[PATCH] rd.c blocksize handling

	Unlike other drivers, rd.c wants block size to be set once an
forever (for everybody else setting block size as high as possible and
letting filesystems change it with set_blocksize() is OK; rd.c treats
invalidate_buffers() as "kill the ramdisk contents".

drivers/block/rd.c

@@ -376,6 +376,7 @@ static int rd_open(struct inode * inode, struct file * filp)
 	if (rd_bdev[unit] == NULL) {
 		rd_bdev[unit] = bdget(kdev_t_to_nr(inode->i_rdev));
 		rd_bdev[unit]->bd_openers++;
+		rd_bdev[unit]->bd_block_size = rd_blocksize;
 		rd_bdev[unit]->bd_inode->i_mapping->a_ops = &ramdisk_aops;
 	}