From patchwork Mon Feb 8 14:30:19 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?b?SsO8cmdlbiBHcm/Dnw==?= X-Patchwork-Id: 8250261 Return-Path: X-Original-To: patchwork-xen-devel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 05AD49F319 for ; Mon, 8 Feb 2016 14:33:18 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 196FB2035B for ; Mon, 8 Feb 2016 14:33:17 +0000 (UTC) Received: from lists.xen.org (lists.xenproject.org [50.57.142.19]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0D3B920145 for ; Mon, 8 Feb 2016 14:33:16 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1aSmpf-0002mM-NF; Mon, 08 Feb 2016 14:30:27 +0000 Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1aSmpd-0002lO-78 for xen-devel@lists.xen.org; Mon, 08 Feb 2016 14:30:25 +0000 Received: from [85.158.137.68] by server-5.bemta-3.messagelabs.com id B9/77-07651-086A8B65; Mon, 08 Feb 2016 14:30:24 +0000 X-Env-Sender: jgross@suse.com X-Msg-Ref: server-14.tower-31.messagelabs.com!1454941823!21026910!1 X-Originating-IP: [195.135.220.15] X-SpamReason: No, hits=0.0 required=7.0 tests= X-StarScan-Received: X-StarScan-Version: 7.35.1; banners=-,-,- X-VirusChecked: Checked Received: (qmail 18833 invoked from network); 8 Feb 2016 14:30:23 -0000 Received: from mx2.suse.de (HELO mx2.suse.de) (195.135.220.15) by server-14.tower-31.messagelabs.com with DHE-RSA-CAMELLIA256-SHA encrypted SMTP; 8 Feb 2016 14:30:23 -0000 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 598C6ACAD; Mon, 8 Feb 2016 14:30:23 +0000 (UTC) From: Juergen Gross To: linux-kernel@vger.kernel.org, xen-devel@lists.xen.org, konrad.wilk@oracle.com, david.vrabel@citrix.com, boris.ostrovsky@oracle.com Date: Mon, 8 Feb 2016 15:30:19 +0100 Message-Id: <1454941819-24513-3-git-send-email-jgross@suse.com> X-Mailer: git-send-email 2.6.2 In-Reply-To: <1454941819-24513-1-git-send-email-jgross@suse.com> References: <1454941819-24513-1-git-send-email-jgross@suse.com> Cc: Juergen Gross , stable@vger.kernel.org Subject: [Xen-devel] [PATCH v2 2/2] xen/scsiback: avoid warnings when adding multiple LUNs to a domain X-BeenThere: xen-devel@lists.xen.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP When adding more than one LUN to a frontend a warning for a failed assignment is issued in dom0 for each already existing LUN. Avoid this warning by checking for a LUN already existing when existence is allowed (scsiback_do_add_lun() called with try == 1). As the LUN existence check is needed now for a third time, factor it out into a function. This in turn leads to a more or less complete rewrite of scsiback_del_translation_entry() which will now return a proper error code in case of failure. Signed-off-by: Juergen Gross Cc: stable@vger.kernel.org Reviewed-by: Boris Ostrovsky --- v2: scsiback_del_translation_entry() returns error code instead of 1 (Boris Ostrovsky) --- drivers/xen/xen-scsiback.c | 70 +++++++++++++++++++++++++++------------------- 1 file changed, 41 insertions(+), 29 deletions(-) diff --git a/drivers/xen/xen-scsiback.c b/drivers/xen/xen-scsiback.c index 51387d7..c46ee18 100644 --- a/drivers/xen/xen-scsiback.c +++ b/drivers/xen/xen-scsiback.c @@ -849,15 +849,31 @@ static int scsiback_map(struct vscsibk_info *info) } /* + Check for a translation entry being present +*/ +static struct v2p_entry *scsiback_chk_translation_entry( + struct vscsibk_info *info, struct ids_tuple *v) +{ + struct list_head *head = &(info->v2p_entry_lists); + struct v2p_entry *entry; + + list_for_each_entry(entry, head, l) + if ((entry->v.chn == v->chn) && + (entry->v.tgt == v->tgt) && + (entry->v.lun == v->lun)) + return entry; + + return NULL; +} + +/* Add a new translation entry */ static int scsiback_add_translation_entry(struct vscsibk_info *info, char *phy, struct ids_tuple *v) { int err = 0; - struct v2p_entry *entry; struct v2p_entry *new; - struct list_head *head = &(info->v2p_entry_lists); unsigned long flags; char *lunp; unsigned long long unpacked_lun; @@ -917,15 +933,10 @@ static int scsiback_add_translation_entry(struct vscsibk_info *info, spin_lock_irqsave(&info->v2p_lock, flags); /* Check double assignment to identical virtual ID */ - list_for_each_entry(entry, head, l) { - if ((entry->v.chn == v->chn) && - (entry->v.tgt == v->tgt) && - (entry->v.lun == v->lun)) { - pr_warn("Virtual ID is already used. Assignment was not performed.\n"); - err = -EEXIST; - goto out; - } - + if (scsiback_chk_translation_entry(info, v)) { + pr_warn("Virtual ID is already used. Assignment was not performed.\n"); + err = -EEXIST; + goto out; } /* Create a new translation entry and add to the list */ @@ -933,7 +944,7 @@ static int scsiback_add_translation_entry(struct vscsibk_info *info, new->v = *v; new->tpg = tpg; new->lun = unpacked_lun; - list_add_tail(&new->l, head); + list_add_tail(&new->l, &info->v2p_entry_lists); out: spin_unlock_irqrestore(&info->v2p_lock, flags); @@ -956,39 +967,40 @@ static void __scsiback_del_translation_entry(struct v2p_entry *entry) } /* - Delete the translation entry specfied + Delete the translation entry specified */ static int scsiback_del_translation_entry(struct vscsibk_info *info, struct ids_tuple *v) { struct v2p_entry *entry; - struct list_head *head = &(info->v2p_entry_lists); unsigned long flags; + int ret = 0; spin_lock_irqsave(&info->v2p_lock, flags); /* Find out the translation entry specified */ - list_for_each_entry(entry, head, l) { - if ((entry->v.chn == v->chn) && - (entry->v.tgt == v->tgt) && - (entry->v.lun == v->lun)) { - goto found; - } - } - - spin_unlock_irqrestore(&info->v2p_lock, flags); - return 1; - -found: - /* Delete the translation entry specfied */ - __scsiback_del_translation_entry(entry); + entry = scsiback_chk_translation_entry(info, v); + if (entry) + __scsiback_del_translation_entry(entry); + else + ret = -ENOENT; spin_unlock_irqrestore(&info->v2p_lock, flags); - return 0; + return ret; } static void scsiback_do_add_lun(struct vscsibk_info *info, const char *state, char *phy, struct ids_tuple *vir, int try) { + struct v2p_entry *entry; + unsigned long flags; + + if (try) { + spin_lock_irqsave(&info->v2p_lock, flags); + entry = scsiback_chk_translation_entry(info, vir); + spin_unlock_irqrestore(&info->v2p_lock, flags); + if (entry) + return; + } if (!scsiback_add_translation_entry(info, phy, vir)) { if (xenbus_printf(XBT_NIL, info->dev->nodename, state, "%d", XenbusStateInitialised)) {