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authorWill Deacon <will@kernel.org>2020-09-11 16:25:24 +0300
committerMarc Zyngier <maz@kernel.org>2020-09-11 17:51:15 +0300
commitadcd4e23291e67575be0c8b08eed04fbe7fd9e77 (patch)
treed686875c1a9320c694c212a24073adf15177da9c /arch/arm64/kvm/hyp/pgtable.c
parent8d5207bef6913b5fac91cb58e509711e406c160d (diff)
downloadlinux-adcd4e23291e67575be0c8b08eed04fbe7fd9e77.tar.xz
KVM: arm64: Add support for relaxing stage-2 perms in generic page-table code
Add support for relaxing the permissions of a stage-2 mapping (i.e. adding additional permissions) to the generic page-table code. Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Gavin Shan <gshan@redhat.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Quentin Perret <qperret@google.com> Link: https://lore.kernel.org/r/20200911132529.19844-17-will@kernel.org
Diffstat (limited to 'arch/arm64/kvm/hyp/pgtable.c')
-rw-r--r--arch/arm64/kvm/hyp/pgtable.c20
1 files changed, 20 insertions, 0 deletions
diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c
index d382756a527c..603d6b415337 100644
--- a/arch/arm64/kvm/hyp/pgtable.c
+++ b/arch/arm64/kvm/hyp/pgtable.c
@@ -782,6 +782,26 @@ bool kvm_pgtable_stage2_is_young(struct kvm_pgtable *pgt, u64 addr)
return pte & KVM_PTE_LEAF_ATTR_LO_S2_AF;
}
+int kvm_pgtable_stage2_relax_perms(struct kvm_pgtable *pgt, u64 addr,
+ enum kvm_pgtable_prot prot)
+{
+ int ret;
+ kvm_pte_t set = 0, clr = 0;
+
+ if (prot & KVM_PGTABLE_PROT_R)
+ set |= KVM_PTE_LEAF_ATTR_LO_S2_S2AP_R;
+
+ if (prot & KVM_PGTABLE_PROT_W)
+ set |= KVM_PTE_LEAF_ATTR_LO_S2_S2AP_W;
+
+ if (prot & KVM_PGTABLE_PROT_X)
+ clr |= KVM_PTE_LEAF_ATTR_HI_S2_XN;
+
+ ret = stage2_update_leaf_attrs(pgt, addr, 1, set, clr, NULL);
+ kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, pgt->mmu, addr, 0);
+ return ret;
+}
+
static int stage2_flush_walker(u64 addr, u64 end, u32 level, kvm_pte_t *ptep,
enum kvm_pgtable_walk_flags flag,
void * const arg)