f2fs_preallocate_blocks 3216 fs/f2fs/f2fs.h int f2fs_preallocate_blocks(struct kiocb *iocb, struct iov_iter *from);
f2fs_preallocate_blocks 3378 fs/f2fs/file.c 		err = f2fs_preallocate_blocks(iocb, from);