mm/memblock: Do some refactoring, enhance API

Refactor the memblock code and extend the memblock API to make it
more flexible. With the extended API it is simple to define and
work with additional memory lists.

The static functions memblock_add_region and __memblock_remove are
renamed to memblock_add_range and meblock_remove_range and added to
the memblock API.

The __next_free_mem_range and __next_free_mem_range_rev functions
are replaced with calls to the more generic list walkers
__next_mem_range and __next_mem_range_rev.

To walk an arbitrary memory list two new macros for_each_mem_range
and for_each_mem_range_rev are added. These new macros are used
to define for_each_free_mem_range and for_each_free_mem_range_reverse.
Signed-off-by: Philipp Hachtmann <phacht@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

include/linux/memblock.h

@@ -71,6 +71,63 @@ int memblock_reserve(phys_addr_t base, phys_addr_t size);
 void memblock_trim_memory(phys_addr_t align);
 int memblock_mark_hotplug(phys_addr_t base, phys_addr_t size);
 int memblock_clear_hotplug(phys_addr_t base, phys_addr_t size);
+
+/* Low level functions */
+int memblock_add_range(struct memblock_type *type,
+		       phys_addr_t base, phys_addr_t size,
+		       int nid, unsigned long flags);
+
+int memblock_remove_range(struct memblock_type *type,
+			  phys_addr_t base,
+			  phys_addr_t size);
+
+void __next_mem_range(u64 *idx, int nid, struct memblock_type *type_a,
+		      struct memblock_type *type_b, phys_addr_t *out_start,
+		      phys_addr_t *out_end, int *out_nid);
+
+void __next_mem_range_rev(u64 *idx, int nid, struct memblock_type *type_a,
+			  struct memblock_type *type_b, phys_addr_t *out_start,
+			  phys_addr_t *out_end, int *out_nid);
+
+/**
+ * for_each_mem_range - iterate through memblock areas from type_a and not
+ * included in type_b. Or just type_a if type_b is NULL.
+ * @i: u64 used as loop variable
+ * @type_a: ptr to memblock_type to iterate
+ * @type_b: ptr to memblock_type which excludes from the iteration
+ * @nid: node selector, %NUMA_NO_NODE for all nodes
+ * @p_start: ptr to phys_addr_t for start address of the range, can be %NULL
+ * @p_end: ptr to phys_addr_t for end address of the range, can be %NULL
+ * @p_nid: ptr to int for nid of the range, can be %NULL
+ */
+#define for_each_mem_range(i, type_a, type_b, nid,			\
+			   p_start, p_end, p_nid)			\
+	for (i = 0, __next_mem_range(&i, nid, type_a, type_b,		\
+				     p_start, p_end, p_nid);		\
+	     i != (u64)ULLONG_MAX;					\
+	     __next_mem_range(&i, nid, type_a, type_b,			\
+			      p_start, p_end, p_nid))
+
+/**
+ * for_each_mem_range_rev - reverse iterate through memblock areas from
+ * type_a and not included in type_b. Or just type_a if type_b is NULL.
+ * @i: u64 used as loop variable
+ * @type_a: ptr to memblock_type to iterate
+ * @type_b: ptr to memblock_type which excludes from the iteration
+ * @nid: node selector, %NUMA_NO_NODE for all nodes
+ * @p_start: ptr to phys_addr_t for start address of the range, can be %NULL
+ * @p_end: ptr to phys_addr_t for end address of the range, can be %NULL
+ * @p_nid: ptr to int for nid of the range, can be %NULL
+ */
+#define for_each_mem_range_rev(i, type_a, type_b, nid,			\
+			       p_start, p_end, p_nid)			\
+	for (i = (u64)ULLONG_MAX,					\
+		     __next_mem_range_rev(&i, nid, type_a, type_b,	\
+					 p_start, p_end, p_nid);	\
+	     i != (u64)ULLONG_MAX;					\
+	     __next_mem_range_rev(&i, nid, type_a, type_b,		\
+				  p_start, p_end, p_nid))
+
 #ifdef CONFIG_MOVABLE_NODE
 static inline bool memblock_is_hotpluggable(struct memblock_region *m)
 {
@@ -113,9 +170,6 @@ void __next_mem_pfn_range(int *idx, int nid, unsigned long *out_start_pfn,
 	     i >= 0; __next_mem_pfn_range(&i, nid, p_start, p_end, p_nid))
 #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
 
-void __next_free_mem_range(u64 *idx, int nid, phys_addr_t *out_start,
-			   phys_addr_t *out_end, int *out_nid);
-
 /**
  * for_each_free_mem_range - iterate through free memblock areas
  * @i: u64 used as loop variable
@@ -128,13 +182,8 @@ void __next_free_mem_range(u64 *idx, int nid, phys_addr_t *out_start,
  * soon as memblock is initialized.
  */
 #define for_each_free_mem_range(i, nid, p_start, p_end, p_nid)		\
-	for (i = 0,							\
-	     __next_free_mem_range(&i, nid, p_start, p_end, p_nid);	\
-	     i != (u64)ULLONG_MAX;					\
-	     __next_free_mem_range(&i, nid, p_start, p_end, p_nid))
-
-void __next_free_mem_range_rev(u64 *idx, int nid, phys_addr_t *out_start,
-			       phys_addr_t *out_end, int *out_nid);
+	for_each_mem_range(i, &memblock.memory, &memblock.reserved,	\
+			   nid, p_start, p_end, p_nid)
 
 /**
  * for_each_free_mem_range_reverse - rev-iterate through free memblock areas
@@ -148,10 +197,8 @@ void __next_free_mem_range_rev(u64 *idx, int nid, phys_addr_t *out_start,
  * order.  Available as soon as memblock is initialized.
  */
 #define for_each_free_mem_range_reverse(i, nid, p_start, p_end, p_nid)	\
-	for (i = (u64)ULLONG_MAX,					\
-	     __next_free_mem_range_rev(&i, nid, p_start, p_end, p_nid);	\
-	     i != (u64)ULLONG_MAX;					\
-	     __next_free_mem_range_rev(&i, nid, p_start, p_end, p_nid))
+	for_each_mem_range_rev(i, &memblock.memory, &memblock.reserved,	\
+			       nid, p_start, p_end, p_nid)
 
 static inline void memblock_set_region_flags(struct memblock_region *r,
 					     unsigned long flags)