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/* SPDX-License-Identifier: BSD-3-Clause */
/*
* QEMU migration/snapshot declarations
*
* Copyright (c) 2009-2011 Red Hat, Inc.
*
* Original author: Juan Quintela <quintela@redhat.com>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer.
*
* 2. Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
* with the distribution.
*
* 3. Neither the name of the copyright holder nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef VMSTATE_H_
#define VMSTATE_H_
#include <unistd.h>
#include <stdint.h>
#include <stdbool.h>
#include "slirp.h"
#include "stream.h"
#define stringify(s) tostring(s)
#define tostring(s) #s
typedef struct VMStateInfo VMStateInfo;
typedef struct VMStateDescription VMStateDescription;
typedef struct VMStateField VMStateField;
int slirp_vmstate_save_state(SlirpOStream *f, const VMStateDescription *vmsd,
void *opaque);
int slirp_vmstate_load_state(SlirpIStream *f, const VMStateDescription *vmsd,
void *opaque, int version_id);
/* VMStateInfo allows customized migration of objects that don't fit in
* any category in VMStateFlags. Additional information is always passed
* into get and put in terms of field and vmdesc parameters. However
* these two parameters should only be used in cases when customized
* handling is needed, such as QTAILQ. For primitive data types such as
* integer, field and vmdesc parameters should be ignored inside get/put.
*/
struct VMStateInfo {
const char *name;
int (*get)(SlirpIStream *f, void *pv, size_t size,
const VMStateField *field);
int (*put)(SlirpOStream *f, void *pv, size_t size,
const VMStateField *field);
};
enum VMStateFlags {
/* Ignored */
VMS_SINGLE = 0x001,
/* The struct member at opaque + VMStateField.offset is a pointer
* to the actual field (e.g. struct a { uint8_t *b;
* }). Dereference the pointer before using it as basis for
* further pointer arithmetic (see e.g. VMS_ARRAY). Does not
* affect the meaning of VMStateField.num_offset or
* VMStateField.size_offset; see VMS_VARRAY* and VMS_VBUFFER for
* those. */
VMS_POINTER = 0x002,
/* The field is an array of fixed size. VMStateField.num contains
* the number of entries in the array. The size of each entry is
* given by VMStateField.size and / or opaque +
* VMStateField.size_offset; see VMS_VBUFFER and
* VMS_MULTIPLY. Each array entry will be processed individually
* (VMStateField.info.get()/put() if VMS_STRUCT is not set,
* recursion into VMStateField.vmsd if VMS_STRUCT is set). May not
* be combined with VMS_VARRAY*. */
VMS_ARRAY = 0x004,
/* The field is itself a struct, containing one or more
* fields. Recurse into VMStateField.vmsd. Most useful in
* combination with VMS_ARRAY / VMS_VARRAY*, recursing into each
* array entry. */
VMS_STRUCT = 0x008,
/* The field is an array of variable size. The int32_t at opaque +
* VMStateField.num_offset contains the number of entries in the
* array. See the VMS_ARRAY description regarding array handling
* in general. May not be combined with VMS_ARRAY or any other
* VMS_VARRAY*. */
VMS_VARRAY_INT32 = 0x010,
/* Ignored */
VMS_BUFFER = 0x020,
/* The field is a (fixed-size or variable-size) array of pointers
* (e.g. struct a { uint8_t *b[]; }). Dereference each array entry
* before using it. Note: Does not imply any one of VMS_ARRAY /
* VMS_VARRAY*; these need to be set explicitly. */
VMS_ARRAY_OF_POINTER = 0x040,
/* The field is an array of variable size. The uint16_t at opaque
* + VMStateField.num_offset (subject to VMS_MULTIPLY_ELEMENTS)
* contains the number of entries in the array. See the VMS_ARRAY
* description regarding array handling in general. May not be
* combined with VMS_ARRAY or any other VMS_VARRAY*. */
VMS_VARRAY_UINT16 = 0x080,
/* The size of the individual entries (a single array entry if
* VMS_ARRAY or any of VMS_VARRAY* are set, or the field itself if
* neither is set) is variable (i.e. not known at compile-time),
* but the same for all entries. Use the int32_t at opaque +
* VMStateField.size_offset (subject to VMS_MULTIPLY) to determine
* the size of each (and every) entry. */
VMS_VBUFFER = 0x100,
/* Multiply the entry size given by the int32_t at opaque +
* VMStateField.size_offset (see VMS_VBUFFER description) with
* VMStateField.size to determine the number of bytes to be
* allocated. Only valid in combination with VMS_VBUFFER. */
VMS_MULTIPLY = 0x200,
/* The field is an array of variable size. The uint8_t at opaque +
* VMStateField.num_offset (subject to VMS_MULTIPLY_ELEMENTS)
* contains the number of entries in the array. See the VMS_ARRAY
* description regarding array handling in general. May not be
* combined with VMS_ARRAY or any other VMS_VARRAY*. */
VMS_VARRAY_UINT8 = 0x400,
/* The field is an array of variable size. The uint32_t at opaque
* + VMStateField.num_offset (subject to VMS_MULTIPLY_ELEMENTS)
* contains the number of entries in the array. See the VMS_ARRAY
* description regarding array handling in general. May not be
* combined with VMS_ARRAY or any other VMS_VARRAY*. */
VMS_VARRAY_UINT32 = 0x800,
/* Fail loading the serialised VM state if this field is missing
* from the input. */
VMS_MUST_EXIST = 0x1000,
/* When loading serialised VM state, allocate memory for the
* (entire) field. Only valid in combination with
* VMS_POINTER. Note: Not all combinations with other flags are
* currently supported, e.g. VMS_ALLOC|VMS_ARRAY_OF_POINTER won't
* cause the individual entries to be allocated. */
VMS_ALLOC = 0x2000,
/* Multiply the number of entries given by the integer at opaque +
* VMStateField.num_offset (see VMS_VARRAY*) with VMStateField.num
* to determine the number of entries in the array. Only valid in
* combination with one of VMS_VARRAY*. */
VMS_MULTIPLY_ELEMENTS = 0x4000,
/* A structure field that is like VMS_STRUCT, but uses
* VMStateField.struct_version_id to tell which version of the
* structure we are referencing to use. */
VMS_VSTRUCT = 0x8000,
};
struct VMStateField {
const char *name;
size_t offset;
size_t size;
size_t start;
int num;
size_t num_offset;
size_t size_offset;
const VMStateInfo *info;
enum VMStateFlags flags;
const VMStateDescription *vmsd;
int version_id;
int struct_version_id;
bool (*field_exists)(void *opaque, int version_id);
};
struct VMStateDescription {
const char *name;
int version_id;
int (*pre_load)(void *opaque);
int (*post_load)(void *opaque, int version_id);
int (*pre_save)(void *opaque);
VMStateField *fields;
};
extern const VMStateInfo slirp_vmstate_info_int16;
extern const VMStateInfo slirp_vmstate_info_int32;
extern const VMStateInfo slirp_vmstate_info_uint8;
extern const VMStateInfo slirp_vmstate_info_uint16;
extern const VMStateInfo slirp_vmstate_info_uint32;
/** Put this in the stream when migrating a null pointer.*/
#define VMS_NULLPTR_MARKER (0x30U) /* '0' */
extern const VMStateInfo slirp_vmstate_info_nullptr;
extern const VMStateInfo slirp_vmstate_info_buffer;
extern const VMStateInfo slirp_vmstate_info_tmp;
#define type_check_array(t1, t2, n) ((t1(*)[n])0 - (t2 *)0)
#define type_check_pointer(t1, t2) ((t1 **)0 - (t2 *)0)
#define typeof_field(type, field) typeof(((type *)0)->field)
#define type_check(t1, t2) ((t1 *)0 - (t2 *)0)
#define vmstate_offset_value(_state, _field, _type) \
(offsetof(_state, _field) + type_check(_type, typeof_field(_state, _field)))
#define vmstate_offset_pointer(_state, _field, _type) \
(offsetof(_state, _field) + \
type_check_pointer(_type, typeof_field(_state, _field)))
#define vmstate_offset_array(_state, _field, _type, _num) \
(offsetof(_state, _field) + \
type_check_array(_type, typeof_field(_state, _field), _num))
#define vmstate_offset_buffer(_state, _field) \
vmstate_offset_array(_state, _field, uint8_t, \
sizeof(typeof_field(_state, _field)))
/* In the macros below, if there is a _version, that means the macro's
* field will be processed only if the version being received is >=
* the _version specified. In general, if you add a new field, you
* would increment the structure's version and put that version
* number into the new field so it would only be processed with the
* new version.
*
* In particular, for VMSTATE_STRUCT() and friends the _version does
* *NOT* pick the version of the sub-structure. It works just as
* specified above. The version of the top-level structure received
* is passed down to all sub-structures. This means that the
* sub-structures must have version that are compatible with all the
* structures that use them.
*
* If you want to specify the version of the sub-structure, use
* VMSTATE_VSTRUCT(), which allows the specific sub-structure version
* to be directly specified.
*/
#define VMSTATE_SINGLE_TEST(_field, _state, _test, _version, _info, _type) \
{ \
.name = (stringify(_field)), .version_id = (_version), \
.field_exists = (_test), .size = sizeof(_type), .info = &(_info), \
.flags = VMS_SINGLE, \
.offset = vmstate_offset_value(_state, _field, _type), \
}
#define VMSTATE_ARRAY(_field, _state, _num, _version, _info, _type) \
{ \
.name = (stringify(_field)), .version_id = (_version), .num = (_num), \
.info = &(_info), .size = sizeof(_type), .flags = VMS_ARRAY, \
.offset = vmstate_offset_array(_state, _field, _type, _num), \
}
#define VMSTATE_STRUCT_TEST(_field, _state, _test, _version, _vmsd, _type) \
{ \
.name = (stringify(_field)), .version_id = (_version), \
.field_exists = (_test), .vmsd = &(_vmsd), .size = sizeof(_type), \
.flags = VMS_STRUCT, \
.offset = vmstate_offset_value(_state, _field, _type), \
}
#define VMSTATE_STRUCT_POINTER_V(_field, _state, _version, _vmsd, _type) \
{ \
.name = (stringify(_field)), .version_id = (_version), \
.vmsd = &(_vmsd), .size = sizeof(_type *), \
.flags = VMS_STRUCT | VMS_POINTER, \
.offset = vmstate_offset_pointer(_state, _field, _type), \
}
#define VMSTATE_STRUCT_ARRAY_TEST(_field, _state, _num, _test, _version, \
_vmsd, _type) \
{ \
.name = (stringify(_field)), .num = (_num), .field_exists = (_test), \
.version_id = (_version), .vmsd = &(_vmsd), .size = sizeof(_type), \
.flags = VMS_STRUCT | VMS_ARRAY, \
.offset = vmstate_offset_array(_state, _field, _type, _num), \
}
#define VMSTATE_STATIC_BUFFER(_field, _state, _version, _test, _start, _size) \
{ \
.name = (stringify(_field)), .version_id = (_version), \
.field_exists = (_test), .size = (_size - _start), \
.info = &slirp_vmstate_info_buffer, .flags = VMS_BUFFER, \
.offset = vmstate_offset_buffer(_state, _field) + _start, \
}
#define VMSTATE_VBUFFER_UINT32(_field, _state, _version, _test, _field_size) \
{ \
.name = (stringify(_field)), .version_id = (_version), \
.field_exists = (_test), \
.size_offset = vmstate_offset_value(_state, _field_size, uint32_t), \
.info = &slirp_vmstate_info_buffer, \
.flags = VMS_VBUFFER | VMS_POINTER, \
.offset = offsetof(_state, _field), \
}
#define QEMU_BUILD_BUG_ON_STRUCT(x) \
struct { \
int : (x) ? -1 : 1; \
}
#define QEMU_BUILD_BUG_ON_ZERO(x) \
(sizeof(QEMU_BUILD_BUG_ON_STRUCT(x)) - sizeof(QEMU_BUILD_BUG_ON_STRUCT(x)))
/* Allocate a temporary of type 'tmp_type', set tmp->parent to _state
* and execute the vmsd on the temporary. Note that we're working with
* the whole of _state here, not a field within it.
* We compile time check that:
* That _tmp_type contains a 'parent' member that's a pointer to the
* '_state' type
* That the pointer is right at the start of _tmp_type.
*/
#define VMSTATE_WITH_TMP(_state, _tmp_type, _vmsd) \
{ \
.name = "tmp", \
.size = sizeof(_tmp_type) + \
QEMU_BUILD_BUG_ON_ZERO(offsetof(_tmp_type, parent) != 0) + \
type_check_pointer(_state, typeof_field(_tmp_type, parent)), \
.vmsd = &(_vmsd), .info = &slirp_vmstate_info_tmp, \
}
#define VMSTATE_SINGLE(_field, _state, _version, _info, _type) \
VMSTATE_SINGLE_TEST(_field, _state, NULL, _version, _info, _type)
#define VMSTATE_STRUCT(_field, _state, _version, _vmsd, _type) \
VMSTATE_STRUCT_TEST(_field, _state, NULL, _version, _vmsd, _type)
#define VMSTATE_STRUCT_POINTER(_field, _state, _vmsd, _type) \
VMSTATE_STRUCT_POINTER_V(_field, _state, 0, _vmsd, _type)
#define VMSTATE_STRUCT_ARRAY(_field, _state, _num, _version, _vmsd, _type) \
VMSTATE_STRUCT_ARRAY_TEST(_field, _state, _num, NULL, _version, _vmsd, \
_type)
#define VMSTATE_INT16_V(_f, _s, _v) \
VMSTATE_SINGLE(_f, _s, _v, slirp_vmstate_info_int16, int16_t)
#define VMSTATE_INT32_V(_f, _s, _v) \
VMSTATE_SINGLE(_f, _s, _v, slirp_vmstate_info_int32, int32_t)
#define VMSTATE_UINT8_V(_f, _s, _v) \
VMSTATE_SINGLE(_f, _s, _v, slirp_vmstate_info_uint8, uint8_t)
#define VMSTATE_UINT16_V(_f, _s, _v) \
VMSTATE_SINGLE(_f, _s, _v, slirp_vmstate_info_uint16, uint16_t)
#define VMSTATE_UINT32_V(_f, _s, _v) \
VMSTATE_SINGLE(_f, _s, _v, slirp_vmstate_info_uint32, uint32_t)
#define VMSTATE_INT16(_f, _s) VMSTATE_INT16_V(_f, _s, 0)
#define VMSTATE_INT32(_f, _s) VMSTATE_INT32_V(_f, _s, 0)
#define VMSTATE_UINT8(_f, _s) VMSTATE_UINT8_V(_f, _s, 0)
#define VMSTATE_UINT16(_f, _s) VMSTATE_UINT16_V(_f, _s, 0)
#define VMSTATE_UINT32(_f, _s) VMSTATE_UINT32_V(_f, _s, 0)
#define VMSTATE_UINT16_TEST(_f, _s, _t) \
VMSTATE_SINGLE_TEST(_f, _s, _t, 0, slirp_vmstate_info_uint16, uint16_t)
#define VMSTATE_UINT32_TEST(_f, _s, _t) \
VMSTATE_SINGLE_TEST(_f, _s, _t, 0, slirp_vmstate_info_uint32, uint32_t)
#define VMSTATE_INT16_ARRAY_V(_f, _s, _n, _v) \
VMSTATE_ARRAY(_f, _s, _n, _v, slirp_vmstate_info_int16, int16_t)
#define VMSTATE_INT16_ARRAY(_f, _s, _n) VMSTATE_INT16_ARRAY_V(_f, _s, _n, 0)
#define VMSTATE_BUFFER_V(_f, _s, _v) \
VMSTATE_STATIC_BUFFER(_f, _s, _v, NULL, 0, sizeof(typeof_field(_s, _f)))
#define VMSTATE_BUFFER(_f, _s) VMSTATE_BUFFER_V(_f, _s, 0)
#define VMSTATE_END_OF_LIST() \
{ \
}
#endif