xref: /openbmc/qemu/migration/qemu-file.h (revision 56c39a41adadfc567e1ac22089670bfde6b35365)
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
159