1 files changed, 47 insertions, 4 deletions

diff --git a/mm/sparse.c b/mm/sparse.c
index 08f053218ee8..dff71f173ae9 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -8,6 +8,7 @@
 #include <linux/module.h>
 #include <linux/spinlock.h>
 #include <linux/vmalloc.h>
+#include "internal.h"
 #include <asm/dma.h>
 #include <asm/pgalloc.h>
 #include <asm/pgtable.h>
@@ -376,6 +377,9 @@ static void __kfree_section_memmap(struct page *memmap, unsigned long nr_pages)
 {
         return; /* XXX: Not implemented yet */
 }
+static void free_map_bootmem(struct page *page, unsigned long nr_pages)
+{
+}
 #else
 static struct page *__kmalloc_section_memmap(unsigned long nr_pages)
 {
@@ -413,17 +417,47 @@ static void __kfree_section_memmap(struct page *memmap, unsigned long nr_pages)
                 free_pages((unsigned long)memmap,
                            get_order(sizeof(struct page) * nr_pages));
 }
+
+static void free_map_bootmem(struct page *page, unsigned long nr_pages)
+{
+        unsigned long maps_section_nr, removing_section_nr, i;
+        int magic;
+
+        for (i = 0; i < nr_pages; i++, page++) {
+                magic = atomic_read(&page->_mapcount);
+
+                BUG_ON(magic == NODE_INFO);
+
+                maps_section_nr = pfn_to_section_nr(page_to_pfn(page));
+                removing_section_nr = page->private;
+
+                /*
+                 * When this function is called, the removing section is
+                 * logical offlined state. This means all pages are isolated
+                 * from page allocator. If removing section's memmap is placed
+                 * on the same section, it must not be freed.
+                 * If it is freed, page allocator may allocate it which will
+                 * be removed physically soon.
+                 */
+                if (maps_section_nr != removing_section_nr)
+                        put_page_bootmem(page);
+        }
+}
 #endif /* CONFIG_SPARSEMEM_VMEMMAP */
 
 static void free_section_usemap(struct page *memmap, unsigned long *usemap)
 {
+        struct page *usemap_page;
+        unsigned long nr_pages;
+
         if (!usemap)
                 return;
 
+        usemap_page = virt_to_page(usemap);
         /*
          * Check to see if allocation came from hot-plug-add
          */
-        if (PageSlab(virt_to_page(usemap))) {
+        if (PageSlab(usemap_page)) {
                 kfree(usemap);
                 if (memmap)
                         __kfree_section_memmap(memmap, PAGES_PER_SECTION);
@@ -431,10 +465,19 @@ static void free_section_usemap(struct page *memmap, unsigned long *usemap)
         }
 
         /*
-         * TODO: Allocations came from bootmem - how do I free up ?
+         * The usemap came from bootmem. This is packed with other usemaps
+         * on the section which has pgdat at boot time. Just keep it as is now.
          */
-        printk(KERN_WARNING "Not freeing up allocations from bootmem "
-                        "- leaking memory\n");
+
+        if (memmap) {
+                struct page *memmap_page;
+                memmap_page = virt_to_page(memmap);
+
+                nr_pages = PAGE_ALIGN(PAGES_PER_SECTION * sizeof(struct page))
+                        >> PAGE_SHIFT;
+
+                free_map_bootmem(memmap_page, nr_pages);
+        }
 }
 
 /*