2 * Copyright (C) 2012 Alexander Block. All rights reserved.
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.
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.
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.
19 #include <linux/bsearch.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>
28 #include <linux/vmalloc.h>
29 #include <linux/string.h>
35 #include "btrfs_inode.h"
36 #include "transaction.h"
38 static int g_verbose
= 0;
40 #define verbose_printk(...) if (g_verbose) printk(__VA_ARGS__)
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.
58 unsigned int reversed
:1;
59 unsigned int virtual_mem
:1;
65 #define FS_PATH_INLINE_SIZE \
66 (sizeof(struct fs_path) - offsetof(struct fs_path, inline_buf))
69 /* reused for each extent */
71 struct btrfs_root
*root
;
78 #define SEND_CTX_MAX_NAME_CACHE_SIZE 128
79 #define SEND_CTX_NAME_CACHE_CLEAN_SIZE (SEND_CTX_MAX_NAME_CACHE_SIZE * 2)
82 struct file
*send_filp
;
88 u64 cmd_send_size
[BTRFS_SEND_C_MAX
+ 1];
89 u64 flags
; /* 'flags' member of btrfs_ioctl_send_args is u64 */
93 struct btrfs_root
*send_root
;
94 struct btrfs_root
*parent_root
;
95 struct clone_root
*clone_roots
;
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
;
104 * infos of the currently processed inode. In case of deleted inodes,
105 * these are the values from the deleted inode.
110 int cur_inode_new_gen
;
111 int cur_inode_deleted
;
117 struct list_head new_refs
;
118 struct list_head deleted_refs
;
120 struct radix_tree_root name_cache
;
121 struct list_head name_cache_list
;
127 struct name_cache_entry
{
128 struct list_head list
;
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
137 struct list_head radix_list
;
143 int need_later_update
;
148 static void fs_path_reset(struct fs_path
*p
)
151 p
->start
= p
->buf
+ p
->buf_len
- 1;
161 static struct fs_path
*fs_path_alloc(void)
165 p
= kmalloc(sizeof(*p
), GFP_NOFS
);
170 p
->buf
= p
->inline_buf
;
171 p
->buf_len
= FS_PATH_INLINE_SIZE
;
176 static struct fs_path
*fs_path_alloc_reversed(void)
188 static void fs_path_free(struct fs_path
*p
)
192 if (p
->buf
!= p
->inline_buf
) {
201 static int fs_path_len(struct fs_path
*p
)
203 return p
->end
- p
->start
;
206 static int fs_path_ensure_buf(struct fs_path
*p
, int len
)
214 if (p
->buf_len
>= len
)
217 path_len
= p
->end
- p
->start
;
218 old_buf_len
= p
->buf_len
;
219 len
= PAGE_ALIGN(len
);
221 if (p
->buf
== p
->inline_buf
) {
222 tmp_buf
= kmalloc(len
, GFP_NOFS
| __GFP_NOWARN
);
224 tmp_buf
= vmalloc(len
);
229 memcpy(tmp_buf
, p
->buf
, p
->buf_len
);
233 if (p
->virtual_mem
) {
234 tmp_buf
= vmalloc(len
);
237 memcpy(tmp_buf
, p
->buf
, p
->buf_len
);
240 tmp_buf
= krealloc(p
->buf
, len
, GFP_NOFS
);
242 tmp_buf
= vmalloc(len
);
245 memcpy(tmp_buf
, p
->buf
, p
->buf_len
);
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);
260 p
->end
= p
->start
+ path_len
;
265 static int fs_path_prepare_for_add(struct fs_path
*p
, int name_len
)
270 new_len
= p
->end
- p
->start
+ name_len
;
271 if (p
->start
!= p
->end
)
273 ret
= fs_path_ensure_buf(p
, new_len
);
278 if (p
->start
!= p
->end
)
280 p
->start
-= name_len
;
281 p
->prepared
= p
->start
;
283 if (p
->start
!= p
->end
)
285 p
->prepared
= p
->end
;
294 static int fs_path_add(struct fs_path
*p
, const char *name
, int name_len
)
298 ret
= fs_path_prepare_for_add(p
, name_len
);
301 memcpy(p
->prepared
, name
, name_len
);
308 static int fs_path_add_path(struct fs_path
*p
, struct fs_path
*p2
)
312 ret
= fs_path_prepare_for_add(p
, p2
->end
- p2
->start
);
315 memcpy(p
->prepared
, p2
->start
, p2
->end
- p2
->start
);
322 static int fs_path_add_from_extent_buffer(struct fs_path
*p
,
323 struct extent_buffer
*eb
,
324 unsigned long off
, int len
)
328 ret
= fs_path_prepare_for_add(p
, len
);
332 read_extent_buffer(eb
, p
->prepared
, off
, len
);
340 static void fs_path_remove(struct fs_path
*p
)
343 while (p
->start
!= p
->end
&& *p
->end
!= '/')
349 static int fs_path_copy(struct fs_path
*p
, struct fs_path
*from
)
353 p
->reversed
= from
->reversed
;
356 ret
= fs_path_add_path(p
, from
);
362 static void fs_path_unreverse(struct fs_path
*p
)
371 len
= p
->end
- p
->start
;
373 p
->end
= p
->start
+ len
;
374 memmove(p
->start
, tmp
, len
+ 1);
378 static struct btrfs_path
*alloc_path_for_send(void)
380 struct btrfs_path
*path
;
382 path
= btrfs_alloc_path();
385 path
->search_commit_root
= 1;
386 path
->skip_locking
= 1;
390 static int write_buf(struct file
*filp
, const void *buf
, u32 len
, loff_t
*off
)
400 ret
= vfs_write(filp
, (char *)buf
+ pos
, len
- pos
, off
);
401 /* TODO handle that correctly */
402 /*if (ret == -ERESTARTSYS) {
421 static int tlv_put(struct send_ctx
*sctx
, u16 attr
, const void *data
, int len
)
423 struct btrfs_tlv_header
*hdr
;
424 int total_len
= sizeof(*hdr
) + len
;
425 int left
= sctx
->send_max_size
- sctx
->send_size
;
427 if (unlikely(left
< total_len
))
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
;
440 static int tlv_put_u8(struct send_ctx
*sctx
, u16 attr
, u8 value
)
442 return tlv_put(sctx
, attr
, &value
, sizeof(value
));
445 static int tlv_put_u16(struct send_ctx
*sctx
, u16 attr
, u16 value
)
447 __le16 tmp
= cpu_to_le16(value
);
448 return tlv_put(sctx
, attr
, &tmp
, sizeof(tmp
));
451 static int tlv_put_u32(struct send_ctx
*sctx
, u16 attr
, u32 value
)
453 __le32 tmp
= cpu_to_le32(value
);
454 return tlv_put(sctx
, attr
, &tmp
, sizeof(tmp
));
458 static int tlv_put_u64(struct send_ctx
*sctx
, u16 attr
, u64 value
)
460 __le64 tmp
= cpu_to_le64(value
);
461 return tlv_put(sctx
, attr
, &tmp
, sizeof(tmp
));
464 static int tlv_put_string(struct send_ctx
*sctx
, u16 attr
,
465 const char *str
, int len
)
469 return tlv_put(sctx
, attr
, str
, len
);
472 static int tlv_put_uuid(struct send_ctx
*sctx
, u16 attr
,
475 return tlv_put(sctx
, attr
, uuid
, BTRFS_UUID_SIZE
);
479 static int tlv_put_timespec(struct send_ctx
*sctx
, u16 attr
,
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
));
489 static int tlv_put_btrfs_timespec(struct send_ctx
*sctx
, u16 attr
,
490 struct extent_buffer
*eb
,
491 struct btrfs_timespec
*ts
)
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
));
499 #define TLV_PUT(sctx, attrtype, attrlen, data) \
501 ret = tlv_put(sctx, attrtype, attrlen, data); \
503 goto tlv_put_failure; \
506 #define TLV_PUT_INT(sctx, attrtype, bits, value) \
508 ret = tlv_put_u##bits(sctx, attrtype, value); \
510 goto tlv_put_failure; \
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) \
519 ret = tlv_put_string(sctx, attrtype, str, len); \
521 goto tlv_put_failure; \
523 #define TLV_PUT_PATH(sctx, attrtype, p) \
525 ret = tlv_put_string(sctx, attrtype, p->start, \
526 p->end - p->start); \
528 goto tlv_put_failure; \
530 #define TLV_PUT_UUID(sctx, attrtype, uuid) \
532 ret = tlv_put_uuid(sctx, attrtype, uuid); \
534 goto tlv_put_failure; \
536 #define TLV_PUT_TIMESPEC(sctx, attrtype, ts) \
538 ret = tlv_put_timespec(sctx, attrtype, ts); \
540 goto tlv_put_failure; \
542 #define TLV_PUT_BTRFS_TIMESPEC(sctx, attrtype, eb, ts) \
544 ret = tlv_put_btrfs_timespec(sctx, attrtype, eb, ts); \
546 goto tlv_put_failure; \
549 static int send_header(struct send_ctx
*sctx
)
551 struct btrfs_stream_header hdr
;
553 strcpy(hdr
.magic
, BTRFS_SEND_STREAM_MAGIC
);
554 hdr
.version
= cpu_to_le32(BTRFS_SEND_STREAM_VERSION
);
556 return write_buf(sctx
->send_filp
, &hdr
, sizeof(hdr
),
561 * For each command/item we want to send to userspace, we call this function.
563 static int begin_cmd(struct send_ctx
*sctx
, int cmd
)
565 struct btrfs_cmd_header
*hdr
;
567 if (WARN_ON(!sctx
->send_buf
))
570 BUG_ON(sctx
->send_size
);
572 sctx
->send_size
+= sizeof(*hdr
);
573 hdr
= (struct btrfs_cmd_header
*)sctx
->send_buf
;
574 hdr
->cmd
= cpu_to_le16(cmd
);
579 static int send_cmd(struct send_ctx
*sctx
)
582 struct btrfs_cmd_header
*hdr
;
585 hdr
= (struct btrfs_cmd_header
*)sctx
->send_buf
;
586 hdr
->len
= cpu_to_le32(sctx
->send_size
- sizeof(*hdr
));
589 crc
= crc32c(0, (unsigned char *)sctx
->send_buf
, sctx
->send_size
);
590 hdr
->crc
= cpu_to_le32(crc
);
592 ret
= write_buf(sctx
->send_filp
, sctx
->send_buf
, sctx
->send_size
,
595 sctx
->total_send_size
+= sctx
->send_size
;
596 sctx
->cmd_send_size
[le16_to_cpu(hdr
->cmd
)] += sctx
->send_size
;
603 * Sends a move instruction to user space
605 static int send_rename(struct send_ctx
*sctx
,
606 struct fs_path
*from
, struct fs_path
*to
)
610 verbose_printk("btrfs: send_rename %s -> %s\n", from
->start
, to
->start
);
612 ret
= begin_cmd(sctx
, BTRFS_SEND_C_RENAME
);
616 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, from
);
617 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH_TO
, to
);
619 ret
= send_cmd(sctx
);
627 * Sends a link instruction to user space
629 static int send_link(struct send_ctx
*sctx
,
630 struct fs_path
*path
, struct fs_path
*lnk
)
634 verbose_printk("btrfs: send_link %s -> %s\n", path
->start
, lnk
->start
);
636 ret
= begin_cmd(sctx
, BTRFS_SEND_C_LINK
);
640 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, path
);
641 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH_LINK
, lnk
);
643 ret
= send_cmd(sctx
);
651 * Sends an unlink instruction to user space
653 static int send_unlink(struct send_ctx
*sctx
, struct fs_path
*path
)
657 verbose_printk("btrfs: send_unlink %s\n", path
->start
);
659 ret
= begin_cmd(sctx
, BTRFS_SEND_C_UNLINK
);
663 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, path
);
665 ret
= send_cmd(sctx
);
673 * Sends a rmdir instruction to user space
675 static int send_rmdir(struct send_ctx
*sctx
, struct fs_path
*path
)
679 verbose_printk("btrfs: send_rmdir %s\n", path
->start
);
681 ret
= begin_cmd(sctx
, BTRFS_SEND_C_RMDIR
);
685 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, path
);
687 ret
= send_cmd(sctx
);
695 * Helper function to retrieve some fields from an inode item.
697 static int get_inode_info(struct btrfs_root
*root
,
698 u64 ino
, u64
*size
, u64
*gen
,
699 u64
*mode
, u64
*uid
, u64
*gid
,
703 struct btrfs_inode_item
*ii
;
704 struct btrfs_key key
;
705 struct btrfs_path
*path
;
707 path
= alloc_path_for_send();
712 key
.type
= BTRFS_INODE_ITEM_KEY
;
714 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
722 ii
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
723 struct btrfs_inode_item
);
725 *size
= btrfs_inode_size(path
->nodes
[0], ii
);
727 *gen
= btrfs_inode_generation(path
->nodes
[0], ii
);
729 *mode
= btrfs_inode_mode(path
->nodes
[0], ii
);
731 *uid
= btrfs_inode_uid(path
->nodes
[0], ii
);
733 *gid
= btrfs_inode_gid(path
->nodes
[0], ii
);
735 *rdev
= btrfs_inode_rdev(path
->nodes
[0], ii
);
738 btrfs_free_path(path
);
742 typedef int (*iterate_inode_ref_t
)(int num
, u64 dir
, int index
,
747 * Helper function to iterate the entries in ONE btrfs_inode_ref or
748 * btrfs_inode_extref.
749 * 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.
752 * path must point to the INODE_REF or INODE_EXTREF when called.
754 static int iterate_inode_ref(struct btrfs_root
*root
, struct btrfs_path
*path
,
755 struct btrfs_key
*found_key
, int resolve
,
756 iterate_inode_ref_t iterate
, void *ctx
)
758 struct extent_buffer
*eb
= path
->nodes
[0];
759 struct btrfs_item
*item
;
760 struct btrfs_inode_ref
*iref
;
761 struct btrfs_inode_extref
*extref
;
762 struct btrfs_path
*tmp_path
;
766 int slot
= path
->slots
[0];
773 unsigned long name_off
;
774 unsigned long elem_size
;
777 p
= fs_path_alloc_reversed();
781 tmp_path
= alloc_path_for_send();
788 if (found_key
->type
== BTRFS_INODE_REF_KEY
) {
789 ptr
= (unsigned long)btrfs_item_ptr(eb
, slot
,
790 struct btrfs_inode_ref
);
791 item
= btrfs_item_nr(slot
);
792 total
= btrfs_item_size(eb
, item
);
793 elem_size
= sizeof(*iref
);
795 ptr
= btrfs_item_ptr_offset(eb
, slot
);
796 total
= btrfs_item_size_nr(eb
, slot
);
797 elem_size
= sizeof(*extref
);
800 while (cur
< total
) {
803 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
;
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
);
818 start
= btrfs_ref_to_path(root
, tmp_path
, name_len
,
822 ret
= PTR_ERR(start
);
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
);
831 start
= btrfs_ref_to_path(root
, tmp_path
,
836 ret
= PTR_ERR(start
);
839 BUG_ON(start
< p
->buf
);
843 ret
= fs_path_add_from_extent_buffer(p
, eb
, name_off
,
849 cur
+= elem_size
+ name_len
;
850 ret
= iterate(num
, dir
, index
, p
, ctx
);
857 btrfs_free_path(tmp_path
);
862 typedef 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
,
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.
872 * path must point to the dir item when called.
874 static int iterate_dir_item(struct btrfs_root
*root
, struct btrfs_path
*path
,
875 struct btrfs_key
*found_key
,
876 iterate_dir_item_t iterate
, void *ctx
)
879 struct extent_buffer
*eb
;
880 struct btrfs_item
*item
;
881 struct btrfs_dir_item
*di
;
882 struct btrfs_key di_key
;
897 buf
= kmalloc(buf_len
, GFP_NOFS
);
904 slot
= path
->slots
[0];
905 item
= btrfs_item_nr(slot
);
906 di
= btrfs_item_ptr(eb
, slot
, struct btrfs_dir_item
);
909 total
= btrfs_item_size(eb
, item
);
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
);
918 if (name_len
+ data_len
> buf_len
) {
919 buf_len
= PAGE_ALIGN(name_len
+ data_len
);
921 buf2
= vmalloc(buf_len
);
928 buf2
= krealloc(buf
, buf_len
, GFP_NOFS
);
930 buf2
= vmalloc(buf_len
);
944 read_extent_buffer(eb
, buf
, (unsigned long)(di
+ 1),
945 name_len
+ data_len
);
947 len
= sizeof(*di
) + name_len
+ data_len
;
948 di
= (struct btrfs_dir_item
*)((char *)di
+ len
);
951 ret
= iterate(num
, &di_key
, buf
, name_len
, buf
+ name_len
,
952 data_len
, type
, ctx
);
971 static int __copy_first_ref(int num
, u64 dir
, int index
,
972 struct fs_path
*p
, void *ctx
)
975 struct fs_path
*pt
= ctx
;
977 ret
= fs_path_copy(pt
, p
);
981 /* we want the first only */
986 * Retrieve the first path of an inode. If an inode has more then one
987 * ref/hardlink, this is ignored.
989 static int get_inode_path(struct btrfs_root
*root
,
990 u64 ino
, struct fs_path
*path
)
993 struct btrfs_key key
, found_key
;
994 struct btrfs_path
*p
;
996 p
= alloc_path_for_send();
1000 fs_path_reset(path
);
1003 key
.type
= BTRFS_INODE_REF_KEY
;
1006 ret
= btrfs_search_slot_for_read(root
, &key
, p
, 1, 0);
1013 btrfs_item_key_to_cpu(p
->nodes
[0], &found_key
, p
->slots
[0]);
1014 if (found_key
.objectid
!= ino
||
1015 (found_key
.type
!= BTRFS_INODE_REF_KEY
&&
1016 found_key
.type
!= BTRFS_INODE_EXTREF_KEY
)) {
1021 ret
= iterate_inode_ref(root
, p
, &found_key
, 1,
1022 __copy_first_ref
, path
);
1032 struct backref_ctx
{
1033 struct send_ctx
*sctx
;
1035 /* number of total found references */
1039 * used for clones found in send_root. clones found behind cur_objectid
1040 * and cur_offset are not considered as allowed clones.
1045 /* may be truncated in case it's the last extent in a file */
1048 /* Just to check for bugs in backref resolving */
1052 static int __clone_root_cmp_bsearch(const void *key
, const void *elt
)
1054 u64 root
= (u64
)(uintptr_t)key
;
1055 struct clone_root
*cr
= (struct clone_root
*)elt
;
1057 if (root
< cr
->root
->objectid
)
1059 if (root
> cr
->root
->objectid
)
1064 static int __clone_root_cmp_sort(const void *e1
, const void *e2
)
1066 struct clone_root
*cr1
= (struct clone_root
*)e1
;
1067 struct clone_root
*cr2
= (struct clone_root
*)e2
;
1069 if (cr1
->root
->objectid
< cr2
->root
->objectid
)
1071 if (cr1
->root
->objectid
> cr2
->root
->objectid
)
1077 * Called for every backref that is found for the current extent.
1078 * Results are collected in sctx->clone_roots->ino/offset/found_refs
1080 static int __iterate_backrefs(u64 ino
, u64 offset
, u64 root
, void *ctx_
)
1082 struct backref_ctx
*bctx
= ctx_
;
1083 struct clone_root
*found
;
1087 /* First check if the root is in the list of accepted clone sources */
1088 found
= bsearch((void *)(uintptr_t)root
, bctx
->sctx
->clone_roots
,
1089 bctx
->sctx
->clone_roots_cnt
,
1090 sizeof(struct clone_root
),
1091 __clone_root_cmp_bsearch
);
1095 if (found
->root
== bctx
->sctx
->send_root
&&
1096 ino
== bctx
->cur_objectid
&&
1097 offset
== bctx
->cur_offset
) {
1098 bctx
->found_itself
= 1;
1102 * There are inodes that have extents that lie behind its i_size. Don't
1103 * accept clones from these extents.
1105 ret
= get_inode_info(found
->root
, ino
, &i_size
, NULL
, NULL
, NULL
, NULL
,
1110 if (offset
+ bctx
->extent_len
> i_size
)
1114 * Make sure we don't consider clones from send_root that are
1115 * behind the current inode/offset.
1117 if (found
->root
== bctx
->sctx
->send_root
) {
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
1124 if (ino
>= bctx
->cur_objectid
)
1127 if (ino
> bctx
->cur_objectid
)
1129 if (offset
+ bctx
->extent_len
> bctx
->cur_offset
)
1135 found
->found_refs
++;
1136 if (ino
< found
->ino
) {
1138 found
->offset
= offset
;
1139 } else if (found
->ino
== ino
) {
1141 * same extent found more then once in the same file.
1143 if (found
->offset
> offset
+ bctx
->extent_len
)
1144 found
->offset
= offset
;
1151 * 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
1157 * path must point to the extent item when called.
1159 static int find_extent_clone(struct send_ctx
*sctx
,
1160 struct btrfs_path
*path
,
1161 u64 ino
, u64 data_offset
,
1163 struct clone_root
**found
)
1170 u64 extent_item_pos
;
1172 struct btrfs_file_extent_item
*fi
;
1173 struct extent_buffer
*eb
= path
->nodes
[0];
1174 struct backref_ctx
*backref_ctx
= NULL
;
1175 struct clone_root
*cur_clone_root
;
1176 struct btrfs_key found_key
;
1177 struct btrfs_path
*tmp_path
;
1181 tmp_path
= alloc_path_for_send();
1185 backref_ctx
= kmalloc(sizeof(*backref_ctx
), GFP_NOFS
);
1191 if (data_offset
>= ino_size
) {
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.
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
) {
1208 compressed
= btrfs_file_extent_compression(eb
, fi
);
1210 num_bytes
= btrfs_file_extent_num_bytes(eb
, fi
);
1211 disk_byte
= btrfs_file_extent_disk_bytenr(eb
, fi
);
1212 if (disk_byte
== 0) {
1216 logical
= disk_byte
+ btrfs_file_extent_offset(eb
, fi
);
1218 ret
= extent_from_logical(sctx
->send_root
->fs_info
, disk_byte
, tmp_path
,
1219 &found_key
, &flags
);
1220 btrfs_release_path(tmp_path
);
1224 if (flags
& BTRFS_EXTENT_FLAG_TREE_BLOCK
) {
1230 * Setup the clone roots.
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;
1239 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
;
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.
1251 if (data_offset
+ num_bytes
>= ino_size
)
1252 backref_ctx
->extent_len
= ino_size
- data_offset
;
1255 * Now collect all backrefs.
1257 if (compressed
== BTRFS_COMPRESS_NONE
)
1258 extent_item_pos
= logical
- found_key
.objectid
;
1260 extent_item_pos
= 0;
1262 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,
1265 __iterate_backrefs
, backref_ctx
);
1270 if (!backref_ctx
->found_itself
) {
1271 /* found a bug in backref code? */
1273 printk(KERN_ERR
"btrfs: ERROR did not find backref in "
1274 "send_root. inode=%llu, offset=%llu, "
1275 "disk_byte=%llu found extent=%llu\n",
1276 ino
, data_offset
, disk_byte
, found_key
.objectid
);
1280 verbose_printk(KERN_DEBUG
"btrfs: find_extent_clone: data_offset=%llu, "
1282 "num_bytes=%llu, logical=%llu\n",
1283 data_offset
, ino
, num_bytes
, logical
);
1285 if (!backref_ctx
->found
)
1286 verbose_printk("btrfs: no clones found\n");
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
;
1300 if (cur_clone_root
) {
1301 *found
= cur_clone_root
;
1308 btrfs_free_path(tmp_path
);
1313 static int read_symlink(struct btrfs_root
*root
,
1315 struct fs_path
*dest
)
1318 struct btrfs_path
*path
;
1319 struct btrfs_key key
;
1320 struct btrfs_file_extent_item
*ei
;
1326 path
= alloc_path_for_send();
1331 key
.type
= BTRFS_EXTENT_DATA_KEY
;
1333 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
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
);
1345 off
= btrfs_file_extent_inline_start(ei
);
1346 len
= btrfs_file_extent_inline_len(path
->nodes
[0], ei
);
1348 ret
= fs_path_add_from_extent_buffer(dest
, path
->nodes
[0], off
, len
);
1351 btrfs_free_path(path
);
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.
1359 static int gen_unique_name(struct send_ctx
*sctx
,
1361 struct fs_path
*dest
)
1364 struct btrfs_path
*path
;
1365 struct btrfs_dir_item
*di
;
1370 path
= alloc_path_for_send();
1375 len
= snprintf(tmp
, sizeof(tmp
) - 1, "o%llu-%llu-%llu",
1377 if (len
>= sizeof(tmp
)) {
1378 /* should really not happen */
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
);
1392 /* not unique, try again */
1397 if (!sctx
->parent_root
) {
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
);
1412 /* not unique, try again */
1420 ret
= fs_path_add(dest
, tmp
, strlen(tmp
));
1423 btrfs_free_path(path
);
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
,
1435 static int get_cur_inode_state(struct send_ctx
*sctx
, u64 ino
, u64 gen
)
1443 ret
= get_inode_info(sctx
->send_root
, ino
, NULL
, &left_gen
, NULL
, NULL
,
1445 if (ret
< 0 && ret
!= -ENOENT
)
1449 if (!sctx
->parent_root
) {
1450 right_ret
= -ENOENT
;
1452 ret
= get_inode_info(sctx
->parent_root
, ino
, NULL
, &right_gen
,
1453 NULL
, NULL
, NULL
, NULL
);
1454 if (ret
< 0 && ret
!= -ENOENT
)
1459 if (!left_ret
&& !right_ret
) {
1460 if (left_gen
== gen
&& right_gen
== gen
) {
1461 ret
= inode_state_no_change
;
1462 } else if (left_gen
== gen
) {
1463 if (ino
< sctx
->send_progress
)
1464 ret
= inode_state_did_create
;
1466 ret
= inode_state_will_create
;
1467 } else if (right_gen
== gen
) {
1468 if (ino
< sctx
->send_progress
)
1469 ret
= inode_state_did_delete
;
1471 ret
= inode_state_will_delete
;
1475 } else if (!left_ret
) {
1476 if (left_gen
== gen
) {
1477 if (ino
< sctx
->send_progress
)
1478 ret
= inode_state_did_create
;
1480 ret
= inode_state_will_create
;
1484 } else if (!right_ret
) {
1485 if (right_gen
== gen
) {
1486 if (ino
< sctx
->send_progress
)
1487 ret
= inode_state_did_delete
;
1489 ret
= inode_state_will_delete
;
1501 static int is_inode_existent(struct send_ctx
*sctx
, u64 ino
, u64 gen
)
1505 ret
= get_cur_inode_state(sctx
, ino
, gen
);
1509 if (ret
== inode_state_no_change
||
1510 ret
== inode_state_did_create
||
1511 ret
== inode_state_will_delete
)
1521 * Helper function to lookup a dir item in a dir.
1523 static int lookup_dir_item_inode(struct btrfs_root
*root
,
1524 u64 dir
, const char *name
, int name_len
,
1529 struct btrfs_dir_item
*di
;
1530 struct btrfs_key key
;
1531 struct btrfs_path
*path
;
1533 path
= alloc_path_for_send();
1537 di
= btrfs_lookup_dir_item(NULL
, root
, path
,
1538 dir
, name
, name_len
, 0);
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
);
1552 btrfs_free_path(path
);
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.
1560 static int get_first_ref(struct btrfs_root
*root
, u64 ino
,
1561 u64
*dir
, u64
*dir_gen
, struct fs_path
*name
)
1564 struct btrfs_key key
;
1565 struct btrfs_key found_key
;
1566 struct btrfs_path
*path
;
1570 path
= alloc_path_for_send();
1575 key
.type
= BTRFS_INODE_REF_KEY
;
1578 ret
= btrfs_search_slot_for_read(root
, &key
, path
, 1, 0);
1582 btrfs_item_key_to_cpu(path
->nodes
[0], &found_key
,
1584 if (ret
|| found_key
.objectid
!= ino
||
1585 (found_key
.type
!= BTRFS_INODE_REF_KEY
&&
1586 found_key
.type
!= BTRFS_INODE_EXTREF_KEY
)) {
1591 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),
1599 parent_dir
= found_key
.offset
;
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
);
1611 btrfs_release_path(path
);
1613 ret
= get_inode_info(root
, parent_dir
, NULL
, dir_gen
, NULL
, NULL
,
1621 btrfs_free_path(path
);
1625 static int is_first_ref(struct btrfs_root
*root
,
1627 const char *name
, int name_len
)
1630 struct fs_path
*tmp_name
;
1634 tmp_name
= fs_path_alloc();
1638 ret
= get_first_ref(root
, ino
, &tmp_dir
, &tmp_dir_gen
, tmp_name
);
1642 if (dir
!= tmp_dir
|| name_len
!= fs_path_len(tmp_name
)) {
1647 ret
= !memcmp(tmp_name
->start
, name
, name_len
);
1650 fs_path_free(tmp_name
);
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.
1664 static 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
)
1670 u64 other_inode
= 0;
1673 if (!sctx
->parent_root
)
1676 ret
= is_inode_existent(sctx
, dir
, dir_gen
);
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.
1685 if (sctx
->parent_root
) {
1686 ret
= get_inode_info(sctx
->parent_root
, dir
, NULL
, &gen
, NULL
,
1688 if (ret
< 0 && ret
!= -ENOENT
)
1698 ret
= lookup_dir_item_inode(sctx
->parent_root
, dir
, name
, name_len
,
1699 &other_inode
, &other_type
);
1700 if (ret
< 0 && ret
!= -ENOENT
)
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.
1712 if (other_inode
> sctx
->send_progress
) {
1713 ret
= get_inode_info(sctx
->parent_root
, other_inode
, NULL
,
1714 who_gen
, NULL
, NULL
, NULL
, NULL
);
1719 *who_ino
= other_inode
;
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
1735 static 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
)
1745 if (!sctx
->parent_root
)
1748 ret
= is_inode_existent(sctx
, dir
, dir_gen
);
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
)
1758 /* was never and will never be overwritten */
1763 ret
= get_inode_info(sctx
->send_root
, ow_inode
, NULL
, &gen
, NULL
, NULL
,
1768 if (ow_inode
== ino
&& gen
== ino_gen
) {
1773 /* we know that it is or will be overwritten. check this now */
1774 if (ow_inode
< sctx
->send_progress
)
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.
1788 static int did_overwrite_first_ref(struct send_ctx
*sctx
, u64 ino
, u64 gen
)
1791 struct fs_path
*name
= NULL
;
1795 if (!sctx
->parent_root
)
1798 name
= fs_path_alloc();
1802 ret
= get_first_ref(sctx
->parent_root
, ino
, &dir
, &dir_gen
, name
);
1806 ret
= did_overwrite_ref(sctx
, dir
, dir_gen
, ino
, gen
,
1807 name
->start
, fs_path_len(name
));
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.
1818 * In case of error, nce is kfreed.
1820 static int name_cache_insert(struct send_ctx
*sctx
,
1821 struct name_cache_entry
*nce
)
1824 struct list_head
*nce_head
;
1826 nce_head
= radix_tree_lookup(&sctx
->name_cache
,
1827 (unsigned long)nce
->ino
);
1829 nce_head
= kmalloc(sizeof(*nce_head
), GFP_NOFS
);
1834 INIT_LIST_HEAD(nce_head
);
1836 ret
= radix_tree_insert(&sctx
->name_cache
, nce
->ino
, nce_head
);
1843 list_add_tail(&nce
->radix_list
, nce_head
);
1844 list_add_tail(&nce
->list
, &sctx
->name_cache_list
);
1845 sctx
->name_cache_size
++;
1850 static void name_cache_delete(struct send_ctx
*sctx
,
1851 struct name_cache_entry
*nce
)
1853 struct list_head
*nce_head
;
1855 nce_head
= radix_tree_lookup(&sctx
->name_cache
,
1856 (unsigned long)nce
->ino
);
1859 list_del(&nce
->radix_list
);
1860 list_del(&nce
->list
);
1861 sctx
->name_cache_size
--;
1863 if (list_empty(nce_head
)) {
1864 radix_tree_delete(&sctx
->name_cache
, (unsigned long)nce
->ino
);
1869 static struct name_cache_entry
*name_cache_search(struct send_ctx
*sctx
,
1872 struct list_head
*nce_head
;
1873 struct name_cache_entry
*cur
;
1875 nce_head
= radix_tree_lookup(&sctx
->name_cache
, (unsigned long)ino
);
1879 list_for_each_entry(cur
, nce_head
, radix_list
) {
1880 if (cur
->ino
== ino
&& cur
->gen
== gen
)
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.
1890 static void name_cache_used(struct send_ctx
*sctx
, struct name_cache_entry
*nce
)
1892 list_del(&nce
->list
);
1893 list_add_tail(&nce
->list
, &sctx
->name_cache_list
);
1897 * Remove some entries from the beginning of name_cache_list.
1899 static void name_cache_clean_unused(struct send_ctx
*sctx
)
1901 struct name_cache_entry
*nce
;
1903 if (sctx
->name_cache_size
< SEND_CTX_NAME_CACHE_CLEAN_SIZE
)
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
);
1914 static void name_cache_free(struct send_ctx
*sctx
)
1916 struct name_cache_entry
*nce
;
1918 while (!list_empty(&sctx
->name_cache_list
)) {
1919 nce
= list_entry(sctx
->name_cache_list
.next
,
1920 struct name_cache_entry
, list
);
1921 name_cache_delete(sctx
, nce
);
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.
1934 static int __get_cur_name_and_parent(struct send_ctx
*sctx
,
1938 struct fs_path
*dest
)
1942 struct btrfs_path
*path
= NULL
;
1943 struct name_cache_entry
*nce
= NULL
;
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.
1950 nce
= name_cache_search(sctx
, ino
, gen
);
1952 if (ino
< sctx
->send_progress
&& nce
->need_later_update
) {
1953 name_cache_delete(sctx
, nce
);
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
);
1968 path
= alloc_path_for_send();
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
1977 ret
= is_inode_existent(sctx
, ino
, gen
);
1982 ret
= gen_unique_name(sctx
, ino
, gen
, dest
);
1990 * Depending on whether the inode was already processed or not, use
1991 * send_root or parent_root for ref lookup.
1993 if (ino
< sctx
->send_progress
)
1994 ret
= get_first_ref(sctx
->send_root
, ino
,
1995 parent_ino
, parent_gen
, dest
);
1997 ret
= get_first_ref(sctx
->parent_root
, ino
,
1998 parent_ino
, parent_gen
, dest
);
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.
2006 ret
= did_overwrite_ref(sctx
, *parent_ino
, *parent_gen
, ino
, gen
,
2007 dest
->start
, dest
->end
- dest
->start
);
2011 fs_path_reset(dest
);
2012 ret
= gen_unique_name(sctx
, ino
, gen
, dest
);
2020 * Store the result of the lookup in the name cache.
2022 nce
= kmalloc(sizeof(*nce
) + fs_path_len(dest
) + 1, GFP_NOFS
);
2030 nce
->parent_ino
= *parent_ino
;
2031 nce
->parent_gen
= *parent_gen
;
2032 nce
->name_len
= fs_path_len(dest
);
2034 strcpy(nce
->name
, dest
->start
);
2036 if (ino
< sctx
->send_progress
)
2037 nce
->need_later_update
= 0;
2039 nce
->need_later_update
= 1;
2041 nce_ret
= name_cache_insert(sctx
, nce
);
2044 name_cache_clean_unused(sctx
);
2047 btrfs_free_path(path
);
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.
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
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
2073 * sctx->send_progress tells this function at which point in time receiving
2076 static int get_cur_path(struct send_ctx
*sctx
, u64 ino
, u64 gen
,
2077 struct fs_path
*dest
)
2080 struct fs_path
*name
= NULL
;
2081 u64 parent_inode
= 0;
2085 name
= fs_path_alloc();
2092 fs_path_reset(dest
);
2094 while (!stop
&& ino
!= BTRFS_FIRST_FREE_OBJECTID
) {
2095 fs_path_reset(name
);
2097 ret
= __get_cur_name_and_parent(sctx
, ino
, gen
,
2098 &parent_inode
, &parent_gen
, name
);
2104 ret
= fs_path_add_path(dest
, name
);
2115 fs_path_unreverse(dest
);
2120 * Sends a BTRFS_SEND_C_SUBVOL command/item to userspace
2122 static int send_subvol_begin(struct send_ctx
*sctx
)
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
;
2134 path
= alloc_path_for_send();
2138 name
= kmalloc(BTRFS_PATH_NAME_MAX
, GFP_NOFS
);
2140 btrfs_free_path(path
);
2144 key
.objectid
= send_root
->objectid
;
2145 key
.type
= BTRFS_ROOT_BACKREF_KEY
;
2148 ret
= btrfs_search_slot_for_read(send_root
->fs_info
->tree_root
,
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
) {
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
);
2170 ret
= begin_cmd(sctx
, BTRFS_SEND_C_SNAPSHOT
);
2174 ret
= begin_cmd(sctx
, BTRFS_SEND_C_SUBVOL
);
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
);
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
);
2191 ret
= send_cmd(sctx
);
2195 btrfs_free_path(path
);
2200 static int send_truncate(struct send_ctx
*sctx
, u64 ino
, u64 gen
, u64 size
)
2205 verbose_printk("btrfs: send_truncate %llu size=%llu\n", ino
, size
);
2207 p
= fs_path_alloc();
2211 ret
= begin_cmd(sctx
, BTRFS_SEND_C_TRUNCATE
);
2215 ret
= get_cur_path(sctx
, ino
, gen
, p
);
2218 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, p
);
2219 TLV_PUT_U64(sctx
, BTRFS_SEND_A_SIZE
, size
);
2221 ret
= send_cmd(sctx
);
2229 static int send_chmod(struct send_ctx
*sctx
, u64 ino
, u64 gen
, u64 mode
)
2234 verbose_printk("btrfs: send_chmod %llu mode=%llu\n", ino
, mode
);
2236 p
= fs_path_alloc();
2240 ret
= begin_cmd(sctx
, BTRFS_SEND_C_CHMOD
);
2244 ret
= get_cur_path(sctx
, ino
, gen
, p
);
2247 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, p
);
2248 TLV_PUT_U64(sctx
, BTRFS_SEND_A_MODE
, mode
& 07777);
2250 ret
= send_cmd(sctx
);
2258 static int send_chown(struct send_ctx
*sctx
, u64 ino
, u64 gen
, u64 uid
, u64 gid
)
2263 verbose_printk("btrfs: send_chown %llu uid=%llu, gid=%llu\n", ino
, uid
, gid
);
2265 p
= fs_path_alloc();
2269 ret
= begin_cmd(sctx
, BTRFS_SEND_C_CHOWN
);
2273 ret
= get_cur_path(sctx
, ino
, gen
, p
);
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
);
2280 ret
= send_cmd(sctx
);
2288 static int send_utimes(struct send_ctx
*sctx
, u64 ino
, u64 gen
)
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
;
2298 verbose_printk("btrfs: send_utimes %llu\n", ino
);
2300 p
= fs_path_alloc();
2304 path
= alloc_path_for_send();
2311 key
.type
= BTRFS_INODE_ITEM_KEY
;
2313 ret
= btrfs_search_slot(NULL
, sctx
->send_root
, &key
, path
, 0, 0);
2317 eb
= path
->nodes
[0];
2318 slot
= path
->slots
[0];
2319 ii
= btrfs_item_ptr(eb
, slot
, struct btrfs_inode_item
);
2321 ret
= begin_cmd(sctx
, BTRFS_SEND_C_UTIMES
);
2325 ret
= get_cur_path(sctx
, ino
, gen
, p
);
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
));
2335 /* TODO Add otime support when the otime patches get into upstream */
2337 ret
= send_cmd(sctx
);
2342 btrfs_free_path(path
);
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.
2351 static int send_create_inode(struct send_ctx
*sctx
, u64 ino
)
2360 verbose_printk("btrfs: send_create_inode %llu\n", ino
);
2362 p
= fs_path_alloc();
2366 ret
= get_inode_info(sctx
->send_root
, ino
, NULL
, &gen
, &mode
, NULL
,
2371 if (S_ISREG(mode
)) {
2372 cmd
= BTRFS_SEND_C_MKFILE
;
2373 } else if (S_ISDIR(mode
)) {
2374 cmd
= BTRFS_SEND_C_MKDIR
;
2375 } else if (S_ISLNK(mode
)) {
2376 cmd
= BTRFS_SEND_C_SYMLINK
;
2377 } else if (S_ISCHR(mode
) || S_ISBLK(mode
)) {
2378 cmd
= BTRFS_SEND_C_MKNOD
;
2379 } else if (S_ISFIFO(mode
)) {
2380 cmd
= BTRFS_SEND_C_MKFIFO
;
2381 } else if (S_ISSOCK(mode
)) {
2382 cmd
= BTRFS_SEND_C_MKSOCK
;
2384 printk(KERN_WARNING
"btrfs: unexpected inode type %o",
2385 (int)(mode
& S_IFMT
));
2390 ret
= begin_cmd(sctx
, cmd
);
2394 ret
= gen_unique_name(sctx
, ino
, gen
, p
);
2398 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, p
);
2399 TLV_PUT_U64(sctx
, BTRFS_SEND_A_INO
, ino
);
2401 if (S_ISLNK(mode
)) {
2403 ret
= read_symlink(sctx
->send_root
, ino
, p
);
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
)) {
2409 TLV_PUT_U64(sctx
, BTRFS_SEND_A_RDEV
, new_encode_dev(rdev
));
2410 TLV_PUT_U64(sctx
, BTRFS_SEND_A_MODE
, mode
);
2413 ret
= send_cmd(sctx
);
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.
2429 static int did_create_dir(struct send_ctx
*sctx
, u64 dir
)
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
;
2440 path
= alloc_path_for_send();
2447 key
.type
= BTRFS_DIR_INDEX_KEY
;
2450 ret
= btrfs_search_slot_for_read(sctx
->send_root
, &key
, path
,
2455 eb
= path
->nodes
[0];
2456 slot
= path
->slots
[0];
2457 btrfs_item_key_to_cpu(eb
, &found_key
, slot
);
2459 if (ret
|| found_key
.objectid
!= key
.objectid
||
2460 found_key
.type
!= key
.type
) {
2465 di
= btrfs_item_ptr(eb
, slot
, struct btrfs_dir_item
);
2466 btrfs_dir_item_key_to_cpu(eb
, di
, &di_key
);
2468 if (di_key
.type
!= BTRFS_ROOT_ITEM_KEY
&&
2469 di_key
.objectid
< sctx
->send_progress
) {
2474 key
.offset
= found_key
.offset
+ 1;
2475 btrfs_release_path(path
);
2479 btrfs_free_path(path
);
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.
2489 static int send_create_inode_if_needed(struct send_ctx
*sctx
)
2493 if (S_ISDIR(sctx
->cur_inode_mode
)) {
2494 ret
= did_create_dir(sctx
, sctx
->cur_ino
);
2503 ret
= send_create_inode(sctx
, sctx
->cur_ino
);
2511 struct recorded_ref
{
2512 struct list_head list
;
2515 struct fs_path
*full_path
;
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.
2527 static int record_ref(struct list_head
*head
, u64 dir
,
2528 u64 dir_gen
, struct fs_path
*path
)
2530 struct recorded_ref
*ref
;
2532 ref
= kmalloc(sizeof(*ref
), GFP_NOFS
);
2537 ref
->dir_gen
= dir_gen
;
2538 ref
->full_path
= path
;
2540 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
)
2544 ref
->dir_path_len
= 0;
2546 ref
->dir_path_len
= ref
->full_path
->end
-
2547 ref
->full_path
->start
- 1 - ref
->name_len
;
2549 list_add_tail(&ref
->list
, head
);
2553 static int dup_ref(struct recorded_ref
*ref
, struct list_head
*list
)
2555 struct recorded_ref
*new;
2557 new = kmalloc(sizeof(*ref
), GFP_NOFS
);
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
);
2569 static void __free_recorded_refs(struct list_head
*head
)
2571 struct recorded_ref
*cur
;
2573 while (!list_empty(head
)) {
2574 cur
= list_entry(head
->next
, struct recorded_ref
, list
);
2575 fs_path_free(cur
->full_path
);
2576 list_del(&cur
->list
);
2581 static void free_recorded_refs(struct send_ctx
*sctx
)
2583 __free_recorded_refs(&sctx
->new_refs
);
2584 __free_recorded_refs(&sctx
->deleted_refs
);
2588 * Renames/moves a file/dir to its orphan name. Used when the first
2589 * ref of an unprocessed inode gets overwritten and for all non empty
2592 static int orphanize_inode(struct send_ctx
*sctx
, u64 ino
, u64 gen
,
2593 struct fs_path
*path
)
2596 struct fs_path
*orphan
;
2598 orphan
= fs_path_alloc();
2602 ret
= gen_unique_name(sctx
, ino
, gen
, orphan
);
2606 ret
= send_rename(sctx
, path
, orphan
);
2609 fs_path_free(orphan
);
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.
2618 static int can_rmdir(struct send_ctx
*sctx
, u64 dir
, u64 send_progress
)
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
;
2629 * Don't try to rmdir the top/root subvolume dir.
2631 if (dir
== BTRFS_FIRST_FREE_OBJECTID
)
2634 path
= alloc_path_for_send();
2639 key
.type
= BTRFS_DIR_INDEX_KEY
;
2643 ret
= btrfs_search_slot_for_read(root
, &key
, path
, 1, 0);
2647 btrfs_item_key_to_cpu(path
->nodes
[0], &found_key
,
2650 if (ret
|| found_key
.objectid
!= key
.objectid
||
2651 found_key
.type
!= key
.type
) {
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
);
2659 if (loc
.objectid
> send_progress
) {
2664 btrfs_release_path(path
);
2665 key
.offset
= found_key
.offset
+ 1;
2671 btrfs_free_path(path
);
2676 * This does all the move/link/unlink/rmdir magic.
2678 static int process_recorded_refs(struct send_ctx
*sctx
)
2681 struct recorded_ref
*cur
;
2682 struct recorded_ref
*cur2
;
2683 struct list_head check_dirs
;
2684 struct fs_path
*valid_path
= NULL
;
2687 int did_overwrite
= 0;
2690 verbose_printk("btrfs: process_recorded_refs %llu\n", sctx
->cur_ino
);
2693 * This should never happen as the root dir always has the same ref
2694 * which is always '..'
2696 BUG_ON(sctx
->cur_ino
<= BTRFS_FIRST_FREE_OBJECTID
);
2697 INIT_LIST_HEAD(&check_dirs
);
2699 valid_path
= fs_path_alloc();
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.
2716 if (!sctx
->cur_inode_new
) {
2717 ret
= did_overwrite_first_ref(sctx
, sctx
->cur_ino
,
2718 sctx
->cur_inode_gen
);
2724 if (sctx
->cur_inode_new
|| did_overwrite
) {
2725 ret
= gen_unique_name(sctx
, sctx
->cur_ino
,
2726 sctx
->cur_inode_gen
, valid_path
);
2731 ret
= get_cur_path(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
,
2737 list_for_each_entry(cur
, &sctx
->new_refs
, list
) {
2739 * 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.
2745 ret
= get_cur_inode_state(sctx
, cur
->dir
, cur
->dir_gen
);
2748 if (ret
== inode_state_will_create
) {
2751 * First check if any of the current inodes refs did
2752 * already create the dir.
2754 list_for_each_entry(cur2
, &sctx
->new_refs
, list
) {
2757 if (cur2
->dir
== cur
->dir
) {
2764 * If that did not happen, check if a previous inode
2765 * did already create the dir.
2768 ret
= did_create_dir(sctx
, cur
->dir
);
2772 ret
= send_create_inode(sctx
, cur
->dir
);
2779 * 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.
2784 ret
= will_overwrite_ref(sctx
, cur
->dir
, cur
->dir_gen
,
2785 cur
->name
, cur
->name_len
,
2786 &ow_inode
, &ow_gen
);
2790 ret
= is_first_ref(sctx
->parent_root
,
2791 ow_inode
, cur
->dir
, cur
->name
,
2796 ret
= orphanize_inode(sctx
, ow_inode
, ow_gen
,
2801 ret
= send_unlink(sctx
, cur
->full_path
);
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.
2813 ret
= send_rename(sctx
, valid_path
, cur
->full_path
);
2817 ret
= fs_path_copy(valid_path
, cur
->full_path
);
2821 if (S_ISDIR(sctx
->cur_inode_mode
)) {
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.
2827 ret
= send_rename(sctx
, valid_path
,
2831 ret
= fs_path_copy(valid_path
, cur
->full_path
);
2835 ret
= send_link(sctx
, cur
->full_path
,
2841 ret
= dup_ref(cur
, &check_dirs
);
2846 if (S_ISDIR(sctx
->cur_inode_mode
) && sctx
->cur_inode_deleted
) {
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.
2853 ret
= can_rmdir(sctx
, sctx
->cur_ino
, sctx
->cur_ino
);
2857 ret
= send_rmdir(sctx
, valid_path
);
2860 } else if (!is_orphan
) {
2861 ret
= orphanize_inode(sctx
, sctx
->cur_ino
,
2862 sctx
->cur_inode_gen
, valid_path
);
2868 list_for_each_entry(cur
, &sctx
->deleted_refs
, list
) {
2869 ret
= dup_ref(cur
, &check_dirs
);
2873 } else if (S_ISDIR(sctx
->cur_inode_mode
) &&
2874 !list_empty(&sctx
->deleted_refs
)) {
2876 * We have a moved dir. Add the old parent to check_dirs
2878 cur
= list_entry(sctx
->deleted_refs
.next
, struct recorded_ref
,
2880 ret
= dup_ref(cur
, &check_dirs
);
2883 } else if (!S_ISDIR(sctx
->cur_inode_mode
)) {
2885 * We have a non dir inode. Go through all deleted refs and
2886 * unlink them if they were not already overwritten by other
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
);
2896 ret
= send_unlink(sctx
, cur
->full_path
);
2900 ret
= dup_ref(cur
, &check_dirs
);
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
2908 * inode. Unlinking does not mean that the inode is deleted in
2909 * all cases. There may still be links to this inode in other
2913 ret
= send_unlink(sctx
, valid_path
);
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.
2925 list_for_each_entry(cur
, &check_dirs
, list
) {
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.
2931 if (cur
->dir
> sctx
->cur_ino
)
2934 ret
= get_cur_inode_state(sctx
, cur
->dir
, cur
->dir_gen
);
2938 if (ret
== inode_state_did_create
||
2939 ret
== inode_state_no_change
) {
2940 /* TODO delayed utimes */
2941 ret
= send_utimes(sctx
, cur
->dir
, cur
->dir_gen
);
2944 } else if (ret
== inode_state_did_delete
) {
2945 ret
= can_rmdir(sctx
, cur
->dir
, sctx
->cur_ino
);
2949 ret
= get_cur_path(sctx
, cur
->dir
,
2950 cur
->dir_gen
, valid_path
);
2953 ret
= send_rmdir(sctx
, valid_path
);
2963 __free_recorded_refs(&check_dirs
);
2964 free_recorded_refs(sctx
);
2965 fs_path_free(valid_path
);
2969 static int __record_new_ref(int num
, u64 dir
, int index
,
2970 struct fs_path
*name
,
2974 struct send_ctx
*sctx
= ctx
;
2978 p
= fs_path_alloc();
2982 ret
= get_inode_info(sctx
->send_root
, dir
, NULL
, &gen
, NULL
, NULL
,
2987 ret
= get_cur_path(sctx
, dir
, gen
, p
);
2990 ret
= fs_path_add_path(p
, name
);
2994 ret
= record_ref(&sctx
->new_refs
, dir
, gen
, p
);
3002 static int __record_deleted_ref(int num
, u64 dir
, int index
,
3003 struct fs_path
*name
,
3007 struct send_ctx
*sctx
= ctx
;
3011 p
= fs_path_alloc();
3015 ret
= get_inode_info(sctx
->parent_root
, dir
, NULL
, &gen
, NULL
, NULL
,
3020 ret
= get_cur_path(sctx
, dir
, gen
, p
);
3023 ret
= fs_path_add_path(p
, name
);
3027 ret
= record_ref(&sctx
->deleted_refs
, dir
, gen
, p
);
3035 static int record_new_ref(struct send_ctx
*sctx
)
3039 ret
= iterate_inode_ref(sctx
->send_root
, sctx
->left_path
,
3040 sctx
->cmp_key
, 0, __record_new_ref
, sctx
);
3049 static int record_deleted_ref(struct send_ctx
*sctx
)
3053 ret
= iterate_inode_ref(sctx
->parent_root
, sctx
->right_path
,
3054 sctx
->cmp_key
, 0, __record_deleted_ref
, sctx
);
3063 struct find_ref_ctx
{
3066 struct btrfs_root
*root
;
3067 struct fs_path
*name
;
3071 static int __find_iref(int num
, u64 dir
, int index
,
3072 struct fs_path
*name
,
3075 struct find_ref_ctx
*ctx
= ctx_
;
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) {
3082 * To avoid doing extra lookups we'll only do this if everything
3085 ret
= get_inode_info(ctx
->root
, dir
, NULL
, &dir_gen
, NULL
,
3089 if (dir_gen
!= ctx
->dir_gen
)
3091 ctx
->found_idx
= num
;
3097 static int find_iref(struct btrfs_root
*root
,
3098 struct btrfs_path
*path
,
3099 struct btrfs_key
*key
,
3100 u64 dir
, u64 dir_gen
, struct fs_path
*name
)
3103 struct find_ref_ctx ctx
;
3107 ctx
.dir_gen
= dir_gen
;
3111 ret
= iterate_inode_ref(root
, path
, key
, 0, __find_iref
, &ctx
);
3115 if (ctx
.found_idx
== -1)
3118 return ctx
.found_idx
;
3121 static int __record_changed_new_ref(int num
, u64 dir
, int index
,
3122 struct fs_path
*name
,
3127 struct send_ctx
*sctx
= ctx
;
3129 ret
= get_inode_info(sctx
->send_root
, dir
, NULL
, &dir_gen
, NULL
,
3134 ret
= find_iref(sctx
->parent_root
, sctx
->right_path
,
3135 sctx
->cmp_key
, dir
, dir_gen
, name
);
3137 ret
= __record_new_ref(num
, dir
, index
, name
, sctx
);
3144 static int __record_changed_deleted_ref(int num
, u64 dir
, int index
,
3145 struct fs_path
*name
,
3150 struct send_ctx
*sctx
= ctx
;
3152 ret
= get_inode_info(sctx
->parent_root
, dir
, NULL
, &dir_gen
, NULL
,
3157 ret
= find_iref(sctx
->send_root
, sctx
->left_path
, sctx
->cmp_key
,
3158 dir
, dir_gen
, name
);
3160 ret
= __record_deleted_ref(num
, dir
, index
, name
, sctx
);
3167 static int record_changed_ref(struct send_ctx
*sctx
)
3171 ret
= iterate_inode_ref(sctx
->send_root
, sctx
->left_path
,
3172 sctx
->cmp_key
, 0, __record_changed_new_ref
, sctx
);
3175 ret
= iterate_inode_ref(sctx
->parent_root
, sctx
->right_path
,
3176 sctx
->cmp_key
, 0, __record_changed_deleted_ref
, sctx
);
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.
3189 static int process_all_refs(struct send_ctx
*sctx
,
3190 enum btrfs_compare_tree_result cmd
)
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
;
3199 iterate_inode_ref_t cb
;
3201 path
= alloc_path_for_send();
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
;
3215 key
.objectid
= sctx
->cmp_key
->objectid
;
3216 key
.type
= BTRFS_INODE_REF_KEY
;
3219 ret
= btrfs_search_slot_for_read(root
, &key
, path
, 1, 0);
3225 eb
= path
->nodes
[0];
3226 slot
= path
->slots
[0];
3227 btrfs_item_key_to_cpu(eb
, &found_key
, slot
);
3229 if (found_key
.objectid
!= key
.objectid
||
3230 (found_key
.type
!= BTRFS_INODE_REF_KEY
&&
3231 found_key
.type
!= BTRFS_INODE_EXTREF_KEY
))
3234 ret
= iterate_inode_ref(root
, path
, &found_key
, 0, cb
, sctx
);
3235 btrfs_release_path(path
);
3239 key
.offset
= found_key
.offset
+ 1;
3241 btrfs_release_path(path
);
3243 ret
= process_recorded_refs(sctx
);
3246 btrfs_free_path(path
);
3250 static 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
)
3257 ret
= begin_cmd(sctx
, BTRFS_SEND_C_SET_XATTR
);
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
);
3265 ret
= send_cmd(sctx
);
3272 static int send_remove_xattr(struct send_ctx
*sctx
,
3273 struct fs_path
*path
,
3274 const char *name
, int name_len
)
3278 ret
= begin_cmd(sctx
, BTRFS_SEND_C_REMOVE_XATTR
);
3282 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, path
);
3283 TLV_PUT_STRING(sctx
, BTRFS_SEND_A_XATTR_NAME
, name
, name_len
);
3285 ret
= send_cmd(sctx
);
3292 static 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
,
3298 struct send_ctx
*sctx
= ctx
;
3300 posix_acl_xattr_header dummy_acl
;
3302 p
= fs_path_alloc();
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.
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
);
3322 ret
= get_cur_path(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
, p
);
3326 ret
= send_set_xattr(sctx
, p
, name
, name_len
, data
, data_len
);
3333 static 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
,
3339 struct send_ctx
*sctx
= ctx
;
3342 p
= fs_path_alloc();
3346 ret
= get_cur_path(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
, p
);
3350 ret
= send_remove_xattr(sctx
, p
, name
, name_len
);
3357 static int process_new_xattr(struct send_ctx
*sctx
)
3361 ret
= iterate_dir_item(sctx
->send_root
, sctx
->left_path
,
3362 sctx
->cmp_key
, __process_new_xattr
, sctx
);
3367 static int process_deleted_xattr(struct send_ctx
*sctx
)
3371 ret
= iterate_dir_item(sctx
->parent_root
, sctx
->right_path
,
3372 sctx
->cmp_key
, __process_deleted_xattr
, sctx
);
3377 struct find_xattr_ctx
{
3385 static 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
)
3390 struct find_xattr_ctx
*ctx
= vctx
;
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
;
3396 ctx
->found_data
= kmemdup(data
, data_len
, GFP_NOFS
);
3397 if (!ctx
->found_data
)
3404 static int find_xattr(struct btrfs_root
*root
,
3405 struct btrfs_path
*path
,
3406 struct btrfs_key
*key
,
3407 const char *name
, int name_len
,
3408 char **data
, int *data_len
)
3411 struct find_xattr_ctx ctx
;
3414 ctx
.name_len
= name_len
;
3416 ctx
.found_data
= NULL
;
3417 ctx
.found_data_len
= 0;
3419 ret
= iterate_dir_item(root
, path
, key
, __find_xattr
, &ctx
);
3423 if (ctx
.found_idx
== -1)
3426 *data
= ctx
.found_data
;
3427 *data_len
= ctx
.found_data_len
;
3429 kfree(ctx
.found_data
);
3431 return ctx
.found_idx
;
3435 static 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
,
3441 struct send_ctx
*sctx
= ctx
;
3442 char *found_data
= NULL
;
3443 int found_data_len
= 0;
3445 ret
= find_xattr(sctx
->parent_root
, sctx
->right_path
,
3446 sctx
->cmp_key
, name
, name_len
, &found_data
,
3448 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
);
3465 static 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
,
3471 struct send_ctx
*sctx
= ctx
;
3473 ret
= find_xattr(sctx
->send_root
, sctx
->left_path
, sctx
->cmp_key
,
3474 name
, name_len
, NULL
, NULL
);
3476 ret
= __process_deleted_xattr(num
, di_key
, name
, name_len
, data
,
3477 data_len
, type
, ctx
);
3484 static int process_changed_xattr(struct send_ctx
*sctx
)
3488 ret
= iterate_dir_item(sctx
->send_root
, sctx
->left_path
,
3489 sctx
->cmp_key
, __process_changed_new_xattr
, sctx
);
3492 ret
= iterate_dir_item(sctx
->parent_root
, sctx
->right_path
,
3493 sctx
->cmp_key
, __process_changed_deleted_xattr
, sctx
);
3499 static int process_all_new_xattrs(struct send_ctx
*sctx
)
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
;
3509 path
= alloc_path_for_send();
3513 root
= sctx
->send_root
;
3515 key
.objectid
= sctx
->cmp_key
->objectid
;
3516 key
.type
= BTRFS_XATTR_ITEM_KEY
;
3519 ret
= btrfs_search_slot_for_read(root
, &key
, path
, 1, 0);
3527 eb
= path
->nodes
[0];
3528 slot
= path
->slots
[0];
3529 btrfs_item_key_to_cpu(eb
, &found_key
, slot
);
3531 if (found_key
.objectid
!= key
.objectid
||
3532 found_key
.type
!= key
.type
) {
3537 ret
= iterate_dir_item(root
, path
, &found_key
,
3538 __process_new_xattr
, sctx
);
3542 btrfs_release_path(path
);
3543 key
.offset
= found_key
.offset
+ 1;
3547 btrfs_free_path(path
);
3551 static ssize_t
fill_read_buf(struct send_ctx
*sctx
, u64 offset
, u32 len
)
3553 struct btrfs_root
*root
= sctx
->send_root
;
3554 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
3555 struct inode
*inode
;
3558 struct btrfs_key key
;
3559 pgoff_t index
= offset
>> PAGE_CACHE_SHIFT
;
3561 unsigned pg_offset
= offset
& ~PAGE_CACHE_MASK
;
3564 key
.objectid
= sctx
->cur_ino
;
3565 key
.type
= BTRFS_INODE_ITEM_KEY
;
3568 inode
= btrfs_iget(fs_info
->sb
, &key
, root
, NULL
);
3570 return PTR_ERR(inode
);
3572 if (offset
+ len
> i_size_read(inode
)) {
3573 if (offset
> i_size_read(inode
))
3576 len
= offset
- i_size_read(inode
);
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
);
3591 if (!PageUptodate(page
)) {
3592 btrfs_readpage(NULL
, page
);
3594 if (!PageUptodate(page
)) {
3596 page_cache_release(page
);
3603 memcpy(sctx
->read_buf
+ ret
, addr
+ pg_offset
, cur_len
);
3606 page_cache_release(page
);
3618 * Read some bytes from the current inode/file and send a write command to
3621 static int send_write(struct send_ctx
*sctx
, u64 offset
, u32 len
)
3625 ssize_t num_read
= 0;
3627 p
= fs_path_alloc();
3631 verbose_printk("btrfs: send_write offset=%llu, len=%d\n", offset
, len
);
3633 num_read
= fill_read_buf(sctx
, offset
, len
);
3634 if (num_read
<= 0) {
3640 ret
= begin_cmd(sctx
, BTRFS_SEND_C_WRITE
);
3644 ret
= get_cur_path(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
, p
);
3648 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, p
);
3649 TLV_PUT_U64(sctx
, BTRFS_SEND_A_FILE_OFFSET
, offset
);
3650 TLV_PUT(sctx
, BTRFS_SEND_A_DATA
, sctx
->read_buf
, num_read
);
3652 ret
= send_cmd(sctx
);
3663 * Send a clone command to user space.
3665 static int send_clone(struct send_ctx
*sctx
,
3666 u64 offset
, u32 len
,
3667 struct clone_root
*clone_root
)
3673 verbose_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
);
3678 p
= fs_path_alloc();
3682 ret
= begin_cmd(sctx
, BTRFS_SEND_C_CLONE
);
3686 ret
= get_cur_path(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
, p
);
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
);
3694 if (clone_root
->root
== sctx
->send_root
) {
3695 ret
= get_inode_info(sctx
->send_root
, clone_root
->ino
, NULL
,
3696 &gen
, NULL
, NULL
, NULL
, NULL
);
3699 ret
= get_cur_path(sctx
, clone_root
->ino
, gen
, p
);
3701 ret
= get_inode_path(clone_root
->root
, clone_root
->ino
, p
);
3706 TLV_PUT_UUID(sctx
, BTRFS_SEND_A_CLONE_UUID
,
3707 clone_root
->root
->root_item
.uuid
);
3708 TLV_PUT_U64(sctx
, BTRFS_SEND_A_CLONE_CTRANSID
,
3709 clone_root
->root
->root_item
.ctransid
);
3710 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_CLONE_PATH
, p
);
3711 TLV_PUT_U64(sctx
, BTRFS_SEND_A_CLONE_OFFSET
,
3712 clone_root
->offset
);
3714 ret
= send_cmd(sctx
);
3723 * Send an update extent command to user space.
3725 static int send_update_extent(struct send_ctx
*sctx
,
3726 u64 offset
, u32 len
)
3731 p
= fs_path_alloc();
3735 ret
= begin_cmd(sctx
, BTRFS_SEND_C_UPDATE_EXTENT
);
3739 ret
= get_cur_path(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
, p
);
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
);
3747 ret
= send_cmd(sctx
);
3755 static 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
)
3761 struct btrfs_file_extent_item
*ei
;
3762 u64 offset
= key
->offset
;
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
);
3771 if (type
== BTRFS_FILE_EXTENT_INLINE
) {
3772 len
= btrfs_file_extent_inline_len(path
->nodes
[0], ei
);
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
3778 len
= PAGE_CACHE_ALIGN(len
);
3780 len
= btrfs_file_extent_num_bytes(path
->nodes
[0], ei
);
3783 if (offset
+ len
> sctx
->cur_inode_size
)
3784 len
= sctx
->cur_inode_size
- offset
;
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
);
3797 if (l
> BTRFS_SEND_READ_SIZE
)
3798 l
= BTRFS_SEND_READ_SIZE
;
3799 ret
= send_write(sctx
, pos
+ offset
, l
);
3812 static int is_extent_unchanged(struct send_ctx
*sctx
,
3813 struct btrfs_path
*left_path
,
3814 struct btrfs_key
*ekey
)
3817 struct btrfs_key key
;
3818 struct btrfs_path
*path
= NULL
;
3819 struct extent_buffer
*eb
;
3821 struct btrfs_key found_key
;
3822 struct btrfs_file_extent_item
*ei
;
3827 u64 left_offset_fixed
;
3835 path
= alloc_path_for_send();
3839 eb
= left_path
->nodes
[0];
3840 slot
= left_path
->slots
[0];
3841 ei
= btrfs_item_ptr(eb
, slot
, struct btrfs_file_extent_item
);
3842 left_type
= btrfs_file_extent_type(eb
, ei
);
3844 if (left_type
!= BTRFS_FILE_EXTENT_REG
) {
3848 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
);
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.
3859 * |-1-|-2a-|-3-|-4-|-5-|-6-|
3862 * |--1--|-2b-|...(same as above)
3864 * Alternative situation. Happens on files where extents got split.
3866 * |-----------7-----------|-6-|
3868 * Alternative situation. Happens on files which got larger.
3871 * Nothing follows after 8.
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);
3886 * Handle special case where the right side has no extents at all.
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
) {
3893 /* If we're a hole then just pretend nothing changed */
3894 ret
= (left_disknr
) ? 0 : 1;
3899 * We're now on 2a, 2b or 7.
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
);
3905 if (right_type
!= BTRFS_FILE_EXTENT_REG
) {
3910 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
);
3916 * Are we at extent 8? If yes, we know the extent is changed.
3917 * This may only happen on the first iteration.
3919 if (found_key
.offset
+ right_len
<= ekey
->offset
) {
3920 /* If we're a hole just pretend nothing changed */
3921 ret
= (left_disknr
) ? 0 : 1;
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
;
3930 /* Fix the left offset for all behind 2a and 2b */
3931 left_offset_fixed
+= key
.offset
- ekey
->offset
;
3935 * Check if we have the same extent.
3937 if (left_disknr
!= right_disknr
||
3938 left_offset_fixed
!= right_offset
||
3939 left_gen
!= right_gen
) {
3945 * Go to the next extent.
3947 ret
= btrfs_next_item(sctx
->parent_root
, path
);
3951 eb
= path
->nodes
[0];
3952 slot
= path
->slots
[0];
3953 btrfs_item_key_to_cpu(eb
, &found_key
, slot
);
3955 if (ret
|| found_key
.objectid
!= key
.objectid
||
3956 found_key
.type
!= key
.type
) {
3957 key
.offset
+= right_len
;
3960 if (found_key
.offset
!= key
.offset
+ right_len
) {
3968 * We're now behind the left extent (treat as unchanged) or at the end
3969 * of the right side (treat as changed).
3971 if (key
.offset
>= ekey
->offset
+ left_len
)
3978 btrfs_free_path(path
);
3982 static int process_extent(struct send_ctx
*sctx
,
3983 struct btrfs_path
*path
,
3984 struct btrfs_key
*key
)
3986 struct clone_root
*found_clone
= NULL
;
3989 if (S_ISLNK(sctx
->cur_inode_mode
))
3992 if (sctx
->parent_root
&& !sctx
->cur_inode_new
) {
3993 ret
= is_extent_unchanged(sctx
, path
, key
);
4001 struct btrfs_file_extent_item
*ei
;
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
) {
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
4015 if (type
== BTRFS_FILE_EXTENT_PREALLOC
) {
4020 /* Have a hole, just skip it. */
4021 if (btrfs_file_extent_disk_bytenr(path
->nodes
[0], ei
) == 0) {
4028 ret
= find_extent_clone(sctx
, path
, key
->objectid
, key
->offset
,
4029 sctx
->cur_inode_size
, &found_clone
);
4030 if (ret
!= -ENOENT
&& ret
< 0)
4033 ret
= send_write_or_clone(sctx
, path
, key
, found_clone
);
4039 static int process_all_extents(struct send_ctx
*sctx
)
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
;
4049 root
= sctx
->send_root
;
4050 path
= alloc_path_for_send();
4054 key
.objectid
= sctx
->cmp_key
->objectid
;
4055 key
.type
= BTRFS_EXTENT_DATA_KEY
;
4058 ret
= btrfs_search_slot_for_read(root
, &key
, path
, 1, 0);
4066 eb
= path
->nodes
[0];
4067 slot
= path
->slots
[0];
4068 btrfs_item_key_to_cpu(eb
, &found_key
, slot
);
4070 if (found_key
.objectid
!= key
.objectid
||
4071 found_key
.type
!= key
.type
) {
4076 ret
= process_extent(sctx
, path
, &found_key
);
4080 btrfs_release_path(path
);
4081 key
.offset
= found_key
.offset
+ 1;
4085 btrfs_free_path(path
);
4089 static int process_recorded_refs_if_needed(struct send_ctx
*sctx
, int at_end
)
4093 if (sctx
->cur_ino
== 0)
4095 if (!at_end
&& sctx
->cur_ino
== sctx
->cmp_key
->objectid
&&
4096 sctx
->cmp_key
->type
<= BTRFS_INODE_EXTREF_KEY
)
4098 if (list_empty(&sctx
->new_refs
) && list_empty(&sctx
->deleted_refs
))
4101 ret
= process_recorded_refs(sctx
);
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.
4110 sctx
->send_progress
= sctx
->cur_ino
+ 1;
4116 static int finish_inode_if_needed(struct send_ctx
*sctx
, int at_end
)
4128 ret
= process_recorded_refs_if_needed(sctx
, at_end
);
4132 if (sctx
->cur_ino
== 0 || sctx
->cur_inode_deleted
)
4134 if (!at_end
&& sctx
->cmp_key
->objectid
== sctx
->cur_ino
)
4137 ret
= get_inode_info(sctx
->send_root
, sctx
->cur_ino
, NULL
, NULL
,
4138 &left_mode
, &left_uid
, &left_gid
, NULL
);
4142 if (!sctx
->parent_root
|| sctx
->cur_inode_new
) {
4144 if (!S_ISLNK(sctx
->cur_inode_mode
))
4147 ret
= get_inode_info(sctx
->parent_root
, sctx
->cur_ino
,
4148 NULL
, NULL
, &right_mode
, &right_uid
,
4153 if (left_uid
!= right_uid
|| left_gid
!= right_gid
)
4155 if (!S_ISLNK(sctx
->cur_inode_mode
) && left_mode
!= right_mode
)
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
);
4167 ret
= send_chown(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
,
4168 left_uid
, left_gid
);
4173 ret
= send_chmod(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
,
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.
4183 ret
= send_utimes(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
);
4191 static int changed_inode(struct send_ctx
*sctx
,
4192 enum btrfs_compare_tree_result result
)
4195 struct btrfs_key
*key
= sctx
->cmp_key
;
4196 struct btrfs_inode_item
*left_ii
= NULL
;
4197 struct btrfs_inode_item
*right_ii
= NULL
;
4201 sctx
->cur_ino
= key
->objectid
;
4202 sctx
->cur_inode_new_gen
= 0;
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.
4209 sctx
->send_progress
= sctx
->cur_ino
;
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],
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],
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
);
4230 right_gen
= btrfs_inode_generation(sctx
->right_path
->nodes
[0],
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.
4238 if (left_gen
!= right_gen
&&
4239 sctx
->cur_ino
!= BTRFS_FIRST_FREE_OBJECTID
)
4240 sctx
->cur_inode_new_gen
= 1;
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
)
4252 ret
= send_create_inode_if_needed(sctx
);
4253 } 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
) {
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.
4269 if (sctx
->cur_inode_new_gen
) {
4271 * First, process the inode as if it was deleted.
4273 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
);
4286 * Now process the inode as if it was new.
4288 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
);
4295 ret
= send_create_inode_if_needed(sctx
);
4299 ret
= process_all_refs(sctx
, BTRFS_COMPARE_TREE_NEW
);
4303 * Advance send_progress now as we did not get into
4304 * process_recorded_refs_if_needed in the new_gen case.
4306 sctx
->send_progress
= sctx
->cur_ino
+ 1;
4309 * Now process all extents and xattrs of the inode as if
4310 * they were all new.
4312 ret
= process_all_extents(sctx
);
4315 ret
= process_all_new_xattrs(sctx
);
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
);
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.
4344 static int changed_ref(struct send_ctx
*sctx
,
4345 enum btrfs_compare_tree_result result
)
4349 BUG_ON(sctx
->cur_ino
!= sctx
->cmp_key
->objectid
);
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
);
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
4369 static int changed_xattr(struct send_ctx
*sctx
,
4370 enum btrfs_compare_tree_result result
)
4374 BUG_ON(sctx
->cur_ino
!= sctx
->cmp_key
->objectid
);
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
);
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
4393 static int changed_extent(struct send_ctx
*sctx
,
4394 enum btrfs_compare_tree_result result
)
4398 BUG_ON(sctx
->cur_ino
!= sctx
->cmp_key
->objectid
);
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
,
4409 static int dir_changed(struct send_ctx
*sctx
, u64 dir
)
4411 u64 orig_gen
, new_gen
;
4414 ret
= get_inode_info(sctx
->send_root
, dir
, NULL
, &new_gen
, NULL
, NULL
,
4419 ret
= get_inode_info(sctx
->parent_root
, dir
, NULL
, &orig_gen
, NULL
,
4424 return (orig_gen
!= new_gen
) ? 1 : 0;
4427 static int compare_refs(struct send_ctx
*sctx
, struct btrfs_path
*path
,
4428 struct btrfs_key
*key
)
4430 struct btrfs_inode_extref
*extref
;
4431 struct extent_buffer
*leaf
;
4432 u64 dirid
= 0, last_dirid
= 0;
4439 /* Easy case, just check this one dirid */
4440 if (key
->type
== BTRFS_INODE_REF_KEY
) {
4441 dirid
= key
->offset
;
4443 ret
= dir_changed(sctx
, dirid
);
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
+
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
)
4458 ret
= dir_changed(sctx
, dirid
);
4468 * Updates compare related fields in sctx and simply forwards to the actual
4469 * changed_xxx functions.
4471 static 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
,
4480 struct send_ctx
*sctx
= ctx
;
4482 if (result
== BTRFS_COMPARE_TREE_SAME
) {
4483 if (key
->type
!= BTRFS_INODE_REF_KEY
&&
4484 key
->type
!= BTRFS_INODE_EXTREF_KEY
)
4486 ret
= compare_refs(sctx
, left_path
, key
);
4491 result
= BTRFS_COMPARE_TREE_CHANGED
;
4495 sctx
->left_path
= left_path
;
4496 sctx
->right_path
= right_path
;
4497 sctx
->cmp_key
= key
;
4499 ret
= finish_inode_if_needed(sctx
, 0);
4503 /* Ignore non-FS objects */
4504 if (key
->objectid
== BTRFS_FREE_INO_OBJECTID
||
4505 key
->objectid
== BTRFS_FREE_SPACE_OBJECTID
)
4508 if (key
->type
== BTRFS_INODE_ITEM_KEY
)
4509 ret
= changed_inode(sctx
, result
);
4510 else if (key
->type
== BTRFS_INODE_REF_KEY
||
4511 key
->type
== BTRFS_INODE_EXTREF_KEY
)
4512 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
);
4522 static int full_send_tree(struct send_ctx
*sctx
)
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
;
4535 path
= alloc_path_for_send();
4539 spin_lock(&send_root
->root_item_lock
);
4540 start_ctransid
= btrfs_root_ctransid(&send_root
->root_item
);
4541 spin_unlock(&send_root
->root_item_lock
);
4543 key
.objectid
= BTRFS_FIRST_FREE_OBJECTID
;
4544 key
.type
= BTRFS_INODE_ITEM_KEY
;
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
4553 trans
= btrfs_join_transaction(send_root
);
4554 if (IS_ERR(trans
)) {
4555 ret
= PTR_ERR(trans
);
4561 * Make sure the tree has not changed after re-joining. We detect this
4562 * by comparing start_ctransid and ctransid. They should always match.
4564 spin_lock(&send_root
->root_item_lock
);
4565 ctransid
= btrfs_root_ctransid(&send_root
->root_item
);
4566 spin_unlock(&send_root
->root_item_lock
);
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");
4576 ret
= btrfs_search_slot_for_read(send_root
, &key
, path
, 1, 0);
4584 * When someone want to commit while we iterate, end the
4585 * joined transaction and rejoin.
4587 if (btrfs_should_end_transaction(trans
, send_root
)) {
4588 ret
= btrfs_end_transaction(trans
, send_root
);
4592 btrfs_release_path(path
);
4596 eb
= path
->nodes
[0];
4597 slot
= path
->slots
[0];
4598 btrfs_item_key_to_cpu(eb
, &found_key
, slot
);
4600 ret
= changed_cb(send_root
, NULL
, path
, NULL
,
4601 &found_key
, BTRFS_COMPARE_TREE_NEW
, sctx
);
4605 key
.objectid
= found_key
.objectid
;
4606 key
.type
= found_key
.type
;
4607 key
.offset
= found_key
.offset
+ 1;
4609 ret
= btrfs_next_item(send_root
, path
);
4619 ret
= finish_inode_if_needed(sctx
, 1);
4622 btrfs_free_path(path
);
4625 ret
= btrfs_end_transaction(trans
, send_root
);
4627 btrfs_end_transaction(trans
, send_root
);
4632 static int send_subvol(struct send_ctx
*sctx
)
4636 if (!(sctx
->flags
& BTRFS_SEND_FLAG_OMIT_STREAM_HEADER
)) {
4637 ret
= send_header(sctx
);
4642 ret
= send_subvol_begin(sctx
);
4646 if (sctx
->parent_root
) {
4647 ret
= btrfs_compare_trees(sctx
->send_root
, sctx
->parent_root
,
4651 ret
= finish_inode_if_needed(sctx
, 1);
4655 ret
= full_send_tree(sctx
);
4661 free_recorded_refs(sctx
);
4665 long btrfs_ioctl_send(struct file
*mnt_file
, void __user
*arg_
)
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
;
4673 struct send_ctx
*sctx
= NULL
;
4675 u64
*clone_sources_tmp
= NULL
;
4677 if (!capable(CAP_SYS_ADMIN
))
4680 send_root
= BTRFS_I(file_inode(mnt_file
))->root
;
4681 fs_info
= send_root
->fs_info
;
4684 * This is done when we lookup the root, it should already be complete
4685 * by the time we get here.
4687 WARN_ON(send_root
->orphan_cleanup_state
!= ORPHAN_CLEANUP_DONE
);
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.
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
;
4700 up_read(&send_root
->fs_info
->extent_commit_sem
);
4702 trans
= btrfs_attach_transaction_barrier(send_root
);
4703 if (IS_ERR(trans
)) {
4704 if (PTR_ERR(trans
) != -ENOENT
) {
4705 ret
= PTR_ERR(trans
);
4708 /* ENOENT means theres no transaction */
4710 ret
= btrfs_commit_transaction(trans
, send_root
);
4715 up_read(&send_root
->fs_info
->extent_commit_sem
);
4718 arg
= memdup_user(arg_
, sizeof(*arg
));
4725 if (!access_ok(VERIFY_READ
, arg
->clone_sources
,
4726 sizeof(*arg
->clone_sources
*
4727 arg
->clone_sources_count
))) {
4732 if (arg
->flags
& ~BTRFS_SEND_FLAG_MASK
) {
4737 sctx
= kzalloc(sizeof(struct send_ctx
), GFP_NOFS
);
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
);
4748 sctx
->flags
= arg
->flags
;
4750 sctx
->send_filp
= fget(arg
->send_fd
);
4751 if (!sctx
->send_filp
) {
4756 sctx
->mnt
= mnt_file
->f_path
.mnt
;
4758 sctx
->send_root
= send_root
;
4759 sctx
->clone_roots_cnt
= arg
->clone_sources_count
;
4761 sctx
->send_max_size
= BTRFS_SEND_BUF_SIZE
;
4762 sctx
->send_buf
= vmalloc(sctx
->send_max_size
);
4763 if (!sctx
->send_buf
) {
4768 sctx
->read_buf
= vmalloc(BTRFS_SEND_READ_SIZE
);
4769 if (!sctx
->read_buf
) {
4774 sctx
->clone_roots
= vzalloc(sizeof(struct clone_root
) *
4775 (arg
->clone_sources_count
+ 1));
4776 if (!sctx
->clone_roots
) {
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
) {
4789 ret
= copy_from_user(clone_sources_tmp
, arg
->clone_sources
,
4790 arg
->clone_sources_count
*
4791 sizeof(*arg
->clone_sources
));
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
);
4802 if (IS_ERR(clone_root
)) {
4803 ret
= PTR_ERR(clone_root
);
4806 sctx
->clone_roots
[i
].root
= clone_root
;
4808 vfree(clone_sources_tmp
);
4809 clone_sources_tmp
= NULL
;
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
);
4817 if (IS_ERR(sctx
->parent_root
)) {
4818 ret
= PTR_ERR(sctx
->parent_root
);
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.
4828 sctx
->clone_roots
[sctx
->clone_roots_cnt
++].root
= sctx
->send_root
;
4830 /* We do a bsearch later */
4831 sort(sctx
->clone_roots
, sctx
->clone_roots_cnt
,
4832 sizeof(*sctx
->clone_roots
), __clone_root_cmp_sort
,
4835 ret
= send_subvol(sctx
);
4839 if (!(sctx
->flags
& BTRFS_SEND_FLAG_OMIT_END_CMD
)) {
4840 ret
= begin_cmd(sctx
, BTRFS_SEND_C_END
);
4843 ret
= send_cmd(sctx
);
4850 vfree(clone_sources_tmp
);
4853 if (sctx
->send_filp
)
4854 fput(sctx
->send_filp
);
4856 vfree(sctx
->clone_roots
);
4857 vfree(sctx
->send_buf
);
4858 vfree(sctx
->read_buf
);
4860 name_cache_free(sctx
);