From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out30-101.freemail.mail.aliyun.com (out30-101.freemail.mail.aliyun.com [115.124.30.101]) (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 24F9247C107 for ; Fri, 9 Oct 2026 07:55:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.101 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791532536; cv=none; b=u1X2STkB8muIv1BG9s9zvPSgrja/goiMdnhMSnfirZmuJNCTcYnS2diNx6zLEYrq/+ohZ3MexHlD23gmsvvdVh4fZyenqHxt2daNX778RAM0dWmM3DRSg5nejWvoc1dbmn4i4FTXx2gUSx6RPJsTfKQO3xVhxZi+mP8w18zdiZ4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791532536; c=relaxed/simple; bh=PGnXbkWnqgiSvUPXvLuvw04ujDR77ppnXsgjwMpNud0=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=L0TekX7eIg1m9q0uUh4YYQz5onBXWc2wKAeFhAy3dmLft21GNdo63ZKnIyDSVKUkut5RcsP09TykLuGnG2tSfMMZWtOyfolY6bWt5yK3QI1UFNnwn9l2ly6pUoia/uGZdPVJOtIFW8uY98/sHk4sWjCBtWsYvgoEI8qOEK9O4gU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=RIonWdgz; arc=none smtp.client-ip=115.124.30.101 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="RIonWdgz" DKIM-Signature:v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1791532527; h=From:To:Subject:Date:Message-ID:MIME-Version; bh=FlL+KZiK40wut8JLPaAVO6fRQ3vm2gUy0mBBVHvZQDc=; b=RIonWdgzNnGUTAUOaPey1pD6G9B9zBKy33lXQwoVRds2JWM3KALQuqsXhhuL7sF3AxTizETm0mn3CcIR+PslzVcGlNcBGdjIdfbPVA9alNW6+vf2dO93In0iX7qd6NiS+PlA6vos34keXhdzwrGB6JSoZjPmZbs4C5I6Tuv8YLE= X-Alimail-AntiSpam:AC=PASS;BC=-1|-1;BR=01201311R711e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=maildocker-contentspam033037033178;MF=libaokun@linux.alibaba.com;NM=1;PH=DS;RN=4;SR=0;TI=SMTPD_---0XCSmIly_1791532457; Received: from x31h02109.sqa.na131.tbsite.net(mailfrom:libaokun@linux.alibaba.com fp:SMTPD_---0XCSmIly_1791532457 cluster:ay36) by smtp.aliyun-inc.com; Fri, 09 Oct 2026 15:55:26 +0800 From: Baokun Li To: fuse-devel@lists.linux.dev Cc: bernd@bsbernd.com, miklos@szeredi.hu Subject: [PATCH 0/2] libfuse: add support for FUSE_NOTIFY_RESEND Date: Fri, 9 Oct 2026 15:54:14 +0800 Message-ID: <20261009075417.2521879-1-libaokun@linux.alibaba.com> X-Mailer: git-send-email 2.43.7 Precedence: bulk X-Mailing-List: fuse-devel@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Hi all, The FUSE kernel driver supports re-queuing requests that were already sent to a daemon but never answered, e.g. to recover in-flight requests after a daemon takeover. The kernel side was added in Linux 6.9, protocol 7.40 (FUSE_NOTIFY_RESEND / FUSE_HAS_RESEND), but libfuse has no way to use it yet. Patch 1 adds fuse_lowlevel_notify_resend() to send the notification, exposes kernel support through the new FUSE_CAP_HAS_RESEND capability and adds fuse_req_is_resend() so that file systems can detect resent requests via the FUSE_UNIQUE_RESEND bit in the request ID and handle them idempotently. Patch 2 adds a self-contained regression test: the daemon drops the first GETATTR of a file, triggers a resend and expects the request to come back with FUSE_UNIQUE_RESEND set before answering it. Testing ======= The new test passes on Linux 7.3-rc3 (protocol 7.46). It skips on kernels without FUSE_HAS_RESEND support and over the io-uring transport, which recovers requests on its own. Comments and questions are, as always, welcome. Thanks, Baokun Baokun Li (2): fuse_lowlevel: add support for FUSE_NOTIFY_RESEND test: exercise FUSE_NOTIFY_RESEND ChangeLog.rst | 7 + doc/README.notifications | 2 +- include/fuse_common.h | 13 ++ include/fuse_lowlevel.h | 28 ++++ lib/fuse_cap_names_i.h | 1 + lib/fuse_lowlevel.c | 23 +++ lib/fuse_versionscript | 2 + test/cases/ctests/notify-resend.sh | 18 +++ test/meson.build | 3 + test/test_notify_resend.c | 216 +++++++++++++++++++++++++++++ 10 files changed, 312 insertions(+), 1 deletion(-) create mode 100755 test/cases/ctests/notify-resend.sh create mode 100644 test/test_notify_resend.c base-commit: cb2e761c763559f40e41090aabf008f665f27889 -- 2.43.7