[PATCH 26/43] xfs: check that the rtrefcount maxlevels doesn't increase when growing fs

Darrick J. Wong
2024-12-13T01:17:01Z

From: Darrick J. Wong <djwong@kernel.org>

The size of filesystem transaction reservations depends on the maximum
height (maxlevels) of the realtime btrees. Since we don't want a grow
operation to increase the reservation size enough that we'll fail the
minimum log size checks on the next mount, constrain growfs operations
if they would cause an increase in the rt refcount btree maxlevels.

Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
---
fs/xfs/xfs_fsops.c | 2 ++
fs/xfs/xfs_rtalloc.c | 2 ++
2 files changed, 4 insertions(+)

diff --git a/fs/xfs/xfs_fsops.c b/fs/xfs/xfs_fsops.c
index 9df5a09c0acd3b..455298503d0102 100644
--- a/fs/xfs/xfs_fsops.c
+++ b/fs/xfs/xfs_fsops.c
@@ -23,6 +23,7 @@
#include "xfs_trace.h"
#include "xfs_rtalloc.h"
#include "xfs_rtrmap_btree.h"
+#include "xfs_rtrefcount_btree.h"

/*
* Write new AG headers to disk. Non-transactional, but need to be
@@ -231,6 +232,7 @@ xfs_growfs_data_private(

/* Compute new maxlevels for rt btrees. */
xfs_rtrmapbt_compute_maxlevels(mp);
+ xfs_rtrefcountbt_compute_maxlevels(mp);
}

return error;
diff --git a/fs/xfs/xfs_rtalloc.c b/fs/xfs/xfs_rtalloc.c
index f5a3d5f8c948d8..a5de5405800a22 100644
--- a/fs/xfs/xfs_rtalloc.c
+++ b/fs/xfs/xfs_rtalloc.c
@@ -995,6 +995,7 @@ xfs_growfs_rt_bmblock(
*/
mp->m_features |= XFS_FEAT_REALTIME;
xfs_rtrmapbt_compute_maxlevels(mp);
+ xfs_rtrefcountbt_compute_maxlevels(mp);

kfree(nmp);
return 0;
@@ -1178,6 +1179,7 @@ xfs_growfs_check_rtgeom(
nmp->m_sb.sb_dblocks = dblocks;

xfs_rtrmapbt_compute_maxlevels(nmp);
+ xfs_rtrefcountbt_compute_maxlevels(nmp);
xfs_trans_resv_calc(nmp, M_RES(nmp));

/*