release/src-rt-6.x.4708/linux/linux-2.6.36/arch/ia64/xen/hypervisor.c

   1 /******************************************************************************
   2  * arch/ia64/xen/hypervisor.c
   3  *
   4  * Copyright (c) 2006 Isaku Yamahata <yamahata at valinux co jp>
   5  *                    VA Linux Systems Japan K.K.
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  *
  21  */
  22
  23 #include <linux/efi.h>
  24 #include <asm/xen/hypervisor.h>
  25 #include <asm/xen/privop.h>
  26
  27 #include "irq_xen.h"
  28
  29 struct shared_info *HYPERVISOR_shared_info __read_mostly =
  30         (struct shared_info *)XSI_BASE;
  31 EXPORT_SYMBOL(HYPERVISOR_shared_info);
  32
  33 DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu);
  34
  35 struct start_info *xen_start_info;
  36 EXPORT_SYMBOL(xen_start_info);
  37
  38 EXPORT_SYMBOL(xen_domain_type);
  39
  40 EXPORT_SYMBOL(__hypercall);
  41
  42 /* Stolen from arch/x86/xen/enlighten.c */
  43 /*
  44  * Flag to determine whether vcpu info placement is available on all
  45  * VCPUs.  We assume it is to start with, and then set it to zero on
  46  * the first failure.  This is because it can succeed on some VCPUs
  47  * and not others, since it can involve hypervisor memory allocation,
  48  * or because the guest failed to guarantee all the appropriate
  49  * constraints on all VCPUs (ie buffer can't cross a page boundary).
  50  *
  51  * Note that any particular CPU may be using a placed vcpu structure,
  52  * but we can only optimise if the all are.
  53  *
  54  * 0: not available, 1: available
  55  */
  56
  57 static void __init xen_vcpu_setup(int cpu)
  58 {
  59         /*
  60          * WARNING:
  61          * before changing MAX_VIRT_CPUS,
  62          * check that shared_info fits on a page
  63          */
  64         BUILD_BUG_ON(sizeof(struct shared_info) > PAGE_SIZE);
  65         per_cpu(xen_vcpu, cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu];
  66 }
  67
  68 void __init xen_setup_vcpu_info_placement(void)
  69 {
  70         int cpu;
  71
  72         for_each_possible_cpu(cpu)
  73                 xen_vcpu_setup(cpu);
  74 }
  75
  76 void __cpuinit
  77 xen_cpu_init(void)
  78 {
  79         xen_smp_intr_init();
  80 }
  81
  82 /**************************************************************************
  83  * opt feature
  84  */
  85 void
  86 xen_ia64_enable_opt_feature(void)
  87 {
  88         /* Enable region 7 identity map optimizations in Xen */
  89         struct xen_ia64_opt_feature optf;
  90
  91         optf.cmd = XEN_IA64_OPTF_IDENT_MAP_REG7;
  92         optf.on = XEN_IA64_OPTF_ON;
  93         optf.pgprot = pgprot_val(PAGE_KERNEL);
  94         optf.key = 0;   /* No key on linux. */
  95         HYPERVISOR_opt_feature(&optf);
  96 }