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
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
|
/*
* QEMU live migration via Unix Domain Sockets
*
* Copyright Red Hat, Inc. 2009
*
* Authors:
* Chris Lalancette <clalance@redhat.com>
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*
* Contributions after 2012-01-13 are licensed under the terms of the
* GNU GPL, version 2 or (at your option) any later version.
*/
#include "qemu-common.h"
#include "qemu_socket.h"
#include "migration.h"
#include "qemu-char.h"
#include "buffered_file.h"
#include "block.h"
//#define DEBUG_MIGRATION_UNIX
#ifdef DEBUG_MIGRATION_UNIX
#define DPRINTF(fmt, ...) \
do { printf("migration-unix: " fmt, ## __VA_ARGS__); } while (0)
#else
#define DPRINTF(fmt, ...) \
do { } while (0)
#endif
static int unix_errno(MigrationState *s)
{
return errno;
}
static int unix_write(MigrationState *s, const void * buf, size_t size)
{
return write(s->fd, buf, size);
}
static int unix_close(MigrationState *s)
{
int r = 0;
DPRINTF("unix_close\n");
if (s->fd != -1) {
if (close(s->fd) < 0) {
r = -errno;
}
s->fd = -1;
}
return r;
}
static void unix_wait_for_connect(void *opaque)
{
MigrationState *s = opaque;
int val, ret;
socklen_t valsize = sizeof(val);
DPRINTF("connect completed\n");
do {
ret = getsockopt(s->fd, SOL_SOCKET, SO_ERROR, (void *) &val, &valsize);
} while (ret == -1 && errno == EINTR);
if (ret < 0) {
migrate_fd_error(s);
return;
}
qemu_set_fd_handler2(s->fd, NULL, NULL, NULL, NULL);
if (val == 0)
migrate_fd_connect(s);
else {
DPRINTF("error connecting %d\n", val);
migrate_fd_error(s);
}
}
int unix_start_outgoing_migration(MigrationState *s, const char *path)
{
struct sockaddr_un addr;
int ret;
addr.sun_family = AF_UNIX;
snprintf(addr.sun_path, sizeof(addr.sun_path), "%s", path);
s->get_error = unix_errno;
s->write = unix_write;
s->close = unix_close;
s->fd = qemu_socket(PF_UNIX, SOCK_STREAM, 0);
if (s->fd == -1) {
DPRINTF("Unable to open socket");
return -errno;
}
socket_set_nonblock(s->fd);
do {
ret = connect(s->fd, (struct sockaddr *)&addr, sizeof(addr));
if (ret == -1) {
ret = -errno;
}
if (ret == -EINPROGRESS || ret == -EWOULDBLOCK) {
qemu_set_fd_handler2(s->fd, NULL, NULL, unix_wait_for_connect, s);
return 0;
}
} while (ret == -EINTR);
if (ret < 0) {
DPRINTF("connect failed\n");
return ret;
}
migrate_fd_connect(s);
return 0;
}
static void unix_accept_incoming_migration(void *opaque)
{
struct sockaddr_un addr;
socklen_t addrlen = sizeof(addr);
int s = (intptr_t)opaque;
QEMUFile *f;
int c;
do {
c = qemu_accept(s, (struct sockaddr *)&addr, &addrlen);
} while (c == -1 && errno == EINTR);
DPRINTF("accepted migration\n");
if (c == -1) {
fprintf(stderr, "could not accept migration connection\n");
goto out2;
}
f = qemu_fopen_socket(c);
if (f == NULL) {
fprintf(stderr, "could not qemu_fopen socket\n");
goto out;
}
process_incoming_migration(f);
qemu_fclose(f);
out:
close(c);
out2:
qemu_set_fd_handler2(s, NULL, NULL, NULL, NULL);
close(s);
}
int unix_start_incoming_migration(const char *path)
{
struct sockaddr_un addr;
int s;
int ret;
DPRINTF("Attempting to start an incoming migration\n");
s = qemu_socket(PF_UNIX, SOCK_STREAM, 0);
if (s == -1) {
fprintf(stderr, "Could not open unix socket: %s\n", strerror(errno));
return -errno;
}
memset(&addr, 0, sizeof(addr));
addr.sun_family = AF_UNIX;
snprintf(addr.sun_path, sizeof(addr.sun_path), "%s", path);
unlink(addr.sun_path);
if (bind(s, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
ret = -errno;
fprintf(stderr, "bind(unix:%s): %s\n", addr.sun_path, strerror(errno));
goto err;
}
if (listen(s, 1) == -1) {
fprintf(stderr, "listen(unix:%s): %s\n", addr.sun_path,
strerror(errno));
ret = -errno;
goto err;
}
qemu_set_fd_handler2(s, NULL, unix_accept_incoming_migration, NULL,
(void *)(intptr_t)s);
return 0;
err:
close(s);
return ret;
}
|
