blob: 49ba9b5224d1a71da3b5d3dc139ca726f41bcd5e [file] [log] [blame]
Isaku Yamahata8d3d2102008-04-02 10:54:00 -07001/******************************************************************************
2 * grant_table.c
3 * x86 specific part
4 *
5 * Granting foreign access to our memory reservation.
6 *
7 * Copyright (c) 2005-2006, Christopher Clark
8 * Copyright (c) 2004-2005, K A Fraser
9 * Copyright (c) 2008 Isaku Yamahata <yamahata at valinux co jp>
10 * VA Linux Systems Japan. Split out x86 specific part.
11 *
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License version 2
14 * as published by the Free Software Foundation; or, when distributed
15 * separately from the Linux kernel or incorporated into other
16 * software packages, subject to the following license:
17 *
18 * Permission is hereby granted, free of charge, to any person obtaining a copy
19 * of this source file (the "Software"), to deal in the Software without
20 * restriction, including without limitation the rights to use, copy, modify,
21 * merge, publish, distribute, sublicense, and/or sell copies of the Software,
22 * and to permit persons to whom the Software is furnished to do so, subject to
23 * the following conditions:
24 *
25 * The above copyright notice and this permission notice shall be included in
26 * all copies or substantial portions of the Software.
27 *
28 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
29 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
30 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
31 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
32 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
33 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
34 * IN THE SOFTWARE.
35 */
36
37#include <linux/sched.h>
38#include <linux/mm.h>
39#include <linux/vmalloc.h>
40
41#include <xen/interface/xen.h>
42#include <xen/page.h>
43#include <xen/grant_table.h>
44
45#include <asm/pgtable.h>
46
47static int map_pte_fn(pte_t *pte, struct page *pmd_page,
48 unsigned long addr, void *data)
49{
50 unsigned long **frames = (unsigned long **)data;
51
52 set_pte_at(&init_mm, addr, pte, mfn_pte((*frames)[0], PAGE_KERNEL));
53 (*frames)++;
54 return 0;
55}
56
57static int unmap_pte_fn(pte_t *pte, struct page *pmd_page,
58 unsigned long addr, void *data)
59{
60
61 set_pte_at(&init_mm, addr, pte, __pte(0));
62 return 0;
63}
64
65int arch_gnttab_map_shared(unsigned long *frames, unsigned long nr_gframes,
66 unsigned long max_nr_gframes,
67 struct grant_entry **__shared)
68{
69 int rc;
70 struct grant_entry *shared = *__shared;
71
72 if (shared == NULL) {
73 struct vm_struct *area =
74 xen_alloc_vm_area(PAGE_SIZE * max_nr_gframes);
75 BUG_ON(area == NULL);
76 shared = area->addr;
77 *__shared = shared;
78 }
79
80 rc = apply_to_page_range(&init_mm, (unsigned long)shared,
81 PAGE_SIZE * nr_gframes,
82 map_pte_fn, &frames);
83 return rc;
84}
85
86void arch_gnttab_unmap_shared(struct grant_entry *shared,
87 unsigned long nr_gframes)
88{
89 apply_to_page_range(&init_mm, (unsigned long)shared,
90 PAGE_SIZE * nr_gframes, unmap_pte_fn, NULL);
91}