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/vmalloc.h>
28 #include <linux/string.h>
29 #include <linux/compat.h>
36 #include "btrfs_inode.h"
37 #include "transaction.h"
38 #include "compression.h"
41 * A fs_path is a helper to dynamically build path names with unknown size.
42 * It reallocates the internal buffer on demand.
43 * It allows fast adding of path elements on the right side (normal path) and
44 * fast adding to the left side (reversed path). A reversed path can also be
45 * unreversed if needed.
54 unsigned short buf_len
:15;
55 unsigned short reversed
:1;
59 * Average path length does not exceed 200 bytes, we'll have
60 * better packing in the slab and higher chance to satisfy
61 * a allocation later during send.
66 #define FS_PATH_INLINE_SIZE \
67 (sizeof(struct fs_path) - offsetof(struct fs_path, inline_buf))
70 /* reused for each extent */
72 struct btrfs_root
*root
;
79 #define SEND_CTX_MAX_NAME_CACHE_SIZE 128
80 #define SEND_CTX_NAME_CACHE_CLEAN_SIZE (SEND_CTX_MAX_NAME_CACHE_SIZE * 2)
83 struct file
*send_filp
;
89 u64 cmd_send_size
[BTRFS_SEND_C_MAX
+ 1];
90 u64 flags
; /* 'flags' member of btrfs_ioctl_send_args is u64 */
92 struct btrfs_root
*send_root
;
93 struct btrfs_root
*parent_root
;
94 struct clone_root
*clone_roots
;
97 /* current state of the compare_tree call */
98 struct btrfs_path
*left_path
;
99 struct btrfs_path
*right_path
;
100 struct btrfs_key
*cmp_key
;
103 * infos of the currently processed inode. In case of deleted inodes,
104 * these are the values from the deleted inode.
109 int cur_inode_new_gen
;
110 int cur_inode_deleted
;
114 u64 cur_inode_last_extent
;
118 struct list_head new_refs
;
119 struct list_head deleted_refs
;
121 struct radix_tree_root name_cache
;
122 struct list_head name_cache_list
;
125 struct file_ra_state ra
;
130 * We process inodes by their increasing order, so if before an
131 * incremental send we reverse the parent/child relationship of
132 * directories such that a directory with a lower inode number was
133 * the parent of a directory with a higher inode number, and the one
134 * becoming the new parent got renamed too, we can't rename/move the
135 * directory with lower inode number when we finish processing it - we
136 * must process the directory with higher inode number first, then
137 * rename/move it and then rename/move the directory with lower inode
138 * number. Example follows.
140 * Tree state when the first send was performed:
152 * Tree state when the second (incremental) send is performed:
161 * The sequence of steps that lead to the second state was:
163 * mv /a/b/c/d /a/b/c2/d2
164 * mv /a/b/c /a/b/c2/d2/cc
166 * "c" has lower inode number, but we can't move it (2nd mv operation)
167 * before we move "d", which has higher inode number.
169 * So we just memorize which move/rename operations must be performed
170 * later when their respective parent is processed and moved/renamed.
173 /* Indexed by parent directory inode number. */
174 struct rb_root pending_dir_moves
;
177 * Reverse index, indexed by the inode number of a directory that
178 * is waiting for the move/rename of its immediate parent before its
179 * own move/rename can be performed.
181 struct rb_root waiting_dir_moves
;
184 * A directory that is going to be rm'ed might have a child directory
185 * which is in the pending directory moves index above. In this case,
186 * the directory can only be removed after the move/rename of its child
187 * is performed. Example:
207 * Sequence of steps that lead to the send snapshot:
208 * rm -f /a/b/c/foo.txt
210 * mv /a/b/c/x /a/b/YY
213 * When the child is processed, its move/rename is delayed until its
214 * parent is processed (as explained above), but all other operations
215 * like update utimes, chown, chgrp, etc, are performed and the paths
216 * that it uses for those operations must use the orphanized name of
217 * its parent (the directory we're going to rm later), so we need to
218 * memorize that name.
220 * Indexed by the inode number of the directory to be deleted.
222 struct rb_root orphan_dirs
;
225 struct pending_dir_move
{
227 struct list_head list
;
231 struct list_head update_refs
;
234 struct waiting_dir_move
{
238 * There might be some directory that could not be removed because it
239 * was waiting for this directory inode to be moved first. Therefore
240 * after this directory is moved, we can try to rmdir the ino rmdir_ino.
246 struct orphan_dir_info
{
252 struct name_cache_entry
{
253 struct list_head list
;
255 * radix_tree has only 32bit entries but we need to handle 64bit inums.
256 * We use the lower 32bit of the 64bit inum to store it in the tree. If
257 * more then one inum would fall into the same entry, we use radix_list
258 * to store the additional entries. radix_list is also used to store
259 * entries where two entries have the same inum but different
262 struct list_head radix_list
;
268 int need_later_update
;
273 static void inconsistent_snapshot_error(struct send_ctx
*sctx
,
274 enum btrfs_compare_tree_result result
,
277 const char *result_string
;
280 case BTRFS_COMPARE_TREE_NEW
:
281 result_string
= "new";
283 case BTRFS_COMPARE_TREE_DELETED
:
284 result_string
= "deleted";
286 case BTRFS_COMPARE_TREE_CHANGED
:
287 result_string
= "updated";
289 case BTRFS_COMPARE_TREE_SAME
:
291 result_string
= "unchanged";
295 result_string
= "unexpected";
298 btrfs_err(sctx
->send_root
->fs_info
,
299 "Send: inconsistent snapshot, found %s %s for inode %llu without updated inode item, send root is %llu, parent root is %llu",
300 result_string
, what
, sctx
->cmp_key
->objectid
,
301 sctx
->send_root
->root_key
.objectid
,
303 sctx
->parent_root
->root_key
.objectid
: 0));
306 static int is_waiting_for_move(struct send_ctx
*sctx
, u64 ino
);
308 static struct waiting_dir_move
*
309 get_waiting_dir_move(struct send_ctx
*sctx
, u64 ino
);
311 static int is_waiting_for_rm(struct send_ctx
*sctx
, u64 dir_ino
);
313 static int need_send_hole(struct send_ctx
*sctx
)
315 return (sctx
->parent_root
&& !sctx
->cur_inode_new
&&
316 !sctx
->cur_inode_new_gen
&& !sctx
->cur_inode_deleted
&&
317 S_ISREG(sctx
->cur_inode_mode
));
320 static void fs_path_reset(struct fs_path
*p
)
323 p
->start
= p
->buf
+ p
->buf_len
- 1;
333 static struct fs_path
*fs_path_alloc(void)
337 p
= kmalloc(sizeof(*p
), GFP_KERNEL
);
341 p
->buf
= p
->inline_buf
;
342 p
->buf_len
= FS_PATH_INLINE_SIZE
;
347 static struct fs_path
*fs_path_alloc_reversed(void)
359 static void fs_path_free(struct fs_path
*p
)
363 if (p
->buf
!= p
->inline_buf
)
368 static int fs_path_len(struct fs_path
*p
)
370 return p
->end
- p
->start
;
373 static int fs_path_ensure_buf(struct fs_path
*p
, int len
)
381 if (p
->buf_len
>= len
)
384 if (len
> PATH_MAX
) {
389 path_len
= p
->end
- p
->start
;
390 old_buf_len
= p
->buf_len
;
393 * First time the inline_buf does not suffice
395 if (p
->buf
== p
->inline_buf
) {
396 tmp_buf
= kmalloc(len
, GFP_KERNEL
);
398 memcpy(tmp_buf
, p
->buf
, old_buf_len
);
400 tmp_buf
= krealloc(p
->buf
, len
, GFP_KERNEL
);
406 * The real size of the buffer is bigger, this will let the fast path
407 * happen most of the time
409 p
->buf_len
= ksize(p
->buf
);
412 tmp_buf
= p
->buf
+ old_buf_len
- path_len
- 1;
413 p
->end
= p
->buf
+ p
->buf_len
- 1;
414 p
->start
= p
->end
- path_len
;
415 memmove(p
->start
, tmp_buf
, path_len
+ 1);
418 p
->end
= p
->start
+ path_len
;
423 static int fs_path_prepare_for_add(struct fs_path
*p
, int name_len
,
429 new_len
= p
->end
- p
->start
+ name_len
;
430 if (p
->start
!= p
->end
)
432 ret
= fs_path_ensure_buf(p
, new_len
);
437 if (p
->start
!= p
->end
)
439 p
->start
-= name_len
;
440 *prepared
= p
->start
;
442 if (p
->start
!= p
->end
)
453 static int fs_path_add(struct fs_path
*p
, const char *name
, int name_len
)
458 ret
= fs_path_prepare_for_add(p
, name_len
, &prepared
);
461 memcpy(prepared
, name
, name_len
);
467 static int fs_path_add_path(struct fs_path
*p
, struct fs_path
*p2
)
472 ret
= fs_path_prepare_for_add(p
, p2
->end
- p2
->start
, &prepared
);
475 memcpy(prepared
, p2
->start
, p2
->end
- p2
->start
);
481 static int fs_path_add_from_extent_buffer(struct fs_path
*p
,
482 struct extent_buffer
*eb
,
483 unsigned long off
, int len
)
488 ret
= fs_path_prepare_for_add(p
, len
, &prepared
);
492 read_extent_buffer(eb
, prepared
, off
, len
);
498 static int fs_path_copy(struct fs_path
*p
, struct fs_path
*from
)
502 p
->reversed
= from
->reversed
;
505 ret
= fs_path_add_path(p
, from
);
511 static void fs_path_unreverse(struct fs_path
*p
)
520 len
= p
->end
- p
->start
;
522 p
->end
= p
->start
+ len
;
523 memmove(p
->start
, tmp
, len
+ 1);
527 static struct btrfs_path
*alloc_path_for_send(void)
529 struct btrfs_path
*path
;
531 path
= btrfs_alloc_path();
534 path
->search_commit_root
= 1;
535 path
->skip_locking
= 1;
536 path
->need_commit_sem
= 1;
540 static int write_buf(struct file
*filp
, const void *buf
, u32 len
, loff_t
*off
)
546 ret
= kernel_write(filp
, buf
+ pos
, len
- pos
, off
);
547 /* TODO handle that correctly */
548 /*if (ret == -ERESTARTSYS) {
562 static int tlv_put(struct send_ctx
*sctx
, u16 attr
, const void *data
, int len
)
564 struct btrfs_tlv_header
*hdr
;
565 int total_len
= sizeof(*hdr
) + len
;
566 int left
= sctx
->send_max_size
- sctx
->send_size
;
568 if (unlikely(left
< total_len
))
571 hdr
= (struct btrfs_tlv_header
*) (sctx
->send_buf
+ sctx
->send_size
);
572 hdr
->tlv_type
= cpu_to_le16(attr
);
573 hdr
->tlv_len
= cpu_to_le16(len
);
574 memcpy(hdr
+ 1, data
, len
);
575 sctx
->send_size
+= total_len
;
580 #define TLV_PUT_DEFINE_INT(bits) \
581 static int tlv_put_u##bits(struct send_ctx *sctx, \
582 u##bits attr, u##bits value) \
584 __le##bits __tmp = cpu_to_le##bits(value); \
585 return tlv_put(sctx, attr, &__tmp, sizeof(__tmp)); \
588 TLV_PUT_DEFINE_INT(64)
590 static int tlv_put_string(struct send_ctx
*sctx
, u16 attr
,
591 const char *str
, int len
)
595 return tlv_put(sctx
, attr
, str
, len
);
598 static int tlv_put_uuid(struct send_ctx
*sctx
, u16 attr
,
601 return tlv_put(sctx
, attr
, uuid
, BTRFS_UUID_SIZE
);
604 static int tlv_put_btrfs_timespec(struct send_ctx
*sctx
, u16 attr
,
605 struct extent_buffer
*eb
,
606 struct btrfs_timespec
*ts
)
608 struct btrfs_timespec bts
;
609 read_extent_buffer(eb
, &bts
, (unsigned long)ts
, sizeof(bts
));
610 return tlv_put(sctx
, attr
, &bts
, sizeof(bts
));
614 #define TLV_PUT(sctx, attrtype, attrlen, data) \
616 ret = tlv_put(sctx, attrtype, attrlen, data); \
618 goto tlv_put_failure; \
621 #define TLV_PUT_INT(sctx, attrtype, bits, value) \
623 ret = tlv_put_u##bits(sctx, attrtype, value); \
625 goto tlv_put_failure; \
628 #define TLV_PUT_U8(sctx, attrtype, data) TLV_PUT_INT(sctx, attrtype, 8, data)
629 #define TLV_PUT_U16(sctx, attrtype, data) TLV_PUT_INT(sctx, attrtype, 16, data)
630 #define TLV_PUT_U32(sctx, attrtype, data) TLV_PUT_INT(sctx, attrtype, 32, data)
631 #define TLV_PUT_U64(sctx, attrtype, data) TLV_PUT_INT(sctx, attrtype, 64, data)
632 #define TLV_PUT_STRING(sctx, attrtype, str, len) \
634 ret = tlv_put_string(sctx, attrtype, str, len); \
636 goto tlv_put_failure; \
638 #define TLV_PUT_PATH(sctx, attrtype, p) \
640 ret = tlv_put_string(sctx, attrtype, p->start, \
641 p->end - p->start); \
643 goto tlv_put_failure; \
645 #define TLV_PUT_UUID(sctx, attrtype, uuid) \
647 ret = tlv_put_uuid(sctx, attrtype, uuid); \
649 goto tlv_put_failure; \
651 #define TLV_PUT_BTRFS_TIMESPEC(sctx, attrtype, eb, ts) \
653 ret = tlv_put_btrfs_timespec(sctx, attrtype, eb, ts); \
655 goto tlv_put_failure; \
658 static int send_header(struct send_ctx
*sctx
)
660 struct btrfs_stream_header hdr
;
662 strcpy(hdr
.magic
, BTRFS_SEND_STREAM_MAGIC
);
663 hdr
.version
= cpu_to_le32(BTRFS_SEND_STREAM_VERSION
);
665 return write_buf(sctx
->send_filp
, &hdr
, sizeof(hdr
),
670 * For each command/item we want to send to userspace, we call this function.
672 static int begin_cmd(struct send_ctx
*sctx
, int cmd
)
674 struct btrfs_cmd_header
*hdr
;
676 if (WARN_ON(!sctx
->send_buf
))
679 BUG_ON(sctx
->send_size
);
681 sctx
->send_size
+= sizeof(*hdr
);
682 hdr
= (struct btrfs_cmd_header
*)sctx
->send_buf
;
683 hdr
->cmd
= cpu_to_le16(cmd
);
688 static int send_cmd(struct send_ctx
*sctx
)
691 struct btrfs_cmd_header
*hdr
;
694 hdr
= (struct btrfs_cmd_header
*)sctx
->send_buf
;
695 hdr
->len
= cpu_to_le32(sctx
->send_size
- sizeof(*hdr
));
698 crc
= btrfs_crc32c(0, (unsigned char *)sctx
->send_buf
, sctx
->send_size
);
699 hdr
->crc
= cpu_to_le32(crc
);
701 ret
= write_buf(sctx
->send_filp
, sctx
->send_buf
, sctx
->send_size
,
704 sctx
->total_send_size
+= sctx
->send_size
;
705 sctx
->cmd_send_size
[le16_to_cpu(hdr
->cmd
)] += sctx
->send_size
;
712 * Sends a move instruction to user space
714 static int send_rename(struct send_ctx
*sctx
,
715 struct fs_path
*from
, struct fs_path
*to
)
717 struct btrfs_fs_info
*fs_info
= sctx
->send_root
->fs_info
;
720 btrfs_debug(fs_info
, "send_rename %s -> %s", from
->start
, to
->start
);
722 ret
= begin_cmd(sctx
, BTRFS_SEND_C_RENAME
);
726 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, from
);
727 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH_TO
, to
);
729 ret
= send_cmd(sctx
);
737 * Sends a link instruction to user space
739 static int send_link(struct send_ctx
*sctx
,
740 struct fs_path
*path
, struct fs_path
*lnk
)
742 struct btrfs_fs_info
*fs_info
= sctx
->send_root
->fs_info
;
745 btrfs_debug(fs_info
, "send_link %s -> %s", path
->start
, lnk
->start
);
747 ret
= begin_cmd(sctx
, BTRFS_SEND_C_LINK
);
751 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, path
);
752 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH_LINK
, lnk
);
754 ret
= send_cmd(sctx
);
762 * Sends an unlink instruction to user space
764 static int send_unlink(struct send_ctx
*sctx
, struct fs_path
*path
)
766 struct btrfs_fs_info
*fs_info
= sctx
->send_root
->fs_info
;
769 btrfs_debug(fs_info
, "send_unlink %s", path
->start
);
771 ret
= begin_cmd(sctx
, BTRFS_SEND_C_UNLINK
);
775 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, path
);
777 ret
= send_cmd(sctx
);
785 * Sends a rmdir instruction to user space
787 static int send_rmdir(struct send_ctx
*sctx
, struct fs_path
*path
)
789 struct btrfs_fs_info
*fs_info
= sctx
->send_root
->fs_info
;
792 btrfs_debug(fs_info
, "send_rmdir %s", path
->start
);
794 ret
= begin_cmd(sctx
, BTRFS_SEND_C_RMDIR
);
798 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, path
);
800 ret
= send_cmd(sctx
);
808 * Helper function to retrieve some fields from an inode item.
810 static int __get_inode_info(struct btrfs_root
*root
, struct btrfs_path
*path
,
811 u64 ino
, u64
*size
, u64
*gen
, u64
*mode
, u64
*uid
,
815 struct btrfs_inode_item
*ii
;
816 struct btrfs_key key
;
819 key
.type
= BTRFS_INODE_ITEM_KEY
;
821 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
828 ii
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
829 struct btrfs_inode_item
);
831 *size
= btrfs_inode_size(path
->nodes
[0], ii
);
833 *gen
= btrfs_inode_generation(path
->nodes
[0], ii
);
835 *mode
= btrfs_inode_mode(path
->nodes
[0], ii
);
837 *uid
= btrfs_inode_uid(path
->nodes
[0], ii
);
839 *gid
= btrfs_inode_gid(path
->nodes
[0], ii
);
841 *rdev
= btrfs_inode_rdev(path
->nodes
[0], ii
);
846 static int get_inode_info(struct btrfs_root
*root
,
847 u64 ino
, u64
*size
, u64
*gen
,
848 u64
*mode
, u64
*uid
, u64
*gid
,
851 struct btrfs_path
*path
;
854 path
= alloc_path_for_send();
857 ret
= __get_inode_info(root
, path
, ino
, size
, gen
, mode
, uid
, gid
,
859 btrfs_free_path(path
);
863 typedef int (*iterate_inode_ref_t
)(int num
, u64 dir
, int index
,
868 * Helper function to iterate the entries in ONE btrfs_inode_ref or
869 * btrfs_inode_extref.
870 * The iterate callback may return a non zero value to stop iteration. This can
871 * be a negative value for error codes or 1 to simply stop it.
873 * path must point to the INODE_REF or INODE_EXTREF when called.
875 static int iterate_inode_ref(struct btrfs_root
*root
, struct btrfs_path
*path
,
876 struct btrfs_key
*found_key
, int resolve
,
877 iterate_inode_ref_t iterate
, void *ctx
)
879 struct extent_buffer
*eb
= path
->nodes
[0];
880 struct btrfs_item
*item
;
881 struct btrfs_inode_ref
*iref
;
882 struct btrfs_inode_extref
*extref
;
883 struct btrfs_path
*tmp_path
;
887 int slot
= path
->slots
[0];
894 unsigned long name_off
;
895 unsigned long elem_size
;
898 p
= fs_path_alloc_reversed();
902 tmp_path
= alloc_path_for_send();
909 if (found_key
->type
== BTRFS_INODE_REF_KEY
) {
910 ptr
= (unsigned long)btrfs_item_ptr(eb
, slot
,
911 struct btrfs_inode_ref
);
912 item
= btrfs_item_nr(slot
);
913 total
= btrfs_item_size(eb
, item
);
914 elem_size
= sizeof(*iref
);
916 ptr
= btrfs_item_ptr_offset(eb
, slot
);
917 total
= btrfs_item_size_nr(eb
, slot
);
918 elem_size
= sizeof(*extref
);
921 while (cur
< total
) {
924 if (found_key
->type
== BTRFS_INODE_REF_KEY
) {
925 iref
= (struct btrfs_inode_ref
*)(ptr
+ cur
);
926 name_len
= btrfs_inode_ref_name_len(eb
, iref
);
927 name_off
= (unsigned long)(iref
+ 1);
928 index
= btrfs_inode_ref_index(eb
, iref
);
929 dir
= found_key
->offset
;
931 extref
= (struct btrfs_inode_extref
*)(ptr
+ cur
);
932 name_len
= btrfs_inode_extref_name_len(eb
, extref
);
933 name_off
= (unsigned long)&extref
->name
;
934 index
= btrfs_inode_extref_index(eb
, extref
);
935 dir
= btrfs_inode_extref_parent(eb
, extref
);
939 start
= btrfs_ref_to_path(root
, tmp_path
, name_len
,
943 ret
= PTR_ERR(start
);
946 if (start
< p
->buf
) {
947 /* overflow , try again with larger buffer */
948 ret
= fs_path_ensure_buf(p
,
949 p
->buf_len
+ p
->buf
- start
);
952 start
= btrfs_ref_to_path(root
, tmp_path
,
957 ret
= PTR_ERR(start
);
960 BUG_ON(start
< p
->buf
);
964 ret
= fs_path_add_from_extent_buffer(p
, eb
, name_off
,
970 cur
+= elem_size
+ name_len
;
971 ret
= iterate(num
, dir
, index
, p
, ctx
);
978 btrfs_free_path(tmp_path
);
983 typedef int (*iterate_dir_item_t
)(int num
, struct btrfs_key
*di_key
,
984 const char *name
, int name_len
,
985 const char *data
, int data_len
,
989 * Helper function to iterate the entries in ONE btrfs_dir_item.
990 * The iterate callback may return a non zero value to stop iteration. This can
991 * be a negative value for error codes or 1 to simply stop it.
993 * path must point to the dir item when called.
995 static int iterate_dir_item(struct btrfs_root
*root
, struct btrfs_path
*path
,
996 iterate_dir_item_t iterate
, void *ctx
)
999 struct extent_buffer
*eb
;
1000 struct btrfs_item
*item
;
1001 struct btrfs_dir_item
*di
;
1002 struct btrfs_key di_key
;
1015 * Start with a small buffer (1 page). If later we end up needing more
1016 * space, which can happen for xattrs on a fs with a leaf size greater
1017 * then the page size, attempt to increase the buffer. Typically xattr
1021 buf
= kmalloc(buf_len
, GFP_KERNEL
);
1027 eb
= path
->nodes
[0];
1028 slot
= path
->slots
[0];
1029 item
= btrfs_item_nr(slot
);
1030 di
= btrfs_item_ptr(eb
, slot
, struct btrfs_dir_item
);
1033 total
= btrfs_item_size(eb
, item
);
1036 while (cur
< total
) {
1037 name_len
= btrfs_dir_name_len(eb
, di
);
1038 data_len
= btrfs_dir_data_len(eb
, di
);
1039 type
= btrfs_dir_type(eb
, di
);
1040 btrfs_dir_item_key_to_cpu(eb
, di
, &di_key
);
1042 if (type
== BTRFS_FT_XATTR
) {
1043 if (name_len
> XATTR_NAME_MAX
) {
1044 ret
= -ENAMETOOLONG
;
1047 if (name_len
+ data_len
>
1048 BTRFS_MAX_XATTR_SIZE(root
->fs_info
)) {
1056 if (name_len
+ data_len
> PATH_MAX
) {
1057 ret
= -ENAMETOOLONG
;
1062 if (name_len
+ data_len
> buf_len
) {
1063 buf_len
= name_len
+ data_len
;
1064 if (is_vmalloc_addr(buf
)) {
1068 char *tmp
= krealloc(buf
, buf_len
,
1069 GFP_KERNEL
| __GFP_NOWARN
);
1076 buf
= kvmalloc(buf_len
, GFP_KERNEL
);
1084 read_extent_buffer(eb
, buf
, (unsigned long)(di
+ 1),
1085 name_len
+ data_len
);
1087 len
= sizeof(*di
) + name_len
+ data_len
;
1088 di
= (struct btrfs_dir_item
*)((char *)di
+ len
);
1091 ret
= iterate(num
, &di_key
, buf
, name_len
, buf
+ name_len
,
1092 data_len
, type
, ctx
);
1108 static int __copy_first_ref(int num
, u64 dir
, int index
,
1109 struct fs_path
*p
, void *ctx
)
1112 struct fs_path
*pt
= ctx
;
1114 ret
= fs_path_copy(pt
, p
);
1118 /* we want the first only */
1123 * Retrieve the first path of an inode. If an inode has more then one
1124 * ref/hardlink, this is ignored.
1126 static int get_inode_path(struct btrfs_root
*root
,
1127 u64 ino
, struct fs_path
*path
)
1130 struct btrfs_key key
, found_key
;
1131 struct btrfs_path
*p
;
1133 p
= alloc_path_for_send();
1137 fs_path_reset(path
);
1140 key
.type
= BTRFS_INODE_REF_KEY
;
1143 ret
= btrfs_search_slot_for_read(root
, &key
, p
, 1, 0);
1150 btrfs_item_key_to_cpu(p
->nodes
[0], &found_key
, p
->slots
[0]);
1151 if (found_key
.objectid
!= ino
||
1152 (found_key
.type
!= BTRFS_INODE_REF_KEY
&&
1153 found_key
.type
!= BTRFS_INODE_EXTREF_KEY
)) {
1158 ret
= iterate_inode_ref(root
, p
, &found_key
, 1,
1159 __copy_first_ref
, path
);
1169 struct backref_ctx
{
1170 struct send_ctx
*sctx
;
1172 struct btrfs_path
*path
;
1173 /* number of total found references */
1177 * used for clones found in send_root. clones found behind cur_objectid
1178 * and cur_offset are not considered as allowed clones.
1183 /* may be truncated in case it's the last extent in a file */
1186 /* data offset in the file extent item */
1189 /* Just to check for bugs in backref resolving */
1193 static int __clone_root_cmp_bsearch(const void *key
, const void *elt
)
1195 u64 root
= (u64
)(uintptr_t)key
;
1196 struct clone_root
*cr
= (struct clone_root
*)elt
;
1198 if (root
< cr
->root
->objectid
)
1200 if (root
> cr
->root
->objectid
)
1205 static int __clone_root_cmp_sort(const void *e1
, const void *e2
)
1207 struct clone_root
*cr1
= (struct clone_root
*)e1
;
1208 struct clone_root
*cr2
= (struct clone_root
*)e2
;
1210 if (cr1
->root
->objectid
< cr2
->root
->objectid
)
1212 if (cr1
->root
->objectid
> cr2
->root
->objectid
)
1218 * Called for every backref that is found for the current extent.
1219 * Results are collected in sctx->clone_roots->ino/offset/found_refs
1221 static int __iterate_backrefs(u64 ino
, u64 offset
, u64 root
, void *ctx_
)
1223 struct backref_ctx
*bctx
= ctx_
;
1224 struct clone_root
*found
;
1228 /* First check if the root is in the list of accepted clone sources */
1229 found
= bsearch((void *)(uintptr_t)root
, bctx
->sctx
->clone_roots
,
1230 bctx
->sctx
->clone_roots_cnt
,
1231 sizeof(struct clone_root
),
1232 __clone_root_cmp_bsearch
);
1236 if (found
->root
== bctx
->sctx
->send_root
&&
1237 ino
== bctx
->cur_objectid
&&
1238 offset
== bctx
->cur_offset
) {
1239 bctx
->found_itself
= 1;
1243 * There are inodes that have extents that lie behind its i_size. Don't
1244 * accept clones from these extents.
1246 ret
= __get_inode_info(found
->root
, bctx
->path
, ino
, &i_size
, NULL
, NULL
,
1248 btrfs_release_path(bctx
->path
);
1252 if (offset
+ bctx
->data_offset
+ bctx
->extent_len
> i_size
)
1256 * Make sure we don't consider clones from send_root that are
1257 * behind the current inode/offset.
1259 if (found
->root
== bctx
->sctx
->send_root
) {
1261 * TODO for the moment we don't accept clones from the inode
1262 * that is currently send. We may change this when
1263 * BTRFS_IOC_CLONE_RANGE supports cloning from and to the same
1266 if (ino
>= bctx
->cur_objectid
)
1271 found
->found_refs
++;
1272 if (ino
< found
->ino
) {
1274 found
->offset
= offset
;
1275 } else if (found
->ino
== ino
) {
1277 * same extent found more then once in the same file.
1279 if (found
->offset
> offset
+ bctx
->extent_len
)
1280 found
->offset
= offset
;
1287 * Given an inode, offset and extent item, it finds a good clone for a clone
1288 * instruction. Returns -ENOENT when none could be found. The function makes
1289 * sure that the returned clone is usable at the point where sending is at the
1290 * moment. This means, that no clones are accepted which lie behind the current
1293 * path must point to the extent item when called.
1295 static int find_extent_clone(struct send_ctx
*sctx
,
1296 struct btrfs_path
*path
,
1297 u64 ino
, u64 data_offset
,
1299 struct clone_root
**found
)
1301 struct btrfs_fs_info
*fs_info
= sctx
->send_root
->fs_info
;
1307 u64 extent_item_pos
;
1309 struct btrfs_file_extent_item
*fi
;
1310 struct extent_buffer
*eb
= path
->nodes
[0];
1311 struct backref_ctx
*backref_ctx
= NULL
;
1312 struct clone_root
*cur_clone_root
;
1313 struct btrfs_key found_key
;
1314 struct btrfs_path
*tmp_path
;
1318 tmp_path
= alloc_path_for_send();
1322 /* We only use this path under the commit sem */
1323 tmp_path
->need_commit_sem
= 0;
1325 backref_ctx
= kmalloc(sizeof(*backref_ctx
), GFP_KERNEL
);
1331 backref_ctx
->path
= tmp_path
;
1333 if (data_offset
>= ino_size
) {
1335 * There may be extents that lie behind the file's size.
1336 * I at least had this in combination with snapshotting while
1337 * writing large files.
1343 fi
= btrfs_item_ptr(eb
, path
->slots
[0],
1344 struct btrfs_file_extent_item
);
1345 extent_type
= btrfs_file_extent_type(eb
, fi
);
1346 if (extent_type
== BTRFS_FILE_EXTENT_INLINE
) {
1350 compressed
= btrfs_file_extent_compression(eb
, fi
);
1352 num_bytes
= btrfs_file_extent_num_bytes(eb
, fi
);
1353 disk_byte
= btrfs_file_extent_disk_bytenr(eb
, fi
);
1354 if (disk_byte
== 0) {
1358 logical
= disk_byte
+ btrfs_file_extent_offset(eb
, fi
);
1360 down_read(&fs_info
->commit_root_sem
);
1361 ret
= extent_from_logical(fs_info
, disk_byte
, tmp_path
,
1362 &found_key
, &flags
);
1363 up_read(&fs_info
->commit_root_sem
);
1364 btrfs_release_path(tmp_path
);
1368 if (flags
& BTRFS_EXTENT_FLAG_TREE_BLOCK
) {
1374 * Setup the clone roots.
1376 for (i
= 0; i
< sctx
->clone_roots_cnt
; i
++) {
1377 cur_clone_root
= sctx
->clone_roots
+ i
;
1378 cur_clone_root
->ino
= (u64
)-1;
1379 cur_clone_root
->offset
= 0;
1380 cur_clone_root
->found_refs
= 0;
1383 backref_ctx
->sctx
= sctx
;
1384 backref_ctx
->found
= 0;
1385 backref_ctx
->cur_objectid
= ino
;
1386 backref_ctx
->cur_offset
= data_offset
;
1387 backref_ctx
->found_itself
= 0;
1388 backref_ctx
->extent_len
= num_bytes
;
1390 * For non-compressed extents iterate_extent_inodes() gives us extent
1391 * offsets that already take into account the data offset, but not for
1392 * compressed extents, since the offset is logical and not relative to
1393 * the physical extent locations. We must take this into account to
1394 * avoid sending clone offsets that go beyond the source file's size,
1395 * which would result in the clone ioctl failing with -EINVAL on the
1398 if (compressed
== BTRFS_COMPRESS_NONE
)
1399 backref_ctx
->data_offset
= 0;
1401 backref_ctx
->data_offset
= btrfs_file_extent_offset(eb
, fi
);
1404 * The last extent of a file may be too large due to page alignment.
1405 * We need to adjust extent_len in this case so that the checks in
1406 * __iterate_backrefs work.
1408 if (data_offset
+ num_bytes
>= ino_size
)
1409 backref_ctx
->extent_len
= ino_size
- data_offset
;
1412 * Now collect all backrefs.
1414 if (compressed
== BTRFS_COMPRESS_NONE
)
1415 extent_item_pos
= logical
- found_key
.objectid
;
1417 extent_item_pos
= 0;
1418 ret
= iterate_extent_inodes(fs_info
, found_key
.objectid
,
1419 extent_item_pos
, 1, __iterate_backrefs
,
1420 backref_ctx
, false);
1425 if (!backref_ctx
->found_itself
) {
1426 /* found a bug in backref code? */
1429 "did not find backref in send_root. inode=%llu, offset=%llu, disk_byte=%llu found extent=%llu",
1430 ino
, data_offset
, disk_byte
, found_key
.objectid
);
1434 btrfs_debug(fs_info
,
1435 "find_extent_clone: data_offset=%llu, ino=%llu, num_bytes=%llu, logical=%llu",
1436 data_offset
, ino
, num_bytes
, logical
);
1438 if (!backref_ctx
->found
)
1439 btrfs_debug(fs_info
, "no clones found");
1441 cur_clone_root
= NULL
;
1442 for (i
= 0; i
< sctx
->clone_roots_cnt
; i
++) {
1443 if (sctx
->clone_roots
[i
].found_refs
) {
1444 if (!cur_clone_root
)
1445 cur_clone_root
= sctx
->clone_roots
+ i
;
1446 else if (sctx
->clone_roots
[i
].root
== sctx
->send_root
)
1447 /* prefer clones from send_root over others */
1448 cur_clone_root
= sctx
->clone_roots
+ i
;
1453 if (cur_clone_root
) {
1454 *found
= cur_clone_root
;
1461 btrfs_free_path(tmp_path
);
1466 static int read_symlink(struct btrfs_root
*root
,
1468 struct fs_path
*dest
)
1471 struct btrfs_path
*path
;
1472 struct btrfs_key key
;
1473 struct btrfs_file_extent_item
*ei
;
1479 path
= alloc_path_for_send();
1484 key
.type
= BTRFS_EXTENT_DATA_KEY
;
1486 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
1491 * An empty symlink inode. Can happen in rare error paths when
1492 * creating a symlink (transaction committed before the inode
1493 * eviction handler removed the symlink inode items and a crash
1494 * happened in between or the subvol was snapshoted in between).
1495 * Print an informative message to dmesg/syslog so that the user
1496 * can delete the symlink.
1498 btrfs_err(root
->fs_info
,
1499 "Found empty symlink inode %llu at root %llu",
1500 ino
, root
->root_key
.objectid
);
1505 ei
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
1506 struct btrfs_file_extent_item
);
1507 type
= btrfs_file_extent_type(path
->nodes
[0], ei
);
1508 compression
= btrfs_file_extent_compression(path
->nodes
[0], ei
);
1509 BUG_ON(type
!= BTRFS_FILE_EXTENT_INLINE
);
1510 BUG_ON(compression
);
1512 off
= btrfs_file_extent_inline_start(ei
);
1513 len
= btrfs_file_extent_inline_len(path
->nodes
[0], path
->slots
[0], ei
);
1515 ret
= fs_path_add_from_extent_buffer(dest
, path
->nodes
[0], off
, len
);
1518 btrfs_free_path(path
);
1523 * Helper function to generate a file name that is unique in the root of
1524 * send_root and parent_root. This is used to generate names for orphan inodes.
1526 static int gen_unique_name(struct send_ctx
*sctx
,
1528 struct fs_path
*dest
)
1531 struct btrfs_path
*path
;
1532 struct btrfs_dir_item
*di
;
1537 path
= alloc_path_for_send();
1542 len
= snprintf(tmp
, sizeof(tmp
), "o%llu-%llu-%llu",
1544 ASSERT(len
< sizeof(tmp
));
1546 di
= btrfs_lookup_dir_item(NULL
, sctx
->send_root
,
1547 path
, BTRFS_FIRST_FREE_OBJECTID
,
1548 tmp
, strlen(tmp
), 0);
1549 btrfs_release_path(path
);
1555 /* not unique, try again */
1560 if (!sctx
->parent_root
) {
1566 di
= btrfs_lookup_dir_item(NULL
, sctx
->parent_root
,
1567 path
, BTRFS_FIRST_FREE_OBJECTID
,
1568 tmp
, strlen(tmp
), 0);
1569 btrfs_release_path(path
);
1575 /* not unique, try again */
1583 ret
= fs_path_add(dest
, tmp
, strlen(tmp
));
1586 btrfs_free_path(path
);
1591 inode_state_no_change
,
1592 inode_state_will_create
,
1593 inode_state_did_create
,
1594 inode_state_will_delete
,
1595 inode_state_did_delete
,
1598 static int get_cur_inode_state(struct send_ctx
*sctx
, u64 ino
, u64 gen
)
1606 ret
= get_inode_info(sctx
->send_root
, ino
, NULL
, &left_gen
, NULL
, NULL
,
1608 if (ret
< 0 && ret
!= -ENOENT
)
1612 if (!sctx
->parent_root
) {
1613 right_ret
= -ENOENT
;
1615 ret
= get_inode_info(sctx
->parent_root
, ino
, NULL
, &right_gen
,
1616 NULL
, NULL
, NULL
, NULL
);
1617 if (ret
< 0 && ret
!= -ENOENT
)
1622 if (!left_ret
&& !right_ret
) {
1623 if (left_gen
== gen
&& right_gen
== gen
) {
1624 ret
= inode_state_no_change
;
1625 } else if (left_gen
== gen
) {
1626 if (ino
< sctx
->send_progress
)
1627 ret
= inode_state_did_create
;
1629 ret
= inode_state_will_create
;
1630 } else if (right_gen
== gen
) {
1631 if (ino
< sctx
->send_progress
)
1632 ret
= inode_state_did_delete
;
1634 ret
= inode_state_will_delete
;
1638 } else if (!left_ret
) {
1639 if (left_gen
== gen
) {
1640 if (ino
< sctx
->send_progress
)
1641 ret
= inode_state_did_create
;
1643 ret
= inode_state_will_create
;
1647 } else if (!right_ret
) {
1648 if (right_gen
== gen
) {
1649 if (ino
< sctx
->send_progress
)
1650 ret
= inode_state_did_delete
;
1652 ret
= inode_state_will_delete
;
1664 static int is_inode_existent(struct send_ctx
*sctx
, u64 ino
, u64 gen
)
1668 if (ino
== BTRFS_FIRST_FREE_OBJECTID
)
1671 ret
= get_cur_inode_state(sctx
, ino
, gen
);
1675 if (ret
== inode_state_no_change
||
1676 ret
== inode_state_did_create
||
1677 ret
== inode_state_will_delete
)
1687 * Helper function to lookup a dir item in a dir.
1689 static int lookup_dir_item_inode(struct btrfs_root
*root
,
1690 u64 dir
, const char *name
, int name_len
,
1695 struct btrfs_dir_item
*di
;
1696 struct btrfs_key key
;
1697 struct btrfs_path
*path
;
1699 path
= alloc_path_for_send();
1703 di
= btrfs_lookup_dir_item(NULL
, root
, path
,
1704 dir
, name
, name_len
, 0);
1713 btrfs_dir_item_key_to_cpu(path
->nodes
[0], di
, &key
);
1714 if (key
.type
== BTRFS_ROOT_ITEM_KEY
) {
1718 *found_inode
= key
.objectid
;
1719 *found_type
= btrfs_dir_type(path
->nodes
[0], di
);
1722 btrfs_free_path(path
);
1727 * Looks up the first btrfs_inode_ref of a given ino. It returns the parent dir,
1728 * generation of the parent dir and the name of the dir entry.
1730 static int get_first_ref(struct btrfs_root
*root
, u64 ino
,
1731 u64
*dir
, u64
*dir_gen
, struct fs_path
*name
)
1734 struct btrfs_key key
;
1735 struct btrfs_key found_key
;
1736 struct btrfs_path
*path
;
1740 path
= alloc_path_for_send();
1745 key
.type
= BTRFS_INODE_REF_KEY
;
1748 ret
= btrfs_search_slot_for_read(root
, &key
, path
, 1, 0);
1752 btrfs_item_key_to_cpu(path
->nodes
[0], &found_key
,
1754 if (ret
|| found_key
.objectid
!= ino
||
1755 (found_key
.type
!= BTRFS_INODE_REF_KEY
&&
1756 found_key
.type
!= BTRFS_INODE_EXTREF_KEY
)) {
1761 if (found_key
.type
== BTRFS_INODE_REF_KEY
) {
1762 struct btrfs_inode_ref
*iref
;
1763 iref
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
1764 struct btrfs_inode_ref
);
1765 len
= btrfs_inode_ref_name_len(path
->nodes
[0], iref
);
1766 ret
= fs_path_add_from_extent_buffer(name
, path
->nodes
[0],
1767 (unsigned long)(iref
+ 1),
1769 parent_dir
= found_key
.offset
;
1771 struct btrfs_inode_extref
*extref
;
1772 extref
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
1773 struct btrfs_inode_extref
);
1774 len
= btrfs_inode_extref_name_len(path
->nodes
[0], extref
);
1775 ret
= fs_path_add_from_extent_buffer(name
, path
->nodes
[0],
1776 (unsigned long)&extref
->name
, len
);
1777 parent_dir
= btrfs_inode_extref_parent(path
->nodes
[0], extref
);
1781 btrfs_release_path(path
);
1784 ret
= get_inode_info(root
, parent_dir
, NULL
, dir_gen
, NULL
,
1793 btrfs_free_path(path
);
1797 static int is_first_ref(struct btrfs_root
*root
,
1799 const char *name
, int name_len
)
1802 struct fs_path
*tmp_name
;
1805 tmp_name
= fs_path_alloc();
1809 ret
= get_first_ref(root
, ino
, &tmp_dir
, NULL
, tmp_name
);
1813 if (dir
!= tmp_dir
|| name_len
!= fs_path_len(tmp_name
)) {
1818 ret
= !memcmp(tmp_name
->start
, name
, name_len
);
1821 fs_path_free(tmp_name
);
1826 * Used by process_recorded_refs to determine if a new ref would overwrite an
1827 * already existing ref. In case it detects an overwrite, it returns the
1828 * inode/gen in who_ino/who_gen.
1829 * When an overwrite is detected, process_recorded_refs does proper orphanizing
1830 * to make sure later references to the overwritten inode are possible.
1831 * Orphanizing is however only required for the first ref of an inode.
1832 * process_recorded_refs does an additional is_first_ref check to see if
1833 * orphanizing is really required.
1835 static int will_overwrite_ref(struct send_ctx
*sctx
, u64 dir
, u64 dir_gen
,
1836 const char *name
, int name_len
,
1837 u64
*who_ino
, u64
*who_gen
, u64
*who_mode
)
1841 u64 other_inode
= 0;
1844 if (!sctx
->parent_root
)
1847 ret
= is_inode_existent(sctx
, dir
, dir_gen
);
1852 * If we have a parent root we need to verify that the parent dir was
1853 * not deleted and then re-created, if it was then we have no overwrite
1854 * and we can just unlink this entry.
1856 if (sctx
->parent_root
&& dir
!= BTRFS_FIRST_FREE_OBJECTID
) {
1857 ret
= get_inode_info(sctx
->parent_root
, dir
, NULL
, &gen
, NULL
,
1859 if (ret
< 0 && ret
!= -ENOENT
)
1869 ret
= lookup_dir_item_inode(sctx
->parent_root
, dir
, name
, name_len
,
1870 &other_inode
, &other_type
);
1871 if (ret
< 0 && ret
!= -ENOENT
)
1879 * Check if the overwritten ref was already processed. If yes, the ref
1880 * was already unlinked/moved, so we can safely assume that we will not
1881 * overwrite anything at this point in time.
1883 if (other_inode
> sctx
->send_progress
||
1884 is_waiting_for_move(sctx
, other_inode
)) {
1885 ret
= get_inode_info(sctx
->parent_root
, other_inode
, NULL
,
1886 who_gen
, who_mode
, NULL
, NULL
, NULL
);
1891 *who_ino
= other_inode
;
1901 * Checks if the ref was overwritten by an already processed inode. This is
1902 * used by __get_cur_name_and_parent to find out if the ref was orphanized and
1903 * thus the orphan name needs be used.
1904 * process_recorded_refs also uses it to avoid unlinking of refs that were
1907 static int did_overwrite_ref(struct send_ctx
*sctx
,
1908 u64 dir
, u64 dir_gen
,
1909 u64 ino
, u64 ino_gen
,
1910 const char *name
, int name_len
)
1917 if (!sctx
->parent_root
)
1920 ret
= is_inode_existent(sctx
, dir
, dir_gen
);
1924 if (dir
!= BTRFS_FIRST_FREE_OBJECTID
) {
1925 ret
= get_inode_info(sctx
->send_root
, dir
, NULL
, &gen
, NULL
,
1927 if (ret
< 0 && ret
!= -ENOENT
)
1937 /* check if the ref was overwritten by another ref */
1938 ret
= lookup_dir_item_inode(sctx
->send_root
, dir
, name
, name_len
,
1939 &ow_inode
, &other_type
);
1940 if (ret
< 0 && ret
!= -ENOENT
)
1943 /* was never and will never be overwritten */
1948 ret
= get_inode_info(sctx
->send_root
, ow_inode
, NULL
, &gen
, NULL
, NULL
,
1953 if (ow_inode
== ino
&& gen
== ino_gen
) {
1959 * We know that it is or will be overwritten. Check this now.
1960 * The current inode being processed might have been the one that caused
1961 * inode 'ino' to be orphanized, therefore check if ow_inode matches
1962 * the current inode being processed.
1964 if ((ow_inode
< sctx
->send_progress
) ||
1965 (ino
!= sctx
->cur_ino
&& ow_inode
== sctx
->cur_ino
&&
1966 gen
== sctx
->cur_inode_gen
))
1976 * Same as did_overwrite_ref, but also checks if it is the first ref of an inode
1977 * that got overwritten. This is used by process_recorded_refs to determine
1978 * if it has to use the path as returned by get_cur_path or the orphan name.
1980 static int did_overwrite_first_ref(struct send_ctx
*sctx
, u64 ino
, u64 gen
)
1983 struct fs_path
*name
= NULL
;
1987 if (!sctx
->parent_root
)
1990 name
= fs_path_alloc();
1994 ret
= get_first_ref(sctx
->parent_root
, ino
, &dir
, &dir_gen
, name
);
1998 ret
= did_overwrite_ref(sctx
, dir
, dir_gen
, ino
, gen
,
1999 name
->start
, fs_path_len(name
));
2007 * Insert a name cache entry. On 32bit kernels the radix tree index is 32bit,
2008 * so we need to do some special handling in case we have clashes. This function
2009 * takes care of this with the help of name_cache_entry::radix_list.
2010 * In case of error, nce is kfreed.
2012 static int name_cache_insert(struct send_ctx
*sctx
,
2013 struct name_cache_entry
*nce
)
2016 struct list_head
*nce_head
;
2018 nce_head
= radix_tree_lookup(&sctx
->name_cache
,
2019 (unsigned long)nce
->ino
);
2021 nce_head
= kmalloc(sizeof(*nce_head
), GFP_KERNEL
);
2026 INIT_LIST_HEAD(nce_head
);
2028 ret
= radix_tree_insert(&sctx
->name_cache
, nce
->ino
, nce_head
);
2035 list_add_tail(&nce
->radix_list
, nce_head
);
2036 list_add_tail(&nce
->list
, &sctx
->name_cache_list
);
2037 sctx
->name_cache_size
++;
2042 static void name_cache_delete(struct send_ctx
*sctx
,
2043 struct name_cache_entry
*nce
)
2045 struct list_head
*nce_head
;
2047 nce_head
= radix_tree_lookup(&sctx
->name_cache
,
2048 (unsigned long)nce
->ino
);
2050 btrfs_err(sctx
->send_root
->fs_info
,
2051 "name_cache_delete lookup failed ino %llu cache size %d, leaking memory",
2052 nce
->ino
, sctx
->name_cache_size
);
2055 list_del(&nce
->radix_list
);
2056 list_del(&nce
->list
);
2057 sctx
->name_cache_size
--;
2060 * We may not get to the final release of nce_head if the lookup fails
2062 if (nce_head
&& list_empty(nce_head
)) {
2063 radix_tree_delete(&sctx
->name_cache
, (unsigned long)nce
->ino
);
2068 static struct name_cache_entry
*name_cache_search(struct send_ctx
*sctx
,
2071 struct list_head
*nce_head
;
2072 struct name_cache_entry
*cur
;
2074 nce_head
= radix_tree_lookup(&sctx
->name_cache
, (unsigned long)ino
);
2078 list_for_each_entry(cur
, nce_head
, radix_list
) {
2079 if (cur
->ino
== ino
&& cur
->gen
== gen
)
2086 * Removes the entry from the list and adds it back to the end. This marks the
2087 * entry as recently used so that name_cache_clean_unused does not remove it.
2089 static void name_cache_used(struct send_ctx
*sctx
, struct name_cache_entry
*nce
)
2091 list_del(&nce
->list
);
2092 list_add_tail(&nce
->list
, &sctx
->name_cache_list
);
2096 * Remove some entries from the beginning of name_cache_list.
2098 static void name_cache_clean_unused(struct send_ctx
*sctx
)
2100 struct name_cache_entry
*nce
;
2102 if (sctx
->name_cache_size
< SEND_CTX_NAME_CACHE_CLEAN_SIZE
)
2105 while (sctx
->name_cache_size
> SEND_CTX_MAX_NAME_CACHE_SIZE
) {
2106 nce
= list_entry(sctx
->name_cache_list
.next
,
2107 struct name_cache_entry
, list
);
2108 name_cache_delete(sctx
, nce
);
2113 static void name_cache_free(struct send_ctx
*sctx
)
2115 struct name_cache_entry
*nce
;
2117 while (!list_empty(&sctx
->name_cache_list
)) {
2118 nce
= list_entry(sctx
->name_cache_list
.next
,
2119 struct name_cache_entry
, list
);
2120 name_cache_delete(sctx
, nce
);
2126 * Used by get_cur_path for each ref up to the root.
2127 * Returns 0 if it succeeded.
2128 * Returns 1 if the inode is not existent or got overwritten. In that case, the
2129 * name is an orphan name. This instructs get_cur_path to stop iterating. If 1
2130 * is returned, parent_ino/parent_gen are not guaranteed to be valid.
2131 * Returns <0 in case of error.
2133 static int __get_cur_name_and_parent(struct send_ctx
*sctx
,
2137 struct fs_path
*dest
)
2141 struct name_cache_entry
*nce
= NULL
;
2144 * First check if we already did a call to this function with the same
2145 * ino/gen. If yes, check if the cache entry is still up-to-date. If yes
2146 * return the cached result.
2148 nce
= name_cache_search(sctx
, ino
, gen
);
2150 if (ino
< sctx
->send_progress
&& nce
->need_later_update
) {
2151 name_cache_delete(sctx
, nce
);
2155 name_cache_used(sctx
, nce
);
2156 *parent_ino
= nce
->parent_ino
;
2157 *parent_gen
= nce
->parent_gen
;
2158 ret
= fs_path_add(dest
, nce
->name
, nce
->name_len
);
2167 * If the inode is not existent yet, add the orphan name and return 1.
2168 * This should only happen for the parent dir that we determine in
2171 ret
= is_inode_existent(sctx
, ino
, gen
);
2176 ret
= gen_unique_name(sctx
, ino
, gen
, dest
);
2184 * Depending on whether the inode was already processed or not, use
2185 * send_root or parent_root for ref lookup.
2187 if (ino
< sctx
->send_progress
)
2188 ret
= get_first_ref(sctx
->send_root
, ino
,
2189 parent_ino
, parent_gen
, dest
);
2191 ret
= get_first_ref(sctx
->parent_root
, ino
,
2192 parent_ino
, parent_gen
, dest
);
2197 * Check if the ref was overwritten by an inode's ref that was processed
2198 * earlier. If yes, treat as orphan and return 1.
2200 ret
= did_overwrite_ref(sctx
, *parent_ino
, *parent_gen
, ino
, gen
,
2201 dest
->start
, dest
->end
- dest
->start
);
2205 fs_path_reset(dest
);
2206 ret
= gen_unique_name(sctx
, ino
, gen
, dest
);
2214 * Store the result of the lookup in the name cache.
2216 nce
= kmalloc(sizeof(*nce
) + fs_path_len(dest
) + 1, GFP_KERNEL
);
2224 nce
->parent_ino
= *parent_ino
;
2225 nce
->parent_gen
= *parent_gen
;
2226 nce
->name_len
= fs_path_len(dest
);
2228 strcpy(nce
->name
, dest
->start
);
2230 if (ino
< sctx
->send_progress
)
2231 nce
->need_later_update
= 0;
2233 nce
->need_later_update
= 1;
2235 nce_ret
= name_cache_insert(sctx
, nce
);
2238 name_cache_clean_unused(sctx
);
2245 * Magic happens here. This function returns the first ref to an inode as it
2246 * would look like while receiving the stream at this point in time.
2247 * We walk the path up to the root. For every inode in between, we check if it
2248 * was already processed/sent. If yes, we continue with the parent as found
2249 * in send_root. If not, we continue with the parent as found in parent_root.
2250 * If we encounter an inode that was deleted at this point in time, we use the
2251 * inodes "orphan" name instead of the real name and stop. Same with new inodes
2252 * that were not created yet and overwritten inodes/refs.
2254 * When do we have have orphan inodes:
2255 * 1. When an inode is freshly created and thus no valid refs are available yet
2256 * 2. When a directory lost all it's refs (deleted) but still has dir items
2257 * inside which were not processed yet (pending for move/delete). If anyone
2258 * tried to get the path to the dir items, it would get a path inside that
2260 * 3. When an inode is moved around or gets new links, it may overwrite the ref
2261 * of an unprocessed inode. If in that case the first ref would be
2262 * overwritten, the overwritten inode gets "orphanized". Later when we
2263 * process this overwritten inode, it is restored at a new place by moving
2266 * sctx->send_progress tells this function at which point in time receiving
2269 static int get_cur_path(struct send_ctx
*sctx
, u64 ino
, u64 gen
,
2270 struct fs_path
*dest
)
2273 struct fs_path
*name
= NULL
;
2274 u64 parent_inode
= 0;
2278 name
= fs_path_alloc();
2285 fs_path_reset(dest
);
2287 while (!stop
&& ino
!= BTRFS_FIRST_FREE_OBJECTID
) {
2288 struct waiting_dir_move
*wdm
;
2290 fs_path_reset(name
);
2292 if (is_waiting_for_rm(sctx
, ino
)) {
2293 ret
= gen_unique_name(sctx
, ino
, gen
, name
);
2296 ret
= fs_path_add_path(dest
, name
);
2300 wdm
= get_waiting_dir_move(sctx
, ino
);
2301 if (wdm
&& wdm
->orphanized
) {
2302 ret
= gen_unique_name(sctx
, ino
, gen
, name
);
2305 ret
= get_first_ref(sctx
->parent_root
, ino
,
2306 &parent_inode
, &parent_gen
, name
);
2308 ret
= __get_cur_name_and_parent(sctx
, ino
, gen
,
2318 ret
= fs_path_add_path(dest
, name
);
2329 fs_path_unreverse(dest
);
2334 * Sends a BTRFS_SEND_C_SUBVOL command/item to userspace
2336 static int send_subvol_begin(struct send_ctx
*sctx
)
2339 struct btrfs_root
*send_root
= sctx
->send_root
;
2340 struct btrfs_root
*parent_root
= sctx
->parent_root
;
2341 struct btrfs_path
*path
;
2342 struct btrfs_key key
;
2343 struct btrfs_root_ref
*ref
;
2344 struct extent_buffer
*leaf
;
2348 path
= btrfs_alloc_path();
2352 name
= kmalloc(BTRFS_PATH_NAME_MAX
, GFP_KERNEL
);
2354 btrfs_free_path(path
);
2358 key
.objectid
= send_root
->objectid
;
2359 key
.type
= BTRFS_ROOT_BACKREF_KEY
;
2362 ret
= btrfs_search_slot_for_read(send_root
->fs_info
->tree_root
,
2371 leaf
= path
->nodes
[0];
2372 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
2373 if (key
.type
!= BTRFS_ROOT_BACKREF_KEY
||
2374 key
.objectid
!= send_root
->objectid
) {
2378 ref
= btrfs_item_ptr(leaf
, path
->slots
[0], struct btrfs_root_ref
);
2379 namelen
= btrfs_root_ref_name_len(leaf
, ref
);
2380 read_extent_buffer(leaf
, name
, (unsigned long)(ref
+ 1), namelen
);
2381 btrfs_release_path(path
);
2384 ret
= begin_cmd(sctx
, BTRFS_SEND_C_SNAPSHOT
);
2388 ret
= begin_cmd(sctx
, BTRFS_SEND_C_SUBVOL
);
2393 TLV_PUT_STRING(sctx
, BTRFS_SEND_A_PATH
, name
, namelen
);
2395 if (!btrfs_is_empty_uuid(sctx
->send_root
->root_item
.received_uuid
))
2396 TLV_PUT_UUID(sctx
, BTRFS_SEND_A_UUID
,
2397 sctx
->send_root
->root_item
.received_uuid
);
2399 TLV_PUT_UUID(sctx
, BTRFS_SEND_A_UUID
,
2400 sctx
->send_root
->root_item
.uuid
);
2402 TLV_PUT_U64(sctx
, BTRFS_SEND_A_CTRANSID
,
2403 le64_to_cpu(sctx
->send_root
->root_item
.ctransid
));
2405 if (!btrfs_is_empty_uuid(parent_root
->root_item
.received_uuid
))
2406 TLV_PUT_UUID(sctx
, BTRFS_SEND_A_CLONE_UUID
,
2407 parent_root
->root_item
.received_uuid
);
2409 TLV_PUT_UUID(sctx
, BTRFS_SEND_A_CLONE_UUID
,
2410 parent_root
->root_item
.uuid
);
2411 TLV_PUT_U64(sctx
, BTRFS_SEND_A_CLONE_CTRANSID
,
2412 le64_to_cpu(sctx
->parent_root
->root_item
.ctransid
));
2415 ret
= send_cmd(sctx
);
2419 btrfs_free_path(path
);
2424 static int send_truncate(struct send_ctx
*sctx
, u64 ino
, u64 gen
, u64 size
)
2426 struct btrfs_fs_info
*fs_info
= sctx
->send_root
->fs_info
;
2430 btrfs_debug(fs_info
, "send_truncate %llu size=%llu", ino
, size
);
2432 p
= fs_path_alloc();
2436 ret
= begin_cmd(sctx
, BTRFS_SEND_C_TRUNCATE
);
2440 ret
= get_cur_path(sctx
, ino
, gen
, p
);
2443 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, p
);
2444 TLV_PUT_U64(sctx
, BTRFS_SEND_A_SIZE
, size
);
2446 ret
= send_cmd(sctx
);
2454 static int send_chmod(struct send_ctx
*sctx
, u64 ino
, u64 gen
, u64 mode
)
2456 struct btrfs_fs_info
*fs_info
= sctx
->send_root
->fs_info
;
2460 btrfs_debug(fs_info
, "send_chmod %llu mode=%llu", ino
, mode
);
2462 p
= fs_path_alloc();
2466 ret
= begin_cmd(sctx
, BTRFS_SEND_C_CHMOD
);
2470 ret
= get_cur_path(sctx
, ino
, gen
, p
);
2473 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, p
);
2474 TLV_PUT_U64(sctx
, BTRFS_SEND_A_MODE
, mode
& 07777);
2476 ret
= send_cmd(sctx
);
2484 static int send_chown(struct send_ctx
*sctx
, u64 ino
, u64 gen
, u64 uid
, u64 gid
)
2486 struct btrfs_fs_info
*fs_info
= sctx
->send_root
->fs_info
;
2490 btrfs_debug(fs_info
, "send_chown %llu uid=%llu, gid=%llu",
2493 p
= fs_path_alloc();
2497 ret
= begin_cmd(sctx
, BTRFS_SEND_C_CHOWN
);
2501 ret
= get_cur_path(sctx
, ino
, gen
, p
);
2504 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, p
);
2505 TLV_PUT_U64(sctx
, BTRFS_SEND_A_UID
, uid
);
2506 TLV_PUT_U64(sctx
, BTRFS_SEND_A_GID
, gid
);
2508 ret
= send_cmd(sctx
);
2516 static int send_utimes(struct send_ctx
*sctx
, u64 ino
, u64 gen
)
2518 struct btrfs_fs_info
*fs_info
= sctx
->send_root
->fs_info
;
2520 struct fs_path
*p
= NULL
;
2521 struct btrfs_inode_item
*ii
;
2522 struct btrfs_path
*path
= NULL
;
2523 struct extent_buffer
*eb
;
2524 struct btrfs_key key
;
2527 btrfs_debug(fs_info
, "send_utimes %llu", ino
);
2529 p
= fs_path_alloc();
2533 path
= alloc_path_for_send();
2540 key
.type
= BTRFS_INODE_ITEM_KEY
;
2542 ret
= btrfs_search_slot(NULL
, sctx
->send_root
, &key
, path
, 0, 0);
2548 eb
= path
->nodes
[0];
2549 slot
= path
->slots
[0];
2550 ii
= btrfs_item_ptr(eb
, slot
, struct btrfs_inode_item
);
2552 ret
= begin_cmd(sctx
, BTRFS_SEND_C_UTIMES
);
2556 ret
= get_cur_path(sctx
, ino
, gen
, p
);
2559 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, p
);
2560 TLV_PUT_BTRFS_TIMESPEC(sctx
, BTRFS_SEND_A_ATIME
, eb
, &ii
->atime
);
2561 TLV_PUT_BTRFS_TIMESPEC(sctx
, BTRFS_SEND_A_MTIME
, eb
, &ii
->mtime
);
2562 TLV_PUT_BTRFS_TIMESPEC(sctx
, BTRFS_SEND_A_CTIME
, eb
, &ii
->ctime
);
2563 /* TODO Add otime support when the otime patches get into upstream */
2565 ret
= send_cmd(sctx
);
2570 btrfs_free_path(path
);
2575 * Sends a BTRFS_SEND_C_MKXXX or SYMLINK command to user space. We don't have
2576 * a valid path yet because we did not process the refs yet. So, the inode
2577 * is created as orphan.
2579 static int send_create_inode(struct send_ctx
*sctx
, u64 ino
)
2581 struct btrfs_fs_info
*fs_info
= sctx
->send_root
->fs_info
;
2589 btrfs_debug(fs_info
, "send_create_inode %llu", ino
);
2591 p
= fs_path_alloc();
2595 if (ino
!= sctx
->cur_ino
) {
2596 ret
= get_inode_info(sctx
->send_root
, ino
, NULL
, &gen
, &mode
,
2601 gen
= sctx
->cur_inode_gen
;
2602 mode
= sctx
->cur_inode_mode
;
2603 rdev
= sctx
->cur_inode_rdev
;
2606 if (S_ISREG(mode
)) {
2607 cmd
= BTRFS_SEND_C_MKFILE
;
2608 } else if (S_ISDIR(mode
)) {
2609 cmd
= BTRFS_SEND_C_MKDIR
;
2610 } else if (S_ISLNK(mode
)) {
2611 cmd
= BTRFS_SEND_C_SYMLINK
;
2612 } else if (S_ISCHR(mode
) || S_ISBLK(mode
)) {
2613 cmd
= BTRFS_SEND_C_MKNOD
;
2614 } else if (S_ISFIFO(mode
)) {
2615 cmd
= BTRFS_SEND_C_MKFIFO
;
2616 } else if (S_ISSOCK(mode
)) {
2617 cmd
= BTRFS_SEND_C_MKSOCK
;
2619 btrfs_warn(sctx
->send_root
->fs_info
, "unexpected inode type %o",
2620 (int)(mode
& S_IFMT
));
2625 ret
= begin_cmd(sctx
, cmd
);
2629 ret
= gen_unique_name(sctx
, ino
, gen
, p
);
2633 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, p
);
2634 TLV_PUT_U64(sctx
, BTRFS_SEND_A_INO
, ino
);
2636 if (S_ISLNK(mode
)) {
2638 ret
= read_symlink(sctx
->send_root
, ino
, p
);
2641 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH_LINK
, p
);
2642 } else if (S_ISCHR(mode
) || S_ISBLK(mode
) ||
2643 S_ISFIFO(mode
) || S_ISSOCK(mode
)) {
2644 TLV_PUT_U64(sctx
, BTRFS_SEND_A_RDEV
, new_encode_dev(rdev
));
2645 TLV_PUT_U64(sctx
, BTRFS_SEND_A_MODE
, mode
);
2648 ret
= send_cmd(sctx
);
2660 * We need some special handling for inodes that get processed before the parent
2661 * directory got created. See process_recorded_refs for details.
2662 * This function does the check if we already created the dir out of order.
2664 static int did_create_dir(struct send_ctx
*sctx
, u64 dir
)
2667 struct btrfs_path
*path
= NULL
;
2668 struct btrfs_key key
;
2669 struct btrfs_key found_key
;
2670 struct btrfs_key di_key
;
2671 struct extent_buffer
*eb
;
2672 struct btrfs_dir_item
*di
;
2675 path
= alloc_path_for_send();
2682 key
.type
= BTRFS_DIR_INDEX_KEY
;
2684 ret
= btrfs_search_slot(NULL
, sctx
->send_root
, &key
, path
, 0, 0);
2689 eb
= path
->nodes
[0];
2690 slot
= path
->slots
[0];
2691 if (slot
>= btrfs_header_nritems(eb
)) {
2692 ret
= btrfs_next_leaf(sctx
->send_root
, path
);
2695 } else if (ret
> 0) {
2702 btrfs_item_key_to_cpu(eb
, &found_key
, slot
);
2703 if (found_key
.objectid
!= key
.objectid
||
2704 found_key
.type
!= key
.type
) {
2709 di
= btrfs_item_ptr(eb
, slot
, struct btrfs_dir_item
);
2710 btrfs_dir_item_key_to_cpu(eb
, di
, &di_key
);
2712 if (di_key
.type
!= BTRFS_ROOT_ITEM_KEY
&&
2713 di_key
.objectid
< sctx
->send_progress
) {
2722 btrfs_free_path(path
);
2727 * Only creates the inode if it is:
2728 * 1. Not a directory
2729 * 2. Or a directory which was not created already due to out of order
2730 * directories. See did_create_dir and process_recorded_refs for details.
2732 static int send_create_inode_if_needed(struct send_ctx
*sctx
)
2736 if (S_ISDIR(sctx
->cur_inode_mode
)) {
2737 ret
= did_create_dir(sctx
, sctx
->cur_ino
);
2746 ret
= send_create_inode(sctx
, sctx
->cur_ino
);
2754 struct recorded_ref
{
2755 struct list_head list
;
2757 struct fs_path
*full_path
;
2763 static void set_ref_path(struct recorded_ref
*ref
, struct fs_path
*path
)
2765 ref
->full_path
= path
;
2766 ref
->name
= (char *)kbasename(ref
->full_path
->start
);
2767 ref
->name_len
= ref
->full_path
->end
- ref
->name
;
2771 * We need to process new refs before deleted refs, but compare_tree gives us
2772 * everything mixed. So we first record all refs and later process them.
2773 * This function is a helper to record one ref.
2775 static int __record_ref(struct list_head
*head
, u64 dir
,
2776 u64 dir_gen
, struct fs_path
*path
)
2778 struct recorded_ref
*ref
;
2780 ref
= kmalloc(sizeof(*ref
), GFP_KERNEL
);
2785 ref
->dir_gen
= dir_gen
;
2786 set_ref_path(ref
, path
);
2787 list_add_tail(&ref
->list
, head
);
2791 static int dup_ref(struct recorded_ref
*ref
, struct list_head
*list
)
2793 struct recorded_ref
*new;
2795 new = kmalloc(sizeof(*ref
), GFP_KERNEL
);
2799 new->dir
= ref
->dir
;
2800 new->dir_gen
= ref
->dir_gen
;
2801 new->full_path
= NULL
;
2802 INIT_LIST_HEAD(&new->list
);
2803 list_add_tail(&new->list
, list
);
2807 static void __free_recorded_refs(struct list_head
*head
)
2809 struct recorded_ref
*cur
;
2811 while (!list_empty(head
)) {
2812 cur
= list_entry(head
->next
, struct recorded_ref
, list
);
2813 fs_path_free(cur
->full_path
);
2814 list_del(&cur
->list
);
2819 static void free_recorded_refs(struct send_ctx
*sctx
)
2821 __free_recorded_refs(&sctx
->new_refs
);
2822 __free_recorded_refs(&sctx
->deleted_refs
);
2826 * Renames/moves a file/dir to its orphan name. Used when the first
2827 * ref of an unprocessed inode gets overwritten and for all non empty
2830 static int orphanize_inode(struct send_ctx
*sctx
, u64 ino
, u64 gen
,
2831 struct fs_path
*path
)
2834 struct fs_path
*orphan
;
2836 orphan
= fs_path_alloc();
2840 ret
= gen_unique_name(sctx
, ino
, gen
, orphan
);
2844 ret
= send_rename(sctx
, path
, orphan
);
2847 fs_path_free(orphan
);
2851 static struct orphan_dir_info
*
2852 add_orphan_dir_info(struct send_ctx
*sctx
, u64 dir_ino
)
2854 struct rb_node
**p
= &sctx
->orphan_dirs
.rb_node
;
2855 struct rb_node
*parent
= NULL
;
2856 struct orphan_dir_info
*entry
, *odi
;
2858 odi
= kmalloc(sizeof(*odi
), GFP_KERNEL
);
2860 return ERR_PTR(-ENOMEM
);
2866 entry
= rb_entry(parent
, struct orphan_dir_info
, node
);
2867 if (dir_ino
< entry
->ino
) {
2869 } else if (dir_ino
> entry
->ino
) {
2870 p
= &(*p
)->rb_right
;
2877 rb_link_node(&odi
->node
, parent
, p
);
2878 rb_insert_color(&odi
->node
, &sctx
->orphan_dirs
);
2882 static struct orphan_dir_info
*
2883 get_orphan_dir_info(struct send_ctx
*sctx
, u64 dir_ino
)
2885 struct rb_node
*n
= sctx
->orphan_dirs
.rb_node
;
2886 struct orphan_dir_info
*entry
;
2889 entry
= rb_entry(n
, struct orphan_dir_info
, node
);
2890 if (dir_ino
< entry
->ino
)
2892 else if (dir_ino
> entry
->ino
)
2900 static int is_waiting_for_rm(struct send_ctx
*sctx
, u64 dir_ino
)
2902 struct orphan_dir_info
*odi
= get_orphan_dir_info(sctx
, dir_ino
);
2907 static void free_orphan_dir_info(struct send_ctx
*sctx
,
2908 struct orphan_dir_info
*odi
)
2912 rb_erase(&odi
->node
, &sctx
->orphan_dirs
);
2917 * Returns 1 if a directory can be removed at this point in time.
2918 * We check this by iterating all dir items and checking if the inode behind
2919 * the dir item was already processed.
2921 static int can_rmdir(struct send_ctx
*sctx
, u64 dir
, u64 dir_gen
,
2925 struct btrfs_root
*root
= sctx
->parent_root
;
2926 struct btrfs_path
*path
;
2927 struct btrfs_key key
;
2928 struct btrfs_key found_key
;
2929 struct btrfs_key loc
;
2930 struct btrfs_dir_item
*di
;
2933 * Don't try to rmdir the top/root subvolume dir.
2935 if (dir
== BTRFS_FIRST_FREE_OBJECTID
)
2938 path
= alloc_path_for_send();
2943 key
.type
= BTRFS_DIR_INDEX_KEY
;
2945 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
2950 struct waiting_dir_move
*dm
;
2952 if (path
->slots
[0] >= btrfs_header_nritems(path
->nodes
[0])) {
2953 ret
= btrfs_next_leaf(root
, path
);
2960 btrfs_item_key_to_cpu(path
->nodes
[0], &found_key
,
2962 if (found_key
.objectid
!= key
.objectid
||
2963 found_key
.type
!= key
.type
)
2966 di
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
2967 struct btrfs_dir_item
);
2968 btrfs_dir_item_key_to_cpu(path
->nodes
[0], di
, &loc
);
2970 dm
= get_waiting_dir_move(sctx
, loc
.objectid
);
2972 struct orphan_dir_info
*odi
;
2974 odi
= add_orphan_dir_info(sctx
, dir
);
2980 dm
->rmdir_ino
= dir
;
2985 if (loc
.objectid
> send_progress
) {
2986 struct orphan_dir_info
*odi
;
2988 odi
= get_orphan_dir_info(sctx
, dir
);
2989 free_orphan_dir_info(sctx
, odi
);
3000 btrfs_free_path(path
);
3004 static int is_waiting_for_move(struct send_ctx
*sctx
, u64 ino
)
3006 struct waiting_dir_move
*entry
= get_waiting_dir_move(sctx
, ino
);
3008 return entry
!= NULL
;
3011 static int add_waiting_dir_move(struct send_ctx
*sctx
, u64 ino
, bool orphanized
)
3013 struct rb_node
**p
= &sctx
->waiting_dir_moves
.rb_node
;
3014 struct rb_node
*parent
= NULL
;
3015 struct waiting_dir_move
*entry
, *dm
;
3017 dm
= kmalloc(sizeof(*dm
), GFP_KERNEL
);
3022 dm
->orphanized
= orphanized
;
3026 entry
= rb_entry(parent
, struct waiting_dir_move
, node
);
3027 if (ino
< entry
->ino
) {
3029 } else if (ino
> entry
->ino
) {
3030 p
= &(*p
)->rb_right
;
3037 rb_link_node(&dm
->node
, parent
, p
);
3038 rb_insert_color(&dm
->node
, &sctx
->waiting_dir_moves
);
3042 static struct waiting_dir_move
*
3043 get_waiting_dir_move(struct send_ctx
*sctx
, u64 ino
)
3045 struct rb_node
*n
= sctx
->waiting_dir_moves
.rb_node
;
3046 struct waiting_dir_move
*entry
;
3049 entry
= rb_entry(n
, struct waiting_dir_move
, node
);
3050 if (ino
< entry
->ino
)
3052 else if (ino
> entry
->ino
)
3060 static void free_waiting_dir_move(struct send_ctx
*sctx
,
3061 struct waiting_dir_move
*dm
)
3065 rb_erase(&dm
->node
, &sctx
->waiting_dir_moves
);
3069 static int add_pending_dir_move(struct send_ctx
*sctx
,
3073 struct list_head
*new_refs
,
3074 struct list_head
*deleted_refs
,
3075 const bool is_orphan
)
3077 struct rb_node
**p
= &sctx
->pending_dir_moves
.rb_node
;
3078 struct rb_node
*parent
= NULL
;
3079 struct pending_dir_move
*entry
= NULL
, *pm
;
3080 struct recorded_ref
*cur
;
3084 pm
= kmalloc(sizeof(*pm
), GFP_KERNEL
);
3087 pm
->parent_ino
= parent_ino
;
3090 INIT_LIST_HEAD(&pm
->list
);
3091 INIT_LIST_HEAD(&pm
->update_refs
);
3092 RB_CLEAR_NODE(&pm
->node
);
3096 entry
= rb_entry(parent
, struct pending_dir_move
, node
);
3097 if (parent_ino
< entry
->parent_ino
) {
3099 } else if (parent_ino
> entry
->parent_ino
) {
3100 p
= &(*p
)->rb_right
;
3107 list_for_each_entry(cur
, deleted_refs
, list
) {
3108 ret
= dup_ref(cur
, &pm
->update_refs
);
3112 list_for_each_entry(cur
, new_refs
, list
) {
3113 ret
= dup_ref(cur
, &pm
->update_refs
);
3118 ret
= add_waiting_dir_move(sctx
, pm
->ino
, is_orphan
);
3123 list_add_tail(&pm
->list
, &entry
->list
);
3125 rb_link_node(&pm
->node
, parent
, p
);
3126 rb_insert_color(&pm
->node
, &sctx
->pending_dir_moves
);
3131 __free_recorded_refs(&pm
->update_refs
);
3137 static struct pending_dir_move
*get_pending_dir_moves(struct send_ctx
*sctx
,
3140 struct rb_node
*n
= sctx
->pending_dir_moves
.rb_node
;
3141 struct pending_dir_move
*entry
;
3144 entry
= rb_entry(n
, struct pending_dir_move
, node
);
3145 if (parent_ino
< entry
->parent_ino
)
3147 else if (parent_ino
> entry
->parent_ino
)
3155 static int path_loop(struct send_ctx
*sctx
, struct fs_path
*name
,
3156 u64 ino
, u64 gen
, u64
*ancestor_ino
)
3159 u64 parent_inode
= 0;
3161 u64 start_ino
= ino
;
3164 while (ino
!= BTRFS_FIRST_FREE_OBJECTID
) {
3165 fs_path_reset(name
);
3167 if (is_waiting_for_rm(sctx
, ino
))
3169 if (is_waiting_for_move(sctx
, ino
)) {
3170 if (*ancestor_ino
== 0)
3171 *ancestor_ino
= ino
;
3172 ret
= get_first_ref(sctx
->parent_root
, ino
,
3173 &parent_inode
, &parent_gen
, name
);
3175 ret
= __get_cur_name_and_parent(sctx
, ino
, gen
,
3185 if (parent_inode
== start_ino
) {
3187 if (*ancestor_ino
== 0)
3188 *ancestor_ino
= ino
;
3197 static int apply_dir_move(struct send_ctx
*sctx
, struct pending_dir_move
*pm
)
3199 struct fs_path
*from_path
= NULL
;
3200 struct fs_path
*to_path
= NULL
;
3201 struct fs_path
*name
= NULL
;
3202 u64 orig_progress
= sctx
->send_progress
;
3203 struct recorded_ref
*cur
;
3204 u64 parent_ino
, parent_gen
;
3205 struct waiting_dir_move
*dm
= NULL
;
3211 name
= fs_path_alloc();
3212 from_path
= fs_path_alloc();
3213 if (!name
|| !from_path
) {
3218 dm
= get_waiting_dir_move(sctx
, pm
->ino
);
3220 rmdir_ino
= dm
->rmdir_ino
;
3221 is_orphan
= dm
->orphanized
;
3222 free_waiting_dir_move(sctx
, dm
);
3225 ret
= gen_unique_name(sctx
, pm
->ino
,
3226 pm
->gen
, from_path
);
3228 ret
= get_first_ref(sctx
->parent_root
, pm
->ino
,
3229 &parent_ino
, &parent_gen
, name
);
3232 ret
= get_cur_path(sctx
, parent_ino
, parent_gen
,
3236 ret
= fs_path_add_path(from_path
, name
);
3241 sctx
->send_progress
= sctx
->cur_ino
+ 1;
3242 ret
= path_loop(sctx
, name
, pm
->ino
, pm
->gen
, &ancestor
);
3246 LIST_HEAD(deleted_refs
);
3247 ASSERT(ancestor
> BTRFS_FIRST_FREE_OBJECTID
);
3248 ret
= add_pending_dir_move(sctx
, pm
->ino
, pm
->gen
, ancestor
,
3249 &pm
->update_refs
, &deleted_refs
,
3254 dm
= get_waiting_dir_move(sctx
, pm
->ino
);
3256 dm
->rmdir_ino
= rmdir_ino
;
3260 fs_path_reset(name
);
3263 ret
= get_cur_path(sctx
, pm
->ino
, pm
->gen
, to_path
);
3267 ret
= send_rename(sctx
, from_path
, to_path
);
3272 struct orphan_dir_info
*odi
;
3274 odi
= get_orphan_dir_info(sctx
, rmdir_ino
);
3276 /* already deleted */
3279 ret
= can_rmdir(sctx
, rmdir_ino
, odi
->gen
, sctx
->cur_ino
);
3285 name
= fs_path_alloc();
3290 ret
= get_cur_path(sctx
, rmdir_ino
, odi
->gen
, name
);
3293 ret
= send_rmdir(sctx
, name
);
3296 free_orphan_dir_info(sctx
, odi
);
3300 ret
= send_utimes(sctx
, pm
->ino
, pm
->gen
);
3305 * After rename/move, need to update the utimes of both new parent(s)
3306 * and old parent(s).
3308 list_for_each_entry(cur
, &pm
->update_refs
, list
) {
3310 * The parent inode might have been deleted in the send snapshot
3312 ret
= get_inode_info(sctx
->send_root
, cur
->dir
, NULL
,
3313 NULL
, NULL
, NULL
, NULL
, NULL
);
3314 if (ret
== -ENOENT
) {
3321 ret
= send_utimes(sctx
, cur
->dir
, cur
->dir_gen
);
3328 fs_path_free(from_path
);
3329 fs_path_free(to_path
);
3330 sctx
->send_progress
= orig_progress
;
3335 static void free_pending_move(struct send_ctx
*sctx
, struct pending_dir_move
*m
)
3337 if (!list_empty(&m
->list
))
3339 if (!RB_EMPTY_NODE(&m
->node
))
3340 rb_erase(&m
->node
, &sctx
->pending_dir_moves
);
3341 __free_recorded_refs(&m
->update_refs
);
3345 static void tail_append_pending_moves(struct pending_dir_move
*moves
,
3346 struct list_head
*stack
)
3348 if (list_empty(&moves
->list
)) {
3349 list_add_tail(&moves
->list
, stack
);
3352 list_splice_init(&moves
->list
, &list
);
3353 list_add_tail(&moves
->list
, stack
);
3354 list_splice_tail(&list
, stack
);
3358 static int apply_children_dir_moves(struct send_ctx
*sctx
)
3360 struct pending_dir_move
*pm
;
3361 struct list_head stack
;
3362 u64 parent_ino
= sctx
->cur_ino
;
3365 pm
= get_pending_dir_moves(sctx
, parent_ino
);
3369 INIT_LIST_HEAD(&stack
);
3370 tail_append_pending_moves(pm
, &stack
);
3372 while (!list_empty(&stack
)) {
3373 pm
= list_first_entry(&stack
, struct pending_dir_move
, list
);
3374 parent_ino
= pm
->ino
;
3375 ret
= apply_dir_move(sctx
, pm
);
3376 free_pending_move(sctx
, pm
);
3379 pm
= get_pending_dir_moves(sctx
, parent_ino
);
3381 tail_append_pending_moves(pm
, &stack
);
3386 while (!list_empty(&stack
)) {
3387 pm
= list_first_entry(&stack
, struct pending_dir_move
, list
);
3388 free_pending_move(sctx
, pm
);
3394 * We might need to delay a directory rename even when no ancestor directory
3395 * (in the send root) with a higher inode number than ours (sctx->cur_ino) was
3396 * renamed. This happens when we rename a directory to the old name (the name
3397 * in the parent root) of some other unrelated directory that got its rename
3398 * delayed due to some ancestor with higher number that got renamed.
3404 * |---- a/ (ino 257)
3405 * | |---- file (ino 260)
3407 * |---- b/ (ino 258)
3408 * |---- c/ (ino 259)
3412 * |---- a/ (ino 258)
3413 * |---- x/ (ino 259)
3414 * |---- y/ (ino 257)
3415 * |----- file (ino 260)
3417 * Here we can not rename 258 from 'b' to 'a' without the rename of inode 257
3418 * from 'a' to 'x/y' happening first, which in turn depends on the rename of
3419 * inode 259 from 'c' to 'x'. So the order of rename commands the send stream
3422 * 1 - rename 259 from 'c' to 'x'
3423 * 2 - rename 257 from 'a' to 'x/y'
3424 * 3 - rename 258 from 'b' to 'a'
3426 * Returns 1 if the rename of sctx->cur_ino needs to be delayed, 0 if it can
3427 * be done right away and < 0 on error.
3429 static int wait_for_dest_dir_move(struct send_ctx
*sctx
,
3430 struct recorded_ref
*parent_ref
,
3431 const bool is_orphan
)
3433 struct btrfs_fs_info
*fs_info
= sctx
->parent_root
->fs_info
;
3434 struct btrfs_path
*path
;
3435 struct btrfs_key key
;
3436 struct btrfs_key di_key
;
3437 struct btrfs_dir_item
*di
;
3441 struct waiting_dir_move
*wdm
;
3443 if (RB_EMPTY_ROOT(&sctx
->waiting_dir_moves
))
3446 path
= alloc_path_for_send();
3450 key
.objectid
= parent_ref
->dir
;
3451 key
.type
= BTRFS_DIR_ITEM_KEY
;
3452 key
.offset
= btrfs_name_hash(parent_ref
->name
, parent_ref
->name_len
);
3454 ret
= btrfs_search_slot(NULL
, sctx
->parent_root
, &key
, path
, 0, 0);
3457 } else if (ret
> 0) {
3462 di
= btrfs_match_dir_item_name(fs_info
, path
, parent_ref
->name
,
3463 parent_ref
->name_len
);
3469 * di_key.objectid has the number of the inode that has a dentry in the
3470 * parent directory with the same name that sctx->cur_ino is being
3471 * renamed to. We need to check if that inode is in the send root as
3472 * well and if it is currently marked as an inode with a pending rename,
3473 * if it is, we need to delay the rename of sctx->cur_ino as well, so
3474 * that it happens after that other inode is renamed.
3476 btrfs_dir_item_key_to_cpu(path
->nodes
[0], di
, &di_key
);
3477 if (di_key
.type
!= BTRFS_INODE_ITEM_KEY
) {
3482 ret
= get_inode_info(sctx
->parent_root
, di_key
.objectid
, NULL
,
3483 &left_gen
, NULL
, NULL
, NULL
, NULL
);
3486 ret
= get_inode_info(sctx
->send_root
, di_key
.objectid
, NULL
,
3487 &right_gen
, NULL
, NULL
, NULL
, NULL
);
3494 /* Different inode, no need to delay the rename of sctx->cur_ino */
3495 if (right_gen
!= left_gen
) {
3500 wdm
= get_waiting_dir_move(sctx
, di_key
.objectid
);
3501 if (wdm
&& !wdm
->orphanized
) {
3502 ret
= add_pending_dir_move(sctx
,
3504 sctx
->cur_inode_gen
,
3507 &sctx
->deleted_refs
,
3513 btrfs_free_path(path
);
3518 * Check if inode ino2, or any of its ancestors, is inode ino1.
3519 * Return 1 if true, 0 if false and < 0 on error.
3521 static int check_ino_in_path(struct btrfs_root
*root
,
3526 struct fs_path
*fs_path
)
3531 return ino1_gen
== ino2_gen
;
3533 while (ino
> BTRFS_FIRST_FREE_OBJECTID
) {
3538 fs_path_reset(fs_path
);
3539 ret
= get_first_ref(root
, ino
, &parent
, &parent_gen
, fs_path
);
3543 return parent_gen
== ino1_gen
;
3550 * Check if ino ino1 is an ancestor of inode ino2 in the given root for any
3551 * possible path (in case ino2 is not a directory and has multiple hard links).
3552 * Return 1 if true, 0 if false and < 0 on error.
3554 static int is_ancestor(struct btrfs_root
*root
,
3558 struct fs_path
*fs_path
)
3560 bool free_fs_path
= false;
3562 struct btrfs_path
*path
= NULL
;
3563 struct btrfs_key key
;
3566 fs_path
= fs_path_alloc();
3569 free_fs_path
= true;
3572 path
= alloc_path_for_send();
3578 key
.objectid
= ino2
;
3579 key
.type
= BTRFS_INODE_REF_KEY
;
3582 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
3587 struct extent_buffer
*leaf
= path
->nodes
[0];
3588 int slot
= path
->slots
[0];
3592 if (slot
>= btrfs_header_nritems(leaf
)) {
3593 ret
= btrfs_next_leaf(root
, path
);
3601 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
3602 if (key
.objectid
!= ino2
)
3604 if (key
.type
!= BTRFS_INODE_REF_KEY
&&
3605 key
.type
!= BTRFS_INODE_EXTREF_KEY
)
3608 item_size
= btrfs_item_size_nr(leaf
, slot
);
3609 while (cur_offset
< item_size
) {
3613 if (key
.type
== BTRFS_INODE_EXTREF_KEY
) {
3615 struct btrfs_inode_extref
*extref
;
3617 ptr
= btrfs_item_ptr_offset(leaf
, slot
);
3618 extref
= (struct btrfs_inode_extref
*)
3620 parent
= btrfs_inode_extref_parent(leaf
,
3622 cur_offset
+= sizeof(*extref
);
3623 cur_offset
+= btrfs_inode_extref_name_len(leaf
,
3626 parent
= key
.offset
;
3627 cur_offset
= item_size
;
3630 ret
= get_inode_info(root
, parent
, NULL
, &parent_gen
,
3631 NULL
, NULL
, NULL
, NULL
);
3634 ret
= check_ino_in_path(root
, ino1
, ino1_gen
,
3635 parent
, parent_gen
, fs_path
);
3643 btrfs_free_path(path
);
3645 fs_path_free(fs_path
);
3649 static int wait_for_parent_move(struct send_ctx
*sctx
,
3650 struct recorded_ref
*parent_ref
,
3651 const bool is_orphan
)
3654 u64 ino
= parent_ref
->dir
;
3655 u64 ino_gen
= parent_ref
->dir_gen
;
3656 u64 parent_ino_before
, parent_ino_after
;
3657 struct fs_path
*path_before
= NULL
;
3658 struct fs_path
*path_after
= NULL
;
3661 path_after
= fs_path_alloc();
3662 path_before
= fs_path_alloc();
3663 if (!path_after
|| !path_before
) {
3669 * Our current directory inode may not yet be renamed/moved because some
3670 * ancestor (immediate or not) has to be renamed/moved first. So find if
3671 * such ancestor exists and make sure our own rename/move happens after
3672 * that ancestor is processed to avoid path build infinite loops (done
3673 * at get_cur_path()).
3675 while (ino
> BTRFS_FIRST_FREE_OBJECTID
) {
3676 u64 parent_ino_after_gen
;
3678 if (is_waiting_for_move(sctx
, ino
)) {
3680 * If the current inode is an ancestor of ino in the
3681 * parent root, we need to delay the rename of the
3682 * current inode, otherwise don't delayed the rename
3683 * because we can end up with a circular dependency
3684 * of renames, resulting in some directories never
3685 * getting the respective rename operations issued in
3686 * the send stream or getting into infinite path build
3689 ret
= is_ancestor(sctx
->parent_root
,
3690 sctx
->cur_ino
, sctx
->cur_inode_gen
,
3696 fs_path_reset(path_before
);
3697 fs_path_reset(path_after
);
3699 ret
= get_first_ref(sctx
->send_root
, ino
, &parent_ino_after
,
3700 &parent_ino_after_gen
, path_after
);
3703 ret
= get_first_ref(sctx
->parent_root
, ino
, &parent_ino_before
,
3705 if (ret
< 0 && ret
!= -ENOENT
) {
3707 } else if (ret
== -ENOENT
) {
3712 len1
= fs_path_len(path_before
);
3713 len2
= fs_path_len(path_after
);
3714 if (ino
> sctx
->cur_ino
&&
3715 (parent_ino_before
!= parent_ino_after
|| len1
!= len2
||
3716 memcmp(path_before
->start
, path_after
->start
, len1
))) {
3719 ret
= get_inode_info(sctx
->parent_root
, ino
, NULL
,
3720 &parent_ino_gen
, NULL
, NULL
, NULL
,
3724 if (ino_gen
== parent_ino_gen
) {
3729 ino
= parent_ino_after
;
3730 ino_gen
= parent_ino_after_gen
;
3734 fs_path_free(path_before
);
3735 fs_path_free(path_after
);
3738 ret
= add_pending_dir_move(sctx
,
3740 sctx
->cur_inode_gen
,
3743 &sctx
->deleted_refs
,
3752 static int update_ref_path(struct send_ctx
*sctx
, struct recorded_ref
*ref
)
3755 struct fs_path
*new_path
;
3758 * Our reference's name member points to its full_path member string, so
3759 * we use here a new path.
3761 new_path
= fs_path_alloc();
3765 ret
= get_cur_path(sctx
, ref
->dir
, ref
->dir_gen
, new_path
);
3767 fs_path_free(new_path
);
3770 ret
= fs_path_add(new_path
, ref
->name
, ref
->name_len
);
3772 fs_path_free(new_path
);
3776 fs_path_free(ref
->full_path
);
3777 set_ref_path(ref
, new_path
);
3783 * This does all the move/link/unlink/rmdir magic.
3785 static int process_recorded_refs(struct send_ctx
*sctx
, int *pending_move
)
3787 struct btrfs_fs_info
*fs_info
= sctx
->send_root
->fs_info
;
3789 struct recorded_ref
*cur
;
3790 struct recorded_ref
*cur2
;
3791 struct list_head check_dirs
;
3792 struct fs_path
*valid_path
= NULL
;
3796 int did_overwrite
= 0;
3798 u64 last_dir_ino_rm
= 0;
3799 bool can_rename
= true;
3800 bool orphanized_dir
= false;
3801 bool orphanized_ancestor
= false;
3803 btrfs_debug(fs_info
, "process_recorded_refs %llu", sctx
->cur_ino
);
3806 * This should never happen as the root dir always has the same ref
3807 * which is always '..'
3809 BUG_ON(sctx
->cur_ino
<= BTRFS_FIRST_FREE_OBJECTID
);
3810 INIT_LIST_HEAD(&check_dirs
);
3812 valid_path
= fs_path_alloc();
3819 * First, check if the first ref of the current inode was overwritten
3820 * before. If yes, we know that the current inode was already orphanized
3821 * and thus use the orphan name. If not, we can use get_cur_path to
3822 * get the path of the first ref as it would like while receiving at
3823 * this point in time.
3824 * New inodes are always orphan at the beginning, so force to use the
3825 * orphan name in this case.
3826 * The first ref is stored in valid_path and will be updated if it
3827 * gets moved around.
3829 if (!sctx
->cur_inode_new
) {
3830 ret
= did_overwrite_first_ref(sctx
, sctx
->cur_ino
,
3831 sctx
->cur_inode_gen
);
3837 if (sctx
->cur_inode_new
|| did_overwrite
) {
3838 ret
= gen_unique_name(sctx
, sctx
->cur_ino
,
3839 sctx
->cur_inode_gen
, valid_path
);
3844 ret
= get_cur_path(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
,
3850 list_for_each_entry(cur
, &sctx
->new_refs
, list
) {
3852 * We may have refs where the parent directory does not exist
3853 * yet. This happens if the parent directories inum is higher
3854 * the the current inum. To handle this case, we create the
3855 * parent directory out of order. But we need to check if this
3856 * did already happen before due to other refs in the same dir.
3858 ret
= get_cur_inode_state(sctx
, cur
->dir
, cur
->dir_gen
);
3861 if (ret
== inode_state_will_create
) {
3864 * First check if any of the current inodes refs did
3865 * already create the dir.
3867 list_for_each_entry(cur2
, &sctx
->new_refs
, list
) {
3870 if (cur2
->dir
== cur
->dir
) {
3877 * If that did not happen, check if a previous inode
3878 * did already create the dir.
3881 ret
= did_create_dir(sctx
, cur
->dir
);
3885 ret
= send_create_inode(sctx
, cur
->dir
);
3892 * Check if this new ref would overwrite the first ref of
3893 * another unprocessed inode. If yes, orphanize the
3894 * overwritten inode. If we find an overwritten ref that is
3895 * not the first ref, simply unlink it.
3897 ret
= will_overwrite_ref(sctx
, cur
->dir
, cur
->dir_gen
,
3898 cur
->name
, cur
->name_len
,
3899 &ow_inode
, &ow_gen
, &ow_mode
);
3903 ret
= is_first_ref(sctx
->parent_root
,
3904 ow_inode
, cur
->dir
, cur
->name
,
3909 struct name_cache_entry
*nce
;
3910 struct waiting_dir_move
*wdm
;
3912 ret
= orphanize_inode(sctx
, ow_inode
, ow_gen
,
3916 if (S_ISDIR(ow_mode
))
3917 orphanized_dir
= true;
3920 * If ow_inode has its rename operation delayed
3921 * make sure that its orphanized name is used in
3922 * the source path when performing its rename
3925 if (is_waiting_for_move(sctx
, ow_inode
)) {
3926 wdm
= get_waiting_dir_move(sctx
,
3929 wdm
->orphanized
= true;
3933 * Make sure we clear our orphanized inode's
3934 * name from the name cache. This is because the
3935 * inode ow_inode might be an ancestor of some
3936 * other inode that will be orphanized as well
3937 * later and has an inode number greater than
3938 * sctx->send_progress. We need to prevent
3939 * future name lookups from using the old name
3940 * and get instead the orphan name.
3942 nce
= name_cache_search(sctx
, ow_inode
, ow_gen
);
3944 name_cache_delete(sctx
, nce
);
3949 * ow_inode might currently be an ancestor of
3950 * cur_ino, therefore compute valid_path (the
3951 * current path of cur_ino) again because it
3952 * might contain the pre-orphanization name of
3953 * ow_inode, which is no longer valid.
3955 ret
= is_ancestor(sctx
->parent_root
,
3957 sctx
->cur_ino
, NULL
);
3959 orphanized_ancestor
= true;
3960 fs_path_reset(valid_path
);
3961 ret
= get_cur_path(sctx
, sctx
->cur_ino
,
3962 sctx
->cur_inode_gen
,
3968 ret
= send_unlink(sctx
, cur
->full_path
);
3974 if (S_ISDIR(sctx
->cur_inode_mode
) && sctx
->parent_root
) {
3975 ret
= wait_for_dest_dir_move(sctx
, cur
, is_orphan
);
3984 if (S_ISDIR(sctx
->cur_inode_mode
) && sctx
->parent_root
&&
3986 ret
= wait_for_parent_move(sctx
, cur
, is_orphan
);
3996 * link/move the ref to the new place. If we have an orphan
3997 * inode, move it and update valid_path. If not, link or move
3998 * it depending on the inode mode.
4000 if (is_orphan
&& can_rename
) {
4001 ret
= send_rename(sctx
, valid_path
, cur
->full_path
);
4005 ret
= fs_path_copy(valid_path
, cur
->full_path
);
4008 } else if (can_rename
) {
4009 if (S_ISDIR(sctx
->cur_inode_mode
)) {
4011 * Dirs can't be linked, so move it. For moved
4012 * dirs, we always have one new and one deleted
4013 * ref. The deleted ref is ignored later.
4015 ret
= send_rename(sctx
, valid_path
,
4018 ret
= fs_path_copy(valid_path
,
4024 * We might have previously orphanized an inode
4025 * which is an ancestor of our current inode,
4026 * so our reference's full path, which was
4027 * computed before any such orphanizations, must
4030 if (orphanized_dir
) {
4031 ret
= update_ref_path(sctx
, cur
);
4035 ret
= send_link(sctx
, cur
->full_path
,
4041 ret
= dup_ref(cur
, &check_dirs
);
4046 if (S_ISDIR(sctx
->cur_inode_mode
) && sctx
->cur_inode_deleted
) {
4048 * Check if we can already rmdir the directory. If not,
4049 * orphanize it. For every dir item inside that gets deleted
4050 * later, we do this check again and rmdir it then if possible.
4051 * See the use of check_dirs for more details.
4053 ret
= can_rmdir(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
,
4058 ret
= send_rmdir(sctx
, valid_path
);
4061 } else if (!is_orphan
) {
4062 ret
= orphanize_inode(sctx
, sctx
->cur_ino
,
4063 sctx
->cur_inode_gen
, valid_path
);
4069 list_for_each_entry(cur
, &sctx
->deleted_refs
, list
) {
4070 ret
= dup_ref(cur
, &check_dirs
);
4074 } else if (S_ISDIR(sctx
->cur_inode_mode
) &&
4075 !list_empty(&sctx
->deleted_refs
)) {
4077 * We have a moved dir. Add the old parent to check_dirs
4079 cur
= list_entry(sctx
->deleted_refs
.next
, struct recorded_ref
,
4081 ret
= dup_ref(cur
, &check_dirs
);
4084 } else if (!S_ISDIR(sctx
->cur_inode_mode
)) {
4086 * We have a non dir inode. Go through all deleted refs and
4087 * unlink them if they were not already overwritten by other
4090 list_for_each_entry(cur
, &sctx
->deleted_refs
, list
) {
4091 ret
= did_overwrite_ref(sctx
, cur
->dir
, cur
->dir_gen
,
4092 sctx
->cur_ino
, sctx
->cur_inode_gen
,
4093 cur
->name
, cur
->name_len
);
4098 * If we orphanized any ancestor before, we need
4099 * to recompute the full path for deleted names,
4100 * since any such path was computed before we
4101 * processed any references and orphanized any
4104 if (orphanized_ancestor
) {
4105 ret
= update_ref_path(sctx
, cur
);
4109 ret
= send_unlink(sctx
, cur
->full_path
);
4113 ret
= dup_ref(cur
, &check_dirs
);
4118 * If the inode is still orphan, unlink the orphan. This may
4119 * happen when a previous inode did overwrite the first ref
4120 * of this inode and no new refs were added for the current
4121 * inode. Unlinking does not mean that the inode is deleted in
4122 * all cases. There may still be links to this inode in other
4126 ret
= send_unlink(sctx
, valid_path
);
4133 * We did collect all parent dirs where cur_inode was once located. We
4134 * now go through all these dirs and check if they are pending for
4135 * deletion and if it's finally possible to perform the rmdir now.
4136 * We also update the inode stats of the parent dirs here.
4138 list_for_each_entry(cur
, &check_dirs
, list
) {
4140 * In case we had refs into dirs that were not processed yet,
4141 * we don't need to do the utime and rmdir logic for these dirs.
4142 * The dir will be processed later.
4144 if (cur
->dir
> sctx
->cur_ino
)
4147 ret
= get_cur_inode_state(sctx
, cur
->dir
, cur
->dir_gen
);
4151 if (ret
== inode_state_did_create
||
4152 ret
== inode_state_no_change
) {
4153 /* TODO delayed utimes */
4154 ret
= send_utimes(sctx
, cur
->dir
, cur
->dir_gen
);
4157 } else if (ret
== inode_state_did_delete
&&
4158 cur
->dir
!= last_dir_ino_rm
) {
4159 ret
= can_rmdir(sctx
, cur
->dir
, cur
->dir_gen
,
4164 ret
= get_cur_path(sctx
, cur
->dir
,
4165 cur
->dir_gen
, valid_path
);
4168 ret
= send_rmdir(sctx
, valid_path
);
4171 last_dir_ino_rm
= cur
->dir
;
4179 __free_recorded_refs(&check_dirs
);
4180 free_recorded_refs(sctx
);
4181 fs_path_free(valid_path
);
4185 static int record_ref(struct btrfs_root
*root
, u64 dir
, struct fs_path
*name
,
4186 void *ctx
, struct list_head
*refs
)
4189 struct send_ctx
*sctx
= ctx
;
4193 p
= fs_path_alloc();
4197 ret
= get_inode_info(root
, dir
, NULL
, &gen
, NULL
, NULL
,
4202 ret
= get_cur_path(sctx
, dir
, gen
, p
);
4205 ret
= fs_path_add_path(p
, name
);
4209 ret
= __record_ref(refs
, dir
, gen
, p
);
4217 static int __record_new_ref(int num
, u64 dir
, int index
,
4218 struct fs_path
*name
,
4221 struct send_ctx
*sctx
= ctx
;
4222 return record_ref(sctx
->send_root
, dir
, name
, ctx
, &sctx
->new_refs
);
4226 static int __record_deleted_ref(int num
, u64 dir
, int index
,
4227 struct fs_path
*name
,
4230 struct send_ctx
*sctx
= ctx
;
4231 return record_ref(sctx
->parent_root
, dir
, name
, ctx
,
4232 &sctx
->deleted_refs
);
4235 static int record_new_ref(struct send_ctx
*sctx
)
4239 ret
= iterate_inode_ref(sctx
->send_root
, sctx
->left_path
,
4240 sctx
->cmp_key
, 0, __record_new_ref
, sctx
);
4249 static int record_deleted_ref(struct send_ctx
*sctx
)
4253 ret
= iterate_inode_ref(sctx
->parent_root
, sctx
->right_path
,
4254 sctx
->cmp_key
, 0, __record_deleted_ref
, sctx
);
4263 struct find_ref_ctx
{
4266 struct btrfs_root
*root
;
4267 struct fs_path
*name
;
4271 static int __find_iref(int num
, u64 dir
, int index
,
4272 struct fs_path
*name
,
4275 struct find_ref_ctx
*ctx
= ctx_
;
4279 if (dir
== ctx
->dir
&& fs_path_len(name
) == fs_path_len(ctx
->name
) &&
4280 strncmp(name
->start
, ctx
->name
->start
, fs_path_len(name
)) == 0) {
4282 * To avoid doing extra lookups we'll only do this if everything
4285 ret
= get_inode_info(ctx
->root
, dir
, NULL
, &dir_gen
, NULL
,
4289 if (dir_gen
!= ctx
->dir_gen
)
4291 ctx
->found_idx
= num
;
4297 static int find_iref(struct btrfs_root
*root
,
4298 struct btrfs_path
*path
,
4299 struct btrfs_key
*key
,
4300 u64 dir
, u64 dir_gen
, struct fs_path
*name
)
4303 struct find_ref_ctx ctx
;
4307 ctx
.dir_gen
= dir_gen
;
4311 ret
= iterate_inode_ref(root
, path
, key
, 0, __find_iref
, &ctx
);
4315 if (ctx
.found_idx
== -1)
4318 return ctx
.found_idx
;
4321 static int __record_changed_new_ref(int num
, u64 dir
, int index
,
4322 struct fs_path
*name
,
4327 struct send_ctx
*sctx
= ctx
;
4329 ret
= get_inode_info(sctx
->send_root
, dir
, NULL
, &dir_gen
, NULL
,
4334 ret
= find_iref(sctx
->parent_root
, sctx
->right_path
,
4335 sctx
->cmp_key
, dir
, dir_gen
, name
);
4337 ret
= __record_new_ref(num
, dir
, index
, name
, sctx
);
4344 static int __record_changed_deleted_ref(int num
, u64 dir
, int index
,
4345 struct fs_path
*name
,
4350 struct send_ctx
*sctx
= ctx
;
4352 ret
= get_inode_info(sctx
->parent_root
, dir
, NULL
, &dir_gen
, NULL
,
4357 ret
= find_iref(sctx
->send_root
, sctx
->left_path
, sctx
->cmp_key
,
4358 dir
, dir_gen
, name
);
4360 ret
= __record_deleted_ref(num
, dir
, index
, name
, sctx
);
4367 static int record_changed_ref(struct send_ctx
*sctx
)
4371 ret
= iterate_inode_ref(sctx
->send_root
, sctx
->left_path
,
4372 sctx
->cmp_key
, 0, __record_changed_new_ref
, sctx
);
4375 ret
= iterate_inode_ref(sctx
->parent_root
, sctx
->right_path
,
4376 sctx
->cmp_key
, 0, __record_changed_deleted_ref
, sctx
);
4386 * Record and process all refs at once. Needed when an inode changes the
4387 * generation number, which means that it was deleted and recreated.
4389 static int process_all_refs(struct send_ctx
*sctx
,
4390 enum btrfs_compare_tree_result cmd
)
4393 struct btrfs_root
*root
;
4394 struct btrfs_path
*path
;
4395 struct btrfs_key key
;
4396 struct btrfs_key found_key
;
4397 struct extent_buffer
*eb
;
4399 iterate_inode_ref_t cb
;
4400 int pending_move
= 0;
4402 path
= alloc_path_for_send();
4406 if (cmd
== BTRFS_COMPARE_TREE_NEW
) {
4407 root
= sctx
->send_root
;
4408 cb
= __record_new_ref
;
4409 } else if (cmd
== BTRFS_COMPARE_TREE_DELETED
) {
4410 root
= sctx
->parent_root
;
4411 cb
= __record_deleted_ref
;
4413 btrfs_err(sctx
->send_root
->fs_info
,
4414 "Wrong command %d in process_all_refs", cmd
);
4419 key
.objectid
= sctx
->cmp_key
->objectid
;
4420 key
.type
= BTRFS_INODE_REF_KEY
;
4422 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
4427 eb
= path
->nodes
[0];
4428 slot
= path
->slots
[0];
4429 if (slot
>= btrfs_header_nritems(eb
)) {
4430 ret
= btrfs_next_leaf(root
, path
);
4438 btrfs_item_key_to_cpu(eb
, &found_key
, slot
);
4440 if (found_key
.objectid
!= key
.objectid
||
4441 (found_key
.type
!= BTRFS_INODE_REF_KEY
&&
4442 found_key
.type
!= BTRFS_INODE_EXTREF_KEY
))
4445 ret
= iterate_inode_ref(root
, path
, &found_key
, 0, cb
, sctx
);
4451 btrfs_release_path(path
);
4454 * We don't actually care about pending_move as we are simply
4455 * re-creating this inode and will be rename'ing it into place once we
4456 * rename the parent directory.
4458 ret
= process_recorded_refs(sctx
, &pending_move
);
4460 btrfs_free_path(path
);
4464 static int send_set_xattr(struct send_ctx
*sctx
,
4465 struct fs_path
*path
,
4466 const char *name
, int name_len
,
4467 const char *data
, int data_len
)
4471 ret
= begin_cmd(sctx
, BTRFS_SEND_C_SET_XATTR
);
4475 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, path
);
4476 TLV_PUT_STRING(sctx
, BTRFS_SEND_A_XATTR_NAME
, name
, name_len
);
4477 TLV_PUT(sctx
, BTRFS_SEND_A_XATTR_DATA
, data
, data_len
);
4479 ret
= send_cmd(sctx
);
4486 static int send_remove_xattr(struct send_ctx
*sctx
,
4487 struct fs_path
*path
,
4488 const char *name
, int name_len
)
4492 ret
= begin_cmd(sctx
, BTRFS_SEND_C_REMOVE_XATTR
);
4496 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, path
);
4497 TLV_PUT_STRING(sctx
, BTRFS_SEND_A_XATTR_NAME
, name
, name_len
);
4499 ret
= send_cmd(sctx
);
4506 static int __process_new_xattr(int num
, struct btrfs_key
*di_key
,
4507 const char *name
, int name_len
,
4508 const char *data
, int data_len
,
4512 struct send_ctx
*sctx
= ctx
;
4514 struct posix_acl_xattr_header dummy_acl
;
4516 p
= fs_path_alloc();
4521 * This hack is needed because empty acls are stored as zero byte
4522 * data in xattrs. Problem with that is, that receiving these zero byte
4523 * acls will fail later. To fix this, we send a dummy acl list that
4524 * only contains the version number and no entries.
4526 if (!strncmp(name
, XATTR_NAME_POSIX_ACL_ACCESS
, name_len
) ||
4527 !strncmp(name
, XATTR_NAME_POSIX_ACL_DEFAULT
, name_len
)) {
4528 if (data_len
== 0) {
4529 dummy_acl
.a_version
=
4530 cpu_to_le32(POSIX_ACL_XATTR_VERSION
);
4531 data
= (char *)&dummy_acl
;
4532 data_len
= sizeof(dummy_acl
);
4536 ret
= get_cur_path(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
, p
);
4540 ret
= send_set_xattr(sctx
, p
, name
, name_len
, data
, data_len
);
4547 static int __process_deleted_xattr(int num
, struct btrfs_key
*di_key
,
4548 const char *name
, int name_len
,
4549 const char *data
, int data_len
,
4553 struct send_ctx
*sctx
= ctx
;
4556 p
= fs_path_alloc();
4560 ret
= get_cur_path(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
, p
);
4564 ret
= send_remove_xattr(sctx
, p
, name
, name_len
);
4571 static int process_new_xattr(struct send_ctx
*sctx
)
4575 ret
= iterate_dir_item(sctx
->send_root
, sctx
->left_path
,
4576 __process_new_xattr
, sctx
);
4581 static int process_deleted_xattr(struct send_ctx
*sctx
)
4583 return iterate_dir_item(sctx
->parent_root
, sctx
->right_path
,
4584 __process_deleted_xattr
, sctx
);
4587 struct find_xattr_ctx
{
4595 static int __find_xattr(int num
, struct btrfs_key
*di_key
,
4596 const char *name
, int name_len
,
4597 const char *data
, int data_len
,
4598 u8 type
, void *vctx
)
4600 struct find_xattr_ctx
*ctx
= vctx
;
4602 if (name_len
== ctx
->name_len
&&
4603 strncmp(name
, ctx
->name
, name_len
) == 0) {
4604 ctx
->found_idx
= num
;
4605 ctx
->found_data_len
= data_len
;
4606 ctx
->found_data
= kmemdup(data
, data_len
, GFP_KERNEL
);
4607 if (!ctx
->found_data
)
4614 static int find_xattr(struct btrfs_root
*root
,
4615 struct btrfs_path
*path
,
4616 struct btrfs_key
*key
,
4617 const char *name
, int name_len
,
4618 char **data
, int *data_len
)
4621 struct find_xattr_ctx ctx
;
4624 ctx
.name_len
= name_len
;
4626 ctx
.found_data
= NULL
;
4627 ctx
.found_data_len
= 0;
4629 ret
= iterate_dir_item(root
, path
, __find_xattr
, &ctx
);
4633 if (ctx
.found_idx
== -1)
4636 *data
= ctx
.found_data
;
4637 *data_len
= ctx
.found_data_len
;
4639 kfree(ctx
.found_data
);
4641 return ctx
.found_idx
;
4645 static int __process_changed_new_xattr(int num
, struct btrfs_key
*di_key
,
4646 const char *name
, int name_len
,
4647 const char *data
, int data_len
,
4651 struct send_ctx
*sctx
= ctx
;
4652 char *found_data
= NULL
;
4653 int found_data_len
= 0;
4655 ret
= find_xattr(sctx
->parent_root
, sctx
->right_path
,
4656 sctx
->cmp_key
, name
, name_len
, &found_data
,
4658 if (ret
== -ENOENT
) {
4659 ret
= __process_new_xattr(num
, di_key
, name
, name_len
, data
,
4660 data_len
, type
, ctx
);
4661 } else if (ret
>= 0) {
4662 if (data_len
!= found_data_len
||
4663 memcmp(data
, found_data
, data_len
)) {
4664 ret
= __process_new_xattr(num
, di_key
, name
, name_len
,
4665 data
, data_len
, type
, ctx
);
4675 static int __process_changed_deleted_xattr(int num
, struct btrfs_key
*di_key
,
4676 const char *name
, int name_len
,
4677 const char *data
, int data_len
,
4681 struct send_ctx
*sctx
= ctx
;
4683 ret
= find_xattr(sctx
->send_root
, sctx
->left_path
, sctx
->cmp_key
,
4684 name
, name_len
, NULL
, NULL
);
4686 ret
= __process_deleted_xattr(num
, di_key
, name
, name_len
, data
,
4687 data_len
, type
, ctx
);
4694 static int process_changed_xattr(struct send_ctx
*sctx
)
4698 ret
= iterate_dir_item(sctx
->send_root
, sctx
->left_path
,
4699 __process_changed_new_xattr
, sctx
);
4702 ret
= iterate_dir_item(sctx
->parent_root
, sctx
->right_path
,
4703 __process_changed_deleted_xattr
, sctx
);
4709 static int process_all_new_xattrs(struct send_ctx
*sctx
)
4712 struct btrfs_root
*root
;
4713 struct btrfs_path
*path
;
4714 struct btrfs_key key
;
4715 struct btrfs_key found_key
;
4716 struct extent_buffer
*eb
;
4719 path
= alloc_path_for_send();
4723 root
= sctx
->send_root
;
4725 key
.objectid
= sctx
->cmp_key
->objectid
;
4726 key
.type
= BTRFS_XATTR_ITEM_KEY
;
4728 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
4733 eb
= path
->nodes
[0];
4734 slot
= path
->slots
[0];
4735 if (slot
>= btrfs_header_nritems(eb
)) {
4736 ret
= btrfs_next_leaf(root
, path
);
4739 } else if (ret
> 0) {
4746 btrfs_item_key_to_cpu(eb
, &found_key
, slot
);
4747 if (found_key
.objectid
!= key
.objectid
||
4748 found_key
.type
!= key
.type
) {
4753 ret
= iterate_dir_item(root
, path
, __process_new_xattr
, sctx
);
4761 btrfs_free_path(path
);
4765 static ssize_t
fill_read_buf(struct send_ctx
*sctx
, u64 offset
, u32 len
)
4767 struct btrfs_root
*root
= sctx
->send_root
;
4768 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
4769 struct inode
*inode
;
4772 struct btrfs_key key
;
4773 pgoff_t index
= offset
>> PAGE_SHIFT
;
4775 unsigned pg_offset
= offset
& ~PAGE_MASK
;
4778 key
.objectid
= sctx
->cur_ino
;
4779 key
.type
= BTRFS_INODE_ITEM_KEY
;
4782 inode
= btrfs_iget(fs_info
->sb
, &key
, root
, NULL
);
4784 return PTR_ERR(inode
);
4786 if (offset
+ len
> i_size_read(inode
)) {
4787 if (offset
> i_size_read(inode
))
4790 len
= offset
- i_size_read(inode
);
4795 last_index
= (offset
+ len
- 1) >> PAGE_SHIFT
;
4797 /* initial readahead */
4798 memset(&sctx
->ra
, 0, sizeof(struct file_ra_state
));
4799 file_ra_state_init(&sctx
->ra
, inode
->i_mapping
);
4801 while (index
<= last_index
) {
4802 unsigned cur_len
= min_t(unsigned, len
,
4803 PAGE_SIZE
- pg_offset
);
4805 page
= find_lock_page(inode
->i_mapping
, index
);
4807 page_cache_sync_readahead(inode
->i_mapping
, &sctx
->ra
,
4808 NULL
, index
, last_index
+ 1 - index
);
4810 page
= find_or_create_page(inode
->i_mapping
, index
,
4818 if (PageReadahead(page
)) {
4819 page_cache_async_readahead(inode
->i_mapping
, &sctx
->ra
,
4820 NULL
, page
, index
, last_index
+ 1 - index
);
4823 if (!PageUptodate(page
)) {
4824 btrfs_readpage(NULL
, page
);
4826 if (!PageUptodate(page
)) {
4835 memcpy(sctx
->read_buf
+ ret
, addr
+ pg_offset
, cur_len
);
4850 * Read some bytes from the current inode/file and send a write command to
4853 static int send_write(struct send_ctx
*sctx
, u64 offset
, u32 len
)
4855 struct btrfs_fs_info
*fs_info
= sctx
->send_root
->fs_info
;
4858 ssize_t num_read
= 0;
4860 p
= fs_path_alloc();
4864 btrfs_debug(fs_info
, "send_write offset=%llu, len=%d", offset
, len
);
4866 num_read
= fill_read_buf(sctx
, offset
, len
);
4867 if (num_read
<= 0) {
4873 ret
= begin_cmd(sctx
, BTRFS_SEND_C_WRITE
);
4877 ret
= get_cur_path(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
, p
);
4881 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, p
);
4882 TLV_PUT_U64(sctx
, BTRFS_SEND_A_FILE_OFFSET
, offset
);
4883 TLV_PUT(sctx
, BTRFS_SEND_A_DATA
, sctx
->read_buf
, num_read
);
4885 ret
= send_cmd(sctx
);
4896 * Send a clone command to user space.
4898 static int send_clone(struct send_ctx
*sctx
,
4899 u64 offset
, u32 len
,
4900 struct clone_root
*clone_root
)
4906 btrfs_debug(sctx
->send_root
->fs_info
,
4907 "send_clone offset=%llu, len=%d, clone_root=%llu, clone_inode=%llu, clone_offset=%llu",
4908 offset
, len
, clone_root
->root
->objectid
, clone_root
->ino
,
4909 clone_root
->offset
);
4911 p
= fs_path_alloc();
4915 ret
= begin_cmd(sctx
, BTRFS_SEND_C_CLONE
);
4919 ret
= get_cur_path(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
, p
);
4923 TLV_PUT_U64(sctx
, BTRFS_SEND_A_FILE_OFFSET
, offset
);
4924 TLV_PUT_U64(sctx
, BTRFS_SEND_A_CLONE_LEN
, len
);
4925 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, p
);
4927 if (clone_root
->root
== sctx
->send_root
) {
4928 ret
= get_inode_info(sctx
->send_root
, clone_root
->ino
, NULL
,
4929 &gen
, NULL
, NULL
, NULL
, NULL
);
4932 ret
= get_cur_path(sctx
, clone_root
->ino
, gen
, p
);
4934 ret
= get_inode_path(clone_root
->root
, clone_root
->ino
, p
);
4940 * If the parent we're using has a received_uuid set then use that as
4941 * our clone source as that is what we will look for when doing a
4944 * This covers the case that we create a snapshot off of a received
4945 * subvolume and then use that as the parent and try to receive on a
4948 if (!btrfs_is_empty_uuid(clone_root
->root
->root_item
.received_uuid
))
4949 TLV_PUT_UUID(sctx
, BTRFS_SEND_A_CLONE_UUID
,
4950 clone_root
->root
->root_item
.received_uuid
);
4952 TLV_PUT_UUID(sctx
, BTRFS_SEND_A_CLONE_UUID
,
4953 clone_root
->root
->root_item
.uuid
);
4954 TLV_PUT_U64(sctx
, BTRFS_SEND_A_CLONE_CTRANSID
,
4955 le64_to_cpu(clone_root
->root
->root_item
.ctransid
));
4956 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_CLONE_PATH
, p
);
4957 TLV_PUT_U64(sctx
, BTRFS_SEND_A_CLONE_OFFSET
,
4958 clone_root
->offset
);
4960 ret
= send_cmd(sctx
);
4969 * Send an update extent command to user space.
4971 static int send_update_extent(struct send_ctx
*sctx
,
4972 u64 offset
, u32 len
)
4977 p
= fs_path_alloc();
4981 ret
= begin_cmd(sctx
, BTRFS_SEND_C_UPDATE_EXTENT
);
4985 ret
= get_cur_path(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
, p
);
4989 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, p
);
4990 TLV_PUT_U64(sctx
, BTRFS_SEND_A_FILE_OFFSET
, offset
);
4991 TLV_PUT_U64(sctx
, BTRFS_SEND_A_SIZE
, len
);
4993 ret
= send_cmd(sctx
);
5001 static int send_hole(struct send_ctx
*sctx
, u64 end
)
5003 struct fs_path
*p
= NULL
;
5004 u64 offset
= sctx
->cur_inode_last_extent
;
5008 if (sctx
->flags
& BTRFS_SEND_FLAG_NO_FILE_DATA
)
5009 return send_update_extent(sctx
, offset
, end
- offset
);
5011 p
= fs_path_alloc();
5014 ret
= get_cur_path(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
, p
);
5016 goto tlv_put_failure
;
5017 memset(sctx
->read_buf
, 0, BTRFS_SEND_READ_SIZE
);
5018 while (offset
< end
) {
5019 len
= min_t(u64
, end
- offset
, BTRFS_SEND_READ_SIZE
);
5021 ret
= begin_cmd(sctx
, BTRFS_SEND_C_WRITE
);
5024 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, p
);
5025 TLV_PUT_U64(sctx
, BTRFS_SEND_A_FILE_OFFSET
, offset
);
5026 TLV_PUT(sctx
, BTRFS_SEND_A_DATA
, sctx
->read_buf
, len
);
5027 ret
= send_cmd(sctx
);
5037 static int send_extent_data(struct send_ctx
*sctx
,
5043 if (sctx
->flags
& BTRFS_SEND_FLAG_NO_FILE_DATA
)
5044 return send_update_extent(sctx
, offset
, len
);
5046 while (sent
< len
) {
5047 u64 size
= len
- sent
;
5050 if (size
> BTRFS_SEND_READ_SIZE
)
5051 size
= BTRFS_SEND_READ_SIZE
;
5052 ret
= send_write(sctx
, offset
+ sent
, size
);
5062 static int clone_range(struct send_ctx
*sctx
,
5063 struct clone_root
*clone_root
,
5064 const u64 disk_byte
,
5069 struct btrfs_path
*path
;
5070 struct btrfs_key key
;
5074 * Prevent cloning from a zero offset with a length matching the sector
5075 * size because in some scenarios this will make the receiver fail.
5077 * For example, if in the source filesystem the extent at offset 0
5078 * has a length of sectorsize and it was written using direct IO, then
5079 * it can never be an inline extent (even if compression is enabled).
5080 * Then this extent can be cloned in the original filesystem to a non
5081 * zero file offset, but it may not be possible to clone in the
5082 * destination filesystem because it can be inlined due to compression
5083 * on the destination filesystem (as the receiver's write operations are
5084 * always done using buffered IO). The same happens when the original
5085 * filesystem does not have compression enabled but the destination
5088 if (clone_root
->offset
== 0 &&
5089 len
== sctx
->send_root
->fs_info
->sectorsize
)
5090 return send_extent_data(sctx
, offset
, len
);
5092 path
= alloc_path_for_send();
5097 * We can't send a clone operation for the entire range if we find
5098 * extent items in the respective range in the source file that
5099 * refer to different extents or if we find holes.
5100 * So check for that and do a mix of clone and regular write/copy
5101 * operations if needed.
5105 * mkfs.btrfs -f /dev/sda
5106 * mount /dev/sda /mnt
5107 * xfs_io -f -c "pwrite -S 0xaa 0K 100K" /mnt/foo
5108 * cp --reflink=always /mnt/foo /mnt/bar
5109 * xfs_io -c "pwrite -S 0xbb 50K 50K" /mnt/foo
5110 * btrfs subvolume snapshot -r /mnt /mnt/snap
5112 * If when we send the snapshot and we are processing file bar (which
5113 * has a higher inode number than foo) we blindly send a clone operation
5114 * for the [0, 100K[ range from foo to bar, the receiver ends up getting
5115 * a file bar that matches the content of file foo - iow, doesn't match
5116 * the content from bar in the original filesystem.
5118 key
.objectid
= clone_root
->ino
;
5119 key
.type
= BTRFS_EXTENT_DATA_KEY
;
5120 key
.offset
= clone_root
->offset
;
5121 ret
= btrfs_search_slot(NULL
, clone_root
->root
, &key
, path
, 0, 0);
5124 if (ret
> 0 && path
->slots
[0] > 0) {
5125 btrfs_item_key_to_cpu(path
->nodes
[0], &key
, path
->slots
[0] - 1);
5126 if (key
.objectid
== clone_root
->ino
&&
5127 key
.type
== BTRFS_EXTENT_DATA_KEY
)
5132 struct extent_buffer
*leaf
= path
->nodes
[0];
5133 int slot
= path
->slots
[0];
5134 struct btrfs_file_extent_item
*ei
;
5139 if (slot
>= btrfs_header_nritems(leaf
)) {
5140 ret
= btrfs_next_leaf(clone_root
->root
, path
);
5148 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
5151 * We might have an implicit trailing hole (NO_HOLES feature
5152 * enabled). We deal with it after leaving this loop.
5154 if (key
.objectid
!= clone_root
->ino
||
5155 key
.type
!= BTRFS_EXTENT_DATA_KEY
)
5158 ei
= btrfs_item_ptr(leaf
, slot
, struct btrfs_file_extent_item
);
5159 type
= btrfs_file_extent_type(leaf
, ei
);
5160 if (type
== BTRFS_FILE_EXTENT_INLINE
) {
5161 ext_len
= btrfs_file_extent_inline_len(leaf
, slot
, ei
);
5162 ext_len
= PAGE_ALIGN(ext_len
);
5164 ext_len
= btrfs_file_extent_num_bytes(leaf
, ei
);
5167 if (key
.offset
+ ext_len
<= clone_root
->offset
)
5170 if (key
.offset
> clone_root
->offset
) {
5171 /* Implicit hole, NO_HOLES feature enabled. */
5172 u64 hole_len
= key
.offset
- clone_root
->offset
;
5176 ret
= send_extent_data(sctx
, offset
, hole_len
);
5184 clone_root
->offset
+= hole_len
;
5185 data_offset
+= hole_len
;
5188 if (key
.offset
>= clone_root
->offset
+ len
)
5191 clone_len
= min_t(u64
, ext_len
, len
);
5193 if (btrfs_file_extent_disk_bytenr(leaf
, ei
) == disk_byte
&&
5194 btrfs_file_extent_offset(leaf
, ei
) == data_offset
)
5195 ret
= send_clone(sctx
, offset
, clone_len
, clone_root
);
5197 ret
= send_extent_data(sctx
, offset
, clone_len
);
5205 offset
+= clone_len
;
5206 clone_root
->offset
+= clone_len
;
5207 data_offset
+= clone_len
;
5213 ret
= send_extent_data(sctx
, offset
, len
);
5217 btrfs_free_path(path
);
5221 static int send_write_or_clone(struct send_ctx
*sctx
,
5222 struct btrfs_path
*path
,
5223 struct btrfs_key
*key
,
5224 struct clone_root
*clone_root
)
5227 struct btrfs_file_extent_item
*ei
;
5228 u64 offset
= key
->offset
;
5231 u64 bs
= sctx
->send_root
->fs_info
->sb
->s_blocksize
;
5233 ei
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
5234 struct btrfs_file_extent_item
);
5235 type
= btrfs_file_extent_type(path
->nodes
[0], ei
);
5236 if (type
== BTRFS_FILE_EXTENT_INLINE
) {
5237 len
= btrfs_file_extent_inline_len(path
->nodes
[0],
5238 path
->slots
[0], ei
);
5240 * it is possible the inline item won't cover the whole page,
5241 * but there may be items after this page. Make
5242 * sure to send the whole thing
5244 len
= PAGE_ALIGN(len
);
5246 len
= btrfs_file_extent_num_bytes(path
->nodes
[0], ei
);
5249 if (offset
+ len
> sctx
->cur_inode_size
)
5250 len
= sctx
->cur_inode_size
- offset
;
5256 if (clone_root
&& IS_ALIGNED(offset
+ len
, bs
)) {
5260 disk_byte
= btrfs_file_extent_disk_bytenr(path
->nodes
[0], ei
);
5261 data_offset
= btrfs_file_extent_offset(path
->nodes
[0], ei
);
5262 ret
= clone_range(sctx
, clone_root
, disk_byte
, data_offset
,
5265 ret
= send_extent_data(sctx
, offset
, len
);
5271 static int is_extent_unchanged(struct send_ctx
*sctx
,
5272 struct btrfs_path
*left_path
,
5273 struct btrfs_key
*ekey
)
5276 struct btrfs_key key
;
5277 struct btrfs_path
*path
= NULL
;
5278 struct extent_buffer
*eb
;
5280 struct btrfs_key found_key
;
5281 struct btrfs_file_extent_item
*ei
;
5286 u64 left_offset_fixed
;
5294 path
= alloc_path_for_send();
5298 eb
= left_path
->nodes
[0];
5299 slot
= left_path
->slots
[0];
5300 ei
= btrfs_item_ptr(eb
, slot
, struct btrfs_file_extent_item
);
5301 left_type
= btrfs_file_extent_type(eb
, ei
);
5303 if (left_type
!= BTRFS_FILE_EXTENT_REG
) {
5307 left_disknr
= btrfs_file_extent_disk_bytenr(eb
, ei
);
5308 left_len
= btrfs_file_extent_num_bytes(eb
, ei
);
5309 left_offset
= btrfs_file_extent_offset(eb
, ei
);
5310 left_gen
= btrfs_file_extent_generation(eb
, ei
);
5313 * Following comments will refer to these graphics. L is the left
5314 * extents which we are checking at the moment. 1-8 are the right
5315 * extents that we iterate.
5318 * |-1-|-2a-|-3-|-4-|-5-|-6-|
5321 * |--1--|-2b-|...(same as above)
5323 * Alternative situation. Happens on files where extents got split.
5325 * |-----------7-----------|-6-|
5327 * Alternative situation. Happens on files which got larger.
5330 * Nothing follows after 8.
5333 key
.objectid
= ekey
->objectid
;
5334 key
.type
= BTRFS_EXTENT_DATA_KEY
;
5335 key
.offset
= ekey
->offset
;
5336 ret
= btrfs_search_slot_for_read(sctx
->parent_root
, &key
, path
, 0, 0);
5345 * Handle special case where the right side has no extents at all.
5347 eb
= path
->nodes
[0];
5348 slot
= path
->slots
[0];
5349 btrfs_item_key_to_cpu(eb
, &found_key
, slot
);
5350 if (found_key
.objectid
!= key
.objectid
||
5351 found_key
.type
!= key
.type
) {
5352 /* If we're a hole then just pretend nothing changed */
5353 ret
= (left_disknr
) ? 0 : 1;
5358 * We're now on 2a, 2b or 7.
5361 while (key
.offset
< ekey
->offset
+ left_len
) {
5362 ei
= btrfs_item_ptr(eb
, slot
, struct btrfs_file_extent_item
);
5363 right_type
= btrfs_file_extent_type(eb
, ei
);
5364 if (right_type
!= BTRFS_FILE_EXTENT_REG
&&
5365 right_type
!= BTRFS_FILE_EXTENT_INLINE
) {
5370 if (right_type
== BTRFS_FILE_EXTENT_INLINE
) {
5371 right_len
= btrfs_file_extent_inline_len(eb
, slot
, ei
);
5372 right_len
= PAGE_ALIGN(right_len
);
5374 right_len
= btrfs_file_extent_num_bytes(eb
, ei
);
5378 * Are we at extent 8? If yes, we know the extent is changed.
5379 * This may only happen on the first iteration.
5381 if (found_key
.offset
+ right_len
<= ekey
->offset
) {
5382 /* If we're a hole just pretend nothing changed */
5383 ret
= (left_disknr
) ? 0 : 1;
5388 * We just wanted to see if when we have an inline extent, what
5389 * follows it is a regular extent (wanted to check the above
5390 * condition for inline extents too). This should normally not
5391 * happen but it's possible for example when we have an inline
5392 * compressed extent representing data with a size matching
5393 * the page size (currently the same as sector size).
5395 if (right_type
== BTRFS_FILE_EXTENT_INLINE
) {
5400 right_disknr
= btrfs_file_extent_disk_bytenr(eb
, ei
);
5401 right_offset
= btrfs_file_extent_offset(eb
, ei
);
5402 right_gen
= btrfs_file_extent_generation(eb
, ei
);
5404 left_offset_fixed
= left_offset
;
5405 if (key
.offset
< ekey
->offset
) {
5406 /* Fix the right offset for 2a and 7. */
5407 right_offset
+= ekey
->offset
- key
.offset
;
5409 /* Fix the left offset for all behind 2a and 2b */
5410 left_offset_fixed
+= key
.offset
- ekey
->offset
;
5414 * Check if we have the same extent.
5416 if (left_disknr
!= right_disknr
||
5417 left_offset_fixed
!= right_offset
||
5418 left_gen
!= right_gen
) {
5424 * Go to the next extent.
5426 ret
= btrfs_next_item(sctx
->parent_root
, path
);
5430 eb
= path
->nodes
[0];
5431 slot
= path
->slots
[0];
5432 btrfs_item_key_to_cpu(eb
, &found_key
, slot
);
5434 if (ret
|| found_key
.objectid
!= key
.objectid
||
5435 found_key
.type
!= key
.type
) {
5436 key
.offset
+= right_len
;
5439 if (found_key
.offset
!= key
.offset
+ right_len
) {
5447 * We're now behind the left extent (treat as unchanged) or at the end
5448 * of the right side (treat as changed).
5450 if (key
.offset
>= ekey
->offset
+ left_len
)
5457 btrfs_free_path(path
);
5461 static int get_last_extent(struct send_ctx
*sctx
, u64 offset
)
5463 struct btrfs_path
*path
;
5464 struct btrfs_root
*root
= sctx
->send_root
;
5465 struct btrfs_file_extent_item
*fi
;
5466 struct btrfs_key key
;
5471 path
= alloc_path_for_send();
5475 sctx
->cur_inode_last_extent
= 0;
5477 key
.objectid
= sctx
->cur_ino
;
5478 key
.type
= BTRFS_EXTENT_DATA_KEY
;
5479 key
.offset
= offset
;
5480 ret
= btrfs_search_slot_for_read(root
, &key
, path
, 0, 1);
5484 btrfs_item_key_to_cpu(path
->nodes
[0], &key
, path
->slots
[0]);
5485 if (key
.objectid
!= sctx
->cur_ino
|| key
.type
!= BTRFS_EXTENT_DATA_KEY
)
5488 fi
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
5489 struct btrfs_file_extent_item
);
5490 type
= btrfs_file_extent_type(path
->nodes
[0], fi
);
5491 if (type
== BTRFS_FILE_EXTENT_INLINE
) {
5492 u64 size
= btrfs_file_extent_inline_len(path
->nodes
[0],
5493 path
->slots
[0], fi
);
5494 extent_end
= ALIGN(key
.offset
+ size
,
5495 sctx
->send_root
->fs_info
->sectorsize
);
5497 extent_end
= key
.offset
+
5498 btrfs_file_extent_num_bytes(path
->nodes
[0], fi
);
5500 sctx
->cur_inode_last_extent
= extent_end
;
5502 btrfs_free_path(path
);
5506 static int range_is_hole_in_parent(struct send_ctx
*sctx
,
5510 struct btrfs_path
*path
;
5511 struct btrfs_key key
;
5512 struct btrfs_root
*root
= sctx
->parent_root
;
5513 u64 search_start
= start
;
5516 path
= alloc_path_for_send();
5520 key
.objectid
= sctx
->cur_ino
;
5521 key
.type
= BTRFS_EXTENT_DATA_KEY
;
5522 key
.offset
= search_start
;
5523 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
5526 if (ret
> 0 && path
->slots
[0] > 0)
5529 while (search_start
< end
) {
5530 struct extent_buffer
*leaf
= path
->nodes
[0];
5531 int slot
= path
->slots
[0];
5532 struct btrfs_file_extent_item
*fi
;
5535 if (slot
>= btrfs_header_nritems(leaf
)) {
5536 ret
= btrfs_next_leaf(root
, path
);
5544 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
5545 if (key
.objectid
< sctx
->cur_ino
||
5546 key
.type
< BTRFS_EXTENT_DATA_KEY
)
5548 if (key
.objectid
> sctx
->cur_ino
||
5549 key
.type
> BTRFS_EXTENT_DATA_KEY
||
5553 fi
= btrfs_item_ptr(leaf
, slot
, struct btrfs_file_extent_item
);
5554 if (btrfs_file_extent_type(leaf
, fi
) ==
5555 BTRFS_FILE_EXTENT_INLINE
) {
5556 u64 size
= btrfs_file_extent_inline_len(leaf
, slot
, fi
);
5558 extent_end
= ALIGN(key
.offset
+ size
,
5559 root
->fs_info
->sectorsize
);
5561 extent_end
= key
.offset
+
5562 btrfs_file_extent_num_bytes(leaf
, fi
);
5564 if (extent_end
<= start
)
5566 if (btrfs_file_extent_disk_bytenr(leaf
, fi
) == 0) {
5567 search_start
= extent_end
;
5577 btrfs_free_path(path
);
5581 static int maybe_send_hole(struct send_ctx
*sctx
, struct btrfs_path
*path
,
5582 struct btrfs_key
*key
)
5584 struct btrfs_file_extent_item
*fi
;
5589 if (sctx
->cur_ino
!= key
->objectid
|| !need_send_hole(sctx
))
5592 if (sctx
->cur_inode_last_extent
== (u64
)-1) {
5593 ret
= get_last_extent(sctx
, key
->offset
- 1);
5598 fi
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
5599 struct btrfs_file_extent_item
);
5600 type
= btrfs_file_extent_type(path
->nodes
[0], fi
);
5601 if (type
== BTRFS_FILE_EXTENT_INLINE
) {
5602 u64 size
= btrfs_file_extent_inline_len(path
->nodes
[0],
5603 path
->slots
[0], fi
);
5604 extent_end
= ALIGN(key
->offset
+ size
,
5605 sctx
->send_root
->fs_info
->sectorsize
);
5607 extent_end
= key
->offset
+
5608 btrfs_file_extent_num_bytes(path
->nodes
[0], fi
);
5611 if (path
->slots
[0] == 0 &&
5612 sctx
->cur_inode_last_extent
< key
->offset
) {
5614 * We might have skipped entire leafs that contained only
5615 * file extent items for our current inode. These leafs have
5616 * a generation number smaller (older) than the one in the
5617 * current leaf and the leaf our last extent came from, and
5618 * are located between these 2 leafs.
5620 ret
= get_last_extent(sctx
, key
->offset
- 1);
5625 if (sctx
->cur_inode_last_extent
< key
->offset
) {
5626 ret
= range_is_hole_in_parent(sctx
,
5627 sctx
->cur_inode_last_extent
,
5632 ret
= send_hole(sctx
, key
->offset
);
5636 sctx
->cur_inode_last_extent
= extent_end
;
5640 static int process_extent(struct send_ctx
*sctx
,
5641 struct btrfs_path
*path
,
5642 struct btrfs_key
*key
)
5644 struct clone_root
*found_clone
= NULL
;
5647 if (S_ISLNK(sctx
->cur_inode_mode
))
5650 if (sctx
->parent_root
&& !sctx
->cur_inode_new
) {
5651 ret
= is_extent_unchanged(sctx
, path
, key
);
5659 struct btrfs_file_extent_item
*ei
;
5662 ei
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
5663 struct btrfs_file_extent_item
);
5664 type
= btrfs_file_extent_type(path
->nodes
[0], ei
);
5665 if (type
== BTRFS_FILE_EXTENT_PREALLOC
||
5666 type
== BTRFS_FILE_EXTENT_REG
) {
5668 * The send spec does not have a prealloc command yet,
5669 * so just leave a hole for prealloc'ed extents until
5670 * we have enough commands queued up to justify rev'ing
5673 if (type
== BTRFS_FILE_EXTENT_PREALLOC
) {
5678 /* Have a hole, just skip it. */
5679 if (btrfs_file_extent_disk_bytenr(path
->nodes
[0], ei
) == 0) {
5686 ret
= find_extent_clone(sctx
, path
, key
->objectid
, key
->offset
,
5687 sctx
->cur_inode_size
, &found_clone
);
5688 if (ret
!= -ENOENT
&& ret
< 0)
5691 ret
= send_write_or_clone(sctx
, path
, key
, found_clone
);
5695 ret
= maybe_send_hole(sctx
, path
, key
);
5700 static int process_all_extents(struct send_ctx
*sctx
)
5703 struct btrfs_root
*root
;
5704 struct btrfs_path
*path
;
5705 struct btrfs_key key
;
5706 struct btrfs_key found_key
;
5707 struct extent_buffer
*eb
;
5710 root
= sctx
->send_root
;
5711 path
= alloc_path_for_send();
5715 key
.objectid
= sctx
->cmp_key
->objectid
;
5716 key
.type
= BTRFS_EXTENT_DATA_KEY
;
5718 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
5723 eb
= path
->nodes
[0];
5724 slot
= path
->slots
[0];
5726 if (slot
>= btrfs_header_nritems(eb
)) {
5727 ret
= btrfs_next_leaf(root
, path
);
5730 } else if (ret
> 0) {
5737 btrfs_item_key_to_cpu(eb
, &found_key
, slot
);
5739 if (found_key
.objectid
!= key
.objectid
||
5740 found_key
.type
!= key
.type
) {
5745 ret
= process_extent(sctx
, path
, &found_key
);
5753 btrfs_free_path(path
);
5757 static int process_recorded_refs_if_needed(struct send_ctx
*sctx
, int at_end
,
5759 int *refs_processed
)
5763 if (sctx
->cur_ino
== 0)
5765 if (!at_end
&& sctx
->cur_ino
== sctx
->cmp_key
->objectid
&&
5766 sctx
->cmp_key
->type
<= BTRFS_INODE_EXTREF_KEY
)
5768 if (list_empty(&sctx
->new_refs
) && list_empty(&sctx
->deleted_refs
))
5771 ret
= process_recorded_refs(sctx
, pending_move
);
5775 *refs_processed
= 1;
5780 static int finish_inode_if_needed(struct send_ctx
*sctx
, int at_end
)
5791 int pending_move
= 0;
5792 int refs_processed
= 0;
5794 ret
= process_recorded_refs_if_needed(sctx
, at_end
, &pending_move
,
5800 * We have processed the refs and thus need to advance send_progress.
5801 * Now, calls to get_cur_xxx will take the updated refs of the current
5802 * inode into account.
5804 * On the other hand, if our current inode is a directory and couldn't
5805 * be moved/renamed because its parent was renamed/moved too and it has
5806 * a higher inode number, we can only move/rename our current inode
5807 * after we moved/renamed its parent. Therefore in this case operate on
5808 * the old path (pre move/rename) of our current inode, and the
5809 * move/rename will be performed later.
5811 if (refs_processed
&& !pending_move
)
5812 sctx
->send_progress
= sctx
->cur_ino
+ 1;
5814 if (sctx
->cur_ino
== 0 || sctx
->cur_inode_deleted
)
5816 if (!at_end
&& sctx
->cmp_key
->objectid
== sctx
->cur_ino
)
5819 ret
= get_inode_info(sctx
->send_root
, sctx
->cur_ino
, NULL
, NULL
,
5820 &left_mode
, &left_uid
, &left_gid
, NULL
);
5824 if (!sctx
->parent_root
|| sctx
->cur_inode_new
) {
5826 if (!S_ISLNK(sctx
->cur_inode_mode
))
5829 ret
= get_inode_info(sctx
->parent_root
, sctx
->cur_ino
,
5830 NULL
, NULL
, &right_mode
, &right_uid
,
5835 if (left_uid
!= right_uid
|| left_gid
!= right_gid
)
5837 if (!S_ISLNK(sctx
->cur_inode_mode
) && left_mode
!= right_mode
)
5841 if (S_ISREG(sctx
->cur_inode_mode
)) {
5842 if (need_send_hole(sctx
)) {
5843 if (sctx
->cur_inode_last_extent
== (u64
)-1 ||
5844 sctx
->cur_inode_last_extent
<
5845 sctx
->cur_inode_size
) {
5846 ret
= get_last_extent(sctx
, (u64
)-1);
5850 if (sctx
->cur_inode_last_extent
<
5851 sctx
->cur_inode_size
) {
5852 ret
= send_hole(sctx
, sctx
->cur_inode_size
);
5857 ret
= send_truncate(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
,
5858 sctx
->cur_inode_size
);
5864 ret
= send_chown(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
,
5865 left_uid
, left_gid
);
5870 ret
= send_chmod(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
,
5877 * If other directory inodes depended on our current directory
5878 * inode's move/rename, now do their move/rename operations.
5880 if (!is_waiting_for_move(sctx
, sctx
->cur_ino
)) {
5881 ret
= apply_children_dir_moves(sctx
);
5885 * Need to send that every time, no matter if it actually
5886 * changed between the two trees as we have done changes to
5887 * the inode before. If our inode is a directory and it's
5888 * waiting to be moved/renamed, we will send its utimes when
5889 * it's moved/renamed, therefore we don't need to do it here.
5891 sctx
->send_progress
= sctx
->cur_ino
+ 1;
5892 ret
= send_utimes(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
);
5901 static int changed_inode(struct send_ctx
*sctx
,
5902 enum btrfs_compare_tree_result result
)
5905 struct btrfs_key
*key
= sctx
->cmp_key
;
5906 struct btrfs_inode_item
*left_ii
= NULL
;
5907 struct btrfs_inode_item
*right_ii
= NULL
;
5911 sctx
->cur_ino
= key
->objectid
;
5912 sctx
->cur_inode_new_gen
= 0;
5913 sctx
->cur_inode_last_extent
= (u64
)-1;
5916 * Set send_progress to current inode. This will tell all get_cur_xxx
5917 * functions that the current inode's refs are not updated yet. Later,
5918 * when process_recorded_refs is finished, it is set to cur_ino + 1.
5920 sctx
->send_progress
= sctx
->cur_ino
;
5922 if (result
== BTRFS_COMPARE_TREE_NEW
||
5923 result
== BTRFS_COMPARE_TREE_CHANGED
) {
5924 left_ii
= btrfs_item_ptr(sctx
->left_path
->nodes
[0],
5925 sctx
->left_path
->slots
[0],
5926 struct btrfs_inode_item
);
5927 left_gen
= btrfs_inode_generation(sctx
->left_path
->nodes
[0],
5930 right_ii
= btrfs_item_ptr(sctx
->right_path
->nodes
[0],
5931 sctx
->right_path
->slots
[0],
5932 struct btrfs_inode_item
);
5933 right_gen
= btrfs_inode_generation(sctx
->right_path
->nodes
[0],
5936 if (result
== BTRFS_COMPARE_TREE_CHANGED
) {
5937 right_ii
= btrfs_item_ptr(sctx
->right_path
->nodes
[0],
5938 sctx
->right_path
->slots
[0],
5939 struct btrfs_inode_item
);
5941 right_gen
= btrfs_inode_generation(sctx
->right_path
->nodes
[0],
5945 * The cur_ino = root dir case is special here. We can't treat
5946 * the inode as deleted+reused because it would generate a
5947 * stream that tries to delete/mkdir the root dir.
5949 if (left_gen
!= right_gen
&&
5950 sctx
->cur_ino
!= BTRFS_FIRST_FREE_OBJECTID
)
5951 sctx
->cur_inode_new_gen
= 1;
5954 if (result
== BTRFS_COMPARE_TREE_NEW
) {
5955 sctx
->cur_inode_gen
= left_gen
;
5956 sctx
->cur_inode_new
= 1;
5957 sctx
->cur_inode_deleted
= 0;
5958 sctx
->cur_inode_size
= btrfs_inode_size(
5959 sctx
->left_path
->nodes
[0], left_ii
);
5960 sctx
->cur_inode_mode
= btrfs_inode_mode(
5961 sctx
->left_path
->nodes
[0], left_ii
);
5962 sctx
->cur_inode_rdev
= btrfs_inode_rdev(
5963 sctx
->left_path
->nodes
[0], left_ii
);
5964 if (sctx
->cur_ino
!= BTRFS_FIRST_FREE_OBJECTID
)
5965 ret
= send_create_inode_if_needed(sctx
);
5966 } else if (result
== BTRFS_COMPARE_TREE_DELETED
) {
5967 sctx
->cur_inode_gen
= right_gen
;
5968 sctx
->cur_inode_new
= 0;
5969 sctx
->cur_inode_deleted
= 1;
5970 sctx
->cur_inode_size
= btrfs_inode_size(
5971 sctx
->right_path
->nodes
[0], right_ii
);
5972 sctx
->cur_inode_mode
= btrfs_inode_mode(
5973 sctx
->right_path
->nodes
[0], right_ii
);
5974 } else if (result
== BTRFS_COMPARE_TREE_CHANGED
) {
5976 * We need to do some special handling in case the inode was
5977 * reported as changed with a changed generation number. This
5978 * means that the original inode was deleted and new inode
5979 * reused the same inum. So we have to treat the old inode as
5980 * deleted and the new one as new.
5982 if (sctx
->cur_inode_new_gen
) {
5984 * First, process the inode as if it was deleted.
5986 sctx
->cur_inode_gen
= right_gen
;
5987 sctx
->cur_inode_new
= 0;
5988 sctx
->cur_inode_deleted
= 1;
5989 sctx
->cur_inode_size
= btrfs_inode_size(
5990 sctx
->right_path
->nodes
[0], right_ii
);
5991 sctx
->cur_inode_mode
= btrfs_inode_mode(
5992 sctx
->right_path
->nodes
[0], right_ii
);
5993 ret
= process_all_refs(sctx
,
5994 BTRFS_COMPARE_TREE_DELETED
);
5999 * Now process the inode as if it was new.
6001 sctx
->cur_inode_gen
= left_gen
;
6002 sctx
->cur_inode_new
= 1;
6003 sctx
->cur_inode_deleted
= 0;
6004 sctx
->cur_inode_size
= btrfs_inode_size(
6005 sctx
->left_path
->nodes
[0], left_ii
);
6006 sctx
->cur_inode_mode
= btrfs_inode_mode(
6007 sctx
->left_path
->nodes
[0], left_ii
);
6008 sctx
->cur_inode_rdev
= btrfs_inode_rdev(
6009 sctx
->left_path
->nodes
[0], left_ii
);
6010 ret
= send_create_inode_if_needed(sctx
);
6014 ret
= process_all_refs(sctx
, BTRFS_COMPARE_TREE_NEW
);
6018 * Advance send_progress now as we did not get into
6019 * process_recorded_refs_if_needed in the new_gen case.
6021 sctx
->send_progress
= sctx
->cur_ino
+ 1;
6024 * Now process all extents and xattrs of the inode as if
6025 * they were all new.
6027 ret
= process_all_extents(sctx
);
6030 ret
= process_all_new_xattrs(sctx
);
6034 sctx
->cur_inode_gen
= left_gen
;
6035 sctx
->cur_inode_new
= 0;
6036 sctx
->cur_inode_new_gen
= 0;
6037 sctx
->cur_inode_deleted
= 0;
6038 sctx
->cur_inode_size
= btrfs_inode_size(
6039 sctx
->left_path
->nodes
[0], left_ii
);
6040 sctx
->cur_inode_mode
= btrfs_inode_mode(
6041 sctx
->left_path
->nodes
[0], left_ii
);
6050 * We have to process new refs before deleted refs, but compare_trees gives us
6051 * the new and deleted refs mixed. To fix this, we record the new/deleted refs
6052 * first and later process them in process_recorded_refs.
6053 * For the cur_inode_new_gen case, we skip recording completely because
6054 * changed_inode did already initiate processing of refs. The reason for this is
6055 * that in this case, compare_tree actually compares the refs of 2 different
6056 * inodes. To fix this, process_all_refs is used in changed_inode to handle all
6057 * refs of the right tree as deleted and all refs of the left tree as new.
6059 static int changed_ref(struct send_ctx
*sctx
,
6060 enum btrfs_compare_tree_result result
)
6064 if (sctx
->cur_ino
!= sctx
->cmp_key
->objectid
) {
6065 inconsistent_snapshot_error(sctx
, result
, "reference");
6069 if (!sctx
->cur_inode_new_gen
&&
6070 sctx
->cur_ino
!= BTRFS_FIRST_FREE_OBJECTID
) {
6071 if (result
== BTRFS_COMPARE_TREE_NEW
)
6072 ret
= record_new_ref(sctx
);
6073 else if (result
== BTRFS_COMPARE_TREE_DELETED
)
6074 ret
= record_deleted_ref(sctx
);
6075 else if (result
== BTRFS_COMPARE_TREE_CHANGED
)
6076 ret
= record_changed_ref(sctx
);
6083 * Process new/deleted/changed xattrs. We skip processing in the
6084 * cur_inode_new_gen case because changed_inode did already initiate processing
6085 * of xattrs. The reason is the same as in changed_ref
6087 static int changed_xattr(struct send_ctx
*sctx
,
6088 enum btrfs_compare_tree_result result
)
6092 if (sctx
->cur_ino
!= sctx
->cmp_key
->objectid
) {
6093 inconsistent_snapshot_error(sctx
, result
, "xattr");
6097 if (!sctx
->cur_inode_new_gen
&& !sctx
->cur_inode_deleted
) {
6098 if (result
== BTRFS_COMPARE_TREE_NEW
)
6099 ret
= process_new_xattr(sctx
);
6100 else if (result
== BTRFS_COMPARE_TREE_DELETED
)
6101 ret
= process_deleted_xattr(sctx
);
6102 else if (result
== BTRFS_COMPARE_TREE_CHANGED
)
6103 ret
= process_changed_xattr(sctx
);
6110 * Process new/deleted/changed extents. We skip processing in the
6111 * cur_inode_new_gen case because changed_inode did already initiate processing
6112 * of extents. The reason is the same as in changed_ref
6114 static int changed_extent(struct send_ctx
*sctx
,
6115 enum btrfs_compare_tree_result result
)
6119 if (sctx
->cur_ino
!= sctx
->cmp_key
->objectid
) {
6121 if (result
== BTRFS_COMPARE_TREE_CHANGED
) {
6122 struct extent_buffer
*leaf_l
;
6123 struct extent_buffer
*leaf_r
;
6124 struct btrfs_file_extent_item
*ei_l
;
6125 struct btrfs_file_extent_item
*ei_r
;
6127 leaf_l
= sctx
->left_path
->nodes
[0];
6128 leaf_r
= sctx
->right_path
->nodes
[0];
6129 ei_l
= btrfs_item_ptr(leaf_l
,
6130 sctx
->left_path
->slots
[0],
6131 struct btrfs_file_extent_item
);
6132 ei_r
= btrfs_item_ptr(leaf_r
,
6133 sctx
->right_path
->slots
[0],
6134 struct btrfs_file_extent_item
);
6137 * We may have found an extent item that has changed
6138 * only its disk_bytenr field and the corresponding
6139 * inode item was not updated. This case happens due to
6140 * very specific timings during relocation when a leaf
6141 * that contains file extent items is COWed while
6142 * relocation is ongoing and its in the stage where it
6143 * updates data pointers. So when this happens we can
6144 * safely ignore it since we know it's the same extent,
6145 * but just at different logical and physical locations
6146 * (when an extent is fully replaced with a new one, we
6147 * know the generation number must have changed too,
6148 * since snapshot creation implies committing the current
6149 * transaction, and the inode item must have been updated
6151 * This replacement of the disk_bytenr happens at
6152 * relocation.c:replace_file_extents() through
6153 * relocation.c:btrfs_reloc_cow_block().
6155 if (btrfs_file_extent_generation(leaf_l
, ei_l
) ==
6156 btrfs_file_extent_generation(leaf_r
, ei_r
) &&
6157 btrfs_file_extent_ram_bytes(leaf_l
, ei_l
) ==
6158 btrfs_file_extent_ram_bytes(leaf_r
, ei_r
) &&
6159 btrfs_file_extent_compression(leaf_l
, ei_l
) ==
6160 btrfs_file_extent_compression(leaf_r
, ei_r
) &&
6161 btrfs_file_extent_encryption(leaf_l
, ei_l
) ==
6162 btrfs_file_extent_encryption(leaf_r
, ei_r
) &&
6163 btrfs_file_extent_other_encoding(leaf_l
, ei_l
) ==
6164 btrfs_file_extent_other_encoding(leaf_r
, ei_r
) &&
6165 btrfs_file_extent_type(leaf_l
, ei_l
) ==
6166 btrfs_file_extent_type(leaf_r
, ei_r
) &&
6167 btrfs_file_extent_disk_bytenr(leaf_l
, ei_l
) !=
6168 btrfs_file_extent_disk_bytenr(leaf_r
, ei_r
) &&
6169 btrfs_file_extent_disk_num_bytes(leaf_l
, ei_l
) ==
6170 btrfs_file_extent_disk_num_bytes(leaf_r
, ei_r
) &&
6171 btrfs_file_extent_offset(leaf_l
, ei_l
) ==
6172 btrfs_file_extent_offset(leaf_r
, ei_r
) &&
6173 btrfs_file_extent_num_bytes(leaf_l
, ei_l
) ==
6174 btrfs_file_extent_num_bytes(leaf_r
, ei_r
))
6178 inconsistent_snapshot_error(sctx
, result
, "extent");
6182 if (!sctx
->cur_inode_new_gen
&& !sctx
->cur_inode_deleted
) {
6183 if (result
!= BTRFS_COMPARE_TREE_DELETED
)
6184 ret
= process_extent(sctx
, sctx
->left_path
,
6191 static int dir_changed(struct send_ctx
*sctx
, u64 dir
)
6193 u64 orig_gen
, new_gen
;
6196 ret
= get_inode_info(sctx
->send_root
, dir
, NULL
, &new_gen
, NULL
, NULL
,
6201 ret
= get_inode_info(sctx
->parent_root
, dir
, NULL
, &orig_gen
, NULL
,
6206 return (orig_gen
!= new_gen
) ? 1 : 0;
6209 static int compare_refs(struct send_ctx
*sctx
, struct btrfs_path
*path
,
6210 struct btrfs_key
*key
)
6212 struct btrfs_inode_extref
*extref
;
6213 struct extent_buffer
*leaf
;
6214 u64 dirid
= 0, last_dirid
= 0;
6221 /* Easy case, just check this one dirid */
6222 if (key
->type
== BTRFS_INODE_REF_KEY
) {
6223 dirid
= key
->offset
;
6225 ret
= dir_changed(sctx
, dirid
);
6229 leaf
= path
->nodes
[0];
6230 item_size
= btrfs_item_size_nr(leaf
, path
->slots
[0]);
6231 ptr
= btrfs_item_ptr_offset(leaf
, path
->slots
[0]);
6232 while (cur_offset
< item_size
) {
6233 extref
= (struct btrfs_inode_extref
*)(ptr
+
6235 dirid
= btrfs_inode_extref_parent(leaf
, extref
);
6236 ref_name_len
= btrfs_inode_extref_name_len(leaf
, extref
);
6237 cur_offset
+= ref_name_len
+ sizeof(*extref
);
6238 if (dirid
== last_dirid
)
6240 ret
= dir_changed(sctx
, dirid
);
6250 * Updates compare related fields in sctx and simply forwards to the actual
6251 * changed_xxx functions.
6253 static int changed_cb(struct btrfs_path
*left_path
,
6254 struct btrfs_path
*right_path
,
6255 struct btrfs_key
*key
,
6256 enum btrfs_compare_tree_result result
,
6260 struct send_ctx
*sctx
= ctx
;
6262 if (result
== BTRFS_COMPARE_TREE_SAME
) {
6263 if (key
->type
== BTRFS_INODE_REF_KEY
||
6264 key
->type
== BTRFS_INODE_EXTREF_KEY
) {
6265 ret
= compare_refs(sctx
, left_path
, key
);
6270 } else if (key
->type
== BTRFS_EXTENT_DATA_KEY
) {
6271 return maybe_send_hole(sctx
, left_path
, key
);
6275 result
= BTRFS_COMPARE_TREE_CHANGED
;
6279 sctx
->left_path
= left_path
;
6280 sctx
->right_path
= right_path
;
6281 sctx
->cmp_key
= key
;
6283 ret
= finish_inode_if_needed(sctx
, 0);
6287 /* Ignore non-FS objects */
6288 if (key
->objectid
== BTRFS_FREE_INO_OBJECTID
||
6289 key
->objectid
== BTRFS_FREE_SPACE_OBJECTID
)
6292 if (key
->type
== BTRFS_INODE_ITEM_KEY
)
6293 ret
= changed_inode(sctx
, result
);
6294 else if (key
->type
== BTRFS_INODE_REF_KEY
||
6295 key
->type
== BTRFS_INODE_EXTREF_KEY
)
6296 ret
= changed_ref(sctx
, result
);
6297 else if (key
->type
== BTRFS_XATTR_ITEM_KEY
)
6298 ret
= changed_xattr(sctx
, result
);
6299 else if (key
->type
== BTRFS_EXTENT_DATA_KEY
)
6300 ret
= changed_extent(sctx
, result
);
6306 static int full_send_tree(struct send_ctx
*sctx
)
6309 struct btrfs_root
*send_root
= sctx
->send_root
;
6310 struct btrfs_key key
;
6311 struct btrfs_key found_key
;
6312 struct btrfs_path
*path
;
6313 struct extent_buffer
*eb
;
6316 path
= alloc_path_for_send();
6320 key
.objectid
= BTRFS_FIRST_FREE_OBJECTID
;
6321 key
.type
= BTRFS_INODE_ITEM_KEY
;
6324 ret
= btrfs_search_slot_for_read(send_root
, &key
, path
, 1, 0);
6331 eb
= path
->nodes
[0];
6332 slot
= path
->slots
[0];
6333 btrfs_item_key_to_cpu(eb
, &found_key
, slot
);
6335 ret
= changed_cb(path
, NULL
, &found_key
,
6336 BTRFS_COMPARE_TREE_NEW
, sctx
);
6340 key
.objectid
= found_key
.objectid
;
6341 key
.type
= found_key
.type
;
6342 key
.offset
= found_key
.offset
+ 1;
6344 ret
= btrfs_next_item(send_root
, path
);
6354 ret
= finish_inode_if_needed(sctx
, 1);
6357 btrfs_free_path(path
);
6361 static int send_subvol(struct send_ctx
*sctx
)
6365 if (!(sctx
->flags
& BTRFS_SEND_FLAG_OMIT_STREAM_HEADER
)) {
6366 ret
= send_header(sctx
);
6371 ret
= send_subvol_begin(sctx
);
6375 if (sctx
->parent_root
) {
6376 ret
= btrfs_compare_trees(sctx
->send_root
, sctx
->parent_root
,
6380 ret
= finish_inode_if_needed(sctx
, 1);
6384 ret
= full_send_tree(sctx
);
6390 free_recorded_refs(sctx
);
6395 * If orphan cleanup did remove any orphans from a root, it means the tree
6396 * was modified and therefore the commit root is not the same as the current
6397 * root anymore. This is a problem, because send uses the commit root and
6398 * therefore can see inode items that don't exist in the current root anymore,
6399 * and for example make calls to btrfs_iget, which will do tree lookups based
6400 * on the current root and not on the commit root. Those lookups will fail,
6401 * returning a -ESTALE error, and making send fail with that error. So make
6402 * sure a send does not see any orphans we have just removed, and that it will
6403 * see the same inodes regardless of whether a transaction commit happened
6404 * before it started (meaning that the commit root will be the same as the
6405 * current root) or not.
6407 static int ensure_commit_roots_uptodate(struct send_ctx
*sctx
)
6410 struct btrfs_trans_handle
*trans
= NULL
;
6413 if (sctx
->parent_root
&&
6414 sctx
->parent_root
->node
!= sctx
->parent_root
->commit_root
)
6417 for (i
= 0; i
< sctx
->clone_roots_cnt
; i
++)
6418 if (sctx
->clone_roots
[i
].root
->node
!=
6419 sctx
->clone_roots
[i
].root
->commit_root
)
6423 return btrfs_end_transaction(trans
);
6428 /* Use any root, all fs roots will get their commit roots updated. */
6430 trans
= btrfs_join_transaction(sctx
->send_root
);
6432 return PTR_ERR(trans
);
6436 return btrfs_commit_transaction(trans
);
6439 static void btrfs_root_dec_send_in_progress(struct btrfs_root
* root
)
6441 spin_lock(&root
->root_item_lock
);
6442 root
->send_in_progress
--;
6444 * Not much left to do, we don't know why it's unbalanced and
6445 * can't blindly reset it to 0.
6447 if (root
->send_in_progress
< 0)
6448 btrfs_err(root
->fs_info
,
6449 "send_in_progres unbalanced %d root %llu",
6450 root
->send_in_progress
, root
->root_key
.objectid
);
6451 spin_unlock(&root
->root_item_lock
);
6454 long btrfs_ioctl_send(struct file
*mnt_file
, struct btrfs_ioctl_send_args
*arg
)
6457 struct btrfs_root
*send_root
= BTRFS_I(file_inode(mnt_file
))->root
;
6458 struct btrfs_fs_info
*fs_info
= send_root
->fs_info
;
6459 struct btrfs_root
*clone_root
;
6460 struct btrfs_key key
;
6461 struct send_ctx
*sctx
= NULL
;
6463 u64
*clone_sources_tmp
= NULL
;
6464 int clone_sources_to_rollback
= 0;
6465 unsigned alloc_size
;
6466 int sort_clone_roots
= 0;
6469 if (!capable(CAP_SYS_ADMIN
))
6473 * The subvolume must remain read-only during send, protect against
6474 * making it RW. This also protects against deletion.
6476 spin_lock(&send_root
->root_item_lock
);
6477 send_root
->send_in_progress
++;
6478 spin_unlock(&send_root
->root_item_lock
);
6481 * This is done when we lookup the root, it should already be complete
6482 * by the time we get here.
6484 WARN_ON(send_root
->orphan_cleanup_state
!= ORPHAN_CLEANUP_DONE
);
6487 * Userspace tools do the checks and warn the user if it's
6490 if (!btrfs_root_readonly(send_root
)) {
6496 * Check that we don't overflow at later allocations, we request
6497 * clone_sources_count + 1 items, and compare to unsigned long inside
6500 if (arg
->clone_sources_count
>
6501 ULONG_MAX
/ sizeof(struct clone_root
) - 1) {
6506 if (!access_ok(VERIFY_READ
, arg
->clone_sources
,
6507 sizeof(*arg
->clone_sources
) *
6508 arg
->clone_sources_count
)) {
6513 if (arg
->flags
& ~BTRFS_SEND_FLAG_MASK
) {
6518 sctx
= kzalloc(sizeof(struct send_ctx
), GFP_KERNEL
);
6524 INIT_LIST_HEAD(&sctx
->new_refs
);
6525 INIT_LIST_HEAD(&sctx
->deleted_refs
);
6526 INIT_RADIX_TREE(&sctx
->name_cache
, GFP_KERNEL
);
6527 INIT_LIST_HEAD(&sctx
->name_cache_list
);
6529 sctx
->flags
= arg
->flags
;
6531 sctx
->send_filp
= fget(arg
->send_fd
);
6532 if (!sctx
->send_filp
) {
6537 sctx
->send_root
= send_root
;
6539 * Unlikely but possible, if the subvolume is marked for deletion but
6540 * is slow to remove the directory entry, send can still be started
6542 if (btrfs_root_dead(sctx
->send_root
)) {
6547 sctx
->clone_roots_cnt
= arg
->clone_sources_count
;
6549 sctx
->send_max_size
= BTRFS_SEND_BUF_SIZE
;
6550 sctx
->send_buf
= kvmalloc(sctx
->send_max_size
, GFP_KERNEL
);
6551 if (!sctx
->send_buf
) {
6556 sctx
->read_buf
= kvmalloc(BTRFS_SEND_READ_SIZE
, GFP_KERNEL
);
6557 if (!sctx
->read_buf
) {
6562 sctx
->pending_dir_moves
= RB_ROOT
;
6563 sctx
->waiting_dir_moves
= RB_ROOT
;
6564 sctx
->orphan_dirs
= RB_ROOT
;
6566 alloc_size
= sizeof(struct clone_root
) * (arg
->clone_sources_count
+ 1);
6568 sctx
->clone_roots
= kzalloc(alloc_size
, GFP_KERNEL
);
6569 if (!sctx
->clone_roots
) {
6574 alloc_size
= arg
->clone_sources_count
* sizeof(*arg
->clone_sources
);
6576 if (arg
->clone_sources_count
) {
6577 clone_sources_tmp
= kvmalloc(alloc_size
, GFP_KERNEL
);
6578 if (!clone_sources_tmp
) {
6583 ret
= copy_from_user(clone_sources_tmp
, arg
->clone_sources
,
6590 for (i
= 0; i
< arg
->clone_sources_count
; i
++) {
6591 key
.objectid
= clone_sources_tmp
[i
];
6592 key
.type
= BTRFS_ROOT_ITEM_KEY
;
6593 key
.offset
= (u64
)-1;
6595 index
= srcu_read_lock(&fs_info
->subvol_srcu
);
6597 clone_root
= btrfs_read_fs_root_no_name(fs_info
, &key
);
6598 if (IS_ERR(clone_root
)) {
6599 srcu_read_unlock(&fs_info
->subvol_srcu
, index
);
6600 ret
= PTR_ERR(clone_root
);
6603 spin_lock(&clone_root
->root_item_lock
);
6604 if (!btrfs_root_readonly(clone_root
) ||
6605 btrfs_root_dead(clone_root
)) {
6606 spin_unlock(&clone_root
->root_item_lock
);
6607 srcu_read_unlock(&fs_info
->subvol_srcu
, index
);
6611 clone_root
->send_in_progress
++;
6612 spin_unlock(&clone_root
->root_item_lock
);
6613 srcu_read_unlock(&fs_info
->subvol_srcu
, index
);
6615 sctx
->clone_roots
[i
].root
= clone_root
;
6616 clone_sources_to_rollback
= i
+ 1;
6618 kvfree(clone_sources_tmp
);
6619 clone_sources_tmp
= NULL
;
6622 if (arg
->parent_root
) {
6623 key
.objectid
= arg
->parent_root
;
6624 key
.type
= BTRFS_ROOT_ITEM_KEY
;
6625 key
.offset
= (u64
)-1;
6627 index
= srcu_read_lock(&fs_info
->subvol_srcu
);
6629 sctx
->parent_root
= btrfs_read_fs_root_no_name(fs_info
, &key
);
6630 if (IS_ERR(sctx
->parent_root
)) {
6631 srcu_read_unlock(&fs_info
->subvol_srcu
, index
);
6632 ret
= PTR_ERR(sctx
->parent_root
);
6636 spin_lock(&sctx
->parent_root
->root_item_lock
);
6637 sctx
->parent_root
->send_in_progress
++;
6638 if (!btrfs_root_readonly(sctx
->parent_root
) ||
6639 btrfs_root_dead(sctx
->parent_root
)) {
6640 spin_unlock(&sctx
->parent_root
->root_item_lock
);
6641 srcu_read_unlock(&fs_info
->subvol_srcu
, index
);
6645 spin_unlock(&sctx
->parent_root
->root_item_lock
);
6647 srcu_read_unlock(&fs_info
->subvol_srcu
, index
);
6651 * Clones from send_root are allowed, but only if the clone source
6652 * is behind the current send position. This is checked while searching
6653 * for possible clone sources.
6655 sctx
->clone_roots
[sctx
->clone_roots_cnt
++].root
= sctx
->send_root
;
6657 /* We do a bsearch later */
6658 sort(sctx
->clone_roots
, sctx
->clone_roots_cnt
,
6659 sizeof(*sctx
->clone_roots
), __clone_root_cmp_sort
,
6661 sort_clone_roots
= 1;
6663 ret
= ensure_commit_roots_uptodate(sctx
);
6667 current
->journal_info
= BTRFS_SEND_TRANS_STUB
;
6668 ret
= send_subvol(sctx
);
6669 current
->journal_info
= NULL
;
6673 if (!(sctx
->flags
& BTRFS_SEND_FLAG_OMIT_END_CMD
)) {
6674 ret
= begin_cmd(sctx
, BTRFS_SEND_C_END
);
6677 ret
= send_cmd(sctx
);
6683 WARN_ON(sctx
&& !ret
&& !RB_EMPTY_ROOT(&sctx
->pending_dir_moves
));
6684 while (sctx
&& !RB_EMPTY_ROOT(&sctx
->pending_dir_moves
)) {
6686 struct pending_dir_move
*pm
;
6688 n
= rb_first(&sctx
->pending_dir_moves
);
6689 pm
= rb_entry(n
, struct pending_dir_move
, node
);
6690 while (!list_empty(&pm
->list
)) {
6691 struct pending_dir_move
*pm2
;
6693 pm2
= list_first_entry(&pm
->list
,
6694 struct pending_dir_move
, list
);
6695 free_pending_move(sctx
, pm2
);
6697 free_pending_move(sctx
, pm
);
6700 WARN_ON(sctx
&& !ret
&& !RB_EMPTY_ROOT(&sctx
->waiting_dir_moves
));
6701 while (sctx
&& !RB_EMPTY_ROOT(&sctx
->waiting_dir_moves
)) {
6703 struct waiting_dir_move
*dm
;
6705 n
= rb_first(&sctx
->waiting_dir_moves
);
6706 dm
= rb_entry(n
, struct waiting_dir_move
, node
);
6707 rb_erase(&dm
->node
, &sctx
->waiting_dir_moves
);
6711 WARN_ON(sctx
&& !ret
&& !RB_EMPTY_ROOT(&sctx
->orphan_dirs
));
6712 while (sctx
&& !RB_EMPTY_ROOT(&sctx
->orphan_dirs
)) {
6714 struct orphan_dir_info
*odi
;
6716 n
= rb_first(&sctx
->orphan_dirs
);
6717 odi
= rb_entry(n
, struct orphan_dir_info
, node
);
6718 free_orphan_dir_info(sctx
, odi
);
6721 if (sort_clone_roots
) {
6722 for (i
= 0; i
< sctx
->clone_roots_cnt
; i
++)
6723 btrfs_root_dec_send_in_progress(
6724 sctx
->clone_roots
[i
].root
);
6726 for (i
= 0; sctx
&& i
< clone_sources_to_rollback
; i
++)
6727 btrfs_root_dec_send_in_progress(
6728 sctx
->clone_roots
[i
].root
);
6730 btrfs_root_dec_send_in_progress(send_root
);
6732 if (sctx
&& !IS_ERR_OR_NULL(sctx
->parent_root
))
6733 btrfs_root_dec_send_in_progress(sctx
->parent_root
);
6735 kvfree(clone_sources_tmp
);
6738 if (sctx
->send_filp
)
6739 fput(sctx
->send_filp
);
6741 kvfree(sctx
->clone_roots
);
6742 kvfree(sctx
->send_buf
);
6743 kvfree(sctx
->read_buf
);
6745 name_cache_free(sctx
);