Re: [PATCH v5 2/5] iommu/uapi: Add argsz for user filled data
On Fri, 17 Jul 2020 15:44:23 +0200 Auger Eric wrote: > Hi Jacob, > > On 7/16/20 8:45 PM, 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 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 > > > > Signed-off-by: Liu Yi L > > Signed-off-by: Jacob Pan > > --- > > 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 > Don't you need to incr the version for all the modified structs? not literal "flags" but @cache and @granularity are flags in reality. I think that is OK. I also updated document to say "flags or equivalent". > > __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; > so there is no "flags" field in this struct. Is it OK? > > /* IOMMU paging structure cache */ > > @@ -255,7 +259,7 @@ struct iommu_cache_invalidate_info { > > #define IOMMU_CACHE_INV_TYPE_NR(3) > > __u8cache; > > __u8granularity; > > - __u8padding[2]; > > + __u8padding[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_11 > > __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; > > > Thanks > > Eric > [Jacob Pan] ___ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
Re: [PATCH v5 2/5] iommu/uapi: Add argsz for user filled data
Hi Jacob, On 7/16/20 8:45 PM, 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 > 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 > > Signed-off-by: Liu Yi L > Signed-off-by: Jacob Pan > --- > 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_11 Don't you need to incr the version for all the modified structs? > __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; so there is no "flags" field in this struct. Is it OK? > /* IOMMU paging structure cache */ > @@ -255,7 +259,7 @@ struct iommu_cache_invalidate_info { > #define IOMMU_CACHE_INV_TYPE_NR (3) > __u8cache; > __u8granularity; > - __u8padding[2]; > + __u8padding[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; > Thanks Eric ___ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
[PATCH v5 2/5] iommu/uapi: Add argsz for user filled data
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 Signed-off-by: Liu Yi L Signed-off-by: Jacob Pan --- 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) __u8cache; __u8granularity; - __u8padding[2]; + __u8padding[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_11 __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 ___ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu