#include <linux/mm.h>
  #include <linux/mmzone.h>
  #include <linux/bootmem.h>
  #include <linux/bit_spinlock.h>
  #include <linux/page_cgroup.h>
  #include <linux/hash.h>

  #include <linux/slab.h>

  #include <linux/memory.h>

  #include <linux/vmalloc.h>

  #include <linux/cgroup.h>

  
  static void __meminit
  __init_page_cgroup(struct page_cgroup *pc, unsigned long pfn)
  {
  	pc->flags = 0;
  	pc->mem_cgroup = NULL;
  	pc->page = pfn_to_page(pfn);
  }
  static unsigned long total_usage;
  
  #if !defined(CONFIG_SPARSEMEM)

  void __meminit pgdat_page_cgroup_init(struct pglist_data *pgdat)

  {
  	pgdat->node_page_cgroup = NULL;
  }
  
  struct page_cgroup *lookup_page_cgroup(struct page *page)
  {
  	unsigned long pfn = page_to_pfn(page);
  	unsigned long offset;
  	struct page_cgroup *base;
  
  	base = NODE_DATA(page_to_nid(page))->node_page_cgroup;
  	if (unlikely(!base))
  		return NULL;
  
  	offset = pfn - NODE_DATA(page_to_nid(page))->node_start_pfn;
  	return base + offset;
  }
  
  static int __init alloc_node_page_cgroup(int nid)
  {
  	struct page_cgroup *base, *pc;
  	unsigned long table_size;
  	unsigned long start_pfn, nr_pages, index;
  
  	start_pfn = NODE_DATA(nid)->node_start_pfn;
  	nr_pages = NODE_DATA(nid)->node_spanned_pages;

  	if (!nr_pages)
  		return 0;

  	table_size = sizeof(struct page_cgroup) * nr_pages;
  
  	base = __alloc_bootmem_node_nopanic(NODE_DATA(nid),
  			table_size, PAGE_SIZE, __pa(MAX_DMA_ADDRESS));
  	if (!base)
  		return -ENOMEM;
  	for (index = 0; index < nr_pages; index++) {
  		pc = base + index;
  		__init_page_cgroup(pc, start_pfn + index);
  	}
  	NODE_DATA(nid)->node_page_cgroup = base;
  	total_usage += table_size;
  	return 0;
  }
  
  void __init page_cgroup_init(void)
  {
  
  	int nid, fail;

  	if (mem_cgroup_subsys.disabled)
  		return;

  	for_each_online_node(nid)  {
  		fail = alloc_node_page_cgroup(nid);
  		if (fail)
  			goto fail;
  	}
  	printk(KERN_INFO "allocated %ld bytes of page_cgroup
  ", total_usage);
  	printk(KERN_INFO "please try cgroup_disable=memory option if you"
  	" don't want
  ");
  	return;
  fail:
  	printk(KERN_CRIT "allocation of page_cgroup was failed.
  ");
  	printk(KERN_CRIT "please try cgroup_disable=memory boot option
  ");
  	panic("Out of memory");
  }
  
  #else /* CONFIG_FLAT_NODE_MEM_MAP */
  
  struct page_cgroup *lookup_page_cgroup(struct page *page)
  {
  	unsigned long pfn = page_to_pfn(page);
  	struct mem_section *section = __pfn_to_section(pfn);
  
  	return section->page_cgroup + pfn;
  }

  /* __alloc_bootmem...() is protected by !slab_available() */
  int __init_refok init_section_page_cgroup(unsigned long pfn)

  {
  	struct mem_section *section;
  	struct page_cgroup *base, *pc;
  	unsigned long table_size;
  	int nid, index;
  
  	section = __pfn_to_section(pfn);

  	if (!section->page_cgroup) {
  		nid = page_to_nid(pfn_to_page(pfn));
  		table_size = sizeof(struct page_cgroup) * PAGES_PER_SECTION;
  		if (slab_is_available()) {
  			base = kmalloc_node(table_size, GFP_KERNEL, nid);
  			if (!base)
  				base = vmalloc_node(table_size, nid);
  		} else {
  			base = __alloc_bootmem_node_nopanic(NODE_DATA(nid),
  				table_size,

  				PAGE_SIZE, __pa(MAX_DMA_ADDRESS));

  		}
  	} else {
  		/*
   		 * We don't have to allocate page_cgroup again, but
  		 * address of memmap may be changed. So, we have to initialize
  		 * again.
  		 */
  		base = section->page_cgroup + pfn;
  		table_size = 0;
  		/* check address of memmap is changed or not. */
  		if (base->page == pfn_to_page(pfn))
  			return 0;

  	}

  
  	if (!base) {
  		printk(KERN_ERR "page cgroup allocation failure
  ");
  		return -ENOMEM;
  	}
  
  	for (index = 0; index < PAGES_PER_SECTION; index++) {
  		pc = base + index;
  		__init_page_cgroup(pc, pfn + index);
  	}
  
  	section = __pfn_to_section(pfn);
  	section->page_cgroup = base - pfn;
  	total_usage += table_size;
  	return 0;
  }
  #ifdef CONFIG_MEMORY_HOTPLUG
  void __free_page_cgroup(unsigned long pfn)
  {
  	struct mem_section *ms;
  	struct page_cgroup *base;
  
  	ms = __pfn_to_section(pfn);
  	if (!ms || !ms->page_cgroup)
  		return;
  	base = ms->page_cgroup + pfn;

  	if (is_vmalloc_addr(base)) {

  		vfree(base);

  		ms->page_cgroup = NULL;
  	} else {
  		struct page *page = virt_to_page(base);
  		if (!PageReserved(page)) { /* Is bootmem ? */
  			kfree(base);
  			ms->page_cgroup = NULL;
  		}
  	}

  }

  int __meminit online_page_cgroup(unsigned long start_pfn,

  			unsigned long nr_pages,
  			int nid)
  {
  	unsigned long start, end, pfn;
  	int fail = 0;

  	start = start_pfn & ~(PAGES_PER_SECTION - 1);

  	end = ALIGN(start_pfn + nr_pages, PAGES_PER_SECTION);
  
  	for (pfn = start; !fail && pfn < end; pfn += PAGES_PER_SECTION) {
  		if (!pfn_present(pfn))
  			continue;
  		fail = init_section_page_cgroup(pfn);
  	}
  	if (!fail)
  		return 0;
  
  	/* rollback */
  	for (pfn = start; pfn < end; pfn += PAGES_PER_SECTION)
  		__free_page_cgroup(pfn);
  
  	return -ENOMEM;
  }

  int __meminit offline_page_cgroup(unsigned long start_pfn,

  		unsigned long nr_pages, int nid)
  {
  	unsigned long start, end, pfn;

  	start = start_pfn & ~(PAGES_PER_SECTION - 1);

  	end = ALIGN(start_pfn + nr_pages, PAGES_PER_SECTION);
  
  	for (pfn = start; pfn < end; pfn += PAGES_PER_SECTION)
  		__free_page_cgroup(pfn);
  	return 0;
  
  }

  static int __meminit page_cgroup_callback(struct notifier_block *self,

  			       unsigned long action, void *arg)
  {
  	struct memory_notify *mn = arg;
  	int ret = 0;
  	switch (action) {
  	case MEM_GOING_ONLINE:
  		ret = online_page_cgroup(mn->start_pfn,
  				   mn->nr_pages, mn->status_change_nid);
  		break;

  	case MEM_OFFLINE:
  		offline_page_cgroup(mn->start_pfn,
  				mn->nr_pages, mn->status_change_nid);
  		break;

  	case MEM_CANCEL_ONLINE:

  	case MEM_GOING_OFFLINE:
  		break;
  	case MEM_ONLINE:
  	case MEM_CANCEL_OFFLINE:
  		break;
  	}

  
  	if (ret)
  		ret = notifier_from_errno(ret);
  	else
  		ret = NOTIFY_OK;

  	return ret;
  }
  
  #endif
  
  void __init page_cgroup_init(void)
  {
  	unsigned long pfn;
  	int fail = 0;

  	if (mem_cgroup_subsys.disabled)
  		return;

  	for (pfn = 0; !fail && pfn < max_pfn; pfn += PAGES_PER_SECTION) {
  		if (!pfn_present(pfn))
  			continue;
  		fail = init_section_page_cgroup(pfn);
  	}
  	if (fail) {
  		printk(KERN_CRIT "try cgroup_disable=memory boot option
  ");
  		panic("Out of memory");
  	} else {
  		hotplug_memory_notifier(page_cgroup_callback, 0);
  	}
  	printk(KERN_INFO "allocated %ld bytes of page_cgroup
  ", total_usage);
  	printk(KERN_INFO "please try cgroup_disable=memory option if you don't"
  	" want
  ");
  }

  void __meminit pgdat_page_cgroup_init(struct pglist_data *pgdat)

  {
  	return;
  }
  
  #endif