From 344d9588a9df06182684168be4f1408b55c7da3e Mon Sep 17 00:00:00 2001 From: Gleb Natapov Date: Thu, 14 Oct 2010 11:22:50 +0200 Subject: KVM: Add PV MSR to enable asynchronous page faults delivery. Guest enables async PF vcpu functionality using this MSR. Reviewed-by: Rik van Riel Signed-off-by: Gleb Natapov Signed-off-by: Marcelo Tosatti --- arch/x86/include/asm/kvm_host.h | 2 ++ arch/x86/include/asm/kvm_para.h | 4 ++++ arch/x86/kvm/x86.c | 38 ++++++++++++++++++++++++++++++++++++-- 3 files changed, 42 insertions(+), 2 deletions(-) (limited to 'arch') diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index c3076bcf5ef7..0d7039804b4c 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -419,6 +419,8 @@ struct kvm_vcpu_arch { struct { bool halted; gfn_t gfns[roundup_pow_of_two(ASYNC_PF_PER_VCPU)]; + struct gfn_to_hva_cache data; + u64 msr_val; } apf; }; diff --git a/arch/x86/include/asm/kvm_para.h b/arch/x86/include/asm/kvm_para.h index e3faaaf4301e..8662ae0a035c 100644 --- a/arch/x86/include/asm/kvm_para.h +++ b/arch/x86/include/asm/kvm_para.h @@ -20,6 +20,7 @@ * are available. The use of 0x11 and 0x12 is deprecated */ #define KVM_FEATURE_CLOCKSOURCE2 3 +#define KVM_FEATURE_ASYNC_PF 4 /* The last 8 bits are used to indicate how to interpret the flags field * in pvclock structure. If no bits are set, all flags are ignored. @@ -32,9 +33,12 @@ /* Custom MSRs falls in the range 0x4b564d00-0x4b564dff */ #define MSR_KVM_WALL_CLOCK_NEW 0x4b564d00 #define MSR_KVM_SYSTEM_TIME_NEW 0x4b564d01 +#define MSR_KVM_ASYNC_PF_EN 0x4b564d02 #define KVM_MAX_MMU_OP_BATCH 32 +#define KVM_ASYNC_PF_ENABLED (1 << 0) + /* Operations for KVM_HC_MMU_OP */ #define KVM_MMU_OP_WRITE_PTE 1 #define KVM_MMU_OP_FLUSH_TLB 2 diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index bd254779d1cc..063c07296764 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -783,12 +783,12 @@ EXPORT_SYMBOL_GPL(kvm_get_dr); * kvm-specific. Those are put in the beginning of the list. */ -#define KVM_SAVE_MSRS_BEGIN 7 +#define KVM_SAVE_MSRS_BEGIN 8 static u32 msrs_to_save[] = { MSR_KVM_SYSTEM_TIME, MSR_KVM_WALL_CLOCK, MSR_KVM_SYSTEM_TIME_NEW, MSR_KVM_WALL_CLOCK_NEW, HV_X64_MSR_GUEST_OS_ID, HV_X64_MSR_HYPERCALL, - HV_X64_MSR_APIC_ASSIST_PAGE, + HV_X64_MSR_APIC_ASSIST_PAGE, MSR_KVM_ASYNC_PF_EN, MSR_IA32_SYSENTER_CS, MSR_IA32_SYSENTER_ESP, MSR_IA32_SYSENTER_EIP, MSR_STAR, #ifdef CONFIG_X86_64 @@ -1425,6 +1425,29 @@ static int set_msr_hyperv(struct kvm_vcpu *vcpu, u32 msr, u64 data) return 0; } +static int kvm_pv_enable_async_pf(struct kvm_vcpu *vcpu, u64 data) +{ + gpa_t gpa = data & ~0x3f; + + /* Bits 1:5 are resrved, Should be zero */ + if (data & 0x3e) + return 1; + + vcpu->arch.apf.msr_val = data; + + if (!(data & KVM_ASYNC_PF_ENABLED)) { + kvm_clear_async_pf_completion_queue(vcpu); + kvm_async_pf_hash_reset(vcpu); + return 0; + } + + if (kvm_gfn_to_hva_cache_init(vcpu->kvm, &vcpu->arch.apf.data, gpa)) + return 1; + + kvm_async_pf_wakeup_all(vcpu); + return 0; +} + int kvm_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data) { switch (msr) { @@ -1506,6 +1529,10 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data) } break; } + case MSR_KVM_ASYNC_PF_EN: + if (kvm_pv_enable_async_pf(vcpu, data)) + return 1; + break; case MSR_IA32_MCG_CTL: case MSR_IA32_MCG_STATUS: case MSR_IA32_MC0_CTL ... MSR_IA32_MC0_CTL + 4 * KVM_MAX_MCE_BANKS - 1: @@ -1782,6 +1809,9 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata) case MSR_KVM_SYSTEM_TIME_NEW: data = vcpu->arch.time; break; + case MSR_KVM_ASYNC_PF_EN: + data = vcpu->arch.apf.msr_val; + break; case MSR_IA32_P5_MC_ADDR: case MSR_IA32_P5_MC_TYPE: case MSR_IA32_MCG_CAP: @@ -1929,6 +1959,7 @@ int kvm_dev_ioctl_check_extension(long ext) case KVM_CAP_DEBUGREGS: case KVM_CAP_X86_ROBUST_SINGLESTEP: case KVM_CAP_XSAVE: + case KVM_CAP_ASYNC_PF: r = 1; break; case KVM_CAP_COALESCED_MMIO: @@ -5792,6 +5823,8 @@ free_vcpu: void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu) { + vcpu->arch.apf.msr_val = 0; + vcpu_load(vcpu); kvm_mmu_unload(vcpu); vcpu_put(vcpu); @@ -5811,6 +5844,7 @@ int kvm_arch_vcpu_reset(struct kvm_vcpu *vcpu) vcpu->arch.dr7 = DR7_FIXED_1; kvm_make_request(KVM_REQ_EVENT, vcpu); + vcpu->arch.apf.msr_val = 0; kvm_clear_async_pf_completion_queue(vcpu); kvm_async_pf_hash_reset(vcpu); -- cgit v1.2.3-59-g8ed1b