[v1,1/1] ethdev: introduce pool sort capability

diff --git a/lib/ethdev/rte_ethdev.c b/lib/ethdev/rte_ethdev.c
index 1979dc0850..e21a651787 100644
--- a/lib/ethdev/rte_ethdev.c
+++ b/lib/ethdev/rte_ethdev.c
@@ -1634,6 +1634,54 @@  rte_eth_dev_is_removed(uint16_t port_id)
 	return ret;
 }
 
+static int
+rte_eth_rx_queue_check_sort(const struct rte_eth_rxseg_sort *rx_seg,
+			     uint16_t n_seg, uint32_t *mbp_buf_size,
+			     const struct rte_eth_dev_info *dev_info)
+{
+	const struct rte_eth_rxseg_capa *seg_capa = &dev_info->rx_seg_capa;
+	uint16_t seg_idx;
+
+	if (!seg_capa->multi_pools || n_seg > seg_capa->max_npool) {
+		RTE_ETHDEV_LOG(ERR,
+			       "Invalid capabilities, multi_pools:%d differnt length segments %u exceed supported %u\n",
+			       seg_capa->multi_pools, n_seg, seg_capa->max_nseg);
+		return -EINVAL;
+	}
+
+	for (seg_idx = 0; seg_idx < n_seg; seg_idx++) {
+		struct rte_mempool *mpl = rx_seg[seg_idx].mp;
+		uint32_t length = rx_seg[seg_idx].length;
+
+		if (mpl == NULL) {
+			RTE_ETHDEV_LOG(ERR, "null mempool pointer\n");
+			return -EINVAL;
+		}
+
+		if (mpl->private_data_size <
+			sizeof(struct rte_pktmbuf_pool_private)) {
+			RTE_ETHDEV_LOG(ERR,
+				       "%s private_data_size %u < %u\n",
+				       mpl->name, mpl->private_data_size,
+				       (unsigned int)sizeof
+					(struct rte_pktmbuf_pool_private));
+			return -ENOSPC;
+		}
+
+		*mbp_buf_size = rte_pktmbuf_data_room_size(mpl);
+		length = length != 0 ? length : (*mbp_buf_size - RTE_PKTMBUF_HEADROOM);
+		if (*mbp_buf_size < length + RTE_PKTMBUF_HEADROOM) {
+			RTE_ETHDEV_LOG(ERR,
+				       "%s mbuf_data_room_size %u < %u))\n",
+				       mpl->name, *mbp_buf_size,
+				       length);
+			return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
 static int
 rte_eth_rx_queue_check_split(const struct rte_eth_rxseg_split *rx_seg,
 			     uint16_t n_seg, uint32_t *mbp_buf_size,
@@ -1693,7 +1741,11 @@  rte_eth_rx_queue_check_split(const struct rte_eth_rxseg_split *rx_seg,
 		}
 		offset += seg_idx != 0 ? 0 : RTE_PKTMBUF_HEADROOM;
 		*mbp_buf_size = rte_pktmbuf_data_room_size(mpl);
-		length = length != 0 ? length : *mbp_buf_size;
+		/* On segment length == 0, update segment's length with
+		 * the pool's length - headeroom space, to make sure enough
+		 * space is accomidate for header.
+		 **/
+		length = length != 0 ? length : (*mbp_buf_size - RTE_PKTMBUF_HEADROOM);
 		if (*mbp_buf_size < length + offset) {
 			RTE_ETHDEV_LOG(ERR,
 				       "%s mbuf_data_room_size %u < %u (segment length=%u + segment offset=%u)\n",
@@ -1765,6 +1817,7 @@  rte_eth_rx_queue_setup(uint16_t port_id, uint16_t rx_queue_id,
 		}
 	} else {
 		const struct rte_eth_rxseg_split *rx_seg;
+		const struct rte_eth_rxseg_sort *rx_sort;
 		uint16_t n_seg;
 
 		/* Extended multi-segment configuration check. */
@@ -1774,13 +1827,31 @@  rte_eth_rx_queue_setup(uint16_t port_id, uint16_t rx_queue_id,
 			return -EINVAL;
 		}
 
-		rx_seg = (const struct rte_eth_rxseg_split *)rx_conf->rx_seg;
 		n_seg = rx_conf->rx_nseg;
 
 		if (rx_conf->offloads & RTE_ETH_RX_OFFLOAD_BUFFER_SPLIT) {
-			ret = rte_eth_rx_queue_check_split(rx_seg, n_seg,
-							   &mbp_buf_size,
-							   &dev_info);
+			ret = -1; /* To make sure at least one of below conditions becomes true */
+
+			/* Check both NIX and application supports buffer-split capability */
+			if (dev_info.rx_seg_capa.mode_flag == RTE_ETH_RXSEG_MODE_SPLIT &&
+			    rx_conf->rx_seg->mode_flag == RTE_ETH_RXSEG_MODE_SPLIT) {
+				rx_seg = (const struct rte_eth_rxseg_split *)
+					 &(rx_conf->rx_seg->split);
+				ret = rte_eth_rx_queue_check_split(rx_seg, n_seg,
+								   &mbp_buf_size,
+								   &dev_info);
+			}
+
+			/* Check both NIX and application supports pool-sort capability */
+			if (dev_info.rx_seg_capa.mode_flag == RTE_ETH_RXSEG_MODE_SORT &&
+			    rx_conf->rx_seg->mode_flag == RTE_ETH_RXSEG_MODE_SORT) {
+				rx_sort = (const struct rte_eth_rxseg_sort *)
+					  &(rx_conf->rx_seg->sort);
+				ret = rte_eth_rx_queue_check_sort(rx_sort, n_seg,
+								  &mbp_buf_size,
+								  &dev_info);
+			}
+
 			if (ret != 0)
 				return ret;
 		} else {
diff --git a/lib/ethdev/rte_ethdev.h b/lib/ethdev/rte_ethdev.h
index de9e970d4d..9ff8ba8085 100644
--- a/lib/ethdev/rte_ethdev.h
+++ b/lib/ethdev/rte_ethdev.h
@@ -1204,16 +1204,53 @@  struct rte_eth_rxseg_split {
 	uint32_t reserved; /**< Reserved field. */
 };
 
+/**
+ * The pool sort capability allows PMD to choose a memory pool based on the
+ * packet's length. So, basically, PMD programs HW for receiving packets from
+ * different pools, based on the packet's length.
+ *
+ * This is often useful for saving the memory where the application can create
+ * a different pool to steer the specific size of the packet, thus enabling
+ * effective use of memory.
+ */
+struct rte_eth_rxseg_sort {
+	struct rte_mempool *mp; /**< Memory pool to allocate packets from. */
+	uint16_t length; /**< Packet data length. */
+	uint32_t reserved; /**< Reserved field. */
+};
+
+enum rte_eth_rxseg_mode {
+	/**
+	 * Buffer split mode: PMD split the received packets into multiple segments.
+	 * @see struct rte_eth_rxseg_split
+	 */
+	RTE_ETH_RXSEG_MODE_SPLIT = RTE_BIT64(0),
+	/**
+	 * Pool sort mode: PMD to chooses a memory pool based on the packet's length.
+	 * @see struct rte_eth_rxseg_sort
+	 */
+	RTE_ETH_RXSEG_MODE_SORT  = RTE_BIT64(1),
+};
+
 /**
  * @warning
  * @b EXPERIMENTAL: this structure may change without prior notice.
  *
  * A common structure used to describe Rx packet segment properties.
  */
-union rte_eth_rxseg {
+struct rte_eth_rxseg {
+
+	/**
+	 * PMD may support more than one rxseg mode. This allows application
+	 * to chose which mode to enable.
+	 */
+	enum rte_eth_rxseg_mode mode_flag;
+
 	/* The settings for buffer split offload. */
 	struct rte_eth_rxseg_split split;
-	/* The other features settings should be added here. */
+
+	/*The settings for packet sort offload. */
+	struct rte_eth_rxseg_sort sort;
 };
 
 /**
@@ -1246,7 +1283,7 @@  struct rte_eth_rxconf {
 	 * The supported capabilities of receiving segmentation is reported
 	 * in rte_eth_dev_info.rx_seg_capa field.
 	 */
-	union rte_eth_rxseg *rx_seg;
+	struct rte_eth_rxseg *rx_seg;
 
 	uint64_t reserved_64s[2]; /**< Reserved for future fields */
 	void *reserved_ptrs[2];   /**< Reserved for future fields */
@@ -1831,6 +1868,9 @@  struct rte_eth_rxseg_capa {
 	uint32_t offset_allowed:1; /**< Supports buffer offsets. */
 	uint32_t offset_align_log2:4; /**< Required offset alignment. */
 	uint16_t max_nseg; /**< Maximum amount of segments to split. */
+	/* < Maximum amount of pools that PMD can sort based on packet/segment lengths */
+	uint16_t max_npool;
+	enum rte_eth_rxseg_mode mode_flag; /**< supported rxseg  modes */
 	uint16_t reserved; /**< Reserved field. */
 };