xref: /linux/drivers/target/iscsi/cxgbit/cxgbit_main.c (revision 24168c5e6dfbdd5b414f048f47f75d64533296ca)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2016 Chelsio Communications, Inc.
4  */
5 
6 #define DRV_NAME "cxgbit"
7 #define DRV_VERSION "1.0.0-ko"
8 #define pr_fmt(fmt) DRV_NAME ": " fmt
9 
10 #include "cxgbit.h"
11 
12 #ifdef CONFIG_CHELSIO_T4_DCB
13 #include <net/dcbevent.h>
14 #include "cxgb4_dcb.h"
15 #endif
16 
17 LIST_HEAD(cdev_list_head);
18 /* cdev list lock */
19 DEFINE_MUTEX(cdev_list_lock);
20 
21 void _cxgbit_free_cdev(struct kref *kref)
22 {
23 	struct cxgbit_device *cdev;
24 
25 	cdev = container_of(kref, struct cxgbit_device, kref);
26 
27 	cxgbi_ppm_release(cdev2ppm(cdev));
28 	kfree(cdev);
29 }
30 
31 static void cxgbit_set_mdsl(struct cxgbit_device *cdev)
32 {
33 	struct cxgb4_lld_info *lldi = &cdev->lldi;
34 	u32 mdsl;
35 
36 #define CXGBIT_T5_MAX_PDU_LEN 16224
37 #define CXGBIT_PDU_NONPAYLOAD_LEN 312 /* 48(BHS) + 256(AHS) + 8(Digest) */
38 	if (is_t5(lldi->adapter_type)) {
39 		mdsl = min_t(u32, lldi->iscsi_iolen - CXGBIT_PDU_NONPAYLOAD_LEN,
40 			     CXGBIT_T5_MAX_PDU_LEN - CXGBIT_PDU_NONPAYLOAD_LEN);
41 	} else {
42 		mdsl = lldi->iscsi_iolen - CXGBIT_PDU_NONPAYLOAD_LEN;
43 		mdsl = min(mdsl, 16384U);
44 	}
45 
46 	mdsl = round_down(mdsl, 4);
47 	mdsl = min_t(u32, mdsl, 4 * PAGE_SIZE);
48 	mdsl = min_t(u32, mdsl, (MAX_SKB_FRAGS - 1) * PAGE_SIZE);
49 
50 	cdev->mdsl = mdsl;
51 }
52 
53 static void *cxgbit_uld_add(const struct cxgb4_lld_info *lldi)
54 {
55 	struct cxgbit_device *cdev;
56 
57 	if (is_t4(lldi->adapter_type))
58 		return ERR_PTR(-ENODEV);
59 
60 	cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
61 	if (!cdev)
62 		return ERR_PTR(-ENOMEM);
63 
64 	kref_init(&cdev->kref);
65 	spin_lock_init(&cdev->np_lock);
66 
67 	cdev->lldi = *lldi;
68 
69 	cxgbit_set_mdsl(cdev);
70 
71 	if (cxgbit_ddp_init(cdev) < 0) {
72 		kfree(cdev);
73 		return ERR_PTR(-EINVAL);
74 	}
75 
76 	if (!test_bit(CDEV_DDP_ENABLE, &cdev->flags))
77 		pr_info("cdev %s ddp init failed\n",
78 			pci_name(lldi->pdev));
79 
80 	if (lldi->fw_vers >= 0x10d2b00)
81 		set_bit(CDEV_ISO_ENABLE, &cdev->flags);
82 
83 	spin_lock_init(&cdev->cskq.lock);
84 	INIT_LIST_HEAD(&cdev->cskq.list);
85 
86 	mutex_lock(&cdev_list_lock);
87 	list_add_tail(&cdev->list, &cdev_list_head);
88 	mutex_unlock(&cdev_list_lock);
89 
90 	pr_info("cdev %s added for iSCSI target transport\n",
91 		pci_name(lldi->pdev));
92 
93 	return cdev;
94 }
95 
96 static void cxgbit_close_conn(struct cxgbit_device *cdev)
97 {
98 	struct cxgbit_sock *csk;
99 	struct sk_buff *skb;
100 	bool wakeup_thread = false;
101 
102 	spin_lock_bh(&cdev->cskq.lock);
103 	list_for_each_entry(csk, &cdev->cskq.list, list) {
104 		skb = alloc_skb(0, GFP_ATOMIC);
105 		if (!skb)
106 			continue;
107 
108 		spin_lock_bh(&csk->rxq.lock);
109 		__skb_queue_tail(&csk->rxq, skb);
110 		if (skb_queue_len(&csk->rxq) == 1)
111 			wakeup_thread = true;
112 		spin_unlock_bh(&csk->rxq.lock);
113 
114 		if (wakeup_thread) {
115 			wake_up(&csk->waitq);
116 			wakeup_thread = false;
117 		}
118 	}
119 	spin_unlock_bh(&cdev->cskq.lock);
120 }
121 
122 static void cxgbit_detach_cdev(struct cxgbit_device *cdev)
123 {
124 	bool free_cdev = false;
125 
126 	spin_lock_bh(&cdev->cskq.lock);
127 	if (list_empty(&cdev->cskq.list))
128 		free_cdev = true;
129 	spin_unlock_bh(&cdev->cskq.lock);
130 
131 	if (free_cdev) {
132 		mutex_lock(&cdev_list_lock);
133 		list_del(&cdev->list);
134 		mutex_unlock(&cdev_list_lock);
135 
136 		cxgbit_put_cdev(cdev);
137 	} else {
138 		cxgbit_close_conn(cdev);
139 	}
140 }
141 
142 static int cxgbit_uld_state_change(void *handle, enum cxgb4_state state)
143 {
144 	struct cxgbit_device *cdev = handle;
145 
146 	switch (state) {
147 	case CXGB4_STATE_UP:
148 		set_bit(CDEV_STATE_UP, &cdev->flags);
149 		pr_info("cdev %s state UP.\n", pci_name(cdev->lldi.pdev));
150 		break;
151 	case CXGB4_STATE_START_RECOVERY:
152 		clear_bit(CDEV_STATE_UP, &cdev->flags);
153 		cxgbit_close_conn(cdev);
154 		pr_info("cdev %s state RECOVERY.\n", pci_name(cdev->lldi.pdev));
155 		break;
156 	case CXGB4_STATE_DOWN:
157 		pr_info("cdev %s state DOWN.\n", pci_name(cdev->lldi.pdev));
158 		break;
159 	case CXGB4_STATE_DETACH:
160 		clear_bit(CDEV_STATE_UP, &cdev->flags);
161 		pr_info("cdev %s state DETACH.\n", pci_name(cdev->lldi.pdev));
162 		cxgbit_detach_cdev(cdev);
163 		break;
164 	default:
165 		pr_info("cdev %s unknown state %d.\n",
166 			pci_name(cdev->lldi.pdev), state);
167 		break;
168 	}
169 	return 0;
170 }
171 
172 static void
173 cxgbit_process_ddpvld(struct cxgbit_sock *csk, struct cxgbit_lro_pdu_cb *pdu_cb,
174 		      u32 ddpvld)
175 {
176 
177 	if (ddpvld & (1 << CPL_RX_ISCSI_DDP_STATUS_HCRC_SHIFT)) {
178 		pr_info("tid 0x%x, status 0x%x, hcrc bad.\n", csk->tid, ddpvld);
179 		pdu_cb->flags |= PDUCBF_RX_HCRC_ERR;
180 	}
181 
182 	if (ddpvld & (1 << CPL_RX_ISCSI_DDP_STATUS_DCRC_SHIFT)) {
183 		pr_info("tid 0x%x, status 0x%x, dcrc bad.\n", csk->tid, ddpvld);
184 		pdu_cb->flags |= PDUCBF_RX_DCRC_ERR;
185 	}
186 
187 	if (ddpvld & (1 << CPL_RX_ISCSI_DDP_STATUS_PAD_SHIFT))
188 		pr_info("tid 0x%x, status 0x%x, pad bad.\n", csk->tid, ddpvld);
189 
190 	if ((ddpvld & (1 << CPL_RX_ISCSI_DDP_STATUS_DDP_SHIFT)) &&
191 	    (!(pdu_cb->flags & PDUCBF_RX_DATA))) {
192 		pdu_cb->flags |= PDUCBF_RX_DATA_DDPD;
193 	}
194 }
195 
196 static void
197 cxgbit_lro_add_packet_rsp(struct sk_buff *skb, u8 op, const __be64 *rsp)
198 {
199 	struct cxgbit_lro_cb *lro_cb = cxgbit_skb_lro_cb(skb);
200 	struct cxgbit_lro_pdu_cb *pdu_cb = cxgbit_skb_lro_pdu_cb(skb,
201 						lro_cb->pdu_idx);
202 	struct cpl_rx_iscsi_ddp *cpl = (struct cpl_rx_iscsi_ddp *)(rsp + 1);
203 
204 	cxgbit_process_ddpvld(lro_cb->csk, pdu_cb, be32_to_cpu(cpl->ddpvld));
205 
206 	pdu_cb->flags |= PDUCBF_RX_STATUS;
207 	pdu_cb->ddigest = ntohl(cpl->ulp_crc);
208 	pdu_cb->pdulen = ntohs(cpl->len);
209 
210 	if (pdu_cb->flags & PDUCBF_RX_HDR)
211 		pdu_cb->complete = true;
212 
213 	lro_cb->pdu_totallen += pdu_cb->pdulen;
214 	lro_cb->complete = true;
215 	lro_cb->pdu_idx++;
216 }
217 
218 static void
219 cxgbit_copy_frags(struct sk_buff *skb, const struct pkt_gl *gl,
220 		  unsigned int offset)
221 {
222 	u8 skb_frag_idx = skb_shinfo(skb)->nr_frags;
223 	u8 i;
224 
225 	/* usually there's just one frag */
226 	__skb_fill_page_desc(skb, skb_frag_idx, gl->frags[0].page,
227 			     gl->frags[0].offset + offset,
228 			     gl->frags[0].size - offset);
229 	for (i = 1; i < gl->nfrags; i++)
230 		__skb_fill_page_desc(skb, skb_frag_idx + i,
231 				     gl->frags[i].page,
232 				     gl->frags[i].offset,
233 				     gl->frags[i].size);
234 
235 	skb_shinfo(skb)->nr_frags += gl->nfrags;
236 
237 	/* get a reference to the last page, we don't own it */
238 	get_page(gl->frags[gl->nfrags - 1].page);
239 }
240 
241 static void
242 cxgbit_lro_add_packet_gl(struct sk_buff *skb, u8 op, const struct pkt_gl *gl)
243 {
244 	struct cxgbit_lro_cb *lro_cb = cxgbit_skb_lro_cb(skb);
245 	struct cxgbit_lro_pdu_cb *pdu_cb = cxgbit_skb_lro_pdu_cb(skb,
246 						lro_cb->pdu_idx);
247 	u32 len, offset;
248 
249 	if (op == CPL_ISCSI_HDR) {
250 		struct cpl_iscsi_hdr *cpl = (struct cpl_iscsi_hdr *)gl->va;
251 
252 		offset = sizeof(struct cpl_iscsi_hdr);
253 		pdu_cb->flags |= PDUCBF_RX_HDR;
254 		pdu_cb->seq = ntohl(cpl->seq);
255 		len = ntohs(cpl->len);
256 		pdu_cb->hdr = gl->va + offset;
257 		pdu_cb->hlen = len;
258 		pdu_cb->hfrag_idx = skb_shinfo(skb)->nr_frags;
259 
260 		if (unlikely(gl->nfrags > 1))
261 			cxgbit_skcb_flags(skb) = 0;
262 
263 		lro_cb->complete = false;
264 	} else if (op == CPL_ISCSI_DATA) {
265 		struct cpl_iscsi_data *cpl = (struct cpl_iscsi_data *)gl->va;
266 
267 		offset = sizeof(struct cpl_iscsi_data);
268 		pdu_cb->flags |= PDUCBF_RX_DATA;
269 		len = ntohs(cpl->len);
270 		pdu_cb->dlen = len;
271 		pdu_cb->doffset = lro_cb->offset;
272 		pdu_cb->nr_dfrags = gl->nfrags;
273 		pdu_cb->dfrag_idx = skb_shinfo(skb)->nr_frags;
274 		lro_cb->complete = false;
275 	} else {
276 		struct cpl_rx_iscsi_cmp *cpl;
277 
278 		cpl = (struct cpl_rx_iscsi_cmp *)gl->va;
279 		offset = sizeof(struct cpl_rx_iscsi_cmp);
280 		pdu_cb->flags |= (PDUCBF_RX_HDR | PDUCBF_RX_STATUS);
281 		len = be16_to_cpu(cpl->len);
282 		pdu_cb->hdr = gl->va + offset;
283 		pdu_cb->hlen = len;
284 		pdu_cb->hfrag_idx = skb_shinfo(skb)->nr_frags;
285 		pdu_cb->ddigest = be32_to_cpu(cpl->ulp_crc);
286 		pdu_cb->pdulen = ntohs(cpl->len);
287 
288 		if (unlikely(gl->nfrags > 1))
289 			cxgbit_skcb_flags(skb) = 0;
290 
291 		cxgbit_process_ddpvld(lro_cb->csk, pdu_cb,
292 				      be32_to_cpu(cpl->ddpvld));
293 
294 		if (pdu_cb->flags & PDUCBF_RX_DATA_DDPD) {
295 			pdu_cb->flags |= PDUCBF_RX_DDP_CMP;
296 			pdu_cb->complete = true;
297 		} else if (pdu_cb->flags & PDUCBF_RX_DATA) {
298 			pdu_cb->complete = true;
299 		}
300 
301 		lro_cb->pdu_totallen += pdu_cb->hlen + pdu_cb->dlen;
302 		lro_cb->complete = true;
303 		lro_cb->pdu_idx++;
304 	}
305 
306 	cxgbit_copy_frags(skb, gl, offset);
307 
308 	pdu_cb->frags += gl->nfrags;
309 	lro_cb->offset += len;
310 	skb->len += len;
311 	skb->data_len += len;
312 	skb->truesize += len;
313 }
314 
315 static struct sk_buff *
316 cxgbit_lro_init_skb(struct cxgbit_sock *csk, u8 op, const struct pkt_gl *gl,
317 		    const __be64 *rsp, struct napi_struct *napi)
318 {
319 	struct sk_buff *skb;
320 	struct cxgbit_lro_cb *lro_cb;
321 
322 	skb = napi_alloc_skb(napi, LRO_SKB_MAX_HEADROOM);
323 
324 	if (unlikely(!skb))
325 		return NULL;
326 
327 	memset(skb->data, 0, LRO_SKB_MAX_HEADROOM);
328 
329 	cxgbit_skcb_flags(skb) |= SKCBF_RX_LRO;
330 
331 	lro_cb = cxgbit_skb_lro_cb(skb);
332 
333 	cxgbit_get_csk(csk);
334 
335 	lro_cb->csk = csk;
336 
337 	return skb;
338 }
339 
340 static void cxgbit_queue_lro_skb(struct cxgbit_sock *csk, struct sk_buff *skb)
341 {
342 	bool wakeup_thread = false;
343 
344 	spin_lock(&csk->rxq.lock);
345 	__skb_queue_tail(&csk->rxq, skb);
346 	if (skb_queue_len(&csk->rxq) == 1)
347 		wakeup_thread = true;
348 	spin_unlock(&csk->rxq.lock);
349 
350 	if (wakeup_thread)
351 		wake_up(&csk->waitq);
352 }
353 
354 static void cxgbit_lro_flush(struct t4_lro_mgr *lro_mgr, struct sk_buff *skb)
355 {
356 	struct cxgbit_lro_cb *lro_cb = cxgbit_skb_lro_cb(skb);
357 	struct cxgbit_sock *csk = lro_cb->csk;
358 
359 	csk->lro_skb = NULL;
360 
361 	__skb_unlink(skb, &lro_mgr->lroq);
362 	cxgbit_queue_lro_skb(csk, skb);
363 
364 	cxgbit_put_csk(csk);
365 
366 	lro_mgr->lro_pkts++;
367 	lro_mgr->lro_session_cnt--;
368 }
369 
370 static void cxgbit_uld_lro_flush(struct t4_lro_mgr *lro_mgr)
371 {
372 	struct sk_buff *skb;
373 
374 	while ((skb = skb_peek(&lro_mgr->lroq)))
375 		cxgbit_lro_flush(lro_mgr, skb);
376 }
377 
378 static int
379 cxgbit_lro_receive(struct cxgbit_sock *csk, u8 op, const __be64 *rsp,
380 		   const struct pkt_gl *gl, struct t4_lro_mgr *lro_mgr,
381 		   struct napi_struct *napi)
382 {
383 	struct sk_buff *skb;
384 	struct cxgbit_lro_cb *lro_cb;
385 
386 	if (!csk) {
387 		pr_err("%s: csk NULL, op 0x%x.\n", __func__, op);
388 		goto out;
389 	}
390 
391 	if (csk->lro_skb)
392 		goto add_packet;
393 
394 start_lro:
395 	if (lro_mgr->lro_session_cnt >= MAX_LRO_SESSIONS) {
396 		cxgbit_uld_lro_flush(lro_mgr);
397 		goto start_lro;
398 	}
399 
400 	skb = cxgbit_lro_init_skb(csk, op, gl, rsp, napi);
401 	if (unlikely(!skb))
402 		goto out;
403 
404 	csk->lro_skb = skb;
405 
406 	__skb_queue_tail(&lro_mgr->lroq, skb);
407 	lro_mgr->lro_session_cnt++;
408 
409 add_packet:
410 	skb = csk->lro_skb;
411 	lro_cb = cxgbit_skb_lro_cb(skb);
412 
413 	if ((gl && (((skb_shinfo(skb)->nr_frags + gl->nfrags) >
414 	    MAX_SKB_FRAGS) || (lro_cb->pdu_totallen >= LRO_FLUSH_LEN_MAX))) ||
415 	    (lro_cb->pdu_idx >= MAX_SKB_FRAGS)) {
416 		cxgbit_lro_flush(lro_mgr, skb);
417 		goto start_lro;
418 	}
419 
420 	if (gl)
421 		cxgbit_lro_add_packet_gl(skb, op, gl);
422 	else
423 		cxgbit_lro_add_packet_rsp(skb, op, rsp);
424 
425 	lro_mgr->lro_merged++;
426 
427 	return 0;
428 
429 out:
430 	return -1;
431 }
432 
433 static int
434 cxgbit_uld_lro_rx_handler(void *hndl, const __be64 *rsp,
435 			  const struct pkt_gl *gl, struct t4_lro_mgr *lro_mgr,
436 			  struct napi_struct *napi)
437 {
438 	struct cxgbit_device *cdev = hndl;
439 	struct cxgb4_lld_info *lldi = &cdev->lldi;
440 	struct cpl_tx_data *rpl = NULL;
441 	struct cxgbit_sock *csk = NULL;
442 	unsigned int tid = 0;
443 	struct sk_buff *skb;
444 	unsigned int op = *(u8 *)rsp;
445 	bool lro_flush = true;
446 
447 	switch (op) {
448 	case CPL_ISCSI_HDR:
449 	case CPL_ISCSI_DATA:
450 	case CPL_RX_ISCSI_CMP:
451 	case CPL_RX_ISCSI_DDP:
452 	case CPL_FW4_ACK:
453 		lro_flush = false;
454 		fallthrough;
455 	case CPL_ABORT_RPL_RSS:
456 	case CPL_PASS_ESTABLISH:
457 	case CPL_PEER_CLOSE:
458 	case CPL_CLOSE_CON_RPL:
459 	case CPL_ABORT_REQ_RSS:
460 	case CPL_SET_TCB_RPL:
461 	case CPL_RX_DATA:
462 		rpl = gl ? (struct cpl_tx_data *)gl->va :
463 			   (struct cpl_tx_data *)(rsp + 1);
464 		tid = GET_TID(rpl);
465 		csk = lookup_tid(lldi->tids, tid);
466 		break;
467 	default:
468 		break;
469 	}
470 
471 	if (csk && csk->lro_skb && lro_flush)
472 		cxgbit_lro_flush(lro_mgr, csk->lro_skb);
473 
474 	if (!gl) {
475 		unsigned int len;
476 
477 		if (op == CPL_RX_ISCSI_DDP) {
478 			if (!cxgbit_lro_receive(csk, op, rsp, NULL, lro_mgr,
479 						napi))
480 				return 0;
481 		}
482 
483 		len = 64 - sizeof(struct rsp_ctrl) - 8;
484 		skb = napi_alloc_skb(napi, len);
485 		if (!skb)
486 			goto nomem;
487 		__skb_put(skb, len);
488 		skb_copy_to_linear_data(skb, &rsp[1], len);
489 	} else {
490 		if (unlikely(op != *(u8 *)gl->va)) {
491 			pr_info("? FL 0x%p,RSS%#llx,FL %#llx,len %u.\n",
492 				gl->va, be64_to_cpu(*rsp),
493 				get_unaligned_be64(gl->va),
494 				gl->tot_len);
495 			return 0;
496 		}
497 
498 		if ((op == CPL_ISCSI_HDR) || (op == CPL_ISCSI_DATA) ||
499 		    (op == CPL_RX_ISCSI_CMP)) {
500 			if (!cxgbit_lro_receive(csk, op, rsp, gl, lro_mgr,
501 						napi))
502 				return 0;
503 		}
504 
505 #define RX_PULL_LEN 128
506 		skb = cxgb4_pktgl_to_skb(gl, RX_PULL_LEN, RX_PULL_LEN);
507 		if (unlikely(!skb))
508 			goto nomem;
509 	}
510 
511 	rpl = (struct cpl_tx_data *)skb->data;
512 	op = rpl->ot.opcode;
513 	cxgbit_skcb_rx_opcode(skb) = op;
514 
515 	pr_debug("cdev %p, opcode 0x%x(0x%x,0x%x), skb %p.\n",
516 		 cdev, op, rpl->ot.opcode_tid,
517 		 ntohl(rpl->ot.opcode_tid), skb);
518 
519 	if (op < NUM_CPL_CMDS && cxgbit_cplhandlers[op]) {
520 		cxgbit_cplhandlers[op](cdev, skb);
521 	} else {
522 		pr_err("No handler for opcode 0x%x.\n", op);
523 		__kfree_skb(skb);
524 	}
525 	return 0;
526 nomem:
527 	pr_err("%s OOM bailing out.\n", __func__);
528 	return 1;
529 }
530 
531 #ifdef CONFIG_CHELSIO_T4_DCB
532 struct cxgbit_dcb_work {
533 	struct dcb_app_type dcb_app;
534 	struct work_struct work;
535 };
536 
537 static void
538 cxgbit_update_dcb_priority(struct cxgbit_device *cdev, u8 port_id,
539 			   u8 dcb_priority, u16 port_num)
540 {
541 	struct cxgbit_sock *csk;
542 	struct sk_buff *skb;
543 	u16 local_port;
544 	bool wakeup_thread = false;
545 
546 	spin_lock_bh(&cdev->cskq.lock);
547 	list_for_each_entry(csk, &cdev->cskq.list, list) {
548 		if (csk->port_id != port_id)
549 			continue;
550 
551 		if (csk->com.local_addr.ss_family == AF_INET6) {
552 			struct sockaddr_in6 *sock_in6;
553 
554 			sock_in6 = (struct sockaddr_in6 *)&csk->com.local_addr;
555 			local_port = ntohs(sock_in6->sin6_port);
556 		} else {
557 			struct sockaddr_in *sock_in;
558 
559 			sock_in = (struct sockaddr_in *)&csk->com.local_addr;
560 			local_port = ntohs(sock_in->sin_port);
561 		}
562 
563 		if (local_port != port_num)
564 			continue;
565 
566 		if (csk->dcb_priority == dcb_priority)
567 			continue;
568 
569 		skb = alloc_skb(0, GFP_ATOMIC);
570 		if (!skb)
571 			continue;
572 
573 		spin_lock(&csk->rxq.lock);
574 		__skb_queue_tail(&csk->rxq, skb);
575 		if (skb_queue_len(&csk->rxq) == 1)
576 			wakeup_thread = true;
577 		spin_unlock(&csk->rxq.lock);
578 
579 		if (wakeup_thread) {
580 			wake_up(&csk->waitq);
581 			wakeup_thread = false;
582 		}
583 	}
584 	spin_unlock_bh(&cdev->cskq.lock);
585 }
586 
587 static void cxgbit_dcb_workfn(struct work_struct *work)
588 {
589 	struct cxgbit_dcb_work *dcb_work;
590 	struct net_device *ndev;
591 	struct cxgbit_device *cdev = NULL;
592 	struct dcb_app_type *iscsi_app;
593 	u8 priority, port_id = 0xff;
594 
595 	dcb_work = container_of(work, struct cxgbit_dcb_work, work);
596 	iscsi_app = &dcb_work->dcb_app;
597 
598 	if (iscsi_app->dcbx & DCB_CAP_DCBX_VER_IEEE) {
599 		if ((iscsi_app->app.selector != IEEE_8021QAZ_APP_SEL_STREAM) &&
600 		    (iscsi_app->app.selector != IEEE_8021QAZ_APP_SEL_ANY))
601 			goto out;
602 
603 		priority = iscsi_app->app.priority;
604 
605 	} else if (iscsi_app->dcbx & DCB_CAP_DCBX_VER_CEE) {
606 		if (iscsi_app->app.selector != DCB_APP_IDTYPE_PORTNUM)
607 			goto out;
608 
609 		if (!iscsi_app->app.priority)
610 			goto out;
611 
612 		priority = ffs(iscsi_app->app.priority) - 1;
613 	} else {
614 		goto out;
615 	}
616 
617 	pr_debug("priority for ifid %d is %u\n",
618 		 iscsi_app->ifindex, priority);
619 
620 	ndev = dev_get_by_index(&init_net, iscsi_app->ifindex);
621 
622 	if (!ndev)
623 		goto out;
624 
625 	mutex_lock(&cdev_list_lock);
626 	cdev = cxgbit_find_device(ndev, &port_id);
627 
628 	dev_put(ndev);
629 
630 	if (!cdev) {
631 		mutex_unlock(&cdev_list_lock);
632 		goto out;
633 	}
634 
635 	cxgbit_update_dcb_priority(cdev, port_id, priority,
636 				   iscsi_app->app.protocol);
637 	mutex_unlock(&cdev_list_lock);
638 out:
639 	kfree(dcb_work);
640 }
641 
642 static int
643 cxgbit_dcbevent_notify(struct notifier_block *nb, unsigned long action,
644 		       void *data)
645 {
646 	struct cxgbit_dcb_work *dcb_work;
647 	struct dcb_app_type *dcb_app = data;
648 
649 	dcb_work = kzalloc(sizeof(*dcb_work), GFP_ATOMIC);
650 	if (!dcb_work)
651 		return NOTIFY_DONE;
652 
653 	dcb_work->dcb_app = *dcb_app;
654 	INIT_WORK(&dcb_work->work, cxgbit_dcb_workfn);
655 	schedule_work(&dcb_work->work);
656 	return NOTIFY_OK;
657 }
658 #endif
659 
660 static enum target_prot_op cxgbit_get_sup_prot_ops(struct iscsit_conn *conn)
661 {
662 	return TARGET_PROT_NORMAL;
663 }
664 
665 static struct iscsit_transport cxgbit_transport = {
666 	.name			= DRV_NAME,
667 	.transport_type		= ISCSI_CXGBIT,
668 	.rdma_shutdown		= false,
669 	.priv_size		= sizeof(struct cxgbit_cmd),
670 	.owner			= THIS_MODULE,
671 	.iscsit_setup_np	= cxgbit_setup_np,
672 	.iscsit_accept_np	= cxgbit_accept_np,
673 	.iscsit_free_np		= cxgbit_free_np,
674 	.iscsit_free_conn	= cxgbit_free_conn,
675 	.iscsit_get_login_rx	= cxgbit_get_login_rx,
676 	.iscsit_put_login_tx	= cxgbit_put_login_tx,
677 	.iscsit_immediate_queue	= iscsit_immediate_queue,
678 	.iscsit_response_queue	= iscsit_response_queue,
679 	.iscsit_get_dataout	= iscsit_build_r2ts_for_cmd,
680 	.iscsit_queue_data_in	= iscsit_queue_rsp,
681 	.iscsit_queue_status	= iscsit_queue_rsp,
682 	.iscsit_xmit_pdu	= cxgbit_xmit_pdu,
683 	.iscsit_get_r2t_ttt	= cxgbit_get_r2t_ttt,
684 	.iscsit_get_rx_pdu	= cxgbit_get_rx_pdu,
685 	.iscsit_validate_params	= cxgbit_validate_params,
686 	.iscsit_unmap_cmd	= cxgbit_unmap_cmd,
687 	.iscsit_aborted_task	= iscsit_aborted_task,
688 	.iscsit_get_sup_prot_ops = cxgbit_get_sup_prot_ops,
689 };
690 
691 static struct cxgb4_uld_info cxgbit_uld_info = {
692 	.name		= DRV_NAME,
693 	.nrxq		= MAX_ULD_QSETS,
694 	.ntxq		= MAX_ULD_QSETS,
695 	.rxq_size	= 1024,
696 	.lro		= true,
697 	.add		= cxgbit_uld_add,
698 	.state_change	= cxgbit_uld_state_change,
699 	.lro_rx_handler = cxgbit_uld_lro_rx_handler,
700 	.lro_flush	= cxgbit_uld_lro_flush,
701 };
702 
703 #ifdef CONFIG_CHELSIO_T4_DCB
704 static struct notifier_block cxgbit_dcbevent_nb = {
705 	.notifier_call = cxgbit_dcbevent_notify,
706 };
707 #endif
708 
709 static int __init cxgbit_init(void)
710 {
711 	cxgb4_register_uld(CXGB4_ULD_ISCSIT, &cxgbit_uld_info);
712 	iscsit_register_transport(&cxgbit_transport);
713 
714 #ifdef CONFIG_CHELSIO_T4_DCB
715 	pr_info("%s dcb enabled.\n", DRV_NAME);
716 	register_dcbevent_notifier(&cxgbit_dcbevent_nb);
717 #endif
718 	BUILD_BUG_ON(sizeof_field(struct sk_buff, cb) <
719 		     sizeof(union cxgbit_skb_cb));
720 	return 0;
721 }
722 
723 static void __exit cxgbit_exit(void)
724 {
725 	struct cxgbit_device *cdev, *tmp;
726 
727 #ifdef CONFIG_CHELSIO_T4_DCB
728 	unregister_dcbevent_notifier(&cxgbit_dcbevent_nb);
729 #endif
730 	mutex_lock(&cdev_list_lock);
731 	list_for_each_entry_safe(cdev, tmp, &cdev_list_head, list) {
732 		list_del(&cdev->list);
733 		cxgbit_put_cdev(cdev);
734 	}
735 	mutex_unlock(&cdev_list_lock);
736 	iscsit_unregister_transport(&cxgbit_transport);
737 	cxgb4_unregister_uld(CXGB4_ULD_ISCSIT);
738 }
739 
740 module_init(cxgbit_init);
741 module_exit(cxgbit_exit);
742 
743 MODULE_DESCRIPTION("Chelsio iSCSI target offload driver");
744 MODULE_AUTHOR("Chelsio Communications");
745 MODULE_VERSION(DRV_VERSION);
746 MODULE_LICENSE("GPL");
747