From 2c0468e054c0adb660ac055fc396622ec7235df9 Mon Sep 17 00:00:00 2001
From: Akilesh Kailash <akailash@google.com>
Date: Mon, 13 Sep 2021 09:26:42 +0000
Subject: [PATCH] dm verity: skip redundant verity_handle_err() on I/O errors
Git-commit: 2c0468e054c0adb660ac055fc396622ec7235df9
Patch-mainline: v5.15-rc6
References: jsc#PED-2765

Without FEC, dm-verity won't call verity_handle_err() when I/O fails,
but with FEC enabled, it currently does even if an I/O error has
occurred.

If there is an I/O error and FEC correction fails, return the error
instead of calling verity_handle_err() again.

Suggested-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Akilesh Kailash <akailash@google.com>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Coly Li <colyli@suse.de>

---
 drivers/md/dm-verity-target.c | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/drivers/md/dm-verity-target.c b/drivers/md/dm-verity-target.c
index 22a5ac82446a..88288c8d6bc8 100644
--- a/drivers/md/dm-verity-target.c
+++ b/drivers/md/dm-verity-target.c
@@ -475,6 +475,7 @@ static int verity_verify_io(struct dm_verity_io *io)
 	struct bvec_iter start;
 	unsigned b;
 	struct crypto_wait wait;
+	struct bio *bio = dm_bio_from_per_bio_data(io, v->ti->per_io_data_size);
 
 	for (b = 0; b < io->n_blocks; b++) {
 		int r;
@@ -529,9 +530,17 @@ static int verity_verify_io(struct dm_verity_io *io)
 		else if (verity_fec_decode(v, io, DM_VERITY_BLOCK_TYPE_DATA,
 					   cur_block, NULL, &start) == 0)
 			continue;
-		else if (verity_handle_err(v, DM_VERITY_BLOCK_TYPE_DATA,
-					   cur_block))
-			return -EIO;
+		else {
+			if (bio->bi_status) {
+				/*
+				 * Error correction failed; Just return error
+				 */
+				return -EIO;
+			}
+			if (verity_handle_err(v, DM_VERITY_BLOCK_TYPE_DATA,
+					      cur_block))
+				return -EIO;
+		}
 	}
 
 	return 0;
-- 
2.35.3