1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
|
/******************************************************************************
* grant_table.c
* x86 specific part
*
* Granting foreign access to our memory reservation.
*
* Copyright (c) 2005-2006, Christopher Clark
* Copyright (c) 2004-2005, K A Fraser
* Copyright (c) 2008 Isaku Yamahata <yamahata at valinux co jp>
* VA Linux Systems Japan. Split out x86 specific part.
*
* 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.
*/
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/vmalloc.h>
#include <xen/interface/xen.h>
#include <xen/page.h>
#include <xen/grant_table.h>
#include <asm/pgtable.h>
static int map_pte_fn(pte_t *pte, struct page *pmd_page,
unsigned long addr, void *data)
{
unsigned long **frames = (unsigned long **)data;
set_pte_at(&init_mm, addr, pte, mfn_pte((*frames)[0], PAGE_KERNEL));
(*frames)++;
return 0;
}
/*
* This function is used to map shared frames to store grant status. It is
* different from map_pte_fn above, the frames type here is uint64_t.
*/
static int map_pte_fn_status(pte_t *pte, struct page *pmd_page,
unsigned long addr, void *data)
{
uint64_t **frames = (uint64_t **)data;
set_pte_at(&init_mm, addr, pte, mfn_pte((*frames)[0], PAGE_KERNEL));
(*frames)++;
return 0;
}
static int unmap_pte_fn(pte_t *pte, struct page *pmd_page,
unsigned long addr, void *data)
{
set_pte_at(&init_mm, addr, pte, __pte(0));
return 0;
}
int arch_gnttab_map_shared(unsigned long *frames, unsigned long nr_gframes,
unsigned long max_nr_gframes,
void **__shared)
{
int rc;
void *shared = *__shared;
if (shared == NULL) {
struct vm_struct *area =
alloc_vm_area(PAGE_SIZE * max_nr_gframes, NULL);
BUG_ON(area == NULL);
shared = area->addr;
*__shared = shared;
}
rc = apply_to_page_range(&init_mm, (unsigned long)shared,
PAGE_SIZE * nr_gframes,
map_pte_fn, &frames);
return rc;
}
int arch_gnttab_map_status(uint64_t *frames, unsigned long nr_gframes,
unsigned long max_nr_gframes,
grant_status_t **__shared)
{
int rc;
grant_status_t *shared = *__shared;
if (shared == NULL) {
/* No need to pass in PTE as we are going to do it
* in apply_to_page_range anyhow. */
struct vm_struct *area =
alloc_vm_area(PAGE_SIZE * max_nr_gframes, NULL);
BUG_ON(area == NULL);
shared = area->addr;
*__shared = shared;
}
rc = apply_to_page_range(&init_mm, (unsigned long)shared,
PAGE_SIZE * nr_gframes,
map_pte_fn_status, &frames);
return rc;
}
void arch_gnttab_unmap(void *shared, unsigned long nr_gframes)
{
apply_to_page_range(&init_mm, (unsigned long)shared,
PAGE_SIZE * nr_gframes, unmap_pte_fn, NULL);
}
#ifdef CONFIG_XEN_PVH
#include <xen/balloon.h>
#include <xen/events.h>
#include <xen/xen.h>
#include <linux/slab.h>
static int __init xlated_setup_gnttab_pages(void)
{
struct page **pages;
xen_pfn_t *pfns;
int rc;
unsigned int i;
unsigned long nr_grant_frames = gnttab_max_grant_frames();
BUG_ON(nr_grant_frames == 0);
pages = kcalloc(nr_grant_frames, sizeof(pages[0]), GFP_KERNEL);
if (!pages)
return -ENOMEM;
pfns = kcalloc(nr_grant_frames, sizeof(pfns[0]), GFP_KERNEL);
if (!pfns) {
kfree(pages);
return -ENOMEM;
}
rc = alloc_xenballooned_pages(nr_grant_frames, pages, 0 /* lowmem */);
if (rc) {
pr_warn("%s Couldn't balloon alloc %ld pfns rc:%d\n", __func__,
nr_grant_frames, rc);
kfree(pages);
kfree(pfns);
return rc;
}
for (i = 0; i < nr_grant_frames; i++)
pfns[i] = page_to_pfn(pages[i]);
rc = arch_gnttab_map_shared(pfns, nr_grant_frames, nr_grant_frames,
&xen_auto_xlat_grant_frames.vaddr);
if (rc) {
pr_warn("%s Couldn't map %ld pfns rc:%d\n", __func__,
nr_grant_frames, rc);
free_xenballooned_pages(nr_grant_frames, pages);
kfree(pages);
kfree(pfns);
return rc;
}
kfree(pages);
xen_auto_xlat_grant_frames.pfn = pfns;
xen_auto_xlat_grant_frames.count = nr_grant_frames;
return 0;
}
static int __init xen_pvh_gnttab_setup(void)
{
if (!xen_pvh_domain())
return -ENODEV;
return xlated_setup_gnttab_pages();
}
/* Call it _before_ __gnttab_init as we need to initialize the
* xen_auto_xlat_grant_frames first. */
core_initcall(xen_pvh_gnttab_setup);
#endif
|
