arch/um/kernel/tt/exec_kern.c

   1 /*
   2  * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
   3  * Licensed under the GPL
   4  */
   5
   6 #include "linux/kernel.h"
   7 #include "linux/mm.h"
   8 #include "asm/signal.h"
   9 #include "asm/ptrace.h"
  10 #include "asm/uaccess.h"
  11 #include "asm/pgalloc.h"
  12 #include "asm/tlbflush.h"
  13 #include "user_util.h"
  14 #include "kern_util.h"
  15 #include "irq_user.h"
  16 #include "mem_user.h"
  17 #include "os.h"
  18 #include "tlb.h"
  19 #include "mode.h"
  20
  21 static int exec_tramp(void *sig_stack)
  22 {
  23         init_new_thread_stack(sig_stack, NULL);
  24         init_new_thread_signals();
  25         os_stop_process(os_getpid());
  26         return(0);
  27 }
  28
  29 void flush_thread_tt(void)
  30 {
  31         unsigned long stack;
  32         int new_pid;
  33
  34         stack = alloc_stack(0, 0);
  35         if(stack == 0){
  36                 printk(KERN_ERR
  37                        "flush_thread : failed to allocate temporary stack\n");
  38                 do_exit(SIGKILL);
  39         }
  40
  41         new_pid = start_fork_tramp(task_stack_page(current), stack, 0, exec_tramp);
  42         if(new_pid < 0){
  43                 printk(KERN_ERR
  44                        "flush_thread : new thread failed, errno = %d\n",
  45                        -new_pid);
  46                 do_exit(SIGKILL);
  47         }
  48
  49         if(current_thread->cpu == 0)
  50                 forward_interrupts(new_pid);
  51         current->thread.request.op = OP_EXEC;
  52         current->thread.request.u.exec.pid = new_pid;
  53         unprotect_stack((unsigned long) current_thread);
  54         os_usr1_process(os_getpid());
  55         change_sig(SIGUSR1, 1);
  56
  57         change_sig(SIGUSR1, 0);
  58         enable_timer();
  59         free_page(stack);
  60         protect_memory(uml_reserved, high_physmem - uml_reserved, 1, 1, 0, 1);
  61         task_protections((unsigned long) current_thread);
  62         force_flush_all();
  63         unblock_signals();
  64 }
  65
  66 void start_thread_tt(struct pt_regs *regs, unsigned long eip,
  67                      unsigned long esp)
  68 {
  69         set_fs(USER_DS);
  70         flush_tlb_mm(current->mm);
  71         PT_REGS_IP(regs) = eip;
  72         PT_REGS_SP(regs) = esp;
  73         PT_FIX_EXEC_STACK(esp);
  74 }
  75
  76 /*
  77  * Overrides for Emacs so that we follow Linus's tabbing style.
  78  * Emacs will notice this stuff at the end of the file and automatically
  79  * adjust the settings for this buffer only.  This must remain at the end
  80  * of the file.
  81  * ---------------------------------------------------------------------------
  82  * Local variables:
  83  * c-file-style: "linux"
  84  * End:
  85  */