btrfs: use bio fields for op and flags

The bio REQ_OP and bi_rw rq_flag_bits are now always setup, so there is
no need to pass around the rq_flag_bits bits too. btrfs users should
should access the bio insead.

Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 146f02a..14b2d19 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -6053,7 +6053,7 @@
 
 static void submit_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio,
 			      struct bio *bio, u64 physical, int dev_nr,
-			      int rw, int async)
+			      int async)
 {
 	struct btrfs_device *dev = bbio->stripes[dev_nr].dev;
 
@@ -6061,15 +6061,14 @@
 	btrfs_io_bio(bio)->stripe_index = dev_nr;
 	bio->bi_end_io = btrfs_end_bio;
 	bio->bi_iter.bi_sector = physical >> 9;
-	bio->bi_rw |= rw;
 #ifdef DEBUG
 	{
 		struct rcu_string *name;
 
 		rcu_read_lock();
 		name = rcu_dereference(dev->name);
-		pr_debug("btrfs_map_bio: rw %d, sector=%llu, dev=%lu "
-			 "(%s id %llu), size=%u\n", rw,
+		pr_debug("btrfs_map_bio: rw %d 0x%x, sector=%llu, dev=%lu "
+			 "(%s id %llu), size=%u\n", bio_op(bio), bio->bi_rw,
 			 (u64)bio->bi_iter.bi_sector, (u_long)dev->bdev->bd_dev,
 			 name->str, dev->devid, bio->bi_iter.bi_size);
 		rcu_read_unlock();
@@ -6099,7 +6098,7 @@
 	}
 }
 
-int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
+int btrfs_map_bio(struct btrfs_root *root, struct bio *bio,
 		  int mirror_num, int async_submit)
 {
 	struct btrfs_device *dev;
@@ -6166,7 +6165,7 @@
 			bio = first_bio;
 
 		submit_stripe_bio(root, bbio, bio,
-				  bbio->stripes[dev_nr].physical, dev_nr, rw,
+				  bbio->stripes[dev_nr].physical, dev_nr,
 				  async_submit);
 	}
 	btrfs_bio_counter_dec(root->fs_info);