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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> | |
12 | #include <linux/version.h> | |
13 | #include <linux/writeback.h> | |
14 | #include <linux/pagevec.h> | |
15 | #include "extent_io.h" | |
16 | #include "extent_map.h" | |
2db04966 | 17 | #include "compat.h" |
902b22f3 DW |
18 | #include "ctree.h" |
19 | #include "btrfs_inode.h" | |
d1310b2e CM |
20 | |
21 | /* temporary define until extent_map moves out of btrfs */ | |
22 | struct kmem_cache *btrfs_cache_create(const char *name, size_t size, | |
23 | unsigned long extra_flags, | |
24 | void (*ctor)(void *, struct kmem_cache *, | |
25 | unsigned long)); | |
26 | ||
27 | static struct kmem_cache *extent_state_cache; | |
28 | static struct kmem_cache *extent_buffer_cache; | |
29 | ||
30 | static LIST_HEAD(buffers); | |
31 | static LIST_HEAD(states); | |
4bef0848 CM |
32 | |
33 | #ifdef LEAK_DEBUG | |
2d2ae547 | 34 | static spinlock_t leak_lock = SPIN_LOCK_UNLOCKED; |
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; | |
49 | }; | |
50 | ||
51 | int __init extent_io_init(void) | |
52 | { | |
53 | extent_state_cache = btrfs_cache_create("extent_state", | |
54 | sizeof(struct extent_state), 0, | |
55 | NULL); | |
56 | if (!extent_state_cache) | |
57 | return -ENOMEM; | |
58 | ||
59 | extent_buffer_cache = btrfs_cache_create("extent_buffers", | |
60 | sizeof(struct extent_buffer), 0, | |
61 | NULL); | |
62 | if (!extent_buffer_cache) | |
63 | goto free_state_cache; | |
64 | return 0; | |
65 | ||
66 | free_state_cache: | |
67 | kmem_cache_destroy(extent_state_cache); | |
68 | return -ENOMEM; | |
69 | } | |
70 | ||
71 | void extent_io_exit(void) | |
72 | { | |
73 | struct extent_state *state; | |
2d2ae547 | 74 | struct extent_buffer *eb; |
d1310b2e CM |
75 | |
76 | while (!list_empty(&states)) { | |
2d2ae547 | 77 | state = list_entry(states.next, struct extent_state, leak_list); |
70dec807 | 78 | printk("state leak: start %Lu end %Lu state %lu in tree %p refs %d\n", state->start, state->end, state->state, state->tree, atomic_read(&state->refs)); |
2d2ae547 | 79 | list_del(&state->leak_list); |
d1310b2e CM |
80 | kmem_cache_free(extent_state_cache, state); |
81 | ||
82 | } | |
83 | ||
2d2ae547 CM |
84 | while (!list_empty(&buffers)) { |
85 | eb = list_entry(buffers.next, struct extent_buffer, leak_list); | |
86 | printk("buffer leak start %Lu len %lu refs %d\n", eb->start, eb->len, atomic_read(&eb->refs)); | |
87 | list_del(&eb->leak_list); | |
88 | kmem_cache_free(extent_buffer_cache, eb); | |
89 | } | |
d1310b2e CM |
90 | if (extent_state_cache) |
91 | kmem_cache_destroy(extent_state_cache); | |
92 | if (extent_buffer_cache) | |
93 | kmem_cache_destroy(extent_buffer_cache); | |
94 | } | |
95 | ||
96 | void extent_io_tree_init(struct extent_io_tree *tree, | |
97 | struct address_space *mapping, gfp_t mask) | |
98 | { | |
99 | tree->state.rb_node = NULL; | |
6af118ce | 100 | tree->buffer.rb_node = NULL; |
d1310b2e CM |
101 | tree->ops = NULL; |
102 | tree->dirty_bytes = 0; | |
70dec807 | 103 | spin_lock_init(&tree->lock); |
6af118ce | 104 | spin_lock_init(&tree->buffer_lock); |
d1310b2e | 105 | tree->mapping = mapping; |
d1310b2e CM |
106 | } |
107 | EXPORT_SYMBOL(extent_io_tree_init); | |
108 | ||
d1310b2e CM |
109 | struct extent_state *alloc_extent_state(gfp_t mask) |
110 | { | |
111 | struct extent_state *state; | |
4bef0848 | 112 | #ifdef LEAK_DEBUG |
2d2ae547 | 113 | unsigned long flags; |
4bef0848 | 114 | #endif |
d1310b2e CM |
115 | |
116 | state = kmem_cache_alloc(extent_state_cache, mask); | |
2b114d1d | 117 | if (!state) |
d1310b2e CM |
118 | return state; |
119 | state->state = 0; | |
d1310b2e | 120 | state->private = 0; |
70dec807 | 121 | state->tree = NULL; |
4bef0848 | 122 | #ifdef LEAK_DEBUG |
2d2ae547 CM |
123 | spin_lock_irqsave(&leak_lock, flags); |
124 | list_add(&state->leak_list, &states); | |
125 | spin_unlock_irqrestore(&leak_lock, flags); | |
4bef0848 | 126 | #endif |
d1310b2e CM |
127 | atomic_set(&state->refs, 1); |
128 | init_waitqueue_head(&state->wq); | |
129 | return state; | |
130 | } | |
131 | EXPORT_SYMBOL(alloc_extent_state); | |
132 | ||
133 | void free_extent_state(struct extent_state *state) | |
134 | { | |
d1310b2e CM |
135 | if (!state) |
136 | return; | |
137 | if (atomic_dec_and_test(&state->refs)) { | |
4bef0848 | 138 | #ifdef LEAK_DEBUG |
2d2ae547 | 139 | unsigned long flags; |
4bef0848 | 140 | #endif |
70dec807 | 141 | WARN_ON(state->tree); |
4bef0848 | 142 | #ifdef LEAK_DEBUG |
2d2ae547 CM |
143 | spin_lock_irqsave(&leak_lock, flags); |
144 | list_del(&state->leak_list); | |
145 | spin_unlock_irqrestore(&leak_lock, flags); | |
4bef0848 | 146 | #endif |
d1310b2e CM |
147 | kmem_cache_free(extent_state_cache, state); |
148 | } | |
149 | } | |
150 | EXPORT_SYMBOL(free_extent_state); | |
151 | ||
152 | static struct rb_node *tree_insert(struct rb_root *root, u64 offset, | |
153 | struct rb_node *node) | |
154 | { | |
155 | struct rb_node ** p = &root->rb_node; | |
156 | struct rb_node * parent = NULL; | |
157 | struct tree_entry *entry; | |
158 | ||
159 | while(*p) { | |
160 | parent = *p; | |
161 | entry = rb_entry(parent, struct tree_entry, rb_node); | |
162 | ||
163 | if (offset < entry->start) | |
164 | p = &(*p)->rb_left; | |
165 | else if (offset > entry->end) | |
166 | p = &(*p)->rb_right; | |
167 | else | |
168 | return parent; | |
169 | } | |
170 | ||
171 | entry = rb_entry(node, struct tree_entry, rb_node); | |
d1310b2e CM |
172 | rb_link_node(node, parent, p); |
173 | rb_insert_color(node, root); | |
174 | return NULL; | |
175 | } | |
176 | ||
80ea96b1 | 177 | static struct rb_node *__etree_search(struct extent_io_tree *tree, u64 offset, |
d1310b2e CM |
178 | struct rb_node **prev_ret, |
179 | struct rb_node **next_ret) | |
180 | { | |
80ea96b1 | 181 | struct rb_root *root = &tree->state; |
d1310b2e CM |
182 | struct rb_node * n = root->rb_node; |
183 | struct rb_node *prev = NULL; | |
184 | struct rb_node *orig_prev = NULL; | |
185 | struct tree_entry *entry; | |
186 | struct tree_entry *prev_entry = NULL; | |
187 | ||
188 | while(n) { | |
189 | entry = rb_entry(n, struct tree_entry, rb_node); | |
190 | prev = n; | |
191 | prev_entry = entry; | |
192 | ||
193 | if (offset < entry->start) | |
194 | n = n->rb_left; | |
195 | else if (offset > entry->end) | |
196 | n = n->rb_right; | |
80ea96b1 | 197 | else { |
d1310b2e | 198 | return n; |
80ea96b1 | 199 | } |
d1310b2e CM |
200 | } |
201 | ||
202 | if (prev_ret) { | |
203 | orig_prev = prev; | |
204 | while(prev && offset > prev_entry->end) { | |
205 | prev = rb_next(prev); | |
206 | prev_entry = rb_entry(prev, struct tree_entry, rb_node); | |
207 | } | |
208 | *prev_ret = prev; | |
209 | prev = orig_prev; | |
210 | } | |
211 | ||
212 | if (next_ret) { | |
213 | prev_entry = rb_entry(prev, struct tree_entry, rb_node); | |
214 | while(prev && offset < prev_entry->start) { | |
215 | prev = rb_prev(prev); | |
216 | prev_entry = rb_entry(prev, struct tree_entry, rb_node); | |
217 | } | |
218 | *next_ret = prev; | |
219 | } | |
220 | return NULL; | |
221 | } | |
222 | ||
80ea96b1 CM |
223 | static inline struct rb_node *tree_search(struct extent_io_tree *tree, |
224 | u64 offset) | |
d1310b2e | 225 | { |
70dec807 | 226 | struct rb_node *prev = NULL; |
d1310b2e | 227 | struct rb_node *ret; |
70dec807 | 228 | |
80ea96b1 CM |
229 | ret = __etree_search(tree, offset, &prev, NULL); |
230 | if (!ret) { | |
d1310b2e | 231 | return prev; |
80ea96b1 | 232 | } |
d1310b2e CM |
233 | return ret; |
234 | } | |
235 | ||
6af118ce CM |
236 | static struct extent_buffer *buffer_tree_insert(struct extent_io_tree *tree, |
237 | u64 offset, struct rb_node *node) | |
238 | { | |
239 | struct rb_root *root = &tree->buffer; | |
240 | struct rb_node ** p = &root->rb_node; | |
241 | struct rb_node * parent = NULL; | |
242 | struct extent_buffer *eb; | |
243 | ||
244 | while(*p) { | |
245 | parent = *p; | |
246 | eb = rb_entry(parent, struct extent_buffer, rb_node); | |
247 | ||
248 | if (offset < eb->start) | |
249 | p = &(*p)->rb_left; | |
250 | else if (offset > eb->start) | |
251 | p = &(*p)->rb_right; | |
252 | else | |
253 | return eb; | |
254 | } | |
255 | ||
256 | rb_link_node(node, parent, p); | |
257 | rb_insert_color(node, root); | |
258 | return NULL; | |
259 | } | |
260 | ||
261 | static struct extent_buffer *buffer_search(struct extent_io_tree *tree, | |
262 | u64 offset) | |
263 | { | |
264 | struct rb_root *root = &tree->buffer; | |
265 | struct rb_node * n = root->rb_node; | |
266 | struct extent_buffer *eb; | |
267 | ||
268 | while(n) { | |
269 | eb = rb_entry(n, struct extent_buffer, rb_node); | |
270 | if (offset < eb->start) | |
271 | n = n->rb_left; | |
272 | else if (offset > eb->start) | |
273 | n = n->rb_right; | |
274 | else | |
275 | return eb; | |
276 | } | |
277 | return NULL; | |
278 | } | |
279 | ||
d1310b2e CM |
280 | /* |
281 | * utility function to look for merge candidates inside a given range. | |
282 | * Any extents with matching state are merged together into a single | |
283 | * extent in the tree. Extents with EXTENT_IO in their state field | |
284 | * are not merged because the end_io handlers need to be able to do | |
285 | * operations on them without sleeping (or doing allocations/splits). | |
286 | * | |
287 | * This should be called with the tree lock held. | |
288 | */ | |
289 | static int merge_state(struct extent_io_tree *tree, | |
290 | struct extent_state *state) | |
291 | { | |
292 | struct extent_state *other; | |
293 | struct rb_node *other_node; | |
294 | ||
5b21f2ed | 295 | if (state->state & (EXTENT_IOBITS | EXTENT_BOUNDARY)) |
d1310b2e CM |
296 | return 0; |
297 | ||
298 | other_node = rb_prev(&state->rb_node); | |
299 | if (other_node) { | |
300 | other = rb_entry(other_node, struct extent_state, rb_node); | |
301 | if (other->end == state->start - 1 && | |
302 | other->state == state->state) { | |
303 | state->start = other->start; | |
70dec807 | 304 | other->tree = NULL; |
d1310b2e CM |
305 | rb_erase(&other->rb_node, &tree->state); |
306 | free_extent_state(other); | |
307 | } | |
308 | } | |
309 | other_node = rb_next(&state->rb_node); | |
310 | if (other_node) { | |
311 | other = rb_entry(other_node, struct extent_state, rb_node); | |
312 | if (other->start == state->end + 1 && | |
313 | other->state == state->state) { | |
314 | other->start = state->start; | |
70dec807 | 315 | state->tree = NULL; |
d1310b2e CM |
316 | rb_erase(&state->rb_node, &tree->state); |
317 | free_extent_state(state); | |
318 | } | |
319 | } | |
320 | return 0; | |
321 | } | |
322 | ||
291d673e CM |
323 | static void set_state_cb(struct extent_io_tree *tree, |
324 | struct extent_state *state, | |
325 | unsigned long bits) | |
326 | { | |
327 | if (tree->ops && tree->ops->set_bit_hook) { | |
328 | tree->ops->set_bit_hook(tree->mapping->host, state->start, | |
b0c68f8b | 329 | state->end, state->state, bits); |
291d673e CM |
330 | } |
331 | } | |
332 | ||
333 | static void clear_state_cb(struct extent_io_tree *tree, | |
334 | struct extent_state *state, | |
335 | unsigned long bits) | |
336 | { | |
337 | if (tree->ops && tree->ops->set_bit_hook) { | |
338 | tree->ops->clear_bit_hook(tree->mapping->host, state->start, | |
b0c68f8b | 339 | state->end, state->state, bits); |
291d673e CM |
340 | } |
341 | } | |
342 | ||
d1310b2e CM |
343 | /* |
344 | * insert an extent_state struct into the tree. 'bits' are set on the | |
345 | * struct before it is inserted. | |
346 | * | |
347 | * This may return -EEXIST if the extent is already there, in which case the | |
348 | * state struct is freed. | |
349 | * | |
350 | * The tree lock is not taken internally. This is a utility function and | |
351 | * probably isn't what you want to call (see set/clear_extent_bit). | |
352 | */ | |
353 | static int insert_state(struct extent_io_tree *tree, | |
354 | struct extent_state *state, u64 start, u64 end, | |
355 | int bits) | |
356 | { | |
357 | struct rb_node *node; | |
358 | ||
359 | if (end < start) { | |
360 | printk("end < start %Lu %Lu\n", end, start); | |
361 | WARN_ON(1); | |
362 | } | |
363 | if (bits & EXTENT_DIRTY) | |
364 | tree->dirty_bytes += end - start + 1; | |
b0c68f8b | 365 | set_state_cb(tree, state, bits); |
d1310b2e CM |
366 | state->state |= bits; |
367 | state->start = start; | |
368 | state->end = end; | |
369 | node = tree_insert(&tree->state, end, &state->rb_node); | |
370 | if (node) { | |
371 | struct extent_state *found; | |
372 | found = rb_entry(node, struct extent_state, rb_node); | |
373 | printk("found node %Lu %Lu on insert of %Lu %Lu\n", found->start, found->end, start, end); | |
374 | free_extent_state(state); | |
375 | return -EEXIST; | |
376 | } | |
70dec807 | 377 | state->tree = tree; |
d1310b2e CM |
378 | merge_state(tree, state); |
379 | return 0; | |
380 | } | |
381 | ||
382 | /* | |
383 | * split a given extent state struct in two, inserting the preallocated | |
384 | * struct 'prealloc' as the newly created second half. 'split' indicates an | |
385 | * offset inside 'orig' where it should be split. | |
386 | * | |
387 | * Before calling, | |
388 | * the tree has 'orig' at [orig->start, orig->end]. After calling, there | |
389 | * are two extent state structs in the tree: | |
390 | * prealloc: [orig->start, split - 1] | |
391 | * orig: [ split, orig->end ] | |
392 | * | |
393 | * The tree locks are not taken by this function. They need to be held | |
394 | * by the caller. | |
395 | */ | |
396 | static int split_state(struct extent_io_tree *tree, struct extent_state *orig, | |
397 | struct extent_state *prealloc, u64 split) | |
398 | { | |
399 | struct rb_node *node; | |
400 | prealloc->start = orig->start; | |
401 | prealloc->end = split - 1; | |
402 | prealloc->state = orig->state; | |
403 | orig->start = split; | |
404 | ||
405 | node = tree_insert(&tree->state, prealloc->end, &prealloc->rb_node); | |
406 | if (node) { | |
407 | struct extent_state *found; | |
408 | found = rb_entry(node, struct extent_state, rb_node); | |
409 | printk("found node %Lu %Lu on insert of %Lu %Lu\n", found->start, found->end, prealloc->start, prealloc->end); | |
410 | free_extent_state(prealloc); | |
411 | return -EEXIST; | |
412 | } | |
70dec807 | 413 | prealloc->tree = tree; |
d1310b2e CM |
414 | return 0; |
415 | } | |
416 | ||
417 | /* | |
418 | * utility function to clear some bits in an extent state struct. | |
419 | * it will optionally wake up any one waiting on this state (wake == 1), or | |
420 | * forcibly remove the state from the tree (delete == 1). | |
421 | * | |
422 | * If no bits are set on the state struct after clearing things, the | |
423 | * struct is freed and removed from the tree | |
424 | */ | |
425 | static int clear_state_bit(struct extent_io_tree *tree, | |
426 | struct extent_state *state, int bits, int wake, | |
427 | int delete) | |
428 | { | |
429 | int ret = state->state & bits; | |
430 | ||
431 | if ((bits & EXTENT_DIRTY) && (state->state & EXTENT_DIRTY)) { | |
432 | u64 range = state->end - state->start + 1; | |
433 | WARN_ON(range > tree->dirty_bytes); | |
434 | tree->dirty_bytes -= range; | |
435 | } | |
291d673e | 436 | clear_state_cb(tree, state, bits); |
b0c68f8b | 437 | state->state &= ~bits; |
d1310b2e CM |
438 | if (wake) |
439 | wake_up(&state->wq); | |
440 | if (delete || state->state == 0) { | |
70dec807 | 441 | if (state->tree) { |
ae9d1285 | 442 | clear_state_cb(tree, state, state->state); |
d1310b2e | 443 | rb_erase(&state->rb_node, &tree->state); |
70dec807 | 444 | state->tree = NULL; |
d1310b2e CM |
445 | free_extent_state(state); |
446 | } else { | |
447 | WARN_ON(1); | |
448 | } | |
449 | } else { | |
450 | merge_state(tree, state); | |
451 | } | |
452 | return ret; | |
453 | } | |
454 | ||
455 | /* | |
456 | * clear some bits on a range in the tree. This may require splitting | |
457 | * or inserting elements in the tree, so the gfp mask is used to | |
458 | * indicate which allocations or sleeping are allowed. | |
459 | * | |
460 | * pass 'wake' == 1 to kick any sleepers, and 'delete' == 1 to remove | |
461 | * the given range from the tree regardless of state (ie for truncate). | |
462 | * | |
463 | * the range [start, end] is inclusive. | |
464 | * | |
465 | * This takes the tree lock, and returns < 0 on error, > 0 if any of the | |
466 | * bits were already set, or zero if none of the bits were already set. | |
467 | */ | |
468 | int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, | |
469 | int bits, int wake, int delete, gfp_t mask) | |
470 | { | |
471 | struct extent_state *state; | |
472 | struct extent_state *prealloc = NULL; | |
473 | struct rb_node *node; | |
474 | unsigned long flags; | |
475 | int err; | |
476 | int set = 0; | |
477 | ||
478 | again: | |
479 | if (!prealloc && (mask & __GFP_WAIT)) { | |
480 | prealloc = alloc_extent_state(mask); | |
481 | if (!prealloc) | |
482 | return -ENOMEM; | |
483 | } | |
484 | ||
70dec807 | 485 | spin_lock_irqsave(&tree->lock, flags); |
d1310b2e CM |
486 | /* |
487 | * this search will find the extents that end after | |
488 | * our range starts | |
489 | */ | |
80ea96b1 | 490 | node = tree_search(tree, start); |
d1310b2e CM |
491 | if (!node) |
492 | goto out; | |
493 | state = rb_entry(node, struct extent_state, rb_node); | |
494 | if (state->start > end) | |
495 | goto out; | |
496 | WARN_ON(state->end < start); | |
497 | ||
498 | /* | |
499 | * | ---- desired range ---- | | |
500 | * | state | or | |
501 | * | ------------- state -------------- | | |
502 | * | |
503 | * We need to split the extent we found, and may flip | |
504 | * bits on second half. | |
505 | * | |
506 | * If the extent we found extends past our range, we | |
507 | * just split and search again. It'll get split again | |
508 | * the next time though. | |
509 | * | |
510 | * If the extent we found is inside our range, we clear | |
511 | * the desired bit on it. | |
512 | */ | |
513 | ||
514 | if (state->start < start) { | |
70dec807 CM |
515 | if (!prealloc) |
516 | prealloc = alloc_extent_state(GFP_ATOMIC); | |
d1310b2e CM |
517 | err = split_state(tree, state, prealloc, start); |
518 | BUG_ON(err == -EEXIST); | |
519 | prealloc = NULL; | |
520 | if (err) | |
521 | goto out; | |
522 | if (state->end <= end) { | |
523 | start = state->end + 1; | |
524 | set |= clear_state_bit(tree, state, bits, | |
525 | wake, delete); | |
526 | } else { | |
527 | start = state->start; | |
528 | } | |
529 | goto search_again; | |
530 | } | |
531 | /* | |
532 | * | ---- desired range ---- | | |
533 | * | state | | |
534 | * We need to split the extent, and clear the bit | |
535 | * on the first half | |
536 | */ | |
537 | if (state->start <= end && state->end > end) { | |
70dec807 CM |
538 | if (!prealloc) |
539 | prealloc = alloc_extent_state(GFP_ATOMIC); | |
d1310b2e CM |
540 | err = split_state(tree, state, prealloc, end + 1); |
541 | BUG_ON(err == -EEXIST); | |
542 | ||
543 | if (wake) | |
544 | wake_up(&state->wq); | |
545 | set |= clear_state_bit(tree, prealloc, bits, | |
546 | wake, delete); | |
547 | prealloc = NULL; | |
548 | goto out; | |
549 | } | |
550 | ||
551 | start = state->end + 1; | |
552 | set |= clear_state_bit(tree, state, bits, wake, delete); | |
553 | goto search_again; | |
554 | ||
555 | out: | |
70dec807 | 556 | spin_unlock_irqrestore(&tree->lock, flags); |
d1310b2e CM |
557 | if (prealloc) |
558 | free_extent_state(prealloc); | |
559 | ||
560 | return set; | |
561 | ||
562 | search_again: | |
563 | if (start > end) | |
564 | goto out; | |
70dec807 | 565 | spin_unlock_irqrestore(&tree->lock, flags); |
d1310b2e CM |
566 | if (mask & __GFP_WAIT) |
567 | cond_resched(); | |
568 | goto again; | |
569 | } | |
570 | EXPORT_SYMBOL(clear_extent_bit); | |
571 | ||
572 | static int wait_on_state(struct extent_io_tree *tree, | |
573 | struct extent_state *state) | |
574 | { | |
575 | DEFINE_WAIT(wait); | |
576 | prepare_to_wait(&state->wq, &wait, TASK_UNINTERRUPTIBLE); | |
70dec807 | 577 | spin_unlock_irq(&tree->lock); |
d1310b2e | 578 | schedule(); |
70dec807 | 579 | spin_lock_irq(&tree->lock); |
d1310b2e CM |
580 | finish_wait(&state->wq, &wait); |
581 | return 0; | |
582 | } | |
583 | ||
584 | /* | |
585 | * waits for one or more bits to clear on a range in the state tree. | |
586 | * The range [start, end] is inclusive. | |
587 | * The tree lock is taken by this function | |
588 | */ | |
589 | int wait_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, int bits) | |
590 | { | |
591 | struct extent_state *state; | |
592 | struct rb_node *node; | |
593 | ||
70dec807 | 594 | spin_lock_irq(&tree->lock); |
d1310b2e CM |
595 | again: |
596 | while (1) { | |
597 | /* | |
598 | * this search will find all the extents that end after | |
599 | * our range starts | |
600 | */ | |
80ea96b1 | 601 | node = tree_search(tree, start); |
d1310b2e CM |
602 | if (!node) |
603 | break; | |
604 | ||
605 | state = rb_entry(node, struct extent_state, rb_node); | |
606 | ||
607 | if (state->start > end) | |
608 | goto out; | |
609 | ||
610 | if (state->state & bits) { | |
611 | start = state->start; | |
612 | atomic_inc(&state->refs); | |
613 | wait_on_state(tree, state); | |
614 | free_extent_state(state); | |
615 | goto again; | |
616 | } | |
617 | start = state->end + 1; | |
618 | ||
619 | if (start > end) | |
620 | break; | |
621 | ||
622 | if (need_resched()) { | |
70dec807 | 623 | spin_unlock_irq(&tree->lock); |
d1310b2e | 624 | cond_resched(); |
70dec807 | 625 | spin_lock_irq(&tree->lock); |
d1310b2e CM |
626 | } |
627 | } | |
628 | out: | |
70dec807 | 629 | spin_unlock_irq(&tree->lock); |
d1310b2e CM |
630 | return 0; |
631 | } | |
632 | EXPORT_SYMBOL(wait_extent_bit); | |
633 | ||
634 | static void set_state_bits(struct extent_io_tree *tree, | |
635 | struct extent_state *state, | |
636 | int bits) | |
637 | { | |
638 | if ((bits & EXTENT_DIRTY) && !(state->state & EXTENT_DIRTY)) { | |
639 | u64 range = state->end - state->start + 1; | |
640 | tree->dirty_bytes += range; | |
641 | } | |
291d673e | 642 | set_state_cb(tree, state, bits); |
b0c68f8b | 643 | state->state |= bits; |
d1310b2e CM |
644 | } |
645 | ||
646 | /* | |
647 | * set some bits on a range in the tree. This may require allocations | |
648 | * or sleeping, so the gfp mask is used to indicate what is allowed. | |
649 | * | |
650 | * If 'exclusive' == 1, this will fail with -EEXIST if some part of the | |
651 | * range already has the desired bits set. The start of the existing | |
652 | * range is returned in failed_start in this case. | |
653 | * | |
654 | * [start, end] is inclusive | |
655 | * This takes the tree lock. | |
656 | */ | |
657 | int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, int bits, | |
658 | int exclusive, u64 *failed_start, gfp_t mask) | |
659 | { | |
660 | struct extent_state *state; | |
661 | struct extent_state *prealloc = NULL; | |
662 | struct rb_node *node; | |
663 | unsigned long flags; | |
664 | int err = 0; | |
665 | int set; | |
666 | u64 last_start; | |
667 | u64 last_end; | |
668 | again: | |
669 | if (!prealloc && (mask & __GFP_WAIT)) { | |
670 | prealloc = alloc_extent_state(mask); | |
671 | if (!prealloc) | |
672 | return -ENOMEM; | |
673 | } | |
674 | ||
70dec807 | 675 | spin_lock_irqsave(&tree->lock, flags); |
d1310b2e CM |
676 | /* |
677 | * this search will find all the extents that end after | |
678 | * our range starts. | |
679 | */ | |
80ea96b1 | 680 | node = tree_search(tree, start); |
d1310b2e CM |
681 | if (!node) { |
682 | err = insert_state(tree, prealloc, start, end, bits); | |
683 | prealloc = NULL; | |
684 | BUG_ON(err == -EEXIST); | |
685 | goto out; | |
686 | } | |
687 | ||
688 | state = rb_entry(node, struct extent_state, rb_node); | |
689 | last_start = state->start; | |
690 | last_end = state->end; | |
691 | ||
692 | /* | |
693 | * | ---- desired range ---- | | |
694 | * | state | | |
695 | * | |
696 | * Just lock what we found and keep going | |
697 | */ | |
698 | if (state->start == start && state->end <= end) { | |
699 | set = state->state & bits; | |
700 | if (set && exclusive) { | |
701 | *failed_start = state->start; | |
702 | err = -EEXIST; | |
703 | goto out; | |
704 | } | |
705 | set_state_bits(tree, state, bits); | |
706 | start = state->end + 1; | |
707 | merge_state(tree, state); | |
708 | goto search_again; | |
709 | } | |
710 | ||
711 | /* | |
712 | * | ---- desired range ---- | | |
713 | * | state | | |
714 | * or | |
715 | * | ------------- state -------------- | | |
716 | * | |
717 | * We need to split the extent we found, and may flip bits on | |
718 | * second half. | |
719 | * | |
720 | * If the extent we found extends past our | |
721 | * range, we just split and search again. It'll get split | |
722 | * again the next time though. | |
723 | * | |
724 | * If the extent we found is inside our range, we set the | |
725 | * desired bit on it. | |
726 | */ | |
727 | if (state->start < start) { | |
728 | set = state->state & bits; | |
729 | if (exclusive && set) { | |
730 | *failed_start = start; | |
731 | err = -EEXIST; | |
732 | goto out; | |
733 | } | |
734 | err = split_state(tree, state, prealloc, start); | |
735 | BUG_ON(err == -EEXIST); | |
736 | prealloc = NULL; | |
737 | if (err) | |
738 | goto out; | |
739 | if (state->end <= end) { | |
740 | set_state_bits(tree, state, bits); | |
741 | start = state->end + 1; | |
742 | merge_state(tree, state); | |
743 | } else { | |
744 | start = state->start; | |
745 | } | |
746 | goto search_again; | |
747 | } | |
748 | /* | |
749 | * | ---- desired range ---- | | |
750 | * | state | or | state | | |
751 | * | |
752 | * There's a hole, we need to insert something in it and | |
753 | * ignore the extent we found. | |
754 | */ | |
755 | if (state->start > start) { | |
756 | u64 this_end; | |
757 | if (end < last_start) | |
758 | this_end = end; | |
759 | else | |
760 | this_end = last_start -1; | |
761 | err = insert_state(tree, prealloc, start, this_end, | |
762 | bits); | |
763 | prealloc = NULL; | |
764 | BUG_ON(err == -EEXIST); | |
765 | if (err) | |
766 | goto out; | |
767 | start = this_end + 1; | |
768 | goto search_again; | |
769 | } | |
770 | /* | |
771 | * | ---- desired range ---- | | |
772 | * | state | | |
773 | * We need to split the extent, and set the bit | |
774 | * on the first half | |
775 | */ | |
776 | if (state->start <= end && state->end > end) { | |
777 | set = state->state & bits; | |
778 | if (exclusive && set) { | |
779 | *failed_start = start; | |
780 | err = -EEXIST; | |
781 | goto out; | |
782 | } | |
783 | err = split_state(tree, state, prealloc, end + 1); | |
784 | BUG_ON(err == -EEXIST); | |
785 | ||
786 | set_state_bits(tree, prealloc, bits); | |
787 | merge_state(tree, prealloc); | |
788 | prealloc = NULL; | |
789 | goto out; | |
790 | } | |
791 | ||
792 | goto search_again; | |
793 | ||
794 | out: | |
70dec807 | 795 | spin_unlock_irqrestore(&tree->lock, flags); |
d1310b2e CM |
796 | if (prealloc) |
797 | free_extent_state(prealloc); | |
798 | ||
799 | return err; | |
800 | ||
801 | search_again: | |
802 | if (start > end) | |
803 | goto out; | |
70dec807 | 804 | spin_unlock_irqrestore(&tree->lock, flags); |
d1310b2e CM |
805 | if (mask & __GFP_WAIT) |
806 | cond_resched(); | |
807 | goto again; | |
808 | } | |
809 | EXPORT_SYMBOL(set_extent_bit); | |
810 | ||
811 | /* wrappers around set/clear extent bit */ | |
812 | int set_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end, | |
813 | gfp_t mask) | |
814 | { | |
815 | return set_extent_bit(tree, start, end, EXTENT_DIRTY, 0, NULL, | |
816 | mask); | |
817 | } | |
818 | EXPORT_SYMBOL(set_extent_dirty); | |
819 | ||
e6dcd2dc CM |
820 | int set_extent_ordered(struct extent_io_tree *tree, u64 start, u64 end, |
821 | gfp_t mask) | |
822 | { | |
823 | return set_extent_bit(tree, start, end, EXTENT_ORDERED, 0, NULL, mask); | |
824 | } | |
825 | EXPORT_SYMBOL(set_extent_ordered); | |
826 | ||
d1310b2e CM |
827 | int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, |
828 | int bits, gfp_t mask) | |
829 | { | |
830 | return set_extent_bit(tree, start, end, bits, 0, NULL, | |
831 | mask); | |
832 | } | |
833 | EXPORT_SYMBOL(set_extent_bits); | |
834 | ||
835 | int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, | |
836 | int bits, gfp_t mask) | |
837 | { | |
838 | return clear_extent_bit(tree, start, end, bits, 0, 0, mask); | |
839 | } | |
840 | EXPORT_SYMBOL(clear_extent_bits); | |
841 | ||
842 | int set_extent_delalloc(struct extent_io_tree *tree, u64 start, u64 end, | |
843 | gfp_t mask) | |
844 | { | |
845 | return set_extent_bit(tree, start, end, | |
e6dcd2dc CM |
846 | EXTENT_DELALLOC | EXTENT_DIRTY, |
847 | 0, NULL, mask); | |
d1310b2e CM |
848 | } |
849 | EXPORT_SYMBOL(set_extent_delalloc); | |
850 | ||
851 | int clear_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end, | |
852 | gfp_t mask) | |
853 | { | |
854 | return clear_extent_bit(tree, start, end, | |
855 | EXTENT_DIRTY | EXTENT_DELALLOC, 0, 0, mask); | |
856 | } | |
857 | EXPORT_SYMBOL(clear_extent_dirty); | |
858 | ||
e6dcd2dc CM |
859 | int clear_extent_ordered(struct extent_io_tree *tree, u64 start, u64 end, |
860 | gfp_t mask) | |
861 | { | |
862 | return clear_extent_bit(tree, start, end, EXTENT_ORDERED, 1, 0, mask); | |
863 | } | |
864 | EXPORT_SYMBOL(clear_extent_ordered); | |
865 | ||
d1310b2e CM |
866 | int set_extent_new(struct extent_io_tree *tree, u64 start, u64 end, |
867 | gfp_t mask) | |
868 | { | |
869 | return set_extent_bit(tree, start, end, EXTENT_NEW, 0, NULL, | |
870 | mask); | |
871 | } | |
872 | EXPORT_SYMBOL(set_extent_new); | |
873 | ||
874 | int clear_extent_new(struct extent_io_tree *tree, u64 start, u64 end, | |
875 | gfp_t mask) | |
876 | { | |
877 | return clear_extent_bit(tree, start, end, EXTENT_NEW, 0, 0, mask); | |
878 | } | |
879 | EXPORT_SYMBOL(clear_extent_new); | |
880 | ||
881 | int set_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end, | |
882 | gfp_t mask) | |
883 | { | |
884 | return set_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, NULL, | |
885 | mask); | |
886 | } | |
887 | EXPORT_SYMBOL(set_extent_uptodate); | |
888 | ||
889 | int clear_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end, | |
890 | gfp_t mask) | |
891 | { | |
892 | return clear_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, 0, mask); | |
893 | } | |
894 | EXPORT_SYMBOL(clear_extent_uptodate); | |
895 | ||
896 | int set_extent_writeback(struct extent_io_tree *tree, u64 start, u64 end, | |
897 | gfp_t mask) | |
898 | { | |
899 | return set_extent_bit(tree, start, end, EXTENT_WRITEBACK, | |
900 | 0, NULL, mask); | |
901 | } | |
902 | EXPORT_SYMBOL(set_extent_writeback); | |
903 | ||
904 | int clear_extent_writeback(struct extent_io_tree *tree, u64 start, u64 end, | |
905 | gfp_t mask) | |
906 | { | |
907 | return clear_extent_bit(tree, start, end, EXTENT_WRITEBACK, 1, 0, mask); | |
908 | } | |
909 | EXPORT_SYMBOL(clear_extent_writeback); | |
910 | ||
911 | int wait_on_extent_writeback(struct extent_io_tree *tree, u64 start, u64 end) | |
912 | { | |
913 | return wait_extent_bit(tree, start, end, EXTENT_WRITEBACK); | |
914 | } | |
915 | EXPORT_SYMBOL(wait_on_extent_writeback); | |
916 | ||
d1310b2e CM |
917 | int lock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask) |
918 | { | |
919 | int err; | |
920 | u64 failed_start; | |
921 | while (1) { | |
922 | err = set_extent_bit(tree, start, end, EXTENT_LOCKED, 1, | |
923 | &failed_start, mask); | |
924 | if (err == -EEXIST && (mask & __GFP_WAIT)) { | |
925 | wait_extent_bit(tree, failed_start, end, EXTENT_LOCKED); | |
926 | start = failed_start; | |
927 | } else { | |
928 | break; | |
929 | } | |
930 | WARN_ON(start > end); | |
931 | } | |
932 | return err; | |
933 | } | |
934 | EXPORT_SYMBOL(lock_extent); | |
935 | ||
936 | int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end, | |
937 | gfp_t mask) | |
938 | { | |
939 | return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, mask); | |
940 | } | |
941 | EXPORT_SYMBOL(unlock_extent); | |
942 | ||
943 | /* | |
944 | * helper function to set pages and extents in the tree dirty | |
945 | */ | |
946 | int set_range_dirty(struct extent_io_tree *tree, u64 start, u64 end) | |
947 | { | |
948 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
949 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
950 | struct page *page; | |
951 | ||
952 | while (index <= end_index) { | |
953 | page = find_get_page(tree->mapping, index); | |
954 | BUG_ON(!page); | |
955 | __set_page_dirty_nobuffers(page); | |
956 | page_cache_release(page); | |
957 | index++; | |
958 | } | |
959 | set_extent_dirty(tree, start, end, GFP_NOFS); | |
960 | return 0; | |
961 | } | |
962 | EXPORT_SYMBOL(set_range_dirty); | |
963 | ||
964 | /* | |
965 | * helper function to set both pages and extents in the tree writeback | |
966 | */ | |
967 | int set_range_writeback(struct extent_io_tree *tree, u64 start, u64 end) | |
968 | { | |
969 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
970 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
971 | struct page *page; | |
972 | ||
973 | while (index <= end_index) { | |
974 | page = find_get_page(tree->mapping, index); | |
975 | BUG_ON(!page); | |
976 | set_page_writeback(page); | |
977 | page_cache_release(page); | |
978 | index++; | |
979 | } | |
980 | set_extent_writeback(tree, start, end, GFP_NOFS); | |
981 | return 0; | |
982 | } | |
983 | EXPORT_SYMBOL(set_range_writeback); | |
984 | ||
985 | int find_first_extent_bit(struct extent_io_tree *tree, u64 start, | |
986 | u64 *start_ret, u64 *end_ret, int bits) | |
987 | { | |
988 | struct rb_node *node; | |
989 | struct extent_state *state; | |
990 | int ret = 1; | |
991 | ||
70dec807 | 992 | spin_lock_irq(&tree->lock); |
d1310b2e CM |
993 | /* |
994 | * this search will find all the extents that end after | |
995 | * our range starts. | |
996 | */ | |
80ea96b1 | 997 | node = tree_search(tree, start); |
2b114d1d | 998 | if (!node) { |
d1310b2e CM |
999 | goto out; |
1000 | } | |
1001 | ||
1002 | while(1) { | |
1003 | state = rb_entry(node, struct extent_state, rb_node); | |
1004 | if (state->end >= start && (state->state & bits)) { | |
1005 | *start_ret = state->start; | |
1006 | *end_ret = state->end; | |
1007 | ret = 0; | |
1008 | break; | |
1009 | } | |
1010 | node = rb_next(node); | |
1011 | if (!node) | |
1012 | break; | |
1013 | } | |
1014 | out: | |
70dec807 | 1015 | spin_unlock_irq(&tree->lock); |
d1310b2e CM |
1016 | return ret; |
1017 | } | |
1018 | EXPORT_SYMBOL(find_first_extent_bit); | |
1019 | ||
d7fc640e CM |
1020 | struct extent_state *find_first_extent_bit_state(struct extent_io_tree *tree, |
1021 | u64 start, int bits) | |
1022 | { | |
1023 | struct rb_node *node; | |
1024 | struct extent_state *state; | |
1025 | ||
1026 | /* | |
1027 | * this search will find all the extents that end after | |
1028 | * our range starts. | |
1029 | */ | |
1030 | node = tree_search(tree, start); | |
2b114d1d | 1031 | if (!node) { |
d7fc640e CM |
1032 | goto out; |
1033 | } | |
1034 | ||
1035 | while(1) { | |
1036 | state = rb_entry(node, struct extent_state, rb_node); | |
1037 | if (state->end >= start && (state->state & bits)) { | |
1038 | return state; | |
1039 | } | |
1040 | node = rb_next(node); | |
1041 | if (!node) | |
1042 | break; | |
1043 | } | |
1044 | out: | |
1045 | return NULL; | |
1046 | } | |
1047 | EXPORT_SYMBOL(find_first_extent_bit_state); | |
1048 | ||
d1310b2e CM |
1049 | u64 find_lock_delalloc_range(struct extent_io_tree *tree, |
1050 | u64 *start, u64 *end, u64 max_bytes) | |
1051 | { | |
1052 | struct rb_node *node; | |
1053 | struct extent_state *state; | |
1054 | u64 cur_start = *start; | |
1055 | u64 found = 0; | |
1056 | u64 total_bytes = 0; | |
1057 | ||
70dec807 | 1058 | spin_lock_irq(&tree->lock); |
d1310b2e CM |
1059 | /* |
1060 | * this search will find all the extents that end after | |
1061 | * our range starts. | |
1062 | */ | |
1063 | search_again: | |
80ea96b1 | 1064 | node = tree_search(tree, cur_start); |
2b114d1d | 1065 | if (!node) { |
3b951516 CM |
1066 | if (!found) |
1067 | *end = (u64)-1; | |
d1310b2e CM |
1068 | goto out; |
1069 | } | |
1070 | ||
1071 | while(1) { | |
1072 | state = rb_entry(node, struct extent_state, rb_node); | |
5b21f2ed ZY |
1073 | if (found && (state->start != cur_start || |
1074 | (state->state & EXTENT_BOUNDARY))) { | |
d1310b2e CM |
1075 | goto out; |
1076 | } | |
1077 | if (!(state->state & EXTENT_DELALLOC)) { | |
1078 | if (!found) | |
1079 | *end = state->end; | |
1080 | goto out; | |
1081 | } | |
5b21f2ed | 1082 | if (!found && !(state->state & EXTENT_BOUNDARY)) { |
d1310b2e CM |
1083 | struct extent_state *prev_state; |
1084 | struct rb_node *prev_node = node; | |
1085 | while(1) { | |
1086 | prev_node = rb_prev(prev_node); | |
1087 | if (!prev_node) | |
1088 | break; | |
1089 | prev_state = rb_entry(prev_node, | |
1090 | struct extent_state, | |
1091 | rb_node); | |
5b21f2ed ZY |
1092 | if ((prev_state->end + 1 != state->start) || |
1093 | !(prev_state->state & EXTENT_DELALLOC)) | |
1094 | break; | |
1095 | if ((cur_start - prev_state->start) * 2 > | |
1096 | max_bytes) | |
d1310b2e CM |
1097 | break; |
1098 | state = prev_state; | |
1099 | node = prev_node; | |
1100 | } | |
1101 | } | |
1102 | if (state->state & EXTENT_LOCKED) { | |
1103 | DEFINE_WAIT(wait); | |
1104 | atomic_inc(&state->refs); | |
1105 | prepare_to_wait(&state->wq, &wait, | |
1106 | TASK_UNINTERRUPTIBLE); | |
70dec807 | 1107 | spin_unlock_irq(&tree->lock); |
d1310b2e | 1108 | schedule(); |
70dec807 | 1109 | spin_lock_irq(&tree->lock); |
d1310b2e CM |
1110 | finish_wait(&state->wq, &wait); |
1111 | free_extent_state(state); | |
1112 | goto search_again; | |
1113 | } | |
291d673e | 1114 | set_state_cb(tree, state, EXTENT_LOCKED); |
b0c68f8b | 1115 | state->state |= EXTENT_LOCKED; |
d1310b2e CM |
1116 | if (!found) |
1117 | *start = state->start; | |
1118 | found++; | |
1119 | *end = state->end; | |
1120 | cur_start = state->end + 1; | |
1121 | node = rb_next(node); | |
1122 | if (!node) | |
1123 | break; | |
1124 | total_bytes += state->end - state->start + 1; | |
1125 | if (total_bytes >= max_bytes) | |
1126 | break; | |
1127 | } | |
1128 | out: | |
70dec807 | 1129 | spin_unlock_irq(&tree->lock); |
d1310b2e CM |
1130 | return found; |
1131 | } | |
1132 | ||
1133 | u64 count_range_bits(struct extent_io_tree *tree, | |
1134 | u64 *start, u64 search_end, u64 max_bytes, | |
1135 | unsigned long bits) | |
1136 | { | |
1137 | struct rb_node *node; | |
1138 | struct extent_state *state; | |
1139 | u64 cur_start = *start; | |
1140 | u64 total_bytes = 0; | |
1141 | int found = 0; | |
1142 | ||
1143 | if (search_end <= cur_start) { | |
1144 | printk("search_end %Lu start %Lu\n", search_end, cur_start); | |
1145 | WARN_ON(1); | |
1146 | return 0; | |
1147 | } | |
1148 | ||
70dec807 | 1149 | spin_lock_irq(&tree->lock); |
d1310b2e CM |
1150 | if (cur_start == 0 && bits == EXTENT_DIRTY) { |
1151 | total_bytes = tree->dirty_bytes; | |
1152 | goto out; | |
1153 | } | |
1154 | /* | |
1155 | * this search will find all the extents that end after | |
1156 | * our range starts. | |
1157 | */ | |
80ea96b1 | 1158 | node = tree_search(tree, cur_start); |
2b114d1d | 1159 | if (!node) { |
d1310b2e CM |
1160 | goto out; |
1161 | } | |
1162 | ||
1163 | while(1) { | |
1164 | state = rb_entry(node, struct extent_state, rb_node); | |
1165 | if (state->start > search_end) | |
1166 | break; | |
1167 | if (state->end >= cur_start && (state->state & bits)) { | |
1168 | total_bytes += min(search_end, state->end) + 1 - | |
1169 | max(cur_start, state->start); | |
1170 | if (total_bytes >= max_bytes) | |
1171 | break; | |
1172 | if (!found) { | |
1173 | *start = state->start; | |
1174 | found = 1; | |
1175 | } | |
1176 | } | |
1177 | node = rb_next(node); | |
1178 | if (!node) | |
1179 | break; | |
1180 | } | |
1181 | out: | |
70dec807 | 1182 | spin_unlock_irq(&tree->lock); |
d1310b2e CM |
1183 | return total_bytes; |
1184 | } | |
1185 | /* | |
1186 | * helper function to lock both pages and extents in the tree. | |
1187 | * pages must be locked first. | |
1188 | */ | |
1189 | int lock_range(struct extent_io_tree *tree, u64 start, u64 end) | |
1190 | { | |
1191 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1192 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
1193 | struct page *page; | |
1194 | int err; | |
1195 | ||
1196 | while (index <= end_index) { | |
1197 | page = grab_cache_page(tree->mapping, index); | |
1198 | if (!page) { | |
1199 | err = -ENOMEM; | |
1200 | goto failed; | |
1201 | } | |
1202 | if (IS_ERR(page)) { | |
1203 | err = PTR_ERR(page); | |
1204 | goto failed; | |
1205 | } | |
1206 | index++; | |
1207 | } | |
1208 | lock_extent(tree, start, end, GFP_NOFS); | |
1209 | return 0; | |
1210 | ||
1211 | failed: | |
1212 | /* | |
1213 | * we failed above in getting the page at 'index', so we undo here | |
1214 | * up to but not including the page at 'index' | |
1215 | */ | |
1216 | end_index = index; | |
1217 | index = start >> PAGE_CACHE_SHIFT; | |
1218 | while (index < end_index) { | |
1219 | page = find_get_page(tree->mapping, index); | |
1220 | unlock_page(page); | |
1221 | page_cache_release(page); | |
1222 | index++; | |
1223 | } | |
1224 | return err; | |
1225 | } | |
1226 | EXPORT_SYMBOL(lock_range); | |
1227 | ||
1228 | /* | |
1229 | * helper function to unlock both pages and extents in the tree. | |
1230 | */ | |
1231 | int unlock_range(struct extent_io_tree *tree, u64 start, u64 end) | |
1232 | { | |
1233 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1234 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
1235 | struct page *page; | |
1236 | ||
1237 | while (index <= end_index) { | |
1238 | page = find_get_page(tree->mapping, index); | |
1239 | unlock_page(page); | |
1240 | page_cache_release(page); | |
1241 | index++; | |
1242 | } | |
1243 | unlock_extent(tree, start, end, GFP_NOFS); | |
1244 | return 0; | |
1245 | } | |
1246 | EXPORT_SYMBOL(unlock_range); | |
1247 | ||
1248 | int set_state_private(struct extent_io_tree *tree, u64 start, u64 private) | |
1249 | { | |
1250 | struct rb_node *node; | |
1251 | struct extent_state *state; | |
1252 | int ret = 0; | |
1253 | ||
70dec807 | 1254 | spin_lock_irq(&tree->lock); |
d1310b2e CM |
1255 | /* |
1256 | * this search will find all the extents that end after | |
1257 | * our range starts. | |
1258 | */ | |
80ea96b1 | 1259 | node = tree_search(tree, start); |
2b114d1d | 1260 | if (!node) { |
d1310b2e CM |
1261 | ret = -ENOENT; |
1262 | goto out; | |
1263 | } | |
1264 | state = rb_entry(node, struct extent_state, rb_node); | |
1265 | if (state->start != start) { | |
1266 | ret = -ENOENT; | |
1267 | goto out; | |
1268 | } | |
1269 | state->private = private; | |
1270 | out: | |
70dec807 | 1271 | spin_unlock_irq(&tree->lock); |
d1310b2e CM |
1272 | return ret; |
1273 | } | |
1274 | ||
1275 | int get_state_private(struct extent_io_tree *tree, u64 start, u64 *private) | |
1276 | { | |
1277 | struct rb_node *node; | |
1278 | struct extent_state *state; | |
1279 | int ret = 0; | |
1280 | ||
70dec807 | 1281 | spin_lock_irq(&tree->lock); |
d1310b2e CM |
1282 | /* |
1283 | * this search will find all the extents that end after | |
1284 | * our range starts. | |
1285 | */ | |
80ea96b1 | 1286 | node = tree_search(tree, start); |
2b114d1d | 1287 | if (!node) { |
d1310b2e CM |
1288 | ret = -ENOENT; |
1289 | goto out; | |
1290 | } | |
1291 | state = rb_entry(node, struct extent_state, rb_node); | |
1292 | if (state->start != start) { | |
1293 | ret = -ENOENT; | |
1294 | goto out; | |
1295 | } | |
1296 | *private = state->private; | |
1297 | out: | |
70dec807 | 1298 | spin_unlock_irq(&tree->lock); |
d1310b2e CM |
1299 | return ret; |
1300 | } | |
1301 | ||
1302 | /* | |
1303 | * searches a range in the state tree for a given mask. | |
70dec807 | 1304 | * If 'filled' == 1, this returns 1 only if every extent in the tree |
d1310b2e CM |
1305 | * has the bits set. Otherwise, 1 is returned if any bit in the |
1306 | * range is found set. | |
1307 | */ | |
1308 | int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end, | |
1309 | int bits, int filled) | |
1310 | { | |
1311 | struct extent_state *state = NULL; | |
1312 | struct rb_node *node; | |
1313 | int bitset = 0; | |
1314 | unsigned long flags; | |
1315 | ||
70dec807 | 1316 | spin_lock_irqsave(&tree->lock, flags); |
80ea96b1 | 1317 | node = tree_search(tree, start); |
d1310b2e CM |
1318 | while (node && start <= end) { |
1319 | state = rb_entry(node, struct extent_state, rb_node); | |
1320 | ||
1321 | if (filled && state->start > start) { | |
1322 | bitset = 0; | |
1323 | break; | |
1324 | } | |
1325 | ||
1326 | if (state->start > end) | |
1327 | break; | |
1328 | ||
1329 | if (state->state & bits) { | |
1330 | bitset = 1; | |
1331 | if (!filled) | |
1332 | break; | |
1333 | } else if (filled) { | |
1334 | bitset = 0; | |
1335 | break; | |
1336 | } | |
1337 | start = state->end + 1; | |
1338 | if (start > end) | |
1339 | break; | |
1340 | node = rb_next(node); | |
1341 | if (!node) { | |
1342 | if (filled) | |
1343 | bitset = 0; | |
1344 | break; | |
1345 | } | |
1346 | } | |
70dec807 | 1347 | spin_unlock_irqrestore(&tree->lock, flags); |
d1310b2e CM |
1348 | return bitset; |
1349 | } | |
1350 | EXPORT_SYMBOL(test_range_bit); | |
1351 | ||
1352 | /* | |
1353 | * helper function to set a given page up to date if all the | |
1354 | * extents in the tree for that page are up to date | |
1355 | */ | |
1356 | static int check_page_uptodate(struct extent_io_tree *tree, | |
1357 | struct page *page) | |
1358 | { | |
1359 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
1360 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
1361 | if (test_range_bit(tree, start, end, EXTENT_UPTODATE, 1)) | |
1362 | SetPageUptodate(page); | |
1363 | return 0; | |
1364 | } | |
1365 | ||
1366 | /* | |
1367 | * helper function to unlock a page if all the extents in the tree | |
1368 | * for that page are unlocked | |
1369 | */ | |
1370 | static int check_page_locked(struct extent_io_tree *tree, | |
1371 | struct page *page) | |
1372 | { | |
1373 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
1374 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
1375 | if (!test_range_bit(tree, start, end, EXTENT_LOCKED, 0)) | |
1376 | unlock_page(page); | |
1377 | return 0; | |
1378 | } | |
1379 | ||
1380 | /* | |
1381 | * helper function to end page writeback if all the extents | |
1382 | * in the tree for that page are done with writeback | |
1383 | */ | |
1384 | static int check_page_writeback(struct extent_io_tree *tree, | |
1385 | struct page *page) | |
1386 | { | |
1387 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
1388 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
1389 | if (!test_range_bit(tree, start, end, EXTENT_WRITEBACK, 0)) | |
1390 | end_page_writeback(page); | |
1391 | return 0; | |
1392 | } | |
1393 | ||
1394 | /* lots and lots of room for performance fixes in the end_bio funcs */ | |
1395 | ||
1396 | /* | |
1397 | * after a writepage IO is done, we need to: | |
1398 | * clear the uptodate bits on error | |
1399 | * clear the writeback bits in the extent tree for this IO | |
1400 | * end_page_writeback if the page has no more pending IO | |
1401 | * | |
1402 | * Scheduling is not allowed, so the extent state tree is expected | |
1403 | * to have one and only one object corresponding to this IO. | |
1404 | */ | |
d1310b2e | 1405 | static void end_bio_extent_writepage(struct bio *bio, int err) |
d1310b2e | 1406 | { |
1259ab75 | 1407 | int uptodate = err == 0; |
d1310b2e | 1408 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; |
902b22f3 | 1409 | struct extent_io_tree *tree; |
d1310b2e CM |
1410 | u64 start; |
1411 | u64 end; | |
1412 | int whole_page; | |
1259ab75 | 1413 | int ret; |
d1310b2e | 1414 | |
d1310b2e CM |
1415 | do { |
1416 | struct page *page = bvec->bv_page; | |
902b22f3 DW |
1417 | tree = &BTRFS_I(page->mapping->host)->io_tree; |
1418 | ||
d1310b2e CM |
1419 | start = ((u64)page->index << PAGE_CACHE_SHIFT) + |
1420 | bvec->bv_offset; | |
1421 | end = start + bvec->bv_len - 1; | |
1422 | ||
1423 | if (bvec->bv_offset == 0 && bvec->bv_len == PAGE_CACHE_SIZE) | |
1424 | whole_page = 1; | |
1425 | else | |
1426 | whole_page = 0; | |
1427 | ||
1428 | if (--bvec >= bio->bi_io_vec) | |
1429 | prefetchw(&bvec->bv_page->flags); | |
1259ab75 CM |
1430 | if (tree->ops && tree->ops->writepage_end_io_hook) { |
1431 | ret = tree->ops->writepage_end_io_hook(page, start, | |
902b22f3 | 1432 | end, NULL, uptodate); |
1259ab75 CM |
1433 | if (ret) |
1434 | uptodate = 0; | |
1435 | } | |
1436 | ||
1437 | if (!uptodate && tree->ops && | |
1438 | tree->ops->writepage_io_failed_hook) { | |
1439 | ret = tree->ops->writepage_io_failed_hook(bio, page, | |
902b22f3 | 1440 | start, end, NULL); |
1259ab75 | 1441 | if (ret == 0) { |
1259ab75 CM |
1442 | uptodate = (err == 0); |
1443 | continue; | |
1444 | } | |
1445 | } | |
1446 | ||
d1310b2e CM |
1447 | if (!uptodate) { |
1448 | clear_extent_uptodate(tree, start, end, GFP_ATOMIC); | |
1449 | ClearPageUptodate(page); | |
1450 | SetPageError(page); | |
1451 | } | |
70dec807 | 1452 | |
902b22f3 | 1453 | clear_extent_writeback(tree, start, end, GFP_ATOMIC); |
d1310b2e CM |
1454 | |
1455 | if (whole_page) | |
1456 | end_page_writeback(page); | |
1457 | else | |
1458 | check_page_writeback(tree, page); | |
d1310b2e | 1459 | } while (bvec >= bio->bi_io_vec); |
2b1f55b0 | 1460 | |
d1310b2e | 1461 | bio_put(bio); |
d1310b2e CM |
1462 | } |
1463 | ||
1464 | /* | |
1465 | * after a readpage IO is done, we need to: | |
1466 | * clear the uptodate bits on error | |
1467 | * set the uptodate bits if things worked | |
1468 | * set the page up to date if all extents in the tree are uptodate | |
1469 | * clear the lock bit in the extent tree | |
1470 | * unlock the page if there are no other extents locked for it | |
1471 | * | |
1472 | * Scheduling is not allowed, so the extent state tree is expected | |
1473 | * to have one and only one object corresponding to this IO. | |
1474 | */ | |
d1310b2e | 1475 | static void end_bio_extent_readpage(struct bio *bio, int err) |
d1310b2e CM |
1476 | { |
1477 | int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); | |
1478 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; | |
902b22f3 | 1479 | struct extent_io_tree *tree; |
d1310b2e CM |
1480 | u64 start; |
1481 | u64 end; | |
1482 | int whole_page; | |
1483 | int ret; | |
1484 | ||
d1310b2e CM |
1485 | do { |
1486 | struct page *page = bvec->bv_page; | |
902b22f3 DW |
1487 | tree = &BTRFS_I(page->mapping->host)->io_tree; |
1488 | ||
d1310b2e CM |
1489 | start = ((u64)page->index << PAGE_CACHE_SHIFT) + |
1490 | bvec->bv_offset; | |
1491 | end = start + bvec->bv_len - 1; | |
1492 | ||
1493 | if (bvec->bv_offset == 0 && bvec->bv_len == PAGE_CACHE_SIZE) | |
1494 | whole_page = 1; | |
1495 | else | |
1496 | whole_page = 0; | |
1497 | ||
1498 | if (--bvec >= bio->bi_io_vec) | |
1499 | prefetchw(&bvec->bv_page->flags); | |
1500 | ||
1501 | if (uptodate && tree->ops && tree->ops->readpage_end_io_hook) { | |
70dec807 | 1502 | ret = tree->ops->readpage_end_io_hook(page, start, end, |
902b22f3 | 1503 | NULL); |
d1310b2e CM |
1504 | if (ret) |
1505 | uptodate = 0; | |
1506 | } | |
7e38326f CM |
1507 | if (!uptodate && tree->ops && |
1508 | tree->ops->readpage_io_failed_hook) { | |
1509 | ret = tree->ops->readpage_io_failed_hook(bio, page, | |
902b22f3 | 1510 | start, end, NULL); |
7e38326f | 1511 | if (ret == 0) { |
3b951516 CM |
1512 | uptodate = |
1513 | test_bit(BIO_UPTODATE, &bio->bi_flags); | |
7e38326f CM |
1514 | continue; |
1515 | } | |
1516 | } | |
d1310b2e | 1517 | |
902b22f3 DW |
1518 | if (uptodate) |
1519 | set_extent_uptodate(tree, start, end, | |
1520 | GFP_ATOMIC); | |
1521 | unlock_extent(tree, start, end, GFP_ATOMIC); | |
d1310b2e | 1522 | |
70dec807 CM |
1523 | if (whole_page) { |
1524 | if (uptodate) { | |
1525 | SetPageUptodate(page); | |
1526 | } else { | |
1527 | ClearPageUptodate(page); | |
1528 | SetPageError(page); | |
1529 | } | |
d1310b2e | 1530 | unlock_page(page); |
70dec807 CM |
1531 | } else { |
1532 | if (uptodate) { | |
1533 | check_page_uptodate(tree, page); | |
1534 | } else { | |
1535 | ClearPageUptodate(page); | |
1536 | SetPageError(page); | |
1537 | } | |
d1310b2e | 1538 | check_page_locked(tree, page); |
70dec807 | 1539 | } |
d1310b2e CM |
1540 | } while (bvec >= bio->bi_io_vec); |
1541 | ||
1542 | bio_put(bio); | |
d1310b2e CM |
1543 | } |
1544 | ||
1545 | /* | |
1546 | * IO done from prepare_write is pretty simple, we just unlock | |
1547 | * the structs in the extent tree when done, and set the uptodate bits | |
1548 | * as appropriate. | |
1549 | */ | |
d1310b2e | 1550 | static void end_bio_extent_preparewrite(struct bio *bio, int err) |
d1310b2e CM |
1551 | { |
1552 | const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); | |
1553 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; | |
902b22f3 | 1554 | struct extent_io_tree *tree; |
d1310b2e CM |
1555 | u64 start; |
1556 | u64 end; | |
1557 | ||
d1310b2e CM |
1558 | do { |
1559 | struct page *page = bvec->bv_page; | |
902b22f3 DW |
1560 | tree = &BTRFS_I(page->mapping->host)->io_tree; |
1561 | ||
d1310b2e CM |
1562 | start = ((u64)page->index << PAGE_CACHE_SHIFT) + |
1563 | bvec->bv_offset; | |
1564 | end = start + bvec->bv_len - 1; | |
1565 | ||
1566 | if (--bvec >= bio->bi_io_vec) | |
1567 | prefetchw(&bvec->bv_page->flags); | |
1568 | ||
1569 | if (uptodate) { | |
1570 | set_extent_uptodate(tree, start, end, GFP_ATOMIC); | |
1571 | } else { | |
1572 | ClearPageUptodate(page); | |
1573 | SetPageError(page); | |
1574 | } | |
1575 | ||
1576 | unlock_extent(tree, start, end, GFP_ATOMIC); | |
1577 | ||
1578 | } while (bvec >= bio->bi_io_vec); | |
1579 | ||
1580 | bio_put(bio); | |
d1310b2e CM |
1581 | } |
1582 | ||
1583 | static struct bio * | |
1584 | extent_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs, | |
1585 | gfp_t gfp_flags) | |
1586 | { | |
1587 | struct bio *bio; | |
1588 | ||
1589 | bio = bio_alloc(gfp_flags, nr_vecs); | |
1590 | ||
1591 | if (bio == NULL && (current->flags & PF_MEMALLOC)) { | |
1592 | while (!bio && (nr_vecs /= 2)) | |
1593 | bio = bio_alloc(gfp_flags, nr_vecs); | |
1594 | } | |
1595 | ||
1596 | if (bio) { | |
e1c4b745 | 1597 | bio->bi_size = 0; |
d1310b2e CM |
1598 | bio->bi_bdev = bdev; |
1599 | bio->bi_sector = first_sector; | |
1600 | } | |
1601 | return bio; | |
1602 | } | |
1603 | ||
f188591e | 1604 | static int submit_one_bio(int rw, struct bio *bio, int mirror_num) |
d1310b2e | 1605 | { |
d1310b2e | 1606 | int ret = 0; |
70dec807 CM |
1607 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; |
1608 | struct page *page = bvec->bv_page; | |
1609 | struct extent_io_tree *tree = bio->bi_private; | |
1610 | struct rb_node *node; | |
1611 | struct extent_state *state; | |
1612 | u64 start; | |
1613 | u64 end; | |
1614 | ||
1615 | start = ((u64)page->index << PAGE_CACHE_SHIFT) + bvec->bv_offset; | |
1616 | end = start + bvec->bv_len - 1; | |
1617 | ||
1618 | spin_lock_irq(&tree->lock); | |
80ea96b1 | 1619 | node = __etree_search(tree, start, NULL, NULL); |
70dec807 CM |
1620 | BUG_ON(!node); |
1621 | state = rb_entry(node, struct extent_state, rb_node); | |
1622 | while(state->end < end) { | |
1623 | node = rb_next(node); | |
1624 | state = rb_entry(node, struct extent_state, rb_node); | |
1625 | } | |
1626 | BUG_ON(state->end != end); | |
1627 | spin_unlock_irq(&tree->lock); | |
1628 | ||
902b22f3 | 1629 | bio->bi_private = NULL; |
d1310b2e CM |
1630 | |
1631 | bio_get(bio); | |
1632 | ||
065631f6 | 1633 | if (tree->ops && tree->ops->submit_bio_hook) |
f188591e CM |
1634 | tree->ops->submit_bio_hook(page->mapping->host, rw, bio, |
1635 | mirror_num); | |
0b86a832 CM |
1636 | else |
1637 | submit_bio(rw, bio); | |
d1310b2e CM |
1638 | if (bio_flagged(bio, BIO_EOPNOTSUPP)) |
1639 | ret = -EOPNOTSUPP; | |
1640 | bio_put(bio); | |
1641 | return ret; | |
1642 | } | |
1643 | ||
1644 | static int submit_extent_page(int rw, struct extent_io_tree *tree, | |
1645 | struct page *page, sector_t sector, | |
1646 | size_t size, unsigned long offset, | |
1647 | struct block_device *bdev, | |
1648 | struct bio **bio_ret, | |
1649 | unsigned long max_pages, | |
f188591e CM |
1650 | bio_end_io_t end_io_func, |
1651 | int mirror_num) | |
d1310b2e CM |
1652 | { |
1653 | int ret = 0; | |
1654 | struct bio *bio; | |
1655 | int nr; | |
1656 | ||
1657 | if (bio_ret && *bio_ret) { | |
1658 | bio = *bio_ret; | |
1659 | if (bio->bi_sector + (bio->bi_size >> 9) != sector || | |
239b14b3 CM |
1660 | (tree->ops && tree->ops->merge_bio_hook && |
1661 | tree->ops->merge_bio_hook(page, offset, size, bio)) || | |
d1310b2e | 1662 | bio_add_page(bio, page, size, offset) < size) { |
f188591e | 1663 | ret = submit_one_bio(rw, bio, mirror_num); |
d1310b2e CM |
1664 | bio = NULL; |
1665 | } else { | |
1666 | return 0; | |
1667 | } | |
1668 | } | |
961d0232 | 1669 | nr = bio_get_nr_vecs(bdev); |
d1310b2e CM |
1670 | bio = extent_bio_alloc(bdev, sector, nr, GFP_NOFS | __GFP_HIGH); |
1671 | if (!bio) { | |
1672 | printk("failed to allocate bio nr %d\n", nr); | |
1673 | } | |
70dec807 CM |
1674 | |
1675 | ||
d1310b2e CM |
1676 | bio_add_page(bio, page, size, offset); |
1677 | bio->bi_end_io = end_io_func; | |
1678 | bio->bi_private = tree; | |
70dec807 | 1679 | |
d1310b2e CM |
1680 | if (bio_ret) { |
1681 | *bio_ret = bio; | |
1682 | } else { | |
f188591e | 1683 | ret = submit_one_bio(rw, bio, mirror_num); |
d1310b2e CM |
1684 | } |
1685 | ||
1686 | return ret; | |
1687 | } | |
1688 | ||
1689 | void set_page_extent_mapped(struct page *page) | |
1690 | { | |
1691 | if (!PagePrivate(page)) { | |
1692 | SetPagePrivate(page); | |
d1310b2e | 1693 | page_cache_get(page); |
6af118ce | 1694 | set_page_private(page, EXTENT_PAGE_PRIVATE); |
d1310b2e CM |
1695 | } |
1696 | } | |
1697 | ||
1698 | void set_page_extent_head(struct page *page, unsigned long len) | |
1699 | { | |
1700 | set_page_private(page, EXTENT_PAGE_PRIVATE_FIRST_PAGE | len << 2); | |
1701 | } | |
1702 | ||
1703 | /* | |
1704 | * basic readpage implementation. Locked extent state structs are inserted | |
1705 | * into the tree that are removed when the IO is done (by the end_io | |
1706 | * handlers) | |
1707 | */ | |
1708 | static int __extent_read_full_page(struct extent_io_tree *tree, | |
1709 | struct page *page, | |
1710 | get_extent_t *get_extent, | |
f188591e | 1711 | struct bio **bio, int mirror_num) |
d1310b2e CM |
1712 | { |
1713 | struct inode *inode = page->mapping->host; | |
1714 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
1715 | u64 page_end = start + PAGE_CACHE_SIZE - 1; | |
1716 | u64 end; | |
1717 | u64 cur = start; | |
1718 | u64 extent_offset; | |
1719 | u64 last_byte = i_size_read(inode); | |
1720 | u64 block_start; | |
1721 | u64 cur_end; | |
1722 | sector_t sector; | |
1723 | struct extent_map *em; | |
1724 | struct block_device *bdev; | |
1725 | int ret; | |
1726 | int nr = 0; | |
1727 | size_t page_offset = 0; | |
1728 | size_t iosize; | |
1729 | size_t blocksize = inode->i_sb->s_blocksize; | |
1730 | ||
1731 | set_page_extent_mapped(page); | |
1732 | ||
1733 | end = page_end; | |
1734 | lock_extent(tree, start, end, GFP_NOFS); | |
1735 | ||
1736 | while (cur <= end) { | |
1737 | if (cur >= last_byte) { | |
1738 | char *userpage; | |
1739 | iosize = PAGE_CACHE_SIZE - page_offset; | |
1740 | userpage = kmap_atomic(page, KM_USER0); | |
1741 | memset(userpage + page_offset, 0, iosize); | |
1742 | flush_dcache_page(page); | |
1743 | kunmap_atomic(userpage, KM_USER0); | |
1744 | set_extent_uptodate(tree, cur, cur + iosize - 1, | |
1745 | GFP_NOFS); | |
1746 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); | |
1747 | break; | |
1748 | } | |
1749 | em = get_extent(inode, page, page_offset, cur, | |
1750 | end - cur + 1, 0); | |
1751 | if (IS_ERR(em) || !em) { | |
1752 | SetPageError(page); | |
1753 | unlock_extent(tree, cur, end, GFP_NOFS); | |
1754 | break; | |
1755 | } | |
d1310b2e | 1756 | extent_offset = cur - em->start; |
e6dcd2dc CM |
1757 | if (extent_map_end(em) <= cur) { |
1758 | printk("bad mapping em [%Lu %Lu] cur %Lu\n", em->start, extent_map_end(em), cur); | |
1759 | } | |
d1310b2e | 1760 | BUG_ON(extent_map_end(em) <= cur); |
e6dcd2dc CM |
1761 | if (end < cur) { |
1762 | printk("2bad mapping end %Lu cur %Lu\n", end, cur); | |
1763 | } | |
d1310b2e CM |
1764 | BUG_ON(end < cur); |
1765 | ||
1766 | iosize = min(extent_map_end(em) - cur, end - cur + 1); | |
1767 | cur_end = min(extent_map_end(em) - 1, end); | |
1768 | iosize = (iosize + blocksize - 1) & ~((u64)blocksize - 1); | |
1769 | sector = (em->block_start + extent_offset) >> 9; | |
1770 | bdev = em->bdev; | |
1771 | block_start = em->block_start; | |
1772 | free_extent_map(em); | |
1773 | em = NULL; | |
1774 | ||
1775 | /* we've found a hole, just zero and go on */ | |
1776 | if (block_start == EXTENT_MAP_HOLE) { | |
1777 | char *userpage; | |
1778 | userpage = kmap_atomic(page, KM_USER0); | |
1779 | memset(userpage + page_offset, 0, iosize); | |
1780 | flush_dcache_page(page); | |
1781 | kunmap_atomic(userpage, KM_USER0); | |
1782 | ||
1783 | set_extent_uptodate(tree, cur, cur + iosize - 1, | |
1784 | GFP_NOFS); | |
1785 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); | |
1786 | cur = cur + iosize; | |
1787 | page_offset += iosize; | |
1788 | continue; | |
1789 | } | |
1790 | /* the get_extent function already copied into the page */ | |
1791 | if (test_range_bit(tree, cur, cur_end, EXTENT_UPTODATE, 1)) { | |
a1b32a59 | 1792 | check_page_uptodate(tree, page); |
d1310b2e CM |
1793 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); |
1794 | cur = cur + iosize; | |
1795 | page_offset += iosize; | |
1796 | continue; | |
1797 | } | |
70dec807 CM |
1798 | /* we have an inline extent but it didn't get marked up |
1799 | * to date. Error out | |
1800 | */ | |
1801 | if (block_start == EXTENT_MAP_INLINE) { | |
1802 | SetPageError(page); | |
1803 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); | |
1804 | cur = cur + iosize; | |
1805 | page_offset += iosize; | |
1806 | continue; | |
1807 | } | |
d1310b2e CM |
1808 | |
1809 | ret = 0; | |
1810 | if (tree->ops && tree->ops->readpage_io_hook) { | |
1811 | ret = tree->ops->readpage_io_hook(page, cur, | |
1812 | cur + iosize - 1); | |
1813 | } | |
1814 | if (!ret) { | |
89642229 CM |
1815 | unsigned long pnr = (last_byte >> PAGE_CACHE_SHIFT) + 1; |
1816 | pnr -= page->index; | |
d1310b2e CM |
1817 | ret = submit_extent_page(READ, tree, page, |
1818 | sector, iosize, page_offset, | |
89642229 | 1819 | bdev, bio, pnr, |
f188591e | 1820 | end_bio_extent_readpage, mirror_num); |
89642229 | 1821 | nr++; |
d1310b2e CM |
1822 | } |
1823 | if (ret) | |
1824 | SetPageError(page); | |
1825 | cur = cur + iosize; | |
1826 | page_offset += iosize; | |
d1310b2e CM |
1827 | } |
1828 | if (!nr) { | |
1829 | if (!PageError(page)) | |
1830 | SetPageUptodate(page); | |
1831 | unlock_page(page); | |
1832 | } | |
1833 | return 0; | |
1834 | } | |
1835 | ||
1836 | int extent_read_full_page(struct extent_io_tree *tree, struct page *page, | |
1837 | get_extent_t *get_extent) | |
1838 | { | |
1839 | struct bio *bio = NULL; | |
1840 | int ret; | |
1841 | ||
f188591e | 1842 | ret = __extent_read_full_page(tree, page, get_extent, &bio, 0); |
d1310b2e | 1843 | if (bio) |
f188591e | 1844 | submit_one_bio(READ, bio, 0); |
d1310b2e CM |
1845 | return ret; |
1846 | } | |
1847 | EXPORT_SYMBOL(extent_read_full_page); | |
1848 | ||
1849 | /* | |
1850 | * the writepage semantics are similar to regular writepage. extent | |
1851 | * records are inserted to lock ranges in the tree, and as dirty areas | |
1852 | * are found, they are marked writeback. Then the lock bits are removed | |
1853 | * and the end_io handler clears the writeback ranges | |
1854 | */ | |
1855 | static int __extent_writepage(struct page *page, struct writeback_control *wbc, | |
1856 | void *data) | |
1857 | { | |
1858 | struct inode *inode = page->mapping->host; | |
1859 | struct extent_page_data *epd = data; | |
1860 | struct extent_io_tree *tree = epd->tree; | |
1861 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
1862 | u64 delalloc_start; | |
1863 | u64 page_end = start + PAGE_CACHE_SIZE - 1; | |
1864 | u64 end; | |
1865 | u64 cur = start; | |
1866 | u64 extent_offset; | |
1867 | u64 last_byte = i_size_read(inode); | |
1868 | u64 block_start; | |
1869 | u64 iosize; | |
e6dcd2dc | 1870 | u64 unlock_start; |
d1310b2e CM |
1871 | sector_t sector; |
1872 | struct extent_map *em; | |
1873 | struct block_device *bdev; | |
1874 | int ret; | |
1875 | int nr = 0; | |
7f3c74fb | 1876 | size_t pg_offset = 0; |
d1310b2e CM |
1877 | size_t blocksize; |
1878 | loff_t i_size = i_size_read(inode); | |
1879 | unsigned long end_index = i_size >> PAGE_CACHE_SHIFT; | |
1880 | u64 nr_delalloc; | |
1881 | u64 delalloc_end; | |
1882 | ||
1883 | WARN_ON(!PageLocked(page)); | |
7f3c74fb | 1884 | pg_offset = i_size & (PAGE_CACHE_SIZE - 1); |
211c17f5 | 1885 | if (page->index > end_index || |
7f3c74fb | 1886 | (page->index == end_index && !pg_offset)) { |
211c17f5 | 1887 | page->mapping->a_ops->invalidatepage(page, 0); |
d1310b2e CM |
1888 | unlock_page(page); |
1889 | return 0; | |
1890 | } | |
1891 | ||
1892 | if (page->index == end_index) { | |
1893 | char *userpage; | |
1894 | ||
d1310b2e | 1895 | userpage = kmap_atomic(page, KM_USER0); |
7f3c74fb CM |
1896 | memset(userpage + pg_offset, 0, |
1897 | PAGE_CACHE_SIZE - pg_offset); | |
d1310b2e | 1898 | kunmap_atomic(userpage, KM_USER0); |
211c17f5 | 1899 | flush_dcache_page(page); |
d1310b2e | 1900 | } |
7f3c74fb | 1901 | pg_offset = 0; |
d1310b2e CM |
1902 | |
1903 | set_page_extent_mapped(page); | |
1904 | ||
1905 | delalloc_start = start; | |
1906 | delalloc_end = 0; | |
1907 | while(delalloc_end < page_end) { | |
1908 | nr_delalloc = find_lock_delalloc_range(tree, &delalloc_start, | |
1909 | &delalloc_end, | |
1910 | 128 * 1024 * 1024); | |
1911 | if (nr_delalloc == 0) { | |
1912 | delalloc_start = delalloc_end + 1; | |
1913 | continue; | |
1914 | } | |
1915 | tree->ops->fill_delalloc(inode, delalloc_start, | |
1916 | delalloc_end); | |
1917 | clear_extent_bit(tree, delalloc_start, | |
1918 | delalloc_end, | |
1919 | EXTENT_LOCKED | EXTENT_DELALLOC, | |
1920 | 1, 0, GFP_NOFS); | |
1921 | delalloc_start = delalloc_end + 1; | |
1922 | } | |
1923 | lock_extent(tree, start, page_end, GFP_NOFS); | |
e6dcd2dc | 1924 | unlock_start = start; |
d1310b2e | 1925 | |
247e743c CM |
1926 | if (tree->ops && tree->ops->writepage_start_hook) { |
1927 | ret = tree->ops->writepage_start_hook(page, start, page_end); | |
1928 | if (ret == -EAGAIN) { | |
1929 | unlock_extent(tree, start, page_end, GFP_NOFS); | |
1930 | redirty_page_for_writepage(wbc, page); | |
1931 | unlock_page(page); | |
1932 | return 0; | |
1933 | } | |
1934 | } | |
1935 | ||
d1310b2e CM |
1936 | end = page_end; |
1937 | if (test_range_bit(tree, start, page_end, EXTENT_DELALLOC, 0)) { | |
1938 | printk("found delalloc bits after lock_extent\n"); | |
1939 | } | |
1940 | ||
1941 | if (last_byte <= start) { | |
1942 | clear_extent_dirty(tree, start, page_end, GFP_NOFS); | |
e6dcd2dc CM |
1943 | unlock_extent(tree, start, page_end, GFP_NOFS); |
1944 | if (tree->ops && tree->ops->writepage_end_io_hook) | |
1945 | tree->ops->writepage_end_io_hook(page, start, | |
1946 | page_end, NULL, 1); | |
1947 | unlock_start = page_end + 1; | |
d1310b2e CM |
1948 | goto done; |
1949 | } | |
1950 | ||
1951 | set_extent_uptodate(tree, start, page_end, GFP_NOFS); | |
1952 | blocksize = inode->i_sb->s_blocksize; | |
1953 | ||
1954 | while (cur <= end) { | |
1955 | if (cur >= last_byte) { | |
1956 | clear_extent_dirty(tree, cur, page_end, GFP_NOFS); | |
e6dcd2dc CM |
1957 | unlock_extent(tree, unlock_start, page_end, GFP_NOFS); |
1958 | if (tree->ops && tree->ops->writepage_end_io_hook) | |
1959 | tree->ops->writepage_end_io_hook(page, cur, | |
1960 | page_end, NULL, 1); | |
1961 | unlock_start = page_end + 1; | |
d1310b2e CM |
1962 | break; |
1963 | } | |
7f3c74fb | 1964 | em = epd->get_extent(inode, page, pg_offset, cur, |
d1310b2e CM |
1965 | end - cur + 1, 1); |
1966 | if (IS_ERR(em) || !em) { | |
1967 | SetPageError(page); | |
1968 | break; | |
1969 | } | |
1970 | ||
1971 | extent_offset = cur - em->start; | |
1972 | BUG_ON(extent_map_end(em) <= cur); | |
1973 | BUG_ON(end < cur); | |
1974 | iosize = min(extent_map_end(em) - cur, end - cur + 1); | |
1975 | iosize = (iosize + blocksize - 1) & ~((u64)blocksize - 1); | |
1976 | sector = (em->block_start + extent_offset) >> 9; | |
1977 | bdev = em->bdev; | |
1978 | block_start = em->block_start; | |
1979 | free_extent_map(em); | |
1980 | em = NULL; | |
1981 | ||
1982 | if (block_start == EXTENT_MAP_HOLE || | |
1983 | block_start == EXTENT_MAP_INLINE) { | |
1984 | clear_extent_dirty(tree, cur, | |
1985 | cur + iosize - 1, GFP_NOFS); | |
e6dcd2dc CM |
1986 | |
1987 | unlock_extent(tree, unlock_start, cur + iosize -1, | |
1988 | GFP_NOFS); | |
7f3c74fb | 1989 | |
e6dcd2dc CM |
1990 | if (tree->ops && tree->ops->writepage_end_io_hook) |
1991 | tree->ops->writepage_end_io_hook(page, cur, | |
1992 | cur + iosize - 1, | |
1993 | NULL, 1); | |
d1310b2e | 1994 | cur = cur + iosize; |
7f3c74fb | 1995 | pg_offset += iosize; |
e6dcd2dc | 1996 | unlock_start = cur; |
d1310b2e CM |
1997 | continue; |
1998 | } | |
1999 | ||
2000 | /* leave this out until we have a page_mkwrite call */ | |
2001 | if (0 && !test_range_bit(tree, cur, cur + iosize - 1, | |
2002 | EXTENT_DIRTY, 0)) { | |
2003 | cur = cur + iosize; | |
7f3c74fb | 2004 | pg_offset += iosize; |
d1310b2e CM |
2005 | continue; |
2006 | } | |
2007 | clear_extent_dirty(tree, cur, cur + iosize - 1, GFP_NOFS); | |
2008 | if (tree->ops && tree->ops->writepage_io_hook) { | |
2009 | ret = tree->ops->writepage_io_hook(page, cur, | |
2010 | cur + iosize - 1); | |
2011 | } else { | |
2012 | ret = 0; | |
2013 | } | |
1259ab75 | 2014 | if (ret) { |
d1310b2e | 2015 | SetPageError(page); |
1259ab75 | 2016 | } else { |
d1310b2e | 2017 | unsigned long max_nr = end_index + 1; |
7f3c74fb | 2018 | |
d1310b2e CM |
2019 | set_range_writeback(tree, cur, cur + iosize - 1); |
2020 | if (!PageWriteback(page)) { | |
2021 | printk("warning page %lu not writeback, " | |
2022 | "cur %llu end %llu\n", page->index, | |
2023 | (unsigned long long)cur, | |
2024 | (unsigned long long)end); | |
2025 | } | |
2026 | ||
2027 | ret = submit_extent_page(WRITE, tree, page, sector, | |
7f3c74fb | 2028 | iosize, pg_offset, bdev, |
d1310b2e | 2029 | &epd->bio, max_nr, |
f188591e | 2030 | end_bio_extent_writepage, 0); |
d1310b2e CM |
2031 | if (ret) |
2032 | SetPageError(page); | |
2033 | } | |
2034 | cur = cur + iosize; | |
7f3c74fb | 2035 | pg_offset += iosize; |
d1310b2e CM |
2036 | nr++; |
2037 | } | |
2038 | done: | |
2039 | if (nr == 0) { | |
2040 | /* make sure the mapping tag for page dirty gets cleared */ | |
2041 | set_page_writeback(page); | |
2042 | end_page_writeback(page); | |
2043 | } | |
e6dcd2dc CM |
2044 | if (unlock_start <= page_end) |
2045 | unlock_extent(tree, unlock_start, page_end, GFP_NOFS); | |
d1310b2e CM |
2046 | unlock_page(page); |
2047 | return 0; | |
2048 | } | |
2049 | ||
d1310b2e | 2050 | /** |
4bef0848 | 2051 | * write_cache_pages - walk the list of dirty pages of the given address space and write all of them. |
d1310b2e CM |
2052 | * @mapping: address space structure to write |
2053 | * @wbc: subtract the number of written pages from *@wbc->nr_to_write | |
2054 | * @writepage: function called for each page | |
2055 | * @data: data passed to writepage function | |
2056 | * | |
2057 | * If a page is already under I/O, write_cache_pages() skips it, even | |
2058 | * if it's dirty. This is desirable behaviour for memory-cleaning writeback, | |
2059 | * but it is INCORRECT for data-integrity system calls such as fsync(). fsync() | |
2060 | * and msync() need to guarantee that all the data which was dirty at the time | |
2061 | * the call was made get new I/O started against them. If wbc->sync_mode is | |
2062 | * WB_SYNC_ALL then we were called for data integrity and we must wait for | |
2063 | * existing IO to complete. | |
2064 | */ | |
4bef0848 CM |
2065 | int extent_write_cache_pages(struct extent_io_tree *tree, |
2066 | struct address_space *mapping, | |
2067 | struct writeback_control *wbc, | |
2068 | writepage_t writepage, void *data) | |
d1310b2e CM |
2069 | { |
2070 | struct backing_dev_info *bdi = mapping->backing_dev_info; | |
2071 | int ret = 0; | |
2072 | int done = 0; | |
2073 | struct pagevec pvec; | |
2074 | int nr_pages; | |
2075 | pgoff_t index; | |
2076 | pgoff_t end; /* Inclusive */ | |
2077 | int scanned = 0; | |
2078 | int range_whole = 0; | |
2079 | ||
2080 | if (wbc->nonblocking && bdi_write_congested(bdi)) { | |
2081 | wbc->encountered_congestion = 1; | |
2082 | return 0; | |
2083 | } | |
2084 | ||
2085 | pagevec_init(&pvec, 0); | |
2086 | if (wbc->range_cyclic) { | |
2087 | index = mapping->writeback_index; /* Start from prev offset */ | |
2088 | end = -1; | |
2089 | } else { | |
2090 | index = wbc->range_start >> PAGE_CACHE_SHIFT; | |
2091 | end = wbc->range_end >> PAGE_CACHE_SHIFT; | |
2092 | if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) | |
2093 | range_whole = 1; | |
2094 | scanned = 1; | |
2095 | } | |
2096 | retry: | |
2097 | while (!done && (index <= end) && | |
2098 | (nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, | |
2099 | PAGECACHE_TAG_DIRTY, | |
2100 | min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1))) { | |
2101 | unsigned i; | |
2102 | ||
2103 | scanned = 1; | |
2104 | for (i = 0; i < nr_pages; i++) { | |
2105 | struct page *page = pvec.pages[i]; | |
2106 | ||
2107 | /* | |
2108 | * At this point we hold neither mapping->tree_lock nor | |
2109 | * lock on the page itself: the page may be truncated or | |
2110 | * invalidated (changing page->mapping to NULL), or even | |
2111 | * swizzled back from swapper_space to tmpfs file | |
2112 | * mapping | |
2113 | */ | |
4bef0848 CM |
2114 | if (tree->ops && tree->ops->write_cache_pages_lock_hook) |
2115 | tree->ops->write_cache_pages_lock_hook(page); | |
2116 | else | |
2117 | lock_page(page); | |
d1310b2e CM |
2118 | |
2119 | if (unlikely(page->mapping != mapping)) { | |
2120 | unlock_page(page); | |
2121 | continue; | |
2122 | } | |
2123 | ||
2124 | if (!wbc->range_cyclic && page->index > end) { | |
2125 | done = 1; | |
2126 | unlock_page(page); | |
2127 | continue; | |
2128 | } | |
2129 | ||
2130 | if (wbc->sync_mode != WB_SYNC_NONE) | |
2131 | wait_on_page_writeback(page); | |
2132 | ||
2133 | if (PageWriteback(page) || | |
2134 | !clear_page_dirty_for_io(page)) { | |
2135 | unlock_page(page); | |
2136 | continue; | |
2137 | } | |
2138 | ||
2139 | ret = (*writepage)(page, wbc, data); | |
2140 | ||
2141 | if (unlikely(ret == AOP_WRITEPAGE_ACTIVATE)) { | |
2142 | unlock_page(page); | |
2143 | ret = 0; | |
2144 | } | |
2145 | if (ret || (--(wbc->nr_to_write) <= 0)) | |
2146 | done = 1; | |
2147 | if (wbc->nonblocking && bdi_write_congested(bdi)) { | |
2148 | wbc->encountered_congestion = 1; | |
2149 | done = 1; | |
2150 | } | |
2151 | } | |
2152 | pagevec_release(&pvec); | |
2153 | cond_resched(); | |
2154 | } | |
2155 | if (!scanned && !done) { | |
2156 | /* | |
2157 | * We hit the last page and there is more work to be done: wrap | |
2158 | * back to the start of the file | |
2159 | */ | |
2160 | scanned = 1; | |
2161 | index = 0; | |
2162 | goto retry; | |
2163 | } | |
2164 | if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0)) | |
2165 | mapping->writeback_index = index; | |
2b1f55b0 | 2166 | |
4bef0848 CM |
2167 | if (wbc->range_cont) |
2168 | wbc->range_start = index << PAGE_CACHE_SHIFT; | |
d1310b2e CM |
2169 | return ret; |
2170 | } | |
4bef0848 | 2171 | EXPORT_SYMBOL(extent_write_cache_pages); |
d1310b2e CM |
2172 | |
2173 | int extent_write_full_page(struct extent_io_tree *tree, struct page *page, | |
2174 | get_extent_t *get_extent, | |
2175 | struct writeback_control *wbc) | |
2176 | { | |
2177 | int ret; | |
2178 | struct address_space *mapping = page->mapping; | |
2179 | struct extent_page_data epd = { | |
2180 | .bio = NULL, | |
2181 | .tree = tree, | |
2182 | .get_extent = get_extent, | |
2183 | }; | |
2184 | struct writeback_control wbc_writepages = { | |
2185 | .bdi = wbc->bdi, | |
2186 | .sync_mode = WB_SYNC_NONE, | |
2187 | .older_than_this = NULL, | |
2188 | .nr_to_write = 64, | |
2189 | .range_start = page_offset(page) + PAGE_CACHE_SIZE, | |
2190 | .range_end = (loff_t)-1, | |
2191 | }; | |
2192 | ||
2193 | ||
2194 | ret = __extent_writepage(page, wbc, &epd); | |
2195 | ||
4bef0848 CM |
2196 | extent_write_cache_pages(tree, mapping, &wbc_writepages, |
2197 | __extent_writepage, &epd); | |
d1310b2e | 2198 | if (epd.bio) { |
f188591e | 2199 | submit_one_bio(WRITE, epd.bio, 0); |
d1310b2e CM |
2200 | } |
2201 | return ret; | |
2202 | } | |
2203 | EXPORT_SYMBOL(extent_write_full_page); | |
2204 | ||
2205 | ||
2206 | int extent_writepages(struct extent_io_tree *tree, | |
2207 | struct address_space *mapping, | |
2208 | get_extent_t *get_extent, | |
2209 | struct writeback_control *wbc) | |
2210 | { | |
2211 | int ret = 0; | |
2212 | struct extent_page_data epd = { | |
2213 | .bio = NULL, | |
2214 | .tree = tree, | |
2215 | .get_extent = get_extent, | |
2216 | }; | |
2217 | ||
4bef0848 CM |
2218 | ret = extent_write_cache_pages(tree, mapping, wbc, |
2219 | __extent_writepage, &epd); | |
d1310b2e | 2220 | if (epd.bio) { |
f188591e | 2221 | submit_one_bio(WRITE, epd.bio, 0); |
d1310b2e CM |
2222 | } |
2223 | return ret; | |
2224 | } | |
2225 | EXPORT_SYMBOL(extent_writepages); | |
2226 | ||
2227 | int extent_readpages(struct extent_io_tree *tree, | |
2228 | struct address_space *mapping, | |
2229 | struct list_head *pages, unsigned nr_pages, | |
2230 | get_extent_t get_extent) | |
2231 | { | |
2232 | struct bio *bio = NULL; | |
2233 | unsigned page_idx; | |
2234 | struct pagevec pvec; | |
2235 | ||
2236 | pagevec_init(&pvec, 0); | |
2237 | for (page_idx = 0; page_idx < nr_pages; page_idx++) { | |
2238 | struct page *page = list_entry(pages->prev, struct page, lru); | |
2239 | ||
2240 | prefetchw(&page->flags); | |
2241 | list_del(&page->lru); | |
2242 | /* | |
2243 | * what we want to do here is call add_to_page_cache_lru, | |
2244 | * but that isn't exported, so we reproduce it here | |
2245 | */ | |
2246 | if (!add_to_page_cache(page, mapping, | |
2247 | page->index, GFP_KERNEL)) { | |
2248 | ||
2249 | /* open coding of lru_cache_add, also not exported */ | |
2250 | page_cache_get(page); | |
2251 | if (!pagevec_add(&pvec, page)) | |
2252 | __pagevec_lru_add(&pvec); | |
f188591e CM |
2253 | __extent_read_full_page(tree, page, get_extent, |
2254 | &bio, 0); | |
d1310b2e CM |
2255 | } |
2256 | page_cache_release(page); | |
2257 | } | |
2258 | if (pagevec_count(&pvec)) | |
2259 | __pagevec_lru_add(&pvec); | |
2260 | BUG_ON(!list_empty(pages)); | |
2261 | if (bio) | |
f188591e | 2262 | submit_one_bio(READ, bio, 0); |
d1310b2e CM |
2263 | return 0; |
2264 | } | |
2265 | EXPORT_SYMBOL(extent_readpages); | |
2266 | ||
2267 | /* | |
2268 | * basic invalidatepage code, this waits on any locked or writeback | |
2269 | * ranges corresponding to the page, and then deletes any extent state | |
2270 | * records from the tree | |
2271 | */ | |
2272 | int extent_invalidatepage(struct extent_io_tree *tree, | |
2273 | struct page *page, unsigned long offset) | |
2274 | { | |
2275 | u64 start = ((u64)page->index << PAGE_CACHE_SHIFT); | |
2276 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
2277 | size_t blocksize = page->mapping->host->i_sb->s_blocksize; | |
2278 | ||
2279 | start += (offset + blocksize -1) & ~(blocksize - 1); | |
2280 | if (start > end) | |
2281 | return 0; | |
2282 | ||
2283 | lock_extent(tree, start, end, GFP_NOFS); | |
2284 | wait_on_extent_writeback(tree, start, end); | |
2285 | clear_extent_bit(tree, start, end, | |
2286 | EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC, | |
2287 | 1, 1, GFP_NOFS); | |
2288 | return 0; | |
2289 | } | |
2290 | EXPORT_SYMBOL(extent_invalidatepage); | |
2291 | ||
2292 | /* | |
2293 | * simple commit_write call, set_range_dirty is used to mark both | |
2294 | * the pages and the extent records as dirty | |
2295 | */ | |
2296 | int extent_commit_write(struct extent_io_tree *tree, | |
2297 | struct inode *inode, struct page *page, | |
2298 | unsigned from, unsigned to) | |
2299 | { | |
2300 | loff_t pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to; | |
2301 | ||
2302 | set_page_extent_mapped(page); | |
2303 | set_page_dirty(page); | |
2304 | ||
2305 | if (pos > inode->i_size) { | |
2306 | i_size_write(inode, pos); | |
2307 | mark_inode_dirty(inode); | |
2308 | } | |
2309 | return 0; | |
2310 | } | |
2311 | EXPORT_SYMBOL(extent_commit_write); | |
2312 | ||
2313 | int extent_prepare_write(struct extent_io_tree *tree, | |
2314 | struct inode *inode, struct page *page, | |
2315 | unsigned from, unsigned to, get_extent_t *get_extent) | |
2316 | { | |
2317 | u64 page_start = (u64)page->index << PAGE_CACHE_SHIFT; | |
2318 | u64 page_end = page_start + PAGE_CACHE_SIZE - 1; | |
2319 | u64 block_start; | |
2320 | u64 orig_block_start; | |
2321 | u64 block_end; | |
2322 | u64 cur_end; | |
2323 | struct extent_map *em; | |
2324 | unsigned blocksize = 1 << inode->i_blkbits; | |
2325 | size_t page_offset = 0; | |
2326 | size_t block_off_start; | |
2327 | size_t block_off_end; | |
2328 | int err = 0; | |
2329 | int iocount = 0; | |
2330 | int ret = 0; | |
2331 | int isnew; | |
2332 | ||
2333 | set_page_extent_mapped(page); | |
2334 | ||
2335 | block_start = (page_start + from) & ~((u64)blocksize - 1); | |
2336 | block_end = (page_start + to - 1) | (blocksize - 1); | |
2337 | orig_block_start = block_start; | |
2338 | ||
2339 | lock_extent(tree, page_start, page_end, GFP_NOFS); | |
2340 | while(block_start <= block_end) { | |
2341 | em = get_extent(inode, page, page_offset, block_start, | |
2342 | block_end - block_start + 1, 1); | |
2343 | if (IS_ERR(em) || !em) { | |
2344 | goto err; | |
2345 | } | |
2346 | cur_end = min(block_end, extent_map_end(em) - 1); | |
2347 | block_off_start = block_start & (PAGE_CACHE_SIZE - 1); | |
2348 | block_off_end = block_off_start + blocksize; | |
2349 | isnew = clear_extent_new(tree, block_start, cur_end, GFP_NOFS); | |
2350 | ||
2351 | if (!PageUptodate(page) && isnew && | |
2352 | (block_off_end > to || block_off_start < from)) { | |
2353 | void *kaddr; | |
2354 | ||
2355 | kaddr = kmap_atomic(page, KM_USER0); | |
2356 | if (block_off_end > to) | |
2357 | memset(kaddr + to, 0, block_off_end - to); | |
2358 | if (block_off_start < from) | |
2359 | memset(kaddr + block_off_start, 0, | |
2360 | from - block_off_start); | |
2361 | flush_dcache_page(page); | |
2362 | kunmap_atomic(kaddr, KM_USER0); | |
2363 | } | |
2364 | if ((em->block_start != EXTENT_MAP_HOLE && | |
2365 | em->block_start != EXTENT_MAP_INLINE) && | |
2366 | !isnew && !PageUptodate(page) && | |
2367 | (block_off_end > to || block_off_start < from) && | |
2368 | !test_range_bit(tree, block_start, cur_end, | |
2369 | EXTENT_UPTODATE, 1)) { | |
2370 | u64 sector; | |
2371 | u64 extent_offset = block_start - em->start; | |
2372 | size_t iosize; | |
2373 | sector = (em->block_start + extent_offset) >> 9; | |
2374 | iosize = (cur_end - block_start + blocksize) & | |
2375 | ~((u64)blocksize - 1); | |
2376 | /* | |
2377 | * we've already got the extent locked, but we | |
2378 | * need to split the state such that our end_bio | |
2379 | * handler can clear the lock. | |
2380 | */ | |
2381 | set_extent_bit(tree, block_start, | |
2382 | block_start + iosize - 1, | |
2383 | EXTENT_LOCKED, 0, NULL, GFP_NOFS); | |
2384 | ret = submit_extent_page(READ, tree, page, | |
2385 | sector, iosize, page_offset, em->bdev, | |
2386 | NULL, 1, | |
f188591e | 2387 | end_bio_extent_preparewrite, 0); |
d1310b2e CM |
2388 | iocount++; |
2389 | block_start = block_start + iosize; | |
2390 | } else { | |
2391 | set_extent_uptodate(tree, block_start, cur_end, | |
2392 | GFP_NOFS); | |
2393 | unlock_extent(tree, block_start, cur_end, GFP_NOFS); | |
2394 | block_start = cur_end + 1; | |
2395 | } | |
2396 | page_offset = block_start & (PAGE_CACHE_SIZE - 1); | |
2397 | free_extent_map(em); | |
2398 | } | |
2399 | if (iocount) { | |
2400 | wait_extent_bit(tree, orig_block_start, | |
2401 | block_end, EXTENT_LOCKED); | |
2402 | } | |
2403 | check_page_uptodate(tree, page); | |
2404 | err: | |
2405 | /* FIXME, zero out newly allocated blocks on error */ | |
2406 | return err; | |
2407 | } | |
2408 | EXPORT_SYMBOL(extent_prepare_write); | |
2409 | ||
7b13b7b1 CM |
2410 | /* |
2411 | * a helper for releasepage, this tests for areas of the page that | |
2412 | * are locked or under IO and drops the related state bits if it is safe | |
2413 | * to drop the page. | |
2414 | */ | |
2415 | int try_release_extent_state(struct extent_map_tree *map, | |
2416 | struct extent_io_tree *tree, struct page *page, | |
2417 | gfp_t mask) | |
2418 | { | |
2419 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
2420 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
2421 | int ret = 1; | |
2422 | ||
211f90e6 CM |
2423 | if (test_range_bit(tree, start, end, |
2424 | EXTENT_IOBITS | EXTENT_ORDERED, 0)) | |
7b13b7b1 CM |
2425 | ret = 0; |
2426 | else { | |
2427 | if ((mask & GFP_NOFS) == GFP_NOFS) | |
2428 | mask = GFP_NOFS; | |
2429 | clear_extent_bit(tree, start, end, EXTENT_UPTODATE, | |
2430 | 1, 1, mask); | |
2431 | } | |
2432 | return ret; | |
2433 | } | |
2434 | EXPORT_SYMBOL(try_release_extent_state); | |
2435 | ||
d1310b2e CM |
2436 | /* |
2437 | * a helper for releasepage. As long as there are no locked extents | |
2438 | * in the range corresponding to the page, both state records and extent | |
2439 | * map records are removed | |
2440 | */ | |
2441 | int try_release_extent_mapping(struct extent_map_tree *map, | |
70dec807 CM |
2442 | struct extent_io_tree *tree, struct page *page, |
2443 | gfp_t mask) | |
d1310b2e CM |
2444 | { |
2445 | struct extent_map *em; | |
2446 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
2447 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
7b13b7b1 | 2448 | |
70dec807 CM |
2449 | if ((mask & __GFP_WAIT) && |
2450 | page->mapping->host->i_size > 16 * 1024 * 1024) { | |
39b5637f | 2451 | u64 len; |
70dec807 | 2452 | while (start <= end) { |
39b5637f | 2453 | len = end - start + 1; |
70dec807 | 2454 | spin_lock(&map->lock); |
39b5637f | 2455 | em = lookup_extent_mapping(map, start, len); |
70dec807 CM |
2456 | if (!em || IS_ERR(em)) { |
2457 | spin_unlock(&map->lock); | |
2458 | break; | |
2459 | } | |
7f3c74fb CM |
2460 | if (test_bit(EXTENT_FLAG_PINNED, &em->flags) || |
2461 | em->start != start) { | |
70dec807 CM |
2462 | spin_unlock(&map->lock); |
2463 | free_extent_map(em); | |
2464 | break; | |
2465 | } | |
2466 | if (!test_range_bit(tree, em->start, | |
2467 | extent_map_end(em) - 1, | |
2468 | EXTENT_LOCKED, 0)) { | |
2469 | remove_extent_mapping(map, em); | |
2470 | /* once for the rb tree */ | |
2471 | free_extent_map(em); | |
2472 | } | |
2473 | start = extent_map_end(em); | |
d1310b2e | 2474 | spin_unlock(&map->lock); |
70dec807 CM |
2475 | |
2476 | /* once for us */ | |
d1310b2e CM |
2477 | free_extent_map(em); |
2478 | } | |
d1310b2e | 2479 | } |
7b13b7b1 | 2480 | return try_release_extent_state(map, tree, page, mask); |
d1310b2e CM |
2481 | } |
2482 | EXPORT_SYMBOL(try_release_extent_mapping); | |
2483 | ||
2484 | sector_t extent_bmap(struct address_space *mapping, sector_t iblock, | |
2485 | get_extent_t *get_extent) | |
2486 | { | |
2487 | struct inode *inode = mapping->host; | |
2488 | u64 start = iblock << inode->i_blkbits; | |
2489 | sector_t sector = 0; | |
2490 | struct extent_map *em; | |
2491 | ||
2492 | em = get_extent(inode, NULL, 0, start, (1 << inode->i_blkbits), 0); | |
2493 | if (!em || IS_ERR(em)) | |
2494 | return 0; | |
2495 | ||
2496 | if (em->block_start == EXTENT_MAP_INLINE || | |
2497 | em->block_start == EXTENT_MAP_HOLE) | |
2498 | goto out; | |
2499 | ||
2500 | sector = (em->block_start + start - em->start) >> inode->i_blkbits; | |
d1310b2e CM |
2501 | out: |
2502 | free_extent_map(em); | |
2503 | return sector; | |
2504 | } | |
2505 | ||
d1310b2e CM |
2506 | static inline struct page *extent_buffer_page(struct extent_buffer *eb, |
2507 | unsigned long i) | |
2508 | { | |
2509 | struct page *p; | |
2510 | struct address_space *mapping; | |
2511 | ||
2512 | if (i == 0) | |
2513 | return eb->first_page; | |
2514 | i += eb->start >> PAGE_CACHE_SHIFT; | |
2515 | mapping = eb->first_page->mapping; | |
33958dc6 CM |
2516 | if (!mapping) |
2517 | return NULL; | |
0ee0fda0 SW |
2518 | |
2519 | /* | |
2520 | * extent_buffer_page is only called after pinning the page | |
2521 | * by increasing the reference count. So we know the page must | |
2522 | * be in the radix tree. | |
2523 | */ | |
0ee0fda0 | 2524 | rcu_read_lock(); |
d1310b2e | 2525 | p = radix_tree_lookup(&mapping->page_tree, i); |
0ee0fda0 | 2526 | rcu_read_unlock(); |
2b1f55b0 | 2527 | |
d1310b2e CM |
2528 | return p; |
2529 | } | |
2530 | ||
6af118ce | 2531 | static inline unsigned long num_extent_pages(u64 start, u64 len) |
728131d8 | 2532 | { |
6af118ce CM |
2533 | return ((start + len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT) - |
2534 | (start >> PAGE_CACHE_SHIFT); | |
728131d8 CM |
2535 | } |
2536 | ||
d1310b2e CM |
2537 | static struct extent_buffer *__alloc_extent_buffer(struct extent_io_tree *tree, |
2538 | u64 start, | |
2539 | unsigned long len, | |
2540 | gfp_t mask) | |
2541 | { | |
2542 | struct extent_buffer *eb = NULL; | |
4bef0848 | 2543 | #ifdef LEAK_DEBUG |
2d2ae547 | 2544 | unsigned long flags; |
4bef0848 | 2545 | #endif |
d1310b2e | 2546 | |
d1310b2e | 2547 | eb = kmem_cache_zalloc(extent_buffer_cache, mask); |
d1310b2e CM |
2548 | eb->start = start; |
2549 | eb->len = len; | |
a61e6f29 | 2550 | mutex_init(&eb->mutex); |
4bef0848 | 2551 | #ifdef LEAK_DEBUG |
2d2ae547 CM |
2552 | spin_lock_irqsave(&leak_lock, flags); |
2553 | list_add(&eb->leak_list, &buffers); | |
2554 | spin_unlock_irqrestore(&leak_lock, flags); | |
4bef0848 | 2555 | #endif |
d1310b2e CM |
2556 | atomic_set(&eb->refs, 1); |
2557 | ||
2558 | return eb; | |
2559 | } | |
2560 | ||
2561 | static void __free_extent_buffer(struct extent_buffer *eb) | |
2562 | { | |
4bef0848 | 2563 | #ifdef LEAK_DEBUG |
2d2ae547 CM |
2564 | unsigned long flags; |
2565 | spin_lock_irqsave(&leak_lock, flags); | |
2566 | list_del(&eb->leak_list); | |
2567 | spin_unlock_irqrestore(&leak_lock, flags); | |
4bef0848 | 2568 | #endif |
d1310b2e CM |
2569 | kmem_cache_free(extent_buffer_cache, eb); |
2570 | } | |
2571 | ||
2572 | struct extent_buffer *alloc_extent_buffer(struct extent_io_tree *tree, | |
2573 | u64 start, unsigned long len, | |
2574 | struct page *page0, | |
2575 | gfp_t mask) | |
2576 | { | |
2577 | unsigned long num_pages = num_extent_pages(start, len); | |
2578 | unsigned long i; | |
2579 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
2580 | struct extent_buffer *eb; | |
6af118ce | 2581 | struct extent_buffer *exists = NULL; |
d1310b2e CM |
2582 | struct page *p; |
2583 | struct address_space *mapping = tree->mapping; | |
2584 | int uptodate = 1; | |
2585 | ||
6af118ce CM |
2586 | spin_lock(&tree->buffer_lock); |
2587 | eb = buffer_search(tree, start); | |
2588 | if (eb) { | |
2589 | atomic_inc(&eb->refs); | |
2590 | spin_unlock(&tree->buffer_lock); | |
0f9dd46c | 2591 | mark_page_accessed(eb->first_page); |
6af118ce CM |
2592 | return eb; |
2593 | } | |
2594 | spin_unlock(&tree->buffer_lock); | |
2595 | ||
d1310b2e | 2596 | eb = __alloc_extent_buffer(tree, start, len, mask); |
2b114d1d | 2597 | if (!eb) |
d1310b2e CM |
2598 | return NULL; |
2599 | ||
d1310b2e CM |
2600 | if (page0) { |
2601 | eb->first_page = page0; | |
2602 | i = 1; | |
2603 | index++; | |
2604 | page_cache_get(page0); | |
2605 | mark_page_accessed(page0); | |
2606 | set_page_extent_mapped(page0); | |
d1310b2e | 2607 | set_page_extent_head(page0, len); |
f188591e | 2608 | uptodate = PageUptodate(page0); |
d1310b2e CM |
2609 | } else { |
2610 | i = 0; | |
2611 | } | |
2612 | for (; i < num_pages; i++, index++) { | |
2613 | p = find_or_create_page(mapping, index, mask | __GFP_HIGHMEM); | |
2614 | if (!p) { | |
2615 | WARN_ON(1); | |
6af118ce | 2616 | goto free_eb; |
d1310b2e CM |
2617 | } |
2618 | set_page_extent_mapped(p); | |
2619 | mark_page_accessed(p); | |
2620 | if (i == 0) { | |
2621 | eb->first_page = p; | |
2622 | set_page_extent_head(p, len); | |
2623 | } else { | |
2624 | set_page_private(p, EXTENT_PAGE_PRIVATE); | |
2625 | } | |
2626 | if (!PageUptodate(p)) | |
2627 | uptodate = 0; | |
2628 | unlock_page(p); | |
2629 | } | |
2630 | if (uptodate) | |
2631 | eb->flags |= EXTENT_UPTODATE; | |
2632 | eb->flags |= EXTENT_BUFFER_FILLED; | |
2633 | ||
6af118ce CM |
2634 | spin_lock(&tree->buffer_lock); |
2635 | exists = buffer_tree_insert(tree, start, &eb->rb_node); | |
2636 | if (exists) { | |
2637 | /* add one reference for the caller */ | |
2638 | atomic_inc(&exists->refs); | |
2639 | spin_unlock(&tree->buffer_lock); | |
2640 | goto free_eb; | |
2641 | } | |
2642 | spin_unlock(&tree->buffer_lock); | |
2643 | ||
2644 | /* add one reference for the tree */ | |
2645 | atomic_inc(&eb->refs); | |
d1310b2e CM |
2646 | return eb; |
2647 | ||
6af118ce | 2648 | free_eb: |
d1310b2e | 2649 | if (!atomic_dec_and_test(&eb->refs)) |
6af118ce CM |
2650 | return exists; |
2651 | for (index = 1; index < i; index++) | |
d1310b2e | 2652 | page_cache_release(extent_buffer_page(eb, index)); |
6af118ce | 2653 | page_cache_release(extent_buffer_page(eb, 0)); |
d1310b2e | 2654 | __free_extent_buffer(eb); |
6af118ce | 2655 | return exists; |
d1310b2e CM |
2656 | } |
2657 | EXPORT_SYMBOL(alloc_extent_buffer); | |
2658 | ||
2659 | struct extent_buffer *find_extent_buffer(struct extent_io_tree *tree, | |
2660 | u64 start, unsigned long len, | |
2661 | gfp_t mask) | |
2662 | { | |
d1310b2e | 2663 | struct extent_buffer *eb; |
d1310b2e | 2664 | |
6af118ce CM |
2665 | spin_lock(&tree->buffer_lock); |
2666 | eb = buffer_search(tree, start); | |
2667 | if (eb) | |
2668 | atomic_inc(&eb->refs); | |
2669 | spin_unlock(&tree->buffer_lock); | |
d1310b2e | 2670 | |
0f9dd46c JB |
2671 | if (eb) |
2672 | mark_page_accessed(eb->first_page); | |
2673 | ||
d1310b2e | 2674 | return eb; |
d1310b2e CM |
2675 | } |
2676 | EXPORT_SYMBOL(find_extent_buffer); | |
2677 | ||
2678 | void free_extent_buffer(struct extent_buffer *eb) | |
2679 | { | |
d1310b2e CM |
2680 | if (!eb) |
2681 | return; | |
2682 | ||
2683 | if (!atomic_dec_and_test(&eb->refs)) | |
2684 | return; | |
2685 | ||
6af118ce | 2686 | WARN_ON(1); |
d1310b2e CM |
2687 | } |
2688 | EXPORT_SYMBOL(free_extent_buffer); | |
2689 | ||
2690 | int clear_extent_buffer_dirty(struct extent_io_tree *tree, | |
2691 | struct extent_buffer *eb) | |
2692 | { | |
2693 | int set; | |
2694 | unsigned long i; | |
2695 | unsigned long num_pages; | |
2696 | struct page *page; | |
2697 | ||
2698 | u64 start = eb->start; | |
2699 | u64 end = start + eb->len - 1; | |
2700 | ||
2701 | set = clear_extent_dirty(tree, start, end, GFP_NOFS); | |
2702 | num_pages = num_extent_pages(eb->start, eb->len); | |
2703 | ||
2704 | for (i = 0; i < num_pages; i++) { | |
2705 | page = extent_buffer_page(eb, i); | |
a61e6f29 | 2706 | lock_page(page); |
d1310b2e CM |
2707 | if (i == 0) |
2708 | set_page_extent_head(page, eb->len); | |
2709 | else | |
2710 | set_page_private(page, EXTENT_PAGE_PRIVATE); | |
2711 | ||
2712 | /* | |
2713 | * if we're on the last page or the first page and the | |
2714 | * block isn't aligned on a page boundary, do extra checks | |
2715 | * to make sure we don't clean page that is partially dirty | |
2716 | */ | |
2717 | if ((i == 0 && (eb->start & (PAGE_CACHE_SIZE - 1))) || | |
2718 | ((i == num_pages - 1) && | |
2719 | ((eb->start + eb->len) & (PAGE_CACHE_SIZE - 1)))) { | |
2720 | start = (u64)page->index << PAGE_CACHE_SHIFT; | |
2721 | end = start + PAGE_CACHE_SIZE - 1; | |
2722 | if (test_range_bit(tree, start, end, | |
2723 | EXTENT_DIRTY, 0)) { | |
a61e6f29 | 2724 | unlock_page(page); |
d1310b2e CM |
2725 | continue; |
2726 | } | |
2727 | } | |
2728 | clear_page_dirty_for_io(page); | |
0ee0fda0 | 2729 | spin_lock_irq(&page->mapping->tree_lock); |
d1310b2e CM |
2730 | if (!PageDirty(page)) { |
2731 | radix_tree_tag_clear(&page->mapping->page_tree, | |
2732 | page_index(page), | |
2733 | PAGECACHE_TAG_DIRTY); | |
2734 | } | |
0ee0fda0 | 2735 | spin_unlock_irq(&page->mapping->tree_lock); |
a61e6f29 | 2736 | unlock_page(page); |
d1310b2e CM |
2737 | } |
2738 | return 0; | |
2739 | } | |
2740 | EXPORT_SYMBOL(clear_extent_buffer_dirty); | |
2741 | ||
2742 | int wait_on_extent_buffer_writeback(struct extent_io_tree *tree, | |
2743 | struct extent_buffer *eb) | |
2744 | { | |
2745 | return wait_on_extent_writeback(tree, eb->start, | |
2746 | eb->start + eb->len - 1); | |
2747 | } | |
2748 | EXPORT_SYMBOL(wait_on_extent_buffer_writeback); | |
2749 | ||
2750 | int set_extent_buffer_dirty(struct extent_io_tree *tree, | |
2751 | struct extent_buffer *eb) | |
2752 | { | |
2753 | unsigned long i; | |
2754 | unsigned long num_pages; | |
2755 | ||
2756 | num_pages = num_extent_pages(eb->start, eb->len); | |
2757 | for (i = 0; i < num_pages; i++) { | |
2758 | struct page *page = extent_buffer_page(eb, i); | |
2759 | /* writepage may need to do something special for the | |
2760 | * first page, we have to make sure page->private is | |
2761 | * properly set. releasepage may drop page->private | |
2762 | * on us if the page isn't already dirty. | |
2763 | */ | |
a1b32a59 | 2764 | lock_page(page); |
d1310b2e | 2765 | if (i == 0) { |
d1310b2e CM |
2766 | set_page_extent_head(page, eb->len); |
2767 | } else if (PagePrivate(page) && | |
2768 | page->private != EXTENT_PAGE_PRIVATE) { | |
d1310b2e | 2769 | set_page_extent_mapped(page); |
d1310b2e CM |
2770 | } |
2771 | __set_page_dirty_nobuffers(extent_buffer_page(eb, i)); | |
a1b32a59 CM |
2772 | set_extent_dirty(tree, page_offset(page), |
2773 | page_offset(page) + PAGE_CACHE_SIZE -1, | |
2774 | GFP_NOFS); | |
2775 | unlock_page(page); | |
d1310b2e | 2776 | } |
a1b32a59 | 2777 | return 0; |
d1310b2e CM |
2778 | } |
2779 | EXPORT_SYMBOL(set_extent_buffer_dirty); | |
2780 | ||
1259ab75 CM |
2781 | int clear_extent_buffer_uptodate(struct extent_io_tree *tree, |
2782 | struct extent_buffer *eb) | |
2783 | { | |
2784 | unsigned long i; | |
2785 | struct page *page; | |
2786 | unsigned long num_pages; | |
2787 | ||
2788 | num_pages = num_extent_pages(eb->start, eb->len); | |
2789 | eb->flags &= ~EXTENT_UPTODATE; | |
2790 | ||
2791 | clear_extent_uptodate(tree, eb->start, eb->start + eb->len - 1, | |
2792 | GFP_NOFS); | |
2793 | for (i = 0; i < num_pages; i++) { | |
2794 | page = extent_buffer_page(eb, i); | |
33958dc6 CM |
2795 | if (page) |
2796 | ClearPageUptodate(page); | |
1259ab75 CM |
2797 | } |
2798 | return 0; | |
2799 | } | |
2800 | ||
d1310b2e CM |
2801 | int set_extent_buffer_uptodate(struct extent_io_tree *tree, |
2802 | struct extent_buffer *eb) | |
2803 | { | |
2804 | unsigned long i; | |
2805 | struct page *page; | |
2806 | unsigned long num_pages; | |
2807 | ||
2808 | num_pages = num_extent_pages(eb->start, eb->len); | |
2809 | ||
2810 | set_extent_uptodate(tree, eb->start, eb->start + eb->len - 1, | |
2811 | GFP_NOFS); | |
2812 | for (i = 0; i < num_pages; i++) { | |
2813 | page = extent_buffer_page(eb, i); | |
2814 | if ((i == 0 && (eb->start & (PAGE_CACHE_SIZE - 1))) || | |
2815 | ((i == num_pages - 1) && | |
2816 | ((eb->start + eb->len) & (PAGE_CACHE_SIZE - 1)))) { | |
2817 | check_page_uptodate(tree, page); | |
2818 | continue; | |
2819 | } | |
2820 | SetPageUptodate(page); | |
2821 | } | |
2822 | return 0; | |
2823 | } | |
2824 | EXPORT_SYMBOL(set_extent_buffer_uptodate); | |
2825 | ||
ce9adaa5 CM |
2826 | int extent_range_uptodate(struct extent_io_tree *tree, |
2827 | u64 start, u64 end) | |
2828 | { | |
2829 | struct page *page; | |
2830 | int ret; | |
2831 | int pg_uptodate = 1; | |
2832 | int uptodate; | |
2833 | unsigned long index; | |
2834 | ||
2835 | ret = test_range_bit(tree, start, end, EXTENT_UPTODATE, 1); | |
2836 | if (ret) | |
2837 | return 1; | |
2838 | while(start <= end) { | |
2839 | index = start >> PAGE_CACHE_SHIFT; | |
2840 | page = find_get_page(tree->mapping, index); | |
2841 | uptodate = PageUptodate(page); | |
2842 | page_cache_release(page); | |
2843 | if (!uptodate) { | |
2844 | pg_uptodate = 0; | |
2845 | break; | |
2846 | } | |
2847 | start += PAGE_CACHE_SIZE; | |
2848 | } | |
2849 | return pg_uptodate; | |
2850 | } | |
2851 | ||
d1310b2e | 2852 | int extent_buffer_uptodate(struct extent_io_tree *tree, |
ce9adaa5 | 2853 | struct extent_buffer *eb) |
d1310b2e | 2854 | { |
728131d8 | 2855 | int ret = 0; |
ce9adaa5 CM |
2856 | unsigned long num_pages; |
2857 | unsigned long i; | |
728131d8 CM |
2858 | struct page *page; |
2859 | int pg_uptodate = 1; | |
2860 | ||
d1310b2e | 2861 | if (eb->flags & EXTENT_UPTODATE) |
4235298e | 2862 | return 1; |
728131d8 | 2863 | |
4235298e | 2864 | ret = test_range_bit(tree, eb->start, eb->start + eb->len - 1, |
d1310b2e | 2865 | EXTENT_UPTODATE, 1); |
4235298e CM |
2866 | if (ret) |
2867 | return ret; | |
728131d8 CM |
2868 | |
2869 | num_pages = num_extent_pages(eb->start, eb->len); | |
2870 | for (i = 0; i < num_pages; i++) { | |
2871 | page = extent_buffer_page(eb, i); | |
2872 | if (!PageUptodate(page)) { | |
2873 | pg_uptodate = 0; | |
2874 | break; | |
2875 | } | |
2876 | } | |
4235298e | 2877 | return pg_uptodate; |
d1310b2e CM |
2878 | } |
2879 | EXPORT_SYMBOL(extent_buffer_uptodate); | |
2880 | ||
2881 | int read_extent_buffer_pages(struct extent_io_tree *tree, | |
2882 | struct extent_buffer *eb, | |
a86c12c7 | 2883 | u64 start, int wait, |
f188591e | 2884 | get_extent_t *get_extent, int mirror_num) |
d1310b2e CM |
2885 | { |
2886 | unsigned long i; | |
2887 | unsigned long start_i; | |
2888 | struct page *page; | |
2889 | int err; | |
2890 | int ret = 0; | |
ce9adaa5 CM |
2891 | int locked_pages = 0; |
2892 | int all_uptodate = 1; | |
2893 | int inc_all_pages = 0; | |
d1310b2e | 2894 | unsigned long num_pages; |
a86c12c7 CM |
2895 | struct bio *bio = NULL; |
2896 | ||
d1310b2e CM |
2897 | if (eb->flags & EXTENT_UPTODATE) |
2898 | return 0; | |
2899 | ||
ce9adaa5 | 2900 | if (test_range_bit(tree, eb->start, eb->start + eb->len - 1, |
d1310b2e CM |
2901 | EXTENT_UPTODATE, 1)) { |
2902 | return 0; | |
2903 | } | |
2904 | ||
2905 | if (start) { | |
2906 | WARN_ON(start < eb->start); | |
2907 | start_i = (start >> PAGE_CACHE_SHIFT) - | |
2908 | (eb->start >> PAGE_CACHE_SHIFT); | |
2909 | } else { | |
2910 | start_i = 0; | |
2911 | } | |
2912 | ||
2913 | num_pages = num_extent_pages(eb->start, eb->len); | |
2914 | for (i = start_i; i < num_pages; i++) { | |
2915 | page = extent_buffer_page(eb, i); | |
d1310b2e | 2916 | if (!wait) { |
2db04966 | 2917 | if (!trylock_page(page)) |
ce9adaa5 | 2918 | goto unlock_exit; |
d1310b2e CM |
2919 | } else { |
2920 | lock_page(page); | |
2921 | } | |
ce9adaa5 | 2922 | locked_pages++; |
d1310b2e | 2923 | if (!PageUptodate(page)) { |
ce9adaa5 CM |
2924 | all_uptodate = 0; |
2925 | } | |
2926 | } | |
2927 | if (all_uptodate) { | |
2928 | if (start_i == 0) | |
2929 | eb->flags |= EXTENT_UPTODATE; | |
a1b32a59 CM |
2930 | if (ret) { |
2931 | printk("all up to date but ret is %d\n", ret); | |
2932 | } | |
ce9adaa5 CM |
2933 | goto unlock_exit; |
2934 | } | |
2935 | ||
2936 | for (i = start_i; i < num_pages; i++) { | |
2937 | page = extent_buffer_page(eb, i); | |
2938 | if (inc_all_pages) | |
2939 | page_cache_get(page); | |
2940 | if (!PageUptodate(page)) { | |
2941 | if (start_i == 0) | |
2942 | inc_all_pages = 1; | |
f188591e | 2943 | ClearPageError(page); |
a86c12c7 | 2944 | err = __extent_read_full_page(tree, page, |
f188591e CM |
2945 | get_extent, &bio, |
2946 | mirror_num); | |
d1310b2e CM |
2947 | if (err) { |
2948 | ret = err; | |
a1b32a59 | 2949 | printk("err %d from __extent_read_full_page\n", ret); |
d1310b2e CM |
2950 | } |
2951 | } else { | |
2952 | unlock_page(page); | |
2953 | } | |
2954 | } | |
2955 | ||
a86c12c7 | 2956 | if (bio) |
f188591e | 2957 | submit_one_bio(READ, bio, mirror_num); |
a86c12c7 | 2958 | |
d1310b2e | 2959 | if (ret || !wait) { |
a1b32a59 CM |
2960 | if (ret) |
2961 | printk("ret %d wait %d returning\n", ret, wait); | |
d1310b2e CM |
2962 | return ret; |
2963 | } | |
d1310b2e CM |
2964 | for (i = start_i; i < num_pages; i++) { |
2965 | page = extent_buffer_page(eb, i); | |
2966 | wait_on_page_locked(page); | |
2967 | if (!PageUptodate(page)) { | |
a1b32a59 | 2968 | printk("page not uptodate after wait_on_page_locked\n"); |
d1310b2e CM |
2969 | ret = -EIO; |
2970 | } | |
2971 | } | |
2972 | if (!ret) | |
2973 | eb->flags |= EXTENT_UPTODATE; | |
2974 | return ret; | |
ce9adaa5 CM |
2975 | |
2976 | unlock_exit: | |
2977 | i = start_i; | |
2978 | while(locked_pages > 0) { | |
2979 | page = extent_buffer_page(eb, i); | |
2980 | i++; | |
2981 | unlock_page(page); | |
2982 | locked_pages--; | |
2983 | } | |
2984 | return ret; | |
d1310b2e CM |
2985 | } |
2986 | EXPORT_SYMBOL(read_extent_buffer_pages); | |
2987 | ||
2988 | void read_extent_buffer(struct extent_buffer *eb, void *dstv, | |
2989 | unsigned long start, | |
2990 | unsigned long len) | |
2991 | { | |
2992 | size_t cur; | |
2993 | size_t offset; | |
2994 | struct page *page; | |
2995 | char *kaddr; | |
2996 | char *dst = (char *)dstv; | |
2997 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
2998 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
d1310b2e CM |
2999 | |
3000 | WARN_ON(start > eb->len); | |
3001 | WARN_ON(start + len > eb->start + eb->len); | |
3002 | ||
3003 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3004 | ||
3005 | while(len > 0) { | |
3006 | page = extent_buffer_page(eb, i); | |
d1310b2e CM |
3007 | |
3008 | cur = min(len, (PAGE_CACHE_SIZE - offset)); | |
3009 | kaddr = kmap_atomic(page, KM_USER1); | |
3010 | memcpy(dst, kaddr + offset, cur); | |
3011 | kunmap_atomic(kaddr, KM_USER1); | |
3012 | ||
3013 | dst += cur; | |
3014 | len -= cur; | |
3015 | offset = 0; | |
3016 | i++; | |
3017 | } | |
3018 | } | |
3019 | EXPORT_SYMBOL(read_extent_buffer); | |
3020 | ||
3021 | int map_private_extent_buffer(struct extent_buffer *eb, unsigned long start, | |
3022 | unsigned long min_len, char **token, char **map, | |
3023 | unsigned long *map_start, | |
3024 | unsigned long *map_len, int km) | |
3025 | { | |
3026 | size_t offset = start & (PAGE_CACHE_SIZE - 1); | |
3027 | char *kaddr; | |
3028 | struct page *p; | |
3029 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3030 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
3031 | unsigned long end_i = (start_offset + start + min_len - 1) >> | |
3032 | PAGE_CACHE_SHIFT; | |
3033 | ||
3034 | if (i != end_i) | |
3035 | return -EINVAL; | |
3036 | ||
3037 | if (i == 0) { | |
3038 | offset = start_offset; | |
3039 | *map_start = 0; | |
3040 | } else { | |
3041 | offset = 0; | |
3042 | *map_start = ((u64)i << PAGE_CACHE_SHIFT) - start_offset; | |
3043 | } | |
3044 | if (start + min_len > eb->len) { | |
3045 | printk("bad mapping eb start %Lu len %lu, wanted %lu %lu\n", eb->start, eb->len, start, min_len); | |
3046 | WARN_ON(1); | |
3047 | } | |
3048 | ||
3049 | p = extent_buffer_page(eb, i); | |
d1310b2e CM |
3050 | kaddr = kmap_atomic(p, km); |
3051 | *token = kaddr; | |
3052 | *map = kaddr + offset; | |
3053 | *map_len = PAGE_CACHE_SIZE - offset; | |
3054 | return 0; | |
3055 | } | |
3056 | EXPORT_SYMBOL(map_private_extent_buffer); | |
3057 | ||
3058 | int map_extent_buffer(struct extent_buffer *eb, unsigned long start, | |
3059 | unsigned long min_len, | |
3060 | char **token, char **map, | |
3061 | unsigned long *map_start, | |
3062 | unsigned long *map_len, int km) | |
3063 | { | |
3064 | int err; | |
3065 | int save = 0; | |
3066 | if (eb->map_token) { | |
3067 | unmap_extent_buffer(eb, eb->map_token, km); | |
3068 | eb->map_token = NULL; | |
3069 | save = 1; | |
3070 | } | |
3071 | err = map_private_extent_buffer(eb, start, min_len, token, map, | |
3072 | map_start, map_len, km); | |
3073 | if (!err && save) { | |
3074 | eb->map_token = *token; | |
3075 | eb->kaddr = *map; | |
3076 | eb->map_start = *map_start; | |
3077 | eb->map_len = *map_len; | |
3078 | } | |
3079 | return err; | |
3080 | } | |
3081 | EXPORT_SYMBOL(map_extent_buffer); | |
3082 | ||
3083 | void unmap_extent_buffer(struct extent_buffer *eb, char *token, int km) | |
3084 | { | |
3085 | kunmap_atomic(token, km); | |
3086 | } | |
3087 | EXPORT_SYMBOL(unmap_extent_buffer); | |
3088 | ||
3089 | int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv, | |
3090 | unsigned long start, | |
3091 | unsigned long len) | |
3092 | { | |
3093 | size_t cur; | |
3094 | size_t offset; | |
3095 | struct page *page; | |
3096 | char *kaddr; | |
3097 | char *ptr = (char *)ptrv; | |
3098 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3099 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
3100 | int ret = 0; | |
3101 | ||
3102 | WARN_ON(start > eb->len); | |
3103 | WARN_ON(start + len > eb->start + eb->len); | |
3104 | ||
3105 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3106 | ||
3107 | while(len > 0) { | |
3108 | page = extent_buffer_page(eb, i); | |
d1310b2e CM |
3109 | |
3110 | cur = min(len, (PAGE_CACHE_SIZE - offset)); | |
3111 | ||
3112 | kaddr = kmap_atomic(page, KM_USER0); | |
3113 | ret = memcmp(ptr, kaddr + offset, cur); | |
3114 | kunmap_atomic(kaddr, KM_USER0); | |
3115 | if (ret) | |
3116 | break; | |
3117 | ||
3118 | ptr += cur; | |
3119 | len -= cur; | |
3120 | offset = 0; | |
3121 | i++; | |
3122 | } | |
3123 | return ret; | |
3124 | } | |
3125 | EXPORT_SYMBOL(memcmp_extent_buffer); | |
3126 | ||
3127 | void write_extent_buffer(struct extent_buffer *eb, const void *srcv, | |
3128 | unsigned long start, unsigned long len) | |
3129 | { | |
3130 | size_t cur; | |
3131 | size_t offset; | |
3132 | struct page *page; | |
3133 | char *kaddr; | |
3134 | char *src = (char *)srcv; | |
3135 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3136 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
3137 | ||
3138 | WARN_ON(start > eb->len); | |
3139 | WARN_ON(start + len > eb->start + eb->len); | |
3140 | ||
3141 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3142 | ||
3143 | while(len > 0) { | |
3144 | page = extent_buffer_page(eb, i); | |
3145 | WARN_ON(!PageUptodate(page)); | |
3146 | ||
3147 | cur = min(len, PAGE_CACHE_SIZE - offset); | |
3148 | kaddr = kmap_atomic(page, KM_USER1); | |
3149 | memcpy(kaddr + offset, src, cur); | |
3150 | kunmap_atomic(kaddr, KM_USER1); | |
3151 | ||
3152 | src += cur; | |
3153 | len -= cur; | |
3154 | offset = 0; | |
3155 | i++; | |
3156 | } | |
3157 | } | |
3158 | EXPORT_SYMBOL(write_extent_buffer); | |
3159 | ||
3160 | void memset_extent_buffer(struct extent_buffer *eb, char c, | |
3161 | unsigned long start, unsigned long len) | |
3162 | { | |
3163 | size_t cur; | |
3164 | size_t offset; | |
3165 | struct page *page; | |
3166 | char *kaddr; | |
3167 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3168 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
3169 | ||
3170 | WARN_ON(start > eb->len); | |
3171 | WARN_ON(start + len > eb->start + eb->len); | |
3172 | ||
3173 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3174 | ||
3175 | while(len > 0) { | |
3176 | page = extent_buffer_page(eb, i); | |
3177 | WARN_ON(!PageUptodate(page)); | |
3178 | ||
3179 | cur = min(len, PAGE_CACHE_SIZE - offset); | |
3180 | kaddr = kmap_atomic(page, KM_USER0); | |
3181 | memset(kaddr + offset, c, cur); | |
3182 | kunmap_atomic(kaddr, KM_USER0); | |
3183 | ||
3184 | len -= cur; | |
3185 | offset = 0; | |
3186 | i++; | |
3187 | } | |
3188 | } | |
3189 | EXPORT_SYMBOL(memset_extent_buffer); | |
3190 | ||
3191 | void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src, | |
3192 | unsigned long dst_offset, unsigned long src_offset, | |
3193 | unsigned long len) | |
3194 | { | |
3195 | u64 dst_len = dst->len; | |
3196 | size_t cur; | |
3197 | size_t offset; | |
3198 | struct page *page; | |
3199 | char *kaddr; | |
3200 | size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3201 | unsigned long i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT; | |
3202 | ||
3203 | WARN_ON(src->len != dst_len); | |
3204 | ||
3205 | offset = (start_offset + dst_offset) & | |
3206 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3207 | ||
3208 | while(len > 0) { | |
3209 | page = extent_buffer_page(dst, i); | |
3210 | WARN_ON(!PageUptodate(page)); | |
3211 | ||
3212 | cur = min(len, (unsigned long)(PAGE_CACHE_SIZE - offset)); | |
3213 | ||
3214 | kaddr = kmap_atomic(page, KM_USER0); | |
3215 | read_extent_buffer(src, kaddr + offset, src_offset, cur); | |
3216 | kunmap_atomic(kaddr, KM_USER0); | |
3217 | ||
3218 | src_offset += cur; | |
3219 | len -= cur; | |
3220 | offset = 0; | |
3221 | i++; | |
3222 | } | |
3223 | } | |
3224 | EXPORT_SYMBOL(copy_extent_buffer); | |
3225 | ||
3226 | static void move_pages(struct page *dst_page, struct page *src_page, | |
3227 | unsigned long dst_off, unsigned long src_off, | |
3228 | unsigned long len) | |
3229 | { | |
3230 | char *dst_kaddr = kmap_atomic(dst_page, KM_USER0); | |
3231 | if (dst_page == src_page) { | |
3232 | memmove(dst_kaddr + dst_off, dst_kaddr + src_off, len); | |
3233 | } else { | |
3234 | char *src_kaddr = kmap_atomic(src_page, KM_USER1); | |
3235 | char *p = dst_kaddr + dst_off + len; | |
3236 | char *s = src_kaddr + src_off + len; | |
3237 | ||
3238 | while (len--) | |
3239 | *--p = *--s; | |
3240 | ||
3241 | kunmap_atomic(src_kaddr, KM_USER1); | |
3242 | } | |
3243 | kunmap_atomic(dst_kaddr, KM_USER0); | |
3244 | } | |
3245 | ||
3246 | static void copy_pages(struct page *dst_page, struct page *src_page, | |
3247 | unsigned long dst_off, unsigned long src_off, | |
3248 | unsigned long len) | |
3249 | { | |
3250 | char *dst_kaddr = kmap_atomic(dst_page, KM_USER0); | |
3251 | char *src_kaddr; | |
3252 | ||
3253 | if (dst_page != src_page) | |
3254 | src_kaddr = kmap_atomic(src_page, KM_USER1); | |
3255 | else | |
3256 | src_kaddr = dst_kaddr; | |
3257 | ||
3258 | memcpy(dst_kaddr + dst_off, src_kaddr + src_off, len); | |
3259 | kunmap_atomic(dst_kaddr, KM_USER0); | |
3260 | if (dst_page != src_page) | |
3261 | kunmap_atomic(src_kaddr, KM_USER1); | |
3262 | } | |
3263 | ||
3264 | void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, | |
3265 | unsigned long src_offset, unsigned long len) | |
3266 | { | |
3267 | size_t cur; | |
3268 | size_t dst_off_in_page; | |
3269 | size_t src_off_in_page; | |
3270 | size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3271 | unsigned long dst_i; | |
3272 | unsigned long src_i; | |
3273 | ||
3274 | if (src_offset + len > dst->len) { | |
3275 | printk("memmove bogus src_offset %lu move len %lu len %lu\n", | |
3276 | src_offset, len, dst->len); | |
3277 | BUG_ON(1); | |
3278 | } | |
3279 | if (dst_offset + len > dst->len) { | |
3280 | printk("memmove bogus dst_offset %lu move len %lu len %lu\n", | |
3281 | dst_offset, len, dst->len); | |
3282 | BUG_ON(1); | |
3283 | } | |
3284 | ||
3285 | while(len > 0) { | |
3286 | dst_off_in_page = (start_offset + dst_offset) & | |
3287 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3288 | src_off_in_page = (start_offset + src_offset) & | |
3289 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3290 | ||
3291 | dst_i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT; | |
3292 | src_i = (start_offset + src_offset) >> PAGE_CACHE_SHIFT; | |
3293 | ||
3294 | cur = min(len, (unsigned long)(PAGE_CACHE_SIZE - | |
3295 | src_off_in_page)); | |
3296 | cur = min_t(unsigned long, cur, | |
3297 | (unsigned long)(PAGE_CACHE_SIZE - dst_off_in_page)); | |
3298 | ||
3299 | copy_pages(extent_buffer_page(dst, dst_i), | |
3300 | extent_buffer_page(dst, src_i), | |
3301 | dst_off_in_page, src_off_in_page, cur); | |
3302 | ||
3303 | src_offset += cur; | |
3304 | dst_offset += cur; | |
3305 | len -= cur; | |
3306 | } | |
3307 | } | |
3308 | EXPORT_SYMBOL(memcpy_extent_buffer); | |
3309 | ||
3310 | void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, | |
3311 | unsigned long src_offset, unsigned long len) | |
3312 | { | |
3313 | size_t cur; | |
3314 | size_t dst_off_in_page; | |
3315 | size_t src_off_in_page; | |
3316 | unsigned long dst_end = dst_offset + len - 1; | |
3317 | unsigned long src_end = src_offset + len - 1; | |
3318 | size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3319 | unsigned long dst_i; | |
3320 | unsigned long src_i; | |
3321 | ||
3322 | if (src_offset + len > dst->len) { | |
3323 | printk("memmove bogus src_offset %lu move len %lu len %lu\n", | |
3324 | src_offset, len, dst->len); | |
3325 | BUG_ON(1); | |
3326 | } | |
3327 | if (dst_offset + len > dst->len) { | |
3328 | printk("memmove bogus dst_offset %lu move len %lu len %lu\n", | |
3329 | dst_offset, len, dst->len); | |
3330 | BUG_ON(1); | |
3331 | } | |
3332 | if (dst_offset < src_offset) { | |
3333 | memcpy_extent_buffer(dst, dst_offset, src_offset, len); | |
3334 | return; | |
3335 | } | |
3336 | while(len > 0) { | |
3337 | dst_i = (start_offset + dst_end) >> PAGE_CACHE_SHIFT; | |
3338 | src_i = (start_offset + src_end) >> PAGE_CACHE_SHIFT; | |
3339 | ||
3340 | dst_off_in_page = (start_offset + dst_end) & | |
3341 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3342 | src_off_in_page = (start_offset + src_end) & | |
3343 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3344 | ||
3345 | cur = min_t(unsigned long, len, src_off_in_page + 1); | |
3346 | cur = min(cur, dst_off_in_page + 1); | |
3347 | move_pages(extent_buffer_page(dst, dst_i), | |
3348 | extent_buffer_page(dst, src_i), | |
3349 | dst_off_in_page - cur + 1, | |
3350 | src_off_in_page - cur + 1, cur); | |
3351 | ||
3352 | dst_end -= cur; | |
3353 | src_end -= cur; | |
3354 | len -= cur; | |
3355 | } | |
3356 | } | |
3357 | EXPORT_SYMBOL(memmove_extent_buffer); | |
6af118ce CM |
3358 | |
3359 | int try_release_extent_buffer(struct extent_io_tree *tree, struct page *page) | |
3360 | { | |
3361 | u64 start = page_offset(page); | |
3362 | struct extent_buffer *eb; | |
3363 | int ret = 1; | |
3364 | unsigned long i; | |
3365 | unsigned long num_pages; | |
3366 | ||
3367 | spin_lock(&tree->buffer_lock); | |
3368 | eb = buffer_search(tree, start); | |
3369 | if (!eb) | |
3370 | goto out; | |
3371 | ||
3372 | if (atomic_read(&eb->refs) > 1) { | |
3373 | ret = 0; | |
3374 | goto out; | |
3375 | } | |
3376 | /* at this point we can safely release the extent buffer */ | |
3377 | num_pages = num_extent_pages(eb->start, eb->len); | |
b214107e CH |
3378 | for (i = 0; i < num_pages; i++) |
3379 | page_cache_release(extent_buffer_page(eb, i)); | |
6af118ce CM |
3380 | rb_erase(&eb->rb_node, &tree->buffer); |
3381 | __free_extent_buffer(eb); | |
3382 | out: | |
3383 | spin_unlock(&tree->buffer_lock); | |
3384 | return ret; | |
3385 | } | |
3386 | EXPORT_SYMBOL(try_release_extent_buffer); |