From patchwork Thu Jul 25 17:23:20 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Logan Gunthorpe X-Patchwork-Id: 11059379 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 7398C746 for ; Thu, 25 Jul 2019 17:23:56 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5893F28A0C for ; Thu, 25 Jul 2019 17:23:56 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 4C95F28A20; Thu, 25 Jul 2019 17:23:56 +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=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham 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 E626028A0C for ; Thu, 25 Jul 2019 17:23:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391141AbfGYRXz (ORCPT ); Thu, 25 Jul 2019 13:23:55 -0400 Received: from ale.deltatee.com ([207.54.116.67]:39732 "EHLO ale.deltatee.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2391128AbfGYRXy (ORCPT ); Thu, 25 Jul 2019 13:23:54 -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 4.89) (envelope-from ) id 1hqhSv-0001JE-V9; Thu, 25 Jul 2019 11:23:53 -0600 Received: from gunthorp by cgy1-donard.priv.deltatee.com with local (Exim 4.89) (envelope-from ) id 1hqhSu-0001n5-TK; Thu, 25 Jul 2019 11:23:40 -0600 From: Logan Gunthorpe To: linux-kernel@vger.kernel.org, linux-nvme@lists.infradead.org, linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org Cc: Christoph Hellwig , Sagi Grimberg , Keith Busch , Jens Axboe , Chaitanya Kulkarni , Max Gurtovoy , Stephen Bates , Logan Gunthorpe , Greg Kroah-Hartman , Alexander Viro Date: Thu, 25 Jul 2019 11:23:20 -0600 Message-Id: <20190725172335.6825-2-logang@deltatee.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190725172335.6825-1-logang@deltatee.com> References: <20190725172335.6825-1-logang@deltatee.com> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 172.16.1.31 X-SA-Exim-Rcpt-To: linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org, hch@lst.de, sagi@grimberg.me, kbusch@kernel.org, axboe@fb.com, Chaitanya.Kulkarni@wdc.com, maxg@mellanox.com, sbates@raithlin.com, logang@deltatee.com, gregkh@linuxfoundation.org, viro@zeniv.linux.org.uk X-SA-Exim-Mail-From: gunthorp@deltatee.com Subject: [PATCH v6 01/16] chardev: factor out cdev_lookup() helper X-SA-Exim-Version: 4.2.1 (built Tue, 02 Aug 2016 21:08:31 +0000) X-SA-Exim-Scanned: Yes (on ale.deltatee.com) Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Create a new helper out of the code in chrdev_open() which looks up a struct cdev from a struct inode. This will be necessary to create a cdev_get_by_path() which is similar to blkdev_get_by_path() and is required to allow NVMe-OF passthru to lookup an NVMe controller cdev from a path. Signed-off-by: Logan Gunthorpe Cc: Greg Kroah-Hartman Cc: Alexander Viro --- fs/char_dev.c | 26 +++++++++++++++++++------- 1 file changed, 19 insertions(+), 7 deletions(-) diff --git a/fs/char_dev.c b/fs/char_dev.c index 00dfe17871ac..5cc53bd5f654 100644 --- a/fs/char_dev.c +++ b/fs/char_dev.c @@ -367,12 +367,8 @@ void cdev_put(struct cdev *p) } } -/* - * Called every time a character special file is opened - */ -static int chrdev_open(struct inode *inode, struct file *filp) +static struct cdev *cdev_lookup(struct inode *inode) { - const struct file_operations *fops; struct cdev *p; struct cdev *new = NULL; int ret = 0; @@ -385,7 +381,7 @@ static int chrdev_open(struct inode *inode, struct file *filp) spin_unlock(&cdev_lock); kobj = kobj_lookup(cdev_map, inode->i_rdev, &idx); if (!kobj) - return -ENXIO; + return ERR_PTR(-ENXIO); new = container_of(kobj, struct cdev, kobj); spin_lock(&cdev_lock); /* Check i_cdev again in case somebody beat us to it while @@ -402,7 +398,23 @@ static int chrdev_open(struct inode *inode, struct file *filp) spin_unlock(&cdev_lock); cdev_put(new); if (ret) - return ret; + return ERR_PTR(ret); + + return p; +} + +/* + * Called every time a character special file is opened + */ +static int chrdev_open(struct inode *inode, struct file *filp) +{ + const struct file_operations *fops; + struct cdev *p; + int ret = 0; + + p = cdev_lookup(inode); + if (IS_ERR(p)) + return PTR_ERR(p); ret = -ENXIO; fops = fops_get(p->ops);