xen/interface/elfnote.h

0001 /* SPDX-License-Identifier: MIT */
0002 /******************************************************************************
0003  * elfnote.h
0004  *
0005  * Definitions used for the Xen ELF notes.
0006  *
0007  * Copyright (c) 2006, Ian Campbell, XenSource Ltd.
0008  */
0009
0010 #ifndef __XEN_PUBLIC_ELFNOTE_H__
0011 #define __XEN_PUBLIC_ELFNOTE_H__
0012
0013 /*
0014  * The notes should live in a SHT_NOTE segment and have "Xen" in the
0015  * name field.
0016  *
0017  * Numeric types are either 4 or 8 bytes depending on the content of
0018  * the desc field.
0019  *
0020  * LEGACY indicated the fields in the legacy __xen_guest string which
0021  * this a note type replaces.
0022  *
0023  * String values (for non-legacy) are NULL terminated ASCII, also known
0024  * as ASCIZ type.
0025  */
0026
0027 /*
0028  * NAME=VALUE pair (string).
0029  */
0030 #define XEN_ELFNOTE_INFO           0
0031
0032 /*
0033  * The virtual address of the entry point (numeric).
0034  *
0035  * LEGACY: VIRT_ENTRY
0036  */
0037 #define XEN_ELFNOTE_ENTRY          1
0038
0039 /* The virtual address of the hypercall transfer page (numeric).
0040  *
0041  * LEGACY: HYPERCALL_PAGE. (n.b. legacy value is a physical page
0042  * number not a virtual address)
0043  */
0044 #define XEN_ELFNOTE_HYPERCALL_PAGE 2
0045
0046 /* The virtual address where the kernel image should be mapped (numeric).
0047  *
0048  * Defaults to 0.
0049  *
0050  * LEGACY: VIRT_BASE
0051  */
0052 #define XEN_ELFNOTE_VIRT_BASE      3
0053
0054 /*
0055  * The offset of the ELF paddr field from the acutal required
0056  * pseudo-physical address (numeric).
0057  *
0058  * This is used to maintain backwards compatibility with older kernels
0059  * which wrote __PAGE_OFFSET into that field. This field defaults to 0
0060  * if not present.
0061  *
0062  * LEGACY: ELF_PADDR_OFFSET. (n.b. legacy default is VIRT_BASE)
0063  */
0064 #define XEN_ELFNOTE_PADDR_OFFSET   4
0065
0066 /*
0067  * The version of Xen that we work with (string).
0068  *
0069  * LEGACY: XEN_VER
0070  */
0071 #define XEN_ELFNOTE_XEN_VERSION    5
0072
0073 /*
0074  * The name of the guest operating system (string).
0075  *
0076  * LEGACY: GUEST_OS
0077  */
0078 #define XEN_ELFNOTE_GUEST_OS       6
0079
0080 /*
0081  * The version of the guest operating system (string).
0082  *
0083  * LEGACY: GUEST_VER
0084  */
0085 #define XEN_ELFNOTE_GUEST_VERSION  7
0086
0087 /*
0088  * The loader type (string).
0089  *
0090  * LEGACY: LOADER
0091  */
0092 #define XEN_ELFNOTE_LOADER         8
0093
0094 /*
0095  * The kernel supports PAE (x86/32 only, string = "yes" or "no").
0096  *
0097  * LEGACY: PAE (n.b. The legacy interface included a provision to
0098  * indicate 'extended-cr3' support allowing L3 page tables to be
0099  * placed above 4G. It is assumed that any kernel new enough to use
0100  * these ELF notes will include this and therefore "yes" here is
0101  * equivalent to "yes[entended-cr3]" in the __xen_guest interface.
0102  */
0103 #define XEN_ELFNOTE_PAE_MODE       9
0104
0105 /*
0106  * The features supported/required by this kernel (string).
0107  *
0108  * The string must consist of a list of feature names (as given in
0109  * features.h, without the "XENFEAT_" prefix) separated by '|'
0110  * characters. If a feature is required for the kernel to function
0111  * then the feature name must be preceded by a '!' character.
0112  *
0113  * LEGACY: FEATURES
0114  */
0115 #define XEN_ELFNOTE_FEATURES      10
0116
0117 /*
0118  * The kernel requires the symbol table to be loaded (string = "yes" or "no")
0119  * LEGACY: BSD_SYMTAB (n.b. The legacy treated the presence or absence
0120  * of this string as a boolean flag rather than requiring "yes" or
0121  * "no".
0122  */
0123 #define XEN_ELFNOTE_BSD_SYMTAB    11
0124
0125 /*
0126  * The lowest address the hypervisor hole can begin at (numeric).
0127  *
0128  * This must not be set higher than HYPERVISOR_VIRT_START. Its presence
0129  * also indicates to the hypervisor that the kernel can deal with the
0130  * hole starting at a higher address.
0131  */
0132 #define XEN_ELFNOTE_HV_START_LOW  12
0133
0134 /*
0135  * List of maddr_t-sized mask/value pairs describing how to recognize
0136  * (non-present) L1 page table entries carrying valid MFNs (numeric).
0137  */
0138 #define XEN_ELFNOTE_L1_MFN_VALID  13
0139
0140 /*
0141  * Whether or not the guest supports cooperative suspend cancellation.
0142  * This is a numeric value.
0143  *
0144  * Default is 0
0145  */
0146 #define XEN_ELFNOTE_SUSPEND_CANCEL 14
0147
0148 /*
0149  * The (non-default) location the initial phys-to-machine map should be
0150  * placed at by the hypervisor (Dom0) or the tools (DomU).
0151  * The kernel must be prepared for this mapping to be established using
0152  * large pages, despite such otherwise not being available to guests.
0153  * The kernel must also be able to handle the page table pages used for
0154  * this mapping not being accessible through the initial mapping.
0155  * (Only x86-64 supports this at present.)
0156  */
0157 #define XEN_ELFNOTE_INIT_P2M      15
0158
0159 /*
0160  * Whether or not the guest can deal with being passed an initrd not
0161  * mapped through its initial page tables.
0162  */
0163 #define XEN_ELFNOTE_MOD_START_PFN 16
0164
0165 /*
0166  * The features supported by this kernel (numeric).
0167  *
0168  * Other than XEN_ELFNOTE_FEATURES on pre-4.2 Xen, this note allows a
0169  * kernel to specify support for features that older hypervisors don't
0170  * know about. The set of features 4.2 and newer hypervisors will
0171  * consider supported by the kernel is the combination of the sets
0172  * specified through this and the string note.
0173  *
0174  * LEGACY: FEATURES
0175  */
0176 #define XEN_ELFNOTE_SUPPORTED_FEATURES 17
0177
0178 /*
0179  * Physical entry point into the kernel.
0180  *
0181  * 32bit entry point into the kernel. When requested to launch the
0182  * guest kernel in a HVM container, Xen will use this entry point to
0183  * launch the guest in 32bit protected mode with paging disabled.
0184  * Ignored otherwise.
0185  */
0186 #define XEN_ELFNOTE_PHYS32_ENTRY 18
0187
0188 /*
0189  * The number of the highest elfnote defined.
0190  */
0191 #define XEN_ELFNOTE_MAX XEN_ELFNOTE_PHYS32_ENTRY
0192
0193 #endif /* __XEN_PUBLIC_ELFNOTE_H__ */