fs: convert simple fs to new truncate

Convert simple filesystems: ramfs, configfs, sysfs, block_dev to new truncate
sequence.

Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/block_dev.c b/fs/block_dev.c
index d0b37e6..7346c96 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -172,8 +172,9 @@
 	struct file *file = iocb->ki_filp;
 	struct inode *inode = file->f_mapping->host;
 
-	return blockdev_direct_IO_no_locking(rw, iocb, inode, I_BDEV(inode),
-				iov, offset, nr_segs, blkdev_get_blocks, NULL);
+	return blockdev_direct_IO_no_locking_newtrunc(rw, iocb, inode,
+				I_BDEV(inode), iov, offset, nr_segs,
+				blkdev_get_blocks, NULL);
 }
 
 int __sync_blockdev(struct block_device *bdev, int wait)
@@ -309,8 +310,8 @@
 			struct page **pagep, void **fsdata)
 {
 	*pagep = NULL;
-	return block_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
-				blkdev_get_block);
+	return block_write_begin_newtrunc(file, mapping, pos, len, flags,
+				pagep, fsdata, blkdev_get_block);
 }
 
 static int blkdev_write_end(struct file *file, struct address_space *mapping,