[PATCH v5 08/15] dm-verity: move data hash mismatch handling into its own function

Eric Biggers
2024-06-11T03:49:14Z

Move the code that handles mismatches of data block hashes into its own
function so that it doesn't clutter up verity_verify_io().

Signed-off-by: Eric Biggers <ebiggers@google.com>
---
drivers/md/dm-verity-target.c | 64 ++++++++++++++++++++---------------
1 file changed, 36 insertions(+), 28 deletions(-)

diff --git a/drivers/md/dm-verity-target.c b/drivers/md/dm-verity-target.c
index 88d2a49dca43..796d85526696 100644
--- a/drivers/md/dm-verity-target.c
+++ b/drivers/md/dm-verity-target.c
@@ -540,10 +540,42 @@ static noinline int verity_recheck(struct dm_verity *v, struct dm_verity_io *io,
mempool_free(page, &v->recheck_pool);

return r;
}

+static int verity_handle_data_hash_mismatch(struct dm_verity *v,
+ struct dm_verity_io *io,
+ struct bio *bio, sector_t blkno,
+ struct bvec_iter *start)
+{
+ if (static_branch_unlikely(&use_bh_wq_enabled) && io->in_bh) {
+ /*
+ * Error handling code (FEC included) cannot be run in the
+ * BH workqueue, so fallback to a standard workqueue.
+ */
+ return -EAGAIN;
+ }
+ if (verity_recheck(v, io, *start, blkno) == 0) {
+ if (v->validated_blocks)
+ set_bit(blkno, v->validated_blocks);
+ return 0;
+ }
+#if defined(CONFIG_DM_VERITY_FEC)
+ if (verity_fec_decode(v, io, DM_VERITY_BLOCK_TYPE_DATA, blkno,
+ NULL, start) == 0)
+ return 0;
+#endif
+ if (bio->bi_status)
+ return -EIO; /* Error correction failed; Just return error */
+
+ if (verity_handle_err(v, DM_VERITY_BLOCK_TYPE_DATA, blkno)) {
+ dm_audit_log_bio(DM_MSG_PREFIX, "verify-data", bio, blkno, 0);
+ return -EIO;
+ }
+ return 0;
+}
+
static int verity_bv_zero(struct dm_verity *v, struct dm_verity_io *io,
u8 *data, size_t len)
{
memset(data, 0, len);
return 0;
@@ -632,39 +664,15 @@ static int verity_verify_io(struct dm_verity_io *io)
if (likely(memcmp(verity_io_real_digest(v, io),
verity_io_want_digest(v, io), v->digest_size) == 0)) {
if (v->validated_blocks)
set_bit(cur_block, v->validated_blocks);
continue;
- } else if (static_branch_unlikely(&use_bh_wq_enabled) && io->in_bh) {
- /*
- * Error handling code (FEC included) cannot be run in a
- * tasklet since it may sleep, so fallback to work-queue.
- */
- return -EAGAIN;
- } else if (verity_recheck(v, io, start, cur_block) == 0) {
- if (v->validated_blocks)
- set_bit(cur_block, v->validated_blocks);
- continue;
-#if defined(CONFIG_DM_VERITY_FEC)
- } else if (verity_fec_decode(v, io, DM_VERITY_BLOCK_TYPE_DATA,
- cur_block, NULL, &start) == 0) {
- continue;
-#endif
- } 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)) {
- dm_audit_log_bio(DM_MSG_PREFIX, "verify-data",
- bio, cur_block, 0);
- return -EIO;
- }
}
+ r = verity_handle_data_hash_mismatch(v, io, bio, cur_block,
+ &start);
+ if (unlikely(r))
+ return r;
}

return 0;
}

--
2.45.1