arch/um/kernel/exec.c

   1 /*
   2  * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
   3  * Licensed under the GPL
   4  */
   5
   6 #include <linux/stddef.h>
   7 #include <linux/module.h>
   8 #include <linux/fs.h>
   9 #include <linux/ptrace.h>
  10 #include <linux/sched.h>
  11 #include <linux/slab.h>
  12 #include <asm/current.h>
  13 #include <asm/processor.h>
  14 #include <asm/uaccess.h>
  15 #include "as-layout.h"
  16 #include "mem_user.h"
  17 #include "skas.h"
  18 #include "os.h"
  19 #include "internal.h"
  20
  21 void flush_thread(void)
  22 {
  23         void *data = NULL;
  24         int ret;
  25
  26         arch_flush_thread(&current->thread.arch);
  27
  28         ret = unmap(&current->mm->context.id, 0, STUB_START, 0, &data);
  29         ret = ret || unmap(&current->mm->context.id, STUB_END,
  30                            host_task_size - STUB_END, 1, &data);
  31         if (ret) {
  32                 printk(KERN_ERR "flush_thread - clearing address space failed, "
  33                        "err = %d\n", ret);
  34                 force_sig(SIGKILL, current);
  35         }
  36
  37         __switch_mm(&current->mm->context.id);
  38 }
  39
  40 void start_thread(struct pt_regs *regs, unsigned long eip, unsigned long esp)
  41 {
  42         get_safe_registers(regs->regs.gp, regs->regs.fp);
  43         PT_REGS_IP(regs) = eip;
  44         PT_REGS_SP(regs) = esp;
  45         current->ptrace &= ~PT_DTRACE;
  46 #ifdef SUBARCH_EXECVE1
  47         SUBARCH_EXECVE1(regs->regs);
  48 #endif
  49 }
  50 EXPORT_SYMBOL(start_thread);
  51
  52 long um_execve(const char *file, const char __user *const __user *argv, const char __user *const __user *env)
  53 {
  54         long err;
  55
  56         err = do_execve(file, argv, env, &current->thread.regs);
  57         if (!err)
  58                 UML_LONGJMP(current->thread.exec_buf, 1);
  59         return err;
  60 }
  61
  62 long sys_execve(const char __user *file, const char __user *const __user *argv,
  63                 const char __user *const __user *env)
  64 {
  65         long error;
  66         char *filename;
  67
  68         filename = getname(file);
  69         error = PTR_ERR(filename);
  70         if (IS_ERR(filename)) goto out;
  71         error = do_execve(filename, argv, env, &current->thread.regs);
  72         putname(filename);
  73  out:
  74         return error;
  75 }