From patchwork Thu Oct 6 08:45:19 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Auger X-Patchwork-Id: 9363989 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 950C6607D3 for ; Thu, 6 Oct 2016 08:48:40 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8341028E68 for ; Thu, 6 Oct 2016 08:48:40 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 7750C28E75; Thu, 6 Oct 2016 08:48:40 +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=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 6035C28E68 for ; Thu, 6 Oct 2016 08:48:39 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.85_2 #1 (Red Hat Linux)) id 1bs4Kf-0005gr-VN; Thu, 06 Oct 2016 08:47:13 +0000 Received: from mx1.redhat.com ([209.132.183.28]) by bombadil.infradead.org with esmtps (Exim 4.85_2 #1 (Red Hat Linux)) id 1bs4Jg-00058m-PR for linux-arm-kernel@lists.infradead.org; Thu, 06 Oct 2016 08:46:15 +0000 Received: from int-mx14.intmail.prod.int.phx2.redhat.com (int-mx14.intmail.prod.int.phx2.redhat.com [10.5.11.27]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id E7064C05491F; Thu, 6 Oct 2016 08:45:55 +0000 (UTC) Received: from localhost.redhat.com (vpn1-6-233.ams2.redhat.com [10.36.6.233]) by int-mx14.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u968jZtL011450; Thu, 6 Oct 2016 04:45:51 -0400 From: Eric Auger To: eric.auger@redhat.com, eric.auger.pro@gmail.com, christoffer.dall@linaro.org, marc.zyngier@arm.com, robin.murphy@arm.com, alex.williamson@redhat.com, will.deacon@arm.com, joro@8bytes.org, tglx@linutronix.de, jason@lakedaemon.net, linux-arm-kernel@lists.infradead.org Subject: [PATCH v13 03/15] iommu/dma: Allow MSI-only cookies Date: Thu, 6 Oct 2016 08:45:19 +0000 Message-Id: <1475743531-4780-4-git-send-email-eric.auger@redhat.com> In-Reply-To: <1475743531-4780-1-git-send-email-eric.auger@redhat.com> References: <1475743531-4780-1-git-send-email-eric.auger@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.27 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.32]); Thu, 06 Oct 2016 08:45:56 +0000 (UTC) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20161006_014613_055019_531502D2 X-CRM114-Status: GOOD ( 16.09 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: drjones@redhat.com, kvm@vger.kernel.org, Jean-Philippe.Brucker@arm.com, Manish.Jaggi@caviumnetworks.com, p.fedin@samsung.com, linux-kernel@vger.kernel.org, Bharat.Bhushan@freescale.com, iommu@lists.linux-foundation.org, pranav.sawargaonkar@gmail.com, yehuday@marvell.com MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP From: Robin Murphy IOMMU domain users such as VFIO face a similar problem to DMA API ops with regard to mapping MSI messages in systems where the MSI write is subject to IOMMU translation. With the relevant infrastructure now in place for managed DMA domains, it's actually really simple for other users to piggyback off that and reap the benefits without giving up their own IOVA management, and without having to reinvent their own wheel in the MSI layer. Allow such users to opt into automatic MSI remapping by dedicating a region of their IOVA space to a managed cookie. Signed-off-by: Robin Murphy Signed-off-by: Eric Auger --- v1 -> v2: - compared to Robin's version - add NULL last param to iommu_dma_init_domain - set the msi_geometry aperture - I removed if (base < U64_MAX - size) reserve_iova(iovad, iova_pfn(iovad, base + size), ULONG_MAX); don't get why we would reserve something out of the scope of the iova domain? what do I miss? --- drivers/iommu/dma-iommu.c | 40 ++++++++++++++++++++++++++++++++++++++++ include/linux/dma-iommu.h | 9 +++++++++ 2 files changed, 49 insertions(+) diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index c5ab866..11da1a0 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -716,3 +716,43 @@ void iommu_dma_map_msi_msg(int irq, struct msi_msg *msg) msg->address_lo += lower_32_bits(msi_page->iova); } } + +/** + * iommu_get_dma_msi_region_cookie - Configure a domain for MSI remapping only + * @domain: IOMMU domain to prepare + * @base: Base address of IOVA region to use as the MSI remapping aperture + * @size: Size of the desired MSI aperture + * + * Users who manage their own IOVA allocation and do not want DMA API support, + * but would still like to take advantage of automatic MSI remapping, can use + * this to initialise their own domain appropriately. + */ +int iommu_get_dma_msi_region_cookie(struct iommu_domain *domain, + dma_addr_t base, u64 size) +{ + struct iommu_dma_cookie *cookie; + struct iova_domain *iovad; + int ret; + + if (domain->type == IOMMU_DOMAIN_DMA) + return -EINVAL; + + ret = iommu_get_dma_cookie(domain); + if (ret) + return ret; + + ret = iommu_dma_init_domain(domain, base, size, NULL); + if (ret) { + iommu_put_dma_cookie(domain); + return ret; + } + + domain->msi_geometry.aperture_start = base; + domain->msi_geometry.aperture_end = base + size - 1; + + cookie = domain->iova_cookie; + iovad = &cookie->iovad; + + return 0; +} +EXPORT_SYMBOL(iommu_get_dma_msi_region_cookie); diff --git a/include/linux/dma-iommu.h b/include/linux/dma-iommu.h index 32c5890..1c55413 100644 --- a/include/linux/dma-iommu.h +++ b/include/linux/dma-iommu.h @@ -67,6 +67,9 @@ int iommu_dma_mapping_error(struct device *dev, dma_addr_t dma_addr); /* The DMA API isn't _quite_ the whole story, though... */ void iommu_dma_map_msi_msg(int irq, struct msi_msg *msg); +int iommu_get_dma_msi_region_cookie(struct iommu_domain *domain, + dma_addr_t base, u64 size); + #else struct iommu_domain; @@ -90,6 +93,12 @@ static inline void iommu_dma_map_msi_msg(int irq, struct msi_msg *msg) { } +static inline int iommu_get_dma_msi_region_cookie(struct iommu_domain *domain, + dma_addr_t base, u64 size) +{ + return -ENODEV; +} + #endif /* CONFIG_IOMMU_DMA */ #endif /* __KERNEL__ */ #endif /* __DMA_IOMMU_H */