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>
35 #include "btrfs_inode.h"
36 #include "transaction.h"
38 static int g_verbose
= 0;
40 #define verbose_printk(...) if (g_verbose) printk(__VA_ARGS__)
43 * A fs_path is a helper to dynamically build path names with unknown size.
44 * It reallocates the internal buffer on demand.
45 * It allows fast adding of path elements on the right side (normal path) and
46 * fast adding to the left side (reversed path). A reversed path can also be
47 * unreversed if needed.
56 unsigned short buf_len
:15;
57 unsigned short reversed
:1;
61 * Average path length does not exceed 200 bytes, we'll have
62 * better packing in the slab and higher chance to satisfy
63 * a allocation later during send.
68 #define FS_PATH_INLINE_SIZE \
69 (sizeof(struct fs_path) - offsetof(struct fs_path, inline_buf))
72 /* reused for each extent */
74 struct btrfs_root
*root
;
81 #define SEND_CTX_MAX_NAME_CACHE_SIZE 128
82 #define SEND_CTX_NAME_CACHE_CLEAN_SIZE (SEND_CTX_MAX_NAME_CACHE_SIZE * 2)
85 struct file
*send_filp
;
91 u64 cmd_send_size
[BTRFS_SEND_C_MAX
+ 1];
92 u64 flags
; /* 'flags' member of btrfs_ioctl_send_args is u64 */
94 struct btrfs_root
*send_root
;
95 struct btrfs_root
*parent_root
;
96 struct clone_root
*clone_roots
;
99 /* current state of the compare_tree call */
100 struct btrfs_path
*left_path
;
101 struct btrfs_path
*right_path
;
102 struct btrfs_key
*cmp_key
;
105 * infos of the currently processed inode. In case of deleted inodes,
106 * these are the values from the deleted inode.
111 int cur_inode_new_gen
;
112 int cur_inode_deleted
;
116 u64 cur_inode_last_extent
;
120 struct list_head new_refs
;
121 struct list_head deleted_refs
;
123 struct radix_tree_root name_cache
;
124 struct list_head name_cache_list
;
127 struct file_ra_state ra
;
132 * We process inodes by their increasing order, so if before an
133 * incremental send we reverse the parent/child relationship of
134 * directories such that a directory with a lower inode number was
135 * the parent of a directory with a higher inode number, and the one
136 * becoming the new parent got renamed too, we can't rename/move the
137 * directory with lower inode number when we finish processing it - we
138 * must process the directory with higher inode number first, then
139 * rename/move it and then rename/move the directory with lower inode
140 * number. Example follows.
142 * Tree state when the first send was performed:
154 * Tree state when the second (incremental) send is performed:
163 * The sequence of steps that lead to the second state was:
165 * mv /a/b/c/d /a/b/c2/d2
166 * mv /a/b/c /a/b/c2/d2/cc
168 * "c" has lower inode number, but we can't move it (2nd mv operation)
169 * before we move "d", which has higher inode number.
171 * So we just memorize which move/rename operations must be performed
172 * later when their respective parent is processed and moved/renamed.
175 /* Indexed by parent directory inode number. */
176 struct rb_root pending_dir_moves
;
179 * Reverse index, indexed by the inode number of a directory that
180 * is waiting for the move/rename of its immediate parent before its
181 * own move/rename can be performed.
183 struct rb_root waiting_dir_moves
;
186 * A directory that is going to be rm'ed might have a child directory
187 * which is in the pending directory moves index above. In this case,
188 * the directory can only be removed after the move/rename of its child
189 * is performed. Example:
209 * Sequence of steps that lead to the send snapshot:
210 * rm -f /a/b/c/foo.txt
212 * mv /a/b/c/x /a/b/YY
215 * When the child is processed, its move/rename is delayed until its
216 * parent is processed (as explained above), but all other operations
217 * like update utimes, chown, chgrp, etc, are performed and the paths
218 * that it uses for those operations must use the orphanized name of
219 * its parent (the directory we're going to rm later), so we need to
220 * memorize that name.
222 * Indexed by the inode number of the directory to be deleted.
224 struct rb_root orphan_dirs
;
227 struct pending_dir_move
{
229 struct list_head list
;
234 struct list_head update_refs
;
237 struct waiting_dir_move
{
241 * There might be some directory that could not be removed because it
242 * was waiting for this directory inode to be moved first. Therefore
243 * after this directory is moved, we can try to rmdir the ino rmdir_ino.
249 struct orphan_dir_info
{
255 struct name_cache_entry
{
256 struct list_head list
;
258 * radix_tree has only 32bit entries but we need to handle 64bit inums.
259 * We use the lower 32bit of the 64bit inum to store it in the tree. If
260 * more then one inum would fall into the same entry, we use radix_list
261 * to store the additional entries. radix_list is also used to store
262 * entries where two entries have the same inum but different
265 struct list_head radix_list
;
271 int need_later_update
;
276 static int is_waiting_for_move(struct send_ctx
*sctx
, u64 ino
);
278 static struct waiting_dir_move
*
279 get_waiting_dir_move(struct send_ctx
*sctx
, u64 ino
);
281 static int is_waiting_for_rm(struct send_ctx
*sctx
, u64 dir_ino
);
283 static int need_send_hole(struct send_ctx
*sctx
)
285 return (sctx
->parent_root
&& !sctx
->cur_inode_new
&&
286 !sctx
->cur_inode_new_gen
&& !sctx
->cur_inode_deleted
&&
287 S_ISREG(sctx
->cur_inode_mode
));
290 static void fs_path_reset(struct fs_path
*p
)
293 p
->start
= p
->buf
+ p
->buf_len
- 1;
303 static struct fs_path
*fs_path_alloc(void)
307 p
= kmalloc(sizeof(*p
), GFP_NOFS
);
311 p
->buf
= p
->inline_buf
;
312 p
->buf_len
= FS_PATH_INLINE_SIZE
;
317 static struct fs_path
*fs_path_alloc_reversed(void)
329 static void fs_path_free(struct fs_path
*p
)
333 if (p
->buf
!= p
->inline_buf
)
338 static int fs_path_len(struct fs_path
*p
)
340 return p
->end
- p
->start
;
343 static int fs_path_ensure_buf(struct fs_path
*p
, int len
)
351 if (p
->buf_len
>= len
)
354 if (len
> PATH_MAX
) {
359 path_len
= p
->end
- p
->start
;
360 old_buf_len
= p
->buf_len
;
363 * First time the inline_buf does not suffice
365 if (p
->buf
== p
->inline_buf
) {
366 tmp_buf
= kmalloc(len
, GFP_NOFS
);
368 memcpy(tmp_buf
, p
->buf
, old_buf_len
);
370 tmp_buf
= krealloc(p
->buf
, len
, GFP_NOFS
);
376 * The real size of the buffer is bigger, this will let the fast path
377 * happen most of the time
379 p
->buf_len
= ksize(p
->buf
);
382 tmp_buf
= p
->buf
+ old_buf_len
- path_len
- 1;
383 p
->end
= p
->buf
+ p
->buf_len
- 1;
384 p
->start
= p
->end
- path_len
;
385 memmove(p
->start
, tmp_buf
, path_len
+ 1);
388 p
->end
= p
->start
+ path_len
;
393 static int fs_path_prepare_for_add(struct fs_path
*p
, int name_len
,
399 new_len
= p
->end
- p
->start
+ name_len
;
400 if (p
->start
!= p
->end
)
402 ret
= fs_path_ensure_buf(p
, new_len
);
407 if (p
->start
!= p
->end
)
409 p
->start
-= name_len
;
410 *prepared
= p
->start
;
412 if (p
->start
!= p
->end
)
423 static int fs_path_add(struct fs_path
*p
, const char *name
, int name_len
)
428 ret
= fs_path_prepare_for_add(p
, name_len
, &prepared
);
431 memcpy(prepared
, name
, name_len
);
437 static int fs_path_add_path(struct fs_path
*p
, struct fs_path
*p2
)
442 ret
= fs_path_prepare_for_add(p
, p2
->end
- p2
->start
, &prepared
);
445 memcpy(prepared
, p2
->start
, p2
->end
- p2
->start
);
451 static int fs_path_add_from_extent_buffer(struct fs_path
*p
,
452 struct extent_buffer
*eb
,
453 unsigned long off
, int len
)
458 ret
= fs_path_prepare_for_add(p
, len
, &prepared
);
462 read_extent_buffer(eb
, prepared
, off
, len
);
468 static int fs_path_copy(struct fs_path
*p
, struct fs_path
*from
)
472 p
->reversed
= from
->reversed
;
475 ret
= fs_path_add_path(p
, from
);
481 static void fs_path_unreverse(struct fs_path
*p
)
490 len
= p
->end
- p
->start
;
492 p
->end
= p
->start
+ len
;
493 memmove(p
->start
, tmp
, len
+ 1);
497 static struct btrfs_path
*alloc_path_for_send(void)
499 struct btrfs_path
*path
;
501 path
= btrfs_alloc_path();
504 path
->search_commit_root
= 1;
505 path
->skip_locking
= 1;
506 path
->need_commit_sem
= 1;
510 static int write_buf(struct file
*filp
, const void *buf
, u32 len
, loff_t
*off
)
520 ret
= vfs_write(filp
, (__force
const char __user
*)buf
+ pos
,
522 /* TODO handle that correctly */
523 /*if (ret == -ERESTARTSYS) {
542 static int tlv_put(struct send_ctx
*sctx
, u16 attr
, const void *data
, int len
)
544 struct btrfs_tlv_header
*hdr
;
545 int total_len
= sizeof(*hdr
) + len
;
546 int left
= sctx
->send_max_size
- sctx
->send_size
;
548 if (unlikely(left
< total_len
))
551 hdr
= (struct btrfs_tlv_header
*) (sctx
->send_buf
+ sctx
->send_size
);
552 hdr
->tlv_type
= cpu_to_le16(attr
);
553 hdr
->tlv_len
= cpu_to_le16(len
);
554 memcpy(hdr
+ 1, data
, len
);
555 sctx
->send_size
+= total_len
;
560 #define TLV_PUT_DEFINE_INT(bits) \
561 static int tlv_put_u##bits(struct send_ctx *sctx, \
562 u##bits attr, u##bits value) \
564 __le##bits __tmp = cpu_to_le##bits(value); \
565 return tlv_put(sctx, attr, &__tmp, sizeof(__tmp)); \
568 TLV_PUT_DEFINE_INT(64)
570 static int tlv_put_string(struct send_ctx
*sctx
, u16 attr
,
571 const char *str
, int len
)
575 return tlv_put(sctx
, attr
, str
, len
);
578 static int tlv_put_uuid(struct send_ctx
*sctx
, u16 attr
,
581 return tlv_put(sctx
, attr
, uuid
, BTRFS_UUID_SIZE
);
584 static int tlv_put_btrfs_timespec(struct send_ctx
*sctx
, u16 attr
,
585 struct extent_buffer
*eb
,
586 struct btrfs_timespec
*ts
)
588 struct btrfs_timespec bts
;
589 read_extent_buffer(eb
, &bts
, (unsigned long)ts
, sizeof(bts
));
590 return tlv_put(sctx
, attr
, &bts
, sizeof(bts
));
594 #define TLV_PUT(sctx, attrtype, attrlen, data) \
596 ret = tlv_put(sctx, attrtype, attrlen, data); \
598 goto tlv_put_failure; \
601 #define TLV_PUT_INT(sctx, attrtype, bits, value) \
603 ret = tlv_put_u##bits(sctx, attrtype, value); \
605 goto tlv_put_failure; \
608 #define TLV_PUT_U8(sctx, attrtype, data) TLV_PUT_INT(sctx, attrtype, 8, data)
609 #define TLV_PUT_U16(sctx, attrtype, data) TLV_PUT_INT(sctx, attrtype, 16, data)
610 #define TLV_PUT_U32(sctx, attrtype, data) TLV_PUT_INT(sctx, attrtype, 32, data)
611 #define TLV_PUT_U64(sctx, attrtype, data) TLV_PUT_INT(sctx, attrtype, 64, data)
612 #define TLV_PUT_STRING(sctx, attrtype, str, len) \
614 ret = tlv_put_string(sctx, attrtype, str, len); \
616 goto tlv_put_failure; \
618 #define TLV_PUT_PATH(sctx, attrtype, p) \
620 ret = tlv_put_string(sctx, attrtype, p->start, \
621 p->end - p->start); \
623 goto tlv_put_failure; \
625 #define TLV_PUT_UUID(sctx, attrtype, uuid) \
627 ret = tlv_put_uuid(sctx, attrtype, uuid); \
629 goto tlv_put_failure; \
631 #define TLV_PUT_BTRFS_TIMESPEC(sctx, attrtype, eb, ts) \
633 ret = tlv_put_btrfs_timespec(sctx, attrtype, eb, ts); \
635 goto tlv_put_failure; \
638 static int send_header(struct send_ctx
*sctx
)
640 struct btrfs_stream_header hdr
;
642 strcpy(hdr
.magic
, BTRFS_SEND_STREAM_MAGIC
);
643 hdr
.version
= cpu_to_le32(BTRFS_SEND_STREAM_VERSION
);
645 return write_buf(sctx
->send_filp
, &hdr
, sizeof(hdr
),
650 * For each command/item we want to send to userspace, we call this function.
652 static int begin_cmd(struct send_ctx
*sctx
, int cmd
)
654 struct btrfs_cmd_header
*hdr
;
656 if (WARN_ON(!sctx
->send_buf
))
659 BUG_ON(sctx
->send_size
);
661 sctx
->send_size
+= sizeof(*hdr
);
662 hdr
= (struct btrfs_cmd_header
*)sctx
->send_buf
;
663 hdr
->cmd
= cpu_to_le16(cmd
);
668 static int send_cmd(struct send_ctx
*sctx
)
671 struct btrfs_cmd_header
*hdr
;
674 hdr
= (struct btrfs_cmd_header
*)sctx
->send_buf
;
675 hdr
->len
= cpu_to_le32(sctx
->send_size
- sizeof(*hdr
));
678 crc
= btrfs_crc32c(0, (unsigned char *)sctx
->send_buf
, sctx
->send_size
);
679 hdr
->crc
= cpu_to_le32(crc
);
681 ret
= write_buf(sctx
->send_filp
, sctx
->send_buf
, sctx
->send_size
,
684 sctx
->total_send_size
+= sctx
->send_size
;
685 sctx
->cmd_send_size
[le16_to_cpu(hdr
->cmd
)] += sctx
->send_size
;
692 * Sends a move instruction to user space
694 static int send_rename(struct send_ctx
*sctx
,
695 struct fs_path
*from
, struct fs_path
*to
)
699 verbose_printk("btrfs: send_rename %s -> %s\n", from
->start
, to
->start
);
701 ret
= begin_cmd(sctx
, BTRFS_SEND_C_RENAME
);
705 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, from
);
706 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH_TO
, to
);
708 ret
= send_cmd(sctx
);
716 * Sends a link instruction to user space
718 static int send_link(struct send_ctx
*sctx
,
719 struct fs_path
*path
, struct fs_path
*lnk
)
723 verbose_printk("btrfs: send_link %s -> %s\n", path
->start
, lnk
->start
);
725 ret
= begin_cmd(sctx
, BTRFS_SEND_C_LINK
);
729 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, path
);
730 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH_LINK
, lnk
);
732 ret
= send_cmd(sctx
);
740 * Sends an unlink instruction to user space
742 static int send_unlink(struct send_ctx
*sctx
, struct fs_path
*path
)
746 verbose_printk("btrfs: send_unlink %s\n", path
->start
);
748 ret
= begin_cmd(sctx
, BTRFS_SEND_C_UNLINK
);
752 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, path
);
754 ret
= send_cmd(sctx
);
762 * Sends a rmdir instruction to user space
764 static int send_rmdir(struct send_ctx
*sctx
, struct fs_path
*path
)
768 verbose_printk("btrfs: send_rmdir %s\n", path
->start
);
770 ret
= begin_cmd(sctx
, BTRFS_SEND_C_RMDIR
);
774 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, path
);
776 ret
= send_cmd(sctx
);
784 * Helper function to retrieve some fields from an inode item.
786 static int __get_inode_info(struct btrfs_root
*root
, struct btrfs_path
*path
,
787 u64 ino
, u64
*size
, u64
*gen
, u64
*mode
, u64
*uid
,
791 struct btrfs_inode_item
*ii
;
792 struct btrfs_key key
;
795 key
.type
= BTRFS_INODE_ITEM_KEY
;
797 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
804 ii
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
805 struct btrfs_inode_item
);
807 *size
= btrfs_inode_size(path
->nodes
[0], ii
);
809 *gen
= btrfs_inode_generation(path
->nodes
[0], ii
);
811 *mode
= btrfs_inode_mode(path
->nodes
[0], ii
);
813 *uid
= btrfs_inode_uid(path
->nodes
[0], ii
);
815 *gid
= btrfs_inode_gid(path
->nodes
[0], ii
);
817 *rdev
= btrfs_inode_rdev(path
->nodes
[0], ii
);
822 static int get_inode_info(struct btrfs_root
*root
,
823 u64 ino
, u64
*size
, u64
*gen
,
824 u64
*mode
, u64
*uid
, u64
*gid
,
827 struct btrfs_path
*path
;
830 path
= alloc_path_for_send();
833 ret
= __get_inode_info(root
, path
, ino
, size
, gen
, mode
, uid
, gid
,
835 btrfs_free_path(path
);
839 typedef int (*iterate_inode_ref_t
)(int num
, u64 dir
, int index
,
844 * Helper function to iterate the entries in ONE btrfs_inode_ref or
845 * btrfs_inode_extref.
846 * The iterate callback may return a non zero value to stop iteration. This can
847 * be a negative value for error codes or 1 to simply stop it.
849 * path must point to the INODE_REF or INODE_EXTREF when called.
851 static int iterate_inode_ref(struct btrfs_root
*root
, struct btrfs_path
*path
,
852 struct btrfs_key
*found_key
, int resolve
,
853 iterate_inode_ref_t iterate
, void *ctx
)
855 struct extent_buffer
*eb
= path
->nodes
[0];
856 struct btrfs_item
*item
;
857 struct btrfs_inode_ref
*iref
;
858 struct btrfs_inode_extref
*extref
;
859 struct btrfs_path
*tmp_path
;
863 int slot
= path
->slots
[0];
870 unsigned long name_off
;
871 unsigned long elem_size
;
874 p
= fs_path_alloc_reversed();
878 tmp_path
= alloc_path_for_send();
885 if (found_key
->type
== BTRFS_INODE_REF_KEY
) {
886 ptr
= (unsigned long)btrfs_item_ptr(eb
, slot
,
887 struct btrfs_inode_ref
);
888 item
= btrfs_item_nr(slot
);
889 total
= btrfs_item_size(eb
, item
);
890 elem_size
= sizeof(*iref
);
892 ptr
= btrfs_item_ptr_offset(eb
, slot
);
893 total
= btrfs_item_size_nr(eb
, slot
);
894 elem_size
= sizeof(*extref
);
897 while (cur
< total
) {
900 if (found_key
->type
== BTRFS_INODE_REF_KEY
) {
901 iref
= (struct btrfs_inode_ref
*)(ptr
+ cur
);
902 name_len
= btrfs_inode_ref_name_len(eb
, iref
);
903 name_off
= (unsigned long)(iref
+ 1);
904 index
= btrfs_inode_ref_index(eb
, iref
);
905 dir
= found_key
->offset
;
907 extref
= (struct btrfs_inode_extref
*)(ptr
+ cur
);
908 name_len
= btrfs_inode_extref_name_len(eb
, extref
);
909 name_off
= (unsigned long)&extref
->name
;
910 index
= btrfs_inode_extref_index(eb
, extref
);
911 dir
= btrfs_inode_extref_parent(eb
, extref
);
915 start
= btrfs_ref_to_path(root
, tmp_path
, name_len
,
919 ret
= PTR_ERR(start
);
922 if (start
< p
->buf
) {
923 /* overflow , try again with larger buffer */
924 ret
= fs_path_ensure_buf(p
,
925 p
->buf_len
+ p
->buf
- start
);
928 start
= btrfs_ref_to_path(root
, tmp_path
,
933 ret
= PTR_ERR(start
);
936 BUG_ON(start
< p
->buf
);
940 ret
= fs_path_add_from_extent_buffer(p
, eb
, name_off
,
946 cur
+= elem_size
+ name_len
;
947 ret
= iterate(num
, dir
, index
, p
, ctx
);
954 btrfs_free_path(tmp_path
);
959 typedef int (*iterate_dir_item_t
)(int num
, struct btrfs_key
*di_key
,
960 const char *name
, int name_len
,
961 const char *data
, int data_len
,
965 * Helper function to iterate the entries in ONE btrfs_dir_item.
966 * The iterate callback may return a non zero value to stop iteration. This can
967 * be a negative value for error codes or 1 to simply stop it.
969 * path must point to the dir item when called.
971 static int iterate_dir_item(struct btrfs_root
*root
, struct btrfs_path
*path
,
972 struct btrfs_key
*found_key
,
973 iterate_dir_item_t iterate
, void *ctx
)
976 struct extent_buffer
*eb
;
977 struct btrfs_item
*item
;
978 struct btrfs_dir_item
*di
;
979 struct btrfs_key di_key
;
992 * Start with a small buffer (1 page). If later we end up needing more
993 * space, which can happen for xattrs on a fs with a leaf size greater
994 * then the page size, attempt to increase the buffer. Typically xattr
998 buf
= kmalloc(buf_len
, GFP_NOFS
);
1004 eb
= path
->nodes
[0];
1005 slot
= path
->slots
[0];
1006 item
= btrfs_item_nr(slot
);
1007 di
= btrfs_item_ptr(eb
, slot
, struct btrfs_dir_item
);
1010 total
= btrfs_item_size(eb
, item
);
1013 while (cur
< total
) {
1014 name_len
= btrfs_dir_name_len(eb
, di
);
1015 data_len
= btrfs_dir_data_len(eb
, di
);
1016 type
= btrfs_dir_type(eb
, di
);
1017 btrfs_dir_item_key_to_cpu(eb
, di
, &di_key
);
1019 if (type
== BTRFS_FT_XATTR
) {
1020 if (name_len
> XATTR_NAME_MAX
) {
1021 ret
= -ENAMETOOLONG
;
1024 if (name_len
+ data_len
> BTRFS_MAX_XATTR_SIZE(root
)) {
1032 if (name_len
+ data_len
> PATH_MAX
) {
1033 ret
= -ENAMETOOLONG
;
1038 if (name_len
+ data_len
> buf_len
) {
1039 buf_len
= name_len
+ data_len
;
1040 if (is_vmalloc_addr(buf
)) {
1044 char *tmp
= krealloc(buf
, buf_len
,
1045 GFP_NOFS
| __GFP_NOWARN
);
1052 buf
= vmalloc(buf_len
);
1060 read_extent_buffer(eb
, buf
, (unsigned long)(di
+ 1),
1061 name_len
+ data_len
);
1063 len
= sizeof(*di
) + name_len
+ data_len
;
1064 di
= (struct btrfs_dir_item
*)((char *)di
+ len
);
1067 ret
= iterate(num
, &di_key
, buf
, name_len
, buf
+ name_len
,
1068 data_len
, type
, ctx
);
1084 static int __copy_first_ref(int num
, u64 dir
, int index
,
1085 struct fs_path
*p
, void *ctx
)
1088 struct fs_path
*pt
= ctx
;
1090 ret
= fs_path_copy(pt
, p
);
1094 /* we want the first only */
1099 * Retrieve the first path of an inode. If an inode has more then one
1100 * ref/hardlink, this is ignored.
1102 static int get_inode_path(struct btrfs_root
*root
,
1103 u64 ino
, struct fs_path
*path
)
1106 struct btrfs_key key
, found_key
;
1107 struct btrfs_path
*p
;
1109 p
= alloc_path_for_send();
1113 fs_path_reset(path
);
1116 key
.type
= BTRFS_INODE_REF_KEY
;
1119 ret
= btrfs_search_slot_for_read(root
, &key
, p
, 1, 0);
1126 btrfs_item_key_to_cpu(p
->nodes
[0], &found_key
, p
->slots
[0]);
1127 if (found_key
.objectid
!= ino
||
1128 (found_key
.type
!= BTRFS_INODE_REF_KEY
&&
1129 found_key
.type
!= BTRFS_INODE_EXTREF_KEY
)) {
1134 ret
= iterate_inode_ref(root
, p
, &found_key
, 1,
1135 __copy_first_ref
, path
);
1145 struct backref_ctx
{
1146 struct send_ctx
*sctx
;
1148 struct btrfs_path
*path
;
1149 /* number of total found references */
1153 * used for clones found in send_root. clones found behind cur_objectid
1154 * and cur_offset are not considered as allowed clones.
1159 /* may be truncated in case it's the last extent in a file */
1162 /* data offset in the file extent item */
1165 /* Just to check for bugs in backref resolving */
1169 static int __clone_root_cmp_bsearch(const void *key
, const void *elt
)
1171 u64 root
= (u64
)(uintptr_t)key
;
1172 struct clone_root
*cr
= (struct clone_root
*)elt
;
1174 if (root
< cr
->root
->objectid
)
1176 if (root
> cr
->root
->objectid
)
1181 static int __clone_root_cmp_sort(const void *e1
, const void *e2
)
1183 struct clone_root
*cr1
= (struct clone_root
*)e1
;
1184 struct clone_root
*cr2
= (struct clone_root
*)e2
;
1186 if (cr1
->root
->objectid
< cr2
->root
->objectid
)
1188 if (cr1
->root
->objectid
> cr2
->root
->objectid
)
1194 * Called for every backref that is found for the current extent.
1195 * Results are collected in sctx->clone_roots->ino/offset/found_refs
1197 static int __iterate_backrefs(u64 ino
, u64 offset
, u64 root
, void *ctx_
)
1199 struct backref_ctx
*bctx
= ctx_
;
1200 struct clone_root
*found
;
1204 /* First check if the root is in the list of accepted clone sources */
1205 found
= bsearch((void *)(uintptr_t)root
, bctx
->sctx
->clone_roots
,
1206 bctx
->sctx
->clone_roots_cnt
,
1207 sizeof(struct clone_root
),
1208 __clone_root_cmp_bsearch
);
1212 if (found
->root
== bctx
->sctx
->send_root
&&
1213 ino
== bctx
->cur_objectid
&&
1214 offset
== bctx
->cur_offset
) {
1215 bctx
->found_itself
= 1;
1219 * There are inodes that have extents that lie behind its i_size. Don't
1220 * accept clones from these extents.
1222 ret
= __get_inode_info(found
->root
, bctx
->path
, ino
, &i_size
, NULL
, NULL
,
1224 btrfs_release_path(bctx
->path
);
1228 if (offset
+ bctx
->data_offset
+ bctx
->extent_len
> i_size
)
1232 * Make sure we don't consider clones from send_root that are
1233 * behind the current inode/offset.
1235 if (found
->root
== bctx
->sctx
->send_root
) {
1237 * TODO for the moment we don't accept clones from the inode
1238 * that is currently send. We may change this when
1239 * BTRFS_IOC_CLONE_RANGE supports cloning from and to the same
1242 if (ino
>= bctx
->cur_objectid
)
1245 if (ino
> bctx
->cur_objectid
)
1247 if (offset
+ bctx
->extent_len
> bctx
->cur_offset
)
1253 found
->found_refs
++;
1254 if (ino
< found
->ino
) {
1256 found
->offset
= offset
;
1257 } else if (found
->ino
== ino
) {
1259 * same extent found more then once in the same file.
1261 if (found
->offset
> offset
+ bctx
->extent_len
)
1262 found
->offset
= offset
;
1269 * Given an inode, offset and extent item, it finds a good clone for a clone
1270 * instruction. Returns -ENOENT when none could be found. The function makes
1271 * sure that the returned clone is usable at the point where sending is at the
1272 * moment. This means, that no clones are accepted which lie behind the current
1275 * path must point to the extent item when called.
1277 static int find_extent_clone(struct send_ctx
*sctx
,
1278 struct btrfs_path
*path
,
1279 u64 ino
, u64 data_offset
,
1281 struct clone_root
**found
)
1288 u64 extent_item_pos
;
1290 struct btrfs_file_extent_item
*fi
;
1291 struct extent_buffer
*eb
= path
->nodes
[0];
1292 struct backref_ctx
*backref_ctx
= NULL
;
1293 struct clone_root
*cur_clone_root
;
1294 struct btrfs_key found_key
;
1295 struct btrfs_path
*tmp_path
;
1299 tmp_path
= alloc_path_for_send();
1303 /* We only use this path under the commit sem */
1304 tmp_path
->need_commit_sem
= 0;
1306 backref_ctx
= kmalloc(sizeof(*backref_ctx
), GFP_NOFS
);
1312 backref_ctx
->path
= tmp_path
;
1314 if (data_offset
>= ino_size
) {
1316 * There may be extents that lie behind the file's size.
1317 * I at least had this in combination with snapshotting while
1318 * writing large files.
1324 fi
= btrfs_item_ptr(eb
, path
->slots
[0],
1325 struct btrfs_file_extent_item
);
1326 extent_type
= btrfs_file_extent_type(eb
, fi
);
1327 if (extent_type
== BTRFS_FILE_EXTENT_INLINE
) {
1331 compressed
= btrfs_file_extent_compression(eb
, fi
);
1333 num_bytes
= btrfs_file_extent_num_bytes(eb
, fi
);
1334 disk_byte
= btrfs_file_extent_disk_bytenr(eb
, fi
);
1335 if (disk_byte
== 0) {
1339 logical
= disk_byte
+ btrfs_file_extent_offset(eb
, fi
);
1341 down_read(&sctx
->send_root
->fs_info
->commit_root_sem
);
1342 ret
= extent_from_logical(sctx
->send_root
->fs_info
, disk_byte
, tmp_path
,
1343 &found_key
, &flags
);
1344 up_read(&sctx
->send_root
->fs_info
->commit_root_sem
);
1345 btrfs_release_path(tmp_path
);
1349 if (flags
& BTRFS_EXTENT_FLAG_TREE_BLOCK
) {
1355 * Setup the clone roots.
1357 for (i
= 0; i
< sctx
->clone_roots_cnt
; i
++) {
1358 cur_clone_root
= sctx
->clone_roots
+ i
;
1359 cur_clone_root
->ino
= (u64
)-1;
1360 cur_clone_root
->offset
= 0;
1361 cur_clone_root
->found_refs
= 0;
1364 backref_ctx
->sctx
= sctx
;
1365 backref_ctx
->found
= 0;
1366 backref_ctx
->cur_objectid
= ino
;
1367 backref_ctx
->cur_offset
= data_offset
;
1368 backref_ctx
->found_itself
= 0;
1369 backref_ctx
->extent_len
= num_bytes
;
1371 * For non-compressed extents iterate_extent_inodes() gives us extent
1372 * offsets that already take into account the data offset, but not for
1373 * compressed extents, since the offset is logical and not relative to
1374 * the physical extent locations. We must take this into account to
1375 * avoid sending clone offsets that go beyond the source file's size,
1376 * which would result in the clone ioctl failing with -EINVAL on the
1379 if (compressed
== BTRFS_COMPRESS_NONE
)
1380 backref_ctx
->data_offset
= 0;
1382 backref_ctx
->data_offset
= btrfs_file_extent_offset(eb
, fi
);
1385 * The last extent of a file may be too large due to page alignment.
1386 * We need to adjust extent_len in this case so that the checks in
1387 * __iterate_backrefs work.
1389 if (data_offset
+ num_bytes
>= ino_size
)
1390 backref_ctx
->extent_len
= ino_size
- data_offset
;
1393 * Now collect all backrefs.
1395 if (compressed
== BTRFS_COMPRESS_NONE
)
1396 extent_item_pos
= logical
- found_key
.objectid
;
1398 extent_item_pos
= 0;
1399 ret
= iterate_extent_inodes(sctx
->send_root
->fs_info
,
1400 found_key
.objectid
, extent_item_pos
, 1,
1401 __iterate_backrefs
, backref_ctx
);
1406 if (!backref_ctx
->found_itself
) {
1407 /* found a bug in backref code? */
1409 btrfs_err(sctx
->send_root
->fs_info
, "did not find backref in "
1410 "send_root. inode=%llu, offset=%llu, "
1411 "disk_byte=%llu found extent=%llu",
1412 ino
, data_offset
, disk_byte
, found_key
.objectid
);
1416 verbose_printk(KERN_DEBUG
"btrfs: find_extent_clone: data_offset=%llu, "
1418 "num_bytes=%llu, logical=%llu\n",
1419 data_offset
, ino
, num_bytes
, logical
);
1421 if (!backref_ctx
->found
)
1422 verbose_printk("btrfs: no clones found\n");
1424 cur_clone_root
= NULL
;
1425 for (i
= 0; i
< sctx
->clone_roots_cnt
; i
++) {
1426 if (sctx
->clone_roots
[i
].found_refs
) {
1427 if (!cur_clone_root
)
1428 cur_clone_root
= sctx
->clone_roots
+ i
;
1429 else if (sctx
->clone_roots
[i
].root
== sctx
->send_root
)
1430 /* prefer clones from send_root over others */
1431 cur_clone_root
= sctx
->clone_roots
+ i
;
1436 if (cur_clone_root
) {
1437 if (compressed
!= BTRFS_COMPRESS_NONE
) {
1439 * Offsets given by iterate_extent_inodes() are relative
1440 * to the start of the extent, we need to add logical
1441 * offset from the file extent item.
1442 * (See why at backref.c:check_extent_in_eb())
1444 cur_clone_root
->offset
+= btrfs_file_extent_offset(eb
,
1447 *found
= cur_clone_root
;
1454 btrfs_free_path(tmp_path
);
1459 static int read_symlink(struct btrfs_root
*root
,
1461 struct fs_path
*dest
)
1464 struct btrfs_path
*path
;
1465 struct btrfs_key key
;
1466 struct btrfs_file_extent_item
*ei
;
1472 path
= alloc_path_for_send();
1477 key
.type
= BTRFS_EXTENT_DATA_KEY
;
1479 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
1484 ei
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
1485 struct btrfs_file_extent_item
);
1486 type
= btrfs_file_extent_type(path
->nodes
[0], ei
);
1487 compression
= btrfs_file_extent_compression(path
->nodes
[0], ei
);
1488 BUG_ON(type
!= BTRFS_FILE_EXTENT_INLINE
);
1489 BUG_ON(compression
);
1491 off
= btrfs_file_extent_inline_start(ei
);
1492 len
= btrfs_file_extent_inline_len(path
->nodes
[0], path
->slots
[0], ei
);
1494 ret
= fs_path_add_from_extent_buffer(dest
, path
->nodes
[0], off
, len
);
1497 btrfs_free_path(path
);
1502 * Helper function to generate a file name that is unique in the root of
1503 * send_root and parent_root. This is used to generate names for orphan inodes.
1505 static int gen_unique_name(struct send_ctx
*sctx
,
1507 struct fs_path
*dest
)
1510 struct btrfs_path
*path
;
1511 struct btrfs_dir_item
*di
;
1516 path
= alloc_path_for_send();
1521 len
= snprintf(tmp
, sizeof(tmp
), "o%llu-%llu-%llu",
1523 ASSERT(len
< sizeof(tmp
));
1525 di
= btrfs_lookup_dir_item(NULL
, sctx
->send_root
,
1526 path
, BTRFS_FIRST_FREE_OBJECTID
,
1527 tmp
, strlen(tmp
), 0);
1528 btrfs_release_path(path
);
1534 /* not unique, try again */
1539 if (!sctx
->parent_root
) {
1545 di
= btrfs_lookup_dir_item(NULL
, sctx
->parent_root
,
1546 path
, BTRFS_FIRST_FREE_OBJECTID
,
1547 tmp
, strlen(tmp
), 0);
1548 btrfs_release_path(path
);
1554 /* not unique, try again */
1562 ret
= fs_path_add(dest
, tmp
, strlen(tmp
));
1565 btrfs_free_path(path
);
1570 inode_state_no_change
,
1571 inode_state_will_create
,
1572 inode_state_did_create
,
1573 inode_state_will_delete
,
1574 inode_state_did_delete
,
1577 static int get_cur_inode_state(struct send_ctx
*sctx
, u64 ino
, u64 gen
)
1585 ret
= get_inode_info(sctx
->send_root
, ino
, NULL
, &left_gen
, NULL
, NULL
,
1587 if (ret
< 0 && ret
!= -ENOENT
)
1591 if (!sctx
->parent_root
) {
1592 right_ret
= -ENOENT
;
1594 ret
= get_inode_info(sctx
->parent_root
, ino
, NULL
, &right_gen
,
1595 NULL
, NULL
, NULL
, NULL
);
1596 if (ret
< 0 && ret
!= -ENOENT
)
1601 if (!left_ret
&& !right_ret
) {
1602 if (left_gen
== gen
&& right_gen
== gen
) {
1603 ret
= inode_state_no_change
;
1604 } else if (left_gen
== gen
) {
1605 if (ino
< sctx
->send_progress
)
1606 ret
= inode_state_did_create
;
1608 ret
= inode_state_will_create
;
1609 } else if (right_gen
== gen
) {
1610 if (ino
< sctx
->send_progress
)
1611 ret
= inode_state_did_delete
;
1613 ret
= inode_state_will_delete
;
1617 } else if (!left_ret
) {
1618 if (left_gen
== gen
) {
1619 if (ino
< sctx
->send_progress
)
1620 ret
= inode_state_did_create
;
1622 ret
= inode_state_will_create
;
1626 } else if (!right_ret
) {
1627 if (right_gen
== gen
) {
1628 if (ino
< sctx
->send_progress
)
1629 ret
= inode_state_did_delete
;
1631 ret
= inode_state_will_delete
;
1643 static int is_inode_existent(struct send_ctx
*sctx
, u64 ino
, u64 gen
)
1647 ret
= get_cur_inode_state(sctx
, ino
, gen
);
1651 if (ret
== inode_state_no_change
||
1652 ret
== inode_state_did_create
||
1653 ret
== inode_state_will_delete
)
1663 * Helper function to lookup a dir item in a dir.
1665 static int lookup_dir_item_inode(struct btrfs_root
*root
,
1666 u64 dir
, const char *name
, int name_len
,
1671 struct btrfs_dir_item
*di
;
1672 struct btrfs_key key
;
1673 struct btrfs_path
*path
;
1675 path
= alloc_path_for_send();
1679 di
= btrfs_lookup_dir_item(NULL
, root
, path
,
1680 dir
, name
, name_len
, 0);
1689 btrfs_dir_item_key_to_cpu(path
->nodes
[0], di
, &key
);
1690 if (key
.type
== BTRFS_ROOT_ITEM_KEY
) {
1694 *found_inode
= key
.objectid
;
1695 *found_type
= btrfs_dir_type(path
->nodes
[0], di
);
1698 btrfs_free_path(path
);
1703 * Looks up the first btrfs_inode_ref of a given ino. It returns the parent dir,
1704 * generation of the parent dir and the name of the dir entry.
1706 static int get_first_ref(struct btrfs_root
*root
, u64 ino
,
1707 u64
*dir
, u64
*dir_gen
, struct fs_path
*name
)
1710 struct btrfs_key key
;
1711 struct btrfs_key found_key
;
1712 struct btrfs_path
*path
;
1716 path
= alloc_path_for_send();
1721 key
.type
= BTRFS_INODE_REF_KEY
;
1724 ret
= btrfs_search_slot_for_read(root
, &key
, path
, 1, 0);
1728 btrfs_item_key_to_cpu(path
->nodes
[0], &found_key
,
1730 if (ret
|| found_key
.objectid
!= ino
||
1731 (found_key
.type
!= BTRFS_INODE_REF_KEY
&&
1732 found_key
.type
!= BTRFS_INODE_EXTREF_KEY
)) {
1737 if (found_key
.type
== BTRFS_INODE_REF_KEY
) {
1738 struct btrfs_inode_ref
*iref
;
1739 iref
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
1740 struct btrfs_inode_ref
);
1741 len
= btrfs_inode_ref_name_len(path
->nodes
[0], iref
);
1742 ret
= fs_path_add_from_extent_buffer(name
, path
->nodes
[0],
1743 (unsigned long)(iref
+ 1),
1745 parent_dir
= found_key
.offset
;
1747 struct btrfs_inode_extref
*extref
;
1748 extref
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
1749 struct btrfs_inode_extref
);
1750 len
= btrfs_inode_extref_name_len(path
->nodes
[0], extref
);
1751 ret
= fs_path_add_from_extent_buffer(name
, path
->nodes
[0],
1752 (unsigned long)&extref
->name
, len
);
1753 parent_dir
= btrfs_inode_extref_parent(path
->nodes
[0], extref
);
1757 btrfs_release_path(path
);
1760 ret
= get_inode_info(root
, parent_dir
, NULL
, dir_gen
, NULL
,
1769 btrfs_free_path(path
);
1773 static int is_first_ref(struct btrfs_root
*root
,
1775 const char *name
, int name_len
)
1778 struct fs_path
*tmp_name
;
1781 tmp_name
= fs_path_alloc();
1785 ret
= get_first_ref(root
, ino
, &tmp_dir
, NULL
, tmp_name
);
1789 if (dir
!= tmp_dir
|| name_len
!= fs_path_len(tmp_name
)) {
1794 ret
= !memcmp(tmp_name
->start
, name
, name_len
);
1797 fs_path_free(tmp_name
);
1802 * Used by process_recorded_refs to determine if a new ref would overwrite an
1803 * already existing ref. In case it detects an overwrite, it returns the
1804 * inode/gen in who_ino/who_gen.
1805 * When an overwrite is detected, process_recorded_refs does proper orphanizing
1806 * to make sure later references to the overwritten inode are possible.
1807 * Orphanizing is however only required for the first ref of an inode.
1808 * process_recorded_refs does an additional is_first_ref check to see if
1809 * orphanizing is really required.
1811 static int will_overwrite_ref(struct send_ctx
*sctx
, u64 dir
, u64 dir_gen
,
1812 const char *name
, int name_len
,
1813 u64
*who_ino
, u64
*who_gen
)
1817 u64 other_inode
= 0;
1820 if (!sctx
->parent_root
)
1823 ret
= is_inode_existent(sctx
, dir
, dir_gen
);
1828 * If we have a parent root we need to verify that the parent dir was
1829 * not delted and then re-created, if it was then we have no overwrite
1830 * and we can just unlink this entry.
1832 if (sctx
->parent_root
) {
1833 ret
= get_inode_info(sctx
->parent_root
, dir
, NULL
, &gen
, NULL
,
1835 if (ret
< 0 && ret
!= -ENOENT
)
1845 ret
= lookup_dir_item_inode(sctx
->parent_root
, dir
, name
, name_len
,
1846 &other_inode
, &other_type
);
1847 if (ret
< 0 && ret
!= -ENOENT
)
1855 * Check if the overwritten ref was already processed. If yes, the ref
1856 * was already unlinked/moved, so we can safely assume that we will not
1857 * overwrite anything at this point in time.
1859 if (other_inode
> sctx
->send_progress
) {
1860 ret
= get_inode_info(sctx
->parent_root
, other_inode
, NULL
,
1861 who_gen
, NULL
, NULL
, NULL
, NULL
);
1866 *who_ino
= other_inode
;
1876 * Checks if the ref was overwritten by an already processed inode. This is
1877 * used by __get_cur_name_and_parent to find out if the ref was orphanized and
1878 * thus the orphan name needs be used.
1879 * process_recorded_refs also uses it to avoid unlinking of refs that were
1882 static int did_overwrite_ref(struct send_ctx
*sctx
,
1883 u64 dir
, u64 dir_gen
,
1884 u64 ino
, u64 ino_gen
,
1885 const char *name
, int name_len
)
1892 if (!sctx
->parent_root
)
1895 ret
= is_inode_existent(sctx
, dir
, dir_gen
);
1899 /* check if the ref was overwritten by another ref */
1900 ret
= lookup_dir_item_inode(sctx
->send_root
, dir
, name
, name_len
,
1901 &ow_inode
, &other_type
);
1902 if (ret
< 0 && ret
!= -ENOENT
)
1905 /* was never and will never be overwritten */
1910 ret
= get_inode_info(sctx
->send_root
, ow_inode
, NULL
, &gen
, NULL
, NULL
,
1915 if (ow_inode
== ino
&& gen
== ino_gen
) {
1921 * We know that it is or will be overwritten. Check this now.
1922 * The current inode being processed might have been the one that caused
1923 * inode 'ino' to be orphanized, therefore check if ow_inode matches
1924 * the current inode being processed.
1926 if ((ow_inode
< sctx
->send_progress
) ||
1927 (ino
!= sctx
->cur_ino
&& ow_inode
== sctx
->cur_ino
&&
1928 gen
== sctx
->cur_inode_gen
))
1938 * Same as did_overwrite_ref, but also checks if it is the first ref of an inode
1939 * that got overwritten. This is used by process_recorded_refs to determine
1940 * if it has to use the path as returned by get_cur_path or the orphan name.
1942 static int did_overwrite_first_ref(struct send_ctx
*sctx
, u64 ino
, u64 gen
)
1945 struct fs_path
*name
= NULL
;
1949 if (!sctx
->parent_root
)
1952 name
= fs_path_alloc();
1956 ret
= get_first_ref(sctx
->parent_root
, ino
, &dir
, &dir_gen
, name
);
1960 ret
= did_overwrite_ref(sctx
, dir
, dir_gen
, ino
, gen
,
1961 name
->start
, fs_path_len(name
));
1969 * Insert a name cache entry. On 32bit kernels the radix tree index is 32bit,
1970 * so we need to do some special handling in case we have clashes. This function
1971 * takes care of this with the help of name_cache_entry::radix_list.
1972 * In case of error, nce is kfreed.
1974 static int name_cache_insert(struct send_ctx
*sctx
,
1975 struct name_cache_entry
*nce
)
1978 struct list_head
*nce_head
;
1980 nce_head
= radix_tree_lookup(&sctx
->name_cache
,
1981 (unsigned long)nce
->ino
);
1983 nce_head
= kmalloc(sizeof(*nce_head
), GFP_NOFS
);
1988 INIT_LIST_HEAD(nce_head
);
1990 ret
= radix_tree_insert(&sctx
->name_cache
, nce
->ino
, nce_head
);
1997 list_add_tail(&nce
->radix_list
, nce_head
);
1998 list_add_tail(&nce
->list
, &sctx
->name_cache_list
);
1999 sctx
->name_cache_size
++;
2004 static void name_cache_delete(struct send_ctx
*sctx
,
2005 struct name_cache_entry
*nce
)
2007 struct list_head
*nce_head
;
2009 nce_head
= radix_tree_lookup(&sctx
->name_cache
,
2010 (unsigned long)nce
->ino
);
2012 btrfs_err(sctx
->send_root
->fs_info
,
2013 "name_cache_delete lookup failed ino %llu cache size %d, leaking memory",
2014 nce
->ino
, sctx
->name_cache_size
);
2017 list_del(&nce
->radix_list
);
2018 list_del(&nce
->list
);
2019 sctx
->name_cache_size
--;
2022 * We may not get to the final release of nce_head if the lookup fails
2024 if (nce_head
&& list_empty(nce_head
)) {
2025 radix_tree_delete(&sctx
->name_cache
, (unsigned long)nce
->ino
);
2030 static struct name_cache_entry
*name_cache_search(struct send_ctx
*sctx
,
2033 struct list_head
*nce_head
;
2034 struct name_cache_entry
*cur
;
2036 nce_head
= radix_tree_lookup(&sctx
->name_cache
, (unsigned long)ino
);
2040 list_for_each_entry(cur
, nce_head
, radix_list
) {
2041 if (cur
->ino
== ino
&& cur
->gen
== gen
)
2048 * Removes the entry from the list and adds it back to the end. This marks the
2049 * entry as recently used so that name_cache_clean_unused does not remove it.
2051 static void name_cache_used(struct send_ctx
*sctx
, struct name_cache_entry
*nce
)
2053 list_del(&nce
->list
);
2054 list_add_tail(&nce
->list
, &sctx
->name_cache_list
);
2058 * Remove some entries from the beginning of name_cache_list.
2060 static void name_cache_clean_unused(struct send_ctx
*sctx
)
2062 struct name_cache_entry
*nce
;
2064 if (sctx
->name_cache_size
< SEND_CTX_NAME_CACHE_CLEAN_SIZE
)
2067 while (sctx
->name_cache_size
> SEND_CTX_MAX_NAME_CACHE_SIZE
) {
2068 nce
= list_entry(sctx
->name_cache_list
.next
,
2069 struct name_cache_entry
, list
);
2070 name_cache_delete(sctx
, nce
);
2075 static void name_cache_free(struct send_ctx
*sctx
)
2077 struct name_cache_entry
*nce
;
2079 while (!list_empty(&sctx
->name_cache_list
)) {
2080 nce
= list_entry(sctx
->name_cache_list
.next
,
2081 struct name_cache_entry
, list
);
2082 name_cache_delete(sctx
, nce
);
2088 * Used by get_cur_path for each ref up to the root.
2089 * Returns 0 if it succeeded.
2090 * Returns 1 if the inode is not existent or got overwritten. In that case, the
2091 * name is an orphan name. This instructs get_cur_path to stop iterating. If 1
2092 * is returned, parent_ino/parent_gen are not guaranteed to be valid.
2093 * Returns <0 in case of error.
2095 static int __get_cur_name_and_parent(struct send_ctx
*sctx
,
2099 struct fs_path
*dest
)
2103 struct name_cache_entry
*nce
= NULL
;
2106 * First check if we already did a call to this function with the same
2107 * ino/gen. If yes, check if the cache entry is still up-to-date. If yes
2108 * return the cached result.
2110 nce
= name_cache_search(sctx
, ino
, gen
);
2112 if (ino
< sctx
->send_progress
&& nce
->need_later_update
) {
2113 name_cache_delete(sctx
, nce
);
2117 name_cache_used(sctx
, nce
);
2118 *parent_ino
= nce
->parent_ino
;
2119 *parent_gen
= nce
->parent_gen
;
2120 ret
= fs_path_add(dest
, nce
->name
, nce
->name_len
);
2129 * If the inode is not existent yet, add the orphan name and return 1.
2130 * This should only happen for the parent dir that we determine in
2133 ret
= is_inode_existent(sctx
, ino
, gen
);
2138 ret
= gen_unique_name(sctx
, ino
, gen
, dest
);
2146 * Depending on whether the inode was already processed or not, use
2147 * send_root or parent_root for ref lookup.
2149 if (ino
< sctx
->send_progress
)
2150 ret
= get_first_ref(sctx
->send_root
, ino
,
2151 parent_ino
, parent_gen
, dest
);
2153 ret
= get_first_ref(sctx
->parent_root
, ino
,
2154 parent_ino
, parent_gen
, dest
);
2159 * Check if the ref was overwritten by an inode's ref that was processed
2160 * earlier. If yes, treat as orphan and return 1.
2162 ret
= did_overwrite_ref(sctx
, *parent_ino
, *parent_gen
, ino
, gen
,
2163 dest
->start
, dest
->end
- dest
->start
);
2167 fs_path_reset(dest
);
2168 ret
= gen_unique_name(sctx
, ino
, gen
, dest
);
2176 * Store the result of the lookup in the name cache.
2178 nce
= kmalloc(sizeof(*nce
) + fs_path_len(dest
) + 1, GFP_NOFS
);
2186 nce
->parent_ino
= *parent_ino
;
2187 nce
->parent_gen
= *parent_gen
;
2188 nce
->name_len
= fs_path_len(dest
);
2190 strcpy(nce
->name
, dest
->start
);
2192 if (ino
< sctx
->send_progress
)
2193 nce
->need_later_update
= 0;
2195 nce
->need_later_update
= 1;
2197 nce_ret
= name_cache_insert(sctx
, nce
);
2200 name_cache_clean_unused(sctx
);
2207 * Magic happens here. This function returns the first ref to an inode as it
2208 * would look like while receiving the stream at this point in time.
2209 * We walk the path up to the root. For every inode in between, we check if it
2210 * was already processed/sent. If yes, we continue with the parent as found
2211 * in send_root. If not, we continue with the parent as found in parent_root.
2212 * If we encounter an inode that was deleted at this point in time, we use the
2213 * inodes "orphan" name instead of the real name and stop. Same with new inodes
2214 * that were not created yet and overwritten inodes/refs.
2216 * When do we have have orphan inodes:
2217 * 1. When an inode is freshly created and thus no valid refs are available yet
2218 * 2. When a directory lost all it's refs (deleted) but still has dir items
2219 * inside which were not processed yet (pending for move/delete). If anyone
2220 * tried to get the path to the dir items, it would get a path inside that
2222 * 3. When an inode is moved around or gets new links, it may overwrite the ref
2223 * of an unprocessed inode. If in that case the first ref would be
2224 * overwritten, the overwritten inode gets "orphanized". Later when we
2225 * process this overwritten inode, it is restored at a new place by moving
2228 * sctx->send_progress tells this function at which point in time receiving
2231 static int get_cur_path(struct send_ctx
*sctx
, u64 ino
, u64 gen
,
2232 struct fs_path
*dest
)
2235 struct fs_path
*name
= NULL
;
2236 u64 parent_inode
= 0;
2240 name
= fs_path_alloc();
2247 fs_path_reset(dest
);
2249 while (!stop
&& ino
!= BTRFS_FIRST_FREE_OBJECTID
) {
2250 struct waiting_dir_move
*wdm
;
2252 fs_path_reset(name
);
2254 if (is_waiting_for_rm(sctx
, ino
)) {
2255 ret
= gen_unique_name(sctx
, ino
, gen
, name
);
2258 ret
= fs_path_add_path(dest
, name
);
2262 wdm
= get_waiting_dir_move(sctx
, ino
);
2263 if (wdm
&& wdm
->orphanized
) {
2264 ret
= gen_unique_name(sctx
, ino
, gen
, name
);
2267 ret
= get_first_ref(sctx
->parent_root
, ino
,
2268 &parent_inode
, &parent_gen
, name
);
2270 ret
= __get_cur_name_and_parent(sctx
, ino
, gen
,
2280 ret
= fs_path_add_path(dest
, name
);
2291 fs_path_unreverse(dest
);
2296 * Sends a BTRFS_SEND_C_SUBVOL command/item to userspace
2298 static int send_subvol_begin(struct send_ctx
*sctx
)
2301 struct btrfs_root
*send_root
= sctx
->send_root
;
2302 struct btrfs_root
*parent_root
= sctx
->parent_root
;
2303 struct btrfs_path
*path
;
2304 struct btrfs_key key
;
2305 struct btrfs_root_ref
*ref
;
2306 struct extent_buffer
*leaf
;
2310 path
= btrfs_alloc_path();
2314 name
= kmalloc(BTRFS_PATH_NAME_MAX
, GFP_NOFS
);
2316 btrfs_free_path(path
);
2320 key
.objectid
= send_root
->objectid
;
2321 key
.type
= BTRFS_ROOT_BACKREF_KEY
;
2324 ret
= btrfs_search_slot_for_read(send_root
->fs_info
->tree_root
,
2333 leaf
= path
->nodes
[0];
2334 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
2335 if (key
.type
!= BTRFS_ROOT_BACKREF_KEY
||
2336 key
.objectid
!= send_root
->objectid
) {
2340 ref
= btrfs_item_ptr(leaf
, path
->slots
[0], struct btrfs_root_ref
);
2341 namelen
= btrfs_root_ref_name_len(leaf
, ref
);
2342 read_extent_buffer(leaf
, name
, (unsigned long)(ref
+ 1), namelen
);
2343 btrfs_release_path(path
);
2346 ret
= begin_cmd(sctx
, BTRFS_SEND_C_SNAPSHOT
);
2350 ret
= begin_cmd(sctx
, BTRFS_SEND_C_SUBVOL
);
2355 TLV_PUT_STRING(sctx
, BTRFS_SEND_A_PATH
, name
, namelen
);
2356 TLV_PUT_UUID(sctx
, BTRFS_SEND_A_UUID
,
2357 sctx
->send_root
->root_item
.uuid
);
2358 TLV_PUT_U64(sctx
, BTRFS_SEND_A_CTRANSID
,
2359 le64_to_cpu(sctx
->send_root
->root_item
.ctransid
));
2361 if (!btrfs_is_empty_uuid(parent_root
->root_item
.received_uuid
))
2362 TLV_PUT_UUID(sctx
, BTRFS_SEND_A_CLONE_UUID
,
2363 parent_root
->root_item
.received_uuid
);
2365 TLV_PUT_UUID(sctx
, BTRFS_SEND_A_CLONE_UUID
,
2366 parent_root
->root_item
.uuid
);
2367 TLV_PUT_U64(sctx
, BTRFS_SEND_A_CLONE_CTRANSID
,
2368 le64_to_cpu(sctx
->parent_root
->root_item
.ctransid
));
2371 ret
= send_cmd(sctx
);
2375 btrfs_free_path(path
);
2380 static int send_truncate(struct send_ctx
*sctx
, u64 ino
, u64 gen
, u64 size
)
2385 verbose_printk("btrfs: send_truncate %llu size=%llu\n", ino
, size
);
2387 p
= fs_path_alloc();
2391 ret
= begin_cmd(sctx
, BTRFS_SEND_C_TRUNCATE
);
2395 ret
= get_cur_path(sctx
, ino
, gen
, p
);
2398 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, p
);
2399 TLV_PUT_U64(sctx
, BTRFS_SEND_A_SIZE
, size
);
2401 ret
= send_cmd(sctx
);
2409 static int send_chmod(struct send_ctx
*sctx
, u64 ino
, u64 gen
, u64 mode
)
2414 verbose_printk("btrfs: send_chmod %llu mode=%llu\n", ino
, mode
);
2416 p
= fs_path_alloc();
2420 ret
= begin_cmd(sctx
, BTRFS_SEND_C_CHMOD
);
2424 ret
= get_cur_path(sctx
, ino
, gen
, p
);
2427 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, p
);
2428 TLV_PUT_U64(sctx
, BTRFS_SEND_A_MODE
, mode
& 07777);
2430 ret
= send_cmd(sctx
);
2438 static int send_chown(struct send_ctx
*sctx
, u64 ino
, u64 gen
, u64 uid
, u64 gid
)
2443 verbose_printk("btrfs: send_chown %llu uid=%llu, gid=%llu\n", ino
, uid
, gid
);
2445 p
= fs_path_alloc();
2449 ret
= begin_cmd(sctx
, BTRFS_SEND_C_CHOWN
);
2453 ret
= get_cur_path(sctx
, ino
, gen
, p
);
2456 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, p
);
2457 TLV_PUT_U64(sctx
, BTRFS_SEND_A_UID
, uid
);
2458 TLV_PUT_U64(sctx
, BTRFS_SEND_A_GID
, gid
);
2460 ret
= send_cmd(sctx
);
2468 static int send_utimes(struct send_ctx
*sctx
, u64 ino
, u64 gen
)
2471 struct fs_path
*p
= NULL
;
2472 struct btrfs_inode_item
*ii
;
2473 struct btrfs_path
*path
= NULL
;
2474 struct extent_buffer
*eb
;
2475 struct btrfs_key key
;
2478 verbose_printk("btrfs: send_utimes %llu\n", ino
);
2480 p
= fs_path_alloc();
2484 path
= alloc_path_for_send();
2491 key
.type
= BTRFS_INODE_ITEM_KEY
;
2493 ret
= btrfs_search_slot(NULL
, sctx
->send_root
, &key
, path
, 0, 0);
2497 eb
= path
->nodes
[0];
2498 slot
= path
->slots
[0];
2499 ii
= btrfs_item_ptr(eb
, slot
, struct btrfs_inode_item
);
2501 ret
= begin_cmd(sctx
, BTRFS_SEND_C_UTIMES
);
2505 ret
= get_cur_path(sctx
, ino
, gen
, p
);
2508 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, p
);
2509 TLV_PUT_BTRFS_TIMESPEC(sctx
, BTRFS_SEND_A_ATIME
, eb
, &ii
->atime
);
2510 TLV_PUT_BTRFS_TIMESPEC(sctx
, BTRFS_SEND_A_MTIME
, eb
, &ii
->mtime
);
2511 TLV_PUT_BTRFS_TIMESPEC(sctx
, BTRFS_SEND_A_CTIME
, eb
, &ii
->ctime
);
2512 /* TODO Add otime support when the otime patches get into upstream */
2514 ret
= send_cmd(sctx
);
2519 btrfs_free_path(path
);
2524 * Sends a BTRFS_SEND_C_MKXXX or SYMLINK command to user space. We don't have
2525 * a valid path yet because we did not process the refs yet. So, the inode
2526 * is created as orphan.
2528 static int send_create_inode(struct send_ctx
*sctx
, u64 ino
)
2537 verbose_printk("btrfs: send_create_inode %llu\n", ino
);
2539 p
= fs_path_alloc();
2543 if (ino
!= sctx
->cur_ino
) {
2544 ret
= get_inode_info(sctx
->send_root
, ino
, NULL
, &gen
, &mode
,
2549 gen
= sctx
->cur_inode_gen
;
2550 mode
= sctx
->cur_inode_mode
;
2551 rdev
= sctx
->cur_inode_rdev
;
2554 if (S_ISREG(mode
)) {
2555 cmd
= BTRFS_SEND_C_MKFILE
;
2556 } else if (S_ISDIR(mode
)) {
2557 cmd
= BTRFS_SEND_C_MKDIR
;
2558 } else if (S_ISLNK(mode
)) {
2559 cmd
= BTRFS_SEND_C_SYMLINK
;
2560 } else if (S_ISCHR(mode
) || S_ISBLK(mode
)) {
2561 cmd
= BTRFS_SEND_C_MKNOD
;
2562 } else if (S_ISFIFO(mode
)) {
2563 cmd
= BTRFS_SEND_C_MKFIFO
;
2564 } else if (S_ISSOCK(mode
)) {
2565 cmd
= BTRFS_SEND_C_MKSOCK
;
2567 btrfs_warn(sctx
->send_root
->fs_info
, "unexpected inode type %o",
2568 (int)(mode
& S_IFMT
));
2573 ret
= begin_cmd(sctx
, cmd
);
2577 ret
= gen_unique_name(sctx
, ino
, gen
, p
);
2581 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, p
);
2582 TLV_PUT_U64(sctx
, BTRFS_SEND_A_INO
, ino
);
2584 if (S_ISLNK(mode
)) {
2586 ret
= read_symlink(sctx
->send_root
, ino
, p
);
2589 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH_LINK
, p
);
2590 } else if (S_ISCHR(mode
) || S_ISBLK(mode
) ||
2591 S_ISFIFO(mode
) || S_ISSOCK(mode
)) {
2592 TLV_PUT_U64(sctx
, BTRFS_SEND_A_RDEV
, new_encode_dev(rdev
));
2593 TLV_PUT_U64(sctx
, BTRFS_SEND_A_MODE
, mode
);
2596 ret
= send_cmd(sctx
);
2608 * We need some special handling for inodes that get processed before the parent
2609 * directory got created. See process_recorded_refs for details.
2610 * This function does the check if we already created the dir out of order.
2612 static int did_create_dir(struct send_ctx
*sctx
, u64 dir
)
2615 struct btrfs_path
*path
= NULL
;
2616 struct btrfs_key key
;
2617 struct btrfs_key found_key
;
2618 struct btrfs_key di_key
;
2619 struct extent_buffer
*eb
;
2620 struct btrfs_dir_item
*di
;
2623 path
= alloc_path_for_send();
2630 key
.type
= BTRFS_DIR_INDEX_KEY
;
2632 ret
= btrfs_search_slot(NULL
, sctx
->send_root
, &key
, path
, 0, 0);
2637 eb
= path
->nodes
[0];
2638 slot
= path
->slots
[0];
2639 if (slot
>= btrfs_header_nritems(eb
)) {
2640 ret
= btrfs_next_leaf(sctx
->send_root
, path
);
2643 } else if (ret
> 0) {
2650 btrfs_item_key_to_cpu(eb
, &found_key
, slot
);
2651 if (found_key
.objectid
!= key
.objectid
||
2652 found_key
.type
!= key
.type
) {
2657 di
= btrfs_item_ptr(eb
, slot
, struct btrfs_dir_item
);
2658 btrfs_dir_item_key_to_cpu(eb
, di
, &di_key
);
2660 if (di_key
.type
!= BTRFS_ROOT_ITEM_KEY
&&
2661 di_key
.objectid
< sctx
->send_progress
) {
2670 btrfs_free_path(path
);
2675 * Only creates the inode if it is:
2676 * 1. Not a directory
2677 * 2. Or a directory which was not created already due to out of order
2678 * directories. See did_create_dir and process_recorded_refs for details.
2680 static int send_create_inode_if_needed(struct send_ctx
*sctx
)
2684 if (S_ISDIR(sctx
->cur_inode_mode
)) {
2685 ret
= did_create_dir(sctx
, sctx
->cur_ino
);
2694 ret
= send_create_inode(sctx
, sctx
->cur_ino
);
2702 struct recorded_ref
{
2703 struct list_head list
;
2706 struct fs_path
*full_path
;
2714 * We need to process new refs before deleted refs, but compare_tree gives us
2715 * everything mixed. So we first record all refs and later process them.
2716 * This function is a helper to record one ref.
2718 static int __record_ref(struct list_head
*head
, u64 dir
,
2719 u64 dir_gen
, struct fs_path
*path
)
2721 struct recorded_ref
*ref
;
2723 ref
= kmalloc(sizeof(*ref
), GFP_NOFS
);
2728 ref
->dir_gen
= dir_gen
;
2729 ref
->full_path
= path
;
2731 ref
->name
= (char *)kbasename(ref
->full_path
->start
);
2732 ref
->name_len
= ref
->full_path
->end
- ref
->name
;
2733 ref
->dir_path
= ref
->full_path
->start
;
2734 if (ref
->name
== ref
->full_path
->start
)
2735 ref
->dir_path_len
= 0;
2737 ref
->dir_path_len
= ref
->full_path
->end
-
2738 ref
->full_path
->start
- 1 - ref
->name_len
;
2740 list_add_tail(&ref
->list
, head
);
2744 static int dup_ref(struct recorded_ref
*ref
, struct list_head
*list
)
2746 struct recorded_ref
*new;
2748 new = kmalloc(sizeof(*ref
), GFP_NOFS
);
2752 new->dir
= ref
->dir
;
2753 new->dir_gen
= ref
->dir_gen
;
2754 new->full_path
= NULL
;
2755 INIT_LIST_HEAD(&new->list
);
2756 list_add_tail(&new->list
, list
);
2760 static void __free_recorded_refs(struct list_head
*head
)
2762 struct recorded_ref
*cur
;
2764 while (!list_empty(head
)) {
2765 cur
= list_entry(head
->next
, struct recorded_ref
, list
);
2766 fs_path_free(cur
->full_path
);
2767 list_del(&cur
->list
);
2772 static void free_recorded_refs(struct send_ctx
*sctx
)
2774 __free_recorded_refs(&sctx
->new_refs
);
2775 __free_recorded_refs(&sctx
->deleted_refs
);
2779 * Renames/moves a file/dir to its orphan name. Used when the first
2780 * ref of an unprocessed inode gets overwritten and for all non empty
2783 static int orphanize_inode(struct send_ctx
*sctx
, u64 ino
, u64 gen
,
2784 struct fs_path
*path
)
2787 struct fs_path
*orphan
;
2789 orphan
= fs_path_alloc();
2793 ret
= gen_unique_name(sctx
, ino
, gen
, orphan
);
2797 ret
= send_rename(sctx
, path
, orphan
);
2800 fs_path_free(orphan
);
2804 static struct orphan_dir_info
*
2805 add_orphan_dir_info(struct send_ctx
*sctx
, u64 dir_ino
)
2807 struct rb_node
**p
= &sctx
->orphan_dirs
.rb_node
;
2808 struct rb_node
*parent
= NULL
;
2809 struct orphan_dir_info
*entry
, *odi
;
2811 odi
= kmalloc(sizeof(*odi
), GFP_NOFS
);
2813 return ERR_PTR(-ENOMEM
);
2819 entry
= rb_entry(parent
, struct orphan_dir_info
, node
);
2820 if (dir_ino
< entry
->ino
) {
2822 } else if (dir_ino
> entry
->ino
) {
2823 p
= &(*p
)->rb_right
;
2830 rb_link_node(&odi
->node
, parent
, p
);
2831 rb_insert_color(&odi
->node
, &sctx
->orphan_dirs
);
2835 static struct orphan_dir_info
*
2836 get_orphan_dir_info(struct send_ctx
*sctx
, u64 dir_ino
)
2838 struct rb_node
*n
= sctx
->orphan_dirs
.rb_node
;
2839 struct orphan_dir_info
*entry
;
2842 entry
= rb_entry(n
, struct orphan_dir_info
, node
);
2843 if (dir_ino
< entry
->ino
)
2845 else if (dir_ino
> entry
->ino
)
2853 static int is_waiting_for_rm(struct send_ctx
*sctx
, u64 dir_ino
)
2855 struct orphan_dir_info
*odi
= get_orphan_dir_info(sctx
, dir_ino
);
2860 static void free_orphan_dir_info(struct send_ctx
*sctx
,
2861 struct orphan_dir_info
*odi
)
2865 rb_erase(&odi
->node
, &sctx
->orphan_dirs
);
2870 * Returns 1 if a directory can be removed at this point in time.
2871 * We check this by iterating all dir items and checking if the inode behind
2872 * the dir item was already processed.
2874 static int can_rmdir(struct send_ctx
*sctx
, u64 dir
, u64 dir_gen
,
2878 struct btrfs_root
*root
= sctx
->parent_root
;
2879 struct btrfs_path
*path
;
2880 struct btrfs_key key
;
2881 struct btrfs_key found_key
;
2882 struct btrfs_key loc
;
2883 struct btrfs_dir_item
*di
;
2886 * Don't try to rmdir the top/root subvolume dir.
2888 if (dir
== BTRFS_FIRST_FREE_OBJECTID
)
2891 path
= alloc_path_for_send();
2896 key
.type
= BTRFS_DIR_INDEX_KEY
;
2898 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
2903 struct waiting_dir_move
*dm
;
2905 if (path
->slots
[0] >= btrfs_header_nritems(path
->nodes
[0])) {
2906 ret
= btrfs_next_leaf(root
, path
);
2913 btrfs_item_key_to_cpu(path
->nodes
[0], &found_key
,
2915 if (found_key
.objectid
!= key
.objectid
||
2916 found_key
.type
!= key
.type
)
2919 di
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
2920 struct btrfs_dir_item
);
2921 btrfs_dir_item_key_to_cpu(path
->nodes
[0], di
, &loc
);
2923 dm
= get_waiting_dir_move(sctx
, loc
.objectid
);
2925 struct orphan_dir_info
*odi
;
2927 odi
= add_orphan_dir_info(sctx
, dir
);
2933 dm
->rmdir_ino
= dir
;
2938 if (loc
.objectid
> send_progress
) {
2949 btrfs_free_path(path
);
2953 static int is_waiting_for_move(struct send_ctx
*sctx
, u64 ino
)
2955 struct waiting_dir_move
*entry
= get_waiting_dir_move(sctx
, ino
);
2957 return entry
!= NULL
;
2960 static int add_waiting_dir_move(struct send_ctx
*sctx
, u64 ino
, bool orphanized
)
2962 struct rb_node
**p
= &sctx
->waiting_dir_moves
.rb_node
;
2963 struct rb_node
*parent
= NULL
;
2964 struct waiting_dir_move
*entry
, *dm
;
2966 dm
= kmalloc(sizeof(*dm
), GFP_NOFS
);
2971 dm
->orphanized
= orphanized
;
2975 entry
= rb_entry(parent
, struct waiting_dir_move
, node
);
2976 if (ino
< entry
->ino
) {
2978 } else if (ino
> entry
->ino
) {
2979 p
= &(*p
)->rb_right
;
2986 rb_link_node(&dm
->node
, parent
, p
);
2987 rb_insert_color(&dm
->node
, &sctx
->waiting_dir_moves
);
2991 static struct waiting_dir_move
*
2992 get_waiting_dir_move(struct send_ctx
*sctx
, u64 ino
)
2994 struct rb_node
*n
= sctx
->waiting_dir_moves
.rb_node
;
2995 struct waiting_dir_move
*entry
;
2998 entry
= rb_entry(n
, struct waiting_dir_move
, node
);
2999 if (ino
< entry
->ino
)
3001 else if (ino
> entry
->ino
)
3009 static void free_waiting_dir_move(struct send_ctx
*sctx
,
3010 struct waiting_dir_move
*dm
)
3014 rb_erase(&dm
->node
, &sctx
->waiting_dir_moves
);
3018 static int add_pending_dir_move(struct send_ctx
*sctx
,
3022 struct list_head
*new_refs
,
3023 struct list_head
*deleted_refs
,
3024 const bool is_orphan
)
3026 struct rb_node
**p
= &sctx
->pending_dir_moves
.rb_node
;
3027 struct rb_node
*parent
= NULL
;
3028 struct pending_dir_move
*entry
= NULL
, *pm
;
3029 struct recorded_ref
*cur
;
3033 pm
= kmalloc(sizeof(*pm
), GFP_NOFS
);
3036 pm
->parent_ino
= parent_ino
;
3039 pm
->is_orphan
= is_orphan
;
3040 INIT_LIST_HEAD(&pm
->list
);
3041 INIT_LIST_HEAD(&pm
->update_refs
);
3042 RB_CLEAR_NODE(&pm
->node
);
3046 entry
= rb_entry(parent
, struct pending_dir_move
, node
);
3047 if (parent_ino
< entry
->parent_ino
) {
3049 } else if (parent_ino
> entry
->parent_ino
) {
3050 p
= &(*p
)->rb_right
;
3057 list_for_each_entry(cur
, deleted_refs
, list
) {
3058 ret
= dup_ref(cur
, &pm
->update_refs
);
3062 list_for_each_entry(cur
, new_refs
, list
) {
3063 ret
= dup_ref(cur
, &pm
->update_refs
);
3068 ret
= add_waiting_dir_move(sctx
, pm
->ino
, is_orphan
);
3073 list_add_tail(&pm
->list
, &entry
->list
);
3075 rb_link_node(&pm
->node
, parent
, p
);
3076 rb_insert_color(&pm
->node
, &sctx
->pending_dir_moves
);
3081 __free_recorded_refs(&pm
->update_refs
);
3087 static struct pending_dir_move
*get_pending_dir_moves(struct send_ctx
*sctx
,
3090 struct rb_node
*n
= sctx
->pending_dir_moves
.rb_node
;
3091 struct pending_dir_move
*entry
;
3094 entry
= rb_entry(n
, struct pending_dir_move
, node
);
3095 if (parent_ino
< entry
->parent_ino
)
3097 else if (parent_ino
> entry
->parent_ino
)
3105 static int apply_dir_move(struct send_ctx
*sctx
, struct pending_dir_move
*pm
)
3107 struct fs_path
*from_path
= NULL
;
3108 struct fs_path
*to_path
= NULL
;
3109 struct fs_path
*name
= NULL
;
3110 u64 orig_progress
= sctx
->send_progress
;
3111 struct recorded_ref
*cur
;
3112 u64 parent_ino
, parent_gen
;
3113 struct waiting_dir_move
*dm
= NULL
;
3117 name
= fs_path_alloc();
3118 from_path
= fs_path_alloc();
3119 if (!name
|| !from_path
) {
3124 dm
= get_waiting_dir_move(sctx
, pm
->ino
);
3126 rmdir_ino
= dm
->rmdir_ino
;
3127 free_waiting_dir_move(sctx
, dm
);
3129 if (pm
->is_orphan
) {
3130 ret
= gen_unique_name(sctx
, pm
->ino
,
3131 pm
->gen
, from_path
);
3133 ret
= get_first_ref(sctx
->parent_root
, pm
->ino
,
3134 &parent_ino
, &parent_gen
, name
);
3137 ret
= get_cur_path(sctx
, parent_ino
, parent_gen
,
3141 ret
= fs_path_add_path(from_path
, name
);
3146 sctx
->send_progress
= sctx
->cur_ino
+ 1;
3147 fs_path_reset(name
);
3150 ret
= get_cur_path(sctx
, pm
->ino
, pm
->gen
, to_path
);
3154 ret
= send_rename(sctx
, from_path
, to_path
);
3159 struct orphan_dir_info
*odi
;
3161 odi
= get_orphan_dir_info(sctx
, rmdir_ino
);
3163 /* already deleted */
3166 ret
= can_rmdir(sctx
, rmdir_ino
, odi
->gen
, sctx
->cur_ino
+ 1);
3172 name
= fs_path_alloc();
3177 ret
= get_cur_path(sctx
, rmdir_ino
, odi
->gen
, name
);
3180 ret
= send_rmdir(sctx
, name
);
3183 free_orphan_dir_info(sctx
, odi
);
3187 ret
= send_utimes(sctx
, pm
->ino
, pm
->gen
);
3192 * After rename/move, need to update the utimes of both new parent(s)
3193 * and old parent(s).
3195 list_for_each_entry(cur
, &pm
->update_refs
, list
) {
3196 if (cur
->dir
== rmdir_ino
)
3198 ret
= send_utimes(sctx
, cur
->dir
, cur
->dir_gen
);
3205 fs_path_free(from_path
);
3206 fs_path_free(to_path
);
3207 sctx
->send_progress
= orig_progress
;
3212 static void free_pending_move(struct send_ctx
*sctx
, struct pending_dir_move
*m
)
3214 if (!list_empty(&m
->list
))
3216 if (!RB_EMPTY_NODE(&m
->node
))
3217 rb_erase(&m
->node
, &sctx
->pending_dir_moves
);
3218 __free_recorded_refs(&m
->update_refs
);
3222 static void tail_append_pending_moves(struct pending_dir_move
*moves
,
3223 struct list_head
*stack
)
3225 if (list_empty(&moves
->list
)) {
3226 list_add_tail(&moves
->list
, stack
);
3229 list_splice_init(&moves
->list
, &list
);
3230 list_add_tail(&moves
->list
, stack
);
3231 list_splice_tail(&list
, stack
);
3235 static int apply_children_dir_moves(struct send_ctx
*sctx
)
3237 struct pending_dir_move
*pm
;
3238 struct list_head stack
;
3239 u64 parent_ino
= sctx
->cur_ino
;
3242 pm
= get_pending_dir_moves(sctx
, parent_ino
);
3246 INIT_LIST_HEAD(&stack
);
3247 tail_append_pending_moves(pm
, &stack
);
3249 while (!list_empty(&stack
)) {
3250 pm
= list_first_entry(&stack
, struct pending_dir_move
, list
);
3251 parent_ino
= pm
->ino
;
3252 ret
= apply_dir_move(sctx
, pm
);
3253 free_pending_move(sctx
, pm
);
3256 pm
= get_pending_dir_moves(sctx
, parent_ino
);
3258 tail_append_pending_moves(pm
, &stack
);
3263 while (!list_empty(&stack
)) {
3264 pm
= list_first_entry(&stack
, struct pending_dir_move
, list
);
3265 free_pending_move(sctx
, pm
);
3271 * We might need to delay a directory rename even when no ancestor directory
3272 * (in the send root) with a higher inode number than ours (sctx->cur_ino) was
3273 * renamed. This happens when we rename a directory to the old name (the name
3274 * in the parent root) of some other unrelated directory that got its rename
3275 * delayed due to some ancestor with higher number that got renamed.
3281 * |---- a/ (ino 257)
3282 * | |---- file (ino 260)
3284 * |---- b/ (ino 258)
3285 * |---- c/ (ino 259)
3289 * |---- a/ (ino 258)
3290 * |---- x/ (ino 259)
3291 * |---- y/ (ino 257)
3292 * |----- file (ino 260)
3294 * Here we can not rename 258 from 'b' to 'a' without the rename of inode 257
3295 * from 'a' to 'x/y' happening first, which in turn depends on the rename of
3296 * inode 259 from 'c' to 'x'. So the order of rename commands the send stream
3299 * 1 - rename 259 from 'c' to 'x'
3300 * 2 - rename 257 from 'a' to 'x/y'
3301 * 3 - rename 258 from 'b' to 'a'
3303 * Returns 1 if the rename of sctx->cur_ino needs to be delayed, 0 if it can
3304 * be done right away and < 0 on error.
3306 static int wait_for_dest_dir_move(struct send_ctx
*sctx
,
3307 struct recorded_ref
*parent_ref
,
3308 const bool is_orphan
)
3310 struct btrfs_path
*path
;
3311 struct btrfs_key key
;
3312 struct btrfs_key di_key
;
3313 struct btrfs_dir_item
*di
;
3318 if (RB_EMPTY_ROOT(&sctx
->waiting_dir_moves
))
3321 path
= alloc_path_for_send();
3325 key
.objectid
= parent_ref
->dir
;
3326 key
.type
= BTRFS_DIR_ITEM_KEY
;
3327 key
.offset
= btrfs_name_hash(parent_ref
->name
, parent_ref
->name_len
);
3329 ret
= btrfs_search_slot(NULL
, sctx
->parent_root
, &key
, path
, 0, 0);
3332 } else if (ret
> 0) {
3337 di
= btrfs_match_dir_item_name(sctx
->parent_root
, path
,
3338 parent_ref
->name
, parent_ref
->name_len
);
3344 * di_key.objectid has the number of the inode that has a dentry in the
3345 * parent directory with the same name that sctx->cur_ino is being
3346 * renamed to. We need to check if that inode is in the send root as
3347 * well and if it is currently marked as an inode with a pending rename,
3348 * if it is, we need to delay the rename of sctx->cur_ino as well, so
3349 * that it happens after that other inode is renamed.
3351 btrfs_dir_item_key_to_cpu(path
->nodes
[0], di
, &di_key
);
3352 if (di_key
.type
!= BTRFS_INODE_ITEM_KEY
) {
3357 ret
= get_inode_info(sctx
->parent_root
, di_key
.objectid
, NULL
,
3358 &left_gen
, NULL
, NULL
, NULL
, NULL
);
3361 ret
= get_inode_info(sctx
->send_root
, di_key
.objectid
, NULL
,
3362 &right_gen
, NULL
, NULL
, NULL
, NULL
);
3369 /* Different inode, no need to delay the rename of sctx->cur_ino */
3370 if (right_gen
!= left_gen
) {
3375 if (is_waiting_for_move(sctx
, di_key
.objectid
)) {
3376 ret
= add_pending_dir_move(sctx
,
3378 sctx
->cur_inode_gen
,
3381 &sctx
->deleted_refs
,
3387 btrfs_free_path(path
);
3392 * Check if ino ino1 is an ancestor of inode ino2 in the given root.
3393 * Return 1 if true, 0 if false and < 0 on error.
3395 static int is_ancestor(struct btrfs_root
*root
,
3399 struct fs_path
*fs_path
)
3403 while (ino
> BTRFS_FIRST_FREE_OBJECTID
) {
3408 fs_path_reset(fs_path
);
3409 ret
= get_first_ref(root
, ino
, &parent
, &parent_gen
, fs_path
);
3411 if (ret
== -ENOENT
&& ino
== ino2
)
3416 return parent_gen
== ino1_gen
? 1 : 0;
3422 static int wait_for_parent_move(struct send_ctx
*sctx
,
3423 struct recorded_ref
*parent_ref
,
3424 const bool is_orphan
)
3427 u64 ino
= parent_ref
->dir
;
3428 u64 parent_ino_before
, parent_ino_after
;
3429 struct fs_path
*path_before
= NULL
;
3430 struct fs_path
*path_after
= NULL
;
3433 path_after
= fs_path_alloc();
3434 path_before
= fs_path_alloc();
3435 if (!path_after
|| !path_before
) {
3441 * Our current directory inode may not yet be renamed/moved because some
3442 * ancestor (immediate or not) has to be renamed/moved first. So find if
3443 * such ancestor exists and make sure our own rename/move happens after
3444 * that ancestor is processed to avoid path build infinite loops (done
3445 * at get_cur_path()).
3447 while (ino
> BTRFS_FIRST_FREE_OBJECTID
) {
3448 if (is_waiting_for_move(sctx
, ino
)) {
3450 * If the current inode is an ancestor of ino in the
3451 * parent root, we need to delay the rename of the
3452 * current inode, otherwise don't delayed the rename
3453 * because we can end up with a circular dependency
3454 * of renames, resulting in some directories never
3455 * getting the respective rename operations issued in
3456 * the send stream or getting into infinite path build
3459 ret
= is_ancestor(sctx
->parent_root
,
3460 sctx
->cur_ino
, sctx
->cur_inode_gen
,
3465 fs_path_reset(path_before
);
3466 fs_path_reset(path_after
);
3468 ret
= get_first_ref(sctx
->send_root
, ino
, &parent_ino_after
,
3472 ret
= get_first_ref(sctx
->parent_root
, ino
, &parent_ino_before
,
3474 if (ret
< 0 && ret
!= -ENOENT
) {
3476 } else if (ret
== -ENOENT
) {
3481 len1
= fs_path_len(path_before
);
3482 len2
= fs_path_len(path_after
);
3483 if (ino
> sctx
->cur_ino
&&
3484 (parent_ino_before
!= parent_ino_after
|| len1
!= len2
||
3485 memcmp(path_before
->start
, path_after
->start
, len1
))) {
3489 ino
= parent_ino_after
;
3493 fs_path_free(path_before
);
3494 fs_path_free(path_after
);
3497 ret
= add_pending_dir_move(sctx
,
3499 sctx
->cur_inode_gen
,
3502 &sctx
->deleted_refs
,
3512 * This does all the move/link/unlink/rmdir magic.
3514 static int process_recorded_refs(struct send_ctx
*sctx
, int *pending_move
)
3517 struct recorded_ref
*cur
;
3518 struct recorded_ref
*cur2
;
3519 struct list_head check_dirs
;
3520 struct fs_path
*valid_path
= NULL
;
3523 int did_overwrite
= 0;
3525 u64 last_dir_ino_rm
= 0;
3526 bool can_rename
= true;
3528 verbose_printk("btrfs: process_recorded_refs %llu\n", sctx
->cur_ino
);
3531 * This should never happen as the root dir always has the same ref
3532 * which is always '..'
3534 BUG_ON(sctx
->cur_ino
<= BTRFS_FIRST_FREE_OBJECTID
);
3535 INIT_LIST_HEAD(&check_dirs
);
3537 valid_path
= fs_path_alloc();
3544 * First, check if the first ref of the current inode was overwritten
3545 * before. If yes, we know that the current inode was already orphanized
3546 * and thus use the orphan name. If not, we can use get_cur_path to
3547 * get the path of the first ref as it would like while receiving at
3548 * this point in time.
3549 * New inodes are always orphan at the beginning, so force to use the
3550 * orphan name in this case.
3551 * The first ref is stored in valid_path and will be updated if it
3552 * gets moved around.
3554 if (!sctx
->cur_inode_new
) {
3555 ret
= did_overwrite_first_ref(sctx
, sctx
->cur_ino
,
3556 sctx
->cur_inode_gen
);
3562 if (sctx
->cur_inode_new
|| did_overwrite
) {
3563 ret
= gen_unique_name(sctx
, sctx
->cur_ino
,
3564 sctx
->cur_inode_gen
, valid_path
);
3569 ret
= get_cur_path(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
,
3575 list_for_each_entry(cur
, &sctx
->new_refs
, list
) {
3577 * We may have refs where the parent directory does not exist
3578 * yet. This happens if the parent directories inum is higher
3579 * the the current inum. To handle this case, we create the
3580 * parent directory out of order. But we need to check if this
3581 * did already happen before due to other refs in the same dir.
3583 ret
= get_cur_inode_state(sctx
, cur
->dir
, cur
->dir_gen
);
3586 if (ret
== inode_state_will_create
) {
3589 * First check if any of the current inodes refs did
3590 * already create the dir.
3592 list_for_each_entry(cur2
, &sctx
->new_refs
, list
) {
3595 if (cur2
->dir
== cur
->dir
) {
3602 * If that did not happen, check if a previous inode
3603 * did already create the dir.
3606 ret
= did_create_dir(sctx
, cur
->dir
);
3610 ret
= send_create_inode(sctx
, cur
->dir
);
3617 * Check if this new ref would overwrite the first ref of
3618 * another unprocessed inode. If yes, orphanize the
3619 * overwritten inode. If we find an overwritten ref that is
3620 * not the first ref, simply unlink it.
3622 ret
= will_overwrite_ref(sctx
, cur
->dir
, cur
->dir_gen
,
3623 cur
->name
, cur
->name_len
,
3624 &ow_inode
, &ow_gen
);
3628 ret
= is_first_ref(sctx
->parent_root
,
3629 ow_inode
, cur
->dir
, cur
->name
,
3634 struct name_cache_entry
*nce
;
3636 ret
= orphanize_inode(sctx
, ow_inode
, ow_gen
,
3641 * Make sure we clear our orphanized inode's
3642 * name from the name cache. This is because the
3643 * inode ow_inode might be an ancestor of some
3644 * other inode that will be orphanized as well
3645 * later and has an inode number greater than
3646 * sctx->send_progress. We need to prevent
3647 * future name lookups from using the old name
3648 * and get instead the orphan name.
3650 nce
= name_cache_search(sctx
, ow_inode
, ow_gen
);
3652 name_cache_delete(sctx
, nce
);
3656 ret
= send_unlink(sctx
, cur
->full_path
);
3662 if (S_ISDIR(sctx
->cur_inode_mode
) && sctx
->parent_root
) {
3663 ret
= wait_for_dest_dir_move(sctx
, cur
, is_orphan
);
3672 if (S_ISDIR(sctx
->cur_inode_mode
) && sctx
->parent_root
&&
3674 ret
= wait_for_parent_move(sctx
, cur
, is_orphan
);
3684 * link/move the ref to the new place. If we have an orphan
3685 * inode, move it and update valid_path. If not, link or move
3686 * it depending on the inode mode.
3688 if (is_orphan
&& can_rename
) {
3689 ret
= send_rename(sctx
, valid_path
, cur
->full_path
);
3693 ret
= fs_path_copy(valid_path
, cur
->full_path
);
3696 } else if (can_rename
) {
3697 if (S_ISDIR(sctx
->cur_inode_mode
)) {
3699 * Dirs can't be linked, so move it. For moved
3700 * dirs, we always have one new and one deleted
3701 * ref. The deleted ref is ignored later.
3703 ret
= send_rename(sctx
, valid_path
,
3706 ret
= fs_path_copy(valid_path
,
3711 ret
= send_link(sctx
, cur
->full_path
,
3717 ret
= dup_ref(cur
, &check_dirs
);
3722 if (S_ISDIR(sctx
->cur_inode_mode
) && sctx
->cur_inode_deleted
) {
3724 * Check if we can already rmdir the directory. If not,
3725 * orphanize it. For every dir item inside that gets deleted
3726 * later, we do this check again and rmdir it then if possible.
3727 * See the use of check_dirs for more details.
3729 ret
= can_rmdir(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
,
3734 ret
= send_rmdir(sctx
, valid_path
);
3737 } else if (!is_orphan
) {
3738 ret
= orphanize_inode(sctx
, sctx
->cur_ino
,
3739 sctx
->cur_inode_gen
, valid_path
);
3745 list_for_each_entry(cur
, &sctx
->deleted_refs
, list
) {
3746 ret
= dup_ref(cur
, &check_dirs
);
3750 } else if (S_ISDIR(sctx
->cur_inode_mode
) &&
3751 !list_empty(&sctx
->deleted_refs
)) {
3753 * We have a moved dir. Add the old parent to check_dirs
3755 cur
= list_entry(sctx
->deleted_refs
.next
, struct recorded_ref
,
3757 ret
= dup_ref(cur
, &check_dirs
);
3760 } else if (!S_ISDIR(sctx
->cur_inode_mode
)) {
3762 * We have a non dir inode. Go through all deleted refs and
3763 * unlink them if they were not already overwritten by other
3766 list_for_each_entry(cur
, &sctx
->deleted_refs
, list
) {
3767 ret
= did_overwrite_ref(sctx
, cur
->dir
, cur
->dir_gen
,
3768 sctx
->cur_ino
, sctx
->cur_inode_gen
,
3769 cur
->name
, cur
->name_len
);
3773 ret
= send_unlink(sctx
, cur
->full_path
);
3777 ret
= dup_ref(cur
, &check_dirs
);
3782 * If the inode is still orphan, unlink the orphan. This may
3783 * happen when a previous inode did overwrite the first ref
3784 * of this inode and no new refs were added for the current
3785 * inode. Unlinking does not mean that the inode is deleted in
3786 * all cases. There may still be links to this inode in other
3790 ret
= send_unlink(sctx
, valid_path
);
3797 * We did collect all parent dirs where cur_inode was once located. We
3798 * now go through all these dirs and check if they are pending for
3799 * deletion and if it's finally possible to perform the rmdir now.
3800 * We also update the inode stats of the parent dirs here.
3802 list_for_each_entry(cur
, &check_dirs
, list
) {
3804 * In case we had refs into dirs that were not processed yet,
3805 * we don't need to do the utime and rmdir logic for these dirs.
3806 * The dir will be processed later.
3808 if (cur
->dir
> sctx
->cur_ino
)
3811 ret
= get_cur_inode_state(sctx
, cur
->dir
, cur
->dir_gen
);
3815 if (ret
== inode_state_did_create
||
3816 ret
== inode_state_no_change
) {
3817 /* TODO delayed utimes */
3818 ret
= send_utimes(sctx
, cur
->dir
, cur
->dir_gen
);
3821 } else if (ret
== inode_state_did_delete
&&
3822 cur
->dir
!= last_dir_ino_rm
) {
3823 ret
= can_rmdir(sctx
, cur
->dir
, cur
->dir_gen
,
3828 ret
= get_cur_path(sctx
, cur
->dir
,
3829 cur
->dir_gen
, valid_path
);
3832 ret
= send_rmdir(sctx
, valid_path
);
3835 last_dir_ino_rm
= cur
->dir
;
3843 __free_recorded_refs(&check_dirs
);
3844 free_recorded_refs(sctx
);
3845 fs_path_free(valid_path
);
3849 static int record_ref(struct btrfs_root
*root
, int num
, u64 dir
, int index
,
3850 struct fs_path
*name
, void *ctx
, struct list_head
*refs
)
3853 struct send_ctx
*sctx
= ctx
;
3857 p
= fs_path_alloc();
3861 ret
= get_inode_info(root
, dir
, NULL
, &gen
, NULL
, NULL
,
3866 ret
= get_cur_path(sctx
, dir
, gen
, p
);
3869 ret
= fs_path_add_path(p
, name
);
3873 ret
= __record_ref(refs
, dir
, gen
, p
);
3881 static int __record_new_ref(int num
, u64 dir
, int index
,
3882 struct fs_path
*name
,
3885 struct send_ctx
*sctx
= ctx
;
3886 return record_ref(sctx
->send_root
, num
, dir
, index
, name
,
3887 ctx
, &sctx
->new_refs
);
3891 static int __record_deleted_ref(int num
, u64 dir
, int index
,
3892 struct fs_path
*name
,
3895 struct send_ctx
*sctx
= ctx
;
3896 return record_ref(sctx
->parent_root
, num
, dir
, index
, name
,
3897 ctx
, &sctx
->deleted_refs
);
3900 static int record_new_ref(struct send_ctx
*sctx
)
3904 ret
= iterate_inode_ref(sctx
->send_root
, sctx
->left_path
,
3905 sctx
->cmp_key
, 0, __record_new_ref
, sctx
);
3914 static int record_deleted_ref(struct send_ctx
*sctx
)
3918 ret
= iterate_inode_ref(sctx
->parent_root
, sctx
->right_path
,
3919 sctx
->cmp_key
, 0, __record_deleted_ref
, sctx
);
3928 struct find_ref_ctx
{
3931 struct btrfs_root
*root
;
3932 struct fs_path
*name
;
3936 static int __find_iref(int num
, u64 dir
, int index
,
3937 struct fs_path
*name
,
3940 struct find_ref_ctx
*ctx
= ctx_
;
3944 if (dir
== ctx
->dir
&& fs_path_len(name
) == fs_path_len(ctx
->name
) &&
3945 strncmp(name
->start
, ctx
->name
->start
, fs_path_len(name
)) == 0) {
3947 * To avoid doing extra lookups we'll only do this if everything
3950 ret
= get_inode_info(ctx
->root
, dir
, NULL
, &dir_gen
, NULL
,
3954 if (dir_gen
!= ctx
->dir_gen
)
3956 ctx
->found_idx
= num
;
3962 static int find_iref(struct btrfs_root
*root
,
3963 struct btrfs_path
*path
,
3964 struct btrfs_key
*key
,
3965 u64 dir
, u64 dir_gen
, struct fs_path
*name
)
3968 struct find_ref_ctx ctx
;
3972 ctx
.dir_gen
= dir_gen
;
3976 ret
= iterate_inode_ref(root
, path
, key
, 0, __find_iref
, &ctx
);
3980 if (ctx
.found_idx
== -1)
3983 return ctx
.found_idx
;
3986 static int __record_changed_new_ref(int num
, u64 dir
, int index
,
3987 struct fs_path
*name
,
3992 struct send_ctx
*sctx
= ctx
;
3994 ret
= get_inode_info(sctx
->send_root
, dir
, NULL
, &dir_gen
, NULL
,
3999 ret
= find_iref(sctx
->parent_root
, sctx
->right_path
,
4000 sctx
->cmp_key
, dir
, dir_gen
, name
);
4002 ret
= __record_new_ref(num
, dir
, index
, name
, sctx
);
4009 static int __record_changed_deleted_ref(int num
, u64 dir
, int index
,
4010 struct fs_path
*name
,
4015 struct send_ctx
*sctx
= ctx
;
4017 ret
= get_inode_info(sctx
->parent_root
, dir
, NULL
, &dir_gen
, NULL
,
4022 ret
= find_iref(sctx
->send_root
, sctx
->left_path
, sctx
->cmp_key
,
4023 dir
, dir_gen
, name
);
4025 ret
= __record_deleted_ref(num
, dir
, index
, name
, sctx
);
4032 static int record_changed_ref(struct send_ctx
*sctx
)
4036 ret
= iterate_inode_ref(sctx
->send_root
, sctx
->left_path
,
4037 sctx
->cmp_key
, 0, __record_changed_new_ref
, sctx
);
4040 ret
= iterate_inode_ref(sctx
->parent_root
, sctx
->right_path
,
4041 sctx
->cmp_key
, 0, __record_changed_deleted_ref
, sctx
);
4051 * Record and process all refs at once. Needed when an inode changes the
4052 * generation number, which means that it was deleted and recreated.
4054 static int process_all_refs(struct send_ctx
*sctx
,
4055 enum btrfs_compare_tree_result cmd
)
4058 struct btrfs_root
*root
;
4059 struct btrfs_path
*path
;
4060 struct btrfs_key key
;
4061 struct btrfs_key found_key
;
4062 struct extent_buffer
*eb
;
4064 iterate_inode_ref_t cb
;
4065 int pending_move
= 0;
4067 path
= alloc_path_for_send();
4071 if (cmd
== BTRFS_COMPARE_TREE_NEW
) {
4072 root
= sctx
->send_root
;
4073 cb
= __record_new_ref
;
4074 } else if (cmd
== BTRFS_COMPARE_TREE_DELETED
) {
4075 root
= sctx
->parent_root
;
4076 cb
= __record_deleted_ref
;
4078 btrfs_err(sctx
->send_root
->fs_info
,
4079 "Wrong command %d in process_all_refs", cmd
);
4084 key
.objectid
= sctx
->cmp_key
->objectid
;
4085 key
.type
= BTRFS_INODE_REF_KEY
;
4087 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
4092 eb
= path
->nodes
[0];
4093 slot
= path
->slots
[0];
4094 if (slot
>= btrfs_header_nritems(eb
)) {
4095 ret
= btrfs_next_leaf(root
, path
);
4103 btrfs_item_key_to_cpu(eb
, &found_key
, slot
);
4105 if (found_key
.objectid
!= key
.objectid
||
4106 (found_key
.type
!= BTRFS_INODE_REF_KEY
&&
4107 found_key
.type
!= BTRFS_INODE_EXTREF_KEY
))
4110 ret
= iterate_inode_ref(root
, path
, &found_key
, 0, cb
, sctx
);
4116 btrfs_release_path(path
);
4118 ret
= process_recorded_refs(sctx
, &pending_move
);
4119 /* Only applicable to an incremental send. */
4120 ASSERT(pending_move
== 0);
4123 btrfs_free_path(path
);
4127 static int send_set_xattr(struct send_ctx
*sctx
,
4128 struct fs_path
*path
,
4129 const char *name
, int name_len
,
4130 const char *data
, int data_len
)
4134 ret
= begin_cmd(sctx
, BTRFS_SEND_C_SET_XATTR
);
4138 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, path
);
4139 TLV_PUT_STRING(sctx
, BTRFS_SEND_A_XATTR_NAME
, name
, name_len
);
4140 TLV_PUT(sctx
, BTRFS_SEND_A_XATTR_DATA
, data
, data_len
);
4142 ret
= send_cmd(sctx
);
4149 static int send_remove_xattr(struct send_ctx
*sctx
,
4150 struct fs_path
*path
,
4151 const char *name
, int name_len
)
4155 ret
= begin_cmd(sctx
, BTRFS_SEND_C_REMOVE_XATTR
);
4159 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, path
);
4160 TLV_PUT_STRING(sctx
, BTRFS_SEND_A_XATTR_NAME
, name
, name_len
);
4162 ret
= send_cmd(sctx
);
4169 static int __process_new_xattr(int num
, struct btrfs_key
*di_key
,
4170 const char *name
, int name_len
,
4171 const char *data
, int data_len
,
4175 struct send_ctx
*sctx
= ctx
;
4177 posix_acl_xattr_header dummy_acl
;
4179 p
= fs_path_alloc();
4184 * This hack is needed because empty acl's are stored as zero byte
4185 * data in xattrs. Problem with that is, that receiving these zero byte
4186 * acl's will fail later. To fix this, we send a dummy acl list that
4187 * only contains the version number and no entries.
4189 if (!strncmp(name
, XATTR_NAME_POSIX_ACL_ACCESS
, name_len
) ||
4190 !strncmp(name
, XATTR_NAME_POSIX_ACL_DEFAULT
, name_len
)) {
4191 if (data_len
== 0) {
4192 dummy_acl
.a_version
=
4193 cpu_to_le32(POSIX_ACL_XATTR_VERSION
);
4194 data
= (char *)&dummy_acl
;
4195 data_len
= sizeof(dummy_acl
);
4199 ret
= get_cur_path(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
, p
);
4203 ret
= send_set_xattr(sctx
, p
, name
, name_len
, data
, data_len
);
4210 static int __process_deleted_xattr(int num
, struct btrfs_key
*di_key
,
4211 const char *name
, int name_len
,
4212 const char *data
, int data_len
,
4216 struct send_ctx
*sctx
= ctx
;
4219 p
= fs_path_alloc();
4223 ret
= get_cur_path(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
, p
);
4227 ret
= send_remove_xattr(sctx
, p
, name
, name_len
);
4234 static int process_new_xattr(struct send_ctx
*sctx
)
4238 ret
= iterate_dir_item(sctx
->send_root
, sctx
->left_path
,
4239 sctx
->cmp_key
, __process_new_xattr
, sctx
);
4244 static int process_deleted_xattr(struct send_ctx
*sctx
)
4248 ret
= iterate_dir_item(sctx
->parent_root
, sctx
->right_path
,
4249 sctx
->cmp_key
, __process_deleted_xattr
, sctx
);
4254 struct find_xattr_ctx
{
4262 static int __find_xattr(int num
, struct btrfs_key
*di_key
,
4263 const char *name
, int name_len
,
4264 const char *data
, int data_len
,
4265 u8 type
, void *vctx
)
4267 struct find_xattr_ctx
*ctx
= vctx
;
4269 if (name_len
== ctx
->name_len
&&
4270 strncmp(name
, ctx
->name
, name_len
) == 0) {
4271 ctx
->found_idx
= num
;
4272 ctx
->found_data_len
= data_len
;
4273 ctx
->found_data
= kmemdup(data
, data_len
, GFP_NOFS
);
4274 if (!ctx
->found_data
)
4281 static int find_xattr(struct btrfs_root
*root
,
4282 struct btrfs_path
*path
,
4283 struct btrfs_key
*key
,
4284 const char *name
, int name_len
,
4285 char **data
, int *data_len
)
4288 struct find_xattr_ctx ctx
;
4291 ctx
.name_len
= name_len
;
4293 ctx
.found_data
= NULL
;
4294 ctx
.found_data_len
= 0;
4296 ret
= iterate_dir_item(root
, path
, key
, __find_xattr
, &ctx
);
4300 if (ctx
.found_idx
== -1)
4303 *data
= ctx
.found_data
;
4304 *data_len
= ctx
.found_data_len
;
4306 kfree(ctx
.found_data
);
4308 return ctx
.found_idx
;
4312 static int __process_changed_new_xattr(int num
, struct btrfs_key
*di_key
,
4313 const char *name
, int name_len
,
4314 const char *data
, int data_len
,
4318 struct send_ctx
*sctx
= ctx
;
4319 char *found_data
= NULL
;
4320 int found_data_len
= 0;
4322 ret
= find_xattr(sctx
->parent_root
, sctx
->right_path
,
4323 sctx
->cmp_key
, name
, name_len
, &found_data
,
4325 if (ret
== -ENOENT
) {
4326 ret
= __process_new_xattr(num
, di_key
, name
, name_len
, data
,
4327 data_len
, type
, ctx
);
4328 } else if (ret
>= 0) {
4329 if (data_len
!= found_data_len
||
4330 memcmp(data
, found_data
, data_len
)) {
4331 ret
= __process_new_xattr(num
, di_key
, name
, name_len
,
4332 data
, data_len
, type
, ctx
);
4342 static int __process_changed_deleted_xattr(int num
, struct btrfs_key
*di_key
,
4343 const char *name
, int name_len
,
4344 const char *data
, int data_len
,
4348 struct send_ctx
*sctx
= ctx
;
4350 ret
= find_xattr(sctx
->send_root
, sctx
->left_path
, sctx
->cmp_key
,
4351 name
, name_len
, NULL
, NULL
);
4353 ret
= __process_deleted_xattr(num
, di_key
, name
, name_len
, data
,
4354 data_len
, type
, ctx
);
4361 static int process_changed_xattr(struct send_ctx
*sctx
)
4365 ret
= iterate_dir_item(sctx
->send_root
, sctx
->left_path
,
4366 sctx
->cmp_key
, __process_changed_new_xattr
, sctx
);
4369 ret
= iterate_dir_item(sctx
->parent_root
, sctx
->right_path
,
4370 sctx
->cmp_key
, __process_changed_deleted_xattr
, sctx
);
4376 static int process_all_new_xattrs(struct send_ctx
*sctx
)
4379 struct btrfs_root
*root
;
4380 struct btrfs_path
*path
;
4381 struct btrfs_key key
;
4382 struct btrfs_key found_key
;
4383 struct extent_buffer
*eb
;
4386 path
= alloc_path_for_send();
4390 root
= sctx
->send_root
;
4392 key
.objectid
= sctx
->cmp_key
->objectid
;
4393 key
.type
= BTRFS_XATTR_ITEM_KEY
;
4395 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
4400 eb
= path
->nodes
[0];
4401 slot
= path
->slots
[0];
4402 if (slot
>= btrfs_header_nritems(eb
)) {
4403 ret
= btrfs_next_leaf(root
, path
);
4406 } else if (ret
> 0) {
4413 btrfs_item_key_to_cpu(eb
, &found_key
, slot
);
4414 if (found_key
.objectid
!= key
.objectid
||
4415 found_key
.type
!= key
.type
) {
4420 ret
= iterate_dir_item(root
, path
, &found_key
,
4421 __process_new_xattr
, sctx
);
4429 btrfs_free_path(path
);
4433 static ssize_t
fill_read_buf(struct send_ctx
*sctx
, u64 offset
, u32 len
)
4435 struct btrfs_root
*root
= sctx
->send_root
;
4436 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
4437 struct inode
*inode
;
4440 struct btrfs_key key
;
4441 pgoff_t index
= offset
>> PAGE_CACHE_SHIFT
;
4443 unsigned pg_offset
= offset
& ~PAGE_CACHE_MASK
;
4446 key
.objectid
= sctx
->cur_ino
;
4447 key
.type
= BTRFS_INODE_ITEM_KEY
;
4450 inode
= btrfs_iget(fs_info
->sb
, &key
, root
, NULL
);
4452 return PTR_ERR(inode
);
4454 if (offset
+ len
> i_size_read(inode
)) {
4455 if (offset
> i_size_read(inode
))
4458 len
= offset
- i_size_read(inode
);
4463 last_index
= (offset
+ len
- 1) >> PAGE_CACHE_SHIFT
;
4465 /* initial readahead */
4466 memset(&sctx
->ra
, 0, sizeof(struct file_ra_state
));
4467 file_ra_state_init(&sctx
->ra
, inode
->i_mapping
);
4468 btrfs_force_ra(inode
->i_mapping
, &sctx
->ra
, NULL
, index
,
4469 last_index
- index
+ 1);
4471 while (index
<= last_index
) {
4472 unsigned cur_len
= min_t(unsigned, len
,
4473 PAGE_CACHE_SIZE
- pg_offset
);
4474 page
= find_or_create_page(inode
->i_mapping
, index
, GFP_NOFS
);
4480 if (!PageUptodate(page
)) {
4481 btrfs_readpage(NULL
, page
);
4483 if (!PageUptodate(page
)) {
4485 page_cache_release(page
);
4492 memcpy(sctx
->read_buf
+ ret
, addr
+ pg_offset
, cur_len
);
4495 page_cache_release(page
);
4507 * Read some bytes from the current inode/file and send a write command to
4510 static int send_write(struct send_ctx
*sctx
, u64 offset
, u32 len
)
4514 ssize_t num_read
= 0;
4516 p
= fs_path_alloc();
4520 verbose_printk("btrfs: send_write offset=%llu, len=%d\n", offset
, len
);
4522 num_read
= fill_read_buf(sctx
, offset
, len
);
4523 if (num_read
<= 0) {
4529 ret
= begin_cmd(sctx
, BTRFS_SEND_C_WRITE
);
4533 ret
= get_cur_path(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
, p
);
4537 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, p
);
4538 TLV_PUT_U64(sctx
, BTRFS_SEND_A_FILE_OFFSET
, offset
);
4539 TLV_PUT(sctx
, BTRFS_SEND_A_DATA
, sctx
->read_buf
, num_read
);
4541 ret
= send_cmd(sctx
);
4552 * Send a clone command to user space.
4554 static int send_clone(struct send_ctx
*sctx
,
4555 u64 offset
, u32 len
,
4556 struct clone_root
*clone_root
)
4562 verbose_printk("btrfs: send_clone offset=%llu, len=%d, clone_root=%llu, "
4563 "clone_inode=%llu, clone_offset=%llu\n", offset
, len
,
4564 clone_root
->root
->objectid
, clone_root
->ino
,
4565 clone_root
->offset
);
4567 p
= fs_path_alloc();
4571 ret
= begin_cmd(sctx
, BTRFS_SEND_C_CLONE
);
4575 ret
= get_cur_path(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
, p
);
4579 TLV_PUT_U64(sctx
, BTRFS_SEND_A_FILE_OFFSET
, offset
);
4580 TLV_PUT_U64(sctx
, BTRFS_SEND_A_CLONE_LEN
, len
);
4581 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, p
);
4583 if (clone_root
->root
== sctx
->send_root
) {
4584 ret
= get_inode_info(sctx
->send_root
, clone_root
->ino
, NULL
,
4585 &gen
, NULL
, NULL
, NULL
, NULL
);
4588 ret
= get_cur_path(sctx
, clone_root
->ino
, gen
, p
);
4590 ret
= get_inode_path(clone_root
->root
, clone_root
->ino
, p
);
4596 * If the parent we're using has a received_uuid set then use that as
4597 * our clone source as that is what we will look for when doing a
4600 * This covers the case that we create a snapshot off of a received
4601 * subvolume and then use that as the parent and try to receive on a
4604 if (!btrfs_is_empty_uuid(clone_root
->root
->root_item
.received_uuid
))
4605 TLV_PUT_UUID(sctx
, BTRFS_SEND_A_CLONE_UUID
,
4606 clone_root
->root
->root_item
.received_uuid
);
4608 TLV_PUT_UUID(sctx
, BTRFS_SEND_A_CLONE_UUID
,
4609 clone_root
->root
->root_item
.uuid
);
4610 TLV_PUT_U64(sctx
, BTRFS_SEND_A_CLONE_CTRANSID
,
4611 le64_to_cpu(clone_root
->root
->root_item
.ctransid
));
4612 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_CLONE_PATH
, p
);
4613 TLV_PUT_U64(sctx
, BTRFS_SEND_A_CLONE_OFFSET
,
4614 clone_root
->offset
);
4616 ret
= send_cmd(sctx
);
4625 * Send an update extent command to user space.
4627 static int send_update_extent(struct send_ctx
*sctx
,
4628 u64 offset
, u32 len
)
4633 p
= fs_path_alloc();
4637 ret
= begin_cmd(sctx
, BTRFS_SEND_C_UPDATE_EXTENT
);
4641 ret
= get_cur_path(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
, p
);
4645 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, p
);
4646 TLV_PUT_U64(sctx
, BTRFS_SEND_A_FILE_OFFSET
, offset
);
4647 TLV_PUT_U64(sctx
, BTRFS_SEND_A_SIZE
, len
);
4649 ret
= send_cmd(sctx
);
4657 static int send_hole(struct send_ctx
*sctx
, u64 end
)
4659 struct fs_path
*p
= NULL
;
4660 u64 offset
= sctx
->cur_inode_last_extent
;
4664 p
= fs_path_alloc();
4667 ret
= get_cur_path(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
, p
);
4669 goto tlv_put_failure
;
4670 memset(sctx
->read_buf
, 0, BTRFS_SEND_READ_SIZE
);
4671 while (offset
< end
) {
4672 len
= min_t(u64
, end
- offset
, BTRFS_SEND_READ_SIZE
);
4674 ret
= begin_cmd(sctx
, BTRFS_SEND_C_WRITE
);
4677 TLV_PUT_PATH(sctx
, BTRFS_SEND_A_PATH
, p
);
4678 TLV_PUT_U64(sctx
, BTRFS_SEND_A_FILE_OFFSET
, offset
);
4679 TLV_PUT(sctx
, BTRFS_SEND_A_DATA
, sctx
->read_buf
, len
);
4680 ret
= send_cmd(sctx
);
4690 static int send_write_or_clone(struct send_ctx
*sctx
,
4691 struct btrfs_path
*path
,
4692 struct btrfs_key
*key
,
4693 struct clone_root
*clone_root
)
4696 struct btrfs_file_extent_item
*ei
;
4697 u64 offset
= key
->offset
;
4702 u64 bs
= sctx
->send_root
->fs_info
->sb
->s_blocksize
;
4704 ei
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
4705 struct btrfs_file_extent_item
);
4706 type
= btrfs_file_extent_type(path
->nodes
[0], ei
);
4707 if (type
== BTRFS_FILE_EXTENT_INLINE
) {
4708 len
= btrfs_file_extent_inline_len(path
->nodes
[0],
4709 path
->slots
[0], ei
);
4711 * it is possible the inline item won't cover the whole page,
4712 * but there may be items after this page. Make
4713 * sure to send the whole thing
4715 len
= PAGE_CACHE_ALIGN(len
);
4717 len
= btrfs_file_extent_num_bytes(path
->nodes
[0], ei
);
4720 if (offset
+ len
> sctx
->cur_inode_size
)
4721 len
= sctx
->cur_inode_size
- offset
;
4727 if (clone_root
&& IS_ALIGNED(offset
+ len
, bs
)) {
4728 ret
= send_clone(sctx
, offset
, len
, clone_root
);
4729 } else if (sctx
->flags
& BTRFS_SEND_FLAG_NO_FILE_DATA
) {
4730 ret
= send_update_extent(sctx
, offset
, len
);
4734 if (l
> BTRFS_SEND_READ_SIZE
)
4735 l
= BTRFS_SEND_READ_SIZE
;
4736 ret
= send_write(sctx
, pos
+ offset
, l
);
4749 static int is_extent_unchanged(struct send_ctx
*sctx
,
4750 struct btrfs_path
*left_path
,
4751 struct btrfs_key
*ekey
)
4754 struct btrfs_key key
;
4755 struct btrfs_path
*path
= NULL
;
4756 struct extent_buffer
*eb
;
4758 struct btrfs_key found_key
;
4759 struct btrfs_file_extent_item
*ei
;
4764 u64 left_offset_fixed
;
4772 path
= alloc_path_for_send();
4776 eb
= left_path
->nodes
[0];
4777 slot
= left_path
->slots
[0];
4778 ei
= btrfs_item_ptr(eb
, slot
, struct btrfs_file_extent_item
);
4779 left_type
= btrfs_file_extent_type(eb
, ei
);
4781 if (left_type
!= BTRFS_FILE_EXTENT_REG
) {
4785 left_disknr
= btrfs_file_extent_disk_bytenr(eb
, ei
);
4786 left_len
= btrfs_file_extent_num_bytes(eb
, ei
);
4787 left_offset
= btrfs_file_extent_offset(eb
, ei
);
4788 left_gen
= btrfs_file_extent_generation(eb
, ei
);
4791 * Following comments will refer to these graphics. L is the left
4792 * extents which we are checking at the moment. 1-8 are the right
4793 * extents that we iterate.
4796 * |-1-|-2a-|-3-|-4-|-5-|-6-|
4799 * |--1--|-2b-|...(same as above)
4801 * Alternative situation. Happens on files where extents got split.
4803 * |-----------7-----------|-6-|
4805 * Alternative situation. Happens on files which got larger.
4808 * Nothing follows after 8.
4811 key
.objectid
= ekey
->objectid
;
4812 key
.type
= BTRFS_EXTENT_DATA_KEY
;
4813 key
.offset
= ekey
->offset
;
4814 ret
= btrfs_search_slot_for_read(sctx
->parent_root
, &key
, path
, 0, 0);
4823 * Handle special case where the right side has no extents at all.
4825 eb
= path
->nodes
[0];
4826 slot
= path
->slots
[0];
4827 btrfs_item_key_to_cpu(eb
, &found_key
, slot
);
4828 if (found_key
.objectid
!= key
.objectid
||
4829 found_key
.type
!= key
.type
) {
4830 /* If we're a hole then just pretend nothing changed */
4831 ret
= (left_disknr
) ? 0 : 1;
4836 * We're now on 2a, 2b or 7.
4839 while (key
.offset
< ekey
->offset
+ left_len
) {
4840 ei
= btrfs_item_ptr(eb
, slot
, struct btrfs_file_extent_item
);
4841 right_type
= btrfs_file_extent_type(eb
, ei
);
4842 if (right_type
!= BTRFS_FILE_EXTENT_REG
) {
4847 right_disknr
= btrfs_file_extent_disk_bytenr(eb
, ei
);
4848 right_len
= btrfs_file_extent_num_bytes(eb
, ei
);
4849 right_offset
= btrfs_file_extent_offset(eb
, ei
);
4850 right_gen
= btrfs_file_extent_generation(eb
, ei
);
4853 * Are we at extent 8? If yes, we know the extent is changed.
4854 * This may only happen on the first iteration.
4856 if (found_key
.offset
+ right_len
<= ekey
->offset
) {
4857 /* If we're a hole just pretend nothing changed */
4858 ret
= (left_disknr
) ? 0 : 1;
4862 left_offset_fixed
= left_offset
;
4863 if (key
.offset
< ekey
->offset
) {
4864 /* Fix the right offset for 2a and 7. */
4865 right_offset
+= ekey
->offset
- key
.offset
;
4867 /* Fix the left offset for all behind 2a and 2b */
4868 left_offset_fixed
+= key
.offset
- ekey
->offset
;
4872 * Check if we have the same extent.
4874 if (left_disknr
!= right_disknr
||
4875 left_offset_fixed
!= right_offset
||
4876 left_gen
!= right_gen
) {
4882 * Go to the next extent.
4884 ret
= btrfs_next_item(sctx
->parent_root
, path
);
4888 eb
= path
->nodes
[0];
4889 slot
= path
->slots
[0];
4890 btrfs_item_key_to_cpu(eb
, &found_key
, slot
);
4892 if (ret
|| found_key
.objectid
!= key
.objectid
||
4893 found_key
.type
!= key
.type
) {
4894 key
.offset
+= right_len
;
4897 if (found_key
.offset
!= key
.offset
+ right_len
) {
4905 * We're now behind the left extent (treat as unchanged) or at the end
4906 * of the right side (treat as changed).
4908 if (key
.offset
>= ekey
->offset
+ left_len
)
4915 btrfs_free_path(path
);
4919 static int get_last_extent(struct send_ctx
*sctx
, u64 offset
)
4921 struct btrfs_path
*path
;
4922 struct btrfs_root
*root
= sctx
->send_root
;
4923 struct btrfs_file_extent_item
*fi
;
4924 struct btrfs_key key
;
4929 path
= alloc_path_for_send();
4933 sctx
->cur_inode_last_extent
= 0;
4935 key
.objectid
= sctx
->cur_ino
;
4936 key
.type
= BTRFS_EXTENT_DATA_KEY
;
4937 key
.offset
= offset
;
4938 ret
= btrfs_search_slot_for_read(root
, &key
, path
, 0, 1);
4942 btrfs_item_key_to_cpu(path
->nodes
[0], &key
, path
->slots
[0]);
4943 if (key
.objectid
!= sctx
->cur_ino
|| key
.type
!= BTRFS_EXTENT_DATA_KEY
)
4946 fi
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
4947 struct btrfs_file_extent_item
);
4948 type
= btrfs_file_extent_type(path
->nodes
[0], fi
);
4949 if (type
== BTRFS_FILE_EXTENT_INLINE
) {
4950 u64 size
= btrfs_file_extent_inline_len(path
->nodes
[0],
4951 path
->slots
[0], fi
);
4952 extent_end
= ALIGN(key
.offset
+ size
,
4953 sctx
->send_root
->sectorsize
);
4955 extent_end
= key
.offset
+
4956 btrfs_file_extent_num_bytes(path
->nodes
[0], fi
);
4958 sctx
->cur_inode_last_extent
= extent_end
;
4960 btrfs_free_path(path
);
4964 static int maybe_send_hole(struct send_ctx
*sctx
, struct btrfs_path
*path
,
4965 struct btrfs_key
*key
)
4967 struct btrfs_file_extent_item
*fi
;
4972 if (sctx
->cur_ino
!= key
->objectid
|| !need_send_hole(sctx
))
4975 if (sctx
->cur_inode_last_extent
== (u64
)-1) {
4976 ret
= get_last_extent(sctx
, key
->offset
- 1);
4981 fi
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
4982 struct btrfs_file_extent_item
);
4983 type
= btrfs_file_extent_type(path
->nodes
[0], fi
);
4984 if (type
== BTRFS_FILE_EXTENT_INLINE
) {
4985 u64 size
= btrfs_file_extent_inline_len(path
->nodes
[0],
4986 path
->slots
[0], fi
);
4987 extent_end
= ALIGN(key
->offset
+ size
,
4988 sctx
->send_root
->sectorsize
);
4990 extent_end
= key
->offset
+
4991 btrfs_file_extent_num_bytes(path
->nodes
[0], fi
);
4994 if (path
->slots
[0] == 0 &&
4995 sctx
->cur_inode_last_extent
< key
->offset
) {
4997 * We might have skipped entire leafs that contained only
4998 * file extent items for our current inode. These leafs have
4999 * a generation number smaller (older) than the one in the
5000 * current leaf and the leaf our last extent came from, and
5001 * are located between these 2 leafs.
5003 ret
= get_last_extent(sctx
, key
->offset
- 1);
5008 if (sctx
->cur_inode_last_extent
< key
->offset
)
5009 ret
= send_hole(sctx
, key
->offset
);
5010 sctx
->cur_inode_last_extent
= extent_end
;
5014 static int process_extent(struct send_ctx
*sctx
,
5015 struct btrfs_path
*path
,
5016 struct btrfs_key
*key
)
5018 struct clone_root
*found_clone
= NULL
;
5021 if (S_ISLNK(sctx
->cur_inode_mode
))
5024 if (sctx
->parent_root
&& !sctx
->cur_inode_new
) {
5025 ret
= is_extent_unchanged(sctx
, path
, key
);
5033 struct btrfs_file_extent_item
*ei
;
5036 ei
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
5037 struct btrfs_file_extent_item
);
5038 type
= btrfs_file_extent_type(path
->nodes
[0], ei
);
5039 if (type
== BTRFS_FILE_EXTENT_PREALLOC
||
5040 type
== BTRFS_FILE_EXTENT_REG
) {
5042 * The send spec does not have a prealloc command yet,
5043 * so just leave a hole for prealloc'ed extents until
5044 * we have enough commands queued up to justify rev'ing
5047 if (type
== BTRFS_FILE_EXTENT_PREALLOC
) {
5052 /* Have a hole, just skip it. */
5053 if (btrfs_file_extent_disk_bytenr(path
->nodes
[0], ei
) == 0) {
5060 ret
= find_extent_clone(sctx
, path
, key
->objectid
, key
->offset
,
5061 sctx
->cur_inode_size
, &found_clone
);
5062 if (ret
!= -ENOENT
&& ret
< 0)
5065 ret
= send_write_or_clone(sctx
, path
, key
, found_clone
);
5069 ret
= maybe_send_hole(sctx
, path
, key
);
5074 static int process_all_extents(struct send_ctx
*sctx
)
5077 struct btrfs_root
*root
;
5078 struct btrfs_path
*path
;
5079 struct btrfs_key key
;
5080 struct btrfs_key found_key
;
5081 struct extent_buffer
*eb
;
5084 root
= sctx
->send_root
;
5085 path
= alloc_path_for_send();
5089 key
.objectid
= sctx
->cmp_key
->objectid
;
5090 key
.type
= BTRFS_EXTENT_DATA_KEY
;
5092 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
5097 eb
= path
->nodes
[0];
5098 slot
= path
->slots
[0];
5100 if (slot
>= btrfs_header_nritems(eb
)) {
5101 ret
= btrfs_next_leaf(root
, path
);
5104 } else if (ret
> 0) {
5111 btrfs_item_key_to_cpu(eb
, &found_key
, slot
);
5113 if (found_key
.objectid
!= key
.objectid
||
5114 found_key
.type
!= key
.type
) {
5119 ret
= process_extent(sctx
, path
, &found_key
);
5127 btrfs_free_path(path
);
5131 static int process_recorded_refs_if_needed(struct send_ctx
*sctx
, int at_end
,
5133 int *refs_processed
)
5137 if (sctx
->cur_ino
== 0)
5139 if (!at_end
&& sctx
->cur_ino
== sctx
->cmp_key
->objectid
&&
5140 sctx
->cmp_key
->type
<= BTRFS_INODE_EXTREF_KEY
)
5142 if (list_empty(&sctx
->new_refs
) && list_empty(&sctx
->deleted_refs
))
5145 ret
= process_recorded_refs(sctx
, pending_move
);
5149 *refs_processed
= 1;
5154 static int finish_inode_if_needed(struct send_ctx
*sctx
, int at_end
)
5165 int pending_move
= 0;
5166 int refs_processed
= 0;
5168 ret
= process_recorded_refs_if_needed(sctx
, at_end
, &pending_move
,
5174 * We have processed the refs and thus need to advance send_progress.
5175 * Now, calls to get_cur_xxx will take the updated refs of the current
5176 * inode into account.
5178 * On the other hand, if our current inode is a directory and couldn't
5179 * be moved/renamed because its parent was renamed/moved too and it has
5180 * a higher inode number, we can only move/rename our current inode
5181 * after we moved/renamed its parent. Therefore in this case operate on
5182 * the old path (pre move/rename) of our current inode, and the
5183 * move/rename will be performed later.
5185 if (refs_processed
&& !pending_move
)
5186 sctx
->send_progress
= sctx
->cur_ino
+ 1;
5188 if (sctx
->cur_ino
== 0 || sctx
->cur_inode_deleted
)
5190 if (!at_end
&& sctx
->cmp_key
->objectid
== sctx
->cur_ino
)
5193 ret
= get_inode_info(sctx
->send_root
, sctx
->cur_ino
, NULL
, NULL
,
5194 &left_mode
, &left_uid
, &left_gid
, NULL
);
5198 if (!sctx
->parent_root
|| sctx
->cur_inode_new
) {
5200 if (!S_ISLNK(sctx
->cur_inode_mode
))
5203 ret
= get_inode_info(sctx
->parent_root
, sctx
->cur_ino
,
5204 NULL
, NULL
, &right_mode
, &right_uid
,
5209 if (left_uid
!= right_uid
|| left_gid
!= right_gid
)
5211 if (!S_ISLNK(sctx
->cur_inode_mode
) && left_mode
!= right_mode
)
5215 if (S_ISREG(sctx
->cur_inode_mode
)) {
5216 if (need_send_hole(sctx
)) {
5217 if (sctx
->cur_inode_last_extent
== (u64
)-1 ||
5218 sctx
->cur_inode_last_extent
<
5219 sctx
->cur_inode_size
) {
5220 ret
= get_last_extent(sctx
, (u64
)-1);
5224 if (sctx
->cur_inode_last_extent
<
5225 sctx
->cur_inode_size
) {
5226 ret
= send_hole(sctx
, sctx
->cur_inode_size
);
5231 ret
= send_truncate(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
,
5232 sctx
->cur_inode_size
);
5238 ret
= send_chown(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
,
5239 left_uid
, left_gid
);
5244 ret
= send_chmod(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
,
5251 * If other directory inodes depended on our current directory
5252 * inode's move/rename, now do their move/rename operations.
5254 if (!is_waiting_for_move(sctx
, sctx
->cur_ino
)) {
5255 ret
= apply_children_dir_moves(sctx
);
5259 * Need to send that every time, no matter if it actually
5260 * changed between the two trees as we have done changes to
5261 * the inode before. If our inode is a directory and it's
5262 * waiting to be moved/renamed, we will send its utimes when
5263 * it's moved/renamed, therefore we don't need to do it here.
5265 sctx
->send_progress
= sctx
->cur_ino
+ 1;
5266 ret
= send_utimes(sctx
, sctx
->cur_ino
, sctx
->cur_inode_gen
);
5275 static int changed_inode(struct send_ctx
*sctx
,
5276 enum btrfs_compare_tree_result result
)
5279 struct btrfs_key
*key
= sctx
->cmp_key
;
5280 struct btrfs_inode_item
*left_ii
= NULL
;
5281 struct btrfs_inode_item
*right_ii
= NULL
;
5285 sctx
->cur_ino
= key
->objectid
;
5286 sctx
->cur_inode_new_gen
= 0;
5287 sctx
->cur_inode_last_extent
= (u64
)-1;
5290 * Set send_progress to current inode. This will tell all get_cur_xxx
5291 * functions that the current inode's refs are not updated yet. Later,
5292 * when process_recorded_refs is finished, it is set to cur_ino + 1.
5294 sctx
->send_progress
= sctx
->cur_ino
;
5296 if (result
== BTRFS_COMPARE_TREE_NEW
||
5297 result
== BTRFS_COMPARE_TREE_CHANGED
) {
5298 left_ii
= btrfs_item_ptr(sctx
->left_path
->nodes
[0],
5299 sctx
->left_path
->slots
[0],
5300 struct btrfs_inode_item
);
5301 left_gen
= btrfs_inode_generation(sctx
->left_path
->nodes
[0],
5304 right_ii
= btrfs_item_ptr(sctx
->right_path
->nodes
[0],
5305 sctx
->right_path
->slots
[0],
5306 struct btrfs_inode_item
);
5307 right_gen
= btrfs_inode_generation(sctx
->right_path
->nodes
[0],
5310 if (result
== BTRFS_COMPARE_TREE_CHANGED
) {
5311 right_ii
= btrfs_item_ptr(sctx
->right_path
->nodes
[0],
5312 sctx
->right_path
->slots
[0],
5313 struct btrfs_inode_item
);
5315 right_gen
= btrfs_inode_generation(sctx
->right_path
->nodes
[0],
5319 * The cur_ino = root dir case is special here. We can't treat
5320 * the inode as deleted+reused because it would generate a
5321 * stream that tries to delete/mkdir the root dir.
5323 if (left_gen
!= right_gen
&&
5324 sctx
->cur_ino
!= BTRFS_FIRST_FREE_OBJECTID
)
5325 sctx
->cur_inode_new_gen
= 1;
5328 if (result
== BTRFS_COMPARE_TREE_NEW
) {
5329 sctx
->cur_inode_gen
= left_gen
;
5330 sctx
->cur_inode_new
= 1;
5331 sctx
->cur_inode_deleted
= 0;
5332 sctx
->cur_inode_size
= btrfs_inode_size(
5333 sctx
->left_path
->nodes
[0], left_ii
);
5334 sctx
->cur_inode_mode
= btrfs_inode_mode(
5335 sctx
->left_path
->nodes
[0], left_ii
);
5336 sctx
->cur_inode_rdev
= btrfs_inode_rdev(
5337 sctx
->left_path
->nodes
[0], left_ii
);
5338 if (sctx
->cur_ino
!= BTRFS_FIRST_FREE_OBJECTID
)
5339 ret
= send_create_inode_if_needed(sctx
);
5340 } else if (result
== BTRFS_COMPARE_TREE_DELETED
) {
5341 sctx
->cur_inode_gen
= right_gen
;
5342 sctx
->cur_inode_new
= 0;
5343 sctx
->cur_inode_deleted
= 1;
5344 sctx
->cur_inode_size
= btrfs_inode_size(
5345 sctx
->right_path
->nodes
[0], right_ii
);
5346 sctx
->cur_inode_mode
= btrfs_inode_mode(
5347 sctx
->right_path
->nodes
[0], right_ii
);
5348 } else if (result
== BTRFS_COMPARE_TREE_CHANGED
) {
5350 * We need to do some special handling in case the inode was
5351 * reported as changed with a changed generation number. This
5352 * means that the original inode was deleted and new inode
5353 * reused the same inum. So we have to treat the old inode as
5354 * deleted and the new one as new.
5356 if (sctx
->cur_inode_new_gen
) {
5358 * First, process the inode as if it was deleted.
5360 sctx
->cur_inode_gen
= right_gen
;
5361 sctx
->cur_inode_new
= 0;
5362 sctx
->cur_inode_deleted
= 1;
5363 sctx
->cur_inode_size
= btrfs_inode_size(
5364 sctx
->right_path
->nodes
[0], right_ii
);
5365 sctx
->cur_inode_mode
= btrfs_inode_mode(
5366 sctx
->right_path
->nodes
[0], right_ii
);
5367 ret
= process_all_refs(sctx
,
5368 BTRFS_COMPARE_TREE_DELETED
);
5373 * Now process the inode as if it was new.
5375 sctx
->cur_inode_gen
= left_gen
;
5376 sctx
->cur_inode_new
= 1;
5377 sctx
->cur_inode_deleted
= 0;
5378 sctx
->cur_inode_size
= btrfs_inode_size(
5379 sctx
->left_path
->nodes
[0], left_ii
);
5380 sctx
->cur_inode_mode
= btrfs_inode_mode(
5381 sctx
->left_path
->nodes
[0], left_ii
);
5382 sctx
->cur_inode_rdev
= btrfs_inode_rdev(
5383 sctx
->left_path
->nodes
[0], left_ii
);
5384 ret
= send_create_inode_if_needed(sctx
);
5388 ret
= process_all_refs(sctx
, BTRFS_COMPARE_TREE_NEW
);
5392 * Advance send_progress now as we did not get into
5393 * process_recorded_refs_if_needed in the new_gen case.
5395 sctx
->send_progress
= sctx
->cur_ino
+ 1;
5398 * Now process all extents and xattrs of the inode as if
5399 * they were all new.
5401 ret
= process_all_extents(sctx
);
5404 ret
= process_all_new_xattrs(sctx
);
5408 sctx
->cur_inode_gen
= left_gen
;
5409 sctx
->cur_inode_new
= 0;
5410 sctx
->cur_inode_new_gen
= 0;
5411 sctx
->cur_inode_deleted
= 0;
5412 sctx
->cur_inode_size
= btrfs_inode_size(
5413 sctx
->left_path
->nodes
[0], left_ii
);
5414 sctx
->cur_inode_mode
= btrfs_inode_mode(
5415 sctx
->left_path
->nodes
[0], left_ii
);
5424 * We have to process new refs before deleted refs, but compare_trees gives us
5425 * the new and deleted refs mixed. To fix this, we record the new/deleted refs
5426 * first and later process them in process_recorded_refs.
5427 * For the cur_inode_new_gen case, we skip recording completely because
5428 * changed_inode did already initiate processing of refs. The reason for this is
5429 * that in this case, compare_tree actually compares the refs of 2 different
5430 * inodes. To fix this, process_all_refs is used in changed_inode to handle all
5431 * refs of the right tree as deleted and all refs of the left tree as new.
5433 static int changed_ref(struct send_ctx
*sctx
,
5434 enum btrfs_compare_tree_result result
)
5438 BUG_ON(sctx
->cur_ino
!= sctx
->cmp_key
->objectid
);
5440 if (!sctx
->cur_inode_new_gen
&&
5441 sctx
->cur_ino
!= BTRFS_FIRST_FREE_OBJECTID
) {
5442 if (result
== BTRFS_COMPARE_TREE_NEW
)
5443 ret
= record_new_ref(sctx
);
5444 else if (result
== BTRFS_COMPARE_TREE_DELETED
)
5445 ret
= record_deleted_ref(sctx
);
5446 else if (result
== BTRFS_COMPARE_TREE_CHANGED
)
5447 ret
= record_changed_ref(sctx
);
5454 * Process new/deleted/changed xattrs. We skip processing in the
5455 * cur_inode_new_gen case because changed_inode did already initiate processing
5456 * of xattrs. The reason is the same as in changed_ref
5458 static int changed_xattr(struct send_ctx
*sctx
,
5459 enum btrfs_compare_tree_result result
)
5463 BUG_ON(sctx
->cur_ino
!= sctx
->cmp_key
->objectid
);
5465 if (!sctx
->cur_inode_new_gen
&& !sctx
->cur_inode_deleted
) {
5466 if (result
== BTRFS_COMPARE_TREE_NEW
)
5467 ret
= process_new_xattr(sctx
);
5468 else if (result
== BTRFS_COMPARE_TREE_DELETED
)
5469 ret
= process_deleted_xattr(sctx
);
5470 else if (result
== BTRFS_COMPARE_TREE_CHANGED
)
5471 ret
= process_changed_xattr(sctx
);
5478 * Process new/deleted/changed extents. We skip processing in the
5479 * cur_inode_new_gen case because changed_inode did already initiate processing
5480 * of extents. The reason is the same as in changed_ref
5482 static int changed_extent(struct send_ctx
*sctx
,
5483 enum btrfs_compare_tree_result result
)
5487 BUG_ON(sctx
->cur_ino
!= sctx
->cmp_key
->objectid
);
5489 if (!sctx
->cur_inode_new_gen
&& !sctx
->cur_inode_deleted
) {
5490 if (result
!= BTRFS_COMPARE_TREE_DELETED
)
5491 ret
= process_extent(sctx
, sctx
->left_path
,
5498 static int dir_changed(struct send_ctx
*sctx
, u64 dir
)
5500 u64 orig_gen
, new_gen
;
5503 ret
= get_inode_info(sctx
->send_root
, dir
, NULL
, &new_gen
, NULL
, NULL
,
5508 ret
= get_inode_info(sctx
->parent_root
, dir
, NULL
, &orig_gen
, NULL
,
5513 return (orig_gen
!= new_gen
) ? 1 : 0;
5516 static int compare_refs(struct send_ctx
*sctx
, struct btrfs_path
*path
,
5517 struct btrfs_key
*key
)
5519 struct btrfs_inode_extref
*extref
;
5520 struct extent_buffer
*leaf
;
5521 u64 dirid
= 0, last_dirid
= 0;
5528 /* Easy case, just check this one dirid */
5529 if (key
->type
== BTRFS_INODE_REF_KEY
) {
5530 dirid
= key
->offset
;
5532 ret
= dir_changed(sctx
, dirid
);
5536 leaf
= path
->nodes
[0];
5537 item_size
= btrfs_item_size_nr(leaf
, path
->slots
[0]);
5538 ptr
= btrfs_item_ptr_offset(leaf
, path
->slots
[0]);
5539 while (cur_offset
< item_size
) {
5540 extref
= (struct btrfs_inode_extref
*)(ptr
+
5542 dirid
= btrfs_inode_extref_parent(leaf
, extref
);
5543 ref_name_len
= btrfs_inode_extref_name_len(leaf
, extref
);
5544 cur_offset
+= ref_name_len
+ sizeof(*extref
);
5545 if (dirid
== last_dirid
)
5547 ret
= dir_changed(sctx
, dirid
);
5557 * Updates compare related fields in sctx and simply forwards to the actual
5558 * changed_xxx functions.
5560 static int changed_cb(struct btrfs_root
*left_root
,
5561 struct btrfs_root
*right_root
,
5562 struct btrfs_path
*left_path
,
5563 struct btrfs_path
*right_path
,
5564 struct btrfs_key
*key
,
5565 enum btrfs_compare_tree_result result
,
5569 struct send_ctx
*sctx
= ctx
;
5571 if (result
== BTRFS_COMPARE_TREE_SAME
) {
5572 if (key
->type
== BTRFS_INODE_REF_KEY
||
5573 key
->type
== BTRFS_INODE_EXTREF_KEY
) {
5574 ret
= compare_refs(sctx
, left_path
, key
);
5579 } else if (key
->type
== BTRFS_EXTENT_DATA_KEY
) {
5580 return maybe_send_hole(sctx
, left_path
, key
);
5584 result
= BTRFS_COMPARE_TREE_CHANGED
;
5588 sctx
->left_path
= left_path
;
5589 sctx
->right_path
= right_path
;
5590 sctx
->cmp_key
= key
;
5592 ret
= finish_inode_if_needed(sctx
, 0);
5596 /* Ignore non-FS objects */
5597 if (key
->objectid
== BTRFS_FREE_INO_OBJECTID
||
5598 key
->objectid
== BTRFS_FREE_SPACE_OBJECTID
)
5601 if (key
->type
== BTRFS_INODE_ITEM_KEY
)
5602 ret
= changed_inode(sctx
, result
);
5603 else if (key
->type
== BTRFS_INODE_REF_KEY
||
5604 key
->type
== BTRFS_INODE_EXTREF_KEY
)
5605 ret
= changed_ref(sctx
, result
);
5606 else if (key
->type
== BTRFS_XATTR_ITEM_KEY
)
5607 ret
= changed_xattr(sctx
, result
);
5608 else if (key
->type
== BTRFS_EXTENT_DATA_KEY
)
5609 ret
= changed_extent(sctx
, result
);
5615 static int full_send_tree(struct send_ctx
*sctx
)
5618 struct btrfs_root
*send_root
= sctx
->send_root
;
5619 struct btrfs_key key
;
5620 struct btrfs_key found_key
;
5621 struct btrfs_path
*path
;
5622 struct extent_buffer
*eb
;
5625 path
= alloc_path_for_send();
5629 key
.objectid
= BTRFS_FIRST_FREE_OBJECTID
;
5630 key
.type
= BTRFS_INODE_ITEM_KEY
;
5633 ret
= btrfs_search_slot_for_read(send_root
, &key
, path
, 1, 0);
5640 eb
= path
->nodes
[0];
5641 slot
= path
->slots
[0];
5642 btrfs_item_key_to_cpu(eb
, &found_key
, slot
);
5644 ret
= changed_cb(send_root
, NULL
, path
, NULL
,
5645 &found_key
, BTRFS_COMPARE_TREE_NEW
, sctx
);
5649 key
.objectid
= found_key
.objectid
;
5650 key
.type
= found_key
.type
;
5651 key
.offset
= found_key
.offset
+ 1;
5653 ret
= btrfs_next_item(send_root
, path
);
5663 ret
= finish_inode_if_needed(sctx
, 1);
5666 btrfs_free_path(path
);
5670 static int send_subvol(struct send_ctx
*sctx
)
5674 if (!(sctx
->flags
& BTRFS_SEND_FLAG_OMIT_STREAM_HEADER
)) {
5675 ret
= send_header(sctx
);
5680 ret
= send_subvol_begin(sctx
);
5684 if (sctx
->parent_root
) {
5685 ret
= btrfs_compare_trees(sctx
->send_root
, sctx
->parent_root
,
5689 ret
= finish_inode_if_needed(sctx
, 1);
5693 ret
= full_send_tree(sctx
);
5699 free_recorded_refs(sctx
);
5704 * If orphan cleanup did remove any orphans from a root, it means the tree
5705 * was modified and therefore the commit root is not the same as the current
5706 * root anymore. This is a problem, because send uses the commit root and
5707 * therefore can see inode items that don't exist in the current root anymore,
5708 * and for example make calls to btrfs_iget, which will do tree lookups based
5709 * on the current root and not on the commit root. Those lookups will fail,
5710 * returning a -ESTALE error, and making send fail with that error. So make
5711 * sure a send does not see any orphans we have just removed, and that it will
5712 * see the same inodes regardless of whether a transaction commit happened
5713 * before it started (meaning that the commit root will be the same as the
5714 * current root) or not.
5716 static int ensure_commit_roots_uptodate(struct send_ctx
*sctx
)
5719 struct btrfs_trans_handle
*trans
= NULL
;
5722 if (sctx
->parent_root
&&
5723 sctx
->parent_root
->node
!= sctx
->parent_root
->commit_root
)
5726 for (i
= 0; i
< sctx
->clone_roots_cnt
; i
++)
5727 if (sctx
->clone_roots
[i
].root
->node
!=
5728 sctx
->clone_roots
[i
].root
->commit_root
)
5732 return btrfs_end_transaction(trans
, sctx
->send_root
);
5737 /* Use any root, all fs roots will get their commit roots updated. */
5739 trans
= btrfs_join_transaction(sctx
->send_root
);
5741 return PTR_ERR(trans
);
5745 return btrfs_commit_transaction(trans
, sctx
->send_root
);
5748 static void btrfs_root_dec_send_in_progress(struct btrfs_root
* root
)
5750 spin_lock(&root
->root_item_lock
);
5751 root
->send_in_progress
--;
5753 * Not much left to do, we don't know why it's unbalanced and
5754 * can't blindly reset it to 0.
5756 if (root
->send_in_progress
< 0)
5757 btrfs_err(root
->fs_info
,
5758 "send_in_progres unbalanced %d root %llu",
5759 root
->send_in_progress
, root
->root_key
.objectid
);
5760 spin_unlock(&root
->root_item_lock
);
5763 long btrfs_ioctl_send(struct file
*mnt_file
, void __user
*arg_
)
5766 struct btrfs_root
*send_root
;
5767 struct btrfs_root
*clone_root
;
5768 struct btrfs_fs_info
*fs_info
;
5769 struct btrfs_ioctl_send_args
*arg
= NULL
;
5770 struct btrfs_key key
;
5771 struct send_ctx
*sctx
= NULL
;
5773 u64
*clone_sources_tmp
= NULL
;
5774 int clone_sources_to_rollback
= 0;
5775 int sort_clone_roots
= 0;
5778 if (!capable(CAP_SYS_ADMIN
))
5781 send_root
= BTRFS_I(file_inode(mnt_file
))->root
;
5782 fs_info
= send_root
->fs_info
;
5785 * The subvolume must remain read-only during send, protect against
5786 * making it RW. This also protects against deletion.
5788 spin_lock(&send_root
->root_item_lock
);
5789 send_root
->send_in_progress
++;
5790 spin_unlock(&send_root
->root_item_lock
);
5793 * This is done when we lookup the root, it should already be complete
5794 * by the time we get here.
5796 WARN_ON(send_root
->orphan_cleanup_state
!= ORPHAN_CLEANUP_DONE
);
5799 * Userspace tools do the checks and warn the user if it's
5802 if (!btrfs_root_readonly(send_root
)) {
5807 arg
= memdup_user(arg_
, sizeof(*arg
));
5814 if (!access_ok(VERIFY_READ
, arg
->clone_sources
,
5815 sizeof(*arg
->clone_sources
) *
5816 arg
->clone_sources_count
)) {
5821 if (arg
->flags
& ~BTRFS_SEND_FLAG_MASK
) {
5826 sctx
= kzalloc(sizeof(struct send_ctx
), GFP_NOFS
);
5832 INIT_LIST_HEAD(&sctx
->new_refs
);
5833 INIT_LIST_HEAD(&sctx
->deleted_refs
);
5834 INIT_RADIX_TREE(&sctx
->name_cache
, GFP_NOFS
);
5835 INIT_LIST_HEAD(&sctx
->name_cache_list
);
5837 sctx
->flags
= arg
->flags
;
5839 sctx
->send_filp
= fget(arg
->send_fd
);
5840 if (!sctx
->send_filp
) {
5845 sctx
->send_root
= send_root
;
5847 * Unlikely but possible, if the subvolume is marked for deletion but
5848 * is slow to remove the directory entry, send can still be started
5850 if (btrfs_root_dead(sctx
->send_root
)) {
5855 sctx
->clone_roots_cnt
= arg
->clone_sources_count
;
5857 sctx
->send_max_size
= BTRFS_SEND_BUF_SIZE
;
5858 sctx
->send_buf
= vmalloc(sctx
->send_max_size
);
5859 if (!sctx
->send_buf
) {
5864 sctx
->read_buf
= vmalloc(BTRFS_SEND_READ_SIZE
);
5865 if (!sctx
->read_buf
) {
5870 sctx
->pending_dir_moves
= RB_ROOT
;
5871 sctx
->waiting_dir_moves
= RB_ROOT
;
5872 sctx
->orphan_dirs
= RB_ROOT
;
5874 sctx
->clone_roots
= vzalloc(sizeof(struct clone_root
) *
5875 (arg
->clone_sources_count
+ 1));
5876 if (!sctx
->clone_roots
) {
5881 if (arg
->clone_sources_count
) {
5882 clone_sources_tmp
= vmalloc(arg
->clone_sources_count
*
5883 sizeof(*arg
->clone_sources
));
5884 if (!clone_sources_tmp
) {
5889 ret
= copy_from_user(clone_sources_tmp
, arg
->clone_sources
,
5890 arg
->clone_sources_count
*
5891 sizeof(*arg
->clone_sources
));
5897 for (i
= 0; i
< arg
->clone_sources_count
; i
++) {
5898 key
.objectid
= clone_sources_tmp
[i
];
5899 key
.type
= BTRFS_ROOT_ITEM_KEY
;
5900 key
.offset
= (u64
)-1;
5902 index
= srcu_read_lock(&fs_info
->subvol_srcu
);
5904 clone_root
= btrfs_read_fs_root_no_name(fs_info
, &key
);
5905 if (IS_ERR(clone_root
)) {
5906 srcu_read_unlock(&fs_info
->subvol_srcu
, index
);
5907 ret
= PTR_ERR(clone_root
);
5910 spin_lock(&clone_root
->root_item_lock
);
5911 if (!btrfs_root_readonly(clone_root
) ||
5912 btrfs_root_dead(clone_root
)) {
5913 spin_unlock(&clone_root
->root_item_lock
);
5914 srcu_read_unlock(&fs_info
->subvol_srcu
, index
);
5918 clone_root
->send_in_progress
++;
5919 spin_unlock(&clone_root
->root_item_lock
);
5920 srcu_read_unlock(&fs_info
->subvol_srcu
, index
);
5922 sctx
->clone_roots
[i
].root
= clone_root
;
5923 clone_sources_to_rollback
= i
+ 1;
5925 vfree(clone_sources_tmp
);
5926 clone_sources_tmp
= NULL
;
5929 if (arg
->parent_root
) {
5930 key
.objectid
= arg
->parent_root
;
5931 key
.type
= BTRFS_ROOT_ITEM_KEY
;
5932 key
.offset
= (u64
)-1;
5934 index
= srcu_read_lock(&fs_info
->subvol_srcu
);
5936 sctx
->parent_root
= btrfs_read_fs_root_no_name(fs_info
, &key
);
5937 if (IS_ERR(sctx
->parent_root
)) {
5938 srcu_read_unlock(&fs_info
->subvol_srcu
, index
);
5939 ret
= PTR_ERR(sctx
->parent_root
);
5943 spin_lock(&sctx
->parent_root
->root_item_lock
);
5944 sctx
->parent_root
->send_in_progress
++;
5945 if (!btrfs_root_readonly(sctx
->parent_root
) ||
5946 btrfs_root_dead(sctx
->parent_root
)) {
5947 spin_unlock(&sctx
->parent_root
->root_item_lock
);
5948 srcu_read_unlock(&fs_info
->subvol_srcu
, index
);
5952 spin_unlock(&sctx
->parent_root
->root_item_lock
);
5954 srcu_read_unlock(&fs_info
->subvol_srcu
, index
);
5958 * Clones from send_root are allowed, but only if the clone source
5959 * is behind the current send position. This is checked while searching
5960 * for possible clone sources.
5962 sctx
->clone_roots
[sctx
->clone_roots_cnt
++].root
= sctx
->send_root
;
5964 /* We do a bsearch later */
5965 sort(sctx
->clone_roots
, sctx
->clone_roots_cnt
,
5966 sizeof(*sctx
->clone_roots
), __clone_root_cmp_sort
,
5968 sort_clone_roots
= 1;
5970 ret
= ensure_commit_roots_uptodate(sctx
);
5974 current
->journal_info
= BTRFS_SEND_TRANS_STUB
;
5975 ret
= send_subvol(sctx
);
5976 current
->journal_info
= NULL
;
5980 if (!(sctx
->flags
& BTRFS_SEND_FLAG_OMIT_END_CMD
)) {
5981 ret
= begin_cmd(sctx
, BTRFS_SEND_C_END
);
5984 ret
= send_cmd(sctx
);
5990 WARN_ON(sctx
&& !ret
&& !RB_EMPTY_ROOT(&sctx
->pending_dir_moves
));
5991 while (sctx
&& !RB_EMPTY_ROOT(&sctx
->pending_dir_moves
)) {
5993 struct pending_dir_move
*pm
;
5995 n
= rb_first(&sctx
->pending_dir_moves
);
5996 pm
= rb_entry(n
, struct pending_dir_move
, node
);
5997 while (!list_empty(&pm
->list
)) {
5998 struct pending_dir_move
*pm2
;
6000 pm2
= list_first_entry(&pm
->list
,
6001 struct pending_dir_move
, list
);
6002 free_pending_move(sctx
, pm2
);
6004 free_pending_move(sctx
, pm
);
6007 WARN_ON(sctx
&& !ret
&& !RB_EMPTY_ROOT(&sctx
->waiting_dir_moves
));
6008 while (sctx
&& !RB_EMPTY_ROOT(&sctx
->waiting_dir_moves
)) {
6010 struct waiting_dir_move
*dm
;
6012 n
= rb_first(&sctx
->waiting_dir_moves
);
6013 dm
= rb_entry(n
, struct waiting_dir_move
, node
);
6014 rb_erase(&dm
->node
, &sctx
->waiting_dir_moves
);
6018 WARN_ON(sctx
&& !ret
&& !RB_EMPTY_ROOT(&sctx
->orphan_dirs
));
6019 while (sctx
&& !RB_EMPTY_ROOT(&sctx
->orphan_dirs
)) {
6021 struct orphan_dir_info
*odi
;
6023 n
= rb_first(&sctx
->orphan_dirs
);
6024 odi
= rb_entry(n
, struct orphan_dir_info
, node
);
6025 free_orphan_dir_info(sctx
, odi
);
6028 if (sort_clone_roots
) {
6029 for (i
= 0; i
< sctx
->clone_roots_cnt
; i
++)
6030 btrfs_root_dec_send_in_progress(
6031 sctx
->clone_roots
[i
].root
);
6033 for (i
= 0; sctx
&& i
< clone_sources_to_rollback
; i
++)
6034 btrfs_root_dec_send_in_progress(
6035 sctx
->clone_roots
[i
].root
);
6037 btrfs_root_dec_send_in_progress(send_root
);
6039 if (sctx
&& !IS_ERR_OR_NULL(sctx
->parent_root
))
6040 btrfs_root_dec_send_in_progress(sctx
->parent_root
);
6043 vfree(clone_sources_tmp
);
6046 if (sctx
->send_filp
)
6047 fput(sctx
->send_filp
);
6049 vfree(sctx
->clone_roots
);
6050 vfree(sctx
->send_buf
);
6051 vfree(sctx
->read_buf
);
6053 name_cache_free(sctx
);