block: get rid of bio_rw and READA
These two are confusing leftover of the old world order, combining
values of the REQ_OP_ and REQ_ namespaces. For callers that don't
special case we mostly just replace bi_rw with bio_data_dir or
op_is_write, except for the few cases where a switch over the REQ_OP_
values makes more sense. Any check for READA is replaced with an
explicit check for REQ_RAHEAD. Also remove the READA alias for
REQ_RAHEAD.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/drivers/md/dm-zero.c b/drivers/md/dm-zero.c
index 766bc93..618b875 100644
--- a/drivers/md/dm-zero.c
+++ b/drivers/md/dm-zero.c
@@ -35,16 +35,19 @@
*/
static int zero_map(struct dm_target *ti, struct bio *bio)
{
- switch(bio_rw(bio)) {
- case READ:
+ switch (bio_op(bio)) {
+ case REQ_OP_READ:
+ if (bio->bi_rw & REQ_RAHEAD) {
+ /* readahead of null bytes only wastes buffer cache */
+ return -EIO;
+ }
zero_fill_bio(bio);
break;
- case READA:
- /* readahead of null bytes only wastes buffer cache */
- return -EIO;
- case WRITE:
+ case REQ_OP_WRITE:
/* writes get silently dropped */
break;
+ default:
+ return -EIO;
}
bio_endio(bio);