#ifndef MM_SLAB_H
  #define MM_SLAB_H
  /*
   * Internal slab definitions
   */

  #ifdef CONFIG_SLOB
  /*
   * Common fields provided in kmem_cache by all slab allocators
   * This struct is either used directly by the allocator (SLOB)
   * or the allocator must include definitions for all fields
   * provided in kmem_cache_common in their definition of kmem_cache.
   *
   * Once we can do anonymous structs (C11 standard) we could put a
   * anonymous struct definition in these allocators so that the
   * separate allocations in the kmem_cache structure of SLAB and
   * SLUB is no longer needed.
   */
  struct kmem_cache {
  	unsigned int object_size;/* The original size of the object */
  	unsigned int size;	/* The aligned/padded/added on size  */
  	unsigned int align;	/* Alignment as calculated */
  	unsigned long flags;	/* Active flags on the slab */
  	const char *name;	/* Slab name for sysfs */
  	int refcount;		/* Use counter */
  	void (*ctor)(void *);	/* Called on object slot creation */
  	struct list_head list;	/* List of all slab caches on the system */
  };
  
  #endif /* CONFIG_SLOB */
  
  #ifdef CONFIG_SLAB
  #include <linux/slab_def.h>
  #endif
  
  #ifdef CONFIG_SLUB
  #include <linux/slub_def.h>
  #endif
  
  #include <linux/memcontrol.h>

  /*
   * State of the slab allocator.
   *
   * This is used to describe the states of the allocator during bootup.
   * Allocators use this to gradually bootstrap themselves. Most allocators
   * have the problem that the structures used for managing slab caches are
   * allocated from slab caches themselves.
   */
  enum slab_state {
  	DOWN,			/* No slab functionality yet */
  	PARTIAL,		/* SLUB: kmem_cache_node available */

  	PARTIAL_NODE,		/* SLAB: kmalloc size for node struct available */

  	UP,			/* Slab caches usable but not all extras yet */
  	FULL			/* Everything is working */
  };
  
  extern enum slab_state slab_state;

  /* The slab cache mutex protects the management structures during changes */
  extern struct mutex slab_mutex;

  
  /* The list of all slab caches on the system */

  extern struct list_head slab_caches;

  /* The slab cache that manages slab cache information */
  extern struct kmem_cache *kmem_cache;

  unsigned long calculate_alignment(unsigned long flags,
  		unsigned long align, unsigned long size);

  #ifndef CONFIG_SLOB
  /* Kmalloc array related functions */
  void create_kmalloc_caches(unsigned long);

  
  /* Find the kmalloc slab corresponding for a certain size */
  struct kmem_cache *kmalloc_slab(size_t, gfp_t);

  #endif

  /* Functions provided by the slab allocators */

  extern int __kmem_cache_create(struct kmem_cache *, unsigned long flags);

  extern struct kmem_cache *create_kmalloc_cache(const char *name, size_t size,
  			unsigned long flags);
  extern void create_boot_cache(struct kmem_cache *, const char *name,
  			size_t size, unsigned long flags);

  int slab_unmergeable(struct kmem_cache *s);
  struct kmem_cache *find_mergeable(size_t size, size_t align,
  		unsigned long flags, const char *name, void (*ctor)(void *));

  #ifndef CONFIG_SLOB

  struct kmem_cache *

  __kmem_cache_alias(const char *name, size_t size, size_t align,
  		   unsigned long flags, void (*ctor)(void *));

  
  unsigned long kmem_cache_flags(unsigned long object_size,
  	unsigned long flags, const char *name,
  	void (*ctor)(void *));

  #else

  static inline struct kmem_cache *

  __kmem_cache_alias(const char *name, size_t size, size_t align,
  		   unsigned long flags, void (*ctor)(void *))

  { return NULL; }

  
  static inline unsigned long kmem_cache_flags(unsigned long object_size,
  	unsigned long flags, const char *name,
  	void (*ctor)(void *))
  {
  	return flags;
  }

  #endif

  /* Legal flag mask for kmem_cache_create(), for various configurations */
  #define SLAB_CORE_FLAGS (SLAB_HWCACHE_ALIGN | SLAB_CACHE_DMA | SLAB_PANIC | \
  			 SLAB_DESTROY_BY_RCU | SLAB_DEBUG_OBJECTS )
  
  #if defined(CONFIG_DEBUG_SLAB)
  #define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER)
  #elif defined(CONFIG_SLUB_DEBUG)
  #define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \
  			  SLAB_TRACE | SLAB_DEBUG_FREE)
  #else
  #define SLAB_DEBUG_FLAGS (0)
  #endif
  
  #if defined(CONFIG_SLAB)
  #define SLAB_CACHE_FLAGS (SLAB_MEM_SPREAD | SLAB_NOLEAKTRACE | \
  			  SLAB_RECLAIM_ACCOUNT | SLAB_TEMPORARY | SLAB_NOTRACK)
  #elif defined(CONFIG_SLUB)
  #define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \
  			  SLAB_TEMPORARY | SLAB_NOTRACK)
  #else
  #define SLAB_CACHE_FLAGS (0)
  #endif
  
  #define CACHE_CREATE_MASK (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS | SLAB_CACHE_FLAGS)

  int __kmem_cache_shutdown(struct kmem_cache *);

  int __kmem_cache_shrink(struct kmem_cache *, bool);

  void slab_kmem_cache_release(struct kmem_cache *);

  struct seq_file;
  struct file;

  struct slabinfo {
  	unsigned long active_objs;
  	unsigned long num_objs;
  	unsigned long active_slabs;
  	unsigned long num_slabs;
  	unsigned long shared_avail;
  	unsigned int limit;
  	unsigned int batchcount;
  	unsigned int shared;
  	unsigned int objects_per_slab;
  	unsigned int cache_order;
  };
  
  void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo);
  void slabinfo_show_stats(struct seq_file *m, struct kmem_cache *s);

  ssize_t slabinfo_write(struct file *file, const char __user *buffer,
  		       size_t count, loff_t *ppos);

  
  #ifdef CONFIG_MEMCG_KMEM

  /*
   * Iterate over all memcg caches of the given root cache. The caller must hold
   * slab_mutex.
   */
  #define for_each_memcg_cache(iter, root) \
  	list_for_each_entry(iter, &(root)->memcg_params.list, \
  			    memcg_params.list)
  
  #define for_each_memcg_cache_safe(iter, tmp, root) \
  	list_for_each_entry_safe(iter, tmp, &(root)->memcg_params.list, \
  				 memcg_params.list)

  static inline bool is_root_cache(struct kmem_cache *s)
  {

  	return s->memcg_params.is_root_cache;

  }

  static inline bool slab_equal_or_root(struct kmem_cache *s,

  				      struct kmem_cache *p)

  {

  	return p == s || p == s->memcg_params.root_cache;

  }

  
  /*
   * We use suffixes to the name in memcg because we can't have caches
   * created in the system with the same name. But when we print them
   * locally, better refer to them with the base name
   */
  static inline const char *cache_name(struct kmem_cache *s)
  {
  	if (!is_root_cache(s))

  		s = s->memcg_params.root_cache;

  	return s->name;
  }

  /*
   * Note, we protect with RCU only the memcg_caches array, not per-memcg caches.

   * That said the caller must assure the memcg's cache won't go away by either
   * taking a css reference to the owner cgroup, or holding the slab_mutex.

   */

  static inline struct kmem_cache *
  cache_from_memcg_idx(struct kmem_cache *s, int idx)

  {

  	struct kmem_cache *cachep;

  	struct memcg_cache_array *arr;

  
  	rcu_read_lock();

  	arr = rcu_dereference(s->memcg_params.memcg_caches);

  
  	/*
  	 * Make sure we will access the up-to-date value. The code updating
  	 * memcg_caches issues a write barrier to match this (see

  	 * memcg_create_kmem_cache()).

  	 */

  	cachep = lockless_dereference(arr->entries[idx]);

  	rcu_read_unlock();

  	return cachep;

  }

  
  static inline struct kmem_cache *memcg_root_cache(struct kmem_cache *s)
  {
  	if (is_root_cache(s))
  		return s;

  	return s->memcg_params.root_cache;

  }

  
  static __always_inline int memcg_charge_slab(struct kmem_cache *s,
  					     gfp_t gfp, int order)
  {
  	if (!memcg_kmem_enabled())
  		return 0;
  	if (is_root_cache(s))
  		return 0;

  	return memcg_charge_kmem(s->memcg_params.memcg, gfp, 1 << order);

  }
  
  static __always_inline void memcg_uncharge_slab(struct kmem_cache *s, int order)
  {
  	if (!memcg_kmem_enabled())
  		return;
  	if (is_root_cache(s))
  		return;

  	memcg_uncharge_kmem(s->memcg_params.memcg, 1 << order);

  }

  
  extern void slab_init_memcg_params(struct kmem_cache *);
  
  #else /* !CONFIG_MEMCG_KMEM */

  #define for_each_memcg_cache(iter, root) \
  	for ((void)(iter), (void)(root); 0; )
  #define for_each_memcg_cache_safe(iter, tmp, root) \
  	for ((void)(iter), (void)(tmp), (void)(root); 0; )

  static inline bool is_root_cache(struct kmem_cache *s)
  {
  	return true;
  }

  static inline bool slab_equal_or_root(struct kmem_cache *s,
  				      struct kmem_cache *p)
  {
  	return true;
  }

  
  static inline const char *cache_name(struct kmem_cache *s)
  {
  	return s->name;
  }

  static inline struct kmem_cache *
  cache_from_memcg_idx(struct kmem_cache *s, int idx)

  {
  	return NULL;
  }

  
  static inline struct kmem_cache *memcg_root_cache(struct kmem_cache *s)
  {
  	return s;
  }

  
  static inline int memcg_charge_slab(struct kmem_cache *s, gfp_t gfp, int order)
  {
  	return 0;
  }
  
  static inline void memcg_uncharge_slab(struct kmem_cache *s, int order)
  {
  }

  
  static inline void slab_init_memcg_params(struct kmem_cache *s)
  {
  }
  #endif /* CONFIG_MEMCG_KMEM */

  
  static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x)
  {
  	struct kmem_cache *cachep;
  	struct page *page;
  
  	/*
  	 * When kmemcg is not being used, both assignments should return the
  	 * same value. but we don't want to pay the assignment price in that
  	 * case. If it is not compiled in, the compiler should be smart enough
  	 * to not do even the assignment. In that case, slab_equal_or_root
  	 * will also be a constant.
  	 */
  	if (!memcg_kmem_enabled() && !unlikely(s->flags & SLAB_DEBUG_FREE))
  		return s;
  
  	page = virt_to_head_page(x);
  	cachep = page->slab_cache;
  	if (slab_equal_or_root(cachep, s))
  		return cachep;
  
  	pr_err("%s: Wrong slab cache. %s but object is from %s
  ",

  	       __func__, cachep->name, s->name);

  	WARN_ON_ONCE(1);
  	return s;
  }

  #ifndef CONFIG_SLOB

  /*
   * The slab lists for all objects.
   */
  struct kmem_cache_node {
  	spinlock_t list_lock;
  
  #ifdef CONFIG_SLAB
  	struct list_head slabs_partial;	/* partial list first, better asm code */
  	struct list_head slabs_full;
  	struct list_head slabs_free;
  	unsigned long free_objects;
  	unsigned int free_limit;
  	unsigned int colour_next;	/* Per-node cache coloring */
  	struct array_cache *shared;	/* shared per node */

  	struct alien_cache **alien;	/* on other nodes */

  	unsigned long next_reap;	/* updated without locking */
  	int free_touched;		/* updated without locking */
  #endif
  
  #ifdef CONFIG_SLUB
  	unsigned long nr_partial;
  	struct list_head partial;
  #ifdef CONFIG_SLUB_DEBUG
  	atomic_long_t nr_slabs;
  	atomic_long_t total_objects;
  	struct list_head full;
  #endif
  #endif
  
  };

  static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node)
  {
  	return s->node[node];
  }
  
  /*
   * Iterator over all nodes. The body will be executed for each node that has
   * a kmem_cache_node structure allocated (which is true for all online nodes)
   */
  #define for_each_kmem_cache_node(__s, __node, __n) \

  	for (__node = 0; __node < nr_node_ids; __node++) \
  		 if ((__n = get_node(__s, __node)))

  
  #endif

  void *slab_start(struct seq_file *m, loff_t *pos);

  void *slab_next(struct seq_file *m, void *p, loff_t *pos);
  void slab_stop(struct seq_file *m, void *p);

  int memcg_slab_show(struct seq_file *m, void *p);

  
  #endif /* MM_SLAB_H */