1 /* -*- mode: c; c-basic-offset:8; -*- 2 * vim: noexpandtab sw=8 ts=8 sts=0: 3 * 4 * configfs_internal.h - Internal stuff for configfs 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public 8 * License as published by the Free Software Foundation; either 9 * version 2 of the License, or (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14 * General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public 17 * License along with this program; if not, write to the 18 * Free Software Foundation, Inc., 59 Temple Place - Suite 330, 19 * Boston, MA 021110-1307, USA. 20 * 21 * Based on sysfs: 22 * sysfs is Copyright (C) 2001, 2002, 2003 Patrick Mochel 23 * 24 * configfs Copyright (C) 2005 Oracle. All rights reserved. 25 */ 26 27 #ifdef pr_fmt 28 #undef pr_fmt 29 #endif 30 31 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 32 33 #include <linux/slab.h> 34 #include <linux/list.h> 35 #include <linux/spinlock.h> 36 37 struct configfs_dirent { 38 atomic_t s_count; 39 int s_dependent_count; 40 struct list_head s_sibling; 41 struct list_head s_children; 42 struct list_head s_links; 43 void * s_element; 44 int s_type; 45 umode_t s_mode; 46 struct dentry * s_dentry; 47 struct iattr * s_iattr; 48 #ifdef CONFIG_LOCKDEP 49 int s_depth; 50 #endif 51 }; 52 53 #define CONFIGFS_ROOT 0x0001 54 #define CONFIGFS_DIR 0x0002 55 #define CONFIGFS_ITEM_ATTR 0x0004 56 #define CONFIGFS_ITEM_LINK 0x0020 57 #define CONFIGFS_USET_DIR 0x0040 58 #define CONFIGFS_USET_DEFAULT 0x0080 59 #define CONFIGFS_USET_DROPPING 0x0100 60 #define CONFIGFS_USET_IN_MKDIR 0x0200 61 #define CONFIGFS_USET_CREATING 0x0400 62 #define CONFIGFS_NOT_PINNED (CONFIGFS_ITEM_ATTR) 63 64 extern struct mutex configfs_symlink_mutex; 65 extern spinlock_t configfs_dirent_lock; 66 67 extern struct kmem_cache *configfs_dir_cachep; 68 69 extern int configfs_is_root(struct config_item *item); 70 71 extern struct inode * configfs_new_inode(umode_t mode, struct configfs_dirent *, struct super_block *); 72 extern int configfs_create(struct dentry *, umode_t mode, void (*init)(struct inode *)); 73 74 extern int configfs_create_file(struct config_item *, const struct configfs_attribute *); 75 extern int configfs_make_dirent(struct configfs_dirent *, 76 struct dentry *, void *, umode_t, int); 77 extern int configfs_dirent_is_ready(struct configfs_dirent *); 78 79 extern void configfs_hash_and_remove(struct dentry * dir, const char * name); 80 81 extern const unsigned char * configfs_get_name(struct configfs_dirent *sd); 82 extern void configfs_drop_dentry(struct configfs_dirent *sd, struct dentry *parent); 83 extern int configfs_setattr(struct dentry *dentry, struct iattr *iattr); 84 85 extern struct dentry *configfs_pin_fs(void); 86 extern void configfs_release_fs(void); 87 88 extern struct rw_semaphore configfs_rename_sem; 89 extern const struct file_operations configfs_dir_operations; 90 extern const struct file_operations configfs_file_operations; 91 extern const struct file_operations bin_fops; 92 extern const struct inode_operations configfs_dir_inode_operations; 93 extern const struct inode_operations configfs_root_inode_operations; 94 extern const struct inode_operations configfs_symlink_inode_operations; 95 extern const struct dentry_operations configfs_dentry_ops; 96 97 extern int configfs_symlink(struct inode *dir, struct dentry *dentry, 98 const char *symname); 99 extern int configfs_unlink(struct inode *dir, struct dentry *dentry); 100 101 struct configfs_symlink { 102 struct list_head sl_list; 103 struct config_item *sl_target; 104 }; 105 106 extern int configfs_create_link(struct configfs_symlink *sl, 107 struct dentry *parent, 108 struct dentry *dentry); 109 110 static inline struct config_item * to_item(struct dentry * dentry) 111 { 112 struct configfs_dirent * sd = dentry->d_fsdata; 113 return ((struct config_item *) sd->s_element); 114 } 115 116 static inline struct configfs_attribute * to_attr(struct dentry * dentry) 117 { 118 struct configfs_dirent * sd = dentry->d_fsdata; 119 return ((struct configfs_attribute *) sd->s_element); 120 } 121 122 static inline struct config_item *configfs_get_config_item(struct dentry *dentry) 123 { 124 struct config_item * item = NULL; 125 126 spin_lock(&dentry->d_lock); 127 if (!d_unhashed(dentry)) { 128 struct configfs_dirent * sd = dentry->d_fsdata; 129 if (sd->s_type & CONFIGFS_ITEM_LINK) { 130 struct configfs_symlink * sl = sd->s_element; 131 item = config_item_get(sl->sl_target); 132 } else 133 item = config_item_get(sd->s_element); 134 } 135 spin_unlock(&dentry->d_lock); 136 137 return item; 138 } 139 140 static inline void release_configfs_dirent(struct configfs_dirent * sd) 141 { 142 if (!(sd->s_type & CONFIGFS_ROOT)) { 143 kfree(sd->s_iattr); 144 kmem_cache_free(configfs_dir_cachep, sd); 145 } 146 } 147 148 static inline struct configfs_dirent * configfs_get(struct configfs_dirent * sd) 149 { 150 if (sd) { 151 WARN_ON(!atomic_read(&sd->s_count)); 152 atomic_inc(&sd->s_count); 153 } 154 return sd; 155 } 156 157 static inline void configfs_put(struct configfs_dirent * sd) 158 { 159 WARN_ON(!atomic_read(&sd->s_count)); 160 if (atomic_dec_and_test(&sd->s_count)) 161 release_configfs_dirent(sd); 162 } 163 164