Disable preadv/pwritev support
[qemu-kvm/fedora.git] / migration.c
blobee64d410e16096a366a1507ab7dadf651e8d6e5e
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"
22 //#define DEBUG_MIGRATION
24 #ifdef DEBUG_MIGRATION
25 #define dprintf(fmt, ...) \
26 do { printf("migration: " fmt, ## __VA_ARGS__); } while (0)
27 #else
28 #define dprintf(fmt, ...) \
29 do { } while (0)
30 #endif
32 /* Migration speed throttling */
33 static uint32_t max_throttle = (32 << 20);
35 static MigrationState *current_migration;
37 void qemu_start_incoming_migration(const char *uri)
39 const char *p;
41 if (strstart(uri, "tcp:", &p))
42 tcp_start_incoming_migration(p);
43 #if !defined(WIN32)
44 else if (strstart(uri, "exec:", &p))
45 exec_start_incoming_migration(p);
46 #endif
47 else
48 fprintf(stderr, "unknown migration protocol: %s\n", uri);
51 void do_migrate(Monitor *mon, int detach, const char *uri)
53 MigrationState *s = NULL;
54 const char *p;
56 if (strstart(uri, "tcp:", &p))
57 s = tcp_start_outgoing_migration(p, max_throttle, detach);
58 #if !defined(WIN32)
59 else if (strstart(uri, "exec:", &p))
60 s = exec_start_outgoing_migration(p, max_throttle, detach);
61 #endif
62 else
63 monitor_printf(mon, "unknown migration protocol: %s\n", uri);
65 if (s == NULL)
66 monitor_printf(mon, "migration failed\n");
67 else {
68 if (current_migration)
69 current_migration->release(current_migration);
71 current_migration = s;
75 void do_migrate_cancel(Monitor *mon)
77 MigrationState *s = current_migration;
79 if (s)
80 s->cancel(s);
83 void do_migrate_set_speed(Monitor *mon, const char *value)
85 double d;
86 char *ptr;
87 FdMigrationState *s;
89 d = strtod(value, &ptr);
90 switch (*ptr) {
91 case 'G': case 'g':
92 d *= 1024;
93 case 'M': case 'm':
94 d *= 1024;
95 case 'K': case 'k':
96 d *= 1024;
97 default:
98 break;
101 max_throttle = (uint32_t)d;
102 s = migrate_to_fms(current_migration);
104 if (s) {
105 qemu_file_set_rate_limit(s->file, max_throttle);
110 /* amount of nanoseconds we are willing to wait for migration to be down.
111 * the choice of nanoseconds is because it is the maximum resolution that
112 * get_clock() can achieve. It is an internal measure. All user-visible
113 * units must be in seconds */
114 static uint64_t max_downtime = 30000000;
116 uint64_t migrate_max_downtime(void)
118 return max_downtime;
121 void do_migrate_set_downtime(Monitor *mon, const char *value)
123 char *ptr;
124 double d;
126 d = strtod(value, &ptr);
127 if (!strcmp(ptr,"ms")) {
128 d *= 1000000;
129 } else if (!strcmp(ptr,"us")) {
130 d *= 1000;
131 } else if (!strcmp(ptr,"ns")) {
132 } else {
133 /* all else considered to be seconds */
134 d *= 1000000000;
137 max_downtime = (uint64_t)d;
140 void do_info_migrate(Monitor *mon)
142 MigrationState *s = current_migration;
144 if (s) {
145 monitor_printf(mon, "Migration status: ");
146 switch (s->get_status(s)) {
147 case MIG_STATE_ACTIVE:
148 monitor_printf(mon, "active\n");
149 monitor_printf(mon, "transferred ram: %" PRIu64 " kbytes\n", ram_bytes_transferred() >> 10);
150 monitor_printf(mon, "remaining ram: %" PRIu64 " kbytes\n", ram_bytes_remaining() >> 10);
151 monitor_printf(mon, "total ram: %" PRIu64 " kbytes\n", ram_bytes_total() >> 10);
152 break;
153 case MIG_STATE_COMPLETED:
154 monitor_printf(mon, "completed\n");
155 break;
156 case MIG_STATE_ERROR:
157 monitor_printf(mon, "failed\n");
158 break;
159 case MIG_STATE_CANCELLED:
160 monitor_printf(mon, "cancelled\n");
161 break;
166 /* shared migration helpers */
168 void migrate_fd_monitor_suspend(FdMigrationState *s)
170 s->mon_resume = cur_mon;
171 if (monitor_suspend(cur_mon) == 0)
172 dprintf("suspending monitor\n");
173 else
174 monitor_printf(cur_mon, "terminal does not allow synchronous "
175 "migration, continuing detached\n");
178 void migrate_fd_error(FdMigrationState *s)
180 dprintf("setting error state\n");
181 s->state = MIG_STATE_ERROR;
182 migrate_fd_cleanup(s);
185 void migrate_fd_cleanup(FdMigrationState *s)
187 qemu_set_fd_handler2(s->fd, NULL, NULL, NULL, NULL);
189 if (s->file) {
190 dprintf("closing file\n");
191 qemu_fclose(s->file);
194 if (s->fd != -1)
195 close(s->fd);
197 /* Don't resume monitor until we've flushed all of the buffers */
198 if (s->mon_resume)
199 monitor_resume(s->mon_resume);
201 s->fd = -1;
204 void migrate_fd_put_notify(void *opaque)
206 FdMigrationState *s = opaque;
208 qemu_set_fd_handler2(s->fd, NULL, NULL, NULL, NULL);
209 qemu_file_put_notify(s->file);
212 ssize_t migrate_fd_put_buffer(void *opaque, const void *data, size_t size)
214 FdMigrationState *s = opaque;
215 ssize_t ret;
217 do {
218 ret = s->write(s, data, size);
219 } while (ret == -1 && ((s->get_error(s)) == EINTR));
221 if (ret == -1)
222 ret = -(s->get_error(s));
224 if (ret == -EAGAIN)
225 qemu_set_fd_handler2(s->fd, NULL, NULL, migrate_fd_put_notify, s);
227 return ret;
230 void migrate_fd_connect(FdMigrationState *s)
232 int ret;
234 s->file = qemu_fopen_ops_buffered(s,
235 s->bandwidth_limit,
236 migrate_fd_put_buffer,
237 migrate_fd_put_ready,
238 migrate_fd_wait_for_unfreeze,
239 migrate_fd_close);
241 dprintf("beginning savevm\n");
242 ret = qemu_savevm_state_begin(s->file);
243 if (ret < 0) {
244 dprintf("failed, %d\n", ret);
245 migrate_fd_error(s);
246 return;
249 migrate_fd_put_ready(s);
252 void migrate_fd_put_ready(void *opaque)
254 FdMigrationState *s = opaque;
256 if (s->state != MIG_STATE_ACTIVE) {
257 dprintf("put_ready returning because of non-active state\n");
258 return;
261 dprintf("iterate\n");
262 if (qemu_savevm_state_iterate(s->file) == 1) {
263 int state;
264 int old_vm_running = vm_running;
266 dprintf("done iterating\n");
267 vm_stop(0);
269 qemu_aio_flush();
270 bdrv_flush_all();
271 if ((qemu_savevm_state_complete(s->file)) < 0) {
272 if (old_vm_running) {
273 vm_start();
275 state = MIG_STATE_ERROR;
276 } else {
277 state = MIG_STATE_COMPLETED;
279 migrate_fd_cleanup(s);
280 s->state = state;
284 int migrate_fd_get_status(MigrationState *mig_state)
286 FdMigrationState *s = migrate_to_fms(mig_state);
287 return s->state;
290 void migrate_fd_cancel(MigrationState *mig_state)
292 FdMigrationState *s = migrate_to_fms(mig_state);
294 if (s->state != MIG_STATE_ACTIVE)
295 return;
297 dprintf("cancelling migration\n");
299 s->state = MIG_STATE_CANCELLED;
301 migrate_fd_cleanup(s);
304 void migrate_fd_release(MigrationState *mig_state)
306 FdMigrationState *s = migrate_to_fms(mig_state);
308 dprintf("releasing state\n");
310 if (s->state == MIG_STATE_ACTIVE) {
311 s->state = MIG_STATE_CANCELLED;
312 migrate_fd_cleanup(s);
314 free(s);
317 void migrate_fd_wait_for_unfreeze(void *opaque)
319 FdMigrationState *s = opaque;
320 int ret;
322 dprintf("wait for unfreeze\n");
323 if (s->state != MIG_STATE_ACTIVE)
324 return;
326 do {
327 fd_set wfds;
329 FD_ZERO(&wfds);
330 FD_SET(s->fd, &wfds);
332 ret = select(s->fd + 1, NULL, &wfds, NULL, NULL);
333 } while (ret == -1 && (s->get_error(s)) == EINTR);
336 int migrate_fd_close(void *opaque)
338 FdMigrationState *s = opaque;
340 qemu_set_fd_handler2(s->fd, NULL, NULL, NULL, NULL);
341 return s->close(s);