From 86b00959fb0e3512fc42fdb4f85a7b3ecdc7fe10 Mon Sep 17 00:00:00 2001
From: "Liam R. Howlett" <Liam.Howlett@Oracle.com>
Date: Thu, 31 Oct 2019 10:45:51 -0400
Subject: [PATCH] maple_tree: Fix circular dependencies that will be created
 when mmap is modified.

This also required moving mas_retry from .h to .c to avoid xarray
include loop.

Also fix mas_restart to reset mas ranges.

Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
---
 include/linux/maple_tree.h | 36 ++++++------------------------------
 lib/maple_tree.c           | 28 ++++++++++++++++++++++++++++
 2 files changed, 34 insertions(+), 30 deletions(-)

diff --git a/include/linux/maple_tree.h b/include/linux/maple_tree.h
index 06041c4041fe..3230aaa6a7cd 100644
--- a/include/linux/maple_tree.h
+++ b/include/linux/maple_tree.h
@@ -11,8 +11,6 @@
 #include <linux/kernel.h>
 #include <linux/rcupdate.h>
 #include <linux/spinlock.h>
-#include <linux/types.h>
-#include <linux/xarray.h>
 
 /*
  * Allocated nodes are mutable until they have been inserted into the tree,
@@ -25,7 +23,7 @@
  *
  * Nodes in the tree point to their parent unless bit 0 is set.
  */
-#ifdef CONFIG_64BIT
+#if defined(CONFIG_64BIT) || defined(BUILD_VDSO32_64)
 #define MAPLE_NODE_SLOTS	15	/* 128 bytes including ->parent */
 #define MAPLE_RANGE64_SLOTS	8	/* 128 bytes */
 #define MAPLE_ARANGE64_SLOTS	5	/* 120 bytes */
@@ -317,32 +315,8 @@ void maple_tree_init(void);
 static inline void mas_reset(struct ma_state *mas)
 {
 	mas->node = MAS_START;
-}
-
-/**
- * mas_retry() - Retry the operation if appropriate.
- * @mas: Maple Tree operation state.
- * @entry: Entry from tree.
- *
- * The advanced functions may sometimes return an internal entry, such as
- * a retry entry or a zero entry.  This function sets up the @mas to restart
- * the walk from the head of the array if needed.
- *
- * Context: Any context.
- * Return: true if the operation needs to be retried.
- */
-static inline bool mas_retry(struct ma_state *mas, const void *entry)
-{
-	if (xa_is_skip(entry))
-		return true;
-	if (xa_is_deleted(entry))
-		return true;
-	if (xa_is_zero(entry))
-		return true;
-	if (!xa_is_retry(entry))
-		return false;
-	mas_reset(mas);
-	return true;
+	mas->max = ULONG_MAX;
+	mas->min = 0;
 }
 
 /**
@@ -373,6 +347,8 @@ static inline bool mas_retry(struct ma_state *mas, const void *entry)
 	for (entry = mt_find(mt, index, max); \
 	     entry; entry = mt_find_after(mt, &index, max))
 
+bool mas_retry(struct ma_state *mas, const void *entry);
+
 /**
  * mas_set_range() - Set up Maple Tree operation state for a different index.
  * @mas: Maple Tree operation state.
@@ -405,4 +381,4 @@ static inline void mas_set(struct ma_state *mas, unsigned long index)
 
 	mas_set_range(mas, index, index);
 }
-#endif
+#endif /*_LINUX_MAPLE_TREE_H */
diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index bc8f63c422c7..6b01226b90f0 100644
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -7,6 +7,8 @@
  */
 
 #include <linux/maple_tree.h>
+#include <linux/xarray.h>
+#include <linux/types.h>
 #include <linux/export.h>
 #include <linux/slab.h>
 #include <asm/barrier.h>
@@ -738,6 +740,32 @@ static inline void mas_update_limits(struct ma_state *mas, unsigned char slot,
 		mas->max = _mte_get_pivot(mas->node, slot, type);
 }
 
+/**
+ * mas_retry() - Retry the operation if appropriate.
+ * @mas: Maple Tree operation state.
+ * @entry: Entry from tree.
+ *
+ * The advanced functions may sometimes return an internal entry, such as
+ * a retry entry or a zero entry.  This function sets up the @mas to restart
+ * the walk from the head of the array if needed.
+ *
+ * Context: Any context.
+ * Return: true if the operation needs to be retried.
+ */
+bool mas_retry(struct ma_state *mas, const void *entry)
+{
+	if (xa_is_skip(entry))
+		return true;
+	if (xa_is_deleted(entry))
+		return true;
+	if (xa_is_zero(entry))
+		return true;
+	if (!xa_is_retry(entry))
+		return false;
+	mas_reset(mas);
+	return true;
+}
+
 static inline void mas_encoded_parent(struct ma_state *mas)
 {
 	struct maple_enode *p_enode, *gp_enode;
-- 
2.50.1