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