1/* SPDX-License-Identifier: GPL-2.0 */
2/******************************************************************************
3 * arch-x86_32.h
4 *
5 * Guest OS interface to x86 32-bit Xen.
6 *
7 * Copyright (c) 2004, K A Fraser
8 */
9
10#ifndef _ASM_X86_XEN_INTERFACE_32_H
11#define _ASM_X86_XEN_INTERFACE_32_H
12
13
14/*
15 * These flat segments are in the Xen-private section of every GDT. Since these
16 * are also present in the initial GDT, many OSes will be able to avoid
17 * installing their own GDT.
18 */
19#define FLAT_RING1_CS 0xe019    /* GDT index 259 */
20#define FLAT_RING1_DS 0xe021    /* GDT index 260 */
21#define FLAT_RING1_SS 0xe021    /* GDT index 260 */
22#define FLAT_RING3_CS 0xe02b    /* GDT index 261 */
23#define FLAT_RING3_DS 0xe033    /* GDT index 262 */
24#define FLAT_RING3_SS 0xe033    /* GDT index 262 */
25
26#define FLAT_KERNEL_CS FLAT_RING1_CS
27#define FLAT_KERNEL_DS FLAT_RING1_DS
28#define FLAT_KERNEL_SS FLAT_RING1_SS
29#define FLAT_USER_CS    FLAT_RING3_CS
30#define FLAT_USER_DS    FLAT_RING3_DS
31#define FLAT_USER_SS    FLAT_RING3_SS
32
33/* And the trap vector is... */
34#define TRAP_INSTR "int $0x82"
35
36#define __MACH2PHYS_VIRT_START 0xF5800000
37#define __MACH2PHYS_VIRT_END   0xF6800000
38
39#define __MACH2PHYS_SHIFT      2
40
41/*
42 * Virtual addresses beyond this are not modifiable by guest OSes. The
43 * machine->physical mapping table starts at this address, read-only.
44 */
45#define __HYPERVISOR_VIRT_START 0xF5800000
46
47#ifndef __ASSEMBLY__
48
49struct cpu_user_regs {
50    uint32_t ebx;
51    uint32_t ecx;
52    uint32_t edx;
53    uint32_t esi;
54    uint32_t edi;
55    uint32_t ebp;
56    uint32_t eax;
57    uint16_t error_code;    /* private */
58    uint16_t entry_vector;  /* private */
59    uint32_t eip;
60    uint16_t cs;
61    uint8_t  saved_upcall_mask;
62    uint8_t  _pad0;
63    uint32_t eflags;        /* eflags.IF == !saved_upcall_mask */
64    uint32_t esp;
65    uint16_t ss, _pad1;
66    uint16_t es, _pad2;
67    uint16_t ds, _pad3;
68    uint16_t fs, _pad4;
69    uint16_t gs, _pad5;
70};
71DEFINE_GUEST_HANDLE_STRUCT(cpu_user_regs);
72
73typedef uint64_t tsc_timestamp_t; /* RDTSC timestamp */
74
75struct arch_vcpu_info {
76    unsigned long cr2;
77    unsigned long pad[5]; /* sizeof(struct vcpu_info) == 64 */
78};
79
80struct xen_callback {
81	unsigned long cs;
82	unsigned long eip;
83};
84typedef struct xen_callback xen_callback_t;
85
86#define XEN_CALLBACK(__cs, __eip)				\
87	((struct xen_callback){ .cs = (__cs), .eip = (unsigned long)(__eip) })
88#endif /* !__ASSEMBLY__ */
89
90
91/*
92 * Page-directory addresses above 4GB do not fit into architectural %cr3.
93 * When accessing %cr3, or equivalent field in vcpu_guest_context, guests
94 * must use the following accessor macros to pack/unpack valid MFNs.
95 *
96 * Note that Xen is using the fact that the pagetable base is always
97 * page-aligned, and putting the 12 MSB of the address into the 12 LSB
98 * of cr3.
99 */
100#define xen_pfn_to_cr3(pfn) (((unsigned)(pfn) << 12) | ((unsigned)(pfn) >> 20))
101#define xen_cr3_to_pfn(cr3) (((unsigned)(cr3) >> 12) | ((unsigned)(cr3) << 20))
102
103#endif /* _ASM_X86_XEN_INTERFACE_32_H */
104