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 13DED41A8E for ; Tue, 5 Nov 2024 06:56:10 +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=1730789771; cv=none; b=k+bKhV0dHxtqa1za/0fDrRXfI3BQ0jXX/LAF7ESShabF0MwPwRb0fo9gBPqGGE6SIbn7w/Woy8djNHjXEoZ5Qy9uGTTl+gXtbPlB3qgdgQceZil6C7doeSFmAbj56LW2o2HLxgSKchEkQ4DcHFg/d0nxwxRPd8xU1le+BXyGLUc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730789771; c=relaxed/simple; bh=Fo2fibcWfMKMCUazhkZYgaohA7hDQkPM3279WGFliLc=; h=Message-ID:Date:MIME-Version:Cc:Subject:To:References:From: In-Reply-To:Content-Type; b=ACk7mwFn7J1NRcdU7vft6N6QbkzsddZwjn02eRe/D8SJH9UDLJaL/i0FIYHd5XCyy3PmGhVKas12ZG7EeR2adszCBSA9Us+QQViEnD8T9gcFkb04OVzLiK5SXdYfTQH8PJ+dhxTWH2Ma7kkRdVSQvzqQAH93/aaS76cSgv545L0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=kM9Lk7Dh; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="kM9Lk7Dh" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E4D61C4CECF; Tue, 5 Nov 2024 06:56:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1730789770; bh=Fo2fibcWfMKMCUazhkZYgaohA7hDQkPM3279WGFliLc=; h=Date:Cc:Subject:To:References:From:In-Reply-To:From; b=kM9Lk7Dhj3ZoWuqoKi1anVPXa2e0He9hAkpFvwOh69eU1ErvxLGilSSedBlKgGgIw 2CrjdyJK/24JV/atfF3CHvYOOBj5st1/rEo7bkFdXadBok1uUSLzDhTWVaHBgl8/w/ tcQR1jlT9pKlu/yKGaFguZrfmYREeWY2S9DC6q0HcXnSswh0R9hV2S91tq2HRbTBe/ 25eW2EWDtOLyhl3zmWVJ+HY76SJnLk93V/g8lS8m4xss0ZJaZ9sqoZoiiDI0csmPxD gI9Xzqx5rUEWAuM7zq5HJ3fdgb26A8A9bdCSBQXfLYRy4ltAKKRQWg+1+66qcFAX9u aydpS2I3b/bLw== Message-ID: Date: Tue, 5 Nov 2024 14:56:06 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Cc: Chao Yu , Zhiguo Niu , jaegeuk@kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, ke.wang@unisoc.com, Hao_hao.Wang@unisoc.com Subject: Re: [PATCH V2] f2fs: fix to adjust appropriate length for fiemap To: Zhiguo Niu References: <1730685372-2995-1-git-send-email-zhiguo.niu@unisoc.com> <888aaf87-1363-4c1f-bd95-d119c72d7b30@kernel.org> Content-Language: en-US From: Chao Yu In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 2024/11/5 12:02, Zhiguo Niu wrote: > Chao Yu 于2024年11月5日周二 11:15写道： >> >> On 2024/11/4 9:56, Zhiguo Niu wrote: >>> If user give a file size as "length" parameter for fiemap >>> operations, but if this size is non-block size aligned, >>> it will show 2 segments fiemap results even this whole file >>> is contiguous on disk, such as the following results: >>> >>> ./f2fs_io fiemap 0 19034 ylog/analyzer.py >>> Fiemap: offset = 0 len = 19034 >>> logical addr. physical addr. length flags >>> 0 0000000000000000 0000000020baa000 0000000000004000 00001000 >>> 1 0000000000004000 0000000020bae000 0000000000001000 00001001 >>> >>> after this patch: >>> ./f2fs_io fiemap 0 19034 ylog/analyzer.py >>> Fiemap: offset = 0 len = 19034 >>> logical addr. physical addr. length flags >>> 0 0000000000000000 00000000315f3000 0000000000005000 00001001 >> >> Hi Zhiguo, >> >> Any testcase to reproduce this bug? w/o this patch, it looks output >> from fiemap looks fine? >> >> f2fs_io fiemap 0 19034 file >> Fiemap: offset = 0 len = 19034 >> logical addr. physical addr. length flags >> 0 0000000000000000 0000000004401000 0000000000005000 00001001 >> > Hi Chao, > Sorry I didn't write clearly enough about the test case, and i put the > note below the ""Singed-off" tag. > let me describe it again， f2fs_io fiemap has been modified by me for > testing in my local, and the length parameter > is the real file size of the file, not the block numer. because user > also pass the real file size to fiemap ioctl. > so with the new f2fs_io fiemap, a contiguous file on disk may be shown > 2 segments if the length is not block size alinged. > such as: > > ums9632_1h10:/data # ls -l ylog/ap/analyzer.py > -rw-rw-rw- 1 root system 19006 2008-01-01 00:00 ylog/ap/analyzer.py > ums9632_1h10:/data # ./f2fs_io fiemap 0 19006 ylog/ap/analyzer.py > Fiemap: offset = 0 len = 19006 > logical addr. physical addr. length flags > 0 0000000000000000 0000000020baa000 0000000000004000 00001000 > 1 0000000000004000 0000000020bae000 0000000000001000 00001001 > > but if we pass a length that is block size alinged, it will show one > whole segment in fiemap log. > ums9632_1h10:/data # ./f2fs_io fiemap 0 20480 ylog/ap/analyzer.py > Fiemap: offset = 0 len = 20480 > logical addr. physical addr. length flags > 0 0000000000000000 0000000020baa000 0000000000005000 00001001 > Thanks. Oh, I can reproduce it w/ xfs_io, thanks for your explanation. xfs_io file -c "fiemap -v 0 19006" file: EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS 0: [0..31]: 139272..139303 32 0x1000 1: [32..39]: 139304..139311 8 0x1001 xfs_io file -c "fiemap -v 0 20480" file: EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS 0: [0..39]: 139272..139311 40 0x1001 Thanks, >> Thanks, >> >>> >>> Signed-off-by: Zhiguo Niu >>> --- >>> V2: correct commit msg according to Chao's questions >>> f2fs_io has been modified for testing, the length for fiemap is >>> real file size, not block number >>> --- >>> fs/f2fs/data.c | 4 ++-- >>> 1 file changed, 2 insertions(+), 2 deletions(-) >>> >>> diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c >>> index 306b86b0..9fc229d 100644 >>> --- a/fs/f2fs/data.c >>> +++ b/fs/f2fs/data.c >>> @@ -1966,8 +1966,8 @@ int f2fs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, >>> goto out; >>> } >>> >>> - if (bytes_to_blks(inode, len) == 0) >>> - len = blks_to_bytes(inode, 1); >>> + if (len & (blks_to_bytes(inode, 1) - 1)) >>> + len = round_up(len, blks_to_bytes(inode, 1)); >>> >>> start_blk = bytes_to_blks(inode, start); >>> last_blk = bytes_to_blks(inode, start + len - 1); >>