From: Ted Ts'o <tytso@mit.edu>
To: "Darrick J. Wong" <djwong@us.ibm.com>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>,
Sunil Mushran <sunil.mushran@oracle.com>,
Martin K Petersen <martin.petersen@oracle.com>,
Greg Freemyer <greg.freemyer@gmail.com>,
Amir Goldstein <amir73il@gmail.com>,
linux-kernel <linux-kernel@vger.kernel.org>,
Andi Kleen <andi@firstfloor.org>, Mingming Cao <cmm@us.ibm.com>,
Joel Becker <jlbec@evilplan.org>,
linux-fsdevel <linux-fsdevel@vger.kernel.org>,
linux-ext4@vger.kernel.org, Coly Li <colyli@gmail.com>
Subject: Re: [PATCH 10/22] ext4: Verify and calculate checksums for extent tree blocks
Date: Mon, 5 Dec 2011 11:40:15 -0500 [thread overview]
Message-ID: <20111205164015.GD32031@thunk.org> (raw)
In-Reply-To: <20111128232725.19194.12626.stgit@elm3c44.beaverton.ibm.com>
On Mon, Nov 28, 2011 at 03:27:25PM -0800, Darrick J. Wong wrote:
> /*
> + * This is the extent tail on-disk structure.
> + * All other extent structures are 12 bytes long. It turns out that
> + * block_size % 12 >= 4 for all valid block sizes (1k, 2k, 4k).
More generally, block_size % 12 is >= 4 for all powers of 2 greater
than 12 bytes. I'd probably remove (1k, 2k, 4k) because that might
scare people who might say, "hey! I'm using a 16k block size on my
HPC system running on a Power or Itanium box --- am I going to be OK?".
Valid block sizes go up to the page size of the hardware in question...
- Ted
next prev parent reply other threads:[~2011-12-05 16:40 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-11-28 23:26 [PATCH v2.1 00/22] ext4: Add metadata checksumming Darrick J. Wong
2011-11-28 23:26 ` [PATCH 01/22] ext4: Create a new BH_Verified flag to avoid unnecessary metadata validation Darrick J. Wong
2011-11-28 23:26 ` [PATCH 02/22] ext4: Create a rocompat flag for extended metadata checksumming Darrick J. Wong
2011-11-28 23:26 ` [PATCH 03/22] ext4: Record the checksum algorithm in use in the superblock Darrick J. Wong
[not found] ` <E0964BB6-793D-49AF-A2B0-20748C6DAE2B@dilger.ca>
2011-12-07 7:42 ` Darrick J. Wong
2011-11-28 23:26 ` [PATCH 04/22] ext4: Only call out to crc32c if necessary Darrick J. Wong
2011-11-28 23:26 ` [PATCH 05/22] ext4: Calculate and verify superblock checksum Darrick J. Wong
2011-11-28 23:26 ` [PATCH 06/22] ext4: Calculate and verify inode checksums Darrick J. Wong
2011-11-28 23:27 ` [PATCH 07/22] ext4: Create bitmap checksum helper functions Darrick J. Wong
2011-12-05 16:33 ` Ted Ts'o
2011-12-05 20:31 ` Darrick J. Wong
2011-12-05 23:54 ` Darrick J. Wong
2011-12-06 17:19 ` Andreas Dilger
2011-12-06 20:59 ` Darrick J. Wong
2011-11-28 23:27 ` [PATCH 08/22] ext4: Calculate and verify checksums for inode bitmaps Darrick J. Wong
2011-11-28 23:27 ` [PATCH 09/22] ext4: Calculate and verify block bitmap checksum Darrick J. Wong
2011-11-28 23:27 ` [PATCH 10/22] ext4: Verify and calculate checksums for extent tree blocks Darrick J. Wong
2011-12-05 16:40 ` Ted Ts'o [this message]
2011-12-05 19:50 ` Darrick J. Wong
2011-11-28 23:27 ` [PATCH 11/22] ext4: Calculate and verify checksums for htree nodes Darrick J. Wong
2011-11-28 23:27 ` [PATCH 12/22] ext4: Calculate and verify checksums of directory leaf blocks Darrick J. Wong
2011-11-28 23:27 ` [PATCH 13/22] ext4: Calculate and verify checksums of extended attribute blocks Darrick J. Wong
2011-11-28 23:27 ` [PATCH 14/22] ext4: Add new feature to make block group checksums use metadata_csum algorithm Darrick J. Wong
2011-11-28 23:28 ` [PATCH 15/22] ext4: Add checksums to the MMP block Darrick J. Wong
2011-11-28 23:28 ` [PATCH 16/22] jbd2: Update structure definitions and flags to support extended checksumming Darrick J. Wong
2011-11-28 23:28 ` [PATCH 17/22] jbd2: Grab a reference to the crc32c driver only when necessary Darrick J. Wong
2011-11-28 23:28 ` [PATCH 18/22] jbd2: Update structure definitions and flags to support extended checksumming Darrick J. Wong
2011-11-28 23:28 ` [PATCH 19/22] jbd2: Checksum revocation blocks Darrick J. Wong
2011-11-28 23:28 ` [PATCH 20/22] jbd2: Checksum descriptor blocks Darrick J. Wong
2011-11-28 23:28 ` [PATCH 21/22] jbd2: Checksum commit blocks Darrick J. Wong
2011-11-28 23:28 ` [PATCH 22/22] jbd2: Checksum data blocks that are stored in the journal Darrick J. Wong
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20111205164015.GD32031@thunk.org \
--to=tytso@mit.edu \
--cc=adilger.kernel@dilger.ca \
--cc=amir73il@gmail.com \
--cc=andi@firstfloor.org \
--cc=cmm@us.ibm.com \
--cc=colyli@gmail.com \
--cc=djwong@us.ibm.com \
--cc=greg.freemyer@gmail.com \
--cc=jlbec@evilplan.org \
--cc=linux-ext4@vger.kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=martin.petersen@oracle.com \
--cc=sunil.mushran@oracle.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).