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Diffstat (limited to 'arch/x86/include/asm/xsave.h')
| -rw-r--r-- | arch/x86/include/asm/xsave.h | 151 |
1 files changed, 151 insertions, 0 deletions
diff --git a/arch/x86/include/asm/xsave.h b/arch/x86/include/asm/xsave.h new file mode 100644 index 00000000000..d949ef28c48 --- /dev/null +++ b/arch/x86/include/asm/xsave.h @@ -0,0 +1,151 @@ +#ifndef __ASM_X86_XSAVE_H +#define __ASM_X86_XSAVE_H + +#include <linux/types.h> +#include <asm/processor.h> + +#define XSTATE_CPUID 0x0000000d + +#define XSTATE_FP 0x1 +#define XSTATE_SSE 0x2 +#define XSTATE_YMM 0x4 +#define XSTATE_BNDREGS 0x8 +#define XSTATE_BNDCSR 0x10 +#define XSTATE_OPMASK 0x20 +#define XSTATE_ZMM_Hi256 0x40 +#define XSTATE_Hi16_ZMM 0x80 + +#define XSTATE_FPSSE (XSTATE_FP | XSTATE_SSE) +/* Bit 63 of XCR0 is reserved for future expansion */ +#define XSTATE_EXTEND_MASK (~(XSTATE_FPSSE | (1ULL << 63))) + +#define FXSAVE_SIZE 512 + +#define XSAVE_HDR_SIZE 64 +#define XSAVE_HDR_OFFSET FXSAVE_SIZE + +#define XSAVE_YMM_SIZE 256 +#define XSAVE_YMM_OFFSET (XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET) + +/* Supported features which support lazy state saving */ +#define XSTATE_LAZY (XSTATE_FP | XSTATE_SSE | XSTATE_YMM \ + | XSTATE_OPMASK | XSTATE_ZMM_Hi256 | XSTATE_Hi16_ZMM) + +/* Supported features which require eager state saving */ +#define XSTATE_EAGER (XSTATE_BNDREGS | XSTATE_BNDCSR) + +/* All currently supported features */ +#define XCNTXT_MASK (XSTATE_LAZY | XSTATE_EAGER) + +#ifdef CONFIG_X86_64 +#define REX_PREFIX "0x48, " +#else +#define REX_PREFIX +#endif + +extern unsigned int xstate_size; +extern u64 pcntxt_mask; +extern u64 xstate_fx_sw_bytes[USER_XSTATE_FX_SW_WORDS]; +extern struct xsave_struct *init_xstate_buf; + +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) +{ + 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; + + /* + * Clear the xsave header first, so that reserved fields are + * initialized to zero. + */ + err = __clear_user(&buf->xsave_hdr, sizeof(buf->xsave_hdr)); + if (unlikely(err)) + return -EFAULT; + + __asm__ __volatile__(ASM_STAC "\n" + "1: .byte " REX_PREFIX "0x0f,0xae,0x27\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) + : "D" (buf), "a" (-1), "d" (-1), "0" (0) + : "memory"); + 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__(ASM_STAC "\n" + "1: .byte " REX_PREFIX "0x0f,0xae,0x2f\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) + : "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; + + 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 |