Filipe David Borba Manana
2014-Feb-16 13:43 UTC
[PATCH] Btrfs: incremental send, fix invalid path after dir rename
This fixes yet one more case not caught by the commit titled: Btrfs: fix infinite path build loops in incremental send In this case, even before the initial full send, we have a directory which is a child of a directory with a higher inode number. Then we perform the initial send, and after we rename both the child and the parent, without moving them around. After doing these 2 renames, an incremental send sent a rename instruction for the child directory which contained an invalid "from" path (referenced the parent's old name, not the new one), which made the btrfs receive command fail. Steps to reproduce: $ mkfs.btrfs -f /dev/sdb3 $ mount /dev/sdb3 /mnt/btrfs $ mkdir -p /mnt/btrfs/a/b $ mkdir /mnt/btrfs/d $ mkdir /mnt/btrfs/a/b/c $ mv /mnt/btrfs/d /mnt/btrfs/a/b/c $ btrfs subvolume snapshot -r /mnt/btrfs /mnt/btrfs/snap1 $ btrfs send /mnt/btrfs/snap1 -f /tmp/base.send $ mv /mnt/btrfs/a/b/c /mnt/btrfs/a/b/x $ mv /mnt/btrfs/a/b/x/d /mnt/btrfs/a/b/x/y $ btrfs subvolume snapshot -r /mnt/btrfs /mnt/btrfs/snap2 $ btrfs send -p /mnt/btrfs/snap1 /mnt/btrfs/snap2 -f /tmp/incremental.send $ umout /mnt/btrfs $ mkfs.btrfs -f /dev/sdb3 $ mount /dev/sdb3 /mnt/btrfs $ btrfs receive /mnt/btrfs -f /tmp/base.send $ btrfs receive /mnt/btrfs -f /tmp/incremental.send The second btrfs receive command failed with: "ERROR: rename a/b/c/d -> a/b/x/y failed. No such file or directory" A test case for xfstests follows. Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com> --- fs/btrfs/send.c | 41 ++++++++++++++++++++++++++++++++++------- 1 file changed, 34 insertions(+), 7 deletions(-) diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c index b6d416c..7dbed58 100644 --- a/fs/btrfs/send.c +++ b/fs/btrfs/send.c @@ -2847,19 +2847,48 @@ static int apply_dir_move(struct send_ctx *sctx, struct pending_dir_move *pm) { struct fs_path *from_path = NULL; struct fs_path *to_path = NULL; + struct fs_path *name = NULL; u64 orig_progress = sctx->send_progress; struct recorded_ref *cur; + u64 parent_ino, parent_gen; int ret; + name = fs_path_alloc(); from_path = fs_path_alloc(); - if (!from_path) - return -ENOMEM; + if (!name || !from_path) { + ret = -ENOMEM; + goto out; + } - sctx->send_progress = pm->ino; - ret = get_cur_path(sctx, pm->ino, pm->gen, from_path); + ret = del_waiting_dir_move(sctx, pm->ino); + ASSERT(ret == 0); + + ret = get_first_ref(sctx->parent_root, pm->ino, + &parent_ino, &parent_gen, name); if (ret < 0) goto out; + if (parent_ino == sctx->cur_ino) { + /* child only renamed, not moved */ + ASSERT(parent_gen == sctx->cur_inode_gen); + ret = get_cur_path(sctx, sctx->cur_ino, sctx->cur_inode_gen, + from_path); + if (ret < 0) + goto out; + ret = fs_path_add_path(from_path, name); + if (ret < 0) + goto out; + } else { + /* child moved and maybe renamed too */ + sctx->send_progress = pm->ino; + ret = get_cur_path(sctx, pm->ino, pm->gen, from_path); + if (ret < 0) + goto out; + } + + fs_path_free(name); + name = NULL; + to_path = fs_path_alloc(); if (!to_path) { ret = -ENOMEM; @@ -2867,9 +2896,6 @@ static int apply_dir_move(struct send_ctx *sctx, struct pending_dir_move *pm) } sctx->send_progress = sctx->cur_ino + 1; - ret = del_waiting_dir_move(sctx, pm->ino); - ASSERT(ret == 0); - ret = get_cur_path(sctx, pm->ino, pm->gen, to_path); if (ret < 0) goto out; @@ -2893,6 +2919,7 @@ static int apply_dir_move(struct send_ctx *sctx, struct pending_dir_move *pm) } out: + fs_path_free(name); fs_path_free(from_path); fs_path_free(to_path); sctx->send_progress = orig_progress; -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html