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=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_2 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 C0D9CC433ED for ; Tue, 13 Apr 2021 22:11:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8AAE461220 for ; Tue, 13 Apr 2021 22:11:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232750AbhDMWL3 convert rfc822-to-8bit (ORCPT ); Tue, 13 Apr 2021 18:11:29 -0400 Received: from mga18.intel.com ([134.134.136.126]:29024 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232719AbhDMWL2 (ORCPT ); Tue, 13 Apr 2021 18:11:28 -0400 IronPort-SDR: dH1Hq/GIZRdONMPRKsqlBE34VA9PBUeza2r1S5kEIfygpS4Co4yJDDYdLJGCadOy4PEexXQqpB kErKuDIsz5hA== X-IronPort-AV: E=McAfee;i="6200,9189,9953"; a="182021447" X-IronPort-AV: E=Sophos;i="5.82,220,1613462400"; d="scan'208";a="182021447" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Apr 2021 15:10:52 -0700 IronPort-SDR: PcrUGVrp3ypt2/I5BikVoQc8TzVWCqOtPCHopNNuzeXZ/CIyem29B9s8C6W1P1/RjJ2PT0HCWt 6g/TvFr12KCw== X-IronPort-AV: E=Sophos;i="5.82,220,1613462400"; d="scan'208";a="424438930" Received: from jacob-builder.jf.intel.com (HELO jacob-builder) ([10.7.199.155]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Apr 2021 15:10:52 -0700 Date: Tue, 13 Apr 2021 15:13:30 -0700 From: Jacob Pan To: Lu Baolu Cc: LKML , iommu@lists.linux-foundation.org, Joerg Roedel , Jean-Philippe Brucker , Yi Liu , Raj Ashok , "Tian, Kevin" , Jason Gunthorpe , Dave Jiang , wangzhou1@hisilicon.com, zhangfei.gao@linaro.org, vkoul@kernel.org, jacob.jun.pan@linux.intel.com Subject: Re: [PATCH 1/2] iommu/sva: Tighten SVA bind API with explicit flags Message-ID: <20210413151330.2fa6325c@jacob-builder> In-Reply-To: References: <1617901736-24788-1-git-send-email-jacob.jun.pan@linux.intel.com> Organization: OTC X-Mailer: Claws Mail 3.17.5 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Baolu, Thanks for the view. On Fri, 9 Apr 2021 20:24:22 +0800, Lu Baolu wrote: > Hi Jacob, > > On 2021/4/9 1:08, Jacob Pan wrote: > > The void* drvdata parameter isn't really used in iommu_sva_bind_device() > > API, the current IDXD code "borrows" the drvdata for a VT-d private flag > > for supervisor SVA usage. > > > > Supervisor/Privileged mode request is a generic feature. It should be > > promoted from the VT-d vendor driver to the generic code. > > > > This patch replaces void* drvdata with a unsigned int flags parameter > > and adjusts callers accordingly. > > > > Link: https://lore.kernel.org/linux-iommu/YFhiMLR35WWMW%2FHu@myrica/ > > Suggested-by: Jean-Philippe Brucker > > Signed-off-by: Jacob Pan > > --- > > drivers/dma/idxd/cdev.c | 2 +- > > drivers/dma/idxd/init.c | 6 +++--- > > drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c | 2 +- > > drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 4 ++-- > > drivers/iommu/intel/Kconfig | 1 + > > drivers/iommu/intel/svm.c | 18 > > ++++++------------ drivers/iommu/iommu.c | 9 > > ++++++--- drivers/misc/uacce/uacce.c | 2 +- > > include/linux/intel-iommu.h | 2 +- > > include/linux/intel-svm.h | 17 ++--------------- > > include/linux/iommu.h | 19 > > ++++++++++++++++--- 11 files changed, 40 insertions(+), 42 deletions(-) > > > > diff --git a/drivers/dma/idxd/cdev.c b/drivers/dma/idxd/cdev.c > > index 0db9b82..21ec82b 100644 > > --- a/drivers/dma/idxd/cdev.c > > +++ b/drivers/dma/idxd/cdev.c > > @@ -103,7 +103,7 @@ static int idxd_cdev_open(struct inode *inode, > > struct file *filp) filp->private_data = ctx; > > > > if (device_pasid_enabled(idxd)) { > > - sva = iommu_sva_bind_device(dev, current->mm, NULL); > > + sva = iommu_sva_bind_device(dev, current->mm, 0); > > if (IS_ERR(sva)) { > > rc = PTR_ERR(sva); > > dev_err(dev, "pasid allocation failed: %d\n", > > rc); diff --git a/drivers/dma/idxd/init.c b/drivers/dma/idxd/init.c > > index 085a0c3..cdc85f1 100644 > > --- a/drivers/dma/idxd/init.c > > +++ b/drivers/dma/idxd/init.c > > @@ -300,13 +300,13 @@ static struct idxd_device *idxd_alloc(struct > > pci_dev *pdev) > > static int idxd_enable_system_pasid(struct idxd_device *idxd) > > { > > - int flags; > > + unsigned int flags; > > unsigned int pasid; > > struct iommu_sva *sva; > > > > - flags = SVM_FLAG_SUPERVISOR_MODE; > > + flags = IOMMU_SVA_BIND_SUPERVISOR; > > With SVM_FLAG_SUPERVISOR_MODE removed, I guess > > #include > > in this file could be removed as well. yes, good point. > > > > > - sva = iommu_sva_bind_device(&idxd->pdev->dev, NULL, &flags); > > + sva = iommu_sva_bind_device(&idxd->pdev->dev, NULL, flags); > > if (IS_ERR(sva)) { > > dev_warn(&idxd->pdev->dev, > > "iommu sva bind failed: %ld\n", > > PTR_ERR(sva)); diff --git > > a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c > > b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c index > > bb251ca..23e287e 100644 --- > > a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c +++ > > b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c @@ -354,7 +354,7 @@ > > __arm_smmu_sva_bind(struct device *dev, struct mm_struct *mm) } > > struct iommu_sva * > > -arm_smmu_sva_bind(struct device *dev, struct mm_struct *mm, void > > *drvdata) +arm_smmu_sva_bind(struct device *dev, struct mm_struct *mm, > > unsigned int flags) { > > struct iommu_sva *handle; > > struct iommu_domain *domain = iommu_get_domain_for_dev(dev); > > diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h > > b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h index f985817..b971d4d > > 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h > > +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h > > @@ -711,7 +711,7 @@ bool arm_smmu_master_sva_enabled(struct > > arm_smmu_master *master); int arm_smmu_master_enable_sva(struct > > arm_smmu_master *master); int arm_smmu_master_disable_sva(struct > > arm_smmu_master *master); struct iommu_sva *arm_smmu_sva_bind(struct > > device *dev, struct mm_struct *mm, > > - void *drvdata); > > + unsigned int flags); > > void arm_smmu_sva_unbind(struct iommu_sva *handle); > > u32 arm_smmu_sva_get_pasid(struct iommu_sva *handle); > > void arm_smmu_sva_notifier_synchronize(void); > > @@ -742,7 +742,7 @@ static inline int > > arm_smmu_master_disable_sva(struct arm_smmu_master *master) } > > > > static inline struct iommu_sva * > > -arm_smmu_sva_bind(struct device *dev, struct mm_struct *mm, void > > *drvdata) +arm_smmu_sva_bind(struct device *dev, struct mm_struct *mm, > > unsigned int flags) { > > return ERR_PTR(-ENODEV); > > } > > diff --git a/drivers/iommu/intel/Kconfig b/drivers/iommu/intel/Kconfig > > index 28a3d15..5415052 100644 > > --- a/drivers/iommu/intel/Kconfig > > +++ b/drivers/iommu/intel/Kconfig > > @@ -41,6 +41,7 @@ config INTEL_IOMMU_SVM > > select PCI_PRI > > select MMU_NOTIFIER > > select IOASID > > + select IOMMU_SVA_LIB > > Why? Right, not needed. VT-d is not using iommu_sva_alloc/free_pasid() yet. I was under the wrong impression that iommu_sva_bind_device is part of the sva-lib. > > > help > > Shared Virtual Memory (SVM) provides a facility for devices > > to access DMA resources through process address space by > > diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c > > index 574a7e6..4b5f8b0 100644 > > --- a/drivers/iommu/intel/svm.c > > +++ b/drivers/iommu/intel/svm.c > > @@ -486,12 +486,9 @@ intel_svm_bind_mm(struct device *dev, unsigned int > > flags, } else > > pasid_max = 1 << 20; > > > > - /* Bind supervisor PASID shuld have mm = NULL */ > > - if (flags & SVM_FLAG_SUPERVISOR_MODE) { > > - if (!ecap_srs(iommu->ecap) || mm) { > > - pr_err("Supervisor PASID with user provided > > mm.\n"); > > - return -EINVAL; > > - } > > + if ((flags & IOMMU_SVA_BIND_SUPERVISOR) && > > !ecap_srs(iommu->ecap)) { > > + pr_err("Supervisor PASID not supported.\n"); > > + return -EINVAL; > > } > > > > if (!(flags & SVM_FLAG_PRIVATE_PASID)) { > > @@ -593,7 +590,7 @@ intel_svm_bind_mm(struct device *dev, unsigned int > > flags, ret = intel_pasid_setup_first_level(iommu, dev, > > mm ? mm->pgd : init_mm.pgd, > > svm->pasid, FLPT_DEFAULT_DID, > > - (mm ? 0 : PASID_FLAG_SUPERVISOR_MODE) | > > + (mm ? 0 : IOMMU_SVA_BIND_SUPERVISOR) | > > > > NO. PASID_FLAG_SUPERVISOR_MODE is an internal flag to tell the helper > whether the SRE bit should be set in the PASID entry. > OK, will keep them separate. > > (cpu_feature_enabled(X86_FEATURE_LA57) > > ? PASID_FLAG_FL5LP : 0)); > > spin_unlock_irqrestore(&iommu->lock, iflags); > > @@ -620,7 +617,7 @@ intel_svm_bind_mm(struct device *dev, unsigned int > > flags, ret = intel_pasid_setup_first_level(iommu, dev, > > mm ? mm->pgd : > > init_mm.pgd, svm->pasid, FLPT_DEFAULT_DID, > > - (mm ? 0 : > > PASID_FLAG_SUPERVISOR_MODE) | > > + (mm ? 0 : > > IOMMU_SVA_BIND_SUPERVISOR) | > > The same as above. > got it. > > (cpu_feature_enabled(X86_FEATURE_LA57) > > ? PASID_FLAG_FL5LP : 0)); > > spin_unlock_irqrestore(&iommu->lock, iflags); > > @@ -1059,11 +1056,10 @@ static irqreturn_t prq_event_thread(int irq, > > void *d) > > #define to_intel_svm_dev(handle) container_of(handle, struct > > intel_svm_dev, sva) struct iommu_sva * > > -intel_svm_bind(struct device *dev, struct mm_struct *mm, void *drvdata) > > +intel_svm_bind(struct device *dev, struct mm_struct *mm, unsigned int > > flags) { > > struct iommu_sva *sva = ERR_PTR(-EINVAL); > > struct intel_svm_dev *sdev = NULL; > > - unsigned int flags = 0; > > int ret; > > > > /* > > @@ -1071,8 +1067,6 @@ intel_svm_bind(struct device *dev, struct > > mm_struct *mm, void *drvdata) > > * It will require shared SVM data structures, i.e. combine > > io_mm > > * and intel_svm etc. > > */ > > - if (drvdata) > > - flags = *(unsigned int *)drvdata; > > mutex_lock(&pasid_mutex); > > ret = intel_svm_bind_mm(dev, flags, NULL, mm, &sdev); > > if (ret) > > diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c > > index d0b0a15..bf0a20f 100644 > > --- a/drivers/iommu/iommu.c > > +++ b/drivers/iommu/iommu.c > > @@ -2962,6 +2962,7 @@ EXPORT_SYMBOL_GPL(iommu_aux_get_pasid); > > * iommu_sva_bind_device() - Bind a process address space to a device > > * @dev: the device > > * @mm: the mm to bind, caller must hold a reference to it > > + * @flags: options for the bind operation > > * > > * Create a bond between device and address space, allowing the > > device to access > > * the mm using the returned PASID. If a bond already exists between > > @device and @@ -2974,7 +2975,7 @@ > > EXPORT_SYMBOL_GPL(iommu_aux_get_pasid); > > * On error, returns an ERR_PTR value. > > */ > > struct iommu_sva * > > -iommu_sva_bind_device(struct device *dev, struct mm_struct *mm, void > > *drvdata) +iommu_sva_bind_device(struct device *dev, struct mm_struct > > *mm, unsigned int flags) { > > struct iommu_group *group; > > struct iommu_sva *handle = ERR_PTR(-EINVAL); > > @@ -2987,6 +2988,9 @@ iommu_sva_bind_device(struct device *dev, struct > > mm_struct *mm, void *drvdata) if (!group) > > return ERR_PTR(-ENODEV); > > > > + /* Supervisor SVA does not need the current mm */ > > + if ((flags & IOMMU_SVA_BIND_SUPERVISOR) && mm) > > + return ERR_PTR(-EINVAL); > > /* Ensure device count and domain don't change while we're > > binding */ mutex_lock(&group->mutex); > > > > @@ -2999,8 +3003,7 @@ iommu_sva_bind_device(struct device *dev, struct > > mm_struct *mm, void *drvdata) if (iommu_group_device_count(group) != 1) > > goto out_unlock; > > > > - handle = ops->sva_bind(dev, mm, drvdata); > > - > > + handle = ops->sva_bind(dev, mm, flags); > > out_unlock: > > mutex_unlock(&group->mutex); > > iommu_group_put(group); > > diff --git a/drivers/misc/uacce/uacce.c b/drivers/misc/uacce/uacce.c > > index d07af4e..27e0e04 100644 > > --- a/drivers/misc/uacce/uacce.c > > +++ b/drivers/misc/uacce/uacce.c > > @@ -99,7 +99,7 @@ static int uacce_bind_queue(struct uacce_device > > *uacce, struct uacce_queue *q) if (!(uacce->flags & UACCE_DEV_SVA)) > > return 0; > > > > - handle = iommu_sva_bind_device(uacce->parent, current->mm, > > NULL); > > + handle = iommu_sva_bind_device(uacce->parent, current->mm, 0); > > if (IS_ERR(handle)) > > return PTR_ERR(handle); > > > > diff --git a/include/linux/intel-iommu.h b/include/linux/intel-iommu.h > > index 1bc46b8..cdff752 100644 > > --- a/include/linux/intel-iommu.h > > +++ b/include/linux/intel-iommu.h > > @@ -757,7 +757,7 @@ int intel_svm_bind_gpasid(struct iommu_domain > > *domain, struct device *dev, struct iommu_gpasid_bind_data *data); > > int intel_svm_unbind_gpasid(struct device *dev, u32 pasid); > > struct iommu_sva *intel_svm_bind(struct device *dev, struct mm_struct > > *mm, > > - void *drvdata); > > + unsigned int flags); > > void intel_svm_unbind(struct iommu_sva *handle); > > u32 intel_svm_get_pasid(struct iommu_sva *handle); > > int intel_svm_page_response(struct device *dev, struct > > iommu_fault_event *evt, diff --git a/include/linux/intel-svm.h > > b/include/linux/intel-svm.h index 39d368a..ef6b753 100644 > > --- a/include/linux/intel-svm.h > > +++ b/include/linux/intel-svm.h > > @@ -30,30 +30,17 @@ struct svm_dev_ops { > > * if there is no other way to do so. It should be used sparingly, if > > at all. */ > > #define SVM_FLAG_PRIVATE_PASID (1<<0) > > - > > -/* > > - * The SVM_FLAG_SUPERVISOR_MODE flag requests a PASID which can be > > used only > > - * for access to kernel addresses. No IOTLB flushes are automatically > > done > > - * for kernel mappings; it is valid only for access to the kernel's > > static > > - * 1:1 mapping of physical memory — not to vmalloc or even module > > mappings. > > - * A future API addition may permit the use of such ranges, by means > > of an > > - * explicit IOTLB flush call (akin to the DMA API's unmap method). > > - * > > - * It is unlikely that we will ever hook into flush_tlb_kernel_range() > > to > > - * do such IOTLB flushes automatically. > > - */ > > -#define SVM_FLAG_SUPERVISOR_MODE (1<<1) > > /* > > * The SVM_FLAG_GUEST_MODE flag is used when a PASID bind is for guest > > * processes. Compared to the host bind, the primary differences are: > > * 1. mm life cycle management > > * 2. fault reporting > > */ > > -#define SVM_FLAG_GUEST_MODE (1<<2) > > +#define SVM_FLAG_GUEST_MODE (1<<1) > > /* > > * The SVM_FLAG_GUEST_PASID flag is used when a guest has its own > > PASID space, > > * which requires guest and host PASID translation at both directions. > > */ > > -#define SVM_FLAG_GUEST_PASID (1<<3) > > +#define SVM_FLAG_GUEST_PASID (1<<2) > > > > #endif /* __INTEL_SVM_H__ */ > > diff --git a/include/linux/iommu.h b/include/linux/iommu.h > > index 5e7fe51..a3fbaa2 100644 > > --- a/include/linux/iommu.h > > +++ b/include/linux/iommu.h > > @@ -166,6 +166,19 @@ enum iommu_dev_features { > > > > #ifdef CONFIG_IOMMU_API > > > > +/* > > + * The IOMMU_SVA_BIND_SUPERVISOR flag requests a PASID which can be > > used only > > + * for access to kernel addresses. No IOTLB flushes are automatically > > done > > + * for kernel mappings; it is valid only for access to the kernel's > > static > > + * 1:1 mapping of physical memory — not to vmalloc or even module > > mappings. > > + * A future API addition may permit the use of such ranges, by means > > of an > > + * explicit IOTLB flush call (akin to the DMA API's unmap method). > > + * > > + * It is unlikely that we will ever hook into flush_tlb_kernel_range() > > to > > + * do such IOTLB flushes automatically. > > + */ > > +#define IOMMU_SVA_BIND_SUPERVISOR BIT(0) > > + > > /** > > * struct iommu_iotlb_gather - Range information for a pending IOTLB > > flush * > > @@ -287,7 +300,7 @@ struct iommu_ops { > > int (*aux_get_pasid)(struct iommu_domain *domain, struct > > device *dev); > > struct iommu_sva *(*sva_bind)(struct device *dev, struct > > mm_struct *mm, > > - void *drvdata); > > + unsigned int flags); > > void (*sva_unbind)(struct iommu_sva *handle); > > u32 (*sva_get_pasid)(struct iommu_sva *handle); > > > > @@ -640,7 +653,7 @@ int iommu_aux_get_pasid(struct iommu_domain > > *domain, struct device *dev); > > struct iommu_sva *iommu_sva_bind_device(struct device *dev, > > struct mm_struct *mm, > > - void *drvdata); > > + unsigned int flags); > > void iommu_sva_unbind_device(struct iommu_sva *handle); > > u32 iommu_sva_get_pasid(struct iommu_sva *handle); > > > > @@ -1015,7 +1028,7 @@ iommu_aux_get_pasid(struct iommu_domain *domain, > > struct device *dev) } > > > > static inline struct iommu_sva * > > -iommu_sva_bind_device(struct device *dev, struct mm_struct *mm, void > > *drvdata) +iommu_sva_bind_device(struct device *dev, struct mm_struct > > *mm, unsigned int flags) { > > return NULL; > > } > > > > Best regards, > baolu Thanks, Jacob