6.6-stable review patch. If anyone has any objections, please let me know.
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From: "Darrick J. Wong" djwong@kernel.org
commit 578bd4ce7100ae34f98c6b0147fe75cfa0dadbac upstream.
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: Darrick J. Wong djwong@kernel.org Reviewed-by: Christoph Hellwig hch@lst.de Signed-off-by: Catherine Hoang catherine.hoang@oracle.com Acked-by: Darrick J. Wong djwong@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/xfs/xfs_rtalloc.c | 5 +++++ 1 file changed, 5 insertions(+)
--- a/fs/xfs/xfs_rtalloc.c +++ b/fs/xfs/xfs_rtalloc.c @@ -1070,6 +1070,9 @@ xfs_growfs_rt( nsbp->sb_rbmblocks; nrsumblocks = XFS_B_TO_FSB(mp, nrsumsize); 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. */ @@ -1153,6 +1156,8 @@ error_cancel: */ 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)