Commit 131bdcec authored by Herbert Xu's avatar Herbert Xu
Browse files

crypto: scatterwalk - Add memcpy_sglist 



Add memcpy_sglist which copies one SG list to another.

Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent 65775cf3

crypto/scatterwalk.c

+27 −0
Original line number Diff line number Diff line
@@ -86,6 +86,33 @@ void memcpy_to_sglist(struct scatterlist *sg, unsigned int start, 
}

EXPORT_SYMBOL_GPL(memcpy_to_sglist);



void memcpy_sglist(struct scatterlist *dst, struct scatterlist *src,

		   unsigned int nbytes)

{

	struct scatter_walk swalk;

	struct scatter_walk dwalk;



	if (unlikely(nbytes == 0)) /* in case sg == NULL */

		return;



	scatterwalk_start(&swalk, src);

	scatterwalk_start(&dwalk, dst);



	do {

		unsigned int slen, dlen;

		unsigned int len;



		slen = scatterwalk_next(&swalk, nbytes);

		dlen = scatterwalk_next(&dwalk, nbytes);

		len = min(slen, dlen);

		memcpy(dwalk.addr, swalk.addr, len);

		scatterwalk_done_dst(&dwalk, len);

		scatterwalk_done_src(&swalk, len);

		nbytes -= len;

	} while (nbytes);

}

EXPORT_SYMBOL_GPL(memcpy_sglist);



struct scatterlist *scatterwalk_ffwd(struct scatterlist dst[2],

				     struct scatterlist *src,

				     unsigned int len)

include/crypto/scatterwalk.h

+3 −0
Original line number Diff line number Diff line
@@ -210,6 +210,9 @@ void memcpy_from_sglist(void *buf, struct scatterlist *sg, 
void memcpy_to_sglist(struct scatterlist *sg, unsigned int start,

		      const void *buf, unsigned int nbytes);



void memcpy_sglist(struct scatterlist *dst, struct scatterlist *src,

		   unsigned int nbytes);



/* In new code, please use memcpy_{from,to}_sglist() directly instead. */

static inline void scatterwalk_map_and_copy(void *buf, struct scatterlist *sg,

					    unsigned int start,