3 files changed, 655 insertions, 0 deletions

diff --git a/include/asm-i386/xen/hypercall.h b/include/asm-i386/xen/hypercall.h
new file mode 100644
index 000000000000..53912859708b
--- /dev/null
+++ b/include/asm-i386/xen/hypercall.h
@@ -0,0 +1,395 @@
+/******************************************************************************
+ * hypercall.h
+ *
+ * Linux-specific hypervisor handling.
+ *
+ * Copyright (c) 2002-2004, K A Fraser
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#ifndef __HYPERCALL_H__
+#define __HYPERCALL_H__
+
+#include <linux/errno.h>
+#include <linux/string.h>
+
+#include <xen/interface/xen.h>
+#include <xen/interface/sched.h>
+#include <xen/interface/physdev.h>
+
+extern struct { char _entry[32]; } hypercall_page[];
+
+#define _hypercall0(type, name)                                         \
+({                                                                      \
+        long __res;                                                     \
+        asm volatile (                                                  \
+                "call %[call]"                                          \
+                : "=a" (__res)                                          \
+                : [call] "m" (hypercall_page[__HYPERVISOR_##name])      \
+                : "memory" );                                           \
+        (type)__res;                                                    \
+})
+
+#define _hypercall1(type, name, a1)                                     \
+({                                                                      \
+        long __res, __ign1;                                             \
+        asm volatile (                                                  \
+                "call %[call]"                                          \
+                : "=a" (__res), "=b" (__ign1)                           \
+                : "1" ((long)(a1)),                                     \
+                  [call] "m" (hypercall_page[__HYPERVISOR_##name])      \
+                : "memory" );                                           \
+        (type)__res;                                                    \
+})
+
+#define _hypercall2(type, name, a1, a2)                                 \
+({                                                                      \
+        long __res, __ign1, __ign2;                                     \
+        asm volatile (                                                  \
+                "call %[call]"                                          \
+                : "=a" (__res), "=b" (__ign1), "=c" (__ign2)            \
+                : "1" ((long)(a1)), "2" ((long)(a2)),                   \
+                  [call] "m" (hypercall_page[__HYPERVISOR_##name])      \
+                : "memory" );                                           \
+        (type)__res;                                                    \
+})
+
+#define _hypercall3(type, name, a1, a2, a3)                             \
+({                                                                      \
+        long __res, __ign1, __ign2, __ign3;                             \
+        asm volatile (                                                  \
+                "call %[call]"                                          \
+                : "=a" (__res), "=b" (__ign1), "=c" (__ign2),           \
+                "=d" (__ign3)                                           \
+                : "1" ((long)(a1)), "2" ((long)(a2)),                   \
+                  "3" ((long)(a3)),                                     \
+                  [call] "m" (hypercall_page[__HYPERVISOR_##name])      \
+                : "memory" );                                           \
+        (type)__res;                                                    \
+})
+
+#define _hypercall4(type, name, a1, a2, a3, a4)                         \
+({                                                                      \
+        long __res, __ign1, __ign2, __ign3, __ign4;                     \
+        asm volatile (                                                  \
+                "call %[call]"                                          \
+                : "=a" (__res), "=b" (__ign1), "=c" (__ign2),           \
+                "=d" (__ign3), "=S" (__ign4)                            \
+                : "1" ((long)(a1)), "2" ((long)(a2)),                   \
+                  "3" ((long)(a3)), "4" ((long)(a4)),                   \
+                  [call] "m" (hypercall_page[__HYPERVISOR_##name])      \
+                : "memory" );                                           \
+        (type)__res;                                                    \
+})
+
+#define _hypercall5(type, name, a1, a2, a3, a4, a5)                     \
+({                                                                      \
+        long __res, __ign1, __ign2, __ign3, __ign4, __ign5;             \
+        asm volatile (                                                  \
+                "call %[call]"                                          \
+                : "=a" (__res), "=b" (__ign1), "=c" (__ign2),           \
+                "=d" (__ign3), "=S" (__ign4), "=D" (__ign5)             \
+                : "1" ((long)(a1)), "2" ((long)(a2)),                   \
+                  "3" ((long)(a3)), "4" ((long)(a4)),                   \
+                  "5" ((long)(a5)),                                     \
+                  [call] "m" (hypercall_page[__HYPERVISOR_##name])      \
+                : "memory" );                                           \
+        (type)__res;                                                    \
+})
+
+static inline int
+HYPERVISOR_set_trap_table(struct trap_info *table)
+{
+        return _hypercall1(int, set_trap_table, table);
+}
+
+static inline int
+HYPERVISOR_mmu_update(struct mmu_update *req, int count,
+                      int *success_count, domid_t domid)
+{
+        return _hypercall4(int, mmu_update, req, count, success_count, domid);
+}
+
+static inline int
+HYPERVISOR_mmuext_op(struct mmuext_op *op, int count,
+                     int *success_count, domid_t domid)
+{
+        return _hypercall4(int, mmuext_op, op, count, success_count, domid);
+}
+
+static inline int
+HYPERVISOR_set_gdt(unsigned long *frame_list, int entries)
+{
+        return _hypercall2(int, set_gdt, frame_list, entries);
+}
+
+static inline int
+HYPERVISOR_stack_switch(unsigned long ss, unsigned long esp)
+{
+        return _hypercall2(int, stack_switch, ss, esp);
+}
+
+static inline int
+HYPERVISOR_set_callbacks(unsigned long event_selector,
+                         unsigned long event_address,
+                         unsigned long failsafe_selector,
+                         unsigned long failsafe_address)
+{
+        return _hypercall4(int, set_callbacks,
+                           event_selector, event_address,
+                           failsafe_selector, failsafe_address);
+}
+
+static inline int
+HYPERVISOR_fpu_taskswitch(int set)
+{
+        return _hypercall1(int, fpu_taskswitch, set);
+}
+
+static inline int
+HYPERVISOR_sched_op(int cmd, unsigned long arg)
+{
+        return _hypercall2(int, sched_op, cmd, arg);
+}
+
+static inline long
+HYPERVISOR_set_timer_op(u64 timeout)
+{
+        unsigned long timeout_hi = (unsigned long)(timeout>>32);
+        unsigned long timeout_lo = (unsigned long)timeout;
+        return _hypercall2(long, set_timer_op, timeout_lo, timeout_hi);
+}
+
+static inline int
+HYPERVISOR_set_debugreg(int reg, unsigned long value)
+{
+        return _hypercall2(int, set_debugreg, reg, value);
+}
+
+static inline unsigned long
+HYPERVISOR_get_debugreg(int reg)
+{
+        return _hypercall1(unsigned long, get_debugreg, reg);
+}
+
+static inline int
+HYPERVISOR_update_descriptor(u64 ma, u64 desc)
+{
+        return _hypercall4(int, update_descriptor, ma, ma>>32, desc, desc>>32);
+}
+
+static inline int
+HYPERVISOR_memory_op(unsigned int cmd, void *arg)
+{
+        return _hypercall2(int, memory_op, cmd, arg);
+}
+
+static inline int
+HYPERVISOR_multicall(void *call_list, int nr_calls)
+{
+        return _hypercall2(int, multicall, call_list, nr_calls);
+}
+
+static inline int
+HYPERVISOR_update_va_mapping(unsigned long va, pte_t new_val,
+                             unsigned long flags)
+{
+        unsigned long pte_hi = 0;
+#ifdef CONFIG_X86_PAE
+        pte_hi = new_val.pte_high;
+#endif
+        return _hypercall4(int, update_va_mapping, va,
+                           new_val.pte_low, pte_hi, flags);
+}
+
+static inline int
+HYPERVISOR_event_channel_op(int cmd, void *arg)
+{
+        int rc = _hypercall2(int, event_channel_op, cmd, arg);
+        if (unlikely(rc == -ENOSYS)) {
+                struct evtchn_op op;
+                op.cmd = cmd;
+                memcpy(&op.u, arg, sizeof(op.u));
+                rc = _hypercall1(int, event_channel_op_compat, &op);
+                memcpy(arg, &op.u, sizeof(op.u));
+        }
+        return rc;
+}
+
+static inline int
+HYPERVISOR_xen_version(int cmd, void *arg)
+{
+        return _hypercall2(int, xen_version, cmd, arg);
+}
+
+static inline int
+HYPERVISOR_console_io(int cmd, int count, char *str)
+{
+        return _hypercall3(int, console_io, cmd, count, str);
+}
+
+static inline int
+HYPERVISOR_physdev_op(int cmd, void *arg)
+{
+        int rc = _hypercall2(int, physdev_op, cmd, arg);
+        if (unlikely(rc == -ENOSYS)) {
+                struct physdev_op op;
+                op.cmd = cmd;
+                memcpy(&op.u, arg, sizeof(op.u));
+                rc = _hypercall1(int, physdev_op_compat, &op);
+                memcpy(arg, &op.u, sizeof(op.u));
+        }
+        return rc;
+}
+
+static inline int
+HYPERVISOR_grant_table_op(unsigned int cmd, void *uop, unsigned int count)
+{
+        return _hypercall3(int, grant_table_op, cmd, uop, count);
+}
+
+static inline int
+HYPERVISOR_update_va_mapping_otherdomain(unsigned long va, pte_t new_val,
+                                         unsigned long flags, domid_t domid)
+{
+        unsigned long pte_hi = 0;
+#ifdef CONFIG_X86_PAE
+        pte_hi = new_val.pte_high;
+#endif
+        return _hypercall5(int, update_va_mapping_otherdomain, va,
+                           new_val.pte_low, pte_hi, flags, domid);
+}
+
+static inline int
+HYPERVISOR_vm_assist(unsigned int cmd, unsigned int type)
+{
+        return _hypercall2(int, vm_assist, cmd, type);
+}
+
+static inline int
+HYPERVISOR_vcpu_op(int cmd, int vcpuid, void *extra_args)
+{
+        return _hypercall3(int, vcpu_op, cmd, vcpuid, extra_args);
+}
+
+static inline int
+HYPERVISOR_suspend(unsigned long srec)
+{
+        return _hypercall3(int, sched_op, SCHEDOP_shutdown,
+                           SHUTDOWN_suspend, srec);
+}
+
+static inline int
+HYPERVISOR_nmi_op(unsigned long op, unsigned long arg)
+{
+        return _hypercall2(int, nmi_op, op, arg);
+}
+
+static inline void
+MULTI_update_va_mapping(struct multicall_entry *mcl, unsigned long va,
+                        pte_t new_val, unsigned long flags)
+{
+        mcl->op = __HYPERVISOR_update_va_mapping;
+        mcl->args[0] = va;
+#ifdef CONFIG_X86_PAE
+        mcl->args[1] = new_val.pte_low;
+        mcl->args[2] = new_val.pte_high;
+#else
+        mcl->args[1] = new_val.pte_low;
+        mcl->args[2] = 0;
+#endif
+        mcl->args[3] = flags;
+}
+
+static inline void
+MULTI_grant_table_op(struct multicall_entry *mcl, unsigned int cmd,
+                     void *uop, unsigned int count)
+{
+        mcl->op = __HYPERVISOR_grant_table_op;
+        mcl->args[0] = cmd;
+        mcl->args[1] = (unsigned long)uop;
+        mcl->args[2] = count;
+}
+
+static inline void
+MULTI_update_va_mapping_otherdomain(struct multicall_entry *mcl, unsigned long va,
+                                    pte_t new_val, unsigned long flags,
+                                    domid_t domid)
+{
+        mcl->op = __HYPERVISOR_update_va_mapping_otherdomain;
+        mcl->args[0] = va;
+#ifdef CONFIG_X86_PAE
+        mcl->args[1] = new_val.pte_low;
+        mcl->args[2] = new_val.pte_high;
+#else
+        mcl->args[1] = new_val.pte_low;
+        mcl->args[2] = 0;
+#endif
+        mcl->args[3] = flags;
+        mcl->args[4] = domid;
+}
+
+static inline void
+MULTI_update_descriptor(struct multicall_entry *mcl, u64 maddr,
+                        struct desc_struct desc)
+{
+        mcl->op = __HYPERVISOR_update_descriptor;
+        mcl->args[0] = maddr;
+        mcl->args[1] = maddr >> 32;
+        mcl->args[2] = desc.a;
+        mcl->args[3] = desc.b;
+}
+
+static inline void
+MULTI_memory_op(struct multicall_entry *mcl, unsigned int cmd, void *arg)
+{
+        mcl->op = __HYPERVISOR_memory_op;
+        mcl->args[0] = cmd;
+        mcl->args[1] = (unsigned long)arg;
+}
+
+static inline void
+MULTI_mmu_update(struct multicall_entry *mcl, struct mmu_update *req,
+                 int count, int *success_count, domid_t domid)
+{
+        mcl->op = __HYPERVISOR_mmu_update;
+        mcl->args[0] = (unsigned long)req;
+        mcl->args[1] = count;
+        mcl->args[2] = (unsigned long)success_count;
+        mcl->args[3] = domid;
+}
+
+static inline void
+MULTI_mmuext_op(struct multicall_entry *mcl, struct mmuext_op *op, int count,
+                int *success_count, domid_t domid)
+{
+        mcl->op = __HYPERVISOR_mmuext_op;
+        mcl->args[0] = (unsigned long)op;
+        mcl->args[1] = count;
+        mcl->args[2] = (unsigned long)success_count;
+        mcl->args[3] = domid;
+}
+#endif /* __HYPERCALL_H__ */
diff --git a/include/asm-i386/xen/hypervisor.h b/include/asm-i386/xen/hypervisor.h
new file mode 100644
index 000000000000..ebfa7e063088
--- /dev/null
+++ b/include/asm-i386/xen/hypervisor.h
@@ -0,0 +1,72 @@
+/******************************************************************************
+ * hypervisor.h
+ *
+ * Linux-specific hypervisor handling.
+ *
+ * Copyright (c) 2002-2004, K A Fraser
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#ifndef __HYPERVISOR_H__
+#define __HYPERVISOR_H__
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/version.h>
+
+#include <xen/interface/xen.h>
+#include <xen/interface/version.h>
+
+#include <asm/ptrace.h>
+#include <asm/page.h>
+#if defined(__i386__)
+#  ifdef CONFIG_X86_PAE
+#   include <asm-generic/pgtable-nopud.h>
+#  else
+#   include <asm-generic/pgtable-nopmd.h>
+#  endif
+#endif
+#include <asm/xen/hypercall.h>
+
+/* arch/i386/kernel/setup.c */
+extern struct shared_info *HYPERVISOR_shared_info;
+extern struct start_info *xen_start_info;
+#define is_initial_xendomain() (xen_start_info->flags & SIF_INITDOMAIN)
+
+/* arch/i386/mach-xen/evtchn.c */
+/* Force a proper event-channel callback from Xen. */
+extern void force_evtchn_callback(void);
+
+/* Turn jiffies into Xen system time. */
+u64 jiffies_to_st(unsigned long jiffies);
+
+
+#define MULTI_UVMFLAGS_INDEX 3
+#define MULTI_UVMDOMID_INDEX 4
+
+#define is_running_on_xen()     (xen_start_info ? 1 : 0)
+
+#endif /* __HYPERVISOR_H__ */
diff --git a/include/asm-i386/xen/interface.h b/include/asm-i386/xen/interface.h
new file mode 100644
index 000000000000..165c3968e138
--- /dev/null
+++ b/include/asm-i386/xen/interface.h
@@ -0,0 +1,188 @@
+/******************************************************************************
+ * arch-x86_32.h
+ *
+ * Guest OS interface to x86 32-bit Xen.
+ *
+ * Copyright (c) 2004, K A Fraser
+ */
+
+#ifndef __XEN_PUBLIC_ARCH_X86_32_H__
+#define __XEN_PUBLIC_ARCH_X86_32_H__
+
+#ifdef __XEN__
+#define __DEFINE_GUEST_HANDLE(name, type) \
+    typedef struct { type *p; } __guest_handle_ ## name
+#else
+#define __DEFINE_GUEST_HANDLE(name, type) \
+    typedef type * __guest_handle_ ## name
+#endif
+
+#define DEFINE_GUEST_HANDLE_STRUCT(name) \
+        __DEFINE_GUEST_HANDLE(name, struct name)
+#define DEFINE_GUEST_HANDLE(name) __DEFINE_GUEST_HANDLE(name, name)
+#define GUEST_HANDLE(name)        __guest_handle_ ## name
+
+#ifndef __ASSEMBLY__
+/* Guest handles for primitive C types. */
+__DEFINE_GUEST_HANDLE(uchar, unsigned char);
+__DEFINE_GUEST_HANDLE(uint,  unsigned int);
+__DEFINE_GUEST_HANDLE(ulong, unsigned long);
+DEFINE_GUEST_HANDLE(char);
+DEFINE_GUEST_HANDLE(int);
+DEFINE_GUEST_HANDLE(long);
+DEFINE_GUEST_HANDLE(void);
+#endif
+
+/*
+ * SEGMENT DESCRIPTOR TABLES
+ */
+/*
+ * A number of GDT entries are reserved by Xen. These are not situated at the
+ * start of the GDT because some stupid OSes export hard-coded selector values
+ * in their ABI. These hard-coded values are always near the start of the GDT,
+ * so Xen places itself out of the way, at the far end of the GDT.
+ */
+#define FIRST_RESERVED_GDT_PAGE  14
+#define FIRST_RESERVED_GDT_BYTE  (FIRST_RESERVED_GDT_PAGE * 4096)
+#define FIRST_RESERVED_GDT_ENTRY (FIRST_RESERVED_GDT_BYTE / 8)
+
+/*
+ * These flat segments are in the Xen-private section of every GDT. Since these
+ * are also present in the initial GDT, many OSes will be able to avoid
+ * installing their own GDT.
+ */
+#define FLAT_RING1_CS 0xe019    /* GDT index 259 */
+#define FLAT_RING1_DS 0xe021    /* GDT index 260 */
+#define FLAT_RING1_SS 0xe021    /* GDT index 260 */
+#define FLAT_RING3_CS 0xe02b    /* GDT index 261 */
+#define FLAT_RING3_DS 0xe033    /* GDT index 262 */
+#define FLAT_RING3_SS 0xe033    /* GDT index 262 */
+
+#define FLAT_KERNEL_CS FLAT_RING1_CS
+#define FLAT_KERNEL_DS FLAT_RING1_DS
+#define FLAT_KERNEL_SS FLAT_RING1_SS
+#define FLAT_USER_CS    FLAT_RING3_CS
+#define FLAT_USER_DS    FLAT_RING3_DS
+#define FLAT_USER_SS    FLAT_RING3_SS
+
+/* And the trap vector is... */
+#define TRAP_INSTR "int $0x82"
+
+/*
+ * Virtual addresses beyond this are not modifiable by guest OSes. The
+ * machine->physical mapping table starts at this address, read-only.
+ */
+#ifdef CONFIG_X86_PAE
+#define __HYPERVISOR_VIRT_START 0xF5800000
+#else
+#define __HYPERVISOR_VIRT_START 0xFC000000
+#endif
+
+#ifndef HYPERVISOR_VIRT_START
+#define HYPERVISOR_VIRT_START mk_unsigned_long(__HYPERVISOR_VIRT_START)
+#endif
+
+#ifndef machine_to_phys_mapping
+#define machine_to_phys_mapping ((unsigned long *)HYPERVISOR_VIRT_START)
+#endif
+
+/* Maximum number of virtual CPUs in multi-processor guests. */
+#define MAX_VIRT_CPUS 32
+
+#ifndef __ASSEMBLY__
+
+/*
+ * Send an array of these to HYPERVISOR_set_trap_table()
+ */
+#define TI_GET_DPL(_ti)         ((_ti)->flags & 3)
+#define TI_GET_IF(_ti)          ((_ti)->flags & 4)
+#define TI_SET_DPL(_ti, _dpl)   ((_ti)->flags |= (_dpl))
+#define TI_SET_IF(_ti, _if)     ((_ti)->flags |= ((!!(_if))<<2))
+
+struct trap_info {
+    uint8_t       vector;  /* exception vector                              */
+    uint8_t       flags;   /* 0-3: privilege level; 4: clear event enable?  */
+    uint16_t      cs;      /* code selector                                 */
+    unsigned long address; /* code offset                                   */
+};
+DEFINE_GUEST_HANDLE_STRUCT(trap_info);
+
+struct cpu_user_regs {
+    uint32_t ebx;
+    uint32_t ecx;
+    uint32_t edx;
+    uint32_t esi;
+    uint32_t edi;
+    uint32_t ebp;
+    uint32_t eax;
+    uint16_t error_code;    /* private */
+    uint16_t entry_vector;  /* private */
+    uint32_t eip;
+    uint16_t cs;
+    uint8_t  saved_upcall_mask;
+    uint8_t  _pad0;
+    uint32_t eflags;        /* eflags.IF == !saved_upcall_mask */
+    uint32_t esp;
+    uint16_t ss, _pad1;
+    uint16_t es, _pad2;
+    uint16_t ds, _pad3;
+    uint16_t fs, _pad4;
+    uint16_t gs, _pad5;
+};
+DEFINE_GUEST_HANDLE_STRUCT(cpu_user_regs);
+
+typedef uint64_t tsc_timestamp_t; /* RDTSC timestamp */
+
+/*
+ * The following is all CPU context. Note that the fpu_ctxt block is filled
+ * in by FXSAVE if the CPU has feature FXSR; otherwise FSAVE is used.
+ */
+struct vcpu_guest_context {
+    /* FPU registers come first so they can be aligned for FXSAVE/FXRSTOR. */
+    struct { char x[512]; } fpu_ctxt;       /* User-level FPU registers     */
+#define VGCF_I387_VALID (1<<0)
+#define VGCF_HVM_GUEST  (1<<1)
+#define VGCF_IN_KERNEL  (1<<2)
+    unsigned long flags;                    /* VGCF_* flags                 */
+    struct cpu_user_regs user_regs;         /* User-level CPU registers     */
+    struct trap_info trap_ctxt[256];        /* Virtual IDT                  */
+    unsigned long ldt_base, ldt_ents;       /* LDT (linear address, # ents) */
+    unsigned long gdt_frames[16], gdt_ents; /* GDT (machine frames, # ents) */
+    unsigned long kernel_ss, kernel_sp;     /* Virtual TSS (only SS1/SP1)   */
+    unsigned long ctrlreg[8];               /* CR0-CR7 (control registers)  */
+    unsigned long debugreg[8];              /* DB0-DB7 (debug registers)    */
+    unsigned long event_callback_cs;        /* CS:EIP of event callback     */
+    unsigned long event_callback_eip;
+    unsigned long failsafe_callback_cs;     /* CS:EIP of failsafe callback  */
+    unsigned long failsafe_callback_eip;
+    unsigned long vm_assist;                /* VMASST_TYPE_* bitmap */
+};
+DEFINE_GUEST_HANDLE_STRUCT(vcpu_guest_context);
+
+struct arch_shared_info {
+    unsigned long max_pfn;                  /* max pfn that appears in table */
+    /* Frame containing list of mfns containing list of mfns containing p2m. */
+    unsigned long pfn_to_mfn_frame_list_list;
+    unsigned long nmi_reason;
+};
+
+struct arch_vcpu_info {
+    unsigned long cr2;
+    unsigned long pad[5]; /* sizeof(struct vcpu_info) == 64 */
+};
+
+#endif /* !__ASSEMBLY__ */
+
+/*
+ * Prefix forces emulation of some non-trapping instructions.
+ * Currently only CPUID.
+ */
+#ifdef __ASSEMBLY__
+#define XEN_EMULATE_PREFIX .byte 0x0f,0x0b,0x78,0x65,0x6e ;
+#define XEN_CPUID          XEN_EMULATE_PREFIX cpuid
+#else
+#define XEN_EMULATE_PREFIX ".byte 0x0f,0x0b,0x78,0x65,0x6e ; "
+#define XEN_CPUID          XEN_EMULATE_PREFIX "cpuid"
+#endif
+
+#endif