Merge tag 'mm-stable-2023-06-24-19-15' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull mm updates from Andrew Morton:

 - Yosry Ahmed brought back some cgroup v1 stats in OOM logs

 - Yosry has also eliminated cgroup's atomic rstat flushing

 - Nhat Pham adds the new cachestat() syscall. It provides userspace
   with the ability to query pagecache status - a similar concept to
   mincore() but more powerful and with improved usability

 - Mel Gorman provides more optimizations for compaction, reducing the
   prevalence of page rescanning

 - Lorenzo Stoakes has done some maintanance work on the
   get_user_pages() interface

 - Liam Howlett continues with cleanups and maintenance work to the
   maple tree code. Peng Zhang also does some work on maple tree

 - Johannes Weiner has done some cleanup work on the compaction code

 - David Hildenbrand has contributed additional selftests for
   get_user_pages()

 - Thomas Gleixner has contributed some maintenance and optimization
   work for the vmalloc code

 - Baolin Wang has provided some compaction cleanups,

 - SeongJae Park continues maintenance work on the DAMON code

 - Huang Ying has done some maintenance on the swap code's usage of
   device refcounting

 - Christoph Hellwig has some cleanups for the filemap/directio code

 - Ryan Roberts provides two patch series which yield some
   rationalization of the kernel's access to pte entries - use the
   provided APIs rather than open-coding accesses

 - Lorenzo Stoakes has some fixes to the interaction between pagecache
   and directio access to file mappings

 - John Hubbard has a series of fixes to the MM selftesting code

 - ZhangPeng continues the folio conversion campaign

 - Hugh Dickins has been working on the pagetable handling code, mainly
   with a view to reducing the load on the mmap_lock

 - Catalin Marinas has reduced the arm64 kmalloc() minimum alignment
   from 128 to 8

 - Domenico Cerasuolo has improved the zswap reclaim mechanism by
   reorganizing the LRU management

 - Matthew Wilcox provides some fixups to make gfs2 work better with the
   buffer_head code

 - Vishal Moola also has done some folio conversion work

 - Matthew Wilcox has removed the remnants of the pagevec code - their
   functionality is migrated over to struct folio_batch

* tag 'mm-stable-2023-06-24-19-15' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (380 commits)
  mm/hugetlb: remove hugetlb_set_page_subpool()
  mm: nommu: correct the range of mmap_sem_read_lock in task_mem()
  hugetlb: revert use of page_cache_next_miss()
  Revert "page cache: fix page_cache_next/prev_miss off by one"
  mm/vmscan: fix root proactive reclaim unthrottling unbalanced node
  mm: memcg: rename and document global_reclaim()
  mm: kill [add|del]_page_to_lru_list()
  mm: compaction: convert to use a folio in isolate_migratepages_block()
  mm: zswap: fix double invalidate with exclusive loads
  mm: remove unnecessary pagevec includes
  mm: remove references to pagevec
  mm: rename invalidate_mapping_pagevec to mapping_try_invalidate
  mm: remove struct pagevec
  net: convert sunrpc from pagevec to folio_batch
  i915: convert i915_gpu_error to use a folio_batch
  pagevec: rename fbatch_count()
  mm: remove check_move_unevictable_pages()
  drm: convert drm_gem_put_pages() to use a folio_batch
  i915: convert shmem_sg_free_table() to use a folio_batch
  scatterlist: add sg_set_folio()
  ...

5 files changed, 1593 insertions, 919 deletions

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index b9cb205ce3f8..376784ad3545 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -2315,9 +2315,13 @@ config TEST_XARRAY
 	tristate "Test the XArray code at runtime"
 
 config TEST_MAPLE_TREE
-	depends on DEBUG_KERNEL
-	select DEBUG_MAPLE_TREE
-	tristate "Test the Maple Tree code at runtime"
+	tristate "Test the Maple Tree code at runtime or module load"
+	help
+	  Enable this option to test the maple tree code functions at boot, or
+	  when the module is loaded. Enable "Debug Maple Trees" will enable
+	  more verbose output on failures.
+
+	  If unsure, say N.
 
 config TEST_RHASHTABLE
 	tristate "Perform selftest on resizable hash table"
diff --git a/lib/Makefile b/lib/Makefile
index 0964274b075d..42d307ade225 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -30,7 +30,7 @@ endif
 lib-y := ctype.o string.o vsprintf.o cmdline.o \
 	 rbtree.o radix-tree.o timerqueue.o xarray.o \
 	 maple_tree.o idr.o extable.o irq_regs.o argv_split.o \
-	 flex_proportions.o ratelimit.o show_mem.o \
+	 flex_proportions.o ratelimit.o \
 	 is_single_threaded.o plist.o decompress.o kobject_uevent.o \
 	 earlycpio.o seq_buf.o siphash.o dec_and_lock.o \
 	 nmi_backtrace.o win_minmax.o memcat_p.o \
diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index 8ebc43d4cc8c..bfffbb7cab26 100644
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -194,7 +194,7 @@ static void mas_set_height(struct ma_state *mas)
 	unsigned int new_flags = mas->tree->ma_flags;
 
 	new_flags &= ~MT_FLAGS_HEIGHT_MASK;
-	BUG_ON(mas->depth > MAPLE_HEIGHT_MAX);
+	MAS_BUG_ON(mas, mas->depth > MAPLE_HEIGHT_MAX);
 	new_flags |= mas->depth << MT_FLAGS_HEIGHT_OFFSET;
 	mas->tree->ma_flags = new_flags;
 }
@@ -240,12 +240,12 @@ static inline void mas_set_err(struct ma_state *mas, long err)
 	mas->node = MA_ERROR(err);
 }
 
-static inline bool mas_is_ptr(struct ma_state *mas)
+static inline bool mas_is_ptr(const struct ma_state *mas)
 {
 	return mas->node == MAS_ROOT;
 }
 
-static inline bool mas_is_start(struct ma_state *mas)
+static inline bool mas_is_start(const struct ma_state *mas)
 {
 	return mas->node == MAS_START;
 }
@@ -425,28 +425,26 @@ static inline unsigned long mte_parent_slot_mask(unsigned long parent)
 }
 
 /*
- * mas_parent_enum() - Return the maple_type of the parent from the stored
+ * mas_parent_type() - Return the maple_type of the parent from the stored
  * parent type.
  * @mas: The maple state
- * @node: The maple_enode to extract the parent's enum
+ * @enode: The maple_enode to extract the parent's enum
  * Return: The node->parent maple_type
  */
 static inline
-enum maple_type mte_parent_enum(struct maple_enode *p_enode,
-				struct maple_tree *mt)
+enum maple_type mas_parent_type(struct ma_state *mas, struct maple_enode *enode)
 {
 	unsigned long p_type;
 
-	p_type = (unsigned long)p_enode;
-	if (p_type & MAPLE_PARENT_ROOT)
-		return 0; /* Validated in the caller. */
+	p_type = (unsigned long)mte_to_node(enode)->parent;
+	if (WARN_ON(p_type & MAPLE_PARENT_ROOT))
+		return 0;
 
 	p_type &= MAPLE_NODE_MASK;
-	p_type = p_type & ~(MAPLE_PARENT_ROOT | mte_parent_slot_mask(p_type));
-
+	p_type &= ~mte_parent_slot_mask(p_type);
 	switch (p_type) {
 	case MAPLE_PARENT_RANGE64: /* or MAPLE_PARENT_ARANGE64 */
-		if (mt_is_alloc(mt))
+		if (mt_is_alloc(mas->tree))
 			return maple_arange_64;
 		return maple_range_64;
 	}
@@ -454,14 +452,8 @@ enum maple_type mte_parent_enum(struct maple_enode *p_enode,
 	return 0;
 }
 
-static inline
-enum maple_type mas_parent_enum(struct ma_state *mas, struct maple_enode *enode)
-{
-	return mte_parent_enum(ma_enode_ptr(mte_to_node(enode)->parent), mas->tree);
-}
-
 /*
- * mte_set_parent() - Set the parent node and encode the slot
+ * mas_set_parent() - Set the parent node and encode the slot
  * @enode: The encoded maple node.
  * @parent: The encoded maple node that is the parent of @enode.
  * @slot: The slot that @enode resides in @parent.
@@ -470,16 +462,16 @@ enum maple_type mas_parent_enum(struct ma_state *mas, struct maple_enode *enode)
  * parent type.
  */
 static inline
-void mte_set_parent(struct maple_enode *enode, const struct maple_enode *parent,
-		    unsigned char slot)
+void mas_set_parent(struct ma_state *mas, struct maple_enode *enode,
+		    const struct maple_enode *parent, unsigned char slot)
 {
 	unsigned long val = (unsigned long)parent;
 	unsigned long shift;
 	unsigned long type;
 	enum maple_type p_type = mte_node_type(parent);
 
-	BUG_ON(p_type == maple_dense);
-	BUG_ON(p_type == maple_leaf_64);
+	MAS_BUG_ON(mas, p_type == maple_dense);
+	MAS_BUG_ON(mas, p_type == maple_leaf_64);
 
 	switch (p_type) {
 	case maple_range_64:
@@ -671,22 +663,22 @@ static inline unsigned long *ma_gaps(struct maple_node *node,
 }
 
 /*
- * mte_pivot() - Get the pivot at @piv of the maple encoded node.
- * @mn: The maple encoded node.
+ * mas_pivot() - Get the pivot at @piv of the maple encoded node.
+ * @mas: The maple state.
  * @piv: The pivot.
  *
  * Return: the pivot at @piv of @mn.
  */
-static inline unsigned long mte_pivot(const struct maple_enode *mn,
-				 unsigned char piv)
+static inline unsigned long mas_pivot(struct ma_state *mas, unsigned char piv)
 {
-	struct maple_node *node = mte_to_node(mn);
-	enum maple_type type = mte_node_type(mn);
+	struct maple_node *node = mas_mn(mas);
+	enum maple_type type = mte_node_type(mas->node);
 
-	if (piv >= mt_pivots[type]) {
-		WARN_ON(1);
+	if (MAS_WARN_ON(mas, piv >= mt_pivots[type])) {
+		mas_set_err(mas, -EIO);
 		return 0;
 	}
+
 	switch (type) {
 	case maple_arange_64:
 		return node->ma64.pivot[piv];
@@ -971,8 +963,6 @@ static inline unsigned char ma_meta_end(struct maple_node *mn,
 static inline unsigned char ma_meta_gap(struct maple_node *mn,
 					enum maple_type mt)
 {
-	BUG_ON(mt != maple_arange_64);
-
 	return mn->ma64.meta.gap;
 }
 
@@ -1111,7 +1101,6 @@ static int mas_ascend(struct ma_state *mas)
 	enum maple_type a_type;
 	unsigned long min, max;
 	unsigned long *pivots;
-	unsigned char offset;
 	bool set_max = false, set_min = false;
 
 	a_node = mas_mn(mas);
@@ -1123,8 +1112,9 @@ static int mas_ascend(struct ma_state *mas)
 	p_node = mte_parent(mas->node);
 	if (unlikely(a_node == p_node))
 		return 1;
-	a_type = mas_parent_enum(mas, mas->node);
-	offset = mte_parent_slot(mas->node);
+
+	a_type = mas_parent_type(mas, mas->node);
+	mas->offset = mte_parent_slot(mas->node);
 	a_enode = mt_mk_node(p_node, a_type);
 
 	/* Check to make sure all parent information is still accurate */
@@ -1132,7 +1122,6 @@ static int mas_ascend(struct ma_state *mas)
 		return 1;
 
 	mas->node = a_enode;
-	mas->offset = offset;
 
 	if (mte_is_root(a_enode)) {
 		mas->max = ULONG_MAX;
@@ -1140,11 +1129,17 @@ static int mas_ascend(struct ma_state *mas)
 		return 0;
 	}
 
+	if (!mas->min)
+		set_min = true;
+
+	if (mas->max == ULONG_MAX)
+		set_max = true;
+
 	min = 0;
 	max = ULONG_MAX;
 	do {
 		p_enode = a_enode;
-		a_type = mas_parent_enum(mas, p_enode);
+		a_type = mas_parent_type(mas, p_enode);
 		a_node = mte_parent(p_enode);
 		a_slot = mte_parent_slot(p_enode);
 		a_enode = mt_mk_node(a_node, a_type);
@@ -1401,9 +1396,9 @@ static inline struct maple_enode *mas_start(struct ma_state *mas)
 
 		mas->min = 0;
 		mas->max = ULONG_MAX;
-		mas->depth = 0;
 
 retry:
+		mas->depth = 0;
 		root = mas_root(mas);
 		/* Tree with nodes */
 		if (likely(xa_is_node(root))) {
@@ -1631,6 +1626,7 @@ static inline unsigned long mas_max_gap(struct ma_state *mas)
 		return mas_leaf_max_gap(mas);
 
 	node = mas_mn(mas);
+	MAS_BUG_ON(mas, mt != maple_arange_64);
 	offset = ma_meta_gap(node, mt);
 	if (offset == MAPLE_ARANGE64_META_MAX)
 		return 0;
@@ -1659,11 +1655,12 @@ static inline void mas_parent_gap(struct ma_state *mas, unsigned char offset,
 	enum maple_type pmt;
 
 	pnode = mte_parent(mas->node);
-	pmt = mas_parent_enum(mas, mas->node);
+	pmt = mas_parent_type(mas, mas->node);
 	penode = mt_mk_node(pnode, pmt);
 	pgaps = ma_gaps(pnode, pmt);
 
 ascend:
+	MAS_BUG_ON(mas, pmt != maple_arange_64);
 	meta_offset = ma_meta_gap(pnode, pmt);
 	if (meta_offset == MAPLE_ARANGE64_META_MAX)
 		meta_gap = 0;
@@ -1691,7 +1688,7 @@ ascend:
 
 	/* Go to the parent node. */
 	pnode = mte_parent(penode);
-	pmt = mas_parent_enum(mas, penode);
+	pmt = mas_parent_type(mas, penode);
 	pgaps = ma_gaps(pnode, pmt);
 	offset = mte_parent_slot(penode);
 	penode = mt_mk_node(pnode, pmt);
@@ -1718,7 +1715,7 @@ static inline void mas_update_gap(struct ma_state *mas)
 
 	pslot = mte_parent_slot(mas->node);
 	p_gap = ma_gaps(mte_parent(mas->node),
-			mas_parent_enum(mas, mas->node))[pslot];
+			mas_parent_type(mas, mas->node))[pslot];
 
 	if (p_gap != max_gap)
 		mas_parent_gap(mas, pslot, max_gap);
@@ -1743,7 +1740,7 @@ static inline void mas_adopt_children(struct ma_state *mas,
 	offset = ma_data_end(node, type, pivots, mas->max);
 	do {
 		child = mas_slot_locked(mas, slots, offset);
-		mte_set_parent(child, parent, offset);
+		mas_set_parent(mas, child, parent, offset);
 	} while (offset--);
 }
 
@@ -1755,7 +1752,7 @@ static inline void mas_adopt_children(struct ma_state *mas,
  * leave the node (true) and handle the adoption and free elsewhere.
  */
 static inline void mas_replace(struct ma_state *mas, bool advanced)
-	__must_hold(mas->tree->lock)
+	__must_hold(mas->tree->ma_lock)
 {
 	struct maple_node *mn = mas_mn(mas);
 	struct maple_enode *old_enode;
@@ -1767,7 +1764,7 @@ static inline void mas_replace(struct ma_state *mas, bool advanced)
 	} else {
 		offset = mte_parent_slot(mas->node);
 		slots = ma_slots(mte_parent(mas->node),
-				 mas_parent_enum(mas, mas->node));
+				 mas_parent_type(mas, mas->node));
 		old_enode = mas_slot_locked(mas, slots, offset);
 	}
 
@@ -1795,7 +1792,7 @@ static inline void mas_replace(struct ma_state *mas, bool advanced)
  * @child: the maple state to store the child.
  */
 static inline bool mas_new_child(struct ma_state *mas, struct ma_state *child)
-	__must_hold(mas->tree->lock)
+	__must_hold(mas->tree->ma_lock)
 {
 	enum maple_type mt;
 	unsigned char offset;
@@ -1943,8 +1940,9 @@ static inline int mab_calc_split(struct ma_state *mas,
 		 * causes one node to be deficient.
 		 * NOTE: mt_min_slots is 1 based, b_end and split are zero.
 		 */
-		while (((bn->pivot[split] - min) < slot_count - 1) &&
-		       (split < slot_count - 1) && (b_end - split > slot_min))
+		while ((split < slot_count - 1) &&
+		       ((bn->pivot[split] - min) < slot_count - 1) &&
+		       (b_end - split > slot_min))
 			split++;
 	}
 
@@ -2347,7 +2345,8 @@ static inline void mas_topiary_range(struct ma_state *mas,
 	void __rcu **slots;
 	unsigned char offset;
 
-	MT_BUG_ON(mas->tree, mte_is_leaf(mas->node));
+	MAS_BUG_ON(mas, mte_is_leaf(mas->node));
+
 	slots = ma_slots(mas_mn(mas), mte_node_type(mas->node));
 	for (offset = start; offset <= end; offset++) {
 		struct maple_enode *enode = mas_slot_locked(mas, slots, offset);
@@ -2707,9 +2706,9 @@ static inline void mas_set_split_parent(struct ma_state *mas,
 		return;
 
 	if ((*slot) <= split)
-		mte_set_parent(mas->node, left, *slot);
+		mas_set_parent(mas, mas->node, left, *slot);
 	else if (right)
-		mte_set_parent(mas->node, right, (*slot) - split - 1);
+		mas_set_parent(mas, mas->node, right, (*slot) - split - 1);
 
 	(*slot)++;
 }
@@ -3106,12 +3105,12 @@ static int mas_spanning_rebalance(struct ma_state *mas,
 				mte_node_type(mast->orig_l->node));
 	mast->orig_l->depth++;
 	mab_mas_cp(mast->bn, 0, mt_slots[mast->bn->type] - 1, &l_mas, true);
-	mte_set_parent(left, l_mas.node, slot);
+	mas_set_parent(mas, left, l_mas.node, slot);
 	if (middle)
-		mte_set_parent(middle, l_mas.node, ++slot);
+		mas_set_parent(mas, middle, l_mas.node, ++slot);
 
 	if (right)
-		mte_set_parent(right, l_mas.node, ++slot);
+		mas_set_parent(mas, right, l_mas.node, ++slot);
 
 	if (mas_is_root_limits(mast->l)) {
 new_root:
@@ -3250,7 +3249,7 @@ static inline void mas_destroy_rebalance(struct ma_state *mas, unsigned char end
 	l_mas.max = l_pivs[split];
 	mas->min = l_mas.max + 1;
 	eparent = mt_mk_node(mte_parent(l_mas.node),
-			     mas_parent_enum(&l_mas, l_mas.node));
+			     mas_parent_type(&l_mas, l_mas.node));
 	tmp += end;
 	if (!in_rcu) {
 		unsigned char max_p = mt_pivots[mt];
@@ -3293,7 +3292,7 @@ static inline void mas_destroy_rebalance(struct ma_state *mas, unsigned char end
 
 	/* replace parent. */
 	offset = mte_parent_slot(mas->node);
-	mt = mas_parent_enum(&l_mas, l_mas.node);
+	mt = mas_parent_type(&l_mas, l_mas.node);
 	parent = mas_pop_node(mas);
 	slots = ma_slots(parent, mt);
 	pivs = ma_pivots(parent, mt);
@@ -3338,8 +3337,8 @@ static inline bool mas_split_final_node(struct maple_subtree_state *mast,
 	 * The Big_node data should just fit in a single node.
 	 */
 	ancestor = mas_new_ma_node(mas, mast->bn);
-	mte_set_parent(mast->l->node, ancestor, mast->l->offset);
-	mte_set_parent(mast->r->node, ancestor, mast->r->offset);
+	mas_set_parent(mas, mast->l->node, ancestor, mast->l->offset);
+	mas_set_parent(mas, mast->r->node, ancestor, mast->r->offset);
 	mte_to_node(ancestor)->parent = mas_mn(mas)->parent;
 
 	mast->l->node = ancestor;
@@ -3729,43 +3728,31 @@ static inline void mas_store_root(struct ma_state *mas, void *entry)
  */
 static bool mas_is_span_wr(struct ma_wr_state *wr_mas)
 {
-	unsigned long max;
+	unsigned long max = wr_mas->r_max;
 	unsigned long last = wr_mas->mas->last;
-	unsigned long piv = wr_mas->r_max;
 	enum maple_type type = wr_mas->type;
 	void *entry = wr_mas->entry;
 
-	/* Contained in this pivot */
-	if (piv > last)
+	/* Contained in this pivot, fast path */
+	if (last < max)
 		return false;
 
-	max = wr_mas->mas->max;
-	if (unlikely(ma_is_leaf(type))) {
-		/* Fits in the node, but may span slots. */
+	if (ma_is_leaf(type)) {
+		max = wr_mas->mas->max;
 		if (last < max)
 			return false;
+	}
 
-		/* Writes to the end of the node but not null. */
-		if ((last == max) && entry)
-			return false;
-
+	if (last == max) {
 		/*
-		 * Writing ULONG_MAX is not a spanning write regardless of the
-		 * value being written as long as the range fits in the node.
+		 * The last entry of leaf node cannot be NULL unless it is the
+		 * rightmost node (writing ULONG_MAX), otherwise it spans slots.
 		 */
-		if ((last == ULONG_MAX) && (last == max))
-			return false;
-	} else if (piv == last) {
-		if (entry)
-			return false;
-
-		/* Detect spanning store wr walk */
-		if (last == ULONG_MAX)
+		if (entry || last == ULONG_MAX)
 			return false;
 	}
 
-	trace_ma_write(__func__, wr_mas->mas, piv, entry);
-
+	trace_ma_write(__func__, wr_mas->mas, wr_mas->r_max, entry);
 	return true;
 }
 
@@ -4087,52 +4074,27 @@ static inline int mas_wr_spanning_store(struct ma_wr_state *wr_mas)
  *
  * Return: True if stored, false otherwise
  */
-static inline bool mas_wr_node_store(struct ma_wr_state *wr_mas)
+static inline bool mas_wr_node_store(struct ma_wr_state *wr_mas,
+				     unsigned char new_end)
 {
 	struct ma_state *mas = wr_mas->mas;
 	void __rcu **dst_slots;
 	unsigned long *dst_pivots;
-	unsigned char dst_offset;
-	unsigned char new_end = wr_mas->node_end;
-	unsigned char offset;
-	unsigned char node_slots = mt_slots[wr_mas->type];
+	unsigned char dst_offset, offset_end = wr_mas->offset_end;
 	struct maple_node reuse, *newnode;
-	unsigned char copy_size, max_piv = mt_pivots[wr_mas->type];
+	unsigned char copy_size, node_pivots = mt_pivots[wr_mas->type];
 	bool in_rcu = mt_in_rcu(mas->tree);
 
-	offset = mas->offset;
-	if (mas->last == wr_mas->r_max) {
-		/* runs right to the end of the node */
-		if (mas->last == mas->max)
-			new_end = offset;
-		/* don't copy this offset */
-		wr_mas->offset_end++;
-	} else if (mas->last < wr_mas->r_max) {
-		/* new range ends in this range */
-		if (unlikely(wr_mas->r_max == ULONG_MAX))
-			mas_bulk_rebalance(mas, wr_mas->node_end, wr_mas->type);
-
-		new_end++;
-	} else {
-		if (wr_mas->end_piv == mas->last)
-			wr_mas->offset_end++;
-
-		new_end -= wr_mas->offset_end - offset - 1;
-	}
-
-	/* new range starts within a range */
-	if (wr_mas->r_min < mas->index)
-		new_end++;
-
-	/* Not enough room */
-	if (new_end >= node_slots)
-		return false;
-
-	/* Not enough data. */
+	/* Check if there is enough data. The room is enough. */
 	if (!mte_is_root(mas->node) && (new_end <= mt_min_slots[wr_mas->type]) &&
 	    !(mas->mas_flags & MA_STATE_BULK))
 		return false;
 
+	if (mas->last == wr_mas->end_piv)
+		offset_end++; /* don't copy this offset */
+	else if (unlikely(wr_mas->r_max == ULONG_MAX))
+		mas_bulk_rebalance(mas, wr_mas->node_end, wr_mas->type);
+
 	/* set up node. */
 	if (in_rcu) {
 		mas_node_count(mas, 1);
@@ -4149,47 +4111,36 @@ static inline bool mas_wr_node_store(struct ma_wr_state *wr_mas)
 	dst_pivots = ma_pivots(newnode, wr_mas->type);
 	dst_slots = ma_slots(newnode, wr_mas->type);
 	/* Copy from start to insert point */
-	memcpy(dst_pivots, wr_mas->pivots, sizeof(unsigned long) * (offset + 1));
-	memcpy(dst_slots, wr_mas->slots, sizeof(void *) * (offset + 1));
-	dst_offset = offset;
+	memcpy(dst_pivots, wr_mas->pivots, sizeof(unsigned long) * mas->offset);
+	memcpy(dst_slots, wr_mas->slots, sizeof(void *) * mas->offset);
 
 	/* Handle insert of new range starting after old range */
 	if (wr_mas->r_min < mas->index) {
-		mas->offset++;
-		rcu_assign_pointer(dst_slots[dst_offset], wr_mas->content);
-		dst_pivots[dst_offset++] = mas->index - 1;
+		rcu_assign_pointer(dst_slots[mas->offset], wr_mas->content);
+		dst_pivots[mas->offset++] = mas->index - 1;
 	}
 
 	/* Store the new entry and range end. */
-	if (dst_offset < max_piv)
-		dst_pivots[dst_offset] = mas->last;
-	mas->offset = dst_offset;
-	rcu_assign_pointer(dst_slots[dst_offset], wr_mas->entry);
+	if (mas->offset < node_pivots)
+		dst_pivots[mas->offset] = mas->last;
+	rcu_assign_pointer(dst_slots[mas->offset], wr_mas->entry);
 
 	/*
 	 * this range wrote to the end of the node or it overwrote the rest of
 	 * the data
 	 */
-	if (wr_mas->offset_end > wr_mas->node_end || mas->last >= mas->max) {
-		new_end = dst_offset;
+	if (offset_end > wr_mas->node_end)
 		goto done;
-	}
 
-	dst_offset++;
+	dst_offset = mas->offset + 1;
 	/* Copy to the end of node if necessary. */
-	copy_size = wr_mas->node_end - wr_mas->offset_end + 1;
-	memcpy(dst_slots + dst_offset, wr_mas->slots + wr_mas->offset_end,
+	copy_size = wr_mas->node_end - offset_end + 1;
+	memcpy(dst_slots + dst_offset, wr_mas->slots + offset_end,
 	       sizeof(void *) * copy_size);
-	if (dst_offset < max_piv) {
-		if (copy_size > max_piv - dst_offset)
-			copy_size = max_piv - dst_offset;
-
-		memcpy(dst_pivots + dst_offset,
-		       wr_mas->pivots + wr_mas->offset_end,
-		       sizeof(unsigned long) * copy_size);
-	}
+	memcpy(dst_pivots + dst_offset, wr_mas->pivots + offset_end,
+	       sizeof(unsigned long) * (copy_size - 1));
 
-	if ((wr_mas->node_end == node_slots - 1) && (new_end < node_slots - 1))
+	if (new_end < node_pivots)
 		dst_pivots[new_end] = mas->max;
 
 done:
@@ -4215,59 +4166,46 @@ done:
 static inline bool mas_wr_slot_store(struct ma_wr_state *wr_mas)
 {
 	struct ma_state *mas = wr_mas->mas;
-	unsigned long lmax; /* Logical max. */
 	unsigned char offset = mas->offset;
+	bool gap = false;
 
-	if ((wr_mas->r_max > mas->last) && ((wr_mas->r_min != mas->index) ||
-				  (offset != wr_mas->node_end)))
-		return false;
-
-	if (offset == wr_mas->node_end - 1)
-		lmax = mas->max;
-	else
-		lmax = wr_mas->pivots[offset + 1];
-
-	/* going to overwrite too many slots. */
-	if (lmax < mas->last)
+	if (wr_mas->offset_end - offset != 1)
 		return false;
 
-	if (wr_mas->r_min == mas->index) {
-		/* overwriting two or more ranges with one. */
-		if (lmax == mas->last)
-			return false;
+	gap |= !mt_slot_locked(mas->tree, wr_mas->slots, offset);
+	gap |= !mt_slot_locked(mas->tree, wr_mas->slots, offset + 1);
 
-		/* Overwriting all of offset and a portion of offset + 1. */
+	if (mas->index == wr_mas->r_min) {
+		/* Overwriting the range and over a part of the next range. */
 		rcu_assign_pointer(wr_mas->slots[offset], wr_mas->entry);
 		wr_mas->pivots[offset] = mas->last;
-		goto done;
+	} else {
+		/* Overwriting a part of the range and over the next range */
+		rcu_assign_pointer(wr_mas->slots[offset + 1], wr_mas->entry);
+		wr_mas->pivots[offset] = mas->index - 1;
+		mas->offset++; /* Keep mas accurate. */
 	}
 
-	/* Doesn't end on the next range end. */
-	if (lmax != mas->last)
-		return false;
-
-	/* Overwriting a portion of offset and all of offset + 1 */
-	if ((offset + 1 < mt_pivots[wr_mas->type]) &&
-	    (wr_mas->entry || wr_mas->pivots[offset + 1]))
-		wr_mas->pivots[offset + 1] = mas->last;
-
-	rcu_assign_pointer(wr_mas->slots[offset + 1], wr_mas->entry);
-	wr_mas->pivots[offset] = mas->index - 1;
-	mas->offset++; /* Keep mas accurate. */
-
-done:
 	trace_ma_write(__func__, mas, 0, wr_mas->entry);
-	mas_update_gap(mas);
+	/*
+	 * Only update gap when the new entry is empty or there is an empty
+	 * entry in the original two ranges.
+	 */
+	if (!wr_mas->entry || gap)
+		mas_update_gap(mas);
+
 	return true;
 }
 
 static inline void mas_wr_end_piv(struct ma_wr_state *wr_mas)
 {
-	while ((wr_mas->mas->last > wr_mas->end_piv) &&
-	       (wr_mas->offset_end < wr_mas->node_end))
-		wr_mas->end_piv = wr_mas->pivots[++wr_mas->offset_end];
+	while ((wr_mas->offset_end < wr_mas->node_end) &&
+	       (wr_mas->mas->last > wr_mas->pivots[wr_mas->offset_end]))
+		wr_mas->offset_end++;
 
-	if (wr_mas->mas->last > wr_mas->end_piv)
+	if (wr_mas->offset_end < wr_mas->node_end)
+		wr_mas->end_piv = wr_mas->pivots[wr_mas->offset_end];
+	else
 		wr_mas->end_piv = wr_mas->mas->max;
 }
 
@@ -4275,19 +4213,21 @@ static inline void mas_wr_extend_null(struct ma_wr_state *wr_mas)
 {
 	struct ma_state *mas = wr_mas->mas;
 
-	if (mas->last < wr_mas->end_piv && !wr_mas->slots[wr_mas->offset_end])
+	if (!wr_mas->slots[wr_mas->offset_end]) {
+		/* If this one is null, the next and prev are not */
 		mas->last = wr_mas->end_piv;
-
-	/* Check next slot(s) if we are overwriting the end */
-	if ((mas->last == wr_mas->end_piv) &&
-	    (wr_mas->node_end != wr_mas->offset_end) &&
-	    !wr_mas->slots[wr_mas->offset_end + 1]) {
-		wr_mas->offset_end++;
-		if (wr_mas->offset_end == wr_mas->node_end)
-			mas->last = mas->max;
-		else
-			mas->last = wr_mas->pivots[wr_mas->offset_end];
-		wr_mas->end_piv = mas->last;
+	} else {
+		/* Check next slot(s) if we are overwriting the end */
+		if ((mas->last == wr_mas->end_piv) &&
+		    (wr_mas->node_end != wr_mas->offset_end) &&
+		    !wr_mas->slots[wr_mas->offset_end + 1]) {
+			wr_mas->offset_end++;
+			if (wr_mas->offset_end == wr_mas->node_end)
+				mas->last = mas->max;
+			else
+				mas->last = wr_mas->pivots[wr_mas->offset_end];
+			wr_mas->end_piv = mas->last;
+		}
 	}
 
 	if (!wr_mas->content) {
@@ -4305,6 +4245,27 @@ static inline void mas_wr_extend_null(struct ma_wr_state *wr_mas)
 	}
 }
 
+static inline unsigned char mas_wr_new_end(struct ma_wr_state *wr_mas)
+{
+	struct ma_state *mas = wr_mas->mas;
+	unsigned char new_end = wr_mas->node_end + 2;
+
+	new_end -= wr_mas->offset_end - mas->offset;
+	if (wr_mas->r_min == mas->index)
+		new_end--;
+
+	if (wr_mas->end_piv == mas->last)
+		new_end--;
+
+	return new_end;
+}
+
+/*
+ * mas_wr_append: Attempt to append
+ * @wr_mas: the maple write state
+ *
+ * Return: True if appended, false otherwise
+ */
 static inline bool mas_wr_append(struct ma_wr_state *wr_mas)
 {
 	unsigned char end = wr_mas->node_end;
@@ -4312,34 +4273,30 @@ static inline bool mas_wr_append(struct ma_wr_state *wr_mas)
 	struct ma_state *mas = wr_mas->mas;
 	unsigned char node_pivots = mt_pivots[wr_mas->type];
 
-	if ((mas->index != wr_mas->r_min) && (mas->last == wr_mas->r_max)) {
-		if (new_end < node_pivots)
-			wr_mas->pivots[new_end] = wr_mas->pivots[end];
+	if (mas->offset != wr_mas->node_end)
+		return false;
 
-		if (new_end < node_pivots)
-			ma_set_meta(wr_mas->node, maple_leaf_64, 0, new_end);
+	if (new_end < node_pivots) {
+		wr_mas->pivots[new_end] = wr_mas->pivots[end];
+		ma_set_meta(wr_mas->node, maple_leaf_64, 0, new_end);
+	}
 
+	if (mas->last == wr_mas->r_max) {
+		/* Append to end of range */
 		rcu_assign_pointer(wr_mas->slots[new_end], wr_mas->entry);
-		mas->offset = new_end;
 		wr_mas->pivots[end] = mas->index - 1;
-
-		return true;
-	}
-
-	if ((mas->index == wr_mas->r_min) && (mas->last < wr_mas->r_max)) {
-		if (new_end < node_pivots)
-			wr_mas->pivots[new_end] = wr_mas->pivots[end];
-
+		mas->offset = new_end;
+	} else {
+		/* Append to start of range */
 		rcu_assign_pointer(wr_mas->slots[new_end], wr_mas->content);
-		if (new_end < node_pivots)
-			ma_set_meta(wr_mas->node, maple_leaf_64, 0, new_end);
-
 		wr_mas->pivots[end] = mas->last;
 		rcu_assign_pointer(wr_mas->slots[end], wr_mas->entry);
-		return true;
 	}
 
-	return false;
+	if (!wr_mas->content || !wr_mas->entry)
+		mas_update_gap(mas);
+
+	return  true;
 }
 
 /*
@@ -4360,9 +4317,8 @@ static void mas_wr_bnode(struct ma_wr_state *wr_mas)
 
 static inline void mas_wr_modify(struct ma_wr_state *wr_mas)
 {
-	unsigned char node_slots;
-	unsigned char node_size;
 	struct ma_state *mas = wr_mas->mas;
+	unsigned char new_end;
 
 	/* Direct replacement */
 	if (wr_mas->r_min == mas->index && wr_mas->r_max == mas->last) {
@@ -4372,26 +4328,22 @@ static inline void mas_wr_modify(struct ma_wr_state *wr_mas)
 		return;
 	}
 
-	/* Attempt to append */
-	node_slots = mt_slots[wr_mas->type];
-	node_size = wr_mas->node_end - wr_mas->offset_end + mas->offset + 2;
-	if (mas->max == ULONG_MAX)
-		node_size++;
-
-	/* slot and node store will not fit, go to the slow path */
-	if (unlikely(node_size >= node_slots))
+	/*
+	 * new_end exceeds the size of the maple node and cannot enter the fast
+	 * path.
+	 */
+	new_end = mas_wr_new_end(wr_mas);
+	if (new_end >= mt_slots[wr_mas->type])
 		goto slow_path;
 
-	if (wr_mas->entry && (wr_mas->node_end < node_slots - 1) &&
-	    (mas->offset == wr_mas->node_end) && mas_wr_append(wr_mas)) {
-		if (!wr_mas->content || !wr_mas->entry)
-			mas_update_gap(mas);
+	/* Attempt to append */
+	if (new_end == wr_mas->node_end + 1 && mas_wr_append(wr_mas))
 		return;
-	}
 
-	if ((wr_mas->offset_end - mas->offset <= 1) && mas_wr_slot_store(wr_mas))
+	if (new_end == wr_mas->node_end && mas_wr_slot_store(wr_mas))
 		return;
-	else if (mas_wr_node_store(wr_mas))
+
+	if (mas_wr_node_store(wr_mas, new_end))
 		return;
 
 	if (mas_is_err(mas))
@@ -4424,7 +4376,6 @@ static inline void *mas_wr_store_entry(struct ma_wr_state *wr_mas)
 	}
 
 	/* At this point, we are at the leaf node that needs to be altered. */
-	wr_mas->end_piv = wr_mas->r_max;
 	mas_wr_end_piv(wr_mas);
 
 	if (!wr_mas->entry)
@@ -4498,6 +4449,25 @@ exists:
 
 }
 
+static inline void mas_rewalk(struct ma_state *mas, unsigned long index)
+{
+retry:
+	mas_set(mas, index);
+	mas_state_walk(mas);
+	if (mas_is_start(mas))
+		goto retry;
+}
+
+static inline bool mas_rewalk_if_dead(struct ma_state *mas,
+		struct maple_node *node, const unsigned long index)
+{
+	if (unlikely(ma_dead_node(node))) {
+		mas_rewalk(mas, index);
+		return true;
+	}
+	return false;
+}
+
 /*
  * mas_prev_node() - Find the prev non-null entry at the same level in the
  * tree.  The prev value will be mas->node[mas->offset] or MAS_NONE.
@@ -4513,15 +4483,19 @@ static inline int mas_prev_node(struct ma_state *mas, unsigned long min)
 	int offset, level;
 	void __rcu **slots;
 	struct maple_node *node;
-	struct maple_enode *enode;
 	unsigned long *pivots;
+	unsigned long max;
 
-	if (mas_is_none(mas))
-		return 0;
+	node = mas_mn(mas);
+	if (!mas->min)
+		goto no_entry;
+
+	max = mas->min - 1;
+	if (max < min)
+		goto no_entry;
 
 	level = 0;
 	do {
-		node = mas_mn(mas);
 		if (ma_is_root(node))
 			goto no_entry;
 
@@ -4530,64 +4504,41 @@ static inline int mas_prev_node(struct ma_state *mas, unsigned long min)
 			return 1;
 		offset = mas->offset;
 		level++;
+		node = mas_mn(mas);
 	} while (!offset);
 
 	offset--;
 	mt = mte_node_type(mas->node);
-	node = mas_mn(mas);
-	slots = ma_slots(node, mt);
-	pivots = ma_pivots(node, mt);
-	if (unlikely(ma_dead_node(node)))
-		return 1;
-
-	mas->max = pivots[offset];
-	if (offset)
-		mas->min = pivots[offset - 1] + 1;
-	if (unlikely(ma_dead_node(node)))
-		return 1;
-
-	if (mas->max < min)
-		goto no_entry_min;
-
 	while (level > 1) {
 		level--;
-		enode = mas_slot(mas, slots, offset);
+		slots = ma_slots(node, mt);
+		mas->node = mas_slot(mas, slots, offset);
 		if (unlikely(ma_dead_node(node)))
 			return 1;
 
-		mas->node = enode;
 		mt = mte_node_type(mas->node);
 		node = mas_mn(mas);
-		slots = ma_slots(node, mt);
 		pivots = ma_pivots(node, mt);
-		offset = ma_data_end(node, mt, pivots, mas->max);
+		offset = ma_data_end(node, mt, pivots, max);
 		if (unlikely(ma_dead_node(node)))
 			return 1;
-
-		if (offset)
-			mas->min = pivots[offset - 1] + 1;
-
-		if (offset < mt_pivots[mt])
-			mas->max = pivots[offset];
-
-		if (mas->max < min)
-			goto no_entry;
 	}
 
+	slots = ma_slots(node, mt);
 	mas->node = mas_slot(mas, slots, offset);
+	pivots = ma_pivots(node, mt);
 	if (unlikely(ma_dead_node(node)))
 		return 1;
 
+	if (likely(offset))
+		mas->min = pivots[offset - 1] + 1;
+	mas->max = max;
 	mas->offset = mas_data_end(mas);
 	if (unlikely(mte_dead_node(mas->node)))
 		return 1;
 
 	return 0;
 
-no_entry_min:
-	mas->offset = offset;
-	if (offset)
-		mas->min = pivots[offset - 1] + 1;
 no_entry:
 	if (unlikely(ma_dead_node(node)))
 		return 1;
@@ -4597,6 +4548,76 @@ no_entry:
 }
 
 /*
+ * mas_prev_slot() - Get the entry in the previous slot
+ *
+ * @mas: The maple state
+ * @max: The minimum starting range
+ *
+ * Return: The entry in the previous slot which is possibly NULL
+ */
+static void *mas_prev_slot(struct ma_state *mas, unsigned long min, bool empty)
+{
+	void *entry;
+	void __rcu **slots;
+	unsigned long pivot;
+	enum maple_type type;
+	unsigned long *pivots;
+	struct maple_node *node;
+	unsigned long save_point = mas->index;
+
+retry:
+	node = mas_mn(mas);
+	type = mte_node_type(mas->node);
+	pivots = ma_pivots(node, type);
+	if (unlikely(mas_rewalk_if_dead(mas, node, save_point)))
+		goto retry;
+
+again:
+	if (mas->min <= min) {
+		pivot = mas_safe_min(mas, pivots, mas->offset);
+
+		if (unlikely(mas_rewalk_if_dead(mas, node, save_point)))
+			goto retry;
+
+		if (pivot <= min)
+			return NULL;
+	}
+
+	if (likely(mas->offset)) {
+		mas->offset--;
+		mas->last = mas->index - 1;
+		mas->index = mas_safe_min(mas, pivots, mas->offset);
+	} else  {
+		if (mas_prev_node(mas, min)) {
+			mas_rewalk(mas, save_point);
+			goto retry;
+		}
+
+		if (mas_is_none(mas))
+			return NULL;
+
+		mas->last = mas->max;
+		node = mas_mn(mas);
+		type = mte_node_type(mas->node);
+		pivots = ma_pivots(node, type);
+		mas->index = pivots[mas->offset - 1] + 1;
+	}
+
+	slots = ma_slots(node, type);
+	entry = mas_slot(mas, slots, mas->offset);
+	if (unlikely(mas_rewalk_if_dead(mas, node, save_point)))
+		goto retry;
+
+	if (likely(entry))
+		return entry;
+
+	if (!empty)
+		goto again;
+
+	return entry;
+}
+
+/*
  * mas_next_node() - Get the next node at the same level in the tree.
  * @mas: The maple state
  * @max: The maximum pivot value to check.
@@ -4607,11 +4628,10 @@ no_entry:
 static inline int mas_next_node(struct ma_state *mas, struct maple_node *node,
 				unsigned long max)
 {
-	unsigned long min, pivot;
+	unsigned long min;
 	unsigned long *pivots;
 	struct maple_enode *enode;
 	int level = 0;
-	unsigned char offset;
 	unsigned char node_end;
 	enum maple_type mt;
 	void __rcu **slots;
@@ -4619,19 +4639,16 @@ static inline int mas_next_node(struct ma_state *mas, struct maple_node *node,
 	if (mas->max >= max)
 		goto no_entry;
 
+	min = mas->max + 1;
 	level = 0;
 	do {
 		if (ma_is_root(node))
 			goto no_entry;
 
-		min = mas->max + 1;
-		if (min > max)
-			goto no_entry;
-
+		/* Walk up. */
 		if (unlikely(mas_ascend(mas)))
 			return 1;
 
-		offset = mas->offset;
 		level++;
 		node = mas_mn(mas);
 		mt = mte_node_type(mas->node);
@@ -4640,36 +4657,37 @@ static inline int mas_next_node(struct ma_state *mas, struct maple_node *node,
 		if (unlikely(ma_dead_node(node)))
 			return 1;
 
-	} while (unlikely(offset == node_end));
+	} while (unlikely(mas->offset == node_end));
 
 	slots = ma_slots(node, mt);
-	pivot = mas_safe_pivot(mas, pivots, ++offset, mt);
-	while (unlikely(level > 1)) {
-		/* Descend, if necessary */
-		enode = mas_slot(mas, slots, offset);
-		if (unlikely(ma_dead_node(node)))
-			return 1;
+	mas->offset++;
+	enode = mas_slot(mas, slots, mas->offset);
+	if (unlikely(ma_dead_node(node)))
+		return 1;
 
-		mas->node = enode;
+	if (level > 1)
+		mas->offset = 0;
+
+	while (unlikely(level > 1)) {
 		level--;
+		mas->node = enode;
 		node = mas_mn(mas);
 		mt = mte_node_type(mas->node);
 		slots = ma_slots(node, mt);
-		pivots = ma_pivots(node, mt);
+		enode = mas_slot(mas, slots, 0);
 		if (unlikely(ma_dead_node(node)))
 			return 1;
-
-		offset = 0;
-		pivot = pivots[0];
 	}
 
-	enode = mas_slot(mas, slots, offset);
+	if (!mas->offset)
+		pivots = ma_pivots(node, mt);
+
+	mas->max = mas_safe_pivot(mas, pivots, mas->offset, mt);
 	if (unlikely(ma_dead_node(node)))
 		return 1;
 
 	mas->node = enode;
 	mas->min = min;
-	mas->max = pivot;
 	return 0;
 
 no_entry:
@@ -4681,92 +4699,88 @@ no_entry:
 }
 
 /*
- * mas_next_nentry() - Get the next node entry
- * @mas: The maple state
- * @max: The maximum value to check
- * @*range_start: Pointer to store the start of the range.
+ * mas_next_slot() - Get the entry in the next slot
  *
- * Sets @mas->offset to the offset of the next node entry, @mas->last to the
- * pivot of the entry.
+ * @mas: The maple state
+ * @max: The maximum starting range
+ * @empty: Can be empty
  *
- * Return: The next entry, %NULL otherwise
+ * Return: The entry in the next slot which is possibly NULL
  */
-static inline void *mas_next_nentry(struct ma_state *mas,
-	    struct maple_node *node, unsigned long max, enum maple_type type)
+static void *mas_next_slot(struct ma_state *mas, unsigned long max, bool empty)
 {
-	unsigned char count;
-	unsigned long pivot;
-	unsigned long *pivots;
 	void __rcu **slots;
+	unsigned long *pivots;
+	unsigned long pivot;
+	enum maple_type type;
+	struct maple_node *node;
+	unsigned char data_end;
+	unsigned long save_point = mas->last;
 	void *entry;
 
-	if (mas->last == mas->max) {
-		mas->index = mas->max;
-		return NULL;
-	}
-
-	slots = ma_slots(node, type);
+retry:
+	node = mas_mn(mas);
+	type = mte_node_type(mas->node);
 	pivots = ma_pivots(node, type);
-	count = ma_data_end(node, type, pivots, mas->max);
-	if (unlikely(ma_dead_node(node)))
-		return NULL;
-
-	mas->index = mas_safe_min(mas, pivots, mas->offset);
-	if (unlikely(ma_dead_node(node)))
-		return NULL;
-
-	if (mas->index > max)
-		return NULL;
-
-	if (mas->offset > count)
-		return NULL;
+	data_end = ma_data_end(node, type, pivots, mas->max);
+	if (unlikely(mas_rewalk_if_dead(mas, node, save_point)))
+		goto retry;
 
-	while (mas->offset < count) {
-		pivot = pivots[mas->offset];
-		entry = mas_slot(mas, slots, mas->offset);
-		if (ma_dead_node(node))
-			return NULL;
+again:
+	if (mas->max >= max) {
+		if (likely(mas->offset < data_end))
+			pivot = pivots[mas->offset];
+		else
+			return NULL; /* must be mas->max */
 
-		if (entry)
-			goto found;
+		if (unlikely(mas_rewalk_if_dead(mas, node, save_point)))
+			goto retry;
 
 		if (pivot >= max)
 			return NULL;
+	}
 
-		mas->index = pivot + 1;
+	if (likely(mas->offset < data_end)) {
+		mas->index = pivots[mas->offset] + 1;
 		mas->offset++;
-	}
+		if (likely(mas->offset < data_end))
+			mas->last = pivots[mas->offset];
+		else
+			mas->last = mas->max;
+	} else  {
+		if (mas_next_node(mas, node, max)) {
+			mas_rewalk(mas, save_point);
+			goto retry;
+		}
 
-	if (mas->index > mas->max) {
-		mas->index = mas->last;
-		return NULL;
+		if (mas_is_none(mas))
+			return NULL;
+
+		mas->offset = 0;
+		mas->index = mas->min;
+		node = mas_mn(mas);
+		type = mte_node_type(mas->node);
+		pivots = ma_pivots(node, type);
+		mas->last = pivots[0];
 	}
 
-	pivot = mas_safe_pivot(mas, pivots, mas->offset, type);
-	entry = mas_slot(mas, slots, mas->offset);
-	if (ma_dead_node(node))
-		return NULL;
+	slots = ma_slots(node, type);
+	entry = mt_slot(mas->tree, slots, mas->offset);
+	if (unlikely(mas_rewalk_if_dead(mas, node, save_point)))
+		goto retry;
 
-	if (!pivot)
-		return NULL;
+	if (entry)
+		return entry;
 
-	if (!entry)
-		return NULL;
+	if (!empty) {
+		if (!mas->offset)
+			data_end = 2;
+		goto again;
+	}
 
-found:
-	mas->last = pivot;
 	return entry;
 }
 
-static inline void mas_rewalk(struct ma_state *mas, unsigned long index)
-{
-retry:
-	mas_set(mas, index);
-	mas_state_walk(mas);
-	if (mas_is_start(mas))
-		goto retry;
-}
-
 /*
  * mas_next_entry() - Internal function to get the next entry.
  * @mas: The maple state
@@ -4781,155 +4795,10 @@ retry:
  */
 static inline void *mas_next_entry(struct ma_state *mas, unsigned long limit)
 {
-	void *entry = NULL;
-	struct maple_enode *prev_node;
-	struct maple_node *node;
-	unsigned char offset;
-	unsigned long last;
-	enum maple_type mt;
-
-	if (mas->index > limit) {
-		mas->index = mas->last = limit;
-		mas_pause(mas);
+	if (mas->last >= limit)
 		return NULL;
-	}
-	last = mas->last;
-retry:
-	offset = mas->offset;
-	prev_node = mas->node;
-	node = mas_mn(mas);
-	mt = mte_node_type(mas->node);
-	mas->offset++;
-	if (unlikely(mas->offset >= mt_slots[mt])) {
-		mas->offset = mt_slots[mt] - 1;
-		goto next_node;
-	}
-
-	while (!mas_is_none(mas)) {
-		entry = mas_next_nentry(mas, node, limit, mt);
-		if (unlikely(ma_dead_node(node))) {
-			mas_rewalk(mas, last);
-			goto retry;
-		}
 
-		if (likely(entry))
-			return entry;
-
-		if (unlikely((mas->index > limit)))
-			break;
-
-next_node:
-		prev_node = mas->node;
-		offset = mas->offset;
-		if (unlikely(mas_next_node(mas, node, limit))) {
-			mas_rewalk(mas, last);
-			goto retry;
-		}
-		mas->offset = 0;
-		node = mas_mn(mas);
-		mt = mte_node_type(mas->node);
-	}
-
-	mas->index = mas->last = limit;
-	mas->offset = offset;
-	mas->node = prev_node;
-	return NULL;
-}
-
-/*
- * mas_prev_nentry() - Get the previous node entry.
- * @mas: The maple state.
- * @limit: The lower limit to check for a value.
- *
- * Return: the entry, %NULL otherwise.
- */
-static inline void *mas_prev_nentry(struct ma_state *mas, unsigned long limit,
-				    unsigned long index)
-{
-	unsigned long pivot, min;
-	unsigned char offset;
-	struct maple_node *mn;
-	enum maple_type mt;
-	unsigned long *pivots;
-	void __rcu **slots;
-	void *entry;
-
-retry:
-	if (!mas->offset)
-		return NULL;
-
-	mn = mas_mn(mas);
-	mt = mte_node_type(mas->node);
-	offset = mas->offset - 1;
-	if (offset >= mt_slots[mt])
-		offset = mt_slots[mt] - 1;
-
-	slots = ma_slots(mn, mt);
-	pivots = ma_pivots(mn, mt);
-	if (unlikely(ma_dead_node(mn))) {
-		mas_rewalk(mas, index);
-		goto retry;
-	}
-
-	if (offset == mt_pivots[mt])
-		pivot = mas->max;
-	else
-		pivot = pivots[offset];
-
-	if (unlikely(ma_dead_node(mn))) {
-		mas_rewalk(mas, index);
-		goto retry;
-	}
-
-	while (offset && ((!mas_slot(mas, slots, offset) && pivot >= limit) ||
-	       !pivot))
-		pivot = pivots[--offset];
-
-	min = mas_safe_min(mas, pivots, offset);
-	entry = mas_slot(mas, slots, offset);
-	if (unlikely(ma_dead_node(mn))) {
-		mas_rewalk(mas, index);
-		goto retry;
-	}
-
-	if (likely(entry)) {
-		mas->offset = offset;
-		mas->last = pivot;
-		mas->index = min;
-	}
-	return entry;
-}
-
-static inline void *mas_prev_entry(struct ma_state *mas, unsigned long min)
-{
-	void *entry;
-
-	if (mas->index < min) {
-		mas->index = mas->last = min;
-		mas->node = MAS_NONE;
-		return NULL;
-	}
-retry:
-	while (likely(!mas_is_none(mas))) {
-		entry = mas_prev_nentry(mas, min, mas->index);
-		if (unlikely(mas->last < min))
-			goto not_found;
-
-		if (likely(entry))
-			return entry;
-
-		if (unlikely(mas_prev_node(mas, min))) {
-			mas_rewalk(mas, mas->index);
-			goto retry;
-		}
-
-		mas->offset++;
-	}
-
-	mas->offset--;
-not_found:
-	mas->index = mas->last = min;
-	return NULL;
+	return mas_next_slot(mas, limit, false);
 }
 
 /*
@@ -5105,24 +4974,25 @@ void *mas_walk(struct ma_state *mas)
 {
 	void *entry;
 
+	if (mas_is_none(mas) || mas_is_paused(mas) || mas_is_ptr(mas))
+		mas->node = MAS_START;
 retry:
 	entry = mas_state_walk(mas);
-	if (mas_is_start(mas))
+	if (mas_is_start(mas)) {
 		goto retry;
-
-	if (mas_is_ptr(mas)) {
+	} else if (mas_is_none(mas)) {
+		mas->index = 0;
+		mas->last = ULONG_MAX;
+	} else if (mas_is_ptr(mas)) {
 		if (!mas->index) {
 			mas->last = 0;
-		} else {
-			mas->index = 1;
-			mas->last = ULONG_MAX;
+			return entry;
 		}
-		return entry;
-	}
 
-	if (mas_is_none(mas)) {
-		mas->index = 0;
+		mas->index = 1;
 		mas->last = ULONG_MAX;
+		mas->node = MAS_NONE;
+		return NULL;
 	}
 
 	return entry;
@@ -5202,46 +5072,6 @@ static inline void mas_awalk(struct ma_state *mas, unsigned long size)
 }
 
 /*
- * mas_fill_gap() - Fill a located gap with @entry.
- * @mas: The maple state
- * @entry: The value to store
- * @slot: The offset into the node to store the @entry
- * @size: The size of the entry
- * @index: The start location
- */
-static inline void mas_fill_gap(struct ma_state *mas, void *entry,
-		unsigned char slot, unsigned long size, unsigned long *index)
-{
-	MA_WR_STATE(wr_mas, mas, entry);
-	unsigned char pslot = mte_parent_slot(mas->node);
-	struct maple_enode *mn = mas->node;
-	unsigned long *pivots;
-	enum maple_type ptype;
-	/*
-	 * mas->index is the start address for the search
-	 *  which may no longer be needed.
-	 * mas->last is the end address for the search
-	 */
-
-	*index = mas->index;
-	mas->last = mas->index + size - 1;
-
-	/*
-	 * It is possible that using mas->max and mas->min to correctly
-	 * calculate the index and last will cause an issue in the gap
-	 * calculation, so fix the ma_state here
-	 */
-	mas_ascend(mas);
-	ptype = mte_node_type(mas->node);
-	pivots = ma_pivots(mas_mn(mas), ptype);
-	mas->max = mas_safe_pivot(mas, pivots, pslot, ptype);
-	mas->min = mas_safe_min(mas, pivots, pslot);
-	mas->node = mn;
-	mas->offset = slot;
-	mas_wr_store_entry(&wr_mas);
-}
-
-/*
  * mas_sparse_area() - Internal function.  Return upper or lower limit when
  * searching for a gap in an empty tree.
  * @mas: The maple state
@@ -5289,7 +5119,10 @@ int mas_empty_area(struct ma_state *mas, unsigned long min,
 	unsigned long *pivots;
 	enum maple_type mt;
 
-	if (min >= max)
+	if (min > max)
+		return -EINVAL;
+
+	if (size == 0 || max - min < size - 1)
 		return -EINVAL;
 
 	if (mas_is_start(mas))
@@ -5338,7 +5171,10 @@ int mas_empty_area_rev(struct ma_state *mas, unsigned long min,
 {
 	struct maple_enode *last = mas->node;
 
-	if (min >= max)
+	if (min > max)
+		return -EINVAL;
+
+	if (size == 0 || max - min < size - 1)
 		return -EINVAL;
 
 	if (mas_is_start(mas)) {
@@ -5374,7 +5210,7 @@ int mas_empty_area_rev(struct ma_state *mas, unsigned long min,
 		return -EBUSY;
 
 	/* Trim the upper limit to the max. */
-	if (max <= mas->last)
+	if (max < mas->last)
 		mas->last = max;
 
 	mas->index = mas->last - size + 1;
@@ -5382,71 +5218,6 @@ int mas_empty_area_rev(struct ma_state *mas, unsigned long min,
 }
 EXPORT_SYMBOL_GPL(mas_empty_area_rev);
 
-static inline int mas_alloc(struct ma_state *mas, void *entry,
-		unsigned long size, unsigned long *index)
-{
-	unsigned long min;
-
-	mas_start(mas);
-	if (mas_is_none(mas) || mas_is_ptr(mas)) {
-		mas_root_expand(mas, entry);
-		if (mas_is_err(mas))
-			return xa_err(mas->node);
-
-		if (!mas->index)
-			return mte_pivot(mas->node, 0);
-		return mte_pivot(mas->node, 1);
-	}
-
-	/* Must be walking a tree. */
-	mas_awalk(mas, size);
-	if (mas_is_err(mas))
-		return xa_err(mas->node);
-
-	if (mas->offset == MAPLE_NODE_SLOTS)
-		goto no_gap;
-
-	/*
-	 * At this point, mas->node points to the right node and we have an
-	 * offset that has a sufficient gap.
-	 */
-	min = mas->min;
-	if (mas->offset)
-		min = mte_pivot(mas->node, mas->offset - 1) + 1;
-
-	if (mas->index < min)
-		mas->index = min;
-
-	mas_fill_gap(mas, entry, mas->offset, size, index);
-	return 0;
-
-no_gap:
-	return -EBUSY;
-}
-
-static inline int mas_rev_alloc(struct ma_state *mas, unsigned long min,
-				unsigned long max, void *entry,
-				unsigned long size, unsigned long *index)
-{
-	int ret = 0;
-
-	ret = mas_empty_area_rev(mas, min, max, size);
-	if (ret)
-		return ret;
-
-	if (mas_is_err(mas))
-		return xa_err(mas->node);
-
-	if (mas->offset == MAPLE_NODE_SLOTS)
-		goto no_gap;
-
-	mas_fill_gap(mas, entry, mas->offset, size, index);
-	return 0;
-
-no_gap:
-	return -EBUSY;
-}
-
 /*
  * mte_dead_leaves() - Mark all leaves of a node as dead.
  * @mas: The maple state
@@ -5694,9 +5465,9 @@ void *mas_store(struct ma_state *mas, void *entry)
 
 	trace_ma_write(__func__, mas, 0, entry);
 #ifdef CONFIG_DEBUG_MAPLE_TREE
-	if (mas->index > mas->last)
-		pr_err("Error %lu > %lu %p\n", mas->index, mas->last, entry);
-	MT_BUG_ON(mas->tree, mas->index > mas->last);
+	if (MAS_WARN_ON(mas, mas->index > mas->last))
+		pr_err("Error %lX > %lX %p\n", mas->index, mas->last, entry);
+
 	if (mas->index > mas->last) {
 		mas_set_err(mas, -EINVAL);
 		return NULL;
@@ -5756,7 +5527,7 @@ void mas_store_prealloc(struct ma_state *mas, void *entry)
 	mas_wr_store_setup(&wr_mas);
 	trace_ma_write(__func__, mas, 0, entry);
 	mas_wr_store_entry(&wr_mas);
-	BUG_ON(mas_is_err(mas));
+	MAS_WR_BUG_ON(&wr_mas, mas_is_err(mas));
 	mas_destroy(mas);
 }
 EXPORT_SYMBOL_GPL(mas_store_prealloc);
@@ -5808,9 +5579,7 @@ void mas_destroy(struct ma_state *mas)
 	if (mas->mas_flags & MA_STATE_REBALANCE) {
 		unsigned char end;
 
-		if (mas_is_start(mas))
-			mas_start(mas);
-
+		mas_start(mas);
 		mtree_range_walk(mas);
 		end = mas_data_end(mas) + 1;
 		if (end < mt_min_slot_count(mas->node) - 1)
@@ -5900,6 +5669,34 @@ int mas_expected_entries(struct ma_state *mas, unsigned long nr_entries)
 }
 EXPORT_SYMBOL_GPL(mas_expected_entries);
 
+static inline bool mas_next_setup(struct ma_state *mas, unsigned long max,
+		void **entry)
+{
+	bool was_none = mas_is_none(mas);
+
+	if (mas_is_none(mas) || mas_is_paused(mas))
+		mas->node = MAS_START;
+
+	if (mas_is_start(mas))
+		*entry = mas_walk(mas); /* Retries on dead nodes handled by mas_walk */
+
+	if (mas_is_ptr(mas)) {
+		*entry = NULL;
+		if (was_none && mas->index == 0) {
+			mas->index = mas->last = 0;
+			return true;
+		}
+		mas->index = 1;
+		mas->last = ULONG_MAX;
+		mas->node = MAS_NONE;
+		return true;
+	}
+
+	if (mas_is_none(mas))
+		return true;
+	return false;
+}
+
 /**
  * mas_next() - Get the next entry.
  * @mas: The maple state
@@ -5913,27 +5710,38 @@ EXPORT_SYMBOL_GPL(mas_expected_entries);
  */
 void *mas_next(struct ma_state *mas, unsigned long max)
 {
-	if (mas_is_none(mas) || mas_is_paused(mas))
-		mas->node = MAS_START;
+	void *entry = NULL;
 
-	if (mas_is_start(mas))
-		mas_walk(mas); /* Retries on dead nodes handled by mas_walk */
+	if (mas_next_setup(mas, max, &entry))
+		return entry;
 
-	if (mas_is_ptr(mas)) {
-		if (!mas->index) {
-			mas->index = 1;
-			mas->last = ULONG_MAX;
-		}
-		return NULL;
-	}
+	/* Retries on dead nodes handled by mas_next_slot */
+	return mas_next_slot(mas, max, false);
+}
+EXPORT_SYMBOL_GPL(mas_next);
 
-	if (mas->last == ULONG_MAX)
-		return NULL;
+/**
+ * mas_next_range() - Advance the maple state to the next range
+ * @mas: The maple state
+ * @max: The maximum index to check.
+ *
+ * Sets @mas->index and @mas->last to the range.
+ * Must hold rcu_read_lock or the write lock.
+ * Can return the zero entry.
+ *
+ * Return: The next entry or %NULL
+ */
+void *mas_next_range(struct ma_state *mas, unsigned long max)
+{
+	void *entry = NULL;
+
+	if (mas_next_setup(mas, max, &entry))
+		return entry;
 
-	/* Retries on dead nodes handled by mas_next_entry */
-	return mas_next_entry(mas, max);
+	/* Retries on dead nodes handled by mas_next_slot */
+	return mas_next_slot(mas, max, true);
 }
-EXPORT_SYMBOL_GPL(mas_next);
+EXPORT_SYMBOL_GPL(mas_next_range);
 
 /**
  * mt_next() - get the next value in the maple tree
@@ -5955,6 +5763,47 @@ void *mt_next(struct maple_tree *mt, unsigned long index, unsigned long max)
 }
 EXPORT_SYMBOL_GPL(mt_next);
 
+static inline bool mas_prev_setup(struct ma_state *mas, unsigned long min,
+		void **entry)
+{
+	if (mas->index <= min)
+		goto none;
+
+	if (mas_is_none(mas) || mas_is_paused(mas))
+		mas->node = MAS_START;
+
+	if (mas_is_start(mas)) {
+		mas_walk(mas);
+		if (!mas->index)
+			goto none;
+	}
+
+	if (unlikely(mas_is_ptr(mas))) {
+		if (!mas->index)
+			goto none;
+		mas->index = mas->last = 0;
+		*entry = mas_root(mas);
+		return true;
+	}
+
+	if (mas_is_none(mas)) {
+		if (mas->index) {
+			/* Walked to out-of-range pointer? */
+			mas->index = mas->last = 0;
+			mas->node = MAS_ROOT;
+			*entry = mas_root(mas);
+			return true;
+		}
+		return true;
+	}
+
+	return false;
+
+none:
+	mas->node = MAS_NONE;
+	return true;
+}
+
 /**
  * mas_prev() - Get the previous entry
  * @mas: The maple state
@@ -5968,37 +5817,37 @@ EXPORT_SYMBOL_GPL(mt_next);
  */
 void *mas_prev(struct ma_state *mas, unsigned long min)
 {
-	if (!mas->index) {
-		/* Nothing comes before 0 */
-		mas->last = 0;
-		mas->node = MAS_NONE;
-		return NULL;
-	}
+	void *entry = NULL;
 
-	if (unlikely(mas_is_ptr(mas)))
-		return NULL;
+	if (mas_prev_setup(mas, min, &entry))
+		return entry;
 
-	if (mas_is_none(mas) || mas_is_paused(mas))
-		mas->node = MAS_START;
+	return mas_prev_slot(mas, min, false);
+}
+EXPORT_SYMBOL_GPL(mas_prev);
 
-	if (mas_is_start(mas)) {
-		mas_walk(mas);
-		if (!mas->index)
-			return NULL;
-	}
+/**
+ * mas_prev_range() - Advance to the previous range
+ * @mas: The maple state
+ * @min: The minimum value to check.
+ *
+ * Sets @mas->index and @mas->last to the range.
+ * Must hold rcu_read_lock or the write lock.
+ * Will reset mas to MAS_START if the node is MAS_NONE.  Will stop on not
+ * searchable nodes.
+ *
+ * Return: the previous value or %NULL.
+ */
+void *mas_prev_range(struct ma_state *mas, unsigned long min)
+{
+	void *entry = NULL;
 
-	if (mas_is_ptr(mas)) {
-		if (!mas->index) {
-			mas->last = 0;
-			return NULL;
-		}
+	if (mas_prev_setup(mas, min, &entry))
+		return entry;
 
-		mas->index = mas->last = 0;
-		return mas_root_locked(mas);
-	}
-	return mas_prev_entry(mas, min);
+	return mas_prev_slot(mas, min, true);
 }
-EXPORT_SYMBOL_GPL(mas_prev);
+EXPORT_SYMBOL_GPL(mas_prev_range);
 
 /**
  * mt_prev() - get the previous value in the maple tree
@@ -6040,6 +5889,64 @@ void mas_pause(struct ma_state *mas)
 EXPORT_SYMBOL_GPL(mas_pause);
 
 /**
+ * mas_find_setup() - Internal function to set up mas_find*().
+ * @mas: The maple state
+ * @max: The maximum index
+ * @entry: Pointer to the entry
+ *
+ * Returns: True if entry is the answer, false otherwise.
+ */
+static inline bool mas_find_setup(struct ma_state *mas, unsigned long max,
+		void **entry)
+{
+	*entry = NULL;
+
+	if (unlikely(mas_is_none(mas))) {
+		if (unlikely(mas->last >= max))
+			return true;
+
+		mas->index = mas->last;
+		mas->node = MAS_START;
+	} else if (unlikely(mas_is_paused(mas))) {
+		if (unlikely(mas->last >= max))
+			return true;
+
+		mas->node = MAS_START;
+		mas->index = ++mas->last;
+	} else if (unlikely(mas_is_ptr(mas)))
+		goto ptr_out_of_range;
+
+	if (unlikely(mas_is_start(mas))) {
+		/* First run or continue */
+		if (mas->index > max)
+			return true;
+
+		*entry = mas_walk(mas);
+		if (*entry)
+			return true;
+
+	}
+
+	if (unlikely(!mas_searchable(mas))) {
+		if (unlikely(mas_is_ptr(mas)))
+			goto ptr_out_of_range;
+
+		return true;
+	}
+
+	if (mas->index == max)
+		return true;
+
+	return false;
+
+ptr_out_of_range:
+	mas->node = MAS_NONE;
+	mas->index = 1;
+	mas->last = ULONG_MAX;
+	return true;
+}
+
+/**
  * mas_find() - On the first call, find the entry at or after mas->index up to
  * %max.  Otherwise, find the entry after mas->index.
  * @mas: The maple state
@@ -6053,37 +5960,105 @@ EXPORT_SYMBOL_GPL(mas_pause);
  */
 void *mas_find(struct ma_state *mas, unsigned long max)
 {
+	void *entry = NULL;
+
+	if (mas_find_setup(mas, max, &entry))
+		return entry;
+
+	/* Retries on dead nodes handled by mas_next_slot */
+	return mas_next_slot(mas, max, false);
+}
+EXPORT_SYMBOL_GPL(mas_find);
+
+/**
+ * mas_find_range() - On the first call, find the entry at or after
+ * mas->index up to %max.  Otherwise, advance to the next slot mas->index.
+ * @mas: The maple state
+ * @max: The maximum value to check.
+ *
+ * Must hold rcu_read_lock or the write lock.
+ * If an entry exists, last and index are updated accordingly.
+ * May set @mas->node to MAS_NONE.
+ *
+ * Return: The entry or %NULL.
+ */
+void *mas_find_range(struct ma_state *mas, unsigned long max)
+{
+	void *entry;
+
+	if (mas_find_setup(mas, max, &entry))
+		return entry;
+
+	/* Retries on dead nodes handled by mas_next_slot */
+	return mas_next_slot(mas, max, true);
+}
+EXPORT_SYMBOL_GPL(mas_find_range);
+
+/**
+ * mas_find_rev_setup() - Internal function to set up mas_find_*_rev()
+ * @mas: The maple state
+ * @min: The minimum index
+ * @entry: Pointer to the entry
+ *
+ * Returns: True if entry is the answer, false otherwise.
+ */
+static inline bool mas_find_rev_setup(struct ma_state *mas, unsigned long min,
+		void **entry)
+{
+	*entry = NULL;
+
+	if (unlikely(mas_is_none(mas))) {
+		if (mas->index <= min)
+			goto none;
+
+		mas->last = mas->index;
+		mas->node = MAS_START;
+	}
+
 	if (unlikely(mas_is_paused(mas))) {
-		if (unlikely(mas->last == ULONG_MAX)) {
+		if (unlikely(mas->index <= min)) {
 			mas->node = MAS_NONE;
-			return NULL;
+			return true;
 		}
 		mas->node = MAS_START;
-		mas->index = ++mas->last;
+		mas->last = --mas->index;
 	}
 
-	if (unlikely(mas_is_none(mas)))
-		mas->node = MAS_START;
-
 	if (unlikely(mas_is_start(mas))) {
 		/* First run or continue */
-		void *entry;
+		if (mas->index < min)
+			return true;
 
-		if (mas->index > max)
-			return NULL;
+		*entry = mas_walk(mas);
+		if (*entry)
+			return true;
+	}
 
-		entry = mas_walk(mas);
-		if (entry)
-			return entry;
+	if (unlikely(!mas_searchable(mas))) {
+		if (mas_is_ptr(mas))
+			goto none;
+
+		if (mas_is_none(mas)) {
+			/*
+			 * Walked to the location, and there was nothing so the
+			 * previous location is 0.
+			 */
+			mas->last = mas->index = 0;
+			mas->node = MAS_ROOT;
+			*entry = mas_root(mas);
+			return true;
+		}
 	}
 
-	if (unlikely(!mas_searchable(mas)))
-		return NULL;
+	if (mas->index < min)
+		return true;
+
+	return false;
 
-	/* Retries on dead nodes handled by mas_next_entry */
-	return mas_next_entry(mas, max);
+none:
+	mas->node = MAS_NONE;
+	return true;
 }
-EXPORT_SYMBOL_GPL(mas_find);
 
 /**
  * mas_find_rev: On the first call, find the first non-null entry at or below
@@ -6100,37 +6075,41 @@ EXPORT_SYMBOL_GPL(mas_find);
  */
 void *mas_find_rev(struct ma_state *mas, unsigned long min)
 {
-	if (unlikely(mas_is_paused(mas))) {
-		if (unlikely(mas->last == ULONG_MAX)) {
-			mas->node = MAS_NONE;
-			return NULL;
-		}
-		mas->node = MAS_START;
-		mas->last = --mas->index;
-	}
+	void *entry;
 
-	if (unlikely(mas_is_start(mas))) {
-		/* First run or continue */
-		void *entry;
+	if (mas_find_rev_setup(mas, min, &entry))
+		return entry;
 
-		if (mas->index < min)
-			return NULL;
+	/* Retries on dead nodes handled by mas_prev_slot */
+	return mas_prev_slot(mas, min, false);
 
-		entry = mas_walk(mas);
-		if (entry)
-			return entry;
-	}
+}
+EXPORT_SYMBOL_GPL(mas_find_rev);
 
-	if (unlikely(!mas_searchable(mas)))
-		return NULL;
+/**
+ * mas_find_range_rev: On the first call, find the first non-null entry at or
+ * below mas->index down to %min.  Otherwise advance to the previous slot after
+ * mas->index down to %min.
+ * @mas: The maple state
+ * @min: The minimum value to check.
+ *
+ * Must hold rcu_read_lock or the write lock.
+ * If an entry exists, last and index are updated accordingly.
+ * May set @mas->node to MAS_NONE.
+ *
+ * Return: The entry or %NULL.
+ */
+void *mas_find_range_rev(struct ma_state *mas, unsigned long min)
+{
+	void *entry;
 
-	if (mas->index < min)
-		return NULL;
+	if (mas_find_rev_setup(mas, min, &entry))
+		return entry;
 
-	/* Retries on dead nodes handled by mas_prev_entry */
-	return mas_prev_entry(mas, min);
+	/* Retries on dead nodes handled by mas_prev_slot */
+	return mas_prev_slot(mas, min, true);
 }
-EXPORT_SYMBOL_GPL(mas_find_rev);
+EXPORT_SYMBOL_GPL(mas_find_range_rev);
 
 /**
  * mas_erase() - Find the range in which index resides and erase the entire
@@ -6176,7 +6155,7 @@ EXPORT_SYMBOL_GPL(mas_erase);
  * Return: true on allocation, false otherwise.
  */
 bool mas_nomem(struct ma_state *mas, gfp_t gfp)
-	__must_hold(mas->tree->lock)
+	__must_hold(mas->tree->ma_lock)
 {
 	if (likely(mas->node != MA_ERROR(-ENOMEM))) {
 		mas_destroy(mas);
@@ -6357,31 +6336,33 @@ int mtree_alloc_range(struct maple_tree *mt, unsigned long *startp,
 {
 	int ret = 0;
 
-	MA_STATE(mas, mt, min, max - size);
+	MA_STATE(mas, mt, 0, 0);
 	if (!mt_is_alloc(mt))
 		return -EINVAL;
 
 	if (WARN_ON_ONCE(mt_is_reserved(entry)))
 		return -EINVAL;
 
-	if (min > max)
-		return -EINVAL;
-
-	if (max < size)
-		return -EINVAL;
-
-	if (!size)
-		return -EINVAL;
-
 	mtree_lock(mt);
 retry:
-	mas.offset = 0;
-	mas.index = min;
-	mas.last = max - size;
-	ret = mas_alloc(&mas, entry, size, startp);
+	ret = mas_empty_area(&mas, min, max, size);
+	if (ret)
+		goto unlock;
+
+	mas_insert(&mas, entry);
+	/*
+	 * mas_nomem() may release the lock, causing the allocated area
+	 * to be unavailable, so try to allocate a free area again.
+	 */
 	if (mas_nomem(&mas, gfp))
 		goto retry;
 
+	if (mas_is_err(&mas))
+		ret = xa_err(mas.node);
+	else
+		*startp = mas.index;
+
+unlock:
 	mtree_unlock(mt);
 	return ret;
 }
@@ -6393,28 +6374,33 @@ int mtree_alloc_rrange(struct maple_tree *mt, unsigned long *startp,
 {
 	int ret = 0;
 
-	MA_STATE(mas, mt, min, max - size);
+	MA_STATE(mas, mt, 0, 0);
 	if (!mt_is_alloc(mt))
 		return -EINVAL;
 
 	if (WARN_ON_ONCE(mt_is_reserved(entry)))
 		return -EINVAL;
 
-	if (min >= max)
-		return -EINVAL;
-
-	if (max < size - 1)
-		return -EINVAL;
-
-	if (!size)
-		return -EINVAL;
-
 	mtree_lock(mt);
 retry:
-	ret = mas_rev_alloc(&mas, min, max, entry, size, startp);
+	ret = mas_empty_area_rev(&mas, min, max, size);
+	if (ret)
+		goto unlock;
+
+	mas_insert(&mas, entry);
+	/*
+	 * mas_nomem() may release the lock, causing the allocated area
+	 * to be unavailable, so try to allocate a free area again.
+	 */
 	if (mas_nomem(&mas, gfp))
 		goto retry;
 
+	if (mas_is_err(&mas))
+		ret = xa_err(mas.node);
+	else
+		*startp = mas.index;
+
+unlock:
 	mtree_unlock(mt);
 	return ret;
 }
@@ -6512,7 +6498,7 @@ retry:
 	if (entry)
 		goto unlock;
 
-	while (mas_searchable(&mas) && (mas.index < max)) {
+	while (mas_searchable(&mas) && (mas.last < max)) {
 		entry = mas_next_entry(&mas, max);
 		if (likely(entry && !xa_is_zero(entry)))
 			break;
@@ -6525,10 +6511,9 @@ unlock:
 	if (likely(entry)) {
 		*index = mas.last + 1;
 #ifdef CONFIG_DEBUG_MAPLE_TREE
-		if ((*index) && (*index) <= copy)
+		if (MT_WARN_ON(mt, (*index) && ((*index) <= copy)))
 			pr_err("index not increased! %lx <= %lx\n",
 			       *index, copy);
-		MT_BUG_ON(mt, (*index) && ((*index) <= copy));
 #endif
 	}
 
@@ -6674,7 +6659,7 @@ static inline void *mas_first_entry(struct ma_state *mas, struct maple_node *mn,
 	max = mas->max;
 	mas->offset = 0;
 	while (likely(!ma_is_leaf(mt))) {
-		MT_BUG_ON(mas->tree, mte_dead_node(mas->node));
+		MAS_WARN_ON(mas, mte_dead_node(mas->node));
 		slots = ma_slots(mn, mt);
 		entry = mas_slot(mas, slots, 0);
 		pivots = ma_pivots(mn, mt);
@@ -6685,7 +6670,7 @@ static inline void *mas_first_entry(struct ma_state *mas, struct maple_node *mn,
 		mn = mas_mn(mas);
 		mt = mte_node_type(mas->node);
 	}
-	MT_BUG_ON(mas->tree, mte_dead_node(mas->node));
+	MAS_WARN_ON(mas, mte_dead_node(mas->node));
 
 	mas->max = max;
 	slots = ma_slots(mn, mt);
@@ -6735,15 +6720,12 @@ static void mas_dfs_postorder(struct ma_state *mas, unsigned long max)
 
 	mas->node = mn;
 	mas_ascend(mas);
-	while (mas->node != MAS_NONE) {
+	do {
 		p = mas->node;
 		p_min = mas->min;
 		p_max = mas->max;
 		mas_prev_node(mas, 0);
-	}
-
-	if (p == MAS_NONE)
-		return;
+	} while (!mas_is_none(mas));
 
 	mas->node = p;
 	mas->max = p_max;
@@ -6752,22 +6734,33 @@ static void mas_dfs_postorder(struct ma_state *mas, unsigned long max)
 
 /* Tree validations */
 static void mt_dump_node(const struct maple_tree *mt, void *entry,
-		unsigned long min, unsigned long max, unsigned int depth);
+		unsigned long min, unsigned long max, unsigned int depth,
+		enum mt_dump_format format);
 static void mt_dump_range(unsigned long min, unsigned long max,
-			  unsigned int depth)
+			  unsigned int depth, enum mt_dump_format format)
 {
 	static const char spaces[] = "                                ";
 
-	if (min == max)
-		pr_info("%.*s%lu: ", depth * 2, spaces, min);
-	else
-		pr_info("%.*s%lu-%lu: ", depth * 2, spaces, min, max);
+	switch(format) {
+	case mt_dump_hex:
+		if (min == max)
+			pr_info("%.*s%lx: ", depth * 2, spaces, min);
+		else
+			pr_info("%.*s%lx-%lx: ", depth * 2, spaces, min, max);
+		break;
+	default:
+	case mt_dump_dec:
+		if (min == max)
+			pr_info("%.*s%lu: ", depth * 2, spaces, min);
+		else
+			pr_info("%.*s%lu-%lu: ", depth * 2, spaces, min, max);
+	}
 }
 
 static void mt_dump_entry(void *entry, unsigned long min, unsigned long max,
-			  unsigned int depth)
+			  unsigned int depth, enum mt_dump_format format)
 {
-	mt_dump_range(min, max, depth);
+	mt_dump_range(min, max, depth, format);
 
 	if (xa_is_value(entry))
 		pr_cont("value %ld (0x%lx) [%p]\n", xa_to_value(entry),
@@ -6781,7 +6774,8 @@ static void mt_dump_entry(void *entry, unsigned long min, unsigned long max,
 }
 
 static void mt_dump_range64(const struct maple_tree *mt, void *entry,
-			unsigned long min, unsigned long max, unsigned int depth)
+		unsigned long min, unsigned long max, unsigned int depth,
+		enum mt_dump_format format)
 {
 	struct maple_range_64 *node = &mte_to_node(entry)->mr64;
 	bool leaf = mte_is_leaf(entry);
@@ -6789,8 +6783,16 @@ static void mt_dump_range64(const struct maple_tree *mt, void *entry,
 	int i;
 
 	pr_cont(" contents: ");
-	for (i = 0; i < MAPLE_RANGE64_SLOTS - 1; i++)
-		pr_cont("%p %lu ", node->slot[i], node->pivot[i]);
+	for (i = 0; i < MAPLE_RANGE64_SLOTS - 1; i++) {
+		switch(format) {
+		case mt_dump_hex:
+			pr_cont("%p %lX ", node->slot[i], node->pivot[i]);
+			break;
+		default:
+		case mt_dump_dec:
+			pr_cont("%p %lu ", node->slot[i], node->pivot[i]);
+		}
+	}
 	pr_cont("%p\n", node->slot[i]);
 	for (i = 0; i < MAPLE_RANGE64_SLOTS; i++) {
 		unsigned long last = max;
@@ -6803,24 +6805,32 @@ static void mt_dump_range64(const struct maple_tree *mt, void *entry,
 			break;
 		if (leaf)
 			mt_dump_entry(mt_slot(mt, node->slot, i),
-					first, last, depth + 1);
+					first, last, depth + 1, format);
 		else if (node->slot[i])
 			mt_dump_node(mt, mt_slot(mt, node->slot, i),
-					first, last, depth + 1);
+					first, last, depth + 1, format);
 
 		if (last == max)
 			break;
 		if (last > max) {
-			pr_err("node %p last (%lu) > max (%lu) at pivot %d!\n",
+			switch(format) {
+			case mt_dump_hex:
+				pr_err("node %p last (%lx) > max (%lx) at pivot %d!\n",
 					node, last, max, i);
-			break;
+				break;
+			default:
+			case mt_dump_dec:
+				pr_err("node %p last (%lu) > max (%lu) at pivot %d!\n",
+					node, last, max, i);
+			}
 		}
 		first = last + 1;
 	}
 }
 
 static void mt_dump_arange64(const struct maple_tree *mt, void *entry,
-			unsigned long min, unsigned long max, unsigned int depth)
+	unsigned long min, unsigned long max, unsigned int depth,
+	enum mt_dump_format format)
 {
 	struct maple_arange_64 *node = &mte_to_node(entry)->ma64;
 	bool leaf = mte_is_leaf(entry);
@@ -6845,10 +6855,10 @@ static void mt_dump_arange64(const struct maple_tree *mt, void *entry,
 			break;
 		if (leaf)
 			mt_dump_entry(mt_slot(mt, node->slot, i),
-					first, last, depth + 1);
+					first, last, depth + 1, format);
 		else if (node->slot[i])
 			mt_dump_node(mt, mt_slot(mt, node->slot, i),
-					first, last, depth + 1);
+					first, last, depth + 1, format);
 
 		if (last == max)
 			break;
@@ -6862,13 +6872,14 @@ static void mt_dump_arange64(const struct maple_tree *mt, void *entry,
 }
 
 static void mt_dump_node(const struct maple_tree *mt, void *entry,
-		unsigned long min, unsigned long max, unsigned int depth)
+		unsigned long min, unsigned long max, unsigned int depth,
+		enum mt_dump_format format)
 {
 	struct maple_node *node = mte_to_node(entry);
 	unsigned int type = mte_node_type(entry);
 	unsigned int i;
 
-	mt_dump_range(min, max, depth);
+	mt_dump_range(min, max, depth, format);
 
 	pr_cont("node %p depth %d type %d parent %p", node, depth, type,
 			node ? node->parent : NULL);
@@ -6879,15 +6890,15 @@ static void mt_dump_node(const struct maple_tree *mt, void *entry,
 			if (min + i > max)
 				pr_cont("OUT OF RANGE: ");
 			mt_dump_entry(mt_slot(mt, node->slot, i),
-					min + i, min + i, depth);
+					min + i, min + i, depth, format);
 		}
 		break;
 	case maple_leaf_64:
 	case maple_range_64:
-		mt_dump_range64(mt, entry, min, max, depth);
+		mt_dump_range64(mt, entry, min, max, depth, format);
 		break;
 	case maple_arange_64:
-		mt_dump_arange64(mt, entry, min, max, depth);
+		mt_dump_arange64(mt, entry, min, max, depth, format);
 		break;
 
 	default:
@@ -6895,16 +6906,16 @@ static void mt_dump_node(const struct maple_tree *mt, void *entry,
 	}
 }
 
-void mt_dump(const struct maple_tree *mt)
+void mt_dump(const struct maple_tree *mt, enum mt_dump_format format)
 {
 	void *entry = rcu_dereference_check(mt->ma_root, mt_locked(mt));
 
 	pr_info("maple_tree(%p) flags %X, height %u root %p\n",
 		 mt, mt->ma_flags, mt_height(mt), entry);
 	if (!xa_is_node(entry))
-		mt_dump_entry(entry, 0, 0, 0);
+		mt_dump_entry(entry, 0, 0, 0, format);
 	else if (entry)
-		mt_dump_node(mt, entry, 0, mt_node_max(entry), 0);
+		mt_dump_node(mt, entry, 0, mt_node_max(entry), 0, format);
 }
 EXPORT_SYMBOL_GPL(mt_dump);
 
@@ -6957,7 +6968,7 @@ static void mas_validate_gaps(struct ma_state *mas)
 						mas_mn(mas), i,
 						mas_get_slot(mas, i), gap,
 						p_end, p_start);
-					mt_dump(mas->tree);
+					mt_dump(mas->tree, mt_dump_hex);
 
 					MT_BUG_ON(mas->tree,
 						gap != p_end - p_start + 1);
@@ -6988,27 +6999,29 @@ counted:
 	p_slot = mte_parent_slot(mas->node);
 	p_mn = mte_parent(mte);
 	MT_BUG_ON(mas->tree, max_gap > mas->max);
-	if (ma_gaps(p_mn, mas_parent_enum(mas, mte))[p_slot] != max_gap) {
+	if (ma_gaps(p_mn, mas_parent_type(mas, mte))[p_slot] != max_gap) {
 		pr_err("gap %p[%u] != %lu\n", p_mn, p_slot, max_gap);
-		mt_dump(mas->tree);
+		mt_dump(mas->tree, mt_dump_hex);
 	}
 
 	MT_BUG_ON(mas->tree,
-		  ma_gaps(p_mn, mas_parent_enum(mas, mte))[p_slot] != max_gap);
+		  ma_gaps(p_mn, mas_parent_type(mas, mte))[p_slot] != max_gap);
 }
 
 static void mas_validate_parent_slot(struct ma_state *mas)
 {
 	struct maple_node *parent;
 	struct maple_enode *node;
-	enum maple_type p_type = mas_parent_enum(mas, mas->node);
-	unsigned char p_slot = mte_parent_slot(mas->node);
+	enum maple_type p_type;
+	unsigned char p_slot;
 	void __rcu **slots;
 	int i;
 
 	if (mte_is_root(mas->node))
 		return;
 
+	p_slot = mte_parent_slot(mas->node);
+	p_type = mas_parent_type(mas, mas->node);
 	parent = mte_parent(mas->node);
 	slots = ma_slots(parent, p_type);
 	MT_BUG_ON(mas->tree, mas_mn(mas) == parent);
@@ -7101,18 +7114,18 @@ static void mas_validate_limits(struct ma_state *mas)
 		if (prev_piv > piv) {
 			pr_err("%p[%u] piv %lu < prev_piv %lu\n",
 				mas_mn(mas), i, piv, prev_piv);
-			MT_BUG_ON(mas->tree, piv < prev_piv);
+			MAS_WARN_ON(mas, piv < prev_piv);
 		}
 
 		if (piv < mas->min) {
 			pr_err("%p[%u] %lu < %lu\n", mas_mn(mas), i,
 				piv, mas->min);
-			MT_BUG_ON(mas->tree, piv < mas->min);
+			MAS_WARN_ON(mas, piv < mas->min);
 		}
 		if (piv > mas->max) {
 			pr_err("%p[%u] %lu > %lu\n", mas_mn(mas), i,
 				piv, mas->max);
-			MT_BUG_ON(mas->tree, piv > mas->max);
+			MAS_WARN_ON(mas, piv > mas->max);
 		}
 		prev_piv = piv;
 		if (piv == mas->max)
@@ -7135,7 +7148,7 @@ static void mas_validate_limits(struct ma_state *mas)
 
 			pr_err("%p[%u] should not have piv %lu\n",
 			       mas_mn(mas), i, piv);
-			MT_BUG_ON(mas->tree, i < mt_pivots[type] - 1);
+			MAS_WARN_ON(mas, i < mt_pivots[type] - 1);
 		}
 	}
 }
@@ -7194,16 +7207,15 @@ void mt_validate(struct maple_tree *mt)
 
 	mas_first_entry(&mas, mas_mn(&mas), ULONG_MAX, mte_node_type(mas.node));
 	while (!mas_is_none(&mas)) {
-		MT_BUG_ON(mas.tree, mte_dead_node(mas.node));
+		MAS_WARN_ON(&mas, mte_dead_node(mas.node));
 		if (!mte_is_root(mas.node)) {
 			end = mas_data_end(&mas);
-			if ((end < mt_min_slot_count(mas.node)) &&
-			    (mas.max != ULONG_MAX)) {
+			if (MAS_WARN_ON(&mas,
+					(end < mt_min_slot_count(mas.node)) &&
+					(mas.max != ULONG_MAX))) {
 				pr_err("Invalid size %u of %p\n", end,
-				mas_mn(&mas));
-				MT_BUG_ON(mas.tree, 1);
+				       mas_mn(&mas));
 			}
-
 		}
 		mas_validate_parent_slot(&mas);
 		mas_validate_child_slot(&mas);
@@ -7219,4 +7231,34 @@ done:
 }
 EXPORT_SYMBOL_GPL(mt_validate);
 
+void mas_dump(const struct ma_state *mas)
+{
+	pr_err("MAS: tree=%p enode=%p ", mas->tree, mas->node);
+	if (mas_is_none(mas))
+		pr_err("(MAS_NONE) ");
+	else if (mas_is_ptr(mas))
+		pr_err("(MAS_ROOT) ");
+	else if (mas_is_start(mas))
+		 pr_err("(MAS_START) ");
+	else if (mas_is_paused(mas))
+		pr_err("(MAS_PAUSED) ");
+
+	pr_err("[%u] index=%lx last=%lx\n", mas->offset, mas->index, mas->last);
+	pr_err("     min=%lx max=%lx alloc=%p, depth=%u, flags=%x\n",
+	       mas->min, mas->max, mas->alloc, mas->depth, mas->mas_flags);
+	if (mas->index > mas->last)
+		pr_err("Check index & last\n");
+}
+EXPORT_SYMBOL_GPL(mas_dump);
+
+void mas_wr_dump(const struct ma_wr_state *wr_mas)
+{
+	pr_err("WR_MAS: node=%p r_min=%lx r_max=%lx\n",
+	       wr_mas->node, wr_mas->r_min, wr_mas->r_max);
+	pr_err("        type=%u off_end=%u, node_end=%u, end_piv=%lx\n",
+	       wr_mas->type, wr_mas->offset_end, wr_mas->node_end,
+	       wr_mas->end_piv);
+}
+EXPORT_SYMBOL_GPL(mas_wr_dump);
+
 #endif /* CONFIG_DEBUG_MAPLE_TREE */
diff --git a/lib/show_mem.c b/lib/show_mem.c
deleted file mode 100644
index 1485c87be935..000000000000
--- a/lib/show_mem.c
+++ /dev/null
@@ -1,37 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * Generic show_mem() implementation
- *
- * Copyright (C) 2008 Johannes Weiner <hannes@saeurebad.de>
- */
-
-#include <linux/mm.h>
-#include <linux/cma.h>
-
-void __show_mem(unsigned int filter, nodemask_t *nodemask, int max_zone_idx)
-{
-	unsigned long total = 0, reserved = 0, highmem = 0;
-	struct zone *zone;
-
-	printk("Mem-Info:\n");
-	__show_free_areas(filter, nodemask, max_zone_idx);
-
-	for_each_populated_zone(zone) {
-
-		total += zone->present_pages;
-		reserved += zone->present_pages - zone_managed_pages(zone);
-
-		if (is_highmem(zone))
-			highmem += zone->present_pages;
-	}
-
-	printk("%lu pages RAM\n", total);
-	printk("%lu pages HighMem/MovableOnly\n", highmem);
-	printk("%lu pages reserved\n", reserved);
-#ifdef CONFIG_CMA
-	printk("%lu pages cma reserved\n", totalcma_pages);
-#endif
-#ifdef CONFIG_MEMORY_FAILURE
-	printk("%lu pages hwpoisoned\n", atomic_long_read(&num_poisoned_pages));
-#endif
-}
diff --git a/lib/test_maple_tree.c b/lib/test_maple_tree.c
index f1db333270e9..9939be34e516 100644
--- a/lib/test_maple_tree.c
+++ b/lib/test_maple_tree.c
@@ -11,12 +11,33 @@
 #include <linux/module.h>
 
 #define MTREE_ALLOC_MAX 0x2000000000000Ul
-#ifndef CONFIG_DEBUG_MAPLE_TREE
-#define CONFIG_DEBUG_MAPLE_TREE
-#endif
 #define CONFIG_MAPLE_SEARCH
 #define MAPLE_32BIT (MAPLE_NODE_SLOTS > 31)
 
+#ifndef CONFIG_DEBUG_MAPLE_TREE
+#define mt_dump(mt, fmt)		do {} while (0)
+#define mt_validate(mt)			do {} while (0)
+#define mt_cache_shrink()		do {} while (0)
+#define mas_dump(mas)			do {} while (0)
+#define mas_wr_dump(mas)		do {} while (0)
+atomic_t maple_tree_tests_run;
+atomic_t maple_tree_tests_passed;
+#undef MT_BUG_ON
+
+#define MT_BUG_ON(__tree, __x) do {					\
+	atomic_inc(&maple_tree_tests_run);				\
+	if (__x) {							\
+		pr_info("BUG at %s:%d (%u)\n",				\
+		__func__, __LINE__, __x);				\
+		pr_info("Pass: %u Run:%u\n",				\
+			atomic_read(&maple_tree_tests_passed),		\
+			atomic_read(&maple_tree_tests_run));		\
+	} else {							\
+		atomic_inc(&maple_tree_tests_passed);			\
+	}								\
+} while (0)
+#endif
+
 /* #define BENCH_SLOT_STORE */
 /* #define BENCH_NODE_STORE */
 /* #define BENCH_AWALK */
@@ -30,54 +51,54 @@
 #else
 #define cond_resched()			do {} while (0)
 #endif
-static
-int mtree_insert_index(struct maple_tree *mt, unsigned long index, gfp_t gfp)
+static int __init mtree_insert_index(struct maple_tree *mt,
+				     unsigned long index, gfp_t gfp)
 {
 	return mtree_insert(mt, index, xa_mk_value(index & LONG_MAX), gfp);
 }
 
-static void mtree_erase_index(struct maple_tree *mt, unsigned long index)
+static void __init mtree_erase_index(struct maple_tree *mt, unsigned long index)
 {
 	MT_BUG_ON(mt, mtree_erase(mt, index) != xa_mk_value(index & LONG_MAX));
 	MT_BUG_ON(mt, mtree_load(mt, index) != NULL);
 }
 
-static int mtree_test_insert(struct maple_tree *mt, unsigned long index,
+static int __init mtree_test_insert(struct maple_tree *mt, unsigned long index,
 				void *ptr)
 {
 	return mtree_insert(mt, index, ptr, GFP_KERNEL);
 }
 
-static int mtree_test_store_range(struct maple_tree *mt, unsigned long start,
-				unsigned long end, void *ptr)
+static int __init mtree_test_store_range(struct maple_tree *mt,
+			unsigned long start, unsigned long end, void *ptr)
 {
 	return mtree_store_range(mt, start, end, ptr, GFP_KERNEL);
 }
 
-static int mtree_test_store(struct maple_tree *mt, unsigned long start,
+static int __init mtree_test_store(struct maple_tree *mt, unsigned long start,
 				void *ptr)
 {
 	return mtree_test_store_range(mt, start, start, ptr);
 }
 
-static int mtree_test_insert_range(struct maple_tree *mt, unsigned long start,
-				unsigned long end, void *ptr)
+static int __init mtree_test_insert_range(struct maple_tree *mt,
+			unsigned long start, unsigned long end, void *ptr)
 {
 	return mtree_insert_range(mt, start, end, ptr, GFP_KERNEL);
 }
 
-static void *mtree_test_load(struct maple_tree *mt, unsigned long index)
+static void __init *mtree_test_load(struct maple_tree *mt, unsigned long index)
 {
 	return mtree_load(mt, index);
 }
 
-static void *mtree_test_erase(struct maple_tree *mt, unsigned long index)
+static void __init *mtree_test_erase(struct maple_tree *mt, unsigned long index)
 {
 	return mtree_erase(mt, index);
 }
 
 #if defined(CONFIG_64BIT)
-static noinline void check_mtree_alloc_range(struct maple_tree *mt,
+static noinline void __init check_mtree_alloc_range(struct maple_tree *mt,
 		unsigned long start, unsigned long end, unsigned long size,
 		unsigned long expected, int eret, void *ptr)
 {
@@ -94,7 +115,7 @@ static noinline void check_mtree_alloc_range(struct maple_tree *mt,
 	MT_BUG_ON(mt, result != expected);
 }
 
-static noinline void check_mtree_alloc_rrange(struct maple_tree *mt,
+static noinline void __init check_mtree_alloc_rrange(struct maple_tree *mt,
 		unsigned long start, unsigned long end, unsigned long size,
 		unsigned long expected, int eret, void *ptr)
 {
@@ -102,7 +123,7 @@ static noinline void check_mtree_alloc_rrange(struct maple_tree *mt,
 	unsigned long result = expected + 1;
 	int ret;
 
-	ret = mtree_alloc_rrange(mt, &result, ptr, size, start, end - 1,
+	ret = mtree_alloc_rrange(mt, &result, ptr, size, start, end,
 			GFP_KERNEL);
 	MT_BUG_ON(mt, ret != eret);
 	if (ret)
@@ -112,8 +133,8 @@ static noinline void check_mtree_alloc_rrange(struct maple_tree *mt,
 }
 #endif
 
-static noinline void check_load(struct maple_tree *mt, unsigned long index,
-				void *ptr)
+static noinline void __init check_load(struct maple_tree *mt,
+				       unsigned long index, void *ptr)
 {
 	void *ret = mtree_test_load(mt, index);
 
@@ -122,7 +143,7 @@ static noinline void check_load(struct maple_tree *mt, unsigned long index,
 	MT_BUG_ON(mt, ret != ptr);
 }
 
-static noinline void check_store_range(struct maple_tree *mt,
+static noinline void __init check_store_range(struct maple_tree *mt,
 		unsigned long start, unsigned long end, void *ptr, int expected)
 {
 	int ret = -EINVAL;
@@ -138,7 +159,7 @@ static noinline void check_store_range(struct maple_tree *mt,
 		check_load(mt, i, ptr);
 }
 
-static noinline void check_insert_range(struct maple_tree *mt,
+static noinline void __init check_insert_range(struct maple_tree *mt,
 		unsigned long start, unsigned long end, void *ptr, int expected)
 {
 	int ret = -EINVAL;
@@ -154,8 +175,8 @@ static noinline void check_insert_range(struct maple_tree *mt,
 		check_load(mt, i, ptr);
 }
 
-static noinline void check_insert(struct maple_tree *mt, unsigned long index,
-		void *ptr)
+static noinline void __init check_insert(struct maple_tree *mt,
+					 unsigned long index, void *ptr)
 {
 	int ret = -EINVAL;
 
@@ -163,7 +184,7 @@ static noinline void check_insert(struct maple_tree *mt, unsigned long index,
 	MT_BUG_ON(mt, ret != 0);
 }
 
-static noinline void check_dup_insert(struct maple_tree *mt,
+static noinline void __init check_dup_insert(struct maple_tree *mt,
 				      unsigned long index, void *ptr)
 {
 	int ret = -EINVAL;
@@ -173,13 +194,13 @@ static noinline void check_dup_insert(struct maple_tree *mt,
 }
 
 
-static noinline
-void check_index_load(struct maple_tree *mt, unsigned long index)
+static noinline void __init check_index_load(struct maple_tree *mt,
+					     unsigned long index)
 {
 	return check_load(mt, index, xa_mk_value(index & LONG_MAX));
 }
 
-static inline int not_empty(struct maple_node *node)
+static inline __init int not_empty(struct maple_node *node)
 {
 	int i;
 
@@ -194,8 +215,8 @@ static inline int not_empty(struct maple_node *node)
 }
 
 
-static noinline void check_rev_seq(struct maple_tree *mt, unsigned long max,
-		bool verbose)
+static noinline void __init check_rev_seq(struct maple_tree *mt,
+					  unsigned long max, bool verbose)
 {
 	unsigned long i = max, j;
 
@@ -219,7 +240,7 @@ static noinline void check_rev_seq(struct maple_tree *mt, unsigned long max,
 #ifndef __KERNEL__
 	if (verbose) {
 		rcu_barrier();
-		mt_dump(mt);
+		mt_dump(mt, mt_dump_dec);
 		pr_info(" %s test of 0-%lu %luK in %d active (%d total)\n",
 			__func__, max, mt_get_alloc_size()/1024, mt_nr_allocated(),
 			mt_nr_tallocated());
@@ -227,7 +248,7 @@ static noinline void check_rev_seq(struct maple_tree *mt, unsigned long max,
 #endif
 }
 
-static noinline void check_seq(struct maple_tree *mt, unsigned long max,
+static noinline void __init check_seq(struct maple_tree *mt, unsigned long max,
 		bool verbose)
 {
 	unsigned long i, j;
@@ -248,7 +269,7 @@ static noinline void check_seq(struct maple_tree *mt, unsigned long max,
 #ifndef __KERNEL__
 	if (verbose) {
 		rcu_barrier();
-		mt_dump(mt);
+		mt_dump(mt, mt_dump_dec);
 		pr_info(" seq test of 0-%lu %luK in %d active (%d total)\n",
 			max, mt_get_alloc_size()/1024, mt_nr_allocated(),
 			mt_nr_tallocated());
@@ -256,7 +277,7 @@ static noinline void check_seq(struct maple_tree *mt, unsigned long max,
 #endif
 }
 
-static noinline void check_lb_not_empty(struct maple_tree *mt)
+static noinline void __init check_lb_not_empty(struct maple_tree *mt)
 {
 	unsigned long i, j;
 	unsigned long huge = 4000UL * 1000 * 1000;
@@ -275,13 +296,13 @@ static noinline void check_lb_not_empty(struct maple_tree *mt)
 	mtree_destroy(mt);
 }
 
-static noinline void check_lower_bound_split(struct maple_tree *mt)
+static noinline void __init check_lower_bound_split(struct maple_tree *mt)
 {
 	MT_BUG_ON(mt, !mtree_empty(mt));
 	check_lb_not_empty(mt);
 }
 
-static noinline void check_upper_bound_split(struct maple_tree *mt)
+static noinline void __init check_upper_bound_split(struct maple_tree *mt)
 {
 	unsigned long i, j;
 	unsigned long huge;
@@ -306,7 +327,7 @@ static noinline void check_upper_bound_split(struct maple_tree *mt)
 	mtree_destroy(mt);
 }
 
-static noinline void check_mid_split(struct maple_tree *mt)
+static noinline void __init check_mid_split(struct maple_tree *mt)
 {
 	unsigned long huge = 8000UL * 1000 * 1000;
 
@@ -315,7 +336,7 @@ static noinline void check_mid_split(struct maple_tree *mt)
 	check_lb_not_empty(mt);
 }
 
-static noinline void check_rev_find(struct maple_tree *mt)
+static noinline void __init check_rev_find(struct maple_tree *mt)
 {
 	int i, nr_entries = 200;
 	void *val;
@@ -354,7 +375,7 @@ static noinline void check_rev_find(struct maple_tree *mt)
 	rcu_read_unlock();
 }
 
-static noinline void check_find(struct maple_tree *mt)
+static noinline void __init check_find(struct maple_tree *mt)
 {
 	unsigned long val = 0;
 	unsigned long count;
@@ -571,7 +592,7 @@ static noinline void check_find(struct maple_tree *mt)
 	mtree_destroy(mt);
 }
 
-static noinline void check_find_2(struct maple_tree *mt)
+static noinline void __init check_find_2(struct maple_tree *mt)
 {
 	unsigned long i, j;
 	void *entry;
@@ -616,7 +637,7 @@ static noinline void check_find_2(struct maple_tree *mt)
 
 
 #if defined(CONFIG_64BIT)
-static noinline void check_alloc_rev_range(struct maple_tree *mt)
+static noinline void __init check_alloc_rev_range(struct maple_tree *mt)
 {
 	/*
 	 * Generated by:
@@ -624,7 +645,7 @@ static noinline void check_alloc_rev_range(struct maple_tree *mt)
 	 * awk -F "-" '{printf "0x%s, 0x%s, ", $1, $2}'
 	 */
 
-	unsigned long range[] = {
+	static const unsigned long range[] = {
 	/*      Inclusive     , Exclusive. */
 		0x565234af2000, 0x565234af4000,
 		0x565234af4000, 0x565234af9000,
@@ -652,7 +673,7 @@ static noinline void check_alloc_rev_range(struct maple_tree *mt)
 		0x7fff58791000, 0x7fff58793000,
 	};
 
-	unsigned long holes[] = {
+	static const unsigned long holes[] = {
 		/*
 		 * Note: start of hole is INCLUSIVE
 		 *        end of hole is EXCLUSIVE
@@ -672,7 +693,7 @@ static noinline void check_alloc_rev_range(struct maple_tree *mt)
 	 * 4. number that should be returned.
 	 * 5. return value
 	 */
-	unsigned long req_range[] = {
+	static const unsigned long req_range[] = {
 		0x565234af9000, /* Min */
 		0x7fff58791000, /* Max */
 		0x1000,         /* Size */
@@ -680,7 +701,7 @@ static noinline void check_alloc_rev_range(struct maple_tree *mt)
 		0,              /* Return value success. */
 
 		0x0,            /* Min */
-		0x565234AF1 << 12,    /* Max */
+		0x565234AF0 << 12,    /* Max */
 		0x3000,         /* Size */
 		0x565234AEE << 12,  /* max - 3. */
 		0,              /* Return value success. */
@@ -692,14 +713,14 @@ static noinline void check_alloc_rev_range(struct maple_tree *mt)
 		0,              /* Return value success. */
 
 		0x0,            /* Min */
-		0x7F36D510A << 12,    /* Max */
+		0x7F36D5109 << 12,    /* Max */
 		0x4000,         /* Size */
 		0x7F36D5106 << 12,    /* First rev hole of size 0x4000 */
 		0,              /* Return value success. */
 
 		/* Ascend test. */
 		0x0,
-		34148798629 << 12,
+		34148798628 << 12,
 		19 << 12,
 		34148797418 << 12,
 		0x0,
@@ -711,6 +732,12 @@ static noinline void check_alloc_rev_range(struct maple_tree *mt)
 		0x0,
 		-EBUSY,
 
+		/* Single space test. */
+		34148798725 << 12,
+		34148798725 << 12,
+		1 << 12,
+		34148798725 << 12,
+		0,
 	};
 
 	int i, range_count = ARRAY_SIZE(range);
@@ -759,9 +786,9 @@ static noinline void check_alloc_rev_range(struct maple_tree *mt)
 	mas_unlock(&mas);
 	for (i = 0; i < req_range_count; i += 5) {
 #if DEBUG_REV_RANGE
-		pr_debug("\tReverse request between %lu-%lu size %lu, should get %lu\n",
-				req_range[i] >> 12,
-				(req_range[i + 1] >> 12) - 1,
+		pr_debug("\tReverse request %d between %lu-%lu size %lu, should get %lu\n",
+				i, req_range[i] >> 12,
+				(req_range[i + 1] >> 12),
 				req_range[i+2] >> 12,
 				req_range[i+3] >> 12);
 #endif
@@ -777,13 +804,14 @@ static noinline void check_alloc_rev_range(struct maple_tree *mt)
 
 	mt_set_non_kernel(1);
 	mtree_erase(mt, 34148798727); /* create a deleted range. */
+	mtree_erase(mt, 34148798725);
 	check_mtree_alloc_rrange(mt, 0, 34359052173, 210253414,
 			34148798725, 0, mt);
 
 	mtree_destroy(mt);
 }
 
-static noinline void check_alloc_range(struct maple_tree *mt)
+static noinline void __init check_alloc_range(struct maple_tree *mt)
 {
 	/*
 	 * Generated by:
@@ -791,7 +819,7 @@ static noinline void check_alloc_range(struct maple_tree *mt)
 	 * awk -F "-" '{printf "0x%s, 0x%s, ", $1, $2}'
 	 */
 
-	unsigned long range[] = {
+	static const unsigned long range[] = {
 	/*      Inclusive     , Exclusive. */
 		0x565234af2000, 0x565234af4000,
 		0x565234af4000, 0x565234af9000,
@@ -818,7 +846,7 @@ static noinline void check_alloc_range(struct maple_tree *mt)
 		0x7fff5878e000, 0x7fff58791000,
 		0x7fff58791000, 0x7fff58793000,
 	};
-	unsigned long holes[] = {
+	static const unsigned long holes[] = {
 		/* Start of hole, end of hole,  size of hole (+1) */
 		0x565234afb000, 0x565234afc000, 0x1000,
 		0x565234afe000, 0x565235def000, 0x12F1000,
@@ -833,7 +861,7 @@ static noinline void check_alloc_range(struct maple_tree *mt)
 	 * 4. number that should be returned.
 	 * 5. return value
 	 */
-	unsigned long req_range[] = {
+	static const unsigned long req_range[] = {
 		0x565234af9000, /* Min */
 		0x7fff58791000, /* Max */
 		0x1000,         /* Size */
@@ -880,6 +908,13 @@ static noinline void check_alloc_range(struct maple_tree *mt)
 		4503599618982063UL << 12,  /* Size */
 		34359052178 << 12,  /* Expected location */
 		-EBUSY,             /* Return failure. */
+
+		/* Test a single entry */
+		34148798648 << 12,		/* Min */
+		34148798648 << 12,		/* Max */
+		4096,			/* Size of 1 */
+		34148798648 << 12,	/* Location is the same as min/max */
+		0,			/* Success */
 	};
 	int i, range_count = ARRAY_SIZE(range);
 	int req_range_count = ARRAY_SIZE(req_range);
@@ -893,7 +928,7 @@ static noinline void check_alloc_range(struct maple_tree *mt)
 #if DEBUG_ALLOC_RANGE
 		pr_debug("\tInsert %lu-%lu\n", range[i] >> 12,
 			 (range[i + 1] >> 12) - 1);
-		mt_dump(mt);
+		mt_dump(mt, mt_dump_hex);
 #endif
 		check_insert_range(mt, range[i] >> 12, (range[i + 1] >> 12) - 1,
 				xa_mk_value(range[i] >> 12), 0);
@@ -934,7 +969,7 @@ static noinline void check_alloc_range(struct maple_tree *mt)
 				xa_mk_value(req_range[i] >> 12)); /* pointer */
 		mt_validate(mt);
 #if DEBUG_ALLOC_RANGE
-		mt_dump(mt);
+		mt_dump(mt, mt_dump_hex);
 #endif
 	}
 
@@ -942,10 +977,10 @@ static noinline void check_alloc_range(struct maple_tree *mt)
 }
 #endif
 
-static noinline void check_ranges(struct maple_tree *mt)
+static noinline void __init check_ranges(struct maple_tree *mt)
 {
 	int i, val, val2;
-	unsigned long r[] = {
+	static const unsigned long r[] = {
 		10, 15,
 		20, 25,
 		17, 22, /* Overlaps previous range. */
@@ -1210,7 +1245,7 @@ static noinline void check_ranges(struct maple_tree *mt)
 		MT_BUG_ON(mt, mt_height(mt) != 4);
 }
 
-static noinline void check_next_entry(struct maple_tree *mt)
+static noinline void __init check_next_entry(struct maple_tree *mt)
 {
 	void *entry = NULL;
 	unsigned long limit = 30, i = 0;
@@ -1234,7 +1269,7 @@ static noinline void check_next_entry(struct maple_tree *mt)
 	mtree_destroy(mt);
 }
 
-static noinline void check_prev_entry(struct maple_tree *mt)
+static noinline void __init check_prev_entry(struct maple_tree *mt)
 {
 	unsigned long index = 16;
 	void *value;
@@ -1278,7 +1313,7 @@ static noinline void check_prev_entry(struct maple_tree *mt)
 	mas_unlock(&mas);
 }
 
-static noinline void check_root_expand(struct maple_tree *mt)
+static noinline void __init check_root_expand(struct maple_tree *mt)
 {
 	MA_STATE(mas, mt, 0, 0);
 	void *ptr;
@@ -1287,6 +1322,7 @@ static noinline void check_root_expand(struct maple_tree *mt)
 	mas_lock(&mas);
 	mas_set(&mas, 3);
 	ptr = mas_walk(&mas);
+	MT_BUG_ON(mt, mas.index != 0);
 	MT_BUG_ON(mt, ptr != NULL);
 	MT_BUG_ON(mt, mas.index != 0);
 	MT_BUG_ON(mt, mas.last != ULONG_MAX);
@@ -1356,7 +1392,7 @@ static noinline void check_root_expand(struct maple_tree *mt)
 	mas_store_gfp(&mas, ptr, GFP_KERNEL);
 	ptr = mas_next(&mas, ULONG_MAX);
 	MT_BUG_ON(mt, ptr != NULL);
-	MT_BUG_ON(mt, (mas.index != 1) && (mas.last != ULONG_MAX));
+	MT_BUG_ON(mt, (mas.index != ULONG_MAX) && (mas.last != ULONG_MAX));
 
 	mas_set(&mas, 1);
 	ptr = mas_prev(&mas, 0);
@@ -1367,13 +1403,13 @@ static noinline void check_root_expand(struct maple_tree *mt)
 	mas_unlock(&mas);
 }
 
-static noinline void check_gap_combining(struct maple_tree *mt)
+static noinline void __init check_gap_combining(struct maple_tree *mt)
 {
 	struct maple_enode *mn1, *mn2;
 	void *entry;
 	unsigned long singletons = 100;
-	unsigned long *seq100;
-	unsigned long seq100_64[] = {
+	static const unsigned long *seq100;
+	static const unsigned long seq100_64[] = {
 		/* 0-5 */
 		74, 75, 76,
 		50, 100, 2,
@@ -1387,7 +1423,7 @@ static noinline void check_gap_combining(struct maple_tree *mt)
 		76, 2, 79, 85, 4,
 	};
 
-	unsigned long seq100_32[] = {
+	static const unsigned long seq100_32[] = {
 		/* 0-5 */
 		61, 62, 63,
 		50, 100, 2,
@@ -1401,11 +1437,11 @@ static noinline void check_gap_combining(struct maple_tree *mt)
 		76, 2, 79, 85, 4,
 	};
 
-	unsigned long seq2000[] = {
+	static const unsigned long seq2000[] = {
 		1152, 1151,
 		1100, 1200, 2,
 	};
-	unsigned long seq400[] = {
+	static const unsigned long seq400[] = {
 		286, 318,
 		256, 260, 266, 270, 275, 280, 290, 398,
 		286, 310,
@@ -1564,7 +1600,7 @@ static noinline void check_gap_combining(struct maple_tree *mt)
 	mt_set_non_kernel(0);
 	mtree_destroy(mt);
 }
-static noinline void check_node_overwrite(struct maple_tree *mt)
+static noinline void __init check_node_overwrite(struct maple_tree *mt)
 {
 	int i, max = 4000;
 
@@ -1572,12 +1608,12 @@ static noinline void check_node_overwrite(struct maple_tree *mt)
 		mtree_test_store_range(mt, i*100, i*100 + 50, xa_mk_value(i*100));
 
 	mtree_test_store_range(mt, 319951, 367950, NULL);
-	/*mt_dump(mt); */
+	/*mt_dump(mt, mt_dump_dec); */
 	mt_validate(mt);
 }
 
 #if defined(BENCH_SLOT_STORE)
-static noinline void bench_slot_store(struct maple_tree *mt)
+static noinline void __init bench_slot_store(struct maple_tree *mt)
 {
 	int i, brk = 105, max = 1040, brk_start = 100, count = 20000000;
 
@@ -1593,7 +1629,7 @@ static noinline void bench_slot_store(struct maple_tree *mt)
 #endif
 
 #if defined(BENCH_NODE_STORE)
-static noinline void bench_node_store(struct maple_tree *mt)
+static noinline void __init bench_node_store(struct maple_tree *mt)
 {
 	int i, overwrite = 76, max = 240, count = 20000000;
 
@@ -1612,7 +1648,7 @@ static noinline void bench_node_store(struct maple_tree *mt)
 #endif
 
 #if defined(BENCH_AWALK)
-static noinline void bench_awalk(struct maple_tree *mt)
+static noinline void __init bench_awalk(struct maple_tree *mt)
 {
 	int i, max = 2500, count = 50000000;
 	MA_STATE(mas, mt, 1470, 1470);
@@ -1629,7 +1665,7 @@ static noinline void bench_awalk(struct maple_tree *mt)
 }
 #endif
 #if defined(BENCH_WALK)
-static noinline void bench_walk(struct maple_tree *mt)
+static noinline void __init bench_walk(struct maple_tree *mt)
 {
 	int i, max = 2500, count = 550000000;
 	MA_STATE(mas, mt, 1470, 1470);
@@ -1646,7 +1682,7 @@ static noinline void bench_walk(struct maple_tree *mt)
 #endif
 
 #if defined(BENCH_MT_FOR_EACH)
-static noinline void bench_mt_for_each(struct maple_tree *mt)
+static noinline void __init bench_mt_for_each(struct maple_tree *mt)
 {
 	int i, count = 1000000;
 	unsigned long max = 2500, index = 0;
@@ -1670,7 +1706,7 @@ static noinline void bench_mt_for_each(struct maple_tree *mt)
 #endif
 
 /* check_forking - simulate the kernel forking sequence with the tree. */
-static noinline void check_forking(struct maple_tree *mt)
+static noinline void __init check_forking(struct maple_tree *mt)
 {
 
 	struct maple_tree newmt;
@@ -1709,7 +1745,7 @@ static noinline void check_forking(struct maple_tree *mt)
 	mtree_destroy(&newmt);
 }
 
-static noinline void check_iteration(struct maple_tree *mt)
+static noinline void __init check_iteration(struct maple_tree *mt)
 {
 	int i, nr_entries = 125;
 	void *val;
@@ -1765,7 +1801,6 @@ static noinline void check_iteration(struct maple_tree *mt)
 			mas.index = 760;
 			mas.last = 765;
 			mas_store(&mas, val);
-			mas_next(&mas, ULONG_MAX);
 		}
 		i++;
 	}
@@ -1777,7 +1812,7 @@ static noinline void check_iteration(struct maple_tree *mt)
 	mt_set_non_kernel(0);
 }
 
-static noinline void check_mas_store_gfp(struct maple_tree *mt)
+static noinline void __init check_mas_store_gfp(struct maple_tree *mt)
 {
 
 	struct maple_tree newmt;
@@ -1810,7 +1845,7 @@ static noinline void check_mas_store_gfp(struct maple_tree *mt)
 }
 
 #if defined(BENCH_FORK)
-static noinline void bench_forking(struct maple_tree *mt)
+static noinline void __init bench_forking(struct maple_tree *mt)
 {
 
 	struct maple_tree newmt;
@@ -1852,15 +1887,17 @@ static noinline void bench_forking(struct maple_tree *mt)
 }
 #endif
 
-static noinline void next_prev_test(struct maple_tree *mt)
+static noinline void __init next_prev_test(struct maple_tree *mt)
 {
 	int i, nr_entries;
 	void *val;
 	MA_STATE(mas, mt, 0, 0);
 	struct maple_enode *mn;
-	unsigned long *level2;
-	unsigned long level2_64[] = {707, 1000, 710, 715, 720, 725};
-	unsigned long level2_32[] = {1747, 2000, 1750, 1755, 1760, 1765};
+	static const unsigned long *level2;
+	static const unsigned long level2_64[] = { 707, 1000, 710, 715, 720,
+						   725};
+	static const unsigned long level2_32[] = { 1747, 2000, 1750, 1755,
+						   1760, 1765};
 
 	if (MAPLE_32BIT) {
 		nr_entries = 500;
@@ -1974,7 +2011,7 @@ static noinline void next_prev_test(struct maple_tree *mt)
 
 	val = mas_next(&mas, ULONG_MAX);
 	MT_BUG_ON(mt, val != NULL);
-	MT_BUG_ON(mt, mas.index != ULONG_MAX);
+	MT_BUG_ON(mt, mas.index != 0x7d6);
 	MT_BUG_ON(mt, mas.last != ULONG_MAX);
 
 	val = mas_prev(&mas, 0);
@@ -1998,7 +2035,8 @@ static noinline void next_prev_test(struct maple_tree *mt)
 	val = mas_prev(&mas, 0);
 	MT_BUG_ON(mt, val != NULL);
 	MT_BUG_ON(mt, mas.index != 0);
-	MT_BUG_ON(mt, mas.last != 0);
+	MT_BUG_ON(mt, mas.last != 5);
+	MT_BUG_ON(mt, mas.node != MAS_NONE);
 
 	mas.index = 0;
 	mas.last = 5;
@@ -2010,7 +2048,7 @@ static noinline void next_prev_test(struct maple_tree *mt)
 	val = mas_prev(&mas, 0);
 	MT_BUG_ON(mt, val != NULL);
 	MT_BUG_ON(mt, mas.index != 0);
-	MT_BUG_ON(mt, mas.last != 0);
+	MT_BUG_ON(mt, mas.last != 9);
 	mas_unlock(&mas);
 
 	mtree_destroy(mt);
@@ -2028,7 +2066,7 @@ static noinline void next_prev_test(struct maple_tree *mt)
 
 
 /* Test spanning writes that require balancing right sibling or right cousin */
-static noinline void check_spanning_relatives(struct maple_tree *mt)
+static noinline void __init check_spanning_relatives(struct maple_tree *mt)
 {
 
 	unsigned long i, nr_entries = 1000;
@@ -2041,7 +2079,7 @@ static noinline void check_spanning_relatives(struct maple_tree *mt)
 	mtree_store_range(mt, 9365, 9955, NULL, GFP_KERNEL);
 }
 
-static noinline void check_fuzzer(struct maple_tree *mt)
+static noinline void __init check_fuzzer(struct maple_tree *mt)
 {
 	/*
 	 * 1. Causes a spanning rebalance of a single root node.
@@ -2438,7 +2476,7 @@ static noinline void check_fuzzer(struct maple_tree *mt)
 }
 
 /* duplicate the tree with a specific gap */
-static noinline void check_dup_gaps(struct maple_tree *mt,
+static noinline void __init check_dup_gaps(struct maple_tree *mt,
 				    unsigned long nr_entries, bool zero_start,
 				    unsigned long gap)
 {
@@ -2478,7 +2516,7 @@ static noinline void check_dup_gaps(struct maple_tree *mt,
 }
 
 /* Duplicate many sizes of trees.  Mainly to test expected entry values */
-static noinline void check_dup(struct maple_tree *mt)
+static noinline void __init check_dup(struct maple_tree *mt)
 {
 	int i;
 	int big_start = 100010;
@@ -2566,7 +2604,7 @@ static noinline void check_dup(struct maple_tree *mt)
 	}
 }
 
-static noinline void check_bnode_min_spanning(struct maple_tree *mt)
+static noinline void __init check_bnode_min_spanning(struct maple_tree *mt)
 {
 	int i = 50;
 	MA_STATE(mas, mt, 0, 0);
@@ -2585,7 +2623,7 @@ static noinline void check_bnode_min_spanning(struct maple_tree *mt)
 	mt_set_non_kernel(0);
 }
 
-static noinline void check_empty_area_window(struct maple_tree *mt)
+static noinline void __init check_empty_area_window(struct maple_tree *mt)
 {
 	unsigned long i, nr_entries = 20;
 	MA_STATE(mas, mt, 0, 0);
@@ -2660,7 +2698,7 @@ static noinline void check_empty_area_window(struct maple_tree *mt)
 	MT_BUG_ON(mt, mas_empty_area(&mas, 5, 100, 6) != -EBUSY);
 
 	mas_reset(&mas);
-	MT_BUG_ON(mt, mas_empty_area(&mas, 0, 8, 10) != -EBUSY);
+	MT_BUG_ON(mt, mas_empty_area(&mas, 0, 8, 10) != -EINVAL);
 
 	mas_reset(&mas);
 	mas_empty_area(&mas, 100, 165, 3);
@@ -2670,7 +2708,7 @@ static noinline void check_empty_area_window(struct maple_tree *mt)
 	rcu_read_unlock();
 }
 
-static noinline void check_empty_area_fill(struct maple_tree *mt)
+static noinline void __init check_empty_area_fill(struct maple_tree *mt)
 {
 	const unsigned long max = 0x25D78000;
 	unsigned long size;
@@ -2713,12 +2751,635 @@ static noinline void check_empty_area_fill(struct maple_tree *mt)
 	mt_set_non_kernel(0);
 }
 
+/*
+ * Check MAS_START, MAS_PAUSE, active (implied), and MAS_NONE transitions.
+ *
+ * The table below shows the single entry tree (0-0 pointer) and normal tree
+ * with nodes.
+ *
+ * Function	ENTRY	Start		Result		index & last
+ *     ┬          ┬       ┬               ┬                ┬
+ *     │          │       │               │                └─ the final range
+ *     │          │       │               └─ The node value after execution
+ *     │          │       └─ The node value before execution
+ *     │          └─ If the entry exists or does not exists (DNE)
+ *     └─ The function name
+ *
+ * Function	ENTRY	Start		Result		index & last
+ * mas_next()
+ *  - after last
+ *			Single entry tree at 0-0
+ *			------------------------
+ *		DNE	MAS_START	MAS_NONE	1 - oo
+ *		DNE	MAS_PAUSE	MAS_NONE	1 - oo
+ *		DNE	MAS_ROOT	MAS_NONE	1 - oo
+ *			when index = 0
+ *		DNE	MAS_NONE	MAS_ROOT	0
+ *			when index > 0
+ *		DNE	MAS_NONE	MAS_NONE	1 - oo
+ *
+ *			Normal tree
+ *			-----------
+ *		exists	MAS_START	active		range
+ *		DNE	MAS_START	active		set to last range
+ *		exists	MAS_PAUSE	active		range
+ *		DNE	MAS_PAUSE	active		set to last range
+ *		exists	MAS_NONE	active		range
+ *		exists	active		active		range
+ *		DNE	active		active		set to last range
+ *
+ * Function	ENTRY	Start		Result		index & last
+ * mas_prev()
+ * - before index
+ *			Single entry tree at 0-0
+ *			------------------------
+ *				if index > 0
+ *		exists	MAS_START	MAS_ROOT	0
+ *		exists	MAS_PAUSE	MAS_ROOT	0
+ *		exists	MAS_NONE	MAS_ROOT	0
+ *
+ *				if index == 0
+ *		DNE	MAS_START	MAS_NONE	0
+ *		DNE	MAS_PAUSE	MAS_NONE	0
+ *		DNE	MAS_NONE	MAS_NONE	0
+ *		DNE	MAS_ROOT	MAS_NONE	0
+ *
+ *			Normal tree
+ *			-----------
+ *		exists	MAS_START	active		range
+ *		DNE	MAS_START	active		set to min
+ *		exists	MAS_PAUSE	active		range
+ *		DNE	MAS_PAUSE	active		set to min
+ *		exists	MAS_NONE	active		range
+ *		DNE	MAS_NONE	MAS_NONE	set to min
+ *		any	MAS_ROOT	MAS_NONE	0
+ *		exists	active		active		range
+ *		DNE	active		active		last range
+ *
+ * Function	ENTRY	Start		Result		index & last
+ * mas_find()
+ *  - at index or next
+ *			Single entry tree at 0-0
+ *			------------------------
+ *				if index >  0
+ *		DNE	MAS_START	MAS_NONE	0
+ *		DNE	MAS_PAUSE	MAS_NONE	0
+ *		DNE	MAS_ROOT	MAS_NONE	0
+ *		DNE	MAS_NONE	MAS_NONE	0
+ *				if index ==  0
+ *		exists	MAS_START	MAS_ROOT	0
+ *		exists	MAS_PAUSE	MAS_ROOT	0
+ *		exists	MAS_NONE	MAS_ROOT	0
+ *
+ *			Normal tree
+ *			-----------
+ *		exists	MAS_START	active		range
+ *		DNE	MAS_START	active		set to max
+ *		exists	MAS_PAUSE	active		range
+ *		DNE	MAS_PAUSE	active		set to max
+ *		exists	MAS_NONE	active		range
+ *		exists	active		active		range
+ *		DNE	active		active		last range (max < last)
+ *
+ * Function	ENTRY	Start		Result		index & last
+ * mas_find_rev()
+ *  - at index or before
+ *			Single entry tree at 0-0
+ *			------------------------
+ *				if index >  0
+ *		exists	MAS_START	MAS_ROOT	0
+ *		exists	MAS_PAUSE	MAS_ROOT	0
+ *		exists	MAS_NONE	MAS_ROOT	0
+ *				if index ==  0
+ *		DNE	MAS_START	MAS_NONE	0
+ *		DNE	MAS_PAUSE	MAS_NONE	0
+ *		DNE	MAS_NONE	MAS_NONE	0
+ *		DNE	MAS_ROOT	MAS_NONE	0
+ *
+ *			Normal tree
+ *			-----------
+ *		exists	MAS_START	active		range
+ *		DNE	MAS_START	active		set to min
+ *		exists	MAS_PAUSE	active		range
+ *		DNE	MAS_PAUSE	active		set to min
+ *		exists	MAS_NONE	active		range
+ *		exists	active		active		range
+ *		DNE	active		active		last range (min > index)
+ *
+ * Function	ENTRY	Start		Result		index & last
+ * mas_walk()
+ * - Look up index
+ *			Single entry tree at 0-0
+ *			------------------------
+ *				if index >  0
+ *		DNE	MAS_START	MAS_ROOT	1 - oo
+ *		DNE	MAS_PAUSE	MAS_ROOT	1 - oo
+ *		DNE	MAS_NONE	MAS_ROOT	1 - oo
+ *		DNE	MAS_ROOT	MAS_ROOT	1 - oo
+ *				if index ==  0
+ *		exists	MAS_START	MAS_ROOT	0
+ *		exists	MAS_PAUSE	MAS_ROOT	0
+ *		exists	MAS_NONE	MAS_ROOT	0
+ *		exists	MAS_ROOT	MAS_ROOT	0
+ *
+ *			Normal tree
+ *			-----------
+ *		exists	MAS_START	active		range
+ *		DNE	MAS_START	active		range of NULL
+ *		exists	MAS_PAUSE	active		range
+ *		DNE	MAS_PAUSE	active		range of NULL
+ *		exists	MAS_NONE	active		range
+ *		DNE	MAS_NONE	active		range of NULL
+ *		exists	active		active		range
+ *		DNE	active		active		range of NULL
+ */
+
+#define mas_active(x)		(((x).node != MAS_ROOT) && \
+				 ((x).node != MAS_START) && \
+				 ((x).node != MAS_PAUSE) && \
+				 ((x).node != MAS_NONE))
+static noinline void __init check_state_handling(struct maple_tree *mt)
+{
+	MA_STATE(mas, mt, 0, 0);
+	void *entry, *ptr = (void *) 0x1234500;
+	void *ptr2 = &ptr;
+	void *ptr3 = &ptr2;
+
+	/* Check MAS_ROOT First */
+	mtree_store_range(mt, 0, 0, ptr, GFP_KERNEL);
+
+	mas_lock(&mas);
+	/* prev: Start -> none */
+	entry = mas_prev(&mas, 0);
+	MT_BUG_ON(mt, entry != NULL);
+	MT_BUG_ON(mt, mas.node != MAS_NONE);
+
+	/* prev: Start -> root */
+	mas_set(&mas, 10);
+	entry = mas_prev(&mas, 0);
+	MT_BUG_ON(mt, entry != ptr);
+	MT_BUG_ON(mt, mas.index != 0);
+	MT_BUG_ON(mt, mas.last != 0);
+	MT_BUG_ON(mt, mas.node != MAS_ROOT);
+
+	/* prev: pause -> root */
+	mas_set(&mas, 10);
+	mas_pause(&mas);
+	entry = mas_prev(&mas, 0);
+	MT_BUG_ON(mt, entry != ptr);
+	MT_BUG_ON(mt, mas.index != 0);
+	MT_BUG_ON(mt, mas.last != 0);
+	MT_BUG_ON(mt, mas.node != MAS_ROOT);
+
+	/* next: start -> none */
+	mas_set(&mas, 0);
+	entry = mas_next(&mas, ULONG_MAX);
+	MT_BUG_ON(mt, mas.index != 1);
+	MT_BUG_ON(mt, mas.last != ULONG_MAX);
+	MT_BUG_ON(mt, entry != NULL);
+	MT_BUG_ON(mt, mas.node != MAS_NONE);
+
+	/* next: start -> none */
+	mas_set(&mas, 10);
+	entry = mas_next(&mas, ULONG_MAX);
+	MT_BUG_ON(mt, mas.index != 1);
+	MT_BUG_ON(mt, mas.last != ULONG_MAX);
+	MT_BUG_ON(mt, entry != NULL);
+	MT_BUG_ON(mt, mas.node != MAS_NONE);
+
+	/* find: start -> root */
+	mas_set(&mas, 0);
+	entry = mas_find(&mas, ULONG_MAX);
+	MT_BUG_ON(mt, entry != ptr);
+	MT_BUG_ON(mt, mas.index != 0);
+	MT_BUG_ON(mt, mas.last != 0);
+	MT_BUG_ON(mt, mas.node != MAS_ROOT);
+
+	/* find: root -> none */
+	entry = mas_find(&mas, ULONG_MAX);
+	MT_BUG_ON(mt, entry != NULL);
+	MT_BUG_ON(mt, mas.index != 1);
+	MT_BUG_ON(mt, mas.last != ULONG_MAX);
+	MT_BUG_ON(mt, mas.node != MAS_NONE);
+
+	/* find: none -> none */
+	entry = mas_find(&mas, ULONG_MAX);
+	MT_BUG_ON(mt, entry != NULL);
+	MT_BUG_ON(mt, mas.index != 1);
+	MT_BUG_ON(mt, mas.last != ULONG_MAX);
+	MT_BUG_ON(mt, mas.node != MAS_NONE);
+
+	/* find: start -> none */
+	mas_set(&mas, 10);
+	entry = mas_find(&mas, ULONG_MAX);
+	MT_BUG_ON(mt, entry != NULL);
+	MT_BUG_ON(mt, mas.index != 1);
+	MT_BUG_ON(mt, mas.last != ULONG_MAX);
+	MT_BUG_ON(mt, mas.node != MAS_NONE);
+
+	/* find_rev: none -> root */
+	entry = mas_find_rev(&mas, 0);
+	MT_BUG_ON(mt, entry != ptr);
+	MT_BUG_ON(mt, mas.index != 0);
+	MT_BUG_ON(mt, mas.last != 0);
+	MT_BUG_ON(mt, mas.node != MAS_ROOT);
+
+	/* find_rev: start -> root */
+	mas_set(&mas, 0);
+	entry = mas_find_rev(&mas, 0);
+	MT_BUG_ON(mt, entry != ptr);
+	MT_BUG_ON(mt, mas.index != 0);
+	MT_BUG_ON(mt, mas.last != 0);
+	MT_BUG_ON(mt, mas.node != MAS_ROOT);
+
+	/* find_rev: root -> none */
+	entry = mas_find_rev(&mas, 0);
+	MT_BUG_ON(mt, entry != NULL);
+	MT_BUG_ON(mt, mas.index != 0);
+	MT_BUG_ON(mt, mas.last != 0);
+	MT_BUG_ON(mt, mas.node != MAS_NONE);
+
+	/* find_rev: none -> none */
+	entry = mas_find_rev(&mas, 0);
+	MT_BUG_ON(mt, entry != NULL);
+	MT_BUG_ON(mt, mas.index != 0);
+	MT_BUG_ON(mt, mas.last != 0);
+	MT_BUG_ON(mt, mas.node != MAS_NONE);
+
+	/* find_rev: start -> root */
+	mas_set(&mas, 10);
+	entry = mas_find_rev(&mas, 0);
+	MT_BUG_ON(mt, entry != ptr);
+	MT_BUG_ON(mt, mas.index != 0);
+	MT_BUG_ON(mt, mas.last != 0);
+	MT_BUG_ON(mt, mas.node != MAS_ROOT);
+
+	/* walk: start -> none */
+	mas_set(&mas, 10);
+	entry = mas_walk(&mas);
+	MT_BUG_ON(mt, entry != NULL);
+	MT_BUG_ON(mt, mas.index != 1);
+	MT_BUG_ON(mt, mas.last != ULONG_MAX);
+	MT_BUG_ON(mt, mas.node != MAS_NONE);
+
+	/* walk: pause -> none*/
+	mas_set(&mas, 10);
+	mas_pause(&mas);
+	entry = mas_walk(&mas);
+	MT_BUG_ON(mt, entry != NULL);
+	MT_BUG_ON(mt, mas.index != 1);
+	MT_BUG_ON(mt, mas.last != ULONG_MAX);
+	MT_BUG_ON(mt, mas.node != MAS_NONE);
+
+	/* walk: none -> none */
+	mas.index = mas.last = 10;
+	entry = mas_walk(&mas);
+	MT_BUG_ON(mt, entry != NULL);
+	MT_BUG_ON(mt, mas.index != 1);
+	MT_BUG_ON(mt, mas.last != ULONG_MAX);
+	MT_BUG_ON(mt, mas.node != MAS_NONE);
+
+	/* walk: none -> none */
+	entry = mas_walk(&mas);
+	MT_BUG_ON(mt, entry != NULL);
+	MT_BUG_ON(mt, mas.index != 1);
+	MT_BUG_ON(mt, mas.last != ULONG_MAX);
+	MT_BUG_ON(mt, mas.node != MAS_NONE);
+
+	/* walk: start -> root */
+	mas_set(&mas, 0);
+	entry = mas_walk(&mas);
+	MT_BUG_ON(mt, entry != ptr);
+	MT_BUG_ON(mt, mas.index != 0);
+	MT_BUG_ON(mt, mas.last != 0);
+	MT_BUG_ON(mt, mas.node != MAS_ROOT);
+
+	/* walk: pause -> root */
+	mas_set(&mas, 0);
+	mas_pause(&mas);
+	entry = mas_walk(&mas);
+	MT_BUG_ON(mt, entry != ptr);
+	MT_BUG_ON(mt, mas.index != 0);
+	MT_BUG_ON(mt, mas.last != 0);
+	MT_BUG_ON(mt, mas.node != MAS_ROOT);
+
+	/* walk: none -> root */
+	mas.node = MAS_NONE;
+	entry = mas_walk(&mas);
+	MT_BUG_ON(mt, entry != ptr);
+	MT_BUG_ON(mt, mas.index != 0);
+	MT_BUG_ON(mt, mas.last != 0);
+	MT_BUG_ON(mt, mas.node != MAS_ROOT);
+
+	/* walk: root -> root */
+	entry = mas_walk(&mas);
+	MT_BUG_ON(mt, entry != ptr);
+	MT_BUG_ON(mt, mas.index != 0);
+	MT_BUG_ON(mt, mas.last != 0);
+	MT_BUG_ON(mt, mas.node != MAS_ROOT);
+
+	/* walk: root -> none */
+	mas_set(&mas, 10);
+	entry = mas_walk(&mas);
+	MT_BUG_ON(mt, entry != NULL);
+	MT_BUG_ON(mt, mas.index != 1);
+	MT_BUG_ON(mt, mas.last != ULONG_MAX);
+	MT_BUG_ON(mt, mas.node != MAS_NONE);
+
+	/* walk: none -> root */
+	mas.index = mas.last = 0;
+	entry = mas_walk(&mas);
+	MT_BUG_ON(mt, entry != ptr);
+	MT_BUG_ON(mt, mas.index != 0);
+	MT_BUG_ON(mt, mas.last != 0);
+	MT_BUG_ON(mt, mas.node != MAS_ROOT);
+
+	mas_unlock(&mas);
+
+	/* Check when there is an actual node */
+	mtree_store_range(mt, 0, 0, NULL, GFP_KERNEL);
+	mtree_store_range(mt, 0x1000, 0x1500, ptr, GFP_KERNEL);
+	mtree_store_range(mt, 0x2000, 0x2500, ptr2, GFP_KERNEL);
+	mtree_store_range(mt, 0x3000, 0x3500, ptr3, GFP_KERNEL);
+
+	mas_lock(&mas);
+
+	/* next: start ->active */
+	mas_set(&mas, 0);
+	entry = mas_next(&mas, ULONG_MAX);
+	MT_BUG_ON(mt, entry != ptr);
+	MT_BUG_ON(mt, mas.index != 0x1000);
+	MT_BUG_ON(mt, mas.last != 0x1500);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* next: pause ->active */
+	mas_set(&mas, 0);
+	mas_pause(&mas);
+	entry = mas_next(&mas, ULONG_MAX);
+	MT_BUG_ON(mt, entry != ptr);
+	MT_BUG_ON(mt, mas.index != 0x1000);
+	MT_BUG_ON(mt, mas.last != 0x1500);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* next: none ->active */
+	mas.index = mas.last = 0;
+	mas.offset = 0;
+	mas.node = MAS_NONE;
+	entry = mas_next(&mas, ULONG_MAX);
+	MT_BUG_ON(mt, entry != ptr);
+	MT_BUG_ON(mt, mas.index != 0x1000);
+	MT_BUG_ON(mt, mas.last != 0x1500);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* next:active ->active */
+	entry = mas_next(&mas, ULONG_MAX);
+	MT_BUG_ON(mt, entry != ptr2);
+	MT_BUG_ON(mt, mas.index != 0x2000);
+	MT_BUG_ON(mt, mas.last != 0x2500);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* next:active -> active out of range*/
+	entry = mas_next(&mas, 0x2999);
+	MT_BUG_ON(mt, entry != NULL);
+	MT_BUG_ON(mt, mas.index != 0x2501);
+	MT_BUG_ON(mt, mas.last != 0x2fff);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* Continue after out of range*/
+	entry = mas_next(&mas, ULONG_MAX);
+	MT_BUG_ON(mt, entry != ptr3);
+	MT_BUG_ON(mt, mas.index != 0x3000);
+	MT_BUG_ON(mt, mas.last != 0x3500);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* next:active -> active out of range*/
+	entry = mas_next(&mas, ULONG_MAX);
+	MT_BUG_ON(mt, entry != NULL);
+	MT_BUG_ON(mt, mas.index != 0x3501);
+	MT_BUG_ON(mt, mas.last != ULONG_MAX);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* next: none -> active, skip value at location */
+	mas_set(&mas, 0);
+	entry = mas_next(&mas, ULONG_MAX);
+	mas.node = MAS_NONE;
+	mas.offset = 0;
+	entry = mas_next(&mas, ULONG_MAX);
+	MT_BUG_ON(mt, entry != ptr2);
+	MT_BUG_ON(mt, mas.index != 0x2000);
+	MT_BUG_ON(mt, mas.last != 0x2500);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* prev:active ->active */
+	entry = mas_prev(&mas, 0);
+	MT_BUG_ON(mt, entry != ptr);
+	MT_BUG_ON(mt, mas.index != 0x1000);
+	MT_BUG_ON(mt, mas.last != 0x1500);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* prev:active -> active out of range*/
+	entry = mas_prev(&mas, 0);
+	MT_BUG_ON(mt, entry != NULL);
+	MT_BUG_ON(mt, mas.index != 0);
+	MT_BUG_ON(mt, mas.last != 0x0FFF);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* prev: pause ->active */
+	mas_set(&mas, 0x3600);
+	entry = mas_prev(&mas, 0);
+	MT_BUG_ON(mt, entry != ptr3);
+	mas_pause(&mas);
+	entry = mas_prev(&mas, 0);
+	MT_BUG_ON(mt, entry != ptr2);
+	MT_BUG_ON(mt, mas.index != 0x2000);
+	MT_BUG_ON(mt, mas.last != 0x2500);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* prev:active -> active out of range*/
+	entry = mas_prev(&mas, 0x1600);
+	MT_BUG_ON(mt, entry != NULL);
+	MT_BUG_ON(mt, mas.index != 0x1501);
+	MT_BUG_ON(mt, mas.last != 0x1FFF);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* prev: active ->active, continue*/
+	entry = mas_prev(&mas, 0);
+	MT_BUG_ON(mt, entry != ptr);
+	MT_BUG_ON(mt, mas.index != 0x1000);
+	MT_BUG_ON(mt, mas.last != 0x1500);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* find: start ->active */
+	mas_set(&mas, 0);
+	entry = mas_find(&mas, ULONG_MAX);
+	MT_BUG_ON(mt, entry != ptr);
+	MT_BUG_ON(mt, mas.index != 0x1000);
+	MT_BUG_ON(mt, mas.last != 0x1500);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* find: pause ->active */
+	mas_set(&mas, 0);
+	mas_pause(&mas);
+	entry = mas_find(&mas, ULONG_MAX);
+	MT_BUG_ON(mt, entry != ptr);
+	MT_BUG_ON(mt, mas.index != 0x1000);
+	MT_BUG_ON(mt, mas.last != 0x1500);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* find: start ->active on value */;
+	mas_set(&mas, 1200);
+	entry = mas_find(&mas, ULONG_MAX);
+	MT_BUG_ON(mt, entry != ptr);
+	MT_BUG_ON(mt, mas.index != 0x1000);
+	MT_BUG_ON(mt, mas.last != 0x1500);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* find:active ->active */
+	entry = mas_find(&mas, ULONG_MAX);
+	MT_BUG_ON(mt, entry != ptr2);
+	MT_BUG_ON(mt, mas.index != 0x2000);
+	MT_BUG_ON(mt, mas.last != 0x2500);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+
+	/* find:active -> active (NULL)*/
+	entry = mas_find(&mas, 0x2700);
+	MT_BUG_ON(mt, entry != NULL);
+	MT_BUG_ON(mt, mas.index != 0x2501);
+	MT_BUG_ON(mt, mas.last != 0x2FFF);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* find: none ->active */
+	entry = mas_find(&mas, 0x5000);
+	MT_BUG_ON(mt, entry != ptr3);
+	MT_BUG_ON(mt, mas.index != 0x3000);
+	MT_BUG_ON(mt, mas.last != 0x3500);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* find:active -> active (NULL) end*/
+	entry = mas_find(&mas, ULONG_MAX);
+	MT_BUG_ON(mt, entry != NULL);
+	MT_BUG_ON(mt, mas.index != 0x3501);
+	MT_BUG_ON(mt, mas.last != ULONG_MAX);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* find_rev: active (END) ->active */
+	entry = mas_find_rev(&mas, 0);
+	MT_BUG_ON(mt, entry != ptr3);
+	MT_BUG_ON(mt, mas.index != 0x3000);
+	MT_BUG_ON(mt, mas.last != 0x3500);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* find_rev:active ->active */
+	entry = mas_find_rev(&mas, 0);
+	MT_BUG_ON(mt, entry != ptr2);
+	MT_BUG_ON(mt, mas.index != 0x2000);
+	MT_BUG_ON(mt, mas.last != 0x2500);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* find_rev: pause ->active */
+	mas_pause(&mas);
+	entry = mas_find_rev(&mas, 0);
+	MT_BUG_ON(mt, entry != ptr);
+	MT_BUG_ON(mt, mas.index != 0x1000);
+	MT_BUG_ON(mt, mas.last != 0x1500);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* find_rev:active -> active */
+	entry = mas_find_rev(&mas, 0);
+	MT_BUG_ON(mt, entry != NULL);
+	MT_BUG_ON(mt, mas.index != 0);
+	MT_BUG_ON(mt, mas.last != 0x0FFF);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* find_rev: start ->active */
+	mas_set(&mas, 0x1200);
+	entry = mas_find_rev(&mas, 0);
+	MT_BUG_ON(mt, entry != ptr);
+	MT_BUG_ON(mt, mas.index != 0x1000);
+	MT_BUG_ON(mt, mas.last != 0x1500);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* mas_walk start ->active */
+	mas_set(&mas, 0x1200);
+	entry = mas_walk(&mas);
+	MT_BUG_ON(mt, entry != ptr);
+	MT_BUG_ON(mt, mas.index != 0x1000);
+	MT_BUG_ON(mt, mas.last != 0x1500);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* mas_walk start ->active */
+	mas_set(&mas, 0x1600);
+	entry = mas_walk(&mas);
+	MT_BUG_ON(mt, entry != NULL);
+	MT_BUG_ON(mt, mas.index != 0x1501);
+	MT_BUG_ON(mt, mas.last != 0x1fff);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* mas_walk pause ->active */
+	mas_set(&mas, 0x1200);
+	mas_pause(&mas);
+	entry = mas_walk(&mas);
+	MT_BUG_ON(mt, entry != ptr);
+	MT_BUG_ON(mt, mas.index != 0x1000);
+	MT_BUG_ON(mt, mas.last != 0x1500);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* mas_walk pause -> active */
+	mas_set(&mas, 0x1600);
+	mas_pause(&mas);
+	entry = mas_walk(&mas);
+	MT_BUG_ON(mt, entry != NULL);
+	MT_BUG_ON(mt, mas.index != 0x1501);
+	MT_BUG_ON(mt, mas.last != 0x1fff);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* mas_walk none -> active */
+	mas_set(&mas, 0x1200);
+	mas.node = MAS_NONE;
+	entry = mas_walk(&mas);
+	MT_BUG_ON(mt, entry != ptr);
+	MT_BUG_ON(mt, mas.index != 0x1000);
+	MT_BUG_ON(mt, mas.last != 0x1500);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* mas_walk none -> active */
+	mas_set(&mas, 0x1600);
+	mas.node = MAS_NONE;
+	entry = mas_walk(&mas);
+	MT_BUG_ON(mt, entry != NULL);
+	MT_BUG_ON(mt, mas.index != 0x1501);
+	MT_BUG_ON(mt, mas.last != 0x1fff);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* mas_walk active -> active */
+	mas.index = 0x1200;
+	mas.last = 0x1200;
+	mas.offset = 0;
+	entry = mas_walk(&mas);
+	MT_BUG_ON(mt, entry != ptr);
+	MT_BUG_ON(mt, mas.index != 0x1000);
+	MT_BUG_ON(mt, mas.last != 0x1500);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	/* mas_walk active -> active */
+	mas.index = 0x1600;
+	mas.last = 0x1600;
+	entry = mas_walk(&mas);
+	MT_BUG_ON(mt, entry != NULL);
+	MT_BUG_ON(mt, mas.index != 0x1501);
+	MT_BUG_ON(mt, mas.last != 0x1fff);
+	MT_BUG_ON(mt, !mas_active(mas));
+
+	mas_unlock(&mas);
+}
+
 static DEFINE_MTREE(tree);
-static int maple_tree_seed(void)
+static int __init maple_tree_seed(void)
 {
-	unsigned long set[] = {5015, 5014, 5017, 25, 1000,
-			       1001, 1002, 1003, 1005, 0,
-			       5003, 5002};
+	unsigned long set[] = { 5015, 5014, 5017, 25, 1000,
+				1001, 1002, 1003, 1005, 0,
+				5003, 5002};
 	void *ptr = &set;
 
 	pr_info("\nTEST STARTING\n\n");
@@ -2974,6 +3635,10 @@ static int maple_tree_seed(void)
 	mtree_destroy(&tree);
 
 
+	mt_init_flags(&tree, MT_FLAGS_ALLOC_RANGE);
+	check_state_handling(&tree);
+	mtree_destroy(&tree);
+
 #if defined(BENCH)
 skip:
 #endif
@@ -2988,7 +3653,7 @@ skip:
 	return -EINVAL;
 }
 
-static void maple_tree_harvest(void)
+static void __exit maple_tree_harvest(void)
 {
 
 }