xref: /linux/arch/um/drivers/ubd_user.c (revision 4413e16d9d21673bb5048a2e542f1aaa00015c2e)
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 void ignore_sigwinch_sig(void)
25 {
26 	signal(SIGWINCH, SIG_IGN);
27 }
28 
29 int start_io_thread(unsigned long sp, int *fd_out)
30 {
31 	int pid, fds[2], err;
32 
33 	err = os_pipe(fds, 1, 1);
34 	if(err < 0){
35 		printk("start_io_thread - os_pipe failed, err = %d\n", -err);
36 		goto out;
37 	}
38 
39 	kernel_fd = fds[0];
40 	*fd_out = fds[1];
41 
42 	err = os_set_fd_block(*fd_out, 0);
43 	if (err) {
44 		printk("start_io_thread - failed to set nonblocking I/O.\n");
45 		goto out_close;
46 	}
47 
48 	pid = clone(io_thread, (void *) sp, CLONE_FILES | CLONE_VM, NULL);
49 	if(pid < 0){
50 		err = -errno;
51 		printk("start_io_thread - clone failed : errno = %d\n", errno);
52 		goto out_close;
53 	}
54 
55 	return(pid);
56 
57  out_close:
58 	os_close_file(fds[0]);
59 	os_close_file(fds[1]);
60 	kernel_fd = -1;
61 	*fd_out = -1;
62  out:
63 	return err;
64 }
65