Make AF_ALG sendmsg() support MSG_SPLICE_PAGES in the hashing code. This causes pages to be spliced from the source iterator if possible. This allows ->sendpage() to be replaced by something that can handle multiple multipage folios in a single transaction. Signed-off-by: David Howells <dhowells@xxxxxxxxxx> cc: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> cc: "David S. Miller" <davem@xxxxxxxxxxxxx> cc: Eric Dumazet <edumazet@xxxxxxxxxx> cc: Jakub Kicinski <kuba@xxxxxxxxxx> cc: Paolo Abeni <pabeni@xxxxxxxxxx> cc: Jens Axboe <axboe@xxxxxxxxx> cc: Matthew Wilcox <willy@xxxxxxxxxxxxx> cc: linux-crypto@xxxxxxxxxxxxxxx cc: netdev@xxxxxxxxxxxxxxx --- crypto/af_alg.c | 11 +++-- crypto/algif_hash.c | 100 +++++++++++++++++++++++++++----------------- 2 files changed, 70 insertions(+), 41 deletions(-) diff --git a/crypto/af_alg.c b/crypto/af_alg.c index 105afd77a064..1965fc4641ed 100644 --- a/crypto/af_alg.c +++ b/crypto/af_alg.c @@ -542,9 +542,14 @@ void af_alg_free_sg(struct af_alg_sgl *sgl) { int i; - if (sgl->need_unpin) - for (i = 0; i < sgl->sgt.nents; i++) - unpin_user_page(sg_page(&sgl->sgt.sgl[i])); + if (sgl->sgt.sgl) { + if (sgl->need_unpin) + for (i = 0; i < sgl->sgt.nents; i++) + unpin_user_page(sg_page(&sgl->sgt.sgl[i])); + if (sgl->sgt.sgl != sgl->sgl) + kvfree(sgl->sgt.sgl); + sgl->sgt.sgl = NULL; + } } EXPORT_SYMBOL_GPL(af_alg_free_sg); diff --git a/crypto/algif_hash.c b/crypto/algif_hash.c index 16c69c4b9c62..3d96c0e06ca6 100644 --- a/crypto/algif_hash.c +++ b/crypto/algif_hash.c @@ -63,78 +63,102 @@ static void hash_free_result(struct sock *sk, struct hash_ctx *ctx) static int hash_sendmsg(struct socket *sock, struct msghdr *msg, size_t ignored) { - int limit = ALG_MAX_PAGES * PAGE_SIZE; struct sock *sk = sock->sk; struct alg_sock *ask = alg_sk(sk); struct hash_ctx *ctx = ask->private; - long copied = 0; + ssize_t copied = 0; + size_t len, max_pages = ALG_MAX_PAGES, npages; + bool continuing = ctx->more, need_init = false; int err; - if (limit > sk->sk_sndbuf) - limit = sk->sk_sndbuf; + /* Don't limit to ALG_MAX_PAGES if the pages are all already pinned. */ + if (!user_backed_iter(&msg->msg_iter)) + max_pages = INT_MAX; + else + max_pages = min_t(size_t, max_pages, + DIV_ROUND_UP(sk->sk_sndbuf, PAGE_SIZE)); lock_sock(sk); - if (!ctx->more) { + if (!continuing) { if ((msg->msg_flags & MSG_MORE)) hash_free_result(sk, ctx); - - err = crypto_wait_req(crypto_ahash_init(&ctx->req), &ctx->wait); - if (err) - goto unlock; + need_init = true; } ctx->more = false; while (msg_data_left(msg)) { - int len = msg_data_left(msg); - - if (len > limit) - len = limit; - ctx->sgl.sgt.sgl = ctx->sgl.sgl; ctx->sgl.sgt.nents = 0; ctx->sgl.sgt.orig_nents = 0; - len = extract_iter_to_sg(&msg->msg_iter, len, &ctx->sgl.sgt, - ALG_MAX_PAGES, 0); - if (len < 0) { - err = copied ? 0 : len; - goto unlock; + err = -EIO; + npages = iov_iter_npages(&msg->msg_iter, max_pages); + if (npages == 0) + goto unlock_free; + + if (npages > ARRAY_SIZE(ctx->sgl.sgl)) { + err = -ENOMEM; + ctx->sgl.sgt.sgl = + kvmalloc(array_size(npages, sizeof(*ctx->sgl.sgt.sgl)), + GFP_KERNEL); + if (!ctx->sgl.sgt.sgl) + goto unlock_free; } - sg_mark_end(ctx->sgl.sgt.sgl + ctx->sgl.sgt.nents); + sg_init_table(ctx->sgl.sgl, npages); ctx->sgl.need_unpin = iov_iter_extract_will_pin(&msg->msg_iter); - ahash_request_set_crypt(&ctx->req, ctx->sgl.sgt.sgl, NULL, len); + err = extract_iter_to_sg(&msg->msg_iter, LONG_MAX, + &ctx->sgl.sgt, npages, 0); + if (err < 0) + goto unlock_free; + len = err; + sg_mark_end(ctx->sgl.sgt.sgl + ctx->sgl.sgt.nents - 1); - err = crypto_wait_req(crypto_ahash_update(&ctx->req), - &ctx->wait); - af_alg_free_sg(&ctx->sgl); - if (err) { - iov_iter_revert(&msg->msg_iter, len); - goto unlock; + if (!msg_data_left(msg)) { + err = hash_alloc_result(sk, ctx); + if (err) + goto unlock_free; } - copied += len; - } + ahash_request_set_crypt(&ctx->req, ctx->sgl.sgt.sgl, ctx->result, len); - err = 0; + if (!msg_data_left(msg) && !continuing && !(msg->msg_flags & MSG_MORE)) { + err = crypto_ahash_digest(&ctx->req); + } else { + if (need_init) { + err = crypto_wait_req(crypto_ahash_init(&ctx->req), + &ctx->wait); + if (err) + goto unlock_free; + need_init = false; + } + + if (msg_data_left(msg) || (msg->msg_flags & MSG_MORE)) + err = crypto_ahash_update(&ctx->req); + else + err = crypto_ahash_finup(&ctx->req); + continuing = true; + } - ctx->more = msg->msg_flags & MSG_MORE; - if (!ctx->more) { - err = hash_alloc_result(sk, ctx); + err = crypto_wait_req(err, &ctx->wait); if (err) - goto unlock; + goto unlock_free; - ahash_request_set_crypt(&ctx->req, NULL, ctx->result, 0); - err = crypto_wait_req(crypto_ahash_final(&ctx->req), - &ctx->wait); + copied += len; + af_alg_free_sg(&ctx->sgl); } + ctx->more = msg->msg_flags & MSG_MORE; + err = 0; unlock: release_sock(sk); + return copied ?: err; - return err ?: copied; +unlock_free: + af_alg_free_sg(&ctx->sgl); + goto unlock; } static ssize_t hash_sendpage(struct socket *sock, struct page *page,