From 1e87901e189c8f01750d67485009fe3827c691bf Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Fri, 3 Sep 2010 11:56:17 +0200 Subject: [PATCH] block: filter flush bio's in __generic_make_request() There are a number of make_request based drivers which don't support cache flushes. Filter out flush bio's in __generic_make_request() so that they don't have to worry about them. All FLUSH/FUA requests with data are converted to regular IO requests and empty ones are completed immediately. Signed-off-by: Tejun Heo Signed-off-by: Jens Axboe --- block/blk-core.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/block/blk-core.c b/block/blk-core.c index 18455c4f618a..495bdc4a23da 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1509,6 +1509,19 @@ static inline void __generic_make_request(struct bio *bio) if (bio_check_eod(bio, nr_sectors)) goto end_io; + /* + * Filter flush bio's early so that make_request based + * drivers without flush support don't have to worry + * about them. + */ + if ((bio->bi_rw & (REQ_FLUSH | REQ_FUA)) && !q->flush_flags) { + bio->bi_rw &= ~(REQ_FLUSH | REQ_FUA); + if (!nr_sectors) { + err = 0; + goto end_io; + } + } + if ((bio->bi_rw & REQ_DISCARD) && (!blk_queue_discard(q) || ((bio->bi_rw & REQ_SECURE) && -- 2.20.1