Commit 578bd4ce authored by Darrick J. Wong's avatar Darrick J. Wong
Browse files

xfs: recompute growfsrtfree transaction reservation while growing rt volume 



While playing with growfs to create a 20TB realtime section on a
filesystem that didn't previously have an rt section, I noticed that
growfs would occasionally shut down the log due to a transaction
reservation overflow.

xfs_calc_growrtfree_reservation uses the current size of the realtime
summary file (m_rsumsize) to compute the transaction reservation for a
growrtfree transaction.  The reservations are computed at mount time,
which means that m_rsumsize is zero when growfs starts "freeing" the new
realtime extents into the rt volume.  As a result, the transaction is
undersized and fails.

Fix this by recomputing the transaction reservations every time we
change m_rsumsize.

Signed-off-by: default avatarDarrick J. Wong <djwong@kernel.org>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
parent 18793e05

fs/xfs/xfs_rtalloc.c

+5 −0
Original line number Diff line number Diff line
@@ -1038,6 +1038,9 @@ xfs_growfs_rt( 
		nrsumblocks = xfs_rtsummary_blockcount(mp, nrsumlevels,

				nsbp->sb_rbmblocks);

		nmp->m_rsumsize = nrsumsize = XFS_FSB_TO_B(mp, nrsumblocks);

		/* recompute growfsrt reservation from new rsumsize */

		xfs_trans_resv_calc(nmp, &nmp->m_resv);



		/*

		 * Start a transaction, get the log reservation.

		 */
@@ -1124,6 +1127,8 @@ xfs_growfs_rt( 
		 */

		mp->m_rsumlevels = nrsumlevels;

		mp->m_rsumsize = nrsumsize;

		/* recompute growfsrt reservation from new rsumsize */

		xfs_trans_resv_calc(mp, &mp->m_resv);



		error = xfs_trans_commit(tp);

		if (error)