x86: Introduce 'struct fpu' and related API

Currently all fpu state access is through tsk->thread.xstate.  Since we wish
to generalize fpu access to non-task contexts, wrap the state in a new
'struct fpu' and convert existing access to use an fpu API.

Signal frame handlers are not converted to the API since they will remain
task context only things.

Signed-off-by: Avi Kivity <avi@redhat.com>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <1273135546-29690-3-git-send-email-avi@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

1 files changed, 5 insertions, 1 deletions

diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index b753ea59703a..b684f587647c 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -380,6 +380,10 @@ union thread_xstate {
         struct xsave_struct             xsave;
 };
 
+struct fpu {
+        union thread_xstate *state;
+};
+
 #ifdef CONFIG_X86_64
 DECLARE_PER_CPU(struct orig_ist, orig_ist);
 
@@ -457,7 +461,7 @@ struct thread_struct {
         unsigned long           trap_no;
         unsigned long           error_code;
         /* floating point and extended processor state */
-        union thread_xstate     *xstate;
+        struct fpu              fpu;
 #ifdef CONFIG_X86_32
         /* Virtual 86 mode info */
         struct vm86_struct __user *vm86_info;