xref: /linux/include/xen/interface/features.h (revision 03ab8e6297acd1bc0eedaa050e2a1635c576fd11)
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  * If set, the guest does not need to write-protect its pagetables, and can
15  * update them via direct writes.
16  */
17 #define XENFEAT_writable_page_tables       0
18 
19 /*
20  * If set, the guest does not need to write-protect its segment descriptor
21  * tables, and can update them via direct writes.
22  */
23 #define XENFEAT_writable_descriptor_tables 1
24 
25 /*
26  * If set, translation between the guest's 'pseudo-physical' address space
27  * and the host's machine address space are handled by the hypervisor. In this
28  * mode the guest does not need to perform phys-to/from-machine translations
29  * when performing page table operations.
30  */
31 #define XENFEAT_auto_translated_physmap    2
32 
33 /* If set, the guest is running in supervisor mode (e.g., x86 ring 0). */
34 #define XENFEAT_supervisor_mode_kernel     3
35 
36 /*
37  * If set, the guest does not need to allocate x86 PAE page directories
38  * below 4GB. This flag is usually implied by auto_translated_physmap.
39  */
40 #define XENFEAT_pae_pgdir_above_4gb        4
41 
42 /* x86: Does this Xen host support the MMU_PT_UPDATE_PRESERVE_AD hypercall? */
43 #define XENFEAT_mmu_pt_update_preserve_ad  5
44 
45 /* x86: Does this Xen host support the MMU_{CLEAR,COPY}_PAGE hypercall? */
46 #define XENFEAT_highmem_assist             6
47 
48 /*
49  * If set, GNTTABOP_map_grant_ref honors flags to be placed into guest kernel
50  * available pte bits.
51  */
52 #define XENFEAT_gnttab_map_avail_bits      7
53 
54 /* x86: Does this Xen host support the HVM callback vector type? */
55 #define XENFEAT_hvm_callback_vector        8
56 
57 /* x86: pvclock algorithm is safe to use on HVM */
58 #define XENFEAT_hvm_safe_pvclock           9
59 
60 /* x86: pirq can be used by HVM guests */
61 #define XENFEAT_hvm_pirqs           10
62 
63 /* operation as Dom0 is supported */
64 #define XENFEAT_dom0                      11
65 
66 /* Xen also maps grant references at pfn = mfn.
67  * This feature flag is deprecated and should not be used.
68 #define XENFEAT_grant_map_identity        12
69  */
70 
71 /* Guest can use XENMEMF_vnode to specify virtual node for memory op. */
72 #define XENFEAT_memory_op_vnode_supported 13
73 
74 /* arm: Hypervisor supports ARM SMC calling convention. */
75 #define XENFEAT_ARM_SMCCC_supported       14
76 
77 /*
78  * x86/PVH: If set, ACPI RSDP can be placed at any address. Otherwise RSDP
79  * must be located in lower 1MB, as required by ACPI Specification for IA-PC
80  * systems.
81  * This feature flag is only consulted if XEN_ELFNOTE_GUEST_OS contains
82  * the "linux" string.
83  */
84 #define XENFEAT_linux_rsdp_unrestricted   15
85 
86 /*
87  * A direct-mapped (or 1:1 mapped) domain is a domain for which its
88  * local pages have gfn == mfn. If a domain is direct-mapped,
89  * XENFEAT_direct_mapped is set; otherwise XENFEAT_not_direct_mapped
90  * is set.
91  *
92  * If neither flag is set (e.g. older Xen releases) the assumptions are:
93  * - not auto_translated domains (x86 only) are always direct-mapped
94  * - on x86, auto_translated domains are not direct-mapped
95  * - on ARM, Dom0 is direct-mapped, DomUs are not
96  */
97 #define XENFEAT_not_direct_mapped         16
98 #define XENFEAT_direct_mapped             17
99 
100 #define XENFEAT_NR_SUBMAPS 1
101 
102 #endif /* __XEN_PUBLIC_FEATURES_H__ */
103