From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 233C6D531; Fri, 15 May 2026 00:24:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778804675; cv=none; b=pXO0OLETF29GM+uaPNO2aLeepQ0ET86PLttDRY5RMvFK69qVkUNwYNkRUsa39oXR8YNQodlaVQKn/zV6bailH+jIxTWXdrjBq/t25ZvtafDOuNBkLNWHpDvx+B55s1HMlMCfyNXxlPbGnOMWzFTWvhD+8wmfV24ZqeYNoT/niw0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778804675; c=relaxed/simple; bh=k4W7/pJA6lvhQOEmxL4Uw4hNh3lzjA73mTSZz6L891g=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=irTtCEXYDjQXWNt01Fpl1FtjmuFsZUexTiOjhqAVbY4sHtgVHYeAFb0DdCrrAfEJAfsopcFrIDhI7JzZe9Zh0ijT5Ij2zQ9u/QxSzpsh1Q8E9Azva5ep/JcvWuotSt0uh9RdU2Cf6gMEadYJLs2xMM6sHen2kC/VPVJ3dPRGppU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=tD2BIK9V; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="tD2BIK9V" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B4531C2BCB3; Fri, 15 May 2026 00:24:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1778804674; bh=k4W7/pJA6lvhQOEmxL4Uw4hNh3lzjA73mTSZz6L891g=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=tD2BIK9VBTnBncsoHz8hImJBJ3vlvh7QDgIdEffKwFpWh0uZadfLaadKAdX2eqx3j 1O1Q4tGiZOyD91QPUiLS+AJb1VVGvzk4bkrysSZSuu9T6ccr8NM0SN4/pYGMoPJBHu AjE5BAOZuSMbBnRBtJ76U8gESt5i/B8vSKtGQYz4c0pOP4YcY6iFBJOxSIpORWYVMs M88egYe3bRFdeq8/MGmTwPRrsqGlGerf1O8hP7/FhsWbrSLsXRCwbsxnYAHC1uH9Q/ DRVqD9qXy3GZ3FbdGLytphLbGeOSMuoDzi7yZ4mSjK/pWw3PZxhBFqXt+KVXF2IHED 5iWXIx1088evA== Date: Thu, 14 May 2026 20:24:33 -0400 From: Mike Snitzer To: John Garry Cc: hch@lst.de, kbusch@kernel.org, sagi@grimberg.me, axboe@fb.com, martin.petersen@oracle.com, james.bottomley@hansenpartnership.com, hare@suse.com, bmarzins@redhat.com, nilay@linux.ibm.com, jmeneghi@redhat.com, linux-nvme@lists.infradead.org, linux-scsi@vger.kernel.org, michael.christie@oracle.com, dm-devel@lists.linux.dev, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 00/13] libmultipath: a generic multipath lib for block drivers Message-ID: References: <20260428111105.1778008-1-john.g.garry@oracle.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260428111105.1778008-1-john.g.garry@oracle.com> On Tue, Apr 28, 2026 at 11:10:52AM +0000, John Garry wrote: > libmultipath: a generic multipath lib for block drivers > > This series introduces libmultipath. It is essentially a refactoring of > NVME multipath support, so we can have a common library to also support > native SCSI multipath. > > Much of the code is taken directly from the NVMe multipath code. However, > NVMe specifics are removed. A template structure is provided so the driver > may provide callbacks for driver specifics, like ANA support for NVMe. > > Important new structures introduced include: > > - mpath_head > These contain much of the multipath-specific functionality from > nvme_ns_head, including a pointer to the gendisk structure and > a path SRCU-based array. > > - mpath_device > This is the per-path structure, and contains much the same > multipath-specific functionality in nvme_ns > > libmultipath provides functionality for path management, path selection, > data path, and failover handling. > > Since the NVMe driver has some code in the sysfs and ioctl handling > which iterate all multipath NSes, functions like mpath_call_for_device() > are added to do the same per-path iteration. To get upstream this library needs an in-tree consumer. So at the end of the series, it'd makes sense to include the NVMe and/or SCSI changes that uses it. Mike