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