arch/x86/um/os-Linux/registers.c

   1 /*
   2  * Copyright (C) 2004 PathScale, Inc
   3  * Copyright (C) 2004 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
   4  * Licensed under the GPL
   5  */
   6
   7 #include <errno.h>
   8 #include <stdlib.h>
   9 #include <sys/ptrace.h>
  10 #ifdef __i386__
  11 #include <sys/user.h>
  12 #endif
  13 #include <longjmp.h>
  14 #include <sysdep/ptrace_user.h>
  15 #include <sys/uio.h>
  16 #include <asm/sigcontext.h>
  17 #include <linux/elf.h>
  18 #include <registers.h>
  19 #include <sys/mman.h>
  20
  21 unsigned long host_fp_size;
  22
  23 int get_fp_registers(int pid, unsigned long *regs)
  24 {
  25         struct iovec iov = {
  26                 .iov_base = regs,
  27                 .iov_len = host_fp_size,
  28         };
  29
  30         if (ptrace(PTRACE_GETREGSET, pid, NT_X86_XSTATE, &iov) < 0)
  31                 return -errno;
  32         return 0;
  33 }
  34
  35 int put_fp_registers(int pid, unsigned long *regs)
  36 {
  37         struct iovec iov = {
  38                 .iov_base = regs,
  39                 .iov_len = host_fp_size,
  40         };
  41
  42         if (ptrace(PTRACE_SETREGSET, pid, NT_X86_XSTATE, &iov) < 0)
  43                 return -errno;
  44         return 0;
  45 }
  46
  47 int arch_init_registers(int pid)
  48 {
  49         struct iovec iov = {
  50                 /* Just use plenty of space, it does not cost us anything */
  51                 .iov_len = 2 * 1024 * 1024,
  52         };
  53         int ret;
  54
  55         iov.iov_base = mmap(NULL, iov.iov_len, PROT_WRITE | PROT_READ,
  56                             MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
  57         if (iov.iov_base == MAP_FAILED)
  58                 return -ENOMEM;
  59
  60         /* GDB has x86_xsave_length, which uses x86_cpuid_count */
  61         ret = ptrace(PTRACE_GETREGSET, pid, NT_X86_XSTATE, &iov);
  62         if (ret)
  63                 ret = -errno;
  64         munmap(iov.iov_base, 2 * 1024 * 1024);
  65
  66         host_fp_size = iov.iov_len;
  67
  68         return ret;
  69 }
  70
  71 unsigned long get_thread_reg(int reg, jmp_buf *buf)
  72 {
  73         switch (reg) {
  74 #ifdef __i386__
  75         case HOST_IP:
  76                 return buf[0]->__eip;
  77         case HOST_SP:
  78                 return buf[0]->__esp;
  79         case HOST_BP:
  80                 return buf[0]->__ebp;
  81 #else
  82         case HOST_IP:
  83                 return buf[0]->__rip;
  84         case HOST_SP:
  85                 return buf[0]->__rsp;
  86         case HOST_BP:
  87                 return buf[0]->__rbp;
  88 #endif
  89         default:
  90                 printk(UM_KERN_ERR "get_thread_regs - unknown register %d\n",
  91                        reg);
  92                 return 0;
  93         }
  94 }