xref: /openbmc/linux/drivers/target/sbp/sbp_target.c (revision 3ca3af7d)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * SBP2 target driver (SCSI over IEEE1394 in target mode)
4  *
5  * Copyright (C) 2011  Chris Boot <bootc@bootc.net>
6  */
7 
8 #define KMSG_COMPONENT "sbp_target"
9 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
10 
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/init.h>
14 #include <linux/types.h>
15 #include <linux/string.h>
16 #include <linux/configfs.h>
17 #include <linux/ctype.h>
18 #include <linux/delay.h>
19 #include <linux/firewire.h>
20 #include <linux/firewire-constants.h>
21 #include <scsi/scsi_proto.h>
22 #include <scsi/scsi_tcq.h>
23 #include <target/target_core_base.h>
24 #include <target/target_core_backend.h>
25 #include <target/target_core_fabric.h>
26 #include <asm/unaligned.h>
27 
28 #include "sbp_target.h"
29 
30 /* FireWire address region for management and command block address handlers */
31 static const struct fw_address_region sbp_register_region = {
32 	.start	= CSR_REGISTER_BASE + 0x10000,
33 	.end	= 0x1000000000000ULL,
34 };
35 
36 static const u32 sbp_unit_directory_template[] = {
37 	0x1200609e, /* unit_specifier_id: NCITS/T10 */
38 	0x13010483, /* unit_sw_version: 1155D Rev 4 */
39 	0x3800609e, /* command_set_specifier_id: NCITS/T10 */
40 	0x390104d8, /* command_set: SPC-2 */
41 	0x3b000000, /* command_set_revision: 0 */
42 	0x3c000001, /* firmware_revision: 1 */
43 };
44 
45 #define SESSION_MAINTENANCE_INTERVAL HZ
46 
47 static atomic_t login_id = ATOMIC_INIT(0);
48 
49 static void session_maintenance_work(struct work_struct *);
50 static int sbp_run_transaction(struct fw_card *, int, int, int, int,
51 		unsigned long long, void *, size_t);
52 
53 static int read_peer_guid(u64 *guid, const struct sbp_management_request *req)
54 {
55 	int ret;
56 	__be32 high, low;
57 
58 	ret = sbp_run_transaction(req->card, TCODE_READ_QUADLET_REQUEST,
59 			req->node_addr, req->generation, req->speed,
60 			(CSR_REGISTER_BASE | CSR_CONFIG_ROM) + 3 * 4,
61 			&high, sizeof(high));
62 	if (ret != RCODE_COMPLETE)
63 		return ret;
64 
65 	ret = sbp_run_transaction(req->card, TCODE_READ_QUADLET_REQUEST,
66 			req->node_addr, req->generation, req->speed,
67 			(CSR_REGISTER_BASE | CSR_CONFIG_ROM) + 4 * 4,
68 			&low, sizeof(low));
69 	if (ret != RCODE_COMPLETE)
70 		return ret;
71 
72 	*guid = (u64)be32_to_cpu(high) << 32 | be32_to_cpu(low);
73 
74 	return RCODE_COMPLETE;
75 }
76 
77 static struct sbp_session *sbp_session_find_by_guid(
78 	struct sbp_tpg *tpg, u64 guid)
79 {
80 	struct se_session *se_sess;
81 	struct sbp_session *sess, *found = NULL;
82 
83 	spin_lock_bh(&tpg->se_tpg.session_lock);
84 	list_for_each_entry(se_sess, &tpg->se_tpg.tpg_sess_list, sess_list) {
85 		sess = se_sess->fabric_sess_ptr;
86 		if (sess->guid == guid)
87 			found = sess;
88 	}
89 	spin_unlock_bh(&tpg->se_tpg.session_lock);
90 
91 	return found;
92 }
93 
94 static struct sbp_login_descriptor *sbp_login_find_by_lun(
95 		struct sbp_session *session, u32 unpacked_lun)
96 {
97 	struct sbp_login_descriptor *login, *found = NULL;
98 
99 	spin_lock_bh(&session->lock);
100 	list_for_each_entry(login, &session->login_list, link) {
101 		if (login->login_lun == unpacked_lun)
102 			found = login;
103 	}
104 	spin_unlock_bh(&session->lock);
105 
106 	return found;
107 }
108 
109 static int sbp_login_count_all_by_lun(
110 		struct sbp_tpg *tpg,
111 		u32 unpacked_lun,
112 		int exclusive)
113 {
114 	struct se_session *se_sess;
115 	struct sbp_session *sess;
116 	struct sbp_login_descriptor *login;
117 	int count = 0;
118 
119 	spin_lock_bh(&tpg->se_tpg.session_lock);
120 	list_for_each_entry(se_sess, &tpg->se_tpg.tpg_sess_list, sess_list) {
121 		sess = se_sess->fabric_sess_ptr;
122 
123 		spin_lock_bh(&sess->lock);
124 		list_for_each_entry(login, &sess->login_list, link) {
125 			if (login->login_lun != unpacked_lun)
126 				continue;
127 
128 			if (!exclusive || login->exclusive)
129 				count++;
130 		}
131 		spin_unlock_bh(&sess->lock);
132 	}
133 	spin_unlock_bh(&tpg->se_tpg.session_lock);
134 
135 	return count;
136 }
137 
138 static struct sbp_login_descriptor *sbp_login_find_by_id(
139 	struct sbp_tpg *tpg, int login_id)
140 {
141 	struct se_session *se_sess;
142 	struct sbp_session *sess;
143 	struct sbp_login_descriptor *login, *found = NULL;
144 
145 	spin_lock_bh(&tpg->se_tpg.session_lock);
146 	list_for_each_entry(se_sess, &tpg->se_tpg.tpg_sess_list, sess_list) {
147 		sess = se_sess->fabric_sess_ptr;
148 
149 		spin_lock_bh(&sess->lock);
150 		list_for_each_entry(login, &sess->login_list, link) {
151 			if (login->login_id == login_id)
152 				found = login;
153 		}
154 		spin_unlock_bh(&sess->lock);
155 	}
156 	spin_unlock_bh(&tpg->se_tpg.session_lock);
157 
158 	return found;
159 }
160 
161 static u32 sbp_get_lun_from_tpg(struct sbp_tpg *tpg, u32 login_lun, int *err)
162 {
163 	struct se_portal_group *se_tpg = &tpg->se_tpg;
164 	struct se_lun *se_lun;
165 
166 	rcu_read_lock();
167 	hlist_for_each_entry_rcu(se_lun, &se_tpg->tpg_lun_hlist, link) {
168 		if (se_lun->unpacked_lun == login_lun) {
169 			rcu_read_unlock();
170 			*err = 0;
171 			return login_lun;
172 		}
173 	}
174 	rcu_read_unlock();
175 
176 	*err = -ENODEV;
177 	return login_lun;
178 }
179 
180 static struct sbp_session *sbp_session_create(
181 		struct sbp_tpg *tpg,
182 		u64 guid)
183 {
184 	struct sbp_session *sess;
185 	int ret;
186 	char guid_str[17];
187 
188 	snprintf(guid_str, sizeof(guid_str), "%016llx", guid);
189 
190 	sess = kmalloc(sizeof(*sess), GFP_KERNEL);
191 	if (!sess)
192 		return ERR_PTR(-ENOMEM);
193 
194 	spin_lock_init(&sess->lock);
195 	INIT_LIST_HEAD(&sess->login_list);
196 	INIT_DELAYED_WORK(&sess->maint_work, session_maintenance_work);
197 	sess->guid = guid;
198 
199 	sess->se_sess = target_setup_session(&tpg->se_tpg, 128,
200 					     sizeof(struct sbp_target_request),
201 					     TARGET_PROT_NORMAL, guid_str,
202 					     sess, NULL);
203 	if (IS_ERR(sess->se_sess)) {
204 		pr_err("failed to init se_session\n");
205 		ret = PTR_ERR(sess->se_sess);
206 		kfree(sess);
207 		return ERR_PTR(ret);
208 	}
209 
210 	return sess;
211 }
212 
213 static void sbp_session_release(struct sbp_session *sess, bool cancel_work)
214 {
215 	spin_lock_bh(&sess->lock);
216 	if (!list_empty(&sess->login_list)) {
217 		spin_unlock_bh(&sess->lock);
218 		return;
219 	}
220 	spin_unlock_bh(&sess->lock);
221 
222 	if (cancel_work)
223 		cancel_delayed_work_sync(&sess->maint_work);
224 
225 	target_remove_session(sess->se_sess);
226 
227 	if (sess->card)
228 		fw_card_put(sess->card);
229 
230 	kfree(sess);
231 }
232 
233 static void sbp_target_agent_unregister(struct sbp_target_agent *);
234 
235 static void sbp_login_release(struct sbp_login_descriptor *login,
236 	bool cancel_work)
237 {
238 	struct sbp_session *sess = login->sess;
239 
240 	/* FIXME: abort/wait on tasks */
241 
242 	sbp_target_agent_unregister(login->tgt_agt);
243 
244 	if (sess) {
245 		spin_lock_bh(&sess->lock);
246 		list_del(&login->link);
247 		spin_unlock_bh(&sess->lock);
248 
249 		sbp_session_release(sess, cancel_work);
250 	}
251 
252 	kfree(login);
253 }
254 
255 static struct sbp_target_agent *sbp_target_agent_register(
256 	struct sbp_login_descriptor *);
257 
258 static void sbp_management_request_login(
259 	struct sbp_management_agent *agent, struct sbp_management_request *req,
260 	int *status_data_size)
261 {
262 	struct sbp_tport *tport = agent->tport;
263 	struct sbp_tpg *tpg = tport->tpg;
264 	struct sbp_session *sess;
265 	struct sbp_login_descriptor *login;
266 	struct sbp_login_response_block *response;
267 	u64 guid;
268 	u32 unpacked_lun;
269 	int login_response_len, ret;
270 
271 	unpacked_lun = sbp_get_lun_from_tpg(tpg,
272 			LOGIN_ORB_LUN(be32_to_cpu(req->orb.misc)), &ret);
273 	if (ret) {
274 		pr_notice("login to unknown LUN: %d\n",
275 			LOGIN_ORB_LUN(be32_to_cpu(req->orb.misc)));
276 
277 		req->status.status = cpu_to_be32(
278 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
279 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_LUN_NOTSUPP));
280 		return;
281 	}
282 
283 	ret = read_peer_guid(&guid, req);
284 	if (ret != RCODE_COMPLETE) {
285 		pr_warn("failed to read peer GUID: %d\n", ret);
286 
287 		req->status.status = cpu_to_be32(
288 			STATUS_BLOCK_RESP(STATUS_RESP_TRANSPORT_FAILURE) |
289 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_UNSPECIFIED_ERROR));
290 		return;
291 	}
292 
293 	pr_notice("mgt_agent LOGIN to LUN %d from %016llx\n",
294 		unpacked_lun, guid);
295 
296 	sess = sbp_session_find_by_guid(tpg, guid);
297 	if (sess) {
298 		login = sbp_login_find_by_lun(sess, unpacked_lun);
299 		if (login) {
300 			pr_notice("initiator already logged-in\n");
301 
302 			/*
303 			 * SBP-2 R4 says we should return access denied, but
304 			 * that can confuse initiators. Instead we need to
305 			 * treat this like a reconnect, but send the login
306 			 * response block like a fresh login.
307 			 *
308 			 * This is required particularly in the case of Apple
309 			 * devices booting off the FireWire target, where
310 			 * the firmware has an active login to the target. When
311 			 * the OS takes control of the session it issues its own
312 			 * LOGIN rather than a RECONNECT. To avoid the machine
313 			 * waiting until the reconnect_hold expires, we can skip
314 			 * the ACCESS_DENIED errors to speed things up.
315 			 */
316 
317 			goto already_logged_in;
318 		}
319 	}
320 
321 	/*
322 	 * check exclusive bit in login request
323 	 * reject with access_denied if any logins present
324 	 */
325 	if (LOGIN_ORB_EXCLUSIVE(be32_to_cpu(req->orb.misc)) &&
326 			sbp_login_count_all_by_lun(tpg, unpacked_lun, 0)) {
327 		pr_warn("refusing exclusive login with other active logins\n");
328 
329 		req->status.status = cpu_to_be32(
330 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
331 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_ACCESS_DENIED));
332 		return;
333 	}
334 
335 	/*
336 	 * check exclusive bit in any existing login descriptor
337 	 * reject with access_denied if any exclusive logins present
338 	 */
339 	if (sbp_login_count_all_by_lun(tpg, unpacked_lun, 1)) {
340 		pr_warn("refusing login while another exclusive login present\n");
341 
342 		req->status.status = cpu_to_be32(
343 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
344 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_ACCESS_DENIED));
345 		return;
346 	}
347 
348 	/*
349 	 * check we haven't exceeded the number of allowed logins
350 	 * reject with resources_unavailable if we have
351 	 */
352 	if (sbp_login_count_all_by_lun(tpg, unpacked_lun, 0) >=
353 			tport->max_logins_per_lun) {
354 		pr_warn("max number of logins reached\n");
355 
356 		req->status.status = cpu_to_be32(
357 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
358 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_RESOURCES_UNAVAIL));
359 		return;
360 	}
361 
362 	if (!sess) {
363 		sess = sbp_session_create(tpg, guid);
364 		if (IS_ERR(sess)) {
365 			switch (PTR_ERR(sess)) {
366 			case -EPERM:
367 				ret = SBP_STATUS_ACCESS_DENIED;
368 				break;
369 			default:
370 				ret = SBP_STATUS_RESOURCES_UNAVAIL;
371 				break;
372 			}
373 
374 			req->status.status = cpu_to_be32(
375 				STATUS_BLOCK_RESP(
376 					STATUS_RESP_REQUEST_COMPLETE) |
377 				STATUS_BLOCK_SBP_STATUS(ret));
378 			return;
379 		}
380 
381 		sess->node_id = req->node_addr;
382 		sess->card = fw_card_get(req->card);
383 		sess->generation = req->generation;
384 		sess->speed = req->speed;
385 
386 		schedule_delayed_work(&sess->maint_work,
387 				SESSION_MAINTENANCE_INTERVAL);
388 	}
389 
390 	/* only take the latest reconnect_hold into account */
391 	sess->reconnect_hold = min(
392 		1 << LOGIN_ORB_RECONNECT(be32_to_cpu(req->orb.misc)),
393 		tport->max_reconnect_timeout) - 1;
394 
395 	login = kmalloc(sizeof(*login), GFP_KERNEL);
396 	if (!login) {
397 		pr_err("failed to allocate login descriptor\n");
398 
399 		sbp_session_release(sess, true);
400 
401 		req->status.status = cpu_to_be32(
402 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
403 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_RESOURCES_UNAVAIL));
404 		return;
405 	}
406 
407 	login->sess = sess;
408 	login->login_lun = unpacked_lun;
409 	login->status_fifo_addr = sbp2_pointer_to_addr(&req->orb.status_fifo);
410 	login->exclusive = LOGIN_ORB_EXCLUSIVE(be32_to_cpu(req->orb.misc));
411 	login->login_id = atomic_inc_return(&login_id);
412 
413 	login->tgt_agt = sbp_target_agent_register(login);
414 	if (IS_ERR(login->tgt_agt)) {
415 		ret = PTR_ERR(login->tgt_agt);
416 		pr_err("failed to map command block handler: %d\n", ret);
417 
418 		sbp_session_release(sess, true);
419 		kfree(login);
420 
421 		req->status.status = cpu_to_be32(
422 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
423 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_RESOURCES_UNAVAIL));
424 		return;
425 	}
426 
427 	spin_lock_bh(&sess->lock);
428 	list_add_tail(&login->link, &sess->login_list);
429 	spin_unlock_bh(&sess->lock);
430 
431 already_logged_in:
432 	response = kzalloc(sizeof(*response), GFP_KERNEL);
433 	if (!response) {
434 		pr_err("failed to allocate login response block\n");
435 
436 		sbp_login_release(login, true);
437 
438 		req->status.status = cpu_to_be32(
439 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
440 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_RESOURCES_UNAVAIL));
441 		return;
442 	}
443 
444 	login_response_len = clamp_val(
445 			LOGIN_ORB_RESPONSE_LENGTH(be32_to_cpu(req->orb.length)),
446 			12, sizeof(*response));
447 	response->misc = cpu_to_be32(
448 		((login_response_len & 0xffff) << 16) |
449 		(login->login_id & 0xffff));
450 	response->reconnect_hold = cpu_to_be32(sess->reconnect_hold & 0xffff);
451 	addr_to_sbp2_pointer(login->tgt_agt->handler.offset,
452 		&response->command_block_agent);
453 
454 	ret = sbp_run_transaction(sess->card, TCODE_WRITE_BLOCK_REQUEST,
455 		sess->node_id, sess->generation, sess->speed,
456 		sbp2_pointer_to_addr(&req->orb.ptr2), response,
457 		login_response_len);
458 	if (ret != RCODE_COMPLETE) {
459 		pr_debug("failed to write login response block: %x\n", ret);
460 
461 		kfree(response);
462 		sbp_login_release(login, true);
463 
464 		req->status.status = cpu_to_be32(
465 			STATUS_BLOCK_RESP(STATUS_RESP_TRANSPORT_FAILURE) |
466 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_UNSPECIFIED_ERROR));
467 		return;
468 	}
469 
470 	kfree(response);
471 
472 	req->status.status = cpu_to_be32(
473 		STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
474 		STATUS_BLOCK_SBP_STATUS(SBP_STATUS_OK));
475 }
476 
477 static void sbp_management_request_query_logins(
478 	struct sbp_management_agent *agent, struct sbp_management_request *req,
479 	int *status_data_size)
480 {
481 	pr_notice("QUERY LOGINS not implemented\n");
482 	/* FIXME: implement */
483 
484 	req->status.status = cpu_to_be32(
485 		STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
486 		STATUS_BLOCK_SBP_STATUS(SBP_STATUS_REQ_TYPE_NOTSUPP));
487 }
488 
489 static void sbp_management_request_reconnect(
490 	struct sbp_management_agent *agent, struct sbp_management_request *req,
491 	int *status_data_size)
492 {
493 	struct sbp_tport *tport = agent->tport;
494 	struct sbp_tpg *tpg = tport->tpg;
495 	int ret;
496 	u64 guid;
497 	struct sbp_login_descriptor *login;
498 
499 	ret = read_peer_guid(&guid, req);
500 	if (ret != RCODE_COMPLETE) {
501 		pr_warn("failed to read peer GUID: %d\n", ret);
502 
503 		req->status.status = cpu_to_be32(
504 			STATUS_BLOCK_RESP(STATUS_RESP_TRANSPORT_FAILURE) |
505 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_UNSPECIFIED_ERROR));
506 		return;
507 	}
508 
509 	pr_notice("mgt_agent RECONNECT from %016llx\n", guid);
510 
511 	login = sbp_login_find_by_id(tpg,
512 		RECONNECT_ORB_LOGIN_ID(be32_to_cpu(req->orb.misc)));
513 
514 	if (!login) {
515 		pr_err("mgt_agent RECONNECT unknown login ID\n");
516 
517 		req->status.status = cpu_to_be32(
518 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
519 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_ACCESS_DENIED));
520 		return;
521 	}
522 
523 	if (login->sess->guid != guid) {
524 		pr_err("mgt_agent RECONNECT login GUID doesn't match\n");
525 
526 		req->status.status = cpu_to_be32(
527 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
528 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_ACCESS_DENIED));
529 		return;
530 	}
531 
532 	spin_lock_bh(&login->sess->lock);
533 	if (login->sess->card)
534 		fw_card_put(login->sess->card);
535 
536 	/* update the node details */
537 	login->sess->generation = req->generation;
538 	login->sess->node_id = req->node_addr;
539 	login->sess->card = fw_card_get(req->card);
540 	login->sess->speed = req->speed;
541 	spin_unlock_bh(&login->sess->lock);
542 
543 	req->status.status = cpu_to_be32(
544 		STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
545 		STATUS_BLOCK_SBP_STATUS(SBP_STATUS_OK));
546 }
547 
548 static void sbp_management_request_logout(
549 	struct sbp_management_agent *agent, struct sbp_management_request *req,
550 	int *status_data_size)
551 {
552 	struct sbp_tport *tport = agent->tport;
553 	struct sbp_tpg *tpg = tport->tpg;
554 	int id;
555 	struct sbp_login_descriptor *login;
556 
557 	id = LOGOUT_ORB_LOGIN_ID(be32_to_cpu(req->orb.misc));
558 
559 	login = sbp_login_find_by_id(tpg, id);
560 	if (!login) {
561 		pr_warn("cannot find login: %d\n", id);
562 
563 		req->status.status = cpu_to_be32(
564 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
565 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_LOGIN_ID_UNKNOWN));
566 		return;
567 	}
568 
569 	pr_info("mgt_agent LOGOUT from LUN %d session %d\n",
570 		login->login_lun, login->login_id);
571 
572 	if (req->node_addr != login->sess->node_id) {
573 		pr_warn("logout from different node ID\n");
574 
575 		req->status.status = cpu_to_be32(
576 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
577 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_ACCESS_DENIED));
578 		return;
579 	}
580 
581 	sbp_login_release(login, true);
582 
583 	req->status.status = cpu_to_be32(
584 		STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
585 		STATUS_BLOCK_SBP_STATUS(SBP_STATUS_OK));
586 }
587 
588 static void session_check_for_reset(struct sbp_session *sess)
589 {
590 	bool card_valid = false;
591 
592 	spin_lock_bh(&sess->lock);
593 
594 	if (sess->card) {
595 		spin_lock_irq(&sess->card->lock);
596 		card_valid = (sess->card->local_node != NULL);
597 		spin_unlock_irq(&sess->card->lock);
598 
599 		if (!card_valid) {
600 			fw_card_put(sess->card);
601 			sess->card = NULL;
602 		}
603 	}
604 
605 	if (!card_valid || (sess->generation != sess->card->generation)) {
606 		pr_info("Waiting for reconnect from node: %016llx\n",
607 				sess->guid);
608 
609 		sess->node_id = -1;
610 		sess->reconnect_expires = get_jiffies_64() +
611 			((sess->reconnect_hold + 1) * HZ);
612 	}
613 
614 	spin_unlock_bh(&sess->lock);
615 }
616 
617 static void session_reconnect_expired(struct sbp_session *sess)
618 {
619 	struct sbp_login_descriptor *login, *temp;
620 	LIST_HEAD(login_list);
621 
622 	pr_info("Reconnect timer expired for node: %016llx\n", sess->guid);
623 
624 	spin_lock_bh(&sess->lock);
625 	list_for_each_entry_safe(login, temp, &sess->login_list, link) {
626 		login->sess = NULL;
627 		list_move_tail(&login->link, &login_list);
628 	}
629 	spin_unlock_bh(&sess->lock);
630 
631 	list_for_each_entry_safe(login, temp, &login_list, link) {
632 		list_del(&login->link);
633 		sbp_login_release(login, false);
634 	}
635 
636 	sbp_session_release(sess, false);
637 }
638 
639 static void session_maintenance_work(struct work_struct *work)
640 {
641 	struct sbp_session *sess = container_of(work, struct sbp_session,
642 			maint_work.work);
643 
644 	/* could be called while tearing down the session */
645 	spin_lock_bh(&sess->lock);
646 	if (list_empty(&sess->login_list)) {
647 		spin_unlock_bh(&sess->lock);
648 		return;
649 	}
650 	spin_unlock_bh(&sess->lock);
651 
652 	if (sess->node_id != -1) {
653 		/* check for bus reset and make node_id invalid */
654 		session_check_for_reset(sess);
655 
656 		schedule_delayed_work(&sess->maint_work,
657 				SESSION_MAINTENANCE_INTERVAL);
658 	} else if (!time_after64(get_jiffies_64(), sess->reconnect_expires)) {
659 		/* still waiting for reconnect */
660 		schedule_delayed_work(&sess->maint_work,
661 				SESSION_MAINTENANCE_INTERVAL);
662 	} else {
663 		/* reconnect timeout has expired */
664 		session_reconnect_expired(sess);
665 	}
666 }
667 
668 static int tgt_agent_rw_agent_state(struct fw_card *card, int tcode, void *data,
669 		struct sbp_target_agent *agent)
670 {
671 	int state;
672 
673 	switch (tcode) {
674 	case TCODE_READ_QUADLET_REQUEST:
675 		pr_debug("tgt_agent AGENT_STATE READ\n");
676 
677 		spin_lock_bh(&agent->lock);
678 		state = agent->state;
679 		spin_unlock_bh(&agent->lock);
680 
681 		*(__be32 *)data = cpu_to_be32(state);
682 
683 		return RCODE_COMPLETE;
684 
685 	case TCODE_WRITE_QUADLET_REQUEST:
686 		/* ignored */
687 		return RCODE_COMPLETE;
688 
689 	default:
690 		return RCODE_TYPE_ERROR;
691 	}
692 }
693 
694 static int tgt_agent_rw_agent_reset(struct fw_card *card, int tcode, void *data,
695 		struct sbp_target_agent *agent)
696 {
697 	switch (tcode) {
698 	case TCODE_WRITE_QUADLET_REQUEST:
699 		pr_debug("tgt_agent AGENT_RESET\n");
700 		spin_lock_bh(&agent->lock);
701 		agent->state = AGENT_STATE_RESET;
702 		spin_unlock_bh(&agent->lock);
703 		return RCODE_COMPLETE;
704 
705 	default:
706 		return RCODE_TYPE_ERROR;
707 	}
708 }
709 
710 static int tgt_agent_rw_orb_pointer(struct fw_card *card, int tcode, void *data,
711 		struct sbp_target_agent *agent)
712 {
713 	struct sbp2_pointer *ptr = data;
714 
715 	switch (tcode) {
716 	case TCODE_WRITE_BLOCK_REQUEST:
717 		spin_lock_bh(&agent->lock);
718 		if (agent->state != AGENT_STATE_SUSPENDED &&
719 				agent->state != AGENT_STATE_RESET) {
720 			spin_unlock_bh(&agent->lock);
721 			pr_notice("Ignoring ORB_POINTER write while active.\n");
722 			return RCODE_CONFLICT_ERROR;
723 		}
724 		agent->state = AGENT_STATE_ACTIVE;
725 		spin_unlock_bh(&agent->lock);
726 
727 		agent->orb_pointer = sbp2_pointer_to_addr(ptr);
728 		agent->doorbell = false;
729 
730 		pr_debug("tgt_agent ORB_POINTER write: 0x%llx\n",
731 				agent->orb_pointer);
732 
733 		queue_work(system_unbound_wq, &agent->work);
734 
735 		return RCODE_COMPLETE;
736 
737 	case TCODE_READ_BLOCK_REQUEST:
738 		pr_debug("tgt_agent ORB_POINTER READ\n");
739 		spin_lock_bh(&agent->lock);
740 		addr_to_sbp2_pointer(agent->orb_pointer, ptr);
741 		spin_unlock_bh(&agent->lock);
742 		return RCODE_COMPLETE;
743 
744 	default:
745 		return RCODE_TYPE_ERROR;
746 	}
747 }
748 
749 static int tgt_agent_rw_doorbell(struct fw_card *card, int tcode, void *data,
750 		struct sbp_target_agent *agent)
751 {
752 	switch (tcode) {
753 	case TCODE_WRITE_QUADLET_REQUEST:
754 		spin_lock_bh(&agent->lock);
755 		if (agent->state != AGENT_STATE_SUSPENDED) {
756 			spin_unlock_bh(&agent->lock);
757 			pr_debug("Ignoring DOORBELL while active.\n");
758 			return RCODE_CONFLICT_ERROR;
759 		}
760 		agent->state = AGENT_STATE_ACTIVE;
761 		spin_unlock_bh(&agent->lock);
762 
763 		agent->doorbell = true;
764 
765 		pr_debug("tgt_agent DOORBELL\n");
766 
767 		queue_work(system_unbound_wq, &agent->work);
768 
769 		return RCODE_COMPLETE;
770 
771 	case TCODE_READ_QUADLET_REQUEST:
772 		return RCODE_COMPLETE;
773 
774 	default:
775 		return RCODE_TYPE_ERROR;
776 	}
777 }
778 
779 static int tgt_agent_rw_unsolicited_status_enable(struct fw_card *card,
780 		int tcode, void *data, struct sbp_target_agent *agent)
781 {
782 	switch (tcode) {
783 	case TCODE_WRITE_QUADLET_REQUEST:
784 		pr_debug("tgt_agent UNSOLICITED_STATUS_ENABLE\n");
785 		/* ignored as we don't send unsolicited status */
786 		return RCODE_COMPLETE;
787 
788 	case TCODE_READ_QUADLET_REQUEST:
789 		return RCODE_COMPLETE;
790 
791 	default:
792 		return RCODE_TYPE_ERROR;
793 	}
794 }
795 
796 static void tgt_agent_rw(struct fw_card *card, struct fw_request *request,
797 		int tcode, int destination, int source, int generation,
798 		unsigned long long offset, void *data, size_t length,
799 		void *callback_data)
800 {
801 	struct sbp_target_agent *agent = callback_data;
802 	struct sbp_session *sess = agent->login->sess;
803 	int sess_gen, sess_node, rcode;
804 
805 	spin_lock_bh(&sess->lock);
806 	sess_gen = sess->generation;
807 	sess_node = sess->node_id;
808 	spin_unlock_bh(&sess->lock);
809 
810 	if (generation != sess_gen) {
811 		pr_notice("ignoring request with wrong generation\n");
812 		rcode = RCODE_TYPE_ERROR;
813 		goto out;
814 	}
815 
816 	if (source != sess_node) {
817 		pr_notice("ignoring request from foreign node (%x != %x)\n",
818 				source, sess_node);
819 		rcode = RCODE_TYPE_ERROR;
820 		goto out;
821 	}
822 
823 	/* turn offset into the offset from the start of the block */
824 	offset -= agent->handler.offset;
825 
826 	if (offset == 0x00 && length == 4) {
827 		/* AGENT_STATE */
828 		rcode = tgt_agent_rw_agent_state(card, tcode, data, agent);
829 	} else if (offset == 0x04 && length == 4) {
830 		/* AGENT_RESET */
831 		rcode = tgt_agent_rw_agent_reset(card, tcode, data, agent);
832 	} else if (offset == 0x08 && length == 8) {
833 		/* ORB_POINTER */
834 		rcode = tgt_agent_rw_orb_pointer(card, tcode, data, agent);
835 	} else if (offset == 0x10 && length == 4) {
836 		/* DOORBELL */
837 		rcode = tgt_agent_rw_doorbell(card, tcode, data, agent);
838 	} else if (offset == 0x14 && length == 4) {
839 		/* UNSOLICITED_STATUS_ENABLE */
840 		rcode = tgt_agent_rw_unsolicited_status_enable(card, tcode,
841 				data, agent);
842 	} else {
843 		rcode = RCODE_ADDRESS_ERROR;
844 	}
845 
846 out:
847 	fw_send_response(card, request, rcode);
848 }
849 
850 static void sbp_handle_command(struct sbp_target_request *);
851 static int sbp_send_status(struct sbp_target_request *);
852 static void sbp_free_request(struct sbp_target_request *);
853 
854 static void tgt_agent_process_work(struct work_struct *work)
855 {
856 	struct sbp_target_request *req =
857 		container_of(work, struct sbp_target_request, work);
858 
859 	pr_debug("tgt_orb ptr:0x%llx next_ORB:0x%llx data_descriptor:0x%llx misc:0x%x\n",
860 			req->orb_pointer,
861 			sbp2_pointer_to_addr(&req->orb.next_orb),
862 			sbp2_pointer_to_addr(&req->orb.data_descriptor),
863 			be32_to_cpu(req->orb.misc));
864 
865 	if (req->orb_pointer >> 32)
866 		pr_debug("ORB with high bits set\n");
867 
868 	switch (ORB_REQUEST_FORMAT(be32_to_cpu(req->orb.misc))) {
869 		case 0:/* Format specified by this standard */
870 			sbp_handle_command(req);
871 			return;
872 		case 1: /* Reserved for future standardization */
873 		case 2: /* Vendor-dependent */
874 			req->status.status |= cpu_to_be32(
875 					STATUS_BLOCK_RESP(
876 						STATUS_RESP_REQUEST_COMPLETE) |
877 					STATUS_BLOCK_DEAD(0) |
878 					STATUS_BLOCK_LEN(1) |
879 					STATUS_BLOCK_SBP_STATUS(
880 						SBP_STATUS_REQ_TYPE_NOTSUPP));
881 			sbp_send_status(req);
882 			return;
883 		case 3: /* Dummy ORB */
884 			req->status.status |= cpu_to_be32(
885 					STATUS_BLOCK_RESP(
886 						STATUS_RESP_REQUEST_COMPLETE) |
887 					STATUS_BLOCK_DEAD(0) |
888 					STATUS_BLOCK_LEN(1) |
889 					STATUS_BLOCK_SBP_STATUS(
890 						SBP_STATUS_DUMMY_ORB_COMPLETE));
891 			sbp_send_status(req);
892 			return;
893 		default:
894 			BUG();
895 	}
896 }
897 
898 /* used to double-check we haven't been issued an AGENT_RESET */
899 static inline bool tgt_agent_check_active(struct sbp_target_agent *agent)
900 {
901 	bool active;
902 
903 	spin_lock_bh(&agent->lock);
904 	active = (agent->state == AGENT_STATE_ACTIVE);
905 	spin_unlock_bh(&agent->lock);
906 
907 	return active;
908 }
909 
910 static struct sbp_target_request *sbp_mgt_get_req(struct sbp_session *sess,
911 	struct fw_card *card, u64 next_orb)
912 {
913 	struct se_session *se_sess = sess->se_sess;
914 	struct sbp_target_request *req;
915 	int tag, cpu;
916 
917 	tag = sbitmap_queue_get(&se_sess->sess_tag_pool, &cpu);
918 	if (tag < 0)
919 		return ERR_PTR(-ENOMEM);
920 
921 	req = &((struct sbp_target_request *)se_sess->sess_cmd_map)[tag];
922 	memset(req, 0, sizeof(*req));
923 	req->se_cmd.map_tag = tag;
924 	req->se_cmd.map_cpu = cpu;
925 	req->se_cmd.tag = next_orb;
926 
927 	return req;
928 }
929 
930 static void tgt_agent_fetch_work(struct work_struct *work)
931 {
932 	struct sbp_target_agent *agent =
933 		container_of(work, struct sbp_target_agent, work);
934 	struct sbp_session *sess = agent->login->sess;
935 	struct sbp_target_request *req;
936 	int ret;
937 	bool doorbell = agent->doorbell;
938 	u64 next_orb = agent->orb_pointer;
939 
940 	while (next_orb && tgt_agent_check_active(agent)) {
941 		req = sbp_mgt_get_req(sess, sess->card, next_orb);
942 		if (IS_ERR(req)) {
943 			spin_lock_bh(&agent->lock);
944 			agent->state = AGENT_STATE_DEAD;
945 			spin_unlock_bh(&agent->lock);
946 			return;
947 		}
948 
949 		req->login = agent->login;
950 		req->orb_pointer = next_orb;
951 
952 		req->status.status = cpu_to_be32(STATUS_BLOCK_ORB_OFFSET_HIGH(
953 					req->orb_pointer >> 32));
954 		req->status.orb_low = cpu_to_be32(
955 				req->orb_pointer & 0xfffffffc);
956 
957 		/* read in the ORB */
958 		ret = sbp_run_transaction(sess->card, TCODE_READ_BLOCK_REQUEST,
959 				sess->node_id, sess->generation, sess->speed,
960 				req->orb_pointer, &req->orb, sizeof(req->orb));
961 		if (ret != RCODE_COMPLETE) {
962 			pr_debug("tgt_orb fetch failed: %x\n", ret);
963 			req->status.status |= cpu_to_be32(
964 					STATUS_BLOCK_SRC(
965 						STATUS_SRC_ORB_FINISHED) |
966 					STATUS_BLOCK_RESP(
967 						STATUS_RESP_TRANSPORT_FAILURE) |
968 					STATUS_BLOCK_DEAD(1) |
969 					STATUS_BLOCK_LEN(1) |
970 					STATUS_BLOCK_SBP_STATUS(
971 						SBP_STATUS_UNSPECIFIED_ERROR));
972 			spin_lock_bh(&agent->lock);
973 			agent->state = AGENT_STATE_DEAD;
974 			spin_unlock_bh(&agent->lock);
975 
976 			sbp_send_status(req);
977 			return;
978 		}
979 
980 		/* check the next_ORB field */
981 		if (be32_to_cpu(req->orb.next_orb.high) & 0x80000000) {
982 			next_orb = 0;
983 			req->status.status |= cpu_to_be32(STATUS_BLOCK_SRC(
984 						STATUS_SRC_ORB_FINISHED));
985 		} else {
986 			next_orb = sbp2_pointer_to_addr(&req->orb.next_orb);
987 			req->status.status |= cpu_to_be32(STATUS_BLOCK_SRC(
988 						STATUS_SRC_ORB_CONTINUING));
989 		}
990 
991 		if (tgt_agent_check_active(agent) && !doorbell) {
992 			INIT_WORK(&req->work, tgt_agent_process_work);
993 			queue_work(system_unbound_wq, &req->work);
994 		} else {
995 			/* don't process this request, just check next_ORB */
996 			sbp_free_request(req);
997 		}
998 
999 		spin_lock_bh(&agent->lock);
1000 		doorbell = agent->doorbell = false;
1001 
1002 		/* check if we should carry on processing */
1003 		if (next_orb)
1004 			agent->orb_pointer = next_orb;
1005 		else
1006 			agent->state = AGENT_STATE_SUSPENDED;
1007 
1008 		spin_unlock_bh(&agent->lock);
1009 	}
1010 }
1011 
1012 static struct sbp_target_agent *sbp_target_agent_register(
1013 		struct sbp_login_descriptor *login)
1014 {
1015 	struct sbp_target_agent *agent;
1016 	int ret;
1017 
1018 	agent = kmalloc(sizeof(*agent), GFP_KERNEL);
1019 	if (!agent)
1020 		return ERR_PTR(-ENOMEM);
1021 
1022 	spin_lock_init(&agent->lock);
1023 
1024 	agent->handler.length = 0x20;
1025 	agent->handler.address_callback = tgt_agent_rw;
1026 	agent->handler.callback_data = agent;
1027 
1028 	agent->login = login;
1029 	agent->state = AGENT_STATE_RESET;
1030 	INIT_WORK(&agent->work, tgt_agent_fetch_work);
1031 	agent->orb_pointer = 0;
1032 	agent->doorbell = false;
1033 
1034 	ret = fw_core_add_address_handler(&agent->handler,
1035 			&sbp_register_region);
1036 	if (ret < 0) {
1037 		kfree(agent);
1038 		return ERR_PTR(ret);
1039 	}
1040 
1041 	return agent;
1042 }
1043 
1044 static void sbp_target_agent_unregister(struct sbp_target_agent *agent)
1045 {
1046 	fw_core_remove_address_handler(&agent->handler);
1047 	cancel_work_sync(&agent->work);
1048 	kfree(agent);
1049 }
1050 
1051 /*
1052  * Simple wrapper around fw_run_transaction that retries the transaction several
1053  * times in case of failure, with an exponential backoff.
1054  */
1055 static int sbp_run_transaction(struct fw_card *card, int tcode, int destination_id,
1056 		int generation, int speed, unsigned long long offset,
1057 		void *payload, size_t length)
1058 {
1059 	int attempt, ret, delay;
1060 
1061 	for (attempt = 1; attempt <= 5; attempt++) {
1062 		ret = fw_run_transaction(card, tcode, destination_id,
1063 				generation, speed, offset, payload, length);
1064 
1065 		switch (ret) {
1066 		case RCODE_COMPLETE:
1067 		case RCODE_TYPE_ERROR:
1068 		case RCODE_ADDRESS_ERROR:
1069 		case RCODE_GENERATION:
1070 			return ret;
1071 
1072 		default:
1073 			delay = 5 * attempt * attempt;
1074 			usleep_range(delay, delay * 2);
1075 		}
1076 	}
1077 
1078 	return ret;
1079 }
1080 
1081 /*
1082  * Wrapper around sbp_run_transaction that gets the card, destination,
1083  * generation and speed out of the request's session.
1084  */
1085 static int sbp_run_request_transaction(struct sbp_target_request *req,
1086 		int tcode, unsigned long long offset, void *payload,
1087 		size_t length)
1088 {
1089 	struct sbp_login_descriptor *login = req->login;
1090 	struct sbp_session *sess = login->sess;
1091 	struct fw_card *card;
1092 	int node_id, generation, speed, ret;
1093 
1094 	spin_lock_bh(&sess->lock);
1095 	card = fw_card_get(sess->card);
1096 	node_id = sess->node_id;
1097 	generation = sess->generation;
1098 	speed = sess->speed;
1099 	spin_unlock_bh(&sess->lock);
1100 
1101 	ret = sbp_run_transaction(card, tcode, node_id, generation, speed,
1102 			offset, payload, length);
1103 
1104 	fw_card_put(card);
1105 
1106 	return ret;
1107 }
1108 
1109 static int sbp_fetch_command(struct sbp_target_request *req)
1110 {
1111 	int ret, cmd_len, copy_len;
1112 
1113 	cmd_len = scsi_command_size(req->orb.command_block);
1114 
1115 	req->cmd_buf = kmalloc(cmd_len, GFP_KERNEL);
1116 	if (!req->cmd_buf)
1117 		return -ENOMEM;
1118 
1119 	memcpy(req->cmd_buf, req->orb.command_block,
1120 		min_t(int, cmd_len, sizeof(req->orb.command_block)));
1121 
1122 	if (cmd_len > sizeof(req->orb.command_block)) {
1123 		pr_debug("sbp_fetch_command: filling in long command\n");
1124 		copy_len = cmd_len - sizeof(req->orb.command_block);
1125 
1126 		ret = sbp_run_request_transaction(req,
1127 				TCODE_READ_BLOCK_REQUEST,
1128 				req->orb_pointer + sizeof(req->orb),
1129 				req->cmd_buf + sizeof(req->orb.command_block),
1130 				copy_len);
1131 		if (ret != RCODE_COMPLETE)
1132 			return -EIO;
1133 	}
1134 
1135 	return 0;
1136 }
1137 
1138 static int sbp_fetch_page_table(struct sbp_target_request *req)
1139 {
1140 	int pg_tbl_sz, ret;
1141 	struct sbp_page_table_entry *pg_tbl;
1142 
1143 	if (!CMDBLK_ORB_PG_TBL_PRESENT(be32_to_cpu(req->orb.misc)))
1144 		return 0;
1145 
1146 	pg_tbl_sz = CMDBLK_ORB_DATA_SIZE(be32_to_cpu(req->orb.misc)) *
1147 		sizeof(struct sbp_page_table_entry);
1148 
1149 	pg_tbl = kmalloc(pg_tbl_sz, GFP_KERNEL);
1150 	if (!pg_tbl)
1151 		return -ENOMEM;
1152 
1153 	ret = sbp_run_request_transaction(req, TCODE_READ_BLOCK_REQUEST,
1154 			sbp2_pointer_to_addr(&req->orb.data_descriptor),
1155 			pg_tbl, pg_tbl_sz);
1156 	if (ret != RCODE_COMPLETE) {
1157 		kfree(pg_tbl);
1158 		return -EIO;
1159 	}
1160 
1161 	req->pg_tbl = pg_tbl;
1162 	return 0;
1163 }
1164 
1165 static void sbp_calc_data_length_direction(struct sbp_target_request *req,
1166 	u32 *data_len, enum dma_data_direction *data_dir)
1167 {
1168 	int data_size, direction, idx;
1169 
1170 	data_size = CMDBLK_ORB_DATA_SIZE(be32_to_cpu(req->orb.misc));
1171 	direction = CMDBLK_ORB_DIRECTION(be32_to_cpu(req->orb.misc));
1172 
1173 	if (!data_size) {
1174 		*data_len = 0;
1175 		*data_dir = DMA_NONE;
1176 		return;
1177 	}
1178 
1179 	*data_dir = direction ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1180 
1181 	if (req->pg_tbl) {
1182 		*data_len = 0;
1183 		for (idx = 0; idx < data_size; idx++) {
1184 			*data_len += be16_to_cpu(
1185 					req->pg_tbl[idx].segment_length);
1186 		}
1187 	} else {
1188 		*data_len = data_size;
1189 	}
1190 }
1191 
1192 static void sbp_handle_command(struct sbp_target_request *req)
1193 {
1194 	struct sbp_login_descriptor *login = req->login;
1195 	struct sbp_session *sess = login->sess;
1196 	int ret, unpacked_lun;
1197 	u32 data_length;
1198 	enum dma_data_direction data_dir;
1199 
1200 	ret = sbp_fetch_command(req);
1201 	if (ret) {
1202 		pr_debug("sbp_handle_command: fetch command failed: %d\n", ret);
1203 		goto err;
1204 	}
1205 
1206 	ret = sbp_fetch_page_table(req);
1207 	if (ret) {
1208 		pr_debug("sbp_handle_command: fetch page table failed: %d\n",
1209 			ret);
1210 		goto err;
1211 	}
1212 
1213 	unpacked_lun = req->login->login_lun;
1214 	sbp_calc_data_length_direction(req, &data_length, &data_dir);
1215 
1216 	pr_debug("sbp_handle_command ORB:0x%llx unpacked_lun:%d data_len:%d data_dir:%d\n",
1217 			req->orb_pointer, unpacked_lun, data_length, data_dir);
1218 
1219 	/* only used for printk until we do TMRs */
1220 	req->se_cmd.tag = req->orb_pointer;
1221 	target_submit_cmd(&req->se_cmd, sess->se_sess, req->cmd_buf,
1222 			  req->sense_buf, unpacked_lun, data_length,
1223 			  TCM_SIMPLE_TAG, data_dir, TARGET_SCF_ACK_KREF);
1224 	return;
1225 
1226 err:
1227 	req->status.status |= cpu_to_be32(
1228 		STATUS_BLOCK_RESP(STATUS_RESP_TRANSPORT_FAILURE) |
1229 		STATUS_BLOCK_DEAD(0) |
1230 		STATUS_BLOCK_LEN(1) |
1231 		STATUS_BLOCK_SBP_STATUS(SBP_STATUS_UNSPECIFIED_ERROR));
1232 	sbp_send_status(req);
1233 }
1234 
1235 /*
1236  * DMA_TO_DEVICE = read from initiator (SCSI WRITE)
1237  * DMA_FROM_DEVICE = write to initiator (SCSI READ)
1238  */
1239 static int sbp_rw_data(struct sbp_target_request *req)
1240 {
1241 	struct sbp_session *sess = req->login->sess;
1242 	int tcode, sg_miter_flags, max_payload, pg_size, speed, node_id,
1243 		generation, num_pte, length, tfr_length,
1244 		rcode = RCODE_COMPLETE;
1245 	struct sbp_page_table_entry *pte;
1246 	unsigned long long offset;
1247 	struct fw_card *card;
1248 	struct sg_mapping_iter iter;
1249 
1250 	if (req->se_cmd.data_direction == DMA_FROM_DEVICE) {
1251 		tcode = TCODE_WRITE_BLOCK_REQUEST;
1252 		sg_miter_flags = SG_MITER_FROM_SG;
1253 	} else {
1254 		tcode = TCODE_READ_BLOCK_REQUEST;
1255 		sg_miter_flags = SG_MITER_TO_SG;
1256 	}
1257 
1258 	max_payload = 4 << CMDBLK_ORB_MAX_PAYLOAD(be32_to_cpu(req->orb.misc));
1259 	speed = CMDBLK_ORB_SPEED(be32_to_cpu(req->orb.misc));
1260 
1261 	pg_size = CMDBLK_ORB_PG_SIZE(be32_to_cpu(req->orb.misc));
1262 	if (pg_size) {
1263 		pr_err("sbp_run_transaction: page size ignored\n");
1264 	}
1265 
1266 	spin_lock_bh(&sess->lock);
1267 	card = fw_card_get(sess->card);
1268 	node_id = sess->node_id;
1269 	generation = sess->generation;
1270 	spin_unlock_bh(&sess->lock);
1271 
1272 	if (req->pg_tbl) {
1273 		pte = req->pg_tbl;
1274 		num_pte = CMDBLK_ORB_DATA_SIZE(be32_to_cpu(req->orb.misc));
1275 
1276 		offset = 0;
1277 		length = 0;
1278 	} else {
1279 		pte = NULL;
1280 		num_pte = 0;
1281 
1282 		offset = sbp2_pointer_to_addr(&req->orb.data_descriptor);
1283 		length = req->se_cmd.data_length;
1284 	}
1285 
1286 	sg_miter_start(&iter, req->se_cmd.t_data_sg, req->se_cmd.t_data_nents,
1287 		sg_miter_flags);
1288 
1289 	while (length || num_pte) {
1290 		if (!length) {
1291 			offset = (u64)be16_to_cpu(pte->segment_base_hi) << 32 |
1292 				be32_to_cpu(pte->segment_base_lo);
1293 			length = be16_to_cpu(pte->segment_length);
1294 
1295 			pte++;
1296 			num_pte--;
1297 		}
1298 
1299 		sg_miter_next(&iter);
1300 
1301 		tfr_length = min3(length, max_payload, (int)iter.length);
1302 
1303 		/* FIXME: take page_size into account */
1304 
1305 		rcode = sbp_run_transaction(card, tcode, node_id,
1306 				generation, speed,
1307 				offset, iter.addr, tfr_length);
1308 
1309 		if (rcode != RCODE_COMPLETE)
1310 			break;
1311 
1312 		length -= tfr_length;
1313 		offset += tfr_length;
1314 		iter.consumed = tfr_length;
1315 	}
1316 
1317 	sg_miter_stop(&iter);
1318 	fw_card_put(card);
1319 
1320 	if (rcode == RCODE_COMPLETE) {
1321 		WARN_ON(length != 0);
1322 		return 0;
1323 	} else {
1324 		return -EIO;
1325 	}
1326 }
1327 
1328 static int sbp_send_status(struct sbp_target_request *req)
1329 {
1330 	int rc, ret = 0, length;
1331 	struct sbp_login_descriptor *login = req->login;
1332 
1333 	length = (((be32_to_cpu(req->status.status) >> 24) & 0x07) + 1) * 4;
1334 
1335 	rc = sbp_run_request_transaction(req, TCODE_WRITE_BLOCK_REQUEST,
1336 			login->status_fifo_addr, &req->status, length);
1337 	if (rc != RCODE_COMPLETE) {
1338 		pr_debug("sbp_send_status: write failed: 0x%x\n", rc);
1339 		ret = -EIO;
1340 		goto put_ref;
1341 	}
1342 
1343 	pr_debug("sbp_send_status: status write complete for ORB: 0x%llx\n",
1344 			req->orb_pointer);
1345 	/*
1346 	 * Drop the extra ACK_KREF reference taken by target_submit_cmd()
1347 	 * ahead of sbp_check_stop_free() -> transport_generic_free_cmd()
1348 	 * final se_cmd->cmd_kref put.
1349 	 */
1350 put_ref:
1351 	target_put_sess_cmd(&req->se_cmd);
1352 	return ret;
1353 }
1354 
1355 static void sbp_sense_mangle(struct sbp_target_request *req)
1356 {
1357 	struct se_cmd *se_cmd = &req->se_cmd;
1358 	u8 *sense = req->sense_buf;
1359 	u8 *status = req->status.data;
1360 
1361 	WARN_ON(se_cmd->scsi_sense_length < 18);
1362 
1363 	switch (sense[0] & 0x7f) { 		/* sfmt */
1364 	case 0x70: /* current, fixed */
1365 		status[0] = 0 << 6;
1366 		break;
1367 	case 0x71: /* deferred, fixed */
1368 		status[0] = 1 << 6;
1369 		break;
1370 	case 0x72: /* current, descriptor */
1371 	case 0x73: /* deferred, descriptor */
1372 	default:
1373 		/*
1374 		 * TODO: SBP-3 specifies what we should do with descriptor
1375 		 * format sense data
1376 		 */
1377 		pr_err("sbp_send_sense: unknown sense format: 0x%x\n",
1378 			sense[0]);
1379 		req->status.status |= cpu_to_be32(
1380 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
1381 			STATUS_BLOCK_DEAD(0) |
1382 			STATUS_BLOCK_LEN(1) |
1383 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_REQUEST_ABORTED));
1384 		return;
1385 	}
1386 
1387 	status[0] |= se_cmd->scsi_status & 0x3f;/* status */
1388 	status[1] =
1389 		(sense[0] & 0x80) |		/* valid */
1390 		((sense[2] & 0xe0) >> 1) |	/* mark, eom, ili */
1391 		(sense[2] & 0x0f);		/* sense_key */
1392 	status[2] = 0;				/* XXX sense_code */
1393 	status[3] = 0;				/* XXX sense_qualifier */
1394 
1395 	/* information */
1396 	status[4] = sense[3];
1397 	status[5] = sense[4];
1398 	status[6] = sense[5];
1399 	status[7] = sense[6];
1400 
1401 	/* CDB-dependent */
1402 	status[8] = sense[8];
1403 	status[9] = sense[9];
1404 	status[10] = sense[10];
1405 	status[11] = sense[11];
1406 
1407 	/* fru */
1408 	status[12] = sense[14];
1409 
1410 	/* sense_key-dependent */
1411 	status[13] = sense[15];
1412 	status[14] = sense[16];
1413 	status[15] = sense[17];
1414 
1415 	req->status.status |= cpu_to_be32(
1416 		STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
1417 		STATUS_BLOCK_DEAD(0) |
1418 		STATUS_BLOCK_LEN(5) |
1419 		STATUS_BLOCK_SBP_STATUS(SBP_STATUS_OK));
1420 }
1421 
1422 static int sbp_send_sense(struct sbp_target_request *req)
1423 {
1424 	struct se_cmd *se_cmd = &req->se_cmd;
1425 
1426 	if (se_cmd->scsi_sense_length) {
1427 		sbp_sense_mangle(req);
1428 	} else {
1429 		req->status.status |= cpu_to_be32(
1430 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
1431 			STATUS_BLOCK_DEAD(0) |
1432 			STATUS_BLOCK_LEN(1) |
1433 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_OK));
1434 	}
1435 
1436 	return sbp_send_status(req);
1437 }
1438 
1439 static void sbp_free_request(struct sbp_target_request *req)
1440 {
1441 	struct se_cmd *se_cmd = &req->se_cmd;
1442 	struct se_session *se_sess = se_cmd->se_sess;
1443 
1444 	kfree(req->pg_tbl);
1445 	kfree(req->cmd_buf);
1446 
1447 	target_free_tag(se_sess, se_cmd);
1448 }
1449 
1450 static void sbp_mgt_agent_process(struct work_struct *work)
1451 {
1452 	struct sbp_management_agent *agent =
1453 		container_of(work, struct sbp_management_agent, work);
1454 	struct sbp_management_request *req = agent->request;
1455 	int ret;
1456 	int status_data_len = 0;
1457 
1458 	/* fetch the ORB from the initiator */
1459 	ret = sbp_run_transaction(req->card, TCODE_READ_BLOCK_REQUEST,
1460 		req->node_addr, req->generation, req->speed,
1461 		agent->orb_offset, &req->orb, sizeof(req->orb));
1462 	if (ret != RCODE_COMPLETE) {
1463 		pr_debug("mgt_orb fetch failed: %x\n", ret);
1464 		goto out;
1465 	}
1466 
1467 	pr_debug("mgt_orb ptr1:0x%llx ptr2:0x%llx misc:0x%x len:0x%x status_fifo:0x%llx\n",
1468 		sbp2_pointer_to_addr(&req->orb.ptr1),
1469 		sbp2_pointer_to_addr(&req->orb.ptr2),
1470 		be32_to_cpu(req->orb.misc), be32_to_cpu(req->orb.length),
1471 		sbp2_pointer_to_addr(&req->orb.status_fifo));
1472 
1473 	if (!ORB_NOTIFY(be32_to_cpu(req->orb.misc)) ||
1474 		ORB_REQUEST_FORMAT(be32_to_cpu(req->orb.misc)) != 0) {
1475 		pr_err("mgt_orb bad request\n");
1476 		goto out;
1477 	}
1478 
1479 	switch (MANAGEMENT_ORB_FUNCTION(be32_to_cpu(req->orb.misc))) {
1480 	case MANAGEMENT_ORB_FUNCTION_LOGIN:
1481 		sbp_management_request_login(agent, req, &status_data_len);
1482 		break;
1483 
1484 	case MANAGEMENT_ORB_FUNCTION_QUERY_LOGINS:
1485 		sbp_management_request_query_logins(agent, req,
1486 				&status_data_len);
1487 		break;
1488 
1489 	case MANAGEMENT_ORB_FUNCTION_RECONNECT:
1490 		sbp_management_request_reconnect(agent, req, &status_data_len);
1491 		break;
1492 
1493 	case MANAGEMENT_ORB_FUNCTION_SET_PASSWORD:
1494 		pr_notice("SET PASSWORD not implemented\n");
1495 
1496 		req->status.status = cpu_to_be32(
1497 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
1498 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_REQ_TYPE_NOTSUPP));
1499 
1500 		break;
1501 
1502 	case MANAGEMENT_ORB_FUNCTION_LOGOUT:
1503 		sbp_management_request_logout(agent, req, &status_data_len);
1504 		break;
1505 
1506 	case MANAGEMENT_ORB_FUNCTION_ABORT_TASK:
1507 		pr_notice("ABORT TASK not implemented\n");
1508 
1509 		req->status.status = cpu_to_be32(
1510 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
1511 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_REQ_TYPE_NOTSUPP));
1512 
1513 		break;
1514 
1515 	case MANAGEMENT_ORB_FUNCTION_ABORT_TASK_SET:
1516 		pr_notice("ABORT TASK SET not implemented\n");
1517 
1518 		req->status.status = cpu_to_be32(
1519 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
1520 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_REQ_TYPE_NOTSUPP));
1521 
1522 		break;
1523 
1524 	case MANAGEMENT_ORB_FUNCTION_LOGICAL_UNIT_RESET:
1525 		pr_notice("LOGICAL UNIT RESET not implemented\n");
1526 
1527 		req->status.status = cpu_to_be32(
1528 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
1529 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_REQ_TYPE_NOTSUPP));
1530 
1531 		break;
1532 
1533 	case MANAGEMENT_ORB_FUNCTION_TARGET_RESET:
1534 		pr_notice("TARGET RESET not implemented\n");
1535 
1536 		req->status.status = cpu_to_be32(
1537 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
1538 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_REQ_TYPE_NOTSUPP));
1539 
1540 		break;
1541 
1542 	default:
1543 		pr_notice("unknown management function 0x%x\n",
1544 			MANAGEMENT_ORB_FUNCTION(be32_to_cpu(req->orb.misc)));
1545 
1546 		req->status.status = cpu_to_be32(
1547 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
1548 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_REQ_TYPE_NOTSUPP));
1549 
1550 		break;
1551 	}
1552 
1553 	req->status.status |= cpu_to_be32(
1554 		STATUS_BLOCK_SRC(1) | /* Response to ORB, next_ORB absent */
1555 		STATUS_BLOCK_LEN(DIV_ROUND_UP(status_data_len, 4) + 1) |
1556 		STATUS_BLOCK_ORB_OFFSET_HIGH(agent->orb_offset >> 32));
1557 	req->status.orb_low = cpu_to_be32(agent->orb_offset);
1558 
1559 	/* write the status block back to the initiator */
1560 	ret = sbp_run_transaction(req->card, TCODE_WRITE_BLOCK_REQUEST,
1561 		req->node_addr, req->generation, req->speed,
1562 		sbp2_pointer_to_addr(&req->orb.status_fifo),
1563 		&req->status, 8 + status_data_len);
1564 	if (ret != RCODE_COMPLETE) {
1565 		pr_debug("mgt_orb status write failed: %x\n", ret);
1566 		goto out;
1567 	}
1568 
1569 out:
1570 	fw_card_put(req->card);
1571 	kfree(req);
1572 
1573 	spin_lock_bh(&agent->lock);
1574 	agent->state = MANAGEMENT_AGENT_STATE_IDLE;
1575 	spin_unlock_bh(&agent->lock);
1576 }
1577 
1578 static void sbp_mgt_agent_rw(struct fw_card *card,
1579 	struct fw_request *request, int tcode, int destination, int source,
1580 	int generation, unsigned long long offset, void *data, size_t length,
1581 	void *callback_data)
1582 {
1583 	struct sbp_management_agent *agent = callback_data;
1584 	struct sbp2_pointer *ptr = data;
1585 	int rcode = RCODE_ADDRESS_ERROR;
1586 
1587 	if (!agent->tport->enable)
1588 		goto out;
1589 
1590 	if ((offset != agent->handler.offset) || (length != 8))
1591 		goto out;
1592 
1593 	if (tcode == TCODE_WRITE_BLOCK_REQUEST) {
1594 		struct sbp_management_request *req;
1595 		int prev_state;
1596 
1597 		spin_lock_bh(&agent->lock);
1598 		prev_state = agent->state;
1599 		agent->state = MANAGEMENT_AGENT_STATE_BUSY;
1600 		spin_unlock_bh(&agent->lock);
1601 
1602 		if (prev_state == MANAGEMENT_AGENT_STATE_BUSY) {
1603 			pr_notice("ignoring management request while busy\n");
1604 			rcode = RCODE_CONFLICT_ERROR;
1605 			goto out;
1606 		}
1607 		req = kzalloc(sizeof(*req), GFP_ATOMIC);
1608 		if (!req) {
1609 			rcode = RCODE_CONFLICT_ERROR;
1610 			goto out;
1611 		}
1612 
1613 		req->card = fw_card_get(card);
1614 		req->generation = generation;
1615 		req->node_addr = source;
1616 		req->speed = fw_get_request_speed(request);
1617 
1618 		agent->orb_offset = sbp2_pointer_to_addr(ptr);
1619 		agent->request = req;
1620 
1621 		queue_work(system_unbound_wq, &agent->work);
1622 		rcode = RCODE_COMPLETE;
1623 	} else if (tcode == TCODE_READ_BLOCK_REQUEST) {
1624 		addr_to_sbp2_pointer(agent->orb_offset, ptr);
1625 		rcode = RCODE_COMPLETE;
1626 	} else {
1627 		rcode = RCODE_TYPE_ERROR;
1628 	}
1629 
1630 out:
1631 	fw_send_response(card, request, rcode);
1632 }
1633 
1634 static struct sbp_management_agent *sbp_management_agent_register(
1635 		struct sbp_tport *tport)
1636 {
1637 	int ret;
1638 	struct sbp_management_agent *agent;
1639 
1640 	agent = kmalloc(sizeof(*agent), GFP_KERNEL);
1641 	if (!agent)
1642 		return ERR_PTR(-ENOMEM);
1643 
1644 	spin_lock_init(&agent->lock);
1645 	agent->tport = tport;
1646 	agent->handler.length = 0x08;
1647 	agent->handler.address_callback = sbp_mgt_agent_rw;
1648 	agent->handler.callback_data = agent;
1649 	agent->state = MANAGEMENT_AGENT_STATE_IDLE;
1650 	INIT_WORK(&agent->work, sbp_mgt_agent_process);
1651 	agent->orb_offset = 0;
1652 	agent->request = NULL;
1653 
1654 	ret = fw_core_add_address_handler(&agent->handler,
1655 			&sbp_register_region);
1656 	if (ret < 0) {
1657 		kfree(agent);
1658 		return ERR_PTR(ret);
1659 	}
1660 
1661 	return agent;
1662 }
1663 
1664 static void sbp_management_agent_unregister(struct sbp_management_agent *agent)
1665 {
1666 	fw_core_remove_address_handler(&agent->handler);
1667 	cancel_work_sync(&agent->work);
1668 	kfree(agent);
1669 }
1670 
1671 static int sbp_check_true(struct se_portal_group *se_tpg)
1672 {
1673 	return 1;
1674 }
1675 
1676 static int sbp_check_false(struct se_portal_group *se_tpg)
1677 {
1678 	return 0;
1679 }
1680 
1681 static char *sbp_get_fabric_wwn(struct se_portal_group *se_tpg)
1682 {
1683 	struct sbp_tpg *tpg = container_of(se_tpg, struct sbp_tpg, se_tpg);
1684 	struct sbp_tport *tport = tpg->tport;
1685 
1686 	return &tport->tport_name[0];
1687 }
1688 
1689 static u16 sbp_get_tag(struct se_portal_group *se_tpg)
1690 {
1691 	struct sbp_tpg *tpg = container_of(se_tpg, struct sbp_tpg, se_tpg);
1692 	return tpg->tport_tpgt;
1693 }
1694 
1695 static u32 sbp_tpg_get_inst_index(struct se_portal_group *se_tpg)
1696 {
1697 	return 1;
1698 }
1699 
1700 static void sbp_release_cmd(struct se_cmd *se_cmd)
1701 {
1702 	struct sbp_target_request *req = container_of(se_cmd,
1703 			struct sbp_target_request, se_cmd);
1704 
1705 	sbp_free_request(req);
1706 }
1707 
1708 static u32 sbp_sess_get_index(struct se_session *se_sess)
1709 {
1710 	return 0;
1711 }
1712 
1713 static int sbp_write_pending(struct se_cmd *se_cmd)
1714 {
1715 	struct sbp_target_request *req = container_of(se_cmd,
1716 			struct sbp_target_request, se_cmd);
1717 	int ret;
1718 
1719 	ret = sbp_rw_data(req);
1720 	if (ret) {
1721 		req->status.status |= cpu_to_be32(
1722 			STATUS_BLOCK_RESP(
1723 				STATUS_RESP_TRANSPORT_FAILURE) |
1724 			STATUS_BLOCK_DEAD(0) |
1725 			STATUS_BLOCK_LEN(1) |
1726 			STATUS_BLOCK_SBP_STATUS(
1727 				SBP_STATUS_UNSPECIFIED_ERROR));
1728 		sbp_send_status(req);
1729 		return ret;
1730 	}
1731 
1732 	target_execute_cmd(se_cmd);
1733 	return 0;
1734 }
1735 
1736 static void sbp_set_default_node_attrs(struct se_node_acl *nacl)
1737 {
1738 	return;
1739 }
1740 
1741 static int sbp_get_cmd_state(struct se_cmd *se_cmd)
1742 {
1743 	return 0;
1744 }
1745 
1746 static int sbp_queue_data_in(struct se_cmd *se_cmd)
1747 {
1748 	struct sbp_target_request *req = container_of(se_cmd,
1749 			struct sbp_target_request, se_cmd);
1750 	int ret;
1751 
1752 	ret = sbp_rw_data(req);
1753 	if (ret) {
1754 		req->status.status |= cpu_to_be32(
1755 			STATUS_BLOCK_RESP(STATUS_RESP_TRANSPORT_FAILURE) |
1756 			STATUS_BLOCK_DEAD(0) |
1757 			STATUS_BLOCK_LEN(1) |
1758 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_UNSPECIFIED_ERROR));
1759 		sbp_send_status(req);
1760 		return ret;
1761 	}
1762 
1763 	return sbp_send_sense(req);
1764 }
1765 
1766 /*
1767  * Called after command (no data transfer) or after the write (to device)
1768  * operation is completed
1769  */
1770 static int sbp_queue_status(struct se_cmd *se_cmd)
1771 {
1772 	struct sbp_target_request *req = container_of(se_cmd,
1773 			struct sbp_target_request, se_cmd);
1774 
1775 	return sbp_send_sense(req);
1776 }
1777 
1778 static void sbp_queue_tm_rsp(struct se_cmd *se_cmd)
1779 {
1780 }
1781 
1782 static void sbp_aborted_task(struct se_cmd *se_cmd)
1783 {
1784 	return;
1785 }
1786 
1787 static int sbp_check_stop_free(struct se_cmd *se_cmd)
1788 {
1789 	struct sbp_target_request *req = container_of(se_cmd,
1790 			struct sbp_target_request, se_cmd);
1791 
1792 	return transport_generic_free_cmd(&req->se_cmd, 0);
1793 }
1794 
1795 static int sbp_count_se_tpg_luns(struct se_portal_group *tpg)
1796 {
1797 	struct se_lun *lun;
1798 	int count = 0;
1799 
1800 	rcu_read_lock();
1801 	hlist_for_each_entry_rcu(lun, &tpg->tpg_lun_hlist, link)
1802 		count++;
1803 	rcu_read_unlock();
1804 
1805 	return count;
1806 }
1807 
1808 static int sbp_update_unit_directory(struct sbp_tport *tport)
1809 {
1810 	struct se_lun *lun;
1811 	int num_luns, num_entries, idx = 0, mgt_agt_addr, ret;
1812 	u32 *data;
1813 
1814 	if (tport->unit_directory.data) {
1815 		fw_core_remove_descriptor(&tport->unit_directory);
1816 		kfree(tport->unit_directory.data);
1817 		tport->unit_directory.data = NULL;
1818 	}
1819 
1820 	if (!tport->enable || !tport->tpg)
1821 		return 0;
1822 
1823 	num_luns = sbp_count_se_tpg_luns(&tport->tpg->se_tpg);
1824 
1825 	/*
1826 	 * Number of entries in the final unit directory:
1827 	 *  - all of those in the template
1828 	 *  - management_agent
1829 	 *  - unit_characteristics
1830 	 *  - reconnect_timeout
1831 	 *  - unit unique ID
1832 	 *  - one for each LUN
1833 	 *
1834 	 *  MUST NOT include leaf or sub-directory entries
1835 	 */
1836 	num_entries = ARRAY_SIZE(sbp_unit_directory_template) + 4 + num_luns;
1837 
1838 	if (tport->directory_id != -1)
1839 		num_entries++;
1840 
1841 	/* allocate num_entries + 4 for the header and unique ID leaf */
1842 	data = kcalloc((num_entries + 4), sizeof(u32), GFP_KERNEL);
1843 	if (!data)
1844 		return -ENOMEM;
1845 
1846 	/* directory_length */
1847 	data[idx++] = num_entries << 16;
1848 
1849 	/* directory_id */
1850 	if (tport->directory_id != -1)
1851 		data[idx++] = (CSR_DIRECTORY_ID << 24) | tport->directory_id;
1852 
1853 	/* unit directory template */
1854 	memcpy(&data[idx], sbp_unit_directory_template,
1855 			sizeof(sbp_unit_directory_template));
1856 	idx += ARRAY_SIZE(sbp_unit_directory_template);
1857 
1858 	/* management_agent */
1859 	mgt_agt_addr = (tport->mgt_agt->handler.offset - CSR_REGISTER_BASE) / 4;
1860 	data[idx++] = 0x54000000 | (mgt_agt_addr & 0x00ffffff);
1861 
1862 	/* unit_characteristics */
1863 	data[idx++] = 0x3a000000 |
1864 		(((tport->mgt_orb_timeout * 2) << 8) & 0xff00) |
1865 		SBP_ORB_FETCH_SIZE;
1866 
1867 	/* reconnect_timeout */
1868 	data[idx++] = 0x3d000000 | (tport->max_reconnect_timeout & 0xffff);
1869 
1870 	/* unit unique ID (leaf is just after LUNs) */
1871 	data[idx++] = 0x8d000000 | (num_luns + 1);
1872 
1873 	rcu_read_lock();
1874 	hlist_for_each_entry_rcu(lun, &tport->tpg->se_tpg.tpg_lun_hlist, link) {
1875 		struct se_device *dev;
1876 		int type;
1877 		/*
1878 		 * rcu_dereference_raw protected by se_lun->lun_group symlink
1879 		 * reference to se_device->dev_group.
1880 		 */
1881 		dev = rcu_dereference_raw(lun->lun_se_dev);
1882 		type = dev->transport->get_device_type(dev);
1883 
1884 		/* logical_unit_number */
1885 		data[idx++] = 0x14000000 |
1886 			((type << 16) & 0x1f0000) |
1887 			(lun->unpacked_lun & 0xffff);
1888 	}
1889 	rcu_read_unlock();
1890 
1891 	/* unit unique ID leaf */
1892 	data[idx++] = 2 << 16;
1893 	data[idx++] = tport->guid >> 32;
1894 	data[idx++] = tport->guid;
1895 
1896 	tport->unit_directory.length = idx;
1897 	tport->unit_directory.key = (CSR_DIRECTORY | CSR_UNIT) << 24;
1898 	tport->unit_directory.data = data;
1899 
1900 	ret = fw_core_add_descriptor(&tport->unit_directory);
1901 	if (ret < 0) {
1902 		kfree(tport->unit_directory.data);
1903 		tport->unit_directory.data = NULL;
1904 	}
1905 
1906 	return ret;
1907 }
1908 
1909 static ssize_t sbp_parse_wwn(const char *name, u64 *wwn)
1910 {
1911 	const char *cp;
1912 	char c, nibble;
1913 	int pos = 0, err;
1914 
1915 	*wwn = 0;
1916 	for (cp = name; cp < &name[SBP_NAMELEN - 1]; cp++) {
1917 		c = *cp;
1918 		if (c == '\n' && cp[1] == '\0')
1919 			continue;
1920 		if (c == '\0') {
1921 			err = 2;
1922 			if (pos != 16)
1923 				goto fail;
1924 			return cp - name;
1925 		}
1926 		err = 3;
1927 		if (isdigit(c))
1928 			nibble = c - '0';
1929 		else if (isxdigit(c))
1930 			nibble = tolower(c) - 'a' + 10;
1931 		else
1932 			goto fail;
1933 		*wwn = (*wwn << 4) | nibble;
1934 		pos++;
1935 	}
1936 	err = 4;
1937 fail:
1938 	printk(KERN_INFO "err %u len %zu pos %u\n",
1939 			err, cp - name, pos);
1940 	return -1;
1941 }
1942 
1943 static ssize_t sbp_format_wwn(char *buf, size_t len, u64 wwn)
1944 {
1945 	return snprintf(buf, len, "%016llx", wwn);
1946 }
1947 
1948 static int sbp_init_nodeacl(struct se_node_acl *se_nacl, const char *name)
1949 {
1950 	u64 guid = 0;
1951 
1952 	if (sbp_parse_wwn(name, &guid) < 0)
1953 		return -EINVAL;
1954 	return 0;
1955 }
1956 
1957 static int sbp_post_link_lun(
1958 		struct se_portal_group *se_tpg,
1959 		struct se_lun *se_lun)
1960 {
1961 	struct sbp_tpg *tpg = container_of(se_tpg, struct sbp_tpg, se_tpg);
1962 
1963 	return sbp_update_unit_directory(tpg->tport);
1964 }
1965 
1966 static void sbp_pre_unlink_lun(
1967 		struct se_portal_group *se_tpg,
1968 		struct se_lun *se_lun)
1969 {
1970 	struct sbp_tpg *tpg = container_of(se_tpg, struct sbp_tpg, se_tpg);
1971 	struct sbp_tport *tport = tpg->tport;
1972 	int ret;
1973 
1974 	if (sbp_count_se_tpg_luns(&tpg->se_tpg) == 0)
1975 		tport->enable = 0;
1976 
1977 	ret = sbp_update_unit_directory(tport);
1978 	if (ret < 0)
1979 		pr_err("unlink LUN: failed to update unit directory\n");
1980 }
1981 
1982 static struct se_portal_group *sbp_make_tpg(struct se_wwn *wwn,
1983 					    const char *name)
1984 {
1985 	struct sbp_tport *tport =
1986 		container_of(wwn, struct sbp_tport, tport_wwn);
1987 
1988 	struct sbp_tpg *tpg;
1989 	unsigned long tpgt;
1990 	int ret;
1991 
1992 	if (strstr(name, "tpgt_") != name)
1993 		return ERR_PTR(-EINVAL);
1994 	if (kstrtoul(name + 5, 10, &tpgt) || tpgt > UINT_MAX)
1995 		return ERR_PTR(-EINVAL);
1996 
1997 	if (tport->tpg) {
1998 		pr_err("Only one TPG per Unit is possible.\n");
1999 		return ERR_PTR(-EBUSY);
2000 	}
2001 
2002 	tpg = kzalloc(sizeof(*tpg), GFP_KERNEL);
2003 	if (!tpg)
2004 		return ERR_PTR(-ENOMEM);
2005 
2006 	tpg->tport = tport;
2007 	tpg->tport_tpgt = tpgt;
2008 	tport->tpg = tpg;
2009 
2010 	/* default attribute values */
2011 	tport->enable = 0;
2012 	tport->directory_id = -1;
2013 	tport->mgt_orb_timeout = 15;
2014 	tport->max_reconnect_timeout = 5;
2015 	tport->max_logins_per_lun = 1;
2016 
2017 	tport->mgt_agt = sbp_management_agent_register(tport);
2018 	if (IS_ERR(tport->mgt_agt)) {
2019 		ret = PTR_ERR(tport->mgt_agt);
2020 		goto out_free_tpg;
2021 	}
2022 
2023 	ret = core_tpg_register(wwn, &tpg->se_tpg, SCSI_PROTOCOL_SBP);
2024 	if (ret < 0)
2025 		goto out_unreg_mgt_agt;
2026 
2027 	return &tpg->se_tpg;
2028 
2029 out_unreg_mgt_agt:
2030 	sbp_management_agent_unregister(tport->mgt_agt);
2031 out_free_tpg:
2032 	tport->tpg = NULL;
2033 	kfree(tpg);
2034 	return ERR_PTR(ret);
2035 }
2036 
2037 static void sbp_drop_tpg(struct se_portal_group *se_tpg)
2038 {
2039 	struct sbp_tpg *tpg = container_of(se_tpg, struct sbp_tpg, se_tpg);
2040 	struct sbp_tport *tport = tpg->tport;
2041 
2042 	core_tpg_deregister(se_tpg);
2043 	sbp_management_agent_unregister(tport->mgt_agt);
2044 	tport->tpg = NULL;
2045 	kfree(tpg);
2046 }
2047 
2048 static struct se_wwn *sbp_make_tport(
2049 		struct target_fabric_configfs *tf,
2050 		struct config_group *group,
2051 		const char *name)
2052 {
2053 	struct sbp_tport *tport;
2054 	u64 guid = 0;
2055 
2056 	if (sbp_parse_wwn(name, &guid) < 0)
2057 		return ERR_PTR(-EINVAL);
2058 
2059 	tport = kzalloc(sizeof(*tport), GFP_KERNEL);
2060 	if (!tport)
2061 		return ERR_PTR(-ENOMEM);
2062 
2063 	tport->guid = guid;
2064 	sbp_format_wwn(tport->tport_name, SBP_NAMELEN, guid);
2065 
2066 	return &tport->tport_wwn;
2067 }
2068 
2069 static void sbp_drop_tport(struct se_wwn *wwn)
2070 {
2071 	struct sbp_tport *tport =
2072 		container_of(wwn, struct sbp_tport, tport_wwn);
2073 
2074 	kfree(tport);
2075 }
2076 
2077 static ssize_t sbp_wwn_version_show(struct config_item *item, char *page)
2078 {
2079 	return sprintf(page, "FireWire SBP fabric module %s\n", SBP_VERSION);
2080 }
2081 
2082 CONFIGFS_ATTR_RO(sbp_wwn_, version);
2083 
2084 static struct configfs_attribute *sbp_wwn_attrs[] = {
2085 	&sbp_wwn_attr_version,
2086 	NULL,
2087 };
2088 
2089 static ssize_t sbp_tpg_directory_id_show(struct config_item *item, char *page)
2090 {
2091 	struct se_portal_group *se_tpg = to_tpg(item);
2092 	struct sbp_tpg *tpg = container_of(se_tpg, struct sbp_tpg, se_tpg);
2093 	struct sbp_tport *tport = tpg->tport;
2094 
2095 	if (tport->directory_id == -1)
2096 		return sprintf(page, "implicit\n");
2097 	else
2098 		return sprintf(page, "%06x\n", tport->directory_id);
2099 }
2100 
2101 static ssize_t sbp_tpg_directory_id_store(struct config_item *item,
2102 		const char *page, size_t count)
2103 {
2104 	struct se_portal_group *se_tpg = to_tpg(item);
2105 	struct sbp_tpg *tpg = container_of(se_tpg, struct sbp_tpg, se_tpg);
2106 	struct sbp_tport *tport = tpg->tport;
2107 	unsigned long val;
2108 
2109 	if (tport->enable) {
2110 		pr_err("Cannot change the directory_id on an active target.\n");
2111 		return -EBUSY;
2112 	}
2113 
2114 	if (strstr(page, "implicit") == page) {
2115 		tport->directory_id = -1;
2116 	} else {
2117 		if (kstrtoul(page, 16, &val) < 0)
2118 			return -EINVAL;
2119 		if (val > 0xffffff)
2120 			return -EINVAL;
2121 
2122 		tport->directory_id = val;
2123 	}
2124 
2125 	return count;
2126 }
2127 
2128 static int sbp_enable_tpg(struct se_portal_group *se_tpg, bool enable)
2129 {
2130 	struct sbp_tpg *tpg = container_of(se_tpg, struct sbp_tpg, se_tpg);
2131 	struct sbp_tport *tport = tpg->tport;
2132 	int ret;
2133 
2134 	if (enable) {
2135 		if (sbp_count_se_tpg_luns(&tpg->se_tpg) == 0) {
2136 			pr_err("Cannot enable a target with no LUNs!\n");
2137 			return -EINVAL;
2138 		}
2139 	} else {
2140 		/* XXX: force-shutdown sessions instead? */
2141 		spin_lock_bh(&se_tpg->session_lock);
2142 		if (!list_empty(&se_tpg->tpg_sess_list)) {
2143 			spin_unlock_bh(&se_tpg->session_lock);
2144 			return -EBUSY;
2145 		}
2146 		spin_unlock_bh(&se_tpg->session_lock);
2147 	}
2148 
2149 	tport->enable = enable;
2150 
2151 	ret = sbp_update_unit_directory(tport);
2152 	if (ret < 0) {
2153 		pr_err("Could not update Config ROM\n");
2154 		return ret;
2155 	}
2156 
2157 	return 0;
2158 }
2159 
2160 CONFIGFS_ATTR(sbp_tpg_, directory_id);
2161 
2162 static struct configfs_attribute *sbp_tpg_base_attrs[] = {
2163 	&sbp_tpg_attr_directory_id,
2164 	NULL,
2165 };
2166 
2167 static ssize_t sbp_tpg_attrib_mgt_orb_timeout_show(struct config_item *item,
2168 		char *page)
2169 {
2170 	struct se_portal_group *se_tpg = attrib_to_tpg(item);
2171 	struct sbp_tpg *tpg = container_of(se_tpg, struct sbp_tpg, se_tpg);
2172 	struct sbp_tport *tport = tpg->tport;
2173 	return sprintf(page, "%d\n", tport->mgt_orb_timeout);
2174 }
2175 
2176 static ssize_t sbp_tpg_attrib_mgt_orb_timeout_store(struct config_item *item,
2177 		const char *page, size_t count)
2178 {
2179 	struct se_portal_group *se_tpg = attrib_to_tpg(item);
2180 	struct sbp_tpg *tpg = container_of(se_tpg, struct sbp_tpg, se_tpg);
2181 	struct sbp_tport *tport = tpg->tport;
2182 	unsigned long val;
2183 	int ret;
2184 
2185 	if (kstrtoul(page, 0, &val) < 0)
2186 		return -EINVAL;
2187 	if ((val < 1) || (val > 127))
2188 		return -EINVAL;
2189 
2190 	if (tport->mgt_orb_timeout == val)
2191 		return count;
2192 
2193 	tport->mgt_orb_timeout = val;
2194 
2195 	ret = sbp_update_unit_directory(tport);
2196 	if (ret < 0)
2197 		return ret;
2198 
2199 	return count;
2200 }
2201 
2202 static ssize_t sbp_tpg_attrib_max_reconnect_timeout_show(struct config_item *item,
2203 		char *page)
2204 {
2205 	struct se_portal_group *se_tpg = attrib_to_tpg(item);
2206 	struct sbp_tpg *tpg = container_of(se_tpg, struct sbp_tpg, se_tpg);
2207 	struct sbp_tport *tport = tpg->tport;
2208 	return sprintf(page, "%d\n", tport->max_reconnect_timeout);
2209 }
2210 
2211 static ssize_t sbp_tpg_attrib_max_reconnect_timeout_store(struct config_item *item,
2212 		const char *page, size_t count)
2213 {
2214 	struct se_portal_group *se_tpg = attrib_to_tpg(item);
2215 	struct sbp_tpg *tpg = container_of(se_tpg, struct sbp_tpg, se_tpg);
2216 	struct sbp_tport *tport = tpg->tport;
2217 	unsigned long val;
2218 	int ret;
2219 
2220 	if (kstrtoul(page, 0, &val) < 0)
2221 		return -EINVAL;
2222 	if ((val < 1) || (val > 32767))
2223 		return -EINVAL;
2224 
2225 	if (tport->max_reconnect_timeout == val)
2226 		return count;
2227 
2228 	tport->max_reconnect_timeout = val;
2229 
2230 	ret = sbp_update_unit_directory(tport);
2231 	if (ret < 0)
2232 		return ret;
2233 
2234 	return count;
2235 }
2236 
2237 static ssize_t sbp_tpg_attrib_max_logins_per_lun_show(struct config_item *item,
2238 		char *page)
2239 {
2240 	struct se_portal_group *se_tpg = attrib_to_tpg(item);
2241 	struct sbp_tpg *tpg = container_of(se_tpg, struct sbp_tpg, se_tpg);
2242 	struct sbp_tport *tport = tpg->tport;
2243 	return sprintf(page, "%d\n", tport->max_logins_per_lun);
2244 }
2245 
2246 static ssize_t sbp_tpg_attrib_max_logins_per_lun_store(struct config_item *item,
2247 		const char *page, size_t count)
2248 {
2249 	struct se_portal_group *se_tpg = attrib_to_tpg(item);
2250 	struct sbp_tpg *tpg = container_of(se_tpg, struct sbp_tpg, se_tpg);
2251 	struct sbp_tport *tport = tpg->tport;
2252 	unsigned long val;
2253 
2254 	if (kstrtoul(page, 0, &val) < 0)
2255 		return -EINVAL;
2256 	if ((val < 1) || (val > 127))
2257 		return -EINVAL;
2258 
2259 	/* XXX: also check against current count? */
2260 
2261 	tport->max_logins_per_lun = val;
2262 
2263 	return count;
2264 }
2265 
2266 CONFIGFS_ATTR(sbp_tpg_attrib_, mgt_orb_timeout);
2267 CONFIGFS_ATTR(sbp_tpg_attrib_, max_reconnect_timeout);
2268 CONFIGFS_ATTR(sbp_tpg_attrib_, max_logins_per_lun);
2269 
2270 static struct configfs_attribute *sbp_tpg_attrib_attrs[] = {
2271 	&sbp_tpg_attrib_attr_mgt_orb_timeout,
2272 	&sbp_tpg_attrib_attr_max_reconnect_timeout,
2273 	&sbp_tpg_attrib_attr_max_logins_per_lun,
2274 	NULL,
2275 };
2276 
2277 static const struct target_core_fabric_ops sbp_ops = {
2278 	.module				= THIS_MODULE,
2279 	.fabric_name			= "sbp",
2280 	.tpg_get_wwn			= sbp_get_fabric_wwn,
2281 	.tpg_get_tag			= sbp_get_tag,
2282 	.tpg_check_demo_mode		= sbp_check_true,
2283 	.tpg_check_demo_mode_cache	= sbp_check_true,
2284 	.tpg_check_demo_mode_write_protect = sbp_check_false,
2285 	.tpg_check_prod_mode_write_protect = sbp_check_false,
2286 	.tpg_get_inst_index		= sbp_tpg_get_inst_index,
2287 	.release_cmd			= sbp_release_cmd,
2288 	.sess_get_index			= sbp_sess_get_index,
2289 	.write_pending			= sbp_write_pending,
2290 	.set_default_node_attributes	= sbp_set_default_node_attrs,
2291 	.get_cmd_state			= sbp_get_cmd_state,
2292 	.queue_data_in			= sbp_queue_data_in,
2293 	.queue_status			= sbp_queue_status,
2294 	.queue_tm_rsp			= sbp_queue_tm_rsp,
2295 	.aborted_task			= sbp_aborted_task,
2296 	.check_stop_free		= sbp_check_stop_free,
2297 
2298 	.fabric_make_wwn		= sbp_make_tport,
2299 	.fabric_drop_wwn		= sbp_drop_tport,
2300 	.fabric_make_tpg		= sbp_make_tpg,
2301 	.fabric_enable_tpg		= sbp_enable_tpg,
2302 	.fabric_drop_tpg		= sbp_drop_tpg,
2303 	.fabric_post_link		= sbp_post_link_lun,
2304 	.fabric_pre_unlink		= sbp_pre_unlink_lun,
2305 	.fabric_make_np			= NULL,
2306 	.fabric_drop_np			= NULL,
2307 	.fabric_init_nodeacl		= sbp_init_nodeacl,
2308 
2309 	.tfc_wwn_attrs			= sbp_wwn_attrs,
2310 	.tfc_tpg_base_attrs		= sbp_tpg_base_attrs,
2311 	.tfc_tpg_attrib_attrs		= sbp_tpg_attrib_attrs,
2312 };
2313 
2314 static int __init sbp_init(void)
2315 {
2316 	return target_register_template(&sbp_ops);
2317 };
2318 
2319 static void __exit sbp_exit(void)
2320 {
2321 	target_unregister_template(&sbp_ops);
2322 };
2323 
2324 MODULE_DESCRIPTION("FireWire SBP fabric driver");
2325 MODULE_LICENSE("GPL");
2326 module_init(sbp_init);
2327 module_exit(sbp_exit);
2328