blob: d418164a35f134842ed3af4cfd5f43666b37c89d [file] [log] [blame]
Chris Masond1310b22008-01-24 16:13:08 -05001#include <linux/bitops.h>
2#include <linux/slab.h>
3#include <linux/bio.h>
4#include <linux/mm.h>
Chris Masond1310b22008-01-24 16:13:08 -05005#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>
Chris Masond1310b22008-01-24 16:13:08 -050011#include <linux/writeback.h>
12#include <linux/pagevec.h>
Linus Torvalds268bb0c2011-05-20 12:50:29 -070013#include <linux/prefetch.h>
Dan Magenheimer90a887c2011-05-26 10:01:56 -060014#include <linux/cleancache.h>
Chris Masond1310b22008-01-24 16:13:08 -050015#include "extent_io.h"
16#include "extent_map.h"
David Woodhouse2db04962008-08-07 11:19:43 -040017#include "compat.h"
David Woodhouse902b22f2008-08-20 08:51:49 -040018#include "ctree.h"
19#include "btrfs_inode.h"
Chris Masond1310b22008-01-24 16:13:08 -050020
Chris Masond1310b22008-01-24 16:13:08 -050021static struct kmem_cache *extent_state_cache;
22static struct kmem_cache *extent_buffer_cache;
23
24static LIST_HEAD(buffers);
25static LIST_HEAD(states);
Chris Mason4bef0842008-09-08 11:18:08 -040026
Chris Masonb47eda82008-11-10 12:34:40 -050027#define LEAK_DEBUG 0
Chris Mason39351272009-02-04 09:24:05 -050028#if LEAK_DEBUG
Chris Masond3977122009-01-05 21:25:51 -050029static DEFINE_SPINLOCK(leak_lock);
Chris Mason4bef0842008-09-08 11:18:08 -040030#endif
Chris Masond1310b22008-01-24 16:13:08 -050031
Chris Masond1310b22008-01-24 16:13:08 -050032#define BUFFER_LRU_MAX 64
33
34struct tree_entry {
35 u64 start;
36 u64 end;
Chris Masond1310b22008-01-24 16:13:08 -050037 struct rb_node rb_node;
38};
39
40struct extent_page_data {
41 struct bio *bio;
42 struct extent_io_tree *tree;
43 get_extent_t *get_extent;
Chris Mason771ed682008-11-06 22:02:51 -050044
45 /* tells writepage not to lock the state bits for this range
46 * it still does the unlocking
47 */
Chris Masonffbd5172009-04-20 15:50:09 -040048 unsigned int extent_locked:1;
49
50 /* tells the submit_bio code to use a WRITE_SYNC */
51 unsigned int sync_io:1;
Chris Masond1310b22008-01-24 16:13:08 -050052};
53
54int __init extent_io_init(void)
55{
Christoph Hellwig9601e3f2009-04-13 15:33:09 +020056 extent_state_cache = kmem_cache_create("extent_state",
57 sizeof(struct extent_state), 0,
58 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
Chris Masond1310b22008-01-24 16:13:08 -050059 if (!extent_state_cache)
60 return -ENOMEM;
61
Christoph Hellwig9601e3f2009-04-13 15:33:09 +020062 extent_buffer_cache = kmem_cache_create("extent_buffers",
63 sizeof(struct extent_buffer), 0,
64 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
Chris Masond1310b22008-01-24 16:13:08 -050065 if (!extent_buffer_cache)
66 goto free_state_cache;
67 return 0;
68
69free_state_cache:
70 kmem_cache_destroy(extent_state_cache);
71 return -ENOMEM;
72}
73
74void extent_io_exit(void)
75{
76 struct extent_state *state;
Chris Mason2d2ae542008-03-26 16:24:23 -040077 struct extent_buffer *eb;
Chris Masond1310b22008-01-24 16:13:08 -050078
79 while (!list_empty(&states)) {
Chris Mason2d2ae542008-03-26 16:24:23 -040080 state = list_entry(states.next, struct extent_state, leak_list);
Chris Masond3977122009-01-05 21:25:51 -050081 printk(KERN_ERR "btrfs state leak: start %llu end %llu "
82 "state %lu in tree %p refs %d\n",
83 (unsigned long long)state->start,
84 (unsigned long long)state->end,
85 state->state, state->tree, atomic_read(&state->refs));
Chris Mason2d2ae542008-03-26 16:24:23 -040086 list_del(&state->leak_list);
Chris Masond1310b22008-01-24 16:13:08 -050087 kmem_cache_free(extent_state_cache, state);
88
89 }
90
Chris Mason2d2ae542008-03-26 16:24:23 -040091 while (!list_empty(&buffers)) {
92 eb = list_entry(buffers.next, struct extent_buffer, leak_list);
Chris Masond3977122009-01-05 21:25:51 -050093 printk(KERN_ERR "btrfs buffer leak start %llu len %lu "
94 "refs %d\n", (unsigned long long)eb->start,
95 eb->len, atomic_read(&eb->refs));
Chris Mason2d2ae542008-03-26 16:24:23 -040096 list_del(&eb->leak_list);
97 kmem_cache_free(extent_buffer_cache, eb);
98 }
Chris Masond1310b22008-01-24 16:13:08 -050099 if (extent_state_cache)
100 kmem_cache_destroy(extent_state_cache);
101 if (extent_buffer_cache)
102 kmem_cache_destroy(extent_buffer_cache);
103}
104
105void extent_io_tree_init(struct extent_io_tree *tree,
David Sterbaf993c882011-04-20 23:35:57 +0200106 struct address_space *mapping)
Chris Masond1310b22008-01-24 16:13:08 -0500107{
Eric Paris6bef4d32010-02-23 19:43:04 +0000108 tree->state = RB_ROOT;
Miao Xie19fe0a82010-10-26 20:57:29 -0400109 INIT_RADIX_TREE(&tree->buffer, GFP_ATOMIC);
Chris Masond1310b22008-01-24 16:13:08 -0500110 tree->ops = NULL;
111 tree->dirty_bytes = 0;
Chris Mason70dec802008-01-29 09:59:12 -0500112 spin_lock_init(&tree->lock);
Chris Mason6af118ce2008-07-22 11:18:07 -0400113 spin_lock_init(&tree->buffer_lock);
Chris Masond1310b22008-01-24 16:13:08 -0500114 tree->mapping = mapping;
Chris Masond1310b22008-01-24 16:13:08 -0500115}
Chris Masond1310b22008-01-24 16:13:08 -0500116
Christoph Hellwigb2950862008-12-02 09:54:17 -0500117static struct extent_state *alloc_extent_state(gfp_t mask)
Chris Masond1310b22008-01-24 16:13:08 -0500118{
119 struct extent_state *state;
Chris Mason39351272009-02-04 09:24:05 -0500120#if LEAK_DEBUG
Chris Mason2d2ae542008-03-26 16:24:23 -0400121 unsigned long flags;
Chris Mason4bef0842008-09-08 11:18:08 -0400122#endif
Chris Masond1310b22008-01-24 16:13:08 -0500123
124 state = kmem_cache_alloc(extent_state_cache, mask);
Peter2b114d12008-04-01 11:21:40 -0400125 if (!state)
Chris Masond1310b22008-01-24 16:13:08 -0500126 return state;
127 state->state = 0;
Chris Masond1310b22008-01-24 16:13:08 -0500128 state->private = 0;
Chris Mason70dec802008-01-29 09:59:12 -0500129 state->tree = NULL;
Chris Mason39351272009-02-04 09:24:05 -0500130#if LEAK_DEBUG
Chris Mason2d2ae542008-03-26 16:24:23 -0400131 spin_lock_irqsave(&leak_lock, flags);
132 list_add(&state->leak_list, &states);
133 spin_unlock_irqrestore(&leak_lock, flags);
Chris Mason4bef0842008-09-08 11:18:08 -0400134#endif
Chris Masond1310b22008-01-24 16:13:08 -0500135 atomic_set(&state->refs, 1);
136 init_waitqueue_head(&state->wq);
137 return state;
138}
Chris Masond1310b22008-01-24 16:13:08 -0500139
Chris Mason4845e442010-05-25 20:56:50 -0400140void free_extent_state(struct extent_state *state)
Chris Masond1310b22008-01-24 16:13:08 -0500141{
Chris Masond1310b22008-01-24 16:13:08 -0500142 if (!state)
143 return;
144 if (atomic_dec_and_test(&state->refs)) {
Chris Mason39351272009-02-04 09:24:05 -0500145#if LEAK_DEBUG
Chris Mason2d2ae542008-03-26 16:24:23 -0400146 unsigned long flags;
Chris Mason4bef0842008-09-08 11:18:08 -0400147#endif
Chris Mason70dec802008-01-29 09:59:12 -0500148 WARN_ON(state->tree);
Chris Mason39351272009-02-04 09:24:05 -0500149#if LEAK_DEBUG
Chris Mason2d2ae542008-03-26 16:24:23 -0400150 spin_lock_irqsave(&leak_lock, flags);
151 list_del(&state->leak_list);
152 spin_unlock_irqrestore(&leak_lock, flags);
Chris Mason4bef0842008-09-08 11:18:08 -0400153#endif
Chris Masond1310b22008-01-24 16:13:08 -0500154 kmem_cache_free(extent_state_cache, state);
155 }
156}
Chris Masond1310b22008-01-24 16:13:08 -0500157
158static struct rb_node *tree_insert(struct rb_root *root, u64 offset,
159 struct rb_node *node)
160{
Chris Masond3977122009-01-05 21:25:51 -0500161 struct rb_node **p = &root->rb_node;
162 struct rb_node *parent = NULL;
Chris Masond1310b22008-01-24 16:13:08 -0500163 struct tree_entry *entry;
164
Chris Masond3977122009-01-05 21:25:51 -0500165 while (*p) {
Chris Masond1310b22008-01-24 16:13:08 -0500166 parent = *p;
167 entry = rb_entry(parent, struct tree_entry, rb_node);
168
169 if (offset < entry->start)
170 p = &(*p)->rb_left;
171 else if (offset > entry->end)
172 p = &(*p)->rb_right;
173 else
174 return parent;
175 }
176
177 entry = rb_entry(node, struct tree_entry, rb_node);
Chris Masond1310b22008-01-24 16:13:08 -0500178 rb_link_node(node, parent, p);
179 rb_insert_color(node, root);
180 return NULL;
181}
182
Chris Mason80ea96b2008-02-01 14:51:59 -0500183static struct rb_node *__etree_search(struct extent_io_tree *tree, u64 offset,
Chris Masond1310b22008-01-24 16:13:08 -0500184 struct rb_node **prev_ret,
185 struct rb_node **next_ret)
186{
Chris Mason80ea96b2008-02-01 14:51:59 -0500187 struct rb_root *root = &tree->state;
Chris Masond3977122009-01-05 21:25:51 -0500188 struct rb_node *n = root->rb_node;
Chris Masond1310b22008-01-24 16:13:08 -0500189 struct rb_node *prev = NULL;
190 struct rb_node *orig_prev = NULL;
191 struct tree_entry *entry;
192 struct tree_entry *prev_entry = NULL;
193
Chris Masond3977122009-01-05 21:25:51 -0500194 while (n) {
Chris Masond1310b22008-01-24 16:13:08 -0500195 entry = rb_entry(n, struct tree_entry, rb_node);
196 prev = n;
197 prev_entry = entry;
198
199 if (offset < entry->start)
200 n = n->rb_left;
201 else if (offset > entry->end)
202 n = n->rb_right;
Chris Masond3977122009-01-05 21:25:51 -0500203 else
Chris Masond1310b22008-01-24 16:13:08 -0500204 return n;
205 }
206
207 if (prev_ret) {
208 orig_prev = prev;
Chris Masond3977122009-01-05 21:25:51 -0500209 while (prev && offset > prev_entry->end) {
Chris Masond1310b22008-01-24 16:13:08 -0500210 prev = rb_next(prev);
211 prev_entry = rb_entry(prev, struct tree_entry, rb_node);
212 }
213 *prev_ret = prev;
214 prev = orig_prev;
215 }
216
217 if (next_ret) {
218 prev_entry = rb_entry(prev, struct tree_entry, rb_node);
Chris Masond3977122009-01-05 21:25:51 -0500219 while (prev && offset < prev_entry->start) {
Chris Masond1310b22008-01-24 16:13:08 -0500220 prev = rb_prev(prev);
221 prev_entry = rb_entry(prev, struct tree_entry, rb_node);
222 }
223 *next_ret = prev;
224 }
225 return NULL;
226}
227
Chris Mason80ea96b2008-02-01 14:51:59 -0500228static inline struct rb_node *tree_search(struct extent_io_tree *tree,
229 u64 offset)
Chris Masond1310b22008-01-24 16:13:08 -0500230{
Chris Mason70dec802008-01-29 09:59:12 -0500231 struct rb_node *prev = NULL;
Chris Masond1310b22008-01-24 16:13:08 -0500232 struct rb_node *ret;
Chris Mason70dec802008-01-29 09:59:12 -0500233
Chris Mason80ea96b2008-02-01 14:51:59 -0500234 ret = __etree_search(tree, offset, &prev, NULL);
Chris Masond3977122009-01-05 21:25:51 -0500235 if (!ret)
Chris Masond1310b22008-01-24 16:13:08 -0500236 return prev;
237 return ret;
238}
239
Josef Bacik9ed74f22009-09-11 16:12:44 -0400240static void merge_cb(struct extent_io_tree *tree, struct extent_state *new,
241 struct extent_state *other)
242{
243 if (tree->ops && tree->ops->merge_extent_hook)
244 tree->ops->merge_extent_hook(tree->mapping->host, new,
245 other);
246}
247
Chris Masond1310b22008-01-24 16:13:08 -0500248/*
249 * utility function to look for merge candidates inside a given range.
250 * Any extents with matching state are merged together into a single
251 * extent in the tree. Extents with EXTENT_IO in their state field
252 * are not merged because the end_io handlers need to be able to do
253 * operations on them without sleeping (or doing allocations/splits).
254 *
255 * This should be called with the tree lock held.
256 */
Jeff Mahoney1bf85042011-07-21 16:56:09 +0000257static void merge_state(struct extent_io_tree *tree,
258 struct extent_state *state)
Chris Masond1310b22008-01-24 16:13:08 -0500259{
260 struct extent_state *other;
261 struct rb_node *other_node;
262
Zheng Yan5b21f2e2008-09-26 10:05:38 -0400263 if (state->state & (EXTENT_IOBITS | EXTENT_BOUNDARY))
Jeff Mahoney1bf85042011-07-21 16:56:09 +0000264 return;
Chris Masond1310b22008-01-24 16:13:08 -0500265
266 other_node = rb_prev(&state->rb_node);
267 if (other_node) {
268 other = rb_entry(other_node, struct extent_state, rb_node);
269 if (other->end == state->start - 1 &&
270 other->state == state->state) {
Josef Bacik9ed74f22009-09-11 16:12:44 -0400271 merge_cb(tree, state, other);
Chris Masond1310b22008-01-24 16:13:08 -0500272 state->start = other->start;
Chris Mason70dec802008-01-29 09:59:12 -0500273 other->tree = NULL;
Chris Masond1310b22008-01-24 16:13:08 -0500274 rb_erase(&other->rb_node, &tree->state);
275 free_extent_state(other);
276 }
277 }
278 other_node = rb_next(&state->rb_node);
279 if (other_node) {
280 other = rb_entry(other_node, struct extent_state, rb_node);
281 if (other->start == state->end + 1 &&
282 other->state == state->state) {
Josef Bacik9ed74f22009-09-11 16:12:44 -0400283 merge_cb(tree, state, other);
Josef Bacikdf98b6e2011-06-20 14:53:48 -0400284 state->end = other->end;
285 other->tree = NULL;
286 rb_erase(&other->rb_node, &tree->state);
287 free_extent_state(other);
Chris Masond1310b22008-01-24 16:13:08 -0500288 }
289 }
Chris Masond1310b22008-01-24 16:13:08 -0500290}
291
Jeff Mahoney1bf85042011-07-21 16:56:09 +0000292static void set_state_cb(struct extent_io_tree *tree,
Yan, Zheng0ca1f7c2010-05-16 10:48:47 -0400293 struct extent_state *state, int *bits)
Chris Mason291d6732008-01-29 15:55:23 -0500294{
Jeff Mahoney1bf85042011-07-21 16:56:09 +0000295 if (tree->ops && tree->ops->set_bit_hook)
296 tree->ops->set_bit_hook(tree->mapping->host, state, bits);
Chris Mason291d6732008-01-29 15:55:23 -0500297}
298
299static void clear_state_cb(struct extent_io_tree *tree,
Yan, Zheng0ca1f7c2010-05-16 10:48:47 -0400300 struct extent_state *state, int *bits)
Chris Mason291d6732008-01-29 15:55:23 -0500301{
Josef Bacik9ed74f22009-09-11 16:12:44 -0400302 if (tree->ops && tree->ops->clear_bit_hook)
303 tree->ops->clear_bit_hook(tree->mapping->host, state, bits);
Chris Mason291d6732008-01-29 15:55:23 -0500304}
305
Xiao Guangrong3150b692011-07-14 03:19:08 +0000306static void set_state_bits(struct extent_io_tree *tree,
307 struct extent_state *state, int *bits);
308
Chris Masond1310b22008-01-24 16:13:08 -0500309/*
310 * insert an extent_state struct into the tree. 'bits' are set on the
311 * struct before it is inserted.
312 *
313 * This may return -EEXIST if the extent is already there, in which case the
314 * state struct is freed.
315 *
316 * The tree lock is not taken internally. This is a utility function and
317 * probably isn't what you want to call (see set/clear_extent_bit).
318 */
319static int insert_state(struct extent_io_tree *tree,
320 struct extent_state *state, u64 start, u64 end,
Yan, Zheng0ca1f7c2010-05-16 10:48:47 -0400321 int *bits)
Chris Masond1310b22008-01-24 16:13:08 -0500322{
323 struct rb_node *node;
324
325 if (end < start) {
Chris Masond3977122009-01-05 21:25:51 -0500326 printk(KERN_ERR "btrfs end < start %llu %llu\n",
327 (unsigned long long)end,
328 (unsigned long long)start);
Chris Masond1310b22008-01-24 16:13:08 -0500329 WARN_ON(1);
330 }
Chris Masond1310b22008-01-24 16:13:08 -0500331 state->start = start;
332 state->end = end;
Josef Bacik9ed74f22009-09-11 16:12:44 -0400333
Xiao Guangrong3150b692011-07-14 03:19:08 +0000334 set_state_bits(tree, state, bits);
335
Chris Masond1310b22008-01-24 16:13:08 -0500336 node = tree_insert(&tree->state, end, &state->rb_node);
337 if (node) {
338 struct extent_state *found;
339 found = rb_entry(node, struct extent_state, rb_node);
Chris Masond3977122009-01-05 21:25:51 -0500340 printk(KERN_ERR "btrfs found node %llu %llu on insert of "
341 "%llu %llu\n", (unsigned long long)found->start,
342 (unsigned long long)found->end,
343 (unsigned long long)start, (unsigned long long)end);
Chris Masond1310b22008-01-24 16:13:08 -0500344 return -EEXIST;
345 }
Chris Mason70dec802008-01-29 09:59:12 -0500346 state->tree = tree;
Chris Masond1310b22008-01-24 16:13:08 -0500347 merge_state(tree, state);
348 return 0;
349}
350
Jeff Mahoney1bf85042011-07-21 16:56:09 +0000351static void split_cb(struct extent_io_tree *tree, struct extent_state *orig,
Josef Bacik9ed74f22009-09-11 16:12:44 -0400352 u64 split)
353{
354 if (tree->ops && tree->ops->split_extent_hook)
Jeff Mahoney1bf85042011-07-21 16:56:09 +0000355 tree->ops->split_extent_hook(tree->mapping->host, orig, split);
Josef Bacik9ed74f22009-09-11 16:12:44 -0400356}
357
Chris Masond1310b22008-01-24 16:13:08 -0500358/*
359 * split a given extent state struct in two, inserting the preallocated
360 * struct 'prealloc' as the newly created second half. 'split' indicates an
361 * offset inside 'orig' where it should be split.
362 *
363 * Before calling,
364 * the tree has 'orig' at [orig->start, orig->end]. After calling, there
365 * are two extent state structs in the tree:
366 * prealloc: [orig->start, split - 1]
367 * orig: [ split, orig->end ]
368 *
369 * The tree locks are not taken by this function. They need to be held
370 * by the caller.
371 */
372static int split_state(struct extent_io_tree *tree, struct extent_state *orig,
373 struct extent_state *prealloc, u64 split)
374{
375 struct rb_node *node;
Josef Bacik9ed74f22009-09-11 16:12:44 -0400376
377 split_cb(tree, orig, split);
378
Chris Masond1310b22008-01-24 16:13:08 -0500379 prealloc->start = orig->start;
380 prealloc->end = split - 1;
381 prealloc->state = orig->state;
382 orig->start = split;
383
384 node = tree_insert(&tree->state, prealloc->end, &prealloc->rb_node);
385 if (node) {
Chris Masond1310b22008-01-24 16:13:08 -0500386 free_extent_state(prealloc);
387 return -EEXIST;
388 }
Chris Mason70dec802008-01-29 09:59:12 -0500389 prealloc->tree = tree;
Chris Masond1310b22008-01-24 16:13:08 -0500390 return 0;
391}
392
393/*
394 * utility function to clear some bits in an extent state struct.
395 * it will optionally wake up any one waiting on this state (wake == 1), or
396 * forcibly remove the state from the tree (delete == 1).
397 *
398 * If no bits are set on the state struct after clearing things, the
399 * struct is freed and removed from the tree
400 */
401static int clear_state_bit(struct extent_io_tree *tree,
Yan, Zheng0ca1f7c2010-05-16 10:48:47 -0400402 struct extent_state *state,
403 int *bits, int wake)
Chris Masond1310b22008-01-24 16:13:08 -0500404{
Yan, Zheng0ca1f7c2010-05-16 10:48:47 -0400405 int bits_to_clear = *bits & ~EXTENT_CTLBITS;
Josef Bacik32c00af2009-10-08 13:34:05 -0400406 int ret = state->state & bits_to_clear;
Chris Masond1310b22008-01-24 16:13:08 -0500407
Yan, Zheng0ca1f7c2010-05-16 10:48:47 -0400408 if ((bits_to_clear & EXTENT_DIRTY) && (state->state & EXTENT_DIRTY)) {
Chris Masond1310b22008-01-24 16:13:08 -0500409 u64 range = state->end - state->start + 1;
410 WARN_ON(range > tree->dirty_bytes);
411 tree->dirty_bytes -= range;
412 }
Chris Mason291d6732008-01-29 15:55:23 -0500413 clear_state_cb(tree, state, bits);
Josef Bacik32c00af2009-10-08 13:34:05 -0400414 state->state &= ~bits_to_clear;
Chris Masond1310b22008-01-24 16:13:08 -0500415 if (wake)
416 wake_up(&state->wq);
Yan, Zheng0ca1f7c2010-05-16 10:48:47 -0400417 if (state->state == 0) {
Chris Mason70dec802008-01-29 09:59:12 -0500418 if (state->tree) {
Chris Masond1310b22008-01-24 16:13:08 -0500419 rb_erase(&state->rb_node, &tree->state);
Chris Mason70dec802008-01-29 09:59:12 -0500420 state->tree = NULL;
Chris Masond1310b22008-01-24 16:13:08 -0500421 free_extent_state(state);
422 } else {
423 WARN_ON(1);
424 }
425 } else {
426 merge_state(tree, state);
427 }
428 return ret;
429}
430
Xiao Guangrong82337672011-04-20 06:44:57 +0000431static struct extent_state *
432alloc_extent_state_atomic(struct extent_state *prealloc)
433{
434 if (!prealloc)
435 prealloc = alloc_extent_state(GFP_ATOMIC);
436
437 return prealloc;
438}
439
Chris Masond1310b22008-01-24 16:13:08 -0500440/*
441 * clear some bits on a range in the tree. This may require splitting
442 * or inserting elements in the tree, so the gfp mask is used to
443 * indicate which allocations or sleeping are allowed.
444 *
445 * pass 'wake' == 1 to kick any sleepers, and 'delete' == 1 to remove
446 * the given range from the tree regardless of state (ie for truncate).
447 *
448 * the range [start, end] is inclusive.
449 *
450 * This takes the tree lock, and returns < 0 on error, > 0 if any of the
451 * bits were already set, or zero if none of the bits were already set.
452 */
453int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
Chris Mason2c64c532009-09-02 15:04:12 -0400454 int bits, int wake, int delete,
455 struct extent_state **cached_state,
456 gfp_t mask)
Chris Masond1310b22008-01-24 16:13:08 -0500457{
458 struct extent_state *state;
Chris Mason2c64c532009-09-02 15:04:12 -0400459 struct extent_state *cached;
Chris Masond1310b22008-01-24 16:13:08 -0500460 struct extent_state *prealloc = NULL;
Chris Mason2c64c532009-09-02 15:04:12 -0400461 struct rb_node *next_node;
Chris Masond1310b22008-01-24 16:13:08 -0500462 struct rb_node *node;
Yan Zheng5c939df2009-05-27 09:16:03 -0400463 u64 last_end;
Chris Masond1310b22008-01-24 16:13:08 -0500464 int err;
465 int set = 0;
Josef Bacik2ac55d42010-02-03 19:33:23 +0000466 int clear = 0;
Chris Masond1310b22008-01-24 16:13:08 -0500467
Yan, Zheng0ca1f7c2010-05-16 10:48:47 -0400468 if (delete)
469 bits |= ~EXTENT_CTLBITS;
470 bits |= EXTENT_FIRST_DELALLOC;
471
Josef Bacik2ac55d42010-02-03 19:33:23 +0000472 if (bits & (EXTENT_IOBITS | EXTENT_BOUNDARY))
473 clear = 1;
Chris Masond1310b22008-01-24 16:13:08 -0500474again:
475 if (!prealloc && (mask & __GFP_WAIT)) {
476 prealloc = alloc_extent_state(mask);
477 if (!prealloc)
478 return -ENOMEM;
479 }
480
Chris Masoncad321a2008-12-17 14:51:42 -0500481 spin_lock(&tree->lock);
Chris Mason2c64c532009-09-02 15:04:12 -0400482 if (cached_state) {
483 cached = *cached_state;
Josef Bacik2ac55d42010-02-03 19:33:23 +0000484
485 if (clear) {
486 *cached_state = NULL;
487 cached_state = NULL;
488 }
489
Josef Bacikdf98b6e2011-06-20 14:53:48 -0400490 if (cached && cached->tree && cached->start <= start &&
491 cached->end > start) {
Josef Bacik2ac55d42010-02-03 19:33:23 +0000492 if (clear)
493 atomic_dec(&cached->refs);
Chris Mason2c64c532009-09-02 15:04:12 -0400494 state = cached;
Chris Mason42daec22009-09-23 19:51:09 -0400495 goto hit_next;
Chris Mason2c64c532009-09-02 15:04:12 -0400496 }
Josef Bacik2ac55d42010-02-03 19:33:23 +0000497 if (clear)
498 free_extent_state(cached);
Chris Mason2c64c532009-09-02 15:04:12 -0400499 }
Chris Masond1310b22008-01-24 16:13:08 -0500500 /*
501 * this search will find the extents that end after
502 * our range starts
503 */
Chris Mason80ea96b2008-02-01 14:51:59 -0500504 node = tree_search(tree, start);
Chris Masond1310b22008-01-24 16:13:08 -0500505 if (!node)
506 goto out;
507 state = rb_entry(node, struct extent_state, rb_node);
Chris Mason2c64c532009-09-02 15:04:12 -0400508hit_next:
Chris Masond1310b22008-01-24 16:13:08 -0500509 if (state->start > end)
510 goto out;
511 WARN_ON(state->end < start);
Yan Zheng5c939df2009-05-27 09:16:03 -0400512 last_end = state->end;
Chris Masond1310b22008-01-24 16:13:08 -0500513
514 /*
515 * | ---- desired range ---- |
516 * | state | or
517 * | ------------- state -------------- |
518 *
519 * We need to split the extent we found, and may flip
520 * bits on second half.
521 *
522 * If the extent we found extends past our range, we
523 * just split and search again. It'll get split again
524 * the next time though.
525 *
526 * If the extent we found is inside our range, we clear
527 * the desired bit on it.
528 */
529
530 if (state->start < start) {
Xiao Guangrong82337672011-04-20 06:44:57 +0000531 prealloc = alloc_extent_state_atomic(prealloc);
532 BUG_ON(!prealloc);
Chris Masond1310b22008-01-24 16:13:08 -0500533 err = split_state(tree, state, prealloc, start);
534 BUG_ON(err == -EEXIST);
535 prealloc = NULL;
536 if (err)
537 goto out;
538 if (state->end <= end) {
Yan, Zheng0ca1f7c2010-05-16 10:48:47 -0400539 set |= clear_state_bit(tree, state, &bits, wake);
Yan Zheng5c939df2009-05-27 09:16:03 -0400540 if (last_end == (u64)-1)
541 goto out;
542 start = last_end + 1;
Chris Masond1310b22008-01-24 16:13:08 -0500543 }
544 goto search_again;
545 }
546 /*
547 * | ---- desired range ---- |
548 * | state |
549 * We need to split the extent, and clear the bit
550 * on the first half
551 */
552 if (state->start <= end && state->end > end) {
Xiao Guangrong82337672011-04-20 06:44:57 +0000553 prealloc = alloc_extent_state_atomic(prealloc);
554 BUG_ON(!prealloc);
Chris Masond1310b22008-01-24 16:13:08 -0500555 err = split_state(tree, state, prealloc, end + 1);
556 BUG_ON(err == -EEXIST);
Chris Masond1310b22008-01-24 16:13:08 -0500557 if (wake)
558 wake_up(&state->wq);
Chris Mason42daec22009-09-23 19:51:09 -0400559
Yan, Zheng0ca1f7c2010-05-16 10:48:47 -0400560 set |= clear_state_bit(tree, prealloc, &bits, wake);
Josef Bacik9ed74f22009-09-11 16:12:44 -0400561
Chris Masond1310b22008-01-24 16:13:08 -0500562 prealloc = NULL;
563 goto out;
564 }
Chris Mason42daec22009-09-23 19:51:09 -0400565
Chris Mason2c64c532009-09-02 15:04:12 -0400566 if (state->end < end && prealloc && !need_resched())
567 next_node = rb_next(&state->rb_node);
568 else
569 next_node = NULL;
Chris Mason42daec22009-09-23 19:51:09 -0400570
Yan, Zheng0ca1f7c2010-05-16 10:48:47 -0400571 set |= clear_state_bit(tree, state, &bits, wake);
Yan Zheng5c939df2009-05-27 09:16:03 -0400572 if (last_end == (u64)-1)
573 goto out;
574 start = last_end + 1;
Chris Mason2c64c532009-09-02 15:04:12 -0400575 if (start <= end && next_node) {
576 state = rb_entry(next_node, struct extent_state,
577 rb_node);
578 if (state->start == start)
579 goto hit_next;
580 }
Chris Masond1310b22008-01-24 16:13:08 -0500581 goto search_again;
582
583out:
Chris Masoncad321a2008-12-17 14:51:42 -0500584 spin_unlock(&tree->lock);
Chris Masond1310b22008-01-24 16:13:08 -0500585 if (prealloc)
586 free_extent_state(prealloc);
587
588 return set;
589
590search_again:
591 if (start > end)
592 goto out;
Chris Masoncad321a2008-12-17 14:51:42 -0500593 spin_unlock(&tree->lock);
Chris Masond1310b22008-01-24 16:13:08 -0500594 if (mask & __GFP_WAIT)
595 cond_resched();
596 goto again;
597}
Chris Masond1310b22008-01-24 16:13:08 -0500598
599static int wait_on_state(struct extent_io_tree *tree,
600 struct extent_state *state)
Christoph Hellwig641f5212008-12-02 06:36:10 -0500601 __releases(tree->lock)
602 __acquires(tree->lock)
Chris Masond1310b22008-01-24 16:13:08 -0500603{
604 DEFINE_WAIT(wait);
605 prepare_to_wait(&state->wq, &wait, TASK_UNINTERRUPTIBLE);
Chris Masoncad321a2008-12-17 14:51:42 -0500606 spin_unlock(&tree->lock);
Chris Masond1310b22008-01-24 16:13:08 -0500607 schedule();
Chris Masoncad321a2008-12-17 14:51:42 -0500608 spin_lock(&tree->lock);
Chris Masond1310b22008-01-24 16:13:08 -0500609 finish_wait(&state->wq, &wait);
610 return 0;
611}
612
613/*
614 * waits for one or more bits to clear on a range in the state tree.
615 * The range [start, end] is inclusive.
616 * The tree lock is taken by this function
617 */
618int wait_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, int bits)
619{
620 struct extent_state *state;
621 struct rb_node *node;
622
Chris Masoncad321a2008-12-17 14:51:42 -0500623 spin_lock(&tree->lock);
Chris Masond1310b22008-01-24 16:13:08 -0500624again:
625 while (1) {
626 /*
627 * this search will find all the extents that end after
628 * our range starts
629 */
Chris Mason80ea96b2008-02-01 14:51:59 -0500630 node = tree_search(tree, start);
Chris Masond1310b22008-01-24 16:13:08 -0500631 if (!node)
632 break;
633
634 state = rb_entry(node, struct extent_state, rb_node);
635
636 if (state->start > end)
637 goto out;
638
639 if (state->state & bits) {
640 start = state->start;
641 atomic_inc(&state->refs);
642 wait_on_state(tree, state);
643 free_extent_state(state);
644 goto again;
645 }
646 start = state->end + 1;
647
648 if (start > end)
649 break;
650
Xiao Guangrongded91f02011-07-14 03:19:27 +0000651 cond_resched_lock(&tree->lock);
Chris Masond1310b22008-01-24 16:13:08 -0500652 }
653out:
Chris Masoncad321a2008-12-17 14:51:42 -0500654 spin_unlock(&tree->lock);
Chris Masond1310b22008-01-24 16:13:08 -0500655 return 0;
656}
Chris Masond1310b22008-01-24 16:13:08 -0500657
Jeff Mahoney1bf85042011-07-21 16:56:09 +0000658static void set_state_bits(struct extent_io_tree *tree,
Chris Masond1310b22008-01-24 16:13:08 -0500659 struct extent_state *state,
Yan, Zheng0ca1f7c2010-05-16 10:48:47 -0400660 int *bits)
Chris Masond1310b22008-01-24 16:13:08 -0500661{
Yan, Zheng0ca1f7c2010-05-16 10:48:47 -0400662 int bits_to_set = *bits & ~EXTENT_CTLBITS;
Josef Bacik9ed74f22009-09-11 16:12:44 -0400663
Jeff Mahoney1bf85042011-07-21 16:56:09 +0000664 set_state_cb(tree, state, bits);
Yan, Zheng0ca1f7c2010-05-16 10:48:47 -0400665 if ((bits_to_set & EXTENT_DIRTY) && !(state->state & EXTENT_DIRTY)) {
Chris Masond1310b22008-01-24 16:13:08 -0500666 u64 range = state->end - state->start + 1;
667 tree->dirty_bytes += range;
668 }
Yan, Zheng0ca1f7c2010-05-16 10:48:47 -0400669 state->state |= bits_to_set;
Chris Masond1310b22008-01-24 16:13:08 -0500670}
671
Chris Mason2c64c532009-09-02 15:04:12 -0400672static void cache_state(struct extent_state *state,
673 struct extent_state **cached_ptr)
674{
675 if (cached_ptr && !(*cached_ptr)) {
676 if (state->state & (EXTENT_IOBITS | EXTENT_BOUNDARY)) {
677 *cached_ptr = state;
678 atomic_inc(&state->refs);
679 }
680 }
681}
682
Arne Jansen507903b2011-04-06 10:02:20 +0000683static void uncache_state(struct extent_state **cached_ptr)
684{
685 if (cached_ptr && (*cached_ptr)) {
686 struct extent_state *state = *cached_ptr;
Chris Mason109b36a2011-04-12 13:57:39 -0400687 *cached_ptr = NULL;
688 free_extent_state(state);
Arne Jansen507903b2011-04-06 10:02:20 +0000689 }
690}
691
Chris Masond1310b22008-01-24 16:13:08 -0500692/*
Chris Mason1edbb732009-09-02 13:24:36 -0400693 * set some bits on a range in the tree. This may require allocations or
694 * sleeping, so the gfp mask is used to indicate what is allowed.
Chris Masond1310b22008-01-24 16:13:08 -0500695 *
Chris Mason1edbb732009-09-02 13:24:36 -0400696 * If any of the exclusive bits are set, this will fail with -EEXIST if some
697 * part of the range already has the desired bits set. The start of the
698 * existing range is returned in failed_start in this case.
Chris Masond1310b22008-01-24 16:13:08 -0500699 *
Chris Mason1edbb732009-09-02 13:24:36 -0400700 * [start, end] is inclusive This takes the tree lock.
Chris Masond1310b22008-01-24 16:13:08 -0500701 */
Chris Mason1edbb732009-09-02 13:24:36 -0400702
Chris Mason4845e442010-05-25 20:56:50 -0400703int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
704 int bits, int exclusive_bits, u64 *failed_start,
705 struct extent_state **cached_state, gfp_t mask)
Chris Masond1310b22008-01-24 16:13:08 -0500706{
707 struct extent_state *state;
708 struct extent_state *prealloc = NULL;
709 struct rb_node *node;
Chris Masond1310b22008-01-24 16:13:08 -0500710 int err = 0;
Chris Masond1310b22008-01-24 16:13:08 -0500711 u64 last_start;
712 u64 last_end;
Chris Mason42daec22009-09-23 19:51:09 -0400713
Yan, Zheng0ca1f7c2010-05-16 10:48:47 -0400714 bits |= EXTENT_FIRST_DELALLOC;
Chris Masond1310b22008-01-24 16:13:08 -0500715again:
716 if (!prealloc && (mask & __GFP_WAIT)) {
717 prealloc = alloc_extent_state(mask);
Xiao Guangrong82337672011-04-20 06:44:57 +0000718 BUG_ON(!prealloc);
Chris Masond1310b22008-01-24 16:13:08 -0500719 }
720
Chris Masoncad321a2008-12-17 14:51:42 -0500721 spin_lock(&tree->lock);
Chris Mason9655d292009-09-02 15:22:30 -0400722 if (cached_state && *cached_state) {
723 state = *cached_state;
Josef Bacikdf98b6e2011-06-20 14:53:48 -0400724 if (state->start <= start && state->end > start &&
725 state->tree) {
Chris Mason9655d292009-09-02 15:22:30 -0400726 node = &state->rb_node;
727 goto hit_next;
728 }
729 }
Chris Masond1310b22008-01-24 16:13:08 -0500730 /*
731 * this search will find all the extents that end after
732 * our range starts.
733 */
Chris Mason80ea96b2008-02-01 14:51:59 -0500734 node = tree_search(tree, start);
Chris Masond1310b22008-01-24 16:13:08 -0500735 if (!node) {
Xiao Guangrong82337672011-04-20 06:44:57 +0000736 prealloc = alloc_extent_state_atomic(prealloc);
737 BUG_ON(!prealloc);
Yan, Zheng0ca1f7c2010-05-16 10:48:47 -0400738 err = insert_state(tree, prealloc, start, end, &bits);
Chris Masond1310b22008-01-24 16:13:08 -0500739 prealloc = NULL;
740 BUG_ON(err == -EEXIST);
741 goto out;
742 }
Chris Masond1310b22008-01-24 16:13:08 -0500743 state = rb_entry(node, struct extent_state, rb_node);
Chris Mason40431d62009-08-05 12:57:59 -0400744hit_next:
Chris Masond1310b22008-01-24 16:13:08 -0500745 last_start = state->start;
746 last_end = state->end;
747
748 /*
749 * | ---- desired range ---- |
750 * | state |
751 *
752 * Just lock what we found and keep going
753 */
754 if (state->start == start && state->end <= end) {
Chris Mason40431d62009-08-05 12:57:59 -0400755 struct rb_node *next_node;
Chris Mason1edbb732009-09-02 13:24:36 -0400756 if (state->state & exclusive_bits) {
Chris Masond1310b22008-01-24 16:13:08 -0500757 *failed_start = state->start;
758 err = -EEXIST;
759 goto out;
760 }
Chris Mason42daec22009-09-23 19:51:09 -0400761
Jeff Mahoney1bf85042011-07-21 16:56:09 +0000762 set_state_bits(tree, state, &bits);
Josef Bacik9ed74f22009-09-11 16:12:44 -0400763
Chris Mason2c64c532009-09-02 15:04:12 -0400764 cache_state(state, cached_state);
Chris Masond1310b22008-01-24 16:13:08 -0500765 merge_state(tree, state);
Yan Zheng5c939df2009-05-27 09:16:03 -0400766 if (last_end == (u64)-1)
767 goto out;
Chris Mason40431d62009-08-05 12:57:59 -0400768
Yan Zheng5c939df2009-05-27 09:16:03 -0400769 start = last_end + 1;
Josef Bacikdf98b6e2011-06-20 14:53:48 -0400770 next_node = rb_next(&state->rb_node);
Xiao Guangrongc7f895a2011-04-20 06:45:49 +0000771 if (next_node && start < end && prealloc && !need_resched()) {
772 state = rb_entry(next_node, struct extent_state,
773 rb_node);
774 if (state->start == start)
775 goto hit_next;
Chris Mason40431d62009-08-05 12:57:59 -0400776 }
Chris Masond1310b22008-01-24 16:13:08 -0500777 goto search_again;
778 }
779
780 /*
781 * | ---- desired range ---- |
782 * | state |
783 * or
784 * | ------------- state -------------- |
785 *
786 * We need to split the extent we found, and may flip bits on
787 * second half.
788 *
789 * If the extent we found extends past our
790 * range, we just split and search again. It'll get split
791 * again the next time though.
792 *
793 * If the extent we found is inside our range, we set the
794 * desired bit on it.
795 */
796 if (state->start < start) {
Chris Mason1edbb732009-09-02 13:24:36 -0400797 if (state->state & exclusive_bits) {
Chris Masond1310b22008-01-24 16:13:08 -0500798 *failed_start = start;
799 err = -EEXIST;
800 goto out;
801 }
Xiao Guangrong82337672011-04-20 06:44:57 +0000802
803 prealloc = alloc_extent_state_atomic(prealloc);
804 BUG_ON(!prealloc);
Chris Masond1310b22008-01-24 16:13:08 -0500805 err = split_state(tree, state, prealloc, start);
806 BUG_ON(err == -EEXIST);
807 prealloc = NULL;
808 if (err)
809 goto out;
810 if (state->end <= end) {
Jeff Mahoney1bf85042011-07-21 16:56:09 +0000811 set_state_bits(tree, state, &bits);
Chris Mason2c64c532009-09-02 15:04:12 -0400812 cache_state(state, cached_state);
Chris Masond1310b22008-01-24 16:13:08 -0500813 merge_state(tree, state);
Yan Zheng5c939df2009-05-27 09:16:03 -0400814 if (last_end == (u64)-1)
815 goto out;
816 start = last_end + 1;
Chris Masond1310b22008-01-24 16:13:08 -0500817 }
818 goto search_again;
819 }
820 /*
821 * | ---- desired range ---- |
822 * | state | or | state |
823 *
824 * There's a hole, we need to insert something in it and
825 * ignore the extent we found.
826 */
827 if (state->start > start) {
828 u64 this_end;
829 if (end < last_start)
830 this_end = end;
831 else
Chris Masond3977122009-01-05 21:25:51 -0500832 this_end = last_start - 1;
Xiao Guangrong82337672011-04-20 06:44:57 +0000833
834 prealloc = alloc_extent_state_atomic(prealloc);
835 BUG_ON(!prealloc);
Xiao Guangrongc7f895a2011-04-20 06:45:49 +0000836
837 /*
838 * Avoid to free 'prealloc' if it can be merged with
839 * the later extent.
840 */
Chris Masond1310b22008-01-24 16:13:08 -0500841 err = insert_state(tree, prealloc, start, this_end,
Yan, Zheng0ca1f7c2010-05-16 10:48:47 -0400842 &bits);
Josef Bacik9ed74f22009-09-11 16:12:44 -0400843 BUG_ON(err == -EEXIST);
844 if (err) {
Xiao Guangrongc7f895a2011-04-20 06:45:49 +0000845 free_extent_state(prealloc);
Josef Bacik9ed74f22009-09-11 16:12:44 -0400846 prealloc = NULL;
847 goto out;
848 }
Chris Mason2c64c532009-09-02 15:04:12 -0400849 cache_state(prealloc, cached_state);
Chris Masond1310b22008-01-24 16:13:08 -0500850 prealloc = NULL;
Chris Masond1310b22008-01-24 16:13:08 -0500851 start = this_end + 1;
852 goto search_again;
853 }
854 /*
855 * | ---- desired range ---- |
856 * | state |
857 * We need to split the extent, and set the bit
858 * on the first half
859 */
860 if (state->start <= end && state->end > end) {
Chris Mason1edbb732009-09-02 13:24:36 -0400861 if (state->state & exclusive_bits) {
Chris Masond1310b22008-01-24 16:13:08 -0500862 *failed_start = start;
863 err = -EEXIST;
864 goto out;
865 }
Xiao Guangrong82337672011-04-20 06:44:57 +0000866
867 prealloc = alloc_extent_state_atomic(prealloc);
868 BUG_ON(!prealloc);
Chris Masond1310b22008-01-24 16:13:08 -0500869 err = split_state(tree, state, prealloc, end + 1);
870 BUG_ON(err == -EEXIST);
871
Jeff Mahoney1bf85042011-07-21 16:56:09 +0000872 set_state_bits(tree, prealloc, &bits);
Chris Mason2c64c532009-09-02 15:04:12 -0400873 cache_state(prealloc, cached_state);
Chris Masond1310b22008-01-24 16:13:08 -0500874 merge_state(tree, prealloc);
875 prealloc = NULL;
876 goto out;
877 }
878
879 goto search_again;
880
881out:
Chris Masoncad321a2008-12-17 14:51:42 -0500882 spin_unlock(&tree->lock);
Chris Masond1310b22008-01-24 16:13:08 -0500883 if (prealloc)
884 free_extent_state(prealloc);
885
886 return err;
887
888search_again:
889 if (start > end)
890 goto out;
Chris Masoncad321a2008-12-17 14:51:42 -0500891 spin_unlock(&tree->lock);
Chris Masond1310b22008-01-24 16:13:08 -0500892 if (mask & __GFP_WAIT)
893 cond_resched();
894 goto again;
895}
Chris Masond1310b22008-01-24 16:13:08 -0500896
897/* wrappers around set/clear extent bit */
898int set_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end,
899 gfp_t mask)
900{
901 return set_extent_bit(tree, start, end, EXTENT_DIRTY, 0, NULL,
Chris Mason2c64c532009-09-02 15:04:12 -0400902 NULL, mask);
Chris Masond1310b22008-01-24 16:13:08 -0500903}
Chris Masond1310b22008-01-24 16:13:08 -0500904
905int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
906 int bits, gfp_t mask)
907{
908 return set_extent_bit(tree, start, end, bits, 0, NULL,
Chris Mason2c64c532009-09-02 15:04:12 -0400909 NULL, mask);
Chris Masond1310b22008-01-24 16:13:08 -0500910}
Chris Masond1310b22008-01-24 16:13:08 -0500911
912int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
913 int bits, gfp_t mask)
914{
Chris Mason2c64c532009-09-02 15:04:12 -0400915 return clear_extent_bit(tree, start, end, bits, 0, 0, NULL, mask);
Chris Masond1310b22008-01-24 16:13:08 -0500916}
Chris Masond1310b22008-01-24 16:13:08 -0500917
918int set_extent_delalloc(struct extent_io_tree *tree, u64 start, u64 end,
Josef Bacik2ac55d42010-02-03 19:33:23 +0000919 struct extent_state **cached_state, gfp_t mask)
Chris Masond1310b22008-01-24 16:13:08 -0500920{
921 return set_extent_bit(tree, start, end,
Chris Mason40431d62009-08-05 12:57:59 -0400922 EXTENT_DELALLOC | EXTENT_DIRTY | EXTENT_UPTODATE,
Josef Bacik2ac55d42010-02-03 19:33:23 +0000923 0, NULL, cached_state, mask);
Chris Masond1310b22008-01-24 16:13:08 -0500924}
Chris Masond1310b22008-01-24 16:13:08 -0500925
926int clear_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end,
927 gfp_t mask)
928{
929 return clear_extent_bit(tree, start, end,
Josef Bacik32c00af2009-10-08 13:34:05 -0400930 EXTENT_DIRTY | EXTENT_DELALLOC |
Yan, Zheng0ca1f7c2010-05-16 10:48:47 -0400931 EXTENT_DO_ACCOUNTING, 0, 0, NULL, mask);
Chris Masond1310b22008-01-24 16:13:08 -0500932}
Chris Masond1310b22008-01-24 16:13:08 -0500933
934int set_extent_new(struct extent_io_tree *tree, u64 start, u64 end,
935 gfp_t mask)
936{
937 return set_extent_bit(tree, start, end, EXTENT_NEW, 0, NULL,
Chris Mason2c64c532009-09-02 15:04:12 -0400938 NULL, mask);
Chris Masond1310b22008-01-24 16:13:08 -0500939}
Chris Masond1310b22008-01-24 16:13:08 -0500940
Chris Masond1310b22008-01-24 16:13:08 -0500941int set_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end,
Arne Jansen507903b2011-04-06 10:02:20 +0000942 struct extent_state **cached_state, gfp_t mask)
Chris Masond1310b22008-01-24 16:13:08 -0500943{
Arne Jansen507903b2011-04-06 10:02:20 +0000944 return set_extent_bit(tree, start, end, EXTENT_UPTODATE, 0,
945 NULL, cached_state, mask);
Chris Masond1310b22008-01-24 16:13:08 -0500946}
Chris Masond1310b22008-01-24 16:13:08 -0500947
Chris Masond3977122009-01-05 21:25:51 -0500948static int clear_extent_uptodate(struct extent_io_tree *tree, u64 start,
Josef Bacik2ac55d42010-02-03 19:33:23 +0000949 u64 end, struct extent_state **cached_state,
950 gfp_t mask)
Chris Masond1310b22008-01-24 16:13:08 -0500951{
Chris Mason2c64c532009-09-02 15:04:12 -0400952 return clear_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, 0,
Josef Bacik2ac55d42010-02-03 19:33:23 +0000953 cached_state, mask);
Chris Masond1310b22008-01-24 16:13:08 -0500954}
Chris Masond1310b22008-01-24 16:13:08 -0500955
Chris Masond352ac62008-09-29 15:18:18 -0400956/*
957 * either insert or lock state struct between start and end use mask to tell
958 * us if waiting is desired.
959 */
Chris Mason1edbb732009-09-02 13:24:36 -0400960int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
Chris Mason2c64c532009-09-02 15:04:12 -0400961 int bits, struct extent_state **cached_state, gfp_t mask)
Chris Masond1310b22008-01-24 16:13:08 -0500962{
963 int err;
964 u64 failed_start;
965 while (1) {
Chris Mason1edbb732009-09-02 13:24:36 -0400966 err = set_extent_bit(tree, start, end, EXTENT_LOCKED | bits,
Chris Mason2c64c532009-09-02 15:04:12 -0400967 EXTENT_LOCKED, &failed_start,
968 cached_state, mask);
Chris Masond1310b22008-01-24 16:13:08 -0500969 if (err == -EEXIST && (mask & __GFP_WAIT)) {
970 wait_extent_bit(tree, failed_start, end, EXTENT_LOCKED);
971 start = failed_start;
972 } else {
973 break;
974 }
975 WARN_ON(start > end);
976 }
977 return err;
978}
Chris Masond1310b22008-01-24 16:13:08 -0500979
Chris Mason1edbb732009-09-02 13:24:36 -0400980int lock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask)
981{
Chris Mason2c64c532009-09-02 15:04:12 -0400982 return lock_extent_bits(tree, start, end, 0, NULL, mask);
Chris Mason1edbb732009-09-02 13:24:36 -0400983}
984
Josef Bacik25179202008-10-29 14:49:05 -0400985int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end,
986 gfp_t mask)
987{
988 int err;
989 u64 failed_start;
990
Chris Mason2c64c532009-09-02 15:04:12 -0400991 err = set_extent_bit(tree, start, end, EXTENT_LOCKED, EXTENT_LOCKED,
992 &failed_start, NULL, mask);
Yan Zheng66435582008-10-30 14:19:50 -0400993 if (err == -EEXIST) {
994 if (failed_start > start)
995 clear_extent_bit(tree, start, failed_start - 1,
Chris Mason2c64c532009-09-02 15:04:12 -0400996 EXTENT_LOCKED, 1, 0, NULL, mask);
Josef Bacik25179202008-10-29 14:49:05 -0400997 return 0;
Yan Zheng66435582008-10-30 14:19:50 -0400998 }
Josef Bacik25179202008-10-29 14:49:05 -0400999 return 1;
1000}
Josef Bacik25179202008-10-29 14:49:05 -04001001
Chris Mason2c64c532009-09-02 15:04:12 -04001002int unlock_extent_cached(struct extent_io_tree *tree, u64 start, u64 end,
1003 struct extent_state **cached, gfp_t mask)
1004{
1005 return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, cached,
1006 mask);
1007}
1008
Arne Jansen507903b2011-04-06 10:02:20 +00001009int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask)
Chris Masond1310b22008-01-24 16:13:08 -05001010{
Chris Mason2c64c532009-09-02 15:04:12 -04001011 return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, NULL,
1012 mask);
Chris Masond1310b22008-01-24 16:13:08 -05001013}
Chris Masond1310b22008-01-24 16:13:08 -05001014
1015/*
Chris Masond1310b22008-01-24 16:13:08 -05001016 * helper function to set both pages and extents in the tree writeback
1017 */
Christoph Hellwigb2950862008-12-02 09:54:17 -05001018static int set_range_writeback(struct extent_io_tree *tree, u64 start, u64 end)
Chris Masond1310b22008-01-24 16:13:08 -05001019{
1020 unsigned long index = start >> PAGE_CACHE_SHIFT;
1021 unsigned long end_index = end >> PAGE_CACHE_SHIFT;
1022 struct page *page;
1023
1024 while (index <= end_index) {
1025 page = find_get_page(tree->mapping, index);
1026 BUG_ON(!page);
1027 set_page_writeback(page);
1028 page_cache_release(page);
1029 index++;
1030 }
Chris Masond1310b22008-01-24 16:13:08 -05001031 return 0;
1032}
Chris Masond1310b22008-01-24 16:13:08 -05001033
Chris Masond352ac62008-09-29 15:18:18 -04001034/* find the first state struct with 'bits' set after 'start', and
1035 * return it. tree->lock must be held. NULL will returned if
1036 * nothing was found after 'start'
1037 */
Chris Masond7fc6402008-02-18 12:12:38 -05001038struct extent_state *find_first_extent_bit_state(struct extent_io_tree *tree,
1039 u64 start, int bits)
1040{
1041 struct rb_node *node;
1042 struct extent_state *state;
1043
1044 /*
1045 * this search will find all the extents that end after
1046 * our range starts.
1047 */
1048 node = tree_search(tree, start);
Chris Masond3977122009-01-05 21:25:51 -05001049 if (!node)
Chris Masond7fc6402008-02-18 12:12:38 -05001050 goto out;
Chris Masond7fc6402008-02-18 12:12:38 -05001051
Chris Masond3977122009-01-05 21:25:51 -05001052 while (1) {
Chris Masond7fc6402008-02-18 12:12:38 -05001053 state = rb_entry(node, struct extent_state, rb_node);
Chris Masond3977122009-01-05 21:25:51 -05001054 if (state->end >= start && (state->state & bits))
Chris Masond7fc6402008-02-18 12:12:38 -05001055 return state;
Chris Masond3977122009-01-05 21:25:51 -05001056
Chris Masond7fc6402008-02-18 12:12:38 -05001057 node = rb_next(node);
1058 if (!node)
1059 break;
1060 }
1061out:
1062 return NULL;
1063}
Chris Masond7fc6402008-02-18 12:12:38 -05001064
Chris Masond352ac62008-09-29 15:18:18 -04001065/*
Xiao Guangrong69261c42011-07-14 03:19:45 +00001066 * find the first offset in the io tree with 'bits' set. zero is
1067 * returned if we find something, and *start_ret and *end_ret are
1068 * set to reflect the state struct that was found.
1069 *
1070 * If nothing was found, 1 is returned, < 0 on error
1071 */
1072int find_first_extent_bit(struct extent_io_tree *tree, u64 start,
1073 u64 *start_ret, u64 *end_ret, int bits)
1074{
1075 struct extent_state *state;
1076 int ret = 1;
1077
1078 spin_lock(&tree->lock);
1079 state = find_first_extent_bit_state(tree, start, bits);
1080 if (state) {
1081 *start_ret = state->start;
1082 *end_ret = state->end;
1083 ret = 0;
1084 }
1085 spin_unlock(&tree->lock);
1086 return ret;
1087}
1088
1089/*
Chris Masond352ac62008-09-29 15:18:18 -04001090 * find a contiguous range of bytes in the file marked as delalloc, not
1091 * more than 'max_bytes'. start and end are used to return the range,
1092 *
1093 * 1 is returned if we find something, 0 if nothing was in the tree
1094 */
Chris Masonc8b97812008-10-29 14:49:59 -04001095static noinline u64 find_delalloc_range(struct extent_io_tree *tree,
Josef Bacikc2a128d2010-02-02 21:19:11 +00001096 u64 *start, u64 *end, u64 max_bytes,
1097 struct extent_state **cached_state)
Chris Masond1310b22008-01-24 16:13:08 -05001098{
1099 struct rb_node *node;
1100 struct extent_state *state;
1101 u64 cur_start = *start;
1102 u64 found = 0;
1103 u64 total_bytes = 0;
1104
Chris Masoncad321a2008-12-17 14:51:42 -05001105 spin_lock(&tree->lock);
Chris Masonc8b97812008-10-29 14:49:59 -04001106
Chris Masond1310b22008-01-24 16:13:08 -05001107 /*
1108 * this search will find all the extents that end after
1109 * our range starts.
1110 */
Chris Mason80ea96b2008-02-01 14:51:59 -05001111 node = tree_search(tree, cur_start);
Peter2b114d12008-04-01 11:21:40 -04001112 if (!node) {
Chris Mason3b951512008-04-17 11:29:12 -04001113 if (!found)
1114 *end = (u64)-1;
Chris Masond1310b22008-01-24 16:13:08 -05001115 goto out;
1116 }
1117
Chris Masond3977122009-01-05 21:25:51 -05001118 while (1) {
Chris Masond1310b22008-01-24 16:13:08 -05001119 state = rb_entry(node, struct extent_state, rb_node);
Zheng Yan5b21f2e2008-09-26 10:05:38 -04001120 if (found && (state->start != cur_start ||
1121 (state->state & EXTENT_BOUNDARY))) {
Chris Masond1310b22008-01-24 16:13:08 -05001122 goto out;
1123 }
1124 if (!(state->state & EXTENT_DELALLOC)) {
1125 if (!found)
1126 *end = state->end;
1127 goto out;
1128 }
Josef Bacikc2a128d2010-02-02 21:19:11 +00001129 if (!found) {
Chris Masond1310b22008-01-24 16:13:08 -05001130 *start = state->start;
Josef Bacikc2a128d2010-02-02 21:19:11 +00001131 *cached_state = state;
1132 atomic_inc(&state->refs);
1133 }
Chris Masond1310b22008-01-24 16:13:08 -05001134 found++;
1135 *end = state->end;
1136 cur_start = state->end + 1;
1137 node = rb_next(node);
1138 if (!node)
1139 break;
1140 total_bytes += state->end - state->start + 1;
1141 if (total_bytes >= max_bytes)
1142 break;
1143 }
1144out:
Chris Masoncad321a2008-12-17 14:51:42 -05001145 spin_unlock(&tree->lock);
Chris Masond1310b22008-01-24 16:13:08 -05001146 return found;
1147}
1148
Chris Masonc8b97812008-10-29 14:49:59 -04001149static noinline int __unlock_for_delalloc(struct inode *inode,
1150 struct page *locked_page,
1151 u64 start, u64 end)
1152{
1153 int ret;
1154 struct page *pages[16];
1155 unsigned long index = start >> PAGE_CACHE_SHIFT;
1156 unsigned long end_index = end >> PAGE_CACHE_SHIFT;
1157 unsigned long nr_pages = end_index - index + 1;
1158 int i;
1159
1160 if (index == locked_page->index && end_index == index)
1161 return 0;
1162
Chris Masond3977122009-01-05 21:25:51 -05001163 while (nr_pages > 0) {
Chris Masonc8b97812008-10-29 14:49:59 -04001164 ret = find_get_pages_contig(inode->i_mapping, index,
Chris Mason5b050f02008-11-11 09:34:41 -05001165 min_t(unsigned long, nr_pages,
1166 ARRAY_SIZE(pages)), pages);
Chris Masonc8b97812008-10-29 14:49:59 -04001167 for (i = 0; i < ret; i++) {
1168 if (pages[i] != locked_page)
1169 unlock_page(pages[i]);
1170 page_cache_release(pages[i]);
1171 }
1172 nr_pages -= ret;
1173 index += ret;
1174 cond_resched();
1175 }
1176 return 0;
1177}
1178
1179static noinline int lock_delalloc_pages(struct inode *inode,
1180 struct page *locked_page,
1181 u64 delalloc_start,
1182 u64 delalloc_end)
1183{
1184 unsigned long index = delalloc_start >> PAGE_CACHE_SHIFT;
1185 unsigned long start_index = index;
1186 unsigned long end_index = delalloc_end >> PAGE_CACHE_SHIFT;
1187 unsigned long pages_locked = 0;
1188 struct page *pages[16];
1189 unsigned long nrpages;
1190 int ret;
1191 int i;
1192
1193 /* the caller is responsible for locking the start index */
1194 if (index == locked_page->index && index == end_index)
1195 return 0;
1196
1197 /* skip the page at the start index */
1198 nrpages = end_index - index + 1;
Chris Masond3977122009-01-05 21:25:51 -05001199 while (nrpages > 0) {
Chris Masonc8b97812008-10-29 14:49:59 -04001200 ret = find_get_pages_contig(inode->i_mapping, index,
Chris Mason5b050f02008-11-11 09:34:41 -05001201 min_t(unsigned long,
1202 nrpages, ARRAY_SIZE(pages)), pages);
Chris Masonc8b97812008-10-29 14:49:59 -04001203 if (ret == 0) {
1204 ret = -EAGAIN;
1205 goto done;
1206 }
1207 /* now we have an array of pages, lock them all */
1208 for (i = 0; i < ret; i++) {
1209 /*
1210 * the caller is taking responsibility for
1211 * locked_page
1212 */
Chris Mason771ed682008-11-06 22:02:51 -05001213 if (pages[i] != locked_page) {
Chris Masonc8b97812008-10-29 14:49:59 -04001214 lock_page(pages[i]);
Chris Masonf2b1c412008-11-10 07:31:30 -05001215 if (!PageDirty(pages[i]) ||
1216 pages[i]->mapping != inode->i_mapping) {
Chris Mason771ed682008-11-06 22:02:51 -05001217 ret = -EAGAIN;
1218 unlock_page(pages[i]);
1219 page_cache_release(pages[i]);
1220 goto done;
1221 }
1222 }
Chris Masonc8b97812008-10-29 14:49:59 -04001223 page_cache_release(pages[i]);
Chris Mason771ed682008-11-06 22:02:51 -05001224 pages_locked++;
Chris Masonc8b97812008-10-29 14:49:59 -04001225 }
Chris Masonc8b97812008-10-29 14:49:59 -04001226 nrpages -= ret;
1227 index += ret;
1228 cond_resched();
1229 }
1230 ret = 0;
1231done:
1232 if (ret && pages_locked) {
1233 __unlock_for_delalloc(inode, locked_page,
1234 delalloc_start,
1235 ((u64)(start_index + pages_locked - 1)) <<
1236 PAGE_CACHE_SHIFT);
1237 }
1238 return ret;
1239}
1240
1241/*
1242 * find a contiguous range of bytes in the file marked as delalloc, not
1243 * more than 'max_bytes'. start and end are used to return the range,
1244 *
1245 * 1 is returned if we find something, 0 if nothing was in the tree
1246 */
1247static noinline u64 find_lock_delalloc_range(struct inode *inode,
1248 struct extent_io_tree *tree,
1249 struct page *locked_page,
1250 u64 *start, u64 *end,
1251 u64 max_bytes)
1252{
1253 u64 delalloc_start;
1254 u64 delalloc_end;
1255 u64 found;
Chris Mason9655d292009-09-02 15:22:30 -04001256 struct extent_state *cached_state = NULL;
Chris Masonc8b97812008-10-29 14:49:59 -04001257 int ret;
1258 int loops = 0;
1259
1260again:
1261 /* step one, find a bunch of delalloc bytes starting at start */
1262 delalloc_start = *start;
1263 delalloc_end = 0;
1264 found = find_delalloc_range(tree, &delalloc_start, &delalloc_end,
Josef Bacikc2a128d2010-02-02 21:19:11 +00001265 max_bytes, &cached_state);
Chris Mason70b99e62008-10-31 12:46:39 -04001266 if (!found || delalloc_end <= *start) {
Chris Masonc8b97812008-10-29 14:49:59 -04001267 *start = delalloc_start;
1268 *end = delalloc_end;
Josef Bacikc2a128d2010-02-02 21:19:11 +00001269 free_extent_state(cached_state);
Chris Masonc8b97812008-10-29 14:49:59 -04001270 return found;
1271 }
1272
1273 /*
Chris Mason70b99e62008-10-31 12:46:39 -04001274 * start comes from the offset of locked_page. We have to lock
1275 * pages in order, so we can't process delalloc bytes before
1276 * locked_page
1277 */
Chris Masond3977122009-01-05 21:25:51 -05001278 if (delalloc_start < *start)
Chris Mason70b99e62008-10-31 12:46:39 -04001279 delalloc_start = *start;
Chris Mason70b99e62008-10-31 12:46:39 -04001280
1281 /*
Chris Masonc8b97812008-10-29 14:49:59 -04001282 * make sure to limit the number of pages we try to lock down
1283 * if we're looping.
1284 */
Chris Masond3977122009-01-05 21:25:51 -05001285 if (delalloc_end + 1 - delalloc_start > max_bytes && loops)
Chris Mason771ed682008-11-06 22:02:51 -05001286 delalloc_end = delalloc_start + PAGE_CACHE_SIZE - 1;
Chris Masond3977122009-01-05 21:25:51 -05001287
Chris Masonc8b97812008-10-29 14:49:59 -04001288 /* step two, lock all the pages after the page that has start */
1289 ret = lock_delalloc_pages(inode, locked_page,
1290 delalloc_start, delalloc_end);
1291 if (ret == -EAGAIN) {
1292 /* some of the pages are gone, lets avoid looping by
1293 * shortening the size of the delalloc range we're searching
1294 */
Chris Mason9655d292009-09-02 15:22:30 -04001295 free_extent_state(cached_state);
Chris Masonc8b97812008-10-29 14:49:59 -04001296 if (!loops) {
1297 unsigned long offset = (*start) & (PAGE_CACHE_SIZE - 1);
1298 max_bytes = PAGE_CACHE_SIZE - offset;
1299 loops = 1;
1300 goto again;
1301 } else {
1302 found = 0;
1303 goto out_failed;
1304 }
1305 }
1306 BUG_ON(ret);
1307
1308 /* step three, lock the state bits for the whole range */
Chris Mason9655d292009-09-02 15:22:30 -04001309 lock_extent_bits(tree, delalloc_start, delalloc_end,
1310 0, &cached_state, GFP_NOFS);
Chris Masonc8b97812008-10-29 14:49:59 -04001311
1312 /* then test to make sure it is all still delalloc */
1313 ret = test_range_bit(tree, delalloc_start, delalloc_end,
Chris Mason9655d292009-09-02 15:22:30 -04001314 EXTENT_DELALLOC, 1, cached_state);
Chris Masonc8b97812008-10-29 14:49:59 -04001315 if (!ret) {
Chris Mason9655d292009-09-02 15:22:30 -04001316 unlock_extent_cached(tree, delalloc_start, delalloc_end,
1317 &cached_state, GFP_NOFS);
Chris Masonc8b97812008-10-29 14:49:59 -04001318 __unlock_for_delalloc(inode, locked_page,
1319 delalloc_start, delalloc_end);
1320 cond_resched();
1321 goto again;
1322 }
Chris Mason9655d292009-09-02 15:22:30 -04001323 free_extent_state(cached_state);
Chris Masonc8b97812008-10-29 14:49:59 -04001324 *start = delalloc_start;
1325 *end = delalloc_end;
1326out_failed:
1327 return found;
1328}
1329
1330int extent_clear_unlock_delalloc(struct inode *inode,
1331 struct extent_io_tree *tree,
1332 u64 start, u64 end, struct page *locked_page,
Chris Masona791e352009-10-08 11:27:10 -04001333 unsigned long op)
Chris Masonc8b97812008-10-29 14:49:59 -04001334{
1335 int ret;
1336 struct page *pages[16];
1337 unsigned long index = start >> PAGE_CACHE_SHIFT;
1338 unsigned long end_index = end >> PAGE_CACHE_SHIFT;
1339 unsigned long nr_pages = end_index - index + 1;
1340 int i;
Chris Mason771ed682008-11-06 22:02:51 -05001341 int clear_bits = 0;
Chris Masonc8b97812008-10-29 14:49:59 -04001342
Chris Masona791e352009-10-08 11:27:10 -04001343 if (op & EXTENT_CLEAR_UNLOCK)
Chris Mason771ed682008-11-06 22:02:51 -05001344 clear_bits |= EXTENT_LOCKED;
Chris Masona791e352009-10-08 11:27:10 -04001345 if (op & EXTENT_CLEAR_DIRTY)
Chris Masonc8b97812008-10-29 14:49:59 -04001346 clear_bits |= EXTENT_DIRTY;
1347
Chris Masona791e352009-10-08 11:27:10 -04001348 if (op & EXTENT_CLEAR_DELALLOC)
Chris Mason771ed682008-11-06 22:02:51 -05001349 clear_bits |= EXTENT_DELALLOC;
1350
Chris Mason2c64c532009-09-02 15:04:12 -04001351 clear_extent_bit(tree, start, end, clear_bits, 1, 0, NULL, GFP_NOFS);
Josef Bacik32c00af2009-10-08 13:34:05 -04001352 if (!(op & (EXTENT_CLEAR_UNLOCK_PAGE | EXTENT_CLEAR_DIRTY |
1353 EXTENT_SET_WRITEBACK | EXTENT_END_WRITEBACK |
1354 EXTENT_SET_PRIVATE2)))
Chris Mason771ed682008-11-06 22:02:51 -05001355 return 0;
Chris Masonc8b97812008-10-29 14:49:59 -04001356
Chris Masond3977122009-01-05 21:25:51 -05001357 while (nr_pages > 0) {
Chris Masonc8b97812008-10-29 14:49:59 -04001358 ret = find_get_pages_contig(inode->i_mapping, index,
Chris Mason5b050f02008-11-11 09:34:41 -05001359 min_t(unsigned long,
1360 nr_pages, ARRAY_SIZE(pages)), pages);
Chris Masonc8b97812008-10-29 14:49:59 -04001361 for (i = 0; i < ret; i++) {
Chris Mason8b62b722009-09-02 16:53:46 -04001362
Chris Masona791e352009-10-08 11:27:10 -04001363 if (op & EXTENT_SET_PRIVATE2)
Chris Mason8b62b722009-09-02 16:53:46 -04001364 SetPagePrivate2(pages[i]);
1365
Chris Masonc8b97812008-10-29 14:49:59 -04001366 if (pages[i] == locked_page) {
1367 page_cache_release(pages[i]);
1368 continue;
1369 }
Chris Masona791e352009-10-08 11:27:10 -04001370 if (op & EXTENT_CLEAR_DIRTY)
Chris Masonc8b97812008-10-29 14:49:59 -04001371 clear_page_dirty_for_io(pages[i]);
Chris Masona791e352009-10-08 11:27:10 -04001372 if (op & EXTENT_SET_WRITEBACK)
Chris Masonc8b97812008-10-29 14:49:59 -04001373 set_page_writeback(pages[i]);
Chris Masona791e352009-10-08 11:27:10 -04001374 if (op & EXTENT_END_WRITEBACK)
Chris Masonc8b97812008-10-29 14:49:59 -04001375 end_page_writeback(pages[i]);
Chris Masona791e352009-10-08 11:27:10 -04001376 if (op & EXTENT_CLEAR_UNLOCK_PAGE)
Chris Mason771ed682008-11-06 22:02:51 -05001377 unlock_page(pages[i]);
Chris Masonc8b97812008-10-29 14:49:59 -04001378 page_cache_release(pages[i]);
1379 }
1380 nr_pages -= ret;
1381 index += ret;
1382 cond_resched();
1383 }
1384 return 0;
1385}
Chris Masonc8b97812008-10-29 14:49:59 -04001386
Chris Masond352ac62008-09-29 15:18:18 -04001387/*
1388 * count the number of bytes in the tree that have a given bit(s)
1389 * set. This can be fairly slow, except for EXTENT_DIRTY which is
1390 * cached. The total number found is returned.
1391 */
Chris Masond1310b22008-01-24 16:13:08 -05001392u64 count_range_bits(struct extent_io_tree *tree,
1393 u64 *start, u64 search_end, u64 max_bytes,
Chris Masonec29ed52011-02-23 16:23:20 -05001394 unsigned long bits, int contig)
Chris Masond1310b22008-01-24 16:13:08 -05001395{
1396 struct rb_node *node;
1397 struct extent_state *state;
1398 u64 cur_start = *start;
1399 u64 total_bytes = 0;
Chris Masonec29ed52011-02-23 16:23:20 -05001400 u64 last = 0;
Chris Masond1310b22008-01-24 16:13:08 -05001401 int found = 0;
1402
1403 if (search_end <= cur_start) {
Chris Masond1310b22008-01-24 16:13:08 -05001404 WARN_ON(1);
1405 return 0;
1406 }
1407
Chris Masoncad321a2008-12-17 14:51:42 -05001408 spin_lock(&tree->lock);
Chris Masond1310b22008-01-24 16:13:08 -05001409 if (cur_start == 0 && bits == EXTENT_DIRTY) {
1410 total_bytes = tree->dirty_bytes;
1411 goto out;
1412 }
1413 /*
1414 * this search will find all the extents that end after
1415 * our range starts.
1416 */
Chris Mason80ea96b2008-02-01 14:51:59 -05001417 node = tree_search(tree, cur_start);
Chris Masond3977122009-01-05 21:25:51 -05001418 if (!node)
Chris Masond1310b22008-01-24 16:13:08 -05001419 goto out;
Chris Masond1310b22008-01-24 16:13:08 -05001420
Chris Masond3977122009-01-05 21:25:51 -05001421 while (1) {
Chris Masond1310b22008-01-24 16:13:08 -05001422 state = rb_entry(node, struct extent_state, rb_node);
1423 if (state->start > search_end)
1424 break;
Chris Masonec29ed52011-02-23 16:23:20 -05001425 if (contig && found && state->start > last + 1)
1426 break;
1427 if (state->end >= cur_start && (state->state & bits) == bits) {
Chris Masond1310b22008-01-24 16:13:08 -05001428 total_bytes += min(search_end, state->end) + 1 -
1429 max(cur_start, state->start);
1430 if (total_bytes >= max_bytes)
1431 break;
1432 if (!found) {
Josef Bacikaf60bed2011-05-04 11:11:17 -04001433 *start = max(cur_start, state->start);
Chris Masond1310b22008-01-24 16:13:08 -05001434 found = 1;
1435 }
Chris Masonec29ed52011-02-23 16:23:20 -05001436 last = state->end;
1437 } else if (contig && found) {
1438 break;
Chris Masond1310b22008-01-24 16:13:08 -05001439 }
1440 node = rb_next(node);
1441 if (!node)
1442 break;
1443 }
1444out:
Chris Masoncad321a2008-12-17 14:51:42 -05001445 spin_unlock(&tree->lock);
Chris Masond1310b22008-01-24 16:13:08 -05001446 return total_bytes;
1447}
Christoph Hellwigb2950862008-12-02 09:54:17 -05001448
Chris Masond352ac62008-09-29 15:18:18 -04001449/*
1450 * set the private field for a given byte offset in the tree. If there isn't
1451 * an extent_state there already, this does nothing.
1452 */
Chris Masond1310b22008-01-24 16:13:08 -05001453int set_state_private(struct extent_io_tree *tree, u64 start, u64 private)
1454{
1455 struct rb_node *node;
1456 struct extent_state *state;
1457 int ret = 0;
1458
Chris Masoncad321a2008-12-17 14:51:42 -05001459 spin_lock(&tree->lock);
Chris Masond1310b22008-01-24 16:13:08 -05001460 /*
1461 * this search will find all the extents that end after
1462 * our range starts.
1463 */
Chris Mason80ea96b2008-02-01 14:51:59 -05001464 node = tree_search(tree, start);
Peter2b114d12008-04-01 11:21:40 -04001465 if (!node) {
Chris Masond1310b22008-01-24 16:13:08 -05001466 ret = -ENOENT;
1467 goto out;
1468 }
1469 state = rb_entry(node, struct extent_state, rb_node);
1470 if (state->start != start) {
1471 ret = -ENOENT;
1472 goto out;
1473 }
1474 state->private = private;
1475out:
Chris Masoncad321a2008-12-17 14:51:42 -05001476 spin_unlock(&tree->lock);
Chris Masond1310b22008-01-24 16:13:08 -05001477 return ret;
1478}
1479
1480int get_state_private(struct extent_io_tree *tree, u64 start, u64 *private)
1481{
1482 struct rb_node *node;
1483 struct extent_state *state;
1484 int ret = 0;
1485
Chris Masoncad321a2008-12-17 14:51:42 -05001486 spin_lock(&tree->lock);
Chris Masond1310b22008-01-24 16:13:08 -05001487 /*
1488 * this search will find all the extents that end after
1489 * our range starts.
1490 */
Chris Mason80ea96b2008-02-01 14:51:59 -05001491 node = tree_search(tree, start);
Peter2b114d12008-04-01 11:21:40 -04001492 if (!node) {
Chris Masond1310b22008-01-24 16:13:08 -05001493 ret = -ENOENT;
1494 goto out;
1495 }
1496 state = rb_entry(node, struct extent_state, rb_node);
1497 if (state->start != start) {
1498 ret = -ENOENT;
1499 goto out;
1500 }
1501 *private = state->private;
1502out:
Chris Masoncad321a2008-12-17 14:51:42 -05001503 spin_unlock(&tree->lock);
Chris Masond1310b22008-01-24 16:13:08 -05001504 return ret;
1505}
1506
1507/*
1508 * searches a range in the state tree for a given mask.
Chris Mason70dec802008-01-29 09:59:12 -05001509 * If 'filled' == 1, this returns 1 only if every extent in the tree
Chris Masond1310b22008-01-24 16:13:08 -05001510 * has the bits set. Otherwise, 1 is returned if any bit in the
1511 * range is found set.
1512 */
1513int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
Chris Mason9655d292009-09-02 15:22:30 -04001514 int bits, int filled, struct extent_state *cached)
Chris Masond1310b22008-01-24 16:13:08 -05001515{
1516 struct extent_state *state = NULL;
1517 struct rb_node *node;
1518 int bitset = 0;
Chris Masond1310b22008-01-24 16:13:08 -05001519
Chris Masoncad321a2008-12-17 14:51:42 -05001520 spin_lock(&tree->lock);
Josef Bacikdf98b6e2011-06-20 14:53:48 -04001521 if (cached && cached->tree && cached->start <= start &&
1522 cached->end > start)
Chris Mason9655d292009-09-02 15:22:30 -04001523 node = &cached->rb_node;
1524 else
1525 node = tree_search(tree, start);
Chris Masond1310b22008-01-24 16:13:08 -05001526 while (node && start <= end) {
1527 state = rb_entry(node, struct extent_state, rb_node);
1528
1529 if (filled && state->start > start) {
1530 bitset = 0;
1531 break;
1532 }
1533
1534 if (state->start > end)
1535 break;
1536
1537 if (state->state & bits) {
1538 bitset = 1;
1539 if (!filled)
1540 break;
1541 } else if (filled) {
1542 bitset = 0;
1543 break;
1544 }
Chris Mason46562cec2009-09-23 20:23:16 -04001545
1546 if (state->end == (u64)-1)
1547 break;
1548
Chris Masond1310b22008-01-24 16:13:08 -05001549 start = state->end + 1;
1550 if (start > end)
1551 break;
1552 node = rb_next(node);
1553 if (!node) {
1554 if (filled)
1555 bitset = 0;
1556 break;
1557 }
1558 }
Chris Masoncad321a2008-12-17 14:51:42 -05001559 spin_unlock(&tree->lock);
Chris Masond1310b22008-01-24 16:13:08 -05001560 return bitset;
1561}
Chris Masond1310b22008-01-24 16:13:08 -05001562
1563/*
1564 * helper function to set a given page up to date if all the
1565 * extents in the tree for that page are up to date
1566 */
1567static int check_page_uptodate(struct extent_io_tree *tree,
1568 struct page *page)
1569{
1570 u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
1571 u64 end = start + PAGE_CACHE_SIZE - 1;
Chris Mason9655d292009-09-02 15:22:30 -04001572 if (test_range_bit(tree, start, end, EXTENT_UPTODATE, 1, NULL))
Chris Masond1310b22008-01-24 16:13:08 -05001573 SetPageUptodate(page);
1574 return 0;
1575}
1576
1577/*
1578 * helper function to unlock a page if all the extents in the tree
1579 * for that page are unlocked
1580 */
1581static int check_page_locked(struct extent_io_tree *tree,
1582 struct page *page)
1583{
1584 u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
1585 u64 end = start + PAGE_CACHE_SIZE - 1;
Chris Mason9655d292009-09-02 15:22:30 -04001586 if (!test_range_bit(tree, start, end, EXTENT_LOCKED, 0, NULL))
Chris Masond1310b22008-01-24 16:13:08 -05001587 unlock_page(page);
1588 return 0;
1589}
1590
1591/*
1592 * helper function to end page writeback if all the extents
1593 * in the tree for that page are done with writeback
1594 */
1595static int check_page_writeback(struct extent_io_tree *tree,
1596 struct page *page)
1597{
Chris Mason1edbb732009-09-02 13:24:36 -04001598 end_page_writeback(page);
Chris Masond1310b22008-01-24 16:13:08 -05001599 return 0;
1600}
1601
1602/* lots and lots of room for performance fixes in the end_bio funcs */
1603
1604/*
1605 * after a writepage IO is done, we need to:
1606 * clear the uptodate bits on error
1607 * clear the writeback bits in the extent tree for this IO
1608 * end_page_writeback if the page has no more pending IO
1609 *
1610 * Scheduling is not allowed, so the extent state tree is expected
1611 * to have one and only one object corresponding to this IO.
1612 */
Chris Masond1310b22008-01-24 16:13:08 -05001613static void end_bio_extent_writepage(struct bio *bio, int err)
Chris Masond1310b22008-01-24 16:13:08 -05001614{
Chris Mason1259ab72008-05-12 13:39:03 -04001615 int uptodate = err == 0;
Chris Masond1310b22008-01-24 16:13:08 -05001616 struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;
David Woodhouse902b22f2008-08-20 08:51:49 -04001617 struct extent_io_tree *tree;
Chris Masond1310b22008-01-24 16:13:08 -05001618 u64 start;
1619 u64 end;
1620 int whole_page;
Chris Mason1259ab72008-05-12 13:39:03 -04001621 int ret;
Chris Masond1310b22008-01-24 16:13:08 -05001622
Chris Masond1310b22008-01-24 16:13:08 -05001623 do {
1624 struct page *page = bvec->bv_page;
David Woodhouse902b22f2008-08-20 08:51:49 -04001625 tree = &BTRFS_I(page->mapping->host)->io_tree;
1626
Chris Masond1310b22008-01-24 16:13:08 -05001627 start = ((u64)page->index << PAGE_CACHE_SHIFT) +
1628 bvec->bv_offset;
1629 end = start + bvec->bv_len - 1;
1630
1631 if (bvec->bv_offset == 0 && bvec->bv_len == PAGE_CACHE_SIZE)
1632 whole_page = 1;
1633 else
1634 whole_page = 0;
1635
1636 if (--bvec >= bio->bi_io_vec)
1637 prefetchw(&bvec->bv_page->flags);
Chris Mason1259ab72008-05-12 13:39:03 -04001638 if (tree->ops && tree->ops->writepage_end_io_hook) {
1639 ret = tree->ops->writepage_end_io_hook(page, start,
David Woodhouse902b22f2008-08-20 08:51:49 -04001640 end, NULL, uptodate);
Chris Mason1259ab72008-05-12 13:39:03 -04001641 if (ret)
1642 uptodate = 0;
1643 }
1644
1645 if (!uptodate && tree->ops &&
1646 tree->ops->writepage_io_failed_hook) {
1647 ret = tree->ops->writepage_io_failed_hook(bio, page,
David Woodhouse902b22f2008-08-20 08:51:49 -04001648 start, end, NULL);
Chris Mason1259ab72008-05-12 13:39:03 -04001649 if (ret == 0) {
Chris Mason1259ab72008-05-12 13:39:03 -04001650 uptodate = (err == 0);
1651 continue;
1652 }
1653 }
1654
Chris Masond1310b22008-01-24 16:13:08 -05001655 if (!uptodate) {
Josef Bacik2ac55d42010-02-03 19:33:23 +00001656 clear_extent_uptodate(tree, start, end, NULL, GFP_NOFS);
Chris Masond1310b22008-01-24 16:13:08 -05001657 ClearPageUptodate(page);
1658 SetPageError(page);
1659 }
Chris Mason70dec802008-01-29 09:59:12 -05001660
Chris Masond1310b22008-01-24 16:13:08 -05001661 if (whole_page)
1662 end_page_writeback(page);
1663 else
1664 check_page_writeback(tree, page);
Chris Masond1310b22008-01-24 16:13:08 -05001665 } while (bvec >= bio->bi_io_vec);
Chris Mason2b1f55b2008-09-24 11:48:04 -04001666
Chris Masond1310b22008-01-24 16:13:08 -05001667 bio_put(bio);
Chris Masond1310b22008-01-24 16:13:08 -05001668}
1669
1670/*
1671 * after a readpage IO is done, we need to:
1672 * clear the uptodate bits on error
1673 * set the uptodate bits if things worked
1674 * set the page up to date if all extents in the tree are uptodate
1675 * clear the lock bit in the extent tree
1676 * unlock the page if there are no other extents locked for it
1677 *
1678 * Scheduling is not allowed, so the extent state tree is expected
1679 * to have one and only one object corresponding to this IO.
1680 */
Chris Masond1310b22008-01-24 16:13:08 -05001681static void end_bio_extent_readpage(struct bio *bio, int err)
Chris Masond1310b22008-01-24 16:13:08 -05001682{
1683 int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
Chris Mason4125bf72010-02-03 18:18:45 +00001684 struct bio_vec *bvec_end = bio->bi_io_vec + bio->bi_vcnt - 1;
1685 struct bio_vec *bvec = bio->bi_io_vec;
David Woodhouse902b22f2008-08-20 08:51:49 -04001686 struct extent_io_tree *tree;
Chris Masond1310b22008-01-24 16:13:08 -05001687 u64 start;
1688 u64 end;
1689 int whole_page;
1690 int ret;
1691
Chris Masond20f7042008-12-08 16:58:54 -05001692 if (err)
1693 uptodate = 0;
1694
Chris Masond1310b22008-01-24 16:13:08 -05001695 do {
1696 struct page *page = bvec->bv_page;
Arne Jansen507903b2011-04-06 10:02:20 +00001697 struct extent_state *cached = NULL;
1698 struct extent_state *state;
1699
David Woodhouse902b22f2008-08-20 08:51:49 -04001700 tree = &BTRFS_I(page->mapping->host)->io_tree;
1701
Chris Masond1310b22008-01-24 16:13:08 -05001702 start = ((u64)page->index << PAGE_CACHE_SHIFT) +
1703 bvec->bv_offset;
1704 end = start + bvec->bv_len - 1;
1705
1706 if (bvec->bv_offset == 0 && bvec->bv_len == PAGE_CACHE_SIZE)
1707 whole_page = 1;
1708 else
1709 whole_page = 0;
1710
Chris Mason4125bf72010-02-03 18:18:45 +00001711 if (++bvec <= bvec_end)
Chris Masond1310b22008-01-24 16:13:08 -05001712 prefetchw(&bvec->bv_page->flags);
1713
Arne Jansen507903b2011-04-06 10:02:20 +00001714 spin_lock(&tree->lock);
Chris Mason0d399202011-04-16 06:55:39 -04001715 state = find_first_extent_bit_state(tree, start, EXTENT_LOCKED);
Chris Mason109b36a2011-04-12 13:57:39 -04001716 if (state && state->start == start) {
Arne Jansen507903b2011-04-06 10:02:20 +00001717 /*
1718 * take a reference on the state, unlock will drop
1719 * the ref
1720 */
1721 cache_state(state, &cached);
1722 }
1723 spin_unlock(&tree->lock);
1724
Chris Masond1310b22008-01-24 16:13:08 -05001725 if (uptodate && tree->ops && tree->ops->readpage_end_io_hook) {
Chris Mason70dec802008-01-29 09:59:12 -05001726 ret = tree->ops->readpage_end_io_hook(page, start, end,
Arne Jansen507903b2011-04-06 10:02:20 +00001727 state);
Chris Masond1310b22008-01-24 16:13:08 -05001728 if (ret)
1729 uptodate = 0;
1730 }
Chris Mason7e383262008-04-09 16:28:12 -04001731 if (!uptodate && tree->ops &&
1732 tree->ops->readpage_io_failed_hook) {
1733 ret = tree->ops->readpage_io_failed_hook(bio, page,
David Woodhouse902b22f2008-08-20 08:51:49 -04001734 start, end, NULL);
Chris Mason7e383262008-04-09 16:28:12 -04001735 if (ret == 0) {
Chris Mason3b951512008-04-17 11:29:12 -04001736 uptodate =
1737 test_bit(BIO_UPTODATE, &bio->bi_flags);
Chris Masond20f7042008-12-08 16:58:54 -05001738 if (err)
1739 uptodate = 0;
Arne Jansen507903b2011-04-06 10:02:20 +00001740 uncache_state(&cached);
Chris Mason7e383262008-04-09 16:28:12 -04001741 continue;
1742 }
1743 }
Chris Mason70dec802008-01-29 09:59:12 -05001744
Chris Mason771ed682008-11-06 22:02:51 -05001745 if (uptodate) {
Arne Jansen507903b2011-04-06 10:02:20 +00001746 set_extent_uptodate(tree, start, end, &cached,
David Woodhouse902b22f2008-08-20 08:51:49 -04001747 GFP_ATOMIC);
Chris Mason771ed682008-11-06 22:02:51 -05001748 }
Arne Jansen507903b2011-04-06 10:02:20 +00001749 unlock_extent_cached(tree, start, end, &cached, GFP_ATOMIC);
Chris Masond1310b22008-01-24 16:13:08 -05001750
Chris Mason70dec802008-01-29 09:59:12 -05001751 if (whole_page) {
1752 if (uptodate) {
1753 SetPageUptodate(page);
1754 } else {
1755 ClearPageUptodate(page);
1756 SetPageError(page);
1757 }
Chris Masond1310b22008-01-24 16:13:08 -05001758 unlock_page(page);
Chris Mason70dec802008-01-29 09:59:12 -05001759 } else {
1760 if (uptodate) {
1761 check_page_uptodate(tree, page);
1762 } else {
1763 ClearPageUptodate(page);
1764 SetPageError(page);
1765 }
Chris Masond1310b22008-01-24 16:13:08 -05001766 check_page_locked(tree, page);
Chris Mason70dec802008-01-29 09:59:12 -05001767 }
Chris Mason4125bf72010-02-03 18:18:45 +00001768 } while (bvec <= bvec_end);
Chris Masond1310b22008-01-24 16:13:08 -05001769
1770 bio_put(bio);
Chris Masond1310b22008-01-24 16:13:08 -05001771}
1772
Miao Xie88f794e2010-11-22 03:02:55 +00001773struct bio *
1774btrfs_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs,
1775 gfp_t gfp_flags)
Chris Masond1310b22008-01-24 16:13:08 -05001776{
1777 struct bio *bio;
1778
1779 bio = bio_alloc(gfp_flags, nr_vecs);
1780
1781 if (bio == NULL && (current->flags & PF_MEMALLOC)) {
1782 while (!bio && (nr_vecs /= 2))
1783 bio = bio_alloc(gfp_flags, nr_vecs);
1784 }
1785
1786 if (bio) {
Chris Masone1c4b742008-04-22 13:26:46 -04001787 bio->bi_size = 0;
Chris Masond1310b22008-01-24 16:13:08 -05001788 bio->bi_bdev = bdev;
1789 bio->bi_sector = first_sector;
1790 }
1791 return bio;
1792}
1793
Chris Masonc8b97812008-10-29 14:49:59 -04001794static int submit_one_bio(int rw, struct bio *bio, int mirror_num,
1795 unsigned long bio_flags)
Chris Masond1310b22008-01-24 16:13:08 -05001796{
Chris Masond1310b22008-01-24 16:13:08 -05001797 int ret = 0;
Chris Mason70dec802008-01-29 09:59:12 -05001798 struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;
1799 struct page *page = bvec->bv_page;
1800 struct extent_io_tree *tree = bio->bi_private;
Chris Mason70dec802008-01-29 09:59:12 -05001801 u64 start;
Chris Mason70dec802008-01-29 09:59:12 -05001802
1803 start = ((u64)page->index << PAGE_CACHE_SHIFT) + bvec->bv_offset;
Chris Mason70dec802008-01-29 09:59:12 -05001804
David Woodhouse902b22f2008-08-20 08:51:49 -04001805 bio->bi_private = NULL;
Chris Masond1310b22008-01-24 16:13:08 -05001806
1807 bio_get(bio);
1808
Chris Mason065631f2008-02-20 12:07:25 -05001809 if (tree->ops && tree->ops->submit_bio_hook)
liubo6b82ce82011-01-26 06:21:39 +00001810 ret = tree->ops->submit_bio_hook(page->mapping->host, rw, bio,
Chris Masoneaf25d92010-05-25 09:48:28 -04001811 mirror_num, bio_flags, start);
Chris Mason0b86a832008-03-24 15:01:56 -04001812 else
1813 submit_bio(rw, bio);
Chris Masond1310b22008-01-24 16:13:08 -05001814 if (bio_flagged(bio, BIO_EOPNOTSUPP))
1815 ret = -EOPNOTSUPP;
1816 bio_put(bio);
1817 return ret;
1818}
1819
1820static int submit_extent_page(int rw, struct extent_io_tree *tree,
1821 struct page *page, sector_t sector,
1822 size_t size, unsigned long offset,
1823 struct block_device *bdev,
1824 struct bio **bio_ret,
1825 unsigned long max_pages,
Chris Masonf1885912008-04-09 16:28:12 -04001826 bio_end_io_t end_io_func,
Chris Masonc8b97812008-10-29 14:49:59 -04001827 int mirror_num,
1828 unsigned long prev_bio_flags,
1829 unsigned long bio_flags)
Chris Masond1310b22008-01-24 16:13:08 -05001830{
1831 int ret = 0;
1832 struct bio *bio;
1833 int nr;
Chris Masonc8b97812008-10-29 14:49:59 -04001834 int contig = 0;
1835 int this_compressed = bio_flags & EXTENT_BIO_COMPRESSED;
1836 int old_compressed = prev_bio_flags & EXTENT_BIO_COMPRESSED;
Chris Mason5b050f02008-11-11 09:34:41 -05001837 size_t page_size = min_t(size_t, size, PAGE_CACHE_SIZE);
Chris Masond1310b22008-01-24 16:13:08 -05001838
1839 if (bio_ret && *bio_ret) {
1840 bio = *bio_ret;
Chris Masonc8b97812008-10-29 14:49:59 -04001841 if (old_compressed)
1842 contig = bio->bi_sector == sector;
1843 else
1844 contig = bio->bi_sector + (bio->bi_size >> 9) ==
1845 sector;
1846
1847 if (prev_bio_flags != bio_flags || !contig ||
Chris Mason239b14b2008-03-24 15:02:07 -04001848 (tree->ops && tree->ops->merge_bio_hook &&
Chris Masonc8b97812008-10-29 14:49:59 -04001849 tree->ops->merge_bio_hook(page, offset, page_size, bio,
1850 bio_flags)) ||
1851 bio_add_page(bio, page, page_size, offset) < page_size) {
1852 ret = submit_one_bio(rw, bio, mirror_num,
1853 prev_bio_flags);
Chris Masond1310b22008-01-24 16:13:08 -05001854 bio = NULL;
1855 } else {
1856 return 0;
1857 }
1858 }
Chris Masonc8b97812008-10-29 14:49:59 -04001859 if (this_compressed)
1860 nr = BIO_MAX_PAGES;
1861 else
1862 nr = bio_get_nr_vecs(bdev);
1863
Miao Xie88f794e2010-11-22 03:02:55 +00001864 bio = btrfs_bio_alloc(bdev, sector, nr, GFP_NOFS | __GFP_HIGH);
Tsutomu Itoh5df67082011-02-01 09:17:35 +00001865 if (!bio)
1866 return -ENOMEM;
Chris Mason70dec802008-01-29 09:59:12 -05001867
Chris Masonc8b97812008-10-29 14:49:59 -04001868 bio_add_page(bio, page, page_size, offset);
Chris Masond1310b22008-01-24 16:13:08 -05001869 bio->bi_end_io = end_io_func;
1870 bio->bi_private = tree;
Chris Mason70dec802008-01-29 09:59:12 -05001871
Chris Masond3977122009-01-05 21:25:51 -05001872 if (bio_ret)
Chris Masond1310b22008-01-24 16:13:08 -05001873 *bio_ret = bio;
Chris Masond3977122009-01-05 21:25:51 -05001874 else
Chris Masonc8b97812008-10-29 14:49:59 -04001875 ret = submit_one_bio(rw, bio, mirror_num, bio_flags);
Chris Masond1310b22008-01-24 16:13:08 -05001876
1877 return ret;
1878}
1879
1880void set_page_extent_mapped(struct page *page)
1881{
1882 if (!PagePrivate(page)) {
1883 SetPagePrivate(page);
Chris Masond1310b22008-01-24 16:13:08 -05001884 page_cache_get(page);
Chris Mason6af118ce2008-07-22 11:18:07 -04001885 set_page_private(page, EXTENT_PAGE_PRIVATE);
Chris Masond1310b22008-01-24 16:13:08 -05001886 }
1887}
1888
Christoph Hellwigb2950862008-12-02 09:54:17 -05001889static void set_page_extent_head(struct page *page, unsigned long len)
Chris Masond1310b22008-01-24 16:13:08 -05001890{
Chris Masoneb14ab82011-02-10 12:35:00 -05001891 WARN_ON(!PagePrivate(page));
Chris Masond1310b22008-01-24 16:13:08 -05001892 set_page_private(page, EXTENT_PAGE_PRIVATE_FIRST_PAGE | len << 2);
1893}
1894
1895/*
1896 * basic readpage implementation. Locked extent state structs are inserted
1897 * into the tree that are removed when the IO is done (by the end_io
1898 * handlers)
1899 */
1900static int __extent_read_full_page(struct extent_io_tree *tree,
1901 struct page *page,
1902 get_extent_t *get_extent,
Chris Masonc8b97812008-10-29 14:49:59 -04001903 struct bio **bio, int mirror_num,
1904 unsigned long *bio_flags)
Chris Masond1310b22008-01-24 16:13:08 -05001905{
1906 struct inode *inode = page->mapping->host;
1907 u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
1908 u64 page_end = start + PAGE_CACHE_SIZE - 1;
1909 u64 end;
1910 u64 cur = start;
1911 u64 extent_offset;
1912 u64 last_byte = i_size_read(inode);
1913 u64 block_start;
1914 u64 cur_end;
1915 sector_t sector;
1916 struct extent_map *em;
1917 struct block_device *bdev;
Josef Bacik11c65dc2010-05-23 11:07:21 -04001918 struct btrfs_ordered_extent *ordered;
Chris Masond1310b22008-01-24 16:13:08 -05001919 int ret;
1920 int nr = 0;
David Sterba306e16c2011-04-19 14:29:38 +02001921 size_t pg_offset = 0;
Chris Masond1310b22008-01-24 16:13:08 -05001922 size_t iosize;
Chris Masonc8b97812008-10-29 14:49:59 -04001923 size_t disk_io_size;
Chris Masond1310b22008-01-24 16:13:08 -05001924 size_t blocksize = inode->i_sb->s_blocksize;
Chris Masonc8b97812008-10-29 14:49:59 -04001925 unsigned long this_bio_flag = 0;
Chris Masond1310b22008-01-24 16:13:08 -05001926
1927 set_page_extent_mapped(page);
1928
Dan Magenheimer90a887c2011-05-26 10:01:56 -06001929 if (!PageUptodate(page)) {
1930 if (cleancache_get_page(page) == 0) {
1931 BUG_ON(blocksize != PAGE_SIZE);
1932 goto out;
1933 }
1934 }
1935
Chris Masond1310b22008-01-24 16:13:08 -05001936 end = page_end;
Josef Bacik11c65dc2010-05-23 11:07:21 -04001937 while (1) {
1938 lock_extent(tree, start, end, GFP_NOFS);
1939 ordered = btrfs_lookup_ordered_extent(inode, start);
1940 if (!ordered)
1941 break;
1942 unlock_extent(tree, start, end, GFP_NOFS);
1943 btrfs_start_ordered_extent(inode, ordered, 1);
1944 btrfs_put_ordered_extent(ordered);
1945 }
Chris Masond1310b22008-01-24 16:13:08 -05001946
Chris Masonc8b97812008-10-29 14:49:59 -04001947 if (page->index == last_byte >> PAGE_CACHE_SHIFT) {
1948 char *userpage;
1949 size_t zero_offset = last_byte & (PAGE_CACHE_SIZE - 1);
1950
1951 if (zero_offset) {
1952 iosize = PAGE_CACHE_SIZE - zero_offset;
1953 userpage = kmap_atomic(page, KM_USER0);
1954 memset(userpage + zero_offset, 0, iosize);
1955 flush_dcache_page(page);
1956 kunmap_atomic(userpage, KM_USER0);
1957 }
1958 }
Chris Masond1310b22008-01-24 16:13:08 -05001959 while (cur <= end) {
1960 if (cur >= last_byte) {
1961 char *userpage;
Arne Jansen507903b2011-04-06 10:02:20 +00001962 struct extent_state *cached = NULL;
1963
David Sterba306e16c2011-04-19 14:29:38 +02001964 iosize = PAGE_CACHE_SIZE - pg_offset;
Chris Masond1310b22008-01-24 16:13:08 -05001965 userpage = kmap_atomic(page, KM_USER0);
David Sterba306e16c2011-04-19 14:29:38 +02001966 memset(userpage + pg_offset, 0, iosize);
Chris Masond1310b22008-01-24 16:13:08 -05001967 flush_dcache_page(page);
1968 kunmap_atomic(userpage, KM_USER0);
1969 set_extent_uptodate(tree, cur, cur + iosize - 1,
Arne Jansen507903b2011-04-06 10:02:20 +00001970 &cached, GFP_NOFS);
1971 unlock_extent_cached(tree, cur, cur + iosize - 1,
1972 &cached, GFP_NOFS);
Chris Masond1310b22008-01-24 16:13:08 -05001973 break;
1974 }
David Sterba306e16c2011-04-19 14:29:38 +02001975 em = get_extent(inode, page, pg_offset, cur,
Chris Masond1310b22008-01-24 16:13:08 -05001976 end - cur + 1, 0);
David Sterbac7040052011-04-19 18:00:01 +02001977 if (IS_ERR_OR_NULL(em)) {
Chris Masond1310b22008-01-24 16:13:08 -05001978 SetPageError(page);
1979 unlock_extent(tree, cur, end, GFP_NOFS);
1980 break;
1981 }
Chris Masond1310b22008-01-24 16:13:08 -05001982 extent_offset = cur - em->start;
1983 BUG_ON(extent_map_end(em) <= cur);
1984 BUG_ON(end < cur);
1985
Li Zefan261507a02010-12-17 14:21:50 +08001986 if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
Chris Masonc8b97812008-10-29 14:49:59 -04001987 this_bio_flag = EXTENT_BIO_COMPRESSED;
Li Zefan261507a02010-12-17 14:21:50 +08001988 extent_set_compress_type(&this_bio_flag,
1989 em->compress_type);
1990 }
Chris Masonc8b97812008-10-29 14:49:59 -04001991
Chris Masond1310b22008-01-24 16:13:08 -05001992 iosize = min(extent_map_end(em) - cur, end - cur + 1);
1993 cur_end = min(extent_map_end(em) - 1, end);
1994 iosize = (iosize + blocksize - 1) & ~((u64)blocksize - 1);
Chris Masonc8b97812008-10-29 14:49:59 -04001995 if (this_bio_flag & EXTENT_BIO_COMPRESSED) {
1996 disk_io_size = em->block_len;
1997 sector = em->block_start >> 9;
1998 } else {
1999 sector = (em->block_start + extent_offset) >> 9;
2000 disk_io_size = iosize;
2001 }
Chris Masond1310b22008-01-24 16:13:08 -05002002 bdev = em->bdev;
2003 block_start = em->block_start;
Yan Zhengd899e052008-10-30 14:25:28 -04002004 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
2005 block_start = EXTENT_MAP_HOLE;
Chris Masond1310b22008-01-24 16:13:08 -05002006 free_extent_map(em);
2007 em = NULL;
2008
2009 /* we've found a hole, just zero and go on */
2010 if (block_start == EXTENT_MAP_HOLE) {
2011 char *userpage;
Arne Jansen507903b2011-04-06 10:02:20 +00002012 struct extent_state *cached = NULL;
2013
Chris Masond1310b22008-01-24 16:13:08 -05002014 userpage = kmap_atomic(page, KM_USER0);
David Sterba306e16c2011-04-19 14:29:38 +02002015 memset(userpage + pg_offset, 0, iosize);
Chris Masond1310b22008-01-24 16:13:08 -05002016 flush_dcache_page(page);
2017 kunmap_atomic(userpage, KM_USER0);
2018
2019 set_extent_uptodate(tree, cur, cur + iosize - 1,
Arne Jansen507903b2011-04-06 10:02:20 +00002020 &cached, GFP_NOFS);
2021 unlock_extent_cached(tree, cur, cur + iosize - 1,
2022 &cached, GFP_NOFS);
Chris Masond1310b22008-01-24 16:13:08 -05002023 cur = cur + iosize;
David Sterba306e16c2011-04-19 14:29:38 +02002024 pg_offset += iosize;
Chris Masond1310b22008-01-24 16:13:08 -05002025 continue;
2026 }
2027 /* the get_extent function already copied into the page */
Chris Mason9655d292009-09-02 15:22:30 -04002028 if (test_range_bit(tree, cur, cur_end,
2029 EXTENT_UPTODATE, 1, NULL)) {
Chris Masona1b32a52008-09-05 16:09:51 -04002030 check_page_uptodate(tree, page);
Chris Masond1310b22008-01-24 16:13:08 -05002031 unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS);
2032 cur = cur + iosize;
David Sterba306e16c2011-04-19 14:29:38 +02002033 pg_offset += iosize;
Chris Masond1310b22008-01-24 16:13:08 -05002034 continue;
2035 }
Chris Mason70dec802008-01-29 09:59:12 -05002036 /* we have an inline extent but it didn't get marked up
2037 * to date. Error out
2038 */
2039 if (block_start == EXTENT_MAP_INLINE) {
2040 SetPageError(page);
2041 unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS);
2042 cur = cur + iosize;
David Sterba306e16c2011-04-19 14:29:38 +02002043 pg_offset += iosize;
Chris Mason70dec802008-01-29 09:59:12 -05002044 continue;
2045 }
Chris Masond1310b22008-01-24 16:13:08 -05002046
2047 ret = 0;
2048 if (tree->ops && tree->ops->readpage_io_hook) {
2049 ret = tree->ops->readpage_io_hook(page, cur,
2050 cur + iosize - 1);
2051 }
2052 if (!ret) {
Chris Mason89642222008-07-24 09:41:53 -04002053 unsigned long pnr = (last_byte >> PAGE_CACHE_SHIFT) + 1;
2054 pnr -= page->index;
Chris Masond1310b22008-01-24 16:13:08 -05002055 ret = submit_extent_page(READ, tree, page,
David Sterba306e16c2011-04-19 14:29:38 +02002056 sector, disk_io_size, pg_offset,
Chris Mason89642222008-07-24 09:41:53 -04002057 bdev, bio, pnr,
Chris Masonc8b97812008-10-29 14:49:59 -04002058 end_bio_extent_readpage, mirror_num,
2059 *bio_flags,
2060 this_bio_flag);
Chris Mason89642222008-07-24 09:41:53 -04002061 nr++;
Chris Masonc8b97812008-10-29 14:49:59 -04002062 *bio_flags = this_bio_flag;
Chris Masond1310b22008-01-24 16:13:08 -05002063 }
2064 if (ret)
2065 SetPageError(page);
2066 cur = cur + iosize;
David Sterba306e16c2011-04-19 14:29:38 +02002067 pg_offset += iosize;
Chris Masond1310b22008-01-24 16:13:08 -05002068 }
Dan Magenheimer90a887c2011-05-26 10:01:56 -06002069out:
Chris Masond1310b22008-01-24 16:13:08 -05002070 if (!nr) {
2071 if (!PageError(page))
2072 SetPageUptodate(page);
2073 unlock_page(page);
2074 }
2075 return 0;
2076}
2077
2078int extent_read_full_page(struct extent_io_tree *tree, struct page *page,
2079 get_extent_t *get_extent)
2080{
2081 struct bio *bio = NULL;
Chris Masonc8b97812008-10-29 14:49:59 -04002082 unsigned long bio_flags = 0;
Chris Masond1310b22008-01-24 16:13:08 -05002083 int ret;
2084
Chris Masonc8b97812008-10-29 14:49:59 -04002085 ret = __extent_read_full_page(tree, page, get_extent, &bio, 0,
2086 &bio_flags);
Chris Masond1310b22008-01-24 16:13:08 -05002087 if (bio)
liubo6b82ce82011-01-26 06:21:39 +00002088 ret = submit_one_bio(READ, bio, 0, bio_flags);
Chris Masond1310b22008-01-24 16:13:08 -05002089 return ret;
2090}
Chris Masond1310b22008-01-24 16:13:08 -05002091
Chris Mason11c83492009-04-20 15:50:09 -04002092static noinline void update_nr_written(struct page *page,
2093 struct writeback_control *wbc,
2094 unsigned long nr_written)
2095{
2096 wbc->nr_to_write -= nr_written;
2097 if (wbc->range_cyclic || (wbc->nr_to_write > 0 &&
2098 wbc->range_start == 0 && wbc->range_end == LLONG_MAX))
2099 page->mapping->writeback_index = page->index + nr_written;
2100}
2101
Chris Masond1310b22008-01-24 16:13:08 -05002102/*
2103 * the writepage semantics are similar to regular writepage. extent
2104 * records are inserted to lock ranges in the tree, and as dirty areas
2105 * are found, they are marked writeback. Then the lock bits are removed
2106 * and the end_io handler clears the writeback ranges
2107 */
2108static int __extent_writepage(struct page *page, struct writeback_control *wbc,
2109 void *data)
2110{
2111 struct inode *inode = page->mapping->host;
2112 struct extent_page_data *epd = data;
2113 struct extent_io_tree *tree = epd->tree;
2114 u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
2115 u64 delalloc_start;
2116 u64 page_end = start + PAGE_CACHE_SIZE - 1;
2117 u64 end;
2118 u64 cur = start;
2119 u64 extent_offset;
2120 u64 last_byte = i_size_read(inode);
2121 u64 block_start;
2122 u64 iosize;
2123 sector_t sector;
Chris Mason2c64c532009-09-02 15:04:12 -04002124 struct extent_state *cached_state = NULL;
Chris Masond1310b22008-01-24 16:13:08 -05002125 struct extent_map *em;
2126 struct block_device *bdev;
2127 int ret;
2128 int nr = 0;
Chris Mason7f3c74f2008-07-18 12:01:11 -04002129 size_t pg_offset = 0;
Chris Masond1310b22008-01-24 16:13:08 -05002130 size_t blocksize;
2131 loff_t i_size = i_size_read(inode);
2132 unsigned long end_index = i_size >> PAGE_CACHE_SHIFT;
2133 u64 nr_delalloc;
2134 u64 delalloc_end;
Chris Masonc8b97812008-10-29 14:49:59 -04002135 int page_started;
2136 int compressed;
Chris Masonffbd5172009-04-20 15:50:09 -04002137 int write_flags;
Chris Mason771ed682008-11-06 22:02:51 -05002138 unsigned long nr_written = 0;
Chris Masond1310b22008-01-24 16:13:08 -05002139
Chris Masonffbd5172009-04-20 15:50:09 -04002140 if (wbc->sync_mode == WB_SYNC_ALL)
Jens Axboe721a9602011-03-09 11:56:30 +01002141 write_flags = WRITE_SYNC;
Chris Masonffbd5172009-04-20 15:50:09 -04002142 else
2143 write_flags = WRITE;
2144
liubo1abe9b82011-03-24 11:18:59 +00002145 trace___extent_writepage(page, inode, wbc);
2146
Chris Masond1310b22008-01-24 16:13:08 -05002147 WARN_ON(!PageLocked(page));
Chris Mason7f3c74f2008-07-18 12:01:11 -04002148 pg_offset = i_size & (PAGE_CACHE_SIZE - 1);
Chris Mason211c17f2008-05-15 09:13:45 -04002149 if (page->index > end_index ||
Chris Mason7f3c74f2008-07-18 12:01:11 -04002150 (page->index == end_index && !pg_offset)) {
Chris Mason39be25c2008-11-10 11:50:50 -05002151 page->mapping->a_ops->invalidatepage(page, 0);
Chris Masond1310b22008-01-24 16:13:08 -05002152 unlock_page(page);
2153 return 0;
2154 }
2155
2156 if (page->index == end_index) {
2157 char *userpage;
2158
Chris Masond1310b22008-01-24 16:13:08 -05002159 userpage = kmap_atomic(page, KM_USER0);
Chris Mason7f3c74f2008-07-18 12:01:11 -04002160 memset(userpage + pg_offset, 0,
2161 PAGE_CACHE_SIZE - pg_offset);
Chris Masond1310b22008-01-24 16:13:08 -05002162 kunmap_atomic(userpage, KM_USER0);
Chris Mason211c17f2008-05-15 09:13:45 -04002163 flush_dcache_page(page);
Chris Masond1310b22008-01-24 16:13:08 -05002164 }
Chris Mason7f3c74f2008-07-18 12:01:11 -04002165 pg_offset = 0;
Chris Masond1310b22008-01-24 16:13:08 -05002166
2167 set_page_extent_mapped(page);
2168
2169 delalloc_start = start;
2170 delalloc_end = 0;
Chris Masonc8b97812008-10-29 14:49:59 -04002171 page_started = 0;
Chris Mason771ed682008-11-06 22:02:51 -05002172 if (!epd->extent_locked) {
Chris Masonf85d7d6c2009-09-18 16:03:16 -04002173 u64 delalloc_to_write = 0;
Chris Mason11c83492009-04-20 15:50:09 -04002174 /*
2175 * make sure the wbc mapping index is at least updated
2176 * to this page.
2177 */
2178 update_nr_written(page, wbc, 0);
2179
Chris Masond3977122009-01-05 21:25:51 -05002180 while (delalloc_end < page_end) {
Chris Mason771ed682008-11-06 22:02:51 -05002181 nr_delalloc = find_lock_delalloc_range(inode, tree,
Chris Masonc8b97812008-10-29 14:49:59 -04002182 page,
2183 &delalloc_start,
Chris Masond1310b22008-01-24 16:13:08 -05002184 &delalloc_end,
2185 128 * 1024 * 1024);
Chris Mason771ed682008-11-06 22:02:51 -05002186 if (nr_delalloc == 0) {
2187 delalloc_start = delalloc_end + 1;
2188 continue;
2189 }
2190 tree->ops->fill_delalloc(inode, page, delalloc_start,
2191 delalloc_end, &page_started,
2192 &nr_written);
Chris Masonf85d7d6c2009-09-18 16:03:16 -04002193 /*
2194 * delalloc_end is already one less than the total
2195 * length, so we don't subtract one from
2196 * PAGE_CACHE_SIZE
2197 */
2198 delalloc_to_write += (delalloc_end - delalloc_start +
2199 PAGE_CACHE_SIZE) >>
2200 PAGE_CACHE_SHIFT;
Chris Masond1310b22008-01-24 16:13:08 -05002201 delalloc_start = delalloc_end + 1;
Chris Masond1310b22008-01-24 16:13:08 -05002202 }
Chris Masonf85d7d6c2009-09-18 16:03:16 -04002203 if (wbc->nr_to_write < delalloc_to_write) {
2204 int thresh = 8192;
2205
2206 if (delalloc_to_write < thresh * 2)
2207 thresh = delalloc_to_write;
2208 wbc->nr_to_write = min_t(u64, delalloc_to_write,
2209 thresh);
2210 }
Chris Masonc8b97812008-10-29 14:49:59 -04002211
Chris Mason771ed682008-11-06 22:02:51 -05002212 /* did the fill delalloc function already unlock and start
2213 * the IO?
2214 */
2215 if (page_started) {
2216 ret = 0;
Chris Mason11c83492009-04-20 15:50:09 -04002217 /*
2218 * we've unlocked the page, so we can't update
2219 * the mapping's writeback index, just update
2220 * nr_to_write.
2221 */
2222 wbc->nr_to_write -= nr_written;
2223 goto done_unlocked;
Chris Mason771ed682008-11-06 22:02:51 -05002224 }
Chris Masonc8b97812008-10-29 14:49:59 -04002225 }
Chris Mason247e7432008-07-17 12:53:51 -04002226 if (tree->ops && tree->ops->writepage_start_hook) {
Chris Masonc8b97812008-10-29 14:49:59 -04002227 ret = tree->ops->writepage_start_hook(page, start,
2228 page_end);
Chris Mason247e7432008-07-17 12:53:51 -04002229 if (ret == -EAGAIN) {
Chris Mason247e7432008-07-17 12:53:51 -04002230 redirty_page_for_writepage(wbc, page);
Chris Mason11c83492009-04-20 15:50:09 -04002231 update_nr_written(page, wbc, nr_written);
Chris Mason247e7432008-07-17 12:53:51 -04002232 unlock_page(page);
Chris Mason771ed682008-11-06 22:02:51 -05002233 ret = 0;
Chris Mason11c83492009-04-20 15:50:09 -04002234 goto done_unlocked;
Chris Mason247e7432008-07-17 12:53:51 -04002235 }
2236 }
2237
Chris Mason11c83492009-04-20 15:50:09 -04002238 /*
2239 * we don't want to touch the inode after unlocking the page,
2240 * so we update the mapping writeback index now
2241 */
2242 update_nr_written(page, wbc, nr_written + 1);
Chris Mason771ed682008-11-06 22:02:51 -05002243
Chris Masond1310b22008-01-24 16:13:08 -05002244 end = page_end;
Chris Masond1310b22008-01-24 16:13:08 -05002245 if (last_byte <= start) {
Chris Masone6dcd2d2008-07-17 12:53:50 -04002246 if (tree->ops && tree->ops->writepage_end_io_hook)
2247 tree->ops->writepage_end_io_hook(page, start,
2248 page_end, NULL, 1);
Chris Masond1310b22008-01-24 16:13:08 -05002249 goto done;
2250 }
2251
Chris Masond1310b22008-01-24 16:13:08 -05002252 blocksize = inode->i_sb->s_blocksize;
2253
2254 while (cur <= end) {
2255 if (cur >= last_byte) {
Chris Masone6dcd2d2008-07-17 12:53:50 -04002256 if (tree->ops && tree->ops->writepage_end_io_hook)
2257 tree->ops->writepage_end_io_hook(page, cur,
2258 page_end, NULL, 1);
Chris Masond1310b22008-01-24 16:13:08 -05002259 break;
2260 }
Chris Mason7f3c74f2008-07-18 12:01:11 -04002261 em = epd->get_extent(inode, page, pg_offset, cur,
Chris Masond1310b22008-01-24 16:13:08 -05002262 end - cur + 1, 1);
David Sterbac7040052011-04-19 18:00:01 +02002263 if (IS_ERR_OR_NULL(em)) {
Chris Masond1310b22008-01-24 16:13:08 -05002264 SetPageError(page);
2265 break;
2266 }
2267
2268 extent_offset = cur - em->start;
2269 BUG_ON(extent_map_end(em) <= cur);
2270 BUG_ON(end < cur);
2271 iosize = min(extent_map_end(em) - cur, end - cur + 1);
2272 iosize = (iosize + blocksize - 1) & ~((u64)blocksize - 1);
2273 sector = (em->block_start + extent_offset) >> 9;
2274 bdev = em->bdev;
2275 block_start = em->block_start;
Chris Masonc8b97812008-10-29 14:49:59 -04002276 compressed = test_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
Chris Masond1310b22008-01-24 16:13:08 -05002277 free_extent_map(em);
2278 em = NULL;
2279
Chris Masonc8b97812008-10-29 14:49:59 -04002280 /*
2281 * compressed and inline extents are written through other
2282 * paths in the FS
2283 */
2284 if (compressed || block_start == EXTENT_MAP_HOLE ||
Chris Masond1310b22008-01-24 16:13:08 -05002285 block_start == EXTENT_MAP_INLINE) {
Chris Masonc8b97812008-10-29 14:49:59 -04002286 /*
2287 * end_io notification does not happen here for
2288 * compressed extents
2289 */
2290 if (!compressed && tree->ops &&
2291 tree->ops->writepage_end_io_hook)
Chris Masone6dcd2d2008-07-17 12:53:50 -04002292 tree->ops->writepage_end_io_hook(page, cur,
2293 cur + iosize - 1,
2294 NULL, 1);
Chris Masonc8b97812008-10-29 14:49:59 -04002295 else if (compressed) {
2296 /* we don't want to end_page_writeback on
2297 * a compressed extent. this happens
2298 * elsewhere
2299 */
2300 nr++;
2301 }
2302
2303 cur += iosize;
Chris Mason7f3c74f2008-07-18 12:01:11 -04002304 pg_offset += iosize;
Chris Masond1310b22008-01-24 16:13:08 -05002305 continue;
2306 }
Chris Masond1310b22008-01-24 16:13:08 -05002307 /* leave this out until we have a page_mkwrite call */
2308 if (0 && !test_range_bit(tree, cur, cur + iosize - 1,
Chris Mason9655d292009-09-02 15:22:30 -04002309 EXTENT_DIRTY, 0, NULL)) {
Chris Masond1310b22008-01-24 16:13:08 -05002310 cur = cur + iosize;
Chris Mason7f3c74f2008-07-18 12:01:11 -04002311 pg_offset += iosize;
Chris Masond1310b22008-01-24 16:13:08 -05002312 continue;
2313 }
Chris Masonc8b97812008-10-29 14:49:59 -04002314
Chris Masond1310b22008-01-24 16:13:08 -05002315 if (tree->ops && tree->ops->writepage_io_hook) {
2316 ret = tree->ops->writepage_io_hook(page, cur,
2317 cur + iosize - 1);
2318 } else {
2319 ret = 0;
2320 }
Chris Mason1259ab72008-05-12 13:39:03 -04002321 if (ret) {
Chris Masond1310b22008-01-24 16:13:08 -05002322 SetPageError(page);
Chris Mason1259ab72008-05-12 13:39:03 -04002323 } else {
Chris Masond1310b22008-01-24 16:13:08 -05002324 unsigned long max_nr = end_index + 1;
Chris Mason7f3c74f2008-07-18 12:01:11 -04002325
Chris Masond1310b22008-01-24 16:13:08 -05002326 set_range_writeback(tree, cur, cur + iosize - 1);
2327 if (!PageWriteback(page)) {
Chris Masond3977122009-01-05 21:25:51 -05002328 printk(KERN_ERR "btrfs warning page %lu not "
2329 "writeback, cur %llu end %llu\n",
2330 page->index, (unsigned long long)cur,
Chris Masond1310b22008-01-24 16:13:08 -05002331 (unsigned long long)end);
2332 }
2333
Chris Masonffbd5172009-04-20 15:50:09 -04002334 ret = submit_extent_page(write_flags, tree, page,
2335 sector, iosize, pg_offset,
2336 bdev, &epd->bio, max_nr,
Chris Masonc8b97812008-10-29 14:49:59 -04002337 end_bio_extent_writepage,
2338 0, 0, 0);
Chris Masond1310b22008-01-24 16:13:08 -05002339 if (ret)
2340 SetPageError(page);
2341 }
2342 cur = cur + iosize;
Chris Mason7f3c74f2008-07-18 12:01:11 -04002343 pg_offset += iosize;
Chris Masond1310b22008-01-24 16:13:08 -05002344 nr++;
2345 }
2346done:
2347 if (nr == 0) {
2348 /* make sure the mapping tag for page dirty gets cleared */
2349 set_page_writeback(page);
2350 end_page_writeback(page);
2351 }
Chris Masond1310b22008-01-24 16:13:08 -05002352 unlock_page(page);
Chris Mason771ed682008-11-06 22:02:51 -05002353
Chris Mason11c83492009-04-20 15:50:09 -04002354done_unlocked:
2355
Chris Mason2c64c532009-09-02 15:04:12 -04002356 /* drop our reference on any cached states */
2357 free_extent_state(cached_state);
Chris Masond1310b22008-01-24 16:13:08 -05002358 return 0;
2359}
2360
Chris Masond1310b22008-01-24 16:13:08 -05002361/**
Chris Mason4bef0842008-09-08 11:18:08 -04002362 * write_cache_pages - walk the list of dirty pages of the given address space and write all of them.
Chris Masond1310b22008-01-24 16:13:08 -05002363 * @mapping: address space structure to write
2364 * @wbc: subtract the number of written pages from *@wbc->nr_to_write
2365 * @writepage: function called for each page
2366 * @data: data passed to writepage function
2367 *
2368 * If a page is already under I/O, write_cache_pages() skips it, even
2369 * if it's dirty. This is desirable behaviour for memory-cleaning writeback,
2370 * but it is INCORRECT for data-integrity system calls such as fsync(). fsync()
2371 * and msync() need to guarantee that all the data which was dirty at the time
2372 * the call was made get new I/O started against them. If wbc->sync_mode is
2373 * WB_SYNC_ALL then we were called for data integrity and we must wait for
2374 * existing IO to complete.
2375 */
Christoph Hellwigb2950862008-12-02 09:54:17 -05002376static int extent_write_cache_pages(struct extent_io_tree *tree,
Chris Mason4bef0842008-09-08 11:18:08 -04002377 struct address_space *mapping,
2378 struct writeback_control *wbc,
Chris Masond2c3f4f2008-11-19 12:44:22 -05002379 writepage_t writepage, void *data,
2380 void (*flush_fn)(void *))
Chris Masond1310b22008-01-24 16:13:08 -05002381{
Chris Masond1310b22008-01-24 16:13:08 -05002382 int ret = 0;
2383 int done = 0;
Chris Masonf85d7d6c2009-09-18 16:03:16 -04002384 int nr_to_write_done = 0;
Chris Masond1310b22008-01-24 16:13:08 -05002385 struct pagevec pvec;
2386 int nr_pages;
2387 pgoff_t index;
2388 pgoff_t end; /* Inclusive */
2389 int scanned = 0;
Josef Bacikf7aaa062011-07-15 21:26:38 +00002390 int tag;
Chris Masond1310b22008-01-24 16:13:08 -05002391
Chris Masond1310b22008-01-24 16:13:08 -05002392 pagevec_init(&pvec, 0);
2393 if (wbc->range_cyclic) {
2394 index = mapping->writeback_index; /* Start from prev offset */
2395 end = -1;
2396 } else {
2397 index = wbc->range_start >> PAGE_CACHE_SHIFT;
2398 end = wbc->range_end >> PAGE_CACHE_SHIFT;
Chris Masond1310b22008-01-24 16:13:08 -05002399 scanned = 1;
2400 }
Josef Bacikf7aaa062011-07-15 21:26:38 +00002401 if (wbc->sync_mode == WB_SYNC_ALL)
2402 tag = PAGECACHE_TAG_TOWRITE;
2403 else
2404 tag = PAGECACHE_TAG_DIRTY;
Chris Masond1310b22008-01-24 16:13:08 -05002405retry:
Josef Bacikf7aaa062011-07-15 21:26:38 +00002406 if (wbc->sync_mode == WB_SYNC_ALL)
2407 tag_pages_for_writeback(mapping, index, end);
Chris Masonf85d7d6c2009-09-18 16:03:16 -04002408 while (!done && !nr_to_write_done && (index <= end) &&
Josef Bacikf7aaa062011-07-15 21:26:38 +00002409 (nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, tag,
2410 min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1))) {
Chris Masond1310b22008-01-24 16:13:08 -05002411 unsigned i;
2412
2413 scanned = 1;
2414 for (i = 0; i < nr_pages; i++) {
2415 struct page *page = pvec.pages[i];
2416
2417 /*
2418 * At this point we hold neither mapping->tree_lock nor
2419 * lock on the page itself: the page may be truncated or
2420 * invalidated (changing page->mapping to NULL), or even
2421 * swizzled back from swapper_space to tmpfs file
2422 * mapping
2423 */
Chris Mason4bef0842008-09-08 11:18:08 -04002424 if (tree->ops && tree->ops->write_cache_pages_lock_hook)
2425 tree->ops->write_cache_pages_lock_hook(page);
2426 else
2427 lock_page(page);
Chris Masond1310b22008-01-24 16:13:08 -05002428
2429 if (unlikely(page->mapping != mapping)) {
2430 unlock_page(page);
2431 continue;
2432 }
2433
2434 if (!wbc->range_cyclic && page->index > end) {
2435 done = 1;
2436 unlock_page(page);
2437 continue;
2438 }
2439
Chris Masond2c3f4f2008-11-19 12:44:22 -05002440 if (wbc->sync_mode != WB_SYNC_NONE) {
Chris Mason0e6bd952008-11-20 10:46:35 -05002441 if (PageWriteback(page))
2442 flush_fn(data);
Chris Masond1310b22008-01-24 16:13:08 -05002443 wait_on_page_writeback(page);
Chris Masond2c3f4f2008-11-19 12:44:22 -05002444 }
Chris Masond1310b22008-01-24 16:13:08 -05002445
2446 if (PageWriteback(page) ||
2447 !clear_page_dirty_for_io(page)) {
2448 unlock_page(page);
2449 continue;
2450 }
2451
2452 ret = (*writepage)(page, wbc, data);
2453
2454 if (unlikely(ret == AOP_WRITEPAGE_ACTIVATE)) {
2455 unlock_page(page);
2456 ret = 0;
2457 }
Chris Masonf85d7d6c2009-09-18 16:03:16 -04002458 if (ret)
Chris Masond1310b22008-01-24 16:13:08 -05002459 done = 1;
Chris Masonf85d7d6c2009-09-18 16:03:16 -04002460
2461 /*
2462 * the filesystem may choose to bump up nr_to_write.
2463 * We have to make sure to honor the new nr_to_write
2464 * at any time
2465 */
2466 nr_to_write_done = wbc->nr_to_write <= 0;
Chris Masond1310b22008-01-24 16:13:08 -05002467 }
2468 pagevec_release(&pvec);
2469 cond_resched();
2470 }
2471 if (!scanned && !done) {
2472 /*
2473 * We hit the last page and there is more work to be done: wrap
2474 * back to the start of the file
2475 */
2476 scanned = 1;
2477 index = 0;
2478 goto retry;
2479 }
Chris Masond1310b22008-01-24 16:13:08 -05002480 return ret;
2481}
Chris Masond1310b22008-01-24 16:13:08 -05002482
Chris Masonffbd5172009-04-20 15:50:09 -04002483static void flush_epd_write_bio(struct extent_page_data *epd)
2484{
2485 if (epd->bio) {
2486 if (epd->sync_io)
2487 submit_one_bio(WRITE_SYNC, epd->bio, 0, 0);
2488 else
2489 submit_one_bio(WRITE, epd->bio, 0, 0);
2490 epd->bio = NULL;
2491 }
2492}
2493
Chris Masond2c3f4f2008-11-19 12:44:22 -05002494static noinline void flush_write_bio(void *data)
2495{
2496 struct extent_page_data *epd = data;
Chris Masonffbd5172009-04-20 15:50:09 -04002497 flush_epd_write_bio(epd);
Chris Masond2c3f4f2008-11-19 12:44:22 -05002498}
2499
Chris Masond1310b22008-01-24 16:13:08 -05002500int extent_write_full_page(struct extent_io_tree *tree, struct page *page,
2501 get_extent_t *get_extent,
2502 struct writeback_control *wbc)
2503{
2504 int ret;
Chris Masond1310b22008-01-24 16:13:08 -05002505 struct extent_page_data epd = {
2506 .bio = NULL,
2507 .tree = tree,
2508 .get_extent = get_extent,
Chris Mason771ed682008-11-06 22:02:51 -05002509 .extent_locked = 0,
Chris Masonffbd5172009-04-20 15:50:09 -04002510 .sync_io = wbc->sync_mode == WB_SYNC_ALL,
Chris Masond1310b22008-01-24 16:13:08 -05002511 };
Chris Masond1310b22008-01-24 16:13:08 -05002512
Chris Masond1310b22008-01-24 16:13:08 -05002513 ret = __extent_writepage(page, wbc, &epd);
2514
Chris Masonffbd5172009-04-20 15:50:09 -04002515 flush_epd_write_bio(&epd);
Chris Masond1310b22008-01-24 16:13:08 -05002516 return ret;
2517}
Chris Masond1310b22008-01-24 16:13:08 -05002518
Chris Mason771ed682008-11-06 22:02:51 -05002519int extent_write_locked_range(struct extent_io_tree *tree, struct inode *inode,
2520 u64 start, u64 end, get_extent_t *get_extent,
2521 int mode)
2522{
2523 int ret = 0;
2524 struct address_space *mapping = inode->i_mapping;
2525 struct page *page;
2526 unsigned long nr_pages = (end - start + PAGE_CACHE_SIZE) >>
2527 PAGE_CACHE_SHIFT;
2528
2529 struct extent_page_data epd = {
2530 .bio = NULL,
2531 .tree = tree,
2532 .get_extent = get_extent,
2533 .extent_locked = 1,
Chris Masonffbd5172009-04-20 15:50:09 -04002534 .sync_io = mode == WB_SYNC_ALL,
Chris Mason771ed682008-11-06 22:02:51 -05002535 };
2536 struct writeback_control wbc_writepages = {
Chris Mason771ed682008-11-06 22:02:51 -05002537 .sync_mode = mode,
Chris Mason771ed682008-11-06 22:02:51 -05002538 .nr_to_write = nr_pages * 2,
2539 .range_start = start,
2540 .range_end = end + 1,
2541 };
2542
Chris Masond3977122009-01-05 21:25:51 -05002543 while (start <= end) {
Chris Mason771ed682008-11-06 22:02:51 -05002544 page = find_get_page(mapping, start >> PAGE_CACHE_SHIFT);
2545 if (clear_page_dirty_for_io(page))
2546 ret = __extent_writepage(page, &wbc_writepages, &epd);
2547 else {
2548 if (tree->ops && tree->ops->writepage_end_io_hook)
2549 tree->ops->writepage_end_io_hook(page, start,
2550 start + PAGE_CACHE_SIZE - 1,
2551 NULL, 1);
2552 unlock_page(page);
2553 }
2554 page_cache_release(page);
2555 start += PAGE_CACHE_SIZE;
2556 }
2557
Chris Masonffbd5172009-04-20 15:50:09 -04002558 flush_epd_write_bio(&epd);
Chris Mason771ed682008-11-06 22:02:51 -05002559 return ret;
2560}
Chris Masond1310b22008-01-24 16:13:08 -05002561
2562int extent_writepages(struct extent_io_tree *tree,
2563 struct address_space *mapping,
2564 get_extent_t *get_extent,
2565 struct writeback_control *wbc)
2566{
2567 int ret = 0;
2568 struct extent_page_data epd = {
2569 .bio = NULL,
2570 .tree = tree,
2571 .get_extent = get_extent,
Chris Mason771ed682008-11-06 22:02:51 -05002572 .extent_locked = 0,
Chris Masonffbd5172009-04-20 15:50:09 -04002573 .sync_io = wbc->sync_mode == WB_SYNC_ALL,
Chris Masond1310b22008-01-24 16:13:08 -05002574 };
2575
Chris Mason4bef0842008-09-08 11:18:08 -04002576 ret = extent_write_cache_pages(tree, mapping, wbc,
Chris Masond2c3f4f2008-11-19 12:44:22 -05002577 __extent_writepage, &epd,
2578 flush_write_bio);
Chris Masonffbd5172009-04-20 15:50:09 -04002579 flush_epd_write_bio(&epd);
Chris Masond1310b22008-01-24 16:13:08 -05002580 return ret;
2581}
Chris Masond1310b22008-01-24 16:13:08 -05002582
2583int extent_readpages(struct extent_io_tree *tree,
2584 struct address_space *mapping,
2585 struct list_head *pages, unsigned nr_pages,
2586 get_extent_t get_extent)
2587{
2588 struct bio *bio = NULL;
2589 unsigned page_idx;
Chris Masonc8b97812008-10-29 14:49:59 -04002590 unsigned long bio_flags = 0;
Chris Masond1310b22008-01-24 16:13:08 -05002591
Chris Masond1310b22008-01-24 16:13:08 -05002592 for (page_idx = 0; page_idx < nr_pages; page_idx++) {
2593 struct page *page = list_entry(pages->prev, struct page, lru);
2594
2595 prefetchw(&page->flags);
2596 list_del(&page->lru);
Nick Piggin28ecb6092010-03-17 13:31:04 +00002597 if (!add_to_page_cache_lru(page, mapping,
Itaru Kitayama43e817a2011-04-25 19:43:51 -04002598 page->index, GFP_NOFS)) {
Chris Masonf1885912008-04-09 16:28:12 -04002599 __extent_read_full_page(tree, page, get_extent,
Chris Masonc8b97812008-10-29 14:49:59 -04002600 &bio, 0, &bio_flags);
Chris Masond1310b22008-01-24 16:13:08 -05002601 }
2602 page_cache_release(page);
2603 }
Chris Masond1310b22008-01-24 16:13:08 -05002604 BUG_ON(!list_empty(pages));
2605 if (bio)
Chris Masonc8b97812008-10-29 14:49:59 -04002606 submit_one_bio(READ, bio, 0, bio_flags);
Chris Masond1310b22008-01-24 16:13:08 -05002607 return 0;
2608}
Chris Masond1310b22008-01-24 16:13:08 -05002609
2610/*
2611 * basic invalidatepage code, this waits on any locked or writeback
2612 * ranges corresponding to the page, and then deletes any extent state
2613 * records from the tree
2614 */
2615int extent_invalidatepage(struct extent_io_tree *tree,
2616 struct page *page, unsigned long offset)
2617{
Josef Bacik2ac55d42010-02-03 19:33:23 +00002618 struct extent_state *cached_state = NULL;
Chris Masond1310b22008-01-24 16:13:08 -05002619 u64 start = ((u64)page->index << PAGE_CACHE_SHIFT);
2620 u64 end = start + PAGE_CACHE_SIZE - 1;
2621 size_t blocksize = page->mapping->host->i_sb->s_blocksize;
2622
Chris Masond3977122009-01-05 21:25:51 -05002623 start += (offset + blocksize - 1) & ~(blocksize - 1);
Chris Masond1310b22008-01-24 16:13:08 -05002624 if (start > end)
2625 return 0;
2626
Josef Bacik2ac55d42010-02-03 19:33:23 +00002627 lock_extent_bits(tree, start, end, 0, &cached_state, GFP_NOFS);
Chris Mason1edbb732009-09-02 13:24:36 -04002628 wait_on_page_writeback(page);
Chris Masond1310b22008-01-24 16:13:08 -05002629 clear_extent_bit(tree, start, end,
Josef Bacik32c00af2009-10-08 13:34:05 -04002630 EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC |
2631 EXTENT_DO_ACCOUNTING,
Josef Bacik2ac55d42010-02-03 19:33:23 +00002632 1, 1, &cached_state, GFP_NOFS);
Chris Masond1310b22008-01-24 16:13:08 -05002633 return 0;
2634}
Chris Masond1310b22008-01-24 16:13:08 -05002635
2636/*
Chris Mason7b13b7b2008-04-18 10:29:50 -04002637 * a helper for releasepage, this tests for areas of the page that
2638 * are locked or under IO and drops the related state bits if it is safe
2639 * to drop the page.
2640 */
2641int try_release_extent_state(struct extent_map_tree *map,
2642 struct extent_io_tree *tree, struct page *page,
2643 gfp_t mask)
2644{
2645 u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
2646 u64 end = start + PAGE_CACHE_SIZE - 1;
2647 int ret = 1;
2648
Chris Mason211f90e2008-07-18 11:56:15 -04002649 if (test_range_bit(tree, start, end,
Chris Mason8b62b722009-09-02 16:53:46 -04002650 EXTENT_IOBITS, 0, NULL))
Chris Mason7b13b7b2008-04-18 10:29:50 -04002651 ret = 0;
2652 else {
2653 if ((mask & GFP_NOFS) == GFP_NOFS)
2654 mask = GFP_NOFS;
Chris Mason11ef1602009-09-23 20:28:46 -04002655 /*
2656 * at this point we can safely clear everything except the
2657 * locked bit and the nodatasum bit
2658 */
Chris Masone3f24cc2011-02-14 12:52:08 -05002659 ret = clear_extent_bit(tree, start, end,
Chris Mason11ef1602009-09-23 20:28:46 -04002660 ~(EXTENT_LOCKED | EXTENT_NODATASUM),
2661 0, 0, NULL, mask);
Chris Masone3f24cc2011-02-14 12:52:08 -05002662
2663 /* if clear_extent_bit failed for enomem reasons,
2664 * we can't allow the release to continue.
2665 */
2666 if (ret < 0)
2667 ret = 0;
2668 else
2669 ret = 1;
Chris Mason7b13b7b2008-04-18 10:29:50 -04002670 }
2671 return ret;
2672}
Chris Mason7b13b7b2008-04-18 10:29:50 -04002673
2674/*
Chris Masond1310b22008-01-24 16:13:08 -05002675 * a helper for releasepage. As long as there are no locked extents
2676 * in the range corresponding to the page, both state records and extent
2677 * map records are removed
2678 */
2679int try_release_extent_mapping(struct extent_map_tree *map,
Chris Mason70dec802008-01-29 09:59:12 -05002680 struct extent_io_tree *tree, struct page *page,
2681 gfp_t mask)
Chris Masond1310b22008-01-24 16:13:08 -05002682{
2683 struct extent_map *em;
2684 u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
2685 u64 end = start + PAGE_CACHE_SIZE - 1;
Chris Mason7b13b7b2008-04-18 10:29:50 -04002686
Chris Mason70dec802008-01-29 09:59:12 -05002687 if ((mask & __GFP_WAIT) &&
2688 page->mapping->host->i_size > 16 * 1024 * 1024) {
Yan39b56372008-02-15 10:40:50 -05002689 u64 len;
Chris Mason70dec802008-01-29 09:59:12 -05002690 while (start <= end) {
Yan39b56372008-02-15 10:40:50 -05002691 len = end - start + 1;
Chris Mason890871b2009-09-02 16:24:52 -04002692 write_lock(&map->lock);
Yan39b56372008-02-15 10:40:50 -05002693 em = lookup_extent_mapping(map, start, len);
David Sterbac7040052011-04-19 18:00:01 +02002694 if (IS_ERR_OR_NULL(em)) {
Chris Mason890871b2009-09-02 16:24:52 -04002695 write_unlock(&map->lock);
Chris Mason70dec802008-01-29 09:59:12 -05002696 break;
2697 }
Chris Mason7f3c74f2008-07-18 12:01:11 -04002698 if (test_bit(EXTENT_FLAG_PINNED, &em->flags) ||
2699 em->start != start) {
Chris Mason890871b2009-09-02 16:24:52 -04002700 write_unlock(&map->lock);
Chris Mason70dec802008-01-29 09:59:12 -05002701 free_extent_map(em);
2702 break;
2703 }
2704 if (!test_range_bit(tree, em->start,
2705 extent_map_end(em) - 1,
Chris Mason8b62b722009-09-02 16:53:46 -04002706 EXTENT_LOCKED | EXTENT_WRITEBACK,
Chris Mason9655d292009-09-02 15:22:30 -04002707 0, NULL)) {
Chris Mason70dec802008-01-29 09:59:12 -05002708 remove_extent_mapping(map, em);
2709 /* once for the rb tree */
2710 free_extent_map(em);
2711 }
2712 start = extent_map_end(em);
Chris Mason890871b2009-09-02 16:24:52 -04002713 write_unlock(&map->lock);
Chris Mason70dec802008-01-29 09:59:12 -05002714
2715 /* once for us */
Chris Masond1310b22008-01-24 16:13:08 -05002716 free_extent_map(em);
2717 }
Chris Masond1310b22008-01-24 16:13:08 -05002718 }
Chris Mason7b13b7b2008-04-18 10:29:50 -04002719 return try_release_extent_state(map, tree, page, mask);
Chris Masond1310b22008-01-24 16:13:08 -05002720}
Chris Masond1310b22008-01-24 16:13:08 -05002721
Chris Masonec29ed52011-02-23 16:23:20 -05002722/*
2723 * helper function for fiemap, which doesn't want to see any holes.
2724 * This maps until we find something past 'last'
2725 */
2726static struct extent_map *get_extent_skip_holes(struct inode *inode,
2727 u64 offset,
2728 u64 last,
2729 get_extent_t *get_extent)
2730{
2731 u64 sectorsize = BTRFS_I(inode)->root->sectorsize;
2732 struct extent_map *em;
2733 u64 len;
2734
2735 if (offset >= last)
2736 return NULL;
2737
2738 while(1) {
2739 len = last - offset;
2740 if (len == 0)
2741 break;
2742 len = (len + sectorsize - 1) & ~(sectorsize - 1);
2743 em = get_extent(inode, NULL, 0, offset, len, 0);
David Sterbac7040052011-04-19 18:00:01 +02002744 if (IS_ERR_OR_NULL(em))
Chris Masonec29ed52011-02-23 16:23:20 -05002745 return em;
2746
2747 /* if this isn't a hole return it */
2748 if (!test_bit(EXTENT_FLAG_VACANCY, &em->flags) &&
2749 em->block_start != EXTENT_MAP_HOLE) {
2750 return em;
2751 }
2752
2753 /* this is a hole, advance to the next extent */
2754 offset = extent_map_end(em);
2755 free_extent_map(em);
2756 if (offset >= last)
2757 break;
2758 }
2759 return NULL;
2760}
2761
Yehuda Sadeh1506fcc2009-01-21 14:39:14 -05002762int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
2763 __u64 start, __u64 len, get_extent_t *get_extent)
2764{
Josef Bacik975f84f2010-11-23 19:36:57 +00002765 int ret = 0;
Yehuda Sadeh1506fcc2009-01-21 14:39:14 -05002766 u64 off = start;
2767 u64 max = start + len;
2768 u32 flags = 0;
Josef Bacik975f84f2010-11-23 19:36:57 +00002769 u32 found_type;
2770 u64 last;
Chris Masonec29ed52011-02-23 16:23:20 -05002771 u64 last_for_get_extent = 0;
Yehuda Sadeh1506fcc2009-01-21 14:39:14 -05002772 u64 disko = 0;
Chris Masonec29ed52011-02-23 16:23:20 -05002773 u64 isize = i_size_read(inode);
Josef Bacik975f84f2010-11-23 19:36:57 +00002774 struct btrfs_key found_key;
Yehuda Sadeh1506fcc2009-01-21 14:39:14 -05002775 struct extent_map *em = NULL;
Josef Bacik2ac55d42010-02-03 19:33:23 +00002776 struct extent_state *cached_state = NULL;
Josef Bacik975f84f2010-11-23 19:36:57 +00002777 struct btrfs_path *path;
2778 struct btrfs_file_extent_item *item;
Yehuda Sadeh1506fcc2009-01-21 14:39:14 -05002779 int end = 0;
Chris Masonec29ed52011-02-23 16:23:20 -05002780 u64 em_start = 0;
2781 u64 em_len = 0;
2782 u64 em_end = 0;
Yehuda Sadeh1506fcc2009-01-21 14:39:14 -05002783 unsigned long emflags;
Yehuda Sadeh1506fcc2009-01-21 14:39:14 -05002784
2785 if (len == 0)
2786 return -EINVAL;
2787
Josef Bacik975f84f2010-11-23 19:36:57 +00002788 path = btrfs_alloc_path();
2789 if (!path)
2790 return -ENOMEM;
2791 path->leave_spinning = 1;
2792
Chris Masonec29ed52011-02-23 16:23:20 -05002793 /*
2794 * lookup the last file extent. We're not using i_size here
2795 * because there might be preallocation past i_size
2796 */
Josef Bacik975f84f2010-11-23 19:36:57 +00002797 ret = btrfs_lookup_file_extent(NULL, BTRFS_I(inode)->root,
Li Zefan33345d012011-04-20 10:31:50 +08002798 path, btrfs_ino(inode), -1, 0);
Josef Bacik975f84f2010-11-23 19:36:57 +00002799 if (ret < 0) {
2800 btrfs_free_path(path);
2801 return ret;
2802 }
2803 WARN_ON(!ret);
2804 path->slots[0]--;
2805 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
2806 struct btrfs_file_extent_item);
2807 btrfs_item_key_to_cpu(path->nodes[0], &found_key, path->slots[0]);
2808 found_type = btrfs_key_type(&found_key);
2809
Chris Masonec29ed52011-02-23 16:23:20 -05002810 /* No extents, but there might be delalloc bits */
Li Zefan33345d012011-04-20 10:31:50 +08002811 if (found_key.objectid != btrfs_ino(inode) ||
Josef Bacik975f84f2010-11-23 19:36:57 +00002812 found_type != BTRFS_EXTENT_DATA_KEY) {
Chris Masonec29ed52011-02-23 16:23:20 -05002813 /* have to trust i_size as the end */
2814 last = (u64)-1;
2815 last_for_get_extent = isize;
2816 } else {
2817 /*
2818 * remember the start of the last extent. There are a
2819 * bunch of different factors that go into the length of the
2820 * extent, so its much less complex to remember where it started
2821 */
2822 last = found_key.offset;
2823 last_for_get_extent = last + 1;
Josef Bacik975f84f2010-11-23 19:36:57 +00002824 }
Josef Bacik975f84f2010-11-23 19:36:57 +00002825 btrfs_free_path(path);
2826
Chris Masonec29ed52011-02-23 16:23:20 -05002827 /*
2828 * we might have some extents allocated but more delalloc past those
2829 * extents. so, we trust isize unless the start of the last extent is
2830 * beyond isize
2831 */
2832 if (last < isize) {
2833 last = (u64)-1;
2834 last_for_get_extent = isize;
2835 }
2836
Josef Bacik2ac55d42010-02-03 19:33:23 +00002837 lock_extent_bits(&BTRFS_I(inode)->io_tree, start, start + len, 0,
2838 &cached_state, GFP_NOFS);
Chris Masonec29ed52011-02-23 16:23:20 -05002839
2840 em = get_extent_skip_holes(inode, off, last_for_get_extent,
2841 get_extent);
Yehuda Sadeh1506fcc2009-01-21 14:39:14 -05002842 if (!em)
2843 goto out;
2844 if (IS_ERR(em)) {
2845 ret = PTR_ERR(em);
2846 goto out;
2847 }
Josef Bacik975f84f2010-11-23 19:36:57 +00002848
Yehuda Sadeh1506fcc2009-01-21 14:39:14 -05002849 while (!end) {
Chris Masonea8efc72011-03-08 11:54:40 -05002850 u64 offset_in_extent;
Yehuda Sadeh1506fcc2009-01-21 14:39:14 -05002851
Chris Masonea8efc72011-03-08 11:54:40 -05002852 /* break if the extent we found is outside the range */
2853 if (em->start >= max || extent_map_end(em) < off)
2854 break;
2855
2856 /*
2857 * get_extent may return an extent that starts before our
2858 * requested range. We have to make sure the ranges
2859 * we return to fiemap always move forward and don't
2860 * overlap, so adjust the offsets here
2861 */
2862 em_start = max(em->start, off);
2863
2864 /*
2865 * record the offset from the start of the extent
2866 * for adjusting the disk offset below
2867 */
2868 offset_in_extent = em_start - em->start;
Chris Masonec29ed52011-02-23 16:23:20 -05002869 em_end = extent_map_end(em);
Chris Masonea8efc72011-03-08 11:54:40 -05002870 em_len = em_end - em_start;
Chris Masonec29ed52011-02-23 16:23:20 -05002871 emflags = em->flags;
Yehuda Sadeh1506fcc2009-01-21 14:39:14 -05002872 disko = 0;
2873 flags = 0;
2874
Chris Masonea8efc72011-03-08 11:54:40 -05002875 /*
2876 * bump off for our next call to get_extent
2877 */
2878 off = extent_map_end(em);
2879 if (off >= max)
2880 end = 1;
2881
Heiko Carstens93dbfad2009-04-03 10:33:45 -04002882 if (em->block_start == EXTENT_MAP_LAST_BYTE) {
Yehuda Sadeh1506fcc2009-01-21 14:39:14 -05002883 end = 1;
2884 flags |= FIEMAP_EXTENT_LAST;
Heiko Carstens93dbfad2009-04-03 10:33:45 -04002885 } else if (em->block_start == EXTENT_MAP_INLINE) {
Yehuda Sadeh1506fcc2009-01-21 14:39:14 -05002886 flags |= (FIEMAP_EXTENT_DATA_INLINE |
2887 FIEMAP_EXTENT_NOT_ALIGNED);
Heiko Carstens93dbfad2009-04-03 10:33:45 -04002888 } else if (em->block_start == EXTENT_MAP_DELALLOC) {
Yehuda Sadeh1506fcc2009-01-21 14:39:14 -05002889 flags |= (FIEMAP_EXTENT_DELALLOC |
2890 FIEMAP_EXTENT_UNKNOWN);
Heiko Carstens93dbfad2009-04-03 10:33:45 -04002891 } else {
Chris Masonea8efc72011-03-08 11:54:40 -05002892 disko = em->block_start + offset_in_extent;
Yehuda Sadeh1506fcc2009-01-21 14:39:14 -05002893 }
2894 if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags))
2895 flags |= FIEMAP_EXTENT_ENCODED;
2896
Yehuda Sadeh1506fcc2009-01-21 14:39:14 -05002897 free_extent_map(em);
2898 em = NULL;
Chris Masonec29ed52011-02-23 16:23:20 -05002899 if ((em_start >= last) || em_len == (u64)-1 ||
2900 (last == (u64)-1 && isize <= em_end)) {
Yehuda Sadeh1506fcc2009-01-21 14:39:14 -05002901 flags |= FIEMAP_EXTENT_LAST;
2902 end = 1;
2903 }
2904
Chris Masonec29ed52011-02-23 16:23:20 -05002905 /* now scan forward to see if this is really the last extent. */
2906 em = get_extent_skip_holes(inode, off, last_for_get_extent,
2907 get_extent);
2908 if (IS_ERR(em)) {
2909 ret = PTR_ERR(em);
2910 goto out;
2911 }
2912 if (!em) {
Josef Bacik975f84f2010-11-23 19:36:57 +00002913 flags |= FIEMAP_EXTENT_LAST;
2914 end = 1;
2915 }
Chris Masonec29ed52011-02-23 16:23:20 -05002916 ret = fiemap_fill_next_extent(fieinfo, em_start, disko,
2917 em_len, flags);
2918 if (ret)
2919 goto out_free;
Yehuda Sadeh1506fcc2009-01-21 14:39:14 -05002920 }
2921out_free:
2922 free_extent_map(em);
2923out:
Josef Bacik2ac55d42010-02-03 19:33:23 +00002924 unlock_extent_cached(&BTRFS_I(inode)->io_tree, start, start + len,
2925 &cached_state, GFP_NOFS);
Yehuda Sadeh1506fcc2009-01-21 14:39:14 -05002926 return ret;
2927}
2928
Chris Masond1310b22008-01-24 16:13:08 -05002929static inline struct page *extent_buffer_page(struct extent_buffer *eb,
2930 unsigned long i)
2931{
2932 struct page *p;
2933 struct address_space *mapping;
2934
2935 if (i == 0)
2936 return eb->first_page;
2937 i += eb->start >> PAGE_CACHE_SHIFT;
2938 mapping = eb->first_page->mapping;
Chris Mason33958dc2008-07-30 10:29:12 -04002939 if (!mapping)
2940 return NULL;
Sven Wegener0ee0fda2008-07-30 16:54:26 -04002941
2942 /*
2943 * extent_buffer_page is only called after pinning the page
2944 * by increasing the reference count. So we know the page must
2945 * be in the radix tree.
2946 */
Sven Wegener0ee0fda2008-07-30 16:54:26 -04002947 rcu_read_lock();
Chris Masond1310b22008-01-24 16:13:08 -05002948 p = radix_tree_lookup(&mapping->page_tree, i);
Sven Wegener0ee0fda2008-07-30 16:54:26 -04002949 rcu_read_unlock();
Chris Mason2b1f55b2008-09-24 11:48:04 -04002950
Chris Masond1310b22008-01-24 16:13:08 -05002951 return p;
2952}
2953
Chris Mason6af118ce2008-07-22 11:18:07 -04002954static inline unsigned long num_extent_pages(u64 start, u64 len)
Chris Masonce9adaa2008-04-09 16:28:12 -04002955{
Chris Mason6af118ce2008-07-22 11:18:07 -04002956 return ((start + len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT) -
2957 (start >> PAGE_CACHE_SHIFT);
Chris Mason728131d2008-04-09 16:28:12 -04002958}
2959
Chris Masond1310b22008-01-24 16:13:08 -05002960static struct extent_buffer *__alloc_extent_buffer(struct extent_io_tree *tree,
2961 u64 start,
2962 unsigned long len,
2963 gfp_t mask)
2964{
2965 struct extent_buffer *eb = NULL;
Chris Mason39351272009-02-04 09:24:05 -05002966#if LEAK_DEBUG
Chris Mason2d2ae542008-03-26 16:24:23 -04002967 unsigned long flags;
Chris Mason4bef0842008-09-08 11:18:08 -04002968#endif
Chris Masond1310b22008-01-24 16:13:08 -05002969
Chris Masond1310b22008-01-24 16:13:08 -05002970 eb = kmem_cache_zalloc(extent_buffer_cache, mask);
Tsutomu Itoh91ca3382011-01-05 02:32:22 +00002971 if (eb == NULL)
2972 return NULL;
Chris Masond1310b22008-01-24 16:13:08 -05002973 eb->start = start;
2974 eb->len = len;
Chris Masonbd681512011-07-16 15:23:14 -04002975 rwlock_init(&eb->lock);
2976 atomic_set(&eb->write_locks, 0);
2977 atomic_set(&eb->read_locks, 0);
2978 atomic_set(&eb->blocking_readers, 0);
2979 atomic_set(&eb->blocking_writers, 0);
2980 atomic_set(&eb->spinning_readers, 0);
2981 atomic_set(&eb->spinning_writers, 0);
2982 init_waitqueue_head(&eb->write_lock_wq);
2983 init_waitqueue_head(&eb->read_lock_wq);
Chris Masonb4ce94d2009-02-04 09:25:08 -05002984
Chris Mason39351272009-02-04 09:24:05 -05002985#if LEAK_DEBUG
Chris Mason2d2ae542008-03-26 16:24:23 -04002986 spin_lock_irqsave(&leak_lock, flags);
2987 list_add(&eb->leak_list, &buffers);
2988 spin_unlock_irqrestore(&leak_lock, flags);
Chris Mason4bef0842008-09-08 11:18:08 -04002989#endif
Chris Masond1310b22008-01-24 16:13:08 -05002990 atomic_set(&eb->refs, 1);
2991
2992 return eb;
2993}
2994
2995static void __free_extent_buffer(struct extent_buffer *eb)
2996{
Chris Mason39351272009-02-04 09:24:05 -05002997#if LEAK_DEBUG
Chris Mason2d2ae542008-03-26 16:24:23 -04002998 unsigned long flags;
2999 spin_lock_irqsave(&leak_lock, flags);
3000 list_del(&eb->leak_list);
3001 spin_unlock_irqrestore(&leak_lock, flags);
Chris Mason4bef0842008-09-08 11:18:08 -04003002#endif
Chris Masond1310b22008-01-24 16:13:08 -05003003 kmem_cache_free(extent_buffer_cache, eb);
3004}
3005
Miao Xie897ca6e2010-10-26 20:57:29 -04003006/*
3007 * Helper for releasing extent buffer page.
3008 */
3009static void btrfs_release_extent_buffer_page(struct extent_buffer *eb,
3010 unsigned long start_idx)
3011{
3012 unsigned long index;
3013 struct page *page;
3014
3015 if (!eb->first_page)
3016 return;
3017
3018 index = num_extent_pages(eb->start, eb->len);
3019 if (start_idx >= index)
3020 return;
3021
3022 do {
3023 index--;
3024 page = extent_buffer_page(eb, index);
3025 if (page)
3026 page_cache_release(page);
3027 } while (index != start_idx);
3028}
3029
3030/*
3031 * Helper for releasing the extent buffer.
3032 */
3033static inline void btrfs_release_extent_buffer(struct extent_buffer *eb)
3034{
3035 btrfs_release_extent_buffer_page(eb, 0);
3036 __free_extent_buffer(eb);
3037}
3038
Chris Masond1310b22008-01-24 16:13:08 -05003039struct extent_buffer *alloc_extent_buffer(struct extent_io_tree *tree,
3040 u64 start, unsigned long len,
David Sterbaba144192011-04-21 01:12:06 +02003041 struct page *page0)
Chris Masond1310b22008-01-24 16:13:08 -05003042{
3043 unsigned long num_pages = num_extent_pages(start, len);
3044 unsigned long i;
3045 unsigned long index = start >> PAGE_CACHE_SHIFT;
3046 struct extent_buffer *eb;
Chris Mason6af118ce2008-07-22 11:18:07 -04003047 struct extent_buffer *exists = NULL;
Chris Masond1310b22008-01-24 16:13:08 -05003048 struct page *p;
3049 struct address_space *mapping = tree->mapping;
3050 int uptodate = 1;
Miao Xie19fe0a82010-10-26 20:57:29 -04003051 int ret;
Chris Masond1310b22008-01-24 16:13:08 -05003052
Miao Xie19fe0a82010-10-26 20:57:29 -04003053 rcu_read_lock();
3054 eb = radix_tree_lookup(&tree->buffer, start >> PAGE_CACHE_SHIFT);
3055 if (eb && atomic_inc_not_zero(&eb->refs)) {
3056 rcu_read_unlock();
Josef Bacik0f9dd462008-09-23 13:14:11 -04003057 mark_page_accessed(eb->first_page);
Chris Mason6af118ce2008-07-22 11:18:07 -04003058 return eb;
3059 }
Miao Xie19fe0a82010-10-26 20:57:29 -04003060 rcu_read_unlock();
Chris Mason6af118ce2008-07-22 11:18:07 -04003061
David Sterbaba144192011-04-21 01:12:06 +02003062 eb = __alloc_extent_buffer(tree, start, len, GFP_NOFS);
Peter2b114d12008-04-01 11:21:40 -04003063 if (!eb)
Chris Masond1310b22008-01-24 16:13:08 -05003064 return NULL;
3065
Chris Masond1310b22008-01-24 16:13:08 -05003066 if (page0) {
3067 eb->first_page = page0;
3068 i = 1;
3069 index++;
3070 page_cache_get(page0);
3071 mark_page_accessed(page0);
3072 set_page_extent_mapped(page0);
Chris Masond1310b22008-01-24 16:13:08 -05003073 set_page_extent_head(page0, len);
Chris Masonf1885912008-04-09 16:28:12 -04003074 uptodate = PageUptodate(page0);
Chris Masond1310b22008-01-24 16:13:08 -05003075 } else {
3076 i = 0;
3077 }
3078 for (; i < num_pages; i++, index++) {
Chris Masona6591712011-07-19 12:04:14 -04003079 p = find_or_create_page(mapping, index, GFP_NOFS);
Chris Masond1310b22008-01-24 16:13:08 -05003080 if (!p) {
3081 WARN_ON(1);
Chris Mason6af118ce2008-07-22 11:18:07 -04003082 goto free_eb;
Chris Masond1310b22008-01-24 16:13:08 -05003083 }
3084 set_page_extent_mapped(p);
3085 mark_page_accessed(p);
3086 if (i == 0) {
3087 eb->first_page = p;
3088 set_page_extent_head(p, len);
3089 } else {
3090 set_page_private(p, EXTENT_PAGE_PRIVATE);
3091 }
3092 if (!PageUptodate(p))
3093 uptodate = 0;
Chris Masoneb14ab82011-02-10 12:35:00 -05003094
3095 /*
3096 * see below about how we avoid a nasty race with release page
3097 * and why we unlock later
3098 */
3099 if (i != 0)
3100 unlock_page(p);
Chris Masond1310b22008-01-24 16:13:08 -05003101 }
3102 if (uptodate)
Chris Masonb4ce94d2009-02-04 09:25:08 -05003103 set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
Chris Masond1310b22008-01-24 16:13:08 -05003104
Miao Xie19fe0a82010-10-26 20:57:29 -04003105 ret = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM);
3106 if (ret)
3107 goto free_eb;
3108
Chris Mason6af118ce2008-07-22 11:18:07 -04003109 spin_lock(&tree->buffer_lock);
Miao Xie19fe0a82010-10-26 20:57:29 -04003110 ret = radix_tree_insert(&tree->buffer, start >> PAGE_CACHE_SHIFT, eb);
3111 if (ret == -EEXIST) {
3112 exists = radix_tree_lookup(&tree->buffer,
3113 start >> PAGE_CACHE_SHIFT);
Chris Mason6af118ce2008-07-22 11:18:07 -04003114 /* add one reference for the caller */
3115 atomic_inc(&exists->refs);
3116 spin_unlock(&tree->buffer_lock);
Miao Xie19fe0a82010-10-26 20:57:29 -04003117 radix_tree_preload_end();
Chris Mason6af118ce2008-07-22 11:18:07 -04003118 goto free_eb;
3119 }
Chris Mason6af118ce2008-07-22 11:18:07 -04003120 /* add one reference for the tree */
3121 atomic_inc(&eb->refs);
Yan, Zhengf044ba72010-02-04 08:46:56 +00003122 spin_unlock(&tree->buffer_lock);
Miao Xie19fe0a82010-10-26 20:57:29 -04003123 radix_tree_preload_end();
Chris Masoneb14ab82011-02-10 12:35:00 -05003124
3125 /*
3126 * there is a race where release page may have
3127 * tried to find this extent buffer in the radix
3128 * but failed. It will tell the VM it is safe to
3129 * reclaim the, and it will clear the page private bit.
3130 * We must make sure to set the page private bit properly
3131 * after the extent buffer is in the radix tree so
3132 * it doesn't get lost
3133 */
3134 set_page_extent_mapped(eb->first_page);
3135 set_page_extent_head(eb->first_page, eb->len);
3136 if (!page0)
3137 unlock_page(eb->first_page);
Chris Masond1310b22008-01-24 16:13:08 -05003138 return eb;
3139
Chris Mason6af118ce2008-07-22 11:18:07 -04003140free_eb:
Chris Masoneb14ab82011-02-10 12:35:00 -05003141 if (eb->first_page && !page0)
3142 unlock_page(eb->first_page);
3143
Chris Masond1310b22008-01-24 16:13:08 -05003144 if (!atomic_dec_and_test(&eb->refs))
Chris Mason6af118ce2008-07-22 11:18:07 -04003145 return exists;
Miao Xie897ca6e2010-10-26 20:57:29 -04003146 btrfs_release_extent_buffer(eb);
Chris Mason6af118ce2008-07-22 11:18:07 -04003147 return exists;
Chris Masond1310b22008-01-24 16:13:08 -05003148}
Chris Masond1310b22008-01-24 16:13:08 -05003149
3150struct extent_buffer *find_extent_buffer(struct extent_io_tree *tree,
David Sterbaf09d1f62011-04-21 01:08:01 +02003151 u64 start, unsigned long len)
Chris Masond1310b22008-01-24 16:13:08 -05003152{
Chris Masond1310b22008-01-24 16:13:08 -05003153 struct extent_buffer *eb;
Chris Masond1310b22008-01-24 16:13:08 -05003154
Miao Xie19fe0a82010-10-26 20:57:29 -04003155 rcu_read_lock();
3156 eb = radix_tree_lookup(&tree->buffer, start >> PAGE_CACHE_SHIFT);
3157 if (eb && atomic_inc_not_zero(&eb->refs)) {
3158 rcu_read_unlock();
Josef Bacik0f9dd462008-09-23 13:14:11 -04003159 mark_page_accessed(eb->first_page);
Miao Xie19fe0a82010-10-26 20:57:29 -04003160 return eb;
3161 }
3162 rcu_read_unlock();
Josef Bacik0f9dd462008-09-23 13:14:11 -04003163
Miao Xie19fe0a82010-10-26 20:57:29 -04003164 return NULL;
Chris Masond1310b22008-01-24 16:13:08 -05003165}
Chris Masond1310b22008-01-24 16:13:08 -05003166
3167void free_extent_buffer(struct extent_buffer *eb)
3168{
Chris Masond1310b22008-01-24 16:13:08 -05003169 if (!eb)
3170 return;
3171
3172 if (!atomic_dec_and_test(&eb->refs))
3173 return;
3174
Chris Mason6af118ce2008-07-22 11:18:07 -04003175 WARN_ON(1);
Chris Masond1310b22008-01-24 16:13:08 -05003176}
Chris Masond1310b22008-01-24 16:13:08 -05003177
3178int clear_extent_buffer_dirty(struct extent_io_tree *tree,
3179 struct extent_buffer *eb)
3180{
Chris Masond1310b22008-01-24 16:13:08 -05003181 unsigned long i;
3182 unsigned long num_pages;
3183 struct page *page;
3184
Chris Masond1310b22008-01-24 16:13:08 -05003185 num_pages = num_extent_pages(eb->start, eb->len);
3186
3187 for (i = 0; i < num_pages; i++) {
3188 page = extent_buffer_page(eb, i);
Chris Masonb9473432009-03-13 11:00:37 -04003189 if (!PageDirty(page))
Chris Masond2c3f4f2008-11-19 12:44:22 -05003190 continue;
3191
Chris Masona61e6f22008-07-22 11:18:08 -04003192 lock_page(page);
Chris Masoneb14ab82011-02-10 12:35:00 -05003193 WARN_ON(!PagePrivate(page));
3194
3195 set_page_extent_mapped(page);
Chris Masond1310b22008-01-24 16:13:08 -05003196 if (i == 0)
3197 set_page_extent_head(page, eb->len);
Chris Masond1310b22008-01-24 16:13:08 -05003198
Chris Masond1310b22008-01-24 16:13:08 -05003199 clear_page_dirty_for_io(page);
Sven Wegener0ee0fda2008-07-30 16:54:26 -04003200 spin_lock_irq(&page->mapping->tree_lock);
Chris Masond1310b22008-01-24 16:13:08 -05003201 if (!PageDirty(page)) {
3202 radix_tree_tag_clear(&page->mapping->page_tree,
3203 page_index(page),
3204 PAGECACHE_TAG_DIRTY);
3205 }
Sven Wegener0ee0fda2008-07-30 16:54:26 -04003206 spin_unlock_irq(&page->mapping->tree_lock);
Chris Masona61e6f22008-07-22 11:18:08 -04003207 unlock_page(page);
Chris Masond1310b22008-01-24 16:13:08 -05003208 }
3209 return 0;
3210}
Chris Masond1310b22008-01-24 16:13:08 -05003211
Chris Masond1310b22008-01-24 16:13:08 -05003212int set_extent_buffer_dirty(struct extent_io_tree *tree,
3213 struct extent_buffer *eb)
3214{
3215 unsigned long i;
3216 unsigned long num_pages;
Chris Masonb9473432009-03-13 11:00:37 -04003217 int was_dirty = 0;
Chris Masond1310b22008-01-24 16:13:08 -05003218
Chris Masonb9473432009-03-13 11:00:37 -04003219 was_dirty = test_and_set_bit(EXTENT_BUFFER_DIRTY, &eb->bflags);
Chris Masond1310b22008-01-24 16:13:08 -05003220 num_pages = num_extent_pages(eb->start, eb->len);
Chris Masonb9473432009-03-13 11:00:37 -04003221 for (i = 0; i < num_pages; i++)
Chris Masond1310b22008-01-24 16:13:08 -05003222 __set_page_dirty_nobuffers(extent_buffer_page(eb, i));
Chris Masonb9473432009-03-13 11:00:37 -04003223 return was_dirty;
Chris Masond1310b22008-01-24 16:13:08 -05003224}
Chris Masond1310b22008-01-24 16:13:08 -05003225
Chris Mason19b6caf2011-07-25 06:50:50 -04003226static int __eb_straddles_pages(u64 start, u64 len)
3227{
3228 if (len < PAGE_CACHE_SIZE)
3229 return 1;
3230 if (start & (PAGE_CACHE_SIZE - 1))
3231 return 1;
3232 if ((start + len) & (PAGE_CACHE_SIZE - 1))
3233 return 1;
3234 return 0;
3235}
3236
3237static int eb_straddles_pages(struct extent_buffer *eb)
3238{
3239 return __eb_straddles_pages(eb->start, eb->len);
3240}
3241
Chris Mason1259ab72008-05-12 13:39:03 -04003242int clear_extent_buffer_uptodate(struct extent_io_tree *tree,
Josef Bacik2ac55d42010-02-03 19:33:23 +00003243 struct extent_buffer *eb,
3244 struct extent_state **cached_state)
Chris Mason1259ab72008-05-12 13:39:03 -04003245{
3246 unsigned long i;
3247 struct page *page;
3248 unsigned long num_pages;
3249
3250 num_pages = num_extent_pages(eb->start, eb->len);
Chris Masonb4ce94d2009-02-04 09:25:08 -05003251 clear_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
Chris Mason1259ab72008-05-12 13:39:03 -04003252
Chris Mason19b6caf2011-07-25 06:50:50 -04003253 if (eb_straddles_pages(eb)) {
3254 clear_extent_uptodate(tree, eb->start, eb->start + eb->len - 1,
3255 cached_state, GFP_NOFS);
3256 }
Chris Mason1259ab72008-05-12 13:39:03 -04003257 for (i = 0; i < num_pages; i++) {
3258 page = extent_buffer_page(eb, i);
Chris Mason33958dc2008-07-30 10:29:12 -04003259 if (page)
3260 ClearPageUptodate(page);
Chris Mason1259ab72008-05-12 13:39:03 -04003261 }
3262 return 0;
3263}
3264
Chris Masond1310b22008-01-24 16:13:08 -05003265int set_extent_buffer_uptodate(struct extent_io_tree *tree,
3266 struct extent_buffer *eb)
3267{
3268 unsigned long i;
3269 struct page *page;
3270 unsigned long num_pages;
3271
3272 num_pages = num_extent_pages(eb->start, eb->len);
3273
Chris Mason19b6caf2011-07-25 06:50:50 -04003274 if (eb_straddles_pages(eb)) {
3275 set_extent_uptodate(tree, eb->start, eb->start + eb->len - 1,
3276 NULL, GFP_NOFS);
3277 }
Chris Masond1310b22008-01-24 16:13:08 -05003278 for (i = 0; i < num_pages; i++) {
3279 page = extent_buffer_page(eb, i);
3280 if ((i == 0 && (eb->start & (PAGE_CACHE_SIZE - 1))) ||
3281 ((i == num_pages - 1) &&
3282 ((eb->start + eb->len) & (PAGE_CACHE_SIZE - 1)))) {
3283 check_page_uptodate(tree, page);
3284 continue;
3285 }
3286 SetPageUptodate(page);
3287 }
3288 return 0;
3289}
Chris Masond1310b22008-01-24 16:13:08 -05003290
Chris Masonce9adaa2008-04-09 16:28:12 -04003291int extent_range_uptodate(struct extent_io_tree *tree,
3292 u64 start, u64 end)
3293{
3294 struct page *page;
3295 int ret;
3296 int pg_uptodate = 1;
3297 int uptodate;
3298 unsigned long index;
3299
Chris Mason19b6caf2011-07-25 06:50:50 -04003300 if (__eb_straddles_pages(start, end - start + 1)) {
3301 ret = test_range_bit(tree, start, end,
3302 EXTENT_UPTODATE, 1, NULL);
3303 if (ret)
3304 return 1;
3305 }
Chris Masond3977122009-01-05 21:25:51 -05003306 while (start <= end) {
Chris Masonce9adaa2008-04-09 16:28:12 -04003307 index = start >> PAGE_CACHE_SHIFT;
3308 page = find_get_page(tree->mapping, index);
3309 uptodate = PageUptodate(page);
3310 page_cache_release(page);
3311 if (!uptodate) {
3312 pg_uptodate = 0;
3313 break;
3314 }
3315 start += PAGE_CACHE_SIZE;
3316 }
3317 return pg_uptodate;
3318}
3319
Chris Masond1310b22008-01-24 16:13:08 -05003320int extent_buffer_uptodate(struct extent_io_tree *tree,
Josef Bacik2ac55d42010-02-03 19:33:23 +00003321 struct extent_buffer *eb,
3322 struct extent_state *cached_state)
Chris Masond1310b22008-01-24 16:13:08 -05003323{
Chris Mason728131d2008-04-09 16:28:12 -04003324 int ret = 0;
Chris Masonce9adaa2008-04-09 16:28:12 -04003325 unsigned long num_pages;
3326 unsigned long i;
Chris Mason728131d2008-04-09 16:28:12 -04003327 struct page *page;
3328 int pg_uptodate = 1;
3329
Chris Masonb4ce94d2009-02-04 09:25:08 -05003330 if (test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags))
Chris Mason42352982008-04-28 16:40:52 -04003331 return 1;
Chris Mason728131d2008-04-09 16:28:12 -04003332
Chris Mason19b6caf2011-07-25 06:50:50 -04003333 if (eb_straddles_pages(eb)) {
3334 ret = test_range_bit(tree, eb->start, eb->start + eb->len - 1,
3335 EXTENT_UPTODATE, 1, cached_state);
3336 if (ret)
3337 return ret;
3338 }
Chris Mason728131d2008-04-09 16:28:12 -04003339
3340 num_pages = num_extent_pages(eb->start, eb->len);
3341 for (i = 0; i < num_pages; i++) {
3342 page = extent_buffer_page(eb, i);
3343 if (!PageUptodate(page)) {
3344 pg_uptodate = 0;
3345 break;
3346 }
3347 }
Chris Mason42352982008-04-28 16:40:52 -04003348 return pg_uptodate;
Chris Masond1310b22008-01-24 16:13:08 -05003349}
Chris Masond1310b22008-01-24 16:13:08 -05003350
3351int read_extent_buffer_pages(struct extent_io_tree *tree,
3352 struct extent_buffer *eb,
Chris Masona86c12c2008-02-07 10:50:54 -05003353 u64 start, int wait,
Chris Masonf1885912008-04-09 16:28:12 -04003354 get_extent_t *get_extent, int mirror_num)
Chris Masond1310b22008-01-24 16:13:08 -05003355{
3356 unsigned long i;
3357 unsigned long start_i;
3358 struct page *page;
3359 int err;
3360 int ret = 0;
Chris Masonce9adaa2008-04-09 16:28:12 -04003361 int locked_pages = 0;
3362 int all_uptodate = 1;
3363 int inc_all_pages = 0;
Chris Masond1310b22008-01-24 16:13:08 -05003364 unsigned long num_pages;
Chris Masona86c12c2008-02-07 10:50:54 -05003365 struct bio *bio = NULL;
Chris Masonc8b97812008-10-29 14:49:59 -04003366 unsigned long bio_flags = 0;
Chris Masona86c12c2008-02-07 10:50:54 -05003367
Chris Masonb4ce94d2009-02-04 09:25:08 -05003368 if (test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags))
Chris Masond1310b22008-01-24 16:13:08 -05003369 return 0;
3370
Chris Mason19b6caf2011-07-25 06:50:50 -04003371 if (eb_straddles_pages(eb)) {
3372 if (test_range_bit(tree, eb->start, eb->start + eb->len - 1,
3373 EXTENT_UPTODATE, 1, NULL)) {
3374 return 0;
3375 }
Chris Masond1310b22008-01-24 16:13:08 -05003376 }
3377
3378 if (start) {
3379 WARN_ON(start < eb->start);
3380 start_i = (start >> PAGE_CACHE_SHIFT) -
3381 (eb->start >> PAGE_CACHE_SHIFT);
3382 } else {
3383 start_i = 0;
3384 }
3385
3386 num_pages = num_extent_pages(eb->start, eb->len);
3387 for (i = start_i; i < num_pages; i++) {
3388 page = extent_buffer_page(eb, i);
Chris Masond1310b22008-01-24 16:13:08 -05003389 if (!wait) {
David Woodhouse2db04962008-08-07 11:19:43 -04003390 if (!trylock_page(page))
Chris Masonce9adaa2008-04-09 16:28:12 -04003391 goto unlock_exit;
Chris Masond1310b22008-01-24 16:13:08 -05003392 } else {
3393 lock_page(page);
3394 }
Chris Masonce9adaa2008-04-09 16:28:12 -04003395 locked_pages++;
Chris Masond3977122009-01-05 21:25:51 -05003396 if (!PageUptodate(page))
Chris Masonce9adaa2008-04-09 16:28:12 -04003397 all_uptodate = 0;
Chris Masonce9adaa2008-04-09 16:28:12 -04003398 }
3399 if (all_uptodate) {
3400 if (start_i == 0)
Chris Masonb4ce94d2009-02-04 09:25:08 -05003401 set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
Chris Masonce9adaa2008-04-09 16:28:12 -04003402 goto unlock_exit;
3403 }
3404
3405 for (i = start_i; i < num_pages; i++) {
3406 page = extent_buffer_page(eb, i);
Chris Masoneb14ab82011-02-10 12:35:00 -05003407
3408 WARN_ON(!PagePrivate(page));
3409
3410 set_page_extent_mapped(page);
3411 if (i == 0)
3412 set_page_extent_head(page, eb->len);
3413
Chris Masonce9adaa2008-04-09 16:28:12 -04003414 if (inc_all_pages)
3415 page_cache_get(page);
3416 if (!PageUptodate(page)) {
3417 if (start_i == 0)
3418 inc_all_pages = 1;
Chris Masonf1885912008-04-09 16:28:12 -04003419 ClearPageError(page);
Chris Masona86c12c2008-02-07 10:50:54 -05003420 err = __extent_read_full_page(tree, page,
Chris Masonf1885912008-04-09 16:28:12 -04003421 get_extent, &bio,
Chris Masonc8b97812008-10-29 14:49:59 -04003422 mirror_num, &bio_flags);
Chris Masond3977122009-01-05 21:25:51 -05003423 if (err)
Chris Masond1310b22008-01-24 16:13:08 -05003424 ret = err;
Chris Masond1310b22008-01-24 16:13:08 -05003425 } else {
3426 unlock_page(page);
3427 }
3428 }
3429
Chris Masona86c12c2008-02-07 10:50:54 -05003430 if (bio)
Chris Masonc8b97812008-10-29 14:49:59 -04003431 submit_one_bio(READ, bio, mirror_num, bio_flags);
Chris Masona86c12c2008-02-07 10:50:54 -05003432
Chris Masond3977122009-01-05 21:25:51 -05003433 if (ret || !wait)
Chris Masond1310b22008-01-24 16:13:08 -05003434 return ret;
Chris Masond3977122009-01-05 21:25:51 -05003435
Chris Masond1310b22008-01-24 16:13:08 -05003436 for (i = start_i; i < num_pages; i++) {
3437 page = extent_buffer_page(eb, i);
3438 wait_on_page_locked(page);
Chris Masond3977122009-01-05 21:25:51 -05003439 if (!PageUptodate(page))
Chris Masond1310b22008-01-24 16:13:08 -05003440 ret = -EIO;
Chris Masond1310b22008-01-24 16:13:08 -05003441 }
Chris Masond3977122009-01-05 21:25:51 -05003442
Chris Masond1310b22008-01-24 16:13:08 -05003443 if (!ret)
Chris Masonb4ce94d2009-02-04 09:25:08 -05003444 set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
Chris Masond1310b22008-01-24 16:13:08 -05003445 return ret;
Chris Masonce9adaa2008-04-09 16:28:12 -04003446
3447unlock_exit:
3448 i = start_i;
Chris Masond3977122009-01-05 21:25:51 -05003449 while (locked_pages > 0) {
Chris Masonce9adaa2008-04-09 16:28:12 -04003450 page = extent_buffer_page(eb, i);
3451 i++;
3452 unlock_page(page);
3453 locked_pages--;
3454 }
3455 return ret;
Chris Masond1310b22008-01-24 16:13:08 -05003456}
Chris Masond1310b22008-01-24 16:13:08 -05003457
3458void read_extent_buffer(struct extent_buffer *eb, void *dstv,
3459 unsigned long start,
3460 unsigned long len)
3461{
3462 size_t cur;
3463 size_t offset;
3464 struct page *page;
3465 char *kaddr;
3466 char *dst = (char *)dstv;
3467 size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1);
3468 unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT;
Chris Masond1310b22008-01-24 16:13:08 -05003469
3470 WARN_ON(start > eb->len);
3471 WARN_ON(start + len > eb->start + eb->len);
3472
3473 offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1);
3474
Chris Masond3977122009-01-05 21:25:51 -05003475 while (len > 0) {
Chris Masond1310b22008-01-24 16:13:08 -05003476 page = extent_buffer_page(eb, i);
Chris Masond1310b22008-01-24 16:13:08 -05003477
3478 cur = min(len, (PAGE_CACHE_SIZE - offset));
Chris Masona6591712011-07-19 12:04:14 -04003479 kaddr = page_address(page);
Chris Masond1310b22008-01-24 16:13:08 -05003480 memcpy(dst, kaddr + offset, cur);
Chris Masond1310b22008-01-24 16:13:08 -05003481
3482 dst += cur;
3483 len -= cur;
3484 offset = 0;
3485 i++;
3486 }
3487}
Chris Masond1310b22008-01-24 16:13:08 -05003488
3489int map_private_extent_buffer(struct extent_buffer *eb, unsigned long start,
Chris Masona6591712011-07-19 12:04:14 -04003490 unsigned long min_len, char **map,
Chris Masond1310b22008-01-24 16:13:08 -05003491 unsigned long *map_start,
Chris Masona6591712011-07-19 12:04:14 -04003492 unsigned long *map_len)
Chris Masond1310b22008-01-24 16:13:08 -05003493{
3494 size_t offset = start & (PAGE_CACHE_SIZE - 1);
3495 char *kaddr;
3496 struct page *p;
3497 size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1);
3498 unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT;
3499 unsigned long end_i = (start_offset + start + min_len - 1) >>
3500 PAGE_CACHE_SHIFT;
3501
3502 if (i != end_i)
3503 return -EINVAL;
3504
3505 if (i == 0) {
3506 offset = start_offset;
3507 *map_start = 0;
3508 } else {
3509 offset = 0;
3510 *map_start = ((u64)i << PAGE_CACHE_SHIFT) - start_offset;
3511 }
Chris Masond3977122009-01-05 21:25:51 -05003512
Chris Masond1310b22008-01-24 16:13:08 -05003513 if (start + min_len > eb->len) {
Chris Masond3977122009-01-05 21:25:51 -05003514 printk(KERN_ERR "btrfs bad mapping eb start %llu len %lu, "
3515 "wanted %lu %lu\n", (unsigned long long)eb->start,
3516 eb->len, start, min_len);
Chris Masond1310b22008-01-24 16:13:08 -05003517 WARN_ON(1);
Josef Bacik850265332011-03-15 14:52:12 -04003518 return -EINVAL;
Chris Masond1310b22008-01-24 16:13:08 -05003519 }
3520
3521 p = extent_buffer_page(eb, i);
Chris Masona6591712011-07-19 12:04:14 -04003522 kaddr = page_address(p);
Chris Masond1310b22008-01-24 16:13:08 -05003523 *map = kaddr + offset;
3524 *map_len = PAGE_CACHE_SIZE - offset;
3525 return 0;
3526}
Chris Masond1310b22008-01-24 16:13:08 -05003527
Chris Masond1310b22008-01-24 16:13:08 -05003528int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv,
3529 unsigned long start,
3530 unsigned long len)
3531{
3532 size_t cur;
3533 size_t offset;
3534 struct page *page;
3535 char *kaddr;
3536 char *ptr = (char *)ptrv;
3537 size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1);
3538 unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT;
3539 int ret = 0;
3540
3541 WARN_ON(start > eb->len);
3542 WARN_ON(start + len > eb->start + eb->len);
3543
3544 offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1);
3545
Chris Masond3977122009-01-05 21:25:51 -05003546 while (len > 0) {
Chris Masond1310b22008-01-24 16:13:08 -05003547 page = extent_buffer_page(eb, i);
Chris Masond1310b22008-01-24 16:13:08 -05003548
3549 cur = min(len, (PAGE_CACHE_SIZE - offset));
3550
Chris Masona6591712011-07-19 12:04:14 -04003551 kaddr = page_address(page);
Chris Masond1310b22008-01-24 16:13:08 -05003552 ret = memcmp(ptr, kaddr + offset, cur);
Chris Masond1310b22008-01-24 16:13:08 -05003553 if (ret)
3554 break;
3555
3556 ptr += cur;
3557 len -= cur;
3558 offset = 0;
3559 i++;
3560 }
3561 return ret;
3562}
Chris Masond1310b22008-01-24 16:13:08 -05003563
3564void write_extent_buffer(struct extent_buffer *eb, const void *srcv,
3565 unsigned long start, unsigned long len)
3566{
3567 size_t cur;
3568 size_t offset;
3569 struct page *page;
3570 char *kaddr;
3571 char *src = (char *)srcv;
3572 size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1);
3573 unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT;
3574
3575 WARN_ON(start > eb->len);
3576 WARN_ON(start + len > eb->start + eb->len);
3577
3578 offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1);
3579
Chris Masond3977122009-01-05 21:25:51 -05003580 while (len > 0) {
Chris Masond1310b22008-01-24 16:13:08 -05003581 page = extent_buffer_page(eb, i);
3582 WARN_ON(!PageUptodate(page));
3583
3584 cur = min(len, PAGE_CACHE_SIZE - offset);
Chris Masona6591712011-07-19 12:04:14 -04003585 kaddr = page_address(page);
Chris Masond1310b22008-01-24 16:13:08 -05003586 memcpy(kaddr + offset, src, cur);
Chris Masond1310b22008-01-24 16:13:08 -05003587
3588 src += cur;
3589 len -= cur;
3590 offset = 0;
3591 i++;
3592 }
3593}
Chris Masond1310b22008-01-24 16:13:08 -05003594
3595void memset_extent_buffer(struct extent_buffer *eb, char c,
3596 unsigned long start, unsigned long len)
3597{
3598 size_t cur;
3599 size_t offset;
3600 struct page *page;
3601 char *kaddr;
3602 size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1);
3603 unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT;
3604
3605 WARN_ON(start > eb->len);
3606 WARN_ON(start + len > eb->start + eb->len);
3607
3608 offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1);
3609
Chris Masond3977122009-01-05 21:25:51 -05003610 while (len > 0) {
Chris Masond1310b22008-01-24 16:13:08 -05003611 page = extent_buffer_page(eb, i);
3612 WARN_ON(!PageUptodate(page));
3613
3614 cur = min(len, PAGE_CACHE_SIZE - offset);
Chris Masona6591712011-07-19 12:04:14 -04003615 kaddr = page_address(page);
Chris Masond1310b22008-01-24 16:13:08 -05003616 memset(kaddr + offset, c, cur);
Chris Masond1310b22008-01-24 16:13:08 -05003617
3618 len -= cur;
3619 offset = 0;
3620 i++;
3621 }
3622}
Chris Masond1310b22008-01-24 16:13:08 -05003623
3624void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,
3625 unsigned long dst_offset, unsigned long src_offset,
3626 unsigned long len)
3627{
3628 u64 dst_len = dst->len;
3629 size_t cur;
3630 size_t offset;
3631 struct page *page;
3632 char *kaddr;
3633 size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1);
3634 unsigned long i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT;
3635
3636 WARN_ON(src->len != dst_len);
3637
3638 offset = (start_offset + dst_offset) &
3639 ((unsigned long)PAGE_CACHE_SIZE - 1);
3640
Chris Masond3977122009-01-05 21:25:51 -05003641 while (len > 0) {
Chris Masond1310b22008-01-24 16:13:08 -05003642 page = extent_buffer_page(dst, i);
3643 WARN_ON(!PageUptodate(page));
3644
3645 cur = min(len, (unsigned long)(PAGE_CACHE_SIZE - offset));
3646
Chris Masona6591712011-07-19 12:04:14 -04003647 kaddr = page_address(page);
Chris Masond1310b22008-01-24 16:13:08 -05003648 read_extent_buffer(src, kaddr + offset, src_offset, cur);
Chris Masond1310b22008-01-24 16:13:08 -05003649
3650 src_offset += cur;
3651 len -= cur;
3652 offset = 0;
3653 i++;
3654 }
3655}
Chris Masond1310b22008-01-24 16:13:08 -05003656
3657static void move_pages(struct page *dst_page, struct page *src_page,
3658 unsigned long dst_off, unsigned long src_off,
3659 unsigned long len)
3660{
Chris Masona6591712011-07-19 12:04:14 -04003661 char *dst_kaddr = page_address(dst_page);
Chris Masond1310b22008-01-24 16:13:08 -05003662 if (dst_page == src_page) {
3663 memmove(dst_kaddr + dst_off, dst_kaddr + src_off, len);
3664 } else {
Chris Masona6591712011-07-19 12:04:14 -04003665 char *src_kaddr = page_address(src_page);
Chris Masond1310b22008-01-24 16:13:08 -05003666 char *p = dst_kaddr + dst_off + len;
3667 char *s = src_kaddr + src_off + len;
3668
3669 while (len--)
3670 *--p = *--s;
Chris Masond1310b22008-01-24 16:13:08 -05003671 }
Chris Masond1310b22008-01-24 16:13:08 -05003672}
3673
Sergei Trofimovich33872062011-04-11 21:52:52 +00003674static inline bool areas_overlap(unsigned long src, unsigned long dst, unsigned long len)
3675{
3676 unsigned long distance = (src > dst) ? src - dst : dst - src;
3677 return distance < len;
3678}
3679
Chris Masond1310b22008-01-24 16:13:08 -05003680static void copy_pages(struct page *dst_page, struct page *src_page,
3681 unsigned long dst_off, unsigned long src_off,
3682 unsigned long len)
3683{
Chris Masona6591712011-07-19 12:04:14 -04003684 char *dst_kaddr = page_address(dst_page);
Chris Masond1310b22008-01-24 16:13:08 -05003685 char *src_kaddr;
3686
Sergei Trofimovich33872062011-04-11 21:52:52 +00003687 if (dst_page != src_page) {
Chris Masona6591712011-07-19 12:04:14 -04003688 src_kaddr = page_address(src_page);
Sergei Trofimovich33872062011-04-11 21:52:52 +00003689 } else {
Chris Masond1310b22008-01-24 16:13:08 -05003690 src_kaddr = dst_kaddr;
Sergei Trofimovich33872062011-04-11 21:52:52 +00003691 BUG_ON(areas_overlap(src_off, dst_off, len));
3692 }
Chris Masond1310b22008-01-24 16:13:08 -05003693
3694 memcpy(dst_kaddr + dst_off, src_kaddr + src_off, len);
Chris Masond1310b22008-01-24 16:13:08 -05003695}
3696
3697void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
3698 unsigned long src_offset, unsigned long len)
3699{
3700 size_t cur;
3701 size_t dst_off_in_page;
3702 size_t src_off_in_page;
3703 size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1);
3704 unsigned long dst_i;
3705 unsigned long src_i;
3706
3707 if (src_offset + len > dst->len) {
Chris Masond3977122009-01-05 21:25:51 -05003708 printk(KERN_ERR "btrfs memmove bogus src_offset %lu move "
3709 "len %lu dst len %lu\n", src_offset, len, dst->len);
Chris Masond1310b22008-01-24 16:13:08 -05003710 BUG_ON(1);
3711 }
3712 if (dst_offset + len > dst->len) {
Chris Masond3977122009-01-05 21:25:51 -05003713 printk(KERN_ERR "btrfs memmove bogus dst_offset %lu move "
3714 "len %lu dst len %lu\n", dst_offset, len, dst->len);
Chris Masond1310b22008-01-24 16:13:08 -05003715 BUG_ON(1);
3716 }
3717
Chris Masond3977122009-01-05 21:25:51 -05003718 while (len > 0) {
Chris Masond1310b22008-01-24 16:13:08 -05003719 dst_off_in_page = (start_offset + dst_offset) &
3720 ((unsigned long)PAGE_CACHE_SIZE - 1);
3721 src_off_in_page = (start_offset + src_offset) &
3722 ((unsigned long)PAGE_CACHE_SIZE - 1);
3723
3724 dst_i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT;
3725 src_i = (start_offset + src_offset) >> PAGE_CACHE_SHIFT;
3726
3727 cur = min(len, (unsigned long)(PAGE_CACHE_SIZE -
3728 src_off_in_page));
3729 cur = min_t(unsigned long, cur,
3730 (unsigned long)(PAGE_CACHE_SIZE - dst_off_in_page));
3731
3732 copy_pages(extent_buffer_page(dst, dst_i),
3733 extent_buffer_page(dst, src_i),
3734 dst_off_in_page, src_off_in_page, cur);
3735
3736 src_offset += cur;
3737 dst_offset += cur;
3738 len -= cur;
3739 }
3740}
Chris Masond1310b22008-01-24 16:13:08 -05003741
3742void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
3743 unsigned long src_offset, unsigned long len)
3744{
3745 size_t cur;
3746 size_t dst_off_in_page;
3747 size_t src_off_in_page;
3748 unsigned long dst_end = dst_offset + len - 1;
3749 unsigned long src_end = src_offset + len - 1;
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) {
Chris Masond3977122009-01-05 21:25:51 -05003755 printk(KERN_ERR "btrfs memmove bogus src_offset %lu move "
3756 "len %lu len %lu\n", src_offset, len, dst->len);
Chris Masond1310b22008-01-24 16:13:08 -05003757 BUG_ON(1);
3758 }
3759 if (dst_offset + len > dst->len) {
Chris Masond3977122009-01-05 21:25:51 -05003760 printk(KERN_ERR "btrfs memmove bogus dst_offset %lu move "
3761 "len %lu len %lu\n", dst_offset, len, dst->len);
Chris Masond1310b22008-01-24 16:13:08 -05003762 BUG_ON(1);
3763 }
Sergei Trofimovich33872062011-04-11 21:52:52 +00003764 if (!areas_overlap(src_offset, dst_offset, len)) {
Chris Masond1310b22008-01-24 16:13:08 -05003765 memcpy_extent_buffer(dst, dst_offset, src_offset, len);
3766 return;
3767 }
Chris Masond3977122009-01-05 21:25:51 -05003768 while (len > 0) {
Chris Masond1310b22008-01-24 16:13:08 -05003769 dst_i = (start_offset + dst_end) >> PAGE_CACHE_SHIFT;
3770 src_i = (start_offset + src_end) >> PAGE_CACHE_SHIFT;
3771
3772 dst_off_in_page = (start_offset + dst_end) &
3773 ((unsigned long)PAGE_CACHE_SIZE - 1);
3774 src_off_in_page = (start_offset + src_end) &
3775 ((unsigned long)PAGE_CACHE_SIZE - 1);
3776
3777 cur = min_t(unsigned long, len, src_off_in_page + 1);
3778 cur = min(cur, dst_off_in_page + 1);
3779 move_pages(extent_buffer_page(dst, dst_i),
3780 extent_buffer_page(dst, src_i),
3781 dst_off_in_page - cur + 1,
3782 src_off_in_page - cur + 1, cur);
3783
3784 dst_end -= cur;
3785 src_end -= cur;
3786 len -= cur;
3787 }
3788}
Chris Mason6af118ce2008-07-22 11:18:07 -04003789
Miao Xie19fe0a82010-10-26 20:57:29 -04003790static inline void btrfs_release_extent_buffer_rcu(struct rcu_head *head)
3791{
3792 struct extent_buffer *eb =
3793 container_of(head, struct extent_buffer, rcu_head);
3794
3795 btrfs_release_extent_buffer(eb);
3796}
3797
Chris Mason6af118ce2008-07-22 11:18:07 -04003798int try_release_extent_buffer(struct extent_io_tree *tree, struct page *page)
3799{
3800 u64 start = page_offset(page);
3801 struct extent_buffer *eb;
3802 int ret = 1;
Chris Mason6af118ce2008-07-22 11:18:07 -04003803
3804 spin_lock(&tree->buffer_lock);
Miao Xie19fe0a82010-10-26 20:57:29 -04003805 eb = radix_tree_lookup(&tree->buffer, start >> PAGE_CACHE_SHIFT);
Chris Mason45f49bc2010-11-21 22:27:44 -05003806 if (!eb) {
3807 spin_unlock(&tree->buffer_lock);
3808 return ret;
3809 }
Chris Mason6af118ce2008-07-22 11:18:07 -04003810
Chris Masonb9473432009-03-13 11:00:37 -04003811 if (test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)) {
3812 ret = 0;
3813 goto out;
3814 }
Miao Xie897ca6e2010-10-26 20:57:29 -04003815
Miao Xie19fe0a82010-10-26 20:57:29 -04003816 /*
3817 * set @eb->refs to 0 if it is already 1, and then release the @eb.
3818 * Or go back.
3819 */
3820 if (atomic_cmpxchg(&eb->refs, 1, 0) != 1) {
3821 ret = 0;
3822 goto out;
3823 }
3824
3825 radix_tree_delete(&tree->buffer, start >> PAGE_CACHE_SHIFT);
Chris Mason6af118ce2008-07-22 11:18:07 -04003826out:
3827 spin_unlock(&tree->buffer_lock);
Miao Xie19fe0a82010-10-26 20:57:29 -04003828
3829 /* at this point we can safely release the extent buffer */
3830 if (atomic_read(&eb->refs) == 0)
3831 call_rcu(&eb->rcu_head, btrfs_release_extent_buffer_rcu);
Chris Mason6af118ce2008-07-22 11:18:07 -04003832 return ret;
3833}