// SPDX-License-Identifier: GPL-2.0-only /* * ACPI configfs support * * Copyright (c) 2016 Intel Corporation */ #define pr_fmt(fmt) "ACPI configfs: " fmt #include #include #include #include #include "acpica/accommon.h" #include "acpica/actables.h" static struct config_group *acpi_table_group; struct acpi_table { struct config_item cfg; struct acpi_table_header *header; u32 index; }; static ssize_t acpi_table_aml_write(struct config_item *cfg, const void *data, size_t size) { const struct acpi_table_header *header = data; struct acpi_table *table; int ret; table = container_of(cfg, struct acpi_table, cfg); if (table->header) { pr_err("table already loaded\n"); return -EBUSY; } if (header->length != size) { pr_err("invalid table length\n"); return -EINVAL; } if (memcmp(header->signature, ACPI_SIG_SSDT, 4)) { pr_err("invalid table signature\n"); return -EINVAL; } table = container_of(cfg, struct acpi_table, cfg); table->header = kmemdup(header, header->length, GFP_KERNEL); if (!table->header) return -ENOMEM; ret = acpi_load_table(table->header, &table->index); if (ret) { kfree(table->header); table->header = NULL; } return ret; } static inline struct acpi_table_header *get_header(struct config_item *cfg) { struct acpi_table *table = container_of(cfg, struct acpi_table, cfg); if (!table->header) pr_err("table not loaded\n"); return table->header; } static ssize_t acpi_table_aml_read(struct config_item *cfg, void *data, size_t size) { struct acpi_table_header *h = get_header(cfg); if (!h) return -EINVAL; if (data) memcpy(data, h, h->length); return h->length; } #define MAX_ACPI_TABLE_SIZE (128 * 1024) CONFIGFS_BIN_ATTR(acpi_table_, aml, NULL, MAX_ACPI_TABLE_SIZE); static struct configfs_bin_attribute *acpi_table_bin_attrs[] = { &acpi_table_attr_aml, NULL, }; static ssize_t acpi_table_signature_show(struct config_item *cfg, char *str) { struct acpi_table_header *h = get_header(cfg); if (!h) return -EINVAL; return sprintf(str, "%.*s\n", ACPI_NAMESEG_SIZE, h->signature); } static ssize_t acpi_table_length_show(struct config_item *cfg, char *str) { struct acpi_table_header *h = get_header(cfg); if (!h) return -EINVAL; return sprintf(str, "%d\n", h->length); } static ssize_t acpi_table_revision_show(struct config_item *cfg, char *str) { struct acpi_table_header *h = get_header(cfg); if (!h) return -EINVAL; return sprintf(str, "%d\n", h->revision); } static ssize_t acpi_table_oem_id_show(struct config_item *cfg, char *str) { struct acpi_table_header *h = get_header(cfg); if (!h) return -EINVAL; return sprintf(str, "%.*s\n", ACPI_OEM_ID_SIZE, h->oem_id); } static ssize_t acpi_table_oem_table_id_show(struct config_item *cfg, char *str) { struct acpi_table_header *h = get_header(cfg); if (!h) return -EINVAL; return sprintf(str, "%.*s\n", ACPI_OEM_TABLE_ID_SIZE, h->oem_table_id); } static ssize_t acpi_table_oem_revision_show(struct config_item *cfg, char *str) { struct acpi_table_header *h = get_header(cfg); if (!h) return -EINVAL; return sprintf(str, "%d\n", h->oem_revision); } static ssize_t acpi_table_asl_compiler_id_show(struct config_item *cfg, char *str) { struct acpi_table_header *h = get_header(cfg); if (!h) return -EINVAL; return sprintf(str, "%.*s\n", ACPI_NAMESEG_SIZE, h->asl_compiler_id); } static ssize_t acpi_table_asl_compiler_revision_show(struct config_item *cfg, char *str) { struct acpi_table_header *h = get_header(cfg); if (!h) return -EINVAL; return sprintf(str, "%d\n", h->asl_compiler_revision); } CONFIGFS_ATTR_RO(acpi_table_, signature); CONFIGFS_ATTR_RO(acpi_table_, length); CONFIGFS_ATTR_RO(acpi_table_, revision); CONFIGFS_ATTR_RO(acpi_table_, oem_id); CONFIGFS_ATTR_RO(acpi_table_, oem_table_id); CONFIGFS_ATTR_RO(acpi_table_, oem_revision); CONFIGFS_ATTR_RO(acpi_table_, asl_compiler_id); CONFIGFS_ATTR_RO(acpi_table_, asl_compiler_revision); static struct configfs_attribute *acpi_table_attrs[] = { &acpi_table_attr_signature, &acpi_table_attr_length, &acpi_table_attr_revision, &acpi_table_attr_oem_id, &acpi_table_attr_oem_table_id, &acpi_table_attr_oem_revision, &acpi_table_attr_asl_compiler_id, &acpi_table_attr_asl_compiler_revision, NULL, }; static const struct config_item_type acpi_table_type = { .ct_owner = THIS_MODULE, .ct_bin_attrs = acpi_table_bin_attrs, .ct_attrs = acpi_table_attrs, }; static struct config_item *acpi_table_make_item(struct config_group *group, const char *name) { struct acpi_table *table; table = kzalloc(sizeof(*table), GFP_KERNEL); if (!table) return ERR_PTR(-ENOMEM); config_item_init_type_name(&table->cfg, name, &acpi_table_type); return &table->cfg; } static void acpi_table_drop_item(struct config_group *group, struct config_item *cfg) { struct acpi_table *table = container_of(cfg, struct acpi_table, cfg); ACPI_INFO(("Host-directed Dynamic ACPI Table Unload")); acpi_unload_table(table->index); } static struct configfs_group_operations acpi_table_group_ops = { .make_item = acpi_table_make_item, .drop_item = acpi_table_drop_item, }; static const struct config_item_type acpi_tables_type = { .ct_owner = THIS_MODULE, .ct_group_ops = &acpi_table_group_ops, }; static const struct config_item_type acpi_root_group_type = { .ct_owner = THIS_MODULE, }; static struct configfs_subsystem acpi_configfs = { .su_group = { .cg_item = { .ci_namebuf = "acpi", .ci_type = &acpi_root_group_type, }, }, .su_mutex = __MUTEX_INITIALIZER(acpi_configfs.su_mutex), }; static int __init acpi_configfs_init(void) { int ret; struct config_group *root = &acpi_configfs.su_group; config_group_init(root); ret = configfs_register_subsystem(&acpi_configfs); if (ret) return ret; acpi_table_group = configfs_register_default_group(root, "table", &acpi_tables_type); return PTR_ERR_OR_ZERO(acpi_table_group); } module_init(acpi_configfs_init); static void __exit acpi_configfs_exit(void) { configfs_unregister_default_group(acpi_table_group); configfs_unregister_subsystem(&acpi_configfs); } module_exit(acpi_configfs_exit); MODULE_AUTHOR("Octavian Purdila "); MODULE_DESCRIPTION("ACPI configfs support"); MODULE_LICENSE("GPL v2");