lkml.org 
[lkml]   [2002]   [Sep]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: 2.4.20pre5aa1
On Thu, Sep 05, 2002 at 09:06:00PM +0200, Andrea Arcangeli wrote:
> On Thu, Sep 05, 2002 at 07:48:24PM +0100, Christoph Hellwig wrote:
> > On Thu, Sep 05, 2002 at 08:41:25PM +0200, Andrea Arcangeli wrote:
> > > other fs, if you're not holding the i_sem (and you certainly aren't
> > > holding the i_sem that frequently, you don't even for writes).
> >
> > Except of O_DIRECT writes we _do_ hold i_sem, btw.
>
> can't you end with this?
>
> O_DIRECT write
> write finishes
> truncate drops the write
> truncate set i_sem to 0
> write set i_sem to something

s/i_sem/i_size/g ?

> and the fs is then corrupt? (very minor corruption of course and
> extremely hard to trigger, trivially solvable by an fsck, ext[23] had
> similar issues too with the get_block failures with < PAGE_SIZE
> softblocksize, fixed around 2.4.19, that was certainly easier to
> reproduce btw)

Won't happen:


O_DIRECT write starts
+ takes XFS iolock exclusive
- invalidates pagecache
+ downgrades iolock to shared
- perform write

xfs_setattr for truncate called
+ takes XFS iolock shared
-> blocks

- write i_size to something
+ releases iolock
-> gets woken

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:28    [W:0.098 / U:5.480 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site