linux/io_uring/alloc_cache.h

67 lines
1.4 KiB
C
Raw Normal View History

#ifndef IOU_ALLOC_CACHE_H
#define IOU_ALLOC_CACHE_H
/*
* Don't allow the cache to grow beyond this size.
*/
#define IO_ALLOC_CACHE_MAX 512
struct io_cache_entry {
struct io_wq_work_node node;
};
static inline bool io_alloc_cache_put(struct io_alloc_cache *cache,
struct io_cache_entry *entry)
{
if (cache->nr_cached < cache->max_cached) {
cache->nr_cached++;
wq_stack_add_head(&entry->node, &cache->list);
kasan: rename kasan_slab_free_mempool to kasan_mempool_poison_object Patch series "kasan: save mempool stack traces". This series updates KASAN to save alloc and free stack traces for secondary-level allocators that cache and reuse allocations internally instead of giving them back to the underlying allocator (e.g. mempool). As a part of this change, introduce and document a set of KASAN hooks: bool kasan_mempool_poison_pages(struct page *page, unsigned int order); void kasan_mempool_unpoison_pages(struct page *page, unsigned int order); bool kasan_mempool_poison_object(void *ptr); void kasan_mempool_unpoison_object(void *ptr, size_t size); and use them in the mempool code. Besides mempool, skbuff and io_uring also cache allocations and already use KASAN hooks to poison those. Their code is updated to use the new mempool hooks. The new hooks save alloc and free stack traces (for normal kmalloc and slab objects; stack traces for large kmalloc objects and page_alloc are not supported by KASAN yet), improve the readability of the users' code, and also allow the users to prevent double-free and invalid-free bugs; see the patches for the details. This patch (of 21): Rename kasan_slab_free_mempool to kasan_mempool_poison_object. kasan_slab_free_mempool is a slightly confusing name: it is unclear whether this function poisons the object when it is freed into mempool or does something when the object is freed from mempool to the underlying allocator. The new name also aligns with other mempool-related KASAN hooks added in the following patches in this series. Link: https://lkml.kernel.org/r/cover.1703024586.git.andreyknvl@google.com Link: https://lkml.kernel.org/r/c5618685abb7cdbf9fb4897f565e7759f601da84.1703024586.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Cc: Alexander Lobakin <alobakin@pm.me> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Breno Leitao <leitao@debian.org> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Evgenii Stepanov <eugenis@google.com> Cc: Marco Elver <elver@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-19 22:28:45 +00:00
kasan_mempool_poison_object(entry);
return true;
}
return false;
}
static inline bool io_alloc_cache_empty(struct io_alloc_cache *cache)
{
return !cache->list.next;
}
static inline struct io_cache_entry *io_alloc_cache_get(struct io_alloc_cache *cache)
{
if (cache->list.next) {
struct io_cache_entry *entry;
entry = container_of(cache->list.next, struct io_cache_entry, node);
kasan_mempool_unpoison_object(entry, cache->elem_size);
cache->list.next = cache->list.next->next;
cache->nr_cached--;
return entry;
}
return NULL;
}
static inline void io_alloc_cache_init(struct io_alloc_cache *cache,
unsigned max_nr, size_t size)
{
cache->list.next = NULL;
cache->nr_cached = 0;
cache->max_cached = max_nr;
cache->elem_size = size;
}
static inline void io_alloc_cache_free(struct io_alloc_cache *cache,
void (*free)(struct io_cache_entry *))
{
while (1) {
struct io_cache_entry *entry = io_alloc_cache_get(cache);
if (!entry)
break;
free(entry);
}
cache->nr_cached = 0;
}
#endif