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