blob: c970792b11a48cb8d0e7f2191c1155205de6dcfb [file] [log] [blame]
Thomas Gleixnerd2912cb2019-06-04 10:11:33 +02001// SPDX-License-Identifier: GPL-2.0-only
Octavian Purdila0bf54fc2016-07-08 19:13:13 +03002/*
3 * ACPI configfs support
4 *
5 * Copyright (c) 2016 Intel Corporation
Octavian Purdila0bf54fc2016-07-08 19:13:13 +03006 */
7
Octavian Purdila612bd012016-07-08 19:13:14 +03008#define pr_fmt(fmt) "ACPI configfs: " fmt
9
Octavian Purdila0bf54fc2016-07-08 19:13:13 +030010#include <linux/init.h>
11#include <linux/module.h>
12#include <linux/configfs.h>
13#include <linux/acpi.h>
Jason A. Donenfeld75b0cea2020-06-15 04:43:32 -060014#include <linux/security.h>
Octavian Purdila0bf54fc2016-07-08 19:13:13 +030015
Octavian Purdila612bd012016-07-08 19:13:14 +030016static struct config_group *acpi_table_group;
17
18struct acpi_table {
19 struct config_item cfg;
20 struct acpi_table_header *header;
Jan Kiszka772bf1e2017-06-09 20:36:31 +020021 u32 index;
Octavian Purdila612bd012016-07-08 19:13:14 +030022};
23
24static 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;
Jason A. Donenfeld75b0cea2020-06-15 04:43:32 -060029 int ret = security_locked_down(LOCKDOWN_ACPI_TABLES);
30
31 if (ret)
32 return ret;
Octavian Purdila612bd012016-07-08 19:13:14 +030033
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
Nikolaus Voss17700932019-10-25 14:36:53 -070057 ret = acpi_load_table(table->header, &table->index);
Octavian Purdila612bd012016-07-08 19:13:14 +030058 if (ret) {
59 kfree(table->header);
60 table->header = NULL;
61 }
62
63 return ret;
64}
65
66static 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
Andy Shevchenko45c16fe2021-07-15 17:16:51 +030073 return table->header ?: ERR_PTR(-EINVAL);
Octavian Purdila612bd012016-07-08 19:13:14 +030074}
75
76static 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
Andy Shevchenko45c16fe2021-07-15 17:16:51 +030081 if (IS_ERR(h))
82 return PTR_ERR(h);
Octavian Purdila612bd012016-07-08 19:13:14 +030083
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
92CONFIGFS_BIN_ATTR(acpi_table_, aml, NULL, MAX_ACPI_TABLE_SIZE);
93
Andy Shevchenkobf567dd2019-03-11 16:04:30 +020094static struct configfs_bin_attribute *acpi_table_bin_attrs[] = {
Octavian Purdila612bd012016-07-08 19:13:14 +030095 &acpi_table_attr_aml,
96 NULL,
97};
98
Andy Shevchenkoc62c15a2019-03-11 16:04:29 +020099static ssize_t acpi_table_signature_show(struct config_item *cfg, char *str)
Octavian Purdila612bd012016-07-08 19:13:14 +0300100{
101 struct acpi_table_header *h = get_header(cfg);
102
Andy Shevchenko45c16fe2021-07-15 17:16:51 +0300103 if (IS_ERR(h))
104 return PTR_ERR(h);
Octavian Purdila612bd012016-07-08 19:13:14 +0300105
Andy Shevchenkoae573382021-07-15 17:16:50 +0300106 return sysfs_emit(str, "%.*s\n", ACPI_NAMESEG_SIZE, h->signature);
Octavian Purdila612bd012016-07-08 19:13:14 +0300107}
108
Andy Shevchenkoc62c15a2019-03-11 16:04:29 +0200109static ssize_t acpi_table_length_show(struct config_item *cfg, char *str)
Octavian Purdila612bd012016-07-08 19:13:14 +0300110{
111 struct acpi_table_header *h = get_header(cfg);
112
Andy Shevchenko45c16fe2021-07-15 17:16:51 +0300113 if (IS_ERR(h))
114 return PTR_ERR(h);
Octavian Purdila612bd012016-07-08 19:13:14 +0300115
Andy Shevchenkoae573382021-07-15 17:16:50 +0300116 return sysfs_emit(str, "%d\n", h->length);
Octavian Purdila612bd012016-07-08 19:13:14 +0300117}
118
Andy Shevchenkoc62c15a2019-03-11 16:04:29 +0200119static ssize_t acpi_table_revision_show(struct config_item *cfg, char *str)
Octavian Purdila612bd012016-07-08 19:13:14 +0300120{
121 struct acpi_table_header *h = get_header(cfg);
122
Andy Shevchenko45c16fe2021-07-15 17:16:51 +0300123 if (IS_ERR(h))
124 return PTR_ERR(h);
Octavian Purdila612bd012016-07-08 19:13:14 +0300125
Andy Shevchenkoae573382021-07-15 17:16:50 +0300126 return sysfs_emit(str, "%d\n", h->revision);
Octavian Purdila612bd012016-07-08 19:13:14 +0300127}
128
Andy Shevchenkoc62c15a2019-03-11 16:04:29 +0200129static ssize_t acpi_table_oem_id_show(struct config_item *cfg, char *str)
Octavian Purdila612bd012016-07-08 19:13:14 +0300130{
131 struct acpi_table_header *h = get_header(cfg);
132
Andy Shevchenko45c16fe2021-07-15 17:16:51 +0300133 if (IS_ERR(h))
134 return PTR_ERR(h);
Octavian Purdila612bd012016-07-08 19:13:14 +0300135
Andy Shevchenkoae573382021-07-15 17:16:50 +0300136 return sysfs_emit(str, "%.*s\n", ACPI_OEM_ID_SIZE, h->oem_id);
Octavian Purdila612bd012016-07-08 19:13:14 +0300137}
138
Andy Shevchenkoc62c15a2019-03-11 16:04:29 +0200139static ssize_t acpi_table_oem_table_id_show(struct config_item *cfg, char *str)
Octavian Purdila612bd012016-07-08 19:13:14 +0300140{
141 struct acpi_table_header *h = get_header(cfg);
142
Andy Shevchenko45c16fe2021-07-15 17:16:51 +0300143 if (IS_ERR(h))
144 return PTR_ERR(h);
Octavian Purdila612bd012016-07-08 19:13:14 +0300145
Andy Shevchenkoae573382021-07-15 17:16:50 +0300146 return sysfs_emit(str, "%.*s\n", ACPI_OEM_TABLE_ID_SIZE, h->oem_table_id);
Octavian Purdila612bd012016-07-08 19:13:14 +0300147}
148
Andy Shevchenkoc62c15a2019-03-11 16:04:29 +0200149static ssize_t acpi_table_oem_revision_show(struct config_item *cfg, char *str)
Octavian Purdila612bd012016-07-08 19:13:14 +0300150{
151 struct acpi_table_header *h = get_header(cfg);
152
Andy Shevchenko45c16fe2021-07-15 17:16:51 +0300153 if (IS_ERR(h))
154 return PTR_ERR(h);
Octavian Purdila612bd012016-07-08 19:13:14 +0300155
Andy Shevchenkoae573382021-07-15 17:16:50 +0300156 return sysfs_emit(str, "%d\n", h->oem_revision);
Octavian Purdila612bd012016-07-08 19:13:14 +0300157}
158
Andy Shevchenkoc62c15a2019-03-11 16:04:29 +0200159static ssize_t acpi_table_asl_compiler_id_show(struct config_item *cfg,
160 char *str)
Octavian Purdila612bd012016-07-08 19:13:14 +0300161{
162 struct acpi_table_header *h = get_header(cfg);
163
Andy Shevchenko45c16fe2021-07-15 17:16:51 +0300164 if (IS_ERR(h))
165 return PTR_ERR(h);
Octavian Purdila612bd012016-07-08 19:13:14 +0300166
Andy Shevchenkoae573382021-07-15 17:16:50 +0300167 return sysfs_emit(str, "%.*s\n", ACPI_NAMESEG_SIZE, h->asl_compiler_id);
Octavian Purdila612bd012016-07-08 19:13:14 +0300168}
169
Andy Shevchenkoc62c15a2019-03-11 16:04:29 +0200170static ssize_t acpi_table_asl_compiler_revision_show(struct config_item *cfg,
171 char *str)
Octavian Purdila612bd012016-07-08 19:13:14 +0300172{
173 struct acpi_table_header *h = get_header(cfg);
174
Andy Shevchenko45c16fe2021-07-15 17:16:51 +0300175 if (IS_ERR(h))
176 return PTR_ERR(h);
Octavian Purdila612bd012016-07-08 19:13:14 +0300177
Andy Shevchenkoae573382021-07-15 17:16:50 +0300178 return sysfs_emit(str, "%d\n", h->asl_compiler_revision);
Octavian Purdila612bd012016-07-08 19:13:14 +0300179}
180
181CONFIGFS_ATTR_RO(acpi_table_, signature);
182CONFIGFS_ATTR_RO(acpi_table_, length);
183CONFIGFS_ATTR_RO(acpi_table_, revision);
184CONFIGFS_ATTR_RO(acpi_table_, oem_id);
185CONFIGFS_ATTR_RO(acpi_table_, oem_table_id);
186CONFIGFS_ATTR_RO(acpi_table_, oem_revision);
187CONFIGFS_ATTR_RO(acpi_table_, asl_compiler_id);
188CONFIGFS_ATTR_RO(acpi_table_, asl_compiler_revision);
189
Andy Shevchenkobf567dd2019-03-11 16:04:30 +0200190static struct configfs_attribute *acpi_table_attrs[] = {
Octavian Purdila612bd012016-07-08 19:13:14 +0300191 &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
Bhumika Goyalc1e95082017-10-16 17:18:48 +0200202static const struct config_item_type acpi_table_type = {
Octavian Purdila612bd012016-07-08 19:13:14 +0300203 .ct_owner = THIS_MODULE,
204 .ct_bin_attrs = acpi_table_bin_attrs,
205 .ct_attrs = acpi_table_attrs,
206};
207
208static 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
Jan Kiszka772bf1e2017-06-09 20:36:31 +0200221static 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
Hanjun Guobe7ae562021-05-24 17:41:05 +0800226 pr_debug("Host-directed Dynamic ACPI Table Unload\n");
Nikolaus Voss17700932019-10-25 14:36:53 -0700227 acpi_unload_table(table->index);
Hanjun Guo9a2e8492020-09-18 17:13:28 +0800228 config_item_put(cfg);
Jan Kiszka772bf1e2017-06-09 20:36:31 +0200229}
230
Andy Shevchenkobf567dd2019-03-11 16:04:30 +0200231static struct configfs_group_operations acpi_table_group_ops = {
Octavian Purdila612bd012016-07-08 19:13:14 +0300232 .make_item = acpi_table_make_item,
Jan Kiszka772bf1e2017-06-09 20:36:31 +0200233 .drop_item = acpi_table_drop_item,
Octavian Purdila612bd012016-07-08 19:13:14 +0300234};
235
Bhumika Goyalc1e95082017-10-16 17:18:48 +0200236static const struct config_item_type acpi_tables_type = {
Octavian Purdila612bd012016-07-08 19:13:14 +0300237 .ct_owner = THIS_MODULE,
238 .ct_group_ops = &acpi_table_group_ops,
239};
240
Bhumika Goyalc1e95082017-10-16 17:18:48 +0200241static const struct config_item_type acpi_root_group_type = {
Octavian Purdila0bf54fc2016-07-08 19:13:13 +0300242 .ct_owner = THIS_MODULE,
243};
244
245static 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
255static 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
Octavian Purdila612bd012016-07-08 19:13:14 +0300266 acpi_table_group = configfs_register_default_group(root, "table",
267 &acpi_tables_type);
Qinglang Miao67e40052021-01-15 10:22:50 +0800268 if (IS_ERR(acpi_table_group)) {
269 configfs_unregister_subsystem(&acpi_configfs);
270 return PTR_ERR(acpi_table_group);
271 }
272
273 return 0;
Octavian Purdila0bf54fc2016-07-08 19:13:13 +0300274}
275module_init(acpi_configfs_init);
276
277static void __exit acpi_configfs_exit(void)
278{
Octavian Purdila612bd012016-07-08 19:13:14 +0300279 configfs_unregister_default_group(acpi_table_group);
Octavian Purdila0bf54fc2016-07-08 19:13:13 +0300280 configfs_unregister_subsystem(&acpi_configfs);
281}
282module_exit(acpi_configfs_exit);
283
284MODULE_AUTHOR("Octavian Purdila <octavian.purdila@intel.com>");
285MODULE_DESCRIPTION("ACPI configfs support");
286MODULE_LICENSE("GPL v2");