Commit | Line | Data |
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d1310b2e CM |
1 | #include <linux/bitops.h> |
2 | #include <linux/slab.h> | |
3 | #include <linux/bio.h> | |
4 | #include <linux/mm.h> | |
5 | #include <linux/gfp.h> | |
6 | #include <linux/pagemap.h> | |
7 | #include <linux/page-flags.h> | |
8 | #include <linux/module.h> | |
9 | #include <linux/spinlock.h> | |
10 | #include <linux/blkdev.h> | |
11 | #include <linux/swap.h> | |
d1310b2e CM |
12 | #include <linux/writeback.h> |
13 | #include <linux/pagevec.h> | |
14 | #include "extent_io.h" | |
15 | #include "extent_map.h" | |
2db04966 | 16 | #include "compat.h" |
902b22f3 DW |
17 | #include "ctree.h" |
18 | #include "btrfs_inode.h" | |
d1310b2e CM |
19 | |
20 | /* temporary define until extent_map moves out of btrfs */ | |
21 | struct kmem_cache *btrfs_cache_create(const char *name, size_t size, | |
22 | unsigned long extra_flags, | |
23 | void (*ctor)(void *, struct kmem_cache *, | |
24 | unsigned long)); | |
25 | ||
26 | static struct kmem_cache *extent_state_cache; | |
27 | static struct kmem_cache *extent_buffer_cache; | |
28 | ||
29 | static LIST_HEAD(buffers); | |
30 | static LIST_HEAD(states); | |
4bef0848 | 31 | |
b47eda86 | 32 | #define LEAK_DEBUG 0 |
3935127c | 33 | #if LEAK_DEBUG |
d397712b | 34 | static DEFINE_SPINLOCK(leak_lock); |
4bef0848 | 35 | #endif |
d1310b2e | 36 | |
d1310b2e CM |
37 | #define BUFFER_LRU_MAX 64 |
38 | ||
39 | struct tree_entry { | |
40 | u64 start; | |
41 | u64 end; | |
d1310b2e CM |
42 | struct rb_node rb_node; |
43 | }; | |
44 | ||
45 | struct extent_page_data { | |
46 | struct bio *bio; | |
47 | struct extent_io_tree *tree; | |
48 | get_extent_t *get_extent; | |
771ed689 CM |
49 | |
50 | /* tells writepage not to lock the state bits for this range | |
51 | * it still does the unlocking | |
52 | */ | |
53 | int extent_locked; | |
d1310b2e CM |
54 | }; |
55 | ||
56 | int __init extent_io_init(void) | |
57 | { | |
58 | extent_state_cache = btrfs_cache_create("extent_state", | |
59 | sizeof(struct extent_state), 0, | |
60 | NULL); | |
61 | if (!extent_state_cache) | |
62 | return -ENOMEM; | |
63 | ||
64 | extent_buffer_cache = btrfs_cache_create("extent_buffers", | |
65 | sizeof(struct extent_buffer), 0, | |
66 | NULL); | |
67 | if (!extent_buffer_cache) | |
68 | goto free_state_cache; | |
69 | return 0; | |
70 | ||
71 | free_state_cache: | |
72 | kmem_cache_destroy(extent_state_cache); | |
73 | return -ENOMEM; | |
74 | } | |
75 | ||
76 | void extent_io_exit(void) | |
77 | { | |
78 | struct extent_state *state; | |
2d2ae547 | 79 | struct extent_buffer *eb; |
d1310b2e CM |
80 | |
81 | while (!list_empty(&states)) { | |
2d2ae547 | 82 | state = list_entry(states.next, struct extent_state, leak_list); |
d397712b CM |
83 | printk(KERN_ERR "btrfs state leak: start %llu end %llu " |
84 | "state %lu in tree %p refs %d\n", | |
85 | (unsigned long long)state->start, | |
86 | (unsigned long long)state->end, | |
87 | state->state, state->tree, atomic_read(&state->refs)); | |
2d2ae547 | 88 | list_del(&state->leak_list); |
d1310b2e CM |
89 | kmem_cache_free(extent_state_cache, state); |
90 | ||
91 | } | |
92 | ||
2d2ae547 CM |
93 | while (!list_empty(&buffers)) { |
94 | eb = list_entry(buffers.next, struct extent_buffer, leak_list); | |
d397712b CM |
95 | printk(KERN_ERR "btrfs buffer leak start %llu len %lu " |
96 | "refs %d\n", (unsigned long long)eb->start, | |
97 | eb->len, atomic_read(&eb->refs)); | |
2d2ae547 CM |
98 | list_del(&eb->leak_list); |
99 | kmem_cache_free(extent_buffer_cache, eb); | |
100 | } | |
d1310b2e CM |
101 | if (extent_state_cache) |
102 | kmem_cache_destroy(extent_state_cache); | |
103 | if (extent_buffer_cache) | |
104 | kmem_cache_destroy(extent_buffer_cache); | |
105 | } | |
106 | ||
107 | void extent_io_tree_init(struct extent_io_tree *tree, | |
108 | struct address_space *mapping, gfp_t mask) | |
109 | { | |
110 | tree->state.rb_node = NULL; | |
6af118ce | 111 | tree->buffer.rb_node = NULL; |
d1310b2e CM |
112 | tree->ops = NULL; |
113 | tree->dirty_bytes = 0; | |
70dec807 | 114 | spin_lock_init(&tree->lock); |
6af118ce | 115 | spin_lock_init(&tree->buffer_lock); |
d1310b2e | 116 | tree->mapping = mapping; |
d1310b2e | 117 | } |
d1310b2e | 118 | |
b2950863 | 119 | static struct extent_state *alloc_extent_state(gfp_t mask) |
d1310b2e CM |
120 | { |
121 | struct extent_state *state; | |
3935127c | 122 | #if LEAK_DEBUG |
2d2ae547 | 123 | unsigned long flags; |
4bef0848 | 124 | #endif |
d1310b2e CM |
125 | |
126 | state = kmem_cache_alloc(extent_state_cache, mask); | |
2b114d1d | 127 | if (!state) |
d1310b2e CM |
128 | return state; |
129 | state->state = 0; | |
d1310b2e | 130 | state->private = 0; |
70dec807 | 131 | state->tree = NULL; |
3935127c | 132 | #if LEAK_DEBUG |
2d2ae547 CM |
133 | spin_lock_irqsave(&leak_lock, flags); |
134 | list_add(&state->leak_list, &states); | |
135 | spin_unlock_irqrestore(&leak_lock, flags); | |
4bef0848 | 136 | #endif |
d1310b2e CM |
137 | atomic_set(&state->refs, 1); |
138 | init_waitqueue_head(&state->wq); | |
139 | return state; | |
140 | } | |
d1310b2e | 141 | |
b2950863 | 142 | static void free_extent_state(struct extent_state *state) |
d1310b2e | 143 | { |
d1310b2e CM |
144 | if (!state) |
145 | return; | |
146 | if (atomic_dec_and_test(&state->refs)) { | |
3935127c | 147 | #if LEAK_DEBUG |
2d2ae547 | 148 | unsigned long flags; |
4bef0848 | 149 | #endif |
70dec807 | 150 | WARN_ON(state->tree); |
3935127c | 151 | #if LEAK_DEBUG |
2d2ae547 CM |
152 | spin_lock_irqsave(&leak_lock, flags); |
153 | list_del(&state->leak_list); | |
154 | spin_unlock_irqrestore(&leak_lock, flags); | |
4bef0848 | 155 | #endif |
d1310b2e CM |
156 | kmem_cache_free(extent_state_cache, state); |
157 | } | |
158 | } | |
d1310b2e CM |
159 | |
160 | static struct rb_node *tree_insert(struct rb_root *root, u64 offset, | |
161 | struct rb_node *node) | |
162 | { | |
d397712b CM |
163 | struct rb_node **p = &root->rb_node; |
164 | struct rb_node *parent = NULL; | |
d1310b2e CM |
165 | struct tree_entry *entry; |
166 | ||
d397712b | 167 | while (*p) { |
d1310b2e CM |
168 | parent = *p; |
169 | entry = rb_entry(parent, struct tree_entry, rb_node); | |
170 | ||
171 | if (offset < entry->start) | |
172 | p = &(*p)->rb_left; | |
173 | else if (offset > entry->end) | |
174 | p = &(*p)->rb_right; | |
175 | else | |
176 | return parent; | |
177 | } | |
178 | ||
179 | entry = rb_entry(node, struct tree_entry, rb_node); | |
d1310b2e CM |
180 | rb_link_node(node, parent, p); |
181 | rb_insert_color(node, root); | |
182 | return NULL; | |
183 | } | |
184 | ||
80ea96b1 | 185 | static struct rb_node *__etree_search(struct extent_io_tree *tree, u64 offset, |
d1310b2e CM |
186 | struct rb_node **prev_ret, |
187 | struct rb_node **next_ret) | |
188 | { | |
80ea96b1 | 189 | struct rb_root *root = &tree->state; |
d397712b | 190 | struct rb_node *n = root->rb_node; |
d1310b2e CM |
191 | struct rb_node *prev = NULL; |
192 | struct rb_node *orig_prev = NULL; | |
193 | struct tree_entry *entry; | |
194 | struct tree_entry *prev_entry = NULL; | |
195 | ||
d397712b | 196 | while (n) { |
d1310b2e CM |
197 | entry = rb_entry(n, struct tree_entry, rb_node); |
198 | prev = n; | |
199 | prev_entry = entry; | |
200 | ||
201 | if (offset < entry->start) | |
202 | n = n->rb_left; | |
203 | else if (offset > entry->end) | |
204 | n = n->rb_right; | |
d397712b | 205 | else |
d1310b2e CM |
206 | return n; |
207 | } | |
208 | ||
209 | if (prev_ret) { | |
210 | orig_prev = prev; | |
d397712b | 211 | while (prev && offset > prev_entry->end) { |
d1310b2e CM |
212 | prev = rb_next(prev); |
213 | prev_entry = rb_entry(prev, struct tree_entry, rb_node); | |
214 | } | |
215 | *prev_ret = prev; | |
216 | prev = orig_prev; | |
217 | } | |
218 | ||
219 | if (next_ret) { | |
220 | prev_entry = rb_entry(prev, struct tree_entry, rb_node); | |
d397712b | 221 | while (prev && offset < prev_entry->start) { |
d1310b2e CM |
222 | prev = rb_prev(prev); |
223 | prev_entry = rb_entry(prev, struct tree_entry, rb_node); | |
224 | } | |
225 | *next_ret = prev; | |
226 | } | |
227 | return NULL; | |
228 | } | |
229 | ||
80ea96b1 CM |
230 | static inline struct rb_node *tree_search(struct extent_io_tree *tree, |
231 | u64 offset) | |
d1310b2e | 232 | { |
70dec807 | 233 | struct rb_node *prev = NULL; |
d1310b2e | 234 | struct rb_node *ret; |
70dec807 | 235 | |
80ea96b1 | 236 | ret = __etree_search(tree, offset, &prev, NULL); |
d397712b | 237 | if (!ret) |
d1310b2e CM |
238 | return prev; |
239 | return ret; | |
240 | } | |
241 | ||
6af118ce CM |
242 | static struct extent_buffer *buffer_tree_insert(struct extent_io_tree *tree, |
243 | u64 offset, struct rb_node *node) | |
244 | { | |
245 | struct rb_root *root = &tree->buffer; | |
d397712b CM |
246 | struct rb_node **p = &root->rb_node; |
247 | struct rb_node *parent = NULL; | |
6af118ce CM |
248 | struct extent_buffer *eb; |
249 | ||
d397712b | 250 | while (*p) { |
6af118ce CM |
251 | parent = *p; |
252 | eb = rb_entry(parent, struct extent_buffer, rb_node); | |
253 | ||
254 | if (offset < eb->start) | |
255 | p = &(*p)->rb_left; | |
256 | else if (offset > eb->start) | |
257 | p = &(*p)->rb_right; | |
258 | else | |
259 | return eb; | |
260 | } | |
261 | ||
262 | rb_link_node(node, parent, p); | |
263 | rb_insert_color(node, root); | |
264 | return NULL; | |
265 | } | |
266 | ||
267 | static struct extent_buffer *buffer_search(struct extent_io_tree *tree, | |
268 | u64 offset) | |
269 | { | |
270 | struct rb_root *root = &tree->buffer; | |
d397712b | 271 | struct rb_node *n = root->rb_node; |
6af118ce CM |
272 | struct extent_buffer *eb; |
273 | ||
d397712b | 274 | while (n) { |
6af118ce CM |
275 | eb = rb_entry(n, struct extent_buffer, rb_node); |
276 | if (offset < eb->start) | |
277 | n = n->rb_left; | |
278 | else if (offset > eb->start) | |
279 | n = n->rb_right; | |
280 | else | |
281 | return eb; | |
282 | } | |
283 | return NULL; | |
284 | } | |
285 | ||
d1310b2e CM |
286 | /* |
287 | * utility function to look for merge candidates inside a given range. | |
288 | * Any extents with matching state are merged together into a single | |
289 | * extent in the tree. Extents with EXTENT_IO in their state field | |
290 | * are not merged because the end_io handlers need to be able to do | |
291 | * operations on them without sleeping (or doing allocations/splits). | |
292 | * | |
293 | * This should be called with the tree lock held. | |
294 | */ | |
295 | static int merge_state(struct extent_io_tree *tree, | |
296 | struct extent_state *state) | |
297 | { | |
298 | struct extent_state *other; | |
299 | struct rb_node *other_node; | |
300 | ||
5b21f2ed | 301 | if (state->state & (EXTENT_IOBITS | EXTENT_BOUNDARY)) |
d1310b2e CM |
302 | return 0; |
303 | ||
304 | other_node = rb_prev(&state->rb_node); | |
305 | if (other_node) { | |
306 | other = rb_entry(other_node, struct extent_state, rb_node); | |
307 | if (other->end == state->start - 1 && | |
308 | other->state == state->state) { | |
309 | state->start = other->start; | |
70dec807 | 310 | other->tree = NULL; |
d1310b2e CM |
311 | rb_erase(&other->rb_node, &tree->state); |
312 | free_extent_state(other); | |
313 | } | |
314 | } | |
315 | other_node = rb_next(&state->rb_node); | |
316 | if (other_node) { | |
317 | other = rb_entry(other_node, struct extent_state, rb_node); | |
318 | if (other->start == state->end + 1 && | |
319 | other->state == state->state) { | |
320 | other->start = state->start; | |
70dec807 | 321 | state->tree = NULL; |
d1310b2e CM |
322 | rb_erase(&state->rb_node, &tree->state); |
323 | free_extent_state(state); | |
324 | } | |
325 | } | |
326 | return 0; | |
327 | } | |
328 | ||
291d673e CM |
329 | static void set_state_cb(struct extent_io_tree *tree, |
330 | struct extent_state *state, | |
331 | unsigned long bits) | |
332 | { | |
333 | if (tree->ops && tree->ops->set_bit_hook) { | |
334 | tree->ops->set_bit_hook(tree->mapping->host, state->start, | |
b0c68f8b | 335 | state->end, state->state, bits); |
291d673e CM |
336 | } |
337 | } | |
338 | ||
339 | static void clear_state_cb(struct extent_io_tree *tree, | |
340 | struct extent_state *state, | |
341 | unsigned long bits) | |
342 | { | |
c584482b | 343 | if (tree->ops && tree->ops->clear_bit_hook) { |
291d673e | 344 | tree->ops->clear_bit_hook(tree->mapping->host, state->start, |
b0c68f8b | 345 | state->end, state->state, bits); |
291d673e CM |
346 | } |
347 | } | |
348 | ||
d1310b2e CM |
349 | /* |
350 | * insert an extent_state struct into the tree. 'bits' are set on the | |
351 | * struct before it is inserted. | |
352 | * | |
353 | * This may return -EEXIST if the extent is already there, in which case the | |
354 | * state struct is freed. | |
355 | * | |
356 | * The tree lock is not taken internally. This is a utility function and | |
357 | * probably isn't what you want to call (see set/clear_extent_bit). | |
358 | */ | |
359 | static int insert_state(struct extent_io_tree *tree, | |
360 | struct extent_state *state, u64 start, u64 end, | |
361 | int bits) | |
362 | { | |
363 | struct rb_node *node; | |
364 | ||
365 | if (end < start) { | |
d397712b CM |
366 | printk(KERN_ERR "btrfs end < start %llu %llu\n", |
367 | (unsigned long long)end, | |
368 | (unsigned long long)start); | |
d1310b2e CM |
369 | WARN_ON(1); |
370 | } | |
371 | if (bits & EXTENT_DIRTY) | |
372 | tree->dirty_bytes += end - start + 1; | |
b0c68f8b | 373 | set_state_cb(tree, state, bits); |
d1310b2e CM |
374 | state->state |= bits; |
375 | state->start = start; | |
376 | state->end = end; | |
377 | node = tree_insert(&tree->state, end, &state->rb_node); | |
378 | if (node) { | |
379 | struct extent_state *found; | |
380 | found = rb_entry(node, struct extent_state, rb_node); | |
d397712b CM |
381 | printk(KERN_ERR "btrfs found node %llu %llu on insert of " |
382 | "%llu %llu\n", (unsigned long long)found->start, | |
383 | (unsigned long long)found->end, | |
384 | (unsigned long long)start, (unsigned long long)end); | |
d1310b2e CM |
385 | free_extent_state(state); |
386 | return -EEXIST; | |
387 | } | |
70dec807 | 388 | state->tree = tree; |
d1310b2e CM |
389 | merge_state(tree, state); |
390 | return 0; | |
391 | } | |
392 | ||
393 | /* | |
394 | * split a given extent state struct in two, inserting the preallocated | |
395 | * struct 'prealloc' as the newly created second half. 'split' indicates an | |
396 | * offset inside 'orig' where it should be split. | |
397 | * | |
398 | * Before calling, | |
399 | * the tree has 'orig' at [orig->start, orig->end]. After calling, there | |
400 | * are two extent state structs in the tree: | |
401 | * prealloc: [orig->start, split - 1] | |
402 | * orig: [ split, orig->end ] | |
403 | * | |
404 | * The tree locks are not taken by this function. They need to be held | |
405 | * by the caller. | |
406 | */ | |
407 | static int split_state(struct extent_io_tree *tree, struct extent_state *orig, | |
408 | struct extent_state *prealloc, u64 split) | |
409 | { | |
410 | struct rb_node *node; | |
411 | prealloc->start = orig->start; | |
412 | prealloc->end = split - 1; | |
413 | prealloc->state = orig->state; | |
414 | orig->start = split; | |
415 | ||
416 | node = tree_insert(&tree->state, prealloc->end, &prealloc->rb_node); | |
417 | if (node) { | |
418 | struct extent_state *found; | |
419 | found = rb_entry(node, struct extent_state, rb_node); | |
d1310b2e CM |
420 | free_extent_state(prealloc); |
421 | return -EEXIST; | |
422 | } | |
70dec807 | 423 | prealloc->tree = tree; |
d1310b2e CM |
424 | return 0; |
425 | } | |
426 | ||
427 | /* | |
428 | * utility function to clear some bits in an extent state struct. | |
429 | * it will optionally wake up any one waiting on this state (wake == 1), or | |
430 | * forcibly remove the state from the tree (delete == 1). | |
431 | * | |
432 | * If no bits are set on the state struct after clearing things, the | |
433 | * struct is freed and removed from the tree | |
434 | */ | |
435 | static int clear_state_bit(struct extent_io_tree *tree, | |
436 | struct extent_state *state, int bits, int wake, | |
437 | int delete) | |
438 | { | |
439 | int ret = state->state & bits; | |
440 | ||
441 | if ((bits & EXTENT_DIRTY) && (state->state & EXTENT_DIRTY)) { | |
442 | u64 range = state->end - state->start + 1; | |
443 | WARN_ON(range > tree->dirty_bytes); | |
444 | tree->dirty_bytes -= range; | |
445 | } | |
291d673e | 446 | clear_state_cb(tree, state, bits); |
b0c68f8b | 447 | state->state &= ~bits; |
d1310b2e CM |
448 | if (wake) |
449 | wake_up(&state->wq); | |
450 | if (delete || state->state == 0) { | |
70dec807 | 451 | if (state->tree) { |
ae9d1285 | 452 | clear_state_cb(tree, state, state->state); |
d1310b2e | 453 | rb_erase(&state->rb_node, &tree->state); |
70dec807 | 454 | state->tree = NULL; |
d1310b2e CM |
455 | free_extent_state(state); |
456 | } else { | |
457 | WARN_ON(1); | |
458 | } | |
459 | } else { | |
460 | merge_state(tree, state); | |
461 | } | |
462 | return ret; | |
463 | } | |
464 | ||
465 | /* | |
466 | * clear some bits on a range in the tree. This may require splitting | |
467 | * or inserting elements in the tree, so the gfp mask is used to | |
468 | * indicate which allocations or sleeping are allowed. | |
469 | * | |
470 | * pass 'wake' == 1 to kick any sleepers, and 'delete' == 1 to remove | |
471 | * the given range from the tree regardless of state (ie for truncate). | |
472 | * | |
473 | * the range [start, end] is inclusive. | |
474 | * | |
475 | * This takes the tree lock, and returns < 0 on error, > 0 if any of the | |
476 | * bits were already set, or zero if none of the bits were already set. | |
477 | */ | |
478 | int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, | |
479 | int bits, int wake, int delete, gfp_t mask) | |
480 | { | |
481 | struct extent_state *state; | |
482 | struct extent_state *prealloc = NULL; | |
483 | struct rb_node *node; | |
d1310b2e CM |
484 | int err; |
485 | int set = 0; | |
486 | ||
487 | again: | |
488 | if (!prealloc && (mask & __GFP_WAIT)) { | |
489 | prealloc = alloc_extent_state(mask); | |
490 | if (!prealloc) | |
491 | return -ENOMEM; | |
492 | } | |
493 | ||
cad321ad | 494 | spin_lock(&tree->lock); |
d1310b2e CM |
495 | /* |
496 | * this search will find the extents that end after | |
497 | * our range starts | |
498 | */ | |
80ea96b1 | 499 | node = tree_search(tree, start); |
d1310b2e CM |
500 | if (!node) |
501 | goto out; | |
502 | state = rb_entry(node, struct extent_state, rb_node); | |
503 | if (state->start > end) | |
504 | goto out; | |
505 | WARN_ON(state->end < start); | |
506 | ||
507 | /* | |
508 | * | ---- desired range ---- | | |
509 | * | state | or | |
510 | * | ------------- state -------------- | | |
511 | * | |
512 | * We need to split the extent we found, and may flip | |
513 | * bits on second half. | |
514 | * | |
515 | * If the extent we found extends past our range, we | |
516 | * just split and search again. It'll get split again | |
517 | * the next time though. | |
518 | * | |
519 | * If the extent we found is inside our range, we clear | |
520 | * the desired bit on it. | |
521 | */ | |
522 | ||
523 | if (state->start < start) { | |
70dec807 CM |
524 | if (!prealloc) |
525 | prealloc = alloc_extent_state(GFP_ATOMIC); | |
d1310b2e CM |
526 | err = split_state(tree, state, prealloc, start); |
527 | BUG_ON(err == -EEXIST); | |
528 | prealloc = NULL; | |
529 | if (err) | |
530 | goto out; | |
531 | if (state->end <= end) { | |
532 | start = state->end + 1; | |
533 | set |= clear_state_bit(tree, state, bits, | |
534 | wake, delete); | |
535 | } else { | |
536 | start = state->start; | |
537 | } | |
538 | goto search_again; | |
539 | } | |
540 | /* | |
541 | * | ---- desired range ---- | | |
542 | * | state | | |
543 | * We need to split the extent, and clear the bit | |
544 | * on the first half | |
545 | */ | |
546 | if (state->start <= end && state->end > end) { | |
70dec807 CM |
547 | if (!prealloc) |
548 | prealloc = alloc_extent_state(GFP_ATOMIC); | |
d1310b2e CM |
549 | err = split_state(tree, state, prealloc, end + 1); |
550 | BUG_ON(err == -EEXIST); | |
551 | ||
552 | if (wake) | |
553 | wake_up(&state->wq); | |
554 | set |= clear_state_bit(tree, prealloc, bits, | |
555 | wake, delete); | |
556 | prealloc = NULL; | |
557 | goto out; | |
558 | } | |
559 | ||
560 | start = state->end + 1; | |
561 | set |= clear_state_bit(tree, state, bits, wake, delete); | |
562 | goto search_again; | |
563 | ||
564 | out: | |
cad321ad | 565 | spin_unlock(&tree->lock); |
d1310b2e CM |
566 | if (prealloc) |
567 | free_extent_state(prealloc); | |
568 | ||
569 | return set; | |
570 | ||
571 | search_again: | |
572 | if (start > end) | |
573 | goto out; | |
cad321ad | 574 | spin_unlock(&tree->lock); |
d1310b2e CM |
575 | if (mask & __GFP_WAIT) |
576 | cond_resched(); | |
577 | goto again; | |
578 | } | |
d1310b2e CM |
579 | |
580 | static int wait_on_state(struct extent_io_tree *tree, | |
581 | struct extent_state *state) | |
641f5219 CH |
582 | __releases(tree->lock) |
583 | __acquires(tree->lock) | |
d1310b2e CM |
584 | { |
585 | DEFINE_WAIT(wait); | |
586 | prepare_to_wait(&state->wq, &wait, TASK_UNINTERRUPTIBLE); | |
cad321ad | 587 | spin_unlock(&tree->lock); |
d1310b2e | 588 | schedule(); |
cad321ad | 589 | spin_lock(&tree->lock); |
d1310b2e CM |
590 | finish_wait(&state->wq, &wait); |
591 | return 0; | |
592 | } | |
593 | ||
594 | /* | |
595 | * waits for one or more bits to clear on a range in the state tree. | |
596 | * The range [start, end] is inclusive. | |
597 | * The tree lock is taken by this function | |
598 | */ | |
599 | int wait_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, int bits) | |
600 | { | |
601 | struct extent_state *state; | |
602 | struct rb_node *node; | |
603 | ||
cad321ad | 604 | spin_lock(&tree->lock); |
d1310b2e CM |
605 | again: |
606 | while (1) { | |
607 | /* | |
608 | * this search will find all the extents that end after | |
609 | * our range starts | |
610 | */ | |
80ea96b1 | 611 | node = tree_search(tree, start); |
d1310b2e CM |
612 | if (!node) |
613 | break; | |
614 | ||
615 | state = rb_entry(node, struct extent_state, rb_node); | |
616 | ||
617 | if (state->start > end) | |
618 | goto out; | |
619 | ||
620 | if (state->state & bits) { | |
621 | start = state->start; | |
622 | atomic_inc(&state->refs); | |
623 | wait_on_state(tree, state); | |
624 | free_extent_state(state); | |
625 | goto again; | |
626 | } | |
627 | start = state->end + 1; | |
628 | ||
629 | if (start > end) | |
630 | break; | |
631 | ||
632 | if (need_resched()) { | |
cad321ad | 633 | spin_unlock(&tree->lock); |
d1310b2e | 634 | cond_resched(); |
cad321ad | 635 | spin_lock(&tree->lock); |
d1310b2e CM |
636 | } |
637 | } | |
638 | out: | |
cad321ad | 639 | spin_unlock(&tree->lock); |
d1310b2e CM |
640 | return 0; |
641 | } | |
d1310b2e CM |
642 | |
643 | static void set_state_bits(struct extent_io_tree *tree, | |
644 | struct extent_state *state, | |
645 | int bits) | |
646 | { | |
647 | if ((bits & EXTENT_DIRTY) && !(state->state & EXTENT_DIRTY)) { | |
648 | u64 range = state->end - state->start + 1; | |
649 | tree->dirty_bytes += range; | |
650 | } | |
291d673e | 651 | set_state_cb(tree, state, bits); |
b0c68f8b | 652 | state->state |= bits; |
d1310b2e CM |
653 | } |
654 | ||
655 | /* | |
656 | * set some bits on a range in the tree. This may require allocations | |
657 | * or sleeping, so the gfp mask is used to indicate what is allowed. | |
658 | * | |
659 | * If 'exclusive' == 1, this will fail with -EEXIST if some part of the | |
660 | * range already has the desired bits set. The start of the existing | |
661 | * range is returned in failed_start in this case. | |
662 | * | |
663 | * [start, end] is inclusive | |
664 | * This takes the tree lock. | |
665 | */ | |
d397712b CM |
666 | static int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, |
667 | int bits, int exclusive, u64 *failed_start, | |
668 | gfp_t mask) | |
d1310b2e CM |
669 | { |
670 | struct extent_state *state; | |
671 | struct extent_state *prealloc = NULL; | |
672 | struct rb_node *node; | |
d1310b2e CM |
673 | int err = 0; |
674 | int set; | |
675 | u64 last_start; | |
676 | u64 last_end; | |
677 | again: | |
678 | if (!prealloc && (mask & __GFP_WAIT)) { | |
679 | prealloc = alloc_extent_state(mask); | |
680 | if (!prealloc) | |
681 | return -ENOMEM; | |
682 | } | |
683 | ||
cad321ad | 684 | spin_lock(&tree->lock); |
d1310b2e CM |
685 | /* |
686 | * this search will find all the extents that end after | |
687 | * our range starts. | |
688 | */ | |
80ea96b1 | 689 | node = tree_search(tree, start); |
d1310b2e CM |
690 | if (!node) { |
691 | err = insert_state(tree, prealloc, start, end, bits); | |
692 | prealloc = NULL; | |
693 | BUG_ON(err == -EEXIST); | |
694 | goto out; | |
695 | } | |
696 | ||
697 | state = rb_entry(node, struct extent_state, rb_node); | |
698 | last_start = state->start; | |
699 | last_end = state->end; | |
700 | ||
701 | /* | |
702 | * | ---- desired range ---- | | |
703 | * | state | | |
704 | * | |
705 | * Just lock what we found and keep going | |
706 | */ | |
707 | if (state->start == start && state->end <= end) { | |
708 | set = state->state & bits; | |
709 | if (set && exclusive) { | |
710 | *failed_start = state->start; | |
711 | err = -EEXIST; | |
712 | goto out; | |
713 | } | |
714 | set_state_bits(tree, state, bits); | |
715 | start = state->end + 1; | |
716 | merge_state(tree, state); | |
717 | goto search_again; | |
718 | } | |
719 | ||
720 | /* | |
721 | * | ---- desired range ---- | | |
722 | * | state | | |
723 | * or | |
724 | * | ------------- state -------------- | | |
725 | * | |
726 | * We need to split the extent we found, and may flip bits on | |
727 | * second half. | |
728 | * | |
729 | * If the extent we found extends past our | |
730 | * range, we just split and search again. It'll get split | |
731 | * again the next time though. | |
732 | * | |
733 | * If the extent we found is inside our range, we set the | |
734 | * desired bit on it. | |
735 | */ | |
736 | if (state->start < start) { | |
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, start); | |
744 | BUG_ON(err == -EEXIST); | |
745 | prealloc = NULL; | |
746 | if (err) | |
747 | goto out; | |
748 | if (state->end <= end) { | |
749 | set_state_bits(tree, state, bits); | |
750 | start = state->end + 1; | |
751 | merge_state(tree, state); | |
752 | } else { | |
753 | start = state->start; | |
754 | } | |
755 | goto search_again; | |
756 | } | |
757 | /* | |
758 | * | ---- desired range ---- | | |
759 | * | state | or | state | | |
760 | * | |
761 | * There's a hole, we need to insert something in it and | |
762 | * ignore the extent we found. | |
763 | */ | |
764 | if (state->start > start) { | |
765 | u64 this_end; | |
766 | if (end < last_start) | |
767 | this_end = end; | |
768 | else | |
d397712b | 769 | this_end = last_start - 1; |
d1310b2e CM |
770 | err = insert_state(tree, prealloc, start, this_end, |
771 | bits); | |
772 | prealloc = NULL; | |
773 | BUG_ON(err == -EEXIST); | |
774 | if (err) | |
775 | goto out; | |
776 | start = this_end + 1; | |
777 | goto search_again; | |
778 | } | |
779 | /* | |
780 | * | ---- desired range ---- | | |
781 | * | state | | |
782 | * We need to split the extent, and set the bit | |
783 | * on the first half | |
784 | */ | |
785 | if (state->start <= end && state->end > end) { | |
786 | set = state->state & bits; | |
787 | if (exclusive && set) { | |
788 | *failed_start = start; | |
789 | err = -EEXIST; | |
790 | goto out; | |
791 | } | |
792 | err = split_state(tree, state, prealloc, end + 1); | |
793 | BUG_ON(err == -EEXIST); | |
794 | ||
795 | set_state_bits(tree, prealloc, bits); | |
796 | merge_state(tree, prealloc); | |
797 | prealloc = NULL; | |
798 | goto out; | |
799 | } | |
800 | ||
801 | goto search_again; | |
802 | ||
803 | out: | |
cad321ad | 804 | spin_unlock(&tree->lock); |
d1310b2e CM |
805 | if (prealloc) |
806 | free_extent_state(prealloc); | |
807 | ||
808 | return err; | |
809 | ||
810 | search_again: | |
811 | if (start > end) | |
812 | goto out; | |
cad321ad | 813 | spin_unlock(&tree->lock); |
d1310b2e CM |
814 | if (mask & __GFP_WAIT) |
815 | cond_resched(); | |
816 | goto again; | |
817 | } | |
d1310b2e CM |
818 | |
819 | /* wrappers around set/clear extent bit */ | |
820 | int set_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end, | |
821 | gfp_t mask) | |
822 | { | |
823 | return set_extent_bit(tree, start, end, EXTENT_DIRTY, 0, NULL, | |
824 | mask); | |
825 | } | |
d1310b2e | 826 | |
e6dcd2dc CM |
827 | int set_extent_ordered(struct extent_io_tree *tree, u64 start, u64 end, |
828 | gfp_t mask) | |
829 | { | |
830 | return set_extent_bit(tree, start, end, EXTENT_ORDERED, 0, NULL, mask); | |
831 | } | |
e6dcd2dc | 832 | |
d1310b2e CM |
833 | int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, |
834 | int bits, gfp_t mask) | |
835 | { | |
836 | return set_extent_bit(tree, start, end, bits, 0, NULL, | |
837 | mask); | |
838 | } | |
d1310b2e CM |
839 | |
840 | int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, | |
841 | int bits, gfp_t mask) | |
842 | { | |
843 | return clear_extent_bit(tree, start, end, bits, 0, 0, mask); | |
844 | } | |
d1310b2e CM |
845 | |
846 | int set_extent_delalloc(struct extent_io_tree *tree, u64 start, u64 end, | |
847 | gfp_t mask) | |
848 | { | |
849 | return set_extent_bit(tree, start, end, | |
e6dcd2dc CM |
850 | EXTENT_DELALLOC | EXTENT_DIRTY, |
851 | 0, NULL, mask); | |
d1310b2e | 852 | } |
d1310b2e CM |
853 | |
854 | int clear_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end, | |
855 | gfp_t mask) | |
856 | { | |
857 | return clear_extent_bit(tree, start, end, | |
858 | EXTENT_DIRTY | EXTENT_DELALLOC, 0, 0, mask); | |
859 | } | |
d1310b2e | 860 | |
e6dcd2dc CM |
861 | int clear_extent_ordered(struct extent_io_tree *tree, u64 start, u64 end, |
862 | gfp_t mask) | |
863 | { | |
864 | return clear_extent_bit(tree, start, end, EXTENT_ORDERED, 1, 0, mask); | |
865 | } | |
e6dcd2dc | 866 | |
d1310b2e CM |
867 | int set_extent_new(struct extent_io_tree *tree, u64 start, u64 end, |
868 | gfp_t mask) | |
869 | { | |
870 | return set_extent_bit(tree, start, end, EXTENT_NEW, 0, NULL, | |
871 | mask); | |
872 | } | |
d1310b2e | 873 | |
b2950863 | 874 | static int clear_extent_new(struct extent_io_tree *tree, u64 start, u64 end, |
d1310b2e CM |
875 | gfp_t mask) |
876 | { | |
877 | return clear_extent_bit(tree, start, end, EXTENT_NEW, 0, 0, mask); | |
878 | } | |
d1310b2e CM |
879 | |
880 | int set_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end, | |
881 | gfp_t mask) | |
882 | { | |
883 | return set_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, NULL, | |
884 | mask); | |
885 | } | |
d1310b2e | 886 | |
d397712b CM |
887 | static int clear_extent_uptodate(struct extent_io_tree *tree, u64 start, |
888 | u64 end, gfp_t mask) | |
d1310b2e CM |
889 | { |
890 | return clear_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, 0, mask); | |
891 | } | |
d1310b2e | 892 | |
b2950863 | 893 | static int set_extent_writeback(struct extent_io_tree *tree, u64 start, u64 end, |
d1310b2e CM |
894 | gfp_t mask) |
895 | { | |
896 | return set_extent_bit(tree, start, end, EXTENT_WRITEBACK, | |
897 | 0, NULL, mask); | |
898 | } | |
d1310b2e | 899 | |
d397712b CM |
900 | static int clear_extent_writeback(struct extent_io_tree *tree, u64 start, |
901 | u64 end, gfp_t mask) | |
d1310b2e CM |
902 | { |
903 | return clear_extent_bit(tree, start, end, EXTENT_WRITEBACK, 1, 0, mask); | |
904 | } | |
d1310b2e CM |
905 | |
906 | int wait_on_extent_writeback(struct extent_io_tree *tree, u64 start, u64 end) | |
907 | { | |
908 | return wait_extent_bit(tree, start, end, EXTENT_WRITEBACK); | |
909 | } | |
d1310b2e | 910 | |
d352ac68 CM |
911 | /* |
912 | * either insert or lock state struct between start and end use mask to tell | |
913 | * us if waiting is desired. | |
914 | */ | |
d1310b2e CM |
915 | int lock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask) |
916 | { | |
917 | int err; | |
918 | u64 failed_start; | |
919 | while (1) { | |
920 | err = set_extent_bit(tree, start, end, EXTENT_LOCKED, 1, | |
921 | &failed_start, mask); | |
922 | if (err == -EEXIST && (mask & __GFP_WAIT)) { | |
923 | wait_extent_bit(tree, failed_start, end, EXTENT_LOCKED); | |
924 | start = failed_start; | |
925 | } else { | |
926 | break; | |
927 | } | |
928 | WARN_ON(start > end); | |
929 | } | |
930 | return err; | |
931 | } | |
d1310b2e | 932 | |
25179201 JB |
933 | int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end, |
934 | gfp_t mask) | |
935 | { | |
936 | int err; | |
937 | u64 failed_start; | |
938 | ||
939 | err = set_extent_bit(tree, start, end, EXTENT_LOCKED, 1, | |
940 | &failed_start, mask); | |
6643558d YZ |
941 | if (err == -EEXIST) { |
942 | if (failed_start > start) | |
943 | clear_extent_bit(tree, start, failed_start - 1, | |
944 | EXTENT_LOCKED, 1, 0, mask); | |
25179201 | 945 | return 0; |
6643558d | 946 | } |
25179201 JB |
947 | return 1; |
948 | } | |
25179201 | 949 | |
d1310b2e CM |
950 | int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end, |
951 | gfp_t mask) | |
952 | { | |
953 | return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, mask); | |
954 | } | |
d1310b2e CM |
955 | |
956 | /* | |
957 | * helper function to set pages and extents in the tree dirty | |
958 | */ | |
959 | int set_range_dirty(struct extent_io_tree *tree, u64 start, u64 end) | |
960 | { | |
961 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
962 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
963 | struct page *page; | |
964 | ||
965 | while (index <= end_index) { | |
966 | page = find_get_page(tree->mapping, index); | |
967 | BUG_ON(!page); | |
968 | __set_page_dirty_nobuffers(page); | |
969 | page_cache_release(page); | |
970 | index++; | |
971 | } | |
972 | set_extent_dirty(tree, start, end, GFP_NOFS); | |
973 | return 0; | |
974 | } | |
d1310b2e CM |
975 | |
976 | /* | |
977 | * helper function to set both pages and extents in the tree writeback | |
978 | */ | |
b2950863 | 979 | static int set_range_writeback(struct extent_io_tree *tree, u64 start, u64 end) |
d1310b2e CM |
980 | { |
981 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
982 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
983 | struct page *page; | |
984 | ||
985 | while (index <= end_index) { | |
986 | page = find_get_page(tree->mapping, index); | |
987 | BUG_ON(!page); | |
988 | set_page_writeback(page); | |
989 | page_cache_release(page); | |
990 | index++; | |
991 | } | |
992 | set_extent_writeback(tree, start, end, GFP_NOFS); | |
993 | return 0; | |
994 | } | |
d1310b2e | 995 | |
d352ac68 CM |
996 | /* |
997 | * find the first offset in the io tree with 'bits' set. zero is | |
998 | * returned if we find something, and *start_ret and *end_ret are | |
999 | * set to reflect the state struct that was found. | |
1000 | * | |
1001 | * If nothing was found, 1 is returned, < 0 on error | |
1002 | */ | |
d1310b2e CM |
1003 | int find_first_extent_bit(struct extent_io_tree *tree, u64 start, |
1004 | u64 *start_ret, u64 *end_ret, int bits) | |
1005 | { | |
1006 | struct rb_node *node; | |
1007 | struct extent_state *state; | |
1008 | int ret = 1; | |
1009 | ||
cad321ad | 1010 | spin_lock(&tree->lock); |
d1310b2e CM |
1011 | /* |
1012 | * this search will find all the extents that end after | |
1013 | * our range starts. | |
1014 | */ | |
80ea96b1 | 1015 | node = tree_search(tree, start); |
d397712b | 1016 | if (!node) |
d1310b2e | 1017 | goto out; |
d1310b2e | 1018 | |
d397712b | 1019 | while (1) { |
d1310b2e CM |
1020 | state = rb_entry(node, struct extent_state, rb_node); |
1021 | if (state->end >= start && (state->state & bits)) { | |
1022 | *start_ret = state->start; | |
1023 | *end_ret = state->end; | |
1024 | ret = 0; | |
1025 | break; | |
1026 | } | |
1027 | node = rb_next(node); | |
1028 | if (!node) | |
1029 | break; | |
1030 | } | |
1031 | out: | |
cad321ad | 1032 | spin_unlock(&tree->lock); |
d1310b2e CM |
1033 | return ret; |
1034 | } | |
d1310b2e | 1035 | |
d352ac68 CM |
1036 | /* find the first state struct with 'bits' set after 'start', and |
1037 | * return it. tree->lock must be held. NULL will returned if | |
1038 | * nothing was found after 'start' | |
1039 | */ | |
d7fc640e CM |
1040 | struct extent_state *find_first_extent_bit_state(struct extent_io_tree *tree, |
1041 | u64 start, int bits) | |
1042 | { | |
1043 | struct rb_node *node; | |
1044 | struct extent_state *state; | |
1045 | ||
1046 | /* | |
1047 | * this search will find all the extents that end after | |
1048 | * our range starts. | |
1049 | */ | |
1050 | node = tree_search(tree, start); | |
d397712b | 1051 | if (!node) |
d7fc640e | 1052 | goto out; |
d7fc640e | 1053 | |
d397712b | 1054 | while (1) { |
d7fc640e | 1055 | state = rb_entry(node, struct extent_state, rb_node); |
d397712b | 1056 | if (state->end >= start && (state->state & bits)) |
d7fc640e | 1057 | return state; |
d397712b | 1058 | |
d7fc640e CM |
1059 | node = rb_next(node); |
1060 | if (!node) | |
1061 | break; | |
1062 | } | |
1063 | out: | |
1064 | return NULL; | |
1065 | } | |
d7fc640e | 1066 | |
d352ac68 CM |
1067 | /* |
1068 | * find a contiguous range of bytes in the file marked as delalloc, not | |
1069 | * more than 'max_bytes'. start and end are used to return the range, | |
1070 | * | |
1071 | * 1 is returned if we find something, 0 if nothing was in the tree | |
1072 | */ | |
c8b97818 CM |
1073 | static noinline u64 find_delalloc_range(struct extent_io_tree *tree, |
1074 | u64 *start, u64 *end, u64 max_bytes) | |
d1310b2e CM |
1075 | { |
1076 | struct rb_node *node; | |
1077 | struct extent_state *state; | |
1078 | u64 cur_start = *start; | |
1079 | u64 found = 0; | |
1080 | u64 total_bytes = 0; | |
1081 | ||
cad321ad | 1082 | spin_lock(&tree->lock); |
c8b97818 | 1083 | |
d1310b2e CM |
1084 | /* |
1085 | * this search will find all the extents that end after | |
1086 | * our range starts. | |
1087 | */ | |
80ea96b1 | 1088 | node = tree_search(tree, cur_start); |
2b114d1d | 1089 | if (!node) { |
3b951516 CM |
1090 | if (!found) |
1091 | *end = (u64)-1; | |
d1310b2e CM |
1092 | goto out; |
1093 | } | |
1094 | ||
d397712b | 1095 | while (1) { |
d1310b2e | 1096 | state = rb_entry(node, struct extent_state, rb_node); |
5b21f2ed ZY |
1097 | if (found && (state->start != cur_start || |
1098 | (state->state & EXTENT_BOUNDARY))) { | |
d1310b2e CM |
1099 | goto out; |
1100 | } | |
1101 | if (!(state->state & EXTENT_DELALLOC)) { | |
1102 | if (!found) | |
1103 | *end = state->end; | |
1104 | goto out; | |
1105 | } | |
d1310b2e CM |
1106 | if (!found) |
1107 | *start = state->start; | |
1108 | found++; | |
1109 | *end = state->end; | |
1110 | cur_start = state->end + 1; | |
1111 | node = rb_next(node); | |
1112 | if (!node) | |
1113 | break; | |
1114 | total_bytes += state->end - state->start + 1; | |
1115 | if (total_bytes >= max_bytes) | |
1116 | break; | |
1117 | } | |
1118 | out: | |
cad321ad | 1119 | spin_unlock(&tree->lock); |
d1310b2e CM |
1120 | return found; |
1121 | } | |
1122 | ||
c8b97818 CM |
1123 | static noinline int __unlock_for_delalloc(struct inode *inode, |
1124 | struct page *locked_page, | |
1125 | u64 start, u64 end) | |
1126 | { | |
1127 | int ret; | |
1128 | struct page *pages[16]; | |
1129 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1130 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
1131 | unsigned long nr_pages = end_index - index + 1; | |
1132 | int i; | |
1133 | ||
1134 | if (index == locked_page->index && end_index == index) | |
1135 | return 0; | |
1136 | ||
d397712b | 1137 | while (nr_pages > 0) { |
c8b97818 | 1138 | ret = find_get_pages_contig(inode->i_mapping, index, |
5b050f04 CM |
1139 | min_t(unsigned long, nr_pages, |
1140 | ARRAY_SIZE(pages)), pages); | |
c8b97818 CM |
1141 | for (i = 0; i < ret; i++) { |
1142 | if (pages[i] != locked_page) | |
1143 | unlock_page(pages[i]); | |
1144 | page_cache_release(pages[i]); | |
1145 | } | |
1146 | nr_pages -= ret; | |
1147 | index += ret; | |
1148 | cond_resched(); | |
1149 | } | |
1150 | return 0; | |
1151 | } | |
1152 | ||
1153 | static noinline int lock_delalloc_pages(struct inode *inode, | |
1154 | struct page *locked_page, | |
1155 | u64 delalloc_start, | |
1156 | u64 delalloc_end) | |
1157 | { | |
1158 | unsigned long index = delalloc_start >> PAGE_CACHE_SHIFT; | |
1159 | unsigned long start_index = index; | |
1160 | unsigned long end_index = delalloc_end >> PAGE_CACHE_SHIFT; | |
1161 | unsigned long pages_locked = 0; | |
1162 | struct page *pages[16]; | |
1163 | unsigned long nrpages; | |
1164 | int ret; | |
1165 | int i; | |
1166 | ||
1167 | /* the caller is responsible for locking the start index */ | |
1168 | if (index == locked_page->index && index == end_index) | |
1169 | return 0; | |
1170 | ||
1171 | /* skip the page at the start index */ | |
1172 | nrpages = end_index - index + 1; | |
d397712b | 1173 | while (nrpages > 0) { |
c8b97818 | 1174 | ret = find_get_pages_contig(inode->i_mapping, index, |
5b050f04 CM |
1175 | min_t(unsigned long, |
1176 | nrpages, ARRAY_SIZE(pages)), pages); | |
c8b97818 CM |
1177 | if (ret == 0) { |
1178 | ret = -EAGAIN; | |
1179 | goto done; | |
1180 | } | |
1181 | /* now we have an array of pages, lock them all */ | |
1182 | for (i = 0; i < ret; i++) { | |
1183 | /* | |
1184 | * the caller is taking responsibility for | |
1185 | * locked_page | |
1186 | */ | |
771ed689 | 1187 | if (pages[i] != locked_page) { |
c8b97818 | 1188 | lock_page(pages[i]); |
f2b1c41c CM |
1189 | if (!PageDirty(pages[i]) || |
1190 | pages[i]->mapping != inode->i_mapping) { | |
771ed689 CM |
1191 | ret = -EAGAIN; |
1192 | unlock_page(pages[i]); | |
1193 | page_cache_release(pages[i]); | |
1194 | goto done; | |
1195 | } | |
1196 | } | |
c8b97818 | 1197 | page_cache_release(pages[i]); |
771ed689 | 1198 | pages_locked++; |
c8b97818 | 1199 | } |
c8b97818 CM |
1200 | nrpages -= ret; |
1201 | index += ret; | |
1202 | cond_resched(); | |
1203 | } | |
1204 | ret = 0; | |
1205 | done: | |
1206 | if (ret && pages_locked) { | |
1207 | __unlock_for_delalloc(inode, locked_page, | |
1208 | delalloc_start, | |
1209 | ((u64)(start_index + pages_locked - 1)) << | |
1210 | PAGE_CACHE_SHIFT); | |
1211 | } | |
1212 | return ret; | |
1213 | } | |
1214 | ||
1215 | /* | |
1216 | * find a contiguous range of bytes in the file marked as delalloc, not | |
1217 | * more than 'max_bytes'. start and end are used to return the range, | |
1218 | * | |
1219 | * 1 is returned if we find something, 0 if nothing was in the tree | |
1220 | */ | |
1221 | static noinline u64 find_lock_delalloc_range(struct inode *inode, | |
1222 | struct extent_io_tree *tree, | |
1223 | struct page *locked_page, | |
1224 | u64 *start, u64 *end, | |
1225 | u64 max_bytes) | |
1226 | { | |
1227 | u64 delalloc_start; | |
1228 | u64 delalloc_end; | |
1229 | u64 found; | |
1230 | int ret; | |
1231 | int loops = 0; | |
1232 | ||
1233 | again: | |
1234 | /* step one, find a bunch of delalloc bytes starting at start */ | |
1235 | delalloc_start = *start; | |
1236 | delalloc_end = 0; | |
1237 | found = find_delalloc_range(tree, &delalloc_start, &delalloc_end, | |
1238 | max_bytes); | |
70b99e69 | 1239 | if (!found || delalloc_end <= *start) { |
c8b97818 CM |
1240 | *start = delalloc_start; |
1241 | *end = delalloc_end; | |
1242 | return found; | |
1243 | } | |
1244 | ||
70b99e69 CM |
1245 | /* |
1246 | * start comes from the offset of locked_page. We have to lock | |
1247 | * pages in order, so we can't process delalloc bytes before | |
1248 | * locked_page | |
1249 | */ | |
d397712b | 1250 | if (delalloc_start < *start) |
70b99e69 | 1251 | delalloc_start = *start; |
70b99e69 | 1252 | |
c8b97818 CM |
1253 | /* |
1254 | * make sure to limit the number of pages we try to lock down | |
1255 | * if we're looping. | |
1256 | */ | |
d397712b | 1257 | if (delalloc_end + 1 - delalloc_start > max_bytes && loops) |
771ed689 | 1258 | delalloc_end = delalloc_start + PAGE_CACHE_SIZE - 1; |
d397712b | 1259 | |
c8b97818 CM |
1260 | /* step two, lock all the pages after the page that has start */ |
1261 | ret = lock_delalloc_pages(inode, locked_page, | |
1262 | delalloc_start, delalloc_end); | |
1263 | if (ret == -EAGAIN) { | |
1264 | /* some of the pages are gone, lets avoid looping by | |
1265 | * shortening the size of the delalloc range we're searching | |
1266 | */ | |
1267 | if (!loops) { | |
1268 | unsigned long offset = (*start) & (PAGE_CACHE_SIZE - 1); | |
1269 | max_bytes = PAGE_CACHE_SIZE - offset; | |
1270 | loops = 1; | |
1271 | goto again; | |
1272 | } else { | |
1273 | found = 0; | |
1274 | goto out_failed; | |
1275 | } | |
1276 | } | |
1277 | BUG_ON(ret); | |
1278 | ||
1279 | /* step three, lock the state bits for the whole range */ | |
1280 | lock_extent(tree, delalloc_start, delalloc_end, GFP_NOFS); | |
1281 | ||
1282 | /* then test to make sure it is all still delalloc */ | |
1283 | ret = test_range_bit(tree, delalloc_start, delalloc_end, | |
1284 | EXTENT_DELALLOC, 1); | |
1285 | if (!ret) { | |
1286 | unlock_extent(tree, delalloc_start, delalloc_end, GFP_NOFS); | |
1287 | __unlock_for_delalloc(inode, locked_page, | |
1288 | delalloc_start, delalloc_end); | |
1289 | cond_resched(); | |
1290 | goto again; | |
1291 | } | |
1292 | *start = delalloc_start; | |
1293 | *end = delalloc_end; | |
1294 | out_failed: | |
1295 | return found; | |
1296 | } | |
1297 | ||
1298 | int extent_clear_unlock_delalloc(struct inode *inode, | |
1299 | struct extent_io_tree *tree, | |
1300 | u64 start, u64 end, struct page *locked_page, | |
771ed689 CM |
1301 | int unlock_pages, |
1302 | int clear_unlock, | |
1303 | int clear_delalloc, int clear_dirty, | |
1304 | int set_writeback, | |
c8b97818 CM |
1305 | int end_writeback) |
1306 | { | |
1307 | int ret; | |
1308 | struct page *pages[16]; | |
1309 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1310 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
1311 | unsigned long nr_pages = end_index - index + 1; | |
1312 | int i; | |
771ed689 | 1313 | int clear_bits = 0; |
c8b97818 | 1314 | |
771ed689 CM |
1315 | if (clear_unlock) |
1316 | clear_bits |= EXTENT_LOCKED; | |
c8b97818 CM |
1317 | if (clear_dirty) |
1318 | clear_bits |= EXTENT_DIRTY; | |
1319 | ||
771ed689 CM |
1320 | if (clear_delalloc) |
1321 | clear_bits |= EXTENT_DELALLOC; | |
1322 | ||
c8b97818 | 1323 | clear_extent_bit(tree, start, end, clear_bits, 1, 0, GFP_NOFS); |
771ed689 CM |
1324 | if (!(unlock_pages || clear_dirty || set_writeback || end_writeback)) |
1325 | return 0; | |
c8b97818 | 1326 | |
d397712b | 1327 | while (nr_pages > 0) { |
c8b97818 | 1328 | ret = find_get_pages_contig(inode->i_mapping, index, |
5b050f04 CM |
1329 | min_t(unsigned long, |
1330 | nr_pages, ARRAY_SIZE(pages)), pages); | |
c8b97818 CM |
1331 | for (i = 0; i < ret; i++) { |
1332 | if (pages[i] == locked_page) { | |
1333 | page_cache_release(pages[i]); | |
1334 | continue; | |
1335 | } | |
1336 | if (clear_dirty) | |
1337 | clear_page_dirty_for_io(pages[i]); | |
1338 | if (set_writeback) | |
1339 | set_page_writeback(pages[i]); | |
1340 | if (end_writeback) | |
1341 | end_page_writeback(pages[i]); | |
771ed689 CM |
1342 | if (unlock_pages) |
1343 | unlock_page(pages[i]); | |
c8b97818 CM |
1344 | page_cache_release(pages[i]); |
1345 | } | |
1346 | nr_pages -= ret; | |
1347 | index += ret; | |
1348 | cond_resched(); | |
1349 | } | |
1350 | return 0; | |
1351 | } | |
c8b97818 | 1352 | |
d352ac68 CM |
1353 | /* |
1354 | * count the number of bytes in the tree that have a given bit(s) | |
1355 | * set. This can be fairly slow, except for EXTENT_DIRTY which is | |
1356 | * cached. The total number found is returned. | |
1357 | */ | |
d1310b2e CM |
1358 | u64 count_range_bits(struct extent_io_tree *tree, |
1359 | u64 *start, u64 search_end, u64 max_bytes, | |
1360 | unsigned long bits) | |
1361 | { | |
1362 | struct rb_node *node; | |
1363 | struct extent_state *state; | |
1364 | u64 cur_start = *start; | |
1365 | u64 total_bytes = 0; | |
1366 | int found = 0; | |
1367 | ||
1368 | if (search_end <= cur_start) { | |
d1310b2e CM |
1369 | WARN_ON(1); |
1370 | return 0; | |
1371 | } | |
1372 | ||
cad321ad | 1373 | spin_lock(&tree->lock); |
d1310b2e CM |
1374 | if (cur_start == 0 && bits == EXTENT_DIRTY) { |
1375 | total_bytes = tree->dirty_bytes; | |
1376 | goto out; | |
1377 | } | |
1378 | /* | |
1379 | * this search will find all the extents that end after | |
1380 | * our range starts. | |
1381 | */ | |
80ea96b1 | 1382 | node = tree_search(tree, cur_start); |
d397712b | 1383 | if (!node) |
d1310b2e | 1384 | goto out; |
d1310b2e | 1385 | |
d397712b | 1386 | while (1) { |
d1310b2e CM |
1387 | state = rb_entry(node, struct extent_state, rb_node); |
1388 | if (state->start > search_end) | |
1389 | break; | |
1390 | if (state->end >= cur_start && (state->state & bits)) { | |
1391 | total_bytes += min(search_end, state->end) + 1 - | |
1392 | max(cur_start, state->start); | |
1393 | if (total_bytes >= max_bytes) | |
1394 | break; | |
1395 | if (!found) { | |
1396 | *start = state->start; | |
1397 | found = 1; | |
1398 | } | |
1399 | } | |
1400 | node = rb_next(node); | |
1401 | if (!node) | |
1402 | break; | |
1403 | } | |
1404 | out: | |
cad321ad | 1405 | spin_unlock(&tree->lock); |
d1310b2e CM |
1406 | return total_bytes; |
1407 | } | |
b2950863 CH |
1408 | |
1409 | #if 0 | |
d1310b2e CM |
1410 | /* |
1411 | * helper function to lock both pages and extents in the tree. | |
1412 | * pages must be locked first. | |
1413 | */ | |
b2950863 | 1414 | static int lock_range(struct extent_io_tree *tree, u64 start, u64 end) |
d1310b2e CM |
1415 | { |
1416 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1417 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
1418 | struct page *page; | |
1419 | int err; | |
1420 | ||
1421 | while (index <= end_index) { | |
1422 | page = grab_cache_page(tree->mapping, index); | |
1423 | if (!page) { | |
1424 | err = -ENOMEM; | |
1425 | goto failed; | |
1426 | } | |
1427 | if (IS_ERR(page)) { | |
1428 | err = PTR_ERR(page); | |
1429 | goto failed; | |
1430 | } | |
1431 | index++; | |
1432 | } | |
1433 | lock_extent(tree, start, end, GFP_NOFS); | |
1434 | return 0; | |
1435 | ||
1436 | failed: | |
1437 | /* | |
1438 | * we failed above in getting the page at 'index', so we undo here | |
1439 | * up to but not including the page at 'index' | |
1440 | */ | |
1441 | end_index = index; | |
1442 | index = start >> PAGE_CACHE_SHIFT; | |
1443 | while (index < end_index) { | |
1444 | page = find_get_page(tree->mapping, index); | |
1445 | unlock_page(page); | |
1446 | page_cache_release(page); | |
1447 | index++; | |
1448 | } | |
1449 | return err; | |
1450 | } | |
d1310b2e CM |
1451 | |
1452 | /* | |
1453 | * helper function to unlock both pages and extents in the tree. | |
1454 | */ | |
b2950863 | 1455 | static int unlock_range(struct extent_io_tree *tree, u64 start, u64 end) |
d1310b2e CM |
1456 | { |
1457 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1458 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
1459 | struct page *page; | |
1460 | ||
1461 | while (index <= end_index) { | |
1462 | page = find_get_page(tree->mapping, index); | |
1463 | unlock_page(page); | |
1464 | page_cache_release(page); | |
1465 | index++; | |
1466 | } | |
1467 | unlock_extent(tree, start, end, GFP_NOFS); | |
1468 | return 0; | |
1469 | } | |
b2950863 | 1470 | #endif |
d1310b2e | 1471 | |
d352ac68 CM |
1472 | /* |
1473 | * set the private field for a given byte offset in the tree. If there isn't | |
1474 | * an extent_state there already, this does nothing. | |
1475 | */ | |
d1310b2e CM |
1476 | int set_state_private(struct extent_io_tree *tree, u64 start, u64 private) |
1477 | { | |
1478 | struct rb_node *node; | |
1479 | struct extent_state *state; | |
1480 | int ret = 0; | |
1481 | ||
cad321ad | 1482 | spin_lock(&tree->lock); |
d1310b2e CM |
1483 | /* |
1484 | * this search will find all the extents that end after | |
1485 | * our range starts. | |
1486 | */ | |
80ea96b1 | 1487 | node = tree_search(tree, start); |
2b114d1d | 1488 | if (!node) { |
d1310b2e CM |
1489 | ret = -ENOENT; |
1490 | goto out; | |
1491 | } | |
1492 | state = rb_entry(node, struct extent_state, rb_node); | |
1493 | if (state->start != start) { | |
1494 | ret = -ENOENT; | |
1495 | goto out; | |
1496 | } | |
1497 | state->private = private; | |
1498 | out: | |
cad321ad | 1499 | spin_unlock(&tree->lock); |
d1310b2e CM |
1500 | return ret; |
1501 | } | |
1502 | ||
1503 | int get_state_private(struct extent_io_tree *tree, u64 start, u64 *private) | |
1504 | { | |
1505 | struct rb_node *node; | |
1506 | struct extent_state *state; | |
1507 | int ret = 0; | |
1508 | ||
cad321ad | 1509 | spin_lock(&tree->lock); |
d1310b2e CM |
1510 | /* |
1511 | * this search will find all the extents that end after | |
1512 | * our range starts. | |
1513 | */ | |
80ea96b1 | 1514 | node = tree_search(tree, start); |
2b114d1d | 1515 | if (!node) { |
d1310b2e CM |
1516 | ret = -ENOENT; |
1517 | goto out; | |
1518 | } | |
1519 | state = rb_entry(node, struct extent_state, rb_node); | |
1520 | if (state->start != start) { | |
1521 | ret = -ENOENT; | |
1522 | goto out; | |
1523 | } | |
1524 | *private = state->private; | |
1525 | out: | |
cad321ad | 1526 | spin_unlock(&tree->lock); |
d1310b2e CM |
1527 | return ret; |
1528 | } | |
1529 | ||
1530 | /* | |
1531 | * searches a range in the state tree for a given mask. | |
70dec807 | 1532 | * If 'filled' == 1, this returns 1 only if every extent in the tree |
d1310b2e CM |
1533 | * has the bits set. Otherwise, 1 is returned if any bit in the |
1534 | * range is found set. | |
1535 | */ | |
1536 | int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end, | |
1537 | int bits, int filled) | |
1538 | { | |
1539 | struct extent_state *state = NULL; | |
1540 | struct rb_node *node; | |
1541 | int bitset = 0; | |
d1310b2e | 1542 | |
cad321ad | 1543 | spin_lock(&tree->lock); |
80ea96b1 | 1544 | node = tree_search(tree, start); |
d1310b2e CM |
1545 | while (node && start <= end) { |
1546 | state = rb_entry(node, struct extent_state, rb_node); | |
1547 | ||
1548 | if (filled && state->start > start) { | |
1549 | bitset = 0; | |
1550 | break; | |
1551 | } | |
1552 | ||
1553 | if (state->start > end) | |
1554 | break; | |
1555 | ||
1556 | if (state->state & bits) { | |
1557 | bitset = 1; | |
1558 | if (!filled) | |
1559 | break; | |
1560 | } else if (filled) { | |
1561 | bitset = 0; | |
1562 | break; | |
1563 | } | |
1564 | start = state->end + 1; | |
1565 | if (start > end) | |
1566 | break; | |
1567 | node = rb_next(node); | |
1568 | if (!node) { | |
1569 | if (filled) | |
1570 | bitset = 0; | |
1571 | break; | |
1572 | } | |
1573 | } | |
cad321ad | 1574 | spin_unlock(&tree->lock); |
d1310b2e CM |
1575 | return bitset; |
1576 | } | |
d1310b2e CM |
1577 | |
1578 | /* | |
1579 | * helper function to set a given page up to date if all the | |
1580 | * extents in the tree for that page are up to date | |
1581 | */ | |
1582 | static int check_page_uptodate(struct extent_io_tree *tree, | |
1583 | struct page *page) | |
1584 | { | |
1585 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
1586 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
1587 | if (test_range_bit(tree, start, end, EXTENT_UPTODATE, 1)) | |
1588 | SetPageUptodate(page); | |
1589 | return 0; | |
1590 | } | |
1591 | ||
1592 | /* | |
1593 | * helper function to unlock a page if all the extents in the tree | |
1594 | * for that page are unlocked | |
1595 | */ | |
1596 | static int check_page_locked(struct extent_io_tree *tree, | |
1597 | struct page *page) | |
1598 | { | |
1599 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
1600 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
1601 | if (!test_range_bit(tree, start, end, EXTENT_LOCKED, 0)) | |
1602 | unlock_page(page); | |
1603 | return 0; | |
1604 | } | |
1605 | ||
1606 | /* | |
1607 | * helper function to end page writeback if all the extents | |
1608 | * in the tree for that page are done with writeback | |
1609 | */ | |
1610 | static int check_page_writeback(struct extent_io_tree *tree, | |
1611 | struct page *page) | |
1612 | { | |
1613 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
1614 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
1615 | if (!test_range_bit(tree, start, end, EXTENT_WRITEBACK, 0)) | |
1616 | end_page_writeback(page); | |
1617 | return 0; | |
1618 | } | |
1619 | ||
1620 | /* lots and lots of room for performance fixes in the end_bio funcs */ | |
1621 | ||
1622 | /* | |
1623 | * after a writepage IO is done, we need to: | |
1624 | * clear the uptodate bits on error | |
1625 | * clear the writeback bits in the extent tree for this IO | |
1626 | * end_page_writeback if the page has no more pending IO | |
1627 | * | |
1628 | * Scheduling is not allowed, so the extent state tree is expected | |
1629 | * to have one and only one object corresponding to this IO. | |
1630 | */ | |
d1310b2e | 1631 | static void end_bio_extent_writepage(struct bio *bio, int err) |
d1310b2e | 1632 | { |
1259ab75 | 1633 | int uptodate = err == 0; |
d1310b2e | 1634 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; |
902b22f3 | 1635 | struct extent_io_tree *tree; |
d1310b2e CM |
1636 | u64 start; |
1637 | u64 end; | |
1638 | int whole_page; | |
1259ab75 | 1639 | int ret; |
d1310b2e | 1640 | |
d1310b2e CM |
1641 | do { |
1642 | struct page *page = bvec->bv_page; | |
902b22f3 DW |
1643 | tree = &BTRFS_I(page->mapping->host)->io_tree; |
1644 | ||
d1310b2e CM |
1645 | start = ((u64)page->index << PAGE_CACHE_SHIFT) + |
1646 | bvec->bv_offset; | |
1647 | end = start + bvec->bv_len - 1; | |
1648 | ||
1649 | if (bvec->bv_offset == 0 && bvec->bv_len == PAGE_CACHE_SIZE) | |
1650 | whole_page = 1; | |
1651 | else | |
1652 | whole_page = 0; | |
1653 | ||
1654 | if (--bvec >= bio->bi_io_vec) | |
1655 | prefetchw(&bvec->bv_page->flags); | |
1259ab75 CM |
1656 | if (tree->ops && tree->ops->writepage_end_io_hook) { |
1657 | ret = tree->ops->writepage_end_io_hook(page, start, | |
902b22f3 | 1658 | end, NULL, uptodate); |
1259ab75 CM |
1659 | if (ret) |
1660 | uptodate = 0; | |
1661 | } | |
1662 | ||
1663 | if (!uptodate && tree->ops && | |
1664 | tree->ops->writepage_io_failed_hook) { | |
1665 | ret = tree->ops->writepage_io_failed_hook(bio, page, | |
902b22f3 | 1666 | start, end, NULL); |
1259ab75 | 1667 | if (ret == 0) { |
1259ab75 CM |
1668 | uptodate = (err == 0); |
1669 | continue; | |
1670 | } | |
1671 | } | |
1672 | ||
d1310b2e CM |
1673 | if (!uptodate) { |
1674 | clear_extent_uptodate(tree, start, end, GFP_ATOMIC); | |
1675 | ClearPageUptodate(page); | |
1676 | SetPageError(page); | |
1677 | } | |
70dec807 | 1678 | |
902b22f3 | 1679 | clear_extent_writeback(tree, start, end, GFP_ATOMIC); |
d1310b2e CM |
1680 | |
1681 | if (whole_page) | |
1682 | end_page_writeback(page); | |
1683 | else | |
1684 | check_page_writeback(tree, page); | |
d1310b2e | 1685 | } while (bvec >= bio->bi_io_vec); |
2b1f55b0 | 1686 | |
d1310b2e | 1687 | bio_put(bio); |
d1310b2e CM |
1688 | } |
1689 | ||
1690 | /* | |
1691 | * after a readpage IO is done, we need to: | |
1692 | * clear the uptodate bits on error | |
1693 | * set the uptodate bits if things worked | |
1694 | * set the page up to date if all extents in the tree are uptodate | |
1695 | * clear the lock bit in the extent tree | |
1696 | * unlock the page if there are no other extents locked for it | |
1697 | * | |
1698 | * Scheduling is not allowed, so the extent state tree is expected | |
1699 | * to have one and only one object corresponding to this IO. | |
1700 | */ | |
d1310b2e | 1701 | static void end_bio_extent_readpage(struct bio *bio, int err) |
d1310b2e CM |
1702 | { |
1703 | int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); | |
1704 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; | |
902b22f3 | 1705 | struct extent_io_tree *tree; |
d1310b2e CM |
1706 | u64 start; |
1707 | u64 end; | |
1708 | int whole_page; | |
1709 | int ret; | |
1710 | ||
d20f7043 CM |
1711 | if (err) |
1712 | uptodate = 0; | |
1713 | ||
d1310b2e CM |
1714 | do { |
1715 | struct page *page = bvec->bv_page; | |
902b22f3 DW |
1716 | tree = &BTRFS_I(page->mapping->host)->io_tree; |
1717 | ||
d1310b2e CM |
1718 | start = ((u64)page->index << PAGE_CACHE_SHIFT) + |
1719 | bvec->bv_offset; | |
1720 | end = start + bvec->bv_len - 1; | |
1721 | ||
1722 | if (bvec->bv_offset == 0 && bvec->bv_len == PAGE_CACHE_SIZE) | |
1723 | whole_page = 1; | |
1724 | else | |
1725 | whole_page = 0; | |
1726 | ||
1727 | if (--bvec >= bio->bi_io_vec) | |
1728 | prefetchw(&bvec->bv_page->flags); | |
1729 | ||
1730 | if (uptodate && tree->ops && tree->ops->readpage_end_io_hook) { | |
70dec807 | 1731 | ret = tree->ops->readpage_end_io_hook(page, start, end, |
902b22f3 | 1732 | NULL); |
d1310b2e CM |
1733 | if (ret) |
1734 | uptodate = 0; | |
1735 | } | |
7e38326f CM |
1736 | if (!uptodate && tree->ops && |
1737 | tree->ops->readpage_io_failed_hook) { | |
1738 | ret = tree->ops->readpage_io_failed_hook(bio, page, | |
902b22f3 | 1739 | start, end, NULL); |
7e38326f | 1740 | if (ret == 0) { |
3b951516 CM |
1741 | uptodate = |
1742 | test_bit(BIO_UPTODATE, &bio->bi_flags); | |
d20f7043 CM |
1743 | if (err) |
1744 | uptodate = 0; | |
7e38326f CM |
1745 | continue; |
1746 | } | |
1747 | } | |
d1310b2e | 1748 | |
771ed689 | 1749 | if (uptodate) { |
902b22f3 DW |
1750 | set_extent_uptodate(tree, start, end, |
1751 | GFP_ATOMIC); | |
771ed689 | 1752 | } |
902b22f3 | 1753 | unlock_extent(tree, start, end, GFP_ATOMIC); |
d1310b2e | 1754 | |
70dec807 CM |
1755 | if (whole_page) { |
1756 | if (uptodate) { | |
1757 | SetPageUptodate(page); | |
1758 | } else { | |
1759 | ClearPageUptodate(page); | |
1760 | SetPageError(page); | |
1761 | } | |
d1310b2e | 1762 | unlock_page(page); |
70dec807 CM |
1763 | } else { |
1764 | if (uptodate) { | |
1765 | check_page_uptodate(tree, page); | |
1766 | } else { | |
1767 | ClearPageUptodate(page); | |
1768 | SetPageError(page); | |
1769 | } | |
d1310b2e | 1770 | check_page_locked(tree, page); |
70dec807 | 1771 | } |
d1310b2e CM |
1772 | } while (bvec >= bio->bi_io_vec); |
1773 | ||
1774 | bio_put(bio); | |
d1310b2e CM |
1775 | } |
1776 | ||
1777 | /* | |
1778 | * IO done from prepare_write is pretty simple, we just unlock | |
1779 | * the structs in the extent tree when done, and set the uptodate bits | |
1780 | * as appropriate. | |
1781 | */ | |
d1310b2e | 1782 | static void end_bio_extent_preparewrite(struct bio *bio, int err) |
d1310b2e CM |
1783 | { |
1784 | const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); | |
1785 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; | |
902b22f3 | 1786 | struct extent_io_tree *tree; |
d1310b2e CM |
1787 | u64 start; |
1788 | u64 end; | |
1789 | ||
d1310b2e CM |
1790 | do { |
1791 | struct page *page = bvec->bv_page; | |
902b22f3 DW |
1792 | tree = &BTRFS_I(page->mapping->host)->io_tree; |
1793 | ||
d1310b2e CM |
1794 | start = ((u64)page->index << PAGE_CACHE_SHIFT) + |
1795 | bvec->bv_offset; | |
1796 | end = start + bvec->bv_len - 1; | |
1797 | ||
1798 | if (--bvec >= bio->bi_io_vec) | |
1799 | prefetchw(&bvec->bv_page->flags); | |
1800 | ||
1801 | if (uptodate) { | |
1802 | set_extent_uptodate(tree, start, end, GFP_ATOMIC); | |
1803 | } else { | |
1804 | ClearPageUptodate(page); | |
1805 | SetPageError(page); | |
1806 | } | |
1807 | ||
1808 | unlock_extent(tree, start, end, GFP_ATOMIC); | |
1809 | ||
1810 | } while (bvec >= bio->bi_io_vec); | |
1811 | ||
1812 | bio_put(bio); | |
d1310b2e CM |
1813 | } |
1814 | ||
1815 | static struct bio * | |
1816 | extent_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs, | |
1817 | gfp_t gfp_flags) | |
1818 | { | |
1819 | struct bio *bio; | |
1820 | ||
1821 | bio = bio_alloc(gfp_flags, nr_vecs); | |
1822 | ||
1823 | if (bio == NULL && (current->flags & PF_MEMALLOC)) { | |
1824 | while (!bio && (nr_vecs /= 2)) | |
1825 | bio = bio_alloc(gfp_flags, nr_vecs); | |
1826 | } | |
1827 | ||
1828 | if (bio) { | |
e1c4b745 | 1829 | bio->bi_size = 0; |
d1310b2e CM |
1830 | bio->bi_bdev = bdev; |
1831 | bio->bi_sector = first_sector; | |
1832 | } | |
1833 | return bio; | |
1834 | } | |
1835 | ||
c8b97818 CM |
1836 | static int submit_one_bio(int rw, struct bio *bio, int mirror_num, |
1837 | unsigned long bio_flags) | |
d1310b2e | 1838 | { |
d1310b2e | 1839 | int ret = 0; |
70dec807 CM |
1840 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; |
1841 | struct page *page = bvec->bv_page; | |
1842 | struct extent_io_tree *tree = bio->bi_private; | |
70dec807 CM |
1843 | u64 start; |
1844 | u64 end; | |
1845 | ||
1846 | start = ((u64)page->index << PAGE_CACHE_SHIFT) + bvec->bv_offset; | |
1847 | end = start + bvec->bv_len - 1; | |
1848 | ||
902b22f3 | 1849 | bio->bi_private = NULL; |
d1310b2e CM |
1850 | |
1851 | bio_get(bio); | |
1852 | ||
065631f6 | 1853 | if (tree->ops && tree->ops->submit_bio_hook) |
f188591e | 1854 | tree->ops->submit_bio_hook(page->mapping->host, rw, bio, |
c8b97818 | 1855 | mirror_num, bio_flags); |
0b86a832 CM |
1856 | else |
1857 | submit_bio(rw, bio); | |
d1310b2e CM |
1858 | if (bio_flagged(bio, BIO_EOPNOTSUPP)) |
1859 | ret = -EOPNOTSUPP; | |
1860 | bio_put(bio); | |
1861 | return ret; | |
1862 | } | |
1863 | ||
1864 | static int submit_extent_page(int rw, struct extent_io_tree *tree, | |
1865 | struct page *page, sector_t sector, | |
1866 | size_t size, unsigned long offset, | |
1867 | struct block_device *bdev, | |
1868 | struct bio **bio_ret, | |
1869 | unsigned long max_pages, | |
f188591e | 1870 | bio_end_io_t end_io_func, |
c8b97818 CM |
1871 | int mirror_num, |
1872 | unsigned long prev_bio_flags, | |
1873 | unsigned long bio_flags) | |
d1310b2e CM |
1874 | { |
1875 | int ret = 0; | |
1876 | struct bio *bio; | |
1877 | int nr; | |
c8b97818 CM |
1878 | int contig = 0; |
1879 | int this_compressed = bio_flags & EXTENT_BIO_COMPRESSED; | |
1880 | int old_compressed = prev_bio_flags & EXTENT_BIO_COMPRESSED; | |
5b050f04 | 1881 | size_t page_size = min_t(size_t, size, PAGE_CACHE_SIZE); |
d1310b2e CM |
1882 | |
1883 | if (bio_ret && *bio_ret) { | |
1884 | bio = *bio_ret; | |
c8b97818 CM |
1885 | if (old_compressed) |
1886 | contig = bio->bi_sector == sector; | |
1887 | else | |
1888 | contig = bio->bi_sector + (bio->bi_size >> 9) == | |
1889 | sector; | |
1890 | ||
1891 | if (prev_bio_flags != bio_flags || !contig || | |
239b14b3 | 1892 | (tree->ops && tree->ops->merge_bio_hook && |
c8b97818 CM |
1893 | tree->ops->merge_bio_hook(page, offset, page_size, bio, |
1894 | bio_flags)) || | |
1895 | bio_add_page(bio, page, page_size, offset) < page_size) { | |
1896 | ret = submit_one_bio(rw, bio, mirror_num, | |
1897 | prev_bio_flags); | |
d1310b2e CM |
1898 | bio = NULL; |
1899 | } else { | |
1900 | return 0; | |
1901 | } | |
1902 | } | |
c8b97818 CM |
1903 | if (this_compressed) |
1904 | nr = BIO_MAX_PAGES; | |
1905 | else | |
1906 | nr = bio_get_nr_vecs(bdev); | |
1907 | ||
d1310b2e | 1908 | bio = extent_bio_alloc(bdev, sector, nr, GFP_NOFS | __GFP_HIGH); |
70dec807 | 1909 | |
c8b97818 | 1910 | bio_add_page(bio, page, page_size, offset); |
d1310b2e CM |
1911 | bio->bi_end_io = end_io_func; |
1912 | bio->bi_private = tree; | |
70dec807 | 1913 | |
d397712b | 1914 | if (bio_ret) |
d1310b2e | 1915 | *bio_ret = bio; |
d397712b | 1916 | else |
c8b97818 | 1917 | ret = submit_one_bio(rw, bio, mirror_num, bio_flags); |
d1310b2e CM |
1918 | |
1919 | return ret; | |
1920 | } | |
1921 | ||
1922 | void set_page_extent_mapped(struct page *page) | |
1923 | { | |
1924 | if (!PagePrivate(page)) { | |
1925 | SetPagePrivate(page); | |
d1310b2e | 1926 | page_cache_get(page); |
6af118ce | 1927 | set_page_private(page, EXTENT_PAGE_PRIVATE); |
d1310b2e CM |
1928 | } |
1929 | } | |
1930 | ||
b2950863 | 1931 | static void set_page_extent_head(struct page *page, unsigned long len) |
d1310b2e CM |
1932 | { |
1933 | set_page_private(page, EXTENT_PAGE_PRIVATE_FIRST_PAGE | len << 2); | |
1934 | } | |
1935 | ||
1936 | /* | |
1937 | * basic readpage implementation. Locked extent state structs are inserted | |
1938 | * into the tree that are removed when the IO is done (by the end_io | |
1939 | * handlers) | |
1940 | */ | |
1941 | static int __extent_read_full_page(struct extent_io_tree *tree, | |
1942 | struct page *page, | |
1943 | get_extent_t *get_extent, | |
c8b97818 CM |
1944 | struct bio **bio, int mirror_num, |
1945 | unsigned long *bio_flags) | |
d1310b2e CM |
1946 | { |
1947 | struct inode *inode = page->mapping->host; | |
1948 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
1949 | u64 page_end = start + PAGE_CACHE_SIZE - 1; | |
1950 | u64 end; | |
1951 | u64 cur = start; | |
1952 | u64 extent_offset; | |
1953 | u64 last_byte = i_size_read(inode); | |
1954 | u64 block_start; | |
1955 | u64 cur_end; | |
1956 | sector_t sector; | |
1957 | struct extent_map *em; | |
1958 | struct block_device *bdev; | |
1959 | int ret; | |
1960 | int nr = 0; | |
1961 | size_t page_offset = 0; | |
1962 | size_t iosize; | |
c8b97818 | 1963 | size_t disk_io_size; |
d1310b2e | 1964 | size_t blocksize = inode->i_sb->s_blocksize; |
c8b97818 | 1965 | unsigned long this_bio_flag = 0; |
d1310b2e CM |
1966 | |
1967 | set_page_extent_mapped(page); | |
1968 | ||
1969 | end = page_end; | |
1970 | lock_extent(tree, start, end, GFP_NOFS); | |
1971 | ||
c8b97818 CM |
1972 | if (page->index == last_byte >> PAGE_CACHE_SHIFT) { |
1973 | char *userpage; | |
1974 | size_t zero_offset = last_byte & (PAGE_CACHE_SIZE - 1); | |
1975 | ||
1976 | if (zero_offset) { | |
1977 | iosize = PAGE_CACHE_SIZE - zero_offset; | |
1978 | userpage = kmap_atomic(page, KM_USER0); | |
1979 | memset(userpage + zero_offset, 0, iosize); | |
1980 | flush_dcache_page(page); | |
1981 | kunmap_atomic(userpage, KM_USER0); | |
1982 | } | |
1983 | } | |
d1310b2e CM |
1984 | while (cur <= end) { |
1985 | if (cur >= last_byte) { | |
1986 | char *userpage; | |
1987 | iosize = PAGE_CACHE_SIZE - page_offset; | |
1988 | userpage = kmap_atomic(page, KM_USER0); | |
1989 | memset(userpage + page_offset, 0, iosize); | |
1990 | flush_dcache_page(page); | |
1991 | kunmap_atomic(userpage, KM_USER0); | |
1992 | set_extent_uptodate(tree, cur, cur + iosize - 1, | |
1993 | GFP_NOFS); | |
1994 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); | |
1995 | break; | |
1996 | } | |
1997 | em = get_extent(inode, page, page_offset, cur, | |
1998 | end - cur + 1, 0); | |
1999 | if (IS_ERR(em) || !em) { | |
2000 | SetPageError(page); | |
2001 | unlock_extent(tree, cur, end, GFP_NOFS); | |
2002 | break; | |
2003 | } | |
d1310b2e CM |
2004 | extent_offset = cur - em->start; |
2005 | BUG_ON(extent_map_end(em) <= cur); | |
2006 | BUG_ON(end < cur); | |
2007 | ||
c8b97818 CM |
2008 | if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) |
2009 | this_bio_flag = EXTENT_BIO_COMPRESSED; | |
2010 | ||
d1310b2e CM |
2011 | iosize = min(extent_map_end(em) - cur, end - cur + 1); |
2012 | cur_end = min(extent_map_end(em) - 1, end); | |
2013 | iosize = (iosize + blocksize - 1) & ~((u64)blocksize - 1); | |
c8b97818 CM |
2014 | if (this_bio_flag & EXTENT_BIO_COMPRESSED) { |
2015 | disk_io_size = em->block_len; | |
2016 | sector = em->block_start >> 9; | |
2017 | } else { | |
2018 | sector = (em->block_start + extent_offset) >> 9; | |
2019 | disk_io_size = iosize; | |
2020 | } | |
d1310b2e CM |
2021 | bdev = em->bdev; |
2022 | block_start = em->block_start; | |
d899e052 YZ |
2023 | if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) |
2024 | block_start = EXTENT_MAP_HOLE; | |
d1310b2e CM |
2025 | free_extent_map(em); |
2026 | em = NULL; | |
2027 | ||
2028 | /* we've found a hole, just zero and go on */ | |
2029 | if (block_start == EXTENT_MAP_HOLE) { | |
2030 | char *userpage; | |
2031 | userpage = kmap_atomic(page, KM_USER0); | |
2032 | memset(userpage + page_offset, 0, iosize); | |
2033 | flush_dcache_page(page); | |
2034 | kunmap_atomic(userpage, KM_USER0); | |
2035 | ||
2036 | set_extent_uptodate(tree, cur, cur + iosize - 1, | |
2037 | GFP_NOFS); | |
2038 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); | |
2039 | cur = cur + iosize; | |
2040 | page_offset += iosize; | |
2041 | continue; | |
2042 | } | |
2043 | /* the get_extent function already copied into the page */ | |
2044 | if (test_range_bit(tree, cur, cur_end, EXTENT_UPTODATE, 1)) { | |
a1b32a59 | 2045 | check_page_uptodate(tree, page); |
d1310b2e CM |
2046 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); |
2047 | cur = cur + iosize; | |
2048 | page_offset += iosize; | |
2049 | continue; | |
2050 | } | |
70dec807 CM |
2051 | /* we have an inline extent but it didn't get marked up |
2052 | * to date. Error out | |
2053 | */ | |
2054 | if (block_start == EXTENT_MAP_INLINE) { | |
2055 | SetPageError(page); | |
2056 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); | |
2057 | cur = cur + iosize; | |
2058 | page_offset += iosize; | |
2059 | continue; | |
2060 | } | |
d1310b2e CM |
2061 | |
2062 | ret = 0; | |
2063 | if (tree->ops && tree->ops->readpage_io_hook) { | |
2064 | ret = tree->ops->readpage_io_hook(page, cur, | |
2065 | cur + iosize - 1); | |
2066 | } | |
2067 | if (!ret) { | |
89642229 CM |
2068 | unsigned long pnr = (last_byte >> PAGE_CACHE_SHIFT) + 1; |
2069 | pnr -= page->index; | |
d1310b2e | 2070 | ret = submit_extent_page(READ, tree, page, |
c8b97818 | 2071 | sector, disk_io_size, page_offset, |
89642229 | 2072 | bdev, bio, pnr, |
c8b97818 CM |
2073 | end_bio_extent_readpage, mirror_num, |
2074 | *bio_flags, | |
2075 | this_bio_flag); | |
89642229 | 2076 | nr++; |
c8b97818 | 2077 | *bio_flags = this_bio_flag; |
d1310b2e CM |
2078 | } |
2079 | if (ret) | |
2080 | SetPageError(page); | |
2081 | cur = cur + iosize; | |
2082 | page_offset += iosize; | |
d1310b2e CM |
2083 | } |
2084 | if (!nr) { | |
2085 | if (!PageError(page)) | |
2086 | SetPageUptodate(page); | |
2087 | unlock_page(page); | |
2088 | } | |
2089 | return 0; | |
2090 | } | |
2091 | ||
2092 | int extent_read_full_page(struct extent_io_tree *tree, struct page *page, | |
2093 | get_extent_t *get_extent) | |
2094 | { | |
2095 | struct bio *bio = NULL; | |
c8b97818 | 2096 | unsigned long bio_flags = 0; |
d1310b2e CM |
2097 | int ret; |
2098 | ||
c8b97818 CM |
2099 | ret = __extent_read_full_page(tree, page, get_extent, &bio, 0, |
2100 | &bio_flags); | |
d1310b2e | 2101 | if (bio) |
c8b97818 | 2102 | submit_one_bio(READ, bio, 0, bio_flags); |
d1310b2e CM |
2103 | return ret; |
2104 | } | |
d1310b2e CM |
2105 | |
2106 | /* | |
2107 | * the writepage semantics are similar to regular writepage. extent | |
2108 | * records are inserted to lock ranges in the tree, and as dirty areas | |
2109 | * are found, they are marked writeback. Then the lock bits are removed | |
2110 | * and the end_io handler clears the writeback ranges | |
2111 | */ | |
2112 | static int __extent_writepage(struct page *page, struct writeback_control *wbc, | |
2113 | void *data) | |
2114 | { | |
2115 | struct inode *inode = page->mapping->host; | |
2116 | struct extent_page_data *epd = data; | |
2117 | struct extent_io_tree *tree = epd->tree; | |
2118 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
2119 | u64 delalloc_start; | |
2120 | u64 page_end = start + PAGE_CACHE_SIZE - 1; | |
2121 | u64 end; | |
2122 | u64 cur = start; | |
2123 | u64 extent_offset; | |
2124 | u64 last_byte = i_size_read(inode); | |
2125 | u64 block_start; | |
2126 | u64 iosize; | |
e6dcd2dc | 2127 | u64 unlock_start; |
d1310b2e CM |
2128 | sector_t sector; |
2129 | struct extent_map *em; | |
2130 | struct block_device *bdev; | |
2131 | int ret; | |
2132 | int nr = 0; | |
7f3c74fb | 2133 | size_t pg_offset = 0; |
d1310b2e CM |
2134 | size_t blocksize; |
2135 | loff_t i_size = i_size_read(inode); | |
2136 | unsigned long end_index = i_size >> PAGE_CACHE_SHIFT; | |
2137 | u64 nr_delalloc; | |
2138 | u64 delalloc_end; | |
c8b97818 CM |
2139 | int page_started; |
2140 | int compressed; | |
771ed689 | 2141 | unsigned long nr_written = 0; |
d1310b2e CM |
2142 | |
2143 | WARN_ON(!PageLocked(page)); | |
7f3c74fb | 2144 | pg_offset = i_size & (PAGE_CACHE_SIZE - 1); |
211c17f5 | 2145 | if (page->index > end_index || |
7f3c74fb | 2146 | (page->index == end_index && !pg_offset)) { |
39be25cd | 2147 | page->mapping->a_ops->invalidatepage(page, 0); |
d1310b2e CM |
2148 | unlock_page(page); |
2149 | return 0; | |
2150 | } | |
2151 | ||
2152 | if (page->index == end_index) { | |
2153 | char *userpage; | |
2154 | ||
d1310b2e | 2155 | userpage = kmap_atomic(page, KM_USER0); |
7f3c74fb CM |
2156 | memset(userpage + pg_offset, 0, |
2157 | PAGE_CACHE_SIZE - pg_offset); | |
d1310b2e | 2158 | kunmap_atomic(userpage, KM_USER0); |
211c17f5 | 2159 | flush_dcache_page(page); |
d1310b2e | 2160 | } |
7f3c74fb | 2161 | pg_offset = 0; |
d1310b2e CM |
2162 | |
2163 | set_page_extent_mapped(page); | |
2164 | ||
2165 | delalloc_start = start; | |
2166 | delalloc_end = 0; | |
c8b97818 | 2167 | page_started = 0; |
771ed689 | 2168 | if (!epd->extent_locked) { |
d397712b | 2169 | while (delalloc_end < page_end) { |
771ed689 | 2170 | nr_delalloc = find_lock_delalloc_range(inode, tree, |
c8b97818 CM |
2171 | page, |
2172 | &delalloc_start, | |
d1310b2e CM |
2173 | &delalloc_end, |
2174 | 128 * 1024 * 1024); | |
771ed689 CM |
2175 | if (nr_delalloc == 0) { |
2176 | delalloc_start = delalloc_end + 1; | |
2177 | continue; | |
2178 | } | |
2179 | tree->ops->fill_delalloc(inode, page, delalloc_start, | |
2180 | delalloc_end, &page_started, | |
2181 | &nr_written); | |
d1310b2e | 2182 | delalloc_start = delalloc_end + 1; |
d1310b2e | 2183 | } |
c8b97818 | 2184 | |
771ed689 CM |
2185 | /* did the fill delalloc function already unlock and start |
2186 | * the IO? | |
2187 | */ | |
2188 | if (page_started) { | |
2189 | ret = 0; | |
2190 | goto update_nr_written; | |
2191 | } | |
c8b97818 | 2192 | } |
d1310b2e | 2193 | lock_extent(tree, start, page_end, GFP_NOFS); |
771ed689 | 2194 | |
e6dcd2dc | 2195 | unlock_start = start; |
d1310b2e | 2196 | |
247e743c | 2197 | if (tree->ops && tree->ops->writepage_start_hook) { |
c8b97818 CM |
2198 | ret = tree->ops->writepage_start_hook(page, start, |
2199 | page_end); | |
247e743c CM |
2200 | if (ret == -EAGAIN) { |
2201 | unlock_extent(tree, start, page_end, GFP_NOFS); | |
2202 | redirty_page_for_writepage(wbc, page); | |
2203 | unlock_page(page); | |
771ed689 CM |
2204 | ret = 0; |
2205 | goto update_nr_written; | |
247e743c CM |
2206 | } |
2207 | } | |
2208 | ||
771ed689 CM |
2209 | nr_written++; |
2210 | ||
d1310b2e | 2211 | end = page_end; |
d397712b CM |
2212 | if (test_range_bit(tree, start, page_end, EXTENT_DELALLOC, 0)) |
2213 | printk(KERN_ERR "btrfs delalloc bits after lock_extent\n"); | |
d1310b2e CM |
2214 | |
2215 | if (last_byte <= start) { | |
2216 | clear_extent_dirty(tree, start, page_end, GFP_NOFS); | |
e6dcd2dc CM |
2217 | unlock_extent(tree, start, page_end, GFP_NOFS); |
2218 | if (tree->ops && tree->ops->writepage_end_io_hook) | |
2219 | tree->ops->writepage_end_io_hook(page, start, | |
2220 | page_end, NULL, 1); | |
2221 | unlock_start = page_end + 1; | |
d1310b2e CM |
2222 | goto done; |
2223 | } | |
2224 | ||
2225 | set_extent_uptodate(tree, start, page_end, GFP_NOFS); | |
2226 | blocksize = inode->i_sb->s_blocksize; | |
2227 | ||
2228 | while (cur <= end) { | |
2229 | if (cur >= last_byte) { | |
2230 | clear_extent_dirty(tree, cur, page_end, GFP_NOFS); | |
e6dcd2dc CM |
2231 | unlock_extent(tree, unlock_start, page_end, GFP_NOFS); |
2232 | if (tree->ops && tree->ops->writepage_end_io_hook) | |
2233 | tree->ops->writepage_end_io_hook(page, cur, | |
2234 | page_end, NULL, 1); | |
2235 | unlock_start = page_end + 1; | |
d1310b2e CM |
2236 | break; |
2237 | } | |
7f3c74fb | 2238 | em = epd->get_extent(inode, page, pg_offset, cur, |
d1310b2e CM |
2239 | end - cur + 1, 1); |
2240 | if (IS_ERR(em) || !em) { | |
2241 | SetPageError(page); | |
2242 | break; | |
2243 | } | |
2244 | ||
2245 | extent_offset = cur - em->start; | |
2246 | BUG_ON(extent_map_end(em) <= cur); | |
2247 | BUG_ON(end < cur); | |
2248 | iosize = min(extent_map_end(em) - cur, end - cur + 1); | |
2249 | iosize = (iosize + blocksize - 1) & ~((u64)blocksize - 1); | |
2250 | sector = (em->block_start + extent_offset) >> 9; | |
2251 | bdev = em->bdev; | |
2252 | block_start = em->block_start; | |
c8b97818 | 2253 | compressed = test_bit(EXTENT_FLAG_COMPRESSED, &em->flags); |
d1310b2e CM |
2254 | free_extent_map(em); |
2255 | em = NULL; | |
2256 | ||
c8b97818 CM |
2257 | /* |
2258 | * compressed and inline extents are written through other | |
2259 | * paths in the FS | |
2260 | */ | |
2261 | if (compressed || block_start == EXTENT_MAP_HOLE || | |
d1310b2e CM |
2262 | block_start == EXTENT_MAP_INLINE) { |
2263 | clear_extent_dirty(tree, cur, | |
2264 | cur + iosize - 1, GFP_NOFS); | |
e6dcd2dc | 2265 | |
d397712b | 2266 | unlock_extent(tree, unlock_start, cur + iosize - 1, |
e6dcd2dc | 2267 | GFP_NOFS); |
7f3c74fb | 2268 | |
c8b97818 CM |
2269 | /* |
2270 | * end_io notification does not happen here for | |
2271 | * compressed extents | |
2272 | */ | |
2273 | if (!compressed && tree->ops && | |
2274 | tree->ops->writepage_end_io_hook) | |
e6dcd2dc CM |
2275 | tree->ops->writepage_end_io_hook(page, cur, |
2276 | cur + iosize - 1, | |
2277 | NULL, 1); | |
c8b97818 CM |
2278 | else if (compressed) { |
2279 | /* we don't want to end_page_writeback on | |
2280 | * a compressed extent. this happens | |
2281 | * elsewhere | |
2282 | */ | |
2283 | nr++; | |
2284 | } | |
2285 | ||
2286 | cur += iosize; | |
7f3c74fb | 2287 | pg_offset += iosize; |
e6dcd2dc | 2288 | unlock_start = cur; |
d1310b2e CM |
2289 | continue; |
2290 | } | |
d1310b2e CM |
2291 | /* leave this out until we have a page_mkwrite call */ |
2292 | if (0 && !test_range_bit(tree, cur, cur + iosize - 1, | |
2293 | EXTENT_DIRTY, 0)) { | |
2294 | cur = cur + iosize; | |
7f3c74fb | 2295 | pg_offset += iosize; |
d1310b2e CM |
2296 | continue; |
2297 | } | |
c8b97818 | 2298 | |
d1310b2e CM |
2299 | clear_extent_dirty(tree, cur, cur + iosize - 1, GFP_NOFS); |
2300 | if (tree->ops && tree->ops->writepage_io_hook) { | |
2301 | ret = tree->ops->writepage_io_hook(page, cur, | |
2302 | cur + iosize - 1); | |
2303 | } else { | |
2304 | ret = 0; | |
2305 | } | |
1259ab75 | 2306 | if (ret) { |
d1310b2e | 2307 | SetPageError(page); |
1259ab75 | 2308 | } else { |
d1310b2e | 2309 | unsigned long max_nr = end_index + 1; |
7f3c74fb | 2310 | |
d1310b2e CM |
2311 | set_range_writeback(tree, cur, cur + iosize - 1); |
2312 | if (!PageWriteback(page)) { | |
d397712b CM |
2313 | printk(KERN_ERR "btrfs warning page %lu not " |
2314 | "writeback, cur %llu end %llu\n", | |
2315 | page->index, (unsigned long long)cur, | |
d1310b2e CM |
2316 | (unsigned long long)end); |
2317 | } | |
2318 | ||
2319 | ret = submit_extent_page(WRITE, tree, page, sector, | |
7f3c74fb | 2320 | iosize, pg_offset, bdev, |
d1310b2e | 2321 | &epd->bio, max_nr, |
c8b97818 CM |
2322 | end_bio_extent_writepage, |
2323 | 0, 0, 0); | |
d1310b2e CM |
2324 | if (ret) |
2325 | SetPageError(page); | |
2326 | } | |
2327 | cur = cur + iosize; | |
7f3c74fb | 2328 | pg_offset += iosize; |
d1310b2e CM |
2329 | nr++; |
2330 | } | |
2331 | done: | |
2332 | if (nr == 0) { | |
2333 | /* make sure the mapping tag for page dirty gets cleared */ | |
2334 | set_page_writeback(page); | |
2335 | end_page_writeback(page); | |
2336 | } | |
e6dcd2dc CM |
2337 | if (unlock_start <= page_end) |
2338 | unlock_extent(tree, unlock_start, page_end, GFP_NOFS); | |
d1310b2e | 2339 | unlock_page(page); |
771ed689 CM |
2340 | |
2341 | update_nr_written: | |
2342 | wbc->nr_to_write -= nr_written; | |
2343 | if (wbc->range_cyclic || (wbc->nr_to_write > 0 && | |
2344 | wbc->range_start == 0 && wbc->range_end == LLONG_MAX)) | |
2345 | page->mapping->writeback_index = page->index + nr_written; | |
d1310b2e CM |
2346 | return 0; |
2347 | } | |
2348 | ||
d1310b2e | 2349 | /** |
4bef0848 | 2350 | * write_cache_pages - walk the list of dirty pages of the given address space and write all of them. |
d1310b2e CM |
2351 | * @mapping: address space structure to write |
2352 | * @wbc: subtract the number of written pages from *@wbc->nr_to_write | |
2353 | * @writepage: function called for each page | |
2354 | * @data: data passed to writepage function | |
2355 | * | |
2356 | * If a page is already under I/O, write_cache_pages() skips it, even | |
2357 | * if it's dirty. This is desirable behaviour for memory-cleaning writeback, | |
2358 | * but it is INCORRECT for data-integrity system calls such as fsync(). fsync() | |
2359 | * and msync() need to guarantee that all the data which was dirty at the time | |
2360 | * the call was made get new I/O started against them. If wbc->sync_mode is | |
2361 | * WB_SYNC_ALL then we were called for data integrity and we must wait for | |
2362 | * existing IO to complete. | |
2363 | */ | |
b2950863 | 2364 | static int extent_write_cache_pages(struct extent_io_tree *tree, |
4bef0848 CM |
2365 | struct address_space *mapping, |
2366 | struct writeback_control *wbc, | |
d2c3f4f6 CM |
2367 | writepage_t writepage, void *data, |
2368 | void (*flush_fn)(void *)) | |
d1310b2e CM |
2369 | { |
2370 | struct backing_dev_info *bdi = mapping->backing_dev_info; | |
2371 | int ret = 0; | |
2372 | int done = 0; | |
2373 | struct pagevec pvec; | |
2374 | int nr_pages; | |
2375 | pgoff_t index; | |
2376 | pgoff_t end; /* Inclusive */ | |
2377 | int scanned = 0; | |
2378 | int range_whole = 0; | |
2379 | ||
2380 | if (wbc->nonblocking && bdi_write_congested(bdi)) { | |
2381 | wbc->encountered_congestion = 1; | |
2382 | return 0; | |
2383 | } | |
2384 | ||
2385 | pagevec_init(&pvec, 0); | |
2386 | if (wbc->range_cyclic) { | |
2387 | index = mapping->writeback_index; /* Start from prev offset */ | |
2388 | end = -1; | |
2389 | } else { | |
2390 | index = wbc->range_start >> PAGE_CACHE_SHIFT; | |
2391 | end = wbc->range_end >> PAGE_CACHE_SHIFT; | |
2392 | if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) | |
2393 | range_whole = 1; | |
2394 | scanned = 1; | |
2395 | } | |
2396 | retry: | |
2397 | while (!done && (index <= end) && | |
2398 | (nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, | |
d397712b CM |
2399 | PAGECACHE_TAG_DIRTY, min(end - index, |
2400 | (pgoff_t)PAGEVEC_SIZE-1) + 1))) { | |
d1310b2e CM |
2401 | unsigned i; |
2402 | ||
2403 | scanned = 1; | |
2404 | for (i = 0; i < nr_pages; i++) { | |
2405 | struct page *page = pvec.pages[i]; | |
2406 | ||
2407 | /* | |
2408 | * At this point we hold neither mapping->tree_lock nor | |
2409 | * lock on the page itself: the page may be truncated or | |
2410 | * invalidated (changing page->mapping to NULL), or even | |
2411 | * swizzled back from swapper_space to tmpfs file | |
2412 | * mapping | |
2413 | */ | |
4bef0848 CM |
2414 | if (tree->ops && tree->ops->write_cache_pages_lock_hook) |
2415 | tree->ops->write_cache_pages_lock_hook(page); | |
2416 | else | |
2417 | lock_page(page); | |
d1310b2e CM |
2418 | |
2419 | if (unlikely(page->mapping != mapping)) { | |
2420 | unlock_page(page); | |
2421 | continue; | |
2422 | } | |
2423 | ||
2424 | if (!wbc->range_cyclic && page->index > end) { | |
2425 | done = 1; | |
2426 | unlock_page(page); | |
2427 | continue; | |
2428 | } | |
2429 | ||
d2c3f4f6 | 2430 | if (wbc->sync_mode != WB_SYNC_NONE) { |
0e6bd956 CM |
2431 | if (PageWriteback(page)) |
2432 | flush_fn(data); | |
d1310b2e | 2433 | wait_on_page_writeback(page); |
d2c3f4f6 | 2434 | } |
d1310b2e CM |
2435 | |
2436 | if (PageWriteback(page) || | |
2437 | !clear_page_dirty_for_io(page)) { | |
2438 | unlock_page(page); | |
2439 | continue; | |
2440 | } | |
2441 | ||
2442 | ret = (*writepage)(page, wbc, data); | |
2443 | ||
2444 | if (unlikely(ret == AOP_WRITEPAGE_ACTIVATE)) { | |
2445 | unlock_page(page); | |
2446 | ret = 0; | |
2447 | } | |
771ed689 | 2448 | if (ret || wbc->nr_to_write <= 0) |
d1310b2e CM |
2449 | done = 1; |
2450 | if (wbc->nonblocking && bdi_write_congested(bdi)) { | |
2451 | wbc->encountered_congestion = 1; | |
2452 | done = 1; | |
2453 | } | |
2454 | } | |
2455 | pagevec_release(&pvec); | |
2456 | cond_resched(); | |
2457 | } | |
2458 | if (!scanned && !done) { | |
2459 | /* | |
2460 | * We hit the last page and there is more work to be done: wrap | |
2461 | * back to the start of the file | |
2462 | */ | |
2463 | scanned = 1; | |
2464 | index = 0; | |
2465 | goto retry; | |
2466 | } | |
d1310b2e CM |
2467 | return ret; |
2468 | } | |
d1310b2e | 2469 | |
d2c3f4f6 CM |
2470 | static noinline void flush_write_bio(void *data) |
2471 | { | |
2472 | struct extent_page_data *epd = data; | |
2473 | if (epd->bio) { | |
2474 | submit_one_bio(WRITE, epd->bio, 0, 0); | |
2475 | epd->bio = NULL; | |
2476 | } | |
2477 | } | |
2478 | ||
d1310b2e CM |
2479 | int extent_write_full_page(struct extent_io_tree *tree, struct page *page, |
2480 | get_extent_t *get_extent, | |
2481 | struct writeback_control *wbc) | |
2482 | { | |
2483 | int ret; | |
2484 | struct address_space *mapping = page->mapping; | |
2485 | struct extent_page_data epd = { | |
2486 | .bio = NULL, | |
2487 | .tree = tree, | |
2488 | .get_extent = get_extent, | |
771ed689 | 2489 | .extent_locked = 0, |
d1310b2e CM |
2490 | }; |
2491 | struct writeback_control wbc_writepages = { | |
2492 | .bdi = wbc->bdi, | |
2493 | .sync_mode = WB_SYNC_NONE, | |
2494 | .older_than_this = NULL, | |
2495 | .nr_to_write = 64, | |
2496 | .range_start = page_offset(page) + PAGE_CACHE_SIZE, | |
2497 | .range_end = (loff_t)-1, | |
2498 | }; | |
2499 | ||
2500 | ||
2501 | ret = __extent_writepage(page, wbc, &epd); | |
2502 | ||
4bef0848 | 2503 | extent_write_cache_pages(tree, mapping, &wbc_writepages, |
d2c3f4f6 | 2504 | __extent_writepage, &epd, flush_write_bio); |
d397712b | 2505 | if (epd.bio) |
c8b97818 | 2506 | submit_one_bio(WRITE, epd.bio, 0, 0); |
d1310b2e CM |
2507 | return ret; |
2508 | } | |
d1310b2e | 2509 | |
771ed689 CM |
2510 | int extent_write_locked_range(struct extent_io_tree *tree, struct inode *inode, |
2511 | u64 start, u64 end, get_extent_t *get_extent, | |
2512 | int mode) | |
2513 | { | |
2514 | int ret = 0; | |
2515 | struct address_space *mapping = inode->i_mapping; | |
2516 | struct page *page; | |
2517 | unsigned long nr_pages = (end - start + PAGE_CACHE_SIZE) >> | |
2518 | PAGE_CACHE_SHIFT; | |
2519 | ||
2520 | struct extent_page_data epd = { | |
2521 | .bio = NULL, | |
2522 | .tree = tree, | |
2523 | .get_extent = get_extent, | |
2524 | .extent_locked = 1, | |
2525 | }; | |
2526 | struct writeback_control wbc_writepages = { | |
2527 | .bdi = inode->i_mapping->backing_dev_info, | |
2528 | .sync_mode = mode, | |
2529 | .older_than_this = NULL, | |
2530 | .nr_to_write = nr_pages * 2, | |
2531 | .range_start = start, | |
2532 | .range_end = end + 1, | |
2533 | }; | |
2534 | ||
d397712b | 2535 | while (start <= end) { |
771ed689 CM |
2536 | page = find_get_page(mapping, start >> PAGE_CACHE_SHIFT); |
2537 | if (clear_page_dirty_for_io(page)) | |
2538 | ret = __extent_writepage(page, &wbc_writepages, &epd); | |
2539 | else { | |
2540 | if (tree->ops && tree->ops->writepage_end_io_hook) | |
2541 | tree->ops->writepage_end_io_hook(page, start, | |
2542 | start + PAGE_CACHE_SIZE - 1, | |
2543 | NULL, 1); | |
2544 | unlock_page(page); | |
2545 | } | |
2546 | page_cache_release(page); | |
2547 | start += PAGE_CACHE_SIZE; | |
2548 | } | |
2549 | ||
2550 | if (epd.bio) | |
2551 | submit_one_bio(WRITE, epd.bio, 0, 0); | |
2552 | return ret; | |
2553 | } | |
d1310b2e CM |
2554 | |
2555 | int extent_writepages(struct extent_io_tree *tree, | |
2556 | struct address_space *mapping, | |
2557 | get_extent_t *get_extent, | |
2558 | struct writeback_control *wbc) | |
2559 | { | |
2560 | int ret = 0; | |
2561 | struct extent_page_data epd = { | |
2562 | .bio = NULL, | |
2563 | .tree = tree, | |
2564 | .get_extent = get_extent, | |
771ed689 | 2565 | .extent_locked = 0, |
d1310b2e CM |
2566 | }; |
2567 | ||
4bef0848 | 2568 | ret = extent_write_cache_pages(tree, mapping, wbc, |
d2c3f4f6 CM |
2569 | __extent_writepage, &epd, |
2570 | flush_write_bio); | |
d397712b | 2571 | if (epd.bio) |
c8b97818 | 2572 | submit_one_bio(WRITE, epd.bio, 0, 0); |
d1310b2e CM |
2573 | return ret; |
2574 | } | |
d1310b2e CM |
2575 | |
2576 | int extent_readpages(struct extent_io_tree *tree, | |
2577 | struct address_space *mapping, | |
2578 | struct list_head *pages, unsigned nr_pages, | |
2579 | get_extent_t get_extent) | |
2580 | { | |
2581 | struct bio *bio = NULL; | |
2582 | unsigned page_idx; | |
2583 | struct pagevec pvec; | |
c8b97818 | 2584 | unsigned long bio_flags = 0; |
d1310b2e CM |
2585 | |
2586 | pagevec_init(&pvec, 0); | |
2587 | for (page_idx = 0; page_idx < nr_pages; page_idx++) { | |
2588 | struct page *page = list_entry(pages->prev, struct page, lru); | |
2589 | ||
2590 | prefetchw(&page->flags); | |
2591 | list_del(&page->lru); | |
2592 | /* | |
2593 | * what we want to do here is call add_to_page_cache_lru, | |
2594 | * but that isn't exported, so we reproduce it here | |
2595 | */ | |
2596 | if (!add_to_page_cache(page, mapping, | |
2597 | page->index, GFP_KERNEL)) { | |
2598 | ||
2599 | /* open coding of lru_cache_add, also not exported */ | |
2600 | page_cache_get(page); | |
2601 | if (!pagevec_add(&pvec, page)) | |
15916de8 | 2602 | __pagevec_lru_add_file(&pvec); |
f188591e | 2603 | __extent_read_full_page(tree, page, get_extent, |
c8b97818 | 2604 | &bio, 0, &bio_flags); |
d1310b2e CM |
2605 | } |
2606 | page_cache_release(page); | |
2607 | } | |
2608 | if (pagevec_count(&pvec)) | |
15916de8 | 2609 | __pagevec_lru_add_file(&pvec); |
d1310b2e CM |
2610 | BUG_ON(!list_empty(pages)); |
2611 | if (bio) | |
c8b97818 | 2612 | submit_one_bio(READ, bio, 0, bio_flags); |
d1310b2e CM |
2613 | return 0; |
2614 | } | |
d1310b2e CM |
2615 | |
2616 | /* | |
2617 | * basic invalidatepage code, this waits on any locked or writeback | |
2618 | * ranges corresponding to the page, and then deletes any extent state | |
2619 | * records from the tree | |
2620 | */ | |
2621 | int extent_invalidatepage(struct extent_io_tree *tree, | |
2622 | struct page *page, unsigned long offset) | |
2623 | { | |
2624 | u64 start = ((u64)page->index << PAGE_CACHE_SHIFT); | |
2625 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
2626 | size_t blocksize = page->mapping->host->i_sb->s_blocksize; | |
2627 | ||
d397712b | 2628 | start += (offset + blocksize - 1) & ~(blocksize - 1); |
d1310b2e CM |
2629 | if (start > end) |
2630 | return 0; | |
2631 | ||
2632 | lock_extent(tree, start, end, GFP_NOFS); | |
2633 | wait_on_extent_writeback(tree, start, end); | |
2634 | clear_extent_bit(tree, start, end, | |
2635 | EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC, | |
2636 | 1, 1, GFP_NOFS); | |
2637 | return 0; | |
2638 | } | |
d1310b2e CM |
2639 | |
2640 | /* | |
2641 | * simple commit_write call, set_range_dirty is used to mark both | |
2642 | * the pages and the extent records as dirty | |
2643 | */ | |
2644 | int extent_commit_write(struct extent_io_tree *tree, | |
2645 | struct inode *inode, struct page *page, | |
2646 | unsigned from, unsigned to) | |
2647 | { | |
2648 | loff_t pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to; | |
2649 | ||
2650 | set_page_extent_mapped(page); | |
2651 | set_page_dirty(page); | |
2652 | ||
2653 | if (pos > inode->i_size) { | |
2654 | i_size_write(inode, pos); | |
2655 | mark_inode_dirty(inode); | |
2656 | } | |
2657 | return 0; | |
2658 | } | |
d1310b2e CM |
2659 | |
2660 | int extent_prepare_write(struct extent_io_tree *tree, | |
2661 | struct inode *inode, struct page *page, | |
2662 | unsigned from, unsigned to, get_extent_t *get_extent) | |
2663 | { | |
2664 | u64 page_start = (u64)page->index << PAGE_CACHE_SHIFT; | |
2665 | u64 page_end = page_start + PAGE_CACHE_SIZE - 1; | |
2666 | u64 block_start; | |
2667 | u64 orig_block_start; | |
2668 | u64 block_end; | |
2669 | u64 cur_end; | |
2670 | struct extent_map *em; | |
2671 | unsigned blocksize = 1 << inode->i_blkbits; | |
2672 | size_t page_offset = 0; | |
2673 | size_t block_off_start; | |
2674 | size_t block_off_end; | |
2675 | int err = 0; | |
2676 | int iocount = 0; | |
2677 | int ret = 0; | |
2678 | int isnew; | |
2679 | ||
2680 | set_page_extent_mapped(page); | |
2681 | ||
2682 | block_start = (page_start + from) & ~((u64)blocksize - 1); | |
2683 | block_end = (page_start + to - 1) | (blocksize - 1); | |
2684 | orig_block_start = block_start; | |
2685 | ||
2686 | lock_extent(tree, page_start, page_end, GFP_NOFS); | |
d397712b | 2687 | while (block_start <= block_end) { |
d1310b2e CM |
2688 | em = get_extent(inode, page, page_offset, block_start, |
2689 | block_end - block_start + 1, 1); | |
d397712b | 2690 | if (IS_ERR(em) || !em) |
d1310b2e | 2691 | goto err; |
d397712b | 2692 | |
d1310b2e CM |
2693 | cur_end = min(block_end, extent_map_end(em) - 1); |
2694 | block_off_start = block_start & (PAGE_CACHE_SIZE - 1); | |
2695 | block_off_end = block_off_start + blocksize; | |
2696 | isnew = clear_extent_new(tree, block_start, cur_end, GFP_NOFS); | |
2697 | ||
2698 | if (!PageUptodate(page) && isnew && | |
2699 | (block_off_end > to || block_off_start < from)) { | |
2700 | void *kaddr; | |
2701 | ||
2702 | kaddr = kmap_atomic(page, KM_USER0); | |
2703 | if (block_off_end > to) | |
2704 | memset(kaddr + to, 0, block_off_end - to); | |
2705 | if (block_off_start < from) | |
2706 | memset(kaddr + block_off_start, 0, | |
2707 | from - block_off_start); | |
2708 | flush_dcache_page(page); | |
2709 | kunmap_atomic(kaddr, KM_USER0); | |
2710 | } | |
2711 | if ((em->block_start != EXTENT_MAP_HOLE && | |
2712 | em->block_start != EXTENT_MAP_INLINE) && | |
2713 | !isnew && !PageUptodate(page) && | |
2714 | (block_off_end > to || block_off_start < from) && | |
2715 | !test_range_bit(tree, block_start, cur_end, | |
2716 | EXTENT_UPTODATE, 1)) { | |
2717 | u64 sector; | |
2718 | u64 extent_offset = block_start - em->start; | |
2719 | size_t iosize; | |
2720 | sector = (em->block_start + extent_offset) >> 9; | |
2721 | iosize = (cur_end - block_start + blocksize) & | |
2722 | ~((u64)blocksize - 1); | |
2723 | /* | |
2724 | * we've already got the extent locked, but we | |
2725 | * need to split the state such that our end_bio | |
2726 | * handler can clear the lock. | |
2727 | */ | |
2728 | set_extent_bit(tree, block_start, | |
2729 | block_start + iosize - 1, | |
2730 | EXTENT_LOCKED, 0, NULL, GFP_NOFS); | |
2731 | ret = submit_extent_page(READ, tree, page, | |
2732 | sector, iosize, page_offset, em->bdev, | |
2733 | NULL, 1, | |
c8b97818 CM |
2734 | end_bio_extent_preparewrite, 0, |
2735 | 0, 0); | |
d1310b2e CM |
2736 | iocount++; |
2737 | block_start = block_start + iosize; | |
2738 | } else { | |
2739 | set_extent_uptodate(tree, block_start, cur_end, | |
2740 | GFP_NOFS); | |
2741 | unlock_extent(tree, block_start, cur_end, GFP_NOFS); | |
2742 | block_start = cur_end + 1; | |
2743 | } | |
2744 | page_offset = block_start & (PAGE_CACHE_SIZE - 1); | |
2745 | free_extent_map(em); | |
2746 | } | |
2747 | if (iocount) { | |
2748 | wait_extent_bit(tree, orig_block_start, | |
2749 | block_end, EXTENT_LOCKED); | |
2750 | } | |
2751 | check_page_uptodate(tree, page); | |
2752 | err: | |
2753 | /* FIXME, zero out newly allocated blocks on error */ | |
2754 | return err; | |
2755 | } | |
d1310b2e | 2756 | |
7b13b7b1 CM |
2757 | /* |
2758 | * a helper for releasepage, this tests for areas of the page that | |
2759 | * are locked or under IO and drops the related state bits if it is safe | |
2760 | * to drop the page. | |
2761 | */ | |
2762 | int try_release_extent_state(struct extent_map_tree *map, | |
2763 | struct extent_io_tree *tree, struct page *page, | |
2764 | gfp_t mask) | |
2765 | { | |
2766 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
2767 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
2768 | int ret = 1; | |
2769 | ||
211f90e6 CM |
2770 | if (test_range_bit(tree, start, end, |
2771 | EXTENT_IOBITS | EXTENT_ORDERED, 0)) | |
7b13b7b1 CM |
2772 | ret = 0; |
2773 | else { | |
2774 | if ((mask & GFP_NOFS) == GFP_NOFS) | |
2775 | mask = GFP_NOFS; | |
2776 | clear_extent_bit(tree, start, end, EXTENT_UPTODATE, | |
2777 | 1, 1, mask); | |
2778 | } | |
2779 | return ret; | |
2780 | } | |
7b13b7b1 | 2781 | |
d1310b2e CM |
2782 | /* |
2783 | * a helper for releasepage. As long as there are no locked extents | |
2784 | * in the range corresponding to the page, both state records and extent | |
2785 | * map records are removed | |
2786 | */ | |
2787 | int try_release_extent_mapping(struct extent_map_tree *map, | |
70dec807 CM |
2788 | struct extent_io_tree *tree, struct page *page, |
2789 | gfp_t mask) | |
d1310b2e CM |
2790 | { |
2791 | struct extent_map *em; | |
2792 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
2793 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
7b13b7b1 | 2794 | |
70dec807 CM |
2795 | if ((mask & __GFP_WAIT) && |
2796 | page->mapping->host->i_size > 16 * 1024 * 1024) { | |
39b5637f | 2797 | u64 len; |
70dec807 | 2798 | while (start <= end) { |
39b5637f | 2799 | len = end - start + 1; |
70dec807 | 2800 | spin_lock(&map->lock); |
39b5637f | 2801 | em = lookup_extent_mapping(map, start, len); |
70dec807 CM |
2802 | if (!em || IS_ERR(em)) { |
2803 | spin_unlock(&map->lock); | |
2804 | break; | |
2805 | } | |
7f3c74fb CM |
2806 | if (test_bit(EXTENT_FLAG_PINNED, &em->flags) || |
2807 | em->start != start) { | |
70dec807 CM |
2808 | spin_unlock(&map->lock); |
2809 | free_extent_map(em); | |
2810 | break; | |
2811 | } | |
2812 | if (!test_range_bit(tree, em->start, | |
2813 | extent_map_end(em) - 1, | |
c8b97818 CM |
2814 | EXTENT_LOCKED | EXTENT_WRITEBACK | |
2815 | EXTENT_ORDERED, | |
2816 | 0)) { | |
70dec807 CM |
2817 | remove_extent_mapping(map, em); |
2818 | /* once for the rb tree */ | |
2819 | free_extent_map(em); | |
2820 | } | |
2821 | start = extent_map_end(em); | |
d1310b2e | 2822 | spin_unlock(&map->lock); |
70dec807 CM |
2823 | |
2824 | /* once for us */ | |
d1310b2e CM |
2825 | free_extent_map(em); |
2826 | } | |
d1310b2e | 2827 | } |
7b13b7b1 | 2828 | return try_release_extent_state(map, tree, page, mask); |
d1310b2e | 2829 | } |
d1310b2e CM |
2830 | |
2831 | sector_t extent_bmap(struct address_space *mapping, sector_t iblock, | |
2832 | get_extent_t *get_extent) | |
2833 | { | |
2834 | struct inode *inode = mapping->host; | |
2835 | u64 start = iblock << inode->i_blkbits; | |
2836 | sector_t sector = 0; | |
d899e052 | 2837 | size_t blksize = (1 << inode->i_blkbits); |
d1310b2e CM |
2838 | struct extent_map *em; |
2839 | ||
d899e052 YZ |
2840 | lock_extent(&BTRFS_I(inode)->io_tree, start, start + blksize - 1, |
2841 | GFP_NOFS); | |
2842 | em = get_extent(inode, NULL, 0, start, blksize, 0); | |
2843 | unlock_extent(&BTRFS_I(inode)->io_tree, start, start + blksize - 1, | |
2844 | GFP_NOFS); | |
d1310b2e CM |
2845 | if (!em || IS_ERR(em)) |
2846 | return 0; | |
2847 | ||
d899e052 | 2848 | if (em->block_start > EXTENT_MAP_LAST_BYTE) |
d1310b2e CM |
2849 | goto out; |
2850 | ||
2851 | sector = (em->block_start + start - em->start) >> inode->i_blkbits; | |
d1310b2e CM |
2852 | out: |
2853 | free_extent_map(em); | |
2854 | return sector; | |
2855 | } | |
2856 | ||
1506fcc8 YS |
2857 | int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, |
2858 | __u64 start, __u64 len, get_extent_t *get_extent) | |
2859 | { | |
2860 | int ret; | |
2861 | u64 off = start; | |
2862 | u64 max = start + len; | |
2863 | u32 flags = 0; | |
2864 | u64 disko = 0; | |
2865 | struct extent_map *em = NULL; | |
2866 | int end = 0; | |
2867 | u64 em_start = 0, em_len = 0; | |
2868 | unsigned long emflags; | |
2869 | ret = 0; | |
2870 | ||
2871 | if (len == 0) | |
2872 | return -EINVAL; | |
2873 | ||
2874 | lock_extent(&BTRFS_I(inode)->io_tree, start, start + len, | |
2875 | GFP_NOFS); | |
2876 | em = get_extent(inode, NULL, 0, off, max - off, 0); | |
2877 | if (!em) | |
2878 | goto out; | |
2879 | if (IS_ERR(em)) { | |
2880 | ret = PTR_ERR(em); | |
2881 | goto out; | |
2882 | } | |
2883 | while (!end) { | |
2884 | off = em->start + em->len; | |
2885 | if (off >= max) | |
2886 | end = 1; | |
2887 | ||
2888 | em_start = em->start; | |
2889 | em_len = em->len; | |
2890 | ||
2891 | disko = 0; | |
2892 | flags = 0; | |
2893 | ||
2894 | switch (em->block_start) { | |
2895 | case EXTENT_MAP_LAST_BYTE: | |
2896 | end = 1; | |
2897 | flags |= FIEMAP_EXTENT_LAST; | |
2898 | break; | |
2899 | case EXTENT_MAP_HOLE: | |
2900 | flags |= FIEMAP_EXTENT_UNWRITTEN; | |
2901 | break; | |
2902 | case EXTENT_MAP_INLINE: | |
2903 | flags |= (FIEMAP_EXTENT_DATA_INLINE | | |
2904 | FIEMAP_EXTENT_NOT_ALIGNED); | |
2905 | break; | |
2906 | case EXTENT_MAP_DELALLOC: | |
2907 | flags |= (FIEMAP_EXTENT_DELALLOC | | |
2908 | FIEMAP_EXTENT_UNKNOWN); | |
2909 | break; | |
2910 | default: | |
2911 | disko = em->block_start; | |
2912 | break; | |
2913 | } | |
2914 | if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) | |
2915 | flags |= FIEMAP_EXTENT_ENCODED; | |
2916 | ||
2917 | emflags = em->flags; | |
2918 | free_extent_map(em); | |
2919 | em = NULL; | |
2920 | ||
2921 | if (!end) { | |
2922 | em = get_extent(inode, NULL, 0, off, max - off, 0); | |
2923 | if (!em) | |
2924 | goto out; | |
2925 | if (IS_ERR(em)) { | |
2926 | ret = PTR_ERR(em); | |
2927 | goto out; | |
2928 | } | |
2929 | emflags = em->flags; | |
2930 | } | |
2931 | if (test_bit(EXTENT_FLAG_VACANCY, &emflags)) { | |
2932 | flags |= FIEMAP_EXTENT_LAST; | |
2933 | end = 1; | |
2934 | } | |
2935 | ||
2936 | ret = fiemap_fill_next_extent(fieinfo, em_start, disko, | |
2937 | em_len, flags); | |
2938 | if (ret) | |
2939 | goto out_free; | |
2940 | } | |
2941 | out_free: | |
2942 | free_extent_map(em); | |
2943 | out: | |
2944 | unlock_extent(&BTRFS_I(inode)->io_tree, start, start + len, | |
2945 | GFP_NOFS); | |
2946 | return ret; | |
2947 | } | |
2948 | ||
d1310b2e CM |
2949 | static inline struct page *extent_buffer_page(struct extent_buffer *eb, |
2950 | unsigned long i) | |
2951 | { | |
2952 | struct page *p; | |
2953 | struct address_space *mapping; | |
2954 | ||
2955 | if (i == 0) | |
2956 | return eb->first_page; | |
2957 | i += eb->start >> PAGE_CACHE_SHIFT; | |
2958 | mapping = eb->first_page->mapping; | |
33958dc6 CM |
2959 | if (!mapping) |
2960 | return NULL; | |
0ee0fda0 SW |
2961 | |
2962 | /* | |
2963 | * extent_buffer_page is only called after pinning the page | |
2964 | * by increasing the reference count. So we know the page must | |
2965 | * be in the radix tree. | |
2966 | */ | |
0ee0fda0 | 2967 | rcu_read_lock(); |
d1310b2e | 2968 | p = radix_tree_lookup(&mapping->page_tree, i); |
0ee0fda0 | 2969 | rcu_read_unlock(); |
2b1f55b0 | 2970 | |
d1310b2e CM |
2971 | return p; |
2972 | } | |
2973 | ||
6af118ce | 2974 | static inline unsigned long num_extent_pages(u64 start, u64 len) |
728131d8 | 2975 | { |
6af118ce CM |
2976 | return ((start + len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT) - |
2977 | (start >> PAGE_CACHE_SHIFT); | |
728131d8 CM |
2978 | } |
2979 | ||
d1310b2e CM |
2980 | static struct extent_buffer *__alloc_extent_buffer(struct extent_io_tree *tree, |
2981 | u64 start, | |
2982 | unsigned long len, | |
2983 | gfp_t mask) | |
2984 | { | |
2985 | struct extent_buffer *eb = NULL; | |
3935127c | 2986 | #if LEAK_DEBUG |
2d2ae547 | 2987 | unsigned long flags; |
4bef0848 | 2988 | #endif |
d1310b2e | 2989 | |
d1310b2e | 2990 | eb = kmem_cache_zalloc(extent_buffer_cache, mask); |
d1310b2e CM |
2991 | eb->start = start; |
2992 | eb->len = len; | |
a61e6f29 | 2993 | mutex_init(&eb->mutex); |
3935127c | 2994 | #if LEAK_DEBUG |
2d2ae547 CM |
2995 | spin_lock_irqsave(&leak_lock, flags); |
2996 | list_add(&eb->leak_list, &buffers); | |
2997 | spin_unlock_irqrestore(&leak_lock, flags); | |
4bef0848 | 2998 | #endif |
d1310b2e CM |
2999 | atomic_set(&eb->refs, 1); |
3000 | ||
3001 | return eb; | |
3002 | } | |
3003 | ||
3004 | static void __free_extent_buffer(struct extent_buffer *eb) | |
3005 | { | |
3935127c | 3006 | #if LEAK_DEBUG |
2d2ae547 CM |
3007 | unsigned long flags; |
3008 | spin_lock_irqsave(&leak_lock, flags); | |
3009 | list_del(&eb->leak_list); | |
3010 | spin_unlock_irqrestore(&leak_lock, flags); | |
4bef0848 | 3011 | #endif |
d1310b2e CM |
3012 | kmem_cache_free(extent_buffer_cache, eb); |
3013 | } | |
3014 | ||
3015 | struct extent_buffer *alloc_extent_buffer(struct extent_io_tree *tree, | |
3016 | u64 start, unsigned long len, | |
3017 | struct page *page0, | |
3018 | gfp_t mask) | |
3019 | { | |
3020 | unsigned long num_pages = num_extent_pages(start, len); | |
3021 | unsigned long i; | |
3022 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
3023 | struct extent_buffer *eb; | |
6af118ce | 3024 | struct extent_buffer *exists = NULL; |
d1310b2e CM |
3025 | struct page *p; |
3026 | struct address_space *mapping = tree->mapping; | |
3027 | int uptodate = 1; | |
3028 | ||
6af118ce CM |
3029 | spin_lock(&tree->buffer_lock); |
3030 | eb = buffer_search(tree, start); | |
3031 | if (eb) { | |
3032 | atomic_inc(&eb->refs); | |
3033 | spin_unlock(&tree->buffer_lock); | |
0f9dd46c | 3034 | mark_page_accessed(eb->first_page); |
6af118ce CM |
3035 | return eb; |
3036 | } | |
3037 | spin_unlock(&tree->buffer_lock); | |
3038 | ||
d1310b2e | 3039 | eb = __alloc_extent_buffer(tree, start, len, mask); |
2b114d1d | 3040 | if (!eb) |
d1310b2e CM |
3041 | return NULL; |
3042 | ||
d1310b2e CM |
3043 | if (page0) { |
3044 | eb->first_page = page0; | |
3045 | i = 1; | |
3046 | index++; | |
3047 | page_cache_get(page0); | |
3048 | mark_page_accessed(page0); | |
3049 | set_page_extent_mapped(page0); | |
d1310b2e | 3050 | set_page_extent_head(page0, len); |
f188591e | 3051 | uptodate = PageUptodate(page0); |
d1310b2e CM |
3052 | } else { |
3053 | i = 0; | |
3054 | } | |
3055 | for (; i < num_pages; i++, index++) { | |
3056 | p = find_or_create_page(mapping, index, mask | __GFP_HIGHMEM); | |
3057 | if (!p) { | |
3058 | WARN_ON(1); | |
6af118ce | 3059 | goto free_eb; |
d1310b2e CM |
3060 | } |
3061 | set_page_extent_mapped(p); | |
3062 | mark_page_accessed(p); | |
3063 | if (i == 0) { | |
3064 | eb->first_page = p; | |
3065 | set_page_extent_head(p, len); | |
3066 | } else { | |
3067 | set_page_private(p, EXTENT_PAGE_PRIVATE); | |
3068 | } | |
3069 | if (!PageUptodate(p)) | |
3070 | uptodate = 0; | |
3071 | unlock_page(p); | |
3072 | } | |
3073 | if (uptodate) | |
3074 | eb->flags |= EXTENT_UPTODATE; | |
3075 | eb->flags |= EXTENT_BUFFER_FILLED; | |
3076 | ||
6af118ce CM |
3077 | spin_lock(&tree->buffer_lock); |
3078 | exists = buffer_tree_insert(tree, start, &eb->rb_node); | |
3079 | if (exists) { | |
3080 | /* add one reference for the caller */ | |
3081 | atomic_inc(&exists->refs); | |
3082 | spin_unlock(&tree->buffer_lock); | |
3083 | goto free_eb; | |
3084 | } | |
3085 | spin_unlock(&tree->buffer_lock); | |
3086 | ||
3087 | /* add one reference for the tree */ | |
3088 | atomic_inc(&eb->refs); | |
d1310b2e CM |
3089 | return eb; |
3090 | ||
6af118ce | 3091 | free_eb: |
d1310b2e | 3092 | if (!atomic_dec_and_test(&eb->refs)) |
6af118ce CM |
3093 | return exists; |
3094 | for (index = 1; index < i; index++) | |
d1310b2e | 3095 | page_cache_release(extent_buffer_page(eb, index)); |
6af118ce | 3096 | page_cache_release(extent_buffer_page(eb, 0)); |
d1310b2e | 3097 | __free_extent_buffer(eb); |
6af118ce | 3098 | return exists; |
d1310b2e | 3099 | } |
d1310b2e CM |
3100 | |
3101 | struct extent_buffer *find_extent_buffer(struct extent_io_tree *tree, | |
3102 | u64 start, unsigned long len, | |
3103 | gfp_t mask) | |
3104 | { | |
d1310b2e | 3105 | struct extent_buffer *eb; |
d1310b2e | 3106 | |
6af118ce CM |
3107 | spin_lock(&tree->buffer_lock); |
3108 | eb = buffer_search(tree, start); | |
3109 | if (eb) | |
3110 | atomic_inc(&eb->refs); | |
3111 | spin_unlock(&tree->buffer_lock); | |
d1310b2e | 3112 | |
0f9dd46c JB |
3113 | if (eb) |
3114 | mark_page_accessed(eb->first_page); | |
3115 | ||
d1310b2e | 3116 | return eb; |
d1310b2e | 3117 | } |
d1310b2e CM |
3118 | |
3119 | void free_extent_buffer(struct extent_buffer *eb) | |
3120 | { | |
d1310b2e CM |
3121 | if (!eb) |
3122 | return; | |
3123 | ||
3124 | if (!atomic_dec_and_test(&eb->refs)) | |
3125 | return; | |
3126 | ||
6af118ce | 3127 | WARN_ON(1); |
d1310b2e | 3128 | } |
d1310b2e CM |
3129 | |
3130 | int clear_extent_buffer_dirty(struct extent_io_tree *tree, | |
3131 | struct extent_buffer *eb) | |
3132 | { | |
3133 | int set; | |
3134 | unsigned long i; | |
3135 | unsigned long num_pages; | |
3136 | struct page *page; | |
3137 | ||
3138 | u64 start = eb->start; | |
3139 | u64 end = start + eb->len - 1; | |
3140 | ||
3141 | set = clear_extent_dirty(tree, start, end, GFP_NOFS); | |
3142 | num_pages = num_extent_pages(eb->start, eb->len); | |
3143 | ||
3144 | for (i = 0; i < num_pages; i++) { | |
3145 | page = extent_buffer_page(eb, i); | |
d2c3f4f6 CM |
3146 | if (!set && !PageDirty(page)) |
3147 | continue; | |
3148 | ||
a61e6f29 | 3149 | lock_page(page); |
d1310b2e CM |
3150 | if (i == 0) |
3151 | set_page_extent_head(page, eb->len); | |
3152 | else | |
3153 | set_page_private(page, EXTENT_PAGE_PRIVATE); | |
3154 | ||
3155 | /* | |
3156 | * if we're on the last page or the first page and the | |
3157 | * block isn't aligned on a page boundary, do extra checks | |
3158 | * to make sure we don't clean page that is partially dirty | |
3159 | */ | |
3160 | if ((i == 0 && (eb->start & (PAGE_CACHE_SIZE - 1))) || | |
3161 | ((i == num_pages - 1) && | |
3162 | ((eb->start + eb->len) & (PAGE_CACHE_SIZE - 1)))) { | |
3163 | start = (u64)page->index << PAGE_CACHE_SHIFT; | |
3164 | end = start + PAGE_CACHE_SIZE - 1; | |
3165 | if (test_range_bit(tree, start, end, | |
3166 | EXTENT_DIRTY, 0)) { | |
a61e6f29 | 3167 | unlock_page(page); |
d1310b2e CM |
3168 | continue; |
3169 | } | |
3170 | } | |
3171 | clear_page_dirty_for_io(page); | |
0ee0fda0 | 3172 | spin_lock_irq(&page->mapping->tree_lock); |
d1310b2e CM |
3173 | if (!PageDirty(page)) { |
3174 | radix_tree_tag_clear(&page->mapping->page_tree, | |
3175 | page_index(page), | |
3176 | PAGECACHE_TAG_DIRTY); | |
3177 | } | |
0ee0fda0 | 3178 | spin_unlock_irq(&page->mapping->tree_lock); |
a61e6f29 | 3179 | unlock_page(page); |
d1310b2e CM |
3180 | } |
3181 | return 0; | |
3182 | } | |
d1310b2e CM |
3183 | |
3184 | int wait_on_extent_buffer_writeback(struct extent_io_tree *tree, | |
3185 | struct extent_buffer *eb) | |
3186 | { | |
3187 | return wait_on_extent_writeback(tree, eb->start, | |
3188 | eb->start + eb->len - 1); | |
3189 | } | |
d1310b2e CM |
3190 | |
3191 | int set_extent_buffer_dirty(struct extent_io_tree *tree, | |
3192 | struct extent_buffer *eb) | |
3193 | { | |
3194 | unsigned long i; | |
3195 | unsigned long num_pages; | |
3196 | ||
3197 | num_pages = num_extent_pages(eb->start, eb->len); | |
3198 | for (i = 0; i < num_pages; i++) { | |
3199 | struct page *page = extent_buffer_page(eb, i); | |
3200 | /* writepage may need to do something special for the | |
3201 | * first page, we have to make sure page->private is | |
3202 | * properly set. releasepage may drop page->private | |
3203 | * on us if the page isn't already dirty. | |
3204 | */ | |
a1b32a59 | 3205 | lock_page(page); |
d1310b2e | 3206 | if (i == 0) { |
d1310b2e CM |
3207 | set_page_extent_head(page, eb->len); |
3208 | } else if (PagePrivate(page) && | |
3209 | page->private != EXTENT_PAGE_PRIVATE) { | |
d1310b2e | 3210 | set_page_extent_mapped(page); |
d1310b2e CM |
3211 | } |
3212 | __set_page_dirty_nobuffers(extent_buffer_page(eb, i)); | |
a1b32a59 | 3213 | set_extent_dirty(tree, page_offset(page), |
d397712b | 3214 | page_offset(page) + PAGE_CACHE_SIZE - 1, |
a1b32a59 CM |
3215 | GFP_NOFS); |
3216 | unlock_page(page); | |
d1310b2e | 3217 | } |
a1b32a59 | 3218 | return 0; |
d1310b2e | 3219 | } |
d1310b2e | 3220 | |
1259ab75 CM |
3221 | int clear_extent_buffer_uptodate(struct extent_io_tree *tree, |
3222 | struct extent_buffer *eb) | |
3223 | { | |
3224 | unsigned long i; | |
3225 | struct page *page; | |
3226 | unsigned long num_pages; | |
3227 | ||
3228 | num_pages = num_extent_pages(eb->start, eb->len); | |
3229 | eb->flags &= ~EXTENT_UPTODATE; | |
3230 | ||
3231 | clear_extent_uptodate(tree, eb->start, eb->start + eb->len - 1, | |
3232 | GFP_NOFS); | |
3233 | for (i = 0; i < num_pages; i++) { | |
3234 | page = extent_buffer_page(eb, i); | |
33958dc6 CM |
3235 | if (page) |
3236 | ClearPageUptodate(page); | |
1259ab75 CM |
3237 | } |
3238 | return 0; | |
3239 | } | |
3240 | ||
d1310b2e CM |
3241 | int set_extent_buffer_uptodate(struct extent_io_tree *tree, |
3242 | struct extent_buffer *eb) | |
3243 | { | |
3244 | unsigned long i; | |
3245 | struct page *page; | |
3246 | unsigned long num_pages; | |
3247 | ||
3248 | num_pages = num_extent_pages(eb->start, eb->len); | |
3249 | ||
3250 | set_extent_uptodate(tree, eb->start, eb->start + eb->len - 1, | |
3251 | GFP_NOFS); | |
3252 | for (i = 0; i < num_pages; i++) { | |
3253 | page = extent_buffer_page(eb, i); | |
3254 | if ((i == 0 && (eb->start & (PAGE_CACHE_SIZE - 1))) || | |
3255 | ((i == num_pages - 1) && | |
3256 | ((eb->start + eb->len) & (PAGE_CACHE_SIZE - 1)))) { | |
3257 | check_page_uptodate(tree, page); | |
3258 | continue; | |
3259 | } | |
3260 | SetPageUptodate(page); | |
3261 | } | |
3262 | return 0; | |
3263 | } | |
d1310b2e | 3264 | |
ce9adaa5 CM |
3265 | int extent_range_uptodate(struct extent_io_tree *tree, |
3266 | u64 start, u64 end) | |
3267 | { | |
3268 | struct page *page; | |
3269 | int ret; | |
3270 | int pg_uptodate = 1; | |
3271 | int uptodate; | |
3272 | unsigned long index; | |
3273 | ||
3274 | ret = test_range_bit(tree, start, end, EXTENT_UPTODATE, 1); | |
3275 | if (ret) | |
3276 | return 1; | |
d397712b | 3277 | while (start <= end) { |
ce9adaa5 CM |
3278 | index = start >> PAGE_CACHE_SHIFT; |
3279 | page = find_get_page(tree->mapping, index); | |
3280 | uptodate = PageUptodate(page); | |
3281 | page_cache_release(page); | |
3282 | if (!uptodate) { | |
3283 | pg_uptodate = 0; | |
3284 | break; | |
3285 | } | |
3286 | start += PAGE_CACHE_SIZE; | |
3287 | } | |
3288 | return pg_uptodate; | |
3289 | } | |
3290 | ||
d1310b2e | 3291 | int extent_buffer_uptodate(struct extent_io_tree *tree, |
ce9adaa5 | 3292 | struct extent_buffer *eb) |
d1310b2e | 3293 | { |
728131d8 | 3294 | int ret = 0; |
ce9adaa5 CM |
3295 | unsigned long num_pages; |
3296 | unsigned long i; | |
728131d8 CM |
3297 | struct page *page; |
3298 | int pg_uptodate = 1; | |
3299 | ||
d1310b2e | 3300 | if (eb->flags & EXTENT_UPTODATE) |
4235298e | 3301 | return 1; |
728131d8 | 3302 | |
4235298e | 3303 | ret = test_range_bit(tree, eb->start, eb->start + eb->len - 1, |
d1310b2e | 3304 | EXTENT_UPTODATE, 1); |
4235298e CM |
3305 | if (ret) |
3306 | return ret; | |
728131d8 CM |
3307 | |
3308 | num_pages = num_extent_pages(eb->start, eb->len); | |
3309 | for (i = 0; i < num_pages; i++) { | |
3310 | page = extent_buffer_page(eb, i); | |
3311 | if (!PageUptodate(page)) { | |
3312 | pg_uptodate = 0; | |
3313 | break; | |
3314 | } | |
3315 | } | |
4235298e | 3316 | return pg_uptodate; |
d1310b2e | 3317 | } |
d1310b2e CM |
3318 | |
3319 | int read_extent_buffer_pages(struct extent_io_tree *tree, | |
3320 | struct extent_buffer *eb, | |
a86c12c7 | 3321 | u64 start, int wait, |
f188591e | 3322 | get_extent_t *get_extent, int mirror_num) |
d1310b2e CM |
3323 | { |
3324 | unsigned long i; | |
3325 | unsigned long start_i; | |
3326 | struct page *page; | |
3327 | int err; | |
3328 | int ret = 0; | |
ce9adaa5 CM |
3329 | int locked_pages = 0; |
3330 | int all_uptodate = 1; | |
3331 | int inc_all_pages = 0; | |
d1310b2e | 3332 | unsigned long num_pages; |
a86c12c7 | 3333 | struct bio *bio = NULL; |
c8b97818 | 3334 | unsigned long bio_flags = 0; |
a86c12c7 | 3335 | |
d1310b2e CM |
3336 | if (eb->flags & EXTENT_UPTODATE) |
3337 | return 0; | |
3338 | ||
ce9adaa5 | 3339 | if (test_range_bit(tree, eb->start, eb->start + eb->len - 1, |
d1310b2e CM |
3340 | EXTENT_UPTODATE, 1)) { |
3341 | return 0; | |
3342 | } | |
3343 | ||
3344 | if (start) { | |
3345 | WARN_ON(start < eb->start); | |
3346 | start_i = (start >> PAGE_CACHE_SHIFT) - | |
3347 | (eb->start >> PAGE_CACHE_SHIFT); | |
3348 | } else { | |
3349 | start_i = 0; | |
3350 | } | |
3351 | ||
3352 | num_pages = num_extent_pages(eb->start, eb->len); | |
3353 | for (i = start_i; i < num_pages; i++) { | |
3354 | page = extent_buffer_page(eb, i); | |
d1310b2e | 3355 | if (!wait) { |
2db04966 | 3356 | if (!trylock_page(page)) |
ce9adaa5 | 3357 | goto unlock_exit; |
d1310b2e CM |
3358 | } else { |
3359 | lock_page(page); | |
3360 | } | |
ce9adaa5 | 3361 | locked_pages++; |
d397712b | 3362 | if (!PageUptodate(page)) |
ce9adaa5 | 3363 | all_uptodate = 0; |
ce9adaa5 CM |
3364 | } |
3365 | if (all_uptodate) { | |
3366 | if (start_i == 0) | |
3367 | eb->flags |= EXTENT_UPTODATE; | |
3368 | goto unlock_exit; | |
3369 | } | |
3370 | ||
3371 | for (i = start_i; i < num_pages; i++) { | |
3372 | page = extent_buffer_page(eb, i); | |
3373 | if (inc_all_pages) | |
3374 | page_cache_get(page); | |
3375 | if (!PageUptodate(page)) { | |
3376 | if (start_i == 0) | |
3377 | inc_all_pages = 1; | |
f188591e | 3378 | ClearPageError(page); |
a86c12c7 | 3379 | err = __extent_read_full_page(tree, page, |
f188591e | 3380 | get_extent, &bio, |
c8b97818 | 3381 | mirror_num, &bio_flags); |
d397712b | 3382 | if (err) |
d1310b2e | 3383 | ret = err; |
d1310b2e CM |
3384 | } else { |
3385 | unlock_page(page); | |
3386 | } | |
3387 | } | |
3388 | ||
a86c12c7 | 3389 | if (bio) |
c8b97818 | 3390 | submit_one_bio(READ, bio, mirror_num, bio_flags); |
a86c12c7 | 3391 | |
d397712b | 3392 | if (ret || !wait) |
d1310b2e | 3393 | return ret; |
d397712b | 3394 | |
d1310b2e CM |
3395 | for (i = start_i; i < num_pages; i++) { |
3396 | page = extent_buffer_page(eb, i); | |
3397 | wait_on_page_locked(page); | |
d397712b | 3398 | if (!PageUptodate(page)) |
d1310b2e | 3399 | ret = -EIO; |
d1310b2e | 3400 | } |
d397712b | 3401 | |
d1310b2e CM |
3402 | if (!ret) |
3403 | eb->flags |= EXTENT_UPTODATE; | |
3404 | return ret; | |
ce9adaa5 CM |
3405 | |
3406 | unlock_exit: | |
3407 | i = start_i; | |
d397712b | 3408 | while (locked_pages > 0) { |
ce9adaa5 CM |
3409 | page = extent_buffer_page(eb, i); |
3410 | i++; | |
3411 | unlock_page(page); | |
3412 | locked_pages--; | |
3413 | } | |
3414 | return ret; | |
d1310b2e | 3415 | } |
d1310b2e CM |
3416 | |
3417 | void read_extent_buffer(struct extent_buffer *eb, void *dstv, | |
3418 | unsigned long start, | |
3419 | unsigned long len) | |
3420 | { | |
3421 | size_t cur; | |
3422 | size_t offset; | |
3423 | struct page *page; | |
3424 | char *kaddr; | |
3425 | char *dst = (char *)dstv; | |
3426 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3427 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
d1310b2e CM |
3428 | |
3429 | WARN_ON(start > eb->len); | |
3430 | WARN_ON(start + len > eb->start + eb->len); | |
3431 | ||
3432 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3433 | ||
d397712b | 3434 | while (len > 0) { |
d1310b2e | 3435 | page = extent_buffer_page(eb, i); |
d1310b2e CM |
3436 | |
3437 | cur = min(len, (PAGE_CACHE_SIZE - offset)); | |
3438 | kaddr = kmap_atomic(page, KM_USER1); | |
3439 | memcpy(dst, kaddr + offset, cur); | |
3440 | kunmap_atomic(kaddr, KM_USER1); | |
3441 | ||
3442 | dst += cur; | |
3443 | len -= cur; | |
3444 | offset = 0; | |
3445 | i++; | |
3446 | } | |
3447 | } | |
d1310b2e CM |
3448 | |
3449 | int map_private_extent_buffer(struct extent_buffer *eb, unsigned long start, | |
3450 | unsigned long min_len, char **token, char **map, | |
3451 | unsigned long *map_start, | |
3452 | unsigned long *map_len, int km) | |
3453 | { | |
3454 | size_t offset = start & (PAGE_CACHE_SIZE - 1); | |
3455 | char *kaddr; | |
3456 | struct page *p; | |
3457 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3458 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
3459 | unsigned long end_i = (start_offset + start + min_len - 1) >> | |
3460 | PAGE_CACHE_SHIFT; | |
3461 | ||
3462 | if (i != end_i) | |
3463 | return -EINVAL; | |
3464 | ||
3465 | if (i == 0) { | |
3466 | offset = start_offset; | |
3467 | *map_start = 0; | |
3468 | } else { | |
3469 | offset = 0; | |
3470 | *map_start = ((u64)i << PAGE_CACHE_SHIFT) - start_offset; | |
3471 | } | |
d397712b | 3472 | |
d1310b2e | 3473 | if (start + min_len > eb->len) { |
d397712b CM |
3474 | printk(KERN_ERR "btrfs bad mapping eb start %llu len %lu, " |
3475 | "wanted %lu %lu\n", (unsigned long long)eb->start, | |
3476 | eb->len, start, min_len); | |
d1310b2e CM |
3477 | WARN_ON(1); |
3478 | } | |
3479 | ||
3480 | p = extent_buffer_page(eb, i); | |
d1310b2e CM |
3481 | kaddr = kmap_atomic(p, km); |
3482 | *token = kaddr; | |
3483 | *map = kaddr + offset; | |
3484 | *map_len = PAGE_CACHE_SIZE - offset; | |
3485 | return 0; | |
3486 | } | |
d1310b2e CM |
3487 | |
3488 | int map_extent_buffer(struct extent_buffer *eb, unsigned long start, | |
3489 | unsigned long min_len, | |
3490 | char **token, char **map, | |
3491 | unsigned long *map_start, | |
3492 | unsigned long *map_len, int km) | |
3493 | { | |
3494 | int err; | |
3495 | int save = 0; | |
3496 | if (eb->map_token) { | |
3497 | unmap_extent_buffer(eb, eb->map_token, km); | |
3498 | eb->map_token = NULL; | |
3499 | save = 1; | |
934d375b | 3500 | WARN_ON(!mutex_is_locked(&eb->mutex)); |
d1310b2e CM |
3501 | } |
3502 | err = map_private_extent_buffer(eb, start, min_len, token, map, | |
3503 | map_start, map_len, km); | |
3504 | if (!err && save) { | |
3505 | eb->map_token = *token; | |
3506 | eb->kaddr = *map; | |
3507 | eb->map_start = *map_start; | |
3508 | eb->map_len = *map_len; | |
3509 | } | |
3510 | return err; | |
3511 | } | |
d1310b2e CM |
3512 | |
3513 | void unmap_extent_buffer(struct extent_buffer *eb, char *token, int km) | |
3514 | { | |
3515 | kunmap_atomic(token, km); | |
3516 | } | |
d1310b2e CM |
3517 | |
3518 | int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv, | |
3519 | unsigned long start, | |
3520 | unsigned long len) | |
3521 | { | |
3522 | size_t cur; | |
3523 | size_t offset; | |
3524 | struct page *page; | |
3525 | char *kaddr; | |
3526 | char *ptr = (char *)ptrv; | |
3527 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3528 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
3529 | int ret = 0; | |
3530 | ||
3531 | WARN_ON(start > eb->len); | |
3532 | WARN_ON(start + len > eb->start + eb->len); | |
3533 | ||
3534 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3535 | ||
d397712b | 3536 | while (len > 0) { |
d1310b2e | 3537 | page = extent_buffer_page(eb, i); |
d1310b2e CM |
3538 | |
3539 | cur = min(len, (PAGE_CACHE_SIZE - offset)); | |
3540 | ||
3541 | kaddr = kmap_atomic(page, KM_USER0); | |
3542 | ret = memcmp(ptr, kaddr + offset, cur); | |
3543 | kunmap_atomic(kaddr, KM_USER0); | |
3544 | if (ret) | |
3545 | break; | |
3546 | ||
3547 | ptr += cur; | |
3548 | len -= cur; | |
3549 | offset = 0; | |
3550 | i++; | |
3551 | } | |
3552 | return ret; | |
3553 | } | |
d1310b2e CM |
3554 | |
3555 | void write_extent_buffer(struct extent_buffer *eb, const void *srcv, | |
3556 | unsigned long start, unsigned long len) | |
3557 | { | |
3558 | size_t cur; | |
3559 | size_t offset; | |
3560 | struct page *page; | |
3561 | char *kaddr; | |
3562 | char *src = (char *)srcv; | |
3563 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3564 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
3565 | ||
3566 | WARN_ON(start > eb->len); | |
3567 | WARN_ON(start + len > eb->start + eb->len); | |
3568 | ||
3569 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3570 | ||
d397712b | 3571 | while (len > 0) { |
d1310b2e CM |
3572 | page = extent_buffer_page(eb, i); |
3573 | WARN_ON(!PageUptodate(page)); | |
3574 | ||
3575 | cur = min(len, PAGE_CACHE_SIZE - offset); | |
3576 | kaddr = kmap_atomic(page, KM_USER1); | |
3577 | memcpy(kaddr + offset, src, cur); | |
3578 | kunmap_atomic(kaddr, KM_USER1); | |
3579 | ||
3580 | src += cur; | |
3581 | len -= cur; | |
3582 | offset = 0; | |
3583 | i++; | |
3584 | } | |
3585 | } | |
d1310b2e CM |
3586 | |
3587 | void memset_extent_buffer(struct extent_buffer *eb, char c, | |
3588 | unsigned long start, unsigned long len) | |
3589 | { | |
3590 | size_t cur; | |
3591 | size_t offset; | |
3592 | struct page *page; | |
3593 | char *kaddr; | |
3594 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3595 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
3596 | ||
3597 | WARN_ON(start > eb->len); | |
3598 | WARN_ON(start + len > eb->start + eb->len); | |
3599 | ||
3600 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3601 | ||
d397712b | 3602 | while (len > 0) { |
d1310b2e CM |
3603 | page = extent_buffer_page(eb, i); |
3604 | WARN_ON(!PageUptodate(page)); | |
3605 | ||
3606 | cur = min(len, PAGE_CACHE_SIZE - offset); | |
3607 | kaddr = kmap_atomic(page, KM_USER0); | |
3608 | memset(kaddr + offset, c, cur); | |
3609 | kunmap_atomic(kaddr, KM_USER0); | |
3610 | ||
3611 | len -= cur; | |
3612 | offset = 0; | |
3613 | i++; | |
3614 | } | |
3615 | } | |
d1310b2e CM |
3616 | |
3617 | void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src, | |
3618 | unsigned long dst_offset, unsigned long src_offset, | |
3619 | unsigned long len) | |
3620 | { | |
3621 | u64 dst_len = dst->len; | |
3622 | size_t cur; | |
3623 | size_t offset; | |
3624 | struct page *page; | |
3625 | char *kaddr; | |
3626 | size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3627 | unsigned long i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT; | |
3628 | ||
3629 | WARN_ON(src->len != dst_len); | |
3630 | ||
3631 | offset = (start_offset + dst_offset) & | |
3632 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3633 | ||
d397712b | 3634 | while (len > 0) { |
d1310b2e CM |
3635 | page = extent_buffer_page(dst, i); |
3636 | WARN_ON(!PageUptodate(page)); | |
3637 | ||
3638 | cur = min(len, (unsigned long)(PAGE_CACHE_SIZE - offset)); | |
3639 | ||
3640 | kaddr = kmap_atomic(page, KM_USER0); | |
3641 | read_extent_buffer(src, kaddr + offset, src_offset, cur); | |
3642 | kunmap_atomic(kaddr, KM_USER0); | |
3643 | ||
3644 | src_offset += cur; | |
3645 | len -= cur; | |
3646 | offset = 0; | |
3647 | i++; | |
3648 | } | |
3649 | } | |
d1310b2e CM |
3650 | |
3651 | static void move_pages(struct page *dst_page, struct page *src_page, | |
3652 | unsigned long dst_off, unsigned long src_off, | |
3653 | unsigned long len) | |
3654 | { | |
3655 | char *dst_kaddr = kmap_atomic(dst_page, KM_USER0); | |
3656 | if (dst_page == src_page) { | |
3657 | memmove(dst_kaddr + dst_off, dst_kaddr + src_off, len); | |
3658 | } else { | |
3659 | char *src_kaddr = kmap_atomic(src_page, KM_USER1); | |
3660 | char *p = dst_kaddr + dst_off + len; | |
3661 | char *s = src_kaddr + src_off + len; | |
3662 | ||
3663 | while (len--) | |
3664 | *--p = *--s; | |
3665 | ||
3666 | kunmap_atomic(src_kaddr, KM_USER1); | |
3667 | } | |
3668 | kunmap_atomic(dst_kaddr, KM_USER0); | |
3669 | } | |
3670 | ||
3671 | static void copy_pages(struct page *dst_page, struct page *src_page, | |
3672 | unsigned long dst_off, unsigned long src_off, | |
3673 | unsigned long len) | |
3674 | { | |
3675 | char *dst_kaddr = kmap_atomic(dst_page, KM_USER0); | |
3676 | char *src_kaddr; | |
3677 | ||
3678 | if (dst_page != src_page) | |
3679 | src_kaddr = kmap_atomic(src_page, KM_USER1); | |
3680 | else | |
3681 | src_kaddr = dst_kaddr; | |
3682 | ||
3683 | memcpy(dst_kaddr + dst_off, src_kaddr + src_off, len); | |
3684 | kunmap_atomic(dst_kaddr, KM_USER0); | |
3685 | if (dst_page != src_page) | |
3686 | kunmap_atomic(src_kaddr, KM_USER1); | |
3687 | } | |
3688 | ||
3689 | void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, | |
3690 | unsigned long src_offset, unsigned long len) | |
3691 | { | |
3692 | size_t cur; | |
3693 | size_t dst_off_in_page; | |
3694 | size_t src_off_in_page; | |
3695 | size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3696 | unsigned long dst_i; | |
3697 | unsigned long src_i; | |
3698 | ||
3699 | if (src_offset + len > dst->len) { | |
d397712b CM |
3700 | printk(KERN_ERR "btrfs memmove bogus src_offset %lu move " |
3701 | "len %lu dst len %lu\n", src_offset, len, dst->len); | |
d1310b2e CM |
3702 | BUG_ON(1); |
3703 | } | |
3704 | if (dst_offset + len > dst->len) { | |
d397712b CM |
3705 | printk(KERN_ERR "btrfs memmove bogus dst_offset %lu move " |
3706 | "len %lu dst len %lu\n", dst_offset, len, dst->len); | |
d1310b2e CM |
3707 | BUG_ON(1); |
3708 | } | |
3709 | ||
d397712b | 3710 | while (len > 0) { |
d1310b2e CM |
3711 | dst_off_in_page = (start_offset + dst_offset) & |
3712 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3713 | src_off_in_page = (start_offset + src_offset) & | |
3714 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3715 | ||
3716 | dst_i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT; | |
3717 | src_i = (start_offset + src_offset) >> PAGE_CACHE_SHIFT; | |
3718 | ||
3719 | cur = min(len, (unsigned long)(PAGE_CACHE_SIZE - | |
3720 | src_off_in_page)); | |
3721 | cur = min_t(unsigned long, cur, | |
3722 | (unsigned long)(PAGE_CACHE_SIZE - dst_off_in_page)); | |
3723 | ||
3724 | copy_pages(extent_buffer_page(dst, dst_i), | |
3725 | extent_buffer_page(dst, src_i), | |
3726 | dst_off_in_page, src_off_in_page, cur); | |
3727 | ||
3728 | src_offset += cur; | |
3729 | dst_offset += cur; | |
3730 | len -= cur; | |
3731 | } | |
3732 | } | |
d1310b2e CM |
3733 | |
3734 | void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, | |
3735 | unsigned long src_offset, unsigned long len) | |
3736 | { | |
3737 | size_t cur; | |
3738 | size_t dst_off_in_page; | |
3739 | size_t src_off_in_page; | |
3740 | unsigned long dst_end = dst_offset + len - 1; | |
3741 | unsigned long src_end = src_offset + len - 1; | |
3742 | size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3743 | unsigned long dst_i; | |
3744 | unsigned long src_i; | |
3745 | ||
3746 | if (src_offset + len > dst->len) { | |
d397712b CM |
3747 | printk(KERN_ERR "btrfs memmove bogus src_offset %lu move " |
3748 | "len %lu len %lu\n", src_offset, len, dst->len); | |
d1310b2e CM |
3749 | BUG_ON(1); |
3750 | } | |
3751 | if (dst_offset + len > dst->len) { | |
d397712b CM |
3752 | printk(KERN_ERR "btrfs memmove bogus dst_offset %lu move " |
3753 | "len %lu len %lu\n", dst_offset, len, dst->len); | |
d1310b2e CM |
3754 | BUG_ON(1); |
3755 | } | |
3756 | if (dst_offset < src_offset) { | |
3757 | memcpy_extent_buffer(dst, dst_offset, src_offset, len); | |
3758 | return; | |
3759 | } | |
d397712b | 3760 | while (len > 0) { |
d1310b2e CM |
3761 | dst_i = (start_offset + dst_end) >> PAGE_CACHE_SHIFT; |
3762 | src_i = (start_offset + src_end) >> PAGE_CACHE_SHIFT; | |
3763 | ||
3764 | dst_off_in_page = (start_offset + dst_end) & | |
3765 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3766 | src_off_in_page = (start_offset + src_end) & | |
3767 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3768 | ||
3769 | cur = min_t(unsigned long, len, src_off_in_page + 1); | |
3770 | cur = min(cur, dst_off_in_page + 1); | |
3771 | move_pages(extent_buffer_page(dst, dst_i), | |
3772 | extent_buffer_page(dst, src_i), | |
3773 | dst_off_in_page - cur + 1, | |
3774 | src_off_in_page - cur + 1, cur); | |
3775 | ||
3776 | dst_end -= cur; | |
3777 | src_end -= cur; | |
3778 | len -= cur; | |
3779 | } | |
3780 | } | |
6af118ce CM |
3781 | |
3782 | int try_release_extent_buffer(struct extent_io_tree *tree, struct page *page) | |
3783 | { | |
3784 | u64 start = page_offset(page); | |
3785 | struct extent_buffer *eb; | |
3786 | int ret = 1; | |
3787 | unsigned long i; | |
3788 | unsigned long num_pages; | |
3789 | ||
3790 | spin_lock(&tree->buffer_lock); | |
3791 | eb = buffer_search(tree, start); | |
3792 | if (!eb) | |
3793 | goto out; | |
3794 | ||
3795 | if (atomic_read(&eb->refs) > 1) { | |
3796 | ret = 0; | |
3797 | goto out; | |
3798 | } | |
3799 | /* at this point we can safely release the extent buffer */ | |
3800 | num_pages = num_extent_pages(eb->start, eb->len); | |
b214107e CH |
3801 | for (i = 0; i < num_pages; i++) |
3802 | page_cache_release(extent_buffer_page(eb, i)); | |
6af118ce CM |
3803 | rb_erase(&eb->rb_node, &tree->buffer); |
3804 | __free_extent_buffer(eb); | |
3805 | out: | |
3806 | spin_unlock(&tree->buffer_lock); | |
3807 | return ret; | |
3808 | } |