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 3 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 transport_container rport_attr_cont; 51 }; 52 53 #define to_srp_internal(tmpl) container_of(tmpl, struct srp_internal, t) 54 55 #define dev_to_rport(d) container_of(d, struct srp_rport, dev) 56 #define transport_class_to_srp_rport(dev) dev_to_rport((dev)->parent) 57 58 static int srp_host_setup(struct transport_container *tc, struct device *dev, 59 struct device *cdev) 60 { 61 struct Scsi_Host *shost = dev_to_shost(dev); 62 struct srp_host_attrs *srp_host = to_srp_host_attrs(shost); 63 64 atomic_set(&srp_host->next_port_id, 0); 65 return 0; 66 } 67 68 static DECLARE_TRANSPORT_CLASS(srp_host_class, "srp_host", srp_host_setup, 69 NULL, NULL); 70 71 static DECLARE_TRANSPORT_CLASS(srp_rport_class, "srp_remote_ports", 72 NULL, NULL, NULL); 73 74 #define SRP_PID(p) \ 75 (p)->port_id[0], (p)->port_id[1], (p)->port_id[2], (p)->port_id[3], \ 76 (p)->port_id[4], (p)->port_id[5], (p)->port_id[6], (p)->port_id[7], \ 77 (p)->port_id[8], (p)->port_id[9], (p)->port_id[10], (p)->port_id[11], \ 78 (p)->port_id[12], (p)->port_id[13], (p)->port_id[14], (p)->port_id[15] 79 80 #define SRP_PID_FMT "%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:" \ 81 "%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x" 82 83 static ssize_t 84 show_srp_rport_id(struct device *dev, struct device_attribute *attr, 85 char *buf) 86 { 87 struct srp_rport *rport = transport_class_to_srp_rport(dev); 88 return sprintf(buf, SRP_PID_FMT "\n", SRP_PID(rport)); 89 } 90 91 static DEVICE_ATTR(port_id, S_IRUGO, show_srp_rport_id, NULL); 92 93 static const struct { 94 u32 value; 95 char *name; 96 } srp_rport_role_names[] = { 97 {SRP_RPORT_ROLE_INITIATOR, "SRP Initiator"}, 98 {SRP_RPORT_ROLE_TARGET, "SRP Target"}, 99 }; 100 101 static ssize_t 102 show_srp_rport_roles(struct device *dev, struct device_attribute *attr, 103 char *buf) 104 { 105 struct srp_rport *rport = transport_class_to_srp_rport(dev); 106 int i; 107 char *name = NULL; 108 109 for (i = 0; i < ARRAY_SIZE(srp_rport_role_names); i++) 110 if (srp_rport_role_names[i].value == rport->roles) { 111 name = srp_rport_role_names[i].name; 112 break; 113 } 114 return sprintf(buf, "%s\n", name ? : "unknown"); 115 } 116 117 static DEVICE_ATTR(roles, S_IRUGO, show_srp_rport_roles, NULL); 118 119 static ssize_t store_srp_rport_delete(struct device *dev, 120 struct device_attribute *attr, 121 const char *buf, size_t count) 122 { 123 struct srp_rport *rport = transport_class_to_srp_rport(dev); 124 struct Scsi_Host *shost = dev_to_shost(dev); 125 struct srp_internal *i = to_srp_internal(shost->transportt); 126 127 if (i->f->rport_delete) { 128 i->f->rport_delete(rport); 129 return count; 130 } else { 131 return -ENOSYS; 132 } 133 } 134 135 static DEVICE_ATTR(delete, S_IWUSR, NULL, store_srp_rport_delete); 136 137 static void srp_rport_release(struct device *dev) 138 { 139 struct srp_rport *rport = dev_to_rport(dev); 140 141 put_device(dev->parent); 142 kfree(rport); 143 } 144 145 static int scsi_is_srp_rport(const struct device *dev) 146 { 147 return dev->release == srp_rport_release; 148 } 149 150 static int srp_rport_match(struct attribute_container *cont, 151 struct device *dev) 152 { 153 struct Scsi_Host *shost; 154 struct srp_internal *i; 155 156 if (!scsi_is_srp_rport(dev)) 157 return 0; 158 159 shost = dev_to_shost(dev->parent); 160 if (!shost->transportt) 161 return 0; 162 if (shost->transportt->host_attrs.ac.class != &srp_host_class.class) 163 return 0; 164 165 i = to_srp_internal(shost->transportt); 166 return &i->rport_attr_cont.ac == cont; 167 } 168 169 static int srp_host_match(struct attribute_container *cont, struct device *dev) 170 { 171 struct Scsi_Host *shost; 172 struct srp_internal *i; 173 174 if (!scsi_is_host_device(dev)) 175 return 0; 176 177 shost = dev_to_shost(dev); 178 if (!shost->transportt) 179 return 0; 180 if (shost->transportt->host_attrs.ac.class != &srp_host_class.class) 181 return 0; 182 183 i = to_srp_internal(shost->transportt); 184 return &i->t.host_attrs.ac == cont; 185 } 186 187 /** 188 * srp_rport_add - add a SRP remote port to the device hierarchy 189 * @shost: scsi host the remote port is connected to. 190 * @ids: The port id for the remote port. 191 * 192 * Publishes a port to the rest of the system. 193 */ 194 struct srp_rport *srp_rport_add(struct Scsi_Host *shost, 195 struct srp_rport_identifiers *ids) 196 { 197 struct srp_rport *rport; 198 struct device *parent = &shost->shost_gendev; 199 int id, ret; 200 201 rport = kzalloc(sizeof(*rport), GFP_KERNEL); 202 if (!rport) 203 return ERR_PTR(-ENOMEM); 204 205 device_initialize(&rport->dev); 206 207 rport->dev.parent = get_device(parent); 208 rport->dev.release = srp_rport_release; 209 210 memcpy(rport->port_id, ids->port_id, sizeof(rport->port_id)); 211 rport->roles = ids->roles; 212 213 id = atomic_inc_return(&to_srp_host_attrs(shost)->next_port_id); 214 dev_set_name(&rport->dev, "port-%d:%d", shost->host_no, id); 215 216 transport_setup_device(&rport->dev); 217 218 ret = device_add(&rport->dev); 219 if (ret) { 220 transport_destroy_device(&rport->dev); 221 put_device(&rport->dev); 222 return ERR_PTR(ret); 223 } 224 225 if (shost->active_mode & MODE_TARGET && 226 ids->roles == SRP_RPORT_ROLE_INITIATOR) { 227 ret = srp_tgt_it_nexus_create(shost, (unsigned long)rport, 228 rport->port_id); 229 if (ret) { 230 device_del(&rport->dev); 231 transport_destroy_device(&rport->dev); 232 put_device(&rport->dev); 233 return ERR_PTR(ret); 234 } 235 } 236 237 transport_add_device(&rport->dev); 238 transport_configure_device(&rport->dev); 239 240 return rport; 241 } 242 EXPORT_SYMBOL_GPL(srp_rport_add); 243 244 /** 245 * srp_rport_del - remove a SRP remote port 246 * @rport: SRP remote port to remove 247 * 248 * Removes the specified SRP remote port. 249 */ 250 void srp_rport_del(struct srp_rport *rport) 251 { 252 struct device *dev = &rport->dev; 253 struct Scsi_Host *shost = dev_to_shost(dev->parent); 254 255 if (shost->active_mode & MODE_TARGET && 256 rport->roles == SRP_RPORT_ROLE_INITIATOR) 257 srp_tgt_it_nexus_destroy(shost, (unsigned long)rport); 258 259 transport_remove_device(dev); 260 device_del(dev); 261 transport_destroy_device(dev); 262 put_device(dev); 263 } 264 EXPORT_SYMBOL_GPL(srp_rport_del); 265 266 static int do_srp_rport_del(struct device *dev, void *data) 267 { 268 if (scsi_is_srp_rport(dev)) 269 srp_rport_del(dev_to_rport(dev)); 270 return 0; 271 } 272 273 /** 274 * srp_remove_host - tear down a Scsi_Host's SRP data structures 275 * @shost: Scsi Host that is torn down 276 * 277 * Removes all SRP remote ports for a given Scsi_Host. 278 * Must be called just before scsi_remove_host for SRP HBAs. 279 */ 280 void srp_remove_host(struct Scsi_Host *shost) 281 { 282 device_for_each_child(&shost->shost_gendev, NULL, do_srp_rport_del); 283 } 284 EXPORT_SYMBOL_GPL(srp_remove_host); 285 286 static int srp_tsk_mgmt_response(struct Scsi_Host *shost, u64 nexus, u64 tm_id, 287 int result) 288 { 289 struct srp_internal *i = to_srp_internal(shost->transportt); 290 return i->f->tsk_mgmt_response(shost, nexus, tm_id, result); 291 } 292 293 static int srp_it_nexus_response(struct Scsi_Host *shost, u64 nexus, int result) 294 { 295 struct srp_internal *i = to_srp_internal(shost->transportt); 296 return i->f->it_nexus_response(shost, nexus, result); 297 } 298 299 /** 300 * srp_attach_transport - instantiate SRP transport template 301 * @ft: SRP transport class function template 302 */ 303 struct scsi_transport_template * 304 srp_attach_transport(struct srp_function_template *ft) 305 { 306 int count; 307 struct srp_internal *i; 308 309 i = kzalloc(sizeof(*i), GFP_KERNEL); 310 if (!i) 311 return NULL; 312 313 i->t.tsk_mgmt_response = srp_tsk_mgmt_response; 314 i->t.it_nexus_response = srp_it_nexus_response; 315 316 i->t.host_size = sizeof(struct srp_host_attrs); 317 i->t.host_attrs.ac.attrs = &i->host_attrs[0]; 318 i->t.host_attrs.ac.class = &srp_host_class.class; 319 i->t.host_attrs.ac.match = srp_host_match; 320 i->host_attrs[0] = NULL; 321 transport_container_register(&i->t.host_attrs); 322 323 i->rport_attr_cont.ac.attrs = &i->rport_attrs[0]; 324 i->rport_attr_cont.ac.class = &srp_rport_class.class; 325 i->rport_attr_cont.ac.match = srp_rport_match; 326 327 count = 0; 328 i->rport_attrs[count++] = &dev_attr_port_id; 329 i->rport_attrs[count++] = &dev_attr_roles; 330 if (ft->rport_delete) 331 i->rport_attrs[count++] = &dev_attr_delete; 332 i->rport_attrs[count++] = NULL; 333 BUG_ON(count > ARRAY_SIZE(i->rport_attrs)); 334 335 transport_container_register(&i->rport_attr_cont); 336 337 i->f = ft; 338 339 return &i->t; 340 } 341 EXPORT_SYMBOL_GPL(srp_attach_transport); 342 343 /** 344 * srp_release_transport - release SRP transport template instance 345 * @t: transport template instance 346 */ 347 void srp_release_transport(struct scsi_transport_template *t) 348 { 349 struct srp_internal *i = to_srp_internal(t); 350 351 transport_container_unregister(&i->t.host_attrs); 352 transport_container_unregister(&i->rport_attr_cont); 353 354 kfree(i); 355 } 356 EXPORT_SYMBOL_GPL(srp_release_transport); 357 358 static __init int srp_transport_init(void) 359 { 360 int ret; 361 362 ret = transport_class_register(&srp_host_class); 363 if (ret) 364 return ret; 365 ret = transport_class_register(&srp_rport_class); 366 if (ret) 367 goto unregister_host_class; 368 369 return 0; 370 unregister_host_class: 371 transport_class_unregister(&srp_host_class); 372 return ret; 373 } 374 375 static void __exit srp_transport_exit(void) 376 { 377 transport_class_unregister(&srp_host_class); 378 transport_class_unregister(&srp_rport_class); 379 } 380 381 MODULE_AUTHOR("FUJITA Tomonori"); 382 MODULE_DESCRIPTION("SRP Transport Attributes"); 383 MODULE_LICENSE("GPL"); 384 385 module_init(srp_transport_init); 386 module_exit(srp_transport_exit); 387