From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755878AbaIKNEo (ORCPT ); Thu, 11 Sep 2014 09:04:44 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:52280 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754313AbaIKNEl (ORCPT ); Thu, 11 Sep 2014 09:04:41 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Roland Dreier" , "Steve Wise" Date: Thu, 11 Sep 2014 13:32:13 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 054/131] RDMA/iwcm: Use a default listen backlog if needed In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.249 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.63-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Steve Wise commit 2f0304d21867476394cd51a54e97f7273d112261 upstream. If the user creates a listening cm_id with backlog of 0 the IWCM ends up not allowing any connection requests at all. The correct behavior is for the IWCM to pick a default value if the user backlog parameter is zero. Lustre from version 1.8.8 onward uses a backlog of 0, which breaks iwarp support without this fix. Signed-off-by: Steve Wise Signed-off-by: Roland Dreier [bwh: Backported to 3.2: use register_net_sysctl_table()] Signed-off-by: Ben Hutchings --- drivers/infiniband/core/iwcm.c | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) --- a/drivers/infiniband/core/iwcm.c +++ b/drivers/infiniband/core/iwcm.c @@ -46,6 +46,7 @@ #include #include #include +#include #include #include @@ -65,6 +66,20 @@ struct iwcm_work { struct list_head free_list; }; +static unsigned int default_backlog = 256; + +static struct ctl_table_header *iwcm_ctl_table_hdr; +static struct ctl_table iwcm_ctl_table[] = { + { + .procname = "default_backlog", + .data = &default_backlog, + .maxlen = sizeof(default_backlog), + .mode = 0644, + .proc_handler = proc_dointvec, + }, + { } +}; + /* * The following services provide a mechanism for pre-allocating iwcm_work * elements. The design pre-allocates them based on the cm_id type: @@ -419,6 +434,9 @@ int iw_cm_listen(struct iw_cm_id *cm_id, cm_id_priv = container_of(cm_id, struct iwcm_id_private, id); + if (!backlog) + backlog = default_backlog; + ret = alloc_work_entries(cm_id_priv, backlog); if (ret) return ret; @@ -1014,17 +1032,33 @@ int iw_cm_init_qp_attr(struct iw_cm_id * } EXPORT_SYMBOL(iw_cm_init_qp_attr); +static struct ctl_path iwcm_ctl_path[] = { + { .procname = "net" }, + { .procname = "iw_cm" }, + { } +}; + static int __init iw_cm_init(void) { iwcm_wq = create_singlethread_workqueue("iw_cm_wq"); if (!iwcm_wq) return -ENOMEM; + iwcm_ctl_table_hdr = register_net_sysctl_table(&init_net, + iwcm_ctl_path, + iwcm_ctl_table); + if (!iwcm_ctl_table_hdr) { + pr_err("iw_cm: couldn't register sysctl paths\n"); + destroy_workqueue(iwcm_wq); + return -ENOMEM; + } + return 0; } static void __exit iw_cm_cleanup(void) { + unregister_net_sysctl_table(iwcm_ctl_table_hdr); destroy_workqueue(iwcm_wq); }