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
148
149
150
|
/*
* Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
* Licensed under the GPL
*/
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <signal.h>
#include <string.h>
#include <sys/poll.h>
#include <sys/types.h>
#include <sys/time.h>
#include "user.h"
#include "process.h"
#include "sigio.h"
#include "irq_user.h"
#include "os.h"
#include "um_malloc.h"
/*
* Locked by irq_lock in arch/um/kernel/irq.c. Changed by os_create_pollfd
* and os_free_irq_by_cb, which are called under irq_lock.
*/
static struct pollfd *pollfds = NULL;
static int pollfds_num = 0;
static int pollfds_size = 0;
int os_waiting_for_events(struct irq_fd *active_fds)
{
struct irq_fd *irq_fd;
int i, n, err;
n = poll(pollfds, pollfds_num, 0);
if (n < 0) {
err = -errno;
if (errno != EINTR)
printk("sigio_handler: os_waiting_for_events:"
" poll returned %d, errno = %d\n", n, errno);
return err;
}
if (n == 0)
return 0;
irq_fd = active_fds;
for (i = 0; i < pollfds_num; i++) {
if (pollfds[i].revents != 0) {
irq_fd->current_events = pollfds[i].revents;
pollfds[i].fd = -1;
}
irq_fd = irq_fd->next;
}
return n;
}
int os_create_pollfd(int fd, int events, void *tmp_pfd, int size_tmpfds)
{
if (pollfds_num == pollfds_size) {
if (size_tmpfds <= pollfds_size * sizeof(pollfds[0])) {
/* return min size needed for new pollfds area */
return (pollfds_size + 1) * sizeof(pollfds[0]);
}
if (pollfds != NULL) {
memcpy(tmp_pfd, pollfds,
sizeof(pollfds[0]) * pollfds_size);
/* remove old pollfds */
kfree(pollfds);
}
pollfds = tmp_pfd;
pollfds_size++;
} else
kfree(tmp_pfd); /* remove not used tmp_pfd */
pollfds[pollfds_num] = ((struct pollfd) { .fd = fd,
.events = events,
.revents = 0 });
pollfds_num++;
return 0;
}
void os_free_irq_by_cb(int (*test)(struct irq_fd *, void *), void *arg,
struct irq_fd *active_fds, struct irq_fd ***last_irq_ptr2)
{
struct irq_fd **prev;
int i = 0;
prev = &active_fds;
while (*prev != NULL) {
if ((*test)(*prev, arg)) {
struct irq_fd *old_fd = *prev;
if ((pollfds[i].fd != -1) &&
(pollfds[i].fd != (*prev)->fd)) {
printk("os_free_irq_by_cb - mismatch between "
"active_fds and pollfds, fd %d vs %d\n",
(*prev)->fd, pollfds[i].fd);
goto out;
}
pollfds_num--;
/* This moves the *whole* array after pollfds[i]
* (though it doesn't spot as such)!
*/
memmove(&pollfds[i], &pollfds[i + 1],
(pollfds_num - i) * sizeof(pollfds[0]));
if(*last_irq_ptr2 == &old_fd->next)
*last_irq_ptr2 = prev;
*prev = (*prev)->next;
if(old_fd->type == IRQ_WRITE)
ignore_sigio_fd(old_fd->fd);
kfree(old_fd);
continue;
}
prev = &(*prev)->next;
i++;
}
out:
return;
}
int os_get_pollfd(int i)
{
return pollfds[i].fd;
}
void os_set_pollfd(int i, int fd)
{
pollfds[i].fd = fd;
}
void os_set_ioignore(void)
{
signal(SIGIO, SIG_IGN);
}
void init_irq_signals(int on_sigstack)
{
int flags;
flags = on_sigstack ? SA_ONSTACK : 0;
set_handler(SIGIO, (__sighandler_t) sig_handler, flags | SA_RESTART,
SIGUSR1, SIGIO, SIGWINCH, SIGVTALRM, -1);
signal(SIGWINCH, SIG_IGN);
}
|
