git.oblomov.eu Git - linux-2.6/blob - 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_bus_reset_handler   = zfcp_scsi_eh_host_reset_handler,
  55                 .eh_host_reset_handler  = zfcp_scsi_eh_host_reset_handler,
  56                 .can_queue              = 4096,
  57                 .this_id                = -1,
  58                 .sg_tablesize           = ZFCP_MAX_SBALES_PER_REQ,
  59                 .cmd_per_lun            = 1,
  60                 .use_clustering         = 1,
  61                 .sdev_attrs             = zfcp_sysfs_sdev_attrs,
  62                 .max_sectors            = ZFCP_MAX_SECTORS,
  63         },
  64         .driver_version = ZFCP_VERSION,
  65 };
  66
  67 /* Find start of Response Information in FCP response unit*/
  68 char *
  69 zfcp_get_fcp_rsp_info_ptr(struct fcp_rsp_iu *fcp_rsp_iu)
  70 {
  71         char *fcp_rsp_info_ptr;
  72
  73         fcp_rsp_info_ptr =
  74             (unsigned char *) fcp_rsp_iu + (sizeof (struct fcp_rsp_iu));
  75
  76         return fcp_rsp_info_ptr;
  77 }
  78
  79 /* Find start of Sense Information in FCP response unit*/
  80 char *
  81 zfcp_get_fcp_sns_info_ptr(struct fcp_rsp_iu *fcp_rsp_iu)
  82 {
  83         char *fcp_sns_info_ptr;
  84
  85         fcp_sns_info_ptr =
  86             (unsigned char *) fcp_rsp_iu + (sizeof (struct fcp_rsp_iu));
  87         if (fcp_rsp_iu->validity.bits.fcp_rsp_len_valid)
  88                 fcp_sns_info_ptr = (char *) fcp_sns_info_ptr +
  89                     fcp_rsp_iu->fcp_rsp_len;
  90
  91         return fcp_sns_info_ptr;
  92 }
  93
  94 static fcp_dl_t *
  95 zfcp_get_fcp_dl_ptr(struct fcp_cmnd_iu * fcp_cmd)
  96 {
  97         int additional_length = fcp_cmd->add_fcp_cdb_length << 2;
  98         fcp_dl_t *fcp_dl_addr;
  99
 100         fcp_dl_addr = (fcp_dl_t *)
 101                 ((unsigned char *) fcp_cmd +
 102                  sizeof (struct fcp_cmnd_iu) + additional_length);
 103         /*
 104          * fcp_dl_addr = start address of fcp_cmnd structure +
 105          * size of fixed part + size of dynamically sized add_dcp_cdb field
 106          * SEE FCP-2 documentation
 107          */
 108         return fcp_dl_addr;
 109 }
 110
 111 fcp_dl_t
 112 zfcp_get_fcp_dl(struct fcp_cmnd_iu * fcp_cmd)
 113 {
 114         return *zfcp_get_fcp_dl_ptr(fcp_cmd);
 115 }
 116
 117 void
 118 zfcp_set_fcp_dl(struct fcp_cmnd_iu *fcp_cmd, fcp_dl_t fcp_dl)
 119 {
 120         *zfcp_get_fcp_dl_ptr(fcp_cmd) = fcp_dl;
 121 }
 122
 123 /*
 124  * note: it's a bit-or operation not an assignment
 125  * regarding the specified byte
 126  */
 127 static inline void
 128 set_byte(int *result, char status, char pos)
 129 {
 130         *result |= status << (pos * 8);
 131 }
 132
 133 void
 134 set_host_byte(int *result, char status)
 135 {
 136         set_byte(result, status, 2);
 137 }
 138
 139 void
 140 set_driver_byte(int *result, char status)
 141 {
 142         set_byte(result, status, 3);
 143 }
 144
 145 static int
 146 zfcp_scsi_slave_alloc(struct scsi_device *sdp)
 147 {
 148         struct zfcp_adapter *adapter;
 149         struct zfcp_unit *unit;
 150         unsigned long flags;
 151         int retval = -ENXIO;
 152
 153         adapter = (struct zfcp_adapter *) sdp->host->hostdata[0];
 154         if (!adapter)
 155                 goto out;
 156
 157         read_lock_irqsave(&zfcp_data.config_lock, flags);
 158         unit = zfcp_unit_lookup(adapter, sdp->channel, sdp->id, sdp->lun);
 159         if (unit && atomic_test_mask(ZFCP_STATUS_UNIT_REGISTERED,
 160                                      &unit->status)) {
 161                 sdp->hostdata = unit;
 162                 unit->device = sdp;
 163                 zfcp_unit_get(unit);
 164                 retval = 0;
 165         }
 166         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
 167  out:
 168         return retval;
 169 }
 170
 171 /**
 172  * zfcp_scsi_slave_destroy - called when scsi device is removed
 173  *
 174  * Remove reference to associated scsi device for an zfcp_unit.
 175  * Mark zfcp_unit as failed. The scsi device might be deleted via sysfs
 176  * or a scan for this device might have failed.
 177  */
 178 static void zfcp_scsi_slave_destroy(struct scsi_device *sdpnt)
 179 {
 180         struct zfcp_unit *unit = (struct zfcp_unit *) sdpnt->hostdata;
 181
 182         if (unit) {
 183                 zfcp_erp_wait(unit->port->adapter);
 184                 wait_event(unit->scsi_scan_wq,
 185                            atomic_test_mask(ZFCP_STATUS_UNIT_SCSI_WORK_PENDING,
 186                                             &unit->status) == 0);
 187                 atomic_clear_mask(ZFCP_STATUS_UNIT_REGISTERED, &unit->status);
 188                 sdpnt->hostdata = NULL;
 189                 unit->device = NULL;
 190                 zfcp_erp_unit_failed(unit);
 191                 zfcp_unit_put(unit);
 192         } else
 193                 ZFCP_LOG_NORMAL("bug: no unit associated with SCSI device at "
 194                                 "address %p\n", sdpnt);
 195 }
 196
 197 /*
 198  * called from scsi midlayer to allow finetuning of a device.
 199  */
 200 static int
 201 zfcp_scsi_slave_configure(struct scsi_device *sdp)
 202 {
 203         if (sdp->tagged_supported)
 204                 scsi_adjust_queue_depth(sdp, MSG_SIMPLE_TAG, ZFCP_CMND_PER_LUN);
 205         else
 206                 scsi_adjust_queue_depth(sdp, 0, 1);
 207         return 0;
 208 }
 209
 210 /**
 211  * zfcp_scsi_command_fail - set result in scsi_cmnd and call scsi_done function
 212  * @scpnt: pointer to struct scsi_cmnd where result is set
 213  * @result: result to be set in scpnt (e.g. DID_ERROR)
 214  */
 215 static void
 216 zfcp_scsi_command_fail(struct scsi_cmnd *scpnt, int result)
 217 {
 218         set_host_byte(&scpnt->result, result);
 219         if ((scpnt->device != NULL) && (scpnt->device->host != NULL))
 220                 zfcp_scsi_dbf_event_result("fail", 4,
 221                         (struct zfcp_adapter*) scpnt->device->host->hostdata[0],
 222                         scpnt, NULL);
 223         /* return directly */
 224         scpnt->scsi_done(scpnt);
 225 }
 226
 227 /**
 228  * zfcp_scsi_command_async - worker for zfcp_scsi_queuecommand and
 229  *      zfcp_scsi_command_sync
 230  * @adapter: adapter where scsi command is issued
 231  * @unit: unit to which scsi command is sent
 232  * @scpnt: scsi command to be sent
 233  * @timer: timer to be started if request is successfully initiated
 234  *
 235  * Note: In scsi_done function must be set in scpnt.
 236  */
 237 int
 238 zfcp_scsi_command_async(struct zfcp_adapter *adapter, struct zfcp_unit *unit,
 239                         struct scsi_cmnd *scpnt, int use_timer)
 240 {
 241         int tmp;
 242         int retval;
 243
 244         retval = 0;
 245
 246         BUG_ON((adapter == NULL) || (adapter != unit->port->adapter));
 247         BUG_ON(scpnt->scsi_done == NULL);
 248
 249         if (unlikely(NULL == unit)) {
 250                 zfcp_scsi_command_fail(scpnt, DID_NO_CONNECT);
 251                 goto out;
 252         }
 253
 254         if (unlikely(
 255               atomic_test_mask(ZFCP_STATUS_COMMON_ERP_FAILED, &unit->status) ||
 256              !atomic_test_mask(ZFCP_STATUS_COMMON_RUNNING, &unit->status))) {
 257                 ZFCP_LOG_DEBUG("stopping SCSI I/O on unit 0x%016Lx on port "
 258                                "0x%016Lx on adapter %s\n",
 259                                unit->fcp_lun, unit->port->wwpn,
 260                                zfcp_get_busid_by_adapter(adapter));
 261                 zfcp_scsi_command_fail(scpnt, DID_ERROR);
 262                 goto out;
 263         }
 264
 265         if (unlikely(
 266              !atomic_test_mask(ZFCP_STATUS_COMMON_UNBLOCKED, &unit->status))) {
 267                 ZFCP_LOG_DEBUG("adapter %s not ready or unit 0x%016Lx "
 268                                "on port 0x%016Lx in recovery\n",
 269                                zfcp_get_busid_by_unit(unit),
 270                                unit->fcp_lun, unit->port->wwpn);
 271                 zfcp_scsi_command_fail(scpnt, DID_NO_CONNECT);
 272                 goto out;
 273         }
 274
 275         tmp = zfcp_fsf_send_fcp_command_task(adapter, unit, scpnt, use_timer,
 276                                              ZFCP_REQ_AUTO_CLEANUP);
 277
 278         if (unlikely(tmp < 0)) {
 279                 ZFCP_LOG_DEBUG("error: initiation of Send FCP Cmnd failed\n");
 280                 retval = SCSI_MLQUEUE_HOST_BUSY;
 281         }
 282
 283 out:
 284         return retval;
 285 }
 286
 287 static void
 288 zfcp_scsi_command_sync_handler(struct scsi_cmnd *scpnt)
 289 {
 290         struct completion *wait = (struct completion *) scpnt->SCp.ptr;
 291         complete(wait);
 292 }
 293
 294
 295 /**
 296  * zfcp_scsi_command_sync - send a SCSI command and wait for completion
 297  * @unit: unit where command is sent to
 298  * @scpnt: scsi command to be sent
 299  * @use_timer: indicates whether timer should be setup or not
 300  * Return: 0
 301  *
 302  * Errors are indicated in scpnt->result
 303  */
 304 int
 305 zfcp_scsi_command_sync(struct zfcp_unit *unit, struct scsi_cmnd *scpnt,
 306                        int use_timer)
 307 {
 308         int ret;
 309         DECLARE_COMPLETION_ONSTACK(wait);
 310
 311         scpnt->SCp.ptr = (void *) &wait;  /* silent re-use */
 312         scpnt->scsi_done = zfcp_scsi_command_sync_handler;
 313         ret = zfcp_scsi_command_async(unit->port->adapter, unit, scpnt,
 314                                       use_timer);
 315         if (ret == 0)
 316                 wait_for_completion(&wait);
 317
 318         scpnt->SCp.ptr = NULL;
 319
 320         return 0;
 321 }
 322
 323 /*
 324  * function:    zfcp_scsi_queuecommand
 325  *
 326  * purpose:     enqueues a SCSI command to the specified target device
 327  *
 328  * returns:     0 - success, SCSI command enqueued
 329  *              !0 - failure
 330  */
 331 static int
 332 zfcp_scsi_queuecommand(struct scsi_cmnd *scpnt,
 333                        void (*done) (struct scsi_cmnd *))
 334 {
 335         struct zfcp_unit *unit;
 336         struct zfcp_adapter *adapter;
 337
 338         /* reset the status for this request */
 339         scpnt->result = 0;
 340         scpnt->host_scribble = NULL;
 341         scpnt->scsi_done = done;
 342
 343         /*
 344          * figure out adapter and target device
 345          * (stored there by zfcp_scsi_slave_alloc)
 346          */
 347         adapter = (struct zfcp_adapter *) scpnt->device->host->hostdata[0];
 348         unit = (struct zfcp_unit *) scpnt->device->hostdata;
 349
 350         return zfcp_scsi_command_async(adapter, unit, scpnt, 0);
 351 }
 352
 353 static struct zfcp_unit *
 354 zfcp_unit_lookup(struct zfcp_adapter *adapter, int channel, unsigned int id,
 355                  unsigned int lun)
 356 {
 357         struct zfcp_port *port;
 358         struct zfcp_unit *unit, *retval = NULL;
 359
 360         list_for_each_entry(port, &adapter->port_list_head, list) {
 361                 if (!port->rport || (id != port->rport->scsi_target_id))
 362                         continue;
 363                 list_for_each_entry(unit, &port->unit_list_head, list)
 364                         if (lun == unit->scsi_lun) {
 365                                 retval = unit;
 366                                 goto out;
 367                         }
 368         }
 369  out:
 370         return retval;
 371 }
 372
 373 /**
 374  * zfcp_scsi_eh_abort_handler - abort the specified SCSI command
 375  * @scpnt: pointer to scsi_cmnd to be aborted
 376  * Return: SUCCESS - command has been aborted and cleaned up in internal
 377  *          bookkeeping, SCSI stack won't be called for aborted command
 378  *         FAILED - otherwise
 379  *
 380  * We do not need to care for a SCSI command which completes normally
 381  * but late during this abort routine runs.  We are allowed to return
 382  * late commands to the SCSI stack.  It tracks the state of commands and
 383  * will handle late commands.  (Usually, the normal completion of late
 384  * commands is ignored with respect to the running abort operation.)
 385  */
 386 static int zfcp_scsi_eh_abort_handler(struct scsi_cmnd *scpnt)
 387 {
 388         struct Scsi_Host *scsi_host;
 389         struct zfcp_adapter *adapter;
 390         struct zfcp_unit *unit;
 391         struct zfcp_fsf_req *fsf_req;
 392         unsigned long flags;
 393         unsigned long old_req_id;
 394         int retval = SUCCESS;
 395
 396         scsi_host = scpnt->device->host;
 397         adapter = (struct zfcp_adapter *) scsi_host->hostdata[0];
 398         unit = (struct zfcp_unit *) scpnt->device->hostdata;
 399
 400         ZFCP_LOG_INFO("aborting scsi_cmnd=%p on adapter %s\n",
 401                       scpnt, zfcp_get_busid_by_adapter(adapter));
 402
 403         /* avoid race condition between late normal completion and abort */
 404         write_lock_irqsave(&adapter->abort_lock, flags);
 405
 406         /* Check whether corresponding fsf_req is still pending */
 407         spin_lock(&adapter->req_list_lock);
 408         fsf_req = zfcp_reqlist_find(adapter,
 409                                     (unsigned long) scpnt->host_scribble);
 410         spin_unlock(&adapter->req_list_lock);
 411         if (!fsf_req) {
 412                 write_unlock_irqrestore(&adapter->abort_lock, flags);
 413                 zfcp_scsi_dbf_event_abort("lte1", adapter, scpnt, NULL, 0);
 414                 retval = SUCCESS;
 415                 goto out;
 416         }
 417         fsf_req->data = 0;
 418         fsf_req->status |= ZFCP_STATUS_FSFREQ_ABORTING;
 419         old_req_id = fsf_req->req_id;
 420
 421         /* don't access old fsf_req after releasing the abort_lock */
 422         write_unlock_irqrestore(&adapter->abort_lock, flags);
 423
 424         fsf_req = zfcp_fsf_abort_fcp_command(old_req_id, adapter, unit, 0);
 425         if (!fsf_req) {
 426                 ZFCP_LOG_INFO("error: initiation of Abort FCP Cmnd failed\n");
 427                 zfcp_scsi_dbf_event_abort("nres", adapter, scpnt, NULL,
 428                                           old_req_id);
 429                 retval = FAILED;
 430                 goto out;
 431         }
 432
 433         __wait_event(fsf_req->completion_wq,
 434                      fsf_req->status & ZFCP_STATUS_FSFREQ_COMPLETED);
 435
 436         if (fsf_req->status & ZFCP_STATUS_FSFREQ_ABORTSUCCEEDED) {
 437                 zfcp_scsi_dbf_event_abort("okay", adapter, scpnt, fsf_req, 0);
 438                 retval = SUCCESS;
 439         } else if (fsf_req->status & ZFCP_STATUS_FSFREQ_ABORTNOTNEEDED) {
 440                 zfcp_scsi_dbf_event_abort("lte2", adapter, scpnt, fsf_req, 0);
 441                 retval = SUCCESS;
 442         } else {
 443                 zfcp_scsi_dbf_event_abort("fail", adapter, scpnt, fsf_req, 0);
 444                 retval = FAILED;
 445         }
 446         zfcp_fsf_req_free(fsf_req);
 447  out:
 448         return retval;
 449 }
 450
 451 static int
 452 zfcp_scsi_eh_device_reset_handler(struct scsi_cmnd *scpnt)
 453 {
 454         int retval;
 455         struct zfcp_unit *unit = (struct zfcp_unit *) scpnt->device->hostdata;
 456
 457         if (!unit) {
 458                 ZFCP_LOG_NORMAL("bug: Tried reset for nonexistent unit\n");
 459                 retval = SUCCESS;
 460                 goto out;
 461         }
 462         ZFCP_LOG_NORMAL("resetting unit 0x%016Lx\n", unit->fcp_lun);
 463
 464         /*
 465          * If we do not know whether the unit supports 'logical unit reset'
 466          * then try 'logical unit reset' and proceed with 'target reset'
 467          * if 'logical unit reset' fails.
 468          * If the unit is known not to support 'logical unit reset' then
 469          * skip 'logical unit reset' and try 'target reset' immediately.
 470          */
 471         if (!atomic_test_mask(ZFCP_STATUS_UNIT_NOTSUPPUNITRESET,
 472                               &unit->status)) {
 473                 retval = zfcp_task_management_function(unit,
 474                                                        FCP_LOGICAL_UNIT_RESET,
 475                                                        scpnt);
 476                 if (retval) {
 477                         ZFCP_LOG_DEBUG("unit reset failed (unit=%p)\n", unit);
 478                         if (retval == -ENOTSUPP)
 479                                 atomic_set_mask
 480                                     (ZFCP_STATUS_UNIT_NOTSUPPUNITRESET,
 481                                      &unit->status);
 482                         /* fall through and try 'target reset' next */
 483                 } else {
 484                         ZFCP_LOG_DEBUG("unit reset succeeded (unit=%p)\n",
 485                                        unit);
 486                         /* avoid 'target reset' */
 487                         retval = SUCCESS;
 488                         goto out;
 489                 }
 490         }
 491         retval = zfcp_task_management_function(unit, FCP_TARGET_RESET, scpnt);
 492         if (retval) {
 493                 ZFCP_LOG_DEBUG("target reset failed (unit=%p)\n", unit);
 494                 retval = FAILED;
 495         } else {
 496                 ZFCP_LOG_DEBUG("target reset succeeded (unit=%p)\n", unit);
 497                 retval = SUCCESS;
 498         }
 499  out:
 500         return retval;
 501 }
 502
 503 static int
 504 zfcp_task_management_function(struct zfcp_unit *unit, u8 tm_flags,
 505                               struct scsi_cmnd *scpnt)
 506 {
 507         struct zfcp_adapter *adapter = unit->port->adapter;
 508         struct zfcp_fsf_req *fsf_req;
 509         int retval = 0;
 510
 511         /* issue task management function */
 512         fsf_req = zfcp_fsf_send_fcp_command_task_management
 513                 (adapter, unit, tm_flags, 0);
 514         if (!fsf_req) {
 515                 ZFCP_LOG_INFO("error: creation of task management request "
 516                               "failed for unit 0x%016Lx on port 0x%016Lx on  "
 517                               "adapter %s\n", unit->fcp_lun, unit->port->wwpn,
 518                               zfcp_get_busid_by_adapter(adapter));
 519                 zfcp_scsi_dbf_event_devreset("nres", tm_flags, unit, scpnt);
 520                 retval = -ENOMEM;
 521                 goto out;
 522         }
 523
 524         __wait_event(fsf_req->completion_wq,
 525                      fsf_req->status & ZFCP_STATUS_FSFREQ_COMPLETED);
 526
 527         /*
 528          * check completion status of task management function
 529          */
 530         if (fsf_req->status & ZFCP_STATUS_FSFREQ_TMFUNCFAILED) {
 531                 zfcp_scsi_dbf_event_devreset("fail", tm_flags, unit, scpnt);
 532                 retval = -EIO;
 533         } else if (fsf_req->status & ZFCP_STATUS_FSFREQ_TMFUNCNOTSUPP) {
 534                 zfcp_scsi_dbf_event_devreset("nsup", tm_flags, unit, scpnt);
 535                 retval = -ENOTSUPP;
 536         } else
 537                 zfcp_scsi_dbf_event_devreset("okay", tm_flags, unit, scpnt);
 538
 539         zfcp_fsf_req_free(fsf_req);
 540  out:
 541         return retval;
 542 }
 543
 544 /**
 545  * zfcp_scsi_eh_host_reset_handler - handler for host and bus reset
 546  */
 547 static int zfcp_scsi_eh_host_reset_handler(struct scsi_cmnd *scpnt)
 548 {
 549         struct zfcp_unit *unit;
 550         struct zfcp_adapter *adapter;
 551
 552         unit = (struct zfcp_unit*) scpnt->device->hostdata;
 553         adapter = unit->port->adapter;
 554
 555         ZFCP_LOG_NORMAL("host/bus reset because of problems with "
 556                         "unit 0x%016Lx\n", unit->fcp_lun);
 557
 558         zfcp_erp_adapter_reopen(adapter, 0);
 559         zfcp_erp_wait(adapter);
 560
 561         return SUCCESS;
 562 }
 563
 564 int
 565 zfcp_adapter_scsi_register(struct zfcp_adapter *adapter)
 566 {
 567         int retval = 0;
 568         static unsigned int unique_id = 0;
 569
 570         if (adapter->scsi_host)
 571                 goto out;
 572
 573         /* register adapter as SCSI host with mid layer of SCSI stack */
 574         adapter->scsi_host = scsi_host_alloc(&zfcp_data.scsi_host_template,
 575                                              sizeof (struct zfcp_adapter *));
 576         if (!adapter->scsi_host) {
 577                 ZFCP_LOG_NORMAL("error: registration with SCSI stack failed "
 578                                 "for adapter %s ",
 579                                 zfcp_get_busid_by_adapter(adapter));
 580                 retval = -EIO;
 581                 goto out;
 582         }
 583         ZFCP_LOG_DEBUG("host registered, scsi_host=%p\n", adapter->scsi_host);
 584
 585         /* tell the SCSI stack some characteristics of this adapter */
 586         adapter->scsi_host->max_id = 1;
 587         adapter->scsi_host->max_lun = 1;
 588         adapter->scsi_host->max_channel = 0;
 589         adapter->scsi_host->unique_id = unique_id++;    /* FIXME */
 590         adapter->scsi_host->max_cmd_len = ZFCP_MAX_SCSI_CMND_LENGTH;
 591         adapter->scsi_host->transportt = zfcp_data.scsi_transport_template;
 592
 593         /*
 594          * save a pointer to our own adapter data structure within
 595          * hostdata field of SCSI host data structure
 596          */
 597         adapter->scsi_host->hostdata[0] = (unsigned long) adapter;
 598
 599         if (scsi_add_host(adapter->scsi_host, &adapter->ccw_device->dev)) {
 600                 scsi_host_put(adapter->scsi_host);
 601                 retval = -EIO;
 602                 goto out;
 603         }
 604         atomic_set_mask(ZFCP_STATUS_ADAPTER_REGISTERED, &adapter->status);
 605  out:
 606         return retval;
 607 }
 608
 609 void
 610 zfcp_adapter_scsi_unregister(struct zfcp_adapter *adapter)
 611 {
 612         struct Scsi_Host *shost;
 613         struct zfcp_port *port;
 614
 615         shost = adapter->scsi_host;
 616         if (!shost)
 617                 return;
 618         read_lock_irq(&zfcp_data.config_lock);
 619         list_for_each_entry(port, &adapter->port_list_head, list)
 620                 if (port->rport)
 621                         port->rport = NULL;
 622         read_unlock_irq(&zfcp_data.config_lock);
 623         fc_remove_host(shost);
 624         scsi_remove_host(shost);
 625         scsi_host_put(shost);
 626         adapter->scsi_host = NULL;
 627         atomic_clear_mask(ZFCP_STATUS_ADAPTER_REGISTERED, &adapter->status);
 628
 629         return;
 630 }
 631
 632 /*
 633  * Support functions for FC transport class
 634  */
 635 static struct fc_host_statistics*
 636 zfcp_init_fc_host_stats(struct zfcp_adapter *adapter)
 637 {
 638         struct fc_host_statistics *fc_stats;
 639
 640         if (!adapter->fc_stats) {
 641                 fc_stats = kmalloc(sizeof(*fc_stats), GFP_KERNEL);
 642                 if (!fc_stats)
 643                         return NULL;
 644                 adapter->fc_stats = fc_stats; /* freed in adater_dequeue */
 645         }
 646         memset(adapter->fc_stats, 0, sizeof(*adapter->fc_stats));
 647         return adapter->fc_stats;
 648 }
 649
 650 static void
 651 zfcp_adjust_fc_host_stats(struct fc_host_statistics *fc_stats,
 652                           struct fsf_qtcb_bottom_port *data,
 653                           struct fsf_qtcb_bottom_port *old)
 654 {
 655         fc_stats->seconds_since_last_reset = data->seconds_since_last_reset -
 656                 old->seconds_since_last_reset;
 657         fc_stats->tx_frames = data->tx_frames - old->tx_frames;
 658         fc_stats->tx_words = data->tx_words - old->tx_words;
 659         fc_stats->rx_frames = data->rx_frames - old->rx_frames;
 660         fc_stats->rx_words = data->rx_words - old->rx_words;
 661         fc_stats->lip_count = data->lip - old->lip;
 662         fc_stats->nos_count = data->nos - old->nos;
 663         fc_stats->error_frames = data->error_frames - old->error_frames;
 664         fc_stats->dumped_frames = data->dumped_frames - old->dumped_frames;
 665         fc_stats->link_failure_count = data->link_failure - old->link_failure;
 666         fc_stats->loss_of_sync_count = data->loss_of_sync - old->loss_of_sync;
 667         fc_stats->loss_of_signal_count = data->loss_of_signal -
 668                 old->loss_of_signal;
 669         fc_stats->prim_seq_protocol_err_count = data->psp_error_counts -
 670                 old->psp_error_counts;
 671         fc_stats->invalid_tx_word_count = data->invalid_tx_words -
 672                 old->invalid_tx_words;
 673         fc_stats->invalid_crc_count = data->invalid_crcs - old->invalid_crcs;
 674         fc_stats->fcp_input_requests = data->input_requests -
 675                 old->input_requests;
 676         fc_stats->fcp_output_requests = data->output_requests -
 677                 old->output_requests;
 678         fc_stats->fcp_control_requests = data->control_requests -
 679                 old->control_requests;
 680         fc_stats->fcp_input_megabytes = data->input_mb - old->input_mb;
 681         fc_stats->fcp_output_megabytes = data->output_mb - old->output_mb;
 682 }
 683
 684 static void
 685 zfcp_set_fc_host_stats(struct fc_host_statistics *fc_stats,
 686                        struct fsf_qtcb_bottom_port *data)
 687 {
 688         fc_stats->seconds_since_last_reset = data->seconds_since_last_reset;
 689         fc_stats->tx_frames = data->tx_frames;
 690         fc_stats->tx_words = data->tx_words;
 691         fc_stats->rx_frames = data->rx_frames;
 692         fc_stats->rx_words = data->rx_words;
 693         fc_stats->lip_count = data->lip;
 694         fc_stats->nos_count = data->nos;
 695         fc_stats->error_frames = data->error_frames;
 696         fc_stats->dumped_frames = data->dumped_frames;
 697         fc_stats->link_failure_count = data->link_failure;
 698         fc_stats->loss_of_sync_count = data->loss_of_sync;
 699         fc_stats->loss_of_signal_count = data->loss_of_signal;
 700         fc_stats->prim_seq_protocol_err_count = data->psp_error_counts;
 701         fc_stats->invalid_tx_word_count = data->invalid_tx_words;
 702         fc_stats->invalid_crc_count = data->invalid_crcs;
 703         fc_stats->fcp_input_requests = data->input_requests;
 704         fc_stats->fcp_output_requests = data->output_requests;
 705         fc_stats->fcp_control_requests = data->control_requests;
 706         fc_stats->fcp_input_megabytes = data->input_mb;
 707         fc_stats->fcp_output_megabytes = data->output_mb;
 708 }
 709
 710 /**
 711  * zfcp_get_fc_host_stats - provide fc_host_statistics for scsi_transport_fc
 712  *
 713  * assumption: scsi_transport_fc synchronizes calls of
 714  *             get_fc_host_stats and reset_fc_host_stats
 715  *             (XXX to be checked otherwise introduce locking)
 716  */
 717 static struct fc_host_statistics *
 718 zfcp_get_fc_host_stats(struct Scsi_Host *shost)
 719 {
 720         struct zfcp_adapter *adapter;
 721         struct fc_host_statistics *fc_stats;
 722         struct fsf_qtcb_bottom_port *data;
 723         int ret;
 724
 725         adapter = (struct zfcp_adapter *)shost->hostdata[0];
 726         fc_stats = zfcp_init_fc_host_stats(adapter);
 727         if (!fc_stats)
 728                 return NULL;
 729
 730         data = kzalloc(sizeof(*data), GFP_KERNEL);
 731         if (!data)
 732                 return NULL;
 733
 734         ret = zfcp_fsf_exchange_port_data_sync(adapter, data);
 735         if (ret) {
 736                 kfree(data);
 737                 return NULL; /* XXX return zeroed fc_stats? */
 738         }
 739
 740         if (adapter->stats_reset &&
 741             ((jiffies/HZ - adapter->stats_reset) <
 742              data->seconds_since_last_reset)) {
 743                 zfcp_adjust_fc_host_stats(fc_stats, data,
 744                                           adapter->stats_reset_data);
 745         } else
 746                 zfcp_set_fc_host_stats(fc_stats, data);
 747
 748         kfree(data);
 749         return fc_stats;
 750 }
 751
 752 static void
 753 zfcp_reset_fc_host_stats(struct Scsi_Host *shost)
 754 {
 755         struct zfcp_adapter *adapter;
 756         struct fsf_qtcb_bottom_port *data, *old_data;
 757         int ret;
 758
 759         adapter = (struct zfcp_adapter *)shost->hostdata[0];
 760         data = kzalloc(sizeof(*data), GFP_KERNEL);
 761         if (!data)
 762                 return;
 763
 764         ret = zfcp_fsf_exchange_port_data_sync(adapter, data);
 765         if (ret) {
 766                 kfree(data);
 767         } else {
 768                 adapter->stats_reset = jiffies/HZ;
 769                 old_data = adapter->stats_reset_data;
 770                 adapter->stats_reset_data = data; /* finally freed in
 771                                                      adater_dequeue */
 772                 kfree(old_data);
 773         }
 774 }
 775
 776 static void zfcp_set_rport_dev_loss_tmo(struct fc_rport *rport, u32 timeout)
 777 {
 778         rport->dev_loss_tmo = timeout;
 779 }
 780
 781 struct fc_function_template zfcp_transport_functions = {
 782         .show_starget_port_id = 1,
 783         .show_starget_port_name = 1,
 784         .show_starget_node_name = 1,
 785         .show_rport_supported_classes = 1,
 786         .show_rport_maxframe_size = 1,
 787         .show_rport_dev_loss_tmo = 1,
 788         .show_host_node_name = 1,
 789         .show_host_port_name = 1,
 790         .show_host_permanent_port_name = 1,
 791         .show_host_supported_classes = 1,
 792         .show_host_supported_speeds = 1,
 793         .show_host_maxframe_size = 1,
 794         .show_host_serial_number = 1,
 795         .get_fc_host_stats = zfcp_get_fc_host_stats,
 796         .reset_fc_host_stats = zfcp_reset_fc_host_stats,
 797         .set_rport_dev_loss_tmo = zfcp_set_rport_dev_loss_tmo,
 798         /* no functions registered for following dynamic attributes but
 799            directly set by LLDD */
 800         .show_host_port_type = 1,
 801         .show_host_speed = 1,
 802         .show_host_port_id = 1,
 803         .disable_target_scan = 1,
 804 };
 805
 806 /**
 807  * ZFCP_DEFINE_SCSI_ATTR
 808  * @_name:   name of show attribute
 809  * @_format: format string
 810  * @_value:  value to print
 811  *
 812  * Generates attribute for a unit.
 813  */
 814 #define ZFCP_DEFINE_SCSI_ATTR(_name, _format, _value)                    \
 815 static ssize_t zfcp_sysfs_scsi_##_name##_show(struct device *dev, struct device_attribute *attr,        \
 816                                               char *buf)                 \
 817 {                                                                        \
 818         struct scsi_device *sdev;                                        \
 819         struct zfcp_unit *unit;                                          \
 820                                                                          \
 821         sdev = to_scsi_device(dev);                                      \
 822         unit = sdev->hostdata;                                           \
 823         return sprintf(buf, _format, _value);                            \
 824 }                                                                        \
 825                                                                          \
 826 static DEVICE_ATTR(_name, S_IRUGO, zfcp_sysfs_scsi_##_name##_show, NULL);
 827
 828 ZFCP_DEFINE_SCSI_ATTR(hba_id, "%s\n", zfcp_get_busid_by_unit(unit));
 829 ZFCP_DEFINE_SCSI_ATTR(wwpn, "0x%016llx\n", unit->port->wwpn);
 830 ZFCP_DEFINE_SCSI_ATTR(fcp_lun, "0x%016llx\n", unit->fcp_lun);
 831
 832 static struct device_attribute *zfcp_sysfs_sdev_attrs[] = {
 833         &dev_attr_fcp_lun,
 834         &dev_attr_wwpn,
 835         &dev_attr_hba_id,
 836         NULL
 837 };
 838
 839 #undef ZFCP_LOG_AREA