fs/sysfs/sysfs.h

   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 #include <linux/lockdep.h>
  12 #include <linux/fs.h>
  13
  14 struct sysfs_open_dirent;
  15
  16 /* type-specific structures for sysfs_dirent->s_* union members */
  17 struct sysfs_elem_dir {
  18         struct kobject          *kobj;
  19         /* children list starts here and goes through sd->s_sibling */
  20         struct sysfs_dirent     *children;
  21 };
  22
  23 struct sysfs_elem_symlink {
  24         struct sysfs_dirent     *target_sd;
  25 };
  26
  27 struct sysfs_elem_attr {
  28         struct attribute        *attr;
  29         struct sysfs_open_dirent *open;
  30 };
  31
  32 struct sysfs_elem_bin_attr {
  33         struct bin_attribute    *bin_attr;
  34         struct hlist_head       buffers;
  35 };
  36
  37 struct sysfs_inode_attrs {
  38         struct iattr    ia_iattr;
  39         void            *ia_secdata;
  40         u32             ia_secdata_len;
  41 };
  42
  43 /*
  44  * sysfs_dirent - the building block of sysfs hierarchy.  Each and
  45  * every sysfs node is represented by single sysfs_dirent.
  46  *
  47  * As long as s_count reference is held, the sysfs_dirent itself is
  48  * accessible.  Dereferencing s_elem or any other outer entity
  49  * requires s_active reference.
  50  */
  51 struct sysfs_dirent {
  52         atomic_t                s_count;
  53         atomic_t                s_active;
  54 #ifdef CONFIG_DEBUG_LOCK_ALLOC
  55         struct lockdep_map      dep_map;
  56 #endif
  57         struct sysfs_dirent     *s_parent;
  58         struct sysfs_dirent     *s_sibling;
  59         const char              *s_name;
  60
  61         union {
  62                 struct sysfs_elem_dir           s_dir;
  63                 struct sysfs_elem_symlink       s_symlink;
  64                 struct sysfs_elem_attr          s_attr;
  65                 struct sysfs_elem_bin_attr      s_bin_attr;
  66         };
  67
  68         unsigned int            s_flags;
  69         unsigned short          s_mode;
  70         ino_t                   s_ino;
  71         struct sysfs_inode_attrs *s_iattr;
  72 };
  73
  74 #define SD_DEACTIVATED_BIAS             INT_MIN
  75
  76 #define SYSFS_TYPE_MASK                 0x00ff
  77 #define SYSFS_DIR                       0x0001
  78 #define SYSFS_KOBJ_ATTR                 0x0002
  79 #define SYSFS_KOBJ_BIN_ATTR             0x0004
  80 #define SYSFS_KOBJ_LINK                 0x0008
  81 #define SYSFS_COPY_NAME                 (SYSFS_DIR | SYSFS_KOBJ_LINK)
  82 #define SYSFS_ACTIVE_REF                (SYSFS_KOBJ_ATTR | SYSFS_KOBJ_BIN_ATTR)
  83
  84 #define SYSFS_FLAG_MASK                 ~SYSFS_TYPE_MASK
  85 #define SYSFS_FLAG_REMOVED              0x0200
  86
  87 static inline unsigned int sysfs_type(struct sysfs_dirent *sd)
  88 {
  89         return sd->s_flags & SYSFS_TYPE_MASK;
  90 }
  91
  92 #ifdef CONFIG_DEBUG_LOCK_ALLOC
  93 #define sysfs_dirent_init_lockdep(sd)                           \
  94 do {                                                            \
  95         struct attribute *attr = sd->s_attr.attr;               \
  96         struct lock_class_key *key = attr->key;                 \
  97         if (!key)                                               \
  98                 key = &attr->skey;                              \
  99                                                                 \
 100         lockdep_init_map(&sd->dep_map, "s_active", key, 0);     \
 101 } while(0)
 102 #else
 103 #define sysfs_dirent_init_lockdep(sd) do {} while(0)
 104 #endif
 105
 106 /*
 107  * Context structure to be used while adding/removing nodes.
 108  */
 109 struct sysfs_addrm_cxt {
 110         struct sysfs_dirent     *parent_sd;
 111         struct sysfs_dirent     *removed;
 112 };
 113
 114 /*
 115  * mount.c
 116  */
 117 extern struct sysfs_dirent sysfs_root;
 118 extern struct kmem_cache *sysfs_dir_cachep;
 119
 120 /*
 121  * dir.c
 122  */
 123 extern struct mutex sysfs_mutex;
 124 extern spinlock_t sysfs_assoc_lock;
 125
 126 extern const struct file_operations sysfs_dir_operations;
 127 extern const struct inode_operations sysfs_dir_inode_operations;
 128
 129 struct dentry *sysfs_get_dentry(struct sysfs_dirent *sd);
 130 struct sysfs_dirent *sysfs_get_active(struct sysfs_dirent *sd);
 131 void sysfs_put_active(struct sysfs_dirent *sd);
 132 void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt,
 133                        struct sysfs_dirent *parent_sd);
 134 int __sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd);
 135 int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd);
 136 void sysfs_remove_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd);
 137 void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt);
 138
 139 struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd,
 140                                        const unsigned char *name);
 141 struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
 142                                       const unsigned char *name);
 143 struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode, int type);
 144
 145 void release_sysfs_dirent(struct sysfs_dirent *sd);
 146
 147 int sysfs_create_subdir(struct kobject *kobj, const char *name,
 148                         struct sysfs_dirent **p_sd);
 149 void sysfs_remove_subdir(struct sysfs_dirent *sd);
 150
 151 int sysfs_rename(struct sysfs_dirent *sd,
 152         struct sysfs_dirent *new_parent_sd, const char *new_name);
 153
 154 static inline struct sysfs_dirent *__sysfs_get(struct sysfs_dirent *sd)
 155 {
 156         if (sd) {
 157                 WARN_ON(!atomic_read(&sd->s_count));
 158                 atomic_inc(&sd->s_count);
 159         }
 160         return sd;
 161 }
 162 #define sysfs_get(sd) __sysfs_get(sd)
 163
 164 static inline void __sysfs_put(struct sysfs_dirent *sd)
 165 {
 166         if (sd && atomic_dec_and_test(&sd->s_count))
 167                 release_sysfs_dirent(sd);
 168 }
 169 #define sysfs_put(sd) __sysfs_put(sd)
 170
 171 /*
 172  * inode.c
 173  */
 174 struct inode *sysfs_get_inode(struct super_block *sb, struct sysfs_dirent *sd);
 175 void sysfs_delete_inode(struct inode *inode);
 176 int sysfs_sd_setattr(struct sysfs_dirent *sd, struct iattr *iattr);
 177 int sysfs_permission(struct inode *inode, int mask);
 178 int sysfs_setattr(struct dentry *dentry, struct iattr *iattr);
 179 int sysfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat);
 180 int sysfs_setxattr(struct dentry *dentry, const char *name, const void *value,
 181                 size_t size, int flags);
 182 int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const char *name);
 183 int sysfs_inode_init(void);
 184
 185 /*
 186  * file.c
 187  */
 188 extern const struct file_operations sysfs_file_operations;
 189
 190 int sysfs_add_file(struct sysfs_dirent *dir_sd,
 191                    const struct attribute *attr, int type);
 192
 193 int sysfs_add_file_mode(struct sysfs_dirent *dir_sd,
 194                         const struct attribute *attr, int type, mode_t amode);
 195 /*
 196  * bin.c
 197  */
 198 extern const struct file_operations bin_fops;
 199 void unmap_bin_file(struct sysfs_dirent *attr_sd);
 200
 201 /*
 202  * symlink.c
 203  */
 204 extern const struct inode_operations sysfs_symlink_inode_operations;