linux-user: save auxv length
[qemu.git] / migration-tcp.c
1 /*
2 * QEMU live migration
3 *
4 * Copyright IBM, Corp. 2008
5 *
6 * Authors:
7 * Anthony Liguori <aliguori@us.ibm.com>
8 *
9 * This work is licensed under the terms of the GNU GPL, version 2. See
10 * the COPYING file in the top-level directory.
11 *
12 * Contributions after 2012-01-13 are licensed under the terms of the
13 * GNU GPL, version 2 or (at your option) any later version.
14 */
15
16 #include "qemu-common.h"
17 #include "qemu_socket.h"
18 #include "migration.h"
19 #include "qemu-char.h"
20 #include "buffered_file.h"
21 #include "block.h"
22
23 //#define DEBUG_MIGRATION_TCP
24
25 #ifdef DEBUG_MIGRATION_TCP
26 #define DPRINTF(fmt, ...) \
27 do { printf("migration-tcp: " fmt, ## __VA_ARGS__); } while (0)
28 #else
29 #define DPRINTF(fmt, ...) \
30 do { } while (0)
31 #endif
32
33 static int socket_errno(MigrationState *s)
34 {
35 return socket_error();
36 }
37
38 static int socket_write(MigrationState *s, const void * buf, size_t size)
39 {
40 return send(s->fd, buf, size, 0);
41 }
42
43 static int tcp_close(MigrationState *s)
44 {
45 int r = 0;
46 DPRINTF("tcp_close\n");
47 if (s->fd != -1) {
48 if (close(s->fd) < 0) {
49 r = -errno;
50 }
51 s->fd = -1;
52 }
53 return r;
54 }
55
56 static void tcp_wait_for_connect(void *opaque)
57 {
58 MigrationState *s = opaque;
59 int val, ret;
60 socklen_t valsize = sizeof(val);
61
62 DPRINTF("connect completed\n");
63 do {
64 ret = getsockopt(s->fd, SOL_SOCKET, SO_ERROR, (void *) &val, &valsize);
65 } while (ret == -1 && (socket_error()) == EINTR);
66
67 if (ret < 0) {
68 migrate_fd_error(s);
69 return;
70 }
71
72 qemu_set_fd_handler2(s->fd, NULL, NULL, NULL, NULL);
73
74 if (val == 0)
75 migrate_fd_connect(s);
76 else {
77 DPRINTF("error connecting %d\n", val);
78 migrate_fd_error(s);
79 }
80 }
81
82 int tcp_start_outgoing_migration(MigrationState *s, const char *host_port)
83 {
84 struct sockaddr_in addr;
85 int ret;
86
87 ret = parse_host_port(&addr, host_port);
88 if (ret < 0) {
89 return ret;
90 }
91
92 s->get_error = socket_errno;
93 s->write = socket_write;
94 s->close = tcp_close;
95
96 s->fd = qemu_socket(PF_INET, SOCK_STREAM, 0);
97 if (s->fd == -1) {
98 DPRINTF("Unable to open socket");
99 return -socket_error();
100 }
101
102 socket_set_nonblock(s->fd);
103
104 do {
105 ret = connect(s->fd, (struct sockaddr *)&addr, sizeof(addr));
106 if (ret == -1) {
107 ret = -socket_error();
108 }
109 if (ret == -EINPROGRESS || ret == -EWOULDBLOCK) {
110 qemu_set_fd_handler2(s->fd, NULL, NULL, tcp_wait_for_connect, s);
111 return 0;
112 }
113 } while (ret == -EINTR);
114
115 if (ret < 0) {
116 DPRINTF("connect failed\n");
117 migrate_fd_error(s);
118 return ret;
119 }
120 migrate_fd_connect(s);
121 return 0;
122 }
123
124 static void tcp_accept_incoming_migration(void *opaque)
125 {
126 struct sockaddr_in addr;
127 socklen_t addrlen = sizeof(addr);
128 int s = (intptr_t)opaque;
129 QEMUFile *f;
130 int c;
131
132 do {
133 c = qemu_accept(s, (struct sockaddr *)&addr, &addrlen);
134 } while (c == -1 && socket_error() == EINTR);
135
136 DPRINTF("accepted migration\n");
137
138 if (c == -1) {
139 fprintf(stderr, "could not accept migration connection\n");
140 goto out2;
141 }
142
143 f = qemu_fopen_socket(c);
144 if (f == NULL) {
145 fprintf(stderr, "could not qemu_fopen socket\n");
146 goto out;
147 }
148
149 process_incoming_migration(f);
150 qemu_fclose(f);
151 out:
152 close(c);
153 out2:
154 qemu_set_fd_handler2(s, NULL, NULL, NULL, NULL);
155 close(s);
156 }
157
158 int tcp_start_incoming_migration(const char *host_port)
159 {
160 struct sockaddr_in addr;
161 int val;
162 int s;
163
164 DPRINTF("Attempting to start an incoming migration\n");
165
166 if (parse_host_port(&addr, host_port) < 0) {
167 fprintf(stderr, "invalid host/port combination: %s\n", host_port);
168 return -EINVAL;
169 }
170
171 s = qemu_socket(PF_INET, SOCK_STREAM, 0);
172 if (s == -1) {
173 return -socket_error();
174 }
175
176 val = 1;
177 setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (const char *)&val, sizeof(val));
178
179 if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
180 goto err;
181 }
182 if (listen(s, 1) == -1) {
183 goto err;
184 }
185
186 qemu_set_fd_handler2(s, NULL, tcp_accept_incoming_migration, NULL,
187 (void *)(intptr_t)s);
188
189 return 0;
190
191 err:
192 close(s);
193 return -socket_error();
194 }