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 */
ice_release_rx_desc(struct ice_ring * rx_ring,u16 val)11 void 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 */
ice_ptype_to_htype(u8 __always_unused ptype)43 static 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 */
55 static void
ice_rx_hash(struct ice_ring * rx_ring,union ice_32b_rx_flex_desc * rx_desc,struct sk_buff * skb,u8 rx_ptype)56 ice_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 */
82 static void
ice_rx_csum(struct ice_ring * ring,struct sk_buff * skb,union ice_32b_rx_flex_desc * rx_desc,u8 ptype)83 ice_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 break;
147 default:
148 break;
149 }
150 return;
151
152 checksum_fail:
153 ring->vsi->back->hw_csum_rx_error++;
154 }
155
156 /**
157 * ice_process_skb_fields - Populate skb header fields from Rx descriptor
158 * @rx_ring: Rx descriptor ring packet is being transacted on
159 * @rx_desc: pointer to the EOP Rx descriptor
160 * @skb: pointer to current skb being populated
161 * @ptype: the packet type decoded by hardware
162 *
163 * This function checks the ring, descriptor, and packet information in
164 * order to populate the hash, checksum, VLAN, protocol, and
165 * other fields within the skb.
166 */
167 void
ice_process_skb_fields(struct ice_ring * rx_ring,union ice_32b_rx_flex_desc * rx_desc,struct sk_buff * skb,u8 ptype)168 ice_process_skb_fields(struct ice_ring *rx_ring,
169 union ice_32b_rx_flex_desc *rx_desc,
170 struct sk_buff *skb, u8 ptype)
171 {
172 ice_rx_hash(rx_ring, rx_desc, skb, ptype);
173
174 /* modifies the skb - consumes the enet header */
175 skb->protocol = eth_type_trans(skb, rx_ring->netdev);
176
177 ice_rx_csum(rx_ring, skb, rx_desc, ptype);
178 }
179
180 /**
181 * ice_receive_skb - Send a completed packet up the stack
182 * @rx_ring: Rx ring in play
183 * @skb: packet to send up
184 * @vlan_tag: VLAN tag for packet
185 *
186 * This function sends the completed packet (via. skb) up the stack using
187 * gro receive functions (with/without VLAN tag)
188 */
189 void
ice_receive_skb(struct ice_ring * rx_ring,struct sk_buff * skb,u16 vlan_tag)190 ice_receive_skb(struct ice_ring *rx_ring, struct sk_buff *skb, u16 vlan_tag)
191 {
192 if ((rx_ring->netdev->features & NETIF_F_HW_VLAN_CTAG_RX) &&
193 (vlan_tag & VLAN_VID_MASK))
194 __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), vlan_tag);
195 napi_gro_receive(&rx_ring->q_vector->napi, skb);
196 }
197
198 /**
199 * ice_xmit_xdp_ring - submit single packet to XDP ring for transmission
200 * @data: packet data pointer
201 * @size: packet data size
202 * @xdp_ring: XDP ring for transmission
203 */
ice_xmit_xdp_ring(void * data,u16 size,struct ice_ring * xdp_ring)204 int ice_xmit_xdp_ring(void *data, u16 size, struct ice_ring *xdp_ring)
205 {
206 u16 i = xdp_ring->next_to_use;
207 struct ice_tx_desc *tx_desc;
208 struct ice_tx_buf *tx_buf;
209 dma_addr_t dma;
210
211 if (!unlikely(ICE_DESC_UNUSED(xdp_ring))) {
212 xdp_ring->tx_stats.tx_busy++;
213 return ICE_XDP_CONSUMED;
214 }
215
216 dma = dma_map_single(xdp_ring->dev, data, size, DMA_TO_DEVICE);
217 if (dma_mapping_error(xdp_ring->dev, dma))
218 return ICE_XDP_CONSUMED;
219
220 tx_buf = &xdp_ring->tx_buf[i];
221 tx_buf->bytecount = size;
222 tx_buf->gso_segs = 1;
223 tx_buf->raw_buf = data;
224
225 /* record length, and DMA address */
226 dma_unmap_len_set(tx_buf, len, size);
227 dma_unmap_addr_set(tx_buf, dma, dma);
228
229 tx_desc = ICE_TX_DESC(xdp_ring, i);
230 tx_desc->buf_addr = cpu_to_le64(dma);
231 tx_desc->cmd_type_offset_bsz = ice_build_ctob(ICE_TXD_LAST_DESC_CMD, 0,
232 size, 0);
233
234 /* Make certain all of the status bits have been updated
235 * before next_to_watch is written.
236 */
237 smp_wmb();
238
239 i++;
240 if (i == xdp_ring->count)
241 i = 0;
242
243 tx_buf->next_to_watch = tx_desc;
244 xdp_ring->next_to_use = i;
245
246 return ICE_XDP_TX;
247 }
248
249 /**
250 * ice_xmit_xdp_buff - convert an XDP buffer to an XDP frame and send it
251 * @xdp: XDP buffer
252 * @xdp_ring: XDP Tx ring
253 *
254 * Returns negative on failure, 0 on success.
255 */
ice_xmit_xdp_buff(struct xdp_buff * xdp,struct ice_ring * xdp_ring)256 int ice_xmit_xdp_buff(struct xdp_buff *xdp, struct ice_ring *xdp_ring)
257 {
258 struct xdp_frame *xdpf = xdp_convert_buff_to_frame(xdp);
259
260 if (unlikely(!xdpf))
261 return ICE_XDP_CONSUMED;
262
263 return ice_xmit_xdp_ring(xdpf->data, xdpf->len, xdp_ring);
264 }
265
266 /**
267 * ice_finalize_xdp_rx - Bump XDP Tx tail and/or flush redirect map
268 * @rx_ring: Rx ring
269 * @xdp_res: Result of the receive batch
270 *
271 * This function bumps XDP Tx tail and/or flush redirect map, and
272 * should be called when a batch of packets has been processed in the
273 * napi loop.
274 */
ice_finalize_xdp_rx(struct ice_ring * rx_ring,unsigned int xdp_res)275 void ice_finalize_xdp_rx(struct ice_ring *rx_ring, unsigned int xdp_res)
276 {
277 if (xdp_res & ICE_XDP_REDIR)
278 xdp_do_flush_map();
279
280 if (xdp_res & ICE_XDP_TX) {
281 struct ice_ring *xdp_ring =
282 rx_ring->vsi->xdp_rings[rx_ring->q_index];
283
284 ice_xdp_ring_update_tail(xdp_ring);
285 }
286 }
287