From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=198.137.202.133 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793781984; b=vf3uSmITNvF0MkiMpC1saR4ZPmwXzvW2UMuqCLdhbXb900MtuR5MtkoRS3fsgzvSNQsF RGCo8i8yprQgt5iPqZ5BmRQ9TeUMIjlZhfyMkg19OS9cfnd9z7Lz+AQh4+vrmQFPlPxwE vjvLf54qJvueRg+O+ATU81+bvLlb+4yjGMOyp/woF+B0XgQVOtf+s8DQnvwlFrX3/quq5 jPUpRVG3Flad5mqxre4E7VvrhtiiPSrhvqRpkpvPQCSpGMY0GE1/5s2jNqXI04Ng44uTC 6C3DNs9DM4EcRuDT0RNj0TV9xd6+I0foblXhyd5zaSz5E6SjlKX8vc7m5fLhE+tI70A== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793781984; h=DMARC-Filter:DKIM-Signature:Received:Date:From:To:Cc:Subject: Message-ID:References:MIME-Version:Content-Type:Content-Disposition: In-Reply-To:X-SRS-Rewrite; bh=jth1TmyTud5UCEFQTt3Qar2WS3gcX17D6HqaaNvengI=; b=aD4tmHS7vyPGd3CNHicXb5Omckxn0c65g5NZu5xiQ04Cg2nGAbfUjrO1tkgXawXPK6ur eY8LbHOLkpq98caYuuyZ02e178Ha107+wJqtoKlIy7w817vjntc0XQY+5PEQFT4v6I7jx U4tfnQOIVuu7x9cDSnPbOVa4iH0b1+XA/R/9dJiLUCUlXiDzCK45z4JHhyQ0gLd6GdMLs UP7HXwwfNviCrh3K6rfsmn873VMSRYcaXn7fE8OkNrbuBZ+YqE7I7n8hNNlcZ7hm2W89L rO/r7EaLqNMo5s+CKGQH+kXb/K1qHBVb7luSNxl4FQnS5QneX8s/kb9EUmv1/x+vEPg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=infradead.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org; dkim=pass header.d=infradead.org header.i=@infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=vvDpXZaK; arc=none smtp.remote-ip=198.137.202.133 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4ECAD606A326 for ; Wed, 4 Nov 2026 08:46:23 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 4ECAD606A326 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=infradead.org header.i=@infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=vvDpXZaK DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=jth1TmyTud5UCEFQTt3Qar2WS3gcX17D6HqaaNvengI=; b=vvDpXZaKAXLQzmyDQz8RXTCxNT 9RqRM9XELqewVEm0V5hNYiY52DSvtNMUKiwfRQgq2Na+j4RqsE1pLsd2Oe8re7D6817bx38Cg0Hj+ tISzUX3ZQcu5JMY3IbK2julFwyV4pSZUY16WnByzofmAevArJ8F2ExqYYDgjGdxn+qFhpzL2+yk6F KNrrxEiNOgAOM25btqiTYawWGKZq4EDdZeg3qCG7gakr/Z+BeUMlsgD9RUEszhSL+aRRzeXllmTl5 4eHh9wrpFlVLZpHGeRdjCfTLBWL+zDdoZrKCUTDE0RjDpWOHs9zZQYqDIyOk05/gu3jiddMaQkEZP fHk9hp5A==; Received: from hch by bombadil.infradead.org with local (Exim 4.100.1 #2 (Red Hat Linux)) id 1xOWdS-00000004kgK-2Pgr; Wed, 04 Nov 2026 08:46:22 +0000 Date: Wed, 4 Nov 2026 00:46:22 -0800 From: Christoph Hellwig To: Qu Wenruo Cc: Christoph Hellwig , Qu Wenruo , linux-btrfs@vger.kernel.org Subject: Re: [PATCH RFC] btrfs: wait for encoded writes in fast fsync Message-ID: References: <514c3590-27bd-42e0-b248-ec422a58e502@gmx.com> X-Mailing-List: linux-btrfs@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <514c3590-27bd-42e0-b248-ec422a58e502@gmx.com> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html On Wed, Nov 04, 2026 at 06:44:55PM +1030, Qu Wenruo wrote: > > It absolutely does not. fsync/fdatasync covers all data and metadata > > changes. It is a fundamental part of O_DIRECT data integrity > > operations to write back metadata and to flush disk caches. > > Even if there is a direct write in the fly? How would you even detect it, > there is no dirty page cache in the range. In-flight I/O is per definition not captured by fsync. fsync applies to previously completed I/O.