63  * freelists maintained in each pool. NCHUNKS_ORDER of 6 means that the
67  * 63 freelists per pool.
77  * struct zbud_pool - stores metadata for each zbud pool
78  * @lock:	protects all pool fields and first|last_chunk fields of any
79  *		zbud page in the pool
87  * @pages_nr:	number of zbud pages in the pool.
89  *		pool creation time.
91  * This structure is allocated at pool creation time and maintains metadata
92  * pertaining to a particular zbud pool.
110  * @buddy:	links the zbud page into the unbuddied/buddied lists in the pool
111  * @lru:	links the zbud page into the lru list in the pool
129 static int zbud_zpool_evict(struct zbud_pool *pool, unsigned long handle)  in zbud_zpool_evict()  argument
131 	if (pool->zpool && pool->zpool_ops && pool->zpool_ops->evict)  in zbud_zpool_evict()
132 		return pool->zpool_ops->evict(pool->zpool, handle);  in zbud_zpool_evict()
145 	struct zbud_pool *pool;  in zbud_zpool_create()  local
147 	pool = zbud_create_pool(gfp, zpool_ops ? &zbud_zpool_ops : NULL);  in zbud_zpool_create()
148 	if (pool) {  in zbud_zpool_create()
149 		pool->zpool = zpool;  in zbud_zpool_create()
150 		pool->zpool_ops = zpool_ops;  in zbud_zpool_create()
152 	return pool;  in zbud_zpool_create()
155 static void zbud_zpool_destroy(void *pool)  in zbud_zpool_destroy()  argument
157 	zbud_destroy_pool(pool);  in zbud_zpool_destroy()
160 static int zbud_zpool_malloc(void *pool, size_t size, gfp_t gfp,  in zbud_zpool_malloc()  argument
163 	return zbud_alloc(pool, size, gfp, handle);  in zbud_zpool_malloc()
165 static void zbud_zpool_free(void *pool, unsigned long handle)  in zbud_zpool_free()  argument
167 	zbud_free(pool, handle);  in zbud_zpool_free()
170 static int zbud_zpool_shrink(void *pool, unsigned int pages,  in zbud_zpool_shrink()  argument
177 		ret = zbud_reclaim_page(pool, 8);  in zbud_zpool_shrink()
189 static void *zbud_zpool_map(void *pool, unsigned long handle,  in zbud_zpool_map()  argument
192 	return zbud_map(pool, handle);  in zbud_zpool_map()
194 static void zbud_zpool_unmap(void *pool, unsigned long handle)  in zbud_zpool_unmap()  argument
196 	zbud_unmap(pool, handle);  in zbud_zpool_unmap()
199 static u64 zbud_zpool_total_size(void *pool)  in zbud_zpool_total_size()  argument
201 	return zbud_get_pool_size(pool) * PAGE_SIZE;  in zbud_zpool_total_size()
258  * Pool lock should be held as this function accesses first|last_chunks
299  * zbud_create_pool() - create a new zbud pool
300  * @gfp:	gfp flags when allocating the zbud pool structure
301  * @ops:	user-defined operations for the zbud pool
303  * Return: pointer to the new zbud pool or NULL if the metadata allocation
308 	struct zbud_pool *pool;  in zbud_create_pool()  local
311 	pool = kzalloc(sizeof(struct zbud_pool), gfp);  in zbud_create_pool()
312 	if (!pool)  in zbud_create_pool()
314 	spin_lock_init(&pool->lock);  in zbud_create_pool()
316 		INIT_LIST_HEAD(&pool->unbuddied[i]);  in zbud_create_pool()
317 	INIT_LIST_HEAD(&pool->buddied);  in zbud_create_pool()
318 	INIT_LIST_HEAD(&pool->lru);  in zbud_create_pool()
319 	pool->pages_nr = 0;  in zbud_create_pool()
320 	pool->ops = ops;  in zbud_create_pool()
321 	return pool;  in zbud_create_pool()
325  * zbud_destroy_pool() - destroys an existing zbud pool
326  * @pool:	the zbud pool to be destroyed
328  * The pool should be emptied before this function is called.
330 void zbud_destroy_pool(struct zbud_pool *pool)  in zbud_destroy_pool()  argument
332 	kfree(pool);  in zbud_destroy_pool()
337  * @pool:	zbud pool from which to allocate
339  * @gfp:	gfp flags used if the pool needs to grow
342  * This function will attempt to find a free region in the pool large enough to
345  * allocated and added to the pool to satisfy the request.
348  * as zbud pool pages.
351  * gfp arguments are invalid or -ENOMEM if the pool was unable to allocate
354 int zbud_alloc(struct zbud_pool *pool, size_t size, gfp_t gfp,  in zbud_alloc()  argument
367 	spin_lock(&pool->lock);  in zbud_alloc()
371 		if (!list_empty(&pool->unbuddied[i])) {  in zbud_alloc()
372 			zhdr = list_first_entry(&pool->unbuddied[i],  in zbud_alloc()
384 	spin_unlock(&pool->lock);  in zbud_alloc()
388 	spin_lock(&pool->lock);  in zbud_alloc()
389 	pool->pages_nr++;  in zbud_alloc()
402 		list_add(&zhdr->buddy, &pool->unbuddied[freechunks]);  in zbud_alloc()
405 		list_add(&zhdr->buddy, &pool->buddied);  in zbud_alloc()
411 	list_add(&zhdr->lru, &pool->lru);  in zbud_alloc()
414 	spin_unlock(&pool->lock);  in zbud_alloc()
421  * @pool:	pool in which the allocation resided
429 void zbud_free(struct zbud_pool *pool, unsigned long handle)  in zbud_free()  argument
434 	spin_lock(&pool->lock);  in zbud_free()
445 		spin_unlock(&pool->lock);  in zbud_free()
456 		pool->pages_nr--;  in zbud_free()
460 		list_add(&zhdr->buddy, &pool->unbuddied[freechunks]);  in zbud_free()
463 	spin_unlock(&pool->lock);  in zbud_free()
467  * zbud_reclaim_page() - evicts allocations from a pool page and frees it
468  * @pool:	pool from which a page will attempt to be evicted
481  * zbud_reclaim_page() will remove a zbud page from the pool LRU list and call
482  * the user-defined eviction handler with the pool and handle as arguments.
501 int zbud_reclaim_page(struct zbud_pool *pool, unsigned int retries)  in zbud_reclaim_page()  argument
507 	spin_lock(&pool->lock);  in zbud_reclaim_page()
508 	if (!pool->ops || !pool->ops->evict || list_empty(&pool->lru) ||  in zbud_reclaim_page()
510 		spin_unlock(&pool->lock);  in zbud_reclaim_page()
514 		zhdr = list_last_entry(&pool->lru, struct zbud_header, lru);  in zbud_reclaim_page()
529 		spin_unlock(&pool->lock);  in zbud_reclaim_page()
533 			ret = pool->ops->evict(pool, first_handle);  in zbud_reclaim_page()
538 			ret = pool->ops->evict(pool, last_handle);  in zbud_reclaim_page()
543 		spin_lock(&pool->lock);  in zbud_reclaim_page()
551 			pool->pages_nr--;  in zbud_reclaim_page()
552 			spin_unlock(&pool->lock);  in zbud_reclaim_page()
558 			list_add(&zhdr->buddy, &pool->unbuddied[freechunks]);  in zbud_reclaim_page()
561 			list_add(&zhdr->buddy, &pool->buddied);  in zbud_reclaim_page()
565 		list_add(&zhdr->lru, &pool->lru);  in zbud_reclaim_page()
567 	spin_unlock(&pool->lock);  in zbud_reclaim_page()
573  * @pool:	pool in which the allocation resides
583 void *zbud_map(struct zbud_pool *pool, unsigned long handle)  in zbud_map()  argument
590  * @pool:	pool in which the allocation resides
593 void zbud_unmap(struct zbud_pool *pool, unsigned long handle)  in zbud_unmap()  argument
598  * zbud_get_pool_size() - gets the zbud pool size in pages
599  * @pool:	pool whose size is being queried
601  * Returns: size in pages of the given pool.  The pool lock need not be
604 u64 zbud_get_pool_size(struct zbud_pool *pool)  in zbud_get_pool_size()  argument
606 	return pool->pages_nr;  in zbud_get_pool_size()