Commit | Line | Data |
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28b24c1f SL |
1 | /* |
2 | * CMA DebugFS Interface | |
3 | * | |
4 | * Copyright (c) 2015 Sasha Levin <sasha.levin@oracle.com> | |
5 | */ | |
6 | ||
7 | ||
8 | #include <linux/debugfs.h> | |
9 | #include <linux/cma.h> | |
26b02a1f SL |
10 | #include <linux/list.h> |
11 | #include <linux/kernel.h> | |
12 | #include <linux/slab.h> | |
8325330b | 13 | #include <linux/mm_types.h> |
28b24c1f SL |
14 | |
15 | #include "cma.h" | |
16 | ||
26b02a1f SL |
17 | struct cma_mem { |
18 | struct hlist_node node; | |
19 | struct page *p; | |
20 | unsigned long n; | |
21 | }; | |
22 | ||
28b24c1f SL |
23 | static struct dentry *cma_debugfs_root; |
24 | ||
25 | static int cma_debugfs_get(void *data, u64 *val) | |
26 | { | |
27 | unsigned long *p = data; | |
28 | ||
29 | *val = *p; | |
30 | ||
31 | return 0; | |
32 | } | |
28b24c1f SL |
33 | DEFINE_SIMPLE_ATTRIBUTE(cma_debugfs_fops, cma_debugfs_get, NULL, "%llu\n"); |
34 | ||
2e32b947 DS |
35 | static int cma_used_get(void *data, u64 *val) |
36 | { | |
37 | struct cma *cma = data; | |
38 | unsigned long used; | |
39 | ||
40 | mutex_lock(&cma->lock); | |
41 | /* pages counter is smaller than sizeof(int) */ | |
42 | used = bitmap_weight(cma->bitmap, (int)cma->count); | |
43 | mutex_unlock(&cma->lock); | |
44 | *val = (u64)used << cma->order_per_bit; | |
45 | ||
46 | return 0; | |
47 | } | |
2e32b947 DS |
48 | DEFINE_SIMPLE_ATTRIBUTE(cma_used_fops, cma_used_get, NULL, "%llu\n"); |
49 | ||
50 | static int cma_maxchunk_get(void *data, u64 *val) | |
51 | { | |
52 | struct cma *cma = data; | |
53 | unsigned long maxchunk = 0; | |
54 | unsigned long start, end = 0; | |
55 | ||
56 | mutex_lock(&cma->lock); | |
57 | for (;;) { | |
58 | start = find_next_zero_bit(cma->bitmap, cma->count, end); | |
59 | if (start >= cma->count) | |
60 | break; | |
61 | end = find_next_bit(cma->bitmap, cma->count, start); | |
62 | maxchunk = max(end - start, maxchunk); | |
63 | } | |
64 | mutex_unlock(&cma->lock); | |
65 | *val = (u64)maxchunk << cma->order_per_bit; | |
66 | ||
67 | return 0; | |
68 | } | |
2e32b947 DS |
69 | DEFINE_SIMPLE_ATTRIBUTE(cma_maxchunk_fops, cma_maxchunk_get, NULL, "%llu\n"); |
70 | ||
26b02a1f SL |
71 | static void cma_add_to_cma_mem_list(struct cma *cma, struct cma_mem *mem) |
72 | { | |
73 | spin_lock(&cma->mem_head_lock); | |
74 | hlist_add_head(&mem->node, &cma->mem_head); | |
75 | spin_unlock(&cma->mem_head_lock); | |
76 | } | |
77 | ||
8325330b SL |
78 | static struct cma_mem *cma_get_entry_from_list(struct cma *cma) |
79 | { | |
80 | struct cma_mem *mem = NULL; | |
81 | ||
82 | spin_lock(&cma->mem_head_lock); | |
83 | if (!hlist_empty(&cma->mem_head)) { | |
84 | mem = hlist_entry(cma->mem_head.first, struct cma_mem, node); | |
85 | hlist_del_init(&mem->node); | |
86 | } | |
87 | spin_unlock(&cma->mem_head_lock); | |
88 | ||
89 | return mem; | |
90 | } | |
91 | ||
92 | static int cma_free_mem(struct cma *cma, int count) | |
93 | { | |
94 | struct cma_mem *mem = NULL; | |
95 | ||
96 | while (count) { | |
97 | mem = cma_get_entry_from_list(cma); | |
98 | if (mem == NULL) | |
99 | return 0; | |
100 | ||
101 | if (mem->n <= count) { | |
102 | cma_release(cma, mem->p, mem->n); | |
103 | count -= mem->n; | |
104 | kfree(mem); | |
105 | } else if (cma->order_per_bit == 0) { | |
106 | cma_release(cma, mem->p, count); | |
107 | mem->p += count; | |
108 | mem->n -= count; | |
109 | count = 0; | |
110 | cma_add_to_cma_mem_list(cma, mem); | |
111 | } else { | |
112 | pr_debug("cma: cannot release partial block when order_per_bit != 0\n"); | |
113 | cma_add_to_cma_mem_list(cma, mem); | |
114 | break; | |
115 | } | |
116 | } | |
117 | ||
118 | return 0; | |
119 | ||
120 | } | |
121 | ||
122 | static int cma_free_write(void *data, u64 val) | |
123 | { | |
124 | int pages = val; | |
125 | struct cma *cma = data; | |
126 | ||
127 | return cma_free_mem(cma, pages); | |
128 | } | |
8325330b SL |
129 | DEFINE_SIMPLE_ATTRIBUTE(cma_free_fops, NULL, cma_free_write, "%llu\n"); |
130 | ||
26b02a1f SL |
131 | static int cma_alloc_mem(struct cma *cma, int count) |
132 | { | |
133 | struct cma_mem *mem; | |
134 | struct page *p; | |
135 | ||
136 | mem = kzalloc(sizeof(*mem), GFP_KERNEL); | |
137 | if (!mem) | |
138 | return -ENOMEM; | |
139 | ||
875abdb6 | 140 | p = cma_alloc(cma, count, 0); |
26b02a1f SL |
141 | if (!p) { |
142 | kfree(mem); | |
143 | return -ENOMEM; | |
144 | } | |
145 | ||
146 | mem->p = p; | |
147 | mem->n = count; | |
148 | ||
149 | cma_add_to_cma_mem_list(cma, mem); | |
150 | ||
151 | return 0; | |
152 | } | |
153 | ||
154 | static int cma_alloc_write(void *data, u64 val) | |
155 | { | |
156 | int pages = val; | |
157 | struct cma *cma = data; | |
158 | ||
159 | return cma_alloc_mem(cma, pages); | |
160 | } | |
26b02a1f SL |
161 | DEFINE_SIMPLE_ATTRIBUTE(cma_alloc_fops, NULL, cma_alloc_write, "%llu\n"); |
162 | ||
28b24c1f SL |
163 | static void cma_debugfs_add_one(struct cma *cma, int idx) |
164 | { | |
165 | struct dentry *tmp; | |
166 | char name[16]; | |
167 | int u32s; | |
168 | ||
169 | sprintf(name, "cma-%d", idx); | |
170 | ||
171 | tmp = debugfs_create_dir(name, cma_debugfs_root); | |
172 | ||
26b02a1f SL |
173 | debugfs_create_file("alloc", S_IWUSR, cma_debugfs_root, cma, |
174 | &cma_alloc_fops); | |
175 | ||
8325330b SL |
176 | debugfs_create_file("free", S_IWUSR, cma_debugfs_root, cma, |
177 | &cma_free_fops); | |
178 | ||
28b24c1f SL |
179 | debugfs_create_file("base_pfn", S_IRUGO, tmp, |
180 | &cma->base_pfn, &cma_debugfs_fops); | |
181 | debugfs_create_file("count", S_IRUGO, tmp, | |
182 | &cma->count, &cma_debugfs_fops); | |
183 | debugfs_create_file("order_per_bit", S_IRUGO, tmp, | |
26b02a1f | 184 | &cma->order_per_bit, &cma_debugfs_fops); |
2e32b947 DS |
185 | debugfs_create_file("used", S_IRUGO, tmp, cma, &cma_used_fops); |
186 | debugfs_create_file("maxchunk", S_IRUGO, tmp, cma, &cma_maxchunk_fops); | |
28b24c1f SL |
187 | |
188 | u32s = DIV_ROUND_UP(cma_bitmap_maxno(cma), BITS_PER_BYTE * sizeof(u32)); | |
189 | debugfs_create_u32_array("bitmap", S_IRUGO, tmp, (u32*)cma->bitmap, u32s); | |
190 | } | |
191 | ||
192 | static int __init cma_debugfs_init(void) | |
193 | { | |
194 | int i; | |
195 | ||
196 | cma_debugfs_root = debugfs_create_dir("cma", NULL); | |
197 | if (!cma_debugfs_root) | |
198 | return -ENOMEM; | |
199 | ||
200 | for (i = 0; i < cma_area_count; i++) | |
201 | cma_debugfs_add_one(&cma_areas[i], i); | |
202 | ||
203 | return 0; | |
204 | } | |
205 | late_initcall(cma_debugfs_init); |