From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C3361C3A589 for ; Thu, 15 Aug 2019 16:03:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A12ED2084D for ; Thu, 15 Aug 2019 16:03:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730531AbfHOQDE (ORCPT ); Thu, 15 Aug 2019 12:03:04 -0400 Received: from ale.deltatee.com ([207.54.116.67]:59254 "EHLO ale.deltatee.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726008AbfHOQDC (ORCPT ); Thu, 15 Aug 2019 12:03:02 -0400 Received: from s0106ac1f6bb1ecac.cg.shawcable.net ([70.73.163.230] helo=[192.168.11.155]) by ale.deltatee.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.89) (envelope-from ) id 1hyIDB-00010b-ON; Thu, 15 Aug 2019 10:02:50 -0600 To: Max Gurtovoy , 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 , Stephen Bates References: <20190801234514.7941-1-logang@deltatee.com> <20190801234514.7941-8-logang@deltatee.com> From: Logan Gunthorpe Message-ID: <90e7402f-bd2b-1e3b-1f15-53eff50a1abd@deltatee.com> Date: Thu, 15 Aug 2019 10:02:47 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 70.73.163.230 X-SA-Exim-Rcpt-To: sbates@raithlin.com, Chaitanya.Kulkarni@wdc.com, axboe@fb.com, kbusch@kernel.org, sagi@grimberg.me, hch@lst.de, linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org, linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org, maxg@mellanox.com X-SA-Exim-Mail-From: logang@deltatee.com Subject: Re: [PATCH v7 07/14] nvmet-passthru: add enable/disable helpers 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 On 2019-08-15 6:20 a.m., Max Gurtovoy wrote: > > On 8/2/2019 2:45 AM, Logan Gunthorpe wrote: >> This patch adds helper functions which are used in the NVMeOF configfs >> when the user is configuring the passthru subsystem. Here we ensure >> that only one subsys is assigned to each nvme_ctrl by using an xarray >> on the cntlid. >> >> [chaitanya.kulkarni@wdc.com: this patch is very roughly based >>   on a similar one by Chaitanya] >> Signed-off-by: Chaitanya Kulkarni >> Signed-off-by: Logan Gunthorpe >> --- >>   drivers/nvme/target/core.c            |  8 +++ >>   drivers/nvme/target/io-cmd-passthru.c | 77 +++++++++++++++++++++++++++ >>   drivers/nvme/target/nvmet.h           | 10 ++++ >>   3 files changed, 95 insertions(+) >> >> diff --git a/drivers/nvme/target/core.c b/drivers/nvme/target/core.c >> index 50c01b2da568..2e75968af7f4 100644 >> --- a/drivers/nvme/target/core.c >> +++ b/drivers/nvme/target/core.c >> @@ -519,6 +519,12 @@ int nvmet_ns_enable(struct nvmet_ns *ns) >>         mutex_lock(&subsys->lock); >>       ret = 0; >> + >> +    if (nvmet_passthru_ctrl(subsys)) { >> +        pr_info("cannot enable both passthru and regular namespaces >> for a single subsystem"); >> +        goto out_unlock; >> +    } >> + >>       if (ns->enabled) >>           goto out_unlock; >>   @@ -1439,6 +1445,8 @@ static void nvmet_subsys_free(struct kref *ref) >>         WARN_ON_ONCE(!list_empty(&subsys->namespaces)); >>   +    nvmet_passthru_subsys_free(subsys); >> + >>       kfree(subsys->subsysnqn); >>       kfree(subsys); >>   } >> diff --git a/drivers/nvme/target/io-cmd-passthru.c >> b/drivers/nvme/target/io-cmd-passthru.c >> index 46c58fec5608..b199785500ad 100644 >> --- a/drivers/nvme/target/io-cmd-passthru.c >> +++ b/drivers/nvme/target/io-cmd-passthru.c >> @@ -11,6 +11,11 @@ >>   #include "../host/nvme.h" >>   #include "nvmet.h" >>   +/* >> + * xarray to maintain one passthru subsystem per nvme controller. >> + */ >> +static DEFINE_XARRAY(passthru_subsystems); >> + >>   static struct workqueue_struct *passthru_wq; >>     int nvmet_passthru_init(void) >> @@ -27,6 +32,78 @@ void nvmet_passthru_destroy(void) >>       destroy_workqueue(passthru_wq); >>   } >>   +int nvmet_passthru_ctrl_enable(struct nvmet_subsys *subsys) >> +{ >> +    struct nvme_ctrl *ctrl; >> +    int ret = -EINVAL; >> +    void *old; >> + >> +    mutex_lock(&subsys->lock); >> +    if (!subsys->passthru_ctrl_path) >> +        goto out_unlock; >> +    if (subsys->passthru_ctrl) >> +        goto out_unlock; >> + >> +    if (subsys->nr_namespaces) { >> +        pr_info("cannot enable both passthru and regular namespaces >> for a single subsystem"); >> +        goto out_unlock; >> +    } >> + >> +    ctrl = nvme_ctrl_get_by_path(subsys->passthru_ctrl_path); >> +    if (IS_ERR(ctrl)) { >> +        ret = PTR_ERR(ctrl); >> +        pr_err("failed to open nvme controller %s\n", >> +               subsys->passthru_ctrl_path); >> + >> +        goto out_unlock; >> +    } >> + >> +    old = xa_cmpxchg(&passthru_subsystems, ctrl->cntlid, NULL, >> +             subsys, GFP_KERNEL); >> +    if (xa_is_err(old)) { >> +        ret = xa_err(old); >> +        goto out_put_ctrl; >> +    } >> + >> +    if (old) >> +        goto out_put_ctrl; >> + >> +    subsys->passthru_ctrl = ctrl; >> +    ret = 0; >> + >> +    goto out_unlock; > > can we re-arrange the code here ? > > it's not so common to see goto in a good flow. > > maybe have 1 good flow the goto's will go bellow it as we usually do in > this subsystem. OK, queued up for v8. Thanks, Logan