From patchwork Thu Mar 16 17:00:16 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Robin Murphy X-Patchwork-Id: 9629021 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 95F5860244 for ; Thu, 16 Mar 2017 17:00:33 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 843EB2856B for ; Thu, 16 Mar 2017 17:00:33 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 788AF285B7; Thu, 16 Mar 2017 17:00:33 +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=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham 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 BD0E02856B for ; Thu, 16 Mar 2017 17:00:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752570AbdCPRAb (ORCPT ); Thu, 16 Mar 2017 13:00:31 -0400 Received: from foss.arm.com ([217.140.101.70]:36700 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751663AbdCPRAa (ORCPT ); Thu, 16 Mar 2017 13:00:30 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5D3E213D5; Thu, 16 Mar 2017 10:00:29 -0700 (PDT) Received: from e110467-lin.cambridge.arm.com (e110467-lin.cambridge.arm.com [10.1.210.40]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id A60DC3F220; Thu, 16 Mar 2017 10:00:27 -0700 (PDT) From: Robin Murphy To: joro@8bytes.org Cc: iommu@lists.linux-foundation.org, linux-arm-kernel@lists.infradead.org, will.deacon@arm.com, eric.auger@redhat.com, gabriele.paoloni@huawei.com, john.garry@huawei.com, shameerali.kolothum.thodi@huawei.com, Alex Williamson , David Woodhouse , kvm@vger.kernel.org Subject: [PATCH v2 1/4] iommu: Disambiguate MSI region types Date: Thu, 16 Mar 2017 17:00:16 +0000 Message-Id: X-Mailer: git-send-email 2.11.0.dirty In-Reply-To: References: Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The introduction of reserved regions has left a couple of rough edges which we could do with sorting out sooner rather than later. Since we are not yet addressing the potential dynamic aspect of software-managed reservations and presenting them at arbitrary fixed addresses, it is incongruous that we end up displaying hardware vs. software-managed MSI regions to userspace differently, especially since ARM-based systems may actually require one or the other, or even potentially both at once, (which iommu-dma currently has no hope of dealing with at all). Let's resolve the former user-visible inconsistency ASAP before the ABI has been baked into a kernel release, in a way that also lays the groundwork for the latter shortcoming to be addressed by follow-up patches. For clarity, rename the software-managed type to IOMMU_RESV_SW_MSI, use IOMMU_RESV_MSI to describe the hardware type, and document everything a little bit. Since the x86 MSI remapping hardware falls squarely under this meaning of IOMMU_RESV_MSI, apply that type to their regions as well, so that we tell the same story to userspace across all platforms. Secondly, as the various region types require quite different handling, and it really makes little sense to ever try combining them, convert the bitfield-esque #defines to a plain enum in the process before anyone gets the wrong impression. Fixes: d30ddcaa7b02 ("iommu: Add a new type field in iommu_resv_region") Reviewed-by: Eric Auger CC: Alex Williamson CC: David Woodhouse CC: kvm@vger.kernel.org Signed-off-by: Robin Murphy --- Notes: v2: - Reword commit message - Convert type to an enum [Eric] - Rename vfio_iommu_has_resv_msi() for clarity [Eric] drivers/iommu/amd_iommu.c | 2 +- drivers/iommu/arm-smmu-v3.c | 2 +- drivers/iommu/arm-smmu.c | 2 +- drivers/iommu/intel-iommu.c | 2 +- drivers/iommu/iommu.c | 5 +++-- drivers/vfio/vfio_iommu_type1.c | 7 +++---- include/linux/iommu.h | 18 +++++++++++++----- 7 files changed, 23 insertions(+), 15 deletions(-) diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c index 98940d1392cb..b17536d6e69b 100644 --- a/drivers/iommu/amd_iommu.c +++ b/drivers/iommu/amd_iommu.c @@ -3202,7 +3202,7 @@ static void amd_iommu_get_resv_regions(struct device *dev, region = iommu_alloc_resv_region(MSI_RANGE_START, MSI_RANGE_END - MSI_RANGE_START + 1, - 0, IOMMU_RESV_RESERVED); + 0, IOMMU_RESV_MSI); if (!region) return; list_add_tail(®ion->list, head); diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c index 5806a6acc94e..591bb96047c9 100644 --- a/drivers/iommu/arm-smmu-v3.c +++ b/drivers/iommu/arm-smmu-v3.c @@ -1888,7 +1888,7 @@ static void arm_smmu_get_resv_regions(struct device *dev, int prot = IOMMU_WRITE | IOMMU_NOEXEC | IOMMU_MMIO; region = iommu_alloc_resv_region(MSI_IOVA_BASE, MSI_IOVA_LENGTH, - prot, IOMMU_RESV_MSI); + prot, IOMMU_RESV_SW_MSI); if (!region) return; diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c index abf6496843a6..b493c99e17f7 100644 --- a/drivers/iommu/arm-smmu.c +++ b/drivers/iommu/arm-smmu.c @@ -1608,7 +1608,7 @@ static void arm_smmu_get_resv_regions(struct device *dev, int prot = IOMMU_WRITE | IOMMU_NOEXEC | IOMMU_MMIO; region = iommu_alloc_resv_region(MSI_IOVA_BASE, MSI_IOVA_LENGTH, - prot, IOMMU_RESV_MSI); + prot, IOMMU_RESV_SW_MSI); if (!region) return; diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index 238ad3447712..f1611fd6f5b0 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -5249,7 +5249,7 @@ static void intel_iommu_get_resv_regions(struct device *device, reg = iommu_alloc_resv_region(IOAPIC_RANGE_START, IOAPIC_RANGE_END - IOAPIC_RANGE_START + 1, - 0, IOMMU_RESV_RESERVED); + 0, IOMMU_RESV_MSI); if (!reg) return; list_add_tail(®->list, head); diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 8ea14f41a979..3b67144dead2 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -72,6 +72,7 @@ static const char * const iommu_group_resv_type_string[] = { [IOMMU_RESV_DIRECT] = "direct", [IOMMU_RESV_RESERVED] = "reserved", [IOMMU_RESV_MSI] = "msi", + [IOMMU_RESV_SW_MSI] = "msi", }; #define IOMMU_GROUP_ATTR(_name, _mode, _show, _store) \ @@ -1743,8 +1744,8 @@ void iommu_put_resv_regions(struct device *dev, struct list_head *list) } struct iommu_resv_region *iommu_alloc_resv_region(phys_addr_t start, - size_t length, - int prot, int type) + size_t length, int prot, + enum iommu_resv_type type) { struct iommu_resv_region *region; diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index c26fa1f3ed86..32d2633092a3 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -1182,8 +1182,7 @@ static struct vfio_group *find_iommu_group(struct vfio_domain *domain, return NULL; } -static bool vfio_iommu_has_resv_msi(struct iommu_group *group, - phys_addr_t *base) +static bool vfio_iommu_has_sw_msi(struct iommu_group *group, phys_addr_t *base) { struct list_head group_resv_regions; struct iommu_resv_region *region, *next; @@ -1192,7 +1191,7 @@ static bool vfio_iommu_has_resv_msi(struct iommu_group *group, INIT_LIST_HEAD(&group_resv_regions); iommu_get_group_resv_regions(group, &group_resv_regions); list_for_each_entry(region, &group_resv_regions, list) { - if (region->type & IOMMU_RESV_MSI) { + if (region->type == IOMMU_RESV_SW_MSI) { *base = region->start; ret = true; goto out; @@ -1283,7 +1282,7 @@ static int vfio_iommu_type1_attach_group(void *iommu_data, if (ret) goto out_domain; - resv_msi = vfio_iommu_has_resv_msi(iommu_group, &resv_msi_base); + resv_msi = vfio_iommu_has_sw_msi(iommu_group, &resv_msi_base); INIT_LIST_HEAD(&domain->group_list); list_add(&group->next, &domain->group_list); diff --git a/include/linux/iommu.h b/include/linux/iommu.h index 6a6de187ddc0..2e4de0deee53 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -125,9 +125,16 @@ enum iommu_attr { }; /* These are the possible reserved region types */ -#define IOMMU_RESV_DIRECT (1 << 0) -#define IOMMU_RESV_RESERVED (1 << 1) -#define IOMMU_RESV_MSI (1 << 2) +enum iommu_resv_type { + /* Memory regions which must be mapped 1:1 at all times */ + IOMMU_RESV_DIRECT, + /* Arbitrary "never map this or give it to a device" address ranges */ + IOMMU_RESV_RESERVED, + /* Hardware MSI region (untranslated) */ + IOMMU_RESV_MSI, + /* Software-managed MSI translation window */ + IOMMU_RESV_SW_MSI, +}; /** * struct iommu_resv_region - descriptor for a reserved memory region @@ -142,7 +149,7 @@ struct iommu_resv_region { phys_addr_t start; size_t length; int prot; - int type; + enum iommu_resv_type type; }; #ifdef CONFIG_IOMMU_API @@ -288,7 +295,8 @@ extern void iommu_get_resv_regions(struct device *dev, struct list_head *list); extern void iommu_put_resv_regions(struct device *dev, struct list_head *list); extern int iommu_request_dm_for_dev(struct device *dev); extern struct iommu_resv_region * -iommu_alloc_resv_region(phys_addr_t start, size_t length, int prot, int type); +iommu_alloc_resv_region(phys_addr_t start, size_t length, int prot, + enum iommu_resv_type type); extern int iommu_get_group_resv_regions(struct iommu_group *group, struct list_head *head);