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1 | dcc38d1c | Marcelo Tosatti | /*
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2 | dcc38d1c | Marcelo Tosatti | * signalfd/eventfd compatibility
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3 | dcc38d1c | Marcelo Tosatti | *
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4 | dcc38d1c | Marcelo Tosatti | * Copyright IBM, Corp. 2008
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5 | dcc38d1c | Marcelo Tosatti | *
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6 | dcc38d1c | Marcelo Tosatti | * Authors:
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7 | dcc38d1c | Marcelo Tosatti | * Anthony Liguori <aliguori@us.ibm.com>
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8 | dcc38d1c | Marcelo Tosatti | *
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9 | dcc38d1c | Marcelo Tosatti | * This work is licensed under the terms of the GNU GPL, version 2. See
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10 | dcc38d1c | Marcelo Tosatti | * the COPYING file in the top-level directory.
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11 | dcc38d1c | Marcelo Tosatti | *
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12 | dcc38d1c | Marcelo Tosatti | */
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13 | dcc38d1c | Marcelo Tosatti | |
14 | dcc38d1c | Marcelo Tosatti | #include "qemu-common.h" |
15 | dcc38d1c | Marcelo Tosatti | #include "compatfd.h" |
16 | dcc38d1c | Marcelo Tosatti | |
17 | dcc38d1c | Marcelo Tosatti | #include <sys/syscall.h> |
18 | dcc38d1c | Marcelo Tosatti | #include <pthread.h> |
19 | dcc38d1c | Marcelo Tosatti | |
20 | dcc38d1c | Marcelo Tosatti | struct sigfd_compat_info
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21 | dcc38d1c | Marcelo Tosatti | { |
22 | dcc38d1c | Marcelo Tosatti | sigset_t mask; |
23 | dcc38d1c | Marcelo Tosatti | int fd;
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24 | dcc38d1c | Marcelo Tosatti | }; |
25 | dcc38d1c | Marcelo Tosatti | |
26 | dcc38d1c | Marcelo Tosatti | static void *sigwait_compat(void *opaque) |
27 | dcc38d1c | Marcelo Tosatti | { |
28 | dcc38d1c | Marcelo Tosatti | struct sigfd_compat_info *info = opaque;
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29 | dcc38d1c | Marcelo Tosatti | sigset_t all; |
30 | dcc38d1c | Marcelo Tosatti | |
31 | dcc38d1c | Marcelo Tosatti | sigfillset(&all); |
32 | 09716e45 | Alexander Graf | pthread_sigmask(SIG_BLOCK, &all, NULL);
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33 | dcc38d1c | Marcelo Tosatti | |
34 | 30faaf70 | Tristan Gingold | while (1) { |
35 | 30faaf70 | Tristan Gingold | int sig;
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36 | 30faaf70 | Tristan Gingold | int err;
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37 | dcc38d1c | Marcelo Tosatti | |
38 | 30faaf70 | Tristan Gingold | err = sigwait(&info->mask, &sig); |
39 | 30faaf70 | Tristan Gingold | if (err != 0) { |
40 | 30faaf70 | Tristan Gingold | if (errno == EINTR) {
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41 | 30faaf70 | Tristan Gingold | continue;
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42 | 30faaf70 | Tristan Gingold | } else {
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43 | 30faaf70 | Tristan Gingold | return NULL; |
44 | 30faaf70 | Tristan Gingold | } |
45 | 30faaf70 | Tristan Gingold | } else {
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46 | 30faaf70 | Tristan Gingold | struct qemu_signalfd_siginfo buffer;
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47 | dcc38d1c | Marcelo Tosatti | size_t offset = 0;
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48 | dcc38d1c | Marcelo Tosatti | |
49 | 30faaf70 | Tristan Gingold | memset(&buffer, 0, sizeof(buffer)); |
50 | 30faaf70 | Tristan Gingold | buffer.ssi_signo = sig; |
51 | 30faaf70 | Tristan Gingold | |
52 | dcc38d1c | Marcelo Tosatti | while (offset < sizeof(buffer)) { |
53 | dcc38d1c | Marcelo Tosatti | ssize_t len; |
54 | dcc38d1c | Marcelo Tosatti | |
55 | 30faaf70 | Tristan Gingold | len = write(info->fd, (char *)&buffer + offset,
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56 | dcc38d1c | Marcelo Tosatti | sizeof(buffer) - offset);
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57 | dcc38d1c | Marcelo Tosatti | if (len == -1 && errno == EINTR) |
58 | dcc38d1c | Marcelo Tosatti | continue;
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59 | dcc38d1c | Marcelo Tosatti | |
60 | dcc38d1c | Marcelo Tosatti | if (len <= 0) { |
61 | 30faaf70 | Tristan Gingold | return NULL; |
62 | dcc38d1c | Marcelo Tosatti | } |
63 | dcc38d1c | Marcelo Tosatti | |
64 | dcc38d1c | Marcelo Tosatti | offset += len; |
65 | dcc38d1c | Marcelo Tosatti | } |
66 | dcc38d1c | Marcelo Tosatti | } |
67 | 30faaf70 | Tristan Gingold | } |
68 | dcc38d1c | Marcelo Tosatti | } |
69 | dcc38d1c | Marcelo Tosatti | |
70 | dcc38d1c | Marcelo Tosatti | static int qemu_signalfd_compat(const sigset_t *mask) |
71 | dcc38d1c | Marcelo Tosatti | { |
72 | dcc38d1c | Marcelo Tosatti | pthread_attr_t attr; |
73 | dcc38d1c | Marcelo Tosatti | pthread_t tid; |
74 | dcc38d1c | Marcelo Tosatti | struct sigfd_compat_info *info;
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75 | dcc38d1c | Marcelo Tosatti | int fds[2]; |
76 | dcc38d1c | Marcelo Tosatti | |
77 | dcc38d1c | Marcelo Tosatti | info = malloc(sizeof(*info));
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78 | dcc38d1c | Marcelo Tosatti | if (info == NULL) { |
79 | dcc38d1c | Marcelo Tosatti | errno = ENOMEM; |
80 | dcc38d1c | Marcelo Tosatti | return -1; |
81 | dcc38d1c | Marcelo Tosatti | } |
82 | dcc38d1c | Marcelo Tosatti | |
83 | dcc38d1c | Marcelo Tosatti | if (pipe(fds) == -1) { |
84 | dcc38d1c | Marcelo Tosatti | free(info); |
85 | dcc38d1c | Marcelo Tosatti | return -1; |
86 | dcc38d1c | Marcelo Tosatti | } |
87 | dcc38d1c | Marcelo Tosatti | |
88 | dcc38d1c | Marcelo Tosatti | qemu_set_cloexec(fds[0]);
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89 | dcc38d1c | Marcelo Tosatti | qemu_set_cloexec(fds[1]);
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90 | dcc38d1c | Marcelo Tosatti | |
91 | dcc38d1c | Marcelo Tosatti | memcpy(&info->mask, mask, sizeof(*mask));
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92 | dcc38d1c | Marcelo Tosatti | info->fd = fds[1];
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93 | dcc38d1c | Marcelo Tosatti | |
94 | dcc38d1c | Marcelo Tosatti | pthread_attr_init(&attr); |
95 | dcc38d1c | Marcelo Tosatti | pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); |
96 | dcc38d1c | Marcelo Tosatti | |
97 | dcc38d1c | Marcelo Tosatti | pthread_create(&tid, &attr, sigwait_compat, info); |
98 | dcc38d1c | Marcelo Tosatti | |
99 | dcc38d1c | Marcelo Tosatti | pthread_attr_destroy(&attr); |
100 | dcc38d1c | Marcelo Tosatti | |
101 | dcc38d1c | Marcelo Tosatti | return fds[0]; |
102 | dcc38d1c | Marcelo Tosatti | } |
103 | dcc38d1c | Marcelo Tosatti | |
104 | dcc38d1c | Marcelo Tosatti | int qemu_signalfd(const sigset_t *mask) |
105 | dcc38d1c | Marcelo Tosatti | { |
106 | dcc38d1c | Marcelo Tosatti | #if defined(CONFIG_SIGNALFD)
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107 | dcc38d1c | Marcelo Tosatti | int ret;
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108 | dcc38d1c | Marcelo Tosatti | |
109 | dcc38d1c | Marcelo Tosatti | ret = syscall(SYS_signalfd, -1, mask, _NSIG / 8); |
110 | dcc38d1c | Marcelo Tosatti | if (ret != -1) { |
111 | dcc38d1c | Marcelo Tosatti | qemu_set_cloexec(ret); |
112 | dcc38d1c | Marcelo Tosatti | return ret;
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113 | dcc38d1c | Marcelo Tosatti | } |
114 | dcc38d1c | Marcelo Tosatti | #endif
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115 | dcc38d1c | Marcelo Tosatti | |
116 | dcc38d1c | Marcelo Tosatti | return qemu_signalfd_compat(mask);
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117 | dcc38d1c | Marcelo Tosatti | } |
118 | d25f89c9 | Jan Kiszka | |
119 | d25f89c9 | Jan Kiszka | bool qemu_signalfd_available(void) |
120 | d25f89c9 | Jan Kiszka | { |
121 | d25f89c9 | Jan Kiszka | #ifdef CONFIG_SIGNALFD
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122 | 7f84c127 | Peter Maydell | sigset_t mask; |
123 | 7f84c127 | Peter Maydell | int fd;
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124 | 7f84c127 | Peter Maydell | bool ok;
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125 | 7f84c127 | Peter Maydell | sigemptyset(&mask); |
126 | d25f89c9 | Jan Kiszka | errno = 0;
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127 | 7f84c127 | Peter Maydell | fd = syscall(SYS_signalfd, -1, &mask, _NSIG / 8); |
128 | 7f84c127 | Peter Maydell | ok = (errno != ENOSYS); |
129 | 7f84c127 | Peter Maydell | if (fd >= 0) { |
130 | 7f84c127 | Peter Maydell | close(fd); |
131 | 7f84c127 | Peter Maydell | } |
132 | 7f84c127 | Peter Maydell | return ok;
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133 | d25f89c9 | Jan Kiszka | #else
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134 | d25f89c9 | Jan Kiszka | return false; |
135 | d25f89c9 | Jan Kiszka | #endif
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136 | d25f89c9 | Jan Kiszka | } |