include/hw/xen/interface/features.h

   1 /* SPDX-License-Identifier: MIT */
   2 /******************************************************************************
   3  * features.h
   4  *
   5  * Feature flags, reported by XENVER_get_features.
   6  *
   7  * Copyright (c) 2006, Keir Fraser <keir@xensource.com>
   8  */
   9
  10 #ifndef __XEN_PUBLIC_FEATURES_H__
  11 #define __XEN_PUBLIC_FEATURES_H__
  12
  13 /*
  14  * `incontents 200 elfnotes_features XEN_ELFNOTE_FEATURES
  15  *
  16  * The list of all the features the guest supports. They are set by
  17  * parsing the XEN_ELFNOTE_FEATURES and XEN_ELFNOTE_SUPPORTED_FEATURES
  18  * string. The format is the  feature names (as given here without the
  19  * "XENFEAT_" prefix) separated by '|' characters.
  20  * If a feature is required for the kernel to function then the feature name
  21  * must be preceded by a '!' character.
  22  *
  23  * Note that if XEN_ELFNOTE_SUPPORTED_FEATURES is used, then in the
  24  * XENFEAT_dom0 MUST be set if the guest is to be booted as dom0,
  25  */
  26
  27 /*
  28  * If set, the guest does not need to write-protect its pagetables, and can
  29  * update them via direct writes.
  30  */
  31 #define XENFEAT_writable_page_tables       0
  32
  33 /*
  34  * If set, the guest does not need to write-protect its segment descriptor
  35  * tables, and can update them via direct writes.
  36  */
  37 #define XENFEAT_writable_descriptor_tables 1
  38
  39 /*
  40  * If set, translation between the guest's 'pseudo-physical' address space
  41  * and the host's machine address space are handled by the hypervisor. In this
  42  * mode the guest does not need to perform phys-to/from-machine translations
  43  * when performing page table operations.
  44  */
  45 #define XENFEAT_auto_translated_physmap    2
  46
  47 /* If set, the guest is running in supervisor mode (e.g., x86 ring 0). */
  48 #define XENFEAT_supervisor_mode_kernel     3
  49
  50 /*
  51  * If set, the guest does not need to allocate x86 PAE page directories
  52  * below 4GB. This flag is usually implied by auto_translated_physmap.
  53  */
  54 #define XENFEAT_pae_pgdir_above_4gb        4
  55
  56 /* x86: Does this Xen host support the MMU_PT_UPDATE_PRESERVE_AD hypercall? */
  57 #define XENFEAT_mmu_pt_update_preserve_ad  5
  58
  59 /* x86: Does this Xen host support the MMU_{CLEAR,COPY}_PAGE hypercall? */
  60 #define XENFEAT_highmem_assist             6
  61
  62 /*
  63  * If set, GNTTABOP_map_grant_ref honors flags to be placed into guest kernel
  64  * available pte bits.
  65  */
  66 #define XENFEAT_gnttab_map_avail_bits      7
  67
  68 /* x86: Does this Xen host support the HVM callback vector type? */
  69 #define XENFEAT_hvm_callback_vector        8
  70
  71 /* x86: pvclock algorithm is safe to use on HVM */
  72 #define XENFEAT_hvm_safe_pvclock           9
  73
  74 /* x86: pirq can be used by HVM guests */
  75 #define XENFEAT_hvm_pirqs                 10
  76
  77 /* operation as Dom0 is supported */
  78 #define XENFEAT_dom0                      11
  79
  80 /* Xen also maps grant references at pfn = mfn.
  81  * This feature flag is deprecated and should not be used.
  82 #define XENFEAT_grant_map_identity        12
  83  */
  84
  85 /* Guest can use XENMEMF_vnode to specify virtual node for memory op. */
  86 #define XENFEAT_memory_op_vnode_supported 13
  87
  88 /* arm: Hypervisor supports ARM SMC calling convention. */
  89 #define XENFEAT_ARM_SMCCC_supported       14
  90
  91 /*
  92  * x86/PVH: If set, ACPI RSDP can be placed at any address. Otherwise RSDP
  93  * must be located in lower 1MB, as required by ACPI Specification for IA-PC
  94  * systems.
  95  * This feature flag is only consulted if XEN_ELFNOTE_GUEST_OS contains
  96  * the "linux" string.
  97  */
  98 #define XENFEAT_linux_rsdp_unrestricted   15
  99
 100 /*
 101  * A direct-mapped (or 1:1 mapped) domain is a domain for which its
 102  * local pages have gfn == mfn. If a domain is direct-mapped,
 103  * XENFEAT_direct_mapped is set; otherwise XENFEAT_not_direct_mapped
 104  * is set.
 105  *
 106  * If neither flag is set (e.g. older Xen releases) the assumptions are:
 107  * - not auto_translated domains (x86 only) are always direct-mapped
 108  * - on x86, auto_translated domains are not direct-mapped
 109  * - on ARM, Dom0 is direct-mapped, DomUs are not
 110  */
 111 #define XENFEAT_not_direct_mapped         16
 112 #define XENFEAT_direct_mapped             17
 113
 114 #define XENFEAT_NR_SUBMAPS 1
 115
 116 #endif /* __XEN_PUBLIC_FEATURES_H__ */
 117
 118 /*
 119  * Local variables:
 120  * mode: C
 121  * c-file-style: "BSD"
 122  * c-basic-offset: 4
 123  * tab-width: 4
 124  * indent-tabs-mode: nil
 125  * End:
 126  */