xfs: add xfs_verifier_error()

We want to distinguish between corruption, CRC errors,
etc.  In addition, the full stack trace on verifier errors
seems less than helpful; it looks more like an oops than
corruption.

Create a new function to specifically alert the user to
verifier errors, which can differentiate between
EFSCORRUPTED and CRC mismatches.  It doesn't dump stack
unless the xfs error level is turned up high.

Define a new error message (EFSBADCRC) to clearly identify
CRC errors.  (Defined to EBADMSG, bad message)

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>

1 files changed, 25 insertions, 0 deletions

diff --git a/fs/xfs/xfs_error.c b/fs/xfs/xfs_error.c
index 9995b807d627..a8b2ecb5f436 100644
--- a/fs/xfs/xfs_error.c
+++ b/fs/xfs/xfs_error.c
@@ -178,3 +178,28 @@ xfs_corruption_error(
 	xfs_error_report(tag, level, mp, filename, linenum, ra);
 	xfs_alert(mp, "Corruption detected. Unmount and run xfs_repair");
 }
+
+/*
+ * Warnings specifically for verifier errors.  Differentiate CRC vs. invalid
+ * values, and omit the stack trace unless the error level is tuned high.
+ */
+void
+xfs_verifier_error(
+	struct xfs_buf		*bp)
+{
+	struct xfs_mount *mp = bp->b_target->bt_mount;
+
+	xfs_alert(mp, "Metadata %s detected at %pF, block 0x%llx",
+		  bp->b_error == EFSBADCRC ? "CRC error" : "corruption",
+		  __return_address, bp->b_bn);
+
+	xfs_alert(mp, "Unmount and run xfs_repair");
+
+	if (xfs_error_level >= XFS_ERRLEVEL_LOW) {
+		xfs_alert(mp, "First 64 bytes of corrupted metadata buffer:");
+		xfs_hex_dump(xfs_buf_offset(bp, 0), 64);
+	}
+
+	if (xfs_error_level >= XFS_ERRLEVEL_HIGH)
+		xfs_stack_trace();
+}