kernel/linux.git/include/uapi/linux/iommu.h, branch v6.6.132

iommu: Remove guest pasid related interfaces and definitions

2022-02-28T12:25:48+00:00

The guest pasid related uapi interfaces and definitions are not referenced anywhere in the tree. We've also reached a consensus to replace them with a new iommufd design. Remove them to avoid dead code. Signed-off-by: Lu Baolu Reviewed-by: Christoph Hellwig Reviewed-by: Jason Gunthorpe Link: https://lore.kernel.org/r/20220216025249.3459465-3-baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel

iommu/vt-d: Enable write protect propagation from guest

2021-03-18T10:42:46+00:00

Write protect bit, when set, inhibits supervisor writes to the read-only pages. In guest supervisor shared virtual addressing (SVA), write-protect should be honored upon guest bind supervisor PASID request. This patch extends the VT-d portion of the IOMMU UAPI to include WP bit. WPE bit of the supervisor PASID entry will be set to match CPU CR0.WP bit. Signed-off-by: Sanjay Kumar Signed-off-by: Jacob Pan Acked-by: Lu Baolu Link: https://lore.kernel.org/r/1614680040-1989-3-git-send-email-jacob.jun.pan@linux.intel.com Signed-off-by: Joerg Roedel

iommu/vt-d: Check UAPI data processed by IOMMU core

2020-10-01T12:52:46+00:00

IOMMU generic layer already does sanity checks on UAPI data for version match and argsz range based on generic information. This patch adjusts the following data checking responsibilities: - removes the redundant version check from VT-d driver - removes the check for vendor specific data size - adds check for the use of reserved/undefined flags Signed-off-by: Jacob Pan Reviewed-by: Eric Auger Link: https://lore.kernel.org/r/1601051567-54787-7-git-send-email-jacob.jun.pan@linux.intel.com Signed-off-by: Joerg Roedel

iommu/uapi: Handle data and argsz filled by users

2020-10-01T12:52:46+00:00

IOMMU user APIs are responsible for processing user data. This patch changes the interface such that user pointers can be passed into IOMMU code directly. Separate kernel APIs without user pointers are introduced for in-kernel users of the UAPI functionality. IOMMU UAPI data has a user filled argsz field which indicates the data length of the structure. User data is not trusted, argsz must be validated based on the current kernel data size, mandatory data size, and feature flags. User data may also be extended, resulting in possible argsz increase. Backward compatibility is ensured based on size and flags (or the functional equivalent fields) checking. This patch adds sanity checks in the IOMMU layer. In addition to argsz, reserved/unused fields in padding, flags, and version are also checked. Details are documented in Documentation/userspace-api/iommu.rst Signed-off-by: Liu Yi L Signed-off-by: Jacob Pan Reviewed-by: Jean-Philippe Brucker Reviewed-by: Eric Auger Link: https://lore.kernel.org/r/1601051567-54787-6-git-send-email-jacob.jun.pan@linux.intel.com Signed-off-by: Joerg Roedel

iommu/uapi: Use named union for user data

2020-10-01T12:52:46+00:00

IOMMU UAPI data size is filled by the user space which must be validated by the kernel. To ensure backward compatibility, user data can only be extended by either re-purpose padding bytes or extend the variable sized union at the end. No size change is allowed before the union. Therefore, the minimum size is the offset of the union. To use offsetof() on the union, we must make it named. Signed-off-by: Jacob Pan Reviewed-by: Lu Baolu Reviewed-by: Eric Auger Link: https://lore.kernel.org/linux-iommu/20200611145518.0c2817d6@x1.home/ Link: https://lore.kernel.org/r/1601051567-54787-4-git-send-email-jacob.jun.pan@linux.intel.com Signed-off-by: Joerg Roedel

iommu/uapi: Add argsz for user filled data

2020-10-01T12:52:46+00:00

As IOMMU UAPI gets extended, user data size may increase. To support backward compatibiliy, this patch introduces a size field to each UAPI data structures. It is *always* the responsibility for the user to fill in the correct size. Padding fields are adjusted to ensure 8 byte alignment. Specific scenarios for user data handling are documented in: Documentation/userspace-api/iommu.rst As there is no current users of the API, struct version is not incremented. Signed-off-by: Liu Yi L Signed-off-by: Jacob Pan Reviewed-by: Eric Auger Link: https://lore.kernel.org/r/1601051567-54787-3-git-send-email-jacob.jun.pan@linux.intel.com Signed-off-by: Joerg Roedel

iommu: Allow page responses without PASID

2020-06-30T09:49:21+00:00

Some PCIe devices do not expect a PASID value in PRI Page Responses. If the "PRG Response PASID Required" bit in the PRI capability is zero, then the OS should not set the PASID field. Similarly on Arm SMMU, responses to stall events do not have a PASID. Currently iommu_page_response() systematically checks that the PASID in the page response corresponds to the one in the page request. This can't work with virtualization because a page response coming from a guest OS won't have a PASID if the passed-through device does not require one. Add a flag to page requests that declares whether the corresponding response needs to have a PASID. When this flag isn't set, allow page responses without PASID. Reported-by: Shameerali Kolothum Thodi Signed-off-by: Jean-Philippe Brucker Link: https://lore.kernel.org/r/20200616144712.748818-1-jean-philippe@linaro.org Signed-off-by: Joerg Roedel

iommu/vt-d: Add nested translation helper function

2020-05-18T13:37:25+00:00

Nested translation mode is supported in VT-d 3.0 Spec.CH 3.8. With PASID granular translation type set to 0x11b, translation result from the first level(FL) also subject to a second level(SL) page table translation. This mode is used for SVA virtualization, where FL performs guest virtual to guest physical translation and SL performs guest physical to host physical translation. This patch adds a helper function for setting up nested translation where second level comes from a domain and first level comes from a guest PGD. Signed-off-by: Jacob Pan Signed-off-by: Liu Yi L Signed-off-by: Lu Baolu Reviewed-by: Eric Auger Link: https://lore.kernel.org/r/20200516062101.29541-4-baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel

iommu: Introduce guest PASID bind function

2019-10-15T11:34:43+00:00

Guest shared virtual address (SVA) may require host to shadow guest PASID tables. Guest PASID can also be allocated from the host via enlightened interfaces. In this case, guest needs to bind the guest mm, i.e. cr3 in guest physical address to the actual PASID table in the host IOMMU. Nesting will be turned on such that guest virtual address can go through a two level translation: - 1st level translates GVA to GPA - 2nd level translates GPA to HPA This patch introduces APIs to bind guest PASID data to the assigned device entry in the physical IOMMU. See the diagram below for usage explanation. .-------------. .---------------------------. | vIOMMU | | Guest process mm, FL only | | | '---------------------------' .----------------/ | PASID Entry |--- PASID cache flush - '-------------' | | | V | | GP '-------------' Guest ------| Shadow |----------------------- GP->HP* --------- v v | Host v .-------------. .----------------------. | pIOMMU | | Bind FL for GVA-GPA | | | '----------------------' .----------------/ | | PASID Entry | V (Nested xlate) '----------------\.---------------------. | | |Set SL to GPA-HPA | | | '---------------------' '-------------' Where: - FL = First level/stage one page tables - SL = Second level/stage two page tables - GP = Guest PASID - HP = Host PASID * Conversion needed if non-identity GP-HP mapping option is chosen. Signed-off-by: Jacob Pan Signed-off-by: Liu Yi L Reviewed-by: Jean-Philippe Brucker Reviewed-by: Jean-Philippe Brucker Reviewed-by: Eric Auger Signed-off-by: Joerg Roedel

iommu: Introduce cache_invalidate API

2019-10-15T11:34:04+00:00

In any virtualization use case, when the first translation stage is "owned" by the guest OS, the host IOMMU driver has no knowledge of caching structure updates unless the guest invalidation activities are trapped by the virtualizer and passed down to the host. Since the invalidation data can be obtained from user space and will be written into physical IOMMU, we must allow security check at various layers. Therefore, generic invalidation data format are proposed here, model specific IOMMU drivers need to convert them into their own format. Signed-off-by: Yi L Liu Signed-off-by: Jacob Pan Signed-off-by: Ashok Raj Signed-off-by: Eric Auger Signed-off-by: Jean-Philippe Brucker Reviewed-by: Jean-Philippe Brucker Reviewed-by: Eric Auger Signed-off-by: Joerg Roedel