1 files changed, 35 insertions, 25 deletions

diff --git a/io_uring/alloc_cache.h b/io_uring/alloc_cache.h
index b7a38a2069cf..0dd17d8ba93a 100644
--- a/io_uring/alloc_cache.h
+++ b/io_uring/alloc_cache.h
@@ -1,11 +1,30 @@
 #ifndef IOU_ALLOC_CACHE_H
 #define IOU_ALLOC_CACHE_H
 
+#include <linux/io_uring_types.h>
+
 /*
  * Don't allow the cache to grow beyond this size.
  */
 #define IO_ALLOC_CACHE_MAX	128
 
+void io_alloc_cache_free(struct io_alloc_cache *cache,
+			 void (*free)(const void *));
+bool io_alloc_cache_init(struct io_alloc_cache *cache,
+			 unsigned max_nr, unsigned int size,
+			 unsigned int init_bytes);
+
+void *io_cache_alloc_new(struct io_alloc_cache *cache, gfp_t gfp);
+
+static inline void io_alloc_cache_kasan(struct iovec **iov, int *nr)
+{
+	if (IS_ENABLED(CONFIG_KASAN)) {
+		kfree(*iov);
+		*iov = NULL;
+		*nr = 0;
+	}
+}
+
 static inline bool io_alloc_cache_put(struct io_alloc_cache *cache,
 				      void *entry)
 {
@@ -23,39 +42,30 @@ static inline void *io_alloc_cache_get(struct io_alloc_cache *cache)
 	if (cache->nr_cached) {
 		void *entry = cache->entries[--cache->nr_cached];
 
+		/*
+		 * If KASAN is enabled, always clear the initial bytes that
+		 * must be zeroed post alloc, in case any of them overlap
+		 * with KASAN storage.
+		 */
+#if defined(CONFIG_KASAN)
 		kasan_mempool_unpoison_object(entry, cache->elem_size);
+		if (cache->init_clear)
+			memset(entry, 0, cache->init_clear);
+#endif
 		return entry;
 	}
 
 	return NULL;
 }
 
-/* returns false if the cache was initialized properly */
-static inline bool io_alloc_cache_init(struct io_alloc_cache *cache,
-				       unsigned max_nr, size_t size)
+static inline void *io_cache_alloc(struct io_alloc_cache *cache, gfp_t gfp)
 {
-	cache->entries = kvmalloc_array(max_nr, sizeof(void *), GFP_KERNEL);
-	if (cache->entries) {
-		cache->nr_cached = 0;
-		cache->max_cached = max_nr;
-		cache->elem_size = size;
-		return false;
-	}
-	return true;
-}
-
-static inline void io_alloc_cache_free(struct io_alloc_cache *cache,
-				       void (*free)(const void *))
-{
-	void *entry;
+	void *obj;
 
-	if (!cache->entries)
-		return;
-
-	while ((entry = io_alloc_cache_get(cache)) != NULL)
-		free(entry);
-
-	kvfree(cache->entries);
-	cache->entries = NULL;
+	obj = io_alloc_cache_get(cache);
+	if (obj)
+		return obj;
+	return io_cache_alloc_new(cache, gfp);
 }
+
 #endif