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
|
#include <aio.h>
#include <errno.h>
#include <limits.h>
#include <unistd.h>
#include <string.h>
#include "pthread_impl.h"
struct lio_state {
struct sigevent *sev;
int cnt;
struct aiocb *cbs[];
};
static int lio_wait(struct lio_state *st)
{
int i, err, got_err = 0;
int cnt = st->cnt;
struct aiocb **cbs = st->cbs;
for (;;) {
for (i=0; i<cnt; i++) {
if (!cbs[i]) continue;
err = aio_error(cbs[i]);
if (err==EINPROGRESS)
break;
if (err) got_err=1;
cbs[i] = 0;
}
if (i==cnt) {
if (got_err) {
errno = EIO;
return -1;
}
return 0;
}
if (aio_suspend((void *)cbs, cnt, 0))
return -1;
}
}
static void notify_signal(struct sigevent *sev)
{
siginfo_t si = {
.si_signo = sev->sigev_signo,
.si_value = sev->sigev_value,
.si_code = SI_ASYNCIO,
.si_pid = __pthread_self()->pid,
.si_uid = getuid()
};
__syscall(SYS_rt_sigqueueinfo, si.si_pid, si.si_signo, &si);
}
static void *wait_thread(void *p)
{
struct lio_state *st = p;
struct sigevent *sev = st->sev;
lio_wait(st);
free(st);
switch (sev->sigev_notify) {
case SIGEV_SIGNAL:
notify_signal(sev);
break;
case SIGEV_THREAD:
sev->sigev_notify_function(sev->sigev_value);
break;
}
return 0;
}
int lio_listio(int mode, struct aiocb *restrict const *restrict cbs, int cnt, struct sigevent *restrict sev)
{
int i, ret;
struct lio_state *st=0;
if (cnt < 0) {
errno = EINVAL;
return -1;
}
if (mode == LIO_WAIT || (sev && sev->sigev_notify != SIGEV_NONE)) {
if (!(st = malloc(sizeof *st + cnt*sizeof *cbs))) {
errno = EAGAIN;
return -1;
}
st->cnt = cnt;
st->sev = sev;
memcpy(st->cbs, (void*) cbs, cnt*sizeof *cbs);
}
for (i=0; i<cnt; i++) {
if (!cbs[i]) continue;
switch (cbs[i]->aio_lio_opcode) {
case LIO_READ:
ret = aio_read(cbs[i]);
break;
case LIO_WRITE:
ret = aio_write(cbs[i]);
break;
default:
continue;
}
if (ret) {
free(st);
errno = EAGAIN;
return -1;
}
}
if (mode == LIO_WAIT) {
ret = lio_wait(st);
free(st);
return ret;
}
if (st) {
pthread_attr_t a;
sigset_t set;
pthread_t td;
if (sev->sigev_notify == SIGEV_THREAD) {
if (sev->sigev_notify_attributes)
a = *sev->sigev_notify_attributes;
else
pthread_attr_init(&a);
} else {
pthread_attr_init(&a);
pthread_attr_setstacksize(&a, PAGE_SIZE);
pthread_attr_setguardsize(&a, 0);
}
pthread_attr_setdetachstate(&a, PTHREAD_CREATE_DETACHED);
sigfillset(&set);
pthread_sigmask(SIG_BLOCK, &set, &set);
if (pthread_create(&td, &a, wait_thread, st)) {
free(st);
errno = EAGAIN;
return -1;
}
pthread_sigmask(SIG_SETMASK, &set, 0);
}
return 0;
}
|
