From: Fenghua Yu <[email protected]> If xsaves is eanbled, use xsaves/xrstors for saving and restoring xstate. xsaves supports compacted format, init optimization, modified optimization, and supervisor states.
Signed-off-by: Fenghua Yu <[email protected]> --- arch/x86/include/asm/xsave.h | 82 +++++++++++++++++++++++++++++++++----------- 1 file changed, 62 insertions(+), 20 deletions(-) diff --git a/arch/x86/include/asm/xsave.h b/arch/x86/include/asm/xsave.h index 76c2459..e538a0e 100644 --- a/arch/x86/include/asm/xsave.h +++ b/arch/x86/include/asm/xsave.h @@ -65,6 +65,68 @@ extern int init_fpu(struct task_struct *child); _ASM_EXTABLE(1b, 3b) \ : [err] "=r" (err) +/* + * Save processor xstate to xsave area. + */ +static inline void xsave_state(struct xsave_struct *fx, u64 mask) +{ + u32 lmask = mask; + u32 hmask = mask >> 32; + int err = 0; + + /* + * If xsaves is enabled, xsaves replaces xsaveopt because + * it supports compact format and supervisor states in addition to + * modified optimization in xsaveopt. + * + * Otherwise, if xsaveopt is enabled, xsaveopt replaces xsave + * because xsaveopt supports modified optimization which is not + * supported by xsave. + * + * If none of xsaves and xsaveopt is enabled, use xsave. + */ + alternative_input_2( + "1:"XSAVE, + "1:"XSAVEOPT, + X86_FEATURE_XSAVEOPT, + "1:"XSAVES, + X86_FEATURE_XSAVES, + [fx] "D" (fx), "a" (lmask), "d" (hmask) : + "memory"); + asm volatile("2:\n\t" + xstate_fault + : "0" (0) + : "memory"); +} + +/* + * Restore processor xstate from xsave area. + */ +static inline int xrstor_state(struct xsave_struct *fx, u64 mask) +{ + int err = 0; + u32 lmask = mask; + u32 hmask = mask >> 32; + + /* + * Use xrstors to restore context if it is enabled. xrstors supports + * compacted format of xsave area which is not supported by xrstor. + */ + alternative_input( + "1: " XRSTOR, + "1: " XRSTORS, + X86_FEATURE_XSAVES, + "D" (fx), "m" (*fx), "a" (lmask), "d" (hmask) + : "memory"); + + asm volatile("2:\n" + xstate_fault + : "0" (0) + : "memory"); + + return err; +} + static inline int fpu_xrstor_checking(struct xsave_struct *fx) { int err; @@ -130,26 +192,6 @@ static inline int xrestore_user(struct xsave_struct __user *buf, u64 mask) 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_state(struct xsave_struct *fx, u64 mask) -{ - u32 lmask = mask; - u32 hmask = mask >> 32; - - asm volatile(".byte " REX_PREFIX "0x0f,0xae,0x27\n\t" - : : "D" (fx), "m" (*fx), "a" (lmask), "d" (hmask) - : "memory"); -} - static inline void fpu_xsave(struct fpu *fpu) { /* This, however, we can work around by forcing the compiler to select -- 1.8.1.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
