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path: root/fs/xfs/xfs_inode.h
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2024-05-02xfs: widen flags argument to the xfs_iflags_* helpersDarrick J. Wong
xfs_inode.i_flags is an unsigned long, so make these helpers take that as the flags argument instead of unsigned short. This is needed for the next patch. While we're at it, remove the iflags variable from xfs_iget_cache_miss because we no longer need it. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Andrey Albershteyn <aalbersh@redhat.com>
2024-04-23xfs: fix corruptions in the directory treeDarrick J. Wong
Repair corruptions in the directory tree itself. Cycles are broken by removing an incoming parent->child link. Multiply-owned directories are fixed by pruning the extra parent -> child links Disconnected subtrees are reconnected to the lost and found. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2024-04-23xfs: Expose init_xattrs in xfs_create_tmpfileAllison Henderson
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: Allison Henderson <allison.henderson@oracle.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2024-04-15xfs: Increase XFS_DEFER_OPS_NR_INODES to 5Allison Henderson
Renames that generate parent pointer updates can join up to 5 inodes locked in sorted order. So we need to increase the number of defer ops inodes and relock them in the same way. Signed-off-by: Allison Henderson <allison.henderson@oracle.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Catherine Hoang <catherine.hoang@oracle.com> [djwong: have one sorting function] Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2024-04-15xfs: check AGI unlinked inode bucketsDarrick J. Wong
Look for corruptions in the AGI unlinked bucket chains. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2024-04-15xfs: move orphan files to the orphanageDarrick J. Wong
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>
2024-04-15xfs: ensure unlinked list state is consistent with nlink during scrubDarrick J. Wong
Now that we have the means to tell if an inode is on an unlinked inode list or not, we can check that an inode with zero link count is on the unlinked list; and an inode that has nonzero link count is not on that list. Make repair clean things up too. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2024-04-15xfs: create temporary files and directories for online repairDarrick J. Wong
Teach the online repair code how to create temporary files or directories. These temporary files can be used to stage reconstructed information until we're ready to perform an atomic extent swap to commit the new metadata. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2024-04-15xfs: hoist multi-fsb allocation unit detection to a helperDarrick J. Wong
Replace the open-coded logic to decide if a file has a multi-fsb allocation unit to a helper to make the code easier to read. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2024-04-15xfs: create a new helper to return a file's allocation unitDarrick J. Wong
Create a new helper function to calculate the fundamental allocation unit (i.e. the smallest unit of space we can allocate) of a file. Things are going to get hairy with range-exchange on the realtime device, so prepare for this now. Remove the static attribute from xfs_is_falloc_aligned since the next patch will need it. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2024-04-15xfs: move xfs_iops.c declarations out of xfs_inode.hDarrick J. Wong
Similarly, move declarations of public symbols of xfs_iops.c from xfs_inode.h to xfs_iops.h. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2024-04-15xfs: move inode lease breaking functions to xfs_inode.cDarrick J. Wong
The lease breaking functions operate at the scope of the entire VFS inode, not subranges of a file. Move them to xfs_inode.c since they're already declared in xfs_inode.h. This cleanup moves us closer to having xfs_FOO.h declare only the symbols in xfs_FOO.c. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2024-02-22xfs: track directory entry updates during live nlinks fsckDarrick J. Wong
Create the necessary hooks in the directory operations (create/link/unlink/rename) code so that our live nlink scrub code can stay up to date with link count updates in the rest of the filesystem. This will be the means to keep our shadow link count information up to date while the scan runs in real time. In online fsck part 2, we'll use these same hooks to handle repairs to directories and parent pointer information. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2024-02-22xfs: create a helper to count per-device inode block usageDarrick J. Wong
Create a helper to compute the number of blocks that a file has allocated from the data realtime volumes. This patch was split out to reduce the size of the upcoming quotacheck patch. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2024-02-19xfs: Remove mrlock wrapperMatthew Wilcox (Oracle)
mrlock was an rwsem wrapper that also recorded whether the lock was held for read or write. Now that we can ask the generic code whether the lock is held for read or write, we can remove this wrapper and use an rwsem directly. As the comment says, we can't use lockdep to assert that the ILOCK is held for write, because we might be in a workqueue, and we aren't able to tell lockdep that we do in fact own the lock. Reviewed-by: "Darrick J. Wong" <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org> Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
2024-02-19xfs: Replace xfs_isilocked with xfs_assert_ilockedMatthew Wilcox (Oracle)
To use the new rwsem_assert_held()/rwsem_assert_held_write(), we can't use the existing ASSERT macro. Add a new xfs_assert_ilocked() and convert all the callers. Fix an apparent bug in xfs_isilocked(): If the caller specifies XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL, xfs_assert_ilocked() will check both the IOLOCK and the ILOCK are held for write. xfs_isilocked() only checked that the ILOCK was held for write. xfs_assert_ilocked() is always on, even if DEBUG or XFS_WARN aren't defined. It's a cheap check, so I don't think it's worth defining it away. Reviewed-by: "Darrick J. Wong" <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org> Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
2023-12-15xfs: set inode sick state flags when we zap either ondisk forkDarrick J. Wong
In a few patches, we'll add some online repair code that tries to massage the ondisk inode record just enough to get it to pass the inode verifiers so that we can continue with more file repairs. Part of that massaging can include zapping the ondisk forks to clear errors. After that point, the bmap fork repair functions will rebuild the zapped forks. Christoph asked for stronger protections against online repair zapping a fork to get the inode to load vs. other threads trying to access the partially repaired file. Do this by adding a special "[DA]FORK_ZAPPED" inode health flag whenever repair zaps a fork, and sprinkling checks for that flag into the various file operations for things that don't like handling an unexpected zero-extents fork. In practice xfs_scrub will scrub and fix the forks almost immediately after zapping them, so the window is very small. However, if a crash or unmount should occur, we can still detect these zapped inode forks by looking for a zero-extents fork when data was expected. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-11-20xfs: respect the stable writes flag on the RT deviceChristoph Hellwig
Update the per-folio stable writes flag dependening on which device an inode resides on. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20231025141020.192413-5-hch@lst.de Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-10-23xfs: allow read IO and FICLONE to run concurrentlyCatherine Hoang
One of our VM cluster management products needs to snapshot KVM image files so that they can be restored in case of failure. Snapshotting is done by redirecting VM disk writes to a sidecar file and using reflink on the disk image, specifically the FICLONE ioctl as used by "cp --reflink". Reflink locks the source and destination files while it operates, which means that reads from the main vm disk image are blocked, causing the vm to stall. When an image file is heavily fragmented, the copy process could take several minutes. Some of the vm image files have 50-100 million extent records, and duplicating that much metadata locks the file for 30 minutes or more. Having activities suspended for such a long time in a cluster node could result in node eviction. Clone operations and read IO do not change any data in the source file, so they should be able to run concurrently. Demote the exclusive locks taken by FICLONE to shared locks to allow reads while cloning. While a clone is in progress, writes will take the IOLOCK_EXCL, so they block until the clone completes. Link: https://lore.kernel.org/linux-xfs/8911B94D-DD29-4D6E-B5BC-32EAF1866245@oracle.com/ Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com> Reviewed-by: "Darrick J. Wong" <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
2023-09-12xfs: make inode unlinked bucket recovery work with quotacheckDarrick J. Wong
Teach quotacheck to reload the unlinked inode lists when walking the inode table. This requires extra state handling, since it's possible that a reloaded inode will get inactivated before quotacheck tries to scan it; in this case, we need to ensure that the reloaded inode does not have dquots attached when it is freed. Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2023-09-12xfs: reload entire unlinked bucket listsDarrick J. Wong
The previous patch to reload unrecovered unlinked inodes when adding a newly created inode to the unlinked list is missing a key piece of functionality. It doesn't handle the case that someone calls xfs_iget on an inode that is not the last item in the incore list. For example, if at mount time the ondisk iunlink bucket looks like this: AGI -> 7 -> 22 -> 3 -> NULL None of these three inodes are cached in memory. Now let's say that someone tries to open inode 3 by handle. We need to walk the list to make sure that inodes 7 and 22 get loaded cold, and that the i_prev_unlinked of inode 3 gets set to 22. Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2023-09-12xfs: use i_prev_unlinked to distinguish inodes that are not on the unlinked listDarrick J. Wong
Alter the definition of i_prev_unlinked slightly to make it more obvious when an inode with 0 link count is not part of the iunlink bucket lists rooted in the AGI. This distinction is necessary because it is not sufficient to check inode.i_nlink to decide if an inode is on the unlinked list. Updates to i_nlink can happen while holding only ILOCK_EXCL, but updates to an inode's position in the AGI unlinked list (which happen after the nlink update) requires both ILOCK_EXCL and the AGI buffer lock. The next few patches will make it possible to reload an entire unlinked bucket list when we're walking the inode table or performing handle operations and need more than the ability to iget the last inode in the chain. The upcoming directory repair code also needs to be able to make this distinction to decide if a zero link count directory should be moved to the orphanage or allowed to inactivate. An upcoming enhancement to the online AGI fsck code will need this distinction to check and rebuild the AGI unlinked buckets. Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2023-06-05xfs: collect errors from inodegc for unlinked inode recoveryDave Chinner
Unlinked list recovery requires errors removing the inode the from the unlinked list get fed back to the main recovery loop. Now that we offload the unlinking to the inodegc work, we don't get errors being fed back when we trip over a corruption that prevents the inode from being removed from the unlinked list. This means we never clear the corrupt unlinked list bucket, resulting in runtime operations eventually tripping over it and shutting down. Fix this by collecting inodegc worker errors and feed them back to the flush caller. This is largely best effort - the only context that really cares is log recovery, and it only flushes a single inode at a time so we don't need complex synchronised handling. Essentially the inodegc workers will capture the first error that occurs and the next flush will gather them and clear them. The flush itself will only report the first gathered error. In the cases where callers can return errors, propagate the collected inodegc flush error up the error handling chain. In the case of inode unlinked list recovery, there are several superfluous calls to flush queued unlinked inodes - xlog_recover_iunlink_bucket() guarantees that it has flushed the inodegc and collected errors before it returns. Hence nothing in the calling path needs to run a flush, even when an error is returned. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Dave Chinner <david@fromorbit.com>
2023-01-19fs: port inode_init_owner() to mnt_idmapChristian Brauner
Convert to struct mnt_idmap. Last cycle we merged the necessary infrastructure in 256c8aed2b42 ("fs: introduce dedicated idmap type for mounts"). This is just the conversion to struct mnt_idmap. Currently we still pass around the plain namespace that was attached to a mount. This is in general pretty convenient but it makes it easy to conflate namespaces that are relevant on the filesystem with namespaces that are relevent on the mount level. Especially for non-vfs developers without detailed knowledge in this area this can be a potential source for bugs. Once the conversion to struct mnt_idmap is done all helpers down to the really low-level helpers will take a struct mnt_idmap argument instead of two namespace arguments. This way it becomes impossible to conflate the two eliminating the possibility of any bugs. All of the vfs and all filesystems only operate on struct mnt_idmap. Acked-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2022-08-05Merge tag 'mm-stable-2022-08-03' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: "Most of the MM queue. A few things are still pending. Liam's maple tree rework didn't make it. This has resulted in a few other minor patch series being held over for next time. Multi-gen LRU still isn't merged as we were waiting for mapletree to stabilize. The current plan is to merge MGLRU into -mm soon and to later reintroduce mapletree, with a view to hopefully getting both into 6.1-rc1. Summary: - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe Lin, Yang Shi, Anshuman Khandual and Mike Rapoport - Some kmemleak fixes from Patrick Wang and Waiman Long - DAMON updates from SeongJae Park - memcg debug/visibility work from Roman Gushchin - vmalloc speedup from Uladzislau Rezki - more folio conversion work from Matthew Wilcox - enhancements for coherent device memory mapping from Alex Sierra - addition of shared pages tracking and CoW support for fsdax, from Shiyang Ruan - hugetlb optimizations from Mike Kravetz - Mel Gorman has contributed some pagealloc changes to improve latency and realtime behaviour. - mprotect soft-dirty checking has been improved by Peter Xu - Many other singleton patches all over the place" [ XFS merge from hell as per Darrick Wong in https://lore.kernel.org/all/YshKnxb4VwXycPO8@magnolia/ ] * tag 'mm-stable-2022-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (282 commits) tools/testing/selftests/vm/hmm-tests.c: fix build mm: Kconfig: fix typo mm: memory-failure: convert to pr_fmt() mm: use is_zone_movable_page() helper hugetlbfs: fix inaccurate comment in hugetlbfs_statfs() hugetlbfs: cleanup some comments in inode.c hugetlbfs: remove unneeded header file hugetlbfs: remove unneeded hugetlbfs_ops forward declaration hugetlbfs: use helper macro SZ_1{K,M} mm: cleanup is_highmem() mm/hmm: add a test for cross device private faults selftests: add soft-dirty into run_vmtests.sh selftests: soft-dirty: add test for mprotect mm/mprotect: fix soft-dirty check in can_change_pte_writable() mm: memcontrol: fix potential oom_lock recursion deadlock mm/gup.c: fix formatting in check_and_migrate_movable_page() xfs: fail dax mount if reflink is enabled on a partition mm/memcontrol.c: remove the redundant updating of stats_flush_threshold userfaultfd: don't fail on unrecognized features hugetlb_cgroup: fix wrong hugetlb cgroup numa stat ...
2022-07-17xfs: add dax dedupe supportShiyang Ruan
Introduce xfs_mmaplock_two_inodes_and_break_dax_layout() for dax files who are going to be deduped. After that, call compare range function only when files are both DAX or not. Link: https://lkml.kernel.org/r/20220603053738.1218681-15-ruansy.fnst@fujitsu.com Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Dan Williams <dan.j.wiliams@intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Goldwyn Rodrigues <rgoldwyn@suse.com> Cc: Goldwyn Rodrigues <rgoldwyn@suse.de> Cc: Jane Chu <jane.chu@oracle.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Naoya Horiguchi <naoya.horiguchi@nec.com> Cc: Ritesh Harjani <riteshh@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-07-14Merge tag 'make-attr-fork-permanent-5.20_2022-07-14' of ↵Darrick J. Wong
git://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfs-linux into xfs-5.20-mergeB xfs: make attr forks permanent This series fixes a use-after-free bug that syzbot uncovered. The UAF itself is a result of a race condition between getxattr and removexattr because callers to getxattr do not necessarily take any sort of locks before calling into the filesystem. Although the race condition itself can be fixed through clever use of a memory barrier, further consideration of the use cases of extended attributes shows that most files always have at least one attribute, so we might as well make them permanent. v2: Minor tweaks suggested by Dave, and convert some more macros to helper functions. Signed-off-by: Darrick J. Wong <djwong@kernel.org> * tag 'make-attr-fork-permanent-5.20_2022-07-14' of git://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfs-linux: xfs: replace inode fork size macros with functions xfs: replace XFS_IFORK_Q with a proper predicate function xfs: use XFS_IFORK_Q to determine the presence of an xattr fork xfs: make inode attribute forks a permanent part of struct xfs_inode xfs: convert XFS_IFORK_PTR to a static inline helper
2022-07-14xfs: double link the unlinked inode listDave Chinner
Now we have forwards traversal via the incore inode in place, we now need to add back pointers to the incore inode to entirely replace the back reference cache. We use the same lookup semantics and constraints as for the forwards pointer lookups during unlinks, and so we can look up any inode in the unlinked list directly and update the list pointers, forwards or backwards, at any time. The only wrinkle in converting the unlinked list manipulations to use in-core previous pointers is that log recovery doesn't have the incore inode state built up so it can't just read in an inode and release it to finish off the unlink. Hence we need to modify the traversal in recovery to read one inode ahead before we release the inode at the head of the list. This populates the next->prev relationship sufficient to be able to replay the unlinked list and hence greatly simplify the runtime code. This recovery algorithm also requires that we actually remove inodes from the unlinked list one at a time as background inode inactivation will result in unlinked list removal racing with the building of the in-memory unlinked list state. We could serialise this by holding the AGI buffer lock when constructing the in memory state, but all that does is lockstep background processing with list building. It is much simpler to flush the inodegc immediately after releasing the inode so that it is unlinked immediately and there is no races present at all. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2022-07-14xfs: track the iunlink list pointer in the xfs_inodeDave Chinner
Having direct access to the i_next_unlinked pointer in unlinked inodes greatly simplifies the processing of inodes on the unlinked list. We no longer need to look up the inode buffer just to find next inode in the list if the xfs_inode is in memory. These improvements will be realised over upcoming patches as other dependencies on the inode buffer for unlinked list processing are removed. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2022-07-12xfs: replace inode fork size macros with functionsDarrick J. Wong
Replace the shouty macros here with typechecked helper functions. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-07-12xfs: replace XFS_IFORK_Q with a proper predicate functionDarrick J. Wong
Replace this shouty macro with a real C function that has a more descriptive name. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-07-09xfs: use XFS_IFORK_Q to determine the presence of an xattr forkDarrick J. Wong
Modify xfs_ifork_ptr to return a NULL pointer if the caller asks for the attribute fork but i_forkoff is zero. This eliminates the ambiguity between i_forkoff and i_af.if_present, which should make it easier to understand the lifetime of attr forks. While we're at it, remove the if_present checks around calls to xfs_idestroy_fork and xfs_ifork_zap_attr since they can both handle attr forks that have already been torn down. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-07-09xfs: make inode attribute forks a permanent part of struct xfs_inodeDarrick J. Wong
Syzkaller reported a UAF bug a while back: ================================================================== BUG: KASAN: use-after-free in xfs_ilock_attr_map_shared+0xe3/0xf6 fs/xfs/xfs_inode.c:127 Read of size 4 at addr ffff88802cec919c by task syz-executor262/2958 CPU: 2 PID: 2958 Comm: syz-executor262 Not tainted 5.15.0-0.30.3-20220406_1406 #3 Hardware name: Red Hat KVM, BIOS 1.13.0-2.module+el8.3.0+7860+a7792d29 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x82/0xa9 lib/dump_stack.c:106 print_address_description.constprop.9+0x21/0x2d5 mm/kasan/report.c:256 __kasan_report mm/kasan/report.c:442 [inline] kasan_report.cold.14+0x7f/0x11b mm/kasan/report.c:459 xfs_ilock_attr_map_shared+0xe3/0xf6 fs/xfs/xfs_inode.c:127 xfs_attr_get+0x378/0x4c2 fs/xfs/libxfs/xfs_attr.c:159 xfs_xattr_get+0xe3/0x150 fs/xfs/xfs_xattr.c:36 __vfs_getxattr+0xdf/0x13d fs/xattr.c:399 cap_inode_need_killpriv+0x41/0x5d security/commoncap.c:300 security_inode_need_killpriv+0x4c/0x97 security/security.c:1408 dentry_needs_remove_privs.part.28+0x21/0x63 fs/inode.c:1912 dentry_needs_remove_privs+0x80/0x9e fs/inode.c:1908 do_truncate+0xc3/0x1e0 fs/open.c:56 handle_truncate fs/namei.c:3084 [inline] do_open fs/namei.c:3432 [inline] path_openat+0x30ab/0x396d fs/namei.c:3561 do_filp_open+0x1c4/0x290 fs/namei.c:3588 do_sys_openat2+0x60d/0x98c fs/open.c:1212 do_sys_open+0xcf/0x13c fs/open.c:1228 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3a/0x7e arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0x0 RIP: 0033:0x7f7ef4bb753d Code: 00 c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 1b 79 2c 00 f7 d8 64 89 01 48 RSP: 002b:00007f7ef52c2ed8 EFLAGS: 00000246 ORIG_RAX: 0000000000000055 RAX: ffffffffffffffda RBX: 0000000000404148 RCX: 00007f7ef4bb753d RDX: 00007f7ef4bb753d RSI: 0000000000000000 RDI: 0000000020004fc0 RBP: 0000000000404140 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0030656c69662f2e R13: 00007ffd794db37f R14: 00007ffd794db470 R15: 00007f7ef52c2fc0 </TASK> Allocated by task 2953: kasan_save_stack+0x19/0x38 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] __kasan_slab_alloc+0x68/0x7c mm/kasan/common.c:467 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook mm/slab.h:519 [inline] slab_alloc_node mm/slub.c:3213 [inline] slab_alloc mm/slub.c:3221 [inline] kmem_cache_alloc+0x11b/0x3eb mm/slub.c:3226 kmem_cache_zalloc include/linux/slab.h:711 [inline] xfs_ifork_alloc+0x25/0xa2 fs/xfs/libxfs/xfs_inode_fork.c:287 xfs_bmap_add_attrfork+0x3f2/0x9b1 fs/xfs/libxfs/xfs_bmap.c:1098 xfs_attr_set+0xe38/0x12a7 fs/xfs/libxfs/xfs_attr.c:746 xfs_xattr_set+0xeb/0x1a9 fs/xfs/xfs_xattr.c:59 __vfs_setxattr+0x11b/0x177 fs/xattr.c:180 __vfs_setxattr_noperm+0x128/0x5e0 fs/xattr.c:214 __vfs_setxattr_locked+0x1d4/0x258 fs/xattr.c:275 vfs_setxattr+0x154/0x33d fs/xattr.c:301 setxattr+0x216/0x29f fs/xattr.c:575 __do_sys_fsetxattr fs/xattr.c:632 [inline] __se_sys_fsetxattr fs/xattr.c:621 [inline] __x64_sys_fsetxattr+0x243/0x2fe fs/xattr.c:621 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3a/0x7e arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0x0 Freed by task 2949: kasan_save_stack+0x19/0x38 mm/kasan/common.c:38 kasan_set_track+0x1c/0x21 mm/kasan/common.c:46 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:360 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free mm/kasan/common.c:328 [inline] __kasan_slab_free+0xe2/0x10e mm/kasan/common.c:374 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1700 [inline] slab_free_freelist_hook mm/slub.c:1726 [inline] slab_free mm/slub.c:3492 [inline] kmem_cache_free+0xdc/0x3ce mm/slub.c:3508 xfs_attr_fork_remove+0x8d/0x132 fs/xfs/libxfs/xfs_attr_leaf.c:773 xfs_attr_sf_removename+0x5dd/0x6cb fs/xfs/libxfs/xfs_attr_leaf.c:822 xfs_attr_remove_iter+0x68c/0x805 fs/xfs/libxfs/xfs_attr.c:1413 xfs_attr_remove_args+0xb1/0x10d fs/xfs/libxfs/xfs_attr.c:684 xfs_attr_set+0xf1e/0x12a7 fs/xfs/libxfs/xfs_attr.c:802 xfs_xattr_set+0xeb/0x1a9 fs/xfs/xfs_xattr.c:59 __vfs_removexattr+0x106/0x16a fs/xattr.c:468 cap_inode_killpriv+0x24/0x47 security/commoncap.c:324 security_inode_killpriv+0x54/0xa1 security/security.c:1414 setattr_prepare+0x1a6/0x897 fs/attr.c:146 xfs_vn_change_ok+0x111/0x15e fs/xfs/xfs_iops.c:682 xfs_vn_setattr_size+0x5f/0x15a fs/xfs/xfs_iops.c:1065 xfs_vn_setattr+0x125/0x2ad fs/xfs/xfs_iops.c:1093 notify_change+0xae5/0x10a1 fs/attr.c:410 do_truncate+0x134/0x1e0 fs/open.c:64 handle_truncate fs/namei.c:3084 [inline] do_open fs/namei.c:3432 [inline] path_openat+0x30ab/0x396d fs/namei.c:3561 do_filp_open+0x1c4/0x290 fs/namei.c:3588 do_sys_openat2+0x60d/0x98c fs/open.c:1212 do_sys_open+0xcf/0x13c fs/open.c:1228 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3a/0x7e arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0x0 The buggy address belongs to the object at ffff88802cec9188 which belongs to the cache xfs_ifork of size 40 The buggy address is located 20 bytes inside of 40-byte region [ffff88802cec9188, ffff88802cec91b0) The buggy address belongs to the page: page:00000000c3af36a1 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2cec9 flags: 0xfffffc0000200(slab|node=0|zone=1|lastcpupid=0x1fffff) raw: 000fffffc0000200 ffffea00009d2580 0000000600000006 ffff88801a9ffc80 raw: 0000000000000000 0000000080490049 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88802cec9080: fb fb fb fc fc fa fb fb fb fb fc fc fb fb fb fb ffff88802cec9100: fb fc fc fb fb fb fb fb fc fc fb fb fb fb fb fc >ffff88802cec9180: fc fa fb fb fb fb fc fc fa fb fb fb fb fc fc fb ^ ffff88802cec9200: fb fb fb fb fc fc fb fb fb fb fb fc fc fb fb fb ffff88802cec9280: fb fb fc fc fa fb fb fb fb fc fc fa fb fb fb fb ================================================================== The root cause of this bug is the unlocked access to xfs_inode.i_afp from the getxattr code paths while trying to determine which ILOCK mode to use to stabilize the xattr data. Unfortunately, the VFS does not acquire i_rwsem when vfs_getxattr (or listxattr) call into the filesystem, which means that getxattr can race with a removexattr that's tearing down the attr fork and crash: xfs_attr_set: xfs_attr_get: xfs_attr_fork_remove: xfs_ilock_attr_map_shared: xfs_idestroy_fork(ip->i_afp); kmem_cache_free(xfs_ifork_cache, ip->i_afp); if (ip->i_afp && ip->i_afp = NULL; xfs_need_iread_extents(ip->i_afp)) <KABOOM> ip->i_forkoff = 0; Regrettably, the VFS is much more lax about i_rwsem and getxattr than is immediately obvious -- not only does it not guarantee that we hold i_rwsem, it actually doesn't guarantee that we *don't* hold it either. The getxattr system call won't acquire the lock before calling XFS, but the file capabilities code calls getxattr with and without i_rwsem held to determine if the "security.capabilities" xattr is set on the file. Fixing the VFS locking requires a treewide investigation into every code path that could touch an xattr and what i_rwsem state it expects or sets up. That could take years or even prove impossible; fortunately, we can fix this UAF problem inside XFS. An earlier version of this patch used smp_wmb in xfs_attr_fork_remove to ensure that i_forkoff is always zeroed before i_afp is set to null and changed the read paths to use smp_rmb before accessing i_forkoff and i_afp, which avoided these UAF problems. However, the patch author was too busy dealing with other problems in the meantime, and by the time he came back to this issue, the situation had changed a bit. On a modern system with selinux, each inode will always have at least one xattr for the selinux label, so it doesn't make much sense to keep incurring the extra pointer dereference. Furthermore, Allison's upcoming parent pointer patchset will also cause nearly every inode in the filesystem to have extended attributes. Therefore, make the inode attribute fork structure part of struct xfs_inode, at a cost of 40 more bytes. This patch adds a clunky if_present field where necessary to maintain the existing logic of xattr fork null pointer testing in the existing codebase. The next patch switches the logic over to XFS_IFORK_Q and it all goes away. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-07-09xfs: convert XFS_IFORK_PTR to a static inline helperDarrick J. Wong
We're about to make this logic do a bit more, so convert the macro to a static inline function for better typechecking and fewer shouty macros. No functional changes here. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-04-21Merge tag 'large-extent-counters-v9' of https://github.com/chandanr/linux ↵Dave Chinner
into xfs-5.19-for-next xfs: Large extent counters The commit xfs: fix inode fork extent count overflow (3f8a4f1d876d3e3e49e50b0396eaffcc4ba71b08) mentions that 10 billion data fork extents should be possible to create. However the corresponding on-disk field has a signed 32-bit type. Hence this patchset extends the per-inode data fork extent counter to 64 bits (out of which 48 bits are used to store the extent count). Also, XFS has an attribute fork extent counter which is 16 bits wide. A workload that, 1. Creates 1 million 255-byte sized xattrs, 2. Deletes 50% of these xattrs in an alternating manner, 3. Tries to insert 400,000 new 255-byte sized xattrs causes the xattr extent counter to overflow. Dave tells me that there are instances where a single file has more than 100 million hardlinks. With parent pointers being stored in xattrs, we will overflow the signed 16-bits wide attribute extent counter when large number of hardlinks are created. Hence this patchset extends the on-disk field to 32-bits. The following changes are made to accomplish this, 1. A 64-bit inode field is carved out of existing di_pad and di_flushiter fields to hold the 64-bit data fork extent counter. 2. The existing 32-bit inode data fork extent counter will be used to hold the attribute fork extent counter. 3. A new incompat superblock flag to prevent older kernels from mounting the filesystem. Signed-off-by: Chandan Babu R <chandan.babu@oracle.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-04-21xfs: convert inode lock flags to unsigned.Dave Chinner
5.18 w/ std=gnu11 compiled with gcc-5 wants flags stored in unsigned fields to be unsigned. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Chandan Babu R <chandan.babu@oracle.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-04-11xfs: Introduce XFS_DIFLAG2_NREXT64 and associated helpersChandan Babu R
This commit adds the new per-inode flag XFS_DIFLAG2_NREXT64 to indicate that an inode supports 64-bit extent counters. This flag is also enabled by default on newly created inodes when the corresponding filesystem has large extent counter feature bit (i.e. XFS_FEAT_NREXT64) set. Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Chandan Babu R <chandan.babu@oracle.com>
2022-03-14xfs: constify the name argument to various directory functionsDarrick J. Wong
Various directory functions do not modify their @name parameter, so mark it const to make that clear. This will enable us to mark the global xfs_name_dotdot variable as const to prevent mischief. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-02-01xfs: move xfs_update_prealloc_flags() to xfs_pnfs.cDave Chinner
The operations that xfs_update_prealloc_flags() perform are now unique to xfs_fs_map_blocks(), so move xfs_update_prealloc_flags() to be a static function in xfs_pnfs.c and cut out all the other functionality that is doesn't use anymore. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2022-02-01xfs: remove XFS_PREALLOC_SYNCDave Chinner
Callers can acheive the same thing by calling xfs_log_force_inode() after making their modifications. There is no need for xfs_update_prealloc_flags() to do this. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-11-24xfs: remove xfs_inew_waitChristoph Hellwig
With the remove of xfs_dqrele_all_inodes, xfs_inew_wait and all the infrastructure used to wake the XFS_INEW bit waitqueue is unused. Reported-by: kernel test robot <lkp@intel.com> Fixes: 777eb1fa857e ("xfs: remove xfs_dqrele_all_inodes") Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-10-22xfs: rename _zone variables to _cacheDarrick J. Wong
Now that we've gotten rid of the kmem_zone_t typedef, rename the variables to _cache since that's what they are. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
2021-10-22xfs: remove kmem_zone typedefDarrick J. Wong
Remove these typedefs by referencing kmem_cache directly. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
2021-09-02Merge tag 'xfs-5.15-merge-6' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds
Pull xfs updates from Darrick Wong: "There's a lot in this cycle. Starting with bug fixes: To avoid livelocks between the logging code and the quota code, we've disabled the ability of quotaoff to turn off quota accounting. (Admins can still disable quota enforcement, but truly turning off accounting requires a remount.) We've tried to do this in a careful enough way that there shouldn't be any user visible effects aside from quotaoff no longer randomly hanging the system. We've also fixed some bugs in runtime log behavior that could trip up log recovery if (otherwise unrelated) transactions manage to start and commit concurrently; some bugs in the GETFSMAP ioctl where we would incorrectly restrict the range of records output if the two xfs devices are of different sizes; a bug that resulted in fallocate funshare failing unnecessarily; and broken behavior in the xfs inode cache when DONTCACHE is in play. As for new features: we now batch inode inactivations in percpu background threads, which sharply decreases frontend thread wait time when performing file deletions and should improve overall directory tree deletion times. This eliminates both the problem where closing an unlinked file (especially on a frozen fs) can stall for a long time, and should also ease complaints about direct reclaim bogging down on unlinked file cleanup. Starting with this release, we've enabled pipelining of the XFS log. On workloads with high rates of metadata updates to different shards of the filesystem, multiple threads can be used to format committed log updates into log checkpoints. Lastly, with this release, two new features have graduated to supported status: inode btree counters (for faster mounts), and support for dates beyond Y2038. Expect these to be enabled by default in a future release of xfsprogs. Summary: - Fix a potential log livelock on busy filesystems when there's so much work going on that we can't finish a quotaoff before filling up the log by removing the ability to disable quota accounting. - Introduce the ability to use per-CPU data structures in XFS so that we can do a better job of maintaining CPU locality for certain operations. - Defer inode inactivation work to per-CPU lists, which will help us batch that processing. Deletions of large sparse files will *appear* to run faster, but all that means is that we've moved the work to the backend. - Drop the EXPERIMENTAL warnings from the y2038+ support and the inode btree counters, since it's been nearly a year and no complaints have come in. - Remove more of our bespoke kmem* variants in favor of using the standard Linux calls. - Prepare for the addition of log incompat features in upcoming cycles by actually adding code to support this. - Small cleanups of the xattr code in preparation for landing support for full logging of extended attribute updates in a future cycle. - Replace the various log shutdown state and flag code all over xfs with a single atomic bit flag. - Fix a serious log recovery bug where log item replay can be skipped based on the start lsn of a transaction even though the transaction commit lsn is the key data point for that by enforcing start lsns to appear in the log in the same order as commit lsns. - Enable pipelining in the code that pushes log items to disk. - Drop ->writepage. - Fix some bugs in GETFSMAP where the last fsmap record reported for a device could extend beyond the end of the device, and a separate bug where query keys for one device could be applied to another. - Don't let GETFSMAP query functions edit their input parameters. - Small cleanups to the scrub code's handling of perag structures. - Small cleanups to the incore inode tree walk code. - Constify btree function parameters that aren't changed, so that there will never again be confusion about range query functions changing their input parameters. - Standardize the format and names of tracepoint data attributes. - Clean up all the mount state and feature flags to use wrapped bitset functions instead of inconsistently open-coded flag checks. - Fix some confusion between xfs_buf hash table key variable vs. block number. - Fix a mis-interaction with iomap where we reported shared delalloc cow fork extents to iomap, which would cause the iomap unshare operation to return IO errors unnecessarily. - Fix DONTCACHE behavior" * tag 'xfs-5.15-merge-6' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (103 commits) xfs: fix I_DONTCACHE xfs: only set IOMAP_F_SHARED when providing a srcmap to a write xfs: fix perag structure refcounting error when scrub fails xfs: rename buffer cache index variable b_bn xfs: convert bp->b_bn references to xfs_buf_daddr() xfs: introduce xfs_buf_daddr() xfs: kill xfs_sb_version_has_v3inode() xfs: introduce xfs_sb_is_v5 helper xfs: remove unused xfs_sb_version_has wrappers xfs: convert xfs_sb_version_has checks to use mount features xfs: convert scrub to use mount-based feature checks xfs: open code sb verifier feature checks xfs: convert xfs_fs_geometry to use mount feature checks xfs: replace XFS_FORCED_SHUTDOWN with xfs_is_shutdown xfs: convert remaining mount flags to state flags xfs: convert mount flags to features xfs: consolidate mount option features in m_features xfs: replace xfs_sb_version checks with feature flag checks xfs: reflect sb features in xfs_mount xfs: rework attr2 feature and mount options ...
2021-08-19xfs: convert mount flags to featuresDave Chinner
Replace m_flags feature checks with xfs_has_<feature>() calls and rework the setup code to set flags in m_features. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-08-06xfs: per-cpu deferred inode inactivation queuesDave Chinner
Move inode inactivation to background work contexts so that it no longer runs in the context that releases the final reference to an inode. This will allow process work that ends up blocking on inactivation to continue doing work while the filesytem processes the inactivation in the background. A typical demonstration of this is unlinking an inode with lots of extents. The extents are removed during inactivation, so this blocks the process that unlinked the inode from the directory structure. By moving the inactivation to the background process, the userspace applicaiton can keep working (e.g. unlinking the next inode in the directory) while the inactivation work on the previous inode is done by a different CPU. The implementation of the queue is relatively simple. We use a per-cpu lockless linked list (llist) to queue inodes for inactivation without requiring serialisation mechanisms, and a work item to allow the queue to be processed by a CPU bound worker thread. We also keep a count of the queue depth so that we can trigger work after a number of deferred inactivations have been queued. The use of a bound workqueue with a single work depth allows the workqueue to run one work item per CPU. We queue the work item on the CPU we are currently running on, and so this essentially gives us affine per-cpu worker threads for the per-cpu queues. THis maintains the effective CPU affinity that occurs within XFS at the AG level due to all objects in a directory being local to an AG. Hence inactivation work tends to run on the same CPU that last accessed all the objects that inactivation accesses and this maintains hot CPU caches for unlink workloads. A depth of 32 inodes was chosen to match the number of inodes in an inode cluster buffer. This hopefully allows sequential allocation/unlink behaviours to defering inactivation of all the inodes in a single cluster buffer at a time, further helping maintain hot CPU and buffer cache accesses while running inactivations. A hard per-cpu queue throttle of 256 inode has been set to avoid runaway queuing when inodes that take a long to time inactivate are being processed. For example, when unlinking inodes with large numbers of extents that can take a lot of processing to free. Signed-off-by: Dave Chinner <dchinner@redhat.com> [djwong: tweak comments and tracepoints, convert opflags to state bits] Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-08-06xfs: detach dquots from inode if we don't need to inactivate itDarrick J. Wong
If we don't need to inactivate an inode, we can detach the dquots and move on to reclamation. This isn't strictly required here; it's a preparation patch for deferred inactivation per reviewer request[1] to move the creation of xfs_inode_needs_inactivation into a separate change. Eventually this !need_inactive chunk will turn into the code path for inodes that skip xfs_inactive and go straight to memory reclaim. [1] https://lore.kernel.org/linux-xfs/20210609012838.GW2945738@locust/T/#mca6d958521cb88bbc1bfe1a30767203328d410b5 Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2021-07-13xfs: Convert to use invalidate_lockJan Kara
Use invalidate_lock instead of XFS internal i_mmap_lock. The intended purpose of invalidate_lock is exactly the same. Note that the locking in __xfs_filemap_fault() slightly changes as filemap_fault() already takes invalidate_lock. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> CC: <linux-xfs@vger.kernel.org> CC: "Darrick J. Wong" <djwong@kernel.org> Signed-off-by: Jan Kara <jack@suse.cz>
2021-07-13xfs: Refactor xfs_isilocked()Pavel Reichl
Introduce a new __xfs_rwsem_islocked predicate to encapsulate checking the state of a rw_semaphore, then refactor xfs_isilocked to use it. Signed-off-by: Pavel Reichl <preichl@redhat.com> Suggested-by: Dave Chinner <dchinner@redhat.com> Suggested-by: Eric Sandeen <sandeen@redhat.com> Suggested-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Jan Kara <jack@suse.cz>
2021-06-02xfs: get rid of xfs_dir_ialloc()Dave Chinner
This is just a simple wrapper around the per-ag inode allocation that doesn't need to exist. The internal mechanism to select and allocate within an AG does not need to be exposed outside xfs_ialloc.c, and it being exposed simply makes it harder to follow the code and simplify it. This is simplified by internalising xf_dialloc_select_ag() and xfs_dialloc_ag() into a single xfs_dialloc() function and then xfs_dir_ialloc() can go away. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>