Commit 9ed3bf41 authored by Sean Christopherson's avatar Sean Christopherson
Browse files

KVM: x86/mmu: Move filling of Hyper-V's TLB range struct into Hyper-V code 



Refactor Hyper-V's range-based TLB flushing API to take a gfn+nr_pages
pair instead of a struct, and bury said struct in Hyper-V specific code.

Passing along two params generates much better code for the common case
where KVM is _not_ running on Hyper-V, as forwarding the flush on to
Hyper-V's hv_flush_remote_tlbs_range() from kvm_flush_remote_tlbs_range()
becomes a tail call.

Cc: David Matlack <dmatlack@google.com>
Reviewed-by: default avatarDavid Matlack <dmatlack@google.com>
Reviewed-by: default avatarVitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20230405003133.419177-3-seanjc@google.com


Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
parent 8a1300ff

arch/x86/include/asm/kvm_host.h

+2 −7
Original line number Diff line number Diff line
@@ -482,11 +482,6 @@ struct kvm_mmu { 
	u64 pdptrs[4]; /* pae */

};



struct kvm_tlb_range {

	u64 start_gfn;

	u64 pages;

};



enum pmc_type {

	KVM_PMC_GP = 0,

	KVM_PMC_FIXED,
@@ -1589,8 +1584,8 @@ struct kvm_x86_ops { 
	void (*flush_tlb_all)(struct kvm_vcpu *vcpu);

	void (*flush_tlb_current)(struct kvm_vcpu *vcpu);

	int  (*flush_remote_tlbs)(struct kvm *kvm);

	int  (*flush_remote_tlbs_range)(struct kvm *kvm,

					struct kvm_tlb_range *range);

	int  (*flush_remote_tlbs_range)(struct kvm *kvm, gfn_t gfn,

					gfn_t nr_pages);



	/*

	 * Flush any TLB entries associated with the given GVA.

arch/x86/kvm/kvm_onhyperv.c

+20 −4
Original line number Diff line number Diff line
@@ -10,17 +10,22 @@ 
#include "hyperv.h"

#include "kvm_onhyperv.h"



struct kvm_hv_tlb_range {

	u64 start_gfn;

	u64 pages;

};



static int kvm_fill_hv_flush_list_func(struct hv_guest_mapping_flush_list *flush,

		void *data)

{

	struct kvm_tlb_range *range = data;

	struct kvm_hv_tlb_range *range = data;



	return hyperv_fill_flush_guest_mapping_list(flush, range->start_gfn,

			range->pages);

}



static inline int hv_remote_flush_root_tdp(hpa_t root_tdp,

					   struct kvm_tlb_range *range)

					   struct kvm_hv_tlb_range *range)

{

	if (range)

		return hyperv_flush_guest_mapping_range(root_tdp,
@@ -29,7 +34,8 @@ static inline int hv_remote_flush_root_tdp(hpa_t root_tdp, 
		return hyperv_flush_guest_mapping(root_tdp);

}



int hv_flush_remote_tlbs_range(struct kvm *kvm, struct kvm_tlb_range *range)

static int __hv_flush_remote_tlbs_range(struct kvm *kvm,

					struct kvm_hv_tlb_range *range)

{

	struct kvm_arch *kvm_arch = &kvm->arch;

	struct kvm_vcpu *vcpu;
@@ -85,11 +91,21 @@ int hv_flush_remote_tlbs_range(struct kvm *kvm, struct kvm_tlb_range *range) 
	spin_unlock(&kvm_arch->hv_root_tdp_lock);

	return ret;

}



int hv_flush_remote_tlbs_range(struct kvm *kvm, gfn_t start_gfn, gfn_t nr_pages)

{

	struct kvm_hv_tlb_range range = {

		.start_gfn = start_gfn,

		.pages = nr_pages,

	};



	return __hv_flush_remote_tlbs_range(kvm, &range);

}

EXPORT_SYMBOL_GPL(hv_flush_remote_tlbs_range);



int hv_flush_remote_tlbs(struct kvm *kvm)

{

	return hv_flush_remote_tlbs_range(kvm, NULL);

	return __hv_flush_remote_tlbs_range(kvm, NULL);

}

EXPORT_SYMBOL_GPL(hv_flush_remote_tlbs);

arch/x86/kvm/kvm_onhyperv.h

+1 −1
Original line number Diff line number Diff line
@@ -7,7 +7,7 @@ 
#define __ARCH_X86_KVM_KVM_ONHYPERV_H__



#if IS_ENABLED(CONFIG_HYPERV)

int hv_flush_remote_tlbs_range(struct kvm *kvm, struct kvm_tlb_range *range);

int hv_flush_remote_tlbs_range(struct kvm *kvm, gfn_t gfn, gfn_t nr_pages);

int hv_flush_remote_tlbs(struct kvm *kvm);

void hv_track_root_tdp(struct kvm_vcpu *vcpu, hpa_t root_tdp);

#else /* !CONFIG_HYPERV */

arch/x86/kvm/mmu/mmu.c

+2 −6
Original line number Diff line number Diff line
@@ -278,15 +278,11 @@ static inline bool kvm_available_flush_remote_tlbs_range(void) 
void kvm_flush_remote_tlbs_range(struct kvm *kvm, gfn_t start_gfn,

				 gfn_t nr_pages)

{

	struct kvm_tlb_range range;

	int ret = -EOPNOTSUPP;



	range.start_gfn = start_gfn;

	range.pages = nr_pages;



	if (kvm_x86_ops.flush_remote_tlbs_range)

		ret = static_call(kvm_x86_flush_remote_tlbs_range)(kvm, &range);



		ret = static_call(kvm_x86_flush_remote_tlbs_range)(kvm, start_gfn,

								   nr_pages);

	if (ret)

		kvm_flush_remote_tlbs(kvm);

}