From patchwork Thu Aug 30 17:25:04 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Edwards X-Patchwork-Id: 10582415 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 44A2B17DB for ; Thu, 30 Aug 2018 17:25:45 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 28EC72C33A for ; Thu, 30 Aug 2018 17:25:45 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 1C0462C332; Thu, 30 Aug 2018 17:25:45 +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=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=unavailable 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 8F65D2C330 for ; Thu, 30 Aug 2018 17:25:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727086AbeH3V2y (ORCPT ); Thu, 30 Aug 2018 17:28:54 -0400 Received: from legacy.ddn.com ([64.47.133.206]:4587 "EHLO legacy.ddn.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726235AbeH3V2x (ORCPT ); Thu, 30 Aug 2018 17:28:53 -0400 Received: from LAX-EX-CAHT1.datadirect.datadirectnet.com (10.8.103.81) by LAX-EX-CAHT2.datadirect.datadirectnet.com (10.8.103.82) with Microsoft SMTP Server (TLS) id 14.3.389.1; Thu, 30 Aug 2018 10:25:42 -0700 Received: from psuche.datadirect.datadirectnet.com (10.48.114.36) by LAX-EX-CAHT1.datadirect.datadirectnet.com (10.8.103.81) with Microsoft SMTP Server (TLS) id 14.3.389.1; Thu, 30 Aug 2018 10:25:42 -0700 From: Greg Edwards To: , CC: "Nicholas A. Bellinger" , "Martin K. Petersen" , Mike Christie , "Greg Edwards" Subject: [PATCH v3] target/iblock: split T10 PI SGL across command bios Date: Thu, 30 Aug 2018 11:25:04 -0600 Message-ID: <20180830172504.12348-1-gedwards@ddn.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20180808193140.1463-1-gedwards@ddn.com> References: <20180808193140.1463-1-gedwards@ddn.com> MIME-Version: 1.0 X-Originating-IP: [10.48.114.36] Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP When T10 PI is enabled on a backing device for the iblock backstore, the PI SGL for the entire command is attached to the first bio only. This works fine if the command is covered by a single bio, but can result in ref tag errors in the client for the other bios in a multi-bio command, e.g. [ 47.631236] sda: ref tag error at location 2048 (rcvd 0) [ 47.637658] sda: ref tag error at location 4096 (rcvd 0) [ 47.644228] sda: ref tag error at location 6144 (rcvd 0) The command will be split into multiple bios if the number of data SG elements exceeds BIO_MAX_PAGES (see iblock_get_bio()). The bios may later be split again in the block layer on the host after iblock_submit_bios(), depending on the queue limits of the backing device. The block and SCSI layers will pass through the whole PI SGL down to the LLDD however that first bio is split up, but the LLDD may only use the portion that corresponds to the data length (depends on the LLDD, tested with scsi_debug). Split the PI SGL across the bios in the command, so each bio's bio_integrity_payload contains the protection information for the data in the bio. Use an sg_mapping_iter to keep track of where we are in PI SGL, so we know where to start with the next bio. Signed-off-by: Greg Edwards Reviewed-by: Mike Christie --- Changes from v2: * add back min(cmd->t_prot_nents, BIO_MAX_PAGES) for bio_integrity_alloc() from v1 Changes from v1: * expand commit message * use an sg_mapping_iter to track where we are in the PI SGL drivers/target/target_core_iblock.c | 54 ++++++++++++++++++++--------- 1 file changed, 37 insertions(+), 17 deletions(-) diff --git a/drivers/target/target_core_iblock.c b/drivers/target/target_core_iblock.c index ce1321a5cb7b..db78b1c808e8 100644 --- a/drivers/target/target_core_iblock.c +++ b/drivers/target/target_core_iblock.c @@ -635,14 +635,15 @@ static ssize_t iblock_show_configfs_dev_params(struct se_device *dev, char *b) } static int -iblock_alloc_bip(struct se_cmd *cmd, struct bio *bio) +iblock_alloc_bip(struct se_cmd *cmd, struct bio *bio, + struct sg_mapping_iter *miter) { struct se_device *dev = cmd->se_dev; struct blk_integrity *bi; struct bio_integrity_payload *bip; struct iblock_dev *ib_dev = IBLOCK_DEV(dev); - struct scatterlist *sg; - int i, rc; + int rc; + size_t resid, len; bi = bdev_get_integrity(ib_dev->ibd_bd); if (!bi) { @@ -650,31 +651,39 @@ iblock_alloc_bip(struct se_cmd *cmd, struct bio *bio) return -ENODEV; } - bip = bio_integrity_alloc(bio, GFP_NOIO, cmd->t_prot_nents); + bip = bio_integrity_alloc(bio, GFP_NOIO, + min_t(unsigned int, cmd->t_prot_nents, BIO_MAX_PAGES)); if (IS_ERR(bip)) { pr_err("Unable to allocate bio_integrity_payload\n"); return PTR_ERR(bip); } - bip->bip_iter.bi_size = (cmd->data_length / dev->dev_attrib.block_size) * - dev->prot_length; - bip->bip_iter.bi_sector = bio->bi_iter.bi_sector; + bip->bip_iter.bi_size = bio_integrity_bytes(bi, bio_sectors(bio)); + bip_set_seed(bip, bio->bi_iter.bi_sector); pr_debug("IBLOCK BIP Size: %u Sector: %llu\n", bip->bip_iter.bi_size, (unsigned long long)bip->bip_iter.bi_sector); - for_each_sg(cmd->t_prot_sg, sg, cmd->t_prot_nents, i) { + resid = bip->bip_iter.bi_size; + while (resid > 0 && sg_miter_next(miter)) { - rc = bio_integrity_add_page(bio, sg_page(sg), sg->length, - sg->offset); - if (rc != sg->length) { + len = min_t(size_t, miter->length, resid); + rc = bio_integrity_add_page(bio, miter->page, len, + offset_in_page(miter->addr)); + if (rc != len) { pr_err("bio_integrity_add_page() failed; %d\n", rc); + sg_miter_stop(miter); return -ENOMEM; } - pr_debug("Added bio integrity page: %p length: %d offset; %d\n", - sg_page(sg), sg->length, sg->offset); + pr_debug("Added bio integrity page: %p length: %lu offset: %lu\n", + miter->page, len, offset_in_page(miter->addr)); + + resid -= len; + if (len < miter->length) + miter->consumed -= miter->length - len; } + sg_miter_stop(miter); return 0; } @@ -686,12 +695,13 @@ iblock_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents, struct se_device *dev = cmd->se_dev; sector_t block_lba = target_to_linux_sector(dev, cmd->t_task_lba); struct iblock_req *ibr; - struct bio *bio, *bio_start; + struct bio *bio; struct bio_list list; struct scatterlist *sg; u32 sg_num = sgl_nents; unsigned bio_cnt; - int i, op, op_flags = 0; + int i, rc, op, op_flags = 0; + struct sg_mapping_iter prot_miter; if (data_direction == DMA_TO_DEVICE) { struct iblock_dev *ib_dev = IBLOCK_DEV(dev); @@ -726,13 +736,17 @@ iblock_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents, if (!bio) goto fail_free_ibr; - bio_start = bio; bio_list_init(&list); bio_list_add(&list, bio); refcount_set(&ibr->pending, 2); bio_cnt = 1; + if (cmd->prot_type && dev->dev_attrib.pi_prot_type) + sg_miter_start(&prot_miter, cmd->t_prot_sg, cmd->t_prot_nents, + op == REQ_OP_READ ? SG_MITER_FROM_SG : + SG_MITER_TO_SG); + for_each_sg(sgl, sg, sgl_nents, i) { /* * XXX: if the length the device accepts is shorter than the @@ -741,6 +755,12 @@ iblock_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents, */ while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset) != sg->length) { + if (cmd->prot_type && dev->dev_attrib.pi_prot_type) { + rc = iblock_alloc_bip(cmd, bio, &prot_miter); + if (rc) + goto fail_put_bios; + } + if (bio_cnt >= IBLOCK_MAX_BIO_PER_TASK) { iblock_submit_bios(&list); bio_cnt = 0; @@ -762,7 +782,7 @@ iblock_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents, } if (cmd->prot_type && dev->dev_attrib.pi_prot_type) { - int rc = iblock_alloc_bip(cmd, bio_start); + rc = iblock_alloc_bip(cmd, bio, &prot_miter); if (rc) goto fail_put_bios; }