mm: bdi init hooks

provide BDI constructor/destructor hooks

[akpm@linux-foundation.org: compile fix]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/sysfs/inode.c

@@ -37,6 +37,11 @@ static const struct inode_operations sysfs_inode_operations ={
 	.setattr	= sysfs_setattr,
 };
 
+int __init sysfs_inode_init(void)
+{
+	return bdi_init(&sysfs_backing_dev_info);
+}
+
 int sysfs_setattr(struct dentry * dentry, struct iattr * iattr)
 {
 	struct inode * inode = dentry->d_inode;

fs/sysfs/mount.c

@@ -92,6 +92,10 @@ int __init sysfs_init(void)
 	if (!sysfs_dir_cachep)
 		goto out;
 
+	err = sysfs_inode_init();
+	if (err)
+		goto out_err;
+
 	err = register_filesystem(&sysfs_fs_type);
 	if (!err) {
 		sysfs_mount = kern_mount(&sysfs_fs_type);

fs/sysfs/sysfs.h

@@ -146,6 +146,7 @@ static inline void sysfs_put(struct sysfs_dirent *sd)
 struct inode *sysfs_get_inode(struct sysfs_dirent *sd);
 int sysfs_setattr(struct dentry *dentry, struct iattr *iattr);
 int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const char *name);
+int sysfs_inode_init(void);
 
 /*
  * file.c