On Thu, Oct 26, 2023 at 10:49:26AM +0800, Lu Baolu wrote:
- @IOMMU_HWPT_ALLOC_IOPF_CAPABLE: User is capable of handling IO page faults.
This does not seem like the best name?
Probably like this given my remark in the cover letter:
--- a/include/uapi/linux/iommufd.h +++ b/include/uapi/linux/iommufd.h @@ -359,6 +359,7 @@ struct iommu_vfio_ioas { enum iommufd_hwpt_alloc_flags { IOMMU_HWPT_ALLOC_NEST_PARENT = 1 << 0, IOMMU_HWPT_ALLOC_DIRTY_TRACKING = 1 << 1, + IOMMU_HWPT_IOPFD_FD_VALID = 1 << 2, };
/** @@ -440,6 +441,7 @@ struct iommu_hwpt_alloc { __u32 data_type; __u32 data_len; __aligned_u64 data_uptr; + __s32 iopf_fd; }; #define IOMMU_HWPT_ALLOC _IO(IOMMUFD_TYPE, IOMMUFD_CMD_HWPT_ALLOC)
@@ -679,6 +688,62 @@ struct iommu_dev_data_arm_smmuv3 { __u32 sid; }; +/**
- struct iommu_hwpt_pgfault - iommu page fault data
- @size: sizeof(struct iommu_hwpt_pgfault)
- @flags: Combination of IOMMU_PGFAULT_FLAGS_ flags.
- PASID_VALID: @pasid field is valid
- LAST_PAGE: the last page fault in a group
- PRIV_DATA: @private_data field is valid
- RESP_NEEDS_PASID: the page response must have the same
PASID value as the page request.
- @dev_id: id of the originated device
- @pasid: Process Address Space ID
- @grpid: Page Request Group Index
- @perm: requested page permissions (IOMMU_PGFAULT_PERM_* values)
- @addr: page address
- @private_data: device-specific private information
- */
+struct iommu_hwpt_pgfault {
- __u32 size;
- __u32 flags;
+#define IOMMU_PGFAULT_FLAGS_PASID_VALID (1 << 0) +#define IOMMU_PGFAULT_FLAGS_LAST_PAGE (1 << 1) +#define IOMMU_PGFAULT_FLAGS_PRIV_DATA (1 << 2) +#define IOMMU_PGFAULT_FLAGS_RESP_NEEDS_PASID (1 << 3)
- __u32 dev_id;
- __u32 pasid;
- __u32 grpid;
- __u32 perm;
+#define IOMMU_PGFAULT_PERM_READ (1 << 0) +#define IOMMU_PGFAULT_PERM_WRITE (1 << 1) +#define IOMMU_PGFAULT_PERM_EXEC (1 << 2) +#define IOMMU_PGFAULT_PERM_PRIV (1 << 3)
- __u64 addr;
- __u64 private_data[2];
+};
This mixed #define is not the style, these should be in enums, possibly with kdocs
Use __aligned_u64 also
+/**
- struct iommu_hwpt_response - IOMMU page fault response
- @size: sizeof(struct iommu_hwpt_response)
- @flags: Must be set to 0
- @hwpt_id: hwpt ID of target hardware page table for the response
- @dev_id: device ID of target device for the response
- @pasid: Process Address Space ID
- @grpid: Page Request Group Index
- @code: response code. The supported codes include:
0: Successful; 1: Response Failure; 2: Invalid Request.- */
+struct iommu_hwpt_page_response {
- __u32 size;
- __u32 flags;
- __u32 hwpt_id;
- __u32 dev_id;
- __u32 pasid;
- __u32 grpid;
- __u32 code;
+};
Is it OK to have the user pass in all this detailed information? Is it a security problem if the user lies? Ie shouldn't we only ack page faults we actually have outstanding?
IOW should iommu_hwpt_pgfault just have a 'response_cookie' generated by the kernel that should be placed here? The kernel would keep track of all this internal stuff?
Jason