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 30 struct configfs_dirent { 31 atomic_t s_count; 32 struct list_head s_sibling; 33 struct list_head s_children; 34 struct list_head s_links; 35 void * s_element; 36 int s_type; 37 umode_t s_mode; 38 struct dentry * s_dentry; 39 }; 40 41 #define CONFIGFS_ROOT 0x0001 42 #define CONFIGFS_DIR 0x0002 43 #define CONFIGFS_ITEM_ATTR 0x0004 44 #define CONFIGFS_ITEM_LINK 0x0020 45 #define CONFIGFS_USET_DIR 0x0040 46 #define CONFIGFS_USET_DEFAULT 0x0080 47 #define CONFIGFS_USET_DROPPING 0x0100 48 #define CONFIGFS_NOT_PINNED (CONFIGFS_ITEM_ATTR) 49 50 extern struct vfsmount * configfs_mount; 51 52 extern int configfs_is_root(struct config_item *item); 53 54 extern struct inode * configfs_new_inode(mode_t mode); 55 extern int configfs_create(struct dentry *, int mode, int (*init)(struct inode *)); 56 57 extern int configfs_create_file(struct config_item *, const struct configfs_attribute *); 58 extern int configfs_make_dirent(struct configfs_dirent *, 59 struct dentry *, void *, umode_t, int); 60 61 extern int configfs_add_file(struct dentry *, const struct configfs_attribute *, int); 62 extern void configfs_hash_and_remove(struct dentry * dir, const char * name); 63 64 extern const unsigned char * configfs_get_name(struct configfs_dirent *sd); 65 extern void configfs_drop_dentry(struct configfs_dirent *sd, struct dentry *parent); 66 67 extern int configfs_pin_fs(void); 68 extern void configfs_release_fs(void); 69 70 extern struct rw_semaphore configfs_rename_sem; 71 extern struct super_block * configfs_sb; 72 extern struct file_operations configfs_dir_operations; 73 extern struct file_operations configfs_file_operations; 74 extern struct file_operations bin_fops; 75 extern struct inode_operations configfs_dir_inode_operations; 76 extern struct inode_operations configfs_symlink_inode_operations; 77 78 extern int configfs_symlink(struct inode *dir, struct dentry *dentry, 79 const char *symname); 80 extern int configfs_unlink(struct inode *dir, struct dentry *dentry); 81 82 struct configfs_symlink { 83 struct list_head sl_list; 84 struct config_item *sl_target; 85 }; 86 87 extern int configfs_create_link(struct configfs_symlink *sl, 88 struct dentry *parent, 89 struct dentry *dentry); 90 91 static inline struct config_item * to_item(struct dentry * dentry) 92 { 93 struct configfs_dirent * sd = dentry->d_fsdata; 94 return ((struct config_item *) sd->s_element); 95 } 96 97 static inline struct configfs_attribute * to_attr(struct dentry * dentry) 98 { 99 struct configfs_dirent * sd = dentry->d_fsdata; 100 return ((struct configfs_attribute *) sd->s_element); 101 } 102 103 static inline struct config_item *configfs_get_config_item(struct dentry *dentry) 104 { 105 struct config_item * item = NULL; 106 107 spin_lock(&dcache_lock); 108 if (!d_unhashed(dentry)) { 109 struct configfs_dirent * sd = dentry->d_fsdata; 110 if (sd->s_type & CONFIGFS_ITEM_LINK) { 111 struct configfs_symlink * sl = sd->s_element; 112 item = config_item_get(sl->sl_target); 113 } else 114 item = config_item_get(sd->s_element); 115 } 116 spin_unlock(&dcache_lock); 117 118 return item; 119 } 120 121 static inline void release_configfs_dirent(struct configfs_dirent * sd) 122 { 123 if (!(sd->s_type & CONFIGFS_ROOT)) 124 kfree(sd); 125 } 126 127 static inline struct configfs_dirent * configfs_get(struct configfs_dirent * sd) 128 { 129 if (sd) { 130 WARN_ON(!atomic_read(&sd->s_count)); 131 atomic_inc(&sd->s_count); 132 } 133 return sd; 134 } 135 136 static inline void configfs_put(struct configfs_dirent * sd) 137 { 138 WARN_ON(!atomic_read(&sd->s_count)); 139 if (atomic_dec_and_test(&sd->s_count)) 140 release_configfs_dirent(sd); 141 } 142 143