KVM: arm64: Pass walk flags to kvm_pgtable_stage2_relax_perms

kvm_pgtable_stage2_relax_perms currently assumes that it is being called
from a 'shared' walker, which will not be true once called from pKVM. To
allow for the re-use of that function, make the walk flags one of its
parameters.

Tested-by: Fuad Tabba <tabba@google.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Quentin Perret <qperret@google.com>
Link: https://lore.kernel.org/r/20241218194059.3670226-7-qperret@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>

diff --git a/arch/arm64/include/asm/kvm_pgtable.h b/arch/arm64/include/asm/kvm_pgtable.h
index 38b7ec1c86141436a9cf698197647a72c042f46f..c2f4149283ef46b08c6631cae7081380f7b9dfc1 100644 (file)
--- a/arch/arm64/include/asm/kvm_pgtable.h
+++ b/arch/arm64/include/asm/kvm_pgtable.h
@@ -707,6 +707,7 @@ bool kvm_pgtable_stage2_test_clear_young(struct kvm_pgtable *pgt, u64 addr,
  * @pgt:       Page-table structure initialised by kvm_pgtable_stage2_init*().
  * @addr:      Intermediate physical address to identify the page-table entry.
  * @prot:      Additional permissions to grant for the mapping.
+ * @flags:     Flags to control the page-table walk (ex. a shared walk)
  *
  * The offset of @addr within a page is ignored.
  *
@@ -719,7 +720,8 @@ bool kvm_pgtable_stage2_test_clear_young(struct kvm_pgtable *pgt, u64 addr,
  * Return: 0 on success, negative error code on failure.
  */
 int kvm_pgtable_stage2_relax_perms(struct kvm_pgtable *pgt, u64 addr,
-                                  enum kvm_pgtable_prot prot);
+                                  enum kvm_pgtable_prot prot,
+                                  enum kvm_pgtable_walk_flags flags);
 
 /**
  * kvm_pgtable_stage2_flush_range() - Clean and invalidate data cache to Point

diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c
index 0470aedb4bf440d0086ebd69b42397ae90cd8d25..b7a3b536323551685109e0d213e7ab33d843bd11 100644 (file)
--- a/arch/arm64/kvm/hyp/pgtable.c
+++ b/arch/arm64/kvm/hyp/pgtable.c
@@ -1307,7 +1307,7 @@ bool kvm_pgtable_stage2_test_clear_young(struct kvm_pgtable *pgt, u64 addr,
 }
 
 int kvm_pgtable_stage2_relax_perms(struct kvm_pgtable *pgt, u64 addr,
-                                  enum kvm_pgtable_prot prot)
+                                  enum kvm_pgtable_prot prot, enum kvm_pgtable_walk_flags flags)
 {
        int ret;
        s8 level;
@@ -1325,9 +1325,7 @@ int kvm_pgtable_stage2_relax_perms(struct kvm_pgtable *pgt, u64 addr,
        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, &level,
-                                      KVM_PGTABLE_WALK_HANDLE_FAULT |
-                                      KVM_PGTABLE_WALK_SHARED);
+       ret = stage2_update_leaf_attrs(pgt, addr, 1, set, clr, NULL, &level, flags);
        if (!ret || ret == -EAGAIN)
                kvm_call_hyp(__kvm_tlb_flush_vmid_ipa_nsh, pgt->mmu, addr, level);
        return ret;

diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index a2339b76c826f49d2a9b721a0be964c6b34f5101..641e4fec16593cb12b9db3b15e04b1deea98c87e 100644 (file)
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -1452,6 +1452,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
        enum kvm_pgtable_prot prot = KVM_PGTABLE_PROT_R;
        struct kvm_pgtable *pgt;
        struct page *page;
+       enum kvm_pgtable_walk_flags flags = KVM_PGTABLE_WALK_HANDLE_FAULT | KVM_PGTABLE_WALK_SHARED;
 
        if (fault_is_perm)
                fault_granule = kvm_vcpu_trap_get_perm_fault_granule(vcpu);
@@ -1695,13 +1696,11 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
                 * PTE, which will be preserved.
                 */
                prot &= ~KVM_NV_GUEST_MAP_SZ;
-               ret = kvm_pgtable_stage2_relax_perms(pgt, fault_ipa, prot);
+               ret = kvm_pgtable_stage2_relax_perms(pgt, fault_ipa, prot, flags);
        } else {
                ret = kvm_pgtable_stage2_map(pgt, fault_ipa, vma_pagesize,
                                             __pfn_to_phys(pfn), prot,
-                                            memcache,
-                                            KVM_PGTABLE_WALK_HANDLE_FAULT |
-                                            KVM_PGTABLE_WALK_SHARED);
+                                            memcache, flags);
        }
 
 out_unlock: