GFS2: Add commit= mount option

It has always been possible to adjust the gfs2 log commit
interval, but only from the sysfs interface. This adds a
mount option, commit=<nn>, which will be familar to ext3
users.

The sysfs interface continues to be available as well, although
this might be removed in the future.

Also this patch cleans up some duplicated structures in the GFS2
sysfs code.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

1 files changed, 12 insertions, 1 deletions

diff --git a/fs/gfs2/ops_super.c b/fs/gfs2/ops_super.c
index 458019569dcb43..0677a837856006 100644
--- a/fs/gfs2/ops_super.c
+++ b/fs/gfs2/ops_super.c
@@ -436,8 +436,12 @@ static int gfs2_remount_fs(struct super_block *sb, int *flags, char *data)
 {
 	struct gfs2_sbd *sdp = sb->s_fs_info;
 	struct gfs2_args args = sdp->sd_args; /* Default to current settings */
+	struct gfs2_tune *gt = &sdp->sd_tune;
 	int error;
 
+	spin_lock(&gt->gt_spin);
+	args.ar_commit = gt->gt_log_flush_secs;
+	spin_unlock(&gt->gt_spin);
 	error = gfs2_mount_args(sdp, &args, data);
 	if (error)
 		return error;
@@ -473,6 +477,10 @@ static int gfs2_remount_fs(struct super_block *sb, int *flags, char *data)
 		sb->s_flags |= MS_POSIXACL;
 	else
 		sb->s_flags &= ~MS_POSIXACL;
+	spin_lock(&gt->gt_spin);
+	gt->gt_log_flush_secs = args.ar_commit;
+	spin_unlock(&gt->gt_spin);
+
 	return 0;
 }
 
@@ -550,6 +558,7 @@ static int gfs2_show_options(struct seq_file *s, struct vfsmount *mnt)
 {
 	struct gfs2_sbd *sdp = mnt->mnt_sb->s_fs_info;
 	struct gfs2_args *args = &sdp->sd_args;
+	int lfsecs;
 
 	if (is_ancestor(mnt->mnt_root, sdp->sd_master_dir))
 		seq_printf(s, ",meta");
@@ -610,7 +619,9 @@ static int gfs2_show_options(struct seq_file *s, struct vfsmount *mnt)
 	}
 	if (args->ar_discard)
 		seq_printf(s, ",discard");
-
+	lfsecs = sdp->sd_tune.gt_log_flush_secs;
+	if (lfsecs != 60)
+		seq_printf(s, ",commit=%d", lfsecs);
 	return 0;
 }