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
  25 #ifndef MIGRATION_QEMU_FILE_H
  26 #define MIGRATION_QEMU_FILE_H
  27
  28 #include <zlib.h>
  29 #include "exec/cpu-common.h"
  30 #include "io/channel.h"
  31
  32 /*
  33  * This function provides hooks around different
  34  * stages of RAM migration.
  35  * 'data' is call specific data associated with the 'flags' value
  36  */
  37 typedef int (QEMURamHookFunc)(QEMUFile *f, uint64_t flags, void *data);
  38
  39 /*
  40  * Constants used by ram_control_* hooks
  41  */
  42 #define RAM_CONTROL_SETUP     0
  43 #define RAM_CONTROL_ROUND     1
  44 #define RAM_CONTROL_HOOK      2
  45 #define RAM_CONTROL_FINISH    3
  46 #define RAM_CONTROL_BLOCK_REG 4
  47
  48 /*
  49  * This function allows override of where the RAM page
  50  * is saved (such as RDMA, for example.)
  51  */
  52 typedef size_t (QEMURamSaveFunc)(QEMUFile *f,
  53                                  ram_addr_t block_offset,
  54                                  ram_addr_t offset,
  55                                  size_t size,
  56                                  uint64_t *bytes_sent);
  57
  58 /*
  59  * Return a QEMUFile for comms in the opposite direction
  60  */
  61 typedef QEMUFile *(QEMURetPathFunc)(void *opaque);
  62
  63 typedef struct QEMUFileOps {
  64     QEMURetPathFunc *get_return_path;
  65 } QEMUFileOps;
  66
  67 typedef struct QEMUFileHooks {
  68     QEMURamHookFunc *before_ram_iterate;
  69     QEMURamHookFunc *after_ram_iterate;
  70     QEMURamHookFunc *hook_ram_load;
  71     QEMURamSaveFunc *save_page;
  72 } QEMUFileHooks;
  73
  74 QEMUFile *qemu_file_new_input(QIOChannel *ioc, const QEMUFileOps *ops);
  75 QEMUFile *qemu_file_new_output(QIOChannel *ioc, const QEMUFileOps *ops);
  76 void qemu_file_set_hooks(QEMUFile *f, const QEMUFileHooks *hooks);
  77 int qemu_fclose(QEMUFile *f);
  78
  79 /*
  80  * qemu_file_total_transferred:
  81  *
  82  * Report the total number of bytes transferred with
  83  * this file.
  84  *
  85  * For writable files, any pending buffers will be
  86  * flushed, so the reported value will be equal to
  87  * the number of bytes transferred on the wire.
  88  *
  89  * For readable files, the reported value will be
  90  * equal to the number of bytes transferred on the
  91  * wire.
  92  *
  93  * Returns: the total bytes transferred
  94  */
  95 int64_t qemu_file_total_transferred(QEMUFile *f);
  96
  97 /*
  98  * qemu_file_total_transferred_fast:
  99  *
 100  * As qemu_file_total_transferred except for writable
 101  * files, where no flush is performed and the reported
 102  * amount will include the size of any queued buffers,
 103  * on top of the amount actually transferred.
 104  *
 105  * Returns: the total bytes transferred and queued
 106  */
 107 int64_t qemu_file_total_transferred_fast(QEMUFile *f);
 108
 109 /*
 110  * put_buffer without copying the buffer.
 111  * The buffer should be available till it is sent asynchronously.
 112  */
 113 void qemu_put_buffer_async(QEMUFile *f, const uint8_t *buf, size_t size,
 114                            bool may_free);
 115 bool qemu_file_mode_is_not_valid(const char *mode);
 116 bool qemu_file_is_writable(QEMUFile *f);
 117
 118 #include "migration/qemu-file-types.h"
 119
 120 size_t qemu_peek_buffer(QEMUFile *f, uint8_t **buf, size_t size, size_t offset);
 121 size_t qemu_get_buffer_in_place(QEMUFile *f, uint8_t **buf, size_t size);
 122 ssize_t qemu_put_compression_data(QEMUFile *f, z_stream *stream,
 123                                   const uint8_t *p, size_t size);
 124 int qemu_put_qemu_file(QEMUFile *f_des, QEMUFile *f_src);
 125
 126 /*
 127  * Note that you can only peek continuous bytes from where the current pointer
 128  * is; you aren't guaranteed to be able to peak to +n bytes unless you've
 129  * previously peeked +n-1.
 130  */
 131 int qemu_peek_byte(QEMUFile *f, int offset);
 132 void qemu_file_skip(QEMUFile *f, int size);
 133 /*
 134  * qemu_file_credit_transfer:
 135  *
 136  * Report on a number of bytes that have been transferred
 137  * out of band from the main file object I/O methods. This
 138  * accounting information tracks the total migration traffic.
 139  */
 140 void qemu_file_credit_transfer(QEMUFile *f, size_t size);
 141 void qemu_file_reset_rate_limit(QEMUFile *f);
 142 /*
 143  * qemu_file_acct_rate_limit:
 144  *
 145  * Report on a number of bytes the have been transferred
 146  * out of band from the main file object I/O methods, and
 147  * need to be applied to the rate limiting calcuations
 148  */
 149 void qemu_file_acct_rate_limit(QEMUFile *f, int64_t len);
 150 void qemu_file_set_rate_limit(QEMUFile *f, int64_t new_rate);
 151 int64_t qemu_file_get_rate_limit(QEMUFile *f);
 152 int qemu_file_get_error_obj(QEMUFile *f, Error **errp);
 153 void qemu_file_set_error_obj(QEMUFile *f, int ret, Error *err);
 154 void qemu_file_set_error(QEMUFile *f, int ret);
 155 int qemu_file_shutdown(QEMUFile *f);
 156 QEMUFile *qemu_file_get_return_path(QEMUFile *f);
 157 void qemu_fflush(QEMUFile *f);
 158 void qemu_file_set_blocking(QEMUFile *f, bool block);
 159
 160 void ram_control_before_iterate(QEMUFile *f, uint64_t flags);
 161 void ram_control_after_iterate(QEMUFile *f, uint64_t flags);
 162 void ram_control_load_hook(QEMUFile *f, uint64_t flags, void *data);
 163
 164 /* Whenever this is found in the data stream, the flags
 165  * will be passed to ram_control_load_hook in the incoming-migration
 166  * side. This lets before_ram_iterate/after_ram_iterate add
 167  * transport-specific sections to the RAM migration data.
 168  */
 169 #define RAM_SAVE_FLAG_HOOK     0x80
 170
 171 #define RAM_SAVE_CONTROL_NOT_SUPP -1000
 172 #define RAM_SAVE_CONTROL_DELAYED  -2000
 173
 174 size_t ram_control_save_page(QEMUFile *f, ram_addr_t block_offset,
 175                              ram_addr_t offset, size_t size,
 176                              uint64_t *bytes_sent);
 177 QIOChannel *qemu_file_get_ioc(QEMUFile *file);
 178
 179 #endif