From 66db37391dad834a4f739984eec81af27a68b09c Mon Sep 17 00:00:00 2001 From: Tadeusz Struk Date: Thu, 19 Mar 2015 12:31:30 -0700 Subject: [PATCH] crypto: af_alg - Allow to link sgl Allow to link af_alg sgls. Signed-off-by: Tadeusz Struk Signed-off-by: David S. Miller --- crypto/af_alg.c | 18 +++++++++++++----- include/crypto/if_alg.h | 4 +++- 2 files changed, 16 insertions(+), 6 deletions(-) diff --git a/crypto/af_alg.c b/crypto/af_alg.c index 7f8b7edcadca..26089d182cb7 100644 --- a/crypto/af_alg.c +++ b/crypto/af_alg.c @@ -358,8 +358,8 @@ int af_alg_make_sg(struct af_alg_sgl *sgl, struct iov_iter *iter, int len) npages = (off + n + PAGE_SIZE - 1) >> PAGE_SHIFT; if (WARN_ON(npages == 0)) return -EINVAL; - - sg_init_table(sgl->sg, npages); + /* Add one extra for linking */ + sg_init_table(sgl->sg, npages + 1); for (i = 0, len = n; i < npages; i++) { int plen = min_t(int, len, PAGE_SIZE - off); @@ -369,18 +369,26 @@ int af_alg_make_sg(struct af_alg_sgl *sgl, struct iov_iter *iter, int len) off = 0; len -= plen; } + sg_mark_end(sgl->sg + npages - 1); + sgl->npages = npages; + return n; } EXPORT_SYMBOL_GPL(af_alg_make_sg); +void af_alg_link_sg(struct af_alg_sgl *sgl_prev, struct af_alg_sgl *sgl_new) +{ + sg_unmark_end(sgl_prev->sg + sgl_prev->npages - 1); + sg_chain(sgl_prev->sg, sgl_prev->npages + 1, sgl_new->sg); +} +EXPORT_SYMBOL(af_alg_link_sg); + void af_alg_free_sg(struct af_alg_sgl *sgl) { int i; - i = 0; - do { + for (i = 0; i < sgl->npages; i++) put_page(sgl->pages[i]); - } while (!sg_is_last(sgl->sg + (i++))); } EXPORT_SYMBOL_GPL(af_alg_free_sg); diff --git a/include/crypto/if_alg.h b/include/crypto/if_alg.h index 178525e5f430..018afb264ac2 100644 --- a/include/crypto/if_alg.h +++ b/include/crypto/if_alg.h @@ -58,8 +58,9 @@ struct af_alg_type { }; struct af_alg_sgl { - struct scatterlist sg[ALG_MAX_PAGES]; + struct scatterlist sg[ALG_MAX_PAGES + 1]; struct page *pages[ALG_MAX_PAGES]; + unsigned int npages; }; int af_alg_register_type(const struct af_alg_type *type); @@ -70,6 +71,7 @@ int af_alg_accept(struct sock *sk, struct socket *newsock); int af_alg_make_sg(struct af_alg_sgl *sgl, struct iov_iter *iter, int len); void af_alg_free_sg(struct af_alg_sgl *sgl); +void af_alg_link_sg(struct af_alg_sgl *sgl_prev, struct af_alg_sgl *sgl_new); int af_alg_cmsg_send(struct msghdr *msg, struct af_alg_control *con);