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); 384