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 a hash type to be used by skb_set_hash
 42 */
 43static enum pkt_hash_types ice_ptype_to_htype(u8 __always_unused ptype)
 44{
 45	return PKT_HASH_TYPE_NONE;
 46}
 47
 48/**
 49 * ice_rx_hash - set the hash value in the skb
 50 * @rx_ring: descriptor ring
 51 * @rx_desc: specific descriptor
 52 * @skb: pointer to current skb
 53 * @rx_ptype: the ptype value from the descriptor
 54 */
 55static void
 56ice_rx_hash(struct ice_ring *rx_ring, union ice_32b_rx_flex_desc *rx_desc,
 57	    struct sk_buff *skb, u8 rx_ptype)
 58{
 59	struct ice_32b_rx_flex_desc_nic *nic_mdid;
 60	u32 hash;
 61
 62	if (!(rx_ring->netdev->features & NETIF_F_RXHASH))
 63		return;
 64
 65	if (rx_desc->wb.rxdid != ICE_RXDID_FLEX_NIC)
 66		return;
 67
 68	nic_mdid = (struct ice_32b_rx_flex_desc_nic *)rx_desc;
 69	hash = le32_to_cpu(nic_mdid->rss_hash);
 70	skb_set_hash(skb, hash, ice_ptype_to_htype(rx_ptype));
 71}
 72
 73/**
 74 * ice_rx_csum - Indicate in skb if checksum is good
 75 * @ring: the ring we care about
 76 * @skb: skb currently being received and modified
 77 * @rx_desc: the receive descriptor
 78 * @ptype: the packet type decoded by hardware
 79 *
 80 * skb->protocol must be set before this function is called
 81 */
 82static void
 83ice_rx_csum(struct ice_ring *ring, struct sk_buff *skb,
 84	    union ice_32b_rx_flex_desc *rx_desc, u8 ptype)
 85{
 86	struct ice_rx_ptype_decoded decoded;
 87	u16 rx_status0, rx_status1;
 88	bool ipv4, ipv6;
 89
 90	rx_status0 = le16_to_cpu(rx_desc->wb.status_error0);
 91	rx_status1 = le16_to_cpu(rx_desc->wb.status_error1);
 92
 93	decoded = ice_decode_rx_desc_ptype(ptype);
 94
 95	/* Start with CHECKSUM_NONE and by default csum_level = 0 */
 96	skb->ip_summed = CHECKSUM_NONE;
 97	skb_checksum_none_assert(skb);
 98
 99	/* check if Rx checksum is enabled */
100	if (!(ring->netdev->features & NETIF_F_RXCSUM))
101		return;
102
103	/* check if HW has decoded the packet and checksum */
104	if (!(rx_status0 & BIT(ICE_RX_FLEX_DESC_STATUS0_L3L4P_S)))
105		return;
106
107	if (!(decoded.known && decoded.outer_ip))
108		return;
109
110	ipv4 = (decoded.outer_ip == ICE_RX_PTYPE_OUTER_IP) &&
111	       (decoded.outer_ip_ver == ICE_RX_PTYPE_OUTER_IPV4);
112	ipv6 = (decoded.outer_ip == ICE_RX_PTYPE_OUTER_IP) &&
113	       (decoded.outer_ip_ver == ICE_RX_PTYPE_OUTER_IPV6);
114
115	if (ipv4 && (rx_status0 & (BIT(ICE_RX_FLEX_DESC_STATUS0_XSUM_IPE_S) |
116				   BIT(ICE_RX_FLEX_DESC_STATUS0_XSUM_EIPE_S))))
117		goto checksum_fail;
118
119	if (ipv6 && (rx_status0 & (BIT(ICE_RX_FLEX_DESC_STATUS0_IPV6EXADD_S))))
120		goto checksum_fail;
121
122	/* check for L4 errors and handle packets that were not able to be
123	 * checksummed due to arrival speed
124	 */
125	if (rx_status0 & BIT(ICE_RX_FLEX_DESC_STATUS0_XSUM_L4E_S))
126		goto checksum_fail;
127
128	/* check for outer UDP checksum error in tunneled packets */
129	if ((rx_status1 & BIT(ICE_RX_FLEX_DESC_STATUS1_NAT_S)) &&
130	    (rx_status0 & BIT(ICE_RX_FLEX_DESC_STATUS0_XSUM_EUDPE_S)))
131		goto checksum_fail;
132
133	/* If there is an outer header present that might contain a checksum
134	 * we need to bump the checksum level by 1 to reflect the fact that
135	 * we are indicating we validated the inner checksum.
136	 */
137	if (decoded.tunnel_type >= ICE_RX_PTYPE_TUNNEL_IP_GRENAT)
138		skb->csum_level = 1;
139
140	/* Only report checksum unnecessary for TCP, UDP, or SCTP */
141	switch (decoded.inner_prot) {
142	case ICE_RX_PTYPE_INNER_PROT_TCP:
143	case ICE_RX_PTYPE_INNER_PROT_UDP:
144	case ICE_RX_PTYPE_INNER_PROT_SCTP:
145		skb->ip_summed = CHECKSUM_UNNECESSARY;
146	default:
147		break;
148	}
149	return;
150
151checksum_fail:
152	ring->vsi->back->hw_csum_rx_error++;
153}
154
155/**
156 * ice_process_skb_fields - Populate skb header fields from Rx descriptor
157 * @rx_ring: Rx descriptor ring packet is being transacted on
158 * @rx_desc: pointer to the EOP Rx descriptor
159 * @skb: pointer to current skb being populated
160 * @ptype: the packet type decoded by hardware
161 *
162 * This function checks the ring, descriptor, and packet information in
163 * order to populate the hash, checksum, VLAN, protocol, and
164 * other fields within the skb.
165 */
166void
167ice_process_skb_fields(struct ice_ring *rx_ring,
168		       union ice_32b_rx_flex_desc *rx_desc,
169		       struct sk_buff *skb, u8 ptype)
170{
171	ice_rx_hash(rx_ring, rx_desc, skb, ptype);
172
173	/* modifies the skb - consumes the enet header */
174	skb->protocol = eth_type_trans(skb, rx_ring->netdev);
175
176	ice_rx_csum(rx_ring, skb, rx_desc, ptype);
177}
178
179/**
180 * ice_receive_skb - Send a completed packet up the stack
181 * @rx_ring: Rx ring in play
182 * @skb: packet to send up
183 * @vlan_tag: VLAN tag for packet
184 *
185 * This function sends the completed packet (via. skb) up the stack using
186 * gro receive functions (with/without VLAN tag)
187 */
188void
189ice_receive_skb(struct ice_ring *rx_ring, struct sk_buff *skb, u16 vlan_tag)
190{
191	if ((rx_ring->netdev->features & NETIF_F_HW_VLAN_CTAG_RX) &&
192	    (vlan_tag & VLAN_VID_MASK))
193		__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), vlan_tag);
194	if (napi_gro_receive(&rx_ring->q_vector->napi, skb) == GRO_DROP) {
195		/* this is tracked separately to help us debug stack drops */
196		rx_ring->rx_stats.gro_dropped++;
197		netdev_dbg(rx_ring->netdev, "Receive Queue %d: Dropped packet from GRO\n",
198			   rx_ring->q_index);
199	}
200}
201
202/**
203 * ice_xmit_xdp_ring - submit single packet to XDP ring for transmission
204 * @data: packet data pointer
205 * @size: packet data size
206 * @xdp_ring: XDP ring for transmission
207 */
208int ice_xmit_xdp_ring(void *data, u16 size, struct ice_ring *xdp_ring)
209{
210	u16 i = xdp_ring->next_to_use;
211	struct ice_tx_desc *tx_desc;
212	struct ice_tx_buf *tx_buf;
213	dma_addr_t dma;
214
215	if (!unlikely(ICE_DESC_UNUSED(xdp_ring))) {
216		xdp_ring->tx_stats.tx_busy++;
217		return ICE_XDP_CONSUMED;
218	}
219
220	dma = dma_map_single(xdp_ring->dev, data, size, DMA_TO_DEVICE);
221	if (dma_mapping_error(xdp_ring->dev, dma))
222		return ICE_XDP_CONSUMED;
223
224	tx_buf = &xdp_ring->tx_buf[i];
225	tx_buf->bytecount = size;
226	tx_buf->gso_segs = 1;
227	tx_buf->raw_buf = data;
228
229	/* record length, and DMA address */
230	dma_unmap_len_set(tx_buf, len, size);
231	dma_unmap_addr_set(tx_buf, dma, dma);
232
233	tx_desc = ICE_TX_DESC(xdp_ring, i);
234	tx_desc->buf_addr = cpu_to_le64(dma);
235	tx_desc->cmd_type_offset_bsz = ice_build_ctob(ICE_TXD_LAST_DESC_CMD, 0,
236						      size, 0);
237
238	/* Make certain all of the status bits have been updated
239	 * before next_to_watch is written.
240	 */
241	smp_wmb();
242
243	i++;
244	if (i == xdp_ring->count)
245		i = 0;
246
247	tx_buf->next_to_watch = tx_desc;
248	xdp_ring->next_to_use = i;
249
250	return ICE_XDP_TX;
251}
252
253/**
254 * ice_xmit_xdp_buff - convert an XDP buffer to an XDP frame and send it
255 * @xdp: XDP buffer
256 * @xdp_ring: XDP Tx ring
257 *
258 * Returns negative on failure, 0 on success.
259 */
260int ice_xmit_xdp_buff(struct xdp_buff *xdp, struct ice_ring *xdp_ring)
261{
262	struct xdp_frame *xdpf = xdp_convert_buff_to_frame(xdp);
263
264	if (unlikely(!xdpf))
265		return ICE_XDP_CONSUMED;
266
267	return ice_xmit_xdp_ring(xdpf->data, xdpf->len, xdp_ring);
268}
269
270/**
271 * ice_finalize_xdp_rx - Bump XDP Tx tail and/or flush redirect map
272 * @rx_ring: Rx ring
273 * @xdp_res: Result of the receive batch
274 *
275 * This function bumps XDP Tx tail and/or flush redirect map, and
276 * should be called when a batch of packets has been processed in the
277 * napi loop.
278 */
279void ice_finalize_xdp_rx(struct ice_ring *rx_ring, unsigned int xdp_res)
280{
281	if (xdp_res & ICE_XDP_REDIR)
282		xdp_do_flush_map();
283
284	if (xdp_res & ICE_XDP_TX) {
285		struct ice_ring *xdp_ring =
286			rx_ring->vsi->xdp_rings[rx_ring->q_index];
287
288		ice_xdp_ring_update_tail(xdp_ring);
289	}
290}