blob: fa4ef18b66b150a975d4143288b1de699dc0ecf0 [file] [log] [blame]
Chris Mason6cbd5572007-06-12 09:07:21 -04001/*
2 * Copyright (C) 2007 Oracle. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
17 */
18
Chris Mason39279cc2007-06-12 06:35:45 -040019#include <linux/fs.h>
20#include <linux/pagemap.h>
21#include <linux/highmem.h>
22#include <linux/time.h>
23#include <linux/init.h>
24#include <linux/string.h>
Chris Mason39279cc2007-06-12 06:35:45 -040025#include <linux/backing-dev.h>
26#include <linux/mpage.h>
Christoph Hellwig2fe17c12011-01-14 13:07:43 +010027#include <linux/falloc.h>
Chris Mason39279cc2007-06-12 06:35:45 -040028#include <linux/swap.h>
29#include <linux/writeback.h>
30#include <linux/statfs.h>
31#include <linux/compat.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090032#include <linux/slab.h>
Chris Mason39279cc2007-06-12 06:35:45 -040033#include "ctree.h"
34#include "disk-io.h"
35#include "transaction.h"
36#include "btrfs_inode.h"
37#include "ioctl.h"
38#include "print-tree.h"
Chris Masone02119d2008-09-05 16:13:11 -040039#include "tree-log.h"
40#include "locking.h"
Jeff Mahoney12fa8ec2008-05-02 15:03:58 -040041#include "compat.h"
Chris Mason39279cc2007-06-12 06:35:45 -040042
Chris Mason4cb53002011-05-24 15:35:30 -040043/*
44 * when auto defrag is enabled we
45 * queue up these defrag structs to remember which
46 * inodes need defragging passes
47 */
48struct inode_defrag {
49 struct rb_node rb_node;
50 /* objectid */
51 u64 ino;
52 /*
53 * transid where the defrag was added, we search for
54 * extents newer than this
55 */
56 u64 transid;
57
58 /* root objectid */
59 u64 root;
60
61 /* last offset we were able to defrag */
62 u64 last_offset;
63
64 /* if we've wrapped around back to zero once already */
65 int cycled;
66};
67
68/* pop a record for an inode into the defrag tree. The lock
69 * must be held already
70 *
71 * If you're inserting a record for an older transid than an
72 * existing record, the transid already in the tree is lowered
73 *
74 * If an existing record is found the defrag item you
75 * pass in is freed
76 */
77static int __btrfs_add_inode_defrag(struct inode *inode,
78 struct inode_defrag *defrag)
79{
80 struct btrfs_root *root = BTRFS_I(inode)->root;
81 struct inode_defrag *entry;
82 struct rb_node **p;
83 struct rb_node *parent = NULL;
84
85 p = &root->fs_info->defrag_inodes.rb_node;
86 while (*p) {
87 parent = *p;
88 entry = rb_entry(parent, struct inode_defrag, rb_node);
89
90 if (defrag->ino < entry->ino)
91 p = &parent->rb_left;
92 else if (defrag->ino > entry->ino)
93 p = &parent->rb_right;
94 else {
95 /* if we're reinserting an entry for
96 * an old defrag run, make sure to
97 * lower the transid of our existing record
98 */
99 if (defrag->transid < entry->transid)
100 entry->transid = defrag->transid;
101 if (defrag->last_offset > entry->last_offset)
102 entry->last_offset = defrag->last_offset;
103 goto exists;
104 }
105 }
106 BTRFS_I(inode)->in_defrag = 1;
107 rb_link_node(&defrag->rb_node, parent, p);
108 rb_insert_color(&defrag->rb_node, &root->fs_info->defrag_inodes);
109 return 0;
110
111exists:
112 kfree(defrag);
113 return 0;
114
115}
116
117/*
118 * insert a defrag record for this inode if auto defrag is
119 * enabled
120 */
121int btrfs_add_inode_defrag(struct btrfs_trans_handle *trans,
122 struct inode *inode)
123{
124 struct btrfs_root *root = BTRFS_I(inode)->root;
125 struct inode_defrag *defrag;
126 int ret = 0;
127 u64 transid;
128
129 if (!btrfs_test_opt(root, AUTO_DEFRAG))
130 return 0;
131
David Sterba7841cb22011-05-31 18:07:27 +0200132 if (btrfs_fs_closing(root->fs_info))
Chris Mason4cb53002011-05-24 15:35:30 -0400133 return 0;
134
135 if (BTRFS_I(inode)->in_defrag)
136 return 0;
137
138 if (trans)
139 transid = trans->transid;
140 else
141 transid = BTRFS_I(inode)->root->last_trans;
142
143 defrag = kzalloc(sizeof(*defrag), GFP_NOFS);
144 if (!defrag)
145 return -ENOMEM;
146
David Sterbaa4689d22011-05-31 17:08:14 +0000147 defrag->ino = btrfs_ino(inode);
Chris Mason4cb53002011-05-24 15:35:30 -0400148 defrag->transid = transid;
149 defrag->root = root->root_key.objectid;
150
151 spin_lock(&root->fs_info->defrag_inodes_lock);
152 if (!BTRFS_I(inode)->in_defrag)
153 ret = __btrfs_add_inode_defrag(inode, defrag);
154 spin_unlock(&root->fs_info->defrag_inodes_lock);
155 return ret;
156}
157
158/*
159 * must be called with the defrag_inodes lock held
160 */
161struct inode_defrag *btrfs_find_defrag_inode(struct btrfs_fs_info *info, u64 ino,
162 struct rb_node **next)
163{
164 struct inode_defrag *entry = NULL;
165 struct rb_node *p;
166 struct rb_node *parent = NULL;
167
168 p = info->defrag_inodes.rb_node;
169 while (p) {
170 parent = p;
171 entry = rb_entry(parent, struct inode_defrag, rb_node);
172
173 if (ino < entry->ino)
174 p = parent->rb_left;
175 else if (ino > entry->ino)
176 p = parent->rb_right;
177 else
178 return entry;
179 }
180
181 if (next) {
182 while (parent && ino > entry->ino) {
183 parent = rb_next(parent);
184 entry = rb_entry(parent, struct inode_defrag, rb_node);
185 }
186 *next = parent;
187 }
188 return NULL;
189}
190
191/*
192 * run through the list of inodes in the FS that need
193 * defragging
194 */
195int btrfs_run_defrag_inodes(struct btrfs_fs_info *fs_info)
196{
197 struct inode_defrag *defrag;
198 struct btrfs_root *inode_root;
199 struct inode *inode;
200 struct rb_node *n;
201 struct btrfs_key key;
202 struct btrfs_ioctl_defrag_range_args range;
203 u64 first_ino = 0;
204 int num_defrag;
205 int defrag_batch = 1024;
206
207 memset(&range, 0, sizeof(range));
208 range.len = (u64)-1;
209
210 atomic_inc(&fs_info->defrag_running);
211 spin_lock(&fs_info->defrag_inodes_lock);
212 while(1) {
213 n = NULL;
214
215 /* find an inode to defrag */
216 defrag = btrfs_find_defrag_inode(fs_info, first_ino, &n);
217 if (!defrag) {
218 if (n)
219 defrag = rb_entry(n, struct inode_defrag, rb_node);
220 else if (first_ino) {
221 first_ino = 0;
222 continue;
223 } else {
224 break;
225 }
226 }
227
228 /* remove it from the rbtree */
229 first_ino = defrag->ino + 1;
230 rb_erase(&defrag->rb_node, &fs_info->defrag_inodes);
231
David Sterba7841cb22011-05-31 18:07:27 +0200232 if (btrfs_fs_closing(fs_info))
Chris Mason4cb53002011-05-24 15:35:30 -0400233 goto next_free;
234
235 spin_unlock(&fs_info->defrag_inodes_lock);
236
237 /* get the inode */
238 key.objectid = defrag->root;
239 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
240 key.offset = (u64)-1;
241 inode_root = btrfs_read_fs_root_no_name(fs_info, &key);
242 if (IS_ERR(inode_root))
243 goto next;
244
245 key.objectid = defrag->ino;
246 btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
247 key.offset = 0;
248
249 inode = btrfs_iget(fs_info->sb, &key, inode_root, NULL);
250 if (IS_ERR(inode))
251 goto next;
252
253 /* do a chunk of defrag */
254 BTRFS_I(inode)->in_defrag = 0;
255 range.start = defrag->last_offset;
256 num_defrag = btrfs_defrag_file(inode, NULL, &range, defrag->transid,
257 defrag_batch);
258 /*
259 * if we filled the whole defrag batch, there
260 * must be more work to do. Queue this defrag
261 * again
262 */
263 if (num_defrag == defrag_batch) {
264 defrag->last_offset = range.start;
265 __btrfs_add_inode_defrag(inode, defrag);
266 /*
267 * we don't want to kfree defrag, we added it back to
268 * the rbtree
269 */
270 defrag = NULL;
271 } else if (defrag->last_offset && !defrag->cycled) {
272 /*
273 * we didn't fill our defrag batch, but
274 * we didn't start at zero. Make sure we loop
275 * around to the start of the file.
276 */
277 defrag->last_offset = 0;
278 defrag->cycled = 1;
279 __btrfs_add_inode_defrag(inode, defrag);
280 defrag = NULL;
281 }
282
283 iput(inode);
284next:
285 spin_lock(&fs_info->defrag_inodes_lock);
286next_free:
287 kfree(defrag);
288 }
289 spin_unlock(&fs_info->defrag_inodes_lock);
290
291 atomic_dec(&fs_info->defrag_running);
292
293 /*
294 * during unmount, we use the transaction_wait queue to
295 * wait for the defragger to stop
296 */
297 wake_up(&fs_info->transaction_wait);
298 return 0;
299}
Chris Mason39279cc2007-06-12 06:35:45 -0400300
Chris Masond352ac62008-09-29 15:18:18 -0400301/* simple helper to fault in pages and copy. This should go away
302 * and be replaced with calls into generic code.
303 */
Chris Masond3977122009-01-05 21:25:51 -0500304static noinline int btrfs_copy_from_user(loff_t pos, int num_pages,
Josef Bacikd0215f32011-01-25 14:57:24 -0500305 size_t write_bytes,
Chris Masona1b32a52008-09-05 16:09:51 -0400306 struct page **prepared_pages,
Josef Bacik11c65dc2010-05-23 11:07:21 -0400307 struct iov_iter *i)
Chris Mason39279cc2007-06-12 06:35:45 -0400308{
Xin Zhong914ee292010-12-09 09:30:14 +0000309 size_t copied = 0;
Josef Bacikd0215f32011-01-25 14:57:24 -0500310 size_t total_copied = 0;
Josef Bacik11c65dc2010-05-23 11:07:21 -0400311 int pg = 0;
Chris Mason39279cc2007-06-12 06:35:45 -0400312 int offset = pos & (PAGE_CACHE_SIZE - 1);
313
Josef Bacik11c65dc2010-05-23 11:07:21 -0400314 while (write_bytes > 0) {
Chris Mason39279cc2007-06-12 06:35:45 -0400315 size_t count = min_t(size_t,
316 PAGE_CACHE_SIZE - offset, write_bytes);
Josef Bacik11c65dc2010-05-23 11:07:21 -0400317 struct page *page = prepared_pages[pg];
Xin Zhong914ee292010-12-09 09:30:14 +0000318 /*
319 * Copy data from userspace to the current page
320 *
321 * Disable pagefault to avoid recursive lock since
322 * the pages are already locked
323 */
324 pagefault_disable();
325 copied = iov_iter_copy_from_user_atomic(page, i, offset, count);
326 pagefault_enable();
Josef Bacik11c65dc2010-05-23 11:07:21 -0400327
Chris Mason39279cc2007-06-12 06:35:45 -0400328 /* Flush processor's dcache for this page */
329 flush_dcache_page(page);
Chris Mason31339ac2011-03-07 11:10:24 -0500330
331 /*
332 * if we get a partial write, we can end up with
333 * partially up to date pages. These add
334 * a lot of complexity, so make sure they don't
335 * happen by forcing this copy to be retried.
336 *
337 * The rest of the btrfs_file_write code will fall
338 * back to page at a time copies after we return 0.
339 */
340 if (!PageUptodate(page) && copied < count)
341 copied = 0;
342
Josef Bacik11c65dc2010-05-23 11:07:21 -0400343 iov_iter_advance(i, copied);
344 write_bytes -= copied;
Xin Zhong914ee292010-12-09 09:30:14 +0000345 total_copied += copied;
Chris Mason39279cc2007-06-12 06:35:45 -0400346
Xin Zhong914ee292010-12-09 09:30:14 +0000347 /* Return to btrfs_file_aio_write to fault page */
Josef Bacik9f570b82011-01-25 12:42:37 -0500348 if (unlikely(copied == 0))
Xin Zhong914ee292010-12-09 09:30:14 +0000349 break;
Josef Bacik11c65dc2010-05-23 11:07:21 -0400350
351 if (unlikely(copied < PAGE_CACHE_SIZE - offset)) {
352 offset += copied;
353 } else {
354 pg++;
355 offset = 0;
356 }
Chris Mason39279cc2007-06-12 06:35:45 -0400357 }
Xin Zhong914ee292010-12-09 09:30:14 +0000358 return total_copied;
Chris Mason39279cc2007-06-12 06:35:45 -0400359}
360
Chris Masond352ac62008-09-29 15:18:18 -0400361/*
362 * unlocks pages after btrfs_file_write is done with them
363 */
Josef Bacikbe1a12a2011-04-06 13:05:22 -0400364void btrfs_drop_pages(struct page **pages, size_t num_pages)
Chris Mason39279cc2007-06-12 06:35:45 -0400365{
366 size_t i;
367 for (i = 0; i < num_pages; i++) {
Chris Masond352ac62008-09-29 15:18:18 -0400368 /* page checked is some magic around finding pages that
369 * have been modified without going through btrfs_set_page_dirty
370 * clear it here
371 */
Chris Mason4a096752008-07-21 10:29:44 -0400372 ClearPageChecked(pages[i]);
Chris Mason39279cc2007-06-12 06:35:45 -0400373 unlock_page(pages[i]);
374 mark_page_accessed(pages[i]);
375 page_cache_release(pages[i]);
376 }
377}
378
Chris Masond352ac62008-09-29 15:18:18 -0400379/*
380 * after copy_from_user, pages need to be dirtied and we need to make
381 * sure holes are created between the current EOF and the start of
382 * any next extents (if required).
383 *
384 * this also makes the decision about creating an inline extent vs
385 * doing real data extents, marking pages dirty and delalloc as required.
386 */
Josef Bacikbe1a12a2011-04-06 13:05:22 -0400387int btrfs_dirty_pages(struct btrfs_root *root, struct inode *inode,
388 struct page **pages, size_t num_pages,
389 loff_t pos, size_t write_bytes,
390 struct extent_state **cached)
Chris Mason39279cc2007-06-12 06:35:45 -0400391{
Chris Mason39279cc2007-06-12 06:35:45 -0400392 int err = 0;
Chris Masona52d9a82007-08-27 16:49:44 -0400393 int i;
Chris Masondb945352007-10-15 16:15:53 -0400394 u64 num_bytes;
Chris Masona52d9a82007-08-27 16:49:44 -0400395 u64 start_pos;
396 u64 end_of_last_block;
397 u64 end_pos = pos + write_bytes;
398 loff_t isize = i_size_read(inode);
Chris Mason39279cc2007-06-12 06:35:45 -0400399
Chris Mason5f39d392007-10-15 16:14:19 -0400400 start_pos = pos & ~((u64)root->sectorsize - 1);
Chris Masondb945352007-10-15 16:15:53 -0400401 num_bytes = (write_bytes + pos - start_pos +
402 root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
Chris Mason39279cc2007-06-12 06:35:45 -0400403
Chris Masondb945352007-10-15 16:15:53 -0400404 end_of_last_block = start_pos + num_bytes - 1;
Josef Bacik2ac55d42010-02-03 19:33:23 +0000405 err = btrfs_set_extent_delalloc(inode, start_pos, end_of_last_block,
Josef Bacikbe1a12a2011-04-06 13:05:22 -0400406 cached);
Josef Bacikd0215f32011-01-25 14:57:24 -0500407 if (err)
408 return err;
Josef Bacik9ed74f22009-09-11 16:12:44 -0400409
Chris Masonc8b97812008-10-29 14:49:59 -0400410 for (i = 0; i < num_pages; i++) {
411 struct page *p = pages[i];
412 SetPageUptodate(p);
413 ClearPageChecked(p);
414 set_page_dirty(p);
Chris Masona52d9a82007-08-27 16:49:44 -0400415 }
Josef Bacik9f570b82011-01-25 12:42:37 -0500416
417 /*
418 * we've only changed i_size in ram, and we haven't updated
419 * the disk i_size. There is no need to log the inode
420 * at this time.
421 */
422 if (end_pos > isize)
Chris Masona52d9a82007-08-27 16:49:44 -0400423 i_size_write(inode, end_pos);
Yan, Zhenga22285a2010-05-16 10:48:46 -0400424 return 0;
Chris Mason39279cc2007-06-12 06:35:45 -0400425}
426
Chris Masond352ac62008-09-29 15:18:18 -0400427/*
428 * this drops all the extents in the cache that intersect the range
429 * [start, end]. Existing extents are split as required.
430 */
Zheng Yan5b21f2e2008-09-26 10:05:38 -0400431int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end,
432 int skip_pinned)
Chris Masona52d9a82007-08-27 16:49:44 -0400433{
434 struct extent_map *em;
Chris Mason3b951512008-04-17 11:29:12 -0400435 struct extent_map *split = NULL;
436 struct extent_map *split2 = NULL;
Chris Masona52d9a82007-08-27 16:49:44 -0400437 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
Yan39b56372008-02-15 10:40:50 -0500438 u64 len = end - start + 1;
Chris Mason3b951512008-04-17 11:29:12 -0400439 int ret;
440 int testend = 1;
Zheng Yan5b21f2e2008-09-26 10:05:38 -0400441 unsigned long flags;
Chris Masonc8b97812008-10-29 14:49:59 -0400442 int compressed = 0;
Chris Masona52d9a82007-08-27 16:49:44 -0400443
Chris Masone6dcd2d2008-07-17 12:53:50 -0400444 WARN_ON(end < start);
Chris Mason3b951512008-04-17 11:29:12 -0400445 if (end == (u64)-1) {
Yan39b56372008-02-15 10:40:50 -0500446 len = (u64)-1;
Chris Mason3b951512008-04-17 11:29:12 -0400447 testend = 0;
448 }
Chris Masond3977122009-01-05 21:25:51 -0500449 while (1) {
Chris Mason3b951512008-04-17 11:29:12 -0400450 if (!split)
David Sterba172ddd62011-04-21 00:48:27 +0200451 split = alloc_extent_map();
Chris Mason3b951512008-04-17 11:29:12 -0400452 if (!split2)
David Sterba172ddd62011-04-21 00:48:27 +0200453 split2 = alloc_extent_map();
Tsutomu Itohc26a9202011-02-14 00:45:29 +0000454 BUG_ON(!split || !split2);
Chris Mason3b951512008-04-17 11:29:12 -0400455
Chris Mason890871b2009-09-02 16:24:52 -0400456 write_lock(&em_tree->lock);
Yan39b56372008-02-15 10:40:50 -0500457 em = lookup_extent_mapping(em_tree, start, len);
Chris Masond1310b22008-01-24 16:13:08 -0500458 if (!em) {
Chris Mason890871b2009-09-02 16:24:52 -0400459 write_unlock(&em_tree->lock);
Chris Masona52d9a82007-08-27 16:49:44 -0400460 break;
Chris Masond1310b22008-01-24 16:13:08 -0500461 }
Zheng Yan5b21f2e2008-09-26 10:05:38 -0400462 flags = em->flags;
463 if (skip_pinned && test_bit(EXTENT_FLAG_PINNED, &em->flags)) {
Yan, Zheng55ef6892009-11-12 09:36:44 +0000464 if (testend && em->start + em->len >= start + len) {
Zheng Yan5b21f2e2008-09-26 10:05:38 -0400465 free_extent_map(em);
Chris Masona1ed8352009-09-11 12:27:37 -0400466 write_unlock(&em_tree->lock);
Zheng Yan5b21f2e2008-09-26 10:05:38 -0400467 break;
468 }
Yan, Zheng55ef6892009-11-12 09:36:44 +0000469 start = em->start + em->len;
470 if (testend)
Zheng Yan5b21f2e2008-09-26 10:05:38 -0400471 len = start + len - (em->start + em->len);
Zheng Yan5b21f2e2008-09-26 10:05:38 -0400472 free_extent_map(em);
Chris Masona1ed8352009-09-11 12:27:37 -0400473 write_unlock(&em_tree->lock);
Zheng Yan5b21f2e2008-09-26 10:05:38 -0400474 continue;
475 }
Chris Masonc8b97812008-10-29 14:49:59 -0400476 compressed = test_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
Chris Mason3ce7e672008-07-31 15:42:54 -0400477 clear_bit(EXTENT_FLAG_PINNED, &em->flags);
Chris Masona52d9a82007-08-27 16:49:44 -0400478 remove_extent_mapping(em_tree, em);
Chris Mason3b951512008-04-17 11:29:12 -0400479
480 if (em->block_start < EXTENT_MAP_LAST_BYTE &&
481 em->start < start) {
482 split->start = em->start;
483 split->len = start - em->start;
Yan Zhengff5b7ee2008-11-10 07:34:43 -0500484 split->orig_start = em->orig_start;
Chris Mason3b951512008-04-17 11:29:12 -0400485 split->block_start = em->block_start;
Chris Masonc8b97812008-10-29 14:49:59 -0400486
487 if (compressed)
488 split->block_len = em->block_len;
489 else
490 split->block_len = split->len;
491
Chris Mason3b951512008-04-17 11:29:12 -0400492 split->bdev = em->bdev;
Zheng Yan5b21f2e2008-09-26 10:05:38 -0400493 split->flags = flags;
Li Zefan261507a02010-12-17 14:21:50 +0800494 split->compress_type = em->compress_type;
Chris Mason3b951512008-04-17 11:29:12 -0400495 ret = add_extent_mapping(em_tree, split);
496 BUG_ON(ret);
497 free_extent_map(split);
498 split = split2;
499 split2 = NULL;
500 }
501 if (em->block_start < EXTENT_MAP_LAST_BYTE &&
502 testend && em->start + em->len > start + len) {
503 u64 diff = start + len - em->start;
504
505 split->start = start + len;
506 split->len = em->start + em->len - (start + len);
507 split->bdev = em->bdev;
Zheng Yan5b21f2e2008-09-26 10:05:38 -0400508 split->flags = flags;
Li Zefan261507a02010-12-17 14:21:50 +0800509 split->compress_type = em->compress_type;
Chris Mason3b951512008-04-17 11:29:12 -0400510
Chris Masonc8b97812008-10-29 14:49:59 -0400511 if (compressed) {
512 split->block_len = em->block_len;
513 split->block_start = em->block_start;
Chris Mason445a6942008-11-10 11:53:33 -0500514 split->orig_start = em->orig_start;
Chris Masonc8b97812008-10-29 14:49:59 -0400515 } else {
516 split->block_len = split->len;
517 split->block_start = em->block_start + diff;
Chris Mason445a6942008-11-10 11:53:33 -0500518 split->orig_start = split->start;
Chris Masonc8b97812008-10-29 14:49:59 -0400519 }
Chris Mason3b951512008-04-17 11:29:12 -0400520
521 ret = add_extent_mapping(em_tree, split);
522 BUG_ON(ret);
523 free_extent_map(split);
524 split = NULL;
525 }
Chris Mason890871b2009-09-02 16:24:52 -0400526 write_unlock(&em_tree->lock);
Chris Masond1310b22008-01-24 16:13:08 -0500527
Chris Masona52d9a82007-08-27 16:49:44 -0400528 /* once for us */
529 free_extent_map(em);
530 /* once for the tree*/
531 free_extent_map(em);
532 }
Chris Mason3b951512008-04-17 11:29:12 -0400533 if (split)
534 free_extent_map(split);
535 if (split2)
536 free_extent_map(split2);
Chris Masona52d9a82007-08-27 16:49:44 -0400537 return 0;
538}
539
Chris Mason39279cc2007-06-12 06:35:45 -0400540/*
541 * this is very complex, but the basic idea is to drop all extents
542 * in the range start - end. hint_block is filled in with a block number
543 * that would be a good hint to the block allocator for this file.
544 *
545 * If an extent intersects the range but is not entirely inside the range
546 * it is either truncated or split. Anything entirely inside the range
547 * is deleted from the tree.
548 */
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000549int btrfs_drop_extents(struct btrfs_trans_handle *trans, struct inode *inode,
550 u64 start, u64 end, u64 *hint_byte, int drop_cache)
Chris Mason39279cc2007-06-12 06:35:45 -0400551{
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000552 struct btrfs_root *root = BTRFS_I(inode)->root;
Chris Mason00f5c792007-11-30 10:09:33 -0500553 struct extent_buffer *leaf;
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000554 struct btrfs_file_extent_item *fi;
Chris Mason00f5c792007-11-30 10:09:33 -0500555 struct btrfs_path *path;
556 struct btrfs_key key;
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000557 struct btrfs_key new_key;
Li Zefan33345d012011-04-20 10:31:50 +0800558 u64 ino = btrfs_ino(inode);
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000559 u64 search_start = start;
560 u64 disk_bytenr = 0;
561 u64 num_bytes = 0;
562 u64 extent_offset = 0;
563 u64 extent_end = 0;
564 int del_nr = 0;
565 int del_slot = 0;
566 int extent_type;
Chris Masonccd467d2007-06-28 15:57:36 -0400567 int recow;
Chris Mason00f5c792007-11-30 10:09:33 -0500568 int ret;
Chris Mason39279cc2007-06-12 06:35:45 -0400569
Chris Masona1ed8352009-09-11 12:27:37 -0400570 if (drop_cache)
571 btrfs_drop_extent_cache(inode, start, end - 1, 0);
Chris Masona52d9a82007-08-27 16:49:44 -0400572
Chris Mason39279cc2007-06-12 06:35:45 -0400573 path = btrfs_alloc_path();
574 if (!path)
575 return -ENOMEM;
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000576
Chris Masond3977122009-01-05 21:25:51 -0500577 while (1) {
Chris Masonccd467d2007-06-28 15:57:36 -0400578 recow = 0;
Li Zefan33345d012011-04-20 10:31:50 +0800579 ret = btrfs_lookup_file_extent(trans, root, path, ino,
Chris Mason39279cc2007-06-12 06:35:45 -0400580 search_start, -1);
581 if (ret < 0)
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000582 break;
583 if (ret > 0 && path->slots[0] > 0 && search_start == start) {
584 leaf = path->nodes[0];
585 btrfs_item_key_to_cpu(leaf, &key, path->slots[0] - 1);
Li Zefan33345d012011-04-20 10:31:50 +0800586 if (key.objectid == ino &&
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000587 key.type == BTRFS_EXTENT_DATA_KEY)
588 path->slots[0]--;
Chris Mason39279cc2007-06-12 06:35:45 -0400589 }
Chris Mason8c2383c2007-06-18 09:57:58 -0400590 ret = 0;
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000591next_slot:
592 leaf = path->nodes[0];
593 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
594 BUG_ON(del_nr > 0);
595 ret = btrfs_next_leaf(root, path);
596 if (ret < 0)
597 break;
598 if (ret > 0) {
599 ret = 0;
600 break;
Chris Mason8c2383c2007-06-18 09:57:58 -0400601 }
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000602 leaf = path->nodes[0];
603 recow = 1;
604 }
605
606 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
Li Zefan33345d012011-04-20 10:31:50 +0800607 if (key.objectid > ino ||
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000608 key.type > BTRFS_EXTENT_DATA_KEY || key.offset >= end)
609 break;
610
611 fi = btrfs_item_ptr(leaf, path->slots[0],
612 struct btrfs_file_extent_item);
613 extent_type = btrfs_file_extent_type(leaf, fi);
614
615 if (extent_type == BTRFS_FILE_EXTENT_REG ||
616 extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
617 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
618 num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi);
619 extent_offset = btrfs_file_extent_offset(leaf, fi);
620 extent_end = key.offset +
621 btrfs_file_extent_num_bytes(leaf, fi);
622 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
623 extent_end = key.offset +
624 btrfs_file_extent_inline_len(leaf, fi);
Chris Mason8c2383c2007-06-18 09:57:58 -0400625 } else {
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000626 WARN_ON(1);
Chris Mason8c2383c2007-06-18 09:57:58 -0400627 extent_end = search_start;
Chris Mason39279cc2007-06-12 06:35:45 -0400628 }
629
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000630 if (extent_end <= search_start) {
631 path->slots[0]++;
Chris Mason8c2383c2007-06-18 09:57:58 -0400632 goto next_slot;
Chris Mason39279cc2007-06-12 06:35:45 -0400633 }
634
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000635 search_start = max(key.offset, start);
636 if (recow) {
David Sterbab3b4aa72011-04-21 01:20:15 +0200637 btrfs_release_path(path);
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000638 continue;
Chris Mason39279cc2007-06-12 06:35:45 -0400639 }
Chris Mason771ed682008-11-06 22:02:51 -0500640
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000641 /*
642 * | - range to drop - |
643 * | -------- extent -------- |
644 */
645 if (start > key.offset && end < extent_end) {
646 BUG_ON(del_nr > 0);
647 BUG_ON(extent_type == BTRFS_FILE_EXTENT_INLINE);
648
649 memcpy(&new_key, &key, sizeof(new_key));
650 new_key.offset = start;
651 ret = btrfs_duplicate_item(trans, root, path,
652 &new_key);
653 if (ret == -EAGAIN) {
David Sterbab3b4aa72011-04-21 01:20:15 +0200654 btrfs_release_path(path);
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000655 continue;
656 }
657 if (ret < 0)
658 break;
Chris Mason8c2383c2007-06-18 09:57:58 -0400659
Chris Mason5f39d392007-10-15 16:14:19 -0400660 leaf = path->nodes[0];
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000661 fi = btrfs_item_ptr(leaf, path->slots[0] - 1,
662 struct btrfs_file_extent_item);
663 btrfs_set_file_extent_num_bytes(leaf, fi,
664 start - key.offset);
Chris Mason39279cc2007-06-12 06:35:45 -0400665
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000666 fi = btrfs_item_ptr(leaf, path->slots[0],
667 struct btrfs_file_extent_item);
Chris Masonc8b97812008-10-29 14:49:59 -0400668
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000669 extent_offset += start - key.offset;
670 btrfs_set_file_extent_offset(leaf, fi, extent_offset);
671 btrfs_set_file_extent_num_bytes(leaf, fi,
672 extent_end - start);
673 btrfs_mark_buffer_dirty(leaf);
Chris Masondb945352007-10-15 16:15:53 -0400674
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000675 if (disk_bytenr > 0) {
676 ret = btrfs_inc_extent_ref(trans, root,
677 disk_bytenr, num_bytes, 0,
678 root->root_key.objectid,
679 new_key.objectid,
680 start - extent_offset);
Zheng Yan31840ae2008-09-23 13:14:14 -0400681 BUG_ON(ret);
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000682 *hint_byte = disk_bytenr;
Zheng Yan31840ae2008-09-23 13:14:14 -0400683 }
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000684 key.offset = start;
685 }
686 /*
687 * | ---- range to drop ----- |
688 * | -------- extent -------- |
689 */
690 if (start <= key.offset && end < extent_end) {
691 BUG_ON(extent_type == BTRFS_FILE_EXTENT_INLINE);
692
693 memcpy(&new_key, &key, sizeof(new_key));
694 new_key.offset = end;
695 btrfs_set_item_key_safe(trans, root, path, &new_key);
696
697 extent_offset += end - key.offset;
698 btrfs_set_file_extent_offset(leaf, fi, extent_offset);
699 btrfs_set_file_extent_num_bytes(leaf, fi,
700 extent_end - end);
701 btrfs_mark_buffer_dirty(leaf);
702 if (disk_bytenr > 0) {
703 inode_sub_bytes(inode, end - key.offset);
704 *hint_byte = disk_bytenr;
705 }
706 break;
Zheng Yan31840ae2008-09-23 13:14:14 -0400707 }
708
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000709 search_start = extent_end;
710 /*
711 * | ---- range to drop ----- |
712 * | -------- extent -------- |
713 */
714 if (start > key.offset && end >= extent_end) {
715 BUG_ON(del_nr > 0);
716 BUG_ON(extent_type == BTRFS_FILE_EXTENT_INLINE);
717
718 btrfs_set_file_extent_num_bytes(leaf, fi,
719 start - key.offset);
720 btrfs_mark_buffer_dirty(leaf);
721 if (disk_bytenr > 0) {
722 inode_sub_bytes(inode, extent_end - start);
723 *hint_byte = disk_bytenr;
724 }
725 if (end == extent_end)
726 break;
727
728 path->slots[0]++;
729 goto next_slot;
Chris Mason39279cc2007-06-12 06:35:45 -0400730 }
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000731
732 /*
733 * | ---- range to drop ----- |
734 * | ------ extent ------ |
735 */
736 if (start <= key.offset && end >= extent_end) {
737 if (del_nr == 0) {
738 del_slot = path->slots[0];
739 del_nr = 1;
740 } else {
741 BUG_ON(del_slot + del_nr != path->slots[0]);
742 del_nr++;
743 }
744
745 if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
746 inode_sub_bytes(inode,
747 extent_end - key.offset);
748 extent_end = ALIGN(extent_end,
749 root->sectorsize);
750 } else if (disk_bytenr > 0) {
751 ret = btrfs_free_extent(trans, root,
752 disk_bytenr, num_bytes, 0,
753 root->root_key.objectid,
754 key.objectid, key.offset -
755 extent_offset);
756 BUG_ON(ret);
757 inode_sub_bytes(inode,
758 extent_end - key.offset);
759 *hint_byte = disk_bytenr;
760 }
761
762 if (end == extent_end)
763 break;
764
765 if (path->slots[0] + 1 < btrfs_header_nritems(leaf)) {
766 path->slots[0]++;
767 goto next_slot;
768 }
769
770 ret = btrfs_del_items(trans, root, path, del_slot,
771 del_nr);
772 BUG_ON(ret);
773
774 del_nr = 0;
775 del_slot = 0;
776
David Sterbab3b4aa72011-04-21 01:20:15 +0200777 btrfs_release_path(path);
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000778 continue;
779 }
780
781 BUG_ON(1);
Chris Mason39279cc2007-06-12 06:35:45 -0400782 }
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000783
784 if (del_nr > 0) {
785 ret = btrfs_del_items(trans, root, path, del_slot, del_nr);
786 BUG_ON(ret);
787 }
788
Chris Mason39279cc2007-06-12 06:35:45 -0400789 btrfs_free_path(path);
790 return ret;
791}
792
Yan Zhengd899e052008-10-30 14:25:28 -0400793static int extent_mergeable(struct extent_buffer *leaf, int slot,
Yan, Zheng6c7d54a2010-01-15 08:43:09 +0000794 u64 objectid, u64 bytenr, u64 orig_offset,
795 u64 *start, u64 *end)
Yan Zhengd899e052008-10-30 14:25:28 -0400796{
797 struct btrfs_file_extent_item *fi;
798 struct btrfs_key key;
799 u64 extent_end;
800
801 if (slot < 0 || slot >= btrfs_header_nritems(leaf))
802 return 0;
803
804 btrfs_item_key_to_cpu(leaf, &key, slot);
805 if (key.objectid != objectid || key.type != BTRFS_EXTENT_DATA_KEY)
806 return 0;
807
808 fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
809 if (btrfs_file_extent_type(leaf, fi) != BTRFS_FILE_EXTENT_REG ||
810 btrfs_file_extent_disk_bytenr(leaf, fi) != bytenr ||
Yan, Zheng6c7d54a2010-01-15 08:43:09 +0000811 btrfs_file_extent_offset(leaf, fi) != key.offset - orig_offset ||
Yan Zhengd899e052008-10-30 14:25:28 -0400812 btrfs_file_extent_compression(leaf, fi) ||
813 btrfs_file_extent_encryption(leaf, fi) ||
814 btrfs_file_extent_other_encoding(leaf, fi))
815 return 0;
816
817 extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi);
818 if ((*start && *start != key.offset) || (*end && *end != extent_end))
819 return 0;
820
821 *start = key.offset;
822 *end = extent_end;
823 return 1;
824}
825
826/*
827 * Mark extent in the range start - end as written.
828 *
829 * This changes extent type from 'pre-allocated' to 'regular'. If only
830 * part of extent is marked as written, the extent will be split into
831 * two or three.
832 */
833int btrfs_mark_extent_written(struct btrfs_trans_handle *trans,
Yan Zhengd899e052008-10-30 14:25:28 -0400834 struct inode *inode, u64 start, u64 end)
835{
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000836 struct btrfs_root *root = BTRFS_I(inode)->root;
Yan Zhengd899e052008-10-30 14:25:28 -0400837 struct extent_buffer *leaf;
838 struct btrfs_path *path;
839 struct btrfs_file_extent_item *fi;
840 struct btrfs_key key;
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000841 struct btrfs_key new_key;
Yan Zhengd899e052008-10-30 14:25:28 -0400842 u64 bytenr;
843 u64 num_bytes;
844 u64 extent_end;
Yan Zheng5d4f98a2009-06-10 10:45:14 -0400845 u64 orig_offset;
Yan Zhengd899e052008-10-30 14:25:28 -0400846 u64 other_start;
847 u64 other_end;
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000848 u64 split;
849 int del_nr = 0;
850 int del_slot = 0;
Yan, Zheng6c7d54a2010-01-15 08:43:09 +0000851 int recow;
Yan Zhengd899e052008-10-30 14:25:28 -0400852 int ret;
Li Zefan33345d012011-04-20 10:31:50 +0800853 u64 ino = btrfs_ino(inode);
Yan Zhengd899e052008-10-30 14:25:28 -0400854
855 btrfs_drop_extent_cache(inode, start, end - 1, 0);
856
857 path = btrfs_alloc_path();
858 BUG_ON(!path);
859again:
Yan, Zheng6c7d54a2010-01-15 08:43:09 +0000860 recow = 0;
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000861 split = start;
Li Zefan33345d012011-04-20 10:31:50 +0800862 key.objectid = ino;
Yan Zhengd899e052008-10-30 14:25:28 -0400863 key.type = BTRFS_EXTENT_DATA_KEY;
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000864 key.offset = split;
Yan Zhengd899e052008-10-30 14:25:28 -0400865
866 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
Josef Bacik41415732011-03-16 13:59:32 -0400867 if (ret < 0)
868 goto out;
Yan Zhengd899e052008-10-30 14:25:28 -0400869 if (ret > 0 && path->slots[0] > 0)
870 path->slots[0]--;
871
872 leaf = path->nodes[0];
873 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
Li Zefan33345d012011-04-20 10:31:50 +0800874 BUG_ON(key.objectid != ino || key.type != BTRFS_EXTENT_DATA_KEY);
Yan Zhengd899e052008-10-30 14:25:28 -0400875 fi = btrfs_item_ptr(leaf, path->slots[0],
876 struct btrfs_file_extent_item);
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000877 BUG_ON(btrfs_file_extent_type(leaf, fi) !=
878 BTRFS_FILE_EXTENT_PREALLOC);
Yan Zhengd899e052008-10-30 14:25:28 -0400879 extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi);
880 BUG_ON(key.offset > start || extent_end < end);
881
882 bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
883 num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi);
Yan Zheng5d4f98a2009-06-10 10:45:14 -0400884 orig_offset = key.offset - btrfs_file_extent_offset(leaf, fi);
Yan, Zheng6c7d54a2010-01-15 08:43:09 +0000885 memcpy(&new_key, &key, sizeof(new_key));
886
887 if (start == key.offset && end < extent_end) {
888 other_start = 0;
889 other_end = start;
890 if (extent_mergeable(leaf, path->slots[0] - 1,
Li Zefan33345d012011-04-20 10:31:50 +0800891 ino, bytenr, orig_offset,
Yan, Zheng6c7d54a2010-01-15 08:43:09 +0000892 &other_start, &other_end)) {
893 new_key.offset = end;
894 btrfs_set_item_key_safe(trans, root, path, &new_key);
895 fi = btrfs_item_ptr(leaf, path->slots[0],
896 struct btrfs_file_extent_item);
897 btrfs_set_file_extent_num_bytes(leaf, fi,
898 extent_end - end);
899 btrfs_set_file_extent_offset(leaf, fi,
900 end - orig_offset);
901 fi = btrfs_item_ptr(leaf, path->slots[0] - 1,
902 struct btrfs_file_extent_item);
903 btrfs_set_file_extent_num_bytes(leaf, fi,
904 end - other_start);
905 btrfs_mark_buffer_dirty(leaf);
906 goto out;
907 }
908 }
909
910 if (start > key.offset && end == extent_end) {
911 other_start = end;
912 other_end = 0;
913 if (extent_mergeable(leaf, path->slots[0] + 1,
Li Zefan33345d012011-04-20 10:31:50 +0800914 ino, bytenr, orig_offset,
Yan, Zheng6c7d54a2010-01-15 08:43:09 +0000915 &other_start, &other_end)) {
916 fi = btrfs_item_ptr(leaf, path->slots[0],
917 struct btrfs_file_extent_item);
918 btrfs_set_file_extent_num_bytes(leaf, fi,
919 start - key.offset);
920 path->slots[0]++;
921 new_key.offset = start;
922 btrfs_set_item_key_safe(trans, root, path, &new_key);
923
924 fi = btrfs_item_ptr(leaf, path->slots[0],
925 struct btrfs_file_extent_item);
926 btrfs_set_file_extent_num_bytes(leaf, fi,
927 other_end - start);
928 btrfs_set_file_extent_offset(leaf, fi,
929 start - orig_offset);
930 btrfs_mark_buffer_dirty(leaf);
931 goto out;
932 }
933 }
Yan Zhengd899e052008-10-30 14:25:28 -0400934
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000935 while (start > key.offset || end < extent_end) {
936 if (key.offset == start)
937 split = end;
Yan Zhengd899e052008-10-30 14:25:28 -0400938
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000939 new_key.offset = split;
940 ret = btrfs_duplicate_item(trans, root, path, &new_key);
941 if (ret == -EAGAIN) {
David Sterbab3b4aa72011-04-21 01:20:15 +0200942 btrfs_release_path(path);
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000943 goto again;
Yan Zhengd899e052008-10-30 14:25:28 -0400944 }
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000945 BUG_ON(ret < 0);
Yan Zhengd899e052008-10-30 14:25:28 -0400946
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000947 leaf = path->nodes[0];
948 fi = btrfs_item_ptr(leaf, path->slots[0] - 1,
Yan Zhengd899e052008-10-30 14:25:28 -0400949 struct btrfs_file_extent_item);
Yan Zhengd899e052008-10-30 14:25:28 -0400950 btrfs_set_file_extent_num_bytes(leaf, fi,
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000951 split - key.offset);
952
953 fi = btrfs_item_ptr(leaf, path->slots[0],
954 struct btrfs_file_extent_item);
955
956 btrfs_set_file_extent_offset(leaf, fi, split - orig_offset);
957 btrfs_set_file_extent_num_bytes(leaf, fi,
958 extent_end - split);
Yan Zhengd899e052008-10-30 14:25:28 -0400959 btrfs_mark_buffer_dirty(leaf);
960
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000961 ret = btrfs_inc_extent_ref(trans, root, bytenr, num_bytes, 0,
962 root->root_key.objectid,
Li Zefan33345d012011-04-20 10:31:50 +0800963 ino, orig_offset);
Yan Zhengd899e052008-10-30 14:25:28 -0400964 BUG_ON(ret);
Yan Zhengd899e052008-10-30 14:25:28 -0400965
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000966 if (split == start) {
967 key.offset = start;
968 } else {
969 BUG_ON(start != key.offset);
Yan Zhengd899e052008-10-30 14:25:28 -0400970 path->slots[0]--;
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000971 extent_end = end;
Yan Zhengd899e052008-10-30 14:25:28 -0400972 }
Yan, Zheng6c7d54a2010-01-15 08:43:09 +0000973 recow = 1;
Yan Zhengd899e052008-10-30 14:25:28 -0400974 }
975
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000976 other_start = end;
977 other_end = 0;
Yan, Zheng6c7d54a2010-01-15 08:43:09 +0000978 if (extent_mergeable(leaf, path->slots[0] + 1,
Li Zefan33345d012011-04-20 10:31:50 +0800979 ino, bytenr, orig_offset,
Yan, Zheng6c7d54a2010-01-15 08:43:09 +0000980 &other_start, &other_end)) {
981 if (recow) {
David Sterbab3b4aa72011-04-21 01:20:15 +0200982 btrfs_release_path(path);
Yan, Zheng6c7d54a2010-01-15 08:43:09 +0000983 goto again;
984 }
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000985 extent_end = other_end;
986 del_slot = path->slots[0] + 1;
987 del_nr++;
988 ret = btrfs_free_extent(trans, root, bytenr, num_bytes,
989 0, root->root_key.objectid,
Li Zefan33345d012011-04-20 10:31:50 +0800990 ino, orig_offset);
Yan, Zheng920bbbf2009-11-12 09:34:08 +0000991 BUG_ON(ret);
992 }
993 other_start = 0;
994 other_end = start;
Yan, Zheng6c7d54a2010-01-15 08:43:09 +0000995 if (extent_mergeable(leaf, path->slots[0] - 1,
Li Zefan33345d012011-04-20 10:31:50 +0800996 ino, bytenr, orig_offset,
Yan, Zheng6c7d54a2010-01-15 08:43:09 +0000997 &other_start, &other_end)) {
998 if (recow) {
David Sterbab3b4aa72011-04-21 01:20:15 +0200999 btrfs_release_path(path);
Yan, Zheng6c7d54a2010-01-15 08:43:09 +00001000 goto again;
1001 }
Yan, Zheng920bbbf2009-11-12 09:34:08 +00001002 key.offset = other_start;
1003 del_slot = path->slots[0];
1004 del_nr++;
1005 ret = btrfs_free_extent(trans, root, bytenr, num_bytes,
1006 0, root->root_key.objectid,
Li Zefan33345d012011-04-20 10:31:50 +08001007 ino, orig_offset);
Yan, Zheng920bbbf2009-11-12 09:34:08 +00001008 BUG_ON(ret);
1009 }
1010 if (del_nr == 0) {
Shaohua Li3f6fae92010-02-11 07:43:00 +00001011 fi = btrfs_item_ptr(leaf, path->slots[0],
1012 struct btrfs_file_extent_item);
Yan, Zheng920bbbf2009-11-12 09:34:08 +00001013 btrfs_set_file_extent_type(leaf, fi,
1014 BTRFS_FILE_EXTENT_REG);
1015 btrfs_mark_buffer_dirty(leaf);
Yan, Zheng6c7d54a2010-01-15 08:43:09 +00001016 } else {
Shaohua Li3f6fae92010-02-11 07:43:00 +00001017 fi = btrfs_item_ptr(leaf, del_slot - 1,
1018 struct btrfs_file_extent_item);
Yan, Zheng6c7d54a2010-01-15 08:43:09 +00001019 btrfs_set_file_extent_type(leaf, fi,
1020 BTRFS_FILE_EXTENT_REG);
1021 btrfs_set_file_extent_num_bytes(leaf, fi,
1022 extent_end - key.offset);
1023 btrfs_mark_buffer_dirty(leaf);
1024
1025 ret = btrfs_del_items(trans, root, path, del_slot, del_nr);
1026 BUG_ON(ret);
Yan, Zheng920bbbf2009-11-12 09:34:08 +00001027 }
Yan, Zheng920bbbf2009-11-12 09:34:08 +00001028out:
Yan Zhengd899e052008-10-30 14:25:28 -04001029 btrfs_free_path(path);
1030 return 0;
1031}
1032
Chris Mason39279cc2007-06-12 06:35:45 -04001033/*
Chris Masonb1bf8622011-02-28 09:52:08 -05001034 * on error we return an unlocked page and the error value
1035 * on success we return a locked page and 0
1036 */
1037static int prepare_uptodate_page(struct page *page, u64 pos)
1038{
1039 int ret = 0;
1040
1041 if ((pos & (PAGE_CACHE_SIZE - 1)) && !PageUptodate(page)) {
1042 ret = btrfs_readpage(NULL, page);
1043 if (ret)
1044 return ret;
1045 lock_page(page);
1046 if (!PageUptodate(page)) {
1047 unlock_page(page);
1048 return -EIO;
1049 }
1050 }
1051 return 0;
1052}
1053
1054/*
Chris Masond352ac62008-09-29 15:18:18 -04001055 * this gets pages into the page cache and locks them down, it also properly
1056 * waits for data=ordered extents to finish before allowing the pages to be
1057 * modified.
Chris Mason39279cc2007-06-12 06:35:45 -04001058 */
Chris Masond3977122009-01-05 21:25:51 -05001059static noinline int prepare_pages(struct btrfs_root *root, struct file *file,
Chris Mason98ed5172008-01-03 10:01:48 -05001060 struct page **pages, size_t num_pages,
1061 loff_t pos, unsigned long first_index,
1062 unsigned long last_index, size_t write_bytes)
Chris Mason39279cc2007-06-12 06:35:45 -04001063{
Josef Bacik2ac55d42010-02-03 19:33:23 +00001064 struct extent_state *cached_state = NULL;
Chris Mason39279cc2007-06-12 06:35:45 -04001065 int i;
1066 unsigned long index = pos >> PAGE_CACHE_SHIFT;
Chris Mason6da6aba2007-12-18 16:15:09 -05001067 struct inode *inode = fdentry(file)->d_inode;
Chris Mason39279cc2007-06-12 06:35:45 -04001068 int err = 0;
Chris Masonb1bf8622011-02-28 09:52:08 -05001069 int faili = 0;
Chris Mason8c2383c2007-06-18 09:57:58 -04001070 u64 start_pos;
Chris Masone6dcd2d2008-07-17 12:53:50 -04001071 u64 last_pos;
Chris Mason8c2383c2007-06-18 09:57:58 -04001072
Chris Mason5f39d392007-10-15 16:14:19 -04001073 start_pos = pos & ~((u64)root->sectorsize - 1);
Chris Masone6dcd2d2008-07-17 12:53:50 -04001074 last_pos = ((u64)index + num_pages) << PAGE_CACHE_SHIFT;
Chris Mason39279cc2007-06-12 06:35:45 -04001075
Yan Zheng9036c102008-10-30 14:19:41 -04001076 if (start_pos > inode->i_size) {
Josef Bacika41ad392011-01-31 15:30:16 -05001077 err = btrfs_cont_expand(inode, i_size_read(inode), start_pos);
Yan Zheng9036c102008-10-30 14:19:41 -04001078 if (err)
1079 return err;
1080 }
1081
Chris Masone6dcd2d2008-07-17 12:53:50 -04001082again:
Chris Mason39279cc2007-06-12 06:35:45 -04001083 for (i = 0; i < num_pages; i++) {
1084 pages[i] = grab_cache_page(inode->i_mapping, index + i);
1085 if (!pages[i]) {
Chris Masonb1bf8622011-02-28 09:52:08 -05001086 faili = i - 1;
1087 err = -ENOMEM;
1088 goto fail;
1089 }
1090
1091 if (i == 0)
1092 err = prepare_uptodate_page(pages[i], pos);
1093 if (i == num_pages - 1)
1094 err = prepare_uptodate_page(pages[i],
1095 pos + write_bytes);
1096 if (err) {
1097 page_cache_release(pages[i]);
1098 faili = i - 1;
1099 goto fail;
Chris Mason39279cc2007-06-12 06:35:45 -04001100 }
Chris Masonccd467d2007-06-28 15:57:36 -04001101 wait_on_page_writeback(pages[i]);
Chris Mason39279cc2007-06-12 06:35:45 -04001102 }
Chris Masonb1bf8622011-02-28 09:52:08 -05001103 err = 0;
Chris Mason07627042008-02-19 11:29:24 -05001104 if (start_pos < inode->i_size) {
Chris Masone6dcd2d2008-07-17 12:53:50 -04001105 struct btrfs_ordered_extent *ordered;
Josef Bacik2ac55d42010-02-03 19:33:23 +00001106 lock_extent_bits(&BTRFS_I(inode)->io_tree,
1107 start_pos, last_pos - 1, 0, &cached_state,
1108 GFP_NOFS);
Chris Masond3977122009-01-05 21:25:51 -05001109 ordered = btrfs_lookup_first_ordered_extent(inode,
1110 last_pos - 1);
Chris Masone6dcd2d2008-07-17 12:53:50 -04001111 if (ordered &&
1112 ordered->file_offset + ordered->len > start_pos &&
1113 ordered->file_offset < last_pos) {
1114 btrfs_put_ordered_extent(ordered);
Josef Bacik2ac55d42010-02-03 19:33:23 +00001115 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1116 start_pos, last_pos - 1,
1117 &cached_state, GFP_NOFS);
Chris Masone6dcd2d2008-07-17 12:53:50 -04001118 for (i = 0; i < num_pages; i++) {
1119 unlock_page(pages[i]);
1120 page_cache_release(pages[i]);
1121 }
1122 btrfs_wait_ordered_range(inode, start_pos,
1123 last_pos - start_pos);
1124 goto again;
1125 }
1126 if (ordered)
1127 btrfs_put_ordered_extent(ordered);
1128
Josef Bacik2ac55d42010-02-03 19:33:23 +00001129 clear_extent_bit(&BTRFS_I(inode)->io_tree, start_pos,
Josef Bacik32c00af2009-10-08 13:34:05 -04001130 last_pos - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
Josef Bacik2ac55d42010-02-03 19:33:23 +00001131 EXTENT_DO_ACCOUNTING, 0, 0, &cached_state,
Chris Mason07627042008-02-19 11:29:24 -05001132 GFP_NOFS);
Josef Bacik2ac55d42010-02-03 19:33:23 +00001133 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1134 start_pos, last_pos - 1, &cached_state,
1135 GFP_NOFS);
Chris Mason07627042008-02-19 11:29:24 -05001136 }
Chris Masone6dcd2d2008-07-17 12:53:50 -04001137 for (i = 0; i < num_pages; i++) {
Chris Masonf87f0572008-08-01 11:27:23 -04001138 clear_page_dirty_for_io(pages[i]);
Chris Masone6dcd2d2008-07-17 12:53:50 -04001139 set_page_extent_mapped(pages[i]);
1140 WARN_ON(!PageLocked(pages[i]));
1141 }
Chris Mason39279cc2007-06-12 06:35:45 -04001142 return 0;
Chris Masonb1bf8622011-02-28 09:52:08 -05001143fail:
1144 while (faili >= 0) {
1145 unlock_page(pages[faili]);
1146 page_cache_release(pages[faili]);
1147 faili--;
1148 }
1149 return err;
1150
Chris Mason39279cc2007-06-12 06:35:45 -04001151}
1152
Josef Bacikd0215f32011-01-25 14:57:24 -05001153static noinline ssize_t __btrfs_buffered_write(struct file *file,
1154 struct iov_iter *i,
1155 loff_t pos)
Josef Bacik4b46fce2010-05-23 11:00:55 -04001156{
Josef Bacik11c65dc2010-05-23 11:07:21 -04001157 struct inode *inode = fdentry(file)->d_inode;
1158 struct btrfs_root *root = BTRFS_I(inode)->root;
Josef Bacik11c65dc2010-05-23 11:07:21 -04001159 struct page **pages = NULL;
Chris Mason39279cc2007-06-12 06:35:45 -04001160 unsigned long first_index;
1161 unsigned long last_index;
Josef Bacikd0215f32011-01-25 14:57:24 -05001162 size_t num_written = 0;
1163 int nrptrs;
Tsutomu Itohc9149232011-03-30 00:57:23 +00001164 int ret = 0;
Chris Masoncb843a62008-10-03 12:30:02 -04001165
Josef Bacikd0215f32011-01-25 14:57:24 -05001166 nrptrs = min((iov_iter_count(i) + PAGE_CACHE_SIZE - 1) /
Josef Bacik11c65dc2010-05-23 11:07:21 -04001167 PAGE_CACHE_SIZE, PAGE_CACHE_SIZE /
1168 (sizeof(struct page *)));
Chris Mason8c2383c2007-06-18 09:57:58 -04001169 pages = kmalloc(nrptrs * sizeof(struct page *), GFP_KERNEL);
Josef Bacikd0215f32011-01-25 14:57:24 -05001170 if (!pages)
1171 return -ENOMEM;
Chris Masonab93dbe2009-10-01 12:29:10 -04001172
Chris Mason39279cc2007-06-12 06:35:45 -04001173 first_index = pos >> PAGE_CACHE_SHIFT;
Josef Bacikd0215f32011-01-25 14:57:24 -05001174 last_index = (pos + iov_iter_count(i)) >> PAGE_CACHE_SHIFT;
Chris Mason39279cc2007-06-12 06:35:45 -04001175
Josef Bacikd0215f32011-01-25 14:57:24 -05001176 while (iov_iter_count(i) > 0) {
Chris Mason39279cc2007-06-12 06:35:45 -04001177 size_t offset = pos & (PAGE_CACHE_SIZE - 1);
Josef Bacikd0215f32011-01-25 14:57:24 -05001178 size_t write_bytes = min(iov_iter_count(i),
Josef Bacik11c65dc2010-05-23 11:07:21 -04001179 nrptrs * (size_t)PAGE_CACHE_SIZE -
Chris Mason8c2383c2007-06-18 09:57:58 -04001180 offset);
Yan, Zheng3a909832011-01-18 13:34:40 +08001181 size_t num_pages = (write_bytes + offset +
1182 PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
Josef Bacikd0215f32011-01-25 14:57:24 -05001183 size_t dirty_pages;
1184 size_t copied;
Chris Mason39279cc2007-06-12 06:35:45 -04001185
Chris Mason8c2383c2007-06-18 09:57:58 -04001186 WARN_ON(num_pages > nrptrs);
Chris Mason1832a6d2007-12-21 16:27:21 -05001187
Xin Zhong914ee292010-12-09 09:30:14 +00001188 /*
1189 * Fault pages before locking them in prepare_pages
1190 * to avoid recursive lock
1191 */
Josef Bacikd0215f32011-01-25 14:57:24 -05001192 if (unlikely(iov_iter_fault_in_readable(i, write_bytes))) {
Xin Zhong914ee292010-12-09 09:30:14 +00001193 ret = -EFAULT;
Josef Bacikd0215f32011-01-25 14:57:24 -05001194 break;
Xin Zhong914ee292010-12-09 09:30:14 +00001195 }
1196
1197 ret = btrfs_delalloc_reserve_space(inode,
1198 num_pages << PAGE_CACHE_SHIFT);
Chris Mason1832a6d2007-12-21 16:27:21 -05001199 if (ret)
Josef Bacikd0215f32011-01-25 14:57:24 -05001200 break;
Chris Mason1832a6d2007-12-21 16:27:21 -05001201
Josef Bacik4a640012011-01-25 15:10:08 -05001202 /*
1203 * This is going to setup the pages array with the number of
1204 * pages we want, so we don't really need to worry about the
1205 * contents of pages from loop to loop
1206 */
Chris Mason39279cc2007-06-12 06:35:45 -04001207 ret = prepare_pages(root, file, pages, num_pages,
1208 pos, first_index, last_index,
Chris Mason8c2383c2007-06-18 09:57:58 -04001209 write_bytes);
Josef Bacik6a632092009-02-20 11:00:09 -05001210 if (ret) {
Xin Zhong914ee292010-12-09 09:30:14 +00001211 btrfs_delalloc_release_space(inode,
1212 num_pages << PAGE_CACHE_SHIFT);
Josef Bacikd0215f32011-01-25 14:57:24 -05001213 break;
Josef Bacik6a632092009-02-20 11:00:09 -05001214 }
Chris Mason39279cc2007-06-12 06:35:45 -04001215
Xin Zhong914ee292010-12-09 09:30:14 +00001216 copied = btrfs_copy_from_user(pos, num_pages,
Josef Bacikd0215f32011-01-25 14:57:24 -05001217 write_bytes, pages, i);
Chris Masonb1bf8622011-02-28 09:52:08 -05001218
1219 /*
1220 * if we have trouble faulting in the pages, fall
1221 * back to one page at a time
1222 */
1223 if (copied < write_bytes)
1224 nrptrs = 1;
1225
1226 if (copied == 0)
1227 dirty_pages = 0;
1228 else
1229 dirty_pages = (copied + offset +
1230 PAGE_CACHE_SIZE - 1) >>
1231 PAGE_CACHE_SHIFT;
Xin Zhong914ee292010-12-09 09:30:14 +00001232
Josef Bacikd0215f32011-01-25 14:57:24 -05001233 /*
1234 * If we had a short copy we need to release the excess delaloc
1235 * bytes we reserved. We need to increment outstanding_extents
1236 * because btrfs_delalloc_release_space will decrement it, but
1237 * we still have an outstanding extent for the chunk we actually
1238 * managed to copy.
1239 */
Xin Zhong914ee292010-12-09 09:30:14 +00001240 if (num_pages > dirty_pages) {
1241 if (copied > 0)
1242 atomic_inc(
1243 &BTRFS_I(inode)->outstanding_extents);
1244 btrfs_delalloc_release_space(inode,
1245 (num_pages - dirty_pages) <<
1246 PAGE_CACHE_SHIFT);
1247 }
1248
1249 if (copied > 0) {
Josef Bacikbe1a12a2011-04-06 13:05:22 -04001250 ret = btrfs_dirty_pages(root, inode, pages,
1251 dirty_pages, pos, copied,
1252 NULL);
Josef Bacikd0215f32011-01-25 14:57:24 -05001253 if (ret) {
1254 btrfs_delalloc_release_space(inode,
1255 dirty_pages << PAGE_CACHE_SHIFT);
1256 btrfs_drop_pages(pages, num_pages);
1257 break;
1258 }
Chris Mason54aa1f42007-06-22 14:16:25 -04001259 }
Chris Mason39279cc2007-06-12 06:35:45 -04001260
Chris Mason39279cc2007-06-12 06:35:45 -04001261 btrfs_drop_pages(pages, num_pages);
Xin Zhong914ee292010-12-09 09:30:14 +00001262
Josef Bacikd0215f32011-01-25 14:57:24 -05001263 cond_resched();
1264
1265 balance_dirty_pages_ratelimited_nr(inode->i_mapping,
1266 dirty_pages);
1267 if (dirty_pages < (root->leafsize >> PAGE_CACHE_SHIFT) + 1)
1268 btrfs_btree_balance_dirty(root, 1);
1269 btrfs_throttle(root);
Chris Mason39279cc2007-06-12 06:35:45 -04001270
Xin Zhong914ee292010-12-09 09:30:14 +00001271 pos += copied;
1272 num_written += copied;
Chris Mason39279cc2007-06-12 06:35:45 -04001273 }
Chris Mason5b92ee72008-01-03 13:46:11 -05001274
Chris Mason8c2383c2007-06-18 09:57:58 -04001275 kfree(pages);
Josef Bacikd0215f32011-01-25 14:57:24 -05001276
1277 return num_written ? num_written : ret;
1278}
1279
1280static ssize_t __btrfs_direct_write(struct kiocb *iocb,
1281 const struct iovec *iov,
1282 unsigned long nr_segs, loff_t pos,
1283 loff_t *ppos, size_t count, size_t ocount)
1284{
1285 struct file *file = iocb->ki_filp;
1286 struct inode *inode = fdentry(file)->d_inode;
1287 struct iov_iter i;
1288 ssize_t written;
1289 ssize_t written_buffered;
1290 loff_t endbyte;
1291 int err;
1292
1293 written = generic_file_direct_write(iocb, iov, &nr_segs, pos, ppos,
1294 count, ocount);
1295
1296 /*
1297 * the generic O_DIRECT will update in-memory i_size after the
1298 * DIOs are done. But our endio handlers that update the on
1299 * disk i_size never update past the in memory i_size. So we
1300 * need one more update here to catch any additions to the
1301 * file
1302 */
1303 if (inode->i_size != BTRFS_I(inode)->disk_i_size) {
1304 btrfs_ordered_update_i_size(inode, inode->i_size, NULL);
1305 mark_inode_dirty(inode);
1306 }
1307
1308 if (written < 0 || written == count)
1309 return written;
1310
1311 pos += written;
1312 count -= written;
1313 iov_iter_init(&i, iov, nr_segs, count, written);
1314 written_buffered = __btrfs_buffered_write(file, &i, pos);
1315 if (written_buffered < 0) {
1316 err = written_buffered;
1317 goto out;
1318 }
1319 endbyte = pos + written_buffered - 1;
1320 err = filemap_write_and_wait_range(file->f_mapping, pos, endbyte);
1321 if (err)
1322 goto out;
1323 written += written_buffered;
1324 *ppos = pos + written_buffered;
1325 invalidate_mapping_pages(file->f_mapping, pos >> PAGE_CACHE_SHIFT,
1326 endbyte >> PAGE_CACHE_SHIFT);
1327out:
1328 return written ? written : err;
1329}
1330
1331static ssize_t btrfs_file_aio_write(struct kiocb *iocb,
1332 const struct iovec *iov,
1333 unsigned long nr_segs, loff_t pos)
1334{
1335 struct file *file = iocb->ki_filp;
1336 struct inode *inode = fdentry(file)->d_inode;
1337 struct btrfs_root *root = BTRFS_I(inode)->root;
1338 loff_t *ppos = &iocb->ki_pos;
1339 ssize_t num_written = 0;
1340 ssize_t err = 0;
1341 size_t count, ocount;
1342
1343 vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
1344
1345 mutex_lock(&inode->i_mutex);
1346
1347 err = generic_segment_checks(iov, &nr_segs, &ocount, VERIFY_READ);
1348 if (err) {
1349 mutex_unlock(&inode->i_mutex);
1350 goto out;
1351 }
1352 count = ocount;
1353
1354 current->backing_dev_info = inode->i_mapping->backing_dev_info;
1355 err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
1356 if (err) {
1357 mutex_unlock(&inode->i_mutex);
1358 goto out;
1359 }
1360
1361 if (count == 0) {
1362 mutex_unlock(&inode->i_mutex);
1363 goto out;
1364 }
1365
1366 err = file_remove_suid(file);
1367 if (err) {
1368 mutex_unlock(&inode->i_mutex);
1369 goto out;
1370 }
1371
1372 /*
1373 * If BTRFS flips readonly due to some impossible error
1374 * (fs_info->fs_state now has BTRFS_SUPER_FLAG_ERROR),
1375 * although we have opened a file as writable, we have
1376 * to stop this write operation to ensure FS consistency.
1377 */
1378 if (root->fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR) {
1379 mutex_unlock(&inode->i_mutex);
1380 err = -EROFS;
1381 goto out;
1382 }
1383
1384 file_update_time(file);
1385 BTRFS_I(inode)->sequence++;
1386
1387 if (unlikely(file->f_flags & O_DIRECT)) {
1388 num_written = __btrfs_direct_write(iocb, iov, nr_segs,
1389 pos, ppos, count, ocount);
1390 } else {
1391 struct iov_iter i;
1392
1393 iov_iter_init(&i, iov, nr_segs, count, num_written);
1394
1395 num_written = __btrfs_buffered_write(file, &i, pos);
1396 if (num_written > 0)
1397 *ppos = pos + num_written;
1398 }
1399
1400 mutex_unlock(&inode->i_mutex);
Chris Mason2ff3e9b2007-10-29 14:36:41 -04001401
Chris Mason5a3f23d2009-03-31 13:27:11 -04001402 /*
1403 * we want to make sure fsync finds this change
1404 * but we haven't joined a transaction running right now.
1405 *
1406 * Later on, someone is sure to update the inode and get the
1407 * real transid recorded.
1408 *
1409 * We set last_trans now to the fs_info generation + 1,
1410 * this will either be one more than the running transaction
1411 * or the generation used for the next transaction if there isn't
1412 * one running right now.
1413 */
1414 BTRFS_I(inode)->last_trans = root->fs_info->generation + 1;
Josef Bacikd0215f32011-01-25 14:57:24 -05001415 if (num_written > 0 || num_written == -EIOCBQUEUED) {
1416 err = generic_write_sync(file, pos, num_written);
1417 if (err < 0 && num_written > 0)
Chris Mason2ff3e9b2007-10-29 14:36:41 -04001418 num_written = err;
1419 }
Josef Bacikd0215f32011-01-25 14:57:24 -05001420out:
Chris Mason39279cc2007-06-12 06:35:45 -04001421 current->backing_dev_info = NULL;
Chris Mason39279cc2007-06-12 06:35:45 -04001422 return num_written ? num_written : err;
1423}
1424
Chris Masond3977122009-01-05 21:25:51 -05001425int btrfs_release_file(struct inode *inode, struct file *filp)
Mingminge1b81e62008-05-27 10:55:43 -04001426{
Chris Mason5a3f23d2009-03-31 13:27:11 -04001427 /*
1428 * ordered_data_close is set by settattr when we are about to truncate
1429 * a file from a non-zero size to a zero size. This tries to
1430 * flush down new bytes that may have been written if the
1431 * application were using truncate to replace a file in place.
1432 */
1433 if (BTRFS_I(inode)->ordered_data_close) {
1434 BTRFS_I(inode)->ordered_data_close = 0;
1435 btrfs_add_ordered_operation(NULL, BTRFS_I(inode)->root, inode);
1436 if (inode->i_size > BTRFS_ORDERED_OPERATIONS_FLUSH_LIMIT)
1437 filemap_flush(inode->i_mapping);
1438 }
Sage Weil6bf13c02008-06-10 10:07:39 -04001439 if (filp->private_data)
1440 btrfs_ioctl_trans_end(filp);
Mingminge1b81e62008-05-27 10:55:43 -04001441 return 0;
1442}
1443
Chris Masond352ac62008-09-29 15:18:18 -04001444/*
1445 * fsync call for both files and directories. This logs the inode into
1446 * the tree log instead of forcing full commits whenever possible.
1447 *
1448 * It needs to call filemap_fdatawait so that all ordered extent updates are
1449 * in the metadata btree are up to date for copying to the log.
1450 *
1451 * It drops the inode mutex before doing the tree log commit. This is an
1452 * important optimization for directories because holding the mutex prevents
1453 * new operations on the dir while we write to disk.
1454 */
Christoph Hellwig7ea80852010-05-26 17:53:25 +02001455int btrfs_sync_file(struct file *file, int datasync)
Chris Mason39279cc2007-06-12 06:35:45 -04001456{
Christoph Hellwig7ea80852010-05-26 17:53:25 +02001457 struct dentry *dentry = file->f_path.dentry;
Chris Mason39279cc2007-06-12 06:35:45 -04001458 struct inode *inode = dentry->d_inode;
1459 struct btrfs_root *root = BTRFS_I(inode)->root;
Josef Bacik15ee9bc2007-08-10 16:22:09 -04001460 int ret = 0;
Chris Mason39279cc2007-06-12 06:35:45 -04001461 struct btrfs_trans_handle *trans;
1462
liubo1abe9b82011-03-24 11:18:59 +00001463 trace_btrfs_sync_file(file, datasync);
Chris Mason257c62e2009-10-13 13:21:08 -04001464
1465 /* we wait first, since the writeback may change the inode */
1466 root->log_batch++;
1467 /* the VFS called filemap_fdatawrite for us */
1468 btrfs_wait_ordered_range(inode, 0, (u64)-1);
1469 root->log_batch++;
1470
Chris Mason39279cc2007-06-12 06:35:45 -04001471 /*
Josef Bacik15ee9bc2007-08-10 16:22:09 -04001472 * check the transaction that last modified this inode
1473 * and see if its already been committed
Chris Mason39279cc2007-06-12 06:35:45 -04001474 */
Josef Bacik15ee9bc2007-08-10 16:22:09 -04001475 if (!BTRFS_I(inode)->last_trans)
1476 goto out;
Chris Masona2135012008-06-25 16:01:30 -04001477
Chris Mason257c62e2009-10-13 13:21:08 -04001478 /*
1479 * if the last transaction that changed this file was before
1480 * the current transaction, we can bail out now without any
1481 * syncing
1482 */
Josef Bacika4abeea2011-04-11 17:25:13 -04001483 smp_mb();
Josef Bacik15ee9bc2007-08-10 16:22:09 -04001484 if (BTRFS_I(inode)->last_trans <=
1485 root->fs_info->last_trans_committed) {
1486 BTRFS_I(inode)->last_trans = 0;
Josef Bacik15ee9bc2007-08-10 16:22:09 -04001487 goto out;
1488 }
Josef Bacik15ee9bc2007-08-10 16:22:09 -04001489
1490 /*
Chris Masona52d9a82007-08-27 16:49:44 -04001491 * ok we haven't committed the transaction yet, lets do a commit
1492 */
Dan Carpenter6f902af2010-05-29 09:49:07 +00001493 if (file->private_data)
Sage Weil6bf13c02008-06-10 10:07:39 -04001494 btrfs_ioctl_trans_end(file);
1495
Yan, Zhenga22285a2010-05-16 10:48:46 -04001496 trans = btrfs_start_transaction(root, 0);
1497 if (IS_ERR(trans)) {
1498 ret = PTR_ERR(trans);
Chris Mason39279cc2007-06-12 06:35:45 -04001499 goto out;
1500 }
Chris Masone02119d2008-09-05 16:13:11 -04001501
Chris Mason2cfbd502009-02-20 10:55:10 -05001502 ret = btrfs_log_dentry_safe(trans, root, dentry);
Chris Masond3977122009-01-05 21:25:51 -05001503 if (ret < 0)
Chris Masone02119d2008-09-05 16:13:11 -04001504 goto out;
Chris Mason49eb7e42008-09-11 15:53:12 -04001505
1506 /* we've logged all the items and now have a consistent
1507 * version of the file in the log. It is possible that
1508 * someone will come in and modify the file, but that's
1509 * fine because the log is consistent on disk, and we
1510 * have references to all of the file's extents
1511 *
1512 * It is possible that someone will come in and log the
1513 * file again, but that will end up using the synchronization
1514 * inside btrfs_sync_log to keep things safe.
1515 */
Chris Mason2cfbd502009-02-20 10:55:10 -05001516 mutex_unlock(&dentry->d_inode->i_mutex);
Chris Mason49eb7e42008-09-11 15:53:12 -04001517
Chris Mason257c62e2009-10-13 13:21:08 -04001518 if (ret != BTRFS_NO_LOG_SYNC) {
1519 if (ret > 0) {
Chris Mason12fcfd22009-03-24 10:24:20 -04001520 ret = btrfs_commit_transaction(trans, root);
Chris Mason257c62e2009-10-13 13:21:08 -04001521 } else {
1522 ret = btrfs_sync_log(trans, root);
1523 if (ret == 0)
1524 ret = btrfs_end_transaction(trans, root);
1525 else
1526 ret = btrfs_commit_transaction(trans, root);
1527 }
1528 } else {
1529 ret = btrfs_end_transaction(trans, root);
Chris Masone02119d2008-09-05 16:13:11 -04001530 }
Chris Mason2cfbd502009-02-20 10:55:10 -05001531 mutex_lock(&dentry->d_inode->i_mutex);
Chris Mason39279cc2007-06-12 06:35:45 -04001532out:
Roel Kluin014e4ac2010-01-29 10:42:11 +00001533 return ret > 0 ? -EIO : ret;
Chris Mason39279cc2007-06-12 06:35:45 -04001534}
1535
Alexey Dobriyanf0f37e22009-09-27 22:29:37 +04001536static const struct vm_operations_struct btrfs_file_vm_ops = {
Chris Mason92fee662007-07-25 12:31:35 -04001537 .fault = filemap_fault,
Chris Mason9ebefb182007-06-15 13:50:00 -04001538 .page_mkwrite = btrfs_page_mkwrite,
1539};
1540
1541static int btrfs_file_mmap(struct file *filp, struct vm_area_struct *vma)
1542{
Miao Xie058a4572010-05-20 07:21:50 +00001543 struct address_space *mapping = filp->f_mapping;
1544
1545 if (!mapping->a_ops->readpage)
1546 return -ENOEXEC;
1547
Chris Mason9ebefb182007-06-15 13:50:00 -04001548 file_accessed(filp);
Miao Xie058a4572010-05-20 07:21:50 +00001549 vma->vm_ops = &btrfs_file_vm_ops;
1550 vma->vm_flags |= VM_CAN_NONLINEAR;
1551
Chris Mason9ebefb182007-06-15 13:50:00 -04001552 return 0;
1553}
1554
Christoph Hellwig2fe17c12011-01-14 13:07:43 +01001555static long btrfs_fallocate(struct file *file, int mode,
1556 loff_t offset, loff_t len)
1557{
1558 struct inode *inode = file->f_path.dentry->d_inode;
1559 struct extent_state *cached_state = NULL;
1560 u64 cur_offset;
1561 u64 last_byte;
1562 u64 alloc_start;
1563 u64 alloc_end;
1564 u64 alloc_hint = 0;
1565 u64 locked_end;
1566 u64 mask = BTRFS_I(inode)->root->sectorsize - 1;
1567 struct extent_map *em;
1568 int ret;
1569
1570 alloc_start = offset & ~mask;
1571 alloc_end = (offset + len + mask) & ~mask;
1572
1573 /* We only support the FALLOC_FL_KEEP_SIZE mode */
1574 if (mode & ~FALLOC_FL_KEEP_SIZE)
1575 return -EOPNOTSUPP;
1576
1577 /*
1578 * wait for ordered IO before we have any locks. We'll loop again
1579 * below with the locks held.
1580 */
1581 btrfs_wait_ordered_range(inode, alloc_start, alloc_end - alloc_start);
1582
1583 mutex_lock(&inode->i_mutex);
1584 ret = inode_newsize_ok(inode, alloc_end);
1585 if (ret)
1586 goto out;
1587
1588 if (alloc_start > inode->i_size) {
Josef Bacika41ad392011-01-31 15:30:16 -05001589 ret = btrfs_cont_expand(inode, i_size_read(inode),
1590 alloc_start);
Christoph Hellwig2fe17c12011-01-14 13:07:43 +01001591 if (ret)
1592 goto out;
1593 }
1594
1595 ret = btrfs_check_data_free_space(inode, alloc_end - alloc_start);
1596 if (ret)
1597 goto out;
1598
1599 locked_end = alloc_end - 1;
1600 while (1) {
1601 struct btrfs_ordered_extent *ordered;
1602
1603 /* the extent lock is ordered inside the running
1604 * transaction
1605 */
1606 lock_extent_bits(&BTRFS_I(inode)->io_tree, alloc_start,
1607 locked_end, 0, &cached_state, GFP_NOFS);
1608 ordered = btrfs_lookup_first_ordered_extent(inode,
1609 alloc_end - 1);
1610 if (ordered &&
1611 ordered->file_offset + ordered->len > alloc_start &&
1612 ordered->file_offset < alloc_end) {
1613 btrfs_put_ordered_extent(ordered);
1614 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1615 alloc_start, locked_end,
1616 &cached_state, GFP_NOFS);
1617 /*
1618 * we can't wait on the range with the transaction
1619 * running or with the extent lock held
1620 */
1621 btrfs_wait_ordered_range(inode, alloc_start,
1622 alloc_end - alloc_start);
1623 } else {
1624 if (ordered)
1625 btrfs_put_ordered_extent(ordered);
1626 break;
1627 }
1628 }
1629
1630 cur_offset = alloc_start;
1631 while (1) {
1632 em = btrfs_get_extent(inode, NULL, 0, cur_offset,
1633 alloc_end - cur_offset, 0);
David Sterbac7040052011-04-19 18:00:01 +02001634 BUG_ON(IS_ERR_OR_NULL(em));
Christoph Hellwig2fe17c12011-01-14 13:07:43 +01001635 last_byte = min(extent_map_end(em), alloc_end);
1636 last_byte = (last_byte + mask) & ~mask;
1637 if (em->block_start == EXTENT_MAP_HOLE ||
1638 (cur_offset >= inode->i_size &&
1639 !test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) {
1640 ret = btrfs_prealloc_file_range(inode, mode, cur_offset,
1641 last_byte - cur_offset,
1642 1 << inode->i_blkbits,
1643 offset + len,
1644 &alloc_hint);
1645 if (ret < 0) {
1646 free_extent_map(em);
1647 break;
1648 }
1649 }
1650 free_extent_map(em);
1651
1652 cur_offset = last_byte;
1653 if (cur_offset >= alloc_end) {
1654 ret = 0;
1655 break;
1656 }
1657 }
1658 unlock_extent_cached(&BTRFS_I(inode)->io_tree, alloc_start, locked_end,
1659 &cached_state, GFP_NOFS);
1660
1661 btrfs_free_reserved_data_space(inode, alloc_end - alloc_start);
1662out:
1663 mutex_unlock(&inode->i_mutex);
1664 return ret;
1665}
1666
Alexey Dobriyan828c0952009-10-01 15:43:56 -07001667const struct file_operations btrfs_file_operations = {
Chris Mason39279cc2007-06-12 06:35:45 -04001668 .llseek = generic_file_llseek,
1669 .read = do_sync_read,
Miao Xie4a0010712010-06-07 03:38:51 +00001670 .write = do_sync_write,
Chris Mason9ebefb182007-06-15 13:50:00 -04001671 .aio_read = generic_file_aio_read,
Chris Masone9906a92007-12-14 12:56:58 -05001672 .splice_read = generic_file_splice_read,
Josef Bacik11c65dc2010-05-23 11:07:21 -04001673 .aio_write = btrfs_file_aio_write,
Chris Mason9ebefb182007-06-15 13:50:00 -04001674 .mmap = btrfs_file_mmap,
Chris Mason39279cc2007-06-12 06:35:45 -04001675 .open = generic_file_open,
Mingminge1b81e62008-05-27 10:55:43 -04001676 .release = btrfs_release_file,
Chris Mason39279cc2007-06-12 06:35:45 -04001677 .fsync = btrfs_sync_file,
Christoph Hellwig2fe17c12011-01-14 13:07:43 +01001678 .fallocate = btrfs_fallocate,
Christoph Hellwig34287aa2007-09-14 10:22:47 -04001679 .unlocked_ioctl = btrfs_ioctl,
Chris Mason39279cc2007-06-12 06:35:45 -04001680#ifdef CONFIG_COMPAT
Christoph Hellwig34287aa2007-09-14 10:22:47 -04001681 .compat_ioctl = btrfs_ioctl,
Chris Mason39279cc2007-06-12 06:35:45 -04001682#endif
1683};