1 files changed, 52 insertions, 10 deletions

diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c
index e3734edffa69..fa5d28b4e726 100644
--- a/arch/powerpc/mm/init_64.c
+++ b/arch/powerpc/mm/init_64.c
@@ -226,14 +226,24 @@ static void __meminit vmemmap_create_mapping(unsigned long start,
 #endif /* CONFIG_PPC_BOOK3E */
 
 struct vmemmap_backing *vmemmap_list;
+static struct vmemmap_backing *next;
+static int num_left;
+static int num_freed;
 
 static __meminit struct vmemmap_backing * vmemmap_list_alloc(int node)
 {
-        static struct vmemmap_backing *next;
-        static int num_left;
+        struct vmemmap_backing *vmem_back;
+        /* get from freed entries first */
+        if (num_freed) {
+                num_freed--;
+                vmem_back = next;
+                next = next->list;
+
+                return vmem_back;
+        }
 
         /* allocate a page when required and hand out chunks */
-        if (!next || !num_left) {
+        if (!num_left) {
                 next = vmemmap_alloc_block(PAGE_SIZE, node);
                 if (unlikely(!next)) {
                         WARN_ON(1);
@@ -266,6 +276,38 @@ static __meminit void vmemmap_list_populate(unsigned long phys,
         vmemmap_list = vmem_back;
 }
 
+static unsigned long vmemmap_list_free(unsigned long start)
+{
+        struct vmemmap_backing *vmem_back, *vmem_back_prev;
+
+        vmem_back_prev = vmem_back = vmemmap_list;
+
+        /* look for it with prev pointer recorded */
+        for (; vmem_back; vmem_back = vmem_back->list) {
+                if (vmem_back->virt_addr == start)
+                        break;
+                vmem_back_prev = vmem_back;
+        }
+
+        if (unlikely(!vmem_back)) {
+                WARN_ON(1);
+                return 0;
+        }
+
+        /* remove it from vmemmap_list */
+        if (vmem_back == vmemmap_list) /* remove head */
+                vmemmap_list = vmem_back->list;
+        else
+                vmem_back_prev->list = vmem_back->list;
+
+        /* next point to this freed entry */
+        vmem_back->list = next;
+        next = vmem_back;
+        num_freed++;
+
+        return vmem_back->phys;
+}
+
 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
 {
         unsigned long page_size = 1 << mmu_psize_defs[mmu_vmemmap_psize].shift;
@@ -331,16 +373,16 @@ struct page *realmode_pfn_to_page(unsigned long pfn)
                 if (pg_va < vmem_back->virt_addr)
                         continue;
 
-                /* Check that page struct is not split between real pages */
-                if ((pg_va + sizeof(struct page)) >
-                                (vmem_back->virt_addr + page_size))
-                        return NULL;
-
-                page = (struct page *) (vmem_back->phys + pg_va -
+                /* After vmemmap_list entry free is possible, need check all */
+                if ((pg_va + sizeof(struct page)) <=
+                                (vmem_back->virt_addr + page_size)) {
+                        page = (struct page *) (vmem_back->phys + pg_va -
                                 vmem_back->virt_addr);
-                return page;
+                        return page;
+                }
         }
 
+        /* Probably that page struct is split between real pages */
         return NULL;
 }
 EXPORT_SYMBOL_GPL(realmode_pfn_to_page);