lwn.git/fs/xfs, branch docs-5.8-2

xfs: reflink should force the log out if mounted with wsync

2020-04-06T15:44:39+00:00

Reflink should force the log out to disk if the filesystem was mounted with wsync, the same as most other operations in xfs. [Note: XFS_MOUNT_WSYNC is set when the admin mounts the filesystem with either the 'wsync' or 'sync' mount options, which effectively means that we're classifying reflink/dedupe as IO operations and making them synchronous when required.] Fixes: 3fc9f5e409319 ("xfs: remove xfs_reflink_remap_range") Signed-off-by: Christoph Hellwig Reviewed-by: Brian Foster [darrick: add more to the changelog] Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong

xfs: factor out a new xfs_log_force_inode helper

2020-04-06T15:44:35+00:00

Create a new helper to force the log up to the last LSN touching an inode. Signed-off-by: Christoph Hellwig Reviewed-by: Brian Foster Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong

xfs: fix inode number overflow in ifree cluster helper

2020-04-02T15:19:25+00:00

Qian Cai reports seemingly random buffer read verifier errors during filesystem writeback. This was isolated to a recent patch that factored out some inode cluster freeing code and happened to cast an unsigned inode number type to a signed value. If the inode number value overflows, we can skip marking in-core inodes associated with the underlying buffer stale at the time the physical inodes are freed. If such an inode happens to be dirty, xfsaild will eventually attempt to write it back over non-inode blocks. The invalidation of the underlying inode buffer causes writeback to read the buffer from disk. This fails the read verifier (preventing eventual corruption) if the buffer no longer looks like an inode cluster. Analysis by Dave Chinner. Fix up the helper to use the proper type for inode number values. Fixes: 5806165a6663 ("xfs: factor inode lookup from xfs_ifree_cluster") Reported-by: Qian Cai Signed-off-by: Brian Foster Reviewed-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong

xfs: remove redundant variable assignment in xfs_symlink()

2020-03-31T15:42:22+00:00

The variables 'udqp' and 'gdqp' have been initialized, so remove redundant variable assignment in xfs_symlink(). Signed-off-by: Kaixu Xia Reviewed-by: Chaitanya Kulkarni Reviewed-by: Dave Chinner Signed-off-by: Darrick J. Wong

xfs: ratelimit inode flush on buffered write ENOSPC

2020-03-31T15:41:45+00:00

A customer reported rcu stalls and softlockup warnings on a computer with many CPU cores and many many more IO threads trying to write to a filesystem that is totally out of space. Subsequent analysis pointed to the many many IO threads calling xfs_flush_inodes -> sync_inodes_sb, which causes a lot of wb_writeback_work to be queued. The writeback worker spends so much time trying to wake the many many threads waiting for writeback completion that it trips the softlockup detector, and (in this case) the system automatically reboots. In addition, they complain that the lengthy xfs_flush_inodes scan traps all of those threads in uninterruptible sleep, which hampers their ability to kill the program or do anything else to escape the situation. If there's thousands of threads trying to write to files on a full filesystem, each of those threads will start separate copies of the inode flush scan. This is kind of pointless since we only need one scan, so rate limit the inode flush. Signed-off-by: Darrick J. Wong Reviewed-by: Dave Chinner

xfs: return locked status of inode buffer on xfsaild push

2020-03-28T16:40:12+00:00

If the inode buffer backing a particular inode is locked, xfs_iflush() returns -EAGAIN and xfs_inode_item_push() skips the inode. It still returns success to xfsaild, however, which bypasses the xfsaild backoff heuristic. Update xfs_inode_item_push() to return locked status if the inode buffer couldn't be locked. Signed-off-by: Brian Foster Reviewed-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong

xfs: trylock underlying buffer on dquot flush

2020-03-28T16:40:11+00:00

A dquot flush currently blocks on the buffer lock for the underlying dquot buffer. In turn, this causes xfsaild to block rather than continue processing other items in the meantime. Update xfs_qm_dqflush() to trylock the buffer, similar to how inode buffers are handled, and return -EAGAIN if the lock fails. Fix up any callers that don't currently handle the error properly. Signed-off-by: Brian Foster Reviewed-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong

xfs: remove unnecessary ternary from xfs_create

2020-03-28T16:40:11+00:00

Since the "no-allocation" reservations for file creations has been removed, the resblks value should be larger than zero, so remove unnecessary ternary conditional. Signed-off-by: Kaixu Xia Reviewed-by: Christoph Hellwig Reviewed-by: Darrick J. Wong [darrick: s/judgment/ternary/] Signed-off-by: Darrick J. Wong

xfs: don't write a corrupt unmount record to force summary counter recalc

2020-03-27T15:32:55+00:00

In commit f467cad95f5e3, I added the ability to force a recalculation of the filesystem summary counters if they seemed incorrect. This was done (not entirely correctly) by tweaking the log code to write an unmount record without the UMOUNT_TRANS flag set. At next mount, the log recovery code will fail to find the unmount record and go into recovery, which triggers the recalculation. What actually gets written to the log is what ought to be an unmount record, but without any flags set to indicate what kind of record it actually is. This worked to trigger the recalculation, but we shouldn't write bogus log records when we could simply write nothing. Fixes: f467cad95f5e3 ("xfs: force summary counter recalc at next mount") Signed-off-by: Darrick J. Wong Reviewed-by: Christoph Hellwig Reviewed-by: Brian Foster

xfs: factor inode lookup from xfs_ifree_cluster

2020-03-27T15:32:55+00:00

There's lots of indent in this code which makes it a bit hard to follow. We are also going to completely rework the inode lookup code as part of the inode reclaim rework, so factor out the inode lookup code from the inode cluster freeing code. Based on prototype code from Christoph Hellwig. Signed-off-by: Dave Chinner Reviewed-by: Brian Foster Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong