Commit | Line | Data |
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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; |
d1310b2e | 115 | struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; |
db94535d CM |
116 | u64 hint_byte; |
117 | u64 num_bytes; | |
a52d9a80 CM |
118 | u64 start_pos; |
119 | u64 end_of_last_block; | |
120 | u64 end_pos = pos + write_bytes; | |
121 | loff_t isize = i_size_read(inode); | |
39279cc3 | 122 | |
5f39d397 | 123 | start_pos = pos & ~((u64)root->sectorsize - 1); |
db94535d CM |
124 | num_bytes = (write_bytes + pos - start_pos + |
125 | root->sectorsize - 1) & ~((u64)root->sectorsize - 1); | |
39279cc3 | 126 | |
db94535d CM |
127 | end_of_last_block = start_pos + num_bytes - 1; |
128 | ||
d1310b2e | 129 | lock_extent(io_tree, start_pos, end_of_last_block, GFP_NOFS); |
37d1aeee | 130 | trans = btrfs_join_transaction(root, 1); |
a52d9a80 CM |
131 | if (!trans) { |
132 | err = -ENOMEM; | |
133 | goto out_unlock; | |
134 | } | |
135 | btrfs_set_trans_block_group(trans, inode); | |
db94535d | 136 | hint_byte = 0; |
a52d9a80 | 137 | |
d1310b2e | 138 | set_extent_uptodate(io_tree, start_pos, end_of_last_block, GFP_NOFS); |
a52d9a80 | 139 | |
c8b97818 CM |
140 | /* check for reserved extents on each page, we don't want |
141 | * to reset the delalloc bit on things that already have | |
142 | * extents reserved. | |
a52d9a80 | 143 | */ |
c8b97818 CM |
144 | btrfs_set_extent_delalloc(inode, start_pos, end_of_last_block); |
145 | for (i = 0; i < num_pages; i++) { | |
146 | struct page *p = pages[i]; | |
147 | SetPageUptodate(p); | |
148 | ClearPageChecked(p); | |
149 | set_page_dirty(p); | |
a52d9a80 CM |
150 | } |
151 | if (end_pos > isize) { | |
152 | i_size_write(inode, end_pos); | |
f597bb19 CM |
153 | /* we've only changed i_size in ram, and we haven't updated |
154 | * the disk i_size. There is no need to log the inode | |
155 | * at this time. | |
156 | */ | |
39279cc3 | 157 | } |
017e5369 | 158 | err = btrfs_end_transaction(trans, root); |
a52d9a80 | 159 | out_unlock: |
d1310b2e | 160 | unlock_extent(io_tree, start_pos, end_of_last_block, GFP_NOFS); |
39279cc3 CM |
161 | return err; |
162 | } | |
163 | ||
d352ac68 CM |
164 | /* |
165 | * this drops all the extents in the cache that intersect the range | |
166 | * [start, end]. Existing extents are split as required. | |
167 | */ | |
5b21f2ed ZY |
168 | int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end, |
169 | int skip_pinned) | |
a52d9a80 CM |
170 | { |
171 | struct extent_map *em; | |
3b951516 CM |
172 | struct extent_map *split = NULL; |
173 | struct extent_map *split2 = NULL; | |
a52d9a80 | 174 | struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; |
39b5637f | 175 | u64 len = end - start + 1; |
3b951516 CM |
176 | int ret; |
177 | int testend = 1; | |
5b21f2ed | 178 | unsigned long flags; |
c8b97818 | 179 | int compressed = 0; |
a52d9a80 | 180 | |
e6dcd2dc | 181 | WARN_ON(end < start); |
3b951516 | 182 | if (end == (u64)-1) { |
39b5637f | 183 | len = (u64)-1; |
3b951516 CM |
184 | testend = 0; |
185 | } | |
d397712b | 186 | while (1) { |
3b951516 CM |
187 | if (!split) |
188 | split = alloc_extent_map(GFP_NOFS); | |
189 | if (!split2) | |
190 | split2 = alloc_extent_map(GFP_NOFS); | |
191 | ||
d1310b2e | 192 | spin_lock(&em_tree->lock); |
39b5637f | 193 | em = lookup_extent_mapping(em_tree, start, len); |
d1310b2e CM |
194 | if (!em) { |
195 | spin_unlock(&em_tree->lock); | |
a52d9a80 | 196 | break; |
d1310b2e | 197 | } |
5b21f2ed ZY |
198 | flags = em->flags; |
199 | if (skip_pinned && test_bit(EXTENT_FLAG_PINNED, &em->flags)) { | |
200 | spin_unlock(&em_tree->lock); | |
201 | if (em->start <= start && | |
202 | (!testend || em->start + em->len >= start + len)) { | |
203 | free_extent_map(em); | |
204 | break; | |
205 | } | |
206 | if (start < em->start) { | |
207 | len = em->start - start; | |
208 | } else { | |
209 | len = start + len - (em->start + em->len); | |
210 | start = em->start + em->len; | |
211 | } | |
212 | free_extent_map(em); | |
213 | continue; | |
214 | } | |
c8b97818 | 215 | compressed = test_bit(EXTENT_FLAG_COMPRESSED, &em->flags); |
3ce7e67a | 216 | clear_bit(EXTENT_FLAG_PINNED, &em->flags); |
a52d9a80 | 217 | remove_extent_mapping(em_tree, em); |
3b951516 CM |
218 | |
219 | if (em->block_start < EXTENT_MAP_LAST_BYTE && | |
220 | em->start < start) { | |
221 | split->start = em->start; | |
222 | split->len = start - em->start; | |
ff5b7ee3 | 223 | split->orig_start = em->orig_start; |
3b951516 | 224 | split->block_start = em->block_start; |
c8b97818 CM |
225 | |
226 | if (compressed) | |
227 | split->block_len = em->block_len; | |
228 | else | |
229 | split->block_len = split->len; | |
230 | ||
3b951516 | 231 | split->bdev = em->bdev; |
5b21f2ed | 232 | split->flags = flags; |
3b951516 CM |
233 | ret = add_extent_mapping(em_tree, split); |
234 | BUG_ON(ret); | |
235 | free_extent_map(split); | |
236 | split = split2; | |
237 | split2 = NULL; | |
238 | } | |
239 | if (em->block_start < EXTENT_MAP_LAST_BYTE && | |
240 | testend && em->start + em->len > start + len) { | |
241 | u64 diff = start + len - em->start; | |
242 | ||
243 | split->start = start + len; | |
244 | split->len = em->start + em->len - (start + len); | |
245 | split->bdev = em->bdev; | |
5b21f2ed | 246 | split->flags = flags; |
3b951516 | 247 | |
c8b97818 CM |
248 | if (compressed) { |
249 | split->block_len = em->block_len; | |
250 | split->block_start = em->block_start; | |
445a6944 | 251 | split->orig_start = em->orig_start; |
c8b97818 CM |
252 | } else { |
253 | split->block_len = split->len; | |
254 | split->block_start = em->block_start + diff; | |
445a6944 | 255 | split->orig_start = split->start; |
c8b97818 | 256 | } |
3b951516 CM |
257 | |
258 | ret = add_extent_mapping(em_tree, split); | |
259 | BUG_ON(ret); | |
260 | free_extent_map(split); | |
261 | split = NULL; | |
262 | } | |
d1310b2e CM |
263 | spin_unlock(&em_tree->lock); |
264 | ||
a52d9a80 CM |
265 | /* once for us */ |
266 | free_extent_map(em); | |
267 | /* once for the tree*/ | |
268 | free_extent_map(em); | |
269 | } | |
3b951516 CM |
270 | if (split) |
271 | free_extent_map(split); | |
272 | if (split2) | |
273 | free_extent_map(split2); | |
a52d9a80 CM |
274 | return 0; |
275 | } | |
276 | ||
39279cc3 CM |
277 | /* |
278 | * this is very complex, but the basic idea is to drop all extents | |
279 | * in the range start - end. hint_block is filled in with a block number | |
280 | * that would be a good hint to the block allocator for this file. | |
281 | * | |
282 | * If an extent intersects the range but is not entirely inside the range | |
283 | * it is either truncated or split. Anything entirely inside the range | |
284 | * is deleted from the tree. | |
d352ac68 CM |
285 | * |
286 | * inline_limit is used to tell this code which offsets in the file to keep | |
287 | * if they contain inline extents. | |
39279cc3 | 288 | */ |
d397712b | 289 | noinline int btrfs_drop_extents(struct btrfs_trans_handle *trans, |
39279cc3 | 290 | struct btrfs_root *root, struct inode *inode, |
e980b50c CM |
291 | u64 start, u64 end, u64 locked_end, |
292 | u64 inline_limit, u64 *hint_byte) | |
39279cc3 | 293 | { |
00f5c795 CM |
294 | u64 extent_end = 0; |
295 | u64 search_start = start; | |
c8b97818 | 296 | u64 ram_bytes = 0; |
771ed689 | 297 | u64 disk_bytenr = 0; |
e980b50c | 298 | u64 orig_locked_end = locked_end; |
70b99e69 CM |
299 | u8 compression; |
300 | u8 encryption; | |
c8b97818 | 301 | u16 other_encoding = 0; |
5f39d397 | 302 | struct extent_buffer *leaf; |
39279cc3 | 303 | struct btrfs_file_extent_item *extent; |
39279cc3 | 304 | struct btrfs_path *path; |
00f5c795 CM |
305 | struct btrfs_key key; |
306 | struct btrfs_file_extent_item old; | |
307 | int keep; | |
308 | int slot; | |
39279cc3 | 309 | int bookend; |
d899e052 | 310 | int found_type = 0; |
39279cc3 CM |
311 | int found_extent; |
312 | int found_inline; | |
ccd467d6 | 313 | int recow; |
00f5c795 | 314 | int ret; |
39279cc3 | 315 | |
c8b97818 | 316 | inline_limit = 0; |
5b21f2ed | 317 | btrfs_drop_extent_cache(inode, start, end - 1, 0); |
a52d9a80 | 318 | |
39279cc3 CM |
319 | path = btrfs_alloc_path(); |
320 | if (!path) | |
321 | return -ENOMEM; | |
d397712b | 322 | while (1) { |
ccd467d6 | 323 | recow = 0; |
39279cc3 CM |
324 | btrfs_release_path(root, path); |
325 | ret = btrfs_lookup_file_extent(trans, root, path, inode->i_ino, | |
326 | search_start, -1); | |
327 | if (ret < 0) | |
328 | goto out; | |
329 | if (ret > 0) { | |
330 | if (path->slots[0] == 0) { | |
331 | ret = 0; | |
332 | goto out; | |
333 | } | |
334 | path->slots[0]--; | |
335 | } | |
8c2383c3 | 336 | next_slot: |
39279cc3 CM |
337 | keep = 0; |
338 | bookend = 0; | |
339 | found_extent = 0; | |
340 | found_inline = 0; | |
70b99e69 CM |
341 | compression = 0; |
342 | encryption = 0; | |
39279cc3 | 343 | extent = NULL; |
5f39d397 | 344 | leaf = path->nodes[0]; |
39279cc3 | 345 | slot = path->slots[0]; |
8c2383c3 | 346 | ret = 0; |
5f39d397 | 347 | btrfs_item_key_to_cpu(leaf, &key, slot); |
7261009c Y |
348 | if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY && |
349 | key.offset >= end) { | |
39279cc3 CM |
350 | goto out; |
351 | } | |
7261009c Y |
352 | if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY || |
353 | key.objectid != inode->i_ino) { | |
39279cc3 CM |
354 | goto out; |
355 | } | |
ccd467d6 | 356 | if (recow) { |
8247b41a | 357 | search_start = max(key.offset, start); |
ccd467d6 CM |
358 | continue; |
359 | } | |
8c2383c3 CM |
360 | if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) { |
361 | extent = btrfs_item_ptr(leaf, slot, | |
362 | struct btrfs_file_extent_item); | |
5f39d397 | 363 | found_type = btrfs_file_extent_type(leaf, extent); |
c8b97818 CM |
364 | compression = btrfs_file_extent_compression(leaf, |
365 | extent); | |
366 | encryption = btrfs_file_extent_encryption(leaf, | |
367 | extent); | |
368 | other_encoding = btrfs_file_extent_other_encoding(leaf, | |
369 | extent); | |
d899e052 YZ |
370 | if (found_type == BTRFS_FILE_EXTENT_REG || |
371 | found_type == BTRFS_FILE_EXTENT_PREALLOC) { | |
257d0ce3 CM |
372 | extent_end = |
373 | btrfs_file_extent_disk_bytenr(leaf, | |
374 | extent); | |
375 | if (extent_end) | |
376 | *hint_byte = extent_end; | |
377 | ||
8c2383c3 | 378 | extent_end = key.offset + |
db94535d | 379 | btrfs_file_extent_num_bytes(leaf, extent); |
c8b97818 CM |
380 | ram_bytes = btrfs_file_extent_ram_bytes(leaf, |
381 | extent); | |
8c2383c3 CM |
382 | found_extent = 1; |
383 | } else if (found_type == BTRFS_FILE_EXTENT_INLINE) { | |
384 | found_inline = 1; | |
385 | extent_end = key.offset + | |
c8b97818 | 386 | btrfs_file_extent_inline_len(leaf, extent); |
8c2383c3 CM |
387 | } |
388 | } else { | |
389 | extent_end = search_start; | |
39279cc3 CM |
390 | } |
391 | ||
392 | /* we found nothing we can drop */ | |
8c2383c3 CM |
393 | if ((!found_extent && !found_inline) || |
394 | search_start >= extent_end) { | |
395 | int nextret; | |
396 | u32 nritems; | |
5f39d397 | 397 | nritems = btrfs_header_nritems(leaf); |
8c2383c3 CM |
398 | if (slot >= nritems - 1) { |
399 | nextret = btrfs_next_leaf(root, path); | |
400 | if (nextret) | |
401 | goto out; | |
ccd467d6 | 402 | recow = 1; |
8c2383c3 CM |
403 | } else { |
404 | path->slots[0]++; | |
405 | } | |
406 | goto next_slot; | |
39279cc3 CM |
407 | } |
408 | ||
c8b97818 | 409 | if (end <= extent_end && start >= key.offset && found_inline) |
179e29e4 | 410 | *hint_byte = EXTENT_MAP_INLINE; |
31840ae1 ZY |
411 | |
412 | if (found_extent) { | |
413 | read_extent_buffer(leaf, &old, (unsigned long)extent, | |
414 | sizeof(old)); | |
179e29e4 | 415 | } |
31840ae1 | 416 | |
39279cc3 | 417 | if (end < extent_end && end >= key.offset) { |
179e29e4 | 418 | bookend = 1; |
0181e58f | 419 | if (found_inline && start <= key.offset) |
179e29e4 | 420 | keep = 1; |
39279cc3 | 421 | } |
6643558d | 422 | |
771ed689 CM |
423 | if (bookend && found_extent) { |
424 | if (locked_end < extent_end) { | |
425 | ret = try_lock_extent(&BTRFS_I(inode)->io_tree, | |
426 | locked_end, extent_end - 1, | |
427 | GFP_NOFS); | |
428 | if (!ret) { | |
429 | btrfs_release_path(root, path); | |
430 | lock_extent(&BTRFS_I(inode)->io_tree, | |
431 | locked_end, extent_end - 1, | |
432 | GFP_NOFS); | |
433 | locked_end = extent_end; | |
434 | continue; | |
435 | } | |
6643558d | 436 | locked_end = extent_end; |
6643558d | 437 | } |
771ed689 CM |
438 | disk_bytenr = le64_to_cpu(old.disk_bytenr); |
439 | if (disk_bytenr != 0) { | |
440 | ret = btrfs_inc_extent_ref(trans, root, | |
441 | disk_bytenr, | |
5d4f98a2 YZ |
442 | le64_to_cpu(old.disk_num_bytes), 0, |
443 | root->root_key.objectid, | |
444 | key.objectid, key.offset - | |
445 | le64_to_cpu(old.offset)); | |
771ed689 CM |
446 | BUG_ON(ret); |
447 | } | |
6643558d YZ |
448 | } |
449 | ||
450 | if (found_inline) { | |
451 | u64 mask = root->sectorsize - 1; | |
452 | search_start = (extent_end + mask) & ~mask; | |
453 | } else | |
454 | search_start = extent_end; | |
455 | ||
39279cc3 CM |
456 | /* truncate existing extent */ |
457 | if (start > key.offset) { | |
458 | u64 new_num; | |
459 | u64 old_num; | |
460 | keep = 1; | |
5f39d397 | 461 | WARN_ON(start & (root->sectorsize - 1)); |
39279cc3 | 462 | if (found_extent) { |
db94535d CM |
463 | new_num = start - key.offset; |
464 | old_num = btrfs_file_extent_num_bytes(leaf, | |
465 | extent); | |
466 | *hint_byte = | |
467 | btrfs_file_extent_disk_bytenr(leaf, | |
468 | extent); | |
469 | if (btrfs_file_extent_disk_bytenr(leaf, | |
470 | extent)) { | |
a76a3cd4 YZ |
471 | inode_sub_bytes(inode, old_num - |
472 | new_num); | |
39279cc3 | 473 | } |
771ed689 CM |
474 | btrfs_set_file_extent_num_bytes(leaf, |
475 | extent, new_num); | |
5f39d397 | 476 | btrfs_mark_buffer_dirty(leaf); |
00f5c795 CM |
477 | } else if (key.offset < inline_limit && |
478 | (end > extent_end) && | |
479 | (inline_limit < extent_end)) { | |
3326d1b0 CM |
480 | u32 new_size; |
481 | new_size = btrfs_file_extent_calc_inline_size( | |
00f5c795 | 482 | inline_limit - key.offset); |
a76a3cd4 YZ |
483 | inode_sub_bytes(inode, extent_end - |
484 | inline_limit); | |
70b99e69 CM |
485 | btrfs_set_file_extent_ram_bytes(leaf, extent, |
486 | new_size); | |
487 | if (!compression && !encryption) { | |
488 | btrfs_truncate_item(trans, root, path, | |
489 | new_size, 1); | |
490 | } | |
39279cc3 CM |
491 | } |
492 | } | |
493 | /* delete the entire extent */ | |
494 | if (!keep) { | |
a76a3cd4 YZ |
495 | if (found_inline) |
496 | inode_sub_bytes(inode, extent_end - | |
497 | key.offset); | |
39279cc3 | 498 | ret = btrfs_del_item(trans, root, path); |
54aa1f4d | 499 | /* TODO update progress marker and return */ |
39279cc3 | 500 | BUG_ON(ret); |
39279cc3 | 501 | extent = NULL; |
31840ae1 ZY |
502 | btrfs_release_path(root, path); |
503 | /* the extent will be freed later */ | |
39279cc3 | 504 | } |
0181e58f | 505 | if (bookend && found_inline && start <= key.offset) { |
179e29e4 CM |
506 | u32 new_size; |
507 | new_size = btrfs_file_extent_calc_inline_size( | |
0181e58f | 508 | extent_end - end); |
a76a3cd4 | 509 | inode_sub_bytes(inode, end - key.offset); |
70b99e69 CM |
510 | btrfs_set_file_extent_ram_bytes(leaf, extent, |
511 | new_size); | |
512 | if (!compression && !encryption) | |
513 | ret = btrfs_truncate_item(trans, root, path, | |
514 | new_size, 0); | |
31840ae1 | 515 | BUG_ON(ret); |
179e29e4 | 516 | } |
39279cc3 CM |
517 | /* create bookend, splitting the extent in two */ |
518 | if (bookend && found_extent) { | |
519 | struct btrfs_key ins; | |
520 | ins.objectid = inode->i_ino; | |
521 | ins.offset = end; | |
39279cc3 | 522 | btrfs_set_key_type(&ins, BTRFS_EXTENT_DATA_KEY); |
771ed689 | 523 | |
39279cc3 | 524 | btrfs_release_path(root, path); |
b9473439 | 525 | path->leave_spinning = 1; |
39279cc3 CM |
526 | ret = btrfs_insert_empty_item(trans, root, path, &ins, |
527 | sizeof(*extent)); | |
31840ae1 | 528 | BUG_ON(ret); |
8c2383c3 | 529 | |
5f39d397 | 530 | leaf = path->nodes[0]; |
5f39d397 CM |
531 | extent = btrfs_item_ptr(leaf, path->slots[0], |
532 | struct btrfs_file_extent_item); | |
533 | write_extent_buffer(leaf, &old, | |
534 | (unsigned long)extent, sizeof(old)); | |
535 | ||
c8b97818 CM |
536 | btrfs_set_file_extent_compression(leaf, extent, |
537 | compression); | |
538 | btrfs_set_file_extent_encryption(leaf, extent, | |
539 | encryption); | |
540 | btrfs_set_file_extent_other_encoding(leaf, extent, | |
541 | other_encoding); | |
5f39d397 | 542 | btrfs_set_file_extent_offset(leaf, extent, |
db94535d CM |
543 | le64_to_cpu(old.offset) + end - key.offset); |
544 | WARN_ON(le64_to_cpu(old.num_bytes) < | |
545 | (extent_end - end)); | |
546 | btrfs_set_file_extent_num_bytes(leaf, extent, | |
547 | extent_end - end); | |
c8b97818 CM |
548 | |
549 | /* | |
550 | * set the ram bytes to the size of the full extent | |
551 | * before splitting. This is a worst case flag, | |
552 | * but its the best we can do because we don't know | |
553 | * how splitting affects compression | |
554 | */ | |
555 | btrfs_set_file_extent_ram_bytes(leaf, extent, | |
556 | ram_bytes); | |
d899e052 | 557 | btrfs_set_file_extent_type(leaf, extent, found_type); |
db94535d | 558 | |
b9473439 | 559 | btrfs_unlock_up_safe(path, 1); |
39279cc3 | 560 | btrfs_mark_buffer_dirty(path->nodes[0]); |
b9473439 | 561 | btrfs_set_lock_blocking(path->nodes[0]); |
31840ae1 | 562 | |
b9473439 | 563 | path->leave_spinning = 0; |
31840ae1 | 564 | btrfs_release_path(root, path); |
d397712b | 565 | if (disk_bytenr != 0) |
a76a3cd4 | 566 | inode_add_bytes(inode, extent_end - end); |
31840ae1 ZY |
567 | } |
568 | ||
569 | if (found_extent && !keep) { | |
6e430f94 | 570 | u64 old_disk_bytenr = le64_to_cpu(old.disk_bytenr); |
31840ae1 | 571 | |
6e430f94 | 572 | if (old_disk_bytenr != 0) { |
a76a3cd4 YZ |
573 | inode_sub_bytes(inode, |
574 | le64_to_cpu(old.num_bytes)); | |
31840ae1 | 575 | ret = btrfs_free_extent(trans, root, |
6e430f94 | 576 | old_disk_bytenr, |
31840ae1 | 577 | le64_to_cpu(old.disk_num_bytes), |
5d4f98a2 YZ |
578 | 0, root->root_key.objectid, |
579 | key.objectid, key.offset - | |
580 | le64_to_cpu(old.offset)); | |
31840ae1 | 581 | BUG_ON(ret); |
6e430f94 | 582 | *hint_byte = old_disk_bytenr; |
31840ae1 ZY |
583 | } |
584 | } | |
585 | ||
586 | if (search_start >= end) { | |
39279cc3 CM |
587 | ret = 0; |
588 | goto out; | |
589 | } | |
590 | } | |
591 | out: | |
592 | btrfs_free_path(path); | |
e980b50c CM |
593 | if (locked_end > orig_locked_end) { |
594 | unlock_extent(&BTRFS_I(inode)->io_tree, orig_locked_end, | |
595 | locked_end - 1, GFP_NOFS); | |
6643558d | 596 | } |
39279cc3 CM |
597 | return ret; |
598 | } | |
599 | ||
d899e052 YZ |
600 | static int extent_mergeable(struct extent_buffer *leaf, int slot, |
601 | u64 objectid, u64 bytenr, u64 *start, u64 *end) | |
602 | { | |
603 | struct btrfs_file_extent_item *fi; | |
604 | struct btrfs_key key; | |
605 | u64 extent_end; | |
606 | ||
607 | if (slot < 0 || slot >= btrfs_header_nritems(leaf)) | |
608 | return 0; | |
609 | ||
610 | btrfs_item_key_to_cpu(leaf, &key, slot); | |
611 | if (key.objectid != objectid || key.type != BTRFS_EXTENT_DATA_KEY) | |
612 | return 0; | |
613 | ||
614 | fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item); | |
615 | if (btrfs_file_extent_type(leaf, fi) != BTRFS_FILE_EXTENT_REG || | |
616 | btrfs_file_extent_disk_bytenr(leaf, fi) != bytenr || | |
617 | btrfs_file_extent_compression(leaf, fi) || | |
618 | btrfs_file_extent_encryption(leaf, fi) || | |
619 | btrfs_file_extent_other_encoding(leaf, fi)) | |
620 | return 0; | |
621 | ||
622 | extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi); | |
623 | if ((*start && *start != key.offset) || (*end && *end != extent_end)) | |
624 | return 0; | |
625 | ||
626 | *start = key.offset; | |
627 | *end = extent_end; | |
628 | return 1; | |
629 | } | |
630 | ||
631 | /* | |
632 | * Mark extent in the range start - end as written. | |
633 | * | |
634 | * This changes extent type from 'pre-allocated' to 'regular'. If only | |
635 | * part of extent is marked as written, the extent will be split into | |
636 | * two or three. | |
637 | */ | |
638 | int btrfs_mark_extent_written(struct btrfs_trans_handle *trans, | |
639 | struct btrfs_root *root, | |
640 | struct inode *inode, u64 start, u64 end) | |
641 | { | |
642 | struct extent_buffer *leaf; | |
643 | struct btrfs_path *path; | |
644 | struct btrfs_file_extent_item *fi; | |
645 | struct btrfs_key key; | |
646 | u64 bytenr; | |
647 | u64 num_bytes; | |
648 | u64 extent_end; | |
5d4f98a2 | 649 | u64 orig_offset; |
d899e052 YZ |
650 | u64 other_start; |
651 | u64 other_end; | |
652 | u64 split = start; | |
653 | u64 locked_end = end; | |
654 | int extent_type; | |
655 | int split_end = 1; | |
656 | int ret; | |
657 | ||
658 | btrfs_drop_extent_cache(inode, start, end - 1, 0); | |
659 | ||
660 | path = btrfs_alloc_path(); | |
661 | BUG_ON(!path); | |
662 | again: | |
663 | key.objectid = inode->i_ino; | |
664 | key.type = BTRFS_EXTENT_DATA_KEY; | |
665 | if (split == start) | |
666 | key.offset = split; | |
667 | else | |
668 | key.offset = split - 1; | |
669 | ||
670 | ret = btrfs_search_slot(trans, root, &key, path, -1, 1); | |
671 | if (ret > 0 && path->slots[0] > 0) | |
672 | path->slots[0]--; | |
673 | ||
674 | leaf = path->nodes[0]; | |
675 | btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); | |
676 | BUG_ON(key.objectid != inode->i_ino || | |
677 | key.type != BTRFS_EXTENT_DATA_KEY); | |
678 | fi = btrfs_item_ptr(leaf, path->slots[0], | |
679 | struct btrfs_file_extent_item); | |
680 | extent_type = btrfs_file_extent_type(leaf, fi); | |
681 | BUG_ON(extent_type != BTRFS_FILE_EXTENT_PREALLOC); | |
682 | extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi); | |
683 | BUG_ON(key.offset > start || extent_end < end); | |
684 | ||
685 | bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); | |
686 | num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi); | |
5d4f98a2 | 687 | orig_offset = key.offset - btrfs_file_extent_offset(leaf, fi); |
d899e052 YZ |
688 | |
689 | if (key.offset == start) | |
690 | split = end; | |
691 | ||
692 | if (key.offset == start && extent_end == end) { | |
693 | int del_nr = 0; | |
694 | int del_slot = 0; | |
d899e052 YZ |
695 | other_start = end; |
696 | other_end = 0; | |
697 | if (extent_mergeable(leaf, path->slots[0] + 1, inode->i_ino, | |
698 | bytenr, &other_start, &other_end)) { | |
699 | extent_end = other_end; | |
700 | del_slot = path->slots[0] + 1; | |
701 | del_nr++; | |
702 | ret = btrfs_free_extent(trans, root, bytenr, num_bytes, | |
5d4f98a2 YZ |
703 | 0, root->root_key.objectid, |
704 | inode->i_ino, orig_offset); | |
d899e052 YZ |
705 | BUG_ON(ret); |
706 | } | |
707 | other_start = 0; | |
708 | other_end = start; | |
709 | if (extent_mergeable(leaf, path->slots[0] - 1, inode->i_ino, | |
710 | bytenr, &other_start, &other_end)) { | |
711 | key.offset = other_start; | |
712 | del_slot = path->slots[0]; | |
713 | del_nr++; | |
714 | ret = btrfs_free_extent(trans, root, bytenr, num_bytes, | |
5d4f98a2 YZ |
715 | 0, root->root_key.objectid, |
716 | inode->i_ino, orig_offset); | |
d899e052 YZ |
717 | BUG_ON(ret); |
718 | } | |
719 | split_end = 0; | |
720 | if (del_nr == 0) { | |
721 | btrfs_set_file_extent_type(leaf, fi, | |
722 | BTRFS_FILE_EXTENT_REG); | |
723 | goto done; | |
724 | } | |
725 | ||
726 | fi = btrfs_item_ptr(leaf, del_slot - 1, | |
727 | struct btrfs_file_extent_item); | |
728 | btrfs_set_file_extent_type(leaf, fi, BTRFS_FILE_EXTENT_REG); | |
729 | btrfs_set_file_extent_num_bytes(leaf, fi, | |
730 | extent_end - key.offset); | |
731 | btrfs_mark_buffer_dirty(leaf); | |
732 | ||
733 | ret = btrfs_del_items(trans, root, path, del_slot, del_nr); | |
734 | BUG_ON(ret); | |
546888da | 735 | goto release; |
d899e052 YZ |
736 | } else if (split == start) { |
737 | if (locked_end < extent_end) { | |
738 | ret = try_lock_extent(&BTRFS_I(inode)->io_tree, | |
739 | locked_end, extent_end - 1, GFP_NOFS); | |
740 | if (!ret) { | |
741 | btrfs_release_path(root, path); | |
742 | lock_extent(&BTRFS_I(inode)->io_tree, | |
743 | locked_end, extent_end - 1, GFP_NOFS); | |
744 | locked_end = extent_end; | |
745 | goto again; | |
746 | } | |
747 | locked_end = extent_end; | |
748 | } | |
749 | btrfs_set_file_extent_num_bytes(leaf, fi, split - key.offset); | |
d899e052 YZ |
750 | } else { |
751 | BUG_ON(key.offset != start); | |
d899e052 | 752 | key.offset = split; |
5d4f98a2 YZ |
753 | btrfs_set_file_extent_offset(leaf, fi, key.offset - |
754 | orig_offset); | |
755 | btrfs_set_file_extent_num_bytes(leaf, fi, extent_end - split); | |
d899e052 YZ |
756 | btrfs_set_item_key_safe(trans, root, path, &key); |
757 | extent_end = split; | |
758 | } | |
759 | ||
760 | if (extent_end == end) { | |
761 | split_end = 0; | |
762 | extent_type = BTRFS_FILE_EXTENT_REG; | |
763 | } | |
764 | if (extent_end == end && split == start) { | |
765 | other_start = end; | |
766 | other_end = 0; | |
767 | if (extent_mergeable(leaf, path->slots[0] + 1, inode->i_ino, | |
768 | bytenr, &other_start, &other_end)) { | |
769 | path->slots[0]++; | |
770 | fi = btrfs_item_ptr(leaf, path->slots[0], | |
771 | struct btrfs_file_extent_item); | |
772 | key.offset = split; | |
773 | btrfs_set_item_key_safe(trans, root, path, &key); | |
5d4f98a2 YZ |
774 | btrfs_set_file_extent_offset(leaf, fi, key.offset - |
775 | orig_offset); | |
d899e052 YZ |
776 | btrfs_set_file_extent_num_bytes(leaf, fi, |
777 | other_end - split); | |
778 | goto done; | |
779 | } | |
780 | } | |
781 | if (extent_end == end && split == end) { | |
782 | other_start = 0; | |
783 | other_end = start; | |
784 | if (extent_mergeable(leaf, path->slots[0] - 1 , inode->i_ino, | |
785 | bytenr, &other_start, &other_end)) { | |
786 | path->slots[0]--; | |
787 | fi = btrfs_item_ptr(leaf, path->slots[0], | |
788 | struct btrfs_file_extent_item); | |
789 | btrfs_set_file_extent_num_bytes(leaf, fi, extent_end - | |
790 | other_start); | |
791 | goto done; | |
792 | } | |
793 | } | |
794 | ||
795 | btrfs_mark_buffer_dirty(leaf); | |
c36047d7 | 796 | |
5d4f98a2 YZ |
797 | ret = btrfs_inc_extent_ref(trans, root, bytenr, num_bytes, 0, |
798 | root->root_key.objectid, | |
799 | inode->i_ino, orig_offset); | |
c36047d7 | 800 | BUG_ON(ret); |
d899e052 YZ |
801 | btrfs_release_path(root, path); |
802 | ||
803 | key.offset = start; | |
804 | ret = btrfs_insert_empty_item(trans, root, path, &key, sizeof(*fi)); | |
805 | BUG_ON(ret); | |
806 | ||
807 | leaf = path->nodes[0]; | |
808 | fi = btrfs_item_ptr(leaf, path->slots[0], | |
809 | struct btrfs_file_extent_item); | |
810 | btrfs_set_file_extent_generation(leaf, fi, trans->transid); | |
811 | btrfs_set_file_extent_type(leaf, fi, extent_type); | |
812 | btrfs_set_file_extent_disk_bytenr(leaf, fi, bytenr); | |
813 | btrfs_set_file_extent_disk_num_bytes(leaf, fi, num_bytes); | |
5d4f98a2 | 814 | btrfs_set_file_extent_offset(leaf, fi, key.offset - orig_offset); |
d899e052 YZ |
815 | btrfs_set_file_extent_num_bytes(leaf, fi, extent_end - key.offset); |
816 | btrfs_set_file_extent_ram_bytes(leaf, fi, num_bytes); | |
817 | btrfs_set_file_extent_compression(leaf, fi, 0); | |
818 | btrfs_set_file_extent_encryption(leaf, fi, 0); | |
819 | btrfs_set_file_extent_other_encoding(leaf, fi, 0); | |
d899e052 YZ |
820 | done: |
821 | btrfs_mark_buffer_dirty(leaf); | |
546888da CM |
822 | |
823 | release: | |
d899e052 YZ |
824 | btrfs_release_path(root, path); |
825 | if (split_end && split == start) { | |
826 | split = end; | |
827 | goto again; | |
828 | } | |
829 | if (locked_end > end) { | |
830 | unlock_extent(&BTRFS_I(inode)->io_tree, end, locked_end - 1, | |
831 | GFP_NOFS); | |
832 | } | |
833 | btrfs_free_path(path); | |
834 | return 0; | |
835 | } | |
836 | ||
39279cc3 | 837 | /* |
d352ac68 CM |
838 | * this gets pages into the page cache and locks them down, it also properly |
839 | * waits for data=ordered extents to finish before allowing the pages to be | |
840 | * modified. | |
39279cc3 | 841 | */ |
d397712b | 842 | static noinline int prepare_pages(struct btrfs_root *root, struct file *file, |
98ed5174 CM |
843 | struct page **pages, size_t num_pages, |
844 | loff_t pos, unsigned long first_index, | |
845 | unsigned long last_index, size_t write_bytes) | |
39279cc3 CM |
846 | { |
847 | int i; | |
848 | unsigned long index = pos >> PAGE_CACHE_SHIFT; | |
6da6abae | 849 | struct inode *inode = fdentry(file)->d_inode; |
39279cc3 | 850 | int err = 0; |
8c2383c3 | 851 | u64 start_pos; |
e6dcd2dc | 852 | u64 last_pos; |
8c2383c3 | 853 | |
5f39d397 | 854 | start_pos = pos & ~((u64)root->sectorsize - 1); |
e6dcd2dc | 855 | last_pos = ((u64)index + num_pages) << PAGE_CACHE_SHIFT; |
39279cc3 | 856 | |
9036c102 YZ |
857 | if (start_pos > inode->i_size) { |
858 | err = btrfs_cont_expand(inode, start_pos); | |
859 | if (err) | |
860 | return err; | |
861 | } | |
862 | ||
39279cc3 | 863 | memset(pages, 0, num_pages * sizeof(struct page *)); |
e6dcd2dc | 864 | again: |
39279cc3 CM |
865 | for (i = 0; i < num_pages; i++) { |
866 | pages[i] = grab_cache_page(inode->i_mapping, index + i); | |
867 | if (!pages[i]) { | |
868 | err = -ENOMEM; | |
a52d9a80 | 869 | BUG_ON(1); |
39279cc3 | 870 | } |
ccd467d6 | 871 | wait_on_page_writeback(pages[i]); |
39279cc3 | 872 | } |
0762704b | 873 | if (start_pos < inode->i_size) { |
e6dcd2dc | 874 | struct btrfs_ordered_extent *ordered; |
d99cb30a CM |
875 | lock_extent(&BTRFS_I(inode)->io_tree, |
876 | start_pos, last_pos - 1, GFP_NOFS); | |
d397712b CM |
877 | ordered = btrfs_lookup_first_ordered_extent(inode, |
878 | last_pos - 1); | |
e6dcd2dc CM |
879 | if (ordered && |
880 | ordered->file_offset + ordered->len > start_pos && | |
881 | ordered->file_offset < last_pos) { | |
882 | btrfs_put_ordered_extent(ordered); | |
883 | unlock_extent(&BTRFS_I(inode)->io_tree, | |
884 | start_pos, last_pos - 1, GFP_NOFS); | |
885 | for (i = 0; i < num_pages; i++) { | |
886 | unlock_page(pages[i]); | |
887 | page_cache_release(pages[i]); | |
888 | } | |
889 | btrfs_wait_ordered_range(inode, start_pos, | |
890 | last_pos - start_pos); | |
891 | goto again; | |
892 | } | |
893 | if (ordered) | |
894 | btrfs_put_ordered_extent(ordered); | |
895 | ||
0762704b CM |
896 | clear_extent_bits(&BTRFS_I(inode)->io_tree, start_pos, |
897 | last_pos - 1, EXTENT_DIRTY | EXTENT_DELALLOC, | |
898 | GFP_NOFS); | |
d99cb30a CM |
899 | unlock_extent(&BTRFS_I(inode)->io_tree, |
900 | start_pos, last_pos - 1, GFP_NOFS); | |
0762704b | 901 | } |
e6dcd2dc | 902 | for (i = 0; i < num_pages; i++) { |
f87f057b | 903 | clear_page_dirty_for_io(pages[i]); |
e6dcd2dc CM |
904 | set_page_extent_mapped(pages[i]); |
905 | WARN_ON(!PageLocked(pages[i])); | |
906 | } | |
39279cc3 | 907 | return 0; |
39279cc3 CM |
908 | } |
909 | ||
910 | static ssize_t btrfs_file_write(struct file *file, const char __user *buf, | |
911 | size_t count, loff_t *ppos) | |
912 | { | |
913 | loff_t pos; | |
2ff3e9b6 CM |
914 | loff_t start_pos; |
915 | ssize_t num_written = 0; | |
916 | ssize_t err = 0; | |
39279cc3 | 917 | int ret = 0; |
6da6abae | 918 | struct inode *inode = fdentry(file)->d_inode; |
39279cc3 | 919 | struct btrfs_root *root = BTRFS_I(inode)->root; |
8c2383c3 CM |
920 | struct page **pages = NULL; |
921 | int nrptrs; | |
39279cc3 CM |
922 | struct page *pinned[2]; |
923 | unsigned long first_index; | |
924 | unsigned long last_index; | |
cb843a6f CM |
925 | int will_write; |
926 | ||
927 | will_write = ((file->f_flags & O_SYNC) || IS_SYNC(inode) || | |
928 | (file->f_flags & O_DIRECT)); | |
8c2383c3 CM |
929 | |
930 | nrptrs = min((count + PAGE_CACHE_SIZE - 1) / PAGE_CACHE_SIZE, | |
931 | PAGE_CACHE_SIZE / (sizeof(struct page *))); | |
39279cc3 CM |
932 | pinned[0] = NULL; |
933 | pinned[1] = NULL; | |
2ff3e9b6 | 934 | |
39279cc3 | 935 | pos = *ppos; |
2ff3e9b6 CM |
936 | start_pos = pos; |
937 | ||
39279cc3 CM |
938 | vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE); |
939 | current->backing_dev_info = inode->i_mapping->backing_dev_info; | |
940 | err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode)); | |
941 | if (err) | |
1832a6d5 | 942 | goto out_nolock; |
39279cc3 | 943 | if (count == 0) |
1832a6d5 | 944 | goto out_nolock; |
2b1f55b0 | 945 | |
0ee0fda0 | 946 | err = file_remove_suid(file); |
39279cc3 | 947 | if (err) |
1832a6d5 | 948 | goto out_nolock; |
39279cc3 CM |
949 | file_update_time(file); |
950 | ||
8c2383c3 | 951 | pages = kmalloc(nrptrs * sizeof(struct page *), GFP_KERNEL); |
39279cc3 CM |
952 | |
953 | mutex_lock(&inode->i_mutex); | |
c3027eb5 | 954 | BTRFS_I(inode)->sequence++; |
39279cc3 CM |
955 | first_index = pos >> PAGE_CACHE_SHIFT; |
956 | last_index = (pos + count) >> PAGE_CACHE_SHIFT; | |
957 | ||
958 | /* | |
959 | * there are lots of better ways to do this, but this code | |
960 | * makes sure the first and last page in the file range are | |
961 | * up to date and ready for cow | |
962 | */ | |
963 | if ((pos & (PAGE_CACHE_SIZE - 1))) { | |
964 | pinned[0] = grab_cache_page(inode->i_mapping, first_index); | |
965 | if (!PageUptodate(pinned[0])) { | |
9ebefb18 | 966 | ret = btrfs_readpage(NULL, pinned[0]); |
39279cc3 CM |
967 | BUG_ON(ret); |
968 | wait_on_page_locked(pinned[0]); | |
969 | } else { | |
970 | unlock_page(pinned[0]); | |
971 | } | |
972 | } | |
973 | if ((pos + count) & (PAGE_CACHE_SIZE - 1)) { | |
974 | pinned[1] = grab_cache_page(inode->i_mapping, last_index); | |
975 | if (!PageUptodate(pinned[1])) { | |
9ebefb18 | 976 | ret = btrfs_readpage(NULL, pinned[1]); |
39279cc3 CM |
977 | BUG_ON(ret); |
978 | wait_on_page_locked(pinned[1]); | |
979 | } else { | |
980 | unlock_page(pinned[1]); | |
981 | } | |
982 | } | |
983 | ||
d397712b | 984 | while (count > 0) { |
39279cc3 | 985 | size_t offset = pos & (PAGE_CACHE_SIZE - 1); |
11bd143f CM |
986 | size_t write_bytes = min(count, nrptrs * |
987 | (size_t)PAGE_CACHE_SIZE - | |
8c2383c3 | 988 | offset); |
39279cc3 CM |
989 | size_t num_pages = (write_bytes + PAGE_CACHE_SIZE - 1) >> |
990 | PAGE_CACHE_SHIFT; | |
991 | ||
8c2383c3 | 992 | WARN_ON(num_pages > nrptrs); |
9aead435 | 993 | memset(pages, 0, sizeof(struct page *) * nrptrs); |
1832a6d5 | 994 | |
6a63209f | 995 | ret = btrfs_check_data_free_space(root, inode, write_bytes); |
1832a6d5 CM |
996 | if (ret) |
997 | goto out; | |
998 | ||
39279cc3 CM |
999 | ret = prepare_pages(root, file, pages, num_pages, |
1000 | pos, first_index, last_index, | |
8c2383c3 | 1001 | write_bytes); |
6a63209f JB |
1002 | if (ret) { |
1003 | btrfs_free_reserved_data_space(root, inode, | |
1004 | write_bytes); | |
54aa1f4d | 1005 | goto out; |
6a63209f | 1006 | } |
39279cc3 | 1007 | |
39279cc3 CM |
1008 | ret = btrfs_copy_from_user(pos, num_pages, |
1009 | write_bytes, pages, buf); | |
54aa1f4d | 1010 | if (ret) { |
6a63209f JB |
1011 | btrfs_free_reserved_data_space(root, inode, |
1012 | write_bytes); | |
54aa1f4d CM |
1013 | btrfs_drop_pages(pages, num_pages); |
1014 | goto out; | |
1015 | } | |
39279cc3 CM |
1016 | |
1017 | ret = dirty_and_release_pages(NULL, root, file, pages, | |
1018 | num_pages, pos, write_bytes); | |
39279cc3 | 1019 | btrfs_drop_pages(pages, num_pages); |
6a63209f JB |
1020 | if (ret) { |
1021 | btrfs_free_reserved_data_space(root, inode, | |
1022 | write_bytes); | |
54aa1f4d | 1023 | goto out; |
6a63209f | 1024 | } |
39279cc3 | 1025 | |
cb843a6f CM |
1026 | if (will_write) { |
1027 | btrfs_fdatawrite_range(inode->i_mapping, pos, | |
1028 | pos + write_bytes - 1, | |
d313d7a3 | 1029 | WB_SYNC_ALL); |
cb843a6f CM |
1030 | } else { |
1031 | balance_dirty_pages_ratelimited_nr(inode->i_mapping, | |
1032 | num_pages); | |
1033 | if (num_pages < | |
1034 | (root->leafsize >> PAGE_CACHE_SHIFT) + 1) | |
1035 | btrfs_btree_balance_dirty(root, 1); | |
1036 | btrfs_throttle(root); | |
1037 | } | |
1038 | ||
39279cc3 CM |
1039 | buf += write_bytes; |
1040 | count -= write_bytes; | |
1041 | pos += write_bytes; | |
1042 | num_written += write_bytes; | |
1043 | ||
39279cc3 CM |
1044 | cond_resched(); |
1045 | } | |
39279cc3 | 1046 | out: |
1832a6d5 | 1047 | mutex_unlock(&inode->i_mutex); |
6a63209f JB |
1048 | if (ret) |
1049 | err = ret; | |
5b92ee72 | 1050 | |
1832a6d5 | 1051 | out_nolock: |
8c2383c3 | 1052 | kfree(pages); |
39279cc3 CM |
1053 | if (pinned[0]) |
1054 | page_cache_release(pinned[0]); | |
1055 | if (pinned[1]) | |
1056 | page_cache_release(pinned[1]); | |
1057 | *ppos = pos; | |
2ff3e9b6 | 1058 | |
5a3f23d5 CM |
1059 | /* |
1060 | * we want to make sure fsync finds this change | |
1061 | * but we haven't joined a transaction running right now. | |
1062 | * | |
1063 | * Later on, someone is sure to update the inode and get the | |
1064 | * real transid recorded. | |
1065 | * | |
1066 | * We set last_trans now to the fs_info generation + 1, | |
1067 | * this will either be one more than the running transaction | |
1068 | * or the generation used for the next transaction if there isn't | |
1069 | * one running right now. | |
1070 | */ | |
1071 | BTRFS_I(inode)->last_trans = root->fs_info->generation + 1; | |
1072 | ||
cb843a6f | 1073 | if (num_written > 0 && will_write) { |
e02119d5 CM |
1074 | struct btrfs_trans_handle *trans; |
1075 | ||
cb843a6f CM |
1076 | err = btrfs_wait_ordered_range(inode, start_pos, num_written); |
1077 | if (err) | |
2ff3e9b6 | 1078 | num_written = err; |
e02119d5 | 1079 | |
cb843a6f CM |
1080 | if ((file->f_flags & O_SYNC) || IS_SYNC(inode)) { |
1081 | trans = btrfs_start_transaction(root, 1); | |
1082 | ret = btrfs_log_dentry_safe(trans, root, | |
1083 | file->f_dentry); | |
1084 | if (ret == 0) { | |
12fcfd22 CM |
1085 | ret = btrfs_sync_log(trans, root); |
1086 | if (ret == 0) | |
1087 | btrfs_end_transaction(trans, root); | |
1088 | else | |
1089 | btrfs_commit_transaction(trans, root); | |
cb843a6f CM |
1090 | } else { |
1091 | btrfs_commit_transaction(trans, root); | |
1092 | } | |
1093 | } | |
1094 | if (file->f_flags & O_DIRECT) { | |
1095 | invalidate_mapping_pages(inode->i_mapping, | |
1096 | start_pos >> PAGE_CACHE_SHIFT, | |
1097 | (start_pos + num_written - 1) >> PAGE_CACHE_SHIFT); | |
e02119d5 | 1098 | } |
2ff3e9b6 | 1099 | } |
39279cc3 | 1100 | current->backing_dev_info = NULL; |
39279cc3 CM |
1101 | return num_written ? num_written : err; |
1102 | } | |
1103 | ||
d397712b | 1104 | int btrfs_release_file(struct inode *inode, struct file *filp) |
e1b81e67 | 1105 | { |
5a3f23d5 CM |
1106 | /* |
1107 | * ordered_data_close is set by settattr when we are about to truncate | |
1108 | * a file from a non-zero size to a zero size. This tries to | |
1109 | * flush down new bytes that may have been written if the | |
1110 | * application were using truncate to replace a file in place. | |
1111 | */ | |
1112 | if (BTRFS_I(inode)->ordered_data_close) { | |
1113 | BTRFS_I(inode)->ordered_data_close = 0; | |
1114 | btrfs_add_ordered_operation(NULL, BTRFS_I(inode)->root, inode); | |
1115 | if (inode->i_size > BTRFS_ORDERED_OPERATIONS_FLUSH_LIMIT) | |
1116 | filemap_flush(inode->i_mapping); | |
1117 | } | |
6bf13c0c SW |
1118 | if (filp->private_data) |
1119 | btrfs_ioctl_trans_end(filp); | |
e1b81e67 M |
1120 | return 0; |
1121 | } | |
1122 | ||
d352ac68 CM |
1123 | /* |
1124 | * fsync call for both files and directories. This logs the inode into | |
1125 | * the tree log instead of forcing full commits whenever possible. | |
1126 | * | |
1127 | * It needs to call filemap_fdatawait so that all ordered extent updates are | |
1128 | * in the metadata btree are up to date for copying to the log. | |
1129 | * | |
1130 | * It drops the inode mutex before doing the tree log commit. This is an | |
1131 | * important optimization for directories because holding the mutex prevents | |
1132 | * new operations on the dir while we write to disk. | |
1133 | */ | |
e02119d5 | 1134 | int btrfs_sync_file(struct file *file, struct dentry *dentry, int datasync) |
39279cc3 CM |
1135 | { |
1136 | struct inode *inode = dentry->d_inode; | |
1137 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
15ee9bc7 | 1138 | int ret = 0; |
39279cc3 CM |
1139 | struct btrfs_trans_handle *trans; |
1140 | ||
1141 | /* | |
15ee9bc7 JB |
1142 | * check the transaction that last modified this inode |
1143 | * and see if its already been committed | |
39279cc3 | 1144 | */ |
15ee9bc7 JB |
1145 | if (!BTRFS_I(inode)->last_trans) |
1146 | goto out; | |
a2135011 | 1147 | |
15ee9bc7 JB |
1148 | mutex_lock(&root->fs_info->trans_mutex); |
1149 | if (BTRFS_I(inode)->last_trans <= | |
1150 | root->fs_info->last_trans_committed) { | |
1151 | BTRFS_I(inode)->last_trans = 0; | |
1152 | mutex_unlock(&root->fs_info->trans_mutex); | |
1153 | goto out; | |
1154 | } | |
1155 | mutex_unlock(&root->fs_info->trans_mutex); | |
1156 | ||
7237f183 | 1157 | root->log_batch++; |
580afd76 CM |
1158 | filemap_fdatawrite(inode->i_mapping); |
1159 | btrfs_wait_ordered_range(inode, 0, (u64)-1); | |
7237f183 | 1160 | root->log_batch++; |
e02119d5 | 1161 | |
524724ed HH |
1162 | if (datasync && !(inode->i_state & I_DIRTY_PAGES)) |
1163 | goto out; | |
15ee9bc7 | 1164 | /* |
a52d9a80 CM |
1165 | * ok we haven't committed the transaction yet, lets do a commit |
1166 | */ | |
2cfbd50b | 1167 | if (file && file->private_data) |
6bf13c0c SW |
1168 | btrfs_ioctl_trans_end(file); |
1169 | ||
39279cc3 CM |
1170 | trans = btrfs_start_transaction(root, 1); |
1171 | if (!trans) { | |
1172 | ret = -ENOMEM; | |
1173 | goto out; | |
1174 | } | |
e02119d5 | 1175 | |
2cfbd50b | 1176 | ret = btrfs_log_dentry_safe(trans, root, dentry); |
d397712b | 1177 | if (ret < 0) |
e02119d5 | 1178 | goto out; |
49eb7e46 CM |
1179 | |
1180 | /* we've logged all the items and now have a consistent | |
1181 | * version of the file in the log. It is possible that | |
1182 | * someone will come in and modify the file, but that's | |
1183 | * fine because the log is consistent on disk, and we | |
1184 | * have references to all of the file's extents | |
1185 | * | |
1186 | * It is possible that someone will come in and log the | |
1187 | * file again, but that will end up using the synchronization | |
1188 | * inside btrfs_sync_log to keep things safe. | |
1189 | */ | |
2cfbd50b | 1190 | mutex_unlock(&dentry->d_inode->i_mutex); |
49eb7e46 | 1191 | |
e02119d5 CM |
1192 | if (ret > 0) { |
1193 | ret = btrfs_commit_transaction(trans, root); | |
1194 | } else { | |
12fcfd22 CM |
1195 | ret = btrfs_sync_log(trans, root); |
1196 | if (ret == 0) | |
1197 | ret = btrfs_end_transaction(trans, root); | |
1198 | else | |
1199 | ret = btrfs_commit_transaction(trans, root); | |
e02119d5 | 1200 | } |
2cfbd50b | 1201 | mutex_lock(&dentry->d_inode->i_mutex); |
39279cc3 CM |
1202 | out: |
1203 | return ret > 0 ? EIO : ret; | |
1204 | } | |
1205 | ||
9ebefb18 | 1206 | static struct vm_operations_struct btrfs_file_vm_ops = { |
92fee66d | 1207 | .fault = filemap_fault, |
9ebefb18 CM |
1208 | .page_mkwrite = btrfs_page_mkwrite, |
1209 | }; | |
1210 | ||
1211 | static int btrfs_file_mmap(struct file *filp, struct vm_area_struct *vma) | |
1212 | { | |
1213 | vma->vm_ops = &btrfs_file_vm_ops; | |
1214 | file_accessed(filp); | |
1215 | return 0; | |
1216 | } | |
1217 | ||
39279cc3 CM |
1218 | struct file_operations btrfs_file_operations = { |
1219 | .llseek = generic_file_llseek, | |
1220 | .read = do_sync_read, | |
9ebefb18 | 1221 | .aio_read = generic_file_aio_read, |
e9906a98 | 1222 | .splice_read = generic_file_splice_read, |
39279cc3 | 1223 | .write = btrfs_file_write, |
9ebefb18 | 1224 | .mmap = btrfs_file_mmap, |
39279cc3 | 1225 | .open = generic_file_open, |
e1b81e67 | 1226 | .release = btrfs_release_file, |
39279cc3 | 1227 | .fsync = btrfs_sync_file, |
34287aa3 | 1228 | .unlocked_ioctl = btrfs_ioctl, |
39279cc3 | 1229 | #ifdef CONFIG_COMPAT |
34287aa3 | 1230 | .compat_ioctl = btrfs_ioctl, |
39279cc3 CM |
1231 | #endif |
1232 | }; |