]> git.proxmox.com Git - qemu.git/blob - migration-unix.c
libqtest: Wait for the right child PID after killing QEMU
[qemu.git] / migration-unix.c
1 /*
2 * QEMU live migration via Unix Domain Sockets
3 *
4 * Copyright Red Hat, Inc. 2009
5 *
6 * Authors:
7 * Chris Lalancette <clalance@redhat.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/sockets.h"
18 #include "migration/migration.h"
19 #include "migration/qemu-file.h"
20 #include "block/block.h"
21
22 //#define DEBUG_MIGRATION_UNIX
23
24 #ifdef DEBUG_MIGRATION_UNIX
25 #define DPRINTF(fmt, ...) \
26 do { printf("migration-unix: " fmt, ## __VA_ARGS__); } while (0)
27 #else
28 #define DPRINTF(fmt, ...) \
29 do { } while (0)
30 #endif
31
32 static int unix_errno(MigrationState *s)
33 {
34 return errno;
35 }
36
37 static int unix_write(MigrationState *s, const void * buf, size_t size)
38 {
39 return write(s->fd, buf, size);
40 }
41
42 static int unix_close(MigrationState *s)
43 {
44 int r = 0;
45 DPRINTF("unix_close\n");
46 if (close(s->fd) < 0) {
47 r = -errno;
48 }
49 return r;
50 }
51
52 static void unix_wait_for_connect(int fd, void *opaque)
53 {
54 MigrationState *s = opaque;
55
56 if (fd < 0) {
57 DPRINTF("migrate connect error\n");
58 s->fd = -1;
59 migrate_fd_error(s);
60 } else {
61 DPRINTF("migrate connect success\n");
62 s->fd = fd;
63 socket_set_block(s->fd);
64 migrate_fd_connect(s);
65 }
66 }
67
68 void unix_start_outgoing_migration(MigrationState *s, const char *path, Error **errp)
69 {
70 s->get_error = unix_errno;
71 s->write = unix_write;
72 s->close = unix_close;
73
74 s->fd = unix_nonblocking_connect(path, unix_wait_for_connect, s, errp);
75 }
76
77 static void unix_accept_incoming_migration(void *opaque)
78 {
79 struct sockaddr_un addr;
80 socklen_t addrlen = sizeof(addr);
81 int s = (intptr_t)opaque;
82 QEMUFile *f;
83 int c;
84
85 do {
86 c = qemu_accept(s, (struct sockaddr *)&addr, &addrlen);
87 } while (c == -1 && errno == EINTR);
88 qemu_set_fd_handler2(s, NULL, NULL, NULL, NULL);
89 close(s);
90
91 DPRINTF("accepted migration\n");
92
93 if (c == -1) {
94 fprintf(stderr, "could not accept migration connection\n");
95 goto out;
96 }
97
98 f = qemu_fopen_socket(c);
99 if (f == NULL) {
100 fprintf(stderr, "could not qemu_fopen socket\n");
101 goto out;
102 }
103
104 process_incoming_migration(f);
105 return;
106
107 out:
108 close(c);
109 }
110
111 void unix_start_incoming_migration(const char *path, Error **errp)
112 {
113 int s;
114
115 s = unix_listen(path, NULL, 0, errp);
116 if (s < 0) {
117 return;
118 }
119
120 qemu_set_fd_handler2(s, NULL, unix_accept_incoming_migration, NULL,
121 (void *)(intptr_t)s);
122 }