f2fs: fix i_blocks translation on various types of files

Basically an inode manages the number of allocated blocks with inode->i_blocks
which is represented in a unit of sectors, not file system blocks.
But, f2fs has used i_blocks in a unit of file system blocks, and f2fs_getattr
translates it to the number of sectors when fstat is called.

However, previously f2fs_file_inode_operations only has this, so this patch adds
it to all the types of inode_operations.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

fs/f2fs/f2fs.h

@@ -903,6 +903,7 @@ static inline int f2fs_readonly(struct super_block *sb)
 int f2fs_sync_file(struct file *, loff_t, loff_t, int);
 void truncate_data_blocks(struct dnode_of_data *);
 void f2fs_truncate(struct inode *);
+int f2fs_getattr(struct vfsmount *, struct dentry *, struct kstat *);
 int f2fs_setattr(struct dentry *, struct iattr *);
 int truncate_hole(struct inode *, pgoff_t, pgoff_t);
 int truncate_data_blocks_range(struct dnode_of_data *, int);

fs/f2fs/file.c

@@ -291,7 +291,7 @@ void f2fs_truncate(struct inode *inode)
 	}
 }
 
-static int f2fs_getattr(struct vfsmount *mnt,
+int f2fs_getattr(struct vfsmount *mnt,
 			 struct dentry *dentry, struct kstat *stat)
 {
 	struct inode *inode = dentry->d_inode;

fs/f2fs/namei.c

@@ -490,6 +490,7 @@ const struct inode_operations f2fs_dir_inode_operations = {
 	.rmdir		= f2fs_rmdir,
 	.mknod		= f2fs_mknod,
 	.rename		= f2fs_rename,
+	.getattr	= f2fs_getattr,
 	.setattr	= f2fs_setattr,
 	.get_acl	= f2fs_get_acl,
 #ifdef CONFIG_F2FS_FS_XATTR
@@ -504,6 +505,7 @@ const struct inode_operations f2fs_symlink_inode_operations = {
 	.readlink       = generic_readlink,
 	.follow_link    = page_follow_link_light,
 	.put_link       = page_put_link,
+	.getattr	= f2fs_getattr,
 	.setattr	= f2fs_setattr,
 #ifdef CONFIG_F2FS_FS_XATTR
 	.setxattr	= generic_setxattr,
@@ -514,6 +516,7 @@ const struct inode_operations f2fs_symlink_inode_operations = {
 };
 
 const struct inode_operations f2fs_special_inode_operations = {
+	.getattr	= f2fs_getattr,
 	.setattr        = f2fs_setattr,
 	.get_acl	= f2fs_get_acl,
 #ifdef CONFIG_F2FS_FS_XATTR