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