Commit d4788996 authored by David Matlack's avatar David Matlack Committed by Marc Zyngier
Browse files

KVM: Allow range-based TLB invalidation from common code 



Make kvm_flush_remote_tlbs_range() visible in common code and create a
default implementation that just invalidates the whole TLB.

This paves the way for several future features/cleanups:

 - Introduction of range-based TLBI on ARM.
 - Eliminating kvm_arch_flush_remote_tlbs_memslot()
 - Moving the KVM/x86 TDP MMU to common code.

No functional change intended.

Signed-off-by: default avatarDavid Matlack <dmatlack@google.com>
Signed-off-by: default avatarRaghavendra Rao Ananta <rananta@google.com>
Reviewed-by: default avatarGavin Shan <gshan@redhat.com>
Reviewed-by: default avatarShaoqin Huang <shahuang@redhat.com>
Reviewed-by: default avatarAnup Patel <anup@brainfault.org>
Acked-by: default avatarSean Christopherson <seanjc@google.com>
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230811045127.3308641-6-rananta@google.com
parent eddd2148

arch/x86/include/asm/kvm_host.h

+2 −0
Original line number Diff line number Diff line
@@ -1804,6 +1804,8 @@ static inline int kvm_arch_flush_remote_tlbs(struct kvm *kvm) 
		return -ENOTSUPP;

}



#define __KVM_HAVE_ARCH_FLUSH_REMOTE_TLBS_RANGE



#define kvm_arch_pmi_in_guest(vcpu) \

	((vcpu) && (vcpu)->arch.handling_intr_from_guest)

arch/x86/kvm/mmu/mmu.c

+4 −8
Original line number Diff line number Diff line
@@ -278,16 +278,12 @@ static inline bool kvm_available_flush_remote_tlbs_range(void) 
	return kvm_x86_ops.flush_remote_tlbs_range;

}



void kvm_flush_remote_tlbs_range(struct kvm *kvm, gfn_t start_gfn,

				 gfn_t nr_pages)

int kvm_arch_flush_remote_tlbs_range(struct kvm *kvm, gfn_t gfn, u64 nr_pages)

{

	int ret = -EOPNOTSUPP;

	if (!kvm_x86_ops.flush_remote_tlbs_range)

		return -EOPNOTSUPP;



	if (kvm_x86_ops.flush_remote_tlbs_range)

		ret = static_call(kvm_x86_flush_remote_tlbs_range)(kvm, start_gfn,

								   nr_pages);

	if (ret)

		kvm_flush_remote_tlbs(kvm);

	return static_call(kvm_x86_flush_remote_tlbs_range)(kvm, gfn, nr_pages);

}



static gfn_t kvm_mmu_page_get_gfn(struct kvm_mmu_page *sp, int index);

arch/x86/kvm/mmu/mmu_internal.h

+0 −3
Original line number Diff line number Diff line
@@ -170,9 +170,6 @@ bool kvm_mmu_slot_gfn_write_protect(struct kvm *kvm, 
				    struct kvm_memory_slot *slot, u64 gfn,

				    int min_level);



void kvm_flush_remote_tlbs_range(struct kvm *kvm, gfn_t start_gfn,

				 gfn_t nr_pages);



/* Flush the given page (huge or not) of guest memory. */

static inline void kvm_flush_remote_tlbs_gfn(struct kvm *kvm, gfn_t gfn, int level)

{

include/linux/kvm_host.h

+11 −0
Original line number Diff line number Diff line
@@ -1359,6 +1359,7 @@ int kvm_vcpu_yield_to(struct kvm_vcpu *target); 
void kvm_vcpu_on_spin(struct kvm_vcpu *vcpu, bool yield_to_kernel_mode);



void kvm_flush_remote_tlbs(struct kvm *kvm);

void kvm_flush_remote_tlbs_range(struct kvm *kvm, gfn_t gfn, u64 nr_pages);



#ifdef KVM_ARCH_NR_OBJS_PER_MEMORY_CACHE

int kvm_mmu_topup_memory_cache(struct kvm_mmu_memory_cache *mc, int min);
@@ -1488,6 +1489,16 @@ static inline int kvm_arch_flush_remote_tlbs(struct kvm *kvm) 
int kvm_arch_flush_remote_tlbs(struct kvm *kvm);

#endif



#ifndef __KVM_HAVE_ARCH_FLUSH_REMOTE_TLBS_RANGE

static inline int kvm_arch_flush_remote_tlbs_range(struct kvm *kvm,

						    gfn_t gfn, u64 nr_pages)

{

	return -EOPNOTSUPP;

}

#else

int kvm_arch_flush_remote_tlbs_range(struct kvm *kvm, gfn_t gfn, u64 nr_pages);

#endif



#ifdef __KVM_HAVE_ARCH_NONCOHERENT_DMA

void kvm_arch_register_noncoherent_dma(struct kvm *kvm);

void kvm_arch_unregister_noncoherent_dma(struct kvm *kvm);

virt/kvm/kvm_main.c

+13 −0
Original line number Diff line number Diff line
@@ -366,6 +366,19 @@ void kvm_flush_remote_tlbs(struct kvm *kvm) 
}

EXPORT_SYMBOL_GPL(kvm_flush_remote_tlbs);



void kvm_flush_remote_tlbs_range(struct kvm *kvm, gfn_t gfn, u64 nr_pages)

{

	if (!kvm_arch_flush_remote_tlbs_range(kvm, gfn, nr_pages))

		return;



	/*

	 * Fall back to a flushing entire TLBs if the architecture range-based

	 * TLB invalidation is unsupported or can't be performed for whatever

	 * reason.

	 */

	kvm_flush_remote_tlbs(kvm);

}



static void kvm_flush_shadow_all(struct kvm *kvm)

{

	kvm_arch_flush_shadow_all(kvm);