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 Received: from smtp2.osuosl.org (smtp2.osuosl.org [140.211.166.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 84B07CCA482 for ; Thu, 30 Jun 2022 12:14:27 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp2.osuosl.org (Postfix) with ESMTP id F1B9340AD4; Thu, 30 Jun 2022 12:14:26 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp2.osuosl.org F1B9340AD4 X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp2.osuosl.org ([127.0.0.1]) by localhost (smtp2.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id oIVgSgzWm_b4; Thu, 30 Jun 2022 12:14:26 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [IPv6:2605:bc80:3010:104::8cd3:938]) by smtp2.osuosl.org (Postfix) with ESMTPS id ADDC340338; Thu, 30 Jun 2022 12:14:25 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp2.osuosl.org ADDC340338 Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 7B397C0021; Thu, 30 Jun 2022 12:14:25 +0000 (UTC) Received: from smtp2.osuosl.org (smtp2.osuosl.org [140.211.166.133]) by lists.linuxfoundation.org (Postfix) with ESMTP id E94E2C0011 for ; Thu, 30 Jun 2022 12:14:23 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp2.osuosl.org (Postfix) with ESMTP id C388340989 for ; Thu, 30 Jun 2022 12:14:23 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp2.osuosl.org C388340989 X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp2.osuosl.org ([127.0.0.1]) by localhost (smtp2.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id jXqwTf6Mesed for ; Thu, 30 Jun 2022 12:14:22 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.8.0 DKIM-Filter: OpenDKIM Filter v2.11.0 smtp2.osuosl.org 74FA440338 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) by smtp2.osuosl.org (Postfix) with ESMTPS id 74FA440338 for ; Thu, 30 Jun 2022 12:14:22 +0000 (UTC) Received: from fraeml713-chm.china.huawei.com (unknown [172.18.147.226]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4LYcbV5xxSz6H8WY; Thu, 30 Jun 2022 20:10:14 +0800 (CST) Received: from lhreml724-chm.china.huawei.com (10.201.108.75) by fraeml713-chm.china.huawei.com (10.206.15.32) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Thu, 30 Jun 2022 14:14:18 +0200 Received: from localhost.localdomain (10.69.192.58) by lhreml724-chm.china.huawei.com (10.201.108.75) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Thu, 30 Jun 2022 13:14:14 +0100 To: , , , , , , , Subject: [PATCH v5 0/5] DMA mapping changes for SCSI core Date: Thu, 30 Jun 2022 20:08:07 +0800 Message-ID: <1656590892-42307-1-git-send-email-john.garry@huawei.com> X-Mailer: git-send-email 2.8.1 MIME-Version: 1.0 X-Originating-IP: [10.69.192.58] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To lhreml724-chm.china.huawei.com (10.201.108.75) X-CFilter-Loop: Reflected Cc: linux-scsi@vger.kernel.org, linux-doc@vger.kernel.org, linuxarm@huawei.com, iommu@lists.linux.dev, linux-kernel@vger.kernel.org, linux-ide@vger.kernel.org, iommu@lists.linux-foundation.org X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: John Garry via iommu Reply-To: John Garry Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" As reported in [0], DMA mappings whose size exceeds the IOMMU IOVA caching limit may see a big performance hit. This series introduces a new DMA mapping API, dma_opt_mapping_size(), so that drivers may know this limit when performance is a factor in the mapping. The SCSI SAS transport code is modified only to use this limit. For now I did not want to touch other hosts as I have a concern that this change could cause a performance regression. I also added a patch for libata-scsi as it does not currently honour the shost max_sectors limit. [0] https://lore.kernel.org/linux-iommu/20210129092120.1482-1-thunder.leizhen@huawei.com/ Changes since v4: - tweak libata and other patch titles - Add Robin's tag (thanks!) - Clarify description of new DMA mapping API Changes since v3: - Apply max DMA optimial limit to SAS hosts only Note: Even though "scsi: core: Cap shost max_sectors only once when adding" is a subset of a previous patch I did not transfer the RB tags - Rebase on v5.19-rc4 John Garry (5): dma-mapping: Add dma_opt_mapping_size() dma-iommu: Add iommu_dma_opt_mapping_size() scsi: core: Cap shost max_sectors according to DMA limits only once scsi: scsi_transport_sas: Cap shost max_sectors according to DMA optimal limit ata: libata-scsi: Cap ata_device->max_sectors according to shost->max_sectors Documentation/core-api/dma-api.rst | 14 ++++++++++++++ drivers/ata/libata-scsi.c | 1 + drivers/iommu/dma-iommu.c | 6 ++++++ drivers/iommu/iova.c | 5 +++++ drivers/scsi/hosts.c | 5 +++++ drivers/scsi/scsi_lib.c | 4 ---- drivers/scsi/scsi_transport_sas.c | 6 ++++++ include/linux/dma-map-ops.h | 1 + include/linux/dma-mapping.h | 5 +++++ include/linux/iova.h | 2 ++ kernel/dma/mapping.c | 12 ++++++++++++ 11 files changed, 57 insertions(+), 4 deletions(-) -- 2.35.3 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4E9BC7B for ; Thu, 30 Jun 2022 12:14:23 +0000 (UTC) Received: from fraeml713-chm.china.huawei.com (unknown [172.18.147.226]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4LYcbV5xxSz6H8WY; Thu, 30 Jun 2022 20:10:14 +0800 (CST) Received: from lhreml724-chm.china.huawei.com (10.201.108.75) by fraeml713-chm.china.huawei.com (10.206.15.32) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Thu, 30 Jun 2022 14:14:18 +0200 Received: from localhost.localdomain (10.69.192.58) by lhreml724-chm.china.huawei.com (10.201.108.75) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Thu, 30 Jun 2022 13:14:14 +0100 From: John Garry To: , , , , , , , CC: , , , , , , , John Garry Subject: [PATCH v5 0/5] DMA mapping changes for SCSI core Date: Thu, 30 Jun 2022 20:08:07 +0800 Message-ID: <1656590892-42307-1-git-send-email-john.garry@huawei.com> X-Mailer: git-send-email 2.8.1 Precedence: bulk X-Mailing-List: iommu@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.69.192.58] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To lhreml724-chm.china.huawei.com (10.201.108.75) X-CFilter-Loop: Reflected Message-ID: <20220630120807.PrvssjcLrahMAG1dSKn3f0liODBQ22HIwJ3yFlOKMTA@z> As reported in [0], DMA mappings whose size exceeds the IOMMU IOVA caching limit may see a big performance hit. This series introduces a new DMA mapping API, dma_opt_mapping_size(), so that drivers may know this limit when performance is a factor in the mapping. The SCSI SAS transport code is modified only to use this limit. For now I did not want to touch other hosts as I have a concern that this change could cause a performance regression. I also added a patch for libata-scsi as it does not currently honour the shost max_sectors limit. [0] https://lore.kernel.org/linux-iommu/20210129092120.1482-1-thunder.leizhen@huawei.com/ Changes since v4: - tweak libata and other patch titles - Add Robin's tag (thanks!) - Clarify description of new DMA mapping API Changes since v3: - Apply max DMA optimial limit to SAS hosts only Note: Even though "scsi: core: Cap shost max_sectors only once when adding" is a subset of a previous patch I did not transfer the RB tags - Rebase on v5.19-rc4 John Garry (5): dma-mapping: Add dma_opt_mapping_size() dma-iommu: Add iommu_dma_opt_mapping_size() scsi: core: Cap shost max_sectors according to DMA limits only once scsi: scsi_transport_sas: Cap shost max_sectors according to DMA optimal limit ata: libata-scsi: Cap ata_device->max_sectors according to shost->max_sectors Documentation/core-api/dma-api.rst | 14 ++++++++++++++ drivers/ata/libata-scsi.c | 1 + drivers/iommu/dma-iommu.c | 6 ++++++ drivers/iommu/iova.c | 5 +++++ drivers/scsi/hosts.c | 5 +++++ drivers/scsi/scsi_lib.c | 4 ---- drivers/scsi/scsi_transport_sas.c | 6 ++++++ include/linux/dma-map-ops.h | 1 + include/linux/dma-mapping.h | 5 +++++ include/linux/iova.h | 2 ++ kernel/dma/mapping.c | 12 ++++++++++++ 11 files changed, 57 insertions(+), 4 deletions(-) -- 2.35.3