KVM: arm64: Convert to the gfn-based MMU notifier callbacks
authorSean Christopherson <seanjc@google.com>
Fri, 2 Apr 2021 00:56:51 +0000 (17:56 -0700)
committerPaolo Bonzini <pbonzini@redhat.com>
Sat, 17 Apr 2021 12:31:07 +0000 (08:31 -0400)
Move arm64 to the gfn-base MMU notifier APIs, which do the hva->gfn
lookup in common code.

No meaningful functional change intended, though the exact order of
operations is slightly different since the memslot lookups occur before
calling into arch code.

Reviewed-by: Marc Zyngier <maz@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210402005658.3024832-4-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
arch/arm64/include/asm/kvm_host.h
arch/arm64/kvm/mmu.c

index 3a708be..eba448b 100644 (file)
@@ -586,6 +586,7 @@ int __kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu,
                              struct kvm_vcpu_events *events);
 
 #define KVM_ARCH_WANT_MMU_NOTIFIER
+#define KVM_ARCH_WANT_NEW_MMU_NOTIFIER_APIS
 
 void kvm_arm_halt_guest(struct kvm *kvm);
 void kvm_arm_resume_guest(struct kvm *kvm);
index 4b7e1e3..3572823 100644 (file)
@@ -839,7 +839,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
         * gfn_to_pfn_prot (which calls get_user_pages), so that we don't risk
         * the page we just got a reference to gets unmapped before we have a
         * chance to grab the mmu_lock, which ensure that if the page gets
-        * unmapped afterwards, the call to kvm_unmap_hva will take it away
+        * unmapped afterwards, the call to kvm_unmap_gfn will take it away
         * from us again properly. This smp_rmb() interacts with the smp_wmb()
         * in kvm_mmu_notifier_invalidate_<page|range_end>.
         */
@@ -1064,123 +1064,70 @@ out_unlock:
        return ret;
 }
 
-static int handle_hva_to_gpa(struct kvm *kvm,
-                            unsigned long start,
-                            unsigned long end,
-                            int (*handler)(struct kvm *kvm,
-                                           gpa_t gpa, u64 size,
-                                           void *data),
-                            void *data)
+bool kvm_unmap_gfn_range(struct kvm *kvm, struct kvm_gfn_range *range)
 {
-       struct kvm_memslots *slots;
-       struct kvm_memory_slot *memslot;
-       int ret = 0;
-
-       slots = kvm_memslots(kvm);
-
-       /* we only care about the pages that the guest sees */
-       kvm_for_each_memslot(memslot, slots) {
-               unsigned long hva_start, hva_end;
-               gfn_t gpa;
-
-               hva_start = max(start, memslot->userspace_addr);
-               hva_end = min(end, memslot->userspace_addr +
-                                       (memslot->npages << PAGE_SHIFT));
-               if (hva_start >= hva_end)
-                       continue;
-
-               gpa = hva_to_gfn_memslot(hva_start, memslot) << PAGE_SHIFT;
-               ret |= handler(kvm, gpa, (u64)(hva_end - hva_start), data);
-       }
-
-       return ret;
-}
+       if (!kvm->arch.mmu.pgt)
+               return 0;
 
-static int kvm_unmap_hva_handler(struct kvm *kvm, gpa_t gpa, u64 size, void *data)
-{
-       unsigned flags = *(unsigned *)data;
-       bool may_block = flags & MMU_NOTIFIER_RANGE_BLOCKABLE;
+       __unmap_stage2_range(&kvm->arch.mmu, range->start << PAGE_SHIFT,
+                            (range->end - range->start) << PAGE_SHIFT,
+                            range->may_block);
 
-       __unmap_stage2_range(&kvm->arch.mmu, gpa, size, may_block);
        return 0;
 }
 
-int kvm_unmap_hva_range(struct kvm *kvm,
-                       unsigned long start, unsigned long end, unsigned flags)
+bool kvm_set_spte_gfn(struct kvm *kvm, struct kvm_gfn_range *range)
 {
+       kvm_pfn_t pfn = pte_pfn(range->pte);
+
        if (!kvm->arch.mmu.pgt)
                return 0;
 
-       handle_hva_to_gpa(kvm, start, end, &kvm_unmap_hva_handler, &flags);
-       return 0;
-}
-
-static int kvm_set_spte_handler(struct kvm *kvm, gpa_t gpa, u64 size, void *data)
-{
-       kvm_pfn_t *pfn = (kvm_pfn_t *)data;
+       WARN_ON(range->end - range->start != 1);
 
-       WARN_ON(size != PAGE_SIZE);
+       /*
+        * We've moved a page around, probably through CoW, so let's treat it
+        * just like a translation fault and clean the cache to the PoC.
+        */
+       clean_dcache_guest_page(pfn, PAGE_SIZE);
 
        /*
         * The MMU notifiers will have unmapped a huge PMD before calling
-        * ->change_pte() (which in turn calls kvm_set_spte_hva()) and
+        * ->change_pte() (which in turn calls kvm_set_spte_gfn()) and
         * therefore we never need to clear out a huge PMD through this
         * calling path and a memcache is not required.
         */
-       kvm_pgtable_stage2_map(kvm->arch.mmu.pgt, gpa, PAGE_SIZE,
-                              __pfn_to_phys(*pfn), KVM_PGTABLE_PROT_R, NULL);
+       kvm_pgtable_stage2_map(kvm->arch.mmu.pgt, range->start << PAGE_SHIFT,
+                              PAGE_SIZE, __pfn_to_phys(pfn),
+                              KVM_PGTABLE_PROT_R, NULL);
+
        return 0;
 }
 
-int kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte)
+bool kvm_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range)
 {
-       unsigned long end = hva + PAGE_SIZE;
-       kvm_pfn_t pfn = pte_pfn(pte);
+       u64 size = (range->end - range->start) << PAGE_SHIFT;
+       kvm_pte_t kpte;
+       pte_t pte;
 
        if (!kvm->arch.mmu.pgt)
                return 0;
 
-       /*
-        * We've moved a page around, probably through CoW, so let's treat it
-        * just like a translation fault and clean the cache to the PoC.
-        */
-       clean_dcache_guest_page(pfn, PAGE_SIZE);
-       handle_hva_to_gpa(kvm, hva, end, &kvm_set_spte_handler, &pfn);
-       return 0;
-}
-
-static int kvm_age_hva_handler(struct kvm *kvm, gpa_t gpa, u64 size, void *data)
-{
-       pte_t pte;
-       kvm_pte_t kpte;
-
        WARN_ON(size != PAGE_SIZE && size != PMD_SIZE && size != PUD_SIZE);
-       kpte = kvm_pgtable_stage2_mkold(kvm->arch.mmu.pgt, gpa);
+
+       kpte = kvm_pgtable_stage2_mkold(kvm->arch.mmu.pgt,
+                                       range->start << PAGE_SHIFT);
        pte = __pte(kpte);
        return pte_valid(pte) && pte_young(pte);
 }
 
-static int kvm_test_age_hva_handler(struct kvm *kvm, gpa_t gpa, u64 size, void *data)
-{
-       WARN_ON(size != PAGE_SIZE && size != PMD_SIZE && size != PUD_SIZE);
-       return kvm_pgtable_stage2_is_young(kvm->arch.mmu.pgt, gpa);
-}
-
-int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end)
-{
-       if (!kvm->arch.mmu.pgt)
-               return 0;
-
-       return handle_hva_to_gpa(kvm, start, end, kvm_age_hva_handler, NULL);
-}
-
-int kvm_test_age_hva(struct kvm *kvm, unsigned long hva)
+bool kvm_test_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range)
 {
        if (!kvm->arch.mmu.pgt)
                return 0;
 
-       return handle_hva_to_gpa(kvm, hva, hva + PAGE_SIZE,
-                                kvm_test_age_hva_handler, NULL);
+       return kvm_pgtable_stage2_is_young(kvm->arch.mmu.pgt,
+                                          range->start << PAGE_SHIFT);
 }
 
 phys_addr_t kvm_mmu_get_httbr(void)