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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 35D22C77B74 for ; Tue, 11 Apr 2023 07:31:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230158AbjDKHbm (ORCPT ); Tue, 11 Apr 2023 03:31:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50592 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230131AbjDKHbU (ORCPT ); Tue, 11 Apr 2023 03:31:20 -0400 Received: from smtp-out2.suse.de (smtp-out2.suse.de [IPv6:2001:67c:2178:6::1d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BE6B130D3; Tue, 11 Apr 2023 00:31:19 -0700 (PDT) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 593CE1FE00; Tue, 11 Apr 2023 07:31:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1681198278; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=zrKJwUKKQqPwV2GMYE3vvKipc0Y4/zBPoyFnBRMPE5Y=; b=Q7qTB94wj3Gg/3rFS/TyqOMweHV6DVNY8f9a/7PDxK74NEJADGNmvOG3RLGuKJW7mhCP4Y A4szjiTISxfspLyeqN9VAYRSn0ky2pDJIssd5vF9K8TOg9FtGJFQK/r81vIlPBqNs+J/qh jV7EEWs6zdGRtusRQYNwY160B7FVLvE= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1681198278; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=zrKJwUKKQqPwV2GMYE3vvKipc0Y4/zBPoyFnBRMPE5Y=; b=JyQyzgRWSbw63ZHATm4TNpQfkxooqhNaR5VOVlFibWtHFYugP8dOZ85ZUQhu15it8YKX4r vb/3/FkJKatR9/AA== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id F3B2E13638; Tue, 11 Apr 2023 07:31:17 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id 71B0OsUMNWRiZgAAMHmgww (envelope-from ); Tue, 11 Apr 2023 07:31:17 +0000 Message-ID: Date: Tue, 11 Apr 2023 09:31:17 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.9.1 Subject: Re: [PATCH v6 15/18] scsi: target: Allow backends to hook into PR handling Content-Language: en-US To: Mike Christie , bvanassche@acm.org, hch@lst.de, martin.petersen@oracle.com, linux-scsi@vger.kernel.org, james.bottomley@hansenpartnership.com, linux-block@vger.kernel.org, dm-devel@redhat.com, snitzer@kernel.org, axboe@kernel.dk, linux-nvme@lists.infradead.org, chaitanyak@nvidia.com, kbusch@kernel.org, target-devel@vger.kernel.org References: <20230407200551.12660-1-michael.christie@oracle.com> <20230407200551.12660-16-michael.christie@oracle.com> From: Hannes Reinecke In-Reply-To: <20230407200551.12660-16-michael.christie@oracle.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org On 4/7/23 22:05, Mike Christie wrote: > For the cases where you want to export a device to a VM via a single > I_T nexus and want to passthrough the PR handling to the physical/real > device you have to use pscsi or tcmu. Both are good for specific uses > however for the case where you want good performance, and are not using > SCSI devices directly (using DM/MD RAID or multipath devices) then we are > out of luck. > > The following patches allow iblock to mimimally hook into the LIO PR code > and then pass the PR handling to the physical device. Note that like with > the tcmu an pscsi cases it's only supported when you export the device via > one I_T nexus. > > This patch adds the initial LIO callouts. The next patch will modify > iblock. > > Signed-off-by: Mike Christie > Reviewed-by: Christoph Hellwig > --- > drivers/target/target_core_pr.c | 62 +++++++++++++++++++++++++++- > include/target/target_core_backend.h | 4 ++ > 2 files changed, 65 insertions(+), 1 deletion(-) > Reviewed-by: Hannes Reinecke Cheers, Hannes -- Dr. Hannes Reinecke Kernel Storage Architect hare@suse.de +49 911 74053 688 SUSE Software Solutions GmbH, Maxfeldstr. 5, 90409 Nürnberg HRB 36809 (AG Nürnberg), Geschäftsführer: Ivo Totev, Andrew Myers, Andrew McDonald, Martje Boudien Moerman