xref: /linux/arch/um/drivers/ubd_user.c (revision cc04a46f11ea046ed53e2c832ae29e4790f7e35f)
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 }
60