lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20240612021058.GA729527@ceph-admin>
Date: Wed, 12 Jun 2024 10:10:58 +0800
From: Long Li <leo.lilong@...wei.com>
To: John Garry <john.g.garry@...cle.com>, <david@...morbit.com>,
	<djwong@...nel.org>, <hch@....de>, <viro@...iv.linux.org.uk>,
	<brauner@...nel.org>, <jack@...e.cz>, <chandan.babu@...cle.com>,
	<willy@...radead.org>
CC: <axboe@...nel.dk>, <martin.petersen@...cle.com>,
	<linux-kernel@...r.kernel.org>, <linux-fsdevel@...r.kernel.org>,
	<tytso@....edu>, <jbongio@...gle.com>, <ojaswin@...ux.ibm.com>,
	<ritesh.list@...il.com>, <mcgrof@...nel.org>, <p.raghav@...sung.com>,
	<linux-xfs@...r.kernel.org>, <catherine.hoang@...cle.com>
Subject: Re: [PATCH v3 08/21] xfs: Introduce FORCEALIGN inode flag

On Mon, Apr 29, 2024 at 05:47:33PM +0000, John Garry wrote:
> From: "Darrick J. Wong" <djwong@...nel.org>
> 
> Add a new inode flag to require that all file data extent mappings must
> be aligned (both the file offset range and the allocated space itself)
> to the extent size hint.  Having a separate COW extent size hint is no
> longer allowed.
> 
> The goal here is to enable sysadmins and users to mandate that all space
> mappings in a file must have a startoff/blockcount that are aligned to
> (say) a 2MB alignment and that the startblock/blockcount will follow the
> same alignment.
> 
> jpg: Enforce extsize is a power-of-2 and aligned with afgsize + stripe
>      alignment for forcealign
> Signed-off-by: "Darrick J. Wong" <djwong@...nel.org>
> Co-developed-by: John Garry <john.g.garry@...cle.com>
> Signed-off-by: John Garry <john.g.garry@...cle.com>
> ---
>  fs/xfs/libxfs/xfs_format.h    |  6 ++++-
>  fs/xfs/libxfs/xfs_inode_buf.c | 50 +++++++++++++++++++++++++++++++++++
>  fs/xfs/libxfs/xfs_inode_buf.h |  3 +++
>  fs/xfs/libxfs/xfs_sb.c        |  2 ++
>  fs/xfs/xfs_inode.c            | 12 +++++++++
>  fs/xfs/xfs_inode.h            |  2 +-
>  fs/xfs/xfs_ioctl.c            | 34 +++++++++++++++++++++++-
>  fs/xfs/xfs_mount.h            |  2 ++
>  fs/xfs/xfs_super.c            |  4 +++
>  include/uapi/linux/fs.h       |  2 ++
>  10 files changed, 114 insertions(+), 3 deletions(-)
> 
> diff --git a/fs/xfs/libxfs/xfs_format.h b/fs/xfs/libxfs/xfs_format.h
> index 2b2f9050fbfb..4dd295b047f8 100644
> --- a/fs/xfs/libxfs/xfs_format.h
> +++ b/fs/xfs/libxfs/xfs_format.h
> @@ -353,6 +353,7 @@ xfs_sb_has_compat_feature(
>  #define XFS_SB_FEAT_RO_COMPAT_RMAPBT   (1 << 1)		/* reverse map btree */
>  #define XFS_SB_FEAT_RO_COMPAT_REFLINK  (1 << 2)		/* reflinked files */
>  #define XFS_SB_FEAT_RO_COMPAT_INOBTCNT (1 << 3)		/* inobt block counts */
> +#define XFS_SB_FEAT_RO_COMPAT_FORCEALIGN (1 << 30)	/* aligned file data extents */
 
Hi, John

You know I've been using and testing your atomic writes patch series recently,
and I'm particularly interested in the changes to the on-disk format. I noticed
that XFS_SB_FEAT_RO_COMPAT_FORCEALIGN uses bit 30 instead of bit 4, which would
be the next available bit in sequence.

I'm wondering if using bit 30 is just a temporary solution to avoid conflicts, 
and if the plan is to eventually use bits sequentially, for example, using bit 4?
I'm looking forward to your explanation.

Thanks,
Long Li

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ