1 files changed, 58 insertions, 10 deletions

diff --git a/mm/memblock.c b/mm/memblock.c
index 952123eba433..d4382095f8bd 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -184,7 +184,24 @@ static void __init_memblock memblock_remove_region(struct memblock_type *type, u
         }
 }
 
-static int __init_memblock memblock_double_array(struct memblock_type *type)
+/**
+ * memblock_double_array - double the size of the memblock regions array
+ * @type: memblock type of the regions array being doubled
+ * @new_area_start: starting address of memory range to avoid overlap with
+ * @new_area_size: size of memory range to avoid overlap with
+ *
+ * Double the size of the @type regions array. If memblock is being used to
+ * allocate memory for a new reserved regions array and there is a previously
+ * allocated memory range [@new_area_start,@new_area_start+@new_area_size]
+ * waiting to be reserved, ensure the memory used by the new array does
+ * not overlap.
+ *
+ * RETURNS:
+ * 0 on success, -1 on failure.
+ */
+static int __init_memblock memblock_double_array(struct memblock_type *type,
+                                                phys_addr_t new_area_start,
+                                                phys_addr_t new_area_size)
 {
         struct memblock_region *new_array, *old_array;
         phys_addr_t old_size, new_size, addr;
@@ -222,7 +239,18 @@ static int __init_memblock memblock_double_array(struct memblock_type *type)
                 new_array = kmalloc(new_size, GFP_KERNEL);
                 addr = new_array ? __pa(new_array) : 0;
         } else {
-                addr = memblock_find_in_range(0, MEMBLOCK_ALLOC_ACCESSIBLE, new_size, sizeof(phys_addr_t));
+                /* only exclude range when trying to double reserved.regions */
+                if (type != &memblock.reserved)
+                        new_area_start = new_area_size = 0;
+
+                addr = memblock_find_in_range(new_area_start + new_area_size,
+                                                memblock.current_limit,
+                                                new_size, sizeof(phys_addr_t));
+                if (!addr && new_area_size)
+                        addr = memblock_find_in_range(0,
+                                        min(new_area_start, memblock.current_limit),
+                                        new_size, sizeof(phys_addr_t));
+
                 new_array = addr ? __va(addr) : 0;
         }
         if (!addr) {
@@ -399,7 +427,7 @@ repeat:
          */
         if (!insert) {
                 while (type->cnt + nr_new > type->max)
-                        if (memblock_double_array(type) < 0)
+                        if (memblock_double_array(type, obase, size) < 0)
                                 return -ENOMEM;
                 insert = true;
                 goto repeat;
@@ -450,7 +478,7 @@ static int __init_memblock memblock_isolate_range(struct memblock_type *type,
 
         /* we'll create at most two more regions */
         while (type->cnt + 2 > type->max)
-                if (memblock_double_array(type) < 0)
+                if (memblock_double_array(type, base, size) < 0)
                         return -ENOMEM;
 
         for (i = 0; i < type->cnt; i++) {
@@ -540,9 +568,9 @@ int __init_memblock memblock_reserve(phys_addr_t base, phys_addr_t size)
  * __next_free_mem_range - next function for for_each_free_mem_range()
  * @idx: pointer to u64 loop variable
  * @nid: nid: node selector, %MAX_NUMNODES 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
+ * @out_start: ptr to phys_addr_t for start address of the range, can be %NULL
+ * @out_end: ptr to phys_addr_t for end address of the range, can be %NULL
+ * @out_nid: ptr to int for nid of the range, can be %NULL
  *
  * Find the first free area from *@idx which matches @nid, fill the out
  * parameters, and update *@idx for the next iteration.  The lower 32bit of
@@ -616,9 +644,9 @@ void __init_memblock __next_free_mem_range(u64 *idx, int nid,
  * __next_free_mem_range_rev - next function for for_each_free_mem_range_reverse()
  * @idx: pointer to u64 loop variable
  * @nid: nid: node selector, %MAX_NUMNODES 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
+ * @out_start: ptr to phys_addr_t for start address of the range, can be %NULL
+ * @out_end: ptr to phys_addr_t for end address of the range, can be %NULL
+ * @out_nid: ptr to int for nid of the range, can be %NULL
  *
  * Reverse of __next_free_mem_range().
  */
@@ -867,6 +895,16 @@ int __init_memblock memblock_is_memory(phys_addr_t addr)
         return memblock_search(&memblock.memory, addr) != -1;
 }
 
+/**
+ * memblock_is_region_memory - check if a region is a subset of memory
+ * @base: base of region to check
+ * @size: size of region to check
+ *
+ * Check if the region [@base, @base+@size) is a subset of a memory block.
+ *
+ * RETURNS:
+ * 0 if false, non-zero if true
+ */
 int __init_memblock memblock_is_region_memory(phys_addr_t base, phys_addr_t size)
 {
         int idx = memblock_search(&memblock.memory, base);
@@ -879,6 +917,16 @@ int __init_memblock memblock_is_region_memory(phys_addr_t base, phys_addr_t size
                  memblock.memory.regions[idx].size) >= end;
 }
 
+/**
+ * memblock_is_region_reserved - check if a region intersects reserved memory
+ * @base: base of region to check
+ * @size: size of region to check
+ *
+ * Check if the region [@base, @base+@size) intersects a reserved memory block.
+ *
+ * RETURNS:
+ * 0 if false, non-zero if true
+ */
 int __init_memblock memblock_is_region_reserved(phys_addr_t base, phys_addr_t size)
 {
         memblock_cap_size(base, &size);