- 24 Apr, 2024 4 commits
-
-
Chandan Babu R authored
Merge tag 'scrub-pptrs-6.10_2024-04-23' of https://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfs-linux into xfs-6.10-mergeC xfs: scrubbing for parent pointers Teach online fsck to use parent pointers to assist in checking directories, parent pointers, extended attributes, and link counts. Signed-off-by:
Darrick J. Wong <djwong@kernel.org> Signed-off-by:
Chandan Babu R <chandanbabu@kernel.org> * tag 'scrub-pptrs-6.10_2024-04-23' of https://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfs-linux: xfs: check parent pointer xattrs when scrubbing xfs: walk directory parent pointers to determine backref count xfs: deferred scrub of parent pointers xfs: scrub parent pointers xfs: deferred scrub of dirents xfs: check dirents have parent pointers xfs: revert commit 44af6c7e
-
Chandan Babu R authored
Merge tag 'pptrs-6.10_2024-04-23' of https://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfs-linux into xfs-6.10-mergeC xfs: Parent Pointers This is the latest parent pointer attributes for xfs. The goal of this patch set is to add a parent pointer attribute to each inode. The attribute name containing the parent inode, generation, and directory offset, while the attribute value contains the file name. This feature will enable future optimizations for online scrub, shrink, nfs handles, verity, or any other feature that could make use of quickly deriving an inodes path from the mount point. Directory parent pointers are stored as namespaced extended attributes of a file. Because parent pointers are an indivisible tuple of (dirent_name, parent_ino, parent_gen) we cannot use the usual attr name lookup functions to find a parent pointer. This is solvable by introducing a new lookup mode that checks both the name and the value of the xattr. Therefore, introduce this new name-value lookup mode that's gated on the XFS_ATTR_PARENT namespace. This requires the introduction of new opcodes for the extended attribute update log intent items, which actually means that parent pointers (itself an INCOMPAT feature) does not depend on the LOGGED_XATTRS log incompat feature bit. To reduce collisions on the dirent names of parent pointers, introduce a new attr hash mode that is the dir2 namehash of the dirent name xor'd with the parent inode number. Signed-off-by:
-
Chandan Babu R authored
Merge tag 'improve-attr-validation-6.10_2024-04-23' of https://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfs-linux into xfs-6.10-mergeC xfs: improve extended attribute validation Prior to introducing parent pointer extended attributes, let's spend some time cleaning up the attr code and strengthening the validation that it performs on attrs coming in from the disk. Signed-off-by:
-
Chandan Babu R authored
Merge tag 'shrink-dirattr-args-6.10_2024-04-23' of https://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfs-linux into xfs-6.10-mergeC xfs: shrink struct xfs_da_args Let's clean out some unused flags and fields from struct xfs_da_args. Signed-off-by:
-
- 23 Apr, 2024 36 commits
-
-
Darrick J. Wong authored
Check parent pointer xattrs as part of scrubbing xattrs. Signed-off-by:
Christoph Hellwig <hch@lst.de>
-
Darrick J. Wong authored
If the filesystem has parent pointers enabled, walk the parent pointers of subdirectories to determine the true backref count. In theory each subdir should have a single parent reachable via dotdot, but in the case of (corrupt) subdirs with multiple parents, we need to keep the link counts high enough that the directory loop detector will be able to correct the multiple parents problems. Signed-off-by:
-
Darrick J. Wong authored
If the trylock-based dirent check fails, retain those parent pointers and check them at the end. This may involve dropping the locks on the file being scanned, so yay. Signed-off-by:
-
Darrick J. Wong authored
Actually check parent pointers now. Signed-off-by:
-
Darrick J. Wong authored
If the trylock-based parent pointer check fails, retain those dirents and check them at the end. This may involve dropping the locks on the file being scanned, so yay. Signed-off-by:
-
Darrick J. Wong authored
If the fs has parent pointers, we need to check that each child dirent points to a file that has a parent pointer pointing back at us. Signed-off-by:
-
Darrick J. Wong authored
Add parent pointers to the list of supported features. Signed-off-by:
-
Darrick J. Wong authored
In my haste to fix what I thought was a performance problem in the attr scrub code, I neglected to notice that the xfs_attr_get_ilocked also had the effect of checking that attributes can actually be looked up through the attr dabtree. Fix this. Fixes: 44af6c7e ("xfs: don't load local xattr values during scrub") Signed-off-by:
-
Darrick J. Wong authored
Let's also drop the oversized minimum log computations for reflink and rmap that were the result of bugs introduced many years ago. Signed-off-by:
Allison Henderson <allison.henderson@oracle.com> Reviewed-by:
-
Darrick J. Wong authored
Dave and I were discussing some recent test regressions as a result of me turning on nrext64=1 on realtime filesystems, when we noticed that the minimum log size of a 32M filesystem jumped from 954 blocks to 4287 blocks. Digging through xfs_log_calc_max_attrsetm_res, Dave noticed that @size contains the maximum estimated amount of space needed for a local format xattr, in bytes, but we feed this quantity to XFS_NEXTENTADD_SPACE_RES, which requires units of blocks. This has resulted in an overestimation of the minimum log size over the years. We should nominally correct this, but there's a backwards compatibility problem -- if we enable it now, the minimum log size will decrease. If a corrected mkfs formats a filesystem with this new smaller log size, a user will encounter mount failures on an uncorrected kernel due to the larger minimum log size computations there. Therefore, turn this on for parent pointers because it wasn't merged at all upstream when this issue was discovered. Signed-off-by:
-
Allison Henderson authored
Create an incompat feature bit and a fs geometry flag so that we can enable the feature in the ondisk superblock and advertise its existence to userspace. Signed-off-by:
Mark Tinguely <mark.tinguely@oracle.com> Signed-off-by:
Dave Chinner <dchinner@redhat.com> Signed-off-by:
Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by:
-
Allison Henderson authored
When an inode is removed, it may also cause the attribute fork to be removed if it is the last attribute. This transaction gets flushed to the log, but if the system goes down before we could inactivate the symlink, the log recovery tries to inactivate this inode (since it is on the unlinked list) but the verifier trips over the remote value and leaks it. Hence we ended up with a file in this odd state on a "clean" mount. The "obvious" fix is to prohibit erasure of the attr fork to avoid tripping over the verifiers when pptrs are enabled. Signed-off-by:
-
Darrick J. Wong authored
This patch adds a pair of new file ioctls to retrieve the parent pointer of a given inode. They both return the same results, but one operates on the file descriptor passed to ioctl() whereas the other allows the caller to specify a file handle for which the caller wants results. Signed-off-by:
-
Darrick J. Wong authored
Split out the functions that generate file/fs handles and map them back into dentries in preparation for the GETPARENTS ioctl next. Signed-off-by:
-
Darrick J. Wong authored
Move the handle managemnet code (and the attrmulti code that uses it) to xfs_handle.c. Signed-off-by:
-
Allison Henderson authored
Pass the attr value to put_listent when we have local xattrs or shortform xattrs. This will enable the GETPARENTS ioctl to use xfs_attr_list as its backend. Signed-off-by:
-
Allison Henderson authored
Parent pointers are internal filesystem metadata. They're not intended to be directly visible to userspace, so filter them out of xfs_xattr_put_listent so that they don't appear in listxattr. Signed-off-by:
Andrey Albershteyn <aalbersh@redhat.com> Reviewed-by:
-
Allison Henderson authored
Cross renames are handled separately from standard renames, and need different handling to update the parent attributes correctly. Signed-off-by:
-
Allison Henderson authored
This patch removes the old parent pointer attribute during the rename operation, and re-adds the updated parent pointer. Signed-off-by:
-
Allison Henderson authored
This patch removes the parent pointer attribute during unlink Signed-off-by:
-
Allison Henderson authored
This patch modifies xfs_symlink to add a parent pointer to the inode. Signed-off-by:
-
Allison Henderson authored
This patch modifies xfs_link to add a parent pointer to the inode. Signed-off-by:
-
Allison Henderson authored
Add parent pointer attribute during xfs_create, and subroutines to initialize attributes. Note that the xfs_attr_intent object contains a pointer to the caller's xfs_da_args object, so the latter must persist until transaction commit. Signed-off-by:
-
Darrick J. Wong authored
Although directory entry and parent pointer recordsets look very similar (name -> ino), there's one major difference between them: a file can be hardlinked from multiple parent directories with the same filename. This is common in shared container environments where a base directory tree might be hardlink-copied multiple times. IOWs the same 'ls' program might be hardlinked to multiple /srv/*/bin/ls paths. We don't want parent pointer operations to bog down on hash collisions between the same dirent name, so create a special hash function that mixes in the parent directory inode number. Signed-off-by:
-
Allison Henderson authored
We need to add, remove or modify parent pointer attributes during create/link/unlink/rename operations atomically with the dirents in the parent directories being modified. This means they need to be modified in the same transaction as the parent directories, and so we need to add the required space for the attribute modifications to the transaction reservations. Signed-off-by:
-
Allison Henderson authored
The attr name of a parent pointer is a string, and the attr value of a parent pointer is (more or less) a file handle. So we need to modify attr_namecheck to verify the parent pointer name, and add a xfs_parent_valuecheck function to sanitize the handle. At the same time, we need to validate attr values during log recovery if the xattr is really a parent pointer. Signed-off-by:
-
Allison Henderson authored
Tmp files are used as part of rename operations and will need attr forks initialized for parent pointers. Expose the init_xattrs parameter to the calling function to initialize the fork. Signed-off-by:
-
Darrick J. Wong authored
For parent pointer updates, record the i_generation of the file that is being updated so that we don't accidentally jump generations. Signed-off-by:
-
Darrick J. Wong authored
Make the necessary alterations to the extended attribute log intent item ondisk format so that we can log parent pointer operations. This requires the creation of new opcodes specific to parent pointers, and a new four-argument replace operation to handle renames. At this point this part of the patchset has changed so much from what Allison original wrote that I no longer think her SoB applies. Signed-off-by:
-
Darrick J. Wong authored
Move this feature check down to the per-op checks so that we can ensure that we never see parent pointer attr items on non-pptr filesystems, and that logged xattrs are turned on for non-pptr attr items. Signed-off-by:
-
Darrick J. Wong authored
If a file is hardlinked with the same name but from multiple parents, the parent pointers will all have the same dirent name (== attr name) but with different parent_ino/parent_gen values. To disambiguate, we need to be able to match on both the attr name and the attr value. This is in contrast to regular xattrs, which are matchtg edit d only on name. Therefore, plumb in the ability to match shortform and local attrs on name and value in the XFS_ATTR_PARENT namespace. Parent pointer attr values are never large enough to be stored in a remote attr, so we need can reject these cases as corruption. Signed-off-by:
-
Allison Henderson authored
We need to define the parent pointer attribute format before we start adding support for it into all the code that needs to use it. The EA format we will use encodes the following information: name={dirent name} value={parent inumber, parent inode generation} hash=xfs_dir2_hashname(dirent name) ^ (parent_inumber) The inode/gen gives all the information we need to reliably identify the parent without requiring child->parent lock ordering, and allows userspace to do pathname component level reconstruction without the kernel ever needing to verify the parent itself as part of ioctl calls. By using the name-value lookup mode in the extended attribute code to match parent pointers using both the xattr name and value, we can identify the exact parent pointer EA we need to modify/remove in rename/unlink operations without searching the entire EA space. By storing the dirent name, we have enough information to be able to validate and reconstruct damaged directory trees. Earlier iterations of this patchset encoded the directory offset in the parent pointer key, but this format required repair to keep that in sync across directory rebuilds, which is unnecessary complexity. Signed-off-by: -
Allison Henderson authored
Add the new parent attribute type. XFS_ATTR_PARENT is used only for parent pointer entries; it uses reserved blocks like XFS_ATTR_ROOT. Signed-off-by:
-
Darrick J. Wong authored
Create a separate function to compute name hashvalues for extended attributes. When we get to parent pointers we'll be altering the rules so that metadump obfuscation doesn't turn heinous. Signed-off-by:
-
Darrick J. Wong authored
Move the code that adds the incore xfs_attr_item deferred work data to a transaction live with the ATTRI log item code. This means that the upper level extended attribute code no longer has to know about the inner workings of the ATTRI log items. Signed-off-by:
-
Christoph Hellwig authored
Checking the flags match is much cheaper than a memcmp, so do it early on in xfs_attr_match, and also add a little helper to calculate the match mask right under the comment explaining the logic for it. Signed-off-by:
-
