From patchwork Thu Aug 1 23:45:00 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Logan Gunthorpe X-Patchwork-Id: 11071563 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 0F30013AC for ; Thu, 1 Aug 2019 23:46:34 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id F1BA0286FF for ; Thu, 1 Aug 2019 23:46:33 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id E375628710; Thu, 1 Aug 2019 23:46:33 +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 8A5DA286FF for ; Thu, 1 Aug 2019 23:46:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388606AbfHAXpW (ORCPT ); Thu, 1 Aug 2019 19:45:22 -0400 Received: from ale.deltatee.com ([207.54.116.67]:32976 "EHLO ale.deltatee.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388581AbfHAXpV (ORCPT ); Thu, 1 Aug 2019 19:45:21 -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 1htKl2-0002M9-OZ; Thu, 01 Aug 2019 17:45:20 -0600 Received: from gunthorp by cgy1-donard.priv.deltatee.com with local (Exim 4.89) (envelope-from ) id 1htKl1-000253-ED; Thu, 01 Aug 2019 17:45:15 -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 Date: Thu, 1 Aug 2019 17:45:00 -0600 Message-Id: <20190801234514.7941-2-logang@deltatee.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190801234514.7941-1-logang@deltatee.com> References: <20190801234514.7941-1-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 X-SA-Exim-Mail-From: gunthorp@deltatee.com Subject: [PATCH v7 01/14] nvme-core: introduce nvme_ctrl_get_by_path() 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-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP nvme_ctrl_get_by_path() is analagous to blkdev_get_by_path() except it gets a struct nvme_ctrl from the path to its char dev (/dev/nvme0). It makes use of filp_open() to open the file and uses the private data to obtain a pointer to the struct nvme_ctrl. If the fops of the file do not match, -EINVAL is returned. The purpose of this function is to support NVMe-OF target passthru. Signed-off-by: Logan Gunthorpe Reviewed-by: Max Gurtovoy --- drivers/nvme/host/core.c | 24 ++++++++++++++++++++++++ drivers/nvme/host/nvme.h | 2 ++ 2 files changed, 26 insertions(+) diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index e6ee6f2a3da6..f72334f34a30 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -2817,6 +2817,30 @@ static const struct file_operations nvme_dev_fops = { .compat_ioctl = nvme_dev_ioctl, }; +struct nvme_ctrl *nvme_ctrl_get_by_path(const char *path) +{ + struct nvme_ctrl *ctrl; + struct file *f; + + f = filp_open(path, O_RDWR, 0); + if (IS_ERR(f)) + return ERR_CAST(f); + + if (f->f_op != &nvme_dev_fops) { + ctrl = ERR_PTR(-EINVAL); + goto out_close; + } + + ctrl = f->private_data; + nvme_get_ctrl(ctrl); + +out_close: + filp_close(f, NULL); + + return ctrl; +} +EXPORT_SYMBOL_GPL(nvme_ctrl_get_by_path); + static ssize_t nvme_sysfs_reset(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h index ecbd90c31d0d..7e827c9e892c 100644 --- a/drivers/nvme/host/nvme.h +++ b/drivers/nvme/host/nvme.h @@ -484,6 +484,8 @@ int nvme_get_log(struct nvme_ctrl *ctrl, u32 nsid, u8 log_page, u8 lsp, extern const struct attribute_group *nvme_ns_id_attr_groups[]; extern const struct block_device_operations nvme_ns_head_ops; +struct nvme_ctrl *nvme_ctrl_get_by_path(const char *path); + #ifdef CONFIG_NVME_MULTIPATH static inline bool nvme_ctrl_use_ana(struct nvme_ctrl *ctrl) {