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