diff options
author | Christoph Hellwig <hch@lst.de> | 2018-03-01 14:12:45 -0800 |
---|---|---|
committer | Darrick J. Wong <darrick.wong@oracle.com> | 2018-03-01 14:12:45 -0800 |
commit | ff3d8b9c4cb95180ae6ef9eed28409840525b9fa (patch) | |
tree | 14585938c73fbce45ff05877544aaab6e2c17503 /fs | |
parent | af5b5afe9ac68406892fa343fafba4ea988c3c69 (diff) |
xfs: don't block on the ilock for RWF_NOWAIT
Fix xfs_file_iomap_begin to trylock the ilock if IOMAP_NOWAIT is passed,
so that we don't block io_submit callers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Diffstat (limited to 'fs')
-rw-r--r-- | fs/xfs/xfs_iomap.c | 27 |
1 files changed, 19 insertions, 8 deletions
diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c index ee01859b77a5..046469fcc1b8 100644 --- a/fs/xfs/xfs_iomap.c +++ b/fs/xfs/xfs_iomap.c @@ -970,6 +970,15 @@ static inline bool need_excl_ilock(struct xfs_inode *ip, unsigned flags) */ if (xfs_is_reflink_inode(ip) && (flags & (IOMAP_WRITE | IOMAP_ZERO))) return true; + + /* + * Extents not yet cached requires exclusive access, don't block. + * This is an opencoded xfs_ilock_data_map_shared() to cater for the + * non-blocking behaviour. + */ + if (ip->i_d.di_format == XFS_DINODE_FMT_BTREE && + !(ip->i_df.if_flags & XFS_IFEXTENTS)) + return true; return false; } @@ -998,16 +1007,18 @@ xfs_file_iomap_begin( return xfs_file_iomap_begin_delay(inode, offset, length, iomap); } - if (need_excl_ilock(ip, flags)) { + if (need_excl_ilock(ip, flags)) lockmode = XFS_ILOCK_EXCL; - xfs_ilock(ip, XFS_ILOCK_EXCL); - } else { - lockmode = xfs_ilock_data_map_shared(ip); - } + else + lockmode = XFS_ILOCK_SHARED; - if ((flags & IOMAP_NOWAIT) && !(ip->i_df.if_flags & XFS_IFEXTENTS)) { - error = -EAGAIN; - goto out_unlock; + if (flags & IOMAP_NOWAIT) { + if (!(ip->i_df.if_flags & XFS_IFEXTENTS)) + return -EAGAIN; + if (!xfs_ilock_nowait(ip, lockmode)) + return -EAGAIN; + } else { + xfs_ilock(ip, lockmode); } ASSERT(offset <= mp->m_super->s_maxbytes); |