From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 C0095284B3B; Tue, 17 Feb 2026 20:52:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771361552; cv=none; b=ZBW12SV+8Ahi7CNWAYy+hp0eLhUycvsUDCPFdIRVoJP4hbPydH2RdDfum3GiQcv9e3FpE1l29ggi0O+OfBHqOgcj64F2BHDtY8XBcVEuzwqrXmxiygTCLabuIWJaQPlfL6L5hyXbKFaa2hOSmTNGKGsM4AyGcQxHWZ8bp1VTwA4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771361552; c=relaxed/simple; bh=Hmh1wP07ABTdiUIuorwa0N7R/l2CGVyu15nMW0jc2nQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=an4W5+oD8l5XkD7os9WNabqXlNQ8vE8oB/bqrocPcYyr40+IpBj6vYAyWOeCAgyHe9jr7uXGAc//CFR3ckJzLAAYLYgeunqk9PEzON5CVztw4dzs5hGU3ji6VfWs5Yr+ciKEaJdL1OcHRD3QIISZeBkyEP58F6TCTRABYxERRhM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=faSNrhna; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="faSNrhna" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2EC1EC4CEF7; Tue, 17 Feb 2026 20:52:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1771361552; bh=Hmh1wP07ABTdiUIuorwa0N7R/l2CGVyu15nMW0jc2nQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=faSNrhna4PNMaZEZ+ATYmKe0MdnHQ/GIL46OWbSC+thshBQbjfsypx8/D1hH/Ac4U 95utMlD8AEax6qVsO0yuLqaG164uhEQ0FIuvBQUPfNWc3yuz1VM5yM81ed+YuXqkC2 Chb/0rT8DkK+A/9YlZz2W/9rz7jklIV53TcIZJMI= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, stable@kernel.org, Sungjong Seo , Sunmin Jeong , Yeongjin Gil , Chao Yu , Jaegeuk Kim Subject: [PATCH 6.18 39/43] f2fs: optimize f2fs_overwrite_io() for f2fs_iomap_begin Date: Tue, 17 Feb 2026 21:32:19 +0100 Message-ID: <20260217200007.965789196@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260217200006.470920131@linuxfoundation.org> References: <20260217200006.470920131@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Yeongjin Gil commit d860974a7e38d35e9e2c4dc8a9f4223b38b6ad99 upstream. When overwriting already allocated blocks, f2fs_iomap_begin() calls f2fs_overwrite_io() to check block mappings. However, f2fs_overwrite_io() iterates through all mapped blocks in the range, which can be inefficient for fragmented files with large I/O requests. This patch optimizes f2fs_overwrite_io() by adding a 'check_first' parameter and introducing __f2fs_overwrite_io() helper. When called from f2fs_iomap_begin(), we only check the first mapping to determine if the range is already allocated, which is sufficient for setting map.m_may_create. This optimization significantly reduces the number of f2fs_map_blocks() calls in f2fs_overwrite_io() when called from f2fs_iomap_begin(), especially for fragmented files with large I/O requests. Cc: stable@kernel.org Fixes: 351bc761338d ("f2fs: optimize f2fs DIO overwrites") Reviewed-by: Sungjong Seo Reviewed-by: Sunmin Jeong Signed-off-by: Yeongjin Gil Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Greg Kroah-Hartman --- fs/f2fs/data.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -1799,7 +1799,8 @@ out: return err; } -bool f2fs_overwrite_io(struct inode *inode, loff_t pos, size_t len) +static bool __f2fs_overwrite_io(struct inode *inode, loff_t pos, size_t len, + bool check_first) { struct f2fs_map_blocks map; block_t last_lblk; @@ -1821,10 +1822,17 @@ bool f2fs_overwrite_io(struct inode *ino if (err || map.m_len == 0) return false; map.m_lblk += map.m_len; + if (check_first) + break; } return true; } +bool f2fs_overwrite_io(struct inode *inode, loff_t pos, size_t len) +{ + return __f2fs_overwrite_io(inode, pos, len, false); +} + static int f2fs_xattr_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo) { @@ -4191,7 +4199,7 @@ static int f2fs_iomap_begin(struct inode * f2fs_map_lock and f2fs_balance_fs are not necessary. */ if ((flags & IOMAP_WRITE) && - !f2fs_overwrite_io(inode, offset, length)) + !__f2fs_overwrite_io(inode, offset, length, true)) map.m_may_create = true; err = f2fs_map_blocks(inode, &map, F2FS_GET_BLOCK_DIO);