[PATCH 1/5] block: update error message for bio_check_ro()

[Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>]

The existing code in the bio_check_ro() relies on the op_is_write().
op_is_write() checks for the last bit in the bio_op(). Now that we have
multiple REQ_OP_XXX with last bit set to 1 such as, (from blk_types.h):

	/* write sectors to the device */
	REQ_OP_WRITE		= 1,
	/* flush the volatile write cache */
	REQ_OP_DISCARD		= 3,
	/* securely erase sectors */
	REQ_OP_SECURE_ERASE	= 5,
	/* write the same sector many times */
	REQ_OP_WRITE_SAME	= 7,
	/* write the zero filled sector many times */
	REQ_OP_WRITE_ZEROES	= 9,

it is hard to understand which bio op failed in the bio_check_ro().

Modify the error message in bio_check_ro() to print correct REQ_OP_XXX
with the help of blk_op_str().

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
---
 block/blk-core.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/block/blk-core.c b/block/blk-core.c
index 5d1fc8e17dd1..47c8b9c48a57 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -786,9 +786,9 @@ static inline bool bio_check_ro(struct bio *bio, struct hd_struct *part)
 			return false;
 
 		WARN_ONCE(1,
-		       "generic_make_request: Trying to write "
-			"to read-only block-device %s (partno %d)\n",
-			bio_devname(bio, b), part->partno);
+			"generic_make_request: Trying op %s on the "
+			"read-only block-device %s (partno %d)\n",
+			blk_op_str(op), bio_devname(bio, b), part->partno);
 		/* Older lvm-tools actually trigger this */
 		return false;
 	}
-- 
2.21.0