[PATCH 08/10] crypto/NX: Add NX GZIP user space API

[Herbert Xu]

On Sun, Dec 15, 2019 at 05:05:19AM -0800, Haren Myneni wrote:
> 
> On power9, userspace can send GZIP compression requests directly to NX
> once kernel establishes NX channel / window. This patch provides GZIP
> engine access to user space via /dev/crypto/nx-gzip device node with
> open, VAS_TX_WIN_OPEN ioctl, mmap and close operations.
> 
> Each window corresponds to file descriptor and application can open
> multiple windows. After the window is opened, mmap() system call to map
> the hardware address of engine's request queue into the application's
> virtual address space.
> 
> Then the application can then submit one or more requests to the the
> engine by using the copy/paste instructions and pasting the CRBs to
> the virtual address (aka paste_address) returned by mmap().
> 
> Signed-off-by: Sukadev Bhattiprolu <sukadev at linux.vnet.ibm.com>
> Signed-off-by: Haren Myneni <haren at us.ibm.com>
> ---
>  drivers/crypto/nx/Makefile            |   2 +-
>  drivers/crypto/nx/nx-842-powernv.h    |   2 +
>  drivers/crypto/nx/nx-commom-powernv.c |  21 ++-
>  drivers/crypto/nx/nx-gzip-powernv.c   | 282 ++++++++++++++++++++++++++++++++++
>  4 files changed, 304 insertions(+), 3 deletions(-)
>  create mode 100644 drivers/crypto/nx/nx-gzip-powernv.c

We already have a kernel compress API which could be exposed
to user-space through af_alg.  If every driver created their
own user-space API it would be unmanageable.

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