drivers/s390/scsi/zfcp_scsi.c

   1 /*
   2  * This file is part of the zfcp device driver for
   3  * FCP adapters for IBM System z9 and zSeries.
   4  *
   5  * (C) Copyright IBM Corp. 2002, 2006
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2, or (at your option)
  10  * any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20  */
  21
  22 #define ZFCP_LOG_AREA                   ZFCP_LOG_AREA_SCSI
  23
  24 #include "zfcp_ext.h"
  25 #include <asm/atomic.h>
  26
  27 static void zfcp_scsi_slave_destroy(struct scsi_device *sdp);
  28 static int zfcp_scsi_slave_alloc(struct scsi_device *sdp);
  29 static int zfcp_scsi_slave_configure(struct scsi_device *sdp);
  30 static int zfcp_scsi_queuecommand(struct scsi_cmnd *,
  31                                   void (*done) (struct scsi_cmnd *));
  32 static int zfcp_scsi_eh_abort_handler(struct scsi_cmnd *);
  33 static int zfcp_scsi_eh_device_reset_handler(struct scsi_cmnd *);
  34 static int zfcp_scsi_eh_host_reset_handler(struct scsi_cmnd *);
  35 static int zfcp_task_management_function(struct zfcp_unit *, u8,
  36                                          struct scsi_cmnd *);
  37
  38 static struct zfcp_unit *zfcp_unit_lookup(struct zfcp_adapter *, int,
  39                                           unsigned int, unsigned int);
  40
  41 static struct device_attribute *zfcp_sysfs_sdev_attrs[];
  42
  43 struct zfcp_data zfcp_data = {
  44         .scsi_host_template = {
  45                 .name                   = ZFCP_NAME,
  46                 .module                 = THIS_MODULE,
  47                 .proc_name              = "zfcp",
  48                 .slave_alloc            = zfcp_scsi_slave_alloc,
  49                 .slave_configure        = zfcp_scsi_slave_configure,
  50                 .slave_destroy          = zfcp_scsi_slave_destroy,
  51                 .queuecommand           = zfcp_scsi_queuecommand,
  52                 .eh_abort_handler       = zfcp_scsi_eh_abort_handler,
  53                 .eh_device_reset_handler = zfcp_scsi_eh_device_reset_handler,
  54                 .eh_host_reset_handler  = zfcp_scsi_eh_host_reset_handler,
  55                 .can_queue              = 4096,
  56                 .this_id                = -1,
  57                 .sg_tablesize           = ZFCP_MAX_SBALES_PER_REQ,
  58                 .cmd_per_lun            = 1,
  59                 .use_clustering         = 1,
  60                 .sdev_attrs             = zfcp_sysfs_sdev_attrs,
  61                 .max_sectors            = ZFCP_MAX_SECTORS,
  62         },
  63         .driver_version = ZFCP_VERSION,
  64 };
  65
  66 /* Find start of Response Information in FCP response unit*/
  67 char *
  68 zfcp_get_fcp_rsp_info_ptr(struct fcp_rsp_iu *fcp_rsp_iu)
  69 {
  70         char *fcp_rsp_info_ptr;
  71
  72         fcp_rsp_info_ptr =
  73             (unsigned char *) fcp_rsp_iu + (sizeof (struct fcp_rsp_iu));
  74
  75         return fcp_rsp_info_ptr;
  76 }
  77
  78 /* Find start of Sense Information in FCP response unit*/
  79 char *
  80 zfcp_get_fcp_sns_info_ptr(struct fcp_rsp_iu *fcp_rsp_iu)
  81 {
  82         char *fcp_sns_info_ptr;
  83
  84         fcp_sns_info_ptr =
  85             (unsigned char *) fcp_rsp_iu + (sizeof (struct fcp_rsp_iu));
  86         if (fcp_rsp_iu->validity.bits.fcp_rsp_len_valid)
  87                 fcp_sns_info_ptr = (char *) fcp_sns_info_ptr +
  88                     fcp_rsp_iu->fcp_rsp_len;
  89
  90         return fcp_sns_info_ptr;
  91 }
  92
  93 static fcp_dl_t *
  94 zfcp_get_fcp_dl_ptr(struct fcp_cmnd_iu * fcp_cmd)
  95 {
  96         int additional_length = fcp_cmd->add_fcp_cdb_length << 2;
  97         fcp_dl_t *fcp_dl_addr;
  98
  99         fcp_dl_addr = (fcp_dl_t *)
 100                 ((unsigned char *) fcp_cmd +
 101                  sizeof (struct fcp_cmnd_iu) + additional_length);
 102         /*
 103          * fcp_dl_addr = start address of fcp_cmnd structure +
 104          * size of fixed part + size of dynamically sized add_dcp_cdb field
 105          * SEE FCP-2 documentation
 106          */
 107         return fcp_dl_addr;
 108 }
 109
 110 fcp_dl_t
 111 zfcp_get_fcp_dl(struct fcp_cmnd_iu * fcp_cmd)
 112 {
 113         return *zfcp_get_fcp_dl_ptr(fcp_cmd);
 114 }
 115
 116 void
 117 zfcp_set_fcp_dl(struct fcp_cmnd_iu *fcp_cmd, fcp_dl_t fcp_dl)
 118 {
 119         *zfcp_get_fcp_dl_ptr(fcp_cmd) = fcp_dl;
 120 }
 121
 122 /*
 123  * note: it's a bit-or operation not an assignment
 124  * regarding the specified byte
 125  */
 126 static inline void
 127 set_byte(int *result, char status, char pos)
 128 {
 129         *result |= status << (pos * 8);
 130 }
 131
 132 void
 133 set_host_byte(int *result, char status)
 134 {
 135         set_byte(result, status, 2);
 136 }
 137
 138 void
 139 set_driver_byte(int *result, char status)
 140 {
 141         set_byte(result, status, 3);
 142 }
 143
 144 static int
 145 zfcp_scsi_slave_alloc(struct scsi_device *sdp)
 146 {
 147         struct zfcp_adapter *adapter;
 148         struct zfcp_unit *unit;
 149         unsigned long flags;
 150         int retval = -ENXIO;
 151
 152         adapter = (struct zfcp_adapter *) sdp->host->hostdata[0];
 153         if (!adapter)
 154                 goto out;
 155
 156         read_lock_irqsave(&zfcp_data.config_lock, flags);
 157         unit = zfcp_unit_lookup(adapter, sdp->channel, sdp->id, sdp->lun);
 158         if (unit && atomic_test_mask(ZFCP_STATUS_UNIT_REGISTERED,
 159                                      &unit->status)) {
 160                 sdp->hostdata = unit;
 161                 unit->device = sdp;
 162                 zfcp_unit_get(unit);
 163                 retval = 0;
 164         }
 165         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
 166  out:
 167         return retval;
 168 }
 169
 170 /**
 171  * zfcp_scsi_slave_destroy - called when scsi device is removed
 172  *
 173  * Remove reference to associated scsi device for an zfcp_unit.
 174  * Mark zfcp_unit as failed. The scsi device might be deleted via sysfs
 175  * or a scan for this device might have failed.
 176  */
 177 static void zfcp_scsi_slave_destroy(struct scsi_device *sdpnt)
 178 {
 179         struct zfcp_unit *unit = (struct zfcp_unit *) sdpnt->hostdata;
 180
 181         if (unit) {
 182                 zfcp_erp_wait(unit->port->adapter);
 183                 atomic_clear_mask(ZFCP_STATUS_UNIT_REGISTERED, &unit->status);
 184                 sdpnt->hostdata = NULL;
 185                 unit->device = NULL;
 186                 zfcp_erp_unit_failed(unit);
 187                 zfcp_unit_put(unit);
 188         } else
 189                 ZFCP_LOG_NORMAL("bug: no unit associated with SCSI device at "
 190                                 "address %p\n", sdpnt);
 191 }
 192
 193 /*
 194  * called from scsi midlayer to allow finetuning of a device.
 195  */
 196 static int
 197 zfcp_scsi_slave_configure(struct scsi_device *sdp)
 198 {
 199         if (sdp->tagged_supported)
 200                 scsi_adjust_queue_depth(sdp, MSG_SIMPLE_TAG, ZFCP_CMND_PER_LUN);
 201         else
 202                 scsi_adjust_queue_depth(sdp, 0, 1);
 203         return 0;
 204 }
 205
 206 /**
 207  * zfcp_scsi_command_fail - set result in scsi_cmnd and call scsi_done function
 208  * @scpnt: pointer to struct scsi_cmnd where result is set
 209  * @result: result to be set in scpnt (e.g. DID_ERROR)
 210  */
 211 static void
 212 zfcp_scsi_command_fail(struct scsi_cmnd *scpnt, int result)
 213 {
 214         set_host_byte(&scpnt->result, result);
 215         if ((scpnt->device != NULL) && (scpnt->device->host != NULL))
 216                 zfcp_scsi_dbf_event_result("fail", 4,
 217                         (struct zfcp_adapter*) scpnt->device->host->hostdata[0],
 218                         scpnt, NULL);
 219         /* return directly */
 220         scpnt->scsi_done(scpnt);
 221 }
 222
 223 /**
 224  * zfcp_scsi_command_async - worker for zfcp_scsi_queuecommand and
 225  *      zfcp_scsi_command_sync
 226  * @adapter: adapter where scsi command is issued
 227  * @unit: unit to which scsi command is sent
 228  * @scpnt: scsi command to be sent
 229  * @timer: timer to be started if request is successfully initiated
 230  *
 231  * Note: In scsi_done function must be set in scpnt.
 232  */
 233 int
 234 zfcp_scsi_command_async(struct zfcp_adapter *adapter, struct zfcp_unit *unit,
 235                         struct scsi_cmnd *scpnt, int use_timer)
 236 {
 237         int tmp;
 238         int retval;
 239
 240         retval = 0;
 241
 242         BUG_ON((adapter == NULL) || (adapter != unit->port->adapter));
 243         BUG_ON(scpnt->scsi_done == NULL);
 244
 245         if (unlikely(NULL == unit)) {
 246                 zfcp_scsi_command_fail(scpnt, DID_NO_CONNECT);
 247                 goto out;
 248         }
 249
 250         if (unlikely(
 251               atomic_test_mask(ZFCP_STATUS_COMMON_ERP_FAILED, &unit->status) ||
 252              !atomic_test_mask(ZFCP_STATUS_COMMON_RUNNING, &unit->status))) {
 253                 ZFCP_LOG_DEBUG("stopping SCSI I/O on unit 0x%016Lx on port "
 254                                "0x%016Lx on adapter %s\n",
 255                                unit->fcp_lun, unit->port->wwpn,
 256                                zfcp_get_busid_by_adapter(adapter));
 257                 zfcp_scsi_command_fail(scpnt, DID_ERROR);
 258                 goto out;
 259         }
 260
 261         tmp = zfcp_fsf_send_fcp_command_task(adapter, unit, scpnt, use_timer,
 262                                              ZFCP_REQ_AUTO_CLEANUP);
 263         if (unlikely(tmp == -EBUSY)) {
 264                 ZFCP_LOG_DEBUG("adapter %s not ready or unit 0x%016Lx "
 265                                "on port 0x%016Lx in recovery\n",
 266                                zfcp_get_busid_by_unit(unit),
 267                                unit->fcp_lun, unit->port->wwpn);
 268                 zfcp_scsi_command_fail(scpnt, DID_NO_CONNECT);
 269                 goto out;
 270         }
 271
 272         if (unlikely(tmp < 0)) {
 273                 ZFCP_LOG_DEBUG("error: initiation of Send FCP Cmnd failed\n");
 274                 retval = SCSI_MLQUEUE_HOST_BUSY;
 275         }
 276
 277 out:
 278         return retval;
 279 }
 280
 281 static void
 282 zfcp_scsi_command_sync_handler(struct scsi_cmnd *scpnt)
 283 {
 284         struct completion *wait = (struct completion *) scpnt->SCp.ptr;
 285         complete(wait);
 286 }
 287
 288
 289 /**
 290  * zfcp_scsi_command_sync - send a SCSI command and wait for completion
 291  * @unit: unit where command is sent to
 292  * @scpnt: scsi command to be sent
 293  * @use_timer: indicates whether timer should be setup or not
 294  * Return: 0
 295  *
 296  * Errors are indicated in scpnt->result
 297  */
 298 int
 299 zfcp_scsi_command_sync(struct zfcp_unit *unit, struct scsi_cmnd *scpnt,
 300                        int use_timer)
 301 {
 302         int ret;
 303         DECLARE_COMPLETION_ONSTACK(wait);
 304
 305         scpnt->SCp.ptr = (void *) &wait;  /* silent re-use */
 306         scpnt->scsi_done = zfcp_scsi_command_sync_handler;
 307         ret = zfcp_scsi_command_async(unit->port->adapter, unit, scpnt,
 308                                       use_timer);
 309         if (ret == 0)
 310                 wait_for_completion(&wait);
 311
 312         scpnt->SCp.ptr = NULL;
 313
 314         return 0;
 315 }
 316
 317 /*
 318  * function:    zfcp_scsi_queuecommand
 319  *
 320  * purpose:     enqueues a SCSI command to the specified target device
 321  *
 322  * returns:     0 - success, SCSI command enqueued
 323  *              !0 - failure
 324  */
 325 static int
 326 zfcp_scsi_queuecommand(struct scsi_cmnd *scpnt,
 327                        void (*done) (struct scsi_cmnd *))
 328 {
 329         struct zfcp_unit *unit;
 330         struct zfcp_adapter *adapter;
 331
 332         /* reset the status for this request */
 333         scpnt->result = 0;
 334         scpnt->host_scribble = NULL;
 335         scpnt->scsi_done = done;
 336
 337         /*
 338          * figure out adapter and target device
 339          * (stored there by zfcp_scsi_slave_alloc)
 340          */
 341         adapter = (struct zfcp_adapter *) scpnt->device->host->hostdata[0];
 342         unit = (struct zfcp_unit *) scpnt->device->hostdata;
 343
 344         return zfcp_scsi_command_async(adapter, unit, scpnt, 0);
 345 }
 346
 347 static struct zfcp_unit *
 348 zfcp_unit_lookup(struct zfcp_adapter *adapter, int channel, unsigned int id,
 349                  unsigned int lun)
 350 {
 351         struct zfcp_port *port;
 352         struct zfcp_unit *unit, *retval = NULL;
 353
 354         list_for_each_entry(port, &adapter->port_list_head, list) {
 355                 if (!port->rport || (id != port->rport->scsi_target_id))
 356                         continue;
 357                 list_for_each_entry(unit, &port->unit_list_head, list)
 358                         if (lun == unit->scsi_lun) {
 359                                 retval = unit;
 360                                 goto out;
 361                         }
 362         }
 363  out:
 364         return retval;
 365 }
 366
 367 /**
 368  * zfcp_scsi_eh_abort_handler - abort the specified SCSI command
 369  * @scpnt: pointer to scsi_cmnd to be aborted
 370  * Return: SUCCESS - command has been aborted and cleaned up in internal
 371  *          bookkeeping, SCSI stack won't be called for aborted command
 372  *         FAILED - otherwise
 373  *
 374  * We do not need to care for a SCSI command which completes normally
 375  * but late during this abort routine runs.  We are allowed to return
 376  * late commands to the SCSI stack.  It tracks the state of commands and
 377  * will handle late commands.  (Usually, the normal completion of late
 378  * commands is ignored with respect to the running abort operation.)
 379  */
 380 static int zfcp_scsi_eh_abort_handler(struct scsi_cmnd *scpnt)
 381 {
 382         struct Scsi_Host *scsi_host;
 383         struct zfcp_adapter *adapter;
 384         struct zfcp_unit *unit;
 385         struct zfcp_fsf_req *fsf_req;
 386         unsigned long flags;
 387         unsigned long old_req_id;
 388         int retval = SUCCESS;
 389
 390         scsi_host = scpnt->device->host;
 391         adapter = (struct zfcp_adapter *) scsi_host->hostdata[0];
 392         unit = (struct zfcp_unit *) scpnt->device->hostdata;
 393
 394         ZFCP_LOG_INFO("aborting scsi_cmnd=%p on adapter %s\n",
 395                       scpnt, zfcp_get_busid_by_adapter(adapter));
 396
 397         /* avoid race condition between late normal completion and abort */
 398         write_lock_irqsave(&adapter->abort_lock, flags);
 399
 400         /* Check whether corresponding fsf_req is still pending */
 401         spin_lock(&adapter->req_list_lock);
 402         fsf_req = zfcp_reqlist_find(adapter,
 403                                     (unsigned long) scpnt->host_scribble);
 404         spin_unlock(&adapter->req_list_lock);
 405         if (!fsf_req) {
 406                 write_unlock_irqrestore(&adapter->abort_lock, flags);
 407                 zfcp_scsi_dbf_event_abort("lte1", adapter, scpnt, NULL, 0);
 408                 retval = SUCCESS;
 409                 goto out;
 410         }
 411         fsf_req->data = 0;
 412         fsf_req->status |= ZFCP_STATUS_FSFREQ_ABORTING;
 413         old_req_id = fsf_req->req_id;
 414
 415         /* don't access old fsf_req after releasing the abort_lock */
 416         write_unlock_irqrestore(&adapter->abort_lock, flags);
 417
 418         fsf_req = zfcp_fsf_abort_fcp_command(old_req_id, adapter, unit, 0);
 419         if (!fsf_req) {
 420                 ZFCP_LOG_INFO("error: initiation of Abort FCP Cmnd failed\n");
 421                 zfcp_scsi_dbf_event_abort("nres", adapter, scpnt, NULL,
 422                                           old_req_id);
 423                 retval = FAILED;
 424                 goto out;
 425         }
 426
 427         __wait_event(fsf_req->completion_wq,
 428                      fsf_req->status & ZFCP_STATUS_FSFREQ_COMPLETED);
 429
 430         if (fsf_req->status & ZFCP_STATUS_FSFREQ_ABORTSUCCEEDED) {
 431                 zfcp_scsi_dbf_event_abort("okay", adapter, scpnt, fsf_req, 0);
 432                 retval = SUCCESS;
 433         } else if (fsf_req->status & ZFCP_STATUS_FSFREQ_ABORTNOTNEEDED) {
 434                 zfcp_scsi_dbf_event_abort("lte2", adapter, scpnt, fsf_req, 0);
 435                 retval = SUCCESS;
 436         } else {
 437                 zfcp_scsi_dbf_event_abort("fail", adapter, scpnt, fsf_req, 0);
 438                 retval = FAILED;
 439         }
 440         zfcp_fsf_req_free(fsf_req);
 441  out:
 442         return retval;
 443 }
 444
 445 static int
 446 zfcp_scsi_eh_device_reset_handler(struct scsi_cmnd *scpnt)
 447 {
 448         int retval;
 449         struct zfcp_unit *unit = (struct zfcp_unit *) scpnt->device->hostdata;
 450
 451         if (!unit) {
 452                 ZFCP_LOG_NORMAL("bug: Tried reset for nonexistent unit\n");
 453                 retval = SUCCESS;
 454                 goto out;
 455         }
 456         ZFCP_LOG_NORMAL("resetting unit 0x%016Lx on port 0x%016Lx, adapter %s\n",
 457                         unit->fcp_lun, unit->port->wwpn,
 458                         zfcp_get_busid_by_adapter(unit->port->adapter));
 459
 460         /*
 461          * If we do not know whether the unit supports 'logical unit reset'
 462          * then try 'logical unit reset' and proceed with 'target reset'
 463          * if 'logical unit reset' fails.
 464          * If the unit is known not to support 'logical unit reset' then
 465          * skip 'logical unit reset' and try 'target reset' immediately.
 466          */
 467         if (!atomic_test_mask(ZFCP_STATUS_UNIT_NOTSUPPUNITRESET,
 468                               &unit->status)) {
 469                 retval = zfcp_task_management_function(unit,
 470                                                        FCP_LOGICAL_UNIT_RESET,
 471                                                        scpnt);
 472                 if (retval) {
 473                         ZFCP_LOG_DEBUG("unit reset failed (unit=%p)\n", unit);
 474                         if (retval == -ENOTSUPP)
 475                                 atomic_set_mask
 476                                     (ZFCP_STATUS_UNIT_NOTSUPPUNITRESET,
 477                                      &unit->status);
 478                         /* fall through and try 'target reset' next */
 479                 } else {
 480                         ZFCP_LOG_DEBUG("unit reset succeeded (unit=%p)\n",
 481                                        unit);
 482                         /* avoid 'target reset' */
 483                         retval = SUCCESS;
 484                         goto out;
 485                 }
 486         }
 487         retval = zfcp_task_management_function(unit, FCP_TARGET_RESET, scpnt);
 488         if (retval) {
 489                 ZFCP_LOG_DEBUG("target reset failed (unit=%p)\n", unit);
 490                 retval = FAILED;
 491         } else {
 492                 ZFCP_LOG_DEBUG("target reset succeeded (unit=%p)\n", unit);
 493                 retval = SUCCESS;
 494         }
 495  out:
 496         return retval;
 497 }
 498
 499 static int
 500 zfcp_task_management_function(struct zfcp_unit *unit, u8 tm_flags,
 501                               struct scsi_cmnd *scpnt)
 502 {
 503         struct zfcp_adapter *adapter = unit->port->adapter;
 504         struct zfcp_fsf_req *fsf_req;
 505         int retval = 0;
 506
 507         /* issue task management function */
 508         fsf_req = zfcp_fsf_send_fcp_command_task_management
 509                 (adapter, unit, tm_flags, 0);
 510         if (!fsf_req) {
 511                 ZFCP_LOG_INFO("error: creation of task management request "
 512                               "failed for unit 0x%016Lx on port 0x%016Lx on  "
 513                               "adapter %s\n", unit->fcp_lun, unit->port->wwpn,
 514                               zfcp_get_busid_by_adapter(adapter));
 515                 zfcp_scsi_dbf_event_devreset("nres", tm_flags, unit, scpnt);
 516                 retval = -ENOMEM;
 517                 goto out;
 518         }
 519
 520         __wait_event(fsf_req->completion_wq,
 521                      fsf_req->status & ZFCP_STATUS_FSFREQ_COMPLETED);
 522
 523         /*
 524          * check completion status of task management function
 525          */
 526         if (fsf_req->status & ZFCP_STATUS_FSFREQ_TMFUNCFAILED) {
 527                 zfcp_scsi_dbf_event_devreset("fail", tm_flags, unit, scpnt);
 528                 retval = -EIO;
 529         } else if (fsf_req->status & ZFCP_STATUS_FSFREQ_TMFUNCNOTSUPP) {
 530                 zfcp_scsi_dbf_event_devreset("nsup", tm_flags, unit, scpnt);
 531                 retval = -ENOTSUPP;
 532         } else
 533                 zfcp_scsi_dbf_event_devreset("okay", tm_flags, unit, scpnt);
 534
 535         zfcp_fsf_req_free(fsf_req);
 536  out:
 537         return retval;
 538 }
 539
 540 /**
 541  * zfcp_scsi_eh_host_reset_handler - handler for host reset
 542  */
 543 static int zfcp_scsi_eh_host_reset_handler(struct scsi_cmnd *scpnt)
 544 {
 545         struct zfcp_unit *unit;
 546         struct zfcp_adapter *adapter;
 547
 548         unit = (struct zfcp_unit*) scpnt->device->hostdata;
 549         adapter = unit->port->adapter;
 550
 551         ZFCP_LOG_NORMAL("host reset because of problems with "
 552                 "unit 0x%016Lx on port 0x%016Lx, adapter %s\n",
 553                 unit->fcp_lun, unit->port->wwpn,
 554                 zfcp_get_busid_by_adapter(unit->port->adapter));
 555
 556         zfcp_erp_adapter_reopen(adapter, 0);
 557         zfcp_erp_wait(adapter);
 558
 559         return SUCCESS;
 560 }
 561
 562 int
 563 zfcp_adapter_scsi_register(struct zfcp_adapter *adapter)
 564 {
 565         int retval = 0;
 566         static unsigned int unique_id = 0;
 567
 568         if (adapter->scsi_host)
 569                 goto out;
 570
 571         /* register adapter as SCSI host with mid layer of SCSI stack */
 572         adapter->scsi_host = scsi_host_alloc(&zfcp_data.scsi_host_template,
 573                                              sizeof (struct zfcp_adapter *));
 574         if (!adapter->scsi_host) {
 575                 ZFCP_LOG_NORMAL("error: registration with SCSI stack failed "
 576                                 "for adapter %s ",
 577                                 zfcp_get_busid_by_adapter(adapter));
 578                 retval = -EIO;
 579                 goto out;
 580         }
 581         ZFCP_LOG_DEBUG("host registered, scsi_host=%p\n", adapter->scsi_host);
 582
 583         /* tell the SCSI stack some characteristics of this adapter */
 584         adapter->scsi_host->max_id = 1;
 585         adapter->scsi_host->max_lun = 1;
 586         adapter->scsi_host->max_channel = 0;
 587         adapter->scsi_host->unique_id = unique_id++;    /* FIXME */
 588         adapter->scsi_host->max_cmd_len = ZFCP_MAX_SCSI_CMND_LENGTH;
 589         adapter->scsi_host->transportt = zfcp_data.scsi_transport_template;
 590
 591         /*
 592          * save a pointer to our own adapter data structure within
 593          * hostdata field of SCSI host data structure
 594          */
 595         adapter->scsi_host->hostdata[0] = (unsigned long) adapter;
 596
 597         if (scsi_add_host(adapter->scsi_host, &adapter->ccw_device->dev)) {
 598                 scsi_host_put(adapter->scsi_host);
 599                 retval = -EIO;
 600                 goto out;
 601         }
 602         atomic_set_mask(ZFCP_STATUS_ADAPTER_REGISTERED, &adapter->status);
 603  out:
 604         return retval;
 605 }
 606
 607 void
 608 zfcp_adapter_scsi_unregister(struct zfcp_adapter *adapter)
 609 {
 610         struct Scsi_Host *shost;
 611         struct zfcp_port *port;
 612
 613         shost = adapter->scsi_host;
 614         if (!shost)
 615                 return;
 616         read_lock_irq(&zfcp_data.config_lock);
 617         list_for_each_entry(port, &adapter->port_list_head, list)
 618                 if (port->rport)
 619                         port->rport = NULL;
 620         read_unlock_irq(&zfcp_data.config_lock);
 621         fc_remove_host(shost);
 622         scsi_remove_host(shost);
 623         scsi_host_put(shost);
 624         adapter->scsi_host = NULL;
 625         atomic_clear_mask(ZFCP_STATUS_ADAPTER_REGISTERED, &adapter->status);
 626
 627         return;
 628 }
 629
 630 /*
 631  * Support functions for FC transport class
 632  */
 633 static struct fc_host_statistics*
 634 zfcp_init_fc_host_stats(struct zfcp_adapter *adapter)
 635 {
 636         struct fc_host_statistics *fc_stats;
 637
 638         if (!adapter->fc_stats) {
 639                 fc_stats = kmalloc(sizeof(*fc_stats), GFP_KERNEL);
 640                 if (!fc_stats)
 641                         return NULL;
 642                 adapter->fc_stats = fc_stats; /* freed in adater_dequeue */
 643         }
 644         memset(adapter->fc_stats, 0, sizeof(*adapter->fc_stats));
 645         return adapter->fc_stats;
 646 }
 647
 648 static void
 649 zfcp_adjust_fc_host_stats(struct fc_host_statistics *fc_stats,
 650                           struct fsf_qtcb_bottom_port *data,
 651                           struct fsf_qtcb_bottom_port *old)
 652 {
 653         fc_stats->seconds_since_last_reset = data->seconds_since_last_reset -
 654                 old->seconds_since_last_reset;
 655         fc_stats->tx_frames = data->tx_frames - old->tx_frames;
 656         fc_stats->tx_words = data->tx_words - old->tx_words;
 657         fc_stats->rx_frames = data->rx_frames - old->rx_frames;
 658         fc_stats->rx_words = data->rx_words - old->rx_words;
 659         fc_stats->lip_count = data->lip - old->lip;
 660         fc_stats->nos_count = data->nos - old->nos;
 661         fc_stats->error_frames = data->error_frames - old->error_frames;
 662         fc_stats->dumped_frames = data->dumped_frames - old->dumped_frames;
 663         fc_stats->link_failure_count = data->link_failure - old->link_failure;
 664         fc_stats->loss_of_sync_count = data->loss_of_sync - old->loss_of_sync;
 665         fc_stats->loss_of_signal_count = data->loss_of_signal -
 666                 old->loss_of_signal;
 667         fc_stats->prim_seq_protocol_err_count = data->psp_error_counts -
 668                 old->psp_error_counts;
 669         fc_stats->invalid_tx_word_count = data->invalid_tx_words -
 670                 old->invalid_tx_words;
 671         fc_stats->invalid_crc_count = data->invalid_crcs - old->invalid_crcs;
 672         fc_stats->fcp_input_requests = data->input_requests -
 673                 old->input_requests;
 674         fc_stats->fcp_output_requests = data->output_requests -
 675                 old->output_requests;
 676         fc_stats->fcp_control_requests = data->control_requests -
 677                 old->control_requests;
 678         fc_stats->fcp_input_megabytes = data->input_mb - old->input_mb;
 679         fc_stats->fcp_output_megabytes = data->output_mb - old->output_mb;
 680 }
 681
 682 static void
 683 zfcp_set_fc_host_stats(struct fc_host_statistics *fc_stats,
 684                        struct fsf_qtcb_bottom_port *data)
 685 {
 686         fc_stats->seconds_since_last_reset = data->seconds_since_last_reset;
 687         fc_stats->tx_frames = data->tx_frames;
 688         fc_stats->tx_words = data->tx_words;
 689         fc_stats->rx_frames = data->rx_frames;
 690         fc_stats->rx_words = data->rx_words;
 691         fc_stats->lip_count = data->lip;
 692         fc_stats->nos_count = data->nos;
 693         fc_stats->error_frames = data->error_frames;
 694         fc_stats->dumped_frames = data->dumped_frames;
 695         fc_stats->link_failure_count = data->link_failure;
 696         fc_stats->loss_of_sync_count = data->loss_of_sync;
 697         fc_stats->loss_of_signal_count = data->loss_of_signal;
 698         fc_stats->prim_seq_protocol_err_count = data->psp_error_counts;
 699         fc_stats->invalid_tx_word_count = data->invalid_tx_words;
 700         fc_stats->invalid_crc_count = data->invalid_crcs;
 701         fc_stats->fcp_input_requests = data->input_requests;
 702         fc_stats->fcp_output_requests = data->output_requests;
 703         fc_stats->fcp_control_requests = data->control_requests;
 704         fc_stats->fcp_input_megabytes = data->input_mb;
 705         fc_stats->fcp_output_megabytes = data->output_mb;
 706 }
 707
 708 /**
 709  * zfcp_get_fc_host_stats - provide fc_host_statistics for scsi_transport_fc
 710  *
 711  * assumption: scsi_transport_fc synchronizes calls of
 712  *             get_fc_host_stats and reset_fc_host_stats
 713  *             (XXX to be checked otherwise introduce locking)
 714  */
 715 static struct fc_host_statistics *
 716 zfcp_get_fc_host_stats(struct Scsi_Host *shost)
 717 {
 718         struct zfcp_adapter *adapter;
 719         struct fc_host_statistics *fc_stats;
 720         struct fsf_qtcb_bottom_port *data;
 721         int ret;
 722
 723         adapter = (struct zfcp_adapter *)shost->hostdata[0];
 724         fc_stats = zfcp_init_fc_host_stats(adapter);
 725         if (!fc_stats)
 726                 return NULL;
 727
 728         data = kzalloc(sizeof(*data), GFP_KERNEL);
 729         if (!data)
 730                 return NULL;
 731
 732         ret = zfcp_fsf_exchange_port_data_sync(adapter, data);
 733         if (ret) {
 734                 kfree(data);
 735                 return NULL; /* XXX return zeroed fc_stats? */
 736         }
 737
 738         if (adapter->stats_reset &&
 739             ((jiffies/HZ - adapter->stats_reset) <
 740              data->seconds_since_last_reset)) {
 741                 zfcp_adjust_fc_host_stats(fc_stats, data,
 742                                           adapter->stats_reset_data);
 743         } else
 744                 zfcp_set_fc_host_stats(fc_stats, data);
 745
 746         kfree(data);
 747         return fc_stats;
 748 }
 749
 750 static void
 751 zfcp_reset_fc_host_stats(struct Scsi_Host *shost)
 752 {
 753         struct zfcp_adapter *adapter;
 754         struct fsf_qtcb_bottom_port *data, *old_data;
 755         int ret;
 756
 757         adapter = (struct zfcp_adapter *)shost->hostdata[0];
 758         data = kzalloc(sizeof(*data), GFP_KERNEL);
 759         if (!data)
 760                 return;
 761
 762         ret = zfcp_fsf_exchange_port_data_sync(adapter, data);
 763         if (ret) {
 764                 kfree(data);
 765         } else {
 766                 adapter->stats_reset = jiffies/HZ;
 767                 old_data = adapter->stats_reset_data;
 768                 adapter->stats_reset_data = data; /* finally freed in
 769                                                      adater_dequeue */
 770                 kfree(old_data);
 771         }
 772 }
 773
 774 static void zfcp_set_rport_dev_loss_tmo(struct fc_rport *rport, u32 timeout)
 775 {
 776         rport->dev_loss_tmo = timeout;
 777 }
 778
 779 struct fc_function_template zfcp_transport_functions = {
 780         .show_starget_port_id = 1,
 781         .show_starget_port_name = 1,
 782         .show_starget_node_name = 1,
 783         .show_rport_supported_classes = 1,
 784         .show_rport_maxframe_size = 1,
 785         .show_rport_dev_loss_tmo = 1,
 786         .show_host_node_name = 1,
 787         .show_host_port_name = 1,
 788         .show_host_permanent_port_name = 1,
 789         .show_host_supported_classes = 1,
 790         .show_host_supported_speeds = 1,
 791         .show_host_maxframe_size = 1,
 792         .show_host_serial_number = 1,
 793         .get_fc_host_stats = zfcp_get_fc_host_stats,
 794         .reset_fc_host_stats = zfcp_reset_fc_host_stats,
 795         .set_rport_dev_loss_tmo = zfcp_set_rport_dev_loss_tmo,
 796         /* no functions registered for following dynamic attributes but
 797            directly set by LLDD */
 798         .show_host_port_type = 1,
 799         .show_host_speed = 1,
 800         .show_host_port_id = 1,
 801         .disable_target_scan = 1,
 802 };
 803
 804 /**
 805  * ZFCP_DEFINE_SCSI_ATTR
 806  * @_name:   name of show attribute
 807  * @_format: format string
 808  * @_value:  value to print
 809  *
 810  * Generates attribute for a unit.
 811  */
 812 #define ZFCP_DEFINE_SCSI_ATTR(_name, _format, _value)                    \
 813 static ssize_t zfcp_sysfs_scsi_##_name##_show(struct device *dev, struct device_attribute *attr,        \
 814                                               char *buf)                 \
 815 {                                                                        \
 816         struct scsi_device *sdev;                                        \
 817         struct zfcp_unit *unit;                                          \
 818                                                                          \
 819         sdev = to_scsi_device(dev);                                      \
 820         unit = sdev->hostdata;                                           \
 821         return sprintf(buf, _format, _value);                            \
 822 }                                                                        \
 823                                                                          \
 824 static DEVICE_ATTR(_name, S_IRUGO, zfcp_sysfs_scsi_##_name##_show, NULL);
 825
 826 ZFCP_DEFINE_SCSI_ATTR(hba_id, "%s\n", zfcp_get_busid_by_unit(unit));
 827 ZFCP_DEFINE_SCSI_ATTR(wwpn, "0x%016llx\n", unit->port->wwpn);
 828 ZFCP_DEFINE_SCSI_ATTR(fcp_lun, "0x%016llx\n", unit->fcp_lun);
 829
 830 static struct device_attribute *zfcp_sysfs_sdev_attrs[] = {
 831         &dev_attr_fcp_lun,
 832         &dev_attr_wwpn,
 833         &dev_attr_hba_id,
 834         NULL
 835 };
 836
 837 #undef ZFCP_LOG_AREA