summaryrefslogtreecommitdiffstats
path: root/qemu/include/migration/migration.h
blob: ac2c12c2a518651bb8b654166b377b45ca6ac30f (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
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
/*
 * 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.
 *
 */

#ifndef QEMU_MIGRATION_H
#define QEMU_MIGRATION_H

#include "qapi/qmp/qdict.h"
#include "qemu-common.h"
#include "qemu/thread.h"
#include "qemu/notify.h"
#include "migration/vmstate.h"
#include "qapi-types.h"
#include "exec/cpu-common.h"

#define QEMU_VM_FILE_MAGIC           0x5145564d
#define QEMU_VM_FILE_VERSION_COMPAT  0x00000002
#define QEMU_VM_FILE_VERSION         0x00000003

#define QEMU_VM_EOF                  0x00
#define QEMU_VM_SECTION_START        0x01
#define QEMU_VM_SECTION_PART         0x02
#define QEMU_VM_SECTION_END          0x03
#define QEMU_VM_SECTION_FULL         0x04
#define QEMU_VM_SUBSECTION           0x05
#define QEMU_VM_VMDESCRIPTION        0x06
#define QEMU_VM_CONFIGURATION        0x07
#define QEMU_VM_COMMAND              0x08
#define QEMU_VM_SECTION_FOOTER       0x7e

struct MigrationParams {
    bool blk;
    bool shared;
};

/* Messages sent on the return path from destination to source */
enum mig_rp_message_type {
    MIG_RP_MSG_INVALID = 0,  /* Must be 0 */
    MIG_RP_MSG_SHUT,         /* sibling will not send any more RP messages */
    MIG_RP_MSG_PONG,         /* Response to a PING; data (seq: be32 ) */

    MIG_RP_MSG_REQ_PAGES_ID, /* data (start: be64, len: be32, id: string) */
    MIG_RP_MSG_REQ_PAGES,    /* data (start: be64, len: be32) */

    MIG_RP_MSG_MAX
};

typedef QLIST_HEAD(, LoadStateEntry) LoadStateEntry_Head;

/* The current postcopy state is read/set by postcopy_state_get/set
 * which update it atomically.
 * The state is updated as postcopy messages are received, and
 * in general only one thread should be writing to the state at any one
 * time, initially the main thread and then the listen thread;
 * Corner cases are where either thread finishes early and/or errors.
 * The state is checked as messages are received to ensure that
 * the source is sending us messages in the correct order.
 * The state is also used by the RAM reception code to know if it
 * has to place pages atomically, and the cleanup code at the end of
 * the main thread to know if it has to delay cleanup until the end
 * of postcopy.
 */
typedef enum {
    POSTCOPY_INCOMING_NONE = 0,  /* Initial state - no postcopy */
    POSTCOPY_INCOMING_ADVISE,
    POSTCOPY_INCOMING_DISCARD,
    POSTCOPY_INCOMING_LISTENING,
    POSTCOPY_INCOMING_RUNNING,
    POSTCOPY_INCOMING_END
} PostcopyState;

/* State for the incoming migration */
struct MigrationIncomingState {
    QEMUFile *from_src_file;

    /*
     * Free at the start of the main state load, set as the main thread finishes
     * loading state.
     */
    QemuEvent main_thread_load_event;

    bool           have_fault_thread;
    QemuThread     fault_thread;
    QemuSemaphore  fault_thread_sem;

    bool           have_listen_thread;
    QemuThread     listen_thread;
    QemuSemaphore  listen_thread_sem;

    /* For the kernel to send us notifications */
    int       userfault_fd;
    /* To tell the fault_thread to quit */
    int       userfault_quit_fd;
    QEMUFile *to_src_file;
    QemuMutex rp_mutex;    /* We send replies from multiple threads */
    void     *postcopy_tmp_page;

    QEMUBH *bh;

    int state;
    /* See savevm.c */
    LoadStateEntry_Head loadvm_handlers;
};

MigrationIncomingState *migration_incoming_get_current(void);
MigrationIncomingState *migration_incoming_state_new(QEMUFile *f);
void migration_incoming_state_destroy(void);

/*
 * An outstanding page request, on the source, having been received
 * and queued
 */
struct MigrationSrcPageRequest {
    RAMBlock *rb;
    hwaddr    offset;
    hwaddr    len;

    QSIMPLEQ_ENTRY(MigrationSrcPageRequest) next_req;
};

struct MigrationState
{
    int64_t bandwidth_limit;
    size_t bytes_xfer;
    size_t xfer_limit;
    QemuThread thread;
    QEMUBH *cleanup_bh;
    QEMUFile *to_dst_file;
    int parameters[MIGRATION_PARAMETER__MAX];

    int state;
    MigrationParams params;

    /* State related to return path */
    struct {
        QEMUFile     *from_dst_file;
        QemuThread    rp_thread;
        bool          error;
    } rp_state;

    double mbps;
    int64_t total_time;
    int64_t downtime;
    int64_t expected_downtime;
    int64_t dirty_pages_rate;
    int64_t dirty_bytes_rate;
    bool enabled_capabilities[MIGRATION_CAPABILITY__MAX];
    int64_t xbzrle_cache_size;
    int64_t setup_time;
    int64_t dirty_sync_count;

    /* Flag set once the migration has been asked to enter postcopy */
    bool start_postcopy;
    /* Flag set after postcopy has sent the device state */
    bool postcopy_after_devices;

    /* Flag set once the migration thread is running (and needs joining) */
    bool migration_thread_running;

    /* Queue of outstanding page requests from the destination */
    QemuMutex src_page_req_mutex;
    QSIMPLEQ_HEAD(src_page_requests, MigrationSrcPageRequest) src_page_requests;
    /* The RAMBlock used in the last src_page_request */
    RAMBlock *last_req_rb;
};

void migrate_set_state(int *state, int old_state, int new_state);

void process_incoming_migration(QEMUFile *f);

void qemu_start_incoming_migration(const char *uri, Error **errp);

uint64_t migrate_max_downtime(void);

void exec_start_incoming_migration(const char *host_port, Error **errp);

void exec_start_outgoing_migration(MigrationState *s, const char *host_port, Error **errp);

void tcp_start_incoming_migration(const char *host_port, Error **errp);

void tcp_start_outgoing_migration(MigrationState *s, const char *host_port, Error **errp);

void unix_start_incoming_migration(const char *path, Error **errp);

void unix_start_outgoing_migration(MigrationState *s, const char *path, Error **errp);

void fd_start_incoming_migration(const char *path, Error **errp);

void fd_start_outgoing_migration(MigrationState *s, const char *fdname, Error **errp);

void rdma_start_outgoing_migration(void *opaque, const char *host_port, Error **errp);

void rdma_start_incoming_migration(const char *host_port, Error **errp);

void migrate_fd_error(MigrationState *s);

void migrate_fd_connect(MigrationState *s);

int migrate_fd_close(MigrationState *s);

void add_migration_state_change_notifier(Notifier *notify);
void remove_migration_state_change_notifier(Notifier *notify);
MigrationState *migrate_init(const MigrationParams *params);
bool migration_in_setup(MigrationState *);
bool migration_has_finished(MigrationState *);
bool migration_has_failed(MigrationState *);
/* True if outgoing migration has entered postcopy phase */
bool migration_in_postcopy(MigrationState *);
/* ...and after the device transmission */
bool migration_in_postcopy_after_devices(MigrationState *);
MigrationState *migrate_get_current(void);

void migrate_compress_threads_create(void);
void migrate_compress_threads_join(void);
void migrate_decompress_threads_create(void);
void migrate_decompress_threads_join(void);
uint64_t ram_bytes_remaining(void);
uint64_t ram_bytes_transferred(void);
uint64_t ram_bytes_total(void);
void free_xbzrle_decoded_buf(void);

void acct_update_position(QEMUFile *f, size_t size, bool zero);

uint64_t dup_mig_bytes_transferred(void);
uint64_t dup_mig_pages_transferred(void);
uint64_t skipped_mig_bytes_transferred(void);
uint64_t skipped_mig_pages_transferred(void);
uint64_t norm_mig_bytes_transferred(void);
uint64_t norm_mig_pages_transferred(void);
uint64_t xbzrle_mig_bytes_transferred(void);
uint64_t xbzrle_mig_pages_transferred(void);
uint64_t xbzrle_mig_pages_overflow(void);
uint64_t xbzrle_mig_pages_cache_miss(void);
double xbzrle_mig_cache_miss_rate(void);

void ram_handle_compressed(void *host, uint8_t ch, uint64_t size);
void ram_debug_dump_bitmap(unsigned long *todump, bool expected);
/* For outgoing discard bitmap */
int ram_postcopy_send_discard_bitmap(MigrationState *ms);
/* For incoming postcopy discard */
int ram_discard_range(MigrationIncomingState *mis, const char *block_name,
                      uint64_t start, size_t length);
int ram_postcopy_incoming_init(MigrationIncomingState *mis);

/**
 * @migrate_add_blocker - prevent migration from proceeding
 *
 * @reason - an error to be returned whenever migration is attempted
 */
void migrate_add_blocker(Error *reason);

/**
 * @migrate_del_blocker - remove a blocking error from migration
 *
 * @reason - the error blocking migration
 */
void migrate_del_blocker(Error *reason);

bool migrate_postcopy_ram(void);
bool migrate_zero_blocks(void);

bool migrate_auto_converge(void);

int xbzrle_encode_buffer(uint8_t *old_buf, uint8_t *new_buf, int slen,
                         uint8_t *dst, int dlen);
int xbzrle_decode_buffer(uint8_t *src, int slen, uint8_t *dst, int dlen);

int migrate_use_xbzrle(void);
int64_t migrate_xbzrle_cache_size(void);

int64_t xbzrle_cache_resize(int64_t new_size);

bool migrate_use_compression(void);
int migrate_compress_level(void);
int migrate_compress_threads(void);
int migrate_decompress_threads(void);
bool migrate_use_events(void);

/* Sending on the return path - generic and then for each message type */
void migrate_send_rp_message(MigrationIncomingState *mis,
                             enum mig_rp_message_type message_type,
                             uint16_t len, void *data);
void migrate_send_rp_shut(MigrationIncomingState *mis,
                          uint32_t value);
void migrate_send_rp_pong(MigrationIncomingState *mis,
                          uint32_t value);
void migrate_send_rp_req_pages(MigrationIncomingState *mis, const char* rbname,
                              ram_addr_t start, size_t len);

void ram_control_before_iterate(QEMUFile *f, uint64_t flags);
void ram_control_after_iterate(QEMUFile *f, uint64_t flags);
void ram_control_load_hook(QEMUFile *f, uint64_t flags, void *data);

/* Whenever this is found in the data stream, the flags
 * will be passed to ram_control_load_hook in the incoming-migration
 * side. This lets before_ram_iterate/after_ram_iterate add
 * transport-specific sections to the RAM migration data.
 */
#define RAM_SAVE_FLAG_HOOK     0x80

#define RAM_SAVE_CONTROL_NOT_SUPP -1000
#define RAM_SAVE_CONTROL_DELAYED  -2000

size_t ram_control_save_page(QEMUFile *f, ram_addr_t block_offset,
                             ram_addr_t offset, size_t size,
                             uint64_t *bytes_sent);

void ram_mig_init(void);
void savevm_skip_section_footers(void);
void register_global_state(void);
void global_state_set_optional(void);
void savevm_skip_configuration(void);
int global_state_store(void);
void global_state_store_running(void);

void flush_page_queue(MigrationState *ms);
int ram_save_queue_pages(MigrationState *ms, const char *rbname,
                         ram_addr_t start, ram_addr_t len);

PostcopyState postcopy_state_get(void);
/* Set the state and return the old state */
PostcopyState postcopy_state_set(PostcopyState new_state);
#endif