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=-4.0 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 AFBBEC433E0 for ; Sat, 25 Jul 2020 10:20:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 86FF5206EB for ; Sat, 25 Jul 2020 10:20:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="spus77cQ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726593AbgGYKUz (ORCPT ); Sat, 25 Jul 2020 06:20:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34602 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726572AbgGYKUy (ORCPT ); Sat, 25 Jul 2020 06:20:54 -0400 Received: from mail-pf1-x442.google.com (mail-pf1-x442.google.com [IPv6:2607:f8b0:4864:20::442]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9E3EAC0619D3; Sat, 25 Jul 2020 03:20:54 -0700 (PDT) Received: by mail-pf1-x442.google.com with SMTP id t11so6577662pfq.11; Sat, 25 Jul 2020 03:20:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=yvszqsmZlg6itxeGw8L/x/wm1qBJqQZweDO1j96IDO0=; b=spus77cQf8R8Ufv34pZOkS6h7F4RUoF76Uz/b4+1iIACduk0vhcWn7Z1GFX+EFkxLR p2CbKkTO2nGKY13+7PRrYsQGa0K1q52eIE++tuolq2MNNnBQy8rI59xZmdFx2mIKvDWW aVV7AKxql0j8x8VJ+13Qy+fsPCM3XchTx52vGETEIr8cqIpnWr3xny6JMQpYkN5Nlqkv Z9jsXtWyQt9PVdpCBWbpJB7n5LEMmyr0RCmu+IWNoNdgIP2JWoGyDtddDx17yNxs/Vpe fzaTmYa0vUODDEeWlFXKB5sx5Rf2ow29Ng2bXLnFMWDukRGjd3zUONvwrsZTzkL6Vbx9 jcGQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=yvszqsmZlg6itxeGw8L/x/wm1qBJqQZweDO1j96IDO0=; b=byRU5bFLONM3jNjn4v0VTY/BD/zqiaDjfekvJqor6AZ159DjWf97jrN+jmfeUbtpau EkXjMtQ+VkZkJLbCB8FxRDt3ZaBUQLjvjjAdIGjmaVLhSXI5DmpB7hZMDk98Py6vTU1b tBzU+DJesqtnOzkTP7Orjzr3OwX0A7GKCGO4SnWNyc+/t8AiAjdGR7V0oH3qMXTqGvcz KND0gDJ2B2StxX4+lx1ZZdwN6gOcnpeVuxplIDamxu/T+Srzr7DcpwIWvqWKE7eWfJxz HNn4rehLpAyXIhy75gGymQpU6Kip6/OeevK5KkbvpItIng0OIWvcQUYUCvi3mywxRDSJ lxfA== X-Gm-Message-State: AOAM533CbKvbA3EDYLPUMwdObZmgcoxiJ0eEeItF08Rtr2nuVBUfdDe/ 6XCIEuZgXT3HdrS4CpXMiYJli9dssH2UdVsEQJ0= X-Google-Smtp-Source: ABdhPJz0X5iLT59t4opLAqzgWSJH6IM58/2aP6ew7FM7GCnar7T5Pa42WdgNvCCTNvTMOgHHnxLcfpLH49dPCOVMUHI= X-Received: by 2002:a63:ce41:: with SMTP id r1mr12254644pgi.203.1595672453929; Sat, 25 Jul 2020 03:20:53 -0700 (PDT) MIME-Version: 1.0 References: <20200724171706.1550403-1-tasleson@redhat.com> <20200724171706.1550403-5-tasleson@redhat.com> In-Reply-To: <20200724171706.1550403-5-tasleson@redhat.com> From: Andy Shevchenko Date: Sat, 25 Jul 2020 13:20:37 +0300 Message-ID: Subject: Re: [v4 04/11] scsi: Add durable_name for dev_printk To: Tony Asleson Cc: linux-block@vger.kernel.org, linux-ide@vger.kernel.org, linux-scsi , Bartlomiej Zolnierkiewicz , Jens Axboe Content-Type: text/plain; charset="UTF-8" Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Fri, Jul 24, 2020 at 8:19 PM Tony Asleson wrote: > > Add the needed functions to fill out the durable_name function > call back for scsi based storage devices. This allows calls > into dev_printk for scsi devices to have a persistent id > associated with them. ... > +int scsi_durable_name(struct scsi_device *sdev, char *buf, size_t len) > +{ > + int vpd_len = 0; What is the purpose of the assignment? > + vpd_len = scsi_vpd_lun_id(sdev, buf, len); > + if (vpd_len > 0 && vpd_len < len) > + vpd_len++; > + else > + vpd_len = 0; > + > + return vpd_len; int vpd_len; vpd_len = ...(...); if (vpd_len ...) return vpd_len + 1; return 0; > +} ... > }; > > + One blank line is enough. > +int dev_to_scsi_durable_name(const struct device *dev, char *buf, size_t len) > +{ > + struct scsi_device *sd_dev = NULL; Redundant assignment. > + // When we go through dev_printk in the scsi layer, dev is embedded > + // in a struct scsi_device. When we go through the block layer, > + // dev is embedded in struct genhd, thus we need different paths to > + // retrieve the struct scsi_device to call scsi_durable_name. > + if (dev->type == &scsi_dev_type) { > + sd_dev = to_scsi_device(dev); This... > + } else if (dev->parent && dev->parent->type == &scsi_dev_type) { > + sd_dev = to_scsi_device(dev->parent); ...and this along with pieces in scsi_bus_uevent(), scsi_bus_match() are candidates for a good helper (perhaps with utilization of scsi_is_sdev_device(), but maybe not necessary). static struct scsi_device *dev_to_scsi_device(struct device *dev) { return dev->type == &scsi_dev_type ? to_scsi_device(dev) : NULL; } sdev = dev_to_scsi_device(dev); if (!sdev) sdev = dev_to_scsi_device(dev->parent); if (!sdev) return 0; And when introducing a helper change users at the same time. > + } else { > + // We have a pointer to something else, bail > + return 0; > + } > + > + return scsi_durable_name(sd_dev, buf, len); > +} -- With Best Regards, Andy Shevchenko