xfs: Convert to new freezing code
Generic code now blocks all writers from standard write paths. So we add
blocking of all writers coming from ioctl (we get a protection of ioctl against
racing remount read-only as a bonus) and convert xfs_file_aio_write() to a
non-racy freeze protection. We also keep freeze protection on transaction
start to block internal filesystem writes such as removal of preallocated
blocks.
CC: Ben Myers <bpm@sgi.com>
CC: Alex Elder <elder@kernel.org>
CC: xfs@oss.sgi.com
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/xfs/xfs_trans.c b/fs/xfs/xfs_trans.c
index fdf3245..06ed520 100644
--- a/fs/xfs/xfs_trans.c
+++ b/fs/xfs/xfs_trans.c
@@ -576,8 +576,12 @@
xfs_mount_t *mp,
uint type)
{
- xfs_wait_for_freeze(mp, SB_FREEZE_TRANS);
- return _xfs_trans_alloc(mp, type, KM_SLEEP);
+ xfs_trans_t *tp;
+
+ sb_start_intwrite(mp->m_super);
+ tp = _xfs_trans_alloc(mp, type, KM_SLEEP);
+ tp->t_flags |= XFS_TRANS_FREEZE_PROT;
+ return tp;
}
xfs_trans_t *
@@ -588,6 +592,7 @@
{
xfs_trans_t *tp;
+ WARN_ON(mp->m_super->s_writers.frozen == SB_FREEZE_COMPLETE);
atomic_inc(&mp->m_active_trans);
tp = kmem_zone_zalloc(xfs_trans_zone, memflags);
@@ -611,6 +616,8 @@
xfs_extent_busy_clear(tp->t_mountp, &tp->t_busy, false);
atomic_dec(&tp->t_mountp->m_active_trans);
+ if (tp->t_flags & XFS_TRANS_FREEZE_PROT)
+ sb_end_intwrite(tp->t_mountp->m_super);
xfs_trans_free_dqinfo(tp);
kmem_zone_free(xfs_trans_zone, tp);
}
@@ -643,7 +650,11 @@
ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
ASSERT(tp->t_ticket != NULL);
- ntp->t_flags = XFS_TRANS_PERM_LOG_RES | (tp->t_flags & XFS_TRANS_RESERVE);
+ ntp->t_flags = XFS_TRANS_PERM_LOG_RES |
+ (tp->t_flags & XFS_TRANS_RESERVE) |
+ (tp->t_flags & XFS_TRANS_FREEZE_PROT);
+ /* We gave our writer reference to the new transaction */
+ tp->t_flags &= ~XFS_TRANS_FREEZE_PROT;
ntp->t_ticket = xfs_log_ticket_get(tp->t_ticket);
ntp->t_blk_res = tp->t_blk_res - tp->t_blk_res_used;
tp->t_blk_res = tp->t_blk_res_used;