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  *
  16  * This program is free software; you can redistribute it and/or modify
  17  * it under the terms of the GNU General Public License as published by
  18  * the Free Software Foundation; either version 2, or (at your option)
  19  * any later version.
  20  *
  21  * This program is distributed in the hope that it will be useful,
  22  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  23  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  24  * GNU General Public License for more details.
  25  *
  26  * You should have received a copy of the GNU General Public License
  27  * along with this program; if not, write to the Free Software
  28  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  29  */
  30
  31 #define ZFCP_LOG_AREA                   ZFCP_LOG_AREA_SCSI
  32
  33 /* this drivers version (do not edit !!! generated and updated by cvs) */
  34 #define ZFCP_SCSI_REVISION "$Revision: 1.62 $"
  35
  36 #include "zfcp_ext.h"
  37
  38 static void zfcp_scsi_slave_destroy(struct scsi_device *sdp);
  39 static int zfcp_scsi_slave_alloc(struct scsi_device *sdp);
  40 static int zfcp_scsi_slave_configure(struct scsi_device *sdp);
  41 static int zfcp_scsi_queuecommand(struct scsi_cmnd *,
  42                                   void (*done) (struct scsi_cmnd *));
  43 static int zfcp_scsi_eh_abort_handler(struct scsi_cmnd *);
  44 static int zfcp_scsi_eh_device_reset_handler(struct scsi_cmnd *);
  45 static int zfcp_scsi_eh_bus_reset_handler(struct scsi_cmnd *);
  46 static int zfcp_scsi_eh_host_reset_handler(struct scsi_cmnd *);
  47 static int zfcp_task_management_function(struct zfcp_unit *, u8);
  48
  49 static struct zfcp_unit *zfcp_unit_lookup(struct zfcp_adapter *, int, scsi_id_t,
  50                                           scsi_lun_t);
  51
  52 static struct device_attribute *zfcp_sysfs_sdev_attrs[];
  53
  54 struct zfcp_data zfcp_data = {
  55         .scsi_host_template = {
  56               name:                    ZFCP_NAME,
  57               proc_name:               "zfcp",
  58               proc_info:               NULL,
  59               detect:                  NULL,
  60               slave_alloc:             zfcp_scsi_slave_alloc,
  61               slave_configure:         zfcp_scsi_slave_configure,
  62               slave_destroy:           zfcp_scsi_slave_destroy,
  63               queuecommand:            zfcp_scsi_queuecommand,
  64               eh_abort_handler:        zfcp_scsi_eh_abort_handler,
  65               eh_device_reset_handler: zfcp_scsi_eh_device_reset_handler,
  66               eh_bus_reset_handler:    zfcp_scsi_eh_bus_reset_handler,
  67               eh_host_reset_handler:   zfcp_scsi_eh_host_reset_handler,
  68                                        /* FIXME(openfcp): Tune */
  69               can_queue:               4096,
  70               this_id:                 0,
  71               /*
  72                * FIXME:
  73                * one less? can zfcp_create_sbale cope with it?
  74                */
  75               sg_tablesize:            ZFCP_MAX_SBALES_PER_REQ,
  76               cmd_per_lun:             1,
  77               unchecked_isa_dma:       0,
  78               use_clustering:          1,
  79               sdev_attrs:              zfcp_sysfs_sdev_attrs,
  80         }
  81         /* rest initialised with zeros */
  82 };
  83
  84 /* Find start of Response Information in FCP response unit*/
  85 char *
  86 zfcp_get_fcp_rsp_info_ptr(struct fcp_rsp_iu *fcp_rsp_iu)
  87 {
  88         char *fcp_rsp_info_ptr;
  89
  90         fcp_rsp_info_ptr =
  91             (unsigned char *) fcp_rsp_iu + (sizeof (struct fcp_rsp_iu));
  92
  93         return fcp_rsp_info_ptr;
  94 }
  95
  96 /* Find start of Sense Information in FCP response unit*/
  97 char *
  98 zfcp_get_fcp_sns_info_ptr(struct fcp_rsp_iu *fcp_rsp_iu)
  99 {
 100         char *fcp_sns_info_ptr;
 101
 102         fcp_sns_info_ptr =
 103             (unsigned char *) fcp_rsp_iu + (sizeof (struct fcp_rsp_iu));
 104         if (fcp_rsp_iu->validity.bits.fcp_rsp_len_valid)
 105                 fcp_sns_info_ptr = (char *) fcp_sns_info_ptr +
 106                     fcp_rsp_iu->fcp_rsp_len;
 107
 108         return fcp_sns_info_ptr;
 109 }
 110
 111 fcp_dl_t *
 112 zfcp_get_fcp_dl_ptr(struct fcp_cmnd_iu * fcp_cmd)
 113 {
 114         int additional_length = fcp_cmd->add_fcp_cdb_length << 2;
 115         fcp_dl_t *fcp_dl_addr;
 116
 117         fcp_dl_addr = (fcp_dl_t *)
 118                 ((unsigned char *) fcp_cmd +
 119                  sizeof (struct fcp_cmnd_iu) + additional_length);
 120         /*
 121          * fcp_dl_addr = start address of fcp_cmnd structure +
 122          * size of fixed part + size of dynamically sized add_dcp_cdb field
 123          * SEE FCP-2 documentation
 124          */
 125         return fcp_dl_addr;
 126 }
 127
 128 fcp_dl_t
 129 zfcp_get_fcp_dl(struct fcp_cmnd_iu * fcp_cmd)
 130 {
 131         return *zfcp_get_fcp_dl_ptr(fcp_cmd);
 132 }
 133
 134 void
 135 zfcp_set_fcp_dl(struct fcp_cmnd_iu *fcp_cmd, fcp_dl_t fcp_dl)
 136 {
 137         *zfcp_get_fcp_dl_ptr(fcp_cmd) = fcp_dl;
 138 }
 139
 140 /*
 141  * note: it's a bit-or operation not an assignment
 142  * regarding the specified byte
 143  */
 144 static inline void
 145 set_byte(u32 * result, char status, char pos)
 146 {
 147         *result |= status << (pos * 8);
 148 }
 149
 150 void
 151 set_host_byte(u32 * result, char status)
 152 {
 153         set_byte(result, status, 2);
 154 }
 155
 156 void
 157 set_driver_byte(u32 * result, char status)
 158 {
 159         set_byte(result, status, 3);
 160 }
 161
 162 /*
 163  * function:    zfcp_scsi_slave_alloc
 164  *
 165  * purpose:
 166  *
 167  * returns:
 168  */
 169
 170 static int
 171 zfcp_scsi_slave_alloc(struct scsi_device *sdp)
 172 {
 173         struct zfcp_adapter *adapter;
 174         struct zfcp_unit *unit;
 175         unsigned long flags;
 176         int retval = -ENODEV;
 177
 178         adapter = (struct zfcp_adapter *) sdp->host->hostdata[0];
 179         if (!adapter)
 180                 goto out;
 181
 182         read_lock_irqsave(&zfcp_data.config_lock, flags);
 183         unit = zfcp_unit_lookup(adapter, sdp->channel, sdp->id, sdp->lun);
 184         if (unit) {
 185                 sdp->hostdata = unit;
 186                 unit->device = sdp;
 187                 zfcp_unit_get(unit);
 188                 retval = 0;
 189         }
 190         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
 191  out:
 192         return retval;
 193 }
 194
 195 /*
 196  * function:    zfcp_scsi_slave_destroy
 197  *
 198  * purpose:
 199  *
 200  * returns:
 201  */
 202
 203 static void
 204 zfcp_scsi_slave_destroy(struct scsi_device *sdpnt)
 205 {
 206         struct zfcp_unit *unit = (struct zfcp_unit *) sdpnt->hostdata;
 207
 208         if (unit) {
 209                 sdpnt->hostdata = NULL;
 210                 unit->device = NULL;
 211                 zfcp_unit_put(unit);
 212         } else {
 213                 ZFCP_LOG_NORMAL("bug: no unit associated with SCSI device at "
 214                                 "address %p\n", sdpnt);
 215         }
 216 }
 217
 218 /*
 219  * called from scsi midlayer to allow finetuning of a device.
 220  */
 221 static int
 222 zfcp_scsi_slave_configure(struct scsi_device *sdp)
 223 {
 224         if (sdp->tagged_supported)
 225                 scsi_adjust_queue_depth(sdp, MSG_SIMPLE_TAG, ZFCP_CMND_PER_LUN);
 226         else
 227                 scsi_adjust_queue_depth(sdp, 0, 1);
 228         return 0;
 229 }
 230
 231 /**
 232  * zfcp_scsi_command_fail - set result in scsi_cmnd and call scsi_done function
 233  * @scpnt: pointer to struct scsi_cmnd where result is set
 234  * @result: result to be set in scpnt (e.g. DID_ERROR)
 235  */
 236 static void
 237 zfcp_scsi_command_fail(struct scsi_cmnd *scpnt, int result)
 238 {
 239         set_host_byte(&scpnt->result, result);
 240         zfcp_cmd_dbf_event_scsi("failing", scpnt);
 241         /* return directly */
 242         scpnt->scsi_done(scpnt);
 243 }
 244
 245 /**
 246  * zfcp_scsi_command_async - worker for zfcp_scsi_queuecommand and
 247  *      zfcp_scsi_command_sync
 248  * @adapter: adapter for where scsi command is issued
 249  * @unit: unit to which scsi command is sent
 250  * @scpnt: scsi command to be sent
 251  *
 252  * Note: In scsi_done function must be set in scpnt.
 253  */
 254 int
 255 zfcp_scsi_command_async(struct zfcp_adapter *adapter, struct zfcp_unit *unit,
 256                         struct scsi_cmnd *scpnt)
 257 {
 258         int tmp;
 259         int retval;
 260
 261         retval = 0;
 262
 263         BUG_ON((adapter == NULL) || (adapter != unit->port->adapter));
 264         BUG_ON(scpnt->scsi_done == NULL);
 265
 266         if (unlikely(NULL == unit)) {
 267                 zfcp_scsi_command_fail(scpnt, DID_NO_CONNECT);
 268                 goto out;
 269         }
 270
 271         if (unlikely(
 272               atomic_test_mask(ZFCP_STATUS_COMMON_ERP_FAILED, &unit->status) ||
 273              !atomic_test_mask(ZFCP_STATUS_COMMON_RUNNING, &unit->status))) {
 274                 ZFCP_LOG_DEBUG("stopping SCSI I/O on unit 0x%016Lx on port "
 275                                "0x%016Lx on adapter %s\n",
 276                                unit->fcp_lun, unit->port->wwpn,
 277                                zfcp_get_busid_by_adapter(adapter));
 278                 zfcp_scsi_command_fail(scpnt, DID_ERROR);
 279                 goto out;
 280         }
 281
 282         if (unlikely(
 283              !atomic_test_mask(ZFCP_STATUS_COMMON_UNBLOCKED, &unit->status))) {
 284                 ZFCP_LOG_DEBUG("adapter %s not ready or unit 0x%016Lx "
 285                                "on port 0x%016Lx in recovery\n",
 286                                zfcp_get_busid_by_unit(unit),
 287                                unit->fcp_lun, unit->port->wwpn);
 288                 retval = SCSI_MLQUEUE_DEVICE_BUSY;
 289                 goto out;
 290         }
 291
 292         tmp = zfcp_fsf_send_fcp_command_task(adapter, unit, scpnt,
 293                                              ZFCP_REQ_AUTO_CLEANUP);
 294
 295         if (unlikely(tmp < 0)) {
 296                 ZFCP_LOG_DEBUG("error: initiation of Send FCP Cmnd failed\n");
 297                 retval = SCSI_MLQUEUE_HOST_BUSY;
 298         }
 299
 300 out:
 301         return retval;
 302 }
 303
 304 void
 305 zfcp_scsi_command_sync_handler(struct scsi_cmnd *scpnt)
 306 {
 307         struct completion *wait = (struct completion *) scpnt->SCp.ptr;
 308         complete(wait);
 309 }
 310
 311
 312 /**
 313  * zfcp_scsi_command_sync - send a SCSI command and wait for completion
 314  * returns 0, errors are indicated by scsi_cmnd->result
 315  */
 316 int
 317 zfcp_scsi_command_sync(struct zfcp_unit *unit, struct scsi_cmnd *scpnt)
 318 {
 319         DECLARE_COMPLETION(wait);
 320
 321         scpnt->SCp.ptr = (void *) &wait;  /* silent re-use */
 322         scpnt->done = zfcp_scsi_command_sync_handler;
 323         zfcp_scsi_command_async(unit->port->adapter, unit, scpnt);
 324         wait_for_completion(&wait);
 325
 326         return 0;
 327 }
 328
 329 /*
 330  * function:    zfcp_scsi_queuecommand
 331  *
 332  * purpose:     enqueues a SCSI command to the specified target device
 333  *
 334  * returns:     0 - success, SCSI command enqueued
 335  *              !0 - failure
 336  */
 337 int
 338 zfcp_scsi_queuecommand(struct scsi_cmnd *scpnt,
 339                        void (*done) (struct scsi_cmnd *))
 340 {
 341         struct zfcp_unit *unit;
 342         struct zfcp_adapter *adapter;
 343
 344         /* reset the status for this request */
 345         scpnt->result = 0;
 346         scpnt->host_scribble = NULL;
 347         scpnt->scsi_done = done;
 348
 349         /*
 350          * figure out adapter and target device
 351          * (stored there by zfcp_scsi_slave_alloc)
 352          */
 353         adapter = (struct zfcp_adapter *) scpnt->device->host->hostdata[0];
 354         unit = (struct zfcp_unit *) scpnt->device->hostdata;
 355
 356         return zfcp_scsi_command_async(adapter, unit, scpnt);
 357 }
 358
 359 /*
 360  * function:    zfcp_unit_lookup
 361  *
 362  * purpose:
 363  *
 364  * returns:
 365  *
 366  * context:
 367  */
 368 static struct zfcp_unit *
 369 zfcp_unit_lookup(struct zfcp_adapter *adapter, int channel, scsi_id_t id,
 370                  scsi_lun_t lun)
 371 {
 372         struct zfcp_port *port;
 373         struct zfcp_unit *unit, *retval = NULL;
 374
 375         list_for_each_entry(port, &adapter->port_list_head, list) {
 376                 if (id != port->scsi_id)
 377                         continue;
 378                 list_for_each_entry(unit, &port->unit_list_head, list) {
 379                         if (lun == unit->scsi_lun) {
 380                                 retval = unit;
 381                                 goto out;
 382                         }
 383                 }
 384         }
 385  out:
 386         return retval;
 387 }
 388
 389 /*
 390  * function:    zfcp_scsi_eh_abort_handler
 391  *
 392  * purpose:     tries to abort the specified (timed out) SCSI command
 393  *
 394  * note:        We do not need to care for a SCSI command which completes
 395  *              normally but late during this abort routine runs.
 396  *              We are allowed to return late commands to the SCSI stack.
 397  *              It tracks the state of commands and will handle late commands.
 398  *              (Usually, the normal completion of late commands is ignored with
 399  *              respect to the running abort operation. Grep for 'done_late'
 400  *              in the SCSI stacks sources.)
 401  *
 402  * returns:     SUCCESS - command has been aborted and cleaned up in internal
 403  *                        bookkeeping,
 404  *                        SCSI stack won't be called for aborted command
 405  *              FAILED  - otherwise
 406  */
 407 int
 408 zfcp_scsi_eh_abort_handler(struct scsi_cmnd *scpnt)
 409 {
 410         int retval = SUCCESS;
 411         struct zfcp_fsf_req *new_fsf_req, *old_fsf_req;
 412         struct zfcp_adapter *adapter = (struct zfcp_adapter *) scpnt->device->host->hostdata[0];
 413         struct zfcp_unit *unit = (struct zfcp_unit *) scpnt->device->hostdata;
 414         struct zfcp_port *port = unit->port;
 415         struct Scsi_Host *scsi_host = scpnt->device->host;
 416         union zfcp_req_data *req_data = NULL;
 417         unsigned long flags;
 418         u32 status = 0;
 419
 420         /* the components of a abort_dbf record (fixed size record) */
 421         u64 dbf_scsi_cmnd = (unsigned long) scpnt;
 422         char dbf_opcode[ZFCP_ABORT_DBF_LENGTH];
 423         wwn_t dbf_wwn = port->wwpn;
 424         fcp_lun_t dbf_fcp_lun = unit->fcp_lun;
 425         u64 dbf_retries = scpnt->retries;
 426         u64 dbf_allowed = scpnt->allowed;
 427         u64 dbf_timeout = 0;
 428         u64 dbf_fsf_req = 0;
 429         u64 dbf_fsf_status = 0;
 430         u64 dbf_fsf_qual[2] = { 0, 0 };
 431         char dbf_result[ZFCP_ABORT_DBF_LENGTH] = { "##undef" };
 432
 433         memset(dbf_opcode, 0, ZFCP_ABORT_DBF_LENGTH);
 434         memcpy(dbf_opcode,
 435                scpnt->cmnd,
 436                min(scpnt->cmd_len, (unsigned char) ZFCP_ABORT_DBF_LENGTH));
 437
 438         ZFCP_LOG_INFO("aborting scsi_cmnd=%p on adapter %s\n",
 439                       scpnt, zfcp_get_busid_by_adapter(adapter));
 440
 441         spin_unlock_irq(scsi_host->host_lock);
 442
 443         /*
 444          * Race condition between normal (late) completion and abort has
 445          * to be avoided.
 446          * The entirity of all accesses to scsi_req have to be atomic.
 447          * scsi_req is usually part of the fsf_req and thus we block the
 448          * release of fsf_req as long as we need to access scsi_req.
 449          */
 450         write_lock_irqsave(&adapter->abort_lock, flags);
 451
 452         /*
 453          * Check whether command has just completed and can not be aborted.
 454          * Even if the command has just been completed late, we can access
 455          * scpnt since the SCSI stack does not release it at least until
 456          * this routine returns. (scpnt is parameter passed to this routine
 457          * and must not disappear during abort even on late completion.)
 458          */
 459         req_data = (union zfcp_req_data *) scpnt->host_scribble;
 460         /* DEBUG */
 461         ZFCP_LOG_DEBUG("req_data=%p\n", req_data);
 462         if (!req_data) {
 463                 ZFCP_LOG_DEBUG("late command completion overtook abort\n");
 464                 /*
 465                  * That's it.
 466                  * Do not initiate abort but return SUCCESS.
 467                  */
 468                 write_unlock_irqrestore(&adapter->abort_lock, flags);
 469                 retval = SUCCESS;
 470                 strncpy(dbf_result, "##late1", ZFCP_ABORT_DBF_LENGTH);
 471                 goto out;
 472         }
 473
 474         /* Figure out which fsf_req needs to be aborted. */
 475         old_fsf_req = req_data->send_fcp_command_task.fsf_req;
 476
 477         dbf_fsf_req = (unsigned long) old_fsf_req;
 478         dbf_timeout =
 479             (jiffies - req_data->send_fcp_command_task.start_jiffies) / HZ;
 480
 481         ZFCP_LOG_DEBUG("old_fsf_req=%p\n", old_fsf_req);
 482         if (!old_fsf_req) {
 483                 write_unlock_irqrestore(&adapter->abort_lock, flags);
 484                 ZFCP_LOG_NORMAL("bug: no old fsf request found\n");
 485                 ZFCP_LOG_NORMAL("req_data:\n");
 486                 ZFCP_HEX_DUMP(ZFCP_LOG_LEVEL_NORMAL,
 487                               (char *) req_data, sizeof (union zfcp_req_data));
 488                 ZFCP_LOG_NORMAL("scsi_cmnd:\n");
 489                 ZFCP_HEX_DUMP(ZFCP_LOG_LEVEL_NORMAL,
 490                               (char *) scpnt, sizeof (struct scsi_cmnd));
 491                 retval = FAILED;
 492                 strncpy(dbf_result, "##bug:r", ZFCP_ABORT_DBF_LENGTH);
 493                 goto out;
 494         }
 495         old_fsf_req->data.send_fcp_command_task.scsi_cmnd = NULL;
 496         /* mark old request as being aborted */
 497         old_fsf_req->status |= ZFCP_STATUS_FSFREQ_ABORTING;
 498         /*
 499          * We have to collect all information (e.g. unit) needed by
 500          * zfcp_fsf_abort_fcp_command before calling that routine
 501          * since that routine is not allowed to access
 502          * fsf_req which it is going to abort.
 503          * This is because of we need to release fsf_req_list_lock
 504          * before calling zfcp_fsf_abort_fcp_command.
 505          * Since this lock will not be held, fsf_req may complete
 506          * late and may be released meanwhile.
 507          */
 508         ZFCP_LOG_DEBUG("unit 0x%016Lx (%p)\n", unit->fcp_lun, unit);
 509
 510         /*
 511          * The 'Abort FCP Command' routine may block (call schedule)
 512          * because it may wait for a free SBAL.
 513          * That's why we must release the lock and enable the
 514          * interrupts before.
 515          * On the other hand we do not need the lock anymore since
 516          * all critical accesses to scsi_req are done.
 517          */
 518         write_unlock_irqrestore(&adapter->abort_lock, flags);
 519         /* call FSF routine which does the abort */
 520         new_fsf_req = zfcp_fsf_abort_fcp_command((unsigned long) old_fsf_req,
 521                                                  adapter,
 522                                                  unit, ZFCP_WAIT_FOR_SBAL);
 523         ZFCP_LOG_DEBUG("new_fsf_req=%p\n", new_fsf_req);
 524         if (!new_fsf_req) {
 525                 retval = FAILED;
 526                 ZFCP_LOG_NORMAL("error: initiation of Abort FCP Cmnd "
 527                                 "failed\n");
 528                 strncpy(dbf_result, "##nores", ZFCP_ABORT_DBF_LENGTH);
 529                 goto out;
 530         }
 531
 532         /* wait for completion of abort */
 533         ZFCP_LOG_DEBUG("waiting for cleanup...\n");
 534 #if 1
 535         /*
 536          * FIXME:
 537          * copying zfcp_fsf_req_wait_and_cleanup code is not really nice
 538          */
 539         __wait_event(new_fsf_req->completion_wq,
 540                      new_fsf_req->status & ZFCP_STATUS_FSFREQ_COMPLETED);
 541         status = new_fsf_req->status;
 542         dbf_fsf_status = new_fsf_req->qtcb->header.fsf_status;
 543         /*
 544          * Ralphs special debug load provides timestamps in the FSF
 545          * status qualifier. This might be specified later if being
 546          * useful for debugging aborts.
 547          */
 548         dbf_fsf_qual[0] =
 549             *(u64 *) & new_fsf_req->qtcb->header.fsf_status_qual.word[0];
 550         dbf_fsf_qual[1] =
 551             *(u64 *) & new_fsf_req->qtcb->header.fsf_status_qual.word[2];
 552         zfcp_fsf_req_cleanup(new_fsf_req);
 553 #else
 554         retval = zfcp_fsf_req_wait_and_cleanup(new_fsf_req,
 555                                                ZFCP_UNINTERRUPTIBLE, &status);
 556 #endif
 557         ZFCP_LOG_DEBUG("Waiting for cleanup complete, status=0x%x\n", status);
 558         /* status should be valid since signals were not permitted */
 559         if (status & ZFCP_STATUS_FSFREQ_ABORTSUCCEEDED) {
 560                 retval = SUCCESS;
 561                 strncpy(dbf_result, "##succ", ZFCP_ABORT_DBF_LENGTH);
 562         } else if (status & ZFCP_STATUS_FSFREQ_ABORTNOTNEEDED) {
 563                 retval = SUCCESS;
 564                 strncpy(dbf_result, "##late2", ZFCP_ABORT_DBF_LENGTH);
 565         } else {
 566                 retval = FAILED;
 567                 strncpy(dbf_result, "##fail", ZFCP_ABORT_DBF_LENGTH);
 568         }
 569
 570  out:
 571         debug_event(adapter->abort_dbf, 1, &dbf_scsi_cmnd, sizeof (u64));
 572         debug_event(adapter->abort_dbf, 1, &dbf_opcode, ZFCP_ABORT_DBF_LENGTH);
 573         debug_event(adapter->abort_dbf, 1, &dbf_wwn, sizeof (wwn_t));
 574         debug_event(adapter->abort_dbf, 1, &dbf_fcp_lun, sizeof (fcp_lun_t));
 575         debug_event(adapter->abort_dbf, 1, &dbf_retries, sizeof (u64));
 576         debug_event(adapter->abort_dbf, 1, &dbf_allowed, sizeof (u64));
 577         debug_event(adapter->abort_dbf, 1, &dbf_timeout, sizeof (u64));
 578         debug_event(adapter->abort_dbf, 1, &dbf_fsf_req, sizeof (u64));
 579         debug_event(adapter->abort_dbf, 1, &dbf_fsf_status, sizeof (u64));
 580         debug_event(adapter->abort_dbf, 1, &dbf_fsf_qual[0], sizeof (u64));
 581         debug_event(adapter->abort_dbf, 1, &dbf_fsf_qual[1], sizeof (u64));
 582         debug_text_event(adapter->abort_dbf, 1, dbf_result);
 583
 584         spin_lock_irq(scsi_host->host_lock);
 585         return retval;
 586 }
 587
 588 /*
 589  * function:    zfcp_scsi_eh_device_reset_handler
 590  *
 591  * purpose:
 592  *
 593  * returns:
 594  */
 595 int
 596 zfcp_scsi_eh_device_reset_handler(struct scsi_cmnd *scpnt)
 597 {
 598         int retval;
 599         struct zfcp_unit *unit = (struct zfcp_unit *) scpnt->device->hostdata;
 600         struct Scsi_Host *scsi_host = scpnt->device->host;
 601
 602         spin_unlock_irq(scsi_host->host_lock);
 603
 604         if (!unit) {
 605                 ZFCP_LOG_NORMAL("bug: Tried reset for nonexistent unit\n");
 606                 retval = SUCCESS;
 607                 goto out;
 608         }
 609         ZFCP_LOG_NORMAL("resetting unit 0x%016Lx\n", unit->fcp_lun);
 610
 611         /*
 612          * If we do not know whether the unit supports 'logical unit reset'
 613          * then try 'logical unit reset' and proceed with 'target reset'
 614          * if 'logical unit reset' fails.
 615          * If the unit is known not to support 'logical unit reset' then
 616          * skip 'logical unit reset' and try 'target reset' immediately.
 617          */
 618         if (!atomic_test_mask(ZFCP_STATUS_UNIT_NOTSUPPUNITRESET,
 619                               &unit->status)) {
 620                 retval =
 621                     zfcp_task_management_function(unit, LOGICAL_UNIT_RESET);
 622                 if (retval) {
 623                         ZFCP_LOG_DEBUG("unit reset failed (unit=%p)\n", unit);
 624                         if (retval == -ENOTSUPP)
 625                                 atomic_set_mask
 626                                     (ZFCP_STATUS_UNIT_NOTSUPPUNITRESET,
 627                                      &unit->status);
 628                         /* fall through and try 'target reset' next */
 629                 } else {
 630                         ZFCP_LOG_DEBUG("unit reset succeeded (unit=%p)\n",
 631                                        unit);
 632                         /* avoid 'target reset' */
 633                         retval = SUCCESS;
 634                         goto out;
 635                 }
 636         }
 637         retval = zfcp_task_management_function(unit, TARGET_RESET);
 638         if (retval) {
 639                 ZFCP_LOG_DEBUG("target reset failed (unit=%p)\n", unit);
 640                 retval = FAILED;
 641         } else {
 642                 ZFCP_LOG_DEBUG("target reset succeeded (unit=%p)\n", unit);
 643                 retval = SUCCESS;
 644         }
 645  out:
 646         spin_lock_irq(scsi_host->host_lock);
 647         return retval;
 648 }
 649
 650 static int
 651 zfcp_task_management_function(struct zfcp_unit *unit, u8 tm_flags)
 652 {
 653         struct zfcp_adapter *adapter = unit->port->adapter;
 654         int retval;
 655         int status;
 656         struct zfcp_fsf_req *fsf_req;
 657
 658         /* issue task management function */
 659         fsf_req = zfcp_fsf_send_fcp_command_task_management
 660             (adapter, unit, tm_flags, ZFCP_WAIT_FOR_SBAL);
 661         if (!fsf_req) {
 662                 ZFCP_LOG_INFO("error: creation of task management request "
 663                               "failed for unit 0x%016Lx on port 0x%016Lx on  "
 664                               "adapter %s\n", unit->fcp_lun, unit->port->wwpn,
 665                               zfcp_get_busid_by_adapter(adapter));
 666                 retval = -ENOMEM;
 667                 goto out;
 668         }
 669
 670         retval = zfcp_fsf_req_wait_and_cleanup(fsf_req,
 671                                                ZFCP_UNINTERRUPTIBLE, &status);
 672         /*
 673          * check completion status of task management function
 674          * (status should always be valid since no signals permitted)
 675          */
 676         if (status & ZFCP_STATUS_FSFREQ_TMFUNCFAILED)
 677                 retval = -EIO;
 678         else if (status & ZFCP_STATUS_FSFREQ_TMFUNCNOTSUPP)
 679                 retval = -ENOTSUPP;
 680         else
 681                 retval = 0;
 682  out:
 683         return retval;
 684 }
 685
 686 /*
 687  * function:    zfcp_scsi_eh_bus_reset_handler
 688  *
 689  * purpose:
 690  *
 691  * returns:
 692  */
 693 int
 694 zfcp_scsi_eh_bus_reset_handler(struct scsi_cmnd *scpnt)
 695 {
 696         int retval = 0;
 697         struct zfcp_unit *unit;
 698         struct Scsi_Host *scsi_host = scpnt->device->host;
 699
 700         spin_unlock_irq(scsi_host->host_lock);
 701
 702         unit = (struct zfcp_unit *) scpnt->device->hostdata;
 703         ZFCP_LOG_NORMAL("bus reset because of problems with "
 704                         "unit 0x%016Lx\n", unit->fcp_lun);
 705         zfcp_erp_adapter_reopen(unit->port->adapter, 0);
 706         zfcp_erp_wait(unit->port->adapter);
 707         retval = SUCCESS;
 708
 709         spin_lock_irq(scsi_host->host_lock);
 710         return retval;
 711 }
 712
 713 /*
 714  * function:    zfcp_scsi_eh_host_reset_handler
 715  *
 716  * purpose:
 717  *
 718  * returns:
 719  */
 720 int
 721 zfcp_scsi_eh_host_reset_handler(struct scsi_cmnd *scpnt)
 722 {
 723         int retval = 0;
 724         struct zfcp_unit *unit;
 725         struct Scsi_Host *scsi_host = scpnt->device->host;
 726
 727         spin_unlock_irq(scsi_host->host_lock);
 728
 729         unit = (struct zfcp_unit *) scpnt->device->hostdata;
 730         ZFCP_LOG_NORMAL("host reset because of problems with "
 731                         "unit 0x%016Lx\n", unit->fcp_lun);
 732         zfcp_erp_adapter_reopen(unit->port->adapter, 0);
 733         zfcp_erp_wait(unit->port->adapter);
 734         retval = SUCCESS;
 735
 736         spin_lock_irq(scsi_host->host_lock);
 737         return retval;
 738 }
 739
 740 /*
 741  * function:
 742  *
 743  * purpose:
 744  *
 745  * returns:
 746  */
 747 int
 748 zfcp_adapter_scsi_register(struct zfcp_adapter *adapter)
 749 {
 750         int retval = 0;
 751         static unsigned int unique_id = 0;
 752
 753         /* register adapter as SCSI host with mid layer of SCSI stack */
 754         adapter->scsi_host = scsi_host_alloc(&zfcp_data.scsi_host_template,
 755                                              sizeof (struct zfcp_adapter *));
 756         if (!adapter->scsi_host) {
 757                 ZFCP_LOG_NORMAL("error: registration with SCSI stack failed "
 758                                 "for adapter %s ",
 759                                 zfcp_get_busid_by_adapter(adapter));
 760                 retval = -EIO;
 761                 goto out;
 762         }
 763         ZFCP_LOG_DEBUG("host registered, scsi_host=%p\n", adapter->scsi_host);
 764
 765         /* tell the SCSI stack some characteristics of this adapter */
 766         adapter->scsi_host->max_id = 1;
 767         adapter->scsi_host->max_lun = 1;
 768         adapter->scsi_host->max_channel = 0;
 769         adapter->scsi_host->unique_id = unique_id++;    /* FIXME */
 770         adapter->scsi_host->max_cmd_len = ZFCP_MAX_SCSI_CMND_LENGTH;
 771         /*
 772          * Reverse mapping of the host number to avoid race condition
 773          */
 774         adapter->scsi_host_no = adapter->scsi_host->host_no;
 775
 776         /*
 777          * save a pointer to our own adapter data structure within
 778          * hostdata field of SCSI host data structure
 779          */
 780         adapter->scsi_host->hostdata[0] = (unsigned long) adapter;
 781
 782         if (scsi_add_host(adapter->scsi_host, &adapter->ccw_device->dev)) {
 783                 scsi_host_put(adapter->scsi_host);
 784                 retval = -EIO;
 785                 goto out;
 786         }
 787         atomic_set_mask(ZFCP_STATUS_ADAPTER_REGISTERED, &adapter->status);
 788  out:
 789         return retval;
 790 }
 791
 792 /*
 793  * function:
 794  *
 795  * purpose:
 796  *
 797  * returns:
 798  */
 799 void
 800 zfcp_adapter_scsi_unregister(struct zfcp_adapter *adapter)
 801 {
 802         struct Scsi_Host *shost;
 803
 804         shost = adapter->scsi_host;
 805         if (!shost)
 806                 return;
 807         scsi_remove_host(shost);
 808         scsi_host_put(shost);
 809         adapter->scsi_host = NULL;
 810         adapter->scsi_host_no = 0;
 811         atomic_clear_mask(ZFCP_STATUS_ADAPTER_REGISTERED, &adapter->status);
 812
 813         return;
 814 }
 815
 816
 817 void
 818 zfcp_fsf_start_scsi_er_timer(struct zfcp_adapter *adapter)
 819 {
 820         adapter->scsi_er_timer.function = zfcp_fsf_scsi_er_timeout_handler;
 821         adapter->scsi_er_timer.data = (unsigned long) adapter;
 822         adapter->scsi_er_timer.expires = jiffies + ZFCP_SCSI_ER_TIMEOUT;
 823         add_timer(&adapter->scsi_er_timer);
 824 }
 825
 826
 827 /**
 828  * ZFCP_DEFINE_SCSI_ATTR
 829  * @_name:   name of show attribute
 830  * @_format: format string
 831  * @_value:  value to print
 832  *
 833  * Generates attribute for a unit.
 834  */
 835 #define ZFCP_DEFINE_SCSI_ATTR(_name, _format, _value)                    \
 836 static ssize_t zfcp_sysfs_scsi_##_name##_show(struct device *dev,        \
 837                                               char *buf)                 \
 838 {                                                                        \
 839         struct scsi_device *sdev;                                        \
 840         struct zfcp_unit *unit;                                          \
 841                                                                          \
 842         sdev = to_scsi_device(dev);                                      \
 843         unit = sdev->hostdata;                                           \
 844         return sprintf(buf, _format, _value);                            \
 845 }                                                                        \
 846                                                                          \
 847 static DEVICE_ATTR(_name, S_IRUGO, zfcp_sysfs_scsi_##_name##_show, NULL);
 848
 849 ZFCP_DEFINE_SCSI_ATTR(hba_id, "%s\n", zfcp_get_busid_by_unit(unit));
 850 ZFCP_DEFINE_SCSI_ATTR(wwpn, "0x%016llx\n", unit->port->wwpn);
 851 ZFCP_DEFINE_SCSI_ATTR(fcp_lun, "0x%016llx\n", unit->fcp_lun);
 852
 853 static struct device_attribute *zfcp_sysfs_sdev_attrs[] = {
 854         &dev_attr_fcp_lun,
 855         &dev_attr_wwpn,
 856         &dev_attr_hba_id,
 857         NULL
 858 };
 859
 860 #undef ZFCP_LOG_AREA