1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2007 Oracle. All rights reserved.
4 */
5
6 #include <linux/bio.h>
7 #include <linux/slab.h>
8 #include <linux/pagemap.h>
9 #include <linux/highmem.h>
10 #include <linux/sched/mm.h>
11 #include <crypto/hash.h>
12 #include "misc.h"
13 #include "ctree.h"
14 #include "disk-io.h"
15 #include "transaction.h"
16 #include "volumes.h"
17 #include "print-tree.h"
18 #include "compression.h"
19
20 #define __MAX_CSUM_ITEMS(r, size) ((unsigned long)(((BTRFS_LEAF_DATA_SIZE(r) - \
21 sizeof(struct btrfs_item) * 2) / \
22 size) - 1))
23
24 #define MAX_CSUM_ITEMS(r, size) (min_t(u32, __MAX_CSUM_ITEMS(r, size), \
25 PAGE_SIZE))
26
27 /**
28 * Set inode's size according to filesystem options
29 *
30 * @inode: inode we want to update the disk_i_size for
31 * @new_i_size: i_size we want to set to, 0 if we use i_size
32 *
33 * With NO_HOLES set this simply sets the disk_is_size to whatever i_size_read()
34 * returns as it is perfectly fine with a file that has holes without hole file
35 * extent items.
36 *
37 * However without NO_HOLES we need to only return the area that is contiguous
38 * from the 0 offset of the file. Otherwise we could end up adjust i_size up
39 * to an extent that has a gap in between.
40 *
41 * Finally new_i_size should only be set in the case of truncate where we're not
42 * ready to use i_size_read() as the limiter yet.
43 */
btrfs_inode_safe_disk_i_size_write(struct btrfs_inode * inode,u64 new_i_size)44 void btrfs_inode_safe_disk_i_size_write(struct btrfs_inode *inode, u64 new_i_size)
45 {
46 struct btrfs_fs_info *fs_info = inode->root->fs_info;
47 u64 start, end, i_size;
48 int ret;
49
50 i_size = new_i_size ?: i_size_read(&inode->vfs_inode);
51 if (btrfs_fs_incompat(fs_info, NO_HOLES)) {
52 inode->disk_i_size = i_size;
53 return;
54 }
55
56 spin_lock(&inode->lock);
57 ret = find_contiguous_extent_bit(&inode->file_extent_tree, 0, &start,
58 &end, EXTENT_DIRTY);
59 if (!ret && start == 0)
60 i_size = min(i_size, end + 1);
61 else
62 i_size = 0;
63 inode->disk_i_size = i_size;
64 spin_unlock(&inode->lock);
65 }
66
67 /**
68 * Mark range within a file as having a new extent inserted
69 *
70 * @inode: inode being modified
71 * @start: start file offset of the file extent we've inserted
72 * @len: logical length of the file extent item
73 *
74 * Call when we are inserting a new file extent where there was none before.
75 * Does not need to call this in the case where we're replacing an existing file
76 * extent, however if not sure it's fine to call this multiple times.
77 *
78 * The start and len must match the file extent item, so thus must be sectorsize
79 * aligned.
80 */
btrfs_inode_set_file_extent_range(struct btrfs_inode * inode,u64 start,u64 len)81 int btrfs_inode_set_file_extent_range(struct btrfs_inode *inode, u64 start,
82 u64 len)
83 {
84 if (len == 0)
85 return 0;
86
87 ASSERT(IS_ALIGNED(start + len, inode->root->fs_info->sectorsize));
88
89 if (btrfs_fs_incompat(inode->root->fs_info, NO_HOLES))
90 return 0;
91 return set_extent_bits(&inode->file_extent_tree, start, start + len - 1,
92 EXTENT_DIRTY);
93 }
94
95 /**
96 * Marks an inode range as not having a backing extent
97 *
98 * @inode: inode being modified
99 * @start: start file offset of the file extent we've inserted
100 * @len: logical length of the file extent item
101 *
102 * Called when we drop a file extent, for example when we truncate. Doesn't
103 * need to be called for cases where we're replacing a file extent, like when
104 * we've COWed a file extent.
105 *
106 * The start and len must match the file extent item, so thus must be sectorsize
107 * aligned.
108 */
btrfs_inode_clear_file_extent_range(struct btrfs_inode * inode,u64 start,u64 len)109 int btrfs_inode_clear_file_extent_range(struct btrfs_inode *inode, u64 start,
110 u64 len)
111 {
112 if (len == 0)
113 return 0;
114
115 ASSERT(IS_ALIGNED(start + len, inode->root->fs_info->sectorsize) ||
116 len == (u64)-1);
117
118 if (btrfs_fs_incompat(inode->root->fs_info, NO_HOLES))
119 return 0;
120 return clear_extent_bit(&inode->file_extent_tree, start,
121 start + len - 1, EXTENT_DIRTY, NULL);
122 }
123
max_ordered_sum_bytes(struct btrfs_fs_info * fs_info,u16 csum_size)124 static inline u32 max_ordered_sum_bytes(struct btrfs_fs_info *fs_info,
125 u16 csum_size)
126 {
127 u32 ncsums = (PAGE_SIZE - sizeof(struct btrfs_ordered_sum)) / csum_size;
128
129 return ncsums * fs_info->sectorsize;
130 }
131
132 /*
133 * Calculate the total size needed to allocate for an ordered sum structure
134 * spanning @bytes in the file.
135 */
btrfs_ordered_sum_size(struct btrfs_fs_info * fs_info,unsigned long bytes)136 static int btrfs_ordered_sum_size(struct btrfs_fs_info *fs_info, unsigned long bytes)
137 {
138 int num_sectors = (int)DIV_ROUND_UP(bytes, fs_info->sectorsize);
139
140 return sizeof(struct btrfs_ordered_sum) + num_sectors * fs_info->csum_size;
141 }
142
btrfs_insert_hole_extent(struct btrfs_trans_handle * trans,struct btrfs_root * root,u64 objectid,u64 pos,u64 num_bytes)143 int btrfs_insert_hole_extent(struct btrfs_trans_handle *trans,
144 struct btrfs_root *root,
145 u64 objectid, u64 pos, u64 num_bytes)
146 {
147 int ret = 0;
148 struct btrfs_file_extent_item *item;
149 struct btrfs_key file_key;
150 struct btrfs_path *path;
151 struct extent_buffer *leaf;
152
153 path = btrfs_alloc_path();
154 if (!path)
155 return -ENOMEM;
156 file_key.objectid = objectid;
157 file_key.offset = pos;
158 file_key.type = BTRFS_EXTENT_DATA_KEY;
159
160 ret = btrfs_insert_empty_item(trans, root, path, &file_key,
161 sizeof(*item));
162 if (ret < 0)
163 goto out;
164 BUG_ON(ret); /* Can't happen */
165 leaf = path->nodes[0];
166 item = btrfs_item_ptr(leaf, path->slots[0],
167 struct btrfs_file_extent_item);
168 btrfs_set_file_extent_disk_bytenr(leaf, item, 0);
169 btrfs_set_file_extent_disk_num_bytes(leaf, item, 0);
170 btrfs_set_file_extent_offset(leaf, item, 0);
171 btrfs_set_file_extent_num_bytes(leaf, item, num_bytes);
172 btrfs_set_file_extent_ram_bytes(leaf, item, num_bytes);
173 btrfs_set_file_extent_generation(leaf, item, trans->transid);
174 btrfs_set_file_extent_type(leaf, item, BTRFS_FILE_EXTENT_REG);
175 btrfs_set_file_extent_compression(leaf, item, 0);
176 btrfs_set_file_extent_encryption(leaf, item, 0);
177 btrfs_set_file_extent_other_encoding(leaf, item, 0);
178
179 btrfs_mark_buffer_dirty(leaf);
180 out:
181 btrfs_free_path(path);
182 return ret;
183 }
184
185 static struct btrfs_csum_item *
btrfs_lookup_csum(struct btrfs_trans_handle * trans,struct btrfs_root * root,struct btrfs_path * path,u64 bytenr,int cow)186 btrfs_lookup_csum(struct btrfs_trans_handle *trans,
187 struct btrfs_root *root,
188 struct btrfs_path *path,
189 u64 bytenr, int cow)
190 {
191 struct btrfs_fs_info *fs_info = root->fs_info;
192 int ret;
193 struct btrfs_key file_key;
194 struct btrfs_key found_key;
195 struct btrfs_csum_item *item;
196 struct extent_buffer *leaf;
197 u64 csum_offset = 0;
198 const u32 csum_size = fs_info->csum_size;
199 int csums_in_item;
200
201 file_key.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
202 file_key.offset = bytenr;
203 file_key.type = BTRFS_EXTENT_CSUM_KEY;
204 ret = btrfs_search_slot(trans, root, &file_key, path, 0, cow);
205 if (ret < 0)
206 goto fail;
207 leaf = path->nodes[0];
208 if (ret > 0) {
209 ret = 1;
210 if (path->slots[0] == 0)
211 goto fail;
212 path->slots[0]--;
213 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
214 if (found_key.type != BTRFS_EXTENT_CSUM_KEY)
215 goto fail;
216
217 csum_offset = (bytenr - found_key.offset) >>
218 fs_info->sectorsize_bits;
219 csums_in_item = btrfs_item_size(leaf, path->slots[0]);
220 csums_in_item /= csum_size;
221
222 if (csum_offset == csums_in_item) {
223 ret = -EFBIG;
224 goto fail;
225 } else if (csum_offset > csums_in_item) {
226 goto fail;
227 }
228 }
229 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_csum_item);
230 item = (struct btrfs_csum_item *)((unsigned char *)item +
231 csum_offset * csum_size);
232 return item;
233 fail:
234 if (ret > 0)
235 ret = -ENOENT;
236 return ERR_PTR(ret);
237 }
238
btrfs_lookup_file_extent(struct btrfs_trans_handle * trans,struct btrfs_root * root,struct btrfs_path * path,u64 objectid,u64 offset,int mod)239 int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans,
240 struct btrfs_root *root,
241 struct btrfs_path *path, u64 objectid,
242 u64 offset, int mod)
243 {
244 struct btrfs_key file_key;
245 int ins_len = mod < 0 ? -1 : 0;
246 int cow = mod != 0;
247
248 file_key.objectid = objectid;
249 file_key.offset = offset;
250 file_key.type = BTRFS_EXTENT_DATA_KEY;
251
252 return btrfs_search_slot(trans, root, &file_key, path, ins_len, cow);
253 }
254
255 /*
256 * Find checksums for logical bytenr range [disk_bytenr, disk_bytenr + len) and
257 * estore the result to @dst.
258 *
259 * Return >0 for the number of sectors we found.
260 * Return 0 for the range [disk_bytenr, disk_bytenr + sectorsize) has no csum
261 * for it. Caller may want to try next sector until one range is hit.
262 * Return <0 for fatal error.
263 */
search_csum_tree(struct btrfs_fs_info * fs_info,struct btrfs_path * path,u64 disk_bytenr,u64 len,u8 * dst)264 static int search_csum_tree(struct btrfs_fs_info *fs_info,
265 struct btrfs_path *path, u64 disk_bytenr,
266 u64 len, u8 *dst)
267 {
268 struct btrfs_root *csum_root;
269 struct btrfs_csum_item *item = NULL;
270 struct btrfs_key key;
271 const u32 sectorsize = fs_info->sectorsize;
272 const u32 csum_size = fs_info->csum_size;
273 u32 itemsize;
274 int ret;
275 u64 csum_start;
276 u64 csum_len;
277
278 ASSERT(IS_ALIGNED(disk_bytenr, sectorsize) &&
279 IS_ALIGNED(len, sectorsize));
280
281 /* Check if the current csum item covers disk_bytenr */
282 if (path->nodes[0]) {
283 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
284 struct btrfs_csum_item);
285 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
286 itemsize = btrfs_item_size(path->nodes[0], path->slots[0]);
287
288 csum_start = key.offset;
289 csum_len = (itemsize / csum_size) * sectorsize;
290
291 if (in_range(disk_bytenr, csum_start, csum_len))
292 goto found;
293 }
294
295 /* Current item doesn't contain the desired range, search again */
296 btrfs_release_path(path);
297 csum_root = btrfs_csum_root(fs_info, disk_bytenr);
298 item = btrfs_lookup_csum(NULL, csum_root, path, disk_bytenr, 0);
299 if (IS_ERR(item)) {
300 ret = PTR_ERR(item);
301 goto out;
302 }
303 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
304 itemsize = btrfs_item_size(path->nodes[0], path->slots[0]);
305
306 csum_start = key.offset;
307 csum_len = (itemsize / csum_size) * sectorsize;
308 ASSERT(in_range(disk_bytenr, csum_start, csum_len));
309
310 found:
311 ret = (min(csum_start + csum_len, disk_bytenr + len) -
312 disk_bytenr) >> fs_info->sectorsize_bits;
313 read_extent_buffer(path->nodes[0], dst, (unsigned long)item,
314 ret * csum_size);
315 out:
316 if (ret == -ENOENT || ret == -EFBIG)
317 ret = 0;
318 return ret;
319 }
320
321 /*
322 * Locate the file_offset of @cur_disk_bytenr of a @bio.
323 *
324 * Bio of btrfs represents read range of
325 * [bi_sector << 9, bi_sector << 9 + bi_size).
326 * Knowing this, we can iterate through each bvec to locate the page belong to
327 * @cur_disk_bytenr and get the file offset.
328 *
329 * @inode is used to determine if the bvec page really belongs to @inode.
330 *
331 * Return 0 if we can't find the file offset
332 * Return >0 if we find the file offset and restore it to @file_offset_ret
333 */
search_file_offset_in_bio(struct bio * bio,struct inode * inode,u64 disk_bytenr,u64 * file_offset_ret)334 static int search_file_offset_in_bio(struct bio *bio, struct inode *inode,
335 u64 disk_bytenr, u64 *file_offset_ret)
336 {
337 struct bvec_iter iter;
338 struct bio_vec bvec;
339 u64 cur = bio->bi_iter.bi_sector << SECTOR_SHIFT;
340 int ret = 0;
341
342 bio_for_each_segment(bvec, bio, iter) {
343 struct page *page = bvec.bv_page;
344
345 if (cur > disk_bytenr)
346 break;
347 if (cur + bvec.bv_len <= disk_bytenr) {
348 cur += bvec.bv_len;
349 continue;
350 }
351 ASSERT(in_range(disk_bytenr, cur, bvec.bv_len));
352 if (page->mapping && page->mapping->host &&
353 page->mapping->host == inode) {
354 ret = 1;
355 *file_offset_ret = page_offset(page) + bvec.bv_offset +
356 disk_bytenr - cur;
357 break;
358 }
359 }
360 return ret;
361 }
362
363 /**
364 * Lookup the checksum for the read bio in csum tree.
365 *
366 * @inode: inode that the bio is for.
367 * @bio: bio to look up.
368 * @dst: Buffer of size nblocks * btrfs_super_csum_size() used to return
369 * checksum (nblocks = bio->bi_iter.bi_size / fs_info->sectorsize). If
370 * NULL, the checksum buffer is allocated and returned in
371 * btrfs_bio(bio)->csum instead.
372 *
373 * Return: BLK_STS_RESOURCE if allocating memory fails, BLK_STS_OK otherwise.
374 */
btrfs_lookup_bio_sums(struct inode * inode,struct bio * bio,u8 * dst)375 blk_status_t btrfs_lookup_bio_sums(struct inode *inode, struct bio *bio, u8 *dst)
376 {
377 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
378 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
379 struct btrfs_bio *bbio = NULL;
380 struct btrfs_path *path;
381 const u32 sectorsize = fs_info->sectorsize;
382 const u32 csum_size = fs_info->csum_size;
383 u32 orig_len = bio->bi_iter.bi_size;
384 u64 orig_disk_bytenr = bio->bi_iter.bi_sector << SECTOR_SHIFT;
385 u64 cur_disk_bytenr;
386 u8 *csum;
387 const unsigned int nblocks = orig_len >> fs_info->sectorsize_bits;
388 int count = 0;
389 blk_status_t ret = BLK_STS_OK;
390
391 if ((BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM) ||
392 test_bit(BTRFS_FS_STATE_NO_CSUMS, &fs_info->fs_state))
393 return BLK_STS_OK;
394
395 /*
396 * This function is only called for read bio.
397 *
398 * This means two things:
399 * - All our csums should only be in csum tree
400 * No ordered extents csums, as ordered extents are only for write
401 * path.
402 * - No need to bother any other info from bvec
403 * Since we're looking up csums, the only important info is the
404 * disk_bytenr and the length, which can be extracted from bi_iter
405 * directly.
406 */
407 ASSERT(bio_op(bio) == REQ_OP_READ);
408 path = btrfs_alloc_path();
409 if (!path)
410 return BLK_STS_RESOURCE;
411
412 if (!dst) {
413 bbio = btrfs_bio(bio);
414
415 if (nblocks * csum_size > BTRFS_BIO_INLINE_CSUM_SIZE) {
416 bbio->csum = kmalloc_array(nblocks, csum_size, GFP_NOFS);
417 if (!bbio->csum) {
418 btrfs_free_path(path);
419 return BLK_STS_RESOURCE;
420 }
421 } else {
422 bbio->csum = bbio->csum_inline;
423 }
424 csum = bbio->csum;
425 } else {
426 csum = dst;
427 }
428
429 /*
430 * If requested number of sectors is larger than one leaf can contain,
431 * kick the readahead for csum tree.
432 */
433 if (nblocks > fs_info->csums_per_leaf)
434 path->reada = READA_FORWARD;
435
436 /*
437 * the free space stuff is only read when it hasn't been
438 * updated in the current transaction. So, we can safely
439 * read from the commit root and sidestep a nasty deadlock
440 * between reading the free space cache and updating the csum tree.
441 */
442 if (btrfs_is_free_space_inode(BTRFS_I(inode))) {
443 path->search_commit_root = 1;
444 path->skip_locking = 1;
445 }
446
447 for (cur_disk_bytenr = orig_disk_bytenr;
448 cur_disk_bytenr < orig_disk_bytenr + orig_len;
449 cur_disk_bytenr += (count * sectorsize)) {
450 u64 search_len = orig_disk_bytenr + orig_len - cur_disk_bytenr;
451 unsigned int sector_offset;
452 u8 *csum_dst;
453
454 /*
455 * Although both cur_disk_bytenr and orig_disk_bytenr is u64,
456 * we're calculating the offset to the bio start.
457 *
458 * Bio size is limited to UINT_MAX, thus unsigned int is large
459 * enough to contain the raw result, not to mention the right
460 * shifted result.
461 */
462 ASSERT(cur_disk_bytenr - orig_disk_bytenr < UINT_MAX);
463 sector_offset = (cur_disk_bytenr - orig_disk_bytenr) >>
464 fs_info->sectorsize_bits;
465 csum_dst = csum + sector_offset * csum_size;
466
467 count = search_csum_tree(fs_info, path, cur_disk_bytenr,
468 search_len, csum_dst);
469 if (count < 0) {
470 ret = errno_to_blk_status(count);
471 if (bbio)
472 btrfs_bio_free_csum(bbio);
473 break;
474 }
475
476 /*
477 * We didn't find a csum for this range. We need to make sure
478 * we complain loudly about this, because we are not NODATASUM.
479 *
480 * However for the DATA_RELOC inode we could potentially be
481 * relocating data extents for a NODATASUM inode, so the inode
482 * itself won't be marked with NODATASUM, but the extent we're
483 * copying is in fact NODATASUM. If we don't find a csum we
484 * assume this is the case.
485 */
486 if (count == 0) {
487 memset(csum_dst, 0, csum_size);
488 count = 1;
489
490 if (BTRFS_I(inode)->root->root_key.objectid ==
491 BTRFS_DATA_RELOC_TREE_OBJECTID) {
492 u64 file_offset;
493 int ret;
494
495 ret = search_file_offset_in_bio(bio, inode,
496 cur_disk_bytenr, &file_offset);
497 if (ret)
498 set_extent_bits(io_tree, file_offset,
499 file_offset + sectorsize - 1,
500 EXTENT_NODATASUM);
501 } else {
502 btrfs_warn_rl(fs_info,
503 "csum hole found for disk bytenr range [%llu, %llu)",
504 cur_disk_bytenr, cur_disk_bytenr + sectorsize);
505 }
506 }
507 }
508
509 btrfs_free_path(path);
510 return ret;
511 }
512
btrfs_lookup_csums_range(struct btrfs_root * root,u64 start,u64 end,struct list_head * list,int search_commit,bool nowait)513 int btrfs_lookup_csums_range(struct btrfs_root *root, u64 start, u64 end,
514 struct list_head *list, int search_commit,
515 bool nowait)
516 {
517 struct btrfs_fs_info *fs_info = root->fs_info;
518 struct btrfs_key key;
519 struct btrfs_path *path;
520 struct extent_buffer *leaf;
521 struct btrfs_ordered_sum *sums;
522 struct btrfs_csum_item *item;
523 LIST_HEAD(tmplist);
524 unsigned long offset;
525 int ret;
526 size_t size;
527 u64 csum_end;
528 const u32 csum_size = fs_info->csum_size;
529
530 ASSERT(IS_ALIGNED(start, fs_info->sectorsize) &&
531 IS_ALIGNED(end + 1, fs_info->sectorsize));
532
533 path = btrfs_alloc_path();
534 if (!path)
535 return -ENOMEM;
536
537 path->nowait = nowait;
538 if (search_commit) {
539 path->skip_locking = 1;
540 path->reada = READA_FORWARD;
541 path->search_commit_root = 1;
542 }
543
544 key.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
545 key.offset = start;
546 key.type = BTRFS_EXTENT_CSUM_KEY;
547
548 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
549 if (ret < 0)
550 goto fail;
551 if (ret > 0 && path->slots[0] > 0) {
552 leaf = path->nodes[0];
553 btrfs_item_key_to_cpu(leaf, &key, path->slots[0] - 1);
554 if (key.objectid == BTRFS_EXTENT_CSUM_OBJECTID &&
555 key.type == BTRFS_EXTENT_CSUM_KEY) {
556 offset = (start - key.offset) >> fs_info->sectorsize_bits;
557 if (offset * csum_size <
558 btrfs_item_size(leaf, path->slots[0] - 1))
559 path->slots[0]--;
560 }
561 }
562
563 while (start <= end) {
564 leaf = path->nodes[0];
565 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
566 ret = btrfs_next_leaf(root, path);
567 if (ret < 0)
568 goto fail;
569 if (ret > 0)
570 break;
571 leaf = path->nodes[0];
572 }
573
574 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
575 if (key.objectid != BTRFS_EXTENT_CSUM_OBJECTID ||
576 key.type != BTRFS_EXTENT_CSUM_KEY ||
577 key.offset > end)
578 break;
579
580 if (key.offset > start)
581 start = key.offset;
582
583 size = btrfs_item_size(leaf, path->slots[0]);
584 csum_end = key.offset + (size / csum_size) * fs_info->sectorsize;
585 if (csum_end <= start) {
586 path->slots[0]++;
587 continue;
588 }
589
590 csum_end = min(csum_end, end + 1);
591 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
592 struct btrfs_csum_item);
593 while (start < csum_end) {
594 size = min_t(size_t, csum_end - start,
595 max_ordered_sum_bytes(fs_info, csum_size));
596 sums = kzalloc(btrfs_ordered_sum_size(fs_info, size),
597 GFP_NOFS);
598 if (!sums) {
599 ret = -ENOMEM;
600 goto fail;
601 }
602
603 sums->bytenr = start;
604 sums->len = (int)size;
605
606 offset = (start - key.offset) >> fs_info->sectorsize_bits;
607 offset *= csum_size;
608 size >>= fs_info->sectorsize_bits;
609
610 read_extent_buffer(path->nodes[0],
611 sums->sums,
612 ((unsigned long)item) + offset,
613 csum_size * size);
614
615 start += fs_info->sectorsize * size;
616 list_add_tail(&sums->list, &tmplist);
617 }
618 path->slots[0]++;
619 }
620 ret = 0;
621 fail:
622 while (ret < 0 && !list_empty(&tmplist)) {
623 sums = list_entry(tmplist.next, struct btrfs_ordered_sum, list);
624 list_del(&sums->list);
625 kfree(sums);
626 }
627 list_splice_tail(&tmplist, list);
628
629 btrfs_free_path(path);
630 return ret;
631 }
632
633 /**
634 * Calculate checksums of the data contained inside a bio
635 *
636 * @inode: Owner of the data inside the bio
637 * @bio: Contains the data to be checksummed
638 * @offset: If (u64)-1, @bio may contain discontiguous bio vecs, so the
639 * file offsets are determined from the page offsets in the bio.
640 * Otherwise, this is the starting file offset of the bio vecs in
641 * @bio, which must be contiguous.
642 * @one_ordered: If true, @bio only refers to one ordered extent.
643 */
btrfs_csum_one_bio(struct btrfs_inode * inode,struct bio * bio,u64 offset,bool one_ordered)644 blk_status_t btrfs_csum_one_bio(struct btrfs_inode *inode, struct bio *bio,
645 u64 offset, bool one_ordered)
646 {
647 struct btrfs_fs_info *fs_info = inode->root->fs_info;
648 SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
649 struct btrfs_ordered_sum *sums;
650 struct btrfs_ordered_extent *ordered = NULL;
651 const bool use_page_offsets = (offset == (u64)-1);
652 char *data;
653 struct bvec_iter iter;
654 struct bio_vec bvec;
655 int index;
656 unsigned int blockcount;
657 unsigned long total_bytes = 0;
658 unsigned long this_sum_bytes = 0;
659 int i;
660 unsigned nofs_flag;
661
662 nofs_flag = memalloc_nofs_save();
663 sums = kvzalloc(btrfs_ordered_sum_size(fs_info, bio->bi_iter.bi_size),
664 GFP_KERNEL);
665 memalloc_nofs_restore(nofs_flag);
666
667 if (!sums)
668 return BLK_STS_RESOURCE;
669
670 sums->len = bio->bi_iter.bi_size;
671 INIT_LIST_HEAD(&sums->list);
672
673 sums->bytenr = bio->bi_iter.bi_sector << 9;
674 index = 0;
675
676 shash->tfm = fs_info->csum_shash;
677
678 bio_for_each_segment(bvec, bio, iter) {
679 if (use_page_offsets)
680 offset = page_offset(bvec.bv_page) + bvec.bv_offset;
681
682 if (!ordered) {
683 ordered = btrfs_lookup_ordered_extent(inode, offset);
684 /*
685 * The bio range is not covered by any ordered extent,
686 * must be a code logic error.
687 */
688 if (unlikely(!ordered)) {
689 WARN(1, KERN_WARNING
690 "no ordered extent for root %llu ino %llu offset %llu\n",
691 inode->root->root_key.objectid,
692 btrfs_ino(inode), offset);
693 kvfree(sums);
694 return BLK_STS_IOERR;
695 }
696 }
697
698 blockcount = BTRFS_BYTES_TO_BLKS(fs_info,
699 bvec.bv_len + fs_info->sectorsize
700 - 1);
701
702 for (i = 0; i < blockcount; i++) {
703 if (!one_ordered &&
704 !in_range(offset, ordered->file_offset,
705 ordered->num_bytes)) {
706 unsigned long bytes_left;
707
708 sums->len = this_sum_bytes;
709 this_sum_bytes = 0;
710 btrfs_add_ordered_sum(ordered, sums);
711 btrfs_put_ordered_extent(ordered);
712
713 bytes_left = bio->bi_iter.bi_size - total_bytes;
714
715 nofs_flag = memalloc_nofs_save();
716 sums = kvzalloc(btrfs_ordered_sum_size(fs_info,
717 bytes_left), GFP_KERNEL);
718 memalloc_nofs_restore(nofs_flag);
719 BUG_ON(!sums); /* -ENOMEM */
720 sums->len = bytes_left;
721 ordered = btrfs_lookup_ordered_extent(inode,
722 offset);
723 ASSERT(ordered); /* Logic error */
724 sums->bytenr = (bio->bi_iter.bi_sector << 9)
725 + total_bytes;
726 index = 0;
727 }
728
729 data = bvec_kmap_local(&bvec);
730 crypto_shash_digest(shash,
731 data + (i * fs_info->sectorsize),
732 fs_info->sectorsize,
733 sums->sums + index);
734 kunmap_local(data);
735 index += fs_info->csum_size;
736 offset += fs_info->sectorsize;
737 this_sum_bytes += fs_info->sectorsize;
738 total_bytes += fs_info->sectorsize;
739 }
740
741 }
742 this_sum_bytes = 0;
743 btrfs_add_ordered_sum(ordered, sums);
744 btrfs_put_ordered_extent(ordered);
745 return 0;
746 }
747
748 /*
749 * helper function for csum removal, this expects the
750 * key to describe the csum pointed to by the path, and it expects
751 * the csum to overlap the range [bytenr, len]
752 *
753 * The csum should not be entirely contained in the range and the
754 * range should not be entirely contained in the csum.
755 *
756 * This calls btrfs_truncate_item with the correct args based on the
757 * overlap, and fixes up the key as required.
758 */
truncate_one_csum(struct btrfs_fs_info * fs_info,struct btrfs_path * path,struct btrfs_key * key,u64 bytenr,u64 len)759 static noinline void truncate_one_csum(struct btrfs_fs_info *fs_info,
760 struct btrfs_path *path,
761 struct btrfs_key *key,
762 u64 bytenr, u64 len)
763 {
764 struct extent_buffer *leaf;
765 const u32 csum_size = fs_info->csum_size;
766 u64 csum_end;
767 u64 end_byte = bytenr + len;
768 u32 blocksize_bits = fs_info->sectorsize_bits;
769
770 leaf = path->nodes[0];
771 csum_end = btrfs_item_size(leaf, path->slots[0]) / csum_size;
772 csum_end <<= blocksize_bits;
773 csum_end += key->offset;
774
775 if (key->offset < bytenr && csum_end <= end_byte) {
776 /*
777 * [ bytenr - len ]
778 * [ ]
779 * [csum ]
780 * A simple truncate off the end of the item
781 */
782 u32 new_size = (bytenr - key->offset) >> blocksize_bits;
783 new_size *= csum_size;
784 btrfs_truncate_item(path, new_size, 1);
785 } else if (key->offset >= bytenr && csum_end > end_byte &&
786 end_byte > key->offset) {
787 /*
788 * [ bytenr - len ]
789 * [ ]
790 * [csum ]
791 * we need to truncate from the beginning of the csum
792 */
793 u32 new_size = (csum_end - end_byte) >> blocksize_bits;
794 new_size *= csum_size;
795
796 btrfs_truncate_item(path, new_size, 0);
797
798 key->offset = end_byte;
799 btrfs_set_item_key_safe(fs_info, path, key);
800 } else {
801 BUG();
802 }
803 }
804
805 /*
806 * deletes the csum items from the csum tree for a given
807 * range of bytes.
808 */
btrfs_del_csums(struct btrfs_trans_handle * trans,struct btrfs_root * root,u64 bytenr,u64 len)809 int btrfs_del_csums(struct btrfs_trans_handle *trans,
810 struct btrfs_root *root, u64 bytenr, u64 len)
811 {
812 struct btrfs_fs_info *fs_info = trans->fs_info;
813 struct btrfs_path *path;
814 struct btrfs_key key;
815 u64 end_byte = bytenr + len;
816 u64 csum_end;
817 struct extent_buffer *leaf;
818 int ret = 0;
819 const u32 csum_size = fs_info->csum_size;
820 u32 blocksize_bits = fs_info->sectorsize_bits;
821
822 ASSERT(root->root_key.objectid == BTRFS_CSUM_TREE_OBJECTID ||
823 root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID);
824
825 path = btrfs_alloc_path();
826 if (!path)
827 return -ENOMEM;
828
829 while (1) {
830 key.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
831 key.offset = end_byte - 1;
832 key.type = BTRFS_EXTENT_CSUM_KEY;
833
834 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
835 if (ret > 0) {
836 ret = 0;
837 if (path->slots[0] == 0)
838 break;
839 path->slots[0]--;
840 } else if (ret < 0) {
841 break;
842 }
843
844 leaf = path->nodes[0];
845 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
846
847 if (key.objectid != BTRFS_EXTENT_CSUM_OBJECTID ||
848 key.type != BTRFS_EXTENT_CSUM_KEY) {
849 break;
850 }
851
852 if (key.offset >= end_byte)
853 break;
854
855 csum_end = btrfs_item_size(leaf, path->slots[0]) / csum_size;
856 csum_end <<= blocksize_bits;
857 csum_end += key.offset;
858
859 /* this csum ends before we start, we're done */
860 if (csum_end <= bytenr)
861 break;
862
863 /* delete the entire item, it is inside our range */
864 if (key.offset >= bytenr && csum_end <= end_byte) {
865 int del_nr = 1;
866
867 /*
868 * Check how many csum items preceding this one in this
869 * leaf correspond to our range and then delete them all
870 * at once.
871 */
872 if (key.offset > bytenr && path->slots[0] > 0) {
873 int slot = path->slots[0] - 1;
874
875 while (slot >= 0) {
876 struct btrfs_key pk;
877
878 btrfs_item_key_to_cpu(leaf, &pk, slot);
879 if (pk.offset < bytenr ||
880 pk.type != BTRFS_EXTENT_CSUM_KEY ||
881 pk.objectid !=
882 BTRFS_EXTENT_CSUM_OBJECTID)
883 break;
884 path->slots[0] = slot;
885 del_nr++;
886 key.offset = pk.offset;
887 slot--;
888 }
889 }
890 ret = btrfs_del_items(trans, root, path,
891 path->slots[0], del_nr);
892 if (ret)
893 break;
894 if (key.offset == bytenr)
895 break;
896 } else if (key.offset < bytenr && csum_end > end_byte) {
897 unsigned long offset;
898 unsigned long shift_len;
899 unsigned long item_offset;
900 /*
901 * [ bytenr - len ]
902 * [csum ]
903 *
904 * Our bytes are in the middle of the csum,
905 * we need to split this item and insert a new one.
906 *
907 * But we can't drop the path because the
908 * csum could change, get removed, extended etc.
909 *
910 * The trick here is the max size of a csum item leaves
911 * enough room in the tree block for a single
912 * item header. So, we split the item in place,
913 * adding a new header pointing to the existing
914 * bytes. Then we loop around again and we have
915 * a nicely formed csum item that we can neatly
916 * truncate.
917 */
918 offset = (bytenr - key.offset) >> blocksize_bits;
919 offset *= csum_size;
920
921 shift_len = (len >> blocksize_bits) * csum_size;
922
923 item_offset = btrfs_item_ptr_offset(leaf,
924 path->slots[0]);
925
926 memzero_extent_buffer(leaf, item_offset + offset,
927 shift_len);
928 key.offset = bytenr;
929
930 /*
931 * btrfs_split_item returns -EAGAIN when the
932 * item changed size or key
933 */
934 ret = btrfs_split_item(trans, root, path, &key, offset);
935 if (ret && ret != -EAGAIN) {
936 btrfs_abort_transaction(trans, ret);
937 break;
938 }
939 ret = 0;
940
941 key.offset = end_byte - 1;
942 } else {
943 truncate_one_csum(fs_info, path, &key, bytenr, len);
944 if (key.offset < bytenr)
945 break;
946 }
947 btrfs_release_path(path);
948 }
949 btrfs_free_path(path);
950 return ret;
951 }
952
find_next_csum_offset(struct btrfs_root * root,struct btrfs_path * path,u64 * next_offset)953 static int find_next_csum_offset(struct btrfs_root *root,
954 struct btrfs_path *path,
955 u64 *next_offset)
956 {
957 const u32 nritems = btrfs_header_nritems(path->nodes[0]);
958 struct btrfs_key found_key;
959 int slot = path->slots[0] + 1;
960 int ret;
961
962 if (nritems == 0 || slot >= nritems) {
963 ret = btrfs_next_leaf(root, path);
964 if (ret < 0) {
965 return ret;
966 } else if (ret > 0) {
967 *next_offset = (u64)-1;
968 return 0;
969 }
970 slot = path->slots[0];
971 }
972
973 btrfs_item_key_to_cpu(path->nodes[0], &found_key, slot);
974
975 if (found_key.objectid != BTRFS_EXTENT_CSUM_OBJECTID ||
976 found_key.type != BTRFS_EXTENT_CSUM_KEY)
977 *next_offset = (u64)-1;
978 else
979 *next_offset = found_key.offset;
980
981 return 0;
982 }
983
btrfs_csum_file_blocks(struct btrfs_trans_handle * trans,struct btrfs_root * root,struct btrfs_ordered_sum * sums)984 int btrfs_csum_file_blocks(struct btrfs_trans_handle *trans,
985 struct btrfs_root *root,
986 struct btrfs_ordered_sum *sums)
987 {
988 struct btrfs_fs_info *fs_info = root->fs_info;
989 struct btrfs_key file_key;
990 struct btrfs_key found_key;
991 struct btrfs_path *path;
992 struct btrfs_csum_item *item;
993 struct btrfs_csum_item *item_end;
994 struct extent_buffer *leaf = NULL;
995 u64 next_offset;
996 u64 total_bytes = 0;
997 u64 csum_offset;
998 u64 bytenr;
999 u32 ins_size;
1000 int index = 0;
1001 int found_next;
1002 int ret;
1003 const u32 csum_size = fs_info->csum_size;
1004
1005 path = btrfs_alloc_path();
1006 if (!path)
1007 return -ENOMEM;
1008 again:
1009 next_offset = (u64)-1;
1010 found_next = 0;
1011 bytenr = sums->bytenr + total_bytes;
1012 file_key.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
1013 file_key.offset = bytenr;
1014 file_key.type = BTRFS_EXTENT_CSUM_KEY;
1015
1016 item = btrfs_lookup_csum(trans, root, path, bytenr, 1);
1017 if (!IS_ERR(item)) {
1018 ret = 0;
1019 leaf = path->nodes[0];
1020 item_end = btrfs_item_ptr(leaf, path->slots[0],
1021 struct btrfs_csum_item);
1022 item_end = (struct btrfs_csum_item *)((char *)item_end +
1023 btrfs_item_size(leaf, path->slots[0]));
1024 goto found;
1025 }
1026 ret = PTR_ERR(item);
1027 if (ret != -EFBIG && ret != -ENOENT)
1028 goto out;
1029
1030 if (ret == -EFBIG) {
1031 u32 item_size;
1032 /* we found one, but it isn't big enough yet */
1033 leaf = path->nodes[0];
1034 item_size = btrfs_item_size(leaf, path->slots[0]);
1035 if ((item_size / csum_size) >=
1036 MAX_CSUM_ITEMS(fs_info, csum_size)) {
1037 /* already at max size, make a new one */
1038 goto insert;
1039 }
1040 } else {
1041 /* We didn't find a csum item, insert one. */
1042 ret = find_next_csum_offset(root, path, &next_offset);
1043 if (ret < 0)
1044 goto out;
1045 found_next = 1;
1046 goto insert;
1047 }
1048
1049 /*
1050 * At this point, we know the tree has a checksum item that ends at an
1051 * offset matching the start of the checksum range we want to insert.
1052 * We try to extend that item as much as possible and then add as many
1053 * checksums to it as they fit.
1054 *
1055 * First check if the leaf has enough free space for at least one
1056 * checksum. If it has go directly to the item extension code, otherwise
1057 * release the path and do a search for insertion before the extension.
1058 */
1059 if (btrfs_leaf_free_space(leaf) >= csum_size) {
1060 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1061 csum_offset = (bytenr - found_key.offset) >>
1062 fs_info->sectorsize_bits;
1063 goto extend_csum;
1064 }
1065
1066 btrfs_release_path(path);
1067 path->search_for_extension = 1;
1068 ret = btrfs_search_slot(trans, root, &file_key, path,
1069 csum_size, 1);
1070 path->search_for_extension = 0;
1071 if (ret < 0)
1072 goto out;
1073
1074 if (ret > 0) {
1075 if (path->slots[0] == 0)
1076 goto insert;
1077 path->slots[0]--;
1078 }
1079
1080 leaf = path->nodes[0];
1081 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1082 csum_offset = (bytenr - found_key.offset) >> fs_info->sectorsize_bits;
1083
1084 if (found_key.type != BTRFS_EXTENT_CSUM_KEY ||
1085 found_key.objectid != BTRFS_EXTENT_CSUM_OBJECTID ||
1086 csum_offset >= MAX_CSUM_ITEMS(fs_info, csum_size)) {
1087 goto insert;
1088 }
1089
1090 extend_csum:
1091 if (csum_offset == btrfs_item_size(leaf, path->slots[0]) /
1092 csum_size) {
1093 int extend_nr;
1094 u64 tmp;
1095 u32 diff;
1096
1097 tmp = sums->len - total_bytes;
1098 tmp >>= fs_info->sectorsize_bits;
1099 WARN_ON(tmp < 1);
1100 extend_nr = max_t(int, 1, tmp);
1101
1102 /*
1103 * A log tree can already have checksum items with a subset of
1104 * the checksums we are trying to log. This can happen after
1105 * doing a sequence of partial writes into prealloc extents and
1106 * fsyncs in between, with a full fsync logging a larger subrange
1107 * of an extent for which a previous fast fsync logged a smaller
1108 * subrange. And this happens in particular due to merging file
1109 * extent items when we complete an ordered extent for a range
1110 * covered by a prealloc extent - this is done at
1111 * btrfs_mark_extent_written().
1112 *
1113 * So if we try to extend the previous checksum item, which has
1114 * a range that ends at the start of the range we want to insert,
1115 * make sure we don't extend beyond the start offset of the next
1116 * checksum item. If we are at the last item in the leaf, then
1117 * forget the optimization of extending and add a new checksum
1118 * item - it is not worth the complexity of releasing the path,
1119 * getting the first key for the next leaf, repeat the btree
1120 * search, etc, because log trees are temporary anyway and it
1121 * would only save a few bytes of leaf space.
1122 */
1123 if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) {
1124 if (path->slots[0] + 1 >=
1125 btrfs_header_nritems(path->nodes[0])) {
1126 ret = find_next_csum_offset(root, path, &next_offset);
1127 if (ret < 0)
1128 goto out;
1129 found_next = 1;
1130 goto insert;
1131 }
1132
1133 ret = find_next_csum_offset(root, path, &next_offset);
1134 if (ret < 0)
1135 goto out;
1136
1137 tmp = (next_offset - bytenr) >> fs_info->sectorsize_bits;
1138 if (tmp <= INT_MAX)
1139 extend_nr = min_t(int, extend_nr, tmp);
1140 }
1141
1142 diff = (csum_offset + extend_nr) * csum_size;
1143 diff = min(diff,
1144 MAX_CSUM_ITEMS(fs_info, csum_size) * csum_size);
1145
1146 diff = diff - btrfs_item_size(leaf, path->slots[0]);
1147 diff = min_t(u32, btrfs_leaf_free_space(leaf), diff);
1148 diff /= csum_size;
1149 diff *= csum_size;
1150
1151 btrfs_extend_item(path, diff);
1152 ret = 0;
1153 goto csum;
1154 }
1155
1156 insert:
1157 btrfs_release_path(path);
1158 csum_offset = 0;
1159 if (found_next) {
1160 u64 tmp;
1161
1162 tmp = sums->len - total_bytes;
1163 tmp >>= fs_info->sectorsize_bits;
1164 tmp = min(tmp, (next_offset - file_key.offset) >>
1165 fs_info->sectorsize_bits);
1166
1167 tmp = max_t(u64, 1, tmp);
1168 tmp = min_t(u64, tmp, MAX_CSUM_ITEMS(fs_info, csum_size));
1169 ins_size = csum_size * tmp;
1170 } else {
1171 ins_size = csum_size;
1172 }
1173 ret = btrfs_insert_empty_item(trans, root, path, &file_key,
1174 ins_size);
1175 if (ret < 0)
1176 goto out;
1177 if (WARN_ON(ret != 0))
1178 goto out;
1179 leaf = path->nodes[0];
1180 csum:
1181 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_csum_item);
1182 item_end = (struct btrfs_csum_item *)((unsigned char *)item +
1183 btrfs_item_size(leaf, path->slots[0]));
1184 item = (struct btrfs_csum_item *)((unsigned char *)item +
1185 csum_offset * csum_size);
1186 found:
1187 ins_size = (u32)(sums->len - total_bytes) >> fs_info->sectorsize_bits;
1188 ins_size *= csum_size;
1189 ins_size = min_t(u32, (unsigned long)item_end - (unsigned long)item,
1190 ins_size);
1191 write_extent_buffer(leaf, sums->sums + index, (unsigned long)item,
1192 ins_size);
1193
1194 index += ins_size;
1195 ins_size /= csum_size;
1196 total_bytes += ins_size * fs_info->sectorsize;
1197
1198 btrfs_mark_buffer_dirty(path->nodes[0]);
1199 if (total_bytes < sums->len) {
1200 btrfs_release_path(path);
1201 cond_resched();
1202 goto again;
1203 }
1204 out:
1205 btrfs_free_path(path);
1206 return ret;
1207 }
1208
btrfs_extent_item_to_extent_map(struct btrfs_inode * inode,const struct btrfs_path * path,struct btrfs_file_extent_item * fi,const bool new_inline,struct extent_map * em)1209 void btrfs_extent_item_to_extent_map(struct btrfs_inode *inode,
1210 const struct btrfs_path *path,
1211 struct btrfs_file_extent_item *fi,
1212 const bool new_inline,
1213 struct extent_map *em)
1214 {
1215 struct btrfs_fs_info *fs_info = inode->root->fs_info;
1216 struct btrfs_root *root = inode->root;
1217 struct extent_buffer *leaf = path->nodes[0];
1218 const int slot = path->slots[0];
1219 struct btrfs_key key;
1220 u64 extent_start, extent_end;
1221 u64 bytenr;
1222 u8 type = btrfs_file_extent_type(leaf, fi);
1223 int compress_type = btrfs_file_extent_compression(leaf, fi);
1224
1225 btrfs_item_key_to_cpu(leaf, &key, slot);
1226 extent_start = key.offset;
1227 extent_end = btrfs_file_extent_end(path);
1228 em->ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi);
1229 em->generation = btrfs_file_extent_generation(leaf, fi);
1230 if (type == BTRFS_FILE_EXTENT_REG ||
1231 type == BTRFS_FILE_EXTENT_PREALLOC) {
1232 em->start = extent_start;
1233 em->len = extent_end - extent_start;
1234 em->orig_start = extent_start -
1235 btrfs_file_extent_offset(leaf, fi);
1236 em->orig_block_len = btrfs_file_extent_disk_num_bytes(leaf, fi);
1237 bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
1238 if (bytenr == 0) {
1239 em->block_start = EXTENT_MAP_HOLE;
1240 return;
1241 }
1242 if (compress_type != BTRFS_COMPRESS_NONE) {
1243 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
1244 em->compress_type = compress_type;
1245 em->block_start = bytenr;
1246 em->block_len = em->orig_block_len;
1247 } else {
1248 bytenr += btrfs_file_extent_offset(leaf, fi);
1249 em->block_start = bytenr;
1250 em->block_len = em->len;
1251 if (type == BTRFS_FILE_EXTENT_PREALLOC)
1252 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
1253 }
1254 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
1255 em->block_start = EXTENT_MAP_INLINE;
1256 em->start = extent_start;
1257 em->len = extent_end - extent_start;
1258 /*
1259 * Initialize orig_start and block_len with the same values
1260 * as in inode.c:btrfs_get_extent().
1261 */
1262 em->orig_start = EXTENT_MAP_HOLE;
1263 em->block_len = (u64)-1;
1264 if (!new_inline && compress_type != BTRFS_COMPRESS_NONE) {
1265 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
1266 em->compress_type = compress_type;
1267 }
1268 } else {
1269 btrfs_err(fs_info,
1270 "unknown file extent item type %d, inode %llu, offset %llu, "
1271 "root %llu", type, btrfs_ino(inode), extent_start,
1272 root->root_key.objectid);
1273 }
1274 }
1275
1276 /*
1277 * Returns the end offset (non inclusive) of the file extent item the given path
1278 * points to. If it points to an inline extent, the returned offset is rounded
1279 * up to the sector size.
1280 */
btrfs_file_extent_end(const struct btrfs_path * path)1281 u64 btrfs_file_extent_end(const struct btrfs_path *path)
1282 {
1283 const struct extent_buffer *leaf = path->nodes[0];
1284 const int slot = path->slots[0];
1285 struct btrfs_file_extent_item *fi;
1286 struct btrfs_key key;
1287 u64 end;
1288
1289 btrfs_item_key_to_cpu(leaf, &key, slot);
1290 ASSERT(key.type == BTRFS_EXTENT_DATA_KEY);
1291 fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
1292
1293 if (btrfs_file_extent_type(leaf, fi) == BTRFS_FILE_EXTENT_INLINE) {
1294 end = btrfs_file_extent_ram_bytes(leaf, fi);
1295 end = ALIGN(key.offset + end, leaf->fs_info->sectorsize);
1296 } else {
1297 end = key.offset + btrfs_file_extent_num_bytes(leaf, fi);
1298 }
1299
1300 return end;
1301 }
1302