From patchwork Tue Jul 25 20:57:44 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Logan Gunthorpe X-Patchwork-Id: 9863637 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 5A47C601A1 for ; Tue, 25 Jul 2017 21:02:27 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 437E02868B for ; Tue, 25 Jul 2017 21:02:27 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 3844628700; Tue, 25 Jul 2017 21:02:27 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B1BB82868B for ; Tue, 25 Jul 2017 21:02:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751993AbdGYVCM (ORCPT ); Tue, 25 Jul 2017 17:02:12 -0400 Received: from ale.deltatee.com ([207.54.116.67]:36653 "EHLO ale.deltatee.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751612AbdGYU6H (ORCPT ); Tue, 25 Jul 2017 16:58:07 -0400 Received: from cgy1-donard.priv.deltatee.com ([172.16.1.31]) by ale.deltatee.com with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.84_2) (envelope-from ) id 1da6tp-0006j6-TC; Tue, 25 Jul 2017 14:57:58 -0600 Received: from gunthorp by cgy1-donard.priv.deltatee.com with local (Exim 4.89) (envelope-from ) id 1da6tv-0001Fe-P3; Tue, 25 Jul 2017 14:57:55 -0600 From: Logan Gunthorpe To: linux-ntb@googlegroups.com, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Jon Mason , Dave Jiang , Allen Hubbe , Bjorn Helgaas , Greg Kroah-Hartman , Kurt Schwemmer , Stephen Bates , Serge Semin , Logan Gunthorpe Date: Tue, 25 Jul 2017 14:57:44 -0600 Message-Id: <20170725205753.4735-8-logang@deltatee.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20170725205753.4735-1-logang@deltatee.com> References: <20170725205753.4735-1-logang@deltatee.com> X-SA-Exim-Connect-IP: 172.16.1.31 X-SA-Exim-Rcpt-To: linux-ntb@googlegroups.com, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, jdmason@kudzu.us, dave.jiang@intel.com, Allen.Hubbe@emc.com, bhelgaas@google.com, gregkh@linuxfoundation.org, kurt.schwemmer@microsemi.com, sbates@raithlin.com, fancer.lancer@gmail.com, logang@deltatee.com X-SA-Exim-Mail-From: gunthorp@deltatee.com Subject: [PATCH v3 07/16] ntb: add check and comment for link up to mw_count() and mw_get_align() X-SA-Exim-Version: 4.2.1 (built Mon, 26 Dec 2011 16:24:06 +0000) X-SA-Exim-Scanned: Yes (on ale.deltatee.com) Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Adds a comment and a check to ntb_mw_get_align() so that it always fails if the function is called before the link is up. Also adds a comment to ntb_mw_count() to note that it may return 0 if it is called before the link is up. This is to prevent accidental mis-use in clients that are testing on hardware that this doesn't matter for. Signed-off-by: Logan Gunthorpe --- include/linux/ntb.h | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/include/linux/ntb.h b/include/linux/ntb.h index 609e232c00da..47f2966cfd7f 100644 --- a/include/linux/ntb.h +++ b/include/linux/ntb.h @@ -730,7 +730,8 @@ static inline int ntb_link_disable(struct ntb_dev *ntb) * Hardware and topology may support a different number of memory windows. * Moreover different peer devices can support different number of memory * windows. Simply speaking this method returns the number of possible inbound - * memory windows to share with specified peer device. + * memory windows to share with specified peer device. Note: this may return + * zero if the link is not up yet. * * Return: the number of memory windows. */ @@ -751,7 +752,7 @@ static inline int ntb_mw_count(struct ntb_dev *ntb, int pidx) * Get the alignments of an inbound memory window with specified index. * NULL may be given for any output parameter if the value is not needed. * The alignment and size parameters may be used for allocation of proper - * shared memory. + * shared memory. Note: this must only be called when the link is up. * * Return: Zero on success, otherwise a negative error number. */ @@ -760,6 +761,9 @@ static inline int ntb_mw_get_align(struct ntb_dev *ntb, int pidx, int widx, resource_size_t *size_align, resource_size_t *size_max) { + if (!(ntb_link_is_up(ntb, NULL, NULL) & (1 << pidx))) + return -ENOTCONN; + return ntb->ops->mw_get_align(ntb, pidx, widx, addr_align, size_align, size_max); }