blob: 945d1db98f26968ec051a6ff6116f971f18e7303 [file] [log] [blame]
Alexander Block31db9f72012-07-25 23:19:24 +02001/*
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>
27#include <linux/crc32c.h>
Stephen Rothwella1857eb2012-07-27 10:11:13 +100028#include <linux/vmalloc.h>
Andy Shevchenkoed848852013-08-21 10:32:13 +030029#include <linux/string.h>
Alexander Block31db9f72012-07-25 23:19:24 +020030
31#include "send.h"
32#include "backref.h"
33#include "locking.h"
34#include "disk-io.h"
35#include "btrfs_inode.h"
36#include "transaction.h"
37
38static int g_verbose = 0;
39
40#define verbose_printk(...) if (g_verbose) printk(__VA_ARGS__)
41
42/*
43 * A fs_path is a helper to dynamically build path names with unknown size.
44 * It reallocates the internal buffer on demand.
45 * It allows fast adding of path elements on the right side (normal path) and
46 * fast adding to the left side (reversed path). A reversed path can also be
47 * unreversed if needed.
48 */
49struct fs_path {
50 union {
51 struct {
52 char *start;
53 char *end;
54 char *prepared;
55
56 char *buf;
57 int buf_len;
Stefan Behrens35a36212013-08-14 18:12:25 +020058 unsigned int reversed:1;
59 unsigned int virtual_mem:1;
Alexander Block31db9f72012-07-25 23:19:24 +020060 char inline_buf[];
61 };
62 char pad[PAGE_SIZE];
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];
Mark Fashehcb95e7b2013-02-04 20:54:57 +000089 u64 flags; /* 'flags' member of btrfs_ioctl_send_args is u64 */
Alexander Block31db9f72012-07-25 23:19:24 +020090
91 struct vfsmount *mnt;
92
93 struct btrfs_root *send_root;
94 struct btrfs_root *parent_root;
95 struct clone_root *clone_roots;
96 int clone_roots_cnt;
97
98 /* current state of the compare_tree call */
99 struct btrfs_path *left_path;
100 struct btrfs_path *right_path;
101 struct btrfs_key *cmp_key;
102
103 /*
104 * infos of the currently processed inode. In case of deleted inodes,
105 * these are the values from the deleted inode.
106 */
107 u64 cur_ino;
108 u64 cur_inode_gen;
109 int cur_inode_new;
110 int cur_inode_new_gen;
111 int cur_inode_deleted;
Alexander Block31db9f72012-07-25 23:19:24 +0200112 u64 cur_inode_size;
113 u64 cur_inode_mode;
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
Alexander Block31db9f72012-07-25 23:19:24 +0200124 char *read_buf;
125};
126
127struct name_cache_entry {
128 struct list_head list;
Alexander Block7e0926f2012-07-28 14:20:58 +0200129 /*
130 * radix_tree has only 32bit entries but we need to handle 64bit inums.
131 * We use the lower 32bit of the 64bit inum to store it in the tree. If
132 * more then one inum would fall into the same entry, we use radix_list
133 * to store the additional entries. radix_list is also used to store
134 * entries where two entries have the same inum but different
135 * generations.
136 */
137 struct list_head radix_list;
Alexander Block31db9f72012-07-25 23:19:24 +0200138 u64 ino;
139 u64 gen;
140 u64 parent_ino;
141 u64 parent_gen;
142 int ret;
143 int need_later_update;
144 int name_len;
145 char name[];
146};
147
148static void fs_path_reset(struct fs_path *p)
149{
150 if (p->reversed) {
151 p->start = p->buf + p->buf_len - 1;
152 p->end = p->start;
153 *p->start = 0;
154 } else {
155 p->start = p->buf;
156 p->end = p->start;
157 *p->start = 0;
158 }
159}
160
Tsutomu Itoh924794c2013-05-08 07:51:52 +0000161static struct fs_path *fs_path_alloc(void)
Alexander Block31db9f72012-07-25 23:19:24 +0200162{
163 struct fs_path *p;
164
165 p = kmalloc(sizeof(*p), GFP_NOFS);
166 if (!p)
167 return NULL;
168 p->reversed = 0;
169 p->virtual_mem = 0;
170 p->buf = p->inline_buf;
171 p->buf_len = FS_PATH_INLINE_SIZE;
172 fs_path_reset(p);
173 return p;
174}
175
Tsutomu Itoh924794c2013-05-08 07:51:52 +0000176static struct fs_path *fs_path_alloc_reversed(void)
Alexander Block31db9f72012-07-25 23:19:24 +0200177{
178 struct fs_path *p;
179
Tsutomu Itoh924794c2013-05-08 07:51:52 +0000180 p = fs_path_alloc();
Alexander Block31db9f72012-07-25 23:19:24 +0200181 if (!p)
182 return NULL;
183 p->reversed = 1;
184 fs_path_reset(p);
185 return p;
186}
187
Tsutomu Itoh924794c2013-05-08 07:51:52 +0000188static void fs_path_free(struct fs_path *p)
Alexander Block31db9f72012-07-25 23:19:24 +0200189{
190 if (!p)
191 return;
192 if (p->buf != p->inline_buf) {
193 if (p->virtual_mem)
194 vfree(p->buf);
195 else
196 kfree(p->buf);
197 }
198 kfree(p);
199}
200
201static int fs_path_len(struct fs_path *p)
202{
203 return p->end - p->start;
204}
205
206static int fs_path_ensure_buf(struct fs_path *p, int len)
207{
208 char *tmp_buf;
209 int path_len;
210 int old_buf_len;
211
212 len++;
213
214 if (p->buf_len >= len)
215 return 0;
216
217 path_len = p->end - p->start;
218 old_buf_len = p->buf_len;
219 len = PAGE_ALIGN(len);
220
221 if (p->buf == p->inline_buf) {
Joe Perches8be04b92013-06-19 12:15:53 -0700222 tmp_buf = kmalloc(len, GFP_NOFS | __GFP_NOWARN);
Alexander Block31db9f72012-07-25 23:19:24 +0200223 if (!tmp_buf) {
224 tmp_buf = vmalloc(len);
225 if (!tmp_buf)
226 return -ENOMEM;
227 p->virtual_mem = 1;
228 }
229 memcpy(tmp_buf, p->buf, p->buf_len);
230 p->buf = tmp_buf;
231 p->buf_len = len;
232 } else {
233 if (p->virtual_mem) {
234 tmp_buf = vmalloc(len);
235 if (!tmp_buf)
236 return -ENOMEM;
237 memcpy(tmp_buf, p->buf, p->buf_len);
238 vfree(p->buf);
239 } else {
240 tmp_buf = krealloc(p->buf, len, GFP_NOFS);
241 if (!tmp_buf) {
242 tmp_buf = vmalloc(len);
243 if (!tmp_buf)
244 return -ENOMEM;
245 memcpy(tmp_buf, p->buf, p->buf_len);
246 kfree(p->buf);
247 p->virtual_mem = 1;
248 }
249 }
250 p->buf = tmp_buf;
251 p->buf_len = len;
252 }
253 if (p->reversed) {
254 tmp_buf = p->buf + old_buf_len - path_len - 1;
255 p->end = p->buf + p->buf_len - 1;
256 p->start = p->end - path_len;
257 memmove(p->start, tmp_buf, path_len + 1);
258 } else {
259 p->start = p->buf;
260 p->end = p->start + path_len;
261 }
262 return 0;
263}
264
265static int fs_path_prepare_for_add(struct fs_path *p, int name_len)
266{
267 int ret;
268 int new_len;
269
270 new_len = p->end - p->start + name_len;
271 if (p->start != p->end)
272 new_len++;
273 ret = fs_path_ensure_buf(p, new_len);
274 if (ret < 0)
275 goto out;
276
277 if (p->reversed) {
278 if (p->start != p->end)
279 *--p->start = '/';
280 p->start -= name_len;
281 p->prepared = p->start;
282 } else {
283 if (p->start != p->end)
284 *p->end++ = '/';
285 p->prepared = p->end;
286 p->end += name_len;
287 *p->end = 0;
288 }
289
290out:
291 return ret;
292}
293
294static int fs_path_add(struct fs_path *p, const char *name, int name_len)
295{
296 int ret;
297
298 ret = fs_path_prepare_for_add(p, name_len);
299 if (ret < 0)
300 goto out;
301 memcpy(p->prepared, name, name_len);
302 p->prepared = NULL;
303
304out:
305 return ret;
306}
307
308static int fs_path_add_path(struct fs_path *p, struct fs_path *p2)
309{
310 int ret;
311
312 ret = fs_path_prepare_for_add(p, p2->end - p2->start);
313 if (ret < 0)
314 goto out;
315 memcpy(p->prepared, p2->start, p2->end - p2->start);
316 p->prepared = NULL;
317
318out:
319 return ret;
320}
321
322static int fs_path_add_from_extent_buffer(struct fs_path *p,
323 struct extent_buffer *eb,
324 unsigned long off, int len)
325{
326 int ret;
327
328 ret = fs_path_prepare_for_add(p, len);
329 if (ret < 0)
330 goto out;
331
332 read_extent_buffer(eb, p->prepared, off, len);
333 p->prepared = NULL;
334
335out:
336 return ret;
337}
338
Alexander Block9ea3ef52012-07-28 11:08:09 +0200339#if 0
Alexander Block31db9f72012-07-25 23:19:24 +0200340static void fs_path_remove(struct fs_path *p)
341{
342 BUG_ON(p->reversed);
343 while (p->start != p->end && *p->end != '/')
344 p->end--;
345 *p->end = 0;
346}
Alexander Block9ea3ef52012-07-28 11:08:09 +0200347#endif
Alexander Block31db9f72012-07-25 23:19:24 +0200348
349static int fs_path_copy(struct fs_path *p, struct fs_path *from)
350{
351 int ret;
352
353 p->reversed = from->reversed;
354 fs_path_reset(p);
355
356 ret = fs_path_add_path(p, from);
357
358 return ret;
359}
360
361
362static void fs_path_unreverse(struct fs_path *p)
363{
364 char *tmp;
365 int len;
366
367 if (!p->reversed)
368 return;
369
370 tmp = p->start;
371 len = p->end - p->start;
372 p->start = p->buf;
373 p->end = p->start + len;
374 memmove(p->start, tmp, len + 1);
375 p->reversed = 0;
376}
377
378static struct btrfs_path *alloc_path_for_send(void)
379{
380 struct btrfs_path *path;
381
382 path = btrfs_alloc_path();
383 if (!path)
384 return NULL;
385 path->search_commit_root = 1;
386 path->skip_locking = 1;
387 return path;
388}
389
Eric Sandeen48a3b632013-04-25 20:41:01 +0000390static int write_buf(struct file *filp, const void *buf, u32 len, loff_t *off)
Alexander Block31db9f72012-07-25 23:19:24 +0200391{
392 int ret;
393 mm_segment_t old_fs;
394 u32 pos = 0;
395
396 old_fs = get_fs();
397 set_fs(KERNEL_DS);
398
399 while (pos < len) {
Anand Jain1bcea352012-09-14 00:04:21 -0600400 ret = vfs_write(filp, (char *)buf + pos, len - pos, off);
Alexander Block31db9f72012-07-25 23:19:24 +0200401 /* TODO handle that correctly */
402 /*if (ret == -ERESTARTSYS) {
403 continue;
404 }*/
405 if (ret < 0)
406 goto out;
407 if (ret == 0) {
408 ret = -EIO;
409 goto out;
410 }
411 pos += ret;
412 }
413
414 ret = 0;
415
416out:
417 set_fs(old_fs);
418 return ret;
419}
420
421static int tlv_put(struct send_ctx *sctx, u16 attr, const void *data, int len)
422{
423 struct btrfs_tlv_header *hdr;
424 int total_len = sizeof(*hdr) + len;
425 int left = sctx->send_max_size - sctx->send_size;
426
427 if (unlikely(left < total_len))
428 return -EOVERFLOW;
429
430 hdr = (struct btrfs_tlv_header *) (sctx->send_buf + sctx->send_size);
431 hdr->tlv_type = cpu_to_le16(attr);
432 hdr->tlv_len = cpu_to_le16(len);
433 memcpy(hdr + 1, data, len);
434 sctx->send_size += total_len;
435
436 return 0;
437}
438
439#if 0
440static int tlv_put_u8(struct send_ctx *sctx, u16 attr, u8 value)
441{
442 return tlv_put(sctx, attr, &value, sizeof(value));
443}
444
445static int tlv_put_u16(struct send_ctx *sctx, u16 attr, u16 value)
446{
447 __le16 tmp = cpu_to_le16(value);
448 return tlv_put(sctx, attr, &tmp, sizeof(tmp));
449}
450
451static int tlv_put_u32(struct send_ctx *sctx, u16 attr, u32 value)
452{
453 __le32 tmp = cpu_to_le32(value);
454 return tlv_put(sctx, attr, &tmp, sizeof(tmp));
455}
456#endif
457
458static int tlv_put_u64(struct send_ctx *sctx, u16 attr, u64 value)
459{
460 __le64 tmp = cpu_to_le64(value);
461 return tlv_put(sctx, attr, &tmp, sizeof(tmp));
462}
463
464static int tlv_put_string(struct send_ctx *sctx, u16 attr,
465 const char *str, int len)
466{
467 if (len == -1)
468 len = strlen(str);
469 return tlv_put(sctx, attr, str, len);
470}
471
472static int tlv_put_uuid(struct send_ctx *sctx, u16 attr,
473 const u8 *uuid)
474{
475 return tlv_put(sctx, attr, uuid, BTRFS_UUID_SIZE);
476}
477
478#if 0
479static int tlv_put_timespec(struct send_ctx *sctx, u16 attr,
480 struct timespec *ts)
481{
482 struct btrfs_timespec bts;
483 bts.sec = cpu_to_le64(ts->tv_sec);
484 bts.nsec = cpu_to_le32(ts->tv_nsec);
485 return tlv_put(sctx, attr, &bts, sizeof(bts));
486}
487#endif
488
489static int tlv_put_btrfs_timespec(struct send_ctx *sctx, u16 attr,
490 struct extent_buffer *eb,
491 struct btrfs_timespec *ts)
492{
493 struct btrfs_timespec bts;
494 read_extent_buffer(eb, &bts, (unsigned long)ts, sizeof(bts));
495 return tlv_put(sctx, attr, &bts, sizeof(bts));
496}
497
498
499#define TLV_PUT(sctx, attrtype, attrlen, data) \
500 do { \
501 ret = tlv_put(sctx, attrtype, attrlen, data); \
502 if (ret < 0) \
503 goto tlv_put_failure; \
504 } while (0)
505
506#define TLV_PUT_INT(sctx, attrtype, bits, value) \
507 do { \
508 ret = tlv_put_u##bits(sctx, attrtype, value); \
509 if (ret < 0) \
510 goto tlv_put_failure; \
511 } while (0)
512
513#define TLV_PUT_U8(sctx, attrtype, data) TLV_PUT_INT(sctx, attrtype, 8, data)
514#define TLV_PUT_U16(sctx, attrtype, data) TLV_PUT_INT(sctx, attrtype, 16, data)
515#define TLV_PUT_U32(sctx, attrtype, data) TLV_PUT_INT(sctx, attrtype, 32, data)
516#define TLV_PUT_U64(sctx, attrtype, data) TLV_PUT_INT(sctx, attrtype, 64, data)
517#define TLV_PUT_STRING(sctx, attrtype, str, len) \
518 do { \
519 ret = tlv_put_string(sctx, attrtype, str, len); \
520 if (ret < 0) \
521 goto tlv_put_failure; \
522 } while (0)
523#define TLV_PUT_PATH(sctx, attrtype, p) \
524 do { \
525 ret = tlv_put_string(sctx, attrtype, p->start, \
526 p->end - p->start); \
527 if (ret < 0) \
528 goto tlv_put_failure; \
529 } while(0)
530#define TLV_PUT_UUID(sctx, attrtype, uuid) \
531 do { \
532 ret = tlv_put_uuid(sctx, attrtype, uuid); \
533 if (ret < 0) \
534 goto tlv_put_failure; \
535 } while (0)
536#define TLV_PUT_TIMESPEC(sctx, attrtype, ts) \
537 do { \
538 ret = tlv_put_timespec(sctx, attrtype, ts); \
539 if (ret < 0) \
540 goto tlv_put_failure; \
541 } while (0)
542#define TLV_PUT_BTRFS_TIMESPEC(sctx, attrtype, eb, ts) \
543 do { \
544 ret = tlv_put_btrfs_timespec(sctx, attrtype, eb, ts); \
545 if (ret < 0) \
546 goto tlv_put_failure; \
547 } while (0)
548
549static int send_header(struct send_ctx *sctx)
550{
551 struct btrfs_stream_header hdr;
552
553 strcpy(hdr.magic, BTRFS_SEND_STREAM_MAGIC);
554 hdr.version = cpu_to_le32(BTRFS_SEND_STREAM_VERSION);
555
Anand Jain1bcea352012-09-14 00:04:21 -0600556 return write_buf(sctx->send_filp, &hdr, sizeof(hdr),
557 &sctx->send_off);
Alexander Block31db9f72012-07-25 23:19:24 +0200558}
559
560/*
561 * For each command/item we want to send to userspace, we call this function.
562 */
563static int begin_cmd(struct send_ctx *sctx, int cmd)
564{
565 struct btrfs_cmd_header *hdr;
566
Dulshani Gunawardhanafae7f212013-10-31 10:30:08 +0530567 if (WARN_ON(!sctx->send_buf))
Alexander Block31db9f72012-07-25 23:19:24 +0200568 return -EINVAL;
Alexander Block31db9f72012-07-25 23:19:24 +0200569
570 BUG_ON(sctx->send_size);
571
572 sctx->send_size += sizeof(*hdr);
573 hdr = (struct btrfs_cmd_header *)sctx->send_buf;
574 hdr->cmd = cpu_to_le16(cmd);
575
576 return 0;
577}
578
579static int send_cmd(struct send_ctx *sctx)
580{
581 int ret;
582 struct btrfs_cmd_header *hdr;
583 u32 crc;
584
585 hdr = (struct btrfs_cmd_header *)sctx->send_buf;
586 hdr->len = cpu_to_le32(sctx->send_size - sizeof(*hdr));
587 hdr->crc = 0;
588
589 crc = crc32c(0, (unsigned char *)sctx->send_buf, sctx->send_size);
590 hdr->crc = cpu_to_le32(crc);
591
Anand Jain1bcea352012-09-14 00:04:21 -0600592 ret = write_buf(sctx->send_filp, sctx->send_buf, sctx->send_size,
593 &sctx->send_off);
Alexander Block31db9f72012-07-25 23:19:24 +0200594
595 sctx->total_send_size += sctx->send_size;
596 sctx->cmd_send_size[le16_to_cpu(hdr->cmd)] += sctx->send_size;
597 sctx->send_size = 0;
598
599 return ret;
600}
601
602/*
603 * Sends a move instruction to user space
604 */
605static int send_rename(struct send_ctx *sctx,
606 struct fs_path *from, struct fs_path *to)
607{
608 int ret;
609
610verbose_printk("btrfs: send_rename %s -> %s\n", from->start, to->start);
611
612 ret = begin_cmd(sctx, BTRFS_SEND_C_RENAME);
613 if (ret < 0)
614 goto out;
615
616 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, from);
617 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH_TO, to);
618
619 ret = send_cmd(sctx);
620
621tlv_put_failure:
622out:
623 return ret;
624}
625
626/*
627 * Sends a link instruction to user space
628 */
629static int send_link(struct send_ctx *sctx,
630 struct fs_path *path, struct fs_path *lnk)
631{
632 int ret;
633
634verbose_printk("btrfs: send_link %s -> %s\n", path->start, lnk->start);
635
636 ret = begin_cmd(sctx, BTRFS_SEND_C_LINK);
637 if (ret < 0)
638 goto out;
639
640 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, path);
641 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH_LINK, lnk);
642
643 ret = send_cmd(sctx);
644
645tlv_put_failure:
646out:
647 return ret;
648}
649
650/*
651 * Sends an unlink instruction to user space
652 */
653static int send_unlink(struct send_ctx *sctx, struct fs_path *path)
654{
655 int ret;
656
657verbose_printk("btrfs: send_unlink %s\n", path->start);
658
659 ret = begin_cmd(sctx, BTRFS_SEND_C_UNLINK);
660 if (ret < 0)
661 goto out;
662
663 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, path);
664
665 ret = send_cmd(sctx);
666
667tlv_put_failure:
668out:
669 return ret;
670}
671
672/*
673 * Sends a rmdir instruction to user space
674 */
675static int send_rmdir(struct send_ctx *sctx, struct fs_path *path)
676{
677 int ret;
678
679verbose_printk("btrfs: send_rmdir %s\n", path->start);
680
681 ret = begin_cmd(sctx, BTRFS_SEND_C_RMDIR);
682 if (ret < 0)
683 goto out;
684
685 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, path);
686
687 ret = send_cmd(sctx);
688
689tlv_put_failure:
690out:
691 return ret;
692}
693
694/*
695 * Helper function to retrieve some fields from an inode item.
696 */
697static int get_inode_info(struct btrfs_root *root,
698 u64 ino, u64 *size, u64 *gen,
Alexander Block85a7b332012-07-26 23:39:10 +0200699 u64 *mode, u64 *uid, u64 *gid,
700 u64 *rdev)
Alexander Block31db9f72012-07-25 23:19:24 +0200701{
702 int ret;
703 struct btrfs_inode_item *ii;
704 struct btrfs_key key;
705 struct btrfs_path *path;
706
707 path = alloc_path_for_send();
708 if (!path)
709 return -ENOMEM;
710
711 key.objectid = ino;
712 key.type = BTRFS_INODE_ITEM_KEY;
713 key.offset = 0;
714 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
715 if (ret < 0)
716 goto out;
717 if (ret) {
718 ret = -ENOENT;
719 goto out;
720 }
721
722 ii = btrfs_item_ptr(path->nodes[0], path->slots[0],
723 struct btrfs_inode_item);
724 if (size)
725 *size = btrfs_inode_size(path->nodes[0], ii);
726 if (gen)
727 *gen = btrfs_inode_generation(path->nodes[0], ii);
728 if (mode)
729 *mode = btrfs_inode_mode(path->nodes[0], ii);
730 if (uid)
731 *uid = btrfs_inode_uid(path->nodes[0], ii);
732 if (gid)
733 *gid = btrfs_inode_gid(path->nodes[0], ii);
Alexander Block85a7b332012-07-26 23:39:10 +0200734 if (rdev)
735 *rdev = btrfs_inode_rdev(path->nodes[0], ii);
Alexander Block31db9f72012-07-25 23:19:24 +0200736
737out:
738 btrfs_free_path(path);
739 return ret;
740}
741
742typedef int (*iterate_inode_ref_t)(int num, u64 dir, int index,
743 struct fs_path *p,
744 void *ctx);
745
746/*
Jan Schmidt96b5bd72012-10-15 08:30:45 +0000747 * Helper function to iterate the entries in ONE btrfs_inode_ref or
748 * btrfs_inode_extref.
Alexander Block31db9f72012-07-25 23:19:24 +0200749 * The iterate callback may return a non zero value to stop iteration. This can
750 * be a negative value for error codes or 1 to simply stop it.
751 *
Jan Schmidt96b5bd72012-10-15 08:30:45 +0000752 * path must point to the INODE_REF or INODE_EXTREF when called.
Alexander Block31db9f72012-07-25 23:19:24 +0200753 */
Tsutomu Itoh924794c2013-05-08 07:51:52 +0000754static int iterate_inode_ref(struct btrfs_root *root, struct btrfs_path *path,
Alexander Block31db9f72012-07-25 23:19:24 +0200755 struct btrfs_key *found_key, int resolve,
756 iterate_inode_ref_t iterate, void *ctx)
757{
Jan Schmidt96b5bd72012-10-15 08:30:45 +0000758 struct extent_buffer *eb = path->nodes[0];
Alexander Block31db9f72012-07-25 23:19:24 +0200759 struct btrfs_item *item;
760 struct btrfs_inode_ref *iref;
Jan Schmidt96b5bd72012-10-15 08:30:45 +0000761 struct btrfs_inode_extref *extref;
Alexander Block31db9f72012-07-25 23:19:24 +0200762 struct btrfs_path *tmp_path;
763 struct fs_path *p;
Jan Schmidt96b5bd72012-10-15 08:30:45 +0000764 u32 cur = 0;
Alexander Block31db9f72012-07-25 23:19:24 +0200765 u32 total;
Jan Schmidt96b5bd72012-10-15 08:30:45 +0000766 int slot = path->slots[0];
Alexander Block31db9f72012-07-25 23:19:24 +0200767 u32 name_len;
768 char *start;
769 int ret = 0;
Jan Schmidt96b5bd72012-10-15 08:30:45 +0000770 int num = 0;
Alexander Block31db9f72012-07-25 23:19:24 +0200771 int index;
Jan Schmidt96b5bd72012-10-15 08:30:45 +0000772 u64 dir;
773 unsigned long name_off;
774 unsigned long elem_size;
775 unsigned long ptr;
Alexander Block31db9f72012-07-25 23:19:24 +0200776
Tsutomu Itoh924794c2013-05-08 07:51:52 +0000777 p = fs_path_alloc_reversed();
Alexander Block31db9f72012-07-25 23:19:24 +0200778 if (!p)
779 return -ENOMEM;
780
781 tmp_path = alloc_path_for_send();
782 if (!tmp_path) {
Tsutomu Itoh924794c2013-05-08 07:51:52 +0000783 fs_path_free(p);
Alexander Block31db9f72012-07-25 23:19:24 +0200784 return -ENOMEM;
785 }
786
Alexander Block31db9f72012-07-25 23:19:24 +0200787
Jan Schmidt96b5bd72012-10-15 08:30:45 +0000788 if (found_key->type == BTRFS_INODE_REF_KEY) {
789 ptr = (unsigned long)btrfs_item_ptr(eb, slot,
790 struct btrfs_inode_ref);
Ross Kirkdd3cc162013-09-16 15:58:09 +0100791 item = btrfs_item_nr(slot);
Jan Schmidt96b5bd72012-10-15 08:30:45 +0000792 total = btrfs_item_size(eb, item);
793 elem_size = sizeof(*iref);
794 } else {
795 ptr = btrfs_item_ptr_offset(eb, slot);
796 total = btrfs_item_size_nr(eb, slot);
797 elem_size = sizeof(*extref);
798 }
799
Alexander Block31db9f72012-07-25 23:19:24 +0200800 while (cur < total) {
801 fs_path_reset(p);
802
Jan Schmidt96b5bd72012-10-15 08:30:45 +0000803 if (found_key->type == BTRFS_INODE_REF_KEY) {
804 iref = (struct btrfs_inode_ref *)(ptr + cur);
805 name_len = btrfs_inode_ref_name_len(eb, iref);
806 name_off = (unsigned long)(iref + 1);
807 index = btrfs_inode_ref_index(eb, iref);
808 dir = found_key->offset;
809 } else {
810 extref = (struct btrfs_inode_extref *)(ptr + cur);
811 name_len = btrfs_inode_extref_name_len(eb, extref);
812 name_off = (unsigned long)&extref->name;
813 index = btrfs_inode_extref_index(eb, extref);
814 dir = btrfs_inode_extref_parent(eb, extref);
815 }
816
Alexander Block31db9f72012-07-25 23:19:24 +0200817 if (resolve) {
Jan Schmidt96b5bd72012-10-15 08:30:45 +0000818 start = btrfs_ref_to_path(root, tmp_path, name_len,
819 name_off, eb, dir,
820 p->buf, p->buf_len);
Alexander Block31db9f72012-07-25 23:19:24 +0200821 if (IS_ERR(start)) {
822 ret = PTR_ERR(start);
823 goto out;
824 }
825 if (start < p->buf) {
826 /* overflow , try again with larger buffer */
827 ret = fs_path_ensure_buf(p,
828 p->buf_len + p->buf - start);
829 if (ret < 0)
830 goto out;
Jan Schmidt96b5bd72012-10-15 08:30:45 +0000831 start = btrfs_ref_to_path(root, tmp_path,
832 name_len, name_off,
833 eb, dir,
834 p->buf, p->buf_len);
Alexander Block31db9f72012-07-25 23:19:24 +0200835 if (IS_ERR(start)) {
836 ret = PTR_ERR(start);
837 goto out;
838 }
839 BUG_ON(start < p->buf);
840 }
841 p->start = start;
842 } else {
Jan Schmidt96b5bd72012-10-15 08:30:45 +0000843 ret = fs_path_add_from_extent_buffer(p, eb, name_off,
844 name_len);
Alexander Block31db9f72012-07-25 23:19:24 +0200845 if (ret < 0)
846 goto out;
847 }
848
Jan Schmidt96b5bd72012-10-15 08:30:45 +0000849 cur += elem_size + name_len;
850 ret = iterate(num, dir, index, p, ctx);
Alexander Block31db9f72012-07-25 23:19:24 +0200851 if (ret)
852 goto out;
Alexander Block31db9f72012-07-25 23:19:24 +0200853 num++;
854 }
855
856out:
857 btrfs_free_path(tmp_path);
Tsutomu Itoh924794c2013-05-08 07:51:52 +0000858 fs_path_free(p);
Alexander Block31db9f72012-07-25 23:19:24 +0200859 return ret;
860}
861
862typedef int (*iterate_dir_item_t)(int num, struct btrfs_key *di_key,
863 const char *name, int name_len,
864 const char *data, int data_len,
865 u8 type, void *ctx);
866
867/*
868 * Helper function to iterate the entries in ONE btrfs_dir_item.
869 * The iterate callback may return a non zero value to stop iteration. This can
870 * be a negative value for error codes or 1 to simply stop it.
871 *
872 * path must point to the dir item when called.
873 */
Tsutomu Itoh924794c2013-05-08 07:51:52 +0000874static int iterate_dir_item(struct btrfs_root *root, struct btrfs_path *path,
Alexander Block31db9f72012-07-25 23:19:24 +0200875 struct btrfs_key *found_key,
876 iterate_dir_item_t iterate, void *ctx)
877{
878 int ret = 0;
879 struct extent_buffer *eb;
880 struct btrfs_item *item;
881 struct btrfs_dir_item *di;
Alexander Block31db9f72012-07-25 23:19:24 +0200882 struct btrfs_key di_key;
883 char *buf = NULL;
884 char *buf2 = NULL;
885 int buf_len;
886 int buf_virtual = 0;
887 u32 name_len;
888 u32 data_len;
889 u32 cur;
890 u32 len;
891 u32 total;
892 int slot;
893 int num;
894 u8 type;
895
896 buf_len = PAGE_SIZE;
897 buf = kmalloc(buf_len, GFP_NOFS);
898 if (!buf) {
899 ret = -ENOMEM;
900 goto out;
901 }
902
Alexander Block31db9f72012-07-25 23:19:24 +0200903 eb = path->nodes[0];
904 slot = path->slots[0];
Ross Kirkdd3cc162013-09-16 15:58:09 +0100905 item = btrfs_item_nr(slot);
Alexander Block31db9f72012-07-25 23:19:24 +0200906 di = btrfs_item_ptr(eb, slot, struct btrfs_dir_item);
907 cur = 0;
908 len = 0;
909 total = btrfs_item_size(eb, item);
910
911 num = 0;
912 while (cur < total) {
913 name_len = btrfs_dir_name_len(eb, di);
914 data_len = btrfs_dir_data_len(eb, di);
915 type = btrfs_dir_type(eb, di);
916 btrfs_dir_item_key_to_cpu(eb, di, &di_key);
917
918 if (name_len + data_len > buf_len) {
919 buf_len = PAGE_ALIGN(name_len + data_len);
920 if (buf_virtual) {
921 buf2 = vmalloc(buf_len);
922 if (!buf2) {
923 ret = -ENOMEM;
924 goto out;
925 }
926 vfree(buf);
927 } else {
928 buf2 = krealloc(buf, buf_len, GFP_NOFS);
929 if (!buf2) {
930 buf2 = vmalloc(buf_len);
931 if (!buf2) {
932 ret = -ENOMEM;
933 goto out;
934 }
935 kfree(buf);
936 buf_virtual = 1;
937 }
938 }
939
940 buf = buf2;
941 buf2 = NULL;
942 }
943
944 read_extent_buffer(eb, buf, (unsigned long)(di + 1),
945 name_len + data_len);
946
947 len = sizeof(*di) + name_len + data_len;
948 di = (struct btrfs_dir_item *)((char *)di + len);
949 cur += len;
950
951 ret = iterate(num, &di_key, buf, name_len, buf + name_len,
952 data_len, type, ctx);
953 if (ret < 0)
954 goto out;
955 if (ret) {
956 ret = 0;
957 goto out;
958 }
959
960 num++;
961 }
962
963out:
Alexander Block31db9f72012-07-25 23:19:24 +0200964 if (buf_virtual)
965 vfree(buf);
966 else
967 kfree(buf);
968 return ret;
969}
970
971static int __copy_first_ref(int num, u64 dir, int index,
972 struct fs_path *p, void *ctx)
973{
974 int ret;
975 struct fs_path *pt = ctx;
976
977 ret = fs_path_copy(pt, p);
978 if (ret < 0)
979 return ret;
980
981 /* we want the first only */
982 return 1;
983}
984
985/*
986 * Retrieve the first path of an inode. If an inode has more then one
987 * ref/hardlink, this is ignored.
988 */
Tsutomu Itoh924794c2013-05-08 07:51:52 +0000989static int get_inode_path(struct btrfs_root *root,
Alexander Block31db9f72012-07-25 23:19:24 +0200990 u64 ino, struct fs_path *path)
991{
992 int ret;
993 struct btrfs_key key, found_key;
994 struct btrfs_path *p;
995
996 p = alloc_path_for_send();
997 if (!p)
998 return -ENOMEM;
999
1000 fs_path_reset(path);
1001
1002 key.objectid = ino;
1003 key.type = BTRFS_INODE_REF_KEY;
1004 key.offset = 0;
1005
1006 ret = btrfs_search_slot_for_read(root, &key, p, 1, 0);
1007 if (ret < 0)
1008 goto out;
1009 if (ret) {
1010 ret = 1;
1011 goto out;
1012 }
1013 btrfs_item_key_to_cpu(p->nodes[0], &found_key, p->slots[0]);
1014 if (found_key.objectid != ino ||
Jan Schmidt96b5bd72012-10-15 08:30:45 +00001015 (found_key.type != BTRFS_INODE_REF_KEY &&
1016 found_key.type != BTRFS_INODE_EXTREF_KEY)) {
Alexander Block31db9f72012-07-25 23:19:24 +02001017 ret = -ENOENT;
1018 goto out;
1019 }
1020
Tsutomu Itoh924794c2013-05-08 07:51:52 +00001021 ret = iterate_inode_ref(root, p, &found_key, 1,
1022 __copy_first_ref, path);
Alexander Block31db9f72012-07-25 23:19:24 +02001023 if (ret < 0)
1024 goto out;
1025 ret = 0;
1026
1027out:
1028 btrfs_free_path(p);
1029 return ret;
1030}
1031
1032struct backref_ctx {
1033 struct send_ctx *sctx;
1034
1035 /* number of total found references */
1036 u64 found;
1037
1038 /*
1039 * used for clones found in send_root. clones found behind cur_objectid
1040 * and cur_offset are not considered as allowed clones.
1041 */
1042 u64 cur_objectid;
1043 u64 cur_offset;
1044
1045 /* may be truncated in case it's the last extent in a file */
1046 u64 extent_len;
1047
1048 /* Just to check for bugs in backref resolving */
Alexander Blockee849c02012-07-28 12:42:05 +02001049 int found_itself;
Alexander Block31db9f72012-07-25 23:19:24 +02001050};
1051
1052static int __clone_root_cmp_bsearch(const void *key, const void *elt)
1053{
Jan Schmidt995e01b2012-08-13 02:52:38 -06001054 u64 root = (u64)(uintptr_t)key;
Alexander Block31db9f72012-07-25 23:19:24 +02001055 struct clone_root *cr = (struct clone_root *)elt;
1056
1057 if (root < cr->root->objectid)
1058 return -1;
1059 if (root > cr->root->objectid)
1060 return 1;
1061 return 0;
1062}
1063
1064static int __clone_root_cmp_sort(const void *e1, const void *e2)
1065{
1066 struct clone_root *cr1 = (struct clone_root *)e1;
1067 struct clone_root *cr2 = (struct clone_root *)e2;
1068
1069 if (cr1->root->objectid < cr2->root->objectid)
1070 return -1;
1071 if (cr1->root->objectid > cr2->root->objectid)
1072 return 1;
1073 return 0;
1074}
1075
1076/*
1077 * Called for every backref that is found for the current extent.
Alexander Block766702e2012-07-28 14:11:31 +02001078 * Results are collected in sctx->clone_roots->ino/offset/found_refs
Alexander Block31db9f72012-07-25 23:19:24 +02001079 */
1080static int __iterate_backrefs(u64 ino, u64 offset, u64 root, void *ctx_)
1081{
1082 struct backref_ctx *bctx = ctx_;
1083 struct clone_root *found;
1084 int ret;
1085 u64 i_size;
1086
1087 /* First check if the root is in the list of accepted clone sources */
Jan Schmidt995e01b2012-08-13 02:52:38 -06001088 found = bsearch((void *)(uintptr_t)root, bctx->sctx->clone_roots,
Alexander Block31db9f72012-07-25 23:19:24 +02001089 bctx->sctx->clone_roots_cnt,
1090 sizeof(struct clone_root),
1091 __clone_root_cmp_bsearch);
1092 if (!found)
1093 return 0;
1094
1095 if (found->root == bctx->sctx->send_root &&
1096 ino == bctx->cur_objectid &&
1097 offset == bctx->cur_offset) {
Alexander Blockee849c02012-07-28 12:42:05 +02001098 bctx->found_itself = 1;
Alexander Block31db9f72012-07-25 23:19:24 +02001099 }
1100
1101 /*
Alexander Block766702e2012-07-28 14:11:31 +02001102 * There are inodes that have extents that lie behind its i_size. Don't
Alexander Block31db9f72012-07-25 23:19:24 +02001103 * accept clones from these extents.
1104 */
Alexander Block85a7b332012-07-26 23:39:10 +02001105 ret = get_inode_info(found->root, ino, &i_size, NULL, NULL, NULL, NULL,
1106 NULL);
Alexander Block31db9f72012-07-25 23:19:24 +02001107 if (ret < 0)
1108 return ret;
1109
1110 if (offset + bctx->extent_len > i_size)
1111 return 0;
1112
1113 /*
1114 * Make sure we don't consider clones from send_root that are
1115 * behind the current inode/offset.
1116 */
1117 if (found->root == bctx->sctx->send_root) {
1118 /*
1119 * TODO for the moment we don't accept clones from the inode
1120 * that is currently send. We may change this when
1121 * BTRFS_IOC_CLONE_RANGE supports cloning from and to the same
1122 * file.
1123 */
1124 if (ino >= bctx->cur_objectid)
1125 return 0;
Alexander Blocke938c8a2012-07-28 16:33:49 +02001126#if 0
1127 if (ino > bctx->cur_objectid)
Alexander Block31db9f72012-07-25 23:19:24 +02001128 return 0;
Alexander Blocke938c8a2012-07-28 16:33:49 +02001129 if (offset + bctx->extent_len > bctx->cur_offset)
1130 return 0;
1131#endif
Alexander Block31db9f72012-07-25 23:19:24 +02001132 }
1133
1134 bctx->found++;
1135 found->found_refs++;
1136 if (ino < found->ino) {
1137 found->ino = ino;
1138 found->offset = offset;
1139 } else if (found->ino == ino) {
1140 /*
1141 * same extent found more then once in the same file.
1142 */
1143 if (found->offset > offset + bctx->extent_len)
1144 found->offset = offset;
1145 }
1146
1147 return 0;
1148}
1149
1150/*
Alexander Block766702e2012-07-28 14:11:31 +02001151 * Given an inode, offset and extent item, it finds a good clone for a clone
1152 * instruction. Returns -ENOENT when none could be found. The function makes
1153 * sure that the returned clone is usable at the point where sending is at the
1154 * moment. This means, that no clones are accepted which lie behind the current
1155 * inode+offset.
1156 *
Alexander Block31db9f72012-07-25 23:19:24 +02001157 * path must point to the extent item when called.
1158 */
1159static int find_extent_clone(struct send_ctx *sctx,
1160 struct btrfs_path *path,
1161 u64 ino, u64 data_offset,
1162 u64 ino_size,
1163 struct clone_root **found)
1164{
1165 int ret;
1166 int extent_type;
1167 u64 logical;
Chris Mason74dd17f2012-08-07 16:25:13 -04001168 u64 disk_byte;
Alexander Block31db9f72012-07-25 23:19:24 +02001169 u64 num_bytes;
1170 u64 extent_item_pos;
Liu Bo69917e42012-09-07 20:01:28 -06001171 u64 flags = 0;
Alexander Block31db9f72012-07-25 23:19:24 +02001172 struct btrfs_file_extent_item *fi;
1173 struct extent_buffer *eb = path->nodes[0];
Alexander Block35075bb2012-07-28 12:44:34 +02001174 struct backref_ctx *backref_ctx = NULL;
Alexander Block31db9f72012-07-25 23:19:24 +02001175 struct clone_root *cur_clone_root;
1176 struct btrfs_key found_key;
1177 struct btrfs_path *tmp_path;
Chris Mason74dd17f2012-08-07 16:25:13 -04001178 int compressed;
Alexander Block31db9f72012-07-25 23:19:24 +02001179 u32 i;
1180
1181 tmp_path = alloc_path_for_send();
1182 if (!tmp_path)
1183 return -ENOMEM;
1184
Alexander Block35075bb2012-07-28 12:44:34 +02001185 backref_ctx = kmalloc(sizeof(*backref_ctx), GFP_NOFS);
1186 if (!backref_ctx) {
1187 ret = -ENOMEM;
1188 goto out;
1189 }
1190
Alexander Block31db9f72012-07-25 23:19:24 +02001191 if (data_offset >= ino_size) {
1192 /*
1193 * There may be extents that lie behind the file's size.
1194 * I at least had this in combination with snapshotting while
1195 * writing large files.
1196 */
1197 ret = 0;
1198 goto out;
1199 }
1200
1201 fi = btrfs_item_ptr(eb, path->slots[0],
1202 struct btrfs_file_extent_item);
1203 extent_type = btrfs_file_extent_type(eb, fi);
1204 if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
1205 ret = -ENOENT;
1206 goto out;
1207 }
Chris Mason74dd17f2012-08-07 16:25:13 -04001208 compressed = btrfs_file_extent_compression(eb, fi);
Alexander Block31db9f72012-07-25 23:19:24 +02001209
1210 num_bytes = btrfs_file_extent_num_bytes(eb, fi);
Chris Mason74dd17f2012-08-07 16:25:13 -04001211 disk_byte = btrfs_file_extent_disk_bytenr(eb, fi);
1212 if (disk_byte == 0) {
Alexander Block31db9f72012-07-25 23:19:24 +02001213 ret = -ENOENT;
1214 goto out;
1215 }
Chris Mason74dd17f2012-08-07 16:25:13 -04001216 logical = disk_byte + btrfs_file_extent_offset(eb, fi);
Alexander Block31db9f72012-07-25 23:19:24 +02001217
Liu Bo69917e42012-09-07 20:01:28 -06001218 ret = extent_from_logical(sctx->send_root->fs_info, disk_byte, tmp_path,
1219 &found_key, &flags);
Alexander Block31db9f72012-07-25 23:19:24 +02001220 btrfs_release_path(tmp_path);
1221
1222 if (ret < 0)
1223 goto out;
Liu Bo69917e42012-09-07 20:01:28 -06001224 if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
Alexander Block31db9f72012-07-25 23:19:24 +02001225 ret = -EIO;
1226 goto out;
1227 }
1228
1229 /*
1230 * Setup the clone roots.
1231 */
1232 for (i = 0; i < sctx->clone_roots_cnt; i++) {
1233 cur_clone_root = sctx->clone_roots + i;
1234 cur_clone_root->ino = (u64)-1;
1235 cur_clone_root->offset = 0;
1236 cur_clone_root->found_refs = 0;
1237 }
1238
Alexander Block35075bb2012-07-28 12:44:34 +02001239 backref_ctx->sctx = sctx;
1240 backref_ctx->found = 0;
1241 backref_ctx->cur_objectid = ino;
1242 backref_ctx->cur_offset = data_offset;
1243 backref_ctx->found_itself = 0;
1244 backref_ctx->extent_len = num_bytes;
Alexander Block31db9f72012-07-25 23:19:24 +02001245
1246 /*
1247 * The last extent of a file may be too large due to page alignment.
1248 * We need to adjust extent_len in this case so that the checks in
1249 * __iterate_backrefs work.
1250 */
1251 if (data_offset + num_bytes >= ino_size)
Alexander Block35075bb2012-07-28 12:44:34 +02001252 backref_ctx->extent_len = ino_size - data_offset;
Alexander Block31db9f72012-07-25 23:19:24 +02001253
1254 /*
1255 * Now collect all backrefs.
1256 */
Chris Mason74dd17f2012-08-07 16:25:13 -04001257 if (compressed == BTRFS_COMPRESS_NONE)
1258 extent_item_pos = logical - found_key.objectid;
1259 else
1260 extent_item_pos = 0;
1261
Alexander Block31db9f72012-07-25 23:19:24 +02001262 extent_item_pos = logical - found_key.objectid;
1263 ret = iterate_extent_inodes(sctx->send_root->fs_info,
1264 found_key.objectid, extent_item_pos, 1,
Alexander Block35075bb2012-07-28 12:44:34 +02001265 __iterate_backrefs, backref_ctx);
Chris Mason74dd17f2012-08-07 16:25:13 -04001266
Alexander Block31db9f72012-07-25 23:19:24 +02001267 if (ret < 0)
1268 goto out;
1269
Alexander Block35075bb2012-07-28 12:44:34 +02001270 if (!backref_ctx->found_itself) {
Alexander Block31db9f72012-07-25 23:19:24 +02001271 /* found a bug in backref code? */
1272 ret = -EIO;
1273 printk(KERN_ERR "btrfs: ERROR did not find backref in "
1274 "send_root. inode=%llu, offset=%llu, "
Chris Mason74dd17f2012-08-07 16:25:13 -04001275 "disk_byte=%llu found extent=%llu\n",
1276 ino, data_offset, disk_byte, found_key.objectid);
Alexander Block31db9f72012-07-25 23:19:24 +02001277 goto out;
1278 }
1279
1280verbose_printk(KERN_DEBUG "btrfs: find_extent_clone: data_offset=%llu, "
1281 "ino=%llu, "
1282 "num_bytes=%llu, logical=%llu\n",
1283 data_offset, ino, num_bytes, logical);
1284
Alexander Block35075bb2012-07-28 12:44:34 +02001285 if (!backref_ctx->found)
Alexander Block31db9f72012-07-25 23:19:24 +02001286 verbose_printk("btrfs: no clones found\n");
1287
1288 cur_clone_root = NULL;
1289 for (i = 0; i < sctx->clone_roots_cnt; i++) {
1290 if (sctx->clone_roots[i].found_refs) {
1291 if (!cur_clone_root)
1292 cur_clone_root = sctx->clone_roots + i;
1293 else if (sctx->clone_roots[i].root == sctx->send_root)
1294 /* prefer clones from send_root over others */
1295 cur_clone_root = sctx->clone_roots + i;
Alexander Block31db9f72012-07-25 23:19:24 +02001296 }
1297
1298 }
1299
1300 if (cur_clone_root) {
1301 *found = cur_clone_root;
1302 ret = 0;
1303 } else {
1304 ret = -ENOENT;
1305 }
1306
1307out:
1308 btrfs_free_path(tmp_path);
Alexander Block35075bb2012-07-28 12:44:34 +02001309 kfree(backref_ctx);
Alexander Block31db9f72012-07-25 23:19:24 +02001310 return ret;
1311}
1312
Tsutomu Itoh924794c2013-05-08 07:51:52 +00001313static int read_symlink(struct btrfs_root *root,
Alexander Block31db9f72012-07-25 23:19:24 +02001314 u64 ino,
1315 struct fs_path *dest)
1316{
1317 int ret;
1318 struct btrfs_path *path;
1319 struct btrfs_key key;
1320 struct btrfs_file_extent_item *ei;
1321 u8 type;
1322 u8 compression;
1323 unsigned long off;
1324 int len;
1325
1326 path = alloc_path_for_send();
1327 if (!path)
1328 return -ENOMEM;
1329
1330 key.objectid = ino;
1331 key.type = BTRFS_EXTENT_DATA_KEY;
1332 key.offset = 0;
1333 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1334 if (ret < 0)
1335 goto out;
1336 BUG_ON(ret);
1337
1338 ei = btrfs_item_ptr(path->nodes[0], path->slots[0],
1339 struct btrfs_file_extent_item);
1340 type = btrfs_file_extent_type(path->nodes[0], ei);
1341 compression = btrfs_file_extent_compression(path->nodes[0], ei);
1342 BUG_ON(type != BTRFS_FILE_EXTENT_INLINE);
1343 BUG_ON(compression);
1344
1345 off = btrfs_file_extent_inline_start(ei);
1346 len = btrfs_file_extent_inline_len(path->nodes[0], ei);
1347
1348 ret = fs_path_add_from_extent_buffer(dest, path->nodes[0], off, len);
Alexander Block31db9f72012-07-25 23:19:24 +02001349
1350out:
1351 btrfs_free_path(path);
1352 return ret;
1353}
1354
1355/*
1356 * Helper function to generate a file name that is unique in the root of
1357 * send_root and parent_root. This is used to generate names for orphan inodes.
1358 */
1359static int gen_unique_name(struct send_ctx *sctx,
1360 u64 ino, u64 gen,
1361 struct fs_path *dest)
1362{
1363 int ret = 0;
1364 struct btrfs_path *path;
1365 struct btrfs_dir_item *di;
1366 char tmp[64];
1367 int len;
1368 u64 idx = 0;
1369
1370 path = alloc_path_for_send();
1371 if (!path)
1372 return -ENOMEM;
1373
1374 while (1) {
1375 len = snprintf(tmp, sizeof(tmp) - 1, "o%llu-%llu-%llu",
1376 ino, gen, idx);
1377 if (len >= sizeof(tmp)) {
1378 /* should really not happen */
1379 ret = -EOVERFLOW;
1380 goto out;
1381 }
1382
1383 di = btrfs_lookup_dir_item(NULL, sctx->send_root,
1384 path, BTRFS_FIRST_FREE_OBJECTID,
1385 tmp, strlen(tmp), 0);
1386 btrfs_release_path(path);
1387 if (IS_ERR(di)) {
1388 ret = PTR_ERR(di);
1389 goto out;
1390 }
1391 if (di) {
1392 /* not unique, try again */
1393 idx++;
1394 continue;
1395 }
1396
1397 if (!sctx->parent_root) {
1398 /* unique */
1399 ret = 0;
1400 break;
1401 }
1402
1403 di = btrfs_lookup_dir_item(NULL, sctx->parent_root,
1404 path, BTRFS_FIRST_FREE_OBJECTID,
1405 tmp, strlen(tmp), 0);
1406 btrfs_release_path(path);
1407 if (IS_ERR(di)) {
1408 ret = PTR_ERR(di);
1409 goto out;
1410 }
1411 if (di) {
1412 /* not unique, try again */
1413 idx++;
1414 continue;
1415 }
1416 /* unique */
1417 break;
1418 }
1419
1420 ret = fs_path_add(dest, tmp, strlen(tmp));
1421
1422out:
1423 btrfs_free_path(path);
1424 return ret;
1425}
1426
1427enum inode_state {
1428 inode_state_no_change,
1429 inode_state_will_create,
1430 inode_state_did_create,
1431 inode_state_will_delete,
1432 inode_state_did_delete,
1433};
1434
1435static int get_cur_inode_state(struct send_ctx *sctx, u64 ino, u64 gen)
1436{
1437 int ret;
1438 int left_ret;
1439 int right_ret;
1440 u64 left_gen;
1441 u64 right_gen;
1442
1443 ret = get_inode_info(sctx->send_root, ino, NULL, &left_gen, NULL, NULL,
Alexander Block85a7b332012-07-26 23:39:10 +02001444 NULL, NULL);
Alexander Block31db9f72012-07-25 23:19:24 +02001445 if (ret < 0 && ret != -ENOENT)
1446 goto out;
1447 left_ret = ret;
1448
1449 if (!sctx->parent_root) {
1450 right_ret = -ENOENT;
1451 } else {
1452 ret = get_inode_info(sctx->parent_root, ino, NULL, &right_gen,
Alexander Block85a7b332012-07-26 23:39:10 +02001453 NULL, NULL, NULL, NULL);
Alexander Block31db9f72012-07-25 23:19:24 +02001454 if (ret < 0 && ret != -ENOENT)
1455 goto out;
1456 right_ret = ret;
1457 }
1458
1459 if (!left_ret && !right_ret) {
Alexander Blocke938c8a2012-07-28 16:33:49 +02001460 if (left_gen == gen && right_gen == gen) {
Alexander Block31db9f72012-07-25 23:19:24 +02001461 ret = inode_state_no_change;
Alexander Blocke938c8a2012-07-28 16:33:49 +02001462 } else if (left_gen == gen) {
Alexander Block31db9f72012-07-25 23:19:24 +02001463 if (ino < sctx->send_progress)
1464 ret = inode_state_did_create;
1465 else
1466 ret = inode_state_will_create;
1467 } else if (right_gen == gen) {
1468 if (ino < sctx->send_progress)
1469 ret = inode_state_did_delete;
1470 else
1471 ret = inode_state_will_delete;
1472 } else {
1473 ret = -ENOENT;
1474 }
1475 } else if (!left_ret) {
1476 if (left_gen == gen) {
1477 if (ino < sctx->send_progress)
1478 ret = inode_state_did_create;
1479 else
1480 ret = inode_state_will_create;
1481 } else {
1482 ret = -ENOENT;
1483 }
1484 } else if (!right_ret) {
1485 if (right_gen == gen) {
1486 if (ino < sctx->send_progress)
1487 ret = inode_state_did_delete;
1488 else
1489 ret = inode_state_will_delete;
1490 } else {
1491 ret = -ENOENT;
1492 }
1493 } else {
1494 ret = -ENOENT;
1495 }
1496
1497out:
1498 return ret;
1499}
1500
1501static int is_inode_existent(struct send_ctx *sctx, u64 ino, u64 gen)
1502{
1503 int ret;
1504
1505 ret = get_cur_inode_state(sctx, ino, gen);
1506 if (ret < 0)
1507 goto out;
1508
1509 if (ret == inode_state_no_change ||
1510 ret == inode_state_did_create ||
1511 ret == inode_state_will_delete)
1512 ret = 1;
1513 else
1514 ret = 0;
1515
1516out:
1517 return ret;
1518}
1519
1520/*
1521 * Helper function to lookup a dir item in a dir.
1522 */
1523static int lookup_dir_item_inode(struct btrfs_root *root,
1524 u64 dir, const char *name, int name_len,
1525 u64 *found_inode,
1526 u8 *found_type)
1527{
1528 int ret = 0;
1529 struct btrfs_dir_item *di;
1530 struct btrfs_key key;
1531 struct btrfs_path *path;
1532
1533 path = alloc_path_for_send();
1534 if (!path)
1535 return -ENOMEM;
1536
1537 di = btrfs_lookup_dir_item(NULL, root, path,
1538 dir, name, name_len, 0);
1539 if (!di) {
1540 ret = -ENOENT;
1541 goto out;
1542 }
1543 if (IS_ERR(di)) {
1544 ret = PTR_ERR(di);
1545 goto out;
1546 }
1547 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key);
1548 *found_inode = key.objectid;
1549 *found_type = btrfs_dir_type(path->nodes[0], di);
1550
1551out:
1552 btrfs_free_path(path);
1553 return ret;
1554}
1555
Alexander Block766702e2012-07-28 14:11:31 +02001556/*
1557 * Looks up the first btrfs_inode_ref of a given ino. It returns the parent dir,
1558 * generation of the parent dir and the name of the dir entry.
1559 */
Tsutomu Itoh924794c2013-05-08 07:51:52 +00001560static int get_first_ref(struct btrfs_root *root, u64 ino,
Alexander Block31db9f72012-07-25 23:19:24 +02001561 u64 *dir, u64 *dir_gen, struct fs_path *name)
1562{
1563 int ret;
1564 struct btrfs_key key;
1565 struct btrfs_key found_key;
1566 struct btrfs_path *path;
Alexander Block31db9f72012-07-25 23:19:24 +02001567 int len;
Jan Schmidt96b5bd72012-10-15 08:30:45 +00001568 u64 parent_dir;
Alexander Block31db9f72012-07-25 23:19:24 +02001569
1570 path = alloc_path_for_send();
1571 if (!path)
1572 return -ENOMEM;
1573
1574 key.objectid = ino;
1575 key.type = BTRFS_INODE_REF_KEY;
1576 key.offset = 0;
1577
1578 ret = btrfs_search_slot_for_read(root, &key, path, 1, 0);
1579 if (ret < 0)
1580 goto out;
1581 if (!ret)
1582 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1583 path->slots[0]);
Jan Schmidt96b5bd72012-10-15 08:30:45 +00001584 if (ret || found_key.objectid != ino ||
1585 (found_key.type != BTRFS_INODE_REF_KEY &&
1586 found_key.type != BTRFS_INODE_EXTREF_KEY)) {
Alexander Block31db9f72012-07-25 23:19:24 +02001587 ret = -ENOENT;
1588 goto out;
1589 }
1590
Jan Schmidt96b5bd72012-10-15 08:30:45 +00001591 if (key.type == BTRFS_INODE_REF_KEY) {
1592 struct btrfs_inode_ref *iref;
1593 iref = btrfs_item_ptr(path->nodes[0], path->slots[0],
1594 struct btrfs_inode_ref);
1595 len = btrfs_inode_ref_name_len(path->nodes[0], iref);
1596 ret = fs_path_add_from_extent_buffer(name, path->nodes[0],
1597 (unsigned long)(iref + 1),
1598 len);
1599 parent_dir = found_key.offset;
1600 } else {
1601 struct btrfs_inode_extref *extref;
1602 extref = btrfs_item_ptr(path->nodes[0], path->slots[0],
1603 struct btrfs_inode_extref);
1604 len = btrfs_inode_extref_name_len(path->nodes[0], extref);
1605 ret = fs_path_add_from_extent_buffer(name, path->nodes[0],
1606 (unsigned long)&extref->name, len);
1607 parent_dir = btrfs_inode_extref_parent(path->nodes[0], extref);
1608 }
Alexander Block31db9f72012-07-25 23:19:24 +02001609 if (ret < 0)
1610 goto out;
1611 btrfs_release_path(path);
1612
Jan Schmidt96b5bd72012-10-15 08:30:45 +00001613 ret = get_inode_info(root, parent_dir, NULL, dir_gen, NULL, NULL,
Alexander Block85a7b332012-07-26 23:39:10 +02001614 NULL, NULL);
Alexander Block31db9f72012-07-25 23:19:24 +02001615 if (ret < 0)
1616 goto out;
1617
Jan Schmidt96b5bd72012-10-15 08:30:45 +00001618 *dir = parent_dir;
Alexander Block31db9f72012-07-25 23:19:24 +02001619
1620out:
1621 btrfs_free_path(path);
1622 return ret;
1623}
1624
Tsutomu Itoh924794c2013-05-08 07:51:52 +00001625static int is_first_ref(struct btrfs_root *root,
Alexander Block31db9f72012-07-25 23:19:24 +02001626 u64 ino, u64 dir,
1627 const char *name, int name_len)
1628{
1629 int ret;
1630 struct fs_path *tmp_name;
1631 u64 tmp_dir;
1632 u64 tmp_dir_gen;
1633
Tsutomu Itoh924794c2013-05-08 07:51:52 +00001634 tmp_name = fs_path_alloc();
Alexander Block31db9f72012-07-25 23:19:24 +02001635 if (!tmp_name)
1636 return -ENOMEM;
1637
Tsutomu Itoh924794c2013-05-08 07:51:52 +00001638 ret = get_first_ref(root, ino, &tmp_dir, &tmp_dir_gen, tmp_name);
Alexander Block31db9f72012-07-25 23:19:24 +02001639 if (ret < 0)
1640 goto out;
1641
Alexander Blockb9291af2012-07-28 11:07:18 +02001642 if (dir != tmp_dir || name_len != fs_path_len(tmp_name)) {
Alexander Block31db9f72012-07-25 23:19:24 +02001643 ret = 0;
1644 goto out;
1645 }
1646
Alexander Blocke938c8a2012-07-28 16:33:49 +02001647 ret = !memcmp(tmp_name->start, name, name_len);
Alexander Block31db9f72012-07-25 23:19:24 +02001648
1649out:
Tsutomu Itoh924794c2013-05-08 07:51:52 +00001650 fs_path_free(tmp_name);
Alexander Block31db9f72012-07-25 23:19:24 +02001651 return ret;
1652}
1653
Alexander Block766702e2012-07-28 14:11:31 +02001654/*
1655 * Used by process_recorded_refs to determine if a new ref would overwrite an
1656 * already existing ref. In case it detects an overwrite, it returns the
1657 * inode/gen in who_ino/who_gen.
1658 * When an overwrite is detected, process_recorded_refs does proper orphanizing
1659 * to make sure later references to the overwritten inode are possible.
1660 * Orphanizing is however only required for the first ref of an inode.
1661 * process_recorded_refs does an additional is_first_ref check to see if
1662 * orphanizing is really required.
1663 */
Alexander Block31db9f72012-07-25 23:19:24 +02001664static int will_overwrite_ref(struct send_ctx *sctx, u64 dir, u64 dir_gen,
1665 const char *name, int name_len,
1666 u64 *who_ino, u64 *who_gen)
1667{
1668 int ret = 0;
Josef Bacikebdad912013-08-06 16:47:48 -04001669 u64 gen;
Alexander Block31db9f72012-07-25 23:19:24 +02001670 u64 other_inode = 0;
1671 u8 other_type = 0;
1672
1673 if (!sctx->parent_root)
1674 goto out;
1675
1676 ret = is_inode_existent(sctx, dir, dir_gen);
1677 if (ret <= 0)
1678 goto out;
1679
Josef Bacikebdad912013-08-06 16:47:48 -04001680 /*
1681 * If we have a parent root we need to verify that the parent dir was
1682 * not delted and then re-created, if it was then we have no overwrite
1683 * and we can just unlink this entry.
1684 */
1685 if (sctx->parent_root) {
1686 ret = get_inode_info(sctx->parent_root, dir, NULL, &gen, NULL,
1687 NULL, NULL, NULL);
1688 if (ret < 0 && ret != -ENOENT)
1689 goto out;
1690 if (ret) {
1691 ret = 0;
1692 goto out;
1693 }
1694 if (gen != dir_gen)
1695 goto out;
1696 }
1697
Alexander Block31db9f72012-07-25 23:19:24 +02001698 ret = lookup_dir_item_inode(sctx->parent_root, dir, name, name_len,
1699 &other_inode, &other_type);
1700 if (ret < 0 && ret != -ENOENT)
1701 goto out;
1702 if (ret) {
1703 ret = 0;
1704 goto out;
1705 }
1706
Alexander Block766702e2012-07-28 14:11:31 +02001707 /*
1708 * Check if the overwritten ref was already processed. If yes, the ref
1709 * was already unlinked/moved, so we can safely assume that we will not
1710 * overwrite anything at this point in time.
1711 */
Alexander Block31db9f72012-07-25 23:19:24 +02001712 if (other_inode > sctx->send_progress) {
1713 ret = get_inode_info(sctx->parent_root, other_inode, NULL,
Alexander Block85a7b332012-07-26 23:39:10 +02001714 who_gen, NULL, NULL, NULL, NULL);
Alexander Block31db9f72012-07-25 23:19:24 +02001715 if (ret < 0)
1716 goto out;
1717
1718 ret = 1;
1719 *who_ino = other_inode;
1720 } else {
1721 ret = 0;
1722 }
1723
1724out:
1725 return ret;
1726}
1727
Alexander Block766702e2012-07-28 14:11:31 +02001728/*
1729 * Checks if the ref was overwritten by an already processed inode. This is
1730 * used by __get_cur_name_and_parent to find out if the ref was orphanized and
1731 * thus the orphan name needs be used.
1732 * process_recorded_refs also uses it to avoid unlinking of refs that were
1733 * overwritten.
1734 */
Alexander Block31db9f72012-07-25 23:19:24 +02001735static int did_overwrite_ref(struct send_ctx *sctx,
1736 u64 dir, u64 dir_gen,
1737 u64 ino, u64 ino_gen,
1738 const char *name, int name_len)
1739{
1740 int ret = 0;
1741 u64 gen;
1742 u64 ow_inode;
1743 u8 other_type;
1744
1745 if (!sctx->parent_root)
1746 goto out;
1747
1748 ret = is_inode_existent(sctx, dir, dir_gen);
1749 if (ret <= 0)
1750 goto out;
1751
1752 /* check if the ref was overwritten by another ref */
1753 ret = lookup_dir_item_inode(sctx->send_root, dir, name, name_len,
1754 &ow_inode, &other_type);
1755 if (ret < 0 && ret != -ENOENT)
1756 goto out;
1757 if (ret) {
1758 /* was never and will never be overwritten */
1759 ret = 0;
1760 goto out;
1761 }
1762
1763 ret = get_inode_info(sctx->send_root, ow_inode, NULL, &gen, NULL, NULL,
Alexander Block85a7b332012-07-26 23:39:10 +02001764 NULL, NULL);
Alexander Block31db9f72012-07-25 23:19:24 +02001765 if (ret < 0)
1766 goto out;
1767
1768 if (ow_inode == ino && gen == ino_gen) {
1769 ret = 0;
1770 goto out;
1771 }
1772
1773 /* we know that it is or will be overwritten. check this now */
1774 if (ow_inode < sctx->send_progress)
1775 ret = 1;
1776 else
1777 ret = 0;
1778
1779out:
1780 return ret;
1781}
1782
Alexander Block766702e2012-07-28 14:11:31 +02001783/*
1784 * Same as did_overwrite_ref, but also checks if it is the first ref of an inode
1785 * that got overwritten. This is used by process_recorded_refs to determine
1786 * if it has to use the path as returned by get_cur_path or the orphan name.
1787 */
Alexander Block31db9f72012-07-25 23:19:24 +02001788static int did_overwrite_first_ref(struct send_ctx *sctx, u64 ino, u64 gen)
1789{
1790 int ret = 0;
1791 struct fs_path *name = NULL;
1792 u64 dir;
1793 u64 dir_gen;
1794
1795 if (!sctx->parent_root)
1796 goto out;
1797
Tsutomu Itoh924794c2013-05-08 07:51:52 +00001798 name = fs_path_alloc();
Alexander Block31db9f72012-07-25 23:19:24 +02001799 if (!name)
1800 return -ENOMEM;
1801
Tsutomu Itoh924794c2013-05-08 07:51:52 +00001802 ret = get_first_ref(sctx->parent_root, ino, &dir, &dir_gen, name);
Alexander Block31db9f72012-07-25 23:19:24 +02001803 if (ret < 0)
1804 goto out;
1805
1806 ret = did_overwrite_ref(sctx, dir, dir_gen, ino, gen,
1807 name->start, fs_path_len(name));
Alexander Block31db9f72012-07-25 23:19:24 +02001808
1809out:
Tsutomu Itoh924794c2013-05-08 07:51:52 +00001810 fs_path_free(name);
Alexander Block31db9f72012-07-25 23:19:24 +02001811 return ret;
1812}
1813
Alexander Block766702e2012-07-28 14:11:31 +02001814/*
1815 * Insert a name cache entry. On 32bit kernels the radix tree index is 32bit,
1816 * so we need to do some special handling in case we have clashes. This function
1817 * takes care of this with the help of name_cache_entry::radix_list.
Alexander Block5dc67d02012-08-01 12:07:43 +02001818 * In case of error, nce is kfreed.
Alexander Block766702e2012-07-28 14:11:31 +02001819 */
Alexander Block31db9f72012-07-25 23:19:24 +02001820static int name_cache_insert(struct send_ctx *sctx,
1821 struct name_cache_entry *nce)
1822{
1823 int ret = 0;
Alexander Block7e0926f2012-07-28 14:20:58 +02001824 struct list_head *nce_head;
Alexander Block31db9f72012-07-25 23:19:24 +02001825
Alexander Block7e0926f2012-07-28 14:20:58 +02001826 nce_head = radix_tree_lookup(&sctx->name_cache,
1827 (unsigned long)nce->ino);
1828 if (!nce_head) {
1829 nce_head = kmalloc(sizeof(*nce_head), GFP_NOFS);
Tsutomu Itohcfa7a9c2012-12-17 06:38:51 +00001830 if (!nce_head) {
1831 kfree(nce);
Alexander Block31db9f72012-07-25 23:19:24 +02001832 return -ENOMEM;
Tsutomu Itohcfa7a9c2012-12-17 06:38:51 +00001833 }
Alexander Block7e0926f2012-07-28 14:20:58 +02001834 INIT_LIST_HEAD(nce_head);
Alexander Block31db9f72012-07-25 23:19:24 +02001835
Alexander Block7e0926f2012-07-28 14:20:58 +02001836 ret = radix_tree_insert(&sctx->name_cache, nce->ino, nce_head);
Alexander Block5dc67d02012-08-01 12:07:43 +02001837 if (ret < 0) {
1838 kfree(nce_head);
1839 kfree(nce);
Alexander Block31db9f72012-07-25 23:19:24 +02001840 return ret;
Alexander Block5dc67d02012-08-01 12:07:43 +02001841 }
Alexander Block31db9f72012-07-25 23:19:24 +02001842 }
Alexander Block7e0926f2012-07-28 14:20:58 +02001843 list_add_tail(&nce->radix_list, nce_head);
Alexander Block31db9f72012-07-25 23:19:24 +02001844 list_add_tail(&nce->list, &sctx->name_cache_list);
1845 sctx->name_cache_size++;
1846
1847 return ret;
1848}
1849
1850static void name_cache_delete(struct send_ctx *sctx,
1851 struct name_cache_entry *nce)
1852{
Alexander Block7e0926f2012-07-28 14:20:58 +02001853 struct list_head *nce_head;
Alexander Block31db9f72012-07-25 23:19:24 +02001854
Alexander Block7e0926f2012-07-28 14:20:58 +02001855 nce_head = radix_tree_lookup(&sctx->name_cache,
1856 (unsigned long)nce->ino);
1857 BUG_ON(!nce_head);
Alexander Block31db9f72012-07-25 23:19:24 +02001858
Alexander Block7e0926f2012-07-28 14:20:58 +02001859 list_del(&nce->radix_list);
Alexander Block31db9f72012-07-25 23:19:24 +02001860 list_del(&nce->list);
Alexander Block31db9f72012-07-25 23:19:24 +02001861 sctx->name_cache_size--;
Alexander Block7e0926f2012-07-28 14:20:58 +02001862
1863 if (list_empty(nce_head)) {
1864 radix_tree_delete(&sctx->name_cache, (unsigned long)nce->ino);
1865 kfree(nce_head);
1866 }
Alexander Block31db9f72012-07-25 23:19:24 +02001867}
1868
1869static struct name_cache_entry *name_cache_search(struct send_ctx *sctx,
1870 u64 ino, u64 gen)
1871{
Alexander Block7e0926f2012-07-28 14:20:58 +02001872 struct list_head *nce_head;
1873 struct name_cache_entry *cur;
Alexander Block31db9f72012-07-25 23:19:24 +02001874
Alexander Block7e0926f2012-07-28 14:20:58 +02001875 nce_head = radix_tree_lookup(&sctx->name_cache, (unsigned long)ino);
1876 if (!nce_head)
Alexander Block31db9f72012-07-25 23:19:24 +02001877 return NULL;
1878
Alexander Block7e0926f2012-07-28 14:20:58 +02001879 list_for_each_entry(cur, nce_head, radix_list) {
1880 if (cur->ino == ino && cur->gen == gen)
1881 return cur;
1882 }
Alexander Block31db9f72012-07-25 23:19:24 +02001883 return NULL;
1884}
1885
Alexander Block766702e2012-07-28 14:11:31 +02001886/*
1887 * Removes the entry from the list and adds it back to the end. This marks the
1888 * entry as recently used so that name_cache_clean_unused does not remove it.
1889 */
Alexander Block31db9f72012-07-25 23:19:24 +02001890static void name_cache_used(struct send_ctx *sctx, struct name_cache_entry *nce)
1891{
1892 list_del(&nce->list);
1893 list_add_tail(&nce->list, &sctx->name_cache_list);
1894}
1895
Alexander Block766702e2012-07-28 14:11:31 +02001896/*
1897 * Remove some entries from the beginning of name_cache_list.
1898 */
Alexander Block31db9f72012-07-25 23:19:24 +02001899static void name_cache_clean_unused(struct send_ctx *sctx)
1900{
1901 struct name_cache_entry *nce;
1902
1903 if (sctx->name_cache_size < SEND_CTX_NAME_CACHE_CLEAN_SIZE)
1904 return;
1905
1906 while (sctx->name_cache_size > SEND_CTX_MAX_NAME_CACHE_SIZE) {
1907 nce = list_entry(sctx->name_cache_list.next,
1908 struct name_cache_entry, list);
1909 name_cache_delete(sctx, nce);
1910 kfree(nce);
1911 }
1912}
1913
1914static void name_cache_free(struct send_ctx *sctx)
1915{
1916 struct name_cache_entry *nce;
Alexander Block31db9f72012-07-25 23:19:24 +02001917
Alexander Blocke938c8a2012-07-28 16:33:49 +02001918 while (!list_empty(&sctx->name_cache_list)) {
1919 nce = list_entry(sctx->name_cache_list.next,
1920 struct name_cache_entry, list);
Alexander Block31db9f72012-07-25 23:19:24 +02001921 name_cache_delete(sctx, nce);
Alexander Block17589bd2012-07-28 14:13:35 +02001922 kfree(nce);
Alexander Block31db9f72012-07-25 23:19:24 +02001923 }
1924}
1925
Alexander Block766702e2012-07-28 14:11:31 +02001926/*
1927 * Used by get_cur_path for each ref up to the root.
1928 * Returns 0 if it succeeded.
1929 * Returns 1 if the inode is not existent or got overwritten. In that case, the
1930 * name is an orphan name. This instructs get_cur_path to stop iterating. If 1
1931 * is returned, parent_ino/parent_gen are not guaranteed to be valid.
1932 * Returns <0 in case of error.
1933 */
Alexander Block31db9f72012-07-25 23:19:24 +02001934static int __get_cur_name_and_parent(struct send_ctx *sctx,
1935 u64 ino, u64 gen,
1936 u64 *parent_ino,
1937 u64 *parent_gen,
1938 struct fs_path *dest)
1939{
1940 int ret;
1941 int nce_ret;
1942 struct btrfs_path *path = NULL;
1943 struct name_cache_entry *nce = NULL;
1944
Alexander Block766702e2012-07-28 14:11:31 +02001945 /*
1946 * First check if we already did a call to this function with the same
1947 * ino/gen. If yes, check if the cache entry is still up-to-date. If yes
1948 * return the cached result.
1949 */
Alexander Block31db9f72012-07-25 23:19:24 +02001950 nce = name_cache_search(sctx, ino, gen);
1951 if (nce) {
1952 if (ino < sctx->send_progress && nce->need_later_update) {
1953 name_cache_delete(sctx, nce);
1954 kfree(nce);
1955 nce = NULL;
1956 } else {
1957 name_cache_used(sctx, nce);
1958 *parent_ino = nce->parent_ino;
1959 *parent_gen = nce->parent_gen;
1960 ret = fs_path_add(dest, nce->name, nce->name_len);
1961 if (ret < 0)
1962 goto out;
1963 ret = nce->ret;
1964 goto out;
1965 }
1966 }
1967
1968 path = alloc_path_for_send();
1969 if (!path)
1970 return -ENOMEM;
1971
Alexander Block766702e2012-07-28 14:11:31 +02001972 /*
1973 * If the inode is not existent yet, add the orphan name and return 1.
1974 * This should only happen for the parent dir that we determine in
1975 * __record_new_ref
1976 */
Alexander Block31db9f72012-07-25 23:19:24 +02001977 ret = is_inode_existent(sctx, ino, gen);
1978 if (ret < 0)
1979 goto out;
1980
1981 if (!ret) {
1982 ret = gen_unique_name(sctx, ino, gen, dest);
1983 if (ret < 0)
1984 goto out;
1985 ret = 1;
1986 goto out_cache;
1987 }
1988
Alexander Block766702e2012-07-28 14:11:31 +02001989 /*
1990 * Depending on whether the inode was already processed or not, use
1991 * send_root or parent_root for ref lookup.
1992 */
Alexander Block31db9f72012-07-25 23:19:24 +02001993 if (ino < sctx->send_progress)
Tsutomu Itoh924794c2013-05-08 07:51:52 +00001994 ret = get_first_ref(sctx->send_root, ino,
1995 parent_ino, parent_gen, dest);
Alexander Block31db9f72012-07-25 23:19:24 +02001996 else
Tsutomu Itoh924794c2013-05-08 07:51:52 +00001997 ret = get_first_ref(sctx->parent_root, ino,
1998 parent_ino, parent_gen, dest);
Alexander Block31db9f72012-07-25 23:19:24 +02001999 if (ret < 0)
2000 goto out;
2001
Alexander Block766702e2012-07-28 14:11:31 +02002002 /*
2003 * Check if the ref was overwritten by an inode's ref that was processed
2004 * earlier. If yes, treat as orphan and return 1.
2005 */
Alexander Block31db9f72012-07-25 23:19:24 +02002006 ret = did_overwrite_ref(sctx, *parent_ino, *parent_gen, ino, gen,
2007 dest->start, dest->end - dest->start);
2008 if (ret < 0)
2009 goto out;
2010 if (ret) {
2011 fs_path_reset(dest);
2012 ret = gen_unique_name(sctx, ino, gen, dest);
2013 if (ret < 0)
2014 goto out;
2015 ret = 1;
2016 }
2017
2018out_cache:
Alexander Block766702e2012-07-28 14:11:31 +02002019 /*
2020 * Store the result of the lookup in the name cache.
2021 */
Alexander Block31db9f72012-07-25 23:19:24 +02002022 nce = kmalloc(sizeof(*nce) + fs_path_len(dest) + 1, GFP_NOFS);
2023 if (!nce) {
2024 ret = -ENOMEM;
2025 goto out;
2026 }
2027
2028 nce->ino = ino;
2029 nce->gen = gen;
2030 nce->parent_ino = *parent_ino;
2031 nce->parent_gen = *parent_gen;
2032 nce->name_len = fs_path_len(dest);
2033 nce->ret = ret;
2034 strcpy(nce->name, dest->start);
Alexander Block31db9f72012-07-25 23:19:24 +02002035
2036 if (ino < sctx->send_progress)
2037 nce->need_later_update = 0;
2038 else
2039 nce->need_later_update = 1;
2040
2041 nce_ret = name_cache_insert(sctx, nce);
2042 if (nce_ret < 0)
2043 ret = nce_ret;
2044 name_cache_clean_unused(sctx);
2045
2046out:
2047 btrfs_free_path(path);
2048 return ret;
2049}
2050
2051/*
2052 * Magic happens here. This function returns the first ref to an inode as it
2053 * would look like while receiving the stream at this point in time.
2054 * We walk the path up to the root. For every inode in between, we check if it
2055 * was already processed/sent. If yes, we continue with the parent as found
2056 * in send_root. If not, we continue with the parent as found in parent_root.
2057 * If we encounter an inode that was deleted at this point in time, we use the
2058 * inodes "orphan" name instead of the real name and stop. Same with new inodes
2059 * that were not created yet and overwritten inodes/refs.
2060 *
2061 * When do we have have orphan inodes:
2062 * 1. When an inode is freshly created and thus no valid refs are available yet
2063 * 2. When a directory lost all it's refs (deleted) but still has dir items
2064 * inside which were not processed yet (pending for move/delete). If anyone
2065 * tried to get the path to the dir items, it would get a path inside that
2066 * orphan directory.
2067 * 3. When an inode is moved around or gets new links, it may overwrite the ref
2068 * of an unprocessed inode. If in that case the first ref would be
2069 * overwritten, the overwritten inode gets "orphanized". Later when we
2070 * process this overwritten inode, it is restored at a new place by moving
2071 * the orphan inode.
2072 *
2073 * sctx->send_progress tells this function at which point in time receiving
2074 * would be.
2075 */
2076static int get_cur_path(struct send_ctx *sctx, u64 ino, u64 gen,
2077 struct fs_path *dest)
2078{
2079 int ret = 0;
2080 struct fs_path *name = NULL;
2081 u64 parent_inode = 0;
2082 u64 parent_gen = 0;
2083 int stop = 0;
2084
Tsutomu Itoh924794c2013-05-08 07:51:52 +00002085 name = fs_path_alloc();
Alexander Block31db9f72012-07-25 23:19:24 +02002086 if (!name) {
2087 ret = -ENOMEM;
2088 goto out;
2089 }
2090
2091 dest->reversed = 1;
2092 fs_path_reset(dest);
2093
2094 while (!stop && ino != BTRFS_FIRST_FREE_OBJECTID) {
2095 fs_path_reset(name);
2096
2097 ret = __get_cur_name_and_parent(sctx, ino, gen,
2098 &parent_inode, &parent_gen, name);
2099 if (ret < 0)
2100 goto out;
2101 if (ret)
2102 stop = 1;
2103
2104 ret = fs_path_add_path(dest, name);
2105 if (ret < 0)
2106 goto out;
2107
2108 ino = parent_inode;
2109 gen = parent_gen;
2110 }
2111
2112out:
Tsutomu Itoh924794c2013-05-08 07:51:52 +00002113 fs_path_free(name);
Alexander Block31db9f72012-07-25 23:19:24 +02002114 if (!ret)
2115 fs_path_unreverse(dest);
2116 return ret;
2117}
2118
2119/*
Alexander Block31db9f72012-07-25 23:19:24 +02002120 * Sends a BTRFS_SEND_C_SUBVOL command/item to userspace
2121 */
2122static int send_subvol_begin(struct send_ctx *sctx)
2123{
2124 int ret;
2125 struct btrfs_root *send_root = sctx->send_root;
2126 struct btrfs_root *parent_root = sctx->parent_root;
2127 struct btrfs_path *path;
2128 struct btrfs_key key;
2129 struct btrfs_root_ref *ref;
2130 struct extent_buffer *leaf;
2131 char *name = NULL;
2132 int namelen;
2133
2134 path = alloc_path_for_send();
2135 if (!path)
2136 return -ENOMEM;
2137
2138 name = kmalloc(BTRFS_PATH_NAME_MAX, GFP_NOFS);
2139 if (!name) {
2140 btrfs_free_path(path);
2141 return -ENOMEM;
2142 }
2143
2144 key.objectid = send_root->objectid;
2145 key.type = BTRFS_ROOT_BACKREF_KEY;
2146 key.offset = 0;
2147
2148 ret = btrfs_search_slot_for_read(send_root->fs_info->tree_root,
2149 &key, path, 1, 0);
2150 if (ret < 0)
2151 goto out;
2152 if (ret) {
2153 ret = -ENOENT;
2154 goto out;
2155 }
2156
2157 leaf = path->nodes[0];
2158 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2159 if (key.type != BTRFS_ROOT_BACKREF_KEY ||
2160 key.objectid != send_root->objectid) {
2161 ret = -ENOENT;
2162 goto out;
2163 }
2164 ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_ref);
2165 namelen = btrfs_root_ref_name_len(leaf, ref);
2166 read_extent_buffer(leaf, name, (unsigned long)(ref + 1), namelen);
2167 btrfs_release_path(path);
2168
Alexander Block31db9f72012-07-25 23:19:24 +02002169 if (parent_root) {
2170 ret = begin_cmd(sctx, BTRFS_SEND_C_SNAPSHOT);
2171 if (ret < 0)
2172 goto out;
2173 } else {
2174 ret = begin_cmd(sctx, BTRFS_SEND_C_SUBVOL);
2175 if (ret < 0)
2176 goto out;
2177 }
2178
2179 TLV_PUT_STRING(sctx, BTRFS_SEND_A_PATH, name, namelen);
2180 TLV_PUT_UUID(sctx, BTRFS_SEND_A_UUID,
2181 sctx->send_root->root_item.uuid);
2182 TLV_PUT_U64(sctx, BTRFS_SEND_A_CTRANSID,
2183 sctx->send_root->root_item.ctransid);
2184 if (parent_root) {
2185 TLV_PUT_UUID(sctx, BTRFS_SEND_A_CLONE_UUID,
2186 sctx->parent_root->root_item.uuid);
2187 TLV_PUT_U64(sctx, BTRFS_SEND_A_CLONE_CTRANSID,
2188 sctx->parent_root->root_item.ctransid);
2189 }
2190
2191 ret = send_cmd(sctx);
2192
2193tlv_put_failure:
2194out:
2195 btrfs_free_path(path);
2196 kfree(name);
2197 return ret;
2198}
2199
2200static int send_truncate(struct send_ctx *sctx, u64 ino, u64 gen, u64 size)
2201{
2202 int ret = 0;
2203 struct fs_path *p;
2204
2205verbose_printk("btrfs: send_truncate %llu size=%llu\n", ino, size);
2206
Tsutomu Itoh924794c2013-05-08 07:51:52 +00002207 p = fs_path_alloc();
Alexander Block31db9f72012-07-25 23:19:24 +02002208 if (!p)
2209 return -ENOMEM;
2210
2211 ret = begin_cmd(sctx, BTRFS_SEND_C_TRUNCATE);
2212 if (ret < 0)
2213 goto out;
2214
2215 ret = get_cur_path(sctx, ino, gen, p);
2216 if (ret < 0)
2217 goto out;
2218 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, p);
2219 TLV_PUT_U64(sctx, BTRFS_SEND_A_SIZE, size);
2220
2221 ret = send_cmd(sctx);
2222
2223tlv_put_failure:
2224out:
Tsutomu Itoh924794c2013-05-08 07:51:52 +00002225 fs_path_free(p);
Alexander Block31db9f72012-07-25 23:19:24 +02002226 return ret;
2227}
2228
2229static int send_chmod(struct send_ctx *sctx, u64 ino, u64 gen, u64 mode)
2230{
2231 int ret = 0;
2232 struct fs_path *p;
2233
2234verbose_printk("btrfs: send_chmod %llu mode=%llu\n", ino, mode);
2235
Tsutomu Itoh924794c2013-05-08 07:51:52 +00002236 p = fs_path_alloc();
Alexander Block31db9f72012-07-25 23:19:24 +02002237 if (!p)
2238 return -ENOMEM;
2239
2240 ret = begin_cmd(sctx, BTRFS_SEND_C_CHMOD);
2241 if (ret < 0)
2242 goto out;
2243
2244 ret = get_cur_path(sctx, ino, gen, p);
2245 if (ret < 0)
2246 goto out;
2247 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, p);
2248 TLV_PUT_U64(sctx, BTRFS_SEND_A_MODE, mode & 07777);
2249
2250 ret = send_cmd(sctx);
2251
2252tlv_put_failure:
2253out:
Tsutomu Itoh924794c2013-05-08 07:51:52 +00002254 fs_path_free(p);
Alexander Block31db9f72012-07-25 23:19:24 +02002255 return ret;
2256}
2257
2258static int send_chown(struct send_ctx *sctx, u64 ino, u64 gen, u64 uid, u64 gid)
2259{
2260 int ret = 0;
2261 struct fs_path *p;
2262
2263verbose_printk("btrfs: send_chown %llu uid=%llu, gid=%llu\n", ino, uid, gid);
2264
Tsutomu Itoh924794c2013-05-08 07:51:52 +00002265 p = fs_path_alloc();
Alexander Block31db9f72012-07-25 23:19:24 +02002266 if (!p)
2267 return -ENOMEM;
2268
2269 ret = begin_cmd(sctx, BTRFS_SEND_C_CHOWN);
2270 if (ret < 0)
2271 goto out;
2272
2273 ret = get_cur_path(sctx, ino, gen, p);
2274 if (ret < 0)
2275 goto out;
2276 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, p);
2277 TLV_PUT_U64(sctx, BTRFS_SEND_A_UID, uid);
2278 TLV_PUT_U64(sctx, BTRFS_SEND_A_GID, gid);
2279
2280 ret = send_cmd(sctx);
2281
2282tlv_put_failure:
2283out:
Tsutomu Itoh924794c2013-05-08 07:51:52 +00002284 fs_path_free(p);
Alexander Block31db9f72012-07-25 23:19:24 +02002285 return ret;
2286}
2287
2288static int send_utimes(struct send_ctx *sctx, u64 ino, u64 gen)
2289{
2290 int ret = 0;
2291 struct fs_path *p = NULL;
2292 struct btrfs_inode_item *ii;
2293 struct btrfs_path *path = NULL;
2294 struct extent_buffer *eb;
2295 struct btrfs_key key;
2296 int slot;
2297
2298verbose_printk("btrfs: send_utimes %llu\n", ino);
2299
Tsutomu Itoh924794c2013-05-08 07:51:52 +00002300 p = fs_path_alloc();
Alexander Block31db9f72012-07-25 23:19:24 +02002301 if (!p)
2302 return -ENOMEM;
2303
2304 path = alloc_path_for_send();
2305 if (!path) {
2306 ret = -ENOMEM;
2307 goto out;
2308 }
2309
2310 key.objectid = ino;
2311 key.type = BTRFS_INODE_ITEM_KEY;
2312 key.offset = 0;
2313 ret = btrfs_search_slot(NULL, sctx->send_root, &key, path, 0, 0);
2314 if (ret < 0)
2315 goto out;
2316
2317 eb = path->nodes[0];
2318 slot = path->slots[0];
2319 ii = btrfs_item_ptr(eb, slot, struct btrfs_inode_item);
2320
2321 ret = begin_cmd(sctx, BTRFS_SEND_C_UTIMES);
2322 if (ret < 0)
2323 goto out;
2324
2325 ret = get_cur_path(sctx, ino, gen, p);
2326 if (ret < 0)
2327 goto out;
2328 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, p);
2329 TLV_PUT_BTRFS_TIMESPEC(sctx, BTRFS_SEND_A_ATIME, eb,
2330 btrfs_inode_atime(ii));
2331 TLV_PUT_BTRFS_TIMESPEC(sctx, BTRFS_SEND_A_MTIME, eb,
2332 btrfs_inode_mtime(ii));
2333 TLV_PUT_BTRFS_TIMESPEC(sctx, BTRFS_SEND_A_CTIME, eb,
2334 btrfs_inode_ctime(ii));
Alexander Block766702e2012-07-28 14:11:31 +02002335 /* TODO Add otime support when the otime patches get into upstream */
Alexander Block31db9f72012-07-25 23:19:24 +02002336
2337 ret = send_cmd(sctx);
2338
2339tlv_put_failure:
2340out:
Tsutomu Itoh924794c2013-05-08 07:51:52 +00002341 fs_path_free(p);
Alexander Block31db9f72012-07-25 23:19:24 +02002342 btrfs_free_path(path);
2343 return ret;
2344}
2345
2346/*
2347 * Sends a BTRFS_SEND_C_MKXXX or SYMLINK command to user space. We don't have
2348 * a valid path yet because we did not process the refs yet. So, the inode
2349 * is created as orphan.
2350 */
Alexander Block1f4692d2012-07-28 10:42:24 +02002351static int send_create_inode(struct send_ctx *sctx, u64 ino)
Alexander Block31db9f72012-07-25 23:19:24 +02002352{
2353 int ret = 0;
Alexander Block31db9f72012-07-25 23:19:24 +02002354 struct fs_path *p;
Alexander Block31db9f72012-07-25 23:19:24 +02002355 int cmd;
Alexander Block1f4692d2012-07-28 10:42:24 +02002356 u64 gen;
Alexander Block31db9f72012-07-25 23:19:24 +02002357 u64 mode;
Alexander Block1f4692d2012-07-28 10:42:24 +02002358 u64 rdev;
Alexander Block31db9f72012-07-25 23:19:24 +02002359
Alexander Block1f4692d2012-07-28 10:42:24 +02002360verbose_printk("btrfs: send_create_inode %llu\n", ino);
Alexander Block31db9f72012-07-25 23:19:24 +02002361
Tsutomu Itoh924794c2013-05-08 07:51:52 +00002362 p = fs_path_alloc();
Alexander Block31db9f72012-07-25 23:19:24 +02002363 if (!p)
2364 return -ENOMEM;
2365
Alexander Block1f4692d2012-07-28 10:42:24 +02002366 ret = get_inode_info(sctx->send_root, ino, NULL, &gen, &mode, NULL,
2367 NULL, &rdev);
2368 if (ret < 0)
2369 goto out;
Alexander Block31db9f72012-07-25 23:19:24 +02002370
Alexander Blocke938c8a2012-07-28 16:33:49 +02002371 if (S_ISREG(mode)) {
Alexander Block31db9f72012-07-25 23:19:24 +02002372 cmd = BTRFS_SEND_C_MKFILE;
Alexander Blocke938c8a2012-07-28 16:33:49 +02002373 } else if (S_ISDIR(mode)) {
Alexander Block31db9f72012-07-25 23:19:24 +02002374 cmd = BTRFS_SEND_C_MKDIR;
Alexander Blocke938c8a2012-07-28 16:33:49 +02002375 } else if (S_ISLNK(mode)) {
Alexander Block31db9f72012-07-25 23:19:24 +02002376 cmd = BTRFS_SEND_C_SYMLINK;
Alexander Blocke938c8a2012-07-28 16:33:49 +02002377 } else if (S_ISCHR(mode) || S_ISBLK(mode)) {
Alexander Block31db9f72012-07-25 23:19:24 +02002378 cmd = BTRFS_SEND_C_MKNOD;
Alexander Blocke938c8a2012-07-28 16:33:49 +02002379 } else if (S_ISFIFO(mode)) {
Alexander Block31db9f72012-07-25 23:19:24 +02002380 cmd = BTRFS_SEND_C_MKFIFO;
Alexander Blocke938c8a2012-07-28 16:33:49 +02002381 } else if (S_ISSOCK(mode)) {
Alexander Block31db9f72012-07-25 23:19:24 +02002382 cmd = BTRFS_SEND_C_MKSOCK;
Alexander Blocke938c8a2012-07-28 16:33:49 +02002383 } else {
Alexander Block31db9f72012-07-25 23:19:24 +02002384 printk(KERN_WARNING "btrfs: unexpected inode type %o",
2385 (int)(mode & S_IFMT));
2386 ret = -ENOTSUPP;
2387 goto out;
2388 }
2389
2390 ret = begin_cmd(sctx, cmd);
2391 if (ret < 0)
2392 goto out;
2393
Alexander Block1f4692d2012-07-28 10:42:24 +02002394 ret = gen_unique_name(sctx, ino, gen, p);
Alexander Block31db9f72012-07-25 23:19:24 +02002395 if (ret < 0)
2396 goto out;
2397
2398 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, p);
Alexander Block1f4692d2012-07-28 10:42:24 +02002399 TLV_PUT_U64(sctx, BTRFS_SEND_A_INO, ino);
Alexander Block31db9f72012-07-25 23:19:24 +02002400
2401 if (S_ISLNK(mode)) {
2402 fs_path_reset(p);
Tsutomu Itoh924794c2013-05-08 07:51:52 +00002403 ret = read_symlink(sctx->send_root, ino, p);
Alexander Block31db9f72012-07-25 23:19:24 +02002404 if (ret < 0)
2405 goto out;
2406 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH_LINK, p);
2407 } else if (S_ISCHR(mode) || S_ISBLK(mode) ||
2408 S_ISFIFO(mode) || S_ISSOCK(mode)) {
Arne Jansend79e5042012-10-15 18:28:46 +00002409 TLV_PUT_U64(sctx, BTRFS_SEND_A_RDEV, new_encode_dev(rdev));
2410 TLV_PUT_U64(sctx, BTRFS_SEND_A_MODE, mode);
Alexander Block31db9f72012-07-25 23:19:24 +02002411 }
2412
2413 ret = send_cmd(sctx);
2414 if (ret < 0)
2415 goto out;
2416
2417
2418tlv_put_failure:
2419out:
Tsutomu Itoh924794c2013-05-08 07:51:52 +00002420 fs_path_free(p);
Alexander Block31db9f72012-07-25 23:19:24 +02002421 return ret;
2422}
2423
Alexander Block1f4692d2012-07-28 10:42:24 +02002424/*
2425 * We need some special handling for inodes that get processed before the parent
2426 * directory got created. See process_recorded_refs for details.
2427 * This function does the check if we already created the dir out of order.
2428 */
2429static int did_create_dir(struct send_ctx *sctx, u64 dir)
2430{
2431 int ret = 0;
2432 struct btrfs_path *path = NULL;
2433 struct btrfs_key key;
2434 struct btrfs_key found_key;
2435 struct btrfs_key di_key;
2436 struct extent_buffer *eb;
2437 struct btrfs_dir_item *di;
2438 int slot;
2439
2440 path = alloc_path_for_send();
2441 if (!path) {
2442 ret = -ENOMEM;
2443 goto out;
2444 }
2445
2446 key.objectid = dir;
2447 key.type = BTRFS_DIR_INDEX_KEY;
2448 key.offset = 0;
2449 while (1) {
2450 ret = btrfs_search_slot_for_read(sctx->send_root, &key, path,
2451 1, 0);
2452 if (ret < 0)
2453 goto out;
2454 if (!ret) {
2455 eb = path->nodes[0];
2456 slot = path->slots[0];
2457 btrfs_item_key_to_cpu(eb, &found_key, slot);
2458 }
2459 if (ret || found_key.objectid != key.objectid ||
2460 found_key.type != key.type) {
2461 ret = 0;
2462 goto out;
2463 }
2464
2465 di = btrfs_item_ptr(eb, slot, struct btrfs_dir_item);
2466 btrfs_dir_item_key_to_cpu(eb, di, &di_key);
2467
Josef Bacika0525412013-08-12 10:56:14 -04002468 if (di_key.type != BTRFS_ROOT_ITEM_KEY &&
2469 di_key.objectid < sctx->send_progress) {
Alexander Block1f4692d2012-07-28 10:42:24 +02002470 ret = 1;
2471 goto out;
2472 }
2473
2474 key.offset = found_key.offset + 1;
2475 btrfs_release_path(path);
2476 }
2477
2478out:
2479 btrfs_free_path(path);
2480 return ret;
2481}
2482
2483/*
2484 * Only creates the inode if it is:
2485 * 1. Not a directory
2486 * 2. Or a directory which was not created already due to out of order
2487 * directories. See did_create_dir and process_recorded_refs for details.
2488 */
2489static int send_create_inode_if_needed(struct send_ctx *sctx)
2490{
2491 int ret;
2492
2493 if (S_ISDIR(sctx->cur_inode_mode)) {
2494 ret = did_create_dir(sctx, sctx->cur_ino);
2495 if (ret < 0)
2496 goto out;
2497 if (ret) {
2498 ret = 0;
2499 goto out;
2500 }
2501 }
2502
2503 ret = send_create_inode(sctx, sctx->cur_ino);
2504 if (ret < 0)
2505 goto out;
2506
2507out:
2508 return ret;
2509}
2510
Alexander Block31db9f72012-07-25 23:19:24 +02002511struct recorded_ref {
2512 struct list_head list;
2513 char *dir_path;
2514 char *name;
2515 struct fs_path *full_path;
2516 u64 dir;
2517 u64 dir_gen;
2518 int dir_path_len;
2519 int name_len;
2520};
2521
2522/*
2523 * We need to process new refs before deleted refs, but compare_tree gives us
2524 * everything mixed. So we first record all refs and later process them.
2525 * This function is a helper to record one ref.
2526 */
2527static int record_ref(struct list_head *head, u64 dir,
2528 u64 dir_gen, struct fs_path *path)
2529{
2530 struct recorded_ref *ref;
Alexander Block31db9f72012-07-25 23:19:24 +02002531
2532 ref = kmalloc(sizeof(*ref), GFP_NOFS);
2533 if (!ref)
2534 return -ENOMEM;
2535
2536 ref->dir = dir;
2537 ref->dir_gen = dir_gen;
2538 ref->full_path = path;
2539
Andy Shevchenkoed848852013-08-21 10:32:13 +03002540 ref->name = (char *)kbasename(ref->full_path->start);
2541 ref->name_len = ref->full_path->end - ref->name;
2542 ref->dir_path = ref->full_path->start;
2543 if (ref->name == ref->full_path->start)
Alexander Block31db9f72012-07-25 23:19:24 +02002544 ref->dir_path_len = 0;
Andy Shevchenkoed848852013-08-21 10:32:13 +03002545 else
Alexander Block31db9f72012-07-25 23:19:24 +02002546 ref->dir_path_len = ref->full_path->end -
2547 ref->full_path->start - 1 - ref->name_len;
Alexander Block31db9f72012-07-25 23:19:24 +02002548
2549 list_add_tail(&ref->list, head);
2550 return 0;
2551}
2552
Josef Bacikba5e8f22013-08-16 16:52:55 -04002553static int dup_ref(struct recorded_ref *ref, struct list_head *list)
2554{
2555 struct recorded_ref *new;
2556
2557 new = kmalloc(sizeof(*ref), GFP_NOFS);
2558 if (!new)
2559 return -ENOMEM;
2560
2561 new->dir = ref->dir;
2562 new->dir_gen = ref->dir_gen;
2563 new->full_path = NULL;
2564 INIT_LIST_HEAD(&new->list);
2565 list_add_tail(&new->list, list);
2566 return 0;
2567}
2568
Tsutomu Itoh924794c2013-05-08 07:51:52 +00002569static void __free_recorded_refs(struct list_head *head)
Alexander Block31db9f72012-07-25 23:19:24 +02002570{
2571 struct recorded_ref *cur;
Alexander Block31db9f72012-07-25 23:19:24 +02002572
Alexander Blocke938c8a2012-07-28 16:33:49 +02002573 while (!list_empty(head)) {
2574 cur = list_entry(head->next, struct recorded_ref, list);
Tsutomu Itoh924794c2013-05-08 07:51:52 +00002575 fs_path_free(cur->full_path);
Alexander Blocke938c8a2012-07-28 16:33:49 +02002576 list_del(&cur->list);
Alexander Block31db9f72012-07-25 23:19:24 +02002577 kfree(cur);
2578 }
Alexander Block31db9f72012-07-25 23:19:24 +02002579}
2580
2581static void free_recorded_refs(struct send_ctx *sctx)
2582{
Tsutomu Itoh924794c2013-05-08 07:51:52 +00002583 __free_recorded_refs(&sctx->new_refs);
2584 __free_recorded_refs(&sctx->deleted_refs);
Alexander Block31db9f72012-07-25 23:19:24 +02002585}
2586
2587/*
Alexander Block766702e2012-07-28 14:11:31 +02002588 * Renames/moves a file/dir to its orphan name. Used when the first
Alexander Block31db9f72012-07-25 23:19:24 +02002589 * ref of an unprocessed inode gets overwritten and for all non empty
2590 * directories.
2591 */
2592static int orphanize_inode(struct send_ctx *sctx, u64 ino, u64 gen,
2593 struct fs_path *path)
2594{
2595 int ret;
2596 struct fs_path *orphan;
2597
Tsutomu Itoh924794c2013-05-08 07:51:52 +00002598 orphan = fs_path_alloc();
Alexander Block31db9f72012-07-25 23:19:24 +02002599 if (!orphan)
2600 return -ENOMEM;
2601
2602 ret = gen_unique_name(sctx, ino, gen, orphan);
2603 if (ret < 0)
2604 goto out;
2605
2606 ret = send_rename(sctx, path, orphan);
2607
2608out:
Tsutomu Itoh924794c2013-05-08 07:51:52 +00002609 fs_path_free(orphan);
Alexander Block31db9f72012-07-25 23:19:24 +02002610 return ret;
2611}
2612
2613/*
2614 * Returns 1 if a directory can be removed at this point in time.
2615 * We check this by iterating all dir items and checking if the inode behind
2616 * the dir item was already processed.
2617 */
2618static int can_rmdir(struct send_ctx *sctx, u64 dir, u64 send_progress)
2619{
2620 int ret = 0;
2621 struct btrfs_root *root = sctx->parent_root;
2622 struct btrfs_path *path;
2623 struct btrfs_key key;
2624 struct btrfs_key found_key;
2625 struct btrfs_key loc;
2626 struct btrfs_dir_item *di;
2627
Alexander Block6d85ed02012-08-01 14:48:59 +02002628 /*
2629 * Don't try to rmdir the top/root subvolume dir.
2630 */
2631 if (dir == BTRFS_FIRST_FREE_OBJECTID)
2632 return 0;
2633
Alexander Block31db9f72012-07-25 23:19:24 +02002634 path = alloc_path_for_send();
2635 if (!path)
2636 return -ENOMEM;
2637
2638 key.objectid = dir;
2639 key.type = BTRFS_DIR_INDEX_KEY;
2640 key.offset = 0;
2641
2642 while (1) {
2643 ret = btrfs_search_slot_for_read(root, &key, path, 1, 0);
2644 if (ret < 0)
2645 goto out;
2646 if (!ret) {
2647 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
2648 path->slots[0]);
2649 }
2650 if (ret || found_key.objectid != key.objectid ||
2651 found_key.type != key.type) {
2652 break;
2653 }
2654
2655 di = btrfs_item_ptr(path->nodes[0], path->slots[0],
2656 struct btrfs_dir_item);
2657 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &loc);
2658
2659 if (loc.objectid > send_progress) {
2660 ret = 0;
2661 goto out;
2662 }
2663
2664 btrfs_release_path(path);
2665 key.offset = found_key.offset + 1;
2666 }
2667
2668 ret = 1;
2669
2670out:
2671 btrfs_free_path(path);
2672 return ret;
2673}
2674
Alexander Block31db9f72012-07-25 23:19:24 +02002675/*
2676 * This does all the move/link/unlink/rmdir magic.
2677 */
2678static int process_recorded_refs(struct send_ctx *sctx)
2679{
2680 int ret = 0;
2681 struct recorded_ref *cur;
Alexander Block1f4692d2012-07-28 10:42:24 +02002682 struct recorded_ref *cur2;
Josef Bacikba5e8f22013-08-16 16:52:55 -04002683 struct list_head check_dirs;
Alexander Block31db9f72012-07-25 23:19:24 +02002684 struct fs_path *valid_path = NULL;
Chris Masonb24baf62012-07-25 19:21:10 -04002685 u64 ow_inode = 0;
Alexander Block31db9f72012-07-25 23:19:24 +02002686 u64 ow_gen;
2687 int did_overwrite = 0;
2688 int is_orphan = 0;
2689
2690verbose_printk("btrfs: process_recorded_refs %llu\n", sctx->cur_ino);
2691
Alexander Block6d85ed02012-08-01 14:48:59 +02002692 /*
2693 * This should never happen as the root dir always has the same ref
2694 * which is always '..'
2695 */
2696 BUG_ON(sctx->cur_ino <= BTRFS_FIRST_FREE_OBJECTID);
Josef Bacikba5e8f22013-08-16 16:52:55 -04002697 INIT_LIST_HEAD(&check_dirs);
Alexander Block6d85ed02012-08-01 14:48:59 +02002698
Tsutomu Itoh924794c2013-05-08 07:51:52 +00002699 valid_path = fs_path_alloc();
Alexander Block31db9f72012-07-25 23:19:24 +02002700 if (!valid_path) {
2701 ret = -ENOMEM;
2702 goto out;
2703 }
2704
Alexander Block31db9f72012-07-25 23:19:24 +02002705 /*
2706 * First, check if the first ref of the current inode was overwritten
2707 * before. If yes, we know that the current inode was already orphanized
2708 * and thus use the orphan name. If not, we can use get_cur_path to
2709 * get the path of the first ref as it would like while receiving at
2710 * this point in time.
2711 * New inodes are always orphan at the beginning, so force to use the
2712 * orphan name in this case.
2713 * The first ref is stored in valid_path and will be updated if it
2714 * gets moved around.
2715 */
2716 if (!sctx->cur_inode_new) {
2717 ret = did_overwrite_first_ref(sctx, sctx->cur_ino,
2718 sctx->cur_inode_gen);
2719 if (ret < 0)
2720 goto out;
2721 if (ret)
2722 did_overwrite = 1;
2723 }
2724 if (sctx->cur_inode_new || did_overwrite) {
2725 ret = gen_unique_name(sctx, sctx->cur_ino,
2726 sctx->cur_inode_gen, valid_path);
2727 if (ret < 0)
2728 goto out;
2729 is_orphan = 1;
2730 } else {
2731 ret = get_cur_path(sctx, sctx->cur_ino, sctx->cur_inode_gen,
2732 valid_path);
2733 if (ret < 0)
2734 goto out;
2735 }
2736
2737 list_for_each_entry(cur, &sctx->new_refs, list) {
2738 /*
Alexander Block1f4692d2012-07-28 10:42:24 +02002739 * We may have refs where the parent directory does not exist
2740 * yet. This happens if the parent directories inum is higher
2741 * the the current inum. To handle this case, we create the
2742 * parent directory out of order. But we need to check if this
2743 * did already happen before due to other refs in the same dir.
2744 */
2745 ret = get_cur_inode_state(sctx, cur->dir, cur->dir_gen);
2746 if (ret < 0)
2747 goto out;
2748 if (ret == inode_state_will_create) {
2749 ret = 0;
2750 /*
2751 * First check if any of the current inodes refs did
2752 * already create the dir.
2753 */
2754 list_for_each_entry(cur2, &sctx->new_refs, list) {
2755 if (cur == cur2)
2756 break;
2757 if (cur2->dir == cur->dir) {
2758 ret = 1;
2759 break;
2760 }
2761 }
2762
2763 /*
2764 * If that did not happen, check if a previous inode
2765 * did already create the dir.
2766 */
2767 if (!ret)
2768 ret = did_create_dir(sctx, cur->dir);
2769 if (ret < 0)
2770 goto out;
2771 if (!ret) {
2772 ret = send_create_inode(sctx, cur->dir);
2773 if (ret < 0)
2774 goto out;
2775 }
2776 }
2777
2778 /*
Alexander Block31db9f72012-07-25 23:19:24 +02002779 * Check if this new ref would overwrite the first ref of
2780 * another unprocessed inode. If yes, orphanize the
2781 * overwritten inode. If we find an overwritten ref that is
2782 * not the first ref, simply unlink it.
2783 */
2784 ret = will_overwrite_ref(sctx, cur->dir, cur->dir_gen,
2785 cur->name, cur->name_len,
2786 &ow_inode, &ow_gen);
2787 if (ret < 0)
2788 goto out;
2789 if (ret) {
Tsutomu Itoh924794c2013-05-08 07:51:52 +00002790 ret = is_first_ref(sctx->parent_root,
2791 ow_inode, cur->dir, cur->name,
2792 cur->name_len);
Alexander Block31db9f72012-07-25 23:19:24 +02002793 if (ret < 0)
2794 goto out;
2795 if (ret) {
2796 ret = orphanize_inode(sctx, ow_inode, ow_gen,
2797 cur->full_path);
2798 if (ret < 0)
2799 goto out;
2800 } else {
2801 ret = send_unlink(sctx, cur->full_path);
2802 if (ret < 0)
2803 goto out;
2804 }
2805 }
2806
2807 /*
2808 * link/move the ref to the new place. If we have an orphan
2809 * inode, move it and update valid_path. If not, link or move
2810 * it depending on the inode mode.
2811 */
Alexander Block1f4692d2012-07-28 10:42:24 +02002812 if (is_orphan) {
Alexander Block31db9f72012-07-25 23:19:24 +02002813 ret = send_rename(sctx, valid_path, cur->full_path);
2814 if (ret < 0)
2815 goto out;
2816 is_orphan = 0;
2817 ret = fs_path_copy(valid_path, cur->full_path);
2818 if (ret < 0)
2819 goto out;
2820 } else {
2821 if (S_ISDIR(sctx->cur_inode_mode)) {
2822 /*
2823 * Dirs can't be linked, so move it. For moved
2824 * dirs, we always have one new and one deleted
2825 * ref. The deleted ref is ignored later.
2826 */
2827 ret = send_rename(sctx, valid_path,
2828 cur->full_path);
2829 if (ret < 0)
2830 goto out;
2831 ret = fs_path_copy(valid_path, cur->full_path);
2832 if (ret < 0)
2833 goto out;
2834 } else {
2835 ret = send_link(sctx, cur->full_path,
2836 valid_path);
2837 if (ret < 0)
2838 goto out;
2839 }
2840 }
Josef Bacikba5e8f22013-08-16 16:52:55 -04002841 ret = dup_ref(cur, &check_dirs);
Alexander Block31db9f72012-07-25 23:19:24 +02002842 if (ret < 0)
2843 goto out;
2844 }
2845
2846 if (S_ISDIR(sctx->cur_inode_mode) && sctx->cur_inode_deleted) {
2847 /*
2848 * Check if we can already rmdir the directory. If not,
2849 * orphanize it. For every dir item inside that gets deleted
2850 * later, we do this check again and rmdir it then if possible.
2851 * See the use of check_dirs for more details.
2852 */
2853 ret = can_rmdir(sctx, sctx->cur_ino, sctx->cur_ino);
2854 if (ret < 0)
2855 goto out;
2856 if (ret) {
2857 ret = send_rmdir(sctx, valid_path);
2858 if (ret < 0)
2859 goto out;
2860 } else if (!is_orphan) {
2861 ret = orphanize_inode(sctx, sctx->cur_ino,
2862 sctx->cur_inode_gen, valid_path);
2863 if (ret < 0)
2864 goto out;
2865 is_orphan = 1;
2866 }
2867
2868 list_for_each_entry(cur, &sctx->deleted_refs, list) {
Josef Bacikba5e8f22013-08-16 16:52:55 -04002869 ret = dup_ref(cur, &check_dirs);
Alexander Block31db9f72012-07-25 23:19:24 +02002870 if (ret < 0)
2871 goto out;
2872 }
Alexander Blockccf16262012-07-28 11:46:29 +02002873 } else if (S_ISDIR(sctx->cur_inode_mode) &&
2874 !list_empty(&sctx->deleted_refs)) {
2875 /*
2876 * We have a moved dir. Add the old parent to check_dirs
2877 */
2878 cur = list_entry(sctx->deleted_refs.next, struct recorded_ref,
2879 list);
Josef Bacikba5e8f22013-08-16 16:52:55 -04002880 ret = dup_ref(cur, &check_dirs);
Alexander Blockccf16262012-07-28 11:46:29 +02002881 if (ret < 0)
2882 goto out;
Alexander Block31db9f72012-07-25 23:19:24 +02002883 } else if (!S_ISDIR(sctx->cur_inode_mode)) {
2884 /*
2885 * We have a non dir inode. Go through all deleted refs and
2886 * unlink them if they were not already overwritten by other
2887 * inodes.
2888 */
2889 list_for_each_entry(cur, &sctx->deleted_refs, list) {
2890 ret = did_overwrite_ref(sctx, cur->dir, cur->dir_gen,
2891 sctx->cur_ino, sctx->cur_inode_gen,
2892 cur->name, cur->name_len);
2893 if (ret < 0)
2894 goto out;
2895 if (!ret) {
Alexander Block1f4692d2012-07-28 10:42:24 +02002896 ret = send_unlink(sctx, cur->full_path);
2897 if (ret < 0)
2898 goto out;
Alexander Block31db9f72012-07-25 23:19:24 +02002899 }
Josef Bacikba5e8f22013-08-16 16:52:55 -04002900 ret = dup_ref(cur, &check_dirs);
Alexander Block31db9f72012-07-25 23:19:24 +02002901 if (ret < 0)
2902 goto out;
2903 }
Alexander Block31db9f72012-07-25 23:19:24 +02002904 /*
2905 * If the inode is still orphan, unlink the orphan. This may
2906 * happen when a previous inode did overwrite the first ref
2907 * of this inode and no new refs were added for the current
Alexander Block766702e2012-07-28 14:11:31 +02002908 * inode. Unlinking does not mean that the inode is deleted in
2909 * all cases. There may still be links to this inode in other
2910 * places.
Alexander Block31db9f72012-07-25 23:19:24 +02002911 */
Alexander Block1f4692d2012-07-28 10:42:24 +02002912 if (is_orphan) {
Alexander Block31db9f72012-07-25 23:19:24 +02002913 ret = send_unlink(sctx, valid_path);
2914 if (ret < 0)
2915 goto out;
2916 }
2917 }
2918
2919 /*
2920 * We did collect all parent dirs where cur_inode was once located. We
2921 * now go through all these dirs and check if they are pending for
2922 * deletion and if it's finally possible to perform the rmdir now.
2923 * We also update the inode stats of the parent dirs here.
2924 */
Josef Bacikba5e8f22013-08-16 16:52:55 -04002925 list_for_each_entry(cur, &check_dirs, list) {
Alexander Block766702e2012-07-28 14:11:31 +02002926 /*
2927 * In case we had refs into dirs that were not processed yet,
2928 * we don't need to do the utime and rmdir logic for these dirs.
2929 * The dir will be processed later.
2930 */
Josef Bacikba5e8f22013-08-16 16:52:55 -04002931 if (cur->dir > sctx->cur_ino)
Alexander Block31db9f72012-07-25 23:19:24 +02002932 continue;
2933
Josef Bacikba5e8f22013-08-16 16:52:55 -04002934 ret = get_cur_inode_state(sctx, cur->dir, cur->dir_gen);
Alexander Block31db9f72012-07-25 23:19:24 +02002935 if (ret < 0)
2936 goto out;
2937
2938 if (ret == inode_state_did_create ||
2939 ret == inode_state_no_change) {
2940 /* TODO delayed utimes */
Josef Bacikba5e8f22013-08-16 16:52:55 -04002941 ret = send_utimes(sctx, cur->dir, cur->dir_gen);
Alexander Block31db9f72012-07-25 23:19:24 +02002942 if (ret < 0)
2943 goto out;
2944 } else if (ret == inode_state_did_delete) {
Josef Bacikba5e8f22013-08-16 16:52:55 -04002945 ret = can_rmdir(sctx, cur->dir, sctx->cur_ino);
Alexander Block31db9f72012-07-25 23:19:24 +02002946 if (ret < 0)
2947 goto out;
2948 if (ret) {
Josef Bacikba5e8f22013-08-16 16:52:55 -04002949 ret = get_cur_path(sctx, cur->dir,
2950 cur->dir_gen, valid_path);
Alexander Block31db9f72012-07-25 23:19:24 +02002951 if (ret < 0)
2952 goto out;
2953 ret = send_rmdir(sctx, valid_path);
2954 if (ret < 0)
2955 goto out;
2956 }
2957 }
2958 }
2959
Alexander Block31db9f72012-07-25 23:19:24 +02002960 ret = 0;
2961
2962out:
Josef Bacikba5e8f22013-08-16 16:52:55 -04002963 __free_recorded_refs(&check_dirs);
Alexander Block31db9f72012-07-25 23:19:24 +02002964 free_recorded_refs(sctx);
Tsutomu Itoh924794c2013-05-08 07:51:52 +00002965 fs_path_free(valid_path);
Alexander Block31db9f72012-07-25 23:19:24 +02002966 return ret;
2967}
2968
2969static int __record_new_ref(int num, u64 dir, int index,
2970 struct fs_path *name,
2971 void *ctx)
2972{
2973 int ret = 0;
2974 struct send_ctx *sctx = ctx;
2975 struct fs_path *p;
2976 u64 gen;
2977
Tsutomu Itoh924794c2013-05-08 07:51:52 +00002978 p = fs_path_alloc();
Alexander Block31db9f72012-07-25 23:19:24 +02002979 if (!p)
2980 return -ENOMEM;
2981
2982 ret = get_inode_info(sctx->send_root, dir, NULL, &gen, NULL, NULL,
Alexander Block85a7b332012-07-26 23:39:10 +02002983 NULL, NULL);
Alexander Block31db9f72012-07-25 23:19:24 +02002984 if (ret < 0)
2985 goto out;
2986
Alexander Block31db9f72012-07-25 23:19:24 +02002987 ret = get_cur_path(sctx, dir, gen, p);
2988 if (ret < 0)
2989 goto out;
2990 ret = fs_path_add_path(p, name);
2991 if (ret < 0)
2992 goto out;
2993
2994 ret = record_ref(&sctx->new_refs, dir, gen, p);
2995
2996out:
2997 if (ret)
Tsutomu Itoh924794c2013-05-08 07:51:52 +00002998 fs_path_free(p);
Alexander Block31db9f72012-07-25 23:19:24 +02002999 return ret;
3000}
3001
3002static int __record_deleted_ref(int num, u64 dir, int index,
3003 struct fs_path *name,
3004 void *ctx)
3005{
3006 int ret = 0;
3007 struct send_ctx *sctx = ctx;
3008 struct fs_path *p;
3009 u64 gen;
3010
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003011 p = fs_path_alloc();
Alexander Block31db9f72012-07-25 23:19:24 +02003012 if (!p)
3013 return -ENOMEM;
3014
3015 ret = get_inode_info(sctx->parent_root, dir, NULL, &gen, NULL, NULL,
Alexander Block85a7b332012-07-26 23:39:10 +02003016 NULL, NULL);
Alexander Block31db9f72012-07-25 23:19:24 +02003017 if (ret < 0)
3018 goto out;
3019
3020 ret = get_cur_path(sctx, dir, gen, p);
3021 if (ret < 0)
3022 goto out;
3023 ret = fs_path_add_path(p, name);
3024 if (ret < 0)
3025 goto out;
3026
3027 ret = record_ref(&sctx->deleted_refs, dir, gen, p);
3028
3029out:
3030 if (ret)
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003031 fs_path_free(p);
Alexander Block31db9f72012-07-25 23:19:24 +02003032 return ret;
3033}
3034
3035static int record_new_ref(struct send_ctx *sctx)
3036{
3037 int ret;
3038
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003039 ret = iterate_inode_ref(sctx->send_root, sctx->left_path,
3040 sctx->cmp_key, 0, __record_new_ref, sctx);
Alexander Block31db9f72012-07-25 23:19:24 +02003041 if (ret < 0)
3042 goto out;
3043 ret = 0;
3044
3045out:
3046 return ret;
3047}
3048
3049static int record_deleted_ref(struct send_ctx *sctx)
3050{
3051 int ret;
3052
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003053 ret = iterate_inode_ref(sctx->parent_root, sctx->right_path,
3054 sctx->cmp_key, 0, __record_deleted_ref, sctx);
Alexander Block31db9f72012-07-25 23:19:24 +02003055 if (ret < 0)
3056 goto out;
3057 ret = 0;
3058
3059out:
3060 return ret;
3061}
3062
3063struct find_ref_ctx {
3064 u64 dir;
Josef Bacikba5e8f22013-08-16 16:52:55 -04003065 u64 dir_gen;
3066 struct btrfs_root *root;
Alexander Block31db9f72012-07-25 23:19:24 +02003067 struct fs_path *name;
3068 int found_idx;
3069};
3070
3071static int __find_iref(int num, u64 dir, int index,
3072 struct fs_path *name,
3073 void *ctx_)
3074{
3075 struct find_ref_ctx *ctx = ctx_;
Josef Bacikba5e8f22013-08-16 16:52:55 -04003076 u64 dir_gen;
3077 int ret;
Alexander Block31db9f72012-07-25 23:19:24 +02003078
3079 if (dir == ctx->dir && fs_path_len(name) == fs_path_len(ctx->name) &&
3080 strncmp(name->start, ctx->name->start, fs_path_len(name)) == 0) {
Josef Bacikba5e8f22013-08-16 16:52:55 -04003081 /*
3082 * To avoid doing extra lookups we'll only do this if everything
3083 * else matches.
3084 */
3085 ret = get_inode_info(ctx->root, dir, NULL, &dir_gen, NULL,
3086 NULL, NULL, NULL);
3087 if (ret)
3088 return ret;
3089 if (dir_gen != ctx->dir_gen)
3090 return 0;
Alexander Block31db9f72012-07-25 23:19:24 +02003091 ctx->found_idx = num;
3092 return 1;
3093 }
3094 return 0;
3095}
3096
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003097static int find_iref(struct btrfs_root *root,
Alexander Block31db9f72012-07-25 23:19:24 +02003098 struct btrfs_path *path,
3099 struct btrfs_key *key,
Josef Bacikba5e8f22013-08-16 16:52:55 -04003100 u64 dir, u64 dir_gen, struct fs_path *name)
Alexander Block31db9f72012-07-25 23:19:24 +02003101{
3102 int ret;
3103 struct find_ref_ctx ctx;
3104
3105 ctx.dir = dir;
3106 ctx.name = name;
Josef Bacikba5e8f22013-08-16 16:52:55 -04003107 ctx.dir_gen = dir_gen;
Alexander Block31db9f72012-07-25 23:19:24 +02003108 ctx.found_idx = -1;
Josef Bacikba5e8f22013-08-16 16:52:55 -04003109 ctx.root = root;
Alexander Block31db9f72012-07-25 23:19:24 +02003110
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003111 ret = iterate_inode_ref(root, path, key, 0, __find_iref, &ctx);
Alexander Block31db9f72012-07-25 23:19:24 +02003112 if (ret < 0)
3113 return ret;
3114
3115 if (ctx.found_idx == -1)
3116 return -ENOENT;
3117
3118 return ctx.found_idx;
3119}
3120
3121static int __record_changed_new_ref(int num, u64 dir, int index,
3122 struct fs_path *name,
3123 void *ctx)
3124{
Josef Bacikba5e8f22013-08-16 16:52:55 -04003125 u64 dir_gen;
Alexander Block31db9f72012-07-25 23:19:24 +02003126 int ret;
3127 struct send_ctx *sctx = ctx;
3128
Josef Bacikba5e8f22013-08-16 16:52:55 -04003129 ret = get_inode_info(sctx->send_root, dir, NULL, &dir_gen, NULL,
3130 NULL, NULL, NULL);
3131 if (ret)
3132 return ret;
3133
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003134 ret = find_iref(sctx->parent_root, sctx->right_path,
Josef Bacikba5e8f22013-08-16 16:52:55 -04003135 sctx->cmp_key, dir, dir_gen, name);
Alexander Block31db9f72012-07-25 23:19:24 +02003136 if (ret == -ENOENT)
3137 ret = __record_new_ref(num, dir, index, name, sctx);
3138 else if (ret > 0)
3139 ret = 0;
3140
3141 return ret;
3142}
3143
3144static int __record_changed_deleted_ref(int num, u64 dir, int index,
3145 struct fs_path *name,
3146 void *ctx)
3147{
Josef Bacikba5e8f22013-08-16 16:52:55 -04003148 u64 dir_gen;
Alexander Block31db9f72012-07-25 23:19:24 +02003149 int ret;
3150 struct send_ctx *sctx = ctx;
3151
Josef Bacikba5e8f22013-08-16 16:52:55 -04003152 ret = get_inode_info(sctx->parent_root, dir, NULL, &dir_gen, NULL,
3153 NULL, NULL, NULL);
3154 if (ret)
3155 return ret;
3156
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003157 ret = find_iref(sctx->send_root, sctx->left_path, sctx->cmp_key,
Josef Bacikba5e8f22013-08-16 16:52:55 -04003158 dir, dir_gen, name);
Alexander Block31db9f72012-07-25 23:19:24 +02003159 if (ret == -ENOENT)
3160 ret = __record_deleted_ref(num, dir, index, name, sctx);
3161 else if (ret > 0)
3162 ret = 0;
3163
3164 return ret;
3165}
3166
3167static int record_changed_ref(struct send_ctx *sctx)
3168{
3169 int ret = 0;
3170
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003171 ret = iterate_inode_ref(sctx->send_root, sctx->left_path,
Alexander Block31db9f72012-07-25 23:19:24 +02003172 sctx->cmp_key, 0, __record_changed_new_ref, sctx);
3173 if (ret < 0)
3174 goto out;
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003175 ret = iterate_inode_ref(sctx->parent_root, sctx->right_path,
Alexander Block31db9f72012-07-25 23:19:24 +02003176 sctx->cmp_key, 0, __record_changed_deleted_ref, sctx);
3177 if (ret < 0)
3178 goto out;
3179 ret = 0;
3180
3181out:
3182 return ret;
3183}
3184
3185/*
3186 * Record and process all refs at once. Needed when an inode changes the
3187 * generation number, which means that it was deleted and recreated.
3188 */
3189static int process_all_refs(struct send_ctx *sctx,
3190 enum btrfs_compare_tree_result cmd)
3191{
3192 int ret;
3193 struct btrfs_root *root;
3194 struct btrfs_path *path;
3195 struct btrfs_key key;
3196 struct btrfs_key found_key;
3197 struct extent_buffer *eb;
3198 int slot;
3199 iterate_inode_ref_t cb;
3200
3201 path = alloc_path_for_send();
3202 if (!path)
3203 return -ENOMEM;
3204
3205 if (cmd == BTRFS_COMPARE_TREE_NEW) {
3206 root = sctx->send_root;
3207 cb = __record_new_ref;
3208 } else if (cmd == BTRFS_COMPARE_TREE_DELETED) {
3209 root = sctx->parent_root;
3210 cb = __record_deleted_ref;
3211 } else {
3212 BUG();
3213 }
3214
3215 key.objectid = sctx->cmp_key->objectid;
3216 key.type = BTRFS_INODE_REF_KEY;
3217 key.offset = 0;
3218 while (1) {
3219 ret = btrfs_search_slot_for_read(root, &key, path, 1, 0);
Alexander Blocke938c8a2012-07-28 16:33:49 +02003220 if (ret < 0)
Alexander Block31db9f72012-07-25 23:19:24 +02003221 goto out;
Alexander Blocke938c8a2012-07-28 16:33:49 +02003222 if (ret)
Alexander Block31db9f72012-07-25 23:19:24 +02003223 break;
Alexander Block31db9f72012-07-25 23:19:24 +02003224
3225 eb = path->nodes[0];
3226 slot = path->slots[0];
3227 btrfs_item_key_to_cpu(eb, &found_key, slot);
3228
3229 if (found_key.objectid != key.objectid ||
Jan Schmidt96b5bd72012-10-15 08:30:45 +00003230 (found_key.type != BTRFS_INODE_REF_KEY &&
3231 found_key.type != BTRFS_INODE_EXTREF_KEY))
Alexander Block31db9f72012-07-25 23:19:24 +02003232 break;
Alexander Block31db9f72012-07-25 23:19:24 +02003233
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003234 ret = iterate_inode_ref(root, path, &found_key, 0, cb, sctx);
Alexander Block31db9f72012-07-25 23:19:24 +02003235 btrfs_release_path(path);
3236 if (ret < 0)
3237 goto out;
3238
3239 key.offset = found_key.offset + 1;
3240 }
Alexander Blocke938c8a2012-07-28 16:33:49 +02003241 btrfs_release_path(path);
Alexander Block31db9f72012-07-25 23:19:24 +02003242
3243 ret = process_recorded_refs(sctx);
3244
3245out:
3246 btrfs_free_path(path);
3247 return ret;
3248}
3249
3250static int send_set_xattr(struct send_ctx *sctx,
3251 struct fs_path *path,
3252 const char *name, int name_len,
3253 const char *data, int data_len)
3254{
3255 int ret = 0;
3256
3257 ret = begin_cmd(sctx, BTRFS_SEND_C_SET_XATTR);
3258 if (ret < 0)
3259 goto out;
3260
3261 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, path);
3262 TLV_PUT_STRING(sctx, BTRFS_SEND_A_XATTR_NAME, name, name_len);
3263 TLV_PUT(sctx, BTRFS_SEND_A_XATTR_DATA, data, data_len);
3264
3265 ret = send_cmd(sctx);
3266
3267tlv_put_failure:
3268out:
3269 return ret;
3270}
3271
3272static int send_remove_xattr(struct send_ctx *sctx,
3273 struct fs_path *path,
3274 const char *name, int name_len)
3275{
3276 int ret = 0;
3277
3278 ret = begin_cmd(sctx, BTRFS_SEND_C_REMOVE_XATTR);
3279 if (ret < 0)
3280 goto out;
3281
3282 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, path);
3283 TLV_PUT_STRING(sctx, BTRFS_SEND_A_XATTR_NAME, name, name_len);
3284
3285 ret = send_cmd(sctx);
3286
3287tlv_put_failure:
3288out:
3289 return ret;
3290}
3291
3292static int __process_new_xattr(int num, struct btrfs_key *di_key,
3293 const char *name, int name_len,
3294 const char *data, int data_len,
3295 u8 type, void *ctx)
3296{
3297 int ret;
3298 struct send_ctx *sctx = ctx;
3299 struct fs_path *p;
3300 posix_acl_xattr_header dummy_acl;
3301
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003302 p = fs_path_alloc();
Alexander Block31db9f72012-07-25 23:19:24 +02003303 if (!p)
3304 return -ENOMEM;
3305
3306 /*
3307 * This hack is needed because empty acl's are stored as zero byte
3308 * data in xattrs. Problem with that is, that receiving these zero byte
3309 * acl's will fail later. To fix this, we send a dummy acl list that
3310 * only contains the version number and no entries.
3311 */
3312 if (!strncmp(name, XATTR_NAME_POSIX_ACL_ACCESS, name_len) ||
3313 !strncmp(name, XATTR_NAME_POSIX_ACL_DEFAULT, name_len)) {
3314 if (data_len == 0) {
3315 dummy_acl.a_version =
3316 cpu_to_le32(POSIX_ACL_XATTR_VERSION);
3317 data = (char *)&dummy_acl;
3318 data_len = sizeof(dummy_acl);
3319 }
3320 }
3321
3322 ret = get_cur_path(sctx, sctx->cur_ino, sctx->cur_inode_gen, p);
3323 if (ret < 0)
3324 goto out;
3325
3326 ret = send_set_xattr(sctx, p, name, name_len, data, data_len);
3327
3328out:
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003329 fs_path_free(p);
Alexander Block31db9f72012-07-25 23:19:24 +02003330 return ret;
3331}
3332
3333static int __process_deleted_xattr(int num, struct btrfs_key *di_key,
3334 const char *name, int name_len,
3335 const char *data, int data_len,
3336 u8 type, void *ctx)
3337{
3338 int ret;
3339 struct send_ctx *sctx = ctx;
3340 struct fs_path *p;
3341
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003342 p = fs_path_alloc();
Alexander Block31db9f72012-07-25 23:19:24 +02003343 if (!p)
3344 return -ENOMEM;
3345
3346 ret = get_cur_path(sctx, sctx->cur_ino, sctx->cur_inode_gen, p);
3347 if (ret < 0)
3348 goto out;
3349
3350 ret = send_remove_xattr(sctx, p, name, name_len);
3351
3352out:
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003353 fs_path_free(p);
Alexander Block31db9f72012-07-25 23:19:24 +02003354 return ret;
3355}
3356
3357static int process_new_xattr(struct send_ctx *sctx)
3358{
3359 int ret = 0;
3360
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003361 ret = iterate_dir_item(sctx->send_root, sctx->left_path,
3362 sctx->cmp_key, __process_new_xattr, sctx);
Alexander Block31db9f72012-07-25 23:19:24 +02003363
3364 return ret;
3365}
3366
3367static int process_deleted_xattr(struct send_ctx *sctx)
3368{
3369 int ret;
3370
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003371 ret = iterate_dir_item(sctx->parent_root, sctx->right_path,
3372 sctx->cmp_key, __process_deleted_xattr, sctx);
Alexander Block31db9f72012-07-25 23:19:24 +02003373
3374 return ret;
3375}
3376
3377struct find_xattr_ctx {
3378 const char *name;
3379 int name_len;
3380 int found_idx;
3381 char *found_data;
3382 int found_data_len;
3383};
3384
3385static int __find_xattr(int num, struct btrfs_key *di_key,
3386 const char *name, int name_len,
3387 const char *data, int data_len,
3388 u8 type, void *vctx)
3389{
3390 struct find_xattr_ctx *ctx = vctx;
3391
3392 if (name_len == ctx->name_len &&
3393 strncmp(name, ctx->name, name_len) == 0) {
3394 ctx->found_idx = num;
3395 ctx->found_data_len = data_len;
Thomas Meyera5959bc2013-06-01 09:37:50 +00003396 ctx->found_data = kmemdup(data, data_len, GFP_NOFS);
Alexander Block31db9f72012-07-25 23:19:24 +02003397 if (!ctx->found_data)
3398 return -ENOMEM;
Alexander Block31db9f72012-07-25 23:19:24 +02003399 return 1;
3400 }
3401 return 0;
3402}
3403
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003404static int find_xattr(struct btrfs_root *root,
Alexander Block31db9f72012-07-25 23:19:24 +02003405 struct btrfs_path *path,
3406 struct btrfs_key *key,
3407 const char *name, int name_len,
3408 char **data, int *data_len)
3409{
3410 int ret;
3411 struct find_xattr_ctx ctx;
3412
3413 ctx.name = name;
3414 ctx.name_len = name_len;
3415 ctx.found_idx = -1;
3416 ctx.found_data = NULL;
3417 ctx.found_data_len = 0;
3418
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003419 ret = iterate_dir_item(root, path, key, __find_xattr, &ctx);
Alexander Block31db9f72012-07-25 23:19:24 +02003420 if (ret < 0)
3421 return ret;
3422
3423 if (ctx.found_idx == -1)
3424 return -ENOENT;
3425 if (data) {
3426 *data = ctx.found_data;
3427 *data_len = ctx.found_data_len;
3428 } else {
3429 kfree(ctx.found_data);
3430 }
3431 return ctx.found_idx;
3432}
3433
3434
3435static int __process_changed_new_xattr(int num, struct btrfs_key *di_key,
3436 const char *name, int name_len,
3437 const char *data, int data_len,
3438 u8 type, void *ctx)
3439{
3440 int ret;
3441 struct send_ctx *sctx = ctx;
3442 char *found_data = NULL;
3443 int found_data_len = 0;
Alexander Block31db9f72012-07-25 23:19:24 +02003444
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003445 ret = find_xattr(sctx->parent_root, sctx->right_path,
3446 sctx->cmp_key, name, name_len, &found_data,
3447 &found_data_len);
Alexander Block31db9f72012-07-25 23:19:24 +02003448 if (ret == -ENOENT) {
3449 ret = __process_new_xattr(num, di_key, name, name_len, data,
3450 data_len, type, ctx);
3451 } else if (ret >= 0) {
3452 if (data_len != found_data_len ||
3453 memcmp(data, found_data, data_len)) {
3454 ret = __process_new_xattr(num, di_key, name, name_len,
3455 data, data_len, type, ctx);
3456 } else {
3457 ret = 0;
3458 }
3459 }
3460
3461 kfree(found_data);
Alexander Block31db9f72012-07-25 23:19:24 +02003462 return ret;
3463}
3464
3465static int __process_changed_deleted_xattr(int num, struct btrfs_key *di_key,
3466 const char *name, int name_len,
3467 const char *data, int data_len,
3468 u8 type, void *ctx)
3469{
3470 int ret;
3471 struct send_ctx *sctx = ctx;
3472
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003473 ret = find_xattr(sctx->send_root, sctx->left_path, sctx->cmp_key,
3474 name, name_len, NULL, NULL);
Alexander Block31db9f72012-07-25 23:19:24 +02003475 if (ret == -ENOENT)
3476 ret = __process_deleted_xattr(num, di_key, name, name_len, data,
3477 data_len, type, ctx);
3478 else if (ret >= 0)
3479 ret = 0;
3480
3481 return ret;
3482}
3483
3484static int process_changed_xattr(struct send_ctx *sctx)
3485{
3486 int ret = 0;
3487
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003488 ret = iterate_dir_item(sctx->send_root, sctx->left_path,
Alexander Block31db9f72012-07-25 23:19:24 +02003489 sctx->cmp_key, __process_changed_new_xattr, sctx);
3490 if (ret < 0)
3491 goto out;
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003492 ret = iterate_dir_item(sctx->parent_root, sctx->right_path,
Alexander Block31db9f72012-07-25 23:19:24 +02003493 sctx->cmp_key, __process_changed_deleted_xattr, sctx);
3494
3495out:
3496 return ret;
3497}
3498
3499static int process_all_new_xattrs(struct send_ctx *sctx)
3500{
3501 int ret;
3502 struct btrfs_root *root;
3503 struct btrfs_path *path;
3504 struct btrfs_key key;
3505 struct btrfs_key found_key;
3506 struct extent_buffer *eb;
3507 int slot;
3508
3509 path = alloc_path_for_send();
3510 if (!path)
3511 return -ENOMEM;
3512
3513 root = sctx->send_root;
3514
3515 key.objectid = sctx->cmp_key->objectid;
3516 key.type = BTRFS_XATTR_ITEM_KEY;
3517 key.offset = 0;
3518 while (1) {
3519 ret = btrfs_search_slot_for_read(root, &key, path, 1, 0);
3520 if (ret < 0)
3521 goto out;
3522 if (ret) {
3523 ret = 0;
3524 goto out;
3525 }
3526
3527 eb = path->nodes[0];
3528 slot = path->slots[0];
3529 btrfs_item_key_to_cpu(eb, &found_key, slot);
3530
3531 if (found_key.objectid != key.objectid ||
3532 found_key.type != key.type) {
3533 ret = 0;
3534 goto out;
3535 }
3536
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003537 ret = iterate_dir_item(root, path, &found_key,
3538 __process_new_xattr, sctx);
Alexander Block31db9f72012-07-25 23:19:24 +02003539 if (ret < 0)
3540 goto out;
3541
3542 btrfs_release_path(path);
3543 key.offset = found_key.offset + 1;
3544 }
3545
3546out:
3547 btrfs_free_path(path);
3548 return ret;
3549}
3550
Josef Baciked259092013-10-25 11:36:01 -04003551static ssize_t fill_read_buf(struct send_ctx *sctx, u64 offset, u32 len)
3552{
3553 struct btrfs_root *root = sctx->send_root;
3554 struct btrfs_fs_info *fs_info = root->fs_info;
3555 struct inode *inode;
3556 struct page *page;
3557 char *addr;
3558 struct btrfs_key key;
3559 pgoff_t index = offset >> PAGE_CACHE_SHIFT;
3560 pgoff_t last_index;
3561 unsigned pg_offset = offset & ~PAGE_CACHE_MASK;
3562 ssize_t ret = 0;
3563
3564 key.objectid = sctx->cur_ino;
3565 key.type = BTRFS_INODE_ITEM_KEY;
3566 key.offset = 0;
3567
3568 inode = btrfs_iget(fs_info->sb, &key, root, NULL);
3569 if (IS_ERR(inode))
3570 return PTR_ERR(inode);
3571
3572 if (offset + len > i_size_read(inode)) {
3573 if (offset > i_size_read(inode))
3574 len = 0;
3575 else
3576 len = offset - i_size_read(inode);
3577 }
3578 if (len == 0)
3579 goto out;
3580
3581 last_index = (offset + len - 1) >> PAGE_CACHE_SHIFT;
3582 while (index <= last_index) {
3583 unsigned cur_len = min_t(unsigned, len,
3584 PAGE_CACHE_SIZE - pg_offset);
3585 page = find_or_create_page(inode->i_mapping, index, GFP_NOFS);
3586 if (!page) {
3587 ret = -ENOMEM;
3588 break;
3589 }
3590
3591 if (!PageUptodate(page)) {
3592 btrfs_readpage(NULL, page);
3593 lock_page(page);
3594 if (!PageUptodate(page)) {
3595 unlock_page(page);
3596 page_cache_release(page);
3597 ret = -EIO;
3598 break;
3599 }
3600 }
3601
3602 addr = kmap(page);
3603 memcpy(sctx->read_buf + ret, addr + pg_offset, cur_len);
3604 kunmap(page);
3605 unlock_page(page);
3606 page_cache_release(page);
3607 index++;
3608 pg_offset = 0;
3609 len -= cur_len;
3610 ret += cur_len;
3611 }
3612out:
3613 iput(inode);
3614 return ret;
3615}
3616
Alexander Block31db9f72012-07-25 23:19:24 +02003617/*
3618 * Read some bytes from the current inode/file and send a write command to
3619 * user space.
3620 */
3621static int send_write(struct send_ctx *sctx, u64 offset, u32 len)
3622{
3623 int ret = 0;
3624 struct fs_path *p;
Josef Baciked259092013-10-25 11:36:01 -04003625 ssize_t num_read = 0;
Alexander Block31db9f72012-07-25 23:19:24 +02003626
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003627 p = fs_path_alloc();
Alexander Block31db9f72012-07-25 23:19:24 +02003628 if (!p)
3629 return -ENOMEM;
3630
Alexander Block31db9f72012-07-25 23:19:24 +02003631verbose_printk("btrfs: send_write offset=%llu, len=%d\n", offset, len);
3632
Josef Baciked259092013-10-25 11:36:01 -04003633 num_read = fill_read_buf(sctx, offset, len);
3634 if (num_read <= 0) {
3635 if (num_read < 0)
3636 ret = num_read;
Alexander Block31db9f72012-07-25 23:19:24 +02003637 goto out;
Josef Baciked259092013-10-25 11:36:01 -04003638 }
Alexander Block31db9f72012-07-25 23:19:24 +02003639
3640 ret = begin_cmd(sctx, BTRFS_SEND_C_WRITE);
3641 if (ret < 0)
3642 goto out;
3643
3644 ret = get_cur_path(sctx, sctx->cur_ino, sctx->cur_inode_gen, p);
3645 if (ret < 0)
3646 goto out;
3647
3648 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, p);
3649 TLV_PUT_U64(sctx, BTRFS_SEND_A_FILE_OFFSET, offset);
Alexander Blocke938c8a2012-07-28 16:33:49 +02003650 TLV_PUT(sctx, BTRFS_SEND_A_DATA, sctx->read_buf, num_read);
Alexander Block31db9f72012-07-25 23:19:24 +02003651
3652 ret = send_cmd(sctx);
3653
3654tlv_put_failure:
3655out:
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003656 fs_path_free(p);
Alexander Block31db9f72012-07-25 23:19:24 +02003657 if (ret < 0)
3658 return ret;
Alexander Blocke938c8a2012-07-28 16:33:49 +02003659 return num_read;
Alexander Block31db9f72012-07-25 23:19:24 +02003660}
3661
3662/*
3663 * Send a clone command to user space.
3664 */
3665static int send_clone(struct send_ctx *sctx,
3666 u64 offset, u32 len,
3667 struct clone_root *clone_root)
3668{
3669 int ret = 0;
Alexander Block31db9f72012-07-25 23:19:24 +02003670 struct fs_path *p;
3671 u64 gen;
3672
3673verbose_printk("btrfs: send_clone offset=%llu, len=%d, clone_root=%llu, "
3674 "clone_inode=%llu, clone_offset=%llu\n", offset, len,
3675 clone_root->root->objectid, clone_root->ino,
3676 clone_root->offset);
3677
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003678 p = fs_path_alloc();
Alexander Block31db9f72012-07-25 23:19:24 +02003679 if (!p)
3680 return -ENOMEM;
3681
3682 ret = begin_cmd(sctx, BTRFS_SEND_C_CLONE);
3683 if (ret < 0)
3684 goto out;
3685
3686 ret = get_cur_path(sctx, sctx->cur_ino, sctx->cur_inode_gen, p);
3687 if (ret < 0)
3688 goto out;
3689
3690 TLV_PUT_U64(sctx, BTRFS_SEND_A_FILE_OFFSET, offset);
3691 TLV_PUT_U64(sctx, BTRFS_SEND_A_CLONE_LEN, len);
3692 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, p);
3693
Alexander Blocke938c8a2012-07-28 16:33:49 +02003694 if (clone_root->root == sctx->send_root) {
Alexander Block31db9f72012-07-25 23:19:24 +02003695 ret = get_inode_info(sctx->send_root, clone_root->ino, NULL,
Alexander Block85a7b332012-07-26 23:39:10 +02003696 &gen, NULL, NULL, NULL, NULL);
Alexander Block31db9f72012-07-25 23:19:24 +02003697 if (ret < 0)
3698 goto out;
3699 ret = get_cur_path(sctx, clone_root->ino, gen, p);
3700 } else {
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003701 ret = get_inode_path(clone_root->root, clone_root->ino, p);
Alexander Block31db9f72012-07-25 23:19:24 +02003702 }
3703 if (ret < 0)
3704 goto out;
3705
3706 TLV_PUT_UUID(sctx, BTRFS_SEND_A_CLONE_UUID,
Alexander Blocke938c8a2012-07-28 16:33:49 +02003707 clone_root->root->root_item.uuid);
Alexander Block31db9f72012-07-25 23:19:24 +02003708 TLV_PUT_U64(sctx, BTRFS_SEND_A_CLONE_CTRANSID,
Alexander Blocke938c8a2012-07-28 16:33:49 +02003709 clone_root->root->root_item.ctransid);
Alexander Block31db9f72012-07-25 23:19:24 +02003710 TLV_PUT_PATH(sctx, BTRFS_SEND_A_CLONE_PATH, p);
3711 TLV_PUT_U64(sctx, BTRFS_SEND_A_CLONE_OFFSET,
3712 clone_root->offset);
3713
3714 ret = send_cmd(sctx);
3715
3716tlv_put_failure:
3717out:
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003718 fs_path_free(p);
Alexander Block31db9f72012-07-25 23:19:24 +02003719 return ret;
3720}
3721
Mark Fashehcb95e7b2013-02-04 20:54:57 +00003722/*
3723 * Send an update extent command to user space.
3724 */
3725static int send_update_extent(struct send_ctx *sctx,
3726 u64 offset, u32 len)
3727{
3728 int ret = 0;
3729 struct fs_path *p;
3730
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003731 p = fs_path_alloc();
Mark Fashehcb95e7b2013-02-04 20:54:57 +00003732 if (!p)
3733 return -ENOMEM;
3734
3735 ret = begin_cmd(sctx, BTRFS_SEND_C_UPDATE_EXTENT);
3736 if (ret < 0)
3737 goto out;
3738
3739 ret = get_cur_path(sctx, sctx->cur_ino, sctx->cur_inode_gen, p);
3740 if (ret < 0)
3741 goto out;
3742
3743 TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, p);
3744 TLV_PUT_U64(sctx, BTRFS_SEND_A_FILE_OFFSET, offset);
3745 TLV_PUT_U64(sctx, BTRFS_SEND_A_SIZE, len);
3746
3747 ret = send_cmd(sctx);
3748
3749tlv_put_failure:
3750out:
Tsutomu Itoh924794c2013-05-08 07:51:52 +00003751 fs_path_free(p);
Mark Fashehcb95e7b2013-02-04 20:54:57 +00003752 return ret;
3753}
3754
Alexander Block31db9f72012-07-25 23:19:24 +02003755static int send_write_or_clone(struct send_ctx *sctx,
3756 struct btrfs_path *path,
3757 struct btrfs_key *key,
3758 struct clone_root *clone_root)
3759{
3760 int ret = 0;
3761 struct btrfs_file_extent_item *ei;
3762 u64 offset = key->offset;
3763 u64 pos = 0;
3764 u64 len;
3765 u32 l;
3766 u8 type;
3767
3768 ei = btrfs_item_ptr(path->nodes[0], path->slots[0],
3769 struct btrfs_file_extent_item);
3770 type = btrfs_file_extent_type(path->nodes[0], ei);
Chris Mason74dd17f2012-08-07 16:25:13 -04003771 if (type == BTRFS_FILE_EXTENT_INLINE) {
Alexander Block31db9f72012-07-25 23:19:24 +02003772 len = btrfs_file_extent_inline_len(path->nodes[0], ei);
Chris Mason74dd17f2012-08-07 16:25:13 -04003773 /*
3774 * it is possible the inline item won't cover the whole page,
3775 * but there may be items after this page. Make
3776 * sure to send the whole thing
3777 */
3778 len = PAGE_CACHE_ALIGN(len);
3779 } else {
Alexander Block31db9f72012-07-25 23:19:24 +02003780 len = btrfs_file_extent_num_bytes(path->nodes[0], ei);
Chris Mason74dd17f2012-08-07 16:25:13 -04003781 }
Alexander Block31db9f72012-07-25 23:19:24 +02003782
3783 if (offset + len > sctx->cur_inode_size)
3784 len = sctx->cur_inode_size - offset;
3785 if (len == 0) {
3786 ret = 0;
3787 goto out;
3788 }
3789
Mark Fashehcb95e7b2013-02-04 20:54:57 +00003790 if (clone_root) {
3791 ret = send_clone(sctx, offset, len, clone_root);
3792 } else if (sctx->flags & BTRFS_SEND_FLAG_NO_FILE_DATA) {
3793 ret = send_update_extent(sctx, offset, len);
3794 } else {
Alexander Block31db9f72012-07-25 23:19:24 +02003795 while (pos < len) {
3796 l = len - pos;
3797 if (l > BTRFS_SEND_READ_SIZE)
3798 l = BTRFS_SEND_READ_SIZE;
3799 ret = send_write(sctx, pos + offset, l);
3800 if (ret < 0)
3801 goto out;
3802 if (!ret)
3803 break;
3804 pos += ret;
3805 }
3806 ret = 0;
Alexander Block31db9f72012-07-25 23:19:24 +02003807 }
Alexander Block31db9f72012-07-25 23:19:24 +02003808out:
3809 return ret;
3810}
3811
3812static int is_extent_unchanged(struct send_ctx *sctx,
3813 struct btrfs_path *left_path,
3814 struct btrfs_key *ekey)
3815{
3816 int ret = 0;
3817 struct btrfs_key key;
3818 struct btrfs_path *path = NULL;
3819 struct extent_buffer *eb;
3820 int slot;
3821 struct btrfs_key found_key;
3822 struct btrfs_file_extent_item *ei;
3823 u64 left_disknr;
3824 u64 right_disknr;
3825 u64 left_offset;
3826 u64 right_offset;
3827 u64 left_offset_fixed;
3828 u64 left_len;
3829 u64 right_len;
Chris Mason74dd17f2012-08-07 16:25:13 -04003830 u64 left_gen;
3831 u64 right_gen;
Alexander Block31db9f72012-07-25 23:19:24 +02003832 u8 left_type;
3833 u8 right_type;
3834
3835 path = alloc_path_for_send();
3836 if (!path)
3837 return -ENOMEM;
3838
3839 eb = left_path->nodes[0];
3840 slot = left_path->slots[0];
Alexander Block31db9f72012-07-25 23:19:24 +02003841 ei = btrfs_item_ptr(eb, slot, struct btrfs_file_extent_item);
3842 left_type = btrfs_file_extent_type(eb, ei);
Alexander Block31db9f72012-07-25 23:19:24 +02003843
3844 if (left_type != BTRFS_FILE_EXTENT_REG) {
3845 ret = 0;
3846 goto out;
3847 }
Chris Mason74dd17f2012-08-07 16:25:13 -04003848 left_disknr = btrfs_file_extent_disk_bytenr(eb, ei);
3849 left_len = btrfs_file_extent_num_bytes(eb, ei);
3850 left_offset = btrfs_file_extent_offset(eb, ei);
3851 left_gen = btrfs_file_extent_generation(eb, ei);
Alexander Block31db9f72012-07-25 23:19:24 +02003852
3853 /*
3854 * Following comments will refer to these graphics. L is the left
3855 * extents which we are checking at the moment. 1-8 are the right
3856 * extents that we iterate.
3857 *
3858 * |-----L-----|
3859 * |-1-|-2a-|-3-|-4-|-5-|-6-|
3860 *
3861 * |-----L-----|
3862 * |--1--|-2b-|...(same as above)
3863 *
3864 * Alternative situation. Happens on files where extents got split.
3865 * |-----L-----|
3866 * |-----------7-----------|-6-|
3867 *
3868 * Alternative situation. Happens on files which got larger.
3869 * |-----L-----|
3870 * |-8-|
3871 * Nothing follows after 8.
3872 */
3873
3874 key.objectid = ekey->objectid;
3875 key.type = BTRFS_EXTENT_DATA_KEY;
3876 key.offset = ekey->offset;
3877 ret = btrfs_search_slot_for_read(sctx->parent_root, &key, path, 0, 0);
3878 if (ret < 0)
3879 goto out;
3880 if (ret) {
3881 ret = 0;
3882 goto out;
3883 }
3884
3885 /*
3886 * Handle special case where the right side has no extents at all.
3887 */
3888 eb = path->nodes[0];
3889 slot = path->slots[0];
3890 btrfs_item_key_to_cpu(eb, &found_key, slot);
3891 if (found_key.objectid != key.objectid ||
3892 found_key.type != key.type) {
Josef Bacik57cfd462013-08-20 15:55:39 -04003893 /* If we're a hole then just pretend nothing changed */
3894 ret = (left_disknr) ? 0 : 1;
Alexander Block31db9f72012-07-25 23:19:24 +02003895 goto out;
3896 }
3897
3898 /*
3899 * We're now on 2a, 2b or 7.
3900 */
3901 key = found_key;
3902 while (key.offset < ekey->offset + left_len) {
3903 ei = btrfs_item_ptr(eb, slot, struct btrfs_file_extent_item);
3904 right_type = btrfs_file_extent_type(eb, ei);
Alexander Block31db9f72012-07-25 23:19:24 +02003905 if (right_type != BTRFS_FILE_EXTENT_REG) {
3906 ret = 0;
3907 goto out;
3908 }
3909
Josef Bacik007d31f2013-10-31 16:49:02 -04003910 right_disknr = btrfs_file_extent_disk_bytenr(eb, ei);
3911 right_len = btrfs_file_extent_num_bytes(eb, ei);
3912 right_offset = btrfs_file_extent_offset(eb, ei);
3913 right_gen = btrfs_file_extent_generation(eb, ei);
3914
Alexander Block31db9f72012-07-25 23:19:24 +02003915 /*
3916 * Are we at extent 8? If yes, we know the extent is changed.
3917 * This may only happen on the first iteration.
3918 */
Alexander Blockd8347fa2012-08-01 12:49:15 +02003919 if (found_key.offset + right_len <= ekey->offset) {
Josef Bacik57cfd462013-08-20 15:55:39 -04003920 /* If we're a hole just pretend nothing changed */
3921 ret = (left_disknr) ? 0 : 1;
Alexander Block31db9f72012-07-25 23:19:24 +02003922 goto out;
3923 }
3924
3925 left_offset_fixed = left_offset;
3926 if (key.offset < ekey->offset) {
3927 /* Fix the right offset for 2a and 7. */
3928 right_offset += ekey->offset - key.offset;
3929 } else {
3930 /* Fix the left offset for all behind 2a and 2b */
3931 left_offset_fixed += key.offset - ekey->offset;
3932 }
3933
3934 /*
3935 * Check if we have the same extent.
3936 */
Alexander Block39540962012-08-01 12:46:05 +02003937 if (left_disknr != right_disknr ||
Chris Mason74dd17f2012-08-07 16:25:13 -04003938 left_offset_fixed != right_offset ||
3939 left_gen != right_gen) {
Alexander Block31db9f72012-07-25 23:19:24 +02003940 ret = 0;
3941 goto out;
3942 }
3943
3944 /*
3945 * Go to the next extent.
3946 */
3947 ret = btrfs_next_item(sctx->parent_root, path);
3948 if (ret < 0)
3949 goto out;
3950 if (!ret) {
3951 eb = path->nodes[0];
3952 slot = path->slots[0];
3953 btrfs_item_key_to_cpu(eb, &found_key, slot);
3954 }
3955 if (ret || found_key.objectid != key.objectid ||
3956 found_key.type != key.type) {
3957 key.offset += right_len;
3958 break;
Jan Schmidtadaa4b82013-03-21 14:30:23 +00003959 }
3960 if (found_key.offset != key.offset + right_len) {
3961 ret = 0;
3962 goto out;
Alexander Block31db9f72012-07-25 23:19:24 +02003963 }
3964 key = found_key;
3965 }
3966
3967 /*
3968 * We're now behind the left extent (treat as unchanged) or at the end
3969 * of the right side (treat as changed).
3970 */
3971 if (key.offset >= ekey->offset + left_len)
3972 ret = 1;
3973 else
3974 ret = 0;
3975
3976
3977out:
3978 btrfs_free_path(path);
3979 return ret;
3980}
3981
3982static int process_extent(struct send_ctx *sctx,
3983 struct btrfs_path *path,
3984 struct btrfs_key *key)
3985{
Alexander Block31db9f72012-07-25 23:19:24 +02003986 struct clone_root *found_clone = NULL;
Josef Bacik57cfd462013-08-20 15:55:39 -04003987 int ret = 0;
Alexander Block31db9f72012-07-25 23:19:24 +02003988
3989 if (S_ISLNK(sctx->cur_inode_mode))
3990 return 0;
3991
3992 if (sctx->parent_root && !sctx->cur_inode_new) {
3993 ret = is_extent_unchanged(sctx, path, key);
3994 if (ret < 0)
3995 goto out;
3996 if (ret) {
3997 ret = 0;
3998 goto out;
3999 }
Josef Bacik57cfd462013-08-20 15:55:39 -04004000 } else {
4001 struct btrfs_file_extent_item *ei;
4002 u8 type;
4003
4004 ei = btrfs_item_ptr(path->nodes[0], path->slots[0],
4005 struct btrfs_file_extent_item);
4006 type = btrfs_file_extent_type(path->nodes[0], ei);
4007 if (type == BTRFS_FILE_EXTENT_PREALLOC ||
4008 type == BTRFS_FILE_EXTENT_REG) {
4009 /*
4010 * The send spec does not have a prealloc command yet,
4011 * so just leave a hole for prealloc'ed extents until
4012 * we have enough commands queued up to justify rev'ing
4013 * the send spec.
4014 */
4015 if (type == BTRFS_FILE_EXTENT_PREALLOC) {
4016 ret = 0;
4017 goto out;
4018 }
4019
4020 /* Have a hole, just skip it. */
4021 if (btrfs_file_extent_disk_bytenr(path->nodes[0], ei) == 0) {
4022 ret = 0;
4023 goto out;
4024 }
4025 }
Alexander Block31db9f72012-07-25 23:19:24 +02004026 }
4027
4028 ret = find_extent_clone(sctx, path, key->objectid, key->offset,
4029 sctx->cur_inode_size, &found_clone);
4030 if (ret != -ENOENT && ret < 0)
4031 goto out;
4032
4033 ret = send_write_or_clone(sctx, path, key, found_clone);
4034
4035out:
4036 return ret;
4037}
4038
4039static int process_all_extents(struct send_ctx *sctx)
4040{
4041 int ret;
4042 struct btrfs_root *root;
4043 struct btrfs_path *path;
4044 struct btrfs_key key;
4045 struct btrfs_key found_key;
4046 struct extent_buffer *eb;
4047 int slot;
4048
4049 root = sctx->send_root;
4050 path = alloc_path_for_send();
4051 if (!path)
4052 return -ENOMEM;
4053
4054 key.objectid = sctx->cmp_key->objectid;
4055 key.type = BTRFS_EXTENT_DATA_KEY;
4056 key.offset = 0;
4057 while (1) {
4058 ret = btrfs_search_slot_for_read(root, &key, path, 1, 0);
4059 if (ret < 0)
4060 goto out;
4061 if (ret) {
4062 ret = 0;
4063 goto out;
4064 }
4065
4066 eb = path->nodes[0];
4067 slot = path->slots[0];
4068 btrfs_item_key_to_cpu(eb, &found_key, slot);
4069
4070 if (found_key.objectid != key.objectid ||
4071 found_key.type != key.type) {
4072 ret = 0;
4073 goto out;
4074 }
4075
4076 ret = process_extent(sctx, path, &found_key);
4077 if (ret < 0)
4078 goto out;
4079
4080 btrfs_release_path(path);
4081 key.offset = found_key.offset + 1;
4082 }
4083
4084out:
4085 btrfs_free_path(path);
4086 return ret;
4087}
4088
4089static int process_recorded_refs_if_needed(struct send_ctx *sctx, int at_end)
4090{
4091 int ret = 0;
4092
4093 if (sctx->cur_ino == 0)
4094 goto out;
4095 if (!at_end && sctx->cur_ino == sctx->cmp_key->objectid &&
Jan Schmidt96b5bd72012-10-15 08:30:45 +00004096 sctx->cmp_key->type <= BTRFS_INODE_EXTREF_KEY)
Alexander Block31db9f72012-07-25 23:19:24 +02004097 goto out;
4098 if (list_empty(&sctx->new_refs) && list_empty(&sctx->deleted_refs))
4099 goto out;
4100
4101 ret = process_recorded_refs(sctx);
Alexander Blocke479d9b2012-07-28 16:09:35 +02004102 if (ret < 0)
4103 goto out;
4104
4105 /*
4106 * We have processed the refs and thus need to advance send_progress.
4107 * Now, calls to get_cur_xxx will take the updated refs of the current
4108 * inode into account.
4109 */
4110 sctx->send_progress = sctx->cur_ino + 1;
Alexander Block31db9f72012-07-25 23:19:24 +02004111
4112out:
4113 return ret;
4114}
4115
4116static int finish_inode_if_needed(struct send_ctx *sctx, int at_end)
4117{
4118 int ret = 0;
4119 u64 left_mode;
4120 u64 left_uid;
4121 u64 left_gid;
4122 u64 right_mode;
4123 u64 right_uid;
4124 u64 right_gid;
4125 int need_chmod = 0;
4126 int need_chown = 0;
4127
4128 ret = process_recorded_refs_if_needed(sctx, at_end);
4129 if (ret < 0)
4130 goto out;
4131
4132 if (sctx->cur_ino == 0 || sctx->cur_inode_deleted)
4133 goto out;
4134 if (!at_end && sctx->cmp_key->objectid == sctx->cur_ino)
4135 goto out;
4136
4137 ret = get_inode_info(sctx->send_root, sctx->cur_ino, NULL, NULL,
Alexander Block85a7b332012-07-26 23:39:10 +02004138 &left_mode, &left_uid, &left_gid, NULL);
Alexander Block31db9f72012-07-25 23:19:24 +02004139 if (ret < 0)
4140 goto out;
4141
Alex Lyakase2d044f2012-10-17 13:52:47 +00004142 if (!sctx->parent_root || sctx->cur_inode_new) {
4143 need_chown = 1;
4144 if (!S_ISLNK(sctx->cur_inode_mode))
Alexander Block31db9f72012-07-25 23:19:24 +02004145 need_chmod = 1;
Alex Lyakase2d044f2012-10-17 13:52:47 +00004146 } else {
4147 ret = get_inode_info(sctx->parent_root, sctx->cur_ino,
4148 NULL, NULL, &right_mode, &right_uid,
4149 &right_gid, NULL);
4150 if (ret < 0)
4151 goto out;
Alexander Block31db9f72012-07-25 23:19:24 +02004152
Alex Lyakase2d044f2012-10-17 13:52:47 +00004153 if (left_uid != right_uid || left_gid != right_gid)
4154 need_chown = 1;
4155 if (!S_ISLNK(sctx->cur_inode_mode) && left_mode != right_mode)
4156 need_chmod = 1;
Alexander Block31db9f72012-07-25 23:19:24 +02004157 }
4158
4159 if (S_ISREG(sctx->cur_inode_mode)) {
4160 ret = send_truncate(sctx, sctx->cur_ino, sctx->cur_inode_gen,
4161 sctx->cur_inode_size);
4162 if (ret < 0)
4163 goto out;
4164 }
4165
4166 if (need_chown) {
4167 ret = send_chown(sctx, sctx->cur_ino, sctx->cur_inode_gen,
4168 left_uid, left_gid);
4169 if (ret < 0)
4170 goto out;
4171 }
4172 if (need_chmod) {
4173 ret = send_chmod(sctx, sctx->cur_ino, sctx->cur_inode_gen,
4174 left_mode);
4175 if (ret < 0)
4176 goto out;
4177 }
4178
4179 /*
4180 * Need to send that every time, no matter if it actually changed
4181 * between the two trees as we have done changes to the inode before.
4182 */
4183 ret = send_utimes(sctx, sctx->cur_ino, sctx->cur_inode_gen);
4184 if (ret < 0)
4185 goto out;
4186
4187out:
4188 return ret;
4189}
4190
4191static int changed_inode(struct send_ctx *sctx,
4192 enum btrfs_compare_tree_result result)
4193{
4194 int ret = 0;
4195 struct btrfs_key *key = sctx->cmp_key;
4196 struct btrfs_inode_item *left_ii = NULL;
4197 struct btrfs_inode_item *right_ii = NULL;
4198 u64 left_gen = 0;
4199 u64 right_gen = 0;
4200
Alexander Block31db9f72012-07-25 23:19:24 +02004201 sctx->cur_ino = key->objectid;
4202 sctx->cur_inode_new_gen = 0;
Alexander Blocke479d9b2012-07-28 16:09:35 +02004203
4204 /*
4205 * Set send_progress to current inode. This will tell all get_cur_xxx
4206 * functions that the current inode's refs are not updated yet. Later,
4207 * when process_recorded_refs is finished, it is set to cur_ino + 1.
4208 */
Alexander Block31db9f72012-07-25 23:19:24 +02004209 sctx->send_progress = sctx->cur_ino;
4210
4211 if (result == BTRFS_COMPARE_TREE_NEW ||
4212 result == BTRFS_COMPARE_TREE_CHANGED) {
4213 left_ii = btrfs_item_ptr(sctx->left_path->nodes[0],
4214 sctx->left_path->slots[0],
4215 struct btrfs_inode_item);
4216 left_gen = btrfs_inode_generation(sctx->left_path->nodes[0],
4217 left_ii);
4218 } else {
4219 right_ii = btrfs_item_ptr(sctx->right_path->nodes[0],
4220 sctx->right_path->slots[0],
4221 struct btrfs_inode_item);
4222 right_gen = btrfs_inode_generation(sctx->right_path->nodes[0],
4223 right_ii);
4224 }
4225 if (result == BTRFS_COMPARE_TREE_CHANGED) {
4226 right_ii = btrfs_item_ptr(sctx->right_path->nodes[0],
4227 sctx->right_path->slots[0],
4228 struct btrfs_inode_item);
4229
4230 right_gen = btrfs_inode_generation(sctx->right_path->nodes[0],
4231 right_ii);
Alexander Block6d85ed02012-08-01 14:48:59 +02004232
4233 /*
4234 * The cur_ino = root dir case is special here. We can't treat
4235 * the inode as deleted+reused because it would generate a
4236 * stream that tries to delete/mkdir the root dir.
4237 */
4238 if (left_gen != right_gen &&
4239 sctx->cur_ino != BTRFS_FIRST_FREE_OBJECTID)
Alexander Block31db9f72012-07-25 23:19:24 +02004240 sctx->cur_inode_new_gen = 1;
4241 }
4242
4243 if (result == BTRFS_COMPARE_TREE_NEW) {
4244 sctx->cur_inode_gen = left_gen;
4245 sctx->cur_inode_new = 1;
4246 sctx->cur_inode_deleted = 0;
4247 sctx->cur_inode_size = btrfs_inode_size(
4248 sctx->left_path->nodes[0], left_ii);
4249 sctx->cur_inode_mode = btrfs_inode_mode(
4250 sctx->left_path->nodes[0], left_ii);
4251 if (sctx->cur_ino != BTRFS_FIRST_FREE_OBJECTID)
Alexander Block1f4692d2012-07-28 10:42:24 +02004252 ret = send_create_inode_if_needed(sctx);
Alexander Block31db9f72012-07-25 23:19:24 +02004253 } else if (result == BTRFS_COMPARE_TREE_DELETED) {
4254 sctx->cur_inode_gen = right_gen;
4255 sctx->cur_inode_new = 0;
4256 sctx->cur_inode_deleted = 1;
4257 sctx->cur_inode_size = btrfs_inode_size(
4258 sctx->right_path->nodes[0], right_ii);
4259 sctx->cur_inode_mode = btrfs_inode_mode(
4260 sctx->right_path->nodes[0], right_ii);
4261 } else if (result == BTRFS_COMPARE_TREE_CHANGED) {
Alexander Block766702e2012-07-28 14:11:31 +02004262 /*
4263 * We need to do some special handling in case the inode was
4264 * reported as changed with a changed generation number. This
4265 * means that the original inode was deleted and new inode
4266 * reused the same inum. So we have to treat the old inode as
4267 * deleted and the new one as new.
4268 */
Alexander Block31db9f72012-07-25 23:19:24 +02004269 if (sctx->cur_inode_new_gen) {
Alexander Block766702e2012-07-28 14:11:31 +02004270 /*
4271 * First, process the inode as if it was deleted.
4272 */
Alexander Block31db9f72012-07-25 23:19:24 +02004273 sctx->cur_inode_gen = right_gen;
4274 sctx->cur_inode_new = 0;
4275 sctx->cur_inode_deleted = 1;
4276 sctx->cur_inode_size = btrfs_inode_size(
4277 sctx->right_path->nodes[0], right_ii);
4278 sctx->cur_inode_mode = btrfs_inode_mode(
4279 sctx->right_path->nodes[0], right_ii);
4280 ret = process_all_refs(sctx,
4281 BTRFS_COMPARE_TREE_DELETED);
4282 if (ret < 0)
4283 goto out;
4284
Alexander Block766702e2012-07-28 14:11:31 +02004285 /*
4286 * Now process the inode as if it was new.
4287 */
Alexander Block31db9f72012-07-25 23:19:24 +02004288 sctx->cur_inode_gen = left_gen;
4289 sctx->cur_inode_new = 1;
4290 sctx->cur_inode_deleted = 0;
4291 sctx->cur_inode_size = btrfs_inode_size(
4292 sctx->left_path->nodes[0], left_ii);
4293 sctx->cur_inode_mode = btrfs_inode_mode(
4294 sctx->left_path->nodes[0], left_ii);
Alexander Block1f4692d2012-07-28 10:42:24 +02004295 ret = send_create_inode_if_needed(sctx);
Alexander Block31db9f72012-07-25 23:19:24 +02004296 if (ret < 0)
4297 goto out;
4298
4299 ret = process_all_refs(sctx, BTRFS_COMPARE_TREE_NEW);
4300 if (ret < 0)
4301 goto out;
Alexander Blocke479d9b2012-07-28 16:09:35 +02004302 /*
4303 * Advance send_progress now as we did not get into
4304 * process_recorded_refs_if_needed in the new_gen case.
4305 */
4306 sctx->send_progress = sctx->cur_ino + 1;
Alexander Block766702e2012-07-28 14:11:31 +02004307
4308 /*
4309 * Now process all extents and xattrs of the inode as if
4310 * they were all new.
4311 */
Alexander Block31db9f72012-07-25 23:19:24 +02004312 ret = process_all_extents(sctx);
4313 if (ret < 0)
4314 goto out;
4315 ret = process_all_new_xattrs(sctx);
4316 if (ret < 0)
4317 goto out;
4318 } else {
4319 sctx->cur_inode_gen = left_gen;
4320 sctx->cur_inode_new = 0;
4321 sctx->cur_inode_new_gen = 0;
4322 sctx->cur_inode_deleted = 0;
4323 sctx->cur_inode_size = btrfs_inode_size(
4324 sctx->left_path->nodes[0], left_ii);
4325 sctx->cur_inode_mode = btrfs_inode_mode(
4326 sctx->left_path->nodes[0], left_ii);
4327 }
4328 }
4329
4330out:
4331 return ret;
4332}
4333
Alexander Block766702e2012-07-28 14:11:31 +02004334/*
4335 * We have to process new refs before deleted refs, but compare_trees gives us
4336 * the new and deleted refs mixed. To fix this, we record the new/deleted refs
4337 * first and later process them in process_recorded_refs.
4338 * For the cur_inode_new_gen case, we skip recording completely because
4339 * changed_inode did already initiate processing of refs. The reason for this is
4340 * that in this case, compare_tree actually compares the refs of 2 different
4341 * inodes. To fix this, process_all_refs is used in changed_inode to handle all
4342 * refs of the right tree as deleted and all refs of the left tree as new.
4343 */
Alexander Block31db9f72012-07-25 23:19:24 +02004344static int changed_ref(struct send_ctx *sctx,
4345 enum btrfs_compare_tree_result result)
4346{
4347 int ret = 0;
4348
4349 BUG_ON(sctx->cur_ino != sctx->cmp_key->objectid);
4350
4351 if (!sctx->cur_inode_new_gen &&
4352 sctx->cur_ino != BTRFS_FIRST_FREE_OBJECTID) {
4353 if (result == BTRFS_COMPARE_TREE_NEW)
4354 ret = record_new_ref(sctx);
4355 else if (result == BTRFS_COMPARE_TREE_DELETED)
4356 ret = record_deleted_ref(sctx);
4357 else if (result == BTRFS_COMPARE_TREE_CHANGED)
4358 ret = record_changed_ref(sctx);
4359 }
4360
4361 return ret;
4362}
4363
Alexander Block766702e2012-07-28 14:11:31 +02004364/*
4365 * Process new/deleted/changed xattrs. We skip processing in the
4366 * cur_inode_new_gen case because changed_inode did already initiate processing
4367 * of xattrs. The reason is the same as in changed_ref
4368 */
Alexander Block31db9f72012-07-25 23:19:24 +02004369static int changed_xattr(struct send_ctx *sctx,
4370 enum btrfs_compare_tree_result result)
4371{
4372 int ret = 0;
4373
4374 BUG_ON(sctx->cur_ino != sctx->cmp_key->objectid);
4375
4376 if (!sctx->cur_inode_new_gen && !sctx->cur_inode_deleted) {
4377 if (result == BTRFS_COMPARE_TREE_NEW)
4378 ret = process_new_xattr(sctx);
4379 else if (result == BTRFS_COMPARE_TREE_DELETED)
4380 ret = process_deleted_xattr(sctx);
4381 else if (result == BTRFS_COMPARE_TREE_CHANGED)
4382 ret = process_changed_xattr(sctx);
4383 }
4384
4385 return ret;
4386}
4387
Alexander Block766702e2012-07-28 14:11:31 +02004388/*
4389 * Process new/deleted/changed extents. We skip processing in the
4390 * cur_inode_new_gen case because changed_inode did already initiate processing
4391 * of extents. The reason is the same as in changed_ref
4392 */
Alexander Block31db9f72012-07-25 23:19:24 +02004393static int changed_extent(struct send_ctx *sctx,
4394 enum btrfs_compare_tree_result result)
4395{
4396 int ret = 0;
4397
4398 BUG_ON(sctx->cur_ino != sctx->cmp_key->objectid);
4399
4400 if (!sctx->cur_inode_new_gen && !sctx->cur_inode_deleted) {
4401 if (result != BTRFS_COMPARE_TREE_DELETED)
4402 ret = process_extent(sctx, sctx->left_path,
4403 sctx->cmp_key);
4404 }
4405
4406 return ret;
4407}
4408
Josef Bacikba5e8f22013-08-16 16:52:55 -04004409static int dir_changed(struct send_ctx *sctx, u64 dir)
4410{
4411 u64 orig_gen, new_gen;
4412 int ret;
4413
4414 ret = get_inode_info(sctx->send_root, dir, NULL, &new_gen, NULL, NULL,
4415 NULL, NULL);
4416 if (ret)
4417 return ret;
4418
4419 ret = get_inode_info(sctx->parent_root, dir, NULL, &orig_gen, NULL,
4420 NULL, NULL, NULL);
4421 if (ret)
4422 return ret;
4423
4424 return (orig_gen != new_gen) ? 1 : 0;
4425}
4426
4427static int compare_refs(struct send_ctx *sctx, struct btrfs_path *path,
4428 struct btrfs_key *key)
4429{
4430 struct btrfs_inode_extref *extref;
4431 struct extent_buffer *leaf;
4432 u64 dirid = 0, last_dirid = 0;
4433 unsigned long ptr;
4434 u32 item_size;
4435 u32 cur_offset = 0;
4436 int ref_name_len;
4437 int ret = 0;
4438
4439 /* Easy case, just check this one dirid */
4440 if (key->type == BTRFS_INODE_REF_KEY) {
4441 dirid = key->offset;
4442
4443 ret = dir_changed(sctx, dirid);
4444 goto out;
4445 }
4446
4447 leaf = path->nodes[0];
4448 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
4449 ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
4450 while (cur_offset < item_size) {
4451 extref = (struct btrfs_inode_extref *)(ptr +
4452 cur_offset);
4453 dirid = btrfs_inode_extref_parent(leaf, extref);
4454 ref_name_len = btrfs_inode_extref_name_len(leaf, extref);
4455 cur_offset += ref_name_len + sizeof(*extref);
4456 if (dirid == last_dirid)
4457 continue;
4458 ret = dir_changed(sctx, dirid);
4459 if (ret)
4460 break;
4461 last_dirid = dirid;
4462 }
4463out:
4464 return ret;
4465}
4466
Alexander Block766702e2012-07-28 14:11:31 +02004467/*
4468 * Updates compare related fields in sctx and simply forwards to the actual
4469 * changed_xxx functions.
4470 */
Alexander Block31db9f72012-07-25 23:19:24 +02004471static int changed_cb(struct btrfs_root *left_root,
4472 struct btrfs_root *right_root,
4473 struct btrfs_path *left_path,
4474 struct btrfs_path *right_path,
4475 struct btrfs_key *key,
4476 enum btrfs_compare_tree_result result,
4477 void *ctx)
4478{
4479 int ret = 0;
4480 struct send_ctx *sctx = ctx;
4481
Josef Bacikba5e8f22013-08-16 16:52:55 -04004482 if (result == BTRFS_COMPARE_TREE_SAME) {
4483 if (key->type != BTRFS_INODE_REF_KEY &&
4484 key->type != BTRFS_INODE_EXTREF_KEY)
4485 return 0;
4486 ret = compare_refs(sctx, left_path, key);
4487 if (!ret)
4488 return 0;
4489 if (ret < 0)
4490 return ret;
4491 result = BTRFS_COMPARE_TREE_CHANGED;
4492 ret = 0;
4493 }
4494
Alexander Block31db9f72012-07-25 23:19:24 +02004495 sctx->left_path = left_path;
4496 sctx->right_path = right_path;
4497 sctx->cmp_key = key;
4498
4499 ret = finish_inode_if_needed(sctx, 0);
4500 if (ret < 0)
4501 goto out;
4502
Alexander Block2981e222012-08-01 14:47:03 +02004503 /* Ignore non-FS objects */
4504 if (key->objectid == BTRFS_FREE_INO_OBJECTID ||
4505 key->objectid == BTRFS_FREE_SPACE_OBJECTID)
4506 goto out;
4507
Alexander Block31db9f72012-07-25 23:19:24 +02004508 if (key->type == BTRFS_INODE_ITEM_KEY)
4509 ret = changed_inode(sctx, result);
Jan Schmidt96b5bd72012-10-15 08:30:45 +00004510 else if (key->type == BTRFS_INODE_REF_KEY ||
4511 key->type == BTRFS_INODE_EXTREF_KEY)
Alexander Block31db9f72012-07-25 23:19:24 +02004512 ret = changed_ref(sctx, result);
4513 else if (key->type == BTRFS_XATTR_ITEM_KEY)
4514 ret = changed_xattr(sctx, result);
4515 else if (key->type == BTRFS_EXTENT_DATA_KEY)
4516 ret = changed_extent(sctx, result);
4517
4518out:
4519 return ret;
4520}
4521
4522static int full_send_tree(struct send_ctx *sctx)
4523{
4524 int ret;
4525 struct btrfs_trans_handle *trans = NULL;
4526 struct btrfs_root *send_root = sctx->send_root;
4527 struct btrfs_key key;
4528 struct btrfs_key found_key;
4529 struct btrfs_path *path;
4530 struct extent_buffer *eb;
4531 int slot;
4532 u64 start_ctransid;
4533 u64 ctransid;
4534
4535 path = alloc_path_for_send();
4536 if (!path)
4537 return -ENOMEM;
4538
Anand Jain5f3ab902012-12-07 09:28:54 +00004539 spin_lock(&send_root->root_item_lock);
Alexander Block31db9f72012-07-25 23:19:24 +02004540 start_ctransid = btrfs_root_ctransid(&send_root->root_item);
Anand Jain5f3ab902012-12-07 09:28:54 +00004541 spin_unlock(&send_root->root_item_lock);
Alexander Block31db9f72012-07-25 23:19:24 +02004542
4543 key.objectid = BTRFS_FIRST_FREE_OBJECTID;
4544 key.type = BTRFS_INODE_ITEM_KEY;
4545 key.offset = 0;
4546
4547join_trans:
4548 /*
4549 * We need to make sure the transaction does not get committed
4550 * while we do anything on commit roots. Join a transaction to prevent
4551 * this.
4552 */
4553 trans = btrfs_join_transaction(send_root);
4554 if (IS_ERR(trans)) {
4555 ret = PTR_ERR(trans);
4556 trans = NULL;
4557 goto out;
4558 }
4559
4560 /*
Alexander Block766702e2012-07-28 14:11:31 +02004561 * Make sure the tree has not changed after re-joining. We detect this
4562 * by comparing start_ctransid and ctransid. They should always match.
Alexander Block31db9f72012-07-25 23:19:24 +02004563 */
Anand Jain5f3ab902012-12-07 09:28:54 +00004564 spin_lock(&send_root->root_item_lock);
Alexander Block31db9f72012-07-25 23:19:24 +02004565 ctransid = btrfs_root_ctransid(&send_root->root_item);
Anand Jain5f3ab902012-12-07 09:28:54 +00004566 spin_unlock(&send_root->root_item_lock);
Alexander Block31db9f72012-07-25 23:19:24 +02004567
4568 if (ctransid != start_ctransid) {
4569 WARN(1, KERN_WARNING "btrfs: the root that you're trying to "
4570 "send was modified in between. This is "
4571 "probably a bug.\n");
4572 ret = -EIO;
4573 goto out;
4574 }
4575
4576 ret = btrfs_search_slot_for_read(send_root, &key, path, 1, 0);
4577 if (ret < 0)
4578 goto out;
4579 if (ret)
4580 goto out_finish;
4581
4582 while (1) {
4583 /*
4584 * When someone want to commit while we iterate, end the
4585 * joined transaction and rejoin.
4586 */
4587 if (btrfs_should_end_transaction(trans, send_root)) {
4588 ret = btrfs_end_transaction(trans, send_root);
4589 trans = NULL;
4590 if (ret < 0)
4591 goto out;
4592 btrfs_release_path(path);
4593 goto join_trans;
4594 }
4595
4596 eb = path->nodes[0];
4597 slot = path->slots[0];
4598 btrfs_item_key_to_cpu(eb, &found_key, slot);
4599
4600 ret = changed_cb(send_root, NULL, path, NULL,
4601 &found_key, BTRFS_COMPARE_TREE_NEW, sctx);
4602 if (ret < 0)
4603 goto out;
4604
4605 key.objectid = found_key.objectid;
4606 key.type = found_key.type;
4607 key.offset = found_key.offset + 1;
4608
4609 ret = btrfs_next_item(send_root, path);
4610 if (ret < 0)
4611 goto out;
4612 if (ret) {
4613 ret = 0;
4614 break;
4615 }
4616 }
4617
4618out_finish:
4619 ret = finish_inode_if_needed(sctx, 1);
4620
4621out:
4622 btrfs_free_path(path);
4623 if (trans) {
4624 if (!ret)
4625 ret = btrfs_end_transaction(trans, send_root);
4626 else
4627 btrfs_end_transaction(trans, send_root);
4628 }
4629 return ret;
4630}
4631
4632static int send_subvol(struct send_ctx *sctx)
4633{
4634 int ret;
4635
Stefan Behrensc2c71322013-04-10 17:10:52 +00004636 if (!(sctx->flags & BTRFS_SEND_FLAG_OMIT_STREAM_HEADER)) {
4637 ret = send_header(sctx);
4638 if (ret < 0)
4639 goto out;
4640 }
Alexander Block31db9f72012-07-25 23:19:24 +02004641
4642 ret = send_subvol_begin(sctx);
4643 if (ret < 0)
4644 goto out;
4645
4646 if (sctx->parent_root) {
4647 ret = btrfs_compare_trees(sctx->send_root, sctx->parent_root,
4648 changed_cb, sctx);
4649 if (ret < 0)
4650 goto out;
4651 ret = finish_inode_if_needed(sctx, 1);
4652 if (ret < 0)
4653 goto out;
4654 } else {
4655 ret = full_send_tree(sctx);
4656 if (ret < 0)
4657 goto out;
4658 }
4659
4660out:
Alexander Block31db9f72012-07-25 23:19:24 +02004661 free_recorded_refs(sctx);
4662 return ret;
4663}
4664
4665long btrfs_ioctl_send(struct file *mnt_file, void __user *arg_)
4666{
4667 int ret = 0;
4668 struct btrfs_root *send_root;
4669 struct btrfs_root *clone_root;
4670 struct btrfs_fs_info *fs_info;
4671 struct btrfs_ioctl_send_args *arg = NULL;
4672 struct btrfs_key key;
Alexander Block31db9f72012-07-25 23:19:24 +02004673 struct send_ctx *sctx = NULL;
4674 u32 i;
4675 u64 *clone_sources_tmp = NULL;
4676
4677 if (!capable(CAP_SYS_ADMIN))
4678 return -EPERM;
4679
Al Viro496ad9a2013-01-23 17:07:38 -05004680 send_root = BTRFS_I(file_inode(mnt_file))->root;
Alexander Block31db9f72012-07-25 23:19:24 +02004681 fs_info = send_root->fs_info;
4682
Josef Bacik139f8072013-05-20 11:26:50 -04004683 /*
4684 * This is done when we lookup the root, it should already be complete
4685 * by the time we get here.
4686 */
4687 WARN_ON(send_root->orphan_cleanup_state != ORPHAN_CLEANUP_DONE);
4688
4689 /*
4690 * If we just created this root we need to make sure that the orphan
4691 * cleanup has been done and committed since we search the commit root,
4692 * so check its commit root transid with our otransid and if they match
4693 * commit the transaction to make sure everything is updated.
4694 */
4695 down_read(&send_root->fs_info->extent_commit_sem);
4696 if (btrfs_header_generation(send_root->commit_root) ==
4697 btrfs_root_otransid(&send_root->root_item)) {
4698 struct btrfs_trans_handle *trans;
4699
4700 up_read(&send_root->fs_info->extent_commit_sem);
4701
4702 trans = btrfs_attach_transaction_barrier(send_root);
4703 if (IS_ERR(trans)) {
4704 if (PTR_ERR(trans) != -ENOENT) {
4705 ret = PTR_ERR(trans);
4706 goto out;
4707 }
4708 /* ENOENT means theres no transaction */
4709 } else {
4710 ret = btrfs_commit_transaction(trans, send_root);
4711 if (ret)
4712 goto out;
4713 }
4714 } else {
4715 up_read(&send_root->fs_info->extent_commit_sem);
4716 }
4717
Alexander Block31db9f72012-07-25 23:19:24 +02004718 arg = memdup_user(arg_, sizeof(*arg));
4719 if (IS_ERR(arg)) {
4720 ret = PTR_ERR(arg);
4721 arg = NULL;
4722 goto out;
4723 }
4724
4725 if (!access_ok(VERIFY_READ, arg->clone_sources,
Dan Carpenter700ff4f2013-01-10 03:57:25 -05004726 sizeof(*arg->clone_sources) *
4727 arg->clone_sources_count)) {
Alexander Block31db9f72012-07-25 23:19:24 +02004728 ret = -EFAULT;
4729 goto out;
4730 }
4731
Stefan Behrensc2c71322013-04-10 17:10:52 +00004732 if (arg->flags & ~BTRFS_SEND_FLAG_MASK) {
Mark Fashehcb95e7b2013-02-04 20:54:57 +00004733 ret = -EINVAL;
4734 goto out;
4735 }
4736
Alexander Block31db9f72012-07-25 23:19:24 +02004737 sctx = kzalloc(sizeof(struct send_ctx), GFP_NOFS);
4738 if (!sctx) {
4739 ret = -ENOMEM;
4740 goto out;
4741 }
4742
4743 INIT_LIST_HEAD(&sctx->new_refs);
4744 INIT_LIST_HEAD(&sctx->deleted_refs);
4745 INIT_RADIX_TREE(&sctx->name_cache, GFP_NOFS);
4746 INIT_LIST_HEAD(&sctx->name_cache_list);
4747
Mark Fashehcb95e7b2013-02-04 20:54:57 +00004748 sctx->flags = arg->flags;
4749
Alexander Block31db9f72012-07-25 23:19:24 +02004750 sctx->send_filp = fget(arg->send_fd);
Tsutomu Itohecc7ada2013-04-19 01:04:46 +00004751 if (!sctx->send_filp) {
4752 ret = -EBADF;
Alexander Block31db9f72012-07-25 23:19:24 +02004753 goto out;
4754 }
4755
4756 sctx->mnt = mnt_file->f_path.mnt;
4757
4758 sctx->send_root = send_root;
4759 sctx->clone_roots_cnt = arg->clone_sources_count;
4760
4761 sctx->send_max_size = BTRFS_SEND_BUF_SIZE;
4762 sctx->send_buf = vmalloc(sctx->send_max_size);
4763 if (!sctx->send_buf) {
4764 ret = -ENOMEM;
4765 goto out;
4766 }
4767
4768 sctx->read_buf = vmalloc(BTRFS_SEND_READ_SIZE);
4769 if (!sctx->read_buf) {
4770 ret = -ENOMEM;
4771 goto out;
4772 }
4773
4774 sctx->clone_roots = vzalloc(sizeof(struct clone_root) *
4775 (arg->clone_sources_count + 1));
4776 if (!sctx->clone_roots) {
4777 ret = -ENOMEM;
4778 goto out;
4779 }
4780
4781 if (arg->clone_sources_count) {
4782 clone_sources_tmp = vmalloc(arg->clone_sources_count *
4783 sizeof(*arg->clone_sources));
4784 if (!clone_sources_tmp) {
4785 ret = -ENOMEM;
4786 goto out;
4787 }
4788
4789 ret = copy_from_user(clone_sources_tmp, arg->clone_sources,
4790 arg->clone_sources_count *
4791 sizeof(*arg->clone_sources));
4792 if (ret) {
4793 ret = -EFAULT;
4794 goto out;
4795 }
4796
4797 for (i = 0; i < arg->clone_sources_count; i++) {
4798 key.objectid = clone_sources_tmp[i];
4799 key.type = BTRFS_ROOT_ITEM_KEY;
4800 key.offset = (u64)-1;
4801 clone_root = btrfs_read_fs_root_no_name(fs_info, &key);
Alexander Block31db9f72012-07-25 23:19:24 +02004802 if (IS_ERR(clone_root)) {
4803 ret = PTR_ERR(clone_root);
4804 goto out;
4805 }
4806 sctx->clone_roots[i].root = clone_root;
4807 }
4808 vfree(clone_sources_tmp);
4809 clone_sources_tmp = NULL;
4810 }
4811
4812 if (arg->parent_root) {
4813 key.objectid = arg->parent_root;
4814 key.type = BTRFS_ROOT_ITEM_KEY;
4815 key.offset = (u64)-1;
4816 sctx->parent_root = btrfs_read_fs_root_no_name(fs_info, &key);
Stefan Behrensb1b19592013-05-13 14:42:57 +00004817 if (IS_ERR(sctx->parent_root)) {
4818 ret = PTR_ERR(sctx->parent_root);
Alexander Block31db9f72012-07-25 23:19:24 +02004819 goto out;
4820 }
4821 }
4822
4823 /*
4824 * Clones from send_root are allowed, but only if the clone source
4825 * is behind the current send position. This is checked while searching
4826 * for possible clone sources.
4827 */
4828 sctx->clone_roots[sctx->clone_roots_cnt++].root = sctx->send_root;
4829
4830 /* We do a bsearch later */
4831 sort(sctx->clone_roots, sctx->clone_roots_cnt,
4832 sizeof(*sctx->clone_roots), __clone_root_cmp_sort,
4833 NULL);
4834
4835 ret = send_subvol(sctx);
4836 if (ret < 0)
4837 goto out;
4838
Stefan Behrensc2c71322013-04-10 17:10:52 +00004839 if (!(sctx->flags & BTRFS_SEND_FLAG_OMIT_END_CMD)) {
4840 ret = begin_cmd(sctx, BTRFS_SEND_C_END);
4841 if (ret < 0)
4842 goto out;
4843 ret = send_cmd(sctx);
4844 if (ret < 0)
4845 goto out;
4846 }
Alexander Block31db9f72012-07-25 23:19:24 +02004847
4848out:
Alexander Block31db9f72012-07-25 23:19:24 +02004849 kfree(arg);
4850 vfree(clone_sources_tmp);
4851
4852 if (sctx) {
4853 if (sctx->send_filp)
4854 fput(sctx->send_filp);
4855
4856 vfree(sctx->clone_roots);
4857 vfree(sctx->send_buf);
4858 vfree(sctx->read_buf);
4859
4860 name_cache_free(sctx);
4861
4862 kfree(sctx);
4863 }
4864
4865 return ret;
4866}