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

   1 /******************************************************************************
   2  * arch/ia64/xen/grant-table.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/module.h>
  24 #include <linux/vmalloc.h>
  25 #include <linux/slab.h>
  26 #include <linux/mm.h>
  27
  28 #include <xen/interface/xen.h>
  29 #include <xen/interface/memory.h>
  30 #include <xen/grant_table.h>
  31
  32 #include <asm/xen/hypervisor.h>
  33
  34 struct vm_struct *xen_alloc_vm_area(unsigned long size)
  35 {
  36         int order;
  37         unsigned long virt;
  38         unsigned long nr_pages;
  39         struct vm_struct *area;
  40
  41         order = get_order(size);
  42         virt = __get_free_pages(GFP_KERNEL, order);
  43         if (virt == 0)
  44                 goto err0;
  45         nr_pages = 1 << order;
  46         scrub_pages(virt, nr_pages);
  47
  48         area = kmalloc(sizeof(*area), GFP_KERNEL);
  49         if (area == NULL)
  50                 goto err1;
  51
  52         area->flags = VM_IOREMAP;
  53         area->addr = (void *)virt;
  54         area->size = size;
  55         area->pages = NULL;
  56         area->nr_pages = nr_pages;
  57         area->phys_addr = 0;    /* xenbus_map_ring_valloc uses this field!  */
  58
  59         return area;
  60
  61 err1:
  62         free_pages(virt, order);
  63 err0:
  64         return NULL;
  65 }
  66 EXPORT_SYMBOL_GPL(xen_alloc_vm_area);
  67
  68 void xen_free_vm_area(struct vm_struct *area)
  69 {
  70         unsigned int order = get_order(area->size);
  71         unsigned long i;
  72         unsigned long phys_addr = __pa(area->addr);
  73
  74         /* This area is used for foreign page mappping.
  75          * So underlying machine page may not be assigned. */
  76         for (i = 0; i < (1 << order); i++) {
  77                 unsigned long ret;
  78                 unsigned long gpfn = (phys_addr >> PAGE_SHIFT) + i;
  79                 struct xen_memory_reservation reservation = {
  80                         .nr_extents   = 1,
  81                         .address_bits = 0,
  82                         .extent_order = 0,
  83                         .domid        = DOMID_SELF
  84                 };
  85                 set_xen_guest_handle(reservation.extent_start, &gpfn);
  86                 ret = HYPERVISOR_memory_op(XENMEM_populate_physmap,
  87                                            &reservation);
  88                 BUG_ON(ret != 1);
  89         }
  90         free_pages((unsigned long)area->addr, order);
  91         kfree(area);
  92 }
  93 EXPORT_SYMBOL_GPL(xen_free_vm_area);
  94
  95
  96 /****************************************************************************
  97  * grant table hack
  98  * cmd: GNTTABOP_xxx
  99  */
 100
 101 int arch_gnttab_map_shared(unsigned long *frames, unsigned long nr_gframes,
 102                            unsigned long max_nr_gframes,
 103                            struct grant_entry **__shared)
 104 {
 105         *__shared = __va(frames[0] << PAGE_SHIFT);
 106         return 0;
 107 }
 108
 109 void arch_gnttab_unmap_shared(struct grant_entry *shared,
 110                               unsigned long nr_gframes)
 111 {
 112         /* nothing */
 113 }
 114
 115 static void
 116 gnttab_map_grant_ref_pre(struct gnttab_map_grant_ref *uop)
 117 {
 118         uint32_t flags;
 119
 120         flags = uop->flags;
 121
 122         if (flags & GNTMAP_host_map) {
 123                 if (flags & GNTMAP_application_map) {
 124                         printk(KERN_DEBUG
 125                                "GNTMAP_application_map is not supported yet: "
 126                                "flags 0x%x\n", flags);
 127                         BUG();
 128                 }
 129                 if (flags & GNTMAP_contains_pte) {
 130                         printk(KERN_DEBUG
 131                                "GNTMAP_contains_pte is not supported yet: "
 132                                "flags 0x%x\n", flags);
 133                         BUG();
 134                 }
 135         } else if (flags & GNTMAP_device_map) {
 136                 printk("GNTMAP_device_map is not supported yet 0x%x\n", flags);
 137                 BUG();  /* not yet. actually this flag is not used. */
 138         } else {
 139                 BUG();
 140         }
 141 }
 142
 143 int
 144 HYPERVISOR_grant_table_op(unsigned int cmd, void *uop, unsigned int count)
 145 {
 146         if (cmd == GNTTABOP_map_grant_ref) {
 147                 unsigned int i;
 148                 for (i = 0; i < count; i++) {
 149                         gnttab_map_grant_ref_pre(
 150                                 (struct gnttab_map_grant_ref *)uop + i);
 151                 }
 152         }
 153         return xencomm_hypercall_grant_table_op(cmd, uop, count);
 154 }
 155
 156 EXPORT_SYMBOL(HYPERVISOR_grant_table_op);