diff options
Diffstat (limited to 'arch/x86/include')
-rw-r--r-- | arch/x86/include/asm/alternative.h | 14 | ||||
-rw-r--r-- | arch/x86/include/asm/fpu-internal.h | 9 | ||||
-rw-r--r-- | arch/x86/include/asm/processor.h | 4 | ||||
-rw-r--r-- | arch/x86/include/asm/xsave.h | 223 |
4 files changed, 189 insertions, 61 deletions
diff --git a/arch/x86/include/asm/alternative.h b/arch/x86/include/asm/alternative.h index 0a3f9c9..473bdbe 100644 --- a/arch/x86/include/asm/alternative.h +++ b/arch/x86/include/asm/alternative.h @@ -161,6 +161,20 @@ static inline int alternatives_text_reserved(void *start, void *end) asm volatile (ALTERNATIVE(oldinstr, newinstr, feature) \ : : "i" (0), ## input) +/* + * This is similar to alternative_input. But it has two features and + * respective instructions. + * + * If CPU has feature2, newinstr2 is used. + * Otherwise, if CPU has feature1, newinstr1 is used. + * Otherwise, oldinstr is used. + */ +#define alternative_input_2(oldinstr, newinstr1, feature1, newinstr2, \ + feature2, input...) \ + asm volatile(ALTERNATIVE_2(oldinstr, newinstr1, feature1, \ + newinstr2, feature2) \ + : : "i" (0), ## input) + /* Like alternative_input, but with a single output argument */ #define alternative_io(oldinstr, newinstr, feature, output, input...) \ asm volatile (ALTERNATIVE(oldinstr, newinstr, feature) \ diff --git a/arch/x86/include/asm/fpu-internal.h b/arch/x86/include/asm/fpu-internal.h index e3b8542..412ecec 100644 --- a/arch/x86/include/asm/fpu-internal.h +++ b/arch/x86/include/asm/fpu-internal.h @@ -508,9 +508,12 @@ static inline void user_fpu_begin(void) static inline void __save_fpu(struct task_struct *tsk) { - if (use_xsave()) - xsave_state(&tsk->thread.fpu.state->xsave, -1); - else + if (use_xsave()) { + if (unlikely(system_state == SYSTEM_BOOTING)) + xsave_state_booting(&tsk->thread.fpu.state->xsave, -1); + else + xsave_state(&tsk->thread.fpu.state->xsave, -1); + } else fpu_fxsave(&tsk->thread.fpu); } diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index ee30b9f..eb71ec7 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -385,8 +385,8 @@ struct bndcsr_struct { struct xsave_hdr_struct { u64 xstate_bv; - u64 reserved1[2]; - u64 reserved2[5]; + u64 xcomp_bv; + u64 reserved[6]; } __attribute__((packed)); struct xsave_struct { diff --git a/arch/x86/include/asm/xsave.h b/arch/x86/include/asm/xsave.h index d949ef2..7e7a79a 100644 --- a/arch/x86/include/asm/xsave.h +++ b/arch/x86/include/asm/xsave.h @@ -52,24 +52,170 @@ extern void xsave_init(void); extern void update_regset_xstate_info(unsigned int size, u64 xstate_mask); extern int init_fpu(struct task_struct *child); -static inline int fpu_xrstor_checking(struct xsave_struct *fx) +/* These macros all use (%edi)/(%rdi) as the single memory argument. */ +#define XSAVE ".byte " REX_PREFIX "0x0f,0xae,0x27" +#define XSAVEOPT ".byte " REX_PREFIX "0x0f,0xae,0x37" +#define XSAVES ".byte " REX_PREFIX "0x0f,0xc7,0x2f" +#define XRSTOR ".byte " REX_PREFIX "0x0f,0xae,0x2f" +#define XRSTORS ".byte " REX_PREFIX "0x0f,0xc7,0x1f" + +#define xstate_fault ".section .fixup,\"ax\"\n" \ + "3: movl $-1,%[err]\n" \ + " jmp 2b\n" \ + ".previous\n" \ + _ASM_EXTABLE(1b, 3b) \ + : [err] "=r" (err) + +/* + * This function is called only during boot time when x86 caps are not set + * up and alternative can not be used yet. + */ +static inline int xsave_state_booting(struct xsave_struct *fx, u64 mask) { - int err; + u32 lmask = mask; + u32 hmask = mask >> 32; + int err = 0; + + WARN_ON(system_state != SYSTEM_BOOTING); + + if (boot_cpu_has(X86_FEATURE_XSAVES)) + asm volatile("1:"XSAVES"\n\t" + "2:\n\t" + : : "D" (fx), "m" (*fx), "a" (lmask), "d" (hmask) + : "memory"); + else + asm volatile("1:"XSAVE"\n\t" + "2:\n\t" + : : "D" (fx), "m" (*fx), "a" (lmask), "d" (hmask) + : "memory"); + + asm volatile(xstate_fault + : "0" (0) + : "memory"); + + return err; +} + +/* + * This function is called only during boot time when x86 caps are not set + * up and alternative can not be used yet. + */ +static inline int xrstor_state_booting(struct xsave_struct *fx, u64 mask) +{ + u32 lmask = mask; + u32 hmask = mask >> 32; + int err = 0; + + WARN_ON(system_state != SYSTEM_BOOTING); - 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) + if (boot_cpu_has(X86_FEATURE_XSAVES)) + asm volatile("1:"XRSTORS"\n\t" + "2:\n\t" + : : "D" (fx), "m" (*fx), "a" (lmask), "d" (hmask) + : "memory"); + else + asm volatile("1:"XRSTOR"\n\t" + "2:\n\t" + : : "D" (fx), "m" (*fx), "a" (lmask), "d" (hmask) + : "memory"); + + asm volatile(xstate_fault + : "0" (0) + : "memory"); + + return err; +} + +/* + * Save processor xstate to xsave area. + */ +static inline int 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"); return err; } +/* + * 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; +} + +/* + * Save xstate context for old process during context switch. + */ +static inline void fpu_xsave(struct fpu *fpu) +{ + xsave_state(&fpu->state->xsave, -1); +} + +/* + * Restore xstate context for new process during context switch. + */ +static inline int fpu_xrstor_checking(struct xsave_struct *fx) +{ + return xrstor_state(fx, -1); +} + +/* + * Save xstate to user space xsave area. + * + * We don't use modified optimization because xrstor/xrstors might track + * a different application. + * + * We don't use compacted format xsave area for + * backward compatibility for old applications which don't understand + * compacted format of xsave area. + */ static inline int xsave_user(struct xsave_struct __user *buf) { int err; @@ -83,69 +229,34 @@ static inline int xsave_user(struct xsave_struct __user *buf) return -EFAULT; __asm__ __volatile__(ASM_STAC "\n" - "1: .byte " REX_PREFIX "0x0f,0xae,0x27\n" + "1:"XSAVE"\n" "2: " ASM_CLAC "\n" - ".section .fixup,\"ax\"\n" - "3: movl $-1,%[err]\n" - " jmp 2b\n" - ".previous\n" - _ASM_EXTABLE(1b,3b) - : [err] "=r" (err) + xstate_fault : "D" (buf), "a" (-1), "d" (-1), "0" (0) : "memory"); return err; } +/* + * Restore xstate from user space xsave area. + */ static inline int xrestore_user(struct xsave_struct __user *buf, u64 mask) { - int err; + int err = 0; struct xsave_struct *xstate = ((__force struct xsave_struct *)buf); u32 lmask = mask; u32 hmask = mask >> 32; __asm__ __volatile__(ASM_STAC "\n" - "1: .byte " REX_PREFIX "0x0f,0xae,0x2f\n" + "1:"XRSTOR"\n" "2: " ASM_CLAC "\n" - ".section .fixup,\"ax\"\n" - "3: movl $-1,%[err]\n" - " jmp 2b\n" - ".previous\n" - _ASM_EXTABLE(1b,3b) - : [err] "=r" (err) + xstate_fault : "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_state(struct xsave_struct *fx, u64 mask) -{ - u32 lmask = mask; - u32 hmask = mask >> 32; +void *get_xsave_addr(struct xsave_struct *xsave, int xstate); +void setup_xstate_comp(void); - 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 - an addressing mode that doesn't require extended registers. */ - alternative_input( - ".byte " REX_PREFIX "0x0f,0xae,0x27", - ".byte " REX_PREFIX "0x0f,0xae,0x37", - X86_FEATURE_XSAVEOPT, - [fx] "D" (&fpu->state->xsave), "a" (-1), "d" (-1) : - "memory"); -} #endif |