[PATCH 8/8] xfs: complain about bad file mapping records in the ondisk bmbt

["Darrick J. Wong" <djwong@xxxxxxxxxx>]

From: Darrick J. Wong <djwong@xxxxxxxxxx>

Similar to what we've just done for the other btrees, create a function
to log corrupt bmbt records and call it whenever we encounter a bad
record in the ondisk btree.

Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx>
---
 fs/xfs/libxfs/xfs_bmap.c       |   31 ++++++++++++++++++++++++++++++-
 fs/xfs/libxfs/xfs_bmap.h       |    2 ++
 fs/xfs/libxfs/xfs_inode_fork.c |    3 ++-
 3 files changed, 34 insertions(+), 2 deletions(-)


diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c
index 45dfa5a56154..d9083cbeb20e 100644
--- a/fs/xfs/libxfs/xfs_bmap.c
+++ b/fs/xfs/libxfs/xfs_bmap.c
@@ -1099,6 +1099,34 @@ struct xfs_iread_state {
 	xfs_extnum_t		loaded;
 };
 
+int
+xfs_bmap_complain_bad_rec(
+	struct xfs_inode		*ip,
+	int				whichfork,
+	xfs_failaddr_t			fa,
+	const struct xfs_bmbt_irec	*irec)
+{
+	struct xfs_mount		*mp = ip->i_mount;
+	const char			*forkname;
+
+	switch (whichfork) {
+	case XFS_DATA_FORK:	forkname = "data"; break;
+	case XFS_ATTR_FORK:	forkname = "attr"; break;
+	case XFS_COW_FORK:	forkname = "CoW"; break;
+	default:		forkname = "???"; break;
+	}
+
+	xfs_warn(mp,
+ "Bmap BTree record corruption in inode 0x%llx %s fork detected at %pS!",
+				ip->i_ino, forkname, fa);
+	xfs_warn(mp,
+		"Offset 0x%llx, start block 0x%llx, block count 0x%llx state 0x%x",
+		irec->br_startoff, irec->br_startblock, irec->br_blockcount,
+		irec->br_state);
+
+	return -EFSCORRUPTED;
+}
+
 /* Stuff every bmbt record from this block into the incore extent map. */
 static int
 xfs_iread_bmbt_block(
@@ -1141,7 +1169,8 @@ xfs_iread_bmbt_block(
 			xfs_inode_verifier_error(ip, -EFSCORRUPTED,
 					"xfs_iread_extents(2)", frp,
 					sizeof(*frp), fa);
-			return -EFSCORRUPTED;
+			return xfs_bmap_complain_bad_rec(ip, whichfork, fa,
+					&new);
 		}
 		xfs_iext_insert(ip, &ir->icur, &new,
 				xfs_bmap_fork_to_state(whichfork));
diff --git a/fs/xfs/libxfs/xfs_bmap.h b/fs/xfs/libxfs/xfs_bmap.h
index 0cd86781fcd5..7af24f2ef8a2 100644
--- a/fs/xfs/libxfs/xfs_bmap.h
+++ b/fs/xfs/libxfs/xfs_bmap.h
@@ -258,6 +258,8 @@ static inline uint32_t xfs_bmap_fork_to_state(int whichfork)
 
 xfs_failaddr_t xfs_bmap_validate_extent(struct xfs_inode *ip, int whichfork,
 		struct xfs_bmbt_irec *irec);
+int xfs_bmap_complain_bad_rec(struct xfs_inode *ip, int whichfork,
+		xfs_failaddr_t fa, const struct xfs_bmbt_irec *irec);
 
 int	xfs_bmapi_remap(struct xfs_trans *tp, struct xfs_inode *ip,
 		xfs_fileoff_t bno, xfs_filblks_t len, xfs_fsblock_t startblock,
diff --git a/fs/xfs/libxfs/xfs_inode_fork.c b/fs/xfs/libxfs/xfs_inode_fork.c
index 6b21760184d9..ff37eecec4b0 100644
--- a/fs/xfs/libxfs/xfs_inode_fork.c
+++ b/fs/xfs/libxfs/xfs_inode_fork.c
@@ -140,7 +140,8 @@ xfs_iformat_extents(
 				xfs_inode_verifier_error(ip, -EFSCORRUPTED,
 						"xfs_iformat_extents(2)",
 						dp, sizeof(*dp), fa);
-				return -EFSCORRUPTED;
+				return xfs_bmap_complain_bad_rec(ip, whichfork,
+						fa, &new);
 			}
 
 			xfs_iext_insert(ip, &icur, &new, state);