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6cbd5570 CM |
1 | /* |
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 | ||
39279cc3 CM |
19 | #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> | |
39279cc3 CM |
25 | #include <linux/backing-dev.h> |
26 | #include <linux/mpage.h> | |
27 | #include <linux/swap.h> | |
28 | #include <linux/writeback.h> | |
29 | #include <linux/statfs.h> | |
30 | #include <linux/compat.h> | |
31 | #include "ctree.h" | |
32 | #include "disk-io.h" | |
33 | #include "transaction.h" | |
34 | #include "btrfs_inode.h" | |
35 | #include "ioctl.h" | |
36 | #include "print-tree.h" | |
e02119d5 CM |
37 | #include "tree-log.h" |
38 | #include "locking.h" | |
12fa8ec6 | 39 | #include "compat.h" |
39279cc3 CM |
40 | |
41 | ||
d352ac68 CM |
42 | /* simple helper to fault in pages and copy. This should go away |
43 | * and be replaced with calls into generic code. | |
44 | */ | |
d397712b | 45 | static noinline int btrfs_copy_from_user(loff_t pos, int num_pages, |
a1b32a59 CM |
46 | int write_bytes, |
47 | struct page **prepared_pages, | |
d397712b | 48 | const char __user *buf) |
39279cc3 CM |
49 | { |
50 | long page_fault = 0; | |
51 | int i; | |
52 | int offset = pos & (PAGE_CACHE_SIZE - 1); | |
53 | ||
54 | for (i = 0; i < num_pages && write_bytes > 0; i++, offset = 0) { | |
55 | size_t count = min_t(size_t, | |
56 | PAGE_CACHE_SIZE - offset, write_bytes); | |
57 | struct page *page = prepared_pages[i]; | |
58 | fault_in_pages_readable(buf, count); | |
59 | ||
60 | /* Copy data from userspace to the current page */ | |
61 | kmap(page); | |
62 | page_fault = __copy_from_user(page_address(page) + offset, | |
63 | buf, count); | |
64 | /* Flush processor's dcache for this page */ | |
65 | flush_dcache_page(page); | |
66 | kunmap(page); | |
67 | buf += count; | |
68 | write_bytes -= count; | |
69 | ||
70 | if (page_fault) | |
71 | break; | |
72 | } | |
73 | return page_fault ? -EFAULT : 0; | |
74 | } | |
75 | ||
d352ac68 CM |
76 | /* |
77 | * unlocks pages after btrfs_file_write is done with them | |
78 | */ | |
d397712b | 79 | static noinline void btrfs_drop_pages(struct page **pages, size_t num_pages) |
39279cc3 CM |
80 | { |
81 | size_t i; | |
82 | for (i = 0; i < num_pages; i++) { | |
83 | if (!pages[i]) | |
84 | break; | |
d352ac68 CM |
85 | /* page checked is some magic around finding pages that |
86 | * have been modified without going through btrfs_set_page_dirty | |
87 | * clear it here | |
88 | */ | |
4a096752 | 89 | ClearPageChecked(pages[i]); |
39279cc3 CM |
90 | unlock_page(pages[i]); |
91 | mark_page_accessed(pages[i]); | |
92 | page_cache_release(pages[i]); | |
93 | } | |
94 | } | |
95 | ||
d352ac68 CM |
96 | /* |
97 | * after copy_from_user, pages need to be dirtied and we need to make | |
98 | * sure holes are created between the current EOF and the start of | |
99 | * any next extents (if required). | |
100 | * | |
101 | * this also makes the decision about creating an inline extent vs | |
102 | * doing real data extents, marking pages dirty and delalloc as required. | |
103 | */ | |
d397712b | 104 | static noinline int dirty_and_release_pages(struct btrfs_trans_handle *trans, |
39279cc3 CM |
105 | struct btrfs_root *root, |
106 | struct file *file, | |
107 | struct page **pages, | |
108 | size_t num_pages, | |
109 | loff_t pos, | |
110 | size_t write_bytes) | |
111 | { | |
39279cc3 | 112 | int err = 0; |
a52d9a80 | 113 | int i; |
6da6abae | 114 | struct inode *inode = fdentry(file)->d_inode; |
db94535d | 115 | u64 num_bytes; |
a52d9a80 CM |
116 | u64 start_pos; |
117 | u64 end_of_last_block; | |
118 | u64 end_pos = pos + write_bytes; | |
119 | loff_t isize = i_size_read(inode); | |
39279cc3 | 120 | |
5f39d397 | 121 | start_pos = pos & ~((u64)root->sectorsize - 1); |
db94535d CM |
122 | num_bytes = (write_bytes + pos - start_pos + |
123 | root->sectorsize - 1) & ~((u64)root->sectorsize - 1); | |
39279cc3 | 124 | |
db94535d | 125 | end_of_last_block = start_pos + num_bytes - 1; |
9ed74f2d JB |
126 | err = btrfs_set_extent_delalloc(inode, start_pos, end_of_last_block); |
127 | if (err) | |
128 | return err; | |
129 | ||
c8b97818 CM |
130 | for (i = 0; i < num_pages; i++) { |
131 | struct page *p = pages[i]; | |
132 | SetPageUptodate(p); | |
133 | ClearPageChecked(p); | |
134 | set_page_dirty(p); | |
a52d9a80 CM |
135 | } |
136 | if (end_pos > isize) { | |
137 | i_size_write(inode, end_pos); | |
f597bb19 CM |
138 | /* we've only changed i_size in ram, and we haven't updated |
139 | * the disk i_size. There is no need to log the inode | |
140 | * at this time. | |
141 | */ | |
39279cc3 | 142 | } |
39279cc3 CM |
143 | return err; |
144 | } | |
145 | ||
d352ac68 CM |
146 | /* |
147 | * this drops all the extents in the cache that intersect the range | |
148 | * [start, end]. Existing extents are split as required. | |
149 | */ | |
5b21f2ed ZY |
150 | int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end, |
151 | int skip_pinned) | |
a52d9a80 CM |
152 | { |
153 | struct extent_map *em; | |
3b951516 CM |
154 | struct extent_map *split = NULL; |
155 | struct extent_map *split2 = NULL; | |
a52d9a80 | 156 | struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; |
39b5637f | 157 | u64 len = end - start + 1; |
3b951516 CM |
158 | int ret; |
159 | int testend = 1; | |
5b21f2ed | 160 | unsigned long flags; |
c8b97818 | 161 | int compressed = 0; |
a52d9a80 | 162 | |
e6dcd2dc | 163 | WARN_ON(end < start); |
3b951516 | 164 | if (end == (u64)-1) { |
39b5637f | 165 | len = (u64)-1; |
3b951516 CM |
166 | testend = 0; |
167 | } | |
d397712b | 168 | while (1) { |
3b951516 CM |
169 | if (!split) |
170 | split = alloc_extent_map(GFP_NOFS); | |
171 | if (!split2) | |
172 | split2 = alloc_extent_map(GFP_NOFS); | |
173 | ||
890871be | 174 | write_lock(&em_tree->lock); |
39b5637f | 175 | em = lookup_extent_mapping(em_tree, start, len); |
d1310b2e | 176 | if (!em) { |
890871be | 177 | write_unlock(&em_tree->lock); |
a52d9a80 | 178 | break; |
d1310b2e | 179 | } |
5b21f2ed ZY |
180 | flags = em->flags; |
181 | if (skip_pinned && test_bit(EXTENT_FLAG_PINNED, &em->flags)) { | |
5b21f2ed ZY |
182 | if (em->start <= start && |
183 | (!testend || em->start + em->len >= start + len)) { | |
184 | free_extent_map(em); | |
a1ed835e | 185 | write_unlock(&em_tree->lock); |
5b21f2ed ZY |
186 | break; |
187 | } | |
188 | if (start < em->start) { | |
189 | len = em->start - start; | |
190 | } else { | |
191 | len = start + len - (em->start + em->len); | |
192 | start = em->start + em->len; | |
193 | } | |
194 | free_extent_map(em); | |
a1ed835e | 195 | write_unlock(&em_tree->lock); |
5b21f2ed ZY |
196 | continue; |
197 | } | |
c8b97818 | 198 | compressed = test_bit(EXTENT_FLAG_COMPRESSED, &em->flags); |
3ce7e67a | 199 | clear_bit(EXTENT_FLAG_PINNED, &em->flags); |
a52d9a80 | 200 | remove_extent_mapping(em_tree, em); |
3b951516 CM |
201 | |
202 | if (em->block_start < EXTENT_MAP_LAST_BYTE && | |
203 | em->start < start) { | |
204 | split->start = em->start; | |
205 | split->len = start - em->start; | |
ff5b7ee3 | 206 | split->orig_start = em->orig_start; |
3b951516 | 207 | split->block_start = em->block_start; |
c8b97818 CM |
208 | |
209 | if (compressed) | |
210 | split->block_len = em->block_len; | |
211 | else | |
212 | split->block_len = split->len; | |
213 | ||
3b951516 | 214 | split->bdev = em->bdev; |
5b21f2ed | 215 | split->flags = flags; |
3b951516 CM |
216 | ret = add_extent_mapping(em_tree, split); |
217 | BUG_ON(ret); | |
218 | free_extent_map(split); | |
219 | split = split2; | |
220 | split2 = NULL; | |
221 | } | |
222 | if (em->block_start < EXTENT_MAP_LAST_BYTE && | |
223 | testend && em->start + em->len > start + len) { | |
224 | u64 diff = start + len - em->start; | |
225 | ||
226 | split->start = start + len; | |
227 | split->len = em->start + em->len - (start + len); | |
228 | split->bdev = em->bdev; | |
5b21f2ed | 229 | split->flags = flags; |
3b951516 | 230 | |
c8b97818 CM |
231 | if (compressed) { |
232 | split->block_len = em->block_len; | |
233 | split->block_start = em->block_start; | |
445a6944 | 234 | split->orig_start = em->orig_start; |
c8b97818 CM |
235 | } else { |
236 | split->block_len = split->len; | |
237 | split->block_start = em->block_start + diff; | |
445a6944 | 238 | split->orig_start = split->start; |
c8b97818 | 239 | } |
3b951516 CM |
240 | |
241 | ret = add_extent_mapping(em_tree, split); | |
242 | BUG_ON(ret); | |
243 | free_extent_map(split); | |
244 | split = NULL; | |
245 | } | |
890871be | 246 | write_unlock(&em_tree->lock); |
d1310b2e | 247 | |
a52d9a80 CM |
248 | /* once for us */ |
249 | free_extent_map(em); | |
250 | /* once for the tree*/ | |
251 | free_extent_map(em); | |
252 | } | |
3b951516 CM |
253 | if (split) |
254 | free_extent_map(split); | |
255 | if (split2) | |
256 | free_extent_map(split2); | |
a52d9a80 CM |
257 | return 0; |
258 | } | |
259 | ||
39279cc3 CM |
260 | /* |
261 | * this is very complex, but the basic idea is to drop all extents | |
262 | * in the range start - end. hint_block is filled in with a block number | |
263 | * that would be a good hint to the block allocator for this file. | |
264 | * | |
265 | * If an extent intersects the range but is not entirely inside the range | |
266 | * it is either truncated or split. Anything entirely inside the range | |
267 | * is deleted from the tree. | |
268 | */ | |
920bbbfb YZ |
269 | int btrfs_drop_extents(struct btrfs_trans_handle *trans, struct inode *inode, |
270 | u64 start, u64 end, u64 *hint_byte, int drop_cache) | |
39279cc3 | 271 | { |
920bbbfb | 272 | struct btrfs_root *root = BTRFS_I(inode)->root; |
5f39d397 | 273 | struct extent_buffer *leaf; |
920bbbfb | 274 | struct btrfs_file_extent_item *fi; |
39279cc3 | 275 | struct btrfs_path *path; |
00f5c795 | 276 | struct btrfs_key key; |
920bbbfb YZ |
277 | struct btrfs_key new_key; |
278 | u64 search_start = start; | |
279 | u64 disk_bytenr = 0; | |
280 | u64 num_bytes = 0; | |
281 | u64 extent_offset = 0; | |
282 | u64 extent_end = 0; | |
283 | int del_nr = 0; | |
284 | int del_slot = 0; | |
285 | int extent_type; | |
ccd467d6 | 286 | int recow; |
00f5c795 | 287 | int ret; |
39279cc3 | 288 | |
a1ed835e CM |
289 | if (drop_cache) |
290 | btrfs_drop_extent_cache(inode, start, end - 1, 0); | |
a52d9a80 | 291 | |
39279cc3 CM |
292 | path = btrfs_alloc_path(); |
293 | if (!path) | |
294 | return -ENOMEM; | |
920bbbfb | 295 | |
d397712b | 296 | while (1) { |
ccd467d6 | 297 | recow = 0; |
39279cc3 CM |
298 | ret = btrfs_lookup_file_extent(trans, root, path, inode->i_ino, |
299 | search_start, -1); | |
300 | if (ret < 0) | |
920bbbfb YZ |
301 | break; |
302 | if (ret > 0 && path->slots[0] > 0 && search_start == start) { | |
303 | leaf = path->nodes[0]; | |
304 | btrfs_item_key_to_cpu(leaf, &key, path->slots[0] - 1); | |
305 | if (key.objectid == inode->i_ino && | |
306 | key.type == BTRFS_EXTENT_DATA_KEY) | |
307 | path->slots[0]--; | |
39279cc3 | 308 | } |
920bbbfb | 309 | ret = 0; |
8c2383c3 | 310 | next_slot: |
5f39d397 | 311 | leaf = path->nodes[0]; |
920bbbfb YZ |
312 | if (path->slots[0] >= btrfs_header_nritems(leaf)) { |
313 | BUG_ON(del_nr > 0); | |
314 | ret = btrfs_next_leaf(root, path); | |
315 | if (ret < 0) | |
316 | break; | |
317 | if (ret > 0) { | |
318 | ret = 0; | |
319 | break; | |
8c2383c3 | 320 | } |
920bbbfb YZ |
321 | leaf = path->nodes[0]; |
322 | recow = 1; | |
323 | } | |
324 | ||
325 | btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); | |
326 | if (key.objectid > inode->i_ino || | |
327 | key.type > BTRFS_EXTENT_DATA_KEY || key.offset >= end) | |
328 | break; | |
329 | ||
330 | fi = btrfs_item_ptr(leaf, path->slots[0], | |
331 | struct btrfs_file_extent_item); | |
332 | extent_type = btrfs_file_extent_type(leaf, fi); | |
333 | ||
334 | if (extent_type == BTRFS_FILE_EXTENT_REG || | |
335 | extent_type == BTRFS_FILE_EXTENT_PREALLOC) { | |
336 | disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); | |
337 | num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi); | |
338 | extent_offset = btrfs_file_extent_offset(leaf, fi); | |
339 | extent_end = key.offset + | |
340 | btrfs_file_extent_num_bytes(leaf, fi); | |
341 | } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) { | |
342 | extent_end = key.offset + | |
343 | btrfs_file_extent_inline_len(leaf, fi); | |
8c2383c3 | 344 | } else { |
920bbbfb | 345 | WARN_ON(1); |
8c2383c3 | 346 | extent_end = search_start; |
39279cc3 CM |
347 | } |
348 | ||
920bbbfb YZ |
349 | if (extent_end <= search_start) { |
350 | path->slots[0]++; | |
8c2383c3 | 351 | goto next_slot; |
39279cc3 CM |
352 | } |
353 | ||
920bbbfb YZ |
354 | search_start = max(key.offset, start); |
355 | if (recow) { | |
356 | btrfs_release_path(root, path); | |
357 | continue; | |
39279cc3 | 358 | } |
6643558d | 359 | |
920bbbfb YZ |
360 | /* |
361 | * | - range to drop - | | |
362 | * | -------- extent -------- | | |
363 | */ | |
364 | if (start > key.offset && end < extent_end) { | |
365 | BUG_ON(del_nr > 0); | |
366 | BUG_ON(extent_type == BTRFS_FILE_EXTENT_INLINE); | |
367 | ||
368 | memcpy(&new_key, &key, sizeof(new_key)); | |
369 | new_key.offset = start; | |
370 | ret = btrfs_duplicate_item(trans, root, path, | |
371 | &new_key); | |
372 | if (ret == -EAGAIN) { | |
373 | btrfs_release_path(root, path); | |
374 | continue; | |
6643558d | 375 | } |
920bbbfb YZ |
376 | if (ret < 0) |
377 | break; | |
378 | ||
379 | leaf = path->nodes[0]; | |
380 | fi = btrfs_item_ptr(leaf, path->slots[0] - 1, | |
381 | struct btrfs_file_extent_item); | |
382 | btrfs_set_file_extent_num_bytes(leaf, fi, | |
383 | start - key.offset); | |
384 | ||
385 | fi = btrfs_item_ptr(leaf, path->slots[0], | |
386 | struct btrfs_file_extent_item); | |
387 | ||
388 | extent_offset += start - key.offset; | |
389 | btrfs_set_file_extent_offset(leaf, fi, extent_offset); | |
390 | btrfs_set_file_extent_num_bytes(leaf, fi, | |
391 | extent_end - start); | |
392 | btrfs_mark_buffer_dirty(leaf); | |
393 | ||
394 | if (disk_bytenr > 0) { | |
771ed689 | 395 | ret = btrfs_inc_extent_ref(trans, root, |
920bbbfb YZ |
396 | disk_bytenr, num_bytes, 0, |
397 | root->root_key.objectid, | |
398 | new_key.objectid, | |
399 | start - extent_offset); | |
771ed689 | 400 | BUG_ON(ret); |
920bbbfb | 401 | *hint_byte = disk_bytenr; |
771ed689 | 402 | } |
920bbbfb | 403 | key.offset = start; |
6643558d | 404 | } |
920bbbfb YZ |
405 | /* |
406 | * | ---- range to drop ----- | | |
407 | * | -------- extent -------- | | |
408 | */ | |
409 | if (start <= key.offset && end < extent_end) { | |
410 | BUG_ON(extent_type == BTRFS_FILE_EXTENT_INLINE); | |
6643558d | 411 | |
920bbbfb YZ |
412 | memcpy(&new_key, &key, sizeof(new_key)); |
413 | new_key.offset = end; | |
414 | btrfs_set_item_key_safe(trans, root, path, &new_key); | |
415 | ||
416 | extent_offset += end - key.offset; | |
417 | btrfs_set_file_extent_offset(leaf, fi, extent_offset); | |
418 | btrfs_set_file_extent_num_bytes(leaf, fi, | |
419 | extent_end - end); | |
420 | btrfs_mark_buffer_dirty(leaf); | |
421 | if (disk_bytenr > 0) { | |
422 | inode_sub_bytes(inode, end - key.offset); | |
423 | *hint_byte = disk_bytenr; | |
39279cc3 | 424 | } |
920bbbfb | 425 | break; |
39279cc3 | 426 | } |
771ed689 | 427 | |
920bbbfb YZ |
428 | search_start = extent_end; |
429 | /* | |
430 | * | ---- range to drop ----- | | |
431 | * | -------- extent -------- | | |
432 | */ | |
433 | if (start > key.offset && end >= extent_end) { | |
434 | BUG_ON(del_nr > 0); | |
435 | BUG_ON(extent_type == BTRFS_FILE_EXTENT_INLINE); | |
8c2383c3 | 436 | |
920bbbfb YZ |
437 | btrfs_set_file_extent_num_bytes(leaf, fi, |
438 | start - key.offset); | |
439 | btrfs_mark_buffer_dirty(leaf); | |
440 | if (disk_bytenr > 0) { | |
441 | inode_sub_bytes(inode, extent_end - start); | |
442 | *hint_byte = disk_bytenr; | |
443 | } | |
444 | if (end == extent_end) | |
445 | break; | |
c8b97818 | 446 | |
920bbbfb YZ |
447 | path->slots[0]++; |
448 | goto next_slot; | |
31840ae1 ZY |
449 | } |
450 | ||
920bbbfb YZ |
451 | /* |
452 | * | ---- range to drop ----- | | |
453 | * | ------ extent ------ | | |
454 | */ | |
455 | if (start <= key.offset && end >= extent_end) { | |
456 | if (del_nr == 0) { | |
457 | del_slot = path->slots[0]; | |
458 | del_nr = 1; | |
459 | } else { | |
460 | BUG_ON(del_slot + del_nr != path->slots[0]); | |
461 | del_nr++; | |
462 | } | |
31840ae1 | 463 | |
920bbbfb | 464 | if (extent_type == BTRFS_FILE_EXTENT_INLINE) { |
a76a3cd4 | 465 | inode_sub_bytes(inode, |
920bbbfb YZ |
466 | extent_end - key.offset); |
467 | extent_end = ALIGN(extent_end, | |
468 | root->sectorsize); | |
469 | } else if (disk_bytenr > 0) { | |
31840ae1 | 470 | ret = btrfs_free_extent(trans, root, |
920bbbfb YZ |
471 | disk_bytenr, num_bytes, 0, |
472 | root->root_key.objectid, | |
5d4f98a2 | 473 | key.objectid, key.offset - |
920bbbfb | 474 | extent_offset); |
31840ae1 | 475 | BUG_ON(ret); |
920bbbfb YZ |
476 | inode_sub_bytes(inode, |
477 | extent_end - key.offset); | |
478 | *hint_byte = disk_bytenr; | |
31840ae1 | 479 | } |
31840ae1 | 480 | |
920bbbfb YZ |
481 | if (end == extent_end) |
482 | break; | |
483 | ||
484 | if (path->slots[0] + 1 < btrfs_header_nritems(leaf)) { | |
485 | path->slots[0]++; | |
486 | goto next_slot; | |
487 | } | |
488 | ||
489 | ret = btrfs_del_items(trans, root, path, del_slot, | |
490 | del_nr); | |
491 | BUG_ON(ret); | |
492 | ||
493 | del_nr = 0; | |
494 | del_slot = 0; | |
495 | ||
496 | btrfs_release_path(root, path); | |
497 | continue; | |
39279cc3 | 498 | } |
920bbbfb YZ |
499 | |
500 | BUG_ON(1); | |
39279cc3 | 501 | } |
920bbbfb YZ |
502 | |
503 | if (del_nr > 0) { | |
504 | ret = btrfs_del_items(trans, root, path, del_slot, del_nr); | |
505 | BUG_ON(ret); | |
6643558d | 506 | } |
920bbbfb YZ |
507 | |
508 | btrfs_free_path(path); | |
39279cc3 CM |
509 | return ret; |
510 | } | |
511 | ||
d899e052 YZ |
512 | static int extent_mergeable(struct extent_buffer *leaf, int slot, |
513 | u64 objectid, u64 bytenr, u64 *start, u64 *end) | |
514 | { | |
515 | struct btrfs_file_extent_item *fi; | |
516 | struct btrfs_key key; | |
517 | u64 extent_end; | |
518 | ||
519 | if (slot < 0 || slot >= btrfs_header_nritems(leaf)) | |
520 | return 0; | |
521 | ||
522 | btrfs_item_key_to_cpu(leaf, &key, slot); | |
523 | if (key.objectid != objectid || key.type != BTRFS_EXTENT_DATA_KEY) | |
524 | return 0; | |
525 | ||
526 | fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item); | |
527 | if (btrfs_file_extent_type(leaf, fi) != BTRFS_FILE_EXTENT_REG || | |
528 | btrfs_file_extent_disk_bytenr(leaf, fi) != bytenr || | |
529 | btrfs_file_extent_compression(leaf, fi) || | |
530 | btrfs_file_extent_encryption(leaf, fi) || | |
531 | btrfs_file_extent_other_encoding(leaf, fi)) | |
532 | return 0; | |
533 | ||
534 | extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi); | |
535 | if ((*start && *start != key.offset) || (*end && *end != extent_end)) | |
536 | return 0; | |
537 | ||
538 | *start = key.offset; | |
539 | *end = extent_end; | |
540 | return 1; | |
541 | } | |
542 | ||
543 | /* | |
544 | * Mark extent in the range start - end as written. | |
545 | * | |
546 | * This changes extent type from 'pre-allocated' to 'regular'. If only | |
547 | * part of extent is marked as written, the extent will be split into | |
548 | * two or three. | |
549 | */ | |
550 | int btrfs_mark_extent_written(struct btrfs_trans_handle *trans, | |
d899e052 YZ |
551 | struct inode *inode, u64 start, u64 end) |
552 | { | |
920bbbfb | 553 | struct btrfs_root *root = BTRFS_I(inode)->root; |
d899e052 YZ |
554 | struct extent_buffer *leaf; |
555 | struct btrfs_path *path; | |
556 | struct btrfs_file_extent_item *fi; | |
557 | struct btrfs_key key; | |
920bbbfb | 558 | struct btrfs_key new_key; |
d899e052 YZ |
559 | u64 bytenr; |
560 | u64 num_bytes; | |
561 | u64 extent_end; | |
5d4f98a2 | 562 | u64 orig_offset; |
d899e052 YZ |
563 | u64 other_start; |
564 | u64 other_end; | |
920bbbfb YZ |
565 | u64 split; |
566 | int del_nr = 0; | |
567 | int del_slot = 0; | |
d899e052 YZ |
568 | int ret; |
569 | ||
570 | btrfs_drop_extent_cache(inode, start, end - 1, 0); | |
571 | ||
572 | path = btrfs_alloc_path(); | |
573 | BUG_ON(!path); | |
574 | again: | |
920bbbfb | 575 | split = start; |
d899e052 YZ |
576 | key.objectid = inode->i_ino; |
577 | key.type = BTRFS_EXTENT_DATA_KEY; | |
920bbbfb | 578 | key.offset = split; |
d899e052 YZ |
579 | |
580 | ret = btrfs_search_slot(trans, root, &key, path, -1, 1); | |
581 | if (ret > 0 && path->slots[0] > 0) | |
582 | path->slots[0]--; | |
583 | ||
584 | leaf = path->nodes[0]; | |
585 | btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); | |
586 | BUG_ON(key.objectid != inode->i_ino || | |
587 | key.type != BTRFS_EXTENT_DATA_KEY); | |
588 | fi = btrfs_item_ptr(leaf, path->slots[0], | |
589 | struct btrfs_file_extent_item); | |
920bbbfb YZ |
590 | BUG_ON(btrfs_file_extent_type(leaf, fi) != |
591 | BTRFS_FILE_EXTENT_PREALLOC); | |
d899e052 YZ |
592 | extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi); |
593 | BUG_ON(key.offset > start || extent_end < end); | |
594 | ||
595 | bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); | |
596 | num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi); | |
5d4f98a2 | 597 | orig_offset = key.offset - btrfs_file_extent_offset(leaf, fi); |
d899e052 | 598 | |
920bbbfb YZ |
599 | while (start > key.offset || end < extent_end) { |
600 | if (key.offset == start) | |
601 | split = end; | |
602 | ||
603 | memcpy(&new_key, &key, sizeof(new_key)); | |
604 | new_key.offset = split; | |
605 | ret = btrfs_duplicate_item(trans, root, path, &new_key); | |
606 | if (ret == -EAGAIN) { | |
607 | btrfs_release_path(root, path); | |
608 | goto again; | |
d899e052 | 609 | } |
920bbbfb | 610 | BUG_ON(ret < 0); |
d899e052 | 611 | |
920bbbfb YZ |
612 | leaf = path->nodes[0]; |
613 | fi = btrfs_item_ptr(leaf, path->slots[0] - 1, | |
d899e052 | 614 | struct btrfs_file_extent_item); |
d899e052 | 615 | btrfs_set_file_extent_num_bytes(leaf, fi, |
920bbbfb YZ |
616 | split - key.offset); |
617 | ||
618 | fi = btrfs_item_ptr(leaf, path->slots[0], | |
619 | struct btrfs_file_extent_item); | |
620 | ||
621 | btrfs_set_file_extent_offset(leaf, fi, split - orig_offset); | |
622 | btrfs_set_file_extent_num_bytes(leaf, fi, | |
623 | extent_end - split); | |
d899e052 YZ |
624 | btrfs_mark_buffer_dirty(leaf); |
625 | ||
920bbbfb YZ |
626 | ret = btrfs_inc_extent_ref(trans, root, bytenr, num_bytes, 0, |
627 | root->root_key.objectid, | |
628 | inode->i_ino, orig_offset); | |
d899e052 | 629 | BUG_ON(ret); |
d899e052 | 630 | |
920bbbfb YZ |
631 | if (split == start) { |
632 | key.offset = start; | |
633 | } else { | |
634 | BUG_ON(start != key.offset); | |
d899e052 | 635 | path->slots[0]--; |
920bbbfb | 636 | extent_end = end; |
d899e052 YZ |
637 | } |
638 | } | |
639 | ||
d899e052 YZ |
640 | fi = btrfs_item_ptr(leaf, path->slots[0], |
641 | struct btrfs_file_extent_item); | |
546888da | 642 | |
920bbbfb YZ |
643 | other_start = end; |
644 | other_end = 0; | |
645 | if (extent_mergeable(leaf, path->slots[0] + 1, inode->i_ino, | |
646 | bytenr, &other_start, &other_end)) { | |
647 | extent_end = other_end; | |
648 | del_slot = path->slots[0] + 1; | |
649 | del_nr++; | |
650 | ret = btrfs_free_extent(trans, root, bytenr, num_bytes, | |
651 | 0, root->root_key.objectid, | |
652 | inode->i_ino, orig_offset); | |
653 | BUG_ON(ret); | |
d899e052 | 654 | } |
920bbbfb YZ |
655 | other_start = 0; |
656 | other_end = start; | |
657 | if (extent_mergeable(leaf, path->slots[0] - 1, inode->i_ino, | |
658 | bytenr, &other_start, &other_end)) { | |
659 | key.offset = other_start; | |
660 | del_slot = path->slots[0]; | |
661 | del_nr++; | |
662 | ret = btrfs_free_extent(trans, root, bytenr, num_bytes, | |
663 | 0, root->root_key.objectid, | |
664 | inode->i_ino, orig_offset); | |
665 | BUG_ON(ret); | |
666 | } | |
667 | if (del_nr == 0) { | |
668 | btrfs_set_file_extent_type(leaf, fi, | |
669 | BTRFS_FILE_EXTENT_REG); | |
670 | btrfs_mark_buffer_dirty(leaf); | |
671 | goto out; | |
d899e052 | 672 | } |
920bbbfb YZ |
673 | |
674 | fi = btrfs_item_ptr(leaf, del_slot - 1, | |
675 | struct btrfs_file_extent_item); | |
676 | btrfs_set_file_extent_type(leaf, fi, BTRFS_FILE_EXTENT_REG); | |
677 | btrfs_set_file_extent_num_bytes(leaf, fi, | |
678 | extent_end - key.offset); | |
679 | btrfs_mark_buffer_dirty(leaf); | |
680 | ||
681 | ret = btrfs_del_items(trans, root, path, del_slot, del_nr); | |
682 | BUG_ON(ret); | |
683 | out: | |
d899e052 YZ |
684 | btrfs_free_path(path); |
685 | return 0; | |
686 | } | |
687 | ||
39279cc3 | 688 | /* |
d352ac68 CM |
689 | * this gets pages into the page cache and locks them down, it also properly |
690 | * waits for data=ordered extents to finish before allowing the pages to be | |
691 | * modified. | |
39279cc3 | 692 | */ |
d397712b | 693 | static noinline int prepare_pages(struct btrfs_root *root, struct file *file, |
98ed5174 CM |
694 | struct page **pages, size_t num_pages, |
695 | loff_t pos, unsigned long first_index, | |
696 | unsigned long last_index, size_t write_bytes) | |
39279cc3 CM |
697 | { |
698 | int i; | |
699 | unsigned long index = pos >> PAGE_CACHE_SHIFT; | |
6da6abae | 700 | struct inode *inode = fdentry(file)->d_inode; |
39279cc3 | 701 | int err = 0; |
8c2383c3 | 702 | u64 start_pos; |
e6dcd2dc | 703 | u64 last_pos; |
8c2383c3 | 704 | |
5f39d397 | 705 | start_pos = pos & ~((u64)root->sectorsize - 1); |
e6dcd2dc | 706 | last_pos = ((u64)index + num_pages) << PAGE_CACHE_SHIFT; |
39279cc3 | 707 | |
9036c102 YZ |
708 | if (start_pos > inode->i_size) { |
709 | err = btrfs_cont_expand(inode, start_pos); | |
710 | if (err) | |
711 | return err; | |
712 | } | |
713 | ||
39279cc3 | 714 | memset(pages, 0, num_pages * sizeof(struct page *)); |
e6dcd2dc | 715 | again: |
39279cc3 CM |
716 | for (i = 0; i < num_pages; i++) { |
717 | pages[i] = grab_cache_page(inode->i_mapping, index + i); | |
718 | if (!pages[i]) { | |
719 | err = -ENOMEM; | |
a52d9a80 | 720 | BUG_ON(1); |
39279cc3 | 721 | } |
ccd467d6 | 722 | wait_on_page_writeback(pages[i]); |
39279cc3 | 723 | } |
0762704b | 724 | if (start_pos < inode->i_size) { |
e6dcd2dc | 725 | struct btrfs_ordered_extent *ordered; |
d99cb30a CM |
726 | lock_extent(&BTRFS_I(inode)->io_tree, |
727 | start_pos, last_pos - 1, GFP_NOFS); | |
d397712b CM |
728 | ordered = btrfs_lookup_first_ordered_extent(inode, |
729 | last_pos - 1); | |
e6dcd2dc CM |
730 | if (ordered && |
731 | ordered->file_offset + ordered->len > start_pos && | |
732 | ordered->file_offset < last_pos) { | |
733 | btrfs_put_ordered_extent(ordered); | |
734 | unlock_extent(&BTRFS_I(inode)->io_tree, | |
735 | start_pos, last_pos - 1, GFP_NOFS); | |
736 | for (i = 0; i < num_pages; i++) { | |
737 | unlock_page(pages[i]); | |
738 | page_cache_release(pages[i]); | |
739 | } | |
740 | btrfs_wait_ordered_range(inode, start_pos, | |
741 | last_pos - start_pos); | |
742 | goto again; | |
743 | } | |
744 | if (ordered) | |
745 | btrfs_put_ordered_extent(ordered); | |
746 | ||
0762704b | 747 | clear_extent_bits(&BTRFS_I(inode)->io_tree, start_pos, |
32c00aff JB |
748 | last_pos - 1, EXTENT_DIRTY | EXTENT_DELALLOC | |
749 | EXTENT_DO_ACCOUNTING, | |
0762704b | 750 | GFP_NOFS); |
d99cb30a CM |
751 | unlock_extent(&BTRFS_I(inode)->io_tree, |
752 | start_pos, last_pos - 1, GFP_NOFS); | |
0762704b | 753 | } |
e6dcd2dc | 754 | for (i = 0; i < num_pages; i++) { |
f87f057b | 755 | clear_page_dirty_for_io(pages[i]); |
e6dcd2dc CM |
756 | set_page_extent_mapped(pages[i]); |
757 | WARN_ON(!PageLocked(pages[i])); | |
758 | } | |
39279cc3 | 759 | return 0; |
39279cc3 CM |
760 | } |
761 | ||
762 | static ssize_t btrfs_file_write(struct file *file, const char __user *buf, | |
763 | size_t count, loff_t *ppos) | |
764 | { | |
765 | loff_t pos; | |
2ff3e9b6 CM |
766 | loff_t start_pos; |
767 | ssize_t num_written = 0; | |
768 | ssize_t err = 0; | |
39279cc3 | 769 | int ret = 0; |
6da6abae | 770 | struct inode *inode = fdentry(file)->d_inode; |
39279cc3 | 771 | struct btrfs_root *root = BTRFS_I(inode)->root; |
8c2383c3 CM |
772 | struct page **pages = NULL; |
773 | int nrptrs; | |
39279cc3 CM |
774 | struct page *pinned[2]; |
775 | unsigned long first_index; | |
776 | unsigned long last_index; | |
cb843a6f CM |
777 | int will_write; |
778 | ||
779 | will_write = ((file->f_flags & O_SYNC) || IS_SYNC(inode) || | |
780 | (file->f_flags & O_DIRECT)); | |
8c2383c3 CM |
781 | |
782 | nrptrs = min((count + PAGE_CACHE_SIZE - 1) / PAGE_CACHE_SIZE, | |
783 | PAGE_CACHE_SIZE / (sizeof(struct page *))); | |
39279cc3 CM |
784 | pinned[0] = NULL; |
785 | pinned[1] = NULL; | |
2ff3e9b6 | 786 | |
39279cc3 | 787 | pos = *ppos; |
2ff3e9b6 CM |
788 | start_pos = pos; |
789 | ||
39279cc3 | 790 | vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE); |
ab93dbec CM |
791 | |
792 | /* do the reserve before the mutex lock in case we have to do some | |
793 | * flushing. We wouldn't deadlock, but this is more polite. | |
794 | */ | |
795 | err = btrfs_reserve_metadata_for_delalloc(root, inode, 1); | |
796 | if (err) | |
797 | goto out_nolock; | |
798 | ||
799 | mutex_lock(&inode->i_mutex); | |
800 | ||
39279cc3 CM |
801 | current->backing_dev_info = inode->i_mapping->backing_dev_info; |
802 | err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode)); | |
803 | if (err) | |
ab93dbec CM |
804 | goto out; |
805 | ||
39279cc3 | 806 | if (count == 0) |
ab93dbec | 807 | goto out; |
2b1f55b0 | 808 | |
0ee0fda0 | 809 | err = file_remove_suid(file); |
39279cc3 | 810 | if (err) |
ab93dbec | 811 | goto out; |
9ed74f2d | 812 | |
39279cc3 CM |
813 | file_update_time(file); |
814 | ||
8c2383c3 | 815 | pages = kmalloc(nrptrs * sizeof(struct page *), GFP_KERNEL); |
39279cc3 | 816 | |
ab93dbec CM |
817 | /* generic_write_checks can change our pos */ |
818 | start_pos = pos; | |
819 | ||
c3027eb5 | 820 | BTRFS_I(inode)->sequence++; |
39279cc3 CM |
821 | first_index = pos >> PAGE_CACHE_SHIFT; |
822 | last_index = (pos + count) >> PAGE_CACHE_SHIFT; | |
823 | ||
824 | /* | |
825 | * there are lots of better ways to do this, but this code | |
826 | * makes sure the first and last page in the file range are | |
827 | * up to date and ready for cow | |
828 | */ | |
829 | if ((pos & (PAGE_CACHE_SIZE - 1))) { | |
830 | pinned[0] = grab_cache_page(inode->i_mapping, first_index); | |
831 | if (!PageUptodate(pinned[0])) { | |
9ebefb18 | 832 | ret = btrfs_readpage(NULL, pinned[0]); |
39279cc3 CM |
833 | BUG_ON(ret); |
834 | wait_on_page_locked(pinned[0]); | |
835 | } else { | |
836 | unlock_page(pinned[0]); | |
837 | } | |
838 | } | |
839 | if ((pos + count) & (PAGE_CACHE_SIZE - 1)) { | |
840 | pinned[1] = grab_cache_page(inode->i_mapping, last_index); | |
841 | if (!PageUptodate(pinned[1])) { | |
9ebefb18 | 842 | ret = btrfs_readpage(NULL, pinned[1]); |
39279cc3 CM |
843 | BUG_ON(ret); |
844 | wait_on_page_locked(pinned[1]); | |
845 | } else { | |
846 | unlock_page(pinned[1]); | |
847 | } | |
848 | } | |
849 | ||
d397712b | 850 | while (count > 0) { |
39279cc3 | 851 | size_t offset = pos & (PAGE_CACHE_SIZE - 1); |
11bd143f CM |
852 | size_t write_bytes = min(count, nrptrs * |
853 | (size_t)PAGE_CACHE_SIZE - | |
8c2383c3 | 854 | offset); |
39279cc3 CM |
855 | size_t num_pages = (write_bytes + PAGE_CACHE_SIZE - 1) >> |
856 | PAGE_CACHE_SHIFT; | |
857 | ||
8c2383c3 | 858 | WARN_ON(num_pages > nrptrs); |
9aead435 | 859 | memset(pages, 0, sizeof(struct page *) * nrptrs); |
1832a6d5 | 860 | |
6a63209f | 861 | ret = btrfs_check_data_free_space(root, inode, write_bytes); |
1832a6d5 CM |
862 | if (ret) |
863 | goto out; | |
864 | ||
39279cc3 CM |
865 | ret = prepare_pages(root, file, pages, num_pages, |
866 | pos, first_index, last_index, | |
8c2383c3 | 867 | write_bytes); |
6a63209f JB |
868 | if (ret) { |
869 | btrfs_free_reserved_data_space(root, inode, | |
870 | write_bytes); | |
54aa1f4d | 871 | goto out; |
6a63209f | 872 | } |
39279cc3 | 873 | |
39279cc3 CM |
874 | ret = btrfs_copy_from_user(pos, num_pages, |
875 | write_bytes, pages, buf); | |
54aa1f4d | 876 | if (ret) { |
6a63209f JB |
877 | btrfs_free_reserved_data_space(root, inode, |
878 | write_bytes); | |
54aa1f4d CM |
879 | btrfs_drop_pages(pages, num_pages); |
880 | goto out; | |
881 | } | |
39279cc3 CM |
882 | |
883 | ret = dirty_and_release_pages(NULL, root, file, pages, | |
884 | num_pages, pos, write_bytes); | |
39279cc3 | 885 | btrfs_drop_pages(pages, num_pages); |
6a63209f JB |
886 | if (ret) { |
887 | btrfs_free_reserved_data_space(root, inode, | |
888 | write_bytes); | |
54aa1f4d | 889 | goto out; |
6a63209f | 890 | } |
39279cc3 | 891 | |
cb843a6f | 892 | if (will_write) { |
8aa38c31 CH |
893 | filemap_fdatawrite_range(inode->i_mapping, pos, |
894 | pos + write_bytes - 1); | |
cb843a6f CM |
895 | } else { |
896 | balance_dirty_pages_ratelimited_nr(inode->i_mapping, | |
897 | num_pages); | |
898 | if (num_pages < | |
899 | (root->leafsize >> PAGE_CACHE_SHIFT) + 1) | |
900 | btrfs_btree_balance_dirty(root, 1); | |
901 | btrfs_throttle(root); | |
902 | } | |
903 | ||
39279cc3 CM |
904 | buf += write_bytes; |
905 | count -= write_bytes; | |
906 | pos += write_bytes; | |
907 | num_written += write_bytes; | |
908 | ||
39279cc3 CM |
909 | cond_resched(); |
910 | } | |
39279cc3 | 911 | out: |
1832a6d5 | 912 | mutex_unlock(&inode->i_mutex); |
6a63209f JB |
913 | if (ret) |
914 | err = ret; | |
9ed74f2d | 915 | btrfs_unreserve_metadata_for_delalloc(root, inode, 1); |
5b92ee72 | 916 | |
1832a6d5 | 917 | out_nolock: |
8c2383c3 | 918 | kfree(pages); |
39279cc3 CM |
919 | if (pinned[0]) |
920 | page_cache_release(pinned[0]); | |
921 | if (pinned[1]) | |
922 | page_cache_release(pinned[1]); | |
923 | *ppos = pos; | |
2ff3e9b6 | 924 | |
5a3f23d5 CM |
925 | /* |
926 | * we want to make sure fsync finds this change | |
927 | * but we haven't joined a transaction running right now. | |
928 | * | |
929 | * Later on, someone is sure to update the inode and get the | |
930 | * real transid recorded. | |
931 | * | |
932 | * We set last_trans now to the fs_info generation + 1, | |
933 | * this will either be one more than the running transaction | |
934 | * or the generation used for the next transaction if there isn't | |
935 | * one running right now. | |
936 | */ | |
937 | BTRFS_I(inode)->last_trans = root->fs_info->generation + 1; | |
938 | ||
cb843a6f | 939 | if (num_written > 0 && will_write) { |
e02119d5 CM |
940 | struct btrfs_trans_handle *trans; |
941 | ||
cb843a6f CM |
942 | err = btrfs_wait_ordered_range(inode, start_pos, num_written); |
943 | if (err) | |
2ff3e9b6 | 944 | num_written = err; |
e02119d5 | 945 | |
cb843a6f CM |
946 | if ((file->f_flags & O_SYNC) || IS_SYNC(inode)) { |
947 | trans = btrfs_start_transaction(root, 1); | |
948 | ret = btrfs_log_dentry_safe(trans, root, | |
949 | file->f_dentry); | |
950 | if (ret == 0) { | |
12fcfd22 CM |
951 | ret = btrfs_sync_log(trans, root); |
952 | if (ret == 0) | |
953 | btrfs_end_transaction(trans, root); | |
954 | else | |
955 | btrfs_commit_transaction(trans, root); | |
257c62e1 | 956 | } else if (ret != BTRFS_NO_LOG_SYNC) { |
cb843a6f | 957 | btrfs_commit_transaction(trans, root); |
257c62e1 CM |
958 | } else { |
959 | btrfs_end_transaction(trans, root); | |
cb843a6f CM |
960 | } |
961 | } | |
962 | if (file->f_flags & O_DIRECT) { | |
963 | invalidate_mapping_pages(inode->i_mapping, | |
964 | start_pos >> PAGE_CACHE_SHIFT, | |
965 | (start_pos + num_written - 1) >> PAGE_CACHE_SHIFT); | |
e02119d5 | 966 | } |
2ff3e9b6 | 967 | } |
39279cc3 | 968 | current->backing_dev_info = NULL; |
39279cc3 CM |
969 | return num_written ? num_written : err; |
970 | } | |
971 | ||
d397712b | 972 | int btrfs_release_file(struct inode *inode, struct file *filp) |
e1b81e67 | 973 | { |
5a3f23d5 CM |
974 | /* |
975 | * ordered_data_close is set by settattr when we are about to truncate | |
976 | * a file from a non-zero size to a zero size. This tries to | |
977 | * flush down new bytes that may have been written if the | |
978 | * application were using truncate to replace a file in place. | |
979 | */ | |
980 | if (BTRFS_I(inode)->ordered_data_close) { | |
981 | BTRFS_I(inode)->ordered_data_close = 0; | |
982 | btrfs_add_ordered_operation(NULL, BTRFS_I(inode)->root, inode); | |
983 | if (inode->i_size > BTRFS_ORDERED_OPERATIONS_FLUSH_LIMIT) | |
984 | filemap_flush(inode->i_mapping); | |
985 | } | |
6bf13c0c SW |
986 | if (filp->private_data) |
987 | btrfs_ioctl_trans_end(filp); | |
e1b81e67 M |
988 | return 0; |
989 | } | |
990 | ||
d352ac68 CM |
991 | /* |
992 | * fsync call for both files and directories. This logs the inode into | |
993 | * the tree log instead of forcing full commits whenever possible. | |
994 | * | |
995 | * It needs to call filemap_fdatawait so that all ordered extent updates are | |
996 | * in the metadata btree are up to date for copying to the log. | |
997 | * | |
998 | * It drops the inode mutex before doing the tree log commit. This is an | |
999 | * important optimization for directories because holding the mutex prevents | |
1000 | * new operations on the dir while we write to disk. | |
1001 | */ | |
e02119d5 | 1002 | int btrfs_sync_file(struct file *file, struct dentry *dentry, int datasync) |
39279cc3 CM |
1003 | { |
1004 | struct inode *inode = dentry->d_inode; | |
1005 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
15ee9bc7 | 1006 | int ret = 0; |
39279cc3 CM |
1007 | struct btrfs_trans_handle *trans; |
1008 | ||
257c62e1 CM |
1009 | |
1010 | /* we wait first, since the writeback may change the inode */ | |
1011 | root->log_batch++; | |
1012 | /* the VFS called filemap_fdatawrite for us */ | |
1013 | btrfs_wait_ordered_range(inode, 0, (u64)-1); | |
1014 | root->log_batch++; | |
1015 | ||
39279cc3 | 1016 | /* |
15ee9bc7 JB |
1017 | * check the transaction that last modified this inode |
1018 | * and see if its already been committed | |
39279cc3 | 1019 | */ |
15ee9bc7 JB |
1020 | if (!BTRFS_I(inode)->last_trans) |
1021 | goto out; | |
a2135011 | 1022 | |
257c62e1 CM |
1023 | /* |
1024 | * if the last transaction that changed this file was before | |
1025 | * the current transaction, we can bail out now without any | |
1026 | * syncing | |
1027 | */ | |
15ee9bc7 JB |
1028 | mutex_lock(&root->fs_info->trans_mutex); |
1029 | if (BTRFS_I(inode)->last_trans <= | |
1030 | root->fs_info->last_trans_committed) { | |
1031 | BTRFS_I(inode)->last_trans = 0; | |
1032 | mutex_unlock(&root->fs_info->trans_mutex); | |
1033 | goto out; | |
1034 | } | |
1035 | mutex_unlock(&root->fs_info->trans_mutex); | |
1036 | ||
1037 | /* | |
a52d9a80 CM |
1038 | * ok we haven't committed the transaction yet, lets do a commit |
1039 | */ | |
2cfbd50b | 1040 | if (file && file->private_data) |
6bf13c0c SW |
1041 | btrfs_ioctl_trans_end(file); |
1042 | ||
39279cc3 CM |
1043 | trans = btrfs_start_transaction(root, 1); |
1044 | if (!trans) { | |
1045 | ret = -ENOMEM; | |
1046 | goto out; | |
1047 | } | |
e02119d5 | 1048 | |
2cfbd50b | 1049 | ret = btrfs_log_dentry_safe(trans, root, dentry); |
d397712b | 1050 | if (ret < 0) |
e02119d5 | 1051 | goto out; |
49eb7e46 CM |
1052 | |
1053 | /* we've logged all the items and now have a consistent | |
1054 | * version of the file in the log. It is possible that | |
1055 | * someone will come in and modify the file, but that's | |
1056 | * fine because the log is consistent on disk, and we | |
1057 | * have references to all of the file's extents | |
1058 | * | |
1059 | * It is possible that someone will come in and log the | |
1060 | * file again, but that will end up using the synchronization | |
1061 | * inside btrfs_sync_log to keep things safe. | |
1062 | */ | |
2cfbd50b | 1063 | mutex_unlock(&dentry->d_inode->i_mutex); |
49eb7e46 | 1064 | |
257c62e1 CM |
1065 | if (ret != BTRFS_NO_LOG_SYNC) { |
1066 | if (ret > 0) { | |
12fcfd22 | 1067 | ret = btrfs_commit_transaction(trans, root); |
257c62e1 CM |
1068 | } else { |
1069 | ret = btrfs_sync_log(trans, root); | |
1070 | if (ret == 0) | |
1071 | ret = btrfs_end_transaction(trans, root); | |
1072 | else | |
1073 | ret = btrfs_commit_transaction(trans, root); | |
1074 | } | |
1075 | } else { | |
1076 | ret = btrfs_end_transaction(trans, root); | |
e02119d5 | 1077 | } |
2cfbd50b | 1078 | mutex_lock(&dentry->d_inode->i_mutex); |
39279cc3 CM |
1079 | out: |
1080 | return ret > 0 ? EIO : ret; | |
1081 | } | |
1082 | ||
f0f37e2f | 1083 | static const struct vm_operations_struct btrfs_file_vm_ops = { |
92fee66d | 1084 | .fault = filemap_fault, |
9ebefb18 CM |
1085 | .page_mkwrite = btrfs_page_mkwrite, |
1086 | }; | |
1087 | ||
1088 | static int btrfs_file_mmap(struct file *filp, struct vm_area_struct *vma) | |
1089 | { | |
1090 | vma->vm_ops = &btrfs_file_vm_ops; | |
1091 | file_accessed(filp); | |
1092 | return 0; | |
1093 | } | |
1094 | ||
828c0950 | 1095 | const struct file_operations btrfs_file_operations = { |
39279cc3 CM |
1096 | .llseek = generic_file_llseek, |
1097 | .read = do_sync_read, | |
9ebefb18 | 1098 | .aio_read = generic_file_aio_read, |
e9906a98 | 1099 | .splice_read = generic_file_splice_read, |
39279cc3 | 1100 | .write = btrfs_file_write, |
9ebefb18 | 1101 | .mmap = btrfs_file_mmap, |
39279cc3 | 1102 | .open = generic_file_open, |
e1b81e67 | 1103 | .release = btrfs_release_file, |
39279cc3 | 1104 | .fsync = btrfs_sync_file, |
34287aa3 | 1105 | .unlocked_ioctl = btrfs_ioctl, |
39279cc3 | 1106 | #ifdef CONFIG_COMPAT |
34287aa3 | 1107 | .compat_ioctl = btrfs_ioctl, |
39279cc3 CM |
1108 | #endif |
1109 | }; |