ubd_user.c

 1// SPDX-License-Identifier: GPL-2.0
 2/*
 3 * Copyright (C) 2016 Anton Ivanov (aivanov@brocade.com)
 4 * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
 5 * Copyright (C) 2001 Ridgerun,Inc (glonnon@ridgerun.com)
 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
26static struct pollfd kernel_pollfd;
27
28int start_io_thread(struct os_helper_thread **td_out, int *fd_out)
29{
30	int 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	err = os_run_helper_thread(td_out, io_thread, NULL);
51	if (err < 0) {
52		printk("%s - failed to run helper thread, err = %d\n",
53		       __func__, -err);
54		goto out_close;
55	}
56
57	return 0;
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
68int ubd_read_poll(int timeout)
69{
70	kernel_pollfd.events = POLLIN;
71	return poll(&kernel_pollfd, 1, timeout);
72}
73int ubd_write_poll(int timeout)
74{
75	kernel_pollfd.events = POLLOUT;
76	return poll(&kernel_pollfd, 1, timeout);
77}
78