KVM: arm/arm64: Enable Dirty Page logging for ARMv8

This patch enables ARMv8 ditry page logging support. Plugs ARMv8 into generic
layer through Kconfig symbol, and drops earlier ARM64 constraints to enable
logging at architecture layer.

Reviewed-by: Christoffer Dall <[e-mail]>
Signed-off-by: Mario Smarduch <[e-mail]>

arch/arm/include/asm/kvm_host.h

···
 	kvm_call_hyp((void*)hyp_stack_ptr, vector_ptr, pgd_ptr);
 }
 
-/**
- * kvm_flush_remote_tlbs() - flush all VM TLB entries
- * @kvm:	pointer to kvm structure.
- *
- * Interface to HYP function to flush all VM TLB entries without address
- * parameter.
- */
-static inline void kvm_flush_remote_tlbs(struct kvm *kvm)
-{
-	kvm_call_hyp(__kvm_tlb_flush_vmid, kvm);
-}
-
 static inline int kvm_arch_dev_ioctl_check_extension(long ext)
 {
 	return 0;

arch/arm/kvm/arm.c

···
  */
 int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log)
 {
-#ifdef CONFIG_ARM
 	bool is_dirty = false;
 	int r;
 
···
 
 	mutex_unlock(&kvm->slots_lock);
 	return r;
-#else /* arm64 */
-	return -EINVAL;
-#endif
 }
 
 static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm,

arch/arm/kvm/mmu.c

···
 
 static bool memslot_is_logging(struct kvm_memory_slot *memslot)
 {
-#ifdef CONFIG_ARM
 	return memslot->dirty_bitmap && !(memslot->flags & KVM_MEM_READONLY);
-#else
-	return false;
-#endif
+}
+
+/**
+ * kvm_flush_remote_tlbs() - flush all VM TLB entries for v7/8
+ * @kvm:	pointer to kvm structure.
+ *
+ * Interface to HYP function to flush all VM TLB entries
+ */
+void kvm_flush_remote_tlbs(struct kvm *kvm)
+{
+	kvm_call_hyp(__kvm_tlb_flush_vmid, kvm);
 }
 
 static void kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa)
···
 	return !pfn_valid(pfn);
 }
 
-#ifdef CONFIG_ARM
 /**
  * stage2_wp_ptes - write protect PMD range
  * @pmd:	pointer to pmd entry
···
 
 	stage2_wp_range(kvm, start, end);
 }
-#endif
 
 static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
 			  struct kvm_memory_slot *memslot, unsigned long hva,
···
 				   const struct kvm_memory_slot *old,
 				   enum kvm_mr_change change)
 {
-#ifdef CONFIG_ARM
 	/*
 	 * At this point memslot has been committed and there is an
 	 * allocated dirty_bitmap[], dirty pages will be be tracked while the
···
 	 */
 	if (change != KVM_MR_DELETE && mem->flags & KVM_MEM_LOG_DIRTY_PAGES)
 		kvm_mmu_wp_memory_region(kvm, mem->slot);
-#endif
 }
 
 int kvm_arch_prepare_memory_region(struct kvm *kvm,

arch/arm64/kvm/Kconfig

···
 	select PREEMPT_NOTIFIERS
 	select ANON_INODES
 	select HAVE_KVM_CPU_RELAX_INTERCEPT
+	select HAVE_KVM_ARCH_TLB_FLUSH_ALL
 	select KVM_MMIO
 	select KVM_ARM_HOST
 	select KVM_ARM_VGIC
 	select KVM_ARM_TIMER
+	select KVM_GENERIC_DIRTYLOG_READ_PROTECT
 	---help---
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