Re: [Ext2-devel] Re: [RFC/RFT] [PATCH] EXT3: Retry allocation after journal commit

[Andrew Morton <akpm@osdl.org>]

"Theodore Ts'o" <tytso@mit.edu> wrote:
>
> On Thu, May 13, 2004 at 07:53:10PM -0700, Andrew Morton wrote:
> > "Theodore Ts'o" <tytso@mit.edu> wrote:
> > >
> > > It is possible for block allocation to fail, even if there is space in
> > >  the filesystem, because all of the free blocks were recently deleted and
> > >  so could not be allocated until after the currently running transaction
> > >  is committed.   This can result in a very strange and surprising result
> > >  where a system call such as a mkdir() will fail even though there is
> > >  plenty of disk space apparently available.
> > 
> > I merged a little patch for this into post-2.6.6, but that only addresses
> > prepare_write().
> 
> Oh, sorry, I didn't see that patch.

Andreas's patch is a bit sneaky: it simply sets ->h_sync on the current
transaction then does journal_stop().  I think your patch can do the same
thing?

again:
	handle = ext3_journal_start(...);

	...

	if (err == -ENOSPC && ext3_should_retry_alloc(inode, handle, &retry)) {
		goto again;
	} else {
		err2 = ext3_journal_stop(handle);
		if (!err)
			err = err2;
	}
	return err;

Something like that.