xref: /openbmc/qemu/migration/qemu-file.h (revision beb1a917)
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