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 typedef struct QEMUFileHooks {
  59     QEMURamHookFunc *before_ram_iterate;
  60     QEMURamHookFunc *after_ram_iterate;
  61     QEMURamHookFunc *hook_ram_load;
  62     QEMURamSaveFunc *save_page;
  63 } QEMUFileHooks;
  64
  65 QEMUFile *qemu_file_new_input(QIOChannel *ioc);
  66 QEMUFile *qemu_file_new_output(QIOChannel *ioc);
  67 void qemu_file_set_hooks(QEMUFile *f, const QEMUFileHooks *hooks);
  68 int qemu_fclose(QEMUFile *f);
  69
  70 /*
  71  * qemu_file_transferred:
  72  *
  73  * Report the total number of bytes transferred with
  74  * this file.
  75  *
  76  * For writable files, any pending buffers will be
  77  * flushed, so the reported value will be equal to
  78  * the number of bytes transferred on the wire.
  79  *
  80  * For readable files, the reported value will be
  81  * equal to the number of bytes transferred on the
  82  * wire.
  83  *
  84  * Returns: the total bytes transferred
  85  */
  86 uint64_t qemu_file_transferred(QEMUFile *f);
  87
  88 /*
  89  * qemu_file_transferred_noflush:
  90  *
  91  * As qemu_file_transferred except for writable files, where no flush
  92  * is performed and the reported amount will include the size of any
  93  * queued buffers, on top of the amount actually transferred.
  94  *
  95  * Returns: the total bytes transferred and queued
  96  */
  97 uint64_t qemu_file_transferred_noflush(QEMUFile *f);
  98
  99 /*
 100  * put_buffer without copying the buffer.
 101  * The buffer should be available till it is sent asynchronously.
 102  */
 103 void qemu_put_buffer_async(QEMUFile *f, const uint8_t *buf, size_t size,
 104                            bool may_free);
 105
 106 #include "migration/qemu-file-types.h"
 107
 108 size_t coroutine_mixed_fn qemu_peek_buffer(QEMUFile *f, uint8_t **buf, size_t size, size_t offset);
 109 size_t coroutine_mixed_fn qemu_get_buffer_in_place(QEMUFile *f, uint8_t **buf, size_t size);
 110 ssize_t qemu_put_compression_data(QEMUFile *f, z_stream *stream,
 111                                   const uint8_t *p, size_t size);
 112 int qemu_put_qemu_file(QEMUFile *f_des, QEMUFile *f_src);
 113 bool qemu_file_buffer_empty(QEMUFile *file);
 114
 115 /*
 116  * Note that you can only peek continuous bytes from where the current pointer
 117  * is; you aren't guaranteed to be able to peak to +n bytes unless you've
 118  * previously peeked +n-1.
 119  */
 120 int coroutine_mixed_fn qemu_peek_byte(QEMUFile *f, int offset);
 121 void qemu_file_skip(QEMUFile *f, int size);
 122 /*
 123  * qemu_file_credit_transfer:
 124  *
 125  * Report on a number of bytes that have been transferred
 126  * out of band from the main file object I/O methods. This
 127  * accounting information tracks the total migration traffic.
 128  */
 129 void qemu_file_credit_transfer(QEMUFile *f, size_t size);
 130 int qemu_file_get_error_obj_any(QEMUFile *f1, QEMUFile *f2, Error **errp);
 131 void qemu_file_set_error_obj(QEMUFile *f, int ret, Error *err);
 132 void qemu_file_set_error(QEMUFile *f, int ret);
 133 int qemu_file_shutdown(QEMUFile *f);
 134 QEMUFile *qemu_file_get_return_path(QEMUFile *f);
 135 void qemu_fflush(QEMUFile *f);
 136 void qemu_file_set_blocking(QEMUFile *f, bool block);
 137 int qemu_file_get_to_fd(QEMUFile *f, int fd, size_t size);
 138
 139 void ram_control_before_iterate(QEMUFile *f, uint64_t flags);
 140 void ram_control_after_iterate(QEMUFile *f, uint64_t flags);
 141 void ram_control_load_hook(QEMUFile *f, uint64_t flags, void *data);
 142
 143 /* Whenever this is found in the data stream, the flags
 144  * will be passed to ram_control_load_hook in the incoming-migration
 145  * side. This lets before_ram_iterate/after_ram_iterate add
 146  * transport-specific sections to the RAM migration data.
 147  */
 148 #define RAM_SAVE_FLAG_HOOK     0x80
 149
 150 #define RAM_SAVE_CONTROL_NOT_SUPP -1000
 151 #define RAM_SAVE_CONTROL_DELAYED  -2000
 152
 153 size_t ram_control_save_page(QEMUFile *f, ram_addr_t block_offset,
 154                              ram_addr_t offset, size_t size,
 155                              uint64_t *bytes_sent);
 156 QIOChannel *qemu_file_get_ioc(QEMUFile *file);
 157
 158 #endif