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     QemuThread     fault_thread;
  90     QemuSemaphore  fault_thread_sem;
  91
  92     /* For the kernel to send us notifications */
  93     int       userfault_fd;
  94     QEMUFile *to_src_file;
  95     QemuMutex rp_mutex;    /* We send replies from multiple threads */
  96
  97     /* See savevm.c */
  98     LoadStateEntry_Head loadvm_handlers;
  99 };
 100
 101 MigrationIncomingState *migration_incoming_get_current(void);
 102 MigrationIncomingState *migration_incoming_state_new(QEMUFile *f);
 103 void migration_incoming_state_destroy(void);
 104
 105 struct MigrationState
 106 {
 107     int64_t bandwidth_limit;
 108     size_t bytes_xfer;
 109     size_t xfer_limit;
 110     QemuThread thread;
 111     QEMUBH *cleanup_bh;
 112     QEMUFile *file;
 113     int parameters[MIGRATION_PARAMETER_MAX];
 114
 115     int state;
 116     MigrationParams params;
 117
 118     /* State related to return path */
 119     struct {
 120         QEMUFile     *from_dst_file;
 121         QemuThread    rp_thread;
 122         bool          error;
 123     } rp_state;
 124
 125     double mbps;
 126     int64_t total_time;
 127     int64_t downtime;
 128     int64_t expected_downtime;
 129     int64_t dirty_pages_rate;
 130     int64_t dirty_bytes_rate;
 131     bool enabled_capabilities[MIGRATION_CAPABILITY_MAX];
 132     int64_t xbzrle_cache_size;
 133     int64_t setup_time;
 134     int64_t dirty_sync_count;
 135
 136     /* Flag set once the migration has been asked to enter postcopy */
 137     bool start_postcopy;
 138 };
 139
 140 void process_incoming_migration(QEMUFile *f);
 141
 142 void qemu_start_incoming_migration(const char *uri, Error **errp);
 143
 144 uint64_t migrate_max_downtime(void);
 145
 146 void exec_start_incoming_migration(const char *host_port, Error **errp);
 147
 148 void exec_start_outgoing_migration(MigrationState *s, const char *host_port, Error **errp);
 149
 150 void tcp_start_incoming_migration(const char *host_port, Error **errp);
 151
 152 void tcp_start_outgoing_migration(MigrationState *s, const char *host_port, Error **errp);
 153
 154 void unix_start_incoming_migration(const char *path, Error **errp);
 155
 156 void unix_start_outgoing_migration(MigrationState *s, const char *path, Error **errp);
 157
 158 void fd_start_incoming_migration(const char *path, Error **errp);
 159
 160 void fd_start_outgoing_migration(MigrationState *s, const char *fdname, Error **errp);
 161
 162 void rdma_start_outgoing_migration(void *opaque, const char *host_port, Error **errp);
 163
 164 void rdma_start_incoming_migration(const char *host_port, Error **errp);
 165
 166 void migrate_fd_error(MigrationState *s);
 167
 168 void migrate_fd_connect(MigrationState *s);
 169
 170 int migrate_fd_close(MigrationState *s);
 171
 172 void add_migration_state_change_notifier(Notifier *notify);
 173 void remove_migration_state_change_notifier(Notifier *notify);
 174 MigrationState *migrate_init(const MigrationParams *params);
 175 bool migration_in_setup(MigrationState *);
 176 bool migration_has_finished(MigrationState *);
 177 bool migration_has_failed(MigrationState *);
 178 /* True if outgoing migration has entered postcopy phase */
 179 bool migration_in_postcopy(MigrationState *);
 180 MigrationState *migrate_get_current(void);
 181
 182 void migrate_compress_threads_create(void);
 183 void migrate_compress_threads_join(void);
 184 void migrate_decompress_threads_create(void);
 185 void migrate_decompress_threads_join(void);
 186 uint64_t ram_bytes_remaining(void);
 187 uint64_t ram_bytes_transferred(void);
 188 uint64_t ram_bytes_total(void);
 189 void free_xbzrle_decoded_buf(void);
 190
 191 void acct_update_position(QEMUFile *f, size_t size, bool zero);
 192
 193 uint64_t dup_mig_bytes_transferred(void);
 194 uint64_t dup_mig_pages_transferred(void);
 195 uint64_t skipped_mig_bytes_transferred(void);
 196 uint64_t skipped_mig_pages_transferred(void);
 197 uint64_t norm_mig_bytes_transferred(void);
 198 uint64_t norm_mig_pages_transferred(void);
 199 uint64_t xbzrle_mig_bytes_transferred(void);
 200 uint64_t xbzrle_mig_pages_transferred(void);
 201 uint64_t xbzrle_mig_pages_overflow(void);
 202 uint64_t xbzrle_mig_pages_cache_miss(void);
 203 double xbzrle_mig_cache_miss_rate(void);
 204
 205 void ram_handle_compressed(void *host, uint8_t ch, uint64_t size);
 206 void ram_debug_dump_bitmap(unsigned long *todump, bool expected);
 207 /* For outgoing discard bitmap */
 208 int ram_postcopy_send_discard_bitmap(MigrationState *ms);
 209 /* For incoming postcopy discard */
 210 int ram_discard_range(MigrationIncomingState *mis, const char *block_name,
 211                       uint64_t start, size_t length);
 212 int ram_postcopy_incoming_init(MigrationIncomingState *mis);
 213
 214 /**
 215  * @migrate_add_blocker - prevent migration from proceeding
 216  *
 217  * @reason - an error to be returned whenever migration is attempted
 218  */
 219 void migrate_add_blocker(Error *reason);
 220
 221 /**
 222  * @migrate_del_blocker - remove a blocking error from migration
 223  *
 224  * @reason - the error blocking migration
 225  */
 226 void migrate_del_blocker(Error *reason);
 227
 228 bool migrate_postcopy_ram(void);
 229 bool migrate_zero_blocks(void);
 230
 231 bool migrate_auto_converge(void);
 232
 233 int xbzrle_encode_buffer(uint8_t *old_buf, uint8_t *new_buf, int slen,
 234                          uint8_t *dst, int dlen);
 235 int xbzrle_decode_buffer(uint8_t *src, int slen, uint8_t *dst, int dlen);
 236
 237 int migrate_use_xbzrle(void);
 238 int64_t migrate_xbzrle_cache_size(void);
 239
 240 int64_t xbzrle_cache_resize(int64_t new_size);
 241
 242 bool migrate_use_compression(void);
 243 int migrate_compress_level(void);
 244 int migrate_compress_threads(void);
 245 int migrate_decompress_threads(void);
 246 bool migrate_use_events(void);
 247
 248 /* Sending on the return path - generic and then for each message type */
 249 void migrate_send_rp_message(MigrationIncomingState *mis,
 250                              enum mig_rp_message_type message_type,
 251                              uint16_t len, void *data);
 252 void migrate_send_rp_shut(MigrationIncomingState *mis,
 253                           uint32_t value);
 254 void migrate_send_rp_pong(MigrationIncomingState *mis,
 255                           uint32_t value);
 256
 257 void ram_control_before_iterate(QEMUFile *f, uint64_t flags);
 258 void ram_control_after_iterate(QEMUFile *f, uint64_t flags);
 259 void ram_control_load_hook(QEMUFile *f, uint64_t flags, void *data);
 260
 261 /* Whenever this is found in the data stream, the flags
 262  * will be passed to ram_control_load_hook in the incoming-migration
 263  * side. This lets before_ram_iterate/after_ram_iterate add
 264  * transport-specific sections to the RAM migration data.
 265  */
 266 #define RAM_SAVE_FLAG_HOOK     0x80
 267
 268 #define RAM_SAVE_CONTROL_NOT_SUPP -1000
 269 #define RAM_SAVE_CONTROL_DELAYED  -2000
 270
 271 size_t ram_control_save_page(QEMUFile *f, ram_addr_t block_offset,
 272                              ram_addr_t offset, size_t size,
 273                              uint64_t *bytes_sent);
 274
 275 void ram_mig_init(void);
 276 void savevm_skip_section_footers(void);
 277 void register_global_state(void);
 278 void global_state_set_optional(void);
 279 void savevm_skip_configuration(void);
 280 int global_state_store(void);
 281 void global_state_store_running(void);
 282
 283 PostcopyState postcopy_state_get(void);
 284 /* Set the state and return the old state */
 285 PostcopyState postcopy_state_set(PostcopyState new_state);
 286 #endif