From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 E3371474267 for ; Tue, 25 Aug 2026 13:21:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787664079; cv=none; b=eiYx2oguqODIs16l2k3IDBEtfutP3Jm8gbB51CB7s6Ys6SU8bJ8XMqpY/gUiT2w/em2Qoh1BPVgr4i9Q1UsviPFazfwPlfwPxyIfNJb9prDHUO5dk5IdpZkeRVz7CLMScJd9InNMyfYOqUsfRqEi3dF3RnCk7Y06XhM6OsXdbxo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787664079; c=relaxed/simple; bh=txJCVMXbXZvWlCXPrv6gBGpM1BgXhBKNdFGr0ZEG6w0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=mNFfSODIXKoyPfcjEWkmEZtsoBtlYh8T3wKZo/fo8iuzjGbobrmPE06pl9BjYoKwiJtiZ6XUMad4djKuSTZDnSlJPmhRdCGyoaoWnWQ2yEf4/SgB73wJxnKMD/t6Ni9lIWu3KfwpYVqvs3N9K1xjmWXbnPBTHjJZ5C9O8MvBUzk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=cJ/7DQUT; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="cJ/7DQUT" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1787664071; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=0CGY+glbrnxXmLvEdK2C6tXXpmZuhxXjkwnlUGFD0SY=; b=cJ/7DQUTYY6NbKub6FJxhrh08oBmx2R8eYdrAEBtFPvANXwzBiXUVU0z19FeTJ/eGGX156 YnlfxJHqxEsC2GHsCqhYGoWf8cNcp0axPQE01JLbzsAltCcVczfNk2fteXZXwnUYr4juNP e2BYETSJaETlLv29uIvkBXId5LPTrA8= Received: from mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-617-vs5-qZasO1i6JqHslCjySQ-1; Tue, 25 Aug 2026 09:21:06 -0400 X-MC-Unique: vs5-qZasO1i6JqHslCjySQ-1 X-Mimecast-MFC-AGG-ID: vs5-qZasO1i6JqHslCjySQ_1787664063 Received: from mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.93]) (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) by mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id C883719792FF; Tue, 25 Aug 2026 13:21:02 +0000 (UTC) Received: from warthog.com (unknown [10.44.32.15]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id EA50818005BA; Tue, 25 Aug 2026 13:20:59 +0000 (UTC) From: David Howells To: Christian Brauner Cc: David Howells , Paulo Alcantara , netfs@lists.linux.dev, linux-afs@lists.infradead.org, linux-cifs@vger.kernel.org, ceph-devel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 2/9] netfs: Fix unbuffered/DIO write partial transfer error return Date: Tue, 25 Aug 2026 14:20:36 +0100 Message-ID: <20260825132045.1000787-3-dhowells@redhat.com> In-Reply-To: <20260825132045.1000787-1-dhowells@redhat.com> References: <20260825132045.1000787-1-dhowells@redhat.com> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 Fix unbuffered/DIO write to return the amount of data transferred in preference to an error if a partial transfer has been achieved, and to prefer an error stashed in the request over the one returned by netfs_unbuffered_write() (likely -EINTR or -ERESTARTSYS). Fixes: a0b4c7a49137e ("netfs: Fix unbuffered/DIO writes to dispatch subrequests in strict sequence") Link: https://sashiko.dev/#/patchset/20260824120224.504575-1-dhowells%40redhat.com Signed-off-by: David Howells cc: Paulo Alcantara cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org --- fs/netfs/direct_write.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) diff --git a/fs/netfs/direct_write.c b/fs/netfs/direct_write.c index b04019097ab8..544a4243fc59 100644 --- a/fs/netfs/direct_write.c +++ b/fs/netfs/direct_write.c @@ -139,13 +139,11 @@ static int netfs_unbuffered_write(struct netfs_io_request *wreq) if (test_bit(NETFS_SREQ_NEED_RETRY, &subreq->flags)) { retry = true; } else if (test_bit(NETFS_SREQ_FAILED, &subreq->flags)) { - ret = subreq->error; - wreq->error = ret; + wreq->error = subreq->error; netfs_see_subrequest(subreq, netfs_sreq_trace_see_failed); subreq = NULL; break; } - ret = 0; if (!retry) { netfs_unbuffered_write_collect(wreq, stream, subreq); @@ -288,11 +286,11 @@ ssize_t netfs_unbuffered_write_iter_locked(struct kiocb *iocb, struct iov_iter * ret = -EIOCBQUEUED; } else { ret = netfs_unbuffered_write(wreq); - if (ret < 0) { - _debug("begin = %zd", ret); - } else { + if (wreq->transferred) { iocb->ki_pos += wreq->transferred; - ret = wreq->transferred ?: wreq->error; + ret = wreq->transferred; + } else if (wreq->error) { + ret = wreq->error; } netfs_put_request(wreq, netfs_rreq_trace_put_complete);