KVM: x86: Use standard mmu_notifier invalidate hooks for APIC access page

Now that KVM honors past and in-progress mmu_notifier invalidations when
reloading the APIC-access page, use KVM's "standard" invalidation hooks
to trigger a reload and delete the one-off usage of invalidate_range().

Aside from eliminating one-off code in KVM, dropping KVM's use of
invalidate_range() will allow common mmu_notifier to redefine the API to
be more strictly focused on invalidating secondary TLBs that share the
primary MMU's page tables.

Suggested-by: Jason Gunthorpe <jgg@nvidia.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Alistair Popple <apopple@nvidia.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Link: https://lore.kernel.org/r/20230602011518.787006-3-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index c8961f4..01a11ce 100644 (file)
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -1600,6 +1600,9 @@ bool kvm_unmap_gfn_range(struct kvm *kvm, struct kvm_gfn_range *range)
        if (tdp_mmu_enabled)
                flush = kvm_tdp_mmu_unmap_gfn_range(kvm, range, flush);
 
+       if (range->slot->id == APIC_ACCESS_PAGE_PRIVATE_MEMSLOT)
+               kvm_make_all_cpus_request(kvm, KVM_REQ_APIC_PAGE_RELOAD);
+
        return flush;
 }
 

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index c0778ca..f962b7e 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -10435,20 +10435,6 @@ static void vcpu_load_eoi_exitmap(struct kvm_vcpu *vcpu)
                vcpu, (u64 *)vcpu->arch.ioapic_handled_vectors);
 }
 
-void kvm_arch_mmu_notifier_invalidate_range(struct kvm *kvm,
-                                           unsigned long start, unsigned long end)
-{
-       unsigned long apic_address;
-
-       /*
-        * The physical address of apic access page is stored in the VMCS.
-        * Update it when it becomes invalid.
-        */
-       apic_address = gfn_to_hva(kvm, APIC_DEFAULT_PHYS_BASE >> PAGE_SHIFT);
-       if (start <= apic_address && apic_address < end)
-               kvm_make_all_cpus_request(kvm, KVM_REQ_APIC_PAGE_RELOAD);
-}
-
 void kvm_arch_guest_memory_reclaimed(struct kvm *kvm)
 {
        static_call_cond(kvm_x86_guest_memory_reclaimed)(kvm);

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 0e571e9..cb66f41 100644 (file)
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -2237,9 +2237,6 @@ static inline long kvm_arch_vcpu_async_ioctl(struct file *filp,
 }
 #endif /* CONFIG_HAVE_KVM_VCPU_ASYNC_IOCTL */
 
-void kvm_arch_mmu_notifier_invalidate_range(struct kvm *kvm,
-                                           unsigned long start, unsigned long end);
-
 void kvm_arch_guest_memory_reclaimed(struct kvm *kvm);
 
 #ifdef CONFIG_HAVE_KVM_VCPU_RUN_PID_CHANGE

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 479802a..f3c7c3c 100644 (file)
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -154,11 +154,6 @@ static unsigned long long kvm_active_vms;
 
 static DEFINE_PER_CPU(cpumask_var_t, cpu_kick_mask);
 
-__weak void kvm_arch_mmu_notifier_invalidate_range(struct kvm *kvm,
-                                                  unsigned long start, unsigned long end)
-{
-}
-
 __weak void kvm_arch_guest_memory_reclaimed(struct kvm *kvm)
 {
 }
@@ -521,18 +516,6 @@ static inline struct kvm *mmu_notifier_to_kvm(struct mmu_notifier *mn)
        return container_of(mn, struct kvm, mmu_notifier);
 }
 
-static void kvm_mmu_notifier_invalidate_range(struct mmu_notifier *mn,
-                                             struct mm_struct *mm,
-                                             unsigned long start, unsigned long end)
-{
-       struct kvm *kvm = mmu_notifier_to_kvm(mn);
-       int idx;
-
-       idx = srcu_read_lock(&kvm->srcu);
-       kvm_arch_mmu_notifier_invalidate_range(kvm, start, end);
-       srcu_read_unlock(&kvm->srcu, idx);
-}
-
 typedef bool (*hva_handler_t)(struct kvm *kvm, struct kvm_gfn_range *range);
 
 typedef void (*on_lock_fn_t)(struct kvm *kvm, unsigned long start,
@@ -892,7 +875,6 @@ static void kvm_mmu_notifier_release(struct mmu_notifier *mn,
 }
 
 static const struct mmu_notifier_ops kvm_mmu_notifier_ops = {
-       .invalidate_range       = kvm_mmu_notifier_invalidate_range,
        .invalidate_range_start = kvm_mmu_notifier_invalidate_range_start,
        .invalidate_range_end   = kvm_mmu_notifier_invalidate_range_end,
        .clear_flush_young      = kvm_mmu_notifier_clear_flush_young,