diff options
Diffstat (limited to 'arch/x86/include/asm/xsave.h')
-rw-r--r-- | arch/x86/include/asm/xsave.h | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/arch/x86/include/asm/xsave.h b/arch/x86/include/asm/xsave.h new file mode 100644 index 0000000..08e9a1a --- /dev/null +++ b/arch/x86/include/asm/xsave.h @@ -0,0 +1,118 @@ +#ifndef __ASM_X86_XSAVE_H +#define __ASM_X86_XSAVE_H + +#include <linux/types.h> +#include <asm/processor.h> +#include <asm/i387.h> + +#define XSTATE_FP 0x1 +#define XSTATE_SSE 0x2 + +#define XSTATE_FPSSE (XSTATE_FP | XSTATE_SSE) + +#define FXSAVE_SIZE 512 + +/* + * These are the features that the OS can handle currently. + */ +#define XCNTXT_MASK (XSTATE_FP | XSTATE_SSE) + +#ifdef CONFIG_X86_64 +#define REX_PREFIX "0x48, " +#else +#define REX_PREFIX +#endif + +extern unsigned int xstate_size; +extern u64 pcntxt_mask; +extern struct xsave_struct *init_xstate_buf; + +extern void xsave_cntxt_init(void); +extern void xsave_init(void); +extern int init_fpu(struct task_struct *child); +extern int check_for_xstate(struct i387_fxsave_struct __user *buf, + void __user *fpstate, + struct _fpx_sw_bytes *sw); + +static inline int xrstor_checking(struct xsave_struct *fx) +{ + int err; + + asm volatile("1: .byte " REX_PREFIX "0x0f,0xae,0x2f\n\t" + "2:\n" + ".section .fixup,\"ax\"\n" + "3: movl $-1,%[err]\n" + " jmp 2b\n" + ".previous\n" + _ASM_EXTABLE(1b, 3b) + : [err] "=r" (err) + : "D" (fx), "m" (*fx), "a" (-1), "d" (-1), "0" (0) + : "memory"); + + return err; +} + +static inline int xsave_user(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, u64 mask) +{ + int err; + struct xsave_struct *xstate = ((__force struct xsave_struct *)buf); + u32 lmask = mask; + u32 hmask = mask >> 32; + + __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, u64 mask) +{ + u32 lmask = mask; + u32 hmask = mask >> 32; + + 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) +{ + /* This, however, we can work around by forcing the compiler to select + an addressing mode that doesn't require extended registers. */ + __asm__ __volatile__(".byte " REX_PREFIX "0x0f,0xae,0x27" + : : "D" (&(tsk->thread.xstate->xsave)), + "a" (-1), "d"(-1) : "memory"); +} +#endif |