xref: /openbmc/linux/drivers/scsi/cxgbi/libcxgbi.c (revision 89df62c3)
1 /*
2  * libcxgbi.c: Chelsio common library for T3/T4 iSCSI driver.
3  *
4  * Copyright (c) 2010-2015 Chelsio Communications, Inc.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation.
9  *
10  * Written by: Karen Xie (kxie@chelsio.com)
11  * Written by: Rakesh Ranjan (rranjan@chelsio.com)
12  */
13 
14 #define pr_fmt(fmt)	KBUILD_MODNAME ":%s: " fmt, __func__
15 
16 #include <linux/skbuff.h>
17 #include <linux/crypto.h>
18 #include <linux/scatterlist.h>
19 #include <linux/pci.h>
20 #include <scsi/scsi.h>
21 #include <scsi/scsi_cmnd.h>
22 #include <scsi/scsi_host.h>
23 #include <linux/if_vlan.h>
24 #include <linux/inet.h>
25 #include <net/dst.h>
26 #include <net/route.h>
27 #include <net/ipv6.h>
28 #include <net/ip6_route.h>
29 #include <net/addrconf.h>
30 
31 #include <linux/inetdevice.h>	/* ip_dev_find */
32 #include <linux/module.h>
33 #include <net/tcp.h>
34 
35 static unsigned int dbg_level;
36 
37 #include "libcxgbi.h"
38 
39 #define DRV_MODULE_NAME		"libcxgbi"
40 #define DRV_MODULE_DESC		"Chelsio iSCSI driver library"
41 #define DRV_MODULE_VERSION	"0.9.1-ko"
42 #define DRV_MODULE_RELDATE	"Apr. 2015"
43 
44 static char version[] =
45 	DRV_MODULE_DESC " " DRV_MODULE_NAME
46 	" v" DRV_MODULE_VERSION " (" DRV_MODULE_RELDATE ")\n";
47 
48 MODULE_AUTHOR("Chelsio Communications, Inc.");
49 MODULE_DESCRIPTION(DRV_MODULE_DESC);
50 MODULE_VERSION(DRV_MODULE_VERSION);
51 MODULE_LICENSE("GPL");
52 
53 module_param(dbg_level, uint, 0644);
54 MODULE_PARM_DESC(dbg_level, "libiscsi debug level (default=0)");
55 
56 
57 /*
58  * cxgbi device management
59  * maintains a list of the cxgbi devices
60  */
61 static LIST_HEAD(cdev_list);
62 static DEFINE_MUTEX(cdev_mutex);
63 
64 static LIST_HEAD(cdev_rcu_list);
65 static DEFINE_SPINLOCK(cdev_rcu_lock);
66 
67 static inline void cxgbi_decode_sw_tag(u32 sw_tag, int *idx, int *age)
68 {
69 	if (age)
70 		*age = sw_tag & 0x7FFF;
71 	if (idx)
72 		*idx = (sw_tag >> 16) & 0x7FFF;
73 }
74 
75 int cxgbi_device_portmap_create(struct cxgbi_device *cdev, unsigned int base,
76 				unsigned int max_conn)
77 {
78 	struct cxgbi_ports_map *pmap = &cdev->pmap;
79 
80 	pmap->port_csk = kvzalloc(array_size(max_conn,
81 					     sizeof(struct cxgbi_sock *)),
82 				  GFP_KERNEL | __GFP_NOWARN);
83 	if (!pmap->port_csk) {
84 		pr_warn("cdev 0x%p, portmap OOM %u.\n", cdev, max_conn);
85 		return -ENOMEM;
86 	}
87 
88 	pmap->max_connect = max_conn;
89 	pmap->sport_base = base;
90 	spin_lock_init(&pmap->lock);
91 	return 0;
92 }
93 EXPORT_SYMBOL_GPL(cxgbi_device_portmap_create);
94 
95 void cxgbi_device_portmap_cleanup(struct cxgbi_device *cdev)
96 {
97 	struct cxgbi_ports_map *pmap = &cdev->pmap;
98 	struct cxgbi_sock *csk;
99 	int i;
100 
101 	for (i = 0; i < pmap->max_connect; i++) {
102 		if (pmap->port_csk[i]) {
103 			csk = pmap->port_csk[i];
104 			pmap->port_csk[i] = NULL;
105 			log_debug(1 << CXGBI_DBG_SOCK,
106 				"csk 0x%p, cdev 0x%p, offload down.\n",
107 				csk, cdev);
108 			spin_lock_bh(&csk->lock);
109 			cxgbi_sock_set_flag(csk, CTPF_OFFLOAD_DOWN);
110 			cxgbi_sock_closed(csk);
111 			spin_unlock_bh(&csk->lock);
112 			cxgbi_sock_put(csk);
113 		}
114 	}
115 }
116 EXPORT_SYMBOL_GPL(cxgbi_device_portmap_cleanup);
117 
118 static inline void cxgbi_device_destroy(struct cxgbi_device *cdev)
119 {
120 	log_debug(1 << CXGBI_DBG_DEV,
121 		"cdev 0x%p, p# %u.\n", cdev, cdev->nports);
122 	cxgbi_hbas_remove(cdev);
123 	cxgbi_device_portmap_cleanup(cdev);
124 	if (cdev->cdev2ppm)
125 		cxgbi_ppm_release(cdev->cdev2ppm(cdev));
126 	if (cdev->pmap.max_connect)
127 		kvfree(cdev->pmap.port_csk);
128 	kfree(cdev);
129 }
130 
131 struct cxgbi_device *cxgbi_device_register(unsigned int extra,
132 					   unsigned int nports)
133 {
134 	struct cxgbi_device *cdev;
135 
136 	cdev = kzalloc(sizeof(*cdev) + extra + nports *
137 			(sizeof(struct cxgbi_hba *) +
138 			 sizeof(struct net_device *)),
139 			GFP_KERNEL);
140 	if (!cdev) {
141 		pr_warn("nport %d, OOM.\n", nports);
142 		return NULL;
143 	}
144 	cdev->ports = (struct net_device **)(cdev + 1);
145 	cdev->hbas = (struct cxgbi_hba **)(((char*)cdev->ports) + nports *
146 						sizeof(struct net_device *));
147 	if (extra)
148 		cdev->dd_data = ((char *)cdev->hbas) +
149 				nports * sizeof(struct cxgbi_hba *);
150 	spin_lock_init(&cdev->pmap.lock);
151 
152 	mutex_lock(&cdev_mutex);
153 	list_add_tail(&cdev->list_head, &cdev_list);
154 	mutex_unlock(&cdev_mutex);
155 
156 	spin_lock(&cdev_rcu_lock);
157 	list_add_tail_rcu(&cdev->rcu_node, &cdev_rcu_list);
158 	spin_unlock(&cdev_rcu_lock);
159 
160 	log_debug(1 << CXGBI_DBG_DEV,
161 		"cdev 0x%p, p# %u.\n", cdev, nports);
162 	return cdev;
163 }
164 EXPORT_SYMBOL_GPL(cxgbi_device_register);
165 
166 void cxgbi_device_unregister(struct cxgbi_device *cdev)
167 {
168 	log_debug(1 << CXGBI_DBG_DEV,
169 		"cdev 0x%p, p# %u,%s.\n",
170 		cdev, cdev->nports, cdev->nports ? cdev->ports[0]->name : "");
171 
172 	mutex_lock(&cdev_mutex);
173 	list_del(&cdev->list_head);
174 	mutex_unlock(&cdev_mutex);
175 
176 	spin_lock(&cdev_rcu_lock);
177 	list_del_rcu(&cdev->rcu_node);
178 	spin_unlock(&cdev_rcu_lock);
179 	synchronize_rcu();
180 
181 	cxgbi_device_destroy(cdev);
182 }
183 EXPORT_SYMBOL_GPL(cxgbi_device_unregister);
184 
185 void cxgbi_device_unregister_all(unsigned int flag)
186 {
187 	struct cxgbi_device *cdev, *tmp;
188 
189 	mutex_lock(&cdev_mutex);
190 	list_for_each_entry_safe(cdev, tmp, &cdev_list, list_head) {
191 		if ((cdev->flags & flag) == flag) {
192 			mutex_unlock(&cdev_mutex);
193 			cxgbi_device_unregister(cdev);
194 			mutex_lock(&cdev_mutex);
195 		}
196 	}
197 	mutex_unlock(&cdev_mutex);
198 }
199 EXPORT_SYMBOL_GPL(cxgbi_device_unregister_all);
200 
201 struct cxgbi_device *cxgbi_device_find_by_lldev(void *lldev)
202 {
203 	struct cxgbi_device *cdev, *tmp;
204 
205 	mutex_lock(&cdev_mutex);
206 	list_for_each_entry_safe(cdev, tmp, &cdev_list, list_head) {
207 		if (cdev->lldev == lldev) {
208 			mutex_unlock(&cdev_mutex);
209 			return cdev;
210 		}
211 	}
212 	mutex_unlock(&cdev_mutex);
213 
214 	log_debug(1 << CXGBI_DBG_DEV,
215 		"lldev 0x%p, NO match found.\n", lldev);
216 	return NULL;
217 }
218 EXPORT_SYMBOL_GPL(cxgbi_device_find_by_lldev);
219 
220 struct cxgbi_device *cxgbi_device_find_by_netdev(struct net_device *ndev,
221 						 int *port)
222 {
223 	struct net_device *vdev = NULL;
224 	struct cxgbi_device *cdev, *tmp;
225 	int i;
226 
227 	if (is_vlan_dev(ndev)) {
228 		vdev = ndev;
229 		ndev = vlan_dev_real_dev(ndev);
230 		log_debug(1 << CXGBI_DBG_DEV,
231 			"vlan dev %s -> %s.\n", vdev->name, ndev->name);
232 	}
233 
234 	mutex_lock(&cdev_mutex);
235 	list_for_each_entry_safe(cdev, tmp, &cdev_list, list_head) {
236 		for (i = 0; i < cdev->nports; i++) {
237 			if (ndev == cdev->ports[i]) {
238 				cdev->hbas[i]->vdev = vdev;
239 				mutex_unlock(&cdev_mutex);
240 				if (port)
241 					*port = i;
242 				return cdev;
243 			}
244 		}
245 	}
246 	mutex_unlock(&cdev_mutex);
247 	log_debug(1 << CXGBI_DBG_DEV,
248 		"ndev 0x%p, %s, NO match found.\n", ndev, ndev->name);
249 	return NULL;
250 }
251 EXPORT_SYMBOL_GPL(cxgbi_device_find_by_netdev);
252 
253 struct cxgbi_device *cxgbi_device_find_by_netdev_rcu(struct net_device *ndev,
254 						     int *port)
255 {
256 	struct net_device *vdev = NULL;
257 	struct cxgbi_device *cdev;
258 	int i;
259 
260 	if (is_vlan_dev(ndev)) {
261 		vdev = ndev;
262 		ndev = vlan_dev_real_dev(ndev);
263 		pr_info("vlan dev %s -> %s.\n", vdev->name, ndev->name);
264 	}
265 
266 	rcu_read_lock();
267 	list_for_each_entry_rcu(cdev, &cdev_rcu_list, rcu_node) {
268 		for (i = 0; i < cdev->nports; i++) {
269 			if (ndev == cdev->ports[i]) {
270 				cdev->hbas[i]->vdev = vdev;
271 				rcu_read_unlock();
272 				if (port)
273 					*port = i;
274 				return cdev;
275 			}
276 		}
277 	}
278 	rcu_read_unlock();
279 
280 	log_debug(1 << CXGBI_DBG_DEV,
281 		  "ndev 0x%p, %s, NO match found.\n", ndev, ndev->name);
282 	return NULL;
283 }
284 EXPORT_SYMBOL_GPL(cxgbi_device_find_by_netdev_rcu);
285 
286 static struct cxgbi_device *cxgbi_device_find_by_mac(struct net_device *ndev,
287 						     int *port)
288 {
289 	struct net_device *vdev = NULL;
290 	struct cxgbi_device *cdev, *tmp;
291 	int i;
292 
293 	if (is_vlan_dev(ndev)) {
294 		vdev = ndev;
295 		ndev = vlan_dev_real_dev(ndev);
296 		pr_info("vlan dev %s -> %s.\n", vdev->name, ndev->name);
297 	}
298 
299 	mutex_lock(&cdev_mutex);
300 	list_for_each_entry_safe(cdev, tmp, &cdev_list, list_head) {
301 		for (i = 0; i < cdev->nports; i++) {
302 			if (!memcmp(ndev->dev_addr, cdev->ports[i]->dev_addr,
303 				    MAX_ADDR_LEN)) {
304 				cdev->hbas[i]->vdev = vdev;
305 				mutex_unlock(&cdev_mutex);
306 				if (port)
307 					*port = i;
308 				return cdev;
309 			}
310 		}
311 	}
312 	mutex_unlock(&cdev_mutex);
313 	log_debug(1 << CXGBI_DBG_DEV,
314 		  "ndev 0x%p, %s, NO match mac found.\n",
315 		  ndev, ndev->name);
316 	return NULL;
317 }
318 
319 void cxgbi_hbas_remove(struct cxgbi_device *cdev)
320 {
321 	int i;
322 	struct cxgbi_hba *chba;
323 
324 	log_debug(1 << CXGBI_DBG_DEV,
325 		"cdev 0x%p, p#%u.\n", cdev, cdev->nports);
326 
327 	for (i = 0; i < cdev->nports; i++) {
328 		chba = cdev->hbas[i];
329 		if (chba) {
330 			cdev->hbas[i] = NULL;
331 			iscsi_host_remove(chba->shost, false);
332 			pci_dev_put(cdev->pdev);
333 			iscsi_host_free(chba->shost);
334 		}
335 	}
336 }
337 EXPORT_SYMBOL_GPL(cxgbi_hbas_remove);
338 
339 int cxgbi_hbas_add(struct cxgbi_device *cdev, u64 max_lun,
340 		unsigned int max_conns, const struct scsi_host_template *sht,
341 		struct scsi_transport_template *stt)
342 {
343 	struct cxgbi_hba *chba;
344 	struct Scsi_Host *shost;
345 	int i, err;
346 
347 	log_debug(1 << CXGBI_DBG_DEV, "cdev 0x%p, p#%u.\n", cdev, cdev->nports);
348 
349 	for (i = 0; i < cdev->nports; i++) {
350 		shost = iscsi_host_alloc(sht, sizeof(*chba), 1);
351 		if (!shost) {
352 			pr_info("0x%p, p%d, %s, host alloc failed.\n",
353 				cdev, i, cdev->ports[i]->name);
354 			err = -ENOMEM;
355 			goto err_out;
356 		}
357 
358 		shost->transportt = stt;
359 		shost->max_lun = max_lun;
360 		shost->max_id = max_conns - 1;
361 		shost->max_channel = 0;
362 		shost->max_cmd_len = SCSI_MAX_VARLEN_CDB_SIZE;
363 
364 		chba = iscsi_host_priv(shost);
365 		chba->cdev = cdev;
366 		chba->ndev = cdev->ports[i];
367 		chba->shost = shost;
368 
369 		shost->can_queue = sht->can_queue - ISCSI_MGMT_CMDS_MAX;
370 
371 		log_debug(1 << CXGBI_DBG_DEV,
372 			"cdev 0x%p, p#%d %s: chba 0x%p.\n",
373 			cdev, i, cdev->ports[i]->name, chba);
374 
375 		pci_dev_get(cdev->pdev);
376 		err = iscsi_host_add(shost, &cdev->pdev->dev);
377 		if (err) {
378 			pr_info("cdev 0x%p, p#%d %s, host add failed.\n",
379 				cdev, i, cdev->ports[i]->name);
380 			pci_dev_put(cdev->pdev);
381 			scsi_host_put(shost);
382 			goto  err_out;
383 		}
384 
385 		cdev->hbas[i] = chba;
386 	}
387 
388 	return 0;
389 
390 err_out:
391 	cxgbi_hbas_remove(cdev);
392 	return err;
393 }
394 EXPORT_SYMBOL_GPL(cxgbi_hbas_add);
395 
396 /*
397  * iSCSI offload
398  *
399  * - source port management
400  *   To find a free source port in the port allocation map we use a very simple
401  *   rotor scheme to look for the next free port.
402  *
403  *   If a source port has been specified make sure that it doesn't collide with
404  *   our normal source port allocation map.  If it's outside the range of our
405  *   allocation/deallocation scheme just let them use it.
406  *
407  *   If the source port is outside our allocation range, the caller is
408  *   responsible for keeping track of their port usage.
409  */
410 
411 static struct cxgbi_sock *find_sock_on_port(struct cxgbi_device *cdev,
412 					    unsigned char port_id)
413 {
414 	struct cxgbi_ports_map *pmap = &cdev->pmap;
415 	unsigned int i;
416 	unsigned int used;
417 
418 	if (!pmap->max_connect || !pmap->used)
419 		return NULL;
420 
421 	spin_lock_bh(&pmap->lock);
422 	used = pmap->used;
423 	for (i = 0; used && i < pmap->max_connect; i++) {
424 		struct cxgbi_sock *csk = pmap->port_csk[i];
425 
426 		if (csk) {
427 			if (csk->port_id == port_id) {
428 				spin_unlock_bh(&pmap->lock);
429 				return csk;
430 			}
431 			used--;
432 		}
433 	}
434 	spin_unlock_bh(&pmap->lock);
435 
436 	return NULL;
437 }
438 
439 static int sock_get_port(struct cxgbi_sock *csk)
440 {
441 	struct cxgbi_device *cdev = csk->cdev;
442 	struct cxgbi_ports_map *pmap = &cdev->pmap;
443 	unsigned int start;
444 	int idx;
445 	__be16 *port;
446 
447 	if (!pmap->max_connect) {
448 		pr_err("cdev 0x%p, p#%u %s, NO port map.\n",
449 			   cdev, csk->port_id, cdev->ports[csk->port_id]->name);
450 		return -EADDRNOTAVAIL;
451 	}
452 
453 	if (csk->csk_family == AF_INET)
454 		port = &csk->saddr.sin_port;
455 	else /* ipv6 */
456 		port = &csk->saddr6.sin6_port;
457 
458 	if (*port) {
459 		pr_err("source port NON-ZERO %u.\n",
460 			ntohs(*port));
461 		return -EADDRINUSE;
462 	}
463 
464 	spin_lock_bh(&pmap->lock);
465 	if (pmap->used >= pmap->max_connect) {
466 		spin_unlock_bh(&pmap->lock);
467 		pr_info("cdev 0x%p, p#%u %s, ALL ports used.\n",
468 			cdev, csk->port_id, cdev->ports[csk->port_id]->name);
469 		return -EADDRNOTAVAIL;
470 	}
471 
472 	start = idx = pmap->next;
473 	do {
474 		if (++idx >= pmap->max_connect)
475 			idx = 0;
476 		if (!pmap->port_csk[idx]) {
477 			pmap->used++;
478 			*port = htons(pmap->sport_base + idx);
479 			pmap->next = idx;
480 			pmap->port_csk[idx] = csk;
481 			spin_unlock_bh(&pmap->lock);
482 			cxgbi_sock_get(csk);
483 			log_debug(1 << CXGBI_DBG_SOCK,
484 				"cdev 0x%p, p#%u %s, p %u, %u.\n",
485 				cdev, csk->port_id,
486 				cdev->ports[csk->port_id]->name,
487 				pmap->sport_base + idx, pmap->next);
488 			return 0;
489 		}
490 	} while (idx != start);
491 	spin_unlock_bh(&pmap->lock);
492 
493 	/* should not happen */
494 	pr_warn("cdev 0x%p, p#%u %s, next %u?\n",
495 		cdev, csk->port_id, cdev->ports[csk->port_id]->name,
496 		pmap->next);
497 	return -EADDRNOTAVAIL;
498 }
499 
500 static void sock_put_port(struct cxgbi_sock *csk)
501 {
502 	struct cxgbi_device *cdev = csk->cdev;
503 	struct cxgbi_ports_map *pmap = &cdev->pmap;
504 	__be16 *port;
505 
506 	if (csk->csk_family == AF_INET)
507 		port = &csk->saddr.sin_port;
508 	else /* ipv6 */
509 		port = &csk->saddr6.sin6_port;
510 
511 	if (*port) {
512 		int idx = ntohs(*port) - pmap->sport_base;
513 
514 		*port = 0;
515 		if (idx < 0 || idx >= pmap->max_connect) {
516 			pr_err("cdev 0x%p, p#%u %s, port %u OOR.\n",
517 				cdev, csk->port_id,
518 				cdev->ports[csk->port_id]->name,
519 				ntohs(*port));
520 			return;
521 		}
522 
523 		spin_lock_bh(&pmap->lock);
524 		pmap->port_csk[idx] = NULL;
525 		pmap->used--;
526 		spin_unlock_bh(&pmap->lock);
527 
528 		log_debug(1 << CXGBI_DBG_SOCK,
529 			"cdev 0x%p, p#%u %s, release %u.\n",
530 			cdev, csk->port_id, cdev->ports[csk->port_id]->name,
531 			pmap->sport_base + idx);
532 
533 		cxgbi_sock_put(csk);
534 	}
535 }
536 
537 /*
538  * iscsi tcp connection
539  */
540 void cxgbi_sock_free_cpl_skbs(struct cxgbi_sock *csk)
541 {
542 	if (csk->cpl_close) {
543 		kfree_skb(csk->cpl_close);
544 		csk->cpl_close = NULL;
545 	}
546 	if (csk->cpl_abort_req) {
547 		kfree_skb(csk->cpl_abort_req);
548 		csk->cpl_abort_req = NULL;
549 	}
550 	if (csk->cpl_abort_rpl) {
551 		kfree_skb(csk->cpl_abort_rpl);
552 		csk->cpl_abort_rpl = NULL;
553 	}
554 }
555 EXPORT_SYMBOL_GPL(cxgbi_sock_free_cpl_skbs);
556 
557 static struct cxgbi_sock *cxgbi_sock_create(struct cxgbi_device *cdev)
558 {
559 	struct cxgbi_sock *csk = kzalloc(sizeof(*csk), GFP_NOIO);
560 
561 	if (!csk) {
562 		pr_info("alloc csk %zu failed.\n", sizeof(*csk));
563 		return NULL;
564 	}
565 
566 	if (cdev->csk_alloc_cpls(csk) < 0) {
567 		pr_info("csk 0x%p, alloc cpls failed.\n", csk);
568 		kfree(csk);
569 		return NULL;
570 	}
571 
572 	spin_lock_init(&csk->lock);
573 	kref_init(&csk->refcnt);
574 	skb_queue_head_init(&csk->receive_queue);
575 	skb_queue_head_init(&csk->write_queue);
576 	timer_setup(&csk->retry_timer, NULL, 0);
577 	init_completion(&csk->cmpl);
578 	rwlock_init(&csk->callback_lock);
579 	csk->cdev = cdev;
580 	csk->flags = 0;
581 	cxgbi_sock_set_state(csk, CTP_CLOSED);
582 
583 	log_debug(1 << CXGBI_DBG_SOCK, "cdev 0x%p, new csk 0x%p.\n", cdev, csk);
584 
585 	return csk;
586 }
587 
588 static struct rtable *find_route_ipv4(struct flowi4 *fl4,
589 				      __be32 saddr, __be32 daddr,
590 				      __be16 sport, __be16 dport, u8 tos,
591 				      int ifindex)
592 {
593 	struct rtable *rt;
594 
595 	rt = ip_route_output_ports(&init_net, fl4, NULL, daddr, saddr,
596 				   dport, sport, IPPROTO_TCP, tos, ifindex);
597 	if (IS_ERR(rt))
598 		return NULL;
599 
600 	return rt;
601 }
602 
603 static struct cxgbi_sock *
604 cxgbi_check_route(struct sockaddr *dst_addr, int ifindex)
605 {
606 	struct sockaddr_in *daddr = (struct sockaddr_in *)dst_addr;
607 	struct dst_entry *dst;
608 	struct net_device *ndev;
609 	struct cxgbi_device *cdev;
610 	struct rtable *rt = NULL;
611 	struct neighbour *n;
612 	struct flowi4 fl4;
613 	struct cxgbi_sock *csk = NULL;
614 	unsigned int mtu = 0;
615 	int port = 0xFFFF;
616 	int err = 0;
617 
618 	rt = find_route_ipv4(&fl4, 0, daddr->sin_addr.s_addr, 0,
619 			     daddr->sin_port, 0, ifindex);
620 	if (!rt) {
621 		pr_info("no route to ipv4 0x%x, port %u.\n",
622 			be32_to_cpu(daddr->sin_addr.s_addr),
623 			be16_to_cpu(daddr->sin_port));
624 		err = -ENETUNREACH;
625 		goto err_out;
626 	}
627 	dst = &rt->dst;
628 	n = dst_neigh_lookup(dst, &daddr->sin_addr.s_addr);
629 	if (!n) {
630 		err = -ENODEV;
631 		goto rel_rt;
632 	}
633 	ndev = n->dev;
634 
635 	if (rt->rt_flags & (RTCF_MULTICAST | RTCF_BROADCAST)) {
636 		pr_info("multi-cast route %pI4, port %u, dev %s.\n",
637 			&daddr->sin_addr.s_addr, ntohs(daddr->sin_port),
638 			ndev->name);
639 		err = -ENETUNREACH;
640 		goto rel_neigh;
641 	}
642 
643 	if (ndev->flags & IFF_LOOPBACK) {
644 		ndev = ip_dev_find(&init_net, daddr->sin_addr.s_addr);
645 		if (!ndev) {
646 			err = -ENETUNREACH;
647 			goto rel_neigh;
648 		}
649 		mtu = ndev->mtu;
650 		pr_info("rt dev %s, loopback -> %s, mtu %u.\n",
651 			n->dev->name, ndev->name, mtu);
652 	}
653 
654 	if (!(ndev->flags & IFF_UP) || !netif_carrier_ok(ndev)) {
655 		pr_info("%s interface not up.\n", ndev->name);
656 		err = -ENETDOWN;
657 		goto rel_neigh;
658 	}
659 
660 	cdev = cxgbi_device_find_by_netdev(ndev, &port);
661 	if (!cdev)
662 		cdev = cxgbi_device_find_by_mac(ndev, &port);
663 	if (!cdev) {
664 		pr_info("dst %pI4, %s, NOT cxgbi device.\n",
665 			&daddr->sin_addr.s_addr, ndev->name);
666 		err = -ENETUNREACH;
667 		goto rel_neigh;
668 	}
669 	log_debug(1 << CXGBI_DBG_SOCK,
670 		"route to %pI4 :%u, ndev p#%d,%s, cdev 0x%p.\n",
671 		&daddr->sin_addr.s_addr, ntohs(daddr->sin_port),
672 			   port, ndev->name, cdev);
673 
674 	csk = cxgbi_sock_create(cdev);
675 	if (!csk) {
676 		err = -ENOMEM;
677 		goto rel_neigh;
678 	}
679 	csk->cdev = cdev;
680 	csk->port_id = port;
681 	csk->mtu = mtu;
682 	csk->dst = dst;
683 
684 	csk->csk_family = AF_INET;
685 	csk->daddr.sin_addr.s_addr = daddr->sin_addr.s_addr;
686 	csk->daddr.sin_port = daddr->sin_port;
687 	csk->daddr.sin_family = daddr->sin_family;
688 	csk->saddr.sin_family = daddr->sin_family;
689 	csk->saddr.sin_addr.s_addr = fl4.saddr;
690 	neigh_release(n);
691 
692 	return csk;
693 
694 rel_neigh:
695 	neigh_release(n);
696 
697 rel_rt:
698 	ip_rt_put(rt);
699 err_out:
700 	return ERR_PTR(err);
701 }
702 
703 #if IS_ENABLED(CONFIG_IPV6)
704 static struct rt6_info *find_route_ipv6(const struct in6_addr *saddr,
705 					const struct in6_addr *daddr,
706 					int ifindex)
707 {
708 	struct flowi6 fl;
709 
710 	memset(&fl, 0, sizeof(fl));
711 	fl.flowi6_oif = ifindex;
712 	if (saddr)
713 		memcpy(&fl.saddr, saddr, sizeof(struct in6_addr));
714 	if (daddr)
715 		memcpy(&fl.daddr, daddr, sizeof(struct in6_addr));
716 	return (struct rt6_info *)ip6_route_output(&init_net, NULL, &fl);
717 }
718 
719 static struct cxgbi_sock *
720 cxgbi_check_route6(struct sockaddr *dst_addr, int ifindex)
721 {
722 	struct sockaddr_in6 *daddr6 = (struct sockaddr_in6 *)dst_addr;
723 	struct dst_entry *dst;
724 	struct net_device *ndev;
725 	struct cxgbi_device *cdev;
726 	struct rt6_info *rt = NULL;
727 	struct neighbour *n;
728 	struct in6_addr pref_saddr;
729 	struct cxgbi_sock *csk = NULL;
730 	unsigned int mtu = 0;
731 	int port = 0xFFFF;
732 	int err = 0;
733 
734 	rt = find_route_ipv6(NULL, &daddr6->sin6_addr, ifindex);
735 
736 	if (!rt) {
737 		pr_info("no route to ipv6 %pI6 port %u\n",
738 			daddr6->sin6_addr.s6_addr,
739 			be16_to_cpu(daddr6->sin6_port));
740 		err = -ENETUNREACH;
741 		goto err_out;
742 	}
743 
744 	dst = &rt->dst;
745 
746 	n = dst_neigh_lookup(dst, &daddr6->sin6_addr);
747 
748 	if (!n) {
749 		pr_info("%pI6, port %u, dst no neighbour.\n",
750 			daddr6->sin6_addr.s6_addr,
751 			be16_to_cpu(daddr6->sin6_port));
752 		err = -ENETUNREACH;
753 		goto rel_rt;
754 	}
755 	ndev = n->dev;
756 
757 	if (!(ndev->flags & IFF_UP) || !netif_carrier_ok(ndev)) {
758 		pr_info("%s interface not up.\n", ndev->name);
759 		err = -ENETDOWN;
760 		goto rel_rt;
761 	}
762 
763 	if (ipv6_addr_is_multicast(&daddr6->sin6_addr)) {
764 		pr_info("multi-cast route %pI6 port %u, dev %s.\n",
765 			daddr6->sin6_addr.s6_addr,
766 			ntohs(daddr6->sin6_port), ndev->name);
767 		err = -ENETUNREACH;
768 		goto rel_rt;
769 	}
770 
771 	cdev = cxgbi_device_find_by_netdev(ndev, &port);
772 	if (!cdev)
773 		cdev = cxgbi_device_find_by_mac(ndev, &port);
774 	if (!cdev) {
775 		pr_info("dst %pI6 %s, NOT cxgbi device.\n",
776 			daddr6->sin6_addr.s6_addr, ndev->name);
777 		err = -ENETUNREACH;
778 		goto rel_rt;
779 	}
780 	log_debug(1 << CXGBI_DBG_SOCK,
781 		  "route to %pI6 :%u, ndev p#%d,%s, cdev 0x%p.\n",
782 		  daddr6->sin6_addr.s6_addr, ntohs(daddr6->sin6_port), port,
783 		  ndev->name, cdev);
784 
785 	csk = cxgbi_sock_create(cdev);
786 	if (!csk) {
787 		err = -ENOMEM;
788 		goto rel_rt;
789 	}
790 	csk->cdev = cdev;
791 	csk->port_id = port;
792 	csk->mtu = mtu;
793 	csk->dst = dst;
794 
795 	rt6_get_prefsrc(rt, &pref_saddr);
796 	if (ipv6_addr_any(&pref_saddr)) {
797 		struct inet6_dev *idev = ip6_dst_idev((struct dst_entry *)rt);
798 
799 		err = ipv6_dev_get_saddr(&init_net, idev ? idev->dev : NULL,
800 					 &daddr6->sin6_addr, 0, &pref_saddr);
801 		if (err) {
802 			pr_info("failed to get source address to reach %pI6\n",
803 				&daddr6->sin6_addr);
804 			goto rel_rt;
805 		}
806 	}
807 
808 	csk->csk_family = AF_INET6;
809 	csk->daddr6.sin6_addr = daddr6->sin6_addr;
810 	csk->daddr6.sin6_port = daddr6->sin6_port;
811 	csk->daddr6.sin6_family = daddr6->sin6_family;
812 	csk->saddr6.sin6_family = daddr6->sin6_family;
813 	csk->saddr6.sin6_addr = pref_saddr;
814 
815 	neigh_release(n);
816 	return csk;
817 
818 rel_rt:
819 	if (n)
820 		neigh_release(n);
821 
822 	ip6_rt_put(rt);
823 	if (csk)
824 		cxgbi_sock_closed(csk);
825 err_out:
826 	return ERR_PTR(err);
827 }
828 #endif /* IS_ENABLED(CONFIG_IPV6) */
829 
830 void cxgbi_sock_established(struct cxgbi_sock *csk, unsigned int snd_isn,
831 			unsigned int opt)
832 {
833 	csk->write_seq = csk->snd_nxt = csk->snd_una = snd_isn;
834 	dst_confirm(csk->dst);
835 	smp_mb();
836 	cxgbi_sock_set_state(csk, CTP_ESTABLISHED);
837 }
838 EXPORT_SYMBOL_GPL(cxgbi_sock_established);
839 
840 static void cxgbi_inform_iscsi_conn_closing(struct cxgbi_sock *csk)
841 {
842 	log_debug(1 << CXGBI_DBG_SOCK,
843 		"csk 0x%p, state %u, flags 0x%lx, conn 0x%p.\n",
844 		csk, csk->state, csk->flags, csk->user_data);
845 
846 	if (csk->state != CTP_ESTABLISHED) {
847 		read_lock_bh(&csk->callback_lock);
848 		if (csk->user_data)
849 			iscsi_conn_failure(csk->user_data,
850 					ISCSI_ERR_TCP_CONN_CLOSE);
851 		read_unlock_bh(&csk->callback_lock);
852 	}
853 }
854 
855 void cxgbi_sock_closed(struct cxgbi_sock *csk)
856 {
857 	log_debug(1 << CXGBI_DBG_SOCK, "csk 0x%p,%u,0x%lx,%u.\n",
858 		csk, (csk)->state, (csk)->flags, (csk)->tid);
859 	cxgbi_sock_set_flag(csk, CTPF_ACTIVE_CLOSE_NEEDED);
860 	if (csk->state == CTP_ACTIVE_OPEN || csk->state == CTP_CLOSED)
861 		return;
862 	if (csk->saddr.sin_port)
863 		sock_put_port(csk);
864 	if (csk->dst)
865 		dst_release(csk->dst);
866 	csk->cdev->csk_release_offload_resources(csk);
867 	cxgbi_sock_set_state(csk, CTP_CLOSED);
868 	cxgbi_inform_iscsi_conn_closing(csk);
869 	cxgbi_sock_put(csk);
870 }
871 EXPORT_SYMBOL_GPL(cxgbi_sock_closed);
872 
873 static void need_active_close(struct cxgbi_sock *csk)
874 {
875 	int data_lost;
876 	int close_req = 0;
877 
878 	log_debug(1 << CXGBI_DBG_SOCK, "csk 0x%p,%u,0x%lx,%u.\n",
879 		csk, (csk)->state, (csk)->flags, (csk)->tid);
880 	spin_lock_bh(&csk->lock);
881 	if (csk->dst)
882 		dst_confirm(csk->dst);
883 	data_lost = skb_queue_len(&csk->receive_queue);
884 	__skb_queue_purge(&csk->receive_queue);
885 
886 	if (csk->state == CTP_ACTIVE_OPEN)
887 		cxgbi_sock_set_flag(csk, CTPF_ACTIVE_CLOSE_NEEDED);
888 	else if (csk->state == CTP_ESTABLISHED) {
889 		close_req = 1;
890 		cxgbi_sock_set_state(csk, CTP_ACTIVE_CLOSE);
891 	} else if (csk->state == CTP_PASSIVE_CLOSE) {
892 		close_req = 1;
893 		cxgbi_sock_set_state(csk, CTP_CLOSE_WAIT_2);
894 	}
895 
896 	if (close_req) {
897 		if (!cxgbi_sock_flag(csk, CTPF_LOGOUT_RSP_RCVD) ||
898 		    data_lost)
899 			csk->cdev->csk_send_abort_req(csk);
900 		else
901 			csk->cdev->csk_send_close_req(csk);
902 	}
903 
904 	spin_unlock_bh(&csk->lock);
905 }
906 
907 void cxgbi_sock_fail_act_open(struct cxgbi_sock *csk, int errno)
908 {
909 	pr_info("csk 0x%p,%u,%lx, %pI4:%u-%pI4:%u, err %d.\n",
910 			csk, csk->state, csk->flags,
911 			&csk->saddr.sin_addr.s_addr, csk->saddr.sin_port,
912 			&csk->daddr.sin_addr.s_addr, csk->daddr.sin_port,
913 			errno);
914 
915 	cxgbi_sock_set_state(csk, CTP_CONNECTING);
916 	csk->err = errno;
917 	cxgbi_sock_closed(csk);
918 }
919 EXPORT_SYMBOL_GPL(cxgbi_sock_fail_act_open);
920 
921 void cxgbi_sock_act_open_req_arp_failure(void *handle, struct sk_buff *skb)
922 {
923 	struct cxgbi_sock *csk = (struct cxgbi_sock *)skb->sk;
924 	struct module *owner = csk->cdev->owner;
925 
926 	log_debug(1 << CXGBI_DBG_SOCK, "csk 0x%p,%u,0x%lx,%u.\n",
927 		csk, (csk)->state, (csk)->flags, (csk)->tid);
928 	cxgbi_sock_get(csk);
929 	spin_lock_bh(&csk->lock);
930 	if (csk->state == CTP_ACTIVE_OPEN)
931 		cxgbi_sock_fail_act_open(csk, -EHOSTUNREACH);
932 	spin_unlock_bh(&csk->lock);
933 	cxgbi_sock_put(csk);
934 	__kfree_skb(skb);
935 
936 	module_put(owner);
937 }
938 EXPORT_SYMBOL_GPL(cxgbi_sock_act_open_req_arp_failure);
939 
940 void cxgbi_sock_rcv_abort_rpl(struct cxgbi_sock *csk)
941 {
942 	cxgbi_sock_get(csk);
943 	spin_lock_bh(&csk->lock);
944 
945 	cxgbi_sock_set_flag(csk, CTPF_ABORT_RPL_RCVD);
946 	if (cxgbi_sock_flag(csk, CTPF_ABORT_RPL_PENDING)) {
947 		cxgbi_sock_clear_flag(csk, CTPF_ABORT_RPL_PENDING);
948 		if (cxgbi_sock_flag(csk, CTPF_ABORT_REQ_RCVD))
949 			pr_err("csk 0x%p,%u,0x%lx,%u,ABT_RPL_RSS.\n",
950 			       csk, csk->state, csk->flags, csk->tid);
951 		cxgbi_sock_closed(csk);
952 	}
953 
954 	spin_unlock_bh(&csk->lock);
955 	cxgbi_sock_put(csk);
956 }
957 EXPORT_SYMBOL_GPL(cxgbi_sock_rcv_abort_rpl);
958 
959 void cxgbi_sock_rcv_peer_close(struct cxgbi_sock *csk)
960 {
961 	log_debug(1 << CXGBI_DBG_SOCK, "csk 0x%p,%u,0x%lx,%u.\n",
962 		csk, (csk)->state, (csk)->flags, (csk)->tid);
963 	cxgbi_sock_get(csk);
964 	spin_lock_bh(&csk->lock);
965 
966 	if (cxgbi_sock_flag(csk, CTPF_ABORT_RPL_PENDING))
967 		goto done;
968 
969 	switch (csk->state) {
970 	case CTP_ESTABLISHED:
971 		cxgbi_sock_set_state(csk, CTP_PASSIVE_CLOSE);
972 		break;
973 	case CTP_ACTIVE_CLOSE:
974 		cxgbi_sock_set_state(csk, CTP_CLOSE_WAIT_2);
975 		break;
976 	case CTP_CLOSE_WAIT_1:
977 		cxgbi_sock_closed(csk);
978 		break;
979 	case CTP_ABORTING:
980 		break;
981 	default:
982 		pr_err("csk 0x%p,%u,0x%lx,%u, bad state.\n",
983 			csk, csk->state, csk->flags, csk->tid);
984 	}
985 	cxgbi_inform_iscsi_conn_closing(csk);
986 done:
987 	spin_unlock_bh(&csk->lock);
988 	cxgbi_sock_put(csk);
989 }
990 EXPORT_SYMBOL_GPL(cxgbi_sock_rcv_peer_close);
991 
992 void cxgbi_sock_rcv_close_conn_rpl(struct cxgbi_sock *csk, u32 snd_nxt)
993 {
994 	log_debug(1 << CXGBI_DBG_SOCK, "csk 0x%p,%u,0x%lx,%u.\n",
995 		csk, (csk)->state, (csk)->flags, (csk)->tid);
996 	cxgbi_sock_get(csk);
997 	spin_lock_bh(&csk->lock);
998 
999 	csk->snd_una = snd_nxt - 1;
1000 	if (cxgbi_sock_flag(csk, CTPF_ABORT_RPL_PENDING))
1001 		goto done;
1002 
1003 	switch (csk->state) {
1004 	case CTP_ACTIVE_CLOSE:
1005 		cxgbi_sock_set_state(csk, CTP_CLOSE_WAIT_1);
1006 		break;
1007 	case CTP_CLOSE_WAIT_1:
1008 	case CTP_CLOSE_WAIT_2:
1009 		cxgbi_sock_closed(csk);
1010 		break;
1011 	case CTP_ABORTING:
1012 		break;
1013 	default:
1014 		pr_err("csk 0x%p,%u,0x%lx,%u, bad state.\n",
1015 			csk, csk->state, csk->flags, csk->tid);
1016 	}
1017 done:
1018 	spin_unlock_bh(&csk->lock);
1019 	cxgbi_sock_put(csk);
1020 }
1021 EXPORT_SYMBOL_GPL(cxgbi_sock_rcv_close_conn_rpl);
1022 
1023 void cxgbi_sock_rcv_wr_ack(struct cxgbi_sock *csk, unsigned int credits,
1024 			   unsigned int snd_una, int seq_chk)
1025 {
1026 	log_debug(1 << CXGBI_DBG_TOE | 1 << CXGBI_DBG_SOCK,
1027 			"csk 0x%p,%u,0x%lx,%u, cr %u,%u+%u, snd_una %u,%d.\n",
1028 			csk, csk->state, csk->flags, csk->tid, credits,
1029 			csk->wr_cred, csk->wr_una_cred, snd_una, seq_chk);
1030 
1031 	spin_lock_bh(&csk->lock);
1032 
1033 	csk->wr_cred += credits;
1034 	if (csk->wr_una_cred > csk->wr_max_cred - csk->wr_cred)
1035 		csk->wr_una_cred = csk->wr_max_cred - csk->wr_cred;
1036 
1037 	while (credits) {
1038 		struct sk_buff *p = cxgbi_sock_peek_wr(csk);
1039 
1040 		if (unlikely(!p)) {
1041 			pr_err("csk 0x%p,%u,0x%lx,%u, cr %u,%u+%u, empty.\n",
1042 				csk, csk->state, csk->flags, csk->tid, credits,
1043 				csk->wr_cred, csk->wr_una_cred);
1044 			break;
1045 		}
1046 
1047 		if (unlikely(credits < p->csum)) {
1048 			pr_warn("csk 0x%p,%u,0x%lx,%u, cr %u,%u+%u, < %u.\n",
1049 				csk, csk->state, csk->flags, csk->tid,
1050 				credits, csk->wr_cred, csk->wr_una_cred,
1051 				p->csum);
1052 			p->csum -= credits;
1053 			break;
1054 		} else {
1055 			cxgbi_sock_dequeue_wr(csk);
1056 			credits -= p->csum;
1057 			kfree_skb(p);
1058 		}
1059 	}
1060 
1061 	cxgbi_sock_check_wr_invariants(csk);
1062 
1063 	if (seq_chk) {
1064 		if (unlikely(before(snd_una, csk->snd_una))) {
1065 			pr_warn("csk 0x%p,%u,0x%lx,%u, snd_una %u/%u.",
1066 				csk, csk->state, csk->flags, csk->tid, snd_una,
1067 				csk->snd_una);
1068 			goto done;
1069 		}
1070 
1071 		if (csk->snd_una != snd_una) {
1072 			csk->snd_una = snd_una;
1073 			dst_confirm(csk->dst);
1074 		}
1075 	}
1076 
1077 	if (skb_queue_len(&csk->write_queue)) {
1078 		if (csk->cdev->csk_push_tx_frames(csk, 0))
1079 			cxgbi_conn_tx_open(csk);
1080 	} else
1081 		cxgbi_conn_tx_open(csk);
1082 done:
1083 	spin_unlock_bh(&csk->lock);
1084 }
1085 EXPORT_SYMBOL_GPL(cxgbi_sock_rcv_wr_ack);
1086 
1087 static unsigned int cxgbi_sock_find_best_mtu(struct cxgbi_sock *csk,
1088 					     unsigned short mtu)
1089 {
1090 	int i = 0;
1091 
1092 	while (i < csk->cdev->nmtus - 1 && csk->cdev->mtus[i + 1] <= mtu)
1093 		++i;
1094 
1095 	return i;
1096 }
1097 
1098 unsigned int cxgbi_sock_select_mss(struct cxgbi_sock *csk, unsigned int pmtu)
1099 {
1100 	unsigned int idx;
1101 	struct dst_entry *dst = csk->dst;
1102 
1103 	csk->advmss = dst_metric_advmss(dst);
1104 
1105 	if (csk->advmss > pmtu - 40)
1106 		csk->advmss = pmtu - 40;
1107 	if (csk->advmss < csk->cdev->mtus[0] - 40)
1108 		csk->advmss = csk->cdev->mtus[0] - 40;
1109 	idx = cxgbi_sock_find_best_mtu(csk, csk->advmss + 40);
1110 
1111 	return idx;
1112 }
1113 EXPORT_SYMBOL_GPL(cxgbi_sock_select_mss);
1114 
1115 void cxgbi_sock_skb_entail(struct cxgbi_sock *csk, struct sk_buff *skb)
1116 {
1117 	cxgbi_skcb_tcp_seq(skb) = csk->write_seq;
1118 	__skb_queue_tail(&csk->write_queue, skb);
1119 }
1120 EXPORT_SYMBOL_GPL(cxgbi_sock_skb_entail);
1121 
1122 void cxgbi_sock_purge_wr_queue(struct cxgbi_sock *csk)
1123 {
1124 	struct sk_buff *skb;
1125 
1126 	while ((skb = cxgbi_sock_dequeue_wr(csk)) != NULL)
1127 		kfree_skb(skb);
1128 }
1129 EXPORT_SYMBOL_GPL(cxgbi_sock_purge_wr_queue);
1130 
1131 void cxgbi_sock_check_wr_invariants(const struct cxgbi_sock *csk)
1132 {
1133 	int pending = cxgbi_sock_count_pending_wrs(csk);
1134 
1135 	if (unlikely(csk->wr_cred + pending != csk->wr_max_cred))
1136 		pr_err("csk 0x%p, tid %u, credit %u + %u != %u.\n",
1137 			csk, csk->tid, csk->wr_cred, pending, csk->wr_max_cred);
1138 }
1139 EXPORT_SYMBOL_GPL(cxgbi_sock_check_wr_invariants);
1140 
1141 static inline void
1142 scmd_get_params(struct scsi_cmnd *sc, struct scatterlist **sgl,
1143 		unsigned int *sgcnt, unsigned int *dlen,
1144 		unsigned int prot)
1145 {
1146 	struct scsi_data_buffer *sdb = prot ? scsi_prot(sc) : &sc->sdb;
1147 
1148 	*sgl = sdb->table.sgl;
1149 	*sgcnt = sdb->table.nents;
1150 	*dlen = sdb->length;
1151 	/* Caution: for protection sdb, sdb->length is invalid */
1152 }
1153 
1154 void cxgbi_ddp_set_one_ppod(struct cxgbi_pagepod *ppod,
1155 			    struct cxgbi_task_tag_info *ttinfo,
1156 			    struct scatterlist **sg_pp, unsigned int *sg_off)
1157 {
1158 	struct scatterlist *sg = sg_pp ? *sg_pp : NULL;
1159 	unsigned int offset = sg_off ? *sg_off : 0;
1160 	dma_addr_t addr = 0UL;
1161 	unsigned int len = 0;
1162 	int i;
1163 
1164 	memcpy(ppod, &ttinfo->hdr, sizeof(struct cxgbi_pagepod_hdr));
1165 
1166 	if (sg) {
1167 		addr = sg_dma_address(sg);
1168 		len = sg_dma_len(sg);
1169 	}
1170 
1171 	for (i = 0; i < PPOD_PAGES_MAX; i++) {
1172 		if (sg) {
1173 			ppod->addr[i] = cpu_to_be64(addr + offset);
1174 			offset += PAGE_SIZE;
1175 			if (offset == (len + sg->offset)) {
1176 				offset = 0;
1177 				sg = sg_next(sg);
1178 				if (sg) {
1179 					addr = sg_dma_address(sg);
1180 					len = sg_dma_len(sg);
1181 				}
1182 			}
1183 		} else {
1184 			ppod->addr[i] = 0ULL;
1185 		}
1186 	}
1187 
1188 	/*
1189 	 * the fifth address needs to be repeated in the next ppod, so do
1190 	 * not move sg
1191 	 */
1192 	if (sg_pp) {
1193 		*sg_pp = sg;
1194 		*sg_off = offset;
1195 	}
1196 
1197 	if (offset == len) {
1198 		offset = 0;
1199 		sg = sg_next(sg);
1200 		if (sg) {
1201 			addr = sg_dma_address(sg);
1202 			len = sg_dma_len(sg);
1203 		}
1204 	}
1205 	ppod->addr[i] = sg ? cpu_to_be64(addr + offset) : 0ULL;
1206 }
1207 EXPORT_SYMBOL_GPL(cxgbi_ddp_set_one_ppod);
1208 
1209 /*
1210  * APIs interacting with open-iscsi libraries
1211  */
1212 
1213 int cxgbi_ddp_ppm_setup(void **ppm_pp, struct cxgbi_device *cdev,
1214 			struct cxgbi_tag_format *tformat,
1215 			unsigned int iscsi_size, unsigned int llimit,
1216 			unsigned int start, unsigned int rsvd_factor,
1217 			unsigned int edram_start, unsigned int edram_size)
1218 {
1219 	int err = cxgbi_ppm_init(ppm_pp, cdev->ports[0], cdev->pdev,
1220 				cdev->lldev, tformat, iscsi_size, llimit, start,
1221 				rsvd_factor, edram_start, edram_size);
1222 
1223 	if (err >= 0) {
1224 		struct cxgbi_ppm *ppm = (struct cxgbi_ppm *)(*ppm_pp);
1225 
1226 		if (ppm->ppmax < 1024 ||
1227 		    ppm->tformat.pgsz_idx_dflt >= DDP_PGIDX_MAX)
1228 			cdev->flags |= CXGBI_FLAG_DDP_OFF;
1229 		err = 0;
1230 	} else {
1231 		cdev->flags |= CXGBI_FLAG_DDP_OFF;
1232 	}
1233 
1234 	return err;
1235 }
1236 EXPORT_SYMBOL_GPL(cxgbi_ddp_ppm_setup);
1237 
1238 static int cxgbi_ddp_sgl_check(struct scatterlist *sgl, int nents)
1239 {
1240 	int i;
1241 	int last_sgidx = nents - 1;
1242 	struct scatterlist *sg = sgl;
1243 
1244 	for (i = 0; i < nents; i++, sg = sg_next(sg)) {
1245 		unsigned int len = sg->length + sg->offset;
1246 
1247 		if ((sg->offset & 0x3) || (i && sg->offset) ||
1248 		    ((i != last_sgidx) && len != PAGE_SIZE)) {
1249 			log_debug(1 << CXGBI_DBG_DDP,
1250 				  "sg %u/%u, %u,%u, not aligned.\n",
1251 				  i, nents, sg->offset, sg->length);
1252 			goto err_out;
1253 		}
1254 	}
1255 	return 0;
1256 err_out:
1257 	return -EINVAL;
1258 }
1259 
1260 static int cxgbi_ddp_reserve(struct cxgbi_conn *cconn,
1261 			     struct cxgbi_task_data *tdata, u32 sw_tag,
1262 			     unsigned int xferlen)
1263 {
1264 	struct cxgbi_sock *csk = cconn->cep->csk;
1265 	struct cxgbi_device *cdev = csk->cdev;
1266 	struct cxgbi_ppm *ppm = cdev->cdev2ppm(cdev);
1267 	struct cxgbi_task_tag_info *ttinfo = &tdata->ttinfo;
1268 	struct scatterlist *sgl = ttinfo->sgl;
1269 	unsigned int sgcnt = ttinfo->nents;
1270 	unsigned int sg_offset = sgl->offset;
1271 	int err;
1272 
1273 	if (cdev->flags & CXGBI_FLAG_DDP_OFF) {
1274 		log_debug(1 << CXGBI_DBG_DDP,
1275 			  "cdev 0x%p DDP off.\n", cdev);
1276 		return -EINVAL;
1277 	}
1278 
1279 	if (!ppm || xferlen < DDP_THRESHOLD || !sgcnt ||
1280 	    ppm->tformat.pgsz_idx_dflt >= DDP_PGIDX_MAX) {
1281 		log_debug(1 << CXGBI_DBG_DDP,
1282 			  "ppm 0x%p, pgidx %u, xfer %u, sgcnt %u, NO ddp.\n",
1283 			  ppm, ppm ? ppm->tformat.pgsz_idx_dflt : DDP_PGIDX_MAX,
1284 			  xferlen, ttinfo->nents);
1285 		return -EINVAL;
1286 	}
1287 
1288 	/* make sure the buffer is suitable for ddp */
1289 	if (cxgbi_ddp_sgl_check(sgl, sgcnt) < 0)
1290 		return -EINVAL;
1291 
1292 	ttinfo->nr_pages = (xferlen + sgl->offset + (1 << PAGE_SHIFT) - 1) >>
1293 			    PAGE_SHIFT;
1294 
1295 	/*
1296 	 * the ddp tag will be used for the itt in the outgoing pdu,
1297 	 * the itt genrated by libiscsi is saved in the ppm and can be
1298 	 * retrieved via the ddp tag
1299 	 */
1300 	err = cxgbi_ppm_ppods_reserve(ppm, ttinfo->nr_pages, 0, &ttinfo->idx,
1301 				      &ttinfo->tag, (unsigned long)sw_tag);
1302 	if (err < 0) {
1303 		cconn->ddp_full++;
1304 		return err;
1305 	}
1306 	ttinfo->npods = err;
1307 
1308 	 /* setup dma from scsi command sgl */
1309 	sgl->offset = 0;
1310 	err = dma_map_sg(&ppm->pdev->dev, sgl, sgcnt, DMA_FROM_DEVICE);
1311 	sgl->offset = sg_offset;
1312 	if (err == 0) {
1313 		pr_info("%s: 0x%x, xfer %u, sgl %u dma mapping err.\n",
1314 			__func__, sw_tag, xferlen, sgcnt);
1315 		goto rel_ppods;
1316 	}
1317 	if (err != ttinfo->nr_pages) {
1318 		log_debug(1 << CXGBI_DBG_DDP,
1319 			  "%s: sw tag 0x%x, xfer %u, sgl %u, dma count %d.\n",
1320 			  __func__, sw_tag, xferlen, sgcnt, err);
1321 	}
1322 
1323 	ttinfo->flags |= CXGBI_PPOD_INFO_FLAG_MAPPED;
1324 	ttinfo->cid = csk->port_id;
1325 
1326 	cxgbi_ppm_make_ppod_hdr(ppm, ttinfo->tag, csk->tid, sgl->offset,
1327 				xferlen, &ttinfo->hdr);
1328 
1329 	if (cdev->flags & CXGBI_FLAG_USE_PPOD_OFLDQ) {
1330 		/* write ppod from xmit_pdu (of iscsi_scsi_command pdu) */
1331 		ttinfo->flags |= CXGBI_PPOD_INFO_FLAG_VALID;
1332 	} else {
1333 		/* write ppod from control queue now */
1334 		err = cdev->csk_ddp_set_map(ppm, csk, ttinfo);
1335 		if (err < 0)
1336 			goto rel_ppods;
1337 	}
1338 
1339 	return 0;
1340 
1341 rel_ppods:
1342 	cxgbi_ppm_ppod_release(ppm, ttinfo->idx);
1343 
1344 	if (ttinfo->flags & CXGBI_PPOD_INFO_FLAG_MAPPED) {
1345 		ttinfo->flags &= ~CXGBI_PPOD_INFO_FLAG_MAPPED;
1346 		dma_unmap_sg(&ppm->pdev->dev, sgl, sgcnt, DMA_FROM_DEVICE);
1347 	}
1348 	return -EINVAL;
1349 }
1350 
1351 static void task_release_itt(struct iscsi_task *task, itt_t hdr_itt)
1352 {
1353 	struct scsi_cmnd *sc = task->sc;
1354 	struct iscsi_tcp_conn *tcp_conn = task->conn->dd_data;
1355 	struct cxgbi_conn *cconn = tcp_conn->dd_data;
1356 	struct cxgbi_device *cdev = cconn->chba->cdev;
1357 	struct cxgbi_ppm *ppm = cdev->cdev2ppm(cdev);
1358 	u32 tag = ntohl((__force u32)hdr_itt);
1359 
1360 	log_debug(1 << CXGBI_DBG_DDP,
1361 		  "cdev 0x%p, task 0x%p, release tag 0x%x.\n",
1362 		  cdev, task, tag);
1363 	if (sc && sc->sc_data_direction == DMA_FROM_DEVICE &&
1364 	    cxgbi_ppm_is_ddp_tag(ppm, tag)) {
1365 		struct cxgbi_task_data *tdata = iscsi_task_cxgbi_data(task);
1366 		struct cxgbi_task_tag_info *ttinfo = &tdata->ttinfo;
1367 
1368 		if (!(cdev->flags & CXGBI_FLAG_USE_PPOD_OFLDQ))
1369 			cdev->csk_ddp_clear_map(cdev, ppm, ttinfo);
1370 		cxgbi_ppm_ppod_release(ppm, ttinfo->idx);
1371 		dma_unmap_sg(&ppm->pdev->dev, ttinfo->sgl, ttinfo->nents,
1372 			     DMA_FROM_DEVICE);
1373 	}
1374 }
1375 
1376 static inline u32 cxgbi_build_sw_tag(u32 idx, u32 age)
1377 {
1378 	/* assume idx and age both are < 0x7FFF (32767) */
1379 	return (idx << 16) | age;
1380 }
1381 
1382 static int task_reserve_itt(struct iscsi_task *task, itt_t *hdr_itt)
1383 {
1384 	struct scsi_cmnd *sc = task->sc;
1385 	struct iscsi_conn *conn = task->conn;
1386 	struct iscsi_session *sess = conn->session;
1387 	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1388 	struct cxgbi_conn *cconn = tcp_conn->dd_data;
1389 	struct cxgbi_device *cdev = cconn->chba->cdev;
1390 	struct cxgbi_ppm *ppm = cdev->cdev2ppm(cdev);
1391 	u32 sw_tag = cxgbi_build_sw_tag(task->itt, sess->age);
1392 	u32 tag = 0;
1393 	int err = -EINVAL;
1394 
1395 	if (sc && sc->sc_data_direction == DMA_FROM_DEVICE) {
1396 		struct cxgbi_task_data *tdata = iscsi_task_cxgbi_data(task);
1397 		struct cxgbi_task_tag_info *ttinfo = &tdata->ttinfo;
1398 
1399 		scmd_get_params(sc, &ttinfo->sgl, &ttinfo->nents,
1400 				&tdata->dlen, 0);
1401 		err = cxgbi_ddp_reserve(cconn, tdata, sw_tag, tdata->dlen);
1402 		if (!err)
1403 			tag = ttinfo->tag;
1404 		else
1405 			 log_debug(1 << CXGBI_DBG_DDP,
1406 				   "csk 0x%p, R task 0x%p, %u,%u, no ddp.\n",
1407 				   cconn->cep->csk, task, tdata->dlen,
1408 				   ttinfo->nents);
1409 	}
1410 
1411 	if (err < 0) {
1412 		err = cxgbi_ppm_make_non_ddp_tag(ppm, sw_tag, &tag);
1413 		if (err < 0)
1414 			return err;
1415 	}
1416 	/*  the itt need to sent in big-endian order */
1417 	*hdr_itt = (__force itt_t)htonl(tag);
1418 
1419 	log_debug(1 << CXGBI_DBG_DDP,
1420 		  "cdev 0x%p, task 0x%p, 0x%x(0x%x,0x%x)->0x%x/0x%x.\n",
1421 		  cdev, task, sw_tag, task->itt, sess->age, tag, *hdr_itt);
1422 	return 0;
1423 }
1424 
1425 void cxgbi_parse_pdu_itt(struct iscsi_conn *conn, itt_t itt, int *idx, int *age)
1426 {
1427 	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1428 	struct cxgbi_conn *cconn = tcp_conn->dd_data;
1429 	struct cxgbi_device *cdev = cconn->chba->cdev;
1430 	struct cxgbi_ppm *ppm = cdev->cdev2ppm(cdev);
1431 	u32 tag = ntohl((__force u32)itt);
1432 	u32 sw_bits;
1433 
1434 	if (ppm) {
1435 		if (cxgbi_ppm_is_ddp_tag(ppm, tag))
1436 			sw_bits = cxgbi_ppm_get_tag_caller_data(ppm, tag);
1437 		else
1438 			sw_bits = cxgbi_ppm_decode_non_ddp_tag(ppm, tag);
1439 	} else {
1440 		sw_bits = tag;
1441 	}
1442 
1443 	cxgbi_decode_sw_tag(sw_bits, idx, age);
1444 	log_debug(1 << CXGBI_DBG_DDP,
1445 		  "cdev 0x%p, tag 0x%x/0x%x, -> 0x%x(0x%x,0x%x).\n",
1446 		  cdev, tag, itt, sw_bits, idx ? *idx : 0xFFFFF,
1447 		  age ? *age : 0xFF);
1448 }
1449 EXPORT_SYMBOL_GPL(cxgbi_parse_pdu_itt);
1450 
1451 void cxgbi_conn_tx_open(struct cxgbi_sock *csk)
1452 {
1453 	struct iscsi_conn *conn = csk->user_data;
1454 
1455 	if (conn) {
1456 		log_debug(1 << CXGBI_DBG_SOCK,
1457 			"csk 0x%p, cid %d.\n", csk, conn->id);
1458 		iscsi_conn_queue_xmit(conn);
1459 	}
1460 }
1461 EXPORT_SYMBOL_GPL(cxgbi_conn_tx_open);
1462 
1463 /*
1464  * pdu receive, interact with libiscsi_tcp
1465  */
1466 static inline int read_pdu_skb(struct iscsi_conn *conn,
1467 			       struct sk_buff *skb,
1468 			       unsigned int offset,
1469 			       int offloaded)
1470 {
1471 	int status = 0;
1472 	int bytes_read;
1473 
1474 	bytes_read = iscsi_tcp_recv_skb(conn, skb, offset, offloaded, &status);
1475 	switch (status) {
1476 	case ISCSI_TCP_CONN_ERR:
1477 		pr_info("skb 0x%p, off %u, %d, TCP_ERR.\n",
1478 			  skb, offset, offloaded);
1479 		return -EIO;
1480 	case ISCSI_TCP_SUSPENDED:
1481 		log_debug(1 << CXGBI_DBG_PDU_RX,
1482 			"skb 0x%p, off %u, %d, TCP_SUSPEND, rc %d.\n",
1483 			skb, offset, offloaded, bytes_read);
1484 		/* no transfer - just have caller flush queue */
1485 		return bytes_read;
1486 	case ISCSI_TCP_SKB_DONE:
1487 		pr_info("skb 0x%p, off %u, %d, TCP_SKB_DONE.\n",
1488 			skb, offset, offloaded);
1489 		/*
1490 		 * pdus should always fit in the skb and we should get
1491 		 * segment done notifcation.
1492 		 */
1493 		iscsi_conn_printk(KERN_ERR, conn, "Invalid pdu or skb.");
1494 		return -EFAULT;
1495 	case ISCSI_TCP_SEGMENT_DONE:
1496 		log_debug(1 << CXGBI_DBG_PDU_RX,
1497 			"skb 0x%p, off %u, %d, TCP_SEG_DONE, rc %d.\n",
1498 			skb, offset, offloaded, bytes_read);
1499 		return bytes_read;
1500 	default:
1501 		pr_info("skb 0x%p, off %u, %d, invalid status %d.\n",
1502 			skb, offset, offloaded, status);
1503 		return -EINVAL;
1504 	}
1505 }
1506 
1507 static int
1508 skb_read_pdu_bhs(struct cxgbi_sock *csk, struct iscsi_conn *conn,
1509 		 struct sk_buff *skb)
1510 {
1511 	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1512 	int err;
1513 
1514 	log_debug(1 << CXGBI_DBG_PDU_RX,
1515 		"conn 0x%p, skb 0x%p, len %u, flag 0x%lx.\n",
1516 		conn, skb, skb->len, cxgbi_skcb_flags(skb));
1517 
1518 	if (!iscsi_tcp_recv_segment_is_hdr(tcp_conn)) {
1519 		pr_info("conn 0x%p, skb 0x%p, not hdr.\n", conn, skb);
1520 		iscsi_conn_failure(conn, ISCSI_ERR_PROTO);
1521 		return -EIO;
1522 	}
1523 
1524 	if (conn->hdrdgst_en &&
1525 	    cxgbi_skcb_test_flag(skb, SKCBF_RX_HCRC_ERR)) {
1526 		pr_info("conn 0x%p, skb 0x%p, hcrc.\n", conn, skb);
1527 		iscsi_conn_failure(conn, ISCSI_ERR_HDR_DGST);
1528 		return -EIO;
1529 	}
1530 
1531 	if (cxgbi_skcb_test_flag(skb, SKCBF_RX_ISCSI_COMPL) &&
1532 	    cxgbi_skcb_test_flag(skb, SKCBF_RX_DATA_DDPD)) {
1533 		/* If completion flag is set and data is directly
1534 		 * placed in to the host memory then update
1535 		 * task->exp_datasn to the datasn in completion
1536 		 * iSCSI hdr as T6 adapter generates completion only
1537 		 * for the last pdu of a sequence.
1538 		 */
1539 		itt_t itt = ((struct iscsi_data *)skb->data)->itt;
1540 		struct iscsi_task *task = iscsi_itt_to_ctask(conn, itt);
1541 		u32 data_sn = be32_to_cpu(((struct iscsi_data *)
1542 							skb->data)->datasn);
1543 		if (task && task->sc) {
1544 			struct iscsi_tcp_task *tcp_task = task->dd_data;
1545 
1546 			tcp_task->exp_datasn = data_sn;
1547 		}
1548 	}
1549 
1550 	err = read_pdu_skb(conn, skb, 0, 0);
1551 	if (likely(err >= 0)) {
1552 		struct iscsi_hdr *hdr = (struct iscsi_hdr *)skb->data;
1553 		u8 opcode = hdr->opcode & ISCSI_OPCODE_MASK;
1554 
1555 		if (unlikely(opcode == ISCSI_OP_LOGOUT_RSP))
1556 			cxgbi_sock_set_flag(csk, CTPF_LOGOUT_RSP_RCVD);
1557 	}
1558 
1559 	return err;
1560 }
1561 
1562 static int skb_read_pdu_data(struct iscsi_conn *conn, struct sk_buff *lskb,
1563 			     struct sk_buff *skb, unsigned int offset)
1564 {
1565 	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1566 	bool offloaded = 0;
1567 	int opcode = tcp_conn->in.hdr->opcode & ISCSI_OPCODE_MASK;
1568 
1569 	log_debug(1 << CXGBI_DBG_PDU_RX,
1570 		"conn 0x%p, skb 0x%p, len %u, flag 0x%lx.\n",
1571 		conn, skb, skb->len, cxgbi_skcb_flags(skb));
1572 
1573 	if (conn->datadgst_en &&
1574 	    cxgbi_skcb_test_flag(lskb, SKCBF_RX_DCRC_ERR)) {
1575 		pr_info("conn 0x%p, skb 0x%p, dcrc 0x%lx.\n",
1576 			conn, lskb, cxgbi_skcb_flags(lskb));
1577 		iscsi_conn_failure(conn, ISCSI_ERR_DATA_DGST);
1578 		return -EIO;
1579 	}
1580 
1581 	if (iscsi_tcp_recv_segment_is_hdr(tcp_conn))
1582 		return 0;
1583 
1584 	/* coalesced, add header digest length */
1585 	if (lskb == skb && conn->hdrdgst_en)
1586 		offset += ISCSI_DIGEST_SIZE;
1587 
1588 	if (cxgbi_skcb_test_flag(lskb, SKCBF_RX_DATA_DDPD))
1589 		offloaded = 1;
1590 
1591 	if (opcode == ISCSI_OP_SCSI_DATA_IN)
1592 		log_debug(1 << CXGBI_DBG_PDU_RX,
1593 			"skb 0x%p, op 0x%x, itt 0x%x, %u %s ddp'ed.\n",
1594 			skb, opcode, ntohl(tcp_conn->in.hdr->itt),
1595 			tcp_conn->in.datalen, offloaded ? "is" : "not");
1596 
1597 	return read_pdu_skb(conn, skb, offset, offloaded);
1598 }
1599 
1600 static void csk_return_rx_credits(struct cxgbi_sock *csk, int copied)
1601 {
1602 	struct cxgbi_device *cdev = csk->cdev;
1603 	int must_send;
1604 	u32 credits;
1605 
1606 	log_debug(1 << CXGBI_DBG_PDU_RX,
1607 		"csk 0x%p,%u,0x%lx,%u, seq %u, wup %u, thre %u, %u.\n",
1608 		csk, csk->state, csk->flags, csk->tid, csk->copied_seq,
1609 		csk->rcv_wup, cdev->rx_credit_thres,
1610 		csk->rcv_win);
1611 
1612 	if (!cdev->rx_credit_thres)
1613 		return;
1614 
1615 	if (csk->state != CTP_ESTABLISHED)
1616 		return;
1617 
1618 	credits = csk->copied_seq - csk->rcv_wup;
1619 	if (unlikely(!credits))
1620 		return;
1621 	must_send = credits + 16384 >= csk->rcv_win;
1622 	if (must_send || credits >= cdev->rx_credit_thres)
1623 		csk->rcv_wup += cdev->csk_send_rx_credits(csk, credits);
1624 }
1625 
1626 void cxgbi_conn_pdu_ready(struct cxgbi_sock *csk)
1627 {
1628 	struct cxgbi_device *cdev = csk->cdev;
1629 	struct iscsi_conn *conn = csk->user_data;
1630 	struct sk_buff *skb;
1631 	unsigned int read = 0;
1632 	int err = 0;
1633 
1634 	log_debug(1 << CXGBI_DBG_PDU_RX,
1635 		"csk 0x%p, conn 0x%p.\n", csk, conn);
1636 
1637 	if (unlikely(!conn || test_bit(ISCSI_CONN_FLAG_SUSPEND_RX, &conn->flags))) {
1638 		log_debug(1 << CXGBI_DBG_PDU_RX,
1639 			"csk 0x%p, conn 0x%p, id %d, conn flags 0x%lx!\n",
1640 			csk, conn, conn ? conn->id : 0xFF,
1641 			conn ? conn->flags : 0xFF);
1642 		return;
1643 	}
1644 
1645 	while (!err) {
1646 		skb = skb_peek(&csk->receive_queue);
1647 		if (!skb ||
1648 		    !(cxgbi_skcb_test_flag(skb, SKCBF_RX_STATUS))) {
1649 			if (skb)
1650 				log_debug(1 << CXGBI_DBG_PDU_RX,
1651 					"skb 0x%p, NOT ready 0x%lx.\n",
1652 					skb, cxgbi_skcb_flags(skb));
1653 			break;
1654 		}
1655 		__skb_unlink(skb, &csk->receive_queue);
1656 
1657 		read += cxgbi_skcb_rx_pdulen(skb);
1658 		log_debug(1 << CXGBI_DBG_PDU_RX,
1659 			"csk 0x%p, skb 0x%p,%u,f 0x%lx, pdu len %u.\n",
1660 			csk, skb, skb->len, cxgbi_skcb_flags(skb),
1661 			cxgbi_skcb_rx_pdulen(skb));
1662 
1663 		if (cxgbi_skcb_test_flag(skb, SKCBF_RX_COALESCED)) {
1664 			err = skb_read_pdu_bhs(csk, conn, skb);
1665 			if (err < 0) {
1666 				pr_err("coalesced bhs, csk 0x%p, skb 0x%p,%u, "
1667 					"f 0x%lx, plen %u.\n",
1668 					csk, skb, skb->len,
1669 					cxgbi_skcb_flags(skb),
1670 					cxgbi_skcb_rx_pdulen(skb));
1671 				goto skb_done;
1672 			}
1673 			err = skb_read_pdu_data(conn, skb, skb,
1674 						err + cdev->skb_rx_extra);
1675 			if (err < 0)
1676 				pr_err("coalesced data, csk 0x%p, skb 0x%p,%u, "
1677 					"f 0x%lx, plen %u.\n",
1678 					csk, skb, skb->len,
1679 					cxgbi_skcb_flags(skb),
1680 					cxgbi_skcb_rx_pdulen(skb));
1681 		} else {
1682 			err = skb_read_pdu_bhs(csk, conn, skb);
1683 			if (err < 0) {
1684 				pr_err("bhs, csk 0x%p, skb 0x%p,%u, "
1685 					"f 0x%lx, plen %u.\n",
1686 					csk, skb, skb->len,
1687 					cxgbi_skcb_flags(skb),
1688 					cxgbi_skcb_rx_pdulen(skb));
1689 				goto skb_done;
1690 			}
1691 
1692 			if (cxgbi_skcb_test_flag(skb, SKCBF_RX_DATA)) {
1693 				struct sk_buff *dskb;
1694 
1695 				dskb = skb_peek(&csk->receive_queue);
1696 				if (!dskb) {
1697 					pr_err("csk 0x%p, skb 0x%p,%u, f 0x%lx,"
1698 						" plen %u, NO data.\n",
1699 						csk, skb, skb->len,
1700 						cxgbi_skcb_flags(skb),
1701 						cxgbi_skcb_rx_pdulen(skb));
1702 					err = -EIO;
1703 					goto skb_done;
1704 				}
1705 				__skb_unlink(dskb, &csk->receive_queue);
1706 
1707 				err = skb_read_pdu_data(conn, skb, dskb, 0);
1708 				if (err < 0)
1709 					pr_err("data, csk 0x%p, skb 0x%p,%u, "
1710 						"f 0x%lx, plen %u, dskb 0x%p,"
1711 						"%u.\n",
1712 						csk, skb, skb->len,
1713 						cxgbi_skcb_flags(skb),
1714 						cxgbi_skcb_rx_pdulen(skb),
1715 						dskb, dskb->len);
1716 				__kfree_skb(dskb);
1717 			} else
1718 				err = skb_read_pdu_data(conn, skb, skb, 0);
1719 		}
1720 skb_done:
1721 		__kfree_skb(skb);
1722 
1723 		if (err < 0)
1724 			break;
1725 	}
1726 
1727 	log_debug(1 << CXGBI_DBG_PDU_RX, "csk 0x%p, read %u.\n", csk, read);
1728 	if (read) {
1729 		csk->copied_seq += read;
1730 		csk_return_rx_credits(csk, read);
1731 		conn->rxdata_octets += read;
1732 	}
1733 
1734 	if (err < 0) {
1735 		pr_info("csk 0x%p, 0x%p, rx failed %d, read %u.\n",
1736 			csk, conn, err, read);
1737 		iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1738 	}
1739 }
1740 EXPORT_SYMBOL_GPL(cxgbi_conn_pdu_ready);
1741 
1742 static int sgl_seek_offset(struct scatterlist *sgl, unsigned int sgcnt,
1743 				unsigned int offset, unsigned int *off,
1744 				struct scatterlist **sgp)
1745 {
1746 	int i;
1747 	struct scatterlist *sg;
1748 
1749 	for_each_sg(sgl, sg, sgcnt, i) {
1750 		if (offset < sg->length) {
1751 			*off = offset;
1752 			*sgp = sg;
1753 			return 0;
1754 		}
1755 		offset -= sg->length;
1756 	}
1757 	return -EFAULT;
1758 }
1759 
1760 static int
1761 sgl_read_to_frags(struct scatterlist *sg, unsigned int sgoffset,
1762 		  unsigned int dlen, struct page_frag *frags,
1763 		  int frag_max, u32 *dlimit)
1764 {
1765 	unsigned int datalen = dlen;
1766 	unsigned int sglen = sg->length - sgoffset;
1767 	struct page *page = sg_page(sg);
1768 	int i;
1769 
1770 	i = 0;
1771 	do {
1772 		unsigned int copy;
1773 
1774 		if (!sglen) {
1775 			sg = sg_next(sg);
1776 			if (!sg) {
1777 				pr_warn("sg %d NULL, len %u/%u.\n",
1778 					i, datalen, dlen);
1779 				return -EINVAL;
1780 			}
1781 			sgoffset = 0;
1782 			sglen = sg->length;
1783 			page = sg_page(sg);
1784 
1785 		}
1786 		copy = min(datalen, sglen);
1787 		if (i && page == frags[i - 1].page &&
1788 		    sgoffset + sg->offset ==
1789 			frags[i - 1].offset + frags[i - 1].size) {
1790 			frags[i - 1].size += copy;
1791 		} else {
1792 			if (i >= frag_max) {
1793 				pr_warn("too many pages %u, dlen %u.\n",
1794 					frag_max, dlen);
1795 				*dlimit = dlen - datalen;
1796 				return -EINVAL;
1797 			}
1798 
1799 			frags[i].page = page;
1800 			frags[i].offset = sg->offset + sgoffset;
1801 			frags[i].size = copy;
1802 			i++;
1803 		}
1804 		datalen -= copy;
1805 		sgoffset += copy;
1806 		sglen -= copy;
1807 	} while (datalen);
1808 
1809 	return i;
1810 }
1811 
1812 static void cxgbi_task_data_sgl_check(struct iscsi_task *task)
1813 {
1814 	struct scsi_cmnd *sc = task->sc;
1815 	struct cxgbi_task_data *tdata = iscsi_task_cxgbi_data(task);
1816 	struct scatterlist *sg, *sgl = NULL;
1817 	u32 sgcnt = 0;
1818 	int i;
1819 
1820 	tdata->flags = CXGBI_TASK_SGL_CHECKED;
1821 	if (!sc)
1822 		return;
1823 
1824 	scmd_get_params(sc, &sgl, &sgcnt, &tdata->dlen, 0);
1825 	if (!sgl || !sgcnt) {
1826 		tdata->flags |= CXGBI_TASK_SGL_COPY;
1827 		return;
1828 	}
1829 
1830 	for_each_sg(sgl, sg, sgcnt, i) {
1831 		if (page_count(sg_page(sg)) < 1) {
1832 			tdata->flags |= CXGBI_TASK_SGL_COPY;
1833 			return;
1834 		}
1835 	}
1836 }
1837 
1838 static int
1839 cxgbi_task_data_sgl_read(struct iscsi_task *task, u32 offset, u32 count,
1840 			 u32 *dlimit)
1841 {
1842 	struct scsi_cmnd *sc = task->sc;
1843 	struct cxgbi_task_data *tdata = iscsi_task_cxgbi_data(task);
1844 	struct scatterlist *sgl = NULL;
1845 	struct scatterlist *sg;
1846 	u32 dlen = 0;
1847 	u32 sgcnt;
1848 	int err;
1849 
1850 	if (!sc)
1851 		return 0;
1852 
1853 	scmd_get_params(sc, &sgl, &sgcnt, &dlen, 0);
1854 	if (!sgl || !sgcnt)
1855 		return 0;
1856 
1857 	err = sgl_seek_offset(sgl, sgcnt, offset, &tdata->sgoffset, &sg);
1858 	if (err < 0) {
1859 		pr_warn("tpdu max, sgl %u, bad offset %u/%u.\n",
1860 			sgcnt, offset, tdata->dlen);
1861 		return err;
1862 	}
1863 	err = sgl_read_to_frags(sg, tdata->sgoffset, count,
1864 				tdata->frags, MAX_SKB_FRAGS, dlimit);
1865 	if (err < 0) {
1866 		log_debug(1 << CXGBI_DBG_ISCSI,
1867 			  "sgl max limit, sgl %u, offset %u, %u/%u, dlimit %u.\n",
1868 			  sgcnt, offset, count, tdata->dlen, *dlimit);
1869 		return err;
1870 	}
1871 	tdata->offset = offset;
1872 	tdata->count = count;
1873 	tdata->nr_frags = err;
1874 	tdata->total_count = count;
1875 	tdata->total_offset = offset;
1876 
1877 	log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_PDU_TX,
1878 		  "%s: offset %u, count %u,\n"
1879 		  "err %u, total_count %u, total_offset %u\n",
1880 		  __func__, offset, count, err,  tdata->total_count, tdata->total_offset);
1881 
1882 	return 0;
1883 }
1884 
1885 int cxgbi_conn_alloc_pdu(struct iscsi_task *task, u8 op)
1886 {
1887 	struct iscsi_conn *conn = task->conn;
1888 	struct iscsi_session *session = task->conn->session;
1889 	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1890 	struct cxgbi_conn *cconn = tcp_conn->dd_data;
1891 	struct cxgbi_device *cdev = cconn->chba->cdev;
1892 	struct cxgbi_sock *csk = cconn->cep ? cconn->cep->csk : NULL;
1893 	struct iscsi_tcp_task *tcp_task = task->dd_data;
1894 	struct cxgbi_task_data *tdata = iscsi_task_cxgbi_data(task);
1895 	struct scsi_cmnd *sc = task->sc;
1896 	u32 headroom = SKB_TX_ISCSI_PDU_HEADER_MAX;
1897 	u32 max_txdata_len = conn->max_xmit_dlength;
1898 	u32 iso_tx_rsvd = 0, local_iso_info = 0;
1899 	u32 last_tdata_offset, last_tdata_count;
1900 	int err = 0;
1901 
1902 	if (!tcp_task) {
1903 		pr_err("task 0x%p, tcp_task 0x%p, tdata 0x%p.\n",
1904 		       task, tcp_task, tdata);
1905 		return -ENOMEM;
1906 	}
1907 	if (!csk) {
1908 		pr_err("task 0x%p, csk gone.\n", task);
1909 		return -EPIPE;
1910 	}
1911 
1912 	op &= ISCSI_OPCODE_MASK;
1913 
1914 	tcp_task->dd_data = tdata;
1915 	task->hdr = NULL;
1916 
1917 	last_tdata_count = tdata->count;
1918 	last_tdata_offset = tdata->offset;
1919 
1920 	if ((op == ISCSI_OP_SCSI_DATA_OUT) ||
1921 	    ((op == ISCSI_OP_SCSI_CMD) &&
1922 	     (sc->sc_data_direction == DMA_TO_DEVICE))) {
1923 		u32 remaining_data_tosend, dlimit = 0;
1924 		u32 max_pdu_size, max_num_pdu, num_pdu;
1925 		u32 count;
1926 
1927 		/* Preserve conn->max_xmit_dlength because it can get updated to
1928 		 * ISO data size.
1929 		 */
1930 		if (task->state == ISCSI_TASK_PENDING)
1931 			tdata->max_xmit_dlength = conn->max_xmit_dlength;
1932 
1933 		if (!tdata->offset)
1934 			cxgbi_task_data_sgl_check(task);
1935 
1936 		remaining_data_tosend =
1937 			tdata->dlen - tdata->offset - tdata->count;
1938 
1939 recalculate_sgl:
1940 		max_txdata_len = tdata->max_xmit_dlength;
1941 		log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_PDU_TX,
1942 			  "tdata->dlen %u, remaining to send %u "
1943 			  "conn->max_xmit_dlength %u, "
1944 			  "tdata->max_xmit_dlength %u\n",
1945 			  tdata->dlen, remaining_data_tosend,
1946 			  conn->max_xmit_dlength, tdata->max_xmit_dlength);
1947 
1948 		if (cdev->skb_iso_txhdr && !csk->disable_iso &&
1949 		    (remaining_data_tosend > tdata->max_xmit_dlength) &&
1950 		    !(remaining_data_tosend % 4)) {
1951 			u32 max_iso_data;
1952 
1953 			if ((op == ISCSI_OP_SCSI_CMD) &&
1954 			    session->initial_r2t_en)
1955 				goto no_iso;
1956 
1957 			max_pdu_size = tdata->max_xmit_dlength +
1958 				       ISCSI_PDU_NONPAYLOAD_LEN;
1959 			max_iso_data = rounddown(CXGBI_MAX_ISO_DATA_IN_SKB,
1960 						 csk->advmss);
1961 			max_num_pdu = max_iso_data / max_pdu_size;
1962 
1963 			num_pdu = (remaining_data_tosend +
1964 				   tdata->max_xmit_dlength - 1) /
1965 				  tdata->max_xmit_dlength;
1966 
1967 			if (num_pdu > max_num_pdu)
1968 				num_pdu = max_num_pdu;
1969 
1970 			conn->max_xmit_dlength = tdata->max_xmit_dlength * num_pdu;
1971 			max_txdata_len = conn->max_xmit_dlength;
1972 			iso_tx_rsvd = cdev->skb_iso_txhdr;
1973 			local_iso_info = sizeof(struct cxgbi_iso_info);
1974 
1975 			log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_PDU_TX,
1976 				  "max_pdu_size %u, max_num_pdu %u, "
1977 				  "max_txdata %u, num_pdu %u\n",
1978 				  max_pdu_size, max_num_pdu,
1979 				  max_txdata_len, num_pdu);
1980 		}
1981 no_iso:
1982 		count  = min_t(u32, max_txdata_len, remaining_data_tosend);
1983 		err = cxgbi_task_data_sgl_read(task,
1984 					       tdata->offset + tdata->count,
1985 					       count, &dlimit);
1986 		if (unlikely(err < 0)) {
1987 			log_debug(1 << CXGBI_DBG_ISCSI,
1988 				  "task 0x%p, tcp_task 0x%p, tdata 0x%p, "
1989 				  "sgl err %d, count %u, dlimit %u\n",
1990 				  task, tcp_task, tdata, err, count, dlimit);
1991 			if (dlimit) {
1992 				remaining_data_tosend =
1993 					rounddown(dlimit,
1994 						  tdata->max_xmit_dlength);
1995 				if (!remaining_data_tosend)
1996 					remaining_data_tosend = dlimit;
1997 
1998 				dlimit = 0;
1999 
2000 				conn->max_xmit_dlength = remaining_data_tosend;
2001 				goto recalculate_sgl;
2002 			}
2003 
2004 			pr_err("task 0x%p, tcp_task 0x%p, tdata 0x%p, "
2005 				"sgl err %d\n",
2006 				task, tcp_task, tdata, err);
2007 			goto ret_err;
2008 		}
2009 
2010 		if ((tdata->flags & CXGBI_TASK_SGL_COPY) ||
2011 		    (tdata->nr_frags > MAX_SKB_FRAGS))
2012 			headroom += conn->max_xmit_dlength;
2013 	}
2014 
2015 	tdata->skb = alloc_skb(local_iso_info + cdev->skb_tx_rsvd +
2016 			       iso_tx_rsvd + headroom, GFP_ATOMIC);
2017 	if (!tdata->skb) {
2018 		tdata->count = last_tdata_count;
2019 		tdata->offset = last_tdata_offset;
2020 		err = -ENOMEM;
2021 		goto ret_err;
2022 	}
2023 
2024 	skb_reserve(tdata->skb, local_iso_info + cdev->skb_tx_rsvd +
2025 		    iso_tx_rsvd);
2026 
2027 	if (task->sc) {
2028 		task->hdr = (struct iscsi_hdr *)tdata->skb->data;
2029 	} else {
2030 		task->hdr = kzalloc(SKB_TX_ISCSI_PDU_HEADER_MAX, GFP_ATOMIC);
2031 		if (!task->hdr) {
2032 			__kfree_skb(tdata->skb);
2033 			tdata->skb = NULL;
2034 			return -ENOMEM;
2035 		}
2036 	}
2037 
2038 	task->hdr_max = SKB_TX_ISCSI_PDU_HEADER_MAX;
2039 
2040 	if (iso_tx_rsvd)
2041 		cxgbi_skcb_set_flag(tdata->skb, SKCBF_TX_ISO);
2042 
2043 	/* data_out uses scsi_cmd's itt */
2044 	if (op != ISCSI_OP_SCSI_DATA_OUT)
2045 		task_reserve_itt(task, &task->hdr->itt);
2046 
2047 	log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_PDU_TX,
2048 		  "task 0x%p, op 0x%x, skb 0x%p,%u+%u/%u, itt 0x%x.\n",
2049 		  task, op, tdata->skb, cdev->skb_tx_rsvd, headroom,
2050 		  conn->max_xmit_dlength, be32_to_cpu(task->hdr->itt));
2051 
2052 	return 0;
2053 
2054 ret_err:
2055 	conn->max_xmit_dlength = tdata->max_xmit_dlength;
2056 	return err;
2057 }
2058 EXPORT_SYMBOL_GPL(cxgbi_conn_alloc_pdu);
2059 
2060 static int
2061 cxgbi_prep_iso_info(struct iscsi_task *task, struct sk_buff *skb,
2062 		    u32 count)
2063 {
2064 	struct cxgbi_iso_info *iso_info = (struct cxgbi_iso_info *)skb->head;
2065 	struct iscsi_r2t_info *r2t;
2066 	struct cxgbi_task_data *tdata = iscsi_task_cxgbi_data(task);
2067 	struct iscsi_conn *conn = task->conn;
2068 	struct iscsi_session *session = conn->session;
2069 	struct iscsi_tcp_task *tcp_task = task->dd_data;
2070 	u32 burst_size = 0, r2t_dlength = 0, dlength;
2071 	u32 max_pdu_len = tdata->max_xmit_dlength;
2072 	u32 segment_offset = 0;
2073 	u32 num_pdu;
2074 
2075 	if (unlikely(!cxgbi_skcb_test_flag(skb, SKCBF_TX_ISO)))
2076 		return 0;
2077 
2078 	memset(iso_info, 0, sizeof(struct cxgbi_iso_info));
2079 
2080 	if (task->hdr->opcode == ISCSI_OP_SCSI_CMD && session->imm_data_en) {
2081 		iso_info->flags |= CXGBI_ISO_INFO_IMM_ENABLE;
2082 		burst_size = count;
2083 	}
2084 
2085 	dlength = ntoh24(task->hdr->dlength);
2086 	dlength = min(dlength, max_pdu_len);
2087 	hton24(task->hdr->dlength, dlength);
2088 
2089 	num_pdu = (count + max_pdu_len - 1) / max_pdu_len;
2090 
2091 	if (iscsi_task_has_unsol_data(task))
2092 		r2t = &task->unsol_r2t;
2093 	else
2094 		r2t = tcp_task->r2t;
2095 
2096 	if (r2t) {
2097 		log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_PDU_TX,
2098 			  "count %u, tdata->count %u, num_pdu %u,"
2099 			  "task->hdr_len %u, r2t->data_length %u, r2t->sent %u\n",
2100 			  count, tdata->count, num_pdu, task->hdr_len,
2101 			  r2t->data_length, r2t->sent);
2102 
2103 		r2t_dlength = r2t->data_length - r2t->sent;
2104 		segment_offset = r2t->sent;
2105 		r2t->datasn += num_pdu - 1;
2106 	}
2107 
2108 	if (!r2t || !r2t->sent)
2109 		iso_info->flags |= CXGBI_ISO_INFO_FSLICE;
2110 
2111 	if (task->hdr->flags & ISCSI_FLAG_CMD_FINAL)
2112 		iso_info->flags |= CXGBI_ISO_INFO_LSLICE;
2113 
2114 	task->hdr->flags &= ~ISCSI_FLAG_CMD_FINAL;
2115 
2116 	iso_info->op = task->hdr->opcode;
2117 	iso_info->ahs = task->hdr->hlength;
2118 	iso_info->num_pdu = num_pdu;
2119 	iso_info->mpdu = max_pdu_len;
2120 	iso_info->burst_size = (burst_size + r2t_dlength) >> 2;
2121 	iso_info->len = count + task->hdr_len;
2122 	iso_info->segment_offset = segment_offset;
2123 
2124 	cxgbi_skcb_tx_iscsi_hdrlen(skb) = task->hdr_len;
2125 	return 0;
2126 }
2127 
2128 static inline void tx_skb_setmode(struct sk_buff *skb, int hcrc, int dcrc)
2129 {
2130 	if (hcrc || dcrc) {
2131 		u8 submode = 0;
2132 
2133 		if (hcrc)
2134 			submode |= 1;
2135 		if (dcrc)
2136 			submode |= 2;
2137 		cxgbi_skcb_tx_ulp_mode(skb) = (ULP2_MODE_ISCSI << 4) | submode;
2138 	} else
2139 		cxgbi_skcb_tx_ulp_mode(skb) = 0;
2140 }
2141 
2142 static struct page *rsvd_page;
2143 
2144 int cxgbi_conn_init_pdu(struct iscsi_task *task, unsigned int offset,
2145 			      unsigned int count)
2146 {
2147 	struct iscsi_conn *conn = task->conn;
2148 	struct iscsi_tcp_task *tcp_task = task->dd_data;
2149 	struct cxgbi_task_data *tdata = iscsi_task_cxgbi_data(task);
2150 	struct sk_buff *skb;
2151 	struct scsi_cmnd *sc = task->sc;
2152 	u32 expected_count, expected_offset;
2153 	u32 datalen = count, dlimit = 0;
2154 	u32 i, padlen = iscsi_padding(count);
2155 	struct page *pg;
2156 	int err;
2157 
2158 	if (!tcp_task || (tcp_task->dd_data != tdata)) {
2159 		pr_err("task 0x%p,0x%p, tcp_task 0x%p, tdata 0x%p/0x%p.\n",
2160 		       task, task->sc, tcp_task,
2161 		       tcp_task ? tcp_task->dd_data : NULL, tdata);
2162 		return -EINVAL;
2163 	}
2164 	skb = tdata->skb;
2165 
2166 	log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_PDU_TX,
2167 		  "task 0x%p,0x%p, skb 0x%p, 0x%x,0x%x,0x%x, %u+%u.\n",
2168 		  task, task->sc, skb, (*skb->data) & ISCSI_OPCODE_MASK,
2169 		  be32_to_cpu(task->cmdsn), be32_to_cpu(task->hdr->itt), offset, count);
2170 
2171 	skb_put(skb, task->hdr_len);
2172 	tx_skb_setmode(skb, conn->hdrdgst_en, datalen ? conn->datadgst_en : 0);
2173 	if (!count) {
2174 		tdata->count = count;
2175 		tdata->offset = offset;
2176 		tdata->nr_frags = 0;
2177 		tdata->total_offset = 0;
2178 		tdata->total_count = 0;
2179 		if (tdata->max_xmit_dlength)
2180 			conn->max_xmit_dlength = tdata->max_xmit_dlength;
2181 		cxgbi_skcb_clear_flag(skb, SKCBF_TX_ISO);
2182 		return 0;
2183 	}
2184 
2185 	log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_PDU_TX,
2186 		  "data->total_count %u, tdata->total_offset %u\n",
2187 		  tdata->total_count, tdata->total_offset);
2188 
2189 	expected_count = tdata->total_count;
2190 	expected_offset = tdata->total_offset;
2191 
2192 	if ((count != expected_count) ||
2193 	    (offset != expected_offset)) {
2194 		err = cxgbi_task_data_sgl_read(task, offset, count, &dlimit);
2195 		if (err < 0) {
2196 			pr_err("task 0x%p,0x%p, tcp_task 0x%p, tdata 0x%p/0x%p "
2197 			       "dlimit %u, sgl err %d.\n", task, task->sc,
2198 			       tcp_task, tcp_task ? tcp_task->dd_data : NULL,
2199 			       tdata, dlimit, err);
2200 			return err;
2201 		}
2202 	}
2203 
2204 	/* Restore original value of conn->max_xmit_dlength because
2205 	 * it can get updated to ISO data size.
2206 	 */
2207 	conn->max_xmit_dlength = tdata->max_xmit_dlength;
2208 
2209 	if (sc) {
2210 		struct page_frag *frag = tdata->frags;
2211 
2212 		if ((tdata->flags & CXGBI_TASK_SGL_COPY) ||
2213 		    (tdata->nr_frags > MAX_SKB_FRAGS) ||
2214 		    (padlen && (tdata->nr_frags ==
2215 					MAX_SKB_FRAGS))) {
2216 			char *dst = skb->data + task->hdr_len;
2217 
2218 			/* data fits in the skb's headroom */
2219 			for (i = 0; i < tdata->nr_frags; i++, frag++) {
2220 				char *src = kmap_atomic(frag->page);
2221 
2222 				memcpy(dst, src + frag->offset, frag->size);
2223 				dst += frag->size;
2224 				kunmap_atomic(src);
2225 			}
2226 
2227 			if (padlen) {
2228 				memset(dst, 0, padlen);
2229 				padlen = 0;
2230 			}
2231 			skb_put(skb, count + padlen);
2232 		} else {
2233 			for (i = 0; i < tdata->nr_frags; i++, frag++) {
2234 				get_page(frag->page);
2235 				skb_fill_page_desc(skb, i, frag->page,
2236 						   frag->offset, frag->size);
2237 			}
2238 
2239 			skb->len += count;
2240 			skb->data_len += count;
2241 			skb->truesize += count;
2242 		}
2243 	} else {
2244 		pg = virt_to_head_page(task->data);
2245 		get_page(pg);
2246 		skb_fill_page_desc(skb, 0, pg,
2247 				   task->data - (char *)page_address(pg),
2248 				   count);
2249 		skb->len += count;
2250 		skb->data_len += count;
2251 		skb->truesize += count;
2252 	}
2253 
2254 	if (padlen) {
2255 		get_page(rsvd_page);
2256 		skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags,
2257 				   rsvd_page, 0, padlen);
2258 
2259 		skb->data_len += padlen;
2260 		skb->truesize += padlen;
2261 		skb->len += padlen;
2262 	}
2263 
2264 	if (likely(count > tdata->max_xmit_dlength))
2265 		cxgbi_prep_iso_info(task, skb, count);
2266 	else
2267 		cxgbi_skcb_clear_flag(skb, SKCBF_TX_ISO);
2268 
2269 	return 0;
2270 }
2271 EXPORT_SYMBOL_GPL(cxgbi_conn_init_pdu);
2272 
2273 static int cxgbi_sock_tx_queue_up(struct cxgbi_sock *csk, struct sk_buff *skb)
2274 {
2275 	struct cxgbi_device *cdev = csk->cdev;
2276 	struct cxgbi_iso_info *iso_cpl;
2277 	u32 frags = skb_shinfo(skb)->nr_frags;
2278 	u32 extra_len, num_pdu, hdr_len;
2279 	u32 iso_tx_rsvd = 0;
2280 
2281 	if (csk->state != CTP_ESTABLISHED) {
2282 		log_debug(1 << CXGBI_DBG_PDU_TX,
2283 			  "csk 0x%p,%u,0x%lx,%u, EAGAIN.\n",
2284 			  csk, csk->state, csk->flags, csk->tid);
2285 		return -EPIPE;
2286 	}
2287 
2288 	if (csk->err) {
2289 		log_debug(1 << CXGBI_DBG_PDU_TX,
2290 			  "csk 0x%p,%u,0x%lx,%u, EPIPE %d.\n",
2291 			  csk, csk->state, csk->flags, csk->tid, csk->err);
2292 		return -EPIPE;
2293 	}
2294 
2295 	if ((cdev->flags & CXGBI_FLAG_DEV_T3) &&
2296 	    before((csk->snd_win + csk->snd_una), csk->write_seq)) {
2297 		log_debug(1 << CXGBI_DBG_PDU_TX,
2298 			  "csk 0x%p,%u,0x%lx,%u, FULL %u-%u >= %u.\n",
2299 			  csk, csk->state, csk->flags, csk->tid, csk->write_seq,
2300 			  csk->snd_una, csk->snd_win);
2301 		return -ENOBUFS;
2302 	}
2303 
2304 	if (cxgbi_skcb_test_flag(skb, SKCBF_TX_ISO))
2305 		iso_tx_rsvd = cdev->skb_iso_txhdr;
2306 
2307 	if (unlikely(skb_headroom(skb) < (cdev->skb_tx_rsvd + iso_tx_rsvd))) {
2308 		pr_err("csk 0x%p, skb head %u < %u.\n",
2309 		       csk, skb_headroom(skb), cdev->skb_tx_rsvd);
2310 		return -EINVAL;
2311 	}
2312 
2313 	if (skb->len != skb->data_len)
2314 		frags++;
2315 
2316 	if (frags >= SKB_WR_LIST_SIZE) {
2317 		pr_err("csk 0x%p, frags %u, %u,%u >%u.\n",
2318 		       csk, skb_shinfo(skb)->nr_frags, skb->len,
2319 		       skb->data_len, (unsigned int)SKB_WR_LIST_SIZE);
2320 		return -EINVAL;
2321 	}
2322 
2323 	cxgbi_skcb_set_flag(skb, SKCBF_TX_NEED_HDR);
2324 	skb_reset_transport_header(skb);
2325 	cxgbi_sock_skb_entail(csk, skb);
2326 
2327 	extra_len = cxgbi_ulp_extra_len(cxgbi_skcb_tx_ulp_mode(skb));
2328 
2329 	if (likely(cxgbi_skcb_test_flag(skb, SKCBF_TX_ISO))) {
2330 		iso_cpl = (struct cxgbi_iso_info *)skb->head;
2331 		num_pdu = iso_cpl->num_pdu;
2332 		hdr_len = cxgbi_skcb_tx_iscsi_hdrlen(skb);
2333 		extra_len = (cxgbi_ulp_extra_len(cxgbi_skcb_tx_ulp_mode(skb)) *
2334 			     num_pdu) +	(hdr_len * (num_pdu - 1));
2335 	}
2336 
2337 	csk->write_seq += (skb->len + extra_len);
2338 
2339 	return 0;
2340 }
2341 
2342 static int cxgbi_sock_send_skb(struct cxgbi_sock *csk, struct sk_buff *skb)
2343 {
2344 	struct cxgbi_device *cdev = csk->cdev;
2345 	int len = skb->len;
2346 	int err;
2347 
2348 	spin_lock_bh(&csk->lock);
2349 	err = cxgbi_sock_tx_queue_up(csk, skb);
2350 	if (err < 0) {
2351 		spin_unlock_bh(&csk->lock);
2352 		return err;
2353 	}
2354 
2355 	if (likely(skb_queue_len(&csk->write_queue)))
2356 		cdev->csk_push_tx_frames(csk, 0);
2357 	spin_unlock_bh(&csk->lock);
2358 	return len;
2359 }
2360 
2361 int cxgbi_conn_xmit_pdu(struct iscsi_task *task)
2362 {
2363 	struct iscsi_tcp_conn *tcp_conn = task->conn->dd_data;
2364 	struct cxgbi_conn *cconn = tcp_conn->dd_data;
2365 	struct iscsi_tcp_task *tcp_task = task->dd_data;
2366 	struct cxgbi_task_data *tdata = iscsi_task_cxgbi_data(task);
2367 	struct cxgbi_task_tag_info *ttinfo = &tdata->ttinfo;
2368 	struct sk_buff *skb;
2369 	struct cxgbi_sock *csk = NULL;
2370 	u32 pdulen = 0;
2371 	u32 datalen;
2372 	int err;
2373 
2374 	if (!tcp_task || (tcp_task->dd_data != tdata)) {
2375 		pr_err("task 0x%p,0x%p, tcp_task 0x%p, tdata 0x%p/0x%p.\n",
2376 		       task, task->sc, tcp_task,
2377 		       tcp_task ? tcp_task->dd_data : NULL, tdata);
2378 		return -EINVAL;
2379 	}
2380 
2381 	skb = tdata->skb;
2382 	if (!skb) {
2383 		log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_PDU_TX,
2384 			  "task 0x%p, skb NULL.\n", task);
2385 		return 0;
2386 	}
2387 
2388 	if (cconn && cconn->cep)
2389 		csk = cconn->cep->csk;
2390 
2391 	if (!csk) {
2392 		log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_PDU_TX,
2393 			  "task 0x%p, csk gone.\n", task);
2394 		return -EPIPE;
2395 	}
2396 
2397 	tdata->skb = NULL;
2398 	datalen = skb->data_len;
2399 
2400 	/* write ppod first if using ofldq to write ppod */
2401 	if (ttinfo->flags & CXGBI_PPOD_INFO_FLAG_VALID) {
2402 		struct cxgbi_ppm *ppm = csk->cdev->cdev2ppm(csk->cdev);
2403 
2404 		ttinfo->flags &= ~CXGBI_PPOD_INFO_FLAG_VALID;
2405 		if (csk->cdev->csk_ddp_set_map(ppm, csk, ttinfo) < 0)
2406 			pr_err("task 0x%p, ppod writing using ofldq failed.\n",
2407 			       task);
2408 			/* continue. Let fl get the data */
2409 	}
2410 
2411 	if (!task->sc)
2412 		memcpy(skb->data, task->hdr, SKB_TX_ISCSI_PDU_HEADER_MAX);
2413 
2414 	err = cxgbi_sock_send_skb(csk, skb);
2415 	if (err > 0) {
2416 		pdulen += err;
2417 
2418 		log_debug(1 << CXGBI_DBG_PDU_TX, "task 0x%p,0x%p, rv %d.\n",
2419 			  task, task->sc, err);
2420 
2421 		if (task->conn->hdrdgst_en)
2422 			pdulen += ISCSI_DIGEST_SIZE;
2423 
2424 		if (datalen && task->conn->datadgst_en)
2425 			pdulen += ISCSI_DIGEST_SIZE;
2426 
2427 		task->conn->txdata_octets += pdulen;
2428 
2429 		if (unlikely(cxgbi_is_iso_config(csk) && cxgbi_is_iso_disabled(csk))) {
2430 			if (time_after(jiffies, csk->prev_iso_ts + HZ)) {
2431 				csk->disable_iso = false;
2432 				csk->prev_iso_ts = 0;
2433 				log_debug(1 << CXGBI_DBG_PDU_TX,
2434 					  "enable iso: csk 0x%p\n", csk);
2435 			}
2436 		}
2437 
2438 		return 0;
2439 	}
2440 
2441 	if (err == -EAGAIN || err == -ENOBUFS) {
2442 		log_debug(1 << CXGBI_DBG_PDU_TX,
2443 			  "task 0x%p, skb 0x%p, len %u/%u, %d EAGAIN.\n",
2444 			  task, skb, skb->len, skb->data_len, err);
2445 		/* reset skb to send when we are called again */
2446 		tdata->skb = skb;
2447 
2448 		if (cxgbi_is_iso_config(csk) && !cxgbi_is_iso_disabled(csk) &&
2449 		    (csk->no_tx_credits++ >= 2)) {
2450 			csk->disable_iso = true;
2451 			csk->prev_iso_ts = jiffies;
2452 			log_debug(1 << CXGBI_DBG_PDU_TX,
2453 				  "disable iso:csk 0x%p, ts:%lu\n",
2454 				  csk, csk->prev_iso_ts);
2455 		}
2456 
2457 		return err;
2458 	}
2459 
2460 	log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_PDU_TX,
2461 		  "itt 0x%x, skb 0x%p, len %u/%u, xmit err %d.\n",
2462 		  task->itt, skb, skb->len, skb->data_len, err);
2463 	__kfree_skb(skb);
2464 	iscsi_conn_printk(KERN_ERR, task->conn, "xmit err %d.\n", err);
2465 	iscsi_conn_failure(task->conn, ISCSI_ERR_XMIT_FAILED);
2466 	return err;
2467 }
2468 EXPORT_SYMBOL_GPL(cxgbi_conn_xmit_pdu);
2469 
2470 void cxgbi_cleanup_task(struct iscsi_task *task)
2471 {
2472 	struct iscsi_tcp_task *tcp_task = task->dd_data;
2473 	struct cxgbi_task_data *tdata = iscsi_task_cxgbi_data(task);
2474 
2475 	if (!tcp_task || (tcp_task->dd_data != tdata)) {
2476 		pr_info("task 0x%p,0x%p, tcp_task 0x%p, tdata 0x%p/0x%p.\n",
2477 			task, task->sc, tcp_task,
2478 			tcp_task ? tcp_task->dd_data : NULL, tdata);
2479 		return;
2480 	}
2481 
2482 	log_debug(1 << CXGBI_DBG_ISCSI,
2483 		"task 0x%p, skb 0x%p, itt 0x%x.\n",
2484 		task, tdata->skb, task->hdr_itt);
2485 
2486 	tcp_task->dd_data = NULL;
2487 
2488 	if (!task->sc)
2489 		kfree(task->hdr);
2490 	task->hdr = NULL;
2491 
2492 	/*  never reached the xmit task callout */
2493 	if (tdata->skb) {
2494 		__kfree_skb(tdata->skb);
2495 		tdata->skb = NULL;
2496 	}
2497 
2498 	task_release_itt(task, task->hdr_itt);
2499 	memset(tdata, 0, sizeof(*tdata));
2500 
2501 	iscsi_tcp_cleanup_task(task);
2502 }
2503 EXPORT_SYMBOL_GPL(cxgbi_cleanup_task);
2504 
2505 void cxgbi_get_conn_stats(struct iscsi_cls_conn *cls_conn,
2506 				struct iscsi_stats *stats)
2507 {
2508 	struct iscsi_conn *conn = cls_conn->dd_data;
2509 
2510 	stats->txdata_octets = conn->txdata_octets;
2511 	stats->rxdata_octets = conn->rxdata_octets;
2512 	stats->scsicmd_pdus = conn->scsicmd_pdus_cnt;
2513 	stats->dataout_pdus = conn->dataout_pdus_cnt;
2514 	stats->scsirsp_pdus = conn->scsirsp_pdus_cnt;
2515 	stats->datain_pdus = conn->datain_pdus_cnt;
2516 	stats->r2t_pdus = conn->r2t_pdus_cnt;
2517 	stats->tmfcmd_pdus = conn->tmfcmd_pdus_cnt;
2518 	stats->tmfrsp_pdus = conn->tmfrsp_pdus_cnt;
2519 	stats->digest_err = 0;
2520 	stats->timeout_err = 0;
2521 	stats->custom_length = 1;
2522 	strcpy(stats->custom[0].desc, "eh_abort_cnt");
2523 	stats->custom[0].value = conn->eh_abort_cnt;
2524 }
2525 EXPORT_SYMBOL_GPL(cxgbi_get_conn_stats);
2526 
2527 static int cxgbi_conn_max_xmit_dlength(struct iscsi_conn *conn)
2528 {
2529 	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
2530 	struct cxgbi_conn *cconn = tcp_conn->dd_data;
2531 	struct cxgbi_device *cdev = cconn->chba->cdev;
2532 	unsigned int headroom = SKB_MAX_HEAD(cdev->skb_tx_rsvd);
2533 	unsigned int max_def = 512 * MAX_SKB_FRAGS;
2534 	unsigned int max = max(max_def, headroom);
2535 
2536 	max = min(cconn->chba->cdev->tx_max_size, max);
2537 	if (conn->max_xmit_dlength)
2538 		conn->max_xmit_dlength = min(conn->max_xmit_dlength, max);
2539 	else
2540 		conn->max_xmit_dlength = max;
2541 	cxgbi_align_pdu_size(conn->max_xmit_dlength);
2542 
2543 	return 0;
2544 }
2545 
2546 static int cxgbi_conn_max_recv_dlength(struct iscsi_conn *conn)
2547 {
2548 	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
2549 	struct cxgbi_conn *cconn = tcp_conn->dd_data;
2550 	unsigned int max = cconn->chba->cdev->rx_max_size;
2551 
2552 	cxgbi_align_pdu_size(max);
2553 
2554 	if (conn->max_recv_dlength) {
2555 		if (conn->max_recv_dlength > max) {
2556 			pr_err("MaxRecvDataSegmentLength %u > %u.\n",
2557 				conn->max_recv_dlength, max);
2558 			return -EINVAL;
2559 		}
2560 		conn->max_recv_dlength = min(conn->max_recv_dlength, max);
2561 		cxgbi_align_pdu_size(conn->max_recv_dlength);
2562 	} else
2563 		conn->max_recv_dlength = max;
2564 
2565 	return 0;
2566 }
2567 
2568 int cxgbi_set_conn_param(struct iscsi_cls_conn *cls_conn,
2569 			enum iscsi_param param, char *buf, int buflen)
2570 {
2571 	struct iscsi_conn *conn = cls_conn->dd_data;
2572 	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
2573 	struct cxgbi_conn *cconn = tcp_conn->dd_data;
2574 	struct cxgbi_sock *csk = cconn->cep->csk;
2575 	int err;
2576 
2577 	log_debug(1 << CXGBI_DBG_ISCSI,
2578 		"cls_conn 0x%p, param %d, buf(%d) %s.\n",
2579 		cls_conn, param, buflen, buf);
2580 
2581 	switch (param) {
2582 	case ISCSI_PARAM_HDRDGST_EN:
2583 		err = iscsi_set_param(cls_conn, param, buf, buflen);
2584 		if (!err && conn->hdrdgst_en)
2585 			err = csk->cdev->csk_ddp_setup_digest(csk, csk->tid,
2586 							conn->hdrdgst_en,
2587 							conn->datadgst_en);
2588 		break;
2589 	case ISCSI_PARAM_DATADGST_EN:
2590 		err = iscsi_set_param(cls_conn, param, buf, buflen);
2591 		if (!err && conn->datadgst_en)
2592 			err = csk->cdev->csk_ddp_setup_digest(csk, csk->tid,
2593 							conn->hdrdgst_en,
2594 							conn->datadgst_en);
2595 		break;
2596 	case ISCSI_PARAM_MAX_R2T:
2597 		return iscsi_tcp_set_max_r2t(conn, buf);
2598 	case ISCSI_PARAM_MAX_RECV_DLENGTH:
2599 		err = iscsi_set_param(cls_conn, param, buf, buflen);
2600 		if (!err)
2601 			err = cxgbi_conn_max_recv_dlength(conn);
2602 		break;
2603 	case ISCSI_PARAM_MAX_XMIT_DLENGTH:
2604 		err = iscsi_set_param(cls_conn, param, buf, buflen);
2605 		if (!err)
2606 			err = cxgbi_conn_max_xmit_dlength(conn);
2607 		break;
2608 	default:
2609 		return iscsi_set_param(cls_conn, param, buf, buflen);
2610 	}
2611 	return err;
2612 }
2613 EXPORT_SYMBOL_GPL(cxgbi_set_conn_param);
2614 
2615 int cxgbi_get_ep_param(struct iscsi_endpoint *ep, enum iscsi_param param,
2616 		       char *buf)
2617 {
2618 	struct cxgbi_endpoint *cep = ep->dd_data;
2619 	struct cxgbi_sock *csk;
2620 
2621 	log_debug(1 << CXGBI_DBG_ISCSI,
2622 		"cls_conn 0x%p, param %d.\n", ep, param);
2623 
2624 	switch (param) {
2625 	case ISCSI_PARAM_CONN_PORT:
2626 	case ISCSI_PARAM_CONN_ADDRESS:
2627 		if (!cep)
2628 			return -ENOTCONN;
2629 
2630 		csk = cep->csk;
2631 		if (!csk)
2632 			return -ENOTCONN;
2633 
2634 		return iscsi_conn_get_addr_param((struct sockaddr_storage *)
2635 						 &csk->daddr, param, buf);
2636 	default:
2637 		break;
2638 	}
2639 	return -ENOSYS;
2640 }
2641 EXPORT_SYMBOL_GPL(cxgbi_get_ep_param);
2642 
2643 struct iscsi_cls_conn *
2644 cxgbi_create_conn(struct iscsi_cls_session *cls_session, u32 cid)
2645 {
2646 	struct iscsi_cls_conn *cls_conn;
2647 	struct iscsi_conn *conn;
2648 	struct iscsi_tcp_conn *tcp_conn;
2649 	struct cxgbi_conn *cconn;
2650 
2651 	cls_conn = iscsi_tcp_conn_setup(cls_session, sizeof(*cconn), cid);
2652 	if (!cls_conn)
2653 		return NULL;
2654 
2655 	conn = cls_conn->dd_data;
2656 	tcp_conn = conn->dd_data;
2657 	cconn = tcp_conn->dd_data;
2658 	cconn->iconn = conn;
2659 
2660 	log_debug(1 << CXGBI_DBG_ISCSI,
2661 		"cid %u(0x%x), cls 0x%p,0x%p, conn 0x%p,0x%p,0x%p.\n",
2662 		cid, cid, cls_session, cls_conn, conn, tcp_conn, cconn);
2663 
2664 	return cls_conn;
2665 }
2666 EXPORT_SYMBOL_GPL(cxgbi_create_conn);
2667 
2668 int cxgbi_bind_conn(struct iscsi_cls_session *cls_session,
2669 				struct iscsi_cls_conn *cls_conn,
2670 				u64 transport_eph, int is_leading)
2671 {
2672 	struct iscsi_conn *conn = cls_conn->dd_data;
2673 	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
2674 	struct cxgbi_conn *cconn = tcp_conn->dd_data;
2675 	struct cxgbi_ppm *ppm;
2676 	struct iscsi_endpoint *ep;
2677 	struct cxgbi_endpoint *cep;
2678 	struct cxgbi_sock *csk;
2679 	int err;
2680 
2681 	ep = iscsi_lookup_endpoint(transport_eph);
2682 	if (!ep)
2683 		return -EINVAL;
2684 
2685 	/*  setup ddp pagesize */
2686 	cep = ep->dd_data;
2687 	csk = cep->csk;
2688 
2689 	ppm = csk->cdev->cdev2ppm(csk->cdev);
2690 	err = csk->cdev->csk_ddp_setup_pgidx(csk, csk->tid,
2691 					     ppm->tformat.pgsz_idx_dflt);
2692 	if (err < 0)
2693 		goto put_ep;
2694 
2695 	err = iscsi_conn_bind(cls_session, cls_conn, is_leading);
2696 	if (err) {
2697 		err = -EINVAL;
2698 		goto put_ep;
2699 	}
2700 
2701 	/*  calculate the tag idx bits needed for this conn based on cmds_max */
2702 	cconn->task_idx_bits = (__ilog2_u32(conn->session->cmds_max - 1)) + 1;
2703 
2704 	write_lock_bh(&csk->callback_lock);
2705 	csk->user_data = conn;
2706 	cconn->chba = cep->chba;
2707 	cconn->cep = cep;
2708 	cep->cconn = cconn;
2709 	write_unlock_bh(&csk->callback_lock);
2710 
2711 	cxgbi_conn_max_xmit_dlength(conn);
2712 	cxgbi_conn_max_recv_dlength(conn);
2713 
2714 	log_debug(1 << CXGBI_DBG_ISCSI,
2715 		"cls 0x%p,0x%p, ep 0x%p, cconn 0x%p, csk 0x%p.\n",
2716 		cls_session, cls_conn, ep, cconn, csk);
2717 	/*  init recv engine */
2718 	iscsi_tcp_hdr_recv_prep(tcp_conn);
2719 
2720 put_ep:
2721 	iscsi_put_endpoint(ep);
2722 	return err;
2723 }
2724 EXPORT_SYMBOL_GPL(cxgbi_bind_conn);
2725 
2726 struct iscsi_cls_session *cxgbi_create_session(struct iscsi_endpoint *ep,
2727 						u16 cmds_max, u16 qdepth,
2728 						u32 initial_cmdsn)
2729 {
2730 	struct cxgbi_endpoint *cep;
2731 	struct cxgbi_hba *chba;
2732 	struct Scsi_Host *shost;
2733 	struct iscsi_cls_session *cls_session;
2734 	struct iscsi_session *session;
2735 
2736 	if (!ep) {
2737 		pr_err("missing endpoint.\n");
2738 		return NULL;
2739 	}
2740 
2741 	cep = ep->dd_data;
2742 	chba = cep->chba;
2743 	shost = chba->shost;
2744 
2745 	BUG_ON(chba != iscsi_host_priv(shost));
2746 
2747 	cls_session = iscsi_session_setup(chba->cdev->itp, shost,
2748 					cmds_max, 0,
2749 					sizeof(struct iscsi_tcp_task) +
2750 					sizeof(struct cxgbi_task_data),
2751 					initial_cmdsn, ISCSI_MAX_TARGET);
2752 	if (!cls_session)
2753 		return NULL;
2754 
2755 	session = cls_session->dd_data;
2756 	if (iscsi_tcp_r2tpool_alloc(session))
2757 		goto remove_session;
2758 
2759 	log_debug(1 << CXGBI_DBG_ISCSI,
2760 		"ep 0x%p, cls sess 0x%p.\n", ep, cls_session);
2761 	return cls_session;
2762 
2763 remove_session:
2764 	iscsi_session_teardown(cls_session);
2765 	return NULL;
2766 }
2767 EXPORT_SYMBOL_GPL(cxgbi_create_session);
2768 
2769 void cxgbi_destroy_session(struct iscsi_cls_session *cls_session)
2770 {
2771 	log_debug(1 << CXGBI_DBG_ISCSI,
2772 		"cls sess 0x%p.\n", cls_session);
2773 
2774 	iscsi_tcp_r2tpool_free(cls_session->dd_data);
2775 	iscsi_session_teardown(cls_session);
2776 }
2777 EXPORT_SYMBOL_GPL(cxgbi_destroy_session);
2778 
2779 int cxgbi_set_host_param(struct Scsi_Host *shost, enum iscsi_host_param param,
2780 			char *buf, int buflen)
2781 {
2782 	struct cxgbi_hba *chba = iscsi_host_priv(shost);
2783 
2784 	if (!chba->ndev) {
2785 		shost_printk(KERN_ERR, shost, "Could not get host param. "
2786 				"netdev for host not set.\n");
2787 		return -ENODEV;
2788 	}
2789 
2790 	log_debug(1 << CXGBI_DBG_ISCSI,
2791 		"shost 0x%p, hba 0x%p,%s, param %d, buf(%d) %s.\n",
2792 		shost, chba, chba->ndev->name, param, buflen, buf);
2793 
2794 	switch (param) {
2795 	case ISCSI_HOST_PARAM_IPADDRESS:
2796 	{
2797 		__be32 addr = in_aton(buf);
2798 		log_debug(1 << CXGBI_DBG_ISCSI,
2799 			"hba %s, req. ipv4 %pI4.\n", chba->ndev->name, &addr);
2800 		cxgbi_set_iscsi_ipv4(chba, addr);
2801 		return 0;
2802 	}
2803 	case ISCSI_HOST_PARAM_HWADDRESS:
2804 	case ISCSI_HOST_PARAM_NETDEV_NAME:
2805 		return 0;
2806 	default:
2807 		return iscsi_host_set_param(shost, param, buf, buflen);
2808 	}
2809 }
2810 EXPORT_SYMBOL_GPL(cxgbi_set_host_param);
2811 
2812 int cxgbi_get_host_param(struct Scsi_Host *shost, enum iscsi_host_param param,
2813 			char *buf)
2814 {
2815 	struct cxgbi_hba *chba = iscsi_host_priv(shost);
2816 	int len = 0;
2817 
2818 	if (!chba->ndev) {
2819 		shost_printk(KERN_ERR, shost, "Could not get host param. "
2820 				"netdev for host not set.\n");
2821 		return -ENODEV;
2822 	}
2823 
2824 	log_debug(1 << CXGBI_DBG_ISCSI,
2825 		"shost 0x%p, hba 0x%p,%s, param %d.\n",
2826 		shost, chba, chba->ndev->name, param);
2827 
2828 	switch (param) {
2829 	case ISCSI_HOST_PARAM_HWADDRESS:
2830 		len = sysfs_format_mac(buf, chba->ndev->dev_addr, 6);
2831 		break;
2832 	case ISCSI_HOST_PARAM_NETDEV_NAME:
2833 		len = sprintf(buf, "%s\n", chba->ndev->name);
2834 		break;
2835 	case ISCSI_HOST_PARAM_IPADDRESS:
2836 	{
2837 		struct cxgbi_sock *csk = find_sock_on_port(chba->cdev,
2838 							   chba->port_id);
2839 		if (csk) {
2840 			len = sprintf(buf, "%pIS",
2841 				      (struct sockaddr *)&csk->saddr);
2842 		}
2843 		log_debug(1 << CXGBI_DBG_ISCSI,
2844 			  "hba %s, addr %s.\n", chba->ndev->name, buf);
2845 		break;
2846 	}
2847 	default:
2848 		return iscsi_host_get_param(shost, param, buf);
2849 	}
2850 
2851 	return len;
2852 }
2853 EXPORT_SYMBOL_GPL(cxgbi_get_host_param);
2854 
2855 struct iscsi_endpoint *cxgbi_ep_connect(struct Scsi_Host *shost,
2856 					struct sockaddr *dst_addr,
2857 					int non_blocking)
2858 {
2859 	struct iscsi_endpoint *ep;
2860 	struct cxgbi_endpoint *cep;
2861 	struct cxgbi_hba *hba = NULL;
2862 	struct cxgbi_sock *csk;
2863 	int ifindex = 0;
2864 	int err = -EINVAL;
2865 
2866 	log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_SOCK,
2867 		"shost 0x%p, non_blocking %d, dst_addr 0x%p.\n",
2868 		shost, non_blocking, dst_addr);
2869 
2870 	if (shost) {
2871 		hba = iscsi_host_priv(shost);
2872 		if (!hba) {
2873 			pr_info("shost 0x%p, priv NULL.\n", shost);
2874 			goto err_out;
2875 		}
2876 	}
2877 
2878 check_route:
2879 	if (dst_addr->sa_family == AF_INET) {
2880 		csk = cxgbi_check_route(dst_addr, ifindex);
2881 #if IS_ENABLED(CONFIG_IPV6)
2882 	} else if (dst_addr->sa_family == AF_INET6) {
2883 		csk = cxgbi_check_route6(dst_addr, ifindex);
2884 #endif
2885 	} else {
2886 		pr_info("address family 0x%x NOT supported.\n",
2887 			dst_addr->sa_family);
2888 		err = -EAFNOSUPPORT;
2889 		return (struct iscsi_endpoint *)ERR_PTR(err);
2890 	}
2891 
2892 	if (IS_ERR(csk))
2893 		return (struct iscsi_endpoint *)csk;
2894 	cxgbi_sock_get(csk);
2895 
2896 	if (!hba)
2897 		hba = csk->cdev->hbas[csk->port_id];
2898 	else if (hba != csk->cdev->hbas[csk->port_id]) {
2899 		if (ifindex != hba->ndev->ifindex) {
2900 			cxgbi_sock_put(csk);
2901 			cxgbi_sock_closed(csk);
2902 			ifindex = hba->ndev->ifindex;
2903 			goto check_route;
2904 		}
2905 
2906 		pr_info("Could not connect through requested host %u"
2907 			"hba 0x%p != 0x%p (%u).\n",
2908 			shost->host_no, hba,
2909 			csk->cdev->hbas[csk->port_id], csk->port_id);
2910 		err = -ENOSPC;
2911 		goto release_conn;
2912 	}
2913 
2914 	err = sock_get_port(csk);
2915 	if (err)
2916 		goto release_conn;
2917 
2918 	cxgbi_sock_set_state(csk, CTP_CONNECTING);
2919 	err = csk->cdev->csk_init_act_open(csk);
2920 	if (err)
2921 		goto release_conn;
2922 
2923 	if (cxgbi_sock_is_closing(csk)) {
2924 		err = -ENOSPC;
2925 		pr_info("csk 0x%p is closing.\n", csk);
2926 		goto release_conn;
2927 	}
2928 
2929 	ep = iscsi_create_endpoint(sizeof(*cep));
2930 	if (!ep) {
2931 		err = -ENOMEM;
2932 		pr_info("iscsi alloc ep, OOM.\n");
2933 		goto release_conn;
2934 	}
2935 
2936 	cep = ep->dd_data;
2937 	cep->csk = csk;
2938 	cep->chba = hba;
2939 
2940 	log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_SOCK,
2941 		"ep 0x%p, cep 0x%p, csk 0x%p, hba 0x%p,%s.\n",
2942 		ep, cep, csk, hba, hba->ndev->name);
2943 	return ep;
2944 
2945 release_conn:
2946 	cxgbi_sock_put(csk);
2947 	cxgbi_sock_closed(csk);
2948 err_out:
2949 	return ERR_PTR(err);
2950 }
2951 EXPORT_SYMBOL_GPL(cxgbi_ep_connect);
2952 
2953 int cxgbi_ep_poll(struct iscsi_endpoint *ep, int timeout_ms)
2954 {
2955 	struct cxgbi_endpoint *cep = ep->dd_data;
2956 	struct cxgbi_sock *csk = cep->csk;
2957 
2958 	if (!cxgbi_sock_is_established(csk))
2959 		return 0;
2960 	return 1;
2961 }
2962 EXPORT_SYMBOL_GPL(cxgbi_ep_poll);
2963 
2964 void cxgbi_ep_disconnect(struct iscsi_endpoint *ep)
2965 {
2966 	struct cxgbi_endpoint *cep = ep->dd_data;
2967 	struct cxgbi_conn *cconn = cep->cconn;
2968 	struct cxgbi_sock *csk = cep->csk;
2969 
2970 	log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_SOCK,
2971 		"ep 0x%p, cep 0x%p, cconn 0x%p, csk 0x%p,%u,0x%lx.\n",
2972 		ep, cep, cconn, csk, csk->state, csk->flags);
2973 
2974 	if (cconn && cconn->iconn) {
2975 		write_lock_bh(&csk->callback_lock);
2976 		cep->csk->user_data = NULL;
2977 		cconn->cep = NULL;
2978 		write_unlock_bh(&csk->callback_lock);
2979 	}
2980 	iscsi_destroy_endpoint(ep);
2981 
2982 	if (likely(csk->state >= CTP_ESTABLISHED))
2983 		need_active_close(csk);
2984 	else
2985 		cxgbi_sock_closed(csk);
2986 
2987 	cxgbi_sock_put(csk);
2988 }
2989 EXPORT_SYMBOL_GPL(cxgbi_ep_disconnect);
2990 
2991 int cxgbi_iscsi_init(struct iscsi_transport *itp,
2992 			struct scsi_transport_template **stt)
2993 {
2994 	*stt = iscsi_register_transport(itp);
2995 	if (*stt == NULL) {
2996 		pr_err("unable to register %s transport 0x%p.\n",
2997 			itp->name, itp);
2998 		return -ENODEV;
2999 	}
3000 	log_debug(1 << CXGBI_DBG_ISCSI,
3001 		"%s, registered iscsi transport 0x%p.\n",
3002 		itp->name, stt);
3003 	return 0;
3004 }
3005 EXPORT_SYMBOL_GPL(cxgbi_iscsi_init);
3006 
3007 void cxgbi_iscsi_cleanup(struct iscsi_transport *itp,
3008 			struct scsi_transport_template **stt)
3009 {
3010 	if (*stt) {
3011 		log_debug(1 << CXGBI_DBG_ISCSI,
3012 			"de-register transport 0x%p, %s, stt 0x%p.\n",
3013 			itp, itp->name, *stt);
3014 		*stt = NULL;
3015 		iscsi_unregister_transport(itp);
3016 	}
3017 }
3018 EXPORT_SYMBOL_GPL(cxgbi_iscsi_cleanup);
3019 
3020 umode_t cxgbi_attr_is_visible(int param_type, int param)
3021 {
3022 	switch (param_type) {
3023 	case ISCSI_HOST_PARAM:
3024 		switch (param) {
3025 		case ISCSI_HOST_PARAM_NETDEV_NAME:
3026 		case ISCSI_HOST_PARAM_HWADDRESS:
3027 		case ISCSI_HOST_PARAM_IPADDRESS:
3028 		case ISCSI_HOST_PARAM_INITIATOR_NAME:
3029 			return S_IRUGO;
3030 		default:
3031 			return 0;
3032 		}
3033 	case ISCSI_PARAM:
3034 		switch (param) {
3035 		case ISCSI_PARAM_MAX_RECV_DLENGTH:
3036 		case ISCSI_PARAM_MAX_XMIT_DLENGTH:
3037 		case ISCSI_PARAM_HDRDGST_EN:
3038 		case ISCSI_PARAM_DATADGST_EN:
3039 		case ISCSI_PARAM_CONN_ADDRESS:
3040 		case ISCSI_PARAM_CONN_PORT:
3041 		case ISCSI_PARAM_EXP_STATSN:
3042 		case ISCSI_PARAM_PERSISTENT_ADDRESS:
3043 		case ISCSI_PARAM_PERSISTENT_PORT:
3044 		case ISCSI_PARAM_PING_TMO:
3045 		case ISCSI_PARAM_RECV_TMO:
3046 		case ISCSI_PARAM_INITIAL_R2T_EN:
3047 		case ISCSI_PARAM_MAX_R2T:
3048 		case ISCSI_PARAM_IMM_DATA_EN:
3049 		case ISCSI_PARAM_FIRST_BURST:
3050 		case ISCSI_PARAM_MAX_BURST:
3051 		case ISCSI_PARAM_PDU_INORDER_EN:
3052 		case ISCSI_PARAM_DATASEQ_INORDER_EN:
3053 		case ISCSI_PARAM_ERL:
3054 		case ISCSI_PARAM_TARGET_NAME:
3055 		case ISCSI_PARAM_TPGT:
3056 		case ISCSI_PARAM_USERNAME:
3057 		case ISCSI_PARAM_PASSWORD:
3058 		case ISCSI_PARAM_USERNAME_IN:
3059 		case ISCSI_PARAM_PASSWORD_IN:
3060 		case ISCSI_PARAM_FAST_ABORT:
3061 		case ISCSI_PARAM_ABORT_TMO:
3062 		case ISCSI_PARAM_LU_RESET_TMO:
3063 		case ISCSI_PARAM_TGT_RESET_TMO:
3064 		case ISCSI_PARAM_IFACE_NAME:
3065 		case ISCSI_PARAM_INITIATOR_NAME:
3066 			return S_IRUGO;
3067 		default:
3068 			return 0;
3069 		}
3070 	}
3071 
3072 	return 0;
3073 }
3074 EXPORT_SYMBOL_GPL(cxgbi_attr_is_visible);
3075 
3076 static int __init libcxgbi_init_module(void)
3077 {
3078 	pr_info("%s", version);
3079 
3080 	BUILD_BUG_ON(sizeof_field(struct sk_buff, cb) <
3081 		     sizeof(struct cxgbi_skb_cb));
3082 	rsvd_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
3083 	if (!rsvd_page)
3084 		return -ENOMEM;
3085 
3086 	return 0;
3087 }
3088 
3089 static void __exit libcxgbi_exit_module(void)
3090 {
3091 	cxgbi_device_unregister_all(0xFF);
3092 	put_page(rsvd_page);
3093 	return;
3094 }
3095 
3096 module_init(libcxgbi_init_module);
3097 module_exit(libcxgbi_exit_module);
3098