drivers/scsi/libsas/sas_discover.c

   1 /*
   2  * Serial Attached SCSI (SAS) Discover process
   3  *
   4  * Copyright (C) 2005 Adaptec, Inc.  All rights reserved.
   5  * Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com>
   6  *
   7  * This file is licensed under GPLv2.
   8  *
   9  * This program is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU General Public License as
  11  * published by the Free Software Foundation; either version 2 of the
  12  * License, or (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful, but
  15  * WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  22  *
  23  */
  24
  25 #include <linux/scatterlist.h>
  26 #include <linux/slab.h>
  27 #include <scsi/scsi_host.h>
  28 #include <scsi/scsi_eh.h>
  29 #include "sas_internal.h"
  30
  31 #include <scsi/scsi_transport.h>
  32 #include <scsi/scsi_transport_sas.h>
  33 #include <scsi/sas_ata.h>
  34 #include "../scsi_sas_internal.h"
  35
  36 /* ---------- Basic task processing for discovery purposes ---------- */
  37
  38 void sas_init_dev(struct domain_device *dev)
  39 {
  40         switch (dev->dev_type) {
  41         case SAS_END_DEV:
  42                 INIT_LIST_HEAD(&dev->ssp_dev.eh_list_node);
  43                 break;
  44         case EDGE_DEV:
  45         case FANOUT_DEV:
  46                 INIT_LIST_HEAD(&dev->ex_dev.children);
  47                 mutex_init(&dev->ex_dev.cmd_mutex);
  48                 break;
  49         case SATA_DEV:
  50         case SATA_PM:
  51         case SATA_PM_PORT:
  52         case SATA_PENDING:
  53                 INIT_LIST_HEAD(&dev->sata_dev.children);
  54                 break;
  55         default:
  56                 break;
  57         }
  58 }
  59
  60 /* ---------- Domain device discovery ---------- */
  61
  62 /**
  63  * sas_get_port_device -- Discover devices which caused port creation
  64  * @port: pointer to struct sas_port of interest
  65  *
  66  * Devices directly attached to a HA port, have no parent.  This is
  67  * how we know they are (domain) "root" devices.  All other devices
  68  * do, and should have their "parent" pointer set appropriately as
  69  * soon as a child device is discovered.
  70  */
  71 static int sas_get_port_device(struct asd_sas_port *port)
  72 {
  73         struct asd_sas_phy *phy;
  74         struct sas_rphy *rphy;
  75         struct domain_device *dev;
  76         int rc = -ENODEV;
  77
  78         dev = sas_alloc_device();
  79         if (!dev)
  80                 return -ENOMEM;
  81
  82         spin_lock_irq(&port->phy_list_lock);
  83         if (list_empty(&port->phy_list)) {
  84                 spin_unlock_irq(&port->phy_list_lock);
  85                 sas_put_device(dev);
  86                 return -ENODEV;
  87         }
  88         phy = container_of(port->phy_list.next, struct asd_sas_phy, port_phy_el);
  89         spin_lock(&phy->frame_rcvd_lock);
  90         memcpy(dev->frame_rcvd, phy->frame_rcvd, min(sizeof(dev->frame_rcvd),
  91                                              (size_t)phy->frame_rcvd_size));
  92         spin_unlock(&phy->frame_rcvd_lock);
  93         spin_unlock_irq(&port->phy_list_lock);
  94
  95         if (dev->frame_rcvd[0] == 0x34 && port->oob_mode == SATA_OOB_MODE) {
  96                 struct dev_to_host_fis *fis =
  97                         (struct dev_to_host_fis *) dev->frame_rcvd;
  98                 if (fis->interrupt_reason == 1 && fis->lbal == 1 &&
  99                     fis->byte_count_low==0x69 && fis->byte_count_high == 0x96
 100                     && (fis->device & ~0x10) == 0)
 101                         dev->dev_type = SATA_PM;
 102                 else
 103                         dev->dev_type = SATA_DEV;
 104                 dev->tproto = SAS_PROTOCOL_SATA;
 105         } else {
 106                 struct sas_identify_frame *id =
 107                         (struct sas_identify_frame *) dev->frame_rcvd;
 108                 dev->dev_type = id->dev_type;
 109                 dev->iproto = id->initiator_bits;
 110                 dev->tproto = id->target_bits;
 111         }
 112
 113         sas_init_dev(dev);
 114
 115         dev->port = port;
 116         switch (dev->dev_type) {
 117         case SATA_DEV:
 118                 rc = sas_ata_init(dev);
 119                 if (rc) {
 120                         rphy = NULL;
 121                         break;
 122                 }
 123                 /* fall through */
 124         case SAS_END_DEV:
 125                 rphy = sas_end_device_alloc(port->port);
 126                 break;
 127         case EDGE_DEV:
 128                 rphy = sas_expander_alloc(port->port,
 129                                           SAS_EDGE_EXPANDER_DEVICE);
 130                 break;
 131         case FANOUT_DEV:
 132                 rphy = sas_expander_alloc(port->port,
 133                                           SAS_FANOUT_EXPANDER_DEVICE);
 134                 break;
 135         default:
 136                 printk("ERROR: Unidentified device type %d\n", dev->dev_type);
 137                 rphy = NULL;
 138                 break;
 139         }
 140
 141         if (!rphy) {
 142                 sas_put_device(dev);
 143                 return rc;
 144         }
 145
 146         rphy->identify.phy_identifier = phy->phy->identify.phy_identifier;
 147         memcpy(dev->sas_addr, port->attached_sas_addr, SAS_ADDR_SIZE);
 148         sas_fill_in_rphy(dev, rphy);
 149         sas_hash_addr(dev->hashed_sas_addr, dev->sas_addr);
 150         port->port_dev = dev;
 151         dev->linkrate = port->linkrate;
 152         dev->min_linkrate = port->linkrate;
 153         dev->max_linkrate = port->linkrate;
 154         dev->pathways = port->num_phys;
 155         memset(port->disc.fanout_sas_addr, 0, SAS_ADDR_SIZE);
 156         memset(port->disc.eeds_a, 0, SAS_ADDR_SIZE);
 157         memset(port->disc.eeds_b, 0, SAS_ADDR_SIZE);
 158         port->disc.max_level = 0;
 159         sas_device_set_phy(dev, port->port);
 160
 161         dev->rphy = rphy;
 162         get_device(&dev->rphy->dev);
 163
 164         if (dev_is_sata(dev) || dev->dev_type == SAS_END_DEV)
 165                 list_add_tail(&dev->disco_list_node, &port->disco_list);
 166         else {
 167                 spin_lock_irq(&port->dev_list_lock);
 168                 list_add_tail(&dev->dev_list_node, &port->dev_list);
 169                 spin_unlock_irq(&port->dev_list_lock);
 170         }
 171
 172         spin_lock_irq(&port->phy_list_lock);
 173         list_for_each_entry(phy, &port->phy_list, port_phy_el)
 174                 sas_phy_set_target(phy, dev);
 175         spin_unlock_irq(&port->phy_list_lock);
 176
 177         return 0;
 178 }
 179
 180 /* ---------- Discover and Revalidate ---------- */
 181
 182 int sas_notify_lldd_dev_found(struct domain_device *dev)
 183 {
 184         int res = 0;
 185         struct sas_ha_struct *sas_ha = dev->port->ha;
 186         struct Scsi_Host *shost = sas_ha->core.shost;
 187         struct sas_internal *i = to_sas_internal(shost->transportt);
 188
 189         if (i->dft->lldd_dev_found) {
 190                 res = i->dft->lldd_dev_found(dev);
 191                 if (res) {
 192                         printk("sas: driver on pcidev %s cannot handle "
 193                                "device %llx, error:%d\n",
 194                                dev_name(sas_ha->dev),
 195                                SAS_ADDR(dev->sas_addr), res);
 196                 }
 197                 kref_get(&dev->kref);
 198         }
 199         return res;
 200 }
 201
 202
 203 void sas_notify_lldd_dev_gone(struct domain_device *dev)
 204 {
 205         struct sas_ha_struct *sas_ha = dev->port->ha;
 206         struct Scsi_Host *shost = sas_ha->core.shost;
 207         struct sas_internal *i = to_sas_internal(shost->transportt);
 208
 209         if (i->dft->lldd_dev_gone) {
 210                 i->dft->lldd_dev_gone(dev);
 211                 sas_put_device(dev);
 212         }
 213 }
 214
 215 static void sas_probe_devices(struct work_struct *work)
 216 {
 217         struct domain_device *dev, *n;
 218         struct sas_discovery_event *ev = to_sas_discovery_event(work);
 219         struct asd_sas_port *port = ev->port;
 220
 221         clear_bit(DISCE_PROBE, &port->disc.pending);
 222
 223         /* devices must be domain members before link recovery and probe */
 224         list_for_each_entry(dev, &port->disco_list, disco_list_node) {
 225                 spin_lock_irq(&port->dev_list_lock);
 226                 list_add_tail(&dev->dev_list_node, &port->dev_list);
 227                 spin_unlock_irq(&port->dev_list_lock);
 228         }
 229
 230         sas_probe_sata(port);
 231
 232         list_for_each_entry_safe(dev, n, &port->disco_list, disco_list_node) {
 233                 int err;
 234
 235                 err = sas_rphy_add(dev->rphy);
 236                 if (err)
 237                         sas_fail_probe(dev, __func__, err);
 238                 else
 239                         list_del_init(&dev->disco_list_node);
 240         }
 241 }
 242
 243 /**
 244  * sas_discover_end_dev -- discover an end device (SSP, etc)
 245  * @end: pointer to domain device of interest
 246  *
 247  * See comment in sas_discover_sata().
 248  */
 249 int sas_discover_end_dev(struct domain_device *dev)
 250 {
 251         int res;
 252
 253         res = sas_notify_lldd_dev_found(dev);
 254         if (res)
 255                 return res;
 256         sas_discover_event(dev->port, DISCE_PROBE);
 257
 258         return 0;
 259 }
 260
 261 /* ---------- Device registration and unregistration ---------- */
 262
 263 void sas_free_device(struct kref *kref)
 264 {
 265         struct domain_device *dev = container_of(kref, typeof(*dev), kref);
 266
 267         put_device(&dev->rphy->dev);
 268         dev->rphy = NULL;
 269
 270         if (dev->parent)
 271                 sas_put_device(dev->parent);
 272
 273         sas_port_put_phy(dev->phy);
 274         dev->phy = NULL;
 275
 276         /* remove the phys and ports, everything else should be gone */
 277         if (dev->dev_type == EDGE_DEV || dev->dev_type == FANOUT_DEV)
 278                 kfree(dev->ex_dev.ex_phy);
 279
 280         if (dev_is_sata(dev) && dev->sata_dev.ap) {
 281                 ata_sas_port_destroy(dev->sata_dev.ap);
 282                 dev->sata_dev.ap = NULL;
 283         }
 284
 285         kfree(dev);
 286 }
 287
 288 static void sas_unregister_common_dev(struct asd_sas_port *port, struct domain_device *dev)
 289 {
 290         struct sas_ha_struct *ha = port->ha;
 291
 292         sas_notify_lldd_dev_gone(dev);
 293         if (!dev->parent)
 294                 dev->port->port_dev = NULL;
 295         else
 296                 list_del_init(&dev->siblings);
 297
 298         spin_lock_irq(&port->dev_list_lock);
 299         list_del_init(&dev->dev_list_node);
 300         if (dev_is_sata(dev))
 301                 sas_ata_end_eh(dev->sata_dev.ap);
 302         spin_unlock_irq(&port->dev_list_lock);
 303
 304         spin_lock_irq(&ha->lock);
 305         if (dev->dev_type == SAS_END_DEV &&
 306             !list_empty(&dev->ssp_dev.eh_list_node)) {
 307                 list_del_init(&dev->ssp_dev.eh_list_node);
 308                 ha->eh_active--;
 309         }
 310         spin_unlock_irq(&ha->lock);
 311
 312         sas_put_device(dev);
 313 }
 314
 315 static void sas_destruct_devices(struct work_struct *work)
 316 {
 317         struct domain_device *dev, *n;
 318         struct sas_discovery_event *ev = to_sas_discovery_event(work);
 319         struct asd_sas_port *port = ev->port;
 320
 321         clear_bit(DISCE_DESTRUCT, &port->disc.pending);
 322
 323         list_for_each_entry_safe(dev, n, &port->destroy_list, disco_list_node) {
 324                 list_del_init(&dev->disco_list_node);
 325
 326                 sas_remove_children(&dev->rphy->dev);
 327                 sas_rphy_delete(dev->rphy);
 328                 sas_unregister_common_dev(port, dev);
 329         }
 330 }
 331
 332 void sas_unregister_dev(struct asd_sas_port *port, struct domain_device *dev)
 333 {
 334         if (!test_bit(SAS_DEV_DESTROY, &dev->state) &&
 335             !list_empty(&dev->disco_list_node)) {
 336                 /* this rphy never saw sas_rphy_add */
 337                 list_del_init(&dev->disco_list_node);
 338                 sas_rphy_free(dev->rphy);
 339                 sas_unregister_common_dev(port, dev);
 340                 return;
 341         }
 342
 343         if (!test_and_set_bit(SAS_DEV_DESTROY, &dev->state)) {
 344                 sas_rphy_unlink(dev->rphy);
 345                 list_move_tail(&dev->disco_list_node, &port->destroy_list);
 346                 sas_discover_event(dev->port, DISCE_DESTRUCT);
 347         }
 348 }
 349
 350 void sas_unregister_domain_devices(struct asd_sas_port *port, int gone)
 351 {
 352         struct domain_device *dev, *n;
 353
 354         list_for_each_entry_safe_reverse(dev, n, &port->dev_list, dev_list_node) {
 355                 if (gone)
 356                         set_bit(SAS_DEV_GONE, &dev->state);
 357                 sas_unregister_dev(port, dev);
 358         }
 359
 360         list_for_each_entry_safe(dev, n, &port->disco_list, disco_list_node)
 361                 sas_unregister_dev(port, dev);
 362
 363         port->port->rphy = NULL;
 364
 365 }
 366
 367 void sas_device_set_phy(struct domain_device *dev, struct sas_port *port)
 368 {
 369         struct sas_ha_struct *ha;
 370         struct sas_phy *new_phy;
 371
 372         if (!dev)
 373                 return;
 374
 375         ha = dev->port->ha;
 376         new_phy = sas_port_get_phy(port);
 377
 378         /* pin and record last seen phy */
 379         spin_lock_irq(&ha->phy_port_lock);
 380         if (new_phy) {
 381                 sas_port_put_phy(dev->phy);
 382                 dev->phy = new_phy;
 383         }
 384         spin_unlock_irq(&ha->phy_port_lock);
 385 }
 386
 387 /* ---------- Discovery and Revalidation ---------- */
 388
 389 /**
 390  * sas_discover_domain -- discover the domain
 391  * @port: port to the domain of interest
 392  *
 393  * NOTE: this process _must_ quit (return) as soon as any connection
 394  * errors are encountered.  Connection recovery is done elsewhere.
 395  * Discover process only interrogates devices in order to discover the
 396  * domain.
 397  */
 398 static void sas_discover_domain(struct work_struct *work)
 399 {
 400         struct domain_device *dev;
 401         int error = 0;
 402         struct sas_discovery_event *ev = to_sas_discovery_event(work);
 403         struct asd_sas_port *port = ev->port;
 404
 405         clear_bit(DISCE_DISCOVER_DOMAIN, &port->disc.pending);
 406
 407         if (port->port_dev)
 408                 return;
 409
 410         error = sas_get_port_device(port);
 411         if (error)
 412                 return;
 413         dev = port->port_dev;
 414
 415         SAS_DPRINTK("DOING DISCOVERY on port %d, pid:%d\n", port->id,
 416                     task_pid_nr(current));
 417
 418         switch (dev->dev_type) {
 419         case SAS_END_DEV:
 420                 error = sas_discover_end_dev(dev);
 421                 break;
 422         case EDGE_DEV:
 423         case FANOUT_DEV:
 424                 error = sas_discover_root_expander(dev);
 425                 break;
 426         case SATA_DEV:
 427         case SATA_PM:
 428 #ifdef CONFIG_SCSI_SAS_ATA
 429                 error = sas_discover_sata(dev);
 430                 break;
 431 #else
 432                 SAS_DPRINTK("ATA device seen but CONFIG_SCSI_SAS_ATA=N so cannot attach\n");
 433                 /* Fall through */
 434 #endif
 435         default:
 436                 error = -ENXIO;
 437                 SAS_DPRINTK("unhandled device %d\n", dev->dev_type);
 438                 break;
 439         }
 440
 441         if (error) {
 442                 sas_rphy_free(dev->rphy);
 443                 list_del_init(&dev->disco_list_node);
 444                 spin_lock_irq(&port->dev_list_lock);
 445                 list_del_init(&dev->dev_list_node);
 446                 spin_unlock_irq(&port->dev_list_lock);
 447
 448                 sas_put_device(dev);
 449                 port->port_dev = NULL;
 450         }
 451
 452         SAS_DPRINTK("DONE DISCOVERY on port %d, pid:%d, result:%d\n", port->id,
 453                     task_pid_nr(current), error);
 454 }
 455
 456 static void sas_revalidate_domain(struct work_struct *work)
 457 {
 458         int res = 0;
 459         struct sas_discovery_event *ev = to_sas_discovery_event(work);
 460         struct asd_sas_port *port = ev->port;
 461         struct sas_ha_struct *ha = port->ha;
 462
 463         /* prevent revalidation from finding sata links in recovery */
 464         mutex_lock(&ha->disco_mutex);
 465         if (test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state)) {
 466                 SAS_DPRINTK("REVALIDATION DEFERRED on port %d, pid:%d\n",
 467                             port->id, task_pid_nr(current));
 468                 goto out;
 469         }
 470
 471         clear_bit(DISCE_REVALIDATE_DOMAIN, &port->disc.pending);
 472
 473         SAS_DPRINTK("REVALIDATING DOMAIN on port %d, pid:%d\n", port->id,
 474                     task_pid_nr(current));
 475
 476         if (port->port_dev)
 477                 res = sas_ex_revalidate_domain(port->port_dev);
 478
 479         SAS_DPRINTK("done REVALIDATING DOMAIN on port %d, pid:%d, res 0x%x\n",
 480                     port->id, task_pid_nr(current), res);
 481  out:
 482         mutex_unlock(&ha->disco_mutex);
 483 }
 484
 485 /* ---------- Events ---------- */
 486
 487 static void sas_chain_work(struct sas_ha_struct *ha, struct sas_work *sw)
 488 {
 489         /* chained work is not subject to SA_HA_DRAINING or
 490          * SAS_HA_REGISTERED, because it is either submitted in the
 491          * workqueue, or known to be submitted from a context that is
 492          * not racing against draining
 493          */
 494         scsi_queue_work(ha->core.shost, &sw->work);
 495 }
 496
 497 static void sas_chain_event(int event, unsigned long *pending,
 498                             struct sas_work *sw,
 499                             struct sas_ha_struct *ha)
 500 {
 501         if (!test_and_set_bit(event, pending)) {
 502                 unsigned long flags;
 503
 504                 spin_lock_irqsave(&ha->lock, flags);
 505                 sas_chain_work(ha, sw);
 506                 spin_unlock_irqrestore(&ha->lock, flags);
 507         }
 508 }
 509
 510 int sas_discover_event(struct asd_sas_port *port, enum discover_event ev)
 511 {
 512         struct sas_discovery *disc;
 513
 514         if (!port)
 515                 return 0;
 516         disc = &port->disc;
 517
 518         BUG_ON(ev >= DISC_NUM_EVENTS);
 519
 520         sas_chain_event(ev, &disc->pending, &disc->disc_work[ev].work, port->ha);
 521
 522         return 0;
 523 }
 524
 525 /**
 526  * sas_init_disc -- initialize the discovery struct in the port
 527  * @port: pointer to struct port
 528  *
 529  * Called when the ports are being initialized.
 530  */
 531 void sas_init_disc(struct sas_discovery *disc, struct asd_sas_port *port)
 532 {
 533         int i;
 534
 535         static const work_func_t sas_event_fns[DISC_NUM_EVENTS] = {
 536                 [DISCE_DISCOVER_DOMAIN] = sas_discover_domain,
 537                 [DISCE_REVALIDATE_DOMAIN] = sas_revalidate_domain,
 538                 [DISCE_PROBE] = sas_probe_devices,
 539                 [DISCE_DESTRUCT] = sas_destruct_devices,
 540         };
 541
 542         disc->pending = 0;
 543         for (i = 0; i < DISC_NUM_EVENTS; i++) {
 544                 INIT_SAS_WORK(&disc->disc_work[i].work, sas_event_fns[i]);
 545                 disc->disc_work[i].port = port;
 546         }
 547 }