xref: /linux/arch/um/drivers/ubd_user.c (revision 643d1f7fe3aa12c8bdea6fa5b4ba874ff6dd601d)
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 "kern_util.h"
20 #include "user.h"
21 #include "ubd_user.h"
22 #include "os.h"
23 #include "cow.h"
24 
25 #include <endian.h>
26 #include <byteswap.h>
27 
28 void ignore_sigwinch_sig(void)
29 {
30 	signal(SIGWINCH, SIG_IGN);
31 }
32 
33 int start_io_thread(unsigned long sp, int *fd_out)
34 {
35 	int pid, fds[2], err;
36 
37 	err = os_pipe(fds, 1, 1);
38 	if(err < 0){
39 		printk("start_io_thread - os_pipe failed, err = %d\n", -err);
40 		goto out;
41 	}
42 
43 	kernel_fd = fds[0];
44 	*fd_out = fds[1];
45 
46 	err = os_set_fd_block(*fd_out, 0);
47 	if (err) {
48 		printk("start_io_thread - failed to set nonblocking I/O.\n");
49 		goto out_close;
50 	}
51 
52 	pid = clone(io_thread, (void *) sp, CLONE_FILES | CLONE_VM, NULL);
53 	if(pid < 0){
54 		err = -errno;
55 		printk("start_io_thread - clone failed : errno = %d\n", errno);
56 		goto out_close;
57 	}
58 
59 	return(pid);
60 
61  out_close:
62 	os_close_file(fds[0]);
63 	os_close_file(fds[1]);
64 	kernel_fd = -1;
65 	*fd_out = -1;
66  out:
67 	return err;
68 }
69