KVM: x86/mmu: Use gfn_t in kvm_flush_remote_tlbs_range()

Use gfn_t instead of u64 for kvm_flush_remote_tlbs_range()'s parameters,
since gfn_t is the standard type for GFNs throughout KVM.

Opportunistically rename pages to nr_pages to make its role even more
obvious.

No functional change intended.

Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20230126184025.2294823-6-dmatlack@google.com
[sean: convert pages to gfn_t too, and rename]
Signed-off-by: Sean Christopherson <seanjc@google.com>

Author: dmatlack

arch/x86/kvm/mmu/mmu.c

@@ -261,13 +261,14 @@ static inline bool kvm_available_flush_tlb_with_range(void)
 	return kvm_x86_ops.tlb_remote_flush_with_range;
 }
 
-void kvm_flush_remote_tlbs_range(struct kvm *kvm, u64 start_gfn, u64 pages)
+void kvm_flush_remote_tlbs_range(struct kvm *kvm, gfn_t start_gfn,
+				 gfn_t nr_pages)
 {
 	struct kvm_tlb_range range;
 	int ret = -EOPNOTSUPP;
 
 	range.start_gfn = start_gfn;
-	range.pages = pages;
+	range.pages = nr_pages;
 
 	if (kvm_x86_ops.tlb_remote_flush_with_range)
 		ret = static_call(kvm_x86_tlb_remote_flush_with_range)(kvm, &range);

arch/x86/kvm/mmu/mmu_internal.h

@@ -170,7 +170,8 @@ bool kvm_mmu_slot_gfn_write_protect(struct kvm *kvm,
 				    struct kvm_memory_slot *slot, u64 gfn,
 				    int min_level);
 
-void kvm_flush_remote_tlbs_range(struct kvm *kvm, u64 start_gfn, u64 pages);
+void kvm_flush_remote_tlbs_range(struct kvm *kvm, gfn_t start_gfn,
+				 gfn_t nr_pages);
 
 /* Flush the given page (huge or not) of guest memory. */
 static inline void kvm_flush_remote_tlbs_gfn(struct kvm *kvm, gfn_t gfn, int level)