KVM: rename x86 kvm->arch.n_alloc_mmu_pages

arch.n_alloc_mmu_pages is a poor choice of name. This value truly
means, "the number of pages which _may_ be allocated".  But,
reading the name, "n_alloc_mmu_pages" implies "the number of allocated
mmu pages", which is dead wrong.

It's really the high watermark, so let's give it a name to match:
nr_max_mmu_pages.  This change will make the next few patches
much more obvious and easy to read.

Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com>
Signed-off-by: Tim Pepper <lnxninja@linux.vnet.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

arch/x86/include/asm/kvm_host.h

@@ -369,7 +369,7 @@ struct kvm_vcpu_arch {
 struct kvm_arch {
 	unsigned int n_free_mmu_pages;
 	unsigned int n_requested_mmu_pages;
-	unsigned int n_alloc_mmu_pages;
+	unsigned int n_max_mmu_pages;
 	atomic_t invlpg_counter;
 	struct hlist_head mmu_page_hash[KVM_NUM_MMU_PAGES];
 	/*

arch/x86/kvm/mmu.c

@@ -1696,7 +1696,7 @@ void kvm_mmu_change_mmu_pages(struct kvm *kvm, unsigned int kvm_nr_mmu_pages)
 	int used_pages;
 	LIST_HEAD(invalid_list);
 
-	used_pages = kvm->arch.n_alloc_mmu_pages - kvm_mmu_available_pages(kvm);
+	used_pages = kvm->arch.n_max_mmu_pages - kvm_mmu_available_pages(kvm);
 	used_pages = max(0, used_pages);
 
 	/*
@@ -1721,9 +1721,9 @@ void kvm_mmu_change_mmu_pages(struct kvm *kvm, unsigned int kvm_nr_mmu_pages)
 	}
 	else
 		kvm->arch.n_free_mmu_pages += kvm_nr_mmu_pages
-					 - kvm->arch.n_alloc_mmu_pages;
+					 - kvm->arch.n_max_mmu_pages;
 
-	kvm->arch.n_alloc_mmu_pages = kvm_nr_mmu_pages;
+	kvm->arch.n_max_mmu_pages = kvm_nr_mmu_pages;
 }
 
 static int kvm_mmu_unprotect_page(struct kvm *kvm, gfn_t gfn)
@@ -3141,7 +3141,7 @@ static int mmu_shrink(struct shrinker *shrink, int nr_to_scan, gfp_t gfp_mask)
 
 		idx = srcu_read_lock(&kvm->srcu);
 		spin_lock(&kvm->mmu_lock);
-		npages = kvm->arch.n_alloc_mmu_pages -
+		npages = kvm->arch.n_max_mmu_pages -
 			 kvm_mmu_available_pages(kvm);
 		cache_count += npages;
 		if (!kvm_freed && nr_to_scan > 0 && npages > 0) {

arch/x86/kvm/x86.c

@@ -2759,7 +2759,7 @@ static int kvm_vm_ioctl_set_nr_mmu_pages(struct kvm *kvm,
 
 static int kvm_vm_ioctl_get_nr_mmu_pages(struct kvm *kvm)
 {
-	return kvm->arch.n_alloc_mmu_pages;
+	return kvm->arch.n_max_mmu_pages;
 }
 
 static int kvm_vm_ioctl_get_irqchip(struct kvm *kvm, struct kvm_irqchip *chip)