[RFC PATCH] block: remove bio_check_ro

[Liu Song]

From: Liu Song <liusong@xxxxxxxxxxxxxxxxx>

Partially revert make "bio_check_ro" only return false, and may generate
at most one warning print.

>From the commit log of a32e236eb9, it has been stated that it is
compatible with the old lvm tool, so there is a high probability that
this alarm will not really be noticed, so it is better to remove it
directly.

Signed-off-by: Liu Song <liusong@xxxxxxxxxxxxxxxxx>
---
 block/blk-core.c | 17 +----------------
 1 file changed, 1 insertion(+), 16 deletions(-)

diff --git a/block/blk-core.c b/block/blk-core.c
index a0d1104..811c2dc 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -487,20 +487,6 @@ static int __init fail_make_request_debugfs(void)
 late_initcall(fail_make_request_debugfs);
 #endif /* CONFIG_FAIL_MAKE_REQUEST */
 
-static inline bool bio_check_ro(struct bio *bio)
-{
-	if (op_is_write(bio_op(bio)) && bdev_read_only(bio->bi_bdev)) {
-		if (op_is_flush(bio->bi_opf) && !bio_sectors(bio))
-			return false;
-		pr_warn("Trying to write to read-only block-device %pg\n",
-			bio->bi_bdev);
-		/* Older lvm-tools actually trigger this */
-		return false;
-	}
-
-	return false;
-}
-
 static noinline int should_fail_bio(struct bio *bio)
 {
 	if (should_fail_request(bdev_whole(bio->bi_bdev), bio->bi_iter.bi_size))
@@ -722,8 +708,7 @@ void submit_bio_noacct(struct bio *bio)
 
 	if (should_fail_bio(bio))
 		goto end_io;
-	if (unlikely(bio_check_ro(bio)))
-		goto end_io;
+
 	if (!bio_flagged(bio, BIO_REMAPPED)) {
 		if (unlikely(bio_check_eod(bio)))
 			goto end_io;
-- 
1.8.3.1