memblock: Add "start" argument to memblock_find_base()

To constraint the search of a region between two boundaries,
which will be used by the new NUMA aware allocator among others.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 16 insertions, 11 deletions

diff --git a/mm/memblock.c b/mm/memblock.c
index 8715f09434df..468ff43a72b4 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -117,19 +117,18 @@ static phys_addr_t __init memblock_find_region(phys_addr_t start, phys_addr_t en
         return MEMBLOCK_ERROR;
 }
 
-static phys_addr_t __init memblock_find_base(phys_addr_t size, phys_addr_t align, phys_addr_t max_addr)
+static phys_addr_t __init memblock_find_base(phys_addr_t size, phys_addr_t align,
+                                        phys_addr_t start, phys_addr_t end)
 {
         long i;
-        phys_addr_t base = 0;
-        phys_addr_t res_base;
 
         BUG_ON(0 == size);
 
         size = memblock_align_up(size, align);
 
         /* Pump up max_addr */
-        if (max_addr == MEMBLOCK_ALLOC_ACCESSIBLE)
-                max_addr = memblock.current_limit;
+        if (end == MEMBLOCK_ALLOC_ACCESSIBLE)
+                end = memblock.current_limit;
 
         /* We do a top-down search, this tends to limit memory
          * fragmentation by keeping early boot allocs near the
@@ -138,13 +137,19 @@ static phys_addr_t __init memblock_find_base(phys_addr_t size, phys_addr_t align
         for (i = memblock.memory.cnt - 1; i >= 0; i--) {
                 phys_addr_t memblockbase = memblock.memory.regions[i].base;
                 phys_addr_t memblocksize = memblock.memory.regions[i].size;
+                phys_addr_t bottom, top, found;
 
                 if (memblocksize < size)
                         continue;
-                base = min(memblockbase + memblocksize, max_addr);
-                res_base = memblock_find_region(memblockbase, base, size, align);
-                if (res_base != MEMBLOCK_ERROR)
-                        return res_base;
+                if ((memblockbase + memblocksize) <= start)
+                        break;
+                bottom = max(memblockbase, start);
+                top = min(memblockbase + memblocksize, end);
+                if (bottom >= top)
+                        continue;
+                found = memblock_find_region(bottom, top, size, align);
+                if (found != MEMBLOCK_ERROR)
+                        return found;
         }
         return MEMBLOCK_ERROR;
 }
@@ -204,7 +209,7 @@ static int memblock_double_array(struct memblock_type *type)
                 new_array = kmalloc(new_size, GFP_KERNEL);
                 addr = new_array == NULL ? MEMBLOCK_ERROR : __pa(new_array);
         } else
-                addr = memblock_find_base(new_size, sizeof(phys_addr_t), MEMBLOCK_ALLOC_ACCESSIBLE);
+                addr = memblock_find_base(new_size, sizeof(phys_addr_t), 0, MEMBLOCK_ALLOC_ACCESSIBLE);
         if (addr == MEMBLOCK_ERROR) {
                 pr_err("memblock: Failed to double %s array from %ld to %ld entries !\n",
                        memblock_type_name(type), type->max, type->max * 2);
@@ -416,7 +421,7 @@ phys_addr_t __init __memblock_alloc_base(phys_addr_t size, phys_addr_t align, ph
          */
         size = memblock_align_up(size, align);
 
-        found = memblock_find_base(size, align, max_addr);
+        found = memblock_find_base(size, align, 0, max_addr);
         if (found != MEMBLOCK_ERROR &&
             memblock_add_region(&memblock.reserved, found, size) >= 0)
                 return found;