[SCSI] ses: add subenclosure support
[linux-2.6.git] / drivers / scsi / scsi_transport_srp.c
1 /*
2  * SCSI RDMA (SRP) transport class
3  *
4  * Copyright (C) 2007 FUJITA Tomonori <tomof@acm.org>
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License as
8  * published by the Free Software Foundation, version 2 of the
9  * License.
10  *
11  * This program is distributed in the hope that it will be useful, but
12  * WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * 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
18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
19  * 02110-1301 USA
20  */
21 #include <linux/init.h>
22 #include <linux/module.h>
23 #include <linux/jiffies.h>
24 #include <linux/err.h>
25 #include <linux/slab.h>
26 #include <linux/string.h>
27
28 #include <scsi/scsi.h>
29 #include <scsi/scsi_device.h>
30 #include <scsi/scsi_host.h>
31 #include <scsi/scsi_transport.h>
32 #include <scsi/scsi_transport_srp.h>
33 #include "scsi_transport_srp_internal.h"
34
35 struct srp_host_attrs {
36         atomic_t next_port_id;
37 };
38 #define to_srp_host_attrs(host) ((struct srp_host_attrs *)(host)->shost_data)
39
40 #define SRP_HOST_ATTRS 0
41 #define SRP_RPORT_ATTRS 2
42
43 struct srp_internal {
44         struct scsi_transport_template t;
45         struct srp_function_template *f;
46
47         struct device_attribute *host_attrs[SRP_HOST_ATTRS + 1];
48
49         struct device_attribute *rport_attrs[SRP_RPORT_ATTRS + 1];
50         struct device_attribute private_rport_attrs[SRP_RPORT_ATTRS];
51         struct transport_container rport_attr_cont;
52 };
53
54 #define to_srp_internal(tmpl) container_of(tmpl, struct srp_internal, t)
55
56 #define dev_to_rport(d) container_of(d, struct srp_rport, dev)
57 #define transport_class_to_srp_rport(dev) dev_to_rport((dev)->parent)
58
59 static int srp_host_setup(struct transport_container *tc, struct device *dev,
60                           struct device *cdev)
61 {
62         struct Scsi_Host *shost = dev_to_shost(dev);
63         struct srp_host_attrs *srp_host = to_srp_host_attrs(shost);
64
65         atomic_set(&srp_host->next_port_id, 0);
66         return 0;
67 }
68
69 static DECLARE_TRANSPORT_CLASS(srp_host_class, "srp_host", srp_host_setup,
70                                NULL, NULL);
71
72 static DECLARE_TRANSPORT_CLASS(srp_rport_class, "srp_remote_ports",
73                                NULL, NULL, NULL);
74
75 #define SETUP_TEMPLATE(attrb, field, perm, test, ro_test, ro_perm)      \
76         i->private_##attrb[count] = dev_attr_##field;           \
77         i->private_##attrb[count].attr.mode = perm;                     \
78         if (ro_test) {                                                  \
79                 i->private_##attrb[count].attr.mode = ro_perm;          \
80                 i->private_##attrb[count].store = NULL;                 \
81         }                                                               \
82         i->attrb[count] = &i->private_##attrb[count];                   \
83         if (test)                                                       \
84                 count++
85
86 #define SETUP_RPORT_ATTRIBUTE_RD(field)                                 \
87         SETUP_TEMPLATE(rport_attrs, field, S_IRUGO, 1, 0, 0)
88
89 #define SETUP_RPORT_ATTRIBUTE_RW(field)                                 \
90         SETUP_TEMPLATE(rport_attrs, field, S_IRUGO | S_IWUSR,           \
91                        1, 1, S_IRUGO)
92
93 #define SRP_PID(p) \
94         (p)->port_id[0], (p)->port_id[1], (p)->port_id[2], (p)->port_id[3], \
95         (p)->port_id[4], (p)->port_id[5], (p)->port_id[6], (p)->port_id[7], \
96         (p)->port_id[8], (p)->port_id[9], (p)->port_id[10], (p)->port_id[11], \
97         (p)->port_id[12], (p)->port_id[13], (p)->port_id[14], (p)->port_id[15]
98
99 #define SRP_PID_FMT "%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:" \
100         "%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x"
101
102 static ssize_t
103 show_srp_rport_id(struct device *dev, struct device_attribute *attr,
104                   char *buf)
105 {
106         struct srp_rport *rport = transport_class_to_srp_rport(dev);
107         return sprintf(buf, SRP_PID_FMT "\n", SRP_PID(rport));
108 }
109
110 static DEVICE_ATTR(port_id, S_IRUGO, show_srp_rport_id, NULL);
111
112 static const struct {
113         u32 value;
114         char *name;
115 } srp_rport_role_names[] = {
116         {SRP_RPORT_ROLE_INITIATOR, "SRP Initiator"},
117         {SRP_RPORT_ROLE_TARGET, "SRP Target"},
118 };
119
120 static ssize_t
121 show_srp_rport_roles(struct device *dev, struct device_attribute *attr,
122                      char *buf)
123 {
124         struct srp_rport *rport = transport_class_to_srp_rport(dev);
125         int i;
126         char *name = NULL;
127
128         for (i = 0; i < ARRAY_SIZE(srp_rport_role_names); i++)
129                 if (srp_rport_role_names[i].value == rport->roles) {
130                         name = srp_rport_role_names[i].name;
131                         break;
132                 }
133         return sprintf(buf, "%s\n", name ? : "unknown");
134 }
135
136 static DEVICE_ATTR(roles, S_IRUGO, show_srp_rport_roles, NULL);
137
138 static void srp_rport_release(struct device *dev)
139 {
140         struct srp_rport *rport = dev_to_rport(dev);
141
142         put_device(dev->parent);
143         kfree(rport);
144 }
145
146 static int scsi_is_srp_rport(const struct device *dev)
147 {
148         return dev->release == srp_rport_release;
149 }
150
151 static int srp_rport_match(struct attribute_container *cont,
152                            struct device *dev)
153 {
154         struct Scsi_Host *shost;
155         struct srp_internal *i;
156
157         if (!scsi_is_srp_rport(dev))
158                 return 0;
159
160         shost = dev_to_shost(dev->parent);
161         if (!shost->transportt)
162                 return 0;
163         if (shost->transportt->host_attrs.ac.class != &srp_host_class.class)
164                 return 0;
165
166         i = to_srp_internal(shost->transportt);
167         return &i->rport_attr_cont.ac == cont;
168 }
169
170 static int srp_host_match(struct attribute_container *cont, struct device *dev)
171 {
172         struct Scsi_Host *shost;
173         struct srp_internal *i;
174
175         if (!scsi_is_host_device(dev))
176                 return 0;
177
178         shost = dev_to_shost(dev);
179         if (!shost->transportt)
180                 return 0;
181         if (shost->transportt->host_attrs.ac.class != &srp_host_class.class)
182                 return 0;
183
184         i = to_srp_internal(shost->transportt);
185         return &i->t.host_attrs.ac == cont;
186 }
187
188 /**
189  * srp_rport_add - add a SRP remote port to the device hierarchy
190  * @shost:      scsi host the remote port is connected to.
191  * @ids:        The port id for the remote port.
192  *
193  * Publishes a port to the rest of the system.
194  */
195 struct srp_rport *srp_rport_add(struct Scsi_Host *shost,
196                                 struct srp_rport_identifiers *ids)
197 {
198         struct srp_rport *rport;
199         struct device *parent = &shost->shost_gendev;
200         int id, ret;
201
202         rport = kzalloc(sizeof(*rport), GFP_KERNEL);
203         if (!rport)
204                 return ERR_PTR(-ENOMEM);
205
206         device_initialize(&rport->dev);
207
208         rport->dev.parent = get_device(parent);
209         rport->dev.release = srp_rport_release;
210
211         memcpy(rport->port_id, ids->port_id, sizeof(rport->port_id));
212         rport->roles = ids->roles;
213
214         id = atomic_inc_return(&to_srp_host_attrs(shost)->next_port_id);
215         dev_set_name(&rport->dev, "port-%d:%d", shost->host_no, id);
216
217         transport_setup_device(&rport->dev);
218
219         ret = device_add(&rport->dev);
220         if (ret) {
221                 transport_destroy_device(&rport->dev);
222                 put_device(&rport->dev);
223                 return ERR_PTR(ret);
224         }
225
226         if (shost->active_mode & MODE_TARGET &&
227             ids->roles == SRP_RPORT_ROLE_INITIATOR) {
228                 ret = srp_tgt_it_nexus_create(shost, (unsigned long)rport,
229                                               rport->port_id);
230                 if (ret) {
231                         device_del(&rport->dev);
232                         transport_destroy_device(&rport->dev);
233                         put_device(&rport->dev);
234                         return ERR_PTR(ret);
235                 }
236         }
237
238         transport_add_device(&rport->dev);
239         transport_configure_device(&rport->dev);
240
241         return rport;
242 }
243 EXPORT_SYMBOL_GPL(srp_rport_add);
244
245 /**
246  * srp_rport_del  -  remove a SRP remote port
247  * @rport:      SRP remote port to remove
248  *
249  * Removes the specified SRP remote port.
250  */
251 void srp_rport_del(struct srp_rport *rport)
252 {
253         struct device *dev = &rport->dev;
254         struct Scsi_Host *shost = dev_to_shost(dev->parent);
255
256         if (shost->active_mode & MODE_TARGET &&
257             rport->roles == SRP_RPORT_ROLE_INITIATOR)
258                 srp_tgt_it_nexus_destroy(shost, (unsigned long)rport);
259
260         transport_remove_device(dev);
261         device_del(dev);
262         transport_destroy_device(dev);
263         put_device(dev);
264 }
265 EXPORT_SYMBOL_GPL(srp_rport_del);
266
267 static int do_srp_rport_del(struct device *dev, void *data)
268 {
269         if (scsi_is_srp_rport(dev))
270                 srp_rport_del(dev_to_rport(dev));
271         return 0;
272 }
273
274 /**
275  * srp_remove_host  -  tear down a Scsi_Host's SRP data structures
276  * @shost:      Scsi Host that is torn down
277  *
278  * Removes all SRP remote ports for a given Scsi_Host.
279  * Must be called just before scsi_remove_host for SRP HBAs.
280  */
281 void srp_remove_host(struct Scsi_Host *shost)
282 {
283         device_for_each_child(&shost->shost_gendev, NULL, do_srp_rport_del);
284 }
285 EXPORT_SYMBOL_GPL(srp_remove_host);
286
287 static int srp_tsk_mgmt_response(struct Scsi_Host *shost, u64 nexus, u64 tm_id,
288                                  int result)
289 {
290         struct srp_internal *i = to_srp_internal(shost->transportt);
291         return i->f->tsk_mgmt_response(shost, nexus, tm_id, result);
292 }
293
294 static int srp_it_nexus_response(struct Scsi_Host *shost, u64 nexus, int result)
295 {
296         struct srp_internal *i = to_srp_internal(shost->transportt);
297         return i->f->it_nexus_response(shost, nexus, result);
298 }
299
300 /**
301  * srp_attach_transport  -  instantiate SRP transport template
302  * @ft:         SRP transport class function template
303  */
304 struct scsi_transport_template *
305 srp_attach_transport(struct srp_function_template *ft)
306 {
307         int count;
308         struct srp_internal *i;
309
310         i = kzalloc(sizeof(*i), GFP_KERNEL);
311         if (!i)
312                 return NULL;
313
314         i->t.tsk_mgmt_response = srp_tsk_mgmt_response;
315         i->t.it_nexus_response = srp_it_nexus_response;
316
317         i->t.host_size = sizeof(struct srp_host_attrs);
318         i->t.host_attrs.ac.attrs = &i->host_attrs[0];
319         i->t.host_attrs.ac.class = &srp_host_class.class;
320         i->t.host_attrs.ac.match = srp_host_match;
321         i->host_attrs[0] = NULL;
322         transport_container_register(&i->t.host_attrs);
323
324         i->rport_attr_cont.ac.attrs = &i->rport_attrs[0];
325         i->rport_attr_cont.ac.class = &srp_rport_class.class;
326         i->rport_attr_cont.ac.match = srp_rport_match;
327         transport_container_register(&i->rport_attr_cont);
328
329         count = 0;
330         SETUP_RPORT_ATTRIBUTE_RD(port_id);
331         SETUP_RPORT_ATTRIBUTE_RD(roles);
332         i->rport_attrs[count] = NULL;
333
334         i->f = ft;
335
336         return &i->t;
337 }
338 EXPORT_SYMBOL_GPL(srp_attach_transport);
339
340 /**
341  * srp_release_transport  -  release SRP transport template instance
342  * @t:          transport template instance
343  */
344 void srp_release_transport(struct scsi_transport_template *t)
345 {
346         struct srp_internal *i = to_srp_internal(t);
347
348         transport_container_unregister(&i->t.host_attrs);
349         transport_container_unregister(&i->rport_attr_cont);
350
351         kfree(i);
352 }
353 EXPORT_SYMBOL_GPL(srp_release_transport);
354
355 static __init int srp_transport_init(void)
356 {
357         int ret;
358
359         ret = transport_class_register(&srp_host_class);
360         if (ret)
361                 return ret;
362         ret = transport_class_register(&srp_rport_class);
363         if (ret)
364                 goto unregister_host_class;
365
366         return 0;
367 unregister_host_class:
368         transport_class_unregister(&srp_host_class);
369         return ret;
370 }
371
372 static void __exit srp_transport_exit(void)
373 {
374         transport_class_unregister(&srp_host_class);
375         transport_class_unregister(&srp_rport_class);
376 }
377
378 MODULE_AUTHOR("FUJITA Tomonori");
379 MODULE_DESCRIPTION("SRP Transport Attributes");
380 MODULE_LICENSE("GPL");
381
382 module_init(srp_transport_init);
383 module_exit(srp_transport_exit);