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 /*
  88  * Stop any read or write (depending on flags) on the underlying
  89  * transport on the QEMUFile.
  90  * Existing blocking reads/writes must be woken
  91  * Returns 0 on success, -err on error
  92  */
  93 typedef int (QEMUFileShutdownFunc)(void *opaque, bool rd, bool wr);
  94
  95 typedef struct QEMUFileOps {
  96     QEMUFilePutBufferFunc *put_buffer;
  97     QEMUFileGetBufferFunc *get_buffer;
  98     QEMUFileCloseFunc *close;
  99     QEMUFileGetFD *get_fd;
 100     QEMUFileWritevBufferFunc *writev_buffer;
 101     QEMURamHookFunc *before_ram_iterate;
 102     QEMURamHookFunc *after_ram_iterate;
 103     QEMURamHookFunc *hook_ram_load;
 104     QEMURamSaveFunc *save_page;
 105     QEMUFileShutdownFunc *shut_down;
 106 } QEMUFileOps;
 107
 108 struct QEMUSizedBuffer {
 109     struct iovec *iov;
 110     size_t n_iov;
 111     size_t size; /* total allocated size in all iov's */
 112     size_t used; /* number of used bytes */
 113 };
 114
 115 QEMUFile *qemu_fopen_ops(void *opaque, const QEMUFileOps *ops);
 116 QEMUFile *qemu_fopen(const char *filename, const char *mode);
 117 QEMUFile *qemu_fdopen(int fd, const char *mode);
 118 QEMUFile *qemu_fopen_socket(int fd, const char *mode);
 119 QEMUFile *qemu_popen_cmd(const char *command, const char *mode);
 120 QEMUFile *qemu_bufopen(const char *mode, QEMUSizedBuffer *input);
 121 int qemu_get_fd(QEMUFile *f);
 122 int qemu_fclose(QEMUFile *f);
 123 int64_t qemu_ftell(QEMUFile *f);
 124 int64_t qemu_ftell_fast(QEMUFile *f);
 125 void qemu_put_buffer(QEMUFile *f, const uint8_t *buf, int size);
 126 void qemu_put_byte(QEMUFile *f, int v);
 127 /*
 128  * put_buffer without copying the buffer.
 129  * The buffer should be available till it is sent asynchronously.
 130  */
 131 void qemu_put_buffer_async(QEMUFile *f, const uint8_t *buf, int size);
 132 bool qemu_file_mode_is_not_valid(const char *mode);
 133 bool qemu_file_is_writable(QEMUFile *f);
 134
 135 QEMUSizedBuffer *qsb_create(const uint8_t *buffer, size_t len);
 136 QEMUSizedBuffer *qsb_clone(const QEMUSizedBuffer *);
 137 void qsb_free(QEMUSizedBuffer *);
 138 size_t qsb_set_length(QEMUSizedBuffer *qsb, size_t length);
 139 size_t qsb_get_length(const QEMUSizedBuffer *qsb);
 140 ssize_t qsb_get_buffer(const QEMUSizedBuffer *, off_t start, size_t count,
 141                        uint8_t *buf);
 142 ssize_t qsb_write_at(QEMUSizedBuffer *qsb, const uint8_t *buf,
 143                      off_t pos, size_t count);
 144
 145
 146 /*
 147  * For use on files opened with qemu_bufopen
 148  */
 149 const QEMUSizedBuffer *qemu_buf_get(QEMUFile *f);
 150
 151 static inline void qemu_put_ubyte(QEMUFile *f, unsigned int v)
 152 {
 153     qemu_put_byte(f, (int)v);
 154 }
 155
 156 #define qemu_put_sbyte qemu_put_byte
 157
 158 void qemu_put_be16(QEMUFile *f, unsigned int v);
 159 void qemu_put_be32(QEMUFile *f, unsigned int v);
 160 void qemu_put_be64(QEMUFile *f, uint64_t v);
 161 int qemu_peek_buffer(QEMUFile *f, uint8_t *buf, int size, size_t offset);
 162 int qemu_get_buffer(QEMUFile *f, uint8_t *buf, int size);
 163 /*
 164  * Note that you can only peek continuous bytes from where the current pointer
 165  * is; you aren't guaranteed to be able to peak to +n bytes unless you've
 166  * previously peeked +n-1.
 167  */
 168 int qemu_peek_byte(QEMUFile *f, int offset);
 169 int qemu_get_byte(QEMUFile *f);
 170 void qemu_file_skip(QEMUFile *f, int size);
 171 void qemu_update_position(QEMUFile *f, size_t size);
 172
 173 static inline unsigned int qemu_get_ubyte(QEMUFile *f)
 174 {
 175     return (unsigned int)qemu_get_byte(f);
 176 }
 177
 178 #define qemu_get_sbyte qemu_get_byte
 179
 180 unsigned int qemu_get_be16(QEMUFile *f);
 181 unsigned int qemu_get_be32(QEMUFile *f);
 182 uint64_t qemu_get_be64(QEMUFile *f);
 183
 184 int qemu_file_rate_limit(QEMUFile *f);
 185 void qemu_file_reset_rate_limit(QEMUFile *f);
 186 void qemu_file_set_rate_limit(QEMUFile *f, int64_t new_rate);
 187 int64_t qemu_file_get_rate_limit(QEMUFile *f);
 188 int qemu_file_get_error(QEMUFile *f);
 189 void qemu_file_set_error(QEMUFile *f, int ret);
 190 int qemu_file_shutdown(QEMUFile *f);
 191 void qemu_fflush(QEMUFile *f);
 192
 193 static inline void qemu_put_be64s(QEMUFile *f, const uint64_t *pv)
 194 {
 195     qemu_put_be64(f, *pv);
 196 }
 197
 198 static inline void qemu_put_be32s(QEMUFile *f, const uint32_t *pv)
 199 {
 200     qemu_put_be32(f, *pv);
 201 }
 202
 203 static inline void qemu_put_be16s(QEMUFile *f, const uint16_t *pv)
 204 {
 205     qemu_put_be16(f, *pv);
 206 }
 207
 208 static inline void qemu_put_8s(QEMUFile *f, const uint8_t *pv)
 209 {
 210     qemu_put_byte(f, *pv);
 211 }
 212
 213 static inline void qemu_get_be64s(QEMUFile *f, uint64_t *pv)
 214 {
 215     *pv = qemu_get_be64(f);
 216 }
 217
 218 static inline void qemu_get_be32s(QEMUFile *f, uint32_t *pv)
 219 {
 220     *pv = qemu_get_be32(f);
 221 }
 222
 223 static inline void qemu_get_be16s(QEMUFile *f, uint16_t *pv)
 224 {
 225     *pv = qemu_get_be16(f);
 226 }
 227
 228 static inline void qemu_get_8s(QEMUFile *f, uint8_t *pv)
 229 {
 230     *pv = qemu_get_byte(f);
 231 }
 232
 233 // Signed versions for type safety
 234 static inline void qemu_put_sbuffer(QEMUFile *f, const int8_t *buf, int size)
 235 {
 236     qemu_put_buffer(f, (const uint8_t *)buf, size);
 237 }
 238
 239 static inline void qemu_put_sbe16(QEMUFile *f, int v)
 240 {
 241     qemu_put_be16(f, (unsigned int)v);
 242 }
 243
 244 static inline void qemu_put_sbe32(QEMUFile *f, int v)
 245 {
 246     qemu_put_be32(f, (unsigned int)v);
 247 }
 248
 249 static inline void qemu_put_sbe64(QEMUFile *f, int64_t v)
 250 {
 251     qemu_put_be64(f, (uint64_t)v);
 252 }
 253
 254 static inline size_t qemu_get_sbuffer(QEMUFile *f, int8_t *buf, int size)
 255 {
 256     return qemu_get_buffer(f, (uint8_t *)buf, size);
 257 }
 258
 259 static inline int qemu_get_sbe16(QEMUFile *f)
 260 {
 261     return (int)qemu_get_be16(f);
 262 }
 263
 264 static inline int qemu_get_sbe32(QEMUFile *f)
 265 {
 266     return (int)qemu_get_be32(f);
 267 }
 268
 269 static inline int64_t qemu_get_sbe64(QEMUFile *f)
 270 {
 271     return (int64_t)qemu_get_be64(f);
 272 }
 273
 274 static inline void qemu_put_s8s(QEMUFile *f, const int8_t *pv)
 275 {
 276     qemu_put_8s(f, (const uint8_t *)pv);
 277 }
 278
 279 static inline void qemu_put_sbe16s(QEMUFile *f, const int16_t *pv)
 280 {
 281     qemu_put_be16s(f, (const uint16_t *)pv);
 282 }
 283
 284 static inline void qemu_put_sbe32s(QEMUFile *f, const int32_t *pv)
 285 {
 286     qemu_put_be32s(f, (const uint32_t *)pv);
 287 }
 288
 289 static inline void qemu_put_sbe64s(QEMUFile *f, const int64_t *pv)
 290 {
 291     qemu_put_be64s(f, (const uint64_t *)pv);
 292 }
 293
 294 static inline void qemu_get_s8s(QEMUFile *f, int8_t *pv)
 295 {
 296     qemu_get_8s(f, (uint8_t *)pv);
 297 }
 298
 299 static inline void qemu_get_sbe16s(QEMUFile *f, int16_t *pv)
 300 {
 301     qemu_get_be16s(f, (uint16_t *)pv);
 302 }
 303
 304 static inline void qemu_get_sbe32s(QEMUFile *f, int32_t *pv)
 305 {
 306     qemu_get_be32s(f, (uint32_t *)pv);
 307 }
 308
 309 static inline void qemu_get_sbe64s(QEMUFile *f, int64_t *pv)
 310 {
 311     qemu_get_be64s(f, (uint64_t *)pv);
 312 }
 313 #endif