xen/interface/features.h

0001 /* SPDX-License-Identifier: MIT */
0002 /******************************************************************************
0003  * features.h
0004  *
0005  * Feature flags, reported by XENVER_get_features.
0006  *
0007  * Copyright (c) 2006, Keir Fraser <keir@xensource.com>
0008  */
0009
0010 #ifndef __XEN_PUBLIC_FEATURES_H__
0011 #define __XEN_PUBLIC_FEATURES_H__
0012
0013 /*
0014  * If set, the guest does not need to write-protect its pagetables, and can
0015  * update them via direct writes.
0016  */
0017 #define XENFEAT_writable_page_tables       0
0018
0019 /*
0020  * If set, the guest does not need to write-protect its segment descriptor
0021  * tables, and can update them via direct writes.
0022  */
0023 #define XENFEAT_writable_descriptor_tables 1
0024
0025 /*
0026  * If set, translation between the guest's 'pseudo-physical' address space
0027  * and the host's machine address space are handled by the hypervisor. In this
0028  * mode the guest does not need to perform phys-to/from-machine translations
0029  * when performing page table operations.
0030  */
0031 #define XENFEAT_auto_translated_physmap    2
0032
0033 /* If set, the guest is running in supervisor mode (e.g., x86 ring 0). */
0034 #define XENFEAT_supervisor_mode_kernel     3
0035
0036 /*
0037  * If set, the guest does not need to allocate x86 PAE page directories
0038  * below 4GB. This flag is usually implied by auto_translated_physmap.
0039  */
0040 #define XENFEAT_pae_pgdir_above_4gb        4
0041
0042 /* x86: Does this Xen host support the MMU_PT_UPDATE_PRESERVE_AD hypercall? */
0043 #define XENFEAT_mmu_pt_update_preserve_ad  5
0044
0045 /* x86: Does this Xen host support the MMU_{CLEAR,COPY}_PAGE hypercall? */
0046 #define XENFEAT_highmem_assist             6
0047
0048 /*
0049  * If set, GNTTABOP_map_grant_ref honors flags to be placed into guest kernel
0050  * available pte bits.
0051  */
0052 #define XENFEAT_gnttab_map_avail_bits      7
0053
0054 /* x86: Does this Xen host support the HVM callback vector type? */
0055 #define XENFEAT_hvm_callback_vector        8
0056
0057 /* x86: pvclock algorithm is safe to use on HVM */
0058 #define XENFEAT_hvm_safe_pvclock           9
0059
0060 /* x86: pirq can be used by HVM guests */
0061 #define XENFEAT_hvm_pirqs           10
0062
0063 /* operation as Dom0 is supported */
0064 #define XENFEAT_dom0                      11
0065
0066 /* Xen also maps grant references at pfn = mfn.
0067  * This feature flag is deprecated and should not be used.
0068 #define XENFEAT_grant_map_identity        12
0069  */
0070
0071 /* Guest can use XENMEMF_vnode to specify virtual node for memory op. */
0072 #define XENFEAT_memory_op_vnode_supported 13
0073
0074 /* arm: Hypervisor supports ARM SMC calling convention. */
0075 #define XENFEAT_ARM_SMCCC_supported       14
0076
0077 /*
0078  * x86/PVH: If set, ACPI RSDP can be placed at any address. Otherwise RSDP
0079  * must be located in lower 1MB, as required by ACPI Specification for IA-PC
0080  * systems.
0081  * This feature flag is only consulted if XEN_ELFNOTE_GUEST_OS contains
0082  * the "linux" string.
0083  */
0084 #define XENFEAT_linux_rsdp_unrestricted   15
0085
0086 /*
0087  * A direct-mapped (or 1:1 mapped) domain is a domain for which its
0088  * local pages have gfn == mfn. If a domain is direct-mapped,
0089  * XENFEAT_direct_mapped is set; otherwise XENFEAT_not_direct_mapped
0090  * is set.
0091  *
0092  * If neither flag is set (e.g. older Xen releases) the assumptions are:
0093  * - not auto_translated domains (x86 only) are always direct-mapped
0094  * - on x86, auto_translated domains are not direct-mapped
0095  * - on ARM, Dom0 is direct-mapped, DomUs are not
0096  */
0097 #define XENFEAT_not_direct_mapped         16
0098 #define XENFEAT_direct_mapped             17
0099
0100 #define XENFEAT_NR_SUBMAPS 1
0101
0102 #endif /* __XEN_PUBLIC_FEATURES_H__ */