arch/um/os-Linux/sys-i386/registers.c

   1 /*
   2  * Copyright (C) 2004 PathScale, Inc
   3  * Licensed under the GPL
   4  */
   5
   6 #include <errno.h>
   7 #include <string.h>
   8 #include "sysdep/ptrace_user.h"
   9 #include "sysdep/ptrace.h"
  10 #include "uml-config.h"
  11 #include "skas_ptregs.h"
  12 #include "registers.h"
  13 #include "user.h"
  14
  15 /* These are set once at boot time and not changed thereafter */
  16
  17 static unsigned long exec_regs[HOST_FRAME_SIZE];
  18 static unsigned long exec_fp_regs[HOST_FP_SIZE];
  19 static unsigned long exec_fpx_regs[HOST_XFP_SIZE];
  20 static int have_fpx_regs = 1;
  21
  22 void init_thread_registers(union uml_pt_regs *to)
  23 {
  24         memcpy(to->skas.regs, exec_regs, sizeof(to->skas.regs));
  25         memcpy(to->skas.fp, exec_fp_regs, sizeof(to->skas.fp));
  26         if(have_fpx_regs)
  27                 memcpy(to->skas.xfp, exec_fpx_regs, sizeof(to->skas.xfp));
  28 }
  29
  30 /* XXX These need to use [GS]ETFPXREGS and copy_sc_{to,from}_user_skas needs
  31  * to pass in a sufficiently large buffer
  32  */
  33 int save_fp_registers(int pid, unsigned long *fp_regs)
  34 {
  35         if(ptrace(PTRACE_GETFPREGS, pid, 0, fp_regs) < 0)
  36                 return(-errno);
  37         return(0);
  38 }
  39
  40 int restore_fp_registers(int pid, unsigned long *fp_regs)
  41 {
  42         if(ptrace(PTRACE_SETFPREGS, pid, 0, fp_regs) < 0)
  43                 return(-errno);
  44         return(0);
  45 }
  46
  47 static int move_registers(int pid, int int_op, union uml_pt_regs *regs,
  48                           int fp_op, unsigned long *fp_regs)
  49 {
  50         if(ptrace(int_op, pid, 0, regs->skas.regs) < 0)
  51                 return(-errno);
  52
  53         if(ptrace(fp_op, pid, 0, fp_regs) < 0)
  54                 return(-errno);
  55
  56         return(0);
  57 }
  58
  59 void save_registers(int pid, union uml_pt_regs *regs)
  60 {
  61         unsigned long *fp_regs;
  62         int err, fp_op;
  63
  64         if(have_fpx_regs){
  65                 fp_op = PTRACE_GETFPXREGS;
  66                 fp_regs = regs->skas.xfp;
  67         }
  68         else {
  69                 fp_op = PTRACE_GETFPREGS;
  70                 fp_regs = regs->skas.fp;
  71         }
  72
  73         err = move_registers(pid, PTRACE_GETREGS, regs, fp_op, fp_regs);
  74         if(err)
  75                 panic("save_registers - saving registers failed, errno = %d\n",
  76                       -err);
  77 }
  78
  79 void restore_registers(int pid, union uml_pt_regs *regs)
  80 {
  81         unsigned long *fp_regs;
  82         int err, fp_op;
  83
  84         if(have_fpx_regs){
  85                 fp_op = PTRACE_SETFPXREGS;
  86                 fp_regs = regs->skas.xfp;
  87         }
  88         else {
  89                 fp_op = PTRACE_SETFPREGS;
  90                 fp_regs = regs->skas.fp;
  91         }
  92
  93         err = move_registers(pid, PTRACE_SETREGS, regs, fp_op, fp_regs);
  94         if(err)
  95                 panic("restore_registers - saving registers failed, "
  96                       "errno = %d\n", -err);
  97 }
  98
  99 void init_registers(int pid)
 100 {
 101         int err;
 102
 103         err = ptrace(PTRACE_GETREGS, pid, 0, exec_regs);
 104         if(err)
 105                 panic("check_ptrace : PTRACE_GETREGS failed, errno = %d",
 106                       err);
 107
 108         err = ptrace(PTRACE_GETFPXREGS, pid, 0, exec_fpx_regs);
 109         if(!err)
 110                 return;
 111
 112         have_fpx_regs = 0;
 113         if(err != EIO)
 114                 panic("check_ptrace : PTRACE_GETFPXREGS failed, errno = %d",
 115                       err);
 116
 117         err = ptrace(PTRACE_GETFPREGS, pid, 0, exec_fp_regs);
 118         if(err)
 119                 panic("check_ptrace : PTRACE_GETFPREGS failed, errno = %d",
 120                       err);
 121 }
 122
 123 /*
 124  * Overrides for Emacs so that we follow Linus's tabbing style.
 125  * Emacs will notice this stuff at the end of the file and automatically
 126  * adjust the settings for this buffer only.  This must remain at the end
 127  * of the file.
 128  * ---------------------------------------------------------------------------
 129  * Local variables:
 130  * c-file-style: "linux"
 131  * End:
 132  */