Scatterlist CryptoAPI 2.6.11.8 - questions regarding implementation

[Allen Rintoul <ark@xxxxxxxxxxxxxxx>]

hi,

I am a kernel newbie trying to understand the Scatterlist CryptoAPI 
which comes with
the kernel (2.6.11.8) and i ran into some unknowns, can someone
enlighten me on this.

1.Why use scatterlist instead of a virtual address(buffer) and buffer
length?
2.What are the precautions that i should take when the buffer spans
multiple pages?
(should i find the no of pages to which the buffer extends and preapare 
a scatterlist struct for each page)

thanks
allen

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Linux-crypto:  cryptography in and on the Linux system
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