io_uring/alloc_cache.h

   1 #ifndef IOU_ALLOC_CACHE_H
   2 #define IOU_ALLOC_CACHE_H
   3
   4 /*
   5  * Don't allow the cache to grow beyond this size.
   6  */
   7 #define IO_ALLOC_CACHE_MAX      128
   8
   9 static inline bool io_alloc_cache_put(struct io_alloc_cache *cache,
  10                                       void *entry)
  11 {
  12         if (cache->nr_cached < cache->max_cached) {
  13                 if (!kasan_mempool_poison_object(entry))
  14                         return false;
  15                 cache->entries[cache->nr_cached++] = entry;
  16                 return true;
  17         }
  18         return false;
  19 }
  20
  21 static inline void *io_alloc_cache_get(struct io_alloc_cache *cache)
  22 {
  23         if (cache->nr_cached) {
  24                 void *entry = cache->entries[--cache->nr_cached];
  25
  26                 kasan_mempool_unpoison_object(entry, cache->elem_size);
  27                 return entry;
  28         }
  29
  30         return NULL;
  31 }
  32
  33 /* returns false if the cache was initialized properly */
  34 static inline bool io_alloc_cache_init(struct io_alloc_cache *cache,
  35                                        unsigned max_nr, size_t size)
  36 {
  37         cache->entries = kvmalloc_array(max_nr, sizeof(void *), GFP_KERNEL);
  38         if (cache->entries) {
  39                 cache->nr_cached = 0;
  40                 cache->max_cached = max_nr;
  41                 cache->elem_size = size;
  42                 return false;
  43         }
  44         return true;
  45 }
  46
  47 static inline void io_alloc_cache_free(struct io_alloc_cache *cache,
  48                                        void (*free)(const void *))
  49 {
  50         void *entry;
  51
  52         if (!cache->entries)
  53                 return;
  54
  55         while ((entry = io_alloc_cache_get(cache)) != NULL)
  56                 free(entry);
  57
  58         kvfree(cache->entries);
  59         cache->entries = NULL;
  60 }
  61 #endif