1 files changed, 43 insertions, 22 deletions

diff --git a/mm/bootmem.c b/mm/bootmem.c
index 94ea612deccf..9d03ff651359 100644
--- a/mm/bootmem.c
+++ b/mm/bootmem.c
@@ -225,6 +225,44 @@ unsigned long __init free_all_bootmem(void)
         return free_all_bootmem_core(NODE_DATA(0)->bdata);
 }
 
+static void __init __free(bootmem_data_t *bdata,
+                        unsigned long sidx, unsigned long eidx)
+{
+        unsigned long idx;
+
+        bdebug("nid=%td start=%lx end=%lx\n", bdata - bootmem_node_data,
+                sidx + PFN_DOWN(bdata->node_boot_start),
+                eidx + PFN_DOWN(bdata->node_boot_start));
+
+        for (idx = sidx; idx < eidx; idx++)
+                if (!test_and_clear_bit(idx, bdata->node_bootmem_map))
+                        BUG();
+}
+
+static int __init __reserve(bootmem_data_t *bdata, unsigned long sidx,
+                        unsigned long eidx, int flags)
+{
+        unsigned long idx;
+        int exclusive = flags & BOOTMEM_EXCLUSIVE;
+
+        bdebug("nid=%td start=%lx end=%lx flags=%x\n",
+                bdata - bootmem_node_data,
+                sidx + PFN_DOWN(bdata->node_boot_start),
+                eidx + PFN_DOWN(bdata->node_boot_start),
+                flags);
+
+        for (idx = sidx; idx < eidx; idx++)
+                if (test_and_set_bit(idx, bdata->node_bootmem_map)) {
+                        if (exclusive) {
+                                __free(bdata, sidx, idx);
+                                return -EBUSY;
+                        }
+                        bdebug("silent double reserve of PFN %lx\n",
+                                idx + PFN_DOWN(bdata->node_boot_start));
+                }
+        return 0;
+}
+
 static void __init free_bootmem_core(bootmem_data_t *bdata, unsigned long addr,
                                      unsigned long size)
 {
@@ -258,14 +296,7 @@ static void __init free_bootmem_core(bootmem_data_t *bdata, unsigned long addr,
         if (eidx > bdata->node_low_pfn - PFN_DOWN(bdata->node_boot_start))
                 eidx = bdata->node_low_pfn - PFN_DOWN(bdata->node_boot_start);
 
-        bdebug("nid=%td start=%lx end=%lx\n", bdata - bootmem_node_data,
-                sidx + PFN_DOWN(bdata->node_boot_start),
-                eidx + PFN_DOWN(bdata->node_boot_start));
-
-        for (i = sidx; i < eidx; i++) {
-                if (unlikely(!test_and_clear_bit(i, bdata->node_bootmem_map)))
-                        BUG();
-        }
+        __free(bdata, sidx, eidx);
 }
 
 /**
@@ -367,16 +398,7 @@ static void __init reserve_bootmem_core(bootmem_data_t *bdata,
         if (eidx > bdata->node_low_pfn - PFN_DOWN(bdata->node_boot_start))
                 eidx = bdata->node_low_pfn - PFN_DOWN(bdata->node_boot_start);
 
-        bdebug("nid=%td start=%lx end=%lx flags=%x\n",
-                bdata - bootmem_node_data,
-                sidx + PFN_DOWN(bdata->node_boot_start),
-                eidx + PFN_DOWN(bdata->node_boot_start),
-                flags);
-
-        for (i = sidx; i < eidx; i++)
-                if (test_and_set_bit(i, bdata->node_bootmem_map))
-                        bdebug("hm, page %lx reserved twice.\n",
-                                PFN_DOWN(bdata->node_boot_start) + i);
+        return __reserve(bdata, sidx, eidx, flags);
 }
 
 /**
@@ -511,10 +533,9 @@ find_block:
                 /*
                  * Reserve the area now:
                  */
-                for (i = PFN_DOWN(start_off) + merge;
-                                i < PFN_UP(end_off); i++)
-                        if (test_and_set_bit(i, bdata->node_bootmem_map))
-                                BUG();
+                if (__reserve(bdata, PFN_DOWN(start_off) + merge,
+                                PFN_UP(end_off), BOOTMEM_EXCLUSIVE))
+                        BUG();
 
                 region = phys_to_virt(bdata->node_boot_start + start_off);
                 memset(region, 0, size);