crypto: omap - Avoid redundant copy when using truncated sg list

omap_crypto_cleanup() currently copies data from sg to orig if either
copy flag is set. However OMAP_CRYPTO_SG_COPIED means that sg refers
to the same pages as orig, truncated to len bytes. There is no need
to copy in this case.

Only copy data if the OMAP_CRYPTO_DATA_COPIED flag is set.

Fixes: 74ed87e7e7f7 ("crypto: omap - add base support library for common ...")
Signed-off-by: Ben Hutchings <ben.hutchings@mind.be>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: omap - Drop obsolete PageSlab check

As it is now legal to call flush_dcache_page on slab pages we
no longer need to do the check in the omap driver. This patch
also uses flush_dcache_page instead of flush_kernel_dcache_page
because the page we're writing to could be anything.

Reported-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: omap-crypto - fix userspace copied buffer access

In case buffers are copied from userspace, directly accessing the page
will most likely fail because it hasn't been mapped into the kernel
memory space. Fix the issue by forcing a kmap / kunmap within the
cleanup functionality.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: omap-crypto - copy the temporary data to output buffer properly

Both source and destination are scatterlists that can contain multiple
entries under the omap crypto cleanup handling. Current code only copies
data from the first source scatterlist entry to the target scatterlist,
potentially omitting any sg entries following the first one. Instead,
implement a new routine that walks through both source and target and
copies the data over once it goes.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

Based on 2 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

crypto: omap-crypto - Verify page zone scatterlists before starting DMA

In certain platforms like DRA7xx having memory > 2GB with LPAE enabled
has a constraint that DMA can be done with the initial 2GB and marks it
as ZONE_DMA. But openssl when used with cryptodev does not make sure that
input buffer is DMA capable. So, adding a check to verify if the input
buffer is capable of DMA.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: omap - add base support library for common routines

This contains the generic APIs for aligning SG buffers.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>