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
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
|
// SPDX-License-Identifier: GPL-2.0-only
#include <linux/memblock.h>
#include <linux/gfp.h>
#include <linux/export.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/dma-mapping.h>
#include <linux/vmalloc.h>
#include <linux/swiotlb.h>
#include <xen/xen.h>
#include <xen/interface/memory.h>
#include <xen/page.h>
#include <xen/swiotlb-xen.h>
#include <asm/cacheflush.h>
#include <asm/xen/hypercall.h>
#include <asm/xen/interface.h>
struct xen_p2m_entry {
unsigned long pfn;
unsigned long mfn;
unsigned long nr_pages;
struct rb_node rbnode_phys;
};
static rwlock_t p2m_lock;
struct rb_root phys_to_mach = RB_ROOT;
EXPORT_SYMBOL_GPL(phys_to_mach);
static int xen_add_phys_to_mach_entry(struct xen_p2m_entry *new)
{
struct rb_node **link = &phys_to_mach.rb_node;
struct rb_node *parent = NULL;
struct xen_p2m_entry *entry;
int rc = 0;
while (*link) {
parent = *link;
entry = rb_entry(parent, struct xen_p2m_entry, rbnode_phys);
if (new->pfn == entry->pfn)
goto err_out;
if (new->pfn < entry->pfn)
link = &(*link)->rb_left;
else
link = &(*link)->rb_right;
}
rb_link_node(&new->rbnode_phys, parent, link);
rb_insert_color(&new->rbnode_phys, &phys_to_mach);
goto out;
err_out:
rc = -EINVAL;
pr_warn("%s: cannot add pfn=%pa -> mfn=%pa: pfn=%pa -> mfn=%pa already exists\n",
__func__, &new->pfn, &new->mfn, &entry->pfn, &entry->mfn);
out:
return rc;
}
unsigned long __pfn_to_mfn(unsigned long pfn)
{
struct rb_node *n;
struct xen_p2m_entry *entry;
unsigned long irqflags;
read_lock_irqsave(&p2m_lock, irqflags);
n = phys_to_mach.rb_node;
while (n) {
entry = rb_entry(n, struct xen_p2m_entry, rbnode_phys);
if (entry->pfn <= pfn &&
entry->pfn + entry->nr_pages > pfn) {
unsigned long mfn = entry->mfn + (pfn - entry->pfn);
read_unlock_irqrestore(&p2m_lock, irqflags);
return mfn;
}
if (pfn < entry->pfn)
n = n->rb_left;
else
n = n->rb_right;
}
read_unlock_irqrestore(&p2m_lock, irqflags);
return INVALID_P2M_ENTRY;
}
EXPORT_SYMBOL_GPL(__pfn_to_mfn);
int set_foreign_p2m_mapping(struct gnttab_map_grant_ref *map_ops,
struct gnttab_map_grant_ref *kmap_ops,
struct page **pages, unsigned int count)
{
int i;
for (i = 0; i < count; i++) {
struct gnttab_unmap_grant_ref unmap;
int rc;
if (map_ops[i].status)
continue;
if (likely(set_phys_to_machine(map_ops[i].host_addr >> XEN_PAGE_SHIFT,
map_ops[i].dev_bus_addr >> XEN_PAGE_SHIFT)))
continue;
/*
* Signal an error for this slot. This in turn requires
* immediate unmapping.
*/
map_ops[i].status = GNTST_general_error;
unmap.host_addr = map_ops[i].host_addr,
unmap.handle = map_ops[i].handle;
map_ops[i].handle = ~0;
if (map_ops[i].flags & GNTMAP_device_map)
unmap.dev_bus_addr = map_ops[i].dev_bus_addr;
else
unmap.dev_bus_addr = 0;
/*
* Pre-populate the status field, to be recognizable in
* the log message below.
*/
unmap.status = 1;
rc = HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref,
&unmap, 1);
if (rc || unmap.status != GNTST_okay)
pr_err_once("gnttab unmap failed: rc=%d st=%d\n",
rc, unmap.status);
}
return 0;
}
EXPORT_SYMBOL_GPL(set_foreign_p2m_mapping);
int clear_foreign_p2m_mapping(struct gnttab_unmap_grant_ref *unmap_ops,
struct gnttab_unmap_grant_ref *kunmap_ops,
struct page **pages, unsigned int count)
{
int i;
for (i = 0; i < count; i++) {
set_phys_to_machine(unmap_ops[i].host_addr >> XEN_PAGE_SHIFT,
INVALID_P2M_ENTRY);
}
return 0;
}
EXPORT_SYMBOL_GPL(clear_foreign_p2m_mapping);
bool __set_phys_to_machine_multi(unsigned long pfn,
unsigned long mfn, unsigned long nr_pages)
{
int rc;
unsigned long irqflags;
struct xen_p2m_entry *p2m_entry;
struct rb_node *n;
if (mfn == INVALID_P2M_ENTRY) {
write_lock_irqsave(&p2m_lock, irqflags);
n = phys_to_mach.rb_node;
while (n) {
p2m_entry = rb_entry(n, struct xen_p2m_entry, rbnode_phys);
if (p2m_entry->pfn <= pfn &&
p2m_entry->pfn + p2m_entry->nr_pages > pfn) {
rb_erase(&p2m_entry->rbnode_phys, &phys_to_mach);
write_unlock_irqrestore(&p2m_lock, irqflags);
kfree(p2m_entry);
return true;
}
if (pfn < p2m_entry->pfn)
n = n->rb_left;
else
n = n->rb_right;
}
write_unlock_irqrestore(&p2m_lock, irqflags);
return true;
}
p2m_entry = kzalloc(sizeof(*p2m_entry), GFP_NOWAIT);
if (!p2m_entry)
return false;
p2m_entry->pfn = pfn;
p2m_entry->nr_pages = nr_pages;
p2m_entry->mfn = mfn;
write_lock_irqsave(&p2m_lock, irqflags);
rc = xen_add_phys_to_mach_entry(p2m_entry);
if (rc < 0) {
write_unlock_irqrestore(&p2m_lock, irqflags);
kfree(p2m_entry);
return false;
}
write_unlock_irqrestore(&p2m_lock, irqflags);
return true;
}
EXPORT_SYMBOL_GPL(__set_phys_to_machine_multi);
bool __set_phys_to_machine(unsigned long pfn, unsigned long mfn)
{
return __set_phys_to_machine_multi(pfn, mfn, 1);
}
EXPORT_SYMBOL_GPL(__set_phys_to_machine);
static int p2m_init(void)
{
rwlock_init(&p2m_lock);
return 0;
}
arch_initcall(p2m_init);
|
