/*
   * include/linux/memory.h - generic memory definition
   *
   * This is mainly for topological representation. We define the
   * basic "struct memory_block" here, which can be embedded in per-arch
   * definitions or NUMA information.
   *
   * Basic handling of the devices is done in drivers/base/memory.c
   * and system devices are handled in drivers/base/sys.c.
   *
   * Memory block are exported via sysfs in the class/memory/devices/
   * directory.
   *
   */
  #ifndef _LINUX_MEMORY_H_
  #define _LINUX_MEMORY_H_

  #include <linux/node.h>
  #include <linux/compiler.h>

  #include <linux/mutex.h>

  #define MIN_MEMORY_BLOCK_SIZE     (1 << SECTION_SIZE_BITS)

  struct memory_block {

  	unsigned long start_section_nr;
  	unsigned long end_section_nr;

  	unsigned long state;

  	int section_count;

  	/*
  	 * This serializes all state change requests.  It isn't
  	 * held during creation because the control files are
  	 * created long after the critical areas during
  	 * initialization.
  	 */

  	struct mutex state_mutex;

  	int phys_device;		/* to which fru does this belong? */
  	void *hw;			/* optional pointer to fw/hw data */
  	int (*phys_callback)(struct memory_block *);

  	struct device dev;

  };

  int arch_get_memory_phys_device(unsigned long start_pfn);

  /* These states are exposed to userspace as text strings in sysfs */
  #define	MEM_ONLINE		(1<<0) /* exposed to userspace */
  #define	MEM_GOING_OFFLINE	(1<<1) /* exposed to userspace */
  #define	MEM_OFFLINE		(1<<2) /* exposed to userspace */

  #define	MEM_GOING_ONLINE	(1<<3)
  #define	MEM_CANCEL_ONLINE	(1<<4)
  #define	MEM_CANCEL_OFFLINE	(1<<5)

  struct memory_notify {
  	unsigned long start_pfn;
  	unsigned long nr_pages;
  	int status_change_nid;
  };

  /*
   * During pageblock isolation, count the number of pages within the
   * range [start_pfn, start_pfn + nr_pages) which are owned by code
   * in the notifier chain.
   */
  #define MEM_ISOLATE_COUNT	(1<<0)
  
  struct memory_isolate_notify {
  	unsigned long start_pfn;	/* Start of range to check */
  	unsigned int nr_pages;		/* # pages in range to check */
  	unsigned int pages_found;	/* # pages owned found by callbacks */
  };

  struct notifier_block;
  struct mem_section;

  /*
   * Priorities for the hotplug memory callback routines (stored in decreasing
   * order in the callback chain)
   */
  #define SLAB_CALLBACK_PRI       1

  #define IPC_CALLBACK_PRI        10

  #ifndef CONFIG_MEMORY_HOTPLUG_SPARSE

  static inline int memory_dev_init(void)
  {
  	return 0;
  }
  static inline int register_memory_notifier(struct notifier_block *nb)
  {
  	return 0;
  }
  static inline void unregister_memory_notifier(struct notifier_block *nb)
  {
  }

  static inline int memory_notify(unsigned long val, void *v)
  {
  	return 0;
  }

  static inline int register_memory_isolate_notifier(struct notifier_block *nb)
  {
  	return 0;
  }
  static inline void unregister_memory_isolate_notifier(struct notifier_block *nb)
  {
  }
  static inline int memory_isolate_notify(unsigned long val, void *v)
  {
  	return 0;
  }

  #else

  extern int register_memory_notifier(struct notifier_block *nb);
  extern void unregister_memory_notifier(struct notifier_block *nb);

  extern int register_memory_isolate_notifier(struct notifier_block *nb);
  extern void unregister_memory_isolate_notifier(struct notifier_block *nb);

  extern int register_new_memory(int, struct mem_section *);

  extern int unregister_memory_section(struct mem_section *);
  extern int memory_dev_init(void);

  extern int remove_memory_block(unsigned long, struct mem_section *, int);

  extern int memory_notify(unsigned long val, void *v);

  extern int memory_isolate_notify(unsigned long val, void *v);

  extern struct memory_block *find_memory_block_hinted(struct mem_section *,
  							struct memory_block *);

  extern struct memory_block *find_memory_block(struct mem_section *);

  #define CONFIG_MEM_BLOCK_SIZE	(PAGES_PER_SECTION<<PAGE_SHIFT)

  enum mem_add_context { BOOT, HOTPLUG };

  #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */

  #ifdef CONFIG_MEMORY_HOTPLUG

  #define hotplug_memory_notifier(fn, pri) {			\

  	static __meminitdata struct notifier_block fn##_mem_nb =\

  		{ .notifier_call = fn, .priority = pri };	\
  	register_memory_notifier(&fn##_mem_nb);			\
  }

  #else
  #define hotplug_memory_notifier(fn, pri) do { } while (0)
  #endif

  /*
   * 'struct memory_accessor' is a generic interface to provide
   * in-kernel access to persistent memory such as i2c or SPI EEPROMs
   */
  struct memory_accessor {
  	ssize_t (*read)(struct memory_accessor *, char *buf, off_t offset,
  			size_t count);
  	ssize_t (*write)(struct memory_accessor *, const char *buf,
  			 off_t offset, size_t count);
  };

  /*

   * Kernel text modification mutex, used for code patching. Users of this lock
   * can sleep.
   */
  extern struct mutex text_mutex;

  #endif /* _LINUX_MEMORY_H_ */