block: don't warn when doing fsync on read-only devices

It is possible to call fsync on a read-only handle (for example, fsck.ext2
does it when doing read-only check), and this call results in kernel
warning.

The patch b089cfd95d ("block: don't warn for flush on read-only device")
attempted to disable the warning, but it is buggy and it doesn't
(op_is_flush tests flags, but bio_op strips off the flags).

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Fixes: 721c7fc701 ("block: fail op_is_write() requests to read-only partitions")
Cc: stable@vger.kernel.org	# 4.18
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Mikulas Patocka 2018-09-05 16:14:36 -06:00 committed by Jens Axboe
parent bc811f05d7
commit 8b2ded1c94

View File

@ -2163,9 +2163,12 @@ static inline bool bio_check_ro(struct bio *bio, struct hd_struct *part)
{ {
const int op = bio_op(bio); const int op = bio_op(bio);
if (part->policy && (op_is_write(op) && !op_is_flush(op))) { if (part->policy && op_is_write(op)) {
char b[BDEVNAME_SIZE]; char b[BDEVNAME_SIZE];
if (op_is_flush(bio->bi_opf) && !bio_sectors(bio))
return false;
WARN_ONCE(1, WARN_ONCE(1,
"generic_make_request: Trying to write " "generic_make_request: Trying to write "
"to read-only block-device %s (partno %d)\n", "to read-only block-device %s (partno %d)\n",