1// SPDX-License-Identifier: GPL-2.0
  2/* Copyright (c) 2019, Intel Corporation. */
  3
  4#include "ice_txrx_lib.h"
  5
  6/**
  7 * ice_release_rx_desc - Store the new tail and head values
  8 * @rx_ring: ring to bump
  9 * @val: new head index
 10 */
 11void ice_release_rx_desc(struct ice_ring *rx_ring, u16 val)
 12{
 13	u16 prev_ntu = rx_ring->next_to_use & ~0x7;
 14
 15	rx_ring->next_to_use = val;
 16
 17	/* update next to alloc since we have filled the ring */
 18	rx_ring->next_to_alloc = val;
 19
 20	/* QRX_TAIL will be updated with any tail value, but hardware ignores
 21	 * the lower 3 bits. This makes it so we only bump tail on meaningful
 22	 * boundaries. Also, this allows us to bump tail on intervals of 8 up to
 23	 * the budget depending on the current traffic load.
 24	 */
 25	val &= ~0x7;
 26	if (prev_ntu != val) {
 27		/* Force memory writes to complete before letting h/w
 28		 * know there are new descriptors to fetch. (Only
 29		 * applicable for weak-ordered memory model archs,
 30		 * such as IA-64).
 31		 */
 32		wmb();
 33		writel(val, rx_ring->tail);
 34	}
 35}
 36
 37/**
 38 * ice_ptype_to_htype - get a hash type
 39 * @ptype: the ptype value from the descriptor
 40 *
 41 * Returns appropriate hash type (such as PKT_HASH_TYPE_L2/L3/L4) to be used by
 42 * skb_set_hash based on PTYPE as parsed by HW Rx pipeline and is part of
 43 * Rx desc.
 44 */
 45static enum pkt_hash_types ice_ptype_to_htype(u16 ptype)
 46{
 47	struct ice_rx_ptype_decoded decoded = ice_decode_rx_desc_ptype(ptype);
 48
 49	if (!decoded.known)
 50		return PKT_HASH_TYPE_NONE;
 51	if (decoded.payload_layer == ICE_RX_PTYPE_PAYLOAD_LAYER_PAY4)
 52		return PKT_HASH_TYPE_L4;
 53	if (decoded.payload_layer == ICE_RX_PTYPE_PAYLOAD_LAYER_PAY3)
 54		return PKT_HASH_TYPE_L3;
 55	if (decoded.outer_ip == ICE_RX_PTYPE_OUTER_L2)
 56		return PKT_HASH_TYPE_L2;
 57
 58	return PKT_HASH_TYPE_NONE;
 59}
 60
 61/**
 62 * ice_rx_hash - set the hash value in the skb
 63 * @rx_ring: descriptor ring
 64 * @rx_desc: specific descriptor
 65 * @skb: pointer to current skb
 66 * @rx_ptype: the ptype value from the descriptor
 67 */
 68static void
 69ice_rx_hash(struct ice_ring *rx_ring, union ice_32b_rx_flex_desc *rx_desc,
 70	    struct sk_buff *skb, u16 rx_ptype)
 71{
 72	struct ice_32b_rx_flex_desc_nic *nic_mdid;
 73	u32 hash;
 74
 75	if (!(rx_ring->netdev->features & NETIF_F_RXHASH))
 76		return;
 77
 78	if (rx_desc->wb.rxdid != ICE_RXDID_FLEX_NIC)
 79		return;
 80
 81	nic_mdid = (struct ice_32b_rx_flex_desc_nic *)rx_desc;
 82	hash = le32_to_cpu(nic_mdid->rss_hash);
 83	skb_set_hash(skb, hash, ice_ptype_to_htype(rx_ptype));
 84}
 85
 86/**
 87 * ice_rx_csum - Indicate in skb if checksum is good
 88 * @ring: the ring we care about
 89 * @skb: skb currently being received and modified
 90 * @rx_desc: the receive descriptor
 91 * @ptype: the packet type decoded by hardware
 92 *
 93 * skb->protocol must be set before this function is called
 94 */
 95static void
 96ice_rx_csum(struct ice_ring *ring, struct sk_buff *skb,
 97	    union ice_32b_rx_flex_desc *rx_desc, u16 ptype)
 98{
 99	struct ice_rx_ptype_decoded decoded;
100	u16 rx_status0, rx_status1;
101	bool ipv4, ipv6;
102
103	rx_status0 = le16_to_cpu(rx_desc->wb.status_error0);
104	rx_status1 = le16_to_cpu(rx_desc->wb.status_error1);
105
106	decoded = ice_decode_rx_desc_ptype(ptype);
107
108	/* Start with CHECKSUM_NONE and by default csum_level = 0 */
109	skb->ip_summed = CHECKSUM_NONE;
110	skb_checksum_none_assert(skb);
111
112	/* check if Rx checksum is enabled */
113	if (!(ring->netdev->features & NETIF_F_RXCSUM))
114		return;
115
116	/* check if HW has decoded the packet and checksum */
117	if (!(rx_status0 & BIT(ICE_RX_FLEX_DESC_STATUS0_L3L4P_S)))
118		return;
119
120	if (!(decoded.known && decoded.outer_ip))
121		return;
122
123	ipv4 = (decoded.outer_ip == ICE_RX_PTYPE_OUTER_IP) &&
124	       (decoded.outer_ip_ver == ICE_RX_PTYPE_OUTER_IPV4);
125	ipv6 = (decoded.outer_ip == ICE_RX_PTYPE_OUTER_IP) &&
126	       (decoded.outer_ip_ver == ICE_RX_PTYPE_OUTER_IPV6);
127
128	if (ipv4 && (rx_status0 & (BIT(ICE_RX_FLEX_DESC_STATUS0_XSUM_IPE_S) |
129				   BIT(ICE_RX_FLEX_DESC_STATUS0_XSUM_EIPE_S))))
130		goto checksum_fail;
131
132	if (ipv6 && (rx_status0 & (BIT(ICE_RX_FLEX_DESC_STATUS0_IPV6EXADD_S))))
133		goto checksum_fail;
134
135	/* check for L4 errors and handle packets that were not able to be
136	 * checksummed due to arrival speed
137	 */
138	if (rx_status0 & BIT(ICE_RX_FLEX_DESC_STATUS0_XSUM_L4E_S))
139		goto checksum_fail;
140
141	/* check for outer UDP checksum error in tunneled packets */
142	if ((rx_status1 & BIT(ICE_RX_FLEX_DESC_STATUS1_NAT_S)) &&
143	    (rx_status0 & BIT(ICE_RX_FLEX_DESC_STATUS0_XSUM_EUDPE_S)))
144		goto checksum_fail;
145
146	/* If there is an outer header present that might contain a checksum
147	 * we need to bump the checksum level by 1 to reflect the fact that
148	 * we are indicating we validated the inner checksum.
149	 */
150	if (decoded.tunnel_type >= ICE_RX_PTYPE_TUNNEL_IP_GRENAT)
151		skb->csum_level = 1;
152
153	/* Only report checksum unnecessary for TCP, UDP, or SCTP */
154	switch (decoded.inner_prot) {
155	case ICE_RX_PTYPE_INNER_PROT_TCP:
156	case ICE_RX_PTYPE_INNER_PROT_UDP:
157	case ICE_RX_PTYPE_INNER_PROT_SCTP:
158		skb->ip_summed = CHECKSUM_UNNECESSARY;
159		break;
160	default:
161		break;
162	}
163	return;
164
165checksum_fail:
166	ring->vsi->back->hw_csum_rx_error++;
167}
168
169/**
170 * ice_process_skb_fields - Populate skb header fields from Rx descriptor
171 * @rx_ring: Rx descriptor ring packet is being transacted on
172 * @rx_desc: pointer to the EOP Rx descriptor
173 * @skb: pointer to current skb being populated
174 * @ptype: the packet type decoded by hardware
175 *
176 * This function checks the ring, descriptor, and packet information in
177 * order to populate the hash, checksum, VLAN, protocol, and
178 * other fields within the skb.
179 */
180void
181ice_process_skb_fields(struct ice_ring *rx_ring,
182		       union ice_32b_rx_flex_desc *rx_desc,
183		       struct sk_buff *skb, u16 ptype)
184{
185	ice_rx_hash(rx_ring, rx_desc, skb, ptype);
186
187	/* modifies the skb - consumes the enet header */
188	skb->protocol = eth_type_trans(skb, rx_ring->netdev);
189
190	ice_rx_csum(rx_ring, skb, rx_desc, ptype);
191
192	if (rx_ring->ptp_rx)
193		ice_ptp_rx_hwtstamp(rx_ring, rx_desc, skb);
194}
195
196/**
197 * ice_receive_skb - Send a completed packet up the stack
198 * @rx_ring: Rx ring in play
199 * @skb: packet to send up
200 * @vlan_tag: VLAN tag for packet
201 *
202 * This function sends the completed packet (via. skb) up the stack using
203 * gro receive functions (with/without VLAN tag)
204 */
205void
206ice_receive_skb(struct ice_ring *rx_ring, struct sk_buff *skb, u16 vlan_tag)
207{
208	if ((rx_ring->netdev->features & NETIF_F_HW_VLAN_CTAG_RX) &&
209	    (vlan_tag & VLAN_VID_MASK))
210		__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), vlan_tag);
211	napi_gro_receive(&rx_ring->q_vector->napi, skb);
212}
213
214/**
215 * ice_xmit_xdp_ring - submit single packet to XDP ring for transmission
216 * @data: packet data pointer
217 * @size: packet data size
218 * @xdp_ring: XDP ring for transmission
219 */
220int ice_xmit_xdp_ring(void *data, u16 size, struct ice_ring *xdp_ring)
221{
222	u16 i = xdp_ring->next_to_use;
223	struct ice_tx_desc *tx_desc;
224	struct ice_tx_buf *tx_buf;
225	dma_addr_t dma;
226
227	if (!unlikely(ICE_DESC_UNUSED(xdp_ring))) {
228		xdp_ring->tx_stats.tx_busy++;
229		return ICE_XDP_CONSUMED;
230	}
231
232	dma = dma_map_single(xdp_ring->dev, data, size, DMA_TO_DEVICE);
233	if (dma_mapping_error(xdp_ring->dev, dma))
234		return ICE_XDP_CONSUMED;
235
236	tx_buf = &xdp_ring->tx_buf[i];
237	tx_buf->bytecount = size;
238	tx_buf->gso_segs = 1;
239	tx_buf->raw_buf = data;
240
241	/* record length, and DMA address */
242	dma_unmap_len_set(tx_buf, len, size);
243	dma_unmap_addr_set(tx_buf, dma, dma);
244
245	tx_desc = ICE_TX_DESC(xdp_ring, i);
246	tx_desc->buf_addr = cpu_to_le64(dma);
247	tx_desc->cmd_type_offset_bsz = ice_build_ctob(ICE_TXD_LAST_DESC_CMD, 0,
248						      size, 0);
249
250	/* Make certain all of the status bits have been updated
251	 * before next_to_watch is written.
252	 */
253	smp_wmb();
254
255	i++;
256	if (i == xdp_ring->count)
257		i = 0;
258
259	tx_buf->next_to_watch = tx_desc;
260	xdp_ring->next_to_use = i;
261
262	return ICE_XDP_TX;
263}
264
265/**
266 * ice_xmit_xdp_buff - convert an XDP buffer to an XDP frame and send it
267 * @xdp: XDP buffer
268 * @xdp_ring: XDP Tx ring
269 *
270 * Returns negative on failure, 0 on success.
271 */
272int ice_xmit_xdp_buff(struct xdp_buff *xdp, struct ice_ring *xdp_ring)
273{
274	struct xdp_frame *xdpf = xdp_convert_buff_to_frame(xdp);
275
276	if (unlikely(!xdpf))
277		return ICE_XDP_CONSUMED;
278
279	return ice_xmit_xdp_ring(xdpf->data, xdpf->len, xdp_ring);
280}
281
282/**
283 * ice_finalize_xdp_rx - Bump XDP Tx tail and/or flush redirect map
284 * @rx_ring: Rx ring
285 * @xdp_res: Result of the receive batch
286 *
287 * This function bumps XDP Tx tail and/or flush redirect map, and
288 * should be called when a batch of packets has been processed in the
289 * napi loop.
290 */
291void ice_finalize_xdp_rx(struct ice_ring *rx_ring, unsigned int xdp_res)
292{
293	if (xdp_res & ICE_XDP_REDIR)
294		xdp_do_flush_map();
295
296	if (xdp_res & ICE_XDP_TX) {
297		struct ice_ring *xdp_ring =
298			rx_ring->vsi->xdp_rings[rx_ring->q_index];
299
300		ice_xdp_ring_update_tail(xdp_ring);
301	}
302}