1 files changed, 20 insertions, 0 deletions

diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c
index 6afaaeb2950..c207fef6770 100644
--- a/fs/xfs/xfs_mount.c
+++ b/fs/xfs/xfs_mount.c
@@ -2052,6 +2052,26 @@ xfs_mount_log_sb(
         return error;
 }
 
+/*
+ * If the underlying (data/log/rt) device is readonly, there are some
+ * operations that cannot proceed.
+ */
+int
+xfs_dev_is_read_only(
+        struct xfs_mount        *mp,
+        char                    *message)
+{
+        if (xfs_readonly_buftarg(mp->m_ddev_targp) ||
+            xfs_readonly_buftarg(mp->m_logdev_targp) ||
+            (mp->m_rtdev_targp && xfs_readonly_buftarg(mp->m_rtdev_targp))) {
+                cmn_err(CE_NOTE,
+                        "XFS: %s required on read-only device.", message);
+                cmn_err(CE_NOTE,
+                        "XFS: write access unavailable, cannot proceed.");
+                return EROFS;
+        }
+        return 0;
+}
 
 #ifdef HAVE_PERCPU_SB
 /*