diff options
| -rw-r--r-- | drivers/md/dm.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/drivers/md/dm.c b/drivers/md/dm.c index a503b95ecbfb..f3cc5d99fe8d 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -639,8 +639,14 @@ static void dec_pending(struct dm_io *io, int error) * There can be just one barrier request so we use * a per-device variable for error reporting. * Note that you can't touch the bio after end_io_acct + * + * We ignore -EOPNOTSUPP for empty flush reported by + * underlying devices. We assume that if the device + * doesn't support empty barriers, it doesn't need + * cache flushing commands. */ - if (!md->barrier_error && io_error != -EOPNOTSUPP) + if (!md->barrier_error && + !(bio_empty_barrier(bio) && io_error == -EOPNOTSUPP)) md->barrier_error = io_error; end_io_acct(io); free_io(md, io); @@ -2284,7 +2290,12 @@ static void process_barrier(struct mapped_device *md, struct bio *bio) if (!bio_empty_barrier(bio)) { __split_and_process_bio(md, bio); - dm_flush(md); + /* + * If the request isn't supported, don't waste time with + * the second flush. + */ + if (md->barrier_error != -EOPNOTSUPP) + dm_flush(md); } if (md->barrier_error != DM_ENDIO_REQUEUE) |