block: Change the type of the last .rw_page() argument

All .rw_page() callers pass an enum req_op value as last argument. Make
this explicit by changing the type of the last argument into enum req_op.
See also commit 3f289dcb4b ("block: make bdev_ops->rw_page() take a
REQ_OP instead of bool").

Cc: Tejun Heo <tj@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Damien Le Moal <damien.lemoal@wdc.com>
Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20220714180729.1065367-4-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>

drivers/block/brd.c

@@ -310,7 +310,7 @@ static void brd_submit_bio(struct bio *bio)
 }
 
 static int brd_rw_page(struct block_device *bdev, sector_t sector,
-		       struct page *page, unsigned int op)
+		       struct page *page, enum req_op op)
 {
 	struct brd_device *brd = bdev->bd_disk->private_data;
 	int err;

drivers/block/zram/zram_drv.c

@@ -1631,7 +1631,7 @@ static void zram_slot_free_notify(struct block_device *bdev,
 }
 
 static int zram_rw_page(struct block_device *bdev, sector_t sector,
-		       struct page *page, unsigned int op)
+		       struct page *page, enum req_op op)
 {
 	int offset, ret;
 	u32 index;

drivers/nvdimm/btt.c

@@ -1483,7 +1483,7 @@ static void btt_submit_bio(struct bio *bio)
 }
 
 static int btt_rw_page(struct block_device *bdev, sector_t sector,
-		struct page *page, unsigned int op)
+		struct page *page, enum req_op op)
 {
 	struct btt *btt = bdev->bd_disk->private_data;
 	int rc;

drivers/nvdimm/pmem.c

@@ -239,7 +239,7 @@ static void pmem_submit_bio(struct bio *bio)
 }
 
 static int pmem_rw_page(struct block_device *bdev, sector_t sector,
-		       struct page *page, unsigned int op)
+		       struct page *page, enum req_op op)
 {
 	struct pmem_device *pmem = bdev->bd_disk->private_data;
 	blk_status_t rc;

include/linux/blkdev.h

@@ -1381,7 +1381,7 @@ struct block_device_operations {
 			unsigned int flags);
 	int (*open) (struct block_device *, fmode_t);
 	void (*release) (struct gendisk *, fmode_t);
-	int (*rw_page)(struct block_device *, sector_t, struct page *, unsigned int);
+	int (*rw_page)(struct block_device *, sector_t, struct page *, enum req_op);
 	int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
 	int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
 	unsigned int (*check_events) (struct gendisk *disk,