diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index 3c248f772ae6..4b5fa2571efa 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -115,12 +115,17 @@ will access the virtual machine's physical address space; offset zero corresponds to guest physical address zero. Use of mmap() on a VM fd is discouraged if userspace memory allocation (KVM_CAP_USER_MEMORY) is available. -You most certainly want to use 0 as machine type. +You probably want to use 0 as machine type. In order to create user controlled virtual machines on S390, check KVM_CAP_S390_UCONTROL and use the flag KVM_VM_S390_UCONTROL as privileged user (CAP_SYS_ADMIN). +To use hardware assisted virtualization on MIPS (VZ ASE) rather than +the default trap & emulate implementation (which changes the virtual +memory layout to fit in user mode), check KVM_CAP_MIPS_VZ and use the +flag KVM_VM_MIPS_VZ. + 4.3 KVM_GET_MSR_INDEX_LIST @@ -4147,3 +4152,43 @@ This capability, if KVM_CHECK_EXTENSION indicates that it is available, means that that the kernel can support guests using the hashed page table MMU defined in Power ISA V3.00 (as implemented in the POWER9 processor), including in-memory segment tables. + +8.5 KVM_CAP_MIPS_VZ + +Architectures: mips + +This capability, if KVM_CHECK_EXTENSION on the main kvm handle indicates that +it is available, means that full hardware assisted virtualization capabilities +of the hardware are available for use through KVM. An appropriate +KVM_VM_MIPS_* type must be passed to KVM_CREATE_VM to create a VM which +utilises it. + +If KVM_CHECK_EXTENSION on a kvm VM handle indicates that this capability is +available, it means that the VM is using full hardware assisted virtualization +capabilities of the hardware. This is useful to check after creating a VM with +KVM_VM_MIPS_DEFAULT. + +The value returned by KVM_CHECK_EXTENSION should be compared against known +values (see below). All other values are reserved. This is to allow for the +possibility of other hardware assisted virtualization implementations which +may be incompatible with the MIPS VZ ASE. + + 0: The trap & emulate implementation is in use to run guest code in user + mode. Guest virtual memory segments are rearranged to fit the guest in the + user mode address space. + + 1: The MIPS VZ ASE is in use, providing full hardware assisted + virtualization, including standard guest virtual memory segments. + +8.6 KVM_CAP_MIPS_TE + +Architectures: mips + +This capability, if KVM_CHECK_EXTENSION on the main kvm handle indicates that +it is available, means that the trap & emulate implementation is available to +run guest code in user mode, even if KVM_CAP_MIPS_VZ indicates that hardware +assisted virtualisation is also available. KVM_VM_MIPS_TE (0) must be passed +to KVM_CREATE_VM to create a VM which utilises it. + +If KVM_CHECK_EXTENSION on a kvm VM handle indicates that this capability is +available, it means that the VM is using trap & emulate. diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c index c507533ef6ea..476ece99bf3b 100644 --- a/arch/mips/kvm/mips.c +++ b/arch/mips/kvm/mips.c @@ -107,6 +107,14 @@ void kvm_arch_check_processor_compat(void *rtn) int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) { + switch (type) { + case KVM_VM_MIPS_TE: + break; + default: + /* Unsupported KVM type */ + return -EINVAL; + }; + /* Allocate page table to map GPA -> RPA */ kvm->arch.gpa_mm.pgd = kvm_pgd_alloc(); if (!kvm->arch.gpa_mm.pgd) @@ -1038,6 +1046,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) case KVM_CAP_READONLY_MEM: case KVM_CAP_SYNC_MMU: case KVM_CAP_IMMEDIATE_EXIT: + case KVM_CAP_MIPS_TE: r = 1; break; case KVM_CAP_COALESCED_MMIO: diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index f51d5082a377..58ddedce4235 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -702,6 +702,10 @@ struct kvm_ppc_resize_hpt { #define KVM_VM_PPC_HV 1 #define KVM_VM_PPC_PR 2 +/* on MIPS, 0 forces trap & emulate, 1 forces VZ ASE */ +#define KVM_VM_MIPS_TE 0 +#define KVM_VM_MIPS_VZ 1 + #define KVM_S390_SIE_PAGE_OFFSET 1 /* @@ -883,6 +887,8 @@ struct kvm_ppc_resize_hpt { #define KVM_CAP_PPC_MMU_RADIX 134 #define KVM_CAP_PPC_MMU_HASH_V3 135 #define KVM_CAP_IMMEDIATE_EXIT 136 +#define KVM_CAP_MIPS_VZ 137 +#define KVM_CAP_MIPS_TE 138 #ifdef KVM_CAP_IRQ_ROUTING