[PATCH 20/21] xfs: add an experimental feature warning for RT data checksums

[Christoph Hellwig <hch@lst.de>]

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/xfs/xfs_message.c | 4 ++++
 fs/xfs/xfs_message.h | 1 +
 fs/xfs/xfs_mount.h   | 2 ++
 fs/xfs/xfs_rtcsum.c  | 2 +-
 4 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/fs/xfs/xfs_message.c b/fs/xfs/xfs_message.c
index 0243e509a468..53e8ed976a9b 100644
--- a/fs/xfs/xfs_message.c
+++ b/fs/xfs/xfs_message.c
@@ -149,6 +149,10 @@ xfs_warn_experimental(
 			.opstate	= XFS_OPSTATE_WARNED_LARP,
 			.name		= "logged extended attributes",
 		},
+		[XFS_EXPERIMENTAL_CSUM] = {
+			.opstate	= XFS_OPSTATE_WARNED_CSUM,
+			.name		= "data checksum",
+		},
 	};
 	ASSERT(feat >= 0 && feat < XFS_EXPERIMENTAL_MAX);
 	BUILD_BUG_ON(ARRAY_SIZE(features) != XFS_EXPERIMENTAL_MAX);
diff --git a/fs/xfs/xfs_message.h b/fs/xfs/xfs_message.h
index 811b885f41c3..d858e93e5426 100644
--- a/fs/xfs/xfs_message.h
+++ b/fs/xfs/xfs_message.h
@@ -93,6 +93,7 @@ void xfs_buf_alert_ratelimited(struct xfs_buf *bp, const char *rlmsg,
 enum xfs_experimental_feat {
 	XFS_EXPERIMENTAL_SHRINK,
 	XFS_EXPERIMENTAL_LARP,
+	XFS_EXPERIMENTAL_CSUM,
 
 	XFS_EXPERIMENTAL_MAX,
 };
diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h
index fa86697f463a..c62eb42e490a 100644
--- a/fs/xfs/xfs_mount.h
+++ b/fs/xfs/xfs_mount.h
@@ -586,6 +586,8 @@ __XFS_HAS_FEAT(nouuid, NOUUID)
  */
 #define XFS_OPSTATE_BLOCKGC_ENABLED	6
 
+/* Kernel has logged a warning about checksums */
+#define XFS_OPSTATE_WARNED_CSUM		8
 /* Kernel has logged a warning about shrink being used on this fs. */
 #define XFS_OPSTATE_WARNED_SHRINK	9
 /* Kernel has logged a warning about logged xattr updates being used. */
diff --git a/fs/xfs/xfs_rtcsum.c b/fs/xfs/xfs_rtcsum.c
index 7cdc5a5029eb..47a7b67f7412 100644
--- a/fs/xfs/xfs_rtcsum.c
+++ b/fs/xfs/xfs_rtcsum.c
@@ -310,8 +310,8 @@ xfs_rtcsum_mount(
 	}
 	mp->m_features |= XFS_FEAT_DAX_NEVER;
 
+	xfs_warn_experimental(mp, XFS_EXPERIMENTAL_CSUM);
 	xfs_info(mp, "using %s for RT device data checksums",
 		xfs_data_csum_names[mp->m_sb.sb_rtcsum_type]);
-
 	return 0;
 }
-- 
2.53.0