Commit e7d5d8a8 authored by Eric Biggers's avatar Eric Biggers Committed by Herbert Xu
Browse files

crypto: s390/aes-gcm - use the new scatterwalk functions 



Use scatterwalk_next() which consolidates scatterwalk_clamp() and
scatterwalk_map().  Use scatterwalk_done_src() and
scatterwalk_done_dst() which consolidate scatterwalk_unmap(),
scatterwalk_advance(), and scatterwalk_done().

Besides the new functions being a bit easier to use, this is necessary
because scatterwalk_done() is planned to be removed.

Reviewed-by: default avatarHarald Freudenberger <freude@linux.ibm.com>
Tested-by: default avatarHarald Freudenberger <freude@linux.ibm.com>
Cc: Holger Dengler <dengler@linux.ibm.com>
Cc: linux-s390@vger.kernel.org
Signed-off-by: default avatarEric Biggers <ebiggers@google.com>
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent 422bf8fc

arch/s390/crypto/aes_s390.c

+13 −20
Original line number Diff line number Diff line
@@ -787,28 +787,21 @@ static void gcm_walk_start(struct gcm_sg_walk *gw, struct scatterlist *sg, 


static inline unsigned int _gcm_sg_clamp_and_map(struct gcm_sg_walk *gw)

{

	struct scatterlist *nextsg;



	gw->walk_bytes = scatterwalk_clamp(&gw->walk, gw->walk_bytes_remain);

	while (!gw->walk_bytes) {

		nextsg = sg_next(gw->walk.sg);

		if (!nextsg)

	if (gw->walk_bytes_remain == 0)

		return 0;

		scatterwalk_start(&gw->walk, nextsg);

		gw->walk_bytes = scatterwalk_clamp(&gw->walk,

						   gw->walk_bytes_remain);

	}

	gw->walk_ptr = scatterwalk_map(&gw->walk);

	gw->walk_ptr = scatterwalk_next(&gw->walk, gw->walk_bytes_remain,

					&gw->walk_bytes);

	return gw->walk_bytes;

}



static inline void _gcm_sg_unmap_and_advance(struct gcm_sg_walk *gw,

					     unsigned int nbytes)

					     unsigned int nbytes, bool out)

{

	gw->walk_bytes_remain -= nbytes;

	scatterwalk_unmap(gw->walk_ptr);

	scatterwalk_advance(&gw->walk, nbytes);

	scatterwalk_done(&gw->walk, 0, gw->walk_bytes_remain);

	if (out)

		scatterwalk_done_dst(&gw->walk, gw->walk_ptr, nbytes);

	else

		scatterwalk_done_src(&gw->walk, gw->walk_ptr, nbytes);

	gw->walk_ptr = NULL;

}
@@ -844,7 +837,7 @@ static int gcm_in_walk_go(struct gcm_sg_walk *gw, unsigned int minbytesneeded) 
		n = min(gw->walk_bytes, AES_BLOCK_SIZE - gw->buf_bytes);

		memcpy(gw->buf + gw->buf_bytes, gw->walk_ptr, n);

		gw->buf_bytes += n;

		_gcm_sg_unmap_and_advance(gw, n);

		_gcm_sg_unmap_and_advance(gw, n, false);

		if (gw->buf_bytes >= minbytesneeded) {

			gw->ptr = gw->buf;

			gw->nbytes = gw->buf_bytes;
@@ -904,7 +897,7 @@ static int gcm_in_walk_done(struct gcm_sg_walk *gw, unsigned int bytesdone) 
		} else

			gw->buf_bytes = 0;

	} else

		_gcm_sg_unmap_and_advance(gw, bytesdone);

		_gcm_sg_unmap_and_advance(gw, bytesdone, false);



	return bytesdone;

}
@@ -922,10 +915,10 @@ static int gcm_out_walk_done(struct gcm_sg_walk *gw, unsigned int bytesdone) 
				return i;

			n = min(gw->walk_bytes, bytesdone - i);

			memcpy(gw->walk_ptr, gw->buf + i, n);

			_gcm_sg_unmap_and_advance(gw, n);

			_gcm_sg_unmap_and_advance(gw, n, true);

		}

	} else

		_gcm_sg_unmap_and_advance(gw, bytesdone);

		_gcm_sg_unmap_and_advance(gw, bytesdone, true);



	return bytesdone;

}