include/asm-x86_64/user.h

   1 #ifndef _X86_64_USER_H
   2 #define _X86_64_USER_H
   3
   4 #include <asm/types.h>
   5 #include <asm/page.h>
   6 /* Core file format: The core file is written in such a way that gdb
   7    can understand it and provide useful information to the user.
   8    There are quite a number of obstacles to being able to view the
   9    contents of the floating point registers, and until these are
  10    solved you will not be able to view the contents of them.
  11    Actually, you can read in the core file and look at the contents of
  12    the user struct to find out what the floating point registers
  13    contain.
  14
  15    The actual file contents are as follows:
  16    UPAGE: 1 page consisting of a user struct that tells gdb what is present
  17    in the file.  Directly after this is a copy of the task_struct, which
  18    is currently not used by gdb, but it may come in useful at some point.
  19    All of the registers are stored as part of the upage.  The upage should
  20    always be only one page.
  21    DATA: The data area is stored.  We use current->end_text to
  22    current->brk to pick up all of the user variables, plus any memory
  23    that may have been malloced.  No attempt is made to determine if a page
  24    is demand-zero or if a page is totally unused, we just cover the entire
  25    range.  All of the addresses are rounded in such a way that an integral
  26    number of pages is written.
  27    STACK: We need the stack information in order to get a meaningful
  28    backtrace.  We need to write the data from (esp) to
  29    current->start_stack, so we round each of these off in order to be able
  30    to write an integer number of pages.
  31    The minimum core file size is 3 pages, or 12288 bytes.  */
  32
  33 /*
  34  * Pentium III FXSR, SSE support
  35  *      Gareth Hughes <gareth@valinux.com>, May 2000
  36  *
  37  * Provide support for the GDB 5.0+ PTRACE_{GET|SET}FPXREGS requests for
  38  * interacting with the FXSR-format floating point environment.  Floating
  39  * point data can be accessed in the regular format in the usual manner,
  40  * and both the standard and SIMD floating point data can be accessed via
  41  * the new ptrace requests.  In either case, changes to the FPU environment
  42  * will be reflected in the task's state as expected.
  43  *
  44  * x86-64 support by Andi Kleen.
  45  */
  46
  47 /* This matches the 64bit FXSAVE format as defined by AMD. It is the same
  48    as the 32bit format defined by Intel, except that the selector:offset pairs for
  49    data and eip are replaced with flat 64bit pointers. */
  50 struct user_i387_struct {
  51         unsigned short  cwd;
  52         unsigned short  swd;
  53         unsigned short  twd; /* Note this is not the same as the 32bit/x87/FSAVE twd */
  54         unsigned short  fop;
  55         __u64   rip;
  56         __u64   rdp;
  57         __u32   mxcsr;
  58         __u32   mxcsr_mask;
  59         __u32   st_space[32];   /* 8*16 bytes for each FP-reg = 128 bytes */
  60         __u32   xmm_space[64];  /* 16*16 bytes for each XMM-reg = 256 bytes */
  61         __u32   padding[24];
  62 };
  63
  64 /*
  65  * Segment register layout in coredumps.
  66  */
  67 struct user_regs_struct {
  68         unsigned long r15,r14,r13,r12,rbp,rbx,r11,r10;
  69         unsigned long r9,r8,rax,rcx,rdx,rsi,rdi,orig_rax;
  70         unsigned long rip,cs,eflags;
  71         unsigned long rsp,ss;
  72         unsigned long fs_base, gs_base;
  73         unsigned long ds,es,fs,gs;
  74 };
  75
  76 /* When the kernel dumps core, it starts by dumping the user struct -
  77    this will be used by gdb to figure out where the data and stack segments
  78    are within the file, and what virtual addresses to use. */
  79 struct user{
  80 /* We start with the registers, to mimic the way that "memory" is returned
  81    from the ptrace(3,...) function.  */
  82   struct user_regs_struct regs;         /* Where the registers are actually stored */
  83 /* ptrace does not yet supply these.  Someday.... */
  84   int u_fpvalid;                /* True if math co-processor being used. */
  85                                 /* for this mess. Not yet used. */
  86   int pad0;
  87   struct user_i387_struct i387; /* Math Co-processor registers. */
  88 /* The rest of this junk is to help gdb figure out what goes where */
  89   unsigned long int u_tsize;    /* Text segment size (pages). */
  90   unsigned long int u_dsize;    /* Data segment size (pages). */
  91   unsigned long int u_ssize;    /* Stack segment size (pages). */
  92   unsigned long start_code;     /* Starting virtual address of text. */
  93   unsigned long start_stack;    /* Starting virtual address of stack area.
  94                                    This is actually the bottom of the stack,
  95                                    the top of the stack is always found in the
  96                                    esp register.  */
  97   long int signal;              /* Signal that caused the core dump. */
  98   int reserved;                 /* No longer used */
  99   int pad1;
 100   struct user_pt_regs * u_ar0;  /* Used by gdb to help find the values for */
 101                                 /* the registers. */
 102   struct user_i387_struct* u_fpstate;   /* Math Co-processor pointer. */
 103   unsigned long magic;          /* To uniquely identify a core file */
 104   char u_comm[32];              /* User command that was responsible */
 105   unsigned long u_debugreg[8];
 106   unsigned long error_code; /* CPU error code or 0 */
 107   unsigned long fault_address; /* CR3 or 0 */
 108 };
 109 #define NBPG PAGE_SIZE
 110 #define UPAGES 1
 111 #define HOST_TEXT_START_ADDR (u.start_code)
 112 #define HOST_STACK_END_ADDR (u.start_stack + u.u_ssize * NBPG)
 113
 114 #endif /* _X86_64_USER_H */