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: 1.61 $"
  35
  36 #include <linux/blkdev.h>
  37
  38 #include "zfcp_ext.h"
  39
  40 static void zfcp_scsi_slave_destroy(struct scsi_device *sdp);
  41 static int zfcp_scsi_slave_alloc(struct scsi_device *sdp);
  42 static int zfcp_scsi_slave_configure(struct scsi_device *sdp);
  43 static int zfcp_scsi_queuecommand(struct scsi_cmnd *,
  44                                   void (*done) (struct scsi_cmnd *));
  45 static int zfcp_scsi_eh_abort_handler(struct scsi_cmnd *);
  46 static int zfcp_scsi_eh_device_reset_handler(struct scsi_cmnd *);
  47 static int zfcp_scsi_eh_bus_reset_handler(struct scsi_cmnd *);
  48 static int zfcp_scsi_eh_host_reset_handler(struct scsi_cmnd *);
  49 static int zfcp_task_management_function(struct zfcp_unit *, u8);
  50
  51 static struct zfcp_unit *zfcp_unit_lookup(struct zfcp_adapter *, int, scsi_id_t,
  52                                           scsi_lun_t);
  53
  54 static struct device_attribute *zfcp_sysfs_sdev_attrs[];
  55
  56 struct zfcp_data zfcp_data = {
  57         .scsi_host_template = {
  58               name:                    ZFCP_NAME,
  59               proc_name:               "zfcp",
  60               proc_info:               NULL,
  61               detect:                  NULL,
  62               slave_alloc:             zfcp_scsi_slave_alloc,
  63               slave_configure:         zfcp_scsi_slave_configure,
  64               slave_destroy:           zfcp_scsi_slave_destroy,
  65               queuecommand:            zfcp_scsi_queuecommand,
  66               eh_abort_handler:        zfcp_scsi_eh_abort_handler,
  67               eh_device_reset_handler: zfcp_scsi_eh_device_reset_handler,
  68               eh_bus_reset_handler:    zfcp_scsi_eh_bus_reset_handler,
  69               eh_host_reset_handler:   zfcp_scsi_eh_host_reset_handler,
  70                                        /* FIXME(openfcp): Tune */
  71               can_queue:               4096,
  72               this_id:                 0,
  73               /*
  74                * FIXME:
  75                * one less? can zfcp_create_sbale cope with it?
  76                */
  77               sg_tablesize:            ZFCP_MAX_SBALES_PER_REQ,
  78               cmd_per_lun:             1,
  79               unchecked_isa_dma:       0,
  80               use_clustering:          1,
  81               sdev_attrs:              zfcp_sysfs_sdev_attrs,
  82         }
  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 = -ENODEV;
 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         zfcp_cmd_dbf_event_scsi("failing", scpnt);
 243         /* return directly */
 244         scpnt->scsi_done(scpnt);
 245 }
 246
 247 /**
 248  * zfcp_scsi_command_async - worker for zfcp_scsi_queuecommand and
 249  *      zfcp_scsi_command_sync
 250  * @adapter: adapter for where scsi command is issued
 251  * @unit: unit to which scsi command is sent
 252  * @scpnt: scsi command to be sent
 253  *
 254  * Note: In scsi_done function must be set in scpnt.
 255  */
 256 int
 257 zfcp_scsi_command_async(struct zfcp_adapter *adapter, struct zfcp_unit *unit,
 258                         struct scsi_cmnd *scpnt)
 259 {
 260         int tmp;
 261         int retval;
 262
 263         retval = 0;
 264
 265         BUG_ON((adapter == NULL) || (adapter != unit->port->adapter));
 266         BUG_ON(scpnt->scsi_done == NULL);
 267
 268         if (unlikely(NULL == unit)) {
 269                 zfcp_scsi_command_fail(scpnt, DID_NO_CONNECT);
 270                 goto out;
 271         }
 272
 273         if (unlikely(
 274               atomic_test_mask(ZFCP_STATUS_COMMON_ERP_FAILED, &unit->status) ||
 275              !atomic_test_mask(ZFCP_STATUS_COMMON_RUNNING, &unit->status))) {
 276                 ZFCP_LOG_DEBUG("stopping SCSI I/O on unit 0x%016Lx on port "
 277                                "0x%016Lx on adapter %s\n",
 278                                unit->fcp_lun, unit->port->wwpn,
 279                                zfcp_get_busid_by_adapter(adapter));
 280                 zfcp_scsi_command_fail(scpnt, DID_ERROR);
 281                 goto out;
 282         }
 283
 284         if (unlikely(
 285              !atomic_test_mask(ZFCP_STATUS_COMMON_UNBLOCKED, &unit->status))) {
 286                 ZFCP_LOG_DEBUG("adapter %s not ready or unit 0x%016Lx "
 287                                "on port 0x%016Lx in recovery\n",
 288                                zfcp_get_busid_by_unit(unit),
 289                                unit->fcp_lun, unit->port->wwpn);
 290                 retval = SCSI_MLQUEUE_DEVICE_BUSY;
 291                 goto out;
 292         }
 293
 294         tmp = zfcp_fsf_send_fcp_command_task(adapter, unit, scpnt,
 295                                              ZFCP_REQ_AUTO_CLEANUP);
 296
 297         if (unlikely(tmp < 0)) {
 298                 ZFCP_LOG_DEBUG("error: initiation of Send FCP Cmnd failed\n");
 299                 retval = SCSI_MLQUEUE_HOST_BUSY;
 300         }
 301
 302 out:
 303         return retval;
 304 }
 305
 306 void
 307 zfcp_scsi_command_sync_handler(struct scsi_cmnd *scpnt)
 308 {
 309         struct completion *wait = (struct completion *) scpnt->SCp.ptr;
 310         complete(wait);
 311 }
 312
 313
 314 /**
 315  * zfcp_scsi_command_sync - send a SCSI command and wait for completion
 316  * returns 0, errors are indicated by scsi_cmnd->result
 317  */
 318 int
 319 zfcp_scsi_command_sync(struct zfcp_unit *unit, struct scsi_cmnd *scpnt)
 320 {
 321         DECLARE_COMPLETION(wait);
 322
 323         scpnt->SCp.ptr = (void *) &wait;  /* silent re-use */
 324         scpnt->done = zfcp_scsi_command_sync_handler;
 325         zfcp_scsi_command_async(unit->port->adapter, unit, scpnt);
 326         wait_for_completion(&wait);
 327
 328         return 0;
 329 }
 330
 331 /*
 332  * function:    zfcp_scsi_queuecommand
 333  *
 334  * purpose:     enqueues a SCSI command to the specified target device
 335  *
 336  * returns:     0 - success, SCSI command enqueued
 337  *              !0 - failure
 338  */
 339 int
 340 zfcp_scsi_queuecommand(struct scsi_cmnd *scpnt,
 341                        void (*done) (struct scsi_cmnd *))
 342 {
 343         struct zfcp_unit *unit;
 344         struct zfcp_adapter *adapter;
 345
 346         /* reset the status for this request */
 347         scpnt->result = 0;
 348         scpnt->host_scribble = NULL;
 349         scpnt->scsi_done = done;
 350
 351         /*
 352          * figure out adapter and target device
 353          * (stored there by zfcp_scsi_slave_alloc)
 354          */
 355         adapter = (struct zfcp_adapter *) scpnt->device->host->hostdata[0];
 356         unit = (struct zfcp_unit *) scpnt->device->hostdata;
 357
 358         return zfcp_scsi_command_async(adapter, unit, scpnt);
 359 }
 360
 361 /*
 362  * function:    zfcp_unit_lookup
 363  *
 364  * purpose:
 365  *
 366  * returns:
 367  *
 368  * context:
 369  */
 370 static struct zfcp_unit *
 371 zfcp_unit_lookup(struct zfcp_adapter *adapter, int channel, scsi_id_t id,
 372                  scsi_lun_t lun)
 373 {
 374         struct zfcp_port *port;
 375         struct zfcp_unit *unit, *retval = NULL;
 376
 377         list_for_each_entry(port, &adapter->port_list_head, list) {
 378                 if (id != port->scsi_id)
 379                         continue;
 380                 list_for_each_entry(unit, &port->unit_list_head, list) {
 381                         if (lun == unit->scsi_lun) {
 382                                 retval = unit;
 383                                 goto out;
 384                         }
 385                 }
 386         }
 387  out:
 388         return retval;
 389 }
 390
 391 /*
 392  * function:    zfcp_scsi_eh_abort_handler
 393  *
 394  * purpose:     tries to abort the specified (timed out) SCSI command
 395  *
 396  * note:        We do not need to care for a SCSI command which completes
 397  *              normally but late during this abort routine runs.
 398  *              We are allowed to return late commands to the SCSI stack.
 399  *              It tracks the state of commands and will handle late commands.
 400  *              (Usually, the normal completion of late commands is ignored with
 401  *              respect to the running abort operation. Grep for 'done_late'
 402  *              in the SCSI stacks sources.)
 403  *
 404  * returns:     SUCCESS - command has been aborted and cleaned up in internal
 405  *                        bookkeeping,
 406  *                        SCSI stack won't be called for aborted command
 407  *              FAILED  - otherwise
 408  */
 409 int
 410 zfcp_scsi_eh_abort_handler(struct scsi_cmnd *scpnt)
 411 {
 412         int retval = SUCCESS;
 413         struct zfcp_fsf_req *new_fsf_req, *old_fsf_req;
 414         struct zfcp_adapter *adapter = (struct zfcp_adapter *) scpnt->device->host->hostdata[0];
 415         struct zfcp_unit *unit = (struct zfcp_unit *) scpnt->device->hostdata;
 416         struct zfcp_port *port = unit->port;
 417         struct Scsi_Host *scsi_host = scpnt->device->host;
 418         union zfcp_req_data *req_data = NULL;
 419         unsigned long flags;
 420         u32 status = 0;
 421
 422         /* the components of a abort_dbf record (fixed size record) */
 423         u64 dbf_scsi_cmnd = (unsigned long) scpnt;
 424         char dbf_opcode[ZFCP_ABORT_DBF_LENGTH];
 425         wwn_t dbf_wwn = port->wwpn;
 426         fcp_lun_t dbf_fcp_lun = unit->fcp_lun;
 427         u64 dbf_retries = scpnt->retries;
 428         u64 dbf_allowed = scpnt->allowed;
 429         u64 dbf_timeout = 0;
 430         u64 dbf_fsf_req = 0;
 431         u64 dbf_fsf_status = 0;
 432         u64 dbf_fsf_qual[2] = { 0, 0 };
 433         char dbf_result[ZFCP_ABORT_DBF_LENGTH] = { "##undef" };
 434
 435         memset(dbf_opcode, 0, ZFCP_ABORT_DBF_LENGTH);
 436         memcpy(dbf_opcode,
 437                scpnt->cmnd,
 438                min(scpnt->cmd_len, (unsigned char) ZFCP_ABORT_DBF_LENGTH));
 439
 440         ZFCP_LOG_INFO("aborting scsi_cmnd=%p on adapter %s\n",
 441                       scpnt, zfcp_get_busid_by_adapter(adapter));
 442
 443         spin_unlock_irq(scsi_host->host_lock);
 444
 445         /*
 446          * Race condition between normal (late) completion and abort has
 447          * to be avoided.
 448          * The entirity of all accesses to scsi_req have to be atomic.
 449          * scsi_req is usually part of the fsf_req and thus we block the
 450          * release of fsf_req as long as we need to access scsi_req.
 451          */
 452         write_lock_irqsave(&adapter->abort_lock, flags);
 453
 454         /*
 455          * Check whether command has just completed and can not be aborted.
 456          * Even if the command has just been completed late, we can access
 457          * scpnt since the SCSI stack does not release it at least until
 458          * this routine returns. (scpnt is parameter passed to this routine
 459          * and must not disappear during abort even on late completion.)
 460          */
 461         req_data = (union zfcp_req_data *) scpnt->host_scribble;
 462         /* DEBUG */
 463         ZFCP_LOG_DEBUG("req_data=%p\n", req_data);
 464         if (!req_data) {
 465                 ZFCP_LOG_DEBUG("late command completion overtook abort\n");
 466                 /*
 467                  * That's it.
 468                  * Do not initiate abort but return SUCCESS.
 469                  */
 470                 write_unlock_irqrestore(&adapter->abort_lock, flags);
 471                 retval = SUCCESS;
 472                 strncpy(dbf_result, "##late1", ZFCP_ABORT_DBF_LENGTH);
 473                 goto out;
 474         }
 475
 476         /* Figure out which fsf_req needs to be aborted. */
 477         old_fsf_req = req_data->send_fcp_command_task.fsf_req;
 478
 479         dbf_fsf_req = (unsigned long) old_fsf_req;
 480         dbf_timeout =
 481             (jiffies - req_data->send_fcp_command_task.start_jiffies) / HZ;
 482
 483         ZFCP_LOG_DEBUG("old_fsf_req=%p\n", old_fsf_req);
 484         if (!old_fsf_req) {
 485                 write_unlock_irqrestore(&adapter->abort_lock, flags);
 486                 ZFCP_LOG_NORMAL("bug: no old fsf request found\n");
 487                 ZFCP_LOG_NORMAL("req_data:\n");
 488                 ZFCP_HEX_DUMP(ZFCP_LOG_LEVEL_NORMAL,
 489                               (char *) req_data, sizeof (union zfcp_req_data));
 490                 ZFCP_LOG_NORMAL("scsi_cmnd:\n");
 491                 ZFCP_HEX_DUMP(ZFCP_LOG_LEVEL_NORMAL,
 492                               (char *) scpnt, sizeof (struct scsi_cmnd));
 493                 retval = FAILED;
 494                 strncpy(dbf_result, "##bug:r", ZFCP_ABORT_DBF_LENGTH);
 495                 goto out;
 496         }
 497         old_fsf_req->data.send_fcp_command_task.scsi_cmnd = NULL;
 498         /* mark old request as being aborted */
 499         old_fsf_req->status |= ZFCP_STATUS_FSFREQ_ABORTING;
 500         /*
 501          * We have to collect all information (e.g. unit) needed by
 502          * zfcp_fsf_abort_fcp_command before calling that routine
 503          * since that routine is not allowed to access
 504          * fsf_req which it is going to abort.
 505          * This is because of we need to release fsf_req_list_lock
 506          * before calling zfcp_fsf_abort_fcp_command.
 507          * Since this lock will not be held, fsf_req may complete
 508          * late and may be released meanwhile.
 509          */
 510         ZFCP_LOG_DEBUG("unit 0x%016Lx (%p)\n", unit->fcp_lun, unit);
 511
 512         /*
 513          * The 'Abort FCP Command' routine may block (call schedule)
 514          * because it may wait for a free SBAL.
 515          * That's why we must release the lock and enable the
 516          * interrupts before.
 517          * On the other hand we do not need the lock anymore since
 518          * all critical accesses to scsi_req are done.
 519          */
 520         write_unlock_irqrestore(&adapter->abort_lock, flags);
 521         /* call FSF routine which does the abort */
 522         new_fsf_req = zfcp_fsf_abort_fcp_command((unsigned long) old_fsf_req,
 523                                                  adapter,
 524                                                  unit, ZFCP_WAIT_FOR_SBAL);
 525         ZFCP_LOG_DEBUG("new_fsf_req=%p\n", new_fsf_req);
 526         if (!new_fsf_req) {
 527                 retval = FAILED;
 528                 ZFCP_LOG_NORMAL("error: initiation of Abort FCP Cmnd "
 529                                 "failed\n");
 530                 strncpy(dbf_result, "##nores", ZFCP_ABORT_DBF_LENGTH);
 531                 goto out;
 532         }
 533
 534         /* wait for completion of abort */
 535         ZFCP_LOG_DEBUG("waiting for cleanup...\n");
 536 #if 1
 537         /*
 538          * FIXME:
 539          * copying zfcp_fsf_req_wait_and_cleanup code is not really nice
 540          */
 541         __wait_event(new_fsf_req->completion_wq,
 542                      new_fsf_req->status & ZFCP_STATUS_FSFREQ_COMPLETED);
 543         status = new_fsf_req->status;
 544         dbf_fsf_status = new_fsf_req->qtcb->header.fsf_status;
 545         /*
 546          * Ralphs special debug load provides timestamps in the FSF
 547          * status qualifier. This might be specified later if being
 548          * useful for debugging aborts.
 549          */
 550         dbf_fsf_qual[0] =
 551             *(u64 *) & new_fsf_req->qtcb->header.fsf_status_qual.word[0];
 552         dbf_fsf_qual[1] =
 553             *(u64 *) & new_fsf_req->qtcb->header.fsf_status_qual.word[2];
 554         zfcp_fsf_req_cleanup(new_fsf_req);
 555 #else
 556         retval = zfcp_fsf_req_wait_and_cleanup(new_fsf_req,
 557                                                ZFCP_UNINTERRUPTIBLE, &status);
 558 #endif
 559         ZFCP_LOG_DEBUG("Waiting for cleanup complete, status=0x%x\n", status);
 560         /* status should be valid since signals were not permitted */
 561         if (status & ZFCP_STATUS_FSFREQ_ABORTSUCCEEDED) {
 562                 retval = SUCCESS;
 563                 strncpy(dbf_result, "##succ", ZFCP_ABORT_DBF_LENGTH);
 564         } else if (status & ZFCP_STATUS_FSFREQ_ABORTNOTNEEDED) {
 565                 retval = SUCCESS;
 566                 strncpy(dbf_result, "##late2", ZFCP_ABORT_DBF_LENGTH);
 567         } else {
 568                 retval = FAILED;
 569                 strncpy(dbf_result, "##fail", ZFCP_ABORT_DBF_LENGTH);
 570         }
 571
 572  out:
 573         debug_event(adapter->abort_dbf, 1, &dbf_scsi_cmnd, sizeof (u64));
 574         debug_event(adapter->abort_dbf, 1, &dbf_opcode, ZFCP_ABORT_DBF_LENGTH);
 575         debug_event(adapter->abort_dbf, 1, &dbf_wwn, sizeof (wwn_t));
 576         debug_event(adapter->abort_dbf, 1, &dbf_fcp_lun, sizeof (fcp_lun_t));
 577         debug_event(adapter->abort_dbf, 1, &dbf_retries, sizeof (u64));
 578         debug_event(adapter->abort_dbf, 1, &dbf_allowed, sizeof (u64));
 579         debug_event(adapter->abort_dbf, 1, &dbf_timeout, sizeof (u64));
 580         debug_event(adapter->abort_dbf, 1, &dbf_fsf_req, sizeof (u64));
 581         debug_event(adapter->abort_dbf, 1, &dbf_fsf_status, sizeof (u64));
 582         debug_event(adapter->abort_dbf, 1, &dbf_fsf_qual[0], sizeof (u64));
 583         debug_event(adapter->abort_dbf, 1, &dbf_fsf_qual[1], sizeof (u64));
 584         debug_text_event(adapter->abort_dbf, 1, dbf_result);
 585
 586         spin_lock_irq(scsi_host->host_lock);
 587         return retval;
 588 }
 589
 590 /*
 591  * function:    zfcp_scsi_eh_device_reset_handler
 592  *
 593  * purpose:
 594  *
 595  * returns:
 596  */
 597 int
 598 zfcp_scsi_eh_device_reset_handler(struct scsi_cmnd *scpnt)
 599 {
 600         int retval;
 601         struct zfcp_unit *unit = (struct zfcp_unit *) scpnt->device->hostdata;
 602         struct Scsi_Host *scsi_host = scpnt->device->host;
 603
 604         spin_unlock_irq(scsi_host->host_lock);
 605
 606         if (!unit) {
 607                 ZFCP_LOG_NORMAL("bug: Tried reset for nonexistent unit\n");
 608                 retval = SUCCESS;
 609                 goto out;
 610         }
 611         ZFCP_LOG_NORMAL("resetting unit 0x%016Lx\n", unit->fcp_lun);
 612
 613         /*
 614          * If we do not know whether the unit supports 'logical unit reset'
 615          * then try 'logical unit reset' and proceed with 'target reset'
 616          * if 'logical unit reset' fails.
 617          * If the unit is known not to support 'logical unit reset' then
 618          * skip 'logical unit reset' and try 'target reset' immediately.
 619          */
 620         if (!atomic_test_mask(ZFCP_STATUS_UNIT_NOTSUPPUNITRESET,
 621                               &unit->status)) {
 622                 retval =
 623                     zfcp_task_management_function(unit, LOGICAL_UNIT_RESET);
 624                 if (retval) {
 625                         ZFCP_LOG_DEBUG("unit reset failed (unit=%p)\n", unit);
 626                         if (retval == -ENOTSUPP)
 627                                 atomic_set_mask
 628                                     (ZFCP_STATUS_UNIT_NOTSUPPUNITRESET,
 629                                      &unit->status);
 630                         /* fall through and try 'target reset' next */
 631                 } else {
 632                         ZFCP_LOG_DEBUG("unit reset succeeded (unit=%p)\n",
 633                                        unit);
 634                         /* avoid 'target reset' */
 635                         retval = SUCCESS;
 636                         goto out;
 637                 }
 638         }
 639         retval = zfcp_task_management_function(unit, TARGET_RESET);
 640         if (retval) {
 641                 ZFCP_LOG_DEBUG("target reset failed (unit=%p)\n", unit);
 642                 retval = FAILED;
 643         } else {
 644                 ZFCP_LOG_DEBUG("target reset succeeded (unit=%p)\n", unit);
 645                 retval = SUCCESS;
 646         }
 647  out:
 648         spin_lock_irq(scsi_host->host_lock);
 649         return retval;
 650 }
 651
 652 static int
 653 zfcp_task_management_function(struct zfcp_unit *unit, u8 tm_flags)
 654 {
 655         struct zfcp_adapter *adapter = unit->port->adapter;
 656         int retval;
 657         int status;
 658         struct zfcp_fsf_req *fsf_req;
 659
 660         /* issue task management function */
 661         fsf_req = zfcp_fsf_send_fcp_command_task_management
 662             (adapter, unit, tm_flags, ZFCP_WAIT_FOR_SBAL);
 663         if (!fsf_req) {
 664                 ZFCP_LOG_INFO("error: creation of task management request "
 665                               "failed for unit 0x%016Lx on port 0x%016Lx on  "
 666                               "adapter %s\n", unit->fcp_lun, unit->port->wwpn,
 667                               zfcp_get_busid_by_adapter(adapter));
 668                 retval = -ENOMEM;
 669                 goto out;
 670         }
 671
 672         retval = zfcp_fsf_req_wait_and_cleanup(fsf_req,
 673                                                ZFCP_UNINTERRUPTIBLE, &status);
 674         /*
 675          * check completion status of task management function
 676          * (status should always be valid since no signals permitted)
 677          */
 678         if (status & ZFCP_STATUS_FSFREQ_TMFUNCFAILED)
 679                 retval = -EIO;
 680         else if (status & ZFCP_STATUS_FSFREQ_TMFUNCNOTSUPP)
 681                 retval = -ENOTSUPP;
 682         else
 683                 retval = 0;
 684  out:
 685         return retval;
 686 }
 687
 688 /*
 689  * function:    zfcp_scsi_eh_bus_reset_handler
 690  *
 691  * purpose:
 692  *
 693  * returns:
 694  */
 695 int
 696 zfcp_scsi_eh_bus_reset_handler(struct scsi_cmnd *scpnt)
 697 {
 698         int retval = 0;
 699         struct zfcp_unit *unit;
 700         struct Scsi_Host *scsi_host = scpnt->device->host;
 701
 702         spin_unlock_irq(scsi_host->host_lock);
 703
 704         unit = (struct zfcp_unit *) scpnt->device->hostdata;
 705         ZFCP_LOG_NORMAL("bus reset because of problems with "
 706                         "unit 0x%016Lx\n", unit->fcp_lun);
 707         zfcp_erp_adapter_reopen(unit->port->adapter, 0);
 708         zfcp_erp_wait(unit->port->adapter);
 709         retval = SUCCESS;
 710
 711         spin_lock_irq(scsi_host->host_lock);
 712         return retval;
 713 }
 714
 715 /*
 716  * function:    zfcp_scsi_eh_host_reset_handler
 717  *
 718  * purpose:
 719  *
 720  * returns:
 721  */
 722 int
 723 zfcp_scsi_eh_host_reset_handler(struct scsi_cmnd *scpnt)
 724 {
 725         int retval = 0;
 726         struct zfcp_unit *unit;
 727         struct Scsi_Host *scsi_host = scpnt->device->host;
 728
 729         spin_unlock_irq(scsi_host->host_lock);
 730
 731         unit = (struct zfcp_unit *) scpnt->device->hostdata;
 732         ZFCP_LOG_NORMAL("host reset because of problems with "
 733                         "unit 0x%016Lx\n", unit->fcp_lun);
 734         zfcp_erp_adapter_reopen(unit->port->adapter, 0);
 735         zfcp_erp_wait(unit->port->adapter);
 736         retval = SUCCESS;
 737
 738         spin_lock_irq(scsi_host->host_lock);
 739         return retval;
 740 }
 741
 742 /*
 743  * function:
 744  *
 745  * purpose:
 746  *
 747  * returns:
 748  */
 749 int
 750 zfcp_adapter_scsi_register(struct zfcp_adapter *adapter)
 751 {
 752         int retval = 0;
 753         static unsigned int unique_id = 0;
 754
 755         /* register adapter as SCSI host with mid layer of SCSI stack */
 756         adapter->scsi_host = scsi_host_alloc(&zfcp_data.scsi_host_template,
 757                                              sizeof (struct zfcp_adapter *));
 758         if (!adapter->scsi_host) {
 759                 ZFCP_LOG_NORMAL("error: registration with SCSI stack failed "
 760                                 "for adapter %s ",
 761                                 zfcp_get_busid_by_adapter(adapter));
 762                 retval = -EIO;
 763                 goto out;
 764         }
 765         ZFCP_LOG_DEBUG("host registered, scsi_host=%p\n", adapter->scsi_host);
 766
 767         /* tell the SCSI stack some characteristics of this adapter */
 768         adapter->scsi_host->max_id = 1;
 769         adapter->scsi_host->max_lun = 1;
 770         adapter->scsi_host->max_channel = 0;
 771         adapter->scsi_host->unique_id = unique_id++;    /* FIXME */
 772         adapter->scsi_host->max_cmd_len = ZFCP_MAX_SCSI_CMND_LENGTH;
 773         /*
 774          * Reverse mapping of the host number to avoid race condition
 775          */
 776         adapter->scsi_host_no = adapter->scsi_host->host_no;
 777
 778         /*
 779          * save a pointer to our own adapter data structure within
 780          * hostdata field of SCSI host data structure
 781          */
 782         adapter->scsi_host->hostdata[0] = (unsigned long) adapter;
 783
 784         if (scsi_add_host(adapter->scsi_host, &adapter->ccw_device->dev)) {
 785                 scsi_host_put(adapter->scsi_host);
 786                 retval = -EIO;
 787                 goto out;
 788         }
 789         atomic_set_mask(ZFCP_STATUS_ADAPTER_REGISTERED, &adapter->status);
 790  out:
 791         return retval;
 792 }
 793
 794 /*
 795  * function:
 796  *
 797  * purpose:
 798  *
 799  * returns:
 800  */
 801 void
 802 zfcp_adapter_scsi_unregister(struct zfcp_adapter *adapter)
 803 {
 804         struct Scsi_Host *shost;
 805
 806         shost = adapter->scsi_host;
 807         if (!shost)
 808                 return;
 809         scsi_remove_host(shost);
 810         scsi_host_put(shost);
 811         adapter->scsi_host = NULL;
 812         adapter->scsi_host_no = 0;
 813         atomic_clear_mask(ZFCP_STATUS_ADAPTER_REGISTERED, &adapter->status);
 814
 815         return;
 816 }
 817
 818
 819 void
 820 zfcp_fsf_start_scsi_er_timer(struct zfcp_adapter *adapter)
 821 {
 822         adapter->scsi_er_timer.function = zfcp_fsf_scsi_er_timeout_handler;
 823         adapter->scsi_er_timer.data = (unsigned long) adapter;
 824         adapter->scsi_er_timer.expires = jiffies + ZFCP_SCSI_ER_TIMEOUT;
 825         add_timer(&adapter->scsi_er_timer);
 826 }
 827
 828
 829 /**
 830  * ZFCP_DEFINE_SCSI_ATTR
 831  * @_name:   name of show attribute
 832  * @_format: format string
 833  * @_value:  value to print
 834  *
 835  * Generates attribute for a unit.
 836  */
 837 #define ZFCP_DEFINE_SCSI_ATTR(_name, _format, _value)                    \
 838 static ssize_t zfcp_sysfs_scsi_##_name##_show(struct device *dev,        \
 839                                               char *buf)                 \
 840 {                                                                        \
 841         struct scsi_device *sdev;                                        \
 842         struct zfcp_unit *unit;                                          \
 843                                                                          \
 844         sdev = to_scsi_device(dev);                                      \
 845         unit = sdev->hostdata;                                           \
 846         return sprintf(buf, _format, _value);                            \
 847 }                                                                        \
 848                                                                          \
 849 static DEVICE_ATTR(_name, S_IRUGO, zfcp_sysfs_scsi_##_name##_show, NULL);
 850
 851 ZFCP_DEFINE_SCSI_ATTR(hba_id, "%s\n", zfcp_get_busid_by_unit(unit));
 852 ZFCP_DEFINE_SCSI_ATTR(wwpn, "0x%016llx\n", unit->port->wwpn);
 853 ZFCP_DEFINE_SCSI_ATTR(fcp_lun, "0x%016llx\n", unit->fcp_lun);
 854
 855 static struct device_attribute *zfcp_sysfs_sdev_attrs[] = {
 856         &dev_attr_fcp_lun,
 857         &dev_attr_wwpn,
 858         &dev_attr_hba_id,
 859         NULL
 860 };
 861
 862 #undef ZFCP_LOG_AREA