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1/* Broadcom NetXtreme-C/E network driver.
2 *
3 * Copyright (c) 2016-2017 Broadcom Limited
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation.
8 */
9#include <linux/kernel.h>
10#include <linux/errno.h>
11#include <linux/pci.h>
12#include <linux/netdevice.h>
13#include <linux/etherdevice.h>
14#include <linux/if_vlan.h>
15#include <linux/bpf.h>
16#include <linux/bpf_trace.h>
17#include <linux/filter.h>
18#include <net/page_pool/helpers.h>
19#include "bnxt_hsi.h"
20#include "bnxt.h"
21#include "bnxt_xdp.h"
22
23DEFINE_STATIC_KEY_FALSE(bnxt_xdp_locking_key);
24
25struct bnxt_sw_tx_bd *bnxt_xmit_bd(struct bnxt *bp,
26 struct bnxt_tx_ring_info *txr,
27 dma_addr_t mapping, u32 len,
28 struct xdp_buff *xdp)
29{
30 struct skb_shared_info *sinfo;
31 struct bnxt_sw_tx_bd *tx_buf;
32 struct tx_bd *txbd;
33 int num_frags = 0;
34 u32 flags;
35 u16 prod;
36 int i;
37
38 if (xdp && xdp_buff_has_frags(xdp)) {
39 sinfo = xdp_get_shared_info_from_buff(xdp);
40 num_frags = sinfo->nr_frags;
41 }
42
43 /* fill up the first buffer */
44 prod = txr->tx_prod;
45 tx_buf = &txr->tx_buf_ring[RING_TX(bp, prod)];
46 tx_buf->nr_frags = num_frags;
47 if (xdp)
48 tx_buf->page = virt_to_head_page(xdp->data);
49
50 txbd = &txr->tx_desc_ring[TX_RING(bp, prod)][TX_IDX(prod)];
51 flags = (len << TX_BD_LEN_SHIFT) |
52 ((num_frags + 1) << TX_BD_FLAGS_BD_CNT_SHIFT) |
53 bnxt_lhint_arr[len >> 9];
54 txbd->tx_bd_len_flags_type = cpu_to_le32(flags);
55 txbd->tx_bd_opaque = SET_TX_OPAQUE(bp, txr, prod, 1 + num_frags);
56 txbd->tx_bd_haddr = cpu_to_le64(mapping);
57
58 /* now let us fill up the frags into the next buffers */
59 for (i = 0; i < num_frags ; i++) {
60 skb_frag_t *frag = &sinfo->frags[i];
61 struct bnxt_sw_tx_bd *frag_tx_buf;
62 dma_addr_t frag_mapping;
63 int frag_len;
64
65 prod = NEXT_TX(prod);
66 WRITE_ONCE(txr->tx_prod, prod);
67
68 /* first fill up the first buffer */
69 frag_tx_buf = &txr->tx_buf_ring[RING_TX(bp, prod)];
70 frag_tx_buf->page = skb_frag_page(frag);
71
72 txbd = &txr->tx_desc_ring[TX_RING(bp, prod)][TX_IDX(prod)];
73
74 frag_len = skb_frag_size(frag);
75 flags = frag_len << TX_BD_LEN_SHIFT;
76 txbd->tx_bd_len_flags_type = cpu_to_le32(flags);
77 frag_mapping = page_pool_get_dma_addr(skb_frag_page(frag)) +
78 skb_frag_off(frag);
79 txbd->tx_bd_haddr = cpu_to_le64(frag_mapping);
80
81 len = frag_len;
82 }
83
84 flags &= ~TX_BD_LEN;
85 txbd->tx_bd_len_flags_type = cpu_to_le32(((len) << TX_BD_LEN_SHIFT) | flags |
86 TX_BD_FLAGS_PACKET_END);
87 /* Sync TX BD */
88 wmb();
89 prod = NEXT_TX(prod);
90 WRITE_ONCE(txr->tx_prod, prod);
91
92 return tx_buf;
93}
94
95static void __bnxt_xmit_xdp(struct bnxt *bp, struct bnxt_tx_ring_info *txr,
96 dma_addr_t mapping, u32 len, u16 rx_prod,
97 struct xdp_buff *xdp)
98{
99 struct bnxt_sw_tx_bd *tx_buf;
100
101 tx_buf = bnxt_xmit_bd(bp, txr, mapping, len, xdp);
102 tx_buf->rx_prod = rx_prod;
103 tx_buf->action = XDP_TX;
104
105}
106
107static void __bnxt_xmit_xdp_redirect(struct bnxt *bp,
108 struct bnxt_tx_ring_info *txr,
109 dma_addr_t mapping, u32 len,
110 struct xdp_frame *xdpf)
111{
112 struct bnxt_sw_tx_bd *tx_buf;
113
114 tx_buf = bnxt_xmit_bd(bp, txr, mapping, len, NULL);
115 tx_buf->action = XDP_REDIRECT;
116 tx_buf->xdpf = xdpf;
117 dma_unmap_addr_set(tx_buf, mapping, mapping);
118 dma_unmap_len_set(tx_buf, len, 0);
119}
120
121void bnxt_tx_int_xdp(struct bnxt *bp, struct bnxt_napi *bnapi, int budget)
122{
123 struct bnxt_tx_ring_info *txr = bnapi->tx_ring[0];
124 struct bnxt_rx_ring_info *rxr = bnapi->rx_ring;
125 u16 tx_hw_cons = txr->tx_hw_cons;
126 bool rx_doorbell_needed = false;
127 struct bnxt_sw_tx_bd *tx_buf;
128 u16 tx_cons = txr->tx_cons;
129 u16 last_tx_cons = tx_cons;
130 int j, frags;
131
132 if (!budget)
133 return;
134
135 while (RING_TX(bp, tx_cons) != tx_hw_cons) {
136 tx_buf = &txr->tx_buf_ring[RING_TX(bp, tx_cons)];
137
138 if (tx_buf->action == XDP_REDIRECT) {
139 struct pci_dev *pdev = bp->pdev;
140
141 dma_unmap_single(&pdev->dev,
142 dma_unmap_addr(tx_buf, mapping),
143 dma_unmap_len(tx_buf, len),
144 DMA_TO_DEVICE);
145 xdp_return_frame(tx_buf->xdpf);
146 tx_buf->action = 0;
147 tx_buf->xdpf = NULL;
148 } else if (tx_buf->action == XDP_TX) {
149 tx_buf->action = 0;
150 rx_doorbell_needed = true;
151 last_tx_cons = tx_cons;
152
153 frags = tx_buf->nr_frags;
154 for (j = 0; j < frags; j++) {
155 tx_cons = NEXT_TX(tx_cons);
156 tx_buf = &txr->tx_buf_ring[RING_TX(bp, tx_cons)];
157 page_pool_recycle_direct(rxr->page_pool, tx_buf->page);
158 }
159 } else {
160 bnxt_sched_reset_txr(bp, txr, tx_cons);
161 return;
162 }
163 tx_cons = NEXT_TX(tx_cons);
164 }
165
166 bnapi->events &= ~BNXT_TX_CMP_EVENT;
167 WRITE_ONCE(txr->tx_cons, tx_cons);
168 if (rx_doorbell_needed) {
169 tx_buf = &txr->tx_buf_ring[RING_TX(bp, last_tx_cons)];
170 bnxt_db_write(bp, &rxr->rx_db, tx_buf->rx_prod);
171
172 }
173}
174
175bool bnxt_xdp_attached(struct bnxt *bp, struct bnxt_rx_ring_info *rxr)
176{
177 struct bpf_prog *xdp_prog = READ_ONCE(rxr->xdp_prog);
178
179 return !!xdp_prog;
180}
181
182void bnxt_xdp_buff_init(struct bnxt *bp, struct bnxt_rx_ring_info *rxr,
183 u16 cons, u8 *data_ptr, unsigned int len,
184 struct xdp_buff *xdp)
185{
186 u32 buflen = BNXT_RX_PAGE_SIZE;
187 struct bnxt_sw_rx_bd *rx_buf;
188 struct pci_dev *pdev;
189 dma_addr_t mapping;
190 u32 offset;
191
192 pdev = bp->pdev;
193 rx_buf = &rxr->rx_buf_ring[cons];
194 offset = bp->rx_offset;
195
196 mapping = rx_buf->mapping - bp->rx_dma_offset;
197 dma_sync_single_for_cpu(&pdev->dev, mapping + offset, len, bp->rx_dir);
198
199 xdp_init_buff(xdp, buflen, &rxr->xdp_rxq);
200 xdp_prepare_buff(xdp, data_ptr - offset, offset, len, false);
201}
202
203void bnxt_xdp_buff_frags_free(struct bnxt_rx_ring_info *rxr,
204 struct xdp_buff *xdp)
205{
206 struct skb_shared_info *shinfo;
207 int i;
208
209 if (!xdp || !xdp_buff_has_frags(xdp))
210 return;
211 shinfo = xdp_get_shared_info_from_buff(xdp);
212 for (i = 0; i < shinfo->nr_frags; i++) {
213 struct page *page = skb_frag_page(&shinfo->frags[i]);
214
215 page_pool_recycle_direct(rxr->page_pool, page);
216 }
217 shinfo->nr_frags = 0;
218}
219
220/* returns the following:
221 * true - packet consumed by XDP and new buffer is allocated.
222 * false - packet should be passed to the stack.
223 */
224bool bnxt_rx_xdp(struct bnxt *bp, struct bnxt_rx_ring_info *rxr, u16 cons,
225 struct xdp_buff xdp, struct page *page, u8 **data_ptr,
226 unsigned int *len, u8 *event)
227{
228 struct bpf_prog *xdp_prog = READ_ONCE(rxr->xdp_prog);
229 struct bnxt_tx_ring_info *txr;
230 struct bnxt_sw_rx_bd *rx_buf;
231 struct pci_dev *pdev;
232 dma_addr_t mapping;
233 u32 tx_needed = 1;
234 void *orig_data;
235 u32 tx_avail;
236 u32 offset;
237 u32 act;
238
239 if (!xdp_prog)
240 return false;
241
242 pdev = bp->pdev;
243 offset = bp->rx_offset;
244
245 txr = rxr->bnapi->tx_ring[0];
246 /* BNXT_RX_PAGE_MODE(bp) when XDP enabled */
247 orig_data = xdp.data;
248
249 act = bpf_prog_run_xdp(xdp_prog, &xdp);
250
251 tx_avail = bnxt_tx_avail(bp, txr);
252 /* If the tx ring is not full, we must not update the rx producer yet
253 * because we may still be transmitting on some BDs.
254 */
255 if (tx_avail != bp->tx_ring_size)
256 *event &= ~BNXT_RX_EVENT;
257
258 *len = xdp.data_end - xdp.data;
259 if (orig_data != xdp.data) {
260 offset = xdp.data - xdp.data_hard_start;
261 *data_ptr = xdp.data_hard_start + offset;
262 }
263
264 switch (act) {
265 case XDP_PASS:
266 return false;
267
268 case XDP_TX:
269 rx_buf = &rxr->rx_buf_ring[cons];
270 mapping = rx_buf->mapping - bp->rx_dma_offset;
271 *event &= BNXT_TX_CMP_EVENT;
272
273 if (unlikely(xdp_buff_has_frags(&xdp))) {
274 struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(&xdp);
275
276 tx_needed += sinfo->nr_frags;
277 *event = BNXT_AGG_EVENT;
278 }
279
280 if (tx_avail < tx_needed) {
281 trace_xdp_exception(bp->dev, xdp_prog, act);
282 bnxt_xdp_buff_frags_free(rxr, &xdp);
283 bnxt_reuse_rx_data(rxr, cons, page);
284 return true;
285 }
286
287 dma_sync_single_for_device(&pdev->dev, mapping + offset, *len,
288 bp->rx_dir);
289
290 *event |= BNXT_TX_EVENT;
291 __bnxt_xmit_xdp(bp, txr, mapping + offset, *len,
292 NEXT_RX(rxr->rx_prod), &xdp);
293 bnxt_reuse_rx_data(rxr, cons, page);
294 return true;
295 case XDP_REDIRECT:
296 /* if we are calling this here then we know that the
297 * redirect is coming from a frame received by the
298 * bnxt_en driver.
299 */
300 rx_buf = &rxr->rx_buf_ring[cons];
301 mapping = rx_buf->mapping - bp->rx_dma_offset;
302 dma_unmap_page_attrs(&pdev->dev, mapping,
303 BNXT_RX_PAGE_SIZE, bp->rx_dir,
304 DMA_ATTR_WEAK_ORDERING);
305
306 /* if we are unable to allocate a new buffer, abort and reuse */
307 if (bnxt_alloc_rx_data(bp, rxr, rxr->rx_prod, GFP_ATOMIC)) {
308 trace_xdp_exception(bp->dev, xdp_prog, act);
309 bnxt_xdp_buff_frags_free(rxr, &xdp);
310 bnxt_reuse_rx_data(rxr, cons, page);
311 return true;
312 }
313
314 if (xdp_do_redirect(bp->dev, &xdp, xdp_prog)) {
315 trace_xdp_exception(bp->dev, xdp_prog, act);
316 page_pool_recycle_direct(rxr->page_pool, page);
317 return true;
318 }
319
320 *event |= BNXT_REDIRECT_EVENT;
321 break;
322 default:
323 bpf_warn_invalid_xdp_action(bp->dev, xdp_prog, act);
324 fallthrough;
325 case XDP_ABORTED:
326 trace_xdp_exception(bp->dev, xdp_prog, act);
327 fallthrough;
328 case XDP_DROP:
329 bnxt_xdp_buff_frags_free(rxr, &xdp);
330 bnxt_reuse_rx_data(rxr, cons, page);
331 break;
332 }
333 return true;
334}
335
336int bnxt_xdp_xmit(struct net_device *dev, int num_frames,
337 struct xdp_frame **frames, u32 flags)
338{
339 struct bnxt *bp = netdev_priv(dev);
340 struct bpf_prog *xdp_prog = READ_ONCE(bp->xdp_prog);
341 struct pci_dev *pdev = bp->pdev;
342 struct bnxt_tx_ring_info *txr;
343 dma_addr_t mapping;
344 int nxmit = 0;
345 int ring;
346 int i;
347
348 if (!test_bit(BNXT_STATE_OPEN, &bp->state) ||
349 !bp->tx_nr_rings_xdp ||
350 !xdp_prog)
351 return -EINVAL;
352
353 ring = smp_processor_id() % bp->tx_nr_rings_xdp;
354 txr = &bp->tx_ring[ring];
355
356 if (READ_ONCE(txr->dev_state) == BNXT_DEV_STATE_CLOSING)
357 return -EINVAL;
358
359 if (static_branch_unlikely(&bnxt_xdp_locking_key))
360 spin_lock(&txr->xdp_tx_lock);
361
362 for (i = 0; i < num_frames; i++) {
363 struct xdp_frame *xdp = frames[i];
364
365 if (!bnxt_tx_avail(bp, txr))
366 break;
367
368 mapping = dma_map_single(&pdev->dev, xdp->data, xdp->len,
369 DMA_TO_DEVICE);
370
371 if (dma_mapping_error(&pdev->dev, mapping))
372 break;
373
374 __bnxt_xmit_xdp_redirect(bp, txr, mapping, xdp->len, xdp);
375 nxmit++;
376 }
377
378 if (flags & XDP_XMIT_FLUSH) {
379 /* Sync BD data before updating doorbell */
380 wmb();
381 bnxt_db_write(bp, &txr->tx_db, txr->tx_prod);
382 }
383
384 if (static_branch_unlikely(&bnxt_xdp_locking_key))
385 spin_unlock(&txr->xdp_tx_lock);
386
387 return nxmit;
388}
389
390/* Under rtnl_lock */
391static int bnxt_xdp_set(struct bnxt *bp, struct bpf_prog *prog)
392{
393 struct net_device *dev = bp->dev;
394 int tx_xdp = 0, tx_cp, rc, tc;
395 struct bpf_prog *old;
396
397 if (prog && !prog->aux->xdp_has_frags &&
398 bp->dev->mtu > BNXT_MAX_PAGE_MODE_MTU) {
399 netdev_warn(dev, "MTU %d larger than %d without XDP frag support.\n",
400 bp->dev->mtu, BNXT_MAX_PAGE_MODE_MTU);
401 return -EOPNOTSUPP;
402 }
403 if (!(bp->flags & BNXT_FLAG_SHARED_RINGS)) {
404 netdev_warn(dev, "ethtool rx/tx channels must be combined to support XDP.\n");
405 return -EOPNOTSUPP;
406 }
407 if (prog)
408 tx_xdp = bp->rx_nr_rings;
409
410 tc = bp->num_tc;
411 if (!tc)
412 tc = 1;
413 rc = bnxt_check_rings(bp, bp->tx_nr_rings_per_tc, bp->rx_nr_rings,
414 true, tc, tx_xdp);
415 if (rc) {
416 netdev_warn(dev, "Unable to reserve enough TX rings to support XDP.\n");
417 return rc;
418 }
419 if (netif_running(dev))
420 bnxt_close_nic(bp, true, false);
421
422 old = xchg(&bp->xdp_prog, prog);
423 if (old)
424 bpf_prog_put(old);
425
426 if (prog) {
427 bnxt_set_rx_skb_mode(bp, true);
428 xdp_features_set_redirect_target(dev, true);
429 } else {
430 int rx, tx;
431
432 xdp_features_clear_redirect_target(dev);
433 bnxt_set_rx_skb_mode(bp, false);
434 bnxt_get_max_rings(bp, &rx, &tx, true);
435 if (rx > 1) {
436 bp->flags &= ~BNXT_FLAG_NO_AGG_RINGS;
437 bp->dev->hw_features |= NETIF_F_LRO;
438 }
439 }
440 bp->tx_nr_rings_xdp = tx_xdp;
441 bp->tx_nr_rings = bp->tx_nr_rings_per_tc * tc + tx_xdp;
442 tx_cp = bnxt_num_tx_to_cp(bp, bp->tx_nr_rings);
443 bp->cp_nr_rings = max_t(int, tx_cp, bp->rx_nr_rings);
444 bnxt_set_tpa_flags(bp);
445 bnxt_set_ring_params(bp);
446
447 if (netif_running(dev))
448 return bnxt_open_nic(bp, true, false);
449
450 return 0;
451}
452
453int bnxt_xdp(struct net_device *dev, struct netdev_bpf *xdp)
454{
455 struct bnxt *bp = netdev_priv(dev);
456 int rc;
457
458 switch (xdp->command) {
459 case XDP_SETUP_PROG:
460 rc = bnxt_xdp_set(bp, xdp->prog);
461 break;
462 default:
463 rc = -EINVAL;
464 break;
465 }
466 return rc;
467}
468
469struct sk_buff *
470bnxt_xdp_build_skb(struct bnxt *bp, struct sk_buff *skb, u8 num_frags,
471 struct page_pool *pool, struct xdp_buff *xdp,
472 struct rx_cmp_ext *rxcmp1)
473{
474 struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);
475
476 if (!skb)
477 return NULL;
478 skb_checksum_none_assert(skb);
479 if (RX_CMP_L4_CS_OK(rxcmp1)) {
480 if (bp->dev->features & NETIF_F_RXCSUM) {
481 skb->ip_summed = CHECKSUM_UNNECESSARY;
482 skb->csum_level = RX_CMP_ENCAP(rxcmp1);
483 }
484 }
485 xdp_update_skb_shared_info(skb, num_frags,
486 sinfo->xdp_frags_size,
487 BNXT_RX_PAGE_SIZE * sinfo->nr_frags,
488 xdp_buff_is_frag_pfmemalloc(xdp));
489 return skb;
490}