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From: Marco Stornelli <marco.stornelli@gmail.com>
To: Tony Luck <tony.luck@intel.com>
Cc: Linux Kernel <linux-kernel@vger.kernel.org>,
	Linux Embedded <linux-embedded@vger.kernel.org>,
	Linux FS Devel <linux-fsdevel@vger.kernel.org>,
	Tim Bird <tim.bird@am.sony.com>
Subject: Re: [PATCH 01/17] pramfs: documentation
Date: Sat, 08 Jan 2011 09:16:37 +0100	[thread overview]
Message-ID: <4D281D65.1070102@gmail.com> (raw)
In-Reply-To: <AANLkTimtvYfHXG=rMLbFLzVaKbfB6nrj_ZE1AH4quRG2@mail.gmail.com>

On 07/01/2011 22:59, Tony Luck wrote:
> On Fri, Jan 7, 2011 at 12:30 PM, Marco Stornelli
> <marco.stornelli@gmail.com> wrote:
>> constraint). About the errors: pramfs does not maintain file data in the
>> page caches for normal file I/O, so no writeback, the read/write
>> operation are done with direct io and they are always sync. The data are
>> write protected in hw when the arch provide this facility (x86 does).
>> Inode contains a checksum and when there are problems they are marked as
>> bad. Superblock contains checksum and there is a redundant superblock.
> 
> But you can still get pramfs inconsistencies if the system crashes at an
> inopportune moment. E.g. when making files you write the new inode to
> pramfs, and then you insert the entry into the directory. A crash between
> these two operations leaves an allocated inode that doesn't appear in
> any directory.  Without a fsck option, it will be hard to see that you have
> this problem, and your only recovery option is to wipe *all* files by making
> a new filesystem.

Is it a problem if you lost some logs? However do you expect that fsck
in this case will drop the inode?

  reply	other threads:[~2011-01-08  8:16 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-01-06 12:01 [PATCH 01/17] pramfs: documentation Marco Stornelli
2011-01-07 18:42 ` Tony Luck
2011-01-07 20:30   ` Marco Stornelli
2011-01-07 21:59     ` Tony Luck
2011-01-08  8:16       ` Marco Stornelli [this message]
2011-01-10  8:08         ` Pavel Machek
2011-01-10  8:14           ` Marco Stornelli
2011-01-10 17:35           ` Luck, Tony
2011-01-10 18:17             ` Marco Stornelli
2011-01-11 15:42         ` Roberto A. Foglietta

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