xref: /openbmc/qemu/migration/multifd.h (revision 915f77b2)
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 num;
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, 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, Error **errp);
171 } MultiFDMethods;
172 
173 void multifd_register_ops(int method, MultiFDMethods *ops);
174 
175 #endif
176 
177