Merge tag 'xfs-6.7-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull xfs fixes from Chandan Babu:

 - Fix deadlock arising due to intent items in AIL not being cleared
   when log recovery fails

 - Fix stale data exposure bug when remapping COW fork extents to data
   fork

 - Fix deadlock when data device flush fails

 - Fix AGFL minimum size calculation

 - Select DEBUG_FS instead of XFS_DEBUG when XFS_ONLINE_SCRUB_STATS is
   selected

 - Fix corruption of log inode's extent count field when NREXT64 feature
   is enabled

* tag 'xfs-6.7-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: recovery should not clear di_flushiter unconditionally
  xfs: inode recovery does not validate the recovered inode
  xfs: fix again select in kconfig XFS_ONLINE_SCRUB_STATS
  xfs: fix internal error from AGFL exhaustion
  xfs: up(ic_sema) if flushing data device fails
  xfs: only remap the written blocks in xfs_reflink_end_cow_extent
  XFS: Update MAINTAINERS to catch all XFS documentation
  xfs: abort intent items when recovery intents fail
  xfs: factor out xfs_defer_pending_abort

1 files changed, 24 insertions, 3 deletions

diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c
index 3069194527dd..100ab5931b31 100644
--- a/fs/xfs/libxfs/xfs_alloc.c
+++ b/fs/xfs/libxfs/xfs_alloc.c
@@ -2275,16 +2275,37 @@ xfs_alloc_min_freelist(
 
 	ASSERT(mp->m_alloc_maxlevels > 0);
 
+	/*
+	 * For a btree shorter than the maximum height, the worst case is that
+	 * every level gets split and a new level is added, then while inserting
+	 * another entry to refill the AGFL, every level under the old root gets
+	 * split again. This is:
+	 *
+	 *   (full height split reservation) + (AGFL refill split height)
+	 * = (current height + 1) + (current height - 1)
+	 * = (new height) + (new height - 2)
+	 * = 2 * new height - 2
+	 *
+	 * For a btree of maximum height, the worst case is that every level
+	 * under the root gets split, then while inserting another entry to
+	 * refill the AGFL, every level under the root gets split again. This is
+	 * also:
+	 *
+	 *   2 * (current height - 1)
+	 * = 2 * (new height - 1)
+	 * = 2 * new height - 2
+	 */
+
 	/* space needed by-bno freespace btree */
 	min_free = min_t(unsigned int, levels[XFS_BTNUM_BNOi] + 1,
-				       mp->m_alloc_maxlevels);
+				       mp->m_alloc_maxlevels) * 2 - 2;
 	/* space needed by-size freespace btree */
 	min_free += min_t(unsigned int, levels[XFS_BTNUM_CNTi] + 1,
-				       mp->m_alloc_maxlevels);
+				       mp->m_alloc_maxlevels) * 2 - 2;
 	/* space needed reverse mapping used space btree */
 	if (xfs_has_rmapbt(mp))
 		min_free += min_t(unsigned int, levels[XFS_BTNUM_RMAPi] + 1,
-						mp->m_rmap_maxlevels);
+						mp->m_rmap_maxlevels) * 2 - 2;
 
 	return min_free;
 }