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 spin_lock(&inode->lock);
51 i_size = new_i_size ?: i_size_read(&inode->vfs_inode);
52 if (btrfs_fs_incompat(fs_info, NO_HOLES)) {
53 inode->disk_i_size = i_size;
54 goto out_unlock;
55 }
56
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 out_unlock:
65 spin_unlock(&inode->lock);
66 }
67
68 /**
69 * Mark range within a file as having a new extent inserted
70 *
71 * @inode: inode being modified
72 * @start: start file offset of the file extent we've inserted
73 * @len: logical length of the file extent item
74 *
75 * Call when we are inserting a new file extent where there was none before.
76 * Does not need to call this in the case where we're replacing an existing file
77 * extent, however if not sure it's fine to call this multiple times.
78 *
79 * The start and len must match the file extent item, so thus must be sectorsize
80 * aligned.
81 */
btrfs_inode_set_file_extent_range(struct btrfs_inode * inode,u64 start,u64 len)82 int btrfs_inode_set_file_extent_range(struct btrfs_inode *inode, u64 start,
83 u64 len)
84 {
85 if (len == 0)
86 return 0;
87
88 ASSERT(IS_ALIGNED(start + len, inode->root->fs_info->sectorsize));
89
90 if (btrfs_fs_incompat(inode->root->fs_info, NO_HOLES))
91 return 0;
92 return set_extent_bits(&inode->file_extent_tree, start, start + len - 1,
93 EXTENT_DIRTY);
94 }
95
96 /**
97 * Marks an inode range as not having a backing extent
98 *
99 * @inode: inode being modified
100 * @start: start file offset of the file extent we've inserted
101 * @len: logical length of the file extent item
102 *
103 * Called when we drop a file extent, for example when we truncate. Doesn't
104 * need to be called for cases where we're replacing a file extent, like when
105 * we've COWed a file extent.
106 *
107 * The start and len must match the file extent item, so thus must be sectorsize
108 * aligned.
109 */
btrfs_inode_clear_file_extent_range(struct btrfs_inode * inode,u64 start,u64 len)110 int btrfs_inode_clear_file_extent_range(struct btrfs_inode *inode, u64 start,
111 u64 len)
112 {
113 if (len == 0)
114 return 0;
115
116 ASSERT(IS_ALIGNED(start + len, inode->root->fs_info->sectorsize) ||
117 len == (u64)-1);
118
119 if (btrfs_fs_incompat(inode->root->fs_info, NO_HOLES))
120 return 0;
121 return clear_extent_bit(&inode->file_extent_tree, start,
122 start + len - 1, EXTENT_DIRTY, NULL);
123 }
124
max_ordered_sum_bytes(struct btrfs_fs_info * fs_info,u16 csum_size)125 static inline u32 max_ordered_sum_bytes(struct btrfs_fs_info *fs_info,
126 u16 csum_size)
127 {
128 u32 ncsums = (PAGE_SIZE - sizeof(struct btrfs_ordered_sum)) / csum_size;
129
130 return ncsums * fs_info->sectorsize;
131 }
132
133 /*
134 * Calculate the total size needed to allocate for an ordered sum structure
135 * spanning @bytes in the file.
136 */
btrfs_ordered_sum_size(struct btrfs_fs_info * fs_info,unsigned long bytes)137 static int btrfs_ordered_sum_size(struct btrfs_fs_info *fs_info, unsigned long bytes)
138 {
139 int num_sectors = (int)DIV_ROUND_UP(bytes, fs_info->sectorsize);
140
141 return sizeof(struct btrfs_ordered_sum) + num_sectors * fs_info->csum_size;
142 }
143
btrfs_insert_hole_extent(struct btrfs_trans_handle * trans,struct btrfs_root * root,u64 objectid,u64 pos,u64 num_bytes)144 int btrfs_insert_hole_extent(struct btrfs_trans_handle *trans,
145 struct btrfs_root *root,
146 u64 objectid, u64 pos, u64 num_bytes)
147 {
148 int ret = 0;
149 struct btrfs_file_extent_item *item;
150 struct btrfs_key file_key;
151 struct btrfs_path *path;
152 struct extent_buffer *leaf;
153
154 path = btrfs_alloc_path();
155 if (!path)
156 return -ENOMEM;
157 file_key.objectid = objectid;
158 file_key.offset = pos;
159 file_key.type = BTRFS_EXTENT_DATA_KEY;
160
161 ret = btrfs_insert_empty_item(trans, root, path, &file_key,
162 sizeof(*item));
163 if (ret < 0)
164 goto out;
165 BUG_ON(ret); /* Can't happen */
166 leaf = path->nodes[0];
167 item = btrfs_item_ptr(leaf, path->slots[0],
168 struct btrfs_file_extent_item);
169 btrfs_set_file_extent_disk_bytenr(leaf, item, 0);
170 btrfs_set_file_extent_disk_num_bytes(leaf, item, 0);
171 btrfs_set_file_extent_offset(leaf, item, 0);
172 btrfs_set_file_extent_num_bytes(leaf, item, num_bytes);
173 btrfs_set_file_extent_ram_bytes(leaf, item, num_bytes);
174 btrfs_set_file_extent_generation(leaf, item, trans->transid);
175 btrfs_set_file_extent_type(leaf, item, BTRFS_FILE_EXTENT_REG);
176 btrfs_set_file_extent_compression(leaf, item, 0);
177 btrfs_set_file_extent_encryption(leaf, item, 0);
178 btrfs_set_file_extent_other_encoding(leaf, item, 0);
179
180 btrfs_mark_buffer_dirty(leaf);
181 out:
182 btrfs_free_path(path);
183 return ret;
184 }
185
186 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)187 btrfs_lookup_csum(struct btrfs_trans_handle *trans,
188 struct btrfs_root *root,
189 struct btrfs_path *path,
190 u64 bytenr, int cow)
191 {
192 struct btrfs_fs_info *fs_info = root->fs_info;
193 int ret;
194 struct btrfs_key file_key;
195 struct btrfs_key found_key;
196 struct btrfs_csum_item *item;
197 struct extent_buffer *leaf;
198 u64 csum_offset = 0;
199 const u32 csum_size = fs_info->csum_size;
200 int csums_in_item;
201
202 file_key.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
203 file_key.offset = bytenr;
204 file_key.type = BTRFS_EXTENT_CSUM_KEY;
205 ret = btrfs_search_slot(trans, root, &file_key, path, 0, cow);
206 if (ret < 0)
207 goto fail;
208 leaf = path->nodes[0];
209 if (ret > 0) {
210 ret = 1;
211 if (path->slots[0] == 0)
212 goto fail;
213 path->slots[0]--;
214 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
215 if (found_key.type != BTRFS_EXTENT_CSUM_KEY)
216 goto fail;
217
218 csum_offset = (bytenr - found_key.offset) >>
219 fs_info->sectorsize_bits;
220 csums_in_item = btrfs_item_size(leaf, path->slots[0]);
221 csums_in_item /= csum_size;
222
223 if (csum_offset == csums_in_item) {
224 ret = -EFBIG;
225 goto fail;
226 } else if (csum_offset > csums_in_item) {
227 goto fail;
228 }
229 }
230 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_csum_item);
231 item = (struct btrfs_csum_item *)((unsigned char *)item +
232 csum_offset * csum_size);
233 return item;
234 fail:
235 if (ret > 0)
236 ret = -ENOENT;
237 return ERR_PTR(ret);
238 }
239
btrfs_lookup_file_extent(struct btrfs_trans_handle * trans,struct btrfs_root * root,struct btrfs_path * path,u64 objectid,u64 offset,int mod)240 int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans,
241 struct btrfs_root *root,
242 struct btrfs_path *path, u64 objectid,
243 u64 offset, int mod)
244 {
245 struct btrfs_key file_key;
246 int ins_len = mod < 0 ? -1 : 0;
247 int cow = mod != 0;
248
249 file_key.objectid = objectid;
250 file_key.offset = offset;
251 file_key.type = BTRFS_EXTENT_DATA_KEY;
252
253 return btrfs_search_slot(trans, root, &file_key, path, ins_len, cow);
254 }
255
256 /*
257 * Find checksums for logical bytenr range [disk_bytenr, disk_bytenr + len) and
258 * estore the result to @dst.
259 *
260 * Return >0 for the number of sectors we found.
261 * Return 0 for the range [disk_bytenr, disk_bytenr + sectorsize) has no csum
262 * for it. Caller may want to try next sector until one range is hit.
263 * Return <0 for fatal error.
264 */
search_csum_tree(struct btrfs_fs_info * fs_info,struct btrfs_path * path,u64 disk_bytenr,u64 len,u8 * dst)265 static int search_csum_tree(struct btrfs_fs_info *fs_info,
266 struct btrfs_path *path, u64 disk_bytenr,
267 u64 len, u8 *dst)
268 {
269 struct btrfs_root *csum_root;
270 struct btrfs_csum_item *item = NULL;
271 struct btrfs_key key;
272 const u32 sectorsize = fs_info->sectorsize;
273 const u32 csum_size = fs_info->csum_size;
274 u32 itemsize;
275 int ret;
276 u64 csum_start;
277 u64 csum_len;
278
279 ASSERT(IS_ALIGNED(disk_bytenr, sectorsize) &&
280 IS_ALIGNED(len, sectorsize));
281
282 /* Check if the current csum item covers disk_bytenr */
283 if (path->nodes[0]) {
284 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
285 struct btrfs_csum_item);
286 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
287 itemsize = btrfs_item_size(path->nodes[0], path->slots[0]);
288
289 csum_start = key.offset;
290 csum_len = (itemsize / csum_size) * sectorsize;
291
292 if (in_range(disk_bytenr, csum_start, csum_len))
293 goto found;
294 }
295
296 /* Current item doesn't contain the desired range, search again */
297 btrfs_release_path(path);
298 csum_root = btrfs_csum_root(fs_info, disk_bytenr);
299 item = btrfs_lookup_csum(NULL, csum_root, path, disk_bytenr, 0);
300 if (IS_ERR(item)) {
301 ret = PTR_ERR(item);
302 goto out;
303 }
304 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
305 itemsize = btrfs_item_size(path->nodes[0], path->slots[0]);
306
307 csum_start = key.offset;
308 csum_len = (itemsize / csum_size) * sectorsize;
309 ASSERT(in_range(disk_bytenr, csum_start, csum_len));
310
311 found:
312 ret = (min(csum_start + csum_len, disk_bytenr + len) -
313 disk_bytenr) >> fs_info->sectorsize_bits;
314 read_extent_buffer(path->nodes[0], dst, (unsigned long)item,
315 ret * csum_size);
316 out:
317 if (ret == -ENOENT || ret == -EFBIG)
318 ret = 0;
319 return ret;
320 }
321
322 /*
323 * Locate the file_offset of @cur_disk_bytenr of a @bio.
324 *
325 * Bio of btrfs represents read range of
326 * [bi_sector << 9, bi_sector << 9 + bi_size).
327 * Knowing this, we can iterate through each bvec to locate the page belong to
328 * @cur_disk_bytenr and get the file offset.
329 *
330 * @inode is used to determine if the bvec page really belongs to @inode.
331 *
332 * Return 0 if we can't find the file offset
333 * Return >0 if we find the file offset and restore it to @file_offset_ret
334 */
search_file_offset_in_bio(struct bio * bio,struct inode * inode,u64 disk_bytenr,u64 * file_offset_ret)335 static int search_file_offset_in_bio(struct bio *bio, struct inode *inode,
336 u64 disk_bytenr, u64 *file_offset_ret)
337 {
338 struct bvec_iter iter;
339 struct bio_vec bvec;
340 u64 cur = bio->bi_iter.bi_sector << SECTOR_SHIFT;
341 int ret = 0;
342
343 bio_for_each_segment(bvec, bio, iter) {
344 struct page *page = bvec.bv_page;
345
346 if (cur > disk_bytenr)
347 break;
348 if (cur + bvec.bv_len <= disk_bytenr) {
349 cur += bvec.bv_len;
350 continue;
351 }
352 ASSERT(in_range(disk_bytenr, cur, bvec.bv_len));
353 if (page->mapping && page->mapping->host &&
354 page->mapping->host == inode) {
355 ret = 1;
356 *file_offset_ret = page_offset(page) + bvec.bv_offset +
357 disk_bytenr - cur;
358 break;
359 }
360 }
361 return ret;
362 }
363
364 /**
365 * Lookup the checksum for the read bio in csum tree.
366 *
367 * @inode: inode that the bio is for.
368 * @bio: bio to look up.
369 * @dst: Buffer of size nblocks * btrfs_super_csum_size() used to return
370 * checksum (nblocks = bio->bi_iter.bi_size / fs_info->sectorsize). If
371 * NULL, the checksum buffer is allocated and returned in
372 * btrfs_bio(bio)->csum instead.
373 *
374 * Return: BLK_STS_RESOURCE if allocating memory fails, BLK_STS_OK otherwise.
375 */
btrfs_lookup_bio_sums(struct inode * inode,struct bio * bio,u8 * dst)376 blk_status_t btrfs_lookup_bio_sums(struct inode *inode, struct bio *bio, u8 *dst)
377 {
378 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
379 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
380 struct btrfs_bio *bbio = NULL;
381 struct btrfs_path *path;
382 const u32 sectorsize = fs_info->sectorsize;
383 const u32 csum_size = fs_info->csum_size;
384 u32 orig_len = bio->bi_iter.bi_size;
385 u64 orig_disk_bytenr = bio->bi_iter.bi_sector << SECTOR_SHIFT;
386 u64 cur_disk_bytenr;
387 u8 *csum;
388 const unsigned int nblocks = orig_len >> fs_info->sectorsize_bits;
389 int count = 0;
390 blk_status_t ret = BLK_STS_OK;
391
392 if ((BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM) ||
393 test_bit(BTRFS_FS_STATE_NO_CSUMS, &fs_info->fs_state))
394 return BLK_STS_OK;
395
396 /*
397 * This function is only called for read bio.
398 *
399 * This means two things:
400 * - All our csums should only be in csum tree
401 * No ordered extents csums, as ordered extents are only for write
402 * path.
403 * - No need to bother any other info from bvec
404 * Since we're looking up csums, the only important info is the
405 * disk_bytenr and the length, which can be extracted from bi_iter
406 * directly.
407 */
408 ASSERT(bio_op(bio) == REQ_OP_READ);
409 path = btrfs_alloc_path();
410 if (!path)
411 return BLK_STS_RESOURCE;
412
413 if (!dst) {
414 bbio = btrfs_bio(bio);
415
416 if (nblocks * csum_size > BTRFS_BIO_INLINE_CSUM_SIZE) {
417 bbio->csum = kmalloc_array(nblocks, csum_size, GFP_NOFS);
418 if (!bbio->csum) {
419 btrfs_free_path(path);
420 return BLK_STS_RESOURCE;
421 }
422 } else {
423 bbio->csum = bbio->csum_inline;
424 }
425 csum = bbio->csum;
426 } else {
427 csum = dst;
428 }
429
430 /*
431 * If requested number of sectors is larger than one leaf can contain,
432 * kick the readahead for csum tree.
433 */
434 if (nblocks > fs_info->csums_per_leaf)
435 path->reada = READA_FORWARD;
436
437 /*
438 * the free space stuff is only read when it hasn't been
439 * updated in the current transaction. So, we can safely
440 * read from the commit root and sidestep a nasty deadlock
441 * between reading the free space cache and updating the csum tree.
442 */
443 if (btrfs_is_free_space_inode(BTRFS_I(inode))) {
444 path->search_commit_root = 1;
445 path->skip_locking = 1;
446 }
447
448 for (cur_disk_bytenr = orig_disk_bytenr;
449 cur_disk_bytenr < orig_disk_bytenr + orig_len;
450 cur_disk_bytenr += (count * sectorsize)) {
451 u64 search_len = orig_disk_bytenr + orig_len - cur_disk_bytenr;
452 unsigned int sector_offset;
453 u8 *csum_dst;
454
455 /*
456 * Although both cur_disk_bytenr and orig_disk_bytenr is u64,
457 * we're calculating the offset to the bio start.
458 *
459 * Bio size is limited to UINT_MAX, thus unsigned int is large
460 * enough to contain the raw result, not to mention the right
461 * shifted result.
462 */
463 ASSERT(cur_disk_bytenr - orig_disk_bytenr < UINT_MAX);
464 sector_offset = (cur_disk_bytenr - orig_disk_bytenr) >>
465 fs_info->sectorsize_bits;
466 csum_dst = csum + sector_offset * csum_size;
467
468 count = search_csum_tree(fs_info, path, cur_disk_bytenr,
469 search_len, csum_dst);
470 if (count < 0) {
471 ret = errno_to_blk_status(count);
472 if (bbio)
473 btrfs_bio_free_csum(bbio);
474 break;
475 }
476
477 /*
478 * We didn't find a csum for this range. We need to make sure
479 * we complain loudly about this, because we are not NODATASUM.
480 *
481 * However for the DATA_RELOC inode we could potentially be
482 * relocating data extents for a NODATASUM inode, so the inode
483 * itself won't be marked with NODATASUM, but the extent we're
484 * copying is in fact NODATASUM. If we don't find a csum we
485 * assume this is the case.
486 */
487 if (count == 0) {
488 memset(csum_dst, 0, csum_size);
489 count = 1;
490
491 if (BTRFS_I(inode)->root->root_key.objectid ==
492 BTRFS_DATA_RELOC_TREE_OBJECTID) {
493 u64 file_offset;
494 int ret;
495
496 ret = search_file_offset_in_bio(bio, inode,
497 cur_disk_bytenr, &file_offset);
498 if (ret)
499 set_extent_bits(io_tree, file_offset,
500 file_offset + sectorsize - 1,
501 EXTENT_NODATASUM);
502 } else {
503 btrfs_warn_rl(fs_info,
504 "csum hole found for disk bytenr range [%llu, %llu)",
505 cur_disk_bytenr, cur_disk_bytenr + sectorsize);
506 }
507 }
508 }
509
510 btrfs_free_path(path);
511 return ret;
512 }
513
btrfs_lookup_csums_range(struct btrfs_root * root,u64 start,u64 end,struct list_head * list,int search_commit,bool nowait)514 int btrfs_lookup_csums_range(struct btrfs_root *root, u64 start, u64 end,
515 struct list_head *list, int search_commit,
516 bool nowait)
517 {
518 struct btrfs_fs_info *fs_info = root->fs_info;
519 struct btrfs_key key;
520 struct btrfs_path *path;
521 struct extent_buffer *leaf;
522 struct btrfs_ordered_sum *sums;
523 struct btrfs_csum_item *item;
524 LIST_HEAD(tmplist);
525 unsigned long offset;
526 int ret;
527 size_t size;
528 u64 csum_end;
529 const u32 csum_size = fs_info->csum_size;
530
531 ASSERT(IS_ALIGNED(start, fs_info->sectorsize) &&
532 IS_ALIGNED(end + 1, fs_info->sectorsize));
533
534 path = btrfs_alloc_path();
535 if (!path)
536 return -ENOMEM;
537
538 path->nowait = nowait;
539 if (search_commit) {
540 path->skip_locking = 1;
541 path->reada = READA_FORWARD;
542 path->search_commit_root = 1;
543 }
544
545 key.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
546 key.offset = start;
547 key.type = BTRFS_EXTENT_CSUM_KEY;
548
549 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
550 if (ret < 0)
551 goto fail;
552 if (ret > 0 && path->slots[0] > 0) {
553 leaf = path->nodes[0];
554 btrfs_item_key_to_cpu(leaf, &key, path->slots[0] - 1);
555 if (key.objectid == BTRFS_EXTENT_CSUM_OBJECTID &&
556 key.type == BTRFS_EXTENT_CSUM_KEY) {
557 offset = (start - key.offset) >> fs_info->sectorsize_bits;
558 if (offset * csum_size <
559 btrfs_item_size(leaf, path->slots[0] - 1))
560 path->slots[0]--;
561 }
562 }
563
564 while (start <= end) {
565 leaf = path->nodes[0];
566 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
567 ret = btrfs_next_leaf(root, path);
568 if (ret < 0)
569 goto fail;
570 if (ret > 0)
571 break;
572 leaf = path->nodes[0];
573 }
574
575 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
576 if (key.objectid != BTRFS_EXTENT_CSUM_OBJECTID ||
577 key.type != BTRFS_EXTENT_CSUM_KEY ||
578 key.offset > end)
579 break;
580
581 if (key.offset > start)
582 start = key.offset;
583
584 size = btrfs_item_size(leaf, path->slots[0]);
585 csum_end = key.offset + (size / csum_size) * fs_info->sectorsize;
586 if (csum_end <= start) {
587 path->slots[0]++;
588 continue;
589 }
590
591 csum_end = min(csum_end, end + 1);
592 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
593 struct btrfs_csum_item);
594 while (start < csum_end) {
595 size = min_t(size_t, csum_end - start,
596 max_ordered_sum_bytes(fs_info, csum_size));
597 sums = kzalloc(btrfs_ordered_sum_size(fs_info, size),
598 GFP_NOFS);
599 if (!sums) {
600 ret = -ENOMEM;
601 goto fail;
602 }
603
604 sums->bytenr = start;
605 sums->len = size;
606
607 offset = (start - key.offset) >> fs_info->sectorsize_bits;
608 offset *= csum_size;
609 size >>= fs_info->sectorsize_bits;
610
611 read_extent_buffer(path->nodes[0],
612 sums->sums,
613 ((unsigned long)item) + offset,
614 csum_size * size);
615
616 start += fs_info->sectorsize * size;
617 list_add_tail(&sums->list, &tmplist);
618 }
619 path->slots[0]++;
620 }
621 ret = 0;
622 fail:
623 while (ret < 0 && !list_empty(&tmplist)) {
624 sums = list_entry(tmplist.next, struct btrfs_ordered_sum, list);
625 list_del(&sums->list);
626 kfree(sums);
627 }
628 list_splice_tail(&tmplist, list);
629
630 btrfs_free_path(path);
631 return ret;
632 }
633
634 /**
635 * Calculate checksums of the data contained inside a bio
636 *
637 * @inode: Owner of the data inside the bio
638 * @bio: Contains the data to be checksummed
639 * @offset: If (u64)-1, @bio may contain discontiguous bio vecs, so the
640 * file offsets are determined from the page offsets in the bio.
641 * Otherwise, this is the starting file offset of the bio vecs in
642 * @bio, which must be contiguous.
643 * @one_ordered: If true, @bio only refers to one ordered extent.
644 */
btrfs_csum_one_bio(struct btrfs_inode * inode,struct bio * bio,u64 offset,bool one_ordered)645 blk_status_t btrfs_csum_one_bio(struct btrfs_inode *inode, struct bio *bio,
646 u64 offset, bool one_ordered)
647 {
648 struct btrfs_fs_info *fs_info = inode->root->fs_info;
649 SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
650 struct btrfs_ordered_sum *sums;
651 struct btrfs_ordered_extent *ordered = NULL;
652 const bool use_page_offsets = (offset == (u64)-1);
653 char *data;
654 struct bvec_iter iter;
655 struct bio_vec bvec;
656 int index;
657 unsigned int blockcount;
658 unsigned long total_bytes = 0;
659 unsigned long this_sum_bytes = 0;
660 int i;
661 unsigned nofs_flag;
662
663 nofs_flag = memalloc_nofs_save();
664 sums = kvzalloc(btrfs_ordered_sum_size(fs_info, bio->bi_iter.bi_size),
665 GFP_KERNEL);
666 memalloc_nofs_restore(nofs_flag);
667
668 if (!sums)
669 return BLK_STS_RESOURCE;
670
671 sums->len = bio->bi_iter.bi_size;
672 INIT_LIST_HEAD(&sums->list);
673
674 sums->bytenr = bio->bi_iter.bi_sector << 9;
675 index = 0;
676
677 shash->tfm = fs_info->csum_shash;
678
679 bio_for_each_segment(bvec, bio, iter) {
680 if (use_page_offsets)
681 offset = page_offset(bvec.bv_page) + bvec.bv_offset;
682
683 if (!ordered) {
684 ordered = btrfs_lookup_ordered_extent(inode, offset);
685 /*
686 * The bio range is not covered by any ordered extent,
687 * must be a code logic error.
688 */
689 if (unlikely(!ordered)) {
690 WARN(1, KERN_WARNING
691 "no ordered extent for root %llu ino %llu offset %llu\n",
692 inode->root->root_key.objectid,
693 btrfs_ino(inode), offset);
694 kvfree(sums);
695 return BLK_STS_IOERR;
696 }
697 }
698
699 blockcount = BTRFS_BYTES_TO_BLKS(fs_info,
700 bvec.bv_len + fs_info->sectorsize
701 - 1);
702
703 for (i = 0; i < blockcount; i++) {
704 if (!one_ordered &&
705 !in_range(offset, ordered->file_offset,
706 ordered->num_bytes)) {
707 unsigned long bytes_left;
708
709 sums->len = this_sum_bytes;
710 this_sum_bytes = 0;
711 btrfs_add_ordered_sum(ordered, sums);
712 btrfs_put_ordered_extent(ordered);
713
714 bytes_left = bio->bi_iter.bi_size - total_bytes;
715
716 nofs_flag = memalloc_nofs_save();
717 sums = kvzalloc(btrfs_ordered_sum_size(fs_info,
718 bytes_left), GFP_KERNEL);
719 memalloc_nofs_restore(nofs_flag);
720 if (!sums)
721 return BLK_STS_RESOURCE;
722
723 sums->len = bytes_left;
724 ordered = btrfs_lookup_ordered_extent(inode,
725 offset);
726 ASSERT(ordered); /* Logic error */
727 sums->bytenr = (bio->bi_iter.bi_sector << 9)
728 + total_bytes;
729 index = 0;
730 }
731
732 data = bvec_kmap_local(&bvec);
733 crypto_shash_digest(shash,
734 data + (i * fs_info->sectorsize),
735 fs_info->sectorsize,
736 sums->sums + index);
737 kunmap_local(data);
738 index += fs_info->csum_size;
739 offset += fs_info->sectorsize;
740 this_sum_bytes += fs_info->sectorsize;
741 total_bytes += fs_info->sectorsize;
742 }
743
744 }
745 this_sum_bytes = 0;
746 btrfs_add_ordered_sum(ordered, sums);
747 btrfs_put_ordered_extent(ordered);
748 return 0;
749 }
750
751 /*
752 * helper function for csum removal, this expects the
753 * key to describe the csum pointed to by the path, and it expects
754 * the csum to overlap the range [bytenr, len]
755 *
756 * The csum should not be entirely contained in the range and the
757 * range should not be entirely contained in the csum.
758 *
759 * This calls btrfs_truncate_item with the correct args based on the
760 * overlap, and fixes up the key as required.
761 */
truncate_one_csum(struct btrfs_fs_info * fs_info,struct btrfs_path * path,struct btrfs_key * key,u64 bytenr,u64 len)762 static noinline void truncate_one_csum(struct btrfs_fs_info *fs_info,
763 struct btrfs_path *path,
764 struct btrfs_key *key,
765 u64 bytenr, u64 len)
766 {
767 struct extent_buffer *leaf;
768 const u32 csum_size = fs_info->csum_size;
769 u64 csum_end;
770 u64 end_byte = bytenr + len;
771 u32 blocksize_bits = fs_info->sectorsize_bits;
772
773 leaf = path->nodes[0];
774 csum_end = btrfs_item_size(leaf, path->slots[0]) / csum_size;
775 csum_end <<= blocksize_bits;
776 csum_end += key->offset;
777
778 if (key->offset < bytenr && csum_end <= end_byte) {
779 /*
780 * [ bytenr - len ]
781 * [ ]
782 * [csum ]
783 * A simple truncate off the end of the item
784 */
785 u32 new_size = (bytenr - key->offset) >> blocksize_bits;
786 new_size *= csum_size;
787 btrfs_truncate_item(path, new_size, 1);
788 } else if (key->offset >= bytenr && csum_end > end_byte &&
789 end_byte > key->offset) {
790 /*
791 * [ bytenr - len ]
792 * [ ]
793 * [csum ]
794 * we need to truncate from the beginning of the csum
795 */
796 u32 new_size = (csum_end - end_byte) >> blocksize_bits;
797 new_size *= csum_size;
798
799 btrfs_truncate_item(path, new_size, 0);
800
801 key->offset = end_byte;
802 btrfs_set_item_key_safe(fs_info, path, key);
803 } else {
804 BUG();
805 }
806 }
807
808 /*
809 * deletes the csum items from the csum tree for a given
810 * range of bytes.
811 */
btrfs_del_csums(struct btrfs_trans_handle * trans,struct btrfs_root * root,u64 bytenr,u64 len)812 int btrfs_del_csums(struct btrfs_trans_handle *trans,
813 struct btrfs_root *root, u64 bytenr, u64 len)
814 {
815 struct btrfs_fs_info *fs_info = trans->fs_info;
816 struct btrfs_path *path;
817 struct btrfs_key key;
818 u64 end_byte = bytenr + len;
819 u64 csum_end;
820 struct extent_buffer *leaf;
821 int ret = 0;
822 const u32 csum_size = fs_info->csum_size;
823 u32 blocksize_bits = fs_info->sectorsize_bits;
824
825 ASSERT(root->root_key.objectid == BTRFS_CSUM_TREE_OBJECTID ||
826 root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID);
827
828 path = btrfs_alloc_path();
829 if (!path)
830 return -ENOMEM;
831
832 while (1) {
833 key.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
834 key.offset = end_byte - 1;
835 key.type = BTRFS_EXTENT_CSUM_KEY;
836
837 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
838 if (ret > 0) {
839 ret = 0;
840 if (path->slots[0] == 0)
841 break;
842 path->slots[0]--;
843 } else if (ret < 0) {
844 break;
845 }
846
847 leaf = path->nodes[0];
848 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
849
850 if (key.objectid != BTRFS_EXTENT_CSUM_OBJECTID ||
851 key.type != BTRFS_EXTENT_CSUM_KEY) {
852 break;
853 }
854
855 if (key.offset >= end_byte)
856 break;
857
858 csum_end = btrfs_item_size(leaf, path->slots[0]) / csum_size;
859 csum_end <<= blocksize_bits;
860 csum_end += key.offset;
861
862 /* this csum ends before we start, we're done */
863 if (csum_end <= bytenr)
864 break;
865
866 /* delete the entire item, it is inside our range */
867 if (key.offset >= bytenr && csum_end <= end_byte) {
868 int del_nr = 1;
869
870 /*
871 * Check how many csum items preceding this one in this
872 * leaf correspond to our range and then delete them all
873 * at once.
874 */
875 if (key.offset > bytenr && path->slots[0] > 0) {
876 int slot = path->slots[0] - 1;
877
878 while (slot >= 0) {
879 struct btrfs_key pk;
880
881 btrfs_item_key_to_cpu(leaf, &pk, slot);
882 if (pk.offset < bytenr ||
883 pk.type != BTRFS_EXTENT_CSUM_KEY ||
884 pk.objectid !=
885 BTRFS_EXTENT_CSUM_OBJECTID)
886 break;
887 path->slots[0] = slot;
888 del_nr++;
889 key.offset = pk.offset;
890 slot--;
891 }
892 }
893 ret = btrfs_del_items(trans, root, path,
894 path->slots[0], del_nr);
895 if (ret)
896 break;
897 if (key.offset == bytenr)
898 break;
899 } else if (key.offset < bytenr && csum_end > end_byte) {
900 unsigned long offset;
901 unsigned long shift_len;
902 unsigned long item_offset;
903 /*
904 * [ bytenr - len ]
905 * [csum ]
906 *
907 * Our bytes are in the middle of the csum,
908 * we need to split this item and insert a new one.
909 *
910 * But we can't drop the path because the
911 * csum could change, get removed, extended etc.
912 *
913 * The trick here is the max size of a csum item leaves
914 * enough room in the tree block for a single
915 * item header. So, we split the item in place,
916 * adding a new header pointing to the existing
917 * bytes. Then we loop around again and we have
918 * a nicely formed csum item that we can neatly
919 * truncate.
920 */
921 offset = (bytenr - key.offset) >> blocksize_bits;
922 offset *= csum_size;
923
924 shift_len = (len >> blocksize_bits) * csum_size;
925
926 item_offset = btrfs_item_ptr_offset(leaf,
927 path->slots[0]);
928
929 memzero_extent_buffer(leaf, item_offset + offset,
930 shift_len);
931 key.offset = bytenr;
932
933 /*
934 * btrfs_split_item returns -EAGAIN when the
935 * item changed size or key
936 */
937 ret = btrfs_split_item(trans, root, path, &key, offset);
938 if (ret && ret != -EAGAIN) {
939 btrfs_abort_transaction(trans, ret);
940 break;
941 }
942 ret = 0;
943
944 key.offset = end_byte - 1;
945 } else {
946 truncate_one_csum(fs_info, path, &key, bytenr, len);
947 if (key.offset < bytenr)
948 break;
949 }
950 btrfs_release_path(path);
951 }
952 btrfs_free_path(path);
953 return ret;
954 }
955
find_next_csum_offset(struct btrfs_root * root,struct btrfs_path * path,u64 * next_offset)956 static int find_next_csum_offset(struct btrfs_root *root,
957 struct btrfs_path *path,
958 u64 *next_offset)
959 {
960 const u32 nritems = btrfs_header_nritems(path->nodes[0]);
961 struct btrfs_key found_key;
962 int slot = path->slots[0] + 1;
963 int ret;
964
965 if (nritems == 0 || slot >= nritems) {
966 ret = btrfs_next_leaf(root, path);
967 if (ret < 0) {
968 return ret;
969 } else if (ret > 0) {
970 *next_offset = (u64)-1;
971 return 0;
972 }
973 slot = path->slots[0];
974 }
975
976 btrfs_item_key_to_cpu(path->nodes[0], &found_key, slot);
977
978 if (found_key.objectid != BTRFS_EXTENT_CSUM_OBJECTID ||
979 found_key.type != BTRFS_EXTENT_CSUM_KEY)
980 *next_offset = (u64)-1;
981 else
982 *next_offset = found_key.offset;
983
984 return 0;
985 }
986
btrfs_csum_file_blocks(struct btrfs_trans_handle * trans,struct btrfs_root * root,struct btrfs_ordered_sum * sums)987 int btrfs_csum_file_blocks(struct btrfs_trans_handle *trans,
988 struct btrfs_root *root,
989 struct btrfs_ordered_sum *sums)
990 {
991 struct btrfs_fs_info *fs_info = root->fs_info;
992 struct btrfs_key file_key;
993 struct btrfs_key found_key;
994 struct btrfs_path *path;
995 struct btrfs_csum_item *item;
996 struct btrfs_csum_item *item_end;
997 struct extent_buffer *leaf = NULL;
998 u64 next_offset;
999 u64 total_bytes = 0;
1000 u64 csum_offset;
1001 u64 bytenr;
1002 u32 ins_size;
1003 int index = 0;
1004 int found_next;
1005 int ret;
1006 const u32 csum_size = fs_info->csum_size;
1007
1008 path = btrfs_alloc_path();
1009 if (!path)
1010 return -ENOMEM;
1011 again:
1012 next_offset = (u64)-1;
1013 found_next = 0;
1014 bytenr = sums->bytenr + total_bytes;
1015 file_key.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
1016 file_key.offset = bytenr;
1017 file_key.type = BTRFS_EXTENT_CSUM_KEY;
1018
1019 item = btrfs_lookup_csum(trans, root, path, bytenr, 1);
1020 if (!IS_ERR(item)) {
1021 ret = 0;
1022 leaf = path->nodes[0];
1023 item_end = btrfs_item_ptr(leaf, path->slots[0],
1024 struct btrfs_csum_item);
1025 item_end = (struct btrfs_csum_item *)((char *)item_end +
1026 btrfs_item_size(leaf, path->slots[0]));
1027 goto found;
1028 }
1029 ret = PTR_ERR(item);
1030 if (ret != -EFBIG && ret != -ENOENT)
1031 goto out;
1032
1033 if (ret == -EFBIG) {
1034 u32 item_size;
1035 /* we found one, but it isn't big enough yet */
1036 leaf = path->nodes[0];
1037 item_size = btrfs_item_size(leaf, path->slots[0]);
1038 if ((item_size / csum_size) >=
1039 MAX_CSUM_ITEMS(fs_info, csum_size)) {
1040 /* already at max size, make a new one */
1041 goto insert;
1042 }
1043 } else {
1044 /* We didn't find a csum item, insert one. */
1045 ret = find_next_csum_offset(root, path, &next_offset);
1046 if (ret < 0)
1047 goto out;
1048 found_next = 1;
1049 goto insert;
1050 }
1051
1052 /*
1053 * At this point, we know the tree has a checksum item that ends at an
1054 * offset matching the start of the checksum range we want to insert.
1055 * We try to extend that item as much as possible and then add as many
1056 * checksums to it as they fit.
1057 *
1058 * First check if the leaf has enough free space for at least one
1059 * checksum. If it has go directly to the item extension code, otherwise
1060 * release the path and do a search for insertion before the extension.
1061 */
1062 if (btrfs_leaf_free_space(leaf) >= csum_size) {
1063 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1064 csum_offset = (bytenr - found_key.offset) >>
1065 fs_info->sectorsize_bits;
1066 goto extend_csum;
1067 }
1068
1069 btrfs_release_path(path);
1070 path->search_for_extension = 1;
1071 ret = btrfs_search_slot(trans, root, &file_key, path,
1072 csum_size, 1);
1073 path->search_for_extension = 0;
1074 if (ret < 0)
1075 goto out;
1076
1077 if (ret > 0) {
1078 if (path->slots[0] == 0)
1079 goto insert;
1080 path->slots[0]--;
1081 }
1082
1083 leaf = path->nodes[0];
1084 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1085 csum_offset = (bytenr - found_key.offset) >> fs_info->sectorsize_bits;
1086
1087 if (found_key.type != BTRFS_EXTENT_CSUM_KEY ||
1088 found_key.objectid != BTRFS_EXTENT_CSUM_OBJECTID ||
1089 csum_offset >= MAX_CSUM_ITEMS(fs_info, csum_size)) {
1090 goto insert;
1091 }
1092
1093 extend_csum:
1094 if (csum_offset == btrfs_item_size(leaf, path->slots[0]) /
1095 csum_size) {
1096 int extend_nr;
1097 u64 tmp;
1098 u32 diff;
1099
1100 tmp = sums->len - total_bytes;
1101 tmp >>= fs_info->sectorsize_bits;
1102 WARN_ON(tmp < 1);
1103 extend_nr = max_t(int, 1, tmp);
1104
1105 /*
1106 * A log tree can already have checksum items with a subset of
1107 * the checksums we are trying to log. This can happen after
1108 * doing a sequence of partial writes into prealloc extents and
1109 * fsyncs in between, with a full fsync logging a larger subrange
1110 * of an extent for which a previous fast fsync logged a smaller
1111 * subrange. And this happens in particular due to merging file
1112 * extent items when we complete an ordered extent for a range
1113 * covered by a prealloc extent - this is done at
1114 * btrfs_mark_extent_written().
1115 *
1116 * So if we try to extend the previous checksum item, which has
1117 * a range that ends at the start of the range we want to insert,
1118 * make sure we don't extend beyond the start offset of the next
1119 * checksum item. If we are at the last item in the leaf, then
1120 * forget the optimization of extending and add a new checksum
1121 * item - it is not worth the complexity of releasing the path,
1122 * getting the first key for the next leaf, repeat the btree
1123 * search, etc, because log trees are temporary anyway and it
1124 * would only save a few bytes of leaf space.
1125 */
1126 if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) {
1127 if (path->slots[0] + 1 >=
1128 btrfs_header_nritems(path->nodes[0])) {
1129 ret = find_next_csum_offset(root, path, &next_offset);
1130 if (ret < 0)
1131 goto out;
1132 found_next = 1;
1133 goto insert;
1134 }
1135
1136 ret = find_next_csum_offset(root, path, &next_offset);
1137 if (ret < 0)
1138 goto out;
1139
1140 tmp = (next_offset - bytenr) >> fs_info->sectorsize_bits;
1141 if (tmp <= INT_MAX)
1142 extend_nr = min_t(int, extend_nr, tmp);
1143 }
1144
1145 diff = (csum_offset + extend_nr) * csum_size;
1146 diff = min(diff,
1147 MAX_CSUM_ITEMS(fs_info, csum_size) * csum_size);
1148
1149 diff = diff - btrfs_item_size(leaf, path->slots[0]);
1150 diff = min_t(u32, btrfs_leaf_free_space(leaf), diff);
1151 diff /= csum_size;
1152 diff *= csum_size;
1153
1154 btrfs_extend_item(path, diff);
1155 ret = 0;
1156 goto csum;
1157 }
1158
1159 insert:
1160 btrfs_release_path(path);
1161 csum_offset = 0;
1162 if (found_next) {
1163 u64 tmp;
1164
1165 tmp = sums->len - total_bytes;
1166 tmp >>= fs_info->sectorsize_bits;
1167 tmp = min(tmp, (next_offset - file_key.offset) >>
1168 fs_info->sectorsize_bits);
1169
1170 tmp = max_t(u64, 1, tmp);
1171 tmp = min_t(u64, tmp, MAX_CSUM_ITEMS(fs_info, csum_size));
1172 ins_size = csum_size * tmp;
1173 } else {
1174 ins_size = csum_size;
1175 }
1176 ret = btrfs_insert_empty_item(trans, root, path, &file_key,
1177 ins_size);
1178 if (ret < 0)
1179 goto out;
1180 if (WARN_ON(ret != 0))
1181 goto out;
1182 leaf = path->nodes[0];
1183 csum:
1184 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_csum_item);
1185 item_end = (struct btrfs_csum_item *)((unsigned char *)item +
1186 btrfs_item_size(leaf, path->slots[0]));
1187 item = (struct btrfs_csum_item *)((unsigned char *)item +
1188 csum_offset * csum_size);
1189 found:
1190 ins_size = (u32)(sums->len - total_bytes) >> fs_info->sectorsize_bits;
1191 ins_size *= csum_size;
1192 ins_size = min_t(u32, (unsigned long)item_end - (unsigned long)item,
1193 ins_size);
1194 write_extent_buffer(leaf, sums->sums + index, (unsigned long)item,
1195 ins_size);
1196
1197 index += ins_size;
1198 ins_size /= csum_size;
1199 total_bytes += ins_size * fs_info->sectorsize;
1200
1201 btrfs_mark_buffer_dirty(path->nodes[0]);
1202 if (total_bytes < sums->len) {
1203 btrfs_release_path(path);
1204 cond_resched();
1205 goto again;
1206 }
1207 out:
1208 btrfs_free_path(path);
1209 return ret;
1210 }
1211
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)1212 void btrfs_extent_item_to_extent_map(struct btrfs_inode *inode,
1213 const struct btrfs_path *path,
1214 struct btrfs_file_extent_item *fi,
1215 const bool new_inline,
1216 struct extent_map *em)
1217 {
1218 struct btrfs_fs_info *fs_info = inode->root->fs_info;
1219 struct btrfs_root *root = inode->root;
1220 struct extent_buffer *leaf = path->nodes[0];
1221 const int slot = path->slots[0];
1222 struct btrfs_key key;
1223 u64 extent_start, extent_end;
1224 u64 bytenr;
1225 u8 type = btrfs_file_extent_type(leaf, fi);
1226 int compress_type = btrfs_file_extent_compression(leaf, fi);
1227
1228 btrfs_item_key_to_cpu(leaf, &key, slot);
1229 extent_start = key.offset;
1230 extent_end = btrfs_file_extent_end(path);
1231 em->ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi);
1232 em->generation = btrfs_file_extent_generation(leaf, fi);
1233 if (type == BTRFS_FILE_EXTENT_REG ||
1234 type == BTRFS_FILE_EXTENT_PREALLOC) {
1235 em->start = extent_start;
1236 em->len = extent_end - extent_start;
1237 em->orig_start = extent_start -
1238 btrfs_file_extent_offset(leaf, fi);
1239 em->orig_block_len = btrfs_file_extent_disk_num_bytes(leaf, fi);
1240 bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
1241 if (bytenr == 0) {
1242 em->block_start = EXTENT_MAP_HOLE;
1243 return;
1244 }
1245 if (compress_type != BTRFS_COMPRESS_NONE) {
1246 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
1247 em->compress_type = compress_type;
1248 em->block_start = bytenr;
1249 em->block_len = em->orig_block_len;
1250 } else {
1251 bytenr += btrfs_file_extent_offset(leaf, fi);
1252 em->block_start = bytenr;
1253 em->block_len = em->len;
1254 if (type == BTRFS_FILE_EXTENT_PREALLOC)
1255 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
1256 }
1257 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
1258 em->block_start = EXTENT_MAP_INLINE;
1259 em->start = extent_start;
1260 em->len = extent_end - extent_start;
1261 /*
1262 * Initialize orig_start and block_len with the same values
1263 * as in inode.c:btrfs_get_extent().
1264 */
1265 em->orig_start = EXTENT_MAP_HOLE;
1266 em->block_len = (u64)-1;
1267 if (!new_inline && compress_type != BTRFS_COMPRESS_NONE) {
1268 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
1269 em->compress_type = compress_type;
1270 }
1271 } else {
1272 btrfs_err(fs_info,
1273 "unknown file extent item type %d, inode %llu, offset %llu, "
1274 "root %llu", type, btrfs_ino(inode), extent_start,
1275 root->root_key.objectid);
1276 }
1277 }
1278
1279 /*
1280 * Returns the end offset (non inclusive) of the file extent item the given path
1281 * points to. If it points to an inline extent, the returned offset is rounded
1282 * up to the sector size.
1283 */
btrfs_file_extent_end(const struct btrfs_path * path)1284 u64 btrfs_file_extent_end(const struct btrfs_path *path)
1285 {
1286 const struct extent_buffer *leaf = path->nodes[0];
1287 const int slot = path->slots[0];
1288 struct btrfs_file_extent_item *fi;
1289 struct btrfs_key key;
1290 u64 end;
1291
1292 btrfs_item_key_to_cpu(leaf, &key, slot);
1293 ASSERT(key.type == BTRFS_EXTENT_DATA_KEY);
1294 fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
1295
1296 if (btrfs_file_extent_type(leaf, fi) == BTRFS_FILE_EXTENT_INLINE) {
1297 end = btrfs_file_extent_ram_bytes(leaf, fi);
1298 end = ALIGN(key.offset + end, leaf->fs_info->sectorsize);
1299 } else {
1300 end = key.offset + btrfs_file_extent_num_bytes(leaf, fi);
1301 }
1302
1303 return end;
1304 }
1305