xchk_trans_alloc_empty can't return errors, so return the allocated
transaction directly instead of an output double pointer argument.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
xfs_dir_replace trips an assertion if you tell it to change a dirent to
point to an inumber that it already points at. Look up the dotdot entry
directly to confirm that we need to make a change.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Metadata directory trees make reasoning about the parent of a file more
difficult. Traditionally, user files are children of sb_rootino, and
metadata files are "children" of the superblock. Now, we add a third
possibility -- some metadata files can be children of sb_metadirino, but
the classic ones (rt free space data and quotas) are left alone.
Let's add some helper functions (instead of open-coding the logic
everywhere) to make scrub logic easier to understand.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Add a helper to switch between the different directory formats for
removing a directory entry.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
Add a helper to switch between the different directory formats for
removing a directory entry.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
Add a helper to switch between the different directory formats for
creating a directory entry and to handle the XFS_DA_OP_JUSTCHECK flag
based on the passed in ino number field.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
The function are defined in the dir_repair.c file, but not called
elsewhere, so delete the unused function.
fs/xfs/scrub/dir_repair.c:186:1: warning: unused function 'xrep_dir_self_parent'.
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=8867
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
The atomic file exchange-range functionality is now a permanent
filesystem feature instead of a dynamic log-incompat feature. It cannot
be turned on at runtime, so we no longer need the XCHK_FSGATES flags and
whatnot that supported it. Remove the flag and the enable function, and
move the xfs_has_exchange_range checks to the start of the repair
functions.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Add a second callback function to xchk_xattr_walk so that we can do
something in between attr leaf blocks. This will be used by the next
patch to see if we should flush cached parent pointer updates to
constrain memory usage.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
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>
For filesystems with parent pointers, scan the entire filesystem looking
for parent pointers that target the directory we're rebuilding instead
of trying to salvage whatever we can from the directory data blocks.
This will be more robust than salvaging, but there's more code to come.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
This patch modifies xfs_link to add a parent pointer to the inode.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
[djwong: minor rebase fixes]
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The VFS inc_nlink function does not explicitly check for integer
overflows in the i_nlink field. Instead, it checks the link count
against s_max_links in the vfs_{link,create,rename} functions. XFS
sets the maximum link count to 2.1 billion, so integer overflows should
not be a problem.
However. It's possible that online repair could find that a file has
more than four billion links, particularly if the link count got
corrupted while creating hardlinks to the file. The di_nlinkv2 field is
not large enough to store a value larger than 2^32, so we ought to
define a magic pin value of ~0U which means that the inode never gets
deleted. This will prevent a UAF error if the repair finds this
situation and users begin deleting links to the file.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
When we're repairing a directory structure or fixing the dotdot entry of
a subdirectory, it's possible that we won't ever find a parent for the
subdirectory. When this is the case, move it to the orphanage, aka
/lost+found.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
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>
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>
If a directory looks like it's in bad shape, try to sift through the
rubble to find whatever directory entries we can, scan the directory
tree for the parent (if needed), stage the new directory contents in a
temporary file and use the atomic extent swapping mechanism to commit
the results in bulk.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
