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2018-01-30Merge tag 'iversion-v4.16-1' of ↵Linus Torvalds1-2/+3
git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux Pull inode->i_version rework from Jeff Layton: "This pile of patches is a rework of the inode->i_version field. We have traditionally incremented that field on every inode data or metadata change. Typically this increment needs to be logged on disk even when nothing else has changed, which is rather expensive. It turns out though that none of the consumers of that field actually require this behavior. The only real requirement for all of them is that it be different iff the inode has changed since the last time the field was checked. Given that, we can optimize away most of the i_version increments and avoid dirtying inode metadata when the only change is to the i_version and no one is querying it. Queries of the i_version field are rather rare, so we can help write performance under many common workloads. This patch series converts existing accesses of the i_version field to a new API, and then converts all of the in-kernel filesystems to use it. The last patch in the series then converts the backend implementation to a scheme that optimizes away a large portion of the metadata updates when no one is looking at it. In my own testing this series significantly helps performance with small I/O sizes. I also got this email for Christmas this year from the kernel test robot (a 244% r/w bandwidth improvement with XFS over DAX, with 4k writes): https://lkml.org/lkml/2017/12/25/8 A few of the earlier patches in this pile are also flowing to you via other trees (mm, integrity, and nfsd trees in particular)". * tag 'iversion-v4.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux: (22 commits) fs: handle inode->i_version more efficiently btrfs: only dirty the inode in btrfs_update_time if something was changed xfs: avoid setting XFS_ILOG_CORE if i_version doesn't need incrementing fs: only set S_VERSION when updating times if necessary IMA: switch IMA over to new i_version API xfs: convert to new i_version API ufs: use new i_version API ocfs2: convert to new i_version API nfsd: convert to new i_version API nfs: convert to new i_version API ext4: convert to new i_version API ext2: convert to new i_version API exofs: switch to new i_version API btrfs: convert to new i_version API afs: convert to new i_version API affs: convert to new i_version API fat: convert to new i_version API fs: don't take the i_lock in inode_inc_iversion fs: new API for handling inode->i_version ntfs: remove i_version handling ...
2018-01-29xfs: convert to new i_version APIJeff Layton1-2/+3
Signed-off-by: Jeff Layton <jlayton@redhat.com> Acked-by: Darrick J. Wong <darrick.wong@oracle.com> Acked-by: Dave Chinner <dchinner@redhat.com>
2017-12-21xfs: remove leftover CoW reservations when remounting roDarrick J. Wong1-1/+1
When we're remounting the filesystem readonly, remove all CoW preallocations prior to going ro. If the fs goes down after the ro remount, we never clean up the staging extents, which means xfs_check will trip over them on a subsequent run. Practically speaking, the next mount will clean them up too, so this is unlikely to be seen. Since we shut down the cowblocks cleaner on remount-ro, we also have to make sure we start it back up if/when we remount-rw. Found by adding clonerange to fsstress and running xfs/017. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2017-12-21xfs: track cowblocks separately in i_flagsDarrick J. Wong1-9/+24
The EOFBLOCKS/COWBLOCKS tags are totally separate things, so track them with separate i_flags. Right now we're abusing IEOFBLOCKS for both, which is totally bogus because we won't tag the inode with COWBLOCKS if IEOFBLOCKS was set by a previous tagging of the inode with EOFBLOCKS. Found by wiring up clonerange to fsstress in xfs/017. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2017-10-27xfs: return a distinct error code value for IGET_INCORE cache missesDarrick J. Wong1-1/+1
For an XFS_IGET_INCORE iget operation, if the inode isn't in the cache, return ENODATA so that we don't confuse it with the pre-existing ENOENT cases (inode is in cache, but freed). Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2017-09-01xfs: check for race with xfs_reclaim_inode() in xfs_ifree_cluster()Omar Sandoval1-5/+5
After xfs_ifree_cluster() finds an inode in the radix tree and verifies that the inode number is what it expected, xfs_reclaim_inode() can swoop in and free it. xfs_ifree_cluster() will then happily continue working on the freed inode. Most importantly, it will mark the inode stale, which will probably be overwritten when the inode slab object is reallocated, but if it has already been reallocated then we can end up with an inode spuriously marked stale. In 8a17d7ddedb4 ("xfs: mark reclaimed inodes invalid earlier") we added a second check to xfs_iflush_cluster() to detect this race, but the similar RCU lookup in xfs_ifree_cluster() needs the same treatment. Signed-off-by: Omar Sandoval <osandov@fb.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-07-10Merge tag 'xfs-4.13-merge-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds1-2/+50
Pull XFS updates from Darrick Wong: "Here are some changes for you for 4.13. For the most part it's fixes for bugs and deadlock problems, and preparation for online fsck in some future merge window. - Avoid quotacheck deadlocks - Fix transaction overflows when bunmapping fragmented files - Refactor directory readahead - Allow admin to configure if ASSERT is fatal - Improve transaction usage detail logging during overflows - Minor cleanups - Don't leak log items when the log shuts down - Remove double-underscore typedefs - Various preparation for online scrubbing - Introduce new error injection configuration sysfs knobs - Refactor dq_get_next to use extent map directly - Fix problems with iterating the page cache for unwritten data - Implement SEEK_{HOLE,DATA} via iomap - Refactor XFS to use iomap SEEK_HOLE and SEEK_DATA - Don't use MAXPATHLEN to check on-disk symlink target lengths" * tag 'xfs-4.13-merge-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (48 commits) xfs: don't crash on unexpected holes in dir/attr btrees xfs: rename MAXPATHLEN to XFS_SYMLINK_MAXLEN xfs: fix contiguous dquot chunk iteration livelock xfs: Switch to iomap for SEEK_HOLE / SEEK_DATA vfs: Add iomap_seek_hole and iomap_seek_data helpers vfs: Add page_cache_seek_hole_data helper xfs: remove a whitespace-only line from xfs_fs_get_nextdqblk xfs: rewrite xfs_dq_get_next_id using xfs_iext_lookup_extent xfs: Check for m_errortag initialization in xfs_errortag_test xfs: grab dquots without taking the ilock xfs: fix semicolon.cocci warnings xfs: Don't clear SGID when inheriting ACLs xfs: free cowblocks and retry on buffered write ENOSPC xfs: replace log_badcrc_factor knob with error injection tag xfs: convert drop_writes to use the errortag mechanism xfs: remove unneeded parameter from XFS_TEST_ERROR xfs: expose errortag knobs via sysfs xfs: make errortag a per-mountpoint structure xfs: free uncommitted transactions during log recovery xfs: don't allow bmap on rt files ...
2017-06-20sched/wait: Standardize 'struct wait_bit_queue' wait-queue entry field nameIngo Molnar1-2/+2
Rename 'struct wait_bit_queue::wait' to ::wq_entry, to more clearly name it as a wait-queue entry. Propagate it to a couple of usage sites where the wait-bit-queue internals are exposed. Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-20xfs: check if an inode is cached and allocatedDarrick J. Wong1-2/+50
Check the inode cache for a particular inode number. If it's in the cache, check that it's not currently being reclaimed. If it's not being reclaimed, return zero if the inode is allocated. This function will be used by various scrubbers to decide if the cache is more up to date than the disk in terms of checking if an inode is allocated. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2017-06-08xfs: fix spurious spin_is_locked() assert failures on non-smp kernelsBrian Foster1-3/+2
The 0-day kernel test robot reports assertion failures on !CONFIG_SMP kernels due to failed spin_is_locked() checks. As it turns out, spin_is_locked() is hardcoded to return zero on !CONFIG_SMP kernels and so this function cannot be relied on to verify spinlock state in this configuration. To avoid this problem, replace the associated asserts with lockdep variants that do the right thing regardless of kernel configuration. Drop the one assert that checks for an unlocked lock as there is no suitable lockdep variant for that case. This moves the spinlock checks from XFS debug code to lockdep, but generally provides the same level of protection. Reported-by: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-04-28xfs: update ag iterator to support wait on new inodesBrian Foster1-8/+45
The AG inode iterator currently skips new inodes as such inodes are inserted into the inode radix tree before they are fully constructed. Certain contexts require the ability to wait on the construction of new inodes, however. The fs-wide dquot release from the quotaoff sequence is an example of this. Update the AG inode iterator to support the ability to wait on inodes flagged with XFS_INEW upon request. Create a new xfs_inode_ag_iterator_flags() interface and support a set of iteration flags to modify the iteration behavior. When the XFS_AGITER_INEW_WAIT flag is set, include XFS_INEW flags in the radix tree inode lookup and wait on them before the callback is executed. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-04-28xfs: support ability to wait on new inodesBrian Foster1-1/+4
Inodes that are inserted into the perag tree but still under construction are flagged with the XFS_INEW bit. Most contexts either skip such inodes when they are encountered or have the ability to handle them. The runtime quotaoff sequence introduces a context that must wait for construction of such inodes to correctly ensure that all dquots in the fs are released. In anticipation of this, support the ability to wait on new inodes. Wake the appropriate bit when XFS_INEW is cleared. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-03-08xfs: only reclaim unwritten COW extents periodicallyChristoph Hellwig1-1/+1
We only want to reclaim preallocations from our periodic work item. Currently this is archived by looking for a dirty inode, but that check is rather fragile. Instead add a flag to xfs_reflink_cancel_cow_* so that the caller can ask for just cancelling unwritten extents in the COW fork. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> [darrick: fix typos in commit message] Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-01-31xfs: sync eofblocks scans under iolock are livelock proneBrian Foster1-38/+7
The xfs_eofblocks.eof_scan_owner field is an internal field to facilitate invoking eofb scans from the kernel while under the iolock. This is necessary because the eofb scan acquires the iolock of each inode. Synchronous scans are invoked on certain buffered write failures while under iolock. In such cases, the scan owner indicates that the context for the scan already owns the particular iolock and prevents a double lock deadlock. eofblocks scans while under iolock are still livelock prone in the event of multiple parallel scans, however. If multiple buffered writes to different inodes fail and invoke eofblocks scans at the same time, each scan avoids a deadlock with its own inode by virtue of the eof_scan_owner field, but will never be able to acquire the iolock of the inode from the parallel scan. Because the low free space scans are invoked with SYNC_WAIT, the scan will not return until it has processed every tagged inode and thus both scans will spin indefinitely on the iolock being held across the opposite scan. This problem can be reproduced reliably by generic/224 on systems with higher cpu counts (x16). To avoid this problem, simplify the semantics of eofblocks scans to never invoke a scan while under iolock. This means that the buffered write context must drop the iolock before the scan. It must reacquire the lock before the write retry and also repeat the initial write checks, as the original state might no longer be valid once the iolock was dropped. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-01-31xfs: pull up iolock from xfs_free_eofblocks()Brian Foster1-9/+15
xfs_free_eofblocks() requires the IOLOCK_EXCL lock, but is called from different contexts where the lock may or may not be held. The need_iolock parameter exists for this reason, to indicate whether xfs_free_eofblocks() must acquire the iolock itself before it can proceed. This is ugly and confusing. Simplify the semantics of xfs_free_eofblocks() to require the caller to acquire the iolock appropriately and kill the need_iolock parameter. While here, the mp param can be removed as well as the xfs_mount is accessible from the xfs_inode structure. This patch does not change behavior. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-01-04xfs: fix crash and data corruption due to removal of busy COW extentsChristoph Hellwig1-1/+2
There is a race window between write_cache_pages calling clear_page_dirty_for_io and XFS calling set_page_writeback, in which the mapping for an inode is tagged neither as dirty, nor as writeback. If the COW shrinker hits in exactly that window we'll remove the delayed COW extents and writepages trying to write it back, which in release kernels will manifest as corruption of the bmap btree, and in debug kernels will trip the ASSERT about now calling xfs_bmapi_write with the COWFORK flag for holes. A complex customer load manages to hit this window fairly reliably, probably by always having COW writeback in flight while the cow shrinker runs. This patch adds another check for having the I_DIRTY_PAGES flag set, which is still set during this race window. While this fixes the problem I'm still not overly happy about the way the COW shrinker works as it still seems a bit fragile. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2016-11-30xfs: remove i_iolock and use i_rwsem in the VFS inode insteadChristoph Hellwig1-4/+2
This patch drops the XFS-own i_iolock and uses the VFS i_rwsem which recently replaced i_mutex instead. This means we only have to take one lock instead of two in many fast path operations, and we can also shrink the xfs_inode structure. Thanks to the xfs_ilock family there is very little churn, the only thing of note is that we need to switch to use the lock_two_directory helper for taking the i_rwsem on two inodes in a few places to make sure our lock order matches the one used in the VFS. Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Jens Axboe <axboe@fb.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-11-10xfs: fix unbalanced inode reclaim flush lockingBrian Foster1-13/+14
Filesystem shutdown testing on an older distro kernel has uncovered an imbalanced locking pattern for the inode flush lock in xfs_reclaim_inode(). Specifically, there is a double unlock sequence between the call to xfs_iflush_abort() and xfs_reclaim_inode() at the "reclaim:" label. This actually does not cause obvious problems on current kernels due to the current flush lock implementation. Older kernels use a counting based flush lock mechanism, however, which effectively breaks the lock indefinitely when an already unlocked flush lock is repeatedly unlocked. Though this only currently occurs on filesystem shutdown, it has reproduced the effect of elevating an fs shutdown to a system-wide crash or hang. As it turns out, the flush lock is not actually required for the reclaim logic in xfs_reclaim_inode() because by that time we have already cycled the flush lock once while holding ILOCK_EXCL. Therefore, remove the additional flush lock/unlock cycle around the 'reclaim:' label and update branches into this label to release the flush lock where appropriate. Add an assert to xfs_ifunlock() to help prevent future occurences of the same problem. Reported-by: Zorro Lang <zlang@redhat.com> Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-11-08xfs: don't skip cow forks w/ delalloc blocks in cowblocks scanBrian Foster1-1/+6
The cowblocks background scanner currently clears the cowblocks tag for inodes without any real allocations in the cow fork. This excludes inodes with only delalloc blocks in the cow fork. While we might never expect to clear delalloc blocks from the cow fork in the background scanner, it is not necessarily correct to clear the cowblocks tag from such inodes. For example, if the background scanner happens to process an inode between a buffered write and writeback, the scanner catches the inode in a state after delalloc blocks have been allocated to the cow fork but before the delalloc blocks have been converted to real blocks by writeback. The background scanner then incorrectly clears the cowblocks tag, even if part of the aforementioned delalloc reservation will not be remapped to the data fork (i.e., extra blocks due to the cowextsize hint). This means that any such additional blocks in the cow fork might never be reclaimed by the background scanner and could persist until the inode itself is reclaimed. To address this problem, only skip and clear inodes without any cow fork allocations whatsoever from the background scanner. While we generally do not want to cancel delalloc reservations from the background scanner, the pagecache dirty check following the cowblocks check should prevent that situation. If we do end up with delalloc cow fork blocks without a dirty address space mapping, this is probably an indication that something has gone wrong and the blocks should be reclaimed, as they may never be converted to a real allocation. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-10-24xfs: fix up inode cowblocks tracking tracepointsBrian Foster1-4/+4
These calls are still using the eofblocks tracepoints. The cowblocks equivalents are already defined, we just aren't actually calling them. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-10-06xfs: garbage collect old cowextsz reservationsDarrick J. Wong1-29/+209
Trim CoW reservations made on behalf of a cowextsz hint if they get too old or we run low on quota, so long as we don't have dirty data awaiting writeback or directio operations in progress. Garbage collection of the cowextsize extents are kept separate from prealloc extent reaping because setting the CoW prealloc lifetime to a (much) higher value than the regular prealloc extent lifetime has been useful for combatting CoW fragmentation on VM hosts where the VMs experience bursty write behaviors and we can keep the utilization ratios low enough that we don't start to run out of space. IOWs, it benefits us to keep the CoW fork reservations around for as long as we can unless we run out of blocks or hit inode reclaim. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-05xfs: introduce the CoW forkDarrick J. Wong1-0/+5
Introduce a new in-core fork for storing copy-on-write delalloc reservations and allocated extents that are in the process of being written out. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-09-19xfs: make xfs_inode_set_eofblocks_tag cheaper for the common caseChristoph Hellwig1-0/+14
For long growing file writes we will usually already have the eofblocks tag set when adding more speculative preallocations. Add a flag in the inode to allow us to skip the the fairly expensive AG-wide spinlocks and multiple radix tree operations in that case. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-06-21xfs: cancel eofblocks background trimming on remount read-onlyBrian Foster1-1/+1
The filesystem quiesce sequence performs the operations necessary to drain all background work, push pending transactions through the log infrastructure and wait on I/O resulting from the final AIL push. We have had reports of remount,ro hangs in xfs_log_quiesce() -> xfs_wait_buftarg(), however, and some instrumentation code to detect transaction commits at this point in the quiesce sequence has inculpated the eofblocks background scanner as a cause. While higher level remount code generally prevents user modifications by the time the filesystem has made it to xfs_log_quiesce(), the background scanner may still be alive and can perform pending work at any time. If this occurs between the xfs_log_force() and xfs_wait_buftarg() calls within xfs_log_quiesce(), this can lead to an indefinite lockup in xfs_wait_buftarg(). To prevent this problem, cancel the background eofblocks scan worker during the remount read-only quiesce sequence. This suspends background trimming when a filesystem is remounted read-only. This is only done in the remount path because the freeze codepath has already locked out new transactions by the time the filesystem attempts to quiesce (and thus waiting on an active work item could deadlock). Kick the eofblocks worker to pick up where it left off once an fs is remounted back to read-write. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-05-18xfs: move reclaim tagging functionsDave Chinner1-118/+116
Rearrange the inode tagging functions so that they are higher up in xfs_cache.c and so there is no need for forward prototypes to be defined. This is purely code movement, no other change. Signed-off-by: Dave Chinner <dchinner@redhat.com>
2016-05-18xfs: simplify inode reclaim tagging interfacesDave Chinner1-48/+50
Inode radix tree tagging for reclaim passes a lot of unnecessary variables around. Over time the xfs-perag has grown a xfs_mount backpointer, and an internal agno so we don't need to pass other variables into the tagging functions to supply this information. Rework the functions to pass the minimal variable set required and simplify the internal logic and flow. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-05-18xfs: mark reclaimed inodes invalid earlierDave Chinner1-12/+34
The last thing we do before using call_rcu() on an xfs_inode to be freed is mark it as invalid. This means there is a window between when we know for certain that the inode is going to be freed and when we do actually mark it as "freed". This is important in the context of RCU lookups - we can look up the inode, find that it is valid, and then use it as such not realising that it is in the final stages of being freed. As such, mark the inode as being invalid the moment we know it is going to be reclaimed. This can be done while we still hold the XFS_ILOCK_EXCL and the flush lock in xfs_inode_reclaim, meaning that it occurs well before we remove it from the radix tree, and that the i_flags_lock, the XFS_ILOCK and the inode flush lock all act as synchronisation points for detecting that an inode is about to go away. For defensive purposes, this allows us to add a further check to xfs_iflush_cluster to ensure we skip inodes that are being freed after we grab the XFS_ILOCK_SHARED and the flush lock - we know that if the inode number if valid while we have these locks held we know that it has not progressed through reclaim to the point where it is clean and is about to be freed. [bfoster: fixed __xfs_inode_clear_reclaim() using ip->i_ino after it had already been zeroed.] Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-05-18xfs: xfs_inode_free() isn't RCU safeDave Chinner1-7/+7
The xfs_inode freed in xfs_inode_free() has multiple allocated structures attached to it. We free these in xfs_inode_free() before we mark the inode as invalid, and before we run call_rcu() to queue the structure for freeing. Unfortunately, this freeing can race with other accesses that are in the RCU current grace period that have found the inode in the radix tree with a valid state. This includes xfs_iflush_cluster(), which calls xfs_inode_clean(), and that accesses the inode log item on the xfs_inode. The log item structure is freed in xfs_inode_free(), so there is the possibility we can be accessing freed memory in xfs_iflush_cluster() after validating the xfs_inode structure as being valid for this RCU context. Hence we can get spuriously incorrect clean state returned from such checks. This can lead to use thinking the inode is dirty when it is, in fact, clean, and so incorrectly attaching it to the buffer for IO and completion processing. This then leads to use-after-free situations on the xfs_inode itself if the IO completes after the current RCU grace period expires. The buffer callbacks will access the xfs_inode and try to do all sorts of things it shouldn't with freed memory. IOWs, xfs_iflush_cluster() only works correctly when racing with inode reclaim if the inode log item is present and correctly stating the inode is clean. If the inode is being freed, then reclaim has already made sure the inode is clean, and hence xfs_iflush_cluster can skip it. However, we are accessing the inode inode under RCU read lock protection and so also must ensure that all dynamically allocated memory we reference in this context is not freed until the RCU grace period expires. To fix this, move all the potential memory freeing into xfs_inode_free_callback() so that we are guarantee RCU protected lookup code will always have the memory structures it needs available during the RCU grace period that lookup races can occur in. Discovered-by: Brain Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-02-09xfs: mode di_mode to vfs inodeDave Chinner1-4/+9
Move the di_mode value from the xfs_icdinode to the VFS inode, reducing the xfs_icdinode byte another 2 bytes and collapsing another 2 byte hole in the structure. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-02-09xfs: move di_changecount to VFS inodeDave Chinner1-2/+4
We can store the di_changecount in the i_version field of the VFS inode and remove another 8 bytes from the xfs_icdinode. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-02-09xfs: move inode generation count to VFS inodeDave Chinner1-0/+2
Pull another 4 bytes out of the xfs_icdinode. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-02-09xfs: use vfs inode nlink field everywhereDave Chinner1-0/+2
The VFS tracks the inode nlink just like the xfs_icdinode. We can remove the variable from the icdinode and use the VFS inode variable everywhere, reducing the size of the xfs_icdinode by a further 4 bytes. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-02-09xfs: reinitialise recycled VFS inode correctlyDave Chinner1-1/+21
We are going to keep certain on-disk information in the VFS inode rather than in a separate XFS specific stucture, so we have to be careful of the VFS code clearing that information when we re-initialise reclaimable cached inodes during lookup. If we don't do this, then we lose critical information from the inode and that results in corruption being detected. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-02-09xfs: introduce inode log format objectDave Chinner1-1/+1
We currently carry around and log an entire inode core in the struct xfs_inode. A lot of the information in the inode core is duplicated in the VFS inode, but we cannot remove this duplication of infomration because the inode core is logged directly in xfs_inode_item_format(). Add a new function xfs_inode_item_format_core() that copies the inode core data into a struct xfs_icdinode that is pulled directly from the log vector buffer. This means we no longer directly copy the inode core, but copy the structures one member at a time. This will be slightly less efficient than copying, but will allow us to remove duplicate and unnecessary items from the struct xfs_inode. To enable us to do this, call the new structure a xfs_log_dinode, so that we know it's different to the physical xfs_dinode and the in-core xfs_icdinode. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-10-12xfs: per-filesystem stats counter implementationBill O'Donnell1-9/+9
This patch modifies the stats counting macros and the callers to those macros to properly increment, decrement, and add-to the xfs stats counts. The counts for global and per-fs stats are correctly advanced, and cleared by writing a "1" to the corresponding clear file. global counts: /sys/fs/xfs/stats/stats per-fs counts: /sys/fs/xfs/sda*/stats/stats global clear: /sys/fs/xfs/stats/stats_clear per-fs clear: /sys/fs/xfs/sda*/stats/stats_clear [dchinner: cleaned up macro variables, removed CONFIG_FS_PROC around stats structures and macros. ] Signed-off-by: Bill O'Donnell <billodo@redhat.com> Reviewed-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-08-28xfs: add mssing inode cache attempts counter incrementLucas Stach1-0/+2
Increasing the inode cache attempt counter was apparently dropped while refactoring the cache code and so stayed at the initial 0 value. Add the increment back to make the runtime stats more useful. Signed-off-by: Lucas Stach <dev@lynxeye.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23xfs: inodes are new until the dentry cache is set upDave Chinner1-2/+2
Al Viro noticed a generic set of issues to do with filehandle lookup racing with dentry cache setup. They involve a filehandle lookup occurring while an inode is being created and the filehandle lookup racing with the dentry creation for the real file. This can lead to multiple dentries for the one path being instantiated. There are a host of other issues around this same set of paths. The underlying cause is that file handle lookup only waits on inode cache instantiation rather than full dentry cache instantiation. XFS is mostly immune to the problems discovered due to it's own internal inode cache, but there are a couple of corner cases where races can happen. We currently clear the XFS_INEW flag when the inode is fully set up after insertion into the cache. Newly allocated inodes are inserted locked and so aren't usable until the allocation transaction commits. This, however, occurs before the dentry and security information is fully initialised and hence the inode is unlocked and available for lookups to find too early. To solve the problem, only clear the XFS_INEW flag for newly created inodes once the dentry is fully instantiated. This means lookups will retry until the XFS_INEW flag is removed from the inode and hence avoids the race conditions in questions. THis also means that xfs_create(), xfs_create_tmpfile() and xfs_symlink() need to finish the setup of the inode in their error paths if we had allocated the inode but failed later in the creation process. xfs_symlink(), in particular, needed a lot of help to make it's error handling match that of xfs_create(). Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-12-04Merge branch 'xfs-misc-fixes-for-3.19-2' into for-nextDave Chinner1-0/+2
Conflicts: fs/xfs/xfs_iops.c
2014-12-04xfs: active inodes stat is brokenDave Chinner1-0/+2
vn_active only ever gets decremented, so it has a very large negative number. Make it track the inode count we currently have allocated properly so we can easily track the size of the inode cache via tools like PCP. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-11-28xfs: merge xfs_inum.h into xfs_format.hChristoph Hellwig1-1/+0
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-11-28xfs: merge xfs_ag.h into xfs_format.hChristoph Hellwig1-1/+0
More on-disk format consolidation. A few declarations that weren't on-disk format related move into better suitable spots. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-23xfs: remove second xfs_quota.h inclusion in xfs_icache.cFabian Frederick1-1/+0
xfs_quota.h was included twice. Signed-off-by: Fabian Frederick <fabf@skynet.be> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-24xfs: run an eofblocks scan on ENOSPC/EDQUOTBrian Foster1-0/+52
From: Brian Foster <bfoster@redhat.com> Speculative preallocation and and the associated throttling metrics assume we're working with large files on large filesystems. Users have reported inefficiencies in these mechanisms when we happen to be dealing with large files on smaller filesystems. This can occur because while prealloc throttling is aggressive under low free space conditions, it is not active until we reach 5% free space or less. For example, a 40GB filesystem has enough space for several files large enough to have multi-GB preallocations at any given time. If those files are slow growing, they might reserve preallocation for long periods of time as well as avoid the background scanner due to frequent modification. If a new file is written under these conditions, said file has no access to this already reserved space and premature ENOSPC is imminent. To handle this scenario, modify the buffered write ENOSPC handling and retry sequence to invoke an eofblocks scan. In the smaller filesystem scenario, the eofblocks scan resets the usage of preallocation such that when the 5% free space threshold is met, throttling effectively takes over to provide fair and efficient preallocation until legitimate ENOSPC. The eofblocks scan is selective based on the nature of the failure. For example, an EDQUOT failure in a particular quota will use a filtered scan for that quota. Because we don't know which quota might have caused an allocation failure at any given time, we include each applicable quota determined to be under low free space conditions in the scan. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-24xfs: support a union-based filter for eofblocks scansBrian Foster1-1/+30
From: Brian Foster <bfoster@redhat.com> The eofblocks scan inode filter uses intersection logic by default. E.g., specifying both user and group quota ids filters out inodes that are not covered by both the specified user and group quotas. This is suitable for behavior exposed to userspace. Scans that are initiated from within the kernel might require more broad semantics, such as scanning all inodes under each quota associated with an inode to alleviate low free space conditions in each. Create the XFS_EOF_FLAGS_UNION flag to support a conditional union-based filtering algorithm for eofblocks scans. This flag is intentionally left out of the valid mask as it is not supported for scans initiated from userspace. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-24xfs: add scan owner field to xfs_eofblocksBrian Foster1-1/+12
From: Brian Foster <bfoster@redhat.com> The scan owner field represents an optional inode number that is responsible for the current scan. The purpose is to identify that an inode is under iolock and as such, the iolock shouldn't be attempted when trimming eofblocks. This is an internal only field. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-25xfs: global error sign conversionDave Chinner1-23/+23
Convert all the errors the core XFs code to negative error signs like the rest of the kernel and remove all the sign conversion we do in the interface layers. Errors for conversion (and comparison) found via searches like: $ git grep " E" fs/xfs $ git grep "return E" fs/xfs $ git grep " E[A-Z].*;$" fs/xfs Negation points found via searches like: $ git grep "= -[a-z,A-Z]" fs/xfs $ git grep "return -[a-z,A-D,F-Z]" fs/xfs $ git grep " -[a-z].*;" fs/xfs [ with some bits I missed from Brian Foster ] Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-22xfs: Nuke XFS_ERROR macroEric Sandeen1-3/+3
XFS_ERROR was designed long ago to trap return values, but it's not runtime configurable, it's not consistently used, and we can do similar error trapping with ftrace scripts and triggers from userspace. Just nuke XFS_ERROR and associated bits. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-04-14xfs: remove unused pag ptr arg from iterator execute functionsEric Sandeen1-8/+4
Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2013-10-24xfs: decouple inode and bmap btree header filesDave Chinner1-4/+0
Currently the xfs_inode.h header has a dependency on the definition of the BMAP btree records as the inode fork includes an array of xfs_bmbt_rec_host_t objects in it's definition. Move all the btree format definitions from xfs_btree.h, xfs_bmap_btree.h, xfs_alloc_btree.h and xfs_ialloc_btree.h to xfs_format.h to continue the process of centralising the on-disk format definitions. With this done, the xfs inode definitions are no longer dependent on btree header files. The enables a massive culling of unnecessary includes, with close to 200 #include directives removed from the XFS kernel code base. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Ben Myers <bpm@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2013-10-24xfs: decouple log and transaction headersDave Chinner1-5/+4
xfs_trans.h has a dependency on xfs_log.h for a couple of structures. Most code that does transactions doesn't need to know anything about the log, but this dependency means that they have to include xfs_log.h. Decouple the xfs_trans.h and xfs_log.h header files and clean up the includes to be in dependency order. In doing this, remove the direct include of xfs_trans_reserve.h from xfs_trans.h so that we remove the dependency between xfs_trans.h and xfs_mount.h. Hence the xfs_trans.h include can be moved to the indicate the actual dependencies other header files have on it. Note that these are kernel only header files, so this does not translate to any userspace changes at all. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Ben Myers <bpm@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>