x86, xsave: xsave/xrstor specific routines

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Suresh Siddha 2008-07-29 10:29:23 -07:00 committed by Ingo Molnar
parent ab5137015f
commit 9dc89c0f96
1 changed files with 52 additions and 0 deletions

View File

@ -48,6 +48,58 @@ static inline int xrstor_checking(struct xsave_struct *fx)
return err; return err;
} }
static inline int xsave_check(struct xsave_struct __user *buf)
{
int err;
__asm__ __volatile__("1: .byte " REX_PREFIX "0x0f,0xae,0x27\n"
"2:\n"
".section .fixup,\"ax\"\n"
"3: movl $-1,%[err]\n"
" jmp 2b\n"
".previous\n"
".section __ex_table,\"a\"\n"
_ASM_ALIGN "\n"
_ASM_PTR "1b,3b\n"
".previous"
: [err] "=r" (err)
: "D" (buf), "a" (-1), "d" (-1), "0" (0)
: "memory");
if (unlikely(err) && __clear_user(buf, xstate_size))
err = -EFAULT;
/* No need to clear here because the caller clears USED_MATH */
return err;
}
static inline int xrestore_user(struct xsave_struct __user *buf,
unsigned int lmask,
unsigned int hmask)
{
int err;
struct xsave_struct *xstate = ((__force struct xsave_struct *)buf);
__asm__ __volatile__("1: .byte " REX_PREFIX "0x0f,0xae,0x2f\n"
"2:\n"
".section .fixup,\"ax\"\n"
"3: movl $-1,%[err]\n"
" jmp 2b\n"
".previous\n"
".section __ex_table,\"a\"\n"
_ASM_ALIGN "\n"
_ASM_PTR "1b,3b\n"
".previous"
: [err] "=r" (err)
: "D" (xstate), "a" (lmask), "d" (hmask), "0" (0)
: "memory"); /* memory required? */
return err;
}
static inline void xrstor_state(struct xsave_struct *fx, int lmask, int hmask)
{
asm volatile(".byte " REX_PREFIX "0x0f,0xae,0x2f\n\t"
: : "D" (fx), "m" (*fx), "a" (lmask), "d" (hmask)
: "memory");
}
static inline void xsave(struct task_struct *tsk) static inline void xsave(struct task_struct *tsk)
{ {
/* This, however, we can work around by forcing the compiler to select /* This, however, we can work around by forcing the compiler to select