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 #include <linux/slab.h> 28 #include <linux/list.h> 29 #include <linux/spinlock.h> 30 31 struct configfs_dirent { 32 atomic_t s_count; 33 int s_dependent_count; 34 struct list_head s_sibling; 35 struct list_head s_children; 36 struct list_head s_links; 37 void * s_element; 38 int s_type; 39 umode_t s_mode; 40 struct dentry * s_dentry; 41 struct iattr * s_iattr; 42 #ifdef CONFIG_LOCKDEP 43 int s_depth; 44 #endif 45 }; 46 47 #define CONFIGFS_ROOT 0x0001 48 #define CONFIGFS_DIR 0x0002 49 #define CONFIGFS_ITEM_ATTR 0x0004 50 #define CONFIGFS_ITEM_LINK 0x0020 51 #define CONFIGFS_USET_DIR 0x0040 52 #define CONFIGFS_USET_DEFAULT 0x0080 53 #define CONFIGFS_USET_DROPPING 0x0100 54 #define CONFIGFS_USET_IN_MKDIR 0x0200 55 #define CONFIGFS_USET_CREATING 0x0400 56 #define CONFIGFS_NOT_PINNED (CONFIGFS_ITEM_ATTR) 57 58 extern struct mutex configfs_symlink_mutex; 59 extern spinlock_t configfs_dirent_lock; 60 61 extern struct kmem_cache *configfs_dir_cachep; 62 63 extern int configfs_is_root(struct config_item *item); 64 65 extern struct inode * configfs_new_inode(umode_t mode, struct configfs_dirent *, struct super_block *); 66 extern int configfs_create(struct dentry *, umode_t mode, int (*init)(struct inode *)); 67 extern int configfs_inode_init(void); 68 extern void configfs_inode_exit(void); 69 70 extern int configfs_create_file(struct config_item *, const struct configfs_attribute *); 71 extern int configfs_make_dirent(struct configfs_dirent *, 72 struct dentry *, void *, umode_t, int); 73 extern int configfs_dirent_is_ready(struct configfs_dirent *); 74 75 extern int configfs_add_file(struct dentry *, const struct configfs_attribute *, int); 76 extern void configfs_hash_and_remove(struct dentry * dir, const char * name); 77 78 extern const unsigned char * configfs_get_name(struct configfs_dirent *sd); 79 extern void configfs_drop_dentry(struct configfs_dirent *sd, struct dentry *parent); 80 extern int configfs_setattr(struct dentry *dentry, struct iattr *iattr); 81 82 extern struct dentry *configfs_pin_fs(void); 83 extern void configfs_release_fs(void); 84 85 extern struct rw_semaphore configfs_rename_sem; 86 extern const struct file_operations configfs_dir_operations; 87 extern const struct file_operations configfs_file_operations; 88 extern const struct file_operations bin_fops; 89 extern const struct inode_operations configfs_dir_inode_operations; 90 extern const struct inode_operations configfs_root_inode_operations; 91 extern const struct inode_operations configfs_symlink_inode_operations; 92 extern const struct dentry_operations configfs_dentry_ops; 93 94 extern int configfs_symlink(struct inode *dir, struct dentry *dentry, 95 const char *symname); 96 extern int configfs_unlink(struct inode *dir, struct dentry *dentry); 97 98 struct configfs_symlink { 99 struct list_head sl_list; 100 struct config_item *sl_target; 101 }; 102 103 extern int configfs_create_link(struct configfs_symlink *sl, 104 struct dentry *parent, 105 struct dentry *dentry); 106 107 static inline struct config_item * to_item(struct dentry * dentry) 108 { 109 struct configfs_dirent * sd = dentry->d_fsdata; 110 return ((struct config_item *) sd->s_element); 111 } 112 113 static inline struct configfs_attribute * to_attr(struct dentry * dentry) 114 { 115 struct configfs_dirent * sd = dentry->d_fsdata; 116 return ((struct configfs_attribute *) sd->s_element); 117 } 118 119 static inline struct config_item *configfs_get_config_item(struct dentry *dentry) 120 { 121 struct config_item * item = NULL; 122 123 spin_lock(&dentry->d_lock); 124 if (!d_unhashed(dentry)) { 125 struct configfs_dirent * sd = dentry->d_fsdata; 126 if (sd->s_type & CONFIGFS_ITEM_LINK) { 127 struct configfs_symlink * sl = sd->s_element; 128 item = config_item_get(sl->sl_target); 129 } else 130 item = config_item_get(sd->s_element); 131 } 132 spin_unlock(&dentry->d_lock); 133 134 return item; 135 } 136 137 static inline void release_configfs_dirent(struct configfs_dirent * sd) 138 { 139 if (!(sd->s_type & CONFIGFS_ROOT)) { 140 kfree(sd->s_iattr); 141 kmem_cache_free(configfs_dir_cachep, sd); 142 } 143 } 144 145 static inline struct configfs_dirent * configfs_get(struct configfs_dirent * sd) 146 { 147 if (sd) { 148 WARN_ON(!atomic_read(&sd->s_count)); 149 atomic_inc(&sd->s_count); 150 } 151 return sd; 152 } 153 154 static inline void configfs_put(struct configfs_dirent * sd) 155 { 156 WARN_ON(!atomic_read(&sd->s_count)); 157 if (atomic_dec_and_test(&sd->s_count)) 158 release_configfs_dirent(sd); 159 } 160 161