1/* SPDX-License-Identifier: MIT */
2/******************************************************************************
3 * elfnote.h
4 *
5 * Definitions used for the Xen ELF notes.
6 *
7 * Copyright (c) 2006, Ian Campbell, XenSource Ltd.
8 */
9
10#ifndef __XEN_PUBLIC_ELFNOTE_H__
11#define __XEN_PUBLIC_ELFNOTE_H__
12
13/*
14 * The notes should live in a SHT_NOTE segment and have "Xen" in the
15 * name field.
16 *
17 * Numeric types are either 4 or 8 bytes depending on the content of
18 * the desc field.
19 *
20 * LEGACY indicated the fields in the legacy __xen_guest string which
21 * this a note type replaces.
22 *
23 * String values (for non-legacy) are NULL terminated ASCII, also known
24 * as ASCIZ type.
25 */
26
27/*
28 * NAME=VALUE pair (string).
29 */
30#define XEN_ELFNOTE_INFO 0
31
32/*
33 * The virtual address of the entry point (numeric).
34 *
35 * LEGACY: VIRT_ENTRY
36 */
37#define XEN_ELFNOTE_ENTRY 1
38
39/* The virtual address of the hypercall transfer page (numeric).
40 *
41 * LEGACY: HYPERCALL_PAGE. (n.b. legacy value is a physical page
42 * number not a virtual address)
43 */
44#define XEN_ELFNOTE_HYPERCALL_PAGE 2
45
46/* The virtual address where the kernel image should be mapped (numeric).
47 *
48 * Defaults to 0.
49 *
50 * LEGACY: VIRT_BASE
51 */
52#define XEN_ELFNOTE_VIRT_BASE 3
53
54/*
55 * The offset of the ELF paddr field from the acutal required
56 * pseudo-physical address (numeric).
57 *
58 * This is used to maintain backwards compatibility with older kernels
59 * which wrote __PAGE_OFFSET into that field. This field defaults to 0
60 * if not present.
61 *
62 * LEGACY: ELF_PADDR_OFFSET. (n.b. legacy default is VIRT_BASE)
63 */
64#define XEN_ELFNOTE_PADDR_OFFSET 4
65
66/*
67 * The version of Xen that we work with (string).
68 *
69 * LEGACY: XEN_VER
70 */
71#define XEN_ELFNOTE_XEN_VERSION 5
72
73/*
74 * The name of the guest operating system (string).
75 *
76 * LEGACY: GUEST_OS
77 */
78#define XEN_ELFNOTE_GUEST_OS 6
79
80/*
81 * The version of the guest operating system (string).
82 *
83 * LEGACY: GUEST_VER
84 */
85#define XEN_ELFNOTE_GUEST_VERSION 7
86
87/*
88 * The loader type (string).
89 *
90 * LEGACY: LOADER
91 */
92#define XEN_ELFNOTE_LOADER 8
93
94/*
95 * The kernel supports PAE (x86/32 only, string = "yes" or "no").
96 *
97 * LEGACY: PAE (n.b. The legacy interface included a provision to
98 * indicate 'extended-cr3' support allowing L3 page tables to be
99 * placed above 4G. It is assumed that any kernel new enough to use
100 * these ELF notes will include this and therefore "yes" here is
101 * equivalent to "yes[entended-cr3]" in the __xen_guest interface.
102 */
103#define XEN_ELFNOTE_PAE_MODE 9
104
105/*
106 * The features supported/required by this kernel (string).
107 *
108 * The string must consist of a list of feature names (as given in
109 * features.h, without the "XENFEAT_" prefix) separated by '|'
110 * characters. If a feature is required for the kernel to function
111 * then the feature name must be preceded by a '!' character.
112 *
113 * LEGACY: FEATURES
114 */
115#define XEN_ELFNOTE_FEATURES 10
116
117/*
118 * The kernel requires the symbol table to be loaded (string = "yes" or "no")
119 * LEGACY: BSD_SYMTAB (n.b. The legacy treated the presence or absence
120 * of this string as a boolean flag rather than requiring "yes" or
121 * "no".
122 */
123#define XEN_ELFNOTE_BSD_SYMTAB 11
124
125/*
126 * The lowest address the hypervisor hole can begin at (numeric).
127 *
128 * This must not be set higher than HYPERVISOR_VIRT_START. Its presence
129 * also indicates to the hypervisor that the kernel can deal with the
130 * hole starting at a higher address.
131 */
132#define XEN_ELFNOTE_HV_START_LOW 12
133
134/*
135 * List of maddr_t-sized mask/value pairs describing how to recognize
136 * (non-present) L1 page table entries carrying valid MFNs (numeric).
137 */
138#define XEN_ELFNOTE_L1_MFN_VALID 13
139
140/*
141 * Whether or not the guest supports cooperative suspend cancellation.
142 * This is a numeric value.
143 *
144 * Default is 0
145 */
146#define XEN_ELFNOTE_SUSPEND_CANCEL 14
147
148/*
149 * The (non-default) location the initial phys-to-machine map should be
150 * placed at by the hypervisor (Dom0) or the tools (DomU).
151 * The kernel must be prepared for this mapping to be established using
152 * large pages, despite such otherwise not being available to guests.
153 * The kernel must also be able to handle the page table pages used for
154 * this mapping not being accessible through the initial mapping.
155 * (Only x86-64 supports this at present.)
156 */
157#define XEN_ELFNOTE_INIT_P2M 15
158
159/*
160 * Whether or not the guest can deal with being passed an initrd not
161 * mapped through its initial page tables.
162 */
163#define XEN_ELFNOTE_MOD_START_PFN 16
164
165/*
166 * The features supported by this kernel (numeric).
167 *
168 * Other than XEN_ELFNOTE_FEATURES on pre-4.2 Xen, this note allows a
169 * kernel to specify support for features that older hypervisors don't
170 * know about. The set of features 4.2 and newer hypervisors will
171 * consider supported by the kernel is the combination of the sets
172 * specified through this and the string note.
173 *
174 * LEGACY: FEATURES
175 */
176#define XEN_ELFNOTE_SUPPORTED_FEATURES 17
177
178/*
179 * Physical entry point into the kernel.
180 *
181 * 32bit entry point into the kernel. When requested to launch the
182 * guest kernel in a HVM container, Xen will use this entry point to
183 * launch the guest in 32bit protected mode with paging disabled.
184 * Ignored otherwise.
185 */
186#define XEN_ELFNOTE_PHYS32_ENTRY 18
187
188/*
189 * The number of the highest elfnote defined.
190 */
191#define XEN_ELFNOTE_MAX XEN_ELFNOTE_PHYS32_ENTRY
192
193#endif /* __XEN_PUBLIC_ELFNOTE_H__ */
194

source code of linux/include/xen/interface/elfnote.h