projects / linux-2.6-block.git / blame
? search:
summary | shortlog | log | commit | commitdiff | tree
blob | blame (incremental) | history | HEAD
btrfs: Change qgroup_meta_rsv to 64bit
[linux-2.6-block.git] / fs / btrfs / send.c
CommitLineData
31db9f7c
AB		 1/*
2 * Copyright (C) 2012 Alexander Block. 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/bsearch.h>
20#include <linux/fs.h>
21#include <linux/file.h>
22#include <linux/sort.h>
23#include <linux/mount.h>
24#include <linux/xattr.h>
25#include <linux/posix_acl_xattr.h>
26#include <linux/radix-tree.h>
a1857ebe 27#include <linux/vmalloc.h>
ed84885d 28#include <linux/string.h>
31db9f7c
AB		 29
30#include "send.h"
31#include "backref.h"
0b947aff 32#include "hash.h"
31db9f7c
AB		 33#include "locking.h"
34#include "disk-io.h"
35#include "btrfs_inode.h"
36#include "transaction.h"
ebb8765b 37#include "compression.h"
31db9f7c 38
31db9f7c
AB		 39/*
40 * A fs_path is a helper to dynamically build path names with unknown size.
41 * It reallocates the internal buffer on demand.
42 * It allows fast adding of path elements on the right side (normal path) and
43 * fast adding to the left side (reversed path). A reversed path can also be
44 * unreversed if needed.
45 */
46struct fs_path {
47 union {
48 struct {
49 char *start;
50 char *end;
31db9f7c
AB		 51
52 char *buf;
1f5a7ff9
DS		 53 unsigned short buf_len:15;
54 unsigned short reversed:1;
31db9f7c
AB		 55 char inline_buf[];
56 };
ace01050
DS		 57 /*
58 * Average path length does not exceed 200 bytes, we'll have
59 * better packing in the slab and higher chance to satisfy
60 * a allocation later during send.
61 */
62 char pad[256];
31db9f7c
AB		 63 };
64};
65#define FS_PATH_INLINE_SIZE \
66 (sizeof(struct fs_path) - offsetof(struct fs_path, inline_buf))
67
68
69/* reused for each extent */
70struct clone_root {
71 struct btrfs_root *root;
72 u64 ino;
73 u64 offset;
74
75 u64 found_refs;
76};
77
78#define SEND_CTX_MAX_NAME_CACHE_SIZE 128
79#define SEND_CTX_NAME_CACHE_CLEAN_SIZE (SEND_CTX_MAX_NAME_CACHE_SIZE * 2)
80
81struct send_ctx {
82 struct file *send_filp;
83 loff_t send_off;
84 char *send_buf;
85 u32 send_size;
86 u32 send_max_size;
87 u64 total_send_size;
88 u64 cmd_send_size[BTRFS_SEND_C_MAX + 1];
cb95e7bf 89 u64 flags; /* 'flags' member of btrfs_ioctl_send_args is u64 */
31db9f7c 90
31db9f7c
AB		 91 struct btrfs_root *send_root;
92 struct btrfs_root *parent_root;
93 struct clone_root *clone_roots;
94 int clone_roots_cnt;
95
96 /* current state of the compare_tree call */
97 struct btrfs_path *left_path;
98 struct btrfs_path *right_path;
99 struct btrfs_key *cmp_key;
100
101 /*
102 * infos of the currently processed inode. In case of deleted inodes,
103 * these are the values from the deleted inode.
104 */
105 u64 cur_ino;
106 u64 cur_inode_gen;
107 int cur_inode_new;
108 int cur_inode_new_gen;
109 int cur_inode_deleted;
31db9f7c
AB		 110 u64 cur_inode_size;
111 u64 cur_inode_mode;
644d1940 112 u64 cur_inode_rdev;
16e7549f 113 u64 cur_inode_last_extent;
31db9f7c
AB		 114
115 u64 send_progress;
116
117 struct list_head new_refs;
118 struct list_head deleted_refs;
119
120 struct radix_tree_root name_cache;
121 struct list_head name_cache_list;
122 int name_cache_size;
123
2131bcd3
LB		 124 struct file_ra_state ra;
125
31db9f7c 126 char *read_buf;
9f03740a
FDBM		 127
128 /*
129 * We process inodes by their increasing order, so if before an
130 * incremental send we reverse the parent/child relationship of
131 * directories such that a directory with a lower inode number was
132 * the parent of a directory with a higher inode number, and the one
133 * becoming the new parent got renamed too, we can't rename/move the
134 * directory with lower inode number when we finish processing it - we
135 * must process the directory with higher inode number first, then
136 * rename/move it and then rename/move the directory with lower inode
137 * number. Example follows.
138 *
139 * Tree state when the first send was performed:
140 *
141 * .
142 * |-- a (ino 257)
143 * |-- b (ino 258)
144 * |
145 * |
146 * |-- c (ino 259)
147 * | |-- d (ino 260)
148 * |
149 * |-- c2 (ino 261)
150 *
151 * Tree state when the second (incremental) send is performed:
152 *
153 * .
154 * |-- a (ino 257)
155 * |-- b (ino 258)
156 * |-- c2 (ino 261)
157 * |-- d2 (ino 260)
158 * |-- cc (ino 259)
159 *
160 * The sequence of steps that lead to the second state was:
161 *
162 * mv /a/b/c/d /a/b/c2/d2
163 * mv /a/b/c /a/b/c2/d2/cc
164 *
165 * "c" has lower inode number, but we can't move it (2nd mv operation)
166 * before we move "d", which has higher inode number.
167 *
168 * So we just memorize which move/rename operations must be performed
169 * later when their respective parent is processed and moved/renamed.
170 */
171
172 /* Indexed by parent directory inode number. */
173 struct rb_root pending_dir_moves;
174
175 /*
176 * Reverse index, indexed by the inode number of a directory that
177 * is waiting for the move/rename of its immediate parent before its
178 * own move/rename can be performed.
179 */
180 struct rb_root waiting_dir_moves;
9dc44214
FM		 181
182 /*
183 * A directory that is going to be rm'ed might have a child directory
184 * which is in the pending directory moves index above. In this case,
185 * the directory can only be removed after the move/rename of its child
186 * is performed. Example:
187 *
188 * Parent snapshot:
189 *
190 * . (ino 256)
191 * |-- a/ (ino 257)
192 * |-- b/ (ino 258)
193 * |-- c/ (ino 259)
194 * | |-- x/ (ino 260)
195 * |
196 * |-- y/ (ino 261)
197 *
198 * Send snapshot:
199 *
200 * . (ino 256)
201 * |-- a/ (ino 257)
202 * |-- b/ (ino 258)
203 * |-- YY/ (ino 261)
204 * |-- x/ (ino 260)
205 *
206 * Sequence of steps that lead to the send snapshot:
207 * rm -f /a/b/c/foo.txt
208 * mv /a/b/y /a/b/YY
209 * mv /a/b/c/x /a/b/YY
210 * rmdir /a/b/c
211 *
212 * When the child is processed, its move/rename is delayed until its
213 * parent is processed (as explained above), but all other operations
214 * like update utimes, chown, chgrp, etc, are performed and the paths
215 * that it uses for those operations must use the orphanized name of
216 * its parent (the directory we're going to rm later), so we need to
217 * memorize that name.
218 *
219 * Indexed by the inode number of the directory to be deleted.
220 */
221 struct rb_root orphan_dirs;
9f03740a
FDBM		 222};
223
224struct pending_dir_move {
225 struct rb_node node;
226 struct list_head list;
227 u64 parent_ino;
228 u64 ino;
229 u64 gen;
230 struct list_head update_refs;
231};
232
233struct waiting_dir_move {
234 struct rb_node node;
235 u64 ino;
9dc44214
FM		 236 /*
237 * There might be some directory that could not be removed because it
238 * was waiting for this directory inode to be moved first. Therefore
239 * after this directory is moved, we can try to rmdir the ino rmdir_ino.
240 */
241 u64 rmdir_ino;
8b191a68 242 bool orphanized;
9dc44214
FM		 243};
244
245struct orphan_dir_info {
246 struct rb_node node;
247 u64 ino;
248 u64 gen;
31db9f7c
AB		 249};
250
251struct name_cache_entry {
252 struct list_head list;
7e0926fe
AB		 253 /*
254 * radix_tree has only 32bit entries but we need to handle 64bit inums.
255 * We use the lower 32bit of the 64bit inum to store it in the tree. If
256 * more then one inum would fall into the same entry, we use radix_list
257 * to store the additional entries. radix_list is also used to store
258 * entries where two entries have the same inum but different
259 * generations.
260 */
261 struct list_head radix_list;
31db9f7c
AB		 262 u64 ino;
263 u64 gen;
264 u64 parent_ino;
265 u64 parent_gen;
266 int ret;
267 int need_later_update;
268 int name_len;
269 char name[];
270};
271
95155585
FM		 272static void inconsistent_snapshot_error(struct send_ctx *sctx,
273 enum btrfs_compare_tree_result result,
274 const char *what)
275{
276 const char *result_string;
277
278 switch (result) {
279 case BTRFS_COMPARE_TREE_NEW:
280 result_string = "new";
281 break;
282 case BTRFS_COMPARE_TREE_DELETED:
283 result_string = "deleted";
284 break;
285 case BTRFS_COMPARE_TREE_CHANGED:
286 result_string = "updated";
287 break;
288 case BTRFS_COMPARE_TREE_SAME:
289 ASSERT(0);
290 result_string = "unchanged";
291 break;
292 default:
293 ASSERT(0);
294 result_string = "unexpected";
295 }
296
297 btrfs_err(sctx->send_root->fs_info,
298 "Send: inconsistent snapshot, found %s %s for inode %llu without updated inode item, send root is %llu, parent root is %llu",
299 result_string, what, sctx->cmp_key->objectid,
300 sctx->send_root->root_key.objectid,
301 (sctx->parent_root ?
302 sctx->parent_root->root_key.objectid : 0));
303}
304
9f03740a
FDBM		 305static int is_waiting_for_move(struct send_ctx *sctx, u64 ino);
306
9dc44214
FM		 307static struct waiting_dir_move *
308get_waiting_dir_move(struct send_ctx *sctx, u64 ino);
309
310static int is_waiting_for_rm(struct send_ctx *sctx, u64 dir_ino);
311
16e7549f
JB		 312static int need_send_hole(struct send_ctx *sctx)
313{
314 return (sctx->parent_root && !sctx->cur_inode_new &&
315 !sctx->cur_inode_new_gen && !sctx->cur_inode_deleted &&
316 S_ISREG(sctx->cur_inode_mode));
317}
318
31db9f7c
AB		 319static void fs_path_reset(struct fs_path *p)
320{
321 if (p->reversed) {
322 p->start = p->buf + p->buf_len - 1;
323 p->end = p->start;
324 *p->start = 0;
325 } else {
326 p->start = p->buf;
327 p->end = p->start;
328 *p->start = 0;
329 }
330}
331
924794c9 332static struct fs_path *fs_path_alloc(void)
31db9f7c
AB		 333{
334 struct fs_path *p;
335
e780b0d1 336 p = kmalloc(sizeof(*p), GFP_KERNEL);
31db9f7c
AB		 337 if (!p)
338 return NULL;
339 p->reversed = 0;
31db9f7c
AB		 340 p->buf = p->inline_buf;
341 p->buf_len = FS_PATH_INLINE_SIZE;
342 fs_path_reset(p);
343 return p;
344}
345
924794c9 346static struct fs_path *fs_path_alloc_reversed(void)
31db9f7c
AB		 347{
348 struct fs_path *p;
349
924794c9 350 p = fs_path_alloc();
31db9f7c
AB		 351 if (!p)
352 return NULL;
353 p->reversed = 1;
354 fs_path_reset(p);
355 return p;
356}
357
924794c9 358static void fs_path_free(struct fs_path *p)
31db9f7c
AB		 359{
360 if (!p)
361 return;
ace01050
DS		 362 if (p->buf != p->inline_buf)
363 kfree(p->buf);
31db9f7c
AB		 364 kfree(p);
365}
366
367static int fs_path_len(struct fs_path *p)
368{
369 return p->end - p->start;
370}
371
372static int fs_path_ensure_buf(struct fs_path *p, int len)
373{
374 char *tmp_buf;
375 int path_len;
376 int old_buf_len;
377
378 len++;
379
380 if (p->buf_len >= len)
381 return 0;
382
cfd4a535
CM		 383 if (len > PATH_MAX) {
384 WARN_ON(1);
385 return -ENOMEM;
386 }
387
1b2782c8
DS		 388 path_len = p->end - p->start;
389 old_buf_len = p->buf_len;
390
ace01050
DS		 391 /*
392 * First time the inline_buf does not suffice
393 */
01a9a8a9 394 if (p->buf == p->inline_buf) {
e780b0d1 395 tmp_buf = kmalloc(len, GFP_KERNEL);
01a9a8a9
FM		 396 if (tmp_buf)
397 memcpy(tmp_buf, p->buf, old_buf_len);
398 } else {
e780b0d1 399 tmp_buf = krealloc(p->buf, len, GFP_KERNEL);
01a9a8a9 400 }
9c9ca00b
DS		 401 if (!tmp_buf)
402 return -ENOMEM;
403 p->buf = tmp_buf;
404 /*
405 * The real size of the buffer is bigger, this will let the fast path
406 * happen most of the time
407 */
408 p->buf_len = ksize(p->buf);
ace01050 409
31db9f7c
AB		 410 if (p->reversed) {
411 tmp_buf = p->buf + old_buf_len - path_len - 1;
412 p->end = p->buf + p->buf_len - 1;
413 p->start = p->end - path_len;
414 memmove(p->start, tmp_buf, path_len + 1);
415 } else {
416 p->start = p->buf;
417 p->end = p->start + path_len;
418 }
419 return 0;
420}
421
b23ab57d
DS		 422static int fs_path_prepare_for_add(struct fs_path *p, int name_len,
423 char **prepared)
31db9f7c
AB		 424{
425 int ret;
426 int new_len;
427
428 new_len = p->end - p->start + name_len;
429 if (p->start != p->end)
430 new_len++;
431 ret = fs_path_ensure_buf(p, new_len);
432 if (ret < 0)
433 goto out;
434
435 if (p->reversed) {
436 if (p->start != p->end)
437 *--p->start = '/';
438 p->start -= name_len;
b23ab57d 439 *prepared = p->start;
31db9f7c
AB		 440 } else {
441 if (p->start != p->end)
442 *p->end++ = '/';
b23ab57d 443 *prepared = p->end;
31db9f7c
AB		 444 p->end += name_len;
445 *p->end = 0;
446 }
447
448out:
449 return ret;
450}
451
452static int fs_path_add(struct fs_path *p, const char *name, int name_len)
453{
454 int ret;
b23ab57d 455 char *prepared;
31db9f7c 456
b23ab57d 457 ret = fs_path_prepare_for_add(p, name_len, &prepared);
31db9f7c
AB		 458 if (ret < 0)
459 goto out;
b23ab57d 460 memcpy(prepared, name, name_len);
31db9f7c
AB		 461
462out:
463 return ret;
464}
465
466static int fs_path_add_path(struct fs_path *p, struct fs_path *p2)
467{
468 int ret;
b23ab57d 469 char *prepared;
31db9f7c 470
b23ab57d 471 ret = fs_path_prepare_for_add(p, p2->end - p2->start, &prepared);
31db9f7c
AB		 472 if (ret < 0)
473 goto out;
b23ab57d 474 memcpy(prepared, p2->start, p2->end - p2->start);
31db9f7c
AB		 475
476out:
477 return ret;
478}
479
480static int fs_path_add_from_extent_buffer(struct fs_path *p,
481 struct extent_buffer *eb,
482 unsigned long off, int len)
483{
484 int ret;
b23ab57d 485 char *prepared;
31db9f7c 486
b23ab57d 487 ret = fs_path_prepare_for_add(p, len, &prepared);
31db9f7c
AB		 488 if (ret < 0)
489 goto out;
490
b23ab57d 491 read_extent_buffer(eb, prepared, off, len);
31db9f7c
AB		 492
493out:
494 return ret;
495}
496
31db9f7c
AB		 497static int fs_path_copy(struct fs_path *p, struct fs_path *from)
498{
499 int ret;
500
501 p->reversed = from->reversed;
502 fs_path_reset(p);
503
504 ret = fs_path_add_path(p, from);
505
506 return ret;
507}
508
509
510static void fs_path_unreverse(struct fs_path *p)
511{
512 char *tmp;
513 int len;
514
515 if (!p->reversed)
516 return;
517
518 tmp = p->start;
519 len = p->end - p->start;
520 p->start = p->buf;
521 p->end = p->start + len;
522 memmove(p->start, tmp, len + 1);
523 p->reversed = 0;
524}
525
526static struct btrfs_path *alloc_path_for_send(void)
527{
528 struct btrfs_path *path;
529
530 path = btrfs_alloc_path();
531 if (!path)
532 return NULL;
533 path->search_commit_root = 1;
534 path->skip_locking = 1;
3f8a18cc 535 path->need_commit_sem = 1;
31db9f7c
AB		 536 return path;
537}
538
48a3b636 539static int write_buf(struct file *filp, const void *buf, u32 len, loff_t *off)
31db9f7c
AB		 540{
541 int ret;
542 mm_segment_t old_fs;
543 u32 pos = 0;
544
545 old_fs = get_fs();
546 set_fs(KERNEL_DS);
547
548 while (pos < len) {
d447d0da
FF		 549 ret = vfs_write(filp, (__force const char __user *)buf + pos,
550 len - pos, off);
31db9f7c
AB		 551 /* TODO handle that correctly */
552 /*if (ret == -ERESTARTSYS) {
553 continue;
554 }*/
555 if (ret < 0)
556 goto out;
557 if (ret == 0) {
558 ret = -EIO;
559 goto out;
560 }
561 pos += ret;
562 }
563
564 ret = 0;
565
566out:
567 set_fs(old_fs);
568 return ret;
569}
570
571static int tlv_put(struct send_ctx *sctx, u16 attr, const void *data, int len)
572{
573 struct btrfs_tlv_header *hdr;
574 int total_len = sizeof(*hdr) + len;
575 int left = sctx->send_max_size - sctx->send_size;
576
577 if (unlikely(left < total_len))
578 return -EOVERFLOW;
579
580 hdr = (struct btrfs_tlv_header *) (sctx->send_buf + sctx->send_size);
581 hdr->tlv_type = cpu_to_le16(attr);
582 hdr->tlv_len = cpu_to_le16(len);
583 memcpy(hdr + 1, data, len);
584 sctx->send_size += total_len;
585
586 return 0;
587}
588
95bc79d5
DS		 589#define TLV_PUT_DEFINE_INT(bits) \
590 static int tlv_put_u##bits(struct send_ctx *sctx, \
591 u##bits attr, u##bits value) \
592 { \
593 __le##bits __tmp = cpu_to_le##bits(value); \
594 return tlv_put(sctx, attr, &__tmp, sizeof(__tmp)); \
595 }
31db9f7c 596
95bc79d5 597TLV_PUT_DEFINE_INT(64)
31db9f7c
AB		 598
599static int tlv_put_string(struct send_ctx *sctx, u16 attr,
600 const char *str, int len)
601{
602 if (len == -1)
603 len = strlen(str);
604 return tlv_put(sctx, attr, str, len);
605}
606
607static int tlv_put_uuid(struct send_ctx *sctx, u16 attr,
608 const u8 *uuid)
609{
610 return tlv_put(sctx, attr, uuid, BTRFS_UUID_SIZE);
611}
612
31db9f7c
AB		 613static int tlv_put_btrfs_timespec(struct send_ctx *sctx, u16 attr,
614 struct extent_buffer *eb,
615 struct btrfs_timespec *ts)
616{
617 struct btrfs_timespec bts;
618 read_extent_buffer(eb, &bts, (unsigned long)ts, sizeof(bts));
619 return tlv_put(sctx, attr, &bts, sizeof(bts));
620}
621
622
623#define TLV_PUT(sctx, attrtype, attrlen, data) \
624 do { \
625 ret = tlv_put(sctx, attrtype, attrlen, data); \
626 if (ret < 0) \
627 goto tlv_put_failure; \
628 } while (0)
629
630#define TLV_PUT_INT(sctx, attrtype, bits, value) \
631 do { \
632 ret = tlv_put_u##bits(sctx, attrtype, value); \
633 if (ret < 0) \
634 goto tlv_put_failure; \
635 } while (0)
636
637#define TLV_PUT_U8(sctx, attrtype, data) TLV_PUT_INT(sctx, attrtype, 8, data)
638#define TLV_PUT_U16(sctx, attrtype, data) TLV_PUT_INT(sctx, attrtype, 16, data)
639#define TLV_PUT_U32(sctx, attrtype, data) TLV_PUT_INT(sctx, attrtype, 32, data)
640#define TLV_PUT_U64(sctx, attrtype, data) TLV_PUT_INT(sctx, attrtype, 64, data)
641#define TLV_PUT_STRING(sctx, attrtype, str, len) \
642 do { \
643 ret = tlv_put_string(sctx, attrtype, str, len); \
644 if (ret < 0) \
645 goto tlv_put_failure; \
646 } while (0)
647#define TLV_PUT_PATH(sctx, attrtype, p) \
648 do { \
649 ret = tlv_put_string(sctx, attrtype, p->start, \
650 p->end - p->start); \
651 if (ret < 0) \
652 goto tlv_put_failure; \
653 } while(0)
654#define TLV_PUT_UUID(sctx, attrtype, uuid) \
655 do { \
656 ret = tlv_put_uuid(sctx, attrtype, uuid); \
657 if (ret < 0) \
658 goto tlv_put_failure; \
659 } while (0)
31db9f7c
AB		 660#define TLV_PUT_BTRFS_TIMESPEC(sctx, attrtype, eb, ts) \
661 do { \
662 ret = tlv_put_btrfs_timespec(sctx, attrtype, eb, ts); \
663 if (ret < 0) \
664 goto tlv_put_failure; \
665 } while (0)
666
667static int send_header(struct send_ctx *sctx)
668{
669 struct btrfs_stream_header hdr;
670
671 strcpy(hdr.magic, BTRFS_SEND_STREAM_MAGIC);
672 hdr.version = cpu_to_le32(BTRFS_SEND_STREAM_VERSION);
673
1bcea355
AJ		 674 return write_buf(sctx->send_filp, &hdr, sizeof(hdr),
675 &sctx->send_off);
31db9f7c
AB		 676}
677
678/*
679 * For each command/item we want to send to userspace, we call this function.
680 */
681static int begin_cmd(struct send_ctx *sctx, int cmd)
682{
683 struct btrfs_cmd_header *hdr;
684
fae7f21c 685 if (WARN_ON(!sctx->send_buf))
31db9f7c 686 return -EINVAL;
31db9f7c
AB		 687
688 BUG_ON(sctx->send_size);
689
690 sctx->send_size += sizeof(*hdr);
691 hdr = (struct btrfs_cmd_header *)sctx->send_buf;
692 hdr->cmd = cpu_to_le16(cmd);
693
694 return 0;
695}
696
697static int send_cmd(struct send_ctx *sctx)
698{
699 int ret;
700 struct btrfs_cmd_header *hdr;
701 u32 crc;
702
703 hdr = (struct btrfs_cmd_header *)sctx->send_buf;
704 hdr->len = cpu_to_le32(sctx->send_size - sizeof(*hdr));
705 hdr->crc = 0;
706
0b947aff 707 crc = btrfs_crc32c(0, (unsigned char *)sctx->send_buf, sctx->send_size);
31db9f7c
AB		 708 hdr->crc = cpu_to_le32(crc);
709
1bcea355
AJ		 710 ret = write_buf(sctx->send_filp, sctx->send_buf, sctx->send_size,
711 &sctx->send_off);
31db9f7c
AB		 712
713 sctx->total_send_size += sctx->send_size;
714 sctx->cmd_send_size[le16_to_cpu(hdr->cmd)] += sctx->send_size;
715 sctx->send_size = 0;
716
717 return ret;
718}
719
720/*
721 * Sends a move instruction to user space
722 */
723static int send_rename(struct send_ctx *sctx,
724 struct fs_path *from, struct fs_path *to)
725{
04ab956e 726 struct btrfs_fs_info *fs_info = sctx->send_root->fs_info;
31db9f7c
AB		 727 int ret;
728
04ab956e 729 btrfs_debug(fs_info, "send_rename %s -> %s", from->start, to->start);
31db9f7c
AB		 730
731 ret = begin_cmd(sctx, BTRFS_SEND_C_RENAME);
732 if (ret < 0)
733 goto out;
734
735 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, from);
736 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH_TO, to);
737
738 ret = send_cmd(sctx);
739
740tlv_put_failure:
741out:
742 return ret;
743}
744
745/*
746 * Sends a link instruction to user space
747 */
748static int send_link(struct send_ctx *sctx,
749 struct fs_path *path, struct fs_path *lnk)
750{
04ab956e 751 struct btrfs_fs_info *fs_info = sctx->send_root->fs_info;
31db9f7c
AB		 752 int ret;
753
04ab956e 754 btrfs_debug(fs_info, "send_link %s -> %s", path->start, lnk->start);
31db9f7c
AB		 755
756 ret = begin_cmd(sctx, BTRFS_SEND_C_LINK);
757 if (ret < 0)
758 goto out;
759
760 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, path);
761 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH_LINK, lnk);
762
763 ret = send_cmd(sctx);
764
765tlv_put_failure:
766out:
767 return ret;
768}
769
770/*
771 * Sends an unlink instruction to user space
772 */
773static int send_unlink(struct send_ctx *sctx, struct fs_path *path)
774{
04ab956e 775 struct btrfs_fs_info *fs_info = sctx->send_root->fs_info;
31db9f7c
AB		 776 int ret;
777
04ab956e 778 btrfs_debug(fs_info, "send_unlink %s", path->start);
31db9f7c
AB		 779
780 ret = begin_cmd(sctx, BTRFS_SEND_C_UNLINK);
781 if (ret < 0)
782 goto out;
783
784 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, path);
785
786 ret = send_cmd(sctx);
787
788tlv_put_failure:
789out:
790 return ret;
791}
792
793/*
794 * Sends a rmdir instruction to user space
795 */
796static int send_rmdir(struct send_ctx *sctx, struct fs_path *path)
797{
04ab956e 798 struct btrfs_fs_info *fs_info = sctx->send_root->fs_info;
31db9f7c
AB		 799 int ret;
800
04ab956e 801 btrfs_debug(fs_info, "send_rmdir %s", path->start);
31db9f7c
AB		 802
803 ret = begin_cmd(sctx, BTRFS_SEND_C_RMDIR);
804 if (ret < 0)
805 goto out;
806
807 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, path);
808
809 ret = send_cmd(sctx);
810
811tlv_put_failure:
812out:
813 return ret;
814}
815
816/*
817 * Helper function to retrieve some fields from an inode item.
818 */
3f8a18cc
JB		 819static int __get_inode_info(struct btrfs_root *root, struct btrfs_path *path,
820 u64 ino, u64 *size, u64 *gen, u64 *mode, u64 *uid,
821 u64 *gid, u64 *rdev)
31db9f7c
AB		 822{
823 int ret;
824 struct btrfs_inode_item *ii;
825 struct btrfs_key key;
31db9f7c
AB		 826
827 key.objectid = ino;
828 key.type = BTRFS_INODE_ITEM_KEY;
829 key.offset = 0;
830 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
31db9f7c 831 if (ret) {
3f8a18cc
JB		 832 if (ret > 0)
833 ret = -ENOENT;
834 return ret;
31db9f7c
AB		 835 }
836
837 ii = btrfs_item_ptr(path->nodes[0], path->slots[0],
838 struct btrfs_inode_item);
839 if (size)
840 *size = btrfs_inode_size(path->nodes[0], ii);
841 if (gen)
842 *gen = btrfs_inode_generation(path->nodes[0], ii);
843 if (mode)
844 *mode = btrfs_inode_mode(path->nodes[0], ii);
845 if (uid)
846 *uid = btrfs_inode_uid(path->nodes[0], ii);
847 if (gid)
848 *gid = btrfs_inode_gid(path->nodes[0], ii);
85a7b33b
AB		 849 if (rdev)
850 *rdev = btrfs_inode_rdev(path->nodes[0], ii);
31db9f7c 851
3f8a18cc
JB		 852 return ret;
853}
854
855static int get_inode_info(struct btrfs_root *root,
856 u64 ino, u64 *size, u64 *gen,
857 u64 *mode, u64 *uid, u64 *gid,
858 u64 *rdev)
859{
860 struct btrfs_path *path;
861 int ret;
862
863 path = alloc_path_for_send();
864 if (!path)
865 return -ENOMEM;
866 ret = __get_inode_info(root, path, ino, size, gen, mode, uid, gid,
867 rdev);
31db9f7c
AB		 868 btrfs_free_path(path);
869 return ret;
870}
871
872typedef int (*iterate_inode_ref_t)(int num, u64 dir, int index,
873 struct fs_path *p,
874 void *ctx);
875
876/*
96b5bd77
JS		 877 * Helper function to iterate the entries in ONE btrfs_inode_ref or
878 * btrfs_inode_extref.
31db9f7c
AB		 879 * The iterate callback may return a non zero value to stop iteration. This can
880 * be a negative value for error codes or 1 to simply stop it.
881 *
96b5bd77 882 * path must point to the INODE_REF or INODE_EXTREF when called.
31db9f7c 883 */
924794c9 884static int iterate_inode_ref(struct btrfs_root *root, struct btrfs_path *path,
31db9f7c
AB		 885 struct btrfs_key *found_key, int resolve,
886 iterate_inode_ref_t iterate, void *ctx)
887{
96b5bd77 888 struct extent_buffer *eb = path->nodes[0];
31db9f7c
AB		 889 struct btrfs_item *item;
890 struct btrfs_inode_ref *iref;
96b5bd77 891 struct btrfs_inode_extref *extref;
31db9f7c
AB		 892 struct btrfs_path *tmp_path;
893 struct fs_path *p;
96b5bd77 894 u32 cur = 0;
31db9f7c 895 u32 total;
96b5bd77 896 int slot = path->slots[0];
31db9f7c
AB		 897 u32 name_len;
898 char *start;
899 int ret = 0;
96b5bd77 900 int num = 0;
31db9f7c 901 int index;
96b5bd77
JS		 902 u64 dir;
903 unsigned long name_off;
904 unsigned long elem_size;
905 unsigned long ptr;
31db9f7c 906
924794c9 907 p = fs_path_alloc_reversed();
31db9f7c
AB		 908 if (!p)
909 return -ENOMEM;
910
911 tmp_path = alloc_path_for_send();
912 if (!tmp_path) {
924794c9 913 fs_path_free(p);
31db9f7c
AB		 914 return -ENOMEM;
915 }
916
31db9f7c 917
96b5bd77
JS		 918 if (found_key->type == BTRFS_INODE_REF_KEY) {
919 ptr = (unsigned long)btrfs_item_ptr(eb, slot,
920 struct btrfs_inode_ref);
dd3cc16b 921 item = btrfs_item_nr(slot);
96b5bd77
JS		 922 total = btrfs_item_size(eb, item);
923 elem_size = sizeof(*iref);
924 } else {
925 ptr = btrfs_item_ptr_offset(eb, slot);
926 total = btrfs_item_size_nr(eb, slot);
927 elem_size = sizeof(*extref);
928 }
929
31db9f7c
AB		 930 while (cur < total) {
931 fs_path_reset(p);
932
96b5bd77
JS		 933 if (found_key->type == BTRFS_INODE_REF_KEY) {
934 iref = (struct btrfs_inode_ref *)(ptr + cur);
935 name_len = btrfs_inode_ref_name_len(eb, iref);
936 name_off = (unsigned long)(iref + 1);
937 index = btrfs_inode_ref_index(eb, iref);
938 dir = found_key->offset;
939 } else {
940 extref = (struct btrfs_inode_extref *)(ptr + cur);
941 name_len = btrfs_inode_extref_name_len(eb, extref);
942 name_off = (unsigned long)&extref->name;
943 index = btrfs_inode_extref_index(eb, extref);
944 dir = btrfs_inode_extref_parent(eb, extref);
945 }
946
31db9f7c 947 if (resolve) {
96b5bd77
JS		 948 start = btrfs_ref_to_path(root, tmp_path, name_len,
949 name_off, eb, dir,
950 p->buf, p->buf_len);
31db9f7c
AB		 951 if (IS_ERR(start)) {
952 ret = PTR_ERR(start);
953 goto out;
954 }
955 if (start < p->buf) {
956 /* overflow , try again with larger buffer */
957 ret = fs_path_ensure_buf(p,
958 p->buf_len + p->buf - start);
959 if (ret < 0)
960 goto out;
96b5bd77
JS		 961 start = btrfs_ref_to_path(root, tmp_path,
962 name_len, name_off,
963 eb, dir,
964 p->buf, p->buf_len);
31db9f7c
AB		 965 if (IS_ERR(start)) {
966 ret = PTR_ERR(start);
967 goto out;
968 }
969 BUG_ON(start < p->buf);
970 }
971 p->start = start;
972 } else {
96b5bd77
JS		 973 ret = fs_path_add_from_extent_buffer(p, eb, name_off,
974 name_len);
31db9f7c
AB		 975 if (ret < 0)
976 goto out;
977 }
978
96b5bd77
JS		 979 cur += elem_size + name_len;
980 ret = iterate(num, dir, index, p, ctx);
31db9f7c
AB		 981 if (ret)
982 goto out;
31db9f7c
AB		 983 num++;
984 }
985
986out:
987 btrfs_free_path(tmp_path);
924794c9 988 fs_path_free(p);
31db9f7c
AB		 989 return ret;
990}
991
992typedef int (*iterate_dir_item_t)(int num, struct btrfs_key *di_key,
993 const char *name, int name_len,
994 const char *data, int data_len,
995 u8 type, void *ctx);
996
997/*
998 * Helper function to iterate the entries in ONE btrfs_dir_item.
999 * The iterate callback may return a non zero value to stop iteration. This can
1000 * be a negative value for error codes or 1 to simply stop it.
1001 *
1002 * path must point to the dir item when called.
1003 */
924794c9 1004static int iterate_dir_item(struct btrfs_root *root, struct btrfs_path *path,
31db9f7c
AB		 1005 struct btrfs_key *found_key,
1006 iterate_dir_item_t iterate, void *ctx)
1007{
1008 int ret = 0;
1009 struct extent_buffer *eb;
1010 struct btrfs_item *item;
1011 struct btrfs_dir_item *di;
31db9f7c
AB		 1012 struct btrfs_key di_key;
1013 char *buf = NULL;
7e3ae33e 1014 int buf_len;
31db9f7c
AB		 1015 u32 name_len;
1016 u32 data_len;
1017 u32 cur;
1018 u32 len;
1019 u32 total;
1020 int slot;
1021 int num;
1022 u8 type;
1023
4395e0c4
FM		 1024 /*
1025 * Start with a small buffer (1 page). If later we end up needing more
1026 * space, which can happen for xattrs on a fs with a leaf size greater
1027 * then the page size, attempt to increase the buffer. Typically xattr
1028 * values are small.
1029 */
1030 buf_len = PATH_MAX;
e780b0d1 1031 buf = kmalloc(buf_len, GFP_KERNEL);
31db9f7c
AB		 1032 if (!buf) {
1033 ret = -ENOMEM;
1034 goto out;
1035 }
1036
31db9f7c
AB		 1037 eb = path->nodes[0];
1038 slot = path->slots[0];
dd3cc16b 1039 item = btrfs_item_nr(slot);
31db9f7c
AB		 1040 di = btrfs_item_ptr(eb, slot, struct btrfs_dir_item);
1041 cur = 0;
1042 len = 0;
1043 total = btrfs_item_size(eb, item);
1044
1045 num = 0;
1046 while (cur < total) {
1047 name_len = btrfs_dir_name_len(eb, di);
1048 data_len = btrfs_dir_data_len(eb, di);
1049 type = btrfs_dir_type(eb, di);
1050 btrfs_dir_item_key_to_cpu(eb, di, &di_key);
1051
7e3ae33e
FM		 1052 if (type == BTRFS_FT_XATTR) {
1053 if (name_len > XATTR_NAME_MAX) {
1054 ret = -ENAMETOOLONG;
1055 goto out;
1056 }
da17066c
JM		 1057 if (name_len + data_len >
1058 BTRFS_MAX_XATTR_SIZE(root->fs_info)) {
7e3ae33e
FM		 1059 ret = -E2BIG;
1060 goto out;
1061 }
1062 } else {
1063 /*
1064 * Path too long
1065 */
4395e0c4 1066 if (name_len + data_len > PATH_MAX) {
7e3ae33e
FM		 1067 ret = -ENAMETOOLONG;
1068 goto out;
1069 }
31db9f7c
AB		 1070 }
1071
4395e0c4
FM		 1072 if (name_len + data_len > buf_len) {
1073 buf_len = name_len + data_len;
1074 if (is_vmalloc_addr(buf)) {
1075 vfree(buf);
1076 buf = NULL;
1077 } else {
1078 char *tmp = krealloc(buf, buf_len,
e780b0d1 1079 GFP_KERNEL | __GFP_NOWARN);
4395e0c4
FM		 1080
1081 if (!tmp)
1082 kfree(buf);
1083 buf = tmp;
1084 }
1085 if (!buf) {
1086 buf = vmalloc(buf_len);
1087 if (!buf) {
1088 ret = -ENOMEM;
1089 goto out;
1090 }
1091 }
1092 }
1093
31db9f7c
AB		 1094 read_extent_buffer(eb, buf, (unsigned long)(di + 1),
1095 name_len + data_len);
1096
1097 len = sizeof(*di) + name_len + data_len;
1098 di = (struct btrfs_dir_item *)((char *)di + len);
1099 cur += len;
1100
1101 ret = iterate(num, &di_key, buf, name_len, buf + name_len,
1102 data_len, type, ctx);
1103 if (ret < 0)
1104 goto out;
1105 if (ret) {
1106 ret = 0;
1107 goto out;
1108 }
1109
1110 num++;
1111 }
1112
1113out:
4395e0c4 1114 kvfree(buf);
31db9f7c
AB		 1115 return ret;
1116}
1117
1118static int __copy_first_ref(int num, u64 dir, int index,
1119 struct fs_path *p, void *ctx)
1120{
1121 int ret;
1122 struct fs_path *pt = ctx;
1123
1124 ret = fs_path_copy(pt, p);
1125 if (ret < 0)
1126 return ret;
1127
1128 /* we want the first only */
1129 return 1;
1130}
1131
1132/*
1133 * Retrieve the first path of an inode. If an inode has more then one
1134 * ref/hardlink, this is ignored.
1135 */
924794c9 1136static int get_inode_path(struct btrfs_root *root,
31db9f7c
AB		 1137 u64 ino, struct fs_path *path)
1138{
1139 int ret;
1140 struct btrfs_key key, found_key;
1141 struct btrfs_path *p;
1142
1143 p = alloc_path_for_send();
1144 if (!p)
1145 return -ENOMEM;
1146
1147 fs_path_reset(path);
1148
1149 key.objectid = ino;
1150 key.type = BTRFS_INODE_REF_KEY;
1151 key.offset = 0;
1152
1153 ret = btrfs_search_slot_for_read(root, &key, p, 1, 0);
1154 if (ret < 0)
1155 goto out;
1156 if (ret) {
1157 ret = 1;
1158 goto out;
1159 }
1160 btrfs_item_key_to_cpu(p->nodes[0], &found_key, p->slots[0]);
1161 if (found_key.objectid != ino ||
96b5bd77
JS		 1162 (found_key.type != BTRFS_INODE_REF_KEY &&
1163 found_key.type != BTRFS_INODE_EXTREF_KEY)) {
31db9f7c
AB		 1164 ret = -ENOENT;
1165 goto out;
1166 }
1167
924794c9
TI		 1168 ret = iterate_inode_ref(root, p, &found_key, 1,
1169 __copy_first_ref, path);
31db9f7c
AB		 1170 if (ret < 0)
1171 goto out;
1172 ret = 0;
1173
1174out:
1175 btrfs_free_path(p);
1176 return ret;
1177}
1178
1179struct backref_ctx {
1180 struct send_ctx *sctx;
1181
3f8a18cc 1182 struct btrfs_path *path;
31db9f7c
AB		 1183 /* number of total found references */
1184 u64 found;
1185
1186 /*
1187 * used for clones found in send_root. clones found behind cur_objectid
1188 * and cur_offset are not considered as allowed clones.
1189 */
1190 u64 cur_objectid;
1191 u64 cur_offset;
1192
1193 /* may be truncated in case it's the last extent in a file */
1194 u64 extent_len;
1195
619d8c4e
FM		 1196 /* data offset in the file extent item */
1197 u64 data_offset;
1198
31db9f7c 1199 /* Just to check for bugs in backref resolving */
ee849c04 1200 int found_itself;
31db9f7c
AB		 1201};
1202
1203static int __clone_root_cmp_bsearch(const void *key, const void *elt)
1204{
995e01b7 1205 u64 root = (u64)(uintptr_t)key;
31db9f7c
AB		 1206 struct clone_root *cr = (struct clone_root *)elt;
1207
1208 if (root < cr->root->objectid)
1209 return -1;
1210 if (root > cr->root->objectid)
1211 return 1;
1212 return 0;
1213}
1214
1215static int __clone_root_cmp_sort(const void *e1, const void *e2)
1216{
1217 struct clone_root *cr1 = (struct clone_root *)e1;
1218 struct clone_root *cr2 = (struct clone_root *)e2;
1219
1220 if (cr1->root->objectid < cr2->root->objectid)
1221 return -1;
1222 if (cr1->root->objectid > cr2->root->objectid)
1223 return 1;
1224 return 0;
1225}
1226
1227/*
1228 * Called for every backref that is found for the current extent.
766702ef 1229 * Results are collected in sctx->clone_roots->ino/offset/found_refs
31db9f7c
AB		 1230 */
1231static int __iterate_backrefs(u64 ino, u64 offset, u64 root, void *ctx_)
1232{
1233 struct backref_ctx *bctx = ctx_;
1234 struct clone_root *found;
1235 int ret;
1236 u64 i_size;
1237
1238 /* First check if the root is in the list of accepted clone sources */
995e01b7 1239 found = bsearch((void *)(uintptr_t)root, bctx->sctx->clone_roots,
31db9f7c
AB		 1240 bctx->sctx->clone_roots_cnt,
1241 sizeof(struct clone_root),
1242 __clone_root_cmp_bsearch);
1243 if (!found)
1244 return 0;
1245
1246 if (found->root == bctx->sctx->send_root &&
1247 ino == bctx->cur_objectid &&
1248 offset == bctx->cur_offset) {
ee849c04 1249 bctx->found_itself = 1;
31db9f7c
AB		 1250 }
1251
1252 /*
766702ef 1253 * There are inodes that have extents that lie behind its i_size. Don't
31db9f7c
AB		 1254 * accept clones from these extents.
1255 */
3f8a18cc
JB		 1256 ret = __get_inode_info(found->root, bctx->path, ino, &i_size, NULL, NULL,
1257 NULL, NULL, NULL);
1258 btrfs_release_path(bctx->path);
31db9f7c
AB		 1259 if (ret < 0)
1260 return ret;
1261
619d8c4e 1262 if (offset + bctx->data_offset + bctx->extent_len > i_size)
31db9f7c
AB		 1263 return 0;
1264
1265 /*
1266 * Make sure we don't consider clones from send_root that are
1267 * behind the current inode/offset.
1268 */
1269 if (found->root == bctx->sctx->send_root) {
1270 /*
1271 * TODO for the moment we don't accept clones from the inode
1272 * that is currently send. We may change this when
1273 * BTRFS_IOC_CLONE_RANGE supports cloning from and to the same
1274 * file.
1275 */
1276 if (ino >= bctx->cur_objectid)
1277 return 0;
e938c8ad
AB		 1278#if 0
1279 if (ino > bctx->cur_objectid)
1280 return 0;
1281 if (offset + bctx->extent_len > bctx->cur_offset)
31db9f7c 1282 return 0;
e938c8ad 1283#endif
31db9f7c
AB		 1284 }
1285
1286 bctx->found++;
1287 found->found_refs++;
1288 if (ino < found->ino) {
1289 found->ino = ino;
1290 found->offset = offset;
1291 } else if (found->ino == ino) {
1292 /*
1293 * same extent found more then once in the same file.
1294 */
1295 if (found->offset > offset + bctx->extent_len)
1296 found->offset = offset;
1297 }
1298
1299 return 0;
1300}
1301
1302/*
766702ef
AB		 1303 * Given an inode, offset and extent item, it finds a good clone for a clone
1304 * instruction. Returns -ENOENT when none could be found. The function makes
1305 * sure that the returned clone is usable at the point where sending is at the
1306 * moment. This means, that no clones are accepted which lie behind the current
1307 * inode+offset.
1308 *
31db9f7c
AB		 1309 * path must point to the extent item when called.
1310 */
1311static int find_extent_clone(struct send_ctx *sctx,
1312 struct btrfs_path *path,
1313 u64 ino, u64 data_offset,
1314 u64 ino_size,
1315 struct clone_root **found)
1316{
04ab956e 1317 struct btrfs_fs_info *fs_info = sctx->send_root->fs_info;
31db9f7c
AB		 1318 int ret;
1319 int extent_type;
1320 u64 logical;
74dd17fb 1321 u64 disk_byte;
31db9f7c
AB		 1322 u64 num_bytes;
1323 u64 extent_item_pos;
69917e43 1324 u64 flags = 0;
31db9f7c
AB		 1325 struct btrfs_file_extent_item *fi;
1326 struct extent_buffer *eb = path->nodes[0];
35075bb0 1327 struct backref_ctx *backref_ctx = NULL;
31db9f7c
AB		 1328 struct clone_root *cur_clone_root;
1329 struct btrfs_key found_key;
1330 struct btrfs_path *tmp_path;
74dd17fb 1331 int compressed;
31db9f7c
AB		 1332 u32 i;
1333
1334 tmp_path = alloc_path_for_send();
1335 if (!tmp_path)
1336 return -ENOMEM;
1337
3f8a18cc
JB		 1338 /* We only use this path under the commit sem */
1339 tmp_path->need_commit_sem = 0;
1340
e780b0d1 1341 backref_ctx = kmalloc(sizeof(*backref_ctx), GFP_KERNEL);
35075bb0
AB		 1342 if (!backref_ctx) {
1343 ret = -ENOMEM;
1344 goto out;
1345 }
1346
3f8a18cc
JB		 1347 backref_ctx->path = tmp_path;
1348
31db9f7c
AB		 1349 if (data_offset >= ino_size) {
1350 /*
1351 * There may be extents that lie behind the file's size.
1352 * I at least had this in combination with snapshotting while
1353 * writing large files.
1354 */
1355 ret = 0;
1356 goto out;
1357 }
1358
1359 fi = btrfs_item_ptr(eb, path->slots[0],
1360 struct btrfs_file_extent_item);
1361 extent_type = btrfs_file_extent_type(eb, fi);
1362 if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
1363 ret = -ENOENT;
1364 goto out;
1365 }
74dd17fb 1366 compressed = btrfs_file_extent_compression(eb, fi);
31db9f7c
AB		 1367
1368 num_bytes = btrfs_file_extent_num_bytes(eb, fi);
74dd17fb
CM		 1369 disk_byte = btrfs_file_extent_disk_bytenr(eb, fi);
1370 if (disk_byte == 0) {
31db9f7c
AB		 1371 ret = -ENOENT;
1372 goto out;
1373 }
74dd17fb 1374 logical = disk_byte + btrfs_file_extent_offset(eb, fi);
31db9f7c 1375
04ab956e
JM		 1376 down_read(&fs_info->commit_root_sem);
1377 ret = extent_from_logical(fs_info, disk_byte, tmp_path,
69917e43 1378 &found_key, &flags);
04ab956e 1379 up_read(&fs_info->commit_root_sem);
31db9f7c
AB		 1380 btrfs_release_path(tmp_path);
1381
1382 if (ret < 0)
1383 goto out;
69917e43 1384 if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
31db9f7c
AB		 1385 ret = -EIO;
1386 goto out;
1387 }
1388
1389 /*
1390 * Setup the clone roots.
1391 */
1392 for (i = 0; i < sctx->clone_roots_cnt; i++) {
1393 cur_clone_root = sctx->clone_roots + i;
1394 cur_clone_root->ino = (u64)-1;
1395 cur_clone_root->offset = 0;
1396 cur_clone_root->found_refs = 0;
1397 }
1398
35075bb0
AB		 1399 backref_ctx->sctx = sctx;
1400 backref_ctx->found = 0;
1401 backref_ctx->cur_objectid = ino;
1402 backref_ctx->cur_offset = data_offset;
1403 backref_ctx->found_itself = 0;
1404 backref_ctx->extent_len = num_bytes;
619d8c4e
FM		 1405 /*
1406 * For non-compressed extents iterate_extent_inodes() gives us extent
1407 * offsets that already take into account the data offset, but not for
1408 * compressed extents, since the offset is logical and not relative to
1409 * the physical extent locations. We must take this into account to
1410 * avoid sending clone offsets that go beyond the source file's size,
1411 * which would result in the clone ioctl failing with -EINVAL on the
1412 * receiving end.
1413 */
1414 if (compressed == BTRFS_COMPRESS_NONE)
1415 backref_ctx->data_offset = 0;
1416 else
1417 backref_ctx->data_offset = btrfs_file_extent_offset(eb, fi);
31db9f7c
AB		 1418
1419 /*
1420 * The last extent of a file may be too large due to page alignment.
1421 * We need to adjust extent_len in this case so that the checks in
1422 * __iterate_backrefs work.
1423 */
1424 if (data_offset + num_bytes >= ino_size)
35075bb0 1425 backref_ctx->extent_len = ino_size - data_offset;
31db9f7c
AB		 1426
1427 /*
1428 * Now collect all backrefs.
1429 */
74dd17fb
CM		 1430 if (compressed == BTRFS_COMPRESS_NONE)
1431 extent_item_pos = logical - found_key.objectid;
1432 else
1433 extent_item_pos = 0;
0b246afa
JM		 1434 ret = iterate_extent_inodes(fs_info, found_key.objectid,
1435 extent_item_pos, 1, __iterate_backrefs,
1436 backref_ctx);
74dd17fb 1437
31db9f7c
AB		 1438 if (ret < 0)
1439 goto out;
1440
35075bb0 1441 if (!backref_ctx->found_itself) {
31db9f7c
AB		 1442 /* found a bug in backref code? */
1443 ret = -EIO;
04ab956e 1444 btrfs_err(fs_info,
5d163e0e 1445 "did not find backref in send_root. inode=%llu, offset=%llu, disk_byte=%llu found extent=%llu",
04ab956e 1446 ino, data_offset, disk_byte, found_key.objectid);
31db9f7c
AB		 1447 goto out;
1448 }
1449
04ab956e
JM		 1450 btrfs_debug(fs_info,
1451 "find_extent_clone: data_offset=%llu, ino=%llu, num_bytes=%llu, logical=%llu",
1452 data_offset, ino, num_bytes, logical);
31db9f7c 1453
35075bb0 1454 if (!backref_ctx->found)
04ab956e 1455 btrfs_debug(fs_info, "no clones found");
31db9f7c
AB		 1456
1457 cur_clone_root = NULL;
1458 for (i = 0; i < sctx->clone_roots_cnt; i++) {
1459 if (sctx->clone_roots[i].found_refs) {
1460 if (!cur_clone_root)
1461 cur_clone_root = sctx->clone_roots + i;
1462 else if (sctx->clone_roots[i].root == sctx->send_root)
1463 /* prefer clones from send_root over others */
1464 cur_clone_root = sctx->clone_roots + i;
31db9f7c
AB		 1465 }
1466
1467 }
1468
1469 if (cur_clone_root) {
1470 *found = cur_clone_root;
1471 ret = 0;
1472 } else {
1473 ret = -ENOENT;
1474 }
1475
1476out:
1477 btrfs_free_path(tmp_path);
35075bb0 1478 kfree(backref_ctx);
31db9f7c
AB		 1479 return ret;
1480}
1481
924794c9 1482static int read_symlink(struct btrfs_root *root,
31db9f7c
AB		 1483 u64 ino,
1484 struct fs_path *dest)
1485{
1486 int ret;
1487 struct btrfs_path *path;
1488 struct btrfs_key key;
1489 struct btrfs_file_extent_item *ei;
1490 u8 type;
1491 u8 compression;
1492 unsigned long off;
1493 int len;
1494
1495 path = alloc_path_for_send();
1496 if (!path)
1497 return -ENOMEM;
1498
1499 key.objectid = ino;
1500 key.type = BTRFS_EXTENT_DATA_KEY;
1501 key.offset = 0;
1502 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1503 if (ret < 0)
1504 goto out;
a879719b
FM		 1505 if (ret) {
1506 /*
1507 * An empty symlink inode. Can happen in rare error paths when
1508 * creating a symlink (transaction committed before the inode
1509 * eviction handler removed the symlink inode items and a crash
1510 * happened in between or the subvol was snapshoted in between).
1511 * Print an informative message to dmesg/syslog so that the user
1512 * can delete the symlink.
1513 */
1514 btrfs_err(root->fs_info,
1515 "Found empty symlink inode %llu at root %llu",
1516 ino, root->root_key.objectid);
1517 ret = -EIO;
1518 goto out;
1519 }
31db9f7c
AB		 1520
1521 ei = btrfs_item_ptr(path->nodes[0], path->slots[0],
1522 struct btrfs_file_extent_item);
1523 type = btrfs_file_extent_type(path->nodes[0], ei);
1524 compression = btrfs_file_extent_compression(path->nodes[0], ei);
1525 BUG_ON(type != BTRFS_FILE_EXTENT_INLINE);
1526 BUG_ON(compression);
1527
1528 off = btrfs_file_extent_inline_start(ei);
514ac8ad 1529 len = btrfs_file_extent_inline_len(path->nodes[0], path->slots[0], ei);
31db9f7c
AB		 1530
1531 ret = fs_path_add_from_extent_buffer(dest, path->nodes[0], off, len);
31db9f7c
AB		 1532
1533out:
1534 btrfs_free_path(path);
1535 return ret;
1536}
1537
1538/*
1539 * Helper function to generate a file name that is unique in the root of
1540 * send_root and parent_root. This is used to generate names for orphan inodes.
1541 */
1542static int gen_unique_name(struct send_ctx *sctx,
1543 u64 ino, u64 gen,
1544 struct fs_path *dest)
1545{
1546 int ret = 0;
1547 struct btrfs_path *path;
1548 struct btrfs_dir_item *di;
1549 char tmp[64];
1550 int len;
1551 u64 idx = 0;
1552
1553 path = alloc_path_for_send();
1554 if (!path)
1555 return -ENOMEM;
1556
1557 while (1) {
f74b86d8 1558 len = snprintf(tmp, sizeof(tmp), "o%llu-%llu-%llu",
31db9f7c 1559 ino, gen, idx);
64792f25 1560 ASSERT(len < sizeof(tmp));
31db9f7c
AB		 1561
1562 di = btrfs_lookup_dir_item(NULL, sctx->send_root,
1563 path, BTRFS_FIRST_FREE_OBJECTID,
1564 tmp, strlen(tmp), 0);
1565 btrfs_release_path(path);
1566 if (IS_ERR(di)) {
1567 ret = PTR_ERR(di);
1568 goto out;
1569 }
1570 if (di) {
1571 /* not unique, try again */
1572 idx++;
1573 continue;
1574 }
1575
1576 if (!sctx->parent_root) {
1577 /* unique */
1578 ret = 0;
1579 break;
1580 }
1581
1582 di = btrfs_lookup_dir_item(NULL, sctx->parent_root,
1583 path, BTRFS_FIRST_FREE_OBJECTID,
1584 tmp, strlen(tmp), 0);
1585 btrfs_release_path(path);
1586 if (IS_ERR(di)) {
1587 ret = PTR_ERR(di);
1588 goto out;
1589 }
1590 if (di) {
1591 /* not unique, try again */
1592 idx++;
1593 continue;
1594 }
1595 /* unique */
1596 break;
1597 }
1598
1599 ret = fs_path_add(dest, tmp, strlen(tmp));
1600
1601out:
1602 btrfs_free_path(path);
1603 return ret;
1604}
1605
1606enum inode_state {
1607 inode_state_no_change,
1608 inode_state_will_create,
1609 inode_state_did_create,
1610 inode_state_will_delete,
1611 inode_state_did_delete,
1612};
1613
1614static int get_cur_inode_state(struct send_ctx *sctx, u64 ino, u64 gen)
1615{
1616 int ret;
1617 int left_ret;
1618 int right_ret;
1619 u64 left_gen;
1620 u64 right_gen;
1621
1622 ret = get_inode_info(sctx->send_root, ino, NULL, &left_gen, NULL, NULL,
85a7b33b 1623 NULL, NULL);
31db9f7c
AB		 1624 if (ret < 0 && ret != -ENOENT)
1625 goto out;
1626 left_ret = ret;
1627
1628 if (!sctx->parent_root) {
1629 right_ret = -ENOENT;
1630 } else {
1631 ret = get_inode_info(sctx->parent_root, ino, NULL, &right_gen,
85a7b33b 1632 NULL, NULL, NULL, NULL);
31db9f7c
AB		 1633 if (ret < 0 && ret != -ENOENT)
1634 goto out;
1635 right_ret = ret;
1636 }
1637
1638 if (!left_ret && !right_ret) {
e938c8ad 1639 if (left_gen == gen && right_gen == gen) {
31db9f7c 1640 ret = inode_state_no_change;
e938c8ad 1641 } else if (left_gen == gen) {
31db9f7c
AB		 1642 if (ino < sctx->send_progress)
1643 ret = inode_state_did_create;
1644 else
1645 ret = inode_state_will_create;
1646 } else if (right_gen == gen) {
1647 if (ino < sctx->send_progress)
1648 ret = inode_state_did_delete;
1649 else
1650 ret = inode_state_will_delete;
1651 } else {
1652 ret = -ENOENT;
1653 }
1654 } else if (!left_ret) {
1655 if (left_gen == gen) {
1656 if (ino < sctx->send_progress)
1657 ret = inode_state_did_create;
1658 else
1659 ret = inode_state_will_create;
1660 } else {
1661 ret = -ENOENT;
1662 }
1663 } else if (!right_ret) {
1664 if (right_gen == gen) {
1665 if (ino < sctx->send_progress)
1666 ret = inode_state_did_delete;
1667 else
1668 ret = inode_state_will_delete;
1669 } else {
1670 ret = -ENOENT;
1671 }
1672 } else {
1673 ret = -ENOENT;
1674 }
1675
1676out:
1677 return ret;
1678}
1679
1680static int is_inode_existent(struct send_ctx *sctx, u64 ino, u64 gen)
1681{
1682 int ret;
1683
4dd9920d
RK		 1684 if (ino == BTRFS_FIRST_FREE_OBJECTID)
1685 return 1;
1686
31db9f7c
AB		 1687 ret = get_cur_inode_state(sctx, ino, gen);
1688 if (ret < 0)
1689 goto out;
1690
1691 if (ret == inode_state_no_change ||
1692 ret == inode_state_did_create ||
1693 ret == inode_state_will_delete)
1694 ret = 1;
1695 else
1696 ret = 0;
1697
1698out:
1699 return ret;
1700}
1701
1702/*
1703 * Helper function to lookup a dir item in a dir.
1704 */
1705static int lookup_dir_item_inode(struct btrfs_root *root,
1706 u64 dir, const char *name, int name_len,
1707 u64 *found_inode,
1708 u8 *found_type)
1709{
1710 int ret = 0;
1711 struct btrfs_dir_item *di;
1712 struct btrfs_key key;
1713 struct btrfs_path *path;
1714
1715 path = alloc_path_for_send();
1716 if (!path)
1717 return -ENOMEM;
1718
1719 di = btrfs_lookup_dir_item(NULL, root, path,
1720 dir, name, name_len, 0);
1721 if (!di) {
1722 ret = -ENOENT;
1723 goto out;
1724 }
1725 if (IS_ERR(di)) {
1726 ret = PTR_ERR(di);
1727 goto out;
1728 }
1729 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key);
1af56070
FM		 1730 if (key.type == BTRFS_ROOT_ITEM_KEY) {
1731 ret = -ENOENT;
1732 goto out;
1733 }
31db9f7c
AB		 1734 *found_inode = key.objectid;
1735 *found_type = btrfs_dir_type(path->nodes[0], di);
1736
1737out:
1738 btrfs_free_path(path);
1739 return ret;
1740}
1741
766702ef
AB		 1742/*
1743 * Looks up the first btrfs_inode_ref of a given ino. It returns the parent dir,
1744 * generation of the parent dir and the name of the dir entry.
1745 */
924794c9 1746static int get_first_ref(struct btrfs_root *root, u64 ino,
31db9f7c
AB		 1747 u64 *dir, u64 *dir_gen, struct fs_path *name)
1748{
1749 int ret;
1750 struct btrfs_key key;
1751 struct btrfs_key found_key;
1752 struct btrfs_path *path;
31db9f7c 1753 int len;
96b5bd77 1754 u64 parent_dir;
31db9f7c
AB		 1755
1756 path = alloc_path_for_send();
1757 if (!path)
1758 return -ENOMEM;
1759
1760 key.objectid = ino;
1761 key.type = BTRFS_INODE_REF_KEY;
1762 key.offset = 0;
1763
1764 ret = btrfs_search_slot_for_read(root, &key, path, 1, 0);
1765 if (ret < 0)
1766 goto out;
1767 if (!ret)
1768 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1769 path->slots[0]);
96b5bd77
JS		 1770 if (ret || found_key.objectid != ino ||
1771 (found_key.type != BTRFS_INODE_REF_KEY &&
1772 found_key.type != BTRFS_INODE_EXTREF_KEY)) {
31db9f7c
AB		 1773 ret = -ENOENT;
1774 goto out;
1775 }
1776
51a60253 1777 if (found_key.type == BTRFS_INODE_REF_KEY) {
96b5bd77
JS		 1778 struct btrfs_inode_ref *iref;
1779 iref = btrfs_item_ptr(path->nodes[0], path->slots[0],
1780 struct btrfs_inode_ref);
1781 len = btrfs_inode_ref_name_len(path->nodes[0], iref);
1782 ret = fs_path_add_from_extent_buffer(name, path->nodes[0],
1783 (unsigned long)(iref + 1),
1784 len);
1785 parent_dir = found_key.offset;
1786 } else {
1787 struct btrfs_inode_extref *extref;
1788 extref = btrfs_item_ptr(path->nodes[0], path->slots[0],
1789 struct btrfs_inode_extref);
1790 len = btrfs_inode_extref_name_len(path->nodes[0], extref);
1791 ret = fs_path_add_from_extent_buffer(name, path->nodes[0],
1792 (unsigned long)&extref->name, len);
1793 parent_dir = btrfs_inode_extref_parent(path->nodes[0], extref);
1794 }
31db9f7c
AB		 1795 if (ret < 0)
1796 goto out;
1797 btrfs_release_path(path);
1798
b46ab97b
FM		 1799 if (dir_gen) {
1800 ret = get_inode_info(root, parent_dir, NULL, dir_gen, NULL,
1801 NULL, NULL, NULL);
1802 if (ret < 0)
1803 goto out;
1804 }
31db9f7c 1805
96b5bd77 1806 *dir = parent_dir;
31db9f7c
AB		 1807
1808out:
1809 btrfs_free_path(path);
1810 return ret;
1811}
1812
924794c9 1813static int is_first_ref(struct btrfs_root *root,
31db9f7c
AB		 1814 u64 ino, u64 dir,
1815 const char *name, int name_len)
1816{
1817 int ret;
1818 struct fs_path *tmp_name;
1819 u64 tmp_dir;
31db9f7c 1820
924794c9 1821 tmp_name = fs_path_alloc();
31db9f7c
AB		 1822 if (!tmp_name)
1823 return -ENOMEM;
1824
b46ab97b 1825 ret = get_first_ref(root, ino, &tmp_dir, NULL, tmp_name);
31db9f7c
AB		 1826 if (ret < 0)
1827 goto out;
1828
b9291aff 1829 if (dir != tmp_dir || name_len != fs_path_len(tmp_name)) {
31db9f7c
AB		 1830 ret = 0;
1831 goto out;
1832 }
1833
e938c8ad 1834 ret = !memcmp(tmp_name->start, name, name_len);
31db9f7c
AB		 1835
1836out:
924794c9 1837 fs_path_free(tmp_name);
31db9f7c
AB		 1838 return ret;
1839}
1840
766702ef
AB		 1841/*
1842 * Used by process_recorded_refs to determine if a new ref would overwrite an
1843 * already existing ref. In case it detects an overwrite, it returns the
1844 * inode/gen in who_ino/who_gen.
1845 * When an overwrite is detected, process_recorded_refs does proper orphanizing
1846 * to make sure later references to the overwritten inode are possible.
1847 * Orphanizing is however only required for the first ref of an inode.
1848 * process_recorded_refs does an additional is_first_ref check to see if
1849 * orphanizing is really required.
1850 */
31db9f7c
AB		 1851static int will_overwrite_ref(struct send_ctx *sctx, u64 dir, u64 dir_gen,
1852 const char *name, int name_len,
1853 u64 *who_ino, u64 *who_gen)
1854{
1855 int ret = 0;
ebdad913 1856 u64 gen;
31db9f7c
AB		 1857 u64 other_inode = 0;
1858 u8 other_type = 0;
1859
1860 if (!sctx->parent_root)
1861 goto out;
1862
1863 ret = is_inode_existent(sctx, dir, dir_gen);
1864 if (ret <= 0)
1865 goto out;
1866
ebdad913
JB		 1867 /*
1868 * If we have a parent root we need to verify that the parent dir was
01327610 1869 * not deleted and then re-created, if it was then we have no overwrite
ebdad913
JB		 1870 * and we can just unlink this entry.
1871 */
4dd9920d 1872 if (sctx->parent_root && dir != BTRFS_FIRST_FREE_OBJECTID) {
ebdad913
JB		 1873 ret = get_inode_info(sctx->parent_root, dir, NULL, &gen, NULL,
1874 NULL, NULL, NULL);
1875 if (ret < 0 && ret != -ENOENT)
1876 goto out;
1877 if (ret) {
1878 ret = 0;
1879 goto out;
1880 }
1881 if (gen != dir_gen)
1882 goto out;
1883 }
1884
31db9f7c
AB		 1885 ret = lookup_dir_item_inode(sctx->parent_root, dir, name, name_len,
1886 &other_inode, &other_type);
1887 if (ret < 0 && ret != -ENOENT)
1888 goto out;
1889 if (ret) {
1890 ret = 0;
1891 goto out;
1892 }
1893
766702ef
AB		 1894 /*
1895 * Check if the overwritten ref was already processed. If yes, the ref
1896 * was already unlinked/moved, so we can safely assume that we will not
1897 * overwrite anything at this point in time.
1898 */
801bec36
RK		 1899 if (other_inode > sctx->send_progress ||
1900 is_waiting_for_move(sctx, other_inode)) {
31db9f7c 1901 ret = get_inode_info(sctx->parent_root, other_inode, NULL,
85a7b33b 1902 who_gen, NULL, NULL, NULL, NULL);
31db9f7c
AB		 1903 if (ret < 0)
1904 goto out;
1905
1906 ret = 1;
1907 *who_ino = other_inode;
1908 } else {
1909 ret = 0;
1910 }
1911
1912out:
1913 return ret;
1914}
1915
766702ef
AB		 1916/*
1917 * Checks if the ref was overwritten by an already processed inode. This is
1918 * used by __get_cur_name_and_parent to find out if the ref was orphanized and
1919 * thus the orphan name needs be used.
1920 * process_recorded_refs also uses it to avoid unlinking of refs that were
1921 * overwritten.
1922 */
31db9f7c
AB		 1923static int did_overwrite_ref(struct send_ctx *sctx,
1924 u64 dir, u64 dir_gen,
1925 u64 ino, u64 ino_gen,
1926 const char *name, int name_len)
1927{
1928 int ret = 0;
1929 u64 gen;
1930 u64 ow_inode;
1931 u8 other_type;
1932
1933 if (!sctx->parent_root)
1934 goto out;
1935
1936 ret = is_inode_existent(sctx, dir, dir_gen);
1937 if (ret <= 0)
1938 goto out;
1939
01914101
RK		 1940 if (dir != BTRFS_FIRST_FREE_OBJECTID) {
1941 ret = get_inode_info(sctx->send_root, dir, NULL, &gen, NULL,
1942 NULL, NULL, NULL);
1943 if (ret < 0 && ret != -ENOENT)
1944 goto out;
1945 if (ret) {
1946 ret = 0;
1947 goto out;
1948 }
1949 if (gen != dir_gen)
1950 goto out;
1951 }
1952
31db9f7c
AB		 1953 /* check if the ref was overwritten by another ref */
1954 ret = lookup_dir_item_inode(sctx->send_root, dir, name, name_len,
1955 &ow_inode, &other_type);
1956 if (ret < 0 && ret != -ENOENT)
1957 goto out;
1958 if (ret) {
1959 /* was never and will never be overwritten */
1960 ret = 0;
1961 goto out;
1962 }
1963
1964 ret = get_inode_info(sctx->send_root, ow_inode, NULL, &gen, NULL, NULL,
85a7b33b 1965 NULL, NULL);
31db9f7c
AB		 1966 if (ret < 0)
1967 goto out;
1968
1969 if (ow_inode == ino && gen == ino_gen) {
1970 ret = 0;
1971 goto out;
1972 }
1973
8b191a68
FM		 1974 /*
1975 * We know that it is or will be overwritten. Check this now.
1976 * The current inode being processed might have been the one that caused
b786f16a
FM		 1977 * inode 'ino' to be orphanized, therefore check if ow_inode matches
1978 * the current inode being processed.
8b191a68 1979 */
b786f16a
FM		 1980 if ((ow_inode < sctx->send_progress) ||
1981 (ino != sctx->cur_ino && ow_inode == sctx->cur_ino &&
1982 gen == sctx->cur_inode_gen))
31db9f7c
AB		 1983 ret = 1;
1984 else
1985 ret = 0;
1986
1987out:
1988 return ret;
1989}
1990
766702ef
AB		 1991/*
1992 * Same as did_overwrite_ref, but also checks if it is the first ref of an inode
1993 * that got overwritten. This is used by process_recorded_refs to determine
1994 * if it has to use the path as returned by get_cur_path or the orphan name.
1995 */
31db9f7c
AB		 1996static int did_overwrite_first_ref(struct send_ctx *sctx, u64 ino, u64 gen)
1997{
1998 int ret = 0;
1999 struct fs_path *name = NULL;
2000 u64 dir;
2001 u64 dir_gen;
2002
2003 if (!sctx->parent_root)
2004 goto out;
2005
924794c9 2006 name = fs_path_alloc();
31db9f7c
AB		 2007 if (!name)
2008 return -ENOMEM;
2009
924794c9 2010 ret = get_first_ref(sctx->parent_root, ino, &dir, &dir_gen, name);
31db9f7c
AB		 2011 if (ret < 0)
2012 goto out;
2013
2014 ret = did_overwrite_ref(sctx, dir, dir_gen, ino, gen,
2015 name->start, fs_path_len(name));
31db9f7c
AB		 2016
2017out:
924794c9 2018 fs_path_free(name);
31db9f7c
AB		 2019 return ret;
2020}
2021
766702ef
AB		 2022/*
2023 * Insert a name cache entry. On 32bit kernels the radix tree index is 32bit,
2024 * so we need to do some special handling in case we have clashes. This function
2025 * takes care of this with the help of name_cache_entry::radix_list.
5dc67d0b 2026 * In case of error, nce is kfreed.
766702ef 2027 */
31db9f7c
AB		 2028static int name_cache_insert(struct send_ctx *sctx,
2029 struct name_cache_entry *nce)
2030{
2031 int ret = 0;
7e0926fe
AB		 2032 struct list_head *nce_head;
2033
2034 nce_head = radix_tree_lookup(&sctx->name_cache,
2035 (unsigned long)nce->ino);
2036 if (!nce_head) {
e780b0d1 2037 nce_head = kmalloc(sizeof(*nce_head), GFP_KERNEL);
cfa7a9cc
TI		 2038 if (!nce_head) {
2039 kfree(nce);
31db9f7c 2040 return -ENOMEM;
cfa7a9cc 2041 }
7e0926fe 2042 INIT_LIST_HEAD(nce_head);
31db9f7c 2043
7e0926fe 2044 ret = radix_tree_insert(&sctx->name_cache, nce->ino, nce_head);
5dc67d0b
AB		 2045 if (ret < 0) {
2046 kfree(nce_head);
2047 kfree(nce);
31db9f7c 2048 return ret;
5dc67d0b 2049 }
31db9f7c 2050 }
7e0926fe 2051 list_add_tail(&nce->radix_list, nce_head);
31db9f7c
AB		 2052 list_add_tail(&nce->list, &sctx->name_cache_list);
2053 sctx->name_cache_size++;
2054
2055 return ret;
2056}
2057
2058static void name_cache_delete(struct send_ctx *sctx,
2059 struct name_cache_entry *nce)
2060{
7e0926fe 2061 struct list_head *nce_head;
31db9f7c 2062
7e0926fe
AB		 2063 nce_head = radix_tree_lookup(&sctx->name_cache,
2064 (unsigned long)nce->ino);
57fb8910
DS		 2065 if (!nce_head) {
2066 btrfs_err(sctx->send_root->fs_info,
2067 "name_cache_delete lookup failed ino %llu cache size %d, leaking memory",
2068 nce->ino, sctx->name_cache_size);
2069 }
31db9f7c 2070
7e0926fe 2071 list_del(&nce->radix_list);
31db9f7c 2072 list_del(&nce->list);
31db9f7c 2073 sctx->name_cache_size--;
7e0926fe 2074
57fb8910
DS		 2075 /*
2076 * We may not get to the final release of nce_head if the lookup fails
2077 */
2078 if (nce_head && list_empty(nce_head)) {
7e0926fe
AB		 2079 radix_tree_delete(&sctx->name_cache, (unsigned long)nce->ino);
2080 kfree(nce_head);
2081 }
31db9f7c
AB		 2082}
2083
2084static struct name_cache_entry *name_cache_search(struct send_ctx *sctx,
2085 u64 ino, u64 gen)
2086{
7e0926fe
AB		 2087 struct list_head *nce_head;
2088 struct name_cache_entry *cur;
31db9f7c 2089
7e0926fe
AB		 2090 nce_head = radix_tree_lookup(&sctx->name_cache, (unsigned long)ino);
2091 if (!nce_head)
31db9f7c
AB		 2092 return NULL;
2093
7e0926fe
AB		 2094 list_for_each_entry(cur, nce_head, radix_list) {
2095 if (cur->ino == ino && cur->gen == gen)
2096 return cur;
2097 }
31db9f7c
AB		 2098 return NULL;
2099}
2100
766702ef
AB		 2101/*
2102 * Removes the entry from the list and adds it back to the end. This marks the
2103 * entry as recently used so that name_cache_clean_unused does not remove it.
2104 */
31db9f7c
AB		 2105static void name_cache_used(struct send_ctx *sctx, struct name_cache_entry *nce)
2106{
2107 list_del(&nce->list);
2108 list_add_tail(&nce->list, &sctx->name_cache_list);
2109}
2110
766702ef
AB		 2111/*
2112 * Remove some entries from the beginning of name_cache_list.
2113 */
31db9f7c
AB		 2114static void name_cache_clean_unused(struct send_ctx *sctx)
2115{
2116 struct name_cache_entry *nce;
2117
2118 if (sctx->name_cache_size < SEND_CTX_NAME_CACHE_CLEAN_SIZE)
2119 return;
2120
2121 while (sctx->name_cache_size > SEND_CTX_MAX_NAME_CACHE_SIZE) {
2122 nce = list_entry(sctx->name_cache_list.next,
2123 struct name_cache_entry, list);
2124 name_cache_delete(sctx, nce);
2125 kfree(nce);
2126 }
2127}
2128
2129static void name_cache_free(struct send_ctx *sctx)
2130{
2131 struct name_cache_entry *nce;
31db9f7c 2132
e938c8ad
AB		 2133 while (!list_empty(&sctx->name_cache_list)) {
2134 nce = list_entry(sctx->name_cache_list.next,
2135 struct name_cache_entry, list);
31db9f7c 2136 name_cache_delete(sctx, nce);
17589bd9 2137 kfree(nce);
31db9f7c
AB		 2138 }
2139}
2140
766702ef
AB		 2141/*
2142 * Used by get_cur_path for each ref up to the root.
2143 * Returns 0 if it succeeded.
2144 * Returns 1 if the inode is not existent or got overwritten. In that case, the
2145 * name is an orphan name. This instructs get_cur_path to stop iterating. If 1
2146 * is returned, parent_ino/parent_gen are not guaranteed to be valid.
2147 * Returns <0 in case of error.
2148 */
31db9f7c
AB		 2149static int __get_cur_name_and_parent(struct send_ctx *sctx,
2150 u64 ino, u64 gen,
2151 u64 *parent_ino,
2152 u64 *parent_gen,
2153 struct fs_path *dest)
2154{
2155 int ret;
2156 int nce_ret;
31db9f7c
AB		 2157 struct name_cache_entry *nce = NULL;
2158
766702ef
AB		 2159 /*
2160 * First check if we already did a call to this function with the same
2161 * ino/gen. If yes, check if the cache entry is still up-to-date. If yes
2162 * return the cached result.
2163 */
31db9f7c
AB		 2164 nce = name_cache_search(sctx, ino, gen);
2165 if (nce) {
2166 if (ino < sctx->send_progress && nce->need_later_update) {
2167 name_cache_delete(sctx, nce);
2168 kfree(nce);
2169 nce = NULL;
2170 } else {
2171 name_cache_used(sctx, nce);
2172 *parent_ino = nce->parent_ino;
2173 *parent_gen = nce->parent_gen;
2174 ret = fs_path_add(dest, nce->name, nce->name_len);
2175 if (ret < 0)
2176 goto out;
2177 ret = nce->ret;
2178 goto out;
2179 }
2180 }
2181
766702ef
AB		 2182 /*
2183 * If the inode is not existent yet, add the orphan name and return 1.
2184 * This should only happen for the parent dir that we determine in
2185 * __record_new_ref
2186 */
31db9f7c
AB		 2187 ret = is_inode_existent(sctx, ino, gen);
2188 if (ret < 0)
2189 goto out;
2190
2191 if (!ret) {
2192 ret = gen_unique_name(sctx, ino, gen, dest);
2193 if (ret < 0)
2194 goto out;
2195 ret = 1;
2196 goto out_cache;
2197 }
2198
766702ef
AB		 2199 /*
2200 * Depending on whether the inode was already processed or not, use
2201 * send_root or parent_root for ref lookup.
2202 */
bf0d1f44 2203 if (ino < sctx->send_progress)
924794c9
TI		 2204 ret = get_first_ref(sctx->send_root, ino,
2205 parent_ino, parent_gen, dest);
31db9f7c 2206 else
924794c9
TI		 2207 ret = get_first_ref(sctx->parent_root, ino,
2208 parent_ino, parent_gen, dest);
31db9f7c
AB		 2209 if (ret < 0)
2210 goto out;
2211
766702ef
AB		 2212 /*
2213 * Check if the ref was overwritten by an inode's ref that was processed
2214 * earlier. If yes, treat as orphan and return 1.
2215 */
31db9f7c
AB		 2216 ret = did_overwrite_ref(sctx, *parent_ino, *parent_gen, ino, gen,
2217 dest->start, dest->end - dest->start);
2218 if (ret < 0)
2219 goto out;
2220 if (ret) {
2221 fs_path_reset(dest);
2222 ret = gen_unique_name(sctx, ino, gen, dest);
2223 if (ret < 0)
2224 goto out;
2225 ret = 1;
2226 }
2227
2228out_cache:
766702ef
AB		 2229 /*
2230 * Store the result of the lookup in the name cache.
2231 */
e780b0d1 2232 nce = kmalloc(sizeof(*nce) + fs_path_len(dest) + 1, GFP_KERNEL);
31db9f7c
AB		 2233 if (!nce) {
2234 ret = -ENOMEM;
2235 goto out;
2236 }
2237
2238 nce->ino = ino;
2239 nce->gen = gen;
2240 nce->parent_ino = *parent_ino;
2241 nce->parent_gen = *parent_gen;
2242 nce->name_len = fs_path_len(dest);
2243 nce->ret = ret;
2244 strcpy(nce->name, dest->start);
31db9f7c
AB		 2245
2246 if (ino < sctx->send_progress)
2247 nce->need_later_update = 0;
2248 else
2249 nce->need_later_update = 1;
2250
2251 nce_ret = name_cache_insert(sctx, nce);
2252 if (nce_ret < 0)
2253 ret = nce_ret;
2254 name_cache_clean_unused(sctx);
2255
2256out:
31db9f7c
AB		 2257 return ret;
2258}
2259
2260/*
2261 * Magic happens here. This function returns the first ref to an inode as it
2262 * would look like while receiving the stream at this point in time.
2263 * We walk the path up to the root. For every inode in between, we check if it
2264 * was already processed/sent. If yes, we continue with the parent as found
2265 * in send_root. If not, we continue with the parent as found in parent_root.
2266 * If we encounter an inode that was deleted at this point in time, we use the
2267 * inodes "orphan" name instead of the real name and stop. Same with new inodes
2268 * that were not created yet and overwritten inodes/refs.
2269 *
2270 * When do we have have orphan inodes:
2271 * 1. When an inode is freshly created and thus no valid refs are available yet
2272 * 2. When a directory lost all it's refs (deleted) but still has dir items
2273 * inside which were not processed yet (pending for move/delete). If anyone
2274 * tried to get the path to the dir items, it would get a path inside that
2275 * orphan directory.
2276 * 3. When an inode is moved around or gets new links, it may overwrite the ref
2277 * of an unprocessed inode. If in that case the first ref would be
2278 * overwritten, the overwritten inode gets "orphanized". Later when we
2279 * process this overwritten inode, it is restored at a new place by moving
2280 * the orphan inode.
2281 *
2282 * sctx->send_progress tells this function at which point in time receiving
2283 * would be.
2284 */
2285static int get_cur_path(struct send_ctx *sctx, u64 ino, u64 gen,
2286 struct fs_path *dest)
2287{
2288 int ret = 0;
2289 struct fs_path *name = NULL;
2290 u64 parent_inode = 0;
2291 u64 parent_gen = 0;
2292 int stop = 0;
2293
924794c9 2294 name = fs_path_alloc();
31db9f7c
AB		 2295 if (!name) {
2296 ret = -ENOMEM;
2297 goto out;
2298 }
2299
2300 dest->reversed = 1;
2301 fs_path_reset(dest);
2302
2303 while (!stop && ino != BTRFS_FIRST_FREE_OBJECTID) {
8b191a68
FM		 2304 struct waiting_dir_move *wdm;
2305
31db9f7c
AB		 2306 fs_path_reset(name);
2307
9dc44214
FM		 2308 if (is_waiting_for_rm(sctx, ino)) {
2309 ret = gen_unique_name(sctx, ino, gen, name);
2310 if (ret < 0)
2311 goto out;
2312 ret = fs_path_add_path(dest, name);
2313 break;
2314 }
2315
8b191a68
FM		 2316 wdm = get_waiting_dir_move(sctx, ino);
2317 if (wdm && wdm->orphanized) {
2318 ret = gen_unique_name(sctx, ino, gen, name);
2319 stop = 1;
2320 } else if (wdm) {
bf0d1f44
FM		 2321 ret = get_first_ref(sctx->parent_root, ino,
2322 &parent_inode, &parent_gen, name);
2323 } else {
2324 ret = __get_cur_name_and_parent(sctx, ino, gen,
2325 &parent_inode,
2326 &parent_gen, name);
2327 if (ret)
2328 stop = 1;
2329 }
2330
31db9f7c
AB		 2331 if (ret < 0)
2332 goto out;
9f03740a 2333
31db9f7c
AB		 2334 ret = fs_path_add_path(dest, name);
2335 if (ret < 0)
2336 goto out;
2337
2338 ino = parent_inode;
2339 gen = parent_gen;
2340 }
2341
2342out:
924794c9 2343 fs_path_free(name);
31db9f7c
AB		 2344 if (!ret)
2345 fs_path_unreverse(dest);
2346 return ret;
2347}
2348
31db9f7c
AB		 2349/*
2350 * Sends a BTRFS_SEND_C_SUBVOL command/item to userspace
2351 */
2352static int send_subvol_begin(struct send_ctx *sctx)
2353{
2354 int ret;
2355 struct btrfs_root *send_root = sctx->send_root;
2356 struct btrfs_root *parent_root = sctx->parent_root;
2357 struct btrfs_path *path;
2358 struct btrfs_key key;
2359 struct btrfs_root_ref *ref;
2360 struct extent_buffer *leaf;
2361 char *name = NULL;
2362 int namelen;
2363
ffcfaf81 2364 path = btrfs_alloc_path();
31db9f7c
AB		 2365 if (!path)
2366 return -ENOMEM;
2367
e780b0d1 2368 name = kmalloc(BTRFS_PATH_NAME_MAX, GFP_KERNEL);
31db9f7c
AB		 2369 if (!name) {
2370 btrfs_free_path(path);
2371 return -ENOMEM;
2372 }
2373
2374 key.objectid = send_root->objectid;
2375 key.type = BTRFS_ROOT_BACKREF_KEY;
2376 key.offset = 0;
2377
2378 ret = btrfs_search_slot_for_read(send_root->fs_info->tree_root,
2379 &key, path, 1, 0);
2380 if (ret < 0)
2381 goto out;
2382 if (ret) {
2383 ret = -ENOENT;
2384 goto out;
2385 }
2386
2387 leaf = path->nodes[0];
2388 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2389 if (key.type != BTRFS_ROOT_BACKREF_KEY ||
2390 key.objectid != send_root->objectid) {
2391 ret = -ENOENT;
2392 goto out;
2393 }
2394 ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_ref);
2395 namelen = btrfs_root_ref_name_len(leaf, ref);
2396 read_extent_buffer(leaf, name, (unsigned long)(ref + 1), namelen);
2397 btrfs_release_path(path);
2398
31db9f7c
AB		 2399 if (parent_root) {
2400 ret = begin_cmd(sctx, BTRFS_SEND_C_SNAPSHOT);
2401 if (ret < 0)
2402 goto out;
2403 } else {
2404 ret = begin_cmd(sctx, BTRFS_SEND_C_SUBVOL);
2405 if (ret < 0)
2406 goto out;
2407 }
2408
2409 TLV_PUT_STRING(sctx, BTRFS_SEND_A_PATH, name, namelen);
b96b1db0
RR		 2410
2411 if (!btrfs_is_empty_uuid(sctx->send_root->root_item.received_uuid))
2412 TLV_PUT_UUID(sctx, BTRFS_SEND_A_UUID,
2413 sctx->send_root->root_item.received_uuid);
2414 else
2415 TLV_PUT_UUID(sctx, BTRFS_SEND_A_UUID,
2416 sctx->send_root->root_item.uuid);
2417
31db9f7c 2418 TLV_PUT_U64(sctx, BTRFS_SEND_A_CTRANSID,
5a0f4e2c 2419 le64_to_cpu(sctx->send_root->root_item.ctransid));
31db9f7c 2420 if (parent_root) {
37b8d27d
JB		 2421 if (!btrfs_is_empty_uuid(parent_root->root_item.received_uuid))
2422 TLV_PUT_UUID(sctx, BTRFS_SEND_A_CLONE_UUID,
2423 parent_root->root_item.received_uuid);
2424 else
2425 TLV_PUT_UUID(sctx, BTRFS_SEND_A_CLONE_UUID,
2426 parent_root->root_item.uuid);
31db9f7c 2427 TLV_PUT_U64(sctx, BTRFS_SEND_A_CLONE_CTRANSID,
5a0f4e2c 2428 le64_to_cpu(sctx->parent_root->root_item.ctransid));
31db9f7c
AB		 2429 }
2430
2431 ret = send_cmd(sctx);
2432
2433tlv_put_failure:
2434out:
2435 btrfs_free_path(path);
2436 kfree(name);
2437 return ret;
2438}
2439
2440static int send_truncate(struct send_ctx *sctx, u64 ino, u64 gen, u64 size)
2441{
04ab956e 2442 struct btrfs_fs_info *fs_info = sctx->send_root->fs_info;
31db9f7c
AB		 2443 int ret = 0;
2444 struct fs_path *p;
2445
04ab956e 2446 btrfs_debug(fs_info, "send_truncate %llu size=%llu", ino, size);
31db9f7c 2447
924794c9 2448 p = fs_path_alloc();
31db9f7c
AB		 2449 if (!p)
2450 return -ENOMEM;
2451
2452 ret = begin_cmd(sctx, BTRFS_SEND_C_TRUNCATE);
2453 if (ret < 0)
2454 goto out;
2455
2456 ret = get_cur_path(sctx, ino, gen, p);
2457 if (ret < 0)
2458 goto out;
2459 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, p);
2460 TLV_PUT_U64(sctx, BTRFS_SEND_A_SIZE, size);
2461
2462 ret = send_cmd(sctx);
2463
2464tlv_put_failure:
2465out:
924794c9 2466 fs_path_free(p);
31db9f7c
AB		 2467 return ret;
2468}
2469
2470static int send_chmod(struct send_ctx *sctx, u64 ino, u64 gen, u64 mode)
2471{
04ab956e 2472 struct btrfs_fs_info *fs_info = sctx->send_root->fs_info;
31db9f7c
AB		 2473 int ret = 0;
2474 struct fs_path *p;
2475
04ab956e 2476 btrfs_debug(fs_info, "send_chmod %llu mode=%llu", ino, mode);
31db9f7c 2477
924794c9 2478 p = fs_path_alloc();
31db9f7c
AB		 2479 if (!p)
2480 return -ENOMEM;
2481
2482 ret = begin_cmd(sctx, BTRFS_SEND_C_CHMOD);
2483 if (ret < 0)
2484 goto out;
2485
2486 ret = get_cur_path(sctx, ino, gen, p);
2487 if (ret < 0)
2488 goto out;
2489 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, p);
2490 TLV_PUT_U64(sctx, BTRFS_SEND_A_MODE, mode & 07777);
2491
2492 ret = send_cmd(sctx);
2493
2494tlv_put_failure:
2495out:
924794c9 2496 fs_path_free(p);
31db9f7c
AB		 2497 return ret;
2498}
2499
2500static int send_chown(struct send_ctx *sctx, u64 ino, u64 gen, u64 uid, u64 gid)
2501{
04ab956e 2502 struct btrfs_fs_info *fs_info = sctx->send_root->fs_info;
31db9f7c
AB		 2503 int ret = 0;
2504 struct fs_path *p;
2505
04ab956e
JM		 2506 btrfs_debug(fs_info, "send_chown %llu uid=%llu, gid=%llu",
2507 ino, uid, gid);
31db9f7c 2508
924794c9 2509 p = fs_path_alloc();
31db9f7c
AB		 2510 if (!p)
2511 return -ENOMEM;
2512
2513 ret = begin_cmd(sctx, BTRFS_SEND_C_CHOWN);
2514 if (ret < 0)
2515 goto out;
2516
2517 ret = get_cur_path(sctx, ino, gen, p);
2518 if (ret < 0)
2519 goto out;
2520 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, p);
2521 TLV_PUT_U64(sctx, BTRFS_SEND_A_UID, uid);
2522 TLV_PUT_U64(sctx, BTRFS_SEND_A_GID, gid);
2523
2524 ret = send_cmd(sctx);
2525
2526tlv_put_failure:
2527out:
924794c9 2528 fs_path_free(p);
31db9f7c
AB		 2529 return ret;
2530}
2531
2532static int send_utimes(struct send_ctx *sctx, u64 ino, u64 gen)
2533{
04ab956e 2534 struct btrfs_fs_info *fs_info = sctx->send_root->fs_info;
31db9f7c
AB		 2535 int ret = 0;
2536 struct fs_path *p = NULL;
2537 struct btrfs_inode_item *ii;
2538 struct btrfs_path *path = NULL;
2539 struct extent_buffer *eb;
2540 struct btrfs_key key;
2541 int slot;
2542
04ab956e 2543 btrfs_debug(fs_info, "send_utimes %llu", ino);
31db9f7c 2544
924794c9 2545 p = fs_path_alloc();
31db9f7c
AB		 2546 if (!p)
2547 return -ENOMEM;
2548
2549 path = alloc_path_for_send();
2550 if (!path) {
2551 ret = -ENOMEM;
2552 goto out;
2553 }
2554
2555 key.objectid = ino;
2556 key.type = BTRFS_INODE_ITEM_KEY;
2557 key.offset = 0;
2558 ret = btrfs_search_slot(NULL, sctx->send_root, &key, path, 0, 0);
15b253ea
FM		 2559 if (ret > 0)
2560 ret = -ENOENT;
31db9f7c
AB		 2561 if (ret < 0)
2562 goto out;
2563
2564 eb = path->nodes[0];
2565 slot = path->slots[0];
2566 ii = btrfs_item_ptr(eb, slot, struct btrfs_inode_item);
2567
2568 ret = begin_cmd(sctx, BTRFS_SEND_C_UTIMES);
2569 if (ret < 0)
2570 goto out;
2571
2572 ret = get_cur_path(sctx, ino, gen, p);
2573 if (ret < 0)
2574 goto out;
2575 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, p);
a937b979
DS		 2576 TLV_PUT_BTRFS_TIMESPEC(sctx, BTRFS_SEND_A_ATIME, eb, &ii->atime);
2577 TLV_PUT_BTRFS_TIMESPEC(sctx, BTRFS_SEND_A_MTIME, eb, &ii->mtime);
2578 TLV_PUT_BTRFS_TIMESPEC(sctx, BTRFS_SEND_A_CTIME, eb, &ii->ctime);
766702ef 2579 /* TODO Add otime support when the otime patches get into upstream */
31db9f7c
AB		 2580
2581 ret = send_cmd(sctx);
2582
2583tlv_put_failure:
2584out:
924794c9 2585 fs_path_free(p);
31db9f7c
AB		 2586 btrfs_free_path(path);
2587 return ret;
2588}
2589
2590/*
2591 * Sends a BTRFS_SEND_C_MKXXX or SYMLINK command to user space. We don't have
2592 * a valid path yet because we did not process the refs yet. So, the inode
2593 * is created as orphan.
2594 */
1f4692da 2595static int send_create_inode(struct send_ctx *sctx, u64 ino)
31db9f7c 2596{
04ab956e 2597 struct btrfs_fs_info *fs_info = sctx->send_root->fs_info;
31db9f7c 2598 int ret = 0;
31db9f7c 2599 struct fs_path *p;
31db9f7c 2600 int cmd;
1f4692da 2601 u64 gen;
31db9f7c 2602 u64 mode;
1f4692da 2603 u64 rdev;
31db9f7c 2604
04ab956e 2605 btrfs_debug(fs_info, "send_create_inode %llu", ino);
31db9f7c 2606
924794c9 2607 p = fs_path_alloc();
31db9f7c
AB		 2608 if (!p)
2609 return -ENOMEM;
2610
644d1940
LB		 2611 if (ino != sctx->cur_ino) {
2612 ret = get_inode_info(sctx->send_root, ino, NULL, &gen, &mode,
2613 NULL, NULL, &rdev);
2614 if (ret < 0)
2615 goto out;
2616 } else {
2617 gen = sctx->cur_inode_gen;
2618 mode = sctx->cur_inode_mode;
2619 rdev = sctx->cur_inode_rdev;
2620 }
31db9f7c 2621
e938c8ad 2622 if (S_ISREG(mode)) {
31db9f7c 2623 cmd = BTRFS_SEND_C_MKFILE;
e938c8ad 2624 } else if (S_ISDIR(mode)) {
31db9f7c 2625 cmd = BTRFS_SEND_C_MKDIR;
e938c8ad 2626 } else if (S_ISLNK(mode)) {
31db9f7c 2627 cmd = BTRFS_SEND_C_SYMLINK;
e938c8ad 2628 } else if (S_ISCHR(mode) || S_ISBLK(mode)) {
31db9f7c 2629 cmd = BTRFS_SEND_C_MKNOD;
e938c8ad 2630 } else if (S_ISFIFO(mode)) {
31db9f7c 2631 cmd = BTRFS_SEND_C_MKFIFO;
e938c8ad 2632 } else if (S_ISSOCK(mode)) {
31db9f7c 2633 cmd = BTRFS_SEND_C_MKSOCK;
e938c8ad 2634 } else {
f14d104d 2635 btrfs_warn(sctx->send_root->fs_info, "unexpected inode type %o",
31db9f7c
AB		 2636 (int)(mode & S_IFMT));
2637 ret = -ENOTSUPP;
2638 goto out;
2639 }
2640
2641 ret = begin_cmd(sctx, cmd);
2642 if (ret < 0)
2643 goto out;
2644
1f4692da 2645 ret = gen_unique_name(sctx, ino, gen, p);
31db9f7c
AB		 2646 if (ret < 0)
2647 goto out;
2648
2649 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, p);
1f4692da 2650 TLV_PUT_U64(sctx, BTRFS_SEND_A_INO, ino);
31db9f7c
AB		 2651
2652 if (S_ISLNK(mode)) {
2653 fs_path_reset(p);
924794c9 2654 ret = read_symlink(sctx->send_root, ino, p);
31db9f7c
AB		 2655 if (ret < 0)
2656 goto out;
2657 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH_LINK, p);
2658 } else if (S_ISCHR(mode) || S_ISBLK(mode) ||
2659 S_ISFIFO(mode) || S_ISSOCK(mode)) {
d79e5043
AJ		 2660 TLV_PUT_U64(sctx, BTRFS_SEND_A_RDEV, new_encode_dev(rdev));
2661 TLV_PUT_U64(sctx, BTRFS_SEND_A_MODE, mode);
31db9f7c
AB		 2662 }
2663
2664 ret = send_cmd(sctx);
2665 if (ret < 0)
2666 goto out;
2667
2668
2669tlv_put_failure:
2670out:
924794c9 2671 fs_path_free(p);
31db9f7c
AB		 2672 return ret;
2673}
2674
1f4692da
AB		 2675/*
2676 * We need some special handling for inodes that get processed before the parent
2677 * directory got created. See process_recorded_refs for details.
2678 * This function does the check if we already created the dir out of order.
2679 */
2680static int did_create_dir(struct send_ctx *sctx, u64 dir)
2681{
2682 int ret = 0;
2683 struct btrfs_path *path = NULL;
2684 struct btrfs_key key;
2685 struct btrfs_key found_key;
2686 struct btrfs_key di_key;
2687 struct extent_buffer *eb;
2688 struct btrfs_dir_item *di;
2689 int slot;
2690
2691 path = alloc_path_for_send();
2692 if (!path) {
2693 ret = -ENOMEM;
2694 goto out;
2695 }
2696
2697 key.objectid = dir;
2698 key.type = BTRFS_DIR_INDEX_KEY;
2699 key.offset = 0;
dff6d0ad
FDBM		 2700 ret = btrfs_search_slot(NULL, sctx->send_root, &key, path, 0, 0);
2701 if (ret < 0)
2702 goto out;
2703
1f4692da 2704 while (1) {
dff6d0ad
FDBM		 2705 eb = path->nodes[0];
2706 slot = path->slots[0];
2707 if (slot >= btrfs_header_nritems(eb)) {
2708 ret = btrfs_next_leaf(sctx->send_root, path);
2709 if (ret < 0) {
2710 goto out;
2711 } else if (ret > 0) {
2712 ret = 0;
2713 break;
2714 }
2715 continue;
1f4692da 2716 }
dff6d0ad
FDBM		 2717
2718 btrfs_item_key_to_cpu(eb, &found_key, slot);
2719 if (found_key.objectid != key.objectid ||
1f4692da
AB		 2720 found_key.type != key.type) {
2721 ret = 0;
2722 goto out;
2723 }
2724
2725 di = btrfs_item_ptr(eb, slot, struct btrfs_dir_item);
2726 btrfs_dir_item_key_to_cpu(eb, di, &di_key);
2727
a0525414
JB		 2728 if (di_key.type != BTRFS_ROOT_ITEM_KEY &&
2729 di_key.objectid < sctx->send_progress) {
1f4692da
AB		 2730 ret = 1;
2731 goto out;
2732 }
2733
dff6d0ad 2734 path->slots[0]++;
1f4692da
AB		 2735 }
2736
2737out:
2738 btrfs_free_path(path);
2739 return ret;
2740}
2741
2742/*
2743 * Only creates the inode if it is:
2744 * 1. Not a directory
2745 * 2. Or a directory which was not created already due to out of order
2746 * directories. See did_create_dir and process_recorded_refs for details.
2747 */
2748static int send_create_inode_if_needed(struct send_ctx *sctx)
2749{
2750 int ret;
2751
2752 if (S_ISDIR(sctx->cur_inode_mode)) {
2753 ret = did_create_dir(sctx, sctx->cur_ino);
2754 if (ret < 0)
2755 goto out;
2756 if (ret) {
2757 ret = 0;
2758 goto out;
2759 }
2760 }
2761
2762 ret = send_create_inode(sctx, sctx->cur_ino);
2763 if (ret < 0)
2764 goto out;
2765
2766out:
2767 return ret;
2768}
2769
31db9f7c
AB		 2770struct recorded_ref {
2771 struct list_head list;
2772 char *dir_path;
2773 char *name;
2774 struct fs_path *full_path;
2775 u64 dir;
2776 u64 dir_gen;
2777 int dir_path_len;
2778 int name_len;
2779};
2780
2781/*
2782 * We need to process new refs before deleted refs, but compare_tree gives us
2783 * everything mixed. So we first record all refs and later process them.
2784 * This function is a helper to record one ref.
2785 */
a4d96d62 2786static int __record_ref(struct list_head *head, u64 dir,
31db9f7c
AB		 2787 u64 dir_gen, struct fs_path *path)
2788{
2789 struct recorded_ref *ref;
31db9f7c 2790
e780b0d1 2791 ref = kmalloc(sizeof(*ref), GFP_KERNEL);
31db9f7c
AB		 2792 if (!ref)
2793 return -ENOMEM;
2794
2795 ref->dir = dir;
2796 ref->dir_gen = dir_gen;
2797 ref->full_path = path;
2798
ed84885d
AS		 2799 ref->name = (char *)kbasename(ref->full_path->start);
2800 ref->name_len = ref->full_path->end - ref->name;
2801 ref->dir_path = ref->full_path->start;
2802 if (ref->name == ref->full_path->start)
31db9f7c 2803 ref->dir_path_len = 0;
ed84885d 2804 else
31db9f7c
AB		 2805 ref->dir_path_len = ref->full_path->end -
2806 ref->full_path->start - 1 - ref->name_len;
31db9f7c
AB		 2807
2808 list_add_tail(&ref->list, head);
2809 return 0;
2810}
2811
ba5e8f2e
JB		 2812static int dup_ref(struct recorded_ref *ref, struct list_head *list)
2813{
2814 struct recorded_ref *new;
2815
e780b0d1 2816 new = kmalloc(sizeof(*ref), GFP_KERNEL);
ba5e8f2e
JB		 2817 if (!new)
2818 return -ENOMEM;
2819
2820 new->dir = ref->dir;
2821 new->dir_gen = ref->dir_gen;
2822 new->full_path = NULL;
2823 INIT_LIST_HEAD(&new->list);
2824 list_add_tail(&new->list, list);
2825 return 0;
2826}
2827
924794c9 2828static void __free_recorded_refs(struct list_head *head)
31db9f7c
AB		 2829{
2830 struct recorded_ref *cur;
31db9f7c 2831
e938c8ad
AB		 2832 while (!list_empty(head)) {
2833 cur = list_entry(head->next, struct recorded_ref, list);
924794c9 2834 fs_path_free(cur->full_path);
e938c8ad 2835 list_del(&cur->list);
31db9f7c
AB		 2836 kfree(cur);
2837 }
31db9f7c
AB		 2838}
2839
2840static void free_recorded_refs(struct send_ctx *sctx)
2841{
924794c9
TI		 2842 __free_recorded_refs(&sctx->new_refs);
2843 __free_recorded_refs(&sctx->deleted_refs);
31db9f7c
AB		 2844}
2845
2846/*
766702ef 2847 * Renames/moves a file/dir to its orphan name. Used when the first
31db9f7c
AB		 2848 * ref of an unprocessed inode gets overwritten and for all non empty
2849 * directories.
2850 */
2851static int orphanize_inode(struct send_ctx *sctx, u64 ino, u64 gen,
2852 struct fs_path *path)
2853{
2854 int ret;
2855 struct fs_path *orphan;
2856
924794c9 2857 orphan = fs_path_alloc();
31db9f7c
AB		 2858 if (!orphan)
2859 return -ENOMEM;
2860
2861 ret = gen_unique_name(sctx, ino, gen, orphan);
2862 if (ret < 0)
2863 goto out;
2864
2865 ret = send_rename(sctx, path, orphan);
2866
2867out:
924794c9 2868 fs_path_free(orphan);
31db9f7c
AB		 2869 return ret;
2870}
2871
9dc44214
FM		 2872static struct orphan_dir_info *
2873add_orphan_dir_info(struct send_ctx *sctx, u64 dir_ino)
2874{
2875 struct rb_node **p = &sctx->orphan_dirs.rb_node;
2876 struct rb_node *parent = NULL;
2877 struct orphan_dir_info *entry, *odi;
2878
e780b0d1 2879 odi = kmalloc(sizeof(*odi), GFP_KERNEL);
9dc44214
FM		 2880 if (!odi)
2881 return ERR_PTR(-ENOMEM);
2882 odi->ino = dir_ino;
2883 odi->gen = 0;
2884
2885 while (*p) {
2886 parent = *p;
2887 entry = rb_entry(parent, struct orphan_dir_info, node);
2888 if (dir_ino < entry->ino) {
2889 p = &(*p)->rb_left;
2890 } else if (dir_ino > entry->ino) {
2891 p = &(*p)->rb_right;
2892 } else {
2893 kfree(odi);
2894 return entry;
2895 }
2896 }
2897
2898 rb_link_node(&odi->node, parent, p);
2899 rb_insert_color(&odi->node, &sctx->orphan_dirs);
2900 return odi;
2901}
2902
2903static struct orphan_dir_info *
2904get_orphan_dir_info(struct send_ctx *sctx, u64 dir_ino)
2905{
2906 struct rb_node *n = sctx->orphan_dirs.rb_node;
2907 struct orphan_dir_info *entry;
2908
2909 while (n) {
2910 entry = rb_entry(n, struct orphan_dir_info, node);
2911 if (dir_ino < entry->ino)
2912 n = n->rb_left;
2913 else if (dir_ino > entry->ino)
2914 n = n->rb_right;
2915 else
2916 return entry;
2917 }
2918 return NULL;
2919}
2920
2921static int is_waiting_for_rm(struct send_ctx *sctx, u64 dir_ino)
2922{
2923 struct orphan_dir_info *odi = get_orphan_dir_info(sctx, dir_ino);
2924
2925 return odi != NULL;
2926}
2927
2928static void free_orphan_dir_info(struct send_ctx *sctx,
2929 struct orphan_dir_info *odi)
2930{
2931 if (!odi)
2932 return;
2933 rb_erase(&odi->node, &sctx->orphan_dirs);
2934 kfree(odi);
2935}
2936
31db9f7c
AB		 2937/*
2938 * Returns 1 if a directory can be removed at this point in time.
2939 * We check this by iterating all dir items and checking if the inode behind
2940 * the dir item was already processed.
2941 */
9dc44214
FM		 2942static int can_rmdir(struct send_ctx *sctx, u64 dir, u64 dir_gen,
2943 u64 send_progress)
31db9f7c
AB		 2944{
2945 int ret = 0;
2946 struct btrfs_root *root = sctx->parent_root;
2947 struct btrfs_path *path;
2948 struct btrfs_key key;
2949 struct btrfs_key found_key;
2950 struct btrfs_key loc;
2951 struct btrfs_dir_item *di;
2952
6d85ed05
AB		 2953 /*
2954 * Don't try to rmdir the top/root subvolume dir.
2955 */
2956 if (dir == BTRFS_FIRST_FREE_OBJECTID)
2957 return 0;
2958
31db9f7c
AB		 2959 path = alloc_path_for_send();
2960 if (!path)
2961 return -ENOMEM;
2962
2963 key.objectid = dir;
2964 key.type = BTRFS_DIR_INDEX_KEY;
2965 key.offset = 0;
dff6d0ad
FDBM		 2966 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2967 if (ret < 0)
2968 goto out;
31db9f7c
AB		 2969
2970 while (1) {
9dc44214
FM		 2971 struct waiting_dir_move *dm;
2972
dff6d0ad
FDBM		 2973 if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
2974 ret = btrfs_next_leaf(root, path);
2975 if (ret < 0)
2976 goto out;
2977 else if (ret > 0)
2978 break;
2979 continue;
31db9f7c 2980 }
dff6d0ad
FDBM		 2981 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
2982 path->slots[0]);
2983 if (found_key.objectid != key.objectid ||
2984 found_key.type != key.type)
31db9f7c 2985 break;
31db9f7c
AB		 2986
2987 di = btrfs_item_ptr(path->nodes[0], path->slots[0],
2988 struct btrfs_dir_item);
2989 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &loc);
2990
9dc44214
FM		 2991 dm = get_waiting_dir_move(sctx, loc.objectid);
2992 if (dm) {
2993 struct orphan_dir_info *odi;
2994
2995 odi = add_orphan_dir_info(sctx, dir);
2996 if (IS_ERR(odi)) {
2997 ret = PTR_ERR(odi);
2998 goto out;
2999 }
3000 odi->gen = dir_gen;
3001 dm->rmdir_ino = dir;
3002 ret = 0;
3003 goto out;
3004 }
3005
31db9f7c 3006 if (loc.objectid > send_progress) {
443f9d26
RK		 3007 struct orphan_dir_info *odi;
3008
3009 odi = get_orphan_dir_info(sctx, dir);
3010 free_orphan_dir_info(sctx, odi);
31db9f7c
AB		 3011 ret = 0;
3012 goto out;
3013 }
3014
dff6d0ad 3015 path->slots[0]++;
31db9f7c
AB		 3016 }
3017
3018 ret = 1;
3019
3020out:
3021 btrfs_free_path(path);
3022 return ret;
3023}
3024
9f03740a
FDBM		 3025static int is_waiting_for_move(struct send_ctx *sctx, u64 ino)
3026{
9dc44214 3027 struct waiting_dir_move *entry = get_waiting_dir_move(sctx, ino);
9f03740a 3028
9dc44214 3029 return entry != NULL;
9f03740a
FDBM		 3030}
3031
8b191a68 3032static int add_waiting_dir_move(struct send_ctx *sctx, u64 ino, bool orphanized)
9f03740a
FDBM		 3033{
3034 struct rb_node **p = &sctx->waiting_dir_moves.rb_node;
3035 struct rb_node *parent = NULL;
3036 struct waiting_dir_move *entry, *dm;
3037
e780b0d1 3038 dm = kmalloc(sizeof(*dm), GFP_KERNEL);
9f03740a
FDBM		 3039 if (!dm)
3040 return -ENOMEM;
3041 dm->ino = ino;
9dc44214 3042 dm->rmdir_ino = 0;
8b191a68 3043 dm->orphanized = orphanized;
9f03740a
FDBM		 3044
3045 while (*p) {
3046 parent = *p;
3047 entry = rb_entry(parent, struct waiting_dir_move, node);
3048 if (ino < entry->ino) {
3049 p = &(*p)->rb_left;
3050 } else if (ino > entry->ino) {
3051 p = &(*p)->rb_right;
3052 } else {
3053 kfree(dm);
3054 return -EEXIST;
3055 }
3056 }
3057
3058 rb_link_node(&dm->node, parent, p);
3059 rb_insert_color(&dm->node, &sctx->waiting_dir_moves);
3060 return 0;
3061}
3062
9dc44214
FM		 3063static struct waiting_dir_move *
3064get_waiting_dir_move(struct send_ctx *sctx, u64 ino)
9f03740a
FDBM		 3065{
3066 struct rb_node *n = sctx->waiting_dir_moves.rb_node;
3067 struct waiting_dir_move *entry;
3068
3069 while (n) {
3070 entry = rb_entry(n, struct waiting_dir_move, node);
9dc44214 3071 if (ino < entry->ino)
9f03740a 3072 n = n->rb_left;
9dc44214 3073 else if (ino > entry->ino)
9f03740a 3074 n = n->rb_right;
9dc44214
FM		 3075 else
3076 return entry;
9f03740a 3077 }
9dc44214
FM		 3078 return NULL;
3079}
3080
3081static void free_waiting_dir_move(struct send_ctx *sctx,
3082 struct waiting_dir_move *dm)
3083{
3084 if (!dm)
3085 return;
3086 rb_erase(&dm->node, &sctx->waiting_dir_moves);
3087 kfree(dm);
9f03740a
FDBM		 3088}
3089
bfa7e1f8
FM		 3090static int add_pending_dir_move(struct send_ctx *sctx,
3091 u64 ino,
3092 u64 ino_gen,
f959492f
FM		 3093 u64 parent_ino,
3094 struct list_head *new_refs,
84471e24
FM		 3095 struct list_head *deleted_refs,
3096 const bool is_orphan)
9f03740a
FDBM		 3097{
3098 struct rb_node **p = &sctx->pending_dir_moves.rb_node;
3099 struct rb_node *parent = NULL;
73b802f4 3100 struct pending_dir_move *entry = NULL, *pm;
9f03740a
FDBM		 3101 struct recorded_ref *cur;
3102 int exists = 0;
3103 int ret;
3104
e780b0d1 3105 pm = kmalloc(sizeof(*pm), GFP_KERNEL);
9f03740a
FDBM		 3106 if (!pm)
3107 return -ENOMEM;
3108 pm->parent_ino = parent_ino;
bfa7e1f8
FM		 3109 pm->ino = ino;
3110 pm->gen = ino_gen;
9f03740a
FDBM		 3111 INIT_LIST_HEAD(&pm->list);
3112 INIT_LIST_HEAD(&pm->update_refs);
3113 RB_CLEAR_NODE(&pm->node);
3114
3115 while (*p) {
3116 parent = *p;
3117 entry = rb_entry(parent, struct pending_dir_move, node);
3118 if (parent_ino < entry->parent_ino) {
3119 p = &(*p)->rb_left;
3120 } else if (parent_ino > entry->parent_ino) {
3121 p = &(*p)->rb_right;
3122 } else {
3123 exists = 1;
3124 break;
3125 }
3126 }
3127
f959492f 3128 list_for_each_entry(cur, deleted_refs, list) {
9f03740a
FDBM		 3129 ret = dup_ref(cur, &pm->update_refs);
3130 if (ret < 0)
3131 goto out;
3132 }
f959492f 3133 list_for_each_entry(cur, new_refs, list) {
9f03740a
FDBM		 3134 ret = dup_ref(cur, &pm->update_refs);
3135 if (ret < 0)
3136 goto out;
3137 }
3138
8b191a68 3139 ret = add_waiting_dir_move(sctx, pm->ino, is_orphan);
9f03740a
FDBM		 3140 if (ret)
3141 goto out;
3142
3143 if (exists) {
3144 list_add_tail(&pm->list, &entry->list);
3145 } else {
3146 rb_link_node(&pm->node, parent, p);
3147 rb_insert_color(&pm->node, &sctx->pending_dir_moves);
3148 }
3149 ret = 0;
3150out:
3151 if (ret) {
3152 __free_recorded_refs(&pm->update_refs);
3153 kfree(pm);
3154 }
3155 return ret;
3156}
3157
3158static struct pending_dir_move *get_pending_dir_moves(struct send_ctx *sctx,
3159 u64 parent_ino)
3160{
3161 struct rb_node *n = sctx->pending_dir_moves.rb_node;
3162 struct pending_dir_move *entry;
3163
3164 while (n) {
3165 entry = rb_entry(n, struct pending_dir_move, node);
3166 if (parent_ino < entry->parent_ino)
3167 n = n->rb_left;
3168 else if (parent_ino > entry->parent_ino)
3169 n = n->rb_right;
3170 else
3171 return entry;
3172 }
3173 return NULL;
3174}
3175
801bec36
RK		 3176static int path_loop(struct send_ctx *sctx, struct fs_path *name,
3177 u64 ino, u64 gen, u64 *ancestor_ino)
3178{
3179 int ret = 0;
3180 u64 parent_inode = 0;
3181 u64 parent_gen = 0;
3182 u64 start_ino = ino;
3183
3184 *ancestor_ino = 0;
3185 while (ino != BTRFS_FIRST_FREE_OBJECTID) {
3186 fs_path_reset(name);
3187
3188 if (is_waiting_for_rm(sctx, ino))
3189 break;
3190 if (is_waiting_for_move(sctx, ino)) {
3191 if (*ancestor_ino == 0)
3192 *ancestor_ino = ino;
3193 ret = get_first_ref(sctx->parent_root, ino,
3194 &parent_inode, &parent_gen, name);
3195 } else {
3196 ret = __get_cur_name_and_parent(sctx, ino, gen,
3197 &parent_inode,
3198 &parent_gen, name);
3199 if (ret > 0) {
3200 ret = 0;
3201 break;
3202 }
3203 }
3204 if (ret < 0)
3205 break;
3206 if (parent_inode == start_ino) {
3207 ret = 1;
3208 if (*ancestor_ino == 0)
3209 *ancestor_ino = ino;
3210 break;
3211 }
3212 ino = parent_inode;
3213 gen = parent_gen;
3214 }
3215 return ret;
3216}
3217
9f03740a
FDBM		 3218static int apply_dir_move(struct send_ctx *sctx, struct pending_dir_move *pm)
3219{
3220 struct fs_path *from_path = NULL;
3221 struct fs_path *to_path = NULL;
2b863a13 3222 struct fs_path *name = NULL;
9f03740a
FDBM		 3223 u64 orig_progress = sctx->send_progress;
3224 struct recorded_ref *cur;
2b863a13 3225 u64 parent_ino, parent_gen;
9dc44214
FM		 3226 struct waiting_dir_move *dm = NULL;
3227 u64 rmdir_ino = 0;
801bec36
RK		 3228 u64 ancestor;
3229 bool is_orphan;
9f03740a
FDBM		 3230 int ret;
3231
2b863a13 3232 name = fs_path_alloc();
9f03740a 3233 from_path = fs_path_alloc();
2b863a13
FM		 3234 if (!name || !from_path) {
3235 ret = -ENOMEM;
3236 goto out;
3237 }
9f03740a 3238
9dc44214
FM		 3239 dm = get_waiting_dir_move(sctx, pm->ino);
3240 ASSERT(dm);
3241 rmdir_ino = dm->rmdir_ino;
801bec36 3242 is_orphan = dm->orphanized;
9dc44214 3243 free_waiting_dir_move(sctx, dm);
2b863a13 3244
801bec36 3245 if (is_orphan) {
84471e24
FM		 3246 ret = gen_unique_name(sctx, pm->ino,
3247 pm->gen, from_path);
3248 } else {
3249 ret = get_first_ref(sctx->parent_root, pm->ino,
3250 &parent_ino, &parent_gen, name);
3251 if (ret < 0)
3252 goto out;
3253 ret = get_cur_path(sctx, parent_ino, parent_gen,
3254 from_path);
3255 if (ret < 0)
3256 goto out;
3257 ret = fs_path_add_path(from_path, name);
3258 }
c992ec94
FM		 3259 if (ret < 0)
3260 goto out;
2b863a13 3261
f959492f 3262 sctx->send_progress = sctx->cur_ino + 1;
801bec36 3263 ret = path_loop(sctx, name, pm->ino, pm->gen, &ancestor);
7969e77a
FM		 3264 if (ret < 0)
3265 goto out;
801bec36
RK		 3266 if (ret) {
3267 LIST_HEAD(deleted_refs);
3268 ASSERT(ancestor > BTRFS_FIRST_FREE_OBJECTID);
3269 ret = add_pending_dir_move(sctx, pm->ino, pm->gen, ancestor,
3270 &pm->update_refs, &deleted_refs,
3271 is_orphan);
3272 if (ret < 0)
3273 goto out;
3274 if (rmdir_ino) {
3275 dm = get_waiting_dir_move(sctx, pm->ino);
3276 ASSERT(dm);
3277 dm->rmdir_ino = rmdir_ino;
3278 }
3279 goto out;
3280 }
c992ec94
FM		 3281 fs_path_reset(name);
3282 to_path = name;
2b863a13 3283 name = NULL;
9f03740a
FDBM		 3284 ret = get_cur_path(sctx, pm->ino, pm->gen, to_path);
3285 if (ret < 0)
3286 goto out;
3287
3288 ret = send_rename(sctx, from_path, to_path);
3289 if (ret < 0)
3290 goto out;
3291
9dc44214
FM		 3292 if (rmdir_ino) {
3293 struct orphan_dir_info *odi;
3294
3295 odi = get_orphan_dir_info(sctx, rmdir_ino);
3296 if (!odi) {
3297 /* already deleted */
3298 goto finish;
3299 }
99ea42dd 3300 ret = can_rmdir(sctx, rmdir_ino, odi->gen, sctx->cur_ino);
9dc44214
FM		 3301 if (ret < 0)
3302 goto out;
3303 if (!ret)
3304 goto finish;
3305
3306 name = fs_path_alloc();
3307 if (!name) {
3308 ret = -ENOMEM;
3309 goto out;
3310 }
3311 ret = get_cur_path(sctx, rmdir_ino, odi->gen, name);
3312 if (ret < 0)
3313 goto out;
3314 ret = send_rmdir(sctx, name);
3315 if (ret < 0)
3316 goto out;
3317 free_orphan_dir_info(sctx, odi);
3318 }
3319
3320finish:
9f03740a
FDBM		 3321 ret = send_utimes(sctx, pm->ino, pm->gen);
3322 if (ret < 0)
3323 goto out;
3324
3325 /*
3326 * After rename/move, need to update the utimes of both new parent(s)
3327 * and old parent(s).
3328 */
3329 list_for_each_entry(cur, &pm->update_refs, list) {
764433a1
RK		 3330 /*
3331 * The parent inode might have been deleted in the send snapshot
3332 */
3333 ret = get_inode_info(sctx->send_root, cur->dir, NULL,
3334 NULL, NULL, NULL, NULL, NULL);
3335 if (ret == -ENOENT) {
3336 ret = 0;
9dc44214 3337 continue;
764433a1
RK		 3338 }
3339 if (ret < 0)
3340 goto out;
3341
9f03740a
FDBM		 3342 ret = send_utimes(sctx, cur->dir, cur->dir_gen);
3343 if (ret < 0)
3344 goto out;
3345 }
3346
3347out:
2b863a13 3348 fs_path_free(name);
9f03740a
FDBM		 3349 fs_path_free(from_path);
3350 fs_path_free(to_path);
3351 sctx->send_progress = orig_progress;
3352
3353 return ret;
3354}
3355
3356static void free_pending_move(struct send_ctx *sctx, struct pending_dir_move *m)
3357{
3358 if (!list_empty(&m->list))
3359 list_del(&m->list);
3360 if (!RB_EMPTY_NODE(&m->node))
3361 rb_erase(&m->node, &sctx->pending_dir_moves);
3362 __free_recorded_refs(&m->update_refs);
3363 kfree(m);
3364}
3365
3366static void tail_append_pending_moves(struct pending_dir_move *moves,
3367 struct list_head *stack)
3368{
3369 if (list_empty(&moves->list)) {
3370 list_add_tail(&moves->list, stack);
3371 } else {
3372 LIST_HEAD(list);
3373 list_splice_init(&moves->list, &list);
3374 list_add_tail(&moves->list, stack);
3375 list_splice_tail(&list, stack);
3376 }
3377}
3378
3379static int apply_children_dir_moves(struct send_ctx *sctx)
3380{
3381 struct pending_dir_move *pm;
3382 struct list_head stack;
3383 u64 parent_ino = sctx->cur_ino;
3384 int ret = 0;
3385
3386 pm = get_pending_dir_moves(sctx, parent_ino);
3387 if (!pm)
3388 return 0;
3389
3390 INIT_LIST_HEAD(&stack);
3391 tail_append_pending_moves(pm, &stack);
3392
3393 while (!list_empty(&stack)) {
3394 pm = list_first_entry(&stack, struct pending_dir_move, list);
3395 parent_ino = pm->ino;
3396 ret = apply_dir_move(sctx, pm);
3397 free_pending_move(sctx, pm);
3398 if (ret)
3399 goto out;
3400 pm = get_pending_dir_moves(sctx, parent_ino);
3401 if (pm)
3402 tail_append_pending_moves(pm, &stack);
3403 }
3404 return 0;
3405
3406out:
3407 while (!list_empty(&stack)) {
3408 pm = list_first_entry(&stack, struct pending_dir_move, list);
3409 free_pending_move(sctx, pm);
3410 }
3411 return ret;
3412}
3413
84471e24
FM		 3414/*
3415 * We might need to delay a directory rename even when no ancestor directory
3416 * (in the send root) with a higher inode number than ours (sctx->cur_ino) was
3417 * renamed. This happens when we rename a directory to the old name (the name
3418 * in the parent root) of some other unrelated directory that got its rename
3419 * delayed due to some ancestor with higher number that got renamed.
3420 *
3421 * Example:
3422 *
3423 * Parent snapshot:
3424 * . (ino 256)
3425 * |---- a/ (ino 257)
3426 * | |---- file (ino 260)
3427 * |
3428 * |---- b/ (ino 258)
3429 * |---- c/ (ino 259)
3430 *
3431 * Send snapshot:
3432 * . (ino 256)
3433 * |---- a/ (ino 258)
3434 * |---- x/ (ino 259)
3435 * |---- y/ (ino 257)
3436 * |----- file (ino 260)
3437 *
3438 * Here we can not rename 258 from 'b' to 'a' without the rename of inode 257
3439 * from 'a' to 'x/y' happening first, which in turn depends on the rename of
3440 * inode 259 from 'c' to 'x'. So the order of rename commands the send stream
3441 * must issue is:
3442 *
3443 * 1 - rename 259 from 'c' to 'x'
3444 * 2 - rename 257 from 'a' to 'x/y'
3445 * 3 - rename 258 from 'b' to 'a'
3446 *
3447 * Returns 1 if the rename of sctx->cur_ino needs to be delayed, 0 if it can
3448 * be done right away and < 0 on error.
3449 */
3450static int wait_for_dest_dir_move(struct send_ctx *sctx,
3451 struct recorded_ref *parent_ref,
3452 const bool is_orphan)
3453{
2ff7e61e 3454 struct btrfs_fs_info *fs_info = sctx->parent_root->fs_info;
84471e24
FM		 3455 struct btrfs_path *path;
3456 struct btrfs_key key;
3457 struct btrfs_key di_key;
3458 struct btrfs_dir_item *di;
3459 u64 left_gen;
3460 u64 right_gen;
3461 int ret = 0;
801bec36 3462 struct waiting_dir_move *wdm;
84471e24
FM		 3463
3464 if (RB_EMPTY_ROOT(&sctx->waiting_dir_moves))
3465 return 0;
3466
3467 path = alloc_path_for_send();
3468 if (!path)
3469 return -ENOMEM;
3470
3471 key.objectid = parent_ref->dir;
3472 key.type = BTRFS_DIR_ITEM_KEY;
3473 key.offset = btrfs_name_hash(parent_ref->name, parent_ref->name_len);
3474
3475 ret = btrfs_search_slot(NULL, sctx->parent_root, &key, path, 0, 0);
3476 if (ret < 0) {
3477 goto out;
3478 } else if (ret > 0) {
3479 ret = 0;
3480 goto out;
3481 }
3482
2ff7e61e
JM		 3483 di = btrfs_match_dir_item_name(fs_info, path, parent_ref->name,
3484 parent_ref->name_len);
84471e24
FM		 3485 if (!di) {
3486 ret = 0;
3487 goto out;
3488 }
3489 /*
3490 * di_key.objectid has the number of the inode that has a dentry in the
3491 * parent directory with the same name that sctx->cur_ino is being
3492 * renamed to. We need to check if that inode is in the send root as
3493 * well and if it is currently marked as an inode with a pending rename,
3494 * if it is, we need to delay the rename of sctx->cur_ino as well, so
3495 * that it happens after that other inode is renamed.
3496 */
3497 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &di_key);
3498 if (di_key.type != BTRFS_INODE_ITEM_KEY) {
3499 ret = 0;
3500 goto out;
3501 }
3502
3503 ret = get_inode_info(sctx->parent_root, di_key.objectid, NULL,
3504 &left_gen, NULL, NULL, NULL, NULL);
3505 if (ret < 0)
3506 goto out;
3507 ret = get_inode_info(sctx->send_root, di_key.objectid, NULL,
3508 &right_gen, NULL, NULL, NULL, NULL);
3509 if (ret < 0) {
3510 if (ret == -ENOENT)
3511 ret = 0;
3512 goto out;
3513 }
3514
3515 /* Different inode, no need to delay the rename of sctx->cur_ino */
3516 if (right_gen != left_gen) {
3517 ret = 0;
3518 goto out;
3519 }
3520
801bec36
RK		 3521 wdm = get_waiting_dir_move(sctx, di_key.objectid);
3522 if (wdm && !wdm->orphanized) {
84471e24
FM		 3523 ret = add_pending_dir_move(sctx,
3524 sctx->cur_ino,
3525 sctx->cur_inode_gen,
3526 di_key.objectid,
3527 &sctx->new_refs,
3528 &sctx->deleted_refs,
3529 is_orphan);
3530 if (!ret)
3531 ret = 1;
3532 }
3533out:
3534 btrfs_free_path(path);
3535 return ret;
3536}
3537
80aa6027
FM		 3538/*
3539 * Check if ino ino1 is an ancestor of inode ino2 in the given root.
3540 * Return 1 if true, 0 if false and < 0 on error.
3541 */
3542static int is_ancestor(struct btrfs_root *root,
3543 const u64 ino1,
3544 const u64 ino1_gen,
3545 const u64 ino2,
3546 struct fs_path *fs_path)
3547{
3548 u64 ino = ino2;
3549
3550 while (ino > BTRFS_FIRST_FREE_OBJECTID) {
3551 int ret;
3552 u64 parent;
3553 u64 parent_gen;
3554
3555 fs_path_reset(fs_path);
3556 ret = get_first_ref(root, ino, &parent, &parent_gen, fs_path);
3557 if (ret < 0) {
3558 if (ret == -ENOENT && ino == ino2)
3559 ret = 0;
3560 return ret;
3561 }
3562 if (parent == ino1)
3563 return parent_gen == ino1_gen ? 1 : 0;
3564 ino = parent;
3565 }
3566 return 0;
3567}
3568
9f03740a 3569static int wait_for_parent_move(struct send_ctx *sctx,
8b191a68
FM		 3570 struct recorded_ref *parent_ref,
3571 const bool is_orphan)
9f03740a 3572{
f959492f 3573 int ret = 0;
9f03740a 3574 u64 ino = parent_ref->dir;
fe9c798d 3575 u64 ino_gen = parent_ref->dir_gen;
9f03740a 3576 u64 parent_ino_before, parent_ino_after;
9f03740a
FDBM		 3577 struct fs_path *path_before = NULL;
3578 struct fs_path *path_after = NULL;
3579 int len1, len2;
9f03740a
FDBM		 3580
3581 path_after = fs_path_alloc();
f959492f
FM		 3582 path_before = fs_path_alloc();
3583 if (!path_after || !path_before) {
9f03740a
FDBM		 3584 ret = -ENOMEM;
3585 goto out;
3586 }
3587
bfa7e1f8 3588 /*
f959492f
FM		 3589 * Our current directory inode may not yet be renamed/moved because some
3590 * ancestor (immediate or not) has to be renamed/moved first. So find if
3591 * such ancestor exists and make sure our own rename/move happens after
80aa6027
FM		 3592 * that ancestor is processed to avoid path build infinite loops (done
3593 * at get_cur_path()).
bfa7e1f8 3594 */
f959492f 3595 while (ino > BTRFS_FIRST_FREE_OBJECTID) {
fe9c798d
FM		 3596 u64 parent_ino_after_gen;
3597
f959492f 3598 if (is_waiting_for_move(sctx, ino)) {
80aa6027
FM		 3599 /*
3600 * If the current inode is an ancestor of ino in the
3601 * parent root, we need to delay the rename of the
3602 * current inode, otherwise don't delayed the rename
3603 * because we can end up with a circular dependency
3604 * of renames, resulting in some directories never
3605 * getting the respective rename operations issued in
3606 * the send stream or getting into infinite path build
3607 * loops.
3608 */
3609 ret = is_ancestor(sctx->parent_root,
3610 sctx->cur_ino, sctx->cur_inode_gen,
3611 ino, path_before);
4122ea64
FM		 3612 if (ret)
3613 break;
f959492f 3614 }
bfa7e1f8
FM		 3615
3616 fs_path_reset(path_before);
3617 fs_path_reset(path_after);
3618
3619 ret = get_first_ref(sctx->send_root, ino, &parent_ino_after,
fe9c798d 3620 &parent_ino_after_gen, path_after);
bfa7e1f8
FM		 3621 if (ret < 0)
3622 goto out;
3623 ret = get_first_ref(sctx->parent_root, ino, &parent_ino_before,
3624 NULL, path_before);
f959492f 3625 if (ret < 0 && ret != -ENOENT) {
bfa7e1f8 3626 goto out;
f959492f 3627 } else if (ret == -ENOENT) {
bf8e8ca6 3628 ret = 0;
f959492f 3629 break;
bfa7e1f8
FM		 3630 }
3631
3632 len1 = fs_path_len(path_before);
3633 len2 = fs_path_len(path_after);
f959492f
FM		 3634 if (ino > sctx->cur_ino &&
3635 (parent_ino_before != parent_ino_after || len1 != len2 ||
3636 memcmp(path_before->start, path_after->start, len1))) {
fe9c798d
FM		 3637 u64 parent_ino_gen;
3638
3639 ret = get_inode_info(sctx->parent_root, ino, NULL,
3640 &parent_ino_gen, NULL, NULL, NULL,
3641 NULL);
3642 if (ret < 0)
3643 goto out;
3644 if (ino_gen == parent_ino_gen) {
3645 ret = 1;
3646 break;
3647 }
bfa7e1f8 3648 }
bfa7e1f8 3649 ino = parent_ino_after;
fe9c798d 3650 ino_gen = parent_ino_after_gen;
bfa7e1f8
FM		 3651 }
3652
9f03740a
FDBM		 3653out:
3654 fs_path_free(path_before);
3655 fs_path_free(path_after);
3656
f959492f
FM		 3657 if (ret == 1) {
3658 ret = add_pending_dir_move(sctx,
3659 sctx->cur_ino,
3660 sctx->cur_inode_gen,
3661 ino,
3662 &sctx->new_refs,
84471e24 3663 &sctx->deleted_refs,
8b191a68 3664 is_orphan);
f959492f
FM		 3665 if (!ret)
3666 ret = 1;
3667 }
3668
9f03740a
FDBM		 3669 return ret;
3670}
3671
31db9f7c
AB		 3672/*
3673 * This does all the move/link/unlink/rmdir magic.
3674 */
9f03740a 3675static int process_recorded_refs(struct send_ctx *sctx, int *pending_move)
31db9f7c 3676{
04ab956e 3677 struct btrfs_fs_info *fs_info = sctx->send_root->fs_info;
31db9f7c
AB		 3678 int ret = 0;
3679 struct recorded_ref *cur;
1f4692da 3680 struct recorded_ref *cur2;
ba5e8f2e 3681 struct list_head check_dirs;
31db9f7c 3682 struct fs_path *valid_path = NULL;
b24baf69 3683 u64 ow_inode = 0;
31db9f7c
AB		 3684 u64 ow_gen;
3685 int did_overwrite = 0;
3686 int is_orphan = 0;
29d6d30f 3687 u64 last_dir_ino_rm = 0;
84471e24 3688 bool can_rename = true;
31db9f7c 3689
04ab956e 3690 btrfs_debug(fs_info, "process_recorded_refs %llu", sctx->cur_ino);
31db9f7c 3691
6d85ed05
AB		 3692 /*
3693 * This should never happen as the root dir always has the same ref
3694 * which is always '..'
3695 */
3696 BUG_ON(sctx->cur_ino <= BTRFS_FIRST_FREE_OBJECTID);
ba5e8f2e 3697 INIT_LIST_HEAD(&check_dirs);
6d85ed05 3698
924794c9 3699 valid_path = fs_path_alloc();
31db9f7c
AB		 3700 if (!valid_path) {
3701 ret = -ENOMEM;
3702 goto out;
3703 }
3704
31db9f7c
AB		 3705 /*
3706 * First, check if the first ref of the current inode was overwritten
3707 * before. If yes, we know that the current inode was already orphanized
3708 * and thus use the orphan name. If not, we can use get_cur_path to
3709 * get the path of the first ref as it would like while receiving at
3710 * this point in time.
3711 * New inodes are always orphan at the beginning, so force to use the
3712 * orphan name in this case.
3713 * The first ref is stored in valid_path and will be updated if it
3714 * gets moved around.
3715 */
3716 if (!sctx->cur_inode_new) {
3717 ret = did_overwrite_first_ref(sctx, sctx->cur_ino,
3718 sctx->cur_inode_gen);
3719 if (ret < 0)
3720 goto out;
3721 if (ret)
3722 did_overwrite = 1;
3723 }
3724 if (sctx->cur_inode_new || did_overwrite) {
3725 ret = gen_unique_name(sctx, sctx->cur_ino,
3726 sctx->cur_inode_gen, valid_path);
3727 if (ret < 0)
3728 goto out;
3729 is_orphan = 1;
3730 } else {
3731 ret = get_cur_path(sctx, sctx->cur_ino, sctx->cur_inode_gen,
3732 valid_path);
3733 if (ret < 0)
3734 goto out;
3735 }
3736
3737 list_for_each_entry(cur, &sctx->new_refs, list) {
1f4692da
AB		 3738 /*
3739 * We may have refs where the parent directory does not exist
3740 * yet. This happens if the parent directories inum is higher
3741 * the the current inum. To handle this case, we create the
3742 * parent directory out of order. But we need to check if this
3743 * did already happen before due to other refs in the same dir.
3744 */
3745 ret = get_cur_inode_state(sctx, cur->dir, cur->dir_gen);
3746 if (ret < 0)
3747 goto out;
3748 if (ret == inode_state_will_create) {
3749 ret = 0;
3750 /*
3751 * First check if any of the current inodes refs did
3752 * already create the dir.
3753 */
3754 list_for_each_entry(cur2, &sctx->new_refs, list) {
3755 if (cur == cur2)
3756 break;
3757 if (cur2->dir == cur->dir) {
3758 ret = 1;
3759 break;
3760 }
3761 }
3762
3763 /*
3764 * If that did not happen, check if a previous inode
3765 * did already create the dir.
3766 */
3767 if (!ret)
3768 ret = did_create_dir(sctx, cur->dir);
3769 if (ret < 0)
3770 goto out;
3771 if (!ret) {
3772 ret = send_create_inode(sctx, cur->dir);
3773 if (ret < 0)
3774 goto out;
3775 }
3776 }
3777
31db9f7c
AB		 3778 /*
3779 * Check if this new ref would overwrite the first ref of
3780 * another unprocessed inode. If yes, orphanize the
3781 * overwritten inode. If we find an overwritten ref that is
3782 * not the first ref, simply unlink it.
3783 */
3784 ret = will_overwrite_ref(sctx, cur->dir, cur->dir_gen,
3785 cur->name, cur->name_len,
3786 &ow_inode, &ow_gen);
3787 if (ret < 0)
3788 goto out;
3789 if (ret) {
924794c9
TI		 3790 ret = is_first_ref(sctx->parent_root,
3791 ow_inode, cur->dir, cur->name,
3792 cur->name_len);
31db9f7c
AB		 3793 if (ret < 0)
3794 goto out;
3795 if (ret) {
8996a48c 3796 struct name_cache_entry *nce;
801bec36 3797 struct waiting_dir_move *wdm;
8996a48c 3798
31db9f7c
AB		 3799 ret = orphanize_inode(sctx, ow_inode, ow_gen,
3800 cur->full_path);
3801 if (ret < 0)
3802 goto out;
801bec36
RK		 3803
3804 /*
3805 * If ow_inode has its rename operation delayed
3806 * make sure that its orphanized name is used in
3807 * the source path when performing its rename
3808 * operation.
3809 */
3810 if (is_waiting_for_move(sctx, ow_inode)) {
3811 wdm = get_waiting_dir_move(sctx,
3812 ow_inode);
3813 ASSERT(wdm);
3814 wdm->orphanized = true;
3815 }
3816
8996a48c
FM		 3817 /*
3818 * Make sure we clear our orphanized inode's
3819 * name from the name cache. This is because the
3820 * inode ow_inode might be an ancestor of some
3821 * other inode that will be orphanized as well
3822 * later and has an inode number greater than
3823 * sctx->send_progress. We need to prevent
3824 * future name lookups from using the old name
3825 * and get instead the orphan name.
3826 */
3827 nce = name_cache_search(sctx, ow_inode, ow_gen);
3828 if (nce) {
3829 name_cache_delete(sctx, nce);
3830 kfree(nce);
3831 }
801bec36
RK		 3832
3833 /*
3834 * ow_inode might currently be an ancestor of
3835 * cur_ino, therefore compute valid_path (the
3836 * current path of cur_ino) again because it
3837 * might contain the pre-orphanization name of
3838 * ow_inode, which is no longer valid.
3839 */
3840 fs_path_reset(valid_path);
3841 ret = get_cur_path(sctx, sctx->cur_ino,
3842 sctx->cur_inode_gen, valid_path);
3843 if (ret < 0)
3844 goto out;
31db9f7c
AB		 3845 } else {
3846 ret = send_unlink(sctx, cur->full_path);
3847 if (ret < 0)
3848 goto out;
3849 }
3850 }
3851
84471e24
FM		 3852 if (S_ISDIR(sctx->cur_inode_mode) && sctx->parent_root) {
3853 ret = wait_for_dest_dir_move(sctx, cur, is_orphan);
3854 if (ret < 0)
3855 goto out;
3856 if (ret == 1) {
3857 can_rename = false;
3858 *pending_move = 1;
3859 }
3860 }
3861
8b191a68
FM		 3862 if (S_ISDIR(sctx->cur_inode_mode) && sctx->parent_root &&
3863 can_rename) {
3864 ret = wait_for_parent_move(sctx, cur, is_orphan);
3865 if (ret < 0)
3866 goto out;
3867 if (ret == 1) {
3868 can_rename = false;
3869 *pending_move = 1;
3870 }
3871 }
3872
31db9f7c
AB		 3873 /*
3874 * link/move the ref to the new place. If we have an orphan
3875 * inode, move it and update valid_path. If not, link or move
3876 * it depending on the inode mode.
3877 */
84471e24 3878 if (is_orphan && can_rename) {
31db9f7c
AB		 3879 ret = send_rename(sctx, valid_path, cur->full_path);
3880 if (ret < 0)
3881 goto out;
3882 is_orphan = 0;
3883 ret = fs_path_copy(valid_path, cur->full_path);
3884 if (ret < 0)
3885 goto out;
84471e24 3886 } else if (can_rename) {
31db9f7c
AB		 3887 if (S_ISDIR(sctx->cur_inode_mode)) {
3888 /*
3889 * Dirs can't be linked, so move it. For moved
3890 * dirs, we always have one new and one deleted
3891 * ref. The deleted ref is ignored later.
3892 */
8b191a68
FM		 3893 ret = send_rename(sctx, valid_path,
3894 cur->full_path);
3895 if (!ret)
3896 ret = fs_path_copy(valid_path,
3897 cur->full_path);
31db9f7c
AB		 3898 if (ret < 0)
3899 goto out;
3900 } else {
3901 ret = send_link(sctx, cur->full_path,
3902 valid_path);
3903 if (ret < 0)
3904 goto out;
3905 }
3906 }
ba5e8f2e 3907 ret = dup_ref(cur, &check_dirs);
31db9f7c
AB		 3908 if (ret < 0)
3909 goto out;
3910 }
3911
3912 if (S_ISDIR(sctx->cur_inode_mode) && sctx->cur_inode_deleted) {
3913 /*
3914 * Check if we can already rmdir the directory. If not,
3915 * orphanize it. For every dir item inside that gets deleted
3916 * later, we do this check again and rmdir it then if possible.
3917 * See the use of check_dirs for more details.
3918 */
9dc44214
FM		 3919 ret = can_rmdir(sctx, sctx->cur_ino, sctx->cur_inode_gen,
3920 sctx->cur_ino);
31db9f7c
AB		 3921 if (ret < 0)
3922 goto out;
3923 if (ret) {
3924 ret = send_rmdir(sctx, valid_path);
3925 if (ret < 0)
3926 goto out;
3927 } else if (!is_orphan) {
3928 ret = orphanize_inode(sctx, sctx->cur_ino,
3929 sctx->cur_inode_gen, valid_path);
3930 if (ret < 0)
3931 goto out;
3932 is_orphan = 1;
3933 }
3934
3935 list_for_each_entry(cur, &sctx->deleted_refs, list) {
ba5e8f2e 3936 ret = dup_ref(cur, &check_dirs);
31db9f7c
AB		 3937 if (ret < 0)
3938 goto out;
3939 }
ccf1626b
AB		 3940 } else if (S_ISDIR(sctx->cur_inode_mode) &&
3941 !list_empty(&sctx->deleted_refs)) {
3942 /*
3943 * We have a moved dir. Add the old parent to check_dirs
3944 */
3945 cur = list_entry(sctx->deleted_refs.next, struct recorded_ref,
3946 list);
ba5e8f2e 3947 ret = dup_ref(cur, &check_dirs);
ccf1626b
AB		 3948 if (ret < 0)
3949 goto out;
31db9f7c
AB		 3950 } else if (!S_ISDIR(sctx->cur_inode_mode)) {
3951 /*
3952 * We have a non dir inode. Go through all deleted refs and
3953 * unlink them if they were not already overwritten by other
3954 * inodes.
3955 */
3956 list_for_each_entry(cur, &sctx->deleted_refs, list) {
3957 ret = did_overwrite_ref(sctx, cur->dir, cur->dir_gen,
3958 sctx->cur_ino, sctx->cur_inode_gen,
3959 cur->name, cur->name_len);
3960 if (ret < 0)
3961 goto out;
3962 if (!ret) {
1f4692da
AB		 3963 ret = send_unlink(sctx, cur->full_path);
3964 if (ret < 0)
3965 goto out;
31db9f7c 3966 }
ba5e8f2e 3967 ret = dup_ref(cur, &check_dirs);
31db9f7c
AB		 3968 if (ret < 0)
3969 goto out;
3970 }
31db9f7c
AB		 3971 /*
3972 * If the inode is still orphan, unlink the orphan. This may
3973 * happen when a previous inode did overwrite the first ref
3974 * of this inode and no new refs were added for the current
766702ef
AB		 3975 * inode. Unlinking does not mean that the inode is deleted in
3976 * all cases. There may still be links to this inode in other
3977 * places.
31db9f7c 3978 */
1f4692da 3979 if (is_orphan) {
31db9f7c
AB		 3980 ret = send_unlink(sctx, valid_path);
3981 if (ret < 0)
3982 goto out;
3983 }
3984 }
3985
3986 /*
3987 * We did collect all parent dirs where cur_inode was once located. We
3988 * now go through all these dirs and check if they are pending for
3989 * deletion and if it's finally possible to perform the rmdir now.
3990 * We also update the inode stats of the parent dirs here.
3991 */
ba5e8f2e 3992 list_for_each_entry(cur, &check_dirs, list) {
766702ef
AB		 3993 /*
3994 * In case we had refs into dirs that were not processed yet,
3995 * we don't need to do the utime and rmdir logic for these dirs.
3996 * The dir will be processed later.
3997 */
ba5e8f2e 3998 if (cur->dir > sctx->cur_ino)
31db9f7c
AB		 3999 continue;
4000
ba5e8f2e 4001 ret = get_cur_inode_state(sctx, cur->dir, cur->dir_gen);
31db9f7c
AB		 4002 if (ret < 0)
4003 goto out;
4004
4005 if (ret == inode_state_did_create ||
4006 ret == inode_state_no_change) {
4007 /* TODO delayed utimes */
ba5e8f2e 4008 ret = send_utimes(sctx, cur->dir, cur->dir_gen);
31db9f7c
AB		 4009 if (ret < 0)
4010 goto out;
29d6d30f
FM		 4011 } else if (ret == inode_state_did_delete &&
4012 cur->dir != last_dir_ino_rm) {
9dc44214
FM		 4013 ret = can_rmdir(sctx, cur->dir, cur->dir_gen,
4014 sctx->cur_ino);
31db9f7c
AB		 4015 if (ret < 0)
4016 goto out;
4017 if (ret) {
ba5e8f2e
JB		 4018 ret = get_cur_path(sctx, cur->dir,
4019 cur->dir_gen, valid_path);
31db9f7c
AB		 4020 if (ret < 0)
4021 goto out;
4022 ret = send_rmdir(sctx, valid_path);
4023 if (ret < 0)
4024 goto out;
29d6d30f 4025 last_dir_ino_rm = cur->dir;
31db9f7c
AB		 4026 }
4027 }
4028 }
4029
31db9f7c
AB		 4030 ret = 0;
4031
4032out:
ba5e8f2e 4033 __free_recorded_refs(&check_dirs);
31db9f7c 4034 free_recorded_refs(sctx);
924794c9 4035 fs_path_free(valid_path);
31db9f7c
AB		 4036 return ret;
4037}
4038
a4d96d62
LB		 4039static int record_ref(struct btrfs_root *root, int num, u64 dir, int index,
4040 struct fs_path *name, void *ctx, struct list_head *refs)
31db9f7c
AB		 4041{
4042 int ret = 0;
4043 struct send_ctx *sctx = ctx;
4044 struct fs_path *p;
4045 u64 gen;
4046
924794c9 4047 p = fs_path_alloc();
31db9f7c
AB		 4048 if (!p)
4049 return -ENOMEM;
4050
a4d96d62 4051 ret = get_inode_info(root, dir, NULL, &gen, NULL, NULL,
85a7b33b 4052 NULL, NULL);
31db9f7c
AB		 4053 if (ret < 0)
4054 goto out;
4055
31db9f7c
AB		 4056 ret = get_cur_path(sctx, dir, gen, p);
4057 if (ret < 0)
4058 goto out;
4059 ret = fs_path_add_path(p, name);
4060 if (ret < 0)
4061 goto out;
4062
a4d96d62 4063 ret = __record_ref(refs, dir, gen, p);
31db9f7c
AB		 4064
4065out:
4066 if (ret)
924794c9 4067 fs_path_free(p);
31db9f7c
AB		 4068 return ret;
4069}
4070
a4d96d62
LB		 4071static int __record_new_ref(int num, u64 dir, int index,
4072 struct fs_path *name,
4073 void *ctx)
4074{
4075 struct send_ctx *sctx = ctx;
4076 return record_ref(sctx->send_root, num, dir, index, name,
4077 ctx, &sctx->new_refs);
4078}
4079
4080
31db9f7c
AB		 4081static int __record_deleted_ref(int num, u64 dir, int index,
4082 struct fs_path *name,
4083 void *ctx)
4084{
31db9f7c 4085 struct send_ctx *sctx = ctx;
a4d96d62
LB		 4086 return record_ref(sctx->parent_root, num, dir, index, name,
4087 ctx, &sctx->deleted_refs);
31db9f7c
AB		 4088}
4089
4090static int record_new_ref(struct send_ctx *sctx)
4091{
4092 int ret;
4093
924794c9
TI		 4094 ret = iterate_inode_ref(sctx->send_root, sctx->left_path,
4095 sctx->cmp_key, 0, __record_new_ref, sctx);
31db9f7c
AB		 4096 if (ret < 0)
4097 goto out;
4098 ret = 0;
4099
4100out:
4101 return ret;
4102}
4103
4104static int record_deleted_ref(struct send_ctx *sctx)
4105{
4106 int ret;
4107
924794c9
TI		 4108 ret = iterate_inode_ref(sctx->parent_root, sctx->right_path,
4109 sctx->cmp_key, 0, __record_deleted_ref, sctx);
31db9f7c
AB		 4110 if (ret < 0)
4111 goto out;
4112 ret = 0;
4113
4114out:
4115 return ret;
4116}
4117
4118struct find_ref_ctx {
4119 u64 dir;
ba5e8f2e
JB		 4120 u64 dir_gen;
4121 struct btrfs_root *root;
31db9f7c
AB		 4122 struct fs_path *name;
4123 int found_idx;
4124};
4125
4126static int __find_iref(int num, u64 dir, int index,
4127 struct fs_path *name,
4128 void *ctx_)
4129{
4130 struct find_ref_ctx *ctx = ctx_;
ba5e8f2e
JB		 4131 u64 dir_gen;
4132 int ret;
31db9f7c
AB		 4133
4134 if (dir == ctx->dir && fs_path_len(name) == fs_path_len(ctx->name) &&
4135 strncmp(name->start, ctx->name->start, fs_path_len(name)) == 0) {
ba5e8f2e
JB		 4136 /*
4137 * To avoid doing extra lookups we'll only do this if everything
4138 * else matches.
4139 */
4140 ret = get_inode_info(ctx->root, dir, NULL, &dir_gen, NULL,
4141 NULL, NULL, NULL);
4142 if (ret)
4143 return ret;
4144 if (dir_gen != ctx->dir_gen)
4145 return 0;
31db9f7c
AB		 4146 ctx->found_idx = num;
4147 return 1;
4148 }
4149 return 0;
4150}
4151
924794c9 4152static int find_iref(struct btrfs_root *root,
31db9f7c
AB		 4153 struct btrfs_path *path,
4154 struct btrfs_key *key,
ba5e8f2e 4155 u64 dir, u64 dir_gen, struct fs_path *name)
31db9f7c
AB		 4156{
4157 int ret;
4158 struct find_ref_ctx ctx;
4159
4160 ctx.dir = dir;
4161 ctx.name = name;
ba5e8f2e 4162 ctx.dir_gen = dir_gen;
31db9f7c 4163 ctx.found_idx = -1;
ba5e8f2e 4164 ctx.root = root;
31db9f7c 4165
924794c9 4166 ret = iterate_inode_ref(root, path, key, 0, __find_iref, &ctx);
31db9f7c
AB		 4167 if (ret < 0)
4168 return ret;
4169
4170 if (ctx.found_idx == -1)
4171 return -ENOENT;
4172
4173 return ctx.found_idx;
4174}
4175
4176static int __record_changed_new_ref(int num, u64 dir, int index,
4177 struct fs_path *name,
4178 void *ctx)
4179{
ba5e8f2e 4180 u64 dir_gen;
31db9f7c
AB		 4181 int ret;
4182 struct send_ctx *sctx = ctx;
4183
ba5e8f2e
JB		 4184 ret = get_inode_info(sctx->send_root, dir, NULL, &dir_gen, NULL,
4185 NULL, NULL, NULL);
4186 if (ret)
4187 return ret;
4188
924794c9 4189 ret = find_iref(sctx->parent_root, sctx->right_path,
ba5e8f2e 4190 sctx->cmp_key, dir, dir_gen, name);
31db9f7c
AB		 4191 if (ret == -ENOENT)
4192 ret = __record_new_ref(num, dir, index, name, sctx);
4193 else if (ret > 0)
4194 ret = 0;
4195
4196 return ret;
4197}
4198
4199static int __record_changed_deleted_ref(int num, u64 dir, int index,
4200 struct fs_path *name,
4201 void *ctx)
4202{
ba5e8f2e 4203 u64 dir_gen;
31db9f7c
AB		 4204 int ret;
4205 struct send_ctx *sctx = ctx;
4206
ba5e8f2e
JB		 4207 ret = get_inode_info(sctx->parent_root, dir, NULL, &dir_gen, NULL,
4208 NULL, NULL, NULL);
4209 if (ret)
4210 return ret;
4211
924794c9 4212 ret = find_iref(sctx->send_root, sctx->left_path, sctx->cmp_key,
ba5e8f2e 4213 dir, dir_gen, name);
31db9f7c
AB		 4214 if (ret == -ENOENT)
4215 ret = __record_deleted_ref(num, dir, index, name, sctx);
4216 else if (ret > 0)
4217 ret = 0;
4218
4219 return ret;
4220}
4221
4222static int record_changed_ref(struct send_ctx *sctx)
4223{
4224 int ret = 0;
4225
924794c9 4226 ret = iterate_inode_ref(sctx->send_root, sctx->left_path,
31db9f7c
AB		 4227 sctx->cmp_key, 0, __record_changed_new_ref, sctx);
4228 if (ret < 0)
4229 goto out;
924794c9 4230 ret = iterate_inode_ref(sctx->parent_root, sctx->right_path,
31db9f7c
AB		 4231 sctx->cmp_key, 0, __record_changed_deleted_ref, sctx);
4232 if (ret < 0)
4233 goto out;
4234 ret = 0;
4235
4236out:
4237 return ret;
4238}
4239
4240/*
4241 * Record and process all refs at once. Needed when an inode changes the
4242 * generation number, which means that it was deleted and recreated.
4243 */
4244static int process_all_refs(struct send_ctx *sctx,
4245 enum btrfs_compare_tree_result cmd)
4246{
4247 int ret;
4248 struct btrfs_root *root;
4249 struct btrfs_path *path;
4250 struct btrfs_key key;
4251 struct btrfs_key found_key;
4252 struct extent_buffer *eb;
4253 int slot;
4254 iterate_inode_ref_t cb;
9f03740a 4255 int pending_move = 0;
31db9f7c
AB		 4256
4257 path = alloc_path_for_send();
4258 if (!path)
4259 return -ENOMEM;
4260
4261 if (cmd == BTRFS_COMPARE_TREE_NEW) {
4262 root = sctx->send_root;
4263 cb = __record_new_ref;
4264 } else if (cmd == BTRFS_COMPARE_TREE_DELETED) {
4265 root = sctx->parent_root;
4266 cb = __record_deleted_ref;
4267 } else {
4d1a63b2
DS		 4268 btrfs_err(sctx->send_root->fs_info,
4269 "Wrong command %d in process_all_refs", cmd);
4270 ret = -EINVAL;
4271 goto out;
31db9f7c
AB		 4272 }
4273
4274 key.objectid = sctx->cmp_key->objectid;
4275 key.type = BTRFS_INODE_REF_KEY;
4276 key.offset = 0;
dff6d0ad
FDBM		 4277 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
4278 if (ret < 0)
4279 goto out;
31db9f7c 4280
dff6d0ad 4281 while (1) {
31db9f7c
AB		 4282 eb = path->nodes[0];
4283 slot = path->slots[0];
dff6d0ad
FDBM		 4284 if (slot >= btrfs_header_nritems(eb)) {
4285 ret = btrfs_next_leaf(root, path);
4286 if (ret < 0)
4287 goto out;
4288 else if (ret > 0)
4289 break;
4290 continue;
4291 }
4292
31db9f7c
AB		 4293 btrfs_item_key_to_cpu(eb, &found_key, slot);
4294
4295 if (found_key.objectid != key.objectid ||
96b5bd77
JS		 4296 (found_key.type != BTRFS_INODE_REF_KEY &&
4297 found_key.type != BTRFS_INODE_EXTREF_KEY))
31db9f7c 4298 break;
31db9f7c 4299
924794c9 4300 ret = iterate_inode_ref(root, path, &found_key, 0, cb, sctx);
31db9f7c
AB		 4301 if (ret < 0)
4302 goto out;
4303
dff6d0ad 4304 path->slots[0]++;
31db9f7c 4305 }
e938c8ad 4306 btrfs_release_path(path);
31db9f7c 4307
3dc09ec8
JB		 4308 /*
4309 * We don't actually care about pending_move as we are simply
4310 * re-creating this inode and will be rename'ing it into place once we
4311 * rename the parent directory.
4312 */
9f03740a 4313 ret = process_recorded_refs(sctx, &pending_move);
31db9f7c
AB		 4314out:
4315 btrfs_free_path(path);
4316 return ret;
4317}
4318
4319static int send_set_xattr(struct send_ctx *sctx,
4320 struct fs_path *path,
4321 const char *name, int name_len,
4322 const char *data, int data_len)
4323{
4324 int ret = 0;
4325
4326 ret = begin_cmd(sctx, BTRFS_SEND_C_SET_XATTR);
4327 if (ret < 0)
4328 goto out;
4329
4330 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, path);
4331 TLV_PUT_STRING(sctx, BTRFS_SEND_A_XATTR_NAME, name, name_len);
4332 TLV_PUT(sctx, BTRFS_SEND_A_XATTR_DATA, data, data_len);
4333
4334 ret = send_cmd(sctx);
4335
4336tlv_put_failure:
4337out:
4338 return ret;
4339}
4340
4341static int send_remove_xattr(struct send_ctx *sctx,
4342 struct fs_path *path,
4343 const char *name, int name_len)
4344{
4345 int ret = 0;
4346
4347 ret = begin_cmd(sctx, BTRFS_SEND_C_REMOVE_XATTR);
4348 if (ret < 0)
4349 goto out;
4350
4351 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, path);
4352 TLV_PUT_STRING(sctx, BTRFS_SEND_A_XATTR_NAME, name, name_len);
4353
4354 ret = send_cmd(sctx);
4355
4356tlv_put_failure:
4357out:
4358 return ret;
4359}
4360
4361static int __process_new_xattr(int num, struct btrfs_key *di_key,
4362 const char *name, int name_len,
4363 const char *data, int data_len,
4364 u8 type, void *ctx)
4365{
4366 int ret;
4367 struct send_ctx *sctx = ctx;
4368 struct fs_path *p;
2211d5ba 4369 struct posix_acl_xattr_header dummy_acl;
31db9f7c 4370
924794c9 4371 p = fs_path_alloc();
31db9f7c
AB		 4372 if (!p)
4373 return -ENOMEM;
4374
4375 /*
01327610 4376 * This hack is needed because empty acls are stored as zero byte
31db9f7c 4377 * data in xattrs. Problem with that is, that receiving these zero byte
01327610 4378 * acls will fail later. To fix this, we send a dummy acl list that
31db9f7c
AB		 4379 * only contains the version number and no entries.
4380 */
4381 if (!strncmp(name, XATTR_NAME_POSIX_ACL_ACCESS, name_len) ||
4382 !strncmp(name, XATTR_NAME_POSIX_ACL_DEFAULT, name_len)) {
4383 if (data_len == 0) {
4384 dummy_acl.a_version =
4385 cpu_to_le32(POSIX_ACL_XATTR_VERSION);
4386 data = (char *)&dummy_acl;
4387 data_len = sizeof(dummy_acl);
4388 }
4389 }
4390
4391 ret = get_cur_path(sctx, sctx->cur_ino, sctx->cur_inode_gen, p);
4392 if (ret < 0)
4393 goto out;
4394
4395 ret = send_set_xattr(sctx, p, name, name_len, data, data_len);
4396
4397out:
924794c9 4398 fs_path_free(p);
31db9f7c
AB		 4399 return ret;
4400}
4401
4402static int __process_deleted_xattr(int num, struct btrfs_key *di_key,
4403 const char *name, int name_len,
4404 const char *data, int data_len,
4405 u8 type, void *ctx)
4406{
4407 int ret;
4408 struct send_ctx *sctx = ctx;
4409 struct fs_path *p;
4410
924794c9 4411 p = fs_path_alloc();
31db9f7c
AB		 4412 if (!p)
4413 return -ENOMEM;
4414
4415 ret = get_cur_path(sctx, sctx->cur_ino, sctx->cur_inode_gen, p);
4416 if (ret < 0)
4417 goto out;
4418
4419 ret = send_remove_xattr(sctx, p, name, name_len);
4420
4421out:
924794c9 4422 fs_path_free(p);
31db9f7c
AB		 4423 return ret;
4424}
4425
4426static int process_new_xattr(struct send_ctx *sctx)
4427{
4428 int ret = 0;
4429
924794c9
TI		 4430 ret = iterate_dir_item(sctx->send_root, sctx->left_path,
4431 sctx->cmp_key, __process_new_xattr, sctx);
31db9f7c
AB		 4432
4433 return ret;
4434}
4435
4436static int process_deleted_xattr(struct send_ctx *sctx)
4437{
e2c89907
MY		 4438 return iterate_dir_item(sctx->parent_root, sctx->right_path,
4439 sctx->cmp_key, __process_deleted_xattr, sctx);
31db9f7c
AB		 4440}
4441
4442struct find_xattr_ctx {
4443 const char *name;
4444 int name_len;
4445 int found_idx;
4446 char *found_data;
4447 int found_data_len;
4448};
4449
4450static int __find_xattr(int num, struct btrfs_key *di_key,
4451 const char *name, int name_len,
4452 const char *data, int data_len,
4453 u8 type, void *vctx)
4454{
4455 struct find_xattr_ctx *ctx = vctx;
4456
4457 if (name_len == ctx->name_len &&
4458 strncmp(name, ctx->name, name_len) == 0) {
4459 ctx->found_idx = num;
4460 ctx->found_data_len = data_len;
e780b0d1 4461 ctx->found_data = kmemdup(data, data_len, GFP_KERNEL);
31db9f7c
AB		 4462 if (!ctx->found_data)
4463 return -ENOMEM;
31db9f7c
AB		 4464 return 1;
4465 }
4466 return 0;
4467}
4468
924794c9 4469static int find_xattr(struct btrfs_root *root,
31db9f7c
AB		 4470 struct btrfs_path *path,
4471 struct btrfs_key *key,
4472 const char *name, int name_len,
4473 char **data, int *data_len)
4474{
4475 int ret;
4476 struct find_xattr_ctx ctx;
4477
4478 ctx.name = name;
4479 ctx.name_len = name_len;
4480 ctx.found_idx = -1;
4481 ctx.found_data = NULL;
4482 ctx.found_data_len = 0;
4483
924794c9 4484 ret = iterate_dir_item(root, path, key, __find_xattr, &ctx);
31db9f7c
AB		 4485 if (ret < 0)
4486 return ret;
4487
4488 if (ctx.found_idx == -1)
4489 return -ENOENT;
4490 if (data) {
4491 *data = ctx.found_data;
4492 *data_len = ctx.found_data_len;
4493 } else {
4494 kfree(ctx.found_data);
4495 }
4496 return ctx.found_idx;
4497}
4498
4499
4500static int __process_changed_new_xattr(int num, struct btrfs_key *di_key,
4501 const char *name, int name_len,
4502 const char *data, int data_len,
4503 u8 type, void *ctx)
4504{
4505 int ret;
4506 struct send_ctx *sctx = ctx;
4507 char *found_data = NULL;
4508 int found_data_len = 0;
31db9f7c 4509
924794c9
TI		 4510 ret = find_xattr(sctx->parent_root, sctx->right_path,
4511 sctx->cmp_key, name, name_len, &found_data,
4512 &found_data_len);
31db9f7c
AB		 4513 if (ret == -ENOENT) {
4514 ret = __process_new_xattr(num, di_key, name, name_len, data,
4515 data_len, type, ctx);
4516 } else if (ret >= 0) {
4517 if (data_len != found_data_len ||
4518 memcmp(data, found_data, data_len)) {
4519 ret = __process_new_xattr(num, di_key, name, name_len,
4520 data, data_len, type, ctx);
4521 } else {
4522 ret = 0;
4523 }
4524 }
4525
4526 kfree(found_data);
31db9f7c
AB		 4527 return ret;
4528}
4529
4530static int __process_changed_deleted_xattr(int num, struct btrfs_key *di_key,
4531 const char *name, int name_len,
4532 const char *data, int data_len,
4533 u8 type, void *ctx)
4534{
4535 int ret;
4536 struct send_ctx *sctx = ctx;
4537
924794c9
TI		 4538 ret = find_xattr(sctx->send_root, sctx->left_path, sctx->cmp_key,
4539 name, name_len, NULL, NULL);
31db9f7c
AB		 4540 if (ret == -ENOENT)
4541 ret = __process_deleted_xattr(num, di_key, name, name_len, data,
4542 data_len, type, ctx);
4543 else if (ret >= 0)
4544 ret = 0;
4545
4546 return ret;
4547}
4548
4549static int process_changed_xattr(struct send_ctx *sctx)
4550{
4551 int ret = 0;
4552
924794c9 4553 ret = iterate_dir_item(sctx->send_root, sctx->left_path,
31db9f7c
AB		 4554 sctx->cmp_key, __process_changed_new_xattr, sctx);
4555 if (ret < 0)
4556 goto out;
924794c9 4557 ret = iterate_dir_item(sctx->parent_root, sctx->right_path,
31db9f7c
AB		 4558 sctx->cmp_key, __process_changed_deleted_xattr, sctx);
4559
4560out:
4561 return ret;
4562}
4563
4564static int process_all_new_xattrs(struct send_ctx *sctx)
4565{
4566 int ret;
4567 struct btrfs_root *root;
4568 struct btrfs_path *path;
4569 struct btrfs_key key;
4570 struct btrfs_key found_key;
4571 struct extent_buffer *eb;
4572 int slot;
4573
4574 path = alloc_path_for_send();
4575 if (!path)
4576 return -ENOMEM;
4577
4578 root = sctx->send_root;
4579
4580 key.objectid = sctx->cmp_key->objectid;
4581 key.type = BTRFS_XATTR_ITEM_KEY;
4582 key.offset = 0;
dff6d0ad
FDBM		 4583 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
4584 if (ret < 0)
4585 goto out;
31db9f7c 4586
dff6d0ad 4587 while (1) {
31db9f7c
AB		 4588 eb = path->nodes[0];
4589 slot = path->slots[0];
dff6d0ad
FDBM		 4590 if (slot >= btrfs_header_nritems(eb)) {
4591 ret = btrfs_next_leaf(root, path);
4592 if (ret < 0) {
4593 goto out;
4594 } else if (ret > 0) {
4595 ret = 0;
4596 break;
4597 }
4598 continue;
4599 }
31db9f7c 4600
dff6d0ad 4601 btrfs_item_key_to_cpu(eb, &found_key, slot);
31db9f7c
AB		 4602 if (found_key.objectid != key.objectid ||
4603 found_key.type != key.type) {
4604 ret = 0;
4605 goto out;
4606 }
4607
924794c9
TI		 4608 ret = iterate_dir_item(root, path, &found_key,
4609 __process_new_xattr, sctx);
31db9f7c
AB		 4610 if (ret < 0)
4611 goto out;
4612
dff6d0ad 4613 path->slots[0]++;
31db9f7c
AB		 4614 }
4615
4616out:
4617 btrfs_free_path(path);
4618 return ret;
4619}
4620
ed259095
JB		 4621static ssize_t fill_read_buf(struct send_ctx *sctx, u64 offset, u32 len)
4622{
4623 struct btrfs_root *root = sctx->send_root;
4624 struct btrfs_fs_info *fs_info = root->fs_info;
4625 struct inode *inode;
4626 struct page *page;
4627 char *addr;
4628 struct btrfs_key key;
09cbfeaf 4629 pgoff_t index = offset >> PAGE_SHIFT;
ed259095 4630 pgoff_t last_index;
09cbfeaf 4631 unsigned pg_offset = offset & ~PAGE_MASK;
ed259095
JB		 4632 ssize_t ret = 0;
4633
4634 key.objectid = sctx->cur_ino;
4635 key.type = BTRFS_INODE_ITEM_KEY;
4636 key.offset = 0;
4637
4638 inode = btrfs_iget(fs_info->sb, &key, root, NULL);
4639 if (IS_ERR(inode))
4640 return PTR_ERR(inode);
4641
4642 if (offset + len > i_size_read(inode)) {
4643 if (offset > i_size_read(inode))
4644 len = 0;
4645 else
4646 len = offset - i_size_read(inode);
4647 }
4648 if (len == 0)
4649 goto out;
4650
09cbfeaf 4651 last_index = (offset + len - 1) >> PAGE_SHIFT;
2131bcd3
LB		 4652
4653 /* initial readahead */
4654 memset(&sctx->ra, 0, sizeof(struct file_ra_state));
4655 file_ra_state_init(&sctx->ra, inode->i_mapping);
4656 btrfs_force_ra(inode->i_mapping, &sctx->ra, NULL, index,
4657 last_index - index + 1);
4658
ed259095
JB		 4659 while (index <= last_index) {
4660 unsigned cur_len = min_t(unsigned, len,
09cbfeaf 4661 PAGE_SIZE - pg_offset);
e780b0d1 4662 page = find_or_create_page(inode->i_mapping, index, GFP_KERNEL);
ed259095
JB		 4663 if (!page) {
4664 ret = -ENOMEM;
4665 break;
4666 }
4667
4668 if (!PageUptodate(page)) {
4669 btrfs_readpage(NULL, page);
4670 lock_page(page);
4671 if (!PageUptodate(page)) {
4672 unlock_page(page);
09cbfeaf 4673 put_page(page);
ed259095
JB		 4674 ret = -EIO;
4675 break;
4676 }
4677 }
4678
4679 addr = kmap(page);
4680 memcpy(sctx->read_buf + ret, addr + pg_offset, cur_len);
4681 kunmap(page);
4682 unlock_page(page);
09cbfeaf 4683 put_page(page);
ed259095
JB		 4684 index++;
4685 pg_offset = 0;
4686 len -= cur_len;
4687 ret += cur_len;
4688 }
4689out:
4690 iput(inode);
4691 return ret;
4692}
4693
31db9f7c
AB		 4694/*
4695 * Read some bytes from the current inode/file and send a write command to
4696 * user space.
4697 */
4698static int send_write(struct send_ctx *sctx, u64 offset, u32 len)
4699{
04ab956e 4700 struct btrfs_fs_info *fs_info = sctx->send_root->fs_info;
31db9f7c
AB		 4701 int ret = 0;
4702 struct fs_path *p;
ed259095 4703 ssize_t num_read = 0;
31db9f7c 4704
924794c9 4705 p = fs_path_alloc();
31db9f7c
AB		 4706 if (!p)
4707 return -ENOMEM;
4708
04ab956e 4709 btrfs_debug(fs_info, "send_write offset=%llu, len=%d", offset, len);
31db9f7c 4710
ed259095
JB		 4711 num_read = fill_read_buf(sctx, offset, len);
4712 if (num_read <= 0) {
4713 if (num_read < 0)
4714 ret = num_read;
31db9f7c 4715 goto out;
ed259095 4716 }
31db9f7c
AB		 4717
4718 ret = begin_cmd(sctx, BTRFS_SEND_C_WRITE);
4719 if (ret < 0)
4720 goto out;
4721
4722 ret = get_cur_path(sctx, sctx->cur_ino, sctx->cur_inode_gen, p);
4723 if (ret < 0)
4724 goto out;
4725
4726 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, p);
4727 TLV_PUT_U64(sctx, BTRFS_SEND_A_FILE_OFFSET, offset);
e938c8ad 4728 TLV_PUT(sctx, BTRFS_SEND_A_DATA, sctx->read_buf, num_read);
31db9f7c
AB		 4729
4730 ret = send_cmd(sctx);
4731
4732tlv_put_failure:
4733out:
924794c9 4734 fs_path_free(p);
31db9f7c
AB		 4735 if (ret < 0)
4736 return ret;
e938c8ad 4737 return num_read;
31db9f7c
AB		 4738}
4739
4740/*
4741 * Send a clone command to user space.
4742 */
4743static int send_clone(struct send_ctx *sctx,
4744 u64 offset, u32 len,
4745 struct clone_root *clone_root)
4746{
4747 int ret = 0;
31db9f7c
AB		 4748 struct fs_path *p;
4749 u64 gen;
4750
04ab956e
JM		 4751 btrfs_debug(sctx->send_root->fs_info,
4752 "send_clone offset=%llu, len=%d, clone_root=%llu, clone_inode=%llu, clone_offset=%llu",
4753 offset, len, clone_root->root->objectid, clone_root->ino,
4754 clone_root->offset);
31db9f7c 4755
924794c9 4756 p = fs_path_alloc();
31db9f7c
AB		 4757 if (!p)
4758 return -ENOMEM;
4759
4760 ret = begin_cmd(sctx, BTRFS_SEND_C_CLONE);
4761 if (ret < 0)
4762 goto out;
4763
4764 ret = get_cur_path(sctx, sctx->cur_ino, sctx->cur_inode_gen, p);
4765 if (ret < 0)
4766 goto out;
4767
4768 TLV_PUT_U64(sctx, BTRFS_SEND_A_FILE_OFFSET, offset);
4769 TLV_PUT_U64(sctx, BTRFS_SEND_A_CLONE_LEN, len);
4770 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, p);
4771
e938c8ad 4772 if (clone_root->root == sctx->send_root) {
31db9f7c 4773 ret = get_inode_info(sctx->send_root, clone_root->ino, NULL,
85a7b33b 4774 &gen, NULL, NULL, NULL, NULL);
31db9f7c
AB		 4775 if (ret < 0)
4776 goto out;
4777 ret = get_cur_path(sctx, clone_root->ino, gen, p);
4778 } else {
924794c9 4779 ret = get_inode_path(clone_root->root, clone_root->ino, p);
31db9f7c
AB		 4780 }
4781 if (ret < 0)
4782 goto out;
4783
37b8d27d
JB		 4784 /*
4785 * If the parent we're using has a received_uuid set then use that as
4786 * our clone source as that is what we will look for when doing a
4787 * receive.
4788 *
4789 * This covers the case that we create a snapshot off of a received
4790 * subvolume and then use that as the parent and try to receive on a
4791 * different host.
4792 */
4793 if (!btrfs_is_empty_uuid(clone_root->root->root_item.received_uuid))
4794 TLV_PUT_UUID(sctx, BTRFS_SEND_A_CLONE_UUID,
4795 clone_root->root->root_item.received_uuid);
4796 else
4797 TLV_PUT_UUID(sctx, BTRFS_SEND_A_CLONE_UUID,
4798 clone_root->root->root_item.uuid);
31db9f7c 4799 TLV_PUT_U64(sctx, BTRFS_SEND_A_CLONE_CTRANSID,
5a0f4e2c 4800 le64_to_cpu(clone_root->root->root_item.ctransid));
31db9f7c
AB		 4801 TLV_PUT_PATH(sctx, BTRFS_SEND_A_CLONE_PATH, p);
4802 TLV_PUT_U64(sctx, BTRFS_SEND_A_CLONE_OFFSET,
4803 clone_root->offset);
4804
4805 ret = send_cmd(sctx);
4806
4807tlv_put_failure:
4808out:
924794c9 4809 fs_path_free(p);
31db9f7c
AB		 4810 return ret;
4811}
4812
cb95e7bf
MF		 4813/*
4814 * Send an update extent command to user space.
4815 */
4816static int send_update_extent(struct send_ctx *sctx,
4817 u64 offset, u32 len)
4818{
4819 int ret = 0;
4820 struct fs_path *p;
4821
924794c9 4822 p = fs_path_alloc();
cb95e7bf
MF		 4823 if (!p)
4824 return -ENOMEM;
4825
4826 ret = begin_cmd(sctx, BTRFS_SEND_C_UPDATE_EXTENT);
4827 if (ret < 0)
4828 goto out;
4829
4830 ret = get_cur_path(sctx, sctx->cur_ino, sctx->cur_inode_gen, p);
4831 if (ret < 0)
4832 goto out;
4833
4834 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, p);
4835 TLV_PUT_U64(sctx, BTRFS_SEND_A_FILE_OFFSET, offset);
4836 TLV_PUT_U64(sctx, BTRFS_SEND_A_SIZE, len);
4837
4838 ret = send_cmd(sctx);
4839
4840tlv_put_failure:
4841out:
924794c9 4842 fs_path_free(p);
cb95e7bf
MF		 4843 return ret;
4844}
4845
16e7549f
JB		 4846static int send_hole(struct send_ctx *sctx, u64 end)
4847{
4848 struct fs_path *p = NULL;
4849 u64 offset = sctx->cur_inode_last_extent;
4850 u64 len;
4851 int ret = 0;
4852
4853 p = fs_path_alloc();
4854 if (!p)
4855 return -ENOMEM;
c715e155
FM		 4856 ret = get_cur_path(sctx, sctx->cur_ino, sctx->cur_inode_gen, p);
4857 if (ret < 0)
4858 goto tlv_put_failure;
16e7549f
JB		 4859 memset(sctx->read_buf, 0, BTRFS_SEND_READ_SIZE);
4860 while (offset < end) {
4861 len = min_t(u64, end - offset, BTRFS_SEND_READ_SIZE);
4862
4863 ret = begin_cmd(sctx, BTRFS_SEND_C_WRITE);
16e7549f
JB		 4864 if (ret < 0)
4865 break;
4866 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, p);
4867 TLV_PUT_U64(sctx, BTRFS_SEND_A_FILE_OFFSET, offset);
4868 TLV_PUT(sctx, BTRFS_SEND_A_DATA, sctx->read_buf, len);
4869 ret = send_cmd(sctx);
4870 if (ret < 0)
4871 break;
4872 offset += len;
4873 }
4874tlv_put_failure:
4875 fs_path_free(p);
4876 return ret;
4877}
4878
d906d49f
FM		 4879static int send_extent_data(struct send_ctx *sctx,
4880 const u64 offset,
4881 const u64 len)
4882{
4883 u64 sent = 0;
4884
4885 if (sctx->flags & BTRFS_SEND_FLAG_NO_FILE_DATA)
4886 return send_update_extent(sctx, offset, len);
4887
4888 while (sent < len) {
4889 u64 size = len - sent;
4890 int ret;
4891
4892 if (size > BTRFS_SEND_READ_SIZE)
4893 size = BTRFS_SEND_READ_SIZE;
4894 ret = send_write(sctx, offset + sent, size);
4895 if (ret < 0)
4896 return ret;
4897 if (!ret)
4898 break;
4899 sent += ret;
4900 }
4901 return 0;
4902}
4903
4904static int clone_range(struct send_ctx *sctx,
4905 struct clone_root *clone_root,
4906 const u64 disk_byte,
4907 u64 data_offset,
4908 u64 offset,
4909 u64 len)
4910{
4911 struct btrfs_path *path;
4912 struct btrfs_key key;
4913 int ret;
4914
4915 path = alloc_path_for_send();
4916 if (!path)
4917 return -ENOMEM;
4918
4919 /*
4920 * We can't send a clone operation for the entire range if we find
4921 * extent items in the respective range in the source file that
4922 * refer to different extents or if we find holes.
4923 * So check for that and do a mix of clone and regular write/copy
4924 * operations if needed.
4925 *
4926 * Example:
4927 *
4928 * mkfs.btrfs -f /dev/sda
4929 * mount /dev/sda /mnt
4930 * xfs_io -f -c "pwrite -S 0xaa 0K 100K" /mnt/foo
4931 * cp --reflink=always /mnt/foo /mnt/bar
4932 * xfs_io -c "pwrite -S 0xbb 50K 50K" /mnt/foo
4933 * btrfs subvolume snapshot -r /mnt /mnt/snap
4934 *
4935 * If when we send the snapshot and we are processing file bar (which
4936 * has a higher inode number than foo) we blindly send a clone operation
4937 * for the [0, 100K[ range from foo to bar, the receiver ends up getting
4938 * a file bar that matches the content of file foo - iow, doesn't match
4939 * the content from bar in the original filesystem.
4940 */
4941 key.objectid = clone_root->ino;
4942 key.type = BTRFS_EXTENT_DATA_KEY;
4943 key.offset = clone_root->offset;
4944 ret = btrfs_search_slot(NULL, clone_root->root, &key, path, 0, 0);
4945 if (ret < 0)
4946 goto out;
4947 if (ret > 0 && path->slots[0] > 0) {
4948 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0] - 1);
4949 if (key.objectid == clone_root->ino &&
4950 key.type == BTRFS_EXTENT_DATA_KEY)
4951 path->slots[0]--;
4952 }
4953
4954 while (true) {
4955 struct extent_buffer *leaf = path->nodes[0];
4956 int slot = path->slots[0];
4957 struct btrfs_file_extent_item *ei;
4958 u8 type;
4959 u64 ext_len;
4960 u64 clone_len;
4961
4962 if (slot >= btrfs_header_nritems(leaf)) {
4963 ret = btrfs_next_leaf(clone_root->root, path);
4964 if (ret < 0)
4965 goto out;
4966 else if (ret > 0)
4967 break;
4968 continue;
4969 }
4970
4971 btrfs_item_key_to_cpu(leaf, &key, slot);
4972
4973 /*
4974 * We might have an implicit trailing hole (NO_HOLES feature
4975 * enabled). We deal with it after leaving this loop.
4976 */
4977 if (key.objectid != clone_root->ino ||
4978 key.type != BTRFS_EXTENT_DATA_KEY)
4979 break;
4980
4981 ei = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
4982 type = btrfs_file_extent_type(leaf, ei);
4983 if (type == BTRFS_FILE_EXTENT_INLINE) {
4984 ext_len = btrfs_file_extent_inline_len(leaf, slot, ei);
09cbfeaf 4985 ext_len = PAGE_ALIGN(ext_len);
d906d49f
FM		 4986 } else {
4987 ext_len = btrfs_file_extent_num_bytes(leaf, ei);
4988 }
4989
4990 if (key.offset + ext_len <= clone_root->offset)
4991 goto next;
4992
4993 if (key.offset > clone_root->offset) {
4994 /* Implicit hole, NO_HOLES feature enabled. */
4995 u64 hole_len = key.offset - clone_root->offset;
4996
4997 if (hole_len > len)
4998 hole_len = len;
4999 ret = send_extent_data(sctx, offset, hole_len);
5000 if (ret < 0)
5001 goto out;
5002
5003 len -= hole_len;
5004 if (len == 0)
5005 break;
5006 offset += hole_len;
5007 clone_root->offset += hole_len;
5008 data_offset += hole_len;
5009 }
5010
5011 if (key.offset >= clone_root->offset + len)
5012 break;
5013
5014 clone_len = min_t(u64, ext_len, len);
5015
5016 if (btrfs_file_extent_disk_bytenr(leaf, ei) == disk_byte &&
5017 btrfs_file_extent_offset(leaf, ei) == data_offset)
5018 ret = send_clone(sctx, offset, clone_len, clone_root);
5019 else
5020 ret = send_extent_data(sctx, offset, clone_len);
5021
5022 if (ret < 0)
5023 goto out;
5024
5025 len -= clone_len;
5026 if (len == 0)
5027 break;
5028 offset += clone_len;
5029 clone_root->offset += clone_len;
5030 data_offset += clone_len;
5031next:
5032 path->slots[0]++;
5033 }
5034
5035 if (len > 0)
5036 ret = send_extent_data(sctx, offset, len);
5037 else
5038 ret = 0;
5039out:
5040 btrfs_free_path(path);
5041 return ret;
5042}
5043
31db9f7c
AB		 5044static int send_write_or_clone(struct send_ctx *sctx,
5045 struct btrfs_path *path,
5046 struct btrfs_key *key,
5047 struct clone_root *clone_root)
5048{
5049 int ret = 0;
5050 struct btrfs_file_extent_item *ei;
5051 u64 offset = key->offset;
31db9f7c 5052 u64 len;
31db9f7c 5053 u8 type;
28e5dd8f 5054 u64 bs = sctx->send_root->fs_info->sb->s_blocksize;
31db9f7c
AB		 5055
5056 ei = btrfs_item_ptr(path->nodes[0], path->slots[0],
5057 struct btrfs_file_extent_item);
5058 type = btrfs_file_extent_type(path->nodes[0], ei);
74dd17fb 5059 if (type == BTRFS_FILE_EXTENT_INLINE) {
514ac8ad
CM		 5060 len = btrfs_file_extent_inline_len(path->nodes[0],
5061 path->slots[0], ei);
74dd17fb
CM		 5062 /*
5063 * it is possible the inline item won't cover the whole page,
5064 * but there may be items after this page. Make
5065 * sure to send the whole thing
5066 */
09cbfeaf 5067 len = PAGE_ALIGN(len);
74dd17fb 5068 } else {
31db9f7c 5069 len = btrfs_file_extent_num_bytes(path->nodes[0], ei);
74dd17fb 5070 }
31db9f7c
AB		 5071
5072 if (offset + len > sctx->cur_inode_size)
5073 len = sctx->cur_inode_size - offset;
5074 if (len == 0) {
5075 ret = 0;
5076 goto out;
5077 }
5078
28e5dd8f 5079 if (clone_root && IS_ALIGNED(offset + len, bs)) {
d906d49f
FM		 5080 u64 disk_byte;
5081 u64 data_offset;
5082
5083 disk_byte = btrfs_file_extent_disk_bytenr(path->nodes[0], ei);
5084 data_offset = btrfs_file_extent_offset(path->nodes[0], ei);
5085 ret = clone_range(sctx, clone_root, disk_byte, data_offset,
5086 offset, len);
cb95e7bf 5087 } else {
d906d49f 5088 ret = send_extent_data(sctx, offset, len);
31db9f7c 5089 }
31db9f7c
AB		 5090out:
5091 return ret;
5092}
5093
5094static int is_extent_unchanged(struct send_ctx *sctx,
5095 struct btrfs_path *left_path,
5096 struct btrfs_key *ekey)
5097{
5098 int ret = 0;
5099 struct btrfs_key key;
5100 struct btrfs_path *path = NULL;
5101 struct extent_buffer *eb;
5102 int slot;
5103 struct btrfs_key found_key;
5104 struct btrfs_file_extent_item *ei;
5105 u64 left_disknr;
5106 u64 right_disknr;
5107 u64 left_offset;
5108 u64 right_offset;
5109 u64 left_offset_fixed;
5110 u64 left_len;
5111 u64 right_len;
74dd17fb
CM		 5112 u64 left_gen;
5113 u64 right_gen;
31db9f7c
AB		 5114 u8 left_type;
5115 u8 right_type;
5116
5117 path = alloc_path_for_send();
5118 if (!path)
5119 return -ENOMEM;
5120
5121 eb = left_path->nodes[0];
5122 slot = left_path->slots[0];
31db9f7c
AB		 5123 ei = btrfs_item_ptr(eb, slot, struct btrfs_file_extent_item);
5124 left_type = btrfs_file_extent_type(eb, ei);
31db9f7c
AB		 5125
5126 if (left_type != BTRFS_FILE_EXTENT_REG) {
5127 ret = 0;
5128 goto out;
5129 }
74dd17fb
CM		 5130 left_disknr = btrfs_file_extent_disk_bytenr(eb, ei);
5131 left_len = btrfs_file_extent_num_bytes(eb, ei);
5132 left_offset = btrfs_file_extent_offset(eb, ei);
5133 left_gen = btrfs_file_extent_generation(eb, ei);
31db9f7c
AB		 5134
5135 /*
5136 * Following comments will refer to these graphics. L is the left
5137 * extents which we are checking at the moment. 1-8 are the right
5138 * extents that we iterate.
5139 *
5140 * |-----L-----|
5141 * |-1-|-2a-|-3-|-4-|-5-|-6-|
5142 *
5143 * |-----L-----|
5144 * |--1--|-2b-|...(same as above)
5145 *
5146 * Alternative situation. Happens on files where extents got split.
5147 * |-----L-----|
5148 * |-----------7-----------|-6-|
5149 *
5150 * Alternative situation. Happens on files which got larger.
5151 * |-----L-----|
5152 * |-8-|
5153 * Nothing follows after 8.
5154 */
5155
5156 key.objectid = ekey->objectid;
5157 key.type = BTRFS_EXTENT_DATA_KEY;
5158 key.offset = ekey->offset;
5159 ret = btrfs_search_slot_for_read(sctx->parent_root, &key, path, 0, 0);
5160 if (ret < 0)
5161 goto out;
5162 if (ret) {
5163 ret = 0;
5164 goto out;
5165 }
5166
5167 /*
5168 * Handle special case where the right side has no extents at all.
5169 */
5170 eb = path->nodes[0];
5171 slot = path->slots[0];
5172 btrfs_item_key_to_cpu(eb, &found_key, slot);
5173 if (found_key.objectid != key.objectid ||
5174 found_key.type != key.type) {
57cfd462
JB		 5175 /* If we're a hole then just pretend nothing changed */
5176 ret = (left_disknr) ? 0 : 1;
31db9f7c
AB		 5177 goto out;
5178 }
5179
5180 /*
5181 * We're now on 2a, 2b or 7.
5182 */
5183 key = found_key;
5184 while (key.offset < ekey->offset + left_len) {
5185 ei = btrfs_item_ptr(eb, slot, struct btrfs_file_extent_item);
5186 right_type = btrfs_file_extent_type(eb, ei);
31db9f7c
AB		 5187 if (right_type != BTRFS_FILE_EXTENT_REG) {
5188 ret = 0;
5189 goto out;
5190 }
5191
007d31f7
JB		 5192 right_disknr = btrfs_file_extent_disk_bytenr(eb, ei);
5193 right_len = btrfs_file_extent_num_bytes(eb, ei);
5194 right_offset = btrfs_file_extent_offset(eb, ei);
5195 right_gen = btrfs_file_extent_generation(eb, ei);
5196
31db9f7c
AB		 5197 /*
5198 * Are we at extent 8? If yes, we know the extent is changed.
5199 * This may only happen on the first iteration.
5200 */
d8347fa4 5201 if (found_key.offset + right_len <= ekey->offset) {
57cfd462
JB		 5202 /* If we're a hole just pretend nothing changed */
5203 ret = (left_disknr) ? 0 : 1;
31db9f7c
AB		 5204 goto out;
5205 }
5206
5207 left_offset_fixed = left_offset;
5208 if (key.offset < ekey->offset) {
5209 /* Fix the right offset for 2a and 7. */
5210 right_offset += ekey->offset - key.offset;
5211 } else {
5212 /* Fix the left offset for all behind 2a and 2b */
5213 left_offset_fixed += key.offset - ekey->offset;
5214 }
5215
5216 /*
5217 * Check if we have the same extent.
5218 */
3954096d 5219 if (left_disknr != right_disknr ||
74dd17fb
CM		 5220 left_offset_fixed != right_offset ||
5221 left_gen != right_gen) {
31db9f7c
AB		 5222 ret = 0;
5223 goto out;
5224 }
5225
5226 /*
5227 * Go to the next extent.
5228 */
5229 ret = btrfs_next_item(sctx->parent_root, path);
5230 if (ret < 0)
5231 goto out;
5232 if (!ret) {
5233 eb = path->nodes[0];
5234 slot = path->slots[0];
5235 btrfs_item_key_to_cpu(eb, &found_key, slot);
5236 }
5237 if (ret || found_key.objectid != key.objectid ||
5238 found_key.type != key.type) {
5239 key.offset += right_len;
5240 break;
adaa4b8e
JS		 5241 }
5242 if (found_key.offset != key.offset + right_len) {
5243 ret = 0;
5244 goto out;
31db9f7c
AB		 5245 }
5246 key = found_key;
5247 }
5248
5249 /*
5250 * We're now behind the left extent (treat as unchanged) or at the end
5251 * of the right side (treat as changed).
5252 */
5253 if (key.offset >= ekey->offset + left_len)
5254 ret = 1;
5255 else
5256 ret = 0;
5257
5258
5259out:
5260 btrfs_free_path(path);
5261 return ret;
5262}
5263
16e7549f
JB		 5264static int get_last_extent(struct send_ctx *sctx, u64 offset)
5265{
5266 struct btrfs_path *path;
5267 struct btrfs_root *root = sctx->send_root;
5268 struct btrfs_file_extent_item *fi;
5269 struct btrfs_key key;
5270 u64 extent_end;
5271 u8 type;
5272 int ret;
5273
5274 path = alloc_path_for_send();
5275 if (!path)
5276 return -ENOMEM;
5277
5278 sctx->cur_inode_last_extent = 0;
5279
5280 key.objectid = sctx->cur_ino;
5281 key.type = BTRFS_EXTENT_DATA_KEY;
5282 key.offset = offset;
5283 ret = btrfs_search_slot_for_read(root, &key, path, 0, 1);
5284 if (ret < 0)
5285 goto out;
5286 ret = 0;
5287 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
5288 if (key.objectid != sctx->cur_ino || key.type != BTRFS_EXTENT_DATA_KEY)
5289 goto out;
5290
5291 fi = btrfs_item_ptr(path->nodes[0], path->slots[0],
5292 struct btrfs_file_extent_item);
5293 type = btrfs_file_extent_type(path->nodes[0], fi);
5294 if (type == BTRFS_FILE_EXTENT_INLINE) {
514ac8ad
CM		 5295 u64 size = btrfs_file_extent_inline_len(path->nodes[0],
5296 path->slots[0], fi);
16e7549f 5297 extent_end = ALIGN(key.offset + size,
da17066c 5298 sctx->send_root->fs_info->sectorsize);
16e7549f
JB		 5299 } else {
5300 extent_end = key.offset +
5301 btrfs_file_extent_num_bytes(path->nodes[0], fi);
5302 }
5303 sctx->cur_inode_last_extent = extent_end;
5304out:
5305 btrfs_free_path(path);
5306 return ret;
5307}
5308
82bfb2e7
FM		 5309static int range_is_hole_in_parent(struct send_ctx *sctx,
5310 const u64 start,
5311 const u64 end)
5312{
5313 struct btrfs_path *path;
5314 struct btrfs_key key;
5315 struct btrfs_root *root = sctx->parent_root;
5316 u64 search_start = start;
5317 int ret;
5318
5319 path = alloc_path_for_send();
5320 if (!path)
5321 return -ENOMEM;
5322
5323 key.objectid = sctx->cur_ino;
5324 key.type = BTRFS_EXTENT_DATA_KEY;
5325 key.offset = search_start;
5326 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
5327 if (ret < 0)
5328 goto out;
5329 if (ret > 0 && path->slots[0] > 0)
5330 path->slots[0]--;
5331
5332 while (search_start < end) {
5333 struct extent_buffer *leaf = path->nodes[0];
5334 int slot = path->slots[0];
5335 struct btrfs_file_extent_item *fi;
5336 u64 extent_end;
5337
5338 if (slot >= btrfs_header_nritems(leaf)) {
5339 ret = btrfs_next_leaf(root, path);
5340 if (ret < 0)
5341 goto out;
5342 else if (ret > 0)
5343 break;
5344 continue;
5345 }
5346
5347 btrfs_item_key_to_cpu(leaf, &key, slot);
5348 if (key.objectid < sctx->cur_ino ||
5349 key.type < BTRFS_EXTENT_DATA_KEY)
5350 goto next;
5351 if (key.objectid > sctx->cur_ino ||
5352 key.type > BTRFS_EXTENT_DATA_KEY ||
5353 key.offset >= end)
5354 break;
5355
5356 fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
5357 if (btrfs_file_extent_type(leaf, fi) ==
5358 BTRFS_FILE_EXTENT_INLINE) {
5359 u64 size = btrfs_file_extent_inline_len(leaf, slot, fi);
5360
5361 extent_end = ALIGN(key.offset + size,
5362 root->fs_info->sectorsize);
5363 } else {
5364 extent_end = key.offset +
5365 btrfs_file_extent_num_bytes(leaf, fi);
5366 }
5367 if (extent_end <= start)
5368 goto next;
5369 if (btrfs_file_extent_disk_bytenr(leaf, fi) == 0) {
5370 search_start = extent_end;
5371 goto next;
5372 }
5373 ret = 0;
5374 goto out;
5375next:
5376 path->slots[0]++;
5377 }
5378 ret = 1;
5379out:
5380 btrfs_free_path(path);
5381 return ret;
5382}
5383
16e7549f
JB		 5384static int maybe_send_hole(struct send_ctx *sctx, struct btrfs_path *path,
5385 struct btrfs_key *key)
5386{
5387 struct btrfs_file_extent_item *fi;
5388 u64 extent_end;
5389 u8 type;
5390 int ret = 0;
5391
5392 if (sctx->cur_ino != key->objectid || !need_send_hole(sctx))
5393 return 0;
5394
5395 if (sctx->cur_inode_last_extent == (u64)-1) {
5396 ret = get_last_extent(sctx, key->offset - 1);
5397 if (ret)
5398 return ret;
5399 }
5400
5401 fi = btrfs_item_ptr(path->nodes[0], path->slots[0],
5402 struct btrfs_file_extent_item);
5403 type = btrfs_file_extent_type(path->nodes[0], fi);
5404 if (type == BTRFS_FILE_EXTENT_INLINE) {
514ac8ad
CM		 5405 u64 size = btrfs_file_extent_inline_len(path->nodes[0],
5406 path->slots[0], fi);
16e7549f 5407 extent_end = ALIGN(key->offset + size,
da17066c 5408 sctx->send_root->fs_info->sectorsize);
16e7549f
JB		 5409 } else {
5410 extent_end = key->offset +
5411 btrfs_file_extent_num_bytes(path->nodes[0], fi);
5412 }
bf54f412
FDBM		 5413
5414 if (path->slots[0] == 0 &&
5415 sctx->cur_inode_last_extent < key->offset) {
5416 /*
5417 * We might have skipped entire leafs that contained only
5418 * file extent items for our current inode. These leafs have
5419 * a generation number smaller (older) than the one in the
5420 * current leaf and the leaf our last extent came from, and
5421 * are located between these 2 leafs.
5422 */
5423 ret = get_last_extent(sctx, key->offset - 1);
5424 if (ret)
5425 return ret;
5426 }
5427
82bfb2e7
FM		 5428 if (sctx->cur_inode_last_extent < key->offset) {
5429 ret = range_is_hole_in_parent(sctx,
5430 sctx->cur_inode_last_extent,
5431 key->offset);
5432 if (ret < 0)
5433 return ret;
5434 else if (ret == 0)
5435 ret = send_hole(sctx, key->offset);
5436 else
5437 ret = 0;
5438 }
16e7549f
JB		 5439 sctx->cur_inode_last_extent = extent_end;
5440 return ret;
5441}
5442
31db9f7c
AB		 5443static int process_extent(struct send_ctx *sctx,
5444 struct btrfs_path *path,
5445 struct btrfs_key *key)
5446{
31db9f7c 5447 struct clone_root *found_clone = NULL;
57cfd462 5448 int ret = 0;
31db9f7c
AB		 5449
5450 if (S_ISLNK(sctx->cur_inode_mode))
5451 return 0;
5452
5453 if (sctx->parent_root && !sctx->cur_inode_new) {
5454 ret = is_extent_unchanged(sctx, path, key);
5455 if (ret < 0)
5456 goto out;
5457 if (ret) {
5458 ret = 0;
16e7549f 5459 goto out_hole;
31db9f7c 5460 }
57cfd462
JB		 5461 } else {
5462 struct btrfs_file_extent_item *ei;
5463 u8 type;
5464
5465 ei = btrfs_item_ptr(path->nodes[0], path->slots[0],
5466 struct btrfs_file_extent_item);
5467 type = btrfs_file_extent_type(path->nodes[0], ei);
5468 if (type == BTRFS_FILE_EXTENT_PREALLOC ||
5469 type == BTRFS_FILE_EXTENT_REG) {
5470 /*
5471 * The send spec does not have a prealloc command yet,
5472 * so just leave a hole for prealloc'ed extents until
5473 * we have enough commands queued up to justify rev'ing
5474 * the send spec.
5475 */
5476 if (type == BTRFS_FILE_EXTENT_PREALLOC) {
5477 ret = 0;
5478 goto out;
5479 }
5480
5481 /* Have a hole, just skip it. */
5482 if (btrfs_file_extent_disk_bytenr(path->nodes[0], ei) == 0) {
5483 ret = 0;
5484 goto out;
5485 }
5486 }
31db9f7c
AB		 5487 }
5488
5489 ret = find_extent_clone(sctx, path, key->objectid, key->offset,
5490 sctx->cur_inode_size, &found_clone);
5491 if (ret != -ENOENT && ret < 0)
5492 goto out;
5493
5494 ret = send_write_or_clone(sctx, path, key, found_clone);
16e7549f
JB		 5495 if (ret)
5496 goto out;
5497out_hole:
5498 ret = maybe_send_hole(sctx, path, key);
31db9f7c
AB		 5499out:
5500 return ret;
5501}
5502
5503static int process_all_extents(struct send_ctx *sctx)
5504{
5505 int ret;
5506 struct btrfs_root *root;
5507 struct btrfs_path *path;
5508 struct btrfs_key key;
5509 struct btrfs_key found_key;
5510 struct extent_buffer *eb;
5511 int slot;
5512
5513 root = sctx->send_root;
5514 path = alloc_path_for_send();
5515 if (!path)
5516 return -ENOMEM;
5517
5518 key.objectid = sctx->cmp_key->objectid;
5519 key.type = BTRFS_EXTENT_DATA_KEY;
5520 key.offset = 0;
7fdd29d0
FDBM		 5521 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
5522 if (ret < 0)
5523 goto out;
31db9f7c 5524
7fdd29d0 5525 while (1) {
31db9f7c
AB		 5526 eb = path->nodes[0];
5527 slot = path->slots[0];
7fdd29d0
FDBM		 5528
5529 if (slot >= btrfs_header_nritems(eb)) {
5530 ret = btrfs_next_leaf(root, path);
5531 if (ret < 0) {
5532 goto out;
5533 } else if (ret > 0) {
5534 ret = 0;
5535 break;
5536 }
5537 continue;
5538 }
5539
31db9f7c
AB		 5540 btrfs_item_key_to_cpu(eb, &found_key, slot);
5541
5542 if (found_key.objectid != key.objectid ||
5543 found_key.type != key.type) {
5544 ret = 0;
5545 goto out;
5546 }
5547
5548 ret = process_extent(sctx, path, &found_key);
5549 if (ret < 0)
5550 goto out;
5551
7fdd29d0 5552 path->slots[0]++;
31db9f7c
AB		 5553 }
5554
5555out:
5556 btrfs_free_path(path);
5557 return ret;
5558}
5559
9f03740a
FDBM		 5560static int process_recorded_refs_if_needed(struct send_ctx *sctx, int at_end,
5561 int *pending_move,
5562 int *refs_processed)
31db9f7c
AB		 5563{
5564 int ret = 0;
5565
5566 if (sctx->cur_ino == 0)
5567 goto out;
5568 if (!at_end && sctx->cur_ino == sctx->cmp_key->objectid &&
96b5bd77 5569 sctx->cmp_key->type <= BTRFS_INODE_EXTREF_KEY)
31db9f7c
AB		 5570 goto out;
5571 if (list_empty(&sctx->new_refs) && list_empty(&sctx->deleted_refs))
5572 goto out;
5573
9f03740a 5574 ret = process_recorded_refs(sctx, pending_move);
e479d9bb
AB		 5575 if (ret < 0)
5576 goto out;
5577
9f03740a 5578 *refs_processed = 1;
31db9f7c
AB		 5579out:
5580 return ret;
5581}
5582
5583static int finish_inode_if_needed(struct send_ctx *sctx, int at_end)
5584{
5585 int ret = 0;
5586 u64 left_mode;
5587 u64 left_uid;
5588 u64 left_gid;
5589 u64 right_mode;
5590 u64 right_uid;
5591 u64 right_gid;
5592 int need_chmod = 0;
5593 int need_chown = 0;
9f03740a
FDBM		 5594 int pending_move = 0;
5595 int refs_processed = 0;
31db9f7c 5596
9f03740a
FDBM		 5597 ret = process_recorded_refs_if_needed(sctx, at_end, &pending_move,
5598 &refs_processed);
31db9f7c
AB		 5599 if (ret < 0)
5600 goto out;
5601
9f03740a
FDBM		 5602 /*
5603 * We have processed the refs and thus need to advance send_progress.
5604 * Now, calls to get_cur_xxx will take the updated refs of the current
5605 * inode into account.
5606 *
5607 * On the other hand, if our current inode is a directory and couldn't
5608 * be moved/renamed because its parent was renamed/moved too and it has
5609 * a higher inode number, we can only move/rename our current inode
5610 * after we moved/renamed its parent. Therefore in this case operate on
5611 * the old path (pre move/rename) of our current inode, and the
5612 * move/rename will be performed later.
5613 */
5614 if (refs_processed && !pending_move)
5615 sctx->send_progress = sctx->cur_ino + 1;
5616
31db9f7c
AB		 5617 if (sctx->cur_ino == 0 || sctx->cur_inode_deleted)
5618 goto out;
5619 if (!at_end && sctx->cmp_key->objectid == sctx->cur_ino)
5620 goto out;
5621
5622 ret = get_inode_info(sctx->send_root, sctx->cur_ino, NULL, NULL,
85a7b33b 5623 &left_mode, &left_uid, &left_gid, NULL);
31db9f7c
AB		 5624 if (ret < 0)
5625 goto out;
5626
e2d044fe
AL		 5627 if (!sctx->parent_root || sctx->cur_inode_new) {
5628 need_chown = 1;
5629 if (!S_ISLNK(sctx->cur_inode_mode))
31db9f7c 5630 need_chmod = 1;
e2d044fe
AL		 5631 } else {
5632 ret = get_inode_info(sctx->parent_root, sctx->cur_ino,
5633 NULL, NULL, &right_mode, &right_uid,
5634 &right_gid, NULL);
5635 if (ret < 0)
5636 goto out;
31db9f7c 5637
e2d044fe
AL		 5638 if (left_uid != right_uid || left_gid != right_gid)
5639 need_chown = 1;
5640 if (!S_ISLNK(sctx->cur_inode_mode) && left_mode != right_mode)
5641 need_chmod = 1;
31db9f7c
AB		 5642 }
5643
5644 if (S_ISREG(sctx->cur_inode_mode)) {
16e7549f 5645 if (need_send_hole(sctx)) {
766b5e5a
FM		 5646 if (sctx->cur_inode_last_extent == (u64)-1 ||
5647 sctx->cur_inode_last_extent <
5648 sctx->cur_inode_size) {
16e7549f
JB		 5649 ret = get_last_extent(sctx, (u64)-1);
5650 if (ret)
5651 goto out;
5652 }
5653 if (sctx->cur_inode_last_extent <
5654 sctx->cur_inode_size) {
5655 ret = send_hole(sctx, sctx->cur_inode_size);
5656 if (ret)
5657 goto out;
5658 }
5659 }
31db9f7c
AB		 5660 ret = send_truncate(sctx, sctx->cur_ino, sctx->cur_inode_gen,
5661 sctx->cur_inode_size);
5662 if (ret < 0)
5663 goto out;
5664 }
5665
5666 if (need_chown) {
5667 ret = send_chown(sctx, sctx->cur_ino, sctx->cur_inode_gen,
5668 left_uid, left_gid);
5669 if (ret < 0)
5670 goto out;
5671 }
5672 if (need_chmod) {
5673 ret = send_chmod(sctx, sctx->cur_ino, sctx->cur_inode_gen,
5674 left_mode);
5675 if (ret < 0)
5676 goto out;
5677 }
5678
5679 /*
9f03740a
FDBM		 5680 * If other directory inodes depended on our current directory
5681 * inode's move/rename, now do their move/rename operations.
31db9f7c 5682 */
9f03740a
FDBM		 5683 if (!is_waiting_for_move(sctx, sctx->cur_ino)) {
5684 ret = apply_children_dir_moves(sctx);
5685 if (ret)
5686 goto out;
fcbd2154
FM		 5687 /*
5688 * Need to send that every time, no matter if it actually
5689 * changed between the two trees as we have done changes to
5690 * the inode before. If our inode is a directory and it's
5691 * waiting to be moved/renamed, we will send its utimes when
5692 * it's moved/renamed, therefore we don't need to do it here.
5693 */
5694 sctx->send_progress = sctx->cur_ino + 1;
5695 ret = send_utimes(sctx, sctx->cur_ino, sctx->cur_inode_gen);
5696 if (ret < 0)
5697 goto out;
9f03740a
FDBM		 5698 }
5699
31db9f7c
AB		 5700out:
5701 return ret;
5702}
5703
5704static int changed_inode(struct send_ctx *sctx,
5705 enum btrfs_compare_tree_result result)
5706{
5707 int ret = 0;
5708 struct btrfs_key *key = sctx->cmp_key;
5709 struct btrfs_inode_item *left_ii = NULL;
5710 struct btrfs_inode_item *right_ii = NULL;
5711 u64 left_gen = 0;
5712 u64 right_gen = 0;
5713
31db9f7c
AB		 5714 sctx->cur_ino = key->objectid;
5715 sctx->cur_inode_new_gen = 0;
16e7549f 5716 sctx->cur_inode_last_extent = (u64)-1;
e479d9bb
AB		 5717
5718 /*
5719 * Set send_progress to current inode. This will tell all get_cur_xxx
5720 * functions that the current inode's refs are not updated yet. Later,
5721 * when process_recorded_refs is finished, it is set to cur_ino + 1.
5722 */
31db9f7c
AB		 5723 sctx->send_progress = sctx->cur_ino;
5724
5725 if (result == BTRFS_COMPARE_TREE_NEW ||
5726 result == BTRFS_COMPARE_TREE_CHANGED) {
5727 left_ii = btrfs_item_ptr(sctx->left_path->nodes[0],
5728 sctx->left_path->slots[0],
5729 struct btrfs_inode_item);
5730 left_gen = btrfs_inode_generation(sctx->left_path->nodes[0],
5731 left_ii);
5732 } else {
5733 right_ii = btrfs_item_ptr(sctx->right_path->nodes[0],
5734 sctx->right_path->slots[0],
5735 struct btrfs_inode_item);
5736 right_gen = btrfs_inode_generation(sctx->right_path->nodes[0],
5737 right_ii);
5738 }
5739 if (result == BTRFS_COMPARE_TREE_CHANGED) {
5740 right_ii = btrfs_item_ptr(sctx->right_path->nodes[0],
5741 sctx->right_path->slots[0],
5742 struct btrfs_inode_item);
5743
5744 right_gen = btrfs_inode_generation(sctx->right_path->nodes[0],
5745 right_ii);
6d85ed05
AB		 5746
5747 /*
5748 * The cur_ino = root dir case is special here. We can't treat
5749 * the inode as deleted+reused because it would generate a
5750 * stream that tries to delete/mkdir the root dir.
5751 */
5752 if (left_gen != right_gen &&
5753 sctx->cur_ino != BTRFS_FIRST_FREE_OBJECTID)
31db9f7c
AB		 5754 sctx->cur_inode_new_gen = 1;
5755 }
5756
5757 if (result == BTRFS_COMPARE_TREE_NEW) {
5758 sctx->cur_inode_gen = left_gen;
5759 sctx->cur_inode_new = 1;
5760 sctx->cur_inode_deleted = 0;
5761 sctx->cur_inode_size = btrfs_inode_size(
5762 sctx->left_path->nodes[0], left_ii);
5763 sctx->cur_inode_mode = btrfs_inode_mode(
5764 sctx->left_path->nodes[0], left_ii);
644d1940
LB		 5765 sctx->cur_inode_rdev = btrfs_inode_rdev(
5766 sctx->left_path->nodes[0], left_ii);
31db9f7c 5767 if (sctx->cur_ino != BTRFS_FIRST_FREE_OBJECTID)
1f4692da 5768 ret = send_create_inode_if_needed(sctx);
31db9f7c
AB		 5769 } else if (result == BTRFS_COMPARE_TREE_DELETED) {
5770 sctx->cur_inode_gen = right_gen;
5771 sctx->cur_inode_new = 0;
5772 sctx->cur_inode_deleted = 1;
5773 sctx->cur_inode_size = btrfs_inode_size(
5774 sctx->right_path->nodes[0], right_ii);
5775 sctx->cur_inode_mode = btrfs_inode_mode(
5776 sctx->right_path->nodes[0], right_ii);
5777 } else if (result == BTRFS_COMPARE_TREE_CHANGED) {
766702ef
AB		 5778 /*
5779 * We need to do some special handling in case the inode was
5780 * reported as changed with a changed generation number. This
5781 * means that the original inode was deleted and new inode
5782 * reused the same inum. So we have to treat the old inode as
5783 * deleted and the new one as new.
5784 */
31db9f7c 5785 if (sctx->cur_inode_new_gen) {
766702ef
AB		 5786 /*
5787 * First, process the inode as if it was deleted.
5788 */
31db9f7c
AB		 5789 sctx->cur_inode_gen = right_gen;
5790 sctx->cur_inode_new = 0;
5791 sctx->cur_inode_deleted = 1;
5792 sctx->cur_inode_size = btrfs_inode_size(
5793 sctx->right_path->nodes[0], right_ii);
5794 sctx->cur_inode_mode = btrfs_inode_mode(
5795 sctx->right_path->nodes[0], right_ii);
5796 ret = process_all_refs(sctx,
5797 BTRFS_COMPARE_TREE_DELETED);
5798 if (ret < 0)
5799 goto out;
5800
766702ef
AB		 5801 /*
5802 * Now process the inode as if it was new.
5803 */
31db9f7c
AB		 5804 sctx->cur_inode_gen = left_gen;
5805 sctx->cur_inode_new = 1;
5806 sctx->cur_inode_deleted = 0;
5807 sctx->cur_inode_size = btrfs_inode_size(
5808 sctx->left_path->nodes[0], left_ii);
5809 sctx->cur_inode_mode = btrfs_inode_mode(
5810 sctx->left_path->nodes[0], left_ii);
644d1940
LB		 5811 sctx->cur_inode_rdev = btrfs_inode_rdev(
5812 sctx->left_path->nodes[0], left_ii);
1f4692da 5813 ret = send_create_inode_if_needed(sctx);
31db9f7c
AB		 5814 if (ret < 0)
5815 goto out;
5816
5817 ret = process_all_refs(sctx, BTRFS_COMPARE_TREE_NEW);
5818 if (ret < 0)
5819 goto out;
e479d9bb
AB		 5820 /*
5821 * Advance send_progress now as we did not get into
5822 * process_recorded_refs_if_needed in the new_gen case.
5823 */
5824 sctx->send_progress = sctx->cur_ino + 1;
766702ef
AB		 5825
5826 /*
5827 * Now process all extents and xattrs of the inode as if
5828 * they were all new.
5829 */
31db9f7c
AB		 5830 ret = process_all_extents(sctx);
5831 if (ret < 0)
5832 goto out;
5833 ret = process_all_new_xattrs(sctx);
5834 if (ret < 0)
5835 goto out;
5836 } else {
5837 sctx->cur_inode_gen = left_gen;
5838 sctx->cur_inode_new = 0;
5839 sctx->cur_inode_new_gen = 0;
5840 sctx->cur_inode_deleted = 0;
5841 sctx->cur_inode_size = btrfs_inode_size(
5842 sctx->left_path->nodes[0], left_ii);
5843 sctx->cur_inode_mode = btrfs_inode_mode(
5844 sctx->left_path->nodes[0], left_ii);
5845 }
5846 }
5847
5848out:
5849 return ret;
5850}
5851
766702ef
AB		 5852/*
5853 * We have to process new refs before deleted refs, but compare_trees gives us
5854 * the new and deleted refs mixed. To fix this, we record the new/deleted refs
5855 * first and later process them in process_recorded_refs.
5856 * For the cur_inode_new_gen case, we skip recording completely because
5857 * changed_inode did already initiate processing of refs. The reason for this is
5858 * that in this case, compare_tree actually compares the refs of 2 different
5859 * inodes. To fix this, process_all_refs is used in changed_inode to handle all
5860 * refs of the right tree as deleted and all refs of the left tree as new.
5861 */
31db9f7c
AB		 5862static int changed_ref(struct send_ctx *sctx,
5863 enum btrfs_compare_tree_result result)
5864{
5865 int ret = 0;
5866
95155585
FM		 5867 if (sctx->cur_ino != sctx->cmp_key->objectid) {
5868 inconsistent_snapshot_error(sctx, result, "reference");
5869 return -EIO;
5870 }
31db9f7c
AB		 5871
5872 if (!sctx->cur_inode_new_gen &&
5873 sctx->cur_ino != BTRFS_FIRST_FREE_OBJECTID) {
5874 if (result == BTRFS_COMPARE_TREE_NEW)
5875 ret = record_new_ref(sctx);
5876 else if (result == BTRFS_COMPARE_TREE_DELETED)
5877 ret = record_deleted_ref(sctx);
5878 else if (result == BTRFS_COMPARE_TREE_CHANGED)
5879 ret = record_changed_ref(sctx);
5880 }
5881
5882 return ret;
5883}
5884
766702ef
AB		 5885/*
5886 * Process new/deleted/changed xattrs. We skip processing in the
5887 * cur_inode_new_gen case because changed_inode did already initiate processing
5888 * of xattrs. The reason is the same as in changed_ref
5889 */
31db9f7c
AB		 5890static int changed_xattr(struct send_ctx *sctx,
5891 enum btrfs_compare_tree_result result)
5892{
5893 int ret = 0;
5894
95155585
FM		 5895 if (sctx->cur_ino != sctx->cmp_key->objectid) {
5896 inconsistent_snapshot_error(sctx, result, "xattr");
5897 return -EIO;
5898 }
31db9f7c
AB		 5899
5900 if (!sctx->cur_inode_new_gen && !sctx->cur_inode_deleted) {
5901 if (result == BTRFS_COMPARE_TREE_NEW)
5902 ret = process_new_xattr(sctx);
5903 else if (result == BTRFS_COMPARE_TREE_DELETED)
5904 ret = process_deleted_xattr(sctx);
5905 else if (result == BTRFS_COMPARE_TREE_CHANGED)
5906 ret = process_changed_xattr(sctx);
5907 }
5908
5909 return ret;
5910}
5911
766702ef
AB		 5912/*
5913 * Process new/deleted/changed extents. We skip processing in the
5914 * cur_inode_new_gen case because changed_inode did already initiate processing
5915 * of extents. The reason is the same as in changed_ref
5916 */
31db9f7c
AB		 5917static int changed_extent(struct send_ctx *sctx,
5918 enum btrfs_compare_tree_result result)
5919{
5920 int ret = 0;
5921
95155585 5922 if (sctx->cur_ino != sctx->cmp_key->objectid) {
d5e84fd8
FM		 5923
5924 if (result == BTRFS_COMPARE_TREE_CHANGED) {
5925 struct extent_buffer *leaf_l;
5926 struct extent_buffer *leaf_r;
5927 struct btrfs_file_extent_item *ei_l;
5928 struct btrfs_file_extent_item *ei_r;
5929
5930 leaf_l = sctx->left_path->nodes[0];
5931 leaf_r = sctx->right_path->nodes[0];
5932 ei_l = btrfs_item_ptr(leaf_l,
5933 sctx->left_path->slots[0],
5934 struct btrfs_file_extent_item);
5935 ei_r = btrfs_item_ptr(leaf_r,
5936 sctx->right_path->slots[0],
5937 struct btrfs_file_extent_item);
5938
5939 /*
5940 * We may have found an extent item that has changed
5941 * only its disk_bytenr field and the corresponding
5942 * inode item was not updated. This case happens due to
5943 * very specific timings during relocation when a leaf
5944 * that contains file extent items is COWed while
5945 * relocation is ongoing and its in the stage where it
5946 * updates data pointers. So when this happens we can
5947 * safely ignore it since we know it's the same extent,
5948 * but just at different logical and physical locations
5949 * (when an extent is fully replaced with a new one, we
5950 * know the generation number must have changed too,
5951 * since snapshot creation implies committing the current
5952 * transaction, and the inode item must have been updated
5953 * as well).
5954 * This replacement of the disk_bytenr happens at
5955 * relocation.c:replace_file_extents() through
5956 * relocation.c:btrfs_reloc_cow_block().
5957 */
5958 if (btrfs_file_extent_generation(leaf_l, ei_l) ==
5959 btrfs_file_extent_generation(leaf_r, ei_r) &&
5960 btrfs_file_extent_ram_bytes(leaf_l, ei_l) ==
5961 btrfs_file_extent_ram_bytes(leaf_r, ei_r) &&
5962 btrfs_file_extent_compression(leaf_l, ei_l) ==
5963 btrfs_file_extent_compression(leaf_r, ei_r) &&
5964 btrfs_file_extent_encryption(leaf_l, ei_l) ==
5965 btrfs_file_extent_encryption(leaf_r, ei_r) &&
5966 btrfs_file_extent_other_encoding(leaf_l, ei_l) ==
5967 btrfs_file_extent_other_encoding(leaf_r, ei_r) &&
5968 btrfs_file_extent_type(leaf_l, ei_l) ==
5969 btrfs_file_extent_type(leaf_r, ei_r) &&
5970 btrfs_file_extent_disk_bytenr(leaf_l, ei_l) !=
5971 btrfs_file_extent_disk_bytenr(leaf_r, ei_r) &&
5972 btrfs_file_extent_disk_num_bytes(leaf_l, ei_l) ==
5973 btrfs_file_extent_disk_num_bytes(leaf_r, ei_r) &&
5974 btrfs_file_extent_offset(leaf_l, ei_l) ==
5975 btrfs_file_extent_offset(leaf_r, ei_r) &&
5976 btrfs_file_extent_num_bytes(leaf_l, ei_l) ==
5977 btrfs_file_extent_num_bytes(leaf_r, ei_r))
5978 return 0;
5979 }
5980
95155585
FM		 5981 inconsistent_snapshot_error(sctx, result, "extent");
5982 return -EIO;
5983 }
31db9f7c
AB		 5984
5985 if (!sctx->cur_inode_new_gen && !sctx->cur_inode_deleted) {
5986 if (result != BTRFS_COMPARE_TREE_DELETED)
5987 ret = process_extent(sctx, sctx->left_path,
5988 sctx->cmp_key);
5989 }
5990
5991 return ret;
5992}
5993
ba5e8f2e
JB		 5994static int dir_changed(struct send_ctx *sctx, u64 dir)
5995{
5996 u64 orig_gen, new_gen;
5997 int ret;
5998
5999 ret = get_inode_info(sctx->send_root, dir, NULL, &new_gen, NULL, NULL,
6000 NULL, NULL);
6001 if (ret)
6002 return ret;
6003
6004 ret = get_inode_info(sctx->parent_root, dir, NULL, &orig_gen, NULL,
6005 NULL, NULL, NULL);
6006 if (ret)
6007 return ret;
6008
6009 return (orig_gen != new_gen) ? 1 : 0;
6010}
6011
6012static int compare_refs(struct send_ctx *sctx, struct btrfs_path *path,
6013 struct btrfs_key *key)
6014{
6015 struct btrfs_inode_extref *extref;
6016 struct extent_buffer *leaf;
6017 u64 dirid = 0, last_dirid = 0;
6018 unsigned long ptr;
6019 u32 item_size;
6020 u32 cur_offset = 0;
6021 int ref_name_len;
6022 int ret = 0;
6023
6024 /* Easy case, just check this one dirid */
6025 if (key->type == BTRFS_INODE_REF_KEY) {
6026 dirid = key->offset;
6027
6028 ret = dir_changed(sctx, dirid);
6029 goto out;
6030 }
6031
6032 leaf = path->nodes[0];
6033 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
6034 ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
6035 while (cur_offset < item_size) {
6036 extref = (struct btrfs_inode_extref *)(ptr +
6037 cur_offset);
6038 dirid = btrfs_inode_extref_parent(leaf, extref);
6039 ref_name_len = btrfs_inode_extref_name_len(leaf, extref);
6040 cur_offset += ref_name_len + sizeof(*extref);
6041 if (dirid == last_dirid)
6042 continue;
6043 ret = dir_changed(sctx, dirid);
6044 if (ret)
6045 break;
6046 last_dirid = dirid;
6047 }
6048out:
6049 return ret;
6050}
6051
766702ef
AB		 6052/*
6053 * Updates compare related fields in sctx and simply forwards to the actual
6054 * changed_xxx functions.
6055 */
31db9f7c
AB		 6056static int changed_cb(struct btrfs_root *left_root,
6057 struct btrfs_root *right_root,
6058 struct btrfs_path *left_path,
6059 struct btrfs_path *right_path,
6060 struct btrfs_key *key,
6061 enum btrfs_compare_tree_result result,
6062 void *ctx)
6063{
6064 int ret = 0;
6065 struct send_ctx *sctx = ctx;
6066
ba5e8f2e 6067 if (result == BTRFS_COMPARE_TREE_SAME) {
16e7549f
JB		 6068 if (key->type == BTRFS_INODE_REF_KEY ||
6069 key->type == BTRFS_INODE_EXTREF_KEY) {
6070 ret = compare_refs(sctx, left_path, key);
6071 if (!ret)
6072 return 0;
6073 if (ret < 0)
6074 return ret;
6075 } else if (key->type == BTRFS_EXTENT_DATA_KEY) {
6076 return maybe_send_hole(sctx, left_path, key);
6077 } else {
ba5e8f2e 6078 return 0;
16e7549f 6079 }
ba5e8f2e
JB		 6080 result = BTRFS_COMPARE_TREE_CHANGED;
6081 ret = 0;
6082 }
6083
31db9f7c
AB		 6084 sctx->left_path = left_path;
6085 sctx->right_path = right_path;
6086 sctx->cmp_key = key;
6087
6088 ret = finish_inode_if_needed(sctx, 0);
6089 if (ret < 0)
6090 goto out;
6091
2981e225
AB		 6092 /* Ignore non-FS objects */
6093 if (key->objectid == BTRFS_FREE_INO_OBJECTID ||
6094 key->objectid == BTRFS_FREE_SPACE_OBJECTID)
6095 goto out;
6096
31db9f7c
AB		 6097 if (key->type == BTRFS_INODE_ITEM_KEY)
6098 ret = changed_inode(sctx, result);
96b5bd77
JS		 6099 else if (key->type == BTRFS_INODE_REF_KEY ||
6100 key->type == BTRFS_INODE_EXTREF_KEY)
31db9f7c
AB		 6101 ret = changed_ref(sctx, result);
6102 else if (key->type == BTRFS_XATTR_ITEM_KEY)
6103 ret = changed_xattr(sctx, result);
6104 else if (key->type == BTRFS_EXTENT_DATA_KEY)
6105 ret = changed_extent(sctx, result);
6106
6107out:
6108 return ret;
6109}
6110
6111static int full_send_tree(struct send_ctx *sctx)
6112{
6113 int ret;
31db9f7c
AB		 6114 struct btrfs_root *send_root = sctx->send_root;
6115 struct btrfs_key key;
6116 struct btrfs_key found_key;
6117 struct btrfs_path *path;
6118 struct extent_buffer *eb;
6119 int slot;
31db9f7c
AB		 6120
6121 path = alloc_path_for_send();
6122 if (!path)
6123 return -ENOMEM;
6124
31db9f7c
AB		 6125 key.objectid = BTRFS_FIRST_FREE_OBJECTID;
6126 key.type = BTRFS_INODE_ITEM_KEY;
6127 key.offset = 0;
6128
31db9f7c
AB		 6129 ret = btrfs_search_slot_for_read(send_root, &key, path, 1, 0);
6130 if (ret < 0)
6131 goto out;
6132 if (ret)
6133 goto out_finish;
6134
6135 while (1) {
31db9f7c
AB		 6136 eb = path->nodes[0];
6137 slot = path->slots[0];
6138 btrfs_item_key_to_cpu(eb, &found_key, slot);
6139
6140 ret = changed_cb(send_root, NULL, path, NULL,
6141 &found_key, BTRFS_COMPARE_TREE_NEW, sctx);
6142 if (ret < 0)
6143 goto out;
6144
6145 key.objectid = found_key.objectid;
6146 key.type = found_key.type;
6147 key.offset = found_key.offset + 1;
6148
6149 ret = btrfs_next_item(send_root, path);
6150 if (ret < 0)
6151 goto out;
6152 if (ret) {
6153 ret = 0;
6154 break;
6155 }
6156 }
6157
6158out_finish:
6159 ret = finish_inode_if_needed(sctx, 1);
6160
6161out:
6162 btrfs_free_path(path);
31db9f7c
AB		 6163 return ret;
6164}
6165
6166static int send_subvol(struct send_ctx *sctx)
6167{
6168 int ret;
6169
c2c71324
SB		 6170 if (!(sctx->flags & BTRFS_SEND_FLAG_OMIT_STREAM_HEADER)) {
6171 ret = send_header(sctx);
6172 if (ret < 0)
6173 goto out;
6174 }
31db9f7c
AB		 6175
6176 ret = send_subvol_begin(sctx);
6177 if (ret < 0)
6178 goto out;
6179
6180 if (sctx->parent_root) {
6181 ret = btrfs_compare_trees(sctx->send_root, sctx->parent_root,
6182 changed_cb, sctx);
6183 if (ret < 0)
6184 goto out;
6185 ret = finish_inode_if_needed(sctx, 1);
6186 if (ret < 0)
6187 goto out;
6188 } else {
6189 ret = full_send_tree(sctx);
6190 if (ret < 0)
6191 goto out;
6192 }
6193
6194out:
31db9f7c
AB		 6195 free_recorded_refs(sctx);
6196 return ret;
6197}
6198
e5fa8f86
FM		 6199/*
6200 * If orphan cleanup did remove any orphans from a root, it means the tree
6201 * was modified and therefore the commit root is not the same as the current
6202 * root anymore. This is a problem, because send uses the commit root and
6203 * therefore can see inode items that don't exist in the current root anymore,
6204 * and for example make calls to btrfs_iget, which will do tree lookups based
6205 * on the current root and not on the commit root. Those lookups will fail,
6206 * returning a -ESTALE error, and making send fail with that error. So make
6207 * sure a send does not see any orphans we have just removed, and that it will
6208 * see the same inodes regardless of whether a transaction commit happened
6209 * before it started (meaning that the commit root will be the same as the
6210 * current root) or not.
6211 */
6212static int ensure_commit_roots_uptodate(struct send_ctx *sctx)
6213{
6214 int i;
6215 struct btrfs_trans_handle *trans = NULL;
6216
6217again:
6218 if (sctx->parent_root &&
6219 sctx->parent_root->node != sctx->parent_root->commit_root)
6220 goto commit_trans;
6221
6222 for (i = 0; i < sctx->clone_roots_cnt; i++)
6223 if (sctx->clone_roots[i].root->node !=
6224 sctx->clone_roots[i].root->commit_root)
6225 goto commit_trans;
6226
6227 if (trans)
3a45bb20 6228 return btrfs_end_transaction(trans);
e5fa8f86
FM		 6229
6230 return 0;
6231
6232commit_trans:
6233 /* Use any root, all fs roots will get their commit roots updated. */
6234 if (!trans) {
6235 trans = btrfs_join_transaction(sctx->send_root);
6236 if (IS_ERR(trans))
6237 return PTR_ERR(trans);
6238 goto again;
6239 }
6240
3a45bb20 6241 return btrfs_commit_transaction(trans);
e5fa8f86
FM		 6242}
6243
66ef7d65
DS		 6244static void btrfs_root_dec_send_in_progress(struct btrfs_root* root)
6245{
6246 spin_lock(&root->root_item_lock);
6247 root->send_in_progress--;
6248 /*
6249 * Not much left to do, we don't know why it's unbalanced and
6250 * can't blindly reset it to 0.
6251 */
6252 if (root->send_in_progress < 0)
6253 btrfs_err(root->fs_info,
0b246afa
JM		 6254 "send_in_progres unbalanced %d root %llu",
6255 root->send_in_progress, root->root_key.objectid);
66ef7d65
DS		 6256 spin_unlock(&root->root_item_lock);
6257}
6258
31db9f7c
AB		 6259long btrfs_ioctl_send(struct file *mnt_file, void __user *arg_)
6260{
6261 int ret = 0;
0b246afa
JM		 6262 struct btrfs_root *send_root = BTRFS_I(file_inode(mnt_file))->root;
6263 struct btrfs_fs_info *fs_info = send_root->fs_info;
31db9f7c 6264 struct btrfs_root *clone_root;
31db9f7c
AB		 6265 struct btrfs_ioctl_send_args *arg = NULL;
6266 struct btrfs_key key;
31db9f7c
AB		 6267 struct send_ctx *sctx = NULL;
6268 u32 i;
6269 u64 *clone_sources_tmp = NULL;
2c686537 6270 int clone_sources_to_rollback = 0;
e55d1153 6271 unsigned alloc_size;
896c14f9 6272 int sort_clone_roots = 0;
18f687d5 6273 int index;
31db9f7c
AB		 6274
6275 if (!capable(CAP_SYS_ADMIN))
6276 return -EPERM;
6277
2c686537
DS		 6278 /*
6279 * The subvolume must remain read-only during send, protect against
521e0546 6280 * making it RW. This also protects against deletion.
2c686537
DS		 6281 */
6282 spin_lock(&send_root->root_item_lock);
6283 send_root->send_in_progress++;
6284 spin_unlock(&send_root->root_item_lock);
6285
139f807a
JB		 6286 /*
6287 * This is done when we lookup the root, it should already be complete
6288 * by the time we get here.
6289 */
6290 WARN_ON(send_root->orphan_cleanup_state != ORPHAN_CLEANUP_DONE);
6291
2c686537
DS		 6292 /*
6293 * Userspace tools do the checks and warn the user if it's
6294 * not RO.
6295 */
6296 if (!btrfs_root_readonly(send_root)) {
6297 ret = -EPERM;
6298 goto out;
6299 }
6300
31db9f7c
AB		 6301 arg = memdup_user(arg_, sizeof(*arg));
6302 if (IS_ERR(arg)) {
6303 ret = PTR_ERR(arg);
6304 arg = NULL;
6305 goto out;
6306 }
6307
f5ecec3c
DC		 6308 if (arg->clone_sources_count >
6309 ULLONG_MAX / sizeof(*arg->clone_sources)) {
6310 ret = -EINVAL;
6311 goto out;
6312 }
6313
31db9f7c 6314 if (!access_ok(VERIFY_READ, arg->clone_sources,
700ff4f0
DC		 6315 sizeof(*arg->clone_sources) *
6316 arg->clone_sources_count)) {
31db9f7c
AB		 6317 ret = -EFAULT;
6318 goto out;
6319 }
6320
c2c71324 6321 if (arg->flags & ~BTRFS_SEND_FLAG_MASK) {
cb95e7bf
MF		 6322 ret = -EINVAL;
6323 goto out;
6324 }
6325
e780b0d1 6326 sctx = kzalloc(sizeof(struct send_ctx), GFP_KERNEL);
31db9f7c
AB		 6327 if (!sctx) {
6328 ret = -ENOMEM;
6329 goto out;
6330 }
6331
6332 INIT_LIST_HEAD(&sctx->new_refs);
6333 INIT_LIST_HEAD(&sctx->deleted_refs);
e780b0d1 6334 INIT_RADIX_TREE(&sctx->name_cache, GFP_KERNEL);
31db9f7c
AB		 6335 INIT_LIST_HEAD(&sctx->name_cache_list);
6336
cb95e7bf
MF		 6337 sctx->flags = arg->flags;
6338
31db9f7c 6339 sctx->send_filp = fget(arg->send_fd);
ecc7ada7
TI		 6340 if (!sctx->send_filp) {
6341 ret = -EBADF;
31db9f7c
AB		 6342 goto out;
6343 }
6344
31db9f7c 6345 sctx->send_root = send_root;
521e0546
DS		 6346 /*
6347 * Unlikely but possible, if the subvolume is marked for deletion but
6348 * is slow to remove the directory entry, send can still be started
6349 */
6350 if (btrfs_root_dead(sctx->send_root)) {
6351 ret = -EPERM;
6352 goto out;
6353 }
6354
31db9f7c
AB		 6355 sctx->clone_roots_cnt = arg->clone_sources_count;
6356
6357 sctx->send_max_size = BTRFS_SEND_BUF_SIZE;
6ff48ce0 6358 sctx->send_buf = kmalloc(sctx->send_max_size, GFP_KERNEL | __GFP_NOWARN);
31db9f7c 6359 if (!sctx->send_buf) {
6ff48ce0
DS		 6360 sctx->send_buf = vmalloc(sctx->send_max_size);
6361 if (!sctx->send_buf) {
6362 ret = -ENOMEM;
6363 goto out;
6364 }
31db9f7c
AB		 6365 }
6366
eb5b75fe 6367 sctx->read_buf = kmalloc(BTRFS_SEND_READ_SIZE, GFP_KERNEL | __GFP_NOWARN);
31db9f7c 6368 if (!sctx->read_buf) {
eb5b75fe
DS		 6369 sctx->read_buf = vmalloc(BTRFS_SEND_READ_SIZE);
6370 if (!sctx->read_buf) {
6371 ret = -ENOMEM;
6372 goto out;
6373 }
31db9f7c
AB		 6374 }
6375
9f03740a
FDBM		 6376 sctx->pending_dir_moves = RB_ROOT;
6377 sctx->waiting_dir_moves = RB_ROOT;
9dc44214 6378 sctx->orphan_dirs = RB_ROOT;
9f03740a 6379
e55d1153
DS		 6380 alloc_size = sizeof(struct clone_root) * (arg->clone_sources_count + 1);
6381
c03d01f3 6382 sctx->clone_roots = kzalloc(alloc_size, GFP_KERNEL | __GFP_NOWARN);
31db9f7c 6383 if (!sctx->clone_roots) {
c03d01f3
DS		 6384 sctx->clone_roots = vzalloc(alloc_size);
6385 if (!sctx->clone_roots) {
6386 ret = -ENOMEM;
6387 goto out;
6388 }
31db9f7c
AB		 6389 }
6390
e55d1153
DS		 6391 alloc_size = arg->clone_sources_count * sizeof(*arg->clone_sources);
6392
31db9f7c 6393 if (arg->clone_sources_count) {
2f91306a 6394 clone_sources_tmp = kmalloc(alloc_size, GFP_KERNEL | __GFP_NOWARN);
31db9f7c 6395 if (!clone_sources_tmp) {
2f91306a
DS		 6396 clone_sources_tmp = vmalloc(alloc_size);
6397 if (!clone_sources_tmp) {
6398 ret = -ENOMEM;
6399 goto out;
6400 }
31db9f7c
AB		 6401 }
6402
6403 ret = copy_from_user(clone_sources_tmp, arg->clone_sources,
e55d1153 6404 alloc_size);
31db9f7c
AB		 6405 if (ret) {
6406 ret = -EFAULT;
6407 goto out;
6408 }
6409
6410 for (i = 0; i < arg->clone_sources_count; i++) {
6411 key.objectid = clone_sources_tmp[i];
6412 key.type = BTRFS_ROOT_ITEM_KEY;
6413 key.offset = (u64)-1;
18f687d5
WS		 6414
6415 index = srcu_read_lock(&fs_info->subvol_srcu);
6416
31db9f7c 6417 clone_root = btrfs_read_fs_root_no_name(fs_info, &key);
31db9f7c 6418 if (IS_ERR(clone_root)) {
18f687d5 6419 srcu_read_unlock(&fs_info->subvol_srcu, index);
31db9f7c
AB		 6420 ret = PTR_ERR(clone_root);
6421 goto out;
6422 }
2c686537 6423 spin_lock(&clone_root->root_item_lock);
5cc2b17e
FM		 6424 if (!btrfs_root_readonly(clone_root) ||
6425 btrfs_root_dead(clone_root)) {
2c686537 6426 spin_unlock(&clone_root->root_item_lock);
18f687d5 6427 srcu_read_unlock(&fs_info->subvol_srcu, index);
2c686537
DS		 6428 ret = -EPERM;
6429 goto out;
6430 }
2f1f465a 6431 clone_root->send_in_progress++;
2c686537 6432 spin_unlock(&clone_root->root_item_lock);
18f687d5
WS		 6433 srcu_read_unlock(&fs_info->subvol_srcu, index);
6434
31db9f7c 6435 sctx->clone_roots[i].root = clone_root;
2f1f465a 6436 clone_sources_to_rollback = i + 1;
31db9f7c 6437 }
2f91306a 6438 kvfree(clone_sources_tmp);
31db9f7c
AB		 6439 clone_sources_tmp = NULL;
6440 }
6441
6442 if (arg->parent_root) {
6443 key.objectid = arg->parent_root;
6444 key.type = BTRFS_ROOT_ITEM_KEY;
6445 key.offset = (u64)-1;
18f687d5
WS		 6446
6447 index = srcu_read_lock(&fs_info->subvol_srcu);
6448
31db9f7c 6449 sctx->parent_root = btrfs_read_fs_root_no_name(fs_info, &key);
b1b19596 6450 if (IS_ERR(sctx->parent_root)) {
18f687d5 6451 srcu_read_unlock(&fs_info->subvol_srcu, index);
b1b19596 6452 ret = PTR_ERR(sctx->parent_root);
31db9f7c
AB		 6453 goto out;
6454 }
18f687d5 6455
2c686537
DS		 6456 spin_lock(&sctx->parent_root->root_item_lock);
6457 sctx->parent_root->send_in_progress++;
521e0546
DS		 6458 if (!btrfs_root_readonly(sctx->parent_root) ||
6459 btrfs_root_dead(sctx->parent_root)) {
2c686537 6460 spin_unlock(&sctx->parent_root->root_item_lock);
18f687d5 6461 srcu_read_unlock(&fs_info->subvol_srcu, index);
2c686537
DS		 6462 ret = -EPERM;
6463 goto out;
6464 }
6465 spin_unlock(&sctx->parent_root->root_item_lock);
18f687d5
WS		 6466
6467 srcu_read_unlock(&fs_info->subvol_srcu, index);
31db9f7c
AB		 6468 }
6469
6470 /*
6471 * Clones from send_root are allowed, but only if the clone source
6472 * is behind the current send position. This is checked while searching
6473 * for possible clone sources.
6474 */
6475 sctx->clone_roots[sctx->clone_roots_cnt++].root = sctx->send_root;
6476
6477 /* We do a bsearch later */
6478 sort(sctx->clone_roots, sctx->clone_roots_cnt,
6479 sizeof(*sctx->clone_roots), __clone_root_cmp_sort,
6480 NULL);
896c14f9 6481 sort_clone_roots = 1;
31db9f7c 6482
e5fa8f86
FM		 6483 ret = ensure_commit_roots_uptodate(sctx);
6484 if (ret)
6485 goto out;
6486
2755a0de 6487 current->journal_info = BTRFS_SEND_TRANS_STUB;
31db9f7c 6488 ret = send_subvol(sctx);
a26e8c9f 6489 current->journal_info = NULL;
31db9f7c
AB		 6490 if (ret < 0)
6491 goto out;
6492
c2c71324
SB		 6493 if (!(sctx->flags & BTRFS_SEND_FLAG_OMIT_END_CMD)) {
6494 ret = begin_cmd(sctx, BTRFS_SEND_C_END);
6495 if (ret < 0)
6496 goto out;
6497 ret = send_cmd(sctx);
6498 if (ret < 0)
6499 goto out;
6500 }
31db9f7c
AB		 6501
6502out:
9f03740a
FDBM		 6503 WARN_ON(sctx && !ret && !RB_EMPTY_ROOT(&sctx->pending_dir_moves));
6504 while (sctx && !RB_EMPTY_ROOT(&sctx->pending_dir_moves)) {
6505 struct rb_node *n;
6506 struct pending_dir_move *pm;
6507
6508 n = rb_first(&sctx->pending_dir_moves);
6509 pm = rb_entry(n, struct pending_dir_move, node);
6510 while (!list_empty(&pm->list)) {
6511 struct pending_dir_move *pm2;
6512
6513 pm2 = list_first_entry(&pm->list,
6514 struct pending_dir_move, list);
6515 free_pending_move(sctx, pm2);
6516 }
6517 free_pending_move(sctx, pm);
6518 }
6519
6520 WARN_ON(sctx && !ret && !RB_EMPTY_ROOT(&sctx->waiting_dir_moves));
6521 while (sctx && !RB_EMPTY_ROOT(&sctx->waiting_dir_moves)) {
6522 struct rb_node *n;
6523 struct waiting_dir_move *dm;
6524
6525 n = rb_first(&sctx->waiting_dir_moves);
6526 dm = rb_entry(n, struct waiting_dir_move, node);
6527 rb_erase(&dm->node, &sctx->waiting_dir_moves);
6528 kfree(dm);
6529 }
6530
9dc44214
FM		 6531 WARN_ON(sctx && !ret && !RB_EMPTY_ROOT(&sctx->orphan_dirs));
6532 while (sctx && !RB_EMPTY_ROOT(&sctx->orphan_dirs)) {
6533 struct rb_node *n;
6534 struct orphan_dir_info *odi;
6535
6536 n = rb_first(&sctx->orphan_dirs);
6537 odi = rb_entry(n, struct orphan_dir_info, node);
6538 free_orphan_dir_info(sctx, odi);
6539 }
6540
896c14f9
WS		 6541 if (sort_clone_roots) {
6542 for (i = 0; i < sctx->clone_roots_cnt; i++)
6543 btrfs_root_dec_send_in_progress(
6544 sctx->clone_roots[i].root);
6545 } else {
6546 for (i = 0; sctx && i < clone_sources_to_rollback; i++)
6547 btrfs_root_dec_send_in_progress(
6548 sctx->clone_roots[i].root);
6549
6550 btrfs_root_dec_send_in_progress(send_root);
6551 }
66ef7d65
DS		 6552 if (sctx && !IS_ERR_OR_NULL(sctx->parent_root))
6553 btrfs_root_dec_send_in_progress(sctx->parent_root);
2c686537 6554
31db9f7c 6555 kfree(arg);
2f91306a 6556 kvfree(clone_sources_tmp);
31db9f7c
AB		 6557
6558 if (sctx) {
6559 if (sctx->send_filp)
6560 fput(sctx->send_filp);
6561
c03d01f3 6562 kvfree(sctx->clone_roots);
6ff48ce0 6563 kvfree(sctx->send_buf);
eb5b75fe 6564 kvfree(sctx->read_buf);
31db9f7c
AB		 6565
6566 name_cache_free(sctx);
6567
6568 kfree(sctx);
6569 }
6570
6571 return ret;
6572}
Linux 6.x block layer and io_uring tree(s)