{"id":810107,"url":"http://patchwork.ozlabs.org/api/patches/810107/?format=json","web_url":"http://patchwork.ozlabs.org/project/netdev/patch/1504615144-29770-2-git-send-email-gilad@benyossef.com/","project":{"id":7,"url":"http://patchwork.ozlabs.org/api/projects/7/?format=json","name":"Linux network development","link_name":"netdev","list_id":"netdev.vger.kernel.org","list_email":"netdev@vger.kernel.org","web_url":null,"scm_url":null,"webscm_url":null,"list_archive_url":"","list_archive_url_format":"","commit_url_format":""},"msgid":"<1504615144-29770-2-git-send-email-gilad@benyossef.com>","list_archive_url":null,"date":"2017-09-05T12:38:40","name":"[v8,01/20] crypto: change transient busy return code to -EAGAIN","commit_ref":null,"pull_url":null,"state":"not-applicable","archived":true,"hash":"f66d3e4dc4f60a6f43f62b4a21790a08a0f34563","submitter":{"id":11198,"url":"http://patchwork.ozlabs.org/api/people/11198/?format=json","name":"Gilad Ben-Yossef","email":"gilad@benyossef.com"},"delegate":{"id":34,"url":"http://patchwork.ozlabs.org/api/users/34/?format=json","username":"davem","first_name":"David","last_name":"Miller","email":"davem@davemloft.net"},"mbox":"http://patchwork.ozlabs.org/project/netdev/patch/1504615144-29770-2-git-send-email-gilad@benyossef.com/mbox/","series":[{"id":1573,"url":"http://patchwork.ozlabs.org/api/series/1573/?format=json","web_url":"http://patchwork.ozlabs.org/project/netdev/list/?series=1573","date":"2017-09-05T12:38:39","name":"simplify crypto wait for async op","version":8,"mbox":"http://patchwork.ozlabs.org/series/1573/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/810107/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/810107/checks/","tags":{},"related":[],"headers":{"Return-Path":"","X-Original-To":"patchwork-incoming@ozlabs.org","Delivered-To":"patchwork-incoming@ozlabs.org","Authentication-Results":"ozlabs.org;\n\tspf=none (mailfrom) smtp.mailfrom=vger.kernel.org\n\t(client-ip=209.132.180.67; helo=vger.kernel.org;\n\tenvelope-from=netdev-owner@vger.kernel.org;\n\treceiver=)","Received":["from vger.kernel.org (vger.kernel.org [209.132.180.67])\n\tby ozlabs.org (Postfix) with ESMTP id 3xmmWb1T7Wz9sRV\n\tfor ;\n\tTue, 5 Sep 2017 22:39:55 +1000 (AEST)","(majordomo@vger.kernel.org) by vger.kernel.org via listexpand\n\tid S1751498AbdIEMjn (ORCPT );\n\tTue, 5 Sep 2017 08:39:43 -0400","from foss.arm.com ([217.140.101.70]:38928 \"EHLO foss.arm.com\"\n\trhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP\n\tid S1750891AbdIEMjf (ORCPT );\n\tTue, 5 Sep 2017 08:39:35 -0400","from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249])\n\tby usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 880DD15BF;\n\tTue, 5 Sep 2017 05:39:34 -0700 (PDT)","from gby.kfn.arm.com (unknown [10.45.48.140])\n\tby usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id\n\t8809E3F3E1; Tue, 5 Sep 2017 05:39:25 -0700 (PDT)"],"From":"Gilad Ben-Yossef ","To":"Herbert Xu ,\n\t\"David S. Miller\" ,\n\tJonathan Corbet , David Howells ,\n\tTom Lendacky , Gary Hook ,\n\tBoris Brezillon ,\n\tArnaud Ebalard ,\n\tMatthias Brugger ,\n\tAlasdair Kergon ,\n\tMike Snitzer , dm-devel@redhat.com,\n\tShaohua Li , Steve French ,\n\t\"Theodore Y. Ts'o\" , Jaegeuk Kim ,\n\tSteffen Klassert ,\n\tAlexey Kuznetsov ,\n\tHideaki YOSHIFUJI ,\n\tMimi Zohar ,\n\tDmitry Kasatkin ,\n\tJames Morris ,\n\t\"Serge E. Hallyn\" , linux-crypto@vger.kernel.org,\n\tlinux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,\n\tkeyrings@vger.kernel.org, linux-arm-kernel@lists.infradead.org,\n\tlinux-mediatek@lists.infradead.org, linux-raid@vger.kernel.org,\n\tlinux-cifs@vger.kernel.org, samba-technical@lists.samba.org,\n\tlinux-fscrypt@vger.kernel.org, netdev@vger.kernel.org,\n\tlinux-ima-devel@lists.sourceforge.net,\n\tlinux-ima-user@lists.sourceforge.net,\n\tlinux-security-module@vger.kernel.org","Cc":"Ofir Drang ","Subject":"[PATCH v8 01/20] crypto: change transient busy return code to\n\t-EAGAIN","Date":"Tue, 5 Sep 2017 15:38:40 +0300","Message-Id":"<1504615144-29770-2-git-send-email-gilad@benyossef.com>","X-Mailer":"git-send-email 2.1.4","In-Reply-To":"<1504615144-29770-1-git-send-email-gilad@benyossef.com>","References":"<1504615144-29770-1-git-send-email-gilad@benyossef.com>","Sender":"netdev-owner@vger.kernel.org","Precedence":"bulk","List-ID":"","X-Mailing-List":"netdev@vger.kernel.org"},"content":"The crypto API was using the -EBUSY return value to indicate\nboth a hard failure to submit a crypto operation into a\ntransformation provider when the latter was busy and the backlog\nmechanism was not enabled as well as a notification that the\noperation was queued into the backlog when the backlog mechanism\nwas enabled.\n\nHaving the same return code indicate two very different conditions\ndepending on a flag is both error prone and requires extra runtime\ncheck like the following to discern between the cases:\n\n\tif (err == -EINPROGRESS ||\n\t (err == -EBUSY && (ahash_request_flags(req) &\n\t\t\t CRYPTO_TFM_REQ_MAY_BACKLOG)))\n\nThis patch changes the return code used to indicate a crypto op\nfailed due to the transformation provider being transiently busy\nto -EAGAIN.\n\nSigned-off-by: Gilad Ben-Yossef \n---\n crypto/algapi.c | 6 ++++--\n crypto/algif_hash.c | 20 +++++++++++++++++---\n crypto/cryptd.c | 4 +---\n 3 files changed, 22 insertions(+), 8 deletions(-)","diff":"diff --git a/crypto/algapi.c b/crypto/algapi.c\nindex aa699ff..916bee3 100644\n--- a/crypto/algapi.c\n+++ b/crypto/algapi.c\n@@ -897,9 +897,11 @@ int crypto_enqueue_request(struct crypto_queue *queue,\n \tint err = -EINPROGRESS;\n \n \tif (unlikely(queue->qlen >= queue->max_qlen)) {\n-\t\terr = -EBUSY;\n-\t\tif (!(request->flags & CRYPTO_TFM_REQ_MAY_BACKLOG))\n+\t\tif (!(request->flags & CRYPTO_TFM_REQ_MAY_BACKLOG)) {\n+\t\t\terr = -EAGAIN;\n \t\t\tgoto out;\n+\t\t}\n+\t\terr = -EBUSY;\n \t\tif (queue->backlog == &queue->list)\n \t\t\tqueue->backlog = &request->list;\n \t}\ndiff --git a/crypto/algif_hash.c b/crypto/algif_hash.c\nindex 5e92bd2..3b3c154 100644\n--- a/crypto/algif_hash.c\n+++ b/crypto/algif_hash.c\n@@ -39,6 +39,20 @@ struct algif_hash_tfm {\n \tbool has_key;\n };\n \n+/* Previous versions of crypto_* ops used to return -EBUSY\n+ * rather than -EAGAIN to indicate being tied up. The in\n+ * kernel API changed but we don't want to break the user\n+ * space API. As only the hash user interface exposed this\n+ * error ever to the user, do the translation here.\n+ */\n+static inline int crypto_user_err(int err)\n+{\n+\tif (err == -EAGAIN)\n+\t\treturn -EBUSY;\n+\n+\treturn err;\n+}\n+\n static int hash_alloc_result(struct sock *sk, struct hash_ctx *ctx)\n {\n \tunsigned ds;\n@@ -136,7 +150,7 @@ static int hash_sendmsg(struct socket *sock, struct msghdr *msg,\n unlock:\n \trelease_sock(sk);\n \n-\treturn err ?: copied;\n+\treturn err ? crypto_user_err(err) : copied;\n }\n \n static ssize_t hash_sendpage(struct socket *sock, struct page *page,\n@@ -188,7 +202,7 @@ static ssize_t hash_sendpage(struct socket *sock, struct page *page,\n unlock:\n \trelease_sock(sk);\n \n-\treturn err ?: size;\n+\treturn err ? crypto_user_err(err) : size;\n }\n \n static int hash_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,\n@@ -236,7 +250,7 @@ static int hash_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,\n \thash_free_result(sk, ctx);\n \trelease_sock(sk);\n \n-\treturn err ?: len;\n+\treturn err ? crypto_user_err(err) : len;\n }\n \n static int hash_accept(struct socket *sock, struct socket *newsock, int flags,\ndiff --git a/crypto/cryptd.c b/crypto/cryptd.c\nindex 0508c48..d1dbdce 100644\n--- a/crypto/cryptd.c\n+++ b/crypto/cryptd.c\n@@ -137,16 +137,14 @@ static int cryptd_enqueue_request(struct cryptd_queue *queue,\n \tint cpu, err;\n \tstruct cryptd_cpu_queue *cpu_queue;\n \tatomic_t *refcnt;\n-\tbool may_backlog;\n \n \tcpu = get_cpu();\n \tcpu_queue = this_cpu_ptr(queue->cpu_queue);\n \terr = crypto_enqueue_request(&cpu_queue->queue, request);\n \n \trefcnt = crypto_tfm_ctx(request->tfm);\n-\tmay_backlog = request->flags & CRYPTO_TFM_REQ_MAY_BACKLOG;\n \n-\tif (err == -EBUSY && !may_backlog)\n+\tif (err == -EAGAIN)\n \t\tgoto out_put_cpu;\n \n \tqueue_work_on(cpu, kcrypto_wq, &cpu_queue->work);\n","prefixes":["v8","01/20"]}