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