dm-verity-fec: fix corrected block count stat

dm_verity_fec::corrected seems to have been intended to count the number
of corrected blocks.  However, it actually counted the number of calls
to fec_decode_bufs() that corrected at least one error.  That's not the
same thing.  For example, in low-memory situations correcting a single
block can require many calls to fec_decode_bufs().

Fix it to count corrected blocks instead.

Fixes: ae97648e14f7 ("dm verity fec: Expose corrected block count via status")
Cc: Shubhankar Mishra <shubhankarm@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>

diff --git a/drivers/md/dm-verity-fec.c b/drivers/md/dm-verity-fec.c
index 721b7c377386e97efa671c847db809a5063bf592..1e776e0d6be5cdc00cb2c57cf05c2c0b2a6a95a2 100644 (file)
--- a/drivers/md/dm-verity-fec.c
+++ b/drivers/md/dm-verity-fec.c
@@ -163,11 +163,9 @@ error:
        if (r < 0 && neras)
                DMERR_LIMIT("%s: FEC %llu: failed to correct: %d",
                            v->data_dev->name, (unsigned long long)rsb, r);
-       else if (r > 0) {
+       else if (r > 0)
                DMWARN_LIMIT("%s: FEC %llu: corrected %d errors",
                             v->data_dev->name, (unsigned long long)rsb, r);
-               atomic64_inc(&v->fec->corrected);
-       }
 
        return r;
 }
@@ -439,6 +437,7 @@ int verity_fec_decode(struct dm_verity *v, struct dm_verity_io *io,
        }
 
        memcpy(dest, fio->output, 1 << v->data_dev_block_bits);
+       atomic64_inc(&v->fec->corrected);
 
 done:
        fio->level--;