KVM: introduce wrapper functions for creating/destroying dirty bitmaps
This makes it easy to change the way of allocating/freeing dirty bitmaps.
Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 880370c..0021c28 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -444,6 +444,15 @@
return ERR_PTR(r);
}
+static void kvm_destroy_dirty_bitmap(struct kvm_memory_slot *memslot)
+{
+ if (!memslot->dirty_bitmap)
+ return;
+
+ vfree(memslot->dirty_bitmap);
+ memslot->dirty_bitmap = NULL;
+}
+
/*
* Free any memory in @free but not in @dont.
*/
@@ -456,7 +465,7 @@
vfree(free->rmap);
if (!dont || free->dirty_bitmap != dont->dirty_bitmap)
- vfree(free->dirty_bitmap);
+ kvm_destroy_dirty_bitmap(free);
for (i = 0; i < KVM_NR_PAGE_SIZES - 1; ++i) {
@@ -467,7 +476,6 @@
}
free->npages = 0;
- free->dirty_bitmap = NULL;
free->rmap = NULL;
}
@@ -529,6 +537,18 @@
return 0;
}
+static int kvm_create_dirty_bitmap(struct kvm_memory_slot *memslot)
+{
+ unsigned long dirty_bytes = kvm_dirty_bitmap_bytes(memslot);
+
+ memslot->dirty_bitmap = vmalloc(dirty_bytes);
+ if (!memslot->dirty_bitmap)
+ return -ENOMEM;
+
+ memset(memslot->dirty_bitmap, 0, dirty_bytes);
+ return 0;
+}
+
/*
* Allocate some memory and give it an address in the guest physical address
* space.
@@ -663,12 +683,8 @@
/* Allocate page dirty bitmap if needed */
if ((new.flags & KVM_MEM_LOG_DIRTY_PAGES) && !new.dirty_bitmap) {
- unsigned long dirty_bytes = kvm_dirty_bitmap_bytes(&new);
-
- new.dirty_bitmap = vmalloc(dirty_bytes);
- if (!new.dirty_bitmap)
+ if (kvm_create_dirty_bitmap(&new) < 0)
goto out_free;
- memset(new.dirty_bitmap, 0, dirty_bytes);
/* destroy any largepage mappings for dirty tracking */
if (old.npages)
flush_shadow = 1;