Bulk update recommendation

Hi,

I've a collection as

{
"code" : "someCode",
price: 3.14,
volume : 6.28
}

I have more then 10 millions of row in this collection and i need to multiply price and volume fields with a number. Because of the row count i don't prefer to retrieve&update so i need a server side solution.
We have $inc with mongodb but nothing line $multiply, then i created a function as

db.collectionName.find().forEach( function(t) {
var price = t.p * 2;
var volume = t.v * 2;
db.collectionName.update({_id: t._id}, { $set: { p: price, v:volume } });
})

i can execute it from mongo shell and it's ok, but i couldn't find a way to execute it from spring mongo environment, is there a way for that or you have any different ideas for that kind of bulk update?