migrate_start_postcopy: Command to trigger transition to postcopy
[sdk/emulator/qemu.git] / include / migration / migration.h
1 /*
2  * QEMU live migration
3  *
4  * Copyright IBM, Corp. 2008
5  *
6  * Authors:
7  *  Anthony Liguori   <aliguori@us.ibm.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  */
13
14 #ifndef QEMU_MIGRATION_H
15 #define QEMU_MIGRATION_H
16
17 #include "qapi/qmp/qdict.h"
18 #include "qemu-common.h"
19 #include "qemu/thread.h"
20 #include "qemu/notify.h"
21 #include "qapi/error.h"
22 #include "migration/vmstate.h"
23 #include "qapi-types.h"
24 #include "exec/cpu-common.h"
25
26 #define QEMU_VM_FILE_MAGIC           0x5145564d
27 #define QEMU_VM_FILE_VERSION_COMPAT  0x00000002
28 #define QEMU_VM_FILE_VERSION         0x00000003
29
30 #define QEMU_VM_EOF                  0x00
31 #define QEMU_VM_SECTION_START        0x01
32 #define QEMU_VM_SECTION_PART         0x02
33 #define QEMU_VM_SECTION_END          0x03
34 #define QEMU_VM_SECTION_FULL         0x04
35 #define QEMU_VM_SUBSECTION           0x05
36 #define QEMU_VM_VMDESCRIPTION        0x06
37 #define QEMU_VM_CONFIGURATION        0x07
38 #define QEMU_VM_COMMAND              0x08
39 #define QEMU_VM_SECTION_FOOTER       0x7e
40
41 struct MigrationParams {
42     bool blk;
43     bool shared;
44 };
45
46 /* Messages sent on the return path from destination to source */
47 enum mig_rp_message_type {
48     MIG_RP_MSG_INVALID = 0,  /* Must be 0 */
49     MIG_RP_MSG_SHUT,         /* sibling will not send any more RP messages */
50     MIG_RP_MSG_PONG,         /* Response to a PING; data (seq: be32 ) */
51
52     MIG_RP_MSG_MAX
53 };
54
55 typedef QLIST_HEAD(, LoadStateEntry) LoadStateEntry_Head;
56
57 /* The current postcopy state is read/set by postcopy_state_get/set
58  * which update it atomically.
59  * The state is updated as postcopy messages are received, and
60  * in general only one thread should be writing to the state at any one
61  * time, initially the main thread and then the listen thread;
62  * Corner cases are where either thread finishes early and/or errors.
63  * The state is checked as messages are received to ensure that
64  * the source is sending us messages in the correct order.
65  * The state is also used by the RAM reception code to know if it
66  * has to place pages atomically, and the cleanup code at the end of
67  * the main thread to know if it has to delay cleanup until the end
68  * of postcopy.
69  */
70 typedef enum {
71     POSTCOPY_INCOMING_NONE = 0,  /* Initial state - no postcopy */
72     POSTCOPY_INCOMING_ADVISE,
73     POSTCOPY_INCOMING_DISCARD,
74     POSTCOPY_INCOMING_LISTENING,
75     POSTCOPY_INCOMING_RUNNING,
76     POSTCOPY_INCOMING_END
77 } PostcopyState;
78
79 /* State for the incoming migration */
80 struct MigrationIncomingState {
81     QEMUFile *from_src_file;
82
83     /*
84      * Free at the start of the main state load, set as the main thread finishes
85      * loading state.
86      */
87     QemuEvent main_thread_load_event;
88
89     QEMUFile *to_src_file;
90     QemuMutex rp_mutex;    /* We send replies from multiple threads */
91
92     /* See savevm.c */
93     LoadStateEntry_Head loadvm_handlers;
94 };
95
96 MigrationIncomingState *migration_incoming_get_current(void);
97 MigrationIncomingState *migration_incoming_state_new(QEMUFile *f);
98 void migration_incoming_state_destroy(void);
99
100 struct MigrationState
101 {
102     int64_t bandwidth_limit;
103     size_t bytes_xfer;
104     size_t xfer_limit;
105     QemuThread thread;
106     QEMUBH *cleanup_bh;
107     QEMUFile *file;
108     int parameters[MIGRATION_PARAMETER_MAX];
109
110     int state;
111     MigrationParams params;
112
113     /* State related to return path */
114     struct {
115         QEMUFile     *from_dst_file;
116         QemuThread    rp_thread;
117         bool          error;
118     } rp_state;
119
120     double mbps;
121     int64_t total_time;
122     int64_t downtime;
123     int64_t expected_downtime;
124     int64_t dirty_pages_rate;
125     int64_t dirty_bytes_rate;
126     bool enabled_capabilities[MIGRATION_CAPABILITY_MAX];
127     int64_t xbzrle_cache_size;
128     int64_t setup_time;
129     int64_t dirty_sync_count;
130
131     /* Flag set once the migration has been asked to enter postcopy */
132     bool start_postcopy;
133 };
134
135 void process_incoming_migration(QEMUFile *f);
136
137 void qemu_start_incoming_migration(const char *uri, Error **errp);
138
139 uint64_t migrate_max_downtime(void);
140
141 void exec_start_incoming_migration(const char *host_port, Error **errp);
142
143 void exec_start_outgoing_migration(MigrationState *s, const char *host_port, Error **errp);
144
145 void tcp_start_incoming_migration(const char *host_port, Error **errp);
146
147 void tcp_start_outgoing_migration(MigrationState *s, const char *host_port, Error **errp);
148
149 void unix_start_incoming_migration(const char *path, Error **errp);
150
151 void unix_start_outgoing_migration(MigrationState *s, const char *path, Error **errp);
152
153 void fd_start_incoming_migration(const char *path, Error **errp);
154
155 void fd_start_outgoing_migration(MigrationState *s, const char *fdname, Error **errp);
156
157 void rdma_start_outgoing_migration(void *opaque, const char *host_port, Error **errp);
158
159 void rdma_start_incoming_migration(const char *host_port, Error **errp);
160
161 void migrate_fd_error(MigrationState *s);
162
163 void migrate_fd_connect(MigrationState *s);
164
165 int migrate_fd_close(MigrationState *s);
166
167 void add_migration_state_change_notifier(Notifier *notify);
168 void remove_migration_state_change_notifier(Notifier *notify);
169 MigrationState *migrate_init(const MigrationParams *params);
170 bool migration_in_setup(MigrationState *);
171 bool migration_has_finished(MigrationState *);
172 bool migration_has_failed(MigrationState *);
173 MigrationState *migrate_get_current(void);
174
175 void migrate_compress_threads_create(void);
176 void migrate_compress_threads_join(void);
177 void migrate_decompress_threads_create(void);
178 void migrate_decompress_threads_join(void);
179 uint64_t ram_bytes_remaining(void);
180 uint64_t ram_bytes_transferred(void);
181 uint64_t ram_bytes_total(void);
182 void free_xbzrle_decoded_buf(void);
183
184 void acct_update_position(QEMUFile *f, size_t size, bool zero);
185
186 uint64_t dup_mig_bytes_transferred(void);
187 uint64_t dup_mig_pages_transferred(void);
188 uint64_t skipped_mig_bytes_transferred(void);
189 uint64_t skipped_mig_pages_transferred(void);
190 uint64_t norm_mig_bytes_transferred(void);
191 uint64_t norm_mig_pages_transferred(void);
192 uint64_t xbzrle_mig_bytes_transferred(void);
193 uint64_t xbzrle_mig_pages_transferred(void);
194 uint64_t xbzrle_mig_pages_overflow(void);
195 uint64_t xbzrle_mig_pages_cache_miss(void);
196 double xbzrle_mig_cache_miss_rate(void);
197
198 void ram_handle_compressed(void *host, uint8_t ch, uint64_t size);
199 void ram_debug_dump_bitmap(unsigned long *todump, bool expected);
200
201 /**
202  * @migrate_add_blocker - prevent migration from proceeding
203  *
204  * @reason - an error to be returned whenever migration is attempted
205  */
206 void migrate_add_blocker(Error *reason);
207
208 /**
209  * @migrate_del_blocker - remove a blocking error from migration
210  *
211  * @reason - the error blocking migration
212  */
213 void migrate_del_blocker(Error *reason);
214
215 bool migrate_postcopy_ram(void);
216 bool migrate_zero_blocks(void);
217
218 bool migrate_auto_converge(void);
219
220 int xbzrle_encode_buffer(uint8_t *old_buf, uint8_t *new_buf, int slen,
221                          uint8_t *dst, int dlen);
222 int xbzrle_decode_buffer(uint8_t *src, int slen, uint8_t *dst, int dlen);
223
224 int migrate_use_xbzrle(void);
225 int64_t migrate_xbzrle_cache_size(void);
226
227 int64_t xbzrle_cache_resize(int64_t new_size);
228
229 bool migrate_use_compression(void);
230 int migrate_compress_level(void);
231 int migrate_compress_threads(void);
232 int migrate_decompress_threads(void);
233 bool migrate_use_events(void);
234
235 /* Sending on the return path - generic and then for each message type */
236 void migrate_send_rp_message(MigrationIncomingState *mis,
237                              enum mig_rp_message_type message_type,
238                              uint16_t len, void *data);
239 void migrate_send_rp_shut(MigrationIncomingState *mis,
240                           uint32_t value);
241 void migrate_send_rp_pong(MigrationIncomingState *mis,
242                           uint32_t value);
243
244 void ram_control_before_iterate(QEMUFile *f, uint64_t flags);
245 void ram_control_after_iterate(QEMUFile *f, uint64_t flags);
246 void ram_control_load_hook(QEMUFile *f, uint64_t flags, void *data);
247
248 /* Whenever this is found in the data stream, the flags
249  * will be passed to ram_control_load_hook in the incoming-migration
250  * side. This lets before_ram_iterate/after_ram_iterate add
251  * transport-specific sections to the RAM migration data.
252  */
253 #define RAM_SAVE_FLAG_HOOK     0x80
254
255 #define RAM_SAVE_CONTROL_NOT_SUPP -1000
256 #define RAM_SAVE_CONTROL_DELAYED  -2000
257
258 size_t ram_control_save_page(QEMUFile *f, ram_addr_t block_offset,
259                              ram_addr_t offset, size_t size,
260                              uint64_t *bytes_sent);
261
262 void ram_mig_init(void);
263 void savevm_skip_section_footers(void);
264 void register_global_state(void);
265 void global_state_set_optional(void);
266 void savevm_skip_configuration(void);
267 int global_state_store(void);
268 void global_state_store_running(void);
269
270 PostcopyState postcopy_state_get(void);
271 /* Set the state and return the old state */
272 PostcopyState postcopy_state_set(PostcopyState new_state);
273 #endif