1 /* 2 * fs/sysfs/sysfs.h - sysfs internal header file 3 * 4 * Copyright (c) 2001-3 Patrick Mochel 5 * Copyright (c) 2007 SUSE Linux Products GmbH 6 * Copyright (c) 2007 Tejun Heo <teheo@suse.de> 7 * 8 * This file is released under the GPLv2. 9 */ 10 11 struct sysfs_open_dirent; 12 13 /* type-specific structures for sysfs_dirent->s_* union members */ 14 struct sysfs_elem_dir { 15 struct kobject *kobj; 16 /* children list starts here and goes through sd->s_sibling */ 17 struct sysfs_dirent *children; 18 }; 19 20 struct sysfs_elem_symlink { 21 struct sysfs_dirent *target_sd; 22 }; 23 24 struct sysfs_elem_attr { 25 struct attribute *attr; 26 struct sysfs_open_dirent *open; 27 }; 28 29 struct sysfs_elem_bin_attr { 30 struct bin_attribute *bin_attr; 31 }; 32 33 /* 34 * sysfs_dirent - the building block of sysfs hierarchy. Each and 35 * every sysfs node is represented by single sysfs_dirent. 36 * 37 * As long as s_count reference is held, the sysfs_dirent itself is 38 * accessible. Dereferencing s_elem or any other outer entity 39 * requires s_active reference. 40 */ 41 struct sysfs_dirent { 42 atomic_t s_count; 43 atomic_t s_active; 44 struct sysfs_dirent *s_parent; 45 struct sysfs_dirent *s_sibling; 46 const char *s_name; 47 48 union { 49 struct sysfs_elem_dir s_dir; 50 struct sysfs_elem_symlink s_symlink; 51 struct sysfs_elem_attr s_attr; 52 struct sysfs_elem_bin_attr s_bin_attr; 53 }; 54 55 unsigned int s_flags; 56 ino_t s_ino; 57 umode_t s_mode; 58 struct iattr *s_iattr; 59 }; 60 61 #define SD_DEACTIVATED_BIAS INT_MIN 62 63 #define SYSFS_TYPE_MASK 0x00ff 64 #define SYSFS_DIR 0x0001 65 #define SYSFS_KOBJ_ATTR 0x0002 66 #define SYSFS_KOBJ_BIN_ATTR 0x0004 67 #define SYSFS_KOBJ_LINK 0x0008 68 #define SYSFS_COPY_NAME (SYSFS_DIR | SYSFS_KOBJ_LINK) 69 70 #define SYSFS_FLAG_MASK ~SYSFS_TYPE_MASK 71 #define SYSFS_FLAG_REMOVED 0x0200 72 73 static inline unsigned int sysfs_type(struct sysfs_dirent *sd) 74 { 75 return sd->s_flags & SYSFS_TYPE_MASK; 76 } 77 78 /* 79 * Context structure to be used while adding/removing nodes. 80 */ 81 struct sysfs_addrm_cxt { 82 struct sysfs_dirent *parent_sd; 83 struct inode *parent_inode; 84 struct sysfs_dirent *removed; 85 int cnt; 86 }; 87 88 /* 89 * mount.c 90 */ 91 extern struct sysfs_dirent sysfs_root; 92 extern struct super_block *sysfs_sb; 93 extern struct kmem_cache *sysfs_dir_cachep; 94 95 /* 96 * dir.c 97 */ 98 extern struct mutex sysfs_mutex; 99 extern struct mutex sysfs_rename_mutex; 100 extern spinlock_t sysfs_assoc_lock; 101 102 extern const struct file_operations sysfs_dir_operations; 103 extern const struct inode_operations sysfs_dir_inode_operations; 104 105 struct dentry *sysfs_get_dentry(struct sysfs_dirent *sd); 106 struct sysfs_dirent *sysfs_get_active_two(struct sysfs_dirent *sd); 107 void sysfs_put_active_two(struct sysfs_dirent *sd); 108 void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt, 109 struct sysfs_dirent *parent_sd); 110 int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd); 111 void sysfs_remove_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd); 112 void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt); 113 114 struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd, 115 const unsigned char *name); 116 struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd, 117 const unsigned char *name); 118 struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode, int type); 119 120 void release_sysfs_dirent(struct sysfs_dirent *sd); 121 122 int sysfs_create_subdir(struct kobject *kobj, const char *name, 123 struct sysfs_dirent **p_sd); 124 void sysfs_remove_subdir(struct sysfs_dirent *sd); 125 126 static inline struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd) 127 { 128 if (sd) { 129 WARN_ON(!atomic_read(&sd->s_count)); 130 atomic_inc(&sd->s_count); 131 } 132 return sd; 133 } 134 135 static inline void sysfs_put(struct sysfs_dirent *sd) 136 { 137 if (sd && atomic_dec_and_test(&sd->s_count)) 138 release_sysfs_dirent(sd); 139 } 140 141 /* 142 * inode.c 143 */ 144 struct inode *sysfs_get_inode(struct sysfs_dirent *sd); 145 int sysfs_setattr(struct dentry *dentry, struct iattr *iattr); 146 int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const char *name); 147 int sysfs_inode_init(void); 148 149 /* 150 * file.c 151 */ 152 extern const struct file_operations sysfs_file_operations; 153 154 int sysfs_add_file(struct sysfs_dirent *dir_sd, 155 const struct attribute *attr, int type); 156 157 /* 158 * bin.c 159 */ 160 extern const struct file_operations bin_fops; 161 162 /* 163 * symlink.c 164 */ 165 extern const struct inode_operations sysfs_symlink_inode_operations; 166