From: Darrick J. Wong <darrick.wong@oracle.com>
Date: Fri, 26 Aug 2016 05:59:19 +0000 (+1000)
Subject: xfs: disallow mounting of realtime + rmap filesystems
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=738f57c16a2bb527c705641f0fc1c68ff8cba72a;p=linux-beck.git

xfs: disallow mounting of realtime + rmap filesystems

Since the kernel doesn't currently support the realtime rmapbt,
don't allow such filesystems to be mounted.  Support will appear
in a future release.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
---

diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index 24ef83ef04de..fd6be45b3a1e 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -1574,9 +1574,16 @@ xfs_fs_fill_super(
 		}
 	}
 
-	if (xfs_sb_version_hasrmapbt(&mp->m_sb))
+	if (xfs_sb_version_hasrmapbt(&mp->m_sb)) {
+		if (mp->m_sb.sb_rblocks) {
+			xfs_alert(mp,
+	"EXPERIMENTAL reverse mapping btree not compatible with realtime device!");
+			error = -EINVAL;
+			goto out_filestream_unmount;
+		}
 		xfs_alert(mp,
 	"EXPERIMENTAL reverse mapping btree feature enabled. Use at your own risk!");
+	}
 
 	error = xfs_mountfs(mp);
 	if (error)