1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2019, Intel Corporation. */
3
4 #include <linux/filter.h>
5
6 #include "ice_txrx_lib.h"
7 #include "ice_eswitch.h"
8 #include "ice_lib.h"
9
10 /**
11 * ice_release_rx_desc - Store the new tail and head values
12 * @rx_ring: ring to bump
13 * @val: new head index
14 */
ice_release_rx_desc(struct ice_rx_ring * rx_ring,u16 val)15 void ice_release_rx_desc(struct ice_rx_ring *rx_ring, u16 val)
16 {
17 u16 prev_ntu = rx_ring->next_to_use & ~0x7;
18
19 rx_ring->next_to_use = val;
20
21 /* update next to alloc since we have filled the ring */
22 rx_ring->next_to_alloc = val;
23
24 /* QRX_TAIL will be updated with any tail value, but hardware ignores
25 * the lower 3 bits. This makes it so we only bump tail on meaningful
26 * boundaries. Also, this allows us to bump tail on intervals of 8 up to
27 * the budget depending on the current traffic load.
28 */
29 val &= ~0x7;
30 if (prev_ntu != val) {
31 /* Force memory writes to complete before letting h/w
32 * know there are new descriptors to fetch. (Only
33 * applicable for weak-ordered memory model archs,
34 * such as IA-64).
35 */
36 wmb();
37 writel(val, rx_ring->tail);
38 }
39 }
40
41 /**
42 * ice_ptype_to_htype - get a hash type
43 * @ptype: the ptype value from the descriptor
44 *
45 * Returns appropriate hash type (such as PKT_HASH_TYPE_L2/L3/L4) to be used by
46 * skb_set_hash based on PTYPE as parsed by HW Rx pipeline and is part of
47 * Rx desc.
48 */
ice_ptype_to_htype(u16 ptype)49 static enum pkt_hash_types ice_ptype_to_htype(u16 ptype)
50 {
51 struct ice_rx_ptype_decoded decoded = ice_decode_rx_desc_ptype(ptype);
52
53 if (!decoded.known)
54 return PKT_HASH_TYPE_NONE;
55 if (decoded.payload_layer == ICE_RX_PTYPE_PAYLOAD_LAYER_PAY4)
56 return PKT_HASH_TYPE_L4;
57 if (decoded.payload_layer == ICE_RX_PTYPE_PAYLOAD_LAYER_PAY3)
58 return PKT_HASH_TYPE_L3;
59 if (decoded.outer_ip == ICE_RX_PTYPE_OUTER_L2)
60 return PKT_HASH_TYPE_L2;
61
62 return PKT_HASH_TYPE_NONE;
63 }
64
65 /**
66 * ice_rx_hash - set the hash value in the skb
67 * @rx_ring: descriptor ring
68 * @rx_desc: specific descriptor
69 * @skb: pointer to current skb
70 * @rx_ptype: the ptype value from the descriptor
71 */
72 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)73 ice_rx_hash(struct ice_rx_ring *rx_ring, union ice_32b_rx_flex_desc *rx_desc,
74 struct sk_buff *skb, u16 rx_ptype)
75 {
76 struct ice_32b_rx_flex_desc_nic *nic_mdid;
77 u32 hash;
78
79 if (!(rx_ring->netdev->features & NETIF_F_RXHASH))
80 return;
81
82 if (rx_desc->wb.rxdid != ICE_RXDID_FLEX_NIC)
83 return;
84
85 nic_mdid = (struct ice_32b_rx_flex_desc_nic *)rx_desc;
86 hash = le32_to_cpu(nic_mdid->rss_hash);
87 skb_set_hash(skb, hash, ice_ptype_to_htype(rx_ptype));
88 }
89
90 /**
91 * ice_rx_csum - Indicate in skb if checksum is good
92 * @ring: the ring we care about
93 * @skb: skb currently being received and modified
94 * @rx_desc: the receive descriptor
95 * @ptype: the packet type decoded by hardware
96 *
97 * skb->protocol must be set before this function is called
98 */
99 static void
ice_rx_csum(struct ice_rx_ring * ring,struct sk_buff * skb,union ice_32b_rx_flex_desc * rx_desc,u16 ptype)100 ice_rx_csum(struct ice_rx_ring *ring, struct sk_buff *skb,
101 union ice_32b_rx_flex_desc *rx_desc, u16 ptype)
102 {
103 struct ice_rx_ptype_decoded decoded;
104 u16 rx_status0, rx_status1;
105 bool ipv4, ipv6;
106
107 rx_status0 = le16_to_cpu(rx_desc->wb.status_error0);
108 rx_status1 = le16_to_cpu(rx_desc->wb.status_error1);
109
110 decoded = ice_decode_rx_desc_ptype(ptype);
111
112 /* Start with CHECKSUM_NONE and by default csum_level = 0 */
113 skb->ip_summed = CHECKSUM_NONE;
114 skb_checksum_none_assert(skb);
115
116 /* check if Rx checksum is enabled */
117 if (!(ring->netdev->features & NETIF_F_RXCSUM))
118 return;
119
120 /* check if HW has decoded the packet and checksum */
121 if (!(rx_status0 & BIT(ICE_RX_FLEX_DESC_STATUS0_L3L4P_S)))
122 return;
123
124 if (!(decoded.known && decoded.outer_ip))
125 return;
126
127 ipv4 = (decoded.outer_ip == ICE_RX_PTYPE_OUTER_IP) &&
128 (decoded.outer_ip_ver == ICE_RX_PTYPE_OUTER_IPV4);
129 ipv6 = (decoded.outer_ip == ICE_RX_PTYPE_OUTER_IP) &&
130 (decoded.outer_ip_ver == ICE_RX_PTYPE_OUTER_IPV6);
131
132 if (ipv4 && (rx_status0 & (BIT(ICE_RX_FLEX_DESC_STATUS0_XSUM_IPE_S) |
133 BIT(ICE_RX_FLEX_DESC_STATUS0_XSUM_EIPE_S))))
134 goto checksum_fail;
135
136 if (ipv6 && (rx_status0 & (BIT(ICE_RX_FLEX_DESC_STATUS0_IPV6EXADD_S))))
137 goto checksum_fail;
138
139 /* check for L4 errors and handle packets that were not able to be
140 * checksummed due to arrival speed
141 */
142 if (rx_status0 & BIT(ICE_RX_FLEX_DESC_STATUS0_XSUM_L4E_S))
143 goto checksum_fail;
144
145 /* check for outer UDP checksum error in tunneled packets */
146 if ((rx_status1 & BIT(ICE_RX_FLEX_DESC_STATUS1_NAT_S)) &&
147 (rx_status0 & BIT(ICE_RX_FLEX_DESC_STATUS0_XSUM_EUDPE_S)))
148 goto checksum_fail;
149
150 /* If there is an outer header present that might contain a checksum
151 * we need to bump the checksum level by 1 to reflect the fact that
152 * we are indicating we validated the inner checksum.
153 */
154 if (decoded.tunnel_type >= ICE_RX_PTYPE_TUNNEL_IP_GRENAT)
155 skb->csum_level = 1;
156
157 /* Only report checksum unnecessary for TCP, UDP, or SCTP */
158 switch (decoded.inner_prot) {
159 case ICE_RX_PTYPE_INNER_PROT_TCP:
160 case ICE_RX_PTYPE_INNER_PROT_UDP:
161 case ICE_RX_PTYPE_INNER_PROT_SCTP:
162 skb->ip_summed = CHECKSUM_UNNECESSARY;
163 break;
164 default:
165 break;
166 }
167 return;
168
169 checksum_fail:
170 ring->vsi->back->hw_csum_rx_error++;
171 }
172
173 /**
174 * ice_process_skb_fields - Populate skb header fields from Rx descriptor
175 * @rx_ring: Rx descriptor ring packet is being transacted on
176 * @rx_desc: pointer to the EOP Rx descriptor
177 * @skb: pointer to current skb being populated
178 * @ptype: the packet type decoded by hardware
179 *
180 * This function checks the ring, descriptor, and packet information in
181 * order to populate the hash, checksum, VLAN, protocol, and
182 * other fields within the skb.
183 */
184 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)185 ice_process_skb_fields(struct ice_rx_ring *rx_ring,
186 union ice_32b_rx_flex_desc *rx_desc,
187 struct sk_buff *skb, u16 ptype)
188 {
189 ice_rx_hash(rx_ring, rx_desc, skb, ptype);
190
191 /* modifies the skb - consumes the enet header */
192 skb->protocol = eth_type_trans(skb, rx_ring->netdev);
193
194 ice_rx_csum(rx_ring, skb, rx_desc, ptype);
195
196 if (rx_ring->ptp_rx)
197 ice_ptp_rx_hwtstamp(rx_ring, rx_desc, skb);
198 }
199
200 /**
201 * ice_receive_skb - Send a completed packet up the stack
202 * @rx_ring: Rx ring in play
203 * @skb: packet to send up
204 * @vlan_tag: VLAN tag for packet
205 *
206 * This function sends the completed packet (via. skb) up the stack using
207 * gro receive functions (with/without VLAN tag)
208 */
209 void
ice_receive_skb(struct ice_rx_ring * rx_ring,struct sk_buff * skb,u16 vlan_tag)210 ice_receive_skb(struct ice_rx_ring *rx_ring, struct sk_buff *skb, u16 vlan_tag)
211 {
212 netdev_features_t features = rx_ring->netdev->features;
213 bool non_zero_vlan = !!(vlan_tag & VLAN_VID_MASK);
214
215 if ((features & NETIF_F_HW_VLAN_CTAG_RX) && non_zero_vlan)
216 __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), vlan_tag);
217 else if ((features & NETIF_F_HW_VLAN_STAG_RX) && non_zero_vlan)
218 __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021AD), vlan_tag);
219
220 napi_gro_receive(&rx_ring->q_vector->napi, skb);
221 }
222
223 /**
224 * ice_clean_xdp_tx_buf - Free and unmap XDP Tx buffer
225 * @dev: device for DMA mapping
226 * @tx_buf: Tx buffer to clean
227 * @bq: XDP bulk flush struct
228 */
229 static void
ice_clean_xdp_tx_buf(struct device * dev,struct ice_tx_buf * tx_buf,struct xdp_frame_bulk * bq)230 ice_clean_xdp_tx_buf(struct device *dev, struct ice_tx_buf *tx_buf,
231 struct xdp_frame_bulk *bq)
232 {
233 dma_unmap_single(dev, dma_unmap_addr(tx_buf, dma),
234 dma_unmap_len(tx_buf, len), DMA_TO_DEVICE);
235 dma_unmap_len_set(tx_buf, len, 0);
236
237 switch (tx_buf->type) {
238 case ICE_TX_BUF_XDP_TX:
239 page_frag_free(tx_buf->raw_buf);
240 break;
241 case ICE_TX_BUF_XDP_XMIT:
242 xdp_return_frame_bulk(tx_buf->xdpf, bq);
243 break;
244 }
245
246 tx_buf->type = ICE_TX_BUF_EMPTY;
247 }
248
249 /**
250 * ice_clean_xdp_irq - Reclaim resources after transmit completes on XDP ring
251 * @xdp_ring: XDP ring to clean
252 */
ice_clean_xdp_irq(struct ice_tx_ring * xdp_ring)253 static u32 ice_clean_xdp_irq(struct ice_tx_ring *xdp_ring)
254 {
255 int total_bytes = 0, total_pkts = 0;
256 struct device *dev = xdp_ring->dev;
257 u32 ntc = xdp_ring->next_to_clean;
258 struct ice_tx_desc *tx_desc;
259 u32 cnt = xdp_ring->count;
260 struct xdp_frame_bulk bq;
261 u32 frags, xdp_tx = 0;
262 u32 ready_frames = 0;
263 u32 idx;
264 u32 ret;
265
266 idx = xdp_ring->tx_buf[ntc].rs_idx;
267 tx_desc = ICE_TX_DESC(xdp_ring, idx);
268 if (tx_desc->cmd_type_offset_bsz &
269 cpu_to_le64(ICE_TX_DESC_DTYPE_DESC_DONE)) {
270 if (idx >= ntc)
271 ready_frames = idx - ntc + 1;
272 else
273 ready_frames = idx + cnt - ntc + 1;
274 }
275
276 if (unlikely(!ready_frames))
277 return 0;
278 ret = ready_frames;
279
280 xdp_frame_bulk_init(&bq);
281 rcu_read_lock(); /* xdp_return_frame_bulk() */
282
283 while (ready_frames) {
284 struct ice_tx_buf *tx_buf = &xdp_ring->tx_buf[ntc];
285 struct ice_tx_buf *head = tx_buf;
286
287 /* bytecount holds size of head + frags */
288 total_bytes += tx_buf->bytecount;
289 frags = tx_buf->nr_frags;
290 total_pkts++;
291 /* count head + frags */
292 ready_frames -= frags + 1;
293 xdp_tx++;
294
295 ntc++;
296 if (ntc == cnt)
297 ntc = 0;
298
299 for (int i = 0; i < frags; i++) {
300 tx_buf = &xdp_ring->tx_buf[ntc];
301
302 ice_clean_xdp_tx_buf(dev, tx_buf, &bq);
303 ntc++;
304 if (ntc == cnt)
305 ntc = 0;
306 }
307
308 ice_clean_xdp_tx_buf(dev, head, &bq);
309 }
310
311 xdp_flush_frame_bulk(&bq);
312 rcu_read_unlock();
313
314 tx_desc->cmd_type_offset_bsz = 0;
315 xdp_ring->next_to_clean = ntc;
316 xdp_ring->xdp_tx_active -= xdp_tx;
317 ice_update_tx_ring_stats(xdp_ring, total_pkts, total_bytes);
318
319 return ret;
320 }
321
322 /**
323 * __ice_xmit_xdp_ring - submit frame to XDP ring for transmission
324 * @xdp: XDP buffer to be placed onto Tx descriptors
325 * @xdp_ring: XDP ring for transmission
326 * @frame: whether this comes from .ndo_xdp_xmit()
327 */
__ice_xmit_xdp_ring(struct xdp_buff * xdp,struct ice_tx_ring * xdp_ring,bool frame)328 int __ice_xmit_xdp_ring(struct xdp_buff *xdp, struct ice_tx_ring *xdp_ring,
329 bool frame)
330 {
331 struct skb_shared_info *sinfo = NULL;
332 u32 size = xdp->data_end - xdp->data;
333 struct device *dev = xdp_ring->dev;
334 u32 ntu = xdp_ring->next_to_use;
335 struct ice_tx_desc *tx_desc;
336 struct ice_tx_buf *tx_head;
337 struct ice_tx_buf *tx_buf;
338 u32 cnt = xdp_ring->count;
339 void *data = xdp->data;
340 u32 nr_frags = 0;
341 u32 free_space;
342 u32 frag = 0;
343
344 free_space = ICE_DESC_UNUSED(xdp_ring);
345 if (free_space < ICE_RING_QUARTER(xdp_ring))
346 free_space += ice_clean_xdp_irq(xdp_ring);
347
348 if (unlikely(!free_space))
349 goto busy;
350
351 if (unlikely(xdp_buff_has_frags(xdp))) {
352 sinfo = xdp_get_shared_info_from_buff(xdp);
353 nr_frags = sinfo->nr_frags;
354 if (free_space < nr_frags + 1)
355 goto busy;
356 }
357
358 tx_desc = ICE_TX_DESC(xdp_ring, ntu);
359 tx_head = &xdp_ring->tx_buf[ntu];
360 tx_buf = tx_head;
361
362 for (;;) {
363 dma_addr_t dma;
364
365 dma = dma_map_single(dev, data, size, DMA_TO_DEVICE);
366 if (dma_mapping_error(dev, dma))
367 goto dma_unmap;
368
369 /* record length, and DMA address */
370 dma_unmap_len_set(tx_buf, len, size);
371 dma_unmap_addr_set(tx_buf, dma, dma);
372
373 if (frame) {
374 tx_buf->type = ICE_TX_BUF_FRAG;
375 } else {
376 tx_buf->type = ICE_TX_BUF_XDP_TX;
377 tx_buf->raw_buf = data;
378 }
379
380 tx_desc->buf_addr = cpu_to_le64(dma);
381 tx_desc->cmd_type_offset_bsz = ice_build_ctob(0, 0, size, 0);
382
383 ntu++;
384 if (ntu == cnt)
385 ntu = 0;
386
387 if (frag == nr_frags)
388 break;
389
390 tx_desc = ICE_TX_DESC(xdp_ring, ntu);
391 tx_buf = &xdp_ring->tx_buf[ntu];
392
393 data = skb_frag_address(&sinfo->frags[frag]);
394 size = skb_frag_size(&sinfo->frags[frag]);
395 frag++;
396 }
397
398 /* store info about bytecount and frag count in first desc */
399 tx_head->bytecount = xdp_get_buff_len(xdp);
400 tx_head->nr_frags = nr_frags;
401
402 if (frame) {
403 tx_head->type = ICE_TX_BUF_XDP_XMIT;
404 tx_head->xdpf = xdp->data_hard_start;
405 }
406
407 /* update last descriptor from a frame with EOP */
408 tx_desc->cmd_type_offset_bsz |=
409 cpu_to_le64(ICE_TX_DESC_CMD_EOP << ICE_TXD_QW1_CMD_S);
410
411 xdp_ring->xdp_tx_active++;
412 xdp_ring->next_to_use = ntu;
413
414 return ICE_XDP_TX;
415
416 dma_unmap:
417 for (;;) {
418 tx_buf = &xdp_ring->tx_buf[ntu];
419 dma_unmap_page(dev, dma_unmap_addr(tx_buf, dma),
420 dma_unmap_len(tx_buf, len), DMA_TO_DEVICE);
421 dma_unmap_len_set(tx_buf, len, 0);
422 if (tx_buf == tx_head)
423 break;
424
425 if (!ntu)
426 ntu += cnt;
427 ntu--;
428 }
429 return ICE_XDP_CONSUMED;
430
431 busy:
432 xdp_ring->ring_stats->tx_stats.tx_busy++;
433
434 return ICE_XDP_CONSUMED;
435 }
436
437 /**
438 * ice_finalize_xdp_rx - Bump XDP Tx tail and/or flush redirect map
439 * @xdp_ring: XDP ring
440 * @xdp_res: Result of the receive batch
441 * @first_idx: index to write from caller
442 *
443 * This function bumps XDP Tx tail and/or flush redirect map, and
444 * should be called when a batch of packets has been processed in the
445 * napi loop.
446 */
ice_finalize_xdp_rx(struct ice_tx_ring * xdp_ring,unsigned int xdp_res,u32 first_idx)447 void ice_finalize_xdp_rx(struct ice_tx_ring *xdp_ring, unsigned int xdp_res,
448 u32 first_idx)
449 {
450 struct ice_tx_buf *tx_buf = &xdp_ring->tx_buf[first_idx];
451
452 if (xdp_res & ICE_XDP_REDIR)
453 xdp_do_flush_map();
454
455 if (xdp_res & ICE_XDP_TX) {
456 if (static_branch_unlikely(&ice_xdp_locking_key))
457 spin_lock(&xdp_ring->tx_lock);
458 /* store index of descriptor with RS bit set in the first
459 * ice_tx_buf of given NAPI batch
460 */
461 tx_buf->rs_idx = ice_set_rs_bit(xdp_ring);
462 ice_xdp_ring_update_tail(xdp_ring);
463 if (static_branch_unlikely(&ice_xdp_locking_key))
464 spin_unlock(&xdp_ring->tx_lock);
465 }
466 }
467
