1 files changed, 138 insertions, 0 deletions

diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
new file mode 100644
index 000000000000..431a64f021c0
--- /dev/null
+++ b/mm/memory_hotplug.c
@@ -0,0 +1,138 @@
+/*
+ *  linux/mm/memory_hotplug.c
+ *
+ *  Copyright (C)
+ */
+
+#include <linux/config.h>
+#include <linux/stddef.h>
+#include <linux/mm.h>
+#include <linux/swap.h>
+#include <linux/interrupt.h>
+#include <linux/pagemap.h>
+#include <linux/bootmem.h>
+#include <linux/compiler.h>
+#include <linux/module.h>
+#include <linux/pagevec.h>
+#include <linux/slab.h>
+#include <linux/sysctl.h>
+#include <linux/cpu.h>
+#include <linux/memory.h>
+#include <linux/memory_hotplug.h>
+#include <linux/highmem.h>
+#include <linux/vmalloc.h>
+
+#include <asm/tlbflush.h>
+
+extern void zonetable_add(struct zone *zone, int nid, int zid, unsigned long pfn,
+                          unsigned long size);
+static void __add_zone(struct zone *zone, unsigned long phys_start_pfn)
+{
+        struct pglist_data *pgdat = zone->zone_pgdat;
+        int nr_pages = PAGES_PER_SECTION;
+        int nid = pgdat->node_id;
+        int zone_type;
+
+        zone_type = zone - pgdat->node_zones;
+        memmap_init_zone(nr_pages, nid, zone_type, phys_start_pfn);
+        zonetable_add(zone, nid, zone_type, phys_start_pfn, nr_pages);
+}
+
+extern int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
+                                  int nr_pages);
+static int __add_section(struct zone *zone, unsigned long phys_start_pfn)
+{
+        struct pglist_data *pgdat = zone->zone_pgdat;
+        int nr_pages = PAGES_PER_SECTION;
+        int ret;
+
+        ret = sparse_add_one_section(zone, phys_start_pfn, nr_pages);
+
+        if (ret < 0)
+                return ret;
+
+        __add_zone(zone, phys_start_pfn);
+        return register_new_memory(__pfn_to_section(phys_start_pfn));
+}
+
+/*
+ * Reasonably generic function for adding memory.  It is
+ * expected that archs that support memory hotplug will
+ * call this function after deciding the zone to which to
+ * add the new pages.
+ */
+int __add_pages(struct zone *zone, unsigned long phys_start_pfn,
+                 unsigned long nr_pages)
+{
+        unsigned long i;
+        int err = 0;
+
+        for (i = 0; i < nr_pages; i += PAGES_PER_SECTION) {
+                err = __add_section(zone, phys_start_pfn + i);
+
+                if (err)
+                        break;
+        }
+
+        return err;
+}
+
+static void grow_zone_span(struct zone *zone,
+                unsigned long start_pfn, unsigned long end_pfn)
+{
+        unsigned long old_zone_end_pfn;
+
+        zone_span_writelock(zone);
+
+        old_zone_end_pfn = zone->zone_start_pfn + zone->spanned_pages;
+        if (start_pfn < zone->zone_start_pfn)
+                zone->zone_start_pfn = start_pfn;
+
+        if (end_pfn > old_zone_end_pfn)
+                zone->spanned_pages = end_pfn - zone->zone_start_pfn;
+
+        zone_span_writeunlock(zone);
+}
+
+static void grow_pgdat_span(struct pglist_data *pgdat,
+                unsigned long start_pfn, unsigned long end_pfn)
+{
+        unsigned long old_pgdat_end_pfn =
+                pgdat->node_start_pfn + pgdat->node_spanned_pages;
+
+        if (start_pfn < pgdat->node_start_pfn)
+                pgdat->node_start_pfn = start_pfn;
+
+        if (end_pfn > old_pgdat_end_pfn)
+                pgdat->node_spanned_pages = end_pfn - pgdat->node_spanned_pages;
+}
+
+int online_pages(unsigned long pfn, unsigned long nr_pages)
+{
+        unsigned long i;
+        unsigned long flags;
+        unsigned long onlined_pages = 0;
+        struct zone *zone;
+
+        /*
+         * This doesn't need a lock to do pfn_to_page().
+         * The section can't be removed here because of the
+         * memory_block->state_sem.
+         */
+        zone = page_zone(pfn_to_page(pfn));
+        pgdat_resize_lock(zone->zone_pgdat, &flags);
+        grow_zone_span(zone, pfn, pfn + nr_pages);
+        grow_pgdat_span(zone->zone_pgdat, pfn, pfn + nr_pages);
+        pgdat_resize_unlock(zone->zone_pgdat, &flags);
+
+        for (i = 0; i < nr_pages; i++) {
+                struct page *page = pfn_to_page(pfn + i);
+                online_page(page);
+                onlined_pages++;
+        }
+        zone->present_pages += onlined_pages;
+
+        setup_per_zone_pages_min();
+
+        return 0;
+}