[PATCH v3 6/8] fsverity: improve performance by using multibuffer hashing

[Herbert Xu]

On Thu, May 30, 2024 at 11:52:58PM -0700, Eric Biggers wrote:
>
> Looking at it again a bit more closely, both fsverity and dm-verity have
> per-block information that they need to keep track of in the queue in addition
> to the data buffers and hashes: the block number, and in dm-verity's case also a
> bvec_iter pointing to that block.

Again I'm not asking you to make this API asynchronous at all.

I was just commenting on the added complexity in fsverify due to
the use of the linear shash API instead of the page-based ahash API.

This complexity was then compounded by the multi-buffer support.

I think this would look a lot simpler if it moved back to ahash.

The original commit mentioned that ahash was bad for fsverify
because of vmalloc.  But the only use of linear pointers in fsverify
seems to be from kmalloc.  Where is the vmalloc coming from?

Cheers,
-- 
Email: Herbert Xu <herbert at gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
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