1/*******************************************************************************
2 * Filename:  tcm_fc.c
3 *
4 * This file contains the configfs implementation for TCM_fc fabric node.
5 * Based on tcm_loop_configfs.c
6 *
7 * Copyright (c) 2010 Cisco Systems, Inc.
8 * Copyright (c) 2009,2010 Rising Tide, Inc.
9 * Copyright (c) 2009,2010 Linux-iSCSI.org
10 *
11 * Copyright (c) 2009,2010 Nicholas A. Bellinger <nab@linux-iscsi.org>
12 *
13 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License as published by
15 * the Free Software Foundation; either version 2 of the License, or
16 * (at your option) any later version.
17 *
18 * This program is distributed in the hope that it will be useful,
19 * but WITHOUT ANY WARRANTY; without even the implied warranty of
20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
21 * GNU General Public License for more details.
22 ****************************************************************************/
23
24#include <linux/module.h>
25#include <linux/moduleparam.h>
26#include <generated/utsrelease.h>
27#include <linux/utsname.h>
28#include <linux/init.h>
29#include <linux/slab.h>
30#include <linux/kthread.h>
31#include <linux/types.h>
32#include <linux/string.h>
33#include <linux/configfs.h>
34#include <linux/kernel.h>
35#include <linux/ctype.h>
36#include <asm/unaligned.h>
37#include <scsi/libfc.h>
38
39#include <target/target_core_base.h>
40#include <target/target_core_fabric.h>
41
42#include "tcm_fc.h"
43
44static LIST_HEAD(ft_wwn_list);
45DEFINE_MUTEX(ft_lport_lock);
46
47unsigned int ft_debug_logging;
48module_param_named(debug_logging, ft_debug_logging, int, S_IRUGO|S_IWUSR);
49MODULE_PARM_DESC(debug_logging, "a bit mask of logging levels");
50
51/*
52 * Parse WWN.
53 * If strict, we require lower-case hex and colon separators to be sure
54 * the name is the same as what would be generated by ft_format_wwn()
55 * so the name and wwn are mapped one-to-one.
56 */
57static ssize_t ft_parse_wwn(const char *name, u64 *wwn, int strict)
58{
59	const char *cp;
60	char c;
61	u32 byte = 0;
62	u32 pos = 0;
63	u32 err;
64	int val;
65
66	*wwn = 0;
67	for (cp = name; cp < &name[FT_NAMELEN - 1]; cp++) {
68		c = *cp;
69		if (c == '\n' && cp[1] == '\0')
70			continue;
71		if (strict && pos++ == 2 && byte++ < 7) {
72			pos = 0;
73			if (c == ':')
74				continue;
75			err = 1;
76			goto fail;
77		}
78		if (c == '\0') {
79			err = 2;
80			if (strict && byte != 8)
81				goto fail;
82			return cp - name;
83		}
84		err = 3;
85		val = hex_to_bin(c);
86		if (val < 0 || (strict && isupper(c)))
87			goto fail;
88		*wwn = (*wwn << 4) | val;
89	}
90	err = 4;
91fail:
92	pr_debug("err %u len %zu pos %u byte %u\n",
93		    err, cp - name, pos, byte);
94	return -1;
95}
96
97ssize_t ft_format_wwn(char *buf, size_t len, u64 wwn)
98{
99	u8 b[8];
100
101	put_unaligned_be64(wwn, b);
102	return snprintf(buf, len,
103		 "%2.2x:%2.2x:%2.2x:%2.2x:%2.2x:%2.2x:%2.2x:%2.2x",
104		 b[0], b[1], b[2], b[3], b[4], b[5], b[6], b[7]);
105}
106
107static ssize_t ft_wwn_show(void *arg, char *buf)
108{
109	u64 *wwn = arg;
110	ssize_t len;
111
112	len = ft_format_wwn(buf, PAGE_SIZE - 2, *wwn);
113	buf[len++] = '\n';
114	return len;
115}
116
117static ssize_t ft_wwn_store(void *arg, const char *buf, size_t len)
118{
119	ssize_t ret;
120	u64 wwn;
121
122	ret = ft_parse_wwn(buf, &wwn, 0);
123	if (ret > 0)
124		*(u64 *)arg = wwn;
125	return ret;
126}
127
128/*
129 * ACL auth ops.
130 */
131
132static ssize_t ft_nacl_port_name_show(struct config_item *item, char *page)
133{
134	struct se_node_acl *se_nacl = acl_to_nacl(item);
135	struct ft_node_acl *acl = container_of(se_nacl,
136			struct ft_node_acl, se_node_acl);
137
138	return ft_wwn_show(&acl->node_auth.port_name, page);
139}
140
141static ssize_t ft_nacl_port_name_store(struct config_item *item,
142		const char *page, size_t count)
143{
144	struct se_node_acl *se_nacl = acl_to_nacl(item);
145	struct ft_node_acl *acl = container_of(se_nacl,
146			struct ft_node_acl, se_node_acl);
147
148	return ft_wwn_store(&acl->node_auth.port_name, page, count);
149}
150
151static ssize_t ft_nacl_node_name_show(struct config_item *item,
152		char *page)
153{
154	struct se_node_acl *se_nacl = acl_to_nacl(item);
155	struct ft_node_acl *acl = container_of(se_nacl,
156			struct ft_node_acl, se_node_acl);
157
158	return ft_wwn_show(&acl->node_auth.node_name, page);
159}
160
161static ssize_t ft_nacl_node_name_store(struct config_item *item,
162		const char *page, size_t count)
163{
164	struct se_node_acl *se_nacl = acl_to_nacl(item);
165	struct ft_node_acl *acl = container_of(se_nacl,
166			struct ft_node_acl, se_node_acl);
167
168	return ft_wwn_store(&acl->node_auth.node_name, page, count);
169}
170
171CONFIGFS_ATTR(ft_nacl_, node_name);
172CONFIGFS_ATTR(ft_nacl_, port_name);
173
174static struct configfs_attribute *ft_nacl_base_attrs[] = {
175	&ft_nacl_attr_port_name,
176	&ft_nacl_attr_node_name,
177	NULL,
178};
179
180/*
181 * ACL ops.
182 */
183
184/*
185 * Add ACL for an initiator.  The ACL is named arbitrarily.
186 * The port_name and/or node_name are attributes.
187 */
188static int ft_init_nodeacl(struct se_node_acl *nacl, const char *name)
189{
190	struct ft_node_acl *acl =
191		container_of(nacl, struct ft_node_acl, se_node_acl);
192	u64 wwpn;
193
194	if (ft_parse_wwn(name, &wwpn, 1) < 0)
195		return -EINVAL;
196
197	acl->node_auth.port_name = wwpn;
198	return 0;
199}
200
201struct ft_node_acl *ft_acl_get(struct ft_tpg *tpg, struct fc_rport_priv *rdata)
202{
203	struct ft_node_acl *found = NULL;
204	struct ft_node_acl *acl;
205	struct se_portal_group *se_tpg = &tpg->se_tpg;
206	struct se_node_acl *se_acl;
207
208	mutex_lock(&se_tpg->acl_node_mutex);
209	list_for_each_entry(se_acl, &se_tpg->acl_node_list, acl_list) {
210		acl = container_of(se_acl, struct ft_node_acl, se_node_acl);
211		pr_debug("acl %p port_name %llx\n",
212			acl, (unsigned long long)acl->node_auth.port_name);
213		if (acl->node_auth.port_name == rdata->ids.port_name ||
214		    acl->node_auth.node_name == rdata->ids.node_name) {
215			pr_debug("acl %p port_name %llx matched\n", acl,
216				    (unsigned long long)rdata->ids.port_name);
217			found = acl;
218			/* XXX need to hold onto ACL */
219			break;
220		}
221	}
222	mutex_unlock(&se_tpg->acl_node_mutex);
223	return found;
224}
225
226/*
227 * local_port port_group (tpg) ops.
228 */
229static struct se_portal_group *ft_add_tpg(
230	struct se_wwn *wwn,
231	struct config_group *group,
232	const char *name)
233{
234	struct ft_lport_wwn *ft_wwn;
235	struct ft_tpg *tpg;
236	struct workqueue_struct *wq;
237	unsigned long index;
238	int ret;
239
240	pr_debug("tcm_fc: add tpg %s\n", name);
241
242	/*
243	 * Name must be "tpgt_" followed by the index.
244	 */
245	if (strstr(name, "tpgt_") != name)
246		return NULL;
247
248	ret = kstrtoul(name + 5, 10, &index);
249	if (ret)
250		return NULL;
251	if (index > UINT_MAX)
252		return NULL;
253
254	if ((index != 1)) {
255		pr_err("Error, a single TPG=1 is used for HW port mappings\n");
256		return ERR_PTR(-ENOSYS);
257	}
258
259	ft_wwn = container_of(wwn, struct ft_lport_wwn, se_wwn);
260	tpg = kzalloc(sizeof(*tpg), GFP_KERNEL);
261	if (!tpg)
262		return NULL;
263	tpg->index = index;
264	tpg->lport_wwn = ft_wwn;
265	INIT_LIST_HEAD(&tpg->lun_list);
266
267	wq = alloc_workqueue("tcm_fc", 0, 1);
268	if (!wq) {
269		kfree(tpg);
270		return NULL;
271	}
272
273	ret = core_tpg_register(wwn, &tpg->se_tpg, SCSI_PROTOCOL_FCP);
274	if (ret < 0) {
275		destroy_workqueue(wq);
276		kfree(tpg);
277		return NULL;
278	}
279	tpg->workqueue = wq;
280
281	mutex_lock(&ft_lport_lock);
282	ft_wwn->tpg = tpg;
283	mutex_unlock(&ft_lport_lock);
284
285	return &tpg->se_tpg;
286}
287
288static void ft_del_tpg(struct se_portal_group *se_tpg)
289{
290	struct ft_tpg *tpg = container_of(se_tpg, struct ft_tpg, se_tpg);
291	struct ft_lport_wwn *ft_wwn = tpg->lport_wwn;
292
293	pr_debug("del tpg %s\n",
294		    config_item_name(&tpg->se_tpg.tpg_group.cg_item));
295
296	destroy_workqueue(tpg->workqueue);
297
298	/* Wait for sessions to be freed thru RCU, for BUG_ON below */
299	synchronize_rcu();
300
301	mutex_lock(&ft_lport_lock);
302	ft_wwn->tpg = NULL;
303	if (tpg->tport) {
304		tpg->tport->tpg = NULL;
305		tpg->tport = NULL;
306	}
307	mutex_unlock(&ft_lport_lock);
308
309	core_tpg_deregister(se_tpg);
310	kfree(tpg);
311}
312
313/*
314 * Verify that an lport is configured to use the tcm_fc module, and return
315 * the target port group that should be used.
316 *
317 * The caller holds ft_lport_lock.
318 */
319struct ft_tpg *ft_lport_find_tpg(struct fc_lport *lport)
320{
321	struct ft_lport_wwn *ft_wwn;
322
323	list_for_each_entry(ft_wwn, &ft_wwn_list, ft_wwn_node) {
324		if (ft_wwn->wwpn == lport->wwpn)
325			return ft_wwn->tpg;
326	}
327	return NULL;
328}
329
330/*
331 * target config instance ops.
332 */
333
334/*
335 * Add lport to allowed config.
336 * The name is the WWPN in lower-case ASCII, colon-separated bytes.
337 */
338static struct se_wwn *ft_add_wwn(
339	struct target_fabric_configfs *tf,
340	struct config_group *group,
341	const char *name)
342{
343	struct ft_lport_wwn *ft_wwn;
344	struct ft_lport_wwn *old_ft_wwn;
345	u64 wwpn;
346
347	pr_debug("add wwn %s\n", name);
348	if (ft_parse_wwn(name, &wwpn, 1) < 0)
349		return NULL;
350	ft_wwn = kzalloc(sizeof(*ft_wwn), GFP_KERNEL);
351	if (!ft_wwn)
352		return NULL;
353	ft_wwn->wwpn = wwpn;
354
355	mutex_lock(&ft_lport_lock);
356	list_for_each_entry(old_ft_wwn, &ft_wwn_list, ft_wwn_node) {
357		if (old_ft_wwn->wwpn == wwpn) {
358			mutex_unlock(&ft_lport_lock);
359			kfree(ft_wwn);
360			return NULL;
361		}
362	}
363	list_add_tail(&ft_wwn->ft_wwn_node, &ft_wwn_list);
364	ft_format_wwn(ft_wwn->name, sizeof(ft_wwn->name), wwpn);
365	mutex_unlock(&ft_lport_lock);
366
367	return &ft_wwn->se_wwn;
368}
369
370static void ft_del_wwn(struct se_wwn *wwn)
371{
372	struct ft_lport_wwn *ft_wwn = container_of(wwn,
373				struct ft_lport_wwn, se_wwn);
374
375	pr_debug("del wwn %s\n", ft_wwn->name);
376	mutex_lock(&ft_lport_lock);
377	list_del(&ft_wwn->ft_wwn_node);
378	mutex_unlock(&ft_lport_lock);
379
380	kfree(ft_wwn);
381}
382
383static ssize_t ft_wwn_version_show(struct config_item *item, char *page)
384{
385	return sprintf(page, "TCM FC " FT_VERSION " on %s/%s on "
386		""UTS_RELEASE"\n",  utsname()->sysname, utsname()->machine);
387}
388
389CONFIGFS_ATTR_RO(ft_wwn_, version);
390
391static struct configfs_attribute *ft_wwn_attrs[] = {
392	&ft_wwn_attr_version,
393	NULL,
394};
395
396static inline struct ft_tpg *ft_tpg(struct se_portal_group *se_tpg)
397{
398	return container_of(se_tpg, struct ft_tpg, se_tpg);
399}
400
401static char *ft_get_fabric_name(void)
402{
403	return "fc";
404}
405
406static char *ft_get_fabric_wwn(struct se_portal_group *se_tpg)
407{
408	return ft_tpg(se_tpg)->lport_wwn->name;
409}
410
411static u16 ft_get_tag(struct se_portal_group *se_tpg)
412{
413	/*
414	 * This tag is used when forming SCSI Name identifier in EVPD=1 0x83
415	 * to represent the SCSI Target Port.
416	 */
417	return ft_tpg(se_tpg)->index;
418}
419
420static int ft_check_false(struct se_portal_group *se_tpg)
421{
422	return 0;
423}
424
425static void ft_set_default_node_attr(struct se_node_acl *se_nacl)
426{
427}
428
429static u32 ft_tpg_get_inst_index(struct se_portal_group *se_tpg)
430{
431	return ft_tpg(se_tpg)->index;
432}
433
434static const struct target_core_fabric_ops ft_fabric_ops = {
435	.module =			THIS_MODULE,
436	.name =				"fc",
437	.node_acl_size =		sizeof(struct ft_node_acl),
438	.get_fabric_name =		ft_get_fabric_name,
439	.tpg_get_wwn =			ft_get_fabric_wwn,
440	.tpg_get_tag =			ft_get_tag,
441	.tpg_check_demo_mode =		ft_check_false,
442	.tpg_check_demo_mode_cache =	ft_check_false,
443	.tpg_check_demo_mode_write_protect = ft_check_false,
444	.tpg_check_prod_mode_write_protect = ft_check_false,
445	.tpg_get_inst_index =		ft_tpg_get_inst_index,
446	.check_stop_free =		ft_check_stop_free,
447	.release_cmd =			ft_release_cmd,
448	.shutdown_session =		ft_sess_shutdown,
449	.close_session =		ft_sess_close,
450	.sess_get_index =		ft_sess_get_index,
451	.sess_get_initiator_sid =	NULL,
452	.write_pending =		ft_write_pending,
453	.write_pending_status =		ft_write_pending_status,
454	.set_default_node_attributes =	ft_set_default_node_attr,
455	.get_cmd_state =		ft_get_cmd_state,
456	.queue_data_in =		ft_queue_data_in,
457	.queue_status =			ft_queue_status,
458	.queue_tm_rsp =			ft_queue_tm_resp,
459	.aborted_task =			ft_aborted_task,
460	/*
461	 * Setup function pointers for generic logic in
462	 * target_core_fabric_configfs.c
463	 */
464	.fabric_make_wwn =		&ft_add_wwn,
465	.fabric_drop_wwn =		&ft_del_wwn,
466	.fabric_make_tpg =		&ft_add_tpg,
467	.fabric_drop_tpg =		&ft_del_tpg,
468	.fabric_init_nodeacl =		&ft_init_nodeacl,
469
470	.tfc_wwn_attrs			= ft_wwn_attrs,
471	.tfc_tpg_nacl_base_attrs	= ft_nacl_base_attrs,
472};
473
474static struct notifier_block ft_notifier = {
475	.notifier_call = ft_lport_notify
476};
477
478static int __init ft_init(void)
479{
480	int ret;
481
482	ret = target_register_template(&ft_fabric_ops);
483	if (ret)
484		goto out;
485
486	ret = fc_fc4_register_provider(FC_TYPE_FCP, &ft_prov);
487	if (ret)
488		goto out_unregister_template;
489
490	blocking_notifier_chain_register(&fc_lport_notifier_head, &ft_notifier);
491	fc_lport_iterate(ft_lport_add, NULL);
492	return 0;
493
494out_unregister_template:
495	target_unregister_template(&ft_fabric_ops);
496out:
497	return ret;
498}
499
500static void __exit ft_exit(void)
501{
502	blocking_notifier_chain_unregister(&fc_lport_notifier_head,
503					   &ft_notifier);
504	fc_fc4_deregister_provider(FC_TYPE_FCP, &ft_prov);
505	fc_lport_iterate(ft_lport_del, NULL);
506	target_unregister_template(&ft_fabric_ops);
507	synchronize_rcu();
508}
509
510MODULE_DESCRIPTION("FC TCM fabric driver " FT_VERSION);
511MODULE_LICENSE("GPL");
512module_init(ft_init);
513module_exit(ft_exit);
514