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