xfs: kill XBF_FS_MANAGED buffers
Filesystem level managed buffers are buffers that have their
lifecycle controlled by the filesystem layer, not the buffer cache.
We currently cache these buffers, which makes cleanup and cache
walking somewhat troublesome. Convert the fs managed buffers to
uncached buffers obtained by via xfs_buf_get_uncached(), and remove
the XBF_FS_MANAGED special cases from the buffer cache.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c
index 14fc6e9..fbca293 100644
--- a/fs/xfs/xfs_mount.c
+++ b/fs/xfs/xfs_mount.c
@@ -646,7 +646,6 @@
xfs_readsb(xfs_mount_t *mp, int flags)
{
unsigned int sector_size;
- unsigned int extra_flags;
xfs_buf_t *bp;
int error;
@@ -659,28 +658,24 @@
* access to the superblock.
*/
sector_size = xfs_getsize_buftarg(mp->m_ddev_targp);
- extra_flags = XBF_LOCK | XBF_FS_MANAGED | XBF_MAPPED;
- bp = xfs_buf_read(mp->m_ddev_targp, XFS_SB_DADDR, BTOBB(sector_size),
- extra_flags);
- if (!bp || XFS_BUF_ISERROR(bp)) {
- xfs_fs_mount_cmn_err(flags, "SB read failed");
- error = bp ? XFS_BUF_GETERROR(bp) : ENOMEM;
- goto fail;
+reread:
+ bp = xfs_buf_read_uncached(mp, mp->m_ddev_targp,
+ XFS_SB_DADDR, sector_size, 0);
+ if (!bp) {
+ xfs_fs_mount_cmn_err(flags, "SB buffer read failed");
+ return EIO;
}
- ASSERT(XFS_BUF_ISBUSY(bp));
- ASSERT(XFS_BUF_VALUSEMA(bp) <= 0);
/*
* Initialize the mount structure from the superblock.
* But first do some basic consistency checking.
*/
xfs_sb_from_disk(&mp->m_sb, XFS_BUF_TO_SBP(bp));
-
error = xfs_mount_validate_sb(mp, &(mp->m_sb), flags);
if (error) {
xfs_fs_mount_cmn_err(flags, "SB validate failed");
- goto fail;
+ goto release_buf;
}
/*
@@ -691,7 +686,7 @@
"device supports only %u byte sectors (not %u)",
sector_size, mp->m_sb.sb_sectsize);
error = ENOSYS;
- goto fail;
+ goto release_buf;
}
/*
@@ -699,33 +694,20 @@
* re-read the superblock so the buffer is correctly sized.
*/
if (sector_size < mp->m_sb.sb_sectsize) {
- XFS_BUF_UNMANAGE(bp);
xfs_buf_relse(bp);
sector_size = mp->m_sb.sb_sectsize;
- bp = xfs_buf_read(mp->m_ddev_targp, XFS_SB_DADDR,
- BTOBB(sector_size), extra_flags);
- if (!bp || XFS_BUF_ISERROR(bp)) {
- xfs_fs_mount_cmn_err(flags, "SB re-read failed");
- error = bp ? XFS_BUF_GETERROR(bp) : ENOMEM;
- goto fail;
- }
- ASSERT(XFS_BUF_ISBUSY(bp));
- ASSERT(XFS_BUF_VALUSEMA(bp) <= 0);
+ goto reread;
}
/* Initialize per-cpu counters */
xfs_icsb_reinit_counters(mp);
mp->m_sb_bp = bp;
- xfs_buf_relse(bp);
- ASSERT(XFS_BUF_VALUSEMA(bp) > 0);
+ xfs_buf_unlock(bp);
return 0;
- fail:
- if (bp) {
- XFS_BUF_UNMANAGE(bp);
- xfs_buf_relse(bp);
- }
+release_buf:
+ xfs_buf_relse(bp);
return error;
}
@@ -2005,18 +1987,13 @@
*/
void
xfs_freesb(
- xfs_mount_t *mp)
+ struct xfs_mount *mp)
{
- xfs_buf_t *bp;
+ struct xfs_buf *bp = mp->m_sb_bp;
- /*
- * Use xfs_getsb() so that the buffer will be locked
- * when we call xfs_buf_relse().
- */
- bp = xfs_getsb(mp, 0);
- XFS_BUF_UNMANAGE(bp);
- xfs_buf_relse(bp);
+ xfs_buf_lock(bp);
mp->m_sb_bp = NULL;
+ xfs_buf_relse(bp);
}
/*