Question about ahash export and import

Hello,

Today, the talitos driver dma maps/unmaps context and keys at every single request.
I'm looking at doing the dma mapping at hash init and doing unmapping at final/finup/digest

However, I'm wondering how to manage hash exports and imports. I was initially thinking about doing a dma_sync_for_cpu() before any export and a dma_sync_for_device() after any export, but that supposes that the dma area is already mapped, which means that we have done the init and not yet done a final/finup/digest.

I'm a bit sceptic when reading the following text in include/crypto/hash.h :

@export: Export partial state of the transformation. This function dumps the
 *	    entire state of the ongoing transformation into a provided block of
 *	    data so it can be @import 'ed back later on. This is useful in case
 *	    you want to save partial result of the transformation after
 *	    processing certain amount of data and reload this partial result
 *	    multiple times later on for multiple re-use


Does it mean that import may be called in lieu of hash init, or is hash init always called before doing an import ?

Thanks
Christophe