KVM: Use alignment properties of vcpu to simplify FPU ops
Now we use a kmem cache for allocating vcpus, we can get the 16-byte
alignment required by fxsave & fxrstor instructions, and avoid
manually aligning the buffer.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Avi Kivity <avi@qumranet.com>
diff --git a/drivers/kvm/kvm.h b/drivers/kvm/kvm.h
index b362e8f..7a34706 100644
--- a/drivers/kvm/kvm.h
+++ b/drivers/kvm/kvm.h
@@ -45,10 +45,6 @@
#define KVM_REFILL_PAGES 25
#define KVM_MAX_CPUID_ENTRIES 40
-#define FX_IMAGE_SIZE 512
-#define FX_IMAGE_ALIGN 16
-#define FX_BUF_SIZE (2 * FX_IMAGE_SIZE + FX_IMAGE_ALIGN)
-
#define DE_VECTOR 0
#define NM_VECTOR 7
#define DF_VECTOR 8
@@ -342,9 +338,8 @@
struct kvm_guest_debug guest_debug;
- char fx_buf[FX_BUF_SIZE];
- char *host_fx_image;
- char *guest_fx_image;
+ struct i387_fxsave_struct host_fx_image;
+ struct i387_fxsave_struct guest_fx_image;
int fpu_active;
int guest_fpu_loaded;
@@ -704,12 +699,12 @@
}
#endif
-static inline void fx_save(void *image)
+static inline void fx_save(struct i387_fxsave_struct *image)
{
asm ("fxsave (%0)":: "r" (image));
}
-static inline void fx_restore(void *image)
+static inline void fx_restore(struct i387_fxsave_struct *image)
{
asm ("fxrstor (%0)":: "r" (image));
}