migration: introduce set_blocking function in QEMUFileOps
[qemu.git] / include / migration / qemu-file.h
1 /*
2 * QEMU System Emulator
3 *
4 * Copyright (c) 2003-2008 Fabrice Bellard
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to deal
8 * in the Software without restriction, including without limitation the rights
9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 * copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22 * THE SOFTWARE.
23 */
24 #ifndef QEMU_FILE_H
25 #define QEMU_FILE_H 1
26 #include "exec/cpu-common.h"
27
28
29 /* This function writes a chunk of data to a file at the given position.
30 * The pos argument can be ignored if the file is only being used for
31 * streaming. The handler must write all of the data or return a negative
32 * errno value.
33 */
34 typedef ssize_t (QEMUFilePutBufferFunc)(void *opaque, const uint8_t *buf,
35 int64_t pos, size_t size);
36
37 /* Read a chunk of data from a file at the given position. The pos argument
38 * can be ignored if the file is only be used for streaming. The number of
39 * bytes actually read should be returned.
40 */
41 typedef ssize_t (QEMUFileGetBufferFunc)(void *opaque, uint8_t *buf,
42 int64_t pos, size_t size);
43
44 /* Close a file
45 *
46 * Return negative error number on error, 0 or positive value on success.
47 *
48 * The meaning of return value on success depends on the specific back-end being
49 * used.
50 */
51 typedef int (QEMUFileCloseFunc)(void *opaque);
52
53 /* Called to return the OS file descriptor associated to the QEMUFile.
54 */
55 typedef int (QEMUFileGetFD)(void *opaque);
56
57 /* Called to change the blocking mode of the file
58 */
59 typedef int (QEMUFileSetBlocking)(void *opaque, bool enabled);
60
61 /*
62 * This function writes an iovec to file. The handler must write all
63 * of the data or return a negative errno value.
64 */
65 typedef ssize_t (QEMUFileWritevBufferFunc)(void *opaque, struct iovec *iov,
66 int iovcnt, int64_t pos);
67
68 /*
69 * This function provides hooks around different
70 * stages of RAM migration.
71 * 'opaque' is the backend specific data in QEMUFile
72 * 'data' is call specific data associated with the 'flags' value
73 */
74 typedef int (QEMURamHookFunc)(QEMUFile *f, void *opaque, uint64_t flags,
75 void *data);
76
77 /*
78 * Constants used by ram_control_* hooks
79 */
80 #define RAM_CONTROL_SETUP 0
81 #define RAM_CONTROL_ROUND 1
82 #define RAM_CONTROL_HOOK 2
83 #define RAM_CONTROL_FINISH 3
84 #define RAM_CONTROL_BLOCK_REG 4
85
86 /*
87 * This function allows override of where the RAM page
88 * is saved (such as RDMA, for example.)
89 */
90 typedef size_t (QEMURamSaveFunc)(QEMUFile *f, void *opaque,
91 ram_addr_t block_offset,
92 ram_addr_t offset,
93 size_t size,
94 uint64_t *bytes_sent);
95
96 /*
97 * Return a QEMUFile for comms in the opposite direction
98 */
99 typedef QEMUFile *(QEMURetPathFunc)(void *opaque);
100
101 /*
102 * Stop any read or write (depending on flags) on the underlying
103 * transport on the QEMUFile.
104 * Existing blocking reads/writes must be woken
105 * Returns 0 on success, -err on error
106 */
107 typedef int (QEMUFileShutdownFunc)(void *opaque, bool rd, bool wr);
108
109 typedef struct QEMUFileOps {
110 QEMUFilePutBufferFunc *put_buffer;
111 QEMUFileGetBufferFunc *get_buffer;
112 QEMUFileCloseFunc *close;
113 QEMUFileGetFD *get_fd;
114 QEMUFileSetBlocking *set_blocking;
115 QEMUFileWritevBufferFunc *writev_buffer;
116 QEMURetPathFunc *get_return_path;
117 QEMUFileShutdownFunc *shut_down;
118 } QEMUFileOps;
119
120 typedef struct QEMUFileHooks {
121 QEMURamHookFunc *before_ram_iterate;
122 QEMURamHookFunc *after_ram_iterate;
123 QEMURamHookFunc *hook_ram_load;
124 QEMURamSaveFunc *save_page;
125 } QEMUFileHooks;
126
127 struct QEMUSizedBuffer {
128 struct iovec *iov;
129 size_t n_iov;
130 size_t size; /* total allocated size in all iov's */
131 size_t used; /* number of used bytes */
132 };
133
134 QEMUFile *qemu_fopen_ops(void *opaque, const QEMUFileOps *ops);
135 QEMUFile *qemu_fopen(const char *filename, const char *mode);
136 QEMUFile *qemu_fdopen(int fd, const char *mode);
137 QEMUFile *qemu_fopen_socket(int fd, const char *mode);
138 QEMUFile *qemu_popen_cmd(const char *command, const char *mode);
139 QEMUFile *qemu_bufopen(const char *mode, QEMUSizedBuffer *input);
140 void qemu_file_set_hooks(QEMUFile *f, const QEMUFileHooks *hooks);
141 int qemu_get_fd(QEMUFile *f);
142 int qemu_fclose(QEMUFile *f);
143 int64_t qemu_ftell(QEMUFile *f);
144 int64_t qemu_ftell_fast(QEMUFile *f);
145 void qemu_put_buffer(QEMUFile *f, const uint8_t *buf, size_t size);
146 void qemu_put_byte(QEMUFile *f, int v);
147 /*
148 * put_buffer without copying the buffer.
149 * The buffer should be available till it is sent asynchronously.
150 */
151 void qemu_put_buffer_async(QEMUFile *f, const uint8_t *buf, size_t size);
152 bool qemu_file_mode_is_not_valid(const char *mode);
153 bool qemu_file_is_writable(QEMUFile *f);
154
155 QEMUSizedBuffer *qsb_create(const uint8_t *buffer, size_t len);
156 void qsb_free(QEMUSizedBuffer *);
157 size_t qsb_set_length(QEMUSizedBuffer *qsb, size_t length);
158 size_t qsb_get_length(const QEMUSizedBuffer *qsb);
159 ssize_t qsb_get_buffer(const QEMUSizedBuffer *, off_t start, size_t count,
160 uint8_t *buf);
161 ssize_t qsb_write_at(QEMUSizedBuffer *qsb, const uint8_t *buf,
162 off_t pos, size_t count);
163
164
165 /*
166 * For use on files opened with qemu_bufopen
167 */
168 const QEMUSizedBuffer *qemu_buf_get(QEMUFile *f);
169
170 static inline void qemu_put_ubyte(QEMUFile *f, unsigned int v)
171 {
172 qemu_put_byte(f, (int)v);
173 }
174
175 #define qemu_put_sbyte qemu_put_byte
176
177 void qemu_put_be16(QEMUFile *f, unsigned int v);
178 void qemu_put_be32(QEMUFile *f, unsigned int v);
179 void qemu_put_be64(QEMUFile *f, uint64_t v);
180 size_t qemu_peek_buffer(QEMUFile *f, uint8_t **buf, size_t size, size_t offset);
181 size_t qemu_get_buffer(QEMUFile *f, uint8_t *buf, size_t size);
182 size_t qemu_get_buffer_in_place(QEMUFile *f, uint8_t **buf, size_t size);
183 ssize_t qemu_put_compression_data(QEMUFile *f, const uint8_t *p, size_t size,
184 int level);
185 int qemu_put_qemu_file(QEMUFile *f_des, QEMUFile *f_src);
186
187 /*
188 * Note that you can only peek continuous bytes from where the current pointer
189 * is; you aren't guaranteed to be able to peak to +n bytes unless you've
190 * previously peeked +n-1.
191 */
192 int qemu_peek_byte(QEMUFile *f, int offset);
193 int qemu_get_byte(QEMUFile *f);
194 void qemu_file_skip(QEMUFile *f, int size);
195 void qemu_update_position(QEMUFile *f, size_t size);
196
197 static inline unsigned int qemu_get_ubyte(QEMUFile *f)
198 {
199 return (unsigned int)qemu_get_byte(f);
200 }
201
202 #define qemu_get_sbyte qemu_get_byte
203
204 unsigned int qemu_get_be16(QEMUFile *f);
205 unsigned int qemu_get_be32(QEMUFile *f);
206 uint64_t qemu_get_be64(QEMUFile *f);
207
208 int qemu_file_rate_limit(QEMUFile *f);
209 void qemu_file_reset_rate_limit(QEMUFile *f);
210 void qemu_file_set_rate_limit(QEMUFile *f, int64_t new_rate);
211 int64_t qemu_file_get_rate_limit(QEMUFile *f);
212 int qemu_file_get_error(QEMUFile *f);
213 void qemu_file_set_error(QEMUFile *f, int ret);
214 int qemu_file_shutdown(QEMUFile *f);
215 QEMUFile *qemu_file_get_return_path(QEMUFile *f);
216 void qemu_fflush(QEMUFile *f);
217 void qemu_file_set_blocking(QEMUFile *f, bool block);
218
219 static inline void qemu_put_be64s(QEMUFile *f, const uint64_t *pv)
220 {
221 qemu_put_be64(f, *pv);
222 }
223
224 static inline void qemu_put_be32s(QEMUFile *f, const uint32_t *pv)
225 {
226 qemu_put_be32(f, *pv);
227 }
228
229 static inline void qemu_put_be16s(QEMUFile *f, const uint16_t *pv)
230 {
231 qemu_put_be16(f, *pv);
232 }
233
234 static inline void qemu_put_8s(QEMUFile *f, const uint8_t *pv)
235 {
236 qemu_put_byte(f, *pv);
237 }
238
239 static inline void qemu_get_be64s(QEMUFile *f, uint64_t *pv)
240 {
241 *pv = qemu_get_be64(f);
242 }
243
244 static inline void qemu_get_be32s(QEMUFile *f, uint32_t *pv)
245 {
246 *pv = qemu_get_be32(f);
247 }
248
249 static inline void qemu_get_be16s(QEMUFile *f, uint16_t *pv)
250 {
251 *pv = qemu_get_be16(f);
252 }
253
254 static inline void qemu_get_8s(QEMUFile *f, uint8_t *pv)
255 {
256 *pv = qemu_get_byte(f);
257 }
258
259 // Signed versions for type safety
260 static inline void qemu_put_sbuffer(QEMUFile *f, const int8_t *buf, size_t size)
261 {
262 qemu_put_buffer(f, (const uint8_t *)buf, size);
263 }
264
265 static inline void qemu_put_sbe16(QEMUFile *f, int v)
266 {
267 qemu_put_be16(f, (unsigned int)v);
268 }
269
270 static inline void qemu_put_sbe32(QEMUFile *f, int v)
271 {
272 qemu_put_be32(f, (unsigned int)v);
273 }
274
275 static inline void qemu_put_sbe64(QEMUFile *f, int64_t v)
276 {
277 qemu_put_be64(f, (uint64_t)v);
278 }
279
280 static inline size_t qemu_get_sbuffer(QEMUFile *f, int8_t *buf, int size)
281 {
282 return qemu_get_buffer(f, (uint8_t *)buf, size);
283 }
284
285 static inline int qemu_get_sbe16(QEMUFile *f)
286 {
287 return (int)qemu_get_be16(f);
288 }
289
290 static inline int qemu_get_sbe32(QEMUFile *f)
291 {
292 return (int)qemu_get_be32(f);
293 }
294
295 static inline int64_t qemu_get_sbe64(QEMUFile *f)
296 {
297 return (int64_t)qemu_get_be64(f);
298 }
299
300 static inline void qemu_put_s8s(QEMUFile *f, const int8_t *pv)
301 {
302 qemu_put_8s(f, (const uint8_t *)pv);
303 }
304
305 static inline void qemu_put_sbe16s(QEMUFile *f, const int16_t *pv)
306 {
307 qemu_put_be16s(f, (const uint16_t *)pv);
308 }
309
310 static inline void qemu_put_sbe32s(QEMUFile *f, const int32_t *pv)
311 {
312 qemu_put_be32s(f, (const uint32_t *)pv);
313 }
314
315 static inline void qemu_put_sbe64s(QEMUFile *f, const int64_t *pv)
316 {
317 qemu_put_be64s(f, (const uint64_t *)pv);
318 }
319
320 static inline void qemu_get_s8s(QEMUFile *f, int8_t *pv)
321 {
322 qemu_get_8s(f, (uint8_t *)pv);
323 }
324
325 static inline void qemu_get_sbe16s(QEMUFile *f, int16_t *pv)
326 {
327 qemu_get_be16s(f, (uint16_t *)pv);
328 }
329
330 static inline void qemu_get_sbe32s(QEMUFile *f, int32_t *pv)
331 {
332 qemu_get_be32s(f, (uint32_t *)pv);
333 }
334
335 static inline void qemu_get_sbe64s(QEMUFile *f, int64_t *pv)
336 {
337 qemu_get_be64s(f, (uint64_t *)pv);
338 }
339
340 size_t qemu_get_counted_string(QEMUFile *f, char buf[256]);
341
342 #endif