1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2019, Intel Corporation. */
3
4 #include "ice_txrx_lib.h"
5 #include "ice_eswitch.h"
6 #include "ice_lib.h"
7
8 /**
9 * ice_release_rx_desc - Store the new tail and head values
10 * @rx_ring: ring to bump
11 * @val: new head index
12 */
ice_release_rx_desc(struct ice_rx_ring * rx_ring,u16 val)13 void ice_release_rx_desc(struct ice_rx_ring *rx_ring, u16 val)
14 {
15 u16 prev_ntu = rx_ring->next_to_use & ~0x7;
16
17 rx_ring->next_to_use = val;
18
19 /* update next to alloc since we have filled the ring */
20 rx_ring->next_to_alloc = val;
21
22 /* QRX_TAIL will be updated with any tail value, but hardware ignores
23 * the lower 3 bits. This makes it so we only bump tail on meaningful
24 * boundaries. Also, this allows us to bump tail on intervals of 8 up to
25 * the budget depending on the current traffic load.
26 */
27 val &= ~0x7;
28 if (prev_ntu != val) {
29 /* Force memory writes to complete before letting h/w
30 * know there are new descriptors to fetch. (Only
31 * applicable for weak-ordered memory model archs,
32 * such as IA-64).
33 */
34 wmb();
35 writel(val, rx_ring->tail);
36 }
37 }
38
39 /**
40 * ice_ptype_to_htype - get a hash type
41 * @ptype: the ptype value from the descriptor
42 *
43 * Returns appropriate hash type (such as PKT_HASH_TYPE_L2/L3/L4) to be used by
44 * skb_set_hash based on PTYPE as parsed by HW Rx pipeline and is part of
45 * Rx desc.
46 */
ice_ptype_to_htype(u16 ptype)47 static enum pkt_hash_types ice_ptype_to_htype(u16 ptype)
48 {
49 struct ice_rx_ptype_decoded decoded = ice_decode_rx_desc_ptype(ptype);
50
51 if (!decoded.known)
52 return PKT_HASH_TYPE_NONE;
53 if (decoded.payload_layer == ICE_RX_PTYPE_PAYLOAD_LAYER_PAY4)
54 return PKT_HASH_TYPE_L4;
55 if (decoded.payload_layer == ICE_RX_PTYPE_PAYLOAD_LAYER_PAY3)
56 return PKT_HASH_TYPE_L3;
57 if (decoded.outer_ip == ICE_RX_PTYPE_OUTER_L2)
58 return PKT_HASH_TYPE_L2;
59
60 return PKT_HASH_TYPE_NONE;
61 }
62
63 /**
64 * ice_rx_hash - set the hash value in the skb
65 * @rx_ring: descriptor ring
66 * @rx_desc: specific descriptor
67 * @skb: pointer to current skb
68 * @rx_ptype: the ptype value from the descriptor
69 */
70 static void
ice_rx_hash(struct ice_rx_ring * rx_ring,union ice_32b_rx_flex_desc * rx_desc,struct sk_buff * skb,u16 rx_ptype)71 ice_rx_hash(struct ice_rx_ring *rx_ring, union ice_32b_rx_flex_desc *rx_desc,
72 struct sk_buff *skb, u16 rx_ptype)
73 {
74 struct ice_32b_rx_flex_desc_nic *nic_mdid;
75 u32 hash;
76
77 if (!(rx_ring->netdev->features & NETIF_F_RXHASH))
78 return;
79
80 if (rx_desc->wb.rxdid != ICE_RXDID_FLEX_NIC)
81 return;
82
83 nic_mdid = (struct ice_32b_rx_flex_desc_nic *)rx_desc;
84 hash = le32_to_cpu(nic_mdid->rss_hash);
85 skb_set_hash(skb, hash, ice_ptype_to_htype(rx_ptype));
86 }
87
88 /**
89 * ice_rx_csum - Indicate in skb if checksum is good
90 * @ring: the ring we care about
91 * @skb: skb currently being received and modified
92 * @rx_desc: the receive descriptor
93 * @ptype: the packet type decoded by hardware
94 *
95 * skb->protocol must be set before this function is called
96 */
97 static void
ice_rx_csum(struct ice_rx_ring * ring,struct sk_buff * skb,union ice_32b_rx_flex_desc * rx_desc,u16 ptype)98 ice_rx_csum(struct ice_rx_ring *ring, struct sk_buff *skb,
99 union ice_32b_rx_flex_desc *rx_desc, u16 ptype)
100 {
101 struct ice_rx_ptype_decoded decoded;
102 u16 rx_status0, rx_status1;
103 bool ipv4, ipv6;
104
105 rx_status0 = le16_to_cpu(rx_desc->wb.status_error0);
106 rx_status1 = le16_to_cpu(rx_desc->wb.status_error1);
107
108 decoded = ice_decode_rx_desc_ptype(ptype);
109
110 /* Start with CHECKSUM_NONE and by default csum_level = 0 */
111 skb->ip_summed = CHECKSUM_NONE;
112 skb_checksum_none_assert(skb);
113
114 /* check if Rx checksum is enabled */
115 if (!(ring->netdev->features & NETIF_F_RXCSUM))
116 return;
117
118 /* check if HW has decoded the packet and checksum */
119 if (!(rx_status0 & BIT(ICE_RX_FLEX_DESC_STATUS0_L3L4P_S)))
120 return;
121
122 if (!(decoded.known && decoded.outer_ip))
123 return;
124
125 ipv4 = (decoded.outer_ip == ICE_RX_PTYPE_OUTER_IP) &&
126 (decoded.outer_ip_ver == ICE_RX_PTYPE_OUTER_IPV4);
127 ipv6 = (decoded.outer_ip == ICE_RX_PTYPE_OUTER_IP) &&
128 (decoded.outer_ip_ver == ICE_RX_PTYPE_OUTER_IPV6);
129
130 if (ipv4 && (rx_status0 & (BIT(ICE_RX_FLEX_DESC_STATUS0_XSUM_IPE_S) |
131 BIT(ICE_RX_FLEX_DESC_STATUS0_XSUM_EIPE_S))))
132 goto checksum_fail;
133
134 if (ipv6 && (rx_status0 & (BIT(ICE_RX_FLEX_DESC_STATUS0_IPV6EXADD_S))))
135 goto checksum_fail;
136
137 /* check for L4 errors and handle packets that were not able to be
138 * checksummed due to arrival speed
139 */
140 if (rx_status0 & BIT(ICE_RX_FLEX_DESC_STATUS0_XSUM_L4E_S))
141 goto checksum_fail;
142
143 /* check for outer UDP checksum error in tunneled packets */
144 if ((rx_status1 & BIT(ICE_RX_FLEX_DESC_STATUS1_NAT_S)) &&
145 (rx_status0 & BIT(ICE_RX_FLEX_DESC_STATUS0_XSUM_EUDPE_S)))
146 goto checksum_fail;
147
148 /* If there is an outer header present that might contain a checksum
149 * we need to bump the checksum level by 1 to reflect the fact that
150 * we are indicating we validated the inner checksum.
151 */
152 if (decoded.tunnel_type >= ICE_RX_PTYPE_TUNNEL_IP_GRENAT)
153 skb->csum_level = 1;
154
155 /* Only report checksum unnecessary for TCP, UDP, or SCTP */
156 switch (decoded.inner_prot) {
157 case ICE_RX_PTYPE_INNER_PROT_TCP:
158 case ICE_RX_PTYPE_INNER_PROT_UDP:
159 case ICE_RX_PTYPE_INNER_PROT_SCTP:
160 skb->ip_summed = CHECKSUM_UNNECESSARY;
161 break;
162 default:
163 break;
164 }
165 return;
166
167 checksum_fail:
168 ring->vsi->back->hw_csum_rx_error++;
169 }
170
171 /**
172 * ice_process_skb_fields - Populate skb header fields from Rx descriptor
173 * @rx_ring: Rx descriptor ring packet is being transacted on
174 * @rx_desc: pointer to the EOP Rx descriptor
175 * @skb: pointer to current skb being populated
176 * @ptype: the packet type decoded by hardware
177 *
178 * This function checks the ring, descriptor, and packet information in
179 * order to populate the hash, checksum, VLAN, protocol, and
180 * other fields within the skb.
181 */
182 void
ice_process_skb_fields(struct ice_rx_ring * rx_ring,union ice_32b_rx_flex_desc * rx_desc,struct sk_buff * skb,u16 ptype)183 ice_process_skb_fields(struct ice_rx_ring *rx_ring,
184 union ice_32b_rx_flex_desc *rx_desc,
185 struct sk_buff *skb, u16 ptype)
186 {
187 ice_rx_hash(rx_ring, rx_desc, skb, ptype);
188
189 /* modifies the skb - consumes the enet header */
190 skb->protocol = eth_type_trans(skb, ice_eswitch_get_target_netdev
191 (rx_ring, rx_desc));
192
193 ice_rx_csum(rx_ring, skb, rx_desc, ptype);
194
195 if (rx_ring->ptp_rx)
196 ice_ptp_rx_hwtstamp(rx_ring, rx_desc, skb);
197 }
198
199 /**
200 * ice_receive_skb - Send a completed packet up the stack
201 * @rx_ring: Rx ring in play
202 * @skb: packet to send up
203 * @vlan_tag: VLAN tag for packet
204 *
205 * This function sends the completed packet (via. skb) up the stack using
206 * gro receive functions (with/without VLAN tag)
207 */
208 void
ice_receive_skb(struct ice_rx_ring * rx_ring,struct sk_buff * skb,u16 vlan_tag)209 ice_receive_skb(struct ice_rx_ring *rx_ring, struct sk_buff *skb, u16 vlan_tag)
210 {
211 if ((rx_ring->netdev->features & NETIF_F_HW_VLAN_CTAG_RX) &&
212 (vlan_tag & VLAN_VID_MASK))
213 __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), vlan_tag);
214 napi_gro_receive(&rx_ring->q_vector->napi, skb);
215 }
216
217 /**
218 * ice_clean_xdp_irq - Reclaim resources after transmit completes on XDP ring
219 * @xdp_ring: XDP ring to clean
220 */
ice_clean_xdp_irq(struct ice_tx_ring * xdp_ring)221 static void ice_clean_xdp_irq(struct ice_tx_ring *xdp_ring)
222 {
223 unsigned int total_bytes = 0, total_pkts = 0;
224 u16 ntc = xdp_ring->next_to_clean;
225 struct ice_tx_desc *next_dd_desc;
226 u16 next_dd = xdp_ring->next_dd;
227 struct ice_tx_buf *tx_buf;
228 int i;
229
230 next_dd_desc = ICE_TX_DESC(xdp_ring, next_dd);
231 if (!(next_dd_desc->cmd_type_offset_bsz &
232 cpu_to_le64(ICE_TX_DESC_DTYPE_DESC_DONE)))
233 return;
234
235 for (i = 0; i < ICE_TX_THRESH; i++) {
236 tx_buf = &xdp_ring->tx_buf[ntc];
237
238 total_bytes += tx_buf->bytecount;
239 /* normally tx_buf->gso_segs was taken but at this point
240 * it's always 1 for us
241 */
242 total_pkts++;
243
244 page_frag_free(tx_buf->raw_buf);
245 dma_unmap_single(xdp_ring->dev, dma_unmap_addr(tx_buf, dma),
246 dma_unmap_len(tx_buf, len), DMA_TO_DEVICE);
247 dma_unmap_len_set(tx_buf, len, 0);
248 tx_buf->raw_buf = NULL;
249
250 ntc++;
251 if (ntc >= xdp_ring->count)
252 ntc = 0;
253 }
254
255 next_dd_desc->cmd_type_offset_bsz = 0;
256 xdp_ring->next_dd = xdp_ring->next_dd + ICE_TX_THRESH;
257 if (xdp_ring->next_dd > xdp_ring->count)
258 xdp_ring->next_dd = ICE_TX_THRESH - 1;
259 xdp_ring->next_to_clean = ntc;
260 ice_update_tx_ring_stats(xdp_ring, total_pkts, total_bytes);
261 }
262
263 /**
264 * ice_xmit_xdp_ring - submit single packet to XDP ring for transmission
265 * @data: packet data pointer
266 * @size: packet data size
267 * @xdp_ring: XDP ring for transmission
268 */
ice_xmit_xdp_ring(void * data,u16 size,struct ice_tx_ring * xdp_ring)269 int ice_xmit_xdp_ring(void *data, u16 size, struct ice_tx_ring *xdp_ring)
270 {
271 u16 i = xdp_ring->next_to_use;
272 struct ice_tx_desc *tx_desc;
273 struct ice_tx_buf *tx_buf;
274 dma_addr_t dma;
275
276 if (ICE_DESC_UNUSED(xdp_ring) < ICE_TX_THRESH)
277 ice_clean_xdp_irq(xdp_ring);
278
279 if (!unlikely(ICE_DESC_UNUSED(xdp_ring))) {
280 xdp_ring->tx_stats.tx_busy++;
281 return ICE_XDP_CONSUMED;
282 }
283
284 dma = dma_map_single(xdp_ring->dev, data, size, DMA_TO_DEVICE);
285 if (dma_mapping_error(xdp_ring->dev, dma))
286 return ICE_XDP_CONSUMED;
287
288 tx_buf = &xdp_ring->tx_buf[i];
289 tx_buf->bytecount = size;
290 tx_buf->gso_segs = 1;
291 tx_buf->raw_buf = data;
292
293 /* record length, and DMA address */
294 dma_unmap_len_set(tx_buf, len, size);
295 dma_unmap_addr_set(tx_buf, dma, dma);
296
297 tx_desc = ICE_TX_DESC(xdp_ring, i);
298 tx_desc->buf_addr = cpu_to_le64(dma);
299 tx_desc->cmd_type_offset_bsz = ice_build_ctob(ICE_TX_DESC_CMD_EOP, 0,
300 size, 0);
301
302 i++;
303 if (i == xdp_ring->count) {
304 i = 0;
305 tx_desc = ICE_TX_DESC(xdp_ring, xdp_ring->next_rs);
306 tx_desc->cmd_type_offset_bsz |=
307 cpu_to_le64(ICE_TX_DESC_CMD_RS << ICE_TXD_QW1_CMD_S);
308 xdp_ring->next_rs = ICE_TX_THRESH - 1;
309 }
310 xdp_ring->next_to_use = i;
311
312 if (i > xdp_ring->next_rs) {
313 tx_desc = ICE_TX_DESC(xdp_ring, xdp_ring->next_rs);
314 tx_desc->cmd_type_offset_bsz |=
315 cpu_to_le64(ICE_TX_DESC_CMD_RS << ICE_TXD_QW1_CMD_S);
316 xdp_ring->next_rs += ICE_TX_THRESH;
317 }
318
319 return ICE_XDP_TX;
320 }
321
322 /**
323 * ice_xmit_xdp_buff - convert an XDP buffer to an XDP frame and send it
324 * @xdp: XDP buffer
325 * @xdp_ring: XDP Tx ring
326 *
327 * Returns negative on failure, 0 on success.
328 */
ice_xmit_xdp_buff(struct xdp_buff * xdp,struct ice_tx_ring * xdp_ring)329 int ice_xmit_xdp_buff(struct xdp_buff *xdp, struct ice_tx_ring *xdp_ring)
330 {
331 struct xdp_frame *xdpf = xdp_convert_buff_to_frame(xdp);
332
333 if (unlikely(!xdpf))
334 return ICE_XDP_CONSUMED;
335
336 return ice_xmit_xdp_ring(xdpf->data, xdpf->len, xdp_ring);
337 }
338
339 /**
340 * ice_finalize_xdp_rx - Bump XDP Tx tail and/or flush redirect map
341 * @xdp_ring: XDP ring
342 * @xdp_res: Result of the receive batch
343 *
344 * This function bumps XDP Tx tail and/or flush redirect map, and
345 * should be called when a batch of packets has been processed in the
346 * napi loop.
347 */
ice_finalize_xdp_rx(struct ice_tx_ring * xdp_ring,unsigned int xdp_res)348 void ice_finalize_xdp_rx(struct ice_tx_ring *xdp_ring, unsigned int xdp_res)
349 {
350 if (xdp_res & ICE_XDP_REDIR)
351 xdp_do_flush_map();
352
353 if (xdp_res & ICE_XDP_TX) {
354 if (static_branch_unlikely(&ice_xdp_locking_key))
355 spin_lock(&xdp_ring->tx_lock);
356 ice_xdp_ring_update_tail(xdp_ring);
357 if (static_branch_unlikely(&ice_xdp_locking_key))
358 spin_unlock(&xdp_ring->tx_lock);
359 }
360 }
361