arch/x86/include/asm/user_32.h

Source file repositories/reference/linux-study-clean/arch/x86/include/asm/user_32.h

File Facts

System
Linux kernel
Corpus path
arch/x86/include/asm/user_32.h
Extension
.h
Size
4895 bytes
Lines
129
Domain
Architecture Layer
Bucket
arch/x86
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

struct user_i387_struct {
	long	cwd;
	long	swd;
	long	twd;
	long	fip;
	long	fcs;
	long	foo;
	long	fos;
	long	st_space[20];	/* 8*10 bytes for each FP-reg = 80 bytes */
};

struct user_fxsr_struct {
	unsigned short	cwd;
	unsigned short	swd;
	unsigned short	twd;
	unsigned short	fop;
	long	fip;
	long	fcs;
	long	foo;
	long	fos;
	long	mxcsr;
	long	reserved;
	long	st_space[32];	/* 8*16 bytes for each FP-reg = 128 bytes */
	long	xmm_space[32];	/* 8*16 bytes for each XMM-reg = 128 bytes */
	long	padding[56];
};

/*
 * This is the old layout of "struct pt_regs", and
 * is still the layout used by user mode (the new
 * pt_regs doesn't have all registers as the kernel
 * doesn't use the extra segment registers)
 */
struct user_regs_struct {
	unsigned long	bx;
	unsigned long	cx;
	unsigned long	dx;
	unsigned long	si;
	unsigned long	di;
	unsigned long	bp;
	unsigned long	ax;
	unsigned long	ds;
	unsigned long	es;
	unsigned long	fs;
	unsigned long	gs;
	unsigned long	orig_ax;
	unsigned long	ip;
	unsigned long	cs;
	unsigned long	flags;
	unsigned long	sp;
	unsigned long	ss;
};

/* When the kernel dumps core, it starts by dumping the user struct -
   this will be used by gdb to figure out where the data and stack segments
   are within the file, and what virtual addresses to use. */
struct user{
/* We start with the registers, to mimic the way that "memory" is returned
   from the ptrace(3,...) function.  */
  struct user_regs_struct regs;	/* Where the registers are actually stored */
/* ptrace does not yet supply these.  Someday.... */
  int u_fpvalid;		/* True if math co-processor being used. */
				/* for this mess. Not yet used. */
  struct user_i387_struct i387;	/* Math Co-processor registers. */
/* The rest of this junk is to help gdb figure out what goes where */
  unsigned long int u_tsize;	/* Text segment size (pages). */
  unsigned long int u_dsize;	/* Data segment size (pages). */
  unsigned long int u_ssize;	/* Stack segment size (pages). */
  unsigned long start_code;     /* Starting virtual address of text. */
  unsigned long start_stack;	/* Starting virtual address of stack area.
				   This is actually the bottom of the stack,
				   the top of the stack is always found in the
				   esp register.  */
  long int signal;     		/* Signal that caused the core dump. */
  int reserved;			/* No longer used */
  unsigned long u_ar0;		/* Used by gdb to help find the values for */
				/* the registers. */
  struct user_i387_struct *u_fpstate;	/* Math Co-processor pointer. */
  unsigned long magic;		/* To uniquely identify a core file */
  char u_comm[32];		/* User command that was responsible */
  int u_debugreg[8];
};

#endif /* _ASM_X86_USER_32_H */

Annotation

Implementation Notes