1 files changed, 82 insertions, 86 deletions

diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h
index 502c949c402d..6b8c8d76d308 100644
--- a/fs/sysfs/sysfs.h
+++ b/fs/sysfs/sysfs.h
@@ -1,9 +1,40 @@
+struct sysfs_elem_dir {
+	struct kobject		* kobj;
+};
+
+struct sysfs_elem_symlink {
+	struct sysfs_dirent	* target_sd;
+};
+
+struct sysfs_elem_attr {
+	struct attribute	* attr;
+};
+
+struct sysfs_elem_bin_attr {
+	struct bin_attribute	* bin_attr;
+};
+
+/*
+ * As long as s_count reference is held, the sysfs_dirent itself is
+ * accessible.  Dereferencing s_elem or any other outer entity
+ * requires s_active reference.
+ */
 struct sysfs_dirent {
 	atomic_t		s_count;
-	struct list_head	s_sibling;
-	struct list_head	s_children;
-	void 			* s_element;
-	int			s_type;
+	atomic_t		s_active;
+	struct sysfs_dirent	* s_parent;
+	struct sysfs_dirent	* s_sibling;
+	struct sysfs_dirent	* s_children;
+	const char		* s_name;
+
+	union {
+		struct sysfs_elem_dir		dir;
+		struct sysfs_elem_symlink	symlink;
+		struct sysfs_elem_attr		attr;
+		struct sysfs_elem_bin_attr	bin_attr;
+	}			s_elem;
+
+	unsigned int		s_flags;
 	umode_t			s_mode;
 	ino_t			s_ino;
 	struct dentry		* s_dentry;
@@ -11,30 +42,59 @@ struct sysfs_dirent {
 	atomic_t		s_event;
 };
 
+#define SD_DEACTIVATED_BIAS	INT_MIN
+
+struct sysfs_addrm_cxt {
+	struct sysfs_dirent	*parent_sd;
+	struct inode		*parent_inode;
+	struct sysfs_dirent	*removed;
+	int			cnt;
+};
+
 extern struct vfsmount * sysfs_mount;
+extern struct sysfs_dirent sysfs_root;
 extern struct kmem_cache *sysfs_dir_cachep;
 
-extern void sysfs_delete_inode(struct inode *inode);
-extern struct inode * sysfs_new_inode(mode_t mode, struct sysfs_dirent *);
-extern int sysfs_create(struct dentry *, int mode, int (*init)(struct inode *));
+extern struct dentry *sysfs_get_dentry(struct sysfs_dirent *sd);
+extern void sysfs_link_sibling(struct sysfs_dirent *sd);
+extern void sysfs_unlink_sibling(struct sysfs_dirent *sd);
+extern struct sysfs_dirent *sysfs_get_active(struct sysfs_dirent *sd);
+extern void sysfs_put_active(struct sysfs_dirent *sd);
+extern struct sysfs_dirent *sysfs_get_active_two(struct sysfs_dirent *sd);
+extern void sysfs_put_active_two(struct sysfs_dirent *sd);
+extern void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt,
+			      struct sysfs_dirent *parent_sd);
+extern void sysfs_add_one(struct sysfs_addrm_cxt *acxt,
+			  struct sysfs_dirent *sd);
+extern void sysfs_remove_one(struct sysfs_addrm_cxt *acxt,
+			     struct sysfs_dirent *sd);
+extern int sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt);
 
-extern int sysfs_dirent_exist(struct sysfs_dirent *, const unsigned char *);
-extern int sysfs_make_dirent(struct sysfs_dirent *, struct dentry *, void *,
-				umode_t, int);
-
-extern int sysfs_add_file(struct dentry *, const struct attribute *, int);
-extern int sysfs_hash_and_remove(struct dentry * dir, const char * name);
+extern void sysfs_delete_inode(struct inode *inode);
+extern struct inode * sysfs_get_inode(struct sysfs_dirent *sd);
+extern void sysfs_instantiate(struct dentry *dentry, struct inode *inode);
+
+extern void release_sysfs_dirent(struct sysfs_dirent * sd);
+extern struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd,
+					      const unsigned char *name);
+extern struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
+					     const unsigned char *name);
+extern struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode,
+					     int type);
+
+extern int sysfs_add_file(struct sysfs_dirent *dir_sd,
+			  const struct attribute *attr, int type);
+extern int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const char *name);
 extern struct sysfs_dirent *sysfs_find(struct sysfs_dirent *dir, const char * name);
 
-extern int sysfs_create_subdir(struct kobject *, const char *, struct dentry **);
-extern void sysfs_remove_subdir(struct dentry *);
+extern int sysfs_create_subdir(struct kobject *kobj, const char *name,
+			       struct sysfs_dirent **p_sd);
+extern void sysfs_remove_subdir(struct sysfs_dirent *sd);
 
-extern const unsigned char * sysfs_get_name(struct sysfs_dirent *sd);
-extern void sysfs_drop_dentry(struct sysfs_dirent *sd, struct dentry *parent);
 extern int sysfs_setattr(struct dentry *dentry, struct iattr *iattr);
 
-extern spinlock_t sysfs_lock;
-extern struct rw_semaphore sysfs_rename_sem;
+extern spinlock_t sysfs_assoc_lock;
+extern struct mutex sysfs_mutex;
 extern struct super_block * sysfs_sb;
 extern const struct file_operations sysfs_dir_operations;
 extern const struct file_operations sysfs_file_operations;
@@ -42,73 +102,9 @@ extern const struct file_operations bin_fops;
 extern const struct inode_operations sysfs_dir_inode_operations;
 extern const struct inode_operations sysfs_symlink_inode_operations;
 
-struct sysfs_symlink {
-	char * link_name;
-	struct kobject * target_kobj;
-};
-
-struct sysfs_buffer {
-	struct list_head		associates;
-	size_t				count;
-	loff_t				pos;
-	char				* page;
-	struct sysfs_ops		* ops;
-	struct semaphore		sem;
-	int				orphaned;
-	int				needs_read_fill;
-	int				event;
-};
-
-struct sysfs_buffer_collection {
-	struct list_head	associates;
-};
-
-static inline struct kobject * to_kobj(struct dentry * dentry)
-{
-	struct sysfs_dirent * sd = dentry->d_fsdata;
-	return ((struct kobject *) sd->s_element);
-}
-
-static inline struct attribute * to_attr(struct dentry * dentry)
+static inline unsigned int sysfs_type(struct sysfs_dirent *sd)
 {
-	struct sysfs_dirent * sd = dentry->d_fsdata;
-	return ((struct attribute *) sd->s_element);
-}
-
-static inline struct bin_attribute * to_bin_attr(struct dentry * dentry)
-{
-	struct sysfs_dirent * sd = dentry->d_fsdata;
-	return ((struct bin_attribute *) sd->s_element);
-}
-
-static inline struct kobject *sysfs_get_kobject(struct dentry *dentry)
-{
-	struct kobject * kobj = NULL;
-
-	spin_lock(&dcache_lock);
-	if (!d_unhashed(dentry)) {
-		struct sysfs_dirent * sd = dentry->d_fsdata;
-		if (sd->s_type & SYSFS_KOBJ_LINK) {
-			struct sysfs_symlink * sl = sd->s_element;
-			kobj = kobject_get(sl->target_kobj);
-		} else
-			kobj = kobject_get(sd->s_element);
-	}
-	spin_unlock(&dcache_lock);
-
-	return kobj;
-}
-
-static inline void release_sysfs_dirent(struct sysfs_dirent * sd)
-{
-	if (sd->s_type & SYSFS_KOBJ_LINK) {
-		struct sysfs_symlink * sl = sd->s_element;
-		kfree(sl->link_name);
-		kobject_put(sl->target_kobj);
-		kfree(sl);
-	}
-	kfree(sd->s_iattr);
-	kmem_cache_free(sysfs_dir_cachep, sd);
+	return sd->s_flags & SYSFS_TYPE_MASK;
 }
 
 static inline struct sysfs_dirent * sysfs_get(struct sysfs_dirent * sd)
@@ -122,7 +118,7 @@ static inline struct sysfs_dirent * sysfs_get(struct sysfs_dirent * sd)
 
 static inline void sysfs_put(struct sysfs_dirent * sd)
 {
-	if (atomic_dec_and_test(&sd->s_count))
+	if (sd && atomic_dec_and_test(&sd->s_count))
 		release_sysfs_dirent(sd);
 }