[01/18] xfs: clean up the error handling in xfs_swap_extent_rmap

Commit Message

Darrick J. Wong April 29, 2020, 2:44 a.m. UTC

From: Darrick J. Wong <[e-mail]>

Clean up the error handling and make sure we actually bail out if
there's something not right with either file's fork mappings or we
couldn't clear all the COW extents.

Signed-off-by: Darrick J. Wong <[e-mail]>
---
 fs/xfs/xfs_bmap_util.c |   33 ++++++++++++++++++++++++---------
 1 file changed, 24 insertions(+), 9 deletions(-)

Patch

diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
index cfd6e64661ba..746bb0c8271c 100644
--- a/fs/xfs/xfs_bmap_util.c
+++ b/fs/xfs/xfs_bmap_util.c
@@ -1393,8 +1393,16 @@  xfs_swap_extent_rmap(
 				&nimaps, 0);
 		if (error)
 			goto out;
-		ASSERT(nimaps == 1);
-		ASSERT(tirec.br_startblock != DELAYSTARTBLOCK);
+		if (nimaps != 1 || tirec.br_startblock == DELAYSTARTBLOCK) {
+			/*
+			 * We should never get no mapping or a delalloc extent
+			 * since the donor file should have been flushed by the
+			 * caller.
+			 */
+			ASSERT(0);
+			error = -EINVAL;
+			goto out;
+		}
 
 		trace_xfs_swap_extent_rmap_remap(tip, &tirec);
 		ilen = tirec.br_blockcount;
@@ -1411,8 +1419,17 @@  xfs_swap_extent_rmap(
 					&nimaps, 0);
 			if (error)
 				goto out;
-			ASSERT(nimaps == 1);
-			ASSERT(tirec.br_startoff == irec.br_startoff);
+			if (nimaps != 1 ||
+			    tirec.br_startoff != irec.br_startoff) {
+				/*
+				 * We should never get no mapping or a mapping
+				 * for another offset, but bail out if that
+				 * ever does.
+				 */
+				ASSERT(0);
+				error = -EFSCORRUPTED;
+				goto out;
+			}
 			trace_xfs_swap_extent_rmap_remap_piece(ip, &irec);
 
 			/* Trim the extent. */
@@ -1451,11 +1468,9 @@  xfs_swap_extent_rmap(
 		offset_fsb += ilen;
 	}
 
-	tip->i_d.di_flags2 = tip_flags2;
-	return 0;
-
 out:
-	trace_xfs_swap_extent_rmap_error(ip, error, _RET_IP_);
+	if (error)
+		trace_xfs_swap_extent_rmap_error(ip, error, _RET_IP_);
 	tip->i_d.di_flags2 = tip_flags2;
 	return error;
 }
@@ -1657,7 +1672,7 @@  xfs_swap_extents(
 	if (xfs_inode_has_cow_data(tip)) {
 		error = xfs_reflink_cancel_cow_range(tip, 0, NULLFILEOFF, true);
 		if (error)
-			return error;
+			goto out_unlock;
 	}
 
 	/*