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 #include <stdint.h>
  29
  30 /* This function writes a chunk of data to a file at the given position.
  31  * The pos argument can be ignored if the file is only being used for
  32  * streaming.  The handler should try to write all of the data it can.
  33  */
  34 typedef int (QEMUFilePutBufferFunc)(void *opaque, const uint8_t *buf,
  35                                     int64_t pos, int 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 int (QEMUFileGetBufferFunc)(void *opaque, uint8_t *buf,
  42                                     int64_t pos, int 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 /*
  58  * This function writes an iovec to file.
  59  */
  60 typedef ssize_t (QEMUFileWritevBufferFunc)(void *opaque, struct iovec *iov,
  61                                            int iovcnt, int64_t pos);
  62
  63 /*
  64  * This function provides hooks around different
  65  * stages of RAM migration.
  66  */
  67 typedef int (QEMURamHookFunc)(QEMUFile *f, void *opaque, uint64_t flags);
  68
  69 /*
  70  * Constants used by ram_control_* hooks
  71  */
  72 #define RAM_CONTROL_SETUP    0
  73 #define RAM_CONTROL_ROUND    1
  74 #define RAM_CONTROL_HOOK     2
  75 #define RAM_CONTROL_FINISH   3
  76
  77 /*
  78  * This function allows override of where the RAM page
  79  * is saved (such as RDMA, for example.)
  80  */
  81 typedef size_t (QEMURamSaveFunc)(QEMUFile *f, void *opaque,
  82                                ram_addr_t block_offset,
  83                                ram_addr_t offset,
  84                                size_t size,
  85                                int *bytes_sent);
  86
  87 typedef struct QEMUFileOps {
  88     QEMUFilePutBufferFunc *put_buffer;
  89     QEMUFileGetBufferFunc *get_buffer;
  90     QEMUFileCloseFunc *close;
  91     QEMUFileGetFD *get_fd;
  92     QEMUFileWritevBufferFunc *writev_buffer;
  93     QEMURamHookFunc *before_ram_iterate;
  94     QEMURamHookFunc *after_ram_iterate;
  95     QEMURamHookFunc *hook_ram_load;
  96     QEMURamSaveFunc *save_page;
  97 } QEMUFileOps;
  98
  99 struct QEMUSizedBuffer {
 100     struct iovec *iov;
 101     size_t n_iov;
 102     size_t size; /* total allocated size in all iov's */
 103     size_t used; /* number of used bytes */
 104 };
 105
 106 QEMUFile *qemu_fopen_ops(void *opaque, const QEMUFileOps *ops);
 107 QEMUFile *qemu_fopen(const char *filename, const char *mode);
 108 QEMUFile *qemu_fdopen(int fd, const char *mode);
 109 QEMUFile *qemu_fopen_socket(int fd, const char *mode);
 110 QEMUFile *qemu_popen_cmd(const char *command, const char *mode);
 111 QEMUFile *qemu_bufopen(const char *mode, QEMUSizedBuffer *input);
 112 int qemu_get_fd(QEMUFile *f);
 113 int qemu_fclose(QEMUFile *f);
 114 int64_t qemu_ftell(QEMUFile *f);
 115 void qemu_put_buffer(QEMUFile *f, const uint8_t *buf, int size);
 116 void qemu_put_byte(QEMUFile *f, int v);
 117 /*
 118  * put_buffer without copying the buffer.
 119  * The buffer should be available till it is sent asynchronously.
 120  */
 121 void qemu_put_buffer_async(QEMUFile *f, const uint8_t *buf, int size);
 122 bool qemu_file_mode_is_not_valid(const char *mode);
 123
 124 QEMUSizedBuffer *qsb_create(const uint8_t *buffer, size_t len);
 125 QEMUSizedBuffer *qsb_clone(const QEMUSizedBuffer *);
 126 void qsb_free(QEMUSizedBuffer *);
 127 size_t qsb_set_length(QEMUSizedBuffer *qsb, size_t length);
 128 size_t qsb_get_length(const QEMUSizedBuffer *qsb);
 129 ssize_t qsb_get_buffer(const QEMUSizedBuffer *, off_t start, size_t count,
 130                        uint8_t *buf);
 131 ssize_t qsb_write_at(QEMUSizedBuffer *qsb, const uint8_t *buf,
 132                      off_t pos, size_t count);
 133
 134
 135 /*
 136  * For use on files opened with qemu_bufopen
 137  */
 138 const QEMUSizedBuffer *qemu_buf_get(QEMUFile *f);
 139
 140 static inline void qemu_put_ubyte(QEMUFile *f, unsigned int v)
 141 {
 142     qemu_put_byte(f, (int)v);
 143 }
 144
 145 #define qemu_put_sbyte qemu_put_byte
 146
 147 void qemu_put_be16(QEMUFile *f, unsigned int v);
 148 void qemu_put_be32(QEMUFile *f, unsigned int v);
 149 void qemu_put_be64(QEMUFile *f, uint64_t v);
 150 int qemu_peek_buffer(QEMUFile *f, uint8_t *buf, int size, size_t offset);
 151 int qemu_get_buffer(QEMUFile *f, uint8_t *buf, int size);
 152 /*
 153  * Note that you can only peek continuous bytes from where the current pointer
 154  * is; you aren't guaranteed to be able to peak to +n bytes unless you've
 155  * previously peeked +n-1.
 156  */
 157 int qemu_peek_byte(QEMUFile *f, int offset);
 158 int qemu_get_byte(QEMUFile *f);
 159 void qemu_file_skip(QEMUFile *f, int size);
 160 void qemu_update_position(QEMUFile *f, size_t size);
 161
 162 static inline unsigned int qemu_get_ubyte(QEMUFile *f)
 163 {
 164     return (unsigned int)qemu_get_byte(f);
 165 }
 166
 167 #define qemu_get_sbyte qemu_get_byte
 168
 169 unsigned int qemu_get_be16(QEMUFile *f);
 170 unsigned int qemu_get_be32(QEMUFile *f);
 171 uint64_t qemu_get_be64(QEMUFile *f);
 172
 173 int qemu_file_rate_limit(QEMUFile *f);
 174 void qemu_file_reset_rate_limit(QEMUFile *f);
 175 void qemu_file_set_rate_limit(QEMUFile *f, int64_t new_rate);
 176 int64_t qemu_file_get_rate_limit(QEMUFile *f);
 177 int qemu_file_get_error(QEMUFile *f);
 178 void qemu_file_set_error(QEMUFile *f, int ret);
 179 void qemu_fflush(QEMUFile *f);
 180
 181 static inline void qemu_put_be64s(QEMUFile *f, const uint64_t *pv)
 182 {
 183     qemu_put_be64(f, *pv);
 184 }
 185
 186 static inline void qemu_put_be32s(QEMUFile *f, const uint32_t *pv)
 187 {
 188     qemu_put_be32(f, *pv);
 189 }
 190
 191 static inline void qemu_put_be16s(QEMUFile *f, const uint16_t *pv)
 192 {
 193     qemu_put_be16(f, *pv);
 194 }
 195
 196 static inline void qemu_put_8s(QEMUFile *f, const uint8_t *pv)
 197 {
 198     qemu_put_byte(f, *pv);
 199 }
 200
 201 static inline void qemu_get_be64s(QEMUFile *f, uint64_t *pv)
 202 {
 203     *pv = qemu_get_be64(f);
 204 }
 205
 206 static inline void qemu_get_be32s(QEMUFile *f, uint32_t *pv)
 207 {
 208     *pv = qemu_get_be32(f);
 209 }
 210
 211 static inline void qemu_get_be16s(QEMUFile *f, uint16_t *pv)
 212 {
 213     *pv = qemu_get_be16(f);
 214 }
 215
 216 static inline void qemu_get_8s(QEMUFile *f, uint8_t *pv)
 217 {
 218     *pv = qemu_get_byte(f);
 219 }
 220
 221 // Signed versions for type safety
 222 static inline void qemu_put_sbuffer(QEMUFile *f, const int8_t *buf, int size)
 223 {
 224     qemu_put_buffer(f, (const uint8_t *)buf, size);
 225 }
 226
 227 static inline void qemu_put_sbe16(QEMUFile *f, int v)
 228 {
 229     qemu_put_be16(f, (unsigned int)v);
 230 }
 231
 232 static inline void qemu_put_sbe32(QEMUFile *f, int v)
 233 {
 234     qemu_put_be32(f, (unsigned int)v);
 235 }
 236
 237 static inline void qemu_put_sbe64(QEMUFile *f, int64_t v)
 238 {
 239     qemu_put_be64(f, (uint64_t)v);
 240 }
 241
 242 static inline size_t qemu_get_sbuffer(QEMUFile *f, int8_t *buf, int size)
 243 {
 244     return qemu_get_buffer(f, (uint8_t *)buf, size);
 245 }
 246
 247 static inline int qemu_get_sbe16(QEMUFile *f)
 248 {
 249     return (int)qemu_get_be16(f);
 250 }
 251
 252 static inline int qemu_get_sbe32(QEMUFile *f)
 253 {
 254     return (int)qemu_get_be32(f);
 255 }
 256
 257 static inline int64_t qemu_get_sbe64(QEMUFile *f)
 258 {
 259     return (int64_t)qemu_get_be64(f);
 260 }
 261
 262 static inline void qemu_put_s8s(QEMUFile *f, const int8_t *pv)
 263 {
 264     qemu_put_8s(f, (const uint8_t *)pv);
 265 }
 266
 267 static inline void qemu_put_sbe16s(QEMUFile *f, const int16_t *pv)
 268 {
 269     qemu_put_be16s(f, (const uint16_t *)pv);
 270 }
 271
 272 static inline void qemu_put_sbe32s(QEMUFile *f, const int32_t *pv)
 273 {
 274     qemu_put_be32s(f, (const uint32_t *)pv);
 275 }
 276
 277 static inline void qemu_put_sbe64s(QEMUFile *f, const int64_t *pv)
 278 {
 279     qemu_put_be64s(f, (const uint64_t *)pv);
 280 }
 281
 282 static inline void qemu_get_s8s(QEMUFile *f, int8_t *pv)
 283 {
 284     qemu_get_8s(f, (uint8_t *)pv);
 285 }
 286
 287 static inline void qemu_get_sbe16s(QEMUFile *f, int16_t *pv)
 288 {
 289     qemu_get_be16s(f, (uint16_t *)pv);
 290 }
 291
 292 static inline void qemu_get_sbe32s(QEMUFile *f, int32_t *pv)
 293 {
 294     qemu_get_be32s(f, (uint32_t *)pv);
 295 }
 296
 297 static inline void qemu_get_sbe64s(QEMUFile *f, int64_t *pv)
 298 {
 299     qemu_get_be64s(f, (uint64_t *)pv);
 300 }
 301 #endif