From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) (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 59888EC4 for ; Thu, 13 Mar 2025 06:37:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.95.11.211 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741847855; cv=none; b=f6LzDAgFWPIxebadVewBd3YFxEKljFQQjG02stv/6dKT0/OaZiMa8QjaWpTa/Q85qYesTR3KWV9Beoi6mG03csAHQGT1KROhVkdPBFRwZxQqrQY7ami0hdCL+g5L6b094nm1DHN+2FHbmac5dkK7ztMrO3HwWsMIxp5x+y17d7M= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741847855; c=relaxed/simple; bh=z+M7T5+oesBRFEivtacNct45Um0/S+YIRwesyjMdhZ0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=lzYvRloUGWjTHzm5UdZ0qP5JaBLXBOHRIui4y/5xQLQS5vsJr6+fjElOUcNnGYsj0YaNde8JtuhrROGWYRIyCOalazmVR/C7vnwrwZ7AgFltKTnuXSovmMSxBEMIxUVK5UBIvZoTnP/ftJspuoifrd7JZcnSlDVLUeWAyFPU6D4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de; spf=pass smtp.mailfrom=lst.de; arc=none smtp.client-ip=213.95.11.211 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=lst.de Received: by verein.lst.de (Postfix, from userid 2407) id 9503D68C4E; Thu, 13 Mar 2025 07:37:30 +0100 (CET) Date: Thu, 13 Mar 2025 07:37:30 +0100 From: Christoph Hellwig To: Mike Christie Cc: chaitanyak@nvidia.com, kbusch@kernel.org, hch@lst.de, sagi@grimberg.me, joao.m.martins@oracle.com, linux-nvme@lists.infradead.org, kvm@vger.kernel.org, kwankhede@nvidia.com, alex.williamson@redhat.com, mlevitsk@redhat.com Subject: Re: [PATCH RFC 03/11] nvmet: Add nvmet_fabrics_ops flag to indicate SGLs not supported Message-ID: <20250313063730.GC9967@lst.de> References: <20250313052222.178524-1-michael.christie@oracle.com> <20250313052222.178524-4-michael.christie@oracle.com> Precedence: bulk X-Mailing-List: kvm@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: <20250313052222.178524-4-michael.christie@oracle.com> User-Agent: Mutt/1.5.17 (2007-11-01) On Thu, Mar 13, 2025 at 12:18:04AM -0500, Mike Christie wrote: > The nvmet_mdev_pci driver does not initially support SGLs. In some > prelim testing I don't think there will be a perf gain (the virt related > interface may be the major bottleneck so I may not notice) so I wasn't > sure if they will be required/needed. This adds a nvmet_fabrics_ops flag > so we can tell nvmet core to tell the host we do not supports SGLS. I'd prefer to be able to support SGLs if we can, but if not I could live with a flag of some sort.