qemu/migration/qemu-file.h
Marc-André Lureau d890344166 slirp: use libslirp migration code
slirp migration code uses QEMU vmstate so far, when building WITH_QEMU.

Introduce slirp_state_{load,save,version}() functions to move the
state saving handling to libslirp side.

So far, the bitstream compatibility should remain equal with current
QEMU, as this is effectively using the same code, with the same format
etc. When libslirp is made standalone, we will need some mechanism to
ensure bitstream compatibility regardless of the libslirp version
installed. See the FIXME note in the code.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190212162524.31504-3-marcandre.lureau@redhat.com>
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
2019-03-07 12:46:31 +01:00

181 lines
6.4 KiB
C

/*
* QEMU System Emulator
*
* Copyright (c) 2003-2008 Fabrice Bellard
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#ifndef MIGRATION_QEMU_FILE_H
#define MIGRATION_QEMU_FILE_H
#include <zlib.h>
/* Read a chunk of data from a file at the given position. The pos argument
* can be ignored if the file is only be used for streaming. The number of
* bytes actually read should be returned.
*/
typedef ssize_t (QEMUFileGetBufferFunc)(void *opaque, uint8_t *buf,
int64_t pos, size_t size);
/* Close a file
*
* Return negative error number on error, 0 or positive value on success.
*
* The meaning of return value on success depends on the specific back-end being
* used.
*/
typedef int (QEMUFileCloseFunc)(void *opaque);
/* Called to return the OS file descriptor associated to the QEMUFile.
*/
typedef int (QEMUFileGetFD)(void *opaque);
/* Called to change the blocking mode of the file
*/
typedef int (QEMUFileSetBlocking)(void *opaque, bool enabled);
/*
* This function writes an iovec to file. The handler must write all
* of the data or return a negative errno value.
*/
typedef ssize_t (QEMUFileWritevBufferFunc)(void *opaque, struct iovec *iov,
int iovcnt, int64_t pos);
/*
* This function provides hooks around different
* stages of RAM migration.
* 'opaque' is the backend specific data in QEMUFile
* 'data' is call specific data associated with the 'flags' value
*/
typedef int (QEMURamHookFunc)(QEMUFile *f, void *opaque, uint64_t flags,
void *data);
/*
* Constants used by ram_control_* hooks
*/
#define RAM_CONTROL_SETUP 0
#define RAM_CONTROL_ROUND 1
#define RAM_CONTROL_HOOK 2
#define RAM_CONTROL_FINISH 3
#define RAM_CONTROL_BLOCK_REG 4
/*
* This function allows override of where the RAM page
* is saved (such as RDMA, for example.)
*/
typedef size_t (QEMURamSaveFunc)(QEMUFile *f, void *opaque,
ram_addr_t block_offset,
ram_addr_t offset,
size_t size,
uint64_t *bytes_sent);
/*
* Return a QEMUFile for comms in the opposite direction
*/
typedef QEMUFile *(QEMURetPathFunc)(void *opaque);
/*
* Stop any read or write (depending on flags) on the underlying
* transport on the QEMUFile.
* Existing blocking reads/writes must be woken
* Returns 0 on success, -err on error
*/
typedef int (QEMUFileShutdownFunc)(void *opaque, bool rd, bool wr);
typedef struct QEMUFileOps {
QEMUFileGetBufferFunc *get_buffer;
QEMUFileCloseFunc *close;
QEMUFileSetBlocking *set_blocking;
QEMUFileWritevBufferFunc *writev_buffer;
QEMURetPathFunc *get_return_path;
QEMUFileShutdownFunc *shut_down;
} QEMUFileOps;
typedef struct QEMUFileHooks {
QEMURamHookFunc *before_ram_iterate;
QEMURamHookFunc *after_ram_iterate;
QEMURamHookFunc *hook_ram_load;
QEMURamSaveFunc *save_page;
} QEMUFileHooks;
QEMUFile *qemu_fopen_ops(void *opaque, const QEMUFileOps *ops);
void qemu_file_set_hooks(QEMUFile *f, const QEMUFileHooks *hooks);
int qemu_get_fd(QEMUFile *f);
int qemu_fclose(QEMUFile *f);
int64_t qemu_ftell(QEMUFile *f);
int64_t qemu_ftell_fast(QEMUFile *f);
/*
* put_buffer without copying the buffer.
* The buffer should be available till it is sent asynchronously.
*/
void qemu_put_buffer_async(QEMUFile *f, const uint8_t *buf, size_t size,
bool may_free);
bool qemu_file_mode_is_not_valid(const char *mode);
bool qemu_file_is_writable(QEMUFile *f);
#include "migration/qemu-file-types.h"
size_t qemu_peek_buffer(QEMUFile *f, uint8_t **buf, size_t size, size_t offset);
size_t qemu_get_buffer_in_place(QEMUFile *f, uint8_t **buf, size_t size);
ssize_t qemu_put_compression_data(QEMUFile *f, z_stream *stream,
const uint8_t *p, size_t size);
int qemu_put_qemu_file(QEMUFile *f_des, QEMUFile *f_src);
/*
* Note that you can only peek continuous bytes from where the current pointer
* is; you aren't guaranteed to be able to peak to +n bytes unless you've
* previously peeked +n-1.
*/
int qemu_peek_byte(QEMUFile *f, int offset);
void qemu_file_skip(QEMUFile *f, int size);
void qemu_update_position(QEMUFile *f, size_t size);
void qemu_file_reset_rate_limit(QEMUFile *f);
void qemu_file_set_rate_limit(QEMUFile *f, int64_t new_rate);
int64_t qemu_file_get_rate_limit(QEMUFile *f);
void qemu_file_set_error(QEMUFile *f, int ret);
int qemu_file_shutdown(QEMUFile *f);
QEMUFile *qemu_file_get_return_path(QEMUFile *f);
void qemu_fflush(QEMUFile *f);
void qemu_file_set_blocking(QEMUFile *f, bool block);
size_t qemu_get_counted_string(QEMUFile *f, char buf[256]);
void ram_control_before_iterate(QEMUFile *f, uint64_t flags);
void ram_control_after_iterate(QEMUFile *f, uint64_t flags);
void ram_control_load_hook(QEMUFile *f, uint64_t flags, void *data);
/* Whenever this is found in the data stream, the flags
* will be passed to ram_control_load_hook in the incoming-migration
* side. This lets before_ram_iterate/after_ram_iterate add
* transport-specific sections to the RAM migration data.
*/
#define RAM_SAVE_FLAG_HOOK 0x80
#define RAM_SAVE_CONTROL_NOT_SUPP -1000
#define RAM_SAVE_CONTROL_DELAYED -2000
size_t ram_control_save_page(QEMUFile *f, ram_addr_t block_offset,
ram_addr_t offset, size_t size,
uint64_t *bytes_sent);
void qemu_put_counted_string(QEMUFile *f, const char *name);
#endif