]>
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> |
b293f02e | 13 | #include <linux/writeback.h> |
3ab2fb5a | 14 | #include <linux/pagevec.h> |
a52d9a80 CM |
15 | #include "extent_map.h" |
16 | ||
86479a04 CM |
17 | /* temporary define until extent_map moves out of btrfs */ |
18 | struct kmem_cache *btrfs_cache_create(const char *name, size_t size, | |
19 | unsigned long extra_flags, | |
20 | void (*ctor)(void *, struct kmem_cache *, | |
21 | unsigned long)); | |
22 | ||
a52d9a80 CM |
23 | static struct kmem_cache *extent_map_cache; |
24 | static struct kmem_cache *extent_state_cache; | |
6d36dcd4 | 25 | static struct kmem_cache *extent_buffer_cache; |
f510cfec | 26 | |
f510cfec CM |
27 | static LIST_HEAD(buffers); |
28 | static LIST_HEAD(states); | |
29 | ||
f510cfec | 30 | static spinlock_t state_lock = SPIN_LOCK_UNLOCKED; |
4dc11904 | 31 | #define BUFFER_LRU_MAX 64 |
a52d9a80 CM |
32 | |
33 | struct tree_entry { | |
34 | u64 start; | |
35 | u64 end; | |
36 | int in_tree; | |
37 | struct rb_node rb_node; | |
38 | }; | |
39 | ||
b293f02e CM |
40 | struct extent_page_data { |
41 | struct bio *bio; | |
42 | struct extent_map_tree *tree; | |
43 | get_extent_t *get_extent; | |
44 | }; | |
ca664626 | 45 | |
2f4cbe64 | 46 | int __init extent_map_init(void) |
a52d9a80 | 47 | { |
86479a04 | 48 | extent_map_cache = btrfs_cache_create("extent_map", |
6d36dcd4 | 49 | sizeof(struct extent_map), 0, |
a52d9a80 | 50 | NULL); |
2f4cbe64 WB |
51 | if (!extent_map_cache) |
52 | return -ENOMEM; | |
86479a04 | 53 | extent_state_cache = btrfs_cache_create("extent_state", |
6d36dcd4 | 54 | sizeof(struct extent_state), 0, |
a52d9a80 | 55 | NULL); |
2f4cbe64 WB |
56 | if (!extent_state_cache) |
57 | goto free_map_cache; | |
6d36dcd4 CM |
58 | extent_buffer_cache = btrfs_cache_create("extent_buffers", |
59 | sizeof(struct extent_buffer), 0, | |
60 | NULL); | |
2f4cbe64 WB |
61 | if (!extent_buffer_cache) |
62 | goto free_state_cache; | |
63 | return 0; | |
64 | ||
65 | free_state_cache: | |
66 | kmem_cache_destroy(extent_state_cache); | |
67 | free_map_cache: | |
68 | kmem_cache_destroy(extent_map_cache); | |
69 | return -ENOMEM; | |
a52d9a80 CM |
70 | } |
71 | ||
17636e03 | 72 | void extent_map_exit(void) |
a52d9a80 | 73 | { |
f510cfec | 74 | struct extent_state *state; |
6d36dcd4 | 75 | |
f510cfec CM |
76 | while (!list_empty(&states)) { |
77 | state = list_entry(states.next, struct extent_state, list); | |
78 | 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)); | |
79 | list_del(&state->list); | |
80 | kmem_cache_free(extent_state_cache, state); | |
81 | ||
82 | } | |
f510cfec | 83 | |
a52d9a80 CM |
84 | if (extent_map_cache) |
85 | kmem_cache_destroy(extent_map_cache); | |
86 | if (extent_state_cache) | |
87 | kmem_cache_destroy(extent_state_cache); | |
6d36dcd4 CM |
88 | if (extent_buffer_cache) |
89 | kmem_cache_destroy(extent_buffer_cache); | |
a52d9a80 CM |
90 | } |
91 | ||
92 | void extent_map_tree_init(struct extent_map_tree *tree, | |
93 | struct address_space *mapping, gfp_t mask) | |
94 | { | |
95 | tree->map.rb_node = NULL; | |
96 | tree->state.rb_node = NULL; | |
07157aac | 97 | tree->ops = NULL; |
ca664626 | 98 | tree->dirty_bytes = 0; |
a52d9a80 | 99 | rwlock_init(&tree->lock); |
4dc11904 | 100 | spin_lock_init(&tree->lru_lock); |
a52d9a80 | 101 | tree->mapping = mapping; |
4dc11904 CM |
102 | INIT_LIST_HEAD(&tree->buffer_lru); |
103 | tree->lru_size = 0; | |
a52d9a80 CM |
104 | } |
105 | EXPORT_SYMBOL(extent_map_tree_init); | |
106 | ||
19c00ddc | 107 | void extent_map_tree_empty_lru(struct extent_map_tree *tree) |
4dc11904 CM |
108 | { |
109 | struct extent_buffer *eb; | |
110 | while(!list_empty(&tree->buffer_lru)) { | |
111 | eb = list_entry(tree->buffer_lru.next, struct extent_buffer, | |
112 | lru); | |
0591fb56 | 113 | list_del_init(&eb->lru); |
4dc11904 CM |
114 | free_extent_buffer(eb); |
115 | } | |
116 | } | |
19c00ddc | 117 | EXPORT_SYMBOL(extent_map_tree_empty_lru); |
4dc11904 | 118 | |
a52d9a80 CM |
119 | struct extent_map *alloc_extent_map(gfp_t mask) |
120 | { | |
121 | struct extent_map *em; | |
122 | em = kmem_cache_alloc(extent_map_cache, mask); | |
123 | if (!em || IS_ERR(em)) | |
124 | return em; | |
125 | em->in_tree = 0; | |
126 | atomic_set(&em->refs, 1); | |
127 | return em; | |
128 | } | |
129 | EXPORT_SYMBOL(alloc_extent_map); | |
130 | ||
131 | void free_extent_map(struct extent_map *em) | |
132 | { | |
2bf5a725 CM |
133 | if (!em) |
134 | return; | |
a52d9a80 CM |
135 | if (atomic_dec_and_test(&em->refs)) { |
136 | WARN_ON(em->in_tree); | |
137 | kmem_cache_free(extent_map_cache, em); | |
138 | } | |
139 | } | |
140 | EXPORT_SYMBOL(free_extent_map); | |
141 | ||
142 | ||
143 | struct extent_state *alloc_extent_state(gfp_t mask) | |
144 | { | |
145 | struct extent_state *state; | |
f510cfec CM |
146 | unsigned long flags; |
147 | ||
a52d9a80 CM |
148 | state = kmem_cache_alloc(extent_state_cache, mask); |
149 | if (!state || IS_ERR(state)) | |
150 | return state; | |
151 | state->state = 0; | |
152 | state->in_tree = 0; | |
07157aac | 153 | state->private = 0; |
f510cfec CM |
154 | |
155 | spin_lock_irqsave(&state_lock, flags); | |
156 | list_add(&state->list, &states); | |
157 | spin_unlock_irqrestore(&state_lock, flags); | |
158 | ||
a52d9a80 CM |
159 | atomic_set(&state->refs, 1); |
160 | init_waitqueue_head(&state->wq); | |
a52d9a80 CM |
161 | return state; |
162 | } | |
163 | EXPORT_SYMBOL(alloc_extent_state); | |
164 | ||
165 | void free_extent_state(struct extent_state *state) | |
166 | { | |
f510cfec | 167 | unsigned long flags; |
2bf5a725 CM |
168 | if (!state) |
169 | return; | |
a52d9a80 CM |
170 | if (atomic_dec_and_test(&state->refs)) { |
171 | WARN_ON(state->in_tree); | |
f510cfec CM |
172 | spin_lock_irqsave(&state_lock, flags); |
173 | list_del(&state->list); | |
174 | spin_unlock_irqrestore(&state_lock, flags); | |
a52d9a80 CM |
175 | kmem_cache_free(extent_state_cache, state); |
176 | } | |
177 | } | |
178 | EXPORT_SYMBOL(free_extent_state); | |
179 | ||
180 | static struct rb_node *tree_insert(struct rb_root *root, u64 offset, | |
181 | struct rb_node *node) | |
182 | { | |
183 | struct rb_node ** p = &root->rb_node; | |
184 | struct rb_node * parent = NULL; | |
185 | struct tree_entry *entry; | |
186 | ||
187 | while(*p) { | |
188 | parent = *p; | |
189 | entry = rb_entry(parent, struct tree_entry, rb_node); | |
190 | ||
191 | if (offset < entry->start) | |
192 | p = &(*p)->rb_left; | |
193 | else if (offset > entry->end) | |
194 | p = &(*p)->rb_right; | |
195 | else | |
196 | return parent; | |
197 | } | |
198 | ||
199 | entry = rb_entry(node, struct tree_entry, rb_node); | |
200 | entry->in_tree = 1; | |
201 | rb_link_node(node, parent, p); | |
202 | rb_insert_color(node, root); | |
203 | return NULL; | |
204 | } | |
205 | ||
206 | static struct rb_node *__tree_search(struct rb_root *root, u64 offset, | |
5f56406a CM |
207 | struct rb_node **prev_ret, |
208 | struct rb_node **next_ret) | |
a52d9a80 CM |
209 | { |
210 | struct rb_node * n = root->rb_node; | |
211 | struct rb_node *prev = NULL; | |
5f56406a | 212 | struct rb_node *orig_prev = NULL; |
a52d9a80 CM |
213 | struct tree_entry *entry; |
214 | struct tree_entry *prev_entry = NULL; | |
215 | ||
216 | while(n) { | |
217 | entry = rb_entry(n, struct tree_entry, rb_node); | |
218 | prev = n; | |
219 | prev_entry = entry; | |
220 | ||
221 | if (offset < entry->start) | |
222 | n = n->rb_left; | |
223 | else if (offset > entry->end) | |
224 | n = n->rb_right; | |
225 | else | |
226 | return n; | |
227 | } | |
5f56406a CM |
228 | |
229 | if (prev_ret) { | |
230 | orig_prev = prev; | |
231 | while(prev && offset > prev_entry->end) { | |
232 | prev = rb_next(prev); | |
233 | prev_entry = rb_entry(prev, struct tree_entry, rb_node); | |
234 | } | |
235 | *prev_ret = prev; | |
236 | prev = orig_prev; | |
237 | } | |
238 | ||
239 | if (next_ret) { | |
a52d9a80 | 240 | prev_entry = rb_entry(prev, struct tree_entry, rb_node); |
5f56406a CM |
241 | while(prev && offset < prev_entry->start) { |
242 | prev = rb_prev(prev); | |
243 | prev_entry = rb_entry(prev, struct tree_entry, rb_node); | |
244 | } | |
245 | *next_ret = prev; | |
a52d9a80 | 246 | } |
a52d9a80 CM |
247 | return NULL; |
248 | } | |
249 | ||
250 | static inline struct rb_node *tree_search(struct rb_root *root, u64 offset) | |
251 | { | |
252 | struct rb_node *prev; | |
253 | struct rb_node *ret; | |
5f56406a | 254 | ret = __tree_search(root, offset, &prev, NULL); |
a52d9a80 CM |
255 | if (!ret) |
256 | return prev; | |
257 | return ret; | |
258 | } | |
259 | ||
260 | static int tree_delete(struct rb_root *root, u64 offset) | |
261 | { | |
262 | struct rb_node *node; | |
263 | struct tree_entry *entry; | |
264 | ||
5f56406a | 265 | node = __tree_search(root, offset, NULL, NULL); |
a52d9a80 CM |
266 | if (!node) |
267 | return -ENOENT; | |
268 | entry = rb_entry(node, struct tree_entry, rb_node); | |
269 | entry->in_tree = 0; | |
270 | rb_erase(node, root); | |
271 | return 0; | |
272 | } | |
273 | ||
274 | /* | |
275 | * add_extent_mapping tries a simple backward merge with existing | |
276 | * mappings. The extent_map struct passed in will be inserted into | |
277 | * the tree directly (no copies made, just a reference taken). | |
278 | */ | |
279 | int add_extent_mapping(struct extent_map_tree *tree, | |
280 | struct extent_map *em) | |
281 | { | |
282 | int ret = 0; | |
283 | struct extent_map *prev = NULL; | |
284 | struct rb_node *rb; | |
285 | ||
286 | write_lock_irq(&tree->lock); | |
287 | rb = tree_insert(&tree->map, em->end, &em->rb_node); | |
288 | if (rb) { | |
289 | prev = rb_entry(rb, struct extent_map, rb_node); | |
a52d9a80 CM |
290 | ret = -EEXIST; |
291 | goto out; | |
292 | } | |
293 | atomic_inc(&em->refs); | |
294 | if (em->start != 0) { | |
295 | rb = rb_prev(&em->rb_node); | |
296 | if (rb) | |
297 | prev = rb_entry(rb, struct extent_map, rb_node); | |
298 | if (prev && prev->end + 1 == em->start && | |
5f39d397 CM |
299 | ((em->block_start == EXTENT_MAP_HOLE && |
300 | prev->block_start == EXTENT_MAP_HOLE) || | |
179e29e4 CM |
301 | (em->block_start == EXTENT_MAP_INLINE && |
302 | prev->block_start == EXTENT_MAP_INLINE) || | |
303 | (em->block_start == EXTENT_MAP_DELALLOC && | |
304 | prev->block_start == EXTENT_MAP_DELALLOC) || | |
305 | (em->block_start < EXTENT_MAP_DELALLOC - 1 && | |
306 | em->block_start == prev->block_end + 1))) { | |
a52d9a80 CM |
307 | em->start = prev->start; |
308 | em->block_start = prev->block_start; | |
309 | rb_erase(&prev->rb_node, &tree->map); | |
310 | prev->in_tree = 0; | |
311 | free_extent_map(prev); | |
312 | } | |
313 | } | |
314 | out: | |
315 | write_unlock_irq(&tree->lock); | |
316 | return ret; | |
317 | } | |
318 | EXPORT_SYMBOL(add_extent_mapping); | |
319 | ||
320 | /* | |
321 | * lookup_extent_mapping returns the first extent_map struct in the | |
322 | * tree that intersects the [start, end] (inclusive) range. There may | |
323 | * be additional objects in the tree that intersect, so check the object | |
324 | * returned carefully to make sure you don't need additional lookups. | |
325 | */ | |
326 | struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree, | |
327 | u64 start, u64 end) | |
328 | { | |
329 | struct extent_map *em; | |
330 | struct rb_node *rb_node; | |
5f56406a CM |
331 | struct rb_node *prev = NULL; |
332 | struct rb_node *next = NULL; | |
a52d9a80 CM |
333 | |
334 | read_lock_irq(&tree->lock); | |
5f56406a CM |
335 | rb_node = __tree_search(&tree->map, start, &prev, &next); |
336 | if (!rb_node && prev) { | |
337 | em = rb_entry(prev, struct extent_map, rb_node); | |
338 | if (em->start <= end && em->end >= start) | |
339 | goto found; | |
340 | } | |
341 | if (!rb_node && next) { | |
342 | em = rb_entry(next, struct extent_map, rb_node); | |
343 | if (em->start <= end && em->end >= start) | |
344 | goto found; | |
345 | } | |
a52d9a80 CM |
346 | if (!rb_node) { |
347 | em = NULL; | |
348 | goto out; | |
349 | } | |
350 | if (IS_ERR(rb_node)) { | |
351 | em = ERR_PTR(PTR_ERR(rb_node)); | |
352 | goto out; | |
353 | } | |
354 | em = rb_entry(rb_node, struct extent_map, rb_node); | |
355 | if (em->end < start || em->start > end) { | |
356 | em = NULL; | |
357 | goto out; | |
358 | } | |
5f56406a | 359 | found: |
a52d9a80 CM |
360 | atomic_inc(&em->refs); |
361 | out: | |
362 | read_unlock_irq(&tree->lock); | |
363 | return em; | |
364 | } | |
365 | EXPORT_SYMBOL(lookup_extent_mapping); | |
366 | ||
367 | /* | |
368 | * removes an extent_map struct from the tree. No reference counts are | |
369 | * dropped, and no checks are done to see if the range is in use | |
370 | */ | |
371 | int remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em) | |
372 | { | |
373 | int ret; | |
374 | ||
375 | write_lock_irq(&tree->lock); | |
376 | ret = tree_delete(&tree->map, em->end); | |
377 | write_unlock_irq(&tree->lock); | |
378 | return ret; | |
379 | } | |
380 | EXPORT_SYMBOL(remove_extent_mapping); | |
381 | ||
382 | /* | |
383 | * utility function to look for merge candidates inside a given range. | |
384 | * Any extents with matching state are merged together into a single | |
385 | * extent in the tree. Extents with EXTENT_IO in their state field | |
386 | * are not merged because the end_io handlers need to be able to do | |
387 | * operations on them without sleeping (or doing allocations/splits). | |
388 | * | |
389 | * This should be called with the tree lock held. | |
390 | */ | |
391 | static int merge_state(struct extent_map_tree *tree, | |
392 | struct extent_state *state) | |
393 | { | |
394 | struct extent_state *other; | |
395 | struct rb_node *other_node; | |
396 | ||
397 | if (state->state & EXTENT_IOBITS) | |
398 | return 0; | |
399 | ||
400 | other_node = rb_prev(&state->rb_node); | |
401 | if (other_node) { | |
402 | other = rb_entry(other_node, struct extent_state, rb_node); | |
403 | if (other->end == state->start - 1 && | |
404 | other->state == state->state) { | |
405 | state->start = other->start; | |
406 | other->in_tree = 0; | |
407 | rb_erase(&other->rb_node, &tree->state); | |
408 | free_extent_state(other); | |
409 | } | |
410 | } | |
411 | other_node = rb_next(&state->rb_node); | |
412 | if (other_node) { | |
413 | other = rb_entry(other_node, struct extent_state, rb_node); | |
414 | if (other->start == state->end + 1 && | |
415 | other->state == state->state) { | |
416 | other->start = state->start; | |
417 | state->in_tree = 0; | |
418 | rb_erase(&state->rb_node, &tree->state); | |
419 | free_extent_state(state); | |
420 | } | |
421 | } | |
422 | return 0; | |
423 | } | |
424 | ||
425 | /* | |
426 | * insert an extent_state struct into the tree. 'bits' are set on the | |
427 | * struct before it is inserted. | |
428 | * | |
429 | * This may return -EEXIST if the extent is already there, in which case the | |
430 | * state struct is freed. | |
431 | * | |
432 | * The tree lock is not taken internally. This is a utility function and | |
433 | * probably isn't what you want to call (see set/clear_extent_bit). | |
434 | */ | |
435 | static int insert_state(struct extent_map_tree *tree, | |
436 | struct extent_state *state, u64 start, u64 end, | |
437 | int bits) | |
438 | { | |
439 | struct rb_node *node; | |
440 | ||
441 | if (end < start) { | |
442 | printk("end < start %Lu %Lu\n", end, start); | |
443 | WARN_ON(1); | |
444 | } | |
ca664626 CM |
445 | if (bits & EXTENT_DIRTY) |
446 | tree->dirty_bytes += end - start + 1; | |
a52d9a80 CM |
447 | state->state |= bits; |
448 | state->start = start; | |
449 | state->end = end; | |
a52d9a80 CM |
450 | node = tree_insert(&tree->state, end, &state->rb_node); |
451 | if (node) { | |
452 | struct extent_state *found; | |
453 | found = rb_entry(node, struct extent_state, rb_node); | |
b888db2b | 454 | printk("found node %Lu %Lu on insert of %Lu %Lu\n", found->start, found->end, start, end); |
a52d9a80 CM |
455 | free_extent_state(state); |
456 | return -EEXIST; | |
457 | } | |
458 | merge_state(tree, state); | |
459 | return 0; | |
460 | } | |
461 | ||
462 | /* | |
463 | * split a given extent state struct in two, inserting the preallocated | |
464 | * struct 'prealloc' as the newly created second half. 'split' indicates an | |
465 | * offset inside 'orig' where it should be split. | |
466 | * | |
467 | * Before calling, | |
468 | * the tree has 'orig' at [orig->start, orig->end]. After calling, there | |
469 | * are two extent state structs in the tree: | |
470 | * prealloc: [orig->start, split - 1] | |
471 | * orig: [ split, orig->end ] | |
472 | * | |
473 | * The tree locks are not taken by this function. They need to be held | |
474 | * by the caller. | |
475 | */ | |
476 | static int split_state(struct extent_map_tree *tree, struct extent_state *orig, | |
477 | struct extent_state *prealloc, u64 split) | |
478 | { | |
479 | struct rb_node *node; | |
480 | prealloc->start = orig->start; | |
481 | prealloc->end = split - 1; | |
482 | prealloc->state = orig->state; | |
483 | orig->start = split; | |
f510cfec | 484 | |
a52d9a80 CM |
485 | node = tree_insert(&tree->state, prealloc->end, &prealloc->rb_node); |
486 | if (node) { | |
487 | struct extent_state *found; | |
488 | found = rb_entry(node, struct extent_state, rb_node); | |
b888db2b | 489 | printk("found node %Lu %Lu on insert of %Lu %Lu\n", found->start, found->end, prealloc->start, prealloc->end); |
a52d9a80 CM |
490 | free_extent_state(prealloc); |
491 | return -EEXIST; | |
492 | } | |
493 | return 0; | |
494 | } | |
495 | ||
496 | /* | |
497 | * utility function to clear some bits in an extent state struct. | |
498 | * it will optionally wake up any one waiting on this state (wake == 1), or | |
499 | * forcibly remove the state from the tree (delete == 1). | |
500 | * | |
501 | * If no bits are set on the state struct after clearing things, the | |
502 | * struct is freed and removed from the tree | |
503 | */ | |
504 | static int clear_state_bit(struct extent_map_tree *tree, | |
505 | struct extent_state *state, int bits, int wake, | |
506 | int delete) | |
507 | { | |
508 | int ret = state->state & bits; | |
ca664626 CM |
509 | |
510 | if ((bits & EXTENT_DIRTY) && (state->state & EXTENT_DIRTY)) { | |
511 | u64 range = state->end - state->start + 1; | |
512 | WARN_ON(range > tree->dirty_bytes); | |
513 | tree->dirty_bytes -= range; | |
514 | } | |
a52d9a80 CM |
515 | state->state &= ~bits; |
516 | if (wake) | |
517 | wake_up(&state->wq); | |
518 | if (delete || state->state == 0) { | |
519 | if (state->in_tree) { | |
520 | rb_erase(&state->rb_node, &tree->state); | |
521 | state->in_tree = 0; | |
522 | free_extent_state(state); | |
523 | } else { | |
524 | WARN_ON(1); | |
525 | } | |
526 | } else { | |
527 | merge_state(tree, state); | |
528 | } | |
529 | return ret; | |
530 | } | |
531 | ||
532 | /* | |
533 | * clear some bits on a range in the tree. This may require splitting | |
534 | * or inserting elements in the tree, so the gfp mask is used to | |
535 | * indicate which allocations or sleeping are allowed. | |
536 | * | |
537 | * pass 'wake' == 1 to kick any sleepers, and 'delete' == 1 to remove | |
538 | * the given range from the tree regardless of state (ie for truncate). | |
539 | * | |
540 | * the range [start, end] is inclusive. | |
541 | * | |
542 | * This takes the tree lock, and returns < 0 on error, > 0 if any of the | |
543 | * bits were already set, or zero if none of the bits were already set. | |
544 | */ | |
545 | int clear_extent_bit(struct extent_map_tree *tree, u64 start, u64 end, | |
546 | int bits, int wake, int delete, gfp_t mask) | |
547 | { | |
548 | struct extent_state *state; | |
549 | struct extent_state *prealloc = NULL; | |
550 | struct rb_node *node; | |
90f1c19a | 551 | unsigned long flags; |
a52d9a80 CM |
552 | int err; |
553 | int set = 0; | |
554 | ||
555 | again: | |
556 | if (!prealloc && (mask & __GFP_WAIT)) { | |
557 | prealloc = alloc_extent_state(mask); | |
558 | if (!prealloc) | |
559 | return -ENOMEM; | |
560 | } | |
561 | ||
90f1c19a | 562 | write_lock_irqsave(&tree->lock, flags); |
a52d9a80 CM |
563 | /* |
564 | * this search will find the extents that end after | |
565 | * our range starts | |
566 | */ | |
567 | node = tree_search(&tree->state, start); | |
568 | if (!node) | |
569 | goto out; | |
570 | state = rb_entry(node, struct extent_state, rb_node); | |
571 | if (state->start > end) | |
572 | goto out; | |
573 | WARN_ON(state->end < start); | |
574 | ||
575 | /* | |
576 | * | ---- desired range ---- | | |
577 | * | state | or | |
578 | * | ------------- state -------------- | | |
579 | * | |
580 | * We need to split the extent we found, and may flip | |
581 | * bits on second half. | |
582 | * | |
583 | * If the extent we found extends past our range, we | |
584 | * just split and search again. It'll get split again | |
585 | * the next time though. | |
586 | * | |
587 | * If the extent we found is inside our range, we clear | |
588 | * the desired bit on it. | |
589 | */ | |
590 | ||
591 | if (state->start < start) { | |
592 | err = split_state(tree, state, prealloc, start); | |
593 | BUG_ON(err == -EEXIST); | |
594 | prealloc = NULL; | |
595 | if (err) | |
596 | goto out; | |
597 | if (state->end <= end) { | |
598 | start = state->end + 1; | |
599 | set |= clear_state_bit(tree, state, bits, | |
600 | wake, delete); | |
601 | } else { | |
602 | start = state->start; | |
603 | } | |
604 | goto search_again; | |
605 | } | |
606 | /* | |
607 | * | ---- desired range ---- | | |
608 | * | state | | |
609 | * We need to split the extent, and clear the bit | |
610 | * on the first half | |
611 | */ | |
612 | if (state->start <= end && state->end > end) { | |
613 | err = split_state(tree, state, prealloc, end + 1); | |
614 | BUG_ON(err == -EEXIST); | |
615 | ||
616 | if (wake) | |
617 | wake_up(&state->wq); | |
618 | set |= clear_state_bit(tree, prealloc, bits, | |
619 | wake, delete); | |
620 | prealloc = NULL; | |
621 | goto out; | |
622 | } | |
623 | ||
624 | start = state->end + 1; | |
625 | set |= clear_state_bit(tree, state, bits, wake, delete); | |
626 | goto search_again; | |
627 | ||
628 | out: | |
90f1c19a | 629 | write_unlock_irqrestore(&tree->lock, flags); |
a52d9a80 CM |
630 | if (prealloc) |
631 | free_extent_state(prealloc); | |
632 | ||
633 | return set; | |
634 | ||
635 | search_again: | |
96b5179d | 636 | if (start > end) |
a52d9a80 | 637 | goto out; |
90f1c19a | 638 | write_unlock_irqrestore(&tree->lock, flags); |
a52d9a80 CM |
639 | if (mask & __GFP_WAIT) |
640 | cond_resched(); | |
641 | goto again; | |
642 | } | |
643 | EXPORT_SYMBOL(clear_extent_bit); | |
644 | ||
645 | static int wait_on_state(struct extent_map_tree *tree, | |
646 | struct extent_state *state) | |
647 | { | |
648 | DEFINE_WAIT(wait); | |
649 | prepare_to_wait(&state->wq, &wait, TASK_UNINTERRUPTIBLE); | |
650 | read_unlock_irq(&tree->lock); | |
651 | schedule(); | |
652 | read_lock_irq(&tree->lock); | |
653 | finish_wait(&state->wq, &wait); | |
654 | return 0; | |
655 | } | |
656 | ||
657 | /* | |
658 | * waits for one or more bits to clear on a range in the state tree. | |
659 | * The range [start, end] is inclusive. | |
660 | * The tree lock is taken by this function | |
661 | */ | |
662 | int wait_extent_bit(struct extent_map_tree *tree, u64 start, u64 end, int bits) | |
663 | { | |
664 | struct extent_state *state; | |
665 | struct rb_node *node; | |
666 | ||
667 | read_lock_irq(&tree->lock); | |
668 | again: | |
669 | while (1) { | |
670 | /* | |
671 | * this search will find all the extents that end after | |
672 | * our range starts | |
673 | */ | |
674 | node = tree_search(&tree->state, start); | |
675 | if (!node) | |
676 | break; | |
677 | ||
678 | state = rb_entry(node, struct extent_state, rb_node); | |
679 | ||
680 | if (state->start > end) | |
681 | goto out; | |
682 | ||
683 | if (state->state & bits) { | |
684 | start = state->start; | |
685 | atomic_inc(&state->refs); | |
686 | wait_on_state(tree, state); | |
687 | free_extent_state(state); | |
688 | goto again; | |
689 | } | |
690 | start = state->end + 1; | |
691 | ||
692 | if (start > end) | |
693 | break; | |
694 | ||
695 | if (need_resched()) { | |
696 | read_unlock_irq(&tree->lock); | |
697 | cond_resched(); | |
698 | read_lock_irq(&tree->lock); | |
699 | } | |
700 | } | |
701 | out: | |
702 | read_unlock_irq(&tree->lock); | |
703 | return 0; | |
704 | } | |
705 | EXPORT_SYMBOL(wait_extent_bit); | |
706 | ||
ca664626 CM |
707 | static void set_state_bits(struct extent_map_tree *tree, |
708 | struct extent_state *state, | |
709 | int bits) | |
710 | { | |
711 | if ((bits & EXTENT_DIRTY) && !(state->state & EXTENT_DIRTY)) { | |
712 | u64 range = state->end - state->start + 1; | |
713 | tree->dirty_bytes += range; | |
714 | } | |
715 | state->state |= bits; | |
716 | } | |
717 | ||
a52d9a80 CM |
718 | /* |
719 | * set some bits on a range in the tree. This may require allocations | |
720 | * or sleeping, so the gfp mask is used to indicate what is allowed. | |
721 | * | |
722 | * If 'exclusive' == 1, this will fail with -EEXIST if some part of the | |
723 | * range already has the desired bits set. The start of the existing | |
724 | * range is returned in failed_start in this case. | |
725 | * | |
726 | * [start, end] is inclusive | |
727 | * This takes the tree lock. | |
728 | */ | |
729 | int set_extent_bit(struct extent_map_tree *tree, u64 start, u64 end, int bits, | |
730 | int exclusive, u64 *failed_start, gfp_t mask) | |
731 | { | |
732 | struct extent_state *state; | |
733 | struct extent_state *prealloc = NULL; | |
734 | struct rb_node *node; | |
90f1c19a | 735 | unsigned long flags; |
a52d9a80 CM |
736 | int err = 0; |
737 | int set; | |
738 | u64 last_start; | |
739 | u64 last_end; | |
740 | again: | |
741 | if (!prealloc && (mask & __GFP_WAIT)) { | |
742 | prealloc = alloc_extent_state(mask); | |
743 | if (!prealloc) | |
744 | return -ENOMEM; | |
745 | } | |
746 | ||
90f1c19a | 747 | write_lock_irqsave(&tree->lock, flags); |
a52d9a80 CM |
748 | /* |
749 | * this search will find all the extents that end after | |
750 | * our range starts. | |
751 | */ | |
752 | node = tree_search(&tree->state, start); | |
753 | if (!node) { | |
754 | err = insert_state(tree, prealloc, start, end, bits); | |
755 | prealloc = NULL; | |
756 | BUG_ON(err == -EEXIST); | |
757 | goto out; | |
758 | } | |
759 | ||
760 | state = rb_entry(node, struct extent_state, rb_node); | |
761 | last_start = state->start; | |
762 | last_end = state->end; | |
763 | ||
764 | /* | |
765 | * | ---- desired range ---- | | |
766 | * | state | | |
767 | * | |
768 | * Just lock what we found and keep going | |
769 | */ | |
770 | if (state->start == start && state->end <= end) { | |
771 | set = state->state & bits; | |
772 | if (set && exclusive) { | |
773 | *failed_start = state->start; | |
774 | err = -EEXIST; | |
775 | goto out; | |
776 | } | |
ca664626 | 777 | set_state_bits(tree, state, bits); |
a52d9a80 CM |
778 | start = state->end + 1; |
779 | merge_state(tree, state); | |
780 | goto search_again; | |
781 | } | |
782 | ||
783 | /* | |
784 | * | ---- desired range ---- | | |
785 | * | state | | |
786 | * or | |
787 | * | ------------- state -------------- | | |
788 | * | |
789 | * We need to split the extent we found, and may flip bits on | |
790 | * second half. | |
791 | * | |
792 | * If the extent we found extends past our | |
793 | * range, we just split and search again. It'll get split | |
794 | * again the next time though. | |
795 | * | |
796 | * If the extent we found is inside our range, we set the | |
797 | * desired bit on it. | |
798 | */ | |
799 | if (state->start < start) { | |
800 | set = state->state & bits; | |
801 | if (exclusive && set) { | |
802 | *failed_start = start; | |
803 | err = -EEXIST; | |
804 | goto out; | |
805 | } | |
806 | err = split_state(tree, state, prealloc, start); | |
807 | BUG_ON(err == -EEXIST); | |
808 | prealloc = NULL; | |
809 | if (err) | |
810 | goto out; | |
811 | if (state->end <= end) { | |
ca664626 | 812 | set_state_bits(tree, state, bits); |
a52d9a80 CM |
813 | start = state->end + 1; |
814 | merge_state(tree, state); | |
815 | } else { | |
816 | start = state->start; | |
817 | } | |
818 | goto search_again; | |
819 | } | |
a52d9a80 CM |
820 | /* |
821 | * | ---- desired range ---- | | |
822 | * | state | or | state | | |
823 | * | |
824 | * There's a hole, we need to insert something in it and | |
825 | * ignore the extent we found. | |
826 | */ | |
827 | if (state->start > start) { | |
828 | u64 this_end; | |
829 | if (end < last_start) | |
830 | this_end = end; | |
831 | else | |
832 | this_end = last_start -1; | |
833 | err = insert_state(tree, prealloc, start, this_end, | |
834 | bits); | |
835 | prealloc = NULL; | |
836 | BUG_ON(err == -EEXIST); | |
837 | if (err) | |
838 | goto out; | |
839 | start = this_end + 1; | |
840 | goto search_again; | |
841 | } | |
a8c450b2 CM |
842 | /* |
843 | * | ---- desired range ---- | | |
844 | * | state | | |
845 | * We need to split the extent, and set the bit | |
846 | * on the first half | |
847 | */ | |
848 | if (state->start <= end && state->end > end) { | |
849 | set = state->state & bits; | |
850 | if (exclusive && set) { | |
851 | *failed_start = start; | |
852 | err = -EEXIST; | |
853 | goto out; | |
854 | } | |
855 | err = split_state(tree, state, prealloc, end + 1); | |
856 | BUG_ON(err == -EEXIST); | |
857 | ||
ca664626 | 858 | set_state_bits(tree, prealloc, bits); |
a8c450b2 CM |
859 | merge_state(tree, prealloc); |
860 | prealloc = NULL; | |
861 | goto out; | |
862 | } | |
863 | ||
a52d9a80 CM |
864 | goto search_again; |
865 | ||
866 | out: | |
90f1c19a | 867 | write_unlock_irqrestore(&tree->lock, flags); |
a52d9a80 CM |
868 | if (prealloc) |
869 | free_extent_state(prealloc); | |
870 | ||
871 | return err; | |
872 | ||
873 | search_again: | |
874 | if (start > end) | |
875 | goto out; | |
90f1c19a | 876 | write_unlock_irqrestore(&tree->lock, flags); |
a52d9a80 CM |
877 | if (mask & __GFP_WAIT) |
878 | cond_resched(); | |
879 | goto again; | |
880 | } | |
881 | EXPORT_SYMBOL(set_extent_bit); | |
882 | ||
883 | /* wrappers around set/clear extent bit */ | |
884 | int set_extent_dirty(struct extent_map_tree *tree, u64 start, u64 end, | |
885 | gfp_t mask) | |
886 | { | |
887 | return set_extent_bit(tree, start, end, EXTENT_DIRTY, 0, NULL, | |
888 | mask); | |
889 | } | |
890 | EXPORT_SYMBOL(set_extent_dirty); | |
891 | ||
96b5179d CM |
892 | int set_extent_bits(struct extent_map_tree *tree, u64 start, u64 end, |
893 | int bits, gfp_t mask) | |
894 | { | |
895 | return set_extent_bit(tree, start, end, bits, 0, NULL, | |
896 | mask); | |
897 | } | |
898 | EXPORT_SYMBOL(set_extent_bits); | |
899 | ||
900 | int clear_extent_bits(struct extent_map_tree *tree, u64 start, u64 end, | |
901 | int bits, gfp_t mask) | |
902 | { | |
903 | return clear_extent_bit(tree, start, end, bits, 0, 0, mask); | |
904 | } | |
905 | EXPORT_SYMBOL(clear_extent_bits); | |
906 | ||
b888db2b CM |
907 | int set_extent_delalloc(struct extent_map_tree *tree, u64 start, u64 end, |
908 | gfp_t mask) | |
909 | { | |
910 | return set_extent_bit(tree, start, end, | |
911 | EXTENT_DELALLOC | EXTENT_DIRTY, 0, NULL, | |
912 | mask); | |
913 | } | |
914 | EXPORT_SYMBOL(set_extent_delalloc); | |
915 | ||
a52d9a80 CM |
916 | int clear_extent_dirty(struct extent_map_tree *tree, u64 start, u64 end, |
917 | gfp_t mask) | |
918 | { | |
b888db2b CM |
919 | return clear_extent_bit(tree, start, end, |
920 | EXTENT_DIRTY | EXTENT_DELALLOC, 0, 0, mask); | |
a52d9a80 CM |
921 | } |
922 | EXPORT_SYMBOL(clear_extent_dirty); | |
923 | ||
924 | int set_extent_new(struct extent_map_tree *tree, u64 start, u64 end, | |
925 | gfp_t mask) | |
926 | { | |
927 | return set_extent_bit(tree, start, end, EXTENT_NEW, 0, NULL, | |
928 | mask); | |
929 | } | |
930 | EXPORT_SYMBOL(set_extent_new); | |
931 | ||
932 | int clear_extent_new(struct extent_map_tree *tree, u64 start, u64 end, | |
933 | gfp_t mask) | |
934 | { | |
935 | return clear_extent_bit(tree, start, end, EXTENT_NEW, 0, 0, mask); | |
936 | } | |
937 | EXPORT_SYMBOL(clear_extent_new); | |
938 | ||
939 | int set_extent_uptodate(struct extent_map_tree *tree, u64 start, u64 end, | |
940 | gfp_t mask) | |
941 | { | |
942 | return set_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, NULL, | |
943 | mask); | |
944 | } | |
945 | EXPORT_SYMBOL(set_extent_uptodate); | |
946 | ||
947 | int clear_extent_uptodate(struct extent_map_tree *tree, u64 start, u64 end, | |
948 | gfp_t mask) | |
949 | { | |
950 | return clear_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, 0, mask); | |
951 | } | |
952 | EXPORT_SYMBOL(clear_extent_uptodate); | |
953 | ||
954 | int set_extent_writeback(struct extent_map_tree *tree, u64 start, u64 end, | |
955 | gfp_t mask) | |
956 | { | |
957 | return set_extent_bit(tree, start, end, EXTENT_WRITEBACK, | |
958 | 0, NULL, mask); | |
959 | } | |
960 | EXPORT_SYMBOL(set_extent_writeback); | |
961 | ||
962 | int clear_extent_writeback(struct extent_map_tree *tree, u64 start, u64 end, | |
963 | gfp_t mask) | |
964 | { | |
965 | return clear_extent_bit(tree, start, end, EXTENT_WRITEBACK, 1, 0, mask); | |
966 | } | |
967 | EXPORT_SYMBOL(clear_extent_writeback); | |
968 | ||
969 | int wait_on_extent_writeback(struct extent_map_tree *tree, u64 start, u64 end) | |
970 | { | |
971 | return wait_extent_bit(tree, start, end, EXTENT_WRITEBACK); | |
972 | } | |
973 | EXPORT_SYMBOL(wait_on_extent_writeback); | |
974 | ||
975 | /* | |
976 | * locks a range in ascending order, waiting for any locked regions | |
977 | * it hits on the way. [start,end] are inclusive, and this will sleep. | |
978 | */ | |
979 | int lock_extent(struct extent_map_tree *tree, u64 start, u64 end, gfp_t mask) | |
980 | { | |
981 | int err; | |
982 | u64 failed_start; | |
983 | while (1) { | |
984 | err = set_extent_bit(tree, start, end, EXTENT_LOCKED, 1, | |
985 | &failed_start, mask); | |
986 | if (err == -EEXIST && (mask & __GFP_WAIT)) { | |
987 | wait_extent_bit(tree, failed_start, end, EXTENT_LOCKED); | |
988 | start = failed_start; | |
989 | } else { | |
990 | break; | |
991 | } | |
992 | WARN_ON(start > end); | |
993 | } | |
994 | return err; | |
995 | } | |
996 | EXPORT_SYMBOL(lock_extent); | |
997 | ||
998 | int unlock_extent(struct extent_map_tree *tree, u64 start, u64 end, | |
999 | gfp_t mask) | |
1000 | { | |
1001 | return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, mask); | |
1002 | } | |
1003 | EXPORT_SYMBOL(unlock_extent); | |
1004 | ||
1005 | /* | |
1006 | * helper function to set pages and extents in the tree dirty | |
1007 | */ | |
1008 | int set_range_dirty(struct extent_map_tree *tree, u64 start, u64 end) | |
1009 | { | |
1010 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1011 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
1012 | struct page *page; | |
1013 | ||
1014 | while (index <= end_index) { | |
1015 | page = find_get_page(tree->mapping, index); | |
1016 | BUG_ON(!page); | |
1017 | __set_page_dirty_nobuffers(page); | |
1018 | page_cache_release(page); | |
1019 | index++; | |
1020 | } | |
1021 | set_extent_dirty(tree, start, end, GFP_NOFS); | |
1022 | return 0; | |
1023 | } | |
1024 | EXPORT_SYMBOL(set_range_dirty); | |
1025 | ||
1026 | /* | |
1027 | * helper function to set both pages and extents in the tree writeback | |
1028 | */ | |
1029 | int set_range_writeback(struct extent_map_tree *tree, u64 start, u64 end) | |
1030 | { | |
1031 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1032 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
1033 | struct page *page; | |
1034 | ||
1035 | while (index <= end_index) { | |
1036 | page = find_get_page(tree->mapping, index); | |
1037 | BUG_ON(!page); | |
1038 | set_page_writeback(page); | |
1039 | page_cache_release(page); | |
1040 | index++; | |
1041 | } | |
1042 | set_extent_writeback(tree, start, end, GFP_NOFS); | |
1043 | return 0; | |
1044 | } | |
1045 | EXPORT_SYMBOL(set_range_writeback); | |
1046 | ||
5f39d397 CM |
1047 | int find_first_extent_bit(struct extent_map_tree *tree, u64 start, |
1048 | u64 *start_ret, u64 *end_ret, int bits) | |
1049 | { | |
1050 | struct rb_node *node; | |
1051 | struct extent_state *state; | |
1052 | int ret = 1; | |
1053 | ||
e19caa5f | 1054 | read_lock_irq(&tree->lock); |
5f39d397 CM |
1055 | /* |
1056 | * this search will find all the extents that end after | |
1057 | * our range starts. | |
1058 | */ | |
1059 | node = tree_search(&tree->state, start); | |
1060 | if (!node || IS_ERR(node)) { | |
1061 | goto out; | |
1062 | } | |
1063 | ||
1064 | while(1) { | |
1065 | state = rb_entry(node, struct extent_state, rb_node); | |
e19caa5f | 1066 | if (state->end >= start && (state->state & bits)) { |
5f39d397 CM |
1067 | *start_ret = state->start; |
1068 | *end_ret = state->end; | |
1069 | ret = 0; | |
f510cfec | 1070 | break; |
5f39d397 CM |
1071 | } |
1072 | node = rb_next(node); | |
1073 | if (!node) | |
1074 | break; | |
1075 | } | |
1076 | out: | |
e19caa5f | 1077 | read_unlock_irq(&tree->lock); |
5f39d397 CM |
1078 | return ret; |
1079 | } | |
1080 | EXPORT_SYMBOL(find_first_extent_bit); | |
1081 | ||
b888db2b | 1082 | u64 find_lock_delalloc_range(struct extent_map_tree *tree, |
3e9fd94f | 1083 | u64 *start, u64 *end, u64 max_bytes) |
b888db2b CM |
1084 | { |
1085 | struct rb_node *node; | |
1086 | struct extent_state *state; | |
3e9fd94f | 1087 | u64 cur_start = *start; |
b888db2b CM |
1088 | u64 found = 0; |
1089 | u64 total_bytes = 0; | |
1090 | ||
1091 | write_lock_irq(&tree->lock); | |
1092 | /* | |
1093 | * this search will find all the extents that end after | |
1094 | * our range starts. | |
1095 | */ | |
1096 | search_again: | |
1097 | node = tree_search(&tree->state, cur_start); | |
1098 | if (!node || IS_ERR(node)) { | |
190662b2 | 1099 | *end = (u64)-1; |
b888db2b CM |
1100 | goto out; |
1101 | } | |
1102 | ||
1103 | while(1) { | |
1104 | state = rb_entry(node, struct extent_state, rb_node); | |
3e9fd94f | 1105 | if (found && state->start != cur_start) { |
b888db2b CM |
1106 | goto out; |
1107 | } | |
1108 | if (!(state->state & EXTENT_DELALLOC)) { | |
190662b2 CM |
1109 | if (!found) |
1110 | *end = state->end; | |
b888db2b CM |
1111 | goto out; |
1112 | } | |
3e9fd94f CM |
1113 | if (!found) { |
1114 | struct extent_state *prev_state; | |
1115 | struct rb_node *prev_node = node; | |
1116 | while(1) { | |
1117 | prev_node = rb_prev(prev_node); | |
1118 | if (!prev_node) | |
1119 | break; | |
1120 | prev_state = rb_entry(prev_node, | |
1121 | struct extent_state, | |
1122 | rb_node); | |
1123 | if (!(prev_state->state & EXTENT_DELALLOC)) | |
1124 | break; | |
1125 | state = prev_state; | |
1126 | node = prev_node; | |
b888db2b | 1127 | } |
b888db2b | 1128 | } |
3e9fd94f CM |
1129 | if (state->state & EXTENT_LOCKED) { |
1130 | DEFINE_WAIT(wait); | |
1131 | atomic_inc(&state->refs); | |
1132 | prepare_to_wait(&state->wq, &wait, | |
1133 | TASK_UNINTERRUPTIBLE); | |
1134 | write_unlock_irq(&tree->lock); | |
1135 | schedule(); | |
1136 | write_lock_irq(&tree->lock); | |
1137 | finish_wait(&state->wq, &wait); | |
1138 | free_extent_state(state); | |
1139 | goto search_again; | |
1140 | } | |
1141 | state->state |= EXTENT_LOCKED; | |
1142 | if (!found) | |
1143 | *start = state->start; | |
b888db2b CM |
1144 | found++; |
1145 | *end = state->end; | |
1146 | cur_start = state->end + 1; | |
1147 | node = rb_next(node); | |
1148 | if (!node) | |
1149 | break; | |
944746ec | 1150 | total_bytes += state->end - state->start + 1; |
b888db2b CM |
1151 | if (total_bytes >= max_bytes) |
1152 | break; | |
1153 | } | |
1154 | out: | |
1155 | write_unlock_irq(&tree->lock); | |
1156 | return found; | |
1157 | } | |
1158 | ||
793955bc | 1159 | u64 count_range_bits(struct extent_map_tree *tree, |
1832a6d5 CM |
1160 | u64 *start, u64 search_end, u64 max_bytes, |
1161 | unsigned long bits) | |
793955bc CM |
1162 | { |
1163 | struct rb_node *node; | |
1164 | struct extent_state *state; | |
1165 | u64 cur_start = *start; | |
1166 | u64 total_bytes = 0; | |
1167 | int found = 0; | |
1168 | ||
1832a6d5 CM |
1169 | if (search_end <= cur_start) { |
1170 | printk("search_end %Lu start %Lu\n", search_end, cur_start); | |
1171 | WARN_ON(1); | |
1172 | return 0; | |
1173 | } | |
1174 | ||
793955bc | 1175 | write_lock_irq(&tree->lock); |
1832a6d5 | 1176 | if (cur_start == 0 && bits == EXTENT_DIRTY) { |
ca664626 CM |
1177 | total_bytes = tree->dirty_bytes; |
1178 | goto out; | |
1179 | } | |
793955bc CM |
1180 | /* |
1181 | * this search will find all the extents that end after | |
1182 | * our range starts. | |
1183 | */ | |
1184 | node = tree_search(&tree->state, cur_start); | |
1185 | if (!node || IS_ERR(node)) { | |
1186 | goto out; | |
1187 | } | |
1188 | ||
1189 | while(1) { | |
1190 | state = rb_entry(node, struct extent_state, rb_node); | |
1832a6d5 CM |
1191 | if (state->start > search_end) |
1192 | break; | |
1193 | if (state->end >= cur_start && (state->state & bits)) { | |
1194 | total_bytes += min(search_end, state->end) + 1 - | |
1195 | max(cur_start, state->start); | |
793955bc CM |
1196 | if (total_bytes >= max_bytes) |
1197 | break; | |
1198 | if (!found) { | |
1199 | *start = state->start; | |
1200 | found = 1; | |
1201 | } | |
1202 | } | |
1203 | node = rb_next(node); | |
1204 | if (!node) | |
1205 | break; | |
1206 | } | |
1207 | out: | |
1208 | write_unlock_irq(&tree->lock); | |
1209 | return total_bytes; | |
1210 | } | |
a52d9a80 CM |
1211 | /* |
1212 | * helper function to lock both pages and extents in the tree. | |
1213 | * pages must be locked first. | |
1214 | */ | |
1215 | int lock_range(struct extent_map_tree *tree, u64 start, u64 end) | |
1216 | { | |
1217 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1218 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
1219 | struct page *page; | |
1220 | int err; | |
1221 | ||
1222 | while (index <= end_index) { | |
1223 | page = grab_cache_page(tree->mapping, index); | |
1224 | if (!page) { | |
1225 | err = -ENOMEM; | |
1226 | goto failed; | |
1227 | } | |
1228 | if (IS_ERR(page)) { | |
1229 | err = PTR_ERR(page); | |
1230 | goto failed; | |
1231 | } | |
1232 | index++; | |
1233 | } | |
1234 | lock_extent(tree, start, end, GFP_NOFS); | |
1235 | return 0; | |
1236 | ||
1237 | failed: | |
1238 | /* | |
1239 | * we failed above in getting the page at 'index', so we undo here | |
1240 | * up to but not including the page at 'index' | |
1241 | */ | |
1242 | end_index = index; | |
1243 | index = start >> PAGE_CACHE_SHIFT; | |
1244 | while (index < end_index) { | |
1245 | page = find_get_page(tree->mapping, index); | |
1246 | unlock_page(page); | |
1247 | page_cache_release(page); | |
1248 | index++; | |
1249 | } | |
1250 | return err; | |
1251 | } | |
1252 | EXPORT_SYMBOL(lock_range); | |
1253 | ||
1254 | /* | |
1255 | * helper function to unlock both pages and extents in the tree. | |
1256 | */ | |
1257 | int unlock_range(struct extent_map_tree *tree, u64 start, u64 end) | |
1258 | { | |
1259 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1260 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
1261 | struct page *page; | |
1262 | ||
1263 | while (index <= end_index) { | |
1264 | page = find_get_page(tree->mapping, index); | |
1265 | unlock_page(page); | |
1266 | page_cache_release(page); | |
1267 | index++; | |
1268 | } | |
1269 | unlock_extent(tree, start, end, GFP_NOFS); | |
1270 | return 0; | |
1271 | } | |
1272 | EXPORT_SYMBOL(unlock_range); | |
1273 | ||
07157aac CM |
1274 | int set_state_private(struct extent_map_tree *tree, u64 start, u64 private) |
1275 | { | |
1276 | struct rb_node *node; | |
1277 | struct extent_state *state; | |
1278 | int ret = 0; | |
1279 | ||
1280 | write_lock_irq(&tree->lock); | |
1281 | /* | |
1282 | * this search will find all the extents that end after | |
1283 | * our range starts. | |
1284 | */ | |
1285 | node = tree_search(&tree->state, start); | |
1286 | if (!node || IS_ERR(node)) { | |
1287 | ret = -ENOENT; | |
1288 | goto out; | |
1289 | } | |
1290 | state = rb_entry(node, struct extent_state, rb_node); | |
1291 | if (state->start != start) { | |
1292 | ret = -ENOENT; | |
1293 | goto out; | |
1294 | } | |
1295 | state->private = private; | |
1296 | out: | |
1297 | write_unlock_irq(&tree->lock); | |
1298 | return ret; | |
07157aac CM |
1299 | } |
1300 | ||
1301 | int get_state_private(struct extent_map_tree *tree, u64 start, u64 *private) | |
1302 | { | |
1303 | struct rb_node *node; | |
1304 | struct extent_state *state; | |
1305 | int ret = 0; | |
1306 | ||
1307 | read_lock_irq(&tree->lock); | |
1308 | /* | |
1309 | * this search will find all the extents that end after | |
1310 | * our range starts. | |
1311 | */ | |
1312 | node = tree_search(&tree->state, start); | |
1313 | if (!node || IS_ERR(node)) { | |
1314 | ret = -ENOENT; | |
1315 | goto out; | |
1316 | } | |
1317 | state = rb_entry(node, struct extent_state, rb_node); | |
1318 | if (state->start != start) { | |
1319 | ret = -ENOENT; | |
1320 | goto out; | |
1321 | } | |
1322 | *private = state->private; | |
1323 | out: | |
1324 | read_unlock_irq(&tree->lock); | |
1325 | return ret; | |
1326 | } | |
1327 | ||
a52d9a80 CM |
1328 | /* |
1329 | * searches a range in the state tree for a given mask. | |
1330 | * If 'filled' == 1, this returns 1 only if ever extent in the tree | |
1331 | * has the bits set. Otherwise, 1 is returned if any bit in the | |
1332 | * range is found set. | |
1333 | */ | |
1a5bc167 CM |
1334 | int test_range_bit(struct extent_map_tree *tree, u64 start, u64 end, |
1335 | int bits, int filled) | |
a52d9a80 CM |
1336 | { |
1337 | struct extent_state *state = NULL; | |
1338 | struct rb_node *node; | |
1339 | int bitset = 0; | |
1340 | ||
1341 | read_lock_irq(&tree->lock); | |
1342 | node = tree_search(&tree->state, start); | |
1343 | while (node && start <= end) { | |
1344 | state = rb_entry(node, struct extent_state, rb_node); | |
a52d9a80 CM |
1345 | |
1346 | if (filled && state->start > start) { | |
1347 | bitset = 0; | |
1348 | break; | |
1349 | } | |
0591fb56 CM |
1350 | |
1351 | if (state->start > end) | |
1352 | break; | |
1353 | ||
a52d9a80 CM |
1354 | if (state->state & bits) { |
1355 | bitset = 1; | |
1356 | if (!filled) | |
1357 | break; | |
1358 | } else if (filled) { | |
1359 | bitset = 0; | |
1360 | break; | |
1361 | } | |
1362 | start = state->end + 1; | |
1363 | if (start > end) | |
1364 | break; | |
1365 | node = rb_next(node); | |
f0c5da14 Y |
1366 | if (!node) { |
1367 | if (filled) | |
1368 | bitset = 0; | |
1369 | break; | |
1370 | } | |
a52d9a80 CM |
1371 | } |
1372 | read_unlock_irq(&tree->lock); | |
1373 | return bitset; | |
1374 | } | |
1a5bc167 | 1375 | EXPORT_SYMBOL(test_range_bit); |
a52d9a80 CM |
1376 | |
1377 | /* | |
1378 | * helper function to set a given page up to date if all the | |
1379 | * extents in the tree for that page are up to date | |
1380 | */ | |
1381 | static int check_page_uptodate(struct extent_map_tree *tree, | |
1382 | struct page *page) | |
1383 | { | |
35ebb934 | 1384 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; |
a52d9a80 CM |
1385 | u64 end = start + PAGE_CACHE_SIZE - 1; |
1386 | if (test_range_bit(tree, start, end, EXTENT_UPTODATE, 1)) | |
1387 | SetPageUptodate(page); | |
1388 | return 0; | |
1389 | } | |
1390 | ||
1391 | /* | |
1392 | * helper function to unlock a page if all the extents in the tree | |
1393 | * for that page are unlocked | |
1394 | */ | |
1395 | static int check_page_locked(struct extent_map_tree *tree, | |
1396 | struct page *page) | |
1397 | { | |
35ebb934 | 1398 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; |
a52d9a80 CM |
1399 | u64 end = start + PAGE_CACHE_SIZE - 1; |
1400 | if (!test_range_bit(tree, start, end, EXTENT_LOCKED, 0)) | |
1401 | unlock_page(page); | |
1402 | return 0; | |
1403 | } | |
1404 | ||
1405 | /* | |
1406 | * helper function to end page writeback if all the extents | |
1407 | * in the tree for that page are done with writeback | |
1408 | */ | |
1409 | static int check_page_writeback(struct extent_map_tree *tree, | |
1410 | struct page *page) | |
1411 | { | |
35ebb934 | 1412 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; |
a52d9a80 CM |
1413 | u64 end = start + PAGE_CACHE_SIZE - 1; |
1414 | if (!test_range_bit(tree, start, end, EXTENT_WRITEBACK, 0)) | |
1415 | end_page_writeback(page); | |
1416 | return 0; | |
1417 | } | |
1418 | ||
1419 | /* lots and lots of room for performance fixes in the end_bio funcs */ | |
1420 | ||
1421 | /* | |
1422 | * after a writepage IO is done, we need to: | |
1423 | * clear the uptodate bits on error | |
1424 | * clear the writeback bits in the extent tree for this IO | |
1425 | * end_page_writeback if the page has no more pending IO | |
1426 | * | |
1427 | * Scheduling is not allowed, so the extent state tree is expected | |
1428 | * to have one and only one object corresponding to this IO. | |
1429 | */ | |
0a2118df JA |
1430 | #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23) |
1431 | static void end_bio_extent_writepage(struct bio *bio, int err) | |
1432 | #else | |
a52d9a80 CM |
1433 | static int end_bio_extent_writepage(struct bio *bio, |
1434 | unsigned int bytes_done, int err) | |
0a2118df | 1435 | #endif |
a52d9a80 CM |
1436 | { |
1437 | const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); | |
1438 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; | |
1439 | struct extent_map_tree *tree = bio->bi_private; | |
1440 | u64 start; | |
1441 | u64 end; | |
1442 | int whole_page; | |
1443 | ||
0a2118df | 1444 | #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23) |
a52d9a80 CM |
1445 | if (bio->bi_size) |
1446 | return 1; | |
0a2118df | 1447 | #endif |
a52d9a80 CM |
1448 | |
1449 | do { | |
1450 | struct page *page = bvec->bv_page; | |
35ebb934 CM |
1451 | start = ((u64)page->index << PAGE_CACHE_SHIFT) + |
1452 | bvec->bv_offset; | |
a52d9a80 CM |
1453 | end = start + bvec->bv_len - 1; |
1454 | ||
1455 | if (bvec->bv_offset == 0 && bvec->bv_len == PAGE_CACHE_SIZE) | |
1456 | whole_page = 1; | |
1457 | else | |
1458 | whole_page = 0; | |
1459 | ||
1460 | if (--bvec >= bio->bi_io_vec) | |
1461 | prefetchw(&bvec->bv_page->flags); | |
1462 | ||
1463 | if (!uptodate) { | |
1464 | clear_extent_uptodate(tree, start, end, GFP_ATOMIC); | |
1465 | ClearPageUptodate(page); | |
1466 | SetPageError(page); | |
1467 | } | |
1468 | clear_extent_writeback(tree, start, end, GFP_ATOMIC); | |
1469 | ||
1470 | if (whole_page) | |
1471 | end_page_writeback(page); | |
1472 | else | |
1473 | check_page_writeback(tree, page); | |
0e2752a7 CH |
1474 | if (tree->ops && tree->ops->writepage_end_io_hook) |
1475 | tree->ops->writepage_end_io_hook(page, start, end); | |
a52d9a80 CM |
1476 | } while (bvec >= bio->bi_io_vec); |
1477 | ||
1478 | bio_put(bio); | |
0a2118df | 1479 | #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23) |
a52d9a80 | 1480 | return 0; |
0a2118df | 1481 | #endif |
a52d9a80 CM |
1482 | } |
1483 | ||
1484 | /* | |
1485 | * after a readpage IO is done, we need to: | |
1486 | * clear the uptodate bits on error | |
1487 | * set the uptodate bits if things worked | |
1488 | * set the page up to date if all extents in the tree are uptodate | |
1489 | * clear the lock bit in the extent tree | |
1490 | * unlock the page if there are no other extents locked for it | |
1491 | * | |
1492 | * Scheduling is not allowed, so the extent state tree is expected | |
1493 | * to have one and only one object corresponding to this IO. | |
1494 | */ | |
0a2118df JA |
1495 | #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23) |
1496 | static void end_bio_extent_readpage(struct bio *bio, int err) | |
1497 | #else | |
a52d9a80 CM |
1498 | static int end_bio_extent_readpage(struct bio *bio, |
1499 | unsigned int bytes_done, int err) | |
0a2118df | 1500 | #endif |
a52d9a80 | 1501 | { |
07157aac | 1502 | int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); |
a52d9a80 CM |
1503 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; |
1504 | struct extent_map_tree *tree = bio->bi_private; | |
1505 | u64 start; | |
1506 | u64 end; | |
1507 | int whole_page; | |
07157aac | 1508 | int ret; |
a52d9a80 | 1509 | |
0a2118df | 1510 | #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23) |
a52d9a80 CM |
1511 | if (bio->bi_size) |
1512 | return 1; | |
0a2118df | 1513 | #endif |
a52d9a80 CM |
1514 | |
1515 | do { | |
1516 | struct page *page = bvec->bv_page; | |
35ebb934 CM |
1517 | start = ((u64)page->index << PAGE_CACHE_SHIFT) + |
1518 | bvec->bv_offset; | |
a52d9a80 CM |
1519 | end = start + bvec->bv_len - 1; |
1520 | ||
1521 | if (bvec->bv_offset == 0 && bvec->bv_len == PAGE_CACHE_SIZE) | |
1522 | whole_page = 1; | |
1523 | else | |
1524 | whole_page = 0; | |
1525 | ||
1526 | if (--bvec >= bio->bi_io_vec) | |
1527 | prefetchw(&bvec->bv_page->flags); | |
1528 | ||
07157aac CM |
1529 | if (uptodate && tree->ops && tree->ops->readpage_end_io_hook) { |
1530 | ret = tree->ops->readpage_end_io_hook(page, start, end); | |
1531 | if (ret) | |
1532 | uptodate = 0; | |
1533 | } | |
a52d9a80 CM |
1534 | if (uptodate) { |
1535 | set_extent_uptodate(tree, start, end, GFP_ATOMIC); | |
1536 | if (whole_page) | |
1537 | SetPageUptodate(page); | |
1538 | else | |
1539 | check_page_uptodate(tree, page); | |
1540 | } else { | |
1541 | ClearPageUptodate(page); | |
1542 | SetPageError(page); | |
1543 | } | |
1544 | ||
1545 | unlock_extent(tree, start, end, GFP_ATOMIC); | |
1546 | ||
1547 | if (whole_page) | |
1548 | unlock_page(page); | |
1549 | else | |
1550 | check_page_locked(tree, page); | |
1551 | } while (bvec >= bio->bi_io_vec); | |
1552 | ||
1553 | bio_put(bio); | |
0a2118df | 1554 | #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23) |
a52d9a80 | 1555 | return 0; |
0a2118df | 1556 | #endif |
a52d9a80 CM |
1557 | } |
1558 | ||
1559 | /* | |
1560 | * IO done from prepare_write is pretty simple, we just unlock | |
1561 | * the structs in the extent tree when done, and set the uptodate bits | |
1562 | * as appropriate. | |
1563 | */ | |
0a2118df JA |
1564 | #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23) |
1565 | static void end_bio_extent_preparewrite(struct bio *bio, int err) | |
1566 | #else | |
a52d9a80 CM |
1567 | static int end_bio_extent_preparewrite(struct bio *bio, |
1568 | unsigned int bytes_done, int err) | |
0a2118df | 1569 | #endif |
a52d9a80 CM |
1570 | { |
1571 | const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); | |
1572 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; | |
1573 | struct extent_map_tree *tree = bio->bi_private; | |
1574 | u64 start; | |
1575 | u64 end; | |
1576 | ||
0a2118df | 1577 | #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23) |
a52d9a80 CM |
1578 | if (bio->bi_size) |
1579 | return 1; | |
0a2118df | 1580 | #endif |
a52d9a80 CM |
1581 | |
1582 | do { | |
1583 | struct page *page = bvec->bv_page; | |
35ebb934 CM |
1584 | start = ((u64)page->index << PAGE_CACHE_SHIFT) + |
1585 | bvec->bv_offset; | |
a52d9a80 CM |
1586 | end = start + bvec->bv_len - 1; |
1587 | ||
1588 | if (--bvec >= bio->bi_io_vec) | |
1589 | prefetchw(&bvec->bv_page->flags); | |
1590 | ||
1591 | if (uptodate) { | |
1592 | set_extent_uptodate(tree, start, end, GFP_ATOMIC); | |
1593 | } else { | |
1594 | ClearPageUptodate(page); | |
1595 | SetPageError(page); | |
1596 | } | |
1597 | ||
1598 | unlock_extent(tree, start, end, GFP_ATOMIC); | |
1599 | ||
1600 | } while (bvec >= bio->bi_io_vec); | |
1601 | ||
1602 | bio_put(bio); | |
0a2118df | 1603 | #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23) |
a52d9a80 | 1604 | return 0; |
0a2118df | 1605 | #endif |
a52d9a80 CM |
1606 | } |
1607 | ||
b293f02e CM |
1608 | static struct bio * |
1609 | extent_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs, | |
1610 | gfp_t gfp_flags) | |
a52d9a80 CM |
1611 | { |
1612 | struct bio *bio; | |
a52d9a80 | 1613 | |
b293f02e | 1614 | bio = bio_alloc(gfp_flags, nr_vecs); |
a52d9a80 | 1615 | |
b293f02e CM |
1616 | if (bio == NULL && (current->flags & PF_MEMALLOC)) { |
1617 | while (!bio && (nr_vecs /= 2)) | |
1618 | bio = bio_alloc(gfp_flags, nr_vecs); | |
1619 | } | |
a52d9a80 | 1620 | |
b293f02e CM |
1621 | if (bio) { |
1622 | bio->bi_bdev = bdev; | |
1623 | bio->bi_sector = first_sector; | |
1624 | } | |
1625 | return bio; | |
1626 | } | |
a52d9a80 | 1627 | |
b293f02e CM |
1628 | static int submit_one_bio(int rw, struct bio *bio) |
1629 | { | |
6da6abae | 1630 | u64 maxsector; |
b293f02e | 1631 | int ret = 0; |
6da6abae | 1632 | |
a52d9a80 | 1633 | bio_get(bio); |
6da6abae CM |
1634 | |
1635 | maxsector = bio->bi_bdev->bd_inode->i_size >> 9; | |
1636 | if (maxsector < bio->bi_sector) { | |
1637 | printk("sector too large max %Lu got %llu\n", maxsector, | |
1638 | (unsigned long long)bio->bi_sector); | |
1639 | WARN_ON(1); | |
1640 | } | |
1641 | ||
a52d9a80 | 1642 | submit_bio(rw, bio); |
a52d9a80 CM |
1643 | if (bio_flagged(bio, BIO_EOPNOTSUPP)) |
1644 | ret = -EOPNOTSUPP; | |
a52d9a80 CM |
1645 | bio_put(bio); |
1646 | return ret; | |
1647 | } | |
1648 | ||
b293f02e CM |
1649 | static int submit_extent_page(int rw, struct extent_map_tree *tree, |
1650 | struct page *page, sector_t sector, | |
1651 | size_t size, unsigned long offset, | |
1652 | struct block_device *bdev, | |
1653 | struct bio **bio_ret, | |
3ab2fb5a | 1654 | unsigned long max_pages, |
b293f02e CM |
1655 | bio_end_io_t end_io_func) |
1656 | { | |
1657 | int ret = 0; | |
1658 | struct bio *bio; | |
1659 | int nr; | |
1660 | ||
1661 | if (bio_ret && *bio_ret) { | |
1662 | bio = *bio_ret; | |
1663 | if (bio->bi_sector + (bio->bi_size >> 9) != sector || | |
1664 | bio_add_page(bio, page, size, offset) < size) { | |
1665 | ret = submit_one_bio(rw, bio); | |
1666 | bio = NULL; | |
1667 | } else { | |
1668 | return 0; | |
1669 | } | |
1670 | } | |
3ab2fb5a | 1671 | nr = min_t(int, max_pages, bio_get_nr_vecs(bdev)); |
b293f02e CM |
1672 | bio = extent_bio_alloc(bdev, sector, nr, GFP_NOFS | __GFP_HIGH); |
1673 | if (!bio) { | |
1674 | printk("failed to allocate bio nr %d\n", nr); | |
1675 | } | |
1676 | bio_add_page(bio, page, size, offset); | |
1677 | bio->bi_end_io = end_io_func; | |
1678 | bio->bi_private = tree; | |
1679 | if (bio_ret) { | |
1680 | *bio_ret = bio; | |
1681 | } else { | |
1682 | ret = submit_one_bio(rw, bio); | |
1683 | } | |
1684 | ||
1685 | return ret; | |
1686 | } | |
1687 | ||
b3cfa35a CH |
1688 | void set_page_extent_mapped(struct page *page) |
1689 | { | |
1690 | if (!PagePrivate(page)) { | |
1691 | SetPagePrivate(page); | |
1692 | WARN_ON(!page->mapping->a_ops->invalidatepage); | |
19c00ddc | 1693 | set_page_private(page, EXTENT_PAGE_PRIVATE); |
b3cfa35a CH |
1694 | page_cache_get(page); |
1695 | } | |
1696 | } | |
1697 | ||
55c69072 CM |
1698 | void set_page_extent_head(struct page *page, unsigned long len) |
1699 | { | |
55c69072 CM |
1700 | set_page_private(page, EXTENT_PAGE_PRIVATE_FIRST_PAGE | len << 2); |
1701 | } | |
1702 | ||
a52d9a80 CM |
1703 | /* |
1704 | * basic readpage implementation. Locked extent state structs are inserted | |
1705 | * into the tree that are removed when the IO is done (by the end_io | |
1706 | * handlers) | |
1707 | */ | |
3ab2fb5a CM |
1708 | static int __extent_read_full_page(struct extent_map_tree *tree, |
1709 | struct page *page, | |
1710 | get_extent_t *get_extent, | |
1711 | struct bio **bio) | |
a52d9a80 CM |
1712 | { |
1713 | struct inode *inode = page->mapping->host; | |
35ebb934 | 1714 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; |
a52d9a80 CM |
1715 | u64 page_end = start + PAGE_CACHE_SIZE - 1; |
1716 | u64 end; | |
1717 | u64 cur = start; | |
1718 | u64 extent_offset; | |
1719 | u64 last_byte = i_size_read(inode); | |
1720 | u64 block_start; | |
1721 | u64 cur_end; | |
1722 | sector_t sector; | |
1723 | struct extent_map *em; | |
1724 | struct block_device *bdev; | |
1725 | int ret; | |
1726 | int nr = 0; | |
1727 | size_t page_offset = 0; | |
1728 | size_t iosize; | |
1729 | size_t blocksize = inode->i_sb->s_blocksize; | |
1730 | ||
b3cfa35a | 1731 | set_page_extent_mapped(page); |
a52d9a80 CM |
1732 | |
1733 | end = page_end; | |
1734 | lock_extent(tree, start, end, GFP_NOFS); | |
1735 | ||
1736 | while (cur <= end) { | |
1737 | if (cur >= last_byte) { | |
6da6abae | 1738 | char *userpage; |
a52d9a80 | 1739 | iosize = PAGE_CACHE_SIZE - page_offset; |
6da6abae CM |
1740 | userpage = kmap_atomic(page, KM_USER0); |
1741 | memset(userpage + page_offset, 0, iosize); | |
1742 | flush_dcache_page(page); | |
1743 | kunmap_atomic(userpage, KM_USER0); | |
a52d9a80 CM |
1744 | set_extent_uptodate(tree, cur, cur + iosize - 1, |
1745 | GFP_NOFS); | |
1746 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); | |
1747 | break; | |
1748 | } | |
1749 | em = get_extent(inode, page, page_offset, cur, end, 0); | |
1750 | if (IS_ERR(em) || !em) { | |
1751 | SetPageError(page); | |
1752 | unlock_extent(tree, cur, end, GFP_NOFS); | |
1753 | break; | |
1754 | } | |
1755 | ||
1756 | extent_offset = cur - em->start; | |
1757 | BUG_ON(em->end < cur); | |
1758 | BUG_ON(end < cur); | |
1759 | ||
1760 | iosize = min(em->end - cur, end - cur) + 1; | |
1761 | cur_end = min(em->end, end); | |
1762 | iosize = (iosize + blocksize - 1) & ~((u64)blocksize - 1); | |
1763 | sector = (em->block_start + extent_offset) >> 9; | |
1764 | bdev = em->bdev; | |
1765 | block_start = em->block_start; | |
1766 | free_extent_map(em); | |
1767 | em = NULL; | |
1768 | ||
1769 | /* we've found a hole, just zero and go on */ | |
5f39d397 | 1770 | if (block_start == EXTENT_MAP_HOLE) { |
6da6abae CM |
1771 | char *userpage; |
1772 | userpage = kmap_atomic(page, KM_USER0); | |
1773 | memset(userpage + page_offset, 0, iosize); | |
1774 | flush_dcache_page(page); | |
1775 | kunmap_atomic(userpage, KM_USER0); | |
1776 | ||
a52d9a80 CM |
1777 | set_extent_uptodate(tree, cur, cur + iosize - 1, |
1778 | GFP_NOFS); | |
1779 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); | |
1780 | cur = cur + iosize; | |
1781 | page_offset += iosize; | |
1782 | continue; | |
1783 | } | |
1784 | /* the get_extent function already copied into the page */ | |
1785 | if (test_range_bit(tree, cur, cur_end, EXTENT_UPTODATE, 1)) { | |
1786 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); | |
1787 | cur = cur + iosize; | |
1788 | page_offset += iosize; | |
1789 | continue; | |
1790 | } | |
1791 | ||
07157aac CM |
1792 | ret = 0; |
1793 | if (tree->ops && tree->ops->readpage_io_hook) { | |
1794 | ret = tree->ops->readpage_io_hook(page, cur, | |
1795 | cur + iosize - 1); | |
1796 | } | |
1797 | if (!ret) { | |
3ab2fb5a CM |
1798 | unsigned long nr = (last_byte >> PAGE_CACHE_SHIFT) + 1; |
1799 | nr -= page->index; | |
07157aac | 1800 | ret = submit_extent_page(READ, tree, page, |
3ab2fb5a CM |
1801 | sector, iosize, page_offset, |
1802 | bdev, bio, nr, | |
1803 | end_bio_extent_readpage); | |
07157aac | 1804 | } |
a52d9a80 CM |
1805 | if (ret) |
1806 | SetPageError(page); | |
1807 | cur = cur + iosize; | |
1808 | page_offset += iosize; | |
1809 | nr++; | |
1810 | } | |
1811 | if (!nr) { | |
1812 | if (!PageError(page)) | |
1813 | SetPageUptodate(page); | |
1814 | unlock_page(page); | |
1815 | } | |
1816 | return 0; | |
1817 | } | |
3ab2fb5a CM |
1818 | |
1819 | int extent_read_full_page(struct extent_map_tree *tree, struct page *page, | |
1820 | get_extent_t *get_extent) | |
1821 | { | |
1822 | struct bio *bio = NULL; | |
1823 | int ret; | |
1824 | ||
1825 | ret = __extent_read_full_page(tree, page, get_extent, &bio); | |
1826 | if (bio) | |
1827 | submit_one_bio(READ, bio); | |
1828 | return ret; | |
1829 | } | |
a52d9a80 CM |
1830 | EXPORT_SYMBOL(extent_read_full_page); |
1831 | ||
1832 | /* | |
1833 | * the writepage semantics are similar to regular writepage. extent | |
1834 | * records are inserted to lock ranges in the tree, and as dirty areas | |
1835 | * are found, they are marked writeback. Then the lock bits are removed | |
1836 | * and the end_io handler clears the writeback ranges | |
1837 | */ | |
b293f02e CM |
1838 | static int __extent_writepage(struct page *page, struct writeback_control *wbc, |
1839 | void *data) | |
a52d9a80 CM |
1840 | { |
1841 | struct inode *inode = page->mapping->host; | |
b293f02e CM |
1842 | struct extent_page_data *epd = data; |
1843 | struct extent_map_tree *tree = epd->tree; | |
35ebb934 | 1844 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; |
3e9fd94f | 1845 | u64 delalloc_start; |
a52d9a80 CM |
1846 | u64 page_end = start + PAGE_CACHE_SIZE - 1; |
1847 | u64 end; | |
1848 | u64 cur = start; | |
1849 | u64 extent_offset; | |
1850 | u64 last_byte = i_size_read(inode); | |
1851 | u64 block_start; | |
179e29e4 | 1852 | u64 iosize; |
a52d9a80 CM |
1853 | sector_t sector; |
1854 | struct extent_map *em; | |
1855 | struct block_device *bdev; | |
1856 | int ret; | |
1857 | int nr = 0; | |
1858 | size_t page_offset = 0; | |
a52d9a80 CM |
1859 | size_t blocksize; |
1860 | loff_t i_size = i_size_read(inode); | |
1861 | unsigned long end_index = i_size >> PAGE_CACHE_SHIFT; | |
b888db2b CM |
1862 | u64 nr_delalloc; |
1863 | u64 delalloc_end; | |
a52d9a80 | 1864 | |
b888db2b | 1865 | WARN_ON(!PageLocked(page)); |
a52d9a80 CM |
1866 | if (page->index > end_index) { |
1867 | clear_extent_dirty(tree, start, page_end, GFP_NOFS); | |
1868 | unlock_page(page); | |
1869 | return 0; | |
1870 | } | |
1871 | ||
1872 | if (page->index == end_index) { | |
6da6abae CM |
1873 | char *userpage; |
1874 | ||
a52d9a80 | 1875 | size_t offset = i_size & (PAGE_CACHE_SIZE - 1); |
6da6abae CM |
1876 | |
1877 | userpage = kmap_atomic(page, KM_USER0); | |
1878 | memset(userpage + offset, 0, PAGE_CACHE_SIZE - offset); | |
1879 | flush_dcache_page(page); | |
1880 | kunmap_atomic(userpage, KM_USER0); | |
a52d9a80 CM |
1881 | } |
1882 | ||
b3cfa35a | 1883 | set_page_extent_mapped(page); |
a52d9a80 | 1884 | |
3e9fd94f CM |
1885 | delalloc_start = start; |
1886 | delalloc_end = 0; | |
1887 | while(delalloc_end < page_end) { | |
1888 | nr_delalloc = find_lock_delalloc_range(tree, &delalloc_start, | |
1889 | &delalloc_end, | |
1890 | 128 * 1024 * 1024); | |
190662b2 CM |
1891 | if (nr_delalloc == 0) { |
1892 | delalloc_start = delalloc_end + 1; | |
1893 | continue; | |
1894 | } | |
3e9fd94f CM |
1895 | tree->ops->fill_delalloc(inode, delalloc_start, |
1896 | delalloc_end); | |
1897 | clear_extent_bit(tree, delalloc_start, | |
1898 | delalloc_end, | |
1899 | EXTENT_LOCKED | EXTENT_DELALLOC, | |
1900 | 1, 0, GFP_NOFS); | |
1901 | delalloc_start = delalloc_end + 1; | |
b888db2b | 1902 | } |
3e9fd94f | 1903 | lock_extent(tree, start, page_end, GFP_NOFS); |
b888db2b CM |
1904 | |
1905 | end = page_end; | |
1906 | if (test_range_bit(tree, start, page_end, EXTENT_DELALLOC, 0)) { | |
1907 | printk("found delalloc bits after lock_extent\n"); | |
1908 | } | |
a52d9a80 CM |
1909 | |
1910 | if (last_byte <= start) { | |
1911 | clear_extent_dirty(tree, start, page_end, GFP_NOFS); | |
1912 | goto done; | |
1913 | } | |
1914 | ||
1915 | set_extent_uptodate(tree, start, page_end, GFP_NOFS); | |
1916 | blocksize = inode->i_sb->s_blocksize; | |
1917 | ||
1918 | while (cur <= end) { | |
1919 | if (cur >= last_byte) { | |
1920 | clear_extent_dirty(tree, cur, page_end, GFP_NOFS); | |
1921 | break; | |
1922 | } | |
b293f02e | 1923 | em = epd->get_extent(inode, page, page_offset, cur, end, 1); |
a52d9a80 CM |
1924 | if (IS_ERR(em) || !em) { |
1925 | SetPageError(page); | |
1926 | break; | |
1927 | } | |
1928 | ||
1929 | extent_offset = cur - em->start; | |
1930 | BUG_ON(em->end < cur); | |
1931 | BUG_ON(end < cur); | |
1932 | iosize = min(em->end - cur, end - cur) + 1; | |
1933 | iosize = (iosize + blocksize - 1) & ~((u64)blocksize - 1); | |
1934 | sector = (em->block_start + extent_offset) >> 9; | |
1935 | bdev = em->bdev; | |
1936 | block_start = em->block_start; | |
1937 | free_extent_map(em); | |
1938 | em = NULL; | |
1939 | ||
5f39d397 CM |
1940 | if (block_start == EXTENT_MAP_HOLE || |
1941 | block_start == EXTENT_MAP_INLINE) { | |
a52d9a80 CM |
1942 | clear_extent_dirty(tree, cur, |
1943 | cur + iosize - 1, GFP_NOFS); | |
1944 | cur = cur + iosize; | |
1945 | page_offset += iosize; | |
1946 | continue; | |
1947 | } | |
1948 | ||
1949 | /* leave this out until we have a page_mkwrite call */ | |
1950 | if (0 && !test_range_bit(tree, cur, cur + iosize - 1, | |
1951 | EXTENT_DIRTY, 0)) { | |
1952 | cur = cur + iosize; | |
1953 | page_offset += iosize; | |
1954 | continue; | |
1955 | } | |
1956 | clear_extent_dirty(tree, cur, cur + iosize - 1, GFP_NOFS); | |
b06355f0 CH |
1957 | if (tree->ops && tree->ops->writepage_io_hook) { |
1958 | ret = tree->ops->writepage_io_hook(page, cur, | |
1959 | cur + iosize - 1); | |
1960 | } else { | |
1961 | ret = 0; | |
1962 | } | |
a52d9a80 CM |
1963 | if (ret) |
1964 | SetPageError(page); | |
07157aac | 1965 | else { |
7073c8e8 | 1966 | unsigned long max_nr = end_index + 1; |
07157aac | 1967 | set_range_writeback(tree, cur, cur + iosize - 1); |
7073c8e8 CM |
1968 | if (!PageWriteback(page)) { |
1969 | printk("warning page %lu not writeback, " | |
1970 | "cur %llu end %llu\n", page->index, | |
1971 | (unsigned long long)cur, | |
1972 | (unsigned long long)end); | |
1973 | } | |
b293f02e | 1974 | |
07157aac CM |
1975 | ret = submit_extent_page(WRITE, tree, page, sector, |
1976 | iosize, page_offset, bdev, | |
7073c8e8 | 1977 | &epd->bio, max_nr, |
07157aac CM |
1978 | end_bio_extent_writepage); |
1979 | if (ret) | |
1980 | SetPageError(page); | |
1981 | } | |
a52d9a80 CM |
1982 | cur = cur + iosize; |
1983 | page_offset += iosize; | |
1984 | nr++; | |
1985 | } | |
1986 | done: | |
7073c8e8 CM |
1987 | if (nr == 0) { |
1988 | /* make sure the mapping tag for page dirty gets cleared */ | |
1989 | set_page_writeback(page); | |
1990 | end_page_writeback(page); | |
1991 | } | |
a52d9a80 CM |
1992 | unlock_extent(tree, start, page_end, GFP_NOFS); |
1993 | unlock_page(page); | |
1994 | return 0; | |
1995 | } | |
b293f02e | 1996 | |
6da6abae CM |
1997 | #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18) |
1998 | ||
1999 | /* Taken directly from 2.6.23 for 2.6.18 back port */ | |
2000 | typedef int (*writepage_t)(struct page *page, struct writeback_control *wbc, | |
2001 | void *data); | |
2002 | ||
2003 | /** | |
2004 | * write_cache_pages - walk the list of dirty pages of the given address space | |
2005 | * and write all of them. | |
2006 | * @mapping: address space structure to write | |
2007 | * @wbc: subtract the number of written pages from *@wbc->nr_to_write | |
2008 | * @writepage: function called for each page | |
2009 | * @data: data passed to writepage function | |
2010 | * | |
2011 | * If a page is already under I/O, write_cache_pages() skips it, even | |
2012 | * if it's dirty. This is desirable behaviour for memory-cleaning writeback, | |
2013 | * but it is INCORRECT for data-integrity system calls such as fsync(). fsync() | |
2014 | * and msync() need to guarantee that all the data which was dirty at the time | |
2015 | * the call was made get new I/O started against them. If wbc->sync_mode is | |
2016 | * WB_SYNC_ALL then we were called for data integrity and we must wait for | |
2017 | * existing IO to complete. | |
2018 | */ | |
2019 | static int write_cache_pages(struct address_space *mapping, | |
2020 | struct writeback_control *wbc, writepage_t writepage, | |
2021 | void *data) | |
2022 | { | |
2023 | struct backing_dev_info *bdi = mapping->backing_dev_info; | |
2024 | int ret = 0; | |
2025 | int done = 0; | |
2026 | struct pagevec pvec; | |
2027 | int nr_pages; | |
2028 | pgoff_t index; | |
2029 | pgoff_t end; /* Inclusive */ | |
2030 | int scanned = 0; | |
2031 | int range_whole = 0; | |
2032 | ||
2033 | if (wbc->nonblocking && bdi_write_congested(bdi)) { | |
2034 | wbc->encountered_congestion = 1; | |
2035 | return 0; | |
2036 | } | |
2037 | ||
2038 | pagevec_init(&pvec, 0); | |
2039 | if (wbc->range_cyclic) { | |
2040 | index = mapping->writeback_index; /* Start from prev offset */ | |
2041 | end = -1; | |
2042 | } else { | |
2043 | index = wbc->range_start >> PAGE_CACHE_SHIFT; | |
2044 | end = wbc->range_end >> PAGE_CACHE_SHIFT; | |
2045 | if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) | |
2046 | range_whole = 1; | |
2047 | scanned = 1; | |
2048 | } | |
2049 | retry: | |
2050 | while (!done && (index <= end) && | |
2051 | (nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, | |
2052 | PAGECACHE_TAG_DIRTY, | |
2053 | min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1))) { | |
2054 | unsigned i; | |
2055 | ||
2056 | scanned = 1; | |
2057 | for (i = 0; i < nr_pages; i++) { | |
2058 | struct page *page = pvec.pages[i]; | |
2059 | ||
2060 | /* | |
2061 | * At this point we hold neither mapping->tree_lock nor | |
2062 | * lock on the page itself: the page may be truncated or | |
2063 | * invalidated (changing page->mapping to NULL), or even | |
2064 | * swizzled back from swapper_space to tmpfs file | |
2065 | * mapping | |
2066 | */ | |
2067 | lock_page(page); | |
2068 | ||
2069 | if (unlikely(page->mapping != mapping)) { | |
2070 | unlock_page(page); | |
2071 | continue; | |
2072 | } | |
2073 | ||
2074 | if (!wbc->range_cyclic && page->index > end) { | |
2075 | done = 1; | |
2076 | unlock_page(page); | |
2077 | continue; | |
2078 | } | |
2079 | ||
2080 | if (wbc->sync_mode != WB_SYNC_NONE) | |
2081 | wait_on_page_writeback(page); | |
2082 | ||
2083 | if (PageWriteback(page) || | |
2084 | !clear_page_dirty_for_io(page)) { | |
2085 | unlock_page(page); | |
2086 | continue; | |
2087 | } | |
2088 | ||
2089 | ret = (*writepage)(page, wbc, data); | |
2090 | ||
2091 | if (unlikely(ret == AOP_WRITEPAGE_ACTIVATE)) { | |
2092 | unlock_page(page); | |
2093 | ret = 0; | |
2094 | } | |
2095 | if (ret || (--(wbc->nr_to_write) <= 0)) | |
2096 | done = 1; | |
2097 | if (wbc->nonblocking && bdi_write_congested(bdi)) { | |
2098 | wbc->encountered_congestion = 1; | |
2099 | done = 1; | |
2100 | } | |
2101 | } | |
2102 | pagevec_release(&pvec); | |
2103 | cond_resched(); | |
2104 | } | |
2105 | if (!scanned && !done) { | |
2106 | /* | |
2107 | * We hit the last page and there is more work to be done: wrap | |
2108 | * back to the start of the file | |
2109 | */ | |
2110 | scanned = 1; | |
2111 | index = 0; | |
2112 | goto retry; | |
2113 | } | |
2114 | if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0)) | |
2115 | mapping->writeback_index = index; | |
2116 | return ret; | |
2117 | } | |
2118 | #endif | |
2119 | ||
b293f02e CM |
2120 | int extent_write_full_page(struct extent_map_tree *tree, struct page *page, |
2121 | get_extent_t *get_extent, | |
2122 | struct writeback_control *wbc) | |
2123 | { | |
2124 | int ret; | |
015a739c | 2125 | struct address_space *mapping = page->mapping; |
b293f02e CM |
2126 | struct extent_page_data epd = { |
2127 | .bio = NULL, | |
2128 | .tree = tree, | |
2129 | .get_extent = get_extent, | |
2130 | }; | |
015a739c CM |
2131 | struct writeback_control wbc_writepages = { |
2132 | .bdi = wbc->bdi, | |
2133 | .sync_mode = WB_SYNC_NONE, | |
2134 | .older_than_this = NULL, | |
2135 | .nr_to_write = 64, | |
2136 | .range_start = page_offset(page) + PAGE_CACHE_SIZE, | |
2137 | .range_end = (loff_t)-1, | |
2138 | }; | |
2139 | ||
b293f02e CM |
2140 | |
2141 | ret = __extent_writepage(page, wbc, &epd); | |
015a739c CM |
2142 | |
2143 | write_cache_pages(mapping, &wbc_writepages, __extent_writepage, &epd); | |
6da6abae | 2144 | if (epd.bio) { |
b293f02e | 2145 | submit_one_bio(WRITE, epd.bio); |
6da6abae | 2146 | } |
b293f02e CM |
2147 | return ret; |
2148 | } | |
a52d9a80 CM |
2149 | EXPORT_SYMBOL(extent_write_full_page); |
2150 | ||
6da6abae | 2151 | |
b293f02e CM |
2152 | int extent_writepages(struct extent_map_tree *tree, |
2153 | struct address_space *mapping, | |
2154 | get_extent_t *get_extent, | |
2155 | struct writeback_control *wbc) | |
2156 | { | |
6da6abae | 2157 | int ret = 0; |
b293f02e CM |
2158 | struct extent_page_data epd = { |
2159 | .bio = NULL, | |
2160 | .tree = tree, | |
2161 | .get_extent = get_extent, | |
2162 | }; | |
2163 | ||
2164 | ret = write_cache_pages(mapping, wbc, __extent_writepage, &epd); | |
6da6abae | 2165 | if (epd.bio) { |
b293f02e | 2166 | submit_one_bio(WRITE, epd.bio); |
6da6abae | 2167 | } |
b293f02e CM |
2168 | return ret; |
2169 | } | |
2170 | EXPORT_SYMBOL(extent_writepages); | |
2171 | ||
3ab2fb5a CM |
2172 | int extent_readpages(struct extent_map_tree *tree, |
2173 | struct address_space *mapping, | |
2174 | struct list_head *pages, unsigned nr_pages, | |
2175 | get_extent_t get_extent) | |
2176 | { | |
2177 | struct bio *bio = NULL; | |
2178 | unsigned page_idx; | |
2179 | struct pagevec pvec; | |
2180 | ||
2181 | pagevec_init(&pvec, 0); | |
2182 | for (page_idx = 0; page_idx < nr_pages; page_idx++) { | |
2183 | struct page *page = list_entry(pages->prev, struct page, lru); | |
2184 | ||
2185 | prefetchw(&page->flags); | |
2186 | list_del(&page->lru); | |
2187 | /* | |
2188 | * what we want to do here is call add_to_page_cache_lru, | |
2189 | * but that isn't exported, so we reproduce it here | |
2190 | */ | |
2191 | if (!add_to_page_cache(page, mapping, | |
2192 | page->index, GFP_KERNEL)) { | |
2193 | ||
2194 | /* open coding of lru_cache_add, also not exported */ | |
2195 | page_cache_get(page); | |
2196 | if (!pagevec_add(&pvec, page)) | |
2197 | __pagevec_lru_add(&pvec); | |
2198 | __extent_read_full_page(tree, page, get_extent, &bio); | |
2199 | } | |
2200 | page_cache_release(page); | |
2201 | } | |
2202 | if (pagevec_count(&pvec)) | |
2203 | __pagevec_lru_add(&pvec); | |
2204 | BUG_ON(!list_empty(pages)); | |
2205 | if (bio) | |
2206 | submit_one_bio(READ, bio); | |
2207 | return 0; | |
2208 | } | |
2209 | EXPORT_SYMBOL(extent_readpages); | |
2210 | ||
a52d9a80 CM |
2211 | /* |
2212 | * basic invalidatepage code, this waits on any locked or writeback | |
2213 | * ranges corresponding to the page, and then deletes any extent state | |
2214 | * records from the tree | |
2215 | */ | |
2216 | int extent_invalidatepage(struct extent_map_tree *tree, | |
2217 | struct page *page, unsigned long offset) | |
2218 | { | |
35ebb934 | 2219 | u64 start = ((u64)page->index << PAGE_CACHE_SHIFT); |
a52d9a80 CM |
2220 | u64 end = start + PAGE_CACHE_SIZE - 1; |
2221 | size_t blocksize = page->mapping->host->i_sb->s_blocksize; | |
2222 | ||
2223 | start += (offset + blocksize -1) & ~(blocksize - 1); | |
2224 | if (start > end) | |
2225 | return 0; | |
2226 | ||
2227 | lock_extent(tree, start, end, GFP_NOFS); | |
2228 | wait_on_extent_writeback(tree, start, end); | |
2bf5a725 CM |
2229 | clear_extent_bit(tree, start, end, |
2230 | EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC, | |
a52d9a80 CM |
2231 | 1, 1, GFP_NOFS); |
2232 | return 0; | |
2233 | } | |
2234 | EXPORT_SYMBOL(extent_invalidatepage); | |
2235 | ||
2236 | /* | |
2237 | * simple commit_write call, set_range_dirty is used to mark both | |
2238 | * the pages and the extent records as dirty | |
2239 | */ | |
2240 | int extent_commit_write(struct extent_map_tree *tree, | |
2241 | struct inode *inode, struct page *page, | |
2242 | unsigned from, unsigned to) | |
2243 | { | |
2244 | loff_t pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to; | |
2245 | ||
b3cfa35a | 2246 | set_page_extent_mapped(page); |
a52d9a80 CM |
2247 | set_page_dirty(page); |
2248 | ||
2249 | if (pos > inode->i_size) { | |
2250 | i_size_write(inode, pos); | |
2251 | mark_inode_dirty(inode); | |
2252 | } | |
2253 | return 0; | |
2254 | } | |
2255 | EXPORT_SYMBOL(extent_commit_write); | |
2256 | ||
2257 | int extent_prepare_write(struct extent_map_tree *tree, | |
2258 | struct inode *inode, struct page *page, | |
2259 | unsigned from, unsigned to, get_extent_t *get_extent) | |
2260 | { | |
35ebb934 | 2261 | u64 page_start = (u64)page->index << PAGE_CACHE_SHIFT; |
a52d9a80 CM |
2262 | u64 page_end = page_start + PAGE_CACHE_SIZE - 1; |
2263 | u64 block_start; | |
2264 | u64 orig_block_start; | |
2265 | u64 block_end; | |
2266 | u64 cur_end; | |
2267 | struct extent_map *em; | |
2268 | unsigned blocksize = 1 << inode->i_blkbits; | |
2269 | size_t page_offset = 0; | |
2270 | size_t block_off_start; | |
2271 | size_t block_off_end; | |
2272 | int err = 0; | |
2273 | int iocount = 0; | |
2274 | int ret = 0; | |
2275 | int isnew; | |
2276 | ||
b3cfa35a CH |
2277 | set_page_extent_mapped(page); |
2278 | ||
a52d9a80 CM |
2279 | block_start = (page_start + from) & ~((u64)blocksize - 1); |
2280 | block_end = (page_start + to - 1) | (blocksize - 1); | |
2281 | orig_block_start = block_start; | |
2282 | ||
2283 | lock_extent(tree, page_start, page_end, GFP_NOFS); | |
2284 | while(block_start <= block_end) { | |
2285 | em = get_extent(inode, page, page_offset, block_start, | |
2286 | block_end, 1); | |
2287 | if (IS_ERR(em) || !em) { | |
2288 | goto err; | |
2289 | } | |
2290 | cur_end = min(block_end, em->end); | |
2291 | block_off_start = block_start & (PAGE_CACHE_SIZE - 1); | |
2292 | block_off_end = block_off_start + blocksize; | |
2293 | isnew = clear_extent_new(tree, block_start, cur_end, GFP_NOFS); | |
2294 | ||
2295 | if (!PageUptodate(page) && isnew && | |
2296 | (block_off_end > to || block_off_start < from)) { | |
2297 | void *kaddr; | |
2298 | ||
2299 | kaddr = kmap_atomic(page, KM_USER0); | |
2300 | if (block_off_end > to) | |
2301 | memset(kaddr + to, 0, block_off_end - to); | |
2302 | if (block_off_start < from) | |
2303 | memset(kaddr + block_off_start, 0, | |
2304 | from - block_off_start); | |
2305 | flush_dcache_page(page); | |
2306 | kunmap_atomic(kaddr, KM_USER0); | |
2307 | } | |
6da6abae | 2308 | if ((em->block_start != EXTENT_MAP_HOLE && |
5d4fb734 | 2309 | em->block_start != EXTENT_MAP_INLINE) && |
6da6abae | 2310 | !isnew && !PageUptodate(page) && |
a52d9a80 CM |
2311 | (block_off_end > to || block_off_start < from) && |
2312 | !test_range_bit(tree, block_start, cur_end, | |
2313 | EXTENT_UPTODATE, 1)) { | |
2314 | u64 sector; | |
2315 | u64 extent_offset = block_start - em->start; | |
2316 | size_t iosize; | |
2317 | sector = (em->block_start + extent_offset) >> 9; | |
5d4fb734 | 2318 | iosize = (cur_end - block_start + blocksize) & |
a52d9a80 CM |
2319 | ~((u64)blocksize - 1); |
2320 | /* | |
2321 | * we've already got the extent locked, but we | |
2322 | * need to split the state such that our end_bio | |
2323 | * handler can clear the lock. | |
2324 | */ | |
2325 | set_extent_bit(tree, block_start, | |
2326 | block_start + iosize - 1, | |
2327 | EXTENT_LOCKED, 0, NULL, GFP_NOFS); | |
2328 | ret = submit_extent_page(READ, tree, page, | |
2329 | sector, iosize, page_offset, em->bdev, | |
b293f02e | 2330 | NULL, 1, |
a52d9a80 CM |
2331 | end_bio_extent_preparewrite); |
2332 | iocount++; | |
2333 | block_start = block_start + iosize; | |
2334 | } else { | |
2335 | set_extent_uptodate(tree, block_start, cur_end, | |
2336 | GFP_NOFS); | |
2337 | unlock_extent(tree, block_start, cur_end, GFP_NOFS); | |
2338 | block_start = cur_end + 1; | |
2339 | } | |
2340 | page_offset = block_start & (PAGE_CACHE_SIZE - 1); | |
2341 | free_extent_map(em); | |
2342 | } | |
2343 | if (iocount) { | |
2344 | wait_extent_bit(tree, orig_block_start, | |
2345 | block_end, EXTENT_LOCKED); | |
2346 | } | |
2347 | check_page_uptodate(tree, page); | |
2348 | err: | |
2349 | /* FIXME, zero out newly allocated blocks on error */ | |
2350 | return err; | |
2351 | } | |
2352 | EXPORT_SYMBOL(extent_prepare_write); | |
2353 | ||
2354 | /* | |
2355 | * a helper for releasepage. As long as there are no locked extents | |
2356 | * in the range corresponding to the page, both state records and extent | |
2357 | * map records are removed | |
2358 | */ | |
2359 | int try_release_extent_mapping(struct extent_map_tree *tree, struct page *page) | |
2360 | { | |
2361 | struct extent_map *em; | |
35ebb934 | 2362 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; |
a52d9a80 CM |
2363 | u64 end = start + PAGE_CACHE_SIZE - 1; |
2364 | u64 orig_start = start; | |
b888db2b | 2365 | int ret = 1; |
a52d9a80 CM |
2366 | |
2367 | while (start <= end) { | |
2368 | em = lookup_extent_mapping(tree, start, end); | |
2369 | if (!em || IS_ERR(em)) | |
2370 | break; | |
b888db2b CM |
2371 | if (!test_range_bit(tree, em->start, em->end, |
2372 | EXTENT_LOCKED, 0)) { | |
2373 | remove_extent_mapping(tree, em); | |
2374 | /* once for the rb tree */ | |
a52d9a80 | 2375 | free_extent_map(em); |
a52d9a80 | 2376 | } |
a52d9a80 | 2377 | start = em->end + 1; |
a52d9a80 CM |
2378 | /* once for us */ |
2379 | free_extent_map(em); | |
2380 | } | |
b888db2b CM |
2381 | if (test_range_bit(tree, orig_start, end, EXTENT_LOCKED, 0)) |
2382 | ret = 0; | |
2383 | else | |
2384 | clear_extent_bit(tree, orig_start, end, EXTENT_UPTODATE, | |
2385 | 1, 1, GFP_NOFS); | |
2386 | return ret; | |
a52d9a80 CM |
2387 | } |
2388 | EXPORT_SYMBOL(try_release_extent_mapping); | |
2389 | ||
d396c6f5 CH |
2390 | sector_t extent_bmap(struct address_space *mapping, sector_t iblock, |
2391 | get_extent_t *get_extent) | |
2392 | { | |
2393 | struct inode *inode = mapping->host; | |
2394 | u64 start = iblock << inode->i_blkbits; | |
2395 | u64 end = start + (1 << inode->i_blkbits) - 1; | |
c67cda17 | 2396 | sector_t sector = 0; |
d396c6f5 CH |
2397 | struct extent_map *em; |
2398 | ||
2399 | em = get_extent(inode, NULL, 0, start, end, 0); | |
2400 | if (!em || IS_ERR(em)) | |
2401 | return 0; | |
2402 | ||
d396c6f5 | 2403 | if (em->block_start == EXTENT_MAP_INLINE || |
5f39d397 | 2404 | em->block_start == EXTENT_MAP_HOLE) |
c67cda17 | 2405 | goto out; |
d396c6f5 | 2406 | |
c67cda17 Y |
2407 | sector = (em->block_start + start - em->start) >> inode->i_blkbits; |
2408 | out: | |
2409 | free_extent_map(em); | |
2410 | return sector; | |
d396c6f5 | 2411 | } |
5f39d397 | 2412 | |
4dc11904 | 2413 | static int add_lru(struct extent_map_tree *tree, struct extent_buffer *eb) |
6d36dcd4 | 2414 | { |
4dc11904 CM |
2415 | if (list_empty(&eb->lru)) { |
2416 | extent_buffer_get(eb); | |
2417 | list_add(&eb->lru, &tree->buffer_lru); | |
2418 | tree->lru_size++; | |
2419 | if (tree->lru_size >= BUFFER_LRU_MAX) { | |
2420 | struct extent_buffer *rm; | |
2421 | rm = list_entry(tree->buffer_lru.prev, | |
2422 | struct extent_buffer, lru); | |
2423 | tree->lru_size--; | |
856bf3e5 | 2424 | list_del_init(&rm->lru); |
4dc11904 CM |
2425 | free_extent_buffer(rm); |
2426 | } | |
2427 | } else | |
2428 | list_move(&eb->lru, &tree->buffer_lru); | |
2429 | return 0; | |
2430 | } | |
2431 | static struct extent_buffer *find_lru(struct extent_map_tree *tree, | |
2432 | u64 start, unsigned long len) | |
2433 | { | |
2434 | struct list_head *lru = &tree->buffer_lru; | |
2435 | struct list_head *cur = lru->next; | |
2436 | struct extent_buffer *eb; | |
f510cfec | 2437 | |
4dc11904 CM |
2438 | if (list_empty(lru)) |
2439 | return NULL; | |
f510cfec | 2440 | |
4dc11904 CM |
2441 | do { |
2442 | eb = list_entry(cur, struct extent_buffer, lru); | |
2443 | if (eb->start == start && eb->len == len) { | |
2444 | extent_buffer_get(eb); | |
2445 | return eb; | |
2446 | } | |
2447 | cur = cur->next; | |
2448 | } while (cur != lru); | |
2449 | return NULL; | |
6d36dcd4 CM |
2450 | } |
2451 | ||
4dc11904 | 2452 | static inline unsigned long num_extent_pages(u64 start, u64 len) |
6d36dcd4 | 2453 | { |
4dc11904 CM |
2454 | return ((start + len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT) - |
2455 | (start >> PAGE_CACHE_SHIFT); | |
6d36dcd4 CM |
2456 | } |
2457 | ||
4dc11904 CM |
2458 | static inline struct page *extent_buffer_page(struct extent_buffer *eb, |
2459 | unsigned long i) | |
6d36dcd4 CM |
2460 | { |
2461 | struct page *p; | |
3685f791 | 2462 | struct address_space *mapping; |
db94535d | 2463 | |
4dc11904 | 2464 | if (i == 0) |
810191ff | 2465 | return eb->first_page; |
6d36dcd4 | 2466 | i += eb->start >> PAGE_CACHE_SHIFT; |
3685f791 CM |
2467 | mapping = eb->first_page->mapping; |
2468 | read_lock_irq(&mapping->tree_lock); | |
2469 | p = radix_tree_lookup(&mapping->page_tree, i); | |
2470 | read_unlock_irq(&mapping->tree_lock); | |
6d36dcd4 CM |
2471 | return p; |
2472 | } | |
2473 | ||
4dc11904 CM |
2474 | static struct extent_buffer *__alloc_extent_buffer(struct extent_map_tree *tree, |
2475 | u64 start, | |
2476 | unsigned long len, | |
2477 | gfp_t mask) | |
db94535d | 2478 | { |
4dc11904 CM |
2479 | struct extent_buffer *eb = NULL; |
2480 | ||
2481 | spin_lock(&tree->lru_lock); | |
2482 | eb = find_lru(tree, start, len); | |
4dc11904 | 2483 | spin_unlock(&tree->lru_lock); |
4dc11904 | 2484 | if (eb) { |
09be207d | 2485 | return eb; |
4dc11904 | 2486 | } |
09be207d CM |
2487 | |
2488 | eb = kmem_cache_zalloc(extent_buffer_cache, mask); | |
4dc11904 CM |
2489 | INIT_LIST_HEAD(&eb->lru); |
2490 | eb->start = start; | |
2491 | eb->len = len; | |
2492 | atomic_set(&eb->refs, 1); | |
2493 | ||
4dc11904 CM |
2494 | return eb; |
2495 | } | |
2496 | ||
2497 | static void __free_extent_buffer(struct extent_buffer *eb) | |
2498 | { | |
2499 | kmem_cache_free(extent_buffer_cache, eb); | |
db94535d | 2500 | } |
4dc11904 | 2501 | |
5f39d397 CM |
2502 | struct extent_buffer *alloc_extent_buffer(struct extent_map_tree *tree, |
2503 | u64 start, unsigned long len, | |
19c00ddc | 2504 | struct page *page0, |
5f39d397 CM |
2505 | gfp_t mask) |
2506 | { | |
db94535d | 2507 | unsigned long num_pages = num_extent_pages(start, len); |
5f39d397 CM |
2508 | unsigned long i; |
2509 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
2510 | struct extent_buffer *eb; | |
2511 | struct page *p; | |
2512 | struct address_space *mapping = tree->mapping; | |
65555a06 | 2513 | int uptodate = 1; |
5f39d397 | 2514 | |
4dc11904 | 2515 | eb = __alloc_extent_buffer(tree, start, len, mask); |
5f39d397 CM |
2516 | if (!eb || IS_ERR(eb)) |
2517 | return NULL; | |
2518 | ||
4dc11904 | 2519 | if (eb->flags & EXTENT_BUFFER_FILLED) |
09be207d | 2520 | goto lru_add; |
5f39d397 | 2521 | |
19c00ddc CM |
2522 | if (page0) { |
2523 | eb->first_page = page0; | |
2524 | i = 1; | |
2525 | index++; | |
2526 | page_cache_get(page0); | |
ff79f819 | 2527 | mark_page_accessed(page0); |
19c00ddc | 2528 | set_page_extent_mapped(page0); |
0591fb56 | 2529 | WARN_ON(!PageUptodate(page0)); |
55c69072 | 2530 | set_page_extent_head(page0, len); |
19c00ddc CM |
2531 | } else { |
2532 | i = 0; | |
2533 | } | |
2534 | for (; i < num_pages; i++, index++) { | |
5f39d397 | 2535 | p = find_or_create_page(mapping, index, mask | __GFP_HIGHMEM); |
6d36dcd4 | 2536 | if (!p) { |
db94535d | 2537 | WARN_ON(1); |
5f39d397 | 2538 | goto fail; |
6d36dcd4 | 2539 | } |
f510cfec | 2540 | set_page_extent_mapped(p); |
ff79f819 | 2541 | mark_page_accessed(p); |
19c00ddc | 2542 | if (i == 0) { |
810191ff | 2543 | eb->first_page = p; |
55c69072 | 2544 | set_page_extent_head(p, len); |
19c00ddc CM |
2545 | } else { |
2546 | set_page_private(p, EXTENT_PAGE_PRIVATE); | |
2547 | } | |
5f39d397 CM |
2548 | if (!PageUptodate(p)) |
2549 | uptodate = 0; | |
2550 | unlock_page(p); | |
2551 | } | |
2552 | if (uptodate) | |
2553 | eb->flags |= EXTENT_UPTODATE; | |
4dc11904 | 2554 | eb->flags |= EXTENT_BUFFER_FILLED; |
09be207d CM |
2555 | |
2556 | lru_add: | |
2557 | spin_lock(&tree->lru_lock); | |
2558 | add_lru(tree, eb); | |
2559 | spin_unlock(&tree->lru_lock); | |
5f39d397 | 2560 | return eb; |
09be207d | 2561 | |
5f39d397 | 2562 | fail: |
856bf3e5 CM |
2563 | spin_lock(&tree->lru_lock); |
2564 | list_del_init(&eb->lru); | |
2565 | spin_unlock(&tree->lru_lock); | |
09be207d CM |
2566 | if (!atomic_dec_and_test(&eb->refs)) |
2567 | return NULL; | |
0591fb56 | 2568 | for (index = 1; index < i; index++) { |
09be207d CM |
2569 | page_cache_release(extent_buffer_page(eb, index)); |
2570 | } | |
0591fb56 CM |
2571 | if (i > 0) |
2572 | page_cache_release(extent_buffer_page(eb, 0)); | |
09be207d | 2573 | __free_extent_buffer(eb); |
5f39d397 CM |
2574 | return NULL; |
2575 | } | |
2576 | EXPORT_SYMBOL(alloc_extent_buffer); | |
2577 | ||
2578 | struct extent_buffer *find_extent_buffer(struct extent_map_tree *tree, | |
2579 | u64 start, unsigned long len, | |
2580 | gfp_t mask) | |
2581 | { | |
db94535d | 2582 | unsigned long num_pages = num_extent_pages(start, len); |
09be207d CM |
2583 | unsigned long i; |
2584 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
5f39d397 CM |
2585 | struct extent_buffer *eb; |
2586 | struct page *p; | |
2587 | struct address_space *mapping = tree->mapping; | |
14048ed0 | 2588 | int uptodate = 1; |
5f39d397 | 2589 | |
4dc11904 | 2590 | eb = __alloc_extent_buffer(tree, start, len, mask); |
5f39d397 CM |
2591 | if (!eb || IS_ERR(eb)) |
2592 | return NULL; | |
2593 | ||
4dc11904 | 2594 | if (eb->flags & EXTENT_BUFFER_FILLED) |
09be207d | 2595 | goto lru_add; |
5f39d397 CM |
2596 | |
2597 | for (i = 0; i < num_pages; i++, index++) { | |
14048ed0 | 2598 | p = find_lock_page(mapping, index); |
6d36dcd4 | 2599 | if (!p) { |
5f39d397 | 2600 | goto fail; |
6d36dcd4 | 2601 | } |
f510cfec | 2602 | set_page_extent_mapped(p); |
ff79f819 | 2603 | mark_page_accessed(p); |
19c00ddc CM |
2604 | |
2605 | if (i == 0) { | |
810191ff | 2606 | eb->first_page = p; |
55c69072 | 2607 | set_page_extent_head(p, len); |
19c00ddc CM |
2608 | } else { |
2609 | set_page_private(p, EXTENT_PAGE_PRIVATE); | |
2610 | } | |
2611 | ||
14048ed0 CM |
2612 | if (!PageUptodate(p)) |
2613 | uptodate = 0; | |
2614 | unlock_page(p); | |
5f39d397 | 2615 | } |
14048ed0 CM |
2616 | if (uptodate) |
2617 | eb->flags |= EXTENT_UPTODATE; | |
4dc11904 | 2618 | eb->flags |= EXTENT_BUFFER_FILLED; |
09be207d CM |
2619 | |
2620 | lru_add: | |
2621 | spin_lock(&tree->lru_lock); | |
2622 | add_lru(tree, eb); | |
2623 | spin_unlock(&tree->lru_lock); | |
5f39d397 CM |
2624 | return eb; |
2625 | fail: | |
856bf3e5 CM |
2626 | spin_lock(&tree->lru_lock); |
2627 | list_del_init(&eb->lru); | |
2628 | spin_unlock(&tree->lru_lock); | |
09be207d CM |
2629 | if (!atomic_dec_and_test(&eb->refs)) |
2630 | return NULL; | |
0591fb56 | 2631 | for (index = 1; index < i; index++) { |
09be207d CM |
2632 | page_cache_release(extent_buffer_page(eb, index)); |
2633 | } | |
0591fb56 CM |
2634 | if (i > 0) |
2635 | page_cache_release(extent_buffer_page(eb, 0)); | |
09be207d | 2636 | __free_extent_buffer(eb); |
5f39d397 CM |
2637 | return NULL; |
2638 | } | |
2639 | EXPORT_SYMBOL(find_extent_buffer); | |
2640 | ||
2641 | void free_extent_buffer(struct extent_buffer *eb) | |
2642 | { | |
2643 | unsigned long i; | |
2644 | unsigned long num_pages; | |
2645 | ||
2646 | if (!eb) | |
2647 | return; | |
2648 | ||
2649 | if (!atomic_dec_and_test(&eb->refs)) | |
2650 | return; | |
2651 | ||
0591fb56 | 2652 | WARN_ON(!list_empty(&eb->lru)); |
db94535d | 2653 | num_pages = num_extent_pages(eb->start, eb->len); |
5f39d397 | 2654 | |
0591fb56 | 2655 | for (i = 1; i < num_pages; i++) { |
6d36dcd4 | 2656 | page_cache_release(extent_buffer_page(eb, i)); |
5f39d397 | 2657 | } |
0591fb56 | 2658 | page_cache_release(extent_buffer_page(eb, 0)); |
6d36dcd4 | 2659 | __free_extent_buffer(eb); |
5f39d397 CM |
2660 | } |
2661 | EXPORT_SYMBOL(free_extent_buffer); | |
2662 | ||
2663 | int clear_extent_buffer_dirty(struct extent_map_tree *tree, | |
2664 | struct extent_buffer *eb) | |
2665 | { | |
2666 | int set; | |
2667 | unsigned long i; | |
2668 | unsigned long num_pages; | |
2669 | struct page *page; | |
2670 | ||
2671 | u64 start = eb->start; | |
2672 | u64 end = start + eb->len - 1; | |
2673 | ||
2674 | set = clear_extent_dirty(tree, start, end, GFP_NOFS); | |
db94535d | 2675 | num_pages = num_extent_pages(eb->start, eb->len); |
5f39d397 CM |
2676 | |
2677 | for (i = 0; i < num_pages; i++) { | |
6d36dcd4 | 2678 | page = extent_buffer_page(eb, i); |
5f39d397 | 2679 | lock_page(page); |
55c69072 CM |
2680 | if (i == 0) |
2681 | set_page_extent_head(page, eb->len); | |
2682 | else | |
2683 | set_page_private(page, EXTENT_PAGE_PRIVATE); | |
2684 | ||
5f39d397 CM |
2685 | /* |
2686 | * if we're on the last page or the first page and the | |
2687 | * block isn't aligned on a page boundary, do extra checks | |
2688 | * to make sure we don't clean page that is partially dirty | |
2689 | */ | |
2690 | if ((i == 0 && (eb->start & (PAGE_CACHE_SIZE - 1))) || | |
2691 | ((i == num_pages - 1) && | |
65555a06 | 2692 | ((eb->start + eb->len) & (PAGE_CACHE_SIZE - 1)))) { |
35ebb934 | 2693 | start = (u64)page->index << PAGE_CACHE_SHIFT; |
5f39d397 CM |
2694 | end = start + PAGE_CACHE_SIZE - 1; |
2695 | if (test_range_bit(tree, start, end, | |
2696 | EXTENT_DIRTY, 0)) { | |
2697 | unlock_page(page); | |
2698 | continue; | |
2699 | } | |
2700 | } | |
2701 | clear_page_dirty_for_io(page); | |
7073c8e8 CM |
2702 | write_lock_irq(&page->mapping->tree_lock); |
2703 | if (!PageDirty(page)) { | |
2704 | radix_tree_tag_clear(&page->mapping->page_tree, | |
2705 | page_index(page), | |
2706 | PAGECACHE_TAG_DIRTY); | |
2707 | } | |
2708 | write_unlock_irq(&page->mapping->tree_lock); | |
5f39d397 CM |
2709 | unlock_page(page); |
2710 | } | |
2711 | return 0; | |
2712 | } | |
2713 | EXPORT_SYMBOL(clear_extent_buffer_dirty); | |
2714 | ||
2715 | int wait_on_extent_buffer_writeback(struct extent_map_tree *tree, | |
2716 | struct extent_buffer *eb) | |
2717 | { | |
2718 | return wait_on_extent_writeback(tree, eb->start, | |
2719 | eb->start + eb->len - 1); | |
2720 | } | |
2721 | EXPORT_SYMBOL(wait_on_extent_buffer_writeback); | |
2722 | ||
2723 | int set_extent_buffer_dirty(struct extent_map_tree *tree, | |
2724 | struct extent_buffer *eb) | |
2725 | { | |
810191ff CM |
2726 | unsigned long i; |
2727 | unsigned long num_pages; | |
2728 | ||
2729 | num_pages = num_extent_pages(eb->start, eb->len); | |
2730 | for (i = 0; i < num_pages; i++) { | |
19c00ddc CM |
2731 | struct page *page = extent_buffer_page(eb, i); |
2732 | /* writepage may need to do something special for the | |
2733 | * first page, we have to make sure page->private is | |
2734 | * properly set. releasepage may drop page->private | |
2735 | * on us if the page isn't already dirty. | |
2736 | */ | |
2737 | if (i == 0) { | |
2738 | lock_page(page); | |
55c69072 CM |
2739 | set_page_extent_head(page, eb->len); |
2740 | } else if (PagePrivate(page) && | |
2741 | page->private != EXTENT_PAGE_PRIVATE) { | |
2742 | lock_page(page); | |
2743 | set_page_extent_mapped(page); | |
2744 | unlock_page(page); | |
19c00ddc | 2745 | } |
810191ff | 2746 | __set_page_dirty_nobuffers(extent_buffer_page(eb, i)); |
19c00ddc CM |
2747 | if (i == 0) |
2748 | unlock_page(page); | |
810191ff CM |
2749 | } |
2750 | return set_extent_dirty(tree, eb->start, | |
2751 | eb->start + eb->len - 1, GFP_NOFS); | |
5f39d397 CM |
2752 | } |
2753 | EXPORT_SYMBOL(set_extent_buffer_dirty); | |
2754 | ||
2755 | int set_extent_buffer_uptodate(struct extent_map_tree *tree, | |
2756 | struct extent_buffer *eb) | |
2757 | { | |
2758 | unsigned long i; | |
2759 | struct page *page; | |
2760 | unsigned long num_pages; | |
2761 | ||
db94535d | 2762 | num_pages = num_extent_pages(eb->start, eb->len); |
5f39d397 CM |
2763 | |
2764 | set_extent_uptodate(tree, eb->start, eb->start + eb->len - 1, | |
2765 | GFP_NOFS); | |
2766 | for (i = 0; i < num_pages; i++) { | |
6d36dcd4 | 2767 | page = extent_buffer_page(eb, i); |
5f39d397 CM |
2768 | if ((i == 0 && (eb->start & (PAGE_CACHE_SIZE - 1))) || |
2769 | ((i == num_pages - 1) && | |
65555a06 | 2770 | ((eb->start + eb->len) & (PAGE_CACHE_SIZE - 1)))) { |
5f39d397 CM |
2771 | check_page_uptodate(tree, page); |
2772 | continue; | |
2773 | } | |
2774 | SetPageUptodate(page); | |
2775 | } | |
2776 | return 0; | |
2777 | } | |
2778 | EXPORT_SYMBOL(set_extent_buffer_uptodate); | |
2779 | ||
2780 | int extent_buffer_uptodate(struct extent_map_tree *tree, | |
2781 | struct extent_buffer *eb) | |
2782 | { | |
2783 | if (eb->flags & EXTENT_UPTODATE) | |
2784 | return 1; | |
2785 | return test_range_bit(tree, eb->start, eb->start + eb->len - 1, | |
2786 | EXTENT_UPTODATE, 1); | |
2787 | } | |
2788 | EXPORT_SYMBOL(extent_buffer_uptodate); | |
2789 | ||
2790 | int read_extent_buffer_pages(struct extent_map_tree *tree, | |
19c00ddc CM |
2791 | struct extent_buffer *eb, |
2792 | u64 start, | |
2793 | int wait) | |
5f39d397 CM |
2794 | { |
2795 | unsigned long i; | |
19c00ddc | 2796 | unsigned long start_i; |
5f39d397 CM |
2797 | struct page *page; |
2798 | int err; | |
2799 | int ret = 0; | |
2800 | unsigned long num_pages; | |
2801 | ||
2802 | if (eb->flags & EXTENT_UPTODATE) | |
2803 | return 0; | |
2804 | ||
14048ed0 | 2805 | if (0 && test_range_bit(tree, eb->start, eb->start + eb->len - 1, |
5f39d397 CM |
2806 | EXTENT_UPTODATE, 1)) { |
2807 | return 0; | |
2808 | } | |
0591fb56 | 2809 | |
19c00ddc CM |
2810 | if (start) { |
2811 | WARN_ON(start < eb->start); | |
2812 | start_i = (start >> PAGE_CACHE_SHIFT) - | |
2813 | (eb->start >> PAGE_CACHE_SHIFT); | |
2814 | } else { | |
2815 | start_i = 0; | |
2816 | } | |
5f39d397 | 2817 | |
db94535d | 2818 | num_pages = num_extent_pages(eb->start, eb->len); |
19c00ddc | 2819 | for (i = start_i; i < num_pages; i++) { |
6d36dcd4 | 2820 | page = extent_buffer_page(eb, i); |
5f39d397 CM |
2821 | if (PageUptodate(page)) { |
2822 | continue; | |
2823 | } | |
2824 | if (!wait) { | |
2825 | if (TestSetPageLocked(page)) { | |
2826 | continue; | |
2827 | } | |
2828 | } else { | |
2829 | lock_page(page); | |
2830 | } | |
2831 | if (!PageUptodate(page)) { | |
2832 | err = page->mapping->a_ops->readpage(NULL, page); | |
2833 | if (err) { | |
2834 | ret = err; | |
2835 | } | |
2836 | } else { | |
2837 | unlock_page(page); | |
2838 | } | |
2839 | } | |
2840 | ||
2841 | if (ret || !wait) { | |
2842 | return ret; | |
2843 | } | |
2844 | ||
19c00ddc | 2845 | for (i = start_i; i < num_pages; i++) { |
6d36dcd4 | 2846 | page = extent_buffer_page(eb, i); |
5f39d397 CM |
2847 | wait_on_page_locked(page); |
2848 | if (!PageUptodate(page)) { | |
2849 | ret = -EIO; | |
2850 | } | |
2851 | } | |
4dc11904 CM |
2852 | if (!ret) |
2853 | eb->flags |= EXTENT_UPTODATE; | |
5f39d397 CM |
2854 | return ret; |
2855 | } | |
2856 | EXPORT_SYMBOL(read_extent_buffer_pages); | |
2857 | ||
2858 | void read_extent_buffer(struct extent_buffer *eb, void *dstv, | |
2859 | unsigned long start, | |
2860 | unsigned long len) | |
2861 | { | |
2862 | size_t cur; | |
2863 | size_t offset; | |
2864 | struct page *page; | |
2865 | char *kaddr; | |
2866 | char *dst = (char *)dstv; | |
2867 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
2868 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
14048ed0 | 2869 | unsigned long num_pages = num_extent_pages(eb->start, eb->len); |
5f39d397 CM |
2870 | |
2871 | WARN_ON(start > eb->len); | |
2872 | WARN_ON(start + len > eb->start + eb->len); | |
2873 | ||
3685f791 | 2874 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); |
5f39d397 CM |
2875 | |
2876 | while(len > 0) { | |
6d36dcd4 | 2877 | page = extent_buffer_page(eb, i); |
14048ed0 CM |
2878 | if (!PageUptodate(page)) { |
2879 | printk("page %lu not up to date i %lu, total %lu, len %lu\n", page->index, i, num_pages, eb->len); | |
2880 | WARN_ON(1); | |
2881 | } | |
5f39d397 CM |
2882 | WARN_ON(!PageUptodate(page)); |
2883 | ||
2884 | cur = min(len, (PAGE_CACHE_SIZE - offset)); | |
59d169e2 | 2885 | kaddr = kmap_atomic(page, KM_USER1); |
5f39d397 | 2886 | memcpy(dst, kaddr + offset, cur); |
59d169e2 | 2887 | kunmap_atomic(kaddr, KM_USER1); |
5f39d397 CM |
2888 | |
2889 | dst += cur; | |
2890 | len -= cur; | |
2891 | offset = 0; | |
2892 | i++; | |
5f39d397 CM |
2893 | } |
2894 | } | |
2895 | EXPORT_SYMBOL(read_extent_buffer); | |
2896 | ||
19c00ddc | 2897 | int map_private_extent_buffer(struct extent_buffer *eb, unsigned long start, |
db94535d CM |
2898 | unsigned long min_len, char **token, char **map, |
2899 | unsigned long *map_start, | |
2900 | unsigned long *map_len, int km) | |
5f39d397 | 2901 | { |
479965d6 | 2902 | size_t offset = start & (PAGE_CACHE_SIZE - 1); |
5f39d397 | 2903 | char *kaddr; |
db94535d | 2904 | struct page *p; |
5f39d397 CM |
2905 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); |
2906 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
65555a06 | 2907 | unsigned long end_i = (start_offset + start + min_len - 1) >> |
810191ff | 2908 | PAGE_CACHE_SHIFT; |
479965d6 CM |
2909 | |
2910 | if (i != end_i) | |
2911 | return -EINVAL; | |
5f39d397 | 2912 | |
5f39d397 CM |
2913 | if (i == 0) { |
2914 | offset = start_offset; | |
2915 | *map_start = 0; | |
2916 | } else { | |
db94535d | 2917 | offset = 0; |
0591fb56 | 2918 | *map_start = ((u64)i << PAGE_CACHE_SHIFT) - start_offset; |
5f39d397 | 2919 | } |
65555a06 | 2920 | if (start + min_len > eb->len) { |
19c00ddc CM |
2921 | printk("bad mapping eb start %Lu len %lu, wanted %lu %lu\n", eb->start, eb->len, start, min_len); |
2922 | WARN_ON(1); | |
2923 | } | |
5f39d397 | 2924 | |
db94535d CM |
2925 | p = extent_buffer_page(eb, i); |
2926 | WARN_ON(!PageUptodate(p)); | |
2927 | kaddr = kmap_atomic(p, km); | |
5f39d397 CM |
2928 | *token = kaddr; |
2929 | *map = kaddr + offset; | |
2930 | *map_len = PAGE_CACHE_SIZE - offset; | |
2931 | return 0; | |
2932 | } | |
19c00ddc | 2933 | EXPORT_SYMBOL(map_private_extent_buffer); |
db94535d CM |
2934 | |
2935 | int map_extent_buffer(struct extent_buffer *eb, unsigned long start, | |
2936 | unsigned long min_len, | |
2937 | char **token, char **map, | |
2938 | unsigned long *map_start, | |
2939 | unsigned long *map_len, int km) | |
2940 | { | |
2941 | int err; | |
2942 | int save = 0; | |
2943 | if (eb->map_token) { | |
db94535d CM |
2944 | unmap_extent_buffer(eb, eb->map_token, km); |
2945 | eb->map_token = NULL; | |
2946 | save = 1; | |
2947 | } | |
19c00ddc CM |
2948 | err = map_private_extent_buffer(eb, start, min_len, token, map, |
2949 | map_start, map_len, km); | |
db94535d CM |
2950 | if (!err && save) { |
2951 | eb->map_token = *token; | |
2952 | eb->kaddr = *map; | |
2953 | eb->map_start = *map_start; | |
2954 | eb->map_len = *map_len; | |
2955 | } | |
2956 | return err; | |
2957 | } | |
5f39d397 CM |
2958 | EXPORT_SYMBOL(map_extent_buffer); |
2959 | ||
2960 | void unmap_extent_buffer(struct extent_buffer *eb, char *token, int km) | |
2961 | { | |
ae5252bd | 2962 | kunmap_atomic(token, km); |
5f39d397 CM |
2963 | } |
2964 | EXPORT_SYMBOL(unmap_extent_buffer); | |
2965 | ||
2966 | int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv, | |
2967 | unsigned long start, | |
2968 | unsigned long len) | |
2969 | { | |
2970 | size_t cur; | |
2971 | size_t offset; | |
2972 | struct page *page; | |
2973 | char *kaddr; | |
2974 | char *ptr = (char *)ptrv; | |
2975 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
2976 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
2977 | int ret = 0; | |
2978 | ||
2979 | WARN_ON(start > eb->len); | |
2980 | WARN_ON(start + len > eb->start + eb->len); | |
2981 | ||
3685f791 | 2982 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); |
5f39d397 CM |
2983 | |
2984 | while(len > 0) { | |
6d36dcd4 | 2985 | page = extent_buffer_page(eb, i); |
5f39d397 CM |
2986 | WARN_ON(!PageUptodate(page)); |
2987 | ||
2988 | cur = min(len, (PAGE_CACHE_SIZE - offset)); | |
2989 | ||
ae5252bd | 2990 | kaddr = kmap_atomic(page, KM_USER0); |
5f39d397 | 2991 | ret = memcmp(ptr, kaddr + offset, cur); |
ae5252bd | 2992 | kunmap_atomic(kaddr, KM_USER0); |
5f39d397 CM |
2993 | if (ret) |
2994 | break; | |
2995 | ||
2996 | ptr += cur; | |
2997 | len -= cur; | |
2998 | offset = 0; | |
2999 | i++; | |
5f39d397 CM |
3000 | } |
3001 | return ret; | |
3002 | } | |
3003 | EXPORT_SYMBOL(memcmp_extent_buffer); | |
3004 | ||
3005 | void write_extent_buffer(struct extent_buffer *eb, const void *srcv, | |
3006 | unsigned long start, unsigned long len) | |
3007 | { | |
3008 | size_t cur; | |
3009 | size_t offset; | |
3010 | struct page *page; | |
3011 | char *kaddr; | |
3012 | char *src = (char *)srcv; | |
3013 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3014 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
3015 | ||
3016 | WARN_ON(start > eb->len); | |
3017 | WARN_ON(start + len > eb->start + eb->len); | |
3018 | ||
3685f791 | 3019 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); |
5f39d397 CM |
3020 | |
3021 | while(len > 0) { | |
6d36dcd4 | 3022 | page = extent_buffer_page(eb, i); |
5f39d397 CM |
3023 | WARN_ON(!PageUptodate(page)); |
3024 | ||
3025 | cur = min(len, PAGE_CACHE_SIZE - offset); | |
59d169e2 | 3026 | kaddr = kmap_atomic(page, KM_USER1); |
5f39d397 | 3027 | memcpy(kaddr + offset, src, cur); |
59d169e2 | 3028 | kunmap_atomic(kaddr, KM_USER1); |
5f39d397 CM |
3029 | |
3030 | src += cur; | |
3031 | len -= cur; | |
3032 | offset = 0; | |
3033 | i++; | |
5f39d397 CM |
3034 | } |
3035 | } | |
3036 | EXPORT_SYMBOL(write_extent_buffer); | |
3037 | ||
3038 | void memset_extent_buffer(struct extent_buffer *eb, char c, | |
3039 | unsigned long start, unsigned long len) | |
3040 | { | |
3041 | size_t cur; | |
3042 | size_t offset; | |
3043 | struct page *page; | |
3044 | char *kaddr; | |
3045 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3046 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
3047 | ||
3048 | WARN_ON(start > eb->len); | |
3049 | WARN_ON(start + len > eb->start + eb->len); | |
3050 | ||
3685f791 | 3051 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); |
5f39d397 CM |
3052 | |
3053 | while(len > 0) { | |
6d36dcd4 | 3054 | page = extent_buffer_page(eb, i); |
5f39d397 CM |
3055 | WARN_ON(!PageUptodate(page)); |
3056 | ||
3057 | cur = min(len, PAGE_CACHE_SIZE - offset); | |
ae5252bd | 3058 | kaddr = kmap_atomic(page, KM_USER0); |
5f39d397 | 3059 | memset(kaddr + offset, c, cur); |
ae5252bd | 3060 | kunmap_atomic(kaddr, KM_USER0); |
5f39d397 CM |
3061 | |
3062 | len -= cur; | |
3063 | offset = 0; | |
3064 | i++; | |
5f39d397 CM |
3065 | } |
3066 | } | |
3067 | EXPORT_SYMBOL(memset_extent_buffer); | |
3068 | ||
3069 | void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src, | |
3070 | unsigned long dst_offset, unsigned long src_offset, | |
3071 | unsigned long len) | |
3072 | { | |
3073 | u64 dst_len = dst->len; | |
3074 | size_t cur; | |
3075 | size_t offset; | |
3076 | struct page *page; | |
3077 | char *kaddr; | |
3078 | size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3079 | unsigned long i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT; | |
3080 | ||
3081 | WARN_ON(src->len != dst_len); | |
3082 | ||
3685f791 CM |
3083 | offset = (start_offset + dst_offset) & |
3084 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
5f39d397 CM |
3085 | |
3086 | while(len > 0) { | |
6d36dcd4 | 3087 | page = extent_buffer_page(dst, i); |
5f39d397 CM |
3088 | WARN_ON(!PageUptodate(page)); |
3089 | ||
3090 | cur = min(len, (unsigned long)(PAGE_CACHE_SIZE - offset)); | |
3091 | ||
ff190c0c | 3092 | kaddr = kmap_atomic(page, KM_USER0); |
5f39d397 | 3093 | read_extent_buffer(src, kaddr + offset, src_offset, cur); |
ff190c0c | 3094 | kunmap_atomic(kaddr, KM_USER0); |
5f39d397 CM |
3095 | |
3096 | src_offset += cur; | |
3097 | len -= cur; | |
3098 | offset = 0; | |
3099 | i++; | |
3100 | } | |
3101 | } | |
3102 | EXPORT_SYMBOL(copy_extent_buffer); | |
3103 | ||
3104 | static void move_pages(struct page *dst_page, struct page *src_page, | |
3105 | unsigned long dst_off, unsigned long src_off, | |
3106 | unsigned long len) | |
3107 | { | |
ae5252bd | 3108 | char *dst_kaddr = kmap_atomic(dst_page, KM_USER0); |
5f39d397 CM |
3109 | if (dst_page == src_page) { |
3110 | memmove(dst_kaddr + dst_off, dst_kaddr + src_off, len); | |
3111 | } else { | |
ae5252bd | 3112 | char *src_kaddr = kmap_atomic(src_page, KM_USER1); |
5f39d397 CM |
3113 | char *p = dst_kaddr + dst_off + len; |
3114 | char *s = src_kaddr + src_off + len; | |
3115 | ||
3116 | while (len--) | |
3117 | *--p = *--s; | |
3118 | ||
ae5252bd | 3119 | kunmap_atomic(src_kaddr, KM_USER1); |
5f39d397 | 3120 | } |
ae5252bd | 3121 | kunmap_atomic(dst_kaddr, KM_USER0); |
5f39d397 CM |
3122 | } |
3123 | ||
3124 | static void copy_pages(struct page *dst_page, struct page *src_page, | |
3125 | unsigned long dst_off, unsigned long src_off, | |
3126 | unsigned long len) | |
3127 | { | |
ae5252bd | 3128 | char *dst_kaddr = kmap_atomic(dst_page, KM_USER0); |
5f39d397 CM |
3129 | char *src_kaddr; |
3130 | ||
3131 | if (dst_page != src_page) | |
ae5252bd | 3132 | src_kaddr = kmap_atomic(src_page, KM_USER1); |
5f39d397 CM |
3133 | else |
3134 | src_kaddr = dst_kaddr; | |
3135 | ||
3136 | memcpy(dst_kaddr + dst_off, src_kaddr + src_off, len); | |
5f39d397 CM |
3137 | kunmap_atomic(dst_kaddr, KM_USER0); |
3138 | if (dst_page != src_page) | |
3139 | kunmap_atomic(src_kaddr, KM_USER1); | |
5f39d397 CM |
3140 | } |
3141 | ||
3142 | void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, | |
3143 | unsigned long src_offset, unsigned long len) | |
3144 | { | |
3145 | size_t cur; | |
3146 | size_t dst_off_in_page; | |
3147 | size_t src_off_in_page; | |
3148 | size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3149 | unsigned long dst_i; | |
3150 | unsigned long src_i; | |
3151 | ||
3152 | if (src_offset + len > dst->len) { | |
3153 | printk("memmove bogus src_offset %lu move len %lu len %lu\n", | |
3154 | src_offset, len, dst->len); | |
3155 | BUG_ON(1); | |
3156 | } | |
3157 | if (dst_offset + len > dst->len) { | |
3158 | printk("memmove bogus dst_offset %lu move len %lu len %lu\n", | |
3159 | dst_offset, len, dst->len); | |
3160 | BUG_ON(1); | |
3161 | } | |
3162 | ||
3163 | while(len > 0) { | |
3685f791 | 3164 | dst_off_in_page = (start_offset + dst_offset) & |
5f39d397 | 3165 | ((unsigned long)PAGE_CACHE_SIZE - 1); |
3685f791 | 3166 | src_off_in_page = (start_offset + src_offset) & |
5f39d397 CM |
3167 | ((unsigned long)PAGE_CACHE_SIZE - 1); |
3168 | ||
3169 | dst_i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT; | |
3170 | src_i = (start_offset + src_offset) >> PAGE_CACHE_SHIFT; | |
3171 | ||
5f39d397 CM |
3172 | cur = min(len, (unsigned long)(PAGE_CACHE_SIZE - |
3173 | src_off_in_page)); | |
ae2f5411 JA |
3174 | cur = min_t(unsigned long, cur, |
3175 | (unsigned long)(PAGE_CACHE_SIZE - dst_off_in_page)); | |
5f39d397 | 3176 | |
6d36dcd4 CM |
3177 | copy_pages(extent_buffer_page(dst, dst_i), |
3178 | extent_buffer_page(dst, src_i), | |
5f39d397 CM |
3179 | dst_off_in_page, src_off_in_page, cur); |
3180 | ||
3181 | src_offset += cur; | |
3182 | dst_offset += cur; | |
3183 | len -= cur; | |
3184 | } | |
3185 | } | |
3186 | EXPORT_SYMBOL(memcpy_extent_buffer); | |
3187 | ||
3188 | void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, | |
3189 | unsigned long src_offset, unsigned long len) | |
3190 | { | |
3191 | size_t cur; | |
3192 | size_t dst_off_in_page; | |
3193 | size_t src_off_in_page; | |
3194 | unsigned long dst_end = dst_offset + len - 1; | |
3195 | unsigned long src_end = src_offset + len - 1; | |
3196 | size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3197 | unsigned long dst_i; | |
3198 | unsigned long src_i; | |
3199 | ||
3200 | if (src_offset + len > dst->len) { | |
3201 | printk("memmove bogus src_offset %lu move len %lu len %lu\n", | |
3202 | src_offset, len, dst->len); | |
3203 | BUG_ON(1); | |
3204 | } | |
3205 | if (dst_offset + len > dst->len) { | |
3206 | printk("memmove bogus dst_offset %lu move len %lu len %lu\n", | |
3207 | dst_offset, len, dst->len); | |
3208 | BUG_ON(1); | |
3209 | } | |
3210 | if (dst_offset < src_offset) { | |
3211 | memcpy_extent_buffer(dst, dst_offset, src_offset, len); | |
3212 | return; | |
3213 | } | |
3214 | while(len > 0) { | |
3215 | dst_i = (start_offset + dst_end) >> PAGE_CACHE_SHIFT; | |
3216 | src_i = (start_offset + src_end) >> PAGE_CACHE_SHIFT; | |
3217 | ||
3685f791 | 3218 | dst_off_in_page = (start_offset + dst_end) & |
5f39d397 | 3219 | ((unsigned long)PAGE_CACHE_SIZE - 1); |
3685f791 | 3220 | src_off_in_page = (start_offset + src_end) & |
5f39d397 | 3221 | ((unsigned long)PAGE_CACHE_SIZE - 1); |
5f39d397 | 3222 | |
ae2f5411 | 3223 | cur = min_t(unsigned long, len, src_off_in_page + 1); |
5f39d397 | 3224 | cur = min(cur, dst_off_in_page + 1); |
6d36dcd4 CM |
3225 | move_pages(extent_buffer_page(dst, dst_i), |
3226 | extent_buffer_page(dst, src_i), | |
5f39d397 CM |
3227 | dst_off_in_page - cur + 1, |
3228 | src_off_in_page - cur + 1, cur); | |
3229 | ||
db94535d CM |
3230 | dst_end -= cur; |
3231 | src_end -= cur; | |
5f39d397 CM |
3232 | len -= cur; |
3233 | } | |
3234 | } | |
3235 | EXPORT_SYMBOL(memmove_extent_buffer); |