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 <endian.h>
  19 #include <byteswap.h>
  20
  21 #include "ubd.h"
  22 #include <os.h>
  23
  24 int start_io_thread(unsigned long sp, int *fd_out)
  25 {
  26         int pid, fds[2], err;
  27
  28         err = os_pipe(fds, 1, 1);
  29         if(err < 0){
  30                 printk("start_io_thread - os_pipe failed, err = %d\n", -err);
  31                 goto out;
  32         }
  33
  34         kernel_fd = fds[0];
  35         *fd_out = fds[1];
  36
  37         err = os_set_fd_block(*fd_out, 0);
  38         if (err) {
  39                 printk("start_io_thread - failed to set nonblocking I/O.\n");
  40                 goto out_close;
  41         }
  42
  43         pid = clone(io_thread, (void *) sp, CLONE_FILES | CLONE_VM, NULL);
  44         if(pid < 0){
  45                 err = -errno;
  46                 printk("start_io_thread - clone failed : errno = %d\n", errno);
  47                 goto out_close;
  48         }
  49
  50         return(pid);
  51
  52  out_close:
  53         os_close_file(fds[0]);
  54         os_close_file(fds[1]);
  55         kernel_fd = -1;
  56         *fd_out = -1;
  57  out:
  58         return err;
  59 }