/* SPDX-License-Identifier: GPL-2.0 */

  /*
   * 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>

  #include <linux/notifier.h>

  #define MIN_MEMORY_BLOCK_SIZE     (1UL << SECTION_SIZE_BITS)

  struct memory_block {

  	unsigned long start_section_nr;

  	unsigned long state;		/* serialized by the dev->lock */

  	int online_type;		/* for passing data to online routine */

  	int phys_device;		/* to which fru does this belong? */

  	struct device dev;

  	int nid;			/* NID for this memory block */

  };

  int arch_get_memory_phys_device(unsigned long start_pfn);

  unsigned long memory_block_size_bytes(void);

  int set_memory_block_size_order(unsigned int order);

  /* 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_normal;

  	int status_change_nid_high;

  	int status_change_nid;
  };

  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 void memory_dev_init(void)

  {

  	return;

  }
  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;
  }

  #else

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

  int create_memory_block_devices(unsigned long start, unsigned long size);

  void remove_memory_block_devices(unsigned long start, unsigned long size);

  extern void memory_dev_init(void);

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

  extern struct memory_block *find_memory_block(struct mem_section *);

  typedef int (*walk_memory_blocks_func_t)(struct memory_block *, void *);
  extern int walk_memory_blocks(unsigned long start, unsigned long size,
  			      void *arg, walk_memory_blocks_func_t func);

  extern int for_each_memory_block(void *arg, walk_memory_blocks_func_t func);

  #define CONFIG_MEM_BLOCK_SIZE	(PAGES_PER_SECTION<<PAGE_SHIFT)

  #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);			\

  })
  #define register_hotmemory_notifier(nb)		register_memory_notifier(nb)
  #define unregister_hotmemory_notifier(nb) 	unregister_memory_notifier(nb)

  #else

  #define hotplug_memory_notifier(fn, pri)	({ 0; })

  /* These aren't inline functions due to a GCC bug. */
  #define register_hotmemory_notifier(nb)    ({ (void)(nb); 0; })
  #define unregister_hotmemory_notifier(nb)  ({ (void)(nb); })

  #endif

  /*

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

  #endif /* _LINUX_MEMORY_H_ */