elfnote.h (5384B)
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__ */