KVM: MMU: rename 'pt_write' to 'emulate'

If 'pt_write' is true, we need to emulate the fault. And in later patch, we
need to emulate the fault even though it is not a pt_write event, so rename
it to better fit the meaning

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

arch/x86/kvm/mmu.c

@@ -2023,7 +2023,7 @@ done:
 static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
 			 unsigned pt_access, unsigned pte_access,
 			 int user_fault, int write_fault,
-			 int *ptwrite, int level, gfn_t gfn,
+			 int *emulate, int level, gfn_t gfn,
 			 pfn_t pfn, bool speculative,
 			 bool host_writable)
 {
@@ -2061,7 +2061,7 @@ static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
 		      level, gfn, pfn, speculative, true,
 		      host_writable)) {
 		if (write_fault)
-			*ptwrite = 1;
+			*emulate = 1;
 		kvm_mmu_flush_tlb(vcpu);
 	}
 
@@ -2184,7 +2184,7 @@ static int __direct_map(struct kvm_vcpu *vcpu, gpa_t v, int write,
 {
 	struct kvm_shadow_walk_iterator iterator;
 	struct kvm_mmu_page *sp;
-	int pt_write = 0;
+	int emulate = 0;
 	gfn_t pseudo_gfn;
 
 	for_each_shadow_entry(vcpu, (u64)gfn << PAGE_SHIFT, iterator) {
@@ -2192,7 +2192,7 @@ static int __direct_map(struct kvm_vcpu *vcpu, gpa_t v, int write,
 			unsigned pte_access = ACC_ALL;
 
 			mmu_set_spte(vcpu, iterator.sptep, ACC_ALL, pte_access,
-				     0, write, &pt_write,
+				     0, write, &emulate,
 				     level, gfn, pfn, prefault, map_writable);
 			direct_pte_prefetch(vcpu, iterator.sptep);
 			++vcpu->stat.pf_fixed;
@@ -2220,7 +2220,7 @@ static int __direct_map(struct kvm_vcpu *vcpu, gpa_t v, int write,
 				   | shadow_accessed_mask);
 		}
 	}
-	return pt_write;
+	return emulate;
 }
 
 static void kvm_send_hwpoison_signal(unsigned long address, struct task_struct *tsk)

arch/x86/kvm/paging_tmpl.h

@@ -467,7 +467,7 @@ static void FNAME(pte_prefetch)(struct kvm_vcpu *vcpu, struct guest_walker *gw,
 static u64 *FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr,
 			 struct guest_walker *gw,
 			 int user_fault, int write_fault, int hlevel,
-			 int *ptwrite, pfn_t pfn, bool map_writable,
+			 int *emulate, pfn_t pfn, bool map_writable,
 			 bool prefault)
 {
 	unsigned access = gw->pt_access;
@@ -538,7 +538,7 @@ static u64 *FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr,
 	}
 
 	mmu_set_spte(vcpu, it.sptep, access, gw->pte_access,
-		     user_fault, write_fault, ptwrite, it.level,
+		     user_fault, write_fault, emulate, it.level,
 		     gw->gfn, pfn, prefault, map_writable);
 	FNAME(pte_prefetch)(vcpu, gw, it.sptep);
 
@@ -572,7 +572,7 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr, u32 error_code,
 	int user_fault = error_code & PFERR_USER_MASK;
 	struct guest_walker walker;
 	u64 *sptep;
-	int write_pt = 0;
+	int emulate = 0;
 	int r;
 	pfn_t pfn;
 	int level = PT_PAGE_TABLE_LEVEL;
@@ -633,19 +633,19 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr, u32 error_code,
 	if (!force_pt_level)
 		transparent_hugepage_adjust(vcpu, &walker.gfn, &pfn, &level);
 	sptep = FNAME(fetch)(vcpu, addr, &walker, user_fault, write_fault,
-			     level, &write_pt, pfn, map_writable, prefault);
+			     level, &emulate, pfn, map_writable, prefault);
 	(void)sptep;
-	pgprintk("%s: shadow pte %p %llx ptwrite %d\n", __func__,
-		 sptep, *sptep, write_pt);
+	pgprintk("%s: shadow pte %p %llx emulate %d\n", __func__,
+		 sptep, *sptep, emulate);
 
-	if (!write_pt)
+	if (!emulate)
 		vcpu->arch.last_pt_write_count = 0; /* reset fork detector */
 
 	++vcpu->stat.pf_fixed;
 	trace_kvm_mmu_audit(vcpu, AUDIT_POST_PAGE_FAULT);
 	spin_unlock(&vcpu->kvm->mmu_lock);
 
-	return write_pt;
+	return emulate;
 
 out_unlock:
 	spin_unlock(&vcpu->kvm->mmu_lock);