arch/um/drivers/ubd_user.c

   1 /*
   2  * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
   3  * Copyright (C) 2001 Ridgerun,Inc (glonnon@ridgerun.com)
   4  * Licensed under the GPL
   5  */
   6
   7 #include <stddef.h>
   8 #include <unistd.h>
   9 #include <errno.h>
  10 #include <sched.h>
  11 #include <signal.h>
  12 #include <string.h>
  13 #include <netinet/in.h>
  14 #include <sys/time.h>
  15 #include <sys/socket.h>
  16 #include <sys/mman.h>
  17 #include <sys/param.h>
  18 #include "asm/types.h"
  19 #include "user.h"
  20 #include "ubd_user.h"
  21 #include "os.h"
  22 #include "cow.h"
  23
  24 #include <endian.h>
  25 #include <byteswap.h>
  26
  27 void ignore_sigwinch_sig(void)
  28 {
  29         signal(SIGWINCH, SIG_IGN);
  30 }
  31
  32 int start_io_thread(unsigned long sp, int *fd_out)
  33 {
  34         int pid, fds[2], err;
  35
  36         err = os_pipe(fds, 1, 1);
  37         if(err < 0){
  38                 printk("start_io_thread - os_pipe failed, err = %d\n", -err);
  39                 goto out;
  40         }
  41
  42         kernel_fd = fds[0];
  43         *fd_out = fds[1];
  44
  45         err = os_set_fd_block(*fd_out, 0);
  46         if (err) {
  47                 printk("start_io_thread - failed to set nonblocking I/O.\n");
  48                 goto out_close;
  49         }
  50
  51         pid = clone(io_thread, (void *) sp, CLONE_FILES | CLONE_VM, NULL);
  52         if(pid < 0){
  53                 err = -errno;
  54                 printk("start_io_thread - clone failed : errno = %d\n", errno);
  55                 goto out_close;
  56         }
  57
  58         return(pid);
  59
  60  out_close:
  61         os_close_file(fds[0]);
  62         os_close_file(fds[1]);
  63         kernel_fd = -1;
  64         *fd_out = -1;
  65  out:
  66         return err;
  67 }