x86, delay: tsc based udelay should have rdtsc_barrier
[linux-2.6/mini2440.git] / drivers / scsi / scsi_transport_srp.c
blob21a045e0559ff7ad9a209742f55b020b99adcb6b
1 /*
2 * SCSI RDMA (SRP) transport class
4 * Copyright (C) 2007 FUJITA Tomonori <tomof@acm.org>
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.
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.
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
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>
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"
35 struct srp_host_attrs {
36 atomic_t next_port_id;
38 #define to_srp_host_attrs(host) ((struct srp_host_attrs *)(host)->shost_data)
40 #define SRP_HOST_ATTRS 0
41 #define SRP_RPORT_ATTRS 2
43 struct srp_internal {
44 struct scsi_transport_template t;
45 struct srp_function_template *f;
47 struct device_attribute *host_attrs[SRP_HOST_ATTRS + 1];
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;
54 #define to_srp_internal(tmpl) container_of(tmpl, struct srp_internal, t)
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)
59 static int srp_host_setup(struct transport_container *tc, struct device *dev,
60 struct device *cdev)
62 struct Scsi_Host *shost = dev_to_shost(dev);
63 struct srp_host_attrs *srp_host = to_srp_host_attrs(shost);
65 atomic_set(&srp_host->next_port_id, 0);
66 return 0;
69 static DECLARE_TRANSPORT_CLASS(srp_host_class, "srp_host", srp_host_setup,
70 NULL, NULL);
72 static DECLARE_TRANSPORT_CLASS(srp_rport_class, "srp_remote_ports",
73 NULL, NULL, NULL);
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++
86 #define SETUP_RPORT_ATTRIBUTE_RD(field) \
87 SETUP_TEMPLATE(rport_attrs, field, S_IRUGO, 1, 0, 0)
89 #define SETUP_RPORT_ATTRIBUTE_RW(field) \
90 SETUP_TEMPLATE(rport_attrs, field, S_IRUGO | S_IWUSR, \
91 1, 1, S_IRUGO)
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]
99 #define SRP_PID_FMT "%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:" \
100 "%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x"
102 static ssize_t
103 show_srp_rport_id(struct device *dev, struct device_attribute *attr,
104 char *buf)
106 struct srp_rport *rport = transport_class_to_srp_rport(dev);
107 return sprintf(buf, SRP_PID_FMT "\n", SRP_PID(rport));
110 static DEVICE_ATTR(port_id, S_IRUGO, show_srp_rport_id, NULL);
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"},
120 static ssize_t
121 show_srp_rport_roles(struct device *dev, struct device_attribute *attr,
122 char *buf)
124 struct srp_rport *rport = transport_class_to_srp_rport(dev);
125 int i;
126 char *name = NULL;
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;
133 return sprintf(buf, "%s\n", name ? : "unknown");
136 static DEVICE_ATTR(roles, S_IRUGO, show_srp_rport_roles, NULL);
138 static void srp_rport_release(struct device *dev)
140 struct srp_rport *rport = dev_to_rport(dev);
142 put_device(dev->parent);
143 kfree(rport);
146 static int scsi_is_srp_rport(const struct device *dev)
148 return dev->release == srp_rport_release;
151 static int srp_rport_match(struct attribute_container *cont,
152 struct device *dev)
154 struct Scsi_Host *shost;
155 struct srp_internal *i;
157 if (!scsi_is_srp_rport(dev))
158 return 0;
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;
166 i = to_srp_internal(shost->transportt);
167 return &i->rport_attr_cont.ac == cont;
170 static int srp_host_match(struct attribute_container *cont, struct device *dev)
172 struct Scsi_Host *shost;
173 struct srp_internal *i;
175 if (!scsi_is_host_device(dev))
176 return 0;
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;
184 i = to_srp_internal(shost->transportt);
185 return &i->t.host_attrs.ac == cont;
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.
193 * Publishes a port to the rest of the system.
195 struct srp_rport *srp_rport_add(struct Scsi_Host *shost,
196 struct srp_rport_identifiers *ids)
198 struct srp_rport *rport;
199 struct device *parent = &shost->shost_gendev;
200 int id, ret;
202 rport = kzalloc(sizeof(*rport), GFP_KERNEL);
203 if (!rport)
204 return ERR_PTR(-ENOMEM);
206 device_initialize(&rport->dev);
208 rport->dev.parent = get_device(parent);
209 rport->dev.release = srp_rport_release;
211 memcpy(rport->port_id, ids->port_id, sizeof(rport->port_id));
212 rport->roles = ids->roles;
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);
217 transport_setup_device(&rport->dev);
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);
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);
238 transport_add_device(&rport->dev);
239 transport_configure_device(&rport->dev);
241 return rport;
243 EXPORT_SYMBOL_GPL(srp_rport_add);
246 * srp_rport_del - remove a SRP remote port
247 * @rport: SRP remote port to remove
249 * Removes the specified SRP remote port.
251 void srp_rport_del(struct srp_rport *rport)
253 struct device *dev = &rport->dev;
254 struct Scsi_Host *shost = dev_to_shost(dev->parent);
256 if (shost->active_mode & MODE_TARGET &&
257 rport->roles == SRP_RPORT_ROLE_INITIATOR)
258 srp_tgt_it_nexus_destroy(shost, (unsigned long)rport);
260 transport_remove_device(dev);
261 device_del(dev);
262 transport_destroy_device(dev);
263 put_device(dev);
265 EXPORT_SYMBOL_GPL(srp_rport_del);
267 static int do_srp_rport_del(struct device *dev, void *data)
269 if (scsi_is_srp_rport(dev))
270 srp_rport_del(dev_to_rport(dev));
271 return 0;
275 * srp_remove_host - tear down a Scsi_Host's SRP data structures
276 * @shost: Scsi Host that is torn down
278 * Removes all SRP remote ports for a given Scsi_Host.
279 * Must be called just before scsi_remove_host for SRP HBAs.
281 void srp_remove_host(struct Scsi_Host *shost)
283 device_for_each_child(&shost->shost_gendev, NULL, do_srp_rport_del);
285 EXPORT_SYMBOL_GPL(srp_remove_host);
287 static int srp_tsk_mgmt_response(struct Scsi_Host *shost, u64 nexus, u64 tm_id,
288 int result)
290 struct srp_internal *i = to_srp_internal(shost->transportt);
291 return i->f->tsk_mgmt_response(shost, nexus, tm_id, result);
294 static int srp_it_nexus_response(struct Scsi_Host *shost, u64 nexus, int result)
296 struct srp_internal *i = to_srp_internal(shost->transportt);
297 return i->f->it_nexus_response(shost, nexus, result);
301 * srp_attach_transport - instantiate SRP transport template
302 * @ft: SRP transport class function template
304 struct scsi_transport_template *
305 srp_attach_transport(struct srp_function_template *ft)
307 int count;
308 struct srp_internal *i;
310 i = kzalloc(sizeof(*i), GFP_KERNEL);
311 if (!i)
312 return NULL;
314 i->t.tsk_mgmt_response = srp_tsk_mgmt_response;
315 i->t.it_nexus_response = srp_it_nexus_response;
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);
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);
329 count = 0;
330 SETUP_RPORT_ATTRIBUTE_RD(port_id);
331 SETUP_RPORT_ATTRIBUTE_RD(roles);
332 i->rport_attrs[count] = NULL;
334 i->f = ft;
336 return &i->t;
338 EXPORT_SYMBOL_GPL(srp_attach_transport);
341 * srp_release_transport - release SRP transport template instance
342 * @t: transport template instance
344 void srp_release_transport(struct scsi_transport_template *t)
346 struct srp_internal *i = to_srp_internal(t);
348 transport_container_unregister(&i->t.host_attrs);
349 transport_container_unregister(&i->rport_attr_cont);
351 kfree(i);
353 EXPORT_SYMBOL_GPL(srp_release_transport);
355 static __init int srp_transport_init(void)
357 int ret;
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;
366 return 0;
367 unregister_host_class:
368 transport_class_unregister(&srp_host_class);
369 return ret;
372 static void __exit srp_transport_exit(void)
374 transport_class_unregister(&srp_host_class);
375 transport_class_unregister(&srp_rport_class);
378 MODULE_AUTHOR("FUJITA Tomonori");
379 MODULE_DESCRIPTION("SRP Transport Attributes");
380 MODULE_LICENSE("GPL");
382 module_init(srp_transport_init);
383 module_exit(srp_transport_exit);