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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> | |
11 | #include "extent_map.h" | |
12 | ||
86479a04 CM |
13 | /* temporary define until extent_map moves out of btrfs */ |
14 | struct kmem_cache *btrfs_cache_create(const char *name, size_t size, | |
15 | unsigned long extra_flags, | |
16 | void (*ctor)(void *, struct kmem_cache *, | |
17 | unsigned long)); | |
18 | ||
a52d9a80 CM |
19 | static struct kmem_cache *extent_map_cache; |
20 | static struct kmem_cache *extent_state_cache; | |
6d36dcd4 CM |
21 | static struct kmem_cache *extent_buffer_cache; |
22 | static LIST_HEAD(extent_buffers); | |
23 | static spinlock_t extent_buffers_lock; | |
24 | static int nr_extent_buffers; | |
25 | #define MAX_EXTENT_BUFFER_CACHE 128 | |
a52d9a80 CM |
26 | |
27 | struct tree_entry { | |
28 | u64 start; | |
29 | u64 end; | |
30 | int in_tree; | |
31 | struct rb_node rb_node; | |
32 | }; | |
33 | ||
a52d9a80 CM |
34 | void __init extent_map_init(void) |
35 | { | |
86479a04 | 36 | extent_map_cache = btrfs_cache_create("extent_map", |
6d36dcd4 | 37 | sizeof(struct extent_map), 0, |
a52d9a80 | 38 | NULL); |
86479a04 | 39 | extent_state_cache = btrfs_cache_create("extent_state", |
6d36dcd4 | 40 | sizeof(struct extent_state), 0, |
a52d9a80 | 41 | NULL); |
6d36dcd4 CM |
42 | extent_buffer_cache = btrfs_cache_create("extent_buffers", |
43 | sizeof(struct extent_buffer), 0, | |
44 | NULL); | |
45 | spin_lock_init(&extent_buffers_lock); | |
a52d9a80 CM |
46 | } |
47 | ||
48 | void __exit extent_map_exit(void) | |
49 | { | |
6d36dcd4 CM |
50 | struct extent_buffer *eb; |
51 | ||
52 | while (!list_empty(&extent_buffers)) { | |
53 | eb = list_entry(extent_buffers.next, | |
54 | struct extent_buffer, list); | |
55 | list_del(&eb->list); | |
56 | kmem_cache_free(extent_buffer_cache, eb); | |
57 | } | |
a52d9a80 CM |
58 | if (extent_map_cache) |
59 | kmem_cache_destroy(extent_map_cache); | |
60 | if (extent_state_cache) | |
61 | kmem_cache_destroy(extent_state_cache); | |
6d36dcd4 CM |
62 | if (extent_buffer_cache) |
63 | kmem_cache_destroy(extent_buffer_cache); | |
a52d9a80 CM |
64 | } |
65 | ||
66 | void extent_map_tree_init(struct extent_map_tree *tree, | |
67 | struct address_space *mapping, gfp_t mask) | |
68 | { | |
69 | tree->map.rb_node = NULL; | |
70 | tree->state.rb_node = NULL; | |
07157aac | 71 | tree->ops = NULL; |
a52d9a80 CM |
72 | rwlock_init(&tree->lock); |
73 | tree->mapping = mapping; | |
74 | } | |
75 | EXPORT_SYMBOL(extent_map_tree_init); | |
76 | ||
77 | struct extent_map *alloc_extent_map(gfp_t mask) | |
78 | { | |
79 | struct extent_map *em; | |
80 | em = kmem_cache_alloc(extent_map_cache, mask); | |
81 | if (!em || IS_ERR(em)) | |
82 | return em; | |
83 | em->in_tree = 0; | |
84 | atomic_set(&em->refs, 1); | |
85 | return em; | |
86 | } | |
87 | EXPORT_SYMBOL(alloc_extent_map); | |
88 | ||
89 | void free_extent_map(struct extent_map *em) | |
90 | { | |
2bf5a725 CM |
91 | if (!em) |
92 | return; | |
a52d9a80 CM |
93 | if (atomic_dec_and_test(&em->refs)) { |
94 | WARN_ON(em->in_tree); | |
95 | kmem_cache_free(extent_map_cache, em); | |
96 | } | |
97 | } | |
98 | EXPORT_SYMBOL(free_extent_map); | |
99 | ||
100 | ||
101 | struct extent_state *alloc_extent_state(gfp_t mask) | |
102 | { | |
103 | struct extent_state *state; | |
104 | state = kmem_cache_alloc(extent_state_cache, mask); | |
105 | if (!state || IS_ERR(state)) | |
106 | return state; | |
107 | state->state = 0; | |
108 | state->in_tree = 0; | |
07157aac | 109 | state->private = 0; |
a52d9a80 CM |
110 | atomic_set(&state->refs, 1); |
111 | init_waitqueue_head(&state->wq); | |
a52d9a80 CM |
112 | return state; |
113 | } | |
114 | EXPORT_SYMBOL(alloc_extent_state); | |
115 | ||
116 | void free_extent_state(struct extent_state *state) | |
117 | { | |
2bf5a725 CM |
118 | if (!state) |
119 | return; | |
a52d9a80 CM |
120 | if (atomic_dec_and_test(&state->refs)) { |
121 | WARN_ON(state->in_tree); | |
a52d9a80 CM |
122 | kmem_cache_free(extent_state_cache, state); |
123 | } | |
124 | } | |
125 | EXPORT_SYMBOL(free_extent_state); | |
126 | ||
127 | static struct rb_node *tree_insert(struct rb_root *root, u64 offset, | |
128 | struct rb_node *node) | |
129 | { | |
130 | struct rb_node ** p = &root->rb_node; | |
131 | struct rb_node * parent = NULL; | |
132 | struct tree_entry *entry; | |
133 | ||
134 | while(*p) { | |
135 | parent = *p; | |
136 | entry = rb_entry(parent, struct tree_entry, rb_node); | |
137 | ||
138 | if (offset < entry->start) | |
139 | p = &(*p)->rb_left; | |
140 | else if (offset > entry->end) | |
141 | p = &(*p)->rb_right; | |
142 | else | |
143 | return parent; | |
144 | } | |
145 | ||
146 | entry = rb_entry(node, struct tree_entry, rb_node); | |
147 | entry->in_tree = 1; | |
148 | rb_link_node(node, parent, p); | |
149 | rb_insert_color(node, root); | |
150 | return NULL; | |
151 | } | |
152 | ||
153 | static struct rb_node *__tree_search(struct rb_root *root, u64 offset, | |
154 | struct rb_node **prev_ret) | |
155 | { | |
156 | struct rb_node * n = root->rb_node; | |
157 | struct rb_node *prev = NULL; | |
158 | struct tree_entry *entry; | |
159 | struct tree_entry *prev_entry = NULL; | |
160 | ||
161 | while(n) { | |
162 | entry = rb_entry(n, struct tree_entry, rb_node); | |
163 | prev = n; | |
164 | prev_entry = entry; | |
165 | ||
166 | if (offset < entry->start) | |
167 | n = n->rb_left; | |
168 | else if (offset > entry->end) | |
169 | n = n->rb_right; | |
170 | else | |
171 | return n; | |
172 | } | |
173 | if (!prev_ret) | |
174 | return NULL; | |
175 | while(prev && offset > prev_entry->end) { | |
176 | prev = rb_next(prev); | |
177 | prev_entry = rb_entry(prev, struct tree_entry, rb_node); | |
178 | } | |
179 | *prev_ret = prev; | |
180 | return NULL; | |
181 | } | |
182 | ||
183 | static inline struct rb_node *tree_search(struct rb_root *root, u64 offset) | |
184 | { | |
185 | struct rb_node *prev; | |
186 | struct rb_node *ret; | |
187 | ret = __tree_search(root, offset, &prev); | |
188 | if (!ret) | |
189 | return prev; | |
190 | return ret; | |
191 | } | |
192 | ||
193 | static int tree_delete(struct rb_root *root, u64 offset) | |
194 | { | |
195 | struct rb_node *node; | |
196 | struct tree_entry *entry; | |
197 | ||
198 | node = __tree_search(root, offset, NULL); | |
199 | if (!node) | |
200 | return -ENOENT; | |
201 | entry = rb_entry(node, struct tree_entry, rb_node); | |
202 | entry->in_tree = 0; | |
203 | rb_erase(node, root); | |
204 | return 0; | |
205 | } | |
206 | ||
207 | /* | |
208 | * add_extent_mapping tries a simple backward merge with existing | |
209 | * mappings. The extent_map struct passed in will be inserted into | |
210 | * the tree directly (no copies made, just a reference taken). | |
211 | */ | |
212 | int add_extent_mapping(struct extent_map_tree *tree, | |
213 | struct extent_map *em) | |
214 | { | |
215 | int ret = 0; | |
216 | struct extent_map *prev = NULL; | |
217 | struct rb_node *rb; | |
218 | ||
219 | write_lock_irq(&tree->lock); | |
220 | rb = tree_insert(&tree->map, em->end, &em->rb_node); | |
221 | if (rb) { | |
222 | prev = rb_entry(rb, struct extent_map, rb_node); | |
223 | printk("found extent map %Lu %Lu on insert of %Lu %Lu\n", prev->start, prev->end, em->start, em->end); | |
224 | ret = -EEXIST; | |
225 | goto out; | |
226 | } | |
227 | atomic_inc(&em->refs); | |
228 | if (em->start != 0) { | |
229 | rb = rb_prev(&em->rb_node); | |
230 | if (rb) | |
231 | prev = rb_entry(rb, struct extent_map, rb_node); | |
232 | if (prev && prev->end + 1 == em->start && | |
5f39d397 CM |
233 | ((em->block_start == EXTENT_MAP_HOLE && |
234 | prev->block_start == EXTENT_MAP_HOLE) || | |
a52d9a80 CM |
235 | (em->block_start == prev->block_end + 1))) { |
236 | em->start = prev->start; | |
237 | em->block_start = prev->block_start; | |
238 | rb_erase(&prev->rb_node, &tree->map); | |
239 | prev->in_tree = 0; | |
240 | free_extent_map(prev); | |
241 | } | |
242 | } | |
243 | out: | |
244 | write_unlock_irq(&tree->lock); | |
245 | return ret; | |
246 | } | |
247 | EXPORT_SYMBOL(add_extent_mapping); | |
248 | ||
249 | /* | |
250 | * lookup_extent_mapping returns the first extent_map struct in the | |
251 | * tree that intersects the [start, end] (inclusive) range. There may | |
252 | * be additional objects in the tree that intersect, so check the object | |
253 | * returned carefully to make sure you don't need additional lookups. | |
254 | */ | |
255 | struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree, | |
256 | u64 start, u64 end) | |
257 | { | |
258 | struct extent_map *em; | |
259 | struct rb_node *rb_node; | |
260 | ||
261 | read_lock_irq(&tree->lock); | |
262 | rb_node = tree_search(&tree->map, start); | |
263 | if (!rb_node) { | |
264 | em = NULL; | |
265 | goto out; | |
266 | } | |
267 | if (IS_ERR(rb_node)) { | |
268 | em = ERR_PTR(PTR_ERR(rb_node)); | |
269 | goto out; | |
270 | } | |
271 | em = rb_entry(rb_node, struct extent_map, rb_node); | |
272 | if (em->end < start || em->start > end) { | |
273 | em = NULL; | |
274 | goto out; | |
275 | } | |
276 | atomic_inc(&em->refs); | |
277 | out: | |
278 | read_unlock_irq(&tree->lock); | |
279 | return em; | |
280 | } | |
281 | EXPORT_SYMBOL(lookup_extent_mapping); | |
282 | ||
283 | /* | |
284 | * removes an extent_map struct from the tree. No reference counts are | |
285 | * dropped, and no checks are done to see if the range is in use | |
286 | */ | |
287 | int remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em) | |
288 | { | |
289 | int ret; | |
290 | ||
291 | write_lock_irq(&tree->lock); | |
292 | ret = tree_delete(&tree->map, em->end); | |
293 | write_unlock_irq(&tree->lock); | |
294 | return ret; | |
295 | } | |
296 | EXPORT_SYMBOL(remove_extent_mapping); | |
297 | ||
298 | /* | |
299 | * utility function to look for merge candidates inside a given range. | |
300 | * Any extents with matching state are merged together into a single | |
301 | * extent in the tree. Extents with EXTENT_IO in their state field | |
302 | * are not merged because the end_io handlers need to be able to do | |
303 | * operations on them without sleeping (or doing allocations/splits). | |
304 | * | |
305 | * This should be called with the tree lock held. | |
306 | */ | |
307 | static int merge_state(struct extent_map_tree *tree, | |
308 | struct extent_state *state) | |
309 | { | |
310 | struct extent_state *other; | |
311 | struct rb_node *other_node; | |
312 | ||
313 | if (state->state & EXTENT_IOBITS) | |
314 | return 0; | |
315 | ||
316 | other_node = rb_prev(&state->rb_node); | |
317 | if (other_node) { | |
318 | other = rb_entry(other_node, struct extent_state, rb_node); | |
319 | if (other->end == state->start - 1 && | |
320 | other->state == state->state) { | |
321 | state->start = other->start; | |
322 | other->in_tree = 0; | |
323 | rb_erase(&other->rb_node, &tree->state); | |
324 | free_extent_state(other); | |
325 | } | |
326 | } | |
327 | other_node = rb_next(&state->rb_node); | |
328 | if (other_node) { | |
329 | other = rb_entry(other_node, struct extent_state, rb_node); | |
330 | if (other->start == state->end + 1 && | |
331 | other->state == state->state) { | |
332 | other->start = state->start; | |
333 | state->in_tree = 0; | |
334 | rb_erase(&state->rb_node, &tree->state); | |
335 | free_extent_state(state); | |
336 | } | |
337 | } | |
338 | return 0; | |
339 | } | |
340 | ||
341 | /* | |
342 | * insert an extent_state struct into the tree. 'bits' are set on the | |
343 | * struct before it is inserted. | |
344 | * | |
345 | * This may return -EEXIST if the extent is already there, in which case the | |
346 | * state struct is freed. | |
347 | * | |
348 | * The tree lock is not taken internally. This is a utility function and | |
349 | * probably isn't what you want to call (see set/clear_extent_bit). | |
350 | */ | |
351 | static int insert_state(struct extent_map_tree *tree, | |
352 | struct extent_state *state, u64 start, u64 end, | |
353 | int bits) | |
354 | { | |
355 | struct rb_node *node; | |
356 | ||
357 | if (end < start) { | |
358 | printk("end < start %Lu %Lu\n", end, start); | |
359 | WARN_ON(1); | |
360 | } | |
361 | state->state |= bits; | |
362 | state->start = start; | |
363 | state->end = end; | |
364 | if ((end & 4095) == 0) { | |
365 | printk("insert state %Lu %Lu strange end\n", start, end); | |
366 | WARN_ON(1); | |
367 | } | |
368 | node = tree_insert(&tree->state, end, &state->rb_node); | |
369 | if (node) { | |
370 | struct extent_state *found; | |
371 | found = rb_entry(node, struct extent_state, rb_node); | |
b888db2b | 372 | printk("found node %Lu %Lu on insert of %Lu %Lu\n", found->start, found->end, start, end); |
a52d9a80 CM |
373 | free_extent_state(state); |
374 | return -EEXIST; | |
375 | } | |
376 | merge_state(tree, state); | |
377 | return 0; | |
378 | } | |
379 | ||
380 | /* | |
381 | * split a given extent state struct in two, inserting the preallocated | |
382 | * struct 'prealloc' as the newly created second half. 'split' indicates an | |
383 | * offset inside 'orig' where it should be split. | |
384 | * | |
385 | * Before calling, | |
386 | * the tree has 'orig' at [orig->start, orig->end]. After calling, there | |
387 | * are two extent state structs in the tree: | |
388 | * prealloc: [orig->start, split - 1] | |
389 | * orig: [ split, orig->end ] | |
390 | * | |
391 | * The tree locks are not taken by this function. They need to be held | |
392 | * by the caller. | |
393 | */ | |
394 | static int split_state(struct extent_map_tree *tree, struct extent_state *orig, | |
395 | struct extent_state *prealloc, u64 split) | |
396 | { | |
397 | struct rb_node *node; | |
398 | prealloc->start = orig->start; | |
399 | prealloc->end = split - 1; | |
400 | prealloc->state = orig->state; | |
401 | orig->start = split; | |
402 | if ((prealloc->end & 4095) == 0) { | |
403 | printk("insert state %Lu %Lu strange end\n", prealloc->start, | |
404 | prealloc->end); | |
405 | WARN_ON(1); | |
406 | } | |
407 | node = tree_insert(&tree->state, prealloc->end, &prealloc->rb_node); | |
408 | if (node) { | |
409 | struct extent_state *found; | |
410 | found = rb_entry(node, struct extent_state, rb_node); | |
b888db2b | 411 | printk("found node %Lu %Lu on insert of %Lu %Lu\n", found->start, found->end, prealloc->start, prealloc->end); |
a52d9a80 CM |
412 | free_extent_state(prealloc); |
413 | return -EEXIST; | |
414 | } | |
415 | return 0; | |
416 | } | |
417 | ||
418 | /* | |
419 | * utility function to clear some bits in an extent state struct. | |
420 | * it will optionally wake up any one waiting on this state (wake == 1), or | |
421 | * forcibly remove the state from the tree (delete == 1). | |
422 | * | |
423 | * If no bits are set on the state struct after clearing things, the | |
424 | * struct is freed and removed from the tree | |
425 | */ | |
426 | static int clear_state_bit(struct extent_map_tree *tree, | |
427 | struct extent_state *state, int bits, int wake, | |
428 | int delete) | |
429 | { | |
430 | int ret = state->state & bits; | |
431 | state->state &= ~bits; | |
432 | if (wake) | |
433 | wake_up(&state->wq); | |
434 | if (delete || state->state == 0) { | |
435 | if (state->in_tree) { | |
436 | rb_erase(&state->rb_node, &tree->state); | |
437 | state->in_tree = 0; | |
438 | free_extent_state(state); | |
439 | } else { | |
440 | WARN_ON(1); | |
441 | } | |
442 | } else { | |
443 | merge_state(tree, state); | |
444 | } | |
445 | return ret; | |
446 | } | |
447 | ||
448 | /* | |
449 | * clear some bits on a range in the tree. This may require splitting | |
450 | * or inserting elements in the tree, so the gfp mask is used to | |
451 | * indicate which allocations or sleeping are allowed. | |
452 | * | |
453 | * pass 'wake' == 1 to kick any sleepers, and 'delete' == 1 to remove | |
454 | * the given range from the tree regardless of state (ie for truncate). | |
455 | * | |
456 | * the range [start, end] is inclusive. | |
457 | * | |
458 | * This takes the tree lock, and returns < 0 on error, > 0 if any of the | |
459 | * bits were already set, or zero if none of the bits were already set. | |
460 | */ | |
461 | int clear_extent_bit(struct extent_map_tree *tree, u64 start, u64 end, | |
462 | int bits, int wake, int delete, gfp_t mask) | |
463 | { | |
464 | struct extent_state *state; | |
465 | struct extent_state *prealloc = NULL; | |
466 | struct rb_node *node; | |
90f1c19a | 467 | unsigned long flags; |
a52d9a80 CM |
468 | int err; |
469 | int set = 0; | |
470 | ||
471 | again: | |
472 | if (!prealloc && (mask & __GFP_WAIT)) { | |
473 | prealloc = alloc_extent_state(mask); | |
474 | if (!prealloc) | |
475 | return -ENOMEM; | |
476 | } | |
477 | ||
90f1c19a | 478 | write_lock_irqsave(&tree->lock, flags); |
a52d9a80 CM |
479 | /* |
480 | * this search will find the extents that end after | |
481 | * our range starts | |
482 | */ | |
483 | node = tree_search(&tree->state, start); | |
484 | if (!node) | |
485 | goto out; | |
486 | state = rb_entry(node, struct extent_state, rb_node); | |
487 | if (state->start > end) | |
488 | goto out; | |
489 | WARN_ON(state->end < start); | |
490 | ||
491 | /* | |
492 | * | ---- desired range ---- | | |
493 | * | state | or | |
494 | * | ------------- state -------------- | | |
495 | * | |
496 | * We need to split the extent we found, and may flip | |
497 | * bits on second half. | |
498 | * | |
499 | * If the extent we found extends past our range, we | |
500 | * just split and search again. It'll get split again | |
501 | * the next time though. | |
502 | * | |
503 | * If the extent we found is inside our range, we clear | |
504 | * the desired bit on it. | |
505 | */ | |
506 | ||
507 | if (state->start < start) { | |
508 | err = split_state(tree, state, prealloc, start); | |
509 | BUG_ON(err == -EEXIST); | |
510 | prealloc = NULL; | |
511 | if (err) | |
512 | goto out; | |
513 | if (state->end <= end) { | |
514 | start = state->end + 1; | |
515 | set |= clear_state_bit(tree, state, bits, | |
516 | wake, delete); | |
517 | } else { | |
518 | start = state->start; | |
519 | } | |
520 | goto search_again; | |
521 | } | |
522 | /* | |
523 | * | ---- desired range ---- | | |
524 | * | state | | |
525 | * We need to split the extent, and clear the bit | |
526 | * on the first half | |
527 | */ | |
528 | if (state->start <= end && state->end > end) { | |
529 | err = split_state(tree, state, prealloc, end + 1); | |
530 | BUG_ON(err == -EEXIST); | |
531 | ||
532 | if (wake) | |
533 | wake_up(&state->wq); | |
534 | set |= clear_state_bit(tree, prealloc, bits, | |
535 | wake, delete); | |
536 | prealloc = NULL; | |
537 | goto out; | |
538 | } | |
539 | ||
540 | start = state->end + 1; | |
541 | set |= clear_state_bit(tree, state, bits, wake, delete); | |
542 | goto search_again; | |
543 | ||
544 | out: | |
90f1c19a | 545 | write_unlock_irqrestore(&tree->lock, flags); |
a52d9a80 CM |
546 | if (prealloc) |
547 | free_extent_state(prealloc); | |
548 | ||
549 | return set; | |
550 | ||
551 | search_again: | |
552 | if (start >= end) | |
553 | goto out; | |
90f1c19a | 554 | write_unlock_irqrestore(&tree->lock, flags); |
a52d9a80 CM |
555 | if (mask & __GFP_WAIT) |
556 | cond_resched(); | |
557 | goto again; | |
558 | } | |
559 | EXPORT_SYMBOL(clear_extent_bit); | |
560 | ||
561 | static int wait_on_state(struct extent_map_tree *tree, | |
562 | struct extent_state *state) | |
563 | { | |
564 | DEFINE_WAIT(wait); | |
565 | prepare_to_wait(&state->wq, &wait, TASK_UNINTERRUPTIBLE); | |
566 | read_unlock_irq(&tree->lock); | |
567 | schedule(); | |
568 | read_lock_irq(&tree->lock); | |
569 | finish_wait(&state->wq, &wait); | |
570 | return 0; | |
571 | } | |
572 | ||
573 | /* | |
574 | * waits for one or more bits to clear on a range in the state tree. | |
575 | * The range [start, end] is inclusive. | |
576 | * The tree lock is taken by this function | |
577 | */ | |
578 | int wait_extent_bit(struct extent_map_tree *tree, u64 start, u64 end, int bits) | |
579 | { | |
580 | struct extent_state *state; | |
581 | struct rb_node *node; | |
582 | ||
583 | read_lock_irq(&tree->lock); | |
584 | again: | |
585 | while (1) { | |
586 | /* | |
587 | * this search will find all the extents that end after | |
588 | * our range starts | |
589 | */ | |
590 | node = tree_search(&tree->state, start); | |
591 | if (!node) | |
592 | break; | |
593 | ||
594 | state = rb_entry(node, struct extent_state, rb_node); | |
595 | ||
596 | if (state->start > end) | |
597 | goto out; | |
598 | ||
599 | if (state->state & bits) { | |
600 | start = state->start; | |
601 | atomic_inc(&state->refs); | |
602 | wait_on_state(tree, state); | |
603 | free_extent_state(state); | |
604 | goto again; | |
605 | } | |
606 | start = state->end + 1; | |
607 | ||
608 | if (start > end) | |
609 | break; | |
610 | ||
611 | if (need_resched()) { | |
612 | read_unlock_irq(&tree->lock); | |
613 | cond_resched(); | |
614 | read_lock_irq(&tree->lock); | |
615 | } | |
616 | } | |
617 | out: | |
618 | read_unlock_irq(&tree->lock); | |
619 | return 0; | |
620 | } | |
621 | EXPORT_SYMBOL(wait_extent_bit); | |
622 | ||
623 | /* | |
624 | * set some bits on a range in the tree. This may require allocations | |
625 | * or sleeping, so the gfp mask is used to indicate what is allowed. | |
626 | * | |
627 | * If 'exclusive' == 1, this will fail with -EEXIST if some part of the | |
628 | * range already has the desired bits set. The start of the existing | |
629 | * range is returned in failed_start in this case. | |
630 | * | |
631 | * [start, end] is inclusive | |
632 | * This takes the tree lock. | |
633 | */ | |
634 | int set_extent_bit(struct extent_map_tree *tree, u64 start, u64 end, int bits, | |
635 | int exclusive, u64 *failed_start, gfp_t mask) | |
636 | { | |
637 | struct extent_state *state; | |
638 | struct extent_state *prealloc = NULL; | |
639 | struct rb_node *node; | |
90f1c19a | 640 | unsigned long flags; |
a52d9a80 CM |
641 | int err = 0; |
642 | int set; | |
643 | u64 last_start; | |
644 | u64 last_end; | |
645 | again: | |
646 | if (!prealloc && (mask & __GFP_WAIT)) { | |
647 | prealloc = alloc_extent_state(mask); | |
648 | if (!prealloc) | |
649 | return -ENOMEM; | |
650 | } | |
651 | ||
90f1c19a | 652 | write_lock_irqsave(&tree->lock, flags); |
a52d9a80 CM |
653 | /* |
654 | * this search will find all the extents that end after | |
655 | * our range starts. | |
656 | */ | |
657 | node = tree_search(&tree->state, start); | |
658 | if (!node) { | |
659 | err = insert_state(tree, prealloc, start, end, bits); | |
660 | prealloc = NULL; | |
661 | BUG_ON(err == -EEXIST); | |
662 | goto out; | |
663 | } | |
664 | ||
665 | state = rb_entry(node, struct extent_state, rb_node); | |
666 | last_start = state->start; | |
667 | last_end = state->end; | |
668 | ||
669 | /* | |
670 | * | ---- desired range ---- | | |
671 | * | state | | |
672 | * | |
673 | * Just lock what we found and keep going | |
674 | */ | |
675 | if (state->start == start && state->end <= end) { | |
676 | set = state->state & bits; | |
677 | if (set && exclusive) { | |
678 | *failed_start = state->start; | |
679 | err = -EEXIST; | |
680 | goto out; | |
681 | } | |
682 | state->state |= bits; | |
683 | start = state->end + 1; | |
684 | merge_state(tree, state); | |
685 | goto search_again; | |
686 | } | |
687 | ||
688 | /* | |
689 | * | ---- desired range ---- | | |
690 | * | state | | |
691 | * or | |
692 | * | ------------- state -------------- | | |
693 | * | |
694 | * We need to split the extent we found, and may flip bits on | |
695 | * second half. | |
696 | * | |
697 | * If the extent we found extends past our | |
698 | * range, we just split and search again. It'll get split | |
699 | * again the next time though. | |
700 | * | |
701 | * If the extent we found is inside our range, we set the | |
702 | * desired bit on it. | |
703 | */ | |
704 | if (state->start < start) { | |
705 | set = state->state & bits; | |
706 | if (exclusive && set) { | |
707 | *failed_start = start; | |
708 | err = -EEXIST; | |
709 | goto out; | |
710 | } | |
711 | err = split_state(tree, state, prealloc, start); | |
712 | BUG_ON(err == -EEXIST); | |
713 | prealloc = NULL; | |
714 | if (err) | |
715 | goto out; | |
716 | if (state->end <= end) { | |
717 | state->state |= bits; | |
718 | start = state->end + 1; | |
719 | merge_state(tree, state); | |
720 | } else { | |
721 | start = state->start; | |
722 | } | |
723 | goto search_again; | |
724 | } | |
a52d9a80 CM |
725 | /* |
726 | * | ---- desired range ---- | | |
727 | * | state | or | state | | |
728 | * | |
729 | * There's a hole, we need to insert something in it and | |
730 | * ignore the extent we found. | |
731 | */ | |
732 | if (state->start > start) { | |
733 | u64 this_end; | |
734 | if (end < last_start) | |
735 | this_end = end; | |
736 | else | |
737 | this_end = last_start -1; | |
738 | err = insert_state(tree, prealloc, start, this_end, | |
739 | bits); | |
740 | prealloc = NULL; | |
741 | BUG_ON(err == -EEXIST); | |
742 | if (err) | |
743 | goto out; | |
744 | start = this_end + 1; | |
745 | goto search_again; | |
746 | } | |
a8c450b2 CM |
747 | /* |
748 | * | ---- desired range ---- | | |
749 | * | state | | |
750 | * We need to split the extent, and set the bit | |
751 | * on the first half | |
752 | */ | |
753 | if (state->start <= end && state->end > end) { | |
754 | set = state->state & bits; | |
755 | if (exclusive && set) { | |
756 | *failed_start = start; | |
757 | err = -EEXIST; | |
758 | goto out; | |
759 | } | |
760 | err = split_state(tree, state, prealloc, end + 1); | |
761 | BUG_ON(err == -EEXIST); | |
762 | ||
763 | prealloc->state |= bits; | |
764 | merge_state(tree, prealloc); | |
765 | prealloc = NULL; | |
766 | goto out; | |
767 | } | |
768 | ||
a52d9a80 CM |
769 | goto search_again; |
770 | ||
771 | out: | |
90f1c19a | 772 | write_unlock_irqrestore(&tree->lock, flags); |
a52d9a80 CM |
773 | if (prealloc) |
774 | free_extent_state(prealloc); | |
775 | ||
776 | return err; | |
777 | ||
778 | search_again: | |
779 | if (start > end) | |
780 | goto out; | |
90f1c19a | 781 | write_unlock_irqrestore(&tree->lock, flags); |
a52d9a80 CM |
782 | if (mask & __GFP_WAIT) |
783 | cond_resched(); | |
784 | goto again; | |
785 | } | |
786 | EXPORT_SYMBOL(set_extent_bit); | |
787 | ||
788 | /* wrappers around set/clear extent bit */ | |
789 | int set_extent_dirty(struct extent_map_tree *tree, u64 start, u64 end, | |
790 | gfp_t mask) | |
791 | { | |
792 | return set_extent_bit(tree, start, end, EXTENT_DIRTY, 0, NULL, | |
793 | mask); | |
794 | } | |
795 | EXPORT_SYMBOL(set_extent_dirty); | |
796 | ||
b888db2b CM |
797 | int set_extent_delalloc(struct extent_map_tree *tree, u64 start, u64 end, |
798 | gfp_t mask) | |
799 | { | |
800 | return set_extent_bit(tree, start, end, | |
801 | EXTENT_DELALLOC | EXTENT_DIRTY, 0, NULL, | |
802 | mask); | |
803 | } | |
804 | EXPORT_SYMBOL(set_extent_delalloc); | |
805 | ||
a52d9a80 CM |
806 | int clear_extent_dirty(struct extent_map_tree *tree, u64 start, u64 end, |
807 | gfp_t mask) | |
808 | { | |
b888db2b CM |
809 | return clear_extent_bit(tree, start, end, |
810 | EXTENT_DIRTY | EXTENT_DELALLOC, 0, 0, mask); | |
a52d9a80 CM |
811 | } |
812 | EXPORT_SYMBOL(clear_extent_dirty); | |
813 | ||
814 | int set_extent_new(struct extent_map_tree *tree, u64 start, u64 end, | |
815 | gfp_t mask) | |
816 | { | |
817 | return set_extent_bit(tree, start, end, EXTENT_NEW, 0, NULL, | |
818 | mask); | |
819 | } | |
820 | EXPORT_SYMBOL(set_extent_new); | |
821 | ||
822 | int clear_extent_new(struct extent_map_tree *tree, u64 start, u64 end, | |
823 | gfp_t mask) | |
824 | { | |
825 | return clear_extent_bit(tree, start, end, EXTENT_NEW, 0, 0, mask); | |
826 | } | |
827 | EXPORT_SYMBOL(clear_extent_new); | |
828 | ||
829 | int set_extent_uptodate(struct extent_map_tree *tree, u64 start, u64 end, | |
830 | gfp_t mask) | |
831 | { | |
832 | return set_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, NULL, | |
833 | mask); | |
834 | } | |
835 | EXPORT_SYMBOL(set_extent_uptodate); | |
836 | ||
837 | int clear_extent_uptodate(struct extent_map_tree *tree, u64 start, u64 end, | |
838 | gfp_t mask) | |
839 | { | |
840 | return clear_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, 0, mask); | |
841 | } | |
842 | EXPORT_SYMBOL(clear_extent_uptodate); | |
843 | ||
844 | int set_extent_writeback(struct extent_map_tree *tree, u64 start, u64 end, | |
845 | gfp_t mask) | |
846 | { | |
847 | return set_extent_bit(tree, start, end, EXTENT_WRITEBACK, | |
848 | 0, NULL, mask); | |
849 | } | |
850 | EXPORT_SYMBOL(set_extent_writeback); | |
851 | ||
852 | int clear_extent_writeback(struct extent_map_tree *tree, u64 start, u64 end, | |
853 | gfp_t mask) | |
854 | { | |
855 | return clear_extent_bit(tree, start, end, EXTENT_WRITEBACK, 1, 0, mask); | |
856 | } | |
857 | EXPORT_SYMBOL(clear_extent_writeback); | |
858 | ||
859 | int wait_on_extent_writeback(struct extent_map_tree *tree, u64 start, u64 end) | |
860 | { | |
861 | return wait_extent_bit(tree, start, end, EXTENT_WRITEBACK); | |
862 | } | |
863 | EXPORT_SYMBOL(wait_on_extent_writeback); | |
864 | ||
865 | /* | |
866 | * locks a range in ascending order, waiting for any locked regions | |
867 | * it hits on the way. [start,end] are inclusive, and this will sleep. | |
868 | */ | |
869 | int lock_extent(struct extent_map_tree *tree, u64 start, u64 end, gfp_t mask) | |
870 | { | |
871 | int err; | |
872 | u64 failed_start; | |
873 | while (1) { | |
874 | err = set_extent_bit(tree, start, end, EXTENT_LOCKED, 1, | |
875 | &failed_start, mask); | |
876 | if (err == -EEXIST && (mask & __GFP_WAIT)) { | |
877 | wait_extent_bit(tree, failed_start, end, EXTENT_LOCKED); | |
878 | start = failed_start; | |
879 | } else { | |
880 | break; | |
881 | } | |
882 | WARN_ON(start > end); | |
883 | } | |
884 | return err; | |
885 | } | |
886 | EXPORT_SYMBOL(lock_extent); | |
887 | ||
888 | int unlock_extent(struct extent_map_tree *tree, u64 start, u64 end, | |
889 | gfp_t mask) | |
890 | { | |
891 | return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, mask); | |
892 | } | |
893 | EXPORT_SYMBOL(unlock_extent); | |
894 | ||
895 | /* | |
896 | * helper function to set pages and extents in the tree dirty | |
897 | */ | |
898 | int set_range_dirty(struct extent_map_tree *tree, u64 start, u64 end) | |
899 | { | |
900 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
901 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
902 | struct page *page; | |
903 | ||
904 | while (index <= end_index) { | |
905 | page = find_get_page(tree->mapping, index); | |
906 | BUG_ON(!page); | |
907 | __set_page_dirty_nobuffers(page); | |
908 | page_cache_release(page); | |
909 | index++; | |
910 | } | |
911 | set_extent_dirty(tree, start, end, GFP_NOFS); | |
912 | return 0; | |
913 | } | |
914 | EXPORT_SYMBOL(set_range_dirty); | |
915 | ||
916 | /* | |
917 | * helper function to set both pages and extents in the tree writeback | |
918 | */ | |
919 | int set_range_writeback(struct extent_map_tree *tree, u64 start, u64 end) | |
920 | { | |
921 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
922 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
923 | struct page *page; | |
924 | ||
925 | while (index <= end_index) { | |
926 | page = find_get_page(tree->mapping, index); | |
927 | BUG_ON(!page); | |
928 | set_page_writeback(page); | |
929 | page_cache_release(page); | |
930 | index++; | |
931 | } | |
932 | set_extent_writeback(tree, start, end, GFP_NOFS); | |
933 | return 0; | |
934 | } | |
935 | EXPORT_SYMBOL(set_range_writeback); | |
936 | ||
5f39d397 CM |
937 | int find_first_extent_bit(struct extent_map_tree *tree, u64 start, |
938 | u64 *start_ret, u64 *end_ret, int bits) | |
939 | { | |
940 | struct rb_node *node; | |
941 | struct extent_state *state; | |
942 | int ret = 1; | |
943 | ||
944 | write_lock_irq(&tree->lock); | |
945 | /* | |
946 | * this search will find all the extents that end after | |
947 | * our range starts. | |
948 | */ | |
949 | node = tree_search(&tree->state, start); | |
950 | if (!node || IS_ERR(node)) { | |
951 | goto out; | |
952 | } | |
953 | ||
954 | while(1) { | |
955 | state = rb_entry(node, struct extent_state, rb_node); | |
956 | if (state->state & bits) { | |
957 | *start_ret = state->start; | |
958 | *end_ret = state->end; | |
959 | ret = 0; | |
960 | } | |
961 | node = rb_next(node); | |
962 | if (!node) | |
963 | break; | |
964 | } | |
965 | out: | |
966 | write_unlock_irq(&tree->lock); | |
967 | return ret; | |
968 | } | |
969 | EXPORT_SYMBOL(find_first_extent_bit); | |
970 | ||
b888db2b CM |
971 | u64 find_lock_delalloc_range(struct extent_map_tree *tree, |
972 | u64 start, u64 lock_start, u64 *end, u64 max_bytes) | |
973 | { | |
974 | struct rb_node *node; | |
975 | struct extent_state *state; | |
976 | u64 cur_start = start; | |
977 | u64 found = 0; | |
978 | u64 total_bytes = 0; | |
979 | ||
980 | write_lock_irq(&tree->lock); | |
981 | /* | |
982 | * this search will find all the extents that end after | |
983 | * our range starts. | |
984 | */ | |
985 | search_again: | |
986 | node = tree_search(&tree->state, cur_start); | |
987 | if (!node || IS_ERR(node)) { | |
988 | goto out; | |
989 | } | |
990 | ||
991 | while(1) { | |
992 | state = rb_entry(node, struct extent_state, rb_node); | |
993 | if (state->start != cur_start) { | |
994 | goto out; | |
995 | } | |
996 | if (!(state->state & EXTENT_DELALLOC)) { | |
997 | goto out; | |
998 | } | |
999 | if (state->start >= lock_start) { | |
1000 | if (state->state & EXTENT_LOCKED) { | |
1001 | DEFINE_WAIT(wait); | |
1002 | atomic_inc(&state->refs); | |
1003 | write_unlock_irq(&tree->lock); | |
1004 | schedule(); | |
1005 | write_lock_irq(&tree->lock); | |
1006 | finish_wait(&state->wq, &wait); | |
1007 | free_extent_state(state); | |
1008 | goto search_again; | |
1009 | } | |
1010 | state->state |= EXTENT_LOCKED; | |
1011 | } | |
1012 | found++; | |
1013 | *end = state->end; | |
1014 | cur_start = state->end + 1; | |
1015 | node = rb_next(node); | |
1016 | if (!node) | |
1017 | break; | |
1018 | total_bytes = state->end - state->start + 1; | |
1019 | if (total_bytes >= max_bytes) | |
1020 | break; | |
1021 | } | |
1022 | out: | |
1023 | write_unlock_irq(&tree->lock); | |
1024 | return found; | |
1025 | } | |
1026 | ||
a52d9a80 CM |
1027 | /* |
1028 | * helper function to lock both pages and extents in the tree. | |
1029 | * pages must be locked first. | |
1030 | */ | |
1031 | int lock_range(struct extent_map_tree *tree, u64 start, u64 end) | |
1032 | { | |
1033 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1034 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
1035 | struct page *page; | |
1036 | int err; | |
1037 | ||
1038 | while (index <= end_index) { | |
1039 | page = grab_cache_page(tree->mapping, index); | |
1040 | if (!page) { | |
1041 | err = -ENOMEM; | |
1042 | goto failed; | |
1043 | } | |
1044 | if (IS_ERR(page)) { | |
1045 | err = PTR_ERR(page); | |
1046 | goto failed; | |
1047 | } | |
1048 | index++; | |
1049 | } | |
1050 | lock_extent(tree, start, end, GFP_NOFS); | |
1051 | return 0; | |
1052 | ||
1053 | failed: | |
1054 | /* | |
1055 | * we failed above in getting the page at 'index', so we undo here | |
1056 | * up to but not including the page at 'index' | |
1057 | */ | |
1058 | end_index = index; | |
1059 | index = start >> PAGE_CACHE_SHIFT; | |
1060 | while (index < end_index) { | |
1061 | page = find_get_page(tree->mapping, index); | |
1062 | unlock_page(page); | |
1063 | page_cache_release(page); | |
1064 | index++; | |
1065 | } | |
1066 | return err; | |
1067 | } | |
1068 | EXPORT_SYMBOL(lock_range); | |
1069 | ||
1070 | /* | |
1071 | * helper function to unlock both pages and extents in the tree. | |
1072 | */ | |
1073 | int unlock_range(struct extent_map_tree *tree, u64 start, u64 end) | |
1074 | { | |
1075 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1076 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
1077 | struct page *page; | |
1078 | ||
1079 | while (index <= end_index) { | |
1080 | page = find_get_page(tree->mapping, index); | |
1081 | unlock_page(page); | |
1082 | page_cache_release(page); | |
1083 | index++; | |
1084 | } | |
1085 | unlock_extent(tree, start, end, GFP_NOFS); | |
1086 | return 0; | |
1087 | } | |
1088 | EXPORT_SYMBOL(unlock_range); | |
1089 | ||
07157aac CM |
1090 | int set_state_private(struct extent_map_tree *tree, u64 start, u64 private) |
1091 | { | |
1092 | struct rb_node *node; | |
1093 | struct extent_state *state; | |
1094 | int ret = 0; | |
1095 | ||
1096 | write_lock_irq(&tree->lock); | |
1097 | /* | |
1098 | * this search will find all the extents that end after | |
1099 | * our range starts. | |
1100 | */ | |
1101 | node = tree_search(&tree->state, start); | |
1102 | if (!node || IS_ERR(node)) { | |
1103 | ret = -ENOENT; | |
1104 | goto out; | |
1105 | } | |
1106 | state = rb_entry(node, struct extent_state, rb_node); | |
1107 | if (state->start != start) { | |
1108 | ret = -ENOENT; | |
1109 | goto out; | |
1110 | } | |
1111 | state->private = private; | |
1112 | out: | |
1113 | write_unlock_irq(&tree->lock); | |
1114 | return ret; | |
1115 | ||
1116 | } | |
1117 | ||
1118 | int get_state_private(struct extent_map_tree *tree, u64 start, u64 *private) | |
1119 | { | |
1120 | struct rb_node *node; | |
1121 | struct extent_state *state; | |
1122 | int ret = 0; | |
1123 | ||
1124 | read_lock_irq(&tree->lock); | |
1125 | /* | |
1126 | * this search will find all the extents that end after | |
1127 | * our range starts. | |
1128 | */ | |
1129 | node = tree_search(&tree->state, start); | |
1130 | if (!node || IS_ERR(node)) { | |
1131 | ret = -ENOENT; | |
1132 | goto out; | |
1133 | } | |
1134 | state = rb_entry(node, struct extent_state, rb_node); | |
1135 | if (state->start != start) { | |
1136 | ret = -ENOENT; | |
1137 | goto out; | |
1138 | } | |
1139 | *private = state->private; | |
1140 | out: | |
1141 | read_unlock_irq(&tree->lock); | |
1142 | return ret; | |
1143 | } | |
1144 | ||
a52d9a80 CM |
1145 | /* |
1146 | * searches a range in the state tree for a given mask. | |
1147 | * If 'filled' == 1, this returns 1 only if ever extent in the tree | |
1148 | * has the bits set. Otherwise, 1 is returned if any bit in the | |
1149 | * range is found set. | |
1150 | */ | |
1151 | static int test_range_bit(struct extent_map_tree *tree, u64 start, u64 end, | |
1152 | int bits, int filled) | |
1153 | { | |
1154 | struct extent_state *state = NULL; | |
1155 | struct rb_node *node; | |
1156 | int bitset = 0; | |
1157 | ||
1158 | read_lock_irq(&tree->lock); | |
1159 | node = tree_search(&tree->state, start); | |
1160 | while (node && start <= end) { | |
1161 | state = rb_entry(node, struct extent_state, rb_node); | |
1162 | if (state->start > end) | |
1163 | break; | |
1164 | ||
1165 | if (filled && state->start > start) { | |
1166 | bitset = 0; | |
1167 | break; | |
1168 | } | |
1169 | if (state->state & bits) { | |
1170 | bitset = 1; | |
1171 | if (!filled) | |
1172 | break; | |
1173 | } else if (filled) { | |
1174 | bitset = 0; | |
1175 | break; | |
1176 | } | |
1177 | start = state->end + 1; | |
1178 | if (start > end) | |
1179 | break; | |
1180 | node = rb_next(node); | |
1181 | } | |
1182 | read_unlock_irq(&tree->lock); | |
1183 | return bitset; | |
1184 | } | |
1185 | ||
1186 | /* | |
1187 | * helper function to set a given page up to date if all the | |
1188 | * extents in the tree for that page are up to date | |
1189 | */ | |
1190 | static int check_page_uptodate(struct extent_map_tree *tree, | |
1191 | struct page *page) | |
1192 | { | |
1193 | u64 start = page->index << PAGE_CACHE_SHIFT; | |
1194 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
1195 | if (test_range_bit(tree, start, end, EXTENT_UPTODATE, 1)) | |
1196 | SetPageUptodate(page); | |
1197 | return 0; | |
1198 | } | |
1199 | ||
1200 | /* | |
1201 | * helper function to unlock a page if all the extents in the tree | |
1202 | * for that page are unlocked | |
1203 | */ | |
1204 | static int check_page_locked(struct extent_map_tree *tree, | |
1205 | struct page *page) | |
1206 | { | |
1207 | u64 start = page->index << PAGE_CACHE_SHIFT; | |
1208 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
1209 | if (!test_range_bit(tree, start, end, EXTENT_LOCKED, 0)) | |
1210 | unlock_page(page); | |
1211 | return 0; | |
1212 | } | |
1213 | ||
1214 | /* | |
1215 | * helper function to end page writeback if all the extents | |
1216 | * in the tree for that page are done with writeback | |
1217 | */ | |
1218 | static int check_page_writeback(struct extent_map_tree *tree, | |
1219 | struct page *page) | |
1220 | { | |
1221 | u64 start = page->index << PAGE_CACHE_SHIFT; | |
1222 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
1223 | if (!test_range_bit(tree, start, end, EXTENT_WRITEBACK, 0)) | |
1224 | end_page_writeback(page); | |
1225 | return 0; | |
1226 | } | |
1227 | ||
1228 | /* lots and lots of room for performance fixes in the end_bio funcs */ | |
1229 | ||
1230 | /* | |
1231 | * after a writepage IO is done, we need to: | |
1232 | * clear the uptodate bits on error | |
1233 | * clear the writeback bits in the extent tree for this IO | |
1234 | * end_page_writeback if the page has no more pending IO | |
1235 | * | |
1236 | * Scheduling is not allowed, so the extent state tree is expected | |
1237 | * to have one and only one object corresponding to this IO. | |
1238 | */ | |
1239 | static int end_bio_extent_writepage(struct bio *bio, | |
1240 | unsigned int bytes_done, int err) | |
1241 | { | |
1242 | const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); | |
1243 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; | |
1244 | struct extent_map_tree *tree = bio->bi_private; | |
1245 | u64 start; | |
1246 | u64 end; | |
1247 | int whole_page; | |
1248 | ||
1249 | if (bio->bi_size) | |
1250 | return 1; | |
1251 | ||
1252 | do { | |
1253 | struct page *page = bvec->bv_page; | |
1254 | start = (page->index << PAGE_CACHE_SHIFT) + bvec->bv_offset; | |
1255 | end = start + bvec->bv_len - 1; | |
1256 | ||
1257 | if (bvec->bv_offset == 0 && bvec->bv_len == PAGE_CACHE_SIZE) | |
1258 | whole_page = 1; | |
1259 | else | |
1260 | whole_page = 0; | |
1261 | ||
1262 | if (--bvec >= bio->bi_io_vec) | |
1263 | prefetchw(&bvec->bv_page->flags); | |
1264 | ||
1265 | if (!uptodate) { | |
1266 | clear_extent_uptodate(tree, start, end, GFP_ATOMIC); | |
1267 | ClearPageUptodate(page); | |
1268 | SetPageError(page); | |
1269 | } | |
1270 | clear_extent_writeback(tree, start, end, GFP_ATOMIC); | |
1271 | ||
1272 | if (whole_page) | |
1273 | end_page_writeback(page); | |
1274 | else | |
1275 | check_page_writeback(tree, page); | |
0e2752a7 CH |
1276 | if (tree->ops && tree->ops->writepage_end_io_hook) |
1277 | tree->ops->writepage_end_io_hook(page, start, end); | |
a52d9a80 CM |
1278 | } while (bvec >= bio->bi_io_vec); |
1279 | ||
1280 | bio_put(bio); | |
1281 | return 0; | |
1282 | } | |
1283 | ||
1284 | /* | |
1285 | * after a readpage IO is done, we need to: | |
1286 | * clear the uptodate bits on error | |
1287 | * set the uptodate bits if things worked | |
1288 | * set the page up to date if all extents in the tree are uptodate | |
1289 | * clear the lock bit in the extent tree | |
1290 | * unlock the page if there are no other extents locked for it | |
1291 | * | |
1292 | * Scheduling is not allowed, so the extent state tree is expected | |
1293 | * to have one and only one object corresponding to this IO. | |
1294 | */ | |
1295 | static int end_bio_extent_readpage(struct bio *bio, | |
1296 | unsigned int bytes_done, int err) | |
1297 | { | |
07157aac | 1298 | int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); |
a52d9a80 CM |
1299 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; |
1300 | struct extent_map_tree *tree = bio->bi_private; | |
1301 | u64 start; | |
1302 | u64 end; | |
1303 | int whole_page; | |
07157aac | 1304 | int ret; |
a52d9a80 CM |
1305 | |
1306 | if (bio->bi_size) | |
1307 | return 1; | |
1308 | ||
1309 | do { | |
1310 | struct page *page = bvec->bv_page; | |
1311 | start = (page->index << PAGE_CACHE_SHIFT) + bvec->bv_offset; | |
1312 | end = start + bvec->bv_len - 1; | |
1313 | ||
1314 | if (bvec->bv_offset == 0 && bvec->bv_len == PAGE_CACHE_SIZE) | |
1315 | whole_page = 1; | |
1316 | else | |
1317 | whole_page = 0; | |
1318 | ||
1319 | if (--bvec >= bio->bi_io_vec) | |
1320 | prefetchw(&bvec->bv_page->flags); | |
1321 | ||
07157aac CM |
1322 | if (uptodate && tree->ops && tree->ops->readpage_end_io_hook) { |
1323 | ret = tree->ops->readpage_end_io_hook(page, start, end); | |
1324 | if (ret) | |
1325 | uptodate = 0; | |
1326 | } | |
a52d9a80 CM |
1327 | if (uptodate) { |
1328 | set_extent_uptodate(tree, start, end, GFP_ATOMIC); | |
1329 | if (whole_page) | |
1330 | SetPageUptodate(page); | |
1331 | else | |
1332 | check_page_uptodate(tree, page); | |
1333 | } else { | |
1334 | ClearPageUptodate(page); | |
1335 | SetPageError(page); | |
1336 | } | |
1337 | ||
1338 | unlock_extent(tree, start, end, GFP_ATOMIC); | |
1339 | ||
1340 | if (whole_page) | |
1341 | unlock_page(page); | |
1342 | else | |
1343 | check_page_locked(tree, page); | |
1344 | } while (bvec >= bio->bi_io_vec); | |
1345 | ||
1346 | bio_put(bio); | |
1347 | return 0; | |
1348 | } | |
1349 | ||
1350 | /* | |
1351 | * IO done from prepare_write is pretty simple, we just unlock | |
1352 | * the structs in the extent tree when done, and set the uptodate bits | |
1353 | * as appropriate. | |
1354 | */ | |
1355 | static int end_bio_extent_preparewrite(struct bio *bio, | |
1356 | unsigned int bytes_done, int err) | |
1357 | { | |
1358 | const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); | |
1359 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; | |
1360 | struct extent_map_tree *tree = bio->bi_private; | |
1361 | u64 start; | |
1362 | u64 end; | |
1363 | ||
1364 | if (bio->bi_size) | |
1365 | return 1; | |
1366 | ||
1367 | do { | |
1368 | struct page *page = bvec->bv_page; | |
1369 | start = (page->index << PAGE_CACHE_SHIFT) + bvec->bv_offset; | |
1370 | end = start + bvec->bv_len - 1; | |
1371 | ||
1372 | if (--bvec >= bio->bi_io_vec) | |
1373 | prefetchw(&bvec->bv_page->flags); | |
1374 | ||
1375 | if (uptodate) { | |
1376 | set_extent_uptodate(tree, start, end, GFP_ATOMIC); | |
1377 | } else { | |
1378 | ClearPageUptodate(page); | |
1379 | SetPageError(page); | |
1380 | } | |
1381 | ||
1382 | unlock_extent(tree, start, end, GFP_ATOMIC); | |
1383 | ||
1384 | } while (bvec >= bio->bi_io_vec); | |
1385 | ||
1386 | bio_put(bio); | |
1387 | return 0; | |
1388 | } | |
1389 | ||
1390 | static int submit_extent_page(int rw, struct extent_map_tree *tree, | |
1391 | struct page *page, sector_t sector, | |
1392 | size_t size, unsigned long offset, | |
1393 | struct block_device *bdev, | |
1394 | bio_end_io_t end_io_func) | |
1395 | { | |
1396 | struct bio *bio; | |
1397 | int ret = 0; | |
1398 | ||
1399 | bio = bio_alloc(GFP_NOIO, 1); | |
1400 | ||
1401 | bio->bi_sector = sector; | |
1402 | bio->bi_bdev = bdev; | |
1403 | bio->bi_io_vec[0].bv_page = page; | |
1404 | bio->bi_io_vec[0].bv_len = size; | |
1405 | bio->bi_io_vec[0].bv_offset = offset; | |
1406 | ||
1407 | bio->bi_vcnt = 1; | |
1408 | bio->bi_idx = 0; | |
1409 | bio->bi_size = size; | |
1410 | ||
1411 | bio->bi_end_io = end_io_func; | |
1412 | bio->bi_private = tree; | |
1413 | ||
1414 | bio_get(bio); | |
1415 | submit_bio(rw, bio); | |
1416 | ||
1417 | if (bio_flagged(bio, BIO_EOPNOTSUPP)) | |
1418 | ret = -EOPNOTSUPP; | |
1419 | ||
1420 | bio_put(bio); | |
1421 | return ret; | |
1422 | } | |
1423 | ||
b3cfa35a CH |
1424 | void set_page_extent_mapped(struct page *page) |
1425 | { | |
1426 | if (!PagePrivate(page)) { | |
1427 | SetPagePrivate(page); | |
1428 | WARN_ON(!page->mapping->a_ops->invalidatepage); | |
1429 | set_page_private(page, 1); | |
1430 | page_cache_get(page); | |
1431 | } | |
1432 | } | |
1433 | ||
a52d9a80 CM |
1434 | /* |
1435 | * basic readpage implementation. Locked extent state structs are inserted | |
1436 | * into the tree that are removed when the IO is done (by the end_io | |
1437 | * handlers) | |
1438 | */ | |
1439 | int extent_read_full_page(struct extent_map_tree *tree, struct page *page, | |
1440 | get_extent_t *get_extent) | |
1441 | { | |
1442 | struct inode *inode = page->mapping->host; | |
1443 | u64 start = page->index << PAGE_CACHE_SHIFT; | |
1444 | u64 page_end = start + PAGE_CACHE_SIZE - 1; | |
1445 | u64 end; | |
1446 | u64 cur = start; | |
1447 | u64 extent_offset; | |
1448 | u64 last_byte = i_size_read(inode); | |
1449 | u64 block_start; | |
1450 | u64 cur_end; | |
1451 | sector_t sector; | |
1452 | struct extent_map *em; | |
1453 | struct block_device *bdev; | |
1454 | int ret; | |
1455 | int nr = 0; | |
1456 | size_t page_offset = 0; | |
1457 | size_t iosize; | |
1458 | size_t blocksize = inode->i_sb->s_blocksize; | |
1459 | ||
b3cfa35a | 1460 | set_page_extent_mapped(page); |
a52d9a80 CM |
1461 | |
1462 | end = page_end; | |
1463 | lock_extent(tree, start, end, GFP_NOFS); | |
1464 | ||
1465 | while (cur <= end) { | |
1466 | if (cur >= last_byte) { | |
1467 | iosize = PAGE_CACHE_SIZE - page_offset; | |
1468 | zero_user_page(page, page_offset, iosize, KM_USER0); | |
1469 | set_extent_uptodate(tree, cur, cur + iosize - 1, | |
1470 | GFP_NOFS); | |
1471 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); | |
1472 | break; | |
1473 | } | |
1474 | em = get_extent(inode, page, page_offset, cur, end, 0); | |
1475 | if (IS_ERR(em) || !em) { | |
1476 | SetPageError(page); | |
1477 | unlock_extent(tree, cur, end, GFP_NOFS); | |
1478 | break; | |
1479 | } | |
1480 | ||
1481 | extent_offset = cur - em->start; | |
1482 | BUG_ON(em->end < cur); | |
1483 | BUG_ON(end < cur); | |
1484 | ||
1485 | iosize = min(em->end - cur, end - cur) + 1; | |
1486 | cur_end = min(em->end, end); | |
1487 | iosize = (iosize + blocksize - 1) & ~((u64)blocksize - 1); | |
1488 | sector = (em->block_start + extent_offset) >> 9; | |
1489 | bdev = em->bdev; | |
1490 | block_start = em->block_start; | |
1491 | free_extent_map(em); | |
1492 | em = NULL; | |
1493 | ||
1494 | /* we've found a hole, just zero and go on */ | |
5f39d397 | 1495 | if (block_start == EXTENT_MAP_HOLE) { |
a52d9a80 CM |
1496 | zero_user_page(page, page_offset, iosize, KM_USER0); |
1497 | set_extent_uptodate(tree, cur, cur + iosize - 1, | |
1498 | GFP_NOFS); | |
1499 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); | |
1500 | cur = cur + iosize; | |
1501 | page_offset += iosize; | |
1502 | continue; | |
1503 | } | |
1504 | /* the get_extent function already copied into the page */ | |
1505 | if (test_range_bit(tree, cur, cur_end, EXTENT_UPTODATE, 1)) { | |
1506 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); | |
1507 | cur = cur + iosize; | |
1508 | page_offset += iosize; | |
1509 | continue; | |
1510 | } | |
1511 | ||
07157aac CM |
1512 | ret = 0; |
1513 | if (tree->ops && tree->ops->readpage_io_hook) { | |
1514 | ret = tree->ops->readpage_io_hook(page, cur, | |
1515 | cur + iosize - 1); | |
1516 | } | |
1517 | if (!ret) { | |
1518 | ret = submit_extent_page(READ, tree, page, | |
1519 | sector, iosize, page_offset, | |
1520 | bdev, end_bio_extent_readpage); | |
1521 | } | |
a52d9a80 CM |
1522 | if (ret) |
1523 | SetPageError(page); | |
1524 | cur = cur + iosize; | |
1525 | page_offset += iosize; | |
1526 | nr++; | |
1527 | } | |
1528 | if (!nr) { | |
1529 | if (!PageError(page)) | |
1530 | SetPageUptodate(page); | |
1531 | unlock_page(page); | |
1532 | } | |
1533 | return 0; | |
1534 | } | |
1535 | EXPORT_SYMBOL(extent_read_full_page); | |
1536 | ||
1537 | /* | |
1538 | * the writepage semantics are similar to regular writepage. extent | |
1539 | * records are inserted to lock ranges in the tree, and as dirty areas | |
1540 | * are found, they are marked writeback. Then the lock bits are removed | |
1541 | * and the end_io handler clears the writeback ranges | |
1542 | */ | |
1543 | int extent_write_full_page(struct extent_map_tree *tree, struct page *page, | |
1544 | get_extent_t *get_extent, | |
1545 | struct writeback_control *wbc) | |
1546 | { | |
1547 | struct inode *inode = page->mapping->host; | |
1548 | u64 start = page->index << PAGE_CACHE_SHIFT; | |
1549 | u64 page_end = start + PAGE_CACHE_SIZE - 1; | |
1550 | u64 end; | |
1551 | u64 cur = start; | |
1552 | u64 extent_offset; | |
1553 | u64 last_byte = i_size_read(inode); | |
1554 | u64 block_start; | |
1555 | sector_t sector; | |
1556 | struct extent_map *em; | |
1557 | struct block_device *bdev; | |
1558 | int ret; | |
1559 | int nr = 0; | |
1560 | size_t page_offset = 0; | |
1561 | size_t iosize; | |
1562 | size_t blocksize; | |
1563 | loff_t i_size = i_size_read(inode); | |
1564 | unsigned long end_index = i_size >> PAGE_CACHE_SHIFT; | |
b888db2b CM |
1565 | u64 nr_delalloc; |
1566 | u64 delalloc_end; | |
a52d9a80 | 1567 | |
b888db2b | 1568 | WARN_ON(!PageLocked(page)); |
a52d9a80 CM |
1569 | if (page->index > end_index) { |
1570 | clear_extent_dirty(tree, start, page_end, GFP_NOFS); | |
1571 | unlock_page(page); | |
1572 | return 0; | |
1573 | } | |
1574 | ||
1575 | if (page->index == end_index) { | |
1576 | size_t offset = i_size & (PAGE_CACHE_SIZE - 1); | |
1577 | zero_user_page(page, offset, | |
1578 | PAGE_CACHE_SIZE - offset, KM_USER0); | |
1579 | } | |
1580 | ||
b3cfa35a | 1581 | set_page_extent_mapped(page); |
a52d9a80 | 1582 | |
a52d9a80 | 1583 | lock_extent(tree, start, page_end, GFP_NOFS); |
b888db2b CM |
1584 | nr_delalloc = find_lock_delalloc_range(tree, start, page_end + 1, |
1585 | &delalloc_end, | |
1586 | 128 * 1024 * 1024); | |
1587 | if (nr_delalloc) { | |
07157aac | 1588 | tree->ops->fill_delalloc(inode, start, delalloc_end); |
b888db2b CM |
1589 | if (delalloc_end >= page_end + 1) { |
1590 | clear_extent_bit(tree, page_end + 1, delalloc_end, | |
1591 | EXTENT_LOCKED | EXTENT_DELALLOC, | |
1592 | 1, 0, GFP_NOFS); | |
1593 | } | |
1594 | clear_extent_bit(tree, start, page_end, EXTENT_DELALLOC, | |
1595 | 0, 0, GFP_NOFS); | |
1596 | if (test_range_bit(tree, start, page_end, EXTENT_DELALLOC, 0)) { | |
1597 | printk("found delalloc bits after clear extent_bit\n"); | |
1598 | } | |
1599 | } else if (test_range_bit(tree, start, page_end, EXTENT_DELALLOC, 0)) { | |
1600 | printk("found delalloc bits after find_delalloc_range returns 0\n"); | |
1601 | } | |
1602 | ||
1603 | end = page_end; | |
1604 | if (test_range_bit(tree, start, page_end, EXTENT_DELALLOC, 0)) { | |
1605 | printk("found delalloc bits after lock_extent\n"); | |
1606 | } | |
a52d9a80 CM |
1607 | |
1608 | if (last_byte <= start) { | |
1609 | clear_extent_dirty(tree, start, page_end, GFP_NOFS); | |
1610 | goto done; | |
1611 | } | |
1612 | ||
1613 | set_extent_uptodate(tree, start, page_end, GFP_NOFS); | |
1614 | blocksize = inode->i_sb->s_blocksize; | |
1615 | ||
1616 | while (cur <= end) { | |
1617 | if (cur >= last_byte) { | |
1618 | clear_extent_dirty(tree, cur, page_end, GFP_NOFS); | |
1619 | break; | |
1620 | } | |
b888db2b | 1621 | em = get_extent(inode, page, page_offset, cur, end, 0); |
a52d9a80 CM |
1622 | if (IS_ERR(em) || !em) { |
1623 | SetPageError(page); | |
1624 | break; | |
1625 | } | |
1626 | ||
1627 | extent_offset = cur - em->start; | |
1628 | BUG_ON(em->end < cur); | |
1629 | BUG_ON(end < cur); | |
1630 | iosize = min(em->end - cur, end - cur) + 1; | |
1631 | iosize = (iosize + blocksize - 1) & ~((u64)blocksize - 1); | |
1632 | sector = (em->block_start + extent_offset) >> 9; | |
1633 | bdev = em->bdev; | |
1634 | block_start = em->block_start; | |
1635 | free_extent_map(em); | |
1636 | em = NULL; | |
1637 | ||
5f39d397 CM |
1638 | if (block_start == EXTENT_MAP_HOLE || |
1639 | block_start == EXTENT_MAP_INLINE) { | |
a52d9a80 CM |
1640 | clear_extent_dirty(tree, cur, |
1641 | cur + iosize - 1, GFP_NOFS); | |
1642 | cur = cur + iosize; | |
1643 | page_offset += iosize; | |
1644 | continue; | |
1645 | } | |
1646 | ||
1647 | /* leave this out until we have a page_mkwrite call */ | |
1648 | if (0 && !test_range_bit(tree, cur, cur + iosize - 1, | |
1649 | EXTENT_DIRTY, 0)) { | |
1650 | cur = cur + iosize; | |
1651 | page_offset += iosize; | |
1652 | continue; | |
1653 | } | |
1654 | clear_extent_dirty(tree, cur, cur + iosize - 1, GFP_NOFS); | |
b06355f0 CH |
1655 | if (tree->ops && tree->ops->writepage_io_hook) { |
1656 | ret = tree->ops->writepage_io_hook(page, cur, | |
1657 | cur + iosize - 1); | |
1658 | } else { | |
1659 | ret = 0; | |
1660 | } | |
a52d9a80 CM |
1661 | if (ret) |
1662 | SetPageError(page); | |
07157aac CM |
1663 | else { |
1664 | set_range_writeback(tree, cur, cur + iosize - 1); | |
1665 | ret = submit_extent_page(WRITE, tree, page, sector, | |
1666 | iosize, page_offset, bdev, | |
1667 | end_bio_extent_writepage); | |
1668 | if (ret) | |
1669 | SetPageError(page); | |
1670 | } | |
a52d9a80 CM |
1671 | cur = cur + iosize; |
1672 | page_offset += iosize; | |
1673 | nr++; | |
1674 | } | |
1675 | done: | |
a52d9a80 CM |
1676 | unlock_extent(tree, start, page_end, GFP_NOFS); |
1677 | unlock_page(page); | |
1678 | return 0; | |
1679 | } | |
1680 | EXPORT_SYMBOL(extent_write_full_page); | |
1681 | ||
1682 | /* | |
1683 | * basic invalidatepage code, this waits on any locked or writeback | |
1684 | * ranges corresponding to the page, and then deletes any extent state | |
1685 | * records from the tree | |
1686 | */ | |
1687 | int extent_invalidatepage(struct extent_map_tree *tree, | |
1688 | struct page *page, unsigned long offset) | |
1689 | { | |
1690 | u64 start = (page->index << PAGE_CACHE_SHIFT); | |
1691 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
1692 | size_t blocksize = page->mapping->host->i_sb->s_blocksize; | |
1693 | ||
1694 | start += (offset + blocksize -1) & ~(blocksize - 1); | |
1695 | if (start > end) | |
1696 | return 0; | |
1697 | ||
1698 | lock_extent(tree, start, end, GFP_NOFS); | |
1699 | wait_on_extent_writeback(tree, start, end); | |
2bf5a725 CM |
1700 | clear_extent_bit(tree, start, end, |
1701 | EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC, | |
a52d9a80 CM |
1702 | 1, 1, GFP_NOFS); |
1703 | return 0; | |
1704 | } | |
1705 | EXPORT_SYMBOL(extent_invalidatepage); | |
1706 | ||
1707 | /* | |
1708 | * simple commit_write call, set_range_dirty is used to mark both | |
1709 | * the pages and the extent records as dirty | |
1710 | */ | |
1711 | int extent_commit_write(struct extent_map_tree *tree, | |
1712 | struct inode *inode, struct page *page, | |
1713 | unsigned from, unsigned to) | |
1714 | { | |
1715 | loff_t pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to; | |
1716 | ||
b3cfa35a | 1717 | set_page_extent_mapped(page); |
a52d9a80 CM |
1718 | set_page_dirty(page); |
1719 | ||
1720 | if (pos > inode->i_size) { | |
1721 | i_size_write(inode, pos); | |
1722 | mark_inode_dirty(inode); | |
1723 | } | |
1724 | return 0; | |
1725 | } | |
1726 | EXPORT_SYMBOL(extent_commit_write); | |
1727 | ||
1728 | int extent_prepare_write(struct extent_map_tree *tree, | |
1729 | struct inode *inode, struct page *page, | |
1730 | unsigned from, unsigned to, get_extent_t *get_extent) | |
1731 | { | |
1732 | u64 page_start = page->index << PAGE_CACHE_SHIFT; | |
1733 | u64 page_end = page_start + PAGE_CACHE_SIZE - 1; | |
1734 | u64 block_start; | |
1735 | u64 orig_block_start; | |
1736 | u64 block_end; | |
1737 | u64 cur_end; | |
1738 | struct extent_map *em; | |
1739 | unsigned blocksize = 1 << inode->i_blkbits; | |
1740 | size_t page_offset = 0; | |
1741 | size_t block_off_start; | |
1742 | size_t block_off_end; | |
1743 | int err = 0; | |
1744 | int iocount = 0; | |
1745 | int ret = 0; | |
1746 | int isnew; | |
1747 | ||
b3cfa35a CH |
1748 | set_page_extent_mapped(page); |
1749 | ||
a52d9a80 CM |
1750 | block_start = (page_start + from) & ~((u64)blocksize - 1); |
1751 | block_end = (page_start + to - 1) | (blocksize - 1); | |
1752 | orig_block_start = block_start; | |
1753 | ||
1754 | lock_extent(tree, page_start, page_end, GFP_NOFS); | |
1755 | while(block_start <= block_end) { | |
1756 | em = get_extent(inode, page, page_offset, block_start, | |
1757 | block_end, 1); | |
1758 | if (IS_ERR(em) || !em) { | |
1759 | goto err; | |
1760 | } | |
1761 | cur_end = min(block_end, em->end); | |
1762 | block_off_start = block_start & (PAGE_CACHE_SIZE - 1); | |
1763 | block_off_end = block_off_start + blocksize; | |
1764 | isnew = clear_extent_new(tree, block_start, cur_end, GFP_NOFS); | |
1765 | ||
1766 | if (!PageUptodate(page) && isnew && | |
1767 | (block_off_end > to || block_off_start < from)) { | |
1768 | void *kaddr; | |
1769 | ||
1770 | kaddr = kmap_atomic(page, KM_USER0); | |
1771 | if (block_off_end > to) | |
1772 | memset(kaddr + to, 0, block_off_end - to); | |
1773 | if (block_off_start < from) | |
1774 | memset(kaddr + block_off_start, 0, | |
1775 | from - block_off_start); | |
1776 | flush_dcache_page(page); | |
1777 | kunmap_atomic(kaddr, KM_USER0); | |
1778 | } | |
1779 | if (!isnew && !PageUptodate(page) && | |
1780 | (block_off_end > to || block_off_start < from) && | |
1781 | !test_range_bit(tree, block_start, cur_end, | |
1782 | EXTENT_UPTODATE, 1)) { | |
1783 | u64 sector; | |
1784 | u64 extent_offset = block_start - em->start; | |
1785 | size_t iosize; | |
1786 | sector = (em->block_start + extent_offset) >> 9; | |
1787 | iosize = (cur_end - block_start + blocksize - 1) & | |
1788 | ~((u64)blocksize - 1); | |
1789 | /* | |
1790 | * we've already got the extent locked, but we | |
1791 | * need to split the state such that our end_bio | |
1792 | * handler can clear the lock. | |
1793 | */ | |
1794 | set_extent_bit(tree, block_start, | |
1795 | block_start + iosize - 1, | |
1796 | EXTENT_LOCKED, 0, NULL, GFP_NOFS); | |
1797 | ret = submit_extent_page(READ, tree, page, | |
1798 | sector, iosize, page_offset, em->bdev, | |
1799 | end_bio_extent_preparewrite); | |
1800 | iocount++; | |
1801 | block_start = block_start + iosize; | |
1802 | } else { | |
1803 | set_extent_uptodate(tree, block_start, cur_end, | |
1804 | GFP_NOFS); | |
1805 | unlock_extent(tree, block_start, cur_end, GFP_NOFS); | |
1806 | block_start = cur_end + 1; | |
1807 | } | |
1808 | page_offset = block_start & (PAGE_CACHE_SIZE - 1); | |
1809 | free_extent_map(em); | |
1810 | } | |
1811 | if (iocount) { | |
1812 | wait_extent_bit(tree, orig_block_start, | |
1813 | block_end, EXTENT_LOCKED); | |
1814 | } | |
1815 | check_page_uptodate(tree, page); | |
1816 | err: | |
1817 | /* FIXME, zero out newly allocated blocks on error */ | |
1818 | return err; | |
1819 | } | |
1820 | EXPORT_SYMBOL(extent_prepare_write); | |
1821 | ||
1822 | /* | |
1823 | * a helper for releasepage. As long as there are no locked extents | |
1824 | * in the range corresponding to the page, both state records and extent | |
1825 | * map records are removed | |
1826 | */ | |
1827 | int try_release_extent_mapping(struct extent_map_tree *tree, struct page *page) | |
1828 | { | |
1829 | struct extent_map *em; | |
1830 | u64 start = page->index << PAGE_CACHE_SHIFT; | |
1831 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
1832 | u64 orig_start = start; | |
b888db2b | 1833 | int ret = 1; |
a52d9a80 CM |
1834 | |
1835 | while (start <= end) { | |
1836 | em = lookup_extent_mapping(tree, start, end); | |
1837 | if (!em || IS_ERR(em)) | |
1838 | break; | |
b888db2b CM |
1839 | if (!test_range_bit(tree, em->start, em->end, |
1840 | EXTENT_LOCKED, 0)) { | |
1841 | remove_extent_mapping(tree, em); | |
1842 | /* once for the rb tree */ | |
a52d9a80 | 1843 | free_extent_map(em); |
a52d9a80 | 1844 | } |
a52d9a80 | 1845 | start = em->end + 1; |
a52d9a80 CM |
1846 | /* once for us */ |
1847 | free_extent_map(em); | |
1848 | } | |
b888db2b CM |
1849 | if (test_range_bit(tree, orig_start, end, EXTENT_LOCKED, 0)) |
1850 | ret = 0; | |
1851 | else | |
1852 | clear_extent_bit(tree, orig_start, end, EXTENT_UPTODATE, | |
1853 | 1, 1, GFP_NOFS); | |
1854 | return ret; | |
a52d9a80 CM |
1855 | } |
1856 | EXPORT_SYMBOL(try_release_extent_mapping); | |
1857 | ||
d396c6f5 CH |
1858 | sector_t extent_bmap(struct address_space *mapping, sector_t iblock, |
1859 | get_extent_t *get_extent) | |
1860 | { | |
1861 | struct inode *inode = mapping->host; | |
1862 | u64 start = iblock << inode->i_blkbits; | |
1863 | u64 end = start + (1 << inode->i_blkbits) - 1; | |
1864 | struct extent_map *em; | |
1865 | ||
1866 | em = get_extent(inode, NULL, 0, start, end, 0); | |
1867 | if (!em || IS_ERR(em)) | |
1868 | return 0; | |
1869 | ||
d396c6f5 | 1870 | if (em->block_start == EXTENT_MAP_INLINE || |
5f39d397 CM |
1871 | em->block_start == EXTENT_MAP_HOLE) |
1872 | return 0; | |
d396c6f5 CH |
1873 | |
1874 | return (em->block_start + start - em->start) >> inode->i_blkbits; | |
1875 | } | |
5f39d397 | 1876 | |
6d36dcd4 CM |
1877 | static struct extent_buffer *__alloc_extent_buffer(gfp_t mask) |
1878 | { | |
1879 | struct extent_buffer *eb = NULL; | |
1880 | spin_lock(&extent_buffers_lock); | |
1881 | if (!list_empty(&extent_buffers)) { | |
1882 | eb = list_entry(extent_buffers.next, struct extent_buffer, | |
1883 | list); | |
1884 | list_del(&eb->list); | |
1885 | WARN_ON(nr_extent_buffers == 0); | |
1886 | nr_extent_buffers--; | |
1887 | } | |
1888 | spin_unlock(&extent_buffers_lock); | |
1889 | if (eb) { | |
1890 | memset(eb, 0, sizeof(*eb)); | |
1891 | return eb; | |
1892 | } | |
1893 | return kmem_cache_zalloc(extent_buffer_cache, mask); | |
1894 | } | |
1895 | ||
1896 | static void __free_extent_buffer(struct extent_buffer *eb) | |
1897 | { | |
1898 | if (nr_extent_buffers >= MAX_EXTENT_BUFFER_CACHE) { | |
1899 | kmem_cache_free(extent_buffer_cache, eb); | |
1900 | } else { | |
1901 | spin_lock(&extent_buffers_lock); | |
1902 | list_add(&eb->list, &extent_buffers); | |
1903 | nr_extent_buffers++; | |
1904 | spin_unlock(&extent_buffers_lock); | |
1905 | } | |
1906 | } | |
1907 | ||
1908 | static inline struct page *extent_buffer_page(struct extent_buffer *eb, int i) | |
1909 | { | |
1910 | struct page *p; | |
1911 | if (i == 0) | |
1912 | return eb->first_page; | |
1913 | i += eb->start >> PAGE_CACHE_SHIFT; | |
1914 | p = find_get_page(eb->first_page->mapping, i); | |
1915 | page_cache_release(p); | |
1916 | return p; | |
1917 | } | |
1918 | ||
5f39d397 CM |
1919 | struct extent_buffer *alloc_extent_buffer(struct extent_map_tree *tree, |
1920 | u64 start, unsigned long len, | |
1921 | gfp_t mask) | |
1922 | { | |
1923 | unsigned long num_pages = ((start + len - 1) >> PAGE_CACHE_SHIFT) - | |
1924 | (start >> PAGE_CACHE_SHIFT) + 1; | |
1925 | unsigned long i; | |
1926 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1927 | struct extent_buffer *eb; | |
1928 | struct page *p; | |
1929 | struct address_space *mapping = tree->mapping; | |
1930 | int uptodate = 0; | |
1931 | ||
6d36dcd4 | 1932 | eb = __alloc_extent_buffer(mask); |
5f39d397 CM |
1933 | if (!eb || IS_ERR(eb)) |
1934 | return NULL; | |
1935 | ||
1936 | eb->start = start; | |
1937 | eb->len = len; | |
1938 | atomic_set(&eb->refs, 1); | |
1939 | ||
1940 | for (i = 0; i < num_pages; i++, index++) { | |
1941 | p = find_or_create_page(mapping, index, mask | __GFP_HIGHMEM); | |
6d36dcd4 CM |
1942 | if (!p) { |
1943 | /* make sure the free only frees the pages we've | |
1944 | * grabbed a reference on | |
1945 | */ | |
1946 | eb->len = i << PAGE_CACHE_SHIFT; | |
1947 | eb->start &= ~((u64)PAGE_CACHE_SIZE - 1); | |
5f39d397 | 1948 | goto fail; |
6d36dcd4 CM |
1949 | } |
1950 | if (i == 0) | |
1951 | eb->first_page = p; | |
5f39d397 CM |
1952 | if (!PageUptodate(p)) |
1953 | uptodate = 0; | |
1954 | unlock_page(p); | |
1955 | } | |
1956 | if (uptodate) | |
1957 | eb->flags |= EXTENT_UPTODATE; | |
1958 | return eb; | |
1959 | fail: | |
1960 | free_extent_buffer(eb); | |
1961 | return NULL; | |
1962 | } | |
1963 | EXPORT_SYMBOL(alloc_extent_buffer); | |
1964 | ||
1965 | struct extent_buffer *find_extent_buffer(struct extent_map_tree *tree, | |
1966 | u64 start, unsigned long len, | |
1967 | gfp_t mask) | |
1968 | { | |
1969 | unsigned long num_pages = ((start + len - 1) >> PAGE_CACHE_SHIFT) - | |
1970 | (start >> PAGE_CACHE_SHIFT) + 1; | |
1971 | unsigned long i; | |
1972 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1973 | struct extent_buffer *eb; | |
1974 | struct page *p; | |
1975 | struct address_space *mapping = tree->mapping; | |
1976 | ||
6d36dcd4 | 1977 | eb = __alloc_extent_buffer(mask); |
5f39d397 CM |
1978 | if (!eb || IS_ERR(eb)) |
1979 | return NULL; | |
1980 | ||
1981 | eb->start = start; | |
1982 | eb->len = len; | |
1983 | atomic_set(&eb->refs, 1); | |
1984 | ||
1985 | for (i = 0; i < num_pages; i++, index++) { | |
1986 | p = find_get_page(mapping, index); | |
6d36dcd4 CM |
1987 | if (!p) { |
1988 | /* make sure the free only frees the pages we've | |
1989 | * grabbed a reference on | |
1990 | */ | |
1991 | eb->len = i << PAGE_CACHE_SHIFT; | |
1992 | eb->start &= ~((u64)PAGE_CACHE_SIZE - 1); | |
5f39d397 | 1993 | goto fail; |
6d36dcd4 CM |
1994 | } |
1995 | if (i == 0) | |
1996 | eb->first_page = p; | |
5f39d397 CM |
1997 | } |
1998 | return eb; | |
1999 | fail: | |
2000 | free_extent_buffer(eb); | |
2001 | return NULL; | |
2002 | } | |
2003 | EXPORT_SYMBOL(find_extent_buffer); | |
2004 | ||
2005 | void free_extent_buffer(struct extent_buffer *eb) | |
2006 | { | |
2007 | unsigned long i; | |
2008 | unsigned long num_pages; | |
2009 | ||
2010 | if (!eb) | |
2011 | return; | |
2012 | ||
2013 | if (!atomic_dec_and_test(&eb->refs)) | |
2014 | return; | |
2015 | ||
2016 | num_pages = ((eb->start + eb->len - 1) >> PAGE_CACHE_SHIFT) - | |
2017 | (eb->start >> PAGE_CACHE_SHIFT) + 1; | |
2018 | ||
6d36dcd4 CM |
2019 | if (eb->first_page) |
2020 | page_cache_release(eb->first_page); | |
2021 | for (i = 1; i < num_pages; i++) { | |
2022 | page_cache_release(extent_buffer_page(eb, i)); | |
5f39d397 | 2023 | } |
6d36dcd4 | 2024 | __free_extent_buffer(eb); |
5f39d397 CM |
2025 | } |
2026 | EXPORT_SYMBOL(free_extent_buffer); | |
2027 | ||
2028 | int clear_extent_buffer_dirty(struct extent_map_tree *tree, | |
2029 | struct extent_buffer *eb) | |
2030 | { | |
2031 | int set; | |
2032 | unsigned long i; | |
2033 | unsigned long num_pages; | |
2034 | struct page *page; | |
2035 | ||
2036 | u64 start = eb->start; | |
2037 | u64 end = start + eb->len - 1; | |
2038 | ||
2039 | set = clear_extent_dirty(tree, start, end, GFP_NOFS); | |
2040 | num_pages = ((eb->start + eb->len - 1) >> PAGE_CACHE_SHIFT) - | |
2041 | (eb->start >> PAGE_CACHE_SHIFT) + 1; | |
2042 | ||
2043 | for (i = 0; i < num_pages; i++) { | |
6d36dcd4 | 2044 | page = extent_buffer_page(eb, i); |
5f39d397 CM |
2045 | lock_page(page); |
2046 | /* | |
2047 | * if we're on the last page or the first page and the | |
2048 | * block isn't aligned on a page boundary, do extra checks | |
2049 | * to make sure we don't clean page that is partially dirty | |
2050 | */ | |
2051 | if ((i == 0 && (eb->start & (PAGE_CACHE_SIZE - 1))) || | |
2052 | ((i == num_pages - 1) && | |
2053 | ((eb->start + eb->len - 1) & (PAGE_CACHE_SIZE - 1)))) { | |
2054 | start = page->index << PAGE_CACHE_SHIFT; | |
2055 | end = start + PAGE_CACHE_SIZE - 1; | |
2056 | if (test_range_bit(tree, start, end, | |
2057 | EXTENT_DIRTY, 0)) { | |
2058 | unlock_page(page); | |
2059 | continue; | |
2060 | } | |
2061 | } | |
2062 | clear_page_dirty_for_io(page); | |
2063 | unlock_page(page); | |
2064 | } | |
2065 | return 0; | |
2066 | } | |
2067 | EXPORT_SYMBOL(clear_extent_buffer_dirty); | |
2068 | ||
2069 | int wait_on_extent_buffer_writeback(struct extent_map_tree *tree, | |
2070 | struct extent_buffer *eb) | |
2071 | { | |
2072 | return wait_on_extent_writeback(tree, eb->start, | |
2073 | eb->start + eb->len - 1); | |
2074 | } | |
2075 | EXPORT_SYMBOL(wait_on_extent_buffer_writeback); | |
2076 | ||
2077 | int set_extent_buffer_dirty(struct extent_map_tree *tree, | |
2078 | struct extent_buffer *eb) | |
2079 | { | |
2080 | return set_range_dirty(tree, eb->start, eb->start + eb->len - 1); | |
2081 | } | |
2082 | EXPORT_SYMBOL(set_extent_buffer_dirty); | |
2083 | ||
2084 | int set_extent_buffer_uptodate(struct extent_map_tree *tree, | |
2085 | struct extent_buffer *eb) | |
2086 | { | |
2087 | unsigned long i; | |
2088 | struct page *page; | |
2089 | unsigned long num_pages; | |
2090 | ||
2091 | num_pages = ((eb->start + eb->len - 1) >> PAGE_CACHE_SHIFT) - | |
2092 | (eb->start >> PAGE_CACHE_SHIFT) + 1; | |
2093 | ||
2094 | set_extent_uptodate(tree, eb->start, eb->start + eb->len - 1, | |
2095 | GFP_NOFS); | |
2096 | for (i = 0; i < num_pages; i++) { | |
6d36dcd4 | 2097 | page = extent_buffer_page(eb, i); |
5f39d397 CM |
2098 | if ((i == 0 && (eb->start & (PAGE_CACHE_SIZE - 1))) || |
2099 | ((i == num_pages - 1) && | |
2100 | ((eb->start + eb->len - 1) & (PAGE_CACHE_SIZE - 1)))) { | |
2101 | check_page_uptodate(tree, page); | |
2102 | continue; | |
2103 | } | |
2104 | SetPageUptodate(page); | |
2105 | } | |
2106 | return 0; | |
2107 | } | |
2108 | EXPORT_SYMBOL(set_extent_buffer_uptodate); | |
2109 | ||
2110 | int extent_buffer_uptodate(struct extent_map_tree *tree, | |
2111 | struct extent_buffer *eb) | |
2112 | { | |
2113 | if (eb->flags & EXTENT_UPTODATE) | |
2114 | return 1; | |
2115 | return test_range_bit(tree, eb->start, eb->start + eb->len - 1, | |
2116 | EXTENT_UPTODATE, 1); | |
2117 | } | |
2118 | EXPORT_SYMBOL(extent_buffer_uptodate); | |
2119 | ||
2120 | int read_extent_buffer_pages(struct extent_map_tree *tree, | |
2121 | struct extent_buffer *eb, int wait) | |
2122 | { | |
2123 | unsigned long i; | |
2124 | struct page *page; | |
2125 | int err; | |
2126 | int ret = 0; | |
2127 | unsigned long num_pages; | |
2128 | ||
2129 | if (eb->flags & EXTENT_UPTODATE) | |
2130 | return 0; | |
2131 | ||
2132 | if (test_range_bit(tree, eb->start, eb->start + eb->len - 1, | |
2133 | EXTENT_UPTODATE, 1)) { | |
2134 | return 0; | |
2135 | } | |
2136 | ||
2137 | num_pages = ((eb->start + eb->len - 1) >> PAGE_CACHE_SHIFT) - | |
2138 | (eb->start >> PAGE_CACHE_SHIFT) + 1; | |
2139 | for (i = 0; i < num_pages; i++) { | |
6d36dcd4 | 2140 | page = extent_buffer_page(eb, i); |
5f39d397 CM |
2141 | if (PageUptodate(page)) { |
2142 | continue; | |
2143 | } | |
2144 | if (!wait) { | |
2145 | if (TestSetPageLocked(page)) { | |
2146 | continue; | |
2147 | } | |
2148 | } else { | |
2149 | lock_page(page); | |
2150 | } | |
2151 | if (!PageUptodate(page)) { | |
2152 | err = page->mapping->a_ops->readpage(NULL, page); | |
2153 | if (err) { | |
2154 | ret = err; | |
2155 | } | |
2156 | } else { | |
2157 | unlock_page(page); | |
2158 | } | |
2159 | } | |
2160 | ||
2161 | if (ret || !wait) { | |
2162 | return ret; | |
2163 | } | |
2164 | ||
2165 | for (i = 0; i < num_pages; i++) { | |
6d36dcd4 | 2166 | page = extent_buffer_page(eb, i); |
5f39d397 CM |
2167 | wait_on_page_locked(page); |
2168 | if (!PageUptodate(page)) { | |
2169 | ret = -EIO; | |
2170 | } | |
2171 | } | |
2172 | eb->flags |= EXTENT_UPTODATE; | |
2173 | return ret; | |
2174 | } | |
2175 | EXPORT_SYMBOL(read_extent_buffer_pages); | |
2176 | ||
2177 | void read_extent_buffer(struct extent_buffer *eb, void *dstv, | |
2178 | unsigned long start, | |
2179 | unsigned long len) | |
2180 | { | |
2181 | size_t cur; | |
2182 | size_t offset; | |
2183 | struct page *page; | |
2184 | char *kaddr; | |
2185 | char *dst = (char *)dstv; | |
2186 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
2187 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
2188 | ||
2189 | WARN_ON(start > eb->len); | |
2190 | WARN_ON(start + len > eb->start + eb->len); | |
2191 | ||
5f39d397 CM |
2192 | offset = start & ((unsigned long)PAGE_CACHE_SIZE - 1); |
2193 | if (i == 0) | |
2194 | offset += start_offset; | |
2195 | ||
2196 | while(len > 0) { | |
6d36dcd4 | 2197 | page = extent_buffer_page(eb, i); |
5f39d397 CM |
2198 | WARN_ON(!PageUptodate(page)); |
2199 | ||
2200 | cur = min(len, (PAGE_CACHE_SIZE - offset)); | |
ae5252bd | 2201 | kaddr = kmap_atomic(page, KM_USER0); |
5f39d397 | 2202 | memcpy(dst, kaddr + offset, cur); |
ae5252bd | 2203 | kunmap_atomic(kaddr, KM_USER0); |
5f39d397 CM |
2204 | |
2205 | dst += cur; | |
2206 | len -= cur; | |
2207 | offset = 0; | |
2208 | i++; | |
5f39d397 CM |
2209 | } |
2210 | } | |
2211 | EXPORT_SYMBOL(read_extent_buffer); | |
2212 | ||
2213 | int map_extent_buffer(struct extent_buffer *eb, unsigned long start, | |
479965d6 | 2214 | unsigned long min_len, |
5f39d397 CM |
2215 | char **token, char **map, |
2216 | unsigned long *map_start, | |
2217 | unsigned long *map_len, int km) | |
2218 | { | |
479965d6 | 2219 | size_t offset = start & (PAGE_CACHE_SIZE - 1); |
5f39d397 CM |
2220 | char *kaddr; |
2221 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
2222 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
479965d6 CM |
2223 | unsigned long end_i = (start_offset + start + min_len) >> |
2224 | PAGE_CACHE_SHIFT; | |
2225 | ||
2226 | if (i != end_i) | |
2227 | return -EINVAL; | |
5f39d397 CM |
2228 | |
2229 | WARN_ON(start > eb->len); | |
2230 | ||
2231 | if (i == 0) { | |
2232 | offset = start_offset; | |
2233 | *map_start = 0; | |
2234 | } else { | |
479965d6 | 2235 | *map_start = (i << PAGE_CACHE_SHIFT) - start_offset; |
5f39d397 CM |
2236 | } |
2237 | ||
ae5252bd | 2238 | kaddr = kmap_atomic(extent_buffer_page(eb, i), km); |
5f39d397 CM |
2239 | *token = kaddr; |
2240 | *map = kaddr + offset; | |
2241 | *map_len = PAGE_CACHE_SIZE - offset; | |
2242 | return 0; | |
2243 | } | |
2244 | EXPORT_SYMBOL(map_extent_buffer); | |
2245 | ||
2246 | void unmap_extent_buffer(struct extent_buffer *eb, char *token, int km) | |
2247 | { | |
ae5252bd | 2248 | kunmap_atomic(token, km); |
5f39d397 CM |
2249 | } |
2250 | EXPORT_SYMBOL(unmap_extent_buffer); | |
2251 | ||
2252 | int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv, | |
2253 | unsigned long start, | |
2254 | unsigned long len) | |
2255 | { | |
2256 | size_t cur; | |
2257 | size_t offset; | |
2258 | struct page *page; | |
2259 | char *kaddr; | |
2260 | char *ptr = (char *)ptrv; | |
2261 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
2262 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
2263 | int ret = 0; | |
2264 | ||
2265 | WARN_ON(start > eb->len); | |
2266 | WARN_ON(start + len > eb->start + eb->len); | |
2267 | ||
5f39d397 CM |
2268 | offset = start & ((unsigned long)PAGE_CACHE_SIZE - 1); |
2269 | if (i == 0) | |
2270 | offset += start_offset; | |
2271 | ||
2272 | while(len > 0) { | |
6d36dcd4 | 2273 | page = extent_buffer_page(eb, i); |
5f39d397 CM |
2274 | WARN_ON(!PageUptodate(page)); |
2275 | ||
2276 | cur = min(len, (PAGE_CACHE_SIZE - offset)); | |
2277 | ||
ae5252bd | 2278 | kaddr = kmap_atomic(page, KM_USER0); |
5f39d397 | 2279 | ret = memcmp(ptr, kaddr + offset, cur); |
ae5252bd | 2280 | kunmap_atomic(kaddr, KM_USER0); |
5f39d397 CM |
2281 | if (ret) |
2282 | break; | |
2283 | ||
2284 | ptr += cur; | |
2285 | len -= cur; | |
2286 | offset = 0; | |
2287 | i++; | |
5f39d397 CM |
2288 | } |
2289 | return ret; | |
2290 | } | |
2291 | EXPORT_SYMBOL(memcmp_extent_buffer); | |
2292 | ||
2293 | void write_extent_buffer(struct extent_buffer *eb, const void *srcv, | |
2294 | unsigned long start, unsigned long len) | |
2295 | { | |
2296 | size_t cur; | |
2297 | size_t offset; | |
2298 | struct page *page; | |
2299 | char *kaddr; | |
2300 | char *src = (char *)srcv; | |
2301 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
2302 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
2303 | ||
2304 | WARN_ON(start > eb->len); | |
2305 | WARN_ON(start + len > eb->start + eb->len); | |
2306 | ||
5f39d397 CM |
2307 | offset = start & ((unsigned long)PAGE_CACHE_SIZE - 1); |
2308 | if (i == 0) | |
2309 | offset += start_offset; | |
2310 | ||
2311 | while(len > 0) { | |
6d36dcd4 | 2312 | page = extent_buffer_page(eb, i); |
5f39d397 CM |
2313 | WARN_ON(!PageUptodate(page)); |
2314 | ||
2315 | cur = min(len, PAGE_CACHE_SIZE - offset); | |
ae5252bd | 2316 | kaddr = kmap_atomic(page, KM_USER0); |
5f39d397 | 2317 | memcpy(kaddr + offset, src, cur); |
ae5252bd | 2318 | kunmap_atomic(kaddr, KM_USER0); |
5f39d397 CM |
2319 | |
2320 | src += cur; | |
2321 | len -= cur; | |
2322 | offset = 0; | |
2323 | i++; | |
5f39d397 CM |
2324 | } |
2325 | } | |
2326 | EXPORT_SYMBOL(write_extent_buffer); | |
2327 | ||
2328 | void memset_extent_buffer(struct extent_buffer *eb, char c, | |
2329 | unsigned long start, unsigned long len) | |
2330 | { | |
2331 | size_t cur; | |
2332 | size_t offset; | |
2333 | struct page *page; | |
2334 | char *kaddr; | |
2335 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
2336 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
2337 | ||
2338 | WARN_ON(start > eb->len); | |
2339 | WARN_ON(start + len > eb->start + eb->len); | |
2340 | ||
5f39d397 CM |
2341 | offset = start & ((unsigned long)PAGE_CACHE_SIZE - 1); |
2342 | if (i == 0) | |
2343 | offset += start_offset; | |
2344 | ||
2345 | while(len > 0) { | |
6d36dcd4 | 2346 | page = extent_buffer_page(eb, i); |
5f39d397 CM |
2347 | WARN_ON(!PageUptodate(page)); |
2348 | ||
2349 | cur = min(len, PAGE_CACHE_SIZE - offset); | |
ae5252bd | 2350 | kaddr = kmap_atomic(page, KM_USER0); |
5f39d397 | 2351 | memset(kaddr + offset, c, cur); |
ae5252bd | 2352 | kunmap_atomic(kaddr, KM_USER0); |
5f39d397 CM |
2353 | |
2354 | len -= cur; | |
2355 | offset = 0; | |
2356 | i++; | |
5f39d397 CM |
2357 | } |
2358 | } | |
2359 | EXPORT_SYMBOL(memset_extent_buffer); | |
2360 | ||
2361 | void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src, | |
2362 | unsigned long dst_offset, unsigned long src_offset, | |
2363 | unsigned long len) | |
2364 | { | |
2365 | u64 dst_len = dst->len; | |
2366 | size_t cur; | |
2367 | size_t offset; | |
2368 | struct page *page; | |
2369 | char *kaddr; | |
2370 | size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); | |
2371 | unsigned long i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT; | |
2372 | ||
2373 | WARN_ON(src->len != dst_len); | |
2374 | ||
2375 | offset = dst_offset & ((unsigned long)PAGE_CACHE_SIZE - 1); | |
2376 | if (i == 0) | |
2377 | offset += start_offset; | |
2378 | ||
2379 | while(len > 0) { | |
6d36dcd4 | 2380 | page = extent_buffer_page(dst, i); |
5f39d397 CM |
2381 | WARN_ON(!PageUptodate(page)); |
2382 | ||
2383 | cur = min(len, (unsigned long)(PAGE_CACHE_SIZE - offset)); | |
2384 | ||
ae5252bd | 2385 | kaddr = kmap_atomic(page, KM_USER1); |
5f39d397 | 2386 | read_extent_buffer(src, kaddr + offset, src_offset, cur); |
ae5252bd | 2387 | kunmap_atomic(kaddr, KM_USER1); |
5f39d397 CM |
2388 | |
2389 | src_offset += cur; | |
2390 | len -= cur; | |
2391 | offset = 0; | |
2392 | i++; | |
2393 | } | |
2394 | } | |
2395 | EXPORT_SYMBOL(copy_extent_buffer); | |
2396 | ||
2397 | static void move_pages(struct page *dst_page, struct page *src_page, | |
2398 | unsigned long dst_off, unsigned long src_off, | |
2399 | unsigned long len) | |
2400 | { | |
ae5252bd | 2401 | char *dst_kaddr = kmap_atomic(dst_page, KM_USER0); |
5f39d397 CM |
2402 | if (dst_page == src_page) { |
2403 | memmove(dst_kaddr + dst_off, dst_kaddr + src_off, len); | |
2404 | } else { | |
ae5252bd | 2405 | char *src_kaddr = kmap_atomic(src_page, KM_USER1); |
5f39d397 CM |
2406 | char *p = dst_kaddr + dst_off + len; |
2407 | char *s = src_kaddr + src_off + len; | |
2408 | ||
2409 | while (len--) | |
2410 | *--p = *--s; | |
2411 | ||
ae5252bd | 2412 | kunmap_atomic(src_kaddr, KM_USER1); |
5f39d397 | 2413 | } |
ae5252bd | 2414 | kunmap_atomic(dst_kaddr, KM_USER0); |
5f39d397 CM |
2415 | } |
2416 | ||
2417 | static void copy_pages(struct page *dst_page, struct page *src_page, | |
2418 | unsigned long dst_off, unsigned long src_off, | |
2419 | unsigned long len) | |
2420 | { | |
ae5252bd | 2421 | char *dst_kaddr = kmap_atomic(dst_page, KM_USER0); |
5f39d397 CM |
2422 | char *src_kaddr; |
2423 | ||
2424 | if (dst_page != src_page) | |
ae5252bd | 2425 | src_kaddr = kmap_atomic(src_page, KM_USER1); |
5f39d397 CM |
2426 | else |
2427 | src_kaddr = dst_kaddr; | |
2428 | ||
2429 | memcpy(dst_kaddr + dst_off, src_kaddr + src_off, len); | |
5f39d397 CM |
2430 | kunmap_atomic(dst_kaddr, KM_USER0); |
2431 | if (dst_page != src_page) | |
2432 | kunmap_atomic(src_kaddr, KM_USER1); | |
5f39d397 CM |
2433 | } |
2434 | ||
2435 | void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, | |
2436 | unsigned long src_offset, unsigned long len) | |
2437 | { | |
2438 | size_t cur; | |
2439 | size_t dst_off_in_page; | |
2440 | size_t src_off_in_page; | |
2441 | size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); | |
2442 | unsigned long dst_i; | |
2443 | unsigned long src_i; | |
2444 | ||
2445 | if (src_offset + len > dst->len) { | |
2446 | printk("memmove bogus src_offset %lu move len %lu len %lu\n", | |
2447 | src_offset, len, dst->len); | |
2448 | BUG_ON(1); | |
2449 | } | |
2450 | if (dst_offset + len > dst->len) { | |
2451 | printk("memmove bogus dst_offset %lu move len %lu len %lu\n", | |
2452 | dst_offset, len, dst->len); | |
2453 | BUG_ON(1); | |
2454 | } | |
2455 | ||
2456 | while(len > 0) { | |
2457 | dst_off_in_page = dst_offset & | |
2458 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
2459 | src_off_in_page = src_offset & | |
2460 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
2461 | ||
2462 | dst_i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT; | |
2463 | src_i = (start_offset + src_offset) >> PAGE_CACHE_SHIFT; | |
2464 | ||
2465 | if (src_i == 0) | |
2466 | src_off_in_page += start_offset; | |
2467 | if (dst_i == 0) | |
2468 | dst_off_in_page += start_offset; | |
2469 | ||
2470 | cur = min(len, (unsigned long)(PAGE_CACHE_SIZE - | |
2471 | src_off_in_page)); | |
2472 | cur = min(cur, (unsigned long)(PAGE_CACHE_SIZE - | |
2473 | dst_off_in_page)); | |
2474 | ||
6d36dcd4 CM |
2475 | copy_pages(extent_buffer_page(dst, dst_i), |
2476 | extent_buffer_page(dst, src_i), | |
5f39d397 CM |
2477 | dst_off_in_page, src_off_in_page, cur); |
2478 | ||
2479 | src_offset += cur; | |
2480 | dst_offset += cur; | |
2481 | len -= cur; | |
2482 | } | |
2483 | } | |
2484 | EXPORT_SYMBOL(memcpy_extent_buffer); | |
2485 | ||
2486 | void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, | |
2487 | unsigned long src_offset, unsigned long len) | |
2488 | { | |
2489 | size_t cur; | |
2490 | size_t dst_off_in_page; | |
2491 | size_t src_off_in_page; | |
2492 | unsigned long dst_end = dst_offset + len - 1; | |
2493 | unsigned long src_end = src_offset + len - 1; | |
2494 | size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); | |
2495 | unsigned long dst_i; | |
2496 | unsigned long src_i; | |
2497 | ||
2498 | if (src_offset + len > dst->len) { | |
2499 | printk("memmove bogus src_offset %lu move len %lu len %lu\n", | |
2500 | src_offset, len, dst->len); | |
2501 | BUG_ON(1); | |
2502 | } | |
2503 | if (dst_offset + len > dst->len) { | |
2504 | printk("memmove bogus dst_offset %lu move len %lu len %lu\n", | |
2505 | dst_offset, len, dst->len); | |
2506 | BUG_ON(1); | |
2507 | } | |
2508 | if (dst_offset < src_offset) { | |
2509 | memcpy_extent_buffer(dst, dst_offset, src_offset, len); | |
2510 | return; | |
2511 | } | |
2512 | while(len > 0) { | |
2513 | dst_i = (start_offset + dst_end) >> PAGE_CACHE_SHIFT; | |
2514 | src_i = (start_offset + src_end) >> PAGE_CACHE_SHIFT; | |
2515 | ||
2516 | dst_off_in_page = dst_end & | |
2517 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
2518 | src_off_in_page = src_end & | |
2519 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
2520 | ||
2521 | if (src_i == 0) | |
2522 | src_off_in_page += start_offset; | |
2523 | if (dst_i == 0) | |
2524 | dst_off_in_page += start_offset; | |
2525 | ||
2526 | cur = min(len, src_off_in_page + 1); | |
2527 | cur = min(cur, dst_off_in_page + 1); | |
ae5252bd | 2528 | |
6d36dcd4 CM |
2529 | move_pages(extent_buffer_page(dst, dst_i), |
2530 | extent_buffer_page(dst, src_i), | |
5f39d397 CM |
2531 | dst_off_in_page - cur + 1, |
2532 | src_off_in_page - cur + 1, cur); | |
2533 | ||
2534 | dst_end -= cur - 1; | |
2535 | src_end -= cur - 1; | |
2536 | len -= cur; | |
2537 | } | |
2538 | } | |
2539 | EXPORT_SYMBOL(memmove_extent_buffer); |