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> | |
d1310b2e CM |
5 | #include <linux/pagemap.h> |
6 | #include <linux/page-flags.h> | |
7 | #include <linux/module.h> | |
8 | #include <linux/spinlock.h> | |
9 | #include <linux/blkdev.h> | |
10 | #include <linux/swap.h> | |
d1310b2e CM |
11 | #include <linux/writeback.h> |
12 | #include <linux/pagevec.h> | |
13 | #include "extent_io.h" | |
14 | #include "extent_map.h" | |
2db04966 | 15 | #include "compat.h" |
902b22f3 DW |
16 | #include "ctree.h" |
17 | #include "btrfs_inode.h" | |
d1310b2e | 18 | |
d1310b2e CM |
19 | static struct kmem_cache *extent_state_cache; |
20 | static struct kmem_cache *extent_buffer_cache; | |
21 | ||
22 | static LIST_HEAD(buffers); | |
23 | static LIST_HEAD(states); | |
4bef0848 | 24 | |
b47eda86 | 25 | #define LEAK_DEBUG 0 |
3935127c | 26 | #if LEAK_DEBUG |
d397712b | 27 | static DEFINE_SPINLOCK(leak_lock); |
4bef0848 | 28 | #endif |
d1310b2e | 29 | |
d1310b2e CM |
30 | #define BUFFER_LRU_MAX 64 |
31 | ||
32 | struct tree_entry { | |
33 | u64 start; | |
34 | u64 end; | |
d1310b2e CM |
35 | struct rb_node rb_node; |
36 | }; | |
37 | ||
38 | struct extent_page_data { | |
39 | struct bio *bio; | |
40 | struct extent_io_tree *tree; | |
41 | get_extent_t *get_extent; | |
771ed689 CM |
42 | |
43 | /* tells writepage not to lock the state bits for this range | |
44 | * it still does the unlocking | |
45 | */ | |
ffbd517d CM |
46 | unsigned int extent_locked:1; |
47 | ||
48 | /* tells the submit_bio code to use a WRITE_SYNC */ | |
49 | unsigned int sync_io:1; | |
d1310b2e CM |
50 | }; |
51 | ||
52 | int __init extent_io_init(void) | |
53 | { | |
9601e3f6 CH |
54 | extent_state_cache = kmem_cache_create("extent_state", |
55 | sizeof(struct extent_state), 0, | |
56 | SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL); | |
d1310b2e CM |
57 | if (!extent_state_cache) |
58 | return -ENOMEM; | |
59 | ||
9601e3f6 CH |
60 | extent_buffer_cache = kmem_cache_create("extent_buffers", |
61 | sizeof(struct extent_buffer), 0, | |
62 | SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL); | |
d1310b2e CM |
63 | if (!extent_buffer_cache) |
64 | goto free_state_cache; | |
65 | return 0; | |
66 | ||
67 | free_state_cache: | |
68 | kmem_cache_destroy(extent_state_cache); | |
69 | return -ENOMEM; | |
70 | } | |
71 | ||
72 | void extent_io_exit(void) | |
73 | { | |
74 | struct extent_state *state; | |
2d2ae547 | 75 | struct extent_buffer *eb; |
d1310b2e CM |
76 | |
77 | while (!list_empty(&states)) { | |
2d2ae547 | 78 | state = list_entry(states.next, struct extent_state, leak_list); |
d397712b CM |
79 | printk(KERN_ERR "btrfs state leak: start %llu end %llu " |
80 | "state %lu in tree %p refs %d\n", | |
81 | (unsigned long long)state->start, | |
82 | (unsigned long long)state->end, | |
83 | state->state, state->tree, atomic_read(&state->refs)); | |
2d2ae547 | 84 | list_del(&state->leak_list); |
d1310b2e CM |
85 | kmem_cache_free(extent_state_cache, state); |
86 | ||
87 | } | |
88 | ||
2d2ae547 CM |
89 | while (!list_empty(&buffers)) { |
90 | eb = list_entry(buffers.next, struct extent_buffer, leak_list); | |
d397712b CM |
91 | printk(KERN_ERR "btrfs buffer leak start %llu len %lu " |
92 | "refs %d\n", (unsigned long long)eb->start, | |
93 | eb->len, atomic_read(&eb->refs)); | |
2d2ae547 CM |
94 | list_del(&eb->leak_list); |
95 | kmem_cache_free(extent_buffer_cache, eb); | |
96 | } | |
d1310b2e CM |
97 | if (extent_state_cache) |
98 | kmem_cache_destroy(extent_state_cache); | |
99 | if (extent_buffer_cache) | |
100 | kmem_cache_destroy(extent_buffer_cache); | |
101 | } | |
102 | ||
103 | void extent_io_tree_init(struct extent_io_tree *tree, | |
f993c883 | 104 | struct address_space *mapping) |
d1310b2e | 105 | { |
6bef4d31 | 106 | tree->state = RB_ROOT; |
19fe0a8b | 107 | INIT_RADIX_TREE(&tree->buffer, GFP_ATOMIC); |
d1310b2e CM |
108 | tree->ops = NULL; |
109 | tree->dirty_bytes = 0; | |
70dec807 | 110 | spin_lock_init(&tree->lock); |
6af118ce | 111 | spin_lock_init(&tree->buffer_lock); |
d1310b2e | 112 | tree->mapping = mapping; |
d1310b2e | 113 | } |
d1310b2e | 114 | |
b2950863 | 115 | static struct extent_state *alloc_extent_state(gfp_t mask) |
d1310b2e CM |
116 | { |
117 | struct extent_state *state; | |
3935127c | 118 | #if LEAK_DEBUG |
2d2ae547 | 119 | unsigned long flags; |
4bef0848 | 120 | #endif |
d1310b2e CM |
121 | |
122 | state = kmem_cache_alloc(extent_state_cache, mask); | |
2b114d1d | 123 | if (!state) |
d1310b2e CM |
124 | return state; |
125 | state->state = 0; | |
d1310b2e | 126 | state->private = 0; |
70dec807 | 127 | state->tree = NULL; |
3935127c | 128 | #if LEAK_DEBUG |
2d2ae547 CM |
129 | spin_lock_irqsave(&leak_lock, flags); |
130 | list_add(&state->leak_list, &states); | |
131 | spin_unlock_irqrestore(&leak_lock, flags); | |
4bef0848 | 132 | #endif |
d1310b2e CM |
133 | atomic_set(&state->refs, 1); |
134 | init_waitqueue_head(&state->wq); | |
135 | return state; | |
136 | } | |
d1310b2e | 137 | |
4845e44f | 138 | void free_extent_state(struct extent_state *state) |
d1310b2e | 139 | { |
d1310b2e CM |
140 | if (!state) |
141 | return; | |
142 | if (atomic_dec_and_test(&state->refs)) { | |
3935127c | 143 | #if LEAK_DEBUG |
2d2ae547 | 144 | unsigned long flags; |
4bef0848 | 145 | #endif |
70dec807 | 146 | WARN_ON(state->tree); |
3935127c | 147 | #if LEAK_DEBUG |
2d2ae547 CM |
148 | spin_lock_irqsave(&leak_lock, flags); |
149 | list_del(&state->leak_list); | |
150 | spin_unlock_irqrestore(&leak_lock, flags); | |
4bef0848 | 151 | #endif |
d1310b2e CM |
152 | kmem_cache_free(extent_state_cache, state); |
153 | } | |
154 | } | |
d1310b2e CM |
155 | |
156 | static struct rb_node *tree_insert(struct rb_root *root, u64 offset, | |
157 | struct rb_node *node) | |
158 | { | |
d397712b CM |
159 | struct rb_node **p = &root->rb_node; |
160 | struct rb_node *parent = NULL; | |
d1310b2e CM |
161 | struct tree_entry *entry; |
162 | ||
d397712b | 163 | while (*p) { |
d1310b2e CM |
164 | parent = *p; |
165 | entry = rb_entry(parent, struct tree_entry, rb_node); | |
166 | ||
167 | if (offset < entry->start) | |
168 | p = &(*p)->rb_left; | |
169 | else if (offset > entry->end) | |
170 | p = &(*p)->rb_right; | |
171 | else | |
172 | return parent; | |
173 | } | |
174 | ||
175 | entry = rb_entry(node, struct tree_entry, rb_node); | |
d1310b2e CM |
176 | rb_link_node(node, parent, p); |
177 | rb_insert_color(node, root); | |
178 | return NULL; | |
179 | } | |
180 | ||
80ea96b1 | 181 | static struct rb_node *__etree_search(struct extent_io_tree *tree, u64 offset, |
d1310b2e CM |
182 | struct rb_node **prev_ret, |
183 | struct rb_node **next_ret) | |
184 | { | |
80ea96b1 | 185 | struct rb_root *root = &tree->state; |
d397712b | 186 | struct rb_node *n = root->rb_node; |
d1310b2e CM |
187 | struct rb_node *prev = NULL; |
188 | struct rb_node *orig_prev = NULL; | |
189 | struct tree_entry *entry; | |
190 | struct tree_entry *prev_entry = NULL; | |
191 | ||
d397712b | 192 | while (n) { |
d1310b2e CM |
193 | entry = rb_entry(n, struct tree_entry, rb_node); |
194 | prev = n; | |
195 | prev_entry = entry; | |
196 | ||
197 | if (offset < entry->start) | |
198 | n = n->rb_left; | |
199 | else if (offset > entry->end) | |
200 | n = n->rb_right; | |
d397712b | 201 | else |
d1310b2e CM |
202 | return n; |
203 | } | |
204 | ||
205 | if (prev_ret) { | |
206 | orig_prev = prev; | |
d397712b | 207 | while (prev && offset > prev_entry->end) { |
d1310b2e CM |
208 | prev = rb_next(prev); |
209 | prev_entry = rb_entry(prev, struct tree_entry, rb_node); | |
210 | } | |
211 | *prev_ret = prev; | |
212 | prev = orig_prev; | |
213 | } | |
214 | ||
215 | if (next_ret) { | |
216 | prev_entry = rb_entry(prev, struct tree_entry, rb_node); | |
d397712b | 217 | while (prev && offset < prev_entry->start) { |
d1310b2e CM |
218 | prev = rb_prev(prev); |
219 | prev_entry = rb_entry(prev, struct tree_entry, rb_node); | |
220 | } | |
221 | *next_ret = prev; | |
222 | } | |
223 | return NULL; | |
224 | } | |
225 | ||
80ea96b1 CM |
226 | static inline struct rb_node *tree_search(struct extent_io_tree *tree, |
227 | u64 offset) | |
d1310b2e | 228 | { |
70dec807 | 229 | struct rb_node *prev = NULL; |
d1310b2e | 230 | struct rb_node *ret; |
70dec807 | 231 | |
80ea96b1 | 232 | ret = __etree_search(tree, offset, &prev, NULL); |
d397712b | 233 | if (!ret) |
d1310b2e CM |
234 | return prev; |
235 | return ret; | |
236 | } | |
237 | ||
9ed74f2d JB |
238 | static void merge_cb(struct extent_io_tree *tree, struct extent_state *new, |
239 | struct extent_state *other) | |
240 | { | |
241 | if (tree->ops && tree->ops->merge_extent_hook) | |
242 | tree->ops->merge_extent_hook(tree->mapping->host, new, | |
243 | other); | |
244 | } | |
245 | ||
d1310b2e CM |
246 | /* |
247 | * utility function to look for merge candidates inside a given range. | |
248 | * Any extents with matching state are merged together into a single | |
249 | * extent in the tree. Extents with EXTENT_IO in their state field | |
250 | * are not merged because the end_io handlers need to be able to do | |
251 | * operations on them without sleeping (or doing allocations/splits). | |
252 | * | |
253 | * This should be called with the tree lock held. | |
254 | */ | |
255 | static int merge_state(struct extent_io_tree *tree, | |
256 | struct extent_state *state) | |
257 | { | |
258 | struct extent_state *other; | |
259 | struct rb_node *other_node; | |
260 | ||
5b21f2ed | 261 | if (state->state & (EXTENT_IOBITS | EXTENT_BOUNDARY)) |
d1310b2e CM |
262 | return 0; |
263 | ||
264 | other_node = rb_prev(&state->rb_node); | |
265 | if (other_node) { | |
266 | other = rb_entry(other_node, struct extent_state, rb_node); | |
267 | if (other->end == state->start - 1 && | |
268 | other->state == state->state) { | |
9ed74f2d | 269 | merge_cb(tree, state, other); |
d1310b2e | 270 | state->start = other->start; |
70dec807 | 271 | other->tree = NULL; |
d1310b2e CM |
272 | rb_erase(&other->rb_node, &tree->state); |
273 | free_extent_state(other); | |
274 | } | |
275 | } | |
276 | other_node = rb_next(&state->rb_node); | |
277 | if (other_node) { | |
278 | other = rb_entry(other_node, struct extent_state, rb_node); | |
279 | if (other->start == state->end + 1 && | |
280 | other->state == state->state) { | |
9ed74f2d | 281 | merge_cb(tree, state, other); |
d1310b2e | 282 | other->start = state->start; |
70dec807 | 283 | state->tree = NULL; |
d1310b2e CM |
284 | rb_erase(&state->rb_node, &tree->state); |
285 | free_extent_state(state); | |
9ed74f2d | 286 | state = NULL; |
d1310b2e CM |
287 | } |
288 | } | |
9ed74f2d | 289 | |
d1310b2e CM |
290 | return 0; |
291 | } | |
292 | ||
9ed74f2d | 293 | static int set_state_cb(struct extent_io_tree *tree, |
0ca1f7ce | 294 | struct extent_state *state, int *bits) |
291d673e CM |
295 | { |
296 | if (tree->ops && tree->ops->set_bit_hook) { | |
9ed74f2d | 297 | return tree->ops->set_bit_hook(tree->mapping->host, |
0ca1f7ce | 298 | state, bits); |
291d673e | 299 | } |
9ed74f2d JB |
300 | |
301 | return 0; | |
291d673e CM |
302 | } |
303 | ||
304 | static void clear_state_cb(struct extent_io_tree *tree, | |
0ca1f7ce | 305 | struct extent_state *state, int *bits) |
291d673e | 306 | { |
9ed74f2d JB |
307 | if (tree->ops && tree->ops->clear_bit_hook) |
308 | tree->ops->clear_bit_hook(tree->mapping->host, state, bits); | |
291d673e CM |
309 | } |
310 | ||
d1310b2e CM |
311 | /* |
312 | * insert an extent_state struct into the tree. 'bits' are set on the | |
313 | * struct before it is inserted. | |
314 | * | |
315 | * This may return -EEXIST if the extent is already there, in which case the | |
316 | * state struct is freed. | |
317 | * | |
318 | * The tree lock is not taken internally. This is a utility function and | |
319 | * probably isn't what you want to call (see set/clear_extent_bit). | |
320 | */ | |
321 | static int insert_state(struct extent_io_tree *tree, | |
322 | struct extent_state *state, u64 start, u64 end, | |
0ca1f7ce | 323 | int *bits) |
d1310b2e CM |
324 | { |
325 | struct rb_node *node; | |
0ca1f7ce | 326 | int bits_to_set = *bits & ~EXTENT_CTLBITS; |
9ed74f2d | 327 | int ret; |
d1310b2e CM |
328 | |
329 | if (end < start) { | |
d397712b CM |
330 | printk(KERN_ERR "btrfs end < start %llu %llu\n", |
331 | (unsigned long long)end, | |
332 | (unsigned long long)start); | |
d1310b2e CM |
333 | WARN_ON(1); |
334 | } | |
d1310b2e CM |
335 | state->start = start; |
336 | state->end = end; | |
9ed74f2d JB |
337 | ret = set_state_cb(tree, state, bits); |
338 | if (ret) | |
339 | return ret; | |
340 | ||
0ca1f7ce | 341 | if (bits_to_set & EXTENT_DIRTY) |
9ed74f2d | 342 | tree->dirty_bytes += end - start + 1; |
0ca1f7ce | 343 | state->state |= bits_to_set; |
d1310b2e CM |
344 | node = tree_insert(&tree->state, end, &state->rb_node); |
345 | if (node) { | |
346 | struct extent_state *found; | |
347 | found = rb_entry(node, struct extent_state, rb_node); | |
d397712b CM |
348 | printk(KERN_ERR "btrfs found node %llu %llu on insert of " |
349 | "%llu %llu\n", (unsigned long long)found->start, | |
350 | (unsigned long long)found->end, | |
351 | (unsigned long long)start, (unsigned long long)end); | |
d1310b2e CM |
352 | free_extent_state(state); |
353 | return -EEXIST; | |
354 | } | |
70dec807 | 355 | state->tree = tree; |
d1310b2e CM |
356 | merge_state(tree, state); |
357 | return 0; | |
358 | } | |
359 | ||
9ed74f2d JB |
360 | static int split_cb(struct extent_io_tree *tree, struct extent_state *orig, |
361 | u64 split) | |
362 | { | |
363 | if (tree->ops && tree->ops->split_extent_hook) | |
364 | return tree->ops->split_extent_hook(tree->mapping->host, | |
365 | orig, split); | |
366 | return 0; | |
367 | } | |
368 | ||
d1310b2e CM |
369 | /* |
370 | * split a given extent state struct in two, inserting the preallocated | |
371 | * struct 'prealloc' as the newly created second half. 'split' indicates an | |
372 | * offset inside 'orig' where it should be split. | |
373 | * | |
374 | * Before calling, | |
375 | * the tree has 'orig' at [orig->start, orig->end]. After calling, there | |
376 | * are two extent state structs in the tree: | |
377 | * prealloc: [orig->start, split - 1] | |
378 | * orig: [ split, orig->end ] | |
379 | * | |
380 | * The tree locks are not taken by this function. They need to be held | |
381 | * by the caller. | |
382 | */ | |
383 | static int split_state(struct extent_io_tree *tree, struct extent_state *orig, | |
384 | struct extent_state *prealloc, u64 split) | |
385 | { | |
386 | struct rb_node *node; | |
9ed74f2d JB |
387 | |
388 | split_cb(tree, orig, split); | |
389 | ||
d1310b2e CM |
390 | prealloc->start = orig->start; |
391 | prealloc->end = split - 1; | |
392 | prealloc->state = orig->state; | |
393 | orig->start = split; | |
394 | ||
395 | node = tree_insert(&tree->state, prealloc->end, &prealloc->rb_node); | |
396 | if (node) { | |
d1310b2e CM |
397 | free_extent_state(prealloc); |
398 | return -EEXIST; | |
399 | } | |
70dec807 | 400 | prealloc->tree = tree; |
d1310b2e CM |
401 | return 0; |
402 | } | |
403 | ||
404 | /* | |
405 | * utility function to clear some bits in an extent state struct. | |
406 | * it will optionally wake up any one waiting on this state (wake == 1), or | |
407 | * forcibly remove the state from the tree (delete == 1). | |
408 | * | |
409 | * If no bits are set on the state struct after clearing things, the | |
410 | * struct is freed and removed from the tree | |
411 | */ | |
412 | static int clear_state_bit(struct extent_io_tree *tree, | |
0ca1f7ce YZ |
413 | struct extent_state *state, |
414 | int *bits, int wake) | |
d1310b2e | 415 | { |
0ca1f7ce | 416 | int bits_to_clear = *bits & ~EXTENT_CTLBITS; |
32c00aff | 417 | int ret = state->state & bits_to_clear; |
d1310b2e | 418 | |
0ca1f7ce | 419 | if ((bits_to_clear & EXTENT_DIRTY) && (state->state & EXTENT_DIRTY)) { |
d1310b2e CM |
420 | u64 range = state->end - state->start + 1; |
421 | WARN_ON(range > tree->dirty_bytes); | |
422 | tree->dirty_bytes -= range; | |
423 | } | |
291d673e | 424 | clear_state_cb(tree, state, bits); |
32c00aff | 425 | state->state &= ~bits_to_clear; |
d1310b2e CM |
426 | if (wake) |
427 | wake_up(&state->wq); | |
0ca1f7ce | 428 | if (state->state == 0) { |
70dec807 | 429 | if (state->tree) { |
d1310b2e | 430 | rb_erase(&state->rb_node, &tree->state); |
70dec807 | 431 | state->tree = NULL; |
d1310b2e CM |
432 | free_extent_state(state); |
433 | } else { | |
434 | WARN_ON(1); | |
435 | } | |
436 | } else { | |
437 | merge_state(tree, state); | |
438 | } | |
439 | return ret; | |
440 | } | |
441 | ||
8233767a XG |
442 | static struct extent_state * |
443 | alloc_extent_state_atomic(struct extent_state *prealloc) | |
444 | { | |
445 | if (!prealloc) | |
446 | prealloc = alloc_extent_state(GFP_ATOMIC); | |
447 | ||
448 | return prealloc; | |
449 | } | |
450 | ||
d1310b2e CM |
451 | /* |
452 | * clear some bits on a range in the tree. This may require splitting | |
453 | * or inserting elements in the tree, so the gfp mask is used to | |
454 | * indicate which allocations or sleeping are allowed. | |
455 | * | |
456 | * pass 'wake' == 1 to kick any sleepers, and 'delete' == 1 to remove | |
457 | * the given range from the tree regardless of state (ie for truncate). | |
458 | * | |
459 | * the range [start, end] is inclusive. | |
460 | * | |
461 | * This takes the tree lock, and returns < 0 on error, > 0 if any of the | |
462 | * bits were already set, or zero if none of the bits were already set. | |
463 | */ | |
464 | int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, | |
2c64c53d CM |
465 | int bits, int wake, int delete, |
466 | struct extent_state **cached_state, | |
467 | gfp_t mask) | |
d1310b2e CM |
468 | { |
469 | struct extent_state *state; | |
2c64c53d | 470 | struct extent_state *cached; |
d1310b2e | 471 | struct extent_state *prealloc = NULL; |
2c64c53d | 472 | struct rb_node *next_node; |
d1310b2e | 473 | struct rb_node *node; |
5c939df5 | 474 | u64 last_end; |
d1310b2e CM |
475 | int err; |
476 | int set = 0; | |
2ac55d41 | 477 | int clear = 0; |
d1310b2e | 478 | |
0ca1f7ce YZ |
479 | if (delete) |
480 | bits |= ~EXTENT_CTLBITS; | |
481 | bits |= EXTENT_FIRST_DELALLOC; | |
482 | ||
2ac55d41 JB |
483 | if (bits & (EXTENT_IOBITS | EXTENT_BOUNDARY)) |
484 | clear = 1; | |
d1310b2e CM |
485 | again: |
486 | if (!prealloc && (mask & __GFP_WAIT)) { | |
487 | prealloc = alloc_extent_state(mask); | |
c309df07 CM |
488 | if (!prealloc) |
489 | return -ENOMEM; | |
d1310b2e CM |
490 | } |
491 | ||
cad321ad | 492 | spin_lock(&tree->lock); |
2c64c53d CM |
493 | if (cached_state) { |
494 | cached = *cached_state; | |
2ac55d41 JB |
495 | |
496 | if (clear) { | |
497 | *cached_state = NULL; | |
498 | cached_state = NULL; | |
499 | } | |
500 | ||
42daec29 | 501 | if (cached && cached->tree && cached->start == start) { |
2ac55d41 JB |
502 | if (clear) |
503 | atomic_dec(&cached->refs); | |
2c64c53d | 504 | state = cached; |
42daec29 | 505 | goto hit_next; |
2c64c53d | 506 | } |
2ac55d41 JB |
507 | if (clear) |
508 | free_extent_state(cached); | |
2c64c53d | 509 | } |
d1310b2e CM |
510 | /* |
511 | * this search will find the extents that end after | |
512 | * our range starts | |
513 | */ | |
80ea96b1 | 514 | node = tree_search(tree, start); |
d1310b2e CM |
515 | if (!node) |
516 | goto out; | |
517 | state = rb_entry(node, struct extent_state, rb_node); | |
2c64c53d | 518 | hit_next: |
d1310b2e CM |
519 | if (state->start > end) |
520 | goto out; | |
521 | WARN_ON(state->end < start); | |
5c939df5 | 522 | last_end = state->end; |
d1310b2e CM |
523 | |
524 | /* | |
525 | * | ---- desired range ---- | | |
526 | * | state | or | |
527 | * | ------------- state -------------- | | |
528 | * | |
529 | * We need to split the extent we found, and may flip | |
530 | * bits on second half. | |
531 | * | |
532 | * If the extent we found extends past our range, we | |
533 | * just split and search again. It'll get split again | |
534 | * the next time though. | |
535 | * | |
536 | * If the extent we found is inside our range, we clear | |
537 | * the desired bit on it. | |
538 | */ | |
539 | ||
540 | if (state->start < start) { | |
8233767a XG |
541 | prealloc = alloc_extent_state_atomic(prealloc); |
542 | BUG_ON(!prealloc); | |
d1310b2e CM |
543 | err = split_state(tree, state, prealloc, start); |
544 | BUG_ON(err == -EEXIST); | |
545 | prealloc = NULL; | |
546 | if (err) | |
547 | goto out; | |
548 | if (state->end <= end) { | |
0ca1f7ce | 549 | set |= clear_state_bit(tree, state, &bits, wake); |
5c939df5 YZ |
550 | if (last_end == (u64)-1) |
551 | goto out; | |
552 | start = last_end + 1; | |
d1310b2e CM |
553 | } |
554 | goto search_again; | |
555 | } | |
556 | /* | |
557 | * | ---- desired range ---- | | |
558 | * | state | | |
559 | * We need to split the extent, and clear the bit | |
560 | * on the first half | |
561 | */ | |
562 | if (state->start <= end && state->end > end) { | |
8233767a XG |
563 | prealloc = alloc_extent_state_atomic(prealloc); |
564 | BUG_ON(!prealloc); | |
d1310b2e CM |
565 | err = split_state(tree, state, prealloc, end + 1); |
566 | BUG_ON(err == -EEXIST); | |
d1310b2e CM |
567 | if (wake) |
568 | wake_up(&state->wq); | |
42daec29 | 569 | |
0ca1f7ce | 570 | set |= clear_state_bit(tree, prealloc, &bits, wake); |
9ed74f2d | 571 | |
d1310b2e CM |
572 | prealloc = NULL; |
573 | goto out; | |
574 | } | |
42daec29 | 575 | |
2c64c53d CM |
576 | if (state->end < end && prealloc && !need_resched()) |
577 | next_node = rb_next(&state->rb_node); | |
578 | else | |
579 | next_node = NULL; | |
42daec29 | 580 | |
0ca1f7ce | 581 | set |= clear_state_bit(tree, state, &bits, wake); |
5c939df5 YZ |
582 | if (last_end == (u64)-1) |
583 | goto out; | |
584 | start = last_end + 1; | |
2c64c53d CM |
585 | if (start <= end && next_node) { |
586 | state = rb_entry(next_node, struct extent_state, | |
587 | rb_node); | |
588 | if (state->start == start) | |
589 | goto hit_next; | |
590 | } | |
d1310b2e CM |
591 | goto search_again; |
592 | ||
593 | out: | |
cad321ad | 594 | spin_unlock(&tree->lock); |
d1310b2e CM |
595 | if (prealloc) |
596 | free_extent_state(prealloc); | |
597 | ||
598 | return set; | |
599 | ||
600 | search_again: | |
601 | if (start > end) | |
602 | goto out; | |
cad321ad | 603 | spin_unlock(&tree->lock); |
d1310b2e CM |
604 | if (mask & __GFP_WAIT) |
605 | cond_resched(); | |
606 | goto again; | |
607 | } | |
d1310b2e CM |
608 | |
609 | static int wait_on_state(struct extent_io_tree *tree, | |
610 | struct extent_state *state) | |
641f5219 CH |
611 | __releases(tree->lock) |
612 | __acquires(tree->lock) | |
d1310b2e CM |
613 | { |
614 | DEFINE_WAIT(wait); | |
615 | prepare_to_wait(&state->wq, &wait, TASK_UNINTERRUPTIBLE); | |
cad321ad | 616 | spin_unlock(&tree->lock); |
d1310b2e | 617 | schedule(); |
cad321ad | 618 | spin_lock(&tree->lock); |
d1310b2e CM |
619 | finish_wait(&state->wq, &wait); |
620 | return 0; | |
621 | } | |
622 | ||
623 | /* | |
624 | * waits for one or more bits to clear on a range in the state tree. | |
625 | * The range [start, end] is inclusive. | |
626 | * The tree lock is taken by this function | |
627 | */ | |
628 | int wait_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, int bits) | |
629 | { | |
630 | struct extent_state *state; | |
631 | struct rb_node *node; | |
632 | ||
cad321ad | 633 | spin_lock(&tree->lock); |
d1310b2e CM |
634 | again: |
635 | while (1) { | |
636 | /* | |
637 | * this search will find all the extents that end after | |
638 | * our range starts | |
639 | */ | |
80ea96b1 | 640 | node = tree_search(tree, start); |
d1310b2e CM |
641 | if (!node) |
642 | break; | |
643 | ||
644 | state = rb_entry(node, struct extent_state, rb_node); | |
645 | ||
646 | if (state->start > end) | |
647 | goto out; | |
648 | ||
649 | if (state->state & bits) { | |
650 | start = state->start; | |
651 | atomic_inc(&state->refs); | |
652 | wait_on_state(tree, state); | |
653 | free_extent_state(state); | |
654 | goto again; | |
655 | } | |
656 | start = state->end + 1; | |
657 | ||
658 | if (start > end) | |
659 | break; | |
660 | ||
661 | if (need_resched()) { | |
cad321ad | 662 | spin_unlock(&tree->lock); |
d1310b2e | 663 | cond_resched(); |
cad321ad | 664 | spin_lock(&tree->lock); |
d1310b2e CM |
665 | } |
666 | } | |
667 | out: | |
cad321ad | 668 | spin_unlock(&tree->lock); |
d1310b2e CM |
669 | return 0; |
670 | } | |
d1310b2e | 671 | |
9ed74f2d | 672 | static int set_state_bits(struct extent_io_tree *tree, |
d1310b2e | 673 | struct extent_state *state, |
0ca1f7ce | 674 | int *bits) |
d1310b2e | 675 | { |
9ed74f2d | 676 | int ret; |
0ca1f7ce | 677 | int bits_to_set = *bits & ~EXTENT_CTLBITS; |
9ed74f2d JB |
678 | |
679 | ret = set_state_cb(tree, state, bits); | |
680 | if (ret) | |
681 | return ret; | |
0ca1f7ce | 682 | if ((bits_to_set & EXTENT_DIRTY) && !(state->state & EXTENT_DIRTY)) { |
d1310b2e CM |
683 | u64 range = state->end - state->start + 1; |
684 | tree->dirty_bytes += range; | |
685 | } | |
0ca1f7ce | 686 | state->state |= bits_to_set; |
9ed74f2d JB |
687 | |
688 | return 0; | |
d1310b2e CM |
689 | } |
690 | ||
2c64c53d CM |
691 | static void cache_state(struct extent_state *state, |
692 | struct extent_state **cached_ptr) | |
693 | { | |
694 | if (cached_ptr && !(*cached_ptr)) { | |
695 | if (state->state & (EXTENT_IOBITS | EXTENT_BOUNDARY)) { | |
696 | *cached_ptr = state; | |
697 | atomic_inc(&state->refs); | |
698 | } | |
699 | } | |
700 | } | |
701 | ||
507903b8 AJ |
702 | static void uncache_state(struct extent_state **cached_ptr) |
703 | { | |
704 | if (cached_ptr && (*cached_ptr)) { | |
705 | struct extent_state *state = *cached_ptr; | |
109b36a2 CM |
706 | *cached_ptr = NULL; |
707 | free_extent_state(state); | |
507903b8 AJ |
708 | } |
709 | } | |
710 | ||
d1310b2e | 711 | /* |
1edbb734 CM |
712 | * set some bits on a range in the tree. This may require allocations or |
713 | * sleeping, so the gfp mask is used to indicate what is allowed. | |
d1310b2e | 714 | * |
1edbb734 CM |
715 | * If any of the exclusive bits are set, this will fail with -EEXIST if some |
716 | * part of the range already has the desired bits set. The start of the | |
717 | * existing range is returned in failed_start in this case. | |
d1310b2e | 718 | * |
1edbb734 | 719 | * [start, end] is inclusive This takes the tree lock. |
d1310b2e | 720 | */ |
1edbb734 | 721 | |
4845e44f CM |
722 | int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, |
723 | int bits, int exclusive_bits, u64 *failed_start, | |
724 | struct extent_state **cached_state, gfp_t mask) | |
d1310b2e CM |
725 | { |
726 | struct extent_state *state; | |
727 | struct extent_state *prealloc = NULL; | |
728 | struct rb_node *node; | |
d1310b2e | 729 | int err = 0; |
d1310b2e CM |
730 | u64 last_start; |
731 | u64 last_end; | |
42daec29 | 732 | |
0ca1f7ce | 733 | bits |= EXTENT_FIRST_DELALLOC; |
d1310b2e CM |
734 | again: |
735 | if (!prealloc && (mask & __GFP_WAIT)) { | |
736 | prealloc = alloc_extent_state(mask); | |
8233767a | 737 | BUG_ON(!prealloc); |
d1310b2e CM |
738 | } |
739 | ||
cad321ad | 740 | spin_lock(&tree->lock); |
9655d298 CM |
741 | if (cached_state && *cached_state) { |
742 | state = *cached_state; | |
743 | if (state->start == start && state->tree) { | |
744 | node = &state->rb_node; | |
745 | goto hit_next; | |
746 | } | |
747 | } | |
d1310b2e CM |
748 | /* |
749 | * this search will find all the extents that end after | |
750 | * our range starts. | |
751 | */ | |
80ea96b1 | 752 | node = tree_search(tree, start); |
d1310b2e | 753 | if (!node) { |
8233767a XG |
754 | prealloc = alloc_extent_state_atomic(prealloc); |
755 | BUG_ON(!prealloc); | |
0ca1f7ce | 756 | err = insert_state(tree, prealloc, start, end, &bits); |
d1310b2e CM |
757 | prealloc = NULL; |
758 | BUG_ON(err == -EEXIST); | |
759 | goto out; | |
760 | } | |
d1310b2e | 761 | state = rb_entry(node, struct extent_state, rb_node); |
40431d6c | 762 | hit_next: |
d1310b2e CM |
763 | last_start = state->start; |
764 | last_end = state->end; | |
765 | ||
766 | /* | |
767 | * | ---- desired range ---- | | |
768 | * | state | | |
769 | * | |
770 | * Just lock what we found and keep going | |
771 | */ | |
772 | if (state->start == start && state->end <= end) { | |
40431d6c | 773 | struct rb_node *next_node; |
1edbb734 | 774 | if (state->state & exclusive_bits) { |
d1310b2e CM |
775 | *failed_start = state->start; |
776 | err = -EEXIST; | |
777 | goto out; | |
778 | } | |
42daec29 | 779 | |
0ca1f7ce | 780 | err = set_state_bits(tree, state, &bits); |
9ed74f2d JB |
781 | if (err) |
782 | goto out; | |
783 | ||
c7f895a2 | 784 | next_node = rb_next(node); |
2c64c53d | 785 | cache_state(state, cached_state); |
d1310b2e | 786 | merge_state(tree, state); |
5c939df5 YZ |
787 | if (last_end == (u64)-1) |
788 | goto out; | |
40431d6c | 789 | |
5c939df5 | 790 | start = last_end + 1; |
c7f895a2 XG |
791 | if (next_node && start < end && prealloc && !need_resched()) { |
792 | state = rb_entry(next_node, struct extent_state, | |
793 | rb_node); | |
794 | if (state->start == start) | |
795 | goto hit_next; | |
40431d6c | 796 | } |
d1310b2e CM |
797 | goto search_again; |
798 | } | |
799 | ||
800 | /* | |
801 | * | ---- desired range ---- | | |
802 | * | state | | |
803 | * or | |
804 | * | ------------- state -------------- | | |
805 | * | |
806 | * We need to split the extent we found, and may flip bits on | |
807 | * second half. | |
808 | * | |
809 | * If the extent we found extends past our | |
810 | * range, we just split and search again. It'll get split | |
811 | * again the next time though. | |
812 | * | |
813 | * If the extent we found is inside our range, we set the | |
814 | * desired bit on it. | |
815 | */ | |
816 | if (state->start < start) { | |
1edbb734 | 817 | if (state->state & exclusive_bits) { |
d1310b2e CM |
818 | *failed_start = start; |
819 | err = -EEXIST; | |
820 | goto out; | |
821 | } | |
8233767a XG |
822 | |
823 | prealloc = alloc_extent_state_atomic(prealloc); | |
824 | BUG_ON(!prealloc); | |
d1310b2e CM |
825 | err = split_state(tree, state, prealloc, start); |
826 | BUG_ON(err == -EEXIST); | |
827 | prealloc = NULL; | |
828 | if (err) | |
829 | goto out; | |
830 | if (state->end <= end) { | |
0ca1f7ce | 831 | err = set_state_bits(tree, state, &bits); |
9ed74f2d JB |
832 | if (err) |
833 | goto out; | |
2c64c53d | 834 | cache_state(state, cached_state); |
d1310b2e | 835 | merge_state(tree, state); |
5c939df5 YZ |
836 | if (last_end == (u64)-1) |
837 | goto out; | |
838 | start = last_end + 1; | |
d1310b2e CM |
839 | } |
840 | goto search_again; | |
841 | } | |
842 | /* | |
843 | * | ---- desired range ---- | | |
844 | * | state | or | state | | |
845 | * | |
846 | * There's a hole, we need to insert something in it and | |
847 | * ignore the extent we found. | |
848 | */ | |
849 | if (state->start > start) { | |
850 | u64 this_end; | |
851 | if (end < last_start) | |
852 | this_end = end; | |
853 | else | |
d397712b | 854 | this_end = last_start - 1; |
8233767a XG |
855 | |
856 | prealloc = alloc_extent_state_atomic(prealloc); | |
857 | BUG_ON(!prealloc); | |
c7f895a2 XG |
858 | |
859 | /* | |
860 | * Avoid to free 'prealloc' if it can be merged with | |
861 | * the later extent. | |
862 | */ | |
863 | atomic_inc(&prealloc->refs); | |
d1310b2e | 864 | err = insert_state(tree, prealloc, start, this_end, |
0ca1f7ce | 865 | &bits); |
d1310b2e | 866 | BUG_ON(err == -EEXIST); |
9ed74f2d | 867 | if (err) { |
c7f895a2 | 868 | free_extent_state(prealloc); |
9ed74f2d | 869 | prealloc = NULL; |
d1310b2e | 870 | goto out; |
9ed74f2d JB |
871 | } |
872 | cache_state(prealloc, cached_state); | |
c7f895a2 | 873 | free_extent_state(prealloc); |
9ed74f2d | 874 | prealloc = NULL; |
d1310b2e CM |
875 | start = this_end + 1; |
876 | goto search_again; | |
877 | } | |
878 | /* | |
879 | * | ---- desired range ---- | | |
880 | * | state | | |
881 | * We need to split the extent, and set the bit | |
882 | * on the first half | |
883 | */ | |
884 | if (state->start <= end && state->end > end) { | |
1edbb734 | 885 | if (state->state & exclusive_bits) { |
d1310b2e CM |
886 | *failed_start = start; |
887 | err = -EEXIST; | |
888 | goto out; | |
889 | } | |
8233767a XG |
890 | |
891 | prealloc = alloc_extent_state_atomic(prealloc); | |
892 | BUG_ON(!prealloc); | |
d1310b2e CM |
893 | err = split_state(tree, state, prealloc, end + 1); |
894 | BUG_ON(err == -EEXIST); | |
895 | ||
0ca1f7ce | 896 | err = set_state_bits(tree, prealloc, &bits); |
9ed74f2d JB |
897 | if (err) { |
898 | prealloc = NULL; | |
899 | goto out; | |
900 | } | |
2c64c53d | 901 | cache_state(prealloc, cached_state); |
d1310b2e CM |
902 | merge_state(tree, prealloc); |
903 | prealloc = NULL; | |
904 | goto out; | |
905 | } | |
906 | ||
907 | goto search_again; | |
908 | ||
909 | out: | |
cad321ad | 910 | spin_unlock(&tree->lock); |
d1310b2e CM |
911 | if (prealloc) |
912 | free_extent_state(prealloc); | |
913 | ||
914 | return err; | |
915 | ||
916 | search_again: | |
917 | if (start > end) | |
918 | goto out; | |
cad321ad | 919 | spin_unlock(&tree->lock); |
d1310b2e CM |
920 | if (mask & __GFP_WAIT) |
921 | cond_resched(); | |
922 | goto again; | |
923 | } | |
d1310b2e CM |
924 | |
925 | /* wrappers around set/clear extent bit */ | |
926 | int set_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end, | |
927 | gfp_t mask) | |
928 | { | |
929 | return set_extent_bit(tree, start, end, EXTENT_DIRTY, 0, NULL, | |
2c64c53d | 930 | NULL, mask); |
d1310b2e | 931 | } |
d1310b2e CM |
932 | |
933 | int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, | |
934 | int bits, gfp_t mask) | |
935 | { | |
936 | return set_extent_bit(tree, start, end, bits, 0, NULL, | |
2c64c53d | 937 | NULL, mask); |
d1310b2e | 938 | } |
d1310b2e CM |
939 | |
940 | int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, | |
941 | int bits, gfp_t mask) | |
942 | { | |
2c64c53d | 943 | return clear_extent_bit(tree, start, end, bits, 0, 0, NULL, mask); |
d1310b2e | 944 | } |
d1310b2e CM |
945 | |
946 | int set_extent_delalloc(struct extent_io_tree *tree, u64 start, u64 end, | |
2ac55d41 | 947 | struct extent_state **cached_state, gfp_t mask) |
d1310b2e CM |
948 | { |
949 | return set_extent_bit(tree, start, end, | |
40431d6c | 950 | EXTENT_DELALLOC | EXTENT_DIRTY | EXTENT_UPTODATE, |
2ac55d41 | 951 | 0, NULL, cached_state, mask); |
d1310b2e | 952 | } |
d1310b2e CM |
953 | |
954 | int clear_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end, | |
955 | gfp_t mask) | |
956 | { | |
957 | return clear_extent_bit(tree, start, end, | |
32c00aff | 958 | EXTENT_DIRTY | EXTENT_DELALLOC | |
0ca1f7ce | 959 | EXTENT_DO_ACCOUNTING, 0, 0, NULL, mask); |
d1310b2e | 960 | } |
d1310b2e CM |
961 | |
962 | int set_extent_new(struct extent_io_tree *tree, u64 start, u64 end, | |
963 | gfp_t mask) | |
964 | { | |
965 | return set_extent_bit(tree, start, end, EXTENT_NEW, 0, NULL, | |
2c64c53d | 966 | NULL, mask); |
d1310b2e | 967 | } |
d1310b2e | 968 | |
d1310b2e | 969 | int set_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end, |
507903b8 | 970 | struct extent_state **cached_state, gfp_t mask) |
d1310b2e | 971 | { |
507903b8 AJ |
972 | return set_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, |
973 | NULL, cached_state, mask); | |
d1310b2e | 974 | } |
d1310b2e | 975 | |
d397712b | 976 | static int clear_extent_uptodate(struct extent_io_tree *tree, u64 start, |
2ac55d41 JB |
977 | u64 end, struct extent_state **cached_state, |
978 | gfp_t mask) | |
d1310b2e | 979 | { |
2c64c53d | 980 | return clear_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, 0, |
2ac55d41 | 981 | cached_state, mask); |
d1310b2e | 982 | } |
d1310b2e | 983 | |
d352ac68 CM |
984 | /* |
985 | * either insert or lock state struct between start and end use mask to tell | |
986 | * us if waiting is desired. | |
987 | */ | |
1edbb734 | 988 | int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, |
2c64c53d | 989 | int bits, struct extent_state **cached_state, gfp_t mask) |
d1310b2e CM |
990 | { |
991 | int err; | |
992 | u64 failed_start; | |
993 | while (1) { | |
1edbb734 | 994 | err = set_extent_bit(tree, start, end, EXTENT_LOCKED | bits, |
2c64c53d CM |
995 | EXTENT_LOCKED, &failed_start, |
996 | cached_state, mask); | |
d1310b2e CM |
997 | if (err == -EEXIST && (mask & __GFP_WAIT)) { |
998 | wait_extent_bit(tree, failed_start, end, EXTENT_LOCKED); | |
999 | start = failed_start; | |
1000 | } else { | |
1001 | break; | |
1002 | } | |
1003 | WARN_ON(start > end); | |
1004 | } | |
1005 | return err; | |
1006 | } | |
d1310b2e | 1007 | |
1edbb734 CM |
1008 | int lock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask) |
1009 | { | |
2c64c53d | 1010 | return lock_extent_bits(tree, start, end, 0, NULL, mask); |
1edbb734 CM |
1011 | } |
1012 | ||
25179201 JB |
1013 | int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end, |
1014 | gfp_t mask) | |
1015 | { | |
1016 | int err; | |
1017 | u64 failed_start; | |
1018 | ||
2c64c53d CM |
1019 | err = set_extent_bit(tree, start, end, EXTENT_LOCKED, EXTENT_LOCKED, |
1020 | &failed_start, NULL, mask); | |
6643558d YZ |
1021 | if (err == -EEXIST) { |
1022 | if (failed_start > start) | |
1023 | clear_extent_bit(tree, start, failed_start - 1, | |
2c64c53d | 1024 | EXTENT_LOCKED, 1, 0, NULL, mask); |
25179201 | 1025 | return 0; |
6643558d | 1026 | } |
25179201 JB |
1027 | return 1; |
1028 | } | |
25179201 | 1029 | |
2c64c53d CM |
1030 | int unlock_extent_cached(struct extent_io_tree *tree, u64 start, u64 end, |
1031 | struct extent_state **cached, gfp_t mask) | |
1032 | { | |
1033 | return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, cached, | |
1034 | mask); | |
1035 | } | |
1036 | ||
507903b8 | 1037 | int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask) |
d1310b2e | 1038 | { |
2c64c53d CM |
1039 | return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, NULL, |
1040 | mask); | |
d1310b2e | 1041 | } |
d1310b2e | 1042 | |
d1310b2e CM |
1043 | /* |
1044 | * helper function to set both pages and extents in the tree writeback | |
1045 | */ | |
b2950863 | 1046 | static int set_range_writeback(struct extent_io_tree *tree, u64 start, u64 end) |
d1310b2e CM |
1047 | { |
1048 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1049 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
1050 | struct page *page; | |
1051 | ||
1052 | while (index <= end_index) { | |
1053 | page = find_get_page(tree->mapping, index); | |
1054 | BUG_ON(!page); | |
1055 | set_page_writeback(page); | |
1056 | page_cache_release(page); | |
1057 | index++; | |
1058 | } | |
d1310b2e CM |
1059 | return 0; |
1060 | } | |
d1310b2e | 1061 | |
d352ac68 CM |
1062 | /* |
1063 | * find the first offset in the io tree with 'bits' set. zero is | |
1064 | * returned if we find something, and *start_ret and *end_ret are | |
1065 | * set to reflect the state struct that was found. | |
1066 | * | |
1067 | * If nothing was found, 1 is returned, < 0 on error | |
1068 | */ | |
d1310b2e CM |
1069 | int find_first_extent_bit(struct extent_io_tree *tree, u64 start, |
1070 | u64 *start_ret, u64 *end_ret, int bits) | |
1071 | { | |
1072 | struct rb_node *node; | |
1073 | struct extent_state *state; | |
1074 | int ret = 1; | |
1075 | ||
cad321ad | 1076 | spin_lock(&tree->lock); |
d1310b2e CM |
1077 | /* |
1078 | * this search will find all the extents that end after | |
1079 | * our range starts. | |
1080 | */ | |
80ea96b1 | 1081 | node = tree_search(tree, start); |
d397712b | 1082 | if (!node) |
d1310b2e | 1083 | goto out; |
d1310b2e | 1084 | |
d397712b | 1085 | while (1) { |
d1310b2e CM |
1086 | state = rb_entry(node, struct extent_state, rb_node); |
1087 | if (state->end >= start && (state->state & bits)) { | |
1088 | *start_ret = state->start; | |
1089 | *end_ret = state->end; | |
1090 | ret = 0; | |
1091 | break; | |
1092 | } | |
1093 | node = rb_next(node); | |
1094 | if (!node) | |
1095 | break; | |
1096 | } | |
1097 | out: | |
cad321ad | 1098 | spin_unlock(&tree->lock); |
d1310b2e CM |
1099 | return ret; |
1100 | } | |
d1310b2e | 1101 | |
d352ac68 CM |
1102 | /* find the first state struct with 'bits' set after 'start', and |
1103 | * return it. tree->lock must be held. NULL will returned if | |
1104 | * nothing was found after 'start' | |
1105 | */ | |
d7fc640e CM |
1106 | struct extent_state *find_first_extent_bit_state(struct extent_io_tree *tree, |
1107 | u64 start, int bits) | |
1108 | { | |
1109 | struct rb_node *node; | |
1110 | struct extent_state *state; | |
1111 | ||
1112 | /* | |
1113 | * this search will find all the extents that end after | |
1114 | * our range starts. | |
1115 | */ | |
1116 | node = tree_search(tree, start); | |
d397712b | 1117 | if (!node) |
d7fc640e | 1118 | goto out; |
d7fc640e | 1119 | |
d397712b | 1120 | while (1) { |
d7fc640e | 1121 | state = rb_entry(node, struct extent_state, rb_node); |
d397712b | 1122 | if (state->end >= start && (state->state & bits)) |
d7fc640e | 1123 | return state; |
d397712b | 1124 | |
d7fc640e CM |
1125 | node = rb_next(node); |
1126 | if (!node) | |
1127 | break; | |
1128 | } | |
1129 | out: | |
1130 | return NULL; | |
1131 | } | |
d7fc640e | 1132 | |
d352ac68 CM |
1133 | /* |
1134 | * find a contiguous range of bytes in the file marked as delalloc, not | |
1135 | * more than 'max_bytes'. start and end are used to return the range, | |
1136 | * | |
1137 | * 1 is returned if we find something, 0 if nothing was in the tree | |
1138 | */ | |
c8b97818 | 1139 | static noinline u64 find_delalloc_range(struct extent_io_tree *tree, |
c2a128d2 JB |
1140 | u64 *start, u64 *end, u64 max_bytes, |
1141 | struct extent_state **cached_state) | |
d1310b2e CM |
1142 | { |
1143 | struct rb_node *node; | |
1144 | struct extent_state *state; | |
1145 | u64 cur_start = *start; | |
1146 | u64 found = 0; | |
1147 | u64 total_bytes = 0; | |
1148 | ||
cad321ad | 1149 | spin_lock(&tree->lock); |
c8b97818 | 1150 | |
d1310b2e CM |
1151 | /* |
1152 | * this search will find all the extents that end after | |
1153 | * our range starts. | |
1154 | */ | |
80ea96b1 | 1155 | node = tree_search(tree, cur_start); |
2b114d1d | 1156 | if (!node) { |
3b951516 CM |
1157 | if (!found) |
1158 | *end = (u64)-1; | |
d1310b2e CM |
1159 | goto out; |
1160 | } | |
1161 | ||
d397712b | 1162 | while (1) { |
d1310b2e | 1163 | state = rb_entry(node, struct extent_state, rb_node); |
5b21f2ed ZY |
1164 | if (found && (state->start != cur_start || |
1165 | (state->state & EXTENT_BOUNDARY))) { | |
d1310b2e CM |
1166 | goto out; |
1167 | } | |
1168 | if (!(state->state & EXTENT_DELALLOC)) { | |
1169 | if (!found) | |
1170 | *end = state->end; | |
1171 | goto out; | |
1172 | } | |
c2a128d2 | 1173 | if (!found) { |
d1310b2e | 1174 | *start = state->start; |
c2a128d2 JB |
1175 | *cached_state = state; |
1176 | atomic_inc(&state->refs); | |
1177 | } | |
d1310b2e CM |
1178 | found++; |
1179 | *end = state->end; | |
1180 | cur_start = state->end + 1; | |
1181 | node = rb_next(node); | |
1182 | if (!node) | |
1183 | break; | |
1184 | total_bytes += state->end - state->start + 1; | |
1185 | if (total_bytes >= max_bytes) | |
1186 | break; | |
1187 | } | |
1188 | out: | |
cad321ad | 1189 | spin_unlock(&tree->lock); |
d1310b2e CM |
1190 | return found; |
1191 | } | |
1192 | ||
c8b97818 CM |
1193 | static noinline int __unlock_for_delalloc(struct inode *inode, |
1194 | struct page *locked_page, | |
1195 | u64 start, u64 end) | |
1196 | { | |
1197 | int ret; | |
1198 | struct page *pages[16]; | |
1199 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1200 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
1201 | unsigned long nr_pages = end_index - index + 1; | |
1202 | int i; | |
1203 | ||
1204 | if (index == locked_page->index && end_index == index) | |
1205 | return 0; | |
1206 | ||
d397712b | 1207 | while (nr_pages > 0) { |
c8b97818 | 1208 | ret = find_get_pages_contig(inode->i_mapping, index, |
5b050f04 CM |
1209 | min_t(unsigned long, nr_pages, |
1210 | ARRAY_SIZE(pages)), pages); | |
c8b97818 CM |
1211 | for (i = 0; i < ret; i++) { |
1212 | if (pages[i] != locked_page) | |
1213 | unlock_page(pages[i]); | |
1214 | page_cache_release(pages[i]); | |
1215 | } | |
1216 | nr_pages -= ret; | |
1217 | index += ret; | |
1218 | cond_resched(); | |
1219 | } | |
1220 | return 0; | |
1221 | } | |
1222 | ||
1223 | static noinline int lock_delalloc_pages(struct inode *inode, | |
1224 | struct page *locked_page, | |
1225 | u64 delalloc_start, | |
1226 | u64 delalloc_end) | |
1227 | { | |
1228 | unsigned long index = delalloc_start >> PAGE_CACHE_SHIFT; | |
1229 | unsigned long start_index = index; | |
1230 | unsigned long end_index = delalloc_end >> PAGE_CACHE_SHIFT; | |
1231 | unsigned long pages_locked = 0; | |
1232 | struct page *pages[16]; | |
1233 | unsigned long nrpages; | |
1234 | int ret; | |
1235 | int i; | |
1236 | ||
1237 | /* the caller is responsible for locking the start index */ | |
1238 | if (index == locked_page->index && index == end_index) | |
1239 | return 0; | |
1240 | ||
1241 | /* skip the page at the start index */ | |
1242 | nrpages = end_index - index + 1; | |
d397712b | 1243 | while (nrpages > 0) { |
c8b97818 | 1244 | ret = find_get_pages_contig(inode->i_mapping, index, |
5b050f04 CM |
1245 | min_t(unsigned long, |
1246 | nrpages, ARRAY_SIZE(pages)), pages); | |
c8b97818 CM |
1247 | if (ret == 0) { |
1248 | ret = -EAGAIN; | |
1249 | goto done; | |
1250 | } | |
1251 | /* now we have an array of pages, lock them all */ | |
1252 | for (i = 0; i < ret; i++) { | |
1253 | /* | |
1254 | * the caller is taking responsibility for | |
1255 | * locked_page | |
1256 | */ | |
771ed689 | 1257 | if (pages[i] != locked_page) { |
c8b97818 | 1258 | lock_page(pages[i]); |
f2b1c41c CM |
1259 | if (!PageDirty(pages[i]) || |
1260 | pages[i]->mapping != inode->i_mapping) { | |
771ed689 CM |
1261 | ret = -EAGAIN; |
1262 | unlock_page(pages[i]); | |
1263 | page_cache_release(pages[i]); | |
1264 | goto done; | |
1265 | } | |
1266 | } | |
c8b97818 | 1267 | page_cache_release(pages[i]); |
771ed689 | 1268 | pages_locked++; |
c8b97818 | 1269 | } |
c8b97818 CM |
1270 | nrpages -= ret; |
1271 | index += ret; | |
1272 | cond_resched(); | |
1273 | } | |
1274 | ret = 0; | |
1275 | done: | |
1276 | if (ret && pages_locked) { | |
1277 | __unlock_for_delalloc(inode, locked_page, | |
1278 | delalloc_start, | |
1279 | ((u64)(start_index + pages_locked - 1)) << | |
1280 | PAGE_CACHE_SHIFT); | |
1281 | } | |
1282 | return ret; | |
1283 | } | |
1284 | ||
1285 | /* | |
1286 | * find a contiguous range of bytes in the file marked as delalloc, not | |
1287 | * more than 'max_bytes'. start and end are used to return the range, | |
1288 | * | |
1289 | * 1 is returned if we find something, 0 if nothing was in the tree | |
1290 | */ | |
1291 | static noinline u64 find_lock_delalloc_range(struct inode *inode, | |
1292 | struct extent_io_tree *tree, | |
1293 | struct page *locked_page, | |
1294 | u64 *start, u64 *end, | |
1295 | u64 max_bytes) | |
1296 | { | |
1297 | u64 delalloc_start; | |
1298 | u64 delalloc_end; | |
1299 | u64 found; | |
9655d298 | 1300 | struct extent_state *cached_state = NULL; |
c8b97818 CM |
1301 | int ret; |
1302 | int loops = 0; | |
1303 | ||
1304 | again: | |
1305 | /* step one, find a bunch of delalloc bytes starting at start */ | |
1306 | delalloc_start = *start; | |
1307 | delalloc_end = 0; | |
1308 | found = find_delalloc_range(tree, &delalloc_start, &delalloc_end, | |
c2a128d2 | 1309 | max_bytes, &cached_state); |
70b99e69 | 1310 | if (!found || delalloc_end <= *start) { |
c8b97818 CM |
1311 | *start = delalloc_start; |
1312 | *end = delalloc_end; | |
c2a128d2 | 1313 | free_extent_state(cached_state); |
c8b97818 CM |
1314 | return found; |
1315 | } | |
1316 | ||
70b99e69 CM |
1317 | /* |
1318 | * start comes from the offset of locked_page. We have to lock | |
1319 | * pages in order, so we can't process delalloc bytes before | |
1320 | * locked_page | |
1321 | */ | |
d397712b | 1322 | if (delalloc_start < *start) |
70b99e69 | 1323 | delalloc_start = *start; |
70b99e69 | 1324 | |
c8b97818 CM |
1325 | /* |
1326 | * make sure to limit the number of pages we try to lock down | |
1327 | * if we're looping. | |
1328 | */ | |
d397712b | 1329 | if (delalloc_end + 1 - delalloc_start > max_bytes && loops) |
771ed689 | 1330 | delalloc_end = delalloc_start + PAGE_CACHE_SIZE - 1; |
d397712b | 1331 | |
c8b97818 CM |
1332 | /* step two, lock all the pages after the page that has start */ |
1333 | ret = lock_delalloc_pages(inode, locked_page, | |
1334 | delalloc_start, delalloc_end); | |
1335 | if (ret == -EAGAIN) { | |
1336 | /* some of the pages are gone, lets avoid looping by | |
1337 | * shortening the size of the delalloc range we're searching | |
1338 | */ | |
9655d298 | 1339 | free_extent_state(cached_state); |
c8b97818 CM |
1340 | if (!loops) { |
1341 | unsigned long offset = (*start) & (PAGE_CACHE_SIZE - 1); | |
1342 | max_bytes = PAGE_CACHE_SIZE - offset; | |
1343 | loops = 1; | |
1344 | goto again; | |
1345 | } else { | |
1346 | found = 0; | |
1347 | goto out_failed; | |
1348 | } | |
1349 | } | |
1350 | BUG_ON(ret); | |
1351 | ||
1352 | /* step three, lock the state bits for the whole range */ | |
9655d298 CM |
1353 | lock_extent_bits(tree, delalloc_start, delalloc_end, |
1354 | 0, &cached_state, GFP_NOFS); | |
c8b97818 CM |
1355 | |
1356 | /* then test to make sure it is all still delalloc */ | |
1357 | ret = test_range_bit(tree, delalloc_start, delalloc_end, | |
9655d298 | 1358 | EXTENT_DELALLOC, 1, cached_state); |
c8b97818 | 1359 | if (!ret) { |
9655d298 CM |
1360 | unlock_extent_cached(tree, delalloc_start, delalloc_end, |
1361 | &cached_state, GFP_NOFS); | |
c8b97818 CM |
1362 | __unlock_for_delalloc(inode, locked_page, |
1363 | delalloc_start, delalloc_end); | |
1364 | cond_resched(); | |
1365 | goto again; | |
1366 | } | |
9655d298 | 1367 | free_extent_state(cached_state); |
c8b97818 CM |
1368 | *start = delalloc_start; |
1369 | *end = delalloc_end; | |
1370 | out_failed: | |
1371 | return found; | |
1372 | } | |
1373 | ||
1374 | int extent_clear_unlock_delalloc(struct inode *inode, | |
1375 | struct extent_io_tree *tree, | |
1376 | u64 start, u64 end, struct page *locked_page, | |
a791e35e | 1377 | unsigned long op) |
c8b97818 CM |
1378 | { |
1379 | int ret; | |
1380 | struct page *pages[16]; | |
1381 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
1382 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | |
1383 | unsigned long nr_pages = end_index - index + 1; | |
1384 | int i; | |
771ed689 | 1385 | int clear_bits = 0; |
c8b97818 | 1386 | |
a791e35e | 1387 | if (op & EXTENT_CLEAR_UNLOCK) |
771ed689 | 1388 | clear_bits |= EXTENT_LOCKED; |
a791e35e | 1389 | if (op & EXTENT_CLEAR_DIRTY) |
c8b97818 CM |
1390 | clear_bits |= EXTENT_DIRTY; |
1391 | ||
a791e35e | 1392 | if (op & EXTENT_CLEAR_DELALLOC) |
771ed689 CM |
1393 | clear_bits |= EXTENT_DELALLOC; |
1394 | ||
2c64c53d | 1395 | clear_extent_bit(tree, start, end, clear_bits, 1, 0, NULL, GFP_NOFS); |
32c00aff JB |
1396 | if (!(op & (EXTENT_CLEAR_UNLOCK_PAGE | EXTENT_CLEAR_DIRTY | |
1397 | EXTENT_SET_WRITEBACK | EXTENT_END_WRITEBACK | | |
1398 | EXTENT_SET_PRIVATE2))) | |
771ed689 | 1399 | return 0; |
c8b97818 | 1400 | |
d397712b | 1401 | while (nr_pages > 0) { |
c8b97818 | 1402 | ret = find_get_pages_contig(inode->i_mapping, index, |
5b050f04 CM |
1403 | min_t(unsigned long, |
1404 | nr_pages, ARRAY_SIZE(pages)), pages); | |
c8b97818 | 1405 | for (i = 0; i < ret; i++) { |
8b62b72b | 1406 | |
a791e35e | 1407 | if (op & EXTENT_SET_PRIVATE2) |
8b62b72b CM |
1408 | SetPagePrivate2(pages[i]); |
1409 | ||
c8b97818 CM |
1410 | if (pages[i] == locked_page) { |
1411 | page_cache_release(pages[i]); | |
1412 | continue; | |
1413 | } | |
a791e35e | 1414 | if (op & EXTENT_CLEAR_DIRTY) |
c8b97818 | 1415 | clear_page_dirty_for_io(pages[i]); |
a791e35e | 1416 | if (op & EXTENT_SET_WRITEBACK) |
c8b97818 | 1417 | set_page_writeback(pages[i]); |
a791e35e | 1418 | if (op & EXTENT_END_WRITEBACK) |
c8b97818 | 1419 | end_page_writeback(pages[i]); |
a791e35e | 1420 | if (op & EXTENT_CLEAR_UNLOCK_PAGE) |
771ed689 | 1421 | unlock_page(pages[i]); |
c8b97818 CM |
1422 | page_cache_release(pages[i]); |
1423 | } | |
1424 | nr_pages -= ret; | |
1425 | index += ret; | |
1426 | cond_resched(); | |
1427 | } | |
1428 | return 0; | |
1429 | } | |
c8b97818 | 1430 | |
d352ac68 CM |
1431 | /* |
1432 | * count the number of bytes in the tree that have a given bit(s) | |
1433 | * set. This can be fairly slow, except for EXTENT_DIRTY which is | |
1434 | * cached. The total number found is returned. | |
1435 | */ | |
d1310b2e CM |
1436 | u64 count_range_bits(struct extent_io_tree *tree, |
1437 | u64 *start, u64 search_end, u64 max_bytes, | |
ec29ed5b | 1438 | unsigned long bits, int contig) |
d1310b2e CM |
1439 | { |
1440 | struct rb_node *node; | |
1441 | struct extent_state *state; | |
1442 | u64 cur_start = *start; | |
1443 | u64 total_bytes = 0; | |
ec29ed5b | 1444 | u64 last = 0; |
d1310b2e CM |
1445 | int found = 0; |
1446 | ||
1447 | if (search_end <= cur_start) { | |
d1310b2e CM |
1448 | WARN_ON(1); |
1449 | return 0; | |
1450 | } | |
1451 | ||
cad321ad | 1452 | spin_lock(&tree->lock); |
d1310b2e CM |
1453 | if (cur_start == 0 && bits == EXTENT_DIRTY) { |
1454 | total_bytes = tree->dirty_bytes; | |
1455 | goto out; | |
1456 | } | |
1457 | /* | |
1458 | * this search will find all the extents that end after | |
1459 | * our range starts. | |
1460 | */ | |
80ea96b1 | 1461 | node = tree_search(tree, cur_start); |
d397712b | 1462 | if (!node) |
d1310b2e | 1463 | goto out; |
d1310b2e | 1464 | |
d397712b | 1465 | while (1) { |
d1310b2e CM |
1466 | state = rb_entry(node, struct extent_state, rb_node); |
1467 | if (state->start > search_end) | |
1468 | break; | |
ec29ed5b CM |
1469 | if (contig && found && state->start > last + 1) |
1470 | break; | |
1471 | if (state->end >= cur_start && (state->state & bits) == bits) { | |
d1310b2e CM |
1472 | total_bytes += min(search_end, state->end) + 1 - |
1473 | max(cur_start, state->start); | |
1474 | if (total_bytes >= max_bytes) | |
1475 | break; | |
1476 | if (!found) { | |
af60bed2 | 1477 | *start = max(cur_start, state->start); |
d1310b2e CM |
1478 | found = 1; |
1479 | } | |
ec29ed5b CM |
1480 | last = state->end; |
1481 | } else if (contig && found) { | |
1482 | break; | |
d1310b2e CM |
1483 | } |
1484 | node = rb_next(node); | |
1485 | if (!node) | |
1486 | break; | |
1487 | } | |
1488 | out: | |
cad321ad | 1489 | spin_unlock(&tree->lock); |
d1310b2e CM |
1490 | return total_bytes; |
1491 | } | |
b2950863 | 1492 | |
d352ac68 CM |
1493 | /* |
1494 | * set the private field for a given byte offset in the tree. If there isn't | |
1495 | * an extent_state there already, this does nothing. | |
1496 | */ | |
d1310b2e CM |
1497 | int set_state_private(struct extent_io_tree *tree, u64 start, u64 private) |
1498 | { | |
1499 | struct rb_node *node; | |
1500 | struct extent_state *state; | |
1501 | int ret = 0; | |
1502 | ||
cad321ad | 1503 | spin_lock(&tree->lock); |
d1310b2e CM |
1504 | /* |
1505 | * this search will find all the extents that end after | |
1506 | * our range starts. | |
1507 | */ | |
80ea96b1 | 1508 | node = tree_search(tree, start); |
2b114d1d | 1509 | if (!node) { |
d1310b2e CM |
1510 | ret = -ENOENT; |
1511 | goto out; | |
1512 | } | |
1513 | state = rb_entry(node, struct extent_state, rb_node); | |
1514 | if (state->start != start) { | |
1515 | ret = -ENOENT; | |
1516 | goto out; | |
1517 | } | |
1518 | state->private = private; | |
1519 | out: | |
cad321ad | 1520 | spin_unlock(&tree->lock); |
d1310b2e CM |
1521 | return ret; |
1522 | } | |
1523 | ||
1524 | int get_state_private(struct extent_io_tree *tree, u64 start, u64 *private) | |
1525 | { | |
1526 | struct rb_node *node; | |
1527 | struct extent_state *state; | |
1528 | int ret = 0; | |
1529 | ||
cad321ad | 1530 | spin_lock(&tree->lock); |
d1310b2e CM |
1531 | /* |
1532 | * this search will find all the extents that end after | |
1533 | * our range starts. | |
1534 | */ | |
80ea96b1 | 1535 | node = tree_search(tree, start); |
2b114d1d | 1536 | if (!node) { |
d1310b2e CM |
1537 | ret = -ENOENT; |
1538 | goto out; | |
1539 | } | |
1540 | state = rb_entry(node, struct extent_state, rb_node); | |
1541 | if (state->start != start) { | |
1542 | ret = -ENOENT; | |
1543 | goto out; | |
1544 | } | |
1545 | *private = state->private; | |
1546 | out: | |
cad321ad | 1547 | spin_unlock(&tree->lock); |
d1310b2e CM |
1548 | return ret; |
1549 | } | |
1550 | ||
1551 | /* | |
1552 | * searches a range in the state tree for a given mask. | |
70dec807 | 1553 | * If 'filled' == 1, this returns 1 only if every extent in the tree |
d1310b2e CM |
1554 | * has the bits set. Otherwise, 1 is returned if any bit in the |
1555 | * range is found set. | |
1556 | */ | |
1557 | int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end, | |
9655d298 | 1558 | int bits, int filled, struct extent_state *cached) |
d1310b2e CM |
1559 | { |
1560 | struct extent_state *state = NULL; | |
1561 | struct rb_node *node; | |
1562 | int bitset = 0; | |
d1310b2e | 1563 | |
cad321ad | 1564 | spin_lock(&tree->lock); |
9655d298 CM |
1565 | if (cached && cached->tree && cached->start == start) |
1566 | node = &cached->rb_node; | |
1567 | else | |
1568 | node = tree_search(tree, start); | |
d1310b2e CM |
1569 | while (node && start <= end) { |
1570 | state = rb_entry(node, struct extent_state, rb_node); | |
1571 | ||
1572 | if (filled && state->start > start) { | |
1573 | bitset = 0; | |
1574 | break; | |
1575 | } | |
1576 | ||
1577 | if (state->start > end) | |
1578 | break; | |
1579 | ||
1580 | if (state->state & bits) { | |
1581 | bitset = 1; | |
1582 | if (!filled) | |
1583 | break; | |
1584 | } else if (filled) { | |
1585 | bitset = 0; | |
1586 | break; | |
1587 | } | |
46562cec CM |
1588 | |
1589 | if (state->end == (u64)-1) | |
1590 | break; | |
1591 | ||
d1310b2e CM |
1592 | start = state->end + 1; |
1593 | if (start > end) | |
1594 | break; | |
1595 | node = rb_next(node); | |
1596 | if (!node) { | |
1597 | if (filled) | |
1598 | bitset = 0; | |
1599 | break; | |
1600 | } | |
1601 | } | |
cad321ad | 1602 | spin_unlock(&tree->lock); |
d1310b2e CM |
1603 | return bitset; |
1604 | } | |
d1310b2e CM |
1605 | |
1606 | /* | |
1607 | * helper function to set a given page up to date if all the | |
1608 | * extents in the tree for that page are up to date | |
1609 | */ | |
1610 | static int check_page_uptodate(struct extent_io_tree *tree, | |
1611 | struct page *page) | |
1612 | { | |
1613 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
1614 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
9655d298 | 1615 | if (test_range_bit(tree, start, end, EXTENT_UPTODATE, 1, NULL)) |
d1310b2e CM |
1616 | SetPageUptodate(page); |
1617 | return 0; | |
1618 | } | |
1619 | ||
1620 | /* | |
1621 | * helper function to unlock a page if all the extents in the tree | |
1622 | * for that page are unlocked | |
1623 | */ | |
1624 | static int check_page_locked(struct extent_io_tree *tree, | |
1625 | struct page *page) | |
1626 | { | |
1627 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
1628 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
9655d298 | 1629 | if (!test_range_bit(tree, start, end, EXTENT_LOCKED, 0, NULL)) |
d1310b2e CM |
1630 | unlock_page(page); |
1631 | return 0; | |
1632 | } | |
1633 | ||
1634 | /* | |
1635 | * helper function to end page writeback if all the extents | |
1636 | * in the tree for that page are done with writeback | |
1637 | */ | |
1638 | static int check_page_writeback(struct extent_io_tree *tree, | |
1639 | struct page *page) | |
1640 | { | |
1edbb734 | 1641 | end_page_writeback(page); |
d1310b2e CM |
1642 | return 0; |
1643 | } | |
1644 | ||
1645 | /* lots and lots of room for performance fixes in the end_bio funcs */ | |
1646 | ||
1647 | /* | |
1648 | * after a writepage IO is done, we need to: | |
1649 | * clear the uptodate bits on error | |
1650 | * clear the writeback bits in the extent tree for this IO | |
1651 | * end_page_writeback if the page has no more pending IO | |
1652 | * | |
1653 | * Scheduling is not allowed, so the extent state tree is expected | |
1654 | * to have one and only one object corresponding to this IO. | |
1655 | */ | |
d1310b2e | 1656 | static void end_bio_extent_writepage(struct bio *bio, int err) |
d1310b2e | 1657 | { |
1259ab75 | 1658 | int uptodate = err == 0; |
d1310b2e | 1659 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; |
902b22f3 | 1660 | struct extent_io_tree *tree; |
d1310b2e CM |
1661 | u64 start; |
1662 | u64 end; | |
1663 | int whole_page; | |
1259ab75 | 1664 | int ret; |
d1310b2e | 1665 | |
d1310b2e CM |
1666 | do { |
1667 | struct page *page = bvec->bv_page; | |
902b22f3 DW |
1668 | tree = &BTRFS_I(page->mapping->host)->io_tree; |
1669 | ||
d1310b2e CM |
1670 | start = ((u64)page->index << PAGE_CACHE_SHIFT) + |
1671 | bvec->bv_offset; | |
1672 | end = start + bvec->bv_len - 1; | |
1673 | ||
1674 | if (bvec->bv_offset == 0 && bvec->bv_len == PAGE_CACHE_SIZE) | |
1675 | whole_page = 1; | |
1676 | else | |
1677 | whole_page = 0; | |
1678 | ||
1679 | if (--bvec >= bio->bi_io_vec) | |
1680 | prefetchw(&bvec->bv_page->flags); | |
1259ab75 CM |
1681 | if (tree->ops && tree->ops->writepage_end_io_hook) { |
1682 | ret = tree->ops->writepage_end_io_hook(page, start, | |
902b22f3 | 1683 | end, NULL, uptodate); |
1259ab75 CM |
1684 | if (ret) |
1685 | uptodate = 0; | |
1686 | } | |
1687 | ||
1688 | if (!uptodate && tree->ops && | |
1689 | tree->ops->writepage_io_failed_hook) { | |
1690 | ret = tree->ops->writepage_io_failed_hook(bio, page, | |
902b22f3 | 1691 | start, end, NULL); |
1259ab75 | 1692 | if (ret == 0) { |
1259ab75 CM |
1693 | uptodate = (err == 0); |
1694 | continue; | |
1695 | } | |
1696 | } | |
1697 | ||
d1310b2e | 1698 | if (!uptodate) { |
2ac55d41 | 1699 | clear_extent_uptodate(tree, start, end, NULL, GFP_NOFS); |
d1310b2e CM |
1700 | ClearPageUptodate(page); |
1701 | SetPageError(page); | |
1702 | } | |
70dec807 | 1703 | |
d1310b2e CM |
1704 | if (whole_page) |
1705 | end_page_writeback(page); | |
1706 | else | |
1707 | check_page_writeback(tree, page); | |
d1310b2e | 1708 | } while (bvec >= bio->bi_io_vec); |
2b1f55b0 | 1709 | |
d1310b2e | 1710 | bio_put(bio); |
d1310b2e CM |
1711 | } |
1712 | ||
1713 | /* | |
1714 | * after a readpage IO is done, we need to: | |
1715 | * clear the uptodate bits on error | |
1716 | * set the uptodate bits if things worked | |
1717 | * set the page up to date if all extents in the tree are uptodate | |
1718 | * clear the lock bit in the extent tree | |
1719 | * unlock the page if there are no other extents locked for it | |
1720 | * | |
1721 | * Scheduling is not allowed, so the extent state tree is expected | |
1722 | * to have one and only one object corresponding to this IO. | |
1723 | */ | |
d1310b2e | 1724 | static void end_bio_extent_readpage(struct bio *bio, int err) |
d1310b2e CM |
1725 | { |
1726 | int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); | |
4125bf76 CM |
1727 | struct bio_vec *bvec_end = bio->bi_io_vec + bio->bi_vcnt - 1; |
1728 | struct bio_vec *bvec = bio->bi_io_vec; | |
902b22f3 | 1729 | struct extent_io_tree *tree; |
d1310b2e CM |
1730 | u64 start; |
1731 | u64 end; | |
1732 | int whole_page; | |
1733 | int ret; | |
1734 | ||
d20f7043 CM |
1735 | if (err) |
1736 | uptodate = 0; | |
1737 | ||
d1310b2e CM |
1738 | do { |
1739 | struct page *page = bvec->bv_page; | |
507903b8 AJ |
1740 | struct extent_state *cached = NULL; |
1741 | struct extent_state *state; | |
1742 | ||
902b22f3 DW |
1743 | tree = &BTRFS_I(page->mapping->host)->io_tree; |
1744 | ||
d1310b2e CM |
1745 | start = ((u64)page->index << PAGE_CACHE_SHIFT) + |
1746 | bvec->bv_offset; | |
1747 | end = start + bvec->bv_len - 1; | |
1748 | ||
1749 | if (bvec->bv_offset == 0 && bvec->bv_len == PAGE_CACHE_SIZE) | |
1750 | whole_page = 1; | |
1751 | else | |
1752 | whole_page = 0; | |
1753 | ||
4125bf76 | 1754 | if (++bvec <= bvec_end) |
d1310b2e CM |
1755 | prefetchw(&bvec->bv_page->flags); |
1756 | ||
507903b8 | 1757 | spin_lock(&tree->lock); |
0d399205 | 1758 | state = find_first_extent_bit_state(tree, start, EXTENT_LOCKED); |
109b36a2 | 1759 | if (state && state->start == start) { |
507903b8 AJ |
1760 | /* |
1761 | * take a reference on the state, unlock will drop | |
1762 | * the ref | |
1763 | */ | |
1764 | cache_state(state, &cached); | |
1765 | } | |
1766 | spin_unlock(&tree->lock); | |
1767 | ||
d1310b2e | 1768 | if (uptodate && tree->ops && tree->ops->readpage_end_io_hook) { |
70dec807 | 1769 | ret = tree->ops->readpage_end_io_hook(page, start, end, |
507903b8 | 1770 | state); |
d1310b2e CM |
1771 | if (ret) |
1772 | uptodate = 0; | |
1773 | } | |
7e38326f CM |
1774 | if (!uptodate && tree->ops && |
1775 | tree->ops->readpage_io_failed_hook) { | |
1776 | ret = tree->ops->readpage_io_failed_hook(bio, page, | |
902b22f3 | 1777 | start, end, NULL); |
7e38326f | 1778 | if (ret == 0) { |
3b951516 CM |
1779 | uptodate = |
1780 | test_bit(BIO_UPTODATE, &bio->bi_flags); | |
d20f7043 CM |
1781 | if (err) |
1782 | uptodate = 0; | |
507903b8 | 1783 | uncache_state(&cached); |
7e38326f CM |
1784 | continue; |
1785 | } | |
1786 | } | |
d1310b2e | 1787 | |
771ed689 | 1788 | if (uptodate) { |
507903b8 | 1789 | set_extent_uptodate(tree, start, end, &cached, |
902b22f3 | 1790 | GFP_ATOMIC); |
771ed689 | 1791 | } |
507903b8 | 1792 | unlock_extent_cached(tree, start, end, &cached, GFP_ATOMIC); |
d1310b2e | 1793 | |
70dec807 CM |
1794 | if (whole_page) { |
1795 | if (uptodate) { | |
1796 | SetPageUptodate(page); | |
1797 | } else { | |
1798 | ClearPageUptodate(page); | |
1799 | SetPageError(page); | |
1800 | } | |
d1310b2e | 1801 | unlock_page(page); |
70dec807 CM |
1802 | } else { |
1803 | if (uptodate) { | |
1804 | check_page_uptodate(tree, page); | |
1805 | } else { | |
1806 | ClearPageUptodate(page); | |
1807 | SetPageError(page); | |
1808 | } | |
d1310b2e | 1809 | check_page_locked(tree, page); |
70dec807 | 1810 | } |
4125bf76 | 1811 | } while (bvec <= bvec_end); |
d1310b2e CM |
1812 | |
1813 | bio_put(bio); | |
d1310b2e CM |
1814 | } |
1815 | ||
88f794ed MX |
1816 | struct bio * |
1817 | btrfs_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs, | |
1818 | gfp_t gfp_flags) | |
d1310b2e CM |
1819 | { |
1820 | struct bio *bio; | |
1821 | ||
1822 | bio = bio_alloc(gfp_flags, nr_vecs); | |
1823 | ||
1824 | if (bio == NULL && (current->flags & PF_MEMALLOC)) { | |
1825 | while (!bio && (nr_vecs /= 2)) | |
1826 | bio = bio_alloc(gfp_flags, nr_vecs); | |
1827 | } | |
1828 | ||
1829 | if (bio) { | |
e1c4b745 | 1830 | bio->bi_size = 0; |
d1310b2e CM |
1831 | bio->bi_bdev = bdev; |
1832 | bio->bi_sector = first_sector; | |
1833 | } | |
1834 | return bio; | |
1835 | } | |
1836 | ||
c8b97818 CM |
1837 | static int submit_one_bio(int rw, struct bio *bio, int mirror_num, |
1838 | unsigned long bio_flags) | |
d1310b2e | 1839 | { |
d1310b2e | 1840 | int ret = 0; |
70dec807 CM |
1841 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; |
1842 | struct page *page = bvec->bv_page; | |
1843 | struct extent_io_tree *tree = bio->bi_private; | |
70dec807 | 1844 | u64 start; |
70dec807 CM |
1845 | |
1846 | start = ((u64)page->index << PAGE_CACHE_SHIFT) + bvec->bv_offset; | |
70dec807 | 1847 | |
902b22f3 | 1848 | bio->bi_private = NULL; |
d1310b2e CM |
1849 | |
1850 | bio_get(bio); | |
1851 | ||
065631f6 | 1852 | if (tree->ops && tree->ops->submit_bio_hook) |
6b82ce8d | 1853 | ret = tree->ops->submit_bio_hook(page->mapping->host, rw, bio, |
eaf25d93 | 1854 | mirror_num, bio_flags, start); |
0b86a832 CM |
1855 | else |
1856 | submit_bio(rw, bio); | |
d1310b2e CM |
1857 | if (bio_flagged(bio, BIO_EOPNOTSUPP)) |
1858 | ret = -EOPNOTSUPP; | |
1859 | bio_put(bio); | |
1860 | return ret; | |
1861 | } | |
1862 | ||
1863 | static int submit_extent_page(int rw, struct extent_io_tree *tree, | |
1864 | struct page *page, sector_t sector, | |
1865 | size_t size, unsigned long offset, | |
1866 | struct block_device *bdev, | |
1867 | struct bio **bio_ret, | |
1868 | unsigned long max_pages, | |
f188591e | 1869 | bio_end_io_t end_io_func, |
c8b97818 CM |
1870 | int mirror_num, |
1871 | unsigned long prev_bio_flags, | |
1872 | unsigned long bio_flags) | |
d1310b2e CM |
1873 | { |
1874 | int ret = 0; | |
1875 | struct bio *bio; | |
1876 | int nr; | |
c8b97818 CM |
1877 | int contig = 0; |
1878 | int this_compressed = bio_flags & EXTENT_BIO_COMPRESSED; | |
1879 | int old_compressed = prev_bio_flags & EXTENT_BIO_COMPRESSED; | |
5b050f04 | 1880 | size_t page_size = min_t(size_t, size, PAGE_CACHE_SIZE); |
d1310b2e CM |
1881 | |
1882 | if (bio_ret && *bio_ret) { | |
1883 | bio = *bio_ret; | |
c8b97818 CM |
1884 | if (old_compressed) |
1885 | contig = bio->bi_sector == sector; | |
1886 | else | |
1887 | contig = bio->bi_sector + (bio->bi_size >> 9) == | |
1888 | sector; | |
1889 | ||
1890 | if (prev_bio_flags != bio_flags || !contig || | |
239b14b3 | 1891 | (tree->ops && tree->ops->merge_bio_hook && |
c8b97818 CM |
1892 | tree->ops->merge_bio_hook(page, offset, page_size, bio, |
1893 | bio_flags)) || | |
1894 | bio_add_page(bio, page, page_size, offset) < page_size) { | |
1895 | ret = submit_one_bio(rw, bio, mirror_num, | |
1896 | prev_bio_flags); | |
d1310b2e CM |
1897 | bio = NULL; |
1898 | } else { | |
1899 | return 0; | |
1900 | } | |
1901 | } | |
c8b97818 CM |
1902 | if (this_compressed) |
1903 | nr = BIO_MAX_PAGES; | |
1904 | else | |
1905 | nr = bio_get_nr_vecs(bdev); | |
1906 | ||
88f794ed | 1907 | bio = btrfs_bio_alloc(bdev, sector, nr, GFP_NOFS | __GFP_HIGH); |
5df67083 TI |
1908 | if (!bio) |
1909 | return -ENOMEM; | |
70dec807 | 1910 | |
c8b97818 | 1911 | bio_add_page(bio, page, page_size, offset); |
d1310b2e CM |
1912 | bio->bi_end_io = end_io_func; |
1913 | bio->bi_private = tree; | |
70dec807 | 1914 | |
d397712b | 1915 | if (bio_ret) |
d1310b2e | 1916 | *bio_ret = bio; |
d397712b | 1917 | else |
c8b97818 | 1918 | ret = submit_one_bio(rw, bio, mirror_num, bio_flags); |
d1310b2e CM |
1919 | |
1920 | return ret; | |
1921 | } | |
1922 | ||
1923 | void set_page_extent_mapped(struct page *page) | |
1924 | { | |
1925 | if (!PagePrivate(page)) { | |
1926 | SetPagePrivate(page); | |
d1310b2e | 1927 | page_cache_get(page); |
6af118ce | 1928 | set_page_private(page, EXTENT_PAGE_PRIVATE); |
d1310b2e CM |
1929 | } |
1930 | } | |
1931 | ||
b2950863 | 1932 | static void set_page_extent_head(struct page *page, unsigned long len) |
d1310b2e | 1933 | { |
eb14ab8e | 1934 | WARN_ON(!PagePrivate(page)); |
d1310b2e CM |
1935 | set_page_private(page, EXTENT_PAGE_PRIVATE_FIRST_PAGE | len << 2); |
1936 | } | |
1937 | ||
1938 | /* | |
1939 | * basic readpage implementation. Locked extent state structs are inserted | |
1940 | * into the tree that are removed when the IO is done (by the end_io | |
1941 | * handlers) | |
1942 | */ | |
1943 | static int __extent_read_full_page(struct extent_io_tree *tree, | |
1944 | struct page *page, | |
1945 | get_extent_t *get_extent, | |
c8b97818 CM |
1946 | struct bio **bio, int mirror_num, |
1947 | unsigned long *bio_flags) | |
d1310b2e CM |
1948 | { |
1949 | struct inode *inode = page->mapping->host; | |
1950 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
1951 | u64 page_end = start + PAGE_CACHE_SIZE - 1; | |
1952 | u64 end; | |
1953 | u64 cur = start; | |
1954 | u64 extent_offset; | |
1955 | u64 last_byte = i_size_read(inode); | |
1956 | u64 block_start; | |
1957 | u64 cur_end; | |
1958 | sector_t sector; | |
1959 | struct extent_map *em; | |
1960 | struct block_device *bdev; | |
11c65dcc | 1961 | struct btrfs_ordered_extent *ordered; |
d1310b2e CM |
1962 | int ret; |
1963 | int nr = 0; | |
306e16ce | 1964 | size_t pg_offset = 0; |
d1310b2e | 1965 | size_t iosize; |
c8b97818 | 1966 | size_t disk_io_size; |
d1310b2e | 1967 | size_t blocksize = inode->i_sb->s_blocksize; |
c8b97818 | 1968 | unsigned long this_bio_flag = 0; |
d1310b2e CM |
1969 | |
1970 | set_page_extent_mapped(page); | |
1971 | ||
1972 | end = page_end; | |
11c65dcc JB |
1973 | while (1) { |
1974 | lock_extent(tree, start, end, GFP_NOFS); | |
1975 | ordered = btrfs_lookup_ordered_extent(inode, start); | |
1976 | if (!ordered) | |
1977 | break; | |
1978 | unlock_extent(tree, start, end, GFP_NOFS); | |
1979 | btrfs_start_ordered_extent(inode, ordered, 1); | |
1980 | btrfs_put_ordered_extent(ordered); | |
1981 | } | |
d1310b2e | 1982 | |
c8b97818 CM |
1983 | if (page->index == last_byte >> PAGE_CACHE_SHIFT) { |
1984 | char *userpage; | |
1985 | size_t zero_offset = last_byte & (PAGE_CACHE_SIZE - 1); | |
1986 | ||
1987 | if (zero_offset) { | |
1988 | iosize = PAGE_CACHE_SIZE - zero_offset; | |
1989 | userpage = kmap_atomic(page, KM_USER0); | |
1990 | memset(userpage + zero_offset, 0, iosize); | |
1991 | flush_dcache_page(page); | |
1992 | kunmap_atomic(userpage, KM_USER0); | |
1993 | } | |
1994 | } | |
d1310b2e CM |
1995 | while (cur <= end) { |
1996 | if (cur >= last_byte) { | |
1997 | char *userpage; | |
507903b8 AJ |
1998 | struct extent_state *cached = NULL; |
1999 | ||
306e16ce | 2000 | iosize = PAGE_CACHE_SIZE - pg_offset; |
d1310b2e | 2001 | userpage = kmap_atomic(page, KM_USER0); |
306e16ce | 2002 | memset(userpage + pg_offset, 0, iosize); |
d1310b2e CM |
2003 | flush_dcache_page(page); |
2004 | kunmap_atomic(userpage, KM_USER0); | |
2005 | set_extent_uptodate(tree, cur, cur + iosize - 1, | |
507903b8 AJ |
2006 | &cached, GFP_NOFS); |
2007 | unlock_extent_cached(tree, cur, cur + iosize - 1, | |
2008 | &cached, GFP_NOFS); | |
d1310b2e CM |
2009 | break; |
2010 | } | |
306e16ce | 2011 | em = get_extent(inode, page, pg_offset, cur, |
d1310b2e | 2012 | end - cur + 1, 0); |
c704005d | 2013 | if (IS_ERR_OR_NULL(em)) { |
d1310b2e CM |
2014 | SetPageError(page); |
2015 | unlock_extent(tree, cur, end, GFP_NOFS); | |
2016 | break; | |
2017 | } | |
d1310b2e CM |
2018 | extent_offset = cur - em->start; |
2019 | BUG_ON(extent_map_end(em) <= cur); | |
2020 | BUG_ON(end < cur); | |
2021 | ||
261507a0 | 2022 | if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) { |
c8b97818 | 2023 | this_bio_flag = EXTENT_BIO_COMPRESSED; |
261507a0 LZ |
2024 | extent_set_compress_type(&this_bio_flag, |
2025 | em->compress_type); | |
2026 | } | |
c8b97818 | 2027 | |
d1310b2e CM |
2028 | iosize = min(extent_map_end(em) - cur, end - cur + 1); |
2029 | cur_end = min(extent_map_end(em) - 1, end); | |
2030 | iosize = (iosize + blocksize - 1) & ~((u64)blocksize - 1); | |
c8b97818 CM |
2031 | if (this_bio_flag & EXTENT_BIO_COMPRESSED) { |
2032 | disk_io_size = em->block_len; | |
2033 | sector = em->block_start >> 9; | |
2034 | } else { | |
2035 | sector = (em->block_start + extent_offset) >> 9; | |
2036 | disk_io_size = iosize; | |
2037 | } | |
d1310b2e CM |
2038 | bdev = em->bdev; |
2039 | block_start = em->block_start; | |
d899e052 YZ |
2040 | if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) |
2041 | block_start = EXTENT_MAP_HOLE; | |
d1310b2e CM |
2042 | free_extent_map(em); |
2043 | em = NULL; | |
2044 | ||
2045 | /* we've found a hole, just zero and go on */ | |
2046 | if (block_start == EXTENT_MAP_HOLE) { | |
2047 | char *userpage; | |
507903b8 AJ |
2048 | struct extent_state *cached = NULL; |
2049 | ||
d1310b2e | 2050 | userpage = kmap_atomic(page, KM_USER0); |
306e16ce | 2051 | memset(userpage + pg_offset, 0, iosize); |
d1310b2e CM |
2052 | flush_dcache_page(page); |
2053 | kunmap_atomic(userpage, KM_USER0); | |
2054 | ||
2055 | set_extent_uptodate(tree, cur, cur + iosize - 1, | |
507903b8 AJ |
2056 | &cached, GFP_NOFS); |
2057 | unlock_extent_cached(tree, cur, cur + iosize - 1, | |
2058 | &cached, GFP_NOFS); | |
d1310b2e | 2059 | cur = cur + iosize; |
306e16ce | 2060 | pg_offset += iosize; |
d1310b2e CM |
2061 | continue; |
2062 | } | |
2063 | /* the get_extent function already copied into the page */ | |
9655d298 CM |
2064 | if (test_range_bit(tree, cur, cur_end, |
2065 | EXTENT_UPTODATE, 1, NULL)) { | |
a1b32a59 | 2066 | check_page_uptodate(tree, page); |
d1310b2e CM |
2067 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); |
2068 | cur = cur + iosize; | |
306e16ce | 2069 | pg_offset += iosize; |
d1310b2e CM |
2070 | continue; |
2071 | } | |
70dec807 CM |
2072 | /* we have an inline extent but it didn't get marked up |
2073 | * to date. Error out | |
2074 | */ | |
2075 | if (block_start == EXTENT_MAP_INLINE) { | |
2076 | SetPageError(page); | |
2077 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); | |
2078 | cur = cur + iosize; | |
306e16ce | 2079 | pg_offset += iosize; |
70dec807 CM |
2080 | continue; |
2081 | } | |
d1310b2e CM |
2082 | |
2083 | ret = 0; | |
2084 | if (tree->ops && tree->ops->readpage_io_hook) { | |
2085 | ret = tree->ops->readpage_io_hook(page, cur, | |
2086 | cur + iosize - 1); | |
2087 | } | |
2088 | if (!ret) { | |
89642229 CM |
2089 | unsigned long pnr = (last_byte >> PAGE_CACHE_SHIFT) + 1; |
2090 | pnr -= page->index; | |
d1310b2e | 2091 | ret = submit_extent_page(READ, tree, page, |
306e16ce | 2092 | sector, disk_io_size, pg_offset, |
89642229 | 2093 | bdev, bio, pnr, |
c8b97818 CM |
2094 | end_bio_extent_readpage, mirror_num, |
2095 | *bio_flags, | |
2096 | this_bio_flag); | |
89642229 | 2097 | nr++; |
c8b97818 | 2098 | *bio_flags = this_bio_flag; |
d1310b2e CM |
2099 | } |
2100 | if (ret) | |
2101 | SetPageError(page); | |
2102 | cur = cur + iosize; | |
306e16ce | 2103 | pg_offset += iosize; |
d1310b2e CM |
2104 | } |
2105 | if (!nr) { | |
2106 | if (!PageError(page)) | |
2107 | SetPageUptodate(page); | |
2108 | unlock_page(page); | |
2109 | } | |
2110 | return 0; | |
2111 | } | |
2112 | ||
2113 | int extent_read_full_page(struct extent_io_tree *tree, struct page *page, | |
2114 | get_extent_t *get_extent) | |
2115 | { | |
2116 | struct bio *bio = NULL; | |
c8b97818 | 2117 | unsigned long bio_flags = 0; |
d1310b2e CM |
2118 | int ret; |
2119 | ||
c8b97818 CM |
2120 | ret = __extent_read_full_page(tree, page, get_extent, &bio, 0, |
2121 | &bio_flags); | |
d1310b2e | 2122 | if (bio) |
6b82ce8d | 2123 | ret = submit_one_bio(READ, bio, 0, bio_flags); |
d1310b2e CM |
2124 | return ret; |
2125 | } | |
d1310b2e | 2126 | |
11c8349b CM |
2127 | static noinline void update_nr_written(struct page *page, |
2128 | struct writeback_control *wbc, | |
2129 | unsigned long nr_written) | |
2130 | { | |
2131 | wbc->nr_to_write -= nr_written; | |
2132 | if (wbc->range_cyclic || (wbc->nr_to_write > 0 && | |
2133 | wbc->range_start == 0 && wbc->range_end == LLONG_MAX)) | |
2134 | page->mapping->writeback_index = page->index + nr_written; | |
2135 | } | |
2136 | ||
d1310b2e CM |
2137 | /* |
2138 | * the writepage semantics are similar to regular writepage. extent | |
2139 | * records are inserted to lock ranges in the tree, and as dirty areas | |
2140 | * are found, they are marked writeback. Then the lock bits are removed | |
2141 | * and the end_io handler clears the writeback ranges | |
2142 | */ | |
2143 | static int __extent_writepage(struct page *page, struct writeback_control *wbc, | |
2144 | void *data) | |
2145 | { | |
2146 | struct inode *inode = page->mapping->host; | |
2147 | struct extent_page_data *epd = data; | |
2148 | struct extent_io_tree *tree = epd->tree; | |
2149 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
2150 | u64 delalloc_start; | |
2151 | u64 page_end = start + PAGE_CACHE_SIZE - 1; | |
2152 | u64 end; | |
2153 | u64 cur = start; | |
2154 | u64 extent_offset; | |
2155 | u64 last_byte = i_size_read(inode); | |
2156 | u64 block_start; | |
2157 | u64 iosize; | |
2158 | sector_t sector; | |
2c64c53d | 2159 | struct extent_state *cached_state = NULL; |
d1310b2e CM |
2160 | struct extent_map *em; |
2161 | struct block_device *bdev; | |
2162 | int ret; | |
2163 | int nr = 0; | |
7f3c74fb | 2164 | size_t pg_offset = 0; |
d1310b2e CM |
2165 | size_t blocksize; |
2166 | loff_t i_size = i_size_read(inode); | |
2167 | unsigned long end_index = i_size >> PAGE_CACHE_SHIFT; | |
2168 | u64 nr_delalloc; | |
2169 | u64 delalloc_end; | |
c8b97818 CM |
2170 | int page_started; |
2171 | int compressed; | |
ffbd517d | 2172 | int write_flags; |
771ed689 | 2173 | unsigned long nr_written = 0; |
d1310b2e | 2174 | |
ffbd517d | 2175 | if (wbc->sync_mode == WB_SYNC_ALL) |
721a9602 | 2176 | write_flags = WRITE_SYNC; |
ffbd517d CM |
2177 | else |
2178 | write_flags = WRITE; | |
2179 | ||
1abe9b8a | 2180 | trace___extent_writepage(page, inode, wbc); |
2181 | ||
d1310b2e | 2182 | WARN_ON(!PageLocked(page)); |
7f3c74fb | 2183 | pg_offset = i_size & (PAGE_CACHE_SIZE - 1); |
211c17f5 | 2184 | if (page->index > end_index || |
7f3c74fb | 2185 | (page->index == end_index && !pg_offset)) { |
39be25cd | 2186 | page->mapping->a_ops->invalidatepage(page, 0); |
d1310b2e CM |
2187 | unlock_page(page); |
2188 | return 0; | |
2189 | } | |
2190 | ||
2191 | if (page->index == end_index) { | |
2192 | char *userpage; | |
2193 | ||
d1310b2e | 2194 | userpage = kmap_atomic(page, KM_USER0); |
7f3c74fb CM |
2195 | memset(userpage + pg_offset, 0, |
2196 | PAGE_CACHE_SIZE - pg_offset); | |
d1310b2e | 2197 | kunmap_atomic(userpage, KM_USER0); |
211c17f5 | 2198 | flush_dcache_page(page); |
d1310b2e | 2199 | } |
7f3c74fb | 2200 | pg_offset = 0; |
d1310b2e CM |
2201 | |
2202 | set_page_extent_mapped(page); | |
2203 | ||
2204 | delalloc_start = start; | |
2205 | delalloc_end = 0; | |
c8b97818 | 2206 | page_started = 0; |
771ed689 | 2207 | if (!epd->extent_locked) { |
f85d7d6c | 2208 | u64 delalloc_to_write = 0; |
11c8349b CM |
2209 | /* |
2210 | * make sure the wbc mapping index is at least updated | |
2211 | * to this page. | |
2212 | */ | |
2213 | update_nr_written(page, wbc, 0); | |
2214 | ||
d397712b | 2215 | while (delalloc_end < page_end) { |
771ed689 | 2216 | nr_delalloc = find_lock_delalloc_range(inode, tree, |
c8b97818 CM |
2217 | page, |
2218 | &delalloc_start, | |
d1310b2e CM |
2219 | &delalloc_end, |
2220 | 128 * 1024 * 1024); | |
771ed689 CM |
2221 | if (nr_delalloc == 0) { |
2222 | delalloc_start = delalloc_end + 1; | |
2223 | continue; | |
2224 | } | |
2225 | tree->ops->fill_delalloc(inode, page, delalloc_start, | |
2226 | delalloc_end, &page_started, | |
2227 | &nr_written); | |
f85d7d6c CM |
2228 | /* |
2229 | * delalloc_end is already one less than the total | |
2230 | * length, so we don't subtract one from | |
2231 | * PAGE_CACHE_SIZE | |
2232 | */ | |
2233 | delalloc_to_write += (delalloc_end - delalloc_start + | |
2234 | PAGE_CACHE_SIZE) >> | |
2235 | PAGE_CACHE_SHIFT; | |
d1310b2e | 2236 | delalloc_start = delalloc_end + 1; |
d1310b2e | 2237 | } |
f85d7d6c CM |
2238 | if (wbc->nr_to_write < delalloc_to_write) { |
2239 | int thresh = 8192; | |
2240 | ||
2241 | if (delalloc_to_write < thresh * 2) | |
2242 | thresh = delalloc_to_write; | |
2243 | wbc->nr_to_write = min_t(u64, delalloc_to_write, | |
2244 | thresh); | |
2245 | } | |
c8b97818 | 2246 | |
771ed689 CM |
2247 | /* did the fill delalloc function already unlock and start |
2248 | * the IO? | |
2249 | */ | |
2250 | if (page_started) { | |
2251 | ret = 0; | |
11c8349b CM |
2252 | /* |
2253 | * we've unlocked the page, so we can't update | |
2254 | * the mapping's writeback index, just update | |
2255 | * nr_to_write. | |
2256 | */ | |
2257 | wbc->nr_to_write -= nr_written; | |
2258 | goto done_unlocked; | |
771ed689 | 2259 | } |
c8b97818 | 2260 | } |
247e743c | 2261 | if (tree->ops && tree->ops->writepage_start_hook) { |
c8b97818 CM |
2262 | ret = tree->ops->writepage_start_hook(page, start, |
2263 | page_end); | |
247e743c | 2264 | if (ret == -EAGAIN) { |
247e743c | 2265 | redirty_page_for_writepage(wbc, page); |
11c8349b | 2266 | update_nr_written(page, wbc, nr_written); |
247e743c | 2267 | unlock_page(page); |
771ed689 | 2268 | ret = 0; |
11c8349b | 2269 | goto done_unlocked; |
247e743c CM |
2270 | } |
2271 | } | |
2272 | ||
11c8349b CM |
2273 | /* |
2274 | * we don't want to touch the inode after unlocking the page, | |
2275 | * so we update the mapping writeback index now | |
2276 | */ | |
2277 | update_nr_written(page, wbc, nr_written + 1); | |
771ed689 | 2278 | |
d1310b2e | 2279 | end = page_end; |
d1310b2e | 2280 | if (last_byte <= start) { |
e6dcd2dc CM |
2281 | if (tree->ops && tree->ops->writepage_end_io_hook) |
2282 | tree->ops->writepage_end_io_hook(page, start, | |
2283 | page_end, NULL, 1); | |
d1310b2e CM |
2284 | goto done; |
2285 | } | |
2286 | ||
d1310b2e CM |
2287 | blocksize = inode->i_sb->s_blocksize; |
2288 | ||
2289 | while (cur <= end) { | |
2290 | if (cur >= last_byte) { | |
e6dcd2dc CM |
2291 | if (tree->ops && tree->ops->writepage_end_io_hook) |
2292 | tree->ops->writepage_end_io_hook(page, cur, | |
2293 | page_end, NULL, 1); | |
d1310b2e CM |
2294 | break; |
2295 | } | |
7f3c74fb | 2296 | em = epd->get_extent(inode, page, pg_offset, cur, |
d1310b2e | 2297 | end - cur + 1, 1); |
c704005d | 2298 | if (IS_ERR_OR_NULL(em)) { |
d1310b2e CM |
2299 | SetPageError(page); |
2300 | break; | |
2301 | } | |
2302 | ||
2303 | extent_offset = cur - em->start; | |
2304 | BUG_ON(extent_map_end(em) <= cur); | |
2305 | BUG_ON(end < cur); | |
2306 | iosize = min(extent_map_end(em) - cur, end - cur + 1); | |
2307 | iosize = (iosize + blocksize - 1) & ~((u64)blocksize - 1); | |
2308 | sector = (em->block_start + extent_offset) >> 9; | |
2309 | bdev = em->bdev; | |
2310 | block_start = em->block_start; | |
c8b97818 | 2311 | compressed = test_bit(EXTENT_FLAG_COMPRESSED, &em->flags); |
d1310b2e CM |
2312 | free_extent_map(em); |
2313 | em = NULL; | |
2314 | ||
c8b97818 CM |
2315 | /* |
2316 | * compressed and inline extents are written through other | |
2317 | * paths in the FS | |
2318 | */ | |
2319 | if (compressed || block_start == EXTENT_MAP_HOLE || | |
d1310b2e | 2320 | block_start == EXTENT_MAP_INLINE) { |
c8b97818 CM |
2321 | /* |
2322 | * end_io notification does not happen here for | |
2323 | * compressed extents | |
2324 | */ | |
2325 | if (!compressed && tree->ops && | |
2326 | tree->ops->writepage_end_io_hook) | |
e6dcd2dc CM |
2327 | tree->ops->writepage_end_io_hook(page, cur, |
2328 | cur + iosize - 1, | |
2329 | NULL, 1); | |
c8b97818 CM |
2330 | else if (compressed) { |
2331 | /* we don't want to end_page_writeback on | |
2332 | * a compressed extent. this happens | |
2333 | * elsewhere | |
2334 | */ | |
2335 | nr++; | |
2336 | } | |
2337 | ||
2338 | cur += iosize; | |
7f3c74fb | 2339 | pg_offset += iosize; |
d1310b2e CM |
2340 | continue; |
2341 | } | |
d1310b2e CM |
2342 | /* leave this out until we have a page_mkwrite call */ |
2343 | if (0 && !test_range_bit(tree, cur, cur + iosize - 1, | |
9655d298 | 2344 | EXTENT_DIRTY, 0, NULL)) { |
d1310b2e | 2345 | cur = cur + iosize; |
7f3c74fb | 2346 | pg_offset += iosize; |
d1310b2e CM |
2347 | continue; |
2348 | } | |
c8b97818 | 2349 | |
d1310b2e CM |
2350 | if (tree->ops && tree->ops->writepage_io_hook) { |
2351 | ret = tree->ops->writepage_io_hook(page, cur, | |
2352 | cur + iosize - 1); | |
2353 | } else { | |
2354 | ret = 0; | |
2355 | } | |
1259ab75 | 2356 | if (ret) { |
d1310b2e | 2357 | SetPageError(page); |
1259ab75 | 2358 | } else { |
d1310b2e | 2359 | unsigned long max_nr = end_index + 1; |
7f3c74fb | 2360 | |
d1310b2e CM |
2361 | set_range_writeback(tree, cur, cur + iosize - 1); |
2362 | if (!PageWriteback(page)) { | |
d397712b CM |
2363 | printk(KERN_ERR "btrfs warning page %lu not " |
2364 | "writeback, cur %llu end %llu\n", | |
2365 | page->index, (unsigned long long)cur, | |
d1310b2e CM |
2366 | (unsigned long long)end); |
2367 | } | |
2368 | ||
ffbd517d CM |
2369 | ret = submit_extent_page(write_flags, tree, page, |
2370 | sector, iosize, pg_offset, | |
2371 | bdev, &epd->bio, max_nr, | |
c8b97818 CM |
2372 | end_bio_extent_writepage, |
2373 | 0, 0, 0); | |
d1310b2e CM |
2374 | if (ret) |
2375 | SetPageError(page); | |
2376 | } | |
2377 | cur = cur + iosize; | |
7f3c74fb | 2378 | pg_offset += iosize; |
d1310b2e CM |
2379 | nr++; |
2380 | } | |
2381 | done: | |
2382 | if (nr == 0) { | |
2383 | /* make sure the mapping tag for page dirty gets cleared */ | |
2384 | set_page_writeback(page); | |
2385 | end_page_writeback(page); | |
2386 | } | |
d1310b2e | 2387 | unlock_page(page); |
771ed689 | 2388 | |
11c8349b CM |
2389 | done_unlocked: |
2390 | ||
2c64c53d CM |
2391 | /* drop our reference on any cached states */ |
2392 | free_extent_state(cached_state); | |
d1310b2e CM |
2393 | return 0; |
2394 | } | |
2395 | ||
d1310b2e | 2396 | /** |
4bef0848 | 2397 | * write_cache_pages - walk the list of dirty pages of the given address space and write all of them. |
d1310b2e CM |
2398 | * @mapping: address space structure to write |
2399 | * @wbc: subtract the number of written pages from *@wbc->nr_to_write | |
2400 | * @writepage: function called for each page | |
2401 | * @data: data passed to writepage function | |
2402 | * | |
2403 | * If a page is already under I/O, write_cache_pages() skips it, even | |
2404 | * if it's dirty. This is desirable behaviour for memory-cleaning writeback, | |
2405 | * but it is INCORRECT for data-integrity system calls such as fsync(). fsync() | |
2406 | * and msync() need to guarantee that all the data which was dirty at the time | |
2407 | * the call was made get new I/O started against them. If wbc->sync_mode is | |
2408 | * WB_SYNC_ALL then we were called for data integrity and we must wait for | |
2409 | * existing IO to complete. | |
2410 | */ | |
b2950863 | 2411 | static int extent_write_cache_pages(struct extent_io_tree *tree, |
4bef0848 CM |
2412 | struct address_space *mapping, |
2413 | struct writeback_control *wbc, | |
d2c3f4f6 CM |
2414 | writepage_t writepage, void *data, |
2415 | void (*flush_fn)(void *)) | |
d1310b2e | 2416 | { |
d1310b2e CM |
2417 | int ret = 0; |
2418 | int done = 0; | |
f85d7d6c | 2419 | int nr_to_write_done = 0; |
d1310b2e CM |
2420 | struct pagevec pvec; |
2421 | int nr_pages; | |
2422 | pgoff_t index; | |
2423 | pgoff_t end; /* Inclusive */ | |
2424 | int scanned = 0; | |
d1310b2e | 2425 | |
d1310b2e CM |
2426 | pagevec_init(&pvec, 0); |
2427 | if (wbc->range_cyclic) { | |
2428 | index = mapping->writeback_index; /* Start from prev offset */ | |
2429 | end = -1; | |
2430 | } else { | |
2431 | index = wbc->range_start >> PAGE_CACHE_SHIFT; | |
2432 | end = wbc->range_end >> PAGE_CACHE_SHIFT; | |
d1310b2e CM |
2433 | scanned = 1; |
2434 | } | |
2435 | retry: | |
f85d7d6c | 2436 | while (!done && !nr_to_write_done && (index <= end) && |
d1310b2e | 2437 | (nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, |
d397712b CM |
2438 | PAGECACHE_TAG_DIRTY, min(end - index, |
2439 | (pgoff_t)PAGEVEC_SIZE-1) + 1))) { | |
d1310b2e CM |
2440 | unsigned i; |
2441 | ||
2442 | scanned = 1; | |
2443 | for (i = 0; i < nr_pages; i++) { | |
2444 | struct page *page = pvec.pages[i]; | |
2445 | ||
2446 | /* | |
2447 | * At this point we hold neither mapping->tree_lock nor | |
2448 | * lock on the page itself: the page may be truncated or | |
2449 | * invalidated (changing page->mapping to NULL), or even | |
2450 | * swizzled back from swapper_space to tmpfs file | |
2451 | * mapping | |
2452 | */ | |
4bef0848 CM |
2453 | if (tree->ops && tree->ops->write_cache_pages_lock_hook) |
2454 | tree->ops->write_cache_pages_lock_hook(page); | |
2455 | else | |
2456 | lock_page(page); | |
d1310b2e CM |
2457 | |
2458 | if (unlikely(page->mapping != mapping)) { | |
2459 | unlock_page(page); | |
2460 | continue; | |
2461 | } | |
2462 | ||
2463 | if (!wbc->range_cyclic && page->index > end) { | |
2464 | done = 1; | |
2465 | unlock_page(page); | |
2466 | continue; | |
2467 | } | |
2468 | ||
d2c3f4f6 | 2469 | if (wbc->sync_mode != WB_SYNC_NONE) { |
0e6bd956 CM |
2470 | if (PageWriteback(page)) |
2471 | flush_fn(data); | |
d1310b2e | 2472 | wait_on_page_writeback(page); |
d2c3f4f6 | 2473 | } |
d1310b2e CM |
2474 | |
2475 | if (PageWriteback(page) || | |
2476 | !clear_page_dirty_for_io(page)) { | |
2477 | unlock_page(page); | |
2478 | continue; | |
2479 | } | |
2480 | ||
2481 | ret = (*writepage)(page, wbc, data); | |
2482 | ||
2483 | if (unlikely(ret == AOP_WRITEPAGE_ACTIVATE)) { | |
2484 | unlock_page(page); | |
2485 | ret = 0; | |
2486 | } | |
f85d7d6c | 2487 | if (ret) |
d1310b2e | 2488 | done = 1; |
f85d7d6c CM |
2489 | |
2490 | /* | |
2491 | * the filesystem may choose to bump up nr_to_write. | |
2492 | * We have to make sure to honor the new nr_to_write | |
2493 | * at any time | |
2494 | */ | |
2495 | nr_to_write_done = wbc->nr_to_write <= 0; | |
d1310b2e CM |
2496 | } |
2497 | pagevec_release(&pvec); | |
2498 | cond_resched(); | |
2499 | } | |
2500 | if (!scanned && !done) { | |
2501 | /* | |
2502 | * We hit the last page and there is more work to be done: wrap | |
2503 | * back to the start of the file | |
2504 | */ | |
2505 | scanned = 1; | |
2506 | index = 0; | |
2507 | goto retry; | |
2508 | } | |
d1310b2e CM |
2509 | return ret; |
2510 | } | |
d1310b2e | 2511 | |
ffbd517d | 2512 | static void flush_epd_write_bio(struct extent_page_data *epd) |
d2c3f4f6 | 2513 | { |
d2c3f4f6 | 2514 | if (epd->bio) { |
ffbd517d CM |
2515 | if (epd->sync_io) |
2516 | submit_one_bio(WRITE_SYNC, epd->bio, 0, 0); | |
2517 | else | |
2518 | submit_one_bio(WRITE, epd->bio, 0, 0); | |
d2c3f4f6 CM |
2519 | epd->bio = NULL; |
2520 | } | |
2521 | } | |
2522 | ||
ffbd517d CM |
2523 | static noinline void flush_write_bio(void *data) |
2524 | { | |
2525 | struct extent_page_data *epd = data; | |
2526 | flush_epd_write_bio(epd); | |
2527 | } | |
2528 | ||
d1310b2e CM |
2529 | int extent_write_full_page(struct extent_io_tree *tree, struct page *page, |
2530 | get_extent_t *get_extent, | |
2531 | struct writeback_control *wbc) | |
2532 | { | |
2533 | int ret; | |
2534 | struct address_space *mapping = page->mapping; | |
2535 | struct extent_page_data epd = { | |
2536 | .bio = NULL, | |
2537 | .tree = tree, | |
2538 | .get_extent = get_extent, | |
771ed689 | 2539 | .extent_locked = 0, |
ffbd517d | 2540 | .sync_io = wbc->sync_mode == WB_SYNC_ALL, |
d1310b2e CM |
2541 | }; |
2542 | struct writeback_control wbc_writepages = { | |
d313d7a3 | 2543 | .sync_mode = wbc->sync_mode, |
d1310b2e CM |
2544 | .older_than_this = NULL, |
2545 | .nr_to_write = 64, | |
2546 | .range_start = page_offset(page) + PAGE_CACHE_SIZE, | |
2547 | .range_end = (loff_t)-1, | |
2548 | }; | |
2549 | ||
d1310b2e CM |
2550 | ret = __extent_writepage(page, wbc, &epd); |
2551 | ||
4bef0848 | 2552 | extent_write_cache_pages(tree, mapping, &wbc_writepages, |
d2c3f4f6 | 2553 | __extent_writepage, &epd, flush_write_bio); |
ffbd517d | 2554 | flush_epd_write_bio(&epd); |
d1310b2e CM |
2555 | return ret; |
2556 | } | |
d1310b2e | 2557 | |
771ed689 CM |
2558 | int extent_write_locked_range(struct extent_io_tree *tree, struct inode *inode, |
2559 | u64 start, u64 end, get_extent_t *get_extent, | |
2560 | int mode) | |
2561 | { | |
2562 | int ret = 0; | |
2563 | struct address_space *mapping = inode->i_mapping; | |
2564 | struct page *page; | |
2565 | unsigned long nr_pages = (end - start + PAGE_CACHE_SIZE) >> | |
2566 | PAGE_CACHE_SHIFT; | |
2567 | ||
2568 | struct extent_page_data epd = { | |
2569 | .bio = NULL, | |
2570 | .tree = tree, | |
2571 | .get_extent = get_extent, | |
2572 | .extent_locked = 1, | |
ffbd517d | 2573 | .sync_io = mode == WB_SYNC_ALL, |
771ed689 CM |
2574 | }; |
2575 | struct writeback_control wbc_writepages = { | |
771ed689 CM |
2576 | .sync_mode = mode, |
2577 | .older_than_this = NULL, | |
2578 | .nr_to_write = nr_pages * 2, | |
2579 | .range_start = start, | |
2580 | .range_end = end + 1, | |
2581 | }; | |
2582 | ||
d397712b | 2583 | while (start <= end) { |
771ed689 CM |
2584 | page = find_get_page(mapping, start >> PAGE_CACHE_SHIFT); |
2585 | if (clear_page_dirty_for_io(page)) | |
2586 | ret = __extent_writepage(page, &wbc_writepages, &epd); | |
2587 | else { | |
2588 | if (tree->ops && tree->ops->writepage_end_io_hook) | |
2589 | tree->ops->writepage_end_io_hook(page, start, | |
2590 | start + PAGE_CACHE_SIZE - 1, | |
2591 | NULL, 1); | |
2592 | unlock_page(page); | |
2593 | } | |
2594 | page_cache_release(page); | |
2595 | start += PAGE_CACHE_SIZE; | |
2596 | } | |
2597 | ||
ffbd517d | 2598 | flush_epd_write_bio(&epd); |
771ed689 CM |
2599 | return ret; |
2600 | } | |
d1310b2e CM |
2601 | |
2602 | int extent_writepages(struct extent_io_tree *tree, | |
2603 | struct address_space *mapping, | |
2604 | get_extent_t *get_extent, | |
2605 | struct writeback_control *wbc) | |
2606 | { | |
2607 | int ret = 0; | |
2608 | struct extent_page_data epd = { | |
2609 | .bio = NULL, | |
2610 | .tree = tree, | |
2611 | .get_extent = get_extent, | |
771ed689 | 2612 | .extent_locked = 0, |
ffbd517d | 2613 | .sync_io = wbc->sync_mode == WB_SYNC_ALL, |
d1310b2e CM |
2614 | }; |
2615 | ||
4bef0848 | 2616 | ret = extent_write_cache_pages(tree, mapping, wbc, |
d2c3f4f6 CM |
2617 | __extent_writepage, &epd, |
2618 | flush_write_bio); | |
ffbd517d | 2619 | flush_epd_write_bio(&epd); |
d1310b2e CM |
2620 | return ret; |
2621 | } | |
d1310b2e CM |
2622 | |
2623 | int extent_readpages(struct extent_io_tree *tree, | |
2624 | struct address_space *mapping, | |
2625 | struct list_head *pages, unsigned nr_pages, | |
2626 | get_extent_t get_extent) | |
2627 | { | |
2628 | struct bio *bio = NULL; | |
2629 | unsigned page_idx; | |
c8b97818 | 2630 | unsigned long bio_flags = 0; |
d1310b2e | 2631 | |
d1310b2e CM |
2632 | for (page_idx = 0; page_idx < nr_pages; page_idx++) { |
2633 | struct page *page = list_entry(pages->prev, struct page, lru); | |
2634 | ||
2635 | prefetchw(&page->flags); | |
2636 | list_del(&page->lru); | |
28ecb609 | 2637 | if (!add_to_page_cache_lru(page, mapping, |
43e817a1 | 2638 | page->index, GFP_NOFS)) { |
f188591e | 2639 | __extent_read_full_page(tree, page, get_extent, |
c8b97818 | 2640 | &bio, 0, &bio_flags); |
d1310b2e CM |
2641 | } |
2642 | page_cache_release(page); | |
2643 | } | |
d1310b2e CM |
2644 | BUG_ON(!list_empty(pages)); |
2645 | if (bio) | |
c8b97818 | 2646 | submit_one_bio(READ, bio, 0, bio_flags); |
d1310b2e CM |
2647 | return 0; |
2648 | } | |
d1310b2e CM |
2649 | |
2650 | /* | |
2651 | * basic invalidatepage code, this waits on any locked or writeback | |
2652 | * ranges corresponding to the page, and then deletes any extent state | |
2653 | * records from the tree | |
2654 | */ | |
2655 | int extent_invalidatepage(struct extent_io_tree *tree, | |
2656 | struct page *page, unsigned long offset) | |
2657 | { | |
2ac55d41 | 2658 | struct extent_state *cached_state = NULL; |
d1310b2e CM |
2659 | u64 start = ((u64)page->index << PAGE_CACHE_SHIFT); |
2660 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
2661 | size_t blocksize = page->mapping->host->i_sb->s_blocksize; | |
2662 | ||
d397712b | 2663 | start += (offset + blocksize - 1) & ~(blocksize - 1); |
d1310b2e CM |
2664 | if (start > end) |
2665 | return 0; | |
2666 | ||
2ac55d41 | 2667 | lock_extent_bits(tree, start, end, 0, &cached_state, GFP_NOFS); |
1edbb734 | 2668 | wait_on_page_writeback(page); |
d1310b2e | 2669 | clear_extent_bit(tree, start, end, |
32c00aff JB |
2670 | EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC | |
2671 | EXTENT_DO_ACCOUNTING, | |
2ac55d41 | 2672 | 1, 1, &cached_state, GFP_NOFS); |
d1310b2e CM |
2673 | return 0; |
2674 | } | |
d1310b2e | 2675 | |
7b13b7b1 CM |
2676 | /* |
2677 | * a helper for releasepage, this tests for areas of the page that | |
2678 | * are locked or under IO and drops the related state bits if it is safe | |
2679 | * to drop the page. | |
2680 | */ | |
2681 | int try_release_extent_state(struct extent_map_tree *map, | |
2682 | struct extent_io_tree *tree, struct page *page, | |
2683 | gfp_t mask) | |
2684 | { | |
2685 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
2686 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
2687 | int ret = 1; | |
2688 | ||
211f90e6 | 2689 | if (test_range_bit(tree, start, end, |
8b62b72b | 2690 | EXTENT_IOBITS, 0, NULL)) |
7b13b7b1 CM |
2691 | ret = 0; |
2692 | else { | |
2693 | if ((mask & GFP_NOFS) == GFP_NOFS) | |
2694 | mask = GFP_NOFS; | |
11ef160f CM |
2695 | /* |
2696 | * at this point we can safely clear everything except the | |
2697 | * locked bit and the nodatasum bit | |
2698 | */ | |
e3f24cc5 | 2699 | ret = clear_extent_bit(tree, start, end, |
11ef160f CM |
2700 | ~(EXTENT_LOCKED | EXTENT_NODATASUM), |
2701 | 0, 0, NULL, mask); | |
e3f24cc5 CM |
2702 | |
2703 | /* if clear_extent_bit failed for enomem reasons, | |
2704 | * we can't allow the release to continue. | |
2705 | */ | |
2706 | if (ret < 0) | |
2707 | ret = 0; | |
2708 | else | |
2709 | ret = 1; | |
7b13b7b1 CM |
2710 | } |
2711 | return ret; | |
2712 | } | |
7b13b7b1 | 2713 | |
d1310b2e CM |
2714 | /* |
2715 | * a helper for releasepage. As long as there are no locked extents | |
2716 | * in the range corresponding to the page, both state records and extent | |
2717 | * map records are removed | |
2718 | */ | |
2719 | int try_release_extent_mapping(struct extent_map_tree *map, | |
70dec807 CM |
2720 | struct extent_io_tree *tree, struct page *page, |
2721 | gfp_t mask) | |
d1310b2e CM |
2722 | { |
2723 | struct extent_map *em; | |
2724 | u64 start = (u64)page->index << PAGE_CACHE_SHIFT; | |
2725 | u64 end = start + PAGE_CACHE_SIZE - 1; | |
7b13b7b1 | 2726 | |
70dec807 CM |
2727 | if ((mask & __GFP_WAIT) && |
2728 | page->mapping->host->i_size > 16 * 1024 * 1024) { | |
39b5637f | 2729 | u64 len; |
70dec807 | 2730 | while (start <= end) { |
39b5637f | 2731 | len = end - start + 1; |
890871be | 2732 | write_lock(&map->lock); |
39b5637f | 2733 | em = lookup_extent_mapping(map, start, len); |
c704005d | 2734 | if (IS_ERR_OR_NULL(em)) { |
890871be | 2735 | write_unlock(&map->lock); |
70dec807 CM |
2736 | break; |
2737 | } | |
7f3c74fb CM |
2738 | if (test_bit(EXTENT_FLAG_PINNED, &em->flags) || |
2739 | em->start != start) { | |
890871be | 2740 | write_unlock(&map->lock); |
70dec807 CM |
2741 | free_extent_map(em); |
2742 | break; | |
2743 | } | |
2744 | if (!test_range_bit(tree, em->start, | |
2745 | extent_map_end(em) - 1, | |
8b62b72b | 2746 | EXTENT_LOCKED | EXTENT_WRITEBACK, |
9655d298 | 2747 | 0, NULL)) { |
70dec807 CM |
2748 | remove_extent_mapping(map, em); |
2749 | /* once for the rb tree */ | |
2750 | free_extent_map(em); | |
2751 | } | |
2752 | start = extent_map_end(em); | |
890871be | 2753 | write_unlock(&map->lock); |
70dec807 CM |
2754 | |
2755 | /* once for us */ | |
d1310b2e CM |
2756 | free_extent_map(em); |
2757 | } | |
d1310b2e | 2758 | } |
7b13b7b1 | 2759 | return try_release_extent_state(map, tree, page, mask); |
d1310b2e | 2760 | } |
d1310b2e | 2761 | |
ec29ed5b CM |
2762 | /* |
2763 | * helper function for fiemap, which doesn't want to see any holes. | |
2764 | * This maps until we find something past 'last' | |
2765 | */ | |
2766 | static struct extent_map *get_extent_skip_holes(struct inode *inode, | |
2767 | u64 offset, | |
2768 | u64 last, | |
2769 | get_extent_t *get_extent) | |
2770 | { | |
2771 | u64 sectorsize = BTRFS_I(inode)->root->sectorsize; | |
2772 | struct extent_map *em; | |
2773 | u64 len; | |
2774 | ||
2775 | if (offset >= last) | |
2776 | return NULL; | |
2777 | ||
2778 | while(1) { | |
2779 | len = last - offset; | |
2780 | if (len == 0) | |
2781 | break; | |
2782 | len = (len + sectorsize - 1) & ~(sectorsize - 1); | |
2783 | em = get_extent(inode, NULL, 0, offset, len, 0); | |
c704005d | 2784 | if (IS_ERR_OR_NULL(em)) |
ec29ed5b CM |
2785 | return em; |
2786 | ||
2787 | /* if this isn't a hole return it */ | |
2788 | if (!test_bit(EXTENT_FLAG_VACANCY, &em->flags) && | |
2789 | em->block_start != EXTENT_MAP_HOLE) { | |
2790 | return em; | |
2791 | } | |
2792 | ||
2793 | /* this is a hole, advance to the next extent */ | |
2794 | offset = extent_map_end(em); | |
2795 | free_extent_map(em); | |
2796 | if (offset >= last) | |
2797 | break; | |
2798 | } | |
2799 | return NULL; | |
2800 | } | |
2801 | ||
1506fcc8 YS |
2802 | int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, |
2803 | __u64 start, __u64 len, get_extent_t *get_extent) | |
2804 | { | |
975f84fe | 2805 | int ret = 0; |
1506fcc8 YS |
2806 | u64 off = start; |
2807 | u64 max = start + len; | |
2808 | u32 flags = 0; | |
975f84fe JB |
2809 | u32 found_type; |
2810 | u64 last; | |
ec29ed5b | 2811 | u64 last_for_get_extent = 0; |
1506fcc8 | 2812 | u64 disko = 0; |
ec29ed5b | 2813 | u64 isize = i_size_read(inode); |
975f84fe | 2814 | struct btrfs_key found_key; |
1506fcc8 | 2815 | struct extent_map *em = NULL; |
2ac55d41 | 2816 | struct extent_state *cached_state = NULL; |
975f84fe JB |
2817 | struct btrfs_path *path; |
2818 | struct btrfs_file_extent_item *item; | |
1506fcc8 | 2819 | int end = 0; |
ec29ed5b CM |
2820 | u64 em_start = 0; |
2821 | u64 em_len = 0; | |
2822 | u64 em_end = 0; | |
1506fcc8 | 2823 | unsigned long emflags; |
1506fcc8 YS |
2824 | |
2825 | if (len == 0) | |
2826 | return -EINVAL; | |
2827 | ||
975f84fe JB |
2828 | path = btrfs_alloc_path(); |
2829 | if (!path) | |
2830 | return -ENOMEM; | |
2831 | path->leave_spinning = 1; | |
2832 | ||
ec29ed5b CM |
2833 | /* |
2834 | * lookup the last file extent. We're not using i_size here | |
2835 | * because there might be preallocation past i_size | |
2836 | */ | |
975f84fe | 2837 | ret = btrfs_lookup_file_extent(NULL, BTRFS_I(inode)->root, |
33345d01 | 2838 | path, btrfs_ino(inode), -1, 0); |
975f84fe JB |
2839 | if (ret < 0) { |
2840 | btrfs_free_path(path); | |
2841 | return ret; | |
2842 | } | |
2843 | WARN_ON(!ret); | |
2844 | path->slots[0]--; | |
2845 | item = btrfs_item_ptr(path->nodes[0], path->slots[0], | |
2846 | struct btrfs_file_extent_item); | |
2847 | btrfs_item_key_to_cpu(path->nodes[0], &found_key, path->slots[0]); | |
2848 | found_type = btrfs_key_type(&found_key); | |
2849 | ||
ec29ed5b | 2850 | /* No extents, but there might be delalloc bits */ |
33345d01 | 2851 | if (found_key.objectid != btrfs_ino(inode) || |
975f84fe | 2852 | found_type != BTRFS_EXTENT_DATA_KEY) { |
ec29ed5b CM |
2853 | /* have to trust i_size as the end */ |
2854 | last = (u64)-1; | |
2855 | last_for_get_extent = isize; | |
2856 | } else { | |
2857 | /* | |
2858 | * remember the start of the last extent. There are a | |
2859 | * bunch of different factors that go into the length of the | |
2860 | * extent, so its much less complex to remember where it started | |
2861 | */ | |
2862 | last = found_key.offset; | |
2863 | last_for_get_extent = last + 1; | |
975f84fe | 2864 | } |
975f84fe JB |
2865 | btrfs_free_path(path); |
2866 | ||
ec29ed5b CM |
2867 | /* |
2868 | * we might have some extents allocated but more delalloc past those | |
2869 | * extents. so, we trust isize unless the start of the last extent is | |
2870 | * beyond isize | |
2871 | */ | |
2872 | if (last < isize) { | |
2873 | last = (u64)-1; | |
2874 | last_for_get_extent = isize; | |
2875 | } | |
2876 | ||
2ac55d41 JB |
2877 | lock_extent_bits(&BTRFS_I(inode)->io_tree, start, start + len, 0, |
2878 | &cached_state, GFP_NOFS); | |
ec29ed5b CM |
2879 | |
2880 | em = get_extent_skip_holes(inode, off, last_for_get_extent, | |
2881 | get_extent); | |
1506fcc8 YS |
2882 | if (!em) |
2883 | goto out; | |
2884 | if (IS_ERR(em)) { | |
2885 | ret = PTR_ERR(em); | |
2886 | goto out; | |
2887 | } | |
975f84fe | 2888 | |
1506fcc8 | 2889 | while (!end) { |
ea8efc74 CM |
2890 | u64 offset_in_extent; |
2891 | ||
2892 | /* break if the extent we found is outside the range */ | |
2893 | if (em->start >= max || extent_map_end(em) < off) | |
2894 | break; | |
2895 | ||
2896 | /* | |
2897 | * get_extent may return an extent that starts before our | |
2898 | * requested range. We have to make sure the ranges | |
2899 | * we return to fiemap always move forward and don't | |
2900 | * overlap, so adjust the offsets here | |
2901 | */ | |
2902 | em_start = max(em->start, off); | |
1506fcc8 | 2903 | |
ea8efc74 CM |
2904 | /* |
2905 | * record the offset from the start of the extent | |
2906 | * for adjusting the disk offset below | |
2907 | */ | |
2908 | offset_in_extent = em_start - em->start; | |
ec29ed5b | 2909 | em_end = extent_map_end(em); |
ea8efc74 | 2910 | em_len = em_end - em_start; |
ec29ed5b | 2911 | emflags = em->flags; |
1506fcc8 YS |
2912 | disko = 0; |
2913 | flags = 0; | |
2914 | ||
ea8efc74 CM |
2915 | /* |
2916 | * bump off for our next call to get_extent | |
2917 | */ | |
2918 | off = extent_map_end(em); | |
2919 | if (off >= max) | |
2920 | end = 1; | |
2921 | ||
93dbfad7 | 2922 | if (em->block_start == EXTENT_MAP_LAST_BYTE) { |
1506fcc8 YS |
2923 | end = 1; |
2924 | flags |= FIEMAP_EXTENT_LAST; | |
93dbfad7 | 2925 | } else if (em->block_start == EXTENT_MAP_INLINE) { |
1506fcc8 YS |
2926 | flags |= (FIEMAP_EXTENT_DATA_INLINE | |
2927 | FIEMAP_EXTENT_NOT_ALIGNED); | |
93dbfad7 | 2928 | } else if (em->block_start == EXTENT_MAP_DELALLOC) { |
1506fcc8 YS |
2929 | flags |= (FIEMAP_EXTENT_DELALLOC | |
2930 | FIEMAP_EXTENT_UNKNOWN); | |
93dbfad7 | 2931 | } else { |
ea8efc74 | 2932 | disko = em->block_start + offset_in_extent; |
1506fcc8 YS |
2933 | } |
2934 | if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) | |
2935 | flags |= FIEMAP_EXTENT_ENCODED; | |
2936 | ||
1506fcc8 YS |
2937 | free_extent_map(em); |
2938 | em = NULL; | |
ec29ed5b CM |
2939 | if ((em_start >= last) || em_len == (u64)-1 || |
2940 | (last == (u64)-1 && isize <= em_end)) { | |
1506fcc8 YS |
2941 | flags |= FIEMAP_EXTENT_LAST; |
2942 | end = 1; | |
2943 | } | |
2944 | ||
ec29ed5b CM |
2945 | /* now scan forward to see if this is really the last extent. */ |
2946 | em = get_extent_skip_holes(inode, off, last_for_get_extent, | |
2947 | get_extent); | |
2948 | if (IS_ERR(em)) { | |
2949 | ret = PTR_ERR(em); | |
2950 | goto out; | |
2951 | } | |
2952 | if (!em) { | |
975f84fe JB |
2953 | flags |= FIEMAP_EXTENT_LAST; |
2954 | end = 1; | |
2955 | } | |
ec29ed5b CM |
2956 | ret = fiemap_fill_next_extent(fieinfo, em_start, disko, |
2957 | em_len, flags); | |
2958 | if (ret) | |
2959 | goto out_free; | |
1506fcc8 YS |
2960 | } |
2961 | out_free: | |
2962 | free_extent_map(em); | |
2963 | out: | |
2ac55d41 JB |
2964 | unlock_extent_cached(&BTRFS_I(inode)->io_tree, start, start + len, |
2965 | &cached_state, GFP_NOFS); | |
1506fcc8 YS |
2966 | return ret; |
2967 | } | |
2968 | ||
d1310b2e CM |
2969 | static inline struct page *extent_buffer_page(struct extent_buffer *eb, |
2970 | unsigned long i) | |
2971 | { | |
2972 | struct page *p; | |
2973 | struct address_space *mapping; | |
2974 | ||
2975 | if (i == 0) | |
2976 | return eb->first_page; | |
2977 | i += eb->start >> PAGE_CACHE_SHIFT; | |
2978 | mapping = eb->first_page->mapping; | |
33958dc6 CM |
2979 | if (!mapping) |
2980 | return NULL; | |
0ee0fda0 SW |
2981 | |
2982 | /* | |
2983 | * extent_buffer_page is only called after pinning the page | |
2984 | * by increasing the reference count. So we know the page must | |
2985 | * be in the radix tree. | |
2986 | */ | |
0ee0fda0 | 2987 | rcu_read_lock(); |
d1310b2e | 2988 | p = radix_tree_lookup(&mapping->page_tree, i); |
0ee0fda0 | 2989 | rcu_read_unlock(); |
2b1f55b0 | 2990 | |
d1310b2e CM |
2991 | return p; |
2992 | } | |
2993 | ||
6af118ce | 2994 | static inline unsigned long num_extent_pages(u64 start, u64 len) |
728131d8 | 2995 | { |
6af118ce CM |
2996 | return ((start + len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT) - |
2997 | (start >> PAGE_CACHE_SHIFT); | |
728131d8 CM |
2998 | } |
2999 | ||
d1310b2e CM |
3000 | static struct extent_buffer *__alloc_extent_buffer(struct extent_io_tree *tree, |
3001 | u64 start, | |
3002 | unsigned long len, | |
3003 | gfp_t mask) | |
3004 | { | |
3005 | struct extent_buffer *eb = NULL; | |
3935127c | 3006 | #if LEAK_DEBUG |
2d2ae547 | 3007 | unsigned long flags; |
4bef0848 | 3008 | #endif |
d1310b2e | 3009 | |
d1310b2e | 3010 | eb = kmem_cache_zalloc(extent_buffer_cache, mask); |
91ca338d TI |
3011 | if (eb == NULL) |
3012 | return NULL; | |
d1310b2e CM |
3013 | eb->start = start; |
3014 | eb->len = len; | |
b4ce94de CM |
3015 | spin_lock_init(&eb->lock); |
3016 | init_waitqueue_head(&eb->lock_wq); | |
3017 | ||
3935127c | 3018 | #if LEAK_DEBUG |
2d2ae547 CM |
3019 | spin_lock_irqsave(&leak_lock, flags); |
3020 | list_add(&eb->leak_list, &buffers); | |
3021 | spin_unlock_irqrestore(&leak_lock, flags); | |
4bef0848 | 3022 | #endif |
d1310b2e CM |
3023 | atomic_set(&eb->refs, 1); |
3024 | ||
3025 | return eb; | |
3026 | } | |
3027 | ||
3028 | static void __free_extent_buffer(struct extent_buffer *eb) | |
3029 | { | |
3935127c | 3030 | #if LEAK_DEBUG |
2d2ae547 CM |
3031 | unsigned long flags; |
3032 | spin_lock_irqsave(&leak_lock, flags); | |
3033 | list_del(&eb->leak_list); | |
3034 | spin_unlock_irqrestore(&leak_lock, flags); | |
4bef0848 | 3035 | #endif |
d1310b2e CM |
3036 | kmem_cache_free(extent_buffer_cache, eb); |
3037 | } | |
3038 | ||
897ca6e9 MX |
3039 | /* |
3040 | * Helper for releasing extent buffer page. | |
3041 | */ | |
3042 | static void btrfs_release_extent_buffer_page(struct extent_buffer *eb, | |
3043 | unsigned long start_idx) | |
3044 | { | |
3045 | unsigned long index; | |
3046 | struct page *page; | |
3047 | ||
3048 | if (!eb->first_page) | |
3049 | return; | |
3050 | ||
3051 | index = num_extent_pages(eb->start, eb->len); | |
3052 | if (start_idx >= index) | |
3053 | return; | |
3054 | ||
3055 | do { | |
3056 | index--; | |
3057 | page = extent_buffer_page(eb, index); | |
3058 | if (page) | |
3059 | page_cache_release(page); | |
3060 | } while (index != start_idx); | |
3061 | } | |
3062 | ||
3063 | /* | |
3064 | * Helper for releasing the extent buffer. | |
3065 | */ | |
3066 | static inline void btrfs_release_extent_buffer(struct extent_buffer *eb) | |
3067 | { | |
3068 | btrfs_release_extent_buffer_page(eb, 0); | |
3069 | __free_extent_buffer(eb); | |
3070 | } | |
3071 | ||
d1310b2e CM |
3072 | struct extent_buffer *alloc_extent_buffer(struct extent_io_tree *tree, |
3073 | u64 start, unsigned long len, | |
ba144192 | 3074 | struct page *page0) |
d1310b2e CM |
3075 | { |
3076 | unsigned long num_pages = num_extent_pages(start, len); | |
3077 | unsigned long i; | |
3078 | unsigned long index = start >> PAGE_CACHE_SHIFT; | |
3079 | struct extent_buffer *eb; | |
6af118ce | 3080 | struct extent_buffer *exists = NULL; |
d1310b2e CM |
3081 | struct page *p; |
3082 | struct address_space *mapping = tree->mapping; | |
3083 | int uptodate = 1; | |
19fe0a8b | 3084 | int ret; |
d1310b2e | 3085 | |
19fe0a8b MX |
3086 | rcu_read_lock(); |
3087 | eb = radix_tree_lookup(&tree->buffer, start >> PAGE_CACHE_SHIFT); | |
3088 | if (eb && atomic_inc_not_zero(&eb->refs)) { | |
3089 | rcu_read_unlock(); | |
0f9dd46c | 3090 | mark_page_accessed(eb->first_page); |
6af118ce CM |
3091 | return eb; |
3092 | } | |
19fe0a8b | 3093 | rcu_read_unlock(); |
6af118ce | 3094 | |
ba144192 | 3095 | eb = __alloc_extent_buffer(tree, start, len, GFP_NOFS); |
2b114d1d | 3096 | if (!eb) |
d1310b2e CM |
3097 | return NULL; |
3098 | ||
d1310b2e CM |
3099 | if (page0) { |
3100 | eb->first_page = page0; | |
3101 | i = 1; | |
3102 | index++; | |
3103 | page_cache_get(page0); | |
3104 | mark_page_accessed(page0); | |
3105 | set_page_extent_mapped(page0); | |
d1310b2e | 3106 | set_page_extent_head(page0, len); |
f188591e | 3107 | uptodate = PageUptodate(page0); |
d1310b2e CM |
3108 | } else { |
3109 | i = 0; | |
3110 | } | |
3111 | for (; i < num_pages; i++, index++) { | |
ba144192 | 3112 | p = find_or_create_page(mapping, index, GFP_NOFS | __GFP_HIGHMEM); |
d1310b2e CM |
3113 | if (!p) { |
3114 | WARN_ON(1); | |
6af118ce | 3115 | goto free_eb; |
d1310b2e CM |
3116 | } |
3117 | set_page_extent_mapped(p); | |
3118 | mark_page_accessed(p); | |
3119 | if (i == 0) { | |
3120 | eb->first_page = p; | |
3121 | set_page_extent_head(p, len); | |
3122 | } else { | |
3123 | set_page_private(p, EXTENT_PAGE_PRIVATE); | |
3124 | } | |
3125 | if (!PageUptodate(p)) | |
3126 | uptodate = 0; | |
eb14ab8e CM |
3127 | |
3128 | /* | |
3129 | * see below about how we avoid a nasty race with release page | |
3130 | * and why we unlock later | |
3131 | */ | |
3132 | if (i != 0) | |
3133 | unlock_page(p); | |
d1310b2e CM |
3134 | } |
3135 | if (uptodate) | |
b4ce94de | 3136 | set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags); |
d1310b2e | 3137 | |
19fe0a8b MX |
3138 | ret = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM); |
3139 | if (ret) | |
3140 | goto free_eb; | |
3141 | ||
6af118ce | 3142 | spin_lock(&tree->buffer_lock); |
19fe0a8b MX |
3143 | ret = radix_tree_insert(&tree->buffer, start >> PAGE_CACHE_SHIFT, eb); |
3144 | if (ret == -EEXIST) { | |
3145 | exists = radix_tree_lookup(&tree->buffer, | |
3146 | start >> PAGE_CACHE_SHIFT); | |
6af118ce CM |
3147 | /* add one reference for the caller */ |
3148 | atomic_inc(&exists->refs); | |
3149 | spin_unlock(&tree->buffer_lock); | |
19fe0a8b | 3150 | radix_tree_preload_end(); |
6af118ce CM |
3151 | goto free_eb; |
3152 | } | |
6af118ce CM |
3153 | /* add one reference for the tree */ |
3154 | atomic_inc(&eb->refs); | |
f044ba78 | 3155 | spin_unlock(&tree->buffer_lock); |
19fe0a8b | 3156 | radix_tree_preload_end(); |
eb14ab8e CM |
3157 | |
3158 | /* | |
3159 | * there is a race where release page may have | |
3160 | * tried to find this extent buffer in the radix | |
3161 | * but failed. It will tell the VM it is safe to | |
3162 | * reclaim the, and it will clear the page private bit. | |
3163 | * We must make sure to set the page private bit properly | |
3164 | * after the extent buffer is in the radix tree so | |
3165 | * it doesn't get lost | |
3166 | */ | |
3167 | set_page_extent_mapped(eb->first_page); | |
3168 | set_page_extent_head(eb->first_page, eb->len); | |
3169 | if (!page0) | |
3170 | unlock_page(eb->first_page); | |
d1310b2e CM |
3171 | return eb; |
3172 | ||
6af118ce | 3173 | free_eb: |
eb14ab8e CM |
3174 | if (eb->first_page && !page0) |
3175 | unlock_page(eb->first_page); | |
3176 | ||
d1310b2e | 3177 | if (!atomic_dec_and_test(&eb->refs)) |
6af118ce | 3178 | return exists; |
897ca6e9 | 3179 | btrfs_release_extent_buffer(eb); |
6af118ce | 3180 | return exists; |
d1310b2e | 3181 | } |
d1310b2e CM |
3182 | |
3183 | struct extent_buffer *find_extent_buffer(struct extent_io_tree *tree, | |
f09d1f60 | 3184 | u64 start, unsigned long len) |
d1310b2e | 3185 | { |
d1310b2e | 3186 | struct extent_buffer *eb; |
d1310b2e | 3187 | |
19fe0a8b MX |
3188 | rcu_read_lock(); |
3189 | eb = radix_tree_lookup(&tree->buffer, start >> PAGE_CACHE_SHIFT); | |
3190 | if (eb && atomic_inc_not_zero(&eb->refs)) { | |
3191 | rcu_read_unlock(); | |
0f9dd46c | 3192 | mark_page_accessed(eb->first_page); |
19fe0a8b MX |
3193 | return eb; |
3194 | } | |
3195 | rcu_read_unlock(); | |
0f9dd46c | 3196 | |
19fe0a8b | 3197 | return NULL; |
d1310b2e | 3198 | } |
d1310b2e CM |
3199 | |
3200 | void free_extent_buffer(struct extent_buffer *eb) | |
3201 | { | |
d1310b2e CM |
3202 | if (!eb) |
3203 | return; | |
3204 | ||
3205 | if (!atomic_dec_and_test(&eb->refs)) | |
3206 | return; | |
3207 | ||
6af118ce | 3208 | WARN_ON(1); |
d1310b2e | 3209 | } |
d1310b2e CM |
3210 | |
3211 | int clear_extent_buffer_dirty(struct extent_io_tree *tree, | |
3212 | struct extent_buffer *eb) | |
3213 | { | |
d1310b2e CM |
3214 | unsigned long i; |
3215 | unsigned long num_pages; | |
3216 | struct page *page; | |
3217 | ||
d1310b2e CM |
3218 | num_pages = num_extent_pages(eb->start, eb->len); |
3219 | ||
3220 | for (i = 0; i < num_pages; i++) { | |
3221 | page = extent_buffer_page(eb, i); | |
b9473439 | 3222 | if (!PageDirty(page)) |
d2c3f4f6 CM |
3223 | continue; |
3224 | ||
a61e6f29 | 3225 | lock_page(page); |
eb14ab8e CM |
3226 | WARN_ON(!PagePrivate(page)); |
3227 | ||
3228 | set_page_extent_mapped(page); | |
d1310b2e CM |
3229 | if (i == 0) |
3230 | set_page_extent_head(page, eb->len); | |
d1310b2e | 3231 | |
d1310b2e | 3232 | clear_page_dirty_for_io(page); |
0ee0fda0 | 3233 | spin_lock_irq(&page->mapping->tree_lock); |
d1310b2e CM |
3234 | if (!PageDirty(page)) { |
3235 | radix_tree_tag_clear(&page->mapping->page_tree, | |
3236 | page_index(page), | |
3237 | PAGECACHE_TAG_DIRTY); | |
3238 | } | |
0ee0fda0 | 3239 | spin_unlock_irq(&page->mapping->tree_lock); |
a61e6f29 | 3240 | unlock_page(page); |
d1310b2e CM |
3241 | } |
3242 | return 0; | |
3243 | } | |
d1310b2e | 3244 | |
d1310b2e CM |
3245 | int set_extent_buffer_dirty(struct extent_io_tree *tree, |
3246 | struct extent_buffer *eb) | |
3247 | { | |
3248 | unsigned long i; | |
3249 | unsigned long num_pages; | |
b9473439 | 3250 | int was_dirty = 0; |
d1310b2e | 3251 | |
b9473439 | 3252 | was_dirty = test_and_set_bit(EXTENT_BUFFER_DIRTY, &eb->bflags); |
d1310b2e | 3253 | num_pages = num_extent_pages(eb->start, eb->len); |
b9473439 | 3254 | for (i = 0; i < num_pages; i++) |
d1310b2e | 3255 | __set_page_dirty_nobuffers(extent_buffer_page(eb, i)); |
b9473439 | 3256 | return was_dirty; |
d1310b2e | 3257 | } |
d1310b2e | 3258 | |
1259ab75 | 3259 | int clear_extent_buffer_uptodate(struct extent_io_tree *tree, |
2ac55d41 JB |
3260 | struct extent_buffer *eb, |
3261 | struct extent_state **cached_state) | |
1259ab75 CM |
3262 | { |
3263 | unsigned long i; | |
3264 | struct page *page; | |
3265 | unsigned long num_pages; | |
3266 | ||
3267 | num_pages = num_extent_pages(eb->start, eb->len); | |
b4ce94de | 3268 | clear_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags); |
1259ab75 CM |
3269 | |
3270 | clear_extent_uptodate(tree, eb->start, eb->start + eb->len - 1, | |
2ac55d41 | 3271 | cached_state, GFP_NOFS); |
1259ab75 CM |
3272 | for (i = 0; i < num_pages; i++) { |
3273 | page = extent_buffer_page(eb, i); | |
33958dc6 CM |
3274 | if (page) |
3275 | ClearPageUptodate(page); | |
1259ab75 CM |
3276 | } |
3277 | return 0; | |
3278 | } | |
3279 | ||
d1310b2e CM |
3280 | int set_extent_buffer_uptodate(struct extent_io_tree *tree, |
3281 | struct extent_buffer *eb) | |
3282 | { | |
3283 | unsigned long i; | |
3284 | struct page *page; | |
3285 | unsigned long num_pages; | |
3286 | ||
3287 | num_pages = num_extent_pages(eb->start, eb->len); | |
3288 | ||
3289 | set_extent_uptodate(tree, eb->start, eb->start + eb->len - 1, | |
507903b8 | 3290 | NULL, GFP_NOFS); |
d1310b2e CM |
3291 | for (i = 0; i < num_pages; i++) { |
3292 | page = extent_buffer_page(eb, i); | |
3293 | if ((i == 0 && (eb->start & (PAGE_CACHE_SIZE - 1))) || | |
3294 | ((i == num_pages - 1) && | |
3295 | ((eb->start + eb->len) & (PAGE_CACHE_SIZE - 1)))) { | |
3296 | check_page_uptodate(tree, page); | |
3297 | continue; | |
3298 | } | |
3299 | SetPageUptodate(page); | |
3300 | } | |
3301 | return 0; | |
3302 | } | |
d1310b2e | 3303 | |
ce9adaa5 CM |
3304 | int extent_range_uptodate(struct extent_io_tree *tree, |
3305 | u64 start, u64 end) | |
3306 | { | |
3307 | struct page *page; | |
3308 | int ret; | |
3309 | int pg_uptodate = 1; | |
3310 | int uptodate; | |
3311 | unsigned long index; | |
3312 | ||
9655d298 | 3313 | ret = test_range_bit(tree, start, end, EXTENT_UPTODATE, 1, NULL); |
ce9adaa5 CM |
3314 | if (ret) |
3315 | return 1; | |
d397712b | 3316 | while (start <= end) { |
ce9adaa5 CM |
3317 | index = start >> PAGE_CACHE_SHIFT; |
3318 | page = find_get_page(tree->mapping, index); | |
3319 | uptodate = PageUptodate(page); | |
3320 | page_cache_release(page); | |
3321 | if (!uptodate) { | |
3322 | pg_uptodate = 0; | |
3323 | break; | |
3324 | } | |
3325 | start += PAGE_CACHE_SIZE; | |
3326 | } | |
3327 | return pg_uptodate; | |
3328 | } | |
3329 | ||
d1310b2e | 3330 | int extent_buffer_uptodate(struct extent_io_tree *tree, |
2ac55d41 JB |
3331 | struct extent_buffer *eb, |
3332 | struct extent_state *cached_state) | |
d1310b2e | 3333 | { |
728131d8 | 3334 | int ret = 0; |
ce9adaa5 CM |
3335 | unsigned long num_pages; |
3336 | unsigned long i; | |
728131d8 CM |
3337 | struct page *page; |
3338 | int pg_uptodate = 1; | |
3339 | ||
b4ce94de | 3340 | if (test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags)) |
4235298e | 3341 | return 1; |
728131d8 | 3342 | |
4235298e | 3343 | ret = test_range_bit(tree, eb->start, eb->start + eb->len - 1, |
2ac55d41 | 3344 | EXTENT_UPTODATE, 1, cached_state); |
4235298e CM |
3345 | if (ret) |
3346 | return ret; | |
728131d8 CM |
3347 | |
3348 | num_pages = num_extent_pages(eb->start, eb->len); | |
3349 | for (i = 0; i < num_pages; i++) { | |
3350 | page = extent_buffer_page(eb, i); | |
3351 | if (!PageUptodate(page)) { | |
3352 | pg_uptodate = 0; | |
3353 | break; | |
3354 | } | |
3355 | } | |
4235298e | 3356 | return pg_uptodate; |
d1310b2e | 3357 | } |
d1310b2e CM |
3358 | |
3359 | int read_extent_buffer_pages(struct extent_io_tree *tree, | |
3360 | struct extent_buffer *eb, | |
a86c12c7 | 3361 | u64 start, int wait, |
f188591e | 3362 | get_extent_t *get_extent, int mirror_num) |
d1310b2e CM |
3363 | { |
3364 | unsigned long i; | |
3365 | unsigned long start_i; | |
3366 | struct page *page; | |
3367 | int err; | |
3368 | int ret = 0; | |
ce9adaa5 CM |
3369 | int locked_pages = 0; |
3370 | int all_uptodate = 1; | |
3371 | int inc_all_pages = 0; | |
d1310b2e | 3372 | unsigned long num_pages; |
a86c12c7 | 3373 | struct bio *bio = NULL; |
c8b97818 | 3374 | unsigned long bio_flags = 0; |
a86c12c7 | 3375 | |
b4ce94de | 3376 | if (test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags)) |
d1310b2e CM |
3377 | return 0; |
3378 | ||
ce9adaa5 | 3379 | if (test_range_bit(tree, eb->start, eb->start + eb->len - 1, |
9655d298 | 3380 | EXTENT_UPTODATE, 1, NULL)) { |
d1310b2e CM |
3381 | return 0; |
3382 | } | |
3383 | ||
3384 | if (start) { | |
3385 | WARN_ON(start < eb->start); | |
3386 | start_i = (start >> PAGE_CACHE_SHIFT) - | |
3387 | (eb->start >> PAGE_CACHE_SHIFT); | |
3388 | } else { | |
3389 | start_i = 0; | |
3390 | } | |
3391 | ||
3392 | num_pages = num_extent_pages(eb->start, eb->len); | |
3393 | for (i = start_i; i < num_pages; i++) { | |
3394 | page = extent_buffer_page(eb, i); | |
d1310b2e | 3395 | if (!wait) { |
2db04966 | 3396 | if (!trylock_page(page)) |
ce9adaa5 | 3397 | goto unlock_exit; |
d1310b2e CM |
3398 | } else { |
3399 | lock_page(page); | |
3400 | } | |
ce9adaa5 | 3401 | locked_pages++; |
d397712b | 3402 | if (!PageUptodate(page)) |
ce9adaa5 | 3403 | all_uptodate = 0; |
ce9adaa5 CM |
3404 | } |
3405 | if (all_uptodate) { | |
3406 | if (start_i == 0) | |
b4ce94de | 3407 | set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags); |
ce9adaa5 CM |
3408 | goto unlock_exit; |
3409 | } | |
3410 | ||
3411 | for (i = start_i; i < num_pages; i++) { | |
3412 | page = extent_buffer_page(eb, i); | |
eb14ab8e CM |
3413 | |
3414 | WARN_ON(!PagePrivate(page)); | |
3415 | ||
3416 | set_page_extent_mapped(page); | |
3417 | if (i == 0) | |
3418 | set_page_extent_head(page, eb->len); | |
3419 | ||
ce9adaa5 CM |
3420 | if (inc_all_pages) |
3421 | page_cache_get(page); | |
3422 | if (!PageUptodate(page)) { | |
3423 | if (start_i == 0) | |
3424 | inc_all_pages = 1; | |
f188591e | 3425 | ClearPageError(page); |
a86c12c7 | 3426 | err = __extent_read_full_page(tree, page, |
f188591e | 3427 | get_extent, &bio, |
c8b97818 | 3428 | mirror_num, &bio_flags); |
d397712b | 3429 | if (err) |
d1310b2e | 3430 | ret = err; |
d1310b2e CM |
3431 | } else { |
3432 | unlock_page(page); | |
3433 | } | |
3434 | } | |
3435 | ||
a86c12c7 | 3436 | if (bio) |
c8b97818 | 3437 | submit_one_bio(READ, bio, mirror_num, bio_flags); |
a86c12c7 | 3438 | |
d397712b | 3439 | if (ret || !wait) |
d1310b2e | 3440 | return ret; |
d397712b | 3441 | |
d1310b2e CM |
3442 | for (i = start_i; i < num_pages; i++) { |
3443 | page = extent_buffer_page(eb, i); | |
3444 | wait_on_page_locked(page); | |
d397712b | 3445 | if (!PageUptodate(page)) |
d1310b2e | 3446 | ret = -EIO; |
d1310b2e | 3447 | } |
d397712b | 3448 | |
d1310b2e | 3449 | if (!ret) |
b4ce94de | 3450 | set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags); |
d1310b2e | 3451 | return ret; |
ce9adaa5 CM |
3452 | |
3453 | unlock_exit: | |
3454 | i = start_i; | |
d397712b | 3455 | while (locked_pages > 0) { |
ce9adaa5 CM |
3456 | page = extent_buffer_page(eb, i); |
3457 | i++; | |
3458 | unlock_page(page); | |
3459 | locked_pages--; | |
3460 | } | |
3461 | return ret; | |
d1310b2e | 3462 | } |
d1310b2e CM |
3463 | |
3464 | void read_extent_buffer(struct extent_buffer *eb, void *dstv, | |
3465 | unsigned long start, | |
3466 | unsigned long len) | |
3467 | { | |
3468 | size_t cur; | |
3469 | size_t offset; | |
3470 | struct page *page; | |
3471 | char *kaddr; | |
3472 | char *dst = (char *)dstv; | |
3473 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3474 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
d1310b2e CM |
3475 | |
3476 | WARN_ON(start > eb->len); | |
3477 | WARN_ON(start + len > eb->start + eb->len); | |
3478 | ||
3479 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3480 | ||
d397712b | 3481 | while (len > 0) { |
d1310b2e | 3482 | page = extent_buffer_page(eb, i); |
d1310b2e CM |
3483 | |
3484 | cur = min(len, (PAGE_CACHE_SIZE - offset)); | |
3485 | kaddr = kmap_atomic(page, KM_USER1); | |
3486 | memcpy(dst, kaddr + offset, cur); | |
3487 | kunmap_atomic(kaddr, KM_USER1); | |
3488 | ||
3489 | dst += cur; | |
3490 | len -= cur; | |
3491 | offset = 0; | |
3492 | i++; | |
3493 | } | |
3494 | } | |
d1310b2e CM |
3495 | |
3496 | int map_private_extent_buffer(struct extent_buffer *eb, unsigned long start, | |
3497 | unsigned long min_len, char **token, char **map, | |
3498 | unsigned long *map_start, | |
3499 | unsigned long *map_len, int km) | |
3500 | { | |
3501 | size_t offset = start & (PAGE_CACHE_SIZE - 1); | |
3502 | char *kaddr; | |
3503 | struct page *p; | |
3504 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3505 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
3506 | unsigned long end_i = (start_offset + start + min_len - 1) >> | |
3507 | PAGE_CACHE_SHIFT; | |
3508 | ||
3509 | if (i != end_i) | |
3510 | return -EINVAL; | |
3511 | ||
3512 | if (i == 0) { | |
3513 | offset = start_offset; | |
3514 | *map_start = 0; | |
3515 | } else { | |
3516 | offset = 0; | |
3517 | *map_start = ((u64)i << PAGE_CACHE_SHIFT) - start_offset; | |
3518 | } | |
d397712b | 3519 | |
d1310b2e | 3520 | if (start + min_len > eb->len) { |
d397712b CM |
3521 | printk(KERN_ERR "btrfs bad mapping eb start %llu len %lu, " |
3522 | "wanted %lu %lu\n", (unsigned long long)eb->start, | |
3523 | eb->len, start, min_len); | |
d1310b2e | 3524 | WARN_ON(1); |
85026533 | 3525 | return -EINVAL; |
d1310b2e CM |
3526 | } |
3527 | ||
3528 | p = extent_buffer_page(eb, i); | |
d1310b2e CM |
3529 | kaddr = kmap_atomic(p, km); |
3530 | *token = kaddr; | |
3531 | *map = kaddr + offset; | |
3532 | *map_len = PAGE_CACHE_SIZE - offset; | |
3533 | return 0; | |
3534 | } | |
d1310b2e CM |
3535 | |
3536 | int map_extent_buffer(struct extent_buffer *eb, unsigned long start, | |
3537 | unsigned long min_len, | |
3538 | char **token, char **map, | |
3539 | unsigned long *map_start, | |
3540 | unsigned long *map_len, int km) | |
3541 | { | |
3542 | int err; | |
3543 | int save = 0; | |
3544 | if (eb->map_token) { | |
3545 | unmap_extent_buffer(eb, eb->map_token, km); | |
3546 | eb->map_token = NULL; | |
3547 | save = 1; | |
3548 | } | |
3549 | err = map_private_extent_buffer(eb, start, min_len, token, map, | |
3550 | map_start, map_len, km); | |
3551 | if (!err && save) { | |
3552 | eb->map_token = *token; | |
3553 | eb->kaddr = *map; | |
3554 | eb->map_start = *map_start; | |
3555 | eb->map_len = *map_len; | |
3556 | } | |
3557 | return err; | |
3558 | } | |
d1310b2e CM |
3559 | |
3560 | void unmap_extent_buffer(struct extent_buffer *eb, char *token, int km) | |
3561 | { | |
3562 | kunmap_atomic(token, km); | |
3563 | } | |
d1310b2e CM |
3564 | |
3565 | int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv, | |
3566 | unsigned long start, | |
3567 | unsigned long len) | |
3568 | { | |
3569 | size_t cur; | |
3570 | size_t offset; | |
3571 | struct page *page; | |
3572 | char *kaddr; | |
3573 | char *ptr = (char *)ptrv; | |
3574 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3575 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
3576 | int ret = 0; | |
3577 | ||
3578 | WARN_ON(start > eb->len); | |
3579 | WARN_ON(start + len > eb->start + eb->len); | |
3580 | ||
3581 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3582 | ||
d397712b | 3583 | while (len > 0) { |
d1310b2e | 3584 | page = extent_buffer_page(eb, i); |
d1310b2e CM |
3585 | |
3586 | cur = min(len, (PAGE_CACHE_SIZE - offset)); | |
3587 | ||
3588 | kaddr = kmap_atomic(page, KM_USER0); | |
3589 | ret = memcmp(ptr, kaddr + offset, cur); | |
3590 | kunmap_atomic(kaddr, KM_USER0); | |
3591 | if (ret) | |
3592 | break; | |
3593 | ||
3594 | ptr += cur; | |
3595 | len -= cur; | |
3596 | offset = 0; | |
3597 | i++; | |
3598 | } | |
3599 | return ret; | |
3600 | } | |
d1310b2e CM |
3601 | |
3602 | void write_extent_buffer(struct extent_buffer *eb, const void *srcv, | |
3603 | unsigned long start, unsigned long len) | |
3604 | { | |
3605 | size_t cur; | |
3606 | size_t offset; | |
3607 | struct page *page; | |
3608 | char *kaddr; | |
3609 | char *src = (char *)srcv; | |
3610 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3611 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
3612 | ||
3613 | WARN_ON(start > eb->len); | |
3614 | WARN_ON(start + len > eb->start + eb->len); | |
3615 | ||
3616 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3617 | ||
d397712b | 3618 | while (len > 0) { |
d1310b2e CM |
3619 | page = extent_buffer_page(eb, i); |
3620 | WARN_ON(!PageUptodate(page)); | |
3621 | ||
3622 | cur = min(len, PAGE_CACHE_SIZE - offset); | |
3623 | kaddr = kmap_atomic(page, KM_USER1); | |
3624 | memcpy(kaddr + offset, src, cur); | |
3625 | kunmap_atomic(kaddr, KM_USER1); | |
3626 | ||
3627 | src += cur; | |
3628 | len -= cur; | |
3629 | offset = 0; | |
3630 | i++; | |
3631 | } | |
3632 | } | |
d1310b2e CM |
3633 | |
3634 | void memset_extent_buffer(struct extent_buffer *eb, char c, | |
3635 | unsigned long start, unsigned long len) | |
3636 | { | |
3637 | size_t cur; | |
3638 | size_t offset; | |
3639 | struct page *page; | |
3640 | char *kaddr; | |
3641 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3642 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; | |
3643 | ||
3644 | WARN_ON(start > eb->len); | |
3645 | WARN_ON(start + len > eb->start + eb->len); | |
3646 | ||
3647 | offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3648 | ||
d397712b | 3649 | while (len > 0) { |
d1310b2e CM |
3650 | page = extent_buffer_page(eb, i); |
3651 | WARN_ON(!PageUptodate(page)); | |
3652 | ||
3653 | cur = min(len, PAGE_CACHE_SIZE - offset); | |
3654 | kaddr = kmap_atomic(page, KM_USER0); | |
3655 | memset(kaddr + offset, c, cur); | |
3656 | kunmap_atomic(kaddr, KM_USER0); | |
3657 | ||
3658 | len -= cur; | |
3659 | offset = 0; | |
3660 | i++; | |
3661 | } | |
3662 | } | |
d1310b2e CM |
3663 | |
3664 | void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src, | |
3665 | unsigned long dst_offset, unsigned long src_offset, | |
3666 | unsigned long len) | |
3667 | { | |
3668 | u64 dst_len = dst->len; | |
3669 | size_t cur; | |
3670 | size_t offset; | |
3671 | struct page *page; | |
3672 | char *kaddr; | |
3673 | size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3674 | unsigned long i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT; | |
3675 | ||
3676 | WARN_ON(src->len != dst_len); | |
3677 | ||
3678 | offset = (start_offset + dst_offset) & | |
3679 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3680 | ||
d397712b | 3681 | while (len > 0) { |
d1310b2e CM |
3682 | page = extent_buffer_page(dst, i); |
3683 | WARN_ON(!PageUptodate(page)); | |
3684 | ||
3685 | cur = min(len, (unsigned long)(PAGE_CACHE_SIZE - offset)); | |
3686 | ||
3687 | kaddr = kmap_atomic(page, KM_USER0); | |
3688 | read_extent_buffer(src, kaddr + offset, src_offset, cur); | |
3689 | kunmap_atomic(kaddr, KM_USER0); | |
3690 | ||
3691 | src_offset += cur; | |
3692 | len -= cur; | |
3693 | offset = 0; | |
3694 | i++; | |
3695 | } | |
3696 | } | |
d1310b2e CM |
3697 | |
3698 | static void move_pages(struct page *dst_page, struct page *src_page, | |
3699 | unsigned long dst_off, unsigned long src_off, | |
3700 | unsigned long len) | |
3701 | { | |
3702 | char *dst_kaddr = kmap_atomic(dst_page, KM_USER0); | |
3703 | if (dst_page == src_page) { | |
3704 | memmove(dst_kaddr + dst_off, dst_kaddr + src_off, len); | |
3705 | } else { | |
3706 | char *src_kaddr = kmap_atomic(src_page, KM_USER1); | |
3707 | char *p = dst_kaddr + dst_off + len; | |
3708 | char *s = src_kaddr + src_off + len; | |
3709 | ||
3710 | while (len--) | |
3711 | *--p = *--s; | |
3712 | ||
3713 | kunmap_atomic(src_kaddr, KM_USER1); | |
3714 | } | |
3715 | kunmap_atomic(dst_kaddr, KM_USER0); | |
3716 | } | |
3717 | ||
3387206f ST |
3718 | static inline bool areas_overlap(unsigned long src, unsigned long dst, unsigned long len) |
3719 | { | |
3720 | unsigned long distance = (src > dst) ? src - dst : dst - src; | |
3721 | return distance < len; | |
3722 | } | |
3723 | ||
d1310b2e CM |
3724 | static void copy_pages(struct page *dst_page, struct page *src_page, |
3725 | unsigned long dst_off, unsigned long src_off, | |
3726 | unsigned long len) | |
3727 | { | |
3728 | char *dst_kaddr = kmap_atomic(dst_page, KM_USER0); | |
3729 | char *src_kaddr; | |
3730 | ||
3387206f | 3731 | if (dst_page != src_page) { |
d1310b2e | 3732 | src_kaddr = kmap_atomic(src_page, KM_USER1); |
3387206f | 3733 | } else { |
d1310b2e | 3734 | src_kaddr = dst_kaddr; |
3387206f ST |
3735 | BUG_ON(areas_overlap(src_off, dst_off, len)); |
3736 | } | |
d1310b2e CM |
3737 | |
3738 | memcpy(dst_kaddr + dst_off, src_kaddr + src_off, len); | |
3739 | kunmap_atomic(dst_kaddr, KM_USER0); | |
3740 | if (dst_page != src_page) | |
3741 | kunmap_atomic(src_kaddr, KM_USER1); | |
3742 | } | |
3743 | ||
3744 | void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, | |
3745 | unsigned long src_offset, unsigned long len) | |
3746 | { | |
3747 | size_t cur; | |
3748 | size_t dst_off_in_page; | |
3749 | size_t src_off_in_page; | |
3750 | size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3751 | unsigned long dst_i; | |
3752 | unsigned long src_i; | |
3753 | ||
3754 | if (src_offset + len > dst->len) { | |
d397712b CM |
3755 | printk(KERN_ERR "btrfs memmove bogus src_offset %lu move " |
3756 | "len %lu dst len %lu\n", src_offset, len, dst->len); | |
d1310b2e CM |
3757 | BUG_ON(1); |
3758 | } | |
3759 | if (dst_offset + len > dst->len) { | |
d397712b CM |
3760 | printk(KERN_ERR "btrfs memmove bogus dst_offset %lu move " |
3761 | "len %lu dst len %lu\n", dst_offset, len, dst->len); | |
d1310b2e CM |
3762 | BUG_ON(1); |
3763 | } | |
3764 | ||
d397712b | 3765 | while (len > 0) { |
d1310b2e CM |
3766 | dst_off_in_page = (start_offset + dst_offset) & |
3767 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3768 | src_off_in_page = (start_offset + src_offset) & | |
3769 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3770 | ||
3771 | dst_i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT; | |
3772 | src_i = (start_offset + src_offset) >> PAGE_CACHE_SHIFT; | |
3773 | ||
3774 | cur = min(len, (unsigned long)(PAGE_CACHE_SIZE - | |
3775 | src_off_in_page)); | |
3776 | cur = min_t(unsigned long, cur, | |
3777 | (unsigned long)(PAGE_CACHE_SIZE - dst_off_in_page)); | |
3778 | ||
3779 | copy_pages(extent_buffer_page(dst, dst_i), | |
3780 | extent_buffer_page(dst, src_i), | |
3781 | dst_off_in_page, src_off_in_page, cur); | |
3782 | ||
3783 | src_offset += cur; | |
3784 | dst_offset += cur; | |
3785 | len -= cur; | |
3786 | } | |
3787 | } | |
d1310b2e CM |
3788 | |
3789 | void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, | |
3790 | unsigned long src_offset, unsigned long len) | |
3791 | { | |
3792 | size_t cur; | |
3793 | size_t dst_off_in_page; | |
3794 | size_t src_off_in_page; | |
3795 | unsigned long dst_end = dst_offset + len - 1; | |
3796 | unsigned long src_end = src_offset + len - 1; | |
3797 | size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); | |
3798 | unsigned long dst_i; | |
3799 | unsigned long src_i; | |
3800 | ||
3801 | if (src_offset + len > dst->len) { | |
d397712b CM |
3802 | printk(KERN_ERR "btrfs memmove bogus src_offset %lu move " |
3803 | "len %lu len %lu\n", src_offset, len, dst->len); | |
d1310b2e CM |
3804 | BUG_ON(1); |
3805 | } | |
3806 | if (dst_offset + len > dst->len) { | |
d397712b CM |
3807 | printk(KERN_ERR "btrfs memmove bogus dst_offset %lu move " |
3808 | "len %lu len %lu\n", dst_offset, len, dst->len); | |
d1310b2e CM |
3809 | BUG_ON(1); |
3810 | } | |
3387206f | 3811 | if (!areas_overlap(src_offset, dst_offset, len)) { |
d1310b2e CM |
3812 | memcpy_extent_buffer(dst, dst_offset, src_offset, len); |
3813 | return; | |
3814 | } | |
d397712b | 3815 | while (len > 0) { |
d1310b2e CM |
3816 | dst_i = (start_offset + dst_end) >> PAGE_CACHE_SHIFT; |
3817 | src_i = (start_offset + src_end) >> PAGE_CACHE_SHIFT; | |
3818 | ||
3819 | dst_off_in_page = (start_offset + dst_end) & | |
3820 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3821 | src_off_in_page = (start_offset + src_end) & | |
3822 | ((unsigned long)PAGE_CACHE_SIZE - 1); | |
3823 | ||
3824 | cur = min_t(unsigned long, len, src_off_in_page + 1); | |
3825 | cur = min(cur, dst_off_in_page + 1); | |
3826 | move_pages(extent_buffer_page(dst, dst_i), | |
3827 | extent_buffer_page(dst, src_i), | |
3828 | dst_off_in_page - cur + 1, | |
3829 | src_off_in_page - cur + 1, cur); | |
3830 | ||
3831 | dst_end -= cur; | |
3832 | src_end -= cur; | |
3833 | len -= cur; | |
3834 | } | |
3835 | } | |
6af118ce | 3836 | |
19fe0a8b MX |
3837 | static inline void btrfs_release_extent_buffer_rcu(struct rcu_head *head) |
3838 | { | |
3839 | struct extent_buffer *eb = | |
3840 | container_of(head, struct extent_buffer, rcu_head); | |
3841 | ||
3842 | btrfs_release_extent_buffer(eb); | |
3843 | } | |
3844 | ||
6af118ce CM |
3845 | int try_release_extent_buffer(struct extent_io_tree *tree, struct page *page) |
3846 | { | |
3847 | u64 start = page_offset(page); | |
3848 | struct extent_buffer *eb; | |
3849 | int ret = 1; | |
6af118ce CM |
3850 | |
3851 | spin_lock(&tree->buffer_lock); | |
19fe0a8b | 3852 | eb = radix_tree_lookup(&tree->buffer, start >> PAGE_CACHE_SHIFT); |
45f49bce CM |
3853 | if (!eb) { |
3854 | spin_unlock(&tree->buffer_lock); | |
3855 | return ret; | |
3856 | } | |
6af118ce | 3857 | |
19fe0a8b | 3858 | if (test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)) { |
6af118ce CM |
3859 | ret = 0; |
3860 | goto out; | |
3861 | } | |
19fe0a8b MX |
3862 | |
3863 | /* | |
3864 | * set @eb->refs to 0 if it is already 1, and then release the @eb. | |
3865 | * Or go back. | |
3866 | */ | |
3867 | if (atomic_cmpxchg(&eb->refs, 1, 0) != 1) { | |
b9473439 CM |
3868 | ret = 0; |
3869 | goto out; | |
3870 | } | |
897ca6e9 | 3871 | |
19fe0a8b | 3872 | radix_tree_delete(&tree->buffer, start >> PAGE_CACHE_SHIFT); |
6af118ce CM |
3873 | out: |
3874 | spin_unlock(&tree->buffer_lock); | |
19fe0a8b MX |
3875 | |
3876 | /* at this point we can safely release the extent buffer */ | |
3877 | if (atomic_read(&eb->refs) == 0) | |
3878 | call_rcu(&eb->rcu_head, btrfs_release_extent_buffer_rcu); | |
6af118ce CM |
3879 | return ret; |
3880 | } |