From patchwork Tue Dec 8 07:37:28 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hannes Reinecke X-Patchwork-Id: 7795351 Return-Path: X-Original-To: patchwork-linux-scsi@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 46C3EBEEE5 for ; Tue, 8 Dec 2015 07:38:15 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 559872052C for ; Tue, 8 Dec 2015 07:38:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5A4FE20527 for ; Tue, 8 Dec 2015 07:38:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933216AbbLHHiK (ORCPT ); Tue, 8 Dec 2015 02:38:10 -0500 Received: from mx2.suse.de ([195.135.220.15]:46116 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932809AbbLHHhr (ORCPT ); Tue, 8 Dec 2015 02:37:47 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 033D0AC72; Tue, 8 Dec 2015 07:37:42 +0000 (UTC) From: Hannes Reinecke To: "Martin K. Petersen" Cc: James Bottomley , Christoph Hellwig , Ewan Milne , Bart van Assche , linux-scsi@vger.kernel.org, Hannes Reinecke Subject: [PATCH 08/20] scsi_dh_alua: use unique device id Date: Tue, 8 Dec 2015 08:37:28 +0100 Message-Id: <1449560260-53407-9-git-send-email-hare@suse.de> X-Mailer: git-send-email 1.8.5.6 In-Reply-To: <1449560260-53407-1-git-send-email-hare@suse.de> References: <1449560260-53407-1-git-send-email-hare@suse.de> Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=ham 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 Use scsi_vpd_lun_id() to assign a unique device identification to the alua port group structure. Signed-off-by: Hannes Reinecke --- drivers/scsi/device_handler/scsi_dh_alua.c | 64 ++++++++++++++++++++++++++++-- 1 file changed, 61 insertions(+), 3 deletions(-) diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c index ca6322d..688e0f7 100644 --- a/drivers/scsi/device_handler/scsi_dh_alua.c +++ b/drivers/scsi/device_handler/scsi_dh_alua.c @@ -70,6 +70,8 @@ static DEFINE_SPINLOCK(port_group_lock); struct alua_port_group { struct kref kref; struct list_head node; + unsigned char device_id_str[256]; + int device_id_len; int group_id; int tpgs; int state; @@ -162,6 +164,25 @@ static int submit_stpg(struct scsi_device *sdev, int group_id, ALUA_FAILOVER_RETRIES, NULL, req_flags); } +struct alua_port_group *alua_lookup_pg(char *id_str, size_t id_size, + int group_id) +{ + struct alua_port_group *pg = NULL; + + list_for_each_entry(pg, &port_group_list, node) { + if (pg->group_id != group_id) + continue; + if (pg->device_id_len != id_size) + continue; + if (strncmp(pg->device_id_str, id_str, id_size)) + continue; + kref_get(&pg->kref); + return pg; + } + + return NULL; +} + /* * alua_get_pg - Allocate a new port_group structure * @sdev: scsi device @@ -172,19 +193,37 @@ static int submit_stpg(struct scsi_device *sdev, int group_id, * device. */ struct alua_port_group *alua_get_pg(struct scsi_device *sdev, - int group_id, int tpgs) + int group_id, int tpgs, + char *id_str, size_t id_size) { - struct alua_port_group *pg = NULL; + struct alua_port_group *pg = NULL, *tmp_pg; + + spin_lock(&port_group_lock); + pg = alua_lookup_pg(id_str, id_size, group_id); + spin_unlock(&port_group_lock); + if (pg) + return pg; pg = kzalloc(sizeof(struct alua_port_group), GFP_KERNEL); if (!pg) return NULL; + strncpy(pg->device_id_str, id_str, sizeof(pg->device_id_str)); + + pg->device_id_len = id_size; pg->group_id = group_id; pg->tpgs = tpgs; pg->state = TPGS_STATE_OPTIMIZED; kref_init(&pg->kref); + + /* Re-check list again to catch concurrent updates */ spin_lock(&port_group_lock); + tmp_pg = alua_lookup_pg(id_str, id_size, group_id); + if (tmp_pg) { + spin_unlock(&port_group_lock); + kfree(pg); + return tmp_pg; + } list_add(&pg->node, &port_group_list); spin_unlock(&port_group_lock); @@ -592,6 +631,8 @@ static unsigned alua_stpg(struct scsi_device *sdev, struct alua_port_group *pg) static int alua_initialize(struct scsi_device *sdev, struct alua_dh_data *h) { int err = SCSI_DH_DEV_UNSUPP, tpgs; + char device_id_str[256]; + int device_id_len; tpgs = alua_check_tpgs(sdev); if (tpgs == TPGS_MODE_NONE) @@ -601,7 +642,24 @@ static int alua_initialize(struct scsi_device *sdev, struct alua_dh_data *h) if (err != SCSI_DH_OK) goto out; - h->pg = alua_get_pg(sdev, h->group_id, tpgs); + device_id_len = scsi_vpd_lun_id(sdev, device_id_str, + sizeof(device_id_str)); + if (device_id_len <= 0) { + /* + * Internal error: TPGS supported but no device + * identifcation found. Disable ALUA support. + */ + sdev_printk(KERN_INFO, sdev, + "%s: No device descriptors found\n", + ALUA_DH_NAME); + goto out; + } + sdev_printk(KERN_INFO, sdev, + "%s: device %s port group %02x rel port %02x\n", + ALUA_DH_NAME, device_id_str, h->group_id, h->rel_port); + + h->pg = alua_get_pg(sdev, h->group_id, tpgs, + device_id_str, device_id_len); if (!h->pg) { err = SCSI_DH_NOMEM; goto out;