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