drivers/s390/scsi/zfcp_scsi.c

   1 /*
   2  *
   3  * linux/drivers/s390/scsi/zfcp_scsi.c
   4  *
   5  * FCP adapter driver for IBM eServer zSeries
   6  *
   7  * (C) Copyright IBM Corp. 2002, 2004
   8  *
   9  * Author(s): Martin Peschke <mpeschke@de.ibm.com>
  10  *            Raimund Schroeder <raimund.schroeder@de.ibm.com>
  11  *            Aron Zeh
  12  *            Wolfgang Taphorn
  13  *            Stefan Bader <stefan.bader@de.ibm.com>
  14  *            Heiko Carstens <heiko.carstens@de.ibm.com>
  15  *            Andreas Herrmann <aherrman@de.ibm.com>
  16  *
  17  * This program is free software; you can redistribute it and/or modify
  18  * it under the terms of the GNU General Public License as published by
  19  * the Free Software Foundation; either version 2, or (at your option)
  20  * any later version.
  21  *
  22  * This program is distributed in the hope that it will be useful,
  23  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  24  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  25  * GNU General Public License for more details.
  26  *
  27  * You should have received a copy of the GNU General Public License
  28  * along with this program; if not, write to the Free Software
  29  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  30  */
  31
  32 #define ZFCP_LOG_AREA                   ZFCP_LOG_AREA_SCSI
  33
  34 #include "zfcp_ext.h"
  35
  36 static void zfcp_scsi_slave_destroy(struct scsi_device *sdp);
  37 static int zfcp_scsi_slave_alloc(struct scsi_device *sdp);
  38 static int zfcp_scsi_slave_configure(struct scsi_device *sdp);
  39 static int zfcp_scsi_queuecommand(struct scsi_cmnd *,
  40                                   void (*done) (struct scsi_cmnd *));
  41 static int zfcp_scsi_eh_abort_handler(struct scsi_cmnd *);
  42 static int zfcp_scsi_eh_device_reset_handler(struct scsi_cmnd *);
  43 static int zfcp_scsi_eh_bus_reset_handler(struct scsi_cmnd *);
  44 static int zfcp_scsi_eh_host_reset_handler(struct scsi_cmnd *);
  45 static int zfcp_task_management_function(struct zfcp_unit *, u8,
  46                                          struct scsi_cmnd *);
  47
  48 static struct zfcp_unit *zfcp_unit_lookup(struct zfcp_adapter *, int, scsi_id_t,
  49                                           scsi_lun_t);
  50
  51 static struct device_attribute *zfcp_sysfs_sdev_attrs[];
  52
  53 struct scsi_transport_template *zfcp_transport_template;
  54
  55 struct zfcp_data zfcp_data = {
  56         .scsi_host_template = {
  57               name:                    ZFCP_NAME,
  58               proc_name:               "zfcp",
  59               proc_info:               NULL,
  60               detect:                  NULL,
  61               slave_alloc:             zfcp_scsi_slave_alloc,
  62               slave_configure:         zfcp_scsi_slave_configure,
  63               slave_destroy:           zfcp_scsi_slave_destroy,
  64               queuecommand:            zfcp_scsi_queuecommand,
  65               eh_abort_handler:        zfcp_scsi_eh_abort_handler,
  66               eh_device_reset_handler: zfcp_scsi_eh_device_reset_handler,
  67               eh_bus_reset_handler:    zfcp_scsi_eh_bus_reset_handler,
  68               eh_host_reset_handler:   zfcp_scsi_eh_host_reset_handler,
  69                                        /* FIXME(openfcp): Tune */
  70               can_queue:               4096,
  71               this_id:                 0,
  72               /*
  73                * FIXME:
  74                * one less? can zfcp_create_sbale cope with it?
  75                */
  76               sg_tablesize:            ZFCP_MAX_SBALES_PER_REQ,
  77               cmd_per_lun:             1,
  78               unchecked_isa_dma:       0,
  79               use_clustering:          1,
  80               sdev_attrs:              zfcp_sysfs_sdev_attrs,
  81         },
  82         .driver_version = ZFCP_VERSION,
  83         /* rest initialised with zeros */
  84 };
  85
  86 /* Find start of Response Information in FCP response unit*/
  87 char *
  88 zfcp_get_fcp_rsp_info_ptr(struct fcp_rsp_iu *fcp_rsp_iu)
  89 {
  90         char *fcp_rsp_info_ptr;
  91
  92         fcp_rsp_info_ptr =
  93             (unsigned char *) fcp_rsp_iu + (sizeof (struct fcp_rsp_iu));
  94
  95         return fcp_rsp_info_ptr;
  96 }
  97
  98 /* Find start of Sense Information in FCP response unit*/
  99 char *
 100 zfcp_get_fcp_sns_info_ptr(struct fcp_rsp_iu *fcp_rsp_iu)
 101 {
 102         char *fcp_sns_info_ptr;
 103
 104         fcp_sns_info_ptr =
 105             (unsigned char *) fcp_rsp_iu + (sizeof (struct fcp_rsp_iu));
 106         if (fcp_rsp_iu->validity.bits.fcp_rsp_len_valid)
 107                 fcp_sns_info_ptr = (char *) fcp_sns_info_ptr +
 108                     fcp_rsp_iu->fcp_rsp_len;
 109
 110         return fcp_sns_info_ptr;
 111 }
 112
 113 fcp_dl_t *
 114 zfcp_get_fcp_dl_ptr(struct fcp_cmnd_iu * fcp_cmd)
 115 {
 116         int additional_length = fcp_cmd->add_fcp_cdb_length << 2;
 117         fcp_dl_t *fcp_dl_addr;
 118
 119         fcp_dl_addr = (fcp_dl_t *)
 120                 ((unsigned char *) fcp_cmd +
 121                  sizeof (struct fcp_cmnd_iu) + additional_length);
 122         /*
 123          * fcp_dl_addr = start address of fcp_cmnd structure +
 124          * size of fixed part + size of dynamically sized add_dcp_cdb field
 125          * SEE FCP-2 documentation
 126          */
 127         return fcp_dl_addr;
 128 }
 129
 130 fcp_dl_t
 131 zfcp_get_fcp_dl(struct fcp_cmnd_iu * fcp_cmd)
 132 {
 133         return *zfcp_get_fcp_dl_ptr(fcp_cmd);
 134 }
 135
 136 void
 137 zfcp_set_fcp_dl(struct fcp_cmnd_iu *fcp_cmd, fcp_dl_t fcp_dl)
 138 {
 139         *zfcp_get_fcp_dl_ptr(fcp_cmd) = fcp_dl;
 140 }
 141
 142 /*
 143  * note: it's a bit-or operation not an assignment
 144  * regarding the specified byte
 145  */
 146 static inline void
 147 set_byte(u32 * result, char status, char pos)
 148 {
 149         *result |= status << (pos * 8);
 150 }
 151
 152 void
 153 set_host_byte(u32 * result, char status)
 154 {
 155         set_byte(result, status, 2);
 156 }
 157
 158 void
 159 set_driver_byte(u32 * result, char status)
 160 {
 161         set_byte(result, status, 3);
 162 }
 163
 164 /*
 165  * function:    zfcp_scsi_slave_alloc
 166  *
 167  * purpose:
 168  *
 169  * returns:
 170  */
 171
 172 static int
 173 zfcp_scsi_slave_alloc(struct scsi_device *sdp)
 174 {
 175         struct zfcp_adapter *adapter;
 176         struct zfcp_unit *unit;
 177         unsigned long flags;
 178         int retval = -ENXIO;
 179
 180         adapter = (struct zfcp_adapter *) sdp->host->hostdata[0];
 181         if (!adapter)
 182                 goto out;
 183
 184         read_lock_irqsave(&zfcp_data.config_lock, flags);
 185         unit = zfcp_unit_lookup(adapter, sdp->channel, sdp->id, sdp->lun);
 186         if (unit) {
 187                 sdp->hostdata = unit;
 188                 unit->device = sdp;
 189                 zfcp_unit_get(unit);
 190                 retval = 0;
 191         }
 192         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
 193  out:
 194         return retval;
 195 }
 196
 197 /*
 198  * function:    zfcp_scsi_slave_destroy
 199  *
 200  * purpose:
 201  *
 202  * returns:
 203  */
 204
 205 static void
 206 zfcp_scsi_slave_destroy(struct scsi_device *sdpnt)
 207 {
 208         struct zfcp_unit *unit = (struct zfcp_unit *) sdpnt->hostdata;
 209
 210         if (unit) {
 211                 sdpnt->hostdata = NULL;
 212                 unit->device = NULL;
 213                 zfcp_unit_put(unit);
 214         } else {
 215                 ZFCP_LOG_NORMAL("bug: no unit associated with SCSI device at "
 216                                 "address %p\n", sdpnt);
 217         }
 218 }
 219
 220 /*
 221  * called from scsi midlayer to allow finetuning of a device.
 222  */
 223 static int
 224 zfcp_scsi_slave_configure(struct scsi_device *sdp)
 225 {
 226         if (sdp->tagged_supported)
 227                 scsi_adjust_queue_depth(sdp, MSG_SIMPLE_TAG, ZFCP_CMND_PER_LUN);
 228         else
 229                 scsi_adjust_queue_depth(sdp, 0, 1);
 230         return 0;
 231 }
 232
 233 /**
 234  * zfcp_scsi_command_fail - set result in scsi_cmnd and call scsi_done function
 235  * @scpnt: pointer to struct scsi_cmnd where result is set
 236  * @result: result to be set in scpnt (e.g. DID_ERROR)
 237  */
 238 static void
 239 zfcp_scsi_command_fail(struct scsi_cmnd *scpnt, int result)
 240 {
 241         set_host_byte(&scpnt->result, result);
 242         if ((scpnt->device != NULL) && (scpnt->device->host != NULL))
 243                 zfcp_scsi_dbf_event_result("fail", 4,
 244                         (struct zfcp_adapter*) scpnt->device->host->hostdata[0],
 245                         scpnt, NULL);
 246         /* return directly */
 247         scpnt->scsi_done(scpnt);
 248 }
 249
 250 /**
 251  * zfcp_scsi_command_async - worker for zfcp_scsi_queuecommand and
 252  *      zfcp_scsi_command_sync
 253  * @adapter: adapter where scsi command is issued
 254  * @unit: unit to which scsi command is sent
 255  * @scpnt: scsi command to be sent
 256  * @timer: timer to be started if request is successfully initiated
 257  *
 258  * Note: In scsi_done function must be set in scpnt.
 259  */
 260 int
 261 zfcp_scsi_command_async(struct zfcp_adapter *adapter, struct zfcp_unit *unit,
 262                         struct scsi_cmnd *scpnt, struct timer_list *timer)
 263 {
 264         int tmp;
 265         int retval;
 266
 267         retval = 0;
 268
 269         BUG_ON((adapter == NULL) || (adapter != unit->port->adapter));
 270         BUG_ON(scpnt->scsi_done == NULL);
 271
 272         if (unlikely(NULL == unit)) {
 273                 zfcp_scsi_command_fail(scpnt, DID_NO_CONNECT);
 274                 goto out;
 275         }
 276
 277         if (unlikely(
 278               atomic_test_mask(ZFCP_STATUS_COMMON_ERP_FAILED, &unit->status) ||
 279              !atomic_test_mask(ZFCP_STATUS_COMMON_RUNNING, &unit->status))) {
 280                 ZFCP_LOG_DEBUG("stopping SCSI I/O on unit 0x%016Lx on port "
 281                                "0x%016Lx on adapter %s\n",
 282                                unit->fcp_lun, unit->port->wwpn,
 283                                zfcp_get_busid_by_adapter(adapter));
 284                 zfcp_scsi_command_fail(scpnt, DID_ERROR);
 285                 goto out;
 286         }
 287
 288         if (unlikely(
 289              !atomic_test_mask(ZFCP_STATUS_COMMON_UNBLOCKED, &unit->status))) {
 290                 ZFCP_LOG_DEBUG("adapter %s not ready or unit 0x%016Lx "
 291                                "on port 0x%016Lx in recovery\n",
 292                                zfcp_get_busid_by_unit(unit),
 293                                unit->fcp_lun, unit->port->wwpn);
 294                 retval = SCSI_MLQUEUE_DEVICE_BUSY;
 295                 goto out;
 296         }
 297
 298         tmp = zfcp_fsf_send_fcp_command_task(adapter, unit, scpnt, timer,
 299                                              ZFCP_REQ_AUTO_CLEANUP);
 300
 301         if (unlikely(tmp < 0)) {
 302                 ZFCP_LOG_DEBUG("error: initiation of Send FCP Cmnd failed\n");
 303                 retval = SCSI_MLQUEUE_HOST_BUSY;
 304         }
 305
 306 out:
 307         return retval;
 308 }
 309
 310 void
 311 zfcp_scsi_command_sync_handler(struct scsi_cmnd *scpnt)
 312 {
 313         struct completion *wait = (struct completion *) scpnt->SCp.ptr;
 314         complete(wait);
 315 }
 316
 317
 318 /**
 319  * zfcp_scsi_command_sync - send a SCSI command and wait for completion
 320  * @unit: unit where command is sent to
 321  * @scpnt: scsi command to be sent
 322  * @timer: timer to be started if request is successfully initiated
 323  * Return: 0
 324  *
 325  * Errors are indicated in scpnt->result
 326  */
 327 int
 328 zfcp_scsi_command_sync(struct zfcp_unit *unit, struct scsi_cmnd *scpnt,
 329                        struct timer_list *timer)
 330 {
 331         int ret;
 332         DECLARE_COMPLETION(wait);
 333
 334         scpnt->SCp.ptr = (void *) &wait;  /* silent re-use */
 335         scpnt->scsi_done = zfcp_scsi_command_sync_handler;
 336         ret = zfcp_scsi_command_async(unit->port->adapter, unit, scpnt, timer);
 337         if (ret == 0)
 338                 wait_for_completion(&wait);
 339
 340         scpnt->SCp.ptr = NULL;
 341
 342         return 0;
 343 }
 344
 345 /*
 346  * function:    zfcp_scsi_queuecommand
 347  *
 348  * purpose:     enqueues a SCSI command to the specified target device
 349  *
 350  * returns:     0 - success, SCSI command enqueued
 351  *              !0 - failure
 352  */
 353 int
 354 zfcp_scsi_queuecommand(struct scsi_cmnd *scpnt,
 355                        void (*done) (struct scsi_cmnd *))
 356 {
 357         struct zfcp_unit *unit;
 358         struct zfcp_adapter *adapter;
 359
 360         /* reset the status for this request */
 361         scpnt->result = 0;
 362         scpnt->host_scribble = NULL;
 363         scpnt->scsi_done = done;
 364
 365         /*
 366          * figure out adapter and target device
 367          * (stored there by zfcp_scsi_slave_alloc)
 368          */
 369         adapter = (struct zfcp_adapter *) scpnt->device->host->hostdata[0];
 370         unit = (struct zfcp_unit *) scpnt->device->hostdata;
 371
 372         return zfcp_scsi_command_async(adapter, unit, scpnt, NULL);
 373 }
 374
 375 /*
 376  * function:    zfcp_unit_lookup
 377  *
 378  * purpose:
 379  *
 380  * returns:
 381  *
 382  * context:
 383  */
 384 static struct zfcp_unit *
 385 zfcp_unit_lookup(struct zfcp_adapter *adapter, int channel, scsi_id_t id,
 386                  scsi_lun_t lun)
 387 {
 388         struct zfcp_port *port;
 389         struct zfcp_unit *unit, *retval = NULL;
 390
 391         list_for_each_entry(port, &adapter->port_list_head, list) {
 392                 if (!port->rport || (id != port->rport->scsi_target_id))
 393                         continue;
 394                 list_for_each_entry(unit, &port->unit_list_head, list) {
 395                         if (lun == unit->scsi_lun) {
 396                                 retval = unit;
 397                                 goto out;
 398                         }
 399                 }
 400         }
 401  out:
 402         return retval;
 403 }
 404
 405 /**
 406  * zfcp_scsi_eh_abort_handler - abort the specified SCSI command
 407  * @scpnt: pointer to scsi_cmnd to be aborted
 408  * Return: SUCCESS - command has been aborted and cleaned up in internal
 409  *          bookkeeping, SCSI stack won't be called for aborted command
 410  *         FAILED - otherwise
 411  *
 412  * We do not need to care for a SCSI command which completes normally
 413  * but late during this abort routine runs.  We are allowed to return
 414  * late commands to the SCSI stack.  It tracks the state of commands and
 415  * will handle late commands.  (Usually, the normal completion of late
 416  * commands is ignored with respect to the running abort operation.)
 417  */
 418 int
 419 zfcp_scsi_eh_abort_handler(struct scsi_cmnd *scpnt)
 420 {
 421         struct Scsi_Host *scsi_host;
 422         struct zfcp_adapter *adapter;
 423         struct zfcp_unit *unit;
 424         int retval = SUCCESS;
 425         struct zfcp_fsf_req *new_fsf_req = NULL;
 426         struct zfcp_fsf_req *old_fsf_req;
 427         unsigned long flags;
 428
 429         scsi_host = scpnt->device->host;
 430         adapter = (struct zfcp_adapter *) scsi_host->hostdata[0];
 431         unit = (struct zfcp_unit *) scpnt->device->hostdata;
 432
 433         ZFCP_LOG_INFO("aborting scsi_cmnd=%p on adapter %s\n",
 434                       scpnt, zfcp_get_busid_by_adapter(adapter));
 435
 436         /* avoid race condition between late normal completion and abort */
 437         write_lock_irqsave(&adapter->abort_lock, flags);
 438
 439         /*
 440          * Check whether command has just completed and can not be aborted.
 441          * Even if the command has just been completed late, we can access
 442          * scpnt since the SCSI stack does not release it at least until
 443          * this routine returns. (scpnt is parameter passed to this routine
 444          * and must not disappear during abort even on late completion.)
 445          */
 446         old_fsf_req = (struct zfcp_fsf_req *) scpnt->host_scribble;
 447         if (!old_fsf_req) {
 448                 write_unlock_irqrestore(&adapter->abort_lock, flags);
 449                 zfcp_scsi_dbf_event_abort("lte1", adapter, scpnt, NULL, NULL);
 450                 retval = SUCCESS;
 451                 goto out;
 452         }
 453         old_fsf_req->data = 0;
 454         old_fsf_req->status |= ZFCP_STATUS_FSFREQ_ABORTING;
 455
 456         /* don't access old_fsf_req after releasing the abort_lock */
 457         write_unlock_irqrestore(&adapter->abort_lock, flags);
 458         /* call FSF routine which does the abort */
 459         new_fsf_req = zfcp_fsf_abort_fcp_command((unsigned long) old_fsf_req,
 460                                                  adapter, unit, 0);
 461         if (!new_fsf_req) {
 462                 ZFCP_LOG_INFO("error: initiation of Abort FCP Cmnd failed\n");
 463                 zfcp_scsi_dbf_event_abort("nres", adapter, scpnt, NULL,
 464                                           old_fsf_req);
 465                 retval = FAILED;
 466                 goto out;
 467         }
 468
 469         /* wait for completion of abort */
 470         __wait_event(new_fsf_req->completion_wq,
 471                      new_fsf_req->status & ZFCP_STATUS_FSFREQ_COMPLETED);
 472
 473         /* status should be valid since signals were not permitted */
 474         if (new_fsf_req->status & ZFCP_STATUS_FSFREQ_ABORTSUCCEEDED) {
 475                 zfcp_scsi_dbf_event_abort("okay", adapter, scpnt, new_fsf_req,
 476                                           NULL);
 477                 retval = SUCCESS;
 478         } else if (new_fsf_req->status & ZFCP_STATUS_FSFREQ_ABORTNOTNEEDED) {
 479                 zfcp_scsi_dbf_event_abort("lte2", adapter, scpnt, new_fsf_req,
 480                                           NULL);
 481                 retval = SUCCESS;
 482         } else {
 483                 zfcp_scsi_dbf_event_abort("fail", adapter, scpnt, new_fsf_req,
 484                                           NULL);
 485                 retval = FAILED;
 486         }
 487         zfcp_fsf_req_free(new_fsf_req);
 488  out:
 489         return retval;
 490 }
 491
 492 /*
 493  * function:    zfcp_scsi_eh_device_reset_handler
 494  *
 495  * purpose:
 496  *
 497  * returns:
 498  */
 499 int
 500 zfcp_scsi_eh_device_reset_handler(struct scsi_cmnd *scpnt)
 501 {
 502         int retval;
 503         struct zfcp_unit *unit = (struct zfcp_unit *) scpnt->device->hostdata;
 504
 505         if (!unit) {
 506                 ZFCP_LOG_NORMAL("bug: Tried reset for nonexistent unit\n");
 507                 retval = SUCCESS;
 508                 goto out;
 509         }
 510         ZFCP_LOG_NORMAL("resetting unit 0x%016Lx\n", unit->fcp_lun);
 511
 512         /*
 513          * If we do not know whether the unit supports 'logical unit reset'
 514          * then try 'logical unit reset' and proceed with 'target reset'
 515          * if 'logical unit reset' fails.
 516          * If the unit is known not to support 'logical unit reset' then
 517          * skip 'logical unit reset' and try 'target reset' immediately.
 518          */
 519         if (!atomic_test_mask(ZFCP_STATUS_UNIT_NOTSUPPUNITRESET,
 520                               &unit->status)) {
 521                 retval = zfcp_task_management_function(unit,
 522                                                        FCP_LOGICAL_UNIT_RESET,
 523                                                        scpnt);
 524                 if (retval) {
 525                         ZFCP_LOG_DEBUG("unit reset failed (unit=%p)\n", unit);
 526                         if (retval == -ENOTSUPP)
 527                                 atomic_set_mask
 528                                     (ZFCP_STATUS_UNIT_NOTSUPPUNITRESET,
 529                                      &unit->status);
 530                         /* fall through and try 'target reset' next */
 531                 } else {
 532                         ZFCP_LOG_DEBUG("unit reset succeeded (unit=%p)\n",
 533                                        unit);
 534                         /* avoid 'target reset' */
 535                         retval = SUCCESS;
 536                         goto out;
 537                 }
 538         }
 539         retval = zfcp_task_management_function(unit, FCP_TARGET_RESET, scpnt);
 540         if (retval) {
 541                 ZFCP_LOG_DEBUG("target reset failed (unit=%p)\n", unit);
 542                 retval = FAILED;
 543         } else {
 544                 ZFCP_LOG_DEBUG("target reset succeeded (unit=%p)\n", unit);
 545                 retval = SUCCESS;
 546         }
 547  out:
 548         return retval;
 549 }
 550
 551 static int
 552 zfcp_task_management_function(struct zfcp_unit *unit, u8 tm_flags,
 553                               struct scsi_cmnd *scpnt)
 554 {
 555         struct zfcp_adapter *adapter = unit->port->adapter;
 556         struct zfcp_fsf_req *fsf_req;
 557         int retval = 0;
 558
 559         /* issue task management function */
 560         fsf_req = zfcp_fsf_send_fcp_command_task_management
 561                 (adapter, unit, tm_flags, 0);
 562         if (!fsf_req) {
 563                 ZFCP_LOG_INFO("error: creation of task management request "
 564                               "failed for unit 0x%016Lx on port 0x%016Lx on  "
 565                               "adapter %s\n", unit->fcp_lun, unit->port->wwpn,
 566                               zfcp_get_busid_by_adapter(adapter));
 567                 zfcp_scsi_dbf_event_devreset("nres", tm_flags, unit, scpnt);
 568                 retval = -ENOMEM;
 569                 goto out;
 570         }
 571
 572         __wait_event(fsf_req->completion_wq,
 573                      fsf_req->status & ZFCP_STATUS_FSFREQ_COMPLETED);
 574
 575         /*
 576          * check completion status of task management function
 577          */
 578         if (fsf_req->status & ZFCP_STATUS_FSFREQ_TMFUNCFAILED) {
 579                 zfcp_scsi_dbf_event_devreset("fail", tm_flags, unit, scpnt);
 580                 retval = -EIO;
 581         } else if (fsf_req->status & ZFCP_STATUS_FSFREQ_TMFUNCNOTSUPP) {
 582                 zfcp_scsi_dbf_event_devreset("nsup", tm_flags, unit, scpnt);
 583                 retval = -ENOTSUPP;
 584         } else
 585                 zfcp_scsi_dbf_event_devreset("okay", tm_flags, unit, scpnt);
 586
 587         zfcp_fsf_req_free(fsf_req);
 588  out:
 589         return retval;
 590 }
 591
 592 /**
 593  * zfcp_scsi_eh_bus_reset_handler - reset bus (reopen adapter)
 594  */
 595 int
 596 zfcp_scsi_eh_bus_reset_handler(struct scsi_cmnd *scpnt)
 597 {
 598         struct zfcp_unit *unit = (struct zfcp_unit*) scpnt->device->hostdata;
 599         struct zfcp_adapter *adapter = unit->port->adapter;
 600
 601         ZFCP_LOG_NORMAL("bus reset because of problems with "
 602                         "unit 0x%016Lx\n", unit->fcp_lun);
 603         zfcp_erp_adapter_reopen(adapter, 0);
 604         zfcp_erp_wait(adapter);
 605
 606         return SUCCESS;
 607 }
 608
 609 /**
 610  * zfcp_scsi_eh_host_reset_handler - reset host (reopen adapter)
 611  */
 612 int
 613 zfcp_scsi_eh_host_reset_handler(struct scsi_cmnd *scpnt)
 614 {
 615         struct zfcp_unit *unit = (struct zfcp_unit*) scpnt->device->hostdata;
 616         struct zfcp_adapter *adapter = unit->port->adapter;
 617
 618         ZFCP_LOG_NORMAL("host reset because of problems with "
 619                         "unit 0x%016Lx\n", unit->fcp_lun);
 620         zfcp_erp_adapter_reopen(adapter, 0);
 621         zfcp_erp_wait(adapter);
 622
 623         return SUCCESS;
 624 }
 625
 626 /*
 627  * function:
 628  *
 629  * purpose:
 630  *
 631  * returns:
 632  */
 633 int
 634 zfcp_adapter_scsi_register(struct zfcp_adapter *adapter)
 635 {
 636         int retval = 0;
 637         static unsigned int unique_id = 0;
 638
 639         /* register adapter as SCSI host with mid layer of SCSI stack */
 640         adapter->scsi_host = scsi_host_alloc(&zfcp_data.scsi_host_template,
 641                                              sizeof (struct zfcp_adapter *));
 642         if (!adapter->scsi_host) {
 643                 ZFCP_LOG_NORMAL("error: registration with SCSI stack failed "
 644                                 "for adapter %s ",
 645                                 zfcp_get_busid_by_adapter(adapter));
 646                 retval = -EIO;
 647                 goto out;
 648         }
 649         ZFCP_LOG_DEBUG("host registered, scsi_host=%p\n", adapter->scsi_host);
 650
 651         /* tell the SCSI stack some characteristics of this adapter */
 652         adapter->scsi_host->max_id = 1;
 653         adapter->scsi_host->max_lun = 1;
 654         adapter->scsi_host->max_channel = 0;
 655         adapter->scsi_host->unique_id = unique_id++;    /* FIXME */
 656         adapter->scsi_host->max_cmd_len = ZFCP_MAX_SCSI_CMND_LENGTH;
 657         adapter->scsi_host->transportt = zfcp_transport_template;
 658         /*
 659          * Reverse mapping of the host number to avoid race condition
 660          */
 661         adapter->scsi_host_no = adapter->scsi_host->host_no;
 662
 663         /*
 664          * save a pointer to our own adapter data structure within
 665          * hostdata field of SCSI host data structure
 666          */
 667         adapter->scsi_host->hostdata[0] = (unsigned long) adapter;
 668
 669         if (scsi_add_host(adapter->scsi_host, &adapter->ccw_device->dev)) {
 670                 scsi_host_put(adapter->scsi_host);
 671                 retval = -EIO;
 672                 goto out;
 673         }
 674         atomic_set_mask(ZFCP_STATUS_ADAPTER_REGISTERED, &adapter->status);
 675  out:
 676         return retval;
 677 }
 678
 679 /*
 680  * function:
 681  *
 682  * purpose:
 683  *
 684  * returns:
 685  */
 686 void
 687 zfcp_adapter_scsi_unregister(struct zfcp_adapter *adapter)
 688 {
 689         struct Scsi_Host *shost;
 690         struct zfcp_port *port;
 691
 692         shost = adapter->scsi_host;
 693         if (!shost)
 694                 return;
 695         read_lock_irq(&zfcp_data.config_lock);
 696         list_for_each_entry(port, &adapter->port_list_head, list)
 697                 if (port->rport)
 698                         port->rport = NULL;
 699         read_unlock_irq(&zfcp_data.config_lock);
 700         fc_remove_host(shost);
 701         scsi_remove_host(shost);
 702         scsi_host_put(shost);
 703         adapter->scsi_host = NULL;
 704         adapter->scsi_host_no = 0;
 705         atomic_clear_mask(ZFCP_STATUS_ADAPTER_REGISTERED, &adapter->status);
 706
 707         return;
 708 }
 709
 710
 711 void
 712 zfcp_fsf_start_scsi_er_timer(struct zfcp_adapter *adapter)
 713 {
 714         adapter->scsi_er_timer.function = zfcp_fsf_scsi_er_timeout_handler;
 715         adapter->scsi_er_timer.data = (unsigned long) adapter;
 716         adapter->scsi_er_timer.expires = jiffies + ZFCP_SCSI_ER_TIMEOUT;
 717         add_timer(&adapter->scsi_er_timer);
 718 }
 719
 720 /*
 721  * Support functions for FC transport class
 722  */
 723 static struct fc_host_statistics*
 724 zfcp_init_fc_host_stats(struct zfcp_adapter *adapter)
 725 {
 726         struct fc_host_statistics *fc_stats;
 727
 728         if (!adapter->fc_stats) {
 729                 fc_stats = kmalloc(sizeof(*fc_stats), GFP_KERNEL);
 730                 if (!fc_stats)
 731                         return NULL;
 732                 adapter->fc_stats = fc_stats; /* freed in adater_dequeue */
 733         }
 734         memset(adapter->fc_stats, 0, sizeof(*adapter->fc_stats));
 735         return adapter->fc_stats;
 736 }
 737
 738 static void
 739 zfcp_adjust_fc_host_stats(struct fc_host_statistics *fc_stats,
 740                           struct fsf_qtcb_bottom_port *data,
 741                           struct fsf_qtcb_bottom_port *old)
 742 {
 743         fc_stats->seconds_since_last_reset = data->seconds_since_last_reset -
 744                 old->seconds_since_last_reset;
 745         fc_stats->tx_frames = data->tx_frames - old->tx_frames;
 746         fc_stats->tx_words = data->tx_words - old->tx_words;
 747         fc_stats->rx_frames = data->rx_frames - old->rx_frames;
 748         fc_stats->rx_words = data->rx_words - old->rx_words;
 749         fc_stats->lip_count = data->lip - old->lip;
 750         fc_stats->nos_count = data->nos - old->nos;
 751         fc_stats->error_frames = data->error_frames - old->error_frames;
 752         fc_stats->dumped_frames = data->dumped_frames - old->dumped_frames;
 753         fc_stats->link_failure_count = data->link_failure - old->link_failure;
 754         fc_stats->loss_of_sync_count = data->loss_of_sync - old->loss_of_sync;
 755         fc_stats->loss_of_signal_count = data->loss_of_signal -
 756                 old->loss_of_signal;
 757         fc_stats->prim_seq_protocol_err_count = data->psp_error_counts -
 758                 old->psp_error_counts;
 759         fc_stats->invalid_tx_word_count = data->invalid_tx_words -
 760                 old->invalid_tx_words;
 761         fc_stats->invalid_crc_count = data->invalid_crcs - old->invalid_crcs;
 762         fc_stats->fcp_input_requests = data->input_requests -
 763                 old->input_requests;
 764         fc_stats->fcp_output_requests = data->output_requests -
 765                 old->output_requests;
 766         fc_stats->fcp_control_requests = data->control_requests -
 767                 old->control_requests;
 768         fc_stats->fcp_input_megabytes = data->input_mb - old->input_mb;
 769         fc_stats->fcp_output_megabytes = data->output_mb - old->output_mb;
 770 }
 771
 772 static void
 773 zfcp_set_fc_host_stats(struct fc_host_statistics *fc_stats,
 774                        struct fsf_qtcb_bottom_port *data)
 775 {
 776         fc_stats->seconds_since_last_reset = data->seconds_since_last_reset;
 777         fc_stats->tx_frames = data->tx_frames;
 778         fc_stats->tx_words = data->tx_words;
 779         fc_stats->rx_frames = data->rx_frames;
 780         fc_stats->rx_words = data->rx_words;
 781         fc_stats->lip_count = data->lip;
 782         fc_stats->nos_count = data->nos;
 783         fc_stats->error_frames = data->error_frames;
 784         fc_stats->dumped_frames = data->dumped_frames;
 785         fc_stats->link_failure_count = data->link_failure;
 786         fc_stats->loss_of_sync_count = data->loss_of_sync;
 787         fc_stats->loss_of_signal_count = data->loss_of_signal;
 788         fc_stats->prim_seq_protocol_err_count = data->psp_error_counts;
 789         fc_stats->invalid_tx_word_count = data->invalid_tx_words;
 790         fc_stats->invalid_crc_count = data->invalid_crcs;
 791         fc_stats->fcp_input_requests = data->input_requests;
 792         fc_stats->fcp_output_requests = data->output_requests;
 793         fc_stats->fcp_control_requests = data->control_requests;
 794         fc_stats->fcp_input_megabytes = data->input_mb;
 795         fc_stats->fcp_output_megabytes = data->output_mb;
 796 }
 797
 798 /**
 799  * zfcp_get_fc_host_stats - provide fc_host_statistics for scsi_transport_fc
 800  *
 801  * assumption: scsi_transport_fc synchronizes calls of
 802  *             get_fc_host_stats and reset_fc_host_stats
 803  *             (XXX to be checked otherwise introduce locking)
 804  */
 805 static struct fc_host_statistics *
 806 zfcp_get_fc_host_stats(struct Scsi_Host *shost)
 807 {
 808         struct zfcp_adapter *adapter;
 809         struct fc_host_statistics *fc_stats;
 810         struct fsf_qtcb_bottom_port *data;
 811         int ret;
 812
 813         adapter = (struct zfcp_adapter *)shost->hostdata[0];
 814         fc_stats = zfcp_init_fc_host_stats(adapter);
 815         if (!fc_stats)
 816                 return NULL;
 817
 818         data = kmalloc(sizeof(*data), GFP_KERNEL);
 819         if (!data)
 820                 return NULL;
 821         memset(data, 0, sizeof(*data));
 822
 823         ret = zfcp_fsf_exchange_port_data(NULL, adapter, data);
 824         if (ret) {
 825                 kfree(data);
 826                 return NULL; /* XXX return zeroed fc_stats? */
 827         }
 828
 829         if (adapter->stats_reset &&
 830             ((jiffies/HZ - adapter->stats_reset) <
 831              data->seconds_since_last_reset)) {
 832                 zfcp_adjust_fc_host_stats(fc_stats, data,
 833                                           adapter->stats_reset_data);
 834         } else
 835                 zfcp_set_fc_host_stats(fc_stats, data);
 836
 837         kfree(data);
 838         return fc_stats;
 839 }
 840
 841 static void
 842 zfcp_reset_fc_host_stats(struct Scsi_Host *shost)
 843 {
 844         struct zfcp_adapter *adapter;
 845         struct fsf_qtcb_bottom_port *data, *old_data;
 846         int ret;
 847
 848         adapter = (struct zfcp_adapter *)shost->hostdata[0];
 849         data = kmalloc(sizeof(*data), GFP_KERNEL);
 850         if (!data)
 851                 return;
 852         memset(data, 0, sizeof(*data));
 853
 854         ret = zfcp_fsf_exchange_port_data(NULL, adapter, data);
 855         if (ret == 0) {
 856                 adapter->stats_reset = jiffies/HZ;
 857                 old_data = adapter->stats_reset_data;
 858                 adapter->stats_reset_data = data; /* finally freed in
 859                                                      adater_dequeue */
 860                 kfree(old_data);
 861         }
 862 }
 863
 864 struct fc_function_template zfcp_transport_functions = {
 865         .show_starget_port_id = 1,
 866         .show_starget_port_name = 1,
 867         .show_starget_node_name = 1,
 868         .show_rport_supported_classes = 1,
 869         .show_host_node_name = 1,
 870         .show_host_port_name = 1,
 871         .show_host_permanent_port_name = 1,
 872         .show_host_supported_classes = 1,
 873         .show_host_supported_speeds = 1,
 874         .show_host_maxframe_size = 1,
 875         .show_host_serial_number = 1,
 876         .get_fc_host_stats = zfcp_get_fc_host_stats,
 877         .reset_fc_host_stats = zfcp_reset_fc_host_stats,
 878         /* no functions registered for following dynamic attributes but
 879            directly set by LLDD */
 880         .show_host_port_type = 1,
 881         .show_host_speed = 1,
 882         .show_host_port_id = 1,
 883 };
 884
 885 /**
 886  * ZFCP_DEFINE_SCSI_ATTR
 887  * @_name:   name of show attribute
 888  * @_format: format string
 889  * @_value:  value to print
 890  *
 891  * Generates attribute for a unit.
 892  */
 893 #define ZFCP_DEFINE_SCSI_ATTR(_name, _format, _value)                    \
 894 static ssize_t zfcp_sysfs_scsi_##_name##_show(struct device *dev, struct device_attribute *attr,        \
 895                                               char *buf)                 \
 896 {                                                                        \
 897         struct scsi_device *sdev;                                        \
 898         struct zfcp_unit *unit;                                          \
 899                                                                          \
 900         sdev = to_scsi_device(dev);                                      \
 901         unit = sdev->hostdata;                                           \
 902         return sprintf(buf, _format, _value);                            \
 903 }                                                                        \
 904                                                                          \
 905 static DEVICE_ATTR(_name, S_IRUGO, zfcp_sysfs_scsi_##_name##_show, NULL);
 906
 907 ZFCP_DEFINE_SCSI_ATTR(hba_id, "%s\n", zfcp_get_busid_by_unit(unit));
 908 ZFCP_DEFINE_SCSI_ATTR(wwpn, "0x%016llx\n", unit->port->wwpn);
 909 ZFCP_DEFINE_SCSI_ATTR(fcp_lun, "0x%016llx\n", unit->fcp_lun);
 910
 911 static struct device_attribute *zfcp_sysfs_sdev_attrs[] = {
 912         &dev_attr_fcp_lun,
 913         &dev_attr_wwpn,
 914         &dev_attr_hba_id,
 915         NULL
 916 };
 917
 918 #undef ZFCP_LOG_AREA