[PATCH 04/51] block: Change the type of req_op() and bio_op() into enum req_op

[Bart Van Assche <bvanassche@acm.org>]

Improve static type checking by changing the type of the value returned by
req_op() and bio_op() from unsigned int into enum req_op. Insert
'default: break;' in switch statements on the enum req_op type to prevent
that the compiler warns about these switch statements.

Cc: Christoph Hellwig <hch@lst.de>
Cc: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
---
 block/blk-merge.c         | 2 ++
 drivers/block/paride/pd.c | 2 ++
 drivers/md/dm.c           | 2 ++
 include/linux/blk-mq.h    | 6 ++++--
 include/linux/blk_types.h | 6 ++++--
 5 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/block/blk-merge.c b/block/blk-merge.c
index 0f5f42ebd0bb..9d96c9239219 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -405,6 +405,8 @@ unsigned int blk_recalc_rq_segments(struct request *rq)
 		return 1;
 	case REQ_OP_WRITE_ZEROES:
 		return 0;
+	default:
+		break;
 	}
 
 	rq_for_each_bvec(bv, rq, iter)
diff --git a/drivers/block/paride/pd.c b/drivers/block/paride/pd.c
index 3637c38c72f9..a186f5bf235e 100644
--- a/drivers/block/paride/pd.c
+++ b/drivers/block/paride/pd.c
@@ -501,6 +501,8 @@ static enum action do_pd_io_start(void)
 			return do_pd_read_start();
 		else
 			return do_pd_write_start();
+	default:
+		break;
 	}
 	return Fail;
 }
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 789f48e1a0e5..bed7ad573f79 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1539,6 +1539,8 @@ static blk_status_t __process_abnormal_io(struct clone_info *ci,
 	case REQ_OP_WRITE_ZEROES:
 		num_bios = ti->num_write_zeroes_bios;
 		break;
+	default:
+		break;
 	}
 
 	/*
diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index 45d69cc46dc7..9a1838bbed02 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -197,8 +197,10 @@ struct request {
 	void *end_io_data;
 };
 
-#define req_op(req) \
-	((req)->cmd_flags & REQ_OP_MASK)
+static inline enum req_op req_op(const struct request *req)
+{
+	return req->cmd_flags & REQ_OP_MASK;
+}
 
 static inline bool blk_rq_is_passthrough(struct request *rq)
 {
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
index cce8768bc00b..e66cbe377ae8 100644
--- a/include/linux/blk_types.h
+++ b/include/linux/blk_types.h
@@ -463,8 +463,10 @@ enum stat_group {
 	NR_STAT_GROUPS
 };
 
-#define bio_op(bio) \
-	((bio)->bi_opf & REQ_OP_MASK)
+static inline enum req_op bio_op(const struct bio *bio)
+{
+	return bio->bi_opf & REQ_OP_MASK;
+}
 
 /* obsolete, don't use in new code */
 static inline void bio_set_op_attrs(struct bio *bio, unsigned op,