From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 898F42EBB8F; Fri, 14 Nov 2025 06:28:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.133 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763101700; cv=none; b=hzuN8v9qRBD7mEF5C8OUKmgc+VesXFjqfdQWnMJI3uhd6glDE+mJ7kd/6xGHnZdkdeXabJaORw0e2LJjUXULe1E7GsrzQkjbm6cWwD+/Yai6b7YytzQ05KIoSuO7p7+BbzgM1muRSQolcq3ftt1zUvJNLam0rG1eGgEqTeTVwcY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763101700; c=relaxed/simple; bh=lD/9+uNWPu6K1TfeQthGZYDbCyhRE8t+atDRVIiqlik=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=nOtnl2xZC1MD1EVkBll5hTLBe0z/Jk85HDapwy7IMy6TRKe5MAUCxvLKbb4fvfo6SPuDJ7ZQ10IsGggKAqpPlj5lucJJEc94T7Mp8zXED3wX/PGfB2rL9B3IGZIzio8jwTaTY2e4l0Zw+xrddP8wgj2FjVeo3fRn3uCe3b+hCCU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=lst.de; spf=none smtp.mailfrom=bombadil.srs.infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=lvdwxBGD; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=lst.de 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) header.d=infradead.org header.i=@infradead.org header.b="lvdwxBGD" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description; bh=OyHWDNa2hmjqb3t/XSa0N0CzevU47yHuhoZRaZrHJbI=; b=lvdwxBGDWoBYEQ/nfAAHsZNNY3 jY4AuBXCawQXRLOyaPlMI5LLmqU5MwEcZ2iZ9FKSwAjcZvSeq8HDf7miGTfVu3SDlmE19HowAEooB oNIN6RSaqDetRmftM3a51Mon50gkFZRR+jjOxZVWtGybPLh7Cgn7kVh/78ONWKYcTMmd8EjyioHiA MDXNVqyF8gGmOq2yCtBt91NLqS0xqOMOdJRDjWg/WCAK6CtDroR5ESte2n6GSsYq/b+xVQmgh3AbH Fpxd4GxosUUHzQT+imUZ2T5Zizf3+Y/m9uUOogf0ou3jKEHDccejfh+LpgRa+5L8txcZfS/MXTzVI K6sYt+qw==; Received: from 2a02-8389-2341-5b80-d601-7564-c2e0-491c.cable.dynamic.v6.surfer.at ([2a02:8389:2341:5b80:d601:7564:c2e0:491c] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.98.2 #2 (Red Hat Linux)) id 1vJnI8-0000000Bf6h-0FyH; Fri, 14 Nov 2025 06:28:16 +0000 From: Christoph Hellwig To: Christian Brauner Cc: Al Viro , David Sterba , Jan Kara , Mike Marshall , Martin Brandenburg , Carlos Maiolino , Stefan Roesch , Jeff Layton , linux-kernel@vger.kernel.org, linux-btrfs@vger.kernel.org, gfs2@lists.linux.dev, io-uring@vger.kernel.org, devel@lists.orangefs.org, linux-unionfs@vger.kernel.org, linux-mtd@lists.infradead.org, linux-xfs@vger.kernel.org, linux-nfs@vger.kernel.org Subject: [PATCH 12/14] fs: add support for non-blocking timestamp updates Date: Fri, 14 Nov 2025 07:26:15 +0100 Message-ID: <20251114062642.1524837-13-hch@lst.de> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20251114062642.1524837-1-hch@lst.de> References: <20251114062642.1524837-1-hch@lst.de> Precedence: bulk X-Mailing-List: io-uring@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Currently file_update_time_flags unconditionally returns -EAGAIN if any timestamp needs to be updated and IOCB_NOWAIT is passed. This makes non-blocking direct writes impossible on file systems with granular enough timestamps. Add a S_NOWAIT to ask for timestamps to not block, and return -EAGAIN in all methods for now. Signed-off-by: Christoph Hellwig --- fs/btrfs/inode.c | 3 +++ fs/fat/misc.c | 3 +++ fs/gfs2/inode.c | 3 +++ fs/inode.c | 5 ++++- fs/orangefs/inode.c | 3 +++ fs/overlayfs/inode.c | 3 +++ fs/ubifs/file.c | 3 +++ fs/xfs/xfs_iops.c | 3 +++ include/linux/fs.h | 10 ++++++---- 9 files changed, 31 insertions(+), 5 deletions(-) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 6282911e536f..dea798d325d1 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -6302,6 +6302,9 @@ static int btrfs_update_time(struct inode *inode, int flags) if (btrfs_root_readonly(root)) return -EROFS; + if (flags & S_NOWAIT) + return -EAGAIN; + dirty = inode_update_timestamps(inode, flags); return dirty ? btrfs_dirty_inode(BTRFS_I(inode)) : 0; } diff --git a/fs/fat/misc.c b/fs/fat/misc.c index 950da09f0961..5df3193c35f9 100644 --- a/fs/fat/misc.c +++ b/fs/fat/misc.c @@ -346,6 +346,9 @@ int fat_update_time(struct inode *inode, int flags) if (inode->i_ino == MSDOS_ROOT_INO) return 0; + if (flags & S_NOWAIT) + return -EAGAIN; + if (flags & (S_ATIME | S_CTIME | S_MTIME)) { fat_truncate_time(inode, NULL, flags); if (inode->i_sb->s_flags & SB_LAZYTIME) diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c index 601c14a3ac77..0184cb64fe9f 100644 --- a/fs/gfs2/inode.c +++ b/fs/gfs2/inode.c @@ -2234,6 +2234,9 @@ static int gfs2_update_time(struct inode *inode, int flags) struct gfs2_holder *gh; int error; + if (flags & S_NOWAIT) + return -EAGAIN; + gh = gfs2_glock_is_locked_by_me(gl); if (gh && gl->gl_state != LM_ST_EXCLUSIVE) { gfs2_glock_dq(gh); diff --git a/fs/inode.c b/fs/inode.c index 34d572c99313..dc6bb6236361 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -2092,6 +2092,9 @@ EXPORT_SYMBOL(inode_update_timestamps); */ int generic_update_time(struct inode *inode, int flags) { + if (flags & S_NOWAIT) + return -EAGAIN; + flags = inode_update_timestamps(inode, flags); if (flags) mark_inode_dirty_time(inode, flags); @@ -2320,7 +2323,7 @@ static int file_update_time_flags(struct file *file, unsigned int flags) return 0; if (flags & IOCB_NOWAIT) - return -EAGAIN; + sync_mode |= S_NOWAIT; if (mnt_get_write_access_file(file)) return 0; diff --git a/fs/orangefs/inode.c b/fs/orangefs/inode.c index 55f6c8026812..9abd4153c85d 100644 --- a/fs/orangefs/inode.c +++ b/fs/orangefs/inode.c @@ -879,6 +879,9 @@ int orangefs_update_time(struct inode *inode, int flags) gossip_debug(GOSSIP_INODE_DEBUG, "orangefs_update_time: %pU\n", get_khandle_from_ino(inode)); + if (flags & S_NOWAIT) + return -EAGAIN; + flags = inode_update_timestamps(inode, flags); memset(&iattr, 0, sizeof iattr); diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c index e11f310ce092..c132d1f5502b 100644 --- a/fs/overlayfs/inode.c +++ b/fs/overlayfs/inode.c @@ -576,6 +576,9 @@ int ovl_update_time(struct inode *inode, int flags) .dentry = ovl_upperdentry_dereference(OVL_I(inode)), }; + if (flags & S_NOWAIT) + return -EAGAIN; + if (upperpath.dentry) { touch_atime(&upperpath); inode_set_atime_to_ts(inode, diff --git a/fs/ubifs/file.c b/fs/ubifs/file.c index 3e119cb93ea9..1caa2a93eaf5 100644 --- a/fs/ubifs/file.c +++ b/fs/ubifs/file.c @@ -1382,6 +1382,9 @@ int ubifs_update_time(struct inode *inode, int flags) if (!IS_ENABLED(CONFIG_UBIFS_ATIME_SUPPORT)) return generic_update_time(inode, flags); + if (flags & S_NOWAIT) + return -EAGAIN; + err = ubifs_budget_space(c, &req); if (err) return err; diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c index 0ace5f790006..da055dade25f 100644 --- a/fs/xfs/xfs_iops.c +++ b/fs/xfs/xfs_iops.c @@ -1195,6 +1195,9 @@ xfs_vn_update_time( trace_xfs_update_time(ip); + if (flags & S_NOWAIT) + return -EAGAIN; + if (inode->i_sb->s_flags & SB_LAZYTIME) { if (!((flags & S_VERSION) && inode_maybe_inc_iversion(inode, false))) diff --git a/include/linux/fs.h b/include/linux/fs.h index 61051c86dbd2..36592fac1887 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2659,10 +2659,12 @@ static inline void inode_dec_link_count(struct inode *inode) } enum file_time_flags { - S_ATIME = 1, - S_MTIME = 2, - S_CTIME = 4, - S_VERSION = 8, + S_ATIME = 1U << 0, + S_MTIME = 1U << 1, + S_CTIME = 1U << 2, + S_VERSION = 1U << 4, + + S_NOWAIT = 1U << 15, }; extern bool atime_needs_update(const struct path *, struct inode *); -- 2.47.3