Presently btrfs send/receive does not propagate inode attribute flags;
all chattr operations are effectively discarded upon transmission.
This patch adds kernel support for inode attribute flags. Userspace
support can be found under the commit:
btrfs-progs: add chattr support for send/receive
An associated xfstest can be found at:
btrfs: add verify chattr support for send/receive test
A caveat is that a user with an updated kernel (aware of chattrs) and an
older version of btrfs-progs (unaware of chattrs) will fail to receive
if a chattr is included in the send stream.
Signed-off-by: Howard McLauchlan <hmclauch...@fb.com>
---
Based on 4.17-rc1
fs/btrfs/ctree.h | 2 +
fs/btrfs/ioctl.c | 2 +-
fs/btrfs/send.c | 176 +++++++++++++++++++++++++++++++++++++++--------
fs/btrfs/send.h | 2 +
4 files changed, 154 insertions(+), 28 deletions(-)
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 5474ef14d6e6..a0dc6a8a37eb 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -1436,6 +1436,8 @@ struct btrfs_map_token {
unsigned long offset;
};
+unsigned int btrfs_flags_to_ioctl(unsigned int flags);
+
#define BTRFS_BYTES_TO_BLKS(fs_info, bytes) \
((bytes) >> (fs_info)->sb->s_blocksize_bits)
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 632e26d6f7ce..36ce1e589f9e 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -106,7 +106,7 @@ static unsigned int btrfs_mask_flags(umode_t mode, unsigned
int flags)
/*
* Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl.
*/
-static unsigned int btrfs_flags_to_ioctl(unsigned int flags)
+unsigned int btrfs_flags_to_ioctl(unsigned int flags)
{
unsigned int iflags = 0;
diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
index 221e5cdb060b..da521a5a1843 100644
--- a/fs/btrfs/send.c
+++ b/fs/btrfs/send.c
@@ -101,6 +101,13 @@ struct send_ctx {
u64 cur_inode_last_extent;
u64 cur_inode_next_write_offset;
+ /*
+ * state for chattr purposes
+ */
+ u64 cur_inode_flip_flags;
+ u64 cur_inode_receive_flags;
+ int receive_flags_valid;
+
u64 send_progress;
struct list_head new_refs;
@@ -798,7 +805,7 @@ static int send_rmdir(struct send_ctx *sctx, struct fs_path
*path)
*/
static int __get_inode_info(struct btrfs_root *root, struct btrfs_path *path,
u64 ino, u64 *size, u64 *gen, u64 *mode, u64 *uid,
- u64 *gid, u64 *rdev)
+ u64 *gid, u64 *rdev, u64 *flags)
{
int ret;
struct btrfs_inode_item *ii;
@@ -828,6 +835,8 @@ static int __get_inode_info(struct btrfs_root *root, struct
btrfs_path *path,
*gid = btrfs_inode_gid(path->nodes[0], ii);
if (rdev)
*rdev = btrfs_inode_rdev(path->nodes[0], ii);
+ if (flags)
+ *flags = btrfs_inode_flags(path->nodes[0], ii);
return ret;
}
@@ -835,7 +844,7 @@ static int __get_inode_info(struct btrfs_root *root, struct
btrfs_path *path,
static int get_inode_info(struct btrfs_root *root,
u64 ino, u64 *size, u64 *gen,
u64 *mode, u64 *uid, u64 *gid,
- u64 *rdev)
+ u64 *rdev, u64 *flags)
{
struct btrfs_path *path;
int ret;
@@ -844,7 +853,7 @@ static int get_inode_info(struct btrfs_root *root,
if (!path)
return -ENOMEM;
ret = __get_inode_info(root, path, ino, size, gen, mode, uid, gid,
- rdev);
+ rdev, flags);
btrfs_free_path(path);
return ret;
}
@@ -1233,7 +1242,7 @@ static int __iterate_backrefs(u64 ino, u64 offset, u64
root, void *ctx_)
* accept clones from these extents.
*/
ret = __get_inode_info(found->root, bctx->path, ino, &i_size, NULL,
NULL,
- NULL, NULL, NULL);
+ NULL, NULL, NULL, NULL);
btrfs_release_path(bctx->path);
if (ret < 0)
return ret;
@@ -1593,7 +1602,7 @@ static int get_cur_inode_state(struct send_ctx *sctx, u64
ino, u64 gen)
u64 right_gen;
ret = get_inode_info(sctx->send_root, ino, NULL, &left_gen, NULL, NULL,
- NULL, NULL);
+ NULL, NULL, NULL);
if (ret < 0 && ret != -ENOENT)
goto out;
left_ret = ret;
@@ -1602,7 +1611,7 @@ static int get_cur_inode_state(struct send_ctx *sctx, u64
ino, u64 gen)
right_ret = -ENOENT;
} else {
ret = get_inode_info(sctx->parent_root, ino, NULL, &right_gen,
- NULL, NULL, NULL, NULL);
+ NULL, NULL, NULL, NULL, NULL);
if (ret < 0 && ret != -ENOENT)
goto out;
right_ret = ret;
@@ -1771,7 +1780,7 @@ static int get_first_ref(struct btrfs_root *root, u64 ino,
if (dir_gen) {
ret = get_inode_info(root, parent_dir, NULL, dir_gen, NULL,
- NULL, NULL, NULL);
+ NULL, NULL, NULL, NULL);
if (ret < 0)
goto out;
}
@@ -1844,7 +1853,7 @@ static int will_overwrite_ref(struct send_ctx *sctx, u64
dir, u64 dir_gen,
*/
if (sctx->parent_root && dir != BTRFS_FIRST_FREE_OBJECTID) {
ret = get_inode_info(sctx->parent_root, dir, NULL, &gen, NULL,
- NULL, NULL, NULL);
+ NULL, NULL, NULL, NULL);
if (ret < 0 && ret != -ENOENT)
goto out;
if (ret) {
@@ -1872,7 +1881,7 @@ static int will_overwrite_ref(struct send_ctx *sctx, u64
dir, u64 dir_gen,
if (other_inode > sctx->send_progress ||
is_waiting_for_move(sctx, other_inode)) {
ret = get_inode_info(sctx->parent_root, other_inode, NULL,
- who_gen, who_mode, NULL, NULL, NULL);
+ who_gen, who_mode, NULL, NULL, NULL, NULL);
if (ret < 0)
goto out;
@@ -1912,7 +1921,7 @@ static int did_overwrite_ref(struct send_ctx *sctx,
if (dir != BTRFS_FIRST_FREE_OBJECTID) {
ret = get_inode_info(sctx->send_root, dir, NULL, &gen, NULL,
- NULL, NULL, NULL);
+ NULL, NULL, NULL, NULL);
if (ret < 0 && ret != -ENOENT)
goto out;
if (ret) {
@@ -1935,7 +1944,7 @@ static int did_overwrite_ref(struct send_ctx *sctx,
}
ret = get_inode_info(sctx->send_root, ow_inode, NULL, &gen, NULL, NULL,
- NULL, NULL);
+ NULL, NULL, NULL);
if (ret < 0)
goto out;
@@ -2502,6 +2511,39 @@ static int send_chown(struct send_ctx *sctx, u64 ino,
u64 gen, u64 uid, u64 gid)
return ret;
}
+static int send_chattr(struct send_ctx *sctx, u64 ino, u64 gen, u64 flags)
+{
+ struct btrfs_fs_info *fs_info = sctx->send_root->fs_info;
+ int ret = 0;
+ int __flags;
+ struct fs_path *p;
+
+ __flags = btrfs_flags_to_ioctl(flags);
+
+ btrfs_debug(fs_info, "send_chattr %llu flags=%llu", ino, flags);
+
+ p = fs_path_alloc();
+ if (!p)
+ return -ENOMEM;
+
+ ret = begin_cmd(sctx, BTRFS_SEND_C_CHATTR);
+ if (ret < 0)
+ goto out;
+
+ ret = get_cur_path(sctx, ino, gen, p);
+ if (ret < 0)
+ goto out;
+ TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, p);
+ TLV_PUT_U64(sctx, BTRFS_SEND_A_CHATTR, __flags);
+
+ ret = send_cmd(sctx);
+
+tlv_put_failure:
+out:
+ fs_path_free(p);
+ return ret;
+}
+
static int send_utimes(struct send_ctx *sctx, u64 ino, u64 gen)
{
struct btrfs_fs_info *fs_info = sctx->send_root->fs_info;
@@ -2583,7 +2625,7 @@ static int send_create_inode(struct send_ctx *sctx, u64
ino)
if (ino != sctx->cur_ino) {
ret = get_inode_info(sctx->send_root, ino, NULL, &gen, &mode,
- NULL, NULL, &rdev);
+ NULL, NULL, &rdev, NULL);
if (ret < 0)
goto out;
} else {
@@ -3299,7 +3341,7 @@ static int apply_dir_move(struct send_ctx *sctx, struct
pending_dir_move *pm)
* The parent inode might have been deleted in the send snapshot
*/
ret = get_inode_info(sctx->send_root, cur->dir, NULL,
- NULL, NULL, NULL, NULL, NULL);
+ NULL, NULL, NULL, NULL, NULL, NULL);
if (ret == -ENOENT) {
ret = 0;
continue;
@@ -3469,11 +3511,11 @@ static int wait_for_dest_dir_move(struct send_ctx *sctx,
}
ret = get_inode_info(sctx->parent_root, di_key.objectid, NULL,
- &left_gen, NULL, NULL, NULL, NULL);
+ &left_gen, NULL, NULL, NULL, NULL, NULL);
if (ret < 0)
goto out;
ret = get_inode_info(sctx->send_root, di_key.objectid, NULL,
- &right_gen, NULL, NULL, NULL, NULL);
+ &right_gen, NULL, NULL, NULL, NULL, NULL);
if (ret < 0) {
if (ret == -ENOENT)
ret = 0;
@@ -3617,7 +3659,7 @@ static int is_ancestor(struct btrfs_root *root,
}
ret = get_inode_info(root, parent, NULL, &parent_gen,
- NULL, NULL, NULL, NULL);
+ NULL, NULL, NULL, NULL, NULL);
if (ret < 0)
goto out;
ret = check_ino_in_path(root, ino1, ino1_gen,
@@ -3707,7 +3749,7 @@ static int wait_for_parent_move(struct send_ctx *sctx,
ret = get_inode_info(sctx->parent_root, ino, NULL,
&parent_ino_gen, NULL, NULL, NULL,
- NULL);
+ NULL, NULL);
if (ret < 0)
goto out;
if (ino_gen == parent_ino_gen) {
@@ -4184,7 +4226,7 @@ static int record_ref(struct btrfs_root *root, u64 dir,
struct fs_path *name,
return -ENOMEM;
ret = get_inode_info(root, dir, NULL, &gen, NULL, NULL,
- NULL, NULL);
+ NULL, NULL, NULL);
if (ret < 0)
goto out;
@@ -4272,7 +4314,7 @@ static int __find_iref(int num, u64 dir, int index,
* else matches.
*/
ret = get_inode_info(ctx->root, dir, NULL, &dir_gen, NULL,
- NULL, NULL, NULL);
+ NULL, NULL, NULL, NULL);
if (ret)
return ret;
if (dir_gen != ctx->dir_gen)
@@ -4316,7 +4358,7 @@ static int __record_changed_new_ref(int num, u64 dir, int
index,
struct send_ctx *sctx = ctx;
ret = get_inode_info(sctx->send_root, dir, NULL, &dir_gen, NULL,
- NULL, NULL, NULL);
+ NULL, NULL, NULL, NULL);
if (ret)
return ret;
@@ -4339,7 +4381,7 @@ static int __record_changed_deleted_ref(int num, u64 dir,
int index,
struct send_ctx *sctx = ctx;
ret = get_inode_info(sctx->parent_root, dir, NULL, &dir_gen, NULL,
- NULL, NULL, NULL);
+ NULL, NULL, NULL, NULL);
if (ret)
return ret;
@@ -4915,7 +4957,7 @@ static int send_clone(struct send_ctx *sctx,
if (clone_root->root == sctx->send_root) {
ret = get_inode_info(sctx->send_root, clone_root->ino, NULL,
- &gen, NULL, NULL, NULL, NULL);
+ &gen, NULL, NULL, NULL, NULL, NULL);
if (ret < 0)
goto out;
ret = get_cur_path(sctx, clone_root->ino, gen, p);
@@ -5777,9 +5819,11 @@ static int finish_inode_if_needed(struct send_ctx *sctx,
int at_end)
u64 right_mode;
u64 right_uid;
u64 right_gid;
+ u64 left_flags;
int need_chmod = 0;
int need_chown = 0;
int need_truncate = 1;
+ int need_chattr = 0;
int pending_move = 0;
int refs_processed = 0;
@@ -5787,7 +5831,6 @@ static int finish_inode_if_needed(struct send_ctx *sctx,
int at_end)
&refs_processed);
if (ret < 0)
goto out;
-
/*
* We have processed the refs and thus need to advance send_progress.
* Now, calls to get_cur_xxx will take the updated refs of the current
@@ -5805,11 +5848,67 @@ static int finish_inode_if_needed(struct send_ctx
*sctx, int at_end)
if (sctx->cur_ino == 0 || sctx->cur_inode_deleted)
goto out;
+
+ /*
+ * If possible, we want to know what flags are set for this inode on the
+ * receiving end.
+ */
+ if (sctx->parent_root && !sctx->receive_flags_valid) {
+ ret = get_inode_info(sctx->parent_root, sctx->cur_ino, NULL,
+ NULL, NULL, NULL, NULL, NULL,
+ &sctx->cur_inode_receive_flags);
+ if (ret < 0)
+ goto out;
+ sctx->receive_flags_valid = 1;
+ }
+
+ /*
+ * The change is going to modify data and the inode already exists
+ * !at_end prevents unnecessary chattr.
+ */
+ if (!at_end && sctx->parent_root && !sctx->cur_inode_new &&
+ (sctx->cmp_key->type == BTRFS_EXTENT_DATA_KEY ||
+ sctx->cmp_key->type == BTRFS_XATTR_ITEM_KEY)) {
+
+ ret = get_inode_info(sctx->send_root, sctx->cur_ino, NULL, NULL,
+ NULL, NULL, NULL, NULL, &left_flags);
+ if (ret < 0)
+ goto out;
+ /*
+ * We check against the receive flags first; then check against
+ * the left flags to see if we can save a chattr later on
+ */
+ if (sctx->cur_inode_receive_flags & BTRFS_INODE_IMMUTABLE) {
+ sctx->cur_inode_flip_flags |= (left_flags &
+ BTRFS_INODE_IMMUTABLE);
+ left_flags &= ~BTRFS_INODE_IMMUTABLE;
+ need_chattr = 1;
+ }
+ if (sctx->cur_inode_receive_flags & BTRFS_INODE_APPEND) {
+ sctx->cur_inode_flip_flags |= (left_flags &
+ BTRFS_INODE_APPEND);
+ left_flags &= ~BTRFS_INODE_APPEND;
+ need_chattr = 1;
+ }
+ if (need_chattr) {
+ need_chattr = 0;
+ ret = send_chattr(sctx, sctx->cur_ino,
+ sctx->cur_inode_gen, left_flags);
+ if (ret < 0)
+ goto out;
+ /*
+ * left_flags is now an accurate rep of what the
+ * receiving inode's flags are
+ */
+ sctx->cur_inode_receive_flags = left_flags;
+ }
+ }
+
if (!at_end && sctx->cmp_key->objectid == sctx->cur_ino)
goto out;
ret = get_inode_info(sctx->send_root, sctx->cur_ino, NULL, NULL,
- &left_mode, &left_uid, &left_gid, NULL);
+ &left_mode, &left_uid, &left_gid, NULL, &left_flags);
if (ret < 0)
goto out;
@@ -5819,12 +5918,14 @@ static int finish_inode_if_needed(struct send_ctx
*sctx, int at_end)
need_chmod = 1;
if (sctx->cur_inode_next_write_offset == sctx->cur_inode_size)
need_truncate = 0;
+ if (left_flags)
+ need_chattr = 1;
} else {
u64 old_size;
ret = get_inode_info(sctx->parent_root, sctx->cur_ino,
&old_size, NULL, &right_mode, &right_uid,
- &right_gid, NULL);
+ &right_gid, NULL, NULL);
if (ret < 0)
goto out;
@@ -5897,6 +5998,27 @@ static int finish_inode_if_needed(struct send_ctx *sctx,
int at_end)
goto out;
}
+ /*
+ * At this point, if we toggled stuff earlier, untoggle it
+ * force a chattr and fix the flags
+ */
+ if (sctx->cur_inode_flip_flags) {
+ left_flags |= sctx->cur_inode_flip_flags;
+ }
+
+ /*
+ * We either need a chattr because this inode is new, or we need to make
+ * a change due to a discrepancy between left_flags and receive_flags
+ */
+ if (need_chattr || (sctx->cur_inode_receive_flags != left_flags)) {
+ ret = send_chattr(sctx, sctx->cur_ino, sctx->cur_inode_gen,
+ left_flags);
+ if (ret < 0)
+ goto out;
+ }
+ sctx->cur_inode_flip_flags = 0;
+ sctx->cur_inode_receive_flags = 0;
+ sctx->receive_flags_valid = 0;
out:
return ret;
}
@@ -6198,12 +6320,12 @@ static int dir_changed(struct send_ctx *sctx, u64 dir)
int ret;
ret = get_inode_info(sctx->send_root, dir, NULL, &new_gen, NULL, NULL,
- NULL, NULL);
+ NULL, NULL, NULL);
if (ret)
return ret;
ret = get_inode_info(sctx->parent_root, dir, NULL, &orig_gen, NULL,
- NULL, NULL, NULL);
+ NULL, NULL, NULL, NULL);
if (ret)
return ret;
diff --git a/fs/btrfs/send.h b/fs/btrfs/send.h
index ead397f7034f..b6e6dcc3db70 100644
--- a/fs/btrfs/send.h
+++ b/fs/btrfs/send.h
@@ -77,6 +77,7 @@ enum btrfs_send_cmd {
BTRFS_SEND_C_END,
BTRFS_SEND_C_UPDATE_EXTENT,
+ BTRFS_SEND_C_CHATTR,
__BTRFS_SEND_C_MAX,
};
#define BTRFS_SEND_C_MAX (__BTRFS_SEND_C_MAX - 1)
@@ -114,6 +115,7 @@ enum {
BTRFS_SEND_A_CLONE_PATH,
BTRFS_SEND_A_CLONE_OFFSET,
BTRFS_SEND_A_CLONE_LEN,
+ BTRFS_SEND_A_CHATTR,
__BTRFS_SEND_A_MAX,
};
--
2.17.0
--
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