On Wed, 12 Aug 2020 18:59:14 +0200 Auger Eric <[email protected]> wrote:
> Hi, > > On 7/30/20 2:21 AM, Jacob Pan wrote: > > As IOMMU UAPI gets extended, user data size may increase. To support > > backward compatibiliy, this patch introduces a size field to each > > UAPI > s/compatibiliy/compatibility will fix > > 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 > > you may mention the struct version does not need to be incremented as > no IOCTL uses the structs yet. Yes, good point. I also mentioned in the doc that: "Version field is only reserved for the unlikely event of UAPI upgrade at its entirety." > > > > Signed-off-by: Liu Yi L <[email protected]> > > Signed-off-by: Jacob Pan <[email protected]> > > --- > > 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 e907b7091a46..d5e9014f690e 100644 > > --- a/include/uapi/linux/iommu.h > > +++ b/include/uapi/linux/iommu.h > > @@ -135,6 +135,7 @@ 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) > > @@ -143,6 +144,7 @@ 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) > > @@ -218,6 +220,7 @@ 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: @@ -246,6 +249,7 @@ 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 */ > > @@ -255,7 +259,7 @@ 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; > > @@ -292,6 +296,7 @@ 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 > > @@ -309,17 +314,18 @@ 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; > > > Reviewed-by: Eric Auger <[email protected]> > > Thanks > > Eric > [Jacob Pan]
