1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
|
/*
* Copyright (C) 2017 - Cambridge Greys Ltd
* Copyright (C) 2011 - 2014 Cisco Systems Inc
* Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
* Licensed under the GPL
*/
#include <stdlib.h>
#include <errno.h>
#include <sys/epoll.h>
#include <signal.h>
#include <string.h>
#include <irq_user.h>
#include <os.h>
#include <um_malloc.h>
/* Epoll support */
static int epollfd = -1;
#define MAX_EPOLL_EVENTS 64
static struct epoll_event epoll_events[MAX_EPOLL_EVENTS];
/* Helper to return an Epoll data pointer from an epoll event structure.
* We need to keep this one on the userspace side to keep includes separate
*/
void *os_epoll_get_data_pointer(int index)
{
return epoll_events[index].data.ptr;
}
/* Helper to compare events versus the events in the epoll structure.
* Same as above - needs to be on the userspace side
*/
int os_epoll_triggered(int index, int events)
{
return epoll_events[index].events & events;
}
/* Helper to set the event mask.
* The event mask is opaque to the kernel side, because it does not have
* access to the right includes/defines for EPOLL constants.
*/
int os_event_mask(int irq_type)
{
if (irq_type == IRQ_READ)
return EPOLLIN | EPOLLPRI | EPOLLERR | EPOLLHUP | EPOLLRDHUP;
if (irq_type == IRQ_WRITE)
return EPOLLOUT;
return 0;
}
/*
* Initial Epoll Setup
*/
int os_setup_epoll(void)
{
epollfd = epoll_create(MAX_EPOLL_EVENTS);
return epollfd;
}
/*
* Helper to run the actual epoll_wait
*/
int os_waiting_for_events_epoll(void)
{
int n, err;
n = epoll_wait(epollfd,
(struct epoll_event *) &epoll_events, MAX_EPOLL_EVENTS, 0);
if (n < 0) {
err = -errno;
if (errno != EINTR)
printk(
UM_KERN_ERR "os_waiting_for_events:"
" epoll returned %d, error = %s\n", n,
strerror(errno)
);
return err;
}
return n;
}
/*
* Helper to add a fd to epoll
*/
int os_add_epoll_fd(int events, int fd, void *data)
{
struct epoll_event event;
int result;
event.data.ptr = data;
event.events = events | EPOLLET;
result = epoll_ctl(epollfd, EPOLL_CTL_ADD, fd, &event);
if ((result) && (errno == EEXIST))
result = os_mod_epoll_fd(events, fd, data);
if (result)
printk("epollctl add err fd %d, %s\n", fd, strerror(errno));
return result;
}
/*
* Helper to mod the fd event mask and/or data backreference
*/
int os_mod_epoll_fd(int events, int fd, void *data)
{
struct epoll_event event;
int result;
event.data.ptr = data;
event.events = events;
result = epoll_ctl(epollfd, EPOLL_CTL_MOD, fd, &event);
if (result)
printk(UM_KERN_ERR
"epollctl mod err fd %d, %s\n", fd, strerror(errno));
return result;
}
/*
* Helper to delete the epoll fd
*/
int os_del_epoll_fd(int fd)
{
struct epoll_event event;
int result;
/* This is quiet as we use this as IO ON/OFF - so it is often
* invoked on a non-existent fd
*/
result = epoll_ctl(epollfd, EPOLL_CTL_DEL, fd, &event);
return result;
}
void os_set_ioignore(void)
{
signal(SIGIO, SIG_IGN);
}
void os_close_epoll_fd(void)
{
/* Needed so we do not leak an fd when rebooting */
os_close_file(epollfd);
}
|
