xref: /openbmc/linux/arch/um/drivers/ubd_user.c (revision cfbb9be8)
1 /*
2  * Copyright (C) 2016 Anton Ivanov (aivanov@brocade.com)
3  * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
4  * Copyright (C) 2001 Ridgerun,Inc (glonnon@ridgerun.com)
5  * Licensed under the GPL
6  */
7 
8 #include <stddef.h>
9 #include <unistd.h>
10 #include <errno.h>
11 #include <sched.h>
12 #include <signal.h>
13 #include <string.h>
14 #include <netinet/in.h>
15 #include <sys/time.h>
16 #include <sys/socket.h>
17 #include <sys/mman.h>
18 #include <sys/param.h>
19 #include <endian.h>
20 #include <byteswap.h>
21 
22 #include "ubd.h"
23 #include <os.h>
24 #include <poll.h>
25 
26 struct pollfd kernel_pollfd;
27 
28 int start_io_thread(unsigned long sp, int *fd_out)
29 {
30 	int pid, fds[2], err;
31 
32 	err = os_pipe(fds, 1, 1);
33 	if(err < 0){
34 		printk("start_io_thread - os_pipe failed, err = %d\n", -err);
35 		goto out;
36 	}
37 
38 	kernel_fd = fds[0];
39 	kernel_pollfd.fd = kernel_fd;
40 	kernel_pollfd.events = POLLIN;
41 	*fd_out = fds[1];
42 
43 	err = os_set_fd_block(*fd_out, 0);
44 	err = os_set_fd_block(kernel_fd, 0);
45 	if (err) {
46 		printk("start_io_thread - failed to set nonblocking I/O.\n");
47 		goto out_close;
48 	}
49 
50 	pid = clone(io_thread, (void *) sp, CLONE_FILES | CLONE_VM, NULL);
51 	if(pid < 0){
52 		err = -errno;
53 		printk("start_io_thread - clone failed : errno = %d\n", errno);
54 		goto out_close;
55 	}
56 
57 	return(pid);
58 
59  out_close:
60 	os_close_file(fds[0]);
61 	os_close_file(fds[1]);
62 	kernel_fd = -1;
63 	*fd_out = -1;
64  out:
65 	return err;
66 }
67 
68 int ubd_read_poll(int timeout)
69 {
70 	kernel_pollfd.events = POLLIN;
71 	return poll(&kernel_pollfd, 1, timeout);
72 }
73 int ubd_write_poll(int timeout)
74 {
75 	kernel_pollfd.events = POLLOUT;
76 	return poll(&kernel_pollfd, 1, timeout);
77 }
78 
79