Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef IOU_ALLOC_CACHE_H
3#define IOU_ALLOC_CACHE_H
4
5#include <linux/io_uring_types.h>
6#include <linux/kasan.h>
7
8/*
9 * Don't allow the cache to grow beyond this size.
10 */
11#define IO_ALLOC_CACHE_MAX 128
12
13void io_alloc_cache_free(struct io_alloc_cache *cache,
14 void (*free)(const void *));
15bool io_alloc_cache_init(struct io_alloc_cache *cache,
16 unsigned max_nr, unsigned int size,
17 unsigned int init_bytes);
18
19void *io_cache_alloc_new(struct io_alloc_cache *cache, gfp_t gfp);
20
21static inline bool io_alloc_cache_put(struct io_alloc_cache *cache,
22 void *entry)
23{
24 if (cache->nr_cached < cache->max_cached) {
25 if (!kasan_mempool_poison_object(entry))
26 return false;
27 cache->entries[cache->nr_cached++] = entry;
28 return true;
29 }
30 return false;
31}
32
33static inline void *io_alloc_cache_get(struct io_alloc_cache *cache)
34{
35 if (cache->nr_cached) {
36 void *entry = cache->entries[--cache->nr_cached];
37
38 /*
39 * If KASAN is enabled, always clear the initial bytes that
40 * must be zeroed post alloc, in case any of them overlap
41 * with KASAN storage.
42 */
43#if defined(CONFIG_KASAN)
44 kasan_mempool_unpoison_object(entry, cache->elem_size);
45 if (cache->init_clear)
46 memset(entry, 0, cache->init_clear);
47#endif
48 return entry;
49 }
50
51 return NULL;
52}
53
54static inline void *io_cache_alloc(struct io_alloc_cache *cache, gfp_t gfp)
55{
56 void *obj;
57
58 obj = io_alloc_cache_get(cache);
59 if (obj)
60 return obj;
61 return io_cache_alloc_new(cache, gfp);
62}
63
64static inline void io_cache_free(struct io_alloc_cache *cache, void *obj)
65{
66 if (!io_alloc_cache_put(cache, obj))
67 kfree(obj);
68}
69
70#endif