_NOFS | __GFP_HIGH); |
70dec807 | 1910 | |
c8b97818 | 1911 | bio_add_page(bio, page, page_size, offset); |
d1310b2e CM |
1912 | bio->bi_end_io = end_io_func; |
1913 | bio->bi_private = tree; | |
70dec807 | 1914 | |
d397712b | 1915 | if (bio_ret) |
d1310b2e | 1916 | *bio_ret = bio; |
d397712b | 1917 | else |
c8b97818 | 1918 | ret = submit_one_bio(rw, bio, mirror_num, bio_flags); |
d1310b2e CM |
1919 | |
1920 | return ret; | |
1921 | } | |
1922 | ||
1923 | void set_page_extent_mapped(struct page *page) | |
1924 | { | |
1925 | if (!PagePrivate(page)) { | |
1926 | SetPagePrivate(page); | |
d1310b2e | 1927 | page_cache_get(page); |
6af118ce | 1928 | set_page_private(page, EXTENT_PAGE_PRIVATE); |
d1310b2e CM |
1929 | } |
1930 | } | |
1931 | ||
b2950863 | 1932 | static void set_page_extent_head(struct page *page, unsigned long len) |
d1310b2e CM |
1933 | { |
1934 | set_page_private(page, EXTENT_PAGE_PRIVATE_FIRST_PAGE | len << 2); | |
1935 | } | |
1936 | ||
1937 | /* | |
1938 | * basic readpage implementation. Locked extent state structs are inserted | |
1939 | * into the tree that are removed when the IO is done (by the end_io | |
1940 | * handlers) | |
1941 | */ | |
1942 | static int __extent_read_full_page(struct extent_io_tree *tree, | |
1943 | struct page *page, | |
1944 | get_extent_t *get_extent, | |
c8b97818 CM |
1945 | struct bio **bio, int mirror_num, |
1946 | unsigned long *bio_flags) | |
d1310b2e CM |
1947 | { |
1948 | struct inode *inode = page->mapping->host; | |
1949 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
1950 | u64 page_end = start + PAGE_CACHE_SIZE - 1; | |
1951 | u64 end; | |
1952 | u64 cur = start; | |
1953 | u64 extent_offset; | |
1954 | u64 last_byte = i_size_read(inode); | |
1955 | u64 block_start; | |
1956 | u64 cur_end; | |
1957 | sector_t sector; | |
1958 | struct extent_map *em; | |
1959 | struct block_device *bdev; | |
1960 | int ret; | |
1961 | int nr = 0; | |
1962 | size_t page_offset = 0; | |
1963 | size_t iosize; | |
c8b97818 | 1964 | size_t disk_io_size; |
d1310b2e | 1965 | size_t blocksize = inode->i_sb->s_blocksize; |
c8b97818 | 1966 | unsigned long this_bio_flag = 0; |
d1310b2e CM |
1967 | |
1968 | set_page_extent_mapped(page); | |
1969 | ||
1970 | end = page_end; | |
1971 | lock_extent(tree, start, end, GFP_NOFS); | |
1972 | ||
c8b97818 CM |
1973 | if (page->index == last_byte >> PAGE_CACHE_SHIFT) { |
1974 | char *userpage; | |
1975 | size_t zero_offset = last_byte & (PAGE_CACHE_SIZE - 1); | |
1976 | ||
1977 | if (zero_offset) { | |
1978 | iosize = PAGE_CACHE_SIZE - zero_offset; | |
1979 | userpage = kmap_atomic(page, KM_USER0); | |
1980 | memset(userpage + zero_offset, 0, iosize); | |
1981 | flush_dcache_page(page); | |
1982 | kunmap_atomic(userpage, KM_USER0); | |
1983 | } | |
1984 | } | |
d1310b2e CM |
1985 | while (cur <= end) { |
1986 | if (cur >= last_byte) { | |
1987 | char *userpage; | |
1988 | iosize = PAGE_CACHE_SIZE - page_offset; | |
1989 | userpage = kmap_atomic(page, KM_USER0); | |
1990 | memset(userpage + page_offset, 0, iosize); | |
1991 | flush_dcache_page(page); | |
1992 | kunmap_atomic(userpage, KM_USER0); | |
1993 | set_extent_uptodate(tree, cur, cur + iosize - 1, | |
1994 | GFP_NOFS); | |
1995 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); | |
1996 | break; | |
1997 | } | |
1998 | em = get_extent(inode, page, page_offset, cur, | |
1999 | end - cur + 1, 0); | |
2000 | if (IS_ERR(em) || !em) { | |
2001 | SetPageError(page); | |
2002 | unlock_extent(tree, cur, end, GFP_NOFS); | |
2003 | break; | |
2004 | } | |
d1310b2e CM |
2005 | extent_offset = cur - em->start; |
2006 | BUG_ON(extent_map_end(em) <= cur); | |
2007 | BUG_ON(end < cur); | |
2008 | ||
c8b97818 CM |
2009 | if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) |
2010 | this_bio_flag = EXTENT_BIO_COMPRESSED; | |
2011 | ||
d1310b2e CM |
2012 | iosize = min(extent_map_end(em) - cur, end - cur + 1); |
2013 | cur_end = min(extent_map_end(em) - 1, end); | |
2014 | iosize = (iosize + blocksize - 1) & ~((u64)blocksize - 1); | |
c8b97818 CM |
2015 | if (this_bio_flag & EXTENT_BIO_COMPRESSED) { |
2016 | disk_io_size = em->block_len; | |
2017 | sector = em->block_start >> 9; | |
2018 | } else { | |
2019 | sector = (em->block_start + extent_offset) >> 9; | |
2020 | disk_io_size = iosize; | |
2021 | } | |
d1310b2e CM |
2022 | bdev = em->bdev; |
2023 | block_start = em->block_start; | |
d899e052 YZ |
2024 | if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) |
2025 | block_start = EXTENT_MAP_HOLE; | |
d1310b2e CM |
2026 | free_extent_map(em); |
2027 | em = NULL; | |
2028 | ||
2029 | /* we've found a hole, just zero and go on */ | |
2030 | if (block_start == EXTENT_MAP_HOLE) { | |
2031 | char *userpage; | |
2032 | userpage = kmap_atomic(page, KM_USER0); | |
2033 | memset(userpage + page_offset, 0, iosize); | |
2034 | flush_dcache_page(page); | |
2035 | kunmap_atomic(userpage, KM_USER0); | |
2036 | ||
2037 | set_extent_uptodate(tree, cur, cur + iosize - 1, | |
2038 | GFP_NOFS); | |
2039 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); | |
2040 | cur = cur + iosize; | |
2041 | page_offset += iosize; | |
2042 | continue; | |
2043 | } | |
2044 | /* the get_extent function already copied into the page */ | |
2045 | if (test_range_bit(tree, cur, cur_end, EXTENT_UPTODATE, 1)) { | |
a1b32a59 | 2046 | check_page_uptodate(tree, page); |
d1310b2e CM |
2047 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); |
2048 | cur = cur + iosize; | |
2049 | page_offset += iosize; | |
2050 | continue; | |
2051 | } | |
70dec807 CM |
2052 | /* we have an inline extent but it didn't get marked up |
2053 | * to date. Error out | |
2054 | */ | |
2055 | if (block_start == EXTENT_MAP_INLINE) { | |
2056 | SetPageError(page); | |
2057 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); | |
2058 | cur = cur + iosize; | |
2059 | page_offset += iosize; | |
2060 | continue; | |
2061 | } | |
d1310b2e CM |
2062 | |
2063 | ret = 0; | |
2064 | if (tree->ops && tree->ops->readpage_io_hook) { | |
2065 | ret = tree->ops->readpage_io_hook(page, cur, | |
2066 | cur + iosize - 1); | |
2067 | } | |
2068 | if (!ret) { | |
89642229 CM |
2069 | unsigned long pnr = (last_byte >> PAGE_CACHE_SHIFT) + 1; |
2070 | pnr -= page->index; | |
d1310b2e | 2071 | ret = submit_extent_page(READ, tree, page, |
c8b97818 | 2072 | sector, disk_io_size, page_offset, |
89642229 | 2073 | bdev, bio, pnr, |
c8b97818 CM |
2074 | end_bio_extent_readpage, mirror_num, |
2075 | *bio_flags, | |
2076 | this_bio_flag); | |
89642229 | 2077 | nr++; |
c8b97818 | 2078 | *bio_flags = this_bio_flag; |
d1310b2e CM |
2079 | } |
2080 | if (ret) | |
2081 | SetPageError(page); | |
2082 | cur = cur + iosize; | |
2083 | page_offset += iosize; | |
d1310b2e CM |
2084 | } |
2085 | if (!nr) { | |
2086 | if (!PageError(page)) | |
2087 | SetPageUptodate(page); | |
2088 | unlock_page(page); | |
2089 | } | |
2090 | return 0; | |
2091 | } | |
2092 | ||
2093 | int extent_read_full_page(struct extent_io_tree *tree, struct page *page, | |
2094 | get_extent_t *get_extent) | |
2095 | { | |
2096 | struct bio *bio = NULL; | |
c8b97818 | 2097 | unsigned long bio_flags = 0; |
d1310b2e CM |
2098 | int ret; |
2099 | ||
c8b97818 CM |
2100 | ret = __extent_read_full_page(tree, page, get_extent, &bio, 0, |
2101 | &bio_flags); | |
d1310b2e | 2102 | if (bio) |
c8b97818 | 2103 | submit_one_bio(READ, bio, 0, bio_flags); |
d1310b2e CM |
2104 | return ret; |
2105 | } | |
d1310b2e CM |
2106 | |
2107 | /* | |
2108 | * the writepage semantics are similar to regular writepage. extent | |
2109 | * records are inserted to lock ranges in the tree, and as dirty areas | |
2110 | * are found, they are marked writeback. Then the lock bits are removed | |
2111 | * and the end_io handler clears the writeback ranges | |
2112 | */ | |
2113 | static int __extent_writepage(struct page *page, struct writeback_control *wbc, | |
2114 | void *data) | |
2115 | { | |
2116 | struct inode *inode = page->mapping->host; | |
2117 | struct extent_page_data *epd = data; | |
2118 | struct extent_io_tree *tree = epd->tree; | |
2119 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
2120 | u64 delalloc_start; | |
2121 | u64 page_end = start + PAGE_CACHE_SIZE - 1; | |
2122 | u64 end; | |
2123 | u64 cur = start; | |
2124 | u64 extent_offset; | |
2125 | u64 last_byte = i_size_read(inode); | |
2126 | u64 block_start; | |
2127 | u64 iosize; | |
e6dcd2dc | 2128 | u64 unlock_start; |
d1310b2e CM |
2129 | sector_t sector; |
2130 | struct extent_map *em; | |
2131 | struct block_device *bdev; | |
2132 | int ret; | |
2133 | int nr = 0; | |
7f3c74fb | 2134 | size_t pg_offset = 0; |
d1310b2e CM |
2135 | size_t blocksize; |
2136 | loff_t i_size = i_size_read(inode); | |
2137 | unsigned long end_index = i_size >> PAGE_CACHE_SHIFT; | |
2138 | u64 nr_delalloc; | |
2139 | u64 delalloc_end; | |
c8b97818 CM |
2140 | int page_started; |
2141 | int compressed; | |
ffbd517d | 2142 | int write_flags; |
771ed689 | 2143 | unsigned long nr_written = 0; |
d1310b2e | 2144 | |
ffbd517d CM |
2145 | if (wbc->sync_mode == WB_SYNC_ALL) |
2146 | write_flags = WRITE_SYNC_PLUG; | |
2147 | else | |
2148 | write_flags = WRITE; | |
2149 | ||
d1310b2e | 2150 | WARN_ON(!PageLocked(page)); |
7f3c74fb | 2151 | pg_offset = i_size & (PAGE_CACHE_SIZE - 1); |
211c17f5 | 2152 | if (page->index > end_index || |
7f3c74fb | 2153 | (page->index == end_index && !pg_offset)) { |
39be25cd | 2154 | page->mapping->a_ops->invalidatepage(page, 0); |
d1310b2e CM |
2155 | unlock_page(page); |
2156 | return 0; | |
2157 | } | |
2158 | ||
2159 | if (page->index == end_index) { | |
2160 | char *userpage; | |
2161 | ||
d1310b2e | 2162 | userpage = kmap_atomic(page, KM_USER0); |
7f3c74fb CM |
2163 | memset(userpage + pg_offset, 0, |
2164 | PAGE_CACHE_SIZE - pg_offset); | |
d1310b2e | 2165 | kunmap_atomic(userpage, KM_USER0); |
211c17f5 | 2166 | flush_dcache_page(page); |
d1310b2e | 2167 | } |
7f3c74fb | 2168 | pg_offset = 0; |
d1310b2e CM |
2169 | |
2170 | set_page_extent_mapped(page); | |
2171 | ||
2172 | delalloc_start = start; | |
2173 | delalloc_end = 0; | |
c8b97818 | 2174 | page_started = 0; |
771ed689 | 2175 | if (!epd->extent_locked) { |
d397712b | 2176 | while (delalloc_end < page_end) { |
771ed689 | 2177 | nr_delalloc = find_lock_delalloc_range(inode, tree, |
c8b97818 CM |
2178 | page, |
2179 | &delalloc_start, | |
d1310b2e CM |
2180 | &delalloc_end, |
2181 | 128 * 1024 * 1024); | |
771ed689 CM |
2182 | if (nr_delalloc == 0) { |
2183 | delalloc_start = delalloc_end + 1; | |
2184 | continue; | |
2185 | } | |
2186 | tree->ops->fill_delalloc(inode, page, delalloc_start, | |
2187 | delalloc_end, &page_started, | |
2188 | &nr_written); | |
d1310b2e | 2189 | delalloc_start = delalloc_end + 1; |
d1310b2e | 2190 | } |
c8b97818 | 2191 | |
771ed689 CM |
2192 | /* did the fill delalloc function already unlock and start |
2193 | * the IO? | |
2194 | */ | |
2195 | if (page_started) { | |
2196 | ret = 0; | |
2197 | goto update_nr_written; | |
2198 | } | |
c8b97818 | 2199 | } |
d1310b2e | 2200 | lock_extent(tree, start, page_end, GFP_NOFS); |
771ed689 | 2201 | |
e6dcd2dc | 2202 | unlock_start = start; |
d1310b2e | 2203 | |
247e743c | 2204 | if (tree->ops && tree->ops->writepage_start_hook) { |
c8b97818 CM |
2205 | ret = tree->ops->writepage_start_hook(page, start, |
2206 | page_end); | |
247e743c CM |
2207 | if (ret == -EAGAIN) { |
2208 | unlock_extent(tree, start, page_end, GFP_NOFS); | |
2209 | redirty_page_for_writepage(wbc, page); | |
2210 | unlock_page(page); | |
771ed689 CM |
2211 | ret = 0; |
2212 | goto update_nr_written; | |
247e743c CM |
2213 | } |
2214 | } | |
2215 | ||
771ed689 CM |
2216 | nr_written++; |
2217 | ||
d1310b2e | 2218 | end = page_end; |
d397712b CM |
2219 | if (test_range_bit(tree, start, page_end, EXTENT_DELALLOC, 0)) |
2220 | printk(KERN_ERR "btrfs delalloc bits after lock_extent\n"); | |
d1310b2e CM |
2221 | |
2222 | if (last_byte <= start) { | |
2223 | clear_extent_dirty(tree, start, page_end, GFP_NOFS); | |
e6dcd2dc CM |
2224 | unlock_extent(tree, start, page_end, GFP_NOFS); |
2225 | if (tree->ops && tree->ops->writepage_end_io_hook) | |
2226 | tree->ops->writepage_end_io_hook(page, start, | |
2227 | page_end, NULL, 1); | |
2228 | unlock_start = page_end + 1; | |
d1310b2e CM |
2229 | goto done; |
2230 | } | |
2231 | ||
2232 | set_extent_uptodate(tree, start, page_end, GFP_NOFS); | |
2233 | blocksize = inode->i_sb->s_blocksize; | |
2234 | ||
2235 | while (cur <= end) { | |
2236 | if (cur >= last_byte) { | |
2237 | clear_extent_dirty(tree, cur, page_end, GFP_NOFS); | |
e6dcd2dc CM |
2238 | unlock_extent(tree, unlock_start, page_end, GFP_NOFS); |
2239 | if (tree->ops && tree->ops->writepage_end_io_hook) | |
2240 | tree->ops->writepage_end_io_hook(page, cur, | |
2241 | page_end, NULL, 1); | |
2242 | unlock_start = page_end + 1; | |
d1310b2e CM |
2243 | break; |
2244 | } | |
7f3c74fb | 2245 | em = epd->get_extent(inode, page, pg_offset, cur, |
d1310b2e CM |
2246 | end - cur + 1, 1); |
2247 | if (IS_ERR(em) || !em) { | |
2248 | SetPageError(page); | |
2249 | break; | |
2250 | } | |
2251 | ||
2252 | extent_offset = cur - em->start; | |
2253 | BUG_ON(extent_map_end(em) <= cur); | |
2254 | BUG_ON(end < cur); | |
2255 | iosize = min(extent_map_end(em) - cur, end - cur + 1); | |
2256 | iosize = (iosize + blocksize - 1) & ~((u64)blocksize - 1); | |
2257 | sector = (em->block_start + extent_offset) >> 9; | |
2258 | bdev = em->bdev; | |
2259 | block_start = em->block_start; | |
c8b97818 | 2260 | compressed = test_bit(EXTENT_FLAG_COMPRESSED, &em->flags); |
d1310b2e CM |
2261 | free_extent_map(em); |
2262 | em = NULL; | |
2263 | ||
c8b97818 CM |
2264 | /* |
2265 | * compressed and inline extents are written through other | |
2266 | * paths in the FS | |
2267 | */ | |
2268 | if (compressed || block_start == EXTENT_MAP_HOLE || | |
d1310b2e CM |
2269 | block_start == EXTENT_MAP_INLINE) { |
2270 | clear_extent_dirty(tree, cur, | |
2271 | cur + iosize - 1, GFP_NOFS); | |
e6dcd2dc | 2272 | |
d397712b | 2273 | unlock_extent(tree, unlock_start, cur + iosize - 1, |
e6dcd2dc | 2274 | GFP_NOFS); |
7f3c74fb | 2275 | |
c8b97818 CM |
2276 | /* |
2277 | * end_io notification does not happen here for | |
2278 | * compressed extents | |
2279 | */ | |
2280 | if (!compressed && tree->ops && | |
2281 | tree->ops->writepage_end_io_hook) | |
e6dcd2dc CM |
2282 | tree->ops->writepage_end_io_hook(page, cur, |
2283 | cur + iosize - 1, | |
2284 | NULL, 1); | |
c8b97818 CM |
2285 | else if (compressed) { |
2286 | /* we don't want to end_page_writeback on | |
2287 | * a compressed extent. this happens | |
2288 | * elsewhere | |
2289 | */ | |
2290 | nr++; | |
2291 | } | |
2292 | ||
2293 | cur += iosize; | |
7f3c74fb | 2294 | pg_offset += iosize; |
e6dcd2dc | 2295 | unlock_start = cur; |
d1310b2e CM |
2296 | continue; |
2297 | } | |
d1310b2e CM |
2298 | /* leave this out until we have a page_mkwrite call */ |
2299 | if (0 && !test_range_bit(tree, cur, cur + iosize - 1, | |
2300 | EXTENT_DIRTY, 0)) { | |
2301 | cur = cur + iosize; | |
7f3c74fb | 2302 | pg_offset += iosize; |
d1310b2e CM |
2303 | continue; |
2304 | } | |
c8b97818 | 2305 | |
d1310b2e CM |
2306 | clear_extent_dirty(tree, cur, cur + iosize - 1, GFP_NOFS); |
2307 | if (tree->ops && tree->ops->writepage_io_hook) { | |
2308 | ret = tree->ops->writepage_io_hook(page, cur, | |
2309 | cur + iosize - 1); | |
2310 | } else { | |
2311 | ret = 0; | |
2312 | } | |
1259ab75 | 2313 | if (ret) { |
d1310b2e | 2314 | SetPageError(page); |
1259ab75 | 2315 | } else { |
d1310b2e | 2316 | unsigned long max_nr = end_index + 1; |
7f3c74fb | 2317 | |
d1310b2e CM |
2318 | set_range_writeback(tree, cur, cur + iosize - 1); |
2319 | if (!PageWriteback(page)) { | |
d397712b CM |
2320 | printk(KERN_ERR "btrfs warning page %lu not " |
2321 | "writeback, cur %llu end %llu\n", | |
2322 | page->index, (unsigned long long)cur, | |
d1310b2e CM |
2323 | (unsigned long long)end); |
2324 | } | |
2325 | ||
ffbd517d CM |
2326 | ret = submit_extent_page(write_flags, tree, page, |
2327 | sector, iosize, pg_offset, | |
2328 | bdev, &epd->bio, max_nr, | |
c8b97818 CM |
2329 | end_bio_extent_writepage, |
2330 | 0, 0, 0); | |
d1310b2e CM |
2331 | if (ret) |
2332 | SetPageError(page); | |
2333 | } | |
2334 | cur = cur + iosize; | |
7f3c74fb | 2335 | pg_offset += iosize; |
d1310b2e CM |
2336 | nr++; |
2337 | } | |
2338 | done: | |
2339 | if (nr == 0) { | |
2340 | /* make sure the mapping tag for page dirty gets cleared */ | |
2341 | set_page_writeback(page); | |
2342 | end_page_writeback(page); | |
2343 | } | |
e6dcd2dc CM |
2344 | if (unlock_start <= page_end) |
2345 | unlock_extent(tree, unlock_start, page_end, GFP_NOFS); | |
d1310b2e | 2346 | unlock_page(page); |
771ed689 CM |
2347 | |
2348 | update_nr_written: | |
2349 | wbc->nr_to_write -= nr_written; | |
2350 | if (wbc->range_cyclic || (wbc->nr_to_write > 0 && | |
2351 | wbc->range_start == 0 && wbc->range_end == LLONG_MAX)) | |
2352 | page->mapping->writeback_index = page->index + nr_written; | |
d1310b2e CM |
2353 | return 0; |
2354 | } | |
2355 | ||
d1310b2e | 2356 | /** |
4bef0848 | 2357 | * write_cache_pages - walk the list of dirty pages of the given address space and write all of them. |
d1310b2e CM |
2358 | * @mapping: address space structure to write |
2359 | * @wbc: subtract the number of written pages from *@wbc->nr_to_write | |
2360 | * @writepage: function called for each page | |
2361 | * @data: data passed to writepage function | |
2362 | * | |
2363 | * If a page is already under I/O, write_cache_pages() skips it, even | |
2364 | * if it's dirty. This is desirable behaviour for memory-cleaning writeback, | |
2365 | * but it is INCORRECT for data-integrity system calls such as fsync(). fsync() | |
2366 | * and msync() need to guarantee that all the data which was dirty at the time | |
2367 | * the call was made get new I/O started against them. If wbc->sync_mode is | |
2368 | * WB_SYNC_ALL then we were called for data integrity and we must wait for | |
2369 | * existing IO to complete. | |
2370 | */ | |
b2950863 | 2371 | static int extent_write_cache_pages(struct extent_io_tree *tree, |
4bef0848 CM |
2372 | struct address_space *mapping, |
2373 | struct writeback_control *wbc, | |
d2c3f4f6 CM |
2374 | writepage_t writepage, void *data, |
2375 | void (*flush_fn)(void *)) | |
d1310b2e CM |
2376 | { |
2377 | struct backing_dev_info *bdi = mapping->backing_dev_info; | |
2378 | int ret = 0; | |
2379 | int done = 0; | |
2380 | struct pagevec pvec; | |
2381 | int nr_pages; | |
2382 | pgoff_t index; | |
2383 | pgoff_t end; /* Inclusive */ | |
2384 | int scanned = 0; | |
2385 | int range_whole = 0; | |
2386 | ||
d1310b2e CM |
2387 | pagevec_init(&pvec, 0); |
2388 | if (wbc->range_cyclic) { | |
2389 | index = mapping->writeback_index; /* Start from prev offset */ | |
2390 | end = -1; | |
2391 | } else { | |
2392 | index = wbc->range_start >> PAGE_CACHE_SHIFT; | |
2393 | end = wbc->range_end >> PAGE_CACHE_SHIFT; | |
2394 | if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) | |
2395 | range_whole = 1; | |
2396 | scanned = 1; | |
2397 | } | |
2398 | retry: | |
2399 | while (!done && (index <= end) && | |
2400 | (nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, | |
d397712b CM |
2401 | PAGECACHE_TAG_DIRTY, min(end - index, |
2402 | (pgoff_t)PAGEVEC_SIZE-1) + 1))) { | |
d1310b2e CM |
2403 | unsigned i; |
2404 | ||
2405 | scanned = 1; | |
2406 | for (i = 0; i < nr_pages; i++) { | |
2407 | struct page *page = pvec.pages[i]; | |
2408 | ||
2409 | /* | |
2410 | * At this point we hold neither mapping->tree_lock nor | |
2411 | * lock on the page itself: the page may be truncated or | |
2412 | * invalidated (changing page->mapping to NULL), or even | |
2413 | * swizzled back from swapper_space to tmpfs file | |
2414 | * mapping | |
2415 | */ | |
4bef0848 CM |
2416 | if (tree->ops && tree->ops->write_cache_pages_lock_hook) |
2417 | tree->ops->write_cache_pages_lock_hook(page); | |
2418 | else | |
2419 | lock_page(page); | |
d1310b2e CM |
2420 | |
2421 | if (unlikely(page->mapping != mapping)) { | |
2422 | unlock_page(page); | |
2423 | continue; | |
2424 | } | |
2425 | ||
2426 | if (!wbc->range_cyclic && page->index > end) { | |
2427 | done = 1; | |
2428 | unlock_page(page); | |
2429 | continue; | |
2430 | } | |
2431 | ||
d2c3f4f6 | 2432 | if (wbc->sync_mode != WB_SYNC_NONE) { |
0e6bd956 CM |
2433 | if (PageWriteback(page)) |
2434 | flush_fn(data); | |
d1310b2e | 2435 | wait_on_page_writeback(page); |
d2c3f4f6 | 2436 | } |
d1310b2e CM |
2437 | |
2438 | if (PageWriteback(page) || | |
2439 | !clear_page_dirty_for_io(page)) { | |
2440 | unlock_page(page); | |
2441 | continue; | |
2442 | } | |
2443 | ||
2444 | ret = (*writepage)(page, wbc, data); | |
2445 | ||
2446 | if (unlikely(ret == AOP_WRITEPAGE_ACTIVATE)) { | |
2447 | unlock_page(page); | |
2448 | ret = 0; | |
2449 | } | |
771ed689 | 2450 | if (ret || wbc->nr_to_write <= 0) |
d1310b2e CM |
2451 | done = 1; |
2452 | if (wbc->nonblocking && bdi_write_congested(bdi)) { | |
2453 | wbc->encountered_congestion = 1; | |
2454 | done = 1; | |
2455 | } | |
2456 | } | |
2457 | pagevec_release(&pvec); | |
2458 | cond_resched(); | |
2459 | } | |
2460 | if (!scanned && !done) { | |
2461 | /* | |
2462 | * We hit the last page and there is more work to be done: wrap | |
2463 | * back to the start of the file | |
2464 | */ | |
2465 | scanned = 1; | |
2466 | index = 0; | |
2467 | goto retry; | |
2468 | } | |
d1310b2e CM |
2469 | return ret; |
2470 | } | |
d1310b2e | 2471 | |
ffbd517d | 2472 | static void flush_epd_write_bio(struct extent_page_data *epd) |
d2c3f4f6 | 2473 | { |
d2c3f4f6 | 2474 | if (epd->bio) { |
ffbd517d CM |
2475 | if (epd->sync_io) |
2476 | submit_one_bio(WRITE_SYNC, epd->bio, 0, 0); | |
2477 | else | |
2478 | submit_one_bio(WRITE, epd->bio, 0, 0); | |
d2c3f4f6 CM |
2479 | epd->bio = NULL; |
2480 | } | |
2481 | } | |
2482 | ||
ffbd517d CM |
2483 | static noinline void flush_write_bio(void *data) |
2484 | { | |
2485 | struct extent_page_data *epd = data; | |
2486 | flush_epd_write_bio(epd); | |
2487 | } | |
2488 | ||
d1310b2e CM |
2489 | int extent_write_full_page(struct extent_io_tree *tree, struct page *page, |
2490 | get_extent_t *get_extent, | |
2491 | struct writeback_control *wbc) | |
2492 | { | |
2493 | int ret; | |
2494 | struct address_space *mapping = page->mapping; | |
2495 | struct extent_page_data epd = { | |
2496 | .bio = NULL, | |
2497 | .tree = tree, | |
2498 | .get_extent = get_extent, | |
771ed689 | 2499 | .extent_locked = 0, |
ffbd517d | 2500 | .sync_io = wbc->sync_mode == WB_SYNC_ALL, |
d1310b2e CM |
2501 | }; |
2502 | struct writeback_control wbc_writepages = { | |
2503 | .bdi = wbc->bdi, | |
d313d7a3 | 2504 | .sync_mode = wbc->sync_mode, |
d1310b2e CM |
2505 | .older_than_this = NULL, |
2506 | .nr_to_write = 64, | |
2507 | .range_start = page_offset(page) + PAGE_CACHE_SIZE, | |
2508 | .range_end = (loff_t)-1, | |
2509 | }; | |
2510 | ||
d1310b2e CM |
2511 | ret = __extent_writepage(page, wbc, &epd); |
2512 | ||
4bef0848 | 2513 | extent_write_cache_pages(tree, mapping, &wbc_writepages, |
d2c3f4f6 | 2514 | __extent_writepage, &epd, flush_write_bio); |
ffbd517d | 2515 | flush_epd_write_bio(&epd); |
d1310b2e CM |
2516 | return ret; |
2517 | } | |
d1310b2e | 2518 | |
771ed689 CM |
2519 | int extent_write_locked_range(struct extent_io_tree *tree, struct inode *inode, |
2520 | u64 start, u64 end, get_extent_t *get_extent, | |
2521 | int mode) | |
2522 | { | |
2523 | int ret = 0; | |
2524 | struct address_space *mapping = inode->i_mapping; | |
2525 | struct page *page; | |
2526 | unsigned long nr_pages = (end - start + PAGE_CACHE_SIZE) >> | |
2527 | PAGE_CACHE_SHIFT; | |
2528 | ||
2529 | struct extent_page_data epd = { | |
2530 | .bio = NULL, | |
2531 | .tree = tree, | |
2532 | .get_extent = get_extent, | |
2533 | .extent_locked = 1, | |
ffbd517d | 2534 | .sync_io = mode == WB_SYNC_ALL, |
771ed689 CM |
2535 | }; |
2536 | struct writeback_control wbc_writepages = { | |
2537 | .bdi = inode->i_mapping->backing_dev_info, | |
2538 | .sync_mode = mode, | |
2539 | .older_than_this = NULL, | |
2540 | .nr_to_write = nr_pages * 2, | |
2541 | .range_start = start, | |
2542 | .range_end = end + 1, | |
2543 | }; | |
2544 | ||
d397712b | 2545 | while (start <= end) { |
771ed689 CM |
2546 | page = find_get_page(mapping, start >> PAGE_CACHE_SHIFT); |
2547 | if (clear_page_dirty_for_io(page)) | |
2548 | ret = __extent_writepage(page, &wbc_writepages, &epd); | |
2549 | else { | |
2550 | if (tree->ops && tree->ops->writepage_end_io_hook) | |
2551 | tree->ops->writepage_end_io_hook(page, start, | |
2552 | start + PAGE_CACHE_SIZE - 1, | |
2553 | NULL, 1); | |
2554 | unlock_page(page); | |
2555 | } | |
2556 | page_cache_release(page); | |
2557 | start += PAGE_CACHE_SIZE; | |
2558 | } | |
2559 | ||
ffbd517d | 2560 | flush_epd_write_bio(&epd); |
771ed689 CM |
2561 | return ret; |
2562 | } | |
d1310b2e CM |
2563 | |
2564 | int extent_writepages(struct extent_io_tree *tree, | |
2565 | struct address_space *mapping, | |
2566 | get_extent_t *get_extent, | |
2567 | struct writeback_control *wbc) | |
2568 | { | |
2569 | int ret = 0; | |
2570 | struct extent_page_data epd = { | |
2571 | .bio = NULL, | |
2572 | .tree = tree, | |
2573 | .get_extent = get_extent, | |
771ed689 | 2574 | .extent_locked = 0, |
ffbd517d | 2575 | .sync_io = wbc->sync_mode == WB_SYNC_ALL, |
d1310b2e CM |
2576 | }; |
2577 | ||
4bef0848 | 2578 | ret = extent_write_cache_pages(tree, mapping, wbc, |
d2c3f4f6 CM |
2579 | __extent_writepage, &epd, |
2580 | flush_write_bio); | |
ffbd517d | 2581 | flush_epd_write_bio(&epd); |
d1310b2e CM |
2582 | return ret; |
2583 | } | |
d1310b2e CM |
2584 | |
2585 | int extent_readpages(struct extent_io_tree *tree, | |
2586 | struct address_space *mapping, | |
2587 | struct list_head *pages, unsigned nr_pages, | |
2588 | get_extent_t get_extent) | |
2589 | { | |
2590 | struct bio *bio = NULL; | |
2591 | unsigned page_idx; | |
2592 | struct pagevec pvec; | |
c8b97818 | 2593 | unsigned long bio_flags = 0; |
d1310b2e CM |
2594 | |
2595 | pagevec_init(&pvec, 0); | |
2596 | for (page_idx = 0; page_idx < nr_pages; page_idx++) { | |
2597 | struct page *page = list_entry(pages->prev, struct page, lru); | |
2598 | ||
2599 | prefetchw(&page->flags); | |
2600 | list_del(&page->lru); | |
2601 | /* | |
2602 | * what we want to do here is call add_to_page_cache_lru, | |
2603 | * but that isn't exported, so we reproduce it here | |
2604 | */ | |
2605 | if (!add_to_page_cache(page, mapping, | |
2606 | page->index, GFP_KERNEL)) { | |
2607 | ||
2608 | /* open coding of lru_cache_add, also not exported */ | |
2609 | page_cache_get(page); | |
2610 | if (!pagevec_add(&pvec, page)) | |
15916de8 | 2611 | __pagevec_lru_add_file(&pvec); |
f188591e | 2612 | __extent_read_full_page(tree, page, get_extent, |
c8b97818 | 2613 | &bio, 0, &bio_flags); |
d1310b2e CM |
2614 | } |
2615 | page_cache_release(page); | |
2616 | } | |
2617 | if (pagevec_count(&pvec)) | |
15916de8 | 2618 | __pagevec_lru_add_file(&pvec); |
d1310b2e CM |
2619 | BUG_ON(!list_empty(pages)); |
2620 | if (bio) | |
c8b97818 | 2621 | submit_one_bio(READ, bio, 0, bio_flags); |
d1310b2e CM |
2622 | return 0; |
2623 | } | |
d1310b2e CM |
2624 | |
2625 | /* | |
2626 | * basic invalidatepage code, this waits on any locked or writeback | |
2627 | * ranges corresponding to the page, and then deletes any extent state | |
2628 | * records from the tree | |
2629 | */ | |
2630 | int extent_invalidatepage(struct extent_io_tree *tree, | |
2631 | struct page *page, unsigned long offset) | |
2632 | { | |
2633 | u64 start = ((u64)page->index << PAGE_CACHE_SHIFT); | |
2634 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
2635 | size_t blocksize = page->mapping->host->i_sb->s_blocksize; | |
2636 | ||
d397712b | 2637 | start += (offset + blocksize - 1) & ~(blocksize - 1); |
d1310b2e CM |
2638 | if (start > end) |
2639 | return 0; | |
2640 | ||
2641 | lock_extent(tree, start, end, GFP_NOFS); | |
2642 | wait_on_extent_writeback(tree, start, end); | |
2643 | clear_extent_bit(tree, start, end, | |
2644 | EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC, | |
2645 | 1, 1, GFP_NOFS); | |
2646 | return 0; | |
2647 | } | |
d1310b2e CM |
2648 | |
2649 | /* | |
2650 | * simple commit_write call, set_range_dirty is used to mark both | |
2651 | * the pages and the extent records as dirty | |
2652 | */ | |
2653 | int extent_commit_write(struct extent_io_tree *tree, | |
2654 | struct inode *inode, struct page *page, | |
2655 | unsigned from, unsigned to) | |
2656 | { | |
2657 | loff_t pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to; | |
2658 | ||
2659 | set_page_extent_mapped(page); | |
2660 | set_page_dirty(page); | |
2661 | ||
2662 | if (pos > inode->i_size) { | |
2663 | i_size_write(inode, pos); | |
2664 | mark_inode_dirty(inode); | |
2665 | } | |
2666 | return 0; | |
2667 | } | |
d1310b2e CM |
2668 | |
2669 | int extent_prepare_write(struct extent_io_tree *tree, | |
2670 | struct inode *inode, struct page *page, | |
2671 | unsigned from, unsigned to, get_extent_t *get_extent) | |
2672 | { | |
2673 | u64 page_start = (u64)page->index << PAGE_CACHE_SHIFT; | |
2674 | u64 page_end = page_start + PAGE_CACHE_SIZE - 1; | |
2675 | u64 block_start; | |
2676 | u64 orig_block_start; | |
2677 | u64 block_end; | |
2678 | u64 cur_end; | |
2679 | struct extent_map *em; | |
2680 | unsigned blocksize = 1 << inode->i_blkbits; | |
2681 | size_t page_offset = 0; | |
2682 | size_t block_off_start; | |
2683 | size_t block_off_end; | |
2684 | int err = 0; | |
2685 | int iocount = 0; | |
2686 | int ret = 0; | |
2687 | int isnew; | |
2688 | ||
2689 | set_page_extent_mapped(page); | |
2690 | ||
2691 | block_start = (page_start + from) & ~((u64)blocksize - 1); | |
2692 | block_end = (page_start + to - 1) | (blocksize - 1); | |
2693 | orig_block_start = block_start; | |
2694 | ||
2695 | lock_extent(tree, page_start, page_end, GFP_NOFS); | |
d397712b | 2696 | while (block_start <= block_end) { |
d1310b2e CM |
2697 | em = get_extent(inode, page, page_offset, block_start, |
2698 | block_end - block_start + 1, 1); | |
d397712b | 2699 | if (IS_ERR(em) || !em) |
d1310b2e | 2700 | goto err; |
d397712b | 2701 | |
d1310b2e CM |
2702 | cur_end = min(block_end, extent_map_end(em) - 1); |
2703 | block_off_start = block_start & (PAGE_CACHE_SIZE - 1); | |
2704 | block_off_end = block_off_start + blocksize; | |
2705 | isnew = clear_extent_new(tree, block_start, cur_end, GFP_NOFS); | |
2706 | ||
2707 | if (!PageUptodate(page) && isnew && | |
2708 | (block_off_end > to || block_off_start < from)) { | |
2709 | void *kaddr; | |
2710 | ||
2711 | kaddr = kmap_atomic(page, KM_USER0); | |
2712 | if (block_off_end > to) | |
2713 | memset(kaddr + to, 0, block_off_end - to); | |
2714 | if (block_off_start < from) | |
2715 | memset(kaddr + block_off_start, 0, | |
2716 | from - block_off_start); | |
2717 | flush_dcache_page(page); | |
2718 | kunmap_atomic(kaddr, KM_USER0); | |
2719 | } | |
2720 | if ((em->block_start != EXTENT_MAP_HOLE && | |
2721 | em->block_start != EXTENT_MAP_INLINE) && | |
2722 | !isnew && !PageUptodate(page) && | |
2723 | (block_off_end > to || block_off_start < from) && | |
2724 | !test_range_bit(tree, block_start, cur_end, | |
2725 | EXTENT_UPTODATE, 1)) { | |
2726 | u64 sector; | |
2727 | u64 extent_offset = block_start - em->start; | |
2728 | size_t iosize; | |
2729 | sector = (em->block_start + extent_offset) >> 9; | |
2730 | iosize = (cur_end - block_start + blocksize) & | |
2731 | ~((u64)blocksize - 1); | |
2732 | /* | |
2733 | * we've already got the extent locked, but we | |
2734 | * need to split the state such that our end_bio | |
2735 | * handler can clear the lock. | |
2736 | */ | |
2737 | set_extent_bit(tree, block_start, | |
2738 | block_start + iosize - 1, | |
2739 | EXTENT_LOCKED, 0, NULL, GFP_NOFS); | |
2740 | ret = submit_extent_page(READ, tree, page, | |
2741 | sector, iosize, page_offset, em->bdev, | |
2742 | NULL, 1, | |
c8b97818 CM |
2743 | end_bio_extent_preparewrite, 0, |
2744 | 0, 0); | |
d1310b2e CM |
2745 | iocount++; |
2746 | block_start = block_start + iosize; | |
2747 | } else { | |
2748 | set_extent_uptodate(tree, block_start, cur_end, | |
2749 | GFP_NOFS); | |
2750 | unlock_extent(tree, block_start, cur_end, GFP_NOFS); | |
2751 | block_start = cur_end + 1; | |
2752 | } | |
2753 | page_offset = block_start & (PAGE_CACHE_SIZE - 1); | |
2754 | free_extent_map(em); | |
2755 | } | |
2756 | if (iocount) { | |
2757 | wait_extent_bit(tree, orig_block_start, | |
2758 | block_end, EXTENT_LOCKED); | |
2759 | } | |
2760 | check_page_uptodate(tree, page); | |
2761 | err: | |
2762 | /* FIXME, zero out newly allocated blocks on error */ | |
2763 | return err; | |
2764 | } | |
d1310b2e | 2765 | |
7b13b7b1 CM |
2766 | /* |
2767 | * a helper for releasepage, this tests for areas of the page that | |
2768 | * are locked or under IO and drops the related state bits if it is safe | |
2769 | * to drop the page. | |
2770 | */ | |
2771 | int try_release_extent_state(struct extent_map_tree *map, | |
2772 | struct extent_io_tree *tree, struct page *page, | |
2773 | gfp_t mask) | |
2774 | { | |
2775 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
2776 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
2777 | int ret = 1; | |
2778 | ||
211f90e6 CM |
2779 | if (test_range_bit(tree, start, end, |
2780 | EXTENT_IOBITS | EXTENT_ORDERED, 0)) | |
7b13b7b1 CM |
2781 | ret = 0; |
2782 | else { | |
2783 | if ((mask & GFP_NOFS) == GFP_NOFS) | |
2784 | mask = GFP_NOFS; | |
2785 | clear_extent_bit(tree, start, end, EXTENT_UPTODATE, | |
2786 | 1, 1, mask); | |
2787 | } | |
2788 | return ret; | |
2789 | } | |
7b13b7b1 | 2790 | |
d1310b2e CM |
2791 | /* |
2792 | * a helper for releasepage. As long as there are no locked extents | |
2793 | * in the range corresponding to the page, both state records and extent | |
2794 | * map records are removed | |
2795 | */ | |
2796 | int try_release_extent_mapping(struct extent_map_tree *map, | |
70dec807 CM |
2797 | struct extent_io_tree *tree, struct page *page, |
2798 | gfp_t mask) | |
d1310b2e CM |
2799 | { |
2800 | struct extent_map *em; | |
2801 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
2802 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
7b13b7b1 | 2803 | |
70dec807 CM |
2804 | if ((mask & __GFP_WAIT) && |
2805 | page->mapping->host->i_size > 16 * 1024 * 1024) { | |
39b5637f | 2806 | u64 len; |
70dec807 | 2807 | while (start <= end) { |
39b5637f | 2808 | len = end - start + 1; |
70dec807 | 2809 | spin_lock(&map->lock); |
39b5637f | 2810 | em = lookup_extent_mapping(map, start, len); |
70dec807 CM |
2811 | if (!em || IS_ERR(em)) { |
2812 | spin_unlock(&map->lock); | |
2813 | break; | |
2814 | } | |
7f3c74fb CM |
2815 | if (test_bit(EXTENT_FLAG_PINNED, &em->flags) || |
2816 | em->start != start) { | |
70dec807 CM |
2817 | spin_unlock(&map->lock); |
2818 | free_extent_map(em); | |
2819 | break; | |
2820 | } | |
2821 | if (!test_range_bit(tree, em->start, | |
2822 | extent_map_end(em) - 1, | |
c8b97818 CM |
2823 | EXTENT_LOCKED | EXTENT_WRITEBACK | |
2824 | EXTENT_ORDERED, | |
2825 | 0)) { | |
70dec807 CM |
2826 | remove_extent_mapping(map, em); |
2827 | /* once for the rb tree */ | |
2828 | free_extent_map(em); | |
2829 | } | |
2830 | start = extent_map_end(em); | |
d1310b2e | 2831 | spin_unlock(&map->lock); |
70dec807 CM |
2832 | |
2833 | /* once for us */ | |
d1310b2e CM |
2834 | free_extent_map(em); |
2835 | } | |
d1310b2e | 2836 | } |
7b13b7b1 | 2837 | return try_release_extent_state(map, tree, page, mask); |
d1310b2e | 2838 | } |
d1310b2e CM |
2839 | |
2840 | sector_t extent_bmap(struct address_space *mapping, sector_t iblock, | |
2841 | get_extent_t *get_extent) | |
2842 | { | |
2843 | struct inode *inode = mapping->host; | |
2844 | u64 start = iblock << inode->i_blkbits; | |
2845 | sector_t sector = 0; | |
d899e052 | 2846 | size_t blksize = (1 << inode->i_blkbits); |
d1310b2e CM |
2847 | struct extent_map *em; |
2848 | ||
d899e052 YZ |
2849 | lock_extent(&BTRFS_I(inode)->io_tree, start, start + blksize - 1, |
2850 | GFP_NOFS); | |
2851 | em = get_extent(inode, NULL, 0, start, blksize, 0); | |
2852 | unlock_extent(&BTRFS_I(inode)->io_tree, start, start + blksize - 1, | |
2853 | GFP_NOFS); | |
d1310b2e CM |
2854 | if (!em || IS_ERR(em)) |
2855 | return 0; | |
2856 | ||
d899e052 | 2857 | if (em->block_start > EXTENT_MAP_LAST_BYTE) |
d1310b2e CM |
2858 | goto out; |
2859 | ||
2860 | sector = (em->block_start + start - em->start) >> inode->i_blkbits; | |
d1310b2e CM |
2861 | out: |
2862 | free_extent_map(em); | |
2863 | return sector; | |
2864 | } | |
2865 | ||
1506fcc8 YS |
2866 | int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, |
2867 | __u64 start, __u64 len, get_extent_t *get_extent) | |
2868 | { | |
2869 | int ret; | |
2870 | u64 off = start; | |
2871 | u64 max = start + len; | |
2872 | u32 flags = 0; | |
2873 | u64 disko = 0; | |
2874 | struct extent_map *em = NULL; | |
2875 | int end = 0; | |
2876 | u64 em_start = 0, em_len = 0; | |
2877 | unsigned long emflags; | |
2878 | ret = 0; | |
2879 | ||
2880 | if (len == 0) | |
2881 | return -EINVAL; | |
2882 | ||
2883 | lock_extent(&BTRFS_I(inode)->io_tree, start, start + len, | |
2884 | GFP_NOFS); | |
2885 | em = get_extent(inode, NULL, 0, off, max - off, 0); | |
2886 | if (!em) | |
2887 | goto out; | |
2888 | if (IS_ERR(em)) { | |
2889 | ret = PTR_ERR(em); | |
2890 | goto out; | |
2891 | } | |
2892 | while (!end) { | |
2893 | off = em->start + em->len; | |
2894 | if (off >= max) | |
2895 | end = 1; | |
2896 | ||
2897 | em_start = em->start; | |
2898 | em_len = em->len; | |
2899 | ||
2900 | disko = 0; | |
2901 | flags = 0; | |
2902 | ||
93dbfad7 | 2903 | if (em->block_start == EXTENT_MAP_LAST_BYTE) { |
1506fcc8 YS |
2904 | end = 1; |
2905 | flags |= FIEMAP_EXTENT_LAST; | |
93dbfad7 | 2906 | } else if (em->block_start == EXTENT_MAP_HOLE) { |
1506fcc8 | 2907 | flags |= FIEMAP_EXTENT_UNWRITTEN; |
93dbfad7 | 2908 | } else if (em->block_start == EXTENT_MAP_INLINE) { |
1506fcc8 YS |
2909 | flags |= (FIEMAP_EXTENT_DATA_INLINE | |
2910 | FIEMAP_EXTENT_NOT_ALIGNED); | |
93dbfad7 | 2911 | } else if (em->block_start == EXTENT_MAP_DELALLOC) { |
1506fcc8 YS |
2912 | flags |= (FIEMAP_EXTENT_DELALLOC | |
2913 | FIEMAP_EXTENT_UNKNOWN); | |
93dbfad7 | 2914 | } else { |
1506fcc8 | 2915 | disko = em->block_start; |
1506fcc8 YS |
2916 | } |
2917 | if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) | |
2918 | flags |= FIEMAP_EXTENT_ENCODED; | |
2919 | ||
2920 | emflags = em->flags; | |
2921 | free_extent_map(em); | |
2922 | em = NULL; | |
2923 | ||
2924 | if (!end) { | |
2925 | em = get_extent(inode, NULL, 0, off, max - off, 0); | |
2926 | if (!em) | |
2927 | goto out; | |
2928 | if (IS_ERR(em)) { | |
2929 | ret = PTR_ERR(em); | |
2930 | goto out; | |
2931 | } | |
2932 | emflags = em->flags; | |
2933 | } | |
2934 | if (test_bit(EXTENT_FLAG_VACANCY, &emflags)) { | |
2935 | flags |= FIEMAP_EXTENT_LAST; | |
2936 | end = 1; | |
2937 | } | |
2938 | ||
2939 | ret = fiemap_fill_next_extent(fieinfo, em_start, disko, | |
2940 | em_len, flags); | |
2941 | if (ret) | |
2942 | goto out_free; | |
2943 | } | |
2944 | out_free: | |
2945 | free_extent_map(em); | |
2946 | out: | |
2947 | unlock_extent(&BTRFS_I(inode)->io_tree, start, start + len, | |
2948 | GFP_NOFS); | |
2949 | return ret; | |
2950 | } | |
2951 | ||
d1310b2e CM |
2952 | static inline struct page *extent_buffer_page(struct extent_buffer *eb, |
2953 | unsigned long i) | |
2954 | { | |
2955 | struct page *p; | |
2956 | struct address_space *mapping; | |
2957 | ||
2958 | if (i == 0) | |
2959 | return eb->first_page; | |
2960 | i += eb->start >> PAGE_CACHE_SHIFT; | |
2961 | mapping = eb->first_page->mapping; | |
33958dc6 CM |
2962 | if (!mapping) |
2963 | return NULL; | |
0ee0fda0 SW |
2964 | |
2965 | /* | |
2966 | * extent_buffer_page is only called after pinning the page | |
2967 | * by increasing the reference count. So we know the page must | |
2968 | * be in the radix tree. | |
2969 | */ | |
0ee0fda0 | 2970 | rcu_read_lock(); |
d1310b2e | 2971 | p = radix_tree_lookup(&mapping->page_tree, i); |
0ee0fda0 | 2972 | rcu_read_unlock(); |
2b1f55b0 | 2973 | |
d1310b2e CM |
2974 | return p; |
2975 | } | |
2976 | ||
6af118ce | 2977 | static inline unsigned long num_extent_pages(u64 start, u64 len) |
728131d8 | 2978 | { |
6af118ce CM |
2979 | return ((start + len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT) - |
2980 | (start >> PAGE_CACHE_SHIFT); | |
728131d8 CM |
2981 | } |
2982 | ||
d1310b2e CM |
2983 | static struct extent_buffer *__alloc_extent_buffer(struct extent_io_tree *tree, |
2984 | u64 start, | |
2985 | unsigned long len, | |
2986 | gfp_t mask) | |
2987 | { | |
2988 | struct extent_buffer *eb = NULL; | |
3935127c | 2989 | #if LEAK_DEBUG |
2d2ae547 | 2990 | unsigned long flags; |
4bef0848 | 2991 | #endif |
d1310b2e | 2992 | |
d1310b2e | 2993 | eb = kmem_cache_zalloc(extent_buffer_cache, mask); |
d1310b2e CM |
2994 | eb->start = start; |
2995 | eb->len = len; | |
b4ce94de CM |
2996 | spin_lock_init(&eb->lock); |
2997 | init_waitqueue_head(&eb->lock_wq); | |
2998 | ||
3935127c | 2999 | #if LEAK_DEBUG |
2d2ae547 CM |
3000 | spin_lock_irqsave(&leak_lock, flags); |
3001 | list_add(&eb->leak_list, &buffers); | |
3002 | spin_unlock_irqrestore(&leak_lock, flags); | |
4bef0848 | 3003 | #endif |
d1310b2e CM |
3004 | atomic_set(&eb->refs, 1); |
3005 | ||
3006 | return eb; | |
3007 | } | |
3008 | ||
3009 | static void __free_extent_buffer(struct extent_buffer *eb) | |
3010 | { | |
3935127c | 3011 | #if LEAK_DEBUG |
2d2ae547 CM |
3012 | unsigned long flags; |
3013 | spin_lock_irqsave(&leak_lock, flags); | |
3014 | list_del(&eb->leak_list); | |
3015 | spin_unlock_irqrestore(&leak_lock, flags); | |
4bef0848 | 3016 | #endif |
d1310b2e CM |
3017 | kmem_cache_free(extent_buffer_cache, eb); |
3018 | } | |
3019 | ||
3020 | struct extent_buffer *alloc_extent_buffer(struct extent_io_tree *tree, | |
3021 | u64 start, unsigned long len, | |
3022 | struct page *page0, | |
3023 | gfp_t mask) | |
3024 | { | |
3025 | unsigned long num_pages = num_extent_pages(start, len); | |
3026 | unsigned long i; | |
3027 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
3028 | struct extent_buffer *eb; | |
6af118ce | 3029 | struct extent_buffer *exists = NULL; |
d1310b2e CM |
3030 | struct page *p; |
3031 | struct address_space *mapping = tree->mapping; | |
3032 | int uptodate = 1; | |
3033 | ||
6af118ce CM |
3034 | spin_lock(&tree->buffer_lock); |
3035 | eb = buffer_search(tree, start); | |
3036 | if (eb) { | |
3037 | atomic_inc(&eb->refs); | |
3038 | spin_unlock(&tree->buffer_lock); | |
0f9dd46c | 3039 | mark_page_accessed(eb->first_page); |
6af118ce CM |
3040 | return eb; |
3041 | } | |
3042 | spin_unlock(&tree->buffer_lock); | |
3043 | ||
d1310b2e | 3044 | eb = __alloc_extent_buffer(tree, start, len, mask); |
2b114d1d | 3045 | if (!eb) |
d1310b2e CM |
3046 | return NULL; |
3047 | ||
d1310b2e CM |
3048 | if (page0) { |
3049 | eb->first_page = page0; | |
3050 | i = 1; | |
3051 | index++; | |
3052 | page_cache_get(page0); | |
3053 | mark_page_accessed(page0); | |
3054 | set_page_extent_mapped(page0); | |
d1310b2e | 3055 | set_page_extent_head(page0, len); |
f188591e | 3056 | uptodate = PageUptodate(page0); |
d1310b2e CM |
3057 | } else { |
3058 | i = 0; | |
3059 | } | |
3060 | for (; i < num_pages; i++, index++) { | |
3061 | p = find_or_create_page(mapping, index, mask | __GFP_HIGHMEM); | |
3062 | if (!p) { | |
3063 | WARN_ON(1); | |
6af118ce | 3064 | goto free_eb; |
d1310b2e CM |
3065 | } |
3066 | set_page_extent_mapped(p); | |
3067 | mark_page_accessed(p); | |
3068 | if (i == 0) { | |
3069 | eb->first_page = p; | |
3070 | set_page_extent_head(p, len); | |
3071 | } else { | |
3072 | set_page_private(p, EXTENT_PAGE_PRIVATE); | |
3073 | } | |
3074 | if (!PageUptodate(p)) | |
3075 | uptodate = 0; | |
3076 | unlock_page(p); | |
3077 | } | |
3078 | if (uptodate) | |
b4ce94de | 3079 | set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags); |
d1310b2e | 3080 | |
6af118ce CM |
3081 | spin_lock(&tree->buffer_lock); |
3082 | exists = buffer_tree_insert(tree, start, &eb->rb_node); | |
3083 | if (exists) { | |
3084 | /* add one reference for the caller */ | |
3085 | atomic_inc(&exists->refs); | |
3086 | spin_unlock(&tree->buffer_lock); | |
3087 | goto free_eb; | |
3088 | } | |
3089 | spin_unlock(&tree->buffer_lock); | |
3090 | ||
3091 | /* add one reference for the tree */ | |
3092 | atomic_inc(&eb->refs); | |
d1310b2e CM |
3093 | return eb; |
3094 | ||
6af118ce | 3095 | free_eb: |
d1310b2e | 3096 | if (!atomic_dec_and_test(&eb->refs)) |
6af118ce CM |
3097 | return exists; |
3098 | for (index = 1; index < i; index++) | |
d1310b2e | 3099 | page_cache_release(extent_buffer_page(eb, index)); |
6af118ce | 3100 | page_cache_release(extent_buffer_page(eb, 0)); |
d1310b2e | 3101 | __free_extent_buffer(eb); |
6af118ce | 3102 | return exists; |
d1310b2e | 3103 | } |
d1310b2e CM |
3104 | |
3105 | struct extent_buffer *find_extent_buffer(struct extent_io_tree *tree, | |
3106 | u64 start, unsigned long len, | |
3107 | gfp_t mask) | |
3108 | { | |
d1310b2e | 3109 | struct extent_buffer *eb; |
d1310b2e | 3110 | |
6af118ce CM |
3111 | spin_lock(&tree->buffer_lock); |
3112 | eb = buffer_search(tree, start); | |
3113 | if (eb) | |
3114 | atomic_inc(&eb->refs); | |
3115 | spin_unlock(&tree->buffer_lock); | |
d1310b2e | 3116 | |
0f9dd46c JB |
3117 | if (eb) |
3118 | mark_page_accessed(eb->first_page); | |
3119 | ||
d1310b2e | 3120 | return eb; |
d1310b2e | 3121 | } |
d1310b2e CM |
3122 | |
3123 | void free_extent_buffer(struct extent_buffer *eb) | |
3124 | { | |
d1310b2e CM |
3125 | if (!eb) |
3126 | return; | |
3127 | ||
3128 | if (!atomic_dec_and_test(&eb->refs)) | |
3129 | return; | |
3130 | ||
6af118ce | 3131 | WARN_ON(1); |
d1310b2e | 3132 | } |
d1310b2e CM |
3133 | |
3134 | int clear_extent_buffer_dirty(struct extent_io_tree *tree, | |
3135 | struct extent_buffer *eb) | |
3136 | { | |
d1310b2e CM |
3137 | unsigned long i; |
3138 | unsigned long num_pages; | |
3139 | struct page *page; | |
3140 | ||
d1310b2e CM |
3141 | num_pages = num_extent_pages(eb->start, eb->len); |
3142 | ||
3143 | for (i = 0; i < num_pages; i++) { | |
3144 | page = extent_buffer_page(eb, i); | |
b9473439 | 3145 | if (!PageDirty(page)) |
d2c3f4f6 CM |
3146 | continue; |
3147 | ||
a61e6f29 | 3148 | lock_page(page); |
d1310b2e CM |
3149 | if (i == 0) |
3150 | set_page_extent_head(page, eb->len); | |
3151 | else | |
3152 | set_page_private(page, EXTENT_PAGE_PRIVATE); | |
3153 | ||
d1310b2e | 3154 | clear_page_dirty_for_io(page); |
0ee0fda0 | 3155 | spin_lock_irq(&page->mapping->tree_lock); |
d1310b2e CM |
3156 | if (!PageDirty(page)) { |
3157 | radix_tree_tag_clear(&page->mapping->page_tree, | |
3158 | page_index(page), | |
3159 | PAGECACHE_TAG_DIRTY); | |
3160 | } | |
0ee0fda0 | 3161 | spin_unlock_irq(&page->mapping->tree_lock); |
a61e6f29 | 3162 | unlock_page(page); |
d1310b2e CM |
3163 | } |
3164 | return 0; | |
3165 | } | |
d1310b2e CM |
3166 | |
3167 | int wait_on_extent_buffer_writeback(struct extent_io_tree *tree, | |
3168 | struct extent_buffer *eb) | |
3169 | { | |
3170 | return wait_on_extent_writeback(tree, eb->start, | |
3171 | eb->start + eb->len - 1); | |
3172 | } | |
d1310b2e CM |
3173 | |
3174 | int set_extent_buffer_dirty(struct extent_io_tree *tree, | |
3175 | struct extent_buffer *eb) | |
3176 | { | |
3177 | unsigned long i; | |
3178 | unsigned long num_pages; | |
b9473439 | 3179 | int was_dirty = 0; |
d1310b2e | 3180 | |
b9473439 | 3181 | was_dirty = test_and_set_bit(EXTENT_BUFFER_DIRTY, &eb->bflags); |
d1310b2e | 3182 | num_pages = num_extent_pages(eb->start, eb->len); |
b9473439 | 3183 | for (i = 0; i < num_pages; i++) |
d1310b2e | 3184 | __set_page_dirty_nobuffers(extent_buffer_page(eb, i)); |
b9473439 | 3185 | return was_dirty; |
d1310b2e | 3186 | } |
d1310b2e | 3187 | |
1259ab75 CM |
3188 | int clear_extent_buffer_uptodate(struct extent_io_tree *tree, |
3189 | struct extent_buffer *eb) | |
3190 | { | |
3191 | unsigned long i; | |
3192 | struct page *page; | |
3193 | unsigned long num_pages; | |
3194 | ||
3195 | num_pages = num_extent_pages(eb->start, eb->len); | |
b4ce94de | 3196 | clear_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags); |
1259ab75 CM |
3197 | |
3198 | clear_extent_uptodate(tree, eb->start, eb->start + eb->len - 1, | |
3199 | GFP_NOFS); | |
3200 | for (i = 0; i < num_pages; i++) { | |
3201 | page = extent_buffer_page(eb, i); | |
33958dc6 CM |
3202 | if (page) |
3203 | ClearPageUptodate(page); | |
1259ab75 CM |
3204 | } |
3205 | return 0; | |
3206 | } | |
3207 | ||
d1310b2e CM |
3208 | int set_extent_buffer_uptodate(struct extent_io_tree *tree, |
3209 | struct extent_buffer *eb) | |
3210 | { | |
3211 | unsigned long i; | |
3212 | struct page *page; | |
3213 | unsigned long num_pages; | |
3214 | ||
3215 | num_pages = num_extent_pages(eb->start, eb->len); | |
3216 | ||
3217 | set_extent_uptodate(tree, eb->start, eb->start + eb->len - 1, | |
3218 | GFP_NOFS); | |
3219 | for (i = 0; i < num_pages; i++) { | |
3220 | page = extent_buffer_page(eb, i); | |
3221 | if ((i == 0 && (eb->start & (PAGE_CACHE_SIZE - 1))) || | |
3222 | ((i == num_pages - 1) && | |
3223 | ((eb->start + eb->len) & (PAGE_CACHE_SIZE - 1)))) { | |
3224 | check_page_uptodate(tree, page); | |
3225 | continue; | |
3226 | } | |
3227 | SetPageUptodate(page); | |
3228 | } | |
3229 | return 0; | |
3230 | } | |
d1310b2e | 3231 | |
ce9adaa5 CM |
3232 | int extent_range_uptodate(struct extent_io_tree *tree, |
3233 | u64 start, u64 end) | |
3234 | { | |
3235 | struct page *page; | |
3236 | int ret; | |
3237 | int pg_uptodate = 1; | |
3238 | int uptodate; | |
3239 | unsigned long index; | |
3240 | ||
3241 | ret = test_range_bit(tree, start, end, EXTENT_UPTODATE, 1); | |
3242 | if (ret) | |
3243 | return 1; | |
d397712b | 3244 | while (start <= end) { |
ce9adaa5 CM |
3245 | index = start >> PAGE_CACHE_SHIFT; |
3246 | page = find_get_page(tree->mapping, index); | |
3247 | uptodate = PageUptodate(page); | |
3248 | page_cache_release(page); | |
3249 | if (!uptodate) { | |
3250 | pg_uptodate = 0; | |
3251 | break; | |
3252 | } | |
3253 | start += PAGE_CACHE_SIZE; | |
3254 | } | |
3255 | return pg_uptodate; | |
3256 | } | |
3257 | ||
d1310b2e | 3258 | int extent_buffer_uptodate(struct extent_io_tree *tree, |
ce9adaa5 | 3259 | struct extent_buffer *eb) |
d1310b2e | 3260 | { |
728131d8 | 3261 | int ret = 0; |
ce9adaa5 CM |
3262 | unsigned long num_pages; |
3263 | unsigned long i; | |
728131d8 CM |
3264 | struct page *page; |
3265 | int pg_uptodate = 1; | |
3266 | ||
b4ce94de | 3267 | if (test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags)) |
4235298e | 3268 | return 1; |
728131d8 | 3269 | |
4235298e | 3270 | ret = test_range_bit(tree, eb->start, eb->start + eb->len - 1, |
d1310b2e | 3271 | EXTENT_UPTODATE, 1); |
4235298e CM |
3272 | if (ret) |
3273 | return ret; | |
728131d8 CM |
3274 | |
3275 | num_pages = num_extent_pages(eb->start, eb->len); | |
3276 | for (i = 0; i < num_pages; i++) { | |
3277 | page = extent_buffer_page(eb, i); | |
3278 | if (!PageUptodate(page)) { | |
3279 | pg_uptodate = 0; | |
3280 | break; | |
3281 | } | |
3282 | } | |
4235298e | 3283 | return pg_uptodate; |
d1310b2e | 3284 | } |
d1310b2e CM |
3285 | |
3286 | int read_extent_buffer_pages(struct extent_io_tree *tree, | |
3287 | struct extent_buffer *eb, | |
a86c12c7 | 3288 | u64 start, int wait, |
f188591e | 3289 | get_extent_t *get_extent, int mirror_num) |
d1310b2e CM |
3290 | { |
3291 | unsigned long i; | |
3292 | unsigned long start_i; | |
3293 | struct page *page; | |
3294 | int err; | |
3295 | int ret = 0; | |
ce9adaa5 CM |
3296 | int locked_pages = 0; |
3297 | int all_uptodate = 1; | |
3298 | int inc_all_pages = 0; | |
d1310b2e | 3299 | unsigned long num_pages; |
a86c12c7 | 3300 | struct bio *bio = NULL; |
c8b97818 | 3301 | unsigned long bio_flags = 0; |
a86c12c7 | 3302 | |
b4ce94de | 3303 | if (test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags)) |
d1310b2e CM |
3304 | return 0; |
3305 | ||
ce9adaa5 | 3306 | if (test_range_bit(tree, eb->start, eb->start + eb->len - 1, |
d1310b2e CM |
3307 | EXTENT_UPTODATE, 1)) { |
3308 | return 0; | |
3309 | } | |
3310 | ||
3311 | if (start) { | |
3312 | WARN_ON(start < eb->start); | |
3313 | start_i = (start >> PAGE_CACHE_SHIFT) - | |
3314 | (eb->start >> PAGE_CACHE_SHIFT); | |
3315 | } else { | |
3316 | start_i = 0; | |
3317 | } | |
3318 | ||
3319 | num_pages = num_extent_pages(eb->start, eb->len); | |
3320 | for (i = start_i; i < num_pages; i++) { | |
3321 | page = extent_buffer_page(eb, i); | |
d1310b2e | 3322 | if (!wait) { |
2db04966 | 3323 | if (!trylock_page(page)) |
ce9adaa5 | 3324 | goto unlock_exit; |
d1310b2e CM |
3325 | } else { |
3326 | lock_page(page); | |
3327 | } | |
ce9adaa5 | 3328 | locked_pages++; |
d397712b | 3329 | if (!PageUptodate(page)) |
ce9adaa5 | 3330 | all_uptodate = 0; |
ce9adaa5 CM |
3331 | } |
3332 | if (all_uptodate) { | |
3333 | if (start_i == 0) | |
b4ce94de | 3334 | set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags); |
ce9adaa5 CM |
3335 | goto unlock_exit; |
3336 | } | |
3337 | ||
3338 | for (i = start_i; i < num_pages; i++) { | |
3339 | page = extent_buffer_page(eb, i); | |
3340 | if (inc_all_pages) | |
3341 | page_cache_get(page); | |
3342 | if (!PageUptodate(page)) { | |
3343 | if (start_i == 0) | |
3344 | inc_all_pages = 1; | |
f188591e | 3345 | ClearPageError(page); |
a86c12c7 | 3346 | err = __extent_read_full_page(tree, page, |
f188591e | 3347 | get_extent, &bio, |
c8b97818 | 3348 | mirror_num, &bio_flags); |
d397712b | 3349 | if (err) |
d1310b2e | 3350 | ret = err; |
d1310b2e CM |
3351 | } else { |
3352 | unlock_page(page); | |
3353 | } | |
3354 | } | |
3355 | ||
a86c12c7 | 3356 | if (bio) |
c8b97818 | 3357 | submit_one_bio(READ, bio, mirror_num, bio_flags); |
a86c12c7 | 3358 | |
d397712b | 3359 | if (ret || !wait) |
d1310b2e | 3360 | return ret; |
d397712b | 3361 | |
d1310b2e CM |
3362 | for (i = start_i; i < num_pages; i++) { |
3363 | page = extent_buffer_page(eb, i); | |
3364 | wait_on_page_locked(page); | |
d397712b | 3365 | if (!PageUptodate(page)) |
d1310b2e | 3366 | ret = -EIO; |
d1310b2e | 3367 | } |
d397712b | 3368 | |
d1310b2e | 3369 | if (!ret) |
b4ce94de | 3370 | set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags); |
d1310b2e | 3371 | return ret; |
ce9adaa5 CM |
3372 | |
3373 | unlock_exit: | |
3374 | i = start_i; | |
d397712b | 3375 | while (locked_pages > 0) { |
ce9adaa5 CM |
3376 | page = extent_buffer_page(eb, i); |
3377 | i++; | |
3378 | unlock_page(page); | |
3379 | locked_pages--; | |
3380 | } | |
3381 | return ret; | |
d1310b2e | 3382 | } |
d1310b2e CM |
3383 | |
3384 | void read_extent_buffer(struct extent_buffer *eb, void *dstv, | |
3385 | unsigned long start, | |
3386 | unsigned long len) | |
3387 | { | |
3388 | size_t cur; | |
3389 | size_t offset; | |
3390 | struct page *page; | |
3391 | char *kaddr; | |
3392 | char *dst = (char *)dstv; | |
3393 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3394 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
d1310b2e CM |
3395 | |
3396 | WARN_ON(start > eb->len); | |
3397 | WARN_ON(start + len > eb->start + eb->len); | |
3398 | ||
3399 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3400 | ||
d397712b | 3401 | while (len > 0) { |
d1310b2e | 3402 | page = extent_buffer_page(eb, i); |
d1310b2e CM |
3403 | |
3404 | cur = min(len, (PAGE_CACHE_SIZE - offset)); | |
3405 | kaddr = kmap_atomic(page, KM_USER1); | |
3406 | memcpy(dst, kaddr + offset, cur); | |
3407 | kunmap_atomic(kaddr, KM_USER1); | |
3408 | ||
3409 | dst += cur; | |
3410 | len -= cur; | |
3411 | offset = 0; | |
3412 | i++; | |
3413 | } | |
3414 | } | |
d1310b2e CM |
3415 | |
3416 | int map_private_extent_buffer(struct extent_buffer *eb, unsigned long start, | |
3417 | unsigned long min_len, char **token, char **map, | |
3418 | unsigned long *map_start, | |
3419 | unsigned long *map_len, int km) | |
3420 | { | |
3421 | size_t offset = start & (PAGE_CACHE_SIZE - 1); | |
3422 | char *kaddr; | |
3423 | struct page *p; | |
3424 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3425 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
3426 | unsigned long end_i = (start_offset + start + min_len - 1) >> | |
3427 | PAGE_CACHE_SHIFT; | |
3428 | ||
3429 | if (i != end_i) | |
3430 | return -EINVAL; | |
3431 | ||
3432 | if (i == 0) { | |
3433 | offset = start_offset; | |
3434 | *map_start = 0; | |
3435 | } else { | |
3436 | offset = 0; | |
3437 | *map_start = ((u64)i << PAGE_CACHE_SHIFT) - start_offset; | |
3438 | } | |
d397712b | 3439 | |
d1310b2e | 3440 | if (start + min_len > eb->len) { |
d397712b CM |
3441 | printk(KERN_ERR "btrfs bad mapping eb start %llu len %lu, " |
3442 | "wanted %lu %lu\n", (unsigned long long)eb->start, | |
3443 | eb->len, start, min_len); | |
d1310b2e CM |
3444 | WARN_ON(1); |
3445 | } | |
3446 | ||
3447 | p = extent_buffer_page(eb, i); | |
d1310b2e CM |
3448 | kaddr = kmap_atomic(p, km); |
3449 | *token = kaddr; | |
3450 | *map = kaddr + offset; | |
3451 | *map_len = PAGE_CACHE_SIZE - offset; | |
3452 | return 0; | |
3453 | } | |
d1310b2e CM |
3454 | |
3455 | int map_extent_buffer(struct extent_buffer *eb, unsigned long start, | |
3456 | unsigned long min_len, | |
3457 | char **token, char **map, | |
3458 | unsigned long *map_start, | |
3459 | unsigned long *map_len, int km) | |
3460 | { | |
3461 | int err; | |
3462 | int save = 0; | |
3463 | if (eb->map_token) { | |
3464 | unmap_extent_buffer(eb, eb->map_token, km); | |
3465 | eb->map_token = NULL; | |
3466 | save = 1; | |
3467 | } | |
3468 | err = map_private_extent_buffer(eb, start, min_len, token, map, | |
3469 | map_start, map_len, km); | |
3470 | if (!err && save) { | |
3471 | eb->map_token = *token; | |
3472 | eb->kaddr = *map; | |
3473 | eb->map_start = *map_start; | |
3474 | eb->map_len = *map_len; | |
3475 | } | |
3476 | return err; | |
3477 | } | |
d1310b2e CM |
3478 | |
3479 | void unmap_extent_buffer(struct extent_buffer *eb, char *token, int km) | |
3480 | { | |
3481 | kunmap_atomic(token, km); | |
3482 | } | |
d1310b2e CM |
3483 | |
3484 | int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv, | |
3485 | unsigned long start, | |
3486 | unsigned long len) | |
3487 | { | |
3488 | size_t cur; | |
3489 | size_t offset; | |
3490 | struct page *page; | |
3491 | char *kaddr; | |
3492 | char *ptr = (char *)ptrv; | |
3493 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3494 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
3495 | int ret = 0; | |
3496 | ||
3497 | WARN_ON(start > eb->len); | |
3498 | WARN_ON(start + len > eb->start + eb->len); | |
3499 | ||
3500 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3501 | ||
d397712b | 3502 | while (len > 0) { |
d1310b2e | 3503 | page = extent_buffer_page(eb, i); |
d1310b2e CM |
3504 | |
3505 | cur = min(len, (PAGE_CACHE_SIZE - offset)); | |
3506 | ||
3507 | kaddr = kmap_atomic(page, KM_USER0); | |
3508 | ret = memcmp(ptr, kaddr + offset, cur); | |
3509 | kunmap_atomic(kaddr, KM_USER0); | |
3510 | if (ret) | |
3511 | break; | |
3512 | ||
3513 | ptr += cur; | |
3514 | len -= cur; | |
3515 | offset = 0; | |
3516 | i++; | |
3517 | } | |
3518 | return ret; | |
3519 | } | |
d1310b2e CM |
3520 | |
3521 | void write_extent_buffer(struct extent_buffer *eb, const void *srcv, | |
3522 | unsigned long start, unsigned long len) | |
3523 | { | |
3524 | size_t cur; | |
3525 | size_t offset; | |
3526 | struct page *page; | |
3527 | char *kaddr; | |
3528 | char *src = (char *)srcv; | |
3529 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3530 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
3531 | ||
3532 | WARN_ON(start > eb->len); | |
3533 | WARN_ON(start + len > eb->start + eb->len); | |
3534 | ||
3535 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3536 | ||
d397712b | 3537 | while (len > 0) { |
d1310b2e CM |
3538 | page = extent_buffer_page(eb, i); |
3539 | WARN_ON(!PageUptodate(page)); | |
3540 | ||
3541 | cur = min(len, PAGE_CACHE_SIZE - offset); | |
3542 | kaddr = kmap_atomic(page, KM_USER1); | |
3543 | memcpy(kaddr + offset, src, cur); | |
3544 | kunmap_atomic(kaddr, KM_USER1); | |
3545 | ||
3546 | src += cur; | |
3547 | len -= cur; | |
3548 | offset = 0; | |
3549 | i++; | |
3550 | } | |
3551 | } | |
d1310b2e CM |
3552 | |
3553 | void memset_extent_buffer(struct extent_buffer *eb, char c, | |
3554 | unsigned long start, unsigned long len) | |
3555 | { | |
3556 | size_t cur; | |
3557 | size_t offset; | |
3558 | struct page *page; | |
3559 | char *kaddr; | |
3560 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3561 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
3562 | ||
3563 | WARN_ON(start > eb->len); | |
3564 | WARN_ON(start + len > eb->start + eb->len); | |
3565 | ||
3566 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3567 | ||
d397712b | 3568 | while (len > 0) { |
d1310b2e CM |
3569 | page = extent_buffer_page(eb, i); |
3570 | WARN_ON(!PageUptodate(page)); | |
3571 | ||
3572 | cur = min(len, PAGE_CACHE_SIZE - offset); | |
3573 | kaddr = kmap_atomic(page, KM_USER0); | |
3574 | memset(kaddr + offset, c, cur); | |
3575 | kunmap_atomic(kaddr, KM_USER0); | |
3576 | ||
3577 | len -= cur; | |
3578 | offset = 0; | |
3579 | i++; | |
3580 | } | |
3581 | } | |
d1310b2e CM |
3582 | |
3583 | void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src, | |
3584 | unsigned long dst_offset, unsigned long src_offset, | |
3585 | unsigned long len) | |
3586 | { | |
3587 | u64 dst_len = dst->len; | |
3588 | size_t cur; | |
3589 | size_t offset; | |
3590 | struct page *page; | |
3591 | char *kaddr; | |
3592 | size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3593 | unsigned long i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT; | |
3594 | ||
3595 | WARN_ON(src->len != dst_len); | |
3596 | ||
3597 | offset = (start_offset + dst_offset) & | |
3598 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3599 | ||
d397712b | 3600 | while (len > 0) { |
d1310b2e CM |
3601 | page = extent_buffer_page(dst, i); |
3602 | WARN_ON(!PageUptodate(page)); | |
3603 | ||
3604 | cur = min(len, (unsigned long)(PAGE_CACHE_SIZE - offset)); | |
3605 | ||
3606 | kaddr = kmap_atomic(page, KM_USER0); | |
3607 | read_extent_buffer(src, kaddr + offset, src_offset, cur); | |
3608 | kunmap_atomic(kaddr, KM_USER0); | |
3609 | ||
3610 | src_offset += cur; | |
3611 | len -= cur; | |
3612 | offset = 0; | |
3613 | i++; | |
3614 | } | |
3615 | } | |
d1310b2e CM |
3616 | |
3617 | static void move_pages(struct page *dst_page, struct page *src_page, | |
3618 | unsigned long dst_off, unsigned long src_off, | |
3619 | unsigned long len) | |
3620 | { | |
3621 | char *dst_kaddr = kmap_atomic(dst_page, KM_USER0); | |
3622 | if (dst_page == src_page) { | |
3623 | memmove(dst_kaddr + dst_off, dst_kaddr + src_off, len); | |
3624 | } else { | |
3625 | char *src_kaddr = kmap_atomic(src_page, KM_USER1); | |
3626 | char *p = dst_kaddr + dst_off + len; | |
3627 | char *s = src_kaddr + src_off + len; | |
3628 | ||
3629 | while (len--) | |
3630 | *--p = *--s; | |
3631 | ||
3632 | kunmap_atomic(src_kaddr, KM_USER1); | |
3633 | } | |
3634 | kunmap_atomic(dst_kaddr, KM_USER0); | |
3635 | } | |
3636 | ||
3637 | static void copy_pages(struct page *dst_page, struct page *src_page, | |
3638 | unsigned long dst_off, unsigned long src_off, | |
3639 | unsigned long len) | |
3640 | { | |
3641 | char *dst_kaddr = kmap_atomic(dst_page, KM_USER0); | |
3642 | char *src_kaddr; | |
3643 | ||
3644 | if (dst_page != src_page) | |
3645 | src_kaddr = kmap_atomic(src_page, KM_USER1); | |
3646 | else | |
3647 | src_kaddr = dst_kaddr; | |
3648 | ||
3649 | memcpy(dst_kaddr + dst_off, src_kaddr + src_off, len); | |
3650 | kunmap_atomic(dst_kaddr, KM_USER0); | |
3651 | if (dst_page != src_page) | |
3652 | kunmap_atomic(src_kaddr, KM_USER1); | |
3653 | } | |
3654 | ||
3655 | void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, | |
3656 | unsigned long src_offset, unsigned long len) | |
3657 | { | |
3658 | size_t cur; | |
3659 | size_t dst_off_in_page; | |
3660 | size_t src_off_in_page; | |
3661 | size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3662 | unsigned long dst_i; | |
3663 | unsigned long src_i; | |
3664 | ||
3665 | if (src_offset + len > dst->len) { | |
d397712b CM |
3666 | printk(KERN_ERR "btrfs memmove bogus src_offset %lu move " |
3667 | "len %lu dst len %lu\n", src_offset, len, dst->len); | |
d1310b2e CM |
3668 | BUG_ON(1); |
3669 | } | |
3670 | if (dst_offset + len > dst->len) { | |
d397712b CM |
3671 | printk(KERN_ERR "btrfs memmove bogus dst_offset %lu move " |
3672 | "len %lu dst len %lu\n", dst_offset, len, dst->len); | |
d1310b2e CM |
3673 | BUG_ON(1); |
3674 | } | |
3675 | ||
d397712b | 3676 | while (len > 0) { |
d1310b2e CM |
3677 | dst_off_in_page = (start_offset + dst_offset) & |
3678 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3679 | src_off_in_page = (start_offset + src_offset) & | |
3680 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3681 | ||
3682 | dst_i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT; | |
3683 | src_i = (start_offset + src_offset) >> PAGE_CACHE_SHIFT; | |
3684 | ||
3685 | cur = min(len, (unsigned long)(PAGE_CACHE_SIZE - | |
3686 | src_off_in_page)); | |
3687 | cur = min_t(unsigned long, cur, | |
3688 | (unsigned long)(PAGE_CACHE_SIZE - dst_off_in_page)); | |
3689 | ||
3690 | copy_pages(extent_buffer_page(dst, dst_i), | |
3691 | extent_buffer_page(dst, src_i), | |
3692 | dst_off_in_page, src_off_in_page, cur); | |
3693 | ||
3694 | src_offset += cur; | |
3695 | dst_offset += cur; | |
3696 | len -= cur; | |
3697 | } | |
3698 | } | |
d1310b2e CM |
3699 | |
3700 | void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, | |
3701 | unsigned long src_offset, unsigned long len) | |
3702 | { | |
3703 | size_t cur; | |
3704 | size_t dst_off_in_page; | |
3705 | size_t src_off_in_page; | |
3706 | unsigned long dst_end = dst_offset + len - 1; | |
3707 | unsigned long src_end = src_offset + len - 1; | |
3708 | size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3709 | unsigned long dst_i; | |
3710 | unsigned long src_i; | |
3711 | ||
3712 | if (src_offset + len > dst->len) { | |
d397712b CM |
3713 | printk(KERN_ERR "btrfs memmove bogus src_offset %lu move " |
3714 | "len %lu len %lu\n", src_offset, len, dst->len); | |
d1310b2e CM |
3715 | BUG_ON(1); |
3716 | } | |
3717 | if (dst_offset + len > dst->len) { | |
d397712b CM |
3718 | printk(KERN_ERR "btrfs memmove bogus dst_offset %lu move " |
3719 | "len %lu len %lu\n", dst_offset, len, dst->len); | |
d1310b2e CM |
3720 | BUG_ON(1); |
3721 | } | |
3722 | if (dst_offset < src_offset) { | |
3723 | memcpy_extent_buffer(dst, dst_offset, src_offset, len); | |
3724 | return; | |
3725 | } | |
d397712b | 3726 | while (len > 0) { |
d1310b2e CM |
3727 | dst_i = (start_offset + dst_end) >> PAGE_CACHE_SHIFT; |
3728 | src_i = (start_offset + src_end) >> PAGE_CACHE_SHIFT; | |
3729 | ||
3730 | dst_off_in_page = (start_offset + dst_end) & | |
3731 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3732 | src_off_in_page = (start_offset + src_end) & | |
3733 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3734 | ||
3735 | cur = min_t(unsigned long, len, src_off_in_page + 1); | |
3736 | cur = min(cur, dst_off_in_page + 1); | |
3737 | move_pages(extent_buffer_page(dst, dst_i), | |
3738 | extent_buffer_page(dst, src_i), | |
3739 | dst_off_in_page - cur + 1, | |
3740 | src_off_in_page - cur + 1, cur); | |
3741 | ||
3742 | dst_end -= cur; | |
3743 | src_end -= cur; | |
3744 | len -= cur; | |
3745 | } | |
3746 | } | |
6af118ce CM |
3747 | |
3748 | int try_release_extent_buffer(struct extent_io_tree *tree, struct page *page) | |
3749 | { | |
3750 | u64 start = page_offset(page); | |
3751 | struct extent_buffer *eb; | |
3752 | int ret = 1; | |
3753 | unsigned long i; | |
3754 | unsigned long num_pages; | |
3755 | ||
3756 | spin_lock(&tree->buffer_lock); | |
3757 | eb = buffer_search(tree, start); | |
3758 | if (!eb) | |
3759 | goto out; | |
3760 | ||
3761 | if (atomic_read(&eb->refs) > 1) { | |
3762 | ret = 0; | |
3763 | goto out; | |
3764 | } | |
b9473439 CM |
3765 | if (test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)) { |
3766 | ret = 0; | |
3767 | goto out; | |
3768 | } | |
6af118ce CM |
3769 | /* at this point we can safely release the extent buffer */ |
3770 | num_pages = num_extent_pages(eb->start, eb->len); | |
b214107e CH |
3771 | for (i = 0; i < num_pages; i++) |
3772 | page_cache_release(extent_buffer_page(eb, i)); | |
6af118ce CM |
3773 | rb_erase(&eb->rb_node, &tree->buffer); |
3774 | __free_extent_buffer(eb); | |
3775 | out: | |
3776 | spin_unlock(&tree->buffer_lock); | |
3777 | return ret; | |
3778 | } |