[XFS] Fix up noattr2 so that it will properly update the versionnum and

features2 fields.

Previously, mounting with noattr2 failed to achieve anything because
although it cleared the attr2 mount flag, it would set it again as soon as
it processed the superblock fields. The fix now has an explicit noattr2
flag and uses it later to fix up the versionnum and features2 fields.

SGI-PV: 980021
SGI-Modid: xfs-linux-melb:xfs-kern:31003a

Signed-off-by: Tim Shimmin <tes@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/fs/xfs/xfs_sb.h b/fs/xfs/xfs_sb.h
index d904efe7f871..e3204a36a222 100644
--- a/fs/xfs/xfs_sb.h
+++ b/fs/xfs/xfs_sb.h
@@ -473,6 +473,13 @@ static inline void xfs_sb_version_addattr2(xfs_sb_t *sbp)
                 ((sbp)->sb_features2 | XFS_SB_VERSION2_ATTR2BIT)));
 }
 
+static inline void xfs_sb_version_removeattr2(xfs_sb_t *sbp)
+{
+        sbp->sb_features2 &= ~XFS_SB_VERSION2_ATTR2BIT;
+        if (!sbp->sb_features2)
+                sbp->sb_versionnum &= ~XFS_SB_VERSION_MOREBITSBIT;
+}
+
 /*
  * end of superblock version macros
  */