1/*
2 * hvm/save.h
3 *
4 * Structure definitions for HVM state that is held by Xen and must
5 * be saved along with the domain's memory and device-model state.
6 *
7 * Copyright (c) 2007 XenSource Ltd.
8 *
9 * Permission is hereby granted, free of charge, to any person obtaining a copy
10 * of this software and associated documentation files (the "Software"), to
11 * deal in the Software without restriction, including without limitation the
12 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
13 * sell copies of the Software, and to permit persons to whom the Software is
14 * furnished to do so, subject to the following conditions:
15 *
16 * The above copyright notice and this permission notice shall be included in
17 * all copies or substantial portions of the Software.
18 *
19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
22 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
23 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
24 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
25 * DEALINGS IN THE SOFTWARE.
26 */
27
28#ifndef __XEN_PUBLIC_HVM_SAVE_H__
29#define __XEN_PUBLIC_HVM_SAVE_H__
30
31/*
32 * Structures in this header *must* have the same layout in 32bit
33 * and 64bit environments: this means that all fields must be explicitly
34 * sized types and aligned to their sizes, and the structs must be
35 * a multiple of eight bytes long.
36 *
37 * Only the state necessary for saving and restoring (i.e. fields
38 * that are analogous to actual hardware state) should go in this file.
39 * Internal mechanisms should be kept in Xen-private headers.
40 */
41
42#if !defined(__GNUC__) || defined(__STRICT_ANSI__)
43#error "Anonymous structs/unions are a GNU extension."
44#endif
45
46/*
47 * Each entry is preceded by a descriptor giving its type and length
48 */
49struct hvm_save_descriptor {
50    uint16_t typecode;          /* Used to demux the various types below */
51    uint16_t instance;          /* Further demux within a type */
52    uint32_t length;            /* In bytes, *not* including this descriptor */
53};
54
55
56/*
57 * Each entry has a datatype associated with it: for example, the CPU state
58 * is saved as a HVM_SAVE_TYPE(CPU), which has HVM_SAVE_LENGTH(CPU),
59 * and is identified by a descriptor with typecode HVM_SAVE_CODE(CPU).
60 * DECLARE_HVM_SAVE_TYPE binds these things together with some type-system
61 * ugliness.
62 */
63
64#ifdef __XEN__
65# define DECLARE_HVM_SAVE_TYPE_COMPAT(_x, _code, _type, _ctype, _fix)     \
66    static inline int __HVM_SAVE_FIX_COMPAT_##_x(void *h, uint32_t size)  \
67        { return _fix(h, size); }                                         \
68    struct __HVM_SAVE_TYPE_##_x { _type t; char c[_code]; char cpt[2];};  \
69    struct __HVM_SAVE_TYPE_COMPAT_##_x { _ctype t; }
70
71# include <xen/lib.h> /* BUG() */
72# define DECLARE_HVM_SAVE_TYPE(_x, _code, _type)                         \
73    static inline int __HVM_SAVE_FIX_COMPAT_##_x(void *h, uint32_t size) \
74        { BUG(); return -1; }                                            \
75    struct __HVM_SAVE_TYPE_##_x { _type t; char c[_code]; char cpt[1];}; \
76    struct __HVM_SAVE_TYPE_COMPAT_##_x { _type t; }
77#else
78# define DECLARE_HVM_SAVE_TYPE_COMPAT(_x, _code, _type, _ctype, _fix)     \
79    struct __HVM_SAVE_TYPE_##_x { _type t; char c[_code]; char cpt[2];}
80
81# define DECLARE_HVM_SAVE_TYPE(_x, _code, _type)                         \
82    struct __HVM_SAVE_TYPE_##_x { _type t; char c[_code]; char cpt[1];}
83#endif
84
85#define HVM_SAVE_TYPE(_x) __typeof__ (((struct __HVM_SAVE_TYPE_##_x *)(0))->t)
86#define HVM_SAVE_LENGTH(_x) (sizeof (HVM_SAVE_TYPE(_x)))
87#define HVM_SAVE_CODE(_x) (sizeof (((struct __HVM_SAVE_TYPE_##_x *)(0))->c))
88
89#ifdef __XEN__
90# define HVM_SAVE_TYPE_COMPAT(_x) __typeof__ (((struct __HVM_SAVE_TYPE_COMPAT_##_x *)(0))->t)
91# define HVM_SAVE_LENGTH_COMPAT(_x) (sizeof (HVM_SAVE_TYPE_COMPAT(_x)))
92
93# define HVM_SAVE_HAS_COMPAT(_x) (sizeof (((struct __HVM_SAVE_TYPE_##_x *)(0))->cpt)-1)
94# define HVM_SAVE_FIX_COMPAT(_x, _dst, _size) __HVM_SAVE_FIX_COMPAT_##_x(_dst, _size)
95#endif
96
97/*
98 * The series of save records is teminated by a zero-type, zero-length
99 * descriptor.
100 */
101
102struct hvm_save_end {};
103DECLARE_HVM_SAVE_TYPE(END, 0, struct hvm_save_end);
104
105#if defined(__i386__) || defined(__x86_64__)
106#include "../arch-x86/hvm/save.h"
107#elif defined(__arm__) || defined(__aarch64__)
108#include "../arch-arm/hvm/save.h"
109#else
110#error "unsupported architecture"
111#endif
112
113#endif /* __XEN_PUBLIC_HVM_SAVE_H__ */
114