From patchwork Tue Apr 14 05:15:09 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mike Christie X-Patchwork-Id: 11486783 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id EFC5015AB for ; Tue, 14 Apr 2020 05:15:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BE452206E9 for ; Tue, 14 Apr 2020 05:15:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Sz1sWYPt" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2405424AbgDNFPW (ORCPT ); Tue, 14 Apr 2020 01:15:22 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:54903 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1729007AbgDNFPW (ORCPT ); Tue, 14 Apr 2020 01:15:22 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1586841320; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=EkNLNHwZfOUTusQOw40Jzr/je7WbnUGoqzc8vWN5NV8=; b=Sz1sWYPtr61jChyRWPEZ8zf6s2B0XlYuXQfpH5ILpCWdrS/dXyAEIkEIgV2sHkFoRAAWJ7 HeREpPD0uAFpX6ohQdz5g4p4KJOSPVtG1wsKRzT0cHrUs3eGLn53gNsEyuAoE8irGWlDzs haj8+tC1V1IEImxpZMFlvVY430gS4EY= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-127-uFra4obzMfWoRnMeCQY-SA-1; Tue, 14 Apr 2020 01:15:18 -0400 X-MC-Unique: uFra4obzMfWoRnMeCQY-SA-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id E2ED4800D53; Tue, 14 Apr 2020 05:15:16 +0000 (UTC) Received: from rh2.redhat.com (ovpn-112-105.rdu2.redhat.com [10.10.112.105]) by smtp.corp.redhat.com (Postfix) with ESMTP id 07FD41001DDE; Tue, 14 Apr 2020 05:15:15 +0000 (UTC) From: Mike Christie To: jsmart2021@gmail.com, martin.petersen@oracle.com, linux-scsi@vger.kernel.org, target-devel@vger.kernel.org, nab@linux-iscsi.org Subject: [RFC PATCH 0/5] target: add sysfs support Date: Tue, 14 Apr 2020 00:15:09 -0500 Message-Id: <20200414051514.7296-1-mchristi@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Sender: target-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: target-devel@vger.kernel.org The following patches made over Linus's current tree allow lio to export info about structs that the kernel initiates creation of via events like initiator login where there is no user interaction like a mkdir. These patches specificially focus on the I_T_nexus/session but could be used for other objects if we want. Why sysfs when we have configfs? I started with configfs and hit bugs like: commit cc57c07343bd071cdf1915a91a24ab7d40c9b590 Author: Mike Christie Date: Sun Jul 15 18:16:17 2018 -0500 configfs: fix registered group removal but it turns out that bug was not really a bug and was just how configfs was meant to work. It seems it was not meant to be used where the kernel initiates creation of dirs/files as a result of some internal action. It's more geared to the user initiating the creation, and my patch just lead to other bugs and was reverted: commit f19e4ed1e1edbfa3c9ccb9fed17759b7d6db24c6 Author: Al Viro Date: Thu Aug 29 23:13:30 2019 -0400 configfs_register_group() shouldn't be (and isn't) called in rmdirable parts So to export the session info we have debugfs, sysfs, ioctl, netlink, etc. sysfs just seemed like a decent fit since one of the primary users is rtslib and it already has lots of file/dir handling code.