Function alloc_ring

dpdk/drivers/net/cxgbe/sge.c:1385–1429

* alloc_ring - allocate resources for an SGE descriptor ring * @dev: the port associated with the queue * @z_name: memzone's name * @queue_id: queue index * @socket_id: preferred socket id for memory allocations * @nelem: the number of descriptors * @elem_size: the size of each descriptor * @stat_size: extra space in HW ring for status information * @sw_size: the size of the SW state assoc

 * of the SW ring.
 */
static void *alloc_ring(struct rte_eth_dev *dev, const char *z_name,
			uint16_t queue_id, int socket_id, size_t nelem,
			size_t elem_size, size_t stat_size, size_t sw_size,
			dma_addr_t *phys, void *metadata)
{
	size_t len = CXGBE_MAX_RING_DESC_SIZE * elem_size + stat_size;
	char z_name_sw[RTE_MEMZONE_NAMESIZE];
	const struct rte_memzone *tz;
	void *s = NULL;

	snprintf(z_name_sw, sizeof(z_name_sw), "eth_p%d_q%d_%s_sw_ring",
		 dev->data->port_id, queue_id, z_name);

	dev_debug(adapter, "%s: nelem = %zu; elem_size = %zu; sw_size = %zu; "
		  "stat_size = %zu; queue_id = %u; socket_id = %d; z_name = %s;"
		  " z_name_sw = %s\n", __func__, nelem, elem_size, sw_size,
		  stat_size, queue_id, socket_id, z_name, z_name_sw);

	/*
	 * Allocate TX/RX ring hardware descriptors. A memzone large enough to
	 * handle the maximum ring size is allocated in order to allow for
	 * resizing in later calls to the queue setup function.
	 */
	tz = rte_eth_dma_zone_reserve(dev, z_name, queue_id, len, 4096,
				      socket_id);
	if (!tz)
		return NULL;

	memset(tz->addr, 0, len);
	if (sw_size) {
		s = rte_zmalloc_socket(z_name_sw, nelem * sw_size,
				       RTE_CACHE_LINE_SIZE, socket_id);

		if (!s) {
			dev_err(adapter, "%s: failed to get sw_ring memory\n",
				__func__);
			return NULL;
		}
	}
	if (metadata)
		*(void **)metadata = s;

	*phys = (uint64_t)tz->iova;
	return tz->addr;
}

#define CXGB4_MSG_AN ((void *)1)