160 lines · c
1/* SPDX-License-Identifier: GPL-2.0-or-later */2/*3 * configfs_internal.h - Internal stuff for configfs4 *5 * Based on sysfs:6 * sysfs is Copyright (C) 2001, 2002, 2003 Patrick Mochel7 *8 * configfs Copyright (C) 2005 Oracle. All rights reserved.9 */10 11#ifdef pr_fmt12#undef pr_fmt13#endif14 15#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt16 17#include <linux/slab.h>18#include <linux/list.h>19#include <linux/spinlock.h>20 21struct configfs_fragment {22 atomic_t frag_count;23 struct rw_semaphore frag_sem;24 bool frag_dead;25};26 27void put_fragment(struct configfs_fragment *);28struct configfs_fragment *get_fragment(struct configfs_fragment *);29 30struct configfs_dirent {31 atomic_t s_count;32 int s_dependent_count;33 struct list_head s_sibling;34 struct list_head s_children;35 int s_links;36 void * s_element;37 int s_type;38 umode_t s_mode;39 struct dentry * s_dentry;40 struct iattr * s_iattr;41#ifdef CONFIG_LOCKDEP42 int s_depth;43#endif44 struct configfs_fragment *s_frag;45};46 47#define CONFIGFS_ROOT 0x000148#define CONFIGFS_DIR 0x000249#define CONFIGFS_ITEM_ATTR 0x000450#define CONFIGFS_ITEM_BIN_ATTR 0x000851#define CONFIGFS_ITEM_LINK 0x002052#define CONFIGFS_USET_DIR 0x004053#define CONFIGFS_USET_DEFAULT 0x008054#define CONFIGFS_USET_DROPPING 0x010055#define CONFIGFS_USET_IN_MKDIR 0x020056#define CONFIGFS_USET_CREATING 0x040057#define CONFIGFS_NOT_PINNED (CONFIGFS_ITEM_ATTR | CONFIGFS_ITEM_BIN_ATTR)58 59extern struct mutex configfs_symlink_mutex;60extern spinlock_t configfs_dirent_lock;61 62extern struct kmem_cache *configfs_dir_cachep;63 64extern int configfs_is_root(struct config_item *item);65 66extern struct inode * configfs_new_inode(umode_t mode, struct configfs_dirent *, struct super_block *);67extern struct inode *configfs_create(struct dentry *, umode_t mode);68 69extern int configfs_create_file(struct config_item *, const struct configfs_attribute *);70extern int configfs_create_bin_file(struct config_item *,71 const struct configfs_bin_attribute *);72extern int configfs_make_dirent(struct configfs_dirent *, struct dentry *,73 void *, umode_t, int, struct configfs_fragment *);74extern int configfs_dirent_is_ready(struct configfs_dirent *);75 76extern void configfs_hash_and_remove(struct dentry * dir, const char * name);77 78extern const unsigned char * configfs_get_name(struct configfs_dirent *sd);79extern void configfs_drop_dentry(struct configfs_dirent *sd, struct dentry *parent);80extern int configfs_setattr(struct mnt_idmap *idmap,81 struct dentry *dentry, struct iattr *iattr);82 83extern struct dentry *configfs_pin_fs(void);84extern void configfs_release_fs(void);85 86extern const struct file_operations configfs_dir_operations;87extern const struct file_operations configfs_file_operations;88extern const struct file_operations configfs_bin_file_operations;89extern const struct inode_operations configfs_dir_inode_operations;90extern const struct inode_operations configfs_root_inode_operations;91extern const struct inode_operations configfs_symlink_inode_operations;92extern const struct dentry_operations configfs_dentry_ops;93 94extern int configfs_symlink(struct mnt_idmap *idmap,95 struct inode *dir, struct dentry *dentry,96 const char *symname);97extern int configfs_unlink(struct inode *dir, struct dentry *dentry);98 99int configfs_create_link(struct configfs_dirent *target, struct dentry *parent,100 struct dentry *dentry, char *body);101 102static inline struct config_item * to_item(struct dentry * dentry)103{104 struct configfs_dirent * sd = dentry->d_fsdata;105 return ((struct config_item *) sd->s_element);106}107 108static inline struct configfs_attribute * to_attr(struct dentry * dentry)109{110 struct configfs_dirent * sd = dentry->d_fsdata;111 return ((struct configfs_attribute *) sd->s_element);112}113 114static inline struct configfs_bin_attribute *to_bin_attr(struct dentry *dentry)115{116 struct configfs_attribute *attr = to_attr(dentry);117 118 return container_of(attr, struct configfs_bin_attribute, cb_attr);119}120 121static inline struct config_item *configfs_get_config_item(struct dentry *dentry)122{123 struct config_item * item = NULL;124 125 spin_lock(&dentry->d_lock);126 if (!d_unhashed(dentry)) {127 struct configfs_dirent * sd = dentry->d_fsdata;128 item = config_item_get(sd->s_element);129 }130 spin_unlock(&dentry->d_lock);131 132 return item;133}134 135static inline void release_configfs_dirent(struct configfs_dirent * sd)136{137 if (!(sd->s_type & CONFIGFS_ROOT)) {138 kfree(sd->s_iattr);139 put_fragment(sd->s_frag);140 kmem_cache_free(configfs_dir_cachep, sd);141 }142}143 144static inline struct configfs_dirent * configfs_get(struct configfs_dirent * sd)145{146 if (sd) {147 WARN_ON(!atomic_read(&sd->s_count));148 atomic_inc(&sd->s_count);149 }150 return sd;151}152 153static inline void configfs_put(struct configfs_dirent * sd)154{155 WARN_ON(!atomic_read(&sd->s_count));156 if (atomic_dec_and_test(&sd->s_count))157 release_configfs_dirent(sd);158}159 160