Add memcpy_sglist which copies one SG list to another.
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
---
crypto/scatterwalk.c | 27 +++++++++++++++++++++++++++
include/crypto/scatterwalk.h | 3 +++
2 files changed, 30 insertions(+)
diff --git a/crypto/scatterwalk.c b/crypto/scatterwalk.c
index 20a28c6d94da..e57ce08e0d8d 100644
--- a/crypto/scatterwalk.c
+++ b/crypto/scatterwalk.c
@@ -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_src(&swalk, len);
+ scatterwalk_done_dst(&dwalk, len);
+ nbytes -= len;
+ } while (nbytes);
+}
+EXPORT_SYMBOL_GPL(memcpy_sglist);
+
struct scatterlist *scatterwalk_ffwd(struct scatterlist dst[2],
struct scatterlist *src,
unsigned int len)
diff --git a/include/crypto/scatterwalk.h b/include/crypto/scatterwalk.h
index 40c3c629e27f..1201543295f9 100644
--- a/include/crypto/scatterwalk.h
+++ b/include/crypto/scatterwalk.h
@@ -208,6 +208,9 @@ 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,
--
2.39.5
--
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
