From patchwork Wed Aug 28 21:54:17 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Logan Gunthorpe X-Patchwork-Id: 11119987 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 1D5F31395 for ; Wed, 28 Aug 2019 21:55:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 078DE23403 for ; Wed, 28 Aug 2019 21:55:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727709AbfH1Vzh (ORCPT ); Wed, 28 Aug 2019 17:55:37 -0400 Received: from ale.deltatee.com ([207.54.116.67]:46448 "EHLO ale.deltatee.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727103AbfH1Vyj (ORCPT ); Wed, 28 Aug 2019 17:54:39 -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 1i35tj-00071c-NH; Wed, 28 Aug 2019 15:54:38 -0600 Received: from gunthorp by cgy1-donard.priv.deltatee.com with local (Exim 4.92) (envelope-from ) id 1i35ti-0001Cj-5n; Wed, 28 Aug 2019 15:54:34 -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: Wed, 28 Aug 2019 15:54:17 -0600 Message-Id: <20190828215429.4572-2-logang@deltatee.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190828215429.4572-1-logang@deltatee.com> References: <20190828215429.4572-1-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 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on ale.deltatee.com X-Spam-Level: X-Spam-Status: No, score=-8.7 required=5.0 tests=ALL_TRUSTED,BAYES_00, GREYLIST_ISWHITE,MYRULES_NO_TEXT autolearn=ham autolearn_force=no version=3.4.2 Subject: [PATCH v8 01/13] 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 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 Reviewed-by: Sagi Grimberg --- 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 d3d6b7bd6903..776eff8c5ba7 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -2834,6 +2834,30 @@ 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 2d678fb968c7..42d59445ae6b 100644 --- a/drivers/nvme/host/nvme.h +++ b/drivers/nvme/host/nvme.h @@ -489,6 +489,8 @@ 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) {