summaryrefslogtreecommitdiff
path: root/fs/xfs/scrub/findparent.h
AgeCommit message (Collapse)AuthorFilesLines
2024-04-24xfs: implement live updates for directory repairsDarrick J. Wong1-2/+8
While we're scanning the filesystem for parent pointers that we can turn into dirents, we cannot hold the IOLOCK or ILOCK of the directory being repaired. Therefore, we need to set up a dirent hook so that we can keep the temporary directory up to date with the rest of the filesystem. Hence we add the ability to *remove* entries from the temporary dir. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2024-04-16xfs: ask the dentry cache if it knows the parent of a directoryDarrick J. Wong1-0/+1
It's possible that the dentry cache can tell us the parent of a directory. Therefore, when repairing directory dot dot entries, query the dcache as a last resort before scanning the entire filesystem. A reviewer asks: "How high is the chance that we actually have a valid dcache entry for a file in a corrupted directory?" There's a decent chance of this actually working. Say you have a 1000-block directory foo, and block 980 gets corrupted. Let's further suppose that block 0 has a correct entry for ".." and "bar". If someone accesses /mnt/foo/bar, that will cause the dcache to create a dentry from /mnt to /mnt/foo whose d_parent points back to /mnt. If you then want to rebuild the directory, XFS can obtain the parent from the dcache without needing to wander into parent pointers or scan the filesystem to find /mnt's connection to foo. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2024-04-16xfs: scan the filesystem to repair a directory dotdot entryDarrick J. Wong1-0/+49
Teach the online directory repair code to scan the filesystem so that we can set the dotdot entry when we're rebuilding a directory. This involves dropping ILOCK on the directory that we're repairing, which means that the VFS can sneak in and tell us to update dotdot at any time. Deal with these races by using a dirent hook to absorb dotdot updates, and be careful not to check the scan results until after we've retaken the ILOCK. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>