908 static inline void cache_init(struct gnttab_page_cache *cache)  in cache_init()  argument
910 	cache->pages = NULL;  in cache_init()
913 static inline bool cache_empty(struct gnttab_page_cache *cache)  in cache_empty()  argument
915 	return !cache->pages;  in cache_empty()
918 static inline struct page *cache_deq(struct gnttab_page_cache *cache)  in cache_deq()  argument
922 	page = cache->pages;  in cache_deq()
923 	cache->pages = page->zone_device_data;  in cache_deq()
928 static inline void cache_enq(struct gnttab_page_cache *cache, struct page *page)  in cache_enq()  argument
930 	page->zone_device_data = cache->pages;  in cache_enq()
931 	cache->pages = page;  in cache_enq()
934 static inline void cache_init(struct gnttab_page_cache *cache)  in cache_init()  argument
936 	INIT_LIST_HEAD(&cache->pages);  in cache_init()
939 static inline bool cache_empty(struct gnttab_page_cache *cache)  in cache_empty()  argument
941 	return list_empty(&cache->pages);  in cache_empty()
944 static inline struct page *cache_deq(struct gnttab_page_cache *cache)  in cache_deq()  argument
948 	page = list_first_entry(&cache->pages, struct page, lru);  in cache_deq()
954 static inline void cache_enq(struct gnttab_page_cache *cache, struct page *page)  in cache_enq()  argument
956 	list_add(&page->lru, &cache->pages);  in cache_enq()
960 void gnttab_page_cache_init(struct gnttab_page_cache *cache)  in gnttab_page_cache_init()  argument
962 	spin_lock_init(&cache->lock);  in gnttab_page_cache_init()
963 	cache_init(cache);  in gnttab_page_cache_init()
964 	cache->num_pages = 0;  in gnttab_page_cache_init()
968 int gnttab_page_cache_get(struct gnttab_page_cache *cache, struct page **page)  in gnttab_page_cache_get()  argument
972 	spin_lock_irqsave(&cache->lock, flags);  in gnttab_page_cache_get()
974 	if (cache_empty(cache)) {  in gnttab_page_cache_get()
975 		spin_unlock_irqrestore(&cache->lock, flags);  in gnttab_page_cache_get()
979 	page[0] = cache_deq(cache);  in gnttab_page_cache_get()
980 	cache->num_pages--;  in gnttab_page_cache_get()
982 	spin_unlock_irqrestore(&cache->lock, flags);  in gnttab_page_cache_get()
988 void gnttab_page_cache_put(struct gnttab_page_cache *cache, struct page **page,  in gnttab_page_cache_put()  argument
994 	spin_lock_irqsave(&cache->lock, flags);  in gnttab_page_cache_put()
997 		cache_enq(cache, page[i]);  in gnttab_page_cache_put()
998 	cache->num_pages += num;  in gnttab_page_cache_put()
1000 	spin_unlock_irqrestore(&cache->lock, flags);  in gnttab_page_cache_put()
1004 void gnttab_page_cache_shrink(struct gnttab_page_cache *cache, unsigned int num)  in gnttab_page_cache_shrink()  argument
1010 	spin_lock_irqsave(&cache->lock, flags);  in gnttab_page_cache_shrink()
1012 	while (cache->num_pages > num) {  in gnttab_page_cache_shrink()
1013 		page[i] = cache_deq(cache);  in gnttab_page_cache_shrink()
1014 		cache->num_pages--;  in gnttab_page_cache_shrink()
1016 			spin_unlock_irqrestore(&cache->lock, flags);  in gnttab_page_cache_shrink()
1019 			spin_lock_irqsave(&cache->lock, flags);  in gnttab_page_cache_shrink()
1023 	spin_unlock_irqrestore(&cache->lock, flags);  in gnttab_page_cache_shrink()