From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754053AbaIVN5N (ORCPT ); Mon, 22 Sep 2014 09:57:13 -0400 Received: from casper.infradead.org ([85.118.1.10]:54542 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753879AbaIVN5M (ORCPT ); Mon, 22 Sep 2014 09:57:12 -0400 From: Christoph Hellwig To: Jens Axboe Cc: linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org Subject: [PATCH 2/2] scsi: move blk_mq_start_request call earlier Date: Mon, 22 Sep 2014 15:59:31 +0200 Message-Id: <1411394371-16254-3-git-send-email-hch@lst.de> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1411394371-16254-1-git-send-email-hch@lst.de> References: <1411394371-16254-1-git-send-email-hch@lst.de> X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Some ATA drivers need the dma drain size workaround, and thus need to call blk_mq_start_request before the S/G mapping. Signed-off-by: Christoph Hellwig --- drivers/scsi/scsi_lib.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index dc01ab2..56cc4b4 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -1846,6 +1846,8 @@ static int scsi_mq_prep_fn(struct request *req) next_rq->special = bidi_sdb; } + blk_mq_start_request(req); + return scsi_setup_cmnd(sdev, req); } @@ -1880,17 +1882,19 @@ static int scsi_queue_rq(struct blk_mq_hw_ctx *hctx, struct request *req, if (!scsi_host_queue_ready(q, shost, sdev)) goto out_dec_target_busy; + if (!(req->cmd_flags & REQ_DONTPREP)) { ret = prep_to_mq(scsi_mq_prep_fn(req)); if (ret) goto out_dec_host_busy; req->cmd_flags |= REQ_DONTPREP; + } else { + blk_mq_start_request(req); } scsi_init_cmd_errh(cmd); cmd->scsi_done = scsi_mq_done; - blk_mq_start_request(req); reason = scsi_dispatch_cmd(cmd); if (reason) { scsi_set_blocked(cmd, reason); -- 1.9.1