xref: /openbmc/linux/drivers/scsi/cxgbi/libcxgbi.c (revision 3b64b188)
1 /*
2  * libcxgbi.c: Chelsio common library for T3/T4 iSCSI driver.
3  *
4  * Copyright (c) 2010 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 <linux/inetdevice.h>	/* ip_dev_find */
28 #include <linux/module.h>
29 #include <net/tcp.h>
30 
31 static unsigned int dbg_level;
32 
33 #include "libcxgbi.h"
34 
35 #define DRV_MODULE_NAME		"libcxgbi"
36 #define DRV_MODULE_DESC		"Chelsio iSCSI driver library"
37 #define DRV_MODULE_VERSION	"0.9.0"
38 #define DRV_MODULE_RELDATE	"Jun. 2010"
39 
40 MODULE_AUTHOR("Chelsio Communications, Inc.");
41 MODULE_DESCRIPTION(DRV_MODULE_DESC);
42 MODULE_VERSION(DRV_MODULE_VERSION);
43 MODULE_LICENSE("GPL");
44 
45 module_param(dbg_level, uint, 0644);
46 MODULE_PARM_DESC(dbg_level, "libiscsi debug level (default=0)");
47 
48 
49 /*
50  * cxgbi device management
51  * maintains a list of the cxgbi devices
52  */
53 static LIST_HEAD(cdev_list);
54 static DEFINE_MUTEX(cdev_mutex);
55 
56 int cxgbi_device_portmap_create(struct cxgbi_device *cdev, unsigned int base,
57 				unsigned int max_conn)
58 {
59 	struct cxgbi_ports_map *pmap = &cdev->pmap;
60 
61 	pmap->port_csk = cxgbi_alloc_big_mem(max_conn *
62 					     sizeof(struct cxgbi_sock *),
63 					     GFP_KERNEL);
64 	if (!pmap->port_csk) {
65 		pr_warn("cdev 0x%p, portmap OOM %u.\n", cdev, max_conn);
66 		return -ENOMEM;
67 	}
68 
69 	pmap->max_connect = max_conn;
70 	pmap->sport_base = base;
71 	spin_lock_init(&pmap->lock);
72 	return 0;
73 }
74 EXPORT_SYMBOL_GPL(cxgbi_device_portmap_create);
75 
76 void cxgbi_device_portmap_cleanup(struct cxgbi_device *cdev)
77 {
78 	struct cxgbi_ports_map *pmap = &cdev->pmap;
79 	struct cxgbi_sock *csk;
80 	int i;
81 
82 	for (i = 0; i < pmap->max_connect; i++) {
83 		if (pmap->port_csk[i]) {
84 			csk = pmap->port_csk[i];
85 			pmap->port_csk[i] = NULL;
86 			log_debug(1 << CXGBI_DBG_SOCK,
87 				"csk 0x%p, cdev 0x%p, offload down.\n",
88 				csk, cdev);
89 			spin_lock_bh(&csk->lock);
90 			cxgbi_sock_set_flag(csk, CTPF_OFFLOAD_DOWN);
91 			cxgbi_sock_closed(csk);
92 			spin_unlock_bh(&csk->lock);
93 			cxgbi_sock_put(csk);
94 		}
95 	}
96 }
97 EXPORT_SYMBOL_GPL(cxgbi_device_portmap_cleanup);
98 
99 static inline void cxgbi_device_destroy(struct cxgbi_device *cdev)
100 {
101 	log_debug(1 << CXGBI_DBG_DEV,
102 		"cdev 0x%p, p# %u.\n", cdev, cdev->nports);
103 	cxgbi_hbas_remove(cdev);
104 	cxgbi_device_portmap_cleanup(cdev);
105 	if (cdev->dev_ddp_cleanup)
106 		cdev->dev_ddp_cleanup(cdev);
107 	else
108 		cxgbi_ddp_cleanup(cdev);
109 	if (cdev->ddp)
110 		cxgbi_ddp_cleanup(cdev);
111 	if (cdev->pmap.max_connect)
112 		cxgbi_free_big_mem(cdev->pmap.port_csk);
113 	kfree(cdev);
114 }
115 
116 struct cxgbi_device *cxgbi_device_register(unsigned int extra,
117 					   unsigned int nports)
118 {
119 	struct cxgbi_device *cdev;
120 
121 	cdev = kzalloc(sizeof(*cdev) + extra + nports *
122 			(sizeof(struct cxgbi_hba *) +
123 			 sizeof(struct net_device *)),
124 			GFP_KERNEL);
125 	if (!cdev) {
126 		pr_warn("nport %d, OOM.\n", nports);
127 		return NULL;
128 	}
129 	cdev->ports = (struct net_device **)(cdev + 1);
130 	cdev->hbas = (struct cxgbi_hba **)(((char*)cdev->ports) + nports *
131 						sizeof(struct net_device *));
132 	if (extra)
133 		cdev->dd_data = ((char *)cdev->hbas) +
134 				nports * sizeof(struct cxgbi_hba *);
135 	spin_lock_init(&cdev->pmap.lock);
136 
137 	mutex_lock(&cdev_mutex);
138 	list_add_tail(&cdev->list_head, &cdev_list);
139 	mutex_unlock(&cdev_mutex);
140 
141 	log_debug(1 << CXGBI_DBG_DEV,
142 		"cdev 0x%p, p# %u.\n", cdev, nports);
143 	return cdev;
144 }
145 EXPORT_SYMBOL_GPL(cxgbi_device_register);
146 
147 void cxgbi_device_unregister(struct cxgbi_device *cdev)
148 {
149 	log_debug(1 << CXGBI_DBG_DEV,
150 		"cdev 0x%p, p# %u,%s.\n",
151 		cdev, cdev->nports, cdev->nports ? cdev->ports[0]->name : "");
152 	mutex_lock(&cdev_mutex);
153 	list_del(&cdev->list_head);
154 	mutex_unlock(&cdev_mutex);
155 	cxgbi_device_destroy(cdev);
156 }
157 EXPORT_SYMBOL_GPL(cxgbi_device_unregister);
158 
159 void cxgbi_device_unregister_all(unsigned int flag)
160 {
161 	struct cxgbi_device *cdev, *tmp;
162 
163 	mutex_lock(&cdev_mutex);
164 	list_for_each_entry_safe(cdev, tmp, &cdev_list, list_head) {
165 		if ((cdev->flags & flag) == flag) {
166 			log_debug(1 << CXGBI_DBG_DEV,
167 				"cdev 0x%p, p# %u,%s.\n",
168 				cdev, cdev->nports, cdev->nports ?
169 				 cdev->ports[0]->name : "");
170 			list_del(&cdev->list_head);
171 			cxgbi_device_destroy(cdev);
172 		}
173 	}
174 	mutex_unlock(&cdev_mutex);
175 }
176 EXPORT_SYMBOL_GPL(cxgbi_device_unregister_all);
177 
178 struct cxgbi_device *cxgbi_device_find_by_lldev(void *lldev)
179 {
180 	struct cxgbi_device *cdev, *tmp;
181 
182 	mutex_lock(&cdev_mutex);
183 	list_for_each_entry_safe(cdev, tmp, &cdev_list, list_head) {
184 		if (cdev->lldev == lldev) {
185 			mutex_unlock(&cdev_mutex);
186 			return cdev;
187 		}
188 	}
189 	mutex_unlock(&cdev_mutex);
190 	log_debug(1 << CXGBI_DBG_DEV,
191 		"lldev 0x%p, NO match found.\n", lldev);
192 	return NULL;
193 }
194 EXPORT_SYMBOL_GPL(cxgbi_device_find_by_lldev);
195 
196 static struct cxgbi_device *cxgbi_device_find_by_netdev(struct net_device *ndev,
197 							int *port)
198 {
199 	struct net_device *vdev = NULL;
200 	struct cxgbi_device *cdev, *tmp;
201 	int i;
202 
203 	if (ndev->priv_flags & IFF_802_1Q_VLAN) {
204 		vdev = ndev;
205 		ndev = vlan_dev_real_dev(ndev);
206 		log_debug(1 << CXGBI_DBG_DEV,
207 			"vlan dev %s -> %s.\n", vdev->name, ndev->name);
208 	}
209 
210 	mutex_lock(&cdev_mutex);
211 	list_for_each_entry_safe(cdev, tmp, &cdev_list, list_head) {
212 		for (i = 0; i < cdev->nports; i++) {
213 			if (ndev == cdev->ports[i]) {
214 				cdev->hbas[i]->vdev = vdev;
215 				mutex_unlock(&cdev_mutex);
216 				if (port)
217 					*port = i;
218 				return cdev;
219 			}
220 		}
221 	}
222 	mutex_unlock(&cdev_mutex);
223 	log_debug(1 << CXGBI_DBG_DEV,
224 		"ndev 0x%p, %s, NO match found.\n", ndev, ndev->name);
225 	return NULL;
226 }
227 
228 void cxgbi_hbas_remove(struct cxgbi_device *cdev)
229 {
230 	int i;
231 	struct cxgbi_hba *chba;
232 
233 	log_debug(1 << CXGBI_DBG_DEV,
234 		"cdev 0x%p, p#%u.\n", cdev, cdev->nports);
235 
236 	for (i = 0; i < cdev->nports; i++) {
237 		chba = cdev->hbas[i];
238 		if (chba) {
239 			cdev->hbas[i] = NULL;
240 			iscsi_host_remove(chba->shost);
241 			pci_dev_put(cdev->pdev);
242 			iscsi_host_free(chba->shost);
243 		}
244 	}
245 }
246 EXPORT_SYMBOL_GPL(cxgbi_hbas_remove);
247 
248 int cxgbi_hbas_add(struct cxgbi_device *cdev, unsigned int max_lun,
249 		unsigned int max_id, struct scsi_host_template *sht,
250 		struct scsi_transport_template *stt)
251 {
252 	struct cxgbi_hba *chba;
253 	struct Scsi_Host *shost;
254 	int i, err;
255 
256 	log_debug(1 << CXGBI_DBG_DEV, "cdev 0x%p, p#%u.\n", cdev, cdev->nports);
257 
258 	for (i = 0; i < cdev->nports; i++) {
259 		shost = iscsi_host_alloc(sht, sizeof(*chba), 1);
260 		if (!shost) {
261 			pr_info("0x%p, p%d, %s, host alloc failed.\n",
262 				cdev, i, cdev->ports[i]->name);
263 			err = -ENOMEM;
264 			goto err_out;
265 		}
266 
267 		shost->transportt = stt;
268 		shost->max_lun = max_lun;
269 		shost->max_id = max_id;
270 		shost->max_channel = 0;
271 		shost->max_cmd_len = 16;
272 
273 		chba = iscsi_host_priv(shost);
274 		chba->cdev = cdev;
275 		chba->ndev = cdev->ports[i];
276 		chba->shost = shost;
277 
278 		log_debug(1 << CXGBI_DBG_DEV,
279 			"cdev 0x%p, p#%d %s: chba 0x%p.\n",
280 			cdev, i, cdev->ports[i]->name, chba);
281 
282 		pci_dev_get(cdev->pdev);
283 		err = iscsi_host_add(shost, &cdev->pdev->dev);
284 		if (err) {
285 			pr_info("cdev 0x%p, p#%d %s, host add failed.\n",
286 				cdev, i, cdev->ports[i]->name);
287 			pci_dev_put(cdev->pdev);
288 			scsi_host_put(shost);
289 			goto  err_out;
290 		}
291 
292 		cdev->hbas[i] = chba;
293 	}
294 
295 	return 0;
296 
297 err_out:
298 	cxgbi_hbas_remove(cdev);
299 	return err;
300 }
301 EXPORT_SYMBOL_GPL(cxgbi_hbas_add);
302 
303 /*
304  * iSCSI offload
305  *
306  * - source port management
307  *   To find a free source port in the port allocation map we use a very simple
308  *   rotor scheme to look for the next free port.
309  *
310  *   If a source port has been specified make sure that it doesn't collide with
311  *   our normal source port allocation map.  If it's outside the range of our
312  *   allocation/deallocation scheme just let them use it.
313  *
314  *   If the source port is outside our allocation range, the caller is
315  *   responsible for keeping track of their port usage.
316  */
317 static int sock_get_port(struct cxgbi_sock *csk)
318 {
319 	struct cxgbi_device *cdev = csk->cdev;
320 	struct cxgbi_ports_map *pmap = &cdev->pmap;
321 	unsigned int start;
322 	int idx;
323 
324 	if (!pmap->max_connect) {
325 		pr_err("cdev 0x%p, p#%u %s, NO port map.\n",
326 			   cdev, csk->port_id, cdev->ports[csk->port_id]->name);
327 		return -EADDRNOTAVAIL;
328 	}
329 
330 	if (csk->saddr.sin_port) {
331 		pr_err("source port NON-ZERO %u.\n",
332 			ntohs(csk->saddr.sin_port));
333 		return -EADDRINUSE;
334 	}
335 
336 	spin_lock_bh(&pmap->lock);
337 	if (pmap->used >= pmap->max_connect) {
338 		spin_unlock_bh(&pmap->lock);
339 		pr_info("cdev 0x%p, p#%u %s, ALL ports used.\n",
340 			cdev, csk->port_id, cdev->ports[csk->port_id]->name);
341 		return -EADDRNOTAVAIL;
342 	}
343 
344 	start = idx = pmap->next;
345 	do {
346 		if (++idx >= pmap->max_connect)
347 			idx = 0;
348 		if (!pmap->port_csk[idx]) {
349 			pmap->used++;
350 			csk->saddr.sin_port =
351 				htons(pmap->sport_base + idx);
352 			pmap->next = idx;
353 			pmap->port_csk[idx] = csk;
354 			spin_unlock_bh(&pmap->lock);
355 			cxgbi_sock_get(csk);
356 			log_debug(1 << CXGBI_DBG_SOCK,
357 				"cdev 0x%p, p#%u %s, p %u, %u.\n",
358 				cdev, csk->port_id,
359 				cdev->ports[csk->port_id]->name,
360 				pmap->sport_base + idx, pmap->next);
361 			return 0;
362 		}
363 	} while (idx != start);
364 	spin_unlock_bh(&pmap->lock);
365 
366 	/* should not happen */
367 	pr_warn("cdev 0x%p, p#%u %s, next %u?\n",
368 		cdev, csk->port_id, cdev->ports[csk->port_id]->name,
369 		pmap->next);
370 	return -EADDRNOTAVAIL;
371 }
372 
373 static void sock_put_port(struct cxgbi_sock *csk)
374 {
375 	struct cxgbi_device *cdev = csk->cdev;
376 	struct cxgbi_ports_map *pmap = &cdev->pmap;
377 
378 	if (csk->saddr.sin_port) {
379 		int idx = ntohs(csk->saddr.sin_port) - pmap->sport_base;
380 
381 		csk->saddr.sin_port = 0;
382 		if (idx < 0 || idx >= pmap->max_connect) {
383 			pr_err("cdev 0x%p, p#%u %s, port %u OOR.\n",
384 				cdev, csk->port_id,
385 				cdev->ports[csk->port_id]->name,
386 				ntohs(csk->saddr.sin_port));
387 			return;
388 		}
389 
390 		spin_lock_bh(&pmap->lock);
391 		pmap->port_csk[idx] = NULL;
392 		pmap->used--;
393 		spin_unlock_bh(&pmap->lock);
394 
395 		log_debug(1 << CXGBI_DBG_SOCK,
396 			"cdev 0x%p, p#%u %s, release %u.\n",
397 			cdev, csk->port_id, cdev->ports[csk->port_id]->name,
398 			pmap->sport_base + idx);
399 
400 		cxgbi_sock_put(csk);
401 	}
402 }
403 
404 /*
405  * iscsi tcp connection
406  */
407 void cxgbi_sock_free_cpl_skbs(struct cxgbi_sock *csk)
408 {
409 	if (csk->cpl_close) {
410 		kfree_skb(csk->cpl_close);
411 		csk->cpl_close = NULL;
412 	}
413 	if (csk->cpl_abort_req) {
414 		kfree_skb(csk->cpl_abort_req);
415 		csk->cpl_abort_req = NULL;
416 	}
417 	if (csk->cpl_abort_rpl) {
418 		kfree_skb(csk->cpl_abort_rpl);
419 		csk->cpl_abort_rpl = NULL;
420 	}
421 }
422 EXPORT_SYMBOL_GPL(cxgbi_sock_free_cpl_skbs);
423 
424 static struct cxgbi_sock *cxgbi_sock_create(struct cxgbi_device *cdev)
425 {
426 	struct cxgbi_sock *csk = kzalloc(sizeof(*csk), GFP_NOIO);
427 
428 	if (!csk) {
429 		pr_info("alloc csk %zu failed.\n", sizeof(*csk));
430 		return NULL;
431 	}
432 
433 	if (cdev->csk_alloc_cpls(csk) < 0) {
434 		pr_info("csk 0x%p, alloc cpls failed.\n", csk);
435 		kfree(csk);
436 		return NULL;
437 	}
438 
439 	spin_lock_init(&csk->lock);
440 	kref_init(&csk->refcnt);
441 	skb_queue_head_init(&csk->receive_queue);
442 	skb_queue_head_init(&csk->write_queue);
443 	setup_timer(&csk->retry_timer, NULL, (unsigned long)csk);
444 	rwlock_init(&csk->callback_lock);
445 	csk->cdev = cdev;
446 	csk->flags = 0;
447 	cxgbi_sock_set_state(csk, CTP_CLOSED);
448 
449 	log_debug(1 << CXGBI_DBG_SOCK, "cdev 0x%p, new csk 0x%p.\n", cdev, csk);
450 
451 	return csk;
452 }
453 
454 static struct rtable *find_route_ipv4(struct flowi4 *fl4,
455 				      __be32 saddr, __be32 daddr,
456 				      __be16 sport, __be16 dport, u8 tos)
457 {
458 	struct rtable *rt;
459 
460 	rt = ip_route_output_ports(&init_net, fl4, NULL, daddr, saddr,
461 				   dport, sport, IPPROTO_TCP, tos, 0);
462 	if (IS_ERR(rt))
463 		return NULL;
464 
465 	return rt;
466 }
467 
468 static struct cxgbi_sock *cxgbi_check_route(struct sockaddr *dst_addr)
469 {
470 	struct sockaddr_in *daddr = (struct sockaddr_in *)dst_addr;
471 	struct dst_entry *dst;
472 	struct net_device *ndev;
473 	struct cxgbi_device *cdev;
474 	struct rtable *rt = NULL;
475 	struct neighbour *n;
476 	struct flowi4 fl4;
477 	struct cxgbi_sock *csk = NULL;
478 	unsigned int mtu = 0;
479 	int port = 0xFFFF;
480 	int err = 0;
481 
482 	if (daddr->sin_family != AF_INET) {
483 		pr_info("address family 0x%x NOT supported.\n",
484 			daddr->sin_family);
485 		err = -EAFNOSUPPORT;
486 		goto err_out;
487 	}
488 
489 	rt = find_route_ipv4(&fl4, 0, daddr->sin_addr.s_addr, 0, daddr->sin_port, 0);
490 	if (!rt) {
491 		pr_info("no route to ipv4 0x%x, port %u.\n",
492 			daddr->sin_addr.s_addr, daddr->sin_port);
493 		err = -ENETUNREACH;
494 		goto err_out;
495 	}
496 	dst = &rt->dst;
497 	n = dst_neigh_lookup(dst, &daddr->sin_addr.s_addr);
498 	if (!n) {
499 		err = -ENODEV;
500 		goto rel_rt;
501 	}
502 	ndev = n->dev;
503 
504 	if (rt->rt_flags & (RTCF_MULTICAST | RTCF_BROADCAST)) {
505 		pr_info("multi-cast route %pI4, port %u, dev %s.\n",
506 			&daddr->sin_addr.s_addr, ntohs(daddr->sin_port),
507 			ndev->name);
508 		err = -ENETUNREACH;
509 		goto rel_neigh;
510 	}
511 
512 	if (ndev->flags & IFF_LOOPBACK) {
513 		ndev = ip_dev_find(&init_net, daddr->sin_addr.s_addr);
514 		mtu = ndev->mtu;
515 		pr_info("rt dev %s, loopback -> %s, mtu %u.\n",
516 			n->dev->name, ndev->name, mtu);
517 	}
518 
519 	cdev = cxgbi_device_find_by_netdev(ndev, &port);
520 	if (!cdev) {
521 		pr_info("dst %pI4, %s, NOT cxgbi device.\n",
522 			&daddr->sin_addr.s_addr, ndev->name);
523 		err = -ENETUNREACH;
524 		goto rel_neigh;
525 	}
526 	log_debug(1 << CXGBI_DBG_SOCK,
527 		"route to %pI4 :%u, ndev p#%d,%s, cdev 0x%p.\n",
528 		&daddr->sin_addr.s_addr, ntohs(daddr->sin_port),
529 			   port, ndev->name, cdev);
530 
531 	csk = cxgbi_sock_create(cdev);
532 	if (!csk) {
533 		err = -ENOMEM;
534 		goto rel_neigh;
535 	}
536 	csk->cdev = cdev;
537 	csk->port_id = port;
538 	csk->mtu = mtu;
539 	csk->dst = dst;
540 	csk->daddr.sin_addr.s_addr = daddr->sin_addr.s_addr;
541 	csk->daddr.sin_port = daddr->sin_port;
542 	csk->daddr.sin_family = daddr->sin_family;
543 	csk->saddr.sin_addr.s_addr = fl4.saddr;
544 	neigh_release(n);
545 
546 	return csk;
547 
548 rel_neigh:
549 	neigh_release(n);
550 
551 rel_rt:
552 	ip_rt_put(rt);
553 	if (csk)
554 		cxgbi_sock_closed(csk);
555 err_out:
556 	return ERR_PTR(err);
557 }
558 
559 void cxgbi_sock_established(struct cxgbi_sock *csk, unsigned int snd_isn,
560 			unsigned int opt)
561 {
562 	csk->write_seq = csk->snd_nxt = csk->snd_una = snd_isn;
563 	dst_confirm(csk->dst);
564 	smp_mb();
565 	cxgbi_sock_set_state(csk, CTP_ESTABLISHED);
566 }
567 EXPORT_SYMBOL_GPL(cxgbi_sock_established);
568 
569 static void cxgbi_inform_iscsi_conn_closing(struct cxgbi_sock *csk)
570 {
571 	log_debug(1 << CXGBI_DBG_SOCK,
572 		"csk 0x%p, state %u, flags 0x%lx, conn 0x%p.\n",
573 		csk, csk->state, csk->flags, csk->user_data);
574 
575 	if (csk->state != CTP_ESTABLISHED) {
576 		read_lock_bh(&csk->callback_lock);
577 		if (csk->user_data)
578 			iscsi_conn_failure(csk->user_data,
579 					ISCSI_ERR_CONN_FAILED);
580 		read_unlock_bh(&csk->callback_lock);
581 	}
582 }
583 
584 void cxgbi_sock_closed(struct cxgbi_sock *csk)
585 {
586 	log_debug(1 << CXGBI_DBG_SOCK, "csk 0x%p,%u,0x%lx,%u.\n",
587 		csk, (csk)->state, (csk)->flags, (csk)->tid);
588 	cxgbi_sock_set_flag(csk, CTPF_ACTIVE_CLOSE_NEEDED);
589 	if (csk->state == CTP_ACTIVE_OPEN || csk->state == CTP_CLOSED)
590 		return;
591 	if (csk->saddr.sin_port)
592 		sock_put_port(csk);
593 	if (csk->dst)
594 		dst_release(csk->dst);
595 	csk->cdev->csk_release_offload_resources(csk);
596 	cxgbi_sock_set_state(csk, CTP_CLOSED);
597 	cxgbi_inform_iscsi_conn_closing(csk);
598 	cxgbi_sock_put(csk);
599 }
600 EXPORT_SYMBOL_GPL(cxgbi_sock_closed);
601 
602 static void need_active_close(struct cxgbi_sock *csk)
603 {
604 	int data_lost;
605 	int close_req = 0;
606 
607 	log_debug(1 << CXGBI_DBG_SOCK, "csk 0x%p,%u,0x%lx,%u.\n",
608 		csk, (csk)->state, (csk)->flags, (csk)->tid);
609 	spin_lock_bh(&csk->lock);
610 	dst_confirm(csk->dst);
611 	data_lost = skb_queue_len(&csk->receive_queue);
612 	__skb_queue_purge(&csk->receive_queue);
613 
614 	if (csk->state == CTP_ACTIVE_OPEN)
615 		cxgbi_sock_set_flag(csk, CTPF_ACTIVE_CLOSE_NEEDED);
616 	else if (csk->state == CTP_ESTABLISHED) {
617 		close_req = 1;
618 		cxgbi_sock_set_state(csk, CTP_ACTIVE_CLOSE);
619 	} else if (csk->state == CTP_PASSIVE_CLOSE) {
620 		close_req = 1;
621 		cxgbi_sock_set_state(csk, CTP_CLOSE_WAIT_2);
622 	}
623 
624 	if (close_req) {
625 		if (data_lost)
626 			csk->cdev->csk_send_abort_req(csk);
627 		else
628 			csk->cdev->csk_send_close_req(csk);
629 	}
630 
631 	spin_unlock_bh(&csk->lock);
632 }
633 
634 void cxgbi_sock_fail_act_open(struct cxgbi_sock *csk, int errno)
635 {
636 	pr_info("csk 0x%p,%u,%lx, %pI4:%u-%pI4:%u, err %d.\n",
637 			csk, csk->state, csk->flags,
638 			&csk->saddr.sin_addr.s_addr, csk->saddr.sin_port,
639 			&csk->daddr.sin_addr.s_addr, csk->daddr.sin_port,
640 			errno);
641 
642 	cxgbi_sock_set_state(csk, CTP_CONNECTING);
643 	csk->err = errno;
644 	cxgbi_sock_closed(csk);
645 }
646 EXPORT_SYMBOL_GPL(cxgbi_sock_fail_act_open);
647 
648 void cxgbi_sock_act_open_req_arp_failure(void *handle, struct sk_buff *skb)
649 {
650 	struct cxgbi_sock *csk = (struct cxgbi_sock *)skb->sk;
651 
652 	log_debug(1 << CXGBI_DBG_SOCK, "csk 0x%p,%u,0x%lx,%u.\n",
653 		csk, (csk)->state, (csk)->flags, (csk)->tid);
654 	cxgbi_sock_get(csk);
655 	spin_lock_bh(&csk->lock);
656 	if (csk->state == CTP_ACTIVE_OPEN)
657 		cxgbi_sock_fail_act_open(csk, -EHOSTUNREACH);
658 	spin_unlock_bh(&csk->lock);
659 	cxgbi_sock_put(csk);
660 	__kfree_skb(skb);
661 }
662 EXPORT_SYMBOL_GPL(cxgbi_sock_act_open_req_arp_failure);
663 
664 void cxgbi_sock_rcv_abort_rpl(struct cxgbi_sock *csk)
665 {
666 	cxgbi_sock_get(csk);
667 	spin_lock_bh(&csk->lock);
668 	if (cxgbi_sock_flag(csk, CTPF_ABORT_RPL_PENDING)) {
669 		if (!cxgbi_sock_flag(csk, CTPF_ABORT_RPL_RCVD))
670 			cxgbi_sock_set_flag(csk, CTPF_ABORT_RPL_RCVD);
671 		else {
672 			cxgbi_sock_clear_flag(csk, CTPF_ABORT_RPL_RCVD);
673 			cxgbi_sock_clear_flag(csk, CTPF_ABORT_RPL_PENDING);
674 			if (cxgbi_sock_flag(csk, CTPF_ABORT_REQ_RCVD))
675 				pr_err("csk 0x%p,%u,0x%lx,%u,ABT_RPL_RSS.\n",
676 					csk, csk->state, csk->flags, csk->tid);
677 			cxgbi_sock_closed(csk);
678 		}
679 	}
680 	spin_unlock_bh(&csk->lock);
681 	cxgbi_sock_put(csk);
682 }
683 EXPORT_SYMBOL_GPL(cxgbi_sock_rcv_abort_rpl);
684 
685 void cxgbi_sock_rcv_peer_close(struct cxgbi_sock *csk)
686 {
687 	log_debug(1 << CXGBI_DBG_SOCK, "csk 0x%p,%u,0x%lx,%u.\n",
688 		csk, (csk)->state, (csk)->flags, (csk)->tid);
689 	cxgbi_sock_get(csk);
690 	spin_lock_bh(&csk->lock);
691 
692 	if (cxgbi_sock_flag(csk, CTPF_ABORT_RPL_PENDING))
693 		goto done;
694 
695 	switch (csk->state) {
696 	case CTP_ESTABLISHED:
697 		cxgbi_sock_set_state(csk, CTP_PASSIVE_CLOSE);
698 		break;
699 	case CTP_ACTIVE_CLOSE:
700 		cxgbi_sock_set_state(csk, CTP_CLOSE_WAIT_2);
701 		break;
702 	case CTP_CLOSE_WAIT_1:
703 		cxgbi_sock_closed(csk);
704 		break;
705 	case CTP_ABORTING:
706 		break;
707 	default:
708 		pr_err("csk 0x%p,%u,0x%lx,%u, bad state.\n",
709 			csk, csk->state, csk->flags, csk->tid);
710 	}
711 	cxgbi_inform_iscsi_conn_closing(csk);
712 done:
713 	spin_unlock_bh(&csk->lock);
714 	cxgbi_sock_put(csk);
715 }
716 EXPORT_SYMBOL_GPL(cxgbi_sock_rcv_peer_close);
717 
718 void cxgbi_sock_rcv_close_conn_rpl(struct cxgbi_sock *csk, u32 snd_nxt)
719 {
720 	log_debug(1 << CXGBI_DBG_SOCK, "csk 0x%p,%u,0x%lx,%u.\n",
721 		csk, (csk)->state, (csk)->flags, (csk)->tid);
722 	cxgbi_sock_get(csk);
723 	spin_lock_bh(&csk->lock);
724 
725 	csk->snd_una = snd_nxt - 1;
726 	if (cxgbi_sock_flag(csk, CTPF_ABORT_RPL_PENDING))
727 		goto done;
728 
729 	switch (csk->state) {
730 	case CTP_ACTIVE_CLOSE:
731 		cxgbi_sock_set_state(csk, CTP_CLOSE_WAIT_1);
732 		break;
733 	case CTP_CLOSE_WAIT_1:
734 	case CTP_CLOSE_WAIT_2:
735 		cxgbi_sock_closed(csk);
736 		break;
737 	case CTP_ABORTING:
738 		break;
739 	default:
740 		pr_err("csk 0x%p,%u,0x%lx,%u, bad state.\n",
741 			csk, csk->state, csk->flags, csk->tid);
742 	}
743 done:
744 	spin_unlock_bh(&csk->lock);
745 	cxgbi_sock_put(csk);
746 }
747 EXPORT_SYMBOL_GPL(cxgbi_sock_rcv_close_conn_rpl);
748 
749 void cxgbi_sock_rcv_wr_ack(struct cxgbi_sock *csk, unsigned int credits,
750 			   unsigned int snd_una, int seq_chk)
751 {
752 	log_debug(1 << CXGBI_DBG_TOE | 1 << CXGBI_DBG_SOCK,
753 			"csk 0x%p,%u,0x%lx,%u, cr %u,%u+%u, snd_una %u,%d.\n",
754 			csk, csk->state, csk->flags, csk->tid, credits,
755 			csk->wr_cred, csk->wr_una_cred, snd_una, seq_chk);
756 
757 	spin_lock_bh(&csk->lock);
758 
759 	csk->wr_cred += credits;
760 	if (csk->wr_una_cred > csk->wr_max_cred - csk->wr_cred)
761 		csk->wr_una_cred = csk->wr_max_cred - csk->wr_cred;
762 
763 	while (credits) {
764 		struct sk_buff *p = cxgbi_sock_peek_wr(csk);
765 
766 		if (unlikely(!p)) {
767 			pr_err("csk 0x%p,%u,0x%lx,%u, cr %u,%u+%u, empty.\n",
768 				csk, csk->state, csk->flags, csk->tid, credits,
769 				csk->wr_cred, csk->wr_una_cred);
770 			break;
771 		}
772 
773 		if (unlikely(credits < p->csum)) {
774 			pr_warn("csk 0x%p,%u,0x%lx,%u, cr %u,%u+%u, < %u.\n",
775 				csk, csk->state, csk->flags, csk->tid,
776 				credits, csk->wr_cred, csk->wr_una_cred,
777 				p->csum);
778 			p->csum -= credits;
779 			break;
780 		} else {
781 			cxgbi_sock_dequeue_wr(csk);
782 			credits -= p->csum;
783 			kfree_skb(p);
784 		}
785 	}
786 
787 	cxgbi_sock_check_wr_invariants(csk);
788 
789 	if (seq_chk) {
790 		if (unlikely(before(snd_una, csk->snd_una))) {
791 			pr_warn("csk 0x%p,%u,0x%lx,%u, snd_una %u/%u.",
792 				csk, csk->state, csk->flags, csk->tid, snd_una,
793 				csk->snd_una);
794 			goto done;
795 		}
796 
797 		if (csk->snd_una != snd_una) {
798 			csk->snd_una = snd_una;
799 			dst_confirm(csk->dst);
800 		}
801 	}
802 
803 	if (skb_queue_len(&csk->write_queue)) {
804 		if (csk->cdev->csk_push_tx_frames(csk, 0))
805 			cxgbi_conn_tx_open(csk);
806 	} else
807 		cxgbi_conn_tx_open(csk);
808 done:
809 	spin_unlock_bh(&csk->lock);
810 }
811 EXPORT_SYMBOL_GPL(cxgbi_sock_rcv_wr_ack);
812 
813 static unsigned int cxgbi_sock_find_best_mtu(struct cxgbi_sock *csk,
814 					     unsigned short mtu)
815 {
816 	int i = 0;
817 
818 	while (i < csk->cdev->nmtus - 1 && csk->cdev->mtus[i + 1] <= mtu)
819 		++i;
820 
821 	return i;
822 }
823 
824 unsigned int cxgbi_sock_select_mss(struct cxgbi_sock *csk, unsigned int pmtu)
825 {
826 	unsigned int idx;
827 	struct dst_entry *dst = csk->dst;
828 
829 	csk->advmss = dst_metric_advmss(dst);
830 
831 	if (csk->advmss > pmtu - 40)
832 		csk->advmss = pmtu - 40;
833 	if (csk->advmss < csk->cdev->mtus[0] - 40)
834 		csk->advmss = csk->cdev->mtus[0] - 40;
835 	idx = cxgbi_sock_find_best_mtu(csk, csk->advmss + 40);
836 
837 	return idx;
838 }
839 EXPORT_SYMBOL_GPL(cxgbi_sock_select_mss);
840 
841 void cxgbi_sock_skb_entail(struct cxgbi_sock *csk, struct sk_buff *skb)
842 {
843 	cxgbi_skcb_tcp_seq(skb) = csk->write_seq;
844 	__skb_queue_tail(&csk->write_queue, skb);
845 }
846 EXPORT_SYMBOL_GPL(cxgbi_sock_skb_entail);
847 
848 void cxgbi_sock_purge_wr_queue(struct cxgbi_sock *csk)
849 {
850 	struct sk_buff *skb;
851 
852 	while ((skb = cxgbi_sock_dequeue_wr(csk)) != NULL)
853 		kfree_skb(skb);
854 }
855 EXPORT_SYMBOL_GPL(cxgbi_sock_purge_wr_queue);
856 
857 void cxgbi_sock_check_wr_invariants(const struct cxgbi_sock *csk)
858 {
859 	int pending = cxgbi_sock_count_pending_wrs(csk);
860 
861 	if (unlikely(csk->wr_cred + pending != csk->wr_max_cred))
862 		pr_err("csk 0x%p, tid %u, credit %u + %u != %u.\n",
863 			csk, csk->tid, csk->wr_cred, pending, csk->wr_max_cred);
864 }
865 EXPORT_SYMBOL_GPL(cxgbi_sock_check_wr_invariants);
866 
867 static int cxgbi_sock_send_pdus(struct cxgbi_sock *csk, struct sk_buff *skb)
868 {
869 	struct cxgbi_device *cdev = csk->cdev;
870 	struct sk_buff *next;
871 	int err, copied = 0;
872 
873 	spin_lock_bh(&csk->lock);
874 
875 	if (csk->state != CTP_ESTABLISHED) {
876 		log_debug(1 << CXGBI_DBG_PDU_TX,
877 			"csk 0x%p,%u,0x%lx,%u, EAGAIN.\n",
878 			csk, csk->state, csk->flags, csk->tid);
879 		err = -EAGAIN;
880 		goto out_err;
881 	}
882 
883 	if (csk->err) {
884 		log_debug(1 << CXGBI_DBG_PDU_TX,
885 			"csk 0x%p,%u,0x%lx,%u, EPIPE %d.\n",
886 			csk, csk->state, csk->flags, csk->tid, csk->err);
887 		err = -EPIPE;
888 		goto out_err;
889 	}
890 
891 	if (csk->write_seq - csk->snd_una >= cdev->snd_win) {
892 		log_debug(1 << CXGBI_DBG_PDU_TX,
893 			"csk 0x%p,%u,0x%lx,%u, FULL %u-%u >= %u.\n",
894 			csk, csk->state, csk->flags, csk->tid, csk->write_seq,
895 			csk->snd_una, cdev->snd_win);
896 		err = -ENOBUFS;
897 		goto out_err;
898 	}
899 
900 	while (skb) {
901 		int frags = skb_shinfo(skb)->nr_frags +
902 				(skb->len != skb->data_len);
903 
904 		if (unlikely(skb_headroom(skb) < cdev->skb_tx_rsvd)) {
905 			pr_err("csk 0x%p, skb head %u < %u.\n",
906 				csk, skb_headroom(skb), cdev->skb_tx_rsvd);
907 			err = -EINVAL;
908 			goto out_err;
909 		}
910 
911 		if (frags >= SKB_WR_LIST_SIZE) {
912 			pr_err("csk 0x%p, frags %d, %u,%u >%u.\n",
913 				csk, skb_shinfo(skb)->nr_frags, skb->len,
914 				skb->data_len, (uint)(SKB_WR_LIST_SIZE));
915 			err = -EINVAL;
916 			goto out_err;
917 		}
918 
919 		next = skb->next;
920 		skb->next = NULL;
921 		cxgbi_skcb_set_flag(skb, SKCBF_TX_NEED_HDR);
922 		cxgbi_sock_skb_entail(csk, skb);
923 		copied += skb->len;
924 		csk->write_seq += skb->len +
925 				cxgbi_ulp_extra_len(cxgbi_skcb_ulp_mode(skb));
926 		skb = next;
927 	}
928 done:
929 	if (likely(skb_queue_len(&csk->write_queue)))
930 		cdev->csk_push_tx_frames(csk, 1);
931 	spin_unlock_bh(&csk->lock);
932 	return copied;
933 
934 out_err:
935 	if (copied == 0 && err == -EPIPE)
936 		copied = csk->err ? csk->err : -EPIPE;
937 	else
938 		copied = err;
939 	goto done;
940 }
941 
942 /*
943  * Direct Data Placement -
944  * Directly place the iSCSI Data-In or Data-Out PDU's payload into pre-posted
945  * final destination host-memory buffers based on the Initiator Task Tag (ITT)
946  * in Data-In or Target Task Tag (TTT) in Data-Out PDUs.
947  * The host memory address is programmed into h/w in the format of pagepod
948  * entries.
949  * The location of the pagepod entry is encoded into ddp tag which is used as
950  * the base for ITT/TTT.
951  */
952 
953 static unsigned char ddp_page_order[DDP_PGIDX_MAX] = {0, 1, 2, 4};
954 static unsigned char ddp_page_shift[DDP_PGIDX_MAX] = {12, 13, 14, 16};
955 static unsigned char page_idx = DDP_PGIDX_MAX;
956 
957 static unsigned char sw_tag_idx_bits;
958 static unsigned char sw_tag_age_bits;
959 
960 /*
961  * Direct-Data Placement page size adjustment
962  */
963 static int ddp_adjust_page_table(void)
964 {
965 	int i;
966 	unsigned int base_order, order;
967 
968 	if (PAGE_SIZE < (1UL << ddp_page_shift[0])) {
969 		pr_info("PAGE_SIZE 0x%lx too small, min 0x%lx\n",
970 			PAGE_SIZE, 1UL << ddp_page_shift[0]);
971 		return -EINVAL;
972 	}
973 
974 	base_order = get_order(1UL << ddp_page_shift[0]);
975 	order = get_order(1UL << PAGE_SHIFT);
976 
977 	for (i = 0; i < DDP_PGIDX_MAX; i++) {
978 		/* first is the kernel page size, then just doubling */
979 		ddp_page_order[i] = order - base_order + i;
980 		ddp_page_shift[i] = PAGE_SHIFT + i;
981 	}
982 	return 0;
983 }
984 
985 static int ddp_find_page_index(unsigned long pgsz)
986 {
987 	int i;
988 
989 	for (i = 0; i < DDP_PGIDX_MAX; i++) {
990 		if (pgsz == (1UL << ddp_page_shift[i]))
991 			return i;
992 	}
993 	pr_info("ddp page size %lu not supported.\n", pgsz);
994 	return DDP_PGIDX_MAX;
995 }
996 
997 static void ddp_setup_host_page_size(void)
998 {
999 	if (page_idx == DDP_PGIDX_MAX) {
1000 		page_idx = ddp_find_page_index(PAGE_SIZE);
1001 
1002 		if (page_idx == DDP_PGIDX_MAX) {
1003 			pr_info("system PAGE %lu, update hw.\n", PAGE_SIZE);
1004 			if (ddp_adjust_page_table() < 0) {
1005 				pr_info("PAGE %lu, disable ddp.\n", PAGE_SIZE);
1006 				return;
1007 			}
1008 			page_idx = ddp_find_page_index(PAGE_SIZE);
1009 		}
1010 		pr_info("system PAGE %lu, ddp idx %u.\n", PAGE_SIZE, page_idx);
1011 	}
1012 }
1013 
1014 void cxgbi_ddp_page_size_factor(int *pgsz_factor)
1015 {
1016 	int i;
1017 
1018 	for (i = 0; i < DDP_PGIDX_MAX; i++)
1019 		pgsz_factor[i] = ddp_page_order[i];
1020 }
1021 EXPORT_SYMBOL_GPL(cxgbi_ddp_page_size_factor);
1022 
1023 /*
1024  * DDP setup & teardown
1025  */
1026 
1027 void cxgbi_ddp_ppod_set(struct cxgbi_pagepod *ppod,
1028 			struct cxgbi_pagepod_hdr *hdr,
1029 			struct cxgbi_gather_list *gl, unsigned int gidx)
1030 {
1031 	int i;
1032 
1033 	memcpy(ppod, hdr, sizeof(*hdr));
1034 	for (i = 0; i < (PPOD_PAGES_MAX + 1); i++, gidx++) {
1035 		ppod->addr[i] = gidx < gl->nelem ?
1036 				cpu_to_be64(gl->phys_addr[gidx]) : 0ULL;
1037 	}
1038 }
1039 EXPORT_SYMBOL_GPL(cxgbi_ddp_ppod_set);
1040 
1041 void cxgbi_ddp_ppod_clear(struct cxgbi_pagepod *ppod)
1042 {
1043 	memset(ppod, 0, sizeof(*ppod));
1044 }
1045 EXPORT_SYMBOL_GPL(cxgbi_ddp_ppod_clear);
1046 
1047 static inline int ddp_find_unused_entries(struct cxgbi_ddp_info *ddp,
1048 					unsigned int start, unsigned int max,
1049 					unsigned int count,
1050 					struct cxgbi_gather_list *gl)
1051 {
1052 	unsigned int i, j, k;
1053 
1054 	/*  not enough entries */
1055 	if ((max - start) < count) {
1056 		log_debug(1 << CXGBI_DBG_DDP,
1057 			"NOT enough entries %u+%u < %u.\n", start, count, max);
1058 		return -EBUSY;
1059 	}
1060 
1061 	max -= count;
1062 	spin_lock(&ddp->map_lock);
1063 	for (i = start; i < max;) {
1064 		for (j = 0, k = i; j < count; j++, k++) {
1065 			if (ddp->gl_map[k])
1066 				break;
1067 		}
1068 		if (j == count) {
1069 			for (j = 0, k = i; j < count; j++, k++)
1070 				ddp->gl_map[k] = gl;
1071 			spin_unlock(&ddp->map_lock);
1072 			return i;
1073 		}
1074 		i += j + 1;
1075 	}
1076 	spin_unlock(&ddp->map_lock);
1077 	log_debug(1 << CXGBI_DBG_DDP,
1078 		"NO suitable entries %u available.\n", count);
1079 	return -EBUSY;
1080 }
1081 
1082 static inline void ddp_unmark_entries(struct cxgbi_ddp_info *ddp,
1083 						int start, int count)
1084 {
1085 	spin_lock(&ddp->map_lock);
1086 	memset(&ddp->gl_map[start], 0,
1087 		count * sizeof(struct cxgbi_gather_list *));
1088 	spin_unlock(&ddp->map_lock);
1089 }
1090 
1091 static inline void ddp_gl_unmap(struct pci_dev *pdev,
1092 					struct cxgbi_gather_list *gl)
1093 {
1094 	int i;
1095 
1096 	for (i = 0; i < gl->nelem; i++)
1097 		dma_unmap_page(&pdev->dev, gl->phys_addr[i], PAGE_SIZE,
1098 				PCI_DMA_FROMDEVICE);
1099 }
1100 
1101 static inline int ddp_gl_map(struct pci_dev *pdev,
1102 				    struct cxgbi_gather_list *gl)
1103 {
1104 	int i;
1105 
1106 	for (i = 0; i < gl->nelem; i++) {
1107 		gl->phys_addr[i] = dma_map_page(&pdev->dev, gl->pages[i], 0,
1108 						PAGE_SIZE,
1109 						PCI_DMA_FROMDEVICE);
1110 		if (unlikely(dma_mapping_error(&pdev->dev, gl->phys_addr[i]))) {
1111 			log_debug(1 << CXGBI_DBG_DDP,
1112 				"page %d 0x%p, 0x%p dma mapping err.\n",
1113 				i, gl->pages[i], pdev);
1114 			goto unmap;
1115 		}
1116 	}
1117 	return i;
1118 unmap:
1119 	if (i) {
1120 		unsigned int nelem = gl->nelem;
1121 
1122 		gl->nelem = i;
1123 		ddp_gl_unmap(pdev, gl);
1124 		gl->nelem = nelem;
1125 	}
1126 	return -EINVAL;
1127 }
1128 
1129 static void ddp_release_gl(struct cxgbi_gather_list *gl,
1130 				  struct pci_dev *pdev)
1131 {
1132 	ddp_gl_unmap(pdev, gl);
1133 	kfree(gl);
1134 }
1135 
1136 static struct cxgbi_gather_list *ddp_make_gl(unsigned int xferlen,
1137 						    struct scatterlist *sgl,
1138 						    unsigned int sgcnt,
1139 						    struct pci_dev *pdev,
1140 						    gfp_t gfp)
1141 {
1142 	struct cxgbi_gather_list *gl;
1143 	struct scatterlist *sg = sgl;
1144 	struct page *sgpage = sg_page(sg);
1145 	unsigned int sglen = sg->length;
1146 	unsigned int sgoffset = sg->offset;
1147 	unsigned int npages = (xferlen + sgoffset + PAGE_SIZE - 1) >>
1148 				PAGE_SHIFT;
1149 	int i = 1, j = 0;
1150 
1151 	if (xferlen < DDP_THRESHOLD) {
1152 		log_debug(1 << CXGBI_DBG_DDP,
1153 			"xfer %u < threshold %u, no ddp.\n",
1154 			xferlen, DDP_THRESHOLD);
1155 		return NULL;
1156 	}
1157 
1158 	gl = kzalloc(sizeof(struct cxgbi_gather_list) +
1159 		     npages * (sizeof(dma_addr_t) +
1160 		     sizeof(struct page *)), gfp);
1161 	if (!gl) {
1162 		log_debug(1 << CXGBI_DBG_DDP,
1163 			"xfer %u, %u pages, OOM.\n", xferlen, npages);
1164 		return NULL;
1165 	}
1166 
1167 	 log_debug(1 << CXGBI_DBG_DDP,
1168 		"xfer %u, sgl %u, gl max %u.\n", xferlen, sgcnt, npages);
1169 
1170 	gl->pages = (struct page **)&gl->phys_addr[npages];
1171 	gl->nelem = npages;
1172 	gl->length = xferlen;
1173 	gl->offset = sgoffset;
1174 	gl->pages[0] = sgpage;
1175 
1176 	for (i = 1, sg = sg_next(sgl), j = 0; i < sgcnt;
1177 		i++, sg = sg_next(sg)) {
1178 		struct page *page = sg_page(sg);
1179 
1180 		if (sgpage == page && sg->offset == sgoffset + sglen)
1181 			sglen += sg->length;
1182 		else {
1183 			/*  make sure the sgl is fit for ddp:
1184 			 *  each has the same page size, and
1185 			 *  all of the middle pages are used completely
1186 			 */
1187 			if ((j && sgoffset) || ((i != sgcnt - 1) &&
1188 			    ((sglen + sgoffset) & ~PAGE_MASK))) {
1189 				log_debug(1 << CXGBI_DBG_DDP,
1190 					"page %d/%u, %u + %u.\n",
1191 					i, sgcnt, sgoffset, sglen);
1192 				goto error_out;
1193 			}
1194 
1195 			j++;
1196 			if (j == gl->nelem || sg->offset) {
1197 				log_debug(1 << CXGBI_DBG_DDP,
1198 					"page %d/%u, offset %u.\n",
1199 					j, gl->nelem, sg->offset);
1200 				goto error_out;
1201 			}
1202 			gl->pages[j] = page;
1203 			sglen = sg->length;
1204 			sgoffset = sg->offset;
1205 			sgpage = page;
1206 		}
1207 	}
1208 	gl->nelem = ++j;
1209 
1210 	if (ddp_gl_map(pdev, gl) < 0)
1211 		goto error_out;
1212 
1213 	return gl;
1214 
1215 error_out:
1216 	kfree(gl);
1217 	return NULL;
1218 }
1219 
1220 static void ddp_tag_release(struct cxgbi_hba *chba, u32 tag)
1221 {
1222 	struct cxgbi_device *cdev = chba->cdev;
1223 	struct cxgbi_ddp_info *ddp = cdev->ddp;
1224 	u32 idx;
1225 
1226 	idx = (tag >> PPOD_IDX_SHIFT) & ddp->idx_mask;
1227 	if (idx < ddp->nppods) {
1228 		struct cxgbi_gather_list *gl = ddp->gl_map[idx];
1229 		unsigned int npods;
1230 
1231 		if (!gl || !gl->nelem) {
1232 			pr_warn("tag 0x%x, idx %u, gl 0x%p, %u.\n",
1233 				tag, idx, gl, gl ? gl->nelem : 0);
1234 			return;
1235 		}
1236 		npods = (gl->nelem + PPOD_PAGES_MAX - 1) >> PPOD_PAGES_SHIFT;
1237 		log_debug(1 << CXGBI_DBG_DDP,
1238 			"tag 0x%x, release idx %u, npods %u.\n",
1239 			tag, idx, npods);
1240 		cdev->csk_ddp_clear(chba, tag, idx, npods);
1241 		ddp_unmark_entries(ddp, idx, npods);
1242 		ddp_release_gl(gl, ddp->pdev);
1243 	} else
1244 		pr_warn("tag 0x%x, idx %u > max %u.\n", tag, idx, ddp->nppods);
1245 }
1246 
1247 static int ddp_tag_reserve(struct cxgbi_sock *csk, unsigned int tid,
1248 			   u32 sw_tag, u32 *tagp, struct cxgbi_gather_list *gl,
1249 			   gfp_t gfp)
1250 {
1251 	struct cxgbi_device *cdev = csk->cdev;
1252 	struct cxgbi_ddp_info *ddp = cdev->ddp;
1253 	struct cxgbi_tag_format *tformat = &cdev->tag_format;
1254 	struct cxgbi_pagepod_hdr hdr;
1255 	unsigned int npods;
1256 	int idx = -1;
1257 	int err = -ENOMEM;
1258 	u32 tag;
1259 
1260 	npods = (gl->nelem + PPOD_PAGES_MAX - 1) >> PPOD_PAGES_SHIFT;
1261 	if (ddp->idx_last == ddp->nppods)
1262 		idx = ddp_find_unused_entries(ddp, 0, ddp->nppods,
1263 							npods, gl);
1264 	else {
1265 		idx = ddp_find_unused_entries(ddp, ddp->idx_last + 1,
1266 							ddp->nppods, npods,
1267 							gl);
1268 		if (idx < 0 && ddp->idx_last >= npods) {
1269 			idx = ddp_find_unused_entries(ddp, 0,
1270 				min(ddp->idx_last + npods, ddp->nppods),
1271 							npods, gl);
1272 		}
1273 	}
1274 	if (idx < 0) {
1275 		log_debug(1 << CXGBI_DBG_DDP,
1276 			"xferlen %u, gl %u, npods %u NO DDP.\n",
1277 			gl->length, gl->nelem, npods);
1278 		return idx;
1279 	}
1280 
1281 	tag = cxgbi_ddp_tag_base(tformat, sw_tag);
1282 	tag |= idx << PPOD_IDX_SHIFT;
1283 
1284 	hdr.rsvd = 0;
1285 	hdr.vld_tid = htonl(PPOD_VALID_FLAG | PPOD_TID(tid));
1286 	hdr.pgsz_tag_clr = htonl(tag & ddp->rsvd_tag_mask);
1287 	hdr.max_offset = htonl(gl->length);
1288 	hdr.page_offset = htonl(gl->offset);
1289 
1290 	err = cdev->csk_ddp_set(csk, &hdr, idx, npods, gl);
1291 	if (err < 0)
1292 		goto unmark_entries;
1293 
1294 	ddp->idx_last = idx;
1295 	log_debug(1 << CXGBI_DBG_DDP,
1296 		"xfer %u, gl %u,%u, tid 0x%x, tag 0x%x->0x%x(%u,%u).\n",
1297 		gl->length, gl->nelem, gl->offset, tid, sw_tag, tag, idx,
1298 		npods);
1299 	*tagp = tag;
1300 	return 0;
1301 
1302 unmark_entries:
1303 	ddp_unmark_entries(ddp, idx, npods);
1304 	return err;
1305 }
1306 
1307 int cxgbi_ddp_reserve(struct cxgbi_sock *csk, unsigned int *tagp,
1308 			unsigned int sw_tag, unsigned int xferlen,
1309 			struct scatterlist *sgl, unsigned int sgcnt, gfp_t gfp)
1310 {
1311 	struct cxgbi_device *cdev = csk->cdev;
1312 	struct cxgbi_tag_format *tformat = &cdev->tag_format;
1313 	struct cxgbi_gather_list *gl;
1314 	int err;
1315 
1316 	if (page_idx >= DDP_PGIDX_MAX || !cdev->ddp ||
1317 	    xferlen < DDP_THRESHOLD) {
1318 		log_debug(1 << CXGBI_DBG_DDP,
1319 			"pgidx %u, xfer %u, NO ddp.\n", page_idx, xferlen);
1320 		return -EINVAL;
1321 	}
1322 
1323 	if (!cxgbi_sw_tag_usable(tformat, sw_tag)) {
1324 		log_debug(1 << CXGBI_DBG_DDP,
1325 			"sw_tag 0x%x NOT usable.\n", sw_tag);
1326 		return -EINVAL;
1327 	}
1328 
1329 	gl = ddp_make_gl(xferlen, sgl, sgcnt, cdev->pdev, gfp);
1330 	if (!gl)
1331 		return -ENOMEM;
1332 
1333 	err = ddp_tag_reserve(csk, csk->tid, sw_tag, tagp, gl, gfp);
1334 	if (err < 0)
1335 		ddp_release_gl(gl, cdev->pdev);
1336 
1337 	return err;
1338 }
1339 
1340 static void ddp_destroy(struct kref *kref)
1341 {
1342 	struct cxgbi_ddp_info *ddp = container_of(kref,
1343 						struct cxgbi_ddp_info,
1344 						refcnt);
1345 	struct cxgbi_device *cdev = ddp->cdev;
1346 	int i = 0;
1347 
1348 	pr_info("kref 0, destroy ddp 0x%p, cdev 0x%p.\n", ddp, cdev);
1349 
1350 	while (i < ddp->nppods) {
1351 		struct cxgbi_gather_list *gl = ddp->gl_map[i];
1352 
1353 		if (gl) {
1354 			int npods = (gl->nelem + PPOD_PAGES_MAX - 1)
1355 					>> PPOD_PAGES_SHIFT;
1356 			pr_info("cdev 0x%p, ddp %d + %d.\n", cdev, i, npods);
1357 			kfree(gl);
1358 			i += npods;
1359 		} else
1360 			i++;
1361 	}
1362 	cxgbi_free_big_mem(ddp);
1363 }
1364 
1365 int cxgbi_ddp_cleanup(struct cxgbi_device *cdev)
1366 {
1367 	struct cxgbi_ddp_info *ddp = cdev->ddp;
1368 
1369 	log_debug(1 << CXGBI_DBG_DDP,
1370 		"cdev 0x%p, release ddp 0x%p.\n", cdev, ddp);
1371 	cdev->ddp = NULL;
1372 	if (ddp)
1373 		return kref_put(&ddp->refcnt, ddp_destroy);
1374 	return 0;
1375 }
1376 EXPORT_SYMBOL_GPL(cxgbi_ddp_cleanup);
1377 
1378 int cxgbi_ddp_init(struct cxgbi_device *cdev,
1379 		   unsigned int llimit, unsigned int ulimit,
1380 		   unsigned int max_txsz, unsigned int max_rxsz)
1381 {
1382 	struct cxgbi_ddp_info *ddp;
1383 	unsigned int ppmax, bits;
1384 
1385 	ppmax = (ulimit - llimit + 1) >> PPOD_SIZE_SHIFT;
1386 	bits = __ilog2_u32(ppmax) + 1;
1387 	if (bits > PPOD_IDX_MAX_SIZE)
1388 		bits = PPOD_IDX_MAX_SIZE;
1389 	ppmax = (1 << (bits - 1)) - 1;
1390 
1391 	ddp = cxgbi_alloc_big_mem(sizeof(struct cxgbi_ddp_info) +
1392 				ppmax * (sizeof(struct cxgbi_gather_list *) +
1393 					 sizeof(struct sk_buff *)),
1394 				GFP_KERNEL);
1395 	if (!ddp) {
1396 		pr_warn("cdev 0x%p, ddp ppmax %u OOM.\n", cdev, ppmax);
1397 		return -ENOMEM;
1398 	}
1399 	ddp->gl_map = (struct cxgbi_gather_list **)(ddp + 1);
1400 	cdev->ddp = ddp;
1401 
1402 	spin_lock_init(&ddp->map_lock);
1403 	kref_init(&ddp->refcnt);
1404 
1405 	ddp->cdev = cdev;
1406 	ddp->pdev = cdev->pdev;
1407 	ddp->llimit = llimit;
1408 	ddp->ulimit = ulimit;
1409 	ddp->max_txsz = min_t(unsigned int, max_txsz, ULP2_MAX_PKT_SIZE);
1410 	ddp->max_rxsz = min_t(unsigned int, max_rxsz, ULP2_MAX_PKT_SIZE);
1411 	ddp->nppods = ppmax;
1412 	ddp->idx_last = ppmax;
1413 	ddp->idx_bits = bits;
1414 	ddp->idx_mask = (1 << bits) - 1;
1415 	ddp->rsvd_tag_mask = (1 << (bits + PPOD_IDX_SHIFT)) - 1;
1416 
1417 	cdev->tag_format.sw_bits = sw_tag_idx_bits + sw_tag_age_bits;
1418 	cdev->tag_format.rsvd_bits = ddp->idx_bits;
1419 	cdev->tag_format.rsvd_shift = PPOD_IDX_SHIFT;
1420 	cdev->tag_format.rsvd_mask = (1 << cdev->tag_format.rsvd_bits) - 1;
1421 
1422 	pr_info("%s tag format, sw %u, rsvd %u,%u, mask 0x%x.\n",
1423 		cdev->ports[0]->name, cdev->tag_format.sw_bits,
1424 		cdev->tag_format.rsvd_bits, cdev->tag_format.rsvd_shift,
1425 		cdev->tag_format.rsvd_mask);
1426 
1427 	cdev->tx_max_size = min_t(unsigned int, ULP2_MAX_PDU_PAYLOAD,
1428 				ddp->max_txsz - ISCSI_PDU_NONPAYLOAD_LEN);
1429 	cdev->rx_max_size = min_t(unsigned int, ULP2_MAX_PDU_PAYLOAD,
1430 				ddp->max_rxsz - ISCSI_PDU_NONPAYLOAD_LEN);
1431 
1432 	log_debug(1 << CXGBI_DBG_DDP,
1433 		"%s max payload size: %u/%u, %u/%u.\n",
1434 		cdev->ports[0]->name, cdev->tx_max_size, ddp->max_txsz,
1435 		cdev->rx_max_size, ddp->max_rxsz);
1436 	return 0;
1437 }
1438 EXPORT_SYMBOL_GPL(cxgbi_ddp_init);
1439 
1440 /*
1441  * APIs interacting with open-iscsi libraries
1442  */
1443 
1444 static unsigned char padding[4];
1445 
1446 static void task_release_itt(struct iscsi_task *task, itt_t hdr_itt)
1447 {
1448 	struct scsi_cmnd *sc = task->sc;
1449 	struct iscsi_tcp_conn *tcp_conn = task->conn->dd_data;
1450 	struct cxgbi_conn *cconn = tcp_conn->dd_data;
1451 	struct cxgbi_hba *chba = cconn->chba;
1452 	struct cxgbi_tag_format *tformat = &chba->cdev->tag_format;
1453 	u32 tag = ntohl((__force u32)hdr_itt);
1454 
1455 	log_debug(1 << CXGBI_DBG_DDP,
1456 		   "cdev 0x%p, release tag 0x%x.\n", chba->cdev, tag);
1457 	if (sc &&
1458 	    (scsi_bidi_cmnd(sc) || sc->sc_data_direction == DMA_FROM_DEVICE) &&
1459 	    cxgbi_is_ddp_tag(tformat, tag))
1460 		ddp_tag_release(chba, tag);
1461 }
1462 
1463 static int task_reserve_itt(struct iscsi_task *task, itt_t *hdr_itt)
1464 {
1465 	struct scsi_cmnd *sc = task->sc;
1466 	struct iscsi_conn *conn = task->conn;
1467 	struct iscsi_session *sess = conn->session;
1468 	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1469 	struct cxgbi_conn *cconn = tcp_conn->dd_data;
1470 	struct cxgbi_hba *chba = cconn->chba;
1471 	struct cxgbi_tag_format *tformat = &chba->cdev->tag_format;
1472 	u32 sw_tag = (sess->age << cconn->task_idx_bits) | task->itt;
1473 	u32 tag = 0;
1474 	int err = -EINVAL;
1475 
1476 	if (sc &&
1477 	    (scsi_bidi_cmnd(sc) || sc->sc_data_direction == DMA_FROM_DEVICE)) {
1478 		err = cxgbi_ddp_reserve(cconn->cep->csk, &tag, sw_tag,
1479 					scsi_in(sc)->length,
1480 					scsi_in(sc)->table.sgl,
1481 					scsi_in(sc)->table.nents,
1482 					GFP_ATOMIC);
1483 		if (err < 0)
1484 			log_debug(1 << CXGBI_DBG_DDP,
1485 				"csk 0x%p, R task 0x%p, %u,%u, no ddp.\n",
1486 				cconn->cep->csk, task, scsi_in(sc)->length,
1487 				scsi_in(sc)->table.nents);
1488 	}
1489 
1490 	if (err < 0)
1491 		tag = cxgbi_set_non_ddp_tag(tformat, sw_tag);
1492 	/*  the itt need to sent in big-endian order */
1493 	*hdr_itt = (__force itt_t)htonl(tag);
1494 
1495 	log_debug(1 << CXGBI_DBG_DDP,
1496 		"cdev 0x%p, task 0x%p, 0x%x(0x%x,0x%x)->0x%x/0x%x.\n",
1497 		chba->cdev, task, sw_tag, task->itt, sess->age, tag, *hdr_itt);
1498 	return 0;
1499 }
1500 
1501 void cxgbi_parse_pdu_itt(struct iscsi_conn *conn, itt_t itt, int *idx, int *age)
1502 {
1503 	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1504 	struct cxgbi_conn *cconn = tcp_conn->dd_data;
1505 	struct cxgbi_device *cdev = cconn->chba->cdev;
1506 	u32 tag = ntohl((__force u32) itt);
1507 	u32 sw_bits;
1508 
1509 	sw_bits = cxgbi_tag_nonrsvd_bits(&cdev->tag_format, tag);
1510 	if (idx)
1511 		*idx = sw_bits & ((1 << cconn->task_idx_bits) - 1);
1512 	if (age)
1513 		*age = (sw_bits >> cconn->task_idx_bits) & ISCSI_AGE_MASK;
1514 
1515 	log_debug(1 << CXGBI_DBG_DDP,
1516 		"cdev 0x%p, tag 0x%x/0x%x, -> 0x%x(0x%x,0x%x).\n",
1517 		cdev, tag, itt, sw_bits, idx ? *idx : 0xFFFFF,
1518 		age ? *age : 0xFF);
1519 }
1520 EXPORT_SYMBOL_GPL(cxgbi_parse_pdu_itt);
1521 
1522 void cxgbi_conn_tx_open(struct cxgbi_sock *csk)
1523 {
1524 	struct iscsi_conn *conn = csk->user_data;
1525 
1526 	if (conn) {
1527 		log_debug(1 << CXGBI_DBG_SOCK,
1528 			"csk 0x%p, cid %d.\n", csk, conn->id);
1529 		iscsi_conn_queue_work(conn);
1530 	}
1531 }
1532 EXPORT_SYMBOL_GPL(cxgbi_conn_tx_open);
1533 
1534 /*
1535  * pdu receive, interact with libiscsi_tcp
1536  */
1537 static inline int read_pdu_skb(struct iscsi_conn *conn,
1538 			       struct sk_buff *skb,
1539 			       unsigned int offset,
1540 			       int offloaded)
1541 {
1542 	int status = 0;
1543 	int bytes_read;
1544 
1545 	bytes_read = iscsi_tcp_recv_skb(conn, skb, offset, offloaded, &status);
1546 	switch (status) {
1547 	case ISCSI_TCP_CONN_ERR:
1548 		pr_info("skb 0x%p, off %u, %d, TCP_ERR.\n",
1549 			  skb, offset, offloaded);
1550 		return -EIO;
1551 	case ISCSI_TCP_SUSPENDED:
1552 		log_debug(1 << CXGBI_DBG_PDU_RX,
1553 			"skb 0x%p, off %u, %d, TCP_SUSPEND, rc %d.\n",
1554 			skb, offset, offloaded, bytes_read);
1555 		/* no transfer - just have caller flush queue */
1556 		return bytes_read;
1557 	case ISCSI_TCP_SKB_DONE:
1558 		pr_info("skb 0x%p, off %u, %d, TCP_SKB_DONE.\n",
1559 			skb, offset, offloaded);
1560 		/*
1561 		 * pdus should always fit in the skb and we should get
1562 		 * segment done notifcation.
1563 		 */
1564 		iscsi_conn_printk(KERN_ERR, conn, "Invalid pdu or skb.");
1565 		return -EFAULT;
1566 	case ISCSI_TCP_SEGMENT_DONE:
1567 		log_debug(1 << CXGBI_DBG_PDU_RX,
1568 			"skb 0x%p, off %u, %d, TCP_SEG_DONE, rc %d.\n",
1569 			skb, offset, offloaded, bytes_read);
1570 		return bytes_read;
1571 	default:
1572 		pr_info("skb 0x%p, off %u, %d, invalid status %d.\n",
1573 			skb, offset, offloaded, status);
1574 		return -EINVAL;
1575 	}
1576 }
1577 
1578 static int skb_read_pdu_bhs(struct iscsi_conn *conn, struct sk_buff *skb)
1579 {
1580 	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1581 
1582 	log_debug(1 << CXGBI_DBG_PDU_RX,
1583 		"conn 0x%p, skb 0x%p, len %u, flag 0x%lx.\n",
1584 		conn, skb, skb->len, cxgbi_skcb_flags(skb));
1585 
1586 	if (!iscsi_tcp_recv_segment_is_hdr(tcp_conn)) {
1587 		pr_info("conn 0x%p, skb 0x%p, not hdr.\n", conn, skb);
1588 		iscsi_conn_failure(conn, ISCSI_ERR_PROTO);
1589 		return -EIO;
1590 	}
1591 
1592 	if (conn->hdrdgst_en &&
1593 	    cxgbi_skcb_test_flag(skb, SKCBF_RX_HCRC_ERR)) {
1594 		pr_info("conn 0x%p, skb 0x%p, hcrc.\n", conn, skb);
1595 		iscsi_conn_failure(conn, ISCSI_ERR_HDR_DGST);
1596 		return -EIO;
1597 	}
1598 
1599 	return read_pdu_skb(conn, skb, 0, 0);
1600 }
1601 
1602 static int skb_read_pdu_data(struct iscsi_conn *conn, struct sk_buff *lskb,
1603 			     struct sk_buff *skb, unsigned int offset)
1604 {
1605 	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1606 	bool offloaded = 0;
1607 	int opcode = tcp_conn->in.hdr->opcode & ISCSI_OPCODE_MASK;
1608 
1609 	log_debug(1 << CXGBI_DBG_PDU_RX,
1610 		"conn 0x%p, skb 0x%p, len %u, flag 0x%lx.\n",
1611 		conn, skb, skb->len, cxgbi_skcb_flags(skb));
1612 
1613 	if (conn->datadgst_en &&
1614 	    cxgbi_skcb_test_flag(lskb, SKCBF_RX_DCRC_ERR)) {
1615 		pr_info("conn 0x%p, skb 0x%p, dcrc 0x%lx.\n",
1616 			conn, lskb, cxgbi_skcb_flags(lskb));
1617 		iscsi_conn_failure(conn, ISCSI_ERR_DATA_DGST);
1618 		return -EIO;
1619 	}
1620 
1621 	if (iscsi_tcp_recv_segment_is_hdr(tcp_conn))
1622 		return 0;
1623 
1624 	/* coalesced, add header digest length */
1625 	if (lskb == skb && conn->hdrdgst_en)
1626 		offset += ISCSI_DIGEST_SIZE;
1627 
1628 	if (cxgbi_skcb_test_flag(lskb, SKCBF_RX_DATA_DDPD))
1629 		offloaded = 1;
1630 
1631 	if (opcode == ISCSI_OP_SCSI_DATA_IN)
1632 		log_debug(1 << CXGBI_DBG_PDU_RX,
1633 			"skb 0x%p, op 0x%x, itt 0x%x, %u %s ddp'ed.\n",
1634 			skb, opcode, ntohl(tcp_conn->in.hdr->itt),
1635 			tcp_conn->in.datalen, offloaded ? "is" : "not");
1636 
1637 	return read_pdu_skb(conn, skb, offset, offloaded);
1638 }
1639 
1640 static void csk_return_rx_credits(struct cxgbi_sock *csk, int copied)
1641 {
1642 	struct cxgbi_device *cdev = csk->cdev;
1643 	int must_send;
1644 	u32 credits;
1645 
1646 	log_debug(1 << CXGBI_DBG_PDU_RX,
1647 		"csk 0x%p,%u,0x%lu,%u, seq %u, wup %u, thre %u, %u.\n",
1648 		csk, csk->state, csk->flags, csk->tid, csk->copied_seq,
1649 		csk->rcv_wup, cdev->rx_credit_thres,
1650 		cdev->rcv_win);
1651 
1652 	if (csk->state != CTP_ESTABLISHED)
1653 		return;
1654 
1655 	credits = csk->copied_seq - csk->rcv_wup;
1656 	if (unlikely(!credits))
1657 		return;
1658 	if (unlikely(cdev->rx_credit_thres == 0))
1659 		return;
1660 
1661 	must_send = credits + 16384 >= cdev->rcv_win;
1662 	if (must_send || credits >= cdev->rx_credit_thres)
1663 		csk->rcv_wup += cdev->csk_send_rx_credits(csk, credits);
1664 }
1665 
1666 void cxgbi_conn_pdu_ready(struct cxgbi_sock *csk)
1667 {
1668 	struct cxgbi_device *cdev = csk->cdev;
1669 	struct iscsi_conn *conn = csk->user_data;
1670 	struct sk_buff *skb;
1671 	unsigned int read = 0;
1672 	int err = 0;
1673 
1674 	log_debug(1 << CXGBI_DBG_PDU_RX,
1675 		"csk 0x%p, conn 0x%p.\n", csk, conn);
1676 
1677 	if (unlikely(!conn || conn->suspend_rx)) {
1678 		log_debug(1 << CXGBI_DBG_PDU_RX,
1679 			"csk 0x%p, conn 0x%p, id %d, suspend_rx %lu!\n",
1680 			csk, conn, conn ? conn->id : 0xFF,
1681 			conn ? conn->suspend_rx : 0xFF);
1682 		return;
1683 	}
1684 
1685 	while (!err) {
1686 		skb = skb_peek(&csk->receive_queue);
1687 		if (!skb ||
1688 		    !(cxgbi_skcb_test_flag(skb, SKCBF_RX_STATUS))) {
1689 			if (skb)
1690 				log_debug(1 << CXGBI_DBG_PDU_RX,
1691 					"skb 0x%p, NOT ready 0x%lx.\n",
1692 					skb, cxgbi_skcb_flags(skb));
1693 			break;
1694 		}
1695 		__skb_unlink(skb, &csk->receive_queue);
1696 
1697 		read += cxgbi_skcb_rx_pdulen(skb);
1698 		log_debug(1 << CXGBI_DBG_PDU_RX,
1699 			"csk 0x%p, skb 0x%p,%u,f 0x%lx, pdu len %u.\n",
1700 			csk, skb, skb->len, cxgbi_skcb_flags(skb),
1701 			cxgbi_skcb_rx_pdulen(skb));
1702 
1703 		if (cxgbi_skcb_test_flag(skb, SKCBF_RX_COALESCED)) {
1704 			err = skb_read_pdu_bhs(conn, skb);
1705 			if (err < 0) {
1706 				pr_err("coalesced bhs, csk 0x%p, skb 0x%p,%u, "
1707 					"f 0x%lx, plen %u.\n",
1708 					csk, skb, skb->len,
1709 					cxgbi_skcb_flags(skb),
1710 					cxgbi_skcb_rx_pdulen(skb));
1711 				goto skb_done;
1712 			}
1713 			err = skb_read_pdu_data(conn, skb, skb,
1714 						err + cdev->skb_rx_extra);
1715 			if (err < 0)
1716 				pr_err("coalesced data, csk 0x%p, skb 0x%p,%u, "
1717 					"f 0x%lx, plen %u.\n",
1718 					csk, skb, skb->len,
1719 					cxgbi_skcb_flags(skb),
1720 					cxgbi_skcb_rx_pdulen(skb));
1721 		} else {
1722 			err = skb_read_pdu_bhs(conn, skb);
1723 			if (err < 0) {
1724 				pr_err("bhs, csk 0x%p, skb 0x%p,%u, "
1725 					"f 0x%lx, plen %u.\n",
1726 					csk, skb, skb->len,
1727 					cxgbi_skcb_flags(skb),
1728 					cxgbi_skcb_rx_pdulen(skb));
1729 				goto skb_done;
1730 			}
1731 
1732 			if (cxgbi_skcb_test_flag(skb, SKCBF_RX_DATA)) {
1733 				struct sk_buff *dskb;
1734 
1735 				dskb = skb_peek(&csk->receive_queue);
1736 				if (!dskb) {
1737 					pr_err("csk 0x%p, skb 0x%p,%u, f 0x%lx,"
1738 						" plen %u, NO data.\n",
1739 						csk, skb, skb->len,
1740 						cxgbi_skcb_flags(skb),
1741 						cxgbi_skcb_rx_pdulen(skb));
1742 					err = -EIO;
1743 					goto skb_done;
1744 				}
1745 				__skb_unlink(dskb, &csk->receive_queue);
1746 
1747 				err = skb_read_pdu_data(conn, skb, dskb, 0);
1748 				if (err < 0)
1749 					pr_err("data, csk 0x%p, skb 0x%p,%u, "
1750 						"f 0x%lx, plen %u, dskb 0x%p,"
1751 						"%u.\n",
1752 						csk, skb, skb->len,
1753 						cxgbi_skcb_flags(skb),
1754 						cxgbi_skcb_rx_pdulen(skb),
1755 						dskb, dskb->len);
1756 				__kfree_skb(dskb);
1757 			} else
1758 				err = skb_read_pdu_data(conn, skb, skb, 0);
1759 		}
1760 skb_done:
1761 		__kfree_skb(skb);
1762 
1763 		if (err < 0)
1764 			break;
1765 	}
1766 
1767 	log_debug(1 << CXGBI_DBG_PDU_RX, "csk 0x%p, read %u.\n", csk, read);
1768 	if (read) {
1769 		csk->copied_seq += read;
1770 		csk_return_rx_credits(csk, read);
1771 		conn->rxdata_octets += read;
1772 	}
1773 
1774 	if (err < 0) {
1775 		pr_info("csk 0x%p, 0x%p, rx failed %d, read %u.\n",
1776 			csk, conn, err, read);
1777 		iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1778 	}
1779 }
1780 EXPORT_SYMBOL_GPL(cxgbi_conn_pdu_ready);
1781 
1782 static int sgl_seek_offset(struct scatterlist *sgl, unsigned int sgcnt,
1783 				unsigned int offset, unsigned int *off,
1784 				struct scatterlist **sgp)
1785 {
1786 	int i;
1787 	struct scatterlist *sg;
1788 
1789 	for_each_sg(sgl, sg, sgcnt, i) {
1790 		if (offset < sg->length) {
1791 			*off = offset;
1792 			*sgp = sg;
1793 			return 0;
1794 		}
1795 		offset -= sg->length;
1796 	}
1797 	return -EFAULT;
1798 }
1799 
1800 static int sgl_read_to_frags(struct scatterlist *sg, unsigned int sgoffset,
1801 				unsigned int dlen, struct page_frag *frags,
1802 				int frag_max)
1803 {
1804 	unsigned int datalen = dlen;
1805 	unsigned int sglen = sg->length - sgoffset;
1806 	struct page *page = sg_page(sg);
1807 	int i;
1808 
1809 	i = 0;
1810 	do {
1811 		unsigned int copy;
1812 
1813 		if (!sglen) {
1814 			sg = sg_next(sg);
1815 			if (!sg) {
1816 				pr_warn("sg %d NULL, len %u/%u.\n",
1817 					i, datalen, dlen);
1818 				return -EINVAL;
1819 			}
1820 			sgoffset = 0;
1821 			sglen = sg->length;
1822 			page = sg_page(sg);
1823 
1824 		}
1825 		copy = min(datalen, sglen);
1826 		if (i && page == frags[i - 1].page &&
1827 		    sgoffset + sg->offset ==
1828 			frags[i - 1].offset + frags[i - 1].size) {
1829 			frags[i - 1].size += copy;
1830 		} else {
1831 			if (i >= frag_max) {
1832 				pr_warn("too many pages %u, dlen %u.\n",
1833 					frag_max, dlen);
1834 				return -EINVAL;
1835 			}
1836 
1837 			frags[i].page = page;
1838 			frags[i].offset = sg->offset + sgoffset;
1839 			frags[i].size = copy;
1840 			i++;
1841 		}
1842 		datalen -= copy;
1843 		sgoffset += copy;
1844 		sglen -= copy;
1845 	} while (datalen);
1846 
1847 	return i;
1848 }
1849 
1850 int cxgbi_conn_alloc_pdu(struct iscsi_task *task, u8 opcode)
1851 {
1852 	struct iscsi_tcp_conn *tcp_conn = task->conn->dd_data;
1853 	struct cxgbi_conn *cconn = tcp_conn->dd_data;
1854 	struct cxgbi_device *cdev = cconn->chba->cdev;
1855 	struct iscsi_conn *conn = task->conn;
1856 	struct iscsi_tcp_task *tcp_task = task->dd_data;
1857 	struct cxgbi_task_data *tdata = iscsi_task_cxgbi_data(task);
1858 	struct scsi_cmnd *sc = task->sc;
1859 	int headroom = SKB_TX_ISCSI_PDU_HEADER_MAX;
1860 
1861 	tcp_task->dd_data = tdata;
1862 	task->hdr = NULL;
1863 
1864 	if (SKB_MAX_HEAD(cdev->skb_tx_rsvd) > (512 * MAX_SKB_FRAGS) &&
1865 	    (opcode == ISCSI_OP_SCSI_DATA_OUT ||
1866 	     (opcode == ISCSI_OP_SCSI_CMD &&
1867 	      (scsi_bidi_cmnd(sc) || sc->sc_data_direction == DMA_TO_DEVICE))))
1868 		/* data could goes into skb head */
1869 		headroom += min_t(unsigned int,
1870 				SKB_MAX_HEAD(cdev->skb_tx_rsvd),
1871 				conn->max_xmit_dlength);
1872 
1873 	tdata->skb = alloc_skb(cdev->skb_tx_rsvd + headroom, GFP_ATOMIC);
1874 	if (!tdata->skb) {
1875 		struct cxgbi_sock *csk = cconn->cep->csk;
1876 		struct net_device *ndev = cdev->ports[csk->port_id];
1877 		ndev->stats.tx_dropped++;
1878 		return -ENOMEM;
1879 	}
1880 
1881 	skb_reserve(tdata->skb, cdev->skb_tx_rsvd);
1882 	task->hdr = (struct iscsi_hdr *)tdata->skb->data;
1883 	task->hdr_max = SKB_TX_ISCSI_PDU_HEADER_MAX; /* BHS + AHS */
1884 
1885 	/* data_out uses scsi_cmd's itt */
1886 	if (opcode != ISCSI_OP_SCSI_DATA_OUT)
1887 		task_reserve_itt(task, &task->hdr->itt);
1888 
1889 	log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_PDU_TX,
1890 		"task 0x%p, op 0x%x, skb 0x%p,%u+%u/%u, itt 0x%x.\n",
1891 		task, opcode, tdata->skb, cdev->skb_tx_rsvd, headroom,
1892 		conn->max_xmit_dlength, ntohl(task->hdr->itt));
1893 
1894 	return 0;
1895 }
1896 EXPORT_SYMBOL_GPL(cxgbi_conn_alloc_pdu);
1897 
1898 static inline void tx_skb_setmode(struct sk_buff *skb, int hcrc, int dcrc)
1899 {
1900 	if (hcrc || dcrc) {
1901 		u8 submode = 0;
1902 
1903 		if (hcrc)
1904 			submode |= 1;
1905 		if (dcrc)
1906 			submode |= 2;
1907 		cxgbi_skcb_ulp_mode(skb) = (ULP2_MODE_ISCSI << 4) | submode;
1908 	} else
1909 		cxgbi_skcb_ulp_mode(skb) = 0;
1910 }
1911 
1912 int cxgbi_conn_init_pdu(struct iscsi_task *task, unsigned int offset,
1913 			      unsigned int count)
1914 {
1915 	struct iscsi_conn *conn = task->conn;
1916 	struct cxgbi_task_data *tdata = iscsi_task_cxgbi_data(task);
1917 	struct sk_buff *skb = tdata->skb;
1918 	unsigned int datalen = count;
1919 	int i, padlen = iscsi_padding(count);
1920 	struct page *pg;
1921 
1922 	log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_PDU_TX,
1923 		"task 0x%p,0x%p, skb 0x%p, 0x%x,0x%x,0x%x, %u+%u.\n",
1924 		task, task->sc, skb, (*skb->data) & ISCSI_OPCODE_MASK,
1925 		ntohl(task->cmdsn), ntohl(task->hdr->itt), offset, count);
1926 
1927 	skb_put(skb, task->hdr_len);
1928 	tx_skb_setmode(skb, conn->hdrdgst_en, datalen ? conn->datadgst_en : 0);
1929 	if (!count)
1930 		return 0;
1931 
1932 	if (task->sc) {
1933 		struct scsi_data_buffer *sdb = scsi_out(task->sc);
1934 		struct scatterlist *sg = NULL;
1935 		int err;
1936 
1937 		tdata->offset = offset;
1938 		tdata->count = count;
1939 		err = sgl_seek_offset(
1940 					sdb->table.sgl, sdb->table.nents,
1941 					tdata->offset, &tdata->sgoffset, &sg);
1942 		if (err < 0) {
1943 			pr_warn("tpdu, sgl %u, bad offset %u/%u.\n",
1944 				sdb->table.nents, tdata->offset, sdb->length);
1945 			return err;
1946 		}
1947 		err = sgl_read_to_frags(sg, tdata->sgoffset, tdata->count,
1948 					tdata->frags, MAX_PDU_FRAGS);
1949 		if (err < 0) {
1950 			pr_warn("tpdu, sgl %u, bad offset %u + %u.\n",
1951 				sdb->table.nents, tdata->offset, tdata->count);
1952 			return err;
1953 		}
1954 		tdata->nr_frags = err;
1955 
1956 		if (tdata->nr_frags > MAX_SKB_FRAGS ||
1957 		    (padlen && tdata->nr_frags == MAX_SKB_FRAGS)) {
1958 			char *dst = skb->data + task->hdr_len;
1959 			struct page_frag *frag = tdata->frags;
1960 
1961 			/* data fits in the skb's headroom */
1962 			for (i = 0; i < tdata->nr_frags; i++, frag++) {
1963 				char *src = kmap_atomic(frag->page);
1964 
1965 				memcpy(dst, src+frag->offset, frag->size);
1966 				dst += frag->size;
1967 				kunmap_atomic(src);
1968 			}
1969 			if (padlen) {
1970 				memset(dst, 0, padlen);
1971 				padlen = 0;
1972 			}
1973 			skb_put(skb, count + padlen);
1974 		} else {
1975 			/* data fit into frag_list */
1976 			for (i = 0; i < tdata->nr_frags; i++) {
1977 				__skb_fill_page_desc(skb, i,
1978 						tdata->frags[i].page,
1979 						tdata->frags[i].offset,
1980 						tdata->frags[i].size);
1981 				skb_frag_ref(skb, i);
1982 			}
1983 			skb_shinfo(skb)->nr_frags = tdata->nr_frags;
1984 			skb->len += count;
1985 			skb->data_len += count;
1986 			skb->truesize += count;
1987 		}
1988 
1989 	} else {
1990 		pg = virt_to_page(task->data);
1991 
1992 		get_page(pg);
1993 		skb_fill_page_desc(skb, 0, pg, offset_in_page(task->data),
1994 					count);
1995 		skb->len += count;
1996 		skb->data_len += count;
1997 		skb->truesize += count;
1998 	}
1999 
2000 	if (padlen) {
2001 		i = skb_shinfo(skb)->nr_frags;
2002 		skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags,
2003 				virt_to_page(padding), offset_in_page(padding),
2004 				padlen);
2005 
2006 		skb->data_len += padlen;
2007 		skb->truesize += padlen;
2008 		skb->len += padlen;
2009 	}
2010 
2011 	return 0;
2012 }
2013 EXPORT_SYMBOL_GPL(cxgbi_conn_init_pdu);
2014 
2015 int cxgbi_conn_xmit_pdu(struct iscsi_task *task)
2016 {
2017 	struct iscsi_tcp_conn *tcp_conn = task->conn->dd_data;
2018 	struct cxgbi_conn *cconn = tcp_conn->dd_data;
2019 	struct cxgbi_task_data *tdata = iscsi_task_cxgbi_data(task);
2020 	struct sk_buff *skb = tdata->skb;
2021 	unsigned int datalen;
2022 	int err;
2023 
2024 	if (!skb) {
2025 		log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_PDU_TX,
2026 			"task 0x%p, skb NULL.\n", task);
2027 		return 0;
2028 	}
2029 
2030 	datalen = skb->data_len;
2031 	tdata->skb = NULL;
2032 	err = cxgbi_sock_send_pdus(cconn->cep->csk, skb);
2033 	if (err > 0) {
2034 		int pdulen = err;
2035 
2036 		log_debug(1 << CXGBI_DBG_PDU_TX,
2037 			"task 0x%p,0x%p, skb 0x%p, len %u/%u, rv %d.\n",
2038 			task, task->sc, skb, skb->len, skb->data_len, err);
2039 
2040 		if (task->conn->hdrdgst_en)
2041 			pdulen += ISCSI_DIGEST_SIZE;
2042 
2043 		if (datalen && task->conn->datadgst_en)
2044 			pdulen += ISCSI_DIGEST_SIZE;
2045 
2046 		task->conn->txdata_octets += pdulen;
2047 		return 0;
2048 	}
2049 
2050 	if (err == -EAGAIN || err == -ENOBUFS) {
2051 		log_debug(1 << CXGBI_DBG_PDU_TX,
2052 			"task 0x%p, skb 0x%p, len %u/%u, %d EAGAIN.\n",
2053 			task, skb, skb->len, skb->data_len, err);
2054 		/* reset skb to send when we are called again */
2055 		tdata->skb = skb;
2056 		return err;
2057 	}
2058 
2059 	kfree_skb(skb);
2060 	log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_PDU_TX,
2061 		"itt 0x%x, skb 0x%p, len %u/%u, xmit err %d.\n",
2062 		task->itt, skb, skb->len, skb->data_len, err);
2063 	iscsi_conn_printk(KERN_ERR, task->conn, "xmit err %d.\n", err);
2064 	iscsi_conn_failure(task->conn, ISCSI_ERR_XMIT_FAILED);
2065 	return err;
2066 }
2067 EXPORT_SYMBOL_GPL(cxgbi_conn_xmit_pdu);
2068 
2069 void cxgbi_cleanup_task(struct iscsi_task *task)
2070 {
2071 	struct cxgbi_task_data *tdata = iscsi_task_cxgbi_data(task);
2072 
2073 	log_debug(1 << CXGBI_DBG_ISCSI,
2074 		"task 0x%p, skb 0x%p, itt 0x%x.\n",
2075 		task, tdata->skb, task->hdr_itt);
2076 
2077 	/*  never reached the xmit task callout */
2078 	if (tdata->skb)
2079 		__kfree_skb(tdata->skb);
2080 	memset(tdata, 0, sizeof(*tdata));
2081 
2082 	task_release_itt(task, task->hdr_itt);
2083 	iscsi_tcp_cleanup_task(task);
2084 }
2085 EXPORT_SYMBOL_GPL(cxgbi_cleanup_task);
2086 
2087 void cxgbi_get_conn_stats(struct iscsi_cls_conn *cls_conn,
2088 				struct iscsi_stats *stats)
2089 {
2090 	struct iscsi_conn *conn = cls_conn->dd_data;
2091 
2092 	stats->txdata_octets = conn->txdata_octets;
2093 	stats->rxdata_octets = conn->rxdata_octets;
2094 	stats->scsicmd_pdus = conn->scsicmd_pdus_cnt;
2095 	stats->dataout_pdus = conn->dataout_pdus_cnt;
2096 	stats->scsirsp_pdus = conn->scsirsp_pdus_cnt;
2097 	stats->datain_pdus = conn->datain_pdus_cnt;
2098 	stats->r2t_pdus = conn->r2t_pdus_cnt;
2099 	stats->tmfcmd_pdus = conn->tmfcmd_pdus_cnt;
2100 	stats->tmfrsp_pdus = conn->tmfrsp_pdus_cnt;
2101 	stats->digest_err = 0;
2102 	stats->timeout_err = 0;
2103 	stats->custom_length = 1;
2104 	strcpy(stats->custom[0].desc, "eh_abort_cnt");
2105 	stats->custom[0].value = conn->eh_abort_cnt;
2106 }
2107 EXPORT_SYMBOL_GPL(cxgbi_get_conn_stats);
2108 
2109 static int cxgbi_conn_max_xmit_dlength(struct iscsi_conn *conn)
2110 {
2111 	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
2112 	struct cxgbi_conn *cconn = tcp_conn->dd_data;
2113 	struct cxgbi_device *cdev = cconn->chba->cdev;
2114 	unsigned int headroom = SKB_MAX_HEAD(cdev->skb_tx_rsvd);
2115 	unsigned int max_def = 512 * MAX_SKB_FRAGS;
2116 	unsigned int max = max(max_def, headroom);
2117 
2118 	max = min(cconn->chba->cdev->tx_max_size, max);
2119 	if (conn->max_xmit_dlength)
2120 		conn->max_xmit_dlength = min(conn->max_xmit_dlength, max);
2121 	else
2122 		conn->max_xmit_dlength = max;
2123 	cxgbi_align_pdu_size(conn->max_xmit_dlength);
2124 
2125 	return 0;
2126 }
2127 
2128 static int cxgbi_conn_max_recv_dlength(struct iscsi_conn *conn)
2129 {
2130 	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
2131 	struct cxgbi_conn *cconn = tcp_conn->dd_data;
2132 	unsigned int max = cconn->chba->cdev->rx_max_size;
2133 
2134 	cxgbi_align_pdu_size(max);
2135 
2136 	if (conn->max_recv_dlength) {
2137 		if (conn->max_recv_dlength > max) {
2138 			pr_err("MaxRecvDataSegmentLength %u > %u.\n",
2139 				conn->max_recv_dlength, max);
2140 			return -EINVAL;
2141 		}
2142 		conn->max_recv_dlength = min(conn->max_recv_dlength, max);
2143 		cxgbi_align_pdu_size(conn->max_recv_dlength);
2144 	} else
2145 		conn->max_recv_dlength = max;
2146 
2147 	return 0;
2148 }
2149 
2150 int cxgbi_set_conn_param(struct iscsi_cls_conn *cls_conn,
2151 			enum iscsi_param param, char *buf, int buflen)
2152 {
2153 	struct iscsi_conn *conn = cls_conn->dd_data;
2154 	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
2155 	struct cxgbi_conn *cconn = tcp_conn->dd_data;
2156 	struct cxgbi_sock *csk = cconn->cep->csk;
2157 	int err;
2158 
2159 	log_debug(1 << CXGBI_DBG_ISCSI,
2160 		"cls_conn 0x%p, param %d, buf(%d) %s.\n",
2161 		cls_conn, param, buflen, buf);
2162 
2163 	switch (param) {
2164 	case ISCSI_PARAM_HDRDGST_EN:
2165 		err = iscsi_set_param(cls_conn, param, buf, buflen);
2166 		if (!err && conn->hdrdgst_en)
2167 			err = csk->cdev->csk_ddp_setup_digest(csk, csk->tid,
2168 							conn->hdrdgst_en,
2169 							conn->datadgst_en, 0);
2170 		break;
2171 	case ISCSI_PARAM_DATADGST_EN:
2172 		err = iscsi_set_param(cls_conn, param, buf, buflen);
2173 		if (!err && conn->datadgst_en)
2174 			err = csk->cdev->csk_ddp_setup_digest(csk, csk->tid,
2175 							conn->hdrdgst_en,
2176 							conn->datadgst_en, 0);
2177 		break;
2178 	case ISCSI_PARAM_MAX_R2T:
2179 		return iscsi_tcp_set_max_r2t(conn, buf);
2180 	case ISCSI_PARAM_MAX_RECV_DLENGTH:
2181 		err = iscsi_set_param(cls_conn, param, buf, buflen);
2182 		if (!err)
2183 			err = cxgbi_conn_max_recv_dlength(conn);
2184 		break;
2185 	case ISCSI_PARAM_MAX_XMIT_DLENGTH:
2186 		err = iscsi_set_param(cls_conn, param, buf, buflen);
2187 		if (!err)
2188 			err = cxgbi_conn_max_xmit_dlength(conn);
2189 		break;
2190 	default:
2191 		return iscsi_set_param(cls_conn, param, buf, buflen);
2192 	}
2193 	return err;
2194 }
2195 EXPORT_SYMBOL_GPL(cxgbi_set_conn_param);
2196 
2197 int cxgbi_get_ep_param(struct iscsi_endpoint *ep, enum iscsi_param param,
2198 		       char *buf)
2199 {
2200 	struct cxgbi_endpoint *cep = ep->dd_data;
2201 	struct cxgbi_sock *csk;
2202 	int len;
2203 
2204 	log_debug(1 << CXGBI_DBG_ISCSI,
2205 		"cls_conn 0x%p, param %d.\n", ep, param);
2206 
2207 	switch (param) {
2208 	case ISCSI_PARAM_CONN_PORT:
2209 	case ISCSI_PARAM_CONN_ADDRESS:
2210 		if (!cep)
2211 			return -ENOTCONN;
2212 
2213 		csk = cep->csk;
2214 		if (!csk)
2215 			return -ENOTCONN;
2216 
2217 		return iscsi_conn_get_addr_param((struct sockaddr_storage *)
2218 						 &csk->daddr, param, buf);
2219 	default:
2220 		return -ENOSYS;
2221 	}
2222 	return len;
2223 }
2224 EXPORT_SYMBOL_GPL(cxgbi_get_ep_param);
2225 
2226 struct iscsi_cls_conn *
2227 cxgbi_create_conn(struct iscsi_cls_session *cls_session, u32 cid)
2228 {
2229 	struct iscsi_cls_conn *cls_conn;
2230 	struct iscsi_conn *conn;
2231 	struct iscsi_tcp_conn *tcp_conn;
2232 	struct cxgbi_conn *cconn;
2233 
2234 	cls_conn = iscsi_tcp_conn_setup(cls_session, sizeof(*cconn), cid);
2235 	if (!cls_conn)
2236 		return NULL;
2237 
2238 	conn = cls_conn->dd_data;
2239 	tcp_conn = conn->dd_data;
2240 	cconn = tcp_conn->dd_data;
2241 	cconn->iconn = conn;
2242 
2243 	log_debug(1 << CXGBI_DBG_ISCSI,
2244 		"cid %u(0x%x), cls 0x%p,0x%p, conn 0x%p,0x%p,0x%p.\n",
2245 		cid, cid, cls_session, cls_conn, conn, tcp_conn, cconn);
2246 
2247 	return cls_conn;
2248 }
2249 EXPORT_SYMBOL_GPL(cxgbi_create_conn);
2250 
2251 int cxgbi_bind_conn(struct iscsi_cls_session *cls_session,
2252 				struct iscsi_cls_conn *cls_conn,
2253 				u64 transport_eph, int is_leading)
2254 {
2255 	struct iscsi_conn *conn = cls_conn->dd_data;
2256 	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
2257 	struct cxgbi_conn *cconn = tcp_conn->dd_data;
2258 	struct iscsi_endpoint *ep;
2259 	struct cxgbi_endpoint *cep;
2260 	struct cxgbi_sock *csk;
2261 	int err;
2262 
2263 	ep = iscsi_lookup_endpoint(transport_eph);
2264 	if (!ep)
2265 		return -EINVAL;
2266 
2267 	/*  setup ddp pagesize */
2268 	cep = ep->dd_data;
2269 	csk = cep->csk;
2270 	err = csk->cdev->csk_ddp_setup_pgidx(csk, csk->tid, page_idx, 0);
2271 	if (err < 0)
2272 		return err;
2273 
2274 	err = iscsi_conn_bind(cls_session, cls_conn, is_leading);
2275 	if (err)
2276 		return -EINVAL;
2277 
2278 	/*  calculate the tag idx bits needed for this conn based on cmds_max */
2279 	cconn->task_idx_bits = (__ilog2_u32(conn->session->cmds_max - 1)) + 1;
2280 
2281 	write_lock_bh(&csk->callback_lock);
2282 	csk->user_data = conn;
2283 	cconn->chba = cep->chba;
2284 	cconn->cep = cep;
2285 	cep->cconn = cconn;
2286 	write_unlock_bh(&csk->callback_lock);
2287 
2288 	cxgbi_conn_max_xmit_dlength(conn);
2289 	cxgbi_conn_max_recv_dlength(conn);
2290 
2291 	log_debug(1 << CXGBI_DBG_ISCSI,
2292 		"cls 0x%p,0x%p, ep 0x%p, cconn 0x%p, csk 0x%p.\n",
2293 		cls_session, cls_conn, ep, cconn, csk);
2294 	/*  init recv engine */
2295 	iscsi_tcp_hdr_recv_prep(tcp_conn);
2296 
2297 	return 0;
2298 }
2299 EXPORT_SYMBOL_GPL(cxgbi_bind_conn);
2300 
2301 struct iscsi_cls_session *cxgbi_create_session(struct iscsi_endpoint *ep,
2302 						u16 cmds_max, u16 qdepth,
2303 						u32 initial_cmdsn)
2304 {
2305 	struct cxgbi_endpoint *cep;
2306 	struct cxgbi_hba *chba;
2307 	struct Scsi_Host *shost;
2308 	struct iscsi_cls_session *cls_session;
2309 	struct iscsi_session *session;
2310 
2311 	if (!ep) {
2312 		pr_err("missing endpoint.\n");
2313 		return NULL;
2314 	}
2315 
2316 	cep = ep->dd_data;
2317 	chba = cep->chba;
2318 	shost = chba->shost;
2319 
2320 	BUG_ON(chba != iscsi_host_priv(shost));
2321 
2322 	cls_session = iscsi_session_setup(chba->cdev->itp, shost,
2323 					cmds_max, 0,
2324 					sizeof(struct iscsi_tcp_task) +
2325 					sizeof(struct cxgbi_task_data),
2326 					initial_cmdsn, ISCSI_MAX_TARGET);
2327 	if (!cls_session)
2328 		return NULL;
2329 
2330 	session = cls_session->dd_data;
2331 	if (iscsi_tcp_r2tpool_alloc(session))
2332 		goto remove_session;
2333 
2334 	log_debug(1 << CXGBI_DBG_ISCSI,
2335 		"ep 0x%p, cls sess 0x%p.\n", ep, cls_session);
2336 	return cls_session;
2337 
2338 remove_session:
2339 	iscsi_session_teardown(cls_session);
2340 	return NULL;
2341 }
2342 EXPORT_SYMBOL_GPL(cxgbi_create_session);
2343 
2344 void cxgbi_destroy_session(struct iscsi_cls_session *cls_session)
2345 {
2346 	log_debug(1 << CXGBI_DBG_ISCSI,
2347 		"cls sess 0x%p.\n", cls_session);
2348 
2349 	iscsi_tcp_r2tpool_free(cls_session->dd_data);
2350 	iscsi_session_teardown(cls_session);
2351 }
2352 EXPORT_SYMBOL_GPL(cxgbi_destroy_session);
2353 
2354 int cxgbi_set_host_param(struct Scsi_Host *shost, enum iscsi_host_param param,
2355 			char *buf, int buflen)
2356 {
2357 	struct cxgbi_hba *chba = iscsi_host_priv(shost);
2358 
2359 	if (!chba->ndev) {
2360 		shost_printk(KERN_ERR, shost, "Could not get host param. "
2361 				"netdev for host not set.\n");
2362 		return -ENODEV;
2363 	}
2364 
2365 	log_debug(1 << CXGBI_DBG_ISCSI,
2366 		"shost 0x%p, hba 0x%p,%s, param %d, buf(%d) %s.\n",
2367 		shost, chba, chba->ndev->name, param, buflen, buf);
2368 
2369 	switch (param) {
2370 	case ISCSI_HOST_PARAM_IPADDRESS:
2371 	{
2372 		__be32 addr = in_aton(buf);
2373 		log_debug(1 << CXGBI_DBG_ISCSI,
2374 			"hba %s, req. ipv4 %pI4.\n", chba->ndev->name, &addr);
2375 		cxgbi_set_iscsi_ipv4(chba, addr);
2376 		return 0;
2377 	}
2378 	case ISCSI_HOST_PARAM_HWADDRESS:
2379 	case ISCSI_HOST_PARAM_NETDEV_NAME:
2380 		return 0;
2381 	default:
2382 		return iscsi_host_set_param(shost, param, buf, buflen);
2383 	}
2384 }
2385 EXPORT_SYMBOL_GPL(cxgbi_set_host_param);
2386 
2387 int cxgbi_get_host_param(struct Scsi_Host *shost, enum iscsi_host_param param,
2388 			char *buf)
2389 {
2390 	struct cxgbi_hba *chba = iscsi_host_priv(shost);
2391 	int len = 0;
2392 
2393 	if (!chba->ndev) {
2394 		shost_printk(KERN_ERR, shost, "Could not get host param. "
2395 				"netdev for host not set.\n");
2396 		return -ENODEV;
2397 	}
2398 
2399 	log_debug(1 << CXGBI_DBG_ISCSI,
2400 		"shost 0x%p, hba 0x%p,%s, param %d.\n",
2401 		shost, chba, chba->ndev->name, param);
2402 
2403 	switch (param) {
2404 	case ISCSI_HOST_PARAM_HWADDRESS:
2405 		len = sysfs_format_mac(buf, chba->ndev->dev_addr, 6);
2406 		break;
2407 	case ISCSI_HOST_PARAM_NETDEV_NAME:
2408 		len = sprintf(buf, "%s\n", chba->ndev->name);
2409 		break;
2410 	case ISCSI_HOST_PARAM_IPADDRESS:
2411 	{
2412 		__be32 addr;
2413 
2414 		addr = cxgbi_get_iscsi_ipv4(chba);
2415 		len = sprintf(buf, "%pI4", &addr);
2416 		log_debug(1 << CXGBI_DBG_ISCSI,
2417 			"hba %s, ipv4 %pI4.\n", chba->ndev->name, &addr);
2418 		break;
2419 	}
2420 	default:
2421 		return iscsi_host_get_param(shost, param, buf);
2422 	}
2423 
2424 	return len;
2425 }
2426 EXPORT_SYMBOL_GPL(cxgbi_get_host_param);
2427 
2428 struct iscsi_endpoint *cxgbi_ep_connect(struct Scsi_Host *shost,
2429 					struct sockaddr *dst_addr,
2430 					int non_blocking)
2431 {
2432 	struct iscsi_endpoint *ep;
2433 	struct cxgbi_endpoint *cep;
2434 	struct cxgbi_hba *hba = NULL;
2435 	struct cxgbi_sock *csk;
2436 	int err = -EINVAL;
2437 
2438 	log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_SOCK,
2439 		"shost 0x%p, non_blocking %d, dst_addr 0x%p.\n",
2440 		shost, non_blocking, dst_addr);
2441 
2442 	if (shost) {
2443 		hba = iscsi_host_priv(shost);
2444 		if (!hba) {
2445 			pr_info("shost 0x%p, priv NULL.\n", shost);
2446 			goto err_out;
2447 		}
2448 	}
2449 
2450 	csk = cxgbi_check_route(dst_addr);
2451 	if (IS_ERR(csk))
2452 		return (struct iscsi_endpoint *)csk;
2453 	cxgbi_sock_get(csk);
2454 
2455 	if (!hba)
2456 		hba = csk->cdev->hbas[csk->port_id];
2457 	else if (hba != csk->cdev->hbas[csk->port_id]) {
2458 		pr_info("Could not connect through requested host %u"
2459 			"hba 0x%p != 0x%p (%u).\n",
2460 			shost->host_no, hba,
2461 			csk->cdev->hbas[csk->port_id], csk->port_id);
2462 		err = -ENOSPC;
2463 		goto release_conn;
2464 	}
2465 
2466 	err = sock_get_port(csk);
2467 	if (err)
2468 		goto release_conn;
2469 
2470 	cxgbi_sock_set_state(csk, CTP_CONNECTING);
2471 	err = csk->cdev->csk_init_act_open(csk);
2472 	if (err)
2473 		goto release_conn;
2474 
2475 	if (cxgbi_sock_is_closing(csk)) {
2476 		err = -ENOSPC;
2477 		pr_info("csk 0x%p is closing.\n", csk);
2478 		goto release_conn;
2479 	}
2480 
2481 	ep = iscsi_create_endpoint(sizeof(*cep));
2482 	if (!ep) {
2483 		err = -ENOMEM;
2484 		pr_info("iscsi alloc ep, OOM.\n");
2485 		goto release_conn;
2486 	}
2487 
2488 	cep = ep->dd_data;
2489 	cep->csk = csk;
2490 	cep->chba = hba;
2491 
2492 	log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_SOCK,
2493 		"ep 0x%p, cep 0x%p, csk 0x%p, hba 0x%p,%s.\n",
2494 		ep, cep, csk, hba, hba->ndev->name);
2495 	return ep;
2496 
2497 release_conn:
2498 	cxgbi_sock_put(csk);
2499 	cxgbi_sock_closed(csk);
2500 err_out:
2501 	return ERR_PTR(err);
2502 }
2503 EXPORT_SYMBOL_GPL(cxgbi_ep_connect);
2504 
2505 int cxgbi_ep_poll(struct iscsi_endpoint *ep, int timeout_ms)
2506 {
2507 	struct cxgbi_endpoint *cep = ep->dd_data;
2508 	struct cxgbi_sock *csk = cep->csk;
2509 
2510 	if (!cxgbi_sock_is_established(csk))
2511 		return 0;
2512 	return 1;
2513 }
2514 EXPORT_SYMBOL_GPL(cxgbi_ep_poll);
2515 
2516 void cxgbi_ep_disconnect(struct iscsi_endpoint *ep)
2517 {
2518 	struct cxgbi_endpoint *cep = ep->dd_data;
2519 	struct cxgbi_conn *cconn = cep->cconn;
2520 	struct cxgbi_sock *csk = cep->csk;
2521 
2522 	log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_SOCK,
2523 		"ep 0x%p, cep 0x%p, cconn 0x%p, csk 0x%p,%u,0x%lx.\n",
2524 		ep, cep, cconn, csk, csk->state, csk->flags);
2525 
2526 	if (cconn && cconn->iconn) {
2527 		iscsi_suspend_tx(cconn->iconn);
2528 		write_lock_bh(&csk->callback_lock);
2529 		cep->csk->user_data = NULL;
2530 		cconn->cep = NULL;
2531 		write_unlock_bh(&csk->callback_lock);
2532 	}
2533 	iscsi_destroy_endpoint(ep);
2534 
2535 	if (likely(csk->state >= CTP_ESTABLISHED))
2536 		need_active_close(csk);
2537 	else
2538 		cxgbi_sock_closed(csk);
2539 
2540 	cxgbi_sock_put(csk);
2541 }
2542 EXPORT_SYMBOL_GPL(cxgbi_ep_disconnect);
2543 
2544 int cxgbi_iscsi_init(struct iscsi_transport *itp,
2545 			struct scsi_transport_template **stt)
2546 {
2547 	*stt = iscsi_register_transport(itp);
2548 	if (*stt == NULL) {
2549 		pr_err("unable to register %s transport 0x%p.\n",
2550 			itp->name, itp);
2551 		return -ENODEV;
2552 	}
2553 	log_debug(1 << CXGBI_DBG_ISCSI,
2554 		"%s, registered iscsi transport 0x%p.\n",
2555 		itp->name, stt);
2556 	return 0;
2557 }
2558 EXPORT_SYMBOL_GPL(cxgbi_iscsi_init);
2559 
2560 void cxgbi_iscsi_cleanup(struct iscsi_transport *itp,
2561 			struct scsi_transport_template **stt)
2562 {
2563 	if (*stt) {
2564 		log_debug(1 << CXGBI_DBG_ISCSI,
2565 			"de-register transport 0x%p, %s, stt 0x%p.\n",
2566 			itp, itp->name, *stt);
2567 		*stt = NULL;
2568 		iscsi_unregister_transport(itp);
2569 	}
2570 }
2571 EXPORT_SYMBOL_GPL(cxgbi_iscsi_cleanup);
2572 
2573 umode_t cxgbi_attr_is_visible(int param_type, int param)
2574 {
2575 	switch (param_type) {
2576 	case ISCSI_HOST_PARAM:
2577 		switch (param) {
2578 		case ISCSI_HOST_PARAM_NETDEV_NAME:
2579 		case ISCSI_HOST_PARAM_HWADDRESS:
2580 		case ISCSI_HOST_PARAM_IPADDRESS:
2581 		case ISCSI_HOST_PARAM_INITIATOR_NAME:
2582 			return S_IRUGO;
2583 		default:
2584 			return 0;
2585 		}
2586 	case ISCSI_PARAM:
2587 		switch (param) {
2588 		case ISCSI_PARAM_MAX_RECV_DLENGTH:
2589 		case ISCSI_PARAM_MAX_XMIT_DLENGTH:
2590 		case ISCSI_PARAM_HDRDGST_EN:
2591 		case ISCSI_PARAM_DATADGST_EN:
2592 		case ISCSI_PARAM_CONN_ADDRESS:
2593 		case ISCSI_PARAM_CONN_PORT:
2594 		case ISCSI_PARAM_EXP_STATSN:
2595 		case ISCSI_PARAM_PERSISTENT_ADDRESS:
2596 		case ISCSI_PARAM_PERSISTENT_PORT:
2597 		case ISCSI_PARAM_PING_TMO:
2598 		case ISCSI_PARAM_RECV_TMO:
2599 		case ISCSI_PARAM_INITIAL_R2T_EN:
2600 		case ISCSI_PARAM_MAX_R2T:
2601 		case ISCSI_PARAM_IMM_DATA_EN:
2602 		case ISCSI_PARAM_FIRST_BURST:
2603 		case ISCSI_PARAM_MAX_BURST:
2604 		case ISCSI_PARAM_PDU_INORDER_EN:
2605 		case ISCSI_PARAM_DATASEQ_INORDER_EN:
2606 		case ISCSI_PARAM_ERL:
2607 		case ISCSI_PARAM_TARGET_NAME:
2608 		case ISCSI_PARAM_TPGT:
2609 		case ISCSI_PARAM_USERNAME:
2610 		case ISCSI_PARAM_PASSWORD:
2611 		case ISCSI_PARAM_USERNAME_IN:
2612 		case ISCSI_PARAM_PASSWORD_IN:
2613 		case ISCSI_PARAM_FAST_ABORT:
2614 		case ISCSI_PARAM_ABORT_TMO:
2615 		case ISCSI_PARAM_LU_RESET_TMO:
2616 		case ISCSI_PARAM_TGT_RESET_TMO:
2617 		case ISCSI_PARAM_IFACE_NAME:
2618 		case ISCSI_PARAM_INITIATOR_NAME:
2619 			return S_IRUGO;
2620 		default:
2621 			return 0;
2622 		}
2623 	}
2624 
2625 	return 0;
2626 }
2627 EXPORT_SYMBOL_GPL(cxgbi_attr_is_visible);
2628 
2629 static int __init libcxgbi_init_module(void)
2630 {
2631 	sw_tag_idx_bits = (__ilog2_u32(ISCSI_ITT_MASK)) + 1;
2632 	sw_tag_age_bits = (__ilog2_u32(ISCSI_AGE_MASK)) + 1;
2633 
2634 	pr_info("tag itt 0x%x, %u bits, age 0x%x, %u bits.\n",
2635 		ISCSI_ITT_MASK, sw_tag_idx_bits,
2636 		ISCSI_AGE_MASK, sw_tag_age_bits);
2637 
2638 	ddp_setup_host_page_size();
2639 	return 0;
2640 }
2641 
2642 static void __exit libcxgbi_exit_module(void)
2643 {
2644 	cxgbi_device_unregister_all(0xFF);
2645 	return;
2646 }
2647 
2648 module_init(libcxgbi_init_module);
2649 module_exit(libcxgbi_exit_module);
2650