From: "Theodore Y. Ts'o" <tytso@mit.edu>
To: ira.weiny@intel.com
Cc: linux-kernel@vger.kernel.org, Jan Kara <jack@suse.cz>,
"Darrick J. Wong" <darrick.wong@oracle.com>,
Dan Williams <dan.j.williams@intel.com>,
Dave Chinner <david@fromorbit.com>,
Christoph Hellwig <hch@lst.de>, Jeff Moyer <jmoyer@redhat.com>,
linux-ext4@vger.kernel.org, linux-xfs@vger.kernel.org,
linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH RFC 3/8] fs/ext4: Disallow encryption if inode is DAX
Date: Wed, 15 Apr 2020 12:03:07 -0400 [thread overview]
Message-ID: <20200415160307.GJ90651@mit.edu> (raw)
In-Reply-To: <20200414040030.1802884-4-ira.weiny@intel.com>
On Mon, Apr 13, 2020 at 09:00:25PM -0700, ira.weiny@intel.com wrote:
> From: Ira Weiny <ira.weiny@intel.com>
>
> Encryption and DAX are incompatible. Changing the DAX mode due to a
> change in Encryption mode is wrong without a corresponding
> address_space_operations update.
>
> Make the 2 options mutually exclusive by returning an error if DAX was
> set first.
>
> Signed-off-by: Ira Weiny <ira.weiny@intel.com>
The encryption flag is inherited from the containing directory, and
directories can't have the DAX flag set, so anything we do in
ext4_set_context() will be safety belt / sanity checking in nature.
But we *do* need to figure out what we do with mount -o dax=always
when the file system might have encrypted files. My previous comments
about the verity flag and dax flag applies here.
Also note that encrypted files are read/write so we must never allow
the combination of ENCRPYT_FL and DAX_FL. So that may be something
where we should teach __ext4_iget() to check for this, and declare the
file system as corrupted if it sees this combination. (For VERITY_FL
&& DAX_FL that is a combo that we might want to support in the future,
so that's probably a case where arguably, we should just ignore the
DAX_FL for now.)
- Ted
next prev parent reply other threads:[~2020-04-15 16:03 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-04-14 4:00 [PATCH RFC 0/8] Enable ext4 support for per-file/directory DAX operations ira.weiny
2020-04-14 4:00 ` [PATCH RFC 1/8] fs/ext4: Narrow scope of DAX check in setflags ira.weiny
2020-04-15 11:45 ` Jan Kara
2020-04-14 4:00 ` [PATCH RFC 2/8] fs/ext4: Disallow verity if inode is DAX ira.weiny
2020-04-15 11:58 ` Jan Kara
2020-04-15 12:00 ` Jan Kara
2020-04-15 15:55 ` Theodore Y. Ts'o
2020-04-15 19:21 ` Ira Weiny
2020-04-15 19:14 ` Ira Weiny
2020-04-16 1:29 ` Eric Biggers
2020-04-16 3:48 ` Ira Weiny
2020-04-15 20:34 ` Ira Weiny
2020-04-14 4:00 ` [PATCH RFC 3/8] fs/ext4: Disallow encryption " ira.weiny
2020-04-15 12:02 ` Jan Kara
2020-04-15 20:35 ` Ira Weiny
2020-04-15 16:03 ` Theodore Y. Ts'o [this message]
2020-04-15 17:27 ` Dan Williams
2020-04-15 19:54 ` Ira Weiny
2020-04-21 18:41 ` Ira Weiny
2020-04-21 18:56 ` Darrick J. Wong
2020-04-14 4:00 ` [PATCH RFC 4/8] fs/ext4: Introduce DAX inode flag ira.weiny
2020-04-15 12:08 ` Jan Kara
2020-04-15 20:39 ` Ira Weiny
2020-04-16 10:32 ` Jan Kara
2020-04-16 18:01 ` Theodore Y. Ts'o
2020-04-16 16:25 ` Darrick J. Wong
2020-04-16 22:33 ` Ira Weiny
2020-04-16 22:49 ` Darrick J. Wong
2020-04-17 0:37 ` Ira Weiny
2020-04-17 1:57 ` Darrick J. Wong
2020-04-17 2:20 ` Ira Weiny
2020-04-17 6:43 ` Andreas Dilger
2020-04-17 17:19 ` Ira Weiny
2020-04-14 4:00 ` [PATCH RFC 5/8] fs/ext4: Make DAX mount option a tri-state ira.weiny
2020-04-15 12:51 ` Jan Kara
2020-04-14 4:00 ` [PATCH RFC 6/8] fs/ext4: Update ext4_should_use_dax() ira.weiny
2020-04-15 13:58 ` Jan Kara
2020-04-17 17:16 ` Ira Weiny
2020-04-14 4:00 ` [PATCH RFC 7/8] fs/ext4: Only change S_DAX on inode load ira.weiny
2020-04-15 14:03 ` Jan Kara
2020-04-17 17:18 ` Ira Weiny
2020-04-14 4:00 ` [PATCH RFC 8/8] Documentation/dax: Update DAX enablement for ext4 ira.weiny
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=20200415160307.GJ90651@mit.edu \
--to=tytso@mit.edu \
--cc=dan.j.williams@intel.com \
--cc=darrick.wong@oracle.com \
--cc=david@fromorbit.com \
--cc=hch@lst.de \
--cc=ira.weiny@intel.com \
--cc=jack@suse.cz \
--cc=jmoyer@redhat.com \
--cc=linux-ext4@vger.kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-xfs@vger.kernel.org \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.