Commit 938c8745 authored by Sean Christopherson's avatar Sean Christopherson Committed by Paolo Bonzini
Browse files

KVM: x86: Introduce "struct kvm_caps" to track misc caps/settings 



Add kvm_caps to hold a variety of capabilites and defaults that aren't
handled by kvm_cpu_caps because they aren't CPUID bits in order to reduce
the amount of boilerplate code required to add a new feature.  The vast
majority (all?) of the caps interact with vendor code and are written
only during initialization, i.e. should be tagged __read_mostly, declared
extern in x86.h, and exported.

No functional change intended.

Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
Message-Id: <20220524135624.22988-4-chenyi.qiang@intel.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 30267b43

arch/x86/include/asm/kvm_host.h

+0 −15
Original line number Diff line number Diff line
@@ -1664,21 +1664,6 @@ extern bool tdp_enabled; 


u64 vcpu_tsc_khz(struct kvm_vcpu *vcpu);



/* control of guest tsc rate supported? */

extern bool kvm_has_tsc_control;

/* maximum supported tsc_khz for guests */

extern u32  kvm_max_guest_tsc_khz;

/* number of bits of the fractional part of the TSC scaling ratio */

extern u8   kvm_tsc_scaling_ratio_frac_bits;

/* maximum allowed value of TSC scaling ratio */

extern u64  kvm_max_tsc_scaling_ratio;

/* 1ull << kvm_tsc_scaling_ratio_frac_bits */

extern u64  kvm_default_tsc_scaling_ratio;

/* bus lock detection supported? */

extern bool kvm_has_bus_lock_exit;



extern u64 kvm_mce_cap_supported;



/*

 * EMULTYPE_NO_DECODE - Set when re-emulating an instruction (after completing

 *			userspace I/O) to indicate that the emulation context

arch/x86/kvm/cpuid.c

+4 −4
Original line number Diff line number Diff line
@@ -200,7 +200,7 @@ void kvm_update_pv_runtime(struct kvm_vcpu *vcpu) 


/*

 * Calculate guest's supported XCR0 taking into account guest CPUID data and

 * supported_xcr0 (comprised of host configuration and KVM_SUPPORTED_XCR0).

 * KVM's supported XCR0 (comprised of host's XCR0 and KVM_SUPPORTED_XCR0).

 */

static u64 cpuid_get_supported_xcr0(struct kvm_cpuid_entry2 *entries, int nent)

{
@@ -210,7 +210,7 @@ static u64 cpuid_get_supported_xcr0(struct kvm_cpuid_entry2 *entries, int nent) 
	if (!best)

		return 0;



	return (best->eax | ((u64)best->edx << 32)) & supported_xcr0;

	return (best->eax | ((u64)best->edx << 32)) & kvm_caps.supported_xcr0;

}



static void __kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu, struct kvm_cpuid_entry2 *entries,
@@ -912,8 +912,8 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function) 
		}

		break;

	case 0xd: {

		u64 permitted_xcr0 = supported_xcr0 & xstate_get_guest_group_perm();

		u64 permitted_xss = supported_xss;

		u64 permitted_xcr0 = kvm_caps.supported_xcr0 & xstate_get_guest_group_perm();

		u64 permitted_xss = kvm_caps.supported_xss;



		entry->eax &= permitted_xcr0;

		entry->ebx = xstate_required_size(permitted_xcr0, false);

arch/x86/kvm/debugfs.c

+2 −2
Original line number Diff line number Diff line
@@ -48,7 +48,7 @@ DEFINE_SIMPLE_ATTRIBUTE(vcpu_tsc_scaling_fops, vcpu_get_tsc_scaling_ratio, NULL, 


static int vcpu_get_tsc_scaling_frac_bits(void *data, u64 *val)

{

	*val = kvm_tsc_scaling_ratio_frac_bits;

	*val = kvm_caps.tsc_scaling_ratio_frac_bits;

	return 0;

}
@@ -66,7 +66,7 @@ void kvm_arch_create_vcpu_debugfs(struct kvm_vcpu *vcpu, struct dentry *debugfs_ 
				    debugfs_dentry, vcpu,

				    &vcpu_timer_advance_ns_fops);



	if (kvm_has_tsc_control) {

	if (kvm_caps.has_tsc_control) {

		debugfs_create_file("tsc-scaling-ratio", 0444,

				    debugfs_dentry, vcpu,

				    &vcpu_tsc_scaling_fops);

arch/x86/kvm/lapic.c

+1 −1
Original line number Diff line number Diff line
@@ -1603,7 +1603,7 @@ static inline void __wait_lapic_expire(struct kvm_vcpu *vcpu, u64 guest_cycles) 
	 * that __delay() uses delay_tsc whenever the hardware has TSC, thus

	 * always for VMX enabled hardware.

	 */

	if (vcpu->arch.tsc_scaling_ratio == kvm_default_tsc_scaling_ratio) {

	if (vcpu->arch.tsc_scaling_ratio == kvm_caps.default_tsc_scaling_ratio) {

		__delay(min(guest_cycles,

			nsec_to_cycles(vcpu, timer_advance_ns)));

	} else {

arch/x86/kvm/svm/nested.c

+2 −2
Original line number Diff line number Diff line
@@ -674,7 +674,7 @@ static void nested_vmcb02_prepare_control(struct vcpu_svm *svm, 


	vmcb02->control.tsc_offset = vcpu->arch.tsc_offset;



	if (svm->tsc_ratio_msr != kvm_default_tsc_scaling_ratio) {

	if (svm->tsc_ratio_msr != kvm_caps.default_tsc_scaling_ratio) {

		WARN_ON(!svm->tsc_scaling_enabled);

		nested_svm_update_tsc_ratio_msr(vcpu);

	}
@@ -1031,7 +1031,7 @@ int nested_svm_vmexit(struct vcpu_svm *svm) 
		vmcb_mark_dirty(vmcb01, VMCB_INTERCEPTS);

	}



	if (svm->tsc_ratio_msr != kvm_default_tsc_scaling_ratio) {

	if (svm->tsc_ratio_msr != kvm_caps.default_tsc_scaling_ratio) {

		WARN_ON(!svm->tsc_scaling_enabled);

		vcpu->arch.tsc_scaling_ratio = vcpu->arch.l1_tsc_scaling_ratio;

		__svm_write_tsc_multiplier(vcpu->arch.tsc_scaling_ratio);