Branch data     Line data    Source code

       1                 :            : /* SPDX-License-Identifier: GPL-2.0 */
       2                 :            : #ifndef _LINUX_SLUB_DEF_H
       3                 :            : #define _LINUX_SLUB_DEF_H
       4                 :            : 
       5                 :            : /*
       6                 :            :  * SLUB : A Slab allocator without object queues.
       7                 :            :  *
       8                 :            :  * (C) 2007 SGI, Christoph Lameter
       9                 :            :  */
      10                 :            : #include <linux/kobject.h>
      11                 :            : 
      12                 :            : enum stat_item {
      13                 :            :         ALLOC_FASTPATH,         /* Allocation from cpu slab */
      14                 :            :         ALLOC_SLOWPATH,         /* Allocation by getting a new cpu slab */
      15                 :            :         FREE_FASTPATH,          /* Free to cpu slab */
      16                 :            :         FREE_SLOWPATH,          /* Freeing not to cpu slab */
      17                 :            :         FREE_FROZEN,            /* Freeing to frozen slab */
      18                 :            :         FREE_ADD_PARTIAL,       /* Freeing moves slab to partial list */
      19                 :            :         FREE_REMOVE_PARTIAL,    /* Freeing removes last object */
      20                 :            :         ALLOC_FROM_PARTIAL,     /* Cpu slab acquired from node partial list */
      21                 :            :         ALLOC_SLAB,             /* Cpu slab acquired from page allocator */
      22                 :            :         ALLOC_REFILL,           /* Refill cpu slab from slab freelist */
      23                 :            :         ALLOC_NODE_MISMATCH,    /* Switching cpu slab */
      24                 :            :         FREE_SLAB,              /* Slab freed to the page allocator */
      25                 :            :         CPUSLAB_FLUSH,          /* Abandoning of the cpu slab */
      26                 :            :         DEACTIVATE_FULL,        /* Cpu slab was full when deactivated */
      27                 :            :         DEACTIVATE_EMPTY,       /* Cpu slab was empty when deactivated */
      28                 :            :         DEACTIVATE_TO_HEAD,     /* Cpu slab was moved to the head of partials */
      29                 :            :         DEACTIVATE_TO_TAIL,     /* Cpu slab was moved to the tail of partials */
      30                 :            :         DEACTIVATE_REMOTE_FREES,/* Slab contained remotely freed objects */
      31                 :            :         DEACTIVATE_BYPASS,      /* Implicit deactivation */
      32                 :            :         ORDER_FALLBACK,         /* Number of times fallback was necessary */
      33                 :            :         CMPXCHG_DOUBLE_CPU_FAIL,/* Failure of this_cpu_cmpxchg_double */
      34                 :            :         CMPXCHG_DOUBLE_FAIL,    /* Number of times that cmpxchg double did not match */
      35                 :            :         CPU_PARTIAL_ALLOC,      /* Used cpu partial on alloc */
      36                 :            :         CPU_PARTIAL_FREE,       /* Refill cpu partial on free */
      37                 :            :         CPU_PARTIAL_NODE,       /* Refill cpu partial from node partial */
      38                 :            :         CPU_PARTIAL_DRAIN,      /* Drain cpu partial to node partial */
      39                 :            :         NR_SLUB_STAT_ITEMS };
      40                 :            : 
      41                 :            : struct kmem_cache_cpu {
      42                 :            :         void **freelist;        /* Pointer to next available object */
      43                 :            :         unsigned long tid;      /* Globally unique transaction id */
      44                 :            :         struct page *page;      /* The slab from which we are allocating */
      45                 :            : #ifdef CONFIG_SLUB_CPU_PARTIAL
      46                 :            :         struct page *partial;   /* Partially allocated frozen slabs */
      47                 :            : #endif
      48                 :            : #ifdef CONFIG_SLUB_STATS
      49                 :            :         unsigned stat[NR_SLUB_STAT_ITEMS];
      50                 :            : #endif
      51                 :            : };
      52                 :            : 
      53                 :            : #ifdef CONFIG_SLUB_CPU_PARTIAL
      54                 :            : #define slub_percpu_partial(c)          ((c)->partial)
      55                 :            : 
      56                 :            : #define slub_set_percpu_partial(c, p)           \
      57                 :            : ({                                              \
      58                 :            :         slub_percpu_partial(c) = (p)->next;  \
      59                 :            : })
      60                 :            : 
      61                 :            : #define slub_percpu_partial_read_once(c)     READ_ONCE(slub_percpu_partial(c))
      62                 :            : #else
      63                 :            : #define slub_percpu_partial(c)                  NULL
      64                 :            : 
      65                 :            : #define slub_set_percpu_partial(c, p)
      66                 :            : 
      67                 :            : #define slub_percpu_partial_read_once(c)        NULL
      68                 :            : #endif // CONFIG_SLUB_CPU_PARTIAL
      69                 :            : 
      70                 :            : /*
      71                 :            :  * Word size structure that can be atomically updated or read and that
      72                 :            :  * contains both the order and the number of objects that a slab of the
      73                 :            :  * given order would contain.
      74                 :            :  */
      75                 :            : struct kmem_cache_order_objects {
      76                 :            :         unsigned int x;
      77                 :            : };
      78                 :            : 
      79                 :            : /*
      80                 :            :  * Slab cache management.
      81                 :            :  */
      82                 :            : struct kmem_cache {
      83                 :            :         struct kmem_cache_cpu __percpu *cpu_slab;
      84                 :            :         /* Used for retrieving partial slabs, etc. */
      85                 :            :         slab_flags_t flags;
      86                 :            :         unsigned long min_partial;
      87                 :            :         unsigned int size;      /* The size of an object including metadata */
      88                 :            :         unsigned int object_size;/* The size of an object without metadata */
      89                 :            :         unsigned int offset;    /* Free pointer offset */
      90                 :            : #ifdef CONFIG_SLUB_CPU_PARTIAL
      91                 :            :         /* Number of per cpu partial objects to keep around */
      92                 :            :         unsigned int cpu_partial;
      93                 :            : #endif
      94                 :            :         struct kmem_cache_order_objects oo;
      95                 :            : 
      96                 :            :         /* Allocation and freeing of slabs */
      97                 :            :         struct kmem_cache_order_objects max;
      98                 :            :         struct kmem_cache_order_objects min;
      99                 :            :         gfp_t allocflags;       /* gfp flags to use on each alloc */
     100                 :            :         int refcount;           /* Refcount for slab cache destroy */
     101                 :            :         void (*ctor)(void *);
     102                 :            :         unsigned int inuse;             /* Offset to metadata */
     103                 :            :         unsigned int align;             /* Alignment */
     104                 :            :         unsigned int red_left_pad;      /* Left redzone padding size */
     105                 :            :         const char *name;       /* Name (only for display!) */
     106                 :            :         struct list_head list;  /* List of slab caches */
     107                 :            : #ifdef CONFIG_SYSFS
     108                 :            :         struct kobject kobj;    /* For sysfs */
     109                 :            :         struct work_struct kobj_remove_work;
     110                 :            : #endif
     111                 :            : #ifdef CONFIG_MEMCG
     112                 :            :         struct memcg_cache_params memcg_params;
     113                 :            :         /* For propagation, maximum size of a stored attr */
     114                 :            :         unsigned int max_attr_size;
     115                 :            : #ifdef CONFIG_SYSFS
     116                 :            :         struct kset *memcg_kset;
     117                 :            : #endif
     118                 :            : #endif
     119                 :            : 
     120                 :            : #ifdef CONFIG_SLAB_FREELIST_HARDENED
     121                 :            :         unsigned long random;
     122                 :            : #endif
     123                 :            : 
     124                 :            : #ifdef CONFIG_NUMA
     125                 :            :         /*
     126                 :            :          * Defragmentation by allocating from a remote node.
     127                 :            :          */
     128                 :            :         unsigned int remote_node_defrag_ratio;
     129                 :            : #endif
     130                 :            : 
     131                 :            : #ifdef CONFIG_SLAB_FREELIST_RANDOM
     132                 :            :         unsigned int *random_seq;
     133                 :            : #endif
     134                 :            : 
     135                 :            : #ifdef CONFIG_KASAN
     136                 :            :         struct kasan_cache kasan_info;
     137                 :            : #endif
     138                 :            : 
     139                 :            :         unsigned int useroffset;        /* Usercopy region offset */
     140                 :            :         unsigned int usersize;          /* Usercopy region size */
     141                 :            : 
     142                 :            :         struct kmem_cache_node *node[MAX_NUMNODES];
     143                 :            : };
     144                 :            : 
     145                 :            : #ifdef CONFIG_SLUB_CPU_PARTIAL
     146                 :            : #define slub_cpu_partial(s)             ((s)->cpu_partial)
     147                 :            : #define slub_set_cpu_partial(s, n)              \
     148                 :            : ({                                              \
     149                 :            :         slub_cpu_partial(s) = (n);              \
     150                 :            : })
     151                 :            : #else
     152                 :            : #define slub_cpu_partial(s)             (0)
     153                 :            : #define slub_set_cpu_partial(s, n)
     154                 :            : #endif /* CONFIG_SLUB_CPU_PARTIAL */
     155                 :            : 
     156                 :            : #ifdef CONFIG_SYSFS
     157                 :            : #define SLAB_SUPPORTS_SYSFS
     158                 :            : void sysfs_slab_unlink(struct kmem_cache *);
     159                 :            : void sysfs_slab_release(struct kmem_cache *);
     160                 :            : #else
     161                 :            : static inline void sysfs_slab_unlink(struct kmem_cache *s)
     162                 :            : {
     163                 :            : }
     164                 :            : static inline void sysfs_slab_release(struct kmem_cache *s)
     165                 :            : {
     166                 :            : }
     167                 :            : #endif
     168                 :            : 
     169                 :            : void object_err(struct kmem_cache *s, struct page *page,
     170                 :            :                 u8 *object, char *reason);
     171                 :            : 
     172                 :            : void *fixup_red_left(struct kmem_cache *s, void *p);
     173                 :            : 
     174                 :    1915381 : static inline void *nearest_obj(struct kmem_cache *cache, struct page *page,
     175                 :            :                                 void *x) {
     176         [ +  - ]:    1915381 :         void *object = x - (x - page_address(page)) % cache->size;
     177                 :    1915381 :         void *last_object = page_address(page) +
     178                 :    1915381 :                 (page->objects - 1) * cache->size;
     179         [ +  - ]:    1915381 :         void *result = (unlikely(object > last_object)) ? last_object : object;
     180                 :            : 
     181                 :    1915381 :         result = fixup_red_left(cache, result);
     182                 :    1915381 :         return result;
     183                 :            : }
     184                 :            : 
     185                 :            : #endif /* _LINUX_SLUB_DEF_H */