From: Darrick J. Wong <darrick.wong@oracle.com>
Date: Mon, 3 Oct 2016 16:11:52 +0000 (-0700)
Subject: xfs: recognize the reflink feature bit
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=e54b5bf9d7aeb92d92c7f5115035e6a851d0f0c5;p=linux-beck.git

xfs: recognize the reflink feature bit

Add the reflink feature flag to the set of recognized feature flags.
This enables users to write to reflink filesystems.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---

diff --git a/fs/xfs/libxfs/xfs_format.h b/fs/xfs/libxfs/xfs_format.h
index 5e04ea2aa902..f6547fc5e016 100644
--- a/fs/xfs/libxfs/xfs_format.h
+++ b/fs/xfs/libxfs/xfs_format.h
@@ -459,7 +459,8 @@ xfs_sb_has_compat_feature(
 #define XFS_SB_FEAT_RO_COMPAT_REFLINK  (1 << 2)		/* reflinked files */
 #define XFS_SB_FEAT_RO_COMPAT_ALL \
 		(XFS_SB_FEAT_RO_COMPAT_FINOBT | \
-		 XFS_SB_FEAT_RO_COMPAT_RMAPBT)
+		 XFS_SB_FEAT_RO_COMPAT_RMAPBT | \
+		 XFS_SB_FEAT_RO_COMPAT_REFLINK)
 #define XFS_SB_FEAT_RO_COMPAT_UNKNOWN	~XFS_SB_FEAT_RO_COMPAT_ALL
 static inline bool
 xfs_sb_has_ro_compat_feature(
diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index 15b9fcd16c67..72bde2811bd7 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -1614,6 +1614,9 @@ xfs_fs_fill_super(
 			"DAX unsupported by block device. Turning off DAX.");
 			mp->m_flags &= ~XFS_MOUNT_DAX;
 		}
+		if (xfs_sb_version_hasreflink(&mp->m_sb))
+			xfs_alert(mp,
+		"DAX and reflink have not been tested together!");
 	}
 
 	if (xfs_sb_version_hasrmapbt(&mp->m_sb)) {
@@ -1627,6 +1630,10 @@ xfs_fs_fill_super(
 	"EXPERIMENTAL reverse mapping btree feature enabled. Use at your own risk!");
 	}
 
+	if (xfs_sb_version_hasreflink(&mp->m_sb))
+		xfs_alert(mp,
+	"EXPERIMENTAL reflink feature enabled. Use at your own risk!");
+
 	error = xfs_mountfs(mp);
 	if (error)
 		goto out_filestream_unmount;