aboutsummaryrefslogtreecommitdiff
path: root/migration-tcp.c
blob: 7a87a1edaf0d680c06b8f54c57a119dd6bfcf4e7 (plain)
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
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
/*
 * QEMU live migration
 *
 * Copyright IBM, Corp. 2008
 *
 * Authors:
 *  Anthony Liguori   <aliguori@us.ibm.com>
 *
 * This work is licensed under the terms of the GNU GPL, version 2.  See
 * the COPYING file in the top-level directory.
 *
 */

#include "qemu-common.h"
#include "qemu_socket.h"
#include "migration.h"
#include "qemu-char.h"
#include "sysemu.h"
#include "buffered_file.h"
#include "block.h"

//#define DEBUG_MIGRATION_TCP

#ifdef DEBUG_MIGRATION_TCP
#define dprintf(fmt, ...) \
    do { printf("migration-tcp: " fmt, ## __VA_ARGS__); } while (0)
#else
#define dprintf(fmt, ...) \
    do { } while (0)
#endif

static int socket_errno(FdMigrationState *s)
{
    return socket_error();
}

static int socket_write(FdMigrationState *s, const void * buf, size_t size)
{
    return send(s->fd, buf, size, 0);
}

static int tcp_close(FdMigrationState *s)
{
    dprintf("tcp_close\n");
    if (s->fd != -1) {
        close(s->fd);
        s->fd = -1;
    }
    return 0;
}


static void tcp_wait_for_connect(void *opaque)
{
    FdMigrationState *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 && (s->get_error(s)) == 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);
    }
}

MigrationState *tcp_start_outgoing_migration(const char *host_port,
                                             int64_t bandwidth_limit,
                                             int detach)
{
    struct sockaddr_in addr;
    FdMigrationState *s;
    int ret;

    if (parse_host_port(&addr, host_port) < 0)
        return NULL;

    s = qemu_mallocz(sizeof(*s));

    s->get_error = socket_errno;
    s->write = socket_write;
    s->close = tcp_close;
    s->mig_state.cancel = migrate_fd_cancel;
    s->mig_state.get_status = migrate_fd_get_status;
    s->mig_state.release = migrate_fd_release;

    s->state = MIG_STATE_ACTIVE;
    s->mon_resume = NULL;
    s->bandwidth_limit = bandwidth_limit;
    s->fd = socket(PF_INET, SOCK_STREAM, 0);
    if (s->fd == -1) {
        qemu_free(s);
        return NULL;
    }

    socket_set_nonblock(s->fd);

    if (!detach)
        migrate_fd_monitor_suspend(s);

    do {
        ret = connect(s->fd, (struct sockaddr *)&addr, sizeof(addr));
        if (ret == -1)
            ret = -(s->get_error(s));

        if (ret == -EINPROGRESS || ret == -EWOULDBLOCK)
            qemu_set_fd_handler2(s->fd, NULL, NULL, tcp_wait_for_connect, s);
    } while (ret == -EINTR);

    if (ret < 0 && ret != -EINPROGRESS && ret != -EWOULDBLOCK) {
        dprintf("connect failed\n");
        close(s->fd);
        qemu_free(s);
        return NULL;
    } else if (ret >= 0)
        migrate_fd_connect(s);

    return &s->mig_state;
}

static void tcp_accept_incoming_migration(void *opaque)
{
    struct sockaddr_in addr;
    socklen_t addrlen = sizeof(addr);
    int s = (unsigned long)opaque;
    QEMUFile *f;
    int c, ret;

    do {
        c = accept(s, (struct sockaddr *)&addr, &addrlen);
    } while (c == -1 && socket_error() == EINTR);

    dprintf("accepted migration\n");

    if (c == -1) {
        fprintf(stderr, "could not accept migration connection\n");
        return;
    }

    f = qemu_fopen_socket(c);
    if (f == NULL) {
        fprintf(stderr, "could not qemu_fopen socket\n");
        goto out;
    }

    ret = qemu_loadvm_state(f);
    if (ret < 0) {
        fprintf(stderr, "load of migration failed\n");
        goto out_fopen;
    }
    qemu_announce_self();
    dprintf("successfully loaded vm state\n");

    /* we've successfully migrated, close the server socket */
    qemu_set_fd_handler2(s, NULL, NULL, NULL, NULL);
    close(s);

out_fopen:
    qemu_fclose(f);
out:
    close(c);
}

int tcp_start_incoming_migration(const char *host_port)
{
    struct sockaddr_in addr;
    int val;
    int s;

    if (parse_host_port(&addr, host_port) < 0) {
        fprintf(stderr, "invalid host/port combination: %s\n", host_port);
        return -EINVAL;
    }

    s = socket(PF_INET, SOCK_STREAM, 0);
    if (s == -1)
        return -socket_error();

    val = 1;
    setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (const char *)&val, sizeof(val));

    if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) == -1)
        goto err;

    if (listen(s, 1) == -1)
        goto err;

    qemu_set_fd_handler2(s, NULL, tcp_accept_incoming_migration, NULL,
                         (void *)(unsigned long)s);

    return 0;

err:
    close(s);
    return -socket_error();
}