LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: "Lukáš Czerner" <lczerner@redhat.com>
To: Beata Michalska <b.michalska@samsung.com>
Cc: Christoph Hellwig <hch@infradead.org>,
	adilger.kernel@dilger.ca, tytso@mit.edu,
	linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org,
	kyungmin.park@samsung.com
Subject: Re: [PATCH v2 0/2] ext4: Add pollable sysfs entry for block threshold events
Date: Wed, 18 Mar 2015 11:12:24 +0100 (CET)	[thread overview]
Message-ID: <alpine.LFD.2.00.1503181059150.23465@localhost.localdomain> (raw)
In-Reply-To: <550945D5.4060805@samsung.com>

On Wed, 18 Mar 2015, Beata Michalska wrote:

> Date: Wed, 18 Mar 2015 10:31:01 +0100
> From: Beata Michalska <b.michalska@samsung.com>
> To: Christoph Hellwig <hch@infradead.org>
> Cc: lczerner@redhat.com, adilger.kernel@dilger.ca, tytso@mit.edu,
>     linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org,
>     kyungmin.park@samsung.com
> Subject: Re: [PATCH v2 0/2] ext4: Add pollable sysfs entry for block threshold
>      events
> 
> On 03/16/2015 02:28 PM, Christoph Hellwig wrote:
> > Between this and the recent tmpfs discussion I really think this
> > needs to be done in a generic way.  Given that the quota noticiations
> > already use netlink general space notifications seem like a very
> > sensible extension for them.
> > 
> 
> First of all, apologies for late response.
> 
> I do agree that having a generic solution is the perfect one
> though non-trivial. If I understood You correctly, You would
> like to have quota being extended to cover the case in subject;
> smth similar to xfs project quota and its pqnoenforce mount
> option, as this would require disabling enforcing both:
> soft and hard limits ?

As Jan already mentioned the problem with quota is that it really
is accounting for used space per user, which is not really ideal for
this scenario. I have not seen the tmpfs discussions so maybe
they have a solution ?

Also, implementing noenforce should should be relatively easy.

> 
> 
> We could also consider going back to already mentioned,
> in another thread, the netlink notification interface proposal,
> though this still leaves the problem on how to setup the thresholds
> (as it covers only the ENOSPC case).

As Ted mentioned in one of his replies, filesystem would have to
support it at some level. Probably setting a value within a
superblock and then check against this value.

The netlink notification interface would then serve only as a mean
to notify the user.

Thanks!
-Lukas

> 
> 
> BR
> Beata
> 
> 

  reply	other threads:[~2015-03-18 10:13 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-03-16 13:25 Beata Michalska
2015-03-16 13:25 ` [PATCH v2 1/2] ext4: Add helper function to mark group as corrupted Beata Michalska
2015-03-16 13:25 ` [PATCH v2 2/2] ext4: Add pollable sysfs entry for block threshold events Beata Michalska
2015-03-16 13:28 ` [PATCH v2 0/2] " Christoph Hellwig
2015-03-18  9:31   ` Beata Michalska
2015-03-18 10:12     ` Lukáš Czerner [this message]
2015-03-18 18:20       ` Christoph Hellwig

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=alpine.LFD.2.00.1503181059150.23465@localhost.localdomain \
    --to=lczerner@redhat.com \
    --cc=adilger.kernel@dilger.ca \
    --cc=b.michalska@samsung.com \
    --cc=hch@infradead.org \
    --cc=kyungmin.park@samsung.com \
    --cc=linux-ext4@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=tytso@mit.edu \
    --subject='Re: [PATCH v2 0/2] ext4: Add pollable sysfs entry for block threshold events' \
    /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

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).