diff options
| -rw-r--r-- | crypto/scatterwalk.c | 22 | ||||
| -rw-r--r-- | include/crypto/scatterwalk.h | 4 |
2 files changed, 26 insertions, 0 deletions
diff --git a/crypto/scatterwalk.c b/crypto/scatterwalk.c index 3bd749c7bb70..db920b59a6c3 100644 --- a/crypto/scatterwalk.c +++ b/crypto/scatterwalk.c @@ -146,3 +146,25 @@ int scatterwalk_bytes_sglen(struct scatterlist *sg, int num_bytes) return n; } EXPORT_SYMBOL_GPL(scatterwalk_bytes_sglen); + +struct scatterlist *scatterwalk_ffwd(struct scatterlist dst[2], + struct scatterlist *src, + unsigned int len) +{ + for (;;) { + if (!len) + return src; + + if (src->length > len) + break; + + len -= src->length; + src = sg_next(src); + } + + sg_set_page(dst, sg_page(src), src->length - len, src->offset + len); + scatterwalk_crypto_chain(dst, sg_next(src), 0, 2); + + return dst; +} +EXPORT_SYMBOL_GPL(scatterwalk_ffwd); diff --git a/include/crypto/scatterwalk.h b/include/crypto/scatterwalk.h index 20e4226a2e14..96670e7e7c14 100644 --- a/include/crypto/scatterwalk.h +++ b/include/crypto/scatterwalk.h @@ -102,4 +102,8 @@ void scatterwalk_map_and_copy(void *buf, struct scatterlist *sg, int scatterwalk_bytes_sglen(struct scatterlist *sg, int num_bytes); +struct scatterlist *scatterwalk_ffwd(struct scatterlist dst[2], + struct scatterlist *src, + unsigned int len); + #endif /* _CRYPTO_SCATTERWALK_H */ |