drivers/scsi/libsas/sas_init.c

   1 /*
   2  * Serial Attached SCSI (SAS) Transport Layer initialization
   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., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  22  * USA
  23  *
  24  */
  25
  26 #include <linux/module.h>
  27 #include <linux/slab.h>
  28 #include <linux/init.h>
  29 #include <linux/device.h>
  30 #include <linux/spinlock.h>
  31 #include <scsi/sas_ata.h>
  32 #include <scsi/scsi_host.h>
  33 #include <scsi/scsi_device.h>
  34 #include <scsi/scsi_transport.h>
  35 #include <scsi/scsi_transport_sas.h>
  36
  37 #include "sas_internal.h"
  38
  39 #include "../scsi_sas_internal.h"
  40
  41 static struct kmem_cache *sas_task_cache;
  42 static struct kmem_cache *sas_event_cache;
  43
  44 struct sas_task *sas_alloc_task(gfp_t flags)
  45 {
  46         struct sas_task *task = kmem_cache_zalloc(sas_task_cache, flags);
  47
  48         if (task) {
  49                 spin_lock_init(&task->task_state_lock);
  50                 task->task_state_flags = SAS_TASK_STATE_PENDING;
  51         }
  52
  53         return task;
  54 }
  55 EXPORT_SYMBOL_GPL(sas_alloc_task);
  56
  57 struct sas_task *sas_alloc_slow_task(gfp_t flags)
  58 {
  59         struct sas_task *task = sas_alloc_task(flags);
  60         struct sas_task_slow *slow = kmalloc(sizeof(*slow), flags);
  61
  62         if (!task || !slow) {
  63                 if (task)
  64                         kmem_cache_free(sas_task_cache, task);
  65                 kfree(slow);
  66                 return NULL;
  67         }
  68
  69         task->slow_task = slow;
  70         slow->task = task;
  71         timer_setup(&slow->timer, NULL, 0);
  72         init_completion(&slow->completion);
  73
  74         return task;
  75 }
  76 EXPORT_SYMBOL_GPL(sas_alloc_slow_task);
  77
  78 void sas_free_task(struct sas_task *task)
  79 {
  80         if (task) {
  81                 kfree(task->slow_task);
  82                 kmem_cache_free(sas_task_cache, task);
  83         }
  84 }
  85 EXPORT_SYMBOL_GPL(sas_free_task);
  86
  87 /*------------ SAS addr hash -----------*/
  88 void sas_hash_addr(u8 *hashed, const u8 *sas_addr)
  89 {
  90         const u32 poly = 0x00DB2777;
  91         u32     r = 0;
  92         int     i;
  93
  94         for (i = 0; i < 8; i++) {
  95                 int b;
  96                 for (b = 7; b >= 0; b--) {
  97                         r <<= 1;
  98                         if ((1 << b) & sas_addr[i]) {
  99                                 if (!(r & 0x01000000))
 100                                         r ^= poly;
 101                         } else if (r & 0x01000000)
 102                                 r ^= poly;
 103                 }
 104         }
 105
 106         hashed[0] = (r >> 16) & 0xFF;
 107         hashed[1] = (r >> 8) & 0xFF ;
 108         hashed[2] = r & 0xFF;
 109 }
 110
 111 int sas_register_ha(struct sas_ha_struct *sas_ha)
 112 {
 113         char name[64];
 114         int error = 0;
 115
 116         mutex_init(&sas_ha->disco_mutex);
 117         spin_lock_init(&sas_ha->phy_port_lock);
 118         sas_hash_addr(sas_ha->hashed_sas_addr, sas_ha->sas_addr);
 119
 120         set_bit(SAS_HA_REGISTERED, &sas_ha->state);
 121         spin_lock_init(&sas_ha->lock);
 122         mutex_init(&sas_ha->drain_mutex);
 123         init_waitqueue_head(&sas_ha->eh_wait_q);
 124         INIT_LIST_HEAD(&sas_ha->defer_q);
 125         INIT_LIST_HEAD(&sas_ha->eh_dev_q);
 126
 127         sas_ha->event_thres = SAS_PHY_SHUTDOWN_THRES;
 128
 129         error = sas_register_phys(sas_ha);
 130         if (error) {
 131                 printk(KERN_NOTICE "couldn't register sas phys:%d\n", error);
 132                 return error;
 133         }
 134
 135         error = sas_register_ports(sas_ha);
 136         if (error) {
 137                 printk(KERN_NOTICE "couldn't register sas ports:%d\n", error);
 138                 goto Undo_phys;
 139         }
 140
 141         error = sas_init_events(sas_ha);
 142         if (error) {
 143                 printk(KERN_NOTICE "couldn't start event thread:%d\n", error);
 144                 goto Undo_ports;
 145         }
 146
 147         error = -ENOMEM;
 148         snprintf(name, sizeof(name), "%s_event_q", dev_name(sas_ha->dev));
 149         sas_ha->event_q = create_singlethread_workqueue(name);
 150         if (!sas_ha->event_q)
 151                 goto Undo_ports;
 152
 153         snprintf(name, sizeof(name), "%s_disco_q", dev_name(sas_ha->dev));
 154         sas_ha->disco_q = create_singlethread_workqueue(name);
 155         if (!sas_ha->disco_q)
 156                 goto Undo_event_q;
 157
 158         INIT_LIST_HEAD(&sas_ha->eh_done_q);
 159         INIT_LIST_HEAD(&sas_ha->eh_ata_q);
 160
 161         return 0;
 162
 163 Undo_event_q:
 164         destroy_workqueue(sas_ha->event_q);
 165 Undo_ports:
 166         sas_unregister_ports(sas_ha);
 167 Undo_phys:
 168
 169         return error;
 170 }
 171
 172 static void sas_disable_events(struct sas_ha_struct *sas_ha)
 173 {
 174         /* Set the state to unregistered to avoid further unchained
 175          * events to be queued, and flush any in-progress drainers
 176          */
 177         mutex_lock(&sas_ha->drain_mutex);
 178         spin_lock_irq(&sas_ha->lock);
 179         clear_bit(SAS_HA_REGISTERED, &sas_ha->state);
 180         spin_unlock_irq(&sas_ha->lock);
 181         __sas_drain_work(sas_ha);
 182         mutex_unlock(&sas_ha->drain_mutex);
 183 }
 184
 185 int sas_unregister_ha(struct sas_ha_struct *sas_ha)
 186 {
 187         sas_disable_events(sas_ha);
 188         sas_unregister_ports(sas_ha);
 189
 190         /* flush unregistration work */
 191         mutex_lock(&sas_ha->drain_mutex);
 192         __sas_drain_work(sas_ha);
 193         mutex_unlock(&sas_ha->drain_mutex);
 194
 195         destroy_workqueue(sas_ha->disco_q);
 196         destroy_workqueue(sas_ha->event_q);
 197
 198         return 0;
 199 }
 200
 201 static int sas_get_linkerrors(struct sas_phy *phy)
 202 {
 203         if (scsi_is_sas_phy_local(phy)) {
 204                 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
 205                 struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
 206                 struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
 207                 struct sas_internal *i =
 208                         to_sas_internal(sas_ha->core.shost->transportt);
 209
 210                 return i->dft->lldd_control_phy(asd_phy, PHY_FUNC_GET_EVENTS, NULL);
 211         }
 212
 213         return sas_smp_get_phy_events(phy);
 214 }
 215
 216 int sas_try_ata_reset(struct asd_sas_phy *asd_phy)
 217 {
 218         struct domain_device *dev = NULL;
 219
 220         /* try to route user requested link resets through libata */
 221         if (asd_phy->port)
 222                 dev = asd_phy->port->port_dev;
 223
 224         /* validate that dev has been probed */
 225         if (dev)
 226                 dev = sas_find_dev_by_rphy(dev->rphy);
 227
 228         if (dev && dev_is_sata(dev)) {
 229                 sas_ata_schedule_reset(dev);
 230                 sas_ata_wait_eh(dev);
 231                 return 0;
 232         }
 233
 234         return -ENODEV;
 235 }
 236
 237 /*
 238  * transport_sas_phy_reset - reset a phy and permit libata to manage the link
 239  *
 240  * phy reset request via sysfs in host workqueue context so we know we
 241  * can block on eh and safely traverse the domain_device topology
 242  */
 243 static int transport_sas_phy_reset(struct sas_phy *phy, int hard_reset)
 244 {
 245         enum phy_func reset_type;
 246
 247         if (hard_reset)
 248                 reset_type = PHY_FUNC_HARD_RESET;
 249         else
 250                 reset_type = PHY_FUNC_LINK_RESET;
 251
 252         if (scsi_is_sas_phy_local(phy)) {
 253                 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
 254                 struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
 255                 struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
 256                 struct sas_internal *i =
 257                         to_sas_internal(sas_ha->core.shost->transportt);
 258
 259                 if (!hard_reset && sas_try_ata_reset(asd_phy) == 0)
 260                         return 0;
 261                 return i->dft->lldd_control_phy(asd_phy, reset_type, NULL);
 262         } else {
 263                 struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
 264                 struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
 265                 struct domain_device *ata_dev = sas_ex_to_ata(ddev, phy->number);
 266
 267                 if (ata_dev && !hard_reset) {
 268                         sas_ata_schedule_reset(ata_dev);
 269                         sas_ata_wait_eh(ata_dev);
 270                         return 0;
 271                 } else
 272                         return sas_smp_phy_control(ddev, phy->number, reset_type, NULL);
 273         }
 274 }
 275
 276 static int sas_phy_enable(struct sas_phy *phy, int enable)
 277 {
 278         int ret;
 279         enum phy_func cmd;
 280
 281         if (enable)
 282                 cmd = PHY_FUNC_LINK_RESET;
 283         else
 284                 cmd = PHY_FUNC_DISABLE;
 285
 286         if (scsi_is_sas_phy_local(phy)) {
 287                 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
 288                 struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
 289                 struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
 290                 struct sas_internal *i =
 291                         to_sas_internal(sas_ha->core.shost->transportt);
 292
 293                 if (enable)
 294                         ret = transport_sas_phy_reset(phy, 0);
 295                 else
 296                         ret = i->dft->lldd_control_phy(asd_phy, cmd, NULL);
 297         } else {
 298                 struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
 299                 struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
 300
 301                 if (enable)
 302                         ret = transport_sas_phy_reset(phy, 0);
 303                 else
 304                         ret = sas_smp_phy_control(ddev, phy->number, cmd, NULL);
 305         }
 306         return ret;
 307 }
 308
 309 int sas_phy_reset(struct sas_phy *phy, int hard_reset)
 310 {
 311         int ret;
 312         enum phy_func reset_type;
 313
 314         if (!phy->enabled)
 315                 return -ENODEV;
 316
 317         if (hard_reset)
 318                 reset_type = PHY_FUNC_HARD_RESET;
 319         else
 320                 reset_type = PHY_FUNC_LINK_RESET;
 321
 322         if (scsi_is_sas_phy_local(phy)) {
 323                 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
 324                 struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
 325                 struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
 326                 struct sas_internal *i =
 327                         to_sas_internal(sas_ha->core.shost->transportt);
 328
 329                 ret = i->dft->lldd_control_phy(asd_phy, reset_type, NULL);
 330         } else {
 331                 struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
 332                 struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
 333                 ret = sas_smp_phy_control(ddev, phy->number, reset_type, NULL);
 334         }
 335         return ret;
 336 }
 337
 338 int sas_set_phy_speed(struct sas_phy *phy,
 339                       struct sas_phy_linkrates *rates)
 340 {
 341         int ret;
 342
 343         if ((rates->minimum_linkrate &&
 344              rates->minimum_linkrate > phy->maximum_linkrate) ||
 345             (rates->maximum_linkrate &&
 346              rates->maximum_linkrate < phy->minimum_linkrate))
 347                 return -EINVAL;
 348
 349         if (rates->minimum_linkrate &&
 350             rates->minimum_linkrate < phy->minimum_linkrate_hw)
 351                 rates->minimum_linkrate = phy->minimum_linkrate_hw;
 352
 353         if (rates->maximum_linkrate &&
 354             rates->maximum_linkrate > phy->maximum_linkrate_hw)
 355                 rates->maximum_linkrate = phy->maximum_linkrate_hw;
 356
 357         if (scsi_is_sas_phy_local(phy)) {
 358                 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
 359                 struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
 360                 struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
 361                 struct sas_internal *i =
 362                         to_sas_internal(sas_ha->core.shost->transportt);
 363
 364                 ret = i->dft->lldd_control_phy(asd_phy, PHY_FUNC_SET_LINK_RATE,
 365                                                rates);
 366         } else {
 367                 struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
 368                 struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
 369                 ret = sas_smp_phy_control(ddev, phy->number,
 370                                           PHY_FUNC_LINK_RESET, rates);
 371
 372         }
 373
 374         return ret;
 375 }
 376
 377 void sas_prep_resume_ha(struct sas_ha_struct *ha)
 378 {
 379         int i;
 380
 381         set_bit(SAS_HA_REGISTERED, &ha->state);
 382
 383         /* clear out any stale link events/data from the suspension path */
 384         for (i = 0; i < ha->num_phys; i++) {
 385                 struct asd_sas_phy *phy = ha->sas_phy[i];
 386
 387                 memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
 388                 phy->frame_rcvd_size = 0;
 389         }
 390 }
 391 EXPORT_SYMBOL(sas_prep_resume_ha);
 392
 393 static int phys_suspended(struct sas_ha_struct *ha)
 394 {
 395         int i, rc = 0;
 396
 397         for (i = 0; i < ha->num_phys; i++) {
 398                 struct asd_sas_phy *phy = ha->sas_phy[i];
 399
 400                 if (phy->suspended)
 401                         rc++;
 402         }
 403
 404         return rc;
 405 }
 406
 407 void sas_resume_ha(struct sas_ha_struct *ha)
 408 {
 409         const unsigned long tmo = msecs_to_jiffies(25000);
 410         int i;
 411
 412         /* deform ports on phys that did not resume
 413          * at this point we may be racing the phy coming back (as posted
 414          * by the lldd).  So we post the event and once we are in the
 415          * libsas context check that the phy remains suspended before
 416          * tearing it down.
 417          */
 418         i = phys_suspended(ha);
 419         if (i)
 420                 dev_info(ha->dev, "waiting up to 25 seconds for %d phy%s to resume\n",
 421                          i, i > 1 ? "s" : "");
 422         wait_event_timeout(ha->eh_wait_q, phys_suspended(ha) == 0, tmo);
 423         for (i = 0; i < ha->num_phys; i++) {
 424                 struct asd_sas_phy *phy = ha->sas_phy[i];
 425
 426                 if (phy->suspended) {
 427                         dev_warn(&phy->phy->dev, "resume timeout\n");
 428                         sas_notify_phy_event(phy, PHYE_RESUME_TIMEOUT);
 429                 }
 430         }
 431
 432         /* all phys are back up or timed out, turn on i/o so we can
 433          * flush out disks that did not return
 434          */
 435         scsi_unblock_requests(ha->core.shost);
 436         sas_drain_work(ha);
 437 }
 438 EXPORT_SYMBOL(sas_resume_ha);
 439
 440 void sas_suspend_ha(struct sas_ha_struct *ha)
 441 {
 442         int i;
 443
 444         sas_disable_events(ha);
 445         scsi_block_requests(ha->core.shost);
 446         for (i = 0; i < ha->num_phys; i++) {
 447                 struct asd_sas_port *port = ha->sas_port[i];
 448
 449                 sas_discover_event(port, DISCE_SUSPEND);
 450         }
 451
 452         /* flush suspend events while unregistered */
 453         mutex_lock(&ha->drain_mutex);
 454         __sas_drain_work(ha);
 455         mutex_unlock(&ha->drain_mutex);
 456 }
 457 EXPORT_SYMBOL(sas_suspend_ha);
 458
 459 static void sas_phy_release(struct sas_phy *phy)
 460 {
 461         kfree(phy->hostdata);
 462         phy->hostdata = NULL;
 463 }
 464
 465 static void phy_reset_work(struct work_struct *work)
 466 {
 467         struct sas_phy_data *d = container_of(work, typeof(*d), reset_work.work);
 468
 469         d->reset_result = transport_sas_phy_reset(d->phy, d->hard_reset);
 470 }
 471
 472 static void phy_enable_work(struct work_struct *work)
 473 {
 474         struct sas_phy_data *d = container_of(work, typeof(*d), enable_work.work);
 475
 476         d->enable_result = sas_phy_enable(d->phy, d->enable);
 477 }
 478
 479 static int sas_phy_setup(struct sas_phy *phy)
 480 {
 481         struct sas_phy_data *d = kzalloc(sizeof(*d), GFP_KERNEL);
 482
 483         if (!d)
 484                 return -ENOMEM;
 485
 486         mutex_init(&d->event_lock);
 487         INIT_SAS_WORK(&d->reset_work, phy_reset_work);
 488         INIT_SAS_WORK(&d->enable_work, phy_enable_work);
 489         d->phy = phy;
 490         phy->hostdata = d;
 491
 492         return 0;
 493 }
 494
 495 static int queue_phy_reset(struct sas_phy *phy, int hard_reset)
 496 {
 497         struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
 498         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
 499         struct sas_phy_data *d = phy->hostdata;
 500         int rc;
 501
 502         if (!d)
 503                 return -ENOMEM;
 504
 505         /* libsas workqueue coordinates ata-eh reset with discovery */
 506         mutex_lock(&d->event_lock);
 507         d->reset_result = 0;
 508         d->hard_reset = hard_reset;
 509
 510         spin_lock_irq(&ha->lock);
 511         sas_queue_work(ha, &d->reset_work);
 512         spin_unlock_irq(&ha->lock);
 513
 514         rc = sas_drain_work(ha);
 515         if (rc == 0)
 516                 rc = d->reset_result;
 517         mutex_unlock(&d->event_lock);
 518
 519         return rc;
 520 }
 521
 522 static int queue_phy_enable(struct sas_phy *phy, int enable)
 523 {
 524         struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
 525         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
 526         struct sas_phy_data *d = phy->hostdata;
 527         int rc;
 528
 529         if (!d)
 530                 return -ENOMEM;
 531
 532         /* libsas workqueue coordinates ata-eh reset with discovery */
 533         mutex_lock(&d->event_lock);
 534         d->enable_result = 0;
 535         d->enable = enable;
 536
 537         spin_lock_irq(&ha->lock);
 538         sas_queue_work(ha, &d->enable_work);
 539         spin_unlock_irq(&ha->lock);
 540
 541         rc = sas_drain_work(ha);
 542         if (rc == 0)
 543                 rc = d->enable_result;
 544         mutex_unlock(&d->event_lock);
 545
 546         return rc;
 547 }
 548
 549 static struct sas_function_template sft = {
 550         .phy_enable = queue_phy_enable,
 551         .phy_reset = queue_phy_reset,
 552         .phy_setup = sas_phy_setup,
 553         .phy_release = sas_phy_release,
 554         .set_phy_speed = sas_set_phy_speed,
 555         .get_linkerrors = sas_get_linkerrors,
 556         .smp_handler = sas_smp_handler,
 557 };
 558
 559 static inline ssize_t phy_event_threshold_show(struct device *dev,
 560                         struct device_attribute *attr, char *buf)
 561 {
 562         struct Scsi_Host *shost = class_to_shost(dev);
 563         struct sas_ha_struct *sha = SHOST_TO_SAS_HA(shost);
 564
 565         return scnprintf(buf, PAGE_SIZE, "%u\n", sha->event_thres);
 566 }
 567
 568 static inline ssize_t phy_event_threshold_store(struct device *dev,
 569                         struct device_attribute *attr,
 570                         const char *buf, size_t count)
 571 {
 572         struct Scsi_Host *shost = class_to_shost(dev);
 573         struct sas_ha_struct *sha = SHOST_TO_SAS_HA(shost);
 574
 575         sha->event_thres = simple_strtol(buf, NULL, 10);
 576
 577         /* threshold cannot be set too small */
 578         if (sha->event_thres < 32)
 579                 sha->event_thres = 32;
 580
 581         return count;
 582 }
 583
 584 DEVICE_ATTR(phy_event_threshold,
 585         S_IRUGO|S_IWUSR,
 586         phy_event_threshold_show,
 587         phy_event_threshold_store);
 588 EXPORT_SYMBOL_GPL(dev_attr_phy_event_threshold);
 589
 590 struct scsi_transport_template *
 591 sas_domain_attach_transport(struct sas_domain_function_template *dft)
 592 {
 593         struct scsi_transport_template *stt = sas_attach_transport(&sft);
 594         struct sas_internal *i;
 595
 596         if (!stt)
 597                 return stt;
 598
 599         i = to_sas_internal(stt);
 600         i->dft = dft;
 601         stt->create_work_queue = 1;
 602         stt->eh_strategy_handler = sas_scsi_recover_host;
 603
 604         return stt;
 605 }
 606 EXPORT_SYMBOL_GPL(sas_domain_attach_transport);
 607
 608
 609 struct asd_sas_event *sas_alloc_event(struct asd_sas_phy *phy)
 610 {
 611         struct asd_sas_event *event;
 612         gfp_t flags = in_interrupt() ? GFP_ATOMIC : GFP_KERNEL;
 613         struct sas_ha_struct *sas_ha = phy->ha;
 614         struct sas_internal *i =
 615                 to_sas_internal(sas_ha->core.shost->transportt);
 616
 617         event = kmem_cache_zalloc(sas_event_cache, flags);
 618         if (!event)
 619                 return NULL;
 620
 621         atomic_inc(&phy->event_nr);
 622
 623         if (atomic_read(&phy->event_nr) > phy->ha->event_thres) {
 624                 if (i->dft->lldd_control_phy) {
 625                         if (cmpxchg(&phy->in_shutdown, 0, 1) == 0) {
 626                                 sas_printk("The phy%02d bursting events, shut it down.\n",
 627                                         phy->id);
 628                                 sas_notify_phy_event(phy, PHYE_SHUTDOWN);
 629                         }
 630                 } else {
 631                         /* Do not support PHY control, stop allocating events */
 632                         WARN_ONCE(1, "PHY control not supported.\n");
 633                         kmem_cache_free(sas_event_cache, event);
 634                         atomic_dec(&phy->event_nr);
 635                         event = NULL;
 636                 }
 637         }
 638
 639         return event;
 640 }
 641
 642 void sas_free_event(struct asd_sas_event *event)
 643 {
 644         struct asd_sas_phy *phy = event->phy;
 645
 646         kmem_cache_free(sas_event_cache, event);
 647         atomic_dec(&phy->event_nr);
 648 }
 649
 650 /* ---------- SAS Class register/unregister ---------- */
 651
 652 static int __init sas_class_init(void)
 653 {
 654         sas_task_cache = KMEM_CACHE(sas_task, SLAB_HWCACHE_ALIGN);
 655         if (!sas_task_cache)
 656                 goto out;
 657
 658         sas_event_cache = KMEM_CACHE(asd_sas_event, SLAB_HWCACHE_ALIGN);
 659         if (!sas_event_cache)
 660                 goto free_task_kmem;
 661
 662         return 0;
 663 free_task_kmem:
 664         kmem_cache_destroy(sas_task_cache);
 665 out:
 666         return -ENOMEM;
 667 }
 668
 669 static void __exit sas_class_exit(void)
 670 {
 671         kmem_cache_destroy(sas_task_cache);
 672         kmem_cache_destroy(sas_event_cache);
 673 }
 674
 675 MODULE_AUTHOR("Luben Tuikov <luben_tuikov@adaptec.com>");
 676 MODULE_DESCRIPTION("SAS Transport Layer");
 677 MODULE_LICENSE("GPL v2");
 678
 679 module_init(sas_class_init);
 680 module_exit(sas_class_exit);
 681
 682 EXPORT_SYMBOL_GPL(sas_register_ha);
 683 EXPORT_SYMBOL_GPL(sas_unregister_ha);