diff --git a/drivers/firmware/efivars.c b/drivers/firmware/efivars.c index eab4ec41c523..82fd145ead3b 100644 --- a/drivers/firmware/efivars.c +++ b/drivers/firmware/efivars.c @@ -97,39 +97,14 @@ MODULE_VERSION(EFIVARS_VERSION); #define DUMP_NAME_LEN 52 -/* - * Length of a GUID string (strlen("aaaaaaaa-bbbb-cccc-dddd-eeeeeeeeeeee")) - * not including trailing NUL - */ -#define GUID_LEN 36 +static LIST_HEAD(efivarfs_list); +static LIST_HEAD(efivar_sysfs_list); static bool efivars_pstore_disable = IS_ENABLED(CONFIG_EFI_VARS_PSTORE_DEFAULT_DISABLE); module_param_named(pstore_disable, efivars_pstore_disable, bool, 0644); -/* - * The maximum size of VariableName + Data = 1024 - * Therefore, it's reasonable to save that much - * space in each part of the structure, - * and we use a page for reading/writing. - */ - -struct efi_variable { - efi_char16_t VariableName[1024/sizeof(efi_char16_t)]; - efi_guid_t VendorGuid; - unsigned long DataSize; - __u8 Data[1024]; - efi_status_t Status; - __u32 Attributes; -} __attribute__((packed)); - -struct efivar_entry { - struct efi_variable var; - struct list_head list; - struct kobject kobj; -}; - struct efivar_attribute { struct attribute attr; ssize_t (*show) (struct efivar_entry *entry, char *buf); @@ -144,6 +119,11 @@ static struct efivars *__efivars; EFI_VARIABLE_BOOTSERVICE_ACCESS | \ EFI_VARIABLE_RUNTIME_ACCESS) +static struct kset *efivars_kset; + +static struct bin_attribute *efivars_new_var; +static struct bin_attribute *efivars_del_var; + #define EFIVAR_ATTR(_name, _mode, _show, _store) \ struct efivar_attribute efivar_attr_##_name = { \ .attr = {.name = __stringify(_name), .mode = _mode}, \ @@ -158,10 +138,7 @@ struct efivar_attribute efivar_attr_##_name = { \ * Prototype for sysfs creation function */ static int -efivar_create_sysfs_entry(struct efivars *efivars, - unsigned long variable_name_size, - efi_char16_t *variable_name, - efi_guid_t *vendor_guid); +efivar_create_sysfs_entry(struct efivar_entry *new_var); /* * Prototype for workqueue functions updating sysfs entry @@ -346,8 +323,8 @@ static const struct variable_validate variable_validate[] = { { "", NULL }, }; -static bool -validate_var(struct efi_variable *var, u8 *data, unsigned long len) +bool +efivar_validate(struct efi_variable *var, u8 *data, unsigned long len) { int i; u16 *unicode_name = var->VariableName; @@ -382,47 +359,16 @@ validate_var(struct efi_variable *var, u8 *data, unsigned long len) return true; } +EXPORT_SYMBOL_GPL(efivar_validate); static efi_status_t -get_var_data_locked(struct efivars *efivars, struct efi_variable *var) -{ - efi_status_t status; - - var->DataSize = 1024; - status = efivars->ops->get_variable(var->VariableName, - &var->VendorGuid, - &var->Attributes, - &var->DataSize, - var->Data); - return status; -} - -static efi_status_t -get_var_data(struct efivars *efivars, struct efi_variable *var) -{ - efi_status_t status; - unsigned long flags; - - spin_lock_irqsave(&efivars->lock, flags); - status = get_var_data_locked(efivars, var); - spin_unlock_irqrestore(&efivars->lock, flags); - - if (status != EFI_SUCCESS) { - printk(KERN_WARNING "efivars: get_variable() failed 0x%lx!\n", - status); - } - return status; -} - -static efi_status_t -check_var_size_locked(struct efivars *efivars, u32 attributes, - unsigned long size) +check_var_size(u32 attributes, unsigned long size) { u64 storage_size, remaining_size, max_size; efi_status_t status; - const struct efivar_operations *fops = efivars->ops; + const struct efivar_operations *fops = __efivars->ops; - if (!efivars->ops->query_variable_info) + if (!fops->query_variable_info) return EFI_UNSUPPORTED; status = fops->query_variable_info(attributes, &storage_size, @@ -438,20 +384,6 @@ check_var_size_locked(struct efivars *efivars, u32 attributes, return status; } - -static efi_status_t -check_var_size(struct efivars *efivars, u32 attributes, unsigned long size) -{ - efi_status_t status; - unsigned long flags; - - spin_lock_irqsave(&efivars->lock, flags); - status = check_var_size_locked(efivars, attributes, size); - spin_unlock_irqrestore(&efivars->lock, flags); - - return status; -} - static ssize_t efivar_guid_read(struct efivar_entry *entry, char *buf) { @@ -473,13 +405,12 @@ efivar_attr_read(struct efivar_entry *entry, char *buf) { struct efi_variable *var = &entry->var; char *str = buf; - efi_status_t status; if (!entry || !buf) return -EINVAL; - status = get_var_data(__efivars, var); - if (status != EFI_SUCCESS) + var->DataSize = 1024; + if (efivar_entry_get(entry, &var->Attributes, &var->DataSize, var->Data)) return -EIO; if (var->Attributes & EFI_VARIABLE_NON_VOLATILE) @@ -507,13 +438,12 @@ efivar_size_read(struct efivar_entry *entry, char *buf) { struct efi_variable *var = &entry->var; char *str = buf; - efi_status_t status; if (!entry || !buf) return -EINVAL; - status = get_var_data(__efivars, var); - if (status != EFI_SUCCESS) + var->DataSize = 1024; + if (efivar_entry_get(entry, &var->Attributes, &var->DataSize, var->Data)) return -EIO; str += sprintf(str, "0x%lx\n", var->DataSize); @@ -524,13 +454,12 @@ static ssize_t efivar_data_read(struct efivar_entry *entry, char *buf) { struct efi_variable *var = &entry->var; - efi_status_t status; if (!entry || !buf) return -EINVAL; - status = get_var_data(__efivars, var); - if (status != EFI_SUCCESS) + var->DataSize = 1024; + if (efivar_entry_get(entry, &var->Attributes, &var->DataSize, var->Data)) return -EIO; memcpy(buf, var->Data, var->DataSize); @@ -544,8 +473,7 @@ 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 = __efivars; - efi_status_t status = EFI_NOT_FOUND; + int err; if (count != sizeof(struct efi_variable)) return -EINVAL; @@ -567,32 +495,20 @@ efivar_store_raw(struct efivar_entry *entry, const char *buf, size_t count) } if ((new_var->Attributes & ~EFI_VARIABLE_MASK) != 0 || - validate_var(new_var, new_var->Data, new_var->DataSize) == false) { + efivar_validate(new_var, new_var->Data, new_var->DataSize) == false) { printk(KERN_ERR "efivars: Malformed variable content\n"); return -EINVAL; } - spin_lock_irq(&efivars->lock); + memcpy(&entry->var, new_var, count); - status = check_var_size_locked(efivars, new_var->Attributes, - new_var->DataSize + utf16_strsize(new_var->VariableName, 1024)); - - if (status == EFI_SUCCESS || status == EFI_UNSUPPORTED) - status = efivars->ops->set_variable(new_var->VariableName, - &new_var->VendorGuid, - new_var->Attributes, - new_var->DataSize, - new_var->Data); - - spin_unlock_irq(&efivars->lock); - - if (status != EFI_SUCCESS) { - printk(KERN_WARNING "efivars: set_variable() failed: status=%lx\n", - status); + err = efivar_entry_set(entry, new_var->Attributes, + new_var->DataSize, new_var->Data, false); + if (err) { + printk(KERN_WARNING "efivars: set_variable() failed: status=%d\n", err); return -EIO; } - memcpy(&entry->var, new_var, count); return count; } @@ -600,16 +516,17 @@ static ssize_t efivar_show_raw(struct efivar_entry *entry, char *buf) { struct efi_variable *var = &entry->var; - efi_status_t status; if (!entry || !buf) return 0; - status = get_var_data(__efivars, var); - if (status != EFI_SUCCESS) + var->DataSize = 1024; + if (efivar_entry_get(entry, &entry->var.Attributes, + &entry->var.DataSize, entry->var.Data)) return -EIO; memcpy(buf, var, sizeof(*var)); + return sizeof(*var); } @@ -698,6 +615,9 @@ static int efi_status_to_err(efi_status_t status) int err; switch (status) { + case EFI_SUCCESS: + err = 0; + break; case EFI_INVALID_PARAMETER: err = -EINVAL; break; @@ -714,7 +634,7 @@ static int efi_status_to_err(efi_status_t status) err = -EACCES; break; case EFI_NOT_FOUND: - err = -EIO; + err = -ENOENT; break; default: err = -EINVAL; @@ -727,14 +647,12 @@ static ssize_t efivarfs_file_write(struct file *file, const char __user *userbuf, size_t count, loff_t *ppos) { struct efivar_entry *var = file->private_data; - struct efivars *efivars = __efivars; - efi_status_t status; void *data; u32 attributes; struct inode *inode = file->f_mapping->host; unsigned long datasize = count - sizeof(attributes); - unsigned long newdatasize, varsize; ssize_t bytes = 0; + bool set = false; if (count < sizeof(attributes)) return -EINVAL; @@ -745,23 +663,6 @@ static ssize_t efivarfs_file_write(struct file *file, if (attributes & ~(EFI_VARIABLE_MASK)) return -EINVAL; - /* - * Ensure that the user can't allocate arbitrarily large - * amounts of memory. Pick a default size of 64K if - * QueryVariableInfo() isn't supported by the firmware. - */ - - varsize = datasize + utf16_strsize(var->var.VariableName, 1024); - status = check_var_size(efivars, attributes, varsize); - - if (status != EFI_SUCCESS) { - if (status != EFI_UNSUPPORTED) - return efi_status_to_err(status); - - if (datasize > 65536) - return -ENOSPC; - } - data = kmalloc(datasize, GFP_KERNEL); if (!data) return -ENOMEM; @@ -771,76 +672,24 @@ static ssize_t efivarfs_file_write(struct file *file, goto out; } - if (validate_var(&var->var, data, datasize) == false) { - bytes = -EINVAL; + bytes = efivar_entry_set_get_size(var, attributes, &datasize, + data, &set); + if (!set && bytes) goto out; - } - /* - * The lock here protects the get_variable call, the conditional - * set_variable call, and removal of the variable from the efivars - * list (in the case of an authenticated delete). - */ - spin_lock_irq(&efivars->lock); - - /* - * Ensure that the available space hasn't shrunk below the safe level - */ - - status = check_var_size_locked(efivars, attributes, varsize); - - if (status != EFI_SUCCESS && status != EFI_UNSUPPORTED) { - spin_unlock_irq(&efivars->lock); - kfree(data); - - return efi_status_to_err(status); - } - - status = efivars->ops->set_variable(var->var.VariableName, - &var->var.VendorGuid, - attributes, datasize, - data); - - if (status != EFI_SUCCESS) { - spin_unlock_irq(&efivars->lock); - kfree(data); - - return efi_status_to_err(status); - } - - bytes = count; - - /* - * Writing to the variable may have caused a change in size (which - * could either be an append or an overwrite), or the variable to be - * deleted. Perform a GetVariable() so we can tell what actually - * happened. - */ - newdatasize = 0; - status = efivars->ops->get_variable(var->var.VariableName, - &var->var.VendorGuid, - NULL, &newdatasize, - NULL); - - if (status == EFI_BUFFER_TOO_SMALL) { - spin_unlock_irq(&efivars->lock); + if (!bytes) { mutex_lock(&inode->i_mutex); - i_size_write(inode, newdatasize + sizeof(attributes)); + i_size_write(inode, datasize + sizeof(attributes)); mutex_unlock(&inode->i_mutex); - - } else if (status == EFI_NOT_FOUND) { - list_del(&var->list); - spin_unlock_irq(&efivars->lock); - efivar_unregister(var); + } else if (bytes == -ENOENT) { drop_nlink(inode); d_delete(file->f_dentry); dput(file->f_dentry); - - } else { - spin_unlock_irq(&efivars->lock); + } else pr_warn("efivarfs: inconsistent EFI variable implementation? " - "status = %lx\n", status); - } + "status=%zu\n", bytes); + + bytes = count; out: kfree(data); @@ -852,38 +701,25 @@ static ssize_t efivarfs_file_read(struct file *file, char __user *userbuf, size_t count, loff_t *ppos) { struct efivar_entry *var = file->private_data; - struct efivars *efivars = __efivars; - efi_status_t status; unsigned long datasize = 0; u32 attributes; void *data; ssize_t size = 0; + int err; - spin_lock_irq(&efivars->lock); - status = efivars->ops->get_variable(var->var.VariableName, - &var->var.VendorGuid, - &attributes, &datasize, NULL); - spin_unlock_irq(&efivars->lock); - - if (status != EFI_BUFFER_TOO_SMALL) - return efi_status_to_err(status); + err = efivar_entry_size(var, &datasize); + if (err) + return err; data = kmalloc(datasize + sizeof(attributes), GFP_KERNEL); if (!data) return -ENOMEM; - spin_lock_irq(&efivars->lock); - status = efivars->ops->get_variable(var->var.VariableName, - &var->var.VendorGuid, - &attributes, &datasize, - (data + sizeof(attributes))); - spin_unlock_irq(&efivars->lock); - - if (status != EFI_SUCCESS) { - size = efi_status_to_err(status); + size = efivar_entry_get(var, &attributes, &datasize, + data + sizeof(attributes)); + if (size) goto out_free; - } memcpy(data, &attributes, sizeof(attributes)); size = simple_read_from_buffer(userbuf, count, ppos, @@ -947,17 +783,17 @@ static struct inode *efivarfs_get_inode(struct super_block *sb, */ static bool efivarfs_valid_name(const char *str, int len) { - static const char dashes[GUID_LEN] = { + static const char dashes[EFI_VARIABLE_GUID_LEN] = { [8] = 1, [13] = 1, [18] = 1, [23] = 1 }; - const char *s = str + len - GUID_LEN; + const char *s = str + len - EFI_VARIABLE_GUID_LEN; int i; /* * We need a GUID, plus at least one letter for the variable name, * plus the '-' separator */ - if (len < GUID_LEN + 2) + if (len < EFI_VARIABLE_GUID_LEN + 2) return false; /* GUID must be preceded by a '-' */ @@ -969,7 +805,7 @@ static bool efivarfs_valid_name(const char *str, int len) * * 12345678-1234-1234-1234-123456789abc */ - for (i = 0; i < GUID_LEN; i++) { + for (i = 0; i < EFI_VARIABLE_GUID_LEN; i++) { if (dashes[i]) { if (*s++ != '-') return false; @@ -1006,7 +842,6 @@ static int efivarfs_create(struct inode *dir, struct dentry *dentry, umode_t mode, bool excl) { struct inode *inode; - struct efivars *efivars = __efivars; struct efivar_entry *var; int namelen, i = 0, err = 0; @@ -1024,7 +859,7 @@ static int efivarfs_create(struct inode *dir, struct dentry *dentry, } /* length of the variable name itself: remove GUID and separator */ - namelen = dentry->d_name.len - GUID_LEN - 1; + namelen = dentry->d_name.len - EFI_VARIABLE_GUID_LEN - 1; efivarfs_hex_to_guid(dentry->d_name.name + namelen + 1, &var->var.VendorGuid); @@ -1035,17 +870,8 @@ static int efivarfs_create(struct inode *dir, struct dentry *dentry, var->var.VariableName[i] = '\0'; inode->i_private = var; - var->kobj.kset = efivars->kset; - err = kobject_init_and_add(&var->kobj, &efivar_ktype, NULL, "%s", - dentry->d_name.name); - if (err) - goto out; - - kobject_uevent(&var->kobj, KOBJ_ADD); - spin_lock_irq(&efivars->lock); - list_add(&var->list, &efivars->list); - spin_unlock_irq(&efivars->lock); + efivar_entry_add(var, &efivarfs_list); d_instantiate(dentry, inode); dget(dentry); out: @@ -1059,26 +885,13 @@ out: static int efivarfs_unlink(struct inode *dir, struct dentry *dentry) { struct efivar_entry *var = dentry->d_inode->i_private; - struct efivars *efivars = __efivars; - efi_status_t status; - spin_lock_irq(&efivars->lock); + if (efivar_entry_delete(var)) + return -EINVAL; - status = efivars->ops->set_variable(var->var.VariableName, - &var->var.VendorGuid, - 0, 0, NULL); - - if (status == EFI_SUCCESS || status == EFI_NOT_FOUND) { - list_del(&var->list); - spin_unlock_irq(&efivars->lock); - efivar_unregister(var); - drop_nlink(dentry->d_inode); - dput(dentry); - return 0; - } - - spin_unlock_irq(&efivars->lock); - return -EINVAL; + drop_nlink(dentry->d_inode); + dput(dentry); + return 0; }; /* @@ -1097,7 +910,7 @@ static int efivarfs_d_compare(const struct dentry *parent, const struct inode *p unsigned int len, const char *str, const struct qstr *name) { - int guid = len - GUID_LEN; + int guid = len - EFI_VARIABLE_GUID_LEN; if (name->len != len) return 1; @@ -1107,7 +920,7 @@ static int efivarfs_d_compare(const struct dentry *parent, const struct inode *p return 1; /* Case-insensitive compare for the GUID */ - return strncasecmp(name->name + guid, str + guid, GUID_LEN); + return strncasecmp(name->name + guid, str + guid, EFI_VARIABLE_GUID_LEN); } static int efivarfs_d_hash(const struct dentry *dentry, @@ -1120,7 +933,7 @@ static int efivarfs_d_hash(const struct dentry *dentry, if (!efivarfs_valid_name(s, len)) return -EINVAL; - while (len-- > GUID_LEN) + while (len-- > EFI_VARIABLE_GUID_LEN) hash = partial_name_hash(*s++, hash); /* GUID is case-insensitive. */ @@ -1166,14 +979,86 @@ static struct dentry *efivarfs_alloc_dentry(struct dentry *parent, char *name) return ERR_PTR(-ENOMEM); } +static int efivarfs_callback(efi_char16_t *name16, efi_guid_t vendor, + unsigned long name_size, void *data) +{ + struct super_block *sb = (struct super_block *)data; + struct efivar_entry *entry; + struct inode *inode = NULL; + struct dentry *dentry, *root = sb->s_root; + unsigned long size = 0; + char *name; + int len, i; + int err = -ENOMEM; + + entry = kmalloc(sizeof(*entry), GFP_KERNEL); + if (!entry) + return err; + + memcpy(entry->var.VariableName, name16, name_size); + memcpy(&(entry->var.VendorGuid), &vendor, sizeof(efi_guid_t)); + + len = utf16_strlen(entry->var.VariableName); + + /* name, plus '-', plus GUID, plus NUL*/ + name = kmalloc(len + 1 + EFI_VARIABLE_GUID_LEN + 1, GFP_KERNEL); + if (!name) + goto fail; + + for (i = 0; i < len; i++) + name[i] = entry->var.VariableName[i] & 0xFF; + + name[len] = '-'; + + efi_guid_unparse(&entry->var.VendorGuid, name + len + 1); + + name[len + EFI_VARIABLE_GUID_LEN+1] = '\0'; + + inode = efivarfs_get_inode(sb, root->d_inode, S_IFREG | 0644, 0); + if (!inode) + goto fail_name; + + dentry = efivarfs_alloc_dentry(root, name); + if (IS_ERR(dentry)) { + err = PTR_ERR(dentry); + goto fail_inode; + } + + /* copied by the above to local storage in the dentry. */ + kfree(name); + + efivar_entry_size(entry, &size); + efivar_entry_add(entry, &efivarfs_list); + + mutex_lock(&inode->i_mutex); + inode->i_private = entry; + i_size_write(inode, size + sizeof(entry->var.Attributes)); + mutex_unlock(&inode->i_mutex); + d_add(dentry, inode); + + return 0; + +fail_inode: + iput(inode); +fail_name: + kfree(name); +fail: + kfree(entry); + return err; +} + +static int efivarfs_destroy(struct efivar_entry *entry, void *data) +{ + efivar_entry_remove(entry); + kfree(entry); + return 0; +} + static int efivarfs_fill_super(struct super_block *sb, void *data, int silent) { struct inode *inode = NULL; struct dentry *root; - struct efivar_entry *entry, *n; - struct efivars *efivars = __efivars; - char *name; - int err = -ENOMEM; + int err; efivarfs_sb = sb; @@ -1195,65 +1080,13 @@ static int efivarfs_fill_super(struct super_block *sb, void *data, int silent) if (!root) return -ENOMEM; - list_for_each_entry_safe(entry, n, &efivars->list, list) { - struct dentry *dentry, *root = efivarfs_sb->s_root; - unsigned long size = 0; - int len, i; + INIT_LIST_HEAD(&efivarfs_list); - inode = NULL; + err = efivar_init(efivarfs_callback, (void *)sb, false, + true, &efivarfs_list); + if (err) + __efivar_entry_iter(efivarfs_destroy, &efivarfs_list, NULL, NULL); - len = utf16_strlen(entry->var.VariableName); - - /* name, plus '-', plus GUID, plus NUL*/ - name = kmalloc(len + 1 + GUID_LEN + 1, GFP_ATOMIC); - if (!name) - goto fail; - - for (i = 0; i < len; i++) - name[i] = entry->var.VariableName[i] & 0xFF; - - name[len] = '-'; - - efi_guid_unparse(&entry->var.VendorGuid, name + len + 1); - - name[len+GUID_LEN+1] = '\0'; - - inode = efivarfs_get_inode(efivarfs_sb, root->d_inode, - S_IFREG | 0644, 0); - if (!inode) - goto fail_name; - - dentry = efivarfs_alloc_dentry(root, name); - if (IS_ERR(dentry)) { - err = PTR_ERR(dentry); - goto fail_inode; - } - - /* copied by the above to local storage in the dentry. */ - kfree(name); - - spin_lock_irq(&efivars->lock); - efivars->ops->get_variable(entry->var.VariableName, - &entry->var.VendorGuid, - &entry->var.Attributes, - &size, - NULL); - spin_unlock_irq(&efivars->lock); - - mutex_lock(&inode->i_mutex); - inode->i_private = entry; - i_size_write(inode, size + sizeof(entry->var.Attributes)); - mutex_unlock(&inode->i_mutex); - d_add(dentry, inode); - } - - return 0; - -fail_inode: - iput(inode); -fail_name: - kfree(name); -fail: return err; } @@ -1267,6 +1100,9 @@ static void efivarfs_kill_sb(struct super_block *sb) { kill_litter_super(sb); efivarfs_sb = NULL; + + /* Remove all entries and destroy */ + __efivar_entry_iter(efivarfs_destroy, &efivarfs_list, NULL, NULL); } static struct file_system_type efivarfs_type = { @@ -1298,80 +1134,84 @@ static const struct inode_operations efivarfs_dir_inode_operations = { static int efi_pstore_open(struct pstore_info *psi) { - struct efivars *efivars = __efivars; - - spin_lock_irq(&efivars->lock); - efivars->walk_entry = list_first_entry(&efivars->list, - struct efivar_entry, list); + efivar_entry_iter_begin(); + psi->data = NULL; return 0; } static int efi_pstore_close(struct pstore_info *psi) { - struct efivars *efivars = __efivars; - - spin_unlock_irq(&efivars->lock); + efivar_entry_iter_end(); + psi->data = NULL; return 0; } +struct pstore_read_data { + u64 *id; + enum pstore_type_id *type; + int *count; + struct timespec *timespec; + char **buf; +}; + +static int efi_pstore_read_func(struct efivar_entry *entry, void *data) +{ + efi_guid_t vendor = LINUX_EFI_CRASH_GUID; + struct pstore_read_data *cb_data = data; + char name[DUMP_NAME_LEN]; + int i; + int cnt; + unsigned int part; + unsigned long time, size; + + if (efi_guidcmp(entry->var.VendorGuid, vendor)) + return 0; + + for (i = 0; i < DUMP_NAME_LEN; i++) + name[i] = entry->var.VariableName[i]; + + if (sscanf(name, "dump-type%u-%u-%d-%lu", + cb_data->type, &part, &cnt, &time) == 4) { + *cb_data->id = part; + *cb_data->count = cnt; + cb_data->timespec->tv_sec = time; + cb_data->timespec->tv_nsec = 0; + } else if (sscanf(name, "dump-type%u-%u-%lu", + cb_data->type, &part, &time) == 3) { + /* + * Check if an old format, + * which doesn't support holding + * multiple logs, remains. + */ + *cb_data->id = part; + *cb_data->count = 0; + cb_data->timespec->tv_sec = time; + cb_data->timespec->tv_nsec = 0; + } else + return 0; + + __efivar_entry_size(entry, &size); + *cb_data->buf = kmalloc(size, GFP_KERNEL); + if (*cb_data->buf == NULL) + return -ENOMEM; + memcpy(*cb_data->buf, entry->var.Data, size); + return size; +} + static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type, int *count, struct timespec *timespec, char **buf, struct pstore_info *psi) { - efi_guid_t vendor = LINUX_EFI_CRASH_GUID; - struct efivars *efivars = __efivars; - char name[DUMP_NAME_LEN]; - int i; - int cnt; - unsigned int part, size; - unsigned long time; + struct pstore_read_data data; - while (&efivars->walk_entry->list != &efivars->list) { - if (!efi_guidcmp(efivars->walk_entry->var.VendorGuid, - vendor)) { - for (i = 0; i < DUMP_NAME_LEN; i++) { - name[i] = efivars->walk_entry->var.VariableName[i]; - } - if (sscanf(name, "dump-type%u-%u-%d-%lu", - type, &part, &cnt, &time) == 4) { - *id = part; - *count = cnt; - timespec->tv_sec = time; - timespec->tv_nsec = 0; - } else if (sscanf(name, "dump-type%u-%u-%lu", - type, &part, &time) == 3) { - /* - * Check if an old format, - * which doesn't support holding - * multiple logs, remains. - */ - *id = part; - *count = 0; - timespec->tv_sec = time; - timespec->tv_nsec = 0; - } else { - efivars->walk_entry = list_entry( - efivars->walk_entry->list.next, - struct efivar_entry, list); - continue; - } + data.id = id; + data.type = type; + data.count = count; + data.timespec = timespec; + data.buf = buf; - get_var_data_locked(efivars, &efivars->walk_entry->var); - size = efivars->walk_entry->var.DataSize; - *buf = kmalloc(size, GFP_KERNEL); - if (*buf == NULL) - return -ENOMEM; - memcpy(*buf, efivars->walk_entry->var.Data, - size); - efivars->walk_entry = list_entry( - efivars->walk_entry->list.next, - struct efivar_entry, list); - return size; - } - efivars->walk_entry = list_entry(efivars->walk_entry->list.next, - struct efivar_entry, list); - } - return 0; + return __efivar_entry_iter(efi_pstore_read_func, &efivar_sysfs_list, &data, + (struct efivar_entry **)&psi->data); } static int efi_pstore_write(enum pstore_type_id type, @@ -1382,36 +1222,7 @@ static int efi_pstore_write(enum pstore_type_id type, char name[DUMP_NAME_LEN]; efi_char16_t efi_name[DUMP_NAME_LEN]; efi_guid_t vendor = LINUX_EFI_CRASH_GUID; - struct efivars *efivars = __efivars; int i, ret = 0; - efi_status_t status = EFI_NOT_FOUND; - unsigned long flags; - - if (pstore_cannot_block_path(reason)) { - /* - * If the lock is taken by another cpu in non-blocking path, - * this driver returns without entering firmware to avoid - * hanging up. - */ - if (!spin_trylock_irqsave(&efivars->lock, flags)) - return -EBUSY; - } else - spin_lock_irqsave(&efivars->lock, flags); - - /* - * Check if there is a space enough to log. - * size: a size of logging data - * DUMP_NAME_LEN * 2: a maximum size of variable name - */ - - status = check_var_size_locked(efivars, PSTORE_EFI_ATTRIBUTES, - size + DUMP_NAME_LEN * 2); - - if (status) { - spin_unlock_irqrestore(&efivars->lock, flags); - *id = part; - return -ENOSPC; - } sprintf(name, "dump-type%u-%u-%d-%lu", type, part, count, get_seconds()); @@ -1419,10 +1230,9 @@ static int efi_pstore_write(enum pstore_type_id type, for (i = 0; i < DUMP_NAME_LEN; i++) efi_name[i] = name[i]; - efivars->ops->set_variable(efi_name, &vendor, PSTORE_EFI_ATTRIBUTES, - size, psi->buf); - - spin_unlock_irqrestore(&efivars->lock, flags); + ret = efivar_entry_set_safe(efi_name, vendor, PSTORE_EFI_ATTRIBUTES, + !pstore_cannot_block_path(reason), + size, psi->buf); if (reason == KMSG_DUMP_OOPS && efivar_wq_enabled) schedule_work(&efivar_work); @@ -1431,69 +1241,79 @@ static int efi_pstore_write(enum pstore_type_id type, return ret; }; +struct pstore_erase_data { + u64 id; + enum pstore_type_id type; + int count; + struct timespec time; + efi_char16_t *name; +}; + +/* + * Clean up an entry with the same name + */ +static int efi_pstore_erase_func(struct efivar_entry *entry, void *data) +{ + struct pstore_erase_data *ed = data; + efi_guid_t vendor = LINUX_EFI_CRASH_GUID; + efi_char16_t efi_name_old[DUMP_NAME_LEN]; + efi_char16_t *efi_name = ed->name; + unsigned long utf16_len = utf16_strlen(ed->name); + char name_old[DUMP_NAME_LEN]; + int i; + + if (efi_guidcmp(entry->var.VendorGuid, vendor)) + return 0; + + if (utf16_strncmp(entry->var.VariableName, + efi_name, (size_t)utf16_len)) { + /* + * Check if an old format, which doesn't support + * holding multiple logs, remains. + */ + sprintf(name_old, "dump-type%u-%u-%lu", ed->type, + (unsigned int)ed->id, ed->time.tv_sec); + + for (i = 0; i < DUMP_NAME_LEN; i++) + efi_name_old[i] = name_old[i]; + + if (utf16_strncmp(entry->var.VariableName, efi_name_old, + utf16_strlen(efi_name_old))) + return 0; + } + + /* found */ + __efivar_entry_delete(entry); + return 1; +} + static int efi_pstore_erase(enum pstore_type_id type, u64 id, int count, struct timespec time, struct pstore_info *psi) { + struct pstore_erase_data edata; + struct efivar_entry *entry; char name[DUMP_NAME_LEN]; efi_char16_t efi_name[DUMP_NAME_LEN]; - char name_old[DUMP_NAME_LEN]; - efi_char16_t efi_name_old[DUMP_NAME_LEN]; - efi_guid_t vendor = LINUX_EFI_CRASH_GUID; - struct efivars *efivars = __efivars; - struct efivar_entry *entry, *found = NULL; - int i; + int found, i; sprintf(name, "dump-type%u-%u-%d-%lu", type, (unsigned int)id, count, time.tv_sec); - spin_lock_irq(&efivars->lock); - for (i = 0; i < DUMP_NAME_LEN; i++) efi_name[i] = name[i]; - /* - * Clean up an entry with the same name - */ + edata.id = id; + edata.type = type; + edata.count = count; + edata.time = time; + edata.name = efi_name; - list_for_each_entry(entry, &efivars->list, list) { - get_var_data_locked(efivars, &entry->var); - - if (efi_guidcmp(entry->var.VendorGuid, vendor)) - continue; - if (utf16_strncmp(entry->var.VariableName, efi_name, - utf16_strlen(efi_name))) { - /* - * Check if an old format, - * which doesn't support holding - * multiple logs, remains. - */ - sprintf(name_old, "dump-type%u-%u-%lu", type, - (unsigned int)id, time.tv_sec); - - for (i = 0; i < DUMP_NAME_LEN; i++) - efi_name_old[i] = name_old[i]; - - if (utf16_strncmp(entry->var.VariableName, efi_name_old, - utf16_strlen(efi_name_old))) - continue; - } - - /* found */ - found = entry; - efivars->ops->set_variable(entry->var.VariableName, - &entry->var.VendorGuid, - PSTORE_EFI_ATTRIBUTES, - 0, NULL); - break; - } + efivar_entry_iter_begin(); + found = __efivar_entry_iter(efi_pstore_erase_func, &efivar_sysfs_list, &edata, &entry); + efivar_entry_iter_end(); if (found) - list_del(&found->list); - - spin_unlock_irq(&efivars->lock); - - if (found) - efivar_unregister(found); + efivar_unregister(entry); return 0; } @@ -1508,19 +1328,17 @@ static struct pstore_info efi_pstore_info = { .erase = efi_pstore_erase, }; -static void efivar_pstore_register(struct efivars *efivars) +static void efivar_pstore_register(void) { - efivars->efi_pstore_info = efi_pstore_info; - efivars->efi_pstore_info.buf = kmalloc(4096, GFP_KERNEL); - if (efivars->efi_pstore_info.buf) { - efivars->efi_pstore_info.bufsize = 1024; - efivars->efi_pstore_info.data = efivars; - spin_lock_init(&efivars->efi_pstore_info.buf_lock); - pstore_register(&efivars->efi_pstore_info); + efi_pstore_info.buf = kmalloc(4096, GFP_KERNEL); + if (efi_pstore_info.buf) { + efi_pstore_info.bufsize = 1024; + spin_lock_init(&efi_pstore_info.buf_lock); + pstore_register(&efi_pstore_info); } } #else -static void efivar_pstore_register(struct efivars *efivars) +static void efivar_pstore_register(void) { return; } @@ -1531,76 +1349,41 @@ 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 = __efivars; - struct efivar_entry *search_efivar, *n; - unsigned long strsize1, strsize2; - efi_status_t status = EFI_NOT_FOUND; - int found = 0; + struct efivar_entry *new_entry; + int err; if (!capable(CAP_SYS_ADMIN)) return -EACCES; if ((new_var->Attributes & ~EFI_VARIABLE_MASK) != 0 || - validate_var(new_var, new_var->Data, new_var->DataSize) == false) { + efivar_validate(new_var, new_var->Data, new_var->DataSize) == false) { printk(KERN_ERR "efivars: Malformed variable content\n"); return -EINVAL; } - spin_lock_irq(&efivars->lock); + new_entry = kzalloc(sizeof(*new_entry), GFP_KERNEL); + if (!new_entry) + return -ENOMEM; - /* - * Does this variable already exist? - */ - list_for_each_entry_safe(search_efivar, n, &efivars->list, list) { - strsize1 = utf16_strsize(search_efivar->var.VariableName, 1024); - strsize2 = utf16_strsize(new_var->VariableName, 1024); - if (strsize1 == strsize2 && - !memcmp(&(search_efivar->var.VariableName), - new_var->VariableName, strsize1) && - !efi_guidcmp(search_efivar->var.VendorGuid, - new_var->VendorGuid)) { - found = 1; - break; - } - } - if (found) { - spin_unlock_irq(&efivars->lock); - return -EINVAL; + memcpy(&new_entry->var, new_var, sizeof(*new_var)); + + err = efivar_entry_set(new_entry, new_var->Attributes, new_var->DataSize, + new_var->Data, &efivar_sysfs_list); + if (err) { + if (err == -EEXIST) + err = -EINVAL; + goto out; } - status = check_var_size_locked(efivars, new_var->Attributes, - new_var->DataSize + utf16_strsize(new_var->VariableName, 1024)); - - if (status && status != EFI_UNSUPPORTED) { - spin_unlock_irq(&efivars->lock); - return efi_status_to_err(status); - } - - /* now *really* create the variable via EFI */ - 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_irq(&efivars->lock); - return -EIO; - } - spin_unlock_irq(&efivars->lock); - - /* Create the entry in sysfs. Locking is not required here */ - status = efivar_create_sysfs_entry(efivars, - utf16_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"); + if (efivar_create_sysfs_entry(new_entry)) { + printk(KERN_WARNING "efivars: failed to create sysfs entry.\n"); + kfree(new_entry); } return count; + +out: + kfree(new_entry); + return err; } static ssize_t efivar_delete(struct file *filp, struct kobject *kobj, @@ -1608,70 +1391,40 @@ 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 = __efivars; - struct efivar_entry *search_efivar, *n; - unsigned long strsize1, strsize2; - efi_status_t status = EFI_NOT_FOUND; - int found = 0; + struct efivar_entry *entry; + int err = 0; if (!capable(CAP_SYS_ADMIN)) return -EACCES; - spin_lock_irq(&efivars->lock); + efivar_entry_iter_begin(); + entry = efivar_entry_find(del_var->VariableName, del_var->VendorGuid, + &efivar_sysfs_list, true); + if (!entry) + err = -EINVAL; + else if (__efivar_entry_delete(entry)) + err = -EIO; - /* - * Does this variable already exist? - */ - list_for_each_entry_safe(search_efivar, n, &efivars->list, list) { - strsize1 = utf16_strsize(search_efivar->var.VariableName, 1024); - strsize2 = utf16_strsize(del_var->VariableName, 1024); - if (strsize1 == strsize2 && - !memcmp(&(search_efivar->var.VariableName), - del_var->VariableName, strsize1) && - !efi_guidcmp(search_efivar->var.VendorGuid, - del_var->VendorGuid)) { - found = 1; - break; - } - } - if (!found) { - spin_unlock_irq(&efivars->lock); - return -EINVAL; - } - /* force the Attributes/DataSize to 0 to ensure deletion */ - del_var->Attributes = 0; - del_var->DataSize = 0; + efivar_entry_iter_end(); - status = efivars->ops->set_variable(del_var->VariableName, - &del_var->VendorGuid, - del_var->Attributes, - del_var->DataSize, - del_var->Data); + if (err) + return err; - if (status != EFI_SUCCESS) { - printk(KERN_WARNING "efivars: set_variable() failed: status=%lx\n", - status); - spin_unlock_irq(&efivars->lock); - return -EIO; - } - list_del(&search_efivar->list); - /* We need to release this lock before unregistering. */ - spin_unlock_irq(&efivars->lock); - efivar_unregister(search_efivar); + efivar_unregister(entry); /* It's dead Jim.... */ return count; } -static bool variable_is_present(efi_char16_t *variable_name, efi_guid_t *vendor) +static bool variable_is_present(efi_char16_t *variable_name, efi_guid_t *vendor, + struct list_head *head) { struct efivar_entry *entry, *n; - struct efivars *efivars = __efivars; unsigned long strsize1, strsize2; bool found = false; strsize1 = utf16_strsize(variable_name, 1024); - list_for_each_entry_safe(entry, n, &efivars->list, list) { + list_for_each_entry_safe(entry, n, head, list) { strsize2 = utf16_strsize(entry->var.VariableName, 1024); if (strsize1 == strsize2 && !memcmp(variable_name, &(entry->var.VariableName), @@ -1685,6 +1438,20 @@ static bool variable_is_present(efi_char16_t *variable_name, efi_guid_t *vendor) return found; } +static int efivar_update_sysfs_entry(efi_char16_t *name, efi_guid_t vendor, + unsigned long name_size, void *data) +{ + struct efivar_entry *entry = data; + + if (efivar_entry_find(name, vendor, &efivar_sysfs_list, false)) + return 0; + + memcpy(entry->var.VariableName, name, name_size); + memcpy(&(entry->var.VendorGuid), &vendor, sizeof(efi_guid_t)); + + return 1; +} + /* * Returns the size of variable_name, in bytes, including the * terminating NULL character, or variable_name_size if no NULL @@ -1712,52 +1479,26 @@ static unsigned long var_name_strnsize(efi_char16_t *variable_name, static void efivar_update_sysfs_entries(struct work_struct *work) { - struct efivars *efivars = __efivars; - efi_guid_t vendor; - efi_char16_t *variable_name; - unsigned long variable_name_size = 1024; - efi_status_t status = EFI_NOT_FOUND; - bool found; + struct efivar_entry *entry; + int err; + + entry = kzalloc(sizeof(*entry), GFP_KERNEL); + if (!entry) + return; /* Add new sysfs entries */ while (1) { - variable_name = kzalloc(variable_name_size, GFP_KERNEL); - if (!variable_name) { - pr_err("efivars: Memory allocation failed.\n"); - return; - } + memset(entry, 0, sizeof(*entry)); - spin_lock_irq(&efivars->lock); - found = false; - while (1) { - variable_name_size = 1024; - status = efivars->ops->get_next_variable( - &variable_name_size, - variable_name, - &vendor); - if (status != EFI_SUCCESS) { - break; - } else { - if (!variable_is_present(variable_name, - &vendor)) { - found = true; - break; - } - } - } - spin_unlock_irq(&efivars->lock); - - if (!found) { - kfree(variable_name); + err = efivar_init(efivar_update_sysfs_entry, entry, + true, false, &efivar_sysfs_list); + if (!err) break; - } else { - variable_name_size = var_name_strnsize(variable_name, - variable_name_size); - efivar_create_sysfs_entry(efivars, - variable_name_size, - variable_name, &vendor); - } + + efivar_create_sysfs_entry(entry); } + + kfree(entry); } /* @@ -1804,45 +1545,37 @@ static struct attribute_group efi_subsys_attr_group = { static struct kobject *efi_kobj; -/* - * efivar_create_sysfs_entry() - * Requires: - * 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. +/** + * efivar_create_sysfs_entry - create a new entry in sysfs + * @new_var: efivar entry to create + * * Returns 1 on failure, 0 on success */ static int -efivar_create_sysfs_entry(struct efivars *efivars, - unsigned long variable_name_size, - efi_char16_t *variable_name, - efi_guid_t *vendor_guid) +efivar_create_sysfs_entry(struct efivar_entry *new_var) { int i, short_name_size; char *short_name; - struct efivar_entry *new_efivar; + unsigned long variable_name_size; + efi_char16_t *variable_name; + + variable_name = new_var->var.VariableName; + variable_name_size = utf16_strlen(variable_name) * sizeof(efi_char16_t); /* * Length of the variable bytes in ASCII, plus the '-' separator, * plus the GUID, plus trailing NUL */ short_name_size = variable_name_size / sizeof(efi_char16_t) - + 1 + GUID_LEN + 1; + + 1 + EFI_VARIABLE_GUID_LEN + 1; short_name = kzalloc(short_name_size, GFP_KERNEL); - new_efivar = kzalloc(sizeof(struct efivar_entry), GFP_KERNEL); - if (!short_name || !new_efivar) { + if (!short_name) { kfree(short_name); - kfree(new_efivar); return 1; } - memcpy(new_efivar->var.VariableName, variable_name, - variable_name_size); - memcpy(&(new_efivar->var.VendorGuid), vendor_guid, sizeof(efi_guid_t)); - /* Convert Unicode to normal chars (assume top bits are 0), ala UTF-8 */ for (i=0; i < (int)(variable_name_size / sizeof(efi_char16_t)); i++) { @@ -1852,30 +1585,25 @@ efivar_create_sysfs_entry(struct efivars *efivars, private variables from another's. */ *(short_name + strlen(short_name)) = '-'; - efi_guid_unparse(vendor_guid, short_name + strlen(short_name)); + efi_guid_unparse(&new_var->var.VendorGuid, + short_name + strlen(short_name)); - new_efivar->kobj.kset = efivars->kset; - i = kobject_init_and_add(&new_efivar->kobj, &efivar_ktype, NULL, - "%s", short_name); - if (i) { - kfree(short_name); - kfree(new_efivar); - return 1; - } + new_var->kobj.kset = efivars_kset; - kobject_uevent(&new_efivar->kobj, KOBJ_ADD); + i = kobject_init_and_add(&new_var->kobj, &efivar_ktype, + NULL, "%s", short_name); kfree(short_name); - short_name = NULL; + if (i) + return 1; - spin_lock_irq(&efivars->lock); - list_add(&new_efivar->list, &efivars->list); - spin_unlock_irq(&efivars->lock); + kobject_uevent(&new_var->kobj, KOBJ_ADD); + efivar_entry_add(new_var, &efivar_sysfs_list); return 0; } static int -create_efivars_bin_attributes(struct efivars *efivars) +create_efivars_bin_attributes(void) { struct bin_attribute *attr; int error; @@ -1888,8 +1616,7 @@ create_efivars_bin_attributes(struct efivars *efivars) attr->attr.name = "new_var"; attr->attr.mode = 0200; attr->write = efivar_create; - attr->private = efivars; - efivars->new_var = attr; + efivars_new_var = attr; /* del_var */ attr = kzalloc(sizeof(*attr), GFP_KERNEL); @@ -1900,61 +1627,59 @@ create_efivars_bin_attributes(struct efivars *efivars) attr->attr.name = "del_var"; attr->attr.mode = 0200; attr->write = efivar_delete; - attr->private = efivars; - efivars->del_var = attr; + efivars_del_var = attr; - sysfs_bin_attr_init(efivars->new_var); - sysfs_bin_attr_init(efivars->del_var); + 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); + 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); + + 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); + sysfs_remove_bin_file(&efivars_kset->kobj, efivars_new_var); goto out_free; } return 0; out_free: - kfree(efivars->del_var); - efivars->del_var = NULL; - kfree(efivars->new_var); - efivars->new_var = NULL; + kfree(efivars_del_var); + efivars_del_var = NULL; + kfree(efivars_new_var); + efivars_new_var = NULL; return error; } -void unregister_efivars(struct efivars *efivars) +static int efivars_sysfs_callback(efi_char16_t *name, efi_guid_t vendor, + unsigned long name_size, void *data) { - struct efivar_entry *entry, *n; + struct efivar_entry *entry; - __efivars = NULL; + entry = kzalloc(sizeof(*entry), GFP_KERNEL); + if (!entry) + return -ENOMEM; - list_for_each_entry_safe(entry, n, &efivars->list, list) { - spin_lock_irq(&efivars->lock); - list_del(&entry->list); - spin_unlock_irq(&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); - kobject_put(efivars->kobject); - kset_unregister(efivars->kset); + memcpy(entry->var.VariableName, name, name_size); + memcpy(&(entry->var.VendorGuid), &vendor, sizeof(efi_guid_t)); + + efivar_create_sysfs_entry(entry); + + return 0; +} + +static int efivar_sysfs_destroy(struct efivar_entry *entry, void *data) +{ + efivar_entry_remove(entry); + efivar_unregister(entry); + return 0; } -EXPORT_SYMBOL_GPL(unregister_efivars); /* * Print a warning when duplicate EFI variables are encountered and @@ -1985,17 +1710,82 @@ static void dup_variable_bug(efi_char16_t *s16, efi_guid_t *vendor_guid, kfree(s8); } -int register_efivars(struct efivars *efivars, - const struct efivar_operations *ops, - struct kobject *parent_kobj) +static struct kobject *efivars_kobj; + +void efivars_sysfs_exit(void) { - efi_status_t status = EFI_NOT_FOUND; - efi_guid_t vendor_guid; - efi_char16_t *variable_name; - unsigned long variable_name_size = 1024; + /* Remove all entries and destroy */ + __efivar_entry_iter(efivar_sysfs_destroy, &efivar_sysfs_list, NULL, NULL); + + 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); + kobject_put(efivars_kobj); + kset_unregister(efivars_kset); +} + +int efivars_sysfs_init(void) +{ + struct kobject *parent_kobj = efivars_kobject(); int error = 0; - __efivars = efivars; + /* No efivars has been registered yet */ + if (!parent_kobj) + return 0; + + printk(KERN_INFO "EFI Variables Facility v%s %s\n", EFIVARS_VERSION, + EFIVARS_DATE); + + efivars_kset = kset_create_and_add("vars", NULL, parent_kobj); + if (!efivars_kset) { + printk(KERN_ERR "efivars: Subsystem registration failed.\n"); + return -ENOMEM; + } + + efivars_kobj = kobject_create_and_add("efivars", parent_kobj); + if (!efivars_kobj) { + pr_err("efivars: Subsystem registration failed.\n"); + kset_unregister(efivars_kset); + return -ENOMEM; + } + + efivar_init(efivars_sysfs_callback, NULL, false, + true, &efivar_sysfs_list); + + error = create_efivars_bin_attributes(); + if (error) + efivars_sysfs_exit(); + + return error; +} +EXPORT_SYMBOL_GPL(efivars_sysfs_init); + +/** + * efivar_init - build the initial list of EFI variables + * @func: callback function to invoke for every variable + * @data: function-specific data to pass to @func + * @atomic: do we need to execute the @func-loop atomically? + * @duplicates: error if we encounter duplicates on @head? + * @head: initialised head of variable list + * + * Get every EFI variable from the firmware and invoke @func. @func + * should call efivar_entry_add() to build the list of variables. + * + * Returns 0 on success, or a kernel error code on failure. + */ +int efivar_init(int (*func)(efi_char16_t *, efi_guid_t, unsigned long, void *), + void *data, bool atomic, bool duplicates, + struct list_head *head) +{ + const struct efivar_operations *ops = __efivars->ops; + unsigned long variable_name_size = 1024; + efi_char16_t *variable_name; + efi_status_t status; + efi_guid_t vendor_guid; + int err = 0; variable_name = kzalloc(variable_name_size, GFP_KERNEL); if (!variable_name) { @@ -2003,24 +1793,7 @@ int register_efivars(struct efivars *efivars, return -ENOMEM; } - spin_lock_init(&efivars->lock); - INIT_LIST_HEAD(&efivars->list); - efivars->ops = ops; - - 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; - } - - efivars->kobject = kobject_create_and_add("efivars", parent_kobj); - if (!efivars->kobject) { - pr_err("efivars: Subsystem registration failed.\n"); - error = -ENOMEM; - kset_unregister(efivars->kset); - goto out; - } + spin_lock_irq(&__efivars->lock); /* * Per EFI spec, the maximum storage allocated for both @@ -2035,6 +1808,9 @@ int register_efivars(struct efivars *efivars, &vendor_guid); switch (status) { case EFI_SUCCESS: + if (!atomic) + spin_unlock_irq(&__efivars->lock); + variable_name_size = var_name_strnsize(variable_name, variable_name_size); @@ -2046,17 +1822,24 @@ int register_efivars(struct efivars *efivars, * we'll ever see a different variable name, * and may end up looping here forever. */ - if (variable_is_present(variable_name, &vendor_guid)) { + if (duplicates && + variable_is_present(variable_name, &vendor_guid, head)) { dup_variable_bug(variable_name, &vendor_guid, variable_name_size); + if (!atomic) + spin_lock_irq(&__efivars->lock); + status = EFI_NOT_FOUND; break; } - efivar_create_sysfs_entry(efivars, - variable_name_size, - variable_name, - &vendor_guid); + err = func(variable_name, vendor_guid, variable_name_size, data); + if (err) + status = EFI_NOT_FOUND; + + if (!atomic) + spin_lock_irq(&__efivars->lock); + break; case EFI_NOT_FOUND: break; @@ -2066,40 +1849,637 @@ int register_efivars(struct efivars *efivars, status = EFI_NOT_FOUND; break; } + } while (status != EFI_NOT_FOUND); - error = create_efivars_bin_attributes(efivars); - if (error) - unregister_efivars(efivars); + spin_unlock_irq(&__efivars->lock); + + kfree(variable_name); + + return err; +} +EXPORT_SYMBOL_GPL(efivar_init); + +/** + * efivar_entry_add - add entry to variable list + * @entry: entry to add to list + * @head: list head + */ +void efivar_entry_add(struct efivar_entry *entry, struct list_head *head) +{ + spin_lock_irq(&__efivars->lock); + list_add(&entry->list, head); + spin_unlock_irq(&__efivars->lock); +} +EXPORT_SYMBOL_GPL(efivar_entry_add); + +/** + * efivar_entry_remove - remove entry from variable list + * @entry: entry to remove from list + */ +void efivar_entry_remove(struct efivar_entry *entry) +{ + spin_lock_irq(&__efivars->lock); + list_del(&entry->list); + spin_unlock_irq(&__efivars->lock); +} +EXPORT_SYMBOL_GPL(efivar_entry_remove); + +/* + * efivar_entry_list_del_unlock - remove entry from variable list + * @entry: entry to remove + * + * Remove @entry from the variable list and release the list lock. + * + * NOTE: slightly weird locking semantics here - we expect to be + * called with the efivars lock already held, and we release it before + * returning. This is because this function is usually called after + * set_variable() while the lock is still held. + */ +static void efivar_entry_list_del_unlock(struct efivar_entry *entry) +{ + WARN_ON(!spin_is_locked(&__efivars->lock)); + + list_del(&entry->list); + spin_unlock_irq(&__efivars->lock); +} + +/** + * __efivar_entry_delete - delete an EFI variable + * @entry: entry containing EFI variable to delete + * + * Delete the variable from the firmware and remove @entry from the + * variable list. It is the caller's responsibility to free @entry + * once we return. + * + * This function differs from efivar_entry_delete() because it is + * safe to be called from within a efivar_entry_iter_begin() and + * efivar_entry_iter_end() region, unlike efivar_entry_delete(). + * + * Returns 0 on success, or a converted EFI status code if + * set_variable() fails. If set_variable() fails the entry remains + * on the list. + */ +int __efivar_entry_delete(struct efivar_entry *entry) +{ + const struct efivar_operations *ops = __efivars->ops; + efi_status_t status; + + WARN_ON(!spin_is_locked(&__efivars->lock)); + + status = ops->set_variable(entry->var.VariableName, + &entry->var.VendorGuid, + 0, 0, NULL); + if (status) + return efi_status_to_err(status); + + list_del(&entry->list); + + return 0; +} +EXPORT_SYMBOL_GPL(__efivar_entry_delete); + +/** + * efivar_entry_delete - delete variable and remove entry from list + * @entry: entry containing variable to delete + * + * Delete the variable from the firmware and remove @entry from the + * variable list. It is the caller's responsibility to free @entry + * once we return. + * + * Returns 0 on success, or a converted EFI status code if + * set_variable() fails. + */ +int efivar_entry_delete(struct efivar_entry *entry) +{ + const struct efivar_operations *ops = __efivars->ops; + efi_status_t status; + + spin_lock_irq(&__efivars->lock); + status = ops->set_variable(entry->var.VariableName, + &entry->var.VendorGuid, + 0, 0, NULL); + if (!(status == EFI_SUCCESS || status == EFI_NOT_FOUND)) { + spin_unlock_irq(&__efivars->lock); + return efi_status_to_err(status); + } + + efivar_entry_list_del_unlock(entry); + return 0; +} +EXPORT_SYMBOL_GPL(efivar_entry_delete); + +/** + * efivar_entry_set - call set_variable() + * @entry: entry containing the EFI variable to write + * @attributes: variable attributes + * @size: size of @data buffer + * @data: buffer containing variable data + * @head: head of variable list + * + * Calls set_variable() for an EFI variable. If creating a new EFI + * variable, this function is usually followed by efivar_entry_add(). + * + * Before writing the variable, the remaining EFI variable storage + * space is checked to ensure there is enough room available. + * + * If @head is not NULL a lookup is performed to determine whether + * the entry is already on the list. + * + * Returns 0 on success, -EEXIST if a lookup is performed and the entry + * already exists on the list, or a converted EFI status code if + * set_variable() fails. + */ +int efivar_entry_set(struct efivar_entry *entry, u32 attributes, + unsigned long size, void *data, struct list_head *head) +{ + const struct efivar_operations *ops = __efivars->ops; + efi_status_t status; + efi_char16_t *name = entry->var.VariableName; + efi_guid_t vendor = entry->var.VendorGuid; + + spin_lock_irq(&__efivars->lock); + + if (head && efivar_entry_find(name, vendor, head, false)) { + spin_unlock_irq(&__efivars->lock); + return -EEXIST; + } + + status = check_var_size(attributes, size + utf16_strsize(name, 1024)); + if (status == EFI_SUCCESS || status == EFI_UNSUPPORTED) + status = ops->set_variable(name, &vendor, + attributes, size, data); + + spin_unlock_irq(&__efivars->lock); + + return efi_status_to_err(status); +} +EXPORT_SYMBOL_GPL(efivar_entry_set); + +/** + * efivar_entry_set_safe - call set_variable() if enough space in firmware + * @name: buffer containing the variable name + * @vendor: variable vendor guid + * @attributes: variable attributes + * @block: can we block in this context? + * @size: size of @data buffer + * @data: buffer containing variable data + * + * Ensures there is enough free storage in the firmware for this variable, and + * if so, calls set_variable(). If creating a new EFI variable, this function + * is usually followed by efivar_entry_add(). + * + * Returns 0 on success, -ENOSPC if the firmware does not have enough + * space for set_variable() to succeed, or a converted EFI status code + * if set_variable() fails. + */ +int efivar_entry_set_safe(efi_char16_t *name, efi_guid_t vendor, u32 attributes, + bool block, unsigned long size, void *data) +{ + const struct efivar_operations *ops = __efivars->ops; + unsigned long flags; + efi_status_t status; + + if (!ops->query_variable_info) + return -ENOSYS; + + if (!block && !spin_trylock_irqsave(&__efivars->lock, flags)) + return -EBUSY; + else + spin_lock_irqsave(&__efivars->lock, flags); + + status = check_var_size(attributes, size + utf16_strsize(name, 1024)); + if (status != EFI_SUCCESS) { + spin_unlock_irqrestore(&__efivars->lock, flags); + return -ENOSPC; + } + + status = ops->set_variable(name, &vendor, attributes, size, data); + + spin_unlock_irqrestore(&__efivars->lock, flags); + + return efi_status_to_err(status); +} +EXPORT_SYMBOL_GPL(efivar_entry_set_safe); + +/** + * efivar_entry_find - search for an entry + * @name: the EFI variable name + * @guid: the EFI variable vendor's guid + * @head: head of the variable list + * @remove: should we remove the entry from the list? + * + * Search for an entry on the variable list that has the EFI variable + * name @name and vendor guid @guid. If an entry is found on the list + * and @remove is true, the entry is removed from the list. + * + * The caller MUST call efivar_entry_iter_begin() and + * efivar_entry_iter_end() before and after the invocation of this + * function, respectively. + * + * Returns the entry if found on the list, %NULL otherwise. + */ +struct efivar_entry *efivar_entry_find(efi_char16_t *name, efi_guid_t guid, + struct list_head *head, bool remove) +{ + struct efivar_entry *entry, *n; + int strsize1, strsize2; + bool found = false; + + WARN_ON(!spin_is_locked(&__efivars->lock)); + + list_for_each_entry_safe(entry, n, head, list) { + strsize1 = utf16_strsize(name, 1024); + strsize2 = utf16_strsize(entry->var.VariableName, 1024); + if (strsize1 == strsize2 && + !memcmp(name, &(entry->var.VariableName), strsize1) && + !efi_guidcmp(guid, entry->var.VendorGuid)) { + found = true; + break; + } + } + + if (!found) + return NULL; + + if (remove) + list_del(&entry->list); + + return entry; +} +EXPORT_SYMBOL_GPL(efivar_entry_find); + +/** + * __efivar_entry_size - obtain the size of a variable + * @entry: entry for this variable + * @size: location to store the variable's size + * + * The caller MUST call efivar_entry_iter_begin() and + * efivar_entry_iter_end() before and after the invocation of this + * function, respectively. + */ +int __efivar_entry_size(struct efivar_entry *entry, unsigned long *size) +{ + const struct efivar_operations *ops = __efivars->ops; + efi_status_t status; + + WARN_ON(!spin_is_locked(&__efivars->lock)); + + *size = 0; + status = ops->get_variable(entry->var.VariableName, + &entry->var.VendorGuid, NULL, size, NULL); + if (status != EFI_BUFFER_TOO_SMALL) + return efi_status_to_err(status); + + return 0; +} +EXPORT_SYMBOL_GPL(__efivar_entry_size); + +/** + * efivar_entry_size - obtain the size of a variable + * @entry: entry for this variable + * @size: location to store the variable's size + */ +int efivar_entry_size(struct efivar_entry *entry, unsigned long *size) +{ + const struct efivar_operations *ops = __efivars->ops; + efi_status_t status; + + *size = 0; + + spin_lock_irq(&__efivars->lock); + status = ops->get_variable(entry->var.VariableName, + &entry->var.VendorGuid, NULL, size, NULL); + spin_unlock_irq(&__efivars->lock); + + if (status != EFI_BUFFER_TOO_SMALL) + return efi_status_to_err(status); + + return 0; +} +EXPORT_SYMBOL_GPL(efivar_entry_size); + +/** + * efivar_entry_get - call get_variable() + * @entry: read data for this variable + * @attributes: variable attributes + * @size: size of @data buffer + * @data: buffer to store variable data + */ +int efivar_entry_get(struct efivar_entry *entry, u32 *attributes, + unsigned long *size, void *data) +{ + const struct efivar_operations *ops = __efivars->ops; + efi_status_t status; + + spin_lock_irq(&__efivars->lock); + status = ops->get_variable(entry->var.VariableName, + &entry->var.VendorGuid, + attributes, size, data); + spin_unlock_irq(&__efivars->lock); + + return efi_status_to_err(status); +} +EXPORT_SYMBOL_GPL(efivar_entry_get); + +/** + * efivar_entry_set_get_size - call set_variable() and get new size (atomic) + * @entry: entry containing variable to set and get + * @attributes: attributes of variable to be written + * @size: size of data buffer + * @data: buffer containing data to write + * @set: did the set_variable() call succeed? + * + * This is a pretty special (complex) function. See efivarfs_file_write(). + * + * Atomically call set_variable() for @entry and if the call is + * successful, return the new size of the variable from get_variable() + * in @size. The success of set_variable() is indicated by @set. + * + * Returns 0 on success, -EINVAL if the variable data is invalid, + * -ENOSPC if the firmware does not have enough available space, or a + * converted EFI status code if either of set_variable() or + * get_variable() fail. + * + * If the EFI variable does not exist when calling set_variable() + * (EFI_NOT_FOUND), @entry is removed from the variable list. + */ +int efivar_entry_set_get_size(struct efivar_entry *entry, u32 attributes, + unsigned long *size, void *data, bool *set) +{ + const struct efivar_operations *ops = __efivars->ops; + efi_char16_t *name = entry->var.VariableName; + efi_guid_t *vendor = &entry->var.VendorGuid; + efi_status_t status; + int err; + + *set = false; + + if (efivar_validate(&entry->var, data, *size) == false) + return -EINVAL; + + /* + * The lock here protects the get_variable call, the conditional + * set_variable call, and removal of the variable from the efivars + * list (in the case of an authenticated delete). + */ + spin_lock_irq(&__efivars->lock); + + /* + * Ensure that the available space hasn't shrunk below the safe level + */ + status = check_var_size(attributes, *size + utf16_strsize(name, 1024)); + if (status != EFI_SUCCESS) { + if (status != EFI_UNSUPPORTED) { + err = efi_status_to_err(status); + goto out; + } + + if (*size > 65536) { + err = -ENOSPC; + goto out; + } + } + + status = ops->set_variable(name, vendor, attributes, *size, data); + if (status != EFI_SUCCESS) { + err = efi_status_to_err(status); + goto out; + } + + *set = true; + + /* + * Writing to the variable may have caused a change in size (which + * could either be an append or an overwrite), or the variable to be + * deleted. Perform a GetVariable() so we can tell what actually + * happened. + */ + *size = 0; + status = ops->get_variable(entry->var.VariableName, + &entry->var.VendorGuid, + NULL, size, NULL); + + if (status == EFI_NOT_FOUND) + efivar_entry_list_del_unlock(entry); + else + spin_unlock_irq(&__efivars->lock); + + if (status && status != EFI_BUFFER_TOO_SMALL) + return efi_status_to_err(status); + + return 0; + +out: + spin_unlock_irq(&__efivars->lock); + return err; + +} +EXPORT_SYMBOL_GPL(efivar_entry_set_get_size); + +/** + * efivar_entry_iter_begin - begin iterating the variable list + * + * Lock the variable list to prevent entry insertion and removal until + * efivar_entry_iter_end() is called. This function is usually used in + * conjunction with __efivar_entry_iter() or efivar_entry_iter(). + */ +void efivar_entry_iter_begin(void) +{ + spin_lock_irq(&__efivars->lock); +} +EXPORT_SYMBOL_GPL(efivar_entry_iter_begin); + +/** + * efivar_entry_iter_end - finish iterating the variable list + * + * Unlock the variable list and allow modifications to the list again. + */ +void efivar_entry_iter_end(void) +{ + spin_unlock_irq(&__efivars->lock); +} +EXPORT_SYMBOL_GPL(efivar_entry_iter_end); + +/** + * __efivar_entry_iter - iterate over variable list + * @func: callback function + * @head: head of the variable list + * @data: function-specific data to pass to callback + * @prev: entry to begin iterating from + * + * Iterate over the list of EFI variables and call @func with every + * entry on the list. It is safe for @func to remove entries in the + * list via efivar_entry_delete(). + * + * You MUST call efivar_enter_iter_begin() before this function, and + * efivar_entry_iter_end() afterwards. + * + * It is possible to begin iteration from an arbitrary entry within + * the list by passing @prev. @prev is updated on return to point to + * the last entry passed to @func. To begin iterating from the + * beginning of the list @prev must be %NULL. + * + * The restrictions for @func are the same as documented for + * efivar_entry_iter(). + */ +int __efivar_entry_iter(int (*func)(struct efivar_entry *, void *), + struct list_head *head, void *data, + struct efivar_entry **prev) +{ + struct efivar_entry *entry, *n; + int err = 0; + + if (!prev || !*prev) { + list_for_each_entry_safe(entry, n, head, list) { + err = func(entry, data); + if (err) + break; + } + + if (prev) + *prev = entry; + + return err; + } + + + list_for_each_entry_safe_continue((*prev), n, head, list) { + err = func(*prev, data); + if (err) + break; + } + + return err; +} +EXPORT_SYMBOL_GPL(__efivar_entry_iter); + +/** + * efivar_entry_iter - iterate over variable list + * @func: callback function + * @head: head of variable list + * @data: function-specific data to pass to callback + * + * Iterate over the list of EFI variables and call @func with every + * entry on the list. It is safe for @func to remove entries in the + * list via efivar_entry_delete() while iterating. + * + * Some notes for the callback function: + * - a non-zero return value indicates an error and terminates the loop + * - @func is called from atomic context + */ +int efivar_entry_iter(int (*func)(struct efivar_entry *, void *), + struct list_head *head, void *data) +{ + int err = 0; + + efivar_entry_iter_begin(); + err = __efivar_entry_iter(func, head, data, NULL); + efivar_entry_iter_end(); + + return err; +} +EXPORT_SYMBOL_GPL(efivar_entry_iter); + +/** + * efivars_kobject - get the kobject for the registered efivars + * + * If efivars_register() has not been called we return NULL, + * otherwise return the kobject used at registration time. + */ +struct kobject *efivars_kobject(void) +{ + if (!__efivars) + return NULL; + + return __efivars->kobject; +} +EXPORT_SYMBOL_GPL(efivars_kobject); + +/** + * efivars_register - register an efivars + * @efivars: efivars to register + * @ops: efivars operations + * @kobject: @efivars-specific kobject + * + * Only a single efivars can be registered at any time. + */ +int efivars_register(struct efivars *efivars, + const struct efivar_operations *ops, + struct kobject *kobject) +{ + spin_lock_init(&efivars->lock); + efivars->ops = ops; + efivars->kobject = kobject; + + __efivars = efivars; if (!efivars_pstore_disable) - efivar_pstore_register(efivars); + efivar_pstore_register(); register_filesystem(&efivarfs_type); -out: - kfree(variable_name); - - return error; + return 0; } -EXPORT_SYMBOL_GPL(register_efivars); +EXPORT_SYMBOL_GPL(efivars_register); + +/** + * efivars_unregister - unregister an efivars + * @efivars: efivars to unregister + * + * The caller must have already removed every entry from the list, + * failure to do so is an error. + */ +int efivars_unregister(struct efivars *efivars) +{ + int rv; + + if (!__efivars) { + printk(KERN_ERR "efivars not registered\n"); + rv = -EINVAL; + goto out; + } + + if (__efivars != efivars) { + rv = -EINVAL; + goto out; + } + + __efivars = NULL; + + rv = 0; +out: + return rv; +} +EXPORT_SYMBOL_GPL(efivars_unregister); static struct efivars generic_efivars; static struct efivar_operations generic_ops; static int generic_ops_register(void) { + int error; + generic_ops.get_variable = efi.get_variable; generic_ops.set_variable = efi.set_variable; generic_ops.get_next_variable = efi.get_next_variable; generic_ops.query_variable_info = efi.query_variable_info; - return register_efivars(&generic_efivars, &generic_ops, efi_kobj); + error = efivars_register(&generic_efivars, &generic_ops, efi_kobj); + if (error) + return error; + + error = efivars_sysfs_init(); + if (error) + efivars_unregister(&generic_efivars); + + return error; } static void generic_ops_unregister(void) { - unregister_efivars(&generic_efivars); + efivars_sysfs_exit(); + efivars_unregister(&generic_efivars); } /* @@ -2113,15 +2493,12 @@ static void generic_ops_unregister(void) static int __init efivars_init(void) { - int error = 0; - - printk(KERN_INFO "EFI Variables Facility v%s %s\n", EFIVARS_VERSION, - EFIVARS_DATE); + int error; if (!efi_enabled(EFI_RUNTIME_SERVICES)) return 0; - /* For now we'll register the efi directory at /sys/firmware/efi */ + /* 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"); diff --git a/drivers/firmware/google/gsmi.c b/drivers/firmware/google/gsmi.c index c409a7577afc..757b2d92d5b0 100644 --- a/drivers/firmware/google/gsmi.c +++ b/drivers/firmware/google/gsmi.c @@ -882,12 +882,19 @@ static __init int gsmi_init(void) goto out_remove_bin_file; } - ret = register_efivars(&efivars, &efivar_ops, gsmi_kobj); + ret = efivars_register(&efivars, &efivar_ops, gsmi_kobj); if (ret) { printk(KERN_INFO "gsmi: Failed to register efivars\n"); goto out_remove_sysfs_files; } + ret = efivars_sysfs_init(); + if (ret) { + printk(KERN_INFO "gsmi: Failed to create efivars files\n"); + efivars_unregister(&efivars); + goto out_remove_sysfs_files; + } + register_reboot_notifier(&gsmi_reboot_notifier); register_die_notifier(&gsmi_die_notifier); atomic_notifier_chain_register(&panic_notifier_list, @@ -919,7 +926,7 @@ static void __exit gsmi_exit(void) unregister_die_notifier(&gsmi_die_notifier); atomic_notifier_chain_unregister(&panic_notifier_list, &gsmi_panic_notifier); - unregister_efivars(&efivars); + efivars_unregister(&efivars); sysfs_remove_files(gsmi_kobj, gsmi_attrs); sysfs_remove_bin_file(gsmi_kobj, &eventlog_bin_attr); diff --git a/include/linux/efi.h b/include/linux/efi.h index d1d782a6d34c..cd561b301e6a 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -662,6 +662,12 @@ static inline int efi_enabled(int facility) EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS | \ EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS | \ EFI_VARIABLE_APPEND_WRITE) +/* + * Length of a GUID string (strlen("aaaaaaaa-bbbb-cccc-dddd-eeeeeeeeeeee")) + * not including trailing NUL + */ +#define EFI_VARIABLE_GUID_LEN 36 + /* * The type of search to perform when calling boottime->locate_handle */ @@ -762,19 +768,75 @@ struct efivars { * which is protected by the BKL, so that path is safe. */ spinlock_t lock; - struct list_head list; struct kset *kset; struct kobject *kobject; - struct bin_attribute *new_var, *del_var; const struct efivar_operations *ops; - struct efivar_entry *walk_entry; - struct pstore_info efi_pstore_info; }; -int register_efivars(struct efivars *efivars, +/* + * The maximum size of VariableName + Data = 1024 + * Therefore, it's reasonable to save that much + * space in each part of the structure, + * and we use a page for reading/writing. + */ + +struct efi_variable { + efi_char16_t VariableName[1024/sizeof(efi_char16_t)]; + efi_guid_t VendorGuid; + unsigned long DataSize; + __u8 Data[1024]; + efi_status_t Status; + __u32 Attributes; +} __attribute__((packed)); + +struct efivar_entry { + struct efi_variable var; + struct list_head list; + struct kobject kobj; +}; + +int efivars_register(struct efivars *efivars, const struct efivar_operations *ops, - struct kobject *parent_kobj); -void unregister_efivars(struct efivars *efivars); + struct kobject *kobject); +int efivars_unregister(struct efivars *efivars); +struct kobject *efivars_kobject(void); + +int efivar_init(int (*func)(efi_char16_t *, efi_guid_t, unsigned long, void *), + void *data, bool atomic, bool duplicates, + struct list_head *head); + +void efivar_entry_add(struct efivar_entry *entry, struct list_head *head); +void efivar_entry_remove(struct efivar_entry *entry); + +int __efivar_entry_delete(struct efivar_entry *entry); +int efivar_entry_delete(struct efivar_entry *entry); + +int __efivar_entry_size(struct efivar_entry *entry, unsigned long *size); +int efivar_entry_size(struct efivar_entry *entry, unsigned long *size); +int efivar_entry_get(struct efivar_entry *entry, u32 *attributes, + unsigned long *size, void *data); +int efivar_entry_set(struct efivar_entry *entry, u32 attributes, + unsigned long size, void *data, struct list_head *head); +int efivar_entry_set_get_size(struct efivar_entry *entry, u32 attributes, + unsigned long *size, void *data, bool *set); +int efivar_entry_set_safe(efi_char16_t *name, efi_guid_t vendor, u32 attributes, + bool block, unsigned long size, void *data); + +void efivar_entry_iter_begin(void); +void efivar_entry_iter_end(void); + +int __efivar_entry_iter(int (*func)(struct efivar_entry *, void *), + struct list_head *head, void *data, + struct efivar_entry **prev); +int efivar_entry_iter(int (*func)(struct efivar_entry *, void *), + struct list_head *head, void *data); + +struct efivar_entry *efivar_entry_find(efi_char16_t *name, efi_guid_t guid, + struct list_head *head, bool remove); + +bool efivar_validate(struct efi_variable *var, u8 *data, unsigned long len); + +int efivars_sysfs_init(void); #endif /* CONFIG_EFI_VARS */