Commit ec14c272 authored by Christoffer Dall's avatar Christoffer Dall Committed by Oliver Upton
Browse files

KVM: arm64: nv: Unmap/flush shadow stage 2 page tables 



Unmap/flush shadow stage 2 page tables for the nested VMs as well as the
stage 2 page table for the guest hypervisor.

Note: A bunch of the code in mmu.c relating to MMU notifiers is
currently dealt with in an extremely abrupt way, for example by clearing
out an entire shadow stage-2 table. This will be handled in a more
efficient way using the reverse mapping feature in a later version of
the patch series.

Signed-off-by: default avatarChristoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: default avatarJintack Lim <jintack.lim@linaro.org>
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20240614144552.2773592-5-maz@kernel.org


Signed-off-by: default avatarOliver Upton <oliver.upton@linux.dev>
parent fd276e71

arch/arm64/include/asm/kvm_mmu.h

+2 −0
Original line number Diff line number Diff line
@@ -167,6 +167,8 @@ int create_hyp_stack(phys_addr_t phys_addr, unsigned long *haddr); 
void __init free_hyp_pgds(void);



void kvm_stage2_unmap_range(struct kvm_s2_mmu *mmu, phys_addr_t start, u64 size);

void kvm_stage2_flush_range(struct kvm_s2_mmu *mmu, phys_addr_t addr, phys_addr_t end);

void kvm_stage2_wp_range(struct kvm_s2_mmu *mmu, phys_addr_t addr, phys_addr_t end);



void stage2_unmap_vm(struct kvm *kvm);

int kvm_init_stage2_mmu(struct kvm *kvm, struct kvm_s2_mmu *mmu, unsigned long type);

arch/arm64/include/asm/kvm_nested.h

+3 −0
Original line number Diff line number Diff line
@@ -113,6 +113,9 @@ extern int kvm_walk_nested_s2(struct kvm_vcpu *vcpu, phys_addr_t gipa, 
extern int kvm_s2_handle_perm_fault(struct kvm_vcpu *vcpu,

				    struct kvm_s2_trans *trans);

extern int kvm_inject_s2_fault(struct kvm_vcpu *vcpu, u64 esr_el2);

extern void kvm_nested_s2_wp(struct kvm *kvm);

extern void kvm_nested_s2_unmap(struct kvm *kvm);

extern void kvm_nested_s2_flush(struct kvm *kvm);



int kvm_init_nv_sysregs(struct kvm *kvm);

arch/arm64/kvm/mmu.c

+23 −5
Original line number Diff line number Diff line
@@ -333,13 +333,18 @@ void kvm_stage2_unmap_range(struct kvm_s2_mmu *mmu, phys_addr_t start, u64 size) 
	__unmap_stage2_range(mmu, start, size, true);

}



void kvm_stage2_flush_range(struct kvm_s2_mmu *mmu, phys_addr_t addr, phys_addr_t end)

{

	stage2_apply_range_resched(mmu, addr, end, kvm_pgtable_stage2_flush);

}



static void stage2_flush_memslot(struct kvm *kvm,

				 struct kvm_memory_slot *memslot)

{

	phys_addr_t addr = memslot->base_gfn << PAGE_SHIFT;

	phys_addr_t end = addr + PAGE_SIZE * memslot->npages;



	stage2_apply_range_resched(&kvm->arch.mmu, addr, end, kvm_pgtable_stage2_flush);

	kvm_stage2_flush_range(&kvm->arch.mmu, addr, end);

}



/**
@@ -362,6 +367,8 @@ static void stage2_flush_vm(struct kvm *kvm) 
	kvm_for_each_memslot(memslot, bkt, slots)

		stage2_flush_memslot(kvm, memslot);



	kvm_nested_s2_flush(kvm);



	write_unlock(&kvm->mmu_lock);

	srcu_read_unlock(&kvm->srcu, idx);

}
@@ -1035,6 +1042,8 @@ void stage2_unmap_vm(struct kvm *kvm) 
	kvm_for_each_memslot(memslot, bkt, slots)

		stage2_unmap_memslot(kvm, memslot);



	kvm_nested_s2_unmap(kvm);



	write_unlock(&kvm->mmu_lock);

	mmap_read_unlock(current->mm);

	srcu_read_unlock(&kvm->srcu, idx);
@@ -1134,12 +1143,12 @@ int kvm_phys_addr_ioremap(struct kvm *kvm, phys_addr_t guest_ipa, 
}



/**

 * stage2_wp_range() - write protect stage2 memory region range

 * kvm_stage2_wp_range() - write protect stage2 memory region range

 * @mmu:        The KVM stage-2 MMU pointer

 * @addr:	Start address of range

 * @end:	End address of range

 */

static void stage2_wp_range(struct kvm_s2_mmu *mmu, phys_addr_t addr, phys_addr_t end)

void kvm_stage2_wp_range(struct kvm_s2_mmu *mmu, phys_addr_t addr, phys_addr_t end)

{

	stage2_apply_range_resched(mmu, addr, end, kvm_pgtable_stage2_wrprotect);

}
@@ -1170,7 +1179,8 @@ static void kvm_mmu_wp_memory_region(struct kvm *kvm, int slot) 
	end = (memslot->base_gfn + memslot->npages) << PAGE_SHIFT;



	write_lock(&kvm->mmu_lock);

	stage2_wp_range(&kvm->arch.mmu, start, end);

	kvm_stage2_wp_range(&kvm->arch.mmu, start, end);

	kvm_nested_s2_wp(kvm);

	write_unlock(&kvm->mmu_lock);

	kvm_flush_remote_tlbs_memslot(kvm, memslot);

}
@@ -1224,7 +1234,7 @@ void kvm_arch_mmu_enable_log_dirty_pt_masked(struct kvm *kvm, 


	lockdep_assert_held_write(&kvm->mmu_lock);



	stage2_wp_range(&kvm->arch.mmu, start, end);

	kvm_stage2_wp_range(&kvm->arch.mmu, start, end);



	/*

	 * Eager-splitting is done when manual-protect is set.  We
@@ -1236,6 +1246,8 @@ void kvm_arch_mmu_enable_log_dirty_pt_masked(struct kvm *kvm, 
	 */

	if (kvm_dirty_log_manual_protect_and_init_set(kvm))

		kvm_mmu_split_huge_pages(kvm, start, end);



	kvm_nested_s2_wp(kvm);

}



static void kvm_send_hwpoison_signal(unsigned long address, short lsb)
@@ -1878,6 +1890,7 @@ bool kvm_unmap_gfn_range(struct kvm *kvm, struct kvm_gfn_range *range) 
			     (range->end - range->start) << PAGE_SHIFT,

			     range->may_block);



	kvm_nested_s2_unmap(kvm);

	return false;

}
@@ -1891,6 +1904,10 @@ bool kvm_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range) 
	return kvm_pgtable_stage2_test_clear_young(kvm->arch.mmu.pgt,

						   range->start << PAGE_SHIFT,

						   size, true);

	/*

	 * TODO: Handle nested_mmu structures here using the reverse mapping in

	 * a later version of patch series.

	 */

}



bool kvm_test_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range)
@@ -2141,6 +2158,7 @@ void kvm_arch_flush_shadow_memslot(struct kvm *kvm, 


	write_lock(&kvm->mmu_lock);

	kvm_stage2_unmap_range(&kvm->arch.mmu, gpa, size);

	kvm_nested_s2_unmap(kvm);

	write_unlock(&kvm->mmu_lock);

}

arch/arm64/kvm/nested.c

+42 −0
Original line number Diff line number Diff line
@@ -527,6 +527,48 @@ int kvm_inject_s2_fault(struct kvm_vcpu *vcpu, u64 esr_el2) 
	return kvm_inject_nested_sync(vcpu, esr_el2);

}



void kvm_nested_s2_wp(struct kvm *kvm)

{

	int i;



	lockdep_assert_held_write(&kvm->mmu_lock);



	for (i = 0; i < kvm->arch.nested_mmus_size; i++) {

		struct kvm_s2_mmu *mmu = &kvm->arch.nested_mmus[i];



		if (kvm_s2_mmu_valid(mmu))

			kvm_stage2_wp_range(mmu, 0, kvm_phys_size(mmu));

	}

}



void kvm_nested_s2_unmap(struct kvm *kvm)

{

	int i;



	lockdep_assert_held_write(&kvm->mmu_lock);



	for (i = 0; i < kvm->arch.nested_mmus_size; i++) {

		struct kvm_s2_mmu *mmu = &kvm->arch.nested_mmus[i];



		if (kvm_s2_mmu_valid(mmu))

			kvm_stage2_unmap_range(mmu, 0, kvm_phys_size(mmu));

	}

}



void kvm_nested_s2_flush(struct kvm *kvm)

{

	int i;



	lockdep_assert_held_write(&kvm->mmu_lock);



	for (i = 0; i < kvm->arch.nested_mmus_size; i++) {

		struct kvm_s2_mmu *mmu = &kvm->arch.nested_mmus[i];



		if (kvm_s2_mmu_valid(mmu))

			kvm_stage2_flush_range(mmu, 0, kvm_phys_size(mmu));

	}

}



void kvm_arch_flush_shadow_all(struct kvm *kvm)

{

	int i;