xref: /linux/drivers/target/iscsi/cxgbit/cxgbit_main.c (revision f474808acb3c4b30552d9c59b181244e0300d218)
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 ULP2_MAX_PKT_LEN 16224
37 #define ISCSI_PDU_NONPAYLOAD_LEN 312
38 	mdsl = min_t(u32, lldi->iscsi_iolen - ISCSI_PDU_NONPAYLOAD_LEN,
39 		     ULP2_MAX_PKT_LEN - ISCSI_PDU_NONPAYLOAD_LEN);
40 	mdsl = min_t(u32, mdsl, 8192);
41 	mdsl = min_t(u32, mdsl, (MAX_SKB_FRAGS - 1) * PAGE_SIZE);
42 
43 	cdev->mdsl = mdsl;
44 }
45 
46 static void *cxgbit_uld_add(const struct cxgb4_lld_info *lldi)
47 {
48 	struct cxgbit_device *cdev;
49 
50 	if (is_t4(lldi->adapter_type))
51 		return ERR_PTR(-ENODEV);
52 
53 	cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
54 	if (!cdev)
55 		return ERR_PTR(-ENOMEM);
56 
57 	kref_init(&cdev->kref);
58 	spin_lock_init(&cdev->np_lock);
59 
60 	cdev->lldi = *lldi;
61 
62 	cxgbit_set_mdsl(cdev);
63 
64 	if (cxgbit_ddp_init(cdev) < 0) {
65 		kfree(cdev);
66 		return ERR_PTR(-EINVAL);
67 	}
68 
69 	if (!test_bit(CDEV_DDP_ENABLE, &cdev->flags))
70 		pr_info("cdev %s ddp init failed\n",
71 			pci_name(lldi->pdev));
72 
73 	if (lldi->fw_vers >= 0x10d2b00)
74 		set_bit(CDEV_ISO_ENABLE, &cdev->flags);
75 
76 	spin_lock_init(&cdev->cskq.lock);
77 	INIT_LIST_HEAD(&cdev->cskq.list);
78 
79 	mutex_lock(&cdev_list_lock);
80 	list_add_tail(&cdev->list, &cdev_list_head);
81 	mutex_unlock(&cdev_list_lock);
82 
83 	pr_info("cdev %s added for iSCSI target transport\n",
84 		pci_name(lldi->pdev));
85 
86 	return cdev;
87 }
88 
89 static void cxgbit_close_conn(struct cxgbit_device *cdev)
90 {
91 	struct cxgbit_sock *csk;
92 	struct sk_buff *skb;
93 	bool wakeup_thread = false;
94 
95 	spin_lock_bh(&cdev->cskq.lock);
96 	list_for_each_entry(csk, &cdev->cskq.list, list) {
97 		skb = alloc_skb(0, GFP_ATOMIC);
98 		if (!skb)
99 			continue;
100 
101 		spin_lock_bh(&csk->rxq.lock);
102 		__skb_queue_tail(&csk->rxq, skb);
103 		if (skb_queue_len(&csk->rxq) == 1)
104 			wakeup_thread = true;
105 		spin_unlock_bh(&csk->rxq.lock);
106 
107 		if (wakeup_thread) {
108 			wake_up(&csk->waitq);
109 			wakeup_thread = false;
110 		}
111 	}
112 	spin_unlock_bh(&cdev->cskq.lock);
113 }
114 
115 static void cxgbit_detach_cdev(struct cxgbit_device *cdev)
116 {
117 	bool free_cdev = false;
118 
119 	spin_lock_bh(&cdev->cskq.lock);
120 	if (list_empty(&cdev->cskq.list))
121 		free_cdev = true;
122 	spin_unlock_bh(&cdev->cskq.lock);
123 
124 	if (free_cdev) {
125 		mutex_lock(&cdev_list_lock);
126 		list_del(&cdev->list);
127 		mutex_unlock(&cdev_list_lock);
128 
129 		cxgbit_put_cdev(cdev);
130 	} else {
131 		cxgbit_close_conn(cdev);
132 	}
133 }
134 
135 static int cxgbit_uld_state_change(void *handle, enum cxgb4_state state)
136 {
137 	struct cxgbit_device *cdev = handle;
138 
139 	switch (state) {
140 	case CXGB4_STATE_UP:
141 		set_bit(CDEV_STATE_UP, &cdev->flags);
142 		pr_info("cdev %s state UP.\n", pci_name(cdev->lldi.pdev));
143 		break;
144 	case CXGB4_STATE_START_RECOVERY:
145 		clear_bit(CDEV_STATE_UP, &cdev->flags);
146 		cxgbit_close_conn(cdev);
147 		pr_info("cdev %s state RECOVERY.\n", pci_name(cdev->lldi.pdev));
148 		break;
149 	case CXGB4_STATE_DOWN:
150 		pr_info("cdev %s state DOWN.\n", pci_name(cdev->lldi.pdev));
151 		break;
152 	case CXGB4_STATE_DETACH:
153 		clear_bit(CDEV_STATE_UP, &cdev->flags);
154 		pr_info("cdev %s state DETACH.\n", pci_name(cdev->lldi.pdev));
155 		cxgbit_detach_cdev(cdev);
156 		break;
157 	default:
158 		pr_info("cdev %s unknown state %d.\n",
159 			pci_name(cdev->lldi.pdev), state);
160 		break;
161 	}
162 	return 0;
163 }
164 
165 static void
166 cxgbit_process_ddpvld(struct cxgbit_sock *csk, struct cxgbit_lro_pdu_cb *pdu_cb,
167 		      u32 ddpvld)
168 {
169 
170 	if (ddpvld & (1 << CPL_RX_ISCSI_DDP_STATUS_HCRC_SHIFT)) {
171 		pr_info("tid 0x%x, status 0x%x, hcrc bad.\n", csk->tid, ddpvld);
172 		pdu_cb->flags |= PDUCBF_RX_HCRC_ERR;
173 	}
174 
175 	if (ddpvld & (1 << CPL_RX_ISCSI_DDP_STATUS_DCRC_SHIFT)) {
176 		pr_info("tid 0x%x, status 0x%x, dcrc bad.\n", csk->tid, ddpvld);
177 		pdu_cb->flags |= PDUCBF_RX_DCRC_ERR;
178 	}
179 
180 	if (ddpvld & (1 << CPL_RX_ISCSI_DDP_STATUS_PAD_SHIFT))
181 		pr_info("tid 0x%x, status 0x%x, pad bad.\n", csk->tid, ddpvld);
182 
183 	if ((ddpvld & (1 << CPL_RX_ISCSI_DDP_STATUS_DDP_SHIFT)) &&
184 	    (!(pdu_cb->flags & PDUCBF_RX_DATA))) {
185 		pdu_cb->flags |= PDUCBF_RX_DATA_DDPD;
186 	}
187 }
188 
189 static void
190 cxgbit_lro_add_packet_rsp(struct sk_buff *skb, u8 op, const __be64 *rsp)
191 {
192 	struct cxgbit_lro_cb *lro_cb = cxgbit_skb_lro_cb(skb);
193 	struct cxgbit_lro_pdu_cb *pdu_cb = cxgbit_skb_lro_pdu_cb(skb,
194 						lro_cb->pdu_idx);
195 	struct cpl_rx_iscsi_ddp *cpl = (struct cpl_rx_iscsi_ddp *)(rsp + 1);
196 
197 	cxgbit_process_ddpvld(lro_cb->csk, pdu_cb, be32_to_cpu(cpl->ddpvld));
198 
199 	pdu_cb->flags |= PDUCBF_RX_STATUS;
200 	pdu_cb->ddigest = ntohl(cpl->ulp_crc);
201 	pdu_cb->pdulen = ntohs(cpl->len);
202 
203 	if (pdu_cb->flags & PDUCBF_RX_HDR)
204 		pdu_cb->complete = true;
205 
206 	lro_cb->pdu_totallen += pdu_cb->pdulen;
207 	lro_cb->complete = true;
208 	lro_cb->pdu_idx++;
209 }
210 
211 static void
212 cxgbit_copy_frags(struct sk_buff *skb, const struct pkt_gl *gl,
213 		  unsigned int offset)
214 {
215 	u8 skb_frag_idx = skb_shinfo(skb)->nr_frags;
216 	u8 i;
217 
218 	/* usually there's just one frag */
219 	__skb_fill_page_desc(skb, skb_frag_idx, gl->frags[0].page,
220 			     gl->frags[0].offset + offset,
221 			     gl->frags[0].size - offset);
222 	for (i = 1; i < gl->nfrags; i++)
223 		__skb_fill_page_desc(skb, skb_frag_idx + i,
224 				     gl->frags[i].page,
225 				     gl->frags[i].offset,
226 				     gl->frags[i].size);
227 
228 	skb_shinfo(skb)->nr_frags += gl->nfrags;
229 
230 	/* get a reference to the last page, we don't own it */
231 	get_page(gl->frags[gl->nfrags - 1].page);
232 }
233 
234 static void
235 cxgbit_lro_add_packet_gl(struct sk_buff *skb, u8 op, const struct pkt_gl *gl)
236 {
237 	struct cxgbit_lro_cb *lro_cb = cxgbit_skb_lro_cb(skb);
238 	struct cxgbit_lro_pdu_cb *pdu_cb = cxgbit_skb_lro_pdu_cb(skb,
239 						lro_cb->pdu_idx);
240 	u32 len, offset;
241 
242 	if (op == CPL_ISCSI_HDR) {
243 		struct cpl_iscsi_hdr *cpl = (struct cpl_iscsi_hdr *)gl->va;
244 
245 		offset = sizeof(struct cpl_iscsi_hdr);
246 		pdu_cb->flags |= PDUCBF_RX_HDR;
247 		pdu_cb->seq = ntohl(cpl->seq);
248 		len = ntohs(cpl->len);
249 		pdu_cb->hdr = gl->va + offset;
250 		pdu_cb->hlen = len;
251 		pdu_cb->hfrag_idx = skb_shinfo(skb)->nr_frags;
252 
253 		if (unlikely(gl->nfrags > 1))
254 			cxgbit_skcb_flags(skb) = 0;
255 
256 		lro_cb->complete = false;
257 	} else if (op == CPL_ISCSI_DATA) {
258 		struct cpl_iscsi_data *cpl = (struct cpl_iscsi_data *)gl->va;
259 
260 		offset = sizeof(struct cpl_iscsi_data);
261 		pdu_cb->flags |= PDUCBF_RX_DATA;
262 		len = ntohs(cpl->len);
263 		pdu_cb->dlen = len;
264 		pdu_cb->doffset = lro_cb->offset;
265 		pdu_cb->nr_dfrags = gl->nfrags;
266 		pdu_cb->dfrag_idx = skb_shinfo(skb)->nr_frags;
267 		lro_cb->complete = false;
268 	} else {
269 		struct cpl_rx_iscsi_cmp *cpl;
270 
271 		cpl = (struct cpl_rx_iscsi_cmp *)gl->va;
272 		offset = sizeof(struct cpl_rx_iscsi_cmp);
273 		pdu_cb->flags |= (PDUCBF_RX_HDR | PDUCBF_RX_STATUS);
274 		len = be16_to_cpu(cpl->len);
275 		pdu_cb->hdr = gl->va + offset;
276 		pdu_cb->hlen = len;
277 		pdu_cb->hfrag_idx = skb_shinfo(skb)->nr_frags;
278 		pdu_cb->ddigest = be32_to_cpu(cpl->ulp_crc);
279 		pdu_cb->pdulen = ntohs(cpl->len);
280 
281 		if (unlikely(gl->nfrags > 1))
282 			cxgbit_skcb_flags(skb) = 0;
283 
284 		cxgbit_process_ddpvld(lro_cb->csk, pdu_cb,
285 				      be32_to_cpu(cpl->ddpvld));
286 
287 		if (pdu_cb->flags & PDUCBF_RX_DATA_DDPD) {
288 			pdu_cb->flags |= PDUCBF_RX_DDP_CMP;
289 			pdu_cb->complete = true;
290 		} else if (pdu_cb->flags & PDUCBF_RX_DATA) {
291 			pdu_cb->complete = true;
292 		}
293 
294 		lro_cb->pdu_totallen += pdu_cb->hlen + pdu_cb->dlen;
295 		lro_cb->complete = true;
296 		lro_cb->pdu_idx++;
297 	}
298 
299 	cxgbit_copy_frags(skb, gl, offset);
300 
301 	pdu_cb->frags += gl->nfrags;
302 	lro_cb->offset += len;
303 	skb->len += len;
304 	skb->data_len += len;
305 	skb->truesize += len;
306 }
307 
308 static struct sk_buff *
309 cxgbit_lro_init_skb(struct cxgbit_sock *csk, u8 op, const struct pkt_gl *gl,
310 		    const __be64 *rsp, struct napi_struct *napi)
311 {
312 	struct sk_buff *skb;
313 	struct cxgbit_lro_cb *lro_cb;
314 
315 	skb = napi_alloc_skb(napi, LRO_SKB_MAX_HEADROOM);
316 
317 	if (unlikely(!skb))
318 		return NULL;
319 
320 	memset(skb->data, 0, LRO_SKB_MAX_HEADROOM);
321 
322 	cxgbit_skcb_flags(skb) |= SKCBF_RX_LRO;
323 
324 	lro_cb = cxgbit_skb_lro_cb(skb);
325 
326 	cxgbit_get_csk(csk);
327 
328 	lro_cb->csk = csk;
329 
330 	return skb;
331 }
332 
333 static void cxgbit_queue_lro_skb(struct cxgbit_sock *csk, struct sk_buff *skb)
334 {
335 	bool wakeup_thread = false;
336 
337 	spin_lock(&csk->rxq.lock);
338 	__skb_queue_tail(&csk->rxq, skb);
339 	if (skb_queue_len(&csk->rxq) == 1)
340 		wakeup_thread = true;
341 	spin_unlock(&csk->rxq.lock);
342 
343 	if (wakeup_thread)
344 		wake_up(&csk->waitq);
345 }
346 
347 static void cxgbit_lro_flush(struct t4_lro_mgr *lro_mgr, struct sk_buff *skb)
348 {
349 	struct cxgbit_lro_cb *lro_cb = cxgbit_skb_lro_cb(skb);
350 	struct cxgbit_sock *csk = lro_cb->csk;
351 
352 	csk->lro_skb = NULL;
353 
354 	__skb_unlink(skb, &lro_mgr->lroq);
355 	cxgbit_queue_lro_skb(csk, skb);
356 
357 	cxgbit_put_csk(csk);
358 
359 	lro_mgr->lro_pkts++;
360 	lro_mgr->lro_session_cnt--;
361 }
362 
363 static void cxgbit_uld_lro_flush(struct t4_lro_mgr *lro_mgr)
364 {
365 	struct sk_buff *skb;
366 
367 	while ((skb = skb_peek(&lro_mgr->lroq)))
368 		cxgbit_lro_flush(lro_mgr, skb);
369 }
370 
371 static int
372 cxgbit_lro_receive(struct cxgbit_sock *csk, u8 op, const __be64 *rsp,
373 		   const struct pkt_gl *gl, struct t4_lro_mgr *lro_mgr,
374 		   struct napi_struct *napi)
375 {
376 	struct sk_buff *skb;
377 	struct cxgbit_lro_cb *lro_cb;
378 
379 	if (!csk) {
380 		pr_err("%s: csk NULL, op 0x%x.\n", __func__, op);
381 		goto out;
382 	}
383 
384 	if (csk->lro_skb)
385 		goto add_packet;
386 
387 start_lro:
388 	if (lro_mgr->lro_session_cnt >= MAX_LRO_SESSIONS) {
389 		cxgbit_uld_lro_flush(lro_mgr);
390 		goto start_lro;
391 	}
392 
393 	skb = cxgbit_lro_init_skb(csk, op, gl, rsp, napi);
394 	if (unlikely(!skb))
395 		goto out;
396 
397 	csk->lro_skb = skb;
398 
399 	__skb_queue_tail(&lro_mgr->lroq, skb);
400 	lro_mgr->lro_session_cnt++;
401 
402 add_packet:
403 	skb = csk->lro_skb;
404 	lro_cb = cxgbit_skb_lro_cb(skb);
405 
406 	if ((gl && (((skb_shinfo(skb)->nr_frags + gl->nfrags) >
407 	    MAX_SKB_FRAGS) || (lro_cb->pdu_totallen >= LRO_FLUSH_LEN_MAX))) ||
408 	    (lro_cb->pdu_idx >= MAX_SKB_FRAGS)) {
409 		cxgbit_lro_flush(lro_mgr, skb);
410 		goto start_lro;
411 	}
412 
413 	if (gl)
414 		cxgbit_lro_add_packet_gl(skb, op, gl);
415 	else
416 		cxgbit_lro_add_packet_rsp(skb, op, rsp);
417 
418 	lro_mgr->lro_merged++;
419 
420 	return 0;
421 
422 out:
423 	return -1;
424 }
425 
426 static int
427 cxgbit_uld_lro_rx_handler(void *hndl, const __be64 *rsp,
428 			  const struct pkt_gl *gl, struct t4_lro_mgr *lro_mgr,
429 			  struct napi_struct *napi)
430 {
431 	struct cxgbit_device *cdev = hndl;
432 	struct cxgb4_lld_info *lldi = &cdev->lldi;
433 	struct cpl_tx_data *rpl = NULL;
434 	struct cxgbit_sock *csk = NULL;
435 	unsigned int tid = 0;
436 	struct sk_buff *skb;
437 	unsigned int op = *(u8 *)rsp;
438 	bool lro_flush = true;
439 
440 	switch (op) {
441 	case CPL_ISCSI_HDR:
442 	case CPL_ISCSI_DATA:
443 	case CPL_RX_ISCSI_CMP:
444 	case CPL_RX_ISCSI_DDP:
445 	case CPL_FW4_ACK:
446 		lro_flush = false;
447 		/* fall through */
448 	case CPL_ABORT_RPL_RSS:
449 	case CPL_PASS_ESTABLISH:
450 	case CPL_PEER_CLOSE:
451 	case CPL_CLOSE_CON_RPL:
452 	case CPL_ABORT_REQ_RSS:
453 	case CPL_SET_TCB_RPL:
454 	case CPL_RX_DATA:
455 		rpl = gl ? (struct cpl_tx_data *)gl->va :
456 			   (struct cpl_tx_data *)(rsp + 1);
457 		tid = GET_TID(rpl);
458 		csk = lookup_tid(lldi->tids, tid);
459 		break;
460 	default:
461 		break;
462 	}
463 
464 	if (csk && csk->lro_skb && lro_flush)
465 		cxgbit_lro_flush(lro_mgr, csk->lro_skb);
466 
467 	if (!gl) {
468 		unsigned int len;
469 
470 		if (op == CPL_RX_ISCSI_DDP) {
471 			if (!cxgbit_lro_receive(csk, op, rsp, NULL, lro_mgr,
472 						napi))
473 				return 0;
474 		}
475 
476 		len = 64 - sizeof(struct rsp_ctrl) - 8;
477 		skb = napi_alloc_skb(napi, len);
478 		if (!skb)
479 			goto nomem;
480 		__skb_put(skb, len);
481 		skb_copy_to_linear_data(skb, &rsp[1], len);
482 	} else {
483 		if (unlikely(op != *(u8 *)gl->va)) {
484 			pr_info("? FL 0x%p,RSS%#llx,FL %#llx,len %u.\n",
485 				gl->va, be64_to_cpu(*rsp),
486 				get_unaligned_be64(gl->va),
487 				gl->tot_len);
488 			return 0;
489 		}
490 
491 		if ((op == CPL_ISCSI_HDR) || (op == CPL_ISCSI_DATA) ||
492 		    (op == CPL_RX_ISCSI_CMP)) {
493 			if (!cxgbit_lro_receive(csk, op, rsp, gl, lro_mgr,
494 						napi))
495 				return 0;
496 		}
497 
498 #define RX_PULL_LEN 128
499 		skb = cxgb4_pktgl_to_skb(gl, RX_PULL_LEN, RX_PULL_LEN);
500 		if (unlikely(!skb))
501 			goto nomem;
502 	}
503 
504 	rpl = (struct cpl_tx_data *)skb->data;
505 	op = rpl->ot.opcode;
506 	cxgbit_skcb_rx_opcode(skb) = op;
507 
508 	pr_debug("cdev %p, opcode 0x%x(0x%x,0x%x), skb %p.\n",
509 		 cdev, op, rpl->ot.opcode_tid,
510 		 ntohl(rpl->ot.opcode_tid), skb);
511 
512 	if (op < NUM_CPL_CMDS && cxgbit_cplhandlers[op]) {
513 		cxgbit_cplhandlers[op](cdev, skb);
514 	} else {
515 		pr_err("No handler for opcode 0x%x.\n", op);
516 		__kfree_skb(skb);
517 	}
518 	return 0;
519 nomem:
520 	pr_err("%s OOM bailing out.\n", __func__);
521 	return 1;
522 }
523 
524 #ifdef CONFIG_CHELSIO_T4_DCB
525 struct cxgbit_dcb_work {
526 	struct dcb_app_type dcb_app;
527 	struct work_struct work;
528 };
529 
530 static void
531 cxgbit_update_dcb_priority(struct cxgbit_device *cdev, u8 port_id,
532 			   u8 dcb_priority, u16 port_num)
533 {
534 	struct cxgbit_sock *csk;
535 	struct sk_buff *skb;
536 	u16 local_port;
537 	bool wakeup_thread = false;
538 
539 	spin_lock_bh(&cdev->cskq.lock);
540 	list_for_each_entry(csk, &cdev->cskq.list, list) {
541 		if (csk->port_id != port_id)
542 			continue;
543 
544 		if (csk->com.local_addr.ss_family == AF_INET6) {
545 			struct sockaddr_in6 *sock_in6;
546 
547 			sock_in6 = (struct sockaddr_in6 *)&csk->com.local_addr;
548 			local_port = ntohs(sock_in6->sin6_port);
549 		} else {
550 			struct sockaddr_in *sock_in;
551 
552 			sock_in = (struct sockaddr_in *)&csk->com.local_addr;
553 			local_port = ntohs(sock_in->sin_port);
554 		}
555 
556 		if (local_port != port_num)
557 			continue;
558 
559 		if (csk->dcb_priority == dcb_priority)
560 			continue;
561 
562 		skb = alloc_skb(0, GFP_ATOMIC);
563 		if (!skb)
564 			continue;
565 
566 		spin_lock(&csk->rxq.lock);
567 		__skb_queue_tail(&csk->rxq, skb);
568 		if (skb_queue_len(&csk->rxq) == 1)
569 			wakeup_thread = true;
570 		spin_unlock(&csk->rxq.lock);
571 
572 		if (wakeup_thread) {
573 			wake_up(&csk->waitq);
574 			wakeup_thread = false;
575 		}
576 	}
577 	spin_unlock_bh(&cdev->cskq.lock);
578 }
579 
580 static void cxgbit_dcb_workfn(struct work_struct *work)
581 {
582 	struct cxgbit_dcb_work *dcb_work;
583 	struct net_device *ndev;
584 	struct cxgbit_device *cdev = NULL;
585 	struct dcb_app_type *iscsi_app;
586 	u8 priority, port_id = 0xff;
587 
588 	dcb_work = container_of(work, struct cxgbit_dcb_work, work);
589 	iscsi_app = &dcb_work->dcb_app;
590 
591 	if (iscsi_app->dcbx & DCB_CAP_DCBX_VER_IEEE) {
592 		if (iscsi_app->app.selector != IEEE_8021QAZ_APP_SEL_ANY)
593 			goto out;
594 
595 		priority = iscsi_app->app.priority;
596 
597 	} else if (iscsi_app->dcbx & DCB_CAP_DCBX_VER_CEE) {
598 		if (iscsi_app->app.selector != DCB_APP_IDTYPE_PORTNUM)
599 			goto out;
600 
601 		if (!iscsi_app->app.priority)
602 			goto out;
603 
604 		priority = ffs(iscsi_app->app.priority) - 1;
605 	} else {
606 		goto out;
607 	}
608 
609 	pr_debug("priority for ifid %d is %u\n",
610 		 iscsi_app->ifindex, priority);
611 
612 	ndev = dev_get_by_index(&init_net, iscsi_app->ifindex);
613 
614 	if (!ndev)
615 		goto out;
616 
617 	mutex_lock(&cdev_list_lock);
618 	cdev = cxgbit_find_device(ndev, &port_id);
619 
620 	dev_put(ndev);
621 
622 	if (!cdev) {
623 		mutex_unlock(&cdev_list_lock);
624 		goto out;
625 	}
626 
627 	cxgbit_update_dcb_priority(cdev, port_id, priority,
628 				   iscsi_app->app.protocol);
629 	mutex_unlock(&cdev_list_lock);
630 out:
631 	kfree(dcb_work);
632 }
633 
634 static int
635 cxgbit_dcbevent_notify(struct notifier_block *nb, unsigned long action,
636 		       void *data)
637 {
638 	struct cxgbit_dcb_work *dcb_work;
639 	struct dcb_app_type *dcb_app = data;
640 
641 	dcb_work = kzalloc(sizeof(*dcb_work), GFP_ATOMIC);
642 	if (!dcb_work)
643 		return NOTIFY_DONE;
644 
645 	dcb_work->dcb_app = *dcb_app;
646 	INIT_WORK(&dcb_work->work, cxgbit_dcb_workfn);
647 	schedule_work(&dcb_work->work);
648 	return NOTIFY_OK;
649 }
650 #endif
651 
652 static enum target_prot_op cxgbit_get_sup_prot_ops(struct iscsi_conn *conn)
653 {
654 	return TARGET_PROT_NORMAL;
655 }
656 
657 static struct iscsit_transport cxgbit_transport = {
658 	.name			= DRV_NAME,
659 	.transport_type		= ISCSI_CXGBIT,
660 	.rdma_shutdown		= false,
661 	.priv_size		= sizeof(struct cxgbit_cmd),
662 	.owner			= THIS_MODULE,
663 	.iscsit_setup_np	= cxgbit_setup_np,
664 	.iscsit_accept_np	= cxgbit_accept_np,
665 	.iscsit_free_np		= cxgbit_free_np,
666 	.iscsit_free_conn	= cxgbit_free_conn,
667 	.iscsit_get_login_rx	= cxgbit_get_login_rx,
668 	.iscsit_put_login_tx	= cxgbit_put_login_tx,
669 	.iscsit_immediate_queue	= iscsit_immediate_queue,
670 	.iscsit_response_queue	= iscsit_response_queue,
671 	.iscsit_get_dataout	= iscsit_build_r2ts_for_cmd,
672 	.iscsit_queue_data_in	= iscsit_queue_rsp,
673 	.iscsit_queue_status	= iscsit_queue_rsp,
674 	.iscsit_xmit_pdu	= cxgbit_xmit_pdu,
675 	.iscsit_get_r2t_ttt	= cxgbit_get_r2t_ttt,
676 	.iscsit_get_rx_pdu	= cxgbit_get_rx_pdu,
677 	.iscsit_validate_params	= cxgbit_validate_params,
678 	.iscsit_unmap_cmd	= cxgbit_unmap_cmd,
679 	.iscsit_aborted_task	= iscsit_aborted_task,
680 	.iscsit_get_sup_prot_ops = cxgbit_get_sup_prot_ops,
681 };
682 
683 static struct cxgb4_uld_info cxgbit_uld_info = {
684 	.name		= DRV_NAME,
685 	.nrxq		= MAX_ULD_QSETS,
686 	.ntxq		= MAX_ULD_QSETS,
687 	.rxq_size	= 1024,
688 	.lro		= true,
689 	.add		= cxgbit_uld_add,
690 	.state_change	= cxgbit_uld_state_change,
691 	.lro_rx_handler = cxgbit_uld_lro_rx_handler,
692 	.lro_flush	= cxgbit_uld_lro_flush,
693 };
694 
695 #ifdef CONFIG_CHELSIO_T4_DCB
696 static struct notifier_block cxgbit_dcbevent_nb = {
697 	.notifier_call = cxgbit_dcbevent_notify,
698 };
699 #endif
700 
701 static int __init cxgbit_init(void)
702 {
703 	cxgb4_register_uld(CXGB4_ULD_ISCSIT, &cxgbit_uld_info);
704 	iscsit_register_transport(&cxgbit_transport);
705 
706 #ifdef CONFIG_CHELSIO_T4_DCB
707 	pr_info("%s dcb enabled.\n", DRV_NAME);
708 	register_dcbevent_notifier(&cxgbit_dcbevent_nb);
709 #endif
710 	BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, cb) <
711 		     sizeof(union cxgbit_skb_cb));
712 	return 0;
713 }
714 
715 static void __exit cxgbit_exit(void)
716 {
717 	struct cxgbit_device *cdev, *tmp;
718 
719 #ifdef CONFIG_CHELSIO_T4_DCB
720 	unregister_dcbevent_notifier(&cxgbit_dcbevent_nb);
721 #endif
722 	mutex_lock(&cdev_list_lock);
723 	list_for_each_entry_safe(cdev, tmp, &cdev_list_head, list) {
724 		list_del(&cdev->list);
725 		cxgbit_put_cdev(cdev);
726 	}
727 	mutex_unlock(&cdev_list_lock);
728 	iscsit_unregister_transport(&cxgbit_transport);
729 	cxgb4_unregister_uld(CXGB4_ULD_ISCSIT);
730 }
731 
732 module_init(cxgbit_init);
733 module_exit(cxgbit_exit);
734 
735 MODULE_DESCRIPTION("Chelsio iSCSI target offload driver");
736 MODULE_AUTHOR("Chelsio Communications");
737 MODULE_VERSION(DRV_VERSION);
738 MODULE_LICENSE("GPL");
739