 decdc76772
			
		
	
	
		decdc76772
		
	
	
	
	
		
			
			If we receive a file descriptor that points to a regular file, there's nothing stopping us from doing multifd migration with mapped-ram to that file. Enable the fd: URI to work with multifd + mapped-ram. Note that the fds passed into multifd are duplicated because we want to avoid cross-thread effects when doing cleanup (i.e. close(fd)). The original fd doesn't need to be duplicated because monitor_get_fd() transfers ownership to the caller. Signed-off-by: Fabiano Rosas <farosas@suse.de> Reviewed-by: Peter Xu <peterx@redhat.com> Link: https://lore.kernel.org/r/20240229153017.2221-23-farosas@suse.de Signed-off-by: Peter Xu <peterx@redhat.com>
		
			
				
	
	
		
			3836 lines
		
	
	
		
			114 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			3836 lines
		
	
	
		
			114 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
 | |
|  * 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.
 | |
|  *
 | |
|  * Contributions after 2012-01-13 are licensed under the terms of the
 | |
|  * GNU GPL, version 2 or (at your option) any later version.
 | |
|  */
 | |
| 
 | |
| #include "qemu/osdep.h"
 | |
| #include "qemu/cutils.h"
 | |
| #include "qemu/error-report.h"
 | |
| #include "qemu/main-loop.h"
 | |
| #include "migration/blocker.h"
 | |
| #include "exec.h"
 | |
| #include "fd.h"
 | |
| #include "file.h"
 | |
| #include "socket.h"
 | |
| #include "sysemu/runstate.h"
 | |
| #include "sysemu/sysemu.h"
 | |
| #include "sysemu/cpu-throttle.h"
 | |
| #include "rdma.h"
 | |
| #include "ram.h"
 | |
| #include "ram-compress.h"
 | |
| #include "migration/global_state.h"
 | |
| #include "migration/misc.h"
 | |
| #include "migration.h"
 | |
| #include "migration-stats.h"
 | |
| #include "savevm.h"
 | |
| #include "qemu-file.h"
 | |
| #include "channel.h"
 | |
| #include "migration/vmstate.h"
 | |
| #include "block/block.h"
 | |
| #include "qapi/error.h"
 | |
| #include "qapi/clone-visitor.h"
 | |
| #include "qapi/qapi-visit-migration.h"
 | |
| #include "qapi/qapi-visit-sockets.h"
 | |
| #include "qapi/qapi-commands-migration.h"
 | |
| #include "qapi/qapi-events-migration.h"
 | |
| #include "qapi/qmp/qerror.h"
 | |
| #include "qapi/qmp/qnull.h"
 | |
| #include "qemu/rcu.h"
 | |
| #include "block.h"
 | |
| #include "postcopy-ram.h"
 | |
| #include "qemu/thread.h"
 | |
| #include "trace.h"
 | |
| #include "exec/target_page.h"
 | |
| #include "io/channel-buffer.h"
 | |
| #include "io/channel-tls.h"
 | |
| #include "migration/colo.h"
 | |
| #include "hw/boards.h"
 | |
| #include "monitor/monitor.h"
 | |
| #include "net/announce.h"
 | |
| #include "qemu/queue.h"
 | |
| #include "multifd.h"
 | |
| #include "threadinfo.h"
 | |
| #include "qemu/yank.h"
 | |
| #include "sysemu/cpus.h"
 | |
| #include "yank_functions.h"
 | |
| #include "sysemu/qtest.h"
 | |
| #include "options.h"
 | |
| #include "sysemu/dirtylimit.h"
 | |
| #include "qemu/sockets.h"
 | |
| #include "sysemu/kvm.h"
 | |
| 
 | |
| #define NOTIFIER_ELEM_INIT(array, elem)    \
 | |
|     [elem] = NOTIFIER_WITH_RETURN_LIST_INITIALIZER((array)[elem])
 | |
| 
 | |
| static NotifierWithReturnList migration_state_notifiers[] = {
 | |
|     NOTIFIER_ELEM_INIT(migration_state_notifiers, MIG_MODE_NORMAL),
 | |
|     NOTIFIER_ELEM_INIT(migration_state_notifiers, MIG_MODE_CPR_REBOOT),
 | |
| };
 | |
| 
 | |
| /* 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_RECV_BITMAP,  /* send recved_bitmap back to source */
 | |
|     MIG_RP_MSG_RESUME_ACK,   /* tell source that we are ready to resume */
 | |
|     MIG_RP_MSG_SWITCHOVER_ACK, /* Tell source it's OK to do switchover */
 | |
| 
 | |
|     MIG_RP_MSG_MAX
 | |
| };
 | |
| 
 | |
| /* When we add fault tolerance, we could have several
 | |
|    migrations at once.  For now we don't need to add
 | |
|    dynamic creation of migration */
 | |
| 
 | |
| static MigrationState *current_migration;
 | |
| static MigrationIncomingState *current_incoming;
 | |
| 
 | |
| static GSList *migration_blockers[MIG_MODE__MAX];
 | |
| 
 | |
| static bool migration_object_check(MigrationState *ms, Error **errp);
 | |
| static int migration_maybe_pause(MigrationState *s,
 | |
|                                  int *current_active_state,
 | |
|                                  int new_state);
 | |
| static void migrate_fd_cancel(MigrationState *s);
 | |
| static bool close_return_path_on_source(MigrationState *s);
 | |
| static void migration_completion_end(MigrationState *s);
 | |
| 
 | |
| static void migration_downtime_start(MigrationState *s)
 | |
| {
 | |
|     trace_vmstate_downtime_checkpoint("src-downtime-start");
 | |
|     s->downtime_start = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
 | |
| }
 | |
| 
 | |
| static void migration_downtime_end(MigrationState *s)
 | |
| {
 | |
|     int64_t now = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
 | |
| 
 | |
|     /*
 | |
|      * If downtime already set, should mean that postcopy already set it,
 | |
|      * then that should be the real downtime already.
 | |
|      */
 | |
|     if (!s->downtime) {
 | |
|         s->downtime = now - s->downtime_start;
 | |
|     }
 | |
| 
 | |
|     trace_vmstate_downtime_checkpoint("src-downtime-end");
 | |
| }
 | |
| 
 | |
| static bool migration_needs_multiple_sockets(void)
 | |
| {
 | |
|     return migrate_multifd() || migrate_postcopy_preempt();
 | |
| }
 | |
| 
 | |
| static bool transport_supports_multi_channels(MigrationAddress *addr)
 | |
| {
 | |
|     if (addr->transport == MIGRATION_ADDRESS_TYPE_SOCKET) {
 | |
|         SocketAddress *saddr = &addr->u.socket;
 | |
| 
 | |
|         if (saddr->type == SOCKET_ADDRESS_TYPE_FD) {
 | |
|             return migrate_mapped_ram();
 | |
|         }
 | |
| 
 | |
|         return (saddr->type == SOCKET_ADDRESS_TYPE_INET ||
 | |
|                 saddr->type == SOCKET_ADDRESS_TYPE_UNIX ||
 | |
|                 saddr->type == SOCKET_ADDRESS_TYPE_VSOCK);
 | |
|     } else if (addr->transport == MIGRATION_ADDRESS_TYPE_FILE) {
 | |
|         return migrate_mapped_ram();
 | |
|     } else {
 | |
|         return false;
 | |
|     }
 | |
| }
 | |
| 
 | |
| static bool migration_needs_seekable_channel(void)
 | |
| {
 | |
|     return migrate_mapped_ram();
 | |
| }
 | |
| 
 | |
| static bool transport_supports_seeking(MigrationAddress *addr)
 | |
| {
 | |
|     if (addr->transport == MIGRATION_ADDRESS_TYPE_FILE) {
 | |
|         return true;
 | |
|     }
 | |
| 
 | |
|     /*
 | |
|      * At this point, the user might not yet have passed the file
 | |
|      * descriptor to QEMU, so we cannot know for sure whether it
 | |
|      * refers to a plain file or a socket. Let it through anyway.
 | |
|      */
 | |
|     if (addr->transport == MIGRATION_ADDRESS_TYPE_SOCKET) {
 | |
|         return addr->u.socket.type == SOCKET_ADDRESS_TYPE_FD;
 | |
|     }
 | |
| 
 | |
|     return false;
 | |
| }
 | |
| 
 | |
| static bool
 | |
| migration_channels_and_transport_compatible(MigrationAddress *addr,
 | |
|                                             Error **errp)
 | |
| {
 | |
|     if (migration_needs_seekable_channel() &&
 | |
|         !transport_supports_seeking(addr)) {
 | |
|         error_setg(errp, "Migration requires seekable transport (e.g. file)");
 | |
|         return false;
 | |
|     }
 | |
| 
 | |
|     if (migration_needs_multiple_sockets() &&
 | |
|         !transport_supports_multi_channels(addr)) {
 | |
|         error_setg(errp, "Migration requires multi-channel URIs (e.g. tcp)");
 | |
|         return false;
 | |
|     }
 | |
| 
 | |
|     return true;
 | |
| }
 | |
| 
 | |
| static gint page_request_addr_cmp(gconstpointer ap, gconstpointer bp)
 | |
| {
 | |
|     uintptr_t a = (uintptr_t) ap, b = (uintptr_t) bp;
 | |
| 
 | |
|     return (a > b) - (a < b);
 | |
| }
 | |
| 
 | |
| static int migration_stop_vm(MigrationState *s, RunState state)
 | |
| {
 | |
|     int ret;
 | |
| 
 | |
|     migration_downtime_start(s);
 | |
| 
 | |
|     s->vm_old_state = runstate_get();
 | |
|     global_state_store();
 | |
| 
 | |
|     ret = vm_stop_force_state(state);
 | |
| 
 | |
|     trace_vmstate_downtime_checkpoint("src-vm-stopped");
 | |
|     trace_migration_completion_vm_stop(ret);
 | |
| 
 | |
|     return ret;
 | |
| }
 | |
| 
 | |
| void migration_object_init(void)
 | |
| {
 | |
|     /* This can only be called once. */
 | |
|     assert(!current_migration);
 | |
|     current_migration = MIGRATION_OBJ(object_new(TYPE_MIGRATION));
 | |
| 
 | |
|     /*
 | |
|      * Init the migrate incoming object as well no matter whether
 | |
|      * we'll use it or not.
 | |
|      */
 | |
|     assert(!current_incoming);
 | |
|     current_incoming = g_new0(MigrationIncomingState, 1);
 | |
|     current_incoming->state = MIGRATION_STATUS_NONE;
 | |
|     current_incoming->postcopy_remote_fds =
 | |
|         g_array_new(FALSE, TRUE, sizeof(struct PostCopyFD));
 | |
|     qemu_mutex_init(¤t_incoming->rp_mutex);
 | |
|     qemu_mutex_init(¤t_incoming->postcopy_prio_thread_mutex);
 | |
|     qemu_event_init(¤t_incoming->main_thread_load_event, false);
 | |
|     qemu_sem_init(¤t_incoming->postcopy_pause_sem_dst, 0);
 | |
|     qemu_sem_init(¤t_incoming->postcopy_pause_sem_fault, 0);
 | |
|     qemu_sem_init(¤t_incoming->postcopy_pause_sem_fast_load, 0);
 | |
|     qemu_sem_init(¤t_incoming->postcopy_qemufile_dst_done, 0);
 | |
| 
 | |
|     qemu_mutex_init(¤t_incoming->page_request_mutex);
 | |
|     qemu_cond_init(¤t_incoming->page_request_cond);
 | |
|     current_incoming->page_requested = g_tree_new(page_request_addr_cmp);
 | |
| 
 | |
|     migration_object_check(current_migration, &error_fatal);
 | |
| 
 | |
|     blk_mig_init();
 | |
|     ram_mig_init();
 | |
|     dirty_bitmap_mig_init();
 | |
| }
 | |
| 
 | |
| typedef struct {
 | |
|     QEMUBH *bh;
 | |
|     QEMUBHFunc *cb;
 | |
|     void *opaque;
 | |
| } MigrationBH;
 | |
| 
 | |
| static void migration_bh_dispatch_bh(void *opaque)
 | |
| {
 | |
|     MigrationState *s = migrate_get_current();
 | |
|     MigrationBH *migbh = opaque;
 | |
| 
 | |
|     /* cleanup this BH */
 | |
|     qemu_bh_delete(migbh->bh);
 | |
|     migbh->bh = NULL;
 | |
| 
 | |
|     /* dispatch the other one */
 | |
|     migbh->cb(migbh->opaque);
 | |
|     object_unref(OBJECT(s));
 | |
| 
 | |
|     g_free(migbh);
 | |
| }
 | |
| 
 | |
| void migration_bh_schedule(QEMUBHFunc *cb, void *opaque)
 | |
| {
 | |
|     MigrationState *s = migrate_get_current();
 | |
|     MigrationBH *migbh = g_new0(MigrationBH, 1);
 | |
|     QEMUBH *bh = qemu_bh_new(migration_bh_dispatch_bh, migbh);
 | |
| 
 | |
|     /* Store these to dispatch when the BH runs */
 | |
|     migbh->bh = bh;
 | |
|     migbh->cb = cb;
 | |
|     migbh->opaque = opaque;
 | |
| 
 | |
|     /*
 | |
|      * Ref the state for bh, because it may be called when
 | |
|      * there're already no other refs
 | |
|      */
 | |
|     object_ref(OBJECT(s));
 | |
|     qemu_bh_schedule(bh);
 | |
| }
 | |
| 
 | |
| void migration_cancel(const Error *error)
 | |
| {
 | |
|     if (error) {
 | |
|         migrate_set_error(current_migration, error);
 | |
|     }
 | |
|     if (migrate_dirty_limit()) {
 | |
|         qmp_cancel_vcpu_dirty_limit(false, -1, NULL);
 | |
|     }
 | |
|     migrate_fd_cancel(current_migration);
 | |
| }
 | |
| 
 | |
| void migration_shutdown(void)
 | |
| {
 | |
|     /*
 | |
|      * When the QEMU main thread exit, the COLO thread
 | |
|      * may wait a semaphore. So, we should wakeup the
 | |
|      * COLO thread before migration shutdown.
 | |
|      */
 | |
|     colo_shutdown();
 | |
|     /*
 | |
|      * Cancel the current migration - that will (eventually)
 | |
|      * stop the migration using this structure
 | |
|      */
 | |
|     migration_cancel(NULL);
 | |
|     object_unref(OBJECT(current_migration));
 | |
| 
 | |
|     /*
 | |
|      * Cancel outgoing migration of dirty bitmaps. It should
 | |
|      * at least unref used block nodes.
 | |
|      */
 | |
|     dirty_bitmap_mig_cancel_outgoing();
 | |
| 
 | |
|     /*
 | |
|      * Cancel incoming migration of dirty bitmaps. Dirty bitmaps
 | |
|      * are non-critical data, and their loss never considered as
 | |
|      * something serious.
 | |
|      */
 | |
|     dirty_bitmap_mig_cancel_incoming();
 | |
| }
 | |
| 
 | |
| /* For outgoing */
 | |
| MigrationState *migrate_get_current(void)
 | |
| {
 | |
|     /* This can only be called after the object created. */
 | |
|     assert(current_migration);
 | |
|     return current_migration;
 | |
| }
 | |
| 
 | |
| MigrationIncomingState *migration_incoming_get_current(void)
 | |
| {
 | |
|     assert(current_incoming);
 | |
|     return current_incoming;
 | |
| }
 | |
| 
 | |
| void migration_incoming_transport_cleanup(MigrationIncomingState *mis)
 | |
| {
 | |
|     if (mis->socket_address_list) {
 | |
|         qapi_free_SocketAddressList(mis->socket_address_list);
 | |
|         mis->socket_address_list = NULL;
 | |
|     }
 | |
| 
 | |
|     if (mis->transport_cleanup) {
 | |
|         mis->transport_cleanup(mis->transport_data);
 | |
|         mis->transport_data = mis->transport_cleanup = NULL;
 | |
|     }
 | |
| }
 | |
| 
 | |
| void migration_incoming_state_destroy(void)
 | |
| {
 | |
|     struct MigrationIncomingState *mis = migration_incoming_get_current();
 | |
| 
 | |
|     multifd_recv_cleanup();
 | |
|     compress_threads_load_cleanup();
 | |
| 
 | |
|     if (mis->to_src_file) {
 | |
|         /* Tell source that we are done */
 | |
|         migrate_send_rp_shut(mis, qemu_file_get_error(mis->from_src_file) != 0);
 | |
|         qemu_fclose(mis->to_src_file);
 | |
|         mis->to_src_file = NULL;
 | |
|     }
 | |
| 
 | |
|     if (mis->from_src_file) {
 | |
|         migration_ioc_unregister_yank_from_file(mis->from_src_file);
 | |
|         qemu_fclose(mis->from_src_file);
 | |
|         mis->from_src_file = NULL;
 | |
|     }
 | |
|     if (mis->postcopy_remote_fds) {
 | |
|         g_array_free(mis->postcopy_remote_fds, TRUE);
 | |
|         mis->postcopy_remote_fds = NULL;
 | |
|     }
 | |
| 
 | |
|     migration_incoming_transport_cleanup(mis);
 | |
|     qemu_event_reset(&mis->main_thread_load_event);
 | |
| 
 | |
|     if (mis->page_requested) {
 | |
|         g_tree_destroy(mis->page_requested);
 | |
|         mis->page_requested = NULL;
 | |
|     }
 | |
| 
 | |
|     if (mis->postcopy_qemufile_dst) {
 | |
|         migration_ioc_unregister_yank_from_file(mis->postcopy_qemufile_dst);
 | |
|         qemu_fclose(mis->postcopy_qemufile_dst);
 | |
|         mis->postcopy_qemufile_dst = NULL;
 | |
|     }
 | |
| 
 | |
|     yank_unregister_instance(MIGRATION_YANK_INSTANCE);
 | |
| }
 | |
| 
 | |
| static void migrate_generate_event(int new_state)
 | |
| {
 | |
|     if (migrate_events()) {
 | |
|         qapi_event_send_migration(new_state);
 | |
|     }
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Send a message on the return channel back to the source
 | |
|  * of the migration.
 | |
|  */
 | |
| static int migrate_send_rp_message(MigrationIncomingState *mis,
 | |
|                                    enum mig_rp_message_type message_type,
 | |
|                                    uint16_t len, void *data)
 | |
| {
 | |
|     int ret = 0;
 | |
| 
 | |
|     trace_migrate_send_rp_message((int)message_type, len);
 | |
|     QEMU_LOCK_GUARD(&mis->rp_mutex);
 | |
| 
 | |
|     /*
 | |
|      * It's possible that the file handle got lost due to network
 | |
|      * failures.
 | |
|      */
 | |
|     if (!mis->to_src_file) {
 | |
|         ret = -EIO;
 | |
|         return ret;
 | |
|     }
 | |
| 
 | |
|     qemu_put_be16(mis->to_src_file, (unsigned int)message_type);
 | |
|     qemu_put_be16(mis->to_src_file, len);
 | |
|     qemu_put_buffer(mis->to_src_file, data, len);
 | |
|     return qemu_fflush(mis->to_src_file);
 | |
| }
 | |
| 
 | |
| /* Request one page from the source VM at the given start address.
 | |
|  *   rb: the RAMBlock to request the page in
 | |
|  *   Start: Address offset within the RB
 | |
|  *   Len: Length in bytes required - must be a multiple of pagesize
 | |
|  */
 | |
| int migrate_send_rp_message_req_pages(MigrationIncomingState *mis,
 | |
|                                       RAMBlock *rb, ram_addr_t start)
 | |
| {
 | |
|     uint8_t bufc[12 + 1 + 255]; /* start (8), len (4), rbname up to 256 */
 | |
|     size_t msglen = 12; /* start + len */
 | |
|     size_t len = qemu_ram_pagesize(rb);
 | |
|     enum mig_rp_message_type msg_type;
 | |
|     const char *rbname;
 | |
|     int rbname_len;
 | |
| 
 | |
|     *(uint64_t *)bufc = cpu_to_be64((uint64_t)start);
 | |
|     *(uint32_t *)(bufc + 8) = cpu_to_be32((uint32_t)len);
 | |
| 
 | |
|     /*
 | |
|      * We maintain the last ramblock that we requested for page.  Note that we
 | |
|      * don't need locking because this function will only be called within the
 | |
|      * postcopy ram fault thread.
 | |
|      */
 | |
|     if (rb != mis->last_rb) {
 | |
|         mis->last_rb = rb;
 | |
| 
 | |
|         rbname = qemu_ram_get_idstr(rb);
 | |
|         rbname_len = strlen(rbname);
 | |
| 
 | |
|         assert(rbname_len < 256);
 | |
| 
 | |
|         bufc[msglen++] = rbname_len;
 | |
|         memcpy(bufc + msglen, rbname, rbname_len);
 | |
|         msglen += rbname_len;
 | |
|         msg_type = MIG_RP_MSG_REQ_PAGES_ID;
 | |
|     } else {
 | |
|         msg_type = MIG_RP_MSG_REQ_PAGES;
 | |
|     }
 | |
| 
 | |
|     return migrate_send_rp_message(mis, msg_type, msglen, bufc);
 | |
| }
 | |
| 
 | |
| int migrate_send_rp_req_pages(MigrationIncomingState *mis,
 | |
|                               RAMBlock *rb, ram_addr_t start, uint64_t haddr)
 | |
| {
 | |
|     void *aligned = (void *)(uintptr_t)ROUND_DOWN(haddr, qemu_ram_pagesize(rb));
 | |
|     bool received = false;
 | |
| 
 | |
|     WITH_QEMU_LOCK_GUARD(&mis->page_request_mutex) {
 | |
|         received = ramblock_recv_bitmap_test_byte_offset(rb, start);
 | |
|         if (!received && !g_tree_lookup(mis->page_requested, aligned)) {
 | |
|             /*
 | |
|              * The page has not been received, and it's not yet in the page
 | |
|              * request list.  Queue it.  Set the value of element to 1, so that
 | |
|              * things like g_tree_lookup() will return TRUE (1) when found.
 | |
|              */
 | |
|             g_tree_insert(mis->page_requested, aligned, (gpointer)1);
 | |
|             qatomic_inc(&mis->page_requested_count);
 | |
|             trace_postcopy_page_req_add(aligned, mis->page_requested_count);
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     /*
 | |
|      * If the page is there, skip sending the message.  We don't even need the
 | |
|      * lock because as long as the page arrived, it'll be there forever.
 | |
|      */
 | |
|     if (received) {
 | |
|         return 0;
 | |
|     }
 | |
| 
 | |
|     return migrate_send_rp_message_req_pages(mis, rb, start);
 | |
| }
 | |
| 
 | |
| static bool migration_colo_enabled;
 | |
| bool migration_incoming_colo_enabled(void)
 | |
| {
 | |
|     return migration_colo_enabled;
 | |
| }
 | |
| 
 | |
| void migration_incoming_disable_colo(void)
 | |
| {
 | |
|     ram_block_discard_disable(false);
 | |
|     migration_colo_enabled = false;
 | |
| }
 | |
| 
 | |
| int migration_incoming_enable_colo(void)
 | |
| {
 | |
| #ifndef CONFIG_REPLICATION
 | |
|     error_report("ENABLE_COLO command come in migration stream, but COLO "
 | |
|                  "module is not built in");
 | |
|     return -ENOTSUP;
 | |
| #endif
 | |
| 
 | |
|     if (!migrate_colo()) {
 | |
|         error_report("ENABLE_COLO command come in migration stream, but c-colo "
 | |
|                      "capability is not set");
 | |
|         return -EINVAL;
 | |
|     }
 | |
| 
 | |
|     if (ram_block_discard_disable(true)) {
 | |
|         error_report("COLO: cannot disable RAM discard");
 | |
|         return -EBUSY;
 | |
|     }
 | |
|     migration_colo_enabled = true;
 | |
|     return 0;
 | |
| }
 | |
| 
 | |
| void migrate_add_address(SocketAddress *address)
 | |
| {
 | |
|     MigrationIncomingState *mis = migration_incoming_get_current();
 | |
| 
 | |
|     QAPI_LIST_PREPEND(mis->socket_address_list,
 | |
|                       QAPI_CLONE(SocketAddress, address));
 | |
| }
 | |
| 
 | |
| bool migrate_uri_parse(const char *uri, MigrationChannel **channel,
 | |
|                        Error **errp)
 | |
| {
 | |
|     g_autoptr(MigrationChannel) val = g_new0(MigrationChannel, 1);
 | |
|     g_autoptr(MigrationAddress) addr = g_new0(MigrationAddress, 1);
 | |
|     InetSocketAddress *isock = &addr->u.rdma;
 | |
|     strList **tail = &addr->u.exec.args;
 | |
| 
 | |
|     if (strstart(uri, "exec:", NULL)) {
 | |
|         addr->transport = MIGRATION_ADDRESS_TYPE_EXEC;
 | |
| #ifdef WIN32
 | |
|         QAPI_LIST_APPEND(tail, g_strdup(exec_get_cmd_path()));
 | |
|         QAPI_LIST_APPEND(tail, g_strdup("/c"));
 | |
| #else
 | |
|         QAPI_LIST_APPEND(tail, g_strdup("/bin/sh"));
 | |
|         QAPI_LIST_APPEND(tail, g_strdup("-c"));
 | |
| #endif
 | |
|         QAPI_LIST_APPEND(tail, g_strdup(uri + strlen("exec:")));
 | |
|     } else if (strstart(uri, "rdma:", NULL)) {
 | |
|         if (inet_parse(isock, uri + strlen("rdma:"), errp)) {
 | |
|             qapi_free_InetSocketAddress(isock);
 | |
|             return false;
 | |
|         }
 | |
|         addr->transport = MIGRATION_ADDRESS_TYPE_RDMA;
 | |
|     } else if (strstart(uri, "tcp:", NULL) ||
 | |
|                 strstart(uri, "unix:", NULL) ||
 | |
|                 strstart(uri, "vsock:", NULL) ||
 | |
|                 strstart(uri, "fd:", NULL)) {
 | |
|         addr->transport = MIGRATION_ADDRESS_TYPE_SOCKET;
 | |
|         SocketAddress *saddr = socket_parse(uri, errp);
 | |
|         if (!saddr) {
 | |
|             return false;
 | |
|         }
 | |
|         addr->u.socket.type = saddr->type;
 | |
|         addr->u.socket.u = saddr->u;
 | |
|         /* Don't free the objects inside; their ownership moved to "addr" */
 | |
|         g_free(saddr);
 | |
|     } else if (strstart(uri, "file:", NULL)) {
 | |
|         addr->transport = MIGRATION_ADDRESS_TYPE_FILE;
 | |
|         addr->u.file.filename = g_strdup(uri + strlen("file:"));
 | |
|         if (file_parse_offset(addr->u.file.filename, &addr->u.file.offset,
 | |
|                               errp)) {
 | |
|             return false;
 | |
|         }
 | |
|     } else {
 | |
|         error_setg(errp, "unknown migration protocol: %s", uri);
 | |
|         return false;
 | |
|     }
 | |
| 
 | |
|     val->channel_type = MIGRATION_CHANNEL_TYPE_MAIN;
 | |
|     val->addr = g_steal_pointer(&addr);
 | |
|     *channel = g_steal_pointer(&val);
 | |
|     return true;
 | |
| }
 | |
| 
 | |
| static void qemu_start_incoming_migration(const char *uri, bool has_channels,
 | |
|                                           MigrationChannelList *channels,
 | |
|                                           Error **errp)
 | |
| {
 | |
|     g_autoptr(MigrationChannel) channel = NULL;
 | |
|     MigrationAddress *addr = NULL;
 | |
|     MigrationIncomingState *mis = migration_incoming_get_current();
 | |
| 
 | |
|     /*
 | |
|      * Having preliminary checks for uri and channel
 | |
|      */
 | |
|     if (!uri == !channels) {
 | |
|         error_setg(errp, "need either 'uri' or 'channels' argument");
 | |
|         return;
 | |
|     }
 | |
| 
 | |
|     if (channels) {
 | |
|         /* To verify that Migrate channel list has only item */
 | |
|         if (channels->next) {
 | |
|             error_setg(errp, "Channel list has more than one entries");
 | |
|             return;
 | |
|         }
 | |
|         addr = channels->value->addr;
 | |
|     }
 | |
| 
 | |
|     if (uri) {
 | |
|         /* caller uses the old URI syntax */
 | |
|         if (!migrate_uri_parse(uri, &channel, errp)) {
 | |
|             return;
 | |
|         }
 | |
|         addr = channel->addr;
 | |
|     }
 | |
| 
 | |
|     /* transport mechanism not suitable for migration? */
 | |
|     if (!migration_channels_and_transport_compatible(addr, errp)) {
 | |
|         return;
 | |
|     }
 | |
| 
 | |
|     migrate_set_state(&mis->state, MIGRATION_STATUS_NONE,
 | |
|                       MIGRATION_STATUS_SETUP);
 | |
| 
 | |
|     if (addr->transport == MIGRATION_ADDRESS_TYPE_SOCKET) {
 | |
|         SocketAddress *saddr = &addr->u.socket;
 | |
|         if (saddr->type == SOCKET_ADDRESS_TYPE_INET ||
 | |
|             saddr->type == SOCKET_ADDRESS_TYPE_UNIX ||
 | |
|             saddr->type == SOCKET_ADDRESS_TYPE_VSOCK) {
 | |
|             socket_start_incoming_migration(saddr, errp);
 | |
|         } else if (saddr->type == SOCKET_ADDRESS_TYPE_FD) {
 | |
|             fd_start_incoming_migration(saddr->u.fd.str, errp);
 | |
|         }
 | |
| #ifdef CONFIG_RDMA
 | |
|     } else if (addr->transport == MIGRATION_ADDRESS_TYPE_RDMA) {
 | |
|         if (migrate_compress()) {
 | |
|             error_setg(errp, "RDMA and compression can't be used together");
 | |
|             return;
 | |
|         }
 | |
|         if (migrate_xbzrle()) {
 | |
|             error_setg(errp, "RDMA and XBZRLE can't be used together");
 | |
|             return;
 | |
|         }
 | |
|         if (migrate_multifd()) {
 | |
|             error_setg(errp, "RDMA and multifd can't be used together");
 | |
|             return;
 | |
|         }
 | |
|         rdma_start_incoming_migration(&addr->u.rdma, errp);
 | |
| #endif
 | |
|     } else if (addr->transport == MIGRATION_ADDRESS_TYPE_EXEC) {
 | |
|         exec_start_incoming_migration(addr->u.exec.args, errp);
 | |
|     } else if (addr->transport == MIGRATION_ADDRESS_TYPE_FILE) {
 | |
|         file_start_incoming_migration(&addr->u.file, errp);
 | |
|     } else {
 | |
|         error_setg(errp, "unknown migration protocol: %s", uri);
 | |
|     }
 | |
| }
 | |
| 
 | |
| static void process_incoming_migration_bh(void *opaque)
 | |
| {
 | |
|     Error *local_err = NULL;
 | |
|     MigrationIncomingState *mis = opaque;
 | |
| 
 | |
|     trace_vmstate_downtime_checkpoint("dst-precopy-bh-enter");
 | |
| 
 | |
|     /* If capability late_block_activate is set:
 | |
|      * Only fire up the block code now if we're going to restart the
 | |
|      * VM, else 'cont' will do it.
 | |
|      * This causes file locking to happen; so we don't want it to happen
 | |
|      * unless we really are starting the VM.
 | |
|      */
 | |
|     if (!migrate_late_block_activate() ||
 | |
|          (autostart && (!global_state_received() ||
 | |
|             runstate_is_live(global_state_get_runstate())))) {
 | |
|         /* Make sure all file formats throw away their mutable metadata.
 | |
|          * If we get an error here, just don't restart the VM yet. */
 | |
|         bdrv_activate_all(&local_err);
 | |
|         if (local_err) {
 | |
|             error_report_err(local_err);
 | |
|             local_err = NULL;
 | |
|             autostart = false;
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     /*
 | |
|      * This must happen after all error conditions are dealt with and
 | |
|      * we're sure the VM is going to be running on this host.
 | |
|      */
 | |
|     qemu_announce_self(&mis->announce_timer, migrate_announce_params());
 | |
| 
 | |
|     trace_vmstate_downtime_checkpoint("dst-precopy-bh-announced");
 | |
| 
 | |
|     multifd_recv_shutdown();
 | |
| 
 | |
|     dirty_bitmap_mig_before_vm_start();
 | |
| 
 | |
|     if (!global_state_received() ||
 | |
|         runstate_is_live(global_state_get_runstate())) {
 | |
|         if (autostart) {
 | |
|             vm_start();
 | |
|         } else {
 | |
|             runstate_set(RUN_STATE_PAUSED);
 | |
|         }
 | |
|     } else if (migration_incoming_colo_enabled()) {
 | |
|         migration_incoming_disable_colo();
 | |
|         vm_start();
 | |
|     } else {
 | |
|         runstate_set(global_state_get_runstate());
 | |
|     }
 | |
|     trace_vmstate_downtime_checkpoint("dst-precopy-bh-vm-started");
 | |
|     /*
 | |
|      * This must happen after any state changes since as soon as an external
 | |
|      * observer sees this event they might start to prod at the VM assuming
 | |
|      * it's ready to use.
 | |
|      */
 | |
|     migrate_set_state(&mis->state, MIGRATION_STATUS_ACTIVE,
 | |
|                       MIGRATION_STATUS_COMPLETED);
 | |
|     migration_incoming_state_destroy();
 | |
| }
 | |
| 
 | |
| static void coroutine_fn
 | |
| process_incoming_migration_co(void *opaque)
 | |
| {
 | |
|     MigrationIncomingState *mis = migration_incoming_get_current();
 | |
|     PostcopyState ps;
 | |
|     int ret;
 | |
| 
 | |
|     assert(mis->from_src_file);
 | |
| 
 | |
|     if (compress_threads_load_setup(mis->from_src_file)) {
 | |
|         error_report("Failed to setup decompress threads");
 | |
|         goto fail;
 | |
|     }
 | |
| 
 | |
|     mis->largest_page_size = qemu_ram_pagesize_largest();
 | |
|     postcopy_state_set(POSTCOPY_INCOMING_NONE);
 | |
|     migrate_set_state(&mis->state, MIGRATION_STATUS_SETUP,
 | |
|                       MIGRATION_STATUS_ACTIVE);
 | |
| 
 | |
|     mis->loadvm_co = qemu_coroutine_self();
 | |
|     ret = qemu_loadvm_state(mis->from_src_file);
 | |
|     mis->loadvm_co = NULL;
 | |
| 
 | |
|     trace_vmstate_downtime_checkpoint("dst-precopy-loadvm-completed");
 | |
| 
 | |
|     ps = postcopy_state_get();
 | |
|     trace_process_incoming_migration_co_end(ret, ps);
 | |
|     if (ps != POSTCOPY_INCOMING_NONE) {
 | |
|         if (ps == POSTCOPY_INCOMING_ADVISE) {
 | |
|             /*
 | |
|              * Where a migration had postcopy enabled (and thus went to advise)
 | |
|              * but managed to complete within the precopy period, we can use
 | |
|              * the normal exit.
 | |
|              */
 | |
|             postcopy_ram_incoming_cleanup(mis);
 | |
|         } else if (ret >= 0) {
 | |
|             /*
 | |
|              * Postcopy was started, cleanup should happen at the end of the
 | |
|              * postcopy thread.
 | |
|              */
 | |
|             trace_process_incoming_migration_co_postcopy_end_main();
 | |
|             return;
 | |
|         }
 | |
|         /* Else if something went wrong then just fall out of the normal exit */
 | |
|     }
 | |
| 
 | |
|     if (ret < 0) {
 | |
|         MigrationState *s = migrate_get_current();
 | |
| 
 | |
|         if (migrate_has_error(s)) {
 | |
|             WITH_QEMU_LOCK_GUARD(&s->error_mutex) {
 | |
|                 error_report_err(s->error);
 | |
|             }
 | |
|         }
 | |
|         error_report("load of migration failed: %s", strerror(-ret));
 | |
|         goto fail;
 | |
|     }
 | |
| 
 | |
|     if (colo_incoming_co() < 0) {
 | |
|         goto fail;
 | |
|     }
 | |
| 
 | |
|     migration_bh_schedule(process_incoming_migration_bh, mis);
 | |
|     return;
 | |
| fail:
 | |
|     migrate_set_state(&mis->state, MIGRATION_STATUS_ACTIVE,
 | |
|                       MIGRATION_STATUS_FAILED);
 | |
|     qemu_fclose(mis->from_src_file);
 | |
| 
 | |
|     multifd_recv_cleanup();
 | |
|     compress_threads_load_cleanup();
 | |
| 
 | |
|     exit(EXIT_FAILURE);
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * migration_incoming_setup: Setup incoming migration
 | |
|  * @f: file for main migration channel
 | |
|  */
 | |
| static void migration_incoming_setup(QEMUFile *f)
 | |
| {
 | |
|     MigrationIncomingState *mis = migration_incoming_get_current();
 | |
| 
 | |
|     if (!mis->from_src_file) {
 | |
|         mis->from_src_file = f;
 | |
|     }
 | |
|     qemu_file_set_blocking(f, false);
 | |
| }
 | |
| 
 | |
| void migration_incoming_process(void)
 | |
| {
 | |
|     Coroutine *co = qemu_coroutine_create(process_incoming_migration_co, NULL);
 | |
|     qemu_coroutine_enter(co);
 | |
| }
 | |
| 
 | |
| /* Returns true if recovered from a paused migration, otherwise false */
 | |
| static bool postcopy_try_recover(void)
 | |
| {
 | |
|     MigrationIncomingState *mis = migration_incoming_get_current();
 | |
| 
 | |
|     if (mis->state == MIGRATION_STATUS_POSTCOPY_PAUSED) {
 | |
|         /* Resumed from a paused postcopy migration */
 | |
| 
 | |
|         /* This should be set already in migration_incoming_setup() */
 | |
|         assert(mis->from_src_file);
 | |
|         /* Postcopy has standalone thread to do vm load */
 | |
|         qemu_file_set_blocking(mis->from_src_file, true);
 | |
| 
 | |
|         /* Re-configure the return path */
 | |
|         mis->to_src_file = qemu_file_get_return_path(mis->from_src_file);
 | |
| 
 | |
|         migrate_set_state(&mis->state, MIGRATION_STATUS_POSTCOPY_PAUSED,
 | |
|                           MIGRATION_STATUS_POSTCOPY_RECOVER);
 | |
| 
 | |
|         /*
 | |
|          * Here, we only wake up the main loading thread (while the
 | |
|          * rest threads will still be waiting), so that we can receive
 | |
|          * commands from source now, and answer it if needed. The
 | |
|          * rest threads will be woken up afterwards until we are sure
 | |
|          * that source is ready to reply to page requests.
 | |
|          */
 | |
|         qemu_sem_post(&mis->postcopy_pause_sem_dst);
 | |
|         return true;
 | |
|     }
 | |
| 
 | |
|     return false;
 | |
| }
 | |
| 
 | |
| void migration_fd_process_incoming(QEMUFile *f)
 | |
| {
 | |
|     migration_incoming_setup(f);
 | |
|     if (postcopy_try_recover()) {
 | |
|         return;
 | |
|     }
 | |
|     migration_incoming_process();
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Returns true when we want to start a new incoming migration process,
 | |
|  * false otherwise.
 | |
|  */
 | |
| static bool migration_should_start_incoming(bool main_channel)
 | |
| {
 | |
|     /* Multifd doesn't start unless all channels are established */
 | |
|     if (migrate_multifd()) {
 | |
|         return migration_has_all_channels();
 | |
|     }
 | |
| 
 | |
|     /* Preempt channel only starts when the main channel is created */
 | |
|     if (migrate_postcopy_preempt()) {
 | |
|         return main_channel;
 | |
|     }
 | |
| 
 | |
|     /*
 | |
|      * For all the rest types of migration, we should only reach here when
 | |
|      * it's the main channel that's being created, and we should always
 | |
|      * proceed with this channel.
 | |
|      */
 | |
|     assert(main_channel);
 | |
|     return true;
 | |
| }
 | |
| 
 | |
| void migration_ioc_process_incoming(QIOChannel *ioc, Error **errp)
 | |
| {
 | |
|     MigrationIncomingState *mis = migration_incoming_get_current();
 | |
|     Error *local_err = NULL;
 | |
|     QEMUFile *f;
 | |
|     bool default_channel = true;
 | |
|     uint32_t channel_magic = 0;
 | |
|     int ret = 0;
 | |
| 
 | |
|     if (migrate_multifd() && !migrate_mapped_ram() &&
 | |
|         !migrate_postcopy_ram() &&
 | |
|         qio_channel_has_feature(ioc, QIO_CHANNEL_FEATURE_READ_MSG_PEEK)) {
 | |
|         /*
 | |
|          * With multiple channels, it is possible that we receive channels
 | |
|          * out of order on destination side, causing incorrect mapping of
 | |
|          * source channels on destination side. Check channel MAGIC to
 | |
|          * decide type of channel. Please note this is best effort, postcopy
 | |
|          * preempt channel does not send any magic number so avoid it for
 | |
|          * postcopy live migration. Also tls live migration already does
 | |
|          * tls handshake while initializing main channel so with tls this
 | |
|          * issue is not possible.
 | |
|          */
 | |
|         ret = migration_channel_read_peek(ioc, (void *)&channel_magic,
 | |
|                                           sizeof(channel_magic), errp);
 | |
| 
 | |
|         if (ret != 0) {
 | |
|             return;
 | |
|         }
 | |
| 
 | |
|         default_channel = (channel_magic == cpu_to_be32(QEMU_VM_FILE_MAGIC));
 | |
|     } else {
 | |
|         default_channel = !mis->from_src_file;
 | |
|     }
 | |
| 
 | |
|     if (multifd_recv_setup(errp) != 0) {
 | |
|         return;
 | |
|     }
 | |
| 
 | |
|     if (default_channel) {
 | |
|         f = qemu_file_new_input(ioc);
 | |
|         migration_incoming_setup(f);
 | |
|     } else {
 | |
|         /* Multiple connections */
 | |
|         assert(migration_needs_multiple_sockets());
 | |
|         if (migrate_multifd()) {
 | |
|             multifd_recv_new_channel(ioc, &local_err);
 | |
|         } else {
 | |
|             assert(migrate_postcopy_preempt());
 | |
|             f = qemu_file_new_input(ioc);
 | |
|             postcopy_preempt_new_channel(mis, f);
 | |
|         }
 | |
|         if (local_err) {
 | |
|             error_propagate(errp, local_err);
 | |
|             return;
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     if (migration_should_start_incoming(default_channel)) {
 | |
|         /* If it's a recovery, we're done */
 | |
|         if (postcopy_try_recover()) {
 | |
|             return;
 | |
|         }
 | |
|         migration_incoming_process();
 | |
|     }
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * @migration_has_all_channels: We have received all channels that we need
 | |
|  *
 | |
|  * Returns true when we have got connections to all the channels that
 | |
|  * we need for migration.
 | |
|  */
 | |
| bool migration_has_all_channels(void)
 | |
| {
 | |
|     MigrationIncomingState *mis = migration_incoming_get_current();
 | |
| 
 | |
|     if (!mis->from_src_file) {
 | |
|         return false;
 | |
|     }
 | |
| 
 | |
|     if (migrate_multifd()) {
 | |
|         return multifd_recv_all_channels_created();
 | |
|     }
 | |
| 
 | |
|     if (migrate_postcopy_preempt()) {
 | |
|         return mis->postcopy_qemufile_dst != NULL;
 | |
|     }
 | |
| 
 | |
|     return true;
 | |
| }
 | |
| 
 | |
| int migrate_send_rp_switchover_ack(MigrationIncomingState *mis)
 | |
| {
 | |
|     return migrate_send_rp_message(mis, MIG_RP_MSG_SWITCHOVER_ACK, 0, NULL);
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Send a 'SHUT' message on the return channel with the given value
 | |
|  * to indicate that we've finished with the RP.  Non-0 value indicates
 | |
|  * error.
 | |
|  */
 | |
| void migrate_send_rp_shut(MigrationIncomingState *mis,
 | |
|                           uint32_t value)
 | |
| {
 | |
|     uint32_t buf;
 | |
| 
 | |
|     buf = cpu_to_be32(value);
 | |
|     migrate_send_rp_message(mis, MIG_RP_MSG_SHUT, sizeof(buf), &buf);
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Send a 'PONG' message on the return channel with the given value
 | |
|  * (normally in response to a 'PING')
 | |
|  */
 | |
| void migrate_send_rp_pong(MigrationIncomingState *mis,
 | |
|                           uint32_t value)
 | |
| {
 | |
|     uint32_t buf;
 | |
| 
 | |
|     buf = cpu_to_be32(value);
 | |
|     migrate_send_rp_message(mis, MIG_RP_MSG_PONG, sizeof(buf), &buf);
 | |
| }
 | |
| 
 | |
| void migrate_send_rp_recv_bitmap(MigrationIncomingState *mis,
 | |
|                                  char *block_name)
 | |
| {
 | |
|     char buf[512];
 | |
|     int len;
 | |
|     int64_t res;
 | |
| 
 | |
|     /*
 | |
|      * First, we send the header part. It contains only the len of
 | |
|      * idstr, and the idstr itself.
 | |
|      */
 | |
|     len = strlen(block_name);
 | |
|     buf[0] = len;
 | |
|     memcpy(buf + 1, block_name, len);
 | |
| 
 | |
|     if (mis->state != MIGRATION_STATUS_POSTCOPY_RECOVER) {
 | |
|         error_report("%s: MSG_RP_RECV_BITMAP only used for recovery",
 | |
|                      __func__);
 | |
|         return;
 | |
|     }
 | |
| 
 | |
|     migrate_send_rp_message(mis, MIG_RP_MSG_RECV_BITMAP, len + 1, buf);
 | |
| 
 | |
|     /*
 | |
|      * Next, we dump the received bitmap to the stream.
 | |
|      *
 | |
|      * TODO: currently we are safe since we are the only one that is
 | |
|      * using the to_src_file handle (fault thread is still paused),
 | |
|      * and it's ok even not taking the mutex. However the best way is
 | |
|      * to take the lock before sending the message header, and release
 | |
|      * the lock after sending the bitmap.
 | |
|      */
 | |
|     qemu_mutex_lock(&mis->rp_mutex);
 | |
|     res = ramblock_recv_bitmap_send(mis->to_src_file, block_name);
 | |
|     qemu_mutex_unlock(&mis->rp_mutex);
 | |
| 
 | |
|     trace_migrate_send_rp_recv_bitmap(block_name, res);
 | |
| }
 | |
| 
 | |
| void migrate_send_rp_resume_ack(MigrationIncomingState *mis, uint32_t value)
 | |
| {
 | |
|     uint32_t buf;
 | |
| 
 | |
|     buf = cpu_to_be32(value);
 | |
|     migrate_send_rp_message(mis, MIG_RP_MSG_RESUME_ACK, sizeof(buf), &buf);
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Return true if we're already in the middle of a migration
 | |
|  * (i.e. any of the active or setup states)
 | |
|  */
 | |
| bool migration_is_setup_or_active(int state)
 | |
| {
 | |
|     switch (state) {
 | |
|     case MIGRATION_STATUS_ACTIVE:
 | |
|     case MIGRATION_STATUS_POSTCOPY_ACTIVE:
 | |
|     case MIGRATION_STATUS_POSTCOPY_PAUSED:
 | |
|     case MIGRATION_STATUS_POSTCOPY_RECOVER:
 | |
|     case MIGRATION_STATUS_SETUP:
 | |
|     case MIGRATION_STATUS_PRE_SWITCHOVER:
 | |
|     case MIGRATION_STATUS_DEVICE:
 | |
|     case MIGRATION_STATUS_WAIT_UNPLUG:
 | |
|     case MIGRATION_STATUS_COLO:
 | |
|         return true;
 | |
| 
 | |
|     default:
 | |
|         return false;
 | |
| 
 | |
|     }
 | |
| }
 | |
| 
 | |
| bool migration_is_running(int state)
 | |
| {
 | |
|     switch (state) {
 | |
|     case MIGRATION_STATUS_ACTIVE:
 | |
|     case MIGRATION_STATUS_POSTCOPY_ACTIVE:
 | |
|     case MIGRATION_STATUS_POSTCOPY_PAUSED:
 | |
|     case MIGRATION_STATUS_POSTCOPY_RECOVER:
 | |
|     case MIGRATION_STATUS_SETUP:
 | |
|     case MIGRATION_STATUS_PRE_SWITCHOVER:
 | |
|     case MIGRATION_STATUS_DEVICE:
 | |
|     case MIGRATION_STATUS_WAIT_UNPLUG:
 | |
|     case MIGRATION_STATUS_CANCELLING:
 | |
|         return true;
 | |
| 
 | |
|     default:
 | |
|         return false;
 | |
| 
 | |
|     }
 | |
| }
 | |
| 
 | |
| static bool migrate_show_downtime(MigrationState *s)
 | |
| {
 | |
|     return (s->state == MIGRATION_STATUS_COMPLETED) || migration_in_postcopy();
 | |
| }
 | |
| 
 | |
| static void populate_time_info(MigrationInfo *info, MigrationState *s)
 | |
| {
 | |
|     info->has_status = true;
 | |
|     info->has_setup_time = true;
 | |
|     info->setup_time = s->setup_time;
 | |
| 
 | |
|     if (s->state == MIGRATION_STATUS_COMPLETED) {
 | |
|         info->has_total_time = true;
 | |
|         info->total_time = s->total_time;
 | |
|     } else {
 | |
|         info->has_total_time = true;
 | |
|         info->total_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME) -
 | |
|                            s->start_time;
 | |
|     }
 | |
| 
 | |
|     if (migrate_show_downtime(s)) {
 | |
|         info->has_downtime = true;
 | |
|         info->downtime = s->downtime;
 | |
|     } else {
 | |
|         info->has_expected_downtime = true;
 | |
|         info->expected_downtime = s->expected_downtime;
 | |
|     }
 | |
| }
 | |
| 
 | |
| static void populate_ram_info(MigrationInfo *info, MigrationState *s)
 | |
| {
 | |
|     size_t page_size = qemu_target_page_size();
 | |
| 
 | |
|     info->ram = g_malloc0(sizeof(*info->ram));
 | |
|     info->ram->transferred = migration_transferred_bytes();
 | |
|     info->ram->total = ram_bytes_total();
 | |
|     info->ram->duplicate = stat64_get(&mig_stats.zero_pages);
 | |
|     /* legacy value.  It is not used anymore */
 | |
|     info->ram->skipped = 0;
 | |
|     info->ram->normal = stat64_get(&mig_stats.normal_pages);
 | |
|     info->ram->normal_bytes = info->ram->normal * page_size;
 | |
|     info->ram->mbps = s->mbps;
 | |
|     info->ram->dirty_sync_count =
 | |
|         stat64_get(&mig_stats.dirty_sync_count);
 | |
|     info->ram->dirty_sync_missed_zero_copy =
 | |
|         stat64_get(&mig_stats.dirty_sync_missed_zero_copy);
 | |
|     info->ram->postcopy_requests =
 | |
|         stat64_get(&mig_stats.postcopy_requests);
 | |
|     info->ram->page_size = page_size;
 | |
|     info->ram->multifd_bytes = stat64_get(&mig_stats.multifd_bytes);
 | |
|     info->ram->pages_per_second = s->pages_per_second;
 | |
|     info->ram->precopy_bytes = stat64_get(&mig_stats.precopy_bytes);
 | |
|     info->ram->downtime_bytes = stat64_get(&mig_stats.downtime_bytes);
 | |
|     info->ram->postcopy_bytes = stat64_get(&mig_stats.postcopy_bytes);
 | |
| 
 | |
|     if (migrate_xbzrle()) {
 | |
|         info->xbzrle_cache = g_malloc0(sizeof(*info->xbzrle_cache));
 | |
|         info->xbzrle_cache->cache_size = migrate_xbzrle_cache_size();
 | |
|         info->xbzrle_cache->bytes = xbzrle_counters.bytes;
 | |
|         info->xbzrle_cache->pages = xbzrle_counters.pages;
 | |
|         info->xbzrle_cache->cache_miss = xbzrle_counters.cache_miss;
 | |
|         info->xbzrle_cache->cache_miss_rate = xbzrle_counters.cache_miss_rate;
 | |
|         info->xbzrle_cache->encoding_rate = xbzrle_counters.encoding_rate;
 | |
|         info->xbzrle_cache->overflow = xbzrle_counters.overflow;
 | |
|     }
 | |
| 
 | |
|     populate_compress(info);
 | |
| 
 | |
|     if (cpu_throttle_active()) {
 | |
|         info->has_cpu_throttle_percentage = true;
 | |
|         info->cpu_throttle_percentage = cpu_throttle_get_percentage();
 | |
|     }
 | |
| 
 | |
|     if (s->state != MIGRATION_STATUS_COMPLETED) {
 | |
|         info->ram->remaining = ram_bytes_remaining();
 | |
|         info->ram->dirty_pages_rate =
 | |
|            stat64_get(&mig_stats.dirty_pages_rate);
 | |
|     }
 | |
| 
 | |
|     if (migrate_dirty_limit() && dirtylimit_in_service()) {
 | |
|         info->has_dirty_limit_throttle_time_per_round = true;
 | |
|         info->dirty_limit_throttle_time_per_round =
 | |
|                             dirtylimit_throttle_time_per_round();
 | |
| 
 | |
|         info->has_dirty_limit_ring_full_time = true;
 | |
|         info->dirty_limit_ring_full_time = dirtylimit_ring_full_time();
 | |
|     }
 | |
| }
 | |
| 
 | |
| static void populate_disk_info(MigrationInfo *info)
 | |
| {
 | |
|     if (blk_mig_active()) {
 | |
|         info->disk = g_malloc0(sizeof(*info->disk));
 | |
|         info->disk->transferred = blk_mig_bytes_transferred();
 | |
|         info->disk->remaining = blk_mig_bytes_remaining();
 | |
|         info->disk->total = blk_mig_bytes_total();
 | |
|     }
 | |
| }
 | |
| 
 | |
| static void fill_source_migration_info(MigrationInfo *info)
 | |
| {
 | |
|     MigrationState *s = migrate_get_current();
 | |
|     int state = qatomic_read(&s->state);
 | |
|     GSList *cur_blocker = migration_blockers[migrate_mode()];
 | |
| 
 | |
|     info->blocked_reasons = NULL;
 | |
| 
 | |
|     /*
 | |
|      * There are two types of reasons a migration might be blocked;
 | |
|      * a) devices marked in VMState as non-migratable, and
 | |
|      * b) Explicit migration blockers
 | |
|      * We need to add both of them here.
 | |
|      */
 | |
|     qemu_savevm_non_migratable_list(&info->blocked_reasons);
 | |
| 
 | |
|     while (cur_blocker) {
 | |
|         QAPI_LIST_PREPEND(info->blocked_reasons,
 | |
|                           g_strdup(error_get_pretty(cur_blocker->data)));
 | |
|         cur_blocker = g_slist_next(cur_blocker);
 | |
|     }
 | |
|     info->has_blocked_reasons = info->blocked_reasons != NULL;
 | |
| 
 | |
|     switch (state) {
 | |
|     case MIGRATION_STATUS_NONE:
 | |
|         /* no migration has happened ever */
 | |
|         /* do not overwrite destination migration status */
 | |
|         return;
 | |
|     case MIGRATION_STATUS_SETUP:
 | |
|         info->has_status = true;
 | |
|         info->has_total_time = false;
 | |
|         break;
 | |
|     case MIGRATION_STATUS_ACTIVE:
 | |
|     case MIGRATION_STATUS_CANCELLING:
 | |
|     case MIGRATION_STATUS_POSTCOPY_ACTIVE:
 | |
|     case MIGRATION_STATUS_PRE_SWITCHOVER:
 | |
|     case MIGRATION_STATUS_DEVICE:
 | |
|     case MIGRATION_STATUS_POSTCOPY_PAUSED:
 | |
|     case MIGRATION_STATUS_POSTCOPY_RECOVER:
 | |
|         /* TODO add some postcopy stats */
 | |
|         populate_time_info(info, s);
 | |
|         populate_ram_info(info, s);
 | |
|         populate_disk_info(info);
 | |
|         migration_populate_vfio_info(info);
 | |
|         break;
 | |
|     case MIGRATION_STATUS_COLO:
 | |
|         info->has_status = true;
 | |
|         /* TODO: display COLO specific information (checkpoint info etc.) */
 | |
|         break;
 | |
|     case MIGRATION_STATUS_COMPLETED:
 | |
|         populate_time_info(info, s);
 | |
|         populate_ram_info(info, s);
 | |
|         migration_populate_vfio_info(info);
 | |
|         break;
 | |
|     case MIGRATION_STATUS_FAILED:
 | |
|         info->has_status = true;
 | |
|         break;
 | |
|     case MIGRATION_STATUS_CANCELLED:
 | |
|         info->has_status = true;
 | |
|         break;
 | |
|     case MIGRATION_STATUS_WAIT_UNPLUG:
 | |
|         info->has_status = true;
 | |
|         break;
 | |
|     }
 | |
|     info->status = state;
 | |
| 
 | |
|     QEMU_LOCK_GUARD(&s->error_mutex);
 | |
|     if (s->error) {
 | |
|         info->error_desc = g_strdup(error_get_pretty(s->error));
 | |
|     }
 | |
| }
 | |
| 
 | |
| static void fill_destination_migration_info(MigrationInfo *info)
 | |
| {
 | |
|     MigrationIncomingState *mis = migration_incoming_get_current();
 | |
| 
 | |
|     if (mis->socket_address_list) {
 | |
|         info->has_socket_address = true;
 | |
|         info->socket_address =
 | |
|             QAPI_CLONE(SocketAddressList, mis->socket_address_list);
 | |
|     }
 | |
| 
 | |
|     switch (mis->state) {
 | |
|     case MIGRATION_STATUS_NONE:
 | |
|         return;
 | |
|     case MIGRATION_STATUS_SETUP:
 | |
|     case MIGRATION_STATUS_CANCELLING:
 | |
|     case MIGRATION_STATUS_CANCELLED:
 | |
|     case MIGRATION_STATUS_ACTIVE:
 | |
|     case MIGRATION_STATUS_POSTCOPY_ACTIVE:
 | |
|     case MIGRATION_STATUS_POSTCOPY_PAUSED:
 | |
|     case MIGRATION_STATUS_POSTCOPY_RECOVER:
 | |
|     case MIGRATION_STATUS_FAILED:
 | |
|     case MIGRATION_STATUS_COLO:
 | |
|         info->has_status = true;
 | |
|         break;
 | |
|     case MIGRATION_STATUS_COMPLETED:
 | |
|         info->has_status = true;
 | |
|         fill_destination_postcopy_migration_info(info);
 | |
|         break;
 | |
|     }
 | |
|     info->status = mis->state;
 | |
| }
 | |
| 
 | |
| MigrationInfo *qmp_query_migrate(Error **errp)
 | |
| {
 | |
|     MigrationInfo *info = g_malloc0(sizeof(*info));
 | |
| 
 | |
|     fill_destination_migration_info(info);
 | |
|     fill_source_migration_info(info);
 | |
| 
 | |
|     return info;
 | |
| }
 | |
| 
 | |
| void qmp_migrate_start_postcopy(Error **errp)
 | |
| {
 | |
|     MigrationState *s = migrate_get_current();
 | |
| 
 | |
|     if (!migrate_postcopy()) {
 | |
|         error_setg(errp, "Enable postcopy with migrate_set_capability before"
 | |
|                          " the start of migration");
 | |
|         return;
 | |
|     }
 | |
| 
 | |
|     if (s->state == MIGRATION_STATUS_NONE) {
 | |
|         error_setg(errp, "Postcopy must be started after migration has been"
 | |
|                          " started");
 | |
|         return;
 | |
|     }
 | |
|     /*
 | |
|      * we don't error if migration has finished since that would be racy
 | |
|      * with issuing this command.
 | |
|      */
 | |
|     qatomic_set(&s->start_postcopy, true);
 | |
| }
 | |
| 
 | |
| /* shared migration helpers */
 | |
| 
 | |
| void migrate_set_state(int *state, int old_state, int new_state)
 | |
| {
 | |
|     assert(new_state < MIGRATION_STATUS__MAX);
 | |
|     if (qatomic_cmpxchg(state, old_state, new_state) == old_state) {
 | |
|         trace_migrate_set_state(MigrationStatus_str(new_state));
 | |
|         migrate_generate_event(new_state);
 | |
|     }
 | |
| }
 | |
| 
 | |
| static void migrate_fd_cleanup(MigrationState *s)
 | |
| {
 | |
|     MigrationEventType type;
 | |
| 
 | |
|     g_free(s->hostname);
 | |
|     s->hostname = NULL;
 | |
|     json_writer_free(s->vmdesc);
 | |
|     s->vmdesc = NULL;
 | |
| 
 | |
|     qemu_savevm_state_cleanup();
 | |
| 
 | |
|     close_return_path_on_source(s);
 | |
| 
 | |
|     if (s->to_dst_file) {
 | |
|         QEMUFile *tmp;
 | |
| 
 | |
|         trace_migrate_fd_cleanup();
 | |
|         bql_unlock();
 | |
|         if (s->migration_thread_running) {
 | |
|             qemu_thread_join(&s->thread);
 | |
|             s->migration_thread_running = false;
 | |
|         }
 | |
|         bql_lock();
 | |
| 
 | |
|         multifd_send_shutdown();
 | |
|         qemu_mutex_lock(&s->qemu_file_lock);
 | |
|         tmp = s->to_dst_file;
 | |
|         s->to_dst_file = NULL;
 | |
|         qemu_mutex_unlock(&s->qemu_file_lock);
 | |
|         /*
 | |
|          * Close the file handle without the lock to make sure the
 | |
|          * critical section won't block for long.
 | |
|          */
 | |
|         migration_ioc_unregister_yank_from_file(tmp);
 | |
|         qemu_fclose(tmp);
 | |
|     }
 | |
| 
 | |
|     assert(!migration_is_active(s));
 | |
| 
 | |
|     if (s->state == MIGRATION_STATUS_CANCELLING) {
 | |
|         migrate_set_state(&s->state, MIGRATION_STATUS_CANCELLING,
 | |
|                           MIGRATION_STATUS_CANCELLED);
 | |
|     }
 | |
| 
 | |
|     if (s->error) {
 | |
|         /* It is used on info migrate.  We can't free it */
 | |
|         error_report_err(error_copy(s->error));
 | |
|     }
 | |
|     type = migration_has_failed(s) ? MIG_EVENT_PRECOPY_FAILED :
 | |
|                                      MIG_EVENT_PRECOPY_DONE;
 | |
|     migration_call_notifiers(s, type, NULL);
 | |
|     block_cleanup_parameters();
 | |
|     yank_unregister_instance(MIGRATION_YANK_INSTANCE);
 | |
| }
 | |
| 
 | |
| static void migrate_fd_cleanup_bh(void *opaque)
 | |
| {
 | |
|     migrate_fd_cleanup(opaque);
 | |
| }
 | |
| 
 | |
| void migrate_set_error(MigrationState *s, const Error *error)
 | |
| {
 | |
|     QEMU_LOCK_GUARD(&s->error_mutex);
 | |
|     if (!s->error) {
 | |
|         s->error = error_copy(error);
 | |
|     }
 | |
| }
 | |
| 
 | |
| bool migrate_has_error(MigrationState *s)
 | |
| {
 | |
|     /* The lock is not helpful here, but still follow the rule */
 | |
|     QEMU_LOCK_GUARD(&s->error_mutex);
 | |
|     return qatomic_read(&s->error);
 | |
| }
 | |
| 
 | |
| static void migrate_error_free(MigrationState *s)
 | |
| {
 | |
|     QEMU_LOCK_GUARD(&s->error_mutex);
 | |
|     if (s->error) {
 | |
|         error_free(s->error);
 | |
|         s->error = NULL;
 | |
|     }
 | |
| }
 | |
| 
 | |
| static void migrate_fd_error(MigrationState *s, const Error *error)
 | |
| {
 | |
|     trace_migrate_fd_error(error_get_pretty(error));
 | |
|     assert(s->to_dst_file == NULL);
 | |
|     migrate_set_state(&s->state, MIGRATION_STATUS_SETUP,
 | |
|                       MIGRATION_STATUS_FAILED);
 | |
|     migrate_set_error(s, error);
 | |
| }
 | |
| 
 | |
| static void migrate_fd_cancel(MigrationState *s)
 | |
| {
 | |
|     int old_state ;
 | |
| 
 | |
|     trace_migrate_fd_cancel();
 | |
| 
 | |
|     WITH_QEMU_LOCK_GUARD(&s->qemu_file_lock) {
 | |
|         if (s->rp_state.from_dst_file) {
 | |
|             /* shutdown the rp socket, so causing the rp thread to shutdown */
 | |
|             qemu_file_shutdown(s->rp_state.from_dst_file);
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     do {
 | |
|         old_state = s->state;
 | |
|         if (!migration_is_running(old_state)) {
 | |
|             break;
 | |
|         }
 | |
|         /* If the migration is paused, kick it out of the pause */
 | |
|         if (old_state == MIGRATION_STATUS_PRE_SWITCHOVER) {
 | |
|             qemu_sem_post(&s->pause_sem);
 | |
|         }
 | |
|         migrate_set_state(&s->state, old_state, MIGRATION_STATUS_CANCELLING);
 | |
|     } while (s->state != MIGRATION_STATUS_CANCELLING);
 | |
| 
 | |
|     /*
 | |
|      * If we're unlucky the migration code might be stuck somewhere in a
 | |
|      * send/write while the network has failed and is waiting to timeout;
 | |
|      * if we've got shutdown(2) available then we can force it to quit.
 | |
|      */
 | |
|     if (s->state == MIGRATION_STATUS_CANCELLING) {
 | |
|         WITH_QEMU_LOCK_GUARD(&s->qemu_file_lock) {
 | |
|             if (s->to_dst_file) {
 | |
|                 qemu_file_shutdown(s->to_dst_file);
 | |
|             }
 | |
|         }
 | |
|     }
 | |
|     if (s->state == MIGRATION_STATUS_CANCELLING && s->block_inactive) {
 | |
|         Error *local_err = NULL;
 | |
| 
 | |
|         bdrv_activate_all(&local_err);
 | |
|         if (local_err) {
 | |
|             error_report_err(local_err);
 | |
|         } else {
 | |
|             s->block_inactive = false;
 | |
|         }
 | |
|     }
 | |
| }
 | |
| 
 | |
| void migration_add_notifier_mode(NotifierWithReturn *notify,
 | |
|                                  MigrationNotifyFunc func, MigMode mode)
 | |
| {
 | |
|     notify->notify = (NotifierWithReturnFunc)func;
 | |
|     notifier_with_return_list_add(&migration_state_notifiers[mode], notify);
 | |
| }
 | |
| 
 | |
| void migration_add_notifier(NotifierWithReturn *notify,
 | |
|                             MigrationNotifyFunc func)
 | |
| {
 | |
|     migration_add_notifier_mode(notify, func, MIG_MODE_NORMAL);
 | |
| }
 | |
| 
 | |
| void migration_remove_notifier(NotifierWithReturn *notify)
 | |
| {
 | |
|     if (notify->notify) {
 | |
|         notifier_with_return_remove(notify);
 | |
|         notify->notify = NULL;
 | |
|     }
 | |
| }
 | |
| 
 | |
| int migration_call_notifiers(MigrationState *s, MigrationEventType type,
 | |
|                              Error **errp)
 | |
| {
 | |
|     MigMode mode = s->parameters.mode;
 | |
|     MigrationEvent e;
 | |
|     int ret;
 | |
| 
 | |
|     e.type = type;
 | |
|     ret = notifier_with_return_list_notify(&migration_state_notifiers[mode],
 | |
|                                            &e, errp);
 | |
|     assert(!ret || type == MIG_EVENT_PRECOPY_SETUP);
 | |
|     return ret;
 | |
| }
 | |
| 
 | |
| bool migration_in_setup(MigrationState *s)
 | |
| {
 | |
|     return s->state == MIGRATION_STATUS_SETUP;
 | |
| }
 | |
| 
 | |
| bool migration_has_finished(MigrationState *s)
 | |
| {
 | |
|     return s->state == MIGRATION_STATUS_COMPLETED;
 | |
| }
 | |
| 
 | |
| bool migration_has_failed(MigrationState *s)
 | |
| {
 | |
|     return (s->state == MIGRATION_STATUS_CANCELLED ||
 | |
|             s->state == MIGRATION_STATUS_FAILED);
 | |
| }
 | |
| 
 | |
| bool migration_in_postcopy(void)
 | |
| {
 | |
|     MigrationState *s = migrate_get_current();
 | |
| 
 | |
|     switch (s->state) {
 | |
|     case MIGRATION_STATUS_POSTCOPY_ACTIVE:
 | |
|     case MIGRATION_STATUS_POSTCOPY_PAUSED:
 | |
|     case MIGRATION_STATUS_POSTCOPY_RECOVER:
 | |
|         return true;
 | |
|     default:
 | |
|         return false;
 | |
|     }
 | |
| }
 | |
| 
 | |
| bool migration_postcopy_is_alive(int state)
 | |
| {
 | |
|     switch (state) {
 | |
|     case MIGRATION_STATUS_POSTCOPY_ACTIVE:
 | |
|     case MIGRATION_STATUS_POSTCOPY_RECOVER:
 | |
|         return true;
 | |
|     default:
 | |
|         return false;
 | |
|     }
 | |
| }
 | |
| 
 | |
| bool migration_in_incoming_postcopy(void)
 | |
| {
 | |
|     PostcopyState ps = postcopy_state_get();
 | |
| 
 | |
|     return ps >= POSTCOPY_INCOMING_DISCARD && ps < POSTCOPY_INCOMING_END;
 | |
| }
 | |
| 
 | |
| bool migration_incoming_postcopy_advised(void)
 | |
| {
 | |
|     PostcopyState ps = postcopy_state_get();
 | |
| 
 | |
|     return ps >= POSTCOPY_INCOMING_ADVISE && ps < POSTCOPY_INCOMING_END;
 | |
| }
 | |
| 
 | |
| bool migration_in_bg_snapshot(void)
 | |
| {
 | |
|     MigrationState *s = migrate_get_current();
 | |
| 
 | |
|     return migrate_background_snapshot() &&
 | |
|             migration_is_setup_or_active(s->state);
 | |
| }
 | |
| 
 | |
| bool migration_is_idle(void)
 | |
| {
 | |
|     MigrationState *s = current_migration;
 | |
| 
 | |
|     if (!s) {
 | |
|         return true;
 | |
|     }
 | |
| 
 | |
|     switch (s->state) {
 | |
|     case MIGRATION_STATUS_NONE:
 | |
|     case MIGRATION_STATUS_CANCELLED:
 | |
|     case MIGRATION_STATUS_COMPLETED:
 | |
|     case MIGRATION_STATUS_FAILED:
 | |
|         return true;
 | |
|     case MIGRATION_STATUS_SETUP:
 | |
|     case MIGRATION_STATUS_CANCELLING:
 | |
|     case MIGRATION_STATUS_ACTIVE:
 | |
|     case MIGRATION_STATUS_POSTCOPY_ACTIVE:
 | |
|     case MIGRATION_STATUS_COLO:
 | |
|     case MIGRATION_STATUS_PRE_SWITCHOVER:
 | |
|     case MIGRATION_STATUS_DEVICE:
 | |
|     case MIGRATION_STATUS_WAIT_UNPLUG:
 | |
|         return false;
 | |
|     case MIGRATION_STATUS__MAX:
 | |
|         g_assert_not_reached();
 | |
|     }
 | |
| 
 | |
|     return false;
 | |
| }
 | |
| 
 | |
| bool migration_is_active(MigrationState *s)
 | |
| {
 | |
|     return (s->state == MIGRATION_STATUS_ACTIVE ||
 | |
|             s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE);
 | |
| }
 | |
| 
 | |
| bool migrate_mode_is_cpr(MigrationState *s)
 | |
| {
 | |
|     return s->parameters.mode == MIG_MODE_CPR_REBOOT;
 | |
| }
 | |
| 
 | |
| int migrate_init(MigrationState *s, Error **errp)
 | |
| {
 | |
|     int ret;
 | |
| 
 | |
|     ret = qemu_savevm_state_prepare(errp);
 | |
|     if (ret) {
 | |
|         return ret;
 | |
|     }
 | |
| 
 | |
|     /*
 | |
|      * Reinitialise all migration state, except
 | |
|      * parameters/capabilities that the user set, and
 | |
|      * locks.
 | |
|      */
 | |
|     s->to_dst_file = NULL;
 | |
|     s->state = MIGRATION_STATUS_NONE;
 | |
|     s->rp_state.from_dst_file = NULL;
 | |
|     s->mbps = 0.0;
 | |
|     s->pages_per_second = 0.0;
 | |
|     s->downtime = 0;
 | |
|     s->expected_downtime = 0;
 | |
|     s->setup_time = 0;
 | |
|     s->start_postcopy = false;
 | |
|     s->migration_thread_running = false;
 | |
|     error_free(s->error);
 | |
|     s->error = NULL;
 | |
|     s->vmdesc = NULL;
 | |
| 
 | |
|     migrate_set_state(&s->state, MIGRATION_STATUS_NONE, MIGRATION_STATUS_SETUP);
 | |
| 
 | |
|     s->start_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
 | |
|     s->total_time = 0;
 | |
|     s->vm_old_state = -1;
 | |
|     s->iteration_initial_bytes = 0;
 | |
|     s->threshold_size = 0;
 | |
|     s->switchover_acked = false;
 | |
|     s->rdma_migration = false;
 | |
|     /*
 | |
|      * set mig_stats memory to zero for a new migration
 | |
|      */
 | |
|     memset(&mig_stats, 0, sizeof(mig_stats));
 | |
|     migration_reset_vfio_bytes_transferred();
 | |
| 
 | |
|     return 0;
 | |
| }
 | |
| 
 | |
| static bool is_busy(Error **reasonp, Error **errp)
 | |
| {
 | |
|     ERRP_GUARD();
 | |
| 
 | |
|     /* Snapshots are similar to migrations, so check RUN_STATE_SAVE_VM too. */
 | |
|     if (runstate_check(RUN_STATE_SAVE_VM) || !migration_is_idle()) {
 | |
|         error_propagate_prepend(errp, *reasonp,
 | |
|                                 "disallowing migration blocker "
 | |
|                                 "(migration/snapshot in progress) for: ");
 | |
|         *reasonp = NULL;
 | |
|         return true;
 | |
|     }
 | |
|     return false;
 | |
| }
 | |
| 
 | |
| static bool is_only_migratable(Error **reasonp, Error **errp, int modes)
 | |
| {
 | |
|     ERRP_GUARD();
 | |
| 
 | |
|     if (only_migratable && (modes & BIT(MIG_MODE_NORMAL))) {
 | |
|         error_propagate_prepend(errp, *reasonp,
 | |
|                                 "disallowing migration blocker "
 | |
|                                 "(--only-migratable) for: ");
 | |
|         *reasonp = NULL;
 | |
|         return true;
 | |
|     }
 | |
|     return false;
 | |
| }
 | |
| 
 | |
| static int get_modes(MigMode mode, va_list ap)
 | |
| {
 | |
|     int modes = 0;
 | |
| 
 | |
|     while (mode != -1 && mode != MIG_MODE_ALL) {
 | |
|         assert(mode >= MIG_MODE_NORMAL && mode < MIG_MODE__MAX);
 | |
|         modes |= BIT(mode);
 | |
|         mode = va_arg(ap, MigMode);
 | |
|     }
 | |
|     if (mode == MIG_MODE_ALL) {
 | |
|         modes = BIT(MIG_MODE__MAX) - 1;
 | |
|     }
 | |
|     return modes;
 | |
| }
 | |
| 
 | |
| static int add_blockers(Error **reasonp, Error **errp, int modes)
 | |
| {
 | |
|     for (MigMode mode = 0; mode < MIG_MODE__MAX; mode++) {
 | |
|         if (modes & BIT(mode)) {
 | |
|             migration_blockers[mode] = g_slist_prepend(migration_blockers[mode],
 | |
|                                                        *reasonp);
 | |
|         }
 | |
|     }
 | |
|     return 0;
 | |
| }
 | |
| 
 | |
| int migrate_add_blocker(Error **reasonp, Error **errp)
 | |
| {
 | |
|     return migrate_add_blocker_modes(reasonp, errp, MIG_MODE_ALL);
 | |
| }
 | |
| 
 | |
| int migrate_add_blocker_normal(Error **reasonp, Error **errp)
 | |
| {
 | |
|     return migrate_add_blocker_modes(reasonp, errp, MIG_MODE_NORMAL, -1);
 | |
| }
 | |
| 
 | |
| int migrate_add_blocker_modes(Error **reasonp, Error **errp, MigMode mode, ...)
 | |
| {
 | |
|     int modes;
 | |
|     va_list ap;
 | |
| 
 | |
|     va_start(ap, mode);
 | |
|     modes = get_modes(mode, ap);
 | |
|     va_end(ap);
 | |
| 
 | |
|     if (is_only_migratable(reasonp, errp, modes)) {
 | |
|         return -EACCES;
 | |
|     } else if (is_busy(reasonp, errp)) {
 | |
|         return -EBUSY;
 | |
|     }
 | |
|     return add_blockers(reasonp, errp, modes);
 | |
| }
 | |
| 
 | |
| int migrate_add_blocker_internal(Error **reasonp, Error **errp)
 | |
| {
 | |
|     int modes = BIT(MIG_MODE__MAX) - 1;
 | |
| 
 | |
|     if (is_busy(reasonp, errp)) {
 | |
|         return -EBUSY;
 | |
|     }
 | |
|     return add_blockers(reasonp, errp, modes);
 | |
| }
 | |
| 
 | |
| void migrate_del_blocker(Error **reasonp)
 | |
| {
 | |
|     if (*reasonp) {
 | |
|         for (MigMode mode = 0; mode < MIG_MODE__MAX; mode++) {
 | |
|             migration_blockers[mode] = g_slist_remove(migration_blockers[mode],
 | |
|                                                       *reasonp);
 | |
|         }
 | |
|         error_free(*reasonp);
 | |
|         *reasonp = NULL;
 | |
|     }
 | |
| }
 | |
| 
 | |
| void qmp_migrate_incoming(const char *uri, bool has_channels,
 | |
|                           MigrationChannelList *channels, Error **errp)
 | |
| {
 | |
|     Error *local_err = NULL;
 | |
|     static bool once = true;
 | |
| 
 | |
|     if (!once) {
 | |
|         error_setg(errp, "The incoming migration has already been started");
 | |
|         return;
 | |
|     }
 | |
|     if (!runstate_check(RUN_STATE_INMIGRATE)) {
 | |
|         error_setg(errp, "'-incoming' was not specified on the command line");
 | |
|         return;
 | |
|     }
 | |
| 
 | |
|     if (!yank_register_instance(MIGRATION_YANK_INSTANCE, errp)) {
 | |
|         return;
 | |
|     }
 | |
| 
 | |
|     qemu_start_incoming_migration(uri, has_channels, channels, &local_err);
 | |
| 
 | |
|     if (local_err) {
 | |
|         yank_unregister_instance(MIGRATION_YANK_INSTANCE);
 | |
|         error_propagate(errp, local_err);
 | |
|         return;
 | |
|     }
 | |
| 
 | |
|     once = false;
 | |
| }
 | |
| 
 | |
| void qmp_migrate_recover(const char *uri, Error **errp)
 | |
| {
 | |
|     MigrationIncomingState *mis = migration_incoming_get_current();
 | |
| 
 | |
|     /*
 | |
|      * Don't even bother to use ERRP_GUARD() as it _must_ always be set by
 | |
|      * callers (no one should ignore a recover failure); if there is, it's a
 | |
|      * programming error.
 | |
|      */
 | |
|     assert(errp);
 | |
| 
 | |
|     if (mis->state != MIGRATION_STATUS_POSTCOPY_PAUSED) {
 | |
|         error_setg(errp, "Migrate recover can only be run "
 | |
|                    "when postcopy is paused.");
 | |
|         return;
 | |
|     }
 | |
| 
 | |
|     /* If there's an existing transport, release it */
 | |
|     migration_incoming_transport_cleanup(mis);
 | |
| 
 | |
|     /*
 | |
|      * Note that this call will never start a real migration; it will
 | |
|      * only re-setup the migration stream and poke existing migration
 | |
|      * to continue using that newly established channel.
 | |
|      */
 | |
|     qemu_start_incoming_migration(uri, false, NULL, errp);
 | |
| }
 | |
| 
 | |
| void qmp_migrate_pause(Error **errp)
 | |
| {
 | |
|     MigrationState *ms = migrate_get_current();
 | |
|     MigrationIncomingState *mis = migration_incoming_get_current();
 | |
|     int ret = 0;
 | |
| 
 | |
|     if (migration_postcopy_is_alive(ms->state)) {
 | |
|         /* Source side, during postcopy */
 | |
|         Error *error = NULL;
 | |
| 
 | |
|         /* Tell the core migration that we're pausing */
 | |
|         error_setg(&error, "Postcopy migration is paused by the user");
 | |
|         migrate_set_error(ms, error);
 | |
|         error_free(error);
 | |
| 
 | |
|         qemu_mutex_lock(&ms->qemu_file_lock);
 | |
|         if (ms->to_dst_file) {
 | |
|             ret = qemu_file_shutdown(ms->to_dst_file);
 | |
|         }
 | |
|         qemu_mutex_unlock(&ms->qemu_file_lock);
 | |
|         if (ret) {
 | |
|             error_setg(errp, "Failed to pause source migration");
 | |
|         }
 | |
| 
 | |
|         /*
 | |
|          * Kick the migration thread out of any waiting windows (on behalf
 | |
|          * of the rp thread).
 | |
|          */
 | |
|         migration_rp_kick(ms);
 | |
| 
 | |
|         return;
 | |
|     }
 | |
| 
 | |
|     if (migration_postcopy_is_alive(mis->state)) {
 | |
|         ret = qemu_file_shutdown(mis->from_src_file);
 | |
|         if (ret) {
 | |
|             error_setg(errp, "Failed to pause destination migration");
 | |
|         }
 | |
|         return;
 | |
|     }
 | |
| 
 | |
|     error_setg(errp, "migrate-pause is currently only supported "
 | |
|                "during postcopy-active or postcopy-recover state");
 | |
| }
 | |
| 
 | |
| bool migration_is_blocked(Error **errp)
 | |
| {
 | |
|     GSList *blockers = migration_blockers[migrate_mode()];
 | |
| 
 | |
|     if (qemu_savevm_state_blocked(errp)) {
 | |
|         return true;
 | |
|     }
 | |
| 
 | |
|     if (blockers) {
 | |
|         error_propagate(errp, error_copy(blockers->data));
 | |
|         return true;
 | |
|     }
 | |
| 
 | |
|     return false;
 | |
| }
 | |
| 
 | |
| /* Returns true if continue to migrate, or false if error detected */
 | |
| static bool migrate_prepare(MigrationState *s, bool blk, bool blk_inc,
 | |
|                             bool resume, Error **errp)
 | |
| {
 | |
|     if (blk_inc) {
 | |
|         warn_report("parameter 'inc' is deprecated;"
 | |
|                     " use blockdev-mirror with NBD instead");
 | |
|     }
 | |
| 
 | |
|     if (blk) {
 | |
|         warn_report("parameter 'blk' is deprecated;"
 | |
|                     " use blockdev-mirror with NBD instead");
 | |
|     }
 | |
| 
 | |
|     if (resume) {
 | |
|         if (s->state != MIGRATION_STATUS_POSTCOPY_PAUSED) {
 | |
|             error_setg(errp, "Cannot resume if there is no "
 | |
|                        "paused migration");
 | |
|             return false;
 | |
|         }
 | |
| 
 | |
|         /*
 | |
|          * Postcopy recovery won't work well with release-ram
 | |
|          * capability since release-ram will drop the page buffer as
 | |
|          * long as the page is put into the send buffer.  So if there
 | |
|          * is a network failure happened, any page buffers that have
 | |
|          * not yet reached the destination VM but have already been
 | |
|          * sent from the source VM will be lost forever.  Let's refuse
 | |
|          * the client from resuming such a postcopy migration.
 | |
|          * Luckily release-ram was designed to only be used when src
 | |
|          * and destination VMs are on the same host, so it should be
 | |
|          * fine.
 | |
|          */
 | |
|         if (migrate_release_ram()) {
 | |
|             error_setg(errp, "Postcopy recovery cannot work "
 | |
|                        "when release-ram capability is set");
 | |
|             return false;
 | |
|         }
 | |
| 
 | |
|         /* This is a resume, skip init status */
 | |
|         return true;
 | |
|     }
 | |
| 
 | |
|     if (migration_is_running(s->state)) {
 | |
|         error_setg(errp, QERR_MIGRATION_ACTIVE);
 | |
|         return false;
 | |
|     }
 | |
| 
 | |
|     if (runstate_check(RUN_STATE_INMIGRATE)) {
 | |
|         error_setg(errp, "Guest is waiting for an incoming migration");
 | |
|         return false;
 | |
|     }
 | |
| 
 | |
|     if (runstate_check(RUN_STATE_POSTMIGRATE)) {
 | |
|         error_setg(errp, "Can't migrate the vm that was paused due to "
 | |
|                    "previous migration");
 | |
|         return false;
 | |
|     }
 | |
| 
 | |
|     if (kvm_hwpoisoned_mem()) {
 | |
|         error_setg(errp, "Can't migrate this vm with hardware poisoned memory, "
 | |
|                    "please reboot the vm and try again");
 | |
|         return false;
 | |
|     }
 | |
| 
 | |
|     if (migration_is_blocked(errp)) {
 | |
|         return false;
 | |
|     }
 | |
| 
 | |
|     if (migrate_mapped_ram()) {
 | |
|         if (migrate_tls()) {
 | |
|             error_setg(errp, "Cannot use TLS with mapped-ram");
 | |
|             return false;
 | |
|         }
 | |
| 
 | |
|         if (migrate_multifd_compression()) {
 | |
|             error_setg(errp, "Cannot use compression with mapped-ram");
 | |
|             return false;
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     if (migrate_mode_is_cpr(s)) {
 | |
|         const char *conflict = NULL;
 | |
| 
 | |
|         if (migrate_postcopy()) {
 | |
|             conflict = "postcopy";
 | |
|         } else if (migrate_background_snapshot()) {
 | |
|             conflict = "background snapshot";
 | |
|         } else if (migrate_colo()) {
 | |
|             conflict = "COLO";
 | |
|         }
 | |
| 
 | |
|         if (conflict) {
 | |
|             error_setg(errp, "Cannot use %s with CPR", conflict);
 | |
|             return false;
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     if (blk || blk_inc) {
 | |
|         if (migrate_colo()) {
 | |
|             error_setg(errp, "No disk migration is required in COLO mode");
 | |
|             return false;
 | |
|         }
 | |
|         if (migrate_block() || migrate_block_incremental()) {
 | |
|             error_setg(errp, "Command options are incompatible with "
 | |
|                        "current migration capabilities");
 | |
|             return false;
 | |
|         }
 | |
|         if (!migrate_cap_set(MIGRATION_CAPABILITY_BLOCK, true, errp)) {
 | |
|             return false;
 | |
|         }
 | |
|         s->must_remove_block_options = true;
 | |
|     }
 | |
| 
 | |
|     if (blk_inc) {
 | |
|         migrate_set_block_incremental(true);
 | |
|     }
 | |
| 
 | |
|     if (migrate_init(s, errp)) {
 | |
|         return false;
 | |
|     }
 | |
| 
 | |
|     return true;
 | |
| }
 | |
| 
 | |
| void qmp_migrate(const char *uri, bool has_channels,
 | |
|                  MigrationChannelList *channels, bool has_blk, bool blk,
 | |
|                  bool has_inc, bool inc, bool has_detach, bool detach,
 | |
|                  bool has_resume, bool resume, Error **errp)
 | |
| {
 | |
|     bool resume_requested;
 | |
|     Error *local_err = NULL;
 | |
|     MigrationState *s = migrate_get_current();
 | |
|     g_autoptr(MigrationChannel) channel = NULL;
 | |
|     MigrationAddress *addr = NULL;
 | |
| 
 | |
|     /*
 | |
|      * Having preliminary checks for uri and channel
 | |
|      */
 | |
|     if (!uri == !channels) {
 | |
|         error_setg(errp, "need either 'uri' or 'channels' argument");
 | |
|         return;
 | |
|     }
 | |
| 
 | |
|     if (channels) {
 | |
|         /* To verify that Migrate channel list has only item */
 | |
|         if (channels->next) {
 | |
|             error_setg(errp, "Channel list has more than one entries");
 | |
|             return;
 | |
|         }
 | |
|         addr = channels->value->addr;
 | |
|     }
 | |
| 
 | |
|     if (uri) {
 | |
|         /* caller uses the old URI syntax */
 | |
|         if (!migrate_uri_parse(uri, &channel, errp)) {
 | |
|             return;
 | |
|         }
 | |
|         addr = channel->addr;
 | |
|     }
 | |
| 
 | |
|     /* transport mechanism not suitable for migration? */
 | |
|     if (!migration_channels_and_transport_compatible(addr, errp)) {
 | |
|         return;
 | |
|     }
 | |
| 
 | |
|     resume_requested = has_resume && resume;
 | |
|     if (!migrate_prepare(s, has_blk && blk, has_inc && inc,
 | |
|                          resume_requested, errp)) {
 | |
|         /* Error detected, put into errp */
 | |
|         return;
 | |
|     }
 | |
| 
 | |
|     if (!resume_requested) {
 | |
|         if (!yank_register_instance(MIGRATION_YANK_INSTANCE, errp)) {
 | |
|             return;
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     if (addr->transport == MIGRATION_ADDRESS_TYPE_SOCKET) {
 | |
|         SocketAddress *saddr = &addr->u.socket;
 | |
|         if (saddr->type == SOCKET_ADDRESS_TYPE_INET ||
 | |
|             saddr->type == SOCKET_ADDRESS_TYPE_UNIX ||
 | |
|             saddr->type == SOCKET_ADDRESS_TYPE_VSOCK) {
 | |
|             socket_start_outgoing_migration(s, saddr, &local_err);
 | |
|         } else if (saddr->type == SOCKET_ADDRESS_TYPE_FD) {
 | |
|             fd_start_outgoing_migration(s, saddr->u.fd.str, &local_err);
 | |
|         }
 | |
| #ifdef CONFIG_RDMA
 | |
|     } else if (addr->transport == MIGRATION_ADDRESS_TYPE_RDMA) {
 | |
|         rdma_start_outgoing_migration(s, &addr->u.rdma, &local_err);
 | |
| #endif
 | |
|     } else if (addr->transport == MIGRATION_ADDRESS_TYPE_EXEC) {
 | |
|         exec_start_outgoing_migration(s, addr->u.exec.args, &local_err);
 | |
|     } else if (addr->transport == MIGRATION_ADDRESS_TYPE_FILE) {
 | |
|         file_start_outgoing_migration(s, &addr->u.file, &local_err);
 | |
|     } else {
 | |
|         error_setg(&local_err, QERR_INVALID_PARAMETER_VALUE, "uri",
 | |
|                    "a valid migration protocol");
 | |
|         migrate_set_state(&s->state, MIGRATION_STATUS_SETUP,
 | |
|                           MIGRATION_STATUS_FAILED);
 | |
|         block_cleanup_parameters();
 | |
|     }
 | |
| 
 | |
|     if (local_err) {
 | |
|         if (!resume_requested) {
 | |
|             yank_unregister_instance(MIGRATION_YANK_INSTANCE);
 | |
|         }
 | |
|         migrate_fd_error(s, local_err);
 | |
|         error_propagate(errp, local_err);
 | |
|         return;
 | |
|     }
 | |
| }
 | |
| 
 | |
| void qmp_migrate_cancel(Error **errp)
 | |
| {
 | |
|     migration_cancel(NULL);
 | |
| }
 | |
| 
 | |
| void qmp_migrate_continue(MigrationStatus state, Error **errp)
 | |
| {
 | |
|     MigrationState *s = migrate_get_current();
 | |
|     if (s->state != state) {
 | |
|         error_setg(errp,  "Migration not in expected state: %s",
 | |
|                    MigrationStatus_str(s->state));
 | |
|         return;
 | |
|     }
 | |
|     qemu_sem_post(&s->pause_sem);
 | |
| }
 | |
| 
 | |
| int migration_rp_wait(MigrationState *s)
 | |
| {
 | |
|     /* If migration has failure already, ignore the wait */
 | |
|     if (migrate_has_error(s)) {
 | |
|         return -1;
 | |
|     }
 | |
| 
 | |
|     qemu_sem_wait(&s->rp_state.rp_sem);
 | |
| 
 | |
|     /* After wait, double check that there's no failure */
 | |
|     if (migrate_has_error(s)) {
 | |
|         return -1;
 | |
|     }
 | |
| 
 | |
|     return 0;
 | |
| }
 | |
| 
 | |
| void migration_rp_kick(MigrationState *s)
 | |
| {
 | |
|     qemu_sem_post(&s->rp_state.rp_sem);
 | |
| }
 | |
| 
 | |
| static struct rp_cmd_args {
 | |
|     ssize_t     len; /* -1 = variable */
 | |
|     const char *name;
 | |
| } rp_cmd_args[] = {
 | |
|     [MIG_RP_MSG_INVALID]        = { .len = -1, .name = "INVALID" },
 | |
|     [MIG_RP_MSG_SHUT]           = { .len =  4, .name = "SHUT" },
 | |
|     [MIG_RP_MSG_PONG]           = { .len =  4, .name = "PONG" },
 | |
|     [MIG_RP_MSG_REQ_PAGES]      = { .len = 12, .name = "REQ_PAGES" },
 | |
|     [MIG_RP_MSG_REQ_PAGES_ID]   = { .len = -1, .name = "REQ_PAGES_ID" },
 | |
|     [MIG_RP_MSG_RECV_BITMAP]    = { .len = -1, .name = "RECV_BITMAP" },
 | |
|     [MIG_RP_MSG_RESUME_ACK]     = { .len =  4, .name = "RESUME_ACK" },
 | |
|     [MIG_RP_MSG_SWITCHOVER_ACK] = { .len =  0, .name = "SWITCHOVER_ACK" },
 | |
|     [MIG_RP_MSG_MAX]            = { .len = -1, .name = "MAX" },
 | |
| };
 | |
| 
 | |
| /*
 | |
|  * Process a request for pages received on the return path,
 | |
|  * We're allowed to send more than requested (e.g. to round to our page size)
 | |
|  * and we don't need to send pages that have already been sent.
 | |
|  */
 | |
| static void
 | |
| migrate_handle_rp_req_pages(MigrationState *ms, const char* rbname,
 | |
|                             ram_addr_t start, size_t len, Error **errp)
 | |
| {
 | |
|     long our_host_ps = qemu_real_host_page_size();
 | |
| 
 | |
|     trace_migrate_handle_rp_req_pages(rbname, start, len);
 | |
| 
 | |
|     /*
 | |
|      * Since we currently insist on matching page sizes, just sanity check
 | |
|      * we're being asked for whole host pages.
 | |
|      */
 | |
|     if (!QEMU_IS_ALIGNED(start, our_host_ps) ||
 | |
|         !QEMU_IS_ALIGNED(len, our_host_ps)) {
 | |
|         error_setg(errp, "MIG_RP_MSG_REQ_PAGES: Misaligned page request, start:"
 | |
|                    RAM_ADDR_FMT " len: %zd", start, len);
 | |
|         return;
 | |
|     }
 | |
| 
 | |
|     ram_save_queue_pages(rbname, start, len, errp);
 | |
| }
 | |
| 
 | |
| static bool migrate_handle_rp_recv_bitmap(MigrationState *s, char *block_name,
 | |
|                                           Error **errp)
 | |
| {
 | |
|     RAMBlock *block = qemu_ram_block_by_name(block_name);
 | |
| 
 | |
|     if (!block) {
 | |
|         error_setg(errp, "MIG_RP_MSG_RECV_BITMAP has invalid block name '%s'",
 | |
|                    block_name);
 | |
|         return false;
 | |
|     }
 | |
| 
 | |
|     /* Fetch the received bitmap and refresh the dirty bitmap */
 | |
|     return ram_dirty_bitmap_reload(s, block, errp);
 | |
| }
 | |
| 
 | |
| static bool migrate_handle_rp_resume_ack(MigrationState *s,
 | |
|                                          uint32_t value, Error **errp)
 | |
| {
 | |
|     trace_source_return_path_thread_resume_ack(value);
 | |
| 
 | |
|     if (value != MIGRATION_RESUME_ACK_VALUE) {
 | |
|         error_setg(errp, "illegal resume_ack value %"PRIu32, value);
 | |
|         return false;
 | |
|     }
 | |
| 
 | |
|     /* Now both sides are active. */
 | |
|     migrate_set_state(&s->state, MIGRATION_STATUS_POSTCOPY_RECOVER,
 | |
|                       MIGRATION_STATUS_POSTCOPY_ACTIVE);
 | |
| 
 | |
|     /* Notify send thread that time to continue send pages */
 | |
|     migration_rp_kick(s);
 | |
| 
 | |
|     return true;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Release ms->rp_state.from_dst_file (and postcopy_qemufile_src if
 | |
|  * existed) in a safe way.
 | |
|  */
 | |
| static void migration_release_dst_files(MigrationState *ms)
 | |
| {
 | |
|     QEMUFile *file;
 | |
| 
 | |
|     WITH_QEMU_LOCK_GUARD(&ms->qemu_file_lock) {
 | |
|         /*
 | |
|          * Reset the from_dst_file pointer first before releasing it, as we
 | |
|          * can't block within lock section
 | |
|          */
 | |
|         file = ms->rp_state.from_dst_file;
 | |
|         ms->rp_state.from_dst_file = NULL;
 | |
|     }
 | |
| 
 | |
|     /*
 | |
|      * Do the same to postcopy fast path socket too if there is.  No
 | |
|      * locking needed because this qemufile should only be managed by
 | |
|      * return path thread.
 | |
|      */
 | |
|     if (ms->postcopy_qemufile_src) {
 | |
|         migration_ioc_unregister_yank_from_file(ms->postcopy_qemufile_src);
 | |
|         qemu_file_shutdown(ms->postcopy_qemufile_src);
 | |
|         qemu_fclose(ms->postcopy_qemufile_src);
 | |
|         ms->postcopy_qemufile_src = NULL;
 | |
|     }
 | |
| 
 | |
|     qemu_fclose(file);
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Handles messages sent on the return path towards the source VM
 | |
|  *
 | |
|  */
 | |
| static void *source_return_path_thread(void *opaque)
 | |
| {
 | |
|     MigrationState *ms = opaque;
 | |
|     QEMUFile *rp = ms->rp_state.from_dst_file;
 | |
|     uint16_t header_len, header_type;
 | |
|     uint8_t buf[512];
 | |
|     uint32_t tmp32, sibling_error;
 | |
|     ram_addr_t start = 0; /* =0 to silence warning */
 | |
|     size_t  len = 0, expected_len;
 | |
|     Error *err = NULL;
 | |
|     int res;
 | |
| 
 | |
|     trace_source_return_path_thread_entry();
 | |
|     rcu_register_thread();
 | |
| 
 | |
|     while (migration_is_setup_or_active(ms->state)) {
 | |
|         trace_source_return_path_thread_loop_top();
 | |
| 
 | |
|         header_type = qemu_get_be16(rp);
 | |
|         header_len = qemu_get_be16(rp);
 | |
| 
 | |
|         if (qemu_file_get_error(rp)) {
 | |
|             qemu_file_get_error_obj(rp, &err);
 | |
|             goto out;
 | |
|         }
 | |
| 
 | |
|         if (header_type >= MIG_RP_MSG_MAX ||
 | |
|             header_type == MIG_RP_MSG_INVALID) {
 | |
|             error_setg(&err, "Received invalid message 0x%04x length 0x%04x",
 | |
|                        header_type, header_len);
 | |
|             goto out;
 | |
|         }
 | |
| 
 | |
|         if ((rp_cmd_args[header_type].len != -1 &&
 | |
|             header_len != rp_cmd_args[header_type].len) ||
 | |
|             header_len > sizeof(buf)) {
 | |
|             error_setg(&err, "Received '%s' message (0x%04x) with"
 | |
|                        "incorrect length %d expecting %zu",
 | |
|                        rp_cmd_args[header_type].name, header_type, header_len,
 | |
|                        (size_t)rp_cmd_args[header_type].len);
 | |
|             goto out;
 | |
|         }
 | |
| 
 | |
|         /* We know we've got a valid header by this point */
 | |
|         res = qemu_get_buffer(rp, buf, header_len);
 | |
|         if (res != header_len) {
 | |
|             error_setg(&err, "Failed reading data for message 0x%04x"
 | |
|                        " read %d expected %d",
 | |
|                        header_type, res, header_len);
 | |
|             goto out;
 | |
|         }
 | |
| 
 | |
|         /* OK, we have the message and the data */
 | |
|         switch (header_type) {
 | |
|         case MIG_RP_MSG_SHUT:
 | |
|             sibling_error = ldl_be_p(buf);
 | |
|             trace_source_return_path_thread_shut(sibling_error);
 | |
|             if (sibling_error) {
 | |
|                 error_setg(&err, "Sibling indicated error %d", sibling_error);
 | |
|             }
 | |
|             /*
 | |
|              * We'll let the main thread deal with closing the RP
 | |
|              * we could do a shutdown(2) on it, but we're the only user
 | |
|              * anyway, so there's nothing gained.
 | |
|              */
 | |
|             goto out;
 | |
| 
 | |
|         case MIG_RP_MSG_PONG:
 | |
|             tmp32 = ldl_be_p(buf);
 | |
|             trace_source_return_path_thread_pong(tmp32);
 | |
|             qemu_sem_post(&ms->rp_state.rp_pong_acks);
 | |
|             break;
 | |
| 
 | |
|         case MIG_RP_MSG_REQ_PAGES:
 | |
|             start = ldq_be_p(buf);
 | |
|             len = ldl_be_p(buf + 8);
 | |
|             migrate_handle_rp_req_pages(ms, NULL, start, len, &err);
 | |
|             if (err) {
 | |
|                 goto out;
 | |
|             }
 | |
|             break;
 | |
| 
 | |
|         case MIG_RP_MSG_REQ_PAGES_ID:
 | |
|             expected_len = 12 + 1; /* header + termination */
 | |
| 
 | |
|             if (header_len >= expected_len) {
 | |
|                 start = ldq_be_p(buf);
 | |
|                 len = ldl_be_p(buf + 8);
 | |
|                 /* Now we expect an idstr */
 | |
|                 tmp32 = buf[12]; /* Length of the following idstr */
 | |
|                 buf[13 + tmp32] = '\0';
 | |
|                 expected_len += tmp32;
 | |
|             }
 | |
|             if (header_len != expected_len) {
 | |
|                 error_setg(&err, "Req_Page_id with length %d expecting %zd",
 | |
|                            header_len, expected_len);
 | |
|                 goto out;
 | |
|             }
 | |
|             migrate_handle_rp_req_pages(ms, (char *)&buf[13], start, len,
 | |
|                                         &err);
 | |
|             if (err) {
 | |
|                 goto out;
 | |
|             }
 | |
|             break;
 | |
| 
 | |
|         case MIG_RP_MSG_RECV_BITMAP:
 | |
|             if (header_len < 1) {
 | |
|                 error_setg(&err, "MIG_RP_MSG_RECV_BITMAP missing block name");
 | |
|                 goto out;
 | |
|             }
 | |
|             /* Format: len (1B) + idstr (<255B). This ends the idstr. */
 | |
|             buf[buf[0] + 1] = '\0';
 | |
|             if (!migrate_handle_rp_recv_bitmap(ms, (char *)(buf + 1), &err)) {
 | |
|                 goto out;
 | |
|             }
 | |
|             break;
 | |
| 
 | |
|         case MIG_RP_MSG_RESUME_ACK:
 | |
|             tmp32 = ldl_be_p(buf);
 | |
|             if (!migrate_handle_rp_resume_ack(ms, tmp32, &err)) {
 | |
|                 goto out;
 | |
|             }
 | |
|             break;
 | |
| 
 | |
|         case MIG_RP_MSG_SWITCHOVER_ACK:
 | |
|             ms->switchover_acked = true;
 | |
|             trace_source_return_path_thread_switchover_acked();
 | |
|             break;
 | |
| 
 | |
|         default:
 | |
|             break;
 | |
|         }
 | |
|     }
 | |
| 
 | |
| out:
 | |
|     if (err) {
 | |
|         migrate_set_error(ms, err);
 | |
|         error_free(err);
 | |
|         trace_source_return_path_thread_bad_end();
 | |
|     }
 | |
| 
 | |
|     if (ms->state == MIGRATION_STATUS_POSTCOPY_RECOVER) {
 | |
|         /*
 | |
|          * this will be extremely unlikely: that we got yet another network
 | |
|          * issue during recovering of the 1st network failure.. during this
 | |
|          * period the main migration thread can be waiting on rp_sem for
 | |
|          * this thread to sync with the other side.
 | |
|          *
 | |
|          * When this happens, explicitly kick the migration thread out of
 | |
|          * RECOVER stage and back to PAUSED, so the admin can try
 | |
|          * everything again.
 | |
|          */
 | |
|         migration_rp_kick(ms);
 | |
|     }
 | |
| 
 | |
|     trace_source_return_path_thread_end();
 | |
|     rcu_unregister_thread();
 | |
| 
 | |
|     return NULL;
 | |
| }
 | |
| 
 | |
| static int open_return_path_on_source(MigrationState *ms)
 | |
| {
 | |
|     ms->rp_state.from_dst_file = qemu_file_get_return_path(ms->to_dst_file);
 | |
|     if (!ms->rp_state.from_dst_file) {
 | |
|         return -1;
 | |
|     }
 | |
| 
 | |
|     trace_open_return_path_on_source();
 | |
| 
 | |
|     qemu_thread_create(&ms->rp_state.rp_thread, "return path",
 | |
|                        source_return_path_thread, ms, QEMU_THREAD_JOINABLE);
 | |
|     ms->rp_state.rp_thread_created = true;
 | |
| 
 | |
|     trace_open_return_path_on_source_continue();
 | |
| 
 | |
|     return 0;
 | |
| }
 | |
| 
 | |
| /* Return true if error detected, or false otherwise */
 | |
| static bool close_return_path_on_source(MigrationState *ms)
 | |
| {
 | |
|     if (!ms->rp_state.rp_thread_created) {
 | |
|         return false;
 | |
|     }
 | |
| 
 | |
|     trace_migration_return_path_end_before();
 | |
| 
 | |
|     /*
 | |
|      * If this is a normal exit then the destination will send a SHUT
 | |
|      * and the rp_thread will exit, however if there's an error we
 | |
|      * need to cause it to exit. shutdown(2), if we have it, will
 | |
|      * cause it to unblock if it's stuck waiting for the destination.
 | |
|      */
 | |
|     WITH_QEMU_LOCK_GUARD(&ms->qemu_file_lock) {
 | |
|         if (migrate_has_error(ms) && ms->rp_state.from_dst_file) {
 | |
|             qemu_file_shutdown(ms->rp_state.from_dst_file);
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     qemu_thread_join(&ms->rp_state.rp_thread);
 | |
|     ms->rp_state.rp_thread_created = false;
 | |
|     migration_release_dst_files(ms);
 | |
|     trace_migration_return_path_end_after();
 | |
| 
 | |
|     /* Return path will persist the error in MigrationState when quit */
 | |
|     return migrate_has_error(ms);
 | |
| }
 | |
| 
 | |
| static inline void
 | |
| migration_wait_main_channel(MigrationState *ms)
 | |
| {
 | |
|     /* Wait until one PONG message received */
 | |
|     qemu_sem_wait(&ms->rp_state.rp_pong_acks);
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Switch from normal iteration to postcopy
 | |
|  * Returns non-0 on error
 | |
|  */
 | |
| static int postcopy_start(MigrationState *ms, Error **errp)
 | |
| {
 | |
|     int ret;
 | |
|     QIOChannelBuffer *bioc;
 | |
|     QEMUFile *fb;
 | |
|     uint64_t bandwidth = migrate_max_postcopy_bandwidth();
 | |
|     bool restart_block = false;
 | |
|     int cur_state = MIGRATION_STATUS_ACTIVE;
 | |
| 
 | |
|     if (migrate_postcopy_preempt()) {
 | |
|         migration_wait_main_channel(ms);
 | |
|         if (postcopy_preempt_establish_channel(ms)) {
 | |
|             migrate_set_state(&ms->state, ms->state, MIGRATION_STATUS_FAILED);
 | |
|             return -1;
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     if (!migrate_pause_before_switchover()) {
 | |
|         migrate_set_state(&ms->state, MIGRATION_STATUS_ACTIVE,
 | |
|                           MIGRATION_STATUS_POSTCOPY_ACTIVE);
 | |
|     }
 | |
| 
 | |
|     trace_postcopy_start();
 | |
|     bql_lock();
 | |
|     trace_postcopy_start_set_run();
 | |
| 
 | |
|     ret = migration_stop_vm(ms, RUN_STATE_FINISH_MIGRATE);
 | |
|     if (ret < 0) {
 | |
|         goto fail;
 | |
|     }
 | |
| 
 | |
|     ret = migration_maybe_pause(ms, &cur_state,
 | |
|                                 MIGRATION_STATUS_POSTCOPY_ACTIVE);
 | |
|     if (ret < 0) {
 | |
|         goto fail;
 | |
|     }
 | |
| 
 | |
|     ret = bdrv_inactivate_all();
 | |
|     if (ret < 0) {
 | |
|         goto fail;
 | |
|     }
 | |
|     restart_block = true;
 | |
| 
 | |
|     /*
 | |
|      * Cause any non-postcopiable, but iterative devices to
 | |
|      * send out their final data.
 | |
|      */
 | |
|     qemu_savevm_state_complete_precopy(ms->to_dst_file, true, false);
 | |
| 
 | |
|     /*
 | |
|      * in Finish migrate and with the io-lock held everything should
 | |
|      * be quiet, but we've potentially still got dirty pages and we
 | |
|      * need to tell the destination to throw any pages it's already received
 | |
|      * that are dirty
 | |
|      */
 | |
|     if (migrate_postcopy_ram()) {
 | |
|         ram_postcopy_send_discard_bitmap(ms);
 | |
|     }
 | |
| 
 | |
|     /*
 | |
|      * send rest of state - note things that are doing postcopy
 | |
|      * will notice we're in POSTCOPY_ACTIVE and not actually
 | |
|      * wrap their state up here
 | |
|      */
 | |
|     migration_rate_set(bandwidth);
 | |
|     if (migrate_postcopy_ram()) {
 | |
|         /* Ping just for debugging, helps line traces up */
 | |
|         qemu_savevm_send_ping(ms->to_dst_file, 2);
 | |
|     }
 | |
| 
 | |
|     /*
 | |
|      * While loading the device state we may trigger page transfer
 | |
|      * requests and the fd must be free to process those, and thus
 | |
|      * the destination must read the whole device state off the fd before
 | |
|      * it starts processing it.  Unfortunately the ad-hoc migration format
 | |
|      * doesn't allow the destination to know the size to read without fully
 | |
|      * parsing it through each devices load-state code (especially the open
 | |
|      * coded devices that use get/put).
 | |
|      * So we wrap the device state up in a package with a length at the start;
 | |
|      * to do this we use a qemu_buf to hold the whole of the device state.
 | |
|      */
 | |
|     bioc = qio_channel_buffer_new(4096);
 | |
|     qio_channel_set_name(QIO_CHANNEL(bioc), "migration-postcopy-buffer");
 | |
|     fb = qemu_file_new_output(QIO_CHANNEL(bioc));
 | |
|     object_unref(OBJECT(bioc));
 | |
| 
 | |
|     /*
 | |
|      * Make sure the receiver can get incoming pages before we send the rest
 | |
|      * of the state
 | |
|      */
 | |
|     qemu_savevm_send_postcopy_listen(fb);
 | |
| 
 | |
|     qemu_savevm_state_complete_precopy(fb, false, false);
 | |
|     if (migrate_postcopy_ram()) {
 | |
|         qemu_savevm_send_ping(fb, 3);
 | |
|     }
 | |
| 
 | |
|     qemu_savevm_send_postcopy_run(fb);
 | |
| 
 | |
|     /* <><> end of stuff going into the package */
 | |
| 
 | |
|     /* Last point of recovery; as soon as we send the package the destination
 | |
|      * can open devices and potentially start running.
 | |
|      * Lets just check again we've not got any errors.
 | |
|      */
 | |
|     ret = qemu_file_get_error(ms->to_dst_file);
 | |
|     if (ret) {
 | |
|         error_setg(errp, "postcopy_start: Migration stream errored (pre package)");
 | |
|         goto fail_closefb;
 | |
|     }
 | |
| 
 | |
|     restart_block = false;
 | |
| 
 | |
|     /* Now send that blob */
 | |
|     if (qemu_savevm_send_packaged(ms->to_dst_file, bioc->data, bioc->usage)) {
 | |
|         goto fail_closefb;
 | |
|     }
 | |
|     qemu_fclose(fb);
 | |
| 
 | |
|     /* Send a notify to give a chance for anything that needs to happen
 | |
|      * at the transition to postcopy and after the device state; in particular
 | |
|      * spice needs to trigger a transition now
 | |
|      */
 | |
|     migration_call_notifiers(ms, MIG_EVENT_PRECOPY_DONE, NULL);
 | |
| 
 | |
|     migration_downtime_end(ms);
 | |
| 
 | |
|     bql_unlock();
 | |
| 
 | |
|     if (migrate_postcopy_ram()) {
 | |
|         /*
 | |
|          * Although this ping is just for debug, it could potentially be
 | |
|          * used for getting a better measurement of downtime at the source.
 | |
|          */
 | |
|         qemu_savevm_send_ping(ms->to_dst_file, 4);
 | |
|     }
 | |
| 
 | |
|     if (migrate_release_ram()) {
 | |
|         ram_postcopy_migrated_memory_release(ms);
 | |
|     }
 | |
| 
 | |
|     ret = qemu_file_get_error(ms->to_dst_file);
 | |
|     if (ret) {
 | |
|         error_setg_errno(errp, -ret, "postcopy_start: Migration stream error");
 | |
|         bql_lock();
 | |
|         goto fail;
 | |
|     }
 | |
|     trace_postcopy_preempt_enabled(migrate_postcopy_preempt());
 | |
| 
 | |
|     return ret;
 | |
| 
 | |
| fail_closefb:
 | |
|     qemu_fclose(fb);
 | |
| fail:
 | |
|     migrate_set_state(&ms->state, MIGRATION_STATUS_POSTCOPY_ACTIVE,
 | |
|                           MIGRATION_STATUS_FAILED);
 | |
|     if (restart_block) {
 | |
|         /* A failure happened early enough that we know the destination hasn't
 | |
|          * accessed block devices, so we're safe to recover.
 | |
|          */
 | |
|         Error *local_err = NULL;
 | |
| 
 | |
|         bdrv_activate_all(&local_err);
 | |
|         if (local_err) {
 | |
|             error_report_err(local_err);
 | |
|         }
 | |
|     }
 | |
|     migration_call_notifiers(ms, MIG_EVENT_PRECOPY_FAILED, NULL);
 | |
|     bql_unlock();
 | |
|     return -1;
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * migration_maybe_pause: Pause if required to by
 | |
|  * migrate_pause_before_switchover called with the BQL locked
 | |
|  * Returns: 0 on success
 | |
|  */
 | |
| static int migration_maybe_pause(MigrationState *s,
 | |
|                                  int *current_active_state,
 | |
|                                  int new_state)
 | |
| {
 | |
|     if (!migrate_pause_before_switchover()) {
 | |
|         return 0;
 | |
|     }
 | |
| 
 | |
|     /* Since leaving this state is not atomic with posting the semaphore
 | |
|      * it's possible that someone could have issued multiple migrate_continue
 | |
|      * and the semaphore is incorrectly positive at this point;
 | |
|      * the docs say it's undefined to reinit a semaphore that's already
 | |
|      * init'd, so use timedwait to eat up any existing posts.
 | |
|      */
 | |
|     while (qemu_sem_timedwait(&s->pause_sem, 1) == 0) {
 | |
|         /* This block intentionally left blank */
 | |
|     }
 | |
| 
 | |
|     /*
 | |
|      * If the migration is cancelled when it is in the completion phase,
 | |
|      * the migration state is set to MIGRATION_STATUS_CANCELLING.
 | |
|      * So we don't need to wait a semaphore, otherwise we would always
 | |
|      * wait for the 'pause_sem' semaphore.
 | |
|      */
 | |
|     if (s->state != MIGRATION_STATUS_CANCELLING) {
 | |
|         bql_unlock();
 | |
|         migrate_set_state(&s->state, *current_active_state,
 | |
|                           MIGRATION_STATUS_PRE_SWITCHOVER);
 | |
|         qemu_sem_wait(&s->pause_sem);
 | |
|         migrate_set_state(&s->state, MIGRATION_STATUS_PRE_SWITCHOVER,
 | |
|                           new_state);
 | |
|         *current_active_state = new_state;
 | |
|         bql_lock();
 | |
|     }
 | |
| 
 | |
|     return s->state == new_state ? 0 : -EINVAL;
 | |
| }
 | |
| 
 | |
| static int migration_completion_precopy(MigrationState *s,
 | |
|                                         int *current_active_state)
 | |
| {
 | |
|     int ret;
 | |
| 
 | |
|     bql_lock();
 | |
| 
 | |
|     if (!migrate_mode_is_cpr(s)) {
 | |
|         ret = migration_stop_vm(s, RUN_STATE_FINISH_MIGRATE);
 | |
|         if (ret < 0) {
 | |
|             goto out_unlock;
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     ret = migration_maybe_pause(s, current_active_state,
 | |
|                                 MIGRATION_STATUS_DEVICE);
 | |
|     if (ret < 0) {
 | |
|         goto out_unlock;
 | |
|     }
 | |
| 
 | |
|     /*
 | |
|      * Inactivate disks except in COLO, and track that we have done so in order
 | |
|      * to remember to reactivate them if migration fails or is cancelled.
 | |
|      */
 | |
|     s->block_inactive = !migrate_colo();
 | |
|     migration_rate_set(RATE_LIMIT_DISABLED);
 | |
|     ret = qemu_savevm_state_complete_precopy(s->to_dst_file, false,
 | |
|                                              s->block_inactive);
 | |
| out_unlock:
 | |
|     bql_unlock();
 | |
|     return ret;
 | |
| }
 | |
| 
 | |
| static void migration_completion_postcopy(MigrationState *s)
 | |
| {
 | |
|     trace_migration_completion_postcopy_end();
 | |
| 
 | |
|     bql_lock();
 | |
|     qemu_savevm_state_complete_postcopy(s->to_dst_file);
 | |
|     bql_unlock();
 | |
| 
 | |
|     /*
 | |
|      * Shutdown the postcopy fast path thread.  This is only needed when dest
 | |
|      * QEMU binary is old (7.1/7.2).  QEMU 8.0+ doesn't need this.
 | |
|      */
 | |
|     if (migrate_postcopy_preempt() && s->preempt_pre_7_2) {
 | |
|         postcopy_preempt_shutdown_file(s);
 | |
|     }
 | |
| 
 | |
|     trace_migration_completion_postcopy_end_after_complete();
 | |
| }
 | |
| 
 | |
| static void migration_completion_failed(MigrationState *s,
 | |
|                                         int current_active_state)
 | |
| {
 | |
|     if (s->block_inactive && (s->state == MIGRATION_STATUS_ACTIVE ||
 | |
|                               s->state == MIGRATION_STATUS_DEVICE)) {
 | |
|         /*
 | |
|          * If not doing postcopy, vm_start() will be called: let's
 | |
|          * regain control on images.
 | |
|          */
 | |
|         Error *local_err = NULL;
 | |
| 
 | |
|         bql_lock();
 | |
|         bdrv_activate_all(&local_err);
 | |
|         if (local_err) {
 | |
|             error_report_err(local_err);
 | |
|         } else {
 | |
|             s->block_inactive = false;
 | |
|         }
 | |
|         bql_unlock();
 | |
|     }
 | |
| 
 | |
|     migrate_set_state(&s->state, current_active_state,
 | |
|                       MIGRATION_STATUS_FAILED);
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * migration_completion: Used by migration_thread when there's not much left.
 | |
|  *   The caller 'breaks' the loop when this returns.
 | |
|  *
 | |
|  * @s: Current migration state
 | |
|  */
 | |
| static void migration_completion(MigrationState *s)
 | |
| {
 | |
|     int ret = 0;
 | |
|     int current_active_state = s->state;
 | |
| 
 | |
|     if (s->state == MIGRATION_STATUS_ACTIVE) {
 | |
|         ret = migration_completion_precopy(s, ¤t_active_state);
 | |
|     } else if (s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE) {
 | |
|         migration_completion_postcopy(s);
 | |
|     } else {
 | |
|         ret = -1;
 | |
|     }
 | |
| 
 | |
|     if (ret < 0) {
 | |
|         goto fail;
 | |
|     }
 | |
| 
 | |
|     if (close_return_path_on_source(s)) {
 | |
|         goto fail;
 | |
|     }
 | |
| 
 | |
|     if (qemu_file_get_error(s->to_dst_file)) {
 | |
|         trace_migration_completion_file_err();
 | |
|         goto fail;
 | |
|     }
 | |
| 
 | |
|     if (migrate_colo() && s->state == MIGRATION_STATUS_ACTIVE) {
 | |
|         /* COLO does not support postcopy */
 | |
|         migrate_set_state(&s->state, MIGRATION_STATUS_ACTIVE,
 | |
|                           MIGRATION_STATUS_COLO);
 | |
|     } else {
 | |
|         migration_completion_end(s);
 | |
|     }
 | |
| 
 | |
|     return;
 | |
| 
 | |
| fail:
 | |
|     migration_completion_failed(s, current_active_state);
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * bg_migration_completion: Used by bg_migration_thread when after all the
 | |
|  *   RAM has been saved. The caller 'breaks' the loop when this returns.
 | |
|  *
 | |
|  * @s: Current migration state
 | |
|  */
 | |
| static void bg_migration_completion(MigrationState *s)
 | |
| {
 | |
|     int current_active_state = s->state;
 | |
| 
 | |
|     if (s->state == MIGRATION_STATUS_ACTIVE) {
 | |
|         /*
 | |
|          * By this moment we have RAM content saved into the migration stream.
 | |
|          * The next step is to flush the non-RAM content (device state)
 | |
|          * right after the ram content. The device state has been stored into
 | |
|          * the temporary buffer before RAM saving started.
 | |
|          */
 | |
|         qemu_put_buffer(s->to_dst_file, s->bioc->data, s->bioc->usage);
 | |
|         qemu_fflush(s->to_dst_file);
 | |
|     } else if (s->state == MIGRATION_STATUS_CANCELLING) {
 | |
|         goto fail;
 | |
|     }
 | |
| 
 | |
|     if (qemu_file_get_error(s->to_dst_file)) {
 | |
|         trace_migration_completion_file_err();
 | |
|         goto fail;
 | |
|     }
 | |
| 
 | |
|     migration_completion_end(s);
 | |
|     return;
 | |
| 
 | |
| fail:
 | |
|     migrate_set_state(&s->state, current_active_state,
 | |
|                       MIGRATION_STATUS_FAILED);
 | |
| }
 | |
| 
 | |
| typedef enum MigThrError {
 | |
|     /* No error detected */
 | |
|     MIG_THR_ERR_NONE = 0,
 | |
|     /* Detected error, but resumed successfully */
 | |
|     MIG_THR_ERR_RECOVERED = 1,
 | |
|     /* Detected fatal error, need to exit */
 | |
|     MIG_THR_ERR_FATAL = 2,
 | |
| } MigThrError;
 | |
| 
 | |
| static int postcopy_resume_handshake(MigrationState *s)
 | |
| {
 | |
|     qemu_savevm_send_postcopy_resume(s->to_dst_file);
 | |
| 
 | |
|     while (s->state == MIGRATION_STATUS_POSTCOPY_RECOVER) {
 | |
|         if (migration_rp_wait(s)) {
 | |
|             return -1;
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     if (s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE) {
 | |
|         return 0;
 | |
|     }
 | |
| 
 | |
|     return -1;
 | |
| }
 | |
| 
 | |
| /* Return zero if success, or <0 for error */
 | |
| static int postcopy_do_resume(MigrationState *s)
 | |
| {
 | |
|     int ret;
 | |
| 
 | |
|     /*
 | |
|      * Call all the resume_prepare() hooks, so that modules can be
 | |
|      * ready for the migration resume.
 | |
|      */
 | |
|     ret = qemu_savevm_state_resume_prepare(s);
 | |
|     if (ret) {
 | |
|         error_report("%s: resume_prepare() failure detected: %d",
 | |
|                      __func__, ret);
 | |
|         return ret;
 | |
|     }
 | |
| 
 | |
|     /*
 | |
|      * If preempt is enabled, re-establish the preempt channel.  Note that
 | |
|      * we do it after resume prepare to make sure the main channel will be
 | |
|      * created before the preempt channel.  E.g. with weak network, the
 | |
|      * dest QEMU may get messed up with the preempt and main channels on
 | |
|      * the order of connection setup.  This guarantees the correct order.
 | |
|      */
 | |
|     ret = postcopy_preempt_establish_channel(s);
 | |
|     if (ret) {
 | |
|         error_report("%s: postcopy_preempt_establish_channel(): %d",
 | |
|                      __func__, ret);
 | |
|         return ret;
 | |
|     }
 | |
| 
 | |
|     /*
 | |
|      * Last handshake with destination on the resume (destination will
 | |
|      * switch to postcopy-active afterwards)
 | |
|      */
 | |
|     ret = postcopy_resume_handshake(s);
 | |
|     if (ret) {
 | |
|         error_report("%s: handshake failed: %d", __func__, ret);
 | |
|         return ret;
 | |
|     }
 | |
| 
 | |
|     return 0;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * We don't return until we are in a safe state to continue current
 | |
|  * postcopy migration.  Returns MIG_THR_ERR_RECOVERED if recovered, or
 | |
|  * MIG_THR_ERR_FATAL if unrecovery failure happened.
 | |
|  */
 | |
| static MigThrError postcopy_pause(MigrationState *s)
 | |
| {
 | |
|     assert(s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE);
 | |
| 
 | |
|     while (true) {
 | |
|         QEMUFile *file;
 | |
| 
 | |
|         /*
 | |
|          * We're already pausing, so ignore any errors on the return
 | |
|          * path and just wait for the thread to finish. It will be
 | |
|          * re-created when we resume.
 | |
|          */
 | |
|         close_return_path_on_source(s);
 | |
| 
 | |
|         /*
 | |
|          * Current channel is possibly broken. Release it.  Note that this is
 | |
|          * guaranteed even without lock because to_dst_file should only be
 | |
|          * modified by the migration thread.  That also guarantees that the
 | |
|          * unregister of yank is safe too without the lock.  It should be safe
 | |
|          * even to be within the qemu_file_lock, but we didn't do that to avoid
 | |
|          * taking more mutex (yank_lock) within qemu_file_lock.  TL;DR: we make
 | |
|          * the qemu_file_lock critical section as small as possible.
 | |
|          */
 | |
|         assert(s->to_dst_file);
 | |
|         migration_ioc_unregister_yank_from_file(s->to_dst_file);
 | |
|         qemu_mutex_lock(&s->qemu_file_lock);
 | |
|         file = s->to_dst_file;
 | |
|         s->to_dst_file = NULL;
 | |
|         qemu_mutex_unlock(&s->qemu_file_lock);
 | |
| 
 | |
|         qemu_file_shutdown(file);
 | |
|         qemu_fclose(file);
 | |
| 
 | |
|         migrate_set_state(&s->state, s->state,
 | |
|                           MIGRATION_STATUS_POSTCOPY_PAUSED);
 | |
| 
 | |
|         error_report("Detected IO failure for postcopy. "
 | |
|                      "Migration paused.");
 | |
| 
 | |
|         /*
 | |
|          * We wait until things fixed up. Then someone will setup the
 | |
|          * status back for us.
 | |
|          */
 | |
|         while (s->state == MIGRATION_STATUS_POSTCOPY_PAUSED) {
 | |
|             qemu_sem_wait(&s->postcopy_pause_sem);
 | |
|         }
 | |
| 
 | |
|         if (s->state == MIGRATION_STATUS_POSTCOPY_RECOVER) {
 | |
|             /* Woken up by a recover procedure. Give it a shot */
 | |
| 
 | |
|             /* Do the resume logic */
 | |
|             if (postcopy_do_resume(s) == 0) {
 | |
|                 /* Let's continue! */
 | |
|                 trace_postcopy_pause_continued();
 | |
|                 return MIG_THR_ERR_RECOVERED;
 | |
|             } else {
 | |
|                 /*
 | |
|                  * Something wrong happened during the recovery, let's
 | |
|                  * pause again. Pause is always better than throwing
 | |
|                  * data away.
 | |
|                  */
 | |
|                 continue;
 | |
|             }
 | |
|         } else {
 | |
|             /* This is not right... Time to quit. */
 | |
|             return MIG_THR_ERR_FATAL;
 | |
|         }
 | |
|     }
 | |
| }
 | |
| 
 | |
| static MigThrError migration_detect_error(MigrationState *s)
 | |
| {
 | |
|     int ret;
 | |
|     int state = s->state;
 | |
|     Error *local_error = NULL;
 | |
| 
 | |
|     if (state == MIGRATION_STATUS_CANCELLING ||
 | |
|         state == MIGRATION_STATUS_CANCELLED) {
 | |
|         /* End the migration, but don't set the state to failed */
 | |
|         return MIG_THR_ERR_FATAL;
 | |
|     }
 | |
| 
 | |
|     /*
 | |
|      * Try to detect any file errors.  Note that postcopy_qemufile_src will
 | |
|      * be NULL when postcopy preempt is not enabled.
 | |
|      */
 | |
|     ret = qemu_file_get_error_obj_any(s->to_dst_file,
 | |
|                                       s->postcopy_qemufile_src,
 | |
|                                       &local_error);
 | |
|     if (!ret) {
 | |
|         /* Everything is fine */
 | |
|         assert(!local_error);
 | |
|         return MIG_THR_ERR_NONE;
 | |
|     }
 | |
| 
 | |
|     if (local_error) {
 | |
|         migrate_set_error(s, local_error);
 | |
|         error_free(local_error);
 | |
|     }
 | |
| 
 | |
|     if (state == MIGRATION_STATUS_POSTCOPY_ACTIVE && ret) {
 | |
|         /*
 | |
|          * For postcopy, we allow the network to be down for a
 | |
|          * while. After that, it can be continued by a
 | |
|          * recovery phase.
 | |
|          */
 | |
|         return postcopy_pause(s);
 | |
|     } else {
 | |
|         /*
 | |
|          * For precopy (or postcopy with error outside IO), we fail
 | |
|          * with no time.
 | |
|          */
 | |
|         migrate_set_state(&s->state, state, MIGRATION_STATUS_FAILED);
 | |
|         trace_migration_thread_file_err();
 | |
| 
 | |
|         /* Time to stop the migration, now. */
 | |
|         return MIG_THR_ERR_FATAL;
 | |
|     }
 | |
| }
 | |
| 
 | |
| static void migration_completion_end(MigrationState *s)
 | |
| {
 | |
|     uint64_t bytes = migration_transferred_bytes();
 | |
|     int64_t end_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
 | |
|     int64_t transfer_time;
 | |
| 
 | |
|     /*
 | |
|      * Take the BQL here so that query-migrate on the QMP thread sees:
 | |
|      * - atomic update of s->total_time and s->mbps;
 | |
|      * - correct ordering of s->mbps update vs. s->state;
 | |
|      */
 | |
|     bql_lock();
 | |
|     migration_downtime_end(s);
 | |
|     s->total_time = end_time - s->start_time;
 | |
|     transfer_time = s->total_time - s->setup_time;
 | |
|     if (transfer_time) {
 | |
|         s->mbps = ((double) bytes * 8.0) / transfer_time / 1000;
 | |
|     }
 | |
| 
 | |
|     migrate_set_state(&s->state, s->state,
 | |
|                       MIGRATION_STATUS_COMPLETED);
 | |
|     bql_unlock();
 | |
| }
 | |
| 
 | |
| static void update_iteration_initial_status(MigrationState *s)
 | |
| {
 | |
|     /*
 | |
|      * Update these three fields at the same time to avoid mismatch info lead
 | |
|      * wrong speed calculation.
 | |
|      */
 | |
|     s->iteration_start_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
 | |
|     s->iteration_initial_bytes = migration_transferred_bytes();
 | |
|     s->iteration_initial_pages = ram_get_total_transferred_pages();
 | |
| }
 | |
| 
 | |
| static void migration_update_counters(MigrationState *s,
 | |
|                                       int64_t current_time)
 | |
| {
 | |
|     uint64_t transferred, transferred_pages, time_spent;
 | |
|     uint64_t current_bytes; /* bytes transferred since the beginning */
 | |
|     uint64_t switchover_bw;
 | |
|     /* Expected bandwidth when switching over to destination QEMU */
 | |
|     double expected_bw_per_ms;
 | |
|     double bandwidth;
 | |
| 
 | |
|     if (current_time < s->iteration_start_time + BUFFER_DELAY) {
 | |
|         return;
 | |
|     }
 | |
| 
 | |
|     switchover_bw = migrate_avail_switchover_bandwidth();
 | |
|     current_bytes = migration_transferred_bytes();
 | |
|     transferred = current_bytes - s->iteration_initial_bytes;
 | |
|     time_spent = current_time - s->iteration_start_time;
 | |
|     bandwidth = (double)transferred / time_spent;
 | |
| 
 | |
|     if (switchover_bw) {
 | |
|         /*
 | |
|          * If the user specified a switchover bandwidth, let's trust the
 | |
|          * user so that can be more accurate than what we estimated.
 | |
|          */
 | |
|         expected_bw_per_ms = switchover_bw / 1000;
 | |
|     } else {
 | |
|         /* If the user doesn't specify bandwidth, we use the estimated */
 | |
|         expected_bw_per_ms = bandwidth;
 | |
|     }
 | |
| 
 | |
|     s->threshold_size = expected_bw_per_ms * migrate_downtime_limit();
 | |
| 
 | |
|     s->mbps = (((double) transferred * 8.0) /
 | |
|                ((double) time_spent / 1000.0)) / 1000.0 / 1000.0;
 | |
| 
 | |
|     transferred_pages = ram_get_total_transferred_pages() -
 | |
|                             s->iteration_initial_pages;
 | |
|     s->pages_per_second = (double) transferred_pages /
 | |
|                              (((double) time_spent / 1000.0));
 | |
| 
 | |
|     /*
 | |
|      * if we haven't sent anything, we don't want to
 | |
|      * recalculate. 10000 is a small enough number for our purposes
 | |
|      */
 | |
|     if (stat64_get(&mig_stats.dirty_pages_rate) &&
 | |
|         transferred > 10000) {
 | |
|         s->expected_downtime =
 | |
|             stat64_get(&mig_stats.dirty_bytes_last_sync) / expected_bw_per_ms;
 | |
|     }
 | |
| 
 | |
|     migration_rate_reset();
 | |
| 
 | |
|     update_iteration_initial_status(s);
 | |
| 
 | |
|     trace_migrate_transferred(transferred, time_spent,
 | |
|                               /* Both in unit bytes/ms */
 | |
|                               bandwidth, switchover_bw / 1000,
 | |
|                               s->threshold_size);
 | |
| }
 | |
| 
 | |
| static bool migration_can_switchover(MigrationState *s)
 | |
| {
 | |
|     if (!migrate_switchover_ack()) {
 | |
|         return true;
 | |
|     }
 | |
| 
 | |
|     /* No reason to wait for switchover ACK if VM is stopped */
 | |
|     if (!runstate_is_running()) {
 | |
|         return true;
 | |
|     }
 | |
| 
 | |
|     return s->switchover_acked;
 | |
| }
 | |
| 
 | |
| /* Migration thread iteration status */
 | |
| typedef enum {
 | |
|     MIG_ITERATE_RESUME,         /* Resume current iteration */
 | |
|     MIG_ITERATE_SKIP,           /* Skip current iteration */
 | |
|     MIG_ITERATE_BREAK,          /* Break the loop */
 | |
| } MigIterateState;
 | |
| 
 | |
| /*
 | |
|  * Return true if continue to the next iteration directly, false
 | |
|  * otherwise.
 | |
|  */
 | |
| static MigIterateState migration_iteration_run(MigrationState *s)
 | |
| {
 | |
|     uint64_t must_precopy, can_postcopy;
 | |
|     Error *local_err = NULL;
 | |
|     bool in_postcopy = s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE;
 | |
|     bool can_switchover = migration_can_switchover(s);
 | |
| 
 | |
|     qemu_savevm_state_pending_estimate(&must_precopy, &can_postcopy);
 | |
|     uint64_t pending_size = must_precopy + can_postcopy;
 | |
| 
 | |
|     trace_migrate_pending_estimate(pending_size, must_precopy, can_postcopy);
 | |
| 
 | |
|     if (must_precopy <= s->threshold_size) {
 | |
|         qemu_savevm_state_pending_exact(&must_precopy, &can_postcopy);
 | |
|         pending_size = must_precopy + can_postcopy;
 | |
|         trace_migrate_pending_exact(pending_size, must_precopy, can_postcopy);
 | |
|     }
 | |
| 
 | |
|     if ((!pending_size || pending_size < s->threshold_size) && can_switchover) {
 | |
|         trace_migration_thread_low_pending(pending_size);
 | |
|         migration_completion(s);
 | |
|         return MIG_ITERATE_BREAK;
 | |
|     }
 | |
| 
 | |
|     /* Still a significant amount to transfer */
 | |
|     if (!in_postcopy && must_precopy <= s->threshold_size && can_switchover &&
 | |
|         qatomic_read(&s->start_postcopy)) {
 | |
|         if (postcopy_start(s, &local_err)) {
 | |
|             migrate_set_error(s, local_err);
 | |
|             error_report_err(local_err);
 | |
|         }
 | |
|         return MIG_ITERATE_SKIP;
 | |
|     }
 | |
| 
 | |
|     /* Just another iteration step */
 | |
|     qemu_savevm_state_iterate(s->to_dst_file, in_postcopy);
 | |
|     return MIG_ITERATE_RESUME;
 | |
| }
 | |
| 
 | |
| static void migration_iteration_finish(MigrationState *s)
 | |
| {
 | |
|     /* If we enabled cpu throttling for auto-converge, turn it off. */
 | |
|     cpu_throttle_stop();
 | |
| 
 | |
|     bql_lock();
 | |
|     switch (s->state) {
 | |
|     case MIGRATION_STATUS_COMPLETED:
 | |
|         runstate_set(RUN_STATE_POSTMIGRATE);
 | |
|         break;
 | |
|     case MIGRATION_STATUS_COLO:
 | |
|         assert(migrate_colo());
 | |
|         migrate_start_colo_process(s);
 | |
|         s->vm_old_state = RUN_STATE_RUNNING;
 | |
|         /* Fallthrough */
 | |
|     case MIGRATION_STATUS_FAILED:
 | |
|     case MIGRATION_STATUS_CANCELLED:
 | |
|     case MIGRATION_STATUS_CANCELLING:
 | |
|         if (runstate_is_live(s->vm_old_state)) {
 | |
|             if (!runstate_check(RUN_STATE_SHUTDOWN)) {
 | |
|                 vm_start();
 | |
|             }
 | |
|         } else {
 | |
|             if (runstate_check(RUN_STATE_FINISH_MIGRATE)) {
 | |
|                 runstate_set(s->vm_old_state);
 | |
|             }
 | |
|         }
 | |
|         break;
 | |
| 
 | |
|     default:
 | |
|         /* Should not reach here, but if so, forgive the VM. */
 | |
|         error_report("%s: Unknown ending state %d", __func__, s->state);
 | |
|         break;
 | |
|     }
 | |
| 
 | |
|     migration_bh_schedule(migrate_fd_cleanup_bh, s);
 | |
|     bql_unlock();
 | |
| }
 | |
| 
 | |
| static void bg_migration_iteration_finish(MigrationState *s)
 | |
| {
 | |
|     /*
 | |
|      * Stop tracking RAM writes - un-protect memory, un-register UFFD
 | |
|      * memory ranges, flush kernel wait queues and wake up threads
 | |
|      * waiting for write fault to be resolved.
 | |
|      */
 | |
|     ram_write_tracking_stop();
 | |
| 
 | |
|     bql_lock();
 | |
|     switch (s->state) {
 | |
|     case MIGRATION_STATUS_COMPLETED:
 | |
|     case MIGRATION_STATUS_ACTIVE:
 | |
|     case MIGRATION_STATUS_FAILED:
 | |
|     case MIGRATION_STATUS_CANCELLED:
 | |
|     case MIGRATION_STATUS_CANCELLING:
 | |
|         break;
 | |
| 
 | |
|     default:
 | |
|         /* Should not reach here, but if so, forgive the VM. */
 | |
|         error_report("%s: Unknown ending state %d", __func__, s->state);
 | |
|         break;
 | |
|     }
 | |
| 
 | |
|     migration_bh_schedule(migrate_fd_cleanup_bh, s);
 | |
|     bql_unlock();
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Return true if continue to the next iteration directly, false
 | |
|  * otherwise.
 | |
|  */
 | |
| static MigIterateState bg_migration_iteration_run(MigrationState *s)
 | |
| {
 | |
|     int res;
 | |
| 
 | |
|     res = qemu_savevm_state_iterate(s->to_dst_file, false);
 | |
|     if (res > 0) {
 | |
|         bg_migration_completion(s);
 | |
|         return MIG_ITERATE_BREAK;
 | |
|     }
 | |
| 
 | |
|     return MIG_ITERATE_RESUME;
 | |
| }
 | |
| 
 | |
| void migration_make_urgent_request(void)
 | |
| {
 | |
|     qemu_sem_post(&migrate_get_current()->rate_limit_sem);
 | |
| }
 | |
| 
 | |
| void migration_consume_urgent_request(void)
 | |
| {
 | |
|     qemu_sem_wait(&migrate_get_current()->rate_limit_sem);
 | |
| }
 | |
| 
 | |
| /* Returns true if the rate limiting was broken by an urgent request */
 | |
| bool migration_rate_limit(void)
 | |
| {
 | |
|     int64_t now = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
 | |
|     MigrationState *s = migrate_get_current();
 | |
| 
 | |
|     bool urgent = false;
 | |
|     migration_update_counters(s, now);
 | |
|     if (migration_rate_exceeded(s->to_dst_file)) {
 | |
| 
 | |
|         if (qemu_file_get_error(s->to_dst_file)) {
 | |
|             return false;
 | |
|         }
 | |
|         /*
 | |
|          * Wait for a delay to do rate limiting OR
 | |
|          * something urgent to post the semaphore.
 | |
|          */
 | |
|         int ms = s->iteration_start_time + BUFFER_DELAY - now;
 | |
|         trace_migration_rate_limit_pre(ms);
 | |
|         if (qemu_sem_timedwait(&s->rate_limit_sem, ms) == 0) {
 | |
|             /*
 | |
|              * We were woken by one or more urgent things but
 | |
|              * the timedwait will have consumed one of them.
 | |
|              * The service routine for the urgent wake will dec
 | |
|              * the semaphore itself for each item it consumes,
 | |
|              * so add this one we just eat back.
 | |
|              */
 | |
|             qemu_sem_post(&s->rate_limit_sem);
 | |
|             urgent = true;
 | |
|         }
 | |
|         trace_migration_rate_limit_post(urgent);
 | |
|     }
 | |
|     return urgent;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * if failover devices are present, wait they are completely
 | |
|  * unplugged
 | |
|  */
 | |
| 
 | |
| static void qemu_savevm_wait_unplug(MigrationState *s, int old_state,
 | |
|                                     int new_state)
 | |
| {
 | |
|     if (qemu_savevm_state_guest_unplug_pending()) {
 | |
|         migrate_set_state(&s->state, old_state, MIGRATION_STATUS_WAIT_UNPLUG);
 | |
| 
 | |
|         while (s->state == MIGRATION_STATUS_WAIT_UNPLUG &&
 | |
|                qemu_savevm_state_guest_unplug_pending()) {
 | |
|             qemu_sem_timedwait(&s->wait_unplug_sem, 250);
 | |
|         }
 | |
|         if (s->state != MIGRATION_STATUS_WAIT_UNPLUG) {
 | |
|             int timeout = 120; /* 30 seconds */
 | |
|             /*
 | |
|              * migration has been canceled
 | |
|              * but as we have started an unplug we must wait the end
 | |
|              * to be able to plug back the card
 | |
|              */
 | |
|             while (timeout-- && qemu_savevm_state_guest_unplug_pending()) {
 | |
|                 qemu_sem_timedwait(&s->wait_unplug_sem, 250);
 | |
|             }
 | |
|             if (qemu_savevm_state_guest_unplug_pending() &&
 | |
|                 !qtest_enabled()) {
 | |
|                 warn_report("migration: partially unplugged device on "
 | |
|                             "failure");
 | |
|             }
 | |
|         }
 | |
| 
 | |
|         migrate_set_state(&s->state, MIGRATION_STATUS_WAIT_UNPLUG, new_state);
 | |
|     } else {
 | |
|         migrate_set_state(&s->state, old_state, new_state);
 | |
|     }
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Master migration thread on the source VM.
 | |
|  * It drives the migration and pumps the data down the outgoing channel.
 | |
|  */
 | |
| static void *migration_thread(void *opaque)
 | |
| {
 | |
|     MigrationState *s = opaque;
 | |
|     MigrationThread *thread = NULL;
 | |
|     int64_t setup_start = qemu_clock_get_ms(QEMU_CLOCK_HOST);
 | |
|     MigThrError thr_error;
 | |
|     bool urgent = false;
 | |
| 
 | |
|     thread = migration_threads_add("live_migration", qemu_get_thread_id());
 | |
| 
 | |
|     rcu_register_thread();
 | |
| 
 | |
|     object_ref(OBJECT(s));
 | |
|     update_iteration_initial_status(s);
 | |
| 
 | |
|     if (!multifd_send_setup()) {
 | |
|         goto out;
 | |
|     }
 | |
| 
 | |
|     bql_lock();
 | |
|     qemu_savevm_state_header(s->to_dst_file);
 | |
|     bql_unlock();
 | |
| 
 | |
|     /*
 | |
|      * If we opened the return path, we need to make sure dst has it
 | |
|      * opened as well.
 | |
|      */
 | |
|     if (s->rp_state.rp_thread_created) {
 | |
|         /* Now tell the dest that it should open its end so it can reply */
 | |
|         qemu_savevm_send_open_return_path(s->to_dst_file);
 | |
| 
 | |
|         /* And do a ping that will make stuff easier to debug */
 | |
|         qemu_savevm_send_ping(s->to_dst_file, 1);
 | |
|     }
 | |
| 
 | |
|     if (migrate_postcopy()) {
 | |
|         /*
 | |
|          * Tell the destination that we *might* want to do postcopy later;
 | |
|          * if the other end can't do postcopy it should fail now, nice and
 | |
|          * early.
 | |
|          */
 | |
|         qemu_savevm_send_postcopy_advise(s->to_dst_file);
 | |
|     }
 | |
| 
 | |
|     if (migrate_colo()) {
 | |
|         /* Notify migration destination that we enable COLO */
 | |
|         qemu_savevm_send_colo_enable(s->to_dst_file);
 | |
|     }
 | |
| 
 | |
|     bql_lock();
 | |
|     qemu_savevm_state_setup(s->to_dst_file);
 | |
|     bql_unlock();
 | |
| 
 | |
|     qemu_savevm_wait_unplug(s, MIGRATION_STATUS_SETUP,
 | |
|                                MIGRATION_STATUS_ACTIVE);
 | |
| 
 | |
|     s->setup_time = qemu_clock_get_ms(QEMU_CLOCK_HOST) - setup_start;
 | |
| 
 | |
|     trace_migration_thread_setup_complete();
 | |
| 
 | |
|     while (migration_is_active(s)) {
 | |
|         if (urgent || !migration_rate_exceeded(s->to_dst_file)) {
 | |
|             MigIterateState iter_state = migration_iteration_run(s);
 | |
|             if (iter_state == MIG_ITERATE_SKIP) {
 | |
|                 continue;
 | |
|             } else if (iter_state == MIG_ITERATE_BREAK) {
 | |
|                 break;
 | |
|             }
 | |
|         }
 | |
| 
 | |
|         /*
 | |
|          * Try to detect any kind of failures, and see whether we
 | |
|          * should stop the migration now.
 | |
|          */
 | |
|         thr_error = migration_detect_error(s);
 | |
|         if (thr_error == MIG_THR_ERR_FATAL) {
 | |
|             /* Stop migration */
 | |
|             break;
 | |
|         } else if (thr_error == MIG_THR_ERR_RECOVERED) {
 | |
|             /*
 | |
|              * Just recovered from a e.g. network failure, reset all
 | |
|              * the local variables. This is important to avoid
 | |
|              * breaking transferred_bytes and bandwidth calculation
 | |
|              */
 | |
|             update_iteration_initial_status(s);
 | |
|         }
 | |
| 
 | |
|         urgent = migration_rate_limit();
 | |
|     }
 | |
| 
 | |
| out:
 | |
|     trace_migration_thread_after_loop();
 | |
|     migration_iteration_finish(s);
 | |
|     object_unref(OBJECT(s));
 | |
|     rcu_unregister_thread();
 | |
|     migration_threads_remove(thread);
 | |
|     return NULL;
 | |
| }
 | |
| 
 | |
| static void bg_migration_vm_start_bh(void *opaque)
 | |
| {
 | |
|     MigrationState *s = opaque;
 | |
| 
 | |
|     vm_resume(s->vm_old_state);
 | |
|     migration_downtime_end(s);
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * Background snapshot thread, based on live migration code.
 | |
|  * This is an alternative implementation of live migration mechanism
 | |
|  * introduced specifically to support background snapshots.
 | |
|  *
 | |
|  * It takes advantage of userfault_fd write protection mechanism introduced
 | |
|  * in v5.7 kernel. Compared to existing dirty page logging migration much
 | |
|  * lesser stream traffic is produced resulting in smaller snapshot images,
 | |
|  * simply cause of no page duplicates can get into the stream.
 | |
|  *
 | |
|  * Another key point is that generated vmstate stream reflects machine state
 | |
|  * 'frozen' at the beginning of snapshot creation compared to dirty page logging
 | |
|  * mechanism, which effectively results in that saved snapshot is the state of VM
 | |
|  * at the end of the process.
 | |
|  */
 | |
| static void *bg_migration_thread(void *opaque)
 | |
| {
 | |
|     MigrationState *s = opaque;
 | |
|     int64_t setup_start;
 | |
|     MigThrError thr_error;
 | |
|     QEMUFile *fb;
 | |
|     bool early_fail = true;
 | |
| 
 | |
|     rcu_register_thread();
 | |
|     object_ref(OBJECT(s));
 | |
| 
 | |
|     migration_rate_set(RATE_LIMIT_DISABLED);
 | |
| 
 | |
|     setup_start = qemu_clock_get_ms(QEMU_CLOCK_HOST);
 | |
|     /*
 | |
|      * We want to save vmstate for the moment when migration has been
 | |
|      * initiated but also we want to save RAM content while VM is running.
 | |
|      * The RAM content should appear first in the vmstate. So, we first
 | |
|      * stash the non-RAM part of the vmstate to the temporary buffer,
 | |
|      * then write RAM part of the vmstate to the migration stream
 | |
|      * with vCPUs running and, finally, write stashed non-RAM part of
 | |
|      * the vmstate from the buffer to the migration stream.
 | |
|      */
 | |
|     s->bioc = qio_channel_buffer_new(512 * 1024);
 | |
|     qio_channel_set_name(QIO_CHANNEL(s->bioc), "vmstate-buffer");
 | |
|     fb = qemu_file_new_output(QIO_CHANNEL(s->bioc));
 | |
|     object_unref(OBJECT(s->bioc));
 | |
| 
 | |
|     update_iteration_initial_status(s);
 | |
| 
 | |
|     /*
 | |
|      * Prepare for tracking memory writes with UFFD-WP - populate
 | |
|      * RAM pages before protecting.
 | |
|      */
 | |
| #ifdef __linux__
 | |
|     ram_write_tracking_prepare();
 | |
| #endif
 | |
| 
 | |
|     bql_lock();
 | |
|     qemu_savevm_state_header(s->to_dst_file);
 | |
|     qemu_savevm_state_setup(s->to_dst_file);
 | |
|     bql_unlock();
 | |
| 
 | |
|     qemu_savevm_wait_unplug(s, MIGRATION_STATUS_SETUP,
 | |
|                                MIGRATION_STATUS_ACTIVE);
 | |
| 
 | |
|     s->setup_time = qemu_clock_get_ms(QEMU_CLOCK_HOST) - setup_start;
 | |
| 
 | |
|     trace_migration_thread_setup_complete();
 | |
| 
 | |
|     bql_lock();
 | |
| 
 | |
|     if (migration_stop_vm(s, RUN_STATE_PAUSED)) {
 | |
|         goto fail;
 | |
|     }
 | |
|     /*
 | |
|      * Put vCPUs in sync with shadow context structures, then
 | |
|      * save their state to channel-buffer along with devices.
 | |
|      */
 | |
|     cpu_synchronize_all_states();
 | |
|     if (qemu_savevm_state_complete_precopy_non_iterable(fb, false, false)) {
 | |
|         goto fail;
 | |
|     }
 | |
|     /*
 | |
|      * Since we are going to get non-iterable state data directly
 | |
|      * from s->bioc->data, explicit flush is needed here.
 | |
|      */
 | |
|     qemu_fflush(fb);
 | |
| 
 | |
|     /* Now initialize UFFD context and start tracking RAM writes */
 | |
|     if (ram_write_tracking_start()) {
 | |
|         goto fail;
 | |
|     }
 | |
|     early_fail = false;
 | |
| 
 | |
|     /*
 | |
|      * Start VM from BH handler to avoid write-fault lock here.
 | |
|      * UFFD-WP protection for the whole RAM is already enabled so
 | |
|      * calling VM state change notifiers from vm_start() would initiate
 | |
|      * writes to virtio VQs memory which is in write-protected region.
 | |
|      */
 | |
|     migration_bh_schedule(bg_migration_vm_start_bh, s);
 | |
|     bql_unlock();
 | |
| 
 | |
|     while (migration_is_active(s)) {
 | |
|         MigIterateState iter_state = bg_migration_iteration_run(s);
 | |
|         if (iter_state == MIG_ITERATE_SKIP) {
 | |
|             continue;
 | |
|         } else if (iter_state == MIG_ITERATE_BREAK) {
 | |
|             break;
 | |
|         }
 | |
| 
 | |
|         /*
 | |
|          * Try to detect any kind of failures, and see whether we
 | |
|          * should stop the migration now.
 | |
|          */
 | |
|         thr_error = migration_detect_error(s);
 | |
|         if (thr_error == MIG_THR_ERR_FATAL) {
 | |
|             /* Stop migration */
 | |
|             break;
 | |
|         }
 | |
| 
 | |
|         migration_update_counters(s, qemu_clock_get_ms(QEMU_CLOCK_REALTIME));
 | |
|     }
 | |
| 
 | |
|     trace_migration_thread_after_loop();
 | |
| 
 | |
| fail:
 | |
|     if (early_fail) {
 | |
|         migrate_set_state(&s->state, MIGRATION_STATUS_ACTIVE,
 | |
|                 MIGRATION_STATUS_FAILED);
 | |
|         bql_unlock();
 | |
|     }
 | |
| 
 | |
|     bg_migration_iteration_finish(s);
 | |
| 
 | |
|     qemu_fclose(fb);
 | |
|     object_unref(OBJECT(s));
 | |
|     rcu_unregister_thread();
 | |
| 
 | |
|     return NULL;
 | |
| }
 | |
| 
 | |
| void migrate_fd_connect(MigrationState *s, Error *error_in)
 | |
| {
 | |
|     Error *local_err = NULL;
 | |
|     uint64_t rate_limit;
 | |
|     bool resume = s->state == MIGRATION_STATUS_POSTCOPY_PAUSED;
 | |
|     int ret;
 | |
| 
 | |
|     /*
 | |
|      * If there's a previous error, free it and prepare for another one.
 | |
|      * Meanwhile if migration completes successfully, there won't have an error
 | |
|      * dumped when calling migrate_fd_cleanup().
 | |
|      */
 | |
|     migrate_error_free(s);
 | |
| 
 | |
|     s->expected_downtime = migrate_downtime_limit();
 | |
|     if (error_in) {
 | |
|         migrate_fd_error(s, error_in);
 | |
|         if (resume) {
 | |
|             /*
 | |
|              * Don't do cleanup for resume if channel is invalid, but only dump
 | |
|              * the error.  We wait for another channel connect from the user.
 | |
|              * The error_report still gives HMP user a hint on what failed.
 | |
|              * It's normally done in migrate_fd_cleanup(), but call it here
 | |
|              * explicitly.
 | |
|              */
 | |
|             error_report_err(error_copy(s->error));
 | |
|         } else {
 | |
|             migrate_fd_cleanup(s);
 | |
|         }
 | |
|         return;
 | |
|     }
 | |
| 
 | |
|     if (resume) {
 | |
|         /* This is a resumed migration */
 | |
|         rate_limit = migrate_max_postcopy_bandwidth();
 | |
|     } else {
 | |
|         /* This is a fresh new migration */
 | |
|         rate_limit = migrate_max_bandwidth();
 | |
| 
 | |
|         /* Notify before starting migration thread */
 | |
|         if (migration_call_notifiers(s, MIG_EVENT_PRECOPY_SETUP, &local_err)) {
 | |
|             goto fail;
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     migration_rate_set(rate_limit);
 | |
|     qemu_file_set_blocking(s->to_dst_file, true);
 | |
| 
 | |
|     /*
 | |
|      * Open the return path. For postcopy, it is used exclusively. For
 | |
|      * precopy, only if user specified "return-path" capability would
 | |
|      * QEMU uses the return path.
 | |
|      */
 | |
|     if (migrate_postcopy_ram() || migrate_return_path()) {
 | |
|         if (open_return_path_on_source(s)) {
 | |
|             error_setg(&local_err, "Unable to open return-path for postcopy");
 | |
|             goto fail;
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     /*
 | |
|      * This needs to be done before resuming a postcopy.  Note: for newer
 | |
|      * QEMUs we will delay the channel creation until postcopy_start(), to
 | |
|      * avoid disorder of channel creations.
 | |
|      */
 | |
|     if (migrate_postcopy_preempt() && s->preempt_pre_7_2) {
 | |
|         postcopy_preempt_setup(s);
 | |
|     }
 | |
| 
 | |
|     if (resume) {
 | |
|         /* Wakeup the main migration thread to do the recovery */
 | |
|         migrate_set_state(&s->state, MIGRATION_STATUS_POSTCOPY_PAUSED,
 | |
|                           MIGRATION_STATUS_POSTCOPY_RECOVER);
 | |
|         qemu_sem_post(&s->postcopy_pause_sem);
 | |
|         return;
 | |
|     }
 | |
| 
 | |
|     if (migrate_mode_is_cpr(s)) {
 | |
|         ret = migration_stop_vm(s, RUN_STATE_FINISH_MIGRATE);
 | |
|         if (ret < 0) {
 | |
|             error_setg(&local_err, "migration_stop_vm failed, error %d", -ret);
 | |
|             goto fail;
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     if (migrate_background_snapshot()) {
 | |
|         qemu_thread_create(&s->thread, "bg_snapshot",
 | |
|                 bg_migration_thread, s, QEMU_THREAD_JOINABLE);
 | |
|     } else {
 | |
|         qemu_thread_create(&s->thread, "live_migration",
 | |
|                 migration_thread, s, QEMU_THREAD_JOINABLE);
 | |
|     }
 | |
|     s->migration_thread_running = true;
 | |
|     return;
 | |
| 
 | |
| fail:
 | |
|     migrate_set_error(s, local_err);
 | |
|     migrate_set_state(&s->state, s->state, MIGRATION_STATUS_FAILED);
 | |
|     error_report_err(local_err);
 | |
|     migrate_fd_cleanup(s);
 | |
| }
 | |
| 
 | |
| static void migration_class_init(ObjectClass *klass, void *data)
 | |
| {
 | |
|     DeviceClass *dc = DEVICE_CLASS(klass);
 | |
| 
 | |
|     dc->user_creatable = false;
 | |
|     device_class_set_props(dc, migration_properties);
 | |
| }
 | |
| 
 | |
| static void migration_instance_finalize(Object *obj)
 | |
| {
 | |
|     MigrationState *ms = MIGRATION_OBJ(obj);
 | |
| 
 | |
|     qemu_mutex_destroy(&ms->error_mutex);
 | |
|     qemu_mutex_destroy(&ms->qemu_file_lock);
 | |
|     qemu_sem_destroy(&ms->wait_unplug_sem);
 | |
|     qemu_sem_destroy(&ms->rate_limit_sem);
 | |
|     qemu_sem_destroy(&ms->pause_sem);
 | |
|     qemu_sem_destroy(&ms->postcopy_pause_sem);
 | |
|     qemu_sem_destroy(&ms->rp_state.rp_sem);
 | |
|     qemu_sem_destroy(&ms->rp_state.rp_pong_acks);
 | |
|     qemu_sem_destroy(&ms->postcopy_qemufile_src_sem);
 | |
|     error_free(ms->error);
 | |
| }
 | |
| 
 | |
| static void migration_instance_init(Object *obj)
 | |
| {
 | |
|     MigrationState *ms = MIGRATION_OBJ(obj);
 | |
| 
 | |
|     ms->state = MIGRATION_STATUS_NONE;
 | |
|     ms->mbps = -1;
 | |
|     ms->pages_per_second = -1;
 | |
|     qemu_sem_init(&ms->pause_sem, 0);
 | |
|     qemu_mutex_init(&ms->error_mutex);
 | |
| 
 | |
|     migrate_params_init(&ms->parameters);
 | |
| 
 | |
|     qemu_sem_init(&ms->postcopy_pause_sem, 0);
 | |
|     qemu_sem_init(&ms->rp_state.rp_sem, 0);
 | |
|     qemu_sem_init(&ms->rp_state.rp_pong_acks, 0);
 | |
|     qemu_sem_init(&ms->rate_limit_sem, 0);
 | |
|     qemu_sem_init(&ms->wait_unplug_sem, 0);
 | |
|     qemu_sem_init(&ms->postcopy_qemufile_src_sem, 0);
 | |
|     qemu_mutex_init(&ms->qemu_file_lock);
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Return true if check pass, false otherwise. Error will be put
 | |
|  * inside errp if provided.
 | |
|  */
 | |
| static bool migration_object_check(MigrationState *ms, Error **errp)
 | |
| {
 | |
|     /* Assuming all off */
 | |
|     bool old_caps[MIGRATION_CAPABILITY__MAX] = { 0 };
 | |
| 
 | |
|     if (!migrate_params_check(&ms->parameters, errp)) {
 | |
|         return false;
 | |
|     }
 | |
| 
 | |
|     return migrate_caps_check(old_caps, ms->capabilities, errp);
 | |
| }
 | |
| 
 | |
| static const TypeInfo migration_type = {
 | |
|     .name = TYPE_MIGRATION,
 | |
|     /*
 | |
|      * NOTE: TYPE_MIGRATION is not really a device, as the object is
 | |
|      * not created using qdev_new(), it is not attached to the qdev
 | |
|      * device tree, and it is never realized.
 | |
|      *
 | |
|      * TODO: Make this TYPE_OBJECT once QOM provides something like
 | |
|      * TYPE_DEVICE's "-global" properties.
 | |
|      */
 | |
|     .parent = TYPE_DEVICE,
 | |
|     .class_init = migration_class_init,
 | |
|     .class_size = sizeof(MigrationClass),
 | |
|     .instance_size = sizeof(MigrationState),
 | |
|     .instance_init = migration_instance_init,
 | |
|     .instance_finalize = migration_instance_finalize,
 | |
| };
 | |
| 
 | |
| static void register_migration_types(void)
 | |
| {
 | |
|     type_register_static(&migration_type);
 | |
| }
 | |
| 
 | |
| type_init(register_migration_types);
 |