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 struct iattr * s_iattr; 40 }; 41 42 #define CONFIGFS_ROOT 0x0001 43 #define CONFIGFS_DIR 0x0002 44 #define CONFIGFS_ITEM_ATTR 0x0004 45 #define CONFIGFS_ITEM_LINK 0x0020 46 #define CONFIGFS_USET_DIR 0x0040 47 #define CONFIGFS_USET_DEFAULT 0x0080 48 #define CONFIGFS_USET_DROPPING 0x0100 49 #define CONFIGFS_NOT_PINNED (CONFIGFS_ITEM_ATTR) 50 51 extern struct vfsmount * configfs_mount; 52 extern struct kmem_cache *configfs_dir_cachep; 53 54 extern int configfs_is_root(struct config_item *item); 55 56 extern struct inode * configfs_new_inode(mode_t mode, struct configfs_dirent *); 57 extern int configfs_create(struct dentry *, int mode, int (*init)(struct inode *)); 58 59 extern int configfs_create_file(struct config_item *, const struct configfs_attribute *); 60 extern int configfs_make_dirent(struct configfs_dirent *, 61 struct dentry *, void *, umode_t, int); 62 63 extern int configfs_add_file(struct dentry *, const struct configfs_attribute *, int); 64 extern void configfs_hash_and_remove(struct dentry * dir, const char * name); 65 66 extern const unsigned char * configfs_get_name(struct configfs_dirent *sd); 67 extern void configfs_drop_dentry(struct configfs_dirent *sd, struct dentry *parent); 68 extern int configfs_setattr(struct dentry *dentry, struct iattr *iattr); 69 70 extern int configfs_pin_fs(void); 71 extern void configfs_release_fs(void); 72 73 extern struct rw_semaphore configfs_rename_sem; 74 extern struct super_block * configfs_sb; 75 extern const struct file_operations configfs_dir_operations; 76 extern const struct file_operations configfs_file_operations; 77 extern const struct file_operations bin_fops; 78 extern const struct inode_operations configfs_dir_inode_operations; 79 extern const struct inode_operations configfs_symlink_inode_operations; 80 81 extern int configfs_symlink(struct inode *dir, struct dentry *dentry, 82 const char *symname); 83 extern int configfs_unlink(struct inode *dir, struct dentry *dentry); 84 85 struct configfs_symlink { 86 struct list_head sl_list; 87 struct config_item *sl_target; 88 }; 89 90 extern int configfs_create_link(struct configfs_symlink *sl, 91 struct dentry *parent, 92 struct dentry *dentry); 93 94 static inline struct config_item * to_item(struct dentry * dentry) 95 { 96 struct configfs_dirent * sd = dentry->d_fsdata; 97 return ((struct config_item *) sd->s_element); 98 } 99 100 static inline struct configfs_attribute * to_attr(struct dentry * dentry) 101 { 102 struct configfs_dirent * sd = dentry->d_fsdata; 103 return ((struct configfs_attribute *) sd->s_element); 104 } 105 106 static inline struct config_item *configfs_get_config_item(struct dentry *dentry) 107 { 108 struct config_item * item = NULL; 109 110 spin_lock(&dcache_lock); 111 if (!d_unhashed(dentry)) { 112 struct configfs_dirent * sd = dentry->d_fsdata; 113 if (sd->s_type & CONFIGFS_ITEM_LINK) { 114 struct configfs_symlink * sl = sd->s_element; 115 item = config_item_get(sl->sl_target); 116 } else 117 item = config_item_get(sd->s_element); 118 } 119 spin_unlock(&dcache_lock); 120 121 return item; 122 } 123 124 static inline void release_configfs_dirent(struct configfs_dirent * sd) 125 { 126 if (!(sd->s_type & CONFIGFS_ROOT)) { 127 kfree(sd->s_iattr); 128 kmem_cache_free(configfs_dir_cachep, sd); 129 } 130 } 131 132 static inline struct configfs_dirent * configfs_get(struct configfs_dirent * sd) 133 { 134 if (sd) { 135 WARN_ON(!atomic_read(&sd->s_count)); 136 atomic_inc(&sd->s_count); 137 } 138 return sd; 139 } 140 141 static inline void configfs_put(struct configfs_dirent * sd) 142 { 143 WARN_ON(!atomic_read(&sd->s_count)); 144 if (atomic_dec_and_test(&sd->s_count)) 145 release_configfs_dirent(sd); 146 } 147 148