From a27a263bae072a499acc77b632238a6dacccf888 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 16 Jun 2011 12:02:23 +0000 Subject: xfs: make log devices with write back caches work There's no reason not to support cache flushing on external log devices. The only thing this really requires is flushing the data device first both in fsync and log commits. A side effect is that we also have to remove the barrier write test during mount, which has been superflous since the new FLUSH+FUA code anyway. Also use the chance to flush the RT subvolume write cache before the fsync commit, which is required for correct semantics. Signed-off-by: Christoph Hellwig Signed-off-by: Alex Elder --- fs/xfs/linux-2.6/xfs_super.c | 75 -------------------------------------------- 1 file changed, 75 deletions(-) (limited to 'fs/xfs/linux-2.6/xfs_super.c') diff --git a/fs/xfs/linux-2.6/xfs_super.c b/fs/xfs/linux-2.6/xfs_super.c index 1e3a7ce804d..a1a881e68a9 100644 --- a/fs/xfs/linux-2.6/xfs_super.c +++ b/fs/xfs/linux-2.6/xfs_super.c @@ -627,68 +627,6 @@ xfs_blkdev_put( blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL); } -/* - * Try to write out the superblock using barriers. - */ -STATIC int -xfs_barrier_test( - xfs_mount_t *mp) -{ - xfs_buf_t *sbp = xfs_getsb(mp, 0); - int error; - - XFS_BUF_UNDONE(sbp); - XFS_BUF_UNREAD(sbp); - XFS_BUF_UNDELAYWRITE(sbp); - XFS_BUF_WRITE(sbp); - XFS_BUF_UNASYNC(sbp); - XFS_BUF_ORDERED(sbp); - - xfsbdstrat(mp, sbp); - error = xfs_buf_iowait(sbp); - - /* - * Clear all the flags we set and possible error state in the - * buffer. We only did the write to try out whether barriers - * worked and shouldn't leave any traces in the superblock - * buffer. - */ - XFS_BUF_DONE(sbp); - XFS_BUF_ERROR(sbp, 0); - XFS_BUF_UNORDERED(sbp); - - xfs_buf_relse(sbp); - return error; -} - -STATIC void -xfs_mountfs_check_barriers(xfs_mount_t *mp) -{ - int error; - - if (mp->m_logdev_targp != mp->m_ddev_targp) { - xfs_notice(mp, - "Disabling barriers, not supported with external log device"); - mp->m_flags &= ~XFS_MOUNT_BARRIER; - return; - } - - if (xfs_readonly_buftarg(mp->m_ddev_targp)) { - xfs_notice(mp, - "Disabling barriers, underlying device is readonly"); - mp->m_flags &= ~XFS_MOUNT_BARRIER; - return; - } - - error = xfs_barrier_test(mp); - if (error) { - xfs_notice(mp, - "Disabling barriers, trial barrier write failed"); - mp->m_flags &= ~XFS_MOUNT_BARRIER; - return; - } -} - void xfs_blkdev_issue_flush( xfs_buftarg_t *buftarg) @@ -1240,14 +1178,6 @@ xfs_fs_remount( switch (token) { case Opt_barrier: mp->m_flags |= XFS_MOUNT_BARRIER; - - /* - * Test if barriers are actually working if we can, - * else delay this check until the filesystem is - * marked writeable. - */ - if (!(mp->m_flags & XFS_MOUNT_RDONLY)) - xfs_mountfs_check_barriers(mp); break; case Opt_nobarrier: mp->m_flags &= ~XFS_MOUNT_BARRIER; @@ -1282,8 +1212,6 @@ xfs_fs_remount( /* ro -> rw */ if ((mp->m_flags & XFS_MOUNT_RDONLY) && !(*flags & MS_RDONLY)) { mp->m_flags &= ~XFS_MOUNT_RDONLY; - if (mp->m_flags & XFS_MOUNT_BARRIER) - xfs_mountfs_check_barriers(mp); /* * If this is the first remount to writeable state we @@ -1465,9 +1393,6 @@ xfs_fs_fill_super( if (error) goto out_free_sb; - if (mp->m_flags & XFS_MOUNT_BARRIER) - xfs_mountfs_check_barriers(mp); - error = xfs_filestream_mount(mp); if (error) goto out_free_sb; -- cgit v1.2.3-70-g09d2