lkml.org 
[lkml]   [2012]   [Oct]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: [PATCH 2/3] ext4: introduce ext4_error_remove_page
Date
Hi Ted,

On Sat, Oct 27, 2012 at 06:16:26PM -0400, Theodore Ts'o wrote:
> On Fri, Oct 26, 2012 at 10:24:23PM +0000, Luck, Tony wrote:
> > > Well, we could set a new attribute bit on the file which indicates
> > > that the file has been corrupted, and this could cause any attempts to
> > > open the file to return some error until the bit has been cleared.
> >
> > That sounds a lot better than renaming/moving the file.
>
> What I would recommend is adding a
>
> #define FS_CORRUPTED_FL 0x01000000 /* File is corrupted */
>
> ... and which could be accessed and cleared via the lsattr and chattr
> programs.

Thank you for the info. This could help my next work.

> > > Application programs could also get very confused when any attempt to
> > > open or read from a file suddenly returned some new error code (EIO,
> > > or should we designate a new errno code for this purpose, so there is
> > > a better indication of what the heck was going on?)
> >
> > EIO sounds wrong ... but it is perhaps the best of the existing codes. Adding
> > a new one is also challenging too.
>
> I think we really need a different error code from EIO; it's already
> horribly overloaded already, and if this is new behavior when the
> customers get confused and call up the distribution help desk, they
> won't thank us if we further overload EIO. This is abusing one of the
> System V stream errno's, but no one else is using it:
>
> #define EADV 68 /* Advertise error */
>
> I note that we've already added a new error code:
>
> #define EHWPOISON 133 /* Memory page has hardware error */
>
> ... although the glibc shipping with Debian testing hasn't been taught
> what it is, so strerror(EHWPOISON) returns "Unknown error 133". We
> could simply allow open(2) and stat(2) return this error, although I
> wonder if we're just better off defining a new error code.

Whether we use EIO or EHWPOISON seems to be controversial. Andi likes
to use EIO because we can handle memory errors and legacy I/O errors in
the similar and integrated manner.
But personally, it's OK for me to use EHWPOISON. Obviously defining this
error code in glibc is a necessary step if we go in this direction.

Thanks,
Naoya


\
 
 \ /
  Last update: 2012-10-28 03:41    [W:0.412 / U:0.024 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site