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 */