62  * freelists maintained in each pool. NCHUNKS_ORDER of 6 means that the
66  * 63 freelists per pool.
78  * struct zbud_pool - stores metadata for each zbud pool
79  * @lock:	protects all pool fields and first|last_chunk fields of any
80  *		zbud page in the pool
86  * @pages_nr:	number of zbud pages in the pool.
88  * This structure is allocated at pool creation time and maintains metadata
89  * pertaining to a particular zbud pool.
107  * @buddy:	links the zbud page into the unbuddied/buddied lists in the pool
153  * Pool lock should be held as this function accesses first|last_chunks
194  * zbud_create_pool() - create a new zbud pool
195  * @gfp:	gfp flags when allocating the zbud pool structure
197  * Return: pointer to the new zbud pool or NULL if the metadata allocation
202 	struct zbud_pool *pool;  in zbud_create_pool()  local
205 	pool = kzalloc(sizeof(struct zbud_pool), gfp);  in zbud_create_pool()
206 	if (!pool)  in zbud_create_pool()
208 	spin_lock_init(&pool->lock);  in zbud_create_pool()
210 		INIT_LIST_HEAD(&pool->unbuddied[i]);  in zbud_create_pool()
211 	INIT_LIST_HEAD(&pool->buddied);  in zbud_create_pool()
212 	pool->pages_nr = 0;  in zbud_create_pool()
213 	return pool;  in zbud_create_pool()
217  * zbud_destroy_pool() - destroys an existing zbud pool
218  * @pool:	the zbud pool to be destroyed
220  * The pool should be emptied before this function is called.
222 static void zbud_destroy_pool(struct zbud_pool *pool)  in zbud_destroy_pool()  argument
224 	kfree(pool);  in zbud_destroy_pool()
229  * @pool:	zbud pool from which to allocate
231  * @gfp:	gfp flags used if the pool needs to grow
234  * This function will attempt to find a free region in the pool large enough to
237  * allocated and added to the pool to satisfy the request.
240  * as zbud pool pages.
243  * gfp arguments are invalid or -ENOMEM if the pool was unable to allocate
246 static int zbud_alloc(struct zbud_pool *pool, size_t size, gfp_t gfp,  in zbud_alloc()  argument
259 	spin_lock(&pool->lock);  in zbud_alloc()
263 		if (!list_empty(&pool->unbuddied[i])) {  in zbud_alloc()
264 			zhdr = list_first_entry(&pool->unbuddied[i],  in zbud_alloc()
276 	spin_unlock(&pool->lock);  in zbud_alloc()
280 	spin_lock(&pool->lock);  in zbud_alloc()
281 	pool->pages_nr++;  in zbud_alloc()
294 		list_add(&zhdr->buddy, &pool->unbuddied[freechunks]);  in zbud_alloc()
297 		list_add(&zhdr->buddy, &pool->buddied);  in zbud_alloc()
301 	spin_unlock(&pool->lock);  in zbud_alloc()
308  * @pool:	pool in which the allocation resided
311 static void zbud_free(struct zbud_pool *pool, unsigned long handle)  in zbud_free()  argument
316 	spin_lock(&pool->lock);  in zbud_free()
331 		pool->pages_nr--;  in zbud_free()
335 		list_add(&zhdr->buddy, &pool->unbuddied[freechunks]);  in zbud_free()
338 	spin_unlock(&pool->lock);  in zbud_free()
343  * @pool:	pool in which the allocation resides
353 static void *zbud_map(struct zbud_pool *pool, unsigned long handle)  in zbud_map()  argument
360  * @pool:	pool in which the allocation resides
363 static void zbud_unmap(struct zbud_pool *pool, unsigned long handle)  in zbud_unmap()  argument
368  * zbud_get_pool_size() - gets the zbud pool size in pages
369  * @pool:	pool whose size is being queried
371  * Returns: size in pages of the given pool.  The pool lock need not be
374 static u64 zbud_get_pool_size(struct zbud_pool *pool)  in zbud_get_pool_size()  argument
376 	return pool->pages_nr;  in zbud_get_pool_size()
388 static void zbud_zpool_destroy(void *pool)  in zbud_zpool_destroy()  argument
390 	zbud_destroy_pool(pool);  in zbud_zpool_destroy()
393 static int zbud_zpool_malloc(void *pool, size_t size, gfp_t gfp,  in zbud_zpool_malloc()  argument
396 	return zbud_alloc(pool, size, gfp, handle);  in zbud_zpool_malloc()
398 static void zbud_zpool_free(void *pool, unsigned long handle)  in zbud_zpool_free()  argument
400 	zbud_free(pool, handle);  in zbud_zpool_free()
403 static void *zbud_zpool_map(void *pool, unsigned long handle,  in zbud_zpool_map()  argument
406 	return zbud_map(pool, handle);  in zbud_zpool_map()
408 static void zbud_zpool_unmap(void *pool, unsigned long handle)  in zbud_zpool_unmap()  argument
410 	zbud_unmap(pool, handle);  in zbud_zpool_unmap()
413 static u64 zbud_zpool_total_size(void *pool)  in zbud_zpool_total_size()  argument
415 	return zbud_get_pool_size(pool) * PAGE_SIZE;  in zbud_zpool_total_size()