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 struct sysfs_super_info {
 118 };
 119 #define sysfs_info(SB) ((struct sysfs_super_info *)(SB->s_fs_info))
 120 extern struct sysfs_dirent sysfs_root;
 121 extern struct kmem_cache *sysfs_dir_cachep;
 122
 123 /*
 124  * dir.c
 125  */
 126 extern struct mutex sysfs_mutex;
 127 extern spinlock_t sysfs_assoc_lock;
 128
 129 extern const struct file_operations sysfs_dir_operations;
 130 extern const struct inode_operations sysfs_dir_inode_operations;
 131
 132 struct dentry *sysfs_get_dentry(struct sysfs_dirent *sd);
 133 struct sysfs_dirent *sysfs_get_active(struct sysfs_dirent *sd);
 134 void sysfs_put_active(struct sysfs_dirent *sd);
 135 void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt,
 136                        struct sysfs_dirent *parent_sd);
 137 int __sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd);
 138 int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd);
 139 void sysfs_remove_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd);
 140 void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt);
 141
 142 struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd,
 143                                        const unsigned char *name);
 144 struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
 145                                       const unsigned char *name);
 146 struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode, int type);
 147
 148 void release_sysfs_dirent(struct sysfs_dirent *sd);
 149
 150 int sysfs_create_subdir(struct kobject *kobj, const char *name,
 151                         struct sysfs_dirent **p_sd);
 152 void sysfs_remove_subdir(struct sysfs_dirent *sd);
 153
 154 int sysfs_rename(struct sysfs_dirent *sd,
 155         struct sysfs_dirent *new_parent_sd, const char *new_name);
 156
 157 static inline struct sysfs_dirent *__sysfs_get(struct sysfs_dirent *sd)
 158 {
 159         if (sd) {
 160                 WARN_ON(!atomic_read(&sd->s_count));
 161                 atomic_inc(&sd->s_count);
 162         }
 163         return sd;
 164 }
 165 #define sysfs_get(sd) __sysfs_get(sd)
 166
 167 static inline void __sysfs_put(struct sysfs_dirent *sd)
 168 {
 169         if (sd && atomic_dec_and_test(&sd->s_count))
 170                 release_sysfs_dirent(sd);
 171 }
 172 #define sysfs_put(sd) __sysfs_put(sd)
 173
 174 /*
 175  * inode.c
 176  */
 177 struct inode *sysfs_get_inode(struct super_block *sb, struct sysfs_dirent *sd);
 178 void sysfs_delete_inode(struct inode *inode);
 179 int sysfs_sd_setattr(struct sysfs_dirent *sd, struct iattr *iattr);
 180 int sysfs_permission(struct inode *inode, int mask);
 181 int sysfs_setattr(struct dentry *dentry, struct iattr *iattr);
 182 int sysfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat);
 183 int sysfs_setxattr(struct dentry *dentry, const char *name, const void *value,
 184                 size_t size, int flags);
 185 int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const char *name);
 186 int sysfs_inode_init(void);
 187
 188 /*
 189  * file.c
 190  */
 191 extern const struct file_operations sysfs_file_operations;
 192
 193 int sysfs_add_file(struct sysfs_dirent *dir_sd,
 194                    const struct attribute *attr, int type);
 195
 196 int sysfs_add_file_mode(struct sysfs_dirent *dir_sd,
 197                         const struct attribute *attr, int type, mode_t amode);
 198 /*
 199  * bin.c
 200  */
 201 extern const struct file_operations bin_fops;
 202 void unmap_bin_file(struct sysfs_dirent *attr_sd);
 203
 204 /*
 205  * symlink.c
 206  */
 207 extern const struct inode_operations sysfs_symlink_inode_operations;