#ifndef _UAPI_ASM_X86_SIGCONTEXT_H #define _UAPI_ASM_X86_SIGCONTEXT_H /* * Linux signal context definitions. The sigcontext includes a complex hierarchy of CPU * and FPU state, available to user-space (on the stack) when a signal handler is * executed. * * As over the years this ABI grew from its very simple roots towards supporting more and * more CPU state organically, some of the details (which were rather clever hacks back * in the days) became a bit quirky by today. * * The current ABI includes flexible provisions for future extensions, so we won't have * to grow new quirks for quite some time. Promise! */ #include #include #define FP_XSTATE_MAGIC1 0x46505853U #define FP_XSTATE_MAGIC2 0x46505845U #define FP_XSTATE_MAGIC2_SIZE sizeof(FP_XSTATE_MAGIC2) /* * Bytes 464..511 in the current 512-byte layout of the FXSAVE/FXRSTOR frame * are reserved for SW usage. On CPUs supporting XSAVE/XRSTOR, these bytes * are used to extend the fpstate pointer in the sigcontext, which now * includes the extended state information along with fpstate information. * * If sw_reserved.magic1 == FP_XSTATE_MAGIC1 then there's a sw_reserved.extended_size * bytes large extended context area present. (The last 32-bit word of this extended * area (at the fpstate+extended_size-FP_XSTATE_MAGIC2_SIZE address) is set to * FP_XSTATE_MAGIC2 so that you can sanity check your size calculations.) * * This extended area typically grows with newer CPUs that have larger and larger * XSAVE areas. */ struct _fpx_sw_bytes { /* If set to FP_XSTATE_MAGIC1 then this is an xstate context. 0 if a legacy frame. */ __u32 magic1; /* * Total size of the fpstate area: * * - if magic1 == 0 then it's sizeof(struct _fpstate) * - if magic1 == FP_XSTATE_MAGIC1 then it's sizeof(struct _xstate) plus extensions (if any) */ __u32 extended_size; /* * Feature bit mask (including FP/SSE/extended state) that is present * in the memory layout: */ __u64 xfeatures; /* * Actual XSAVE state size, based on the xfeatures saved in the layout. * 'extended_size' is greater than 'xstate_size': */ __u32 xstate_size; /* For future use: */ __u32 padding[7]; }; #ifdef __i386__ /* * As documented in the iBCS2 standard: * * The first part of "struct _fpstate" is just the normal i387 * hardware setup, the extra "status" word is used to save the * coprocessor status word before entering the handler. * * The FPU state data structure has had to grow to accommodate the * extended FPU state required by the Streaming SIMD Extensions. * There is no documented standard to accomplish this at the moment. */ /* 10-byte legacy floating point register: */ struct _fpreg { unsigned short significand[4]; unsigned short exponent; }; /* 16-byte floating point register: */ struct _fpxreg { unsigned short significand[4]; unsigned short exponent; unsigned short padding[3]; }; /* 16-byte XMM register: */ struct _xmmreg { unsigned long element[4]; }; #define X86_FXSR_MAGIC 0x0000 struct _fpstate { /* Legacy FPU environment: */ unsigned long cw; unsigned long sw; unsigned long tag; unsigned long ipoff; unsigned long cssel; unsigned long dataoff; unsigned long datasel; struct _fpreg _st[8]; unsigned short status; unsigned short magic; /* 0xffff: regular FPU data only */ /* 0x0000: FXSR FPU data */ /* FXSR FPU environment */ unsigned long _fxsr_env[6]; /* FXSR FPU env is ignored */ unsigned long mxcsr; unsigned long reserved; struct _fpxreg _fxsr_st[8]; /* FXSR FPU reg data is ignored */ struct _xmmreg _xmm[8]; /* First 8 XMM registers */ unsigned long padding1[44]; /* Second 8 XMM registers plus padding */ union { unsigned long padding2[12]; struct _fpx_sw_bytes sw_reserved; /* Potential extended state is encoded here */ }; }; #else /* __x86_64__: */ /* * The FXSAVE frame. * * Note1: If sw_reserved.magic1 == FP_XSTATE_MAGIC1 then the structure is * larger: 'struct _xstate'. Note that 'struct _xstate' embedds * 'struct _fpstate' so that you can always assume the _fpstate portion * exists so that you can check the magic value. * * Note2: Reserved fields may someday contain valuable data. Always save/restore * them when you change signal frames. */ struct _fpstate { __u16 cwd; __u16 swd; /* Note this is not the same as the 32-bit/x87/FSAVE twd: */ __u16 twd; __u16 fop; __u64 rip; __u64 rdp; __u32 mxcsr; __u32 mxcsr_mask; __u32 st_space[32]; /* 8x FP registers, 16 bytes each */ __u32 xmm_space[64]; /* 16x XMM registers, 16 bytes each */ __u32 reserved2[12]; union { __u32 reserved3[12]; struct _fpx_sw_bytes sw_reserved; /* Potential extended state is encoded here */ }; }; #endif /* __x86_64__ */ struct _header { __u64 xfeatures; __u64 reserved1[2]; __u64 reserved2[5]; }; struct _ymmh_state { /* 16x YMM registers, 16 bytes each: */ __u32 ymmh_space[64]; }; /* * Extended state pointed to by sigcontext::fpstate. * * In addition to the fpstate, information encoded in _xstate::xstate_hdr * indicates the presence of other extended state information supported * by the CPU and kernel: */ struct _xstate { struct _fpstate fpstate; struct _header xstate_hdr; struct _ymmh_state ymmh; /* New processor state extensions go here: */ }; /* * The old user-space sigcontext definition, just in case user-space still * relies on it. The kernel definition (in asm/sigcontext.h) has unified * field names but otherwise the same layout. */ #ifndef __KERNEL__ # ifdef __i386__ struct sigcontext { unsigned short gs, __gsh; unsigned short fs, __fsh; unsigned short es, __esh; unsigned short ds, __dsh; unsigned long edi; unsigned long esi; unsigned long ebp; unsigned long esp; unsigned long ebx; unsigned long edx; unsigned long ecx; unsigned long eax; unsigned long trapno; unsigned long err; unsigned long eip; unsigned short cs, __csh; unsigned long eflags; unsigned long esp_at_signal; unsigned short ss, __ssh; struct _fpstate __user *fpstate; unsigned long oldmask; unsigned long cr2; }; # else /* __x86_64__: */ struct sigcontext { __u64 r8; __u64 r9; __u64 r10; __u64 r11; __u64 r12; __u64 r13; __u64 r14; __u64 r15; __u64 rdi; __u64 rsi; __u64 rbp; __u64 rbx; __u64 rdx; __u64 rax; __u64 rcx; __u64 rsp; __u64 rip; __u64 eflags; /* RFLAGS */ __u16 cs; __u16 gs; __u16 fs; __u16 __pad0; __u64 err; __u64 trapno; __u64 oldmask; __u64 cr2; struct _fpstate __user *fpstate; /* Zero when no FPU context */ # ifdef __ILP32__ __u32 __fpstate_pad; # endif __u64 reserved1[8]; }; # endif /* __x86_64__ */ #endif /* !__KERNEL__ */ #endif /* _UAPI_ASM_X86_SIGCONTEXT_H */