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

  #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 */

  	slab_flags_t flags;	/* Active flags on the slab */

  	unsigned int useroffset;/* Usercopy region offset */
  	unsigned int usersize;	/* Usercopy region size */

  	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>

  #include <linux/fault-inject.h>

  #include <linux/kasan.h>
  #include <linux/kmemleak.h>

  #include <linux/random.h>

  #include <linux/sched/mm.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;

  /* A table of kmalloc cache names and sizes */
  extern const struct kmalloc_info_struct {

  	const char *name[NR_KMALLOC_TYPES];

  	unsigned int size;

  } kmalloc_info[];

  #ifndef CONFIG_SLOB
  /* Kmalloc array related functions */

  void setup_kmalloc_cache_index_table(void);

  void create_kmalloc_caches(slab_flags_t);

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

  #endif

  gfp_t kmalloc_fix_flags(gfp_t flags);

  /* Functions provided by the slab allocators */

  int __kmem_cache_create(struct kmem_cache *, slab_flags_t flags);

  struct kmem_cache *create_kmalloc_cache(const char *name, unsigned int size,
  			slab_flags_t flags, unsigned int useroffset,
  			unsigned int usersize);

  extern void create_boot_cache(struct kmem_cache *, const char *name,

  			unsigned int size, slab_flags_t flags,
  			unsigned int useroffset, unsigned int usersize);

  int slab_unmergeable(struct kmem_cache *s);

  struct kmem_cache *find_mergeable(unsigned size, unsigned align,

  		slab_flags_t flags, const char *name, void (*ctor)(void *));

  #ifndef CONFIG_SLOB

  struct kmem_cache *

  __kmem_cache_alias(const char *name, unsigned int size, unsigned int align,

  		   slab_flags_t flags, void (*ctor)(void *));

  slab_flags_t kmem_cache_flags(unsigned int object_size,

  	slab_flags_t flags, const char *name,

  	void (*ctor)(void *));

  #else

  static inline struct kmem_cache *

  __kmem_cache_alias(const char *name, unsigned int size, unsigned int align,

  		   slab_flags_t flags, void (*ctor)(void *))

  { return NULL; }

  static inline slab_flags_t kmem_cache_flags(unsigned int object_size,

  	slab_flags_t 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_CACHE_DMA32 | SLAB_PANIC | \

  			 SLAB_TYPESAFE_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_CONSISTENCY_CHECKS)

  #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_ACCOUNT)

  #elif defined(CONFIG_SLUB)
  #define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \

  			  SLAB_TEMPORARY | SLAB_ACCOUNT)

  #else
  #define SLAB_CACHE_FLAGS (0)
  #endif

  /* Common flags available with current configuration */

  #define CACHE_CREATE_MASK (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS | SLAB_CACHE_FLAGS)

  /* Common flags permitted for kmem_cache_create */
  #define SLAB_FLAGS_PERMITTED (SLAB_CORE_FLAGS | \
  			      SLAB_RED_ZONE | \
  			      SLAB_POISON | \
  			      SLAB_STORE_USER | \
  			      SLAB_TRACE | \
  			      SLAB_CONSISTENCY_CHECKS | \
  			      SLAB_MEM_SPREAD | \
  			      SLAB_NOLEAKTRACE | \
  			      SLAB_RECLAIM_ACCOUNT | \
  			      SLAB_TEMPORARY | \

  			      SLAB_ACCOUNT)

  bool __kmem_cache_empty(struct kmem_cache *);

  int __kmem_cache_shutdown(struct kmem_cache *);

  void __kmem_cache_release(struct kmem_cache *);

  int __kmem_cache_shrink(struct kmem_cache *);

  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);

  /*
   * Generic implementation of bulk operations
   * These are useful for situations in which the allocator cannot

   * perform optimizations. In that case segments of the object listed

   * may be allocated or freed using these operations.
   */
  void __kmem_cache_free_bulk(struct kmem_cache *, size_t, void **);

  int __kmem_cache_alloc_bulk(struct kmem_cache *, gfp_t, size_t, void **);

  static inline int cache_vmstat_idx(struct kmem_cache *s)
  {
  	return (s->flags & SLAB_RECLAIM_ACCOUNT) ?

  		NR_SLAB_RECLAIMABLE_B : NR_SLAB_UNRECLAIMABLE_B;

  }

  #ifdef CONFIG_SLUB_DEBUG
  #ifdef CONFIG_SLUB_DEBUG_ON
  DECLARE_STATIC_KEY_TRUE(slub_debug_enabled);
  #else
  DECLARE_STATIC_KEY_FALSE(slub_debug_enabled);
  #endif
  extern void print_tracking(struct kmem_cache *s, void *object);
  #else
  static inline void print_tracking(struct kmem_cache *s, void *object)
  {
  }
  #endif
  
  /*
   * Returns true if any of the specified slub_debug flags is enabled for the
   * cache. Use only for flags parsed by setup_slub_debug() as it also enables
   * the static key.
   */
  static inline bool kmem_cache_debug_flags(struct kmem_cache *s, slab_flags_t flags)
  {
  #ifdef CONFIG_SLUB_DEBUG
  	VM_WARN_ON_ONCE(!(flags & SLAB_DEBUG_FLAGS));
  	if (static_branch_unlikely(&slub_debug_enabled))
  		return s->flags & flags;
  #endif
  	return false;
  }

  #ifdef CONFIG_MEMCG_KMEM

  static inline struct obj_cgroup **page_obj_cgroups(struct page *page)
  {
  	/*
  	 * page->mem_cgroup and page->obj_cgroups are sharing the same
  	 * space. To distinguish between them in case we don't know for sure
  	 * that the page is a slab page (e.g. page_cgroup_ino()), let's
  	 * always set the lowest bit of obj_cgroups.
  	 */
  	return (struct obj_cgroup **)
  		((unsigned long)page->obj_cgroups & ~0x1UL);
  }

  static inline bool page_has_obj_cgroups(struct page *page)

  {

  	return ((unsigned long)page->obj_cgroups & 0x1UL);

  }

  int memcg_alloc_page_obj_cgroups(struct page *page, struct kmem_cache *s,
  				 gfp_t gfp);

  
  static inline void memcg_free_page_obj_cgroups(struct page *page)
  {
  	kfree(page_obj_cgroups(page));
  	page->obj_cgroups = NULL;
  }

  static inline size_t obj_full_size(struct kmem_cache *s)
  {
  	/*
  	 * For each accounted object there is an extra space which is used
  	 * to store obj_cgroup membership. Charge it too.
  	 */
  	return s->size + sizeof(struct obj_cgroup *);
  }

  /*
   * Returns false if the allocation should fail.
   */
  static inline bool memcg_slab_pre_alloc_hook(struct kmem_cache *s,
  					     struct obj_cgroup **objcgp,
  					     size_t objects, gfp_t flags)

  {

  	struct obj_cgroup *objcg;

  	if (!memcg_kmem_enabled())
  		return true;
  
  	if (!(flags & __GFP_ACCOUNT) && !(s->flags & SLAB_ACCOUNT))
  		return true;

  	objcg = get_obj_cgroup_from_current();
  	if (!objcg)

  		return true;

  
  	if (obj_cgroup_charge(objcg, flags, objects * obj_full_size(s))) {
  		obj_cgroup_put(objcg);

  		return false;

  	}

  	*objcgp = objcg;
  	return true;

  }
  
  static inline void mod_objcg_state(struct obj_cgroup *objcg,
  				   struct pglist_data *pgdat,
  				   int idx, int nr)
  {
  	struct mem_cgroup *memcg;
  	struct lruvec *lruvec;
  
  	rcu_read_lock();
  	memcg = obj_cgroup_memcg(objcg);
  	lruvec = mem_cgroup_lruvec(memcg, pgdat);
  	mod_memcg_lruvec_state(lruvec, idx, nr);
  	rcu_read_unlock();
  }

  static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s,
  					      struct obj_cgroup *objcg,

  					      gfp_t flags, size_t size,
  					      void **p)

  {
  	struct page *page;
  	unsigned long off;
  	size_t i;

  	if (!memcg_kmem_enabled() || !objcg)

  		return;
  
  	flags &= ~__GFP_ACCOUNT;

  	for (i = 0; i < size; i++) {
  		if (likely(p[i])) {
  			page = virt_to_head_page(p[i]);

  
  			if (!page_has_obj_cgroups(page) &&
  			    memcg_alloc_page_obj_cgroups(page, s, flags)) {
  				obj_cgroup_uncharge(objcg, obj_full_size(s));
  				continue;
  			}

  			off = obj_to_index(s, page, p[i]);
  			obj_cgroup_get(objcg);
  			page_obj_cgroups(page)[off] = objcg;

  			mod_objcg_state(objcg, page_pgdat(page),
  					cache_vmstat_idx(s), obj_full_size(s));
  		} else {
  			obj_cgroup_uncharge(objcg, obj_full_size(s));

  		}
  	}
  	obj_cgroup_put(objcg);

  }

  static inline void memcg_slab_free_hook(struct kmem_cache *s_orig,
  					void **p, int objects)

  {

  	struct kmem_cache *s;

  	struct obj_cgroup *objcg;

  	struct page *page;

  	unsigned int off;

  	int i;

  	if (!memcg_kmem_enabled())
  		return;

  	for (i = 0; i < objects; i++) {
  		if (unlikely(!p[i]))
  			continue;

  		page = virt_to_head_page(p[i]);
  		if (!page_has_obj_cgroups(page))
  			continue;

  		if (!s_orig)
  			s = page->slab_cache;
  		else
  			s = s_orig;

  		off = obj_to_index(s, page, p[i]);
  		objcg = page_obj_cgroups(page)[off];
  		if (!objcg)
  			continue;

  		page_obj_cgroups(page)[off] = NULL;
  		obj_cgroup_uncharge(objcg, obj_full_size(s));
  		mod_objcg_state(objcg, page_pgdat(page), cache_vmstat_idx(s),
  				-obj_full_size(s));
  		obj_cgroup_put(objcg);
  	}

  }

  #else /* CONFIG_MEMCG_KMEM */

  static inline bool page_has_obj_cgroups(struct page *page)
  {
  	return false;
  }
  
  static inline struct mem_cgroup *memcg_from_slab_obj(void *ptr)

  {
  	return NULL;
  }

  static inline int memcg_alloc_page_obj_cgroups(struct page *page,
  					       struct kmem_cache *s, gfp_t gfp)
  {
  	return 0;
  }
  
  static inline void memcg_free_page_obj_cgroups(struct page *page)
  {
  }

  static inline bool memcg_slab_pre_alloc_hook(struct kmem_cache *s,
  					     struct obj_cgroup **objcgp,
  					     size_t objects, gfp_t flags)

  {

  	return true;

  }

  static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s,
  					      struct obj_cgroup *objcg,

  					      gfp_t flags, size_t size,
  					      void **p)

  {
  }

  static inline void memcg_slab_free_hook(struct kmem_cache *s,
  					void **p, int objects)

  {
  }

  #endif /* CONFIG_MEMCG_KMEM */

  static inline struct kmem_cache *virt_to_cache(const void *obj)
  {
  	struct page *page;
  
  	page = virt_to_head_page(obj);
  	if (WARN_ONCE(!PageSlab(page), "%s: Object is not a Slab page!
  ",
  					__func__))
  		return NULL;
  	return page->slab_cache;
  }

  static __always_inline void account_slab_page(struct page *page, int order,
  					      struct kmem_cache *s)

  {

  	mod_node_page_state(page_pgdat(page), cache_vmstat_idx(s),
  			    PAGE_SIZE << order);

  }

  static __always_inline void unaccount_slab_page(struct page *page, int order,
  						struct kmem_cache *s)

  {

  	if (memcg_kmem_enabled())

  		memcg_free_page_obj_cgroups(page);

  	mod_node_page_state(page_pgdat(page), cache_vmstat_idx(s),
  			    -(PAGE_SIZE << order));

  }

  static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x)
  {
  	struct kmem_cache *cachep;
  
  	if (!IS_ENABLED(CONFIG_SLAB_FREELIST_HARDENED) &&

  	    !kmem_cache_debug_flags(s, SLAB_CONSISTENCY_CHECKS))
  		return s;
  
  	cachep = virt_to_cache(x);

  	if (WARN(cachep && cachep != s,

  		  "%s: Wrong slab cache. %s but object is from %s
  ",
  		  __func__, s->name, cachep->name))
  		print_tracking(cachep, x);
  	return cachep;
  }

  static inline size_t slab_ksize(const struct kmem_cache *s)
  {
  #ifndef CONFIG_SLUB
  	return s->object_size;
  
  #else /* CONFIG_SLUB */
  # ifdef CONFIG_SLUB_DEBUG
  	/*
  	 * Debugging requires use of the padding between object
  	 * and whatever may come after it.
  	 */
  	if (s->flags & (SLAB_RED_ZONE | SLAB_POISON))
  		return s->object_size;
  # endif

  	if (s->flags & SLAB_KASAN)
  		return s->object_size;

  	/*
  	 * If we have the need to store the freelist pointer
  	 * back there or track user information then we can
  	 * only use the space before that information.
  	 */

  	if (s->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_STORE_USER))

  		return s->inuse;
  	/*
  	 * Else we can use all the padding etc for the allocation
  	 */
  	return s->size;
  #endif
  }
  
  static inline struct kmem_cache *slab_pre_alloc_hook(struct kmem_cache *s,

  						     struct obj_cgroup **objcgp,
  						     size_t size, gfp_t flags)

  {
  	flags &= gfp_allowed_mask;

  
  	fs_reclaim_acquire(flags);
  	fs_reclaim_release(flags);

  	might_sleep_if(gfpflags_allow_blocking(flags));

  	if (should_failslab(s, flags))

  		return NULL;

  	if (!memcg_slab_pre_alloc_hook(s, objcgp, size, flags))
  		return NULL;

  
  	return s;

  }

  static inline void slab_post_alloc_hook(struct kmem_cache *s,
  					struct obj_cgroup *objcg,
  					gfp_t flags, size_t size, void **p)

  {
  	size_t i;
  
  	flags &= gfp_allowed_mask;
  	for (i = 0; i < size; i++) {

  		p[i] = kasan_slab_alloc(s, p[i], flags);

  		/* As p[i] might get tagged, call kmemleak hook after KASAN. */

  		kmemleak_alloc_recursive(p[i], s->object_size, 1,

  					 s->flags, flags);

  	}

  	memcg_slab_post_alloc_hook(s, objcg, flags, size, p);

  }

  #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 total_slabs;	/* length of all slab lists */
  	unsigned long free_slabs;	/* length of free slab list only */

  	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);

  #if defined(CONFIG_SLAB) || defined(CONFIG_SLUB_DEBUG)
  void dump_unreclaimable_slab(void);
  #else
  static inline void dump_unreclaimable_slab(void)
  {
  }
  #endif

  void ___cache_free(struct kmem_cache *cache, void *x, unsigned long addr);

  #ifdef CONFIG_SLAB_FREELIST_RANDOM
  int cache_random_seq_create(struct kmem_cache *cachep, unsigned int count,
  			gfp_t gfp);
  void cache_random_seq_destroy(struct kmem_cache *cachep);
  #else
  static inline int cache_random_seq_create(struct kmem_cache *cachep,
  					unsigned int count, gfp_t gfp)
  {
  	return 0;
  }
  static inline void cache_random_seq_destroy(struct kmem_cache *cachep) { }
  #endif /* CONFIG_SLAB_FREELIST_RANDOM */

  static inline bool slab_want_init_on_alloc(gfp_t flags, struct kmem_cache *c)
  {
  	if (static_branch_unlikely(&init_on_alloc)) {
  		if (c->ctor)
  			return false;
  		if (c->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_POISON))
  			return flags & __GFP_ZERO;
  		return true;
  	}
  	return flags & __GFP_ZERO;
  }
  
  static inline bool slab_want_init_on_free(struct kmem_cache *c)
  {
  	if (static_branch_unlikely(&init_on_free))
  		return !(c->ctor ||
  			 (c->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_POISON)));
  	return false;
  }

  #endif /* MM_SLAB_H */