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
|
// SPDX-License-Identifier: GPL-2.0
/*
* CMA DebugFS Interface
*
* Copyright (c) 2015 Sasha Levin <sasha.levin@oracle.com>
*/
#include <linux/debugfs.h>
#include <linux/cma.h>
#include <linux/list.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/mm_types.h>
#include "cma.h"
struct cma_mem {
struct hlist_node node;
struct page *p;
unsigned long n;
};
static int cma_debugfs_get(void *data, u64 *val)
{
unsigned long *p = data;
*val = *p;
return 0;
}
DEFINE_SIMPLE_ATTRIBUTE(cma_debugfs_fops, cma_debugfs_get, NULL, "%llu\n");
static int cma_used_get(void *data, u64 *val)
{
struct cma *cma = data;
unsigned long used;
mutex_lock(&cma->lock);
/* pages counter is smaller than sizeof(int) */
used = bitmap_weight(cma->bitmap, (int)cma_bitmap_maxno(cma));
mutex_unlock(&cma->lock);
*val = (u64)used << cma->order_per_bit;
return 0;
}
DEFINE_SIMPLE_ATTRIBUTE(cma_used_fops, cma_used_get, NULL, "%llu\n");
static int cma_maxchunk_get(void *data, u64 *val)
{
struct cma *cma = data;
unsigned long maxchunk = 0;
unsigned long start, end = 0;
unsigned long bitmap_maxno = cma_bitmap_maxno(cma);
mutex_lock(&cma->lock);
for (;;) {
start = find_next_zero_bit(cma->bitmap, bitmap_maxno, end);
if (start >= bitmap_maxno)
break;
end = find_next_bit(cma->bitmap, bitmap_maxno, start);
maxchunk = max(end - start, maxchunk);
}
mutex_unlock(&cma->lock);
*val = (u64)maxchunk << cma->order_per_bit;
return 0;
}
DEFINE_SIMPLE_ATTRIBUTE(cma_maxchunk_fops, cma_maxchunk_get, NULL, "%llu\n");
static void cma_add_to_cma_mem_list(struct cma *cma, struct cma_mem *mem)
{
spin_lock(&cma->mem_head_lock);
hlist_add_head(&mem->node, &cma->mem_head);
spin_unlock(&cma->mem_head_lock);
}
static struct cma_mem *cma_get_entry_from_list(struct cma *cma)
{
struct cma_mem *mem = NULL;
spin_lock(&cma->mem_head_lock);
if (!hlist_empty(&cma->mem_head)) {
mem = hlist_entry(cma->mem_head.first, struct cma_mem, node);
hlist_del_init(&mem->node);
}
spin_unlock(&cma->mem_head_lock);
return mem;
}
static int cma_free_mem(struct cma *cma, int count)
{
struct cma_mem *mem = NULL;
while (count) {
mem = cma_get_entry_from_list(cma);
if (mem == NULL)
return 0;
if (mem->n <= count) {
cma_release(cma, mem->p, mem->n);
count -= mem->n;
kfree(mem);
} else if (cma->order_per_bit == 0) {
cma_release(cma, mem->p, count);
mem->p += count;
mem->n -= count;
count = 0;
cma_add_to_cma_mem_list(cma, mem);
} else {
pr_debug("cma: cannot release partial block when order_per_bit != 0\n");
cma_add_to_cma_mem_list(cma, mem);
break;
}
}
return 0;
}
static int cma_free_write(void *data, u64 val)
{
int pages = val;
struct cma *cma = data;
return cma_free_mem(cma, pages);
}
DEFINE_SIMPLE_ATTRIBUTE(cma_free_fops, NULL, cma_free_write, "%llu\n");
static int cma_alloc_mem(struct cma *cma, int count)
{
struct cma_mem *mem;
struct page *p;
mem = kzalloc(sizeof(*mem), GFP_KERNEL);
if (!mem)
return -ENOMEM;
p = cma_alloc(cma, count, 0, false);
if (!p) {
kfree(mem);
return -ENOMEM;
}
mem->p = p;
mem->n = count;
cma_add_to_cma_mem_list(cma, mem);
return 0;
}
static int cma_alloc_write(void *data, u64 val)
{
int pages = val;
struct cma *cma = data;
return cma_alloc_mem(cma, pages);
}
DEFINE_SIMPLE_ATTRIBUTE(cma_alloc_fops, NULL, cma_alloc_write, "%llu\n");
static void cma_debugfs_add_one(struct cma *cma, struct dentry *root_dentry)
{
struct dentry *tmp;
char name[16];
int u32s;
scnprintf(name, sizeof(name), "cma-%s", cma->name);
tmp = debugfs_create_dir(name, root_dentry);
debugfs_create_file("alloc", 0200, tmp, cma, &cma_alloc_fops);
debugfs_create_file("free", 0200, tmp, cma, &cma_free_fops);
debugfs_create_file("base_pfn", 0444, tmp,
&cma->base_pfn, &cma_debugfs_fops);
debugfs_create_file("count", 0444, tmp, &cma->count, &cma_debugfs_fops);
debugfs_create_file("order_per_bit", 0444, tmp,
&cma->order_per_bit, &cma_debugfs_fops);
debugfs_create_file("used", 0444, tmp, cma, &cma_used_fops);
debugfs_create_file("maxchunk", 0444, tmp, cma, &cma_maxchunk_fops);
u32s = DIV_ROUND_UP(cma_bitmap_maxno(cma), BITS_PER_BYTE * sizeof(u32));
debugfs_create_u32_array("bitmap", 0444, tmp, (u32 *)cma->bitmap, u32s);
}
static int __init cma_debugfs_init(void)
{
struct dentry *cma_debugfs_root;
int i;
cma_debugfs_root = debugfs_create_dir("cma", NULL);
for (i = 0; i < cma_area_count; i++)
cma_debugfs_add_one(&cma_areas[i], cma_debugfs_root);
return 0;
}
late_initcall(cma_debugfs_init);
|
