From: "Darrick J. Wong" darrick.wong@oracle.com
commit 4f9a60c48078c0efa3459678fa8d6e050e8ada5d upstream.
When xfs_defer_capture extracts the deferred ops and transaction state from a transaction, it should record the remaining block reservations so that when we continue the dfops chain, we can reserve the same number of blocks to use. We capture the reservations for both data and realtime volumes.
This adds the requirement that every log intent item recovery function must be careful to reserve enough blocks to handle both itself and all defer ops that it can queue. On the other hand, this enables us to do away with the handwaving block estimation nonsense that was going on in xlog_finish_defer_ops.
Signed-off-by: Darrick J. Wong darrick.wong@oracle.com Reviewed-by: Christoph Hellwig hch@lst.de Reviewed-by: Brian Foster bfoster@redhat.com Signed-off-by: Chandan Babu R chandan.babu@oracle.com Acked-by: Darrick J. Wong djwong@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/xfs/libxfs/xfs_defer.c | 4 ++++ fs/xfs/libxfs/xfs_defer.h | 4 ++++ fs/xfs/xfs_log_recover.c | 21 +++------------------ 3 files changed, 11 insertions(+), 18 deletions(-)
--- a/fs/xfs/libxfs/xfs_defer.c +++ b/fs/xfs/libxfs/xfs_defer.c @@ -589,6 +589,10 @@ xfs_defer_ops_capture( dfc->dfc_tpflags = tp->t_flags & XFS_TRANS_LOWMODE; tp->t_flags &= ~XFS_TRANS_LOWMODE;
+ /* Capture the remaining block reservations along with the dfops. */ + dfc->dfc_blkres = tp->t_blk_res - tp->t_blk_res_used; + dfc->dfc_rtxres = tp->t_rtx_res - tp->t_rtx_res_used; + return dfc; }
--- a/fs/xfs/libxfs/xfs_defer.h +++ b/fs/xfs/libxfs/xfs_defer.h @@ -73,6 +73,10 @@ struct xfs_defer_capture { /* Deferred ops state saved from the transaction. */ struct list_head dfc_dfops; unsigned int dfc_tpflags; + + /* Block reservations for the data and rt devices. */ + unsigned int dfc_blkres; + unsigned int dfc_rtxres; };
/* --- a/fs/xfs/xfs_log_recover.c +++ b/fs/xfs/xfs_log_recover.c @@ -4766,27 +4766,12 @@ xlog_finish_defer_ops( { struct xfs_defer_capture *dfc, *next; struct xfs_trans *tp; - int64_t freeblks; - uint64_t resblks; int error = 0;
list_for_each_entry_safe(dfc, next, capture_list, dfc_list) { - /* - * We're finishing the defer_ops that accumulated as a result - * of recovering unfinished intent items during log recovery. - * We reserve an itruncate transaction because it is the - * largest permanent transaction type. Since we're the only - * user of the fs right now, take 93% (15/16) of the available - * free blocks. Use weird math to avoid a 64-bit division. - */ - freeblks = percpu_counter_sum(&mp->m_fdblocks); - if (freeblks <= 0) - return -ENOSPC; - - resblks = min_t(uint64_t, UINT_MAX, freeblks); - resblks = (resblks * 15) >> 4; - error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, resblks, - 0, XFS_TRANS_RESERVE, &tp); + error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, + dfc->dfc_blkres, dfc->dfc_rtxres, + XFS_TRANS_RESERVE, &tp); if (error) return error;