From: Vivek Goyal <vgoyal@redhat.com>
To: JeffleXu <jefflexu@linux.alibaba.com>
Cc: linux-fsdevel@vger.kernel.org,
virtualization@lists.linux-foundation.org,
Liu Bo <bo.liu@linux.alibaba.com>,
stefanha@redhat.com, miklos@szeredi.hu
Subject: Re: [RFC PATCH 3/3] fuse: add per-file DAX flag
Date: Thu, 15 Jul 2021 21:32:47 -0400 [thread overview]
Message-ID: <YPDhv0JJHqbMCyXD@redhat.com> (raw)
In-Reply-To: <6d956097-47c1-5193-bbaa-faf14f0989ef@linux.alibaba.com>
On Fri, Jul 16, 2021 at 09:18:34AM +0800, JeffleXu wrote:
>
>
> On 7/16/21 8:51 AM, Vivek Goyal wrote:
> > On Fri, Jul 16, 2021 at 08:40:29AM +0800, Liu Bo wrote:
> >> On Thu, Jul 15, 2021 at 05:30:31PM +0800, Jeffle Xu wrote:
> >>> Add one flag for fuse_attr.flags indicating if DAX shall be enabled for
> >>> this file.
> >>>
> >>> When the per-file DAX flag changes for an *opened* file, the state of
> >>> the file won't be updated until this file is closed and reopened later.
> >>>
> >>> Currently it is not implemented yet to change per-file DAX flag inside
> >>> guest kernel, e.g., by chattr(1).
> >>
> >> Thanks for the patch, it looks good to me.
> >>
> >> I think it's a good starting point, what I'd like to discuss here is
> >> whether we're going to let chattr to toggle the dax flag.
> >
> > I have the same question. Why not take chattr approach as taken
> > by ext4/xfs as well.
> >
> > Vivek
>
> Thanks.
>
> We can implement the chattr approach as ext4/xfs do, if we have this use
> scenario. It's an RFC patch, and I want to collect more feedback as soon
> as possible.
I guess chattr approach will allow client (as well as server) to control
which files should be DAX. While this approach allows only server to
specify which files should use DAX. Given currently we let client
control whether to use dax or not (-o dax), it probably will make
sense to use chattr based approach?
I will look at the patches. Do you have a corresponding user space
implementation somewhere so that I can test it?
Vivek
_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
next prev parent reply other threads:[~2021-07-16 1:33 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-15 9:30 [RFC PATCH 0/3] virtiofs,fuse: support per-file DAX Jeffle Xu
2021-07-15 9:30 ` [RFC PATCH 1/3] fuse: add fuse_should_enable_dax() helper Jeffle Xu
2021-07-15 9:30 ` [RFC PATCH 2/3] fuse: Make DAX mount option a tri-state Jeffle Xu
2021-07-15 9:30 ` [RFC PATCH 3/3] fuse: add per-file DAX flag Jeffle Xu
[not found] ` <20210716004028.GA30967@rsjd01523.et2sqa>
2021-07-16 0:51 ` Vivek Goyal
2021-07-16 1:18 ` JeffleXu
2021-07-16 1:32 ` Vivek Goyal [this message]
2021-07-16 1:52 ` [PATCH] virtiofsd: support per-file DAX Jeffle Xu
2021-07-16 1:59 ` [RFC PATCH 3/3] fuse: add per-file DAX flag JeffleXu
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=YPDhv0JJHqbMCyXD@redhat.com \
--to=vgoyal@redhat.com \
--cc=bo.liu@linux.alibaba.com \
--cc=jefflexu@linux.alibaba.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=miklos@szeredi.hu \
--cc=stefanha@redhat.com \
--cc=virtualization@lists.linux-foundation.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 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).