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 int s_dependent_count; 33 struct list_head s_sibling; 34 struct list_head s_children; 35 struct list_head 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 }; 42 43 #define CONFIGFS_ROOT 0x0001 44 #define CONFIGFS_DIR 0x0002 45 #define CONFIGFS_ITEM_ATTR 0x0004 46 #define CONFIGFS_ITEM_LINK 0x0020 47 #define CONFIGFS_USET_DIR 0x0040 48 #define CONFIGFS_USET_DEFAULT 0x0080 49 #define CONFIGFS_USET_DROPPING 0x0100 50 #define CONFIGFS_NOT_PINNED (CONFIGFS_ITEM_ATTR) 51 52 extern struct vfsmount * configfs_mount; 53 extern struct kmem_cache *configfs_dir_cachep; 54 55 extern int configfs_is_root(struct config_item *item); 56 57 extern struct inode * configfs_new_inode(mode_t mode, struct configfs_dirent *); 58 extern int configfs_create(struct dentry *, int mode, int (*init)(struct inode *)); 59 60 extern int configfs_create_file(struct config_item *, const struct configfs_attribute *); 61 extern int configfs_make_dirent(struct configfs_dirent *, 62 struct dentry *, void *, umode_t, int); 63 64 extern int configfs_add_file(struct dentry *, const struct configfs_attribute *, int); 65 extern void configfs_hash_and_remove(struct dentry * dir, const char * name); 66 67 extern const unsigned char * configfs_get_name(struct configfs_dirent *sd); 68 extern void configfs_drop_dentry(struct configfs_dirent *sd, struct dentry *parent); 69 extern int configfs_setattr(struct dentry *dentry, struct iattr *iattr); 70 71 extern int configfs_pin_fs(void); 72 extern void configfs_release_fs(void); 73 74 extern struct rw_semaphore configfs_rename_sem; 75 extern struct super_block * configfs_sb; 76 extern const struct file_operations configfs_dir_operations; 77 extern const struct file_operations configfs_file_operations; 78 extern const struct file_operations bin_fops; 79 extern const struct inode_operations configfs_dir_inode_operations; 80 extern const struct inode_operations configfs_symlink_inode_operations; 81 82 extern int configfs_symlink(struct inode *dir, struct dentry *dentry, 83 const char *symname); 84 extern int configfs_unlink(struct inode *dir, struct dentry *dentry); 85 86 struct configfs_symlink { 87 struct list_head sl_list; 88 struct config_item *sl_target; 89 }; 90 91 extern int configfs_create_link(struct configfs_symlink *sl, 92 struct dentry *parent, 93 struct dentry *dentry); 94 95 static inline struct config_item * to_item(struct dentry * dentry) 96 { 97 struct configfs_dirent * sd = dentry->d_fsdata; 98 return ((struct config_item *) sd->s_element); 99 } 100 101 static inline struct configfs_attribute * to_attr(struct dentry * dentry) 102 { 103 struct configfs_dirent * sd = dentry->d_fsdata; 104 return ((struct configfs_attribute *) sd->s_element); 105 } 106 107 static inline struct config_item *configfs_get_config_item(struct dentry *dentry) 108 { 109 struct config_item * item = NULL; 110 111 spin_lock(&dcache_lock); 112 if (!d_unhashed(dentry)) { 113 struct configfs_dirent * sd = dentry->d_fsdata; 114 if (sd->s_type & CONFIGFS_ITEM_LINK) { 115 struct configfs_symlink * sl = sd->s_element; 116 item = config_item_get(sl->sl_target); 117 } else 118 item = config_item_get(sd->s_element); 119 } 120 spin_unlock(&dcache_lock); 121 122 return item; 123 } 124 125 static inline void release_configfs_dirent(struct configfs_dirent * sd) 126 { 127 if (!(sd->s_type & CONFIGFS_ROOT)) { 128 kfree(sd->s_iattr); 129 kmem_cache_free(configfs_dir_cachep, sd); 130 } 131 } 132 133 static inline struct configfs_dirent * configfs_get(struct configfs_dirent * sd) 134 { 135 if (sd) { 136 WARN_ON(!atomic_read(&sd->s_count)); 137 atomic_inc(&sd->s_count); 138 } 139 return sd; 140 } 141 142 static inline void configfs_put(struct configfs_dirent * sd) 143 { 144 WARN_ON(!atomic_read(&sd->s_count)); 145 if (atomic_dec_and_test(&sd->s_count)) 146 release_configfs_dirent(sd); 147 } 148 149