Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754844AbcDSRZi (ORCPT ); Tue, 19 Apr 2016 13:25:38 -0400 Received: from mail-wm0-f47.google.com ([74.125.82.47]:35197 "EHLO mail-wm0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754596AbcDSRZK (ORCPT ); Tue, 19 Apr 2016 13:25:10 -0400 From: Eric Auger To: eric.auger@st.com, eric.auger@linaro.org, robin.murphy@arm.com, alex.williamson@redhat.com, will.deacon@arm.com, joro@8bytes.org, tglx@linutronix.de, jason@lakedaemon.net, marc.zyngier@arm.com, christoffer.dall@linaro.org, linux-arm-kernel@lists.infradead.org Cc: patches@linaro.org, linux-kernel@vger.kernel.org, Bharat.Bhushan@freescale.com, pranav.sawargaonkar@gmail.com, p.fedin@samsung.com, iommu@lists.linux-foundation.org, Jean-Philippe.Brucker@arm.com, julien.grall@arm.com Subject: [PATCH v7 7/7] vfio/type1: return MSI mapping requirements with VFIO_IOMMU_GET_INFO Date: Tue, 19 Apr 2016 17:24:47 +0000 Message-Id: <1461086687-2658-8-git-send-email-eric.auger@linaro.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1461086687-2658-1-git-send-email-eric.auger@linaro.org> References: <1461086687-2658-1-git-send-email-eric.auger@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3661 Lines: 102 This patch allows the user-space to know whether MSI addresses need to be mapped in the IOMMU. The user-space uses VFIO_IOMMU_GET_INFO ioctl and IOMMU_INFO_REQUIRE_MSI_MAP gets set if they need to. The computation of the number of IOVA pages to be provided by the user space will be implemented in a separate patch using capability chains. Signed-off-by: Eric Auger --- v6 -> v7: - remove the computation of the number of IOVA pages to be provisionned. This number depends on the domain/group/device topology which can dynamically change. Let's rely instead rely on an arbitrary max depending on the system v4 -> v5: - move msi_info and ret declaration within the conditional code v3 -> v4: - replace former vfio_domains_require_msi_mapping by more complex computation of MSI mapping requirements, especially the number of pages to be provided by the user-space. - reword patch title RFC v1 -> v1: - derived from [RFC PATCH 3/6] vfio: Extend iommu-info to return MSIs automap state - renamed allow_msi_reconfig into require_msi_mapping - fixed VFIO_IOMMU_GET_INFO --- drivers/vfio/vfio_iommu_type1.c | 24 ++++++++++++++++++++++++ include/uapi/linux/vfio.h | 5 ++++- 2 files changed, 28 insertions(+), 1 deletion(-) diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index 51b1f15..a63ce6f 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -310,6 +310,27 @@ static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn) } /* + * vfio_domains_require_msi_mapping: return whether MSI doorbells must be + * iommu mapped + * + * returns true if msi mapping is requested + */ +static bool vfio_domains_require_msi_mapping(struct vfio_iommu *iommu) +{ + struct vfio_domain *d; + bool flag; + + mutex_lock(&iommu->lock); + /* All domains have same require_msi_map property, pick first */ + d = list_first_entry(&iommu->domain_list, struct vfio_domain, next); + flag = (!(iommu_domain_get_attr(d->domain, + DOMAIN_ATTR_MSI_MAPPING, NULL))); + + mutex_unlock(&iommu->lock); + + return flag; +} +/* * Attempt to pin pages. We really don't want to track all the pfns and * the iommu can only map chunks of consecutive pfns anyway, so get the * first page and all consecutive pages with the same locking. @@ -1231,6 +1252,9 @@ static long vfio_iommu_type1_ioctl(void *iommu_data, info.flags = VFIO_IOMMU_INFO_PGSIZES; + if (vfio_domains_require_msi_mapping(iommu)) + info.flags |= VFIO_IOMMU_INFO_REQUIRE_MSI_MAP; + info.iova_pgsizes = vfio_pgsize_bitmap(iommu); return copy_to_user((void __user *)arg, &info, minsz) ? diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h index 0637f35..4d9c97d 100644 --- a/include/uapi/linux/vfio.h +++ b/include/uapi/linux/vfio.h @@ -488,6 +488,7 @@ struct vfio_iommu_type1_info { __u32 argsz; __u32 flags; #define VFIO_IOMMU_INFO_PGSIZES (1 << 0) /* supported page sizes info */ +#define VFIO_IOMMU_INFO_REQUIRE_MSI_MAP (1 << 1)/* MSI must be mapped */ __u64 iova_pgsizes; /* Bitmap of supported page sizes */ }; @@ -501,7 +502,9 @@ struct vfio_iommu_type1_info { * * In case RESERVED_MSI_IOVA flag is set, the API only aims at registering an * IOVA region that will be used on some platforms to map the host MSI frames. - * In that specific case, vaddr is ignored. + * In that specific case, vaddr is ignored. The requirement for provisioning + * such reserved IOVA range can be checked by calling VFIO_IOMMU_GET_INFO and + * testing the VFIO_IOMMU_INFO_REQUIRE_MSI_MAP flag. */ struct vfio_iommu_type1_dma_map { __u32 argsz; -- 1.9.1