From patchwork Tue Jun 14 17:16:02 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 9176327 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 509C260772 for ; Tue, 14 Jun 2016 17:16:31 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 436A728236 for ; Tue, 14 Jun 2016 17:16:31 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 37FC8282ED; Tue, 14 Jun 2016 17:16:31 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B8C5128047 for ; Tue, 14 Jun 2016 17:16:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752715AbcFNRQa (ORCPT ); Tue, 14 Jun 2016 13:16:30 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:60656 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752708AbcFNRQ3 (ORCPT ); Tue, 14 Jun 2016 13:16:29 -0400 Received: from [83.175.99.196] (helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.80.1 #2 (Red Hat Linux)) id 1bCrws-0005PV-CO; Tue, 14 Jun 2016 17:16:22 +0000 From: Christoph Hellwig To: axboe@kernel.dk Cc: mst@redhat.com, ooo@electrozaur.com, nab@linux-iscsi.org, linux-block@vger.kernel.org Subject: [PATCH 5/7] target: stop using blk_make_request Date: Tue, 14 Jun 2016 19:16:02 +0200 Message-Id: <1465924564-14503-6-git-send-email-hch@lst.de> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1465924564-14503-1-git-send-email-hch@lst.de> References: <1465924564-14503-1-git-send-email-hch@lst.de> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Using blk_rq_append_bio allows to append the bios to the request directly instead of having to build up a list first, and also allows to have a single code path for requests with or without data attached to them. Signed-off-by: Christoph Hellwig --- drivers/target/target_core_pscsi.c | 87 +++++++++++++++----------------------- 1 file changed, 34 insertions(+), 53 deletions(-) diff --git a/drivers/target/target_core_pscsi.c b/drivers/target/target_core_pscsi.c index 81564c8..9125d93 100644 --- a/drivers/target/target_core_pscsi.c +++ b/drivers/target/target_core_pscsi.c @@ -876,19 +876,19 @@ static inline struct bio *pscsi_get_bio(int nr_vecs) static sense_reason_t pscsi_map_sg(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents, - enum dma_data_direction data_direction, struct bio **hbio) + struct request *req) { struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev); - struct bio *bio = NULL, *tbio = NULL; + struct bio *bio = NULL; struct page *page; struct scatterlist *sg; u32 data_len = cmd->data_length, i, len, bytes, off; int nr_pages = (cmd->data_length + sgl[0].offset + PAGE_SIZE - 1) >> PAGE_SHIFT; int nr_vecs = 0, rc; - int rw = (data_direction == DMA_TO_DEVICE); + int rw = (cmd->data_direction == DMA_TO_DEVICE); - *hbio = NULL; + BUG_ON(!cmd->data_length); pr_debug("PSCSI: nr_pages: %d\n", nr_pages); @@ -927,16 +927,6 @@ pscsi_map_sg(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents, pr_debug("PSCSI: Allocated bio: %p," " dir: %s nr_vecs: %d\n", bio, (rw) ? "rw" : "r", nr_vecs); - /* - * Set *hbio pointer to handle the case: - * nr_pages > BIO_MAX_PAGES, where additional - * bios need to be added to complete a given - * command. - */ - if (!*hbio) - *hbio = tbio = bio; - else - tbio = tbio->bi_next = bio; } pr_debug("PSCSI: Calling bio_add_pc_page() i: %d" @@ -955,11 +945,16 @@ pscsi_map_sg(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents, pr_debug("PSCSI: Reached bio->bi_vcnt max:" " %d i: %d bio: %p, allocating another" " bio\n", bio->bi_vcnt, i, bio); + + rc = blk_rq_append_bio(req, bio); + if (rc) { + pr_err("pSCSI: failed to append bio\n"); + goto fail; + } + /* * Clear the pointer so that another bio will - * be allocated with pscsi_get_bio() above, the - * current bio has already been set *tbio and - * bio->bi_next. + * be allocated with pscsi_get_bio() above. */ bio = NULL; } @@ -968,13 +963,16 @@ pscsi_map_sg(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents, } } + if (bio) { + rc = blk_rq_append_bio(req, bio); + if (rc) { + pr_err("pSCSI: failed to append bio\n"); + goto fail; + } + } + return 0; fail: - while (*hbio) { - bio = *hbio; - *hbio = (*hbio)->bi_next; - bio_endio(bio); - } return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; } @@ -992,11 +990,9 @@ pscsi_execute_cmd(struct se_cmd *cmd) { struct scatterlist *sgl = cmd->t_data_sg; u32 sgl_nents = cmd->t_data_nents; - enum dma_data_direction data_direction = cmd->data_direction; struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev); struct pscsi_plugin_task *pt; struct request *req; - struct bio *hbio; sense_reason_t ret; /* @@ -1012,31 +1008,21 @@ pscsi_execute_cmd(struct se_cmd *cmd) memcpy(pt->pscsi_cdb, cmd->t_task_cdb, scsi_command_size(cmd->t_task_cdb)); - if (!sgl) { - req = blk_get_request(pdv->pdv_sd->request_queue, - (data_direction == DMA_TO_DEVICE), - GFP_KERNEL); - if (IS_ERR(req)) { - pr_err("PSCSI: blk_get_request() failed\n"); - ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; - goto fail; - } + req = blk_get_request(pdv->pdv_sd->request_queue, + (cmd->data_direction == DMA_TO_DEVICE), + GFP_KERNEL); + if (IS_ERR(req)) { + pr_err("PSCSI: blk_get_request() failed\n"); + ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; + goto fail; + } - blk_rq_set_block_pc(req); - } else { - BUG_ON(!cmd->data_length); + blk_rq_set_block_pc(req); - ret = pscsi_map_sg(cmd, sgl, sgl_nents, data_direction, &hbio); + if (sgl) { + ret = pscsi_map_sg(cmd, sgl, sgl_nents, req); if (ret) - goto fail; - - req = blk_make_request(pdv->pdv_sd->request_queue, hbio, - GFP_KERNEL); - if (IS_ERR(req)) { - pr_err("pSCSI: blk_make_request() failed\n"); - ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; - goto fail_free_bio; - } + goto fail_put_request; } req->end_io = pscsi_req_done; @@ -1057,13 +1043,8 @@ pscsi_execute_cmd(struct se_cmd *cmd) return 0; -fail_free_bio: - while (hbio) { - struct bio *bio = hbio; - hbio = hbio->bi_next; - bio_endio(bio); - } - ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; +fail_put_request: + blk_put_request(req); fail: kfree(pt); return ret;