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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 | ||
19 | #include <linux/kernel.h> | |
20 | #include <linux/bio.h> | |
21 | #include <linux/buffer_head.h> | |
22 | #include <linux/file.h> | |
23 | #include <linux/fs.h> | |
24 | #include <linux/pagemap.h> | |
25 | #include <linux/highmem.h> | |
26 | #include <linux/time.h> | |
27 | #include <linux/init.h> | |
28 | #include <linux/string.h> | |
29 | #include <linux/backing-dev.h> | |
30 | #include <linux/mpage.h> | |
31 | #include <linux/swap.h> | |
32 | #include <linux/writeback.h> | |
33 | #include <linux/statfs.h> | |
34 | #include <linux/compat.h> | |
35 | #include <linux/bit_spinlock.h> | |
36 | #include <linux/xattr.h> | |
37 | #include <linux/posix_acl.h> | |
38 | #include <linux/falloc.h> | |
39 | #include <linux/slab.h> | |
40 | #include "compat.h" | |
41 | #include "ctree.h" | |
42 | #include "disk-io.h" | |
43 | #include "transaction.h" | |
44 | #include "btrfs_inode.h" | |
45 | #include "ioctl.h" | |
46 | #include "print-tree.h" | |
47 | #include "volumes.h" | |
48 | #include "ordered-data.h" | |
49 | #include "xattr.h" | |
50 | #include "tree-log.h" | |
51 | #include "compression.h" | |
52 | #include "locking.h" | |
53 | ||
54 | struct btrfs_iget_args { | |
55 | u64 ino; | |
56 | struct btrfs_root *root; | |
57 | }; | |
58 | ||
59 | static const struct inode_operations btrfs_dir_inode_operations; | |
60 | static const struct inode_operations btrfs_symlink_inode_operations; | |
61 | static const struct inode_operations btrfs_dir_ro_inode_operations; | |
62 | static const struct inode_operations btrfs_special_inode_operations; | |
63 | static const struct inode_operations btrfs_file_inode_operations; | |
64 | static const struct address_space_operations btrfs_aops; | |
65 | static const struct address_space_operations btrfs_symlink_aops; | |
66 | static const struct file_operations btrfs_dir_file_operations; | |
67 | static struct extent_io_ops btrfs_extent_io_ops; | |
68 | ||
69 | static struct kmem_cache *btrfs_inode_cachep; | |
70 | struct kmem_cache *btrfs_trans_handle_cachep; | |
71 | struct kmem_cache *btrfs_transaction_cachep; | |
72 | struct kmem_cache *btrfs_path_cachep; | |
73 | ||
74 | #define S_SHIFT 12 | |
75 | static unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = { | |
76 | [S_IFREG >> S_SHIFT] = BTRFS_FT_REG_FILE, | |
77 | [S_IFDIR >> S_SHIFT] = BTRFS_FT_DIR, | |
78 | [S_IFCHR >> S_SHIFT] = BTRFS_FT_CHRDEV, | |
79 | [S_IFBLK >> S_SHIFT] = BTRFS_FT_BLKDEV, | |
80 | [S_IFIFO >> S_SHIFT] = BTRFS_FT_FIFO, | |
81 | [S_IFSOCK >> S_SHIFT] = BTRFS_FT_SOCK, | |
82 | [S_IFLNK >> S_SHIFT] = BTRFS_FT_SYMLINK, | |
83 | }; | |
84 | ||
85 | static void btrfs_truncate(struct inode *inode); | |
86 | static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end); | |
87 | static noinline int cow_file_range(struct inode *inode, | |
88 | struct page *locked_page, | |
89 | u64 start, u64 end, int *page_started, | |
90 | unsigned long *nr_written, int unlock); | |
91 | ||
92 | static int btrfs_init_inode_security(struct btrfs_trans_handle *trans, | |
93 | struct inode *inode, struct inode *dir) | |
94 | { | |
95 | int err; | |
96 | ||
97 | err = btrfs_init_acl(trans, inode, dir); | |
98 | if (!err) | |
99 | err = btrfs_xattr_security_init(trans, inode, dir); | |
100 | return err; | |
101 | } | |
102 | ||
103 | /* | |
104 | * this does all the hard work for inserting an inline extent into | |
105 | * the btree. The caller should have done a btrfs_drop_extents so that | |
106 | * no overlapping inline items exist in the btree | |
107 | */ | |
108 | static noinline int insert_inline_extent(struct btrfs_trans_handle *trans, | |
109 | struct btrfs_root *root, struct inode *inode, | |
110 | u64 start, size_t size, size_t compressed_size, | |
111 | struct page **compressed_pages) | |
112 | { | |
113 | struct btrfs_key key; | |
114 | struct btrfs_path *path; | |
115 | struct extent_buffer *leaf; | |
116 | struct page *page = NULL; | |
117 | char *kaddr; | |
118 | unsigned long ptr; | |
119 | struct btrfs_file_extent_item *ei; | |
120 | int err = 0; | |
121 | int ret; | |
122 | size_t cur_size = size; | |
123 | size_t datasize; | |
124 | unsigned long offset; | |
125 | int use_compress = 0; | |
126 | ||
127 | if (compressed_size && compressed_pages) { | |
128 | use_compress = 1; | |
129 | cur_size = compressed_size; | |
130 | } | |
131 | ||
132 | path = btrfs_alloc_path(); | |
133 | if (!path) | |
134 | return -ENOMEM; | |
135 | ||
136 | path->leave_spinning = 1; | |
137 | btrfs_set_trans_block_group(trans, inode); | |
138 | ||
139 | key.objectid = inode->i_ino; | |
140 | key.offset = start; | |
141 | btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY); | |
142 | datasize = btrfs_file_extent_calc_inline_size(cur_size); | |
143 | ||
144 | inode_add_bytes(inode, size); | |
145 | ret = btrfs_insert_empty_item(trans, root, path, &key, | |
146 | datasize); | |
147 | BUG_ON(ret); | |
148 | if (ret) { | |
149 | err = ret; | |
150 | goto fail; | |
151 | } | |
152 | leaf = path->nodes[0]; | |
153 | ei = btrfs_item_ptr(leaf, path->slots[0], | |
154 | struct btrfs_file_extent_item); | |
155 | btrfs_set_file_extent_generation(leaf, ei, trans->transid); | |
156 | btrfs_set_file_extent_type(leaf, ei, BTRFS_FILE_EXTENT_INLINE); | |
157 | btrfs_set_file_extent_encryption(leaf, ei, 0); | |
158 | btrfs_set_file_extent_other_encoding(leaf, ei, 0); | |
159 | btrfs_set_file_extent_ram_bytes(leaf, ei, size); | |
160 | ptr = btrfs_file_extent_inline_start(ei); | |
161 | ||
162 | if (use_compress) { | |
163 | struct page *cpage; | |
164 | int i = 0; | |
165 | while (compressed_size > 0) { | |
166 | cpage = compressed_pages[i]; | |
167 | cur_size = min_t(unsigned long, compressed_size, | |
168 | PAGE_CACHE_SIZE); | |
169 | ||
170 | kaddr = kmap_atomic(cpage, KM_USER0); | |
171 | write_extent_buffer(leaf, kaddr, ptr, cur_size); | |
172 | kunmap_atomic(kaddr, KM_USER0); | |
173 | ||
174 | i++; | |
175 | ptr += cur_size; | |
176 | compressed_size -= cur_size; | |
177 | } | |
178 | btrfs_set_file_extent_compression(leaf, ei, | |
179 | BTRFS_COMPRESS_ZLIB); | |
180 | } else { | |
181 | page = find_get_page(inode->i_mapping, | |
182 | start >> PAGE_CACHE_SHIFT); | |
183 | btrfs_set_file_extent_compression(leaf, ei, 0); | |
184 | kaddr = kmap_atomic(page, KM_USER0); | |
185 | offset = start & (PAGE_CACHE_SIZE - 1); | |
186 | write_extent_buffer(leaf, kaddr + offset, ptr, size); | |
187 | kunmap_atomic(kaddr, KM_USER0); | |
188 | page_cache_release(page); | |
189 | } | |
190 | btrfs_mark_buffer_dirty(leaf); | |
191 | btrfs_free_path(path); | |
192 | ||
193 | /* | |
194 | * we're an inline extent, so nobody can | |
195 | * extend the file past i_size without locking | |
196 | * a page we already have locked. | |
197 | * | |
198 | * We must do any isize and inode updates | |
199 | * before we unlock the pages. Otherwise we | |
200 | * could end up racing with unlink. | |
201 | */ | |
202 | BTRFS_I(inode)->disk_i_size = inode->i_size; | |
203 | btrfs_update_inode(trans, root, inode); | |
204 | ||
205 | return 0; | |
206 | fail: | |
207 | btrfs_free_path(path); | |
208 | return err; | |
209 | } | |
210 | ||
211 | ||
212 | /* | |
213 | * conditionally insert an inline extent into the file. This | |
214 | * does the checks required to make sure the data is small enough | |
215 | * to fit as an inline extent. | |
216 | */ | |
217 | static noinline int cow_file_range_inline(struct btrfs_trans_handle *trans, | |
218 | struct btrfs_root *root, | |
219 | struct inode *inode, u64 start, u64 end, | |
220 | size_t compressed_size, | |
221 | struct page **compressed_pages) | |
222 | { | |
223 | u64 isize = i_size_read(inode); | |
224 | u64 actual_end = min(end + 1, isize); | |
225 | u64 inline_len = actual_end - start; | |
226 | u64 aligned_end = (end + root->sectorsize - 1) & | |
227 | ~((u64)root->sectorsize - 1); | |
228 | u64 hint_byte; | |
229 | u64 data_len = inline_len; | |
230 | int ret; | |
231 | ||
232 | if (compressed_size) | |
233 | data_len = compressed_size; | |
234 | ||
235 | if (start > 0 || | |
236 | actual_end >= PAGE_CACHE_SIZE || | |
237 | data_len >= BTRFS_MAX_INLINE_DATA_SIZE(root) || | |
238 | (!compressed_size && | |
239 | (actual_end & (root->sectorsize - 1)) == 0) || | |
240 | end + 1 < isize || | |
241 | data_len > root->fs_info->max_inline) { | |
242 | return 1; | |
243 | } | |
244 | ||
245 | ret = btrfs_drop_extents(trans, inode, start, aligned_end, | |
246 | &hint_byte, 1); | |
247 | BUG_ON(ret); | |
248 | ||
249 | if (isize > actual_end) | |
250 | inline_len = min_t(u64, isize, actual_end); | |
251 | ret = insert_inline_extent(trans, root, inode, start, | |
252 | inline_len, compressed_size, | |
253 | compressed_pages); | |
254 | BUG_ON(ret); | |
255 | btrfs_delalloc_release_metadata(inode, end + 1 - start); | |
256 | btrfs_drop_extent_cache(inode, start, aligned_end - 1, 0); | |
257 | return 0; | |
258 | } | |
259 | ||
260 | struct async_extent { | |
261 | u64 start; | |
262 | u64 ram_size; | |
263 | u64 compressed_size; | |
264 | struct page **pages; | |
265 | unsigned long nr_pages; | |
266 | struct list_head list; | |
267 | }; | |
268 | ||
269 | struct async_cow { | |
270 | struct inode *inode; | |
271 | struct btrfs_root *root; | |
272 | struct page *locked_page; | |
273 | u64 start; | |
274 | u64 end; | |
275 | struct list_head extents; | |
276 | struct btrfs_work work; | |
277 | }; | |
278 | ||
279 | static noinline int add_async_extent(struct async_cow *cow, | |
280 | u64 start, u64 ram_size, | |
281 | u64 compressed_size, | |
282 | struct page **pages, | |
283 | unsigned long nr_pages) | |
284 | { | |
285 | struct async_extent *async_extent; | |
286 | ||
287 | async_extent = kmalloc(sizeof(*async_extent), GFP_NOFS); | |
288 | async_extent->start = start; | |
289 | async_extent->ram_size = ram_size; | |
290 | async_extent->compressed_size = compressed_size; | |
291 | async_extent->pages = pages; | |
292 | async_extent->nr_pages = nr_pages; | |
293 | list_add_tail(&async_extent->list, &cow->extents); | |
294 | return 0; | |
295 | } | |
296 | ||
297 | /* | |
298 | * we create compressed extents in two phases. The first | |
299 | * phase compresses a range of pages that have already been | |
300 | * locked (both pages and state bits are locked). | |
301 | * | |
302 | * This is done inside an ordered work queue, and the compression | |
303 | * is spread across many cpus. The actual IO submission is step | |
304 | * two, and the ordered work queue takes care of making sure that | |
305 | * happens in the same order things were put onto the queue by | |
306 | * writepages and friends. | |
307 | * | |
308 | * If this code finds it can't get good compression, it puts an | |
309 | * entry onto the work queue to write the uncompressed bytes. This | |
310 | * makes sure that both compressed inodes and uncompressed inodes | |
311 | * are written in the same order that pdflush sent them down. | |
312 | */ | |
313 | static noinline int compress_file_range(struct inode *inode, | |
314 | struct page *locked_page, | |
315 | u64 start, u64 end, | |
316 | struct async_cow *async_cow, | |
317 | int *num_added) | |
318 | { | |
319 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
320 | struct btrfs_trans_handle *trans; | |
321 | u64 num_bytes; | |
322 | u64 blocksize = root->sectorsize; | |
323 | u64 actual_end; | |
324 | u64 isize = i_size_read(inode); | |
325 | int ret = 0; | |
326 | struct page **pages = NULL; | |
327 | unsigned long nr_pages; | |
328 | unsigned long nr_pages_ret = 0; | |
329 | unsigned long total_compressed = 0; | |
330 | unsigned long total_in = 0; | |
331 | unsigned long max_compressed = 128 * 1024; | |
332 | unsigned long max_uncompressed = 128 * 1024; | |
333 | int i; | |
334 | int will_compress; | |
335 | ||
336 | actual_end = min_t(u64, isize, end + 1); | |
337 | again: | |
338 | will_compress = 0; | |
339 | nr_pages = (end >> PAGE_CACHE_SHIFT) - (start >> PAGE_CACHE_SHIFT) + 1; | |
340 | nr_pages = min(nr_pages, (128 * 1024UL) / PAGE_CACHE_SIZE); | |
341 | ||
342 | /* | |
343 | * we don't want to send crud past the end of i_size through | |
344 | * compression, that's just a waste of CPU time. So, if the | |
345 | * end of the file is before the start of our current | |
346 | * requested range of bytes, we bail out to the uncompressed | |
347 | * cleanup code that can deal with all of this. | |
348 | * | |
349 | * It isn't really the fastest way to fix things, but this is a | |
350 | * very uncommon corner. | |
351 | */ | |
352 | if (actual_end <= start) | |
353 | goto cleanup_and_bail_uncompressed; | |
354 | ||
355 | total_compressed = actual_end - start; | |
356 | ||
357 | /* we want to make sure that amount of ram required to uncompress | |
358 | * an extent is reasonable, so we limit the total size in ram | |
359 | * of a compressed extent to 128k. This is a crucial number | |
360 | * because it also controls how easily we can spread reads across | |
361 | * cpus for decompression. | |
362 | * | |
363 | * We also want to make sure the amount of IO required to do | |
364 | * a random read is reasonably small, so we limit the size of | |
365 | * a compressed extent to 128k. | |
366 | */ | |
367 | total_compressed = min(total_compressed, max_uncompressed); | |
368 | num_bytes = (end - start + blocksize) & ~(blocksize - 1); | |
369 | num_bytes = max(blocksize, num_bytes); | |
370 | total_in = 0; | |
371 | ret = 0; | |
372 | ||
373 | /* | |
374 | * we do compression for mount -o compress and when the | |
375 | * inode has not been flagged as nocompress. This flag can | |
376 | * change at any time if we discover bad compression ratios. | |
377 | */ | |
378 | if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS) && | |
379 | (btrfs_test_opt(root, COMPRESS) || | |
380 | (BTRFS_I(inode)->force_compress))) { | |
381 | WARN_ON(pages); | |
382 | pages = kzalloc(sizeof(struct page *) * nr_pages, GFP_NOFS); | |
383 | ||
384 | ret = btrfs_zlib_compress_pages(inode->i_mapping, start, | |
385 | total_compressed, pages, | |
386 | nr_pages, &nr_pages_ret, | |
387 | &total_in, | |
388 | &total_compressed, | |
389 | max_compressed); | |
390 | ||
391 | if (!ret) { | |
392 | unsigned long offset = total_compressed & | |
393 | (PAGE_CACHE_SIZE - 1); | |
394 | struct page *page = pages[nr_pages_ret - 1]; | |
395 | char *kaddr; | |
396 | ||
397 | /* zero the tail end of the last page, we might be | |
398 | * sending it down to disk | |
399 | */ | |
400 | if (offset) { | |
401 | kaddr = kmap_atomic(page, KM_USER0); | |
402 | memset(kaddr + offset, 0, | |
403 | PAGE_CACHE_SIZE - offset); | |
404 | kunmap_atomic(kaddr, KM_USER0); | |
405 | } | |
406 | will_compress = 1; | |
407 | } | |
408 | } | |
409 | if (start == 0) { | |
410 | trans = btrfs_join_transaction(root, 1); | |
411 | BUG_ON(!trans); | |
412 | btrfs_set_trans_block_group(trans, inode); | |
413 | trans->block_rsv = &root->fs_info->delalloc_block_rsv; | |
414 | ||
415 | /* lets try to make an inline extent */ | |
416 | if (ret || total_in < (actual_end - start)) { | |
417 | /* we didn't compress the entire range, try | |
418 | * to make an uncompressed inline extent. | |
419 | */ | |
420 | ret = cow_file_range_inline(trans, root, inode, | |
421 | start, end, 0, NULL); | |
422 | } else { | |
423 | /* try making a compressed inline extent */ | |
424 | ret = cow_file_range_inline(trans, root, inode, | |
425 | start, end, | |
426 | total_compressed, pages); | |
427 | } | |
428 | if (ret == 0) { | |
429 | /* | |
430 | * inline extent creation worked, we don't need | |
431 | * to create any more async work items. Unlock | |
432 | * and free up our temp pages. | |
433 | */ | |
434 | extent_clear_unlock_delalloc(inode, | |
435 | &BTRFS_I(inode)->io_tree, | |
436 | start, end, NULL, | |
437 | EXTENT_CLEAR_UNLOCK_PAGE | EXTENT_CLEAR_DIRTY | | |
438 | EXTENT_CLEAR_DELALLOC | | |
439 | EXTENT_SET_WRITEBACK | EXTENT_END_WRITEBACK); | |
440 | ||
441 | btrfs_end_transaction(trans, root); | |
442 | goto free_pages_out; | |
443 | } | |
444 | btrfs_end_transaction(trans, root); | |
445 | } | |
446 | ||
447 | if (will_compress) { | |
448 | /* | |
449 | * we aren't doing an inline extent round the compressed size | |
450 | * up to a block size boundary so the allocator does sane | |
451 | * things | |
452 | */ | |
453 | total_compressed = (total_compressed + blocksize - 1) & | |
454 | ~(blocksize - 1); | |
455 | ||
456 | /* | |
457 | * one last check to make sure the compression is really a | |
458 | * win, compare the page count read with the blocks on disk | |
459 | */ | |
460 | total_in = (total_in + PAGE_CACHE_SIZE - 1) & | |
461 | ~(PAGE_CACHE_SIZE - 1); | |
462 | if (total_compressed >= total_in) { | |
463 | will_compress = 0; | |
464 | } else { | |
465 | num_bytes = total_in; | |
466 | } | |
467 | } | |
468 | if (!will_compress && pages) { | |
469 | /* | |
470 | * the compression code ran but failed to make things smaller, | |
471 | * free any pages it allocated and our page pointer array | |
472 | */ | |
473 | for (i = 0; i < nr_pages_ret; i++) { | |
474 | WARN_ON(pages[i]->mapping); | |
475 | page_cache_release(pages[i]); | |
476 | } | |
477 | kfree(pages); | |
478 | pages = NULL; | |
479 | total_compressed = 0; | |
480 | nr_pages_ret = 0; | |
481 | ||
482 | /* flag the file so we don't compress in the future */ | |
483 | if (!btrfs_test_opt(root, FORCE_COMPRESS) && | |
484 | !(BTRFS_I(inode)->force_compress)) { | |
485 | BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS; | |
486 | } | |
487 | } | |
488 | if (will_compress) { | |
489 | *num_added += 1; | |
490 | ||
491 | /* the async work queues will take care of doing actual | |
492 | * allocation on disk for these compressed pages, | |
493 | * and will submit them to the elevator. | |
494 | */ | |
495 | add_async_extent(async_cow, start, num_bytes, | |
496 | total_compressed, pages, nr_pages_ret); | |
497 | ||
498 | if (start + num_bytes < end && start + num_bytes < actual_end) { | |
499 | start += num_bytes; | |
500 | pages = NULL; | |
501 | cond_resched(); | |
502 | goto again; | |
503 | } | |
504 | } else { | |
505 | cleanup_and_bail_uncompressed: | |
506 | /* | |
507 | * No compression, but we still need to write the pages in | |
508 | * the file we've been given so far. redirty the locked | |
509 | * page if it corresponds to our extent and set things up | |
510 | * for the async work queue to run cow_file_range to do | |
511 | * the normal delalloc dance | |
512 | */ | |
513 | if (page_offset(locked_page) >= start && | |
514 | page_offset(locked_page) <= end) { | |
515 | __set_page_dirty_nobuffers(locked_page); | |
516 | /* unlocked later on in the async handlers */ | |
517 | } | |
518 | add_async_extent(async_cow, start, end - start + 1, 0, NULL, 0); | |
519 | *num_added += 1; | |
520 | } | |
521 | ||
522 | out: | |
523 | return 0; | |
524 | ||
525 | free_pages_out: | |
526 | for (i = 0; i < nr_pages_ret; i++) { | |
527 | WARN_ON(pages[i]->mapping); | |
528 | page_cache_release(pages[i]); | |
529 | } | |
530 | kfree(pages); | |
531 | ||
532 | goto out; | |
533 | } | |
534 | ||
535 | /* | |
536 | * phase two of compressed writeback. This is the ordered portion | |
537 | * of the code, which only gets called in the order the work was | |
538 | * queued. We walk all the async extents created by compress_file_range | |
539 | * and send them down to the disk. | |
540 | */ | |
541 | static noinline int submit_compressed_extents(struct inode *inode, | |
542 | struct async_cow *async_cow) | |
543 | { | |
544 | struct async_extent *async_extent; | |
545 | u64 alloc_hint = 0; | |
546 | struct btrfs_trans_handle *trans; | |
547 | struct btrfs_key ins; | |
548 | struct extent_map *em; | |
549 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
550 | struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; | |
551 | struct extent_io_tree *io_tree; | |
552 | int ret = 0; | |
553 | ||
554 | if (list_empty(&async_cow->extents)) | |
555 | return 0; | |
556 | ||
557 | ||
558 | while (!list_empty(&async_cow->extents)) { | |
559 | async_extent = list_entry(async_cow->extents.next, | |
560 | struct async_extent, list); | |
561 | list_del(&async_extent->list); | |
562 | ||
563 | io_tree = &BTRFS_I(inode)->io_tree; | |
564 | ||
565 | retry: | |
566 | /* did the compression code fall back to uncompressed IO? */ | |
567 | if (!async_extent->pages) { | |
568 | int page_started = 0; | |
569 | unsigned long nr_written = 0; | |
570 | ||
571 | lock_extent(io_tree, async_extent->start, | |
572 | async_extent->start + | |
573 | async_extent->ram_size - 1, GFP_NOFS); | |
574 | ||
575 | /* allocate blocks */ | |
576 | ret = cow_file_range(inode, async_cow->locked_page, | |
577 | async_extent->start, | |
578 | async_extent->start + | |
579 | async_extent->ram_size - 1, | |
580 | &page_started, &nr_written, 0); | |
581 | ||
582 | /* | |
583 | * if page_started, cow_file_range inserted an | |
584 | * inline extent and took care of all the unlocking | |
585 | * and IO for us. Otherwise, we need to submit | |
586 | * all those pages down to the drive. | |
587 | */ | |
588 | if (!page_started && !ret) | |
589 | extent_write_locked_range(io_tree, | |
590 | inode, async_extent->start, | |
591 | async_extent->start + | |
592 | async_extent->ram_size - 1, | |
593 | btrfs_get_extent, | |
594 | WB_SYNC_ALL); | |
595 | kfree(async_extent); | |
596 | cond_resched(); | |
597 | continue; | |
598 | } | |
599 | ||
600 | lock_extent(io_tree, async_extent->start, | |
601 | async_extent->start + async_extent->ram_size - 1, | |
602 | GFP_NOFS); | |
603 | ||
604 | trans = btrfs_join_transaction(root, 1); | |
605 | ret = btrfs_reserve_extent(trans, root, | |
606 | async_extent->compressed_size, | |
607 | async_extent->compressed_size, | |
608 | 0, alloc_hint, | |
609 | (u64)-1, &ins, 1); | |
610 | btrfs_end_transaction(trans, root); | |
611 | ||
612 | if (ret) { | |
613 | int i; | |
614 | for (i = 0; i < async_extent->nr_pages; i++) { | |
615 | WARN_ON(async_extent->pages[i]->mapping); | |
616 | page_cache_release(async_extent->pages[i]); | |
617 | } | |
618 | kfree(async_extent->pages); | |
619 | async_extent->nr_pages = 0; | |
620 | async_extent->pages = NULL; | |
621 | unlock_extent(io_tree, async_extent->start, | |
622 | async_extent->start + | |
623 | async_extent->ram_size - 1, GFP_NOFS); | |
624 | goto retry; | |
625 | } | |
626 | ||
627 | /* | |
628 | * here we're doing allocation and writeback of the | |
629 | * compressed pages | |
630 | */ | |
631 | btrfs_drop_extent_cache(inode, async_extent->start, | |
632 | async_extent->start + | |
633 | async_extent->ram_size - 1, 0); | |
634 | ||
635 | em = alloc_extent_map(GFP_NOFS); | |
636 | em->start = async_extent->start; | |
637 | em->len = async_extent->ram_size; | |
638 | em->orig_start = em->start; | |
639 | ||
640 | em->block_start = ins.objectid; | |
641 | em->block_len = ins.offset; | |
642 | em->bdev = root->fs_info->fs_devices->latest_bdev; | |
643 | set_bit(EXTENT_FLAG_PINNED, &em->flags); | |
644 | set_bit(EXTENT_FLAG_COMPRESSED, &em->flags); | |
645 | ||
646 | while (1) { | |
647 | write_lock(&em_tree->lock); | |
648 | ret = add_extent_mapping(em_tree, em); | |
649 | write_unlock(&em_tree->lock); | |
650 | if (ret != -EEXIST) { | |
651 | free_extent_map(em); | |
652 | break; | |
653 | } | |
654 | btrfs_drop_extent_cache(inode, async_extent->start, | |
655 | async_extent->start + | |
656 | async_extent->ram_size - 1, 0); | |
657 | } | |
658 | ||
659 | ret = btrfs_add_ordered_extent(inode, async_extent->start, | |
660 | ins.objectid, | |
661 | async_extent->ram_size, | |
662 | ins.offset, | |
663 | BTRFS_ORDERED_COMPRESSED); | |
664 | BUG_ON(ret); | |
665 | ||
666 | /* | |
667 | * clear dirty, set writeback and unlock the pages. | |
668 | */ | |
669 | extent_clear_unlock_delalloc(inode, | |
670 | &BTRFS_I(inode)->io_tree, | |
671 | async_extent->start, | |
672 | async_extent->start + | |
673 | async_extent->ram_size - 1, | |
674 | NULL, EXTENT_CLEAR_UNLOCK_PAGE | | |
675 | EXTENT_CLEAR_UNLOCK | | |
676 | EXTENT_CLEAR_DELALLOC | | |
677 | EXTENT_CLEAR_DIRTY | EXTENT_SET_WRITEBACK); | |
678 | ||
679 | ret = btrfs_submit_compressed_write(inode, | |
680 | async_extent->start, | |
681 | async_extent->ram_size, | |
682 | ins.objectid, | |
683 | ins.offset, async_extent->pages, | |
684 | async_extent->nr_pages); | |
685 | ||
686 | BUG_ON(ret); | |
687 | alloc_hint = ins.objectid + ins.offset; | |
688 | kfree(async_extent); | |
689 | cond_resched(); | |
690 | } | |
691 | ||
692 | return 0; | |
693 | } | |
694 | ||
695 | static u64 get_extent_allocation_hint(struct inode *inode, u64 start, | |
696 | u64 num_bytes) | |
697 | { | |
698 | struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; | |
699 | struct extent_map *em; | |
700 | u64 alloc_hint = 0; | |
701 | ||
702 | read_lock(&em_tree->lock); | |
703 | em = search_extent_mapping(em_tree, start, num_bytes); | |
704 | if (em) { | |
705 | /* | |
706 | * if block start isn't an actual block number then find the | |
707 | * first block in this inode and use that as a hint. If that | |
708 | * block is also bogus then just don't worry about it. | |
709 | */ | |
710 | if (em->block_start >= EXTENT_MAP_LAST_BYTE) { | |
711 | free_extent_map(em); | |
712 | em = search_extent_mapping(em_tree, 0, 0); | |
713 | if (em && em->block_start < EXTENT_MAP_LAST_BYTE) | |
714 | alloc_hint = em->block_start; | |
715 | if (em) | |
716 | free_extent_map(em); | |
717 | } else { | |
718 | alloc_hint = em->block_start; | |
719 | free_extent_map(em); | |
720 | } | |
721 | } | |
722 | read_unlock(&em_tree->lock); | |
723 | ||
724 | return alloc_hint; | |
725 | } | |
726 | ||
727 | /* | |
728 | * when extent_io.c finds a delayed allocation range in the file, | |
729 | * the call backs end up in this code. The basic idea is to | |
730 | * allocate extents on disk for the range, and create ordered data structs | |
731 | * in ram to track those extents. | |
732 | * | |
733 | * locked_page is the page that writepage had locked already. We use | |
734 | * it to make sure we don't do extra locks or unlocks. | |
735 | * | |
736 | * *page_started is set to one if we unlock locked_page and do everything | |
737 | * required to start IO on it. It may be clean and already done with | |
738 | * IO when we return. | |
739 | */ | |
740 | static noinline int cow_file_range(struct inode *inode, | |
741 | struct page *locked_page, | |
742 | u64 start, u64 end, int *page_started, | |
743 | unsigned long *nr_written, | |
744 | int unlock) | |
745 | { | |
746 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
747 | struct btrfs_trans_handle *trans; | |
748 | u64 alloc_hint = 0; | |
749 | u64 num_bytes; | |
750 | unsigned long ram_size; | |
751 | u64 disk_num_bytes; | |
752 | u64 cur_alloc_size; | |
753 | u64 blocksize = root->sectorsize; | |
754 | struct btrfs_key ins; | |
755 | struct extent_map *em; | |
756 | struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; | |
757 | int ret = 0; | |
758 | ||
759 | BUG_ON(root == root->fs_info->tree_root); | |
760 | trans = btrfs_join_transaction(root, 1); | |
761 | BUG_ON(!trans); | |
762 | btrfs_set_trans_block_group(trans, inode); | |
763 | trans->block_rsv = &root->fs_info->delalloc_block_rsv; | |
764 | ||
765 | num_bytes = (end - start + blocksize) & ~(blocksize - 1); | |
766 | num_bytes = max(blocksize, num_bytes); | |
767 | disk_num_bytes = num_bytes; | |
768 | ret = 0; | |
769 | ||
770 | if (start == 0) { | |
771 | /* lets try to make an inline extent */ | |
772 | ret = cow_file_range_inline(trans, root, inode, | |
773 | start, end, 0, NULL); | |
774 | if (ret == 0) { | |
775 | extent_clear_unlock_delalloc(inode, | |
776 | &BTRFS_I(inode)->io_tree, | |
777 | start, end, NULL, | |
778 | EXTENT_CLEAR_UNLOCK_PAGE | | |
779 | EXTENT_CLEAR_UNLOCK | | |
780 | EXTENT_CLEAR_DELALLOC | | |
781 | EXTENT_CLEAR_DIRTY | | |
782 | EXTENT_SET_WRITEBACK | | |
783 | EXTENT_END_WRITEBACK); | |
784 | ||
785 | *nr_written = *nr_written + | |
786 | (end - start + PAGE_CACHE_SIZE) / PAGE_CACHE_SIZE; | |
787 | *page_started = 1; | |
788 | ret = 0; | |
789 | goto out; | |
790 | } | |
791 | } | |
792 | ||
793 | BUG_ON(disk_num_bytes > | |
794 | btrfs_super_total_bytes(&root->fs_info->super_copy)); | |
795 | ||
796 | alloc_hint = get_extent_allocation_hint(inode, start, num_bytes); | |
797 | btrfs_drop_extent_cache(inode, start, start + num_bytes - 1, 0); | |
798 | ||
799 | while (disk_num_bytes > 0) { | |
800 | unsigned long op; | |
801 | ||
802 | cur_alloc_size = disk_num_bytes; | |
803 | ret = btrfs_reserve_extent(trans, root, cur_alloc_size, | |
804 | root->sectorsize, 0, alloc_hint, | |
805 | (u64)-1, &ins, 1); | |
806 | BUG_ON(ret); | |
807 | ||
808 | em = alloc_extent_map(GFP_NOFS); | |
809 | em->start = start; | |
810 | em->orig_start = em->start; | |
811 | ram_size = ins.offset; | |
812 | em->len = ins.offset; | |
813 | ||
814 | em->block_start = ins.objectid; | |
815 | em->block_len = ins.offset; | |
816 | em->bdev = root->fs_info->fs_devices->latest_bdev; | |
817 | set_bit(EXTENT_FLAG_PINNED, &em->flags); | |
818 | ||
819 | while (1) { | |
820 | write_lock(&em_tree->lock); | |
821 | ret = add_extent_mapping(em_tree, em); | |
822 | write_unlock(&em_tree->lock); | |
823 | if (ret != -EEXIST) { | |
824 | free_extent_map(em); | |
825 | break; | |
826 | } | |
827 | btrfs_drop_extent_cache(inode, start, | |
828 | start + ram_size - 1, 0); | |
829 | } | |
830 | ||
831 | cur_alloc_size = ins.offset; | |
832 | ret = btrfs_add_ordered_extent(inode, start, ins.objectid, | |
833 | ram_size, cur_alloc_size, 0); | |
834 | BUG_ON(ret); | |
835 | ||
836 | if (root->root_key.objectid == | |
837 | BTRFS_DATA_RELOC_TREE_OBJECTID) { | |
838 | ret = btrfs_reloc_clone_csums(inode, start, | |
839 | cur_alloc_size); | |
840 | BUG_ON(ret); | |
841 | } | |
842 | ||
843 | if (disk_num_bytes < cur_alloc_size) | |
844 | break; | |
845 | ||
846 | /* we're not doing compressed IO, don't unlock the first | |
847 | * page (which the caller expects to stay locked), don't | |
848 | * clear any dirty bits and don't set any writeback bits | |
849 | * | |
850 | * Do set the Private2 bit so we know this page was properly | |
851 | * setup for writepage | |
852 | */ | |
853 | op = unlock ? EXTENT_CLEAR_UNLOCK_PAGE : 0; | |
854 | op |= EXTENT_CLEAR_UNLOCK | EXTENT_CLEAR_DELALLOC | | |
855 | EXTENT_SET_PRIVATE2; | |
856 | ||
857 | extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree, | |
858 | start, start + ram_size - 1, | |
859 | locked_page, op); | |
860 | disk_num_bytes -= cur_alloc_size; | |
861 | num_bytes -= cur_alloc_size; | |
862 | alloc_hint = ins.objectid + ins.offset; | |
863 | start += cur_alloc_size; | |
864 | } | |
865 | out: | |
866 | ret = 0; | |
867 | btrfs_end_transaction(trans, root); | |
868 | ||
869 | return ret; | |
870 | } | |
871 | ||
872 | /* | |
873 | * work queue call back to started compression on a file and pages | |
874 | */ | |
875 | static noinline void async_cow_start(struct btrfs_work *work) | |
876 | { | |
877 | struct async_cow *async_cow; | |
878 | int num_added = 0; | |
879 | async_cow = container_of(work, struct async_cow, work); | |
880 | ||
881 | compress_file_range(async_cow->inode, async_cow->locked_page, | |
882 | async_cow->start, async_cow->end, async_cow, | |
883 | &num_added); | |
884 | if (num_added == 0) | |
885 | async_cow->inode = NULL; | |
886 | } | |
887 | ||
888 | /* | |
889 | * work queue call back to submit previously compressed pages | |
890 | */ | |
891 | static noinline void async_cow_submit(struct btrfs_work *work) | |
892 | { | |
893 | struct async_cow *async_cow; | |
894 | struct btrfs_root *root; | |
895 | unsigned long nr_pages; | |
896 | ||
897 | async_cow = container_of(work, struct async_cow, work); | |
898 | ||
899 | root = async_cow->root; | |
900 | nr_pages = (async_cow->end - async_cow->start + PAGE_CACHE_SIZE) >> | |
901 | PAGE_CACHE_SHIFT; | |
902 | ||
903 | atomic_sub(nr_pages, &root->fs_info->async_delalloc_pages); | |
904 | ||
905 | if (atomic_read(&root->fs_info->async_delalloc_pages) < | |
906 | 5 * 1042 * 1024 && | |
907 | waitqueue_active(&root->fs_info->async_submit_wait)) | |
908 | wake_up(&root->fs_info->async_submit_wait); | |
909 | ||
910 | if (async_cow->inode) | |
911 | submit_compressed_extents(async_cow->inode, async_cow); | |
912 | } | |
913 | ||
914 | static noinline void async_cow_free(struct btrfs_work *work) | |
915 | { | |
916 | struct async_cow *async_cow; | |
917 | async_cow = container_of(work, struct async_cow, work); | |
918 | kfree(async_cow); | |
919 | } | |
920 | ||
921 | static int cow_file_range_async(struct inode *inode, struct page *locked_page, | |
922 | u64 start, u64 end, int *page_started, | |
923 | unsigned long *nr_written) | |
924 | { | |
925 | struct async_cow *async_cow; | |
926 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
927 | unsigned long nr_pages; | |
928 | u64 cur_end; | |
929 | int limit = 10 * 1024 * 1042; | |
930 | ||
931 | clear_extent_bit(&BTRFS_I(inode)->io_tree, start, end, EXTENT_LOCKED, | |
932 | 1, 0, NULL, GFP_NOFS); | |
933 | while (start < end) { | |
934 | async_cow = kmalloc(sizeof(*async_cow), GFP_NOFS); | |
935 | async_cow->inode = inode; | |
936 | async_cow->root = root; | |
937 | async_cow->locked_page = locked_page; | |
938 | async_cow->start = start; | |
939 | ||
940 | if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS) | |
941 | cur_end = end; | |
942 | else | |
943 | cur_end = min(end, start + 512 * 1024 - 1); | |
944 | ||
945 | async_cow->end = cur_end; | |
946 | INIT_LIST_HEAD(&async_cow->extents); | |
947 | ||
948 | async_cow->work.func = async_cow_start; | |
949 | async_cow->work.ordered_func = async_cow_submit; | |
950 | async_cow->work.ordered_free = async_cow_free; | |
951 | async_cow->work.flags = 0; | |
952 | ||
953 | nr_pages = (cur_end - start + PAGE_CACHE_SIZE) >> | |
954 | PAGE_CACHE_SHIFT; | |
955 | atomic_add(nr_pages, &root->fs_info->async_delalloc_pages); | |
956 | ||
957 | btrfs_queue_worker(&root->fs_info->delalloc_workers, | |
958 | &async_cow->work); | |
959 | ||
960 | if (atomic_read(&root->fs_info->async_delalloc_pages) > limit) { | |
961 | wait_event(root->fs_info->async_submit_wait, | |
962 | (atomic_read(&root->fs_info->async_delalloc_pages) < | |
963 | limit)); | |
964 | } | |
965 | ||
966 | while (atomic_read(&root->fs_info->async_submit_draining) && | |
967 | atomic_read(&root->fs_info->async_delalloc_pages)) { | |
968 | wait_event(root->fs_info->async_submit_wait, | |
969 | (atomic_read(&root->fs_info->async_delalloc_pages) == | |
970 | 0)); | |
971 | } | |
972 | ||
973 | *nr_written += nr_pages; | |
974 | start = cur_end + 1; | |
975 | } | |
976 | *page_started = 1; | |
977 | return 0; | |
978 | } | |
979 | ||
980 | static noinline int csum_exist_in_range(struct btrfs_root *root, | |
981 | u64 bytenr, u64 num_bytes) | |
982 | { | |
983 | int ret; | |
984 | struct btrfs_ordered_sum *sums; | |
985 | LIST_HEAD(list); | |
986 | ||
987 | ret = btrfs_lookup_csums_range(root->fs_info->csum_root, bytenr, | |
988 | bytenr + num_bytes - 1, &list); | |
989 | if (ret == 0 && list_empty(&list)) | |
990 | return 0; | |
991 | ||
992 | while (!list_empty(&list)) { | |
993 | sums = list_entry(list.next, struct btrfs_ordered_sum, list); | |
994 | list_del(&sums->list); | |
995 | kfree(sums); | |
996 | } | |
997 | return 1; | |
998 | } | |
999 | ||
1000 | /* | |
1001 | * when nowcow writeback call back. This checks for snapshots or COW copies | |
1002 | * of the extents that exist in the file, and COWs the file as required. | |
1003 | * | |
1004 | * If no cow copies or snapshots exist, we write directly to the existing | |
1005 | * blocks on disk | |
1006 | */ | |
1007 | static noinline int run_delalloc_nocow(struct inode *inode, | |
1008 | struct page *locked_page, | |
1009 | u64 start, u64 end, int *page_started, int force, | |
1010 | unsigned long *nr_written) | |
1011 | { | |
1012 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
1013 | struct btrfs_trans_handle *trans; | |
1014 | struct extent_buffer *leaf; | |
1015 | struct btrfs_path *path; | |
1016 | struct btrfs_file_extent_item *fi; | |
1017 | struct btrfs_key found_key; | |
1018 | u64 cow_start; | |
1019 | u64 cur_offset; | |
1020 | u64 extent_end; | |
1021 | u64 extent_offset; | |
1022 | u64 disk_bytenr; | |
1023 | u64 num_bytes; | |
1024 | int extent_type; | |
1025 | int ret; | |
1026 | int type; | |
1027 | int nocow; | |
1028 | int check_prev = 1; | |
1029 | bool nolock = false; | |
1030 | ||
1031 | path = btrfs_alloc_path(); | |
1032 | BUG_ON(!path); | |
1033 | if (root == root->fs_info->tree_root) { | |
1034 | nolock = true; | |
1035 | trans = btrfs_join_transaction_nolock(root, 1); | |
1036 | } else { | |
1037 | trans = btrfs_join_transaction(root, 1); | |
1038 | } | |
1039 | BUG_ON(!trans); | |
1040 | ||
1041 | cow_start = (u64)-1; | |
1042 | cur_offset = start; | |
1043 | while (1) { | |
1044 | ret = btrfs_lookup_file_extent(trans, root, path, inode->i_ino, | |
1045 | cur_offset, 0); | |
1046 | BUG_ON(ret < 0); | |
1047 | if (ret > 0 && path->slots[0] > 0 && check_prev) { | |
1048 | leaf = path->nodes[0]; | |
1049 | btrfs_item_key_to_cpu(leaf, &found_key, | |
1050 | path->slots[0] - 1); | |
1051 | if (found_key.objectid == inode->i_ino && | |
1052 | found_key.type == BTRFS_EXTENT_DATA_KEY) | |
1053 | path->slots[0]--; | |
1054 | } | |
1055 | check_prev = 0; | |
1056 | next_slot: | |
1057 | leaf = path->nodes[0]; | |
1058 | if (path->slots[0] >= btrfs_header_nritems(leaf)) { | |
1059 | ret = btrfs_next_leaf(root, path); | |
1060 | if (ret < 0) | |
1061 | BUG_ON(1); | |
1062 | if (ret > 0) | |
1063 | break; | |
1064 | leaf = path->nodes[0]; | |
1065 | } | |
1066 | ||
1067 | nocow = 0; | |
1068 | disk_bytenr = 0; | |
1069 | num_bytes = 0; | |
1070 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); | |
1071 | ||
1072 | if (found_key.objectid > inode->i_ino || | |
1073 | found_key.type > BTRFS_EXTENT_DATA_KEY || | |
1074 | found_key.offset > end) | |
1075 | break; | |
1076 | ||
1077 | if (found_key.offset > cur_offset) { | |
1078 | extent_end = found_key.offset; | |
1079 | extent_type = 0; | |
1080 | goto out_check; | |
1081 | } | |
1082 | ||
1083 | fi = btrfs_item_ptr(leaf, path->slots[0], | |
1084 | struct btrfs_file_extent_item); | |
1085 | extent_type = btrfs_file_extent_type(leaf, fi); | |
1086 | ||
1087 | if (extent_type == BTRFS_FILE_EXTENT_REG || | |
1088 | extent_type == BTRFS_FILE_EXTENT_PREALLOC) { | |
1089 | disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); | |
1090 | extent_offset = btrfs_file_extent_offset(leaf, fi); | |
1091 | extent_end = found_key.offset + | |
1092 | btrfs_file_extent_num_bytes(leaf, fi); | |
1093 | if (extent_end <= start) { | |
1094 | path->slots[0]++; | |
1095 | goto next_slot; | |
1096 | } | |
1097 | if (disk_bytenr == 0) | |
1098 | goto out_check; | |
1099 | if (btrfs_file_extent_compression(leaf, fi) || | |
1100 | btrfs_file_extent_encryption(leaf, fi) || | |
1101 | btrfs_file_extent_other_encoding(leaf, fi)) | |
1102 | goto out_check; | |
1103 | if (extent_type == BTRFS_FILE_EXTENT_REG && !force) | |
1104 | goto out_check; | |
1105 | if (btrfs_extent_readonly(root, disk_bytenr)) | |
1106 | goto out_check; | |
1107 | if (btrfs_cross_ref_exist(trans, root, inode->i_ino, | |
1108 | found_key.offset - | |
1109 | extent_offset, disk_bytenr)) | |
1110 | goto out_check; | |
1111 | disk_bytenr += extent_offset; | |
1112 | disk_bytenr += cur_offset - found_key.offset; | |
1113 | num_bytes = min(end + 1, extent_end) - cur_offset; | |
1114 | /* | |
1115 | * force cow if csum exists in the range. | |
1116 | * this ensure that csum for a given extent are | |
1117 | * either valid or do not exist. | |
1118 | */ | |
1119 | if (csum_exist_in_range(root, disk_bytenr, num_bytes)) | |
1120 | goto out_check; | |
1121 | nocow = 1; | |
1122 | } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) { | |
1123 | extent_end = found_key.offset + | |
1124 | btrfs_file_extent_inline_len(leaf, fi); | |
1125 | extent_end = ALIGN(extent_end, root->sectorsize); | |
1126 | } else { | |
1127 | BUG_ON(1); | |
1128 | } | |
1129 | out_check: | |
1130 | if (extent_end <= start) { | |
1131 | path->slots[0]++; | |
1132 | goto next_slot; | |
1133 | } | |
1134 | if (!nocow) { | |
1135 | if (cow_start == (u64)-1) | |
1136 | cow_start = cur_offset; | |
1137 | cur_offset = extent_end; | |
1138 | if (cur_offset > end) | |
1139 | break; | |
1140 | path->slots[0]++; | |
1141 | goto next_slot; | |
1142 | } | |
1143 | ||
1144 | btrfs_release_path(root, path); | |
1145 | if (cow_start != (u64)-1) { | |
1146 | ret = cow_file_range(inode, locked_page, cow_start, | |
1147 | found_key.offset - 1, page_started, | |
1148 | nr_written, 1); | |
1149 | BUG_ON(ret); | |
1150 | cow_start = (u64)-1; | |
1151 | } | |
1152 | ||
1153 | if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) { | |
1154 | struct extent_map *em; | |
1155 | struct extent_map_tree *em_tree; | |
1156 | em_tree = &BTRFS_I(inode)->extent_tree; | |
1157 | em = alloc_extent_map(GFP_NOFS); | |
1158 | em->start = cur_offset; | |
1159 | em->orig_start = em->start; | |
1160 | em->len = num_bytes; | |
1161 | em->block_len = num_bytes; | |
1162 | em->block_start = disk_bytenr; | |
1163 | em->bdev = root->fs_info->fs_devices->latest_bdev; | |
1164 | set_bit(EXTENT_FLAG_PINNED, &em->flags); | |
1165 | while (1) { | |
1166 | write_lock(&em_tree->lock); | |
1167 | ret = add_extent_mapping(em_tree, em); | |
1168 | write_unlock(&em_tree->lock); | |
1169 | if (ret != -EEXIST) { | |
1170 | free_extent_map(em); | |
1171 | break; | |
1172 | } | |
1173 | btrfs_drop_extent_cache(inode, em->start, | |
1174 | em->start + em->len - 1, 0); | |
1175 | } | |
1176 | type = BTRFS_ORDERED_PREALLOC; | |
1177 | } else { | |
1178 | type = BTRFS_ORDERED_NOCOW; | |
1179 | } | |
1180 | ||
1181 | ret = btrfs_add_ordered_extent(inode, cur_offset, disk_bytenr, | |
1182 | num_bytes, num_bytes, type); | |
1183 | BUG_ON(ret); | |
1184 | ||
1185 | if (root->root_key.objectid == | |
1186 | BTRFS_DATA_RELOC_TREE_OBJECTID) { | |
1187 | ret = btrfs_reloc_clone_csums(inode, cur_offset, | |
1188 | num_bytes); | |
1189 | BUG_ON(ret); | |
1190 | } | |
1191 | ||
1192 | extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree, | |
1193 | cur_offset, cur_offset + num_bytes - 1, | |
1194 | locked_page, EXTENT_CLEAR_UNLOCK_PAGE | | |
1195 | EXTENT_CLEAR_UNLOCK | EXTENT_CLEAR_DELALLOC | | |
1196 | EXTENT_SET_PRIVATE2); | |
1197 | cur_offset = extent_end; | |
1198 | if (cur_offset > end) | |
1199 | break; | |
1200 | } | |
1201 | btrfs_release_path(root, path); | |
1202 | ||
1203 | if (cur_offset <= end && cow_start == (u64)-1) | |
1204 | cow_start = cur_offset; | |
1205 | if (cow_start != (u64)-1) { | |
1206 | ret = cow_file_range(inode, locked_page, cow_start, end, | |
1207 | page_started, nr_written, 1); | |
1208 | BUG_ON(ret); | |
1209 | } | |
1210 | ||
1211 | if (nolock) { | |
1212 | ret = btrfs_end_transaction_nolock(trans, root); | |
1213 | BUG_ON(ret); | |
1214 | } else { | |
1215 | ret = btrfs_end_transaction(trans, root); | |
1216 | BUG_ON(ret); | |
1217 | } | |
1218 | btrfs_free_path(path); | |
1219 | return 0; | |
1220 | } | |
1221 | ||
1222 | /* | |
1223 | * extent_io.c call back to do delayed allocation processing | |
1224 | */ | |
1225 | static int run_delalloc_range(struct inode *inode, struct page *locked_page, | |
1226 | u64 start, u64 end, int *page_started, | |
1227 | unsigned long *nr_written) | |
1228 | { | |
1229 | int ret; | |
1230 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
1231 | ||
1232 | if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) | |
1233 | ret = run_delalloc_nocow(inode, locked_page, start, end, | |
1234 | page_started, 1, nr_written); | |
1235 | else if (BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC) | |
1236 | ret = run_delalloc_nocow(inode, locked_page, start, end, | |
1237 | page_started, 0, nr_written); | |
1238 | else if (!btrfs_test_opt(root, COMPRESS) && | |
1239 | !(BTRFS_I(inode)->force_compress)) | |
1240 | ret = cow_file_range(inode, locked_page, start, end, | |
1241 | page_started, nr_written, 1); | |
1242 | else | |
1243 | ret = cow_file_range_async(inode, locked_page, start, end, | |
1244 | page_started, nr_written); | |
1245 | return ret; | |
1246 | } | |
1247 | ||
1248 | static int btrfs_split_extent_hook(struct inode *inode, | |
1249 | struct extent_state *orig, u64 split) | |
1250 | { | |
1251 | /* not delalloc, ignore it */ | |
1252 | if (!(orig->state & EXTENT_DELALLOC)) | |
1253 | return 0; | |
1254 | ||
1255 | atomic_inc(&BTRFS_I(inode)->outstanding_extents); | |
1256 | return 0; | |
1257 | } | |
1258 | ||
1259 | /* | |
1260 | * extent_io.c merge_extent_hook, used to track merged delayed allocation | |
1261 | * extents so we can keep track of new extents that are just merged onto old | |
1262 | * extents, such as when we are doing sequential writes, so we can properly | |
1263 | * account for the metadata space we'll need. | |
1264 | */ | |
1265 | static int btrfs_merge_extent_hook(struct inode *inode, | |
1266 | struct extent_state *new, | |
1267 | struct extent_state *other) | |
1268 | { | |
1269 | /* not delalloc, ignore it */ | |
1270 | if (!(other->state & EXTENT_DELALLOC)) | |
1271 | return 0; | |
1272 | ||
1273 | atomic_dec(&BTRFS_I(inode)->outstanding_extents); | |
1274 | return 0; | |
1275 | } | |
1276 | ||
1277 | /* | |
1278 | * extent_io.c set_bit_hook, used to track delayed allocation | |
1279 | * bytes in this file, and to maintain the list of inodes that | |
1280 | * have pending delalloc work to be done. | |
1281 | */ | |
1282 | static int btrfs_set_bit_hook(struct inode *inode, | |
1283 | struct extent_state *state, int *bits) | |
1284 | { | |
1285 | ||
1286 | /* | |
1287 | * set_bit and clear bit hooks normally require _irqsave/restore | |
1288 | * but in this case, we are only testeing for the DELALLOC | |
1289 | * bit, which is only set or cleared with irqs on | |
1290 | */ | |
1291 | if (!(state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) { | |
1292 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
1293 | u64 len = state->end + 1 - state->start; | |
1294 | int do_list = (root->root_key.objectid != | |
1295 | BTRFS_ROOT_TREE_OBJECTID); | |
1296 | ||
1297 | if (*bits & EXTENT_FIRST_DELALLOC) | |
1298 | *bits &= ~EXTENT_FIRST_DELALLOC; | |
1299 | else | |
1300 | atomic_inc(&BTRFS_I(inode)->outstanding_extents); | |
1301 | ||
1302 | spin_lock(&root->fs_info->delalloc_lock); | |
1303 | BTRFS_I(inode)->delalloc_bytes += len; | |
1304 | root->fs_info->delalloc_bytes += len; | |
1305 | if (do_list && list_empty(&BTRFS_I(inode)->delalloc_inodes)) { | |
1306 | list_add_tail(&BTRFS_I(inode)->delalloc_inodes, | |
1307 | &root->fs_info->delalloc_inodes); | |
1308 | } | |
1309 | spin_unlock(&root->fs_info->delalloc_lock); | |
1310 | } | |
1311 | return 0; | |
1312 | } | |
1313 | ||
1314 | /* | |
1315 | * extent_io.c clear_bit_hook, see set_bit_hook for why | |
1316 | */ | |
1317 | static int btrfs_clear_bit_hook(struct inode *inode, | |
1318 | struct extent_state *state, int *bits) | |
1319 | { | |
1320 | /* | |
1321 | * set_bit and clear bit hooks normally require _irqsave/restore | |
1322 | * but in this case, we are only testeing for the DELALLOC | |
1323 | * bit, which is only set or cleared with irqs on | |
1324 | */ | |
1325 | if ((state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) { | |
1326 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
1327 | u64 len = state->end + 1 - state->start; | |
1328 | int do_list = (root->root_key.objectid != | |
1329 | BTRFS_ROOT_TREE_OBJECTID); | |
1330 | ||
1331 | if (*bits & EXTENT_FIRST_DELALLOC) | |
1332 | *bits &= ~EXTENT_FIRST_DELALLOC; | |
1333 | else if (!(*bits & EXTENT_DO_ACCOUNTING)) | |
1334 | atomic_dec(&BTRFS_I(inode)->outstanding_extents); | |
1335 | ||
1336 | if (*bits & EXTENT_DO_ACCOUNTING) | |
1337 | btrfs_delalloc_release_metadata(inode, len); | |
1338 | ||
1339 | if (root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID | |
1340 | && do_list) | |
1341 | btrfs_free_reserved_data_space(inode, len); | |
1342 | ||
1343 | spin_lock(&root->fs_info->delalloc_lock); | |
1344 | root->fs_info->delalloc_bytes -= len; | |
1345 | BTRFS_I(inode)->delalloc_bytes -= len; | |
1346 | ||
1347 | if (do_list && BTRFS_I(inode)->delalloc_bytes == 0 && | |
1348 | !list_empty(&BTRFS_I(inode)->delalloc_inodes)) { | |
1349 | list_del_init(&BTRFS_I(inode)->delalloc_inodes); | |
1350 | } | |
1351 | spin_unlock(&root->fs_info->delalloc_lock); | |
1352 | } | |
1353 | return 0; | |
1354 | } | |
1355 | ||
1356 | /* | |
1357 | * extent_io.c merge_bio_hook, this must check the chunk tree to make sure | |
1358 | * we don't create bios that span stripes or chunks | |
1359 | */ | |
1360 | int btrfs_merge_bio_hook(struct page *page, unsigned long offset, | |
1361 | size_t size, struct bio *bio, | |
1362 | unsigned long bio_flags) | |
1363 | { | |
1364 | struct btrfs_root *root = BTRFS_I(page->mapping->host)->root; | |
1365 | struct btrfs_mapping_tree *map_tree; | |
1366 | u64 logical = (u64)bio->bi_sector << 9; | |
1367 | u64 length = 0; | |
1368 | u64 map_length; | |
1369 | int ret; | |
1370 | ||
1371 | if (bio_flags & EXTENT_BIO_COMPRESSED) | |
1372 | return 0; | |
1373 | ||
1374 | length = bio->bi_size; | |
1375 | map_tree = &root->fs_info->mapping_tree; | |
1376 | map_length = length; | |
1377 | ret = btrfs_map_block(map_tree, READ, logical, | |
1378 | &map_length, NULL, 0); | |
1379 | ||
1380 | if (map_length < length + size) | |
1381 | return 1; | |
1382 | return ret; | |
1383 | } | |
1384 | ||
1385 | /* | |
1386 | * in order to insert checksums into the metadata in large chunks, | |
1387 | * we wait until bio submission time. All the pages in the bio are | |
1388 | * checksummed and sums are attached onto the ordered extent record. | |
1389 | * | |
1390 | * At IO completion time the cums attached on the ordered extent record | |
1391 | * are inserted into the btree | |
1392 | */ | |
1393 | static int __btrfs_submit_bio_start(struct inode *inode, int rw, | |
1394 | struct bio *bio, int mirror_num, | |
1395 | unsigned long bio_flags, | |
1396 | u64 bio_offset) | |
1397 | { | |
1398 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
1399 | int ret = 0; | |
1400 | ||
1401 | ret = btrfs_csum_one_bio(root, inode, bio, 0, 0); | |
1402 | BUG_ON(ret); | |
1403 | return 0; | |
1404 | } | |
1405 | ||
1406 | /* | |
1407 | * in order to insert checksums into the metadata in large chunks, | |
1408 | * we wait until bio submission time. All the pages in the bio are | |
1409 | * checksummed and sums are attached onto the ordered extent record. | |
1410 | * | |
1411 | * At IO completion time the cums attached on the ordered extent record | |
1412 | * are inserted into the btree | |
1413 | */ | |
1414 | static int __btrfs_submit_bio_done(struct inode *inode, int rw, struct bio *bio, | |
1415 | int mirror_num, unsigned long bio_flags, | |
1416 | u64 bio_offset) | |
1417 | { | |
1418 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
1419 | return btrfs_map_bio(root, rw, bio, mirror_num, 1); | |
1420 | } | |
1421 | ||
1422 | /* | |
1423 | * extent_io.c submission hook. This does the right thing for csum calculation | |
1424 | * on write, or reading the csums from the tree before a read | |
1425 | */ | |
1426 | static int btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio, | |
1427 | int mirror_num, unsigned long bio_flags, | |
1428 | u64 bio_offset) | |
1429 | { | |
1430 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
1431 | int ret = 0; | |
1432 | int skip_sum; | |
1433 | ||
1434 | skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM; | |
1435 | ||
1436 | if (root == root->fs_info->tree_root) | |
1437 | ret = btrfs_bio_wq_end_io(root->fs_info, bio, 2); | |
1438 | else | |
1439 | ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0); | |
1440 | BUG_ON(ret); | |
1441 | ||
1442 | if (!(rw & REQ_WRITE)) { | |
1443 | if (bio_flags & EXTENT_BIO_COMPRESSED) { | |
1444 | return btrfs_submit_compressed_read(inode, bio, | |
1445 | mirror_num, bio_flags); | |
1446 | } else if (!skip_sum) | |
1447 | btrfs_lookup_bio_sums(root, inode, bio, NULL); | |
1448 | goto mapit; | |
1449 | } else if (!skip_sum) { | |
1450 | /* csum items have already been cloned */ | |
1451 | if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID) | |
1452 | goto mapit; | |
1453 | /* we're doing a write, do the async checksumming */ | |
1454 | return btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info, | |
1455 | inode, rw, bio, mirror_num, | |
1456 | bio_flags, bio_offset, | |
1457 | __btrfs_submit_bio_start, | |
1458 | __btrfs_submit_bio_done); | |
1459 | } | |
1460 | ||
1461 | mapit: | |
1462 | return btrfs_map_bio(root, rw, bio, mirror_num, 0); | |
1463 | } | |
1464 | ||
1465 | /* | |
1466 | * given a list of ordered sums record them in the inode. This happens | |
1467 | * at IO completion time based on sums calculated at bio submission time. | |
1468 | */ | |
1469 | static noinline int add_pending_csums(struct btrfs_trans_handle *trans, | |
1470 | struct inode *inode, u64 file_offset, | |
1471 | struct list_head *list) | |
1472 | { | |
1473 | struct btrfs_ordered_sum *sum; | |
1474 | ||
1475 | btrfs_set_trans_block_group(trans, inode); | |
1476 | ||
1477 | list_for_each_entry(sum, list, list) { | |
1478 | btrfs_csum_file_blocks(trans, | |
1479 | BTRFS_I(inode)->root->fs_info->csum_root, sum); | |
1480 | } | |
1481 | return 0; | |
1482 | } | |
1483 | ||
1484 | int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end, | |
1485 | struct extent_state **cached_state) | |
1486 | { | |
1487 | if ((end & (PAGE_CACHE_SIZE - 1)) == 0) | |
1488 | WARN_ON(1); | |
1489 | return set_extent_delalloc(&BTRFS_I(inode)->io_tree, start, end, | |
1490 | cached_state, GFP_NOFS); | |
1491 | } | |
1492 | ||
1493 | /* see btrfs_writepage_start_hook for details on why this is required */ | |
1494 | struct btrfs_writepage_fixup { | |
1495 | struct page *page; | |
1496 | struct btrfs_work work; | |
1497 | }; | |
1498 | ||
1499 | static void btrfs_writepage_fixup_worker(struct btrfs_work *work) | |
1500 | { | |
1501 | struct btrfs_writepage_fixup *fixup; | |
1502 | struct btrfs_ordered_extent *ordered; | |
1503 | struct extent_state *cached_state = NULL; | |
1504 | struct page *page; | |
1505 | struct inode *inode; | |
1506 | u64 page_start; | |
1507 | u64 page_end; | |
1508 | ||
1509 | fixup = container_of(work, struct btrfs_writepage_fixup, work); | |
1510 | page = fixup->page; | |
1511 | again: | |
1512 | lock_page(page); | |
1513 | if (!page->mapping || !PageDirty(page) || !PageChecked(page)) { | |
1514 | ClearPageChecked(page); | |
1515 | goto out_page; | |
1516 | } | |
1517 | ||
1518 | inode = page->mapping->host; | |
1519 | page_start = page_offset(page); | |
1520 | page_end = page_offset(page) + PAGE_CACHE_SIZE - 1; | |
1521 | ||
1522 | lock_extent_bits(&BTRFS_I(inode)->io_tree, page_start, page_end, 0, | |
1523 | &cached_state, GFP_NOFS); | |
1524 | ||
1525 | /* already ordered? We're done */ | |
1526 | if (PagePrivate2(page)) | |
1527 | goto out; | |
1528 | ||
1529 | ordered = btrfs_lookup_ordered_extent(inode, page_start); | |
1530 | if (ordered) { | |
1531 | unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, | |
1532 | page_end, &cached_state, GFP_NOFS); | |
1533 | unlock_page(page); | |
1534 | btrfs_start_ordered_extent(inode, ordered, 1); | |
1535 | goto again; | |
1536 | } | |
1537 | ||
1538 | BUG(); | |
1539 | btrfs_set_extent_delalloc(inode, page_start, page_end, &cached_state); | |
1540 | ClearPageChecked(page); | |
1541 | out: | |
1542 | unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, page_end, | |
1543 | &cached_state, GFP_NOFS); | |
1544 | out_page: | |
1545 | unlock_page(page); | |
1546 | page_cache_release(page); | |
1547 | } | |
1548 | ||
1549 | /* | |
1550 | * There are a few paths in the higher layers of the kernel that directly | |
1551 | * set the page dirty bit without asking the filesystem if it is a | |
1552 | * good idea. This causes problems because we want to make sure COW | |
1553 | * properly happens and the data=ordered rules are followed. | |
1554 | * | |
1555 | * In our case any range that doesn't have the ORDERED bit set | |
1556 | * hasn't been properly setup for IO. We kick off an async process | |
1557 | * to fix it up. The async helper will wait for ordered extents, set | |
1558 | * the delalloc bit and make it safe to write the page. | |
1559 | */ | |
1560 | static int btrfs_writepage_start_hook(struct page *page, u64 start, u64 end) | |
1561 | { | |
1562 | struct inode *inode = page->mapping->host; | |
1563 | struct btrfs_writepage_fixup *fixup; | |
1564 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
1565 | ||
1566 | /* this page is properly in the ordered list */ | |
1567 | if (TestClearPagePrivate2(page)) | |
1568 | return 0; | |
1569 | ||
1570 | if (PageChecked(page)) | |
1571 | return -EAGAIN; | |
1572 | ||
1573 | fixup = kzalloc(sizeof(*fixup), GFP_NOFS); | |
1574 | if (!fixup) | |
1575 | return -EAGAIN; | |
1576 | ||
1577 | SetPageChecked(page); | |
1578 | page_cache_get(page); | |
1579 | fixup->work.func = btrfs_writepage_fixup_worker; | |
1580 | fixup->page = page; | |
1581 | btrfs_queue_worker(&root->fs_info->fixup_workers, &fixup->work); | |
1582 | return -EAGAIN; | |
1583 | } | |
1584 | ||
1585 | static int insert_reserved_file_extent(struct btrfs_trans_handle *trans, | |
1586 | struct inode *inode, u64 file_pos, | |
1587 | u64 disk_bytenr, u64 disk_num_bytes, | |
1588 | u64 num_bytes, u64 ram_bytes, | |
1589 | u8 compression, u8 encryption, | |
1590 | u16 other_encoding, int extent_type) | |
1591 | { | |
1592 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
1593 | struct btrfs_file_extent_item *fi; | |
1594 | struct btrfs_path *path; | |
1595 | struct extent_buffer *leaf; | |
1596 | struct btrfs_key ins; | |
1597 | u64 hint; | |
1598 | int ret; | |
1599 | ||
1600 | path = btrfs_alloc_path(); | |
1601 | BUG_ON(!path); | |
1602 | ||
1603 | path->leave_spinning = 1; | |
1604 | ||
1605 | /* | |
1606 | * we may be replacing one extent in the tree with another. | |
1607 | * The new extent is pinned in the extent map, and we don't want | |
1608 | * to drop it from the cache until it is completely in the btree. | |
1609 | * | |
1610 | * So, tell btrfs_drop_extents to leave this extent in the cache. | |
1611 | * the caller is expected to unpin it and allow it to be merged | |
1612 | * with the others. | |
1613 | */ | |
1614 | ret = btrfs_drop_extents(trans, inode, file_pos, file_pos + num_bytes, | |
1615 | &hint, 0); | |
1616 | BUG_ON(ret); | |
1617 | ||
1618 | ins.objectid = inode->i_ino; | |
1619 | ins.offset = file_pos; | |
1620 | ins.type = BTRFS_EXTENT_DATA_KEY; | |
1621 | ret = btrfs_insert_empty_item(trans, root, path, &ins, sizeof(*fi)); | |
1622 | BUG_ON(ret); | |
1623 | leaf = path->nodes[0]; | |
1624 | fi = btrfs_item_ptr(leaf, path->slots[0], | |
1625 | struct btrfs_file_extent_item); | |
1626 | btrfs_set_file_extent_generation(leaf, fi, trans->transid); | |
1627 | btrfs_set_file_extent_type(leaf, fi, extent_type); | |
1628 | btrfs_set_file_extent_disk_bytenr(leaf, fi, disk_bytenr); | |
1629 | btrfs_set_file_extent_disk_num_bytes(leaf, fi, disk_num_bytes); | |
1630 | btrfs_set_file_extent_offset(leaf, fi, 0); | |
1631 | btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes); | |
1632 | btrfs_set_file_extent_ram_bytes(leaf, fi, ram_bytes); | |
1633 | btrfs_set_file_extent_compression(leaf, fi, compression); | |
1634 | btrfs_set_file_extent_encryption(leaf, fi, encryption); | |
1635 | btrfs_set_file_extent_other_encoding(leaf, fi, other_encoding); | |
1636 | ||
1637 | btrfs_unlock_up_safe(path, 1); | |
1638 | btrfs_set_lock_blocking(leaf); | |
1639 | ||
1640 | btrfs_mark_buffer_dirty(leaf); | |
1641 | ||
1642 | inode_add_bytes(inode, num_bytes); | |
1643 | ||
1644 | ins.objectid = disk_bytenr; | |
1645 | ins.offset = disk_num_bytes; | |
1646 | ins.type = BTRFS_EXTENT_ITEM_KEY; | |
1647 | ret = btrfs_alloc_reserved_file_extent(trans, root, | |
1648 | root->root_key.objectid, | |
1649 | inode->i_ino, file_pos, &ins); | |
1650 | BUG_ON(ret); | |
1651 | btrfs_free_path(path); | |
1652 | ||
1653 | return 0; | |
1654 | } | |
1655 | ||
1656 | /* | |
1657 | * helper function for btrfs_finish_ordered_io, this | |
1658 | * just reads in some of the csum leaves to prime them into ram | |
1659 | * before we start the transaction. It limits the amount of btree | |
1660 | * reads required while inside the transaction. | |
1661 | */ | |
1662 | /* as ordered data IO finishes, this gets called so we can finish | |
1663 | * an ordered extent if the range of bytes in the file it covers are | |
1664 | * fully written. | |
1665 | */ | |
1666 | static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end) | |
1667 | { | |
1668 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
1669 | struct btrfs_trans_handle *trans = NULL; | |
1670 | struct btrfs_ordered_extent *ordered_extent = NULL; | |
1671 | struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; | |
1672 | struct extent_state *cached_state = NULL; | |
1673 | int compressed = 0; | |
1674 | int ret; | |
1675 | bool nolock = false; | |
1676 | ||
1677 | ret = btrfs_dec_test_ordered_pending(inode, &ordered_extent, start, | |
1678 | end - start + 1); | |
1679 | if (!ret) | |
1680 | return 0; | |
1681 | BUG_ON(!ordered_extent); | |
1682 | ||
1683 | nolock = (root == root->fs_info->tree_root); | |
1684 | ||
1685 | if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags)) { | |
1686 | BUG_ON(!list_empty(&ordered_extent->list)); | |
1687 | ret = btrfs_ordered_update_i_size(inode, 0, ordered_extent); | |
1688 | if (!ret) { | |
1689 | if (nolock) | |
1690 | trans = btrfs_join_transaction_nolock(root, 1); | |
1691 | else | |
1692 | trans = btrfs_join_transaction(root, 1); | |
1693 | BUG_ON(!trans); | |
1694 | btrfs_set_trans_block_group(trans, inode); | |
1695 | trans->block_rsv = &root->fs_info->delalloc_block_rsv; | |
1696 | ret = btrfs_update_inode(trans, root, inode); | |
1697 | BUG_ON(ret); | |
1698 | } | |
1699 | goto out; | |
1700 | } | |
1701 | ||
1702 | lock_extent_bits(io_tree, ordered_extent->file_offset, | |
1703 | ordered_extent->file_offset + ordered_extent->len - 1, | |
1704 | 0, &cached_state, GFP_NOFS); | |
1705 | ||
1706 | if (nolock) | |
1707 | trans = btrfs_join_transaction_nolock(root, 1); | |
1708 | else | |
1709 | trans = btrfs_join_transaction(root, 1); | |
1710 | btrfs_set_trans_block_group(trans, inode); | |
1711 | trans->block_rsv = &root->fs_info->delalloc_block_rsv; | |
1712 | ||
1713 | if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered_extent->flags)) | |
1714 | compressed = 1; | |
1715 | if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) { | |
1716 | BUG_ON(compressed); | |
1717 | ret = btrfs_mark_extent_written(trans, inode, | |
1718 | ordered_extent->file_offset, | |
1719 | ordered_extent->file_offset + | |
1720 | ordered_extent->len); | |
1721 | BUG_ON(ret); | |
1722 | } else { | |
1723 | BUG_ON(root == root->fs_info->tree_root); | |
1724 | ret = insert_reserved_file_extent(trans, inode, | |
1725 | ordered_extent->file_offset, | |
1726 | ordered_extent->start, | |
1727 | ordered_extent->disk_len, | |
1728 | ordered_extent->len, | |
1729 | ordered_extent->len, | |
1730 | compressed, 0, 0, | |
1731 | BTRFS_FILE_EXTENT_REG); | |
1732 | unpin_extent_cache(&BTRFS_I(inode)->extent_tree, | |
1733 | ordered_extent->file_offset, | |
1734 | ordered_extent->len); | |
1735 | BUG_ON(ret); | |
1736 | } | |
1737 | unlock_extent_cached(io_tree, ordered_extent->file_offset, | |
1738 | ordered_extent->file_offset + | |
1739 | ordered_extent->len - 1, &cached_state, GFP_NOFS); | |
1740 | ||
1741 | add_pending_csums(trans, inode, ordered_extent->file_offset, | |
1742 | &ordered_extent->list); | |
1743 | ||
1744 | btrfs_ordered_update_i_size(inode, 0, ordered_extent); | |
1745 | ret = btrfs_update_inode(trans, root, inode); | |
1746 | BUG_ON(ret); | |
1747 | out: | |
1748 | if (nolock) { | |
1749 | if (trans) | |
1750 | btrfs_end_transaction_nolock(trans, root); | |
1751 | } else { | |
1752 | btrfs_delalloc_release_metadata(inode, ordered_extent->len); | |
1753 | if (trans) | |
1754 | btrfs_end_transaction(trans, root); | |
1755 | } | |
1756 | ||
1757 | /* once for us */ | |
1758 | btrfs_put_ordered_extent(ordered_extent); | |
1759 | /* once for the tree */ | |
1760 | btrfs_put_ordered_extent(ordered_extent); | |
1761 | ||
1762 | return 0; | |
1763 | } | |
1764 | ||
1765 | static int btrfs_writepage_end_io_hook(struct page *page, u64 start, u64 end, | |
1766 | struct extent_state *state, int uptodate) | |
1767 | { | |
1768 | ClearPagePrivate2(page); | |
1769 | return btrfs_finish_ordered_io(page->mapping->host, start, end); | |
1770 | } | |
1771 | ||
1772 | /* | |
1773 | * When IO fails, either with EIO or csum verification fails, we | |
1774 | * try other mirrors that might have a good copy of the data. This | |
1775 | * io_failure_record is used to record state as we go through all the | |
1776 | * mirrors. If another mirror has good data, the page is set up to date | |
1777 | * and things continue. If a good mirror can't be found, the original | |
1778 | * bio end_io callback is called to indicate things have failed. | |
1779 | */ | |
1780 | struct io_failure_record { | |
1781 | struct page *page; | |
1782 | u64 start; | |
1783 | u64 len; | |
1784 | u64 logical; | |
1785 | unsigned long bio_flags; | |
1786 | int last_mirror; | |
1787 | }; | |
1788 | ||
1789 | static int btrfs_io_failed_hook(struct bio *failed_bio, | |
1790 | struct page *page, u64 start, u64 end, | |
1791 | struct extent_state *state) | |
1792 | { | |
1793 | struct io_failure_record *failrec = NULL; | |
1794 | u64 private; | |
1795 | struct extent_map *em; | |
1796 | struct inode *inode = page->mapping->host; | |
1797 | struct extent_io_tree *failure_tree = &BTRFS_I(inode)->io_failure_tree; | |
1798 | struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; | |
1799 | struct bio *bio; | |
1800 | int num_copies; | |
1801 | int ret; | |
1802 | int rw; | |
1803 | u64 logical; | |
1804 | ||
1805 | ret = get_state_private(failure_tree, start, &private); | |
1806 | if (ret) { | |
1807 | failrec = kmalloc(sizeof(*failrec), GFP_NOFS); | |
1808 | if (!failrec) | |
1809 | return -ENOMEM; | |
1810 | failrec->start = start; | |
1811 | failrec->len = end - start + 1; | |
1812 | failrec->last_mirror = 0; | |
1813 | failrec->bio_flags = 0; | |
1814 | ||
1815 | read_lock(&em_tree->lock); | |
1816 | em = lookup_extent_mapping(em_tree, start, failrec->len); | |
1817 | if (em->start > start || em->start + em->len < start) { | |
1818 | free_extent_map(em); | |
1819 | em = NULL; | |
1820 | } | |
1821 | read_unlock(&em_tree->lock); | |
1822 | ||
1823 | if (!em || IS_ERR(em)) { | |
1824 | kfree(failrec); | |
1825 | return -EIO; | |
1826 | } | |
1827 | logical = start - em->start; | |
1828 | logical = em->block_start + logical; | |
1829 | if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) { | |
1830 | logical = em->block_start; | |
1831 | failrec->bio_flags = EXTENT_BIO_COMPRESSED; | |
1832 | } | |
1833 | failrec->logical = logical; | |
1834 | free_extent_map(em); | |
1835 | set_extent_bits(failure_tree, start, end, EXTENT_LOCKED | | |
1836 | EXTENT_DIRTY, GFP_NOFS); | |
1837 | set_state_private(failure_tree, start, | |
1838 | (u64)(unsigned long)failrec); | |
1839 | } else { | |
1840 | failrec = (struct io_failure_record *)(unsigned long)private; | |
1841 | } | |
1842 | num_copies = btrfs_num_copies( | |
1843 | &BTRFS_I(inode)->root->fs_info->mapping_tree, | |
1844 | failrec->logical, failrec->len); | |
1845 | failrec->last_mirror++; | |
1846 | if (!state) { | |
1847 | spin_lock(&BTRFS_I(inode)->io_tree.lock); | |
1848 | state = find_first_extent_bit_state(&BTRFS_I(inode)->io_tree, | |
1849 | failrec->start, | |
1850 | EXTENT_LOCKED); | |
1851 | if (state && state->start != failrec->start) | |
1852 | state = NULL; | |
1853 | spin_unlock(&BTRFS_I(inode)->io_tree.lock); | |
1854 | } | |
1855 | if (!state || failrec->last_mirror > num_copies) { | |
1856 | set_state_private(failure_tree, failrec->start, 0); | |
1857 | clear_extent_bits(failure_tree, failrec->start, | |
1858 | failrec->start + failrec->len - 1, | |
1859 | EXTENT_LOCKED | EXTENT_DIRTY, GFP_NOFS); | |
1860 | kfree(failrec); | |
1861 | return -EIO; | |
1862 | } | |
1863 | bio = bio_alloc(GFP_NOFS, 1); | |
1864 | bio->bi_private = state; | |
1865 | bio->bi_end_io = failed_bio->bi_end_io; | |
1866 | bio->bi_sector = failrec->logical >> 9; | |
1867 | bio->bi_bdev = failed_bio->bi_bdev; | |
1868 | bio->bi_size = 0; | |
1869 | ||
1870 | bio_add_page(bio, page, failrec->len, start - page_offset(page)); | |
1871 | if (failed_bio->bi_rw & REQ_WRITE) | |
1872 | rw = WRITE; | |
1873 | else | |
1874 | rw = READ; | |
1875 | ||
1876 | BTRFS_I(inode)->io_tree.ops->submit_bio_hook(inode, rw, bio, | |
1877 | failrec->last_mirror, | |
1878 | failrec->bio_flags, 0); | |
1879 | return 0; | |
1880 | } | |
1881 | ||
1882 | /* | |
1883 | * each time an IO finishes, we do a fast check in the IO failure tree | |
1884 | * to see if we need to process or clean up an io_failure_record | |
1885 | */ | |
1886 | static int btrfs_clean_io_failures(struct inode *inode, u64 start) | |
1887 | { | |
1888 | u64 private; | |
1889 | u64 private_failure; | |
1890 | struct io_failure_record *failure; | |
1891 | int ret; | |
1892 | ||
1893 | private = 0; | |
1894 | if (count_range_bits(&BTRFS_I(inode)->io_failure_tree, &private, | |
1895 | (u64)-1, 1, EXTENT_DIRTY)) { | |
1896 | ret = get_state_private(&BTRFS_I(inode)->io_failure_tree, | |
1897 | start, &private_failure); | |
1898 | if (ret == 0) { | |
1899 | failure = (struct io_failure_record *)(unsigned long) | |
1900 | private_failure; | |
1901 | set_state_private(&BTRFS_I(inode)->io_failure_tree, | |
1902 | failure->start, 0); | |
1903 | clear_extent_bits(&BTRFS_I(inode)->io_failure_tree, | |
1904 | failure->start, | |
1905 | failure->start + failure->len - 1, | |
1906 | EXTENT_DIRTY | EXTENT_LOCKED, | |
1907 | GFP_NOFS); | |
1908 | kfree(failure); | |
1909 | } | |
1910 | } | |
1911 | return 0; | |
1912 | } | |
1913 | ||
1914 | /* | |
1915 | * when reads are done, we need to check csums to verify the data is correct | |
1916 | * if there's a match, we allow the bio to finish. If not, we go through | |
1917 | * the io_failure_record routines to find good copies | |
1918 | */ | |
1919 | static int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end, | |
1920 | struct extent_state *state) | |
1921 | { | |
1922 | size_t offset = start - ((u64)page->index << PAGE_CACHE_SHIFT); | |
1923 | struct inode *inode = page->mapping->host; | |
1924 | struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; | |
1925 | char *kaddr; | |
1926 | u64 private = ~(u32)0; | |
1927 | int ret; | |
1928 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
1929 | u32 csum = ~(u32)0; | |
1930 | ||
1931 | if (PageChecked(page)) { | |
1932 | ClearPageChecked(page); | |
1933 | goto good; | |
1934 | } | |
1935 | ||
1936 | if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM) | |
1937 | return 0; | |
1938 | ||
1939 | if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID && | |
1940 | test_range_bit(io_tree, start, end, EXTENT_NODATASUM, 1, NULL)) { | |
1941 | clear_extent_bits(io_tree, start, end, EXTENT_NODATASUM, | |
1942 | GFP_NOFS); | |
1943 | return 0; | |
1944 | } | |
1945 | ||
1946 | if (state && state->start == start) { | |
1947 | private = state->private; | |
1948 | ret = 0; | |
1949 | } else { | |
1950 | ret = get_state_private(io_tree, start, &private); | |
1951 | } | |
1952 | kaddr = kmap_atomic(page, KM_USER0); | |
1953 | if (ret) | |
1954 | goto zeroit; | |
1955 | ||
1956 | csum = btrfs_csum_data(root, kaddr + offset, csum, end - start + 1); | |
1957 | btrfs_csum_final(csum, (char *)&csum); | |
1958 | if (csum != private) | |
1959 | goto zeroit; | |
1960 | ||
1961 | kunmap_atomic(kaddr, KM_USER0); | |
1962 | good: | |
1963 | /* if the io failure tree for this inode is non-empty, | |
1964 | * check to see if we've recovered from a failed IO | |
1965 | */ | |
1966 | btrfs_clean_io_failures(inode, start); | |
1967 | return 0; | |
1968 | ||
1969 | zeroit: | |
1970 | if (printk_ratelimit()) { | |
1971 | printk(KERN_INFO "btrfs csum failed ino %lu off %llu csum %u " | |
1972 | "private %llu\n", page->mapping->host->i_ino, | |
1973 | (unsigned long long)start, csum, | |
1974 | (unsigned long long)private); | |
1975 | } | |
1976 | memset(kaddr + offset, 1, end - start + 1); | |
1977 | flush_dcache_page(page); | |
1978 | kunmap_atomic(kaddr, KM_USER0); | |
1979 | if (private == 0) | |
1980 | return 0; | |
1981 | return -EIO; | |
1982 | } | |
1983 | ||
1984 | struct delayed_iput { | |
1985 | struct list_head list; | |
1986 | struct inode *inode; | |
1987 | }; | |
1988 | ||
1989 | void btrfs_add_delayed_iput(struct inode *inode) | |
1990 | { | |
1991 | struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info; | |
1992 | struct delayed_iput *delayed; | |
1993 | ||
1994 | if (atomic_add_unless(&inode->i_count, -1, 1)) | |
1995 | return; | |
1996 | ||
1997 | delayed = kmalloc(sizeof(*delayed), GFP_NOFS | __GFP_NOFAIL); | |
1998 | delayed->inode = inode; | |
1999 | ||
2000 | spin_lock(&fs_info->delayed_iput_lock); | |
2001 | list_add_tail(&delayed->list, &fs_info->delayed_iputs); | |
2002 | spin_unlock(&fs_info->delayed_iput_lock); | |
2003 | } | |
2004 | ||
2005 | void btrfs_run_delayed_iputs(struct btrfs_root *root) | |
2006 | { | |
2007 | LIST_HEAD(list); | |
2008 | struct btrfs_fs_info *fs_info = root->fs_info; | |
2009 | struct delayed_iput *delayed; | |
2010 | int empty; | |
2011 | ||
2012 | spin_lock(&fs_info->delayed_iput_lock); | |
2013 | empty = list_empty(&fs_info->delayed_iputs); | |
2014 | spin_unlock(&fs_info->delayed_iput_lock); | |
2015 | if (empty) | |
2016 | return; | |
2017 | ||
2018 | down_read(&root->fs_info->cleanup_work_sem); | |
2019 | spin_lock(&fs_info->delayed_iput_lock); | |
2020 | list_splice_init(&fs_info->delayed_iputs, &list); | |
2021 | spin_unlock(&fs_info->delayed_iput_lock); | |
2022 | ||
2023 | while (!list_empty(&list)) { | |
2024 | delayed = list_entry(list.next, struct delayed_iput, list); | |
2025 | list_del(&delayed->list); | |
2026 | iput(delayed->inode); | |
2027 | kfree(delayed); | |
2028 | } | |
2029 | up_read(&root->fs_info->cleanup_work_sem); | |
2030 | } | |
2031 | ||
2032 | /* | |
2033 | * calculate extra metadata reservation when snapshotting a subvolume | |
2034 | * contains orphan files. | |
2035 | */ | |
2036 | void btrfs_orphan_pre_snapshot(struct btrfs_trans_handle *trans, | |
2037 | struct btrfs_pending_snapshot *pending, | |
2038 | u64 *bytes_to_reserve) | |
2039 | { | |
2040 | struct btrfs_root *root; | |
2041 | struct btrfs_block_rsv *block_rsv; | |
2042 | u64 num_bytes; | |
2043 | int index; | |
2044 | ||
2045 | root = pending->root; | |
2046 | if (!root->orphan_block_rsv || list_empty(&root->orphan_list)) | |
2047 | return; | |
2048 | ||
2049 | block_rsv = root->orphan_block_rsv; | |
2050 | ||
2051 | /* orphan block reservation for the snapshot */ | |
2052 | num_bytes = block_rsv->size; | |
2053 | ||
2054 | /* | |
2055 | * after the snapshot is created, COWing tree blocks may use more | |
2056 | * space than it frees. So we should make sure there is enough | |
2057 | * reserved space. | |
2058 | */ | |
2059 | index = trans->transid & 0x1; | |
2060 | if (block_rsv->reserved + block_rsv->freed[index] < block_rsv->size) { | |
2061 | num_bytes += block_rsv->size - | |
2062 | (block_rsv->reserved + block_rsv->freed[index]); | |
2063 | } | |
2064 | ||
2065 | *bytes_to_reserve += num_bytes; | |
2066 | } | |
2067 | ||
2068 | void btrfs_orphan_post_snapshot(struct btrfs_trans_handle *trans, | |
2069 | struct btrfs_pending_snapshot *pending) | |
2070 | { | |
2071 | struct btrfs_root *root = pending->root; | |
2072 | struct btrfs_root *snap = pending->snap; | |
2073 | struct btrfs_block_rsv *block_rsv; | |
2074 | u64 num_bytes; | |
2075 | int index; | |
2076 | int ret; | |
2077 | ||
2078 | if (!root->orphan_block_rsv || list_empty(&root->orphan_list)) | |
2079 | return; | |
2080 | ||
2081 | /* refill source subvolume's orphan block reservation */ | |
2082 | block_rsv = root->orphan_block_rsv; | |
2083 | index = trans->transid & 0x1; | |
2084 | if (block_rsv->reserved + block_rsv->freed[index] < block_rsv->size) { | |
2085 | num_bytes = block_rsv->size - | |
2086 | (block_rsv->reserved + block_rsv->freed[index]); | |
2087 | ret = btrfs_block_rsv_migrate(&pending->block_rsv, | |
2088 | root->orphan_block_rsv, | |
2089 | num_bytes); | |
2090 | BUG_ON(ret); | |
2091 | } | |
2092 | ||
2093 | /* setup orphan block reservation for the snapshot */ | |
2094 | block_rsv = btrfs_alloc_block_rsv(snap); | |
2095 | BUG_ON(!block_rsv); | |
2096 | ||
2097 | btrfs_add_durable_block_rsv(root->fs_info, block_rsv); | |
2098 | snap->orphan_block_rsv = block_rsv; | |
2099 | ||
2100 | num_bytes = root->orphan_block_rsv->size; | |
2101 | ret = btrfs_block_rsv_migrate(&pending->block_rsv, | |
2102 | block_rsv, num_bytes); | |
2103 | BUG_ON(ret); | |
2104 | ||
2105 | #if 0 | |
2106 | /* insert orphan item for the snapshot */ | |
2107 | WARN_ON(!root->orphan_item_inserted); | |
2108 | ret = btrfs_insert_orphan_item(trans, root->fs_info->tree_root, | |
2109 | snap->root_key.objectid); | |
2110 | BUG_ON(ret); | |
2111 | snap->orphan_item_inserted = 1; | |
2112 | #endif | |
2113 | } | |
2114 | ||
2115 | enum btrfs_orphan_cleanup_state { | |
2116 | ORPHAN_CLEANUP_STARTED = 1, | |
2117 | ORPHAN_CLEANUP_DONE = 2, | |
2118 | }; | |
2119 | ||
2120 | /* | |
2121 | * This is called in transaction commmit time. If there are no orphan | |
2122 | * files in the subvolume, it removes orphan item and frees block_rsv | |
2123 | * structure. | |
2124 | */ | |
2125 | void btrfs_orphan_commit_root(struct btrfs_trans_handle *trans, | |
2126 | struct btrfs_root *root) | |
2127 | { | |
2128 | int ret; | |
2129 | ||
2130 | if (!list_empty(&root->orphan_list) || | |
2131 | root->orphan_cleanup_state != ORPHAN_CLEANUP_DONE) | |
2132 | return; | |
2133 | ||
2134 | if (root->orphan_item_inserted && | |
2135 | btrfs_root_refs(&root->root_item) > 0) { | |
2136 | ret = btrfs_del_orphan_item(trans, root->fs_info->tree_root, | |
2137 | root->root_key.objectid); | |
2138 | BUG_ON(ret); | |
2139 | root->orphan_item_inserted = 0; | |
2140 | } | |
2141 | ||
2142 | if (root->orphan_block_rsv) { | |
2143 | WARN_ON(root->orphan_block_rsv->size > 0); | |
2144 | btrfs_free_block_rsv(root, root->orphan_block_rsv); | |
2145 | root->orphan_block_rsv = NULL; | |
2146 | } | |
2147 | } | |
2148 | ||
2149 | /* | |
2150 | * This creates an orphan entry for the given inode in case something goes | |
2151 | * wrong in the middle of an unlink/truncate. | |
2152 | * | |
2153 | * NOTE: caller of this function should reserve 5 units of metadata for | |
2154 | * this function. | |
2155 | */ | |
2156 | int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct inode *inode) | |
2157 | { | |
2158 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
2159 | struct btrfs_block_rsv *block_rsv = NULL; | |
2160 | int reserve = 0; | |
2161 | int insert = 0; | |
2162 | int ret; | |
2163 | ||
2164 | if (!root->orphan_block_rsv) { | |
2165 | block_rsv = btrfs_alloc_block_rsv(root); | |
2166 | BUG_ON(!block_rsv); | |
2167 | } | |
2168 | ||
2169 | spin_lock(&root->orphan_lock); | |
2170 | if (!root->orphan_block_rsv) { | |
2171 | root->orphan_block_rsv = block_rsv; | |
2172 | } else if (block_rsv) { | |
2173 | btrfs_free_block_rsv(root, block_rsv); | |
2174 | block_rsv = NULL; | |
2175 | } | |
2176 | ||
2177 | if (list_empty(&BTRFS_I(inode)->i_orphan)) { | |
2178 | list_add(&BTRFS_I(inode)->i_orphan, &root->orphan_list); | |
2179 | #if 0 | |
2180 | /* | |
2181 | * For proper ENOSPC handling, we should do orphan | |
2182 | * cleanup when mounting. But this introduces backward | |
2183 | * compatibility issue. | |
2184 | */ | |
2185 | if (!xchg(&root->orphan_item_inserted, 1)) | |
2186 | insert = 2; | |
2187 | else | |
2188 | insert = 1; | |
2189 | #endif | |
2190 | insert = 1; | |
2191 | } else { | |
2192 | WARN_ON(!BTRFS_I(inode)->orphan_meta_reserved); | |
2193 | } | |
2194 | ||
2195 | if (!BTRFS_I(inode)->orphan_meta_reserved) { | |
2196 | BTRFS_I(inode)->orphan_meta_reserved = 1; | |
2197 | reserve = 1; | |
2198 | } | |
2199 | spin_unlock(&root->orphan_lock); | |
2200 | ||
2201 | if (block_rsv) | |
2202 | btrfs_add_durable_block_rsv(root->fs_info, block_rsv); | |
2203 | ||
2204 | /* grab metadata reservation from transaction handle */ | |
2205 | if (reserve) { | |
2206 | ret = btrfs_orphan_reserve_metadata(trans, inode); | |
2207 | BUG_ON(ret); | |
2208 | } | |
2209 | ||
2210 | /* insert an orphan item to track this unlinked/truncated file */ | |
2211 | if (insert >= 1) { | |
2212 | ret = btrfs_insert_orphan_item(trans, root, inode->i_ino); | |
2213 | BUG_ON(ret); | |
2214 | } | |
2215 | ||
2216 | /* insert an orphan item to track subvolume contains orphan files */ | |
2217 | if (insert >= 2) { | |
2218 | ret = btrfs_insert_orphan_item(trans, root->fs_info->tree_root, | |
2219 | root->root_key.objectid); | |
2220 | BUG_ON(ret); | |
2221 | } | |
2222 | return 0; | |
2223 | } | |
2224 | ||
2225 | /* | |
2226 | * We have done the truncate/delete so we can go ahead and remove the orphan | |
2227 | * item for this particular inode. | |
2228 | */ | |
2229 | int btrfs_orphan_del(struct btrfs_trans_handle *trans, struct inode *inode) | |
2230 | { | |
2231 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
2232 | int delete_item = 0; | |
2233 | int release_rsv = 0; | |
2234 | int ret = 0; | |
2235 | ||
2236 | spin_lock(&root->orphan_lock); | |
2237 | if (!list_empty(&BTRFS_I(inode)->i_orphan)) { | |
2238 | list_del_init(&BTRFS_I(inode)->i_orphan); | |
2239 | delete_item = 1; | |
2240 | } | |
2241 | ||
2242 | if (BTRFS_I(inode)->orphan_meta_reserved) { | |
2243 | BTRFS_I(inode)->orphan_meta_reserved = 0; | |
2244 | release_rsv = 1; | |
2245 | } | |
2246 | spin_unlock(&root->orphan_lock); | |
2247 | ||
2248 | if (trans && delete_item) { | |
2249 | ret = btrfs_del_orphan_item(trans, root, inode->i_ino); | |
2250 | BUG_ON(ret); | |
2251 | } | |
2252 | ||
2253 | if (release_rsv) | |
2254 | btrfs_orphan_release_metadata(inode); | |
2255 | ||
2256 | return 0; | |
2257 | } | |
2258 | ||
2259 | /* | |
2260 | * this cleans up any orphans that may be left on the list from the last use | |
2261 | * of this root. | |
2262 | */ | |
2263 | void btrfs_orphan_cleanup(struct btrfs_root *root) | |
2264 | { | |
2265 | struct btrfs_path *path; | |
2266 | struct extent_buffer *leaf; | |
2267 | struct btrfs_key key, found_key; | |
2268 | struct btrfs_trans_handle *trans; | |
2269 | struct inode *inode; | |
2270 | int ret = 0, nr_unlink = 0, nr_truncate = 0; | |
2271 | ||
2272 | if (cmpxchg(&root->orphan_cleanup_state, 0, ORPHAN_CLEANUP_STARTED)) | |
2273 | return; | |
2274 | ||
2275 | path = btrfs_alloc_path(); | |
2276 | BUG_ON(!path); | |
2277 | path->reada = -1; | |
2278 | ||
2279 | key.objectid = BTRFS_ORPHAN_OBJECTID; | |
2280 | btrfs_set_key_type(&key, BTRFS_ORPHAN_ITEM_KEY); | |
2281 | key.offset = (u64)-1; | |
2282 | ||
2283 | while (1) { | |
2284 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); | |
2285 | if (ret < 0) { | |
2286 | printk(KERN_ERR "Error searching slot for orphan: %d" | |
2287 | "\n", ret); | |
2288 | break; | |
2289 | } | |
2290 | ||
2291 | /* | |
2292 | * if ret == 0 means we found what we were searching for, which | |
2293 | * is weird, but possible, so only screw with path if we didnt | |
2294 | * find the key and see if we have stuff that matches | |
2295 | */ | |
2296 | if (ret > 0) { | |
2297 | if (path->slots[0] == 0) | |
2298 | break; | |
2299 | path->slots[0]--; | |
2300 | } | |
2301 | ||
2302 | /* pull out the item */ | |
2303 | leaf = path->nodes[0]; | |
2304 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); | |
2305 | ||
2306 | /* make sure the item matches what we want */ | |
2307 | if (found_key.objectid != BTRFS_ORPHAN_OBJECTID) | |
2308 | break; | |
2309 | if (btrfs_key_type(&found_key) != BTRFS_ORPHAN_ITEM_KEY) | |
2310 | break; | |
2311 | ||
2312 | /* release the path since we're done with it */ | |
2313 | btrfs_release_path(root, path); | |
2314 | ||
2315 | /* | |
2316 | * this is where we are basically btrfs_lookup, without the | |
2317 | * crossing root thing. we store the inode number in the | |
2318 | * offset of the orphan item. | |
2319 | */ | |
2320 | found_key.objectid = found_key.offset; | |
2321 | found_key.type = BTRFS_INODE_ITEM_KEY; | |
2322 | found_key.offset = 0; | |
2323 | inode = btrfs_iget(root->fs_info->sb, &found_key, root, NULL); | |
2324 | BUG_ON(IS_ERR(inode)); | |
2325 | ||
2326 | /* | |
2327 | * add this inode to the orphan list so btrfs_orphan_del does | |
2328 | * the proper thing when we hit it | |
2329 | */ | |
2330 | spin_lock(&root->orphan_lock); | |
2331 | list_add(&BTRFS_I(inode)->i_orphan, &root->orphan_list); | |
2332 | spin_unlock(&root->orphan_lock); | |
2333 | ||
2334 | /* | |
2335 | * if this is a bad inode, means we actually succeeded in | |
2336 | * removing the inode, but not the orphan record, which means | |
2337 | * we need to manually delete the orphan since iput will just | |
2338 | * do a destroy_inode | |
2339 | */ | |
2340 | if (is_bad_inode(inode)) { | |
2341 | trans = btrfs_start_transaction(root, 0); | |
2342 | btrfs_orphan_del(trans, inode); | |
2343 | btrfs_end_transaction(trans, root); | |
2344 | iput(inode); | |
2345 | continue; | |
2346 | } | |
2347 | ||
2348 | /* if we have links, this was a truncate, lets do that */ | |
2349 | if (inode->i_nlink) { | |
2350 | nr_truncate++; | |
2351 | btrfs_truncate(inode); | |
2352 | } else { | |
2353 | nr_unlink++; | |
2354 | } | |
2355 | ||
2356 | /* this will do delete_inode and everything for us */ | |
2357 | iput(inode); | |
2358 | } | |
2359 | btrfs_free_path(path); | |
2360 | ||
2361 | root->orphan_cleanup_state = ORPHAN_CLEANUP_DONE; | |
2362 | ||
2363 | if (root->orphan_block_rsv) | |
2364 | btrfs_block_rsv_release(root, root->orphan_block_rsv, | |
2365 | (u64)-1); | |
2366 | ||
2367 | if (root->orphan_block_rsv || root->orphan_item_inserted) { | |
2368 | trans = btrfs_join_transaction(root, 1); | |
2369 | btrfs_end_transaction(trans, root); | |
2370 | } | |
2371 | ||
2372 | if (nr_unlink) | |
2373 | printk(KERN_INFO "btrfs: unlinked %d orphans\n", nr_unlink); | |
2374 | if (nr_truncate) | |
2375 | printk(KERN_INFO "btrfs: truncated %d orphans\n", nr_truncate); | |
2376 | } | |
2377 | ||
2378 | /* | |
2379 | * very simple check to peek ahead in the leaf looking for xattrs. If we | |
2380 | * don't find any xattrs, we know there can't be any acls. | |
2381 | * | |
2382 | * slot is the slot the inode is in, objectid is the objectid of the inode | |
2383 | */ | |
2384 | static noinline int acls_after_inode_item(struct extent_buffer *leaf, | |
2385 | int slot, u64 objectid) | |
2386 | { | |
2387 | u32 nritems = btrfs_header_nritems(leaf); | |
2388 | struct btrfs_key found_key; | |
2389 | int scanned = 0; | |
2390 | ||
2391 | slot++; | |
2392 | while (slot < nritems) { | |
2393 | btrfs_item_key_to_cpu(leaf, &found_key, slot); | |
2394 | ||
2395 | /* we found a different objectid, there must not be acls */ | |
2396 | if (found_key.objectid != objectid) | |
2397 | return 0; | |
2398 | ||
2399 | /* we found an xattr, assume we've got an acl */ | |
2400 | if (found_key.type == BTRFS_XATTR_ITEM_KEY) | |
2401 | return 1; | |
2402 | ||
2403 | /* | |
2404 | * we found a key greater than an xattr key, there can't | |
2405 | * be any acls later on | |
2406 | */ | |
2407 | if (found_key.type > BTRFS_XATTR_ITEM_KEY) | |
2408 | return 0; | |
2409 | ||
2410 | slot++; | |
2411 | scanned++; | |
2412 | ||
2413 | /* | |
2414 | * it goes inode, inode backrefs, xattrs, extents, | |
2415 | * so if there are a ton of hard links to an inode there can | |
2416 | * be a lot of backrefs. Don't waste time searching too hard, | |
2417 | * this is just an optimization | |
2418 | */ | |
2419 | if (scanned >= 8) | |
2420 | break; | |
2421 | } | |
2422 | /* we hit the end of the leaf before we found an xattr or | |
2423 | * something larger than an xattr. We have to assume the inode | |
2424 | * has acls | |
2425 | */ | |
2426 | return 1; | |
2427 | } | |
2428 | ||
2429 | /* | |
2430 | * read an inode from the btree into the in-memory inode | |
2431 | */ | |
2432 | static void btrfs_read_locked_inode(struct inode *inode) | |
2433 | { | |
2434 | struct btrfs_path *path; | |
2435 | struct extent_buffer *leaf; | |
2436 | struct btrfs_inode_item *inode_item; | |
2437 | struct btrfs_timespec *tspec; | |
2438 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
2439 | struct btrfs_key location; | |
2440 | int maybe_acls; | |
2441 | u64 alloc_group_block; | |
2442 | u32 rdev; | |
2443 | int ret; | |
2444 | ||
2445 | path = btrfs_alloc_path(); | |
2446 | BUG_ON(!path); | |
2447 | memcpy(&location, &BTRFS_I(inode)->location, sizeof(location)); | |
2448 | ||
2449 | ret = btrfs_lookup_inode(NULL, root, path, &location, 0); | |
2450 | if (ret) | |
2451 | goto make_bad; | |
2452 | ||
2453 | leaf = path->nodes[0]; | |
2454 | inode_item = btrfs_item_ptr(leaf, path->slots[0], | |
2455 | struct btrfs_inode_item); | |
2456 | ||
2457 | inode->i_mode = btrfs_inode_mode(leaf, inode_item); | |
2458 | inode->i_nlink = btrfs_inode_nlink(leaf, inode_item); | |
2459 | inode->i_uid = btrfs_inode_uid(leaf, inode_item); | |
2460 | inode->i_gid = btrfs_inode_gid(leaf, inode_item); | |
2461 | btrfs_i_size_write(inode, btrfs_inode_size(leaf, inode_item)); | |
2462 | ||
2463 | tspec = btrfs_inode_atime(inode_item); | |
2464 | inode->i_atime.tv_sec = btrfs_timespec_sec(leaf, tspec); | |
2465 | inode->i_atime.tv_nsec = btrfs_timespec_nsec(leaf, tspec); | |
2466 | ||
2467 | tspec = btrfs_inode_mtime(inode_item); | |
2468 | inode->i_mtime.tv_sec = btrfs_timespec_sec(leaf, tspec); | |
2469 | inode->i_mtime.tv_nsec = btrfs_timespec_nsec(leaf, tspec); | |
2470 | ||
2471 | tspec = btrfs_inode_ctime(inode_item); | |
2472 | inode->i_ctime.tv_sec = btrfs_timespec_sec(leaf, tspec); | |
2473 | inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, tspec); | |
2474 | ||
2475 | inode_set_bytes(inode, btrfs_inode_nbytes(leaf, inode_item)); | |
2476 | BTRFS_I(inode)->generation = btrfs_inode_generation(leaf, inode_item); | |
2477 | BTRFS_I(inode)->sequence = btrfs_inode_sequence(leaf, inode_item); | |
2478 | inode->i_generation = BTRFS_I(inode)->generation; | |
2479 | inode->i_rdev = 0; | |
2480 | rdev = btrfs_inode_rdev(leaf, inode_item); | |
2481 | ||
2482 | BTRFS_I(inode)->index_cnt = (u64)-1; | |
2483 | BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item); | |
2484 | ||
2485 | alloc_group_block = btrfs_inode_block_group(leaf, inode_item); | |
2486 | ||
2487 | /* | |
2488 | * try to precache a NULL acl entry for files that don't have | |
2489 | * any xattrs or acls | |
2490 | */ | |
2491 | maybe_acls = acls_after_inode_item(leaf, path->slots[0], inode->i_ino); | |
2492 | if (!maybe_acls) | |
2493 | cache_no_acl(inode); | |
2494 | ||
2495 | BTRFS_I(inode)->block_group = btrfs_find_block_group(root, 0, | |
2496 | alloc_group_block, 0); | |
2497 | btrfs_free_path(path); | |
2498 | inode_item = NULL; | |
2499 | ||
2500 | switch (inode->i_mode & S_IFMT) { | |
2501 | case S_IFREG: | |
2502 | inode->i_mapping->a_ops = &btrfs_aops; | |
2503 | inode->i_mapping->backing_dev_info = &root->fs_info->bdi; | |
2504 | BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; | |
2505 | inode->i_fop = &btrfs_file_operations; | |
2506 | inode->i_op = &btrfs_file_inode_operations; | |
2507 | break; | |
2508 | case S_IFDIR: | |
2509 | inode->i_fop = &btrfs_dir_file_operations; | |
2510 | if (root == root->fs_info->tree_root) | |
2511 | inode->i_op = &btrfs_dir_ro_inode_operations; | |
2512 | else | |
2513 | inode->i_op = &btrfs_dir_inode_operations; | |
2514 | break; | |
2515 | case S_IFLNK: | |
2516 | inode->i_op = &btrfs_symlink_inode_operations; | |
2517 | inode->i_mapping->a_ops = &btrfs_symlink_aops; | |
2518 | inode->i_mapping->backing_dev_info = &root->fs_info->bdi; | |
2519 | break; | |
2520 | default: | |
2521 | inode->i_op = &btrfs_special_inode_operations; | |
2522 | init_special_inode(inode, inode->i_mode, rdev); | |
2523 | break; | |
2524 | } | |
2525 | ||
2526 | btrfs_update_iflags(inode); | |
2527 | return; | |
2528 | ||
2529 | make_bad: | |
2530 | btrfs_free_path(path); | |
2531 | make_bad_inode(inode); | |
2532 | } | |
2533 | ||
2534 | /* | |
2535 | * given a leaf and an inode, copy the inode fields into the leaf | |
2536 | */ | |
2537 | static void fill_inode_item(struct btrfs_trans_handle *trans, | |
2538 | struct extent_buffer *leaf, | |
2539 | struct btrfs_inode_item *item, | |
2540 | struct inode *inode) | |
2541 | { | |
2542 | btrfs_set_inode_uid(leaf, item, inode->i_uid); | |
2543 | btrfs_set_inode_gid(leaf, item, inode->i_gid); | |
2544 | btrfs_set_inode_size(leaf, item, BTRFS_I(inode)->disk_i_size); | |
2545 | btrfs_set_inode_mode(leaf, item, inode->i_mode); | |
2546 | btrfs_set_inode_nlink(leaf, item, inode->i_nlink); | |
2547 | ||
2548 | btrfs_set_timespec_sec(leaf, btrfs_inode_atime(item), | |
2549 | inode->i_atime.tv_sec); | |
2550 | btrfs_set_timespec_nsec(leaf, btrfs_inode_atime(item), | |
2551 | inode->i_atime.tv_nsec); | |
2552 | ||
2553 | btrfs_set_timespec_sec(leaf, btrfs_inode_mtime(item), | |
2554 | inode->i_mtime.tv_sec); | |
2555 | btrfs_set_timespec_nsec(leaf, btrfs_inode_mtime(item), | |
2556 | inode->i_mtime.tv_nsec); | |
2557 | ||
2558 | btrfs_set_timespec_sec(leaf, btrfs_inode_ctime(item), | |
2559 | inode->i_ctime.tv_sec); | |
2560 | btrfs_set_timespec_nsec(leaf, btrfs_inode_ctime(item), | |
2561 | inode->i_ctime.tv_nsec); | |
2562 | ||
2563 | btrfs_set_inode_nbytes(leaf, item, inode_get_bytes(inode)); | |
2564 | btrfs_set_inode_generation(leaf, item, BTRFS_I(inode)->generation); | |
2565 | btrfs_set_inode_sequence(leaf, item, BTRFS_I(inode)->sequence); | |
2566 | btrfs_set_inode_transid(leaf, item, trans->transid); | |
2567 | btrfs_set_inode_rdev(leaf, item, inode->i_rdev); | |
2568 | btrfs_set_inode_flags(leaf, item, BTRFS_I(inode)->flags); | |
2569 | btrfs_set_inode_block_group(leaf, item, BTRFS_I(inode)->block_group); | |
2570 | } | |
2571 | ||
2572 | /* | |
2573 | * copy everything in the in-memory inode into the btree. | |
2574 | */ | |
2575 | noinline int btrfs_update_inode(struct btrfs_trans_handle *trans, | |
2576 | struct btrfs_root *root, struct inode *inode) | |
2577 | { | |
2578 | struct btrfs_inode_item *inode_item; | |
2579 | struct btrfs_path *path; | |
2580 | struct extent_buffer *leaf; | |
2581 | int ret; | |
2582 | ||
2583 | path = btrfs_alloc_path(); | |
2584 | BUG_ON(!path); | |
2585 | path->leave_spinning = 1; | |
2586 | ret = btrfs_lookup_inode(trans, root, path, | |
2587 | &BTRFS_I(inode)->location, 1); | |
2588 | if (ret) { | |
2589 | if (ret > 0) | |
2590 | ret = -ENOENT; | |
2591 | goto failed; | |
2592 | } | |
2593 | ||
2594 | btrfs_unlock_up_safe(path, 1); | |
2595 | leaf = path->nodes[0]; | |
2596 | inode_item = btrfs_item_ptr(leaf, path->slots[0], | |
2597 | struct btrfs_inode_item); | |
2598 | ||
2599 | fill_inode_item(trans, leaf, inode_item, inode); | |
2600 | btrfs_mark_buffer_dirty(leaf); | |
2601 | btrfs_set_inode_last_trans(trans, inode); | |
2602 | ret = 0; | |
2603 | failed: | |
2604 | btrfs_free_path(path); | |
2605 | return ret; | |
2606 | } | |
2607 | ||
2608 | ||
2609 | /* | |
2610 | * unlink helper that gets used here in inode.c and in the tree logging | |
2611 | * recovery code. It remove a link in a directory with a given name, and | |
2612 | * also drops the back refs in the inode to the directory | |
2613 | */ | |
2614 | int btrfs_unlink_inode(struct btrfs_trans_handle *trans, | |
2615 | struct btrfs_root *root, | |
2616 | struct inode *dir, struct inode *inode, | |
2617 | const char *name, int name_len) | |
2618 | { | |
2619 | struct btrfs_path *path; | |
2620 | int ret = 0; | |
2621 | struct extent_buffer *leaf; | |
2622 | struct btrfs_dir_item *di; | |
2623 | struct btrfs_key key; | |
2624 | u64 index; | |
2625 | ||
2626 | path = btrfs_alloc_path(); | |
2627 | if (!path) { | |
2628 | ret = -ENOMEM; | |
2629 | goto err; | |
2630 | } | |
2631 | ||
2632 | path->leave_spinning = 1; | |
2633 | di = btrfs_lookup_dir_item(trans, root, path, dir->i_ino, | |
2634 | name, name_len, -1); | |
2635 | if (IS_ERR(di)) { | |
2636 | ret = PTR_ERR(di); | |
2637 | goto err; | |
2638 | } | |
2639 | if (!di) { | |
2640 | ret = -ENOENT; | |
2641 | goto err; | |
2642 | } | |
2643 | leaf = path->nodes[0]; | |
2644 | btrfs_dir_item_key_to_cpu(leaf, di, &key); | |
2645 | ret = btrfs_delete_one_dir_name(trans, root, path, di); | |
2646 | if (ret) | |
2647 | goto err; | |
2648 | btrfs_release_path(root, path); | |
2649 | ||
2650 | ret = btrfs_del_inode_ref(trans, root, name, name_len, | |
2651 | inode->i_ino, | |
2652 | dir->i_ino, &index); | |
2653 | if (ret) { | |
2654 | printk(KERN_INFO "btrfs failed to delete reference to %.*s, " | |
2655 | "inode %lu parent %lu\n", name_len, name, | |
2656 | inode->i_ino, dir->i_ino); | |
2657 | goto err; | |
2658 | } | |
2659 | ||
2660 | di = btrfs_lookup_dir_index_item(trans, root, path, dir->i_ino, | |
2661 | index, name, name_len, -1); | |
2662 | if (IS_ERR(di)) { | |
2663 | ret = PTR_ERR(di); | |
2664 | goto err; | |
2665 | } | |
2666 | if (!di) { | |
2667 | ret = -ENOENT; | |
2668 | goto err; | |
2669 | } | |
2670 | ret = btrfs_delete_one_dir_name(trans, root, path, di); | |
2671 | btrfs_release_path(root, path); | |
2672 | ||
2673 | ret = btrfs_del_inode_ref_in_log(trans, root, name, name_len, | |
2674 | inode, dir->i_ino); | |
2675 | BUG_ON(ret != 0 && ret != -ENOENT); | |
2676 | ||
2677 | ret = btrfs_del_dir_entries_in_log(trans, root, name, name_len, | |
2678 | dir, index); | |
2679 | if (ret == -ENOENT) | |
2680 | ret = 0; | |
2681 | err: | |
2682 | btrfs_free_path(path); | |
2683 | if (ret) | |
2684 | goto out; | |
2685 | ||
2686 | btrfs_i_size_write(dir, dir->i_size - name_len * 2); | |
2687 | inode->i_ctime = dir->i_mtime = dir->i_ctime = CURRENT_TIME; | |
2688 | btrfs_update_inode(trans, root, dir); | |
2689 | btrfs_drop_nlink(inode); | |
2690 | ret = btrfs_update_inode(trans, root, inode); | |
2691 | out: | |
2692 | return ret; | |
2693 | } | |
2694 | ||
2695 | /* helper to check if there is any shared block in the path */ | |
2696 | static int check_path_shared(struct btrfs_root *root, | |
2697 | struct btrfs_path *path) | |
2698 | { | |
2699 | struct extent_buffer *eb; | |
2700 | int level; | |
2701 | u64 refs = 1; | |
2702 | int uninitialized_var(ret); | |
2703 | ||
2704 | for (level = 0; level < BTRFS_MAX_LEVEL; level++) { | |
2705 | if (!path->nodes[level]) | |
2706 | break; | |
2707 | eb = path->nodes[level]; | |
2708 | if (!btrfs_block_can_be_shared(root, eb)) | |
2709 | continue; | |
2710 | ret = btrfs_lookup_extent_info(NULL, root, eb->start, eb->len, | |
2711 | &refs, NULL); | |
2712 | if (refs > 1) | |
2713 | return 1; | |
2714 | } | |
2715 | return ret; /* XXX callers? */ | |
2716 | } | |
2717 | ||
2718 | /* | |
2719 | * helper to start transaction for unlink and rmdir. | |
2720 | * | |
2721 | * unlink and rmdir are special in btrfs, they do not always free space. | |
2722 | * so in enospc case, we should make sure they will free space before | |
2723 | * allowing them to use the global metadata reservation. | |
2724 | */ | |
2725 | static struct btrfs_trans_handle *__unlink_start_trans(struct inode *dir, | |
2726 | struct dentry *dentry) | |
2727 | { | |
2728 | struct btrfs_trans_handle *trans; | |
2729 | struct btrfs_root *root = BTRFS_I(dir)->root; | |
2730 | struct btrfs_path *path; | |
2731 | struct btrfs_inode_ref *ref; | |
2732 | struct btrfs_dir_item *di; | |
2733 | struct inode *inode = dentry->d_inode; | |
2734 | u64 index; | |
2735 | int check_link = 1; | |
2736 | int err = -ENOSPC; | |
2737 | int ret; | |
2738 | ||
2739 | trans = btrfs_start_transaction(root, 10); | |
2740 | if (!IS_ERR(trans) || PTR_ERR(trans) != -ENOSPC) | |
2741 | return trans; | |
2742 | ||
2743 | if (inode->i_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID) | |
2744 | return ERR_PTR(-ENOSPC); | |
2745 | ||
2746 | /* check if there is someone else holds reference */ | |
2747 | if (S_ISDIR(inode->i_mode) && atomic_read(&inode->i_count) > 1) | |
2748 | return ERR_PTR(-ENOSPC); | |
2749 | ||
2750 | if (atomic_read(&inode->i_count) > 2) | |
2751 | return ERR_PTR(-ENOSPC); | |
2752 | ||
2753 | if (xchg(&root->fs_info->enospc_unlink, 1)) | |
2754 | return ERR_PTR(-ENOSPC); | |
2755 | ||
2756 | path = btrfs_alloc_path(); | |
2757 | if (!path) { | |
2758 | root->fs_info->enospc_unlink = 0; | |
2759 | return ERR_PTR(-ENOMEM); | |
2760 | } | |
2761 | ||
2762 | trans = btrfs_start_transaction(root, 0); | |
2763 | if (IS_ERR(trans)) { | |
2764 | btrfs_free_path(path); | |
2765 | root->fs_info->enospc_unlink = 0; | |
2766 | return trans; | |
2767 | } | |
2768 | ||
2769 | path->skip_locking = 1; | |
2770 | path->search_commit_root = 1; | |
2771 | ||
2772 | ret = btrfs_lookup_inode(trans, root, path, | |
2773 | &BTRFS_I(dir)->location, 0); | |
2774 | if (ret < 0) { | |
2775 | err = ret; | |
2776 | goto out; | |
2777 | } | |
2778 | if (ret == 0) { | |
2779 | if (check_path_shared(root, path)) | |
2780 | goto out; | |
2781 | } else { | |
2782 | check_link = 0; | |
2783 | } | |
2784 | btrfs_release_path(root, path); | |
2785 | ||
2786 | ret = btrfs_lookup_inode(trans, root, path, | |
2787 | &BTRFS_I(inode)->location, 0); | |
2788 | if (ret < 0) { | |
2789 | err = ret; | |
2790 | goto out; | |
2791 | } | |
2792 | if (ret == 0) { | |
2793 | if (check_path_shared(root, path)) | |
2794 | goto out; | |
2795 | } else { | |
2796 | check_link = 0; | |
2797 | } | |
2798 | btrfs_release_path(root, path); | |
2799 | ||
2800 | if (ret == 0 && S_ISREG(inode->i_mode)) { | |
2801 | ret = btrfs_lookup_file_extent(trans, root, path, | |
2802 | inode->i_ino, (u64)-1, 0); | |
2803 | if (ret < 0) { | |
2804 | err = ret; | |
2805 | goto out; | |
2806 | } | |
2807 | BUG_ON(ret == 0); | |
2808 | if (check_path_shared(root, path)) | |
2809 | goto out; | |
2810 | btrfs_release_path(root, path); | |
2811 | } | |
2812 | ||
2813 | if (!check_link) { | |
2814 | err = 0; | |
2815 | goto out; | |
2816 | } | |
2817 | ||
2818 | di = btrfs_lookup_dir_item(trans, root, path, dir->i_ino, | |
2819 | dentry->d_name.name, dentry->d_name.len, 0); | |
2820 | if (IS_ERR(di)) { | |
2821 | err = PTR_ERR(di); | |
2822 | goto out; | |
2823 | } | |
2824 | if (di) { | |
2825 | if (check_path_shared(root, path)) | |
2826 | goto out; | |
2827 | } else { | |
2828 | err = 0; | |
2829 | goto out; | |
2830 | } | |
2831 | btrfs_release_path(root, path); | |
2832 | ||
2833 | ref = btrfs_lookup_inode_ref(trans, root, path, | |
2834 | dentry->d_name.name, dentry->d_name.len, | |
2835 | inode->i_ino, dir->i_ino, 0); | |
2836 | if (IS_ERR(ref)) { | |
2837 | err = PTR_ERR(ref); | |
2838 | goto out; | |
2839 | } | |
2840 | BUG_ON(!ref); | |
2841 | if (check_path_shared(root, path)) | |
2842 | goto out; | |
2843 | index = btrfs_inode_ref_index(path->nodes[0], ref); | |
2844 | btrfs_release_path(root, path); | |
2845 | ||
2846 | di = btrfs_lookup_dir_index_item(trans, root, path, dir->i_ino, index, | |
2847 | dentry->d_name.name, dentry->d_name.len, 0); | |
2848 | if (IS_ERR(di)) { | |
2849 | err = PTR_ERR(di); | |
2850 | goto out; | |
2851 | } | |
2852 | BUG_ON(ret == -ENOENT); | |
2853 | if (check_path_shared(root, path)) | |
2854 | goto out; | |
2855 | ||
2856 | err = 0; | |
2857 | out: | |
2858 | btrfs_free_path(path); | |
2859 | if (err) { | |
2860 | btrfs_end_transaction(trans, root); | |
2861 | root->fs_info->enospc_unlink = 0; | |
2862 | return ERR_PTR(err); | |
2863 | } | |
2864 | ||
2865 | trans->block_rsv = &root->fs_info->global_block_rsv; | |
2866 | return trans; | |
2867 | } | |
2868 | ||
2869 | static void __unlink_end_trans(struct btrfs_trans_handle *trans, | |
2870 | struct btrfs_root *root) | |
2871 | { | |
2872 | if (trans->block_rsv == &root->fs_info->global_block_rsv) { | |
2873 | BUG_ON(!root->fs_info->enospc_unlink); | |
2874 | root->fs_info->enospc_unlink = 0; | |
2875 | } | |
2876 | btrfs_end_transaction_throttle(trans, root); | |
2877 | } | |
2878 | ||
2879 | static int btrfs_unlink(struct inode *dir, struct dentry *dentry) | |
2880 | { | |
2881 | struct btrfs_root *root = BTRFS_I(dir)->root; | |
2882 | struct btrfs_trans_handle *trans; | |
2883 | struct inode *inode = dentry->d_inode; | |
2884 | int ret; | |
2885 | unsigned long nr = 0; | |
2886 | ||
2887 | trans = __unlink_start_trans(dir, dentry); | |
2888 | if (IS_ERR(trans)) | |
2889 | return PTR_ERR(trans); | |
2890 | ||
2891 | btrfs_set_trans_block_group(trans, dir); | |
2892 | ||
2893 | btrfs_record_unlink_dir(trans, dir, dentry->d_inode, 0); | |
2894 | ||
2895 | ret = btrfs_unlink_inode(trans, root, dir, dentry->d_inode, | |
2896 | dentry->d_name.name, dentry->d_name.len); | |
2897 | BUG_ON(ret); | |
2898 | ||
2899 | if (inode->i_nlink == 0) { | |
2900 | ret = btrfs_orphan_add(trans, inode); | |
2901 | BUG_ON(ret); | |
2902 | } | |
2903 | ||
2904 | nr = trans->blocks_used; | |
2905 | __unlink_end_trans(trans, root); | |
2906 | btrfs_btree_balance_dirty(root, nr); | |
2907 | return ret; | |
2908 | } | |
2909 | ||
2910 | int btrfs_unlink_subvol(struct btrfs_trans_handle *trans, | |
2911 | struct btrfs_root *root, | |
2912 | struct inode *dir, u64 objectid, | |
2913 | const char *name, int name_len) | |
2914 | { | |
2915 | struct btrfs_path *path; | |
2916 | struct extent_buffer *leaf; | |
2917 | struct btrfs_dir_item *di; | |
2918 | struct btrfs_key key; | |
2919 | u64 index; | |
2920 | int ret; | |
2921 | ||
2922 | path = btrfs_alloc_path(); | |
2923 | if (!path) | |
2924 | return -ENOMEM; | |
2925 | ||
2926 | di = btrfs_lookup_dir_item(trans, root, path, dir->i_ino, | |
2927 | name, name_len, -1); | |
2928 | BUG_ON(!di || IS_ERR(di)); | |
2929 | ||
2930 | leaf = path->nodes[0]; | |
2931 | btrfs_dir_item_key_to_cpu(leaf, di, &key); | |
2932 | WARN_ON(key.type != BTRFS_ROOT_ITEM_KEY || key.objectid != objectid); | |
2933 | ret = btrfs_delete_one_dir_name(trans, root, path, di); | |
2934 | BUG_ON(ret); | |
2935 | btrfs_release_path(root, path); | |
2936 | ||
2937 | ret = btrfs_del_root_ref(trans, root->fs_info->tree_root, | |
2938 | objectid, root->root_key.objectid, | |
2939 | dir->i_ino, &index, name, name_len); | |
2940 | if (ret < 0) { | |
2941 | BUG_ON(ret != -ENOENT); | |
2942 | di = btrfs_search_dir_index_item(root, path, dir->i_ino, | |
2943 | name, name_len); | |
2944 | BUG_ON(!di || IS_ERR(di)); | |
2945 | ||
2946 | leaf = path->nodes[0]; | |
2947 | btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); | |
2948 | btrfs_release_path(root, path); | |
2949 | index = key.offset; | |
2950 | } | |
2951 | ||
2952 | di = btrfs_lookup_dir_index_item(trans, root, path, dir->i_ino, | |
2953 | index, name, name_len, -1); | |
2954 | BUG_ON(!di || IS_ERR(di)); | |
2955 | ||
2956 | leaf = path->nodes[0]; | |
2957 | btrfs_dir_item_key_to_cpu(leaf, di, &key); | |
2958 | WARN_ON(key.type != BTRFS_ROOT_ITEM_KEY || key.objectid != objectid); | |
2959 | ret = btrfs_delete_one_dir_name(trans, root, path, di); | |
2960 | BUG_ON(ret); | |
2961 | btrfs_release_path(root, path); | |
2962 | ||
2963 | btrfs_i_size_write(dir, dir->i_size - name_len * 2); | |
2964 | dir->i_mtime = dir->i_ctime = CURRENT_TIME; | |
2965 | ret = btrfs_update_inode(trans, root, dir); | |
2966 | BUG_ON(ret); | |
2967 | ||
2968 | btrfs_free_path(path); | |
2969 | return 0; | |
2970 | } | |
2971 | ||
2972 | static int btrfs_rmdir(struct inode *dir, struct dentry *dentry) | |
2973 | { | |
2974 | struct inode *inode = dentry->d_inode; | |
2975 | int err = 0; | |
2976 | struct btrfs_root *root = BTRFS_I(dir)->root; | |
2977 | struct btrfs_trans_handle *trans; | |
2978 | unsigned long nr = 0; | |
2979 | ||
2980 | if (inode->i_size > BTRFS_EMPTY_DIR_SIZE || | |
2981 | inode->i_ino == BTRFS_FIRST_FREE_OBJECTID) | |
2982 | return -ENOTEMPTY; | |
2983 | ||
2984 | trans = __unlink_start_trans(dir, dentry); | |
2985 | if (IS_ERR(trans)) | |
2986 | return PTR_ERR(trans); | |
2987 | ||
2988 | btrfs_set_trans_block_group(trans, dir); | |
2989 | ||
2990 | if (unlikely(inode->i_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) { | |
2991 | err = btrfs_unlink_subvol(trans, root, dir, | |
2992 | BTRFS_I(inode)->location.objectid, | |
2993 | dentry->d_name.name, | |
2994 | dentry->d_name.len); | |
2995 | goto out; | |
2996 | } | |
2997 | ||
2998 | err = btrfs_orphan_add(trans, inode); | |
2999 | if (err) | |
3000 | goto out; | |
3001 | ||
3002 | /* now the directory is empty */ | |
3003 | err = btrfs_unlink_inode(trans, root, dir, dentry->d_inode, | |
3004 | dentry->d_name.name, dentry->d_name.len); | |
3005 | if (!err) | |
3006 | btrfs_i_size_write(inode, 0); | |
3007 | out: | |
3008 | nr = trans->blocks_used; | |
3009 | __unlink_end_trans(trans, root); | |
3010 | btrfs_btree_balance_dirty(root, nr); | |
3011 | ||
3012 | return err; | |
3013 | } | |
3014 | ||
3015 | #if 0 | |
3016 | /* | |
3017 | * when truncating bytes in a file, it is possible to avoid reading | |
3018 | * the leaves that contain only checksum items. This can be the | |
3019 | * majority of the IO required to delete a large file, but it must | |
3020 | * be done carefully. | |
3021 | * | |
3022 | * The keys in the level just above the leaves are checked to make sure | |
3023 | * the lowest key in a given leaf is a csum key, and starts at an offset | |
3024 | * after the new size. | |
3025 | * | |
3026 | * Then the key for the next leaf is checked to make sure it also has | |
3027 | * a checksum item for the same file. If it does, we know our target leaf | |
3028 | * contains only checksum items, and it can be safely freed without reading | |
3029 | * it. | |
3030 | * | |
3031 | * This is just an optimization targeted at large files. It may do | |
3032 | * nothing. It will return 0 unless things went badly. | |
3033 | */ | |
3034 | static noinline int drop_csum_leaves(struct btrfs_trans_handle *trans, | |
3035 | struct btrfs_root *root, | |
3036 | struct btrfs_path *path, | |
3037 | struct inode *inode, u64 new_size) | |
3038 | { | |
3039 | struct btrfs_key key; | |
3040 | int ret; | |
3041 | int nritems; | |
3042 | struct btrfs_key found_key; | |
3043 | struct btrfs_key other_key; | |
3044 | struct btrfs_leaf_ref *ref; | |
3045 | u64 leaf_gen; | |
3046 | u64 leaf_start; | |
3047 | ||
3048 | path->lowest_level = 1; | |
3049 | key.objectid = inode->i_ino; | |
3050 | key.type = BTRFS_CSUM_ITEM_KEY; | |
3051 | key.offset = new_size; | |
3052 | again: | |
3053 | ret = btrfs_search_slot(trans, root, &key, path, -1, 1); | |
3054 | if (ret < 0) | |
3055 | goto out; | |
3056 | ||
3057 | if (path->nodes[1] == NULL) { | |
3058 | ret = 0; | |
3059 | goto out; | |
3060 | } | |
3061 | ret = 0; | |
3062 | btrfs_node_key_to_cpu(path->nodes[1], &found_key, path->slots[1]); | |
3063 | nritems = btrfs_header_nritems(path->nodes[1]); | |
3064 | ||
3065 | if (!nritems) | |
3066 | goto out; | |
3067 | ||
3068 | if (path->slots[1] >= nritems) | |
3069 | goto next_node; | |
3070 | ||
3071 | /* did we find a key greater than anything we want to delete? */ | |
3072 | if (found_key.objectid > inode->i_ino || | |
3073 | (found_key.objectid == inode->i_ino && found_key.type > key.type)) | |
3074 | goto out; | |
3075 | ||
3076 | /* we check the next key in the node to make sure the leave contains | |
3077 | * only checksum items. This comparison doesn't work if our | |
3078 | * leaf is the last one in the node | |
3079 | */ | |
3080 | if (path->slots[1] + 1 >= nritems) { | |
3081 | next_node: | |
3082 | /* search forward from the last key in the node, this | |
3083 | * will bring us into the next node in the tree | |
3084 | */ | |
3085 | btrfs_node_key_to_cpu(path->nodes[1], &found_key, nritems - 1); | |
3086 | ||
3087 | /* unlikely, but we inc below, so check to be safe */ | |
3088 | if (found_key.offset == (u64)-1) | |
3089 | goto out; | |
3090 | ||
3091 | /* search_forward needs a path with locks held, do the | |
3092 | * search again for the original key. It is possible | |
3093 | * this will race with a balance and return a path that | |
3094 | * we could modify, but this drop is just an optimization | |
3095 | * and is allowed to miss some leaves. | |
3096 | */ | |
3097 | btrfs_release_path(root, path); | |
3098 | found_key.offset++; | |
3099 | ||
3100 | /* setup a max key for search_forward */ | |
3101 | other_key.offset = (u64)-1; | |
3102 | other_key.type = key.type; | |
3103 | other_key.objectid = key.objectid; | |
3104 | ||
3105 | path->keep_locks = 1; | |
3106 | ret = btrfs_search_forward(root, &found_key, &other_key, | |
3107 | path, 0, 0); | |
3108 | path->keep_locks = 0; | |
3109 | if (ret || found_key.objectid != key.objectid || | |
3110 | found_key.type != key.type) { | |
3111 | ret = 0; | |
3112 | goto out; | |
3113 | } | |
3114 | ||
3115 | key.offset = found_key.offset; | |
3116 | btrfs_release_path(root, path); | |
3117 | cond_resched(); | |
3118 | goto again; | |
3119 | } | |
3120 | ||
3121 | /* we know there's one more slot after us in the tree, | |
3122 | * read that key so we can verify it is also a checksum item | |
3123 | */ | |
3124 | btrfs_node_key_to_cpu(path->nodes[1], &other_key, path->slots[1] + 1); | |
3125 | ||
3126 | if (found_key.objectid < inode->i_ino) | |
3127 | goto next_key; | |
3128 | ||
3129 | if (found_key.type != key.type || found_key.offset < new_size) | |
3130 | goto next_key; | |
3131 | ||
3132 | /* | |
3133 | * if the key for the next leaf isn't a csum key from this objectid, | |
3134 | * we can't be sure there aren't good items inside this leaf. | |
3135 | * Bail out | |
3136 | */ | |
3137 | if (other_key.objectid != inode->i_ino || other_key.type != key.type) | |
3138 | goto out; | |
3139 | ||
3140 | leaf_start = btrfs_node_blockptr(path->nodes[1], path->slots[1]); | |
3141 | leaf_gen = btrfs_node_ptr_generation(path->nodes[1], path->slots[1]); | |
3142 | /* | |
3143 | * it is safe to delete this leaf, it contains only | |
3144 | * csum items from this inode at an offset >= new_size | |
3145 | */ | |
3146 | ret = btrfs_del_leaf(trans, root, path, leaf_start); | |
3147 | BUG_ON(ret); | |
3148 | ||
3149 | if (root->ref_cows && leaf_gen < trans->transid) { | |
3150 | ref = btrfs_alloc_leaf_ref(root, 0); | |
3151 | if (ref) { | |
3152 | ref->root_gen = root->root_key.offset; | |
3153 | ref->bytenr = leaf_start; | |
3154 | ref->owner = 0; | |
3155 | ref->generation = leaf_gen; | |
3156 | ref->nritems = 0; | |
3157 | ||
3158 | btrfs_sort_leaf_ref(ref); | |
3159 | ||
3160 | ret = btrfs_add_leaf_ref(root, ref, 0); | |
3161 | WARN_ON(ret); | |
3162 | btrfs_free_leaf_ref(root, ref); | |
3163 | } else { | |
3164 | WARN_ON(1); | |
3165 | } | |
3166 | } | |
3167 | next_key: | |
3168 | btrfs_release_path(root, path); | |
3169 | ||
3170 | if (other_key.objectid == inode->i_ino && | |
3171 | other_key.type == key.type && other_key.offset > key.offset) { | |
3172 | key.offset = other_key.offset; | |
3173 | cond_resched(); | |
3174 | goto again; | |
3175 | } | |
3176 | ret = 0; | |
3177 | out: | |
3178 | /* fixup any changes we've made to the path */ | |
3179 | path->lowest_level = 0; | |
3180 | path->keep_locks = 0; | |
3181 | btrfs_release_path(root, path); | |
3182 | return ret; | |
3183 | } | |
3184 | ||
3185 | #endif | |
3186 | ||
3187 | /* | |
3188 | * this can truncate away extent items, csum items and directory items. | |
3189 | * It starts at a high offset and removes keys until it can't find | |
3190 | * any higher than new_size | |
3191 | * | |
3192 | * csum items that cross the new i_size are truncated to the new size | |
3193 | * as well. | |
3194 | * | |
3195 | * min_type is the minimum key type to truncate down to. If set to 0, this | |
3196 | * will kill all the items on this inode, including the INODE_ITEM_KEY. | |
3197 | */ | |
3198 | int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans, | |
3199 | struct btrfs_root *root, | |
3200 | struct inode *inode, | |
3201 | u64 new_size, u32 min_type) | |
3202 | { | |
3203 | struct btrfs_path *path; | |
3204 | struct extent_buffer *leaf; | |
3205 | struct btrfs_file_extent_item *fi; | |
3206 | struct btrfs_key key; | |
3207 | struct btrfs_key found_key; | |
3208 | u64 extent_start = 0; | |
3209 | u64 extent_num_bytes = 0; | |
3210 | u64 extent_offset = 0; | |
3211 | u64 item_end = 0; | |
3212 | u64 mask = root->sectorsize - 1; | |
3213 | u32 found_type = (u8)-1; | |
3214 | int found_extent; | |
3215 | int del_item; | |
3216 | int pending_del_nr = 0; | |
3217 | int pending_del_slot = 0; | |
3218 | int extent_type = -1; | |
3219 | int encoding; | |
3220 | int ret; | |
3221 | int err = 0; | |
3222 | ||
3223 | BUG_ON(new_size > 0 && min_type != BTRFS_EXTENT_DATA_KEY); | |
3224 | ||
3225 | if (root->ref_cows || root == root->fs_info->tree_root) | |
3226 | btrfs_drop_extent_cache(inode, new_size & (~mask), (u64)-1, 0); | |
3227 | ||
3228 | path = btrfs_alloc_path(); | |
3229 | BUG_ON(!path); | |
3230 | path->reada = -1; | |
3231 | ||
3232 | key.objectid = inode->i_ino; | |
3233 | key.offset = (u64)-1; | |
3234 | key.type = (u8)-1; | |
3235 | ||
3236 | search_again: | |
3237 | path->leave_spinning = 1; | |
3238 | ret = btrfs_search_slot(trans, root, &key, path, -1, 1); | |
3239 | if (ret < 0) { | |
3240 | err = ret; | |
3241 | goto out; | |
3242 | } | |
3243 | ||
3244 | if (ret > 0) { | |
3245 | /* there are no items in the tree for us to truncate, we're | |
3246 | * done | |
3247 | */ | |
3248 | if (path->slots[0] == 0) | |
3249 | goto out; | |
3250 | path->slots[0]--; | |
3251 | } | |
3252 | ||
3253 | while (1) { | |
3254 | fi = NULL; | |
3255 | leaf = path->nodes[0]; | |
3256 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); | |
3257 | found_type = btrfs_key_type(&found_key); | |
3258 | encoding = 0; | |
3259 | ||
3260 | if (found_key.objectid != inode->i_ino) | |
3261 | break; | |
3262 | ||
3263 | if (found_type < min_type) | |
3264 | break; | |
3265 | ||
3266 | item_end = found_key.offset; | |
3267 | if (found_type == BTRFS_EXTENT_DATA_KEY) { | |
3268 | fi = btrfs_item_ptr(leaf, path->slots[0], | |
3269 | struct btrfs_file_extent_item); | |
3270 | extent_type = btrfs_file_extent_type(leaf, fi); | |
3271 | encoding = btrfs_file_extent_compression(leaf, fi); | |
3272 | encoding |= btrfs_file_extent_encryption(leaf, fi); | |
3273 | encoding |= btrfs_file_extent_other_encoding(leaf, fi); | |
3274 | ||
3275 | if (extent_type != BTRFS_FILE_EXTENT_INLINE) { | |
3276 | item_end += | |
3277 | btrfs_file_extent_num_bytes(leaf, fi); | |
3278 | } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) { | |
3279 | item_end += btrfs_file_extent_inline_len(leaf, | |
3280 | fi); | |
3281 | } | |
3282 | item_end--; | |
3283 | } | |
3284 | if (found_type > min_type) { | |
3285 | del_item = 1; | |
3286 | } else { | |
3287 | if (item_end < new_size) | |
3288 | break; | |
3289 | if (found_key.offset >= new_size) | |
3290 | del_item = 1; | |
3291 | else | |
3292 | del_item = 0; | |
3293 | } | |
3294 | found_extent = 0; | |
3295 | /* FIXME, shrink the extent if the ref count is only 1 */ | |
3296 | if (found_type != BTRFS_EXTENT_DATA_KEY) | |
3297 | goto delete; | |
3298 | ||
3299 | if (extent_type != BTRFS_FILE_EXTENT_INLINE) { | |
3300 | u64 num_dec; | |
3301 | extent_start = btrfs_file_extent_disk_bytenr(leaf, fi); | |
3302 | if (!del_item && !encoding) { | |
3303 | u64 orig_num_bytes = | |
3304 | btrfs_file_extent_num_bytes(leaf, fi); | |
3305 | extent_num_bytes = new_size - | |
3306 | found_key.offset + root->sectorsize - 1; | |
3307 | extent_num_bytes = extent_num_bytes & | |
3308 | ~((u64)root->sectorsize - 1); | |
3309 | btrfs_set_file_extent_num_bytes(leaf, fi, | |
3310 | extent_num_bytes); | |
3311 | num_dec = (orig_num_bytes - | |
3312 | extent_num_bytes); | |
3313 | if (root->ref_cows && extent_start != 0) | |
3314 | inode_sub_bytes(inode, num_dec); | |
3315 | btrfs_mark_buffer_dirty(leaf); | |
3316 | } else { | |
3317 | extent_num_bytes = | |
3318 | btrfs_file_extent_disk_num_bytes(leaf, | |
3319 | fi); | |
3320 | extent_offset = found_key.offset - | |
3321 | btrfs_file_extent_offset(leaf, fi); | |
3322 | ||
3323 | /* FIXME blocksize != 4096 */ | |
3324 | num_dec = btrfs_file_extent_num_bytes(leaf, fi); | |
3325 | if (extent_start != 0) { | |
3326 | found_extent = 1; | |
3327 | if (root->ref_cows) | |
3328 | inode_sub_bytes(inode, num_dec); | |
3329 | } | |
3330 | } | |
3331 | } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) { | |
3332 | /* | |
3333 | * we can't truncate inline items that have had | |
3334 | * special encodings | |
3335 | */ | |
3336 | if (!del_item && | |
3337 | btrfs_file_extent_compression(leaf, fi) == 0 && | |
3338 | btrfs_file_extent_encryption(leaf, fi) == 0 && | |
3339 | btrfs_file_extent_other_encoding(leaf, fi) == 0) { | |
3340 | u32 size = new_size - found_key.offset; | |
3341 | ||
3342 | if (root->ref_cows) { | |
3343 | inode_sub_bytes(inode, item_end + 1 - | |
3344 | new_size); | |
3345 | } | |
3346 | size = | |
3347 | btrfs_file_extent_calc_inline_size(size); | |
3348 | ret = btrfs_truncate_item(trans, root, path, | |
3349 | size, 1); | |
3350 | BUG_ON(ret); | |
3351 | } else if (root->ref_cows) { | |
3352 | inode_sub_bytes(inode, item_end + 1 - | |
3353 | found_key.offset); | |
3354 | } | |
3355 | } | |
3356 | delete: | |
3357 | if (del_item) { | |
3358 | if (!pending_del_nr) { | |
3359 | /* no pending yet, add ourselves */ | |
3360 | pending_del_slot = path->slots[0]; | |
3361 | pending_del_nr = 1; | |
3362 | } else if (pending_del_nr && | |
3363 | path->slots[0] + 1 == pending_del_slot) { | |
3364 | /* hop on the pending chunk */ | |
3365 | pending_del_nr++; | |
3366 | pending_del_slot = path->slots[0]; | |
3367 | } else { | |
3368 | BUG(); | |
3369 | } | |
3370 | } else { | |
3371 | break; | |
3372 | } | |
3373 | if (found_extent && (root->ref_cows || | |
3374 | root == root->fs_info->tree_root)) { | |
3375 | btrfs_set_path_blocking(path); | |
3376 | ret = btrfs_free_extent(trans, root, extent_start, | |
3377 | extent_num_bytes, 0, | |
3378 | btrfs_header_owner(leaf), | |
3379 | inode->i_ino, extent_offset); | |
3380 | BUG_ON(ret); | |
3381 | } | |
3382 | ||
3383 | if (found_type == BTRFS_INODE_ITEM_KEY) | |
3384 | break; | |
3385 | ||
3386 | if (path->slots[0] == 0 || | |
3387 | path->slots[0] != pending_del_slot) { | |
3388 | if (root->ref_cows) { | |
3389 | err = -EAGAIN; | |
3390 | goto out; | |
3391 | } | |
3392 | if (pending_del_nr) { | |
3393 | ret = btrfs_del_items(trans, root, path, | |
3394 | pending_del_slot, | |
3395 | pending_del_nr); | |
3396 | BUG_ON(ret); | |
3397 | pending_del_nr = 0; | |
3398 | } | |
3399 | btrfs_release_path(root, path); | |
3400 | goto search_again; | |
3401 | } else { | |
3402 | path->slots[0]--; | |
3403 | } | |
3404 | } | |
3405 | out: | |
3406 | if (pending_del_nr) { | |
3407 | ret = btrfs_del_items(trans, root, path, pending_del_slot, | |
3408 | pending_del_nr); | |
3409 | BUG_ON(ret); | |
3410 | } | |
3411 | btrfs_free_path(path); | |
3412 | return err; | |
3413 | } | |
3414 | ||
3415 | /* | |
3416 | * taken from block_truncate_page, but does cow as it zeros out | |
3417 | * any bytes left in the last page in the file. | |
3418 | */ | |
3419 | static int btrfs_truncate_page(struct address_space *mapping, loff_t from) | |
3420 | { | |
3421 | struct inode *inode = mapping->host; | |
3422 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
3423 | struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; | |
3424 | struct btrfs_ordered_extent *ordered; | |
3425 | struct extent_state *cached_state = NULL; | |
3426 | char *kaddr; | |
3427 | u32 blocksize = root->sectorsize; | |
3428 | pgoff_t index = from >> PAGE_CACHE_SHIFT; | |
3429 | unsigned offset = from & (PAGE_CACHE_SIZE-1); | |
3430 | struct page *page; | |
3431 | int ret = 0; | |
3432 | u64 page_start; | |
3433 | u64 page_end; | |
3434 | ||
3435 | if ((offset & (blocksize - 1)) == 0) | |
3436 | goto out; | |
3437 | ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE); | |
3438 | if (ret) | |
3439 | goto out; | |
3440 | ||
3441 | ret = -ENOMEM; | |
3442 | again: | |
3443 | page = grab_cache_page(mapping, index); | |
3444 | if (!page) { | |
3445 | btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE); | |
3446 | goto out; | |
3447 | } | |
3448 | ||
3449 | page_start = page_offset(page); | |
3450 | page_end = page_start + PAGE_CACHE_SIZE - 1; | |
3451 | ||
3452 | if (!PageUptodate(page)) { | |
3453 | ret = btrfs_readpage(NULL, page); | |
3454 | lock_page(page); | |
3455 | if (page->mapping != mapping) { | |
3456 | unlock_page(page); | |
3457 | page_cache_release(page); | |
3458 | goto again; | |
3459 | } | |
3460 | if (!PageUptodate(page)) { | |
3461 | ret = -EIO; | |
3462 | goto out_unlock; | |
3463 | } | |
3464 | } | |
3465 | wait_on_page_writeback(page); | |
3466 | ||
3467 | lock_extent_bits(io_tree, page_start, page_end, 0, &cached_state, | |
3468 | GFP_NOFS); | |
3469 | set_page_extent_mapped(page); | |
3470 | ||
3471 | ordered = btrfs_lookup_ordered_extent(inode, page_start); | |
3472 | if (ordered) { | |
3473 | unlock_extent_cached(io_tree, page_start, page_end, | |
3474 | &cached_state, GFP_NOFS); | |
3475 | unlock_page(page); | |
3476 | page_cache_release(page); | |
3477 | btrfs_start_ordered_extent(inode, ordered, 1); | |
3478 | btrfs_put_ordered_extent(ordered); | |
3479 | goto again; | |
3480 | } | |
3481 | ||
3482 | clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, page_end, | |
3483 | EXTENT_DIRTY | EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING, | |
3484 | 0, 0, &cached_state, GFP_NOFS); | |
3485 | ||
3486 | ret = btrfs_set_extent_delalloc(inode, page_start, page_end, | |
3487 | &cached_state); | |
3488 | if (ret) { | |
3489 | unlock_extent_cached(io_tree, page_start, page_end, | |
3490 | &cached_state, GFP_NOFS); | |
3491 | goto out_unlock; | |
3492 | } | |
3493 | ||
3494 | ret = 0; | |
3495 | if (offset != PAGE_CACHE_SIZE) { | |
3496 | kaddr = kmap(page); | |
3497 | memset(kaddr + offset, 0, PAGE_CACHE_SIZE - offset); | |
3498 | flush_dcache_page(page); | |
3499 | kunmap(page); | |
3500 | } | |
3501 | ClearPageChecked(page); | |
3502 | set_page_dirty(page); | |
3503 | unlock_extent_cached(io_tree, page_start, page_end, &cached_state, | |
3504 | GFP_NOFS); | |
3505 | ||
3506 | out_unlock: | |
3507 | if (ret) | |
3508 | btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE); | |
3509 | unlock_page(page); | |
3510 | page_cache_release(page); | |
3511 | out: | |
3512 | return ret; | |
3513 | } | |
3514 | ||
3515 | int btrfs_cont_expand(struct inode *inode, loff_t size) | |
3516 | { | |
3517 | struct btrfs_trans_handle *trans; | |
3518 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
3519 | struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; | |
3520 | struct extent_map *em = NULL; | |
3521 | struct extent_state *cached_state = NULL; | |
3522 | u64 mask = root->sectorsize - 1; | |
3523 | u64 hole_start = (inode->i_size + mask) & ~mask; | |
3524 | u64 block_end = (size + mask) & ~mask; | |
3525 | u64 last_byte; | |
3526 | u64 cur_offset; | |
3527 | u64 hole_size; | |
3528 | int err = 0; | |
3529 | ||
3530 | if (size <= hole_start) | |
3531 | return 0; | |
3532 | ||
3533 | while (1) { | |
3534 | struct btrfs_ordered_extent *ordered; | |
3535 | btrfs_wait_ordered_range(inode, hole_start, | |
3536 | block_end - hole_start); | |
3537 | lock_extent_bits(io_tree, hole_start, block_end - 1, 0, | |
3538 | &cached_state, GFP_NOFS); | |
3539 | ordered = btrfs_lookup_ordered_extent(inode, hole_start); | |
3540 | if (!ordered) | |
3541 | break; | |
3542 | unlock_extent_cached(io_tree, hole_start, block_end - 1, | |
3543 | &cached_state, GFP_NOFS); | |
3544 | btrfs_put_ordered_extent(ordered); | |
3545 | } | |
3546 | ||
3547 | cur_offset = hole_start; | |
3548 | while (1) { | |
3549 | em = btrfs_get_extent(inode, NULL, 0, cur_offset, | |
3550 | block_end - cur_offset, 0); | |
3551 | BUG_ON(IS_ERR(em) || !em); | |
3552 | last_byte = min(extent_map_end(em), block_end); | |
3553 | last_byte = (last_byte + mask) & ~mask; | |
3554 | if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) { | |
3555 | u64 hint_byte = 0; | |
3556 | hole_size = last_byte - cur_offset; | |
3557 | ||
3558 | trans = btrfs_start_transaction(root, 2); | |
3559 | if (IS_ERR(trans)) { | |
3560 | err = PTR_ERR(trans); | |
3561 | break; | |
3562 | } | |
3563 | btrfs_set_trans_block_group(trans, inode); | |
3564 | ||
3565 | err = btrfs_drop_extents(trans, inode, cur_offset, | |
3566 | cur_offset + hole_size, | |
3567 | &hint_byte, 1); | |
3568 | BUG_ON(err); | |
3569 | ||
3570 | err = btrfs_insert_file_extent(trans, root, | |
3571 | inode->i_ino, cur_offset, 0, | |
3572 | 0, hole_size, 0, hole_size, | |
3573 | 0, 0, 0); | |
3574 | BUG_ON(err); | |
3575 | ||
3576 | btrfs_drop_extent_cache(inode, hole_start, | |
3577 | last_byte - 1, 0); | |
3578 | ||
3579 | btrfs_end_transaction(trans, root); | |
3580 | } | |
3581 | free_extent_map(em); | |
3582 | em = NULL; | |
3583 | cur_offset = last_byte; | |
3584 | if (cur_offset >= block_end) | |
3585 | break; | |
3586 | } | |
3587 | ||
3588 | free_extent_map(em); | |
3589 | unlock_extent_cached(io_tree, hole_start, block_end - 1, &cached_state, | |
3590 | GFP_NOFS); | |
3591 | return err; | |
3592 | } | |
3593 | ||
3594 | static int btrfs_setattr_size(struct inode *inode, struct iattr *attr) | |
3595 | { | |
3596 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
3597 | struct btrfs_trans_handle *trans; | |
3598 | unsigned long nr; | |
3599 | int ret; | |
3600 | ||
3601 | if (attr->ia_size == inode->i_size) | |
3602 | return 0; | |
3603 | ||
3604 | if (attr->ia_size > inode->i_size) { | |
3605 | unsigned long limit; | |
3606 | limit = current->signal->rlim[RLIMIT_FSIZE].rlim_cur; | |
3607 | if (attr->ia_size > inode->i_sb->s_maxbytes) | |
3608 | return -EFBIG; | |
3609 | if (limit != RLIM_INFINITY && attr->ia_size > limit) { | |
3610 | send_sig(SIGXFSZ, current, 0); | |
3611 | return -EFBIG; | |
3612 | } | |
3613 | } | |
3614 | ||
3615 | trans = btrfs_start_transaction(root, 5); | |
3616 | if (IS_ERR(trans)) | |
3617 | return PTR_ERR(trans); | |
3618 | ||
3619 | btrfs_set_trans_block_group(trans, inode); | |
3620 | ||
3621 | ret = btrfs_orphan_add(trans, inode); | |
3622 | BUG_ON(ret); | |
3623 | ||
3624 | nr = trans->blocks_used; | |
3625 | btrfs_end_transaction(trans, root); | |
3626 | btrfs_btree_balance_dirty(root, nr); | |
3627 | ||
3628 | if (attr->ia_size > inode->i_size) { | |
3629 | ret = btrfs_cont_expand(inode, attr->ia_size); | |
3630 | if (ret) { | |
3631 | btrfs_truncate(inode); | |
3632 | return ret; | |
3633 | } | |
3634 | ||
3635 | i_size_write(inode, attr->ia_size); | |
3636 | btrfs_ordered_update_i_size(inode, inode->i_size, NULL); | |
3637 | ||
3638 | trans = btrfs_start_transaction(root, 0); | |
3639 | BUG_ON(IS_ERR(trans)); | |
3640 | btrfs_set_trans_block_group(trans, inode); | |
3641 | trans->block_rsv = root->orphan_block_rsv; | |
3642 | BUG_ON(!trans->block_rsv); | |
3643 | ||
3644 | ret = btrfs_update_inode(trans, root, inode); | |
3645 | BUG_ON(ret); | |
3646 | if (inode->i_nlink > 0) { | |
3647 | ret = btrfs_orphan_del(trans, inode); | |
3648 | BUG_ON(ret); | |
3649 | } | |
3650 | nr = trans->blocks_used; | |
3651 | btrfs_end_transaction(trans, root); | |
3652 | btrfs_btree_balance_dirty(root, nr); | |
3653 | return 0; | |
3654 | } | |
3655 | ||
3656 | /* | |
3657 | * We're truncating a file that used to have good data down to | |
3658 | * zero. Make sure it gets into the ordered flush list so that | |
3659 | * any new writes get down to disk quickly. | |
3660 | */ | |
3661 | if (attr->ia_size == 0) | |
3662 | BTRFS_I(inode)->ordered_data_close = 1; | |
3663 | ||
3664 | /* we don't support swapfiles, so vmtruncate shouldn't fail */ | |
3665 | ret = vmtruncate(inode, attr->ia_size); | |
3666 | BUG_ON(ret); | |
3667 | ||
3668 | return 0; | |
3669 | } | |
3670 | ||
3671 | static int btrfs_setattr(struct dentry *dentry, struct iattr *attr) | |
3672 | { | |
3673 | struct inode *inode = dentry->d_inode; | |
3674 | int err; | |
3675 | ||
3676 | err = inode_change_ok(inode, attr); | |
3677 | if (err) | |
3678 | return err; | |
3679 | ||
3680 | if (S_ISREG(inode->i_mode) && (attr->ia_valid & ATTR_SIZE)) { | |
3681 | err = btrfs_setattr_size(inode, attr); | |
3682 | if (err) | |
3683 | return err; | |
3684 | } | |
3685 | ||
3686 | if (attr->ia_valid) { | |
3687 | setattr_copy(inode, attr); | |
3688 | mark_inode_dirty(inode); | |
3689 | ||
3690 | if (attr->ia_valid & ATTR_MODE) | |
3691 | err = btrfs_acl_chmod(inode); | |
3692 | } | |
3693 | ||
3694 | return err; | |
3695 | } | |
3696 | ||
3697 | void btrfs_evict_inode(struct inode *inode) | |
3698 | { | |
3699 | struct btrfs_trans_handle *trans; | |
3700 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
3701 | unsigned long nr; | |
3702 | int ret; | |
3703 | ||
3704 | truncate_inode_pages(&inode->i_data, 0); | |
3705 | if (inode->i_nlink && (btrfs_root_refs(&root->root_item) != 0 || | |
3706 | root == root->fs_info->tree_root)) | |
3707 | goto no_delete; | |
3708 | ||
3709 | if (is_bad_inode(inode)) { | |
3710 | btrfs_orphan_del(NULL, inode); | |
3711 | goto no_delete; | |
3712 | } | |
3713 | /* do we really want it for ->i_nlink > 0 and zero btrfs_root_refs? */ | |
3714 | btrfs_wait_ordered_range(inode, 0, (u64)-1); | |
3715 | ||
3716 | if (root->fs_info->log_root_recovering) { | |
3717 | BUG_ON(!list_empty(&BTRFS_I(inode)->i_orphan)); | |
3718 | goto no_delete; | |
3719 | } | |
3720 | ||
3721 | if (inode->i_nlink > 0) { | |
3722 | BUG_ON(btrfs_root_refs(&root->root_item) != 0); | |
3723 | goto no_delete; | |
3724 | } | |
3725 | ||
3726 | btrfs_i_size_write(inode, 0); | |
3727 | ||
3728 | while (1) { | |
3729 | trans = btrfs_start_transaction(root, 0); | |
3730 | BUG_ON(IS_ERR(trans)); | |
3731 | btrfs_set_trans_block_group(trans, inode); | |
3732 | trans->block_rsv = root->orphan_block_rsv; | |
3733 | ||
3734 | ret = btrfs_block_rsv_check(trans, root, | |
3735 | root->orphan_block_rsv, 0, 5); | |
3736 | if (ret) { | |
3737 | BUG_ON(ret != -EAGAIN); | |
3738 | ret = btrfs_commit_transaction(trans, root); | |
3739 | BUG_ON(ret); | |
3740 | continue; | |
3741 | } | |
3742 | ||
3743 | ret = btrfs_truncate_inode_items(trans, root, inode, 0, 0); | |
3744 | if (ret != -EAGAIN) | |
3745 | break; | |
3746 | ||
3747 | nr = trans->blocks_used; | |
3748 | btrfs_end_transaction(trans, root); | |
3749 | trans = NULL; | |
3750 | btrfs_btree_balance_dirty(root, nr); | |
3751 | ||
3752 | } | |
3753 | ||
3754 | if (ret == 0) { | |
3755 | ret = btrfs_orphan_del(trans, inode); | |
3756 | BUG_ON(ret); | |
3757 | } | |
3758 | ||
3759 | nr = trans->blocks_used; | |
3760 | btrfs_end_transaction(trans, root); | |
3761 | btrfs_btree_balance_dirty(root, nr); | |
3762 | no_delete: | |
3763 | end_writeback(inode); | |
3764 | return; | |
3765 | } | |
3766 | ||
3767 | /* | |
3768 | * this returns the key found in the dir entry in the location pointer. | |
3769 | * If no dir entries were found, location->objectid is 0. | |
3770 | */ | |
3771 | static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry, | |
3772 | struct btrfs_key *location) | |
3773 | { | |
3774 | const char *name = dentry->d_name.name; | |
3775 | int namelen = dentry->d_name.len; | |
3776 | struct btrfs_dir_item *di; | |
3777 | struct btrfs_path *path; | |
3778 | struct btrfs_root *root = BTRFS_I(dir)->root; | |
3779 | int ret = 0; | |
3780 | ||
3781 | path = btrfs_alloc_path(); | |
3782 | BUG_ON(!path); | |
3783 | ||
3784 | di = btrfs_lookup_dir_item(NULL, root, path, dir->i_ino, name, | |
3785 | namelen, 0); | |
3786 | if (IS_ERR(di)) | |
3787 | ret = PTR_ERR(di); | |
3788 | ||
3789 | if (!di || IS_ERR(di)) | |
3790 | goto out_err; | |
3791 | ||
3792 | btrfs_dir_item_key_to_cpu(path->nodes[0], di, location); | |
3793 | out: | |
3794 | btrfs_free_path(path); | |
3795 | return ret; | |
3796 | out_err: | |
3797 | location->objectid = 0; | |
3798 | goto out; | |
3799 | } | |
3800 | ||
3801 | /* | |
3802 | * when we hit a tree root in a directory, the btrfs part of the inode | |
3803 | * needs to be changed to reflect the root directory of the tree root. This | |
3804 | * is kind of like crossing a mount point. | |
3805 | */ | |
3806 | static int fixup_tree_root_location(struct btrfs_root *root, | |
3807 | struct inode *dir, | |
3808 | struct dentry *dentry, | |
3809 | struct btrfs_key *location, | |
3810 | struct btrfs_root **sub_root) | |
3811 | { | |
3812 | struct btrfs_path *path; | |
3813 | struct btrfs_root *new_root; | |
3814 | struct btrfs_root_ref *ref; | |
3815 | struct extent_buffer *leaf; | |
3816 | int ret; | |
3817 | int err = 0; | |
3818 | ||
3819 | path = btrfs_alloc_path(); | |
3820 | if (!path) { | |
3821 | err = -ENOMEM; | |
3822 | goto out; | |
3823 | } | |
3824 | ||
3825 | err = -ENOENT; | |
3826 | ret = btrfs_find_root_ref(root->fs_info->tree_root, path, | |
3827 | BTRFS_I(dir)->root->root_key.objectid, | |
3828 | location->objectid); | |
3829 | if (ret) { | |
3830 | if (ret < 0) | |
3831 | err = ret; | |
3832 | goto out; | |
3833 | } | |
3834 | ||
3835 | leaf = path->nodes[0]; | |
3836 | ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_ref); | |
3837 | if (btrfs_root_ref_dirid(leaf, ref) != dir->i_ino || | |
3838 | btrfs_root_ref_name_len(leaf, ref) != dentry->d_name.len) | |
3839 | goto out; | |
3840 | ||
3841 | ret = memcmp_extent_buffer(leaf, dentry->d_name.name, | |
3842 | (unsigned long)(ref + 1), | |
3843 | dentry->d_name.len); | |
3844 | if (ret) | |
3845 | goto out; | |
3846 | ||
3847 | btrfs_release_path(root->fs_info->tree_root, path); | |
3848 | ||
3849 | new_root = btrfs_read_fs_root_no_name(root->fs_info, location); | |
3850 | if (IS_ERR(new_root)) { | |
3851 | err = PTR_ERR(new_root); | |
3852 | goto out; | |
3853 | } | |
3854 | ||
3855 | if (btrfs_root_refs(&new_root->root_item) == 0) { | |
3856 | err = -ENOENT; | |
3857 | goto out; | |
3858 | } | |
3859 | ||
3860 | *sub_root = new_root; | |
3861 | location->objectid = btrfs_root_dirid(&new_root->root_item); | |
3862 | location->type = BTRFS_INODE_ITEM_KEY; | |
3863 | location->offset = 0; | |
3864 | err = 0; | |
3865 | out: | |
3866 | btrfs_free_path(path); | |
3867 | return err; | |
3868 | } | |
3869 | ||
3870 | static void inode_tree_add(struct inode *inode) | |
3871 | { | |
3872 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
3873 | struct btrfs_inode *entry; | |
3874 | struct rb_node **p; | |
3875 | struct rb_node *parent; | |
3876 | again: | |
3877 | p = &root->inode_tree.rb_node; | |
3878 | parent = NULL; | |
3879 | ||
3880 | if (hlist_unhashed(&inode->i_hash)) | |
3881 | return; | |
3882 | ||
3883 | spin_lock(&root->inode_lock); | |
3884 | while (*p) { | |
3885 | parent = *p; | |
3886 | entry = rb_entry(parent, struct btrfs_inode, rb_node); | |
3887 | ||
3888 | if (inode->i_ino < entry->vfs_inode.i_ino) | |
3889 | p = &parent->rb_left; | |
3890 | else if (inode->i_ino > entry->vfs_inode.i_ino) | |
3891 | p = &parent->rb_right; | |
3892 | else { | |
3893 | WARN_ON(!(entry->vfs_inode.i_state & | |
3894 | (I_WILL_FREE | I_FREEING))); | |
3895 | rb_erase(parent, &root->inode_tree); | |
3896 | RB_CLEAR_NODE(parent); | |
3897 | spin_unlock(&root->inode_lock); | |
3898 | goto again; | |
3899 | } | |
3900 | } | |
3901 | rb_link_node(&BTRFS_I(inode)->rb_node, parent, p); | |
3902 | rb_insert_color(&BTRFS_I(inode)->rb_node, &root->inode_tree); | |
3903 | spin_unlock(&root->inode_lock); | |
3904 | } | |
3905 | ||
3906 | static void inode_tree_del(struct inode *inode) | |
3907 | { | |
3908 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
3909 | int empty = 0; | |
3910 | ||
3911 | spin_lock(&root->inode_lock); | |
3912 | if (!RB_EMPTY_NODE(&BTRFS_I(inode)->rb_node)) { | |
3913 | rb_erase(&BTRFS_I(inode)->rb_node, &root->inode_tree); | |
3914 | RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node); | |
3915 | empty = RB_EMPTY_ROOT(&root->inode_tree); | |
3916 | } | |
3917 | spin_unlock(&root->inode_lock); | |
3918 | ||
3919 | /* | |
3920 | * Free space cache has inodes in the tree root, but the tree root has a | |
3921 | * root_refs of 0, so this could end up dropping the tree root as a | |
3922 | * snapshot, so we need the extra !root->fs_info->tree_root check to | |
3923 | * make sure we don't drop it. | |
3924 | */ | |
3925 | if (empty && btrfs_root_refs(&root->root_item) == 0 && | |
3926 | root != root->fs_info->tree_root) { | |
3927 | synchronize_srcu(&root->fs_info->subvol_srcu); | |
3928 | spin_lock(&root->inode_lock); | |
3929 | empty = RB_EMPTY_ROOT(&root->inode_tree); | |
3930 | spin_unlock(&root->inode_lock); | |
3931 | if (empty) | |
3932 | btrfs_add_dead_root(root); | |
3933 | } | |
3934 | } | |
3935 | ||
3936 | int btrfs_invalidate_inodes(struct btrfs_root *root) | |
3937 | { | |
3938 | struct rb_node *node; | |
3939 | struct rb_node *prev; | |
3940 | struct btrfs_inode *entry; | |
3941 | struct inode *inode; | |
3942 | u64 objectid = 0; | |
3943 | ||
3944 | WARN_ON(btrfs_root_refs(&root->root_item) != 0); | |
3945 | ||
3946 | spin_lock(&root->inode_lock); | |
3947 | again: | |
3948 | node = root->inode_tree.rb_node; | |
3949 | prev = NULL; | |
3950 | while (node) { | |
3951 | prev = node; | |
3952 | entry = rb_entry(node, struct btrfs_inode, rb_node); | |
3953 | ||
3954 | if (objectid < entry->vfs_inode.i_ino) | |
3955 | node = node->rb_left; | |
3956 | else if (objectid > entry->vfs_inode.i_ino) | |
3957 | node = node->rb_right; | |
3958 | else | |
3959 | break; | |
3960 | } | |
3961 | if (!node) { | |
3962 | while (prev) { | |
3963 | entry = rb_entry(prev, struct btrfs_inode, rb_node); | |
3964 | if (objectid <= entry->vfs_inode.i_ino) { | |
3965 | node = prev; | |
3966 | break; | |
3967 | } | |
3968 | prev = rb_next(prev); | |
3969 | } | |
3970 | } | |
3971 | while (node) { | |
3972 | entry = rb_entry(node, struct btrfs_inode, rb_node); | |
3973 | objectid = entry->vfs_inode.i_ino + 1; | |
3974 | inode = igrab(&entry->vfs_inode); | |
3975 | if (inode) { | |
3976 | spin_unlock(&root->inode_lock); | |
3977 | if (atomic_read(&inode->i_count) > 1) | |
3978 | d_prune_aliases(inode); | |
3979 | /* | |
3980 | * btrfs_drop_inode will have it removed from | |
3981 | * the inode cache when its usage count | |
3982 | * hits zero. | |
3983 | */ | |
3984 | iput(inode); | |
3985 | cond_resched(); | |
3986 | spin_lock(&root->inode_lock); | |
3987 | goto again; | |
3988 | } | |
3989 | ||
3990 | if (cond_resched_lock(&root->inode_lock)) | |
3991 | goto again; | |
3992 | ||
3993 | node = rb_next(node); | |
3994 | } | |
3995 | spin_unlock(&root->inode_lock); | |
3996 | return 0; | |
3997 | } | |
3998 | ||
3999 | static int btrfs_init_locked_inode(struct inode *inode, void *p) | |
4000 | { | |
4001 | struct btrfs_iget_args *args = p; | |
4002 | inode->i_ino = args->ino; | |
4003 | BTRFS_I(inode)->root = args->root; | |
4004 | btrfs_set_inode_space_info(args->root, inode); | |
4005 | return 0; | |
4006 | } | |
4007 | ||
4008 | static int btrfs_find_actor(struct inode *inode, void *opaque) | |
4009 | { | |
4010 | struct btrfs_iget_args *args = opaque; | |
4011 | return args->ino == inode->i_ino && | |
4012 | args->root == BTRFS_I(inode)->root; | |
4013 | } | |
4014 | ||
4015 | static struct inode *btrfs_iget_locked(struct super_block *s, | |
4016 | u64 objectid, | |
4017 | struct btrfs_root *root) | |
4018 | { | |
4019 | struct inode *inode; | |
4020 | struct btrfs_iget_args args; | |
4021 | args.ino = objectid; | |
4022 | args.root = root; | |
4023 | ||
4024 | inode = iget5_locked(s, objectid, btrfs_find_actor, | |
4025 | btrfs_init_locked_inode, | |
4026 | (void *)&args); | |
4027 | return inode; | |
4028 | } | |
4029 | ||
4030 | /* Get an inode object given its location and corresponding root. | |
4031 | * Returns in *is_new if the inode was read from disk | |
4032 | */ | |
4033 | struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location, | |
4034 | struct btrfs_root *root, int *new) | |
4035 | { | |
4036 | struct inode *inode; | |
4037 | ||
4038 | inode = btrfs_iget_locked(s, location->objectid, root); | |
4039 | if (!inode) | |
4040 | return ERR_PTR(-ENOMEM); | |
4041 | ||
4042 | if (inode->i_state & I_NEW) { | |
4043 | BTRFS_I(inode)->root = root; | |
4044 | memcpy(&BTRFS_I(inode)->location, location, sizeof(*location)); | |
4045 | btrfs_read_locked_inode(inode); | |
4046 | ||
4047 | inode_tree_add(inode); | |
4048 | unlock_new_inode(inode); | |
4049 | if (new) | |
4050 | *new = 1; | |
4051 | } | |
4052 | ||
4053 | return inode; | |
4054 | } | |
4055 | ||
4056 | static struct inode *new_simple_dir(struct super_block *s, | |
4057 | struct btrfs_key *key, | |
4058 | struct btrfs_root *root) | |
4059 | { | |
4060 | struct inode *inode = new_inode(s); | |
4061 | ||
4062 | if (!inode) | |
4063 | return ERR_PTR(-ENOMEM); | |
4064 | ||
4065 | BTRFS_I(inode)->root = root; | |
4066 | memcpy(&BTRFS_I(inode)->location, key, sizeof(*key)); | |
4067 | BTRFS_I(inode)->dummy_inode = 1; | |
4068 | ||
4069 | inode->i_ino = BTRFS_EMPTY_SUBVOL_DIR_OBJECTID; | |
4070 | inode->i_op = &simple_dir_inode_operations; | |
4071 | inode->i_fop = &simple_dir_operations; | |
4072 | inode->i_mode = S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO; | |
4073 | inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; | |
4074 | ||
4075 | return inode; | |
4076 | } | |
4077 | ||
4078 | struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry) | |
4079 | { | |
4080 | struct inode *inode; | |
4081 | struct btrfs_root *root = BTRFS_I(dir)->root; | |
4082 | struct btrfs_root *sub_root = root; | |
4083 | struct btrfs_key location; | |
4084 | int index; | |
4085 | int ret; | |
4086 | ||
4087 | dentry->d_op = &btrfs_dentry_operations; | |
4088 | ||
4089 | if (dentry->d_name.len > BTRFS_NAME_LEN) | |
4090 | return ERR_PTR(-ENAMETOOLONG); | |
4091 | ||
4092 | ret = btrfs_inode_by_name(dir, dentry, &location); | |
4093 | ||
4094 | if (ret < 0) | |
4095 | return ERR_PTR(ret); | |
4096 | ||
4097 | if (location.objectid == 0) | |
4098 | return NULL; | |
4099 | ||
4100 | if (location.type == BTRFS_INODE_ITEM_KEY) { | |
4101 | inode = btrfs_iget(dir->i_sb, &location, root, NULL); | |
4102 | return inode; | |
4103 | } | |
4104 | ||
4105 | BUG_ON(location.type != BTRFS_ROOT_ITEM_KEY); | |
4106 | ||
4107 | index = srcu_read_lock(&root->fs_info->subvol_srcu); | |
4108 | ret = fixup_tree_root_location(root, dir, dentry, | |
4109 | &location, &sub_root); | |
4110 | if (ret < 0) { | |
4111 | if (ret != -ENOENT) | |
4112 | inode = ERR_PTR(ret); | |
4113 | else | |
4114 | inode = new_simple_dir(dir->i_sb, &location, sub_root); | |
4115 | } else { | |
4116 | inode = btrfs_iget(dir->i_sb, &location, sub_root, NULL); | |
4117 | } | |
4118 | srcu_read_unlock(&root->fs_info->subvol_srcu, index); | |
4119 | ||
4120 | if (root != sub_root) { | |
4121 | down_read(&root->fs_info->cleanup_work_sem); | |
4122 | if (!(inode->i_sb->s_flags & MS_RDONLY)) | |
4123 | btrfs_orphan_cleanup(sub_root); | |
4124 | up_read(&root->fs_info->cleanup_work_sem); | |
4125 | } | |
4126 | ||
4127 | return inode; | |
4128 | } | |
4129 | ||
4130 | static int btrfs_dentry_delete(struct dentry *dentry) | |
4131 | { | |
4132 | struct btrfs_root *root; | |
4133 | ||
4134 | if (!dentry->d_inode && !IS_ROOT(dentry)) | |
4135 | dentry = dentry->d_parent; | |
4136 | ||
4137 | if (dentry->d_inode) { | |
4138 | root = BTRFS_I(dentry->d_inode)->root; | |
4139 | if (btrfs_root_refs(&root->root_item) == 0) | |
4140 | return 1; | |
4141 | } | |
4142 | return 0; | |
4143 | } | |
4144 | ||
4145 | static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry, | |
4146 | struct nameidata *nd) | |
4147 | { | |
4148 | struct inode *inode; | |
4149 | ||
4150 | inode = btrfs_lookup_dentry(dir, dentry); | |
4151 | if (IS_ERR(inode)) | |
4152 | return ERR_CAST(inode); | |
4153 | ||
4154 | return d_splice_alias(inode, dentry); | |
4155 | } | |
4156 | ||
4157 | static unsigned char btrfs_filetype_table[] = { | |
4158 | DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK | |
4159 | }; | |
4160 | ||
4161 | static int btrfs_real_readdir(struct file *filp, void *dirent, | |
4162 | filldir_t filldir) | |
4163 | { | |
4164 | struct inode *inode = filp->f_dentry->d_inode; | |
4165 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
4166 | struct btrfs_item *item; | |
4167 | struct btrfs_dir_item *di; | |
4168 | struct btrfs_key key; | |
4169 | struct btrfs_key found_key; | |
4170 | struct btrfs_path *path; | |
4171 | int ret; | |
4172 | u32 nritems; | |
4173 | struct extent_buffer *leaf; | |
4174 | int slot; | |
4175 | int advance; | |
4176 | unsigned char d_type; | |
4177 | int over = 0; | |
4178 | u32 di_cur; | |
4179 | u32 di_total; | |
4180 | u32 di_len; | |
4181 | int key_type = BTRFS_DIR_INDEX_KEY; | |
4182 | char tmp_name[32]; | |
4183 | char *name_ptr; | |
4184 | int name_len; | |
4185 | ||
4186 | /* FIXME, use a real flag for deciding about the key type */ | |
4187 | if (root->fs_info->tree_root == root) | |
4188 | key_type = BTRFS_DIR_ITEM_KEY; | |
4189 | ||
4190 | /* special case for "." */ | |
4191 | if (filp->f_pos == 0) { | |
4192 | over = filldir(dirent, ".", 1, | |
4193 | 1, inode->i_ino, | |
4194 | DT_DIR); | |
4195 | if (over) | |
4196 | return 0; | |
4197 | filp->f_pos = 1; | |
4198 | } | |
4199 | /* special case for .., just use the back ref */ | |
4200 | if (filp->f_pos == 1) { | |
4201 | u64 pino = parent_ino(filp->f_path.dentry); | |
4202 | over = filldir(dirent, "..", 2, | |
4203 | 2, pino, DT_DIR); | |
4204 | if (over) | |
4205 | return 0; | |
4206 | filp->f_pos = 2; | |
4207 | } | |
4208 | path = btrfs_alloc_path(); | |
4209 | path->reada = 2; | |
4210 | ||
4211 | btrfs_set_key_type(&key, key_type); | |
4212 | key.offset = filp->f_pos; | |
4213 | key.objectid = inode->i_ino; | |
4214 | ||
4215 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); | |
4216 | if (ret < 0) | |
4217 | goto err; | |
4218 | advance = 0; | |
4219 | ||
4220 | while (1) { | |
4221 | leaf = path->nodes[0]; | |
4222 | nritems = btrfs_header_nritems(leaf); | |
4223 | slot = path->slots[0]; | |
4224 | if (advance || slot >= nritems) { | |
4225 | if (slot >= nritems - 1) { | |
4226 | ret = btrfs_next_leaf(root, path); | |
4227 | if (ret) | |
4228 | break; | |
4229 | leaf = path->nodes[0]; | |
4230 | nritems = btrfs_header_nritems(leaf); | |
4231 | slot = path->slots[0]; | |
4232 | } else { | |
4233 | slot++; | |
4234 | path->slots[0]++; | |
4235 | } | |
4236 | } | |
4237 | ||
4238 | advance = 1; | |
4239 | item = btrfs_item_nr(leaf, slot); | |
4240 | btrfs_item_key_to_cpu(leaf, &found_key, slot); | |
4241 | ||
4242 | if (found_key.objectid != key.objectid) | |
4243 | break; | |
4244 | if (btrfs_key_type(&found_key) != key_type) | |
4245 | break; | |
4246 | if (found_key.offset < filp->f_pos) | |
4247 | continue; | |
4248 | ||
4249 | filp->f_pos = found_key.offset; | |
4250 | ||
4251 | di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item); | |
4252 | di_cur = 0; | |
4253 | di_total = btrfs_item_size(leaf, item); | |
4254 | ||
4255 | while (di_cur < di_total) { | |
4256 | struct btrfs_key location; | |
4257 | ||
4258 | name_len = btrfs_dir_name_len(leaf, di); | |
4259 | if (name_len <= sizeof(tmp_name)) { | |
4260 | name_ptr = tmp_name; | |
4261 | } else { | |
4262 | name_ptr = kmalloc(name_len, GFP_NOFS); | |
4263 | if (!name_ptr) { | |
4264 | ret = -ENOMEM; | |
4265 | goto err; | |
4266 | } | |
4267 | } | |
4268 | read_extent_buffer(leaf, name_ptr, | |
4269 | (unsigned long)(di + 1), name_len); | |
4270 | ||
4271 | d_type = btrfs_filetype_table[btrfs_dir_type(leaf, di)]; | |
4272 | btrfs_dir_item_key_to_cpu(leaf, di, &location); | |
4273 | ||
4274 | /* is this a reference to our own snapshot? If so | |
4275 | * skip it | |
4276 | */ | |
4277 | if (location.type == BTRFS_ROOT_ITEM_KEY && | |
4278 | location.objectid == root->root_key.objectid) { | |
4279 | over = 0; | |
4280 | goto skip; | |
4281 | } | |
4282 | over = filldir(dirent, name_ptr, name_len, | |
4283 | found_key.offset, location.objectid, | |
4284 | d_type); | |
4285 | ||
4286 | skip: | |
4287 | if (name_ptr != tmp_name) | |
4288 | kfree(name_ptr); | |
4289 | ||
4290 | if (over) | |
4291 | goto nopos; | |
4292 | di_len = btrfs_dir_name_len(leaf, di) + | |
4293 | btrfs_dir_data_len(leaf, di) + sizeof(*di); | |
4294 | di_cur += di_len; | |
4295 | di = (struct btrfs_dir_item *)((char *)di + di_len); | |
4296 | } | |
4297 | } | |
4298 | ||
4299 | /* Reached end of directory/root. Bump pos past the last item. */ | |
4300 | if (key_type == BTRFS_DIR_INDEX_KEY) | |
4301 | /* | |
4302 | * 32-bit glibc will use getdents64, but then strtol - | |
4303 | * so the last number we can serve is this. | |
4304 | */ | |
4305 | filp->f_pos = 0x7fffffff; | |
4306 | else | |
4307 | filp->f_pos++; | |
4308 | nopos: | |
4309 | ret = 0; | |
4310 | err: | |
4311 | btrfs_free_path(path); | |
4312 | return ret; | |
4313 | } | |
4314 | ||
4315 | int btrfs_write_inode(struct inode *inode, struct writeback_control *wbc) | |
4316 | { | |
4317 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
4318 | struct btrfs_trans_handle *trans; | |
4319 | int ret = 0; | |
4320 | bool nolock = false; | |
4321 | ||
4322 | if (BTRFS_I(inode)->dummy_inode) | |
4323 | return 0; | |
4324 | ||
4325 | smp_mb(); | |
4326 | nolock = (root->fs_info->closing && root == root->fs_info->tree_root); | |
4327 | ||
4328 | if (wbc->sync_mode == WB_SYNC_ALL) { | |
4329 | if (nolock) | |
4330 | trans = btrfs_join_transaction_nolock(root, 1); | |
4331 | else | |
4332 | trans = btrfs_join_transaction(root, 1); | |
4333 | btrfs_set_trans_block_group(trans, inode); | |
4334 | if (nolock) | |
4335 | ret = btrfs_end_transaction_nolock(trans, root); | |
4336 | else | |
4337 | ret = btrfs_commit_transaction(trans, root); | |
4338 | } | |
4339 | return ret; | |
4340 | } | |
4341 | ||
4342 | /* | |
4343 | * This is somewhat expensive, updating the tree every time the | |
4344 | * inode changes. But, it is most likely to find the inode in cache. | |
4345 | * FIXME, needs more benchmarking...there are no reasons other than performance | |
4346 | * to keep or drop this code. | |
4347 | */ | |
4348 | void btrfs_dirty_inode(struct inode *inode) | |
4349 | { | |
4350 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
4351 | struct btrfs_trans_handle *trans; | |
4352 | int ret; | |
4353 | ||
4354 | if (BTRFS_I(inode)->dummy_inode) | |
4355 | return; | |
4356 | ||
4357 | trans = btrfs_join_transaction(root, 1); | |
4358 | btrfs_set_trans_block_group(trans, inode); | |
4359 | ||
4360 | ret = btrfs_update_inode(trans, root, inode); | |
4361 | if (ret && ret == -ENOSPC) { | |
4362 | /* whoops, lets try again with the full transaction */ | |
4363 | btrfs_end_transaction(trans, root); | |
4364 | trans = btrfs_start_transaction(root, 1); | |
4365 | if (IS_ERR(trans)) { | |
4366 | if (printk_ratelimit()) { | |
4367 | printk(KERN_ERR "btrfs: fail to " | |
4368 | "dirty inode %lu error %ld\n", | |
4369 | inode->i_ino, PTR_ERR(trans)); | |
4370 | } | |
4371 | return; | |
4372 | } | |
4373 | btrfs_set_trans_block_group(trans, inode); | |
4374 | ||
4375 | ret = btrfs_update_inode(trans, root, inode); | |
4376 | if (ret) { | |
4377 | if (printk_ratelimit()) { | |
4378 | printk(KERN_ERR "btrfs: fail to " | |
4379 | "dirty inode %lu error %d\n", | |
4380 | inode->i_ino, ret); | |
4381 | } | |
4382 | } | |
4383 | } | |
4384 | btrfs_end_transaction(trans, root); | |
4385 | } | |
4386 | ||
4387 | /* | |
4388 | * find the highest existing sequence number in a directory | |
4389 | * and then set the in-memory index_cnt variable to reflect | |
4390 | * free sequence numbers | |
4391 | */ | |
4392 | static int btrfs_set_inode_index_count(struct inode *inode) | |
4393 | { | |
4394 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
4395 | struct btrfs_key key, found_key; | |
4396 | struct btrfs_path *path; | |
4397 | struct extent_buffer *leaf; | |
4398 | int ret; | |
4399 | ||
4400 | key.objectid = inode->i_ino; | |
4401 | btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY); | |
4402 | key.offset = (u64)-1; | |
4403 | ||
4404 | path = btrfs_alloc_path(); | |
4405 | if (!path) | |
4406 | return -ENOMEM; | |
4407 | ||
4408 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); | |
4409 | if (ret < 0) | |
4410 | goto out; | |
4411 | /* FIXME: we should be able to handle this */ | |
4412 | if (ret == 0) | |
4413 | goto out; | |
4414 | ret = 0; | |
4415 | ||
4416 | /* | |
4417 | * MAGIC NUMBER EXPLANATION: | |
4418 | * since we search a directory based on f_pos we have to start at 2 | |
4419 | * since '.' and '..' have f_pos of 0 and 1 respectively, so everybody | |
4420 | * else has to start at 2 | |
4421 | */ | |
4422 | if (path->slots[0] == 0) { | |
4423 | BTRFS_I(inode)->index_cnt = 2; | |
4424 | goto out; | |
4425 | } | |
4426 | ||
4427 | path->slots[0]--; | |
4428 | ||
4429 | leaf = path->nodes[0]; | |
4430 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); | |
4431 | ||
4432 | if (found_key.objectid != inode->i_ino || | |
4433 | btrfs_key_type(&found_key) != BTRFS_DIR_INDEX_KEY) { | |
4434 | BTRFS_I(inode)->index_cnt = 2; | |
4435 | goto out; | |
4436 | } | |
4437 | ||
4438 | BTRFS_I(inode)->index_cnt = found_key.offset + 1; | |
4439 | out: | |
4440 | btrfs_free_path(path); | |
4441 | return ret; | |
4442 | } | |
4443 | ||
4444 | /* | |
4445 | * helper to find a free sequence number in a given directory. This current | |
4446 | * code is very simple, later versions will do smarter things in the btree | |
4447 | */ | |
4448 | int btrfs_set_inode_index(struct inode *dir, u64 *index) | |
4449 | { | |
4450 | int ret = 0; | |
4451 | ||
4452 | if (BTRFS_I(dir)->index_cnt == (u64)-1) { | |
4453 | ret = btrfs_set_inode_index_count(dir); | |
4454 | if (ret) | |
4455 | return ret; | |
4456 | } | |
4457 | ||
4458 | *index = BTRFS_I(dir)->index_cnt; | |
4459 | BTRFS_I(dir)->index_cnt++; | |
4460 | ||
4461 | return ret; | |
4462 | } | |
4463 | ||
4464 | static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans, | |
4465 | struct btrfs_root *root, | |
4466 | struct inode *dir, | |
4467 | const char *name, int name_len, | |
4468 | u64 ref_objectid, u64 objectid, | |
4469 | u64 alloc_hint, int mode, u64 *index) | |
4470 | { | |
4471 | struct inode *inode; | |
4472 | struct btrfs_inode_item *inode_item; | |
4473 | struct btrfs_key *location; | |
4474 | struct btrfs_path *path; | |
4475 | struct btrfs_inode_ref *ref; | |
4476 | struct btrfs_key key[2]; | |
4477 | u32 sizes[2]; | |
4478 | unsigned long ptr; | |
4479 | int ret; | |
4480 | int owner; | |
4481 | ||
4482 | path = btrfs_alloc_path(); | |
4483 | BUG_ON(!path); | |
4484 | ||
4485 | inode = new_inode(root->fs_info->sb); | |
4486 | if (!inode) | |
4487 | return ERR_PTR(-ENOMEM); | |
4488 | ||
4489 | if (dir) { | |
4490 | ret = btrfs_set_inode_index(dir, index); | |
4491 | if (ret) { | |
4492 | iput(inode); | |
4493 | return ERR_PTR(ret); | |
4494 | } | |
4495 | } | |
4496 | /* | |
4497 | * index_cnt is ignored for everything but a dir, | |
4498 | * btrfs_get_inode_index_count has an explanation for the magic | |
4499 | * number | |
4500 | */ | |
4501 | BTRFS_I(inode)->index_cnt = 2; | |
4502 | BTRFS_I(inode)->root = root; | |
4503 | BTRFS_I(inode)->generation = trans->transid; | |
4504 | inode->i_generation = BTRFS_I(inode)->generation; | |
4505 | btrfs_set_inode_space_info(root, inode); | |
4506 | ||
4507 | if (mode & S_IFDIR) | |
4508 | owner = 0; | |
4509 | else | |
4510 | owner = 1; | |
4511 | BTRFS_I(inode)->block_group = | |
4512 | btrfs_find_block_group(root, 0, alloc_hint, owner); | |
4513 | ||
4514 | key[0].objectid = objectid; | |
4515 | btrfs_set_key_type(&key[0], BTRFS_INODE_ITEM_KEY); | |
4516 | key[0].offset = 0; | |
4517 | ||
4518 | key[1].objectid = objectid; | |
4519 | btrfs_set_key_type(&key[1], BTRFS_INODE_REF_KEY); | |
4520 | key[1].offset = ref_objectid; | |
4521 | ||
4522 | sizes[0] = sizeof(struct btrfs_inode_item); | |
4523 | sizes[1] = name_len + sizeof(*ref); | |
4524 | ||
4525 | path->leave_spinning = 1; | |
4526 | ret = btrfs_insert_empty_items(trans, root, path, key, sizes, 2); | |
4527 | if (ret != 0) | |
4528 | goto fail; | |
4529 | ||
4530 | inode_init_owner(inode, dir, mode); | |
4531 | inode->i_ino = objectid; | |
4532 | inode_set_bytes(inode, 0); | |
4533 | inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; | |
4534 | inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0], | |
4535 | struct btrfs_inode_item); | |
4536 | fill_inode_item(trans, path->nodes[0], inode_item, inode); | |
4537 | ||
4538 | ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1, | |
4539 | struct btrfs_inode_ref); | |
4540 | btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len); | |
4541 | btrfs_set_inode_ref_index(path->nodes[0], ref, *index); | |
4542 | ptr = (unsigned long)(ref + 1); | |
4543 | write_extent_buffer(path->nodes[0], name, ptr, name_len); | |
4544 | ||
4545 | btrfs_mark_buffer_dirty(path->nodes[0]); | |
4546 | btrfs_free_path(path); | |
4547 | ||
4548 | location = &BTRFS_I(inode)->location; | |
4549 | location->objectid = objectid; | |
4550 | location->offset = 0; | |
4551 | btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY); | |
4552 | ||
4553 | btrfs_inherit_iflags(inode, dir); | |
4554 | ||
4555 | if ((mode & S_IFREG)) { | |
4556 | if (btrfs_test_opt(root, NODATASUM)) | |
4557 | BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM; | |
4558 | if (btrfs_test_opt(root, NODATACOW)) | |
4559 | BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW; | |
4560 | } | |
4561 | ||
4562 | insert_inode_hash(inode); | |
4563 | inode_tree_add(inode); | |
4564 | return inode; | |
4565 | fail: | |
4566 | if (dir) | |
4567 | BTRFS_I(dir)->index_cnt--; | |
4568 | btrfs_free_path(path); | |
4569 | iput(inode); | |
4570 | return ERR_PTR(ret); | |
4571 | } | |
4572 | ||
4573 | static inline u8 btrfs_inode_type(struct inode *inode) | |
4574 | { | |
4575 | return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT]; | |
4576 | } | |
4577 | ||
4578 | /* | |
4579 | * utility function to add 'inode' into 'parent_inode' with | |
4580 | * a give name and a given sequence number. | |
4581 | * if 'add_backref' is true, also insert a backref from the | |
4582 | * inode to the parent directory. | |
4583 | */ | |
4584 | int btrfs_add_link(struct btrfs_trans_handle *trans, | |
4585 | struct inode *parent_inode, struct inode *inode, | |
4586 | const char *name, int name_len, int add_backref, u64 index) | |
4587 | { | |
4588 | int ret = 0; | |
4589 | struct btrfs_key key; | |
4590 | struct btrfs_root *root = BTRFS_I(parent_inode)->root; | |
4591 | ||
4592 | if (unlikely(inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)) { | |
4593 | memcpy(&key, &BTRFS_I(inode)->root->root_key, sizeof(key)); | |
4594 | } else { | |
4595 | key.objectid = inode->i_ino; | |
4596 | btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY); | |
4597 | key.offset = 0; | |
4598 | } | |
4599 | ||
4600 | if (unlikely(inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)) { | |
4601 | ret = btrfs_add_root_ref(trans, root->fs_info->tree_root, | |
4602 | key.objectid, root->root_key.objectid, | |
4603 | parent_inode->i_ino, | |
4604 | index, name, name_len); | |
4605 | } else if (add_backref) { | |
4606 | ret = btrfs_insert_inode_ref(trans, root, | |
4607 | name, name_len, inode->i_ino, | |
4608 | parent_inode->i_ino, index); | |
4609 | } | |
4610 | ||
4611 | if (ret == 0) { | |
4612 | ret = btrfs_insert_dir_item(trans, root, name, name_len, | |
4613 | parent_inode->i_ino, &key, | |
4614 | btrfs_inode_type(inode), index); | |
4615 | BUG_ON(ret); | |
4616 | ||
4617 | btrfs_i_size_write(parent_inode, parent_inode->i_size + | |
4618 | name_len * 2); | |
4619 | parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME; | |
4620 | ret = btrfs_update_inode(trans, root, parent_inode); | |
4621 | } | |
4622 | return ret; | |
4623 | } | |
4624 | ||
4625 | static int btrfs_add_nondir(struct btrfs_trans_handle *trans, | |
4626 | struct dentry *dentry, struct inode *inode, | |
4627 | int backref, u64 index) | |
4628 | { | |
4629 | int err = btrfs_add_link(trans, dentry->d_parent->d_inode, | |
4630 | inode, dentry->d_name.name, | |
4631 | dentry->d_name.len, backref, index); | |
4632 | if (!err) { | |
4633 | d_instantiate(dentry, inode); | |
4634 | return 0; | |
4635 | } | |
4636 | if (err > 0) | |
4637 | err = -EEXIST; | |
4638 | return err; | |
4639 | } | |
4640 | ||
4641 | static int btrfs_mknod(struct inode *dir, struct dentry *dentry, | |
4642 | int mode, dev_t rdev) | |
4643 | { | |
4644 | struct btrfs_trans_handle *trans; | |
4645 | struct btrfs_root *root = BTRFS_I(dir)->root; | |
4646 | struct inode *inode = NULL; | |
4647 | int err; | |
4648 | int drop_inode = 0; | |
4649 | u64 objectid; | |
4650 | unsigned long nr = 0; | |
4651 | u64 index = 0; | |
4652 | ||
4653 | if (!new_valid_dev(rdev)) | |
4654 | return -EINVAL; | |
4655 | ||
4656 | err = btrfs_find_free_objectid(NULL, root, dir->i_ino, &objectid); | |
4657 | if (err) | |
4658 | return err; | |
4659 | ||
4660 | /* | |
4661 | * 2 for inode item and ref | |
4662 | * 2 for dir items | |
4663 | * 1 for xattr if selinux is on | |
4664 | */ | |
4665 | trans = btrfs_start_transaction(root, 5); | |
4666 | if (IS_ERR(trans)) | |
4667 | return PTR_ERR(trans); | |
4668 | ||
4669 | btrfs_set_trans_block_group(trans, dir); | |
4670 | ||
4671 | inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name, | |
4672 | dentry->d_name.len, | |
4673 | dentry->d_parent->d_inode->i_ino, objectid, | |
4674 | BTRFS_I(dir)->block_group, mode, &index); | |
4675 | err = PTR_ERR(inode); | |
4676 | if (IS_ERR(inode)) | |
4677 | goto out_unlock; | |
4678 | ||
4679 | err = btrfs_init_inode_security(trans, inode, dir); | |
4680 | if (err) { | |
4681 | drop_inode = 1; | |
4682 | goto out_unlock; | |
4683 | } | |
4684 | ||
4685 | btrfs_set_trans_block_group(trans, inode); | |
4686 | err = btrfs_add_nondir(trans, dentry, inode, 0, index); | |
4687 | if (err) | |
4688 | drop_inode = 1; | |
4689 | else { | |
4690 | inode->i_op = &btrfs_special_inode_operations; | |
4691 | init_special_inode(inode, inode->i_mode, rdev); | |
4692 | btrfs_update_inode(trans, root, inode); | |
4693 | } | |
4694 | btrfs_update_inode_block_group(trans, inode); | |
4695 | btrfs_update_inode_block_group(trans, dir); | |
4696 | out_unlock: | |
4697 | nr = trans->blocks_used; | |
4698 | btrfs_end_transaction_throttle(trans, root); | |
4699 | btrfs_btree_balance_dirty(root, nr); | |
4700 | if (drop_inode) { | |
4701 | inode_dec_link_count(inode); | |
4702 | iput(inode); | |
4703 | } | |
4704 | return err; | |
4705 | } | |
4706 | ||
4707 | static int btrfs_create(struct inode *dir, struct dentry *dentry, | |
4708 | int mode, struct nameidata *nd) | |
4709 | { | |
4710 | struct btrfs_trans_handle *trans; | |
4711 | struct btrfs_root *root = BTRFS_I(dir)->root; | |
4712 | struct inode *inode = NULL; | |
4713 | int drop_inode = 0; | |
4714 | int err; | |
4715 | unsigned long nr = 0; | |
4716 | u64 objectid; | |
4717 | u64 index = 0; | |
4718 | ||
4719 | err = btrfs_find_free_objectid(NULL, root, dir->i_ino, &objectid); | |
4720 | if (err) | |
4721 | return err; | |
4722 | /* | |
4723 | * 2 for inode item and ref | |
4724 | * 2 for dir items | |
4725 | * 1 for xattr if selinux is on | |
4726 | */ | |
4727 | trans = btrfs_start_transaction(root, 5); | |
4728 | if (IS_ERR(trans)) | |
4729 | return PTR_ERR(trans); | |
4730 | ||
4731 | btrfs_set_trans_block_group(trans, dir); | |
4732 | ||
4733 | inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name, | |
4734 | dentry->d_name.len, | |
4735 | dentry->d_parent->d_inode->i_ino, | |
4736 | objectid, BTRFS_I(dir)->block_group, mode, | |
4737 | &index); | |
4738 | err = PTR_ERR(inode); | |
4739 | if (IS_ERR(inode)) | |
4740 | goto out_unlock; | |
4741 | ||
4742 | err = btrfs_init_inode_security(trans, inode, dir); | |
4743 | if (err) { | |
4744 | drop_inode = 1; | |
4745 | goto out_unlock; | |
4746 | } | |
4747 | ||
4748 | btrfs_set_trans_block_group(trans, inode); | |
4749 | err = btrfs_add_nondir(trans, dentry, inode, 0, index); | |
4750 | if (err) | |
4751 | drop_inode = 1; | |
4752 | else { | |
4753 | inode->i_mapping->a_ops = &btrfs_aops; | |
4754 | inode->i_mapping->backing_dev_info = &root->fs_info->bdi; | |
4755 | inode->i_fop = &btrfs_file_operations; | |
4756 | inode->i_op = &btrfs_file_inode_operations; | |
4757 | BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; | |
4758 | } | |
4759 | btrfs_update_inode_block_group(trans, inode); | |
4760 | btrfs_update_inode_block_group(trans, dir); | |
4761 | out_unlock: | |
4762 | nr = trans->blocks_used; | |
4763 | btrfs_end_transaction_throttle(trans, root); | |
4764 | if (drop_inode) { | |
4765 | inode_dec_link_count(inode); | |
4766 | iput(inode); | |
4767 | } | |
4768 | btrfs_btree_balance_dirty(root, nr); | |
4769 | return err; | |
4770 | } | |
4771 | ||
4772 | static int btrfs_link(struct dentry *old_dentry, struct inode *dir, | |
4773 | struct dentry *dentry) | |
4774 | { | |
4775 | struct btrfs_trans_handle *trans; | |
4776 | struct btrfs_root *root = BTRFS_I(dir)->root; | |
4777 | struct inode *inode = old_dentry->d_inode; | |
4778 | u64 index; | |
4779 | unsigned long nr = 0; | |
4780 | int err; | |
4781 | int drop_inode = 0; | |
4782 | ||
4783 | if (inode->i_nlink == 0) | |
4784 | return -ENOENT; | |
4785 | ||
4786 | /* do not allow sys_link's with other subvols of the same device */ | |
4787 | if (root->objectid != BTRFS_I(inode)->root->objectid) | |
4788 | return -EPERM; | |
4789 | ||
4790 | btrfs_inc_nlink(inode); | |
4791 | ||
4792 | err = btrfs_set_inode_index(dir, &index); | |
4793 | if (err) | |
4794 | goto fail; | |
4795 | ||
4796 | /* | |
4797 | * 1 item for inode ref | |
4798 | * 2 items for dir items | |
4799 | */ | |
4800 | trans = btrfs_start_transaction(root, 3); | |
4801 | if (IS_ERR(trans)) { | |
4802 | err = PTR_ERR(trans); | |
4803 | goto fail; | |
4804 | } | |
4805 | ||
4806 | btrfs_set_trans_block_group(trans, dir); | |
4807 | atomic_inc(&inode->i_count); | |
4808 | ||
4809 | err = btrfs_add_nondir(trans, dentry, inode, 1, index); | |
4810 | ||
4811 | if (err) { | |
4812 | drop_inode = 1; | |
4813 | } else { | |
4814 | btrfs_update_inode_block_group(trans, dir); | |
4815 | err = btrfs_update_inode(trans, root, inode); | |
4816 | BUG_ON(err); | |
4817 | btrfs_log_new_name(trans, inode, NULL, dentry->d_parent); | |
4818 | } | |
4819 | ||
4820 | nr = trans->blocks_used; | |
4821 | btrfs_end_transaction_throttle(trans, root); | |
4822 | fail: | |
4823 | if (drop_inode) { | |
4824 | inode_dec_link_count(inode); | |
4825 | iput(inode); | |
4826 | } | |
4827 | btrfs_btree_balance_dirty(root, nr); | |
4828 | return err; | |
4829 | } | |
4830 | ||
4831 | static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode) | |
4832 | { | |
4833 | struct inode *inode = NULL; | |
4834 | struct btrfs_trans_handle *trans; | |
4835 | struct btrfs_root *root = BTRFS_I(dir)->root; | |
4836 | int err = 0; | |
4837 | int drop_on_err = 0; | |
4838 | u64 objectid = 0; | |
4839 | u64 index = 0; | |
4840 | unsigned long nr = 1; | |
4841 | ||
4842 | err = btrfs_find_free_objectid(NULL, root, dir->i_ino, &objectid); | |
4843 | if (err) | |
4844 | return err; | |
4845 | ||
4846 | /* | |
4847 | * 2 items for inode and ref | |
4848 | * 2 items for dir items | |
4849 | * 1 for xattr if selinux is on | |
4850 | */ | |
4851 | trans = btrfs_start_transaction(root, 5); | |
4852 | if (IS_ERR(trans)) | |
4853 | return PTR_ERR(trans); | |
4854 | btrfs_set_trans_block_group(trans, dir); | |
4855 | ||
4856 | inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name, | |
4857 | dentry->d_name.len, | |
4858 | dentry->d_parent->d_inode->i_ino, objectid, | |
4859 | BTRFS_I(dir)->block_group, S_IFDIR | mode, | |
4860 | &index); | |
4861 | if (IS_ERR(inode)) { | |
4862 | err = PTR_ERR(inode); | |
4863 | goto out_fail; | |
4864 | } | |
4865 | ||
4866 | drop_on_err = 1; | |
4867 | ||
4868 | err = btrfs_init_inode_security(trans, inode, dir); | |
4869 | if (err) | |
4870 | goto out_fail; | |
4871 | ||
4872 | inode->i_op = &btrfs_dir_inode_operations; | |
4873 | inode->i_fop = &btrfs_dir_file_operations; | |
4874 | btrfs_set_trans_block_group(trans, inode); | |
4875 | ||
4876 | btrfs_i_size_write(inode, 0); | |
4877 | err = btrfs_update_inode(trans, root, inode); | |
4878 | if (err) | |
4879 | goto out_fail; | |
4880 | ||
4881 | err = btrfs_add_link(trans, dentry->d_parent->d_inode, | |
4882 | inode, dentry->d_name.name, | |
4883 | dentry->d_name.len, 0, index); | |
4884 | if (err) | |
4885 | goto out_fail; | |
4886 | ||
4887 | d_instantiate(dentry, inode); | |
4888 | drop_on_err = 0; | |
4889 | btrfs_update_inode_block_group(trans, inode); | |
4890 | btrfs_update_inode_block_group(trans, dir); | |
4891 | ||
4892 | out_fail: | |
4893 | nr = trans->blocks_used; | |
4894 | btrfs_end_transaction_throttle(trans, root); | |
4895 | if (drop_on_err) | |
4896 | iput(inode); | |
4897 | btrfs_btree_balance_dirty(root, nr); | |
4898 | return err; | |
4899 | } | |
4900 | ||
4901 | /* helper for btfs_get_extent. Given an existing extent in the tree, | |
4902 | * and an extent that you want to insert, deal with overlap and insert | |
4903 | * the new extent into the tree. | |
4904 | */ | |
4905 | static int merge_extent_mapping(struct extent_map_tree *em_tree, | |
4906 | struct extent_map *existing, | |
4907 | struct extent_map *em, | |
4908 | u64 map_start, u64 map_len) | |
4909 | { | |
4910 | u64 start_diff; | |
4911 | ||
4912 | BUG_ON(map_start < em->start || map_start >= extent_map_end(em)); | |
4913 | start_diff = map_start - em->start; | |
4914 | em->start = map_start; | |
4915 | em->len = map_len; | |
4916 | if (em->block_start < EXTENT_MAP_LAST_BYTE && | |
4917 | !test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) { | |
4918 | em->block_start += start_diff; | |
4919 | em->block_len -= start_diff; | |
4920 | } | |
4921 | return add_extent_mapping(em_tree, em); | |
4922 | } | |
4923 | ||
4924 | static noinline int uncompress_inline(struct btrfs_path *path, | |
4925 | struct inode *inode, struct page *page, | |
4926 | size_t pg_offset, u64 extent_offset, | |
4927 | struct btrfs_file_extent_item *item) | |
4928 | { | |
4929 | int ret; | |
4930 | struct extent_buffer *leaf = path->nodes[0]; | |
4931 | char *tmp; | |
4932 | size_t max_size; | |
4933 | unsigned long inline_size; | |
4934 | unsigned long ptr; | |
4935 | ||
4936 | WARN_ON(pg_offset != 0); | |
4937 | max_size = btrfs_file_extent_ram_bytes(leaf, item); | |
4938 | inline_size = btrfs_file_extent_inline_item_len(leaf, | |
4939 | btrfs_item_nr(leaf, path->slots[0])); | |
4940 | tmp = kmalloc(inline_size, GFP_NOFS); | |
4941 | ptr = btrfs_file_extent_inline_start(item); | |
4942 | ||
4943 | read_extent_buffer(leaf, tmp, ptr, inline_size); | |
4944 | ||
4945 | max_size = min_t(unsigned long, PAGE_CACHE_SIZE, max_size); | |
4946 | ret = btrfs_zlib_decompress(tmp, page, extent_offset, | |
4947 | inline_size, max_size); | |
4948 | if (ret) { | |
4949 | char *kaddr = kmap_atomic(page, KM_USER0); | |
4950 | unsigned long copy_size = min_t(u64, | |
4951 | PAGE_CACHE_SIZE - pg_offset, | |
4952 | max_size - extent_offset); | |
4953 | memset(kaddr + pg_offset, 0, copy_size); | |
4954 | kunmap_atomic(kaddr, KM_USER0); | |
4955 | } | |
4956 | kfree(tmp); | |
4957 | return 0; | |
4958 | } | |
4959 | ||
4960 | /* | |
4961 | * a bit scary, this does extent mapping from logical file offset to the disk. | |
4962 | * the ugly parts come from merging extents from the disk with the in-ram | |
4963 | * representation. This gets more complex because of the data=ordered code, | |
4964 | * where the in-ram extents might be locked pending data=ordered completion. | |
4965 | * | |
4966 | * This also copies inline extents directly into the page. | |
4967 | */ | |
4968 | ||
4969 | struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page, | |
4970 | size_t pg_offset, u64 start, u64 len, | |
4971 | int create) | |
4972 | { | |
4973 | int ret; | |
4974 | int err = 0; | |
4975 | u64 bytenr; | |
4976 | u64 extent_start = 0; | |
4977 | u64 extent_end = 0; | |
4978 | u64 objectid = inode->i_ino; | |
4979 | u32 found_type; | |
4980 | struct btrfs_path *path = NULL; | |
4981 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
4982 | struct btrfs_file_extent_item *item; | |
4983 | struct extent_buffer *leaf; | |
4984 | struct btrfs_key found_key; | |
4985 | struct extent_map *em = NULL; | |
4986 | struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; | |
4987 | struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; | |
4988 | struct btrfs_trans_handle *trans = NULL; | |
4989 | int compressed; | |
4990 | ||
4991 | again: | |
4992 | read_lock(&em_tree->lock); | |
4993 | em = lookup_extent_mapping(em_tree, start, len); | |
4994 | if (em) | |
4995 | em->bdev = root->fs_info->fs_devices->latest_bdev; | |
4996 | read_unlock(&em_tree->lock); | |
4997 | ||
4998 | if (em) { | |
4999 | if (em->start > start || em->start + em->len <= start) | |
5000 | free_extent_map(em); | |
5001 | else if (em->block_start == EXTENT_MAP_INLINE && page) | |
5002 | free_extent_map(em); | |
5003 | else | |
5004 | goto out; | |
5005 | } | |
5006 | em = alloc_extent_map(GFP_NOFS); | |
5007 | if (!em) { | |
5008 | err = -ENOMEM; | |
5009 | goto out; | |
5010 | } | |
5011 | em->bdev = root->fs_info->fs_devices->latest_bdev; | |
5012 | em->start = EXTENT_MAP_HOLE; | |
5013 | em->orig_start = EXTENT_MAP_HOLE; | |
5014 | em->len = (u64)-1; | |
5015 | em->block_len = (u64)-1; | |
5016 | ||
5017 | if (!path) { | |
5018 | path = btrfs_alloc_path(); | |
5019 | BUG_ON(!path); | |
5020 | } | |
5021 | ||
5022 | ret = btrfs_lookup_file_extent(trans, root, path, | |
5023 | objectid, start, trans != NULL); | |
5024 | if (ret < 0) { | |
5025 | err = ret; | |
5026 | goto out; | |
5027 | } | |
5028 | ||
5029 | if (ret != 0) { | |
5030 | if (path->slots[0] == 0) | |
5031 | goto not_found; | |
5032 | path->slots[0]--; | |
5033 | } | |
5034 | ||
5035 | leaf = path->nodes[0]; | |
5036 | item = btrfs_item_ptr(leaf, path->slots[0], | |
5037 | struct btrfs_file_extent_item); | |
5038 | /* are we inside the extent that was found? */ | |
5039 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); | |
5040 | found_type = btrfs_key_type(&found_key); | |
5041 | if (found_key.objectid != objectid || | |
5042 | found_type != BTRFS_EXTENT_DATA_KEY) { | |
5043 | goto not_found; | |
5044 | } | |
5045 | ||
5046 | found_type = btrfs_file_extent_type(leaf, item); | |
5047 | extent_start = found_key.offset; | |
5048 | compressed = btrfs_file_extent_compression(leaf, item); | |
5049 | if (found_type == BTRFS_FILE_EXTENT_REG || | |
5050 | found_type == BTRFS_FILE_EXTENT_PREALLOC) { | |
5051 | extent_end = extent_start + | |
5052 | btrfs_file_extent_num_bytes(leaf, item); | |
5053 | } else if (found_type == BTRFS_FILE_EXTENT_INLINE) { | |
5054 | size_t size; | |
5055 | size = btrfs_file_extent_inline_len(leaf, item); | |
5056 | extent_end = (extent_start + size + root->sectorsize - 1) & | |
5057 | ~((u64)root->sectorsize - 1); | |
5058 | } | |
5059 | ||
5060 | if (start >= extent_end) { | |
5061 | path->slots[0]++; | |
5062 | if (path->slots[0] >= btrfs_header_nritems(leaf)) { | |
5063 | ret = btrfs_next_leaf(root, path); | |
5064 | if (ret < 0) { | |
5065 | err = ret; | |
5066 | goto out; | |
5067 | } | |
5068 | if (ret > 0) | |
5069 | goto not_found; | |
5070 | leaf = path->nodes[0]; | |
5071 | } | |
5072 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); | |
5073 | if (found_key.objectid != objectid || | |
5074 | found_key.type != BTRFS_EXTENT_DATA_KEY) | |
5075 | goto not_found; | |
5076 | if (start + len <= found_key.offset) | |
5077 | goto not_found; | |
5078 | em->start = start; | |
5079 | em->len = found_key.offset - start; | |
5080 | goto not_found_em; | |
5081 | } | |
5082 | ||
5083 | if (found_type == BTRFS_FILE_EXTENT_REG || | |
5084 | found_type == BTRFS_FILE_EXTENT_PREALLOC) { | |
5085 | em->start = extent_start; | |
5086 | em->len = extent_end - extent_start; | |
5087 | em->orig_start = extent_start - | |
5088 | btrfs_file_extent_offset(leaf, item); | |
5089 | bytenr = btrfs_file_extent_disk_bytenr(leaf, item); | |
5090 | if (bytenr == 0) { | |
5091 | em->block_start = EXTENT_MAP_HOLE; | |
5092 | goto insert; | |
5093 | } | |
5094 | if (compressed) { | |
5095 | set_bit(EXTENT_FLAG_COMPRESSED, &em->flags); | |
5096 | em->block_start = bytenr; | |
5097 | em->block_len = btrfs_file_extent_disk_num_bytes(leaf, | |
5098 | item); | |
5099 | } else { | |
5100 | bytenr += btrfs_file_extent_offset(leaf, item); | |
5101 | em->block_start = bytenr; | |
5102 | em->block_len = em->len; | |
5103 | if (found_type == BTRFS_FILE_EXTENT_PREALLOC) | |
5104 | set_bit(EXTENT_FLAG_PREALLOC, &em->flags); | |
5105 | } | |
5106 | goto insert; | |
5107 | } else if (found_type == BTRFS_FILE_EXTENT_INLINE) { | |
5108 | unsigned long ptr; | |
5109 | char *map; | |
5110 | size_t size; | |
5111 | size_t extent_offset; | |
5112 | size_t copy_size; | |
5113 | ||
5114 | em->block_start = EXTENT_MAP_INLINE; | |
5115 | if (!page || create) { | |
5116 | em->start = extent_start; | |
5117 | em->len = extent_end - extent_start; | |
5118 | goto out; | |
5119 | } | |
5120 | ||
5121 | size = btrfs_file_extent_inline_len(leaf, item); | |
5122 | extent_offset = page_offset(page) + pg_offset - extent_start; | |
5123 | copy_size = min_t(u64, PAGE_CACHE_SIZE - pg_offset, | |
5124 | size - extent_offset); | |
5125 | em->start = extent_start + extent_offset; | |
5126 | em->len = (copy_size + root->sectorsize - 1) & | |
5127 | ~((u64)root->sectorsize - 1); | |
5128 | em->orig_start = EXTENT_MAP_INLINE; | |
5129 | if (compressed) | |
5130 | set_bit(EXTENT_FLAG_COMPRESSED, &em->flags); | |
5131 | ptr = btrfs_file_extent_inline_start(item) + extent_offset; | |
5132 | if (create == 0 && !PageUptodate(page)) { | |
5133 | if (btrfs_file_extent_compression(leaf, item) == | |
5134 | BTRFS_COMPRESS_ZLIB) { | |
5135 | ret = uncompress_inline(path, inode, page, | |
5136 | pg_offset, | |
5137 | extent_offset, item); | |
5138 | BUG_ON(ret); | |
5139 | } else { | |
5140 | map = kmap(page); | |
5141 | read_extent_buffer(leaf, map + pg_offset, ptr, | |
5142 | copy_size); | |
5143 | if (pg_offset + copy_size < PAGE_CACHE_SIZE) { | |
5144 | memset(map + pg_offset + copy_size, 0, | |
5145 | PAGE_CACHE_SIZE - pg_offset - | |
5146 | copy_size); | |
5147 | } | |
5148 | kunmap(page); | |
5149 | } | |
5150 | flush_dcache_page(page); | |
5151 | } else if (create && PageUptodate(page)) { | |
5152 | WARN_ON(1); | |
5153 | if (!trans) { | |
5154 | kunmap(page); | |
5155 | free_extent_map(em); | |
5156 | em = NULL; | |
5157 | btrfs_release_path(root, path); | |
5158 | trans = btrfs_join_transaction(root, 1); | |
5159 | goto again; | |
5160 | } | |
5161 | map = kmap(page); | |
5162 | write_extent_buffer(leaf, map + pg_offset, ptr, | |
5163 | copy_size); | |
5164 | kunmap(page); | |
5165 | btrfs_mark_buffer_dirty(leaf); | |
5166 | } | |
5167 | set_extent_uptodate(io_tree, em->start, | |
5168 | extent_map_end(em) - 1, GFP_NOFS); | |
5169 | goto insert; | |
5170 | } else { | |
5171 | printk(KERN_ERR "btrfs unknown found_type %d\n", found_type); | |
5172 | WARN_ON(1); | |
5173 | } | |
5174 | not_found: | |
5175 | em->start = start; | |
5176 | em->len = len; | |
5177 | not_found_em: | |
5178 | em->block_start = EXTENT_MAP_HOLE; | |
5179 | set_bit(EXTENT_FLAG_VACANCY, &em->flags); | |
5180 | insert: | |
5181 | btrfs_release_path(root, path); | |
5182 | if (em->start > start || extent_map_end(em) <= start) { | |
5183 | printk(KERN_ERR "Btrfs: bad extent! em: [%llu %llu] passed " | |
5184 | "[%llu %llu]\n", (unsigned long long)em->start, | |
5185 | (unsigned long long)em->len, | |
5186 | (unsigned long long)start, | |
5187 | (unsigned long long)len); | |
5188 | err = -EIO; | |
5189 | goto out; | |
5190 | } | |
5191 | ||
5192 | err = 0; | |
5193 | write_lock(&em_tree->lock); | |
5194 | ret = add_extent_mapping(em_tree, em); | |
5195 | /* it is possible that someone inserted the extent into the tree | |
5196 | * while we had the lock dropped. It is also possible that | |
5197 | * an overlapping map exists in the tree | |
5198 | */ | |
5199 | if (ret == -EEXIST) { | |
5200 | struct extent_map *existing; | |
5201 | ||
5202 | ret = 0; | |
5203 | ||
5204 | existing = lookup_extent_mapping(em_tree, start, len); | |
5205 | if (existing && (existing->start > start || | |
5206 | existing->start + existing->len <= start)) { | |
5207 | free_extent_map(existing); | |
5208 | existing = NULL; | |
5209 | } | |
5210 | if (!existing) { | |
5211 | existing = lookup_extent_mapping(em_tree, em->start, | |
5212 | em->len); | |
5213 | if (existing) { | |
5214 | err = merge_extent_mapping(em_tree, existing, | |
5215 | em, start, | |
5216 | root->sectorsize); | |
5217 | free_extent_map(existing); | |
5218 | if (err) { | |
5219 | free_extent_map(em); | |
5220 | em = NULL; | |
5221 | } | |
5222 | } else { | |
5223 | err = -EIO; | |
5224 | free_extent_map(em); | |
5225 | em = NULL; | |
5226 | } | |
5227 | } else { | |
5228 | free_extent_map(em); | |
5229 | em = existing; | |
5230 | err = 0; | |
5231 | } | |
5232 | } | |
5233 | write_unlock(&em_tree->lock); | |
5234 | out: | |
5235 | if (path) | |
5236 | btrfs_free_path(path); | |
5237 | if (trans) { | |
5238 | ret = btrfs_end_transaction(trans, root); | |
5239 | if (!err) | |
5240 | err = ret; | |
5241 | } | |
5242 | if (err) { | |
5243 | free_extent_map(em); | |
5244 | return ERR_PTR(err); | |
5245 | } | |
5246 | return em; | |
5247 | } | |
5248 | ||
5249 | static struct extent_map *btrfs_new_extent_direct(struct inode *inode, | |
5250 | u64 start, u64 len) | |
5251 | { | |
5252 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
5253 | struct btrfs_trans_handle *trans; | |
5254 | struct extent_map *em; | |
5255 | struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; | |
5256 | struct btrfs_key ins; | |
5257 | u64 alloc_hint; | |
5258 | int ret; | |
5259 | ||
5260 | btrfs_drop_extent_cache(inode, start, start + len - 1, 0); | |
5261 | ||
5262 | trans = btrfs_join_transaction(root, 0); | |
5263 | if (!trans) | |
5264 | return ERR_PTR(-ENOMEM); | |
5265 | ||
5266 | trans->block_rsv = &root->fs_info->delalloc_block_rsv; | |
5267 | ||
5268 | alloc_hint = get_extent_allocation_hint(inode, start, len); | |
5269 | ret = btrfs_reserve_extent(trans, root, len, root->sectorsize, 0, | |
5270 | alloc_hint, (u64)-1, &ins, 1); | |
5271 | if (ret) { | |
5272 | em = ERR_PTR(ret); | |
5273 | goto out; | |
5274 | } | |
5275 | ||
5276 | em = alloc_extent_map(GFP_NOFS); | |
5277 | if (!em) { | |
5278 | em = ERR_PTR(-ENOMEM); | |
5279 | goto out; | |
5280 | } | |
5281 | ||
5282 | em->start = start; | |
5283 | em->orig_start = em->start; | |
5284 | em->len = ins.offset; | |
5285 | ||
5286 | em->block_start = ins.objectid; | |
5287 | em->block_len = ins.offset; | |
5288 | em->bdev = root->fs_info->fs_devices->latest_bdev; | |
5289 | set_bit(EXTENT_FLAG_PINNED, &em->flags); | |
5290 | ||
5291 | while (1) { | |
5292 | write_lock(&em_tree->lock); | |
5293 | ret = add_extent_mapping(em_tree, em); | |
5294 | write_unlock(&em_tree->lock); | |
5295 | if (ret != -EEXIST) | |
5296 | break; | |
5297 | btrfs_drop_extent_cache(inode, start, start + em->len - 1, 0); | |
5298 | } | |
5299 | ||
5300 | ret = btrfs_add_ordered_extent_dio(inode, start, ins.objectid, | |
5301 | ins.offset, ins.offset, 0); | |
5302 | if (ret) { | |
5303 | btrfs_free_reserved_extent(root, ins.objectid, ins.offset); | |
5304 | em = ERR_PTR(ret); | |
5305 | } | |
5306 | out: | |
5307 | btrfs_end_transaction(trans, root); | |
5308 | return em; | |
5309 | } | |
5310 | ||
5311 | /* | |
5312 | * returns 1 when the nocow is safe, < 1 on error, 0 if the | |
5313 | * block must be cow'd | |
5314 | */ | |
5315 | static noinline int can_nocow_odirect(struct btrfs_trans_handle *trans, | |
5316 | struct inode *inode, u64 offset, u64 len) | |
5317 | { | |
5318 | struct btrfs_path *path; | |
5319 | int ret; | |
5320 | struct extent_buffer *leaf; | |
5321 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
5322 | struct btrfs_file_extent_item *fi; | |
5323 | struct btrfs_key key; | |
5324 | u64 disk_bytenr; | |
5325 | u64 backref_offset; | |
5326 | u64 extent_end; | |
5327 | u64 num_bytes; | |
5328 | int slot; | |
5329 | int found_type; | |
5330 | ||
5331 | path = btrfs_alloc_path(); | |
5332 | if (!path) | |
5333 | return -ENOMEM; | |
5334 | ||
5335 | ret = btrfs_lookup_file_extent(trans, root, path, inode->i_ino, | |
5336 | offset, 0); | |
5337 | if (ret < 0) | |
5338 | goto out; | |
5339 | ||
5340 | slot = path->slots[0]; | |
5341 | if (ret == 1) { | |
5342 | if (slot == 0) { | |
5343 | /* can't find the item, must cow */ | |
5344 | ret = 0; | |
5345 | goto out; | |
5346 | } | |
5347 | slot--; | |
5348 | } | |
5349 | ret = 0; | |
5350 | leaf = path->nodes[0]; | |
5351 | btrfs_item_key_to_cpu(leaf, &key, slot); | |
5352 | if (key.objectid != inode->i_ino || | |
5353 | key.type != BTRFS_EXTENT_DATA_KEY) { | |
5354 | /* not our file or wrong item type, must cow */ | |
5355 | goto out; | |
5356 | } | |
5357 | ||
5358 | if (key.offset > offset) { | |
5359 | /* Wrong offset, must cow */ | |
5360 | goto out; | |
5361 | } | |
5362 | ||
5363 | fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item); | |
5364 | found_type = btrfs_file_extent_type(leaf, fi); | |
5365 | if (found_type != BTRFS_FILE_EXTENT_REG && | |
5366 | found_type != BTRFS_FILE_EXTENT_PREALLOC) { | |
5367 | /* not a regular extent, must cow */ | |
5368 | goto out; | |
5369 | } | |
5370 | disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); | |
5371 | backref_offset = btrfs_file_extent_offset(leaf, fi); | |
5372 | ||
5373 | extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi); | |
5374 | if (extent_end < offset + len) { | |
5375 | /* extent doesn't include our full range, must cow */ | |
5376 | goto out; | |
5377 | } | |
5378 | ||
5379 | if (btrfs_extent_readonly(root, disk_bytenr)) | |
5380 | goto out; | |
5381 | ||
5382 | /* | |
5383 | * look for other files referencing this extent, if we | |
5384 | * find any we must cow | |
5385 | */ | |
5386 | if (btrfs_cross_ref_exist(trans, root, inode->i_ino, | |
5387 | key.offset - backref_offset, disk_bytenr)) | |
5388 | goto out; | |
5389 | ||
5390 | /* | |
5391 | * adjust disk_bytenr and num_bytes to cover just the bytes | |
5392 | * in this extent we are about to write. If there | |
5393 | * are any csums in that range we have to cow in order | |
5394 | * to keep the csums correct | |
5395 | */ | |
5396 | disk_bytenr += backref_offset; | |
5397 | disk_bytenr += offset - key.offset; | |
5398 | num_bytes = min(offset + len, extent_end) - offset; | |
5399 | if (csum_exist_in_range(root, disk_bytenr, num_bytes)) | |
5400 | goto out; | |
5401 | /* | |
5402 | * all of the above have passed, it is safe to overwrite this extent | |
5403 | * without cow | |
5404 | */ | |
5405 | ret = 1; | |
5406 | out: | |
5407 | btrfs_free_path(path); | |
5408 | return ret; | |
5409 | } | |
5410 | ||
5411 | static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock, | |
5412 | struct buffer_head *bh_result, int create) | |
5413 | { | |
5414 | struct extent_map *em; | |
5415 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
5416 | u64 start = iblock << inode->i_blkbits; | |
5417 | u64 len = bh_result->b_size; | |
5418 | struct btrfs_trans_handle *trans; | |
5419 | ||
5420 | em = btrfs_get_extent(inode, NULL, 0, start, len, 0); | |
5421 | if (IS_ERR(em)) | |
5422 | return PTR_ERR(em); | |
5423 | ||
5424 | /* | |
5425 | * Ok for INLINE and COMPRESSED extents we need to fallback on buffered | |
5426 | * io. INLINE is special, and we could probably kludge it in here, but | |
5427 | * it's still buffered so for safety lets just fall back to the generic | |
5428 | * buffered path. | |
5429 | * | |
5430 | * For COMPRESSED we _have_ to read the entire extent in so we can | |
5431 | * decompress it, so there will be buffering required no matter what we | |
5432 | * do, so go ahead and fallback to buffered. | |
5433 | * | |
5434 | * We return -ENOTBLK because thats what makes DIO go ahead and go back | |
5435 | * to buffered IO. Don't blame me, this is the price we pay for using | |
5436 | * the generic code. | |
5437 | */ | |
5438 | if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags) || | |
5439 | em->block_start == EXTENT_MAP_INLINE) { | |
5440 | free_extent_map(em); | |
5441 | return -ENOTBLK; | |
5442 | } | |
5443 | ||
5444 | /* Just a good old fashioned hole, return */ | |
5445 | if (!create && (em->block_start == EXTENT_MAP_HOLE || | |
5446 | test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) { | |
5447 | free_extent_map(em); | |
5448 | /* DIO will do one hole at a time, so just unlock a sector */ | |
5449 | unlock_extent(&BTRFS_I(inode)->io_tree, start, | |
5450 | start + root->sectorsize - 1, GFP_NOFS); | |
5451 | return 0; | |
5452 | } | |
5453 | ||
5454 | /* | |
5455 | * We don't allocate a new extent in the following cases | |
5456 | * | |
5457 | * 1) The inode is marked as NODATACOW. In this case we'll just use the | |
5458 | * existing extent. | |
5459 | * 2) The extent is marked as PREALLOC. We're good to go here and can | |
5460 | * just use the extent. | |
5461 | * | |
5462 | */ | |
5463 | if (!create) { | |
5464 | len = em->len - (start - em->start); | |
5465 | goto map; | |
5466 | } | |
5467 | ||
5468 | if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags) || | |
5469 | ((BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) && | |
5470 | em->block_start != EXTENT_MAP_HOLE)) { | |
5471 | int type; | |
5472 | int ret; | |
5473 | u64 block_start; | |
5474 | ||
5475 | if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) | |
5476 | type = BTRFS_ORDERED_PREALLOC; | |
5477 | else | |
5478 | type = BTRFS_ORDERED_NOCOW; | |
5479 | len = min(len, em->len - (start - em->start)); | |
5480 | block_start = em->block_start + (start - em->start); | |
5481 | ||
5482 | /* | |
5483 | * we're not going to log anything, but we do need | |
5484 | * to make sure the current transaction stays open | |
5485 | * while we look for nocow cross refs | |
5486 | */ | |
5487 | trans = btrfs_join_transaction(root, 0); | |
5488 | if (!trans) | |
5489 | goto must_cow; | |
5490 | ||
5491 | if (can_nocow_odirect(trans, inode, start, len) == 1) { | |
5492 | ret = btrfs_add_ordered_extent_dio(inode, start, | |
5493 | block_start, len, len, type); | |
5494 | btrfs_end_transaction(trans, root); | |
5495 | if (ret) { | |
5496 | free_extent_map(em); | |
5497 | return ret; | |
5498 | } | |
5499 | goto unlock; | |
5500 | } | |
5501 | btrfs_end_transaction(trans, root); | |
5502 | } | |
5503 | must_cow: | |
5504 | /* | |
5505 | * this will cow the extent, reset the len in case we changed | |
5506 | * it above | |
5507 | */ | |
5508 | len = bh_result->b_size; | |
5509 | free_extent_map(em); | |
5510 | em = btrfs_new_extent_direct(inode, start, len); | |
5511 | if (IS_ERR(em)) | |
5512 | return PTR_ERR(em); | |
5513 | len = min(len, em->len - (start - em->start)); | |
5514 | unlock: | |
5515 | clear_extent_bit(&BTRFS_I(inode)->io_tree, start, start + len - 1, | |
5516 | EXTENT_LOCKED | EXTENT_DELALLOC | EXTENT_DIRTY, 1, | |
5517 | 0, NULL, GFP_NOFS); | |
5518 | map: | |
5519 | bh_result->b_blocknr = (em->block_start + (start - em->start)) >> | |
5520 | inode->i_blkbits; | |
5521 | bh_result->b_size = len; | |
5522 | bh_result->b_bdev = em->bdev; | |
5523 | set_buffer_mapped(bh_result); | |
5524 | if (create && !test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) | |
5525 | set_buffer_new(bh_result); | |
5526 | ||
5527 | free_extent_map(em); | |
5528 | ||
5529 | return 0; | |
5530 | } | |
5531 | ||
5532 | struct btrfs_dio_private { | |
5533 | struct inode *inode; | |
5534 | u64 logical_offset; | |
5535 | u64 disk_bytenr; | |
5536 | u64 bytes; | |
5537 | u32 *csums; | |
5538 | void *private; | |
5539 | ||
5540 | /* number of bios pending for this dio */ | |
5541 | atomic_t pending_bios; | |
5542 | ||
5543 | /* IO errors */ | |
5544 | int errors; | |
5545 | ||
5546 | struct bio *orig_bio; | |
5547 | }; | |
5548 | ||
5549 | static void btrfs_endio_direct_read(struct bio *bio, int err) | |
5550 | { | |
5551 | struct btrfs_dio_private *dip = bio->bi_private; | |
5552 | struct bio_vec *bvec_end = bio->bi_io_vec + bio->bi_vcnt - 1; | |
5553 | struct bio_vec *bvec = bio->bi_io_vec; | |
5554 | struct inode *inode = dip->inode; | |
5555 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
5556 | u64 start; | |
5557 | u32 *private = dip->csums; | |
5558 | ||
5559 | start = dip->logical_offset; | |
5560 | do { | |
5561 | if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) { | |
5562 | struct page *page = bvec->bv_page; | |
5563 | char *kaddr; | |
5564 | u32 csum = ~(u32)0; | |
5565 | unsigned long flags; | |
5566 | ||
5567 | local_irq_save(flags); | |
5568 | kaddr = kmap_atomic(page, KM_IRQ0); | |
5569 | csum = btrfs_csum_data(root, kaddr + bvec->bv_offset, | |
5570 | csum, bvec->bv_len); | |
5571 | btrfs_csum_final(csum, (char *)&csum); | |
5572 | kunmap_atomic(kaddr, KM_IRQ0); | |
5573 | local_irq_restore(flags); | |
5574 | ||
5575 | flush_dcache_page(bvec->bv_page); | |
5576 | if (csum != *private) { | |
5577 | printk(KERN_ERR "btrfs csum failed ino %lu off" | |
5578 | " %llu csum %u private %u\n", | |
5579 | inode->i_ino, (unsigned long long)start, | |
5580 | csum, *private); | |
5581 | err = -EIO; | |
5582 | } | |
5583 | } | |
5584 | ||
5585 | start += bvec->bv_len; | |
5586 | private++; | |
5587 | bvec++; | |
5588 | } while (bvec <= bvec_end); | |
5589 | ||
5590 | unlock_extent(&BTRFS_I(inode)->io_tree, dip->logical_offset, | |
5591 | dip->logical_offset + dip->bytes - 1, GFP_NOFS); | |
5592 | bio->bi_private = dip->private; | |
5593 | ||
5594 | kfree(dip->csums); | |
5595 | kfree(dip); | |
5596 | dio_end_io(bio, err); | |
5597 | } | |
5598 | ||
5599 | static void btrfs_endio_direct_write(struct bio *bio, int err) | |
5600 | { | |
5601 | struct btrfs_dio_private *dip = bio->bi_private; | |
5602 | struct inode *inode = dip->inode; | |
5603 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
5604 | struct btrfs_trans_handle *trans; | |
5605 | struct btrfs_ordered_extent *ordered = NULL; | |
5606 | struct extent_state *cached_state = NULL; | |
5607 | int ret; | |
5608 | ||
5609 | if (err) | |
5610 | goto out_done; | |
5611 | ||
5612 | ret = btrfs_dec_test_ordered_pending(inode, &ordered, | |
5613 | dip->logical_offset, dip->bytes); | |
5614 | if (!ret) | |
5615 | goto out_done; | |
5616 | ||
5617 | BUG_ON(!ordered); | |
5618 | ||
5619 | trans = btrfs_join_transaction(root, 1); | |
5620 | if (!trans) { | |
5621 | err = -ENOMEM; | |
5622 | goto out; | |
5623 | } | |
5624 | trans->block_rsv = &root->fs_info->delalloc_block_rsv; | |
5625 | ||
5626 | if (test_bit(BTRFS_ORDERED_NOCOW, &ordered->flags)) { | |
5627 | ret = btrfs_ordered_update_i_size(inode, 0, ordered); | |
5628 | if (!ret) | |
5629 | ret = btrfs_update_inode(trans, root, inode); | |
5630 | err = ret; | |
5631 | goto out; | |
5632 | } | |
5633 | ||
5634 | lock_extent_bits(&BTRFS_I(inode)->io_tree, ordered->file_offset, | |
5635 | ordered->file_offset + ordered->len - 1, 0, | |
5636 | &cached_state, GFP_NOFS); | |
5637 | ||
5638 | if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered->flags)) { | |
5639 | ret = btrfs_mark_extent_written(trans, inode, | |
5640 | ordered->file_offset, | |
5641 | ordered->file_offset + | |
5642 | ordered->len); | |
5643 | if (ret) { | |
5644 | err = ret; | |
5645 | goto out_unlock; | |
5646 | } | |
5647 | } else { | |
5648 | ret = insert_reserved_file_extent(trans, inode, | |
5649 | ordered->file_offset, | |
5650 | ordered->start, | |
5651 | ordered->disk_len, | |
5652 | ordered->len, | |
5653 | ordered->len, | |
5654 | 0, 0, 0, | |
5655 | BTRFS_FILE_EXTENT_REG); | |
5656 | unpin_extent_cache(&BTRFS_I(inode)->extent_tree, | |
5657 | ordered->file_offset, ordered->len); | |
5658 | if (ret) { | |
5659 | err = ret; | |
5660 | WARN_ON(1); | |
5661 | goto out_unlock; | |
5662 | } | |
5663 | } | |
5664 | ||
5665 | add_pending_csums(trans, inode, ordered->file_offset, &ordered->list); | |
5666 | btrfs_ordered_update_i_size(inode, 0, ordered); | |
5667 | btrfs_update_inode(trans, root, inode); | |
5668 | out_unlock: | |
5669 | unlock_extent_cached(&BTRFS_I(inode)->io_tree, ordered->file_offset, | |
5670 | ordered->file_offset + ordered->len - 1, | |
5671 | &cached_state, GFP_NOFS); | |
5672 | out: | |
5673 | btrfs_delalloc_release_metadata(inode, ordered->len); | |
5674 | btrfs_end_transaction(trans, root); | |
5675 | btrfs_put_ordered_extent(ordered); | |
5676 | btrfs_put_ordered_extent(ordered); | |
5677 | out_done: | |
5678 | bio->bi_private = dip->private; | |
5679 | ||
5680 | kfree(dip->csums); | |
5681 | kfree(dip); | |
5682 | dio_end_io(bio, err); | |
5683 | } | |
5684 | ||
5685 | static int __btrfs_submit_bio_start_direct_io(struct inode *inode, int rw, | |
5686 | struct bio *bio, int mirror_num, | |
5687 | unsigned long bio_flags, u64 offset) | |
5688 | { | |
5689 | int ret; | |
5690 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
5691 | ret = btrfs_csum_one_bio(root, inode, bio, offset, 1); | |
5692 | BUG_ON(ret); | |
5693 | return 0; | |
5694 | } | |
5695 | ||
5696 | static void btrfs_end_dio_bio(struct bio *bio, int err) | |
5697 | { | |
5698 | struct btrfs_dio_private *dip = bio->bi_private; | |
5699 | ||
5700 | if (err) { | |
5701 | printk(KERN_ERR "btrfs direct IO failed ino %lu rw %lu " | |
5702 | "disk_bytenr %lu len %u err no %d\n", | |
5703 | dip->inode->i_ino, bio->bi_rw, bio->bi_sector, | |
5704 | bio->bi_size, err); | |
5705 | dip->errors = 1; | |
5706 | ||
5707 | /* | |
5708 | * before atomic variable goto zero, we must make sure | |
5709 | * dip->errors is perceived to be set. | |
5710 | */ | |
5711 | smp_mb__before_atomic_dec(); | |
5712 | } | |
5713 | ||
5714 | /* if there are more bios still pending for this dio, just exit */ | |
5715 | if (!atomic_dec_and_test(&dip->pending_bios)) | |
5716 | goto out; | |
5717 | ||
5718 | if (dip->errors) | |
5719 | bio_io_error(dip->orig_bio); | |
5720 | else { | |
5721 | set_bit(BIO_UPTODATE, &dip->orig_bio->bi_flags); | |
5722 | bio_endio(dip->orig_bio, 0); | |
5723 | } | |
5724 | out: | |
5725 | bio_put(bio); | |
5726 | } | |
5727 | ||
5728 | static struct bio *btrfs_dio_bio_alloc(struct block_device *bdev, | |
5729 | u64 first_sector, gfp_t gfp_flags) | |
5730 | { | |
5731 | int nr_vecs = bio_get_nr_vecs(bdev); | |
5732 | return btrfs_bio_alloc(bdev, first_sector, nr_vecs, gfp_flags); | |
5733 | } | |
5734 | ||
5735 | static inline int __btrfs_submit_dio_bio(struct bio *bio, struct inode *inode, | |
5736 | int rw, u64 file_offset, int skip_sum, | |
5737 | u32 *csums) | |
5738 | { | |
5739 | int write = rw & REQ_WRITE; | |
5740 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
5741 | int ret; | |
5742 | ||
5743 | bio_get(bio); | |
5744 | ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0); | |
5745 | if (ret) | |
5746 | goto err; | |
5747 | ||
5748 | if (write && !skip_sum) { | |
5749 | ret = btrfs_wq_submit_bio(root->fs_info, | |
5750 | inode, rw, bio, 0, 0, | |
5751 | file_offset, | |
5752 | __btrfs_submit_bio_start_direct_io, | |
5753 | __btrfs_submit_bio_done); | |
5754 | goto err; | |
5755 | } else if (!skip_sum) | |
5756 | btrfs_lookup_bio_sums_dio(root, inode, bio, | |
5757 | file_offset, csums); | |
5758 | ||
5759 | ret = btrfs_map_bio(root, rw, bio, 0, 1); | |
5760 | err: | |
5761 | bio_put(bio); | |
5762 | return ret; | |
5763 | } | |
5764 | ||
5765 | static int btrfs_submit_direct_hook(int rw, struct btrfs_dio_private *dip, | |
5766 | int skip_sum) | |
5767 | { | |
5768 | struct inode *inode = dip->inode; | |
5769 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
5770 | struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree; | |
5771 | struct bio *bio; | |
5772 | struct bio *orig_bio = dip->orig_bio; | |
5773 | struct bio_vec *bvec = orig_bio->bi_io_vec; | |
5774 | u64 start_sector = orig_bio->bi_sector; | |
5775 | u64 file_offset = dip->logical_offset; | |
5776 | u64 submit_len = 0; | |
5777 | u64 map_length; | |
5778 | int nr_pages = 0; | |
5779 | u32 *csums = dip->csums; | |
5780 | int ret = 0; | |
5781 | ||
5782 | bio = btrfs_dio_bio_alloc(orig_bio->bi_bdev, start_sector, GFP_NOFS); | |
5783 | if (!bio) | |
5784 | return -ENOMEM; | |
5785 | bio->bi_private = dip; | |
5786 | bio->bi_end_io = btrfs_end_dio_bio; | |
5787 | atomic_inc(&dip->pending_bios); | |
5788 | ||
5789 | map_length = orig_bio->bi_size; | |
5790 | ret = btrfs_map_block(map_tree, READ, start_sector << 9, | |
5791 | &map_length, NULL, 0); | |
5792 | if (ret) { | |
5793 | bio_put(bio); | |
5794 | return -EIO; | |
5795 | } | |
5796 | ||
5797 | while (bvec <= (orig_bio->bi_io_vec + orig_bio->bi_vcnt - 1)) { | |
5798 | if (unlikely(map_length < submit_len + bvec->bv_len || | |
5799 | bio_add_page(bio, bvec->bv_page, bvec->bv_len, | |
5800 | bvec->bv_offset) < bvec->bv_len)) { | |
5801 | /* | |
5802 | * inc the count before we submit the bio so | |
5803 | * we know the end IO handler won't happen before | |
5804 | * we inc the count. Otherwise, the dip might get freed | |
5805 | * before we're done setting it up | |
5806 | */ | |
5807 | atomic_inc(&dip->pending_bios); | |
5808 | ret = __btrfs_submit_dio_bio(bio, inode, rw, | |
5809 | file_offset, skip_sum, | |
5810 | csums); | |
5811 | if (ret) { | |
5812 | bio_put(bio); | |
5813 | atomic_dec(&dip->pending_bios); | |
5814 | goto out_err; | |
5815 | } | |
5816 | ||
5817 | if (!skip_sum) | |
5818 | csums = csums + nr_pages; | |
5819 | start_sector += submit_len >> 9; | |
5820 | file_offset += submit_len; | |
5821 | ||
5822 | submit_len = 0; | |
5823 | nr_pages = 0; | |
5824 | ||
5825 | bio = btrfs_dio_bio_alloc(orig_bio->bi_bdev, | |
5826 | start_sector, GFP_NOFS); | |
5827 | if (!bio) | |
5828 | goto out_err; | |
5829 | bio->bi_private = dip; | |
5830 | bio->bi_end_io = btrfs_end_dio_bio; | |
5831 | ||
5832 | map_length = orig_bio->bi_size; | |
5833 | ret = btrfs_map_block(map_tree, READ, start_sector << 9, | |
5834 | &map_length, NULL, 0); | |
5835 | if (ret) { | |
5836 | bio_put(bio); | |
5837 | goto out_err; | |
5838 | } | |
5839 | } else { | |
5840 | submit_len += bvec->bv_len; | |
5841 | nr_pages ++; | |
5842 | bvec++; | |
5843 | } | |
5844 | } | |
5845 | ||
5846 | ret = __btrfs_submit_dio_bio(bio, inode, rw, file_offset, skip_sum, | |
5847 | csums); | |
5848 | if (!ret) | |
5849 | return 0; | |
5850 | ||
5851 | bio_put(bio); | |
5852 | out_err: | |
5853 | dip->errors = 1; | |
5854 | /* | |
5855 | * before atomic variable goto zero, we must | |
5856 | * make sure dip->errors is perceived to be set. | |
5857 | */ | |
5858 | smp_mb__before_atomic_dec(); | |
5859 | if (atomic_dec_and_test(&dip->pending_bios)) | |
5860 | bio_io_error(dip->orig_bio); | |
5861 | ||
5862 | /* bio_end_io() will handle error, so we needn't return it */ | |
5863 | return 0; | |
5864 | } | |
5865 | ||
5866 | static void btrfs_submit_direct(int rw, struct bio *bio, struct inode *inode, | |
5867 | loff_t file_offset) | |
5868 | { | |
5869 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
5870 | struct btrfs_dio_private *dip; | |
5871 | struct bio_vec *bvec = bio->bi_io_vec; | |
5872 | int skip_sum; | |
5873 | int write = rw & REQ_WRITE; | |
5874 | int ret = 0; | |
5875 | ||
5876 | skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM; | |
5877 | ||
5878 | dip = kmalloc(sizeof(*dip), GFP_NOFS); | |
5879 | if (!dip) { | |
5880 | ret = -ENOMEM; | |
5881 | goto free_ordered; | |
5882 | } | |
5883 | dip->csums = NULL; | |
5884 | ||
5885 | if (!skip_sum) { | |
5886 | dip->csums = kmalloc(sizeof(u32) * bio->bi_vcnt, GFP_NOFS); | |
5887 | if (!dip->csums) { | |
5888 | ret = -ENOMEM; | |
5889 | goto free_ordered; | |
5890 | } | |
5891 | } | |
5892 | ||
5893 | dip->private = bio->bi_private; | |
5894 | dip->inode = inode; | |
5895 | dip->logical_offset = file_offset; | |
5896 | ||
5897 | dip->bytes = 0; | |
5898 | do { | |
5899 | dip->bytes += bvec->bv_len; | |
5900 | bvec++; | |
5901 | } while (bvec <= (bio->bi_io_vec + bio->bi_vcnt - 1)); | |
5902 | ||
5903 | dip->disk_bytenr = (u64)bio->bi_sector << 9; | |
5904 | bio->bi_private = dip; | |
5905 | dip->errors = 0; | |
5906 | dip->orig_bio = bio; | |
5907 | atomic_set(&dip->pending_bios, 0); | |
5908 | ||
5909 | if (write) | |
5910 | bio->bi_end_io = btrfs_endio_direct_write; | |
5911 | else | |
5912 | bio->bi_end_io = btrfs_endio_direct_read; | |
5913 | ||
5914 | ret = btrfs_submit_direct_hook(rw, dip, skip_sum); | |
5915 | if (!ret) | |
5916 | return; | |
5917 | free_ordered: | |
5918 | /* | |
5919 | * If this is a write, we need to clean up the reserved space and kill | |
5920 | * the ordered extent. | |
5921 | */ | |
5922 | if (write) { | |
5923 | struct btrfs_ordered_extent *ordered; | |
5924 | ordered = btrfs_lookup_ordered_extent(inode, | |
5925 | dip->logical_offset); | |
5926 | if (!test_bit(BTRFS_ORDERED_PREALLOC, &ordered->flags) && | |
5927 | !test_bit(BTRFS_ORDERED_NOCOW, &ordered->flags)) | |
5928 | btrfs_free_reserved_extent(root, ordered->start, | |
5929 | ordered->disk_len); | |
5930 | btrfs_put_ordered_extent(ordered); | |
5931 | btrfs_put_ordered_extent(ordered); | |
5932 | } | |
5933 | bio_endio(bio, ret); | |
5934 | } | |
5935 | ||
5936 | static ssize_t check_direct_IO(struct btrfs_root *root, int rw, struct kiocb *iocb, | |
5937 | const struct iovec *iov, loff_t offset, | |
5938 | unsigned long nr_segs) | |
5939 | { | |
5940 | int seg; | |
5941 | size_t size; | |
5942 | unsigned long addr; | |
5943 | unsigned blocksize_mask = root->sectorsize - 1; | |
5944 | ssize_t retval = -EINVAL; | |
5945 | loff_t end = offset; | |
5946 | ||
5947 | if (offset & blocksize_mask) | |
5948 | goto out; | |
5949 | ||
5950 | /* Check the memory alignment. Blocks cannot straddle pages */ | |
5951 | for (seg = 0; seg < nr_segs; seg++) { | |
5952 | addr = (unsigned long)iov[seg].iov_base; | |
5953 | size = iov[seg].iov_len; | |
5954 | end += size; | |
5955 | if ((addr & blocksize_mask) || (size & blocksize_mask)) | |
5956 | goto out; | |
5957 | } | |
5958 | retval = 0; | |
5959 | out: | |
5960 | return retval; | |
5961 | } | |
5962 | static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb, | |
5963 | const struct iovec *iov, loff_t offset, | |
5964 | unsigned long nr_segs) | |
5965 | { | |
5966 | struct file *file = iocb->ki_filp; | |
5967 | struct inode *inode = file->f_mapping->host; | |
5968 | struct btrfs_ordered_extent *ordered; | |
5969 | struct extent_state *cached_state = NULL; | |
5970 | u64 lockstart, lockend; | |
5971 | ssize_t ret; | |
5972 | int writing = rw & WRITE; | |
5973 | int write_bits = 0; | |
5974 | size_t count = iov_length(iov, nr_segs); | |
5975 | ||
5976 | if (check_direct_IO(BTRFS_I(inode)->root, rw, iocb, iov, | |
5977 | offset, nr_segs)) { | |
5978 | return 0; | |
5979 | } | |
5980 | ||
5981 | lockstart = offset; | |
5982 | lockend = offset + count - 1; | |
5983 | ||
5984 | if (writing) { | |
5985 | ret = btrfs_delalloc_reserve_space(inode, count); | |
5986 | if (ret) | |
5987 | goto out; | |
5988 | } | |
5989 | ||
5990 | while (1) { | |
5991 | lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend, | |
5992 | 0, &cached_state, GFP_NOFS); | |
5993 | /* | |
5994 | * We're concerned with the entire range that we're going to be | |
5995 | * doing DIO to, so we need to make sure theres no ordered | |
5996 | * extents in this range. | |
5997 | */ | |
5998 | ordered = btrfs_lookup_ordered_range(inode, lockstart, | |
5999 | lockend - lockstart + 1); | |
6000 | if (!ordered) | |
6001 | break; | |
6002 | unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend, | |
6003 | &cached_state, GFP_NOFS); | |
6004 | btrfs_start_ordered_extent(inode, ordered, 1); | |
6005 | btrfs_put_ordered_extent(ordered); | |
6006 | cond_resched(); | |
6007 | } | |
6008 | ||
6009 | /* | |
6010 | * we don't use btrfs_set_extent_delalloc because we don't want | |
6011 | * the dirty or uptodate bits | |
6012 | */ | |
6013 | if (writing) { | |
6014 | write_bits = EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING; | |
6015 | ret = set_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend, | |
6016 | EXTENT_DELALLOC, 0, NULL, &cached_state, | |
6017 | GFP_NOFS); | |
6018 | if (ret) { | |
6019 | clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, | |
6020 | lockend, EXTENT_LOCKED | write_bits, | |
6021 | 1, 0, &cached_state, GFP_NOFS); | |
6022 | goto out; | |
6023 | } | |
6024 | } | |
6025 | ||
6026 | free_extent_state(cached_state); | |
6027 | cached_state = NULL; | |
6028 | ||
6029 | ret = __blockdev_direct_IO(rw, iocb, inode, | |
6030 | BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev, | |
6031 | iov, offset, nr_segs, btrfs_get_blocks_direct, NULL, | |
6032 | btrfs_submit_direct, 0); | |
6033 | ||
6034 | if (ret < 0 && ret != -EIOCBQUEUED) { | |
6035 | clear_extent_bit(&BTRFS_I(inode)->io_tree, offset, | |
6036 | offset + iov_length(iov, nr_segs) - 1, | |
6037 | EXTENT_LOCKED | write_bits, 1, 0, | |
6038 | &cached_state, GFP_NOFS); | |
6039 | } else if (ret >= 0 && ret < iov_length(iov, nr_segs)) { | |
6040 | /* | |
6041 | * We're falling back to buffered, unlock the section we didn't | |
6042 | * do IO on. | |
6043 | */ | |
6044 | clear_extent_bit(&BTRFS_I(inode)->io_tree, offset + ret, | |
6045 | offset + iov_length(iov, nr_segs) - 1, | |
6046 | EXTENT_LOCKED | write_bits, 1, 0, | |
6047 | &cached_state, GFP_NOFS); | |
6048 | } | |
6049 | out: | |
6050 | free_extent_state(cached_state); | |
6051 | return ret; | |
6052 | } | |
6053 | ||
6054 | static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, | |
6055 | __u64 start, __u64 len) | |
6056 | { | |
6057 | return extent_fiemap(inode, fieinfo, start, len, btrfs_get_extent); | |
6058 | } | |
6059 | ||
6060 | int btrfs_readpage(struct file *file, struct page *page) | |
6061 | { | |
6062 | struct extent_io_tree *tree; | |
6063 | tree = &BTRFS_I(page->mapping->host)->io_tree; | |
6064 | return extent_read_full_page(tree, page, btrfs_get_extent); | |
6065 | } | |
6066 | ||
6067 | static int btrfs_writepage(struct page *page, struct writeback_control *wbc) | |
6068 | { | |
6069 | struct extent_io_tree *tree; | |
6070 | ||
6071 | ||
6072 | if (current->flags & PF_MEMALLOC) { | |
6073 | redirty_page_for_writepage(wbc, page); | |
6074 | unlock_page(page); | |
6075 | return 0; | |
6076 | } | |
6077 | tree = &BTRFS_I(page->mapping->host)->io_tree; | |
6078 | return extent_write_full_page(tree, page, btrfs_get_extent, wbc); | |
6079 | } | |
6080 | ||
6081 | int btrfs_writepages(struct address_space *mapping, | |
6082 | struct writeback_control *wbc) | |
6083 | { | |
6084 | struct extent_io_tree *tree; | |
6085 | ||
6086 | tree = &BTRFS_I(mapping->host)->io_tree; | |
6087 | return extent_writepages(tree, mapping, btrfs_get_extent, wbc); | |
6088 | } | |
6089 | ||
6090 | static int | |
6091 | btrfs_readpages(struct file *file, struct address_space *mapping, | |
6092 | struct list_head *pages, unsigned nr_pages) | |
6093 | { | |
6094 | struct extent_io_tree *tree; | |
6095 | tree = &BTRFS_I(mapping->host)->io_tree; | |
6096 | return extent_readpages(tree, mapping, pages, nr_pages, | |
6097 | btrfs_get_extent); | |
6098 | } | |
6099 | static int __btrfs_releasepage(struct page *page, gfp_t gfp_flags) | |
6100 | { | |
6101 | struct extent_io_tree *tree; | |
6102 | struct extent_map_tree *map; | |
6103 | int ret; | |
6104 | ||
6105 | tree = &BTRFS_I(page->mapping->host)->io_tree; | |
6106 | map = &BTRFS_I(page->mapping->host)->extent_tree; | |
6107 | ret = try_release_extent_mapping(map, tree, page, gfp_flags); | |
6108 | if (ret == 1) { | |
6109 | ClearPagePrivate(page); | |
6110 | set_page_private(page, 0); | |
6111 | page_cache_release(page); | |
6112 | } | |
6113 | return ret; | |
6114 | } | |
6115 | ||
6116 | static int btrfs_releasepage(struct page *page, gfp_t gfp_flags) | |
6117 | { | |
6118 | if (PageWriteback(page) || PageDirty(page)) | |
6119 | return 0; | |
6120 | return __btrfs_releasepage(page, gfp_flags & GFP_NOFS); | |
6121 | } | |
6122 | ||
6123 | static void btrfs_invalidatepage(struct page *page, unsigned long offset) | |
6124 | { | |
6125 | struct extent_io_tree *tree; | |
6126 | struct btrfs_ordered_extent *ordered; | |
6127 | struct extent_state *cached_state = NULL; | |
6128 | u64 page_start = page_offset(page); | |
6129 | u64 page_end = page_start + PAGE_CACHE_SIZE - 1; | |
6130 | ||
6131 | ||
6132 | /* | |
6133 | * we have the page locked, so new writeback can't start, | |
6134 | * and the dirty bit won't be cleared while we are here. | |
6135 | * | |
6136 | * Wait for IO on this page so that we can safely clear | |
6137 | * the PagePrivate2 bit and do ordered accounting | |
6138 | */ | |
6139 | wait_on_page_writeback(page); | |
6140 | ||
6141 | tree = &BTRFS_I(page->mapping->host)->io_tree; | |
6142 | if (offset) { | |
6143 | btrfs_releasepage(page, GFP_NOFS); | |
6144 | return; | |
6145 | } | |
6146 | lock_extent_bits(tree, page_start, page_end, 0, &cached_state, | |
6147 | GFP_NOFS); | |
6148 | ordered = btrfs_lookup_ordered_extent(page->mapping->host, | |
6149 | page_offset(page)); | |
6150 | if (ordered) { | |
6151 | /* | |
6152 | * IO on this page will never be started, so we need | |
6153 | * to account for any ordered extents now | |
6154 | */ | |
6155 | clear_extent_bit(tree, page_start, page_end, | |
6156 | EXTENT_DIRTY | EXTENT_DELALLOC | | |
6157 | EXTENT_LOCKED | EXTENT_DO_ACCOUNTING, 1, 0, | |
6158 | &cached_state, GFP_NOFS); | |
6159 | /* | |
6160 | * whoever cleared the private bit is responsible | |
6161 | * for the finish_ordered_io | |
6162 | */ | |
6163 | if (TestClearPagePrivate2(page)) { | |
6164 | btrfs_finish_ordered_io(page->mapping->host, | |
6165 | page_start, page_end); | |
6166 | } | |
6167 | btrfs_put_ordered_extent(ordered); | |
6168 | cached_state = NULL; | |
6169 | lock_extent_bits(tree, page_start, page_end, 0, &cached_state, | |
6170 | GFP_NOFS); | |
6171 | } | |
6172 | clear_extent_bit(tree, page_start, page_end, | |
6173 | EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC | | |
6174 | EXTENT_DO_ACCOUNTING, 1, 1, &cached_state, GFP_NOFS); | |
6175 | __btrfs_releasepage(page, GFP_NOFS); | |
6176 | ||
6177 | ClearPageChecked(page); | |
6178 | if (PagePrivate(page)) { | |
6179 | ClearPagePrivate(page); | |
6180 | set_page_private(page, 0); | |
6181 | page_cache_release(page); | |
6182 | } | |
6183 | } | |
6184 | ||
6185 | /* | |
6186 | * btrfs_page_mkwrite() is not allowed to change the file size as it gets | |
6187 | * called from a page fault handler when a page is first dirtied. Hence we must | |
6188 | * be careful to check for EOF conditions here. We set the page up correctly | |
6189 | * for a written page which means we get ENOSPC checking when writing into | |
6190 | * holes and correct delalloc and unwritten extent mapping on filesystems that | |
6191 | * support these features. | |
6192 | * | |
6193 | * We are not allowed to take the i_mutex here so we have to play games to | |
6194 | * protect against truncate races as the page could now be beyond EOF. Because | |
6195 | * vmtruncate() writes the inode size before removing pages, once we have the | |
6196 | * page lock we can determine safely if the page is beyond EOF. If it is not | |
6197 | * beyond EOF, then the page is guaranteed safe against truncation until we | |
6198 | * unlock the page. | |
6199 | */ | |
6200 | int btrfs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) | |
6201 | { | |
6202 | struct page *page = vmf->page; | |
6203 | struct inode *inode = fdentry(vma->vm_file)->d_inode; | |
6204 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
6205 | struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; | |
6206 | struct btrfs_ordered_extent *ordered; | |
6207 | struct extent_state *cached_state = NULL; | |
6208 | char *kaddr; | |
6209 | unsigned long zero_start; | |
6210 | loff_t size; | |
6211 | int ret; | |
6212 | u64 page_start; | |
6213 | u64 page_end; | |
6214 | ||
6215 | ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE); | |
6216 | if (ret) { | |
6217 | if (ret == -ENOMEM) | |
6218 | ret = VM_FAULT_OOM; | |
6219 | else /* -ENOSPC, -EIO, etc */ | |
6220 | ret = VM_FAULT_SIGBUS; | |
6221 | goto out; | |
6222 | } | |
6223 | ||
6224 | ret = VM_FAULT_NOPAGE; /* make the VM retry the fault */ | |
6225 | again: | |
6226 | lock_page(page); | |
6227 | size = i_size_read(inode); | |
6228 | page_start = page_offset(page); | |
6229 | page_end = page_start + PAGE_CACHE_SIZE - 1; | |
6230 | ||
6231 | if ((page->mapping != inode->i_mapping) || | |
6232 | (page_start >= size)) { | |
6233 | /* page got truncated out from underneath us */ | |
6234 | goto out_unlock; | |
6235 | } | |
6236 | wait_on_page_writeback(page); | |
6237 | ||
6238 | lock_extent_bits(io_tree, page_start, page_end, 0, &cached_state, | |
6239 | GFP_NOFS); | |
6240 | set_page_extent_mapped(page); | |
6241 | ||
6242 | /* | |
6243 | * we can't set the delalloc bits if there are pending ordered | |
6244 | * extents. Drop our locks and wait for them to finish | |
6245 | */ | |
6246 | ordered = btrfs_lookup_ordered_extent(inode, page_start); | |
6247 | if (ordered) { | |
6248 | unlock_extent_cached(io_tree, page_start, page_end, | |
6249 | &cached_state, GFP_NOFS); | |
6250 | unlock_page(page); | |
6251 | btrfs_start_ordered_extent(inode, ordered, 1); | |
6252 | btrfs_put_ordered_extent(ordered); | |
6253 | goto again; | |
6254 | } | |
6255 | ||
6256 | /* | |
6257 | * XXX - page_mkwrite gets called every time the page is dirtied, even | |
6258 | * if it was already dirty, so for space accounting reasons we need to | |
6259 | * clear any delalloc bits for the range we are fixing to save. There | |
6260 | * is probably a better way to do this, but for now keep consistent with | |
6261 | * prepare_pages in the normal write path. | |
6262 | */ | |
6263 | clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, page_end, | |
6264 | EXTENT_DIRTY | EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING, | |
6265 | 0, 0, &cached_state, GFP_NOFS); | |
6266 | ||
6267 | ret = btrfs_set_extent_delalloc(inode, page_start, page_end, | |
6268 | &cached_state); | |
6269 | if (ret) { | |
6270 | unlock_extent_cached(io_tree, page_start, page_end, | |
6271 | &cached_state, GFP_NOFS); | |
6272 | ret = VM_FAULT_SIGBUS; | |
6273 | goto out_unlock; | |
6274 | } | |
6275 | ret = 0; | |
6276 | ||
6277 | /* page is wholly or partially inside EOF */ | |
6278 | if (page_start + PAGE_CACHE_SIZE > size) | |
6279 | zero_start = size & ~PAGE_CACHE_MASK; | |
6280 | else | |
6281 | zero_start = PAGE_CACHE_SIZE; | |
6282 | ||
6283 | if (zero_start != PAGE_CACHE_SIZE) { | |
6284 | kaddr = kmap(page); | |
6285 | memset(kaddr + zero_start, 0, PAGE_CACHE_SIZE - zero_start); | |
6286 | flush_dcache_page(page); | |
6287 | kunmap(page); | |
6288 | } | |
6289 | ClearPageChecked(page); | |
6290 | set_page_dirty(page); | |
6291 | SetPageUptodate(page); | |
6292 | ||
6293 | BTRFS_I(inode)->last_trans = root->fs_info->generation; | |
6294 | BTRFS_I(inode)->last_sub_trans = BTRFS_I(inode)->root->log_transid; | |
6295 | ||
6296 | unlock_extent_cached(io_tree, page_start, page_end, &cached_state, GFP_NOFS); | |
6297 | ||
6298 | out_unlock: | |
6299 | if (!ret) | |
6300 | return VM_FAULT_LOCKED; | |
6301 | unlock_page(page); | |
6302 | btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE); | |
6303 | out: | |
6304 | return ret; | |
6305 | } | |
6306 | ||
6307 | static void btrfs_truncate(struct inode *inode) | |
6308 | { | |
6309 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
6310 | int ret; | |
6311 | struct btrfs_trans_handle *trans; | |
6312 | unsigned long nr; | |
6313 | u64 mask = root->sectorsize - 1; | |
6314 | ||
6315 | if (!S_ISREG(inode->i_mode)) { | |
6316 | WARN_ON(1); | |
6317 | return; | |
6318 | } | |
6319 | ||
6320 | ret = btrfs_truncate_page(inode->i_mapping, inode->i_size); | |
6321 | if (ret) | |
6322 | return; | |
6323 | ||
6324 | btrfs_wait_ordered_range(inode, inode->i_size & (~mask), (u64)-1); | |
6325 | btrfs_ordered_update_i_size(inode, inode->i_size, NULL); | |
6326 | ||
6327 | trans = btrfs_start_transaction(root, 0); | |
6328 | BUG_ON(IS_ERR(trans)); | |
6329 | btrfs_set_trans_block_group(trans, inode); | |
6330 | trans->block_rsv = root->orphan_block_rsv; | |
6331 | ||
6332 | /* | |
6333 | * setattr is responsible for setting the ordered_data_close flag, | |
6334 | * but that is only tested during the last file release. That | |
6335 | * could happen well after the next commit, leaving a great big | |
6336 | * window where new writes may get lost if someone chooses to write | |
6337 | * to this file after truncating to zero | |
6338 | * | |
6339 | * The inode doesn't have any dirty data here, and so if we commit | |
6340 | * this is a noop. If someone immediately starts writing to the inode | |
6341 | * it is very likely we'll catch some of their writes in this | |
6342 | * transaction, and the commit will find this file on the ordered | |
6343 | * data list with good things to send down. | |
6344 | * | |
6345 | * This is a best effort solution, there is still a window where | |
6346 | * using truncate to replace the contents of the file will | |
6347 | * end up with a zero length file after a crash. | |
6348 | */ | |
6349 | if (inode->i_size == 0 && BTRFS_I(inode)->ordered_data_close) | |
6350 | btrfs_add_ordered_operation(trans, root, inode); | |
6351 | ||
6352 | while (1) { | |
6353 | if (!trans) { | |
6354 | trans = btrfs_start_transaction(root, 0); | |
6355 | BUG_ON(IS_ERR(trans)); | |
6356 | btrfs_set_trans_block_group(trans, inode); | |
6357 | trans->block_rsv = root->orphan_block_rsv; | |
6358 | } | |
6359 | ||
6360 | ret = btrfs_block_rsv_check(trans, root, | |
6361 | root->orphan_block_rsv, 0, 5); | |
6362 | if (ret) { | |
6363 | BUG_ON(ret != -EAGAIN); | |
6364 | ret = btrfs_commit_transaction(trans, root); | |
6365 | BUG_ON(ret); | |
6366 | trans = NULL; | |
6367 | continue; | |
6368 | } | |
6369 | ||
6370 | ret = btrfs_truncate_inode_items(trans, root, inode, | |
6371 | inode->i_size, | |
6372 | BTRFS_EXTENT_DATA_KEY); | |
6373 | if (ret != -EAGAIN) | |
6374 | break; | |
6375 | ||
6376 | ret = btrfs_update_inode(trans, root, inode); | |
6377 | BUG_ON(ret); | |
6378 | ||
6379 | nr = trans->blocks_used; | |
6380 | btrfs_end_transaction(trans, root); | |
6381 | trans = NULL; | |
6382 | btrfs_btree_balance_dirty(root, nr); | |
6383 | } | |
6384 | ||
6385 | if (ret == 0 && inode->i_nlink > 0) { | |
6386 | ret = btrfs_orphan_del(trans, inode); | |
6387 | BUG_ON(ret); | |
6388 | } | |
6389 | ||
6390 | ret = btrfs_update_inode(trans, root, inode); | |
6391 | BUG_ON(ret); | |
6392 | ||
6393 | nr = trans->blocks_used; | |
6394 | ret = btrfs_end_transaction_throttle(trans, root); | |
6395 | BUG_ON(ret); | |
6396 | btrfs_btree_balance_dirty(root, nr); | |
6397 | } | |
6398 | ||
6399 | /* | |
6400 | * create a new subvolume directory/inode (helper for the ioctl). | |
6401 | */ | |
6402 | int btrfs_create_subvol_root(struct btrfs_trans_handle *trans, | |
6403 | struct btrfs_root *new_root, | |
6404 | u64 new_dirid, u64 alloc_hint) | |
6405 | { | |
6406 | struct inode *inode; | |
6407 | int err; | |
6408 | u64 index = 0; | |
6409 | ||
6410 | inode = btrfs_new_inode(trans, new_root, NULL, "..", 2, new_dirid, | |
6411 | new_dirid, alloc_hint, S_IFDIR | 0700, &index); | |
6412 | if (IS_ERR(inode)) | |
6413 | return PTR_ERR(inode); | |
6414 | inode->i_op = &btrfs_dir_inode_operations; | |
6415 | inode->i_fop = &btrfs_dir_file_operations; | |
6416 | ||
6417 | inode->i_nlink = 1; | |
6418 | btrfs_i_size_write(inode, 0); | |
6419 | ||
6420 | err = btrfs_update_inode(trans, new_root, inode); | |
6421 | BUG_ON(err); | |
6422 | ||
6423 | iput(inode); | |
6424 | return 0; | |
6425 | } | |
6426 | ||
6427 | /* helper function for file defrag and space balancing. This | |
6428 | * forces readahead on a given range of bytes in an inode | |
6429 | */ | |
6430 | unsigned long btrfs_force_ra(struct address_space *mapping, | |
6431 | struct file_ra_state *ra, struct file *file, | |
6432 | pgoff_t offset, pgoff_t last_index) | |
6433 | { | |
6434 | pgoff_t req_size = last_index - offset + 1; | |
6435 | ||
6436 | page_cache_sync_readahead(mapping, ra, file, offset, req_size); | |
6437 | return offset + req_size; | |
6438 | } | |
6439 | ||
6440 | struct inode *btrfs_alloc_inode(struct super_block *sb) | |
6441 | { | |
6442 | struct btrfs_inode *ei; | |
6443 | struct inode *inode; | |
6444 | ||
6445 | ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS); | |
6446 | if (!ei) | |
6447 | return NULL; | |
6448 | ||
6449 | ei->root = NULL; | |
6450 | ei->space_info = NULL; | |
6451 | ei->generation = 0; | |
6452 | ei->sequence = 0; | |
6453 | ei->last_trans = 0; | |
6454 | ei->last_sub_trans = 0; | |
6455 | ei->logged_trans = 0; | |
6456 | ei->delalloc_bytes = 0; | |
6457 | ei->reserved_bytes = 0; | |
6458 | ei->disk_i_size = 0; | |
6459 | ei->flags = 0; | |
6460 | ei->index_cnt = (u64)-1; | |
6461 | ei->last_unlink_trans = 0; | |
6462 | ||
6463 | spin_lock_init(&ei->accounting_lock); | |
6464 | atomic_set(&ei->outstanding_extents, 0); | |
6465 | ei->reserved_extents = 0; | |
6466 | ||
6467 | ei->ordered_data_close = 0; | |
6468 | ei->orphan_meta_reserved = 0; | |
6469 | ei->dummy_inode = 0; | |
6470 | ei->force_compress = 0; | |
6471 | ||
6472 | inode = &ei->vfs_inode; | |
6473 | extent_map_tree_init(&ei->extent_tree, GFP_NOFS); | |
6474 | extent_io_tree_init(&ei->io_tree, &inode->i_data, GFP_NOFS); | |
6475 | extent_io_tree_init(&ei->io_failure_tree, &inode->i_data, GFP_NOFS); | |
6476 | mutex_init(&ei->log_mutex); | |
6477 | btrfs_ordered_inode_tree_init(&ei->ordered_tree); | |
6478 | INIT_LIST_HEAD(&ei->i_orphan); | |
6479 | INIT_LIST_HEAD(&ei->delalloc_inodes); | |
6480 | INIT_LIST_HEAD(&ei->ordered_operations); | |
6481 | RB_CLEAR_NODE(&ei->rb_node); | |
6482 | ||
6483 | return inode; | |
6484 | } | |
6485 | ||
6486 | void btrfs_destroy_inode(struct inode *inode) | |
6487 | { | |
6488 | struct btrfs_ordered_extent *ordered; | |
6489 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
6490 | ||
6491 | WARN_ON(!list_empty(&inode->i_dentry)); | |
6492 | WARN_ON(inode->i_data.nrpages); | |
6493 | WARN_ON(atomic_read(&BTRFS_I(inode)->outstanding_extents)); | |
6494 | WARN_ON(BTRFS_I(inode)->reserved_extents); | |
6495 | ||
6496 | /* | |
6497 | * This can happen where we create an inode, but somebody else also | |
6498 | * created the same inode and we need to destroy the one we already | |
6499 | * created. | |
6500 | */ | |
6501 | if (!root) | |
6502 | goto free; | |
6503 | ||
6504 | /* | |
6505 | * Make sure we're properly removed from the ordered operation | |
6506 | * lists. | |
6507 | */ | |
6508 | smp_mb(); | |
6509 | if (!list_empty(&BTRFS_I(inode)->ordered_operations)) { | |
6510 | spin_lock(&root->fs_info->ordered_extent_lock); | |
6511 | list_del_init(&BTRFS_I(inode)->ordered_operations); | |
6512 | spin_unlock(&root->fs_info->ordered_extent_lock); | |
6513 | } | |
6514 | ||
6515 | if (root == root->fs_info->tree_root) { | |
6516 | struct btrfs_block_group_cache *block_group; | |
6517 | ||
6518 | block_group = btrfs_lookup_block_group(root->fs_info, | |
6519 | BTRFS_I(inode)->block_group); | |
6520 | if (block_group && block_group->inode == inode) { | |
6521 | spin_lock(&block_group->lock); | |
6522 | block_group->inode = NULL; | |
6523 | spin_unlock(&block_group->lock); | |
6524 | btrfs_put_block_group(block_group); | |
6525 | } else if (block_group) { | |
6526 | btrfs_put_block_group(block_group); | |
6527 | } | |
6528 | } | |
6529 | ||
6530 | spin_lock(&root->orphan_lock); | |
6531 | if (!list_empty(&BTRFS_I(inode)->i_orphan)) { | |
6532 | printk(KERN_INFO "BTRFS: inode %lu still on the orphan list\n", | |
6533 | inode->i_ino); | |
6534 | list_del_init(&BTRFS_I(inode)->i_orphan); | |
6535 | } | |
6536 | spin_unlock(&root->orphan_lock); | |
6537 | ||
6538 | while (1) { | |
6539 | ordered = btrfs_lookup_first_ordered_extent(inode, (u64)-1); | |
6540 | if (!ordered) | |
6541 | break; | |
6542 | else { | |
6543 | printk(KERN_ERR "btrfs found ordered " | |
6544 | "extent %llu %llu on inode cleanup\n", | |
6545 | (unsigned long long)ordered->file_offset, | |
6546 | (unsigned long long)ordered->len); | |
6547 | btrfs_remove_ordered_extent(inode, ordered); | |
6548 | btrfs_put_ordered_extent(ordered); | |
6549 | btrfs_put_ordered_extent(ordered); | |
6550 | } | |
6551 | } | |
6552 | inode_tree_del(inode); | |
6553 | btrfs_drop_extent_cache(inode, 0, (u64)-1, 0); | |
6554 | free: | |
6555 | kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode)); | |
6556 | } | |
6557 | ||
6558 | int btrfs_drop_inode(struct inode *inode) | |
6559 | { | |
6560 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
6561 | ||
6562 | if (btrfs_root_refs(&root->root_item) == 0 && | |
6563 | root != root->fs_info->tree_root) | |
6564 | return 1; | |
6565 | else | |
6566 | return generic_drop_inode(inode); | |
6567 | } | |
6568 | ||
6569 | static void init_once(void *foo) | |
6570 | { | |
6571 | struct btrfs_inode *ei = (struct btrfs_inode *) foo; | |
6572 | ||
6573 | inode_init_once(&ei->vfs_inode); | |
6574 | } | |
6575 | ||
6576 | void btrfs_destroy_cachep(void) | |
6577 | { | |
6578 | if (btrfs_inode_cachep) | |
6579 | kmem_cache_destroy(btrfs_inode_cachep); | |
6580 | if (btrfs_trans_handle_cachep) | |
6581 | kmem_cache_destroy(btrfs_trans_handle_cachep); | |
6582 | if (btrfs_transaction_cachep) | |
6583 | kmem_cache_destroy(btrfs_transaction_cachep); | |
6584 | if (btrfs_path_cachep) | |
6585 | kmem_cache_destroy(btrfs_path_cachep); | |
6586 | } | |
6587 | ||
6588 | int btrfs_init_cachep(void) | |
6589 | { | |
6590 | btrfs_inode_cachep = kmem_cache_create("btrfs_inode_cache", | |
6591 | sizeof(struct btrfs_inode), 0, | |
6592 | SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, init_once); | |
6593 | if (!btrfs_inode_cachep) | |
6594 | goto fail; | |
6595 | ||
6596 | btrfs_trans_handle_cachep = kmem_cache_create("btrfs_trans_handle_cache", | |
6597 | sizeof(struct btrfs_trans_handle), 0, | |
6598 | SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL); | |
6599 | if (!btrfs_trans_handle_cachep) | |
6600 | goto fail; | |
6601 | ||
6602 | btrfs_transaction_cachep = kmem_cache_create("btrfs_transaction_cache", | |
6603 | sizeof(struct btrfs_transaction), 0, | |
6604 | SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL); | |
6605 | if (!btrfs_transaction_cachep) | |
6606 | goto fail; | |
6607 | ||
6608 | btrfs_path_cachep = kmem_cache_create("btrfs_path_cache", | |
6609 | sizeof(struct btrfs_path), 0, | |
6610 | SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL); | |
6611 | if (!btrfs_path_cachep) | |
6612 | goto fail; | |
6613 | ||
6614 | return 0; | |
6615 | fail: | |
6616 | btrfs_destroy_cachep(); | |
6617 | return -ENOMEM; | |
6618 | } | |
6619 | ||
6620 | static int btrfs_getattr(struct vfsmount *mnt, | |
6621 | struct dentry *dentry, struct kstat *stat) | |
6622 | { | |
6623 | struct inode *inode = dentry->d_inode; | |
6624 | generic_fillattr(inode, stat); | |
6625 | stat->dev = BTRFS_I(inode)->root->anon_super.s_dev; | |
6626 | stat->blksize = PAGE_CACHE_SIZE; | |
6627 | stat->blocks = (inode_get_bytes(inode) + | |
6628 | BTRFS_I(inode)->delalloc_bytes) >> 9; | |
6629 | return 0; | |
6630 | } | |
6631 | ||
6632 | static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry, | |
6633 | struct inode *new_dir, struct dentry *new_dentry) | |
6634 | { | |
6635 | struct btrfs_trans_handle *trans; | |
6636 | struct btrfs_root *root = BTRFS_I(old_dir)->root; | |
6637 | struct btrfs_root *dest = BTRFS_I(new_dir)->root; | |
6638 | struct inode *new_inode = new_dentry->d_inode; | |
6639 | struct inode *old_inode = old_dentry->d_inode; | |
6640 | struct timespec ctime = CURRENT_TIME; | |
6641 | u64 index = 0; | |
6642 | u64 root_objectid; | |
6643 | int ret; | |
6644 | ||
6645 | if (new_dir->i_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID) | |
6646 | return -EPERM; | |
6647 | ||
6648 | /* we only allow rename subvolume link between subvolumes */ | |
6649 | if (old_inode->i_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest) | |
6650 | return -EXDEV; | |
6651 | ||
6652 | if (old_inode->i_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID || | |
6653 | (new_inode && new_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)) | |
6654 | return -ENOTEMPTY; | |
6655 | ||
6656 | if (S_ISDIR(old_inode->i_mode) && new_inode && | |
6657 | new_inode->i_size > BTRFS_EMPTY_DIR_SIZE) | |
6658 | return -ENOTEMPTY; | |
6659 | /* | |
6660 | * we're using rename to replace one file with another. | |
6661 | * and the replacement file is large. Start IO on it now so | |
6662 | * we don't add too much work to the end of the transaction | |
6663 | */ | |
6664 | if (new_inode && S_ISREG(old_inode->i_mode) && new_inode->i_size && | |
6665 | old_inode->i_size > BTRFS_ORDERED_OPERATIONS_FLUSH_LIMIT) | |
6666 | filemap_flush(old_inode->i_mapping); | |
6667 | ||
6668 | /* close the racy window with snapshot create/destroy ioctl */ | |
6669 | if (old_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID) | |
6670 | down_read(&root->fs_info->subvol_sem); | |
6671 | /* | |
6672 | * We want to reserve the absolute worst case amount of items. So if | |
6673 | * both inodes are subvols and we need to unlink them then that would | |
6674 | * require 4 item modifications, but if they are both normal inodes it | |
6675 | * would require 5 item modifications, so we'll assume their normal | |
6676 | * inodes. So 5 * 2 is 10, plus 1 for the new link, so 11 total items | |
6677 | * should cover the worst case number of items we'll modify. | |
6678 | */ | |
6679 | trans = btrfs_start_transaction(root, 20); | |
6680 | if (IS_ERR(trans)) | |
6681 | return PTR_ERR(trans); | |
6682 | ||
6683 | btrfs_set_trans_block_group(trans, new_dir); | |
6684 | ||
6685 | if (dest != root) | |
6686 | btrfs_record_root_in_trans(trans, dest); | |
6687 | ||
6688 | ret = btrfs_set_inode_index(new_dir, &index); | |
6689 | if (ret) | |
6690 | goto out_fail; | |
6691 | ||
6692 | if (unlikely(old_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)) { | |
6693 | /* force full log commit if subvolume involved. */ | |
6694 | root->fs_info->last_trans_log_full_commit = trans->transid; | |
6695 | } else { | |
6696 | ret = btrfs_insert_inode_ref(trans, dest, | |
6697 | new_dentry->d_name.name, | |
6698 | new_dentry->d_name.len, | |
6699 | old_inode->i_ino, | |
6700 | new_dir->i_ino, index); | |
6701 | if (ret) | |
6702 | goto out_fail; | |
6703 | /* | |
6704 | * this is an ugly little race, but the rename is required | |
6705 | * to make sure that if we crash, the inode is either at the | |
6706 | * old name or the new one. pinning the log transaction lets | |
6707 | * us make sure we don't allow a log commit to come in after | |
6708 | * we unlink the name but before we add the new name back in. | |
6709 | */ | |
6710 | btrfs_pin_log_trans(root); | |
6711 | } | |
6712 | /* | |
6713 | * make sure the inode gets flushed if it is replacing | |
6714 | * something. | |
6715 | */ | |
6716 | if (new_inode && new_inode->i_size && | |
6717 | old_inode && S_ISREG(old_inode->i_mode)) { | |
6718 | btrfs_add_ordered_operation(trans, root, old_inode); | |
6719 | } | |
6720 | ||
6721 | old_dir->i_ctime = old_dir->i_mtime = ctime; | |
6722 | new_dir->i_ctime = new_dir->i_mtime = ctime; | |
6723 | old_inode->i_ctime = ctime; | |
6724 | ||
6725 | if (old_dentry->d_parent != new_dentry->d_parent) | |
6726 | btrfs_record_unlink_dir(trans, old_dir, old_inode, 1); | |
6727 | ||
6728 | if (unlikely(old_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)) { | |
6729 | root_objectid = BTRFS_I(old_inode)->root->root_key.objectid; | |
6730 | ret = btrfs_unlink_subvol(trans, root, old_dir, root_objectid, | |
6731 | old_dentry->d_name.name, | |
6732 | old_dentry->d_name.len); | |
6733 | } else { | |
6734 | btrfs_inc_nlink(old_dentry->d_inode); | |
6735 | ret = btrfs_unlink_inode(trans, root, old_dir, | |
6736 | old_dentry->d_inode, | |
6737 | old_dentry->d_name.name, | |
6738 | old_dentry->d_name.len); | |
6739 | } | |
6740 | BUG_ON(ret); | |
6741 | ||
6742 | if (new_inode) { | |
6743 | new_inode->i_ctime = CURRENT_TIME; | |
6744 | if (unlikely(new_inode->i_ino == | |
6745 | BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) { | |
6746 | root_objectid = BTRFS_I(new_inode)->location.objectid; | |
6747 | ret = btrfs_unlink_subvol(trans, dest, new_dir, | |
6748 | root_objectid, | |
6749 | new_dentry->d_name.name, | |
6750 | new_dentry->d_name.len); | |
6751 | BUG_ON(new_inode->i_nlink == 0); | |
6752 | } else { | |
6753 | ret = btrfs_unlink_inode(trans, dest, new_dir, | |
6754 | new_dentry->d_inode, | |
6755 | new_dentry->d_name.name, | |
6756 | new_dentry->d_name.len); | |
6757 | } | |
6758 | BUG_ON(ret); | |
6759 | if (new_inode->i_nlink == 0) { | |
6760 | ret = btrfs_orphan_add(trans, new_dentry->d_inode); | |
6761 | BUG_ON(ret); | |
6762 | } | |
6763 | } | |
6764 | ||
6765 | ret = btrfs_add_link(trans, new_dir, old_inode, | |
6766 | new_dentry->d_name.name, | |
6767 | new_dentry->d_name.len, 0, index); | |
6768 | BUG_ON(ret); | |
6769 | ||
6770 | if (old_inode->i_ino != BTRFS_FIRST_FREE_OBJECTID) { | |
6771 | btrfs_log_new_name(trans, old_inode, old_dir, | |
6772 | new_dentry->d_parent); | |
6773 | btrfs_end_log_trans(root); | |
6774 | } | |
6775 | out_fail: | |
6776 | btrfs_end_transaction_throttle(trans, root); | |
6777 | ||
6778 | if (old_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID) | |
6779 | up_read(&root->fs_info->subvol_sem); | |
6780 | ||
6781 | return ret; | |
6782 | } | |
6783 | ||
6784 | /* | |
6785 | * some fairly slow code that needs optimization. This walks the list | |
6786 | * of all the inodes with pending delalloc and forces them to disk. | |
6787 | */ | |
6788 | int btrfs_start_delalloc_inodes(struct btrfs_root *root, int delay_iput) | |
6789 | { | |
6790 | struct list_head *head = &root->fs_info->delalloc_inodes; | |
6791 | struct btrfs_inode *binode; | |
6792 | struct inode *inode; | |
6793 | ||
6794 | if (root->fs_info->sb->s_flags & MS_RDONLY) | |
6795 | return -EROFS; | |
6796 | ||
6797 | spin_lock(&root->fs_info->delalloc_lock); | |
6798 | while (!list_empty(head)) { | |
6799 | binode = list_entry(head->next, struct btrfs_inode, | |
6800 | delalloc_inodes); | |
6801 | inode = igrab(&binode->vfs_inode); | |
6802 | if (!inode) | |
6803 | list_del_init(&binode->delalloc_inodes); | |
6804 | spin_unlock(&root->fs_info->delalloc_lock); | |
6805 | if (inode) { | |
6806 | filemap_flush(inode->i_mapping); | |
6807 | if (delay_iput) | |
6808 | btrfs_add_delayed_iput(inode); | |
6809 | else | |
6810 | iput(inode); | |
6811 | } | |
6812 | cond_resched(); | |
6813 | spin_lock(&root->fs_info->delalloc_lock); | |
6814 | } | |
6815 | spin_unlock(&root->fs_info->delalloc_lock); | |
6816 | ||
6817 | /* the filemap_flush will queue IO into the worker threads, but | |
6818 | * we have to make sure the IO is actually started and that | |
6819 | * ordered extents get created before we return | |
6820 | */ | |
6821 | atomic_inc(&root->fs_info->async_submit_draining); | |
6822 | while (atomic_read(&root->fs_info->nr_async_submits) || | |
6823 | atomic_read(&root->fs_info->async_delalloc_pages)) { | |
6824 | wait_event(root->fs_info->async_submit_wait, | |
6825 | (atomic_read(&root->fs_info->nr_async_submits) == 0 && | |
6826 | atomic_read(&root->fs_info->async_delalloc_pages) == 0)); | |
6827 | } | |
6828 | atomic_dec(&root->fs_info->async_submit_draining); | |
6829 | return 0; | |
6830 | } | |
6831 | ||
6832 | int btrfs_start_one_delalloc_inode(struct btrfs_root *root, int delay_iput, | |
6833 | int sync) | |
6834 | { | |
6835 | struct btrfs_inode *binode; | |
6836 | struct inode *inode = NULL; | |
6837 | ||
6838 | spin_lock(&root->fs_info->delalloc_lock); | |
6839 | while (!list_empty(&root->fs_info->delalloc_inodes)) { | |
6840 | binode = list_entry(root->fs_info->delalloc_inodes.next, | |
6841 | struct btrfs_inode, delalloc_inodes); | |
6842 | inode = igrab(&binode->vfs_inode); | |
6843 | if (inode) { | |
6844 | list_move_tail(&binode->delalloc_inodes, | |
6845 | &root->fs_info->delalloc_inodes); | |
6846 | break; | |
6847 | } | |
6848 | ||
6849 | list_del_init(&binode->delalloc_inodes); | |
6850 | cond_resched_lock(&root->fs_info->delalloc_lock); | |
6851 | } | |
6852 | spin_unlock(&root->fs_info->delalloc_lock); | |
6853 | ||
6854 | if (inode) { | |
6855 | if (sync) { | |
6856 | filemap_write_and_wait(inode->i_mapping); | |
6857 | /* | |
6858 | * We have to do this because compression doesn't | |
6859 | * actually set PG_writeback until it submits the pages | |
6860 | * for IO, which happens in an async thread, so we could | |
6861 | * race and not actually wait for any writeback pages | |
6862 | * because they've not been submitted yet. Technically | |
6863 | * this could still be the case for the ordered stuff | |
6864 | * since the async thread may not have started to do its | |
6865 | * work yet. If this becomes the case then we need to | |
6866 | * figure out a way to make sure that in writepage we | |
6867 | * wait for any async pages to be submitted before | |
6868 | * returning so that fdatawait does what its supposed to | |
6869 | * do. | |
6870 | */ | |
6871 | btrfs_wait_ordered_range(inode, 0, (u64)-1); | |
6872 | } else { | |
6873 | filemap_flush(inode->i_mapping); | |
6874 | } | |
6875 | if (delay_iput) | |
6876 | btrfs_add_delayed_iput(inode); | |
6877 | else | |
6878 | iput(inode); | |
6879 | return 1; | |
6880 | } | |
6881 | return 0; | |
6882 | } | |
6883 | ||
6884 | static int btrfs_symlink(struct inode *dir, struct dentry *dentry, | |
6885 | const char *symname) | |
6886 | { | |
6887 | struct btrfs_trans_handle *trans; | |
6888 | struct btrfs_root *root = BTRFS_I(dir)->root; | |
6889 | struct btrfs_path *path; | |
6890 | struct btrfs_key key; | |
6891 | struct inode *inode = NULL; | |
6892 | int err; | |
6893 | int drop_inode = 0; | |
6894 | u64 objectid; | |
6895 | u64 index = 0 ; | |
6896 | int name_len; | |
6897 | int datasize; | |
6898 | unsigned long ptr; | |
6899 | struct btrfs_file_extent_item *ei; | |
6900 | struct extent_buffer *leaf; | |
6901 | unsigned long nr = 0; | |
6902 | ||
6903 | name_len = strlen(symname) + 1; | |
6904 | if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(root)) | |
6905 | return -ENAMETOOLONG; | |
6906 | ||
6907 | err = btrfs_find_free_objectid(NULL, root, dir->i_ino, &objectid); | |
6908 | if (err) | |
6909 | return err; | |
6910 | /* | |
6911 | * 2 items for inode item and ref | |
6912 | * 2 items for dir items | |
6913 | * 1 item for xattr if selinux is on | |
6914 | */ | |
6915 | trans = btrfs_start_transaction(root, 5); | |
6916 | if (IS_ERR(trans)) | |
6917 | return PTR_ERR(trans); | |
6918 | ||
6919 | btrfs_set_trans_block_group(trans, dir); | |
6920 | ||
6921 | inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name, | |
6922 | dentry->d_name.len, | |
6923 | dentry->d_parent->d_inode->i_ino, objectid, | |
6924 | BTRFS_I(dir)->block_group, S_IFLNK|S_IRWXUGO, | |
6925 | &index); | |
6926 | err = PTR_ERR(inode); | |
6927 | if (IS_ERR(inode)) | |
6928 | goto out_unlock; | |
6929 | ||
6930 | err = btrfs_init_inode_security(trans, inode, dir); | |
6931 | if (err) { | |
6932 | drop_inode = 1; | |
6933 | goto out_unlock; | |
6934 | } | |
6935 | ||
6936 | btrfs_set_trans_block_group(trans, inode); | |
6937 | err = btrfs_add_nondir(trans, dentry, inode, 0, index); | |
6938 | if (err) | |
6939 | drop_inode = 1; | |
6940 | else { | |
6941 | inode->i_mapping->a_ops = &btrfs_aops; | |
6942 | inode->i_mapping->backing_dev_info = &root->fs_info->bdi; | |
6943 | inode->i_fop = &btrfs_file_operations; | |
6944 | inode->i_op = &btrfs_file_inode_operations; | |
6945 | BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; | |
6946 | } | |
6947 | btrfs_update_inode_block_group(trans, inode); | |
6948 | btrfs_update_inode_block_group(trans, dir); | |
6949 | if (drop_inode) | |
6950 | goto out_unlock; | |
6951 | ||
6952 | path = btrfs_alloc_path(); | |
6953 | BUG_ON(!path); | |
6954 | key.objectid = inode->i_ino; | |
6955 | key.offset = 0; | |
6956 | btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY); | |
6957 | datasize = btrfs_file_extent_calc_inline_size(name_len); | |
6958 | err = btrfs_insert_empty_item(trans, root, path, &key, | |
6959 | datasize); | |
6960 | if (err) { | |
6961 | drop_inode = 1; | |
6962 | goto out_unlock; | |
6963 | } | |
6964 | leaf = path->nodes[0]; | |
6965 | ei = btrfs_item_ptr(leaf, path->slots[0], | |
6966 | struct btrfs_file_extent_item); | |
6967 | btrfs_set_file_extent_generation(leaf, ei, trans->transid); | |
6968 | btrfs_set_file_extent_type(leaf, ei, | |
6969 | BTRFS_FILE_EXTENT_INLINE); | |
6970 | btrfs_set_file_extent_encryption(leaf, ei, 0); | |
6971 | btrfs_set_file_extent_compression(leaf, ei, 0); | |
6972 | btrfs_set_file_extent_other_encoding(leaf, ei, 0); | |
6973 | btrfs_set_file_extent_ram_bytes(leaf, ei, name_len); | |
6974 | ||
6975 | ptr = btrfs_file_extent_inline_start(ei); | |
6976 | write_extent_buffer(leaf, symname, ptr, name_len); | |
6977 | btrfs_mark_buffer_dirty(leaf); | |
6978 | btrfs_free_path(path); | |
6979 | ||
6980 | inode->i_op = &btrfs_symlink_inode_operations; | |
6981 | inode->i_mapping->a_ops = &btrfs_symlink_aops; | |
6982 | inode->i_mapping->backing_dev_info = &root->fs_info->bdi; | |
6983 | inode_set_bytes(inode, name_len); | |
6984 | btrfs_i_size_write(inode, name_len - 1); | |
6985 | err = btrfs_update_inode(trans, root, inode); | |
6986 | if (err) | |
6987 | drop_inode = 1; | |
6988 | ||
6989 | out_unlock: | |
6990 | nr = trans->blocks_used; | |
6991 | btrfs_end_transaction_throttle(trans, root); | |
6992 | if (drop_inode) { | |
6993 | inode_dec_link_count(inode); | |
6994 | iput(inode); | |
6995 | } | |
6996 | btrfs_btree_balance_dirty(root, nr); | |
6997 | return err; | |
6998 | } | |
6999 | ||
7000 | static int __btrfs_prealloc_file_range(struct inode *inode, int mode, | |
7001 | u64 start, u64 num_bytes, u64 min_size, | |
7002 | loff_t actual_len, u64 *alloc_hint, | |
7003 | struct btrfs_trans_handle *trans) | |
7004 | { | |
7005 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
7006 | struct btrfs_key ins; | |
7007 | u64 cur_offset = start; | |
7008 | int ret = 0; | |
7009 | bool own_trans = true; | |
7010 | ||
7011 | if (trans) | |
7012 | own_trans = false; | |
7013 | while (num_bytes > 0) { | |
7014 | if (own_trans) { | |
7015 | trans = btrfs_start_transaction(root, 3); | |
7016 | if (IS_ERR(trans)) { | |
7017 | ret = PTR_ERR(trans); | |
7018 | break; | |
7019 | } | |
7020 | } | |
7021 | ||
7022 | ret = btrfs_reserve_extent(trans, root, num_bytes, min_size, | |
7023 | 0, *alloc_hint, (u64)-1, &ins, 1); | |
7024 | if (ret) { | |
7025 | if (own_trans) | |
7026 | btrfs_end_transaction(trans, root); | |
7027 | break; | |
7028 | } | |
7029 | ||
7030 | ret = insert_reserved_file_extent(trans, inode, | |
7031 | cur_offset, ins.objectid, | |
7032 | ins.offset, ins.offset, | |
7033 | ins.offset, 0, 0, 0, | |
7034 | BTRFS_FILE_EXTENT_PREALLOC); | |
7035 | BUG_ON(ret); | |
7036 | btrfs_drop_extent_cache(inode, cur_offset, | |
7037 | cur_offset + ins.offset -1, 0); | |
7038 | ||
7039 | num_bytes -= ins.offset; | |
7040 | cur_offset += ins.offset; | |
7041 | *alloc_hint = ins.objectid + ins.offset; | |
7042 | ||
7043 | inode->i_ctime = CURRENT_TIME; | |
7044 | BTRFS_I(inode)->flags |= BTRFS_INODE_PREALLOC; | |
7045 | if (!(mode & FALLOC_FL_KEEP_SIZE) && | |
7046 | (actual_len > inode->i_size) && | |
7047 | (cur_offset > inode->i_size)) { | |
7048 | if (cur_offset > actual_len) | |
7049 | i_size_write(inode, actual_len); | |
7050 | else | |
7051 | i_size_write(inode, cur_offset); | |
7052 | i_size_write(inode, cur_offset); | |
7053 | btrfs_ordered_update_i_size(inode, cur_offset, NULL); | |
7054 | } | |
7055 | ||
7056 | ret = btrfs_update_inode(trans, root, inode); | |
7057 | BUG_ON(ret); | |
7058 | ||
7059 | if (own_trans) | |
7060 | btrfs_end_transaction(trans, root); | |
7061 | } | |
7062 | return ret; | |
7063 | } | |
7064 | ||
7065 | int btrfs_prealloc_file_range(struct inode *inode, int mode, | |
7066 | u64 start, u64 num_bytes, u64 min_size, | |
7067 | loff_t actual_len, u64 *alloc_hint) | |
7068 | { | |
7069 | return __btrfs_prealloc_file_range(inode, mode, start, num_bytes, | |
7070 | min_size, actual_len, alloc_hint, | |
7071 | NULL); | |
7072 | } | |
7073 | ||
7074 | int btrfs_prealloc_file_range_trans(struct inode *inode, | |
7075 | struct btrfs_trans_handle *trans, int mode, | |
7076 | u64 start, u64 num_bytes, u64 min_size, | |
7077 | loff_t actual_len, u64 *alloc_hint) | |
7078 | { | |
7079 | return __btrfs_prealloc_file_range(inode, mode, start, num_bytes, | |
7080 | min_size, actual_len, alloc_hint, trans); | |
7081 | } | |
7082 | ||
7083 | static long btrfs_fallocate(struct inode *inode, int mode, | |
7084 | loff_t offset, loff_t len) | |
7085 | { | |
7086 | struct extent_state *cached_state = NULL; | |
7087 | u64 cur_offset; | |
7088 | u64 last_byte; | |
7089 | u64 alloc_start; | |
7090 | u64 alloc_end; | |
7091 | u64 alloc_hint = 0; | |
7092 | u64 locked_end; | |
7093 | u64 mask = BTRFS_I(inode)->root->sectorsize - 1; | |
7094 | struct extent_map *em; | |
7095 | int ret; | |
7096 | ||
7097 | alloc_start = offset & ~mask; | |
7098 | alloc_end = (offset + len + mask) & ~mask; | |
7099 | ||
7100 | /* | |
7101 | * wait for ordered IO before we have any locks. We'll loop again | |
7102 | * below with the locks held. | |
7103 | */ | |
7104 | btrfs_wait_ordered_range(inode, alloc_start, alloc_end - alloc_start); | |
7105 | ||
7106 | mutex_lock(&inode->i_mutex); | |
7107 | if (alloc_start > inode->i_size) { | |
7108 | ret = btrfs_cont_expand(inode, alloc_start); | |
7109 | if (ret) | |
7110 | goto out; | |
7111 | } | |
7112 | ||
7113 | ret = btrfs_check_data_free_space(inode, alloc_end - alloc_start); | |
7114 | if (ret) | |
7115 | goto out; | |
7116 | ||
7117 | locked_end = alloc_end - 1; | |
7118 | while (1) { | |
7119 | struct btrfs_ordered_extent *ordered; | |
7120 | ||
7121 | /* the extent lock is ordered inside the running | |
7122 | * transaction | |
7123 | */ | |
7124 | lock_extent_bits(&BTRFS_I(inode)->io_tree, alloc_start, | |
7125 | locked_end, 0, &cached_state, GFP_NOFS); | |
7126 | ordered = btrfs_lookup_first_ordered_extent(inode, | |
7127 | alloc_end - 1); | |
7128 | if (ordered && | |
7129 | ordered->file_offset + ordered->len > alloc_start && | |
7130 | ordered->file_offset < alloc_end) { | |
7131 | btrfs_put_ordered_extent(ordered); | |
7132 | unlock_extent_cached(&BTRFS_I(inode)->io_tree, | |
7133 | alloc_start, locked_end, | |
7134 | &cached_state, GFP_NOFS); | |
7135 | /* | |
7136 | * we can't wait on the range with the transaction | |
7137 | * running or with the extent lock held | |
7138 | */ | |
7139 | btrfs_wait_ordered_range(inode, alloc_start, | |
7140 | alloc_end - alloc_start); | |
7141 | } else { | |
7142 | if (ordered) | |
7143 | btrfs_put_ordered_extent(ordered); | |
7144 | break; | |
7145 | } | |
7146 | } | |
7147 | ||
7148 | cur_offset = alloc_start; | |
7149 | while (1) { | |
7150 | em = btrfs_get_extent(inode, NULL, 0, cur_offset, | |
7151 | alloc_end - cur_offset, 0); | |
7152 | BUG_ON(IS_ERR(em) || !em); | |
7153 | last_byte = min(extent_map_end(em), alloc_end); | |
7154 | last_byte = (last_byte + mask) & ~mask; | |
7155 | if (em->block_start == EXTENT_MAP_HOLE || | |
7156 | (cur_offset >= inode->i_size && | |
7157 | !test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) { | |
7158 | ret = btrfs_prealloc_file_range(inode, mode, cur_offset, | |
7159 | last_byte - cur_offset, | |
7160 | 1 << inode->i_blkbits, | |
7161 | offset + len, | |
7162 | &alloc_hint); | |
7163 | if (ret < 0) { | |
7164 | free_extent_map(em); | |
7165 | break; | |
7166 | } | |
7167 | } | |
7168 | free_extent_map(em); | |
7169 | ||
7170 | cur_offset = last_byte; | |
7171 | if (cur_offset >= alloc_end) { | |
7172 | ret = 0; | |
7173 | break; | |
7174 | } | |
7175 | } | |
7176 | unlock_extent_cached(&BTRFS_I(inode)->io_tree, alloc_start, locked_end, | |
7177 | &cached_state, GFP_NOFS); | |
7178 | ||
7179 | btrfs_free_reserved_data_space(inode, alloc_end - alloc_start); | |
7180 | out: | |
7181 | mutex_unlock(&inode->i_mutex); | |
7182 | return ret; | |
7183 | } | |
7184 | ||
7185 | static int btrfs_set_page_dirty(struct page *page) | |
7186 | { | |
7187 | return __set_page_dirty_nobuffers(page); | |
7188 | } | |
7189 | ||
7190 | static int btrfs_permission(struct inode *inode, int mask) | |
7191 | { | |
7192 | if ((BTRFS_I(inode)->flags & BTRFS_INODE_READONLY) && (mask & MAY_WRITE)) | |
7193 | return -EACCES; | |
7194 | return generic_permission(inode, mask, btrfs_check_acl); | |
7195 | } | |
7196 | ||
7197 | static const struct inode_operations btrfs_dir_inode_operations = { | |
7198 | .getattr = btrfs_getattr, | |
7199 | .lookup = btrfs_lookup, | |
7200 | .create = btrfs_create, | |
7201 | .unlink = btrfs_unlink, | |
7202 | .link = btrfs_link, | |
7203 | .mkdir = btrfs_mkdir, | |
7204 | .rmdir = btrfs_rmdir, | |
7205 | .rename = btrfs_rename, | |
7206 | .symlink = btrfs_symlink, | |
7207 | .setattr = btrfs_setattr, | |
7208 | .mknod = btrfs_mknod, | |
7209 | .setxattr = btrfs_setxattr, | |
7210 | .getxattr = btrfs_getxattr, | |
7211 | .listxattr = btrfs_listxattr, | |
7212 | .removexattr = btrfs_removexattr, | |
7213 | .permission = btrfs_permission, | |
7214 | }; | |
7215 | static const struct inode_operations btrfs_dir_ro_inode_operations = { | |
7216 | .lookup = btrfs_lookup, | |
7217 | .permission = btrfs_permission, | |
7218 | }; | |
7219 | ||
7220 | static const struct file_operations btrfs_dir_file_operations = { | |
7221 | .llseek = generic_file_llseek, | |
7222 | .read = generic_read_dir, | |
7223 | .readdir = btrfs_real_readdir, | |
7224 | .unlocked_ioctl = btrfs_ioctl, | |
7225 | #ifdef CONFIG_COMPAT | |
7226 | .compat_ioctl = btrfs_ioctl, | |
7227 | #endif | |
7228 | .release = btrfs_release_file, | |
7229 | .fsync = btrfs_sync_file, | |
7230 | }; | |
7231 | ||
7232 | static struct extent_io_ops btrfs_extent_io_ops = { | |
7233 | .fill_delalloc = run_delalloc_range, | |
7234 | .submit_bio_hook = btrfs_submit_bio_hook, | |
7235 | .merge_bio_hook = btrfs_merge_bio_hook, | |
7236 | .readpage_end_io_hook = btrfs_readpage_end_io_hook, | |
7237 | .writepage_end_io_hook = btrfs_writepage_end_io_hook, | |
7238 | .writepage_start_hook = btrfs_writepage_start_hook, | |
7239 | .readpage_io_failed_hook = btrfs_io_failed_hook, | |
7240 | .set_bit_hook = btrfs_set_bit_hook, | |
7241 | .clear_bit_hook = btrfs_clear_bit_hook, | |
7242 | .merge_extent_hook = btrfs_merge_extent_hook, | |
7243 | .split_extent_hook = btrfs_split_extent_hook, | |
7244 | }; | |
7245 | ||
7246 | /* | |
7247 | * btrfs doesn't support the bmap operation because swapfiles | |
7248 | * use bmap to make a mapping of extents in the file. They assume | |
7249 | * these extents won't change over the life of the file and they | |
7250 | * use the bmap result to do IO directly to the drive. | |
7251 | * | |
7252 | * the btrfs bmap call would return logical addresses that aren't | |
7253 | * suitable for IO and they also will change frequently as COW | |
7254 | * operations happen. So, swapfile + btrfs == corruption. | |
7255 | * | |
7256 | * For now we're avoiding this by dropping bmap. | |
7257 | */ | |
7258 | static const struct address_space_operations btrfs_aops = { | |
7259 | .readpage = btrfs_readpage, | |
7260 | .writepage = btrfs_writepage, | |
7261 | .writepages = btrfs_writepages, | |
7262 | .readpages = btrfs_readpages, | |
7263 | .sync_page = block_sync_page, | |
7264 | .direct_IO = btrfs_direct_IO, | |
7265 | .invalidatepage = btrfs_invalidatepage, | |
7266 | .releasepage = btrfs_releasepage, | |
7267 | .set_page_dirty = btrfs_set_page_dirty, | |
7268 | .error_remove_page = generic_error_remove_page, | |
7269 | }; | |
7270 | ||
7271 | static const struct address_space_operations btrfs_symlink_aops = { | |
7272 | .readpage = btrfs_readpage, | |
7273 | .writepage = btrfs_writepage, | |
7274 | .invalidatepage = btrfs_invalidatepage, | |
7275 | .releasepage = btrfs_releasepage, | |
7276 | }; | |
7277 | ||
7278 | static const struct inode_operations btrfs_file_inode_operations = { | |
7279 | .truncate = btrfs_truncate, | |
7280 | .getattr = btrfs_getattr, | |
7281 | .setattr = btrfs_setattr, | |
7282 | .setxattr = btrfs_setxattr, | |
7283 | .getxattr = btrfs_getxattr, | |
7284 | .listxattr = btrfs_listxattr, | |
7285 | .removexattr = btrfs_removexattr, | |
7286 | .permission = btrfs_permission, | |
7287 | .fallocate = btrfs_fallocate, | |
7288 | .fiemap = btrfs_fiemap, | |
7289 | }; | |
7290 | static const struct inode_operations btrfs_special_inode_operations = { | |
7291 | .getattr = btrfs_getattr, | |
7292 | .setattr = btrfs_setattr, | |
7293 | .permission = btrfs_permission, | |
7294 | .setxattr = btrfs_setxattr, | |
7295 | .getxattr = btrfs_getxattr, | |
7296 | .listxattr = btrfs_listxattr, | |
7297 | .removexattr = btrfs_removexattr, | |
7298 | }; | |
7299 | static const struct inode_operations btrfs_symlink_inode_operations = { | |
7300 | .readlink = generic_readlink, | |
7301 | .follow_link = page_follow_link_light, | |
7302 | .put_link = page_put_link, | |
7303 | .getattr = btrfs_getattr, | |
7304 | .permission = btrfs_permission, | |
7305 | .setxattr = btrfs_setxattr, | |
7306 | .getxattr = btrfs_getxattr, | |
7307 | .listxattr = btrfs_listxattr, | |
7308 | .removexattr = btrfs_removexattr, | |
7309 | }; | |
7310 | ||
7311 | const struct dentry_operations btrfs_dentry_operations = { | |
7312 | .d_delete = btrfs_dentry_delete, | |
7313 | }; |