xref: /linux/include/xen/interface/elfnote.h (revision 3932b9ca55b0be314a36d3e84faff3e823c081f5)
1 /******************************************************************************
2  * elfnote.h
3  *
4  * Definitions used for the Xen ELF notes.
5  *
6  * Copyright (c) 2006, Ian Campbell, XenSource Ltd.
7  */
8 
9 #ifndef __XEN_PUBLIC_ELFNOTE_H__
10 #define __XEN_PUBLIC_ELFNOTE_H__
11 
12 /*
13  * The notes should live in a SHT_NOTE segment and have "Xen" in the
14  * name field.
15  *
16  * Numeric types are either 4 or 8 bytes depending on the content of
17  * the desc field.
18  *
19  * LEGACY indicated the fields in the legacy __xen_guest string which
20  * this a note type replaces.
21  */
22 
23 /*
24  * NAME=VALUE pair (string).
25  *
26  * LEGACY: FEATURES and PAE
27  */
28 #define XEN_ELFNOTE_INFO           0
29 
30 /*
31  * The virtual address of the entry point (numeric).
32  *
33  * LEGACY: VIRT_ENTRY
34  */
35 #define XEN_ELFNOTE_ENTRY          1
36 
37 /* The virtual address of the hypercall transfer page (numeric).
38  *
39  * LEGACY: HYPERCALL_PAGE. (n.b. legacy value is a physical page
40  * number not a virtual address)
41  */
42 #define XEN_ELFNOTE_HYPERCALL_PAGE 2
43 
44 /* The virtual address where the kernel image should be mapped (numeric).
45  *
46  * Defaults to 0.
47  *
48  * LEGACY: VIRT_BASE
49  */
50 #define XEN_ELFNOTE_VIRT_BASE      3
51 
52 /*
53  * The offset of the ELF paddr field from the acutal required
54  * pseudo-physical address (numeric).
55  *
56  * This is used to maintain backwards compatibility with older kernels
57  * which wrote __PAGE_OFFSET into that field. This field defaults to 0
58  * if not present.
59  *
60  * LEGACY: ELF_PADDR_OFFSET. (n.b. legacy default is VIRT_BASE)
61  */
62 #define XEN_ELFNOTE_PADDR_OFFSET   4
63 
64 /*
65  * The version of Xen that we work with (string).
66  *
67  * LEGACY: XEN_VER
68  */
69 #define XEN_ELFNOTE_XEN_VERSION    5
70 
71 /*
72  * The name of the guest operating system (string).
73  *
74  * LEGACY: GUEST_OS
75  */
76 #define XEN_ELFNOTE_GUEST_OS       6
77 
78 /*
79  * The version of the guest operating system (string).
80  *
81  * LEGACY: GUEST_VER
82  */
83 #define XEN_ELFNOTE_GUEST_VERSION  7
84 
85 /*
86  * The loader type (string).
87  *
88  * LEGACY: LOADER
89  */
90 #define XEN_ELFNOTE_LOADER         8
91 
92 /*
93  * The kernel supports PAE (x86/32 only, string = "yes" or "no").
94  *
95  * LEGACY: PAE (n.b. The legacy interface included a provision to
96  * indicate 'extended-cr3' support allowing L3 page tables to be
97  * placed above 4G. It is assumed that any kernel new enough to use
98  * these ELF notes will include this and therefore "yes" here is
99  * equivalent to "yes[entended-cr3]" in the __xen_guest interface.
100  */
101 #define XEN_ELFNOTE_PAE_MODE       9
102 
103 /*
104  * The features supported/required by this kernel (string).
105  *
106  * The string must consist of a list of feature names (as given in
107  * features.h, without the "XENFEAT_" prefix) separated by '|'
108  * characters. If a feature is required for the kernel to function
109  * then the feature name must be preceded by a '!' character.
110  *
111  * LEGACY: FEATURES
112  */
113 #define XEN_ELFNOTE_FEATURES      10
114 
115 /*
116  * The kernel requires the symbol table to be loaded (string = "yes" or "no")
117  * LEGACY: BSD_SYMTAB (n.b. The legacy treated the presence or absence
118  * of this string as a boolean flag rather than requiring "yes" or
119  * "no".
120  */
121 #define XEN_ELFNOTE_BSD_SYMTAB    11
122 
123 /*
124  * The lowest address the hypervisor hole can begin at (numeric).
125  *
126  * This must not be set higher than HYPERVISOR_VIRT_START. Its presence
127  * also indicates to the hypervisor that the kernel can deal with the
128  * hole starting at a higher address.
129  */
130 #define XEN_ELFNOTE_HV_START_LOW  12
131 
132 /*
133  * List of maddr_t-sized mask/value pairs describing how to recognize
134  * (non-present) L1 page table entries carrying valid MFNs (numeric).
135  */
136 #define XEN_ELFNOTE_L1_MFN_VALID  13
137 
138 /*
139  * Whether or not the guest supports cooperative suspend cancellation.
140  */
141 #define XEN_ELFNOTE_SUSPEND_CANCEL 14
142 
143 /*
144  * The features supported by this kernel (numeric).
145  *
146  * Other than XEN_ELFNOTE_FEATURES on pre-4.2 Xen, this note allows a
147  * kernel to specify support for features that older hypervisors don't
148  * know about. The set of features 4.2 and newer hypervisors will
149  * consider supported by the kernel is the combination of the sets
150  * specified through this and the string note.
151  *
152  * LEGACY: FEATURES
153  */
154 #define XEN_ELFNOTE_SUPPORTED_FEATURES 17
155 
156 #endif /* __XEN_PUBLIC_ELFNOTE_H__ */
157 
158 /*
159  * Local variables:
160  * mode: C
161  * c-set-style: "BSD"
162  * c-basic-offset: 4
163  * tab-width: 4
164  * indent-tabs-mode: nil
165  * End:
166  */
167