From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from 009.lax.mailroute.net (009.lax.mailroute.net [199.89.1.12]) (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 47EBC212F13; Wed, 2 Oct 2024 18:37:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=199.89.1.12 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727894242; cv=none; b=UsBTNVrRCqbfPoKQxZKENtpZITu9GBjNLjMAqrmvTR+G4dMGiJJqIqiw0M4xkoInNMb4oEGYKU02sUsRjZigaeDzZ+IoBsGZ3k+2Ulw9AVaXM8HhVnVC2Qsx3H9VslR9mUvHTN0iVslgaTaR17PvvlcXYlnxT7kknsvL2RMpF+U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727894242; c=relaxed/simple; bh=msKaBRcTblAvNH8BTmUzvz0ZQ/WRHuI4LW0WaZWGq5s=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=nhK0D1+ypYPKTtQ/UjOeCHy8EfppAEK2xB5rW597TdaQwFGxy/2yO+bewhz1kZCy0blkOSlXq9oidfVOdpqYvTgR7/9XQoc91n8Czyt3B5VzwcocyKCK23xwxPDlsbIzn+Vd8g8o4nFq9r+fODD8GeRevY+WKNlZXKYX8UUMeS8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=acm.org; spf=pass smtp.mailfrom=acm.org; dkim=pass (2048-bit key) header.d=acm.org header.i=@acm.org header.b=QVx1wWKl; arc=none smtp.client-ip=199.89.1.12 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=acm.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=acm.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=acm.org header.i=@acm.org header.b="QVx1wWKl" Received: from localhost (localhost [127.0.0.1]) by 009.lax.mailroute.net (Postfix) with ESMTP id 4XJk7N5N35zlgMWC; Wed, 2 Oct 2024 18:37:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=acm.org; h= content-transfer-encoding:content-type:content-type:in-reply-to :from:from:content-language:references:subject:subject :user-agent:mime-version:date:date:message-id:received:received; s=mr01; t=1727894234; x=1730486235; bh=gslW6VDOBWjnvqvcaaFUhPE4 6K/gPY6VZ++uzHysEOA=; b=QVx1wWKlxWBzqLs+71Yxrsn7vyqP4TVpyyjoh4o2 62HhZ9fJrKxzYpACINtvKg1BPuy36JCEx6L2R3GgrUAQx4XxWKYqNg0RsUMSC6u6 Aiv/Wrtszkqi7GgdDWtE2cEVHSd8kOc0eNspvNP4435z4urSy/DT3l8U7Afatp4E m6rfDf24S/Nn+qdGk10CG2CQefu9V1C9BnvpwIoryOwRTdwarIgnbGqnx7uSSOf+ 3pRFx59bZ+poAt9n+LpCqnn5BZntK47T33xonOKSr5r48mOBmojUu8q3f6us64Kj 4v1sVhZdMROcTC+UHMX15vGvroOFWLclvDkfowLn9WOudg== X-Virus-Scanned: by MailRoute Received: from 009.lax.mailroute.net ([127.0.0.1]) by localhost (009.lax [127.0.0.1]) (mroute_mailscanner, port 10029) with LMTP id W4xEJA9JNW7E; Wed, 2 Oct 2024 18:37:14 +0000 (UTC) Received: from [100.66.154.22] (unknown [104.135.204.82]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: bvanassche@acm.org) by 009.lax.mailroute.net (Postfix) with ESMTPSA id 4XJk7C5sgTzlgMW9; Wed, 2 Oct 2024 18:37:11 +0000 (UTC) Message-ID: <38daf18f-7637-4c27-9a43-67ad39dc15c0@acm.org> Date: Wed, 2 Oct 2024 11:37:11 -0700 Precedence: bulk X-Mailing-List: io-uring@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v7 1/3] nvme: enable FDP support To: Kanchan Joshi , axboe@kernel.dk, kbusch@kernel.org, hch@lst.de, hare@suse.de, sagi@grimberg.me, martin.petersen@oracle.com, brauner@kernel.org, viro@zeniv.linux.org.uk, jack@suse.cz, jaegeuk@kernel.org, bcrl@kvack.org, dhowells@redhat.com, asml.silence@gmail.com Cc: linux-nvme@lists.infradead.org, linux-fsdevel@vger.kernel.org, io-uring@vger.kernel.org, linux-block@vger.kernel.org, linux-aio@kvack.org, gost.dev@samsung.com, vishak.g@samsung.com, javier.gonz@samsung.com, Hui Qi , Nitesh Shetty References: <20240930181305.17286-1-joshi.k@samsung.com> <20240930181305.17286-2-joshi.k@samsung.com> Content-Language: en-US From: Bart Van Assche In-Reply-To: <20240930181305.17286-2-joshi.k@samsung.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 9/30/24 11:13 AM, Kanchan Joshi wrote: > Flexible Data Placement (FDP), as ratified in TP 4146a, allows the host > to control the placement of logical blocks so as to reduce the SSD WAF. > > Userspace can send the data lifetime information using the write hints. > The SCSI driver (sd) can already pass this information to the SCSI > devices. This patch does the same for NVMe. > > Fetch the placement-identifiers if the device supports FDP. > The incoming write-hint is mapped to a placement-identifier, which in > turn is set in the DSPEC field of the write command. Is the description of this patch correct? The above description suggests that FDP information is similar in nature to SCSI data lifetime information. I don't think that's correct. Thanks, Bart.