migration/multifd.h

   1 /*
   2  * Multifd common functions
   3  *
   4  * Copyright (c) 2019-2020 Red Hat Inc
   5  *
   6  * Authors:
   7  *  Juan Quintela <quintela@redhat.com>
   8  *
   9  * This work is licensed under the terms of the GNU GPL, version 2 or later.
  10  * See the COPYING file in the top-level directory.
  11  */
  12
  13 #ifndef QEMU_MIGRATION_MULTIFD_H
  14 #define QEMU_MIGRATION_MULTIFD_H
  15
  16 bool migrate_multifd_is_allowed(void);
  17 void migrate_protocol_allow_multifd(bool allow);
  18 int multifd_save_setup(Error **errp);
  19 void multifd_save_cleanup(void);
  20 int multifd_load_setup(Error **errp);
  21 int multifd_load_cleanup(Error **errp);
  22 bool multifd_recv_all_channels_created(void);
  23 bool multifd_recv_new_channel(QIOChannel *ioc, Error **errp);
  24 void multifd_recv_sync_main(void);
  25 void multifd_send_sync_main(QEMUFile *f);
  26 int multifd_queue_page(QEMUFile *f, RAMBlock *block, ram_addr_t offset);
  27
  28 /* Multifd Compression flags */
  29 #define MULTIFD_FLAG_SYNC (1 << 0)
  30
  31 /* We reserve 3 bits for compression methods */
  32 #define MULTIFD_FLAG_COMPRESSION_MASK (7 << 1)
  33 /* we need to be compatible. Before compression value was 0 */
  34 #define MULTIFD_FLAG_NOCOMP (0 << 1)
  35 #define MULTIFD_FLAG_ZLIB (1 << 1)
  36 #define MULTIFD_FLAG_ZSTD (2 << 1)
  37
  38 /* This value needs to be a multiple of qemu_target_page_size() */
  39 #define MULTIFD_PACKET_SIZE (512 * 1024)
  40
  41 typedef struct {
  42     uint32_t magic;
  43     uint32_t version;
  44     uint32_t flags;
  45     /* maximum number of allocated pages */
  46     uint32_t pages_alloc;
  47     uint32_t pages_used;
  48     /* size of the next packet that contains pages */
  49     uint32_t next_packet_size;
  50     uint64_t packet_num;
  51     uint64_t unused[4];    /* Reserved for future use */
  52     char ramblock[256];
  53     uint64_t offset[];
  54 } __attribute__((packed)) MultiFDPacket_t;
  55
  56 typedef struct {
  57     /* number of used pages */
  58     uint32_t used;
  59     /* number of allocated pages */
  60     uint32_t allocated;
  61     /* global number of generated multifd packets */
  62     uint64_t packet_num;
  63     /* offset of each page */
  64     ram_addr_t *offset;
  65     /* pointer to each page */
  66     struct iovec *iov;
  67     RAMBlock *block;
  68 } MultiFDPages_t;
  69
  70 typedef struct {
  71     /* this fields are not changed once the thread is created */
  72     /* channel number */
  73     uint8_t id;
  74     /* channel thread name */
  75     char *name;
  76     /* tls hostname */
  77     char *tls_hostname;
  78     /* channel thread id */
  79     QemuThread thread;
  80     /* communication channel */
  81     QIOChannel *c;
  82     /* sem where to wait for more work */
  83     QemuSemaphore sem;
  84     /* this mutex protects the following parameters */
  85     QemuMutex mutex;
  86     /* is this channel thread running */
  87     bool running;
  88     /* should this thread finish */
  89     bool quit;
  90     /* is the yank function registered */
  91     bool registered_yank;
  92     /* thread has work to do */
  93     int pending_job;
  94     /* array of pages to sent */
  95     MultiFDPages_t *pages;
  96     /* packet allocated len */
  97     uint32_t packet_len;
  98     /* pointer to the packet */
  99     MultiFDPacket_t *packet;
 100     /* multifd flags for each packet */
 101     uint32_t flags;
 102     /* size of the next packet that contains pages */
 103     uint32_t next_packet_size;
 104     /* global number of generated multifd packets */
 105     uint64_t packet_num;
 106     /* thread local variables */
 107     /* packets sent through this channel */
 108     uint64_t num_packets;
 109     /* pages sent through this channel */
 110     uint64_t num_pages;
 111     /* syncs main thread and channels */
 112     QemuSemaphore sem_sync;
 113     /* used for compression methods */
 114     void *data;
 115 }  MultiFDSendParams;
 116
 117 typedef struct {
 118     /* this fields are not changed once the thread is created */
 119     /* channel number */
 120     uint8_t id;
 121     /* channel thread name */
 122     char *name;
 123     /* channel thread id */
 124     QemuThread thread;
 125     /* communication channel */
 126     QIOChannel *c;
 127     /* this mutex protects the following parameters */
 128     QemuMutex mutex;
 129     /* is this channel thread running */
 130     bool running;
 131     /* should this thread finish */
 132     bool quit;
 133     /* array of pages to receive */
 134     MultiFDPages_t *pages;
 135     /* packet allocated len */
 136     uint32_t packet_len;
 137     /* pointer to the packet */
 138     MultiFDPacket_t *packet;
 139     /* multifd flags for each packet */
 140     uint32_t flags;
 141     /* global number of generated multifd packets */
 142     uint64_t packet_num;
 143     /* thread local variables */
 144     /* size of the next packet that contains pages */
 145     uint32_t next_packet_size;
 146     /* packets sent through this channel */
 147     uint64_t num_packets;
 148     /* pages sent through this channel */
 149     uint64_t num_pages;
 150     /* syncs main thread and channels */
 151     QemuSemaphore sem_sync;
 152     /* used for de-compression methods */
 153     void *data;
 154 } MultiFDRecvParams;
 155
 156 typedef struct {
 157     /* Setup for sending side */
 158     int (*send_setup)(MultiFDSendParams *p, Error **errp);
 159     /* Cleanup for sending side */
 160     void (*send_cleanup)(MultiFDSendParams *p, Error **errp);
 161     /* Prepare the send packet */
 162     int (*send_prepare)(MultiFDSendParams *p, uint32_t used, Error **errp);
 163     /* Write the send packet */
 164     int (*send_write)(MultiFDSendParams *p, uint32_t used, Error **errp);
 165     /* Setup for receiving side */
 166     int (*recv_setup)(MultiFDRecvParams *p, Error **errp);
 167     /* Cleanup for receiving side */
 168     void (*recv_cleanup)(MultiFDRecvParams *p);
 169     /* Read all pages */
 170     int (*recv_pages)(MultiFDRecvParams *p, uint32_t used, Error **errp);
 171 } MultiFDMethods;
 172
 173 void multifd_register_ops(int method, MultiFDMethods *ops);
 174
 175 #endif
 176