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|
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef MM_SLAB_H
#define MM_SLAB_H
/*
* Internal slab definitions
*/
/* Reuses the bits in struct page */
struct slab {
unsigned long __page_flags;
#if defined(CONFIG_SLAB)
union {
struct list_head slab_list;
struct rcu_head rcu_head;
};
struct kmem_cache *slab_cache;
void *freelist; /* array of free object indexes */
void *s_mem; /* first object */
unsigned int active;
#elif defined(CONFIG_SLUB)
union {
struct list_head slab_list;
struct rcu_head rcu_head;
#ifdef CONFIG_SLUB_CPU_PARTIAL
struct {
struct slab *next;
int slabs; /* Nr of slabs left */
};
#endif
};
struct kmem_cache *slab_cache;
/* Double-word boundary */
void *freelist; /* first free object */
union {
unsigned long counters;
struct {
unsigned inuse:16;
unsigned objects:15;
unsigned frozen:1;
};
};
unsigned int __unused;
#elif defined(CONFIG_SLOB)
struct list_head slab_list;
void *__unused_1;
void *freelist; /* first free block */
long units;
unsigned int __unused_2;
#else
#error "Unexpected slab allocator configured"
#endif
atomic_t __page_refcount;
#ifdef CONFIG_MEMCG
unsigned long memcg_data;
#endif
};
#define SLAB_MATCH(pg, sl) \
static_assert(offsetof(struct page, pg) == offsetof(struct slab, sl))
SLAB_MATCH(flags, __page_flags);
SLAB_MATCH(compound_head, slab_list); /* Ensure bit 0 is clear */
#ifndef CONFIG_SLOB
SLAB_MATCH(rcu_head, rcu_head);
#endif
SLAB_MATCH(_refcount, __page_refcount);
#ifdef CONFIG_MEMCG
SLAB_MATCH(memcg_data, memcg_data);
#endif
#undef SLAB_MATCH
static_assert(sizeof(struct slab) <= sizeof(struct page));
/**
* folio_slab - Converts from folio to slab.
* @folio: The folio.
*
* Currently struct slab is a different representation of a folio where
* folio_test_slab() is true.
*
* Return: The slab which contains this folio.
*/
#define folio_slab(folio) (_Generic((folio), \
const struct folio *: (const struct slab *)(folio), \
struct folio *: (struct slab *)(folio)))
/**
* slab_folio - The folio allocated for a slab
* @slab: The slab.
*
* Slabs are allocated as folios that contain the individual objects and are
* using some fields in the first struct page of the folio - those fields are
* now accessed by struct slab. It is occasionally necessary to convert back to
* a folio in order to communicate with the rest of the mm. Please use this
* helper function instead of casting yourself, as the implementation may change
* in the future.
*/
#define slab_folio(s) (_Generic((s), \
const struct slab *: (const struct folio *)s, \
struct slab *: (struct folio *)s))
/**
* page_slab - Converts from first struct page to slab.
* @p: The first (either head of compound or single) page of slab.
*
* A temporary wrapper to convert struct page to struct slab in situations where
* we know the page is the compound head, or single order-0 page.
*
* Long-term ideally everything would work with struct slab directly or go
* through folio to struct slab.
*
* Return: The slab which contains this page
*/
#define page_slab(p) (_Generic((p), \
const struct page *: (const struct slab *)(p), \
struct page *: (struct slab *)(p)))
/**
* slab_page - The first struct page allocated for a slab
* @slab: The slab.
*
* A convenience wrapper for converting slab to the first struct page of the
* underlying folio, to communicate with code not yet converted to folio or
* struct slab.
*/
#define slab_page(s) folio_page(slab_folio(s), 0)
/*
* If network-based swap is enabled, sl*b must keep track of whether pages
* were allocated from pfmemalloc reserves.
*/
static inline bool slab_test_pfmemalloc(const struct slab *slab)
{
return folio_test_active((struct folio *)slab_folio(slab));
}
static inline void slab_set_pfmemalloc(struct slab *slab)
{
folio_set_active(slab_folio(slab));
}
static inline void slab_clear_pfmemalloc(struct slab *slab)
{
folio_clear_active(slab_folio(slab));
}
static inline void __slab_clear_pfmemalloc(struct slab *slab)
{
__folio_clear_active(slab_folio(slab));
}
static inline void *slab_address(const struct slab *slab)
{
return folio_address(slab_folio(slab));
}
static inline int slab_nid(const struct slab *slab)
{
return folio_nid(slab_folio(slab));
}
static inline pg_data_t *slab_pgdat(const struct slab *slab)
{
return folio_pgdat(slab_folio(slab));
}
static inline struct slab *virt_to_slab(const void *addr)
{
struct folio *folio = virt_to_folio(addr);
if (!folio_test_slab(folio))
return NULL;
return folio_slab(folio);
}
static inline int slab_order(const struct slab *slab)
{
return folio_order((struct folio *)slab_folio(slab));
}
static inline size_t slab_size(const struct slab *slab)
{
return PAGE_SIZE << slab_order(slab);
}
#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>
#include <linux/list_lru.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);
void *__kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags,
int node, size_t orig_size,
unsigned long caller);
void __kmem_cache_free(struct kmem_cache *s, void *x, unsigned long caller);
#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);
#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)
{
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 | SLAB_NO_USER_FLAGS)
#else
#define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE)
#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 | \
SLAB_NO_USER_FLAGS)
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);
static inline enum node_stat_item 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);
long validate_slab_cache(struct kmem_cache *s);
static inline bool __slub_debug_enabled(void)
{
return static_branch_unlikely(&slub_debug_enabled);
}
#else
static inline void print_tracking(struct kmem_cache *s, void *object)
{
}
static inline bool __slub_debug_enabled(void)
{
return false;
}
#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)
{
if (IS_ENABLED(CONFIG_SLUB_DEBUG))
VM_WARN_ON_ONCE(!(flags & SLAB_DEBUG_FLAGS));
if (__slub_debug_enabled())
return s->flags & flags;
return false;
}
#ifdef CONFIG_MEMCG_KMEM
/*
* slab_objcgs - get the object cgroups vector associated with a slab
* @slab: a pointer to the slab struct
*
* Returns a pointer to the object cgroups vector associated with the slab,
* or NULL if no such vector has been associated yet.
*/
static inline struct obj_cgroup **slab_objcgs(struct slab *slab)
{
unsigned long memcg_data = READ_ONCE(slab->memcg_data);
VM_BUG_ON_PAGE(memcg_data && !(memcg_data & MEMCG_DATA_OBJCGS),
slab_page(slab));
VM_BUG_ON_PAGE(memcg_data & MEMCG_DATA_KMEM, slab_page(slab));
return (struct obj_cgroup **)(memcg_data & ~MEMCG_DATA_FLAGS_MASK);
}
int memcg_alloc_slab_cgroups(struct slab *slab, struct kmem_cache *s,
gfp_t gfp, bool new_slab);
void mod_objcg_state(struct obj_cgroup *objcg, struct pglist_data *pgdat,
enum node_stat_item idx, int nr);
static inline void memcg_free_slab_cgroups(struct slab *slab)
{
kfree(slab_objcgs(slab));
slab->memcg_data = 0;
}
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 list_lru *lru,
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 (lru) {
int ret;
struct mem_cgroup *memcg;
memcg = get_mem_cgroup_from_objcg(objcg);
ret = memcg_list_lru_alloc(memcg, lru, flags);
css_put(&memcg->css);
if (ret)
goto out;
}
if (obj_cgroup_charge(objcg, flags, objects * obj_full_size(s)))
goto out;
*objcgp = objcg;
return true;
out:
obj_cgroup_put(objcg);
return false;
}
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 slab *slab;
unsigned long off;
size_t i;
if (!memcg_kmem_enabled() || !objcg)
return;
for (i = 0; i < size; i++) {
if (likely(p[i])) {
slab = virt_to_slab(p[i]);
if (!slab_objcgs(slab) &&
memcg_alloc_slab_cgroups(slab, s, flags,
false)) {
obj_cgroup_uncharge(objcg, obj_full_size(s));
continue;
}
off = obj_to_index(s, slab, p[i]);
obj_cgroup_get(objcg);
slab_objcgs(slab)[off] = objcg;
mod_objcg_state(objcg, slab_pgdat(slab),
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, struct slab *slab,
void **p, int objects)
{
struct obj_cgroup **objcgs;
int i;
if (!memcg_kmem_enabled())
return;
objcgs = slab_objcgs(slab);
if (!objcgs)
return;
for (i = 0; i < objects; i++) {
struct obj_cgroup *objcg;
unsigned int off;
off = obj_to_index(s, slab, p[i]);
objcg = objcgs[off];
if (!objcg)
continue;
objcgs[off] = NULL;
obj_cgroup_uncharge(objcg, obj_full_size(s));
mod_objcg_state(objcg, slab_pgdat(slab), cache_vmstat_idx(s),
-obj_full_size(s));
obj_cgroup_put(objcg);
}
}
#else /* CONFIG_MEMCG_KMEM */
static inline struct obj_cgroup **slab_objcgs(struct slab *slab)
{
return NULL;
}
static inline struct mem_cgroup *memcg_from_slab_obj(void *ptr)
{
return NULL;
}
static inline int memcg_alloc_slab_cgroups(struct slab *slab,
struct kmem_cache *s, gfp_t gfp,
bool new_slab)
{
return 0;
}
static inline void memcg_free_slab_cgroups(struct slab *slab)
{
}
static inline bool memcg_slab_pre_alloc_hook(struct kmem_cache *s,
struct list_lru *lru,
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, struct slab *slab,
void **p, int objects)
{
}
#endif /* CONFIG_MEMCG_KMEM */
#ifndef CONFIG_SLOB
static inline struct kmem_cache *virt_to_cache(const void *obj)
{
struct slab *slab;
slab = virt_to_slab(obj);
if (WARN_ONCE(!slab, "%s: Object is not a Slab page!\n",
__func__))
return NULL;
return slab->slab_cache;
}
static __always_inline void account_slab(struct slab *slab, int order,
struct kmem_cache *s, gfp_t gfp)
{
if (memcg_kmem_enabled() && (s->flags & SLAB_ACCOUNT))
memcg_alloc_slab_cgroups(slab, s, gfp, true);
mod_node_page_state(slab_pgdat(slab), cache_vmstat_idx(s),
PAGE_SIZE << order);
}
static __always_inline void unaccount_slab(struct slab *slab, int order,
struct kmem_cache *s)
{
if (memcg_kmem_enabled())
memcg_free_slab_cgroups(slab);
mod_node_page_state(slab_pgdat(slab), 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\n",
__func__, s->name, cachep->name))
print_tracking(cachep, x);
return cachep;
}
void free_large_kmalloc(struct folio *folio, void *object);
#endif /* CONFIG_SLOB */
size_t __ksize(const void *objp);
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 list_lru *lru,
struct obj_cgroup **objcgp,
size_t size, gfp_t flags)
{
flags &= gfp_allowed_mask;
might_alloc(flags);
if (should_failslab(s, flags))
return NULL;
if (!memcg_slab_pre_alloc_hook(s, lru, 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, bool init)
{
size_t i;
flags &= gfp_allowed_mask;
/*
* As memory initialization might be integrated into KASAN,
* kasan_slab_alloc and initialization memset must be
* kept together to avoid discrepancies in behavior.
*
* As p[i] might get tagged, memset and kmemleak hook come after KASAN.
*/
for (i = 0; i < size; i++) {
p[i] = kasan_slab_alloc(s, p[i], flags, init);
if (p[i] && init && !kasan_has_integrated_init())
memset(p[i], 0, s->object_size);
kmemleak_alloc_recursive(p[i], s->object_size, 1,
s->flags, flags);
kmsan_slab_alloc(s, p[i], flags);
}
memcg_slab_post_alloc_hook(s, objcg, flags, size, p);
}
#ifndef CONFIG_SLOB
/*
* The slab lists for all objects.
*/
struct kmem_cache_node {
#ifdef CONFIG_SLAB
raw_spinlock_t list_lock;
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
spinlock_t list_lock;
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
#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_maybe(CONFIG_INIT_ON_ALLOC_DEFAULT_ON,
&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_maybe(CONFIG_INIT_ON_FREE_DEFAULT_ON,
&init_on_free))
return !(c->ctor ||
(c->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_POISON)));
return false;
}
#if defined(CONFIG_DEBUG_FS) && defined(CONFIG_SLUB_DEBUG)
void debugfs_slab_release(struct kmem_cache *);
#else
static inline void debugfs_slab_release(struct kmem_cache *s) { }
#endif
#ifdef CONFIG_PRINTK
#define KS_ADDRS_COUNT 16
struct kmem_obj_info {
void *kp_ptr;
struct slab *kp_slab;
void *kp_objp;
unsigned long kp_data_offset;
struct kmem_cache *kp_slab_cache;
void *kp_ret;
void *kp_stack[KS_ADDRS_COUNT];
void *kp_free_stack[KS_ADDRS_COUNT];
};
void __kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab *slab);
#endif
#ifdef CONFIG_HAVE_HARDENED_USERCOPY_ALLOCATOR
void __check_heap_object(const void *ptr, unsigned long n,
const struct slab *slab, bool to_user);
#else
static inline
void __check_heap_object(const void *ptr, unsigned long n,
const struct slab *slab, bool to_user)
{
}
#endif
#endif /* MM_SLAB_H */
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