(resend) Swapping

index a155c2b..74b427f 100644
@@ -409,6 +409,7 @@ struct kvm_memory_slot {
 	unsigned long *rmap;
 	unsigned long *dirty_bitmap;
 	int user_alloc; /* user allocated memory */
+	unsigned long userspace_addr;
 };
 
 struct kvm {

@@ -570,6 +571,7 @@ extern struct page *bad_page;
 int is_error_page(struct page *page);
 gfn_t unalias_gfn(struct kvm *kvm, gfn_t gfn);
 struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn);
+void kvm_release_page(struct page *page);
 int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
 			int len);
 int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len);

161 lines not on this page · raw message

index e6a9b4a..4c91c84 100644
@@ -425,6 +425,8 @@ static void rmap_remove(struct kvm *kvm, u64 *spte)
 	if (!is_rmap_pte(*spte))
 		return;
 	page = page_header(__pa(spte));
+	kvm_release_page(pfn_to_page((*spte & PT64_BASE_ADDR_MASK) >>
+			 PAGE_SHIFT));
 	rmapp = gfn_to_rmap(kvm, page->gfns[spte - page->spt]);
 	if (!*rmapp) {
 		printk(KERN_ERR "rmap_remove: %p %llx 0->BUG\n", spte, *spte);

@@ -907,6 +909,13 @@ static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, hpa_t p)
 			table[index] = p | PT_PRESENT_MASK | PT_WRITABLE_MASK |
 								PT_USER_MASK;
 			rmap_add(vcpu, &table[index], v >> PAGE_SHIFT);
+			if (!is_rmap_pte(table[index])) {
+				struct page *page;
+
+				page = pfn_to_page((v & PT64_BASE_ADDR_MASK)
+						   >> PAGE_SHIFT);
+				kvm_release_page(page);
+			}
 			return 0;
 		}
 

@@ -920,7 +929,12 @@ static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, hpa_t p)
 						     v, level - 1,
 						     1, 3, &table[index]);
 			if (!new_table) {
+				struct page *page;
+
 				pgprintk("nonpaging_map: ENOMEM\n");
+				page = pfn_to_page((v & PT64_BASE_ADDR_MASK)
+						   >> PAGE_SHIFT);
+				kvm_release_page(page);
 				return -ENOMEM;
 			}
 

@@ -1035,8 +1049,11 @@ static int nonpaging_page_fault(struct kvm_vcpu *vcpu, gva_t gva,
 
 	paddr = gpa_to_hpa(vcpu->kvm, addr & PT64_BASE_ADDR_MASK);
 
-	if (is_error_hpa(paddr))
+	if (is_error_hpa(paddr)) {
+		kvm_release_page(pfn_to_page((paddr & PT64_BASE_ADDR_MASK)
+				 >> PAGE_SHIFT));
 		return 1;
+	}
 
 	return nonpaging_map(vcpu, addr & PAGE_MASK, paddr);
 }

@@ -1503,6 +1520,7 @@ static void audit_mappings_page(struct kvm_vcpu *vcpu, u64 page_pte,
 		} else {
 			gpa_t gpa = vcpu->mmu.gva_to_gpa(vcpu, va);
 			hpa_t hpa = gpa_to_hpa(vcpu, gpa);
+			struct page *page;
 
 			if (is_shadow_present_pte(ent)
 			    && (ent & PT64_BASE_ADDR_MASK) != hpa)

@@ -1515,6 +1533,9 @@ static void audit_mappings_page(struct kvm_vcpu *vcpu, u64 page_pte,
 				 && !is_error_hpa(hpa))
 				printk(KERN_ERR "audit: (%s) notrap shadow,"
 				       " valid guest gva %lx\n", audit_msg, va);
+			page = pfn_to_page((paddr & PT64_BASE_ADDR_MASK)
+					   >> PAGE_SHIFT);
+			kvm_release_page(page);
 
 		}
 	}

index 58fd35a..600b1cc 100644
@@ -175,6 +175,7 @@ static int FNAME(walk_addr)(struct guest_walker *walker,
 		walker->inherited_ar &= walker->table[index];
 		table_gfn = (*ptep & PT_BASE_ADDR_MASK) >> PAGE_SHIFT;
 		kunmap_atomic(walker->table, KM_USER0);
+		kvm_release_page(walker->page);
 		walker->page = gfn_to_page(vcpu->kvm, table_gfn);
 		walker->table = kmap_atomic(walker->page, KM_USER0);
 		--walker->level;

@@ -183,8 +184,10 @@ static int FNAME(walk_addr)(struct guest_walker *walker,
 			 walker->level - 1, table_gfn);
 	}
 	walker->pte = *ptep;
-	if (walker->page)
+	if (walker->page) {
 		walker->ptep = NULL;
+		kvm_release_page(walker->page);
+	}
 	if (walker->table)
 		kunmap_atomic(walker->table, KM_USER0);
 	pgprintk("%s: pte %llx\n", __FUNCTION__, (u64)*ptep);

@@ -206,6 +209,8 @@ err:
 		walker->error_code |= PFERR_FETCH_MASK;
 	if (walker->table)
 		kunmap_atomic(walker->table, KM_USER0);
+	if (walker->page)
+		kvm_release_page(walker->page);
 	return 0;
 }
 

@@ -249,6 +254,8 @@ static void FNAME(set_pte_common)(struct kvm_vcpu *vcpu,
 	if (is_error_hpa(paddr)) {
 		set_shadow_pte(shadow_pte,
 			       shadow_trap_nonpresent_pte | PT_SHADOW_IO_MARK);
+		kvm_release_page(pfn_to_page((paddr & PT64_BASE_ADDR_MASK)
+					     >> PAGE_SHIFT));
 		return;
 	}
 

@@ -286,9 +293,20 @@ unshadowed:
 	pgprintk("%s: setting spte %llx\n", __FUNCTION__, spte);
 	set_shadow_pte(shadow_pte, spte);
 	page_header_update_slot(vcpu->kvm, shadow_pte, gaddr);
-	if (!was_rmapped)
+	if (!was_rmapped) {
 		rmap_add(vcpu, shadow_pte, (gaddr & PT64_BASE_ADDR_MASK)
 			 >> PAGE_SHIFT);
+		if (!is_rmap_pte(*shadow_pte)) {
+			struct page *page;
+
+			page = pfn_to_page((paddr & PT64_BASE_ADDR_MASK)
+					   >> PAGE_SHIFT);
+			kvm_release_page(page);
+		}
+	}
+	else
+		kvm_release_page(pfn_to_page((paddr & PT64_BASE_ADDR_MASK)
+				 >> PAGE_SHIFT));
 	if (!ptwrite || !*ptwrite)
 		vcpu->last_pte_updated = shadow_pte;
 }

@@ -512,19 +530,22 @@ static void FNAME(prefetch_page)(struct kvm_vcpu *vcpu,
 {
 	int i;
 	pt_element_t *gpt;
+	struct page *page;
 
 	if (sp->role.metaphysical || PTTYPE == 32) {
 		nonpaging_prefetch_page(vcpu, sp);
 		return;
 	}
 
-	gpt = kmap_atomic(gfn_to_page(vcpu->kvm, sp->gfn), KM_USER0);
+	page = gfn_to_page(vcpu->kvm, sp->gfn);
+	gpt = kmap_atomic(page, KM_USER0);
 	for (i = 0; i < PT64_ENT_PER_PAGE; ++i)
 		if (is_present_pte(gpt[i]))
 			sp->spt[i] = shadow_trap_nonpresent_pte;
 		else
 			sp->spt[i] = shadow_notrap_nonpresent_pte;
 	kunmap_atomic(gpt, KM_USER0);
+	kvm_release_page(page);
 }
 
 #undef pt_element_t