xfs: Keep sb_bad_features2 consistent with sb_features2

Currently when we modify sb_features2, we store the same value also in
sb_bad_features2. However in most places we forget to mark field
sb_bad_features2 for logging and thus it can happen that a change to it
is lost. This results in an inconsistent sb_features2 and
sb_bad_features2 fields e.g. after xfstests test xfs/187.

Fix the problem by changing XFS_SB_FEATURES2 to actually mean both
sb_features2 and sb_bad_features2 fields since this is always what we
want to log. This isn't ideal because the fact that XFS_SB_FEATURES2
means two fields could cause some problem in future however the code is
hopefully less error prone that it is now.

Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>

fs/xfs/libxfs/xfs_format.h

@@ -304,8 +304,8 @@ typedef enum {
 #define XFS_SB_ICOUNT		XFS_SB_MVAL(ICOUNT)
 #define XFS_SB_IFREE		XFS_SB_MVAL(IFREE)
 #define XFS_SB_FDBLOCKS		XFS_SB_MVAL(FDBLOCKS)
-#define XFS_SB_FEATURES2	XFS_SB_MVAL(FEATURES2)
-#define XFS_SB_BAD_FEATURES2	XFS_SB_MVAL(BAD_FEATURES2)
+#define XFS_SB_FEATURES2	(XFS_SB_MVAL(FEATURES2) | \
+				 XFS_SB_MVAL(BAD_FEATURES2))
 #define XFS_SB_FEATURES_COMPAT	XFS_SB_MVAL(FEATURES_COMPAT)
 #define XFS_SB_FEATURES_RO_COMPAT XFS_SB_MVAL(FEATURES_RO_COMPAT)
 #define XFS_SB_FEATURES_INCOMPAT XFS_SB_MVAL(FEATURES_INCOMPAT)
@@ -319,9 +319,9 @@ typedef enum {
 	 XFS_SB_VERSIONNUM | XFS_SB_UQUOTINO | XFS_SB_GQUOTINO | \
 	 XFS_SB_QFLAGS | XFS_SB_SHARED_VN | XFS_SB_UNIT | XFS_SB_WIDTH | \
 	 XFS_SB_ICOUNT | XFS_SB_IFREE | XFS_SB_FDBLOCKS | XFS_SB_FEATURES2 | \
-	 XFS_SB_BAD_FEATURES2 | XFS_SB_FEATURES_COMPAT | \
-	 XFS_SB_FEATURES_RO_COMPAT | XFS_SB_FEATURES_INCOMPAT | \
-	 XFS_SB_FEATURES_LOG_INCOMPAT | XFS_SB_PQUOTINO)
+	 XFS_SB_FEATURES_COMPAT | XFS_SB_FEATURES_RO_COMPAT | \
+	 XFS_SB_FEATURES_INCOMPAT | XFS_SB_FEATURES_LOG_INCOMPAT | \
+	 XFS_SB_PQUOTINO)
 
 
 /*

fs/xfs/xfs_mount.c

@@ -678,7 +678,7 @@ xfs_mountfs(
 		xfs_warn(mp, "correcting sb_features alignment problem");
 		sbp->sb_features2 |= sbp->sb_bad_features2;
 		sbp->sb_bad_features2 = sbp->sb_features2;
-		mp->m_update_flags |= XFS_SB_FEATURES2 | XFS_SB_BAD_FEATURES2;
+		mp->m_update_flags |= XFS_SB_FEATURES2;
 
 		/*
 		 * Re-check for ATTR2 in case it was found in bad_features2
@@ -1436,8 +1436,7 @@ xfs_mount_log_sb(
 	int		error;
 
 	ASSERT(fields & (XFS_SB_UNIT | XFS_SB_WIDTH | XFS_SB_UUID |
-			 XFS_SB_FEATURES2 | XFS_SB_BAD_FEATURES2 |
-			 XFS_SB_VERSIONNUM));
+			 XFS_SB_FEATURES2 | XFS_SB_VERSIONNUM));
 
 	tp = xfs_trans_alloc(mp, XFS_TRANS_SB_UNIT);
 	error = xfs_trans_reserve(tp, &M_RES(mp)->tr_sb, 0, 0);