From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Christoph Hellwig To: axboe@kernel.dk Cc: mst@redhat.com, ooo@electrozaur.com, bhalevy@primarydata.com, nab@linux-iscsi.org, linux-block@vger.kernel.org Subject: [PATCH 6/7] scsi/osd: open code blk_make_request Date: Mon, 13 Jun 2016 17:21:17 +0200 Message-Id: <1465831278-23653-7-git-send-email-hch@lst.de> In-Reply-To: <1465831278-23653-1-git-send-email-hch@lst.de> References: <1465831278-23653-1-git-send-email-hch@lst.de> List-ID: I wish the OSD code could simply use blk_rq_map_* helpers like everyone else, but the complex nature of deciding if we have DATA IN and/or DATA OUT buffers might make this impossible (at least for a mere human like me). But using blk_rq_append_bio at least allows sharing the setup code between request with or without dat a buffers, and given that this is the last user of blk_make_request it allows getting rid of that somewhat awkward interface. Signed-off-by: Christoph Hellwig --- block/blk-core.c | 57 ---------------------------------------- drivers/scsi/osd/osd_initiator.c | 25 +++++++++++------- include/linux/blkdev.h | 2 -- 3 files changed, 16 insertions(+), 68 deletions(-) diff --git a/block/blk-core.c b/block/blk-core.c index ceefa48..22b72ab 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1319,63 +1319,6 @@ struct request *blk_get_request(struct request_queue *q, int rw, gfp_t gfp_mask) EXPORT_SYMBOL(blk_get_request); /** - * blk_make_request - given a bio, allocate a corresponding struct request. - * @q: target request queue - * @bio: The bio describing the memory mappings that will be submitted for IO. - * It may be a chained-bio properly constructed by block/bio layer. - * @gfp_mask: gfp flags to be used for memory allocation - * - * blk_make_request is the parallel of generic_make_request for BLOCK_PC - * type commands. Where the struct request needs to be farther initialized by - * the caller. It is passed a &struct bio, which describes the memory info of - * the I/O transfer. - * - * The caller of blk_make_request must make sure that bi_io_vec - * are set to describe the memory buffers. That bio_data_dir() will return - * the needed direction of the request. (And all bio's in the passed bio-chain - * are properly set accordingly) - * - * If called under none-sleepable conditions, mapped bio buffers must not - * need bouncing, by calling the appropriate masked or flagged allocator, - * suitable for the target device. Otherwise the call to blk_queue_bounce will - * BUG. - * - * WARNING: When allocating/cloning a bio-chain, careful consideration should be - * given to how you allocate bios. In particular, you cannot use - * __GFP_DIRECT_RECLAIM for anything but the first bio in the chain. Otherwise - * you risk waiting for IO completion of a bio that hasn't been submitted yet, - * thus resulting in a deadlock. Alternatively bios should be allocated using - * bio_kmalloc() instead of bio_alloc(), as that avoids the mempool deadlock. - * If possible a big IO should be split into smaller parts when allocation - * fails. Partial allocation should not be an error, or you risk a live-lock. - */ -struct request *blk_make_request(struct request_queue *q, struct bio *bio, - gfp_t gfp_mask) -{ - struct request *rq = blk_get_request(q, bio_data_dir(bio), gfp_mask); - - if (IS_ERR(rq)) - return rq; - - rq->cmd_type = REQ_TYPE_BLOCK_PC; - - for_each_bio(bio) { - struct bio *bounce_bio = bio; - int ret; - - blk_queue_bounce(q, &bounce_bio); - ret = blk_rq_append_bio(rq, bounce_bio); - if (unlikely(ret)) { - blk_put_request(rq); - return ERR_PTR(ret); - } - } - - return rq; -} -EXPORT_SYMBOL(blk_make_request); - -/** * blk_requeue_request - put a request back on queue * @q: request queue where request should be inserted * @rq: request to be inserted diff --git a/drivers/scsi/osd/osd_initiator.c b/drivers/scsi/osd/osd_initiator.c index 868ae29d..95f456f 100644 --- a/drivers/scsi/osd/osd_initiator.c +++ b/drivers/scsi/osd/osd_initiator.c @@ -1558,18 +1558,25 @@ static int _osd_req_finalize_data_integrity(struct osd_request *or, static struct request *_make_request(struct request_queue *q, bool has_write, struct _osd_io_info *oii, gfp_t flags) { - if (oii->bio) - return blk_make_request(q, oii->bio, flags); - else { - struct request *req; - - req = blk_get_request(q, has_write ? WRITE : READ, flags); - if (IS_ERR(req)) - return req; + struct request *req; + struct bio *bio = oii->bio; + int ret; - req->cmd_type = REQ_TYPE_BLOCK_PC; + req = blk_get_request(q, has_write ? WRITE : READ, flags); + if (IS_ERR(req)) return req; + req->cmd_type = REQ_TYPE_BLOCK_PC; + + for_each_bio(bio) { + struct bio *bounce_bio = bio; + + blk_queue_bounce(req->q, &bounce_bio); + ret = blk_rq_append_bio(req, bounce_bio); + if (ret) + return ERR_PTR(ret); } + + return req; } static int _init_blk_request(struct osd_request *or, diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 998fbe0..8a984a7 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -787,8 +787,6 @@ extern void blk_rq_init(struct request_queue *q, struct request *rq); extern void blk_put_request(struct request *); extern void __blk_put_request(struct request_queue *, struct request *); extern struct request *blk_get_request(struct request_queue *, int, gfp_t); -extern struct request *blk_make_request(struct request_queue *, struct bio *, - gfp_t); extern void blk_requeue_request(struct request_queue *, struct request *); extern void blk_add_request_payload(struct request *rq, struct page *page, int offset, unsigned int len); -- 2.1.4