#ifndef __LINUX_PAGE_CGROUP_H
  #define __LINUX_PAGE_CGROUP_H

  enum {
  	/* flags for mem_cgroup */
  	PCG_LOCK,  /* Lock for pc->mem_cgroup and following bits. */
  	PCG_CACHE, /* charged as cache */
  	PCG_USED, /* this object is in use. */
  	PCG_MIGRATION, /* under page migration */
  	/* flags for mem_cgroup and file and I/O status */
  	PCG_MOVE_LOCK, /* For race between move_account v.s. following bits */
  	PCG_FILE_MAPPED, /* page is accounted as "mapped" */

  	__NR_PCG_FLAGS,
  };
  
  #ifndef __GENERATING_BOUNDS_H
  #include <generated/bounds.h>

  #ifdef CONFIG_CGROUP_MEM_RES_CTLR
  #include <linux/bit_spinlock.h>

  /*
   * Page Cgroup can be considered as an extended mem_map.
   * A page_cgroup page is associated with every page descriptor. The
   * page_cgroup helps us identify information about the cgroup
   * All page cgroups are allocated at boot or memory hotplug event,
   * then the page cgroup for pfn always exists.
   */
  struct page_cgroup {
  	unsigned long flags;
  	struct mem_cgroup *mem_cgroup;

  };

  void __meminit pgdat_page_cgroup_init(struct pglist_data *pgdat);

  
  #ifdef CONFIG_SPARSEMEM
  static inline void __init page_cgroup_init_flatmem(void)
  {
  }
  extern void __init page_cgroup_init(void);
  #else
  void __init page_cgroup_init_flatmem(void);
  static inline void __init page_cgroup_init(void)
  {
  }
  #endif

  struct page_cgroup *lookup_page_cgroup(struct page *page);

  struct page *lookup_cgroup_page(struct page_cgroup *pc);

  
  #define TESTPCGFLAG(uname, lname)			\
  static inline int PageCgroup##uname(struct page_cgroup *pc)	\
  	{ return test_bit(PCG_##lname, &pc->flags); }
  
  #define SETPCGFLAG(uname, lname)			\
  static inline void SetPageCgroup##uname(struct page_cgroup *pc)\
  	{ set_bit(PCG_##lname, &pc->flags);  }
  
  #define CLEARPCGFLAG(uname, lname)			\
  static inline void ClearPageCgroup##uname(struct page_cgroup *pc)	\
  	{ clear_bit(PCG_##lname, &pc->flags);  }

  #define TESTCLEARPCGFLAG(uname, lname)			\
  static inline int TestClearPageCgroup##uname(struct page_cgroup *pc)	\
  	{ return test_and_clear_bit(PCG_##lname, &pc->flags);  }

  /* Cache flag is set only once (at allocation) */
  TESTPCGFLAG(Cache, CACHE)

  CLEARPCGFLAG(Cache, CACHE)
  SETPCGFLAG(Cache, CACHE)

  
  TESTPCGFLAG(Used, USED)
  CLEARPCGFLAG(Used, USED)

  SETPCGFLAG(Used, USED)

  SETPCGFLAG(FileMapped, FILE_MAPPED)
  CLEARPCGFLAG(FileMapped, FILE_MAPPED)
  TESTPCGFLAG(FileMapped, FILE_MAPPED)

  SETPCGFLAG(Migration, MIGRATION)
  CLEARPCGFLAG(Migration, MIGRATION)
  TESTPCGFLAG(Migration, MIGRATION)

  static inline void lock_page_cgroup(struct page_cgroup *pc)
  {

  	/*
  	 * Don't take this lock in IRQ context.
  	 * This lock is for pc->mem_cgroup, USED, CACHE, MIGRATION
  	 */

  	bit_spin_lock(PCG_LOCK, &pc->flags);
  }

  static inline void unlock_page_cgroup(struct page_cgroup *pc)
  {
  	bit_spin_unlock(PCG_LOCK, &pc->flags);
  }

  static inline void move_lock_page_cgroup(struct page_cgroup *pc,
  	unsigned long *flags)
  {
  	/*
  	 * We know updates to pc->flags of page cache's stats are from both of
  	 * usual context or IRQ context. Disable IRQ to avoid deadlock.
  	 */
  	local_irq_save(*flags);
  	bit_spin_lock(PCG_MOVE_LOCK, &pc->flags);
  }
  
  static inline void move_unlock_page_cgroup(struct page_cgroup *pc,
  	unsigned long *flags)
  {
  	bit_spin_unlock(PCG_MOVE_LOCK, &pc->flags);
  	local_irq_restore(*flags);
  }

  #else /* CONFIG_CGROUP_MEM_RES_CTLR */
  struct page_cgroup;

  static inline void __meminit pgdat_page_cgroup_init(struct pglist_data *pgdat)

  {
  }
  
  static inline struct page_cgroup *lookup_page_cgroup(struct page *page)
  {
  	return NULL;
  }

  
  static inline void page_cgroup_init(void)
  {
  }

  static inline void __init page_cgroup_init_flatmem(void)
  {
  }

  #endif /* CONFIG_CGROUP_MEM_RES_CTLR */

  #include <linux/swap.h>

  
  #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP

  extern unsigned short swap_cgroup_cmpxchg(swp_entry_t ent,
  					unsigned short old, unsigned short new);

  extern unsigned short swap_cgroup_record(swp_entry_t ent, unsigned short id);

  extern unsigned short lookup_swap_cgroup_id(swp_entry_t ent);

  extern int swap_cgroup_swapon(int type, unsigned long max_pages);
  extern void swap_cgroup_swapoff(int type);
  #else

  
  static inline

  unsigned short swap_cgroup_record(swp_entry_t ent, unsigned short id)

  {

  	return 0;

  }
  
  static inline

  unsigned short lookup_swap_cgroup_id(swp_entry_t ent)

  {

  	return 0;

  }
  
  static inline int
  swap_cgroup_swapon(int type, unsigned long max_pages)
  {
  	return 0;
  }
  
  static inline void swap_cgroup_swapoff(int type)
  {
  	return;
  }

  #endif /* CONFIG_CGROUP_MEM_RES_CTLR_SWAP */
  
  #endif /* !__GENERATING_BOUNDS_H */
  
  #endif /* __LINUX_PAGE_CGROUP_H */