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 31 /* Read a chunk of data from a file at the given position. The pos argument 32 * can be ignored if the file is only be used for streaming. The number of 33 * bytes actually read should be returned. 34 */ 35 typedef ssize_t (QEMUFileGetBufferFunc)(void *opaque, uint8_t *buf, 36 int64_t pos, size_t size); 37 38 /* Close a file 39 * 40 * Return negative error number on error, 0 or positive value on success. 41 * 42 * The meaning of return value on success depends on the specific back-end being 43 * used. 44 */ 45 typedef int (QEMUFileCloseFunc)(void *opaque); 46 47 /* Called to return the OS file descriptor associated to the QEMUFile. 48 */ 49 typedef int (QEMUFileGetFD)(void *opaque); 50 51 /* Called to change the blocking mode of the file 52 */ 53 typedef int (QEMUFileSetBlocking)(void *opaque, bool enabled); 54 55 /* 56 * This function writes an iovec to file. The handler must write all 57 * of the data or return a negative errno value. 58 */ 59 typedef ssize_t (QEMUFileWritevBufferFunc)(void *opaque, struct iovec *iov, 60 int iovcnt, int64_t pos); 61 62 /* 63 * This function provides hooks around different 64 * stages of RAM migration. 65 * 'opaque' is the backend specific data in QEMUFile 66 * 'data' is call specific data associated with the 'flags' value 67 */ 68 typedef int (QEMURamHookFunc)(QEMUFile *f, void *opaque, uint64_t flags, 69 void *data); 70 71 /* 72 * Constants used by ram_control_* hooks 73 */ 74 #define RAM_CONTROL_SETUP 0 75 #define RAM_CONTROL_ROUND 1 76 #define RAM_CONTROL_HOOK 2 77 #define RAM_CONTROL_FINISH 3 78 #define RAM_CONTROL_BLOCK_REG 4 79 80 /* 81 * This function allows override of where the RAM page 82 * is saved (such as RDMA, for example.) 83 */ 84 typedef size_t (QEMURamSaveFunc)(QEMUFile *f, void *opaque, 85 ram_addr_t block_offset, 86 ram_addr_t offset, 87 size_t size, 88 uint64_t *bytes_sent); 89 90 /* 91 * Return a QEMUFile for comms in the opposite direction 92 */ 93 typedef QEMUFile *(QEMURetPathFunc)(void *opaque); 94 95 /* 96 * Stop any read or write (depending on flags) on the underlying 97 * transport on the QEMUFile. 98 * Existing blocking reads/writes must be woken 99 * Returns 0 on success, -err on error 100 */ 101 typedef int (QEMUFileShutdownFunc)(void *opaque, bool rd, bool wr); 102 103 typedef struct QEMUFileOps { 104 QEMUFileGetBufferFunc *get_buffer; 105 QEMUFileCloseFunc *close; 106 QEMUFileSetBlocking *set_blocking; 107 QEMUFileWritevBufferFunc *writev_buffer; 108 QEMURetPathFunc *get_return_path; 109 QEMUFileShutdownFunc *shut_down; 110 } QEMUFileOps; 111 112 typedef struct QEMUFileHooks { 113 QEMURamHookFunc *before_ram_iterate; 114 QEMURamHookFunc *after_ram_iterate; 115 QEMURamHookFunc *hook_ram_load; 116 QEMURamSaveFunc *save_page; 117 } QEMUFileHooks; 118 119 QEMUFile *qemu_fopen_ops(void *opaque, const QEMUFileOps *ops); 120 void qemu_file_set_hooks(QEMUFile *f, const QEMUFileHooks *hooks); 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 /* 126 * put_buffer without copying the buffer. 127 * The buffer should be available till it is sent asynchronously. 128 */ 129 void qemu_put_buffer_async(QEMUFile *f, const uint8_t *buf, size_t size, 130 bool may_free); 131 bool qemu_file_mode_is_not_valid(const char *mode); 132 bool qemu_file_is_writable(QEMUFile *f); 133 134 #include "migration/qemu-file-types.h" 135 136 size_t qemu_peek_buffer(QEMUFile *f, uint8_t **buf, size_t size, size_t offset); 137 size_t qemu_get_buffer_in_place(QEMUFile *f, uint8_t **buf, size_t size); 138 ssize_t qemu_put_compression_data(QEMUFile *f, z_stream *stream, 139 const uint8_t *p, size_t size); 140 int qemu_put_qemu_file(QEMUFile *f_des, QEMUFile *f_src); 141 142 /* 143 * Note that you can only peek continuous bytes from where the current pointer 144 * is; you aren't guaranteed to be able to peak to +n bytes unless you've 145 * previously peeked +n-1. 146 */ 147 int qemu_peek_byte(QEMUFile *f, int offset); 148 void qemu_file_skip(QEMUFile *f, int size); 149 void qemu_update_position(QEMUFile *f, size_t size); 150 void qemu_file_reset_rate_limit(QEMUFile *f); 151 void qemu_file_set_rate_limit(QEMUFile *f, int64_t new_rate); 152 int64_t qemu_file_get_rate_limit(QEMUFile *f); 153 void qemu_file_set_error(QEMUFile *f, int ret); 154 int qemu_file_shutdown(QEMUFile *f); 155 QEMUFile *qemu_file_get_return_path(QEMUFile *f); 156 void qemu_fflush(QEMUFile *f); 157 void qemu_file_set_blocking(QEMUFile *f, bool block); 158 159 size_t qemu_get_counted_string(QEMUFile *f, char buf[256]); 160 161 void ram_control_before_iterate(QEMUFile *f, uint64_t flags); 162 void ram_control_after_iterate(QEMUFile *f, uint64_t flags); 163 void ram_control_load_hook(QEMUFile *f, uint64_t flags, void *data); 164 165 /* Whenever this is found in the data stream, the flags 166 * will be passed to ram_control_load_hook in the incoming-migration 167 * side. This lets before_ram_iterate/after_ram_iterate add 168 * transport-specific sections to the RAM migration data. 169 */ 170 #define RAM_SAVE_FLAG_HOOK 0x80 171 172 #define RAM_SAVE_CONTROL_NOT_SUPP -1000 173 #define RAM_SAVE_CONTROL_DELAYED -2000 174 175 size_t ram_control_save_page(QEMUFile *f, ram_addr_t block_offset, 176 ram_addr_t offset, size_t size, 177 uint64_t *bytes_sent); 178 179 void qemu_put_counted_string(QEMUFile *f, const char *name); 180 181 #endif 182