tcg-s390: correctly detect s390 with a 64-bit kernel
[qemu.git] / migration.c
blobfbf23399e5e855de7bbdd4b78d8af4c97801dcef
1 /*
2 * QEMU live migration
4 * Copyright IBM, Corp. 2008
6 * Authors:
7 * Anthony Liguori <aliguori@us.ibm.com>
9 * This work is licensed under the terms of the GNU GPL, version 2. See
10 * the COPYING file in the top-level directory.
14 #include "qemu-common.h"
15 #include "migration.h"
16 #include "monitor.h"
17 #include "buffered_file.h"
18 #include "sysemu.h"
19 #include "block.h"
20 #include "qemu_socket.h"
21 #include "block-migration.h"
22 #include "qemu-objects.h"
24 //#define DEBUG_MIGRATION
26 #ifdef DEBUG_MIGRATION
27 #define DPRINTF(fmt, ...) \
28 do { printf("migration: " fmt, ## __VA_ARGS__); } while (0)
29 #else
30 #define DPRINTF(fmt, ...) \
31 do { } while (0)
32 #endif
34 /* Migration speed throttling */
35 static uint32_t max_throttle = (32 << 20);
37 static MigrationState *current_migration;
39 void qemu_start_incoming_migration(const char *uri)
41 const char *p;
43 if (strstart(uri, "tcp:", &p))
44 tcp_start_incoming_migration(p);
45 #if !defined(WIN32)
46 else if (strstart(uri, "exec:", &p))
47 exec_start_incoming_migration(p);
48 else if (strstart(uri, "unix:", &p))
49 unix_start_incoming_migration(p);
50 else if (strstart(uri, "fd:", &p))
51 fd_start_incoming_migration(p);
52 #endif
53 else
54 fprintf(stderr, "unknown migration protocol: %s\n", uri);
57 int do_migrate(Monitor *mon, const QDict *qdict, QObject **ret_data)
59 MigrationState *s = NULL;
60 const char *p;
61 int detach = qdict_get_int(qdict, "detach");
62 const char *uri = qdict_get_str(qdict, "uri");
64 if (current_migration &&
65 current_migration->get_status(current_migration) == MIG_STATE_ACTIVE) {
66 monitor_printf(mon, "migration already in progress\n");
67 return -1;
70 if (strstart(uri, "tcp:", &p)) {
71 s = tcp_start_outgoing_migration(mon, p, max_throttle, detach,
72 (int)qdict_get_int(qdict, "blk"),
73 (int)qdict_get_int(qdict, "inc"));
74 #if !defined(WIN32)
75 } else if (strstart(uri, "exec:", &p)) {
76 s = exec_start_outgoing_migration(mon, p, max_throttle, detach,
77 (int)qdict_get_int(qdict, "blk"),
78 (int)qdict_get_int(qdict, "inc"));
79 } else if (strstart(uri, "unix:", &p)) {
80 s = unix_start_outgoing_migration(mon, p, max_throttle, detach,
81 (int)qdict_get_int(qdict, "blk"),
82 (int)qdict_get_int(qdict, "inc"));
83 } else if (strstart(uri, "fd:", &p)) {
84 s = fd_start_outgoing_migration(mon, p, max_throttle, detach,
85 (int)qdict_get_int(qdict, "blk"),
86 (int)qdict_get_int(qdict, "inc"));
87 #endif
88 } else {
89 monitor_printf(mon, "unknown migration protocol: %s\n", uri);
90 return -1;
93 if (s == NULL) {
94 monitor_printf(mon, "migration failed\n");
95 return -1;
98 if (current_migration) {
99 current_migration->release(current_migration);
102 current_migration = s;
103 return 0;
106 int do_migrate_cancel(Monitor *mon, const QDict *qdict, QObject **ret_data)
108 MigrationState *s = current_migration;
110 if (s)
111 s->cancel(s);
113 return 0;
116 int do_migrate_set_speed(Monitor *mon, const QDict *qdict, QObject **ret_data)
118 double d;
119 FdMigrationState *s;
121 d = qdict_get_double(qdict, "value");
122 d = MAX(0, MIN(UINT32_MAX, d));
123 max_throttle = d;
125 s = migrate_to_fms(current_migration);
126 if (s && s->file) {
127 qemu_file_set_rate_limit(s->file, max_throttle);
130 return 0;
133 /* amount of nanoseconds we are willing to wait for migration to be down.
134 * the choice of nanoseconds is because it is the maximum resolution that
135 * get_clock() can achieve. It is an internal measure. All user-visible
136 * units must be in seconds */
137 static uint64_t max_downtime = 30000000;
139 uint64_t migrate_max_downtime(void)
141 return max_downtime;
144 int do_migrate_set_downtime(Monitor *mon, const QDict *qdict,
145 QObject **ret_data)
147 double d;
149 d = qdict_get_double(qdict, "value") * 1e9;
150 d = MAX(0, MIN(UINT64_MAX, d));
151 max_downtime = (uint64_t)d;
153 return 0;
156 static void migrate_print_status(Monitor *mon, const char *name,
157 const QDict *status_dict)
159 QDict *qdict;
161 qdict = qobject_to_qdict(qdict_get(status_dict, name));
163 monitor_printf(mon, "transferred %s: %" PRIu64 " kbytes\n", name,
164 qdict_get_int(qdict, "transferred") >> 10);
165 monitor_printf(mon, "remaining %s: %" PRIu64 " kbytes\n", name,
166 qdict_get_int(qdict, "remaining") >> 10);
167 monitor_printf(mon, "total %s: %" PRIu64 " kbytes\n", name,
168 qdict_get_int(qdict, "total") >> 10);
171 void do_info_migrate_print(Monitor *mon, const QObject *data)
173 QDict *qdict;
175 qdict = qobject_to_qdict(data);
177 monitor_printf(mon, "Migration status: %s\n",
178 qdict_get_str(qdict, "status"));
180 if (qdict_haskey(qdict, "ram")) {
181 migrate_print_status(mon, "ram", qdict);
184 if (qdict_haskey(qdict, "disk")) {
185 migrate_print_status(mon, "disk", qdict);
189 static void migrate_put_status(QDict *qdict, const char *name,
190 uint64_t trans, uint64_t rem, uint64_t total)
192 QObject *obj;
194 obj = qobject_from_jsonf("{ 'transferred': %" PRId64 ", "
195 "'remaining': %" PRId64 ", "
196 "'total': %" PRId64 " }", trans, rem, total);
197 qdict_put_obj(qdict, name, obj);
200 void do_info_migrate(Monitor *mon, QObject **ret_data)
202 QDict *qdict;
203 MigrationState *s = current_migration;
205 if (s) {
206 switch (s->get_status(s)) {
207 case MIG_STATE_ACTIVE:
208 qdict = qdict_new();
209 qdict_put(qdict, "status", qstring_from_str("active"));
211 migrate_put_status(qdict, "ram", ram_bytes_transferred(),
212 ram_bytes_remaining(), ram_bytes_total());
214 if (blk_mig_active()) {
215 migrate_put_status(qdict, "disk", blk_mig_bytes_transferred(),
216 blk_mig_bytes_remaining(),
217 blk_mig_bytes_total());
220 *ret_data = QOBJECT(qdict);
221 break;
222 case MIG_STATE_COMPLETED:
223 *ret_data = qobject_from_jsonf("{ 'status': 'completed' }");
224 break;
225 case MIG_STATE_ERROR:
226 *ret_data = qobject_from_jsonf("{ 'status': 'failed' }");
227 break;
228 case MIG_STATE_CANCELLED:
229 *ret_data = qobject_from_jsonf("{ 'status': 'cancelled' }");
230 break;
235 /* shared migration helpers */
237 void migrate_fd_monitor_suspend(FdMigrationState *s, Monitor *mon)
239 s->mon = mon;
240 if (monitor_suspend(mon) == 0) {
241 DPRINTF("suspending monitor\n");
242 } else {
243 monitor_printf(mon, "terminal does not allow synchronous "
244 "migration, continuing detached\n");
248 void migrate_fd_error(FdMigrationState *s)
250 DPRINTF("setting error state\n");
251 s->state = MIG_STATE_ERROR;
252 migrate_fd_cleanup(s);
255 int migrate_fd_cleanup(FdMigrationState *s)
257 int ret = 0;
259 qemu_set_fd_handler2(s->fd, NULL, NULL, NULL, NULL);
261 if (s->file) {
262 DPRINTF("closing file\n");
263 if (qemu_fclose(s->file) != 0) {
264 ret = -1;
266 s->file = NULL;
269 if (s->fd != -1)
270 close(s->fd);
272 /* Don't resume monitor until we've flushed all of the buffers */
273 if (s->mon) {
274 monitor_resume(s->mon);
277 s->fd = -1;
279 return ret;
282 void migrate_fd_put_notify(void *opaque)
284 FdMigrationState *s = opaque;
286 qemu_set_fd_handler2(s->fd, NULL, NULL, NULL, NULL);
287 qemu_file_put_notify(s->file);
290 ssize_t migrate_fd_put_buffer(void *opaque, const void *data, size_t size)
292 FdMigrationState *s = opaque;
293 ssize_t ret;
295 do {
296 ret = s->write(s, data, size);
297 } while (ret == -1 && ((s->get_error(s)) == EINTR));
299 if (ret == -1)
300 ret = -(s->get_error(s));
302 if (ret == -EAGAIN)
303 qemu_set_fd_handler2(s->fd, NULL, NULL, migrate_fd_put_notify, s);
305 return ret;
308 void migrate_fd_connect(FdMigrationState *s)
310 int ret;
312 s->file = qemu_fopen_ops_buffered(s,
313 s->bandwidth_limit,
314 migrate_fd_put_buffer,
315 migrate_fd_put_ready,
316 migrate_fd_wait_for_unfreeze,
317 migrate_fd_close);
319 DPRINTF("beginning savevm\n");
320 ret = qemu_savevm_state_begin(s->mon, s->file, s->mig_state.blk,
321 s->mig_state.shared);
322 if (ret < 0) {
323 DPRINTF("failed, %d\n", ret);
324 migrate_fd_error(s);
325 return;
328 migrate_fd_put_ready(s);
331 void migrate_fd_put_ready(void *opaque)
333 FdMigrationState *s = opaque;
335 if (s->state != MIG_STATE_ACTIVE) {
336 DPRINTF("put_ready returning because of non-active state\n");
337 return;
340 DPRINTF("iterate\n");
341 if (qemu_savevm_state_iterate(s->mon, s->file) == 1) {
342 int state;
343 int old_vm_running = vm_running;
345 DPRINTF("done iterating\n");
346 vm_stop(0);
348 qemu_aio_flush();
349 bdrv_flush_all();
350 if ((qemu_savevm_state_complete(s->mon, s->file)) < 0) {
351 if (old_vm_running) {
352 vm_start();
354 state = MIG_STATE_ERROR;
355 } else {
356 state = MIG_STATE_COMPLETED;
358 if (migrate_fd_cleanup(s) < 0) {
359 if (old_vm_running) {
360 vm_start();
362 state = MIG_STATE_ERROR;
364 s->state = state;
368 int migrate_fd_get_status(MigrationState *mig_state)
370 FdMigrationState *s = migrate_to_fms(mig_state);
371 return s->state;
374 void migrate_fd_cancel(MigrationState *mig_state)
376 FdMigrationState *s = migrate_to_fms(mig_state);
378 if (s->state != MIG_STATE_ACTIVE)
379 return;
381 DPRINTF("cancelling migration\n");
383 s->state = MIG_STATE_CANCELLED;
384 qemu_savevm_state_cancel(s->mon, s->file);
386 migrate_fd_cleanup(s);
389 void migrate_fd_release(MigrationState *mig_state)
391 FdMigrationState *s = migrate_to_fms(mig_state);
393 DPRINTF("releasing state\n");
395 if (s->state == MIG_STATE_ACTIVE) {
396 s->state = MIG_STATE_CANCELLED;
397 migrate_fd_cleanup(s);
399 free(s);
402 void migrate_fd_wait_for_unfreeze(void *opaque)
404 FdMigrationState *s = opaque;
405 int ret;
407 DPRINTF("wait for unfreeze\n");
408 if (s->state != MIG_STATE_ACTIVE)
409 return;
411 do {
412 fd_set wfds;
414 FD_ZERO(&wfds);
415 FD_SET(s->fd, &wfds);
417 ret = select(s->fd + 1, NULL, &wfds, NULL, NULL);
418 } while (ret == -1 && (s->get_error(s)) == EINTR);
421 int migrate_fd_close(void *opaque)
423 FdMigrationState *s = opaque;
425 qemu_set_fd_handler2(s->fd, NULL, NULL, NULL, NULL);
426 return s->close(s);