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#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 <linux/compiler.h>
#include <linux/types.h>
#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 */
};
};
# ifndef __KERNEL__
/*
* User-space might still rely on the old definition:
*/
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;
};
# endif /* !__KERNEL__ */
#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 */
};
};
# ifndef __KERNEL__
/*
* User-space might still rely on the old definition:
*/
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 /* !__KERNEL__ */
#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: */
};
#endif /* _UAPI_ASM_X86_SIGCONTEXT_H */
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