Re: [PATCH 3/4] xfs: handle allocation failure in xfs_dquot_disk_alloc()

["Darrick J. Wong" <djwong@kernel.org>]

On Tue, Apr 02, 2024 at 09:41:56PM -0700, Christoph Hellwig wrote:
> > +	if (nmaps == 0) {
> > +		/*
> > +		 * Unexpected ENOSPC - the transaction reservation should have
> > +		 * guaranteed that this allocation will succeed. We don't know
> > +		 * why this happened, so just back out gracefully.
> > +		 *
> > +		 * We commit the transaction instead of cancelling it as it may
> > +		 * be dirty due to extent count upgrade. This avoids a potential
> > +		 * filesystem shutdown when this happens. We ignore any error
> > +		 * from the transaction commit - we always return -ENOSPC to the
> > +		 * caller here so we really don't care if the commit fails for
> > +		 * some unknown reason...
> > +		 */
> > +		xfs_trans_commit(tp);
> > +		return -ENOSPC;
> 
> A cancel and thus shutdown does seem like the right behavior for a trap
> for an unknown bug..

Usually this will result in the file write erroring out, right?

--D