Commit | Line | Data |
---|---|---|
a52d9a80 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> | |
4dc11904 | 11 | #include <linux/swap.h> |
0a2118df | 12 | #include <linux/version.h> |
a52d9a80 CM |
13 | #include "extent_map.h" |
14 | ||
86479a04 CM |
15 | /* temporary define until extent_map moves out of btrfs */ |
16 | struct kmem_cache *btrfs_cache_create(const char *name, size_t size, | |
17 | unsigned long extra_flags, | |
18 | void (*ctor)(void *, struct kmem_cache *, | |
19 | unsigned long)); | |
20 | ||
a52d9a80 CM |
21 | static struct kmem_cache *extent_map_cache; |
22 | static struct kmem_cache *extent_state_cache; | |
6d36dcd4 | 23 | static struct kmem_cache *extent_buffer_cache; |
f510cfec | 24 | |
f510cfec CM |
25 | static LIST_HEAD(buffers); |
26 | static LIST_HEAD(states); | |
27 | ||
f510cfec | 28 | static spinlock_t state_lock = SPIN_LOCK_UNLOCKED; |
4dc11904 | 29 | #define BUFFER_LRU_MAX 64 |
a52d9a80 CM |
30 | |
31 | struct tree_entry { | |
32 | u64 start; | |
33 | u64 end; | |
34 | int in_tree; | |
35 | struct rb_node rb_node; | |
36 | }; | |
37 | ||
a52d9a80 CM |
38 | void __init extent_map_init(void) |
39 | { | |
86479a04 | 40 | extent_map_cache = btrfs_cache_create("extent_map", |
6d36dcd4 | 41 | sizeof(struct extent_map), 0, |
a52d9a80 | 42 | NULL); |
86479a04 | 43 | extent_state_cache = btrfs_cache_create("extent_state", |
6d36dcd4 | 44 | sizeof(struct extent_state), 0, |
a52d9a80 | 45 | NULL); |
6d36dcd4 CM |
46 | extent_buffer_cache = btrfs_cache_create("extent_buffers", |
47 | sizeof(struct extent_buffer), 0, | |
48 | NULL); | |
a52d9a80 CM |
49 | } |
50 | ||
51 | void __exit extent_map_exit(void) | |
52 | { | |
f510cfec | 53 | struct extent_state *state; |
6d36dcd4 | 54 | |
f510cfec CM |
55 | while (!list_empty(&states)) { |
56 | state = list_entry(states.next, struct extent_state, list); | |
57 | printk("state leak: start %Lu end %Lu state %lu in tree %d refs %d\n", state->start, state->end, state->state, state->in_tree, atomic_read(&state->refs)); | |
58 | list_del(&state->list); | |
59 | kmem_cache_free(extent_state_cache, state); | |
60 | ||
61 | } | |
f510cfec | 62 | |
a52d9a80 CM |
63 | if (extent_map_cache) |
64 | kmem_cache_destroy(extent_map_cache); | |
65 | if (extent_state_cache) | |
66 | kmem_cache_destroy(extent_state_cache); | |
6d36dcd4 CM |
67 | if (extent_buffer_cache) |
68 | kmem_cache_destroy(extent_buffer_cache); | |
a52d9a80 CM |
69 | } |
70 | ||
71 | void extent_map_tree_init(struct extent_map_tree *tree, | |
72 | struct address_space *mapping, gfp_t mask) | |
73 | { | |
74 | tree->map.rb_node = NULL; | |
75 | tree->state.rb_node = NULL; | |
07157aac | 76 | tree->ops = NULL; |
a52d9a80 | 77 | rwlock_init(&tree->lock); |
4dc11904 | 78 | spin_lock_init(&tree->lru_lock); |
a52d9a80 | 79 | tree->mapping = mapping; |
4dc11904 CM |
80 | INIT_LIST_HEAD(&tree->buffer_lru); |
81 | tree->lru_size = 0; | |
a52d9a80 CM |
82 | } |
83 | EXPORT_SYMBOL(extent_map_tree_init); | |
84 | ||
19c00ddc | 85 | void extent_map_tree_empty_lru(struct extent_map_tree *tree) |
4dc11904 CM |
86 | { |
87 | struct extent_buffer *eb; | |
88 | while(!list_empty(&tree->buffer_lru)) { | |
89 | eb = list_entry(tree->buffer_lru.next, struct extent_buffer, | |
90 | lru); | |
91 | list_del(&eb->lru); | |
92 | free_extent_buffer(eb); | |
93 | } | |
94 | } | |
19c00ddc | 95 | EXPORT_SYMBOL(extent_map_tree_empty_lru); |
4dc11904 | 96 | |
a52d9a80 CM |
97 | struct extent_map *alloc_extent_map(gfp_t mask) |
98 | { | |
99 | struct extent_map *em; | |
100 | em = kmem_cache_alloc(extent_map_cache, mask); | |
101 | if (!em || IS_ERR(em)) | |
102 | return em; | |
103 | em->in_tree = 0; | |
104 | atomic_set(&em->refs, 1); | |
105 | return em; | |
106 | } | |
107 | EXPORT_SYMBOL(alloc_extent_map); | |
108 | ||
109 | void free_extent_map(struct extent_map *em) | |
110 | { | |
2bf5a725 CM |
111 | if (!em) |
112 | return; | |
a52d9a80 CM |
113 | if (atomic_dec_and_test(&em->refs)) { |
114 | WARN_ON(em->in_tree); | |
115 | kmem_cache_free(extent_map_cache, em); | |
116 | } | |
117 | } | |
118 | EXPORT_SYMBOL(free_extent_map); | |
119 | ||
120 | ||
121 | struct extent_state *alloc_extent_state(gfp_t mask) | |
122 | { | |
123 | struct extent_state *state; | |
f510cfec CM |
124 | unsigned long flags; |
125 | ||
a52d9a80 CM |
126 | state = kmem_cache_alloc(extent_state_cache, mask); |
127 | if (!state || IS_ERR(state)) | |
128 | return state; | |
129 | state->state = 0; | |
130 | state->in_tree = 0; | |
07157aac | 131 | state->private = 0; |
f510cfec CM |
132 | |
133 | spin_lock_irqsave(&state_lock, flags); | |
134 | list_add(&state->list, &states); | |
135 | spin_unlock_irqrestore(&state_lock, flags); | |
136 | ||
a52d9a80 CM |
137 | atomic_set(&state->refs, 1); |
138 | init_waitqueue_head(&state->wq); | |
a52d9a80 CM |
139 | return state; |
140 | } | |
141 | EXPORT_SYMBOL(alloc_extent_state); | |
142 | ||
143 | void free_extent_state(struct extent_state *state) | |
144 | { | |
f510cfec | 145 | unsigned long flags; |
2bf5a725 CM |
146 | if (!state) |
147 | return; | |
a52d9a80 CM |
148 | if (atomic_dec_and_test(&state->refs)) { |
149 | WARN_ON(state->in_tree); | |
f510cfec CM |
150 | spin_lock_irqsave(&state_lock, flags); |
151 | list_del(&state->list); | |
152 | spin_unlock_irqrestore(&state_lock, flags); | |
a52d9a80 CM |
153 | kmem_cache_free(extent_state_cache, state); |
154 | } | |
155 | } | |
156 | EXPORT_SYMBOL(free_extent_state); | |
157 | ||
158 | static struct rb_node *tree_insert(struct rb_root *root, u64 offset, | |
159 | struct rb_node *node) | |
160 | { | |
161 | struct rb_node ** p = &root->rb_node; | |
162 | struct rb_node * parent = NULL; | |
163 | struct tree_entry *entry; | |
164 | ||
165 | while(*p) { | |
166 | parent = *p; | |
167 | entry = rb_entry(parent, struct tree_entry, rb_node); | |
168 | ||
169 | if (offset < entry->start) | |
170 | p = &(*p)->rb_left; | |
171 | else if (offset > entry->end) | |
172 | p = &(*p)->rb_right; | |
173 | else | |
174 | return parent; | |
175 | } | |
176 | ||
177 | entry = rb_entry(node, struct tree_entry, rb_node); | |
178 | entry->in_tree = 1; | |
179 | rb_link_node(node, parent, p); | |
180 | rb_insert_color(node, root); | |
181 | return NULL; | |
182 | } | |
183 | ||
184 | static struct rb_node *__tree_search(struct rb_root *root, u64 offset, | |
185 | struct rb_node **prev_ret) | |
186 | { | |
187 | struct rb_node * n = root->rb_node; | |
188 | struct rb_node *prev = NULL; | |
189 | struct tree_entry *entry; | |
190 | struct tree_entry *prev_entry = NULL; | |
191 | ||
192 | while(n) { | |
193 | entry = rb_entry(n, struct tree_entry, rb_node); | |
194 | prev = n; | |
195 | prev_entry = entry; | |
196 | ||
197 | if (offset < entry->start) | |
198 | n = n->rb_left; | |
199 | else if (offset > entry->end) | |
200 | n = n->rb_right; | |
201 | else | |
202 | return n; | |
203 | } | |
204 | if (!prev_ret) | |
205 | return NULL; | |
206 | while(prev && offset > prev_entry->end) { | |
207 | prev = rb_next(prev); | |
208 | prev_entry = rb_entry(prev, struct tree_entry, rb_node); | |
209 | } | |
210 | *prev_ret = prev; | |
211 | return NULL; | |
212 | } | |
213 | ||
214 | static inline struct rb_node *tree_search(struct rb_root *root, u64 offset) | |
215 | { | |
216 | struct rb_node *prev; | |
217 | struct rb_node *ret; | |
218 | ret = __tree_search(root, offset, &prev); | |
219 | if (!ret) | |
220 | return prev; | |
221 | return ret; | |
222 | } | |
223 | ||
224 | static int tree_delete(struct rb_root *root, u64 offset) | |
225 | { | |
226 | struct rb_node *node; | |
227 | struct tree_entry *entry; | |
228 | ||
229 | node = __tree_search(root, offset, NULL); | |
230 | if (!node) | |
231 | return -ENOENT; | |
232 | entry = rb_entry(node, struct tree_entry, rb_node); | |
233 | entry->in_tree = 0; | |
234 | rb_erase(node, root); | |
235 | return 0; | |
236 | } | |
237 | ||
238 | /* | |
239 | * add_extent_mapping tries a simple backward merge with existing | |
240 | * mappings. The extent_map struct passed in will be inserted into | |
241 | * the tree directly (no copies made, just a reference taken). | |
242 | */ | |
243 | int add_extent_mapping(struct extent_map_tree *tree, | |
244 | struct extent_map *em) | |
245 | { | |
246 | int ret = 0; | |
247 | struct extent_map *prev = NULL; | |
248 | struct rb_node *rb; | |
249 | ||
250 | write_lock_irq(&tree->lock); | |
251 | rb = tree_insert(&tree->map, em->end, &em->rb_node); | |
252 | if (rb) { | |
253 | prev = rb_entry(rb, struct extent_map, rb_node); | |
254 | printk("found extent map %Lu %Lu on insert of %Lu %Lu\n", prev->start, prev->end, em->start, em->end); | |
255 | ret = -EEXIST; | |
256 | goto out; | |
257 | } | |
258 | atomic_inc(&em->refs); | |
259 | if (em->start != 0) { | |
260 | rb = rb_prev(&em->rb_node); | |
261 | if (rb) | |
262 | prev = rb_entry(rb, struct extent_map, rb_node); | |
263 | if (prev && prev->end + 1 == em->start && | |
5f39d397 CM |
264 | ((em->block_start == EXTENT_MAP_HOLE && |
265 | prev->block_start == EXTENT_MAP_HOLE) || | |
a52d9a80 CM |
266 | (em->block_start == prev->block_end + 1))) { |
267 | em->start = prev->start; | |
268 | em->block_start = prev->block_start; | |
269 | rb_erase(&prev->rb_node, &tree->map); | |
270 | prev->in_tree = 0; | |
271 | free_extent_map(prev); | |
272 | } | |
273 | } | |
274 | out: | |
275 | write_unlock_irq(&tree->lock); | |
276 | return ret; | |
277 | } | |
278 | EXPORT_SYMBOL(add_extent_mapping); | |
279 | ||
280 | /* | |
281 | * lookup_extent_mapping returns the first extent_map struct in the | |
282 | * tree that intersects the [start, end] (inclusive) range. There may | |
283 | * be additional objects in the tree that intersect, so check the object | |
284 | * returned carefully to make sure you don't need additional lookups. | |
285 | */ | |
286 | struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree, | |
287 | u64 start, u64 end) | |
288 | { | |
289 | struct extent_map *em; | |
290 | struct rb_node *rb_node; | |
291 | ||
292 | read_lock_irq(&tree->lock); | |
293 | rb_node = tree_search(&tree->map, start); | |
294 | if (!rb_node) { | |
295 | em = NULL; | |
296 | goto out; | |
297 | } | |
298 | if (IS_ERR(rb_node)) { | |
299 | em = ERR_PTR(PTR_ERR(rb_node)); | |
300 | goto out; | |
301 | } | |
302 | em = rb_entry(rb_node, struct extent_map, rb_node); | |
303 | if (em->end < start || em->start > end) { | |
304 | em = NULL; | |
305 | goto out; | |
306 | } | |
307 | atomic_inc(&em->refs); | |
308 | out: | |
309 | read_unlock_irq(&tree->lock); | |
310 | return em; | |
311 | } | |
312 | EXPORT_SYMBOL(lookup_extent_mapping); | |
313 | ||
314 | /* | |
315 | * removes an extent_map struct from the tree. No reference counts are | |
316 | * dropped, and no checks are done to see if the range is in use | |
317 | */ | |
318 | int remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em) | |
319 | { | |
320 | int ret; | |
321 | ||
322 | write_lock_irq(&tree->lock); | |
323 | ret = tree_delete(&tree->map, em->end); | |
324 | write_unlock_irq(&tree->lock); | |
325 | return ret; | |
326 | } | |
327 | EXPORT_SYMBOL(remove_extent_mapping); | |
328 | ||
329 | /* | |
330 | * utility function to look for merge candidates inside a given range. | |
331 | * Any extents with matching state are merged together into a single | |
332 | * extent in the tree. Extents with EXTENT_IO in their state field | |
333 | * are not merged because the end_io handlers need to be able to do | |
334 | * operations on them without sleeping (or doing allocations/splits). | |
335 | * | |
336 | * This should be called with the tree lock held. | |
337 | */ | |
338 | static int merge_state(struct extent_map_tree *tree, | |
339 | struct extent_state *state) | |
340 | { | |
341 | struct extent_state *other; | |
342 | struct rb_node *other_node; | |
343 | ||
344 | if (state->state & EXTENT_IOBITS) | |
345 | return 0; | |
346 | ||
347 | other_node = rb_prev(&state->rb_node); | |
348 | if (other_node) { | |
349 | other = rb_entry(other_node, struct extent_state, rb_node); | |
350 | if (other->end == state->start - 1 && | |
351 | other->state == state->state) { | |
352 | state->start = other->start; | |
353 | other->in_tree = 0; | |
354 | rb_erase(&other->rb_node, &tree->state); | |
355 | free_extent_state(other); | |
356 | } | |
357 | } | |
358 | other_node = rb_next(&state->rb_node); | |
359 | if (other_node) { | |
360 | other = rb_entry(other_node, struct extent_state, rb_node); | |
361 | if (other->start == state->end + 1 && | |
362 | other->state == state->state) { | |
363 | other->start = state->start; | |
364 | state->in_tree = 0; | |
365 | rb_erase(&state->rb_node, &tree->state); | |
366 | free_extent_state(state); | |
367 | } | |
368 | } | |
369 | return 0; | |
370 | } | |
371 | ||
372 | /* | |
373 | * insert an extent_state struct into the tree. 'bits' are set on the | |
374 | * struct before it is inserted. | |
375 | * | |
376 | * This may return -EEXIST if the extent is already there, in which case the | |
377 | * state struct is freed. | |
378 | * | |
379 | * The tree lock is not taken internally. This is a utility function and | |
380 | * probably isn't what you want to call (see set/clear_extent_bit). | |
381 | */ | |
382 | static int insert_state(struct extent_map_tree *tree, | |
383 | struct extent_state *state, u64 start, u64 end, | |
384 | int bits) | |
385 | { | |
386 | struct rb_node *node; | |
387 | ||
388 | if (end < start) { | |
389 | printk("end < start %Lu %Lu\n", end, start); | |
390 | WARN_ON(1); | |
391 | } | |
392 | state->state |= bits; | |
393 | state->start = start; | |
394 | state->end = end; | |
a52d9a80 CM |
395 | node = tree_insert(&tree->state, end, &state->rb_node); |
396 | if (node) { | |
397 | struct extent_state *found; | |
398 | found = rb_entry(node, struct extent_state, rb_node); | |
b888db2b | 399 | printk("found node %Lu %Lu on insert of %Lu %Lu\n", found->start, found->end, start, end); |
a52d9a80 CM |
400 | free_extent_state(state); |
401 | return -EEXIST; | |
402 | } | |
403 | merge_state(tree, state); | |
404 | return 0; | |
405 | } | |
406 | ||
407 | /* | |
408 | * split a given extent state struct in two, inserting the preallocated | |
409 | * struct 'prealloc' as the newly created second half. 'split' indicates an | |
410 | * offset inside 'orig' where it should be split. | |
411 | * | |
412 | * Before calling, | |
413 | * the tree has 'orig' at [orig->start, orig->end]. After calling, there | |
414 | * are two extent state structs in the tree: | |
415 | * prealloc: [orig->start, split - 1] | |
416 | * orig: [ split, orig->end ] | |
417 | * | |
418 | * The tree locks are not taken by this function. They need to be held | |
419 | * by the caller. | |
420 | */ | |
421 | static int split_state(struct extent_map_tree *tree, struct extent_state *orig, | |
422 | struct extent_state *prealloc, u64 split) | |
423 | { | |
424 | struct rb_node *node; | |
425 | prealloc->start = orig->start; | |
426 | prealloc->end = split - 1; | |
427 | prealloc->state = orig->state; | |
428 | orig->start = split; | |
f510cfec | 429 | |
a52d9a80 CM |
430 | node = tree_insert(&tree->state, prealloc->end, &prealloc->rb_node); |
431 | if (node) { | |
432 | struct extent_state *found; | |
433 | found = rb_entry(node, struct extent_state, rb_node); | |
b888db2b | 434 | printk("found node %Lu %Lu on insert of %Lu %Lu\n", found->start, found->end, prealloc->start, prealloc->end); |
a52d9a80 CM |
435 | free_extent_state(prealloc); |
436 | return -EEXIST; | |
437 | } | |
438 | return 0; | |
439 | } | |
440 | ||
441 | /* | |
442 | * utility function to clear some bits in an extent state struct. | |
443 | * it will optionally wake up any one waiting on this state (wake == 1), or | |
444 | * forcibly remove the state from the tree (delete == 1). | |
445 | * | |
446 | * If no bits are set on the state struct after clearing things, the | |
447 | * struct is freed and removed from the tree | |
448 | */ | |
449 | static int clear_state_bit(struct extent_map_tree *tree, | |
450 | struct extent_state *state, int bits, int wake, | |
451 | int delete) | |
452 | { | |
453 | int ret = state->state & bits; | |
454 | state->state &= ~bits; | |
455 | if (wake) | |
456 | wake_up(&state->wq); | |
457 | if (delete || state->state == 0) { | |
458 | if (state->in_tree) { | |
459 | rb_erase(&state->rb_node, &tree->state); | |
460 | state->in_tree = 0; | |
461 | free_extent_state(state); | |
462 | } else { | |
463 | WARN_ON(1); | |
464 | } | |
465 | } else { | |
466 | merge_state(tree, state); | |
467 | } | |
468 | return ret; | |
469 | } | |
470 | ||
471 | /* | |
472 | * clear some bits on a range in the tree. This may require splitting | |
473 | * or inserting elements in the tree, so the gfp mask is used to | |
474 | * indicate which allocations or sleeping are allowed. | |
475 | * | |
476 | * pass 'wake' == 1 to kick any sleepers, and 'delete' == 1 to remove | |
477 | * the given range from the tree regardless of state (ie for truncate). | |
478 | * | |
479 | * the range [start, end] is inclusive. | |
480 | * | |
481 | * This takes the tree lock, and returns < 0 on error, > 0 if any of the | |
482 | * bits were already set, or zero if none of the bits were already set. | |
483 | */ | |
484 | int clear_extent_bit(struct extent_map_tree *tree, u64 start, u64 end, | |
485 | int bits, int wake, int delete, gfp_t mask) | |
486 | { | |
487 | struct extent_state *state; | |
488 | struct extent_state *prealloc = NULL; | |
489 | struct rb_node *node; | |
90f1c19a | 490 | unsigned long flags; |
a52d9a80 CM |
491 | int err; |
492 | int set = 0; | |
493 | ||
494 | again: | |
495 | if (!prealloc && (mask & __GFP_WAIT)) { | |
496 | prealloc = alloc_extent_state(mask); | |
497 | if (!prealloc) | |
498 | return -ENOMEM; | |
499 | } | |
500 | ||
90f1c19a | 501 | write_lock_irqsave(&tree->lock, flags); |
a52d9a80 CM |
502 | /* |
503 | * this search will find the extents that end after | |
504 | * our range starts | |
505 | */ | |
506 | node = tree_search(&tree->state, start); | |
507 | if (!node) | |
508 | goto out; | |
509 | state = rb_entry(node, struct extent_state, rb_node); | |
510 | if (state->start > end) | |
511 | goto out; | |
512 | WARN_ON(state->end < start); | |
513 | ||
514 | /* | |
515 | * | ---- desired range ---- | | |
516 | * | state | or | |
517 | * | ------------- state -------------- | | |
518 | * | |
519 | * We need to split the extent we found, and may flip | |
520 | * bits on second half. | |
521 | * | |
522 | * If the extent we found extends past our range, we | |
523 | * just split and search again. It'll get split again | |
524 | * the next time though. | |
525 | * | |
526 | * If the extent we found is inside our range, we clear | |
527 | * the desired bit on it. | |
528 | */ | |
529 | ||
530 | if (state->start < start) { | |
531 | err = split_state(tree, state, prealloc, start); | |
532 | BUG_ON(err == -EEXIST); | |
533 | prealloc = NULL; | |
534 | if (err) | |
535 | goto out; | |
536 | if (state->end <= end) { | |
537 | start = state->end + 1; | |
538 | set |= clear_state_bit(tree, state, bits, | |
539 | wake, delete); | |
540 | } else { | |
541 | start = state->start; | |
542 | } | |
543 | goto search_again; | |
544 | } | |
545 | /* | |
546 | * | ---- desired range ---- | | |
547 | * | state | | |
548 | * We need to split the extent, and clear the bit | |
549 | * on the first half | |
550 | */ | |
551 | if (state->start <= end && state->end > end) { | |
552 | err = split_state(tree, state, prealloc, end + 1); | |
553 | BUG_ON(err == -EEXIST); | |
554 | ||
555 | if (wake) | |
556 | wake_up(&state->wq); | |
557 | set |= clear_state_bit(tree, prealloc, bits, | |
558 | wake, delete); | |
559 | prealloc = NULL; | |
560 | goto out; | |
561 | } | |
562 | ||
563 | start = state->end + 1; | |
564 | set |= clear_state_bit(tree, state, bits, wake, delete); | |
565 | goto search_again; | |
566 | ||
567 | out: | |
90f1c19a | 568 | write_unlock_irqrestore(&tree->lock, flags); |
a52d9a80 CM |
569 | if (prealloc) |
570 | free_extent_state(prealloc); | |
571 | ||
572 | return set; | |
573 | ||
574 | search_again: | |
96b5179d | 575 | if (start > end) |
a52d9a80 | 576 | goto out; |
90f1c19a | 577 | write_unlock_irqrestore(&tree->lock, flags); |
a52d9a80 CM |
578 | if (mask & __GFP_WAIT) |
579 | cond_resched(); | |
580 | goto again; | |
581 | } | |
582 | EXPORT_SYMBOL(clear_extent_bit); | |
583 | ||
584 | static int wait_on_state(struct extent_map_tree *tree, | |
585 | struct extent_state *state) | |
586 | { | |
587 | DEFINE_WAIT(wait); | |
588 | prepare_to_wait(&state->wq, &wait, TASK_UNINTERRUPTIBLE); | |
589 | read_unlock_irq(&tree->lock); | |
590 | schedule(); | |
591 | read_lock_irq(&tree->lock); | |
592 | finish_wait(&state->wq, &wait); | |
593 | return 0; | |
594 | } | |
595 | ||
596 | /* | |
597 | * waits for one or more bits to clear on a range in the state tree. | |
598 | * The range [start, end] is inclusive. | |
599 | * The tree lock is taken by this function | |
600 | */ | |
601 | int wait_extent_bit(struct extent_map_tree *tree, u64 start, u64 end, int bits) | |
602 | { | |
603 | struct extent_state *state; | |
604 | struct rb_node *node; | |
605 | ||
606 | read_lock_irq(&tree->lock); | |
607 | again: | |
608 | while (1) { | |
609 | /* | |
610 | * this search will find all the extents that end after | |
611 | * our range starts | |
612 | */ | |
613 | node = tree_search(&tree->state, start); | |
614 | if (!node) | |
615 | break; | |
616 | ||
617 | state = rb_entry(node, struct extent_state, rb_node); | |
618 | ||
619 | if (state->start > end) | |
620 | goto out; | |
621 | ||
622 | if (state->state & bits) { | |
623 | start = state->start; | |
624 | atomic_inc(&state->refs); | |
625 | wait_on_state(tree, state); | |
626 | free_extent_state(state); | |
627 | goto again; | |
628 | } | |
629 | start = state->end + 1; | |
630 | ||
631 | if (start > end) | |
632 | break; | |
633 | ||
634 | if (need_resched()) { | |
635 | read_unlock_irq(&tree->lock); | |
636 | cond_resched(); | |
637 | read_lock_irq(&tree->lock); | |
638 | } | |
639 | } | |
640 | out: | |
641 | read_unlock_irq(&tree->lock); | |
642 | return 0; | |
643 | } | |
644 | EXPORT_SYMBOL(wait_extent_bit); | |
645 | ||
646 | /* | |
647 | * set some bits on a range in the tree. This may require allocations | |
648 | * or sleeping, so the gfp mask is used to indicate what is allowed. | |
649 | * | |
650 | * If 'exclusive' == 1, this will fail with -EEXIST if some part of the | |
651 | * range already has the desired bits set. The start of the existing | |
652 | * range is returned in failed_start in this case. | |
653 | * | |
654 | * [start, end] is inclusive | |
655 | * This takes the tree lock. | |
656 | */ | |
657 | int set_extent_bit(struct extent_map_tree *tree, u64 start, u64 end, int bits, | |
658 | int exclusive, u64 *failed_start, gfp_t mask) | |
659 | { | |
660 | struct extent_state *state; | |
661 | struct extent_state *prealloc = NULL; | |
662 | struct rb_node *node; | |
90f1c19a | 663 | unsigned long flags; |
a52d9a80 CM |
664 | int err = 0; |
665 | int set; | |
666 | u64 last_start; | |
667 | u64 last_end; | |
668 | again: | |
669 | if (!prealloc && (mask & __GFP_WAIT)) { | |
670 | prealloc = alloc_extent_state(mask); | |
671 | if (!prealloc) | |
672 | return -ENOMEM; | |
673 | } | |
674 | ||
90f1c19a | 675 | write_lock_irqsave(&tree->lock, flags); |
a52d9a80 CM |
676 | /* |
677 | * this search will find all the extents that end after | |
678 | * our range starts. | |
679 | */ | |
680 | node = tree_search(&tree->state, start); | |
681 | if (!node) { | |
682 | err = insert_state(tree, prealloc, start, end, bits); | |
683 | prealloc = NULL; | |
684 | BUG_ON(err == -EEXIST); | |
685 | goto out; | |
686 | } | |
687 | ||
688 | state = rb_entry(node, struct extent_state, rb_node); | |
689 | last_start = state->start; | |
690 | last_end = state->end; | |
691 | ||
692 | /* | |
693 | * | ---- desired range ---- | | |
694 | * | state | | |
695 | * | |
696 | * Just lock what we found and keep going | |
697 | */ | |
698 | if (state->start == start && state->end <= end) { | |
699 | set = state->state & bits; | |
700 | if (set && exclusive) { | |
701 | *failed_start = state->start; | |
702 | err = -EEXIST; | |
703 | goto out; | |
704 | } | |
705 | state->state |= bits; | |
706 | start = state->end + 1; | |
707 | merge_state(tree, state); | |
708 | goto search_again; | |
709 | } | |
710 | ||
711 | /* | |
712 | * | ---- desired range ---- | | |
713 | * | state | | |
714 | * or | |
715 | * | ------------- state -------------- | | |
716 | * | |
717 | * We need to split the extent we found, and may flip bits on | |
718 | * second half. | |
719 | * | |
720 | * If the extent we found extends past our | |
721 | * range, we just split and search again. It'll get split | |
722 | * again the next time though. | |
723 | * | |
724 | * If the extent we found is inside our range, we set the | |
725 | * desired bit on it. | |
726 | */ | |
727 | if (state->start < start) { | |
728 | set = state->state & bits; | |
729 | if (exclusive && set) { | |
730 | *failed_start = start; | |
731 | err = -EEXIST; | |
732 | goto out; | |
733 | } | |
734 | err = split_state(tree, state, prealloc, start); | |
735 | BUG_ON(err == -EEXIST); | |
736 | prealloc = NULL; | |
737 | if (err) | |
738 | goto out; | |
739 | if (state->end <= end) { | |
740 | state->state |= bits; | |
741 | start = state->end + 1; | |
742 | merge_state(tree, state); | |
743 | } else { | |
744 | start = state->start; | |
745 | } | |
746 | goto search_again; | |
747 | } | |
a52d9a80 CM |
748 | /* |
749 | * | ---- desired range ---- | | |
750 | * | state | or | state | | |
751 | * | |
752 | * There's a hole, we need to insert something in it and | |
753 | * ignore the extent we found. | |
754 | */ | |
755 | if (state->start > start) { | |
756 | u64 this_end; | |
757 | if (end < last_start) | |
758 | this_end = end; | |
759 | else | |
760 | this_end = last_start -1; | |
761 | err = insert_state(tree, prealloc, start, this_end, | |
762 | bits); | |
763 | prealloc = NULL; | |
764 | BUG_ON(err == -EEXIST); | |
765 | if (err) | |
766 | goto out; | |
767 | start = this_end + 1; | |
768 | goto search_again; | |
769 | } | |
a8c450b2 CM |
770 | /* |
771 | * | ---- desired range ---- | | |
772 | * | state | | |
773 | * We need to split the extent, and set the bit | |
774 | * on the first half | |
775 | */ | |
776 | if (state->start <= end && state->end > end) { | |
777 | set = state->state & bits; | |
778 | if (exclusive && set) { | |
779 | *failed_start = start; | |
780 | err = -EEXIST; | |
781 | goto out; | |
782 | } | |
783 | err = split_state(tree, state, prealloc, end + 1); | |
784 | BUG_ON(err == -EEXIST); | |
785 | ||
786 | prealloc->state |= bits; | |
787 | merge_state(tree, prealloc); | |
788 | prealloc = NULL; | |
789 | goto out; | |
790 | } | |
791 | ||
a52d9a80 CM |
792 | goto search_again; |
793 | ||
794 | out: | |
90f1c19a | 795 | write_unlock_irqrestore(&tree->lock, flags); |
a52d9a80 CM |
796 | if (prealloc) |
797 | free_extent_state(prealloc); | |
798 | ||
799 | return err; | |
800 | ||
801 | search_again: | |
802 | if (start > end) | |
803 | goto out; | |
90f1c19a | 804 | write_unlock_irqrestore(&tree->lock, flags); |
a52d9a80 CM |
805 | if (mask & __GFP_WAIT) |
806 | cond_resched(); | |
807 | goto again; | |
808 | } | |
809 | EXPORT_SYMBOL(set_extent_bit); | |
810 | ||
811 | /* wrappers around set/clear extent bit */ | |
812 | int set_extent_dirty(struct extent_map_tree *tree, u64 start, u64 end, | |
813 | gfp_t mask) | |
814 | { | |
815 | return set_extent_bit(tree, start, end, EXTENT_DIRTY, 0, NULL, | |
816 | mask); | |
817 | } | |
818 | EXPORT_SYMBOL(set_extent_dirty); | |
819 | ||
96b5179d CM |
820 | int set_extent_bits(struct extent_map_tree *tree, u64 start, u64 end, |
821 | int bits, gfp_t mask) | |
822 | { | |
823 | return set_extent_bit(tree, start, end, bits, 0, NULL, | |
824 | mask); | |
825 | } | |
826 | EXPORT_SYMBOL(set_extent_bits); | |
827 | ||
828 | int clear_extent_bits(struct extent_map_tree *tree, u64 start, u64 end, | |
829 | int bits, gfp_t mask) | |
830 | { | |
831 | return clear_extent_bit(tree, start, end, bits, 0, 0, mask); | |
832 | } | |
833 | EXPORT_SYMBOL(clear_extent_bits); | |
834 | ||
b888db2b CM |
835 | int set_extent_delalloc(struct extent_map_tree *tree, u64 start, u64 end, |
836 | gfp_t mask) | |
837 | { | |
838 | return set_extent_bit(tree, start, end, | |
839 | EXTENT_DELALLOC | EXTENT_DIRTY, 0, NULL, | |
840 | mask); | |
841 | } | |
842 | EXPORT_SYMBOL(set_extent_delalloc); | |
843 | ||
a52d9a80 CM |
844 | int clear_extent_dirty(struct extent_map_tree *tree, u64 start, u64 end, |
845 | gfp_t mask) | |
846 | { | |
b888db2b CM |
847 | return clear_extent_bit(tree, start, end, |
848 | EXTENT_DIRTY | EXTENT_DELALLOC, 0, 0, mask); | |
a52d9a80 CM |
849 | } |
850 | EXPORT_SYMBOL(clear_extent_dirty); | |
851 | ||
852 | int set_extent_new(struct extent_map_tree *tree, u64 start, u64 end, | |
853 | gfp_t mask) | |
854 | { | |
855 | return set_extent_bit(tree, start, end, EXTENT_NEW, 0, NULL, | |
856 | mask); | |
857 | } | |
858 | EXPORT_SYMBOL(set_extent_new); | |
859 | ||
860 | int clear_extent_new(struct extent_map_tree *tree, u64 start, u64 end, | |
861 | gfp_t mask) | |
862 | { | |
863 | return clear_extent_bit(tree, start, end, EXTENT_NEW, 0, 0, mask); | |
864 | } | |
865 | EXPORT_SYMBOL(clear_extent_new); | |
866 | ||
867 | int set_extent_uptodate(struct extent_map_tree *tree, u64 start, u64 end, | |
868 | gfp_t mask) | |
869 | { | |
870 | return set_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, NULL, | |
871 | mask); | |
872 | } | |
873 | EXPORT_SYMBOL(set_extent_uptodate); | |
874 | ||
875 | int clear_extent_uptodate(struct extent_map_tree *tree, u64 start, u64 end, | |
876 | gfp_t mask) | |
877 | { | |
878 | return clear_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, 0, mask); | |
879 | } | |
880 | EXPORT_SYMBOL(clear_extent_uptodate); | |
881 | ||
882 | int set_extent_writeback(struct extent_map_tree *tree, u64 start, u64 end, | |
883 | gfp_t mask) | |
884 | { | |
885 | return set_extent_bit(tree, start, end, EXTENT_WRITEBACK, | |
886 | 0, NULL, mask); | |
887 | } | |
888 | EXPORT_SYMBOL(set_extent_writeback); | |
889 | ||
890 | int clear_extent_writeback(struct extent_map_tree *tree, u64 start, u64 end, | |
891 | gfp_t mask) | |
892 | { | |
893 | return clear_extent_bit(tree, start, end, EXTENT_WRITEBACK, 1, 0, mask); | |
894 | } | |
895 | EXPORT_SYMBOL(clear_extent_writeback); | |
896 | ||
897 | int wait_on_extent_writeback(struct extent_map_tree *tree, u64 start, u64 end) | |
898 | { | |
899 | return wait_extent_bit(tree, start, end, EXTENT_WRITEBACK); | |
900 | } | |
901 | EXPORT_SYMBOL(wait_on_extent_writeback); | |
902 | ||
903 | /* | |
904 | * locks a range in ascending order, waiting for any locked regions | |
905 | * it hits on the way. [start,end] are inclusive, and this will sleep. | |
906 | */ | |
907 | int lock_extent(struct extent_map_tree *tree, u64 start, u64 end, gfp_t mask) | |
908 | { | |
909 | int err; | |
910 | u64 failed_start; | |
911 | while (1) { | |
912 | err = set_extent_bit(tree, start, end, EXTENT_LOCKED, 1, | |
913 | &failed_start, mask); | |
914 | if (err == -EEXIST && (mask & __GFP_WAIT)) { | |
915 | wait_extent_bit(tree, failed_start, end, EXTENT_LOCKED); | |
916 | start = failed_start; | |
917 | } else { | |
918 | break; | |
919 | } | |
920 | WARN_ON(start > end); | |
921 | } | |
922 | return err; | |
923 | } | |
924 | EXPORT_SYMBOL(lock_extent); | |
925 | ||
926 | int unlock_extent(struct extent_map_tree *tree, u64 start, u64 end, | |
927 | gfp_t mask) | |
928 | { | |
929 | return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, mask); | |
930 | } | |
931 | EXPORT_SYMBOL(unlock_extent); | |
932 | ||
933 | /* | |
934 | * helper function to set pages and extents in the tree dirty | |
935 | */ | |
936 | int set_range_dirty(struct extent_map_tree *tree, u64 start, u64 end) | |
937 | { | |
938 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
939 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
940 | struct page *page; | |
941 | ||
942 | while (index <= end_index) { | |
943 | page = find_get_page(tree->mapping, index); | |
944 | BUG_ON(!page); | |
945 | __set_page_dirty_nobuffers(page); | |
946 | page_cache_release(page); | |
947 | index++; | |
948 | } | |
949 | set_extent_dirty(tree, start, end, GFP_NOFS); | |
950 | return 0; | |
951 | } | |
952 | EXPORT_SYMBOL(set_range_dirty); | |
953 | ||
954 | /* | |
955 | * helper function to set both pages and extents in the tree writeback | |
956 | */ | |
957 | int set_range_writeback(struct extent_map_tree *tree, u64 start, u64 end) | |
958 | { | |
959 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
960 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
961 | struct page *page; | |
962 | ||
963 | while (index <= end_index) { | |
964 | page = find_get_page(tree->mapping, index); | |
965 | BUG_ON(!page); | |
966 | set_page_writeback(page); | |
967 | page_cache_release(page); | |
968 | index++; | |
969 | } | |
970 | set_extent_writeback(tree, start, end, GFP_NOFS); | |
971 | return 0; | |
972 | } | |
973 | EXPORT_SYMBOL(set_range_writeback); | |
974 | ||
5f39d397 CM |
975 | int find_first_extent_bit(struct extent_map_tree *tree, u64 start, |
976 | u64 *start_ret, u64 *end_ret, int bits) | |
977 | { | |
978 | struct rb_node *node; | |
979 | struct extent_state *state; | |
980 | int ret = 1; | |
981 | ||
e19caa5f | 982 | read_lock_irq(&tree->lock); |
5f39d397 CM |
983 | /* |
984 | * this search will find all the extents that end after | |
985 | * our range starts. | |
986 | */ | |
987 | node = tree_search(&tree->state, start); | |
988 | if (!node || IS_ERR(node)) { | |
989 | goto out; | |
990 | } | |
991 | ||
992 | while(1) { | |
993 | state = rb_entry(node, struct extent_state, rb_node); | |
e19caa5f | 994 | if (state->end >= start && (state->state & bits)) { |
5f39d397 CM |
995 | *start_ret = state->start; |
996 | *end_ret = state->end; | |
997 | ret = 0; | |
f510cfec | 998 | break; |
5f39d397 CM |
999 | } |
1000 | node = rb_next(node); | |
1001 | if (!node) | |
1002 | break; | |
1003 | } | |
1004 | out: | |
e19caa5f | 1005 | read_unlock_irq(&tree->lock); |
5f39d397 CM |
1006 | return ret; |
1007 | } | |
1008 | EXPORT_SYMBOL(find_first_extent_bit); | |
1009 | ||
b888db2b CM |
1010 | u64 find_lock_delalloc_range(struct extent_map_tree *tree, |
1011 | u64 start, u64 lock_start, u64 *end, u64 max_bytes) | |
1012 | { | |
1013 | struct rb_node *node; | |
1014 | struct extent_state *state; | |
1015 | u64 cur_start = start; | |
1016 | u64 found = 0; | |
1017 | u64 total_bytes = 0; | |
1018 | ||
1019 | write_lock_irq(&tree->lock); | |
1020 | /* | |
1021 | * this search will find all the extents that end after | |
1022 | * our range starts. | |
1023 | */ | |
1024 | search_again: | |
1025 | node = tree_search(&tree->state, cur_start); | |
1026 | if (!node || IS_ERR(node)) { | |
1027 | goto out; | |
1028 | } | |
1029 | ||
1030 | while(1) { | |
1031 | state = rb_entry(node, struct extent_state, rb_node); | |
1032 | if (state->start != cur_start) { | |
1033 | goto out; | |
1034 | } | |
1035 | if (!(state->state & EXTENT_DELALLOC)) { | |
1036 | goto out; | |
1037 | } | |
1038 | if (state->start >= lock_start) { | |
1039 | if (state->state & EXTENT_LOCKED) { | |
1040 | DEFINE_WAIT(wait); | |
1041 | atomic_inc(&state->refs); | |
1042 | write_unlock_irq(&tree->lock); | |
1043 | schedule(); | |
1044 | write_lock_irq(&tree->lock); | |
1045 | finish_wait(&state->wq, &wait); | |
1046 | free_extent_state(state); | |
1047 | goto search_again; | |
1048 | } | |
1049 | state->state |= EXTENT_LOCKED; | |
1050 | } | |
1051 | found++; | |
1052 | *end = state->end; | |
1053 | cur_start = state->end + 1; | |
1054 | node = rb_next(node); | |
1055 | if (!node) | |
1056 | break; | |
1057 | total_bytes = state->end - state->start + 1; | |
1058 | if (total_bytes >= max_bytes) | |
1059 | break; | |
1060 | } | |
1061 | out: | |
1062 | write_unlock_irq(&tree->lock); | |
1063 | return found; | |
1064 | } | |
1065 | ||
a52d9a80 CM |
1066 | /* |
1067 | * helper function to lock both pages and extents in the tree. | |
1068 | * pages must be locked first. | |
1069 | */ | |
1070 | int lock_range(struct extent_map_tree *tree, u64 start, u64 end) | |
1071 | { | |
1072 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1073 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
1074 | struct page *page; | |
1075 | int err; | |
1076 | ||
1077 | while (index <= end_index) { | |
1078 | page = grab_cache_page(tree->mapping, index); | |
1079 | if (!page) { | |
1080 | err = -ENOMEM; | |
1081 | goto failed; | |
1082 | } | |
1083 | if (IS_ERR(page)) { | |
1084 | err = PTR_ERR(page); | |
1085 | goto failed; | |
1086 | } | |
1087 | index++; | |
1088 | } | |
1089 | lock_extent(tree, start, end, GFP_NOFS); | |
1090 | return 0; | |
1091 | ||
1092 | failed: | |
1093 | /* | |
1094 | * we failed above in getting the page at 'index', so we undo here | |
1095 | * up to but not including the page at 'index' | |
1096 | */ | |
1097 | end_index = index; | |
1098 | index = start >> PAGE_CACHE_SHIFT; | |
1099 | while (index < end_index) { | |
1100 | page = find_get_page(tree->mapping, index); | |
1101 | unlock_page(page); | |
1102 | page_cache_release(page); | |
1103 | index++; | |
1104 | } | |
1105 | return err; | |
1106 | } | |
1107 | EXPORT_SYMBOL(lock_range); | |
1108 | ||
1109 | /* | |
1110 | * helper function to unlock both pages and extents in the tree. | |
1111 | */ | |
1112 | int unlock_range(struct extent_map_tree *tree, u64 start, u64 end) | |
1113 | { | |
1114 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1115 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
1116 | struct page *page; | |
1117 | ||
1118 | while (index <= end_index) { | |
1119 | page = find_get_page(tree->mapping, index); | |
1120 | unlock_page(page); | |
1121 | page_cache_release(page); | |
1122 | index++; | |
1123 | } | |
1124 | unlock_extent(tree, start, end, GFP_NOFS); | |
1125 | return 0; | |
1126 | } | |
1127 | EXPORT_SYMBOL(unlock_range); | |
1128 | ||
07157aac CM |
1129 | int set_state_private(struct extent_map_tree *tree, u64 start, u64 private) |
1130 | { | |
1131 | struct rb_node *node; | |
1132 | struct extent_state *state; | |
1133 | int ret = 0; | |
1134 | ||
1135 | write_lock_irq(&tree->lock); | |
1136 | /* | |
1137 | * this search will find all the extents that end after | |
1138 | * our range starts. | |
1139 | */ | |
1140 | node = tree_search(&tree->state, start); | |
1141 | if (!node || IS_ERR(node)) { | |
1142 | ret = -ENOENT; | |
1143 | goto out; | |
1144 | } | |
1145 | state = rb_entry(node, struct extent_state, rb_node); | |
1146 | if (state->start != start) { | |
1147 | ret = -ENOENT; | |
1148 | goto out; | |
1149 | } | |
1150 | state->private = private; | |
1151 | out: | |
1152 | write_unlock_irq(&tree->lock); | |
1153 | return ret; | |
07157aac CM |
1154 | } |
1155 | ||
1156 | int get_state_private(struct extent_map_tree *tree, u64 start, u64 *private) | |
1157 | { | |
1158 | struct rb_node *node; | |
1159 | struct extent_state *state; | |
1160 | int ret = 0; | |
1161 | ||
1162 | read_lock_irq(&tree->lock); | |
1163 | /* | |
1164 | * this search will find all the extents that end after | |
1165 | * our range starts. | |
1166 | */ | |
1167 | node = tree_search(&tree->state, start); | |
1168 | if (!node || IS_ERR(node)) { | |
1169 | ret = -ENOENT; | |
1170 | goto out; | |
1171 | } | |
1172 | state = rb_entry(node, struct extent_state, rb_node); | |
1173 | if (state->start != start) { | |
1174 | ret = -ENOENT; | |
1175 | goto out; | |
1176 | } | |
1177 | *private = state->private; | |
1178 | out: | |
1179 | read_unlock_irq(&tree->lock); | |
1180 | return ret; | |
1181 | } | |
1182 | ||
a52d9a80 CM |
1183 | /* |
1184 | * searches a range in the state tree for a given mask. | |
1185 | * If 'filled' == 1, this returns 1 only if ever extent in the tree | |
1186 | * has the bits set. Otherwise, 1 is returned if any bit in the | |
1187 | * range is found set. | |
1188 | */ | |
1a5bc167 CM |
1189 | int test_range_bit(struct extent_map_tree *tree, u64 start, u64 end, |
1190 | int bits, int filled) | |
a52d9a80 CM |
1191 | { |
1192 | struct extent_state *state = NULL; | |
1193 | struct rb_node *node; | |
1194 | int bitset = 0; | |
1195 | ||
1196 | read_lock_irq(&tree->lock); | |
1197 | node = tree_search(&tree->state, start); | |
1198 | while (node && start <= end) { | |
1199 | state = rb_entry(node, struct extent_state, rb_node); | |
1200 | if (state->start > end) | |
1201 | break; | |
1202 | ||
1203 | if (filled && state->start > start) { | |
1204 | bitset = 0; | |
1205 | break; | |
1206 | } | |
1207 | if (state->state & bits) { | |
1208 | bitset = 1; | |
1209 | if (!filled) | |
1210 | break; | |
1211 | } else if (filled) { | |
1212 | bitset = 0; | |
1213 | break; | |
1214 | } | |
1215 | start = state->end + 1; | |
1216 | if (start > end) | |
1217 | break; | |
1218 | node = rb_next(node); | |
1219 | } | |
1220 | read_unlock_irq(&tree->lock); | |
1221 | return bitset; | |
1222 | } | |
1a5bc167 | 1223 | EXPORT_SYMBOL(test_range_bit); |
a52d9a80 CM |
1224 | |
1225 | /* | |
1226 | * helper function to set a given page up to date if all the | |
1227 | * extents in the tree for that page are up to date | |
1228 | */ | |
1229 | static int check_page_uptodate(struct extent_map_tree *tree, | |
1230 | struct page *page) | |
1231 | { | |
35ebb934 | 1232 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; |
a52d9a80 CM |
1233 | u64 end = start + PAGE_CACHE_SIZE - 1; |
1234 | if (test_range_bit(tree, start, end, EXTENT_UPTODATE, 1)) | |
1235 | SetPageUptodate(page); | |
1236 | return 0; | |
1237 | } | |
1238 | ||
1239 | /* | |
1240 | * helper function to unlock a page if all the extents in the tree | |
1241 | * for that page are unlocked | |
1242 | */ | |
1243 | static int check_page_locked(struct extent_map_tree *tree, | |
1244 | struct page *page) | |
1245 | { | |
35ebb934 | 1246 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; |
a52d9a80 CM |
1247 | u64 end = start + PAGE_CACHE_SIZE - 1; |
1248 | if (!test_range_bit(tree, start, end, EXTENT_LOCKED, 0)) | |
1249 | unlock_page(page); | |
1250 | return 0; | |
1251 | } | |
1252 | ||
1253 | /* | |
1254 | * helper function to end page writeback if all the extents | |
1255 | * in the tree for that page are done with writeback | |
1256 | */ | |
1257 | static int check_page_writeback(struct extent_map_tree *tree, | |
1258 | struct page *page) | |
1259 | { | |
35ebb934 | 1260 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; |
a52d9a80 CM |
1261 | u64 end = start + PAGE_CACHE_SIZE - 1; |
1262 | if (!test_range_bit(tree, start, end, EXTENT_WRITEBACK, 0)) | |
1263 | end_page_writeback(page); | |
1264 | return 0; | |
1265 | } | |
1266 | ||
1267 | /* lots and lots of room for performance fixes in the end_bio funcs */ | |
1268 | ||
1269 | /* | |
1270 | * after a writepage IO is done, we need to: | |
1271 | * clear the uptodate bits on error | |
1272 | * clear the writeback bits in the extent tree for this IO | |
1273 | * end_page_writeback if the page has no more pending IO | |
1274 | * | |
1275 | * Scheduling is not allowed, so the extent state tree is expected | |
1276 | * to have one and only one object corresponding to this IO. | |
1277 | */ | |
0a2118df JA |
1278 | #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23) |
1279 | static void end_bio_extent_writepage(struct bio *bio, int err) | |
1280 | #else | |
a52d9a80 CM |
1281 | static int end_bio_extent_writepage(struct bio *bio, |
1282 | unsigned int bytes_done, int err) | |
0a2118df | 1283 | #endif |
a52d9a80 CM |
1284 | { |
1285 | const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); | |
1286 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; | |
1287 | struct extent_map_tree *tree = bio->bi_private; | |
1288 | u64 start; | |
1289 | u64 end; | |
1290 | int whole_page; | |
1291 | ||
0a2118df | 1292 | #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23) |
a52d9a80 CM |
1293 | if (bio->bi_size) |
1294 | return 1; | |
0a2118df | 1295 | #endif |
a52d9a80 CM |
1296 | |
1297 | do { | |
1298 | struct page *page = bvec->bv_page; | |
35ebb934 CM |
1299 | start = ((u64)page->index << PAGE_CACHE_SHIFT) + |
1300 | bvec->bv_offset; | |
a52d9a80 CM |
1301 | end = start + bvec->bv_len - 1; |
1302 | ||
1303 | if (bvec->bv_offset == 0 && bvec->bv_len == PAGE_CACHE_SIZE) | |
1304 | whole_page = 1; | |
1305 | else | |
1306 | whole_page = 0; | |
1307 | ||
1308 | if (--bvec >= bio->bi_io_vec) | |
1309 | prefetchw(&bvec->bv_page->flags); | |
1310 | ||
1311 | if (!uptodate) { | |
1312 | clear_extent_uptodate(tree, start, end, GFP_ATOMIC); | |
1313 | ClearPageUptodate(page); | |
1314 | SetPageError(page); | |
1315 | } | |
1316 | clear_extent_writeback(tree, start, end, GFP_ATOMIC); | |
1317 | ||
1318 | if (whole_page) | |
1319 | end_page_writeback(page); | |
1320 | else | |
1321 | check_page_writeback(tree, page); | |
0e2752a7 CH |
1322 | if (tree->ops && tree->ops->writepage_end_io_hook) |
1323 | tree->ops->writepage_end_io_hook(page, start, end); | |
a52d9a80 CM |
1324 | } while (bvec >= bio->bi_io_vec); |
1325 | ||
1326 | bio_put(bio); | |
0a2118df | 1327 | #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23) |
a52d9a80 | 1328 | return 0; |
0a2118df | 1329 | #endif |
a52d9a80 CM |
1330 | } |
1331 | ||
1332 | /* | |
1333 | * after a readpage IO is done, we need to: | |
1334 | * clear the uptodate bits on error | |
1335 | * set the uptodate bits if things worked | |
1336 | * set the page up to date if all extents in the tree are uptodate | |
1337 | * clear the lock bit in the extent tree | |
1338 | * unlock the page if there are no other extents locked for it | |
1339 | * | |
1340 | * Scheduling is not allowed, so the extent state tree is expected | |
1341 | * to have one and only one object corresponding to this IO. | |
1342 | */ | |
0a2118df JA |
1343 | #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23) |
1344 | static void end_bio_extent_readpage(struct bio *bio, int err) | |
1345 | #else | |
a52d9a80 CM |
1346 | static int end_bio_extent_readpage(struct bio *bio, |
1347 | unsigned int bytes_done, int err) | |
0a2118df | 1348 | #endif |
a52d9a80 | 1349 | { |
07157aac | 1350 | int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); |
a52d9a80 CM |
1351 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; |
1352 | struct extent_map_tree *tree = bio->bi_private; | |
1353 | u64 start; | |
1354 | u64 end; | |
1355 | int whole_page; | |
07157aac | 1356 | int ret; |
a52d9a80 | 1357 | |
0a2118df | 1358 | #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23) |
a52d9a80 CM |
1359 | if (bio->bi_size) |
1360 | return 1; | |
0a2118df | 1361 | #endif |
a52d9a80 CM |
1362 | |
1363 | do { | |
1364 | struct page *page = bvec->bv_page; | |
35ebb934 CM |
1365 | start = ((u64)page->index << PAGE_CACHE_SHIFT) + |
1366 | bvec->bv_offset; | |
a52d9a80 CM |
1367 | end = start + bvec->bv_len - 1; |
1368 | ||
1369 | if (bvec->bv_offset == 0 && bvec->bv_len == PAGE_CACHE_SIZE) | |
1370 | whole_page = 1; | |
1371 | else | |
1372 | whole_page = 0; | |
1373 | ||
1374 | if (--bvec >= bio->bi_io_vec) | |
1375 | prefetchw(&bvec->bv_page->flags); | |
1376 | ||
07157aac CM |
1377 | if (uptodate && tree->ops && tree->ops->readpage_end_io_hook) { |
1378 | ret = tree->ops->readpage_end_io_hook(page, start, end); | |
1379 | if (ret) | |
1380 | uptodate = 0; | |
1381 | } | |
a52d9a80 CM |
1382 | if (uptodate) { |
1383 | set_extent_uptodate(tree, start, end, GFP_ATOMIC); | |
1384 | if (whole_page) | |
1385 | SetPageUptodate(page); | |
1386 | else | |
1387 | check_page_uptodate(tree, page); | |
1388 | } else { | |
1389 | ClearPageUptodate(page); | |
1390 | SetPageError(page); | |
1391 | } | |
1392 | ||
1393 | unlock_extent(tree, start, end, GFP_ATOMIC); | |
1394 | ||
1395 | if (whole_page) | |
1396 | unlock_page(page); | |
1397 | else | |
1398 | check_page_locked(tree, page); | |
1399 | } while (bvec >= bio->bi_io_vec); | |
1400 | ||
1401 | bio_put(bio); | |
0a2118df | 1402 | #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23) |
a52d9a80 | 1403 | return 0; |
0a2118df | 1404 | #endif |
a52d9a80 CM |
1405 | } |
1406 | ||
1407 | /* | |
1408 | * IO done from prepare_write is pretty simple, we just unlock | |
1409 | * the structs in the extent tree when done, and set the uptodate bits | |
1410 | * as appropriate. | |
1411 | */ | |
0a2118df JA |
1412 | #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23) |
1413 | static void end_bio_extent_preparewrite(struct bio *bio, int err) | |
1414 | #else | |
a52d9a80 CM |
1415 | static int end_bio_extent_preparewrite(struct bio *bio, |
1416 | unsigned int bytes_done, int err) | |
0a2118df | 1417 | #endif |
a52d9a80 CM |
1418 | { |
1419 | const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); | |
1420 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; | |
1421 | struct extent_map_tree *tree = bio->bi_private; | |
1422 | u64 start; | |
1423 | u64 end; | |
1424 | ||
0a2118df | 1425 | #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23) |
a52d9a80 CM |
1426 | if (bio->bi_size) |
1427 | return 1; | |
0a2118df | 1428 | #endif |
a52d9a80 CM |
1429 | |
1430 | do { | |
1431 | struct page *page = bvec->bv_page; | |
35ebb934 CM |
1432 | start = ((u64)page->index << PAGE_CACHE_SHIFT) + |
1433 | bvec->bv_offset; | |
a52d9a80 CM |
1434 | end = start + bvec->bv_len - 1; |
1435 | ||
1436 | if (--bvec >= bio->bi_io_vec) | |
1437 | prefetchw(&bvec->bv_page->flags); | |
1438 | ||
1439 | if (uptodate) { | |
1440 | set_extent_uptodate(tree, start, end, GFP_ATOMIC); | |
1441 | } else { | |
1442 | ClearPageUptodate(page); | |
1443 | SetPageError(page); | |
1444 | } | |
1445 | ||
1446 | unlock_extent(tree, start, end, GFP_ATOMIC); | |
1447 | ||
1448 | } while (bvec >= bio->bi_io_vec); | |
1449 | ||
1450 | bio_put(bio); | |
0a2118df | 1451 | #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23) |
a52d9a80 | 1452 | return 0; |
0a2118df | 1453 | #endif |
a52d9a80 CM |
1454 | } |
1455 | ||
1456 | static int submit_extent_page(int rw, struct extent_map_tree *tree, | |
1457 | struct page *page, sector_t sector, | |
1458 | size_t size, unsigned long offset, | |
1459 | struct block_device *bdev, | |
1460 | bio_end_io_t end_io_func) | |
1461 | { | |
1462 | struct bio *bio; | |
1463 | int ret = 0; | |
1464 | ||
1465 | bio = bio_alloc(GFP_NOIO, 1); | |
1466 | ||
1467 | bio->bi_sector = sector; | |
1468 | bio->bi_bdev = bdev; | |
1469 | bio->bi_io_vec[0].bv_page = page; | |
1470 | bio->bi_io_vec[0].bv_len = size; | |
1471 | bio->bi_io_vec[0].bv_offset = offset; | |
1472 | ||
1473 | bio->bi_vcnt = 1; | |
1474 | bio->bi_idx = 0; | |
1475 | bio->bi_size = size; | |
1476 | ||
1477 | bio->bi_end_io = end_io_func; | |
1478 | bio->bi_private = tree; | |
1479 | ||
1480 | bio_get(bio); | |
1481 | submit_bio(rw, bio); | |
1482 | ||
1483 | if (bio_flagged(bio, BIO_EOPNOTSUPP)) | |
1484 | ret = -EOPNOTSUPP; | |
1485 | ||
1486 | bio_put(bio); | |
1487 | return ret; | |
1488 | } | |
1489 | ||
b3cfa35a CH |
1490 | void set_page_extent_mapped(struct page *page) |
1491 | { | |
1492 | if (!PagePrivate(page)) { | |
1493 | SetPagePrivate(page); | |
1494 | WARN_ON(!page->mapping->a_ops->invalidatepage); | |
19c00ddc | 1495 | set_page_private(page, EXTENT_PAGE_PRIVATE); |
b3cfa35a CH |
1496 | page_cache_get(page); |
1497 | } | |
1498 | } | |
1499 | ||
a52d9a80 CM |
1500 | /* |
1501 | * basic readpage implementation. Locked extent state structs are inserted | |
1502 | * into the tree that are removed when the IO is done (by the end_io | |
1503 | * handlers) | |
1504 | */ | |
1505 | int extent_read_full_page(struct extent_map_tree *tree, struct page *page, | |
1506 | get_extent_t *get_extent) | |
1507 | { | |
1508 | struct inode *inode = page->mapping->host; | |
35ebb934 | 1509 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; |
a52d9a80 CM |
1510 | u64 page_end = start + PAGE_CACHE_SIZE - 1; |
1511 | u64 end; | |
1512 | u64 cur = start; | |
1513 | u64 extent_offset; | |
1514 | u64 last_byte = i_size_read(inode); | |
1515 | u64 block_start; | |
1516 | u64 cur_end; | |
1517 | sector_t sector; | |
1518 | struct extent_map *em; | |
1519 | struct block_device *bdev; | |
1520 | int ret; | |
1521 | int nr = 0; | |
1522 | size_t page_offset = 0; | |
1523 | size_t iosize; | |
1524 | size_t blocksize = inode->i_sb->s_blocksize; | |
1525 | ||
b3cfa35a | 1526 | set_page_extent_mapped(page); |
a52d9a80 CM |
1527 | |
1528 | end = page_end; | |
1529 | lock_extent(tree, start, end, GFP_NOFS); | |
1530 | ||
1531 | while (cur <= end) { | |
1532 | if (cur >= last_byte) { | |
1533 | iosize = PAGE_CACHE_SIZE - page_offset; | |
1534 | zero_user_page(page, page_offset, iosize, KM_USER0); | |
1535 | set_extent_uptodate(tree, cur, cur + iosize - 1, | |
1536 | GFP_NOFS); | |
1537 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); | |
1538 | break; | |
1539 | } | |
1540 | em = get_extent(inode, page, page_offset, cur, end, 0); | |
1541 | if (IS_ERR(em) || !em) { | |
1542 | SetPageError(page); | |
1543 | unlock_extent(tree, cur, end, GFP_NOFS); | |
1544 | break; | |
1545 | } | |
1546 | ||
1547 | extent_offset = cur - em->start; | |
1548 | BUG_ON(em->end < cur); | |
1549 | BUG_ON(end < cur); | |
1550 | ||
1551 | iosize = min(em->end - cur, end - cur) + 1; | |
1552 | cur_end = min(em->end, end); | |
1553 | iosize = (iosize + blocksize - 1) & ~((u64)blocksize - 1); | |
1554 | sector = (em->block_start + extent_offset) >> 9; | |
1555 | bdev = em->bdev; | |
1556 | block_start = em->block_start; | |
1557 | free_extent_map(em); | |
1558 | em = NULL; | |
1559 | ||
1560 | /* we've found a hole, just zero and go on */ | |
5f39d397 | 1561 | if (block_start == EXTENT_MAP_HOLE) { |
a52d9a80 CM |
1562 | zero_user_page(page, page_offset, iosize, KM_USER0); |
1563 | set_extent_uptodate(tree, cur, cur + iosize - 1, | |
1564 | GFP_NOFS); | |
1565 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); | |
1566 | cur = cur + iosize; | |
1567 | page_offset += iosize; | |
1568 | continue; | |
1569 | } | |
1570 | /* the get_extent function already copied into the page */ | |
1571 | if (test_range_bit(tree, cur, cur_end, EXTENT_UPTODATE, 1)) { | |
1572 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); | |
1573 | cur = cur + iosize; | |
1574 | page_offset += iosize; | |
1575 | continue; | |
1576 | } | |
1577 | ||
07157aac CM |
1578 | ret = 0; |
1579 | if (tree->ops && tree->ops->readpage_io_hook) { | |
1580 | ret = tree->ops->readpage_io_hook(page, cur, | |
1581 | cur + iosize - 1); | |
1582 | } | |
1583 | if (!ret) { | |
1584 | ret = submit_extent_page(READ, tree, page, | |
1585 | sector, iosize, page_offset, | |
1586 | bdev, end_bio_extent_readpage); | |
1587 | } | |
a52d9a80 CM |
1588 | if (ret) |
1589 | SetPageError(page); | |
1590 | cur = cur + iosize; | |
1591 | page_offset += iosize; | |
1592 | nr++; | |
1593 | } | |
1594 | if (!nr) { | |
1595 | if (!PageError(page)) | |
1596 | SetPageUptodate(page); | |
1597 | unlock_page(page); | |
1598 | } | |
1599 | return 0; | |
1600 | } | |
1601 | EXPORT_SYMBOL(extent_read_full_page); | |
1602 | ||
1603 | /* | |
1604 | * the writepage semantics are similar to regular writepage. extent | |
1605 | * records are inserted to lock ranges in the tree, and as dirty areas | |
1606 | * are found, they are marked writeback. Then the lock bits are removed | |
1607 | * and the end_io handler clears the writeback ranges | |
1608 | */ | |
1609 | int extent_write_full_page(struct extent_map_tree *tree, struct page *page, | |
1610 | get_extent_t *get_extent, | |
1611 | struct writeback_control *wbc) | |
1612 | { | |
1613 | struct inode *inode = page->mapping->host; | |
35ebb934 | 1614 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; |
a52d9a80 CM |
1615 | u64 page_end = start + PAGE_CACHE_SIZE - 1; |
1616 | u64 end; | |
1617 | u64 cur = start; | |
1618 | u64 extent_offset; | |
1619 | u64 last_byte = i_size_read(inode); | |
1620 | u64 block_start; | |
1621 | sector_t sector; | |
1622 | struct extent_map *em; | |
1623 | struct block_device *bdev; | |
1624 | int ret; | |
1625 | int nr = 0; | |
1626 | size_t page_offset = 0; | |
1627 | size_t iosize; | |
1628 | size_t blocksize; | |
1629 | loff_t i_size = i_size_read(inode); | |
1630 | unsigned long end_index = i_size >> PAGE_CACHE_SHIFT; | |
b888db2b CM |
1631 | u64 nr_delalloc; |
1632 | u64 delalloc_end; | |
a52d9a80 | 1633 | |
b888db2b | 1634 | WARN_ON(!PageLocked(page)); |
a52d9a80 CM |
1635 | if (page->index > end_index) { |
1636 | clear_extent_dirty(tree, start, page_end, GFP_NOFS); | |
1637 | unlock_page(page); | |
1638 | return 0; | |
1639 | } | |
1640 | ||
1641 | if (page->index == end_index) { | |
1642 | size_t offset = i_size & (PAGE_CACHE_SIZE - 1); | |
1643 | zero_user_page(page, offset, | |
1644 | PAGE_CACHE_SIZE - offset, KM_USER0); | |
1645 | } | |
1646 | ||
b3cfa35a | 1647 | set_page_extent_mapped(page); |
a52d9a80 | 1648 | |
a52d9a80 | 1649 | lock_extent(tree, start, page_end, GFP_NOFS); |
b888db2b CM |
1650 | nr_delalloc = find_lock_delalloc_range(tree, start, page_end + 1, |
1651 | &delalloc_end, | |
1652 | 128 * 1024 * 1024); | |
1653 | if (nr_delalloc) { | |
07157aac | 1654 | tree->ops->fill_delalloc(inode, start, delalloc_end); |
b888db2b CM |
1655 | if (delalloc_end >= page_end + 1) { |
1656 | clear_extent_bit(tree, page_end + 1, delalloc_end, | |
1657 | EXTENT_LOCKED | EXTENT_DELALLOC, | |
1658 | 1, 0, GFP_NOFS); | |
1659 | } | |
1660 | clear_extent_bit(tree, start, page_end, EXTENT_DELALLOC, | |
1661 | 0, 0, GFP_NOFS); | |
1662 | if (test_range_bit(tree, start, page_end, EXTENT_DELALLOC, 0)) { | |
1663 | printk("found delalloc bits after clear extent_bit\n"); | |
1664 | } | |
1665 | } else if (test_range_bit(tree, start, page_end, EXTENT_DELALLOC, 0)) { | |
1666 | printk("found delalloc bits after find_delalloc_range returns 0\n"); | |
1667 | } | |
1668 | ||
1669 | end = page_end; | |
1670 | if (test_range_bit(tree, start, page_end, EXTENT_DELALLOC, 0)) { | |
1671 | printk("found delalloc bits after lock_extent\n"); | |
1672 | } | |
a52d9a80 CM |
1673 | |
1674 | if (last_byte <= start) { | |
1675 | clear_extent_dirty(tree, start, page_end, GFP_NOFS); | |
1676 | goto done; | |
1677 | } | |
1678 | ||
1679 | set_extent_uptodate(tree, start, page_end, GFP_NOFS); | |
1680 | blocksize = inode->i_sb->s_blocksize; | |
1681 | ||
1682 | while (cur <= end) { | |
1683 | if (cur >= last_byte) { | |
1684 | clear_extent_dirty(tree, cur, page_end, GFP_NOFS); | |
1685 | break; | |
1686 | } | |
b888db2b | 1687 | em = get_extent(inode, page, page_offset, cur, end, 0); |
a52d9a80 CM |
1688 | if (IS_ERR(em) || !em) { |
1689 | SetPageError(page); | |
1690 | break; | |
1691 | } | |
1692 | ||
1693 | extent_offset = cur - em->start; | |
1694 | BUG_ON(em->end < cur); | |
1695 | BUG_ON(end < cur); | |
1696 | iosize = min(em->end - cur, end - cur) + 1; | |
1697 | iosize = (iosize + blocksize - 1) & ~((u64)blocksize - 1); | |
1698 | sector = (em->block_start + extent_offset) >> 9; | |
1699 | bdev = em->bdev; | |
1700 | block_start = em->block_start; | |
1701 | free_extent_map(em); | |
1702 | em = NULL; | |
1703 | ||
5f39d397 CM |
1704 | if (block_start == EXTENT_MAP_HOLE || |
1705 | block_start == EXTENT_MAP_INLINE) { | |
a52d9a80 CM |
1706 | clear_extent_dirty(tree, cur, |
1707 | cur + iosize - 1, GFP_NOFS); | |
1708 | cur = cur + iosize; | |
1709 | page_offset += iosize; | |
1710 | continue; | |
1711 | } | |
1712 | ||
1713 | /* leave this out until we have a page_mkwrite call */ | |
1714 | if (0 && !test_range_bit(tree, cur, cur + iosize - 1, | |
1715 | EXTENT_DIRTY, 0)) { | |
1716 | cur = cur + iosize; | |
1717 | page_offset += iosize; | |
1718 | continue; | |
1719 | } | |
1720 | clear_extent_dirty(tree, cur, cur + iosize - 1, GFP_NOFS); | |
b06355f0 CH |
1721 | if (tree->ops && tree->ops->writepage_io_hook) { |
1722 | ret = tree->ops->writepage_io_hook(page, cur, | |
1723 | cur + iosize - 1); | |
1724 | } else { | |
1725 | ret = 0; | |
1726 | } | |
a52d9a80 CM |
1727 | if (ret) |
1728 | SetPageError(page); | |
07157aac CM |
1729 | else { |
1730 | set_range_writeback(tree, cur, cur + iosize - 1); | |
1731 | ret = submit_extent_page(WRITE, tree, page, sector, | |
1732 | iosize, page_offset, bdev, | |
1733 | end_bio_extent_writepage); | |
1734 | if (ret) | |
1735 | SetPageError(page); | |
1736 | } | |
a52d9a80 CM |
1737 | cur = cur + iosize; |
1738 | page_offset += iosize; | |
1739 | nr++; | |
1740 | } | |
1741 | done: | |
a52d9a80 CM |
1742 | unlock_extent(tree, start, page_end, GFP_NOFS); |
1743 | unlock_page(page); | |
1744 | return 0; | |
1745 | } | |
1746 | EXPORT_SYMBOL(extent_write_full_page); | |
1747 | ||
1748 | /* | |
1749 | * basic invalidatepage code, this waits on any locked or writeback | |
1750 | * ranges corresponding to the page, and then deletes any extent state | |
1751 | * records from the tree | |
1752 | */ | |
1753 | int extent_invalidatepage(struct extent_map_tree *tree, | |
1754 | struct page *page, unsigned long offset) | |
1755 | { | |
35ebb934 | 1756 | u64 start = ((u64)page->index << PAGE_CACHE_SHIFT); |
a52d9a80 CM |
1757 | u64 end = start + PAGE_CACHE_SIZE - 1; |
1758 | size_t blocksize = page->mapping->host->i_sb->s_blocksize; | |
1759 | ||
1760 | start += (offset + blocksize -1) & ~(blocksize - 1); | |
1761 | if (start > end) | |
1762 | return 0; | |
1763 | ||
1764 | lock_extent(tree, start, end, GFP_NOFS); | |
1765 | wait_on_extent_writeback(tree, start, end); | |
2bf5a725 CM |
1766 | clear_extent_bit(tree, start, end, |
1767 | EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC, | |
a52d9a80 CM |
1768 | 1, 1, GFP_NOFS); |
1769 | return 0; | |
1770 | } | |
1771 | EXPORT_SYMBOL(extent_invalidatepage); | |
1772 | ||
1773 | /* | |
1774 | * simple commit_write call, set_range_dirty is used to mark both | |
1775 | * the pages and the extent records as dirty | |
1776 | */ | |
1777 | int extent_commit_write(struct extent_map_tree *tree, | |
1778 | struct inode *inode, struct page *page, | |
1779 | unsigned from, unsigned to) | |
1780 | { | |
1781 | loff_t pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to; | |
1782 | ||
b3cfa35a | 1783 | set_page_extent_mapped(page); |
a52d9a80 CM |
1784 | set_page_dirty(page); |
1785 | ||
1786 | if (pos > inode->i_size) { | |
1787 | i_size_write(inode, pos); | |
1788 | mark_inode_dirty(inode); | |
1789 | } | |
1790 | return 0; | |
1791 | } | |
1792 | EXPORT_SYMBOL(extent_commit_write); | |
1793 | ||
1794 | int extent_prepare_write(struct extent_map_tree *tree, | |
1795 | struct inode *inode, struct page *page, | |
1796 | unsigned from, unsigned to, get_extent_t *get_extent) | |
1797 | { | |
35ebb934 | 1798 | u64 page_start = (u64)page->index << PAGE_CACHE_SHIFT; |
a52d9a80 CM |
1799 | u64 page_end = page_start + PAGE_CACHE_SIZE - 1; |
1800 | u64 block_start; | |
1801 | u64 orig_block_start; | |
1802 | u64 block_end; | |
1803 | u64 cur_end; | |
1804 | struct extent_map *em; | |
1805 | unsigned blocksize = 1 << inode->i_blkbits; | |
1806 | size_t page_offset = 0; | |
1807 | size_t block_off_start; | |
1808 | size_t block_off_end; | |
1809 | int err = 0; | |
1810 | int iocount = 0; | |
1811 | int ret = 0; | |
1812 | int isnew; | |
1813 | ||
b3cfa35a CH |
1814 | set_page_extent_mapped(page); |
1815 | ||
a52d9a80 CM |
1816 | block_start = (page_start + from) & ~((u64)blocksize - 1); |
1817 | block_end = (page_start + to - 1) | (blocksize - 1); | |
1818 | orig_block_start = block_start; | |
1819 | ||
1820 | lock_extent(tree, page_start, page_end, GFP_NOFS); | |
1821 | while(block_start <= block_end) { | |
1822 | em = get_extent(inode, page, page_offset, block_start, | |
1823 | block_end, 1); | |
1824 | if (IS_ERR(em) || !em) { | |
1825 | goto err; | |
1826 | } | |
1827 | cur_end = min(block_end, em->end); | |
1828 | block_off_start = block_start & (PAGE_CACHE_SIZE - 1); | |
1829 | block_off_end = block_off_start + blocksize; | |
1830 | isnew = clear_extent_new(tree, block_start, cur_end, GFP_NOFS); | |
1831 | ||
1832 | if (!PageUptodate(page) && isnew && | |
1833 | (block_off_end > to || block_off_start < from)) { | |
1834 | void *kaddr; | |
1835 | ||
1836 | kaddr = kmap_atomic(page, KM_USER0); | |
1837 | if (block_off_end > to) | |
1838 | memset(kaddr + to, 0, block_off_end - to); | |
1839 | if (block_off_start < from) | |
1840 | memset(kaddr + block_off_start, 0, | |
1841 | from - block_off_start); | |
1842 | flush_dcache_page(page); | |
1843 | kunmap_atomic(kaddr, KM_USER0); | |
1844 | } | |
1845 | if (!isnew && !PageUptodate(page) && | |
1846 | (block_off_end > to || block_off_start < from) && | |
1847 | !test_range_bit(tree, block_start, cur_end, | |
1848 | EXTENT_UPTODATE, 1)) { | |
1849 | u64 sector; | |
1850 | u64 extent_offset = block_start - em->start; | |
1851 | size_t iosize; | |
1852 | sector = (em->block_start + extent_offset) >> 9; | |
1853 | iosize = (cur_end - block_start + blocksize - 1) & | |
1854 | ~((u64)blocksize - 1); | |
1855 | /* | |
1856 | * we've already got the extent locked, but we | |
1857 | * need to split the state such that our end_bio | |
1858 | * handler can clear the lock. | |
1859 | */ | |
1860 | set_extent_bit(tree, block_start, | |
1861 | block_start + iosize - 1, | |
1862 | EXTENT_LOCKED, 0, NULL, GFP_NOFS); | |
1863 | ret = submit_extent_page(READ, tree, page, | |
1864 | sector, iosize, page_offset, em->bdev, | |
1865 | end_bio_extent_preparewrite); | |
1866 | iocount++; | |
1867 | block_start = block_start + iosize; | |
1868 | } else { | |
1869 | set_extent_uptodate(tree, block_start, cur_end, | |
1870 | GFP_NOFS); | |
1871 | unlock_extent(tree, block_start, cur_end, GFP_NOFS); | |
1872 | block_start = cur_end + 1; | |
1873 | } | |
1874 | page_offset = block_start & (PAGE_CACHE_SIZE - 1); | |
1875 | free_extent_map(em); | |
1876 | } | |
1877 | if (iocount) { | |
1878 | wait_extent_bit(tree, orig_block_start, | |
1879 | block_end, EXTENT_LOCKED); | |
1880 | } | |
1881 | check_page_uptodate(tree, page); | |
1882 | err: | |
1883 | /* FIXME, zero out newly allocated blocks on error */ | |
1884 | return err; | |
1885 | } | |
1886 | EXPORT_SYMBOL(extent_prepare_write); | |
1887 | ||
1888 | /* | |
1889 | * a helper for releasepage. As long as there are no locked extents | |
1890 | * in the range corresponding to the page, both state records and extent | |
1891 | * map records are removed | |
1892 | */ | |
1893 | int try_release_extent_mapping(struct extent_map_tree *tree, struct page *page) | |
1894 | { | |
1895 | struct extent_map *em; | |
35ebb934 | 1896 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; |
a52d9a80 CM |
1897 | u64 end = start + PAGE_CACHE_SIZE - 1; |
1898 | u64 orig_start = start; | |
b888db2b | 1899 | int ret = 1; |
a52d9a80 CM |
1900 | |
1901 | while (start <= end) { | |
1902 | em = lookup_extent_mapping(tree, start, end); | |
1903 | if (!em || IS_ERR(em)) | |
1904 | break; | |
b888db2b CM |
1905 | if (!test_range_bit(tree, em->start, em->end, |
1906 | EXTENT_LOCKED, 0)) { | |
1907 | remove_extent_mapping(tree, em); | |
1908 | /* once for the rb tree */ | |
a52d9a80 | 1909 | free_extent_map(em); |
a52d9a80 | 1910 | } |
a52d9a80 | 1911 | start = em->end + 1; |
a52d9a80 CM |
1912 | /* once for us */ |
1913 | free_extent_map(em); | |
1914 | } | |
b888db2b CM |
1915 | if (test_range_bit(tree, orig_start, end, EXTENT_LOCKED, 0)) |
1916 | ret = 0; | |
1917 | else | |
1918 | clear_extent_bit(tree, orig_start, end, EXTENT_UPTODATE, | |
1919 | 1, 1, GFP_NOFS); | |
1920 | return ret; | |
a52d9a80 CM |
1921 | } |
1922 | EXPORT_SYMBOL(try_release_extent_mapping); | |
1923 | ||
d396c6f5 CH |
1924 | sector_t extent_bmap(struct address_space *mapping, sector_t iblock, |
1925 | get_extent_t *get_extent) | |
1926 | { | |
1927 | struct inode *inode = mapping->host; | |
1928 | u64 start = iblock << inode->i_blkbits; | |
1929 | u64 end = start + (1 << inode->i_blkbits) - 1; | |
c67cda17 | 1930 | sector_t sector = 0; |
d396c6f5 CH |
1931 | struct extent_map *em; |
1932 | ||
1933 | em = get_extent(inode, NULL, 0, start, end, 0); | |
1934 | if (!em || IS_ERR(em)) | |
1935 | return 0; | |
1936 | ||
d396c6f5 | 1937 | if (em->block_start == EXTENT_MAP_INLINE || |
5f39d397 | 1938 | em->block_start == EXTENT_MAP_HOLE) |
c67cda17 | 1939 | goto out; |
d396c6f5 | 1940 | |
c67cda17 Y |
1941 | sector = (em->block_start + start - em->start) >> inode->i_blkbits; |
1942 | out: | |
1943 | free_extent_map(em); | |
1944 | return sector; | |
d396c6f5 | 1945 | } |
5f39d397 | 1946 | |
4dc11904 | 1947 | static int add_lru(struct extent_map_tree *tree, struct extent_buffer *eb) |
6d36dcd4 | 1948 | { |
4dc11904 CM |
1949 | if (list_empty(&eb->lru)) { |
1950 | extent_buffer_get(eb); | |
1951 | list_add(&eb->lru, &tree->buffer_lru); | |
1952 | tree->lru_size++; | |
1953 | if (tree->lru_size >= BUFFER_LRU_MAX) { | |
1954 | struct extent_buffer *rm; | |
1955 | rm = list_entry(tree->buffer_lru.prev, | |
1956 | struct extent_buffer, lru); | |
1957 | tree->lru_size--; | |
1958 | list_del(&rm->lru); | |
1959 | free_extent_buffer(rm); | |
1960 | } | |
1961 | } else | |
1962 | list_move(&eb->lru, &tree->buffer_lru); | |
1963 | return 0; | |
1964 | } | |
1965 | static struct extent_buffer *find_lru(struct extent_map_tree *tree, | |
1966 | u64 start, unsigned long len) | |
1967 | { | |
1968 | struct list_head *lru = &tree->buffer_lru; | |
1969 | struct list_head *cur = lru->next; | |
1970 | struct extent_buffer *eb; | |
f510cfec | 1971 | |
4dc11904 CM |
1972 | if (list_empty(lru)) |
1973 | return NULL; | |
f510cfec | 1974 | |
4dc11904 CM |
1975 | do { |
1976 | eb = list_entry(cur, struct extent_buffer, lru); | |
1977 | if (eb->start == start && eb->len == len) { | |
1978 | extent_buffer_get(eb); | |
1979 | return eb; | |
1980 | } | |
1981 | cur = cur->next; | |
1982 | } while (cur != lru); | |
1983 | return NULL; | |
6d36dcd4 CM |
1984 | } |
1985 | ||
4dc11904 | 1986 | static inline unsigned long num_extent_pages(u64 start, u64 len) |
6d36dcd4 | 1987 | { |
4dc11904 CM |
1988 | return ((start + len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT) - |
1989 | (start >> PAGE_CACHE_SHIFT); | |
6d36dcd4 CM |
1990 | } |
1991 | ||
4dc11904 CM |
1992 | static inline struct page *extent_buffer_page(struct extent_buffer *eb, |
1993 | unsigned long i) | |
6d36dcd4 CM |
1994 | { |
1995 | struct page *p; | |
3685f791 | 1996 | struct address_space *mapping; |
db94535d | 1997 | |
4dc11904 | 1998 | if (i == 0) |
810191ff | 1999 | return eb->first_page; |
6d36dcd4 | 2000 | i += eb->start >> PAGE_CACHE_SHIFT; |
3685f791 CM |
2001 | mapping = eb->first_page->mapping; |
2002 | read_lock_irq(&mapping->tree_lock); | |
2003 | p = radix_tree_lookup(&mapping->page_tree, i); | |
2004 | read_unlock_irq(&mapping->tree_lock); | |
6d36dcd4 CM |
2005 | return p; |
2006 | } | |
2007 | ||
4dc11904 CM |
2008 | static struct extent_buffer *__alloc_extent_buffer(struct extent_map_tree *tree, |
2009 | u64 start, | |
2010 | unsigned long len, | |
2011 | gfp_t mask) | |
db94535d | 2012 | { |
4dc11904 CM |
2013 | struct extent_buffer *eb = NULL; |
2014 | ||
2015 | spin_lock(&tree->lru_lock); | |
2016 | eb = find_lru(tree, start, len); | |
19c00ddc | 2017 | if (eb) { |
4dc11904 | 2018 | goto lru_add; |
19c00ddc | 2019 | } |
4dc11904 CM |
2020 | spin_unlock(&tree->lru_lock); |
2021 | ||
2022 | if (eb) { | |
2023 | memset(eb, 0, sizeof(*eb)); | |
2024 | } else { | |
2025 | eb = kmem_cache_zalloc(extent_buffer_cache, mask); | |
2026 | } | |
2027 | INIT_LIST_HEAD(&eb->lru); | |
2028 | eb->start = start; | |
2029 | eb->len = len; | |
2030 | atomic_set(&eb->refs, 1); | |
2031 | ||
2032 | spin_lock(&tree->lru_lock); | |
2033 | lru_add: | |
2034 | add_lru(tree, eb); | |
2035 | spin_unlock(&tree->lru_lock); | |
2036 | return eb; | |
2037 | } | |
2038 | ||
2039 | static void __free_extent_buffer(struct extent_buffer *eb) | |
2040 | { | |
2041 | kmem_cache_free(extent_buffer_cache, eb); | |
db94535d | 2042 | } |
4dc11904 | 2043 | |
5f39d397 CM |
2044 | struct extent_buffer *alloc_extent_buffer(struct extent_map_tree *tree, |
2045 | u64 start, unsigned long len, | |
19c00ddc | 2046 | struct page *page0, |
5f39d397 CM |
2047 | gfp_t mask) |
2048 | { | |
db94535d | 2049 | unsigned long num_pages = num_extent_pages(start, len); |
5f39d397 CM |
2050 | unsigned long i; |
2051 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
2052 | struct extent_buffer *eb; | |
2053 | struct page *p; | |
2054 | struct address_space *mapping = tree->mapping; | |
65555a06 | 2055 | int uptodate = 1; |
5f39d397 | 2056 | |
4dc11904 | 2057 | eb = __alloc_extent_buffer(tree, start, len, mask); |
5f39d397 CM |
2058 | if (!eb || IS_ERR(eb)) |
2059 | return NULL; | |
2060 | ||
4dc11904 CM |
2061 | if (eb->flags & EXTENT_BUFFER_FILLED) |
2062 | return eb; | |
5f39d397 | 2063 | |
19c00ddc CM |
2064 | if (page0) { |
2065 | eb->first_page = page0; | |
2066 | i = 1; | |
2067 | index++; | |
2068 | page_cache_get(page0); | |
ff79f819 | 2069 | mark_page_accessed(page0); |
19c00ddc CM |
2070 | set_page_extent_mapped(page0); |
2071 | set_page_private(page0, EXTENT_PAGE_PRIVATE_FIRST_PAGE | | |
2072 | len << 2); | |
2073 | } else { | |
2074 | i = 0; | |
2075 | } | |
2076 | for (; i < num_pages; i++, index++) { | |
5f39d397 | 2077 | p = find_or_create_page(mapping, index, mask | __GFP_HIGHMEM); |
6d36dcd4 | 2078 | if (!p) { |
db94535d | 2079 | WARN_ON(1); |
6d36dcd4 CM |
2080 | /* make sure the free only frees the pages we've |
2081 | * grabbed a reference on | |
2082 | */ | |
2083 | eb->len = i << PAGE_CACHE_SHIFT; | |
2084 | eb->start &= ~((u64)PAGE_CACHE_SIZE - 1); | |
5f39d397 | 2085 | goto fail; |
6d36dcd4 | 2086 | } |
f510cfec | 2087 | set_page_extent_mapped(p); |
ff79f819 | 2088 | mark_page_accessed(p); |
19c00ddc | 2089 | if (i == 0) { |
810191ff | 2090 | eb->first_page = p; |
19c00ddc CM |
2091 | set_page_private(p, EXTENT_PAGE_PRIVATE_FIRST_PAGE | |
2092 | len << 2); | |
2093 | } else { | |
2094 | set_page_private(p, EXTENT_PAGE_PRIVATE); | |
2095 | } | |
5f39d397 CM |
2096 | if (!PageUptodate(p)) |
2097 | uptodate = 0; | |
2098 | unlock_page(p); | |
2099 | } | |
2100 | if (uptodate) | |
2101 | eb->flags |= EXTENT_UPTODATE; | |
4dc11904 | 2102 | eb->flags |= EXTENT_BUFFER_FILLED; |
5f39d397 CM |
2103 | return eb; |
2104 | fail: | |
2105 | free_extent_buffer(eb); | |
2106 | return NULL; | |
2107 | } | |
2108 | EXPORT_SYMBOL(alloc_extent_buffer); | |
2109 | ||
2110 | struct extent_buffer *find_extent_buffer(struct extent_map_tree *tree, | |
2111 | u64 start, unsigned long len, | |
2112 | gfp_t mask) | |
2113 | { | |
db94535d | 2114 | unsigned long num_pages = num_extent_pages(start, len); |
19c00ddc | 2115 | unsigned long i; unsigned long index = start >> PAGE_CACHE_SHIFT; |
5f39d397 CM |
2116 | struct extent_buffer *eb; |
2117 | struct page *p; | |
2118 | struct address_space *mapping = tree->mapping; | |
14048ed0 | 2119 | int uptodate = 1; |
5f39d397 | 2120 | |
4dc11904 | 2121 | eb = __alloc_extent_buffer(tree, start, len, mask); |
5f39d397 CM |
2122 | if (!eb || IS_ERR(eb)) |
2123 | return NULL; | |
2124 | ||
4dc11904 CM |
2125 | if (eb->flags & EXTENT_BUFFER_FILLED) |
2126 | return eb; | |
5f39d397 CM |
2127 | |
2128 | for (i = 0; i < num_pages; i++, index++) { | |
14048ed0 | 2129 | p = find_lock_page(mapping, index); |
6d36dcd4 CM |
2130 | if (!p) { |
2131 | /* make sure the free only frees the pages we've | |
2132 | * grabbed a reference on | |
2133 | */ | |
2134 | eb->len = i << PAGE_CACHE_SHIFT; | |
2135 | eb->start &= ~((u64)PAGE_CACHE_SIZE - 1); | |
5f39d397 | 2136 | goto fail; |
6d36dcd4 | 2137 | } |
f510cfec | 2138 | set_page_extent_mapped(p); |
ff79f819 | 2139 | mark_page_accessed(p); |
19c00ddc CM |
2140 | |
2141 | if (i == 0) { | |
810191ff | 2142 | eb->first_page = p; |
19c00ddc CM |
2143 | set_page_private(p, EXTENT_PAGE_PRIVATE_FIRST_PAGE | |
2144 | len << 2); | |
2145 | } else { | |
2146 | set_page_private(p, EXTENT_PAGE_PRIVATE); | |
2147 | } | |
2148 | ||
14048ed0 CM |
2149 | if (!PageUptodate(p)) |
2150 | uptodate = 0; | |
2151 | unlock_page(p); | |
5f39d397 | 2152 | } |
14048ed0 CM |
2153 | if (uptodate) |
2154 | eb->flags |= EXTENT_UPTODATE; | |
4dc11904 | 2155 | eb->flags |= EXTENT_BUFFER_FILLED; |
5f39d397 CM |
2156 | return eb; |
2157 | fail: | |
2158 | free_extent_buffer(eb); | |
2159 | return NULL; | |
2160 | } | |
2161 | EXPORT_SYMBOL(find_extent_buffer); | |
2162 | ||
2163 | void free_extent_buffer(struct extent_buffer *eb) | |
2164 | { | |
2165 | unsigned long i; | |
2166 | unsigned long num_pages; | |
2167 | ||
2168 | if (!eb) | |
2169 | return; | |
2170 | ||
2171 | if (!atomic_dec_and_test(&eb->refs)) | |
2172 | return; | |
2173 | ||
db94535d | 2174 | num_pages = num_extent_pages(eb->start, eb->len); |
5f39d397 | 2175 | |
09e71a32 | 2176 | for (i = 0; i < num_pages; i++) { |
6d36dcd4 | 2177 | page_cache_release(extent_buffer_page(eb, i)); |
5f39d397 | 2178 | } |
6d36dcd4 | 2179 | __free_extent_buffer(eb); |
5f39d397 CM |
2180 | } |
2181 | EXPORT_SYMBOL(free_extent_buffer); | |
2182 | ||
2183 | int clear_extent_buffer_dirty(struct extent_map_tree *tree, | |
2184 | struct extent_buffer *eb) | |
2185 | { | |
2186 | int set; | |
2187 | unsigned long i; | |
2188 | unsigned long num_pages; | |
2189 | struct page *page; | |
2190 | ||
2191 | u64 start = eb->start; | |
2192 | u64 end = start + eb->len - 1; | |
2193 | ||
2194 | set = clear_extent_dirty(tree, start, end, GFP_NOFS); | |
db94535d | 2195 | num_pages = num_extent_pages(eb->start, eb->len); |
5f39d397 CM |
2196 | |
2197 | for (i = 0; i < num_pages; i++) { | |
6d36dcd4 | 2198 | page = extent_buffer_page(eb, i); |
5f39d397 CM |
2199 | lock_page(page); |
2200 | /* | |
2201 | * if we're on the last page or the first page and the | |
2202 | * block isn't aligned on a page boundary, do extra checks | |
2203 | * to make sure we don't clean page that is partially dirty | |
2204 | */ | |
2205 | if ((i == 0 && (eb->start & (PAGE_CACHE_SIZE - 1))) || | |
2206 | ((i == num_pages - 1) && | |
65555a06 | 2207 | ((eb->start + eb->len) & (PAGE_CACHE_SIZE - 1)))) { |
35ebb934 | 2208 | start = (u64)page->index << PAGE_CACHE_SHIFT; |
5f39d397 CM |
2209 | end = start + PAGE_CACHE_SIZE - 1; |
2210 | if (test_range_bit(tree, start, end, | |
2211 | EXTENT_DIRTY, 0)) { | |
2212 | unlock_page(page); | |
2213 | continue; | |
2214 | } | |
2215 | } | |
2216 | clear_page_dirty_for_io(page); | |
2217 | unlock_page(page); | |
2218 | } | |
2219 | return 0; | |
2220 | } | |
2221 | EXPORT_SYMBOL(clear_extent_buffer_dirty); | |
2222 | ||
2223 | int wait_on_extent_buffer_writeback(struct extent_map_tree *tree, | |
2224 | struct extent_buffer *eb) | |
2225 | { | |
2226 | return wait_on_extent_writeback(tree, eb->start, | |
2227 | eb->start + eb->len - 1); | |
2228 | } | |
2229 | EXPORT_SYMBOL(wait_on_extent_buffer_writeback); | |
2230 | ||
2231 | int set_extent_buffer_dirty(struct extent_map_tree *tree, | |
2232 | struct extent_buffer *eb) | |
2233 | { | |
810191ff CM |
2234 | unsigned long i; |
2235 | unsigned long num_pages; | |
2236 | ||
2237 | num_pages = num_extent_pages(eb->start, eb->len); | |
2238 | for (i = 0; i < num_pages; i++) { | |
19c00ddc CM |
2239 | struct page *page = extent_buffer_page(eb, i); |
2240 | /* writepage may need to do something special for the | |
2241 | * first page, we have to make sure page->private is | |
2242 | * properly set. releasepage may drop page->private | |
2243 | * on us if the page isn't already dirty. | |
2244 | */ | |
2245 | if (i == 0) { | |
2246 | lock_page(page); | |
2247 | set_page_private(page, | |
2248 | EXTENT_PAGE_PRIVATE_FIRST_PAGE | | |
2249 | eb->len << 2); | |
2250 | } | |
810191ff | 2251 | __set_page_dirty_nobuffers(extent_buffer_page(eb, i)); |
19c00ddc CM |
2252 | if (i == 0) |
2253 | unlock_page(page); | |
810191ff CM |
2254 | } |
2255 | return set_extent_dirty(tree, eb->start, | |
2256 | eb->start + eb->len - 1, GFP_NOFS); | |
5f39d397 CM |
2257 | } |
2258 | EXPORT_SYMBOL(set_extent_buffer_dirty); | |
2259 | ||
2260 | int set_extent_buffer_uptodate(struct extent_map_tree *tree, | |
2261 | struct extent_buffer *eb) | |
2262 | { | |
2263 | unsigned long i; | |
2264 | struct page *page; | |
2265 | unsigned long num_pages; | |
2266 | ||
db94535d | 2267 | num_pages = num_extent_pages(eb->start, eb->len); |
5f39d397 CM |
2268 | |
2269 | set_extent_uptodate(tree, eb->start, eb->start + eb->len - 1, | |
2270 | GFP_NOFS); | |
2271 | for (i = 0; i < num_pages; i++) { | |
6d36dcd4 | 2272 | page = extent_buffer_page(eb, i); |
5f39d397 CM |
2273 | if ((i == 0 && (eb->start & (PAGE_CACHE_SIZE - 1))) || |
2274 | ((i == num_pages - 1) && | |
65555a06 | 2275 | ((eb->start + eb->len) & (PAGE_CACHE_SIZE - 1)))) { |
5f39d397 CM |
2276 | check_page_uptodate(tree, page); |
2277 | continue; | |
2278 | } | |
2279 | SetPageUptodate(page); | |
2280 | } | |
2281 | return 0; | |
2282 | } | |
2283 | EXPORT_SYMBOL(set_extent_buffer_uptodate); | |
2284 | ||
2285 | int extent_buffer_uptodate(struct extent_map_tree *tree, | |
2286 | struct extent_buffer *eb) | |
2287 | { | |
2288 | if (eb->flags & EXTENT_UPTODATE) | |
2289 | return 1; | |
2290 | return test_range_bit(tree, eb->start, eb->start + eb->len - 1, | |
2291 | EXTENT_UPTODATE, 1); | |
2292 | } | |
2293 | EXPORT_SYMBOL(extent_buffer_uptodate); | |
2294 | ||
2295 | int read_extent_buffer_pages(struct extent_map_tree *tree, | |
19c00ddc CM |
2296 | struct extent_buffer *eb, |
2297 | u64 start, | |
2298 | int wait) | |
5f39d397 CM |
2299 | { |
2300 | unsigned long i; | |
19c00ddc | 2301 | unsigned long start_i; |
5f39d397 CM |
2302 | struct page *page; |
2303 | int err; | |
2304 | int ret = 0; | |
2305 | unsigned long num_pages; | |
2306 | ||
2307 | if (eb->flags & EXTENT_UPTODATE) | |
2308 | return 0; | |
2309 | ||
14048ed0 | 2310 | if (0 && test_range_bit(tree, eb->start, eb->start + eb->len - 1, |
5f39d397 CM |
2311 | EXTENT_UPTODATE, 1)) { |
2312 | return 0; | |
2313 | } | |
19c00ddc CM |
2314 | if (start) { |
2315 | WARN_ON(start < eb->start); | |
2316 | start_i = (start >> PAGE_CACHE_SHIFT) - | |
2317 | (eb->start >> PAGE_CACHE_SHIFT); | |
2318 | } else { | |
2319 | start_i = 0; | |
2320 | } | |
5f39d397 | 2321 | |
db94535d | 2322 | num_pages = num_extent_pages(eb->start, eb->len); |
19c00ddc | 2323 | for (i = start_i; i < num_pages; i++) { |
6d36dcd4 | 2324 | page = extent_buffer_page(eb, i); |
5f39d397 CM |
2325 | if (PageUptodate(page)) { |
2326 | continue; | |
2327 | } | |
2328 | if (!wait) { | |
2329 | if (TestSetPageLocked(page)) { | |
2330 | continue; | |
2331 | } | |
2332 | } else { | |
2333 | lock_page(page); | |
2334 | } | |
2335 | if (!PageUptodate(page)) { | |
2336 | err = page->mapping->a_ops->readpage(NULL, page); | |
2337 | if (err) { | |
2338 | ret = err; | |
2339 | } | |
2340 | } else { | |
2341 | unlock_page(page); | |
2342 | } | |
2343 | } | |
2344 | ||
2345 | if (ret || !wait) { | |
2346 | return ret; | |
2347 | } | |
2348 | ||
19c00ddc | 2349 | for (i = start_i; i < num_pages; i++) { |
6d36dcd4 | 2350 | page = extent_buffer_page(eb, i); |
5f39d397 CM |
2351 | wait_on_page_locked(page); |
2352 | if (!PageUptodate(page)) { | |
2353 | ret = -EIO; | |
2354 | } | |
2355 | } | |
4dc11904 CM |
2356 | if (!ret) |
2357 | eb->flags |= EXTENT_UPTODATE; | |
5f39d397 CM |
2358 | return ret; |
2359 | } | |
2360 | EXPORT_SYMBOL(read_extent_buffer_pages); | |
2361 | ||
2362 | void read_extent_buffer(struct extent_buffer *eb, void *dstv, | |
2363 | unsigned long start, | |
2364 | unsigned long len) | |
2365 | { | |
2366 | size_t cur; | |
2367 | size_t offset; | |
2368 | struct page *page; | |
2369 | char *kaddr; | |
2370 | char *dst = (char *)dstv; | |
2371 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
2372 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
14048ed0 | 2373 | unsigned long num_pages = num_extent_pages(eb->start, eb->len); |
5f39d397 CM |
2374 | |
2375 | WARN_ON(start > eb->len); | |
2376 | WARN_ON(start + len > eb->start + eb->len); | |
2377 | ||
3685f791 | 2378 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); |
5f39d397 CM |
2379 | |
2380 | while(len > 0) { | |
6d36dcd4 | 2381 | page = extent_buffer_page(eb, i); |
14048ed0 CM |
2382 | if (!PageUptodate(page)) { |
2383 | printk("page %lu not up to date i %lu, total %lu, len %lu\n", page->index, i, num_pages, eb->len); | |
2384 | WARN_ON(1); | |
2385 | } | |
5f39d397 CM |
2386 | WARN_ON(!PageUptodate(page)); |
2387 | ||
2388 | cur = min(len, (PAGE_CACHE_SIZE - offset)); | |
59d169e2 | 2389 | kaddr = kmap_atomic(page, KM_USER1); |
5f39d397 | 2390 | memcpy(dst, kaddr + offset, cur); |
59d169e2 | 2391 | kunmap_atomic(kaddr, KM_USER1); |
5f39d397 CM |
2392 | |
2393 | dst += cur; | |
2394 | len -= cur; | |
2395 | offset = 0; | |
2396 | i++; | |
5f39d397 CM |
2397 | } |
2398 | } | |
2399 | EXPORT_SYMBOL(read_extent_buffer); | |
2400 | ||
19c00ddc | 2401 | int map_private_extent_buffer(struct extent_buffer *eb, unsigned long start, |
db94535d CM |
2402 | unsigned long min_len, char **token, char **map, |
2403 | unsigned long *map_start, | |
2404 | unsigned long *map_len, int km) | |
5f39d397 | 2405 | { |
479965d6 | 2406 | size_t offset = start & (PAGE_CACHE_SIZE - 1); |
5f39d397 | 2407 | char *kaddr; |
db94535d | 2408 | struct page *p; |
5f39d397 CM |
2409 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); |
2410 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
65555a06 | 2411 | unsigned long end_i = (start_offset + start + min_len - 1) >> |
810191ff | 2412 | PAGE_CACHE_SHIFT; |
479965d6 CM |
2413 | |
2414 | if (i != end_i) | |
2415 | return -EINVAL; | |
5f39d397 | 2416 | |
5f39d397 CM |
2417 | if (i == 0) { |
2418 | offset = start_offset; | |
2419 | *map_start = 0; | |
2420 | } else { | |
db94535d | 2421 | offset = 0; |
479965d6 | 2422 | *map_start = (i << PAGE_CACHE_SHIFT) - start_offset; |
5f39d397 | 2423 | } |
65555a06 | 2424 | if (start + min_len > eb->len) { |
19c00ddc CM |
2425 | printk("bad mapping eb start %Lu len %lu, wanted %lu %lu\n", eb->start, eb->len, start, min_len); |
2426 | WARN_ON(1); | |
2427 | } | |
5f39d397 | 2428 | |
db94535d CM |
2429 | p = extent_buffer_page(eb, i); |
2430 | WARN_ON(!PageUptodate(p)); | |
2431 | kaddr = kmap_atomic(p, km); | |
5f39d397 CM |
2432 | *token = kaddr; |
2433 | *map = kaddr + offset; | |
2434 | *map_len = PAGE_CACHE_SIZE - offset; | |
2435 | return 0; | |
2436 | } | |
19c00ddc | 2437 | EXPORT_SYMBOL(map_private_extent_buffer); |
db94535d CM |
2438 | |
2439 | int map_extent_buffer(struct extent_buffer *eb, unsigned long start, | |
2440 | unsigned long min_len, | |
2441 | char **token, char **map, | |
2442 | unsigned long *map_start, | |
2443 | unsigned long *map_len, int km) | |
2444 | { | |
2445 | int err; | |
2446 | int save = 0; | |
2447 | if (eb->map_token) { | |
db94535d CM |
2448 | unmap_extent_buffer(eb, eb->map_token, km); |
2449 | eb->map_token = NULL; | |
2450 | save = 1; | |
2451 | } | |
19c00ddc CM |
2452 | err = map_private_extent_buffer(eb, start, min_len, token, map, |
2453 | map_start, map_len, km); | |
db94535d CM |
2454 | if (!err && save) { |
2455 | eb->map_token = *token; | |
2456 | eb->kaddr = *map; | |
2457 | eb->map_start = *map_start; | |
2458 | eb->map_len = *map_len; | |
2459 | } | |
2460 | return err; | |
2461 | } | |
5f39d397 CM |
2462 | EXPORT_SYMBOL(map_extent_buffer); |
2463 | ||
2464 | void unmap_extent_buffer(struct extent_buffer *eb, char *token, int km) | |
2465 | { | |
ae5252bd | 2466 | kunmap_atomic(token, km); |
5f39d397 CM |
2467 | } |
2468 | EXPORT_SYMBOL(unmap_extent_buffer); | |
2469 | ||
2470 | int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv, | |
2471 | unsigned long start, | |
2472 | unsigned long len) | |
2473 | { | |
2474 | size_t cur; | |
2475 | size_t offset; | |
2476 | struct page *page; | |
2477 | char *kaddr; | |
2478 | char *ptr = (char *)ptrv; | |
2479 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
2480 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
2481 | int ret = 0; | |
2482 | ||
2483 | WARN_ON(start > eb->len); | |
2484 | WARN_ON(start + len > eb->start + eb->len); | |
2485 | ||
3685f791 | 2486 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); |
5f39d397 CM |
2487 | |
2488 | while(len > 0) { | |
6d36dcd4 | 2489 | page = extent_buffer_page(eb, i); |
5f39d397 CM |
2490 | WARN_ON(!PageUptodate(page)); |
2491 | ||
2492 | cur = min(len, (PAGE_CACHE_SIZE - offset)); | |
2493 | ||
ae5252bd | 2494 | kaddr = kmap_atomic(page, KM_USER0); |
5f39d397 | 2495 | ret = memcmp(ptr, kaddr + offset, cur); |
ae5252bd | 2496 | kunmap_atomic(kaddr, KM_USER0); |
5f39d397 CM |
2497 | if (ret) |
2498 | break; | |
2499 | ||
2500 | ptr += cur; | |
2501 | len -= cur; | |
2502 | offset = 0; | |
2503 | i++; | |
5f39d397 CM |
2504 | } |
2505 | return ret; | |
2506 | } | |
2507 | EXPORT_SYMBOL(memcmp_extent_buffer); | |
2508 | ||
2509 | void write_extent_buffer(struct extent_buffer *eb, const void *srcv, | |
2510 | unsigned long start, unsigned long len) | |
2511 | { | |
2512 | size_t cur; | |
2513 | size_t offset; | |
2514 | struct page *page; | |
2515 | char *kaddr; | |
2516 | char *src = (char *)srcv; | |
2517 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
2518 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
2519 | ||
2520 | WARN_ON(start > eb->len); | |
2521 | WARN_ON(start + len > eb->start + eb->len); | |
2522 | ||
3685f791 | 2523 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); |
5f39d397 CM |
2524 | |
2525 | while(len > 0) { | |
6d36dcd4 | 2526 | page = extent_buffer_page(eb, i); |
5f39d397 CM |
2527 | WARN_ON(!PageUptodate(page)); |
2528 | ||
2529 | cur = min(len, PAGE_CACHE_SIZE - offset); | |
59d169e2 | 2530 | kaddr = kmap_atomic(page, KM_USER1); |
5f39d397 | 2531 | memcpy(kaddr + offset, src, cur); |
59d169e2 | 2532 | kunmap_atomic(kaddr, KM_USER1); |
5f39d397 CM |
2533 | |
2534 | src += cur; | |
2535 | len -= cur; | |
2536 | offset = 0; | |
2537 | i++; | |
5f39d397 CM |
2538 | } |
2539 | } | |
2540 | EXPORT_SYMBOL(write_extent_buffer); | |
2541 | ||
2542 | void memset_extent_buffer(struct extent_buffer *eb, char c, | |
2543 | unsigned long start, unsigned long len) | |
2544 | { | |
2545 | size_t cur; | |
2546 | size_t offset; | |
2547 | struct page *page; | |
2548 | char *kaddr; | |
2549 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
2550 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
2551 | ||
2552 | WARN_ON(start > eb->len); | |
2553 | WARN_ON(start + len > eb->start + eb->len); | |
2554 | ||
3685f791 | 2555 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); |
5f39d397 CM |
2556 | |
2557 | while(len > 0) { | |
6d36dcd4 | 2558 | page = extent_buffer_page(eb, i); |
5f39d397 CM |
2559 | WARN_ON(!PageUptodate(page)); |
2560 | ||
2561 | cur = min(len, PAGE_CACHE_SIZE - offset); | |
ae5252bd | 2562 | kaddr = kmap_atomic(page, KM_USER0); |
5f39d397 | 2563 | memset(kaddr + offset, c, cur); |
ae5252bd | 2564 | kunmap_atomic(kaddr, KM_USER0); |
5f39d397 CM |
2565 | |
2566 | len -= cur; | |
2567 | offset = 0; | |
2568 | i++; | |
5f39d397 CM |
2569 | } |
2570 | } | |
2571 | EXPORT_SYMBOL(memset_extent_buffer); | |
2572 | ||
2573 | void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src, | |
2574 | unsigned long dst_offset, unsigned long src_offset, | |
2575 | unsigned long len) | |
2576 | { | |
2577 | u64 dst_len = dst->len; | |
2578 | size_t cur; | |
2579 | size_t offset; | |
2580 | struct page *page; | |
2581 | char *kaddr; | |
2582 | size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); | |
2583 | unsigned long i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT; | |
2584 | ||
2585 | WARN_ON(src->len != dst_len); | |
2586 | ||
3685f791 CM |
2587 | offset = (start_offset + dst_offset) & |
2588 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
5f39d397 CM |
2589 | |
2590 | while(len > 0) { | |
6d36dcd4 | 2591 | page = extent_buffer_page(dst, i); |
5f39d397 CM |
2592 | WARN_ON(!PageUptodate(page)); |
2593 | ||
2594 | cur = min(len, (unsigned long)(PAGE_CACHE_SIZE - offset)); | |
2595 | ||
ff190c0c | 2596 | kaddr = kmap_atomic(page, KM_USER0); |
5f39d397 | 2597 | read_extent_buffer(src, kaddr + offset, src_offset, cur); |
ff190c0c | 2598 | kunmap_atomic(kaddr, KM_USER0); |
5f39d397 CM |
2599 | |
2600 | src_offset += cur; | |
2601 | len -= cur; | |
2602 | offset = 0; | |
2603 | i++; | |
2604 | } | |
2605 | } | |
2606 | EXPORT_SYMBOL(copy_extent_buffer); | |
2607 | ||
2608 | static void move_pages(struct page *dst_page, struct page *src_page, | |
2609 | unsigned long dst_off, unsigned long src_off, | |
2610 | unsigned long len) | |
2611 | { | |
ae5252bd | 2612 | char *dst_kaddr = kmap_atomic(dst_page, KM_USER0); |
5f39d397 CM |
2613 | if (dst_page == src_page) { |
2614 | memmove(dst_kaddr + dst_off, dst_kaddr + src_off, len); | |
2615 | } else { | |
ae5252bd | 2616 | char *src_kaddr = kmap_atomic(src_page, KM_USER1); |
5f39d397 CM |
2617 | char *p = dst_kaddr + dst_off + len; |
2618 | char *s = src_kaddr + src_off + len; | |
2619 | ||
2620 | while (len--) | |
2621 | *--p = *--s; | |
2622 | ||
ae5252bd | 2623 | kunmap_atomic(src_kaddr, KM_USER1); |
5f39d397 | 2624 | } |
ae5252bd | 2625 | kunmap_atomic(dst_kaddr, KM_USER0); |
5f39d397 CM |
2626 | } |
2627 | ||
2628 | static void copy_pages(struct page *dst_page, struct page *src_page, | |
2629 | unsigned long dst_off, unsigned long src_off, | |
2630 | unsigned long len) | |
2631 | { | |
ae5252bd | 2632 | char *dst_kaddr = kmap_atomic(dst_page, KM_USER0); |
5f39d397 CM |
2633 | char *src_kaddr; |
2634 | ||
2635 | if (dst_page != src_page) | |
ae5252bd | 2636 | src_kaddr = kmap_atomic(src_page, KM_USER1); |
5f39d397 CM |
2637 | else |
2638 | src_kaddr = dst_kaddr; | |
2639 | ||
2640 | memcpy(dst_kaddr + dst_off, src_kaddr + src_off, len); | |
5f39d397 CM |
2641 | kunmap_atomic(dst_kaddr, KM_USER0); |
2642 | if (dst_page != src_page) | |
2643 | kunmap_atomic(src_kaddr, KM_USER1); | |
5f39d397 CM |
2644 | } |
2645 | ||
2646 | void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, | |
2647 | unsigned long src_offset, unsigned long len) | |
2648 | { | |
2649 | size_t cur; | |
2650 | size_t dst_off_in_page; | |
2651 | size_t src_off_in_page; | |
2652 | size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); | |
2653 | unsigned long dst_i; | |
2654 | unsigned long src_i; | |
2655 | ||
2656 | if (src_offset + len > dst->len) { | |
2657 | printk("memmove bogus src_offset %lu move len %lu len %lu\n", | |
2658 | src_offset, len, dst->len); | |
2659 | BUG_ON(1); | |
2660 | } | |
2661 | if (dst_offset + len > dst->len) { | |
2662 | printk("memmove bogus dst_offset %lu move len %lu len %lu\n", | |
2663 | dst_offset, len, dst->len); | |
2664 | BUG_ON(1); | |
2665 | } | |
2666 | ||
2667 | while(len > 0) { | |
3685f791 | 2668 | dst_off_in_page = (start_offset + dst_offset) & |
5f39d397 | 2669 | ((unsigned long)PAGE_CACHE_SIZE - 1); |
3685f791 | 2670 | src_off_in_page = (start_offset + src_offset) & |
5f39d397 CM |
2671 | ((unsigned long)PAGE_CACHE_SIZE - 1); |
2672 | ||
2673 | dst_i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT; | |
2674 | src_i = (start_offset + src_offset) >> PAGE_CACHE_SHIFT; | |
2675 | ||
5f39d397 CM |
2676 | cur = min(len, (unsigned long)(PAGE_CACHE_SIZE - |
2677 | src_off_in_page)); | |
ae2f5411 JA |
2678 | cur = min_t(unsigned long, cur, |
2679 | (unsigned long)(PAGE_CACHE_SIZE - dst_off_in_page)); | |
5f39d397 | 2680 | |
6d36dcd4 CM |
2681 | copy_pages(extent_buffer_page(dst, dst_i), |
2682 | extent_buffer_page(dst, src_i), | |
5f39d397 CM |
2683 | dst_off_in_page, src_off_in_page, cur); |
2684 | ||
2685 | src_offset += cur; | |
2686 | dst_offset += cur; | |
2687 | len -= cur; | |
2688 | } | |
2689 | } | |
2690 | EXPORT_SYMBOL(memcpy_extent_buffer); | |
2691 | ||
2692 | void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, | |
2693 | unsigned long src_offset, unsigned long len) | |
2694 | { | |
2695 | size_t cur; | |
2696 | size_t dst_off_in_page; | |
2697 | size_t src_off_in_page; | |
2698 | unsigned long dst_end = dst_offset + len - 1; | |
2699 | unsigned long src_end = src_offset + len - 1; | |
2700 | size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); | |
2701 | unsigned long dst_i; | |
2702 | unsigned long src_i; | |
2703 | ||
2704 | if (src_offset + len > dst->len) { | |
2705 | printk("memmove bogus src_offset %lu move len %lu len %lu\n", | |
2706 | src_offset, len, dst->len); | |
2707 | BUG_ON(1); | |
2708 | } | |
2709 | if (dst_offset + len > dst->len) { | |
2710 | printk("memmove bogus dst_offset %lu move len %lu len %lu\n", | |
2711 | dst_offset, len, dst->len); | |
2712 | BUG_ON(1); | |
2713 | } | |
2714 | if (dst_offset < src_offset) { | |
2715 | memcpy_extent_buffer(dst, dst_offset, src_offset, len); | |
2716 | return; | |
2717 | } | |
2718 | while(len > 0) { | |
2719 | dst_i = (start_offset + dst_end) >> PAGE_CACHE_SHIFT; | |
2720 | src_i = (start_offset + src_end) >> PAGE_CACHE_SHIFT; | |
2721 | ||
3685f791 | 2722 | dst_off_in_page = (start_offset + dst_end) & |
5f39d397 | 2723 | ((unsigned long)PAGE_CACHE_SIZE - 1); |
3685f791 | 2724 | src_off_in_page = (start_offset + src_end) & |
5f39d397 | 2725 | ((unsigned long)PAGE_CACHE_SIZE - 1); |
5f39d397 | 2726 | |
ae2f5411 | 2727 | cur = min_t(unsigned long, len, src_off_in_page + 1); |
5f39d397 | 2728 | cur = min(cur, dst_off_in_page + 1); |
6d36dcd4 CM |
2729 | move_pages(extent_buffer_page(dst, dst_i), |
2730 | extent_buffer_page(dst, src_i), | |
5f39d397 CM |
2731 | dst_off_in_page - cur + 1, |
2732 | src_off_in_page - cur + 1, cur); | |
2733 | ||
db94535d CM |
2734 | dst_end -= cur; |
2735 | src_end -= cur; | |
5f39d397 CM |
2736 | len -= cur; |
2737 | } | |
2738 | } | |
2739 | EXPORT_SYMBOL(memmove_extent_buffer); |