Commit | Line | Data |
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d2912cb1 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
0bf54fcd OP |
2 | /* |
3 | * ACPI configfs support | |
4 | * | |
5 | * Copyright (c) 2016 Intel Corporation | |
0bf54fcd OP |
6 | */ |
7 | ||
612bd01f OP |
8 | #define pr_fmt(fmt) "ACPI configfs: " fmt |
9 | ||
0bf54fcd OP |
10 | #include <linux/init.h> |
11 | #include <linux/module.h> | |
12 | #include <linux/configfs.h> | |
13 | #include <linux/acpi.h> | |
75b0cea7 | 14 | #include <linux/security.h> |
0bf54fcd | 15 | |
612bd01f OP |
16 | static struct config_group *acpi_table_group; |
17 | ||
18 | struct acpi_table { | |
19 | struct config_item cfg; | |
20 | struct acpi_table_header *header; | |
772bf1e2 | 21 | u32 index; |
612bd01f OP |
22 | }; |
23 | ||
24 | static ssize_t acpi_table_aml_write(struct config_item *cfg, | |
25 | const void *data, size_t size) | |
26 | { | |
27 | const struct acpi_table_header *header = data; | |
28 | struct acpi_table *table; | |
75b0cea7 JD |
29 | int ret = security_locked_down(LOCKDOWN_ACPI_TABLES); |
30 | ||
31 | if (ret) | |
32 | return ret; | |
612bd01f OP |
33 | |
34 | table = container_of(cfg, struct acpi_table, cfg); | |
35 | ||
36 | if (table->header) { | |
37 | pr_err("table already loaded\n"); | |
38 | return -EBUSY; | |
39 | } | |
40 | ||
41 | if (header->length != size) { | |
42 | pr_err("invalid table length\n"); | |
43 | return -EINVAL; | |
44 | } | |
45 | ||
46 | if (memcmp(header->signature, ACPI_SIG_SSDT, 4)) { | |
47 | pr_err("invalid table signature\n"); | |
48 | return -EINVAL; | |
49 | } | |
50 | ||
51 | table = container_of(cfg, struct acpi_table, cfg); | |
52 | ||
53 | table->header = kmemdup(header, header->length, GFP_KERNEL); | |
54 | if (!table->header) | |
55 | return -ENOMEM; | |
56 | ||
1770093c | 57 | ret = acpi_load_table(table->header, &table->index); |
612bd01f OP |
58 | if (ret) { |
59 | kfree(table->header); | |
60 | table->header = NULL; | |
61 | } | |
62 | ||
63 | return ret; | |
64 | } | |
65 | ||
66 | static inline struct acpi_table_header *get_header(struct config_item *cfg) | |
67 | { | |
68 | struct acpi_table *table = container_of(cfg, struct acpi_table, cfg); | |
69 | ||
70 | if (!table->header) | |
71 | pr_err("table not loaded\n"); | |
72 | ||
45c16fe1 | 73 | return table->header ?: ERR_PTR(-EINVAL); |
612bd01f OP |
74 | } |
75 | ||
76 | static ssize_t acpi_table_aml_read(struct config_item *cfg, | |
77 | void *data, size_t size) | |
78 | { | |
79 | struct acpi_table_header *h = get_header(cfg); | |
80 | ||
45c16fe1 AS |
81 | if (IS_ERR(h)) |
82 | return PTR_ERR(h); | |
612bd01f OP |
83 | |
84 | if (data) | |
85 | memcpy(data, h, h->length); | |
86 | ||
87 | return h->length; | |
88 | } | |
89 | ||
90 | #define MAX_ACPI_TABLE_SIZE (128 * 1024) | |
91 | ||
92 | CONFIGFS_BIN_ATTR(acpi_table_, aml, NULL, MAX_ACPI_TABLE_SIZE); | |
93 | ||
bf567dd3 | 94 | static struct configfs_bin_attribute *acpi_table_bin_attrs[] = { |
612bd01f OP |
95 | &acpi_table_attr_aml, |
96 | NULL, | |
97 | }; | |
98 | ||
c62c15a9 | 99 | static ssize_t acpi_table_signature_show(struct config_item *cfg, char *str) |
612bd01f OP |
100 | { |
101 | struct acpi_table_header *h = get_header(cfg); | |
102 | ||
45c16fe1 AS |
103 | if (IS_ERR(h)) |
104 | return PTR_ERR(h); | |
612bd01f | 105 | |
ae573387 | 106 | return sysfs_emit(str, "%.*s\n", ACPI_NAMESEG_SIZE, h->signature); |
612bd01f OP |
107 | } |
108 | ||
c62c15a9 | 109 | static ssize_t acpi_table_length_show(struct config_item *cfg, char *str) |
612bd01f OP |
110 | { |
111 | struct acpi_table_header *h = get_header(cfg); | |
112 | ||
45c16fe1 AS |
113 | if (IS_ERR(h)) |
114 | return PTR_ERR(h); | |
612bd01f | 115 | |
ae573387 | 116 | return sysfs_emit(str, "%d\n", h->length); |
612bd01f OP |
117 | } |
118 | ||
c62c15a9 | 119 | static ssize_t acpi_table_revision_show(struct config_item *cfg, char *str) |
612bd01f OP |
120 | { |
121 | struct acpi_table_header *h = get_header(cfg); | |
122 | ||
45c16fe1 AS |
123 | if (IS_ERR(h)) |
124 | return PTR_ERR(h); | |
612bd01f | 125 | |
ae573387 | 126 | return sysfs_emit(str, "%d\n", h->revision); |
612bd01f OP |
127 | } |
128 | ||
c62c15a9 | 129 | static ssize_t acpi_table_oem_id_show(struct config_item *cfg, char *str) |
612bd01f OP |
130 | { |
131 | struct acpi_table_header *h = get_header(cfg); | |
132 | ||
45c16fe1 AS |
133 | if (IS_ERR(h)) |
134 | return PTR_ERR(h); | |
612bd01f | 135 | |
ae573387 | 136 | return sysfs_emit(str, "%.*s\n", ACPI_OEM_ID_SIZE, h->oem_id); |
612bd01f OP |
137 | } |
138 | ||
c62c15a9 | 139 | static ssize_t acpi_table_oem_table_id_show(struct config_item *cfg, char *str) |
612bd01f OP |
140 | { |
141 | struct acpi_table_header *h = get_header(cfg); | |
142 | ||
45c16fe1 AS |
143 | if (IS_ERR(h)) |
144 | return PTR_ERR(h); | |
612bd01f | 145 | |
ae573387 | 146 | return sysfs_emit(str, "%.*s\n", ACPI_OEM_TABLE_ID_SIZE, h->oem_table_id); |
612bd01f OP |
147 | } |
148 | ||
c62c15a9 | 149 | static ssize_t acpi_table_oem_revision_show(struct config_item *cfg, char *str) |
612bd01f OP |
150 | { |
151 | struct acpi_table_header *h = get_header(cfg); | |
152 | ||
45c16fe1 AS |
153 | if (IS_ERR(h)) |
154 | return PTR_ERR(h); | |
612bd01f | 155 | |
ae573387 | 156 | return sysfs_emit(str, "%d\n", h->oem_revision); |
612bd01f OP |
157 | } |
158 | ||
c62c15a9 AS |
159 | static ssize_t acpi_table_asl_compiler_id_show(struct config_item *cfg, |
160 | char *str) | |
612bd01f OP |
161 | { |
162 | struct acpi_table_header *h = get_header(cfg); | |
163 | ||
45c16fe1 AS |
164 | if (IS_ERR(h)) |
165 | return PTR_ERR(h); | |
612bd01f | 166 | |
ae573387 | 167 | return sysfs_emit(str, "%.*s\n", ACPI_NAMESEG_SIZE, h->asl_compiler_id); |
612bd01f OP |
168 | } |
169 | ||
c62c15a9 AS |
170 | static ssize_t acpi_table_asl_compiler_revision_show(struct config_item *cfg, |
171 | char *str) | |
612bd01f OP |
172 | { |
173 | struct acpi_table_header *h = get_header(cfg); | |
174 | ||
45c16fe1 AS |
175 | if (IS_ERR(h)) |
176 | return PTR_ERR(h); | |
612bd01f | 177 | |
ae573387 | 178 | return sysfs_emit(str, "%d\n", h->asl_compiler_revision); |
612bd01f OP |
179 | } |
180 | ||
181 | CONFIGFS_ATTR_RO(acpi_table_, signature); | |
182 | CONFIGFS_ATTR_RO(acpi_table_, length); | |
183 | CONFIGFS_ATTR_RO(acpi_table_, revision); | |
184 | CONFIGFS_ATTR_RO(acpi_table_, oem_id); | |
185 | CONFIGFS_ATTR_RO(acpi_table_, oem_table_id); | |
186 | CONFIGFS_ATTR_RO(acpi_table_, oem_revision); | |
187 | CONFIGFS_ATTR_RO(acpi_table_, asl_compiler_id); | |
188 | CONFIGFS_ATTR_RO(acpi_table_, asl_compiler_revision); | |
189 | ||
bf567dd3 | 190 | static struct configfs_attribute *acpi_table_attrs[] = { |
612bd01f OP |
191 | &acpi_table_attr_signature, |
192 | &acpi_table_attr_length, | |
193 | &acpi_table_attr_revision, | |
194 | &acpi_table_attr_oem_id, | |
195 | &acpi_table_attr_oem_table_id, | |
196 | &acpi_table_attr_oem_revision, | |
197 | &acpi_table_attr_asl_compiler_id, | |
198 | &acpi_table_attr_asl_compiler_revision, | |
199 | NULL, | |
200 | }; | |
201 | ||
c1e95084 | 202 | static const struct config_item_type acpi_table_type = { |
612bd01f OP |
203 | .ct_owner = THIS_MODULE, |
204 | .ct_bin_attrs = acpi_table_bin_attrs, | |
205 | .ct_attrs = acpi_table_attrs, | |
206 | }; | |
207 | ||
208 | static struct config_item *acpi_table_make_item(struct config_group *group, | |
209 | const char *name) | |
210 | { | |
211 | struct acpi_table *table; | |
212 | ||
213 | table = kzalloc(sizeof(*table), GFP_KERNEL); | |
214 | if (!table) | |
215 | return ERR_PTR(-ENOMEM); | |
216 | ||
217 | config_item_init_type_name(&table->cfg, name, &acpi_table_type); | |
218 | return &table->cfg; | |
219 | } | |
220 | ||
772bf1e2 JK |
221 | static void acpi_table_drop_item(struct config_group *group, |
222 | struct config_item *cfg) | |
223 | { | |
224 | struct acpi_table *table = container_of(cfg, struct acpi_table, cfg); | |
225 | ||
be7ae568 | 226 | pr_debug("Host-directed Dynamic ACPI Table Unload\n"); |
1770093c | 227 | acpi_unload_table(table->index); |
9a2e849f | 228 | config_item_put(cfg); |
772bf1e2 JK |
229 | } |
230 | ||
bf567dd3 | 231 | static struct configfs_group_operations acpi_table_group_ops = { |
612bd01f | 232 | .make_item = acpi_table_make_item, |
772bf1e2 | 233 | .drop_item = acpi_table_drop_item, |
612bd01f OP |
234 | }; |
235 | ||
c1e95084 | 236 | static const struct config_item_type acpi_tables_type = { |
612bd01f OP |
237 | .ct_owner = THIS_MODULE, |
238 | .ct_group_ops = &acpi_table_group_ops, | |
239 | }; | |
240 | ||
c1e95084 | 241 | static const struct config_item_type acpi_root_group_type = { |
0bf54fcd OP |
242 | .ct_owner = THIS_MODULE, |
243 | }; | |
244 | ||
245 | static struct configfs_subsystem acpi_configfs = { | |
246 | .su_group = { | |
247 | .cg_item = { | |
248 | .ci_namebuf = "acpi", | |
249 | .ci_type = &acpi_root_group_type, | |
250 | }, | |
251 | }, | |
252 | .su_mutex = __MUTEX_INITIALIZER(acpi_configfs.su_mutex), | |
253 | }; | |
254 | ||
255 | static int __init acpi_configfs_init(void) | |
256 | { | |
257 | int ret; | |
258 | struct config_group *root = &acpi_configfs.su_group; | |
259 | ||
260 | config_group_init(root); | |
261 | ||
262 | ret = configfs_register_subsystem(&acpi_configfs); | |
263 | if (ret) | |
264 | return ret; | |
265 | ||
612bd01f OP |
266 | acpi_table_group = configfs_register_default_group(root, "table", |
267 | &acpi_tables_type); | |
67e40054 QM |
268 | if (IS_ERR(acpi_table_group)) { |
269 | configfs_unregister_subsystem(&acpi_configfs); | |
270 | return PTR_ERR(acpi_table_group); | |
271 | } | |
272 | ||
273 | return 0; | |
0bf54fcd OP |
274 | } |
275 | module_init(acpi_configfs_init); | |
276 | ||
277 | static void __exit acpi_configfs_exit(void) | |
278 | { | |
612bd01f | 279 | configfs_unregister_default_group(acpi_table_group); |
0bf54fcd OP |
280 | configfs_unregister_subsystem(&acpi_configfs); |
281 | } | |
282 | module_exit(acpi_configfs_exit); | |
283 | ||
284 | MODULE_AUTHOR("Octavian Purdila <octavian.purdila@intel.com>"); | |
285 | MODULE_DESCRIPTION("ACPI configfs support"); | |
286 | MODULE_LICENSE("GPL v2"); |