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 #include "ram.h"
17
18 typedef struct MultiFDRecvData MultiFDRecvData;
19
20 bool multifd_send_setup(void);
21 void multifd_send_shutdown(void);
22 void multifd_send_channel_created(void);
23 int multifd_recv_setup(Error **errp);
24 void multifd_recv_cleanup(void);
25 void multifd_recv_shutdown(void);
26 bool multifd_recv_all_channels_created(void);
27 void multifd_recv_new_channel(QIOChannel *ioc, Error **errp);
28 void multifd_recv_sync_main(void);
29 int multifd_send_sync_main(void);
30 bool multifd_queue_page(RAMBlock *block, ram_addr_t offset);
31 bool multifd_recv(void);
32 MultiFDRecvData *multifd_get_recv_data(void);
33
34 /* Multifd Compression flags */
35 #define MULTIFD_FLAG_SYNC (1 << 0)
36
37 /* We reserve 4 bits for compression methods */
38 #define MULTIFD_FLAG_COMPRESSION_MASK (0xf << 1)
39 /* we need to be compatible. Before compression value was 0 */
40 #define MULTIFD_FLAG_NOCOMP (0 << 1)
41 #define MULTIFD_FLAG_ZLIB (1 << 1)
42 #define MULTIFD_FLAG_ZSTD (2 << 1)
43 #define MULTIFD_FLAG_QPL (4 << 1)
44 #define MULTIFD_FLAG_UADK (8 << 1)
45
46 /* This value needs to be a multiple of qemu_target_page_size() */
47 #define MULTIFD_PACKET_SIZE (512 * 1024)
48
49 typedef struct {
50 uint32_t magic;
51 uint32_t version;
52 uint32_t flags;
53 /* maximum number of allocated pages */
54 uint32_t pages_alloc;
55 /* non zero pages */
56 uint32_t normal_pages;
57 /* size of the next packet that contains pages */
58 uint32_t next_packet_size;
59 uint64_t packet_num;
60 /* zero pages */
61 uint32_t zero_pages;
62 uint32_t unused32[1]; /* Reserved for future use */
63 uint64_t unused64[3]; /* Reserved for future use */
64 char ramblock[256];
65 /*
66 * This array contains the pointers to:
67 * - normal pages (initial normal_pages entries)
68 * - zero pages (following zero_pages entries)
69 */
70 uint64_t offset[];
71 } __attribute__((packed)) MultiFDPacket_t;
72
73 typedef struct {
74 /* number of used pages */
75 uint32_t num;
76 /* number of normal pages */
77 uint32_t normal_num;
78 /* number of allocated pages */
79 uint32_t allocated;
80 /* offset of each page */
81 ram_addr_t *offset;
82 RAMBlock *block;
83 } MultiFDPages_t;
84
85 struct MultiFDRecvData {
86 void *opaque;
87 size_t size;
88 /* for preadv */
89 off_t file_offset;
90 };
91
92 typedef struct {
93 /* Fields are only written at creating/deletion time */
94 /* No lock required for them, they are read only */
95
96 /* channel number */
97 uint8_t id;
98 /* channel thread name */
99 char *name;
100 /* channel thread id */
101 QemuThread thread;
102 bool thread_created;
103 QemuThread tls_thread;
104 bool tls_thread_created;
105 /* communication channel */
106 QIOChannel *c;
107 /* packet allocated len */
108 uint32_t packet_len;
109 /* guest page size */
110 uint32_t page_size;
111 /* number of pages in a full packet */
112 uint32_t page_count;
113 /* multifd flags for sending ram */
114 int write_flags;
115
116 /* sem where to wait for more work */
117 QemuSemaphore sem;
118 /* syncs main thread and channels */
119 QemuSemaphore sem_sync;
120
121 /* multifd flags for each packet */
122 uint32_t flags;
123 /*
124 * The sender thread has work to do if either of below boolean is set.
125 *
126 * @pending_job: a job is pending
127 * @pending_sync: a sync request is pending
128 *
129 * For both of these fields, they're only set by the requesters, and
130 * cleared by the multifd sender threads.
131 */
132 bool pending_job;
133 bool pending_sync;
134 /* array of pages to sent.
135 * The owner of 'pages' depends of 'pending_job' value:
136 * pending_job == 0 -> migration_thread can use it.
137 * pending_job != 0 -> multifd_channel can use it.
138 */
139 MultiFDPages_t *pages;
140
141 /* thread local variables. No locking required */
142
143 /* pointer to the packet */
144 MultiFDPacket_t *packet;
145 /* size of the next packet that contains pages */
146 uint32_t next_packet_size;
147 /* packets sent through this channel */
148 uint64_t packets_sent;
149 /* non zero pages sent through this channel */
150 uint64_t total_normal_pages;
151 /* zero pages sent through this channel */
152 uint64_t total_zero_pages;
153 /* buffers to send */
154 struct iovec *iov;
155 /* number of iovs used */
156 uint32_t iovs_num;
157 /* used for compression methods */
158 void *compress_data;
159 } MultiFDSendParams;
160
161 typedef struct {
162 /* Fields are only written at creating/deletion time */
163 /* No lock required for them, they are read only */
164
165 /* channel number */
166 uint8_t id;
167 /* channel thread name */
168 char *name;
169 /* channel thread id */
170 QemuThread thread;
171 bool thread_created;
172 /* communication channel */
173 QIOChannel *c;
174 /* packet allocated len */
175 uint32_t packet_len;
176 /* guest page size */
177 uint32_t page_size;
178 /* number of pages in a full packet */
179 uint32_t page_count;
180
181 /* syncs main thread and channels */
182 QemuSemaphore sem_sync;
183 /* sem where to wait for more work */
184 QemuSemaphore sem;
185
186 /* this mutex protects the following parameters */
187 QemuMutex mutex;
188 /* should this thread finish */
189 bool quit;
190 /* multifd flags for each packet */
191 uint32_t flags;
192 /* global number of generated multifd packets */
193 uint64_t packet_num;
194 int pending_job;
195 MultiFDRecvData *data;
196
197 /* thread local variables. No locking required */
198
199 /* pointer to the packet */
200 MultiFDPacket_t *packet;
201 /* size of the next packet that contains pages */
202 uint32_t next_packet_size;
203 /* packets received through this channel */
204 uint64_t packets_recved;
205 /* ramblock */
206 RAMBlock *block;
207 /* ramblock host address */
208 uint8_t *host;
209 /* non zero pages recv through this channel */
210 uint64_t total_normal_pages;
211 /* zero pages recv through this channel */
212 uint64_t total_zero_pages;
213 /* buffers to recv */
214 struct iovec *iov;
215 /* Pages that are not zero */
216 ram_addr_t *normal;
217 /* num of non zero pages */
218 uint32_t normal_num;
219 /* Pages that are zero */
220 ram_addr_t *zero;
221 /* num of zero pages */
222 uint32_t zero_num;
223 /* used for de-compression methods */
224 void *compress_data;
225 } MultiFDRecvParams;
226
227 typedef struct {
228 /* Setup for sending side */
229 int (*send_setup)(MultiFDSendParams *p, Error **errp);
230 /* Cleanup for sending side */
231 void (*send_cleanup)(MultiFDSendParams *p, Error **errp);
232 /* Prepare the send packet */
233 int (*send_prepare)(MultiFDSendParams *p, Error **errp);
234 /* Setup for receiving side */
235 int (*recv_setup)(MultiFDRecvParams *p, Error **errp);
236 /* Cleanup for receiving side */
237 void (*recv_cleanup)(MultiFDRecvParams *p);
238 /* Read all data */
239 int (*recv)(MultiFDRecvParams *p, Error **errp);
240 } MultiFDMethods;
241
242 void multifd_register_ops(int method, MultiFDMethods *ops);
243 void multifd_send_fill_packet(MultiFDSendParams *p);
244 bool multifd_send_prepare_common(MultiFDSendParams *p);
245 void multifd_send_zero_page_detect(MultiFDSendParams *p);
246 void multifd_recv_zero_page_process(MultiFDRecvParams *p);
247
multifd_send_prepare_header(MultiFDSendParams * p)248 static inline void multifd_send_prepare_header(MultiFDSendParams *p)
249 {
250 p->iov[0].iov_len = p->packet_len;
251 p->iov[0].iov_base = p->packet;
252 p->iovs_num++;
253 }
254
255 void multifd_channel_connect(MultiFDSendParams *p, QIOChannel *ioc);
256
257 #endif
258