1 // SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2 /* Copyright (C) 2018 Netronome Systems, Inc */
3 /* Copyright (C) 2021 Corigine, Inc */
4
5 #include <linux/bpf_trace.h>
6 #include <linux/netdevice.h>
7
8 #include "../nfp_app.h"
9 #include "../nfp_net.h"
10 #include "../nfp_net_dp.h"
11 #include "../nfp_net_xsk.h"
12 #include "nfd3.h"
13
14 static bool
nfp_nfd3_xsk_tx_xdp(const struct nfp_net_dp * dp,struct nfp_net_r_vector * r_vec,struct nfp_net_rx_ring * rx_ring,struct nfp_net_tx_ring * tx_ring,struct nfp_net_xsk_rx_buf * xrxbuf,unsigned int pkt_len,int pkt_off)15 nfp_nfd3_xsk_tx_xdp(const struct nfp_net_dp *dp, struct nfp_net_r_vector *r_vec,
16 struct nfp_net_rx_ring *rx_ring,
17 struct nfp_net_tx_ring *tx_ring,
18 struct nfp_net_xsk_rx_buf *xrxbuf, unsigned int pkt_len,
19 int pkt_off)
20 {
21 struct xsk_buff_pool *pool = r_vec->xsk_pool;
22 struct nfp_nfd3_tx_buf *txbuf;
23 struct nfp_nfd3_tx_desc *txd;
24 unsigned int wr_idx;
25
26 if (nfp_net_tx_space(tx_ring) < 1)
27 return false;
28
29 xsk_buff_raw_dma_sync_for_device(pool, xrxbuf->dma_addr + pkt_off,
30 pkt_len);
31
32 wr_idx = D_IDX(tx_ring, tx_ring->wr_p);
33
34 txbuf = &tx_ring->txbufs[wr_idx];
35 txbuf->xdp = xrxbuf->xdp;
36 txbuf->real_len = pkt_len;
37 txbuf->is_xsk_tx = true;
38
39 /* Build TX descriptor */
40 txd = &tx_ring->txds[wr_idx];
41 txd->offset_eop = NFD3_DESC_TX_EOP;
42 txd->dma_len = cpu_to_le16(pkt_len);
43 nfp_desc_set_dma_addr(txd, xrxbuf->dma_addr + pkt_off);
44 txd->data_len = cpu_to_le16(pkt_len);
45
46 txd->flags = 0;
47 txd->mss = 0;
48 txd->lso_hdrlen = 0;
49
50 tx_ring->wr_ptr_add++;
51 tx_ring->wr_p++;
52
53 return true;
54 }
55
nfp_nfd3_xsk_rx_skb(struct nfp_net_rx_ring * rx_ring,const struct nfp_net_rx_desc * rxd,struct nfp_net_xsk_rx_buf * xrxbuf,const struct nfp_meta_parsed * meta,unsigned int pkt_len,bool meta_xdp,unsigned int * skbs_polled)56 static void nfp_nfd3_xsk_rx_skb(struct nfp_net_rx_ring *rx_ring,
57 const struct nfp_net_rx_desc *rxd,
58 struct nfp_net_xsk_rx_buf *xrxbuf,
59 const struct nfp_meta_parsed *meta,
60 unsigned int pkt_len,
61 bool meta_xdp,
62 unsigned int *skbs_polled)
63 {
64 struct nfp_net_r_vector *r_vec = rx_ring->r_vec;
65 struct nfp_net_dp *dp = &r_vec->nfp_net->dp;
66 struct net_device *netdev;
67 struct sk_buff *skb;
68
69 if (likely(!meta->portid)) {
70 netdev = dp->netdev;
71 } else {
72 struct nfp_net *nn = netdev_priv(dp->netdev);
73
74 netdev = nfp_app_dev_get(nn->app, meta->portid, NULL);
75 if (unlikely(!netdev)) {
76 nfp_net_xsk_rx_drop(r_vec, xrxbuf);
77 return;
78 }
79 nfp_repr_inc_rx_stats(netdev, pkt_len);
80 }
81
82 skb = napi_alloc_skb(&r_vec->napi, pkt_len);
83 if (!skb) {
84 nfp_net_xsk_rx_drop(r_vec, xrxbuf);
85 return;
86 }
87 memcpy(skb_put(skb, pkt_len), xrxbuf->xdp->data, pkt_len);
88
89 skb->mark = meta->mark;
90 skb_set_hash(skb, meta->hash, meta->hash_type);
91
92 skb_record_rx_queue(skb, rx_ring->idx);
93 skb->protocol = eth_type_trans(skb, netdev);
94
95 nfp_nfd3_rx_csum(dp, r_vec, rxd, meta, skb);
96
97 if (rxd->rxd.flags & PCIE_DESC_RX_VLAN)
98 __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
99 le16_to_cpu(rxd->rxd.vlan));
100 if (meta_xdp)
101 skb_metadata_set(skb,
102 xrxbuf->xdp->data - xrxbuf->xdp->data_meta);
103
104 napi_gro_receive(&rx_ring->r_vec->napi, skb);
105
106 nfp_net_xsk_rx_free(xrxbuf);
107
108 (*skbs_polled)++;
109 }
110
111 static unsigned int
nfp_nfd3_xsk_rx(struct nfp_net_rx_ring * rx_ring,int budget,unsigned int * skbs_polled)112 nfp_nfd3_xsk_rx(struct nfp_net_rx_ring *rx_ring, int budget,
113 unsigned int *skbs_polled)
114 {
115 struct nfp_net_r_vector *r_vec = rx_ring->r_vec;
116 struct nfp_net_dp *dp = &r_vec->nfp_net->dp;
117 struct nfp_net_tx_ring *tx_ring;
118 struct bpf_prog *xdp_prog;
119 bool xdp_redir = false;
120 int pkts_polled = 0;
121
122 xdp_prog = READ_ONCE(dp->xdp_prog);
123 tx_ring = r_vec->xdp_ring;
124
125 while (pkts_polled < budget) {
126 unsigned int meta_len, data_len, pkt_len, pkt_off;
127 struct nfp_net_xsk_rx_buf *xrxbuf;
128 struct nfp_net_rx_desc *rxd;
129 struct nfp_meta_parsed meta;
130 int idx, act;
131
132 idx = D_IDX(rx_ring, rx_ring->rd_p);
133
134 rxd = &rx_ring->rxds[idx];
135 if (!(rxd->rxd.meta_len_dd & PCIE_DESC_RX_DD))
136 break;
137
138 rx_ring->rd_p++;
139 pkts_polled++;
140
141 xrxbuf = &rx_ring->xsk_rxbufs[idx];
142
143 /* If starved of buffers "drop" it and scream. */
144 if (rx_ring->rd_p >= rx_ring->wr_p) {
145 nn_dp_warn(dp, "Starved of RX buffers\n");
146 nfp_net_xsk_rx_drop(r_vec, xrxbuf);
147 break;
148 }
149
150 /* Memory barrier to ensure that we won't do other reads
151 * before the DD bit.
152 */
153 dma_rmb();
154
155 memset(&meta, 0, sizeof(meta));
156
157 /* Only supporting AF_XDP with dynamic metadata so buffer layout
158 * is always:
159 *
160 * ---------------------------------------------------------
161 * | off | metadata | packet | XXXX |
162 * ---------------------------------------------------------
163 */
164 meta_len = rxd->rxd.meta_len_dd & PCIE_DESC_RX_META_LEN_MASK;
165 data_len = le16_to_cpu(rxd->rxd.data_len);
166 pkt_len = data_len - meta_len;
167
168 if (unlikely(meta_len > NFP_NET_MAX_PREPEND)) {
169 nn_dp_warn(dp, "Oversized RX packet metadata %u\n",
170 meta_len);
171 nfp_net_xsk_rx_drop(r_vec, xrxbuf);
172 continue;
173 }
174
175 /* Stats update. */
176 u64_stats_update_begin(&r_vec->rx_sync);
177 r_vec->rx_pkts++;
178 r_vec->rx_bytes += pkt_len;
179 u64_stats_update_end(&r_vec->rx_sync);
180
181 xrxbuf->xdp->data += meta_len;
182 xrxbuf->xdp->data_end = xrxbuf->xdp->data + pkt_len;
183 xdp_set_data_meta_invalid(xrxbuf->xdp);
184 xsk_buff_dma_sync_for_cpu(xrxbuf->xdp, r_vec->xsk_pool);
185 net_prefetch(xrxbuf->xdp->data);
186
187 if (meta_len) {
188 if (unlikely(nfp_nfd3_parse_meta(dp->netdev, &meta,
189 xrxbuf->xdp->data -
190 meta_len,
191 xrxbuf->xdp->data,
192 pkt_len, meta_len))) {
193 nn_dp_warn(dp, "Invalid RX packet metadata\n");
194 nfp_net_xsk_rx_drop(r_vec, xrxbuf);
195 continue;
196 }
197
198 if (unlikely(meta.portid)) {
199 struct nfp_net *nn = netdev_priv(dp->netdev);
200
201 if (meta.portid != NFP_META_PORT_ID_CTRL) {
202 nfp_nfd3_xsk_rx_skb(rx_ring, rxd,
203 xrxbuf, &meta,
204 pkt_len, false,
205 skbs_polled);
206 continue;
207 }
208
209 nfp_app_ctrl_rx_raw(nn->app, xrxbuf->xdp->data,
210 pkt_len);
211 nfp_net_xsk_rx_free(xrxbuf);
212 continue;
213 }
214 }
215
216 act = bpf_prog_run_xdp(xdp_prog, xrxbuf->xdp);
217
218 pkt_len = xrxbuf->xdp->data_end - xrxbuf->xdp->data;
219 pkt_off = xrxbuf->xdp->data - xrxbuf->xdp->data_hard_start;
220
221 switch (act) {
222 case XDP_PASS:
223 nfp_nfd3_xsk_rx_skb(rx_ring, rxd, xrxbuf, &meta, pkt_len,
224 true, skbs_polled);
225 break;
226 case XDP_TX:
227 if (!nfp_nfd3_xsk_tx_xdp(dp, r_vec, rx_ring, tx_ring,
228 xrxbuf, pkt_len, pkt_off))
229 nfp_net_xsk_rx_drop(r_vec, xrxbuf);
230 else
231 nfp_net_xsk_rx_unstash(xrxbuf);
232 break;
233 case XDP_REDIRECT:
234 if (xdp_do_redirect(dp->netdev, xrxbuf->xdp, xdp_prog)) {
235 nfp_net_xsk_rx_drop(r_vec, xrxbuf);
236 } else {
237 nfp_net_xsk_rx_unstash(xrxbuf);
238 xdp_redir = true;
239 }
240 break;
241 default:
242 bpf_warn_invalid_xdp_action(dp->netdev, xdp_prog, act);
243 fallthrough;
244 case XDP_ABORTED:
245 trace_xdp_exception(dp->netdev, xdp_prog, act);
246 fallthrough;
247 case XDP_DROP:
248 nfp_net_xsk_rx_drop(r_vec, xrxbuf);
249 break;
250 }
251 }
252
253 nfp_net_xsk_rx_ring_fill_freelist(r_vec->rx_ring);
254
255 if (xdp_redir)
256 xdp_do_flush_map();
257
258 if (tx_ring->wr_ptr_add)
259 nfp_net_tx_xmit_more_flush(tx_ring);
260
261 return pkts_polled;
262 }
263
nfp_nfd3_xsk_tx_free(struct nfp_nfd3_tx_buf * txbuf)264 void nfp_nfd3_xsk_tx_free(struct nfp_nfd3_tx_buf *txbuf)
265 {
266 xsk_buff_free(txbuf->xdp);
267
268 txbuf->dma_addr = 0;
269 txbuf->xdp = NULL;
270 }
271
nfp_nfd3_xsk_complete(struct nfp_net_tx_ring * tx_ring)272 static bool nfp_nfd3_xsk_complete(struct nfp_net_tx_ring *tx_ring)
273 {
274 struct nfp_net_r_vector *r_vec = tx_ring->r_vec;
275 u32 done_pkts = 0, done_bytes = 0, reused = 0;
276 bool done_all;
277 int idx, todo;
278 u32 qcp_rd_p;
279
280 if (tx_ring->wr_p == tx_ring->rd_p)
281 return true;
282
283 /* Work out how many descriptors have been transmitted. */
284 qcp_rd_p = nfp_qcp_rd_ptr_read(tx_ring->qcp_q);
285
286 if (qcp_rd_p == tx_ring->qcp_rd_p)
287 return true;
288
289 todo = D_IDX(tx_ring, qcp_rd_p - tx_ring->qcp_rd_p);
290
291 done_all = todo <= NFP_NET_XDP_MAX_COMPLETE;
292 todo = min(todo, NFP_NET_XDP_MAX_COMPLETE);
293
294 tx_ring->qcp_rd_p = D_IDX(tx_ring, tx_ring->qcp_rd_p + todo);
295
296 done_pkts = todo;
297 while (todo--) {
298 struct nfp_nfd3_tx_buf *txbuf;
299
300 idx = D_IDX(tx_ring, tx_ring->rd_p);
301 tx_ring->rd_p++;
302
303 txbuf = &tx_ring->txbufs[idx];
304 if (unlikely(!txbuf->real_len))
305 continue;
306
307 done_bytes += txbuf->real_len;
308 txbuf->real_len = 0;
309
310 if (txbuf->is_xsk_tx) {
311 nfp_nfd3_xsk_tx_free(txbuf);
312 reused++;
313 }
314 }
315
316 u64_stats_update_begin(&r_vec->tx_sync);
317 r_vec->tx_bytes += done_bytes;
318 r_vec->tx_pkts += done_pkts;
319 u64_stats_update_end(&r_vec->tx_sync);
320
321 xsk_tx_completed(r_vec->xsk_pool, done_pkts - reused);
322
323 WARN_ONCE(tx_ring->wr_p - tx_ring->rd_p > tx_ring->cnt,
324 "XDP TX ring corruption rd_p=%u wr_p=%u cnt=%u\n",
325 tx_ring->rd_p, tx_ring->wr_p, tx_ring->cnt);
326
327 return done_all;
328 }
329
nfp_nfd3_xsk_tx(struct nfp_net_tx_ring * tx_ring)330 static void nfp_nfd3_xsk_tx(struct nfp_net_tx_ring *tx_ring)
331 {
332 struct nfp_net_r_vector *r_vec = tx_ring->r_vec;
333 struct xdp_desc desc[NFP_NET_XSK_TX_BATCH];
334 struct xsk_buff_pool *xsk_pool;
335 struct nfp_nfd3_tx_desc *txd;
336 u32 pkts = 0, wr_idx;
337 u32 i, got;
338
339 xsk_pool = r_vec->xsk_pool;
340
341 while (nfp_net_tx_space(tx_ring) >= NFP_NET_XSK_TX_BATCH) {
342 for (i = 0; i < NFP_NET_XSK_TX_BATCH; i++)
343 if (!xsk_tx_peek_desc(xsk_pool, &desc[i]))
344 break;
345 got = i;
346 if (!got)
347 break;
348
349 wr_idx = D_IDX(tx_ring, tx_ring->wr_p + i);
350 prefetchw(&tx_ring->txds[wr_idx]);
351
352 for (i = 0; i < got; i++)
353 xsk_buff_raw_dma_sync_for_device(xsk_pool, desc[i].addr,
354 desc[i].len);
355
356 for (i = 0; i < got; i++) {
357 wr_idx = D_IDX(tx_ring, tx_ring->wr_p + i);
358
359 tx_ring->txbufs[wr_idx].real_len = desc[i].len;
360 tx_ring->txbufs[wr_idx].is_xsk_tx = false;
361
362 /* Build TX descriptor. */
363 txd = &tx_ring->txds[wr_idx];
364 nfp_desc_set_dma_addr(txd,
365 xsk_buff_raw_get_dma(xsk_pool,
366 desc[i].addr
367 ));
368 txd->offset_eop = NFD3_DESC_TX_EOP;
369 txd->dma_len = cpu_to_le16(desc[i].len);
370 txd->data_len = cpu_to_le16(desc[i].len);
371 }
372
373 tx_ring->wr_p += got;
374 pkts += got;
375 }
376
377 if (!pkts)
378 return;
379
380 xsk_tx_release(xsk_pool);
381 /* Ensure all records are visible before incrementing write counter. */
382 wmb();
383 nfp_qcp_wr_ptr_add(tx_ring->qcp_q, pkts);
384 }
385
nfp_nfd3_xsk_poll(struct napi_struct * napi,int budget)386 int nfp_nfd3_xsk_poll(struct napi_struct *napi, int budget)
387 {
388 struct nfp_net_r_vector *r_vec =
389 container_of(napi, struct nfp_net_r_vector, napi);
390 unsigned int pkts_polled, skbs = 0;
391
392 pkts_polled = nfp_nfd3_xsk_rx(r_vec->rx_ring, budget, &skbs);
393
394 if (pkts_polled < budget) {
395 if (r_vec->tx_ring)
396 nfp_nfd3_tx_complete(r_vec->tx_ring, budget);
397
398 if (!nfp_nfd3_xsk_complete(r_vec->xdp_ring))
399 pkts_polled = budget;
400
401 nfp_nfd3_xsk_tx(r_vec->xdp_ring);
402
403 if (pkts_polled < budget && napi_complete_done(napi, skbs))
404 nfp_net_irq_unmask(r_vec->nfp_net, r_vec->irq_entry);
405 }
406
407 return pkts_polled;
408 }
409