xref: /openbmc/linux/drivers/target/sbp/sbp_target.c (revision 82e6fdd6)
1 /*
2  * SBP2 target driver (SCSI over IEEE1394 in target mode)
3  *
4  * Copyright (C) 2011  Chris Boot <bootc@bootc.net>
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; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software Foundation,
18  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19  */
20 
21 #define KMSG_COMPONENT "sbp_target"
22 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
23 
24 #include <linux/kernel.h>
25 #include <linux/module.h>
26 #include <linux/init.h>
27 #include <linux/types.h>
28 #include <linux/string.h>
29 #include <linux/configfs.h>
30 #include <linux/ctype.h>
31 #include <linux/delay.h>
32 #include <linux/firewire.h>
33 #include <linux/firewire-constants.h>
34 #include <scsi/scsi_proto.h>
35 #include <scsi/scsi_tcq.h>
36 #include <target/target_core_base.h>
37 #include <target/target_core_backend.h>
38 #include <target/target_core_fabric.h>
39 #include <asm/unaligned.h>
40 
41 #include "sbp_target.h"
42 
43 /* FireWire address region for management and command block address handlers */
44 static const struct fw_address_region sbp_register_region = {
45 	.start	= CSR_REGISTER_BASE + 0x10000,
46 	.end	= 0x1000000000000ULL,
47 };
48 
49 static const u32 sbp_unit_directory_template[] = {
50 	0x1200609e, /* unit_specifier_id: NCITS/T10 */
51 	0x13010483, /* unit_sw_version: 1155D Rev 4 */
52 	0x3800609e, /* command_set_specifier_id: NCITS/T10 */
53 	0x390104d8, /* command_set: SPC-2 */
54 	0x3b000000, /* command_set_revision: 0 */
55 	0x3c000001, /* firmware_revision: 1 */
56 };
57 
58 #define SESSION_MAINTENANCE_INTERVAL HZ
59 
60 static atomic_t login_id = ATOMIC_INIT(0);
61 
62 static void session_maintenance_work(struct work_struct *);
63 static int sbp_run_transaction(struct fw_card *, int, int, int, int,
64 		unsigned long long, void *, size_t);
65 
66 static int read_peer_guid(u64 *guid, const struct sbp_management_request *req)
67 {
68 	int ret;
69 	__be32 high, low;
70 
71 	ret = sbp_run_transaction(req->card, TCODE_READ_QUADLET_REQUEST,
72 			req->node_addr, req->generation, req->speed,
73 			(CSR_REGISTER_BASE | CSR_CONFIG_ROM) + 3 * 4,
74 			&high, sizeof(high));
75 	if (ret != RCODE_COMPLETE)
76 		return ret;
77 
78 	ret = sbp_run_transaction(req->card, TCODE_READ_QUADLET_REQUEST,
79 			req->node_addr, req->generation, req->speed,
80 			(CSR_REGISTER_BASE | CSR_CONFIG_ROM) + 4 * 4,
81 			&low, sizeof(low));
82 	if (ret != RCODE_COMPLETE)
83 		return ret;
84 
85 	*guid = (u64)be32_to_cpu(high) << 32 | be32_to_cpu(low);
86 
87 	return RCODE_COMPLETE;
88 }
89 
90 static struct sbp_session *sbp_session_find_by_guid(
91 	struct sbp_tpg *tpg, u64 guid)
92 {
93 	struct se_session *se_sess;
94 	struct sbp_session *sess, *found = NULL;
95 
96 	spin_lock_bh(&tpg->se_tpg.session_lock);
97 	list_for_each_entry(se_sess, &tpg->se_tpg.tpg_sess_list, sess_list) {
98 		sess = se_sess->fabric_sess_ptr;
99 		if (sess->guid == guid)
100 			found = sess;
101 	}
102 	spin_unlock_bh(&tpg->se_tpg.session_lock);
103 
104 	return found;
105 }
106 
107 static struct sbp_login_descriptor *sbp_login_find_by_lun(
108 		struct sbp_session *session, u32 unpacked_lun)
109 {
110 	struct sbp_login_descriptor *login, *found = NULL;
111 
112 	spin_lock_bh(&session->lock);
113 	list_for_each_entry(login, &session->login_list, link) {
114 		if (login->login_lun == unpacked_lun)
115 			found = login;
116 	}
117 	spin_unlock_bh(&session->lock);
118 
119 	return found;
120 }
121 
122 static int sbp_login_count_all_by_lun(
123 		struct sbp_tpg *tpg,
124 		u32 unpacked_lun,
125 		int exclusive)
126 {
127 	struct se_session *se_sess;
128 	struct sbp_session *sess;
129 	struct sbp_login_descriptor *login;
130 	int count = 0;
131 
132 	spin_lock_bh(&tpg->se_tpg.session_lock);
133 	list_for_each_entry(se_sess, &tpg->se_tpg.tpg_sess_list, sess_list) {
134 		sess = se_sess->fabric_sess_ptr;
135 
136 		spin_lock_bh(&sess->lock);
137 		list_for_each_entry(login, &sess->login_list, link) {
138 			if (login->login_lun != unpacked_lun)
139 				continue;
140 
141 			if (!exclusive || login->exclusive)
142 				count++;
143 		}
144 		spin_unlock_bh(&sess->lock);
145 	}
146 	spin_unlock_bh(&tpg->se_tpg.session_lock);
147 
148 	return count;
149 }
150 
151 static struct sbp_login_descriptor *sbp_login_find_by_id(
152 	struct sbp_tpg *tpg, int login_id)
153 {
154 	struct se_session *se_sess;
155 	struct sbp_session *sess;
156 	struct sbp_login_descriptor *login, *found = NULL;
157 
158 	spin_lock_bh(&tpg->se_tpg.session_lock);
159 	list_for_each_entry(se_sess, &tpg->se_tpg.tpg_sess_list, sess_list) {
160 		sess = se_sess->fabric_sess_ptr;
161 
162 		spin_lock_bh(&sess->lock);
163 		list_for_each_entry(login, &sess->login_list, link) {
164 			if (login->login_id == login_id)
165 				found = login;
166 		}
167 		spin_unlock_bh(&sess->lock);
168 	}
169 	spin_unlock_bh(&tpg->se_tpg.session_lock);
170 
171 	return found;
172 }
173 
174 static u32 sbp_get_lun_from_tpg(struct sbp_tpg *tpg, u32 login_lun, int *err)
175 {
176 	struct se_portal_group *se_tpg = &tpg->se_tpg;
177 	struct se_lun *se_lun;
178 
179 	rcu_read_lock();
180 	hlist_for_each_entry_rcu(se_lun, &se_tpg->tpg_lun_hlist, link) {
181 		if (se_lun->unpacked_lun == login_lun) {
182 			rcu_read_unlock();
183 			*err = 0;
184 			return login_lun;
185 		}
186 	}
187 	rcu_read_unlock();
188 
189 	*err = -ENODEV;
190 	return login_lun;
191 }
192 
193 static struct sbp_session *sbp_session_create(
194 		struct sbp_tpg *tpg,
195 		u64 guid)
196 {
197 	struct sbp_session *sess;
198 	int ret;
199 	char guid_str[17];
200 
201 	snprintf(guid_str, sizeof(guid_str), "%016llx", guid);
202 
203 	sess = kmalloc(sizeof(*sess), GFP_KERNEL);
204 	if (!sess)
205 		return ERR_PTR(-ENOMEM);
206 
207 	spin_lock_init(&sess->lock);
208 	INIT_LIST_HEAD(&sess->login_list);
209 	INIT_DELAYED_WORK(&sess->maint_work, session_maintenance_work);
210 	sess->guid = guid;
211 
212 	sess->se_sess = target_alloc_session(&tpg->se_tpg, 128,
213 					     sizeof(struct sbp_target_request),
214 					     TARGET_PROT_NORMAL, guid_str,
215 					     sess, NULL);
216 	if (IS_ERR(sess->se_sess)) {
217 		pr_err("failed to init se_session\n");
218 		ret = PTR_ERR(sess->se_sess);
219 		kfree(sess);
220 		return ERR_PTR(ret);
221 	}
222 
223 	return sess;
224 }
225 
226 static void sbp_session_release(struct sbp_session *sess, bool cancel_work)
227 {
228 	spin_lock_bh(&sess->lock);
229 	if (!list_empty(&sess->login_list)) {
230 		spin_unlock_bh(&sess->lock);
231 		return;
232 	}
233 	spin_unlock_bh(&sess->lock);
234 
235 	if (cancel_work)
236 		cancel_delayed_work_sync(&sess->maint_work);
237 
238 	transport_deregister_session_configfs(sess->se_sess);
239 	transport_deregister_session(sess->se_sess);
240 
241 	if (sess->card)
242 		fw_card_put(sess->card);
243 
244 	kfree(sess);
245 }
246 
247 static void sbp_target_agent_unregister(struct sbp_target_agent *);
248 
249 static void sbp_login_release(struct sbp_login_descriptor *login,
250 	bool cancel_work)
251 {
252 	struct sbp_session *sess = login->sess;
253 
254 	/* FIXME: abort/wait on tasks */
255 
256 	sbp_target_agent_unregister(login->tgt_agt);
257 
258 	if (sess) {
259 		spin_lock_bh(&sess->lock);
260 		list_del(&login->link);
261 		spin_unlock_bh(&sess->lock);
262 
263 		sbp_session_release(sess, cancel_work);
264 	}
265 
266 	kfree(login);
267 }
268 
269 static struct sbp_target_agent *sbp_target_agent_register(
270 	struct sbp_login_descriptor *);
271 
272 static void sbp_management_request_login(
273 	struct sbp_management_agent *agent, struct sbp_management_request *req,
274 	int *status_data_size)
275 {
276 	struct sbp_tport *tport = agent->tport;
277 	struct sbp_tpg *tpg = tport->tpg;
278 	struct sbp_session *sess;
279 	struct sbp_login_descriptor *login;
280 	struct sbp_login_response_block *response;
281 	u64 guid;
282 	u32 unpacked_lun;
283 	int login_response_len, ret;
284 
285 	unpacked_lun = sbp_get_lun_from_tpg(tpg,
286 			LOGIN_ORB_LUN(be32_to_cpu(req->orb.misc)), &ret);
287 	if (ret) {
288 		pr_notice("login to unknown LUN: %d\n",
289 			LOGIN_ORB_LUN(be32_to_cpu(req->orb.misc)));
290 
291 		req->status.status = cpu_to_be32(
292 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
293 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_LUN_NOTSUPP));
294 		return;
295 	}
296 
297 	ret = read_peer_guid(&guid, req);
298 	if (ret != RCODE_COMPLETE) {
299 		pr_warn("failed to read peer GUID: %d\n", ret);
300 
301 		req->status.status = cpu_to_be32(
302 			STATUS_BLOCK_RESP(STATUS_RESP_TRANSPORT_FAILURE) |
303 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_UNSPECIFIED_ERROR));
304 		return;
305 	}
306 
307 	pr_notice("mgt_agent LOGIN to LUN %d from %016llx\n",
308 		unpacked_lun, guid);
309 
310 	sess = sbp_session_find_by_guid(tpg, guid);
311 	if (sess) {
312 		login = sbp_login_find_by_lun(sess, unpacked_lun);
313 		if (login) {
314 			pr_notice("initiator already logged-in\n");
315 
316 			/*
317 			 * SBP-2 R4 says we should return access denied, but
318 			 * that can confuse initiators. Instead we need to
319 			 * treat this like a reconnect, but send the login
320 			 * response block like a fresh login.
321 			 *
322 			 * This is required particularly in the case of Apple
323 			 * devices booting off the FireWire target, where
324 			 * the firmware has an active login to the target. When
325 			 * the OS takes control of the session it issues its own
326 			 * LOGIN rather than a RECONNECT. To avoid the machine
327 			 * waiting until the reconnect_hold expires, we can skip
328 			 * the ACCESS_DENIED errors to speed things up.
329 			 */
330 
331 			goto already_logged_in;
332 		}
333 	}
334 
335 	/*
336 	 * check exclusive bit in login request
337 	 * reject with access_denied if any logins present
338 	 */
339 	if (LOGIN_ORB_EXCLUSIVE(be32_to_cpu(req->orb.misc)) &&
340 			sbp_login_count_all_by_lun(tpg, unpacked_lun, 0)) {
341 		pr_warn("refusing exclusive login with other active logins\n");
342 
343 		req->status.status = cpu_to_be32(
344 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
345 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_ACCESS_DENIED));
346 		return;
347 	}
348 
349 	/*
350 	 * check exclusive bit in any existing login descriptor
351 	 * reject with access_denied if any exclusive logins present
352 	 */
353 	if (sbp_login_count_all_by_lun(tpg, unpacked_lun, 1)) {
354 		pr_warn("refusing login while another exclusive login present\n");
355 
356 		req->status.status = cpu_to_be32(
357 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
358 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_ACCESS_DENIED));
359 		return;
360 	}
361 
362 	/*
363 	 * check we haven't exceeded the number of allowed logins
364 	 * reject with resources_unavailable if we have
365 	 */
366 	if (sbp_login_count_all_by_lun(tpg, unpacked_lun, 0) >=
367 			tport->max_logins_per_lun) {
368 		pr_warn("max number of logins reached\n");
369 
370 		req->status.status = cpu_to_be32(
371 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
372 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_RESOURCES_UNAVAIL));
373 		return;
374 	}
375 
376 	if (!sess) {
377 		sess = sbp_session_create(tpg, guid);
378 		if (IS_ERR(sess)) {
379 			switch (PTR_ERR(sess)) {
380 			case -EPERM:
381 				ret = SBP_STATUS_ACCESS_DENIED;
382 				break;
383 			default:
384 				ret = SBP_STATUS_RESOURCES_UNAVAIL;
385 				break;
386 			}
387 
388 			req->status.status = cpu_to_be32(
389 				STATUS_BLOCK_RESP(
390 					STATUS_RESP_REQUEST_COMPLETE) |
391 				STATUS_BLOCK_SBP_STATUS(ret));
392 			return;
393 		}
394 
395 		sess->node_id = req->node_addr;
396 		sess->card = fw_card_get(req->card);
397 		sess->generation = req->generation;
398 		sess->speed = req->speed;
399 
400 		schedule_delayed_work(&sess->maint_work,
401 				SESSION_MAINTENANCE_INTERVAL);
402 	}
403 
404 	/* only take the latest reconnect_hold into account */
405 	sess->reconnect_hold = min(
406 		1 << LOGIN_ORB_RECONNECT(be32_to_cpu(req->orb.misc)),
407 		tport->max_reconnect_timeout) - 1;
408 
409 	login = kmalloc(sizeof(*login), GFP_KERNEL);
410 	if (!login) {
411 		pr_err("failed to allocate login descriptor\n");
412 
413 		sbp_session_release(sess, true);
414 
415 		req->status.status = cpu_to_be32(
416 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
417 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_RESOURCES_UNAVAIL));
418 		return;
419 	}
420 
421 	login->sess = sess;
422 	login->login_lun = unpacked_lun;
423 	login->status_fifo_addr = sbp2_pointer_to_addr(&req->orb.status_fifo);
424 	login->exclusive = LOGIN_ORB_EXCLUSIVE(be32_to_cpu(req->orb.misc));
425 	login->login_id = atomic_inc_return(&login_id);
426 
427 	login->tgt_agt = sbp_target_agent_register(login);
428 	if (IS_ERR(login->tgt_agt)) {
429 		ret = PTR_ERR(login->tgt_agt);
430 		pr_err("failed to map command block handler: %d\n", ret);
431 
432 		sbp_session_release(sess, true);
433 		kfree(login);
434 
435 		req->status.status = cpu_to_be32(
436 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
437 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_RESOURCES_UNAVAIL));
438 		return;
439 	}
440 
441 	spin_lock_bh(&sess->lock);
442 	list_add_tail(&login->link, &sess->login_list);
443 	spin_unlock_bh(&sess->lock);
444 
445 already_logged_in:
446 	response = kzalloc(sizeof(*response), GFP_KERNEL);
447 	if (!response) {
448 		pr_err("failed to allocate login response block\n");
449 
450 		sbp_login_release(login, true);
451 
452 		req->status.status = cpu_to_be32(
453 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
454 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_RESOURCES_UNAVAIL));
455 		return;
456 	}
457 
458 	login_response_len = clamp_val(
459 			LOGIN_ORB_RESPONSE_LENGTH(be32_to_cpu(req->orb.length)),
460 			12, sizeof(*response));
461 	response->misc = cpu_to_be32(
462 		((login_response_len & 0xffff) << 16) |
463 		(login->login_id & 0xffff));
464 	response->reconnect_hold = cpu_to_be32(sess->reconnect_hold & 0xffff);
465 	addr_to_sbp2_pointer(login->tgt_agt->handler.offset,
466 		&response->command_block_agent);
467 
468 	ret = sbp_run_transaction(sess->card, TCODE_WRITE_BLOCK_REQUEST,
469 		sess->node_id, sess->generation, sess->speed,
470 		sbp2_pointer_to_addr(&req->orb.ptr2), response,
471 		login_response_len);
472 	if (ret != RCODE_COMPLETE) {
473 		pr_debug("failed to write login response block: %x\n", ret);
474 
475 		kfree(response);
476 		sbp_login_release(login, true);
477 
478 		req->status.status = cpu_to_be32(
479 			STATUS_BLOCK_RESP(STATUS_RESP_TRANSPORT_FAILURE) |
480 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_UNSPECIFIED_ERROR));
481 		return;
482 	}
483 
484 	kfree(response);
485 
486 	req->status.status = cpu_to_be32(
487 		STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
488 		STATUS_BLOCK_SBP_STATUS(SBP_STATUS_OK));
489 }
490 
491 static void sbp_management_request_query_logins(
492 	struct sbp_management_agent *agent, struct sbp_management_request *req,
493 	int *status_data_size)
494 {
495 	pr_notice("QUERY LOGINS not implemented\n");
496 	/* FIXME: implement */
497 
498 	req->status.status = cpu_to_be32(
499 		STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
500 		STATUS_BLOCK_SBP_STATUS(SBP_STATUS_REQ_TYPE_NOTSUPP));
501 }
502 
503 static void sbp_management_request_reconnect(
504 	struct sbp_management_agent *agent, struct sbp_management_request *req,
505 	int *status_data_size)
506 {
507 	struct sbp_tport *tport = agent->tport;
508 	struct sbp_tpg *tpg = tport->tpg;
509 	int ret;
510 	u64 guid;
511 	struct sbp_login_descriptor *login;
512 
513 	ret = read_peer_guid(&guid, req);
514 	if (ret != RCODE_COMPLETE) {
515 		pr_warn("failed to read peer GUID: %d\n", ret);
516 
517 		req->status.status = cpu_to_be32(
518 			STATUS_BLOCK_RESP(STATUS_RESP_TRANSPORT_FAILURE) |
519 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_UNSPECIFIED_ERROR));
520 		return;
521 	}
522 
523 	pr_notice("mgt_agent RECONNECT from %016llx\n", guid);
524 
525 	login = sbp_login_find_by_id(tpg,
526 		RECONNECT_ORB_LOGIN_ID(be32_to_cpu(req->orb.misc)));
527 
528 	if (!login) {
529 		pr_err("mgt_agent RECONNECT unknown login ID\n");
530 
531 		req->status.status = cpu_to_be32(
532 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
533 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_ACCESS_DENIED));
534 		return;
535 	}
536 
537 	if (login->sess->guid != guid) {
538 		pr_err("mgt_agent RECONNECT login GUID doesn't match\n");
539 
540 		req->status.status = cpu_to_be32(
541 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
542 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_ACCESS_DENIED));
543 		return;
544 	}
545 
546 	spin_lock_bh(&login->sess->lock);
547 	if (login->sess->card)
548 		fw_card_put(login->sess->card);
549 
550 	/* update the node details */
551 	login->sess->generation = req->generation;
552 	login->sess->node_id = req->node_addr;
553 	login->sess->card = fw_card_get(req->card);
554 	login->sess->speed = req->speed;
555 	spin_unlock_bh(&login->sess->lock);
556 
557 	req->status.status = cpu_to_be32(
558 		STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
559 		STATUS_BLOCK_SBP_STATUS(SBP_STATUS_OK));
560 }
561 
562 static void sbp_management_request_logout(
563 	struct sbp_management_agent *agent, struct sbp_management_request *req,
564 	int *status_data_size)
565 {
566 	struct sbp_tport *tport = agent->tport;
567 	struct sbp_tpg *tpg = tport->tpg;
568 	int id;
569 	struct sbp_login_descriptor *login;
570 
571 	id = LOGOUT_ORB_LOGIN_ID(be32_to_cpu(req->orb.misc));
572 
573 	login = sbp_login_find_by_id(tpg, id);
574 	if (!login) {
575 		pr_warn("cannot find login: %d\n", id);
576 
577 		req->status.status = cpu_to_be32(
578 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
579 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_LOGIN_ID_UNKNOWN));
580 		return;
581 	}
582 
583 	pr_info("mgt_agent LOGOUT from LUN %d session %d\n",
584 		login->login_lun, login->login_id);
585 
586 	if (req->node_addr != login->sess->node_id) {
587 		pr_warn("logout from different node ID\n");
588 
589 		req->status.status = cpu_to_be32(
590 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
591 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_ACCESS_DENIED));
592 		return;
593 	}
594 
595 	sbp_login_release(login, true);
596 
597 	req->status.status = cpu_to_be32(
598 		STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
599 		STATUS_BLOCK_SBP_STATUS(SBP_STATUS_OK));
600 }
601 
602 static void session_check_for_reset(struct sbp_session *sess)
603 {
604 	bool card_valid = false;
605 
606 	spin_lock_bh(&sess->lock);
607 
608 	if (sess->card) {
609 		spin_lock_irq(&sess->card->lock);
610 		card_valid = (sess->card->local_node != NULL);
611 		spin_unlock_irq(&sess->card->lock);
612 
613 		if (!card_valid) {
614 			fw_card_put(sess->card);
615 			sess->card = NULL;
616 		}
617 	}
618 
619 	if (!card_valid || (sess->generation != sess->card->generation)) {
620 		pr_info("Waiting for reconnect from node: %016llx\n",
621 				sess->guid);
622 
623 		sess->node_id = -1;
624 		sess->reconnect_expires = get_jiffies_64() +
625 			((sess->reconnect_hold + 1) * HZ);
626 	}
627 
628 	spin_unlock_bh(&sess->lock);
629 }
630 
631 static void session_reconnect_expired(struct sbp_session *sess)
632 {
633 	struct sbp_login_descriptor *login, *temp;
634 	LIST_HEAD(login_list);
635 
636 	pr_info("Reconnect timer expired for node: %016llx\n", sess->guid);
637 
638 	spin_lock_bh(&sess->lock);
639 	list_for_each_entry_safe(login, temp, &sess->login_list, link) {
640 		login->sess = NULL;
641 		list_move_tail(&login->link, &login_list);
642 	}
643 	spin_unlock_bh(&sess->lock);
644 
645 	list_for_each_entry_safe(login, temp, &login_list, link) {
646 		list_del(&login->link);
647 		sbp_login_release(login, false);
648 	}
649 
650 	sbp_session_release(sess, false);
651 }
652 
653 static void session_maintenance_work(struct work_struct *work)
654 {
655 	struct sbp_session *sess = container_of(work, struct sbp_session,
656 			maint_work.work);
657 
658 	/* could be called while tearing down the session */
659 	spin_lock_bh(&sess->lock);
660 	if (list_empty(&sess->login_list)) {
661 		spin_unlock_bh(&sess->lock);
662 		return;
663 	}
664 	spin_unlock_bh(&sess->lock);
665 
666 	if (sess->node_id != -1) {
667 		/* check for bus reset and make node_id invalid */
668 		session_check_for_reset(sess);
669 
670 		schedule_delayed_work(&sess->maint_work,
671 				SESSION_MAINTENANCE_INTERVAL);
672 	} else if (!time_after64(get_jiffies_64(), sess->reconnect_expires)) {
673 		/* still waiting for reconnect */
674 		schedule_delayed_work(&sess->maint_work,
675 				SESSION_MAINTENANCE_INTERVAL);
676 	} else {
677 		/* reconnect timeout has expired */
678 		session_reconnect_expired(sess);
679 	}
680 }
681 
682 static int tgt_agent_rw_agent_state(struct fw_card *card, int tcode, void *data,
683 		struct sbp_target_agent *agent)
684 {
685 	int state;
686 
687 	switch (tcode) {
688 	case TCODE_READ_QUADLET_REQUEST:
689 		pr_debug("tgt_agent AGENT_STATE READ\n");
690 
691 		spin_lock_bh(&agent->lock);
692 		state = agent->state;
693 		spin_unlock_bh(&agent->lock);
694 
695 		*(__be32 *)data = cpu_to_be32(state);
696 
697 		return RCODE_COMPLETE;
698 
699 	case TCODE_WRITE_QUADLET_REQUEST:
700 		/* ignored */
701 		return RCODE_COMPLETE;
702 
703 	default:
704 		return RCODE_TYPE_ERROR;
705 	}
706 }
707 
708 static int tgt_agent_rw_agent_reset(struct fw_card *card, int tcode, void *data,
709 		struct sbp_target_agent *agent)
710 {
711 	switch (tcode) {
712 	case TCODE_WRITE_QUADLET_REQUEST:
713 		pr_debug("tgt_agent AGENT_RESET\n");
714 		spin_lock_bh(&agent->lock);
715 		agent->state = AGENT_STATE_RESET;
716 		spin_unlock_bh(&agent->lock);
717 		return RCODE_COMPLETE;
718 
719 	default:
720 		return RCODE_TYPE_ERROR;
721 	}
722 }
723 
724 static int tgt_agent_rw_orb_pointer(struct fw_card *card, int tcode, void *data,
725 		struct sbp_target_agent *agent)
726 {
727 	struct sbp2_pointer *ptr = data;
728 
729 	switch (tcode) {
730 	case TCODE_WRITE_BLOCK_REQUEST:
731 		spin_lock_bh(&agent->lock);
732 		if (agent->state != AGENT_STATE_SUSPENDED &&
733 				agent->state != AGENT_STATE_RESET) {
734 			spin_unlock_bh(&agent->lock);
735 			pr_notice("Ignoring ORB_POINTER write while active.\n");
736 			return RCODE_CONFLICT_ERROR;
737 		}
738 		agent->state = AGENT_STATE_ACTIVE;
739 		spin_unlock_bh(&agent->lock);
740 
741 		agent->orb_pointer = sbp2_pointer_to_addr(ptr);
742 		agent->doorbell = false;
743 
744 		pr_debug("tgt_agent ORB_POINTER write: 0x%llx\n",
745 				agent->orb_pointer);
746 
747 		queue_work(system_unbound_wq, &agent->work);
748 
749 		return RCODE_COMPLETE;
750 
751 	case TCODE_READ_BLOCK_REQUEST:
752 		pr_debug("tgt_agent ORB_POINTER READ\n");
753 		spin_lock_bh(&agent->lock);
754 		addr_to_sbp2_pointer(agent->orb_pointer, ptr);
755 		spin_unlock_bh(&agent->lock);
756 		return RCODE_COMPLETE;
757 
758 	default:
759 		return RCODE_TYPE_ERROR;
760 	}
761 }
762 
763 static int tgt_agent_rw_doorbell(struct fw_card *card, int tcode, void *data,
764 		struct sbp_target_agent *agent)
765 {
766 	switch (tcode) {
767 	case TCODE_WRITE_QUADLET_REQUEST:
768 		spin_lock_bh(&agent->lock);
769 		if (agent->state != AGENT_STATE_SUSPENDED) {
770 			spin_unlock_bh(&agent->lock);
771 			pr_debug("Ignoring DOORBELL while active.\n");
772 			return RCODE_CONFLICT_ERROR;
773 		}
774 		agent->state = AGENT_STATE_ACTIVE;
775 		spin_unlock_bh(&agent->lock);
776 
777 		agent->doorbell = true;
778 
779 		pr_debug("tgt_agent DOORBELL\n");
780 
781 		queue_work(system_unbound_wq, &agent->work);
782 
783 		return RCODE_COMPLETE;
784 
785 	case TCODE_READ_QUADLET_REQUEST:
786 		return RCODE_COMPLETE;
787 
788 	default:
789 		return RCODE_TYPE_ERROR;
790 	}
791 }
792 
793 static int tgt_agent_rw_unsolicited_status_enable(struct fw_card *card,
794 		int tcode, void *data, struct sbp_target_agent *agent)
795 {
796 	switch (tcode) {
797 	case TCODE_WRITE_QUADLET_REQUEST:
798 		pr_debug("tgt_agent UNSOLICITED_STATUS_ENABLE\n");
799 		/* ignored as we don't send unsolicited status */
800 		return RCODE_COMPLETE;
801 
802 	case TCODE_READ_QUADLET_REQUEST:
803 		return RCODE_COMPLETE;
804 
805 	default:
806 		return RCODE_TYPE_ERROR;
807 	}
808 }
809 
810 static void tgt_agent_rw(struct fw_card *card, struct fw_request *request,
811 		int tcode, int destination, int source, int generation,
812 		unsigned long long offset, void *data, size_t length,
813 		void *callback_data)
814 {
815 	struct sbp_target_agent *agent = callback_data;
816 	struct sbp_session *sess = agent->login->sess;
817 	int sess_gen, sess_node, rcode;
818 
819 	spin_lock_bh(&sess->lock);
820 	sess_gen = sess->generation;
821 	sess_node = sess->node_id;
822 	spin_unlock_bh(&sess->lock);
823 
824 	if (generation != sess_gen) {
825 		pr_notice("ignoring request with wrong generation\n");
826 		rcode = RCODE_TYPE_ERROR;
827 		goto out;
828 	}
829 
830 	if (source != sess_node) {
831 		pr_notice("ignoring request from foreign node (%x != %x)\n",
832 				source, sess_node);
833 		rcode = RCODE_TYPE_ERROR;
834 		goto out;
835 	}
836 
837 	/* turn offset into the offset from the start of the block */
838 	offset -= agent->handler.offset;
839 
840 	if (offset == 0x00 && length == 4) {
841 		/* AGENT_STATE */
842 		rcode = tgt_agent_rw_agent_state(card, tcode, data, agent);
843 	} else if (offset == 0x04 && length == 4) {
844 		/* AGENT_RESET */
845 		rcode = tgt_agent_rw_agent_reset(card, tcode, data, agent);
846 	} else if (offset == 0x08 && length == 8) {
847 		/* ORB_POINTER */
848 		rcode = tgt_agent_rw_orb_pointer(card, tcode, data, agent);
849 	} else if (offset == 0x10 && length == 4) {
850 		/* DOORBELL */
851 		rcode = tgt_agent_rw_doorbell(card, tcode, data, agent);
852 	} else if (offset == 0x14 && length == 4) {
853 		/* UNSOLICITED_STATUS_ENABLE */
854 		rcode = tgt_agent_rw_unsolicited_status_enable(card, tcode,
855 				data, agent);
856 	} else {
857 		rcode = RCODE_ADDRESS_ERROR;
858 	}
859 
860 out:
861 	fw_send_response(card, request, rcode);
862 }
863 
864 static void sbp_handle_command(struct sbp_target_request *);
865 static int sbp_send_status(struct sbp_target_request *);
866 static void sbp_free_request(struct sbp_target_request *);
867 
868 static void tgt_agent_process_work(struct work_struct *work)
869 {
870 	struct sbp_target_request *req =
871 		container_of(work, struct sbp_target_request, work);
872 
873 	pr_debug("tgt_orb ptr:0x%llx next_ORB:0x%llx data_descriptor:0x%llx misc:0x%x\n",
874 			req->orb_pointer,
875 			sbp2_pointer_to_addr(&req->orb.next_orb),
876 			sbp2_pointer_to_addr(&req->orb.data_descriptor),
877 			be32_to_cpu(req->orb.misc));
878 
879 	if (req->orb_pointer >> 32)
880 		pr_debug("ORB with high bits set\n");
881 
882 	switch (ORB_REQUEST_FORMAT(be32_to_cpu(req->orb.misc))) {
883 		case 0:/* Format specified by this standard */
884 			sbp_handle_command(req);
885 			return;
886 		case 1: /* Reserved for future standardization */
887 		case 2: /* Vendor-dependent */
888 			req->status.status |= cpu_to_be32(
889 					STATUS_BLOCK_RESP(
890 						STATUS_RESP_REQUEST_COMPLETE) |
891 					STATUS_BLOCK_DEAD(0) |
892 					STATUS_BLOCK_LEN(1) |
893 					STATUS_BLOCK_SBP_STATUS(
894 						SBP_STATUS_REQ_TYPE_NOTSUPP));
895 			sbp_send_status(req);
896 			return;
897 		case 3: /* Dummy ORB */
898 			req->status.status |= cpu_to_be32(
899 					STATUS_BLOCK_RESP(
900 						STATUS_RESP_REQUEST_COMPLETE) |
901 					STATUS_BLOCK_DEAD(0) |
902 					STATUS_BLOCK_LEN(1) |
903 					STATUS_BLOCK_SBP_STATUS(
904 						SBP_STATUS_DUMMY_ORB_COMPLETE));
905 			sbp_send_status(req);
906 			return;
907 		default:
908 			BUG();
909 	}
910 }
911 
912 /* used to double-check we haven't been issued an AGENT_RESET */
913 static inline bool tgt_agent_check_active(struct sbp_target_agent *agent)
914 {
915 	bool active;
916 
917 	spin_lock_bh(&agent->lock);
918 	active = (agent->state == AGENT_STATE_ACTIVE);
919 	spin_unlock_bh(&agent->lock);
920 
921 	return active;
922 }
923 
924 static struct sbp_target_request *sbp_mgt_get_req(struct sbp_session *sess,
925 	struct fw_card *card, u64 next_orb)
926 {
927 	struct se_session *se_sess = sess->se_sess;
928 	struct sbp_target_request *req;
929 	int tag;
930 
931 	tag = percpu_ida_alloc(&se_sess->sess_tag_pool, TASK_RUNNING);
932 	if (tag < 0)
933 		return ERR_PTR(-ENOMEM);
934 
935 	req = &((struct sbp_target_request *)se_sess->sess_cmd_map)[tag];
936 	memset(req, 0, sizeof(*req));
937 	req->se_cmd.map_tag = tag;
938 	req->se_cmd.tag = next_orb;
939 
940 	return req;
941 }
942 
943 static void tgt_agent_fetch_work(struct work_struct *work)
944 {
945 	struct sbp_target_agent *agent =
946 		container_of(work, struct sbp_target_agent, work);
947 	struct sbp_session *sess = agent->login->sess;
948 	struct sbp_target_request *req;
949 	int ret;
950 	bool doorbell = agent->doorbell;
951 	u64 next_orb = agent->orb_pointer;
952 
953 	while (next_orb && tgt_agent_check_active(agent)) {
954 		req = sbp_mgt_get_req(sess, sess->card, next_orb);
955 		if (IS_ERR(req)) {
956 			spin_lock_bh(&agent->lock);
957 			agent->state = AGENT_STATE_DEAD;
958 			spin_unlock_bh(&agent->lock);
959 			return;
960 		}
961 
962 		req->login = agent->login;
963 		req->orb_pointer = next_orb;
964 
965 		req->status.status = cpu_to_be32(STATUS_BLOCK_ORB_OFFSET_HIGH(
966 					req->orb_pointer >> 32));
967 		req->status.orb_low = cpu_to_be32(
968 				req->orb_pointer & 0xfffffffc);
969 
970 		/* read in the ORB */
971 		ret = sbp_run_transaction(sess->card, TCODE_READ_BLOCK_REQUEST,
972 				sess->node_id, sess->generation, sess->speed,
973 				req->orb_pointer, &req->orb, sizeof(req->orb));
974 		if (ret != RCODE_COMPLETE) {
975 			pr_debug("tgt_orb fetch failed: %x\n", ret);
976 			req->status.status |= cpu_to_be32(
977 					STATUS_BLOCK_SRC(
978 						STATUS_SRC_ORB_FINISHED) |
979 					STATUS_BLOCK_RESP(
980 						STATUS_RESP_TRANSPORT_FAILURE) |
981 					STATUS_BLOCK_DEAD(1) |
982 					STATUS_BLOCK_LEN(1) |
983 					STATUS_BLOCK_SBP_STATUS(
984 						SBP_STATUS_UNSPECIFIED_ERROR));
985 			spin_lock_bh(&agent->lock);
986 			agent->state = AGENT_STATE_DEAD;
987 			spin_unlock_bh(&agent->lock);
988 
989 			sbp_send_status(req);
990 			return;
991 		}
992 
993 		/* check the next_ORB field */
994 		if (be32_to_cpu(req->orb.next_orb.high) & 0x80000000) {
995 			next_orb = 0;
996 			req->status.status |= cpu_to_be32(STATUS_BLOCK_SRC(
997 						STATUS_SRC_ORB_FINISHED));
998 		} else {
999 			next_orb = sbp2_pointer_to_addr(&req->orb.next_orb);
1000 			req->status.status |= cpu_to_be32(STATUS_BLOCK_SRC(
1001 						STATUS_SRC_ORB_CONTINUING));
1002 		}
1003 
1004 		if (tgt_agent_check_active(agent) && !doorbell) {
1005 			INIT_WORK(&req->work, tgt_agent_process_work);
1006 			queue_work(system_unbound_wq, &req->work);
1007 		} else {
1008 			/* don't process this request, just check next_ORB */
1009 			sbp_free_request(req);
1010 		}
1011 
1012 		spin_lock_bh(&agent->lock);
1013 		doorbell = agent->doorbell = false;
1014 
1015 		/* check if we should carry on processing */
1016 		if (next_orb)
1017 			agent->orb_pointer = next_orb;
1018 		else
1019 			agent->state = AGENT_STATE_SUSPENDED;
1020 
1021 		spin_unlock_bh(&agent->lock);
1022 	};
1023 }
1024 
1025 static struct sbp_target_agent *sbp_target_agent_register(
1026 		struct sbp_login_descriptor *login)
1027 {
1028 	struct sbp_target_agent *agent;
1029 	int ret;
1030 
1031 	agent = kmalloc(sizeof(*agent), GFP_KERNEL);
1032 	if (!agent)
1033 		return ERR_PTR(-ENOMEM);
1034 
1035 	spin_lock_init(&agent->lock);
1036 
1037 	agent->handler.length = 0x20;
1038 	agent->handler.address_callback = tgt_agent_rw;
1039 	agent->handler.callback_data = agent;
1040 
1041 	agent->login = login;
1042 	agent->state = AGENT_STATE_RESET;
1043 	INIT_WORK(&agent->work, tgt_agent_fetch_work);
1044 	agent->orb_pointer = 0;
1045 	agent->doorbell = false;
1046 
1047 	ret = fw_core_add_address_handler(&agent->handler,
1048 			&sbp_register_region);
1049 	if (ret < 0) {
1050 		kfree(agent);
1051 		return ERR_PTR(ret);
1052 	}
1053 
1054 	return agent;
1055 }
1056 
1057 static void sbp_target_agent_unregister(struct sbp_target_agent *agent)
1058 {
1059 	fw_core_remove_address_handler(&agent->handler);
1060 	cancel_work_sync(&agent->work);
1061 	kfree(agent);
1062 }
1063 
1064 /*
1065  * Simple wrapper around fw_run_transaction that retries the transaction several
1066  * times in case of failure, with an exponential backoff.
1067  */
1068 static int sbp_run_transaction(struct fw_card *card, int tcode, int destination_id,
1069 		int generation, int speed, unsigned long long offset,
1070 		void *payload, size_t length)
1071 {
1072 	int attempt, ret, delay;
1073 
1074 	for (attempt = 1; attempt <= 5; attempt++) {
1075 		ret = fw_run_transaction(card, tcode, destination_id,
1076 				generation, speed, offset, payload, length);
1077 
1078 		switch (ret) {
1079 		case RCODE_COMPLETE:
1080 		case RCODE_TYPE_ERROR:
1081 		case RCODE_ADDRESS_ERROR:
1082 		case RCODE_GENERATION:
1083 			return ret;
1084 
1085 		default:
1086 			delay = 5 * attempt * attempt;
1087 			usleep_range(delay, delay * 2);
1088 		}
1089 	}
1090 
1091 	return ret;
1092 }
1093 
1094 /*
1095  * Wrapper around sbp_run_transaction that gets the card, destination,
1096  * generation and speed out of the request's session.
1097  */
1098 static int sbp_run_request_transaction(struct sbp_target_request *req,
1099 		int tcode, unsigned long long offset, void *payload,
1100 		size_t length)
1101 {
1102 	struct sbp_login_descriptor *login = req->login;
1103 	struct sbp_session *sess = login->sess;
1104 	struct fw_card *card;
1105 	int node_id, generation, speed, ret;
1106 
1107 	spin_lock_bh(&sess->lock);
1108 	card = fw_card_get(sess->card);
1109 	node_id = sess->node_id;
1110 	generation = sess->generation;
1111 	speed = sess->speed;
1112 	spin_unlock_bh(&sess->lock);
1113 
1114 	ret = sbp_run_transaction(card, tcode, node_id, generation, speed,
1115 			offset, payload, length);
1116 
1117 	fw_card_put(card);
1118 
1119 	return ret;
1120 }
1121 
1122 static int sbp_fetch_command(struct sbp_target_request *req)
1123 {
1124 	int ret, cmd_len, copy_len;
1125 
1126 	cmd_len = scsi_command_size(req->orb.command_block);
1127 
1128 	req->cmd_buf = kmalloc(cmd_len, GFP_KERNEL);
1129 	if (!req->cmd_buf)
1130 		return -ENOMEM;
1131 
1132 	memcpy(req->cmd_buf, req->orb.command_block,
1133 		min_t(int, cmd_len, sizeof(req->orb.command_block)));
1134 
1135 	if (cmd_len > sizeof(req->orb.command_block)) {
1136 		pr_debug("sbp_fetch_command: filling in long command\n");
1137 		copy_len = cmd_len - sizeof(req->orb.command_block);
1138 
1139 		ret = sbp_run_request_transaction(req,
1140 				TCODE_READ_BLOCK_REQUEST,
1141 				req->orb_pointer + sizeof(req->orb),
1142 				req->cmd_buf + sizeof(req->orb.command_block),
1143 				copy_len);
1144 		if (ret != RCODE_COMPLETE)
1145 			return -EIO;
1146 	}
1147 
1148 	return 0;
1149 }
1150 
1151 static int sbp_fetch_page_table(struct sbp_target_request *req)
1152 {
1153 	int pg_tbl_sz, ret;
1154 	struct sbp_page_table_entry *pg_tbl;
1155 
1156 	if (!CMDBLK_ORB_PG_TBL_PRESENT(be32_to_cpu(req->orb.misc)))
1157 		return 0;
1158 
1159 	pg_tbl_sz = CMDBLK_ORB_DATA_SIZE(be32_to_cpu(req->orb.misc)) *
1160 		sizeof(struct sbp_page_table_entry);
1161 
1162 	pg_tbl = kmalloc(pg_tbl_sz, GFP_KERNEL);
1163 	if (!pg_tbl)
1164 		return -ENOMEM;
1165 
1166 	ret = sbp_run_request_transaction(req, TCODE_READ_BLOCK_REQUEST,
1167 			sbp2_pointer_to_addr(&req->orb.data_descriptor),
1168 			pg_tbl, pg_tbl_sz);
1169 	if (ret != RCODE_COMPLETE) {
1170 		kfree(pg_tbl);
1171 		return -EIO;
1172 	}
1173 
1174 	req->pg_tbl = pg_tbl;
1175 	return 0;
1176 }
1177 
1178 static void sbp_calc_data_length_direction(struct sbp_target_request *req,
1179 	u32 *data_len, enum dma_data_direction *data_dir)
1180 {
1181 	int data_size, direction, idx;
1182 
1183 	data_size = CMDBLK_ORB_DATA_SIZE(be32_to_cpu(req->orb.misc));
1184 	direction = CMDBLK_ORB_DIRECTION(be32_to_cpu(req->orb.misc));
1185 
1186 	if (!data_size) {
1187 		*data_len = 0;
1188 		*data_dir = DMA_NONE;
1189 		return;
1190 	}
1191 
1192 	*data_dir = direction ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1193 
1194 	if (req->pg_tbl) {
1195 		*data_len = 0;
1196 		for (idx = 0; idx < data_size; idx++) {
1197 			*data_len += be16_to_cpu(
1198 					req->pg_tbl[idx].segment_length);
1199 		}
1200 	} else {
1201 		*data_len = data_size;
1202 	}
1203 }
1204 
1205 static void sbp_handle_command(struct sbp_target_request *req)
1206 {
1207 	struct sbp_login_descriptor *login = req->login;
1208 	struct sbp_session *sess = login->sess;
1209 	int ret, unpacked_lun;
1210 	u32 data_length;
1211 	enum dma_data_direction data_dir;
1212 
1213 	ret = sbp_fetch_command(req);
1214 	if (ret) {
1215 		pr_debug("sbp_handle_command: fetch command failed: %d\n", ret);
1216 		goto err;
1217 	}
1218 
1219 	ret = sbp_fetch_page_table(req);
1220 	if (ret) {
1221 		pr_debug("sbp_handle_command: fetch page table failed: %d\n",
1222 			ret);
1223 		goto err;
1224 	}
1225 
1226 	unpacked_lun = req->login->login_lun;
1227 	sbp_calc_data_length_direction(req, &data_length, &data_dir);
1228 
1229 	pr_debug("sbp_handle_command ORB:0x%llx unpacked_lun:%d data_len:%d data_dir:%d\n",
1230 			req->orb_pointer, unpacked_lun, data_length, data_dir);
1231 
1232 	/* only used for printk until we do TMRs */
1233 	req->se_cmd.tag = req->orb_pointer;
1234 	if (target_submit_cmd(&req->se_cmd, sess->se_sess, req->cmd_buf,
1235 			      req->sense_buf, unpacked_lun, data_length,
1236 			      TCM_SIMPLE_TAG, data_dir, TARGET_SCF_ACK_KREF))
1237 		goto err;
1238 
1239 	return;
1240 
1241 err:
1242 	req->status.status |= cpu_to_be32(
1243 		STATUS_BLOCK_RESP(STATUS_RESP_TRANSPORT_FAILURE) |
1244 		STATUS_BLOCK_DEAD(0) |
1245 		STATUS_BLOCK_LEN(1) |
1246 		STATUS_BLOCK_SBP_STATUS(SBP_STATUS_UNSPECIFIED_ERROR));
1247 	sbp_send_status(req);
1248 }
1249 
1250 /*
1251  * DMA_TO_DEVICE = read from initiator (SCSI WRITE)
1252  * DMA_FROM_DEVICE = write to initiator (SCSI READ)
1253  */
1254 static int sbp_rw_data(struct sbp_target_request *req)
1255 {
1256 	struct sbp_session *sess = req->login->sess;
1257 	int tcode, sg_miter_flags, max_payload, pg_size, speed, node_id,
1258 		generation, num_pte, length, tfr_length,
1259 		rcode = RCODE_COMPLETE;
1260 	struct sbp_page_table_entry *pte;
1261 	unsigned long long offset;
1262 	struct fw_card *card;
1263 	struct sg_mapping_iter iter;
1264 
1265 	if (req->se_cmd.data_direction == DMA_FROM_DEVICE) {
1266 		tcode = TCODE_WRITE_BLOCK_REQUEST;
1267 		sg_miter_flags = SG_MITER_FROM_SG;
1268 	} else {
1269 		tcode = TCODE_READ_BLOCK_REQUEST;
1270 		sg_miter_flags = SG_MITER_TO_SG;
1271 	}
1272 
1273 	max_payload = 4 << CMDBLK_ORB_MAX_PAYLOAD(be32_to_cpu(req->orb.misc));
1274 	speed = CMDBLK_ORB_SPEED(be32_to_cpu(req->orb.misc));
1275 
1276 	pg_size = CMDBLK_ORB_PG_SIZE(be32_to_cpu(req->orb.misc));
1277 	if (pg_size) {
1278 		pr_err("sbp_run_transaction: page size ignored\n");
1279 		pg_size = 0x100 << pg_size;
1280 	}
1281 
1282 	spin_lock_bh(&sess->lock);
1283 	card = fw_card_get(sess->card);
1284 	node_id = sess->node_id;
1285 	generation = sess->generation;
1286 	spin_unlock_bh(&sess->lock);
1287 
1288 	if (req->pg_tbl) {
1289 		pte = req->pg_tbl;
1290 		num_pte = CMDBLK_ORB_DATA_SIZE(be32_to_cpu(req->orb.misc));
1291 
1292 		offset = 0;
1293 		length = 0;
1294 	} else {
1295 		pte = NULL;
1296 		num_pte = 0;
1297 
1298 		offset = sbp2_pointer_to_addr(&req->orb.data_descriptor);
1299 		length = req->se_cmd.data_length;
1300 	}
1301 
1302 	sg_miter_start(&iter, req->se_cmd.t_data_sg, req->se_cmd.t_data_nents,
1303 		sg_miter_flags);
1304 
1305 	while (length || num_pte) {
1306 		if (!length) {
1307 			offset = (u64)be16_to_cpu(pte->segment_base_hi) << 32 |
1308 				be32_to_cpu(pte->segment_base_lo);
1309 			length = be16_to_cpu(pte->segment_length);
1310 
1311 			pte++;
1312 			num_pte--;
1313 		}
1314 
1315 		sg_miter_next(&iter);
1316 
1317 		tfr_length = min3(length, max_payload, (int)iter.length);
1318 
1319 		/* FIXME: take page_size into account */
1320 
1321 		rcode = sbp_run_transaction(card, tcode, node_id,
1322 				generation, speed,
1323 				offset, iter.addr, tfr_length);
1324 
1325 		if (rcode != RCODE_COMPLETE)
1326 			break;
1327 
1328 		length -= tfr_length;
1329 		offset += tfr_length;
1330 		iter.consumed = tfr_length;
1331 	}
1332 
1333 	sg_miter_stop(&iter);
1334 	fw_card_put(card);
1335 
1336 	if (rcode == RCODE_COMPLETE) {
1337 		WARN_ON(length != 0);
1338 		return 0;
1339 	} else {
1340 		return -EIO;
1341 	}
1342 }
1343 
1344 static int sbp_send_status(struct sbp_target_request *req)
1345 {
1346 	int rc, ret = 0, length;
1347 	struct sbp_login_descriptor *login = req->login;
1348 
1349 	length = (((be32_to_cpu(req->status.status) >> 24) & 0x07) + 1) * 4;
1350 
1351 	rc = sbp_run_request_transaction(req, TCODE_WRITE_BLOCK_REQUEST,
1352 			login->status_fifo_addr, &req->status, length);
1353 	if (rc != RCODE_COMPLETE) {
1354 		pr_debug("sbp_send_status: write failed: 0x%x\n", rc);
1355 		ret = -EIO;
1356 		goto put_ref;
1357 	}
1358 
1359 	pr_debug("sbp_send_status: status write complete for ORB: 0x%llx\n",
1360 			req->orb_pointer);
1361 	/*
1362 	 * Drop the extra ACK_KREF reference taken by target_submit_cmd()
1363 	 * ahead of sbp_check_stop_free() -> transport_generic_free_cmd()
1364 	 * final se_cmd->cmd_kref put.
1365 	 */
1366 put_ref:
1367 	target_put_sess_cmd(&req->se_cmd);
1368 	return ret;
1369 }
1370 
1371 static void sbp_sense_mangle(struct sbp_target_request *req)
1372 {
1373 	struct se_cmd *se_cmd = &req->se_cmd;
1374 	u8 *sense = req->sense_buf;
1375 	u8 *status = req->status.data;
1376 
1377 	WARN_ON(se_cmd->scsi_sense_length < 18);
1378 
1379 	switch (sense[0] & 0x7f) { 		/* sfmt */
1380 	case 0x70: /* current, fixed */
1381 		status[0] = 0 << 6;
1382 		break;
1383 	case 0x71: /* deferred, fixed */
1384 		status[0] = 1 << 6;
1385 		break;
1386 	case 0x72: /* current, descriptor */
1387 	case 0x73: /* deferred, descriptor */
1388 	default:
1389 		/*
1390 		 * TODO: SBP-3 specifies what we should do with descriptor
1391 		 * format sense data
1392 		 */
1393 		pr_err("sbp_send_sense: unknown sense format: 0x%x\n",
1394 			sense[0]);
1395 		req->status.status |= cpu_to_be32(
1396 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
1397 			STATUS_BLOCK_DEAD(0) |
1398 			STATUS_BLOCK_LEN(1) |
1399 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_REQUEST_ABORTED));
1400 		return;
1401 	}
1402 
1403 	status[0] |= se_cmd->scsi_status & 0x3f;/* status */
1404 	status[1] =
1405 		(sense[0] & 0x80) |		/* valid */
1406 		((sense[2] & 0xe0) >> 1) |	/* mark, eom, ili */
1407 		(sense[2] & 0x0f);		/* sense_key */
1408 	status[2] = se_cmd->scsi_asc;		/* sense_code */
1409 	status[3] = se_cmd->scsi_ascq;		/* sense_qualifier */
1410 
1411 	/* information */
1412 	status[4] = sense[3];
1413 	status[5] = sense[4];
1414 	status[6] = sense[5];
1415 	status[7] = sense[6];
1416 
1417 	/* CDB-dependent */
1418 	status[8] = sense[8];
1419 	status[9] = sense[9];
1420 	status[10] = sense[10];
1421 	status[11] = sense[11];
1422 
1423 	/* fru */
1424 	status[12] = sense[14];
1425 
1426 	/* sense_key-dependent */
1427 	status[13] = sense[15];
1428 	status[14] = sense[16];
1429 	status[15] = sense[17];
1430 
1431 	req->status.status |= cpu_to_be32(
1432 		STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
1433 		STATUS_BLOCK_DEAD(0) |
1434 		STATUS_BLOCK_LEN(5) |
1435 		STATUS_BLOCK_SBP_STATUS(SBP_STATUS_OK));
1436 }
1437 
1438 static int sbp_send_sense(struct sbp_target_request *req)
1439 {
1440 	struct se_cmd *se_cmd = &req->se_cmd;
1441 
1442 	if (se_cmd->scsi_sense_length) {
1443 		sbp_sense_mangle(req);
1444 	} else {
1445 		req->status.status |= cpu_to_be32(
1446 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
1447 			STATUS_BLOCK_DEAD(0) |
1448 			STATUS_BLOCK_LEN(1) |
1449 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_OK));
1450 	}
1451 
1452 	return sbp_send_status(req);
1453 }
1454 
1455 static void sbp_free_request(struct sbp_target_request *req)
1456 {
1457 	struct se_cmd *se_cmd = &req->se_cmd;
1458 	struct se_session *se_sess = se_cmd->se_sess;
1459 
1460 	kfree(req->pg_tbl);
1461 	kfree(req->cmd_buf);
1462 
1463 	percpu_ida_free(&se_sess->sess_tag_pool, se_cmd->map_tag);
1464 }
1465 
1466 static void sbp_mgt_agent_process(struct work_struct *work)
1467 {
1468 	struct sbp_management_agent *agent =
1469 		container_of(work, struct sbp_management_agent, work);
1470 	struct sbp_management_request *req = agent->request;
1471 	int ret;
1472 	int status_data_len = 0;
1473 
1474 	/* fetch the ORB from the initiator */
1475 	ret = sbp_run_transaction(req->card, TCODE_READ_BLOCK_REQUEST,
1476 		req->node_addr, req->generation, req->speed,
1477 		agent->orb_offset, &req->orb, sizeof(req->orb));
1478 	if (ret != RCODE_COMPLETE) {
1479 		pr_debug("mgt_orb fetch failed: %x\n", ret);
1480 		goto out;
1481 	}
1482 
1483 	pr_debug("mgt_orb ptr1:0x%llx ptr2:0x%llx misc:0x%x len:0x%x status_fifo:0x%llx\n",
1484 		sbp2_pointer_to_addr(&req->orb.ptr1),
1485 		sbp2_pointer_to_addr(&req->orb.ptr2),
1486 		be32_to_cpu(req->orb.misc), be32_to_cpu(req->orb.length),
1487 		sbp2_pointer_to_addr(&req->orb.status_fifo));
1488 
1489 	if (!ORB_NOTIFY(be32_to_cpu(req->orb.misc)) ||
1490 		ORB_REQUEST_FORMAT(be32_to_cpu(req->orb.misc)) != 0) {
1491 		pr_err("mgt_orb bad request\n");
1492 		goto out;
1493 	}
1494 
1495 	switch (MANAGEMENT_ORB_FUNCTION(be32_to_cpu(req->orb.misc))) {
1496 	case MANAGEMENT_ORB_FUNCTION_LOGIN:
1497 		sbp_management_request_login(agent, req, &status_data_len);
1498 		break;
1499 
1500 	case MANAGEMENT_ORB_FUNCTION_QUERY_LOGINS:
1501 		sbp_management_request_query_logins(agent, req,
1502 				&status_data_len);
1503 		break;
1504 
1505 	case MANAGEMENT_ORB_FUNCTION_RECONNECT:
1506 		sbp_management_request_reconnect(agent, req, &status_data_len);
1507 		break;
1508 
1509 	case MANAGEMENT_ORB_FUNCTION_SET_PASSWORD:
1510 		pr_notice("SET PASSWORD not implemented\n");
1511 
1512 		req->status.status = cpu_to_be32(
1513 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
1514 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_REQ_TYPE_NOTSUPP));
1515 
1516 		break;
1517 
1518 	case MANAGEMENT_ORB_FUNCTION_LOGOUT:
1519 		sbp_management_request_logout(agent, req, &status_data_len);
1520 		break;
1521 
1522 	case MANAGEMENT_ORB_FUNCTION_ABORT_TASK:
1523 		pr_notice("ABORT TASK not implemented\n");
1524 
1525 		req->status.status = cpu_to_be32(
1526 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
1527 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_REQ_TYPE_NOTSUPP));
1528 
1529 		break;
1530 
1531 	case MANAGEMENT_ORB_FUNCTION_ABORT_TASK_SET:
1532 		pr_notice("ABORT TASK SET not implemented\n");
1533 
1534 		req->status.status = cpu_to_be32(
1535 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
1536 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_REQ_TYPE_NOTSUPP));
1537 
1538 		break;
1539 
1540 	case MANAGEMENT_ORB_FUNCTION_LOGICAL_UNIT_RESET:
1541 		pr_notice("LOGICAL UNIT RESET not implemented\n");
1542 
1543 		req->status.status = cpu_to_be32(
1544 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
1545 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_REQ_TYPE_NOTSUPP));
1546 
1547 		break;
1548 
1549 	case MANAGEMENT_ORB_FUNCTION_TARGET_RESET:
1550 		pr_notice("TARGET RESET not implemented\n");
1551 
1552 		req->status.status = cpu_to_be32(
1553 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
1554 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_REQ_TYPE_NOTSUPP));
1555 
1556 		break;
1557 
1558 	default:
1559 		pr_notice("unknown management function 0x%x\n",
1560 			MANAGEMENT_ORB_FUNCTION(be32_to_cpu(req->orb.misc)));
1561 
1562 		req->status.status = cpu_to_be32(
1563 			STATUS_BLOCK_RESP(STATUS_RESP_REQUEST_COMPLETE) |
1564 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_REQ_TYPE_NOTSUPP));
1565 
1566 		break;
1567 	}
1568 
1569 	req->status.status |= cpu_to_be32(
1570 		STATUS_BLOCK_SRC(1) | /* Response to ORB, next_ORB absent */
1571 		STATUS_BLOCK_LEN(DIV_ROUND_UP(status_data_len, 4) + 1) |
1572 		STATUS_BLOCK_ORB_OFFSET_HIGH(agent->orb_offset >> 32));
1573 	req->status.orb_low = cpu_to_be32(agent->orb_offset);
1574 
1575 	/* write the status block back to the initiator */
1576 	ret = sbp_run_transaction(req->card, TCODE_WRITE_BLOCK_REQUEST,
1577 		req->node_addr, req->generation, req->speed,
1578 		sbp2_pointer_to_addr(&req->orb.status_fifo),
1579 		&req->status, 8 + status_data_len);
1580 	if (ret != RCODE_COMPLETE) {
1581 		pr_debug("mgt_orb status write failed: %x\n", ret);
1582 		goto out;
1583 	}
1584 
1585 out:
1586 	fw_card_put(req->card);
1587 	kfree(req);
1588 
1589 	spin_lock_bh(&agent->lock);
1590 	agent->state = MANAGEMENT_AGENT_STATE_IDLE;
1591 	spin_unlock_bh(&agent->lock);
1592 }
1593 
1594 static void sbp_mgt_agent_rw(struct fw_card *card,
1595 	struct fw_request *request, int tcode, int destination, int source,
1596 	int generation, unsigned long long offset, void *data, size_t length,
1597 	void *callback_data)
1598 {
1599 	struct sbp_management_agent *agent = callback_data;
1600 	struct sbp2_pointer *ptr = data;
1601 	int rcode = RCODE_ADDRESS_ERROR;
1602 
1603 	if (!agent->tport->enable)
1604 		goto out;
1605 
1606 	if ((offset != agent->handler.offset) || (length != 8))
1607 		goto out;
1608 
1609 	if (tcode == TCODE_WRITE_BLOCK_REQUEST) {
1610 		struct sbp_management_request *req;
1611 		int prev_state;
1612 
1613 		spin_lock_bh(&agent->lock);
1614 		prev_state = agent->state;
1615 		agent->state = MANAGEMENT_AGENT_STATE_BUSY;
1616 		spin_unlock_bh(&agent->lock);
1617 
1618 		if (prev_state == MANAGEMENT_AGENT_STATE_BUSY) {
1619 			pr_notice("ignoring management request while busy\n");
1620 			rcode = RCODE_CONFLICT_ERROR;
1621 			goto out;
1622 		}
1623 		req = kzalloc(sizeof(*req), GFP_ATOMIC);
1624 		if (!req) {
1625 			rcode = RCODE_CONFLICT_ERROR;
1626 			goto out;
1627 		}
1628 
1629 		req->card = fw_card_get(card);
1630 		req->generation = generation;
1631 		req->node_addr = source;
1632 		req->speed = fw_get_request_speed(request);
1633 
1634 		agent->orb_offset = sbp2_pointer_to_addr(ptr);
1635 		agent->request = req;
1636 
1637 		queue_work(system_unbound_wq, &agent->work);
1638 		rcode = RCODE_COMPLETE;
1639 	} else if (tcode == TCODE_READ_BLOCK_REQUEST) {
1640 		addr_to_sbp2_pointer(agent->orb_offset, ptr);
1641 		rcode = RCODE_COMPLETE;
1642 	} else {
1643 		rcode = RCODE_TYPE_ERROR;
1644 	}
1645 
1646 out:
1647 	fw_send_response(card, request, rcode);
1648 }
1649 
1650 static struct sbp_management_agent *sbp_management_agent_register(
1651 		struct sbp_tport *tport)
1652 {
1653 	int ret;
1654 	struct sbp_management_agent *agent;
1655 
1656 	agent = kmalloc(sizeof(*agent), GFP_KERNEL);
1657 	if (!agent)
1658 		return ERR_PTR(-ENOMEM);
1659 
1660 	spin_lock_init(&agent->lock);
1661 	agent->tport = tport;
1662 	agent->handler.length = 0x08;
1663 	agent->handler.address_callback = sbp_mgt_agent_rw;
1664 	agent->handler.callback_data = agent;
1665 	agent->state = MANAGEMENT_AGENT_STATE_IDLE;
1666 	INIT_WORK(&agent->work, sbp_mgt_agent_process);
1667 	agent->orb_offset = 0;
1668 	agent->request = NULL;
1669 
1670 	ret = fw_core_add_address_handler(&agent->handler,
1671 			&sbp_register_region);
1672 	if (ret < 0) {
1673 		kfree(agent);
1674 		return ERR_PTR(ret);
1675 	}
1676 
1677 	return agent;
1678 }
1679 
1680 static void sbp_management_agent_unregister(struct sbp_management_agent *agent)
1681 {
1682 	fw_core_remove_address_handler(&agent->handler);
1683 	cancel_work_sync(&agent->work);
1684 	kfree(agent);
1685 }
1686 
1687 static int sbp_check_true(struct se_portal_group *se_tpg)
1688 {
1689 	return 1;
1690 }
1691 
1692 static int sbp_check_false(struct se_portal_group *se_tpg)
1693 {
1694 	return 0;
1695 }
1696 
1697 static char *sbp_get_fabric_name(void)
1698 {
1699 	return "sbp";
1700 }
1701 
1702 static char *sbp_get_fabric_wwn(struct se_portal_group *se_tpg)
1703 {
1704 	struct sbp_tpg *tpg = container_of(se_tpg, struct sbp_tpg, se_tpg);
1705 	struct sbp_tport *tport = tpg->tport;
1706 
1707 	return &tport->tport_name[0];
1708 }
1709 
1710 static u16 sbp_get_tag(struct se_portal_group *se_tpg)
1711 {
1712 	struct sbp_tpg *tpg = container_of(se_tpg, struct sbp_tpg, se_tpg);
1713 	return tpg->tport_tpgt;
1714 }
1715 
1716 static u32 sbp_tpg_get_inst_index(struct se_portal_group *se_tpg)
1717 {
1718 	return 1;
1719 }
1720 
1721 static void sbp_release_cmd(struct se_cmd *se_cmd)
1722 {
1723 	struct sbp_target_request *req = container_of(se_cmd,
1724 			struct sbp_target_request, se_cmd);
1725 
1726 	sbp_free_request(req);
1727 }
1728 
1729 static u32 sbp_sess_get_index(struct se_session *se_sess)
1730 {
1731 	return 0;
1732 }
1733 
1734 static int sbp_write_pending(struct se_cmd *se_cmd)
1735 {
1736 	struct sbp_target_request *req = container_of(se_cmd,
1737 			struct sbp_target_request, se_cmd);
1738 	int ret;
1739 
1740 	ret = sbp_rw_data(req);
1741 	if (ret) {
1742 		req->status.status |= cpu_to_be32(
1743 			STATUS_BLOCK_RESP(
1744 				STATUS_RESP_TRANSPORT_FAILURE) |
1745 			STATUS_BLOCK_DEAD(0) |
1746 			STATUS_BLOCK_LEN(1) |
1747 			STATUS_BLOCK_SBP_STATUS(
1748 				SBP_STATUS_UNSPECIFIED_ERROR));
1749 		sbp_send_status(req);
1750 		return ret;
1751 	}
1752 
1753 	target_execute_cmd(se_cmd);
1754 	return 0;
1755 }
1756 
1757 static int sbp_write_pending_status(struct se_cmd *se_cmd)
1758 {
1759 	return 0;
1760 }
1761 
1762 static void sbp_set_default_node_attrs(struct se_node_acl *nacl)
1763 {
1764 	return;
1765 }
1766 
1767 static int sbp_get_cmd_state(struct se_cmd *se_cmd)
1768 {
1769 	return 0;
1770 }
1771 
1772 static int sbp_queue_data_in(struct se_cmd *se_cmd)
1773 {
1774 	struct sbp_target_request *req = container_of(se_cmd,
1775 			struct sbp_target_request, se_cmd);
1776 	int ret;
1777 
1778 	ret = sbp_rw_data(req);
1779 	if (ret) {
1780 		req->status.status |= cpu_to_be32(
1781 			STATUS_BLOCK_RESP(STATUS_RESP_TRANSPORT_FAILURE) |
1782 			STATUS_BLOCK_DEAD(0) |
1783 			STATUS_BLOCK_LEN(1) |
1784 			STATUS_BLOCK_SBP_STATUS(SBP_STATUS_UNSPECIFIED_ERROR));
1785 		sbp_send_status(req);
1786 		return ret;
1787 	}
1788 
1789 	return sbp_send_sense(req);
1790 }
1791 
1792 /*
1793  * Called after command (no data transfer) or after the write (to device)
1794  * operation is completed
1795  */
1796 static int sbp_queue_status(struct se_cmd *se_cmd)
1797 {
1798 	struct sbp_target_request *req = container_of(se_cmd,
1799 			struct sbp_target_request, se_cmd);
1800 
1801 	return sbp_send_sense(req);
1802 }
1803 
1804 static void sbp_queue_tm_rsp(struct se_cmd *se_cmd)
1805 {
1806 }
1807 
1808 static void sbp_aborted_task(struct se_cmd *se_cmd)
1809 {
1810 	return;
1811 }
1812 
1813 static int sbp_check_stop_free(struct se_cmd *se_cmd)
1814 {
1815 	struct sbp_target_request *req = container_of(se_cmd,
1816 			struct sbp_target_request, se_cmd);
1817 
1818 	return transport_generic_free_cmd(&req->se_cmd, 0);
1819 }
1820 
1821 static int sbp_count_se_tpg_luns(struct se_portal_group *tpg)
1822 {
1823 	struct se_lun *lun;
1824 	int count = 0;
1825 
1826 	rcu_read_lock();
1827 	hlist_for_each_entry_rcu(lun, &tpg->tpg_lun_hlist, link)
1828 		count++;
1829 	rcu_read_unlock();
1830 
1831 	return count;
1832 }
1833 
1834 static int sbp_update_unit_directory(struct sbp_tport *tport)
1835 {
1836 	struct se_lun *lun;
1837 	int num_luns, num_entries, idx = 0, mgt_agt_addr, ret;
1838 	u32 *data;
1839 
1840 	if (tport->unit_directory.data) {
1841 		fw_core_remove_descriptor(&tport->unit_directory);
1842 		kfree(tport->unit_directory.data);
1843 		tport->unit_directory.data = NULL;
1844 	}
1845 
1846 	if (!tport->enable || !tport->tpg)
1847 		return 0;
1848 
1849 	num_luns = sbp_count_se_tpg_luns(&tport->tpg->se_tpg);
1850 
1851 	/*
1852 	 * Number of entries in the final unit directory:
1853 	 *  - all of those in the template
1854 	 *  - management_agent
1855 	 *  - unit_characteristics
1856 	 *  - reconnect_timeout
1857 	 *  - unit unique ID
1858 	 *  - one for each LUN
1859 	 *
1860 	 *  MUST NOT include leaf or sub-directory entries
1861 	 */
1862 	num_entries = ARRAY_SIZE(sbp_unit_directory_template) + 4 + num_luns;
1863 
1864 	if (tport->directory_id != -1)
1865 		num_entries++;
1866 
1867 	/* allocate num_entries + 4 for the header and unique ID leaf */
1868 	data = kcalloc((num_entries + 4), sizeof(u32), GFP_KERNEL);
1869 	if (!data)
1870 		return -ENOMEM;
1871 
1872 	/* directory_length */
1873 	data[idx++] = num_entries << 16;
1874 
1875 	/* directory_id */
1876 	if (tport->directory_id != -1)
1877 		data[idx++] = (CSR_DIRECTORY_ID << 24) | tport->directory_id;
1878 
1879 	/* unit directory template */
1880 	memcpy(&data[idx], sbp_unit_directory_template,
1881 			sizeof(sbp_unit_directory_template));
1882 	idx += ARRAY_SIZE(sbp_unit_directory_template);
1883 
1884 	/* management_agent */
1885 	mgt_agt_addr = (tport->mgt_agt->handler.offset - CSR_REGISTER_BASE) / 4;
1886 	data[idx++] = 0x54000000 | (mgt_agt_addr & 0x00ffffff);
1887 
1888 	/* unit_characteristics */
1889 	data[idx++] = 0x3a000000 |
1890 		(((tport->mgt_orb_timeout * 2) << 8) & 0xff00) |
1891 		SBP_ORB_FETCH_SIZE;
1892 
1893 	/* reconnect_timeout */
1894 	data[idx++] = 0x3d000000 | (tport->max_reconnect_timeout & 0xffff);
1895 
1896 	/* unit unique ID (leaf is just after LUNs) */
1897 	data[idx++] = 0x8d000000 | (num_luns + 1);
1898 
1899 	rcu_read_lock();
1900 	hlist_for_each_entry_rcu(lun, &tport->tpg->se_tpg.tpg_lun_hlist, link) {
1901 		struct se_device *dev;
1902 		int type;
1903 		/*
1904 		 * rcu_dereference_raw protected by se_lun->lun_group symlink
1905 		 * reference to se_device->dev_group.
1906 		 */
1907 		dev = rcu_dereference_raw(lun->lun_se_dev);
1908 		type = dev->transport->get_device_type(dev);
1909 
1910 		/* logical_unit_number */
1911 		data[idx++] = 0x14000000 |
1912 			((type << 16) & 0x1f0000) |
1913 			(lun->unpacked_lun & 0xffff);
1914 	}
1915 	rcu_read_unlock();
1916 
1917 	/* unit unique ID leaf */
1918 	data[idx++] = 2 << 16;
1919 	data[idx++] = tport->guid >> 32;
1920 	data[idx++] = tport->guid;
1921 
1922 	tport->unit_directory.length = idx;
1923 	tport->unit_directory.key = (CSR_DIRECTORY | CSR_UNIT) << 24;
1924 	tport->unit_directory.data = data;
1925 
1926 	ret = fw_core_add_descriptor(&tport->unit_directory);
1927 	if (ret < 0) {
1928 		kfree(tport->unit_directory.data);
1929 		tport->unit_directory.data = NULL;
1930 	}
1931 
1932 	return ret;
1933 }
1934 
1935 static ssize_t sbp_parse_wwn(const char *name, u64 *wwn)
1936 {
1937 	const char *cp;
1938 	char c, nibble;
1939 	int pos = 0, err;
1940 
1941 	*wwn = 0;
1942 	for (cp = name; cp < &name[SBP_NAMELEN - 1]; cp++) {
1943 		c = *cp;
1944 		if (c == '\n' && cp[1] == '\0')
1945 			continue;
1946 		if (c == '\0') {
1947 			err = 2;
1948 			if (pos != 16)
1949 				goto fail;
1950 			return cp - name;
1951 		}
1952 		err = 3;
1953 		if (isdigit(c))
1954 			nibble = c - '0';
1955 		else if (isxdigit(c))
1956 			nibble = tolower(c) - 'a' + 10;
1957 		else
1958 			goto fail;
1959 		*wwn = (*wwn << 4) | nibble;
1960 		pos++;
1961 	}
1962 	err = 4;
1963 fail:
1964 	printk(KERN_INFO "err %u len %zu pos %u\n",
1965 			err, cp - name, pos);
1966 	return -1;
1967 }
1968 
1969 static ssize_t sbp_format_wwn(char *buf, size_t len, u64 wwn)
1970 {
1971 	return snprintf(buf, len, "%016llx", wwn);
1972 }
1973 
1974 static int sbp_init_nodeacl(struct se_node_acl *se_nacl, const char *name)
1975 {
1976 	u64 guid = 0;
1977 
1978 	if (sbp_parse_wwn(name, &guid) < 0)
1979 		return -EINVAL;
1980 	return 0;
1981 }
1982 
1983 static int sbp_post_link_lun(
1984 		struct se_portal_group *se_tpg,
1985 		struct se_lun *se_lun)
1986 {
1987 	struct sbp_tpg *tpg = container_of(se_tpg, struct sbp_tpg, se_tpg);
1988 
1989 	return sbp_update_unit_directory(tpg->tport);
1990 }
1991 
1992 static void sbp_pre_unlink_lun(
1993 		struct se_portal_group *se_tpg,
1994 		struct se_lun *se_lun)
1995 {
1996 	struct sbp_tpg *tpg = container_of(se_tpg, struct sbp_tpg, se_tpg);
1997 	struct sbp_tport *tport = tpg->tport;
1998 	int ret;
1999 
2000 	if (sbp_count_se_tpg_luns(&tpg->se_tpg) == 0)
2001 		tport->enable = 0;
2002 
2003 	ret = sbp_update_unit_directory(tport);
2004 	if (ret < 0)
2005 		pr_err("unlink LUN: failed to update unit directory\n");
2006 }
2007 
2008 static struct se_portal_group *sbp_make_tpg(
2009 		struct se_wwn *wwn,
2010 		struct config_group *group,
2011 		const char *name)
2012 {
2013 	struct sbp_tport *tport =
2014 		container_of(wwn, struct sbp_tport, tport_wwn);
2015 
2016 	struct sbp_tpg *tpg;
2017 	unsigned long tpgt;
2018 	int ret;
2019 
2020 	if (strstr(name, "tpgt_") != name)
2021 		return ERR_PTR(-EINVAL);
2022 	if (kstrtoul(name + 5, 10, &tpgt) || tpgt > UINT_MAX)
2023 		return ERR_PTR(-EINVAL);
2024 
2025 	if (tport->tpg) {
2026 		pr_err("Only one TPG per Unit is possible.\n");
2027 		return ERR_PTR(-EBUSY);
2028 	}
2029 
2030 	tpg = kzalloc(sizeof(*tpg), GFP_KERNEL);
2031 	if (!tpg)
2032 		return ERR_PTR(-ENOMEM);
2033 
2034 	tpg->tport = tport;
2035 	tpg->tport_tpgt = tpgt;
2036 	tport->tpg = tpg;
2037 
2038 	/* default attribute values */
2039 	tport->enable = 0;
2040 	tport->directory_id = -1;
2041 	tport->mgt_orb_timeout = 15;
2042 	tport->max_reconnect_timeout = 5;
2043 	tport->max_logins_per_lun = 1;
2044 
2045 	tport->mgt_agt = sbp_management_agent_register(tport);
2046 	if (IS_ERR(tport->mgt_agt)) {
2047 		ret = PTR_ERR(tport->mgt_agt);
2048 		goto out_free_tpg;
2049 	}
2050 
2051 	ret = core_tpg_register(wwn, &tpg->se_tpg, SCSI_PROTOCOL_SBP);
2052 	if (ret < 0)
2053 		goto out_unreg_mgt_agt;
2054 
2055 	return &tpg->se_tpg;
2056 
2057 out_unreg_mgt_agt:
2058 	sbp_management_agent_unregister(tport->mgt_agt);
2059 out_free_tpg:
2060 	tport->tpg = NULL;
2061 	kfree(tpg);
2062 	return ERR_PTR(ret);
2063 }
2064 
2065 static void sbp_drop_tpg(struct se_portal_group *se_tpg)
2066 {
2067 	struct sbp_tpg *tpg = container_of(se_tpg, struct sbp_tpg, se_tpg);
2068 	struct sbp_tport *tport = tpg->tport;
2069 
2070 	core_tpg_deregister(se_tpg);
2071 	sbp_management_agent_unregister(tport->mgt_agt);
2072 	tport->tpg = NULL;
2073 	kfree(tpg);
2074 }
2075 
2076 static struct se_wwn *sbp_make_tport(
2077 		struct target_fabric_configfs *tf,
2078 		struct config_group *group,
2079 		const char *name)
2080 {
2081 	struct sbp_tport *tport;
2082 	u64 guid = 0;
2083 
2084 	if (sbp_parse_wwn(name, &guid) < 0)
2085 		return ERR_PTR(-EINVAL);
2086 
2087 	tport = kzalloc(sizeof(*tport), GFP_KERNEL);
2088 	if (!tport)
2089 		return ERR_PTR(-ENOMEM);
2090 
2091 	tport->guid = guid;
2092 	sbp_format_wwn(tport->tport_name, SBP_NAMELEN, guid);
2093 
2094 	return &tport->tport_wwn;
2095 }
2096 
2097 static void sbp_drop_tport(struct se_wwn *wwn)
2098 {
2099 	struct sbp_tport *tport =
2100 		container_of(wwn, struct sbp_tport, tport_wwn);
2101 
2102 	kfree(tport);
2103 }
2104 
2105 static ssize_t sbp_wwn_version_show(struct config_item *item, char *page)
2106 {
2107 	return sprintf(page, "FireWire SBP fabric module %s\n", SBP_VERSION);
2108 }
2109 
2110 CONFIGFS_ATTR_RO(sbp_wwn_, version);
2111 
2112 static struct configfs_attribute *sbp_wwn_attrs[] = {
2113 	&sbp_wwn_attr_version,
2114 	NULL,
2115 };
2116 
2117 static ssize_t sbp_tpg_directory_id_show(struct config_item *item, char *page)
2118 {
2119 	struct se_portal_group *se_tpg = to_tpg(item);
2120 	struct sbp_tpg *tpg = container_of(se_tpg, struct sbp_tpg, se_tpg);
2121 	struct sbp_tport *tport = tpg->tport;
2122 
2123 	if (tport->directory_id == -1)
2124 		return sprintf(page, "implicit\n");
2125 	else
2126 		return sprintf(page, "%06x\n", tport->directory_id);
2127 }
2128 
2129 static ssize_t sbp_tpg_directory_id_store(struct config_item *item,
2130 		const char *page, size_t count)
2131 {
2132 	struct se_portal_group *se_tpg = to_tpg(item);
2133 	struct sbp_tpg *tpg = container_of(se_tpg, struct sbp_tpg, se_tpg);
2134 	struct sbp_tport *tport = tpg->tport;
2135 	unsigned long val;
2136 
2137 	if (tport->enable) {
2138 		pr_err("Cannot change the directory_id on an active target.\n");
2139 		return -EBUSY;
2140 	}
2141 
2142 	if (strstr(page, "implicit") == page) {
2143 		tport->directory_id = -1;
2144 	} else {
2145 		if (kstrtoul(page, 16, &val) < 0)
2146 			return -EINVAL;
2147 		if (val > 0xffffff)
2148 			return -EINVAL;
2149 
2150 		tport->directory_id = val;
2151 	}
2152 
2153 	return count;
2154 }
2155 
2156 static ssize_t sbp_tpg_enable_show(struct config_item *item, char *page)
2157 {
2158 	struct se_portal_group *se_tpg = to_tpg(item);
2159 	struct sbp_tpg *tpg = container_of(se_tpg, struct sbp_tpg, se_tpg);
2160 	struct sbp_tport *tport = tpg->tport;
2161 	return sprintf(page, "%d\n", tport->enable);
2162 }
2163 
2164 static ssize_t sbp_tpg_enable_store(struct config_item *item,
2165 		const char *page, size_t count)
2166 {
2167 	struct se_portal_group *se_tpg = to_tpg(item);
2168 	struct sbp_tpg *tpg = container_of(se_tpg, struct sbp_tpg, se_tpg);
2169 	struct sbp_tport *tport = tpg->tport;
2170 	unsigned long val;
2171 	int ret;
2172 
2173 	if (kstrtoul(page, 0, &val) < 0)
2174 		return -EINVAL;
2175 	if ((val != 0) && (val != 1))
2176 		return -EINVAL;
2177 
2178 	if (tport->enable == val)
2179 		return count;
2180 
2181 	if (val) {
2182 		if (sbp_count_se_tpg_luns(&tpg->se_tpg) == 0) {
2183 			pr_err("Cannot enable a target with no LUNs!\n");
2184 			return -EINVAL;
2185 		}
2186 	} else {
2187 		/* XXX: force-shutdown sessions instead? */
2188 		spin_lock_bh(&se_tpg->session_lock);
2189 		if (!list_empty(&se_tpg->tpg_sess_list)) {
2190 			spin_unlock_bh(&se_tpg->session_lock);
2191 			return -EBUSY;
2192 		}
2193 		spin_unlock_bh(&se_tpg->session_lock);
2194 	}
2195 
2196 	tport->enable = val;
2197 
2198 	ret = sbp_update_unit_directory(tport);
2199 	if (ret < 0) {
2200 		pr_err("Could not update Config ROM\n");
2201 		return ret;
2202 	}
2203 
2204 	return count;
2205 }
2206 
2207 CONFIGFS_ATTR(sbp_tpg_, directory_id);
2208 CONFIGFS_ATTR(sbp_tpg_, enable);
2209 
2210 static struct configfs_attribute *sbp_tpg_base_attrs[] = {
2211 	&sbp_tpg_attr_directory_id,
2212 	&sbp_tpg_attr_enable,
2213 	NULL,
2214 };
2215 
2216 static ssize_t sbp_tpg_attrib_mgt_orb_timeout_show(struct config_item *item,
2217 		char *page)
2218 {
2219 	struct se_portal_group *se_tpg = attrib_to_tpg(item);
2220 	struct sbp_tpg *tpg = container_of(se_tpg, struct sbp_tpg, se_tpg);
2221 	struct sbp_tport *tport = tpg->tport;
2222 	return sprintf(page, "%d\n", tport->mgt_orb_timeout);
2223 }
2224 
2225 static ssize_t sbp_tpg_attrib_mgt_orb_timeout_store(struct config_item *item,
2226 		const char *page, size_t count)
2227 {
2228 	struct se_portal_group *se_tpg = attrib_to_tpg(item);
2229 	struct sbp_tpg *tpg = container_of(se_tpg, struct sbp_tpg, se_tpg);
2230 	struct sbp_tport *tport = tpg->tport;
2231 	unsigned long val;
2232 	int ret;
2233 
2234 	if (kstrtoul(page, 0, &val) < 0)
2235 		return -EINVAL;
2236 	if ((val < 1) || (val > 127))
2237 		return -EINVAL;
2238 
2239 	if (tport->mgt_orb_timeout == val)
2240 		return count;
2241 
2242 	tport->mgt_orb_timeout = val;
2243 
2244 	ret = sbp_update_unit_directory(tport);
2245 	if (ret < 0)
2246 		return ret;
2247 
2248 	return count;
2249 }
2250 
2251 static ssize_t sbp_tpg_attrib_max_reconnect_timeout_show(struct config_item *item,
2252 		char *page)
2253 {
2254 	struct se_portal_group *se_tpg = attrib_to_tpg(item);
2255 	struct sbp_tpg *tpg = container_of(se_tpg, struct sbp_tpg, se_tpg);
2256 	struct sbp_tport *tport = tpg->tport;
2257 	return sprintf(page, "%d\n", tport->max_reconnect_timeout);
2258 }
2259 
2260 static ssize_t sbp_tpg_attrib_max_reconnect_timeout_store(struct config_item *item,
2261 		const char *page, size_t count)
2262 {
2263 	struct se_portal_group *se_tpg = attrib_to_tpg(item);
2264 	struct sbp_tpg *tpg = container_of(se_tpg, struct sbp_tpg, se_tpg);
2265 	struct sbp_tport *tport = tpg->tport;
2266 	unsigned long val;
2267 	int ret;
2268 
2269 	if (kstrtoul(page, 0, &val) < 0)
2270 		return -EINVAL;
2271 	if ((val < 1) || (val > 32767))
2272 		return -EINVAL;
2273 
2274 	if (tport->max_reconnect_timeout == val)
2275 		return count;
2276 
2277 	tport->max_reconnect_timeout = val;
2278 
2279 	ret = sbp_update_unit_directory(tport);
2280 	if (ret < 0)
2281 		return ret;
2282 
2283 	return count;
2284 }
2285 
2286 static ssize_t sbp_tpg_attrib_max_logins_per_lun_show(struct config_item *item,
2287 		char *page)
2288 {
2289 	struct se_portal_group *se_tpg = attrib_to_tpg(item);
2290 	struct sbp_tpg *tpg = container_of(se_tpg, struct sbp_tpg, se_tpg);
2291 	struct sbp_tport *tport = tpg->tport;
2292 	return sprintf(page, "%d\n", tport->max_logins_per_lun);
2293 }
2294 
2295 static ssize_t sbp_tpg_attrib_max_logins_per_lun_store(struct config_item *item,
2296 		const char *page, size_t count)
2297 {
2298 	struct se_portal_group *se_tpg = attrib_to_tpg(item);
2299 	struct sbp_tpg *tpg = container_of(se_tpg, struct sbp_tpg, se_tpg);
2300 	struct sbp_tport *tport = tpg->tport;
2301 	unsigned long val;
2302 
2303 	if (kstrtoul(page, 0, &val) < 0)
2304 		return -EINVAL;
2305 	if ((val < 1) || (val > 127))
2306 		return -EINVAL;
2307 
2308 	/* XXX: also check against current count? */
2309 
2310 	tport->max_logins_per_lun = val;
2311 
2312 	return count;
2313 }
2314 
2315 CONFIGFS_ATTR(sbp_tpg_attrib_, mgt_orb_timeout);
2316 CONFIGFS_ATTR(sbp_tpg_attrib_, max_reconnect_timeout);
2317 CONFIGFS_ATTR(sbp_tpg_attrib_, max_logins_per_lun);
2318 
2319 static struct configfs_attribute *sbp_tpg_attrib_attrs[] = {
2320 	&sbp_tpg_attrib_attr_mgt_orb_timeout,
2321 	&sbp_tpg_attrib_attr_max_reconnect_timeout,
2322 	&sbp_tpg_attrib_attr_max_logins_per_lun,
2323 	NULL,
2324 };
2325 
2326 static const struct target_core_fabric_ops sbp_ops = {
2327 	.module				= THIS_MODULE,
2328 	.name				= "sbp",
2329 	.get_fabric_name		= sbp_get_fabric_name,
2330 	.tpg_get_wwn			= sbp_get_fabric_wwn,
2331 	.tpg_get_tag			= sbp_get_tag,
2332 	.tpg_check_demo_mode		= sbp_check_true,
2333 	.tpg_check_demo_mode_cache	= sbp_check_true,
2334 	.tpg_check_demo_mode_write_protect = sbp_check_false,
2335 	.tpg_check_prod_mode_write_protect = sbp_check_false,
2336 	.tpg_get_inst_index		= sbp_tpg_get_inst_index,
2337 	.release_cmd			= sbp_release_cmd,
2338 	.sess_get_index			= sbp_sess_get_index,
2339 	.write_pending			= sbp_write_pending,
2340 	.write_pending_status		= sbp_write_pending_status,
2341 	.set_default_node_attributes	= sbp_set_default_node_attrs,
2342 	.get_cmd_state			= sbp_get_cmd_state,
2343 	.queue_data_in			= sbp_queue_data_in,
2344 	.queue_status			= sbp_queue_status,
2345 	.queue_tm_rsp			= sbp_queue_tm_rsp,
2346 	.aborted_task			= sbp_aborted_task,
2347 	.check_stop_free		= sbp_check_stop_free,
2348 
2349 	.fabric_make_wwn		= sbp_make_tport,
2350 	.fabric_drop_wwn		= sbp_drop_tport,
2351 	.fabric_make_tpg		= sbp_make_tpg,
2352 	.fabric_drop_tpg		= sbp_drop_tpg,
2353 	.fabric_post_link		= sbp_post_link_lun,
2354 	.fabric_pre_unlink		= sbp_pre_unlink_lun,
2355 	.fabric_make_np			= NULL,
2356 	.fabric_drop_np			= NULL,
2357 	.fabric_init_nodeacl		= sbp_init_nodeacl,
2358 
2359 	.tfc_wwn_attrs			= sbp_wwn_attrs,
2360 	.tfc_tpg_base_attrs		= sbp_tpg_base_attrs,
2361 	.tfc_tpg_attrib_attrs		= sbp_tpg_attrib_attrs,
2362 };
2363 
2364 static int __init sbp_init(void)
2365 {
2366 	return target_register_template(&sbp_ops);
2367 };
2368 
2369 static void __exit sbp_exit(void)
2370 {
2371 	target_unregister_template(&sbp_ops);
2372 };
2373 
2374 MODULE_DESCRIPTION("FireWire SBP fabric driver");
2375 MODULE_LICENSE("GPL");
2376 module_init(sbp_init);
2377 module_exit(sbp_exit);
2378