From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jean-Philippe Brucker Subject: Re: [PATCH v4 04/22] iommu: Introduce attach/detach_pasid_table API Date: Tue, 5 Mar 2019 15:23:54 +0000 Message-ID: <17894c69-7d64-b85a-be91-0755aeb08ca3@arm.com> References: <20190218135504.25048-1-eric.auger@redhat.com> <20190218135504.25048-5-eric.auger@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20190218135504.25048-5-eric.auger@redhat.com> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Eric Auger , eric.auger.pro@gmail.com, iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu, joro@8bytes.org, alex.williamson@redhat.com, jacob.jun.pan@linux.intel.com, yi.l.liu@linux.intel.com, will.deacon@arm.com, robin.murphy@arm.com Cc: marc.zyngier@arm.com, peter.maydell@linaro.org, kevin.tian@intel.com, ashok.raj@intel.com, christoffer.dall@arm.com List-Id: iommu@lists.linux-foundation.org On 18/02/2019 13:54, Eric Auger wrote: > From: Jacob Pan > > In virtualization use case, when a guest is assigned > a PCI host device, protected by a virtual IOMMU on the guest, > the physical IOMMU must be programmed to be consistent with > the guest mappings. If the physical IOMMU supports two > translation stages it makes sense to program guest mappings > onto the first stage/level (ARM/Intel terminology) while the host > owns the stage/level 2. > > In that case, it is mandated to trap on guest configuration > settings and pass those to the physical iommu driver. > > This patch adds a new API to the iommu subsystem that allows > to set/unset the pasid table information. > > A generic iommu_pasid_table_config struct is introduced in > a new iommu.h uapi header. This is going to be used by the VFIO > user API. > > Signed-off-by: Jean-Philippe Brucker > Signed-off-by: Liu, Yi L > Signed-off-by: Ashok Raj > Signed-off-by: Jacob Pan > Signed-off-by: Eric Auger > > --- > > This patch generalizes the API introduced by Jacob & co-authors in > https://lwn.net/Articles/754331/ > > v3 -> v4: > - s/set_pasid_table/attach_pasid_table > - restore detach_pasid_table. Detach can be used on unwind path. > - add padding > - remove @abort > - signature used for config and format > - add comments for fields in the SMMU struct > > v2 -> v3: > - replace unbind/bind by set_pasid_table > - move table pointer and pasid bits in the generic part of the struct > > v1 -> v2: > - restore the original pasid table name > - remove the struct device * parameter in the API > - reworked iommu_pasid_smmuv3 > --- > drivers/iommu/iommu.c | 19 +++++++++++++++ > include/linux/iommu.h | 22 ++++++++++++++++++ > include/uapi/linux/iommu.h | 47 ++++++++++++++++++++++++++++++++++++++ > 3 files changed, 88 insertions(+) > > diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c > index c297cdcf7f89..b3adb77cb14c 100644 > --- a/drivers/iommu/iommu.c > +++ b/drivers/iommu/iommu.c > @@ -1545,6 +1545,25 @@ int iommu_attach_device(struct iommu_domain *domain, struct device *dev) > } > EXPORT_SYMBOL_GPL(iommu_attach_device); > > +int iommu_attach_pasid_table(struct iommu_domain *domain, > + struct iommu_pasid_table_config *cfg) > +{ > + if (unlikely(!domain->ops->attach_pasid_table)) > + return -ENODEV; > + > + return domain->ops->attach_pasid_table(domain, cfg); > +} > +EXPORT_SYMBOL_GPL(iommu_attach_pasid_table); > + > +void iommu_detach_pasid_table(struct iommu_domain *domain) > +{ > + if (unlikely(!domain->ops->detach_pasid_table)) > + return; > + > + domain->ops->detach_pasid_table(domain); > +} > +EXPORT_SYMBOL_GPL(iommu_detach_pasid_table); > + > static void __iommu_detach_device(struct iommu_domain *domain, > struct device *dev) > { > diff --git a/include/linux/iommu.h b/include/linux/iommu.h > index b38e0c100940..7045e26f3a7d 100644 > --- a/include/linux/iommu.h > +++ b/include/linux/iommu.h > @@ -187,6 +187,8 @@ struct iommu_resv_region { > * @domain_window_disable: Disable a particular window for a domain > * @of_xlate: add OF master IDs to iommu grouping > * @pgsize_bitmap: bitmap of all possible supported page sizes > + * @attach_pasid_table: attach a pasid table > + * @detach_pasid_table: detach the pasid table Should go before pgsize_bitmap > */ > struct iommu_ops { > bool (*capable)(enum iommu_cap); > @@ -229,6 +231,10 @@ struct iommu_ops { > int (*of_xlate)(struct device *dev, struct of_phandle_args *args); > bool (*is_attach_deferred)(struct iommu_domain *domain, struct device *dev); > > + int (*attach_pasid_table)(struct iommu_domain *domain, > + struct iommu_pasid_table_config *cfg); > + void (*detach_pasid_table)(struct iommu_domain *domain); > + > unsigned long pgsize_bitmap; > }; > > @@ -339,6 +345,9 @@ extern int iommu_attach_device(struct iommu_domain *domain, > struct device *dev); > extern void iommu_detach_device(struct iommu_domain *domain, > struct device *dev); > +extern int iommu_attach_pasid_table(struct iommu_domain *domain, > + struct iommu_pasid_table_config *cfg); > +extern void iommu_detach_pasid_table(struct iommu_domain *domain); > extern struct iommu_domain *iommu_get_domain_for_dev(struct device *dev); > extern struct iommu_domain *iommu_get_dma_domain(struct device *dev); > extern int iommu_map(struct iommu_domain *domain, unsigned long iova, > @@ -777,6 +786,19 @@ const struct iommu_ops *iommu_ops_from_fwnode(struct fwnode_handle *fwnode) > return NULL; > } > > +static inline > +int iommu_attach_pasid_table(struct iommu_domain *domain, > + struct iommu_pasid_table_config *cfg) > +{ > + return -ENODEV; > +} > + > +static inline > +void iommu_detach_pasid_table(struct iommu_domain *domain) > +{ > + return -ENODEV; No return here. With that fixed: Reviewed-by: Jean-Philippe Brucker > +} > + > #endif /* CONFIG_IOMMU_API */ > > #ifdef CONFIG_IOMMU_DEBUGFS > diff --git a/include/uapi/linux/iommu.h b/include/uapi/linux/iommu.h > index 7ebf23ed6ccb..e9065bfa5b24 100644 > --- a/include/uapi/linux/iommu.h > +++ b/include/uapi/linux/iommu.h > @@ -112,4 +112,51 @@ struct iommu_fault { > struct iommu_fault_page_request prm; > }; > }; > + > +/** > + * SMMUv3 Stream Table Entry stage 1 related information > + * The PASID table is referred to as the context descriptor (CD) table. > + * > + * @s1fmt: STE s1fmt (format of the CD table: single CD, linear table > + or 2-level table) > + * @s1dss: STE s1dss (specifies the behavior when pasid_bits != 0 > + and no pasid is passed along with the incoming transaction) > + * Please refer to the smmu 3.x spec (ARM IHI 0070A) for full details > + */ > +struct iommu_pasid_smmuv3 { > +#define PASID_TABLE_SMMUV3_CFG_VERSION_1 1 > + __u32 version; > + __u8 s1fmt; > + __u8 s1dss; > + __u8 padding[2]; > +}; > + > +/** > + * PASID table data used to bind guest PASID table to the host IOMMU > + * Note PASID table corresponds to the Context Table on ARM SMMUv3. > + * > + * @version: API version to prepare for future extensions > + * @format: format of the PASID table > + * @base_ptr: guest physical address of the PASID table > + * @pasid_bits: number of PASID bits used in the PASID table > + * @config: indicates whether the guest translation stage must > + * be translated, bypassed or aborted. > + */ > +struct iommu_pasid_table_config { > +#define PASID_TABLE_CFG_VERSION_1 1 > + __u32 version; > +#define IOMMU_PASID_FORMAT_SMMUV3 1 > + __u32 format; > + __u64 base_ptr; > + __u8 pasid_bits; > +#define IOMMU_PASID_CONFIG_TRANSLATE 1 > +#define IOMMU_PASID_CONFIG_BYPASS 2 > +#define IOMMU_PASID_CONFIG_ABORT 3 > + __u8 config; > + __u8 padding[6]; > + union { > + struct iommu_pasid_smmuv3 smmuv3; > + }; > +}; > + > #endif /* _UAPI_IOMMU_H */ >