From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D9163C31E45 for ; Thu, 13 Jun 2019 10:20:51 +0000 (UTC) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org [140.211.169.12]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id BA5602084D for ; Thu, 13 Jun 2019 10:20:51 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BA5602084D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=renesas.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from mail.linux-foundation.org (localhost [127.0.0.1]) by mail.linuxfoundation.org (Postfix) with ESMTP id 358801382; Thu, 13 Jun 2019 10:20:43 +0000 (UTC) Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id BD6E61306 for ; Thu, 13 Jun 2019 10:20:40 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from relmlie6.idc.renesas.com (relmlor1.renesas.com [210.160.252.171]) by smtp1.linuxfoundation.org (Postfix) with ESMTP id 3A5A963D for ; Thu, 13 Jun 2019 10:20:40 +0000 (UTC) X-IronPort-AV: E=Sophos;i="5.62,369,1554735600"; d="scan'208";a="18380808" Received: from unknown (HELO relmlir6.idc.renesas.com) ([10.200.68.152]) by relmlie6.idc.renesas.com with ESMTP; 13 Jun 2019 19:20:37 +0900 Received: from localhost.localdomain (unknown [10.166.17.210]) by relmlir6.idc.renesas.com (Postfix) with ESMTP id CE64F4274BC5; Thu, 13 Jun 2019 19:20:37 +0900 (JST) From: Yoshihiro Shimoda To: joro@8bytes.org, axboe@kernel.dk, ulf.hansson@linaro.org, wsa+renesas@sang-engineering.com Subject: [RFC PATCH v6 3/5] block: add a helper function to merge the segments by an IOMMU Date: Thu, 13 Jun 2019 19:20:13 +0900 Message-Id: <1560421215-10750-4-git-send-email-yoshihiro.shimoda.uh@renesas.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1560421215-10750-1-git-send-email-yoshihiro.shimoda.uh@renesas.com> References: <1560421215-10750-1-git-send-email-yoshihiro.shimoda.uh@renesas.com> Cc: linux-renesas-soc@vger.kernel.org, linux-mmc@vger.kernel.org, linux-block@vger.kernel.org, iommu@lists.linux-foundation.org, hch@lst.de X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: iommu-bounces@lists.linux-foundation.org Errors-To: iommu-bounces@lists.linux-foundation.org This patch adds a helper function whether a queue can merge the segments by an IOMMU. Signed-off-by: Yoshihiro Shimoda --- block/blk-settings.c | 28 ++++++++++++++++++++++++++++ include/linux/blkdev.h | 2 ++ 2 files changed, 30 insertions(+) diff --git a/block/blk-settings.c b/block/blk-settings.c index 45f2c52..4e4e13e 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -4,9 +4,11 @@ */ #include #include +#include #include #include #include +#include #include #include #include @@ -831,6 +833,32 @@ void blk_queue_write_cache(struct request_queue *q, bool wc, bool fua) } EXPORT_SYMBOL_GPL(blk_queue_write_cache); +/** + * blk_queue_can_use_iommu_merging - configure queue for merging segments. + * @q: the request queue for the device + * @dev: the device pointer for dma + * + * Tell the block layer about the iommu merging of @q. + */ +bool blk_queue_can_use_iommu_merging(struct request_queue *q, + struct device *dev) +{ + struct iommu_domain *domain; + + /* + * If the device DMA is translated by an IOMMU, we can assume + * the device can merge the segments. + */ + if (!device_iommu_mapped(dev)) + return false; + + domain = iommu_get_domain_for_dev(dev); + /* No need to update max_segment_size. see blk_queue_virt_boundary() */ + blk_queue_virt_boundary(q, iommu_get_minimum_page_size(domain) - 1); + + return true; +} + static int __init blk_settings_init(void) { blk_max_low_pfn = max_low_pfn - 1; diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 592669b..4d1f7dc 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1091,6 +1091,8 @@ extern void blk_queue_dma_alignment(struct request_queue *, int); extern void blk_queue_update_dma_alignment(struct request_queue *, int); extern void blk_queue_rq_timeout(struct request_queue *, unsigned int); extern void blk_queue_write_cache(struct request_queue *q, bool enabled, bool fua); +extern bool blk_queue_can_use_iommu_merging(struct request_queue *q, + struct device *dev); /* * Number of physical segments as sent to the device. -- 2.7.4 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu