[PATCH v12 2/6] iommu/uapi: Add argsz for user filled data
From: Jacob Pan <hidden>
Date: 2020-09-25 16:31:15
Also in:
linux-iommu, lkml
Subsystem:
the rest · Maintainer:
Linus Torvalds
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. Reviewed-by: Eric Auger <eric.auger@redhat.com> Signed-off-by: Liu Yi L <redacted> Signed-off-by: Jacob Pan <redacted> --- include/uapi/linux/iommu.h | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-)
diff --git a/include/uapi/linux/iommu.h b/include/uapi/linux/iommu.h
index c2b2caf9ed41..b42acc8fe007 100644
--- a/include/uapi/linux/iommu.h
+++ b/include/uapi/linux/iommu.h@@ -139,6 +139,7 @@ enum iommu_page_response_code { /** * struct iommu_page_response - Generic page response information + * @argsz: User filled size of this data * @version: API version of this structure * @flags: encodes whether the corresponding fields are valid * (IOMMU_FAULT_PAGE_RESPONSE_* values)
@@ -147,6 +148,7 @@ enum iommu_page_response_code { * @code: response code from &enum iommu_page_response_code */ struct iommu_page_response { + __u32 argsz; #define IOMMU_PAGE_RESP_VERSION_1 1 __u32 version; #define IOMMU_PAGE_RESP_PASID_VALID (1 << 0)
@@ -222,6 +224,7 @@ struct iommu_inv_pasid_info { /** * struct iommu_cache_invalidate_info - First level/stage invalidation * information + * @argsz: User filled size of this data * @version: API version of this structure * @cache: bitfield that allows to select which caches to invalidate * @granularity: defines the lowest granularity used for the invalidation:
@@ -250,6 +253,7 @@ struct iommu_inv_pasid_info { * must support the used granularity. */ struct iommu_cache_invalidate_info { + __u32 argsz; #define IOMMU_CACHE_INVALIDATE_INFO_VERSION_1 1 __u32 version; /* IOMMU paging structure cache */
@@ -259,7 +263,7 @@ struct iommu_cache_invalidate_info { #define IOMMU_CACHE_INV_TYPE_NR (3) __u8 cache; __u8 granularity; - __u8 padding[2]; + __u8 padding[6]; union { struct iommu_inv_pasid_info pasid_info; struct iommu_inv_addr_info addr_info;
@@ -296,6 +300,7 @@ struct iommu_gpasid_bind_data_vtd { /** * struct iommu_gpasid_bind_data - Information about device and guest PASID binding + * @argsz: User filled size of this data * @version: Version of this data structure * @format: PASID table entry format * @flags: Additional information on guest bind request
@@ -313,17 +318,18 @@ struct iommu_gpasid_bind_data_vtd { * PASID to host PASID based on this bind data. */ struct iommu_gpasid_bind_data { + __u32 argsz; #define IOMMU_GPASID_BIND_VERSION_1 1 __u32 version; #define IOMMU_PASID_FORMAT_INTEL_VTD 1 __u32 format; + __u32 addr_width; #define IOMMU_SVA_GPASID_VAL (1 << 0) /* guest PASID valid */ __u64 flags; __u64 gpgd; __u64 hpasid; __u64 gpasid; - __u32 addr_width; - __u8 padding[12]; + __u8 padding[8]; /* Vendor specific data */ union { struct iommu_gpasid_bind_data_vtd vtd;
--
2.7.4