dm flakey: error READ bios during the down_interval

When the corrupt_bio_byte feature was introduced it caused READ bios to
no longer be errored with -EIO during the down_interval.  This had to do
with the complexity of needing to submit READs if the corrupt_bio_byte
feature was used.

Fix it so READ bios are properly errored with -EIO; doing so early in
flakey_map() as long as there isn't a match for the corrupt_bio_byte
feature.

Fixes: a3998799fb4df ("dm flakey: add corrupt_bio_byte feature")
Reported-by: Akira Hayakawa <ruby.wktk@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org

1 files changed, 15 insertions, 8 deletions

diff --git a/drivers/md/dm-flakey.c b/drivers/md/dm-flakey.c
index 29b99fb6a16a..19db13e99466 100644
--- a/drivers/md/dm-flakey.c
+++ b/drivers/md/dm-flakey.c
@@ -289,10 +289,16 @@ static int flakey_map(struct dm_target *ti, struct bio *bio)
                 pb->bio_submitted = true;
 
                 /*
-                 * Map reads as normal.
+                 * Map reads as normal only if corrupt_bio_byte set.
                  */
-                if (bio_data_dir(bio) == READ)
-                        goto map_bio;
+                if (bio_data_dir(bio) == READ) {
+                        /* If flags were specified, only corrupt those that match. */
+                        if (fc->corrupt_bio_byte && (fc->corrupt_bio_rw == READ) &&
+                            all_corrupt_bio_flags_match(bio, fc))
+                                goto map_bio;
+                        else
+                                return -EIO;
+                }
 
                 /*
                  * Drop writes?
@@ -330,12 +336,13 @@ static int flakey_end_io(struct dm_target *ti, struct bio *bio, int error)
 
         /*
          * Corrupt successful READs while in down state.
-         * If flags were specified, only corrupt those that match.
          */
-        if (fc->corrupt_bio_byte && !error && pb->bio_submitted &&
-            (bio_data_dir(bio) == READ) && (fc->corrupt_bio_rw == READ) &&
-            all_corrupt_bio_flags_match(bio, fc))
-                corrupt_bio_data(bio, fc);
+        if (!error && pb->bio_submitted && (bio_data_dir(bio) == READ)) {
+                if (fc->corrupt_bio_byte)
+                        corrupt_bio_data(bio, fc);
+                else
+                        return -EIO;
+        }
 
         return error;
 }