From 8996a48c0a8ed01c55f52e6794625c95a9977ee6 Mon Sep 17 00:00:00 2001 From: Filipe Manana Date: Thu, 12 Mar 2015 15:16:20 +0000 Subject: [PATCH] Btrfs: incremental send, clear name from cache after orphanization If a directory's reference ends up being orphanized, because the inode currently being processed has a new path that matches that directory's path, make sure we evict the name of the directory from the name cache. This is because there might be descendent inodes (either directories or regular files) that will be orphanized later too, and therefore the orphan name of the ancestor must be used, otherwise we send issue rename operations with a wrong path in the send stream. Reproducer: $ mkfs.btrfs -f /dev/sdb $ mount /dev/sdb /mnt $ mkdir -p /mnt/data/n1/n2/p1/p2 $ mkdir /mnt/data/n4 $ mkdir -p /mnt/data/p1/p2 $ btrfs subvolume snapshot -r /mnt /mnt/snap1 $ mv /mnt/data/p1/p2 /mnt/data $ mv /mnt/data/n1/n2/p1/p2 /mnt/data/p1 $ mv /mnt/data/p2 /mnt/data/n1/n2/p1 $ mv /mnt/data/n1/n2 /mnt/data/p1 $ mv /mnt/data/p1 /mnt/data/n4 $ mv /mnt/data/n4/p1/n2/p1 /mnt/data $ btrfs subvolume snapshot -r /mnt /mnt/snap2 $ btrfs send /mnt/snap1 -f /tmp/1.send $ btrfs send -p /mnt/snap1 /mnt/snap2 -f /tmp/2.send $ mkfs.btrfs -f /dev/sdc $ mount /dev/sdc /mnt2 $ btrfs receive /mnt2 -f /tmp/1.send $ btrfs receive /mnt2 -f /tmp/2.send ERROR: rename data/p1/p2 -> data/n4/p1/p2 failed. no such file or directory Directories data/p1 (inode 263) and data/p1/p2 (inode 264) in the parent snapshot are both orphanized during the incremental send, and as soon as data/p1 is orphanized, we must make sure that when orphanizing data/p1/p2 we use a source path of o263-6-o/p2 for the rename operation instead of the old path data/p1/p2 (the one before the orphanization of inode 263). A test case for xfstests follows soon. Reported-by: Robbie Ko Signed-off-by: Filipe Manana Signed-off-by: Chris Mason --- fs/btrfs/send.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c index 571de5a08fe7..00cb924884f5 100644 --- a/fs/btrfs/send.c +++ b/fs/btrfs/send.c @@ -3610,10 +3610,27 @@ verbose_printk("btrfs: process_recorded_refs %llu\n", sctx->cur_ino); if (ret < 0) goto out; if (ret) { + struct name_cache_entry *nce; + ret = orphanize_inode(sctx, ow_inode, ow_gen, cur->full_path); if (ret < 0) goto out; + /* + * Make sure we clear our orphanized inode's + * name from the name cache. This is because the + * inode ow_inode might be an ancestor of some + * other inode that will be orphanized as well + * later and has an inode number greater than + * sctx->send_progress. We need to prevent + * future name lookups from using the old name + * and get instead the orphan name. + */ + nce = name_cache_search(sctx, ow_inode, ow_gen); + if (nce) { + name_cache_delete(sctx, nce); + kfree(nce); + } } else { ret = send_unlink(sctx, cur->full_path); if (ret < 0) -- GitLab