diff options
Diffstat (limited to 'drivers/firmware/efivars.c')
-rw-r--r-- | drivers/firmware/efivars.c | 343 |
1 files changed, 205 insertions, 138 deletions
diff --git a/drivers/firmware/efivars.c b/drivers/firmware/efivars.c index 2a62ec6390e0..ff0c373e3bbf 100644 --- a/drivers/firmware/efivars.c +++ b/drivers/firmware/efivars.c @@ -90,17 +90,6 @@ MODULE_LICENSE("GPL"); MODULE_VERSION(EFIVARS_VERSION); /* - * efivars_lock protects two things: - * 1) efivar_list - adds, removals, reads, writes - * 2) efi.[gs]et_variable() calls. - * It must not be held when creating sysfs entries or calling kmalloc. - * efi.get_next_variable() is only called from efivars_init(), - * which is protected by the BKL, so that path is safe. - */ -static DEFINE_SPINLOCK(efivars_lock); -static LIST_HEAD(efivar_list); - -/* * The maximum size of VariableName + Data = 1024 * Therefore, it's reasonable to save that much * space in each part of the structure, @@ -118,6 +107,7 @@ struct efi_variable { struct efivar_entry { + struct efivars *efivars; struct efi_variable var; struct list_head list; struct kobject kobj; @@ -144,9 +134,10 @@ struct efivar_attribute efivar_attr_##_name = { \ * Prototype for sysfs creation function */ static int -efivar_create_sysfs_entry(unsigned long variable_name_size, - efi_char16_t *variable_name, - efi_guid_t *vendor_guid); +efivar_create_sysfs_entry(struct efivars *efivars, + unsigned long variable_name_size, + efi_char16_t *variable_name, + efi_guid_t *vendor_guid); /* Return the number of unicode characters in data */ static unsigned long @@ -170,18 +161,18 @@ utf8_strsize(efi_char16_t *data, unsigned long maxlength) } static efi_status_t -get_var_data(struct efi_variable *var) +get_var_data(struct efivars *efivars, struct efi_variable *var) { efi_status_t status; - spin_lock(&efivars_lock); + spin_lock(&efivars->lock); var->DataSize = 1024; - status = efi.get_variable(var->VariableName, - &var->VendorGuid, - &var->Attributes, - &var->DataSize, - var->Data); - spin_unlock(&efivars_lock); + status = efivars->ops->get_variable(var->VariableName, + &var->VendorGuid, + &var->Attributes, + &var->DataSize, + var->Data); + spin_unlock(&efivars->lock); if (status != EFI_SUCCESS) { printk(KERN_WARNING "efivars: get_variable() failed 0x%lx!\n", status); @@ -215,7 +206,7 @@ efivar_attr_read(struct efivar_entry *entry, char *buf) if (!entry || !buf) return -EINVAL; - status = get_var_data(var); + status = get_var_data(entry->efivars, var); if (status != EFI_SUCCESS) return -EIO; @@ -238,7 +229,7 @@ efivar_size_read(struct efivar_entry *entry, char *buf) if (!entry || !buf) return -EINVAL; - status = get_var_data(var); + status = get_var_data(entry->efivars, var); if (status != EFI_SUCCESS) return -EIO; @@ -255,7 +246,7 @@ efivar_data_read(struct efivar_entry *entry, char *buf) if (!entry || !buf) return -EINVAL; - status = get_var_data(var); + status = get_var_data(entry->efivars, var); if (status != EFI_SUCCESS) return -EIO; @@ -270,6 +261,7 @@ static ssize_t efivar_store_raw(struct efivar_entry *entry, const char *buf, size_t count) { struct efi_variable *new_var, *var = &entry->var; + struct efivars *efivars = entry->efivars; efi_status_t status = EFI_NOT_FOUND; if (count != sizeof(struct efi_variable)) @@ -291,14 +283,14 @@ efivar_store_raw(struct efivar_entry *entry, const char *buf, size_t count) return -EINVAL; } - spin_lock(&efivars_lock); - status = efi.set_variable(new_var->VariableName, - &new_var->VendorGuid, - new_var->Attributes, - new_var->DataSize, - new_var->Data); + spin_lock(&efivars->lock); + status = efivars->ops->set_variable(new_var->VariableName, + &new_var->VendorGuid, + new_var->Attributes, + new_var->DataSize, + new_var->Data); - spin_unlock(&efivars_lock); + spin_unlock(&efivars->lock); if (status != EFI_SUCCESS) { printk(KERN_WARNING "efivars: set_variable() failed: status=%lx\n", @@ -319,7 +311,7 @@ efivar_show_raw(struct efivar_entry *entry, char *buf) if (!entry || !buf) return 0; - status = get_var_data(var); + status = get_var_data(entry->efivars, var); if (status != EFI_SUCCESS) return -EIO; @@ -407,6 +399,7 @@ static ssize_t efivar_create(struct file *filp, struct kobject *kobj, char *buf, loff_t pos, size_t count) { struct efi_variable *new_var = (struct efi_variable *)buf; + struct efivars *efivars = bin_attr->private; struct efivar_entry *search_efivar, *n; unsigned long strsize1, strsize2; efi_status_t status = EFI_NOT_FOUND; @@ -415,12 +408,12 @@ static ssize_t efivar_create(struct file *filp, struct kobject *kobj, if (!capable(CAP_SYS_ADMIN)) return -EACCES; - spin_lock(&efivars_lock); + spin_lock(&efivars->lock); /* * Does this variable already exist? */ - list_for_each_entry_safe(search_efivar, n, &efivar_list, list) { + list_for_each_entry_safe(search_efivar, n, &efivars->list, list) { strsize1 = utf8_strsize(search_efivar->var.VariableName, 1024); strsize2 = utf8_strsize(new_var->VariableName, 1024); if (strsize1 == strsize2 && @@ -433,28 +426,31 @@ static ssize_t efivar_create(struct file *filp, struct kobject *kobj, } } if (found) { - spin_unlock(&efivars_lock); + spin_unlock(&efivars->lock); return -EINVAL; } /* now *really* create the variable via EFI */ - status = efi.set_variable(new_var->VariableName, - &new_var->VendorGuid, - new_var->Attributes, - new_var->DataSize, - new_var->Data); + status = efivars->ops->set_variable(new_var->VariableName, + &new_var->VendorGuid, + new_var->Attributes, + new_var->DataSize, + new_var->Data); if (status != EFI_SUCCESS) { printk(KERN_WARNING "efivars: set_variable() failed: status=%lx\n", status); - spin_unlock(&efivars_lock); + spin_unlock(&efivars->lock); return -EIO; } - spin_unlock(&efivars_lock); + spin_unlock(&efivars->lock); /* Create the entry in sysfs. Locking is not required here */ - status = efivar_create_sysfs_entry(utf8_strsize(new_var->VariableName, - 1024), new_var->VariableName, &new_var->VendorGuid); + status = efivar_create_sysfs_entry(efivars, + utf8_strsize(new_var->VariableName, + 1024), + new_var->VariableName, + &new_var->VendorGuid); if (status) { printk(KERN_WARNING "efivars: variable created, but sysfs entry wasn't.\n"); } @@ -466,6 +462,7 @@ static ssize_t efivar_delete(struct file *filp, struct kobject *kobj, char *buf, loff_t pos, size_t count) { struct efi_variable *del_var = (struct efi_variable *)buf; + struct efivars *efivars = bin_attr->private; struct efivar_entry *search_efivar, *n; unsigned long strsize1, strsize2; efi_status_t status = EFI_NOT_FOUND; @@ -474,12 +471,12 @@ static ssize_t efivar_delete(struct file *filp, struct kobject *kobj, if (!capable(CAP_SYS_ADMIN)) return -EACCES; - spin_lock(&efivars_lock); + spin_lock(&efivars->lock); /* * Does this variable already exist? */ - list_for_each_entry_safe(search_efivar, n, &efivar_list, list) { + list_for_each_entry_safe(search_efivar, n, &efivars->list, list) { strsize1 = utf8_strsize(search_efivar->var.VariableName, 1024); strsize2 = utf8_strsize(del_var->VariableName, 1024); if (strsize1 == strsize2 && @@ -492,44 +489,34 @@ static ssize_t efivar_delete(struct file *filp, struct kobject *kobj, } } if (!found) { - spin_unlock(&efivars_lock); + spin_unlock(&efivars->lock); return -EINVAL; } /* force the Attributes/DataSize to 0 to ensure deletion */ del_var->Attributes = 0; del_var->DataSize = 0; - status = efi.set_variable(del_var->VariableName, - &del_var->VendorGuid, - del_var->Attributes, - del_var->DataSize, - del_var->Data); + status = efivars->ops->set_variable(del_var->VariableName, + &del_var->VendorGuid, + del_var->Attributes, + del_var->DataSize, + del_var->Data); if (status != EFI_SUCCESS) { printk(KERN_WARNING "efivars: set_variable() failed: status=%lx\n", status); - spin_unlock(&efivars_lock); + spin_unlock(&efivars->lock); return -EIO; } list_del(&search_efivar->list); /* We need to release this lock before unregistering. */ - spin_unlock(&efivars_lock); + spin_unlock(&efivars->lock); efivar_unregister(search_efivar); /* It's dead Jim.... */ return count; } -static struct bin_attribute var_subsys_attr_new_var = { - .attr = {.name = "new_var", .mode = 0200}, - .write = efivar_create, -}; - -static struct bin_attribute var_subsys_attr_del_var = { - .attr = {.name = "del_var", .mode = 0200}, - .write = efivar_delete, -}; - /* * Let's not leave out systab information that snuck into * the efivars driver @@ -572,8 +559,6 @@ static struct attribute_group efi_subsys_attr_group = { .attrs = efi_subsys_attrs, }; - -static struct kset *vars_kset; static struct kobject *efi_kobj; /* @@ -582,13 +567,14 @@ static struct kobject *efi_kobj; * variable_name_size = number of bytes required to hold * variable_name (not counting the NULL * character at the end. - * efivars_lock is not held on entry or exit. + * efivars->lock is not held on entry or exit. * Returns 1 on failure, 0 on success */ static int -efivar_create_sysfs_entry(unsigned long variable_name_size, - efi_char16_t *variable_name, - efi_guid_t *vendor_guid) +efivar_create_sysfs_entry(struct efivars *efivars, + unsigned long variable_name_size, + efi_char16_t *variable_name, + efi_guid_t *vendor_guid) { int i, short_name_size = variable_name_size / sizeof(efi_char16_t) + 38; char *short_name; @@ -603,6 +589,7 @@ efivar_create_sysfs_entry(unsigned long variable_name_size, return 1; } + new_efivar->efivars = efivars; memcpy(new_efivar->var.VariableName, variable_name, variable_name_size); memcpy(&(new_efivar->var.VendorGuid), vendor_guid, sizeof(efi_guid_t)); @@ -618,7 +605,7 @@ efivar_create_sysfs_entry(unsigned long variable_name_size, *(short_name + strlen(short_name)) = '-'; efi_guid_unparse(vendor_guid, short_name + strlen(short_name)); - new_efivar->kobj.kset = vars_kset; + new_efivar->kobj.kset = efivars->kset; i = kobject_init_and_add(&new_efivar->kobj, &efivar_ktype, NULL, "%s", short_name); if (i) { @@ -631,22 +618,95 @@ efivar_create_sysfs_entry(unsigned long variable_name_size, kfree(short_name); short_name = NULL; - spin_lock(&efivars_lock); - list_add(&new_efivar->list, &efivar_list); - spin_unlock(&efivars_lock); + spin_lock(&efivars->lock); + list_add(&new_efivar->list, &efivars->list); + spin_unlock(&efivars->lock); return 0; } -/* - * For now we register the efi subsystem with the firmware subsystem - * and the vars subsystem with the efi subsystem. In the future, it - * might make sense to split off the efi subsystem into its own - * driver, but for now only efivars will register with it, so just - * include it here. - */ -static int __init -efivars_init(void) +static int +create_efivars_bin_attributes(struct efivars *efivars) +{ + struct bin_attribute *attr; + int error; + + /* new_var */ + attr = kzalloc(sizeof(*attr), GFP_KERNEL); + if (!attr) + return -ENOMEM; + + attr->attr.name = "new_var"; + attr->attr.mode = 0200; + attr->write = efivar_create; + attr->private = efivars; + efivars->new_var = attr; + + /* del_var */ + attr = kzalloc(sizeof(*attr), GFP_KERNEL); + if (!attr) { + error = -ENOMEM; + goto out_free; + } + attr->attr.name = "del_var"; + attr->attr.mode = 0200; + attr->write = efivar_delete; + attr->private = efivars; + efivars->del_var = attr; + + sysfs_bin_attr_init(efivars->new_var); + sysfs_bin_attr_init(efivars->del_var); + + /* Register */ + error = sysfs_create_bin_file(&efivars->kset->kobj, + efivars->new_var); + if (error) { + printk(KERN_ERR "efivars: unable to create new_var sysfs file" + " due to error %d\n", error); + goto out_free; + } + error = sysfs_create_bin_file(&efivars->kset->kobj, + efivars->del_var); + if (error) { + printk(KERN_ERR "efivars: unable to create del_var sysfs file" + " due to error %d\n", error); + sysfs_remove_bin_file(&efivars->kset->kobj, + efivars->new_var); + goto out_free; + } + + return 0; +out_free: + kfree(efivars->new_var); + efivars->new_var = NULL; + kfree(efivars->new_var); + efivars->new_var = NULL; + return error; +} + +void unregister_efivars(struct efivars *efivars) +{ + struct efivar_entry *entry, *n; + + list_for_each_entry_safe(entry, n, &efivars->list, list) { + spin_lock(&efivars->lock); + list_del(&entry->list); + spin_unlock(&efivars->lock); + efivar_unregister(entry); + } + if (efivars->new_var) + sysfs_remove_bin_file(&efivars->kset->kobj, efivars->new_var); + if (efivars->del_var) + sysfs_remove_bin_file(&efivars->kset->kobj, efivars->del_var); + kfree(efivars->new_var); + kfree(efivars->del_var); + kset_unregister(efivars->kset); +} +EXPORT_SYMBOL_GPL(unregister_efivars); + +int register_efivars(struct efivars *efivars, + const struct efivar_operations *ops, + struct kobject *parent_kobj) { efi_status_t status = EFI_NOT_FOUND; efi_guid_t vendor_guid; @@ -654,31 +714,21 @@ efivars_init(void) unsigned long variable_name_size = 1024; int error = 0; - if (!efi_enabled) - return -ENODEV; - variable_name = kzalloc(variable_name_size, GFP_KERNEL); if (!variable_name) { printk(KERN_ERR "efivars: Memory allocation failed.\n"); return -ENOMEM; } - printk(KERN_INFO "EFI Variables Facility v%s %s\n", EFIVARS_VERSION, - EFIVARS_DATE); + spin_lock_init(&efivars->lock); + INIT_LIST_HEAD(&efivars->list); + efivars->ops = ops; - /* For now we'll register the efi directory at /sys/firmware/efi */ - efi_kobj = kobject_create_and_add("efi", firmware_kobj); - if (!efi_kobj) { - printk(KERN_ERR "efivars: Firmware registration failed.\n"); - error = -ENOMEM; - goto out_free; - } - - vars_kset = kset_create_and_add("vars", NULL, efi_kobj); - if (!vars_kset) { + efivars->kset = kset_create_and_add("vars", NULL, parent_kobj); + if (!efivars->kset) { printk(KERN_ERR "efivars: Subsystem registration failed.\n"); error = -ENOMEM; - goto out_firmware_unregister; + goto out; } /* @@ -689,14 +739,15 @@ efivars_init(void) do { variable_name_size = 1024; - status = efi.get_next_variable(&variable_name_size, + status = ops->get_next_variable(&variable_name_size, variable_name, &vendor_guid); switch (status) { case EFI_SUCCESS: - efivar_create_sysfs_entry(variable_name_size, - variable_name, - &vendor_guid); + efivar_create_sysfs_entry(efivars, + variable_name_size, + variable_name, + &vendor_guid); break; case EFI_NOT_FOUND: break; @@ -708,35 +759,60 @@ efivars_init(void) } } while (status != EFI_NOT_FOUND); - /* - * Now add attributes to allow creation of new vars - * and deletion of existing ones... - */ - error = sysfs_create_bin_file(&vars_kset->kobj, - &var_subsys_attr_new_var); - if (error) - printk(KERN_ERR "efivars: unable to create new_var sysfs file" - " due to error %d\n", error); - error = sysfs_create_bin_file(&vars_kset->kobj, - &var_subsys_attr_del_var); + error = create_efivars_bin_attributes(efivars); if (error) - printk(KERN_ERR "efivars: unable to create del_var sysfs file" - " due to error %d\n", error); + unregister_efivars(efivars); - /* Don't forget the systab entry */ - error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group); - if (error) - printk(KERN_ERR "efivars: Sysfs attribute export failed with error %d.\n", error); - else - goto out_free; +out: + kfree(variable_name); - kset_unregister(vars_kset); + return error; +} +EXPORT_SYMBOL_GPL(register_efivars); -out_firmware_unregister: - kobject_put(efi_kobj); +static struct efivars __efivars; +static struct efivar_operations ops; -out_free: - kfree(variable_name); +/* + * For now we register the efi subsystem with the firmware subsystem + * and the vars subsystem with the efi subsystem. In the future, it + * might make sense to split off the efi subsystem into its own + * driver, but for now only efivars will register with it, so just + * include it here. + */ + +static int __init +efivars_init(void) +{ + int error = 0; + + printk(KERN_INFO "EFI Variables Facility v%s %s\n", EFIVARS_VERSION, + EFIVARS_DATE); + + if (!efi_enabled) + return 0; + + /* For now we'll register the efi directory at /sys/firmware/efi */ + efi_kobj = kobject_create_and_add("efi", firmware_kobj); + if (!efi_kobj) { + printk(KERN_ERR "efivars: Firmware registration failed.\n"); + return -ENOMEM; + } + + ops.get_variable = efi.get_variable; + ops.set_variable = efi.set_variable; + ops.get_next_variable = efi.get_next_variable; + error = register_efivars(&__efivars, &ops, efi_kobj); + + /* Don't forget the systab entry */ + error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group); + if (error) { + printk(KERN_ERR + "efivars: Sysfs attribute export failed with error %d.\n", + error); + unregister_efivars(&__efivars); + kobject_put(efi_kobj); + } return error; } @@ -744,16 +820,7 @@ out_free: static void __exit efivars_exit(void) { - struct efivar_entry *entry, *n; - - list_for_each_entry_safe(entry, n, &efivar_list, list) { - spin_lock(&efivars_lock); - list_del(&entry->list); - spin_unlock(&efivars_lock); - efivar_unregister(entry); - } - - kset_unregister(vars_kset); + unregister_efivars(&__efivars); kobject_put(efi_kobj); } |