gfs2: Enable rgrplvb for sb_fs_format 1802

Turn on rgrplvb by default for sb_fs_format > 1801.

Mount options still have to override this so a new args field to
differentiate between 'off' and 'not specified' is added, and the new
default is applied only when it's not specified.

Signed-off-by: Andrew Price <anprice@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

fs/gfs2/incore.h

@@ -586,6 +586,7 @@ struct gfs2_args {
 	unsigned int ar_errors:2;               /* errors=withdraw | panic */
 	unsigned int ar_nobarrier:1;            /* do not send barriers */
 	unsigned int ar_rgrplvb:1;		/* use lvbs for rgrp info */
+	unsigned int ar_got_rgrplvb:1;		/* Was the rgrplvb opt given? */
 	unsigned int ar_loccookie:1;		/* use location based readdir
 						   cookies */
 	s32 ar_commit;				/* Commit interval */

fs/gfs2/ops_fstype.c

@@ -171,7 +171,8 @@ static int gfs2_check_sb(struct gfs2_sbd *sdp, int silent)
 		return -EINVAL;
 	}
 
-	if (sb->sb_fs_format != GFS2_FORMAT_FS ||
+	if (sb->sb_fs_format < GFS2_FS_FORMAT_MIN ||
+	    sb->sb_fs_format > GFS2_FS_FORMAT_MAX ||
 	    sb->sb_multihost_format != GFS2_FORMAT_MULTI) {
 		fs_warn(sdp, "Unknown on-disk format, unable to mount\n");
 		return -EINVAL;
@@ -1032,13 +1033,14 @@ static int gfs2_lm_mount(struct gfs2_sbd *sdp, int silent)
 	}
 
 	if (lm->lm_mount == NULL) {
-		fs_info(sdp, "Now mounting FS...\n");
+		fs_info(sdp, "Now mounting FS (format %u)...\n", sdp->sd_sb.sb_fs_format);
 		complete_all(&sdp->sd_locking_init);
 		return 0;
 	}
 	ret = lm->lm_mount(sdp, table);
 	if (ret == 0)
-		fs_info(sdp, "Joined cluster. Now mounting FS...\n");
+		fs_info(sdp, "Joined cluster. Now mounting FS (format %u)...\n",
+		        sdp->sd_sb.sb_fs_format);
 	complete_all(&sdp->sd_locking_init);
 	return ret;
 }
@@ -1157,6 +1159,10 @@ static int gfs2_fill_super(struct super_block *sb, struct fs_context *fc)
 	if (error)
 		goto fail_locking;
 
+	/* Turn rgrplvb on by default if fs format is recent enough */
+	if (!sdp->sd_args.ar_got_rgrplvb && sdp->sd_sb.sb_fs_format > 1801)
+		sdp->sd_args.ar_rgrplvb = 1;
+
 	error = wait_on_journal(sdp);
 	if (error)
 		goto fail_sb;
@@ -1450,6 +1456,7 @@ static int gfs2_parse_param(struct fs_context *fc, struct fs_parameter *param)
 		break;
 	case Opt_rgrplvb:
 		args->ar_rgrplvb = result.boolean;
+		args->ar_got_rgrplvb = 1;
 		break;
 	case Opt_loccookie:
 		args->ar_loccookie = result.boolean;

fs/gfs2/super.h

@@ -11,6 +11,10 @@
 #include <linux/dcache.h>
 #include "incore.h"
 
+/* Supported fs format version range */
+#define GFS2_FS_FORMAT_MIN (1801)
+#define GFS2_FS_FORMAT_MAX (1802)
+
 extern void gfs2_lm_unmount(struct gfs2_sbd *sdp);
 
 static inline unsigned int gfs2_jindex_size(struct gfs2_sbd *sdp)