summaryrefslogtreecommitdiff
path: root/drivers/scsi/scsi_transport_srp.c
blob: 21a045e0559ff7ad9a209742f55b020b99adcb6b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
/*
 * SCSI RDMA (SRP) transport class
 *
 * Copyright (C) 2007 FUJITA Tomonori <tomof@acm.org>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation, version 2 of the
 * License.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 */
#include <linux/init.h>
#include <linux/module.h>
#include <linux/jiffies.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/string.h>

#include <scsi/scsi.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_transport.h>
#include <scsi/scsi_transport_srp.h>
#include "scsi_transport_srp_internal.h"

struct srp_host_attrs {
	atomic_t next_port_id;
};
#define to_srp_host_attrs(host)	((struct srp_host_attrs *)(host)->shost_data)

#define SRP_HOST_ATTRS 0
#define SRP_RPORT_ATTRS 2

struct srp_internal {
	struct scsi_transport_template t;
	struct srp_function_template *f;

	struct device_attribute *host_attrs[SRP_HOST_ATTRS + 1];

	struct device_attribute *rport_attrs[SRP_RPORT_ATTRS + 1];
	struct device_attribute private_rport_attrs[SRP_RPORT_ATTRS];
	struct transport_container rport_attr_cont;
};

#define to_srp_internal(tmpl) container_of(tmpl, struct srp_internal, t)

#define	dev_to_rport(d)	container_of(d, struct srp_rport, dev)
#define transport_class_to_srp_rport(dev) dev_to_rport((dev)->parent)

static int srp_host_setup(struct transport_container *tc, struct device *dev,
			  struct device *cdev)
{
	struct Scsi_Host *shost = dev_to_shost(dev);
	struct srp_host_attrs *srp_host = to_srp_host_attrs(shost);

	atomic_set(&srp_host->next_port_id, 0);
	return 0;
}

static DECLARE_TRANSPORT_CLASS(srp_host_class, "srp_host", srp_host_setup,
			       NULL, NULL);

static DECLARE_TRANSPORT_CLASS(srp_rport_class, "srp_remote_ports",
			       NULL, NULL, NULL);

#define SETUP_TEMPLATE(attrb, field, perm, test, ro_test, ro_perm)	\
	i->private_##attrb[count] = dev_attr_##field;		\
	i->private_##attrb[count].attr.mode = perm;			\
	if (ro_test) {							\
		i->private_##attrb[count].attr.mode = ro_perm;		\
		i->private_##attrb[count].store = NULL;			\
	}								\
	i->attrb[count] = &i->private_##attrb[count];			\
	if (test)							\
		count++

#define SETUP_RPORT_ATTRIBUTE_RD(field)					\
	SETUP_TEMPLATE(rport_attrs, field, S_IRUGO, 1, 0, 0)

#define SETUP_RPORT_ATTRIBUTE_RW(field)					\
	SETUP_TEMPLATE(rport_attrs, field, S_IRUGO | S_IWUSR,		\
		       1, 1, S_IRUGO)

#define SRP_PID(p) \
	(p)->port_id[0], (p)->port_id[1], (p)->port_id[2], (p)->port_id[3], \
	(p)->port_id[4], (p)->port_id[5], (p)->port_id[6], (p)->port_id[7], \
	(p)->port_id[8], (p)->port_id[9], (p)->port_id[10], (p)->port_id[11], \
	(p)->port_id[12], (p)->port_id[13], (p)->port_id[14], (p)->port_id[15]

#define SRP_PID_FMT "%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:" \
	"%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x"

static ssize_t
show_srp_rport_id(struct device *dev, struct device_attribute *attr,
		  char *buf)
{
	struct srp_rport *rport = transport_class_to_srp_rport(dev);
	return sprintf(buf, SRP_PID_FMT "\n", SRP_PID(rport));
}

static DEVICE_ATTR(port_id, S_IRUGO, show_srp_rport_id, NULL);

static const struct {
	u32 value;
	char *name;
} srp_rport_role_names[] = {
	{SRP_RPORT_ROLE_INITIATOR, "SRP Initiator"},
	{SRP_RPORT_ROLE_TARGET, "SRP Target"},
};

static ssize_t
show_srp_rport_roles(struct device *dev, struct device_attribute *attr,
		     char *buf)
{
	struct srp_rport *rport = transport_class_to_srp_rport(dev);
	int i;
	char *name = NULL;

	for (i = 0; i < ARRAY_SIZE(srp_rport_role_names); i++)
		if (srp_rport_role_names[i].value == rport->roles) {
			name = srp_rport_role_names[i].name;
			break;
		}
	return sprintf(buf, "%s\n", name ? : "unknown");
}

static DEVICE_ATTR(roles, S_IRUGO, show_srp_rport_roles, NULL);

static void srp_rport_release(struct device *dev)
{
	struct srp_rport *rport = dev_to_rport(dev);

	put_device(dev->parent);
	kfree(rport);
}

static int scsi_is_srp_rport(const struct device *dev)
{
	return dev->release == srp_rport_release;
}

static int srp_rport_match(struct attribute_container *cont,
			   struct device *dev)
{
	struct Scsi_Host *shost;
	struct srp_internal *i;

	if (!scsi_is_srp_rport(dev))
		return 0;

	shost = dev_to_shost(dev->parent);
	if (!shost->transportt)
		return 0;
	if (shost->transportt->host_attrs.ac.class != &srp_host_class.class)
		return 0;

	i = to_srp_internal(shost->transportt);
	return &i->rport_attr_cont.ac == cont;
}

static int srp_host_match(struct attribute_container *cont, struct device *dev)
{
	struct Scsi_Host *shost;
	struct srp_internal *i;

	if (!scsi_is_host_device(dev))
		return 0;

	shost = dev_to_shost(dev);
	if (!shost->transportt)
		return 0;
	if (shost->transportt->host_attrs.ac.class != &srp_host_class.class)
		return 0;

	i = to_srp_internal(shost->transportt);
	return &i->t.host_attrs.ac == cont;
}

/**
 * srp_rport_add - add a SRP remote port to the device hierarchy
 * @shost:	scsi host the remote port is connected to.
 * @ids:	The port id for the remote port.
 *
 * Publishes a port to the rest of the system.
 */
struct srp_rport *srp_rport_add(struct Scsi_Host *shost,
				struct srp_rport_identifiers *ids)
{
	struct srp_rport *rport;
	struct device *parent = &shost->shost_gendev;
	int id, ret;

	rport = kzalloc(sizeof(*rport), GFP_KERNEL);
	if (!rport)
		return ERR_PTR(-ENOMEM);

	device_initialize(&rport->dev);

	rport->dev.parent = get_device(parent);
	rport->dev.release = srp_rport_release;

	memcpy(rport->port_id, ids->port_id, sizeof(rport->port_id));
	rport->roles = ids->roles;

	id = atomic_inc_return(&to_srp_host_attrs(shost)->next_port_id);
	dev_set_name(&rport->dev, "port-%d:%d", shost->host_no, id);

	transport_setup_device(&rport->dev);

	ret = device_add(&rport->dev);
	if (ret) {
		transport_destroy_device(&rport->dev);
		put_device(&rport->dev);
		return ERR_PTR(ret);
	}

	if (shost->active_mode & MODE_TARGET &&
	    ids->roles == SRP_RPORT_ROLE_INITIATOR) {
		ret = srp_tgt_it_nexus_create(shost, (unsigned long)rport,
					      rport->port_id);
		if (ret) {
			device_del(&rport->dev);
			transport_destroy_device(&rport->dev);
			put_device(&rport->dev);
			return ERR_PTR(ret);
		}
	}

	transport_add_device(&rport->dev);
	transport_configure_device(&rport->dev);

	return rport;
}
EXPORT_SYMBOL_GPL(srp_rport_add);

/**
 * srp_rport_del  -  remove a SRP remote port
 * @rport:	SRP remote port to remove
 *
 * Removes the specified SRP remote port.
 */
void srp_rport_del(struct srp_rport *rport)
{
	struct device *dev = &rport->dev;
	struct Scsi_Host *shost = dev_to_shost(dev->parent);

	if (shost->active_mode & MODE_TARGET &&
	    rport->roles == SRP_RPORT_ROLE_INITIATOR)
		srp_tgt_it_nexus_destroy(shost, (unsigned long)rport);

	transport_remove_device(dev);
	device_del(dev);
	transport_destroy_device(dev);
	put_device(dev);
}
EXPORT_SYMBOL_GPL(srp_rport_del);

static int do_srp_rport_del(struct device *dev, void *data)
{
	if (scsi_is_srp_rport(dev))
		srp_rport_del(dev_to_rport(dev));
	return 0;
}

/**
 * srp_remove_host  -  tear down a Scsi_Host's SRP data structures
 * @shost:	Scsi Host that is torn down
 *
 * Removes all SRP remote ports for a given Scsi_Host.
 * Must be called just before scsi_remove_host for SRP HBAs.
 */
void srp_remove_host(struct Scsi_Host *shost)
{
	device_for_each_child(&shost->shost_gendev, NULL, do_srp_rport_del);
}
EXPORT_SYMBOL_GPL(srp_remove_host);

static int srp_tsk_mgmt_response(struct Scsi_Host *shost, u64 nexus, u64 tm_id,
				 int result)
{
	struct srp_internal *i = to_srp_internal(shost->transportt);
	return i->f->tsk_mgmt_response(shost, nexus, tm_id, result);
}

static int srp_it_nexus_response(struct Scsi_Host *shost, u64 nexus, int result)
{
	struct srp_internal *i = to_srp_internal(shost->transportt);
	return i->f->it_nexus_response(shost, nexus, result);
}

/**
 * srp_attach_transport  -  instantiate SRP transport template
 * @ft:		SRP transport class function template
 */
struct scsi_transport_template *
srp_attach_transport(struct srp_function_template *ft)
{
	int count;
	struct srp_internal *i;

	i = kzalloc(sizeof(*i), GFP_KERNEL);
	if (!i)
		return NULL;

	i->t.tsk_mgmt_response = srp_tsk_mgmt_response;
	i->t.it_nexus_response = srp_it_nexus_response;

	i->t.host_size = sizeof(struct srp_host_attrs);
	i->t.host_attrs.ac.attrs = &i->host_attrs[0];
	i->t.host_attrs.ac.class = &srp_host_class.class;
	i->t.host_attrs.ac.match = srp_host_match;
	i->host_attrs[0] = NULL;
	transport_container_register(&i->t.host_attrs);

	i->rport_attr_cont.ac.attrs = &i->rport_attrs[0];
	i->rport_attr_cont.ac.class = &srp_rport_class.class;
	i->rport_attr_cont.ac.match = srp_rport_match;
	transport_container_register(&i->rport_attr_cont);

	count = 0;
	SETUP_RPORT_ATTRIBUTE_RD(port_id);
	SETUP_RPORT_ATTRIBUTE_RD(roles);
	i->rport_attrs[count] = NULL;

	i->f = ft;

	return &i->t;
}
EXPORT_SYMBOL_GPL(srp_attach_transport);

/**
 * srp_release_transport  -  release SRP transport template instance
 * @t:		transport template instance
 */
void srp_release_transport(struct scsi_transport_template *t)
{
	struct srp_internal *i = to_srp_internal(t);

	transport_container_unregister(&i->t.host_attrs);
	transport_container_unregister(&i->rport_attr_cont);

	kfree(i);
}
EXPORT_SYMBOL_GPL(srp_release_transport);

static __init int srp_transport_init(void)
{
	int ret;

	ret = transport_class_register(&srp_host_class);
	if (ret)
		return ret;
	ret = transport_class_register(&srp_rport_class);
	if (ret)
		goto unregister_host_class;

	return 0;
unregister_host_class:
	transport_class_unregister(&srp_host_class);
	return ret;
}

static void __exit srp_transport_exit(void)
{
	transport_class_unregister(&srp_host_class);
	transport_class_unregister(&srp_rport_class);
}

MODULE_AUTHOR("FUJITA Tomonori");
MODULE_DESCRIPTION("SRP Transport Attributes");
MODULE_LICENSE("GPL");

module_init(srp_transport_init);
module_exit(srp_transport_exit);