Currently, devices that are emulated inside KVM are configured in a hardcoded manner based on an assumption that any given architecture only has one way to do it. If there's any need to access device state, it is done through inflexible one-purpose-only IOCTLs (e.g. KVM_GET/SET_LAPIC). Defining new IOCTLs for every little thing is cumbersome and depletes a limited numberspace. This API provides a mechanism to instantiate a device of a certain type, returning an ID that can be used to set/get attributes of the device. Attributes may include configuration parameters (e.g. register base address), device state, operational commands, etc. It is similar to the ONE_REG API, except that it acts on devices rather than vcpus. Both device types and individual attributes can be tested without having to create the device or get/set the attribute, without the need for separately managing enumerated capabilities.
Showing the changes to include/uapi/linux (1 of 5 files). Show all
Unified · Split
| @@ -666,6 +666,7 @@ struct kvm_ppc_smmu_info { · 665 unmodified lines | |||
| 666 | #define KVM_CAP_PPC_EPR 86 | 666 | #define KVM_CAP_PPC_EPR 86 |
| 667 | #define KVM_CAP_ARM_PSCI 87 | 667 | #define KVM_CAP_ARM_PSCI 87 |
| 668 | #define KVM_CAP_ARM_SET_DEVICE_ADDR 88 | 668 | #define KVM_CAP_ARM_SET_DEVICE_ADDR 88 |
| 669 | #define KVM_CAP_DEVICE_CTRL 89 | ||
| 669 | 670 | ||
| 670 | #ifdef KVM_CAP_IRQ_ROUTING | 671 | #ifdef KVM_CAP_IRQ_ROUTING |
| 671 | 672 | ||
| @@ -818,6 +819,24 @@ struct kvm_arm_device_addr { · 146 unmodified lines | |||
| 818 | __u64 addr; | 819 | __u64 addr; |
| 819 | }; | 820 | }; |
| 820 | 821 | ||
| 822 | /* | ||
| 823 | * Device control API, available with KVM_CAP_DEVICE_CTRL | ||
| 824 | */ | ||
| 825 | #define KVM_CREATE_DEVICE_TEST 1 | ||
| 826 | |||
| 827 | struct kvm_create_device { | ||
| 828 | __u32 type; /* in: KVM_DEV_TYPE_xxx */ | ||
| 829 | __u32 fd; /* out: device handle */ | ||
| 830 | __u32 flags; /* in: KVM_CREATE_DEVICE_xxx */ | ||
| 831 | }; | ||
| 832 | |||
| 833 | struct kvm_device_attr { | ||
| 834 | __u32 flags; /* no flags currently defined */ | ||
| 835 | __u32 group; /* device-defined */ | ||
| 836 | __u64 attr; /* group-defined */ | ||
| 837 | __u64 addr; /* userspace address of attr data */ | ||
| 838 | }; | ||
| 839 | |||
| 821 | /* | 840 | /* |
| 822 | * ioctls for VM fds | 841 | * ioctls for VM fds |
| 823 | */ | 842 | */ |
| @@ -906,6 +925,14 @@ struct kvm_s390_ucas_mapping { · 82 unmodified lines | |||
| 906 | /* Available with KVM_CAP_ARM_SET_DEVICE_ADDR */ | 925 | /* Available with KVM_CAP_ARM_SET_DEVICE_ADDR */ |
| 907 | #define KVM_ARM_SET_DEVICE_ADDR _IOW(KVMIO, 0xab, struct kvm_arm_device_addr) | 926 | #define KVM_ARM_SET_DEVICE_ADDR _IOW(KVMIO, 0xab, struct kvm_arm_device_addr) |
| 908 | 927 | ||
| 928 | /* ioctl for vm fd */ | ||
| 929 | #define KVM_CREATE_DEVICE _IOWR(KVMIO, 0xe0, struct kvm_create_device) | ||
| 930 | |||
| 931 | /* ioctls for fds returned by KVM_CREATE_DEVICE */ | ||
| 932 | #define KVM_SET_DEVICE_ATTR _IOW(KVMIO, 0xe1, struct kvm_device_attr) | ||
| 933 | #define KVM_GET_DEVICE_ATTR _IOW(KVMIO, 0xe2, struct kvm_device_attr) | ||
| 934 | #define KVM_HAS_DEVICE_ATTR _IOW(KVMIO, 0xe3, struct kvm_device_attr) | ||
| 935 | |||
| 909 | /* | 936 | /* |
| 910 | * ioctls for vcpu fds | 937 | * ioctls for vcpu fds |
| 911 | */ | 938 | */ |