diff options
Diffstat (limited to 'include/linux/configfs.h')
| -rw-r--r-- | include/linux/configfs.h | 251 |
1 files changed, 134 insertions, 117 deletions
diff --git a/include/linux/configfs.h b/include/linux/configfs.h index 34025df61829..ef65c75beeaa 100644 --- a/include/linux/configfs.h +++ b/include/linux/configfs.h @@ -1,23 +1,7 @@ -/* -*- mode: c; c-basic-offset: 8; -*- - * vim: noexpandtab sw=8 ts=8 sts=0: - * +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* * configfs.h - definitions for the device driver filesystem * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public - * License as published by the Free Software Foundation; either - * version 2 of the License, or (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * General Public License for more details. - * - * You should have received a copy of the GNU General Public - * License along with this program; if not, write to the - * Free Software Foundation, Inc., 59 Temple Place - Suite 330, - * Boston, MA 021110-1307, USA. - * * Based on sysfs: * sysfs is Copyright (C) 2001, 2002, 2003 Patrick Mochel * @@ -27,7 +11,7 @@ * * configfs Copyright (C) 2005 Oracle. All rights reserved. * - * Please read Documentation/filesystems/configfs/configfs.txt before using + * Please read Documentation/filesystems/configfs.rst before using * the configfs interface, ESPECIALLY the parts about reference counts and * item destructors. */ @@ -35,14 +19,11 @@ #ifndef _CONFIGFS_H_ #define _CONFIGFS_H_ -#include <linux/kernel.h> -#include <linux/types.h> -#include <linux/list.h> -#include <linux/kref.h> -#include <linux/mutex.h> -#include <linux/err.h> - -#include <linux/atomic.h> +#include <linux/stat.h> /* S_IRUGO */ +#include <linux/types.h> /* ssize_t */ +#include <linux/list.h> /* struct list_head */ +#include <linux/kref.h> /* struct kref */ +#include <linux/mutex.h> /* struct mutex */ #define CONFIGFS_ITEM_NAME_LEN 20 @@ -51,6 +32,7 @@ struct module; struct configfs_item_operations; struct configfs_group_operations; struct configfs_attribute; +struct configfs_bin_attribute; struct configfs_subsystem; struct config_item { @@ -60,30 +42,32 @@ struct config_item { struct list_head ci_entry; struct config_item *ci_parent; struct config_group *ci_group; - struct config_item_type *ci_type; + const struct config_item_type *ci_type; struct dentry *ci_dentry; }; -extern int config_item_set_name(struct config_item *, const char *, ...); +extern __printf(2, 3) +int config_item_set_name(struct config_item *, const char *, ...); static inline char *config_item_name(struct config_item * item) { return item->ci_name; } -extern void config_item_init(struct config_item *); extern void config_item_init_type_name(struct config_item *item, const char *name, - struct config_item_type *type); + const struct config_item_type *type); -extern struct config_item * config_item_get(struct config_item *); +extern struct config_item *config_item_get(struct config_item *); +extern struct config_item *config_item_get_unless_zero(struct config_item *); extern void config_item_put(struct config_item *); struct config_item_type { struct module *ct_owner; - struct configfs_item_operations *ct_item_ops; - struct configfs_group_operations *ct_group_ops; + const struct configfs_item_operations *ct_item_ops; + const struct configfs_group_operations *ct_group_ops; struct configfs_attribute **ct_attrs; + struct configfs_bin_attribute **ct_bin_attrs; }; /** @@ -94,13 +78,14 @@ struct config_group { struct config_item cg_item; struct list_head cg_children; struct configfs_subsystem *cg_subsys; - struct config_group **default_groups; + struct list_head default_groups; + struct list_head group_entry; }; extern void config_group_init(struct config_group *group); extern void config_group_init_type_name(struct config_group *group, const char *name, - struct config_item_type *type); + const struct config_item_type *type); static inline struct config_group *to_config_group(struct config_item *item) { @@ -121,90 +106,95 @@ extern struct config_item *config_group_find_item(struct config_group *, const char *); +static inline void configfs_add_default_group(struct config_group *new_group, + struct config_group *group) +{ + list_add_tail(&new_group->group_entry, &group->default_groups); +} + struct configfs_attribute { const char *ca_name; struct module *ca_owner; umode_t ca_mode; + ssize_t (*show)(struct config_item *, char *); + ssize_t (*store)(struct config_item *, const char *, size_t); }; -/* - * Users often need to create attribute structures for their configurable - * attributes, containing a configfs_attribute member and function pointers - * for the show() and store() operations on that attribute. If they don't - * need anything else on the extended attribute structure, they can use - * this macro to define it The argument _item is the name of the - * config_item structure. - */ -#define CONFIGFS_ATTR_STRUCT(_item) \ -struct _item##_attribute { \ - struct configfs_attribute attr; \ - ssize_t (*show)(struct _item *, char *); \ - ssize_t (*store)(struct _item *, const char *, size_t); \ +#define CONFIGFS_ATTR_PERM(_pfx, _name, _perm) \ +static struct configfs_attribute _pfx##attr_##_name = { \ + .ca_name = __stringify(_name), \ + .ca_mode = _perm, \ + .ca_owner = THIS_MODULE, \ + .show = _pfx##_name##_show, \ + .store = _pfx##_name##_store, \ } -/* - * With the extended attribute structure, users can use this macro - * (similar to sysfs' __ATTR) to make defining attributes easier. - * An example: - * #define MYITEM_ATTR(_name, _mode, _show, _store) \ - * struct myitem_attribute childless_attr_##_name = \ - * __CONFIGFS_ATTR(_name, _mode, _show, _store) - */ -#define __CONFIGFS_ATTR(_name, _mode, _show, _store) \ -{ \ - .attr = { \ - .ca_name = __stringify(_name), \ - .ca_mode = _mode, \ - .ca_owner = THIS_MODULE, \ - }, \ - .show = _show, \ - .store = _store, \ +#define CONFIGFS_ATTR(_pfx, _name) CONFIGFS_ATTR_PERM( \ + _pfx, _name, S_IRUGO | S_IWUSR \ +) + +#define CONFIGFS_ATTR_RO(_pfx, _name) \ +static struct configfs_attribute _pfx##attr_##_name = { \ + .ca_name = __stringify(_name), \ + .ca_mode = S_IRUGO, \ + .ca_owner = THIS_MODULE, \ + .show = _pfx##_name##_show, \ } -/* Here is a readonly version, only requiring a show() operation */ -#define __CONFIGFS_ATTR_RO(_name, _show) \ -{ \ - .attr = { \ - .ca_name = __stringify(_name), \ - .ca_mode = 0444, \ - .ca_owner = THIS_MODULE, \ - }, \ - .show = _show, \ + +#define CONFIGFS_ATTR_WO(_pfx, _name) \ +static struct configfs_attribute _pfx##attr_##_name = { \ + .ca_name = __stringify(_name), \ + .ca_mode = S_IWUSR, \ + .ca_owner = THIS_MODULE, \ + .store = _pfx##_name##_store, \ } -/* - * With these extended attributes, the simple show_attribute() and - * store_attribute() operations need to call the show() and store() of the - * attributes. This is a common pattern, so we provide a macro to define - * them. The argument _item is the name of the config_item structure. - * This macro expects the attributes to be named "struct <name>_attribute" - * and the function to_<name>() to exist; - */ -#define CONFIGFS_ATTR_OPS(_item) \ -static ssize_t _item##_attr_show(struct config_item *item, \ - struct configfs_attribute *attr, \ - char *page) \ -{ \ - struct _item *_item = to_##_item(item); \ - struct _item##_attribute *_item##_attr = \ - container_of(attr, struct _item##_attribute, attr); \ - ssize_t ret = 0; \ - \ - if (_item##_attr->show) \ - ret = _item##_attr->show(_item, page); \ - return ret; \ -} \ -static ssize_t _item##_attr_store(struct config_item *item, \ - struct configfs_attribute *attr, \ - const char *page, size_t count) \ -{ \ - struct _item *_item = to_##_item(item); \ - struct _item##_attribute *_item##_attr = \ - container_of(attr, struct _item##_attribute, attr); \ - ssize_t ret = -EINVAL; \ - \ - if (_item##_attr->store) \ - ret = _item##_attr->store(_item, page, count); \ - return ret; \ +struct file; +struct vm_area_struct; + +struct configfs_bin_attribute { + struct configfs_attribute cb_attr; /* std. attribute */ + void *cb_private; /* for user */ + size_t cb_max_size; /* max core size */ + ssize_t (*read)(struct config_item *, void *, size_t); + ssize_t (*write)(struct config_item *, const void *, size_t); +}; + +#define CONFIGFS_BIN_ATTR(_pfx, _name, _priv, _maxsz) \ +static struct configfs_bin_attribute _pfx##attr_##_name = { \ + .cb_attr = { \ + .ca_name = __stringify(_name), \ + .ca_mode = S_IRUGO | S_IWUSR, \ + .ca_owner = THIS_MODULE, \ + }, \ + .cb_private = _priv, \ + .cb_max_size = _maxsz, \ + .read = _pfx##_name##_read, \ + .write = _pfx##_name##_write, \ +} + +#define CONFIGFS_BIN_ATTR_RO(_pfx, _name, _priv, _maxsz) \ +static struct configfs_bin_attribute _pfx##attr_##_name = { \ + .cb_attr = { \ + .ca_name = __stringify(_name), \ + .ca_mode = S_IRUGO, \ + .ca_owner = THIS_MODULE, \ + }, \ + .cb_private = _priv, \ + .cb_max_size = _maxsz, \ + .read = _pfx##_name##_read, \ +} + +#define CONFIGFS_BIN_ATTR_WO(_pfx, _name, _priv, _maxsz) \ +static struct configfs_bin_attribute _pfx##attr_##_name = { \ + .cb_attr = { \ + .ca_name = __stringify(_name), \ + .ca_mode = S_IWUSR, \ + .ca_owner = THIS_MODULE, \ + }, \ + .cb_private = _priv, \ + .cb_max_size = _maxsz, \ + .write = _pfx##_name##_write, \ } /* @@ -218,23 +208,21 @@ static ssize_t _item##_attr_store(struct config_item *item, \ * group children. default_groups may coexist alongsize make_group() or * make_item(), but if the group wishes to have only default_groups * children (disallowing mkdir(2)), it need not provide either function. - * If the group has commit(), it supports pending and committed (active) - * items. */ struct configfs_item_operations { void (*release)(struct config_item *); - ssize_t (*show_attribute)(struct config_item *, struct configfs_attribute *,char *); - ssize_t (*store_attribute)(struct config_item *,struct configfs_attribute *,const char *, size_t); int (*allow_link)(struct config_item *src, struct config_item *target); - int (*drop_link)(struct config_item *src, struct config_item *target); + void (*drop_link)(struct config_item *src, struct config_item *target); }; struct configfs_group_operations { struct config_item *(*make_item)(struct config_group *group, const char *name); struct config_group *(*make_group)(struct config_group *group, const char *name); - int (*commit_item)(struct config_item *item); void (*disconnect_notify)(struct config_group *group, struct config_item *item); void (*drop_item)(struct config_group *group, struct config_item *item); + bool (*is_visible)(struct config_item *item, struct configfs_attribute *attr, int n); + bool (*is_bin_visible)(struct config_item *item, struct configfs_bin_attribute *attr, + int n); }; struct configfs_subsystem { @@ -252,9 +240,38 @@ static inline struct configfs_subsystem *to_configfs_subsystem(struct config_gro int configfs_register_subsystem(struct configfs_subsystem *subsys); void configfs_unregister_subsystem(struct configfs_subsystem *subsys); +int configfs_register_group(struct config_group *parent_group, + struct config_group *group); +void configfs_unregister_group(struct config_group *group); + +void configfs_remove_default_groups(struct config_group *group); + +struct config_group * +configfs_register_default_group(struct config_group *parent_group, + const char *name, + const struct config_item_type *item_type); +void configfs_unregister_default_group(struct config_group *group); + /* These functions can sleep and can alloc with GFP_KERNEL */ /* WARNING: These cannot be called underneath configfs callbacks!! */ -int configfs_depend_item(struct configfs_subsystem *subsys, struct config_item *target); -void configfs_undepend_item(struct configfs_subsystem *subsys, struct config_item *target); +int configfs_depend_item(struct configfs_subsystem *subsys, + struct config_item *target); +void configfs_undepend_item(struct config_item *target); + +/* + * These functions can sleep and can alloc with GFP_KERNEL + * NOTE: These should be called only underneath configfs callbacks. + * NOTE: First parameter is a caller's subsystem, not target's. + * WARNING: These cannot be called on newly created item + * (in make_group()/make_item() callback) + */ +int configfs_depend_item_unlocked(struct configfs_subsystem *caller_subsys, + struct config_item *target); + + +static inline void configfs_undepend_item_unlocked(struct config_item *target) +{ + configfs_undepend_item(target); +} #endif /* _CONFIGFS_H_ */ |