Commit 73d49df2 authored by Quentin Perret's avatar Quentin Perret Committed by Marc Zyngier
Browse files

KVM: arm64: Add support for stage-2 write-protect in generic page-table 



Add a stage-2 wrprotect() operation to the generic page-table code.

Signed-off-by: default avatarQuentin Perret <qperret@google.com>
Signed-off-by: default avatarWill Deacon <will@kernel.org>
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Reviewed-by: default avatarGavin Shan <gshan@redhat.com>
Cc: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200911132529.19844-13-will@kernel.org
parent ee8efad7

arch/arm64/include/asm/kvm_pgtable.h

+18 −0
Original line number Diff line number Diff line
@@ -186,6 +186,24 @@ int kvm_pgtable_stage2_map(struct kvm_pgtable *pgt, u64 addr, u64 size, 
 */

int kvm_pgtable_stage2_unmap(struct kvm_pgtable *pgt, u64 addr, u64 size);



/**

 * kvm_pgtable_stage2_wrprotect() - Write-protect guest stage-2 address range

 *                                  without TLB invalidation.

 * @pgt:	Page-table structure initialised by kvm_pgtable_stage2_init().

 * @addr:	Intermediate physical address from which to write-protect,

 * @size:	Size of the range.

 *

 * The offset of @addr within a page is ignored and @size is rounded-up to

 * the next page boundary.

 *

 * Note that it is the caller's responsibility to invalidate the TLB after

 * calling this function to ensure that the updated permissions are visible

 * to the CPUs.

 *

 * Return: 0 on success, negative error code on failure.

 */

int kvm_pgtable_stage2_wrprotect(struct kvm_pgtable *pgt, u64 addr, u64 size);



/**

 * kvm_pgtable_stage2_mkyoung() - Set the access flag in a page-table entry.

 * @pgt:	Page-table structure initialised by kvm_pgtable_stage2_init().

arch/arm64/kvm/hyp/pgtable.c

+6 −0
Original line number Diff line number Diff line
@@ -746,6 +746,12 @@ static int stage2_update_leaf_attrs(struct kvm_pgtable *pgt, u64 addr, 
	return 0;

}



int kvm_pgtable_stage2_wrprotect(struct kvm_pgtable *pgt, u64 addr, u64 size)

{

	return stage2_update_leaf_attrs(pgt, addr, size, 0,

					KVM_PTE_LEAF_ATTR_LO_S2_S2AP_W, NULL);

}



kvm_pte_t kvm_pgtable_stage2_mkyoung(struct kvm_pgtable *pgt, u64 addr)

{

	kvm_pte_t pte = 0;