kvm: libkvm: substitute is_allocated_mem with more general is_containing_region

is_allocated_mem is a function that checks if every relevant aspect of the
memory slot match (start and size). Replace it with a more generic function
that checks if a memory region is totally contained into another. The former
case is also covered.

Signed-off-by: Glauber Costa <glommer@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

2 files changed, 14 insertions, 24 deletions

diff --git a/libkvm/libkvm.c b/libkvm/libkvm.c
index c2610530..11a95292 100644
--- a/libkvm/libkvm.c
+++ b/libkvm/libkvm.c
@@ -125,17 +125,27 @@ int get_slot(unsigned long phys_addr)
 	return -1;
 }
 
-int get_intersecting_slot(unsigned long phys_addr)
+/* Returns -1 if this slot is not totally contained on any other,
+ * and the number of the slot otherwise */
+int get_container_slot(uint64_t phys_addr, unsigned long size)
 {
 	int i;
 
 	for (i = 0; i < KVM_MAX_NUM_MEM_REGIONS ; ++i)
-		if (slots[i].len && slots[i].phys_addr < phys_addr &&
-		    (slots[i].phys_addr + slots[i].len) > phys_addr)
+		if (slots[i].len && slots[i].phys_addr <= phys_addr &&
+		    (slots[i].phys_addr + slots[i].len) >= phys_addr + size)
 			return i;
 	return -1;
 }
 
+int kvm_is_containing_region(kvm_context_t kvm, unsigned long phys_addr, unsigned long size)
+{
+	int slot = get_container_slot(phys_addr, size);
+	if (slot == -1)
+		return 0;
+	return 1;
+}
+
 /* 
  * dirty pages logging control 
  */
@@ -421,24 +431,6 @@ void *kvm_create_phys_mem(kvm_context_t kvm, unsigned long phys_start,
         return ptr;
 }
 
-int kvm_is_intersecting_mem(kvm_context_t kvm, unsigned long phys_start)
-{
-	return get_intersecting_slot(phys_start) != -1;
-}
-
-int kvm_is_allocated_mem(kvm_context_t kvm, unsigned long phys_start,
-			 unsigned long len)
-{
-	int slot;
-
-	slot = get_slot(phys_start);
-	if (slot == -1)
-		return 0;
-	if (slots[slot].len == len)
-		return 1;
-	return 0;
-}
-
 int kvm_register_phys_mem(kvm_context_t kvm,
 			  unsigned long phys_start, void *userspace_addr,
 			  unsigned long len, int log)
diff --git a/libkvm/libkvm.h b/libkvm/libkvm.h
index 77fd903f..cb77c6cf 100644
--- a/libkvm/libkvm.h
+++ b/libkvm/libkvm.h
@@ -454,9 +454,7 @@ void *kvm_create_phys_mem(kvm_context_t, unsigned long phys_start,
 			  unsigned long len, int log, int writable);
 void kvm_destroy_phys_mem(kvm_context_t, unsigned long phys_start, 
 			  unsigned long len);
-int kvm_is_intersecting_mem(kvm_context_t kvm, unsigned long phys_start);
-int kvm_is_allocated_mem(kvm_context_t kvm, unsigned long phys_start,
-			 unsigned long len);
+int kvm_is_containing_region(kvm_context_t kvm, unsigned long phys_start, unsigned long size);
 int kvm_register_phys_mem(kvm_context_t kvm,
 			unsigned long phys_start, void *userspace_addr,
 			unsigned long len, int log);