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   1 /*
   2  * File...........: linux/drivers/s390/block/dasd_fba.c
   3  * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
   4  * Bugreports.to..: <Linux390@de.ibm.com>
   5  * Copyright IBM Corp. 1999, 2009
   6  */
   7
   8 #define KMSG_COMPONENT "dasd-fba"
   9
  10 #include <linux/stddef.h>
  11 #include <linux/kernel.h>
  12 #include <asm/debug.h>
  13
  14 #include <linux/slab.h>
  15 #include <linux/hdreg.h>        /* HDIO_GETGEO                      */
  16 #include <linux/bio.h>
  17 #include <linux/module.h>
  18 #include <linux/init.h>
  19
  20 #include <asm/idals.h>
  21 #include <asm/ebcdic.h>
  22 #include <asm/io.h>
  23 #include <asm/ccwdev.h>
  24
  25 #include "dasd_int.h"
  26 #include "dasd_fba.h"
  27
  28 #ifdef PRINTK_HEADER
  29 #undef PRINTK_HEADER
  30 #endif                          /* PRINTK_HEADER */
  31 #define PRINTK_HEADER "dasd(fba):"
  32
  33 #define DASD_FBA_CCW_WRITE 0x41
  34 #define DASD_FBA_CCW_READ 0x42
  35 #define DASD_FBA_CCW_LOCATE 0x43
  36 #define DASD_FBA_CCW_DEFINE_EXTENT 0x63
  37
  38 MODULE_LICENSE("GPL");
  39
  40 static struct dasd_discipline dasd_fba_discipline;
  41
  42 struct dasd_fba_private {
  43         struct dasd_fba_characteristics rdc_data;
  44 };
  45
  46 static struct ccw_device_id dasd_fba_ids[] = {
  47         { CCW_DEVICE_DEVTYPE (0x6310, 0, 0x9336, 0), .driver_info = 0x1},
  48         { CCW_DEVICE_DEVTYPE (0x3880, 0, 0x3370, 0), .driver_info = 0x2},
  49         { /* end of list */ },
  50 };
  51
  52 MODULE_DEVICE_TABLE(ccw, dasd_fba_ids);
  53
  54 static struct ccw_driver dasd_fba_driver; /* see below */
  55 static int
  56 dasd_fba_probe(struct ccw_device *cdev)
  57 {
  58         return dasd_generic_probe(cdev, &dasd_fba_discipline);
  59 }
  60
  61 static int
  62 dasd_fba_set_online(struct ccw_device *cdev)
  63 {
  64         return dasd_generic_set_online(cdev, &dasd_fba_discipline);
  65 }
  66
  67 static struct ccw_driver dasd_fba_driver = {
  68         .name        = "dasd-fba",
  69         .owner       = THIS_MODULE,
  70         .ids         = dasd_fba_ids,
  71         .probe       = dasd_fba_probe,
  72         .remove      = dasd_generic_remove,
  73         .set_offline = dasd_generic_set_offline,
  74         .set_online  = dasd_fba_set_online,
  75         .notify      = dasd_generic_notify,
  76         .freeze      = dasd_generic_pm_freeze,
  77         .thaw        = dasd_generic_restore_device,
  78         .restore     = dasd_generic_restore_device,
  79 };
  80
  81 static void
  82 define_extent(struct ccw1 * ccw, struct DE_fba_data *data, int rw,
  83               int blksize, int beg, int nr)
  84 {
  85         ccw->cmd_code = DASD_FBA_CCW_DEFINE_EXTENT;
  86         ccw->flags = 0;
  87         ccw->count = 16;
  88         ccw->cda = (__u32) __pa(data);
  89         memset(data, 0, sizeof (struct DE_fba_data));
  90         if (rw == WRITE)
  91                 (data->mask).perm = 0x0;
  92         else if (rw == READ)
  93                 (data->mask).perm = 0x1;
  94         else
  95                 data->mask.perm = 0x2;
  96         data->blk_size = blksize;
  97         data->ext_loc = beg;
  98         data->ext_end = nr - 1;
  99 }
 100
 101 static void
 102 locate_record(struct ccw1 * ccw, struct LO_fba_data *data, int rw,
 103               int block_nr, int block_ct)
 104 {
 105         ccw->cmd_code = DASD_FBA_CCW_LOCATE;
 106         ccw->flags = 0;
 107         ccw->count = 8;
 108         ccw->cda = (__u32) __pa(data);
 109         memset(data, 0, sizeof (struct LO_fba_data));
 110         if (rw == WRITE)
 111                 data->operation.cmd = 0x5;
 112         else if (rw == READ)
 113                 data->operation.cmd = 0x6;
 114         else
 115                 data->operation.cmd = 0x8;
 116         data->blk_nr = block_nr;
 117         data->blk_ct = block_ct;
 118 }
 119
 120 static int
 121 dasd_fba_check_characteristics(struct dasd_device *device)
 122 {
 123         struct dasd_block *block;
 124         struct dasd_fba_private *private;
 125         struct ccw_device *cdev = device->cdev;
 126         int rc;
 127
 128         private = (struct dasd_fba_private *) device->private;
 129         if (!private) {
 130                 private = kzalloc(sizeof(*private), GFP_KERNEL | GFP_DMA);
 131                 if (!private) {
 132                         dev_warn(&device->cdev->dev,
 133                                  "Allocating memory for private DASD "
 134                                  "data failed\n");
 135                         return -ENOMEM;
 136                 }
 137                 device->private = (void *) private;
 138         } else {
 139                 memset(private, 0, sizeof(*private));
 140         }
 141         block = dasd_alloc_block();
 142         if (IS_ERR(block)) {
 143                 DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s", "could not allocate "
 144                                 "dasd block structure");
 145                 device->private = NULL;
 146                 kfree(private);
 147                 return PTR_ERR(block);
 148         }
 149         device->block = block;
 150         block->base = device;
 151
 152         /* Read Device Characteristics */
 153         rc = dasd_generic_read_dev_chars(device, DASD_FBA_MAGIC,
 154                                          &private->rdc_data, 32);
 155         if (rc) {
 156                 DBF_EVENT_DEVID(DBF_WARNING, cdev, "Read device "
 157                                 "characteristics returned error %d", rc);
 158                 device->block = NULL;
 159                 dasd_free_block(block);
 160                 device->private = NULL;
 161                 kfree(private);
 162                 return rc;
 163         }
 164
 165         dev_info(&device->cdev->dev,
 166                  "New FBA DASD %04X/%02X (CU %04X/%02X) with %d MB "
 167                  "and %d B/blk\n",
 168                  cdev->id.dev_type,
 169                  cdev->id.dev_model,
 170                  cdev->id.cu_type,
 171                  cdev->id.cu_model,
 172                  ((private->rdc_data.blk_bdsa *
 173                    (private->rdc_data.blk_size >> 9)) >> 11),
 174                  private->rdc_data.blk_size);
 175         return 0;
 176 }
 177
 178 static int dasd_fba_do_analysis(struct dasd_block *block)
 179 {
 180         struct dasd_fba_private *private;
 181         int sb, rc;
 182
 183         private = (struct dasd_fba_private *) block->base->private;
 184         rc = dasd_check_blocksize(private->rdc_data.blk_size);
 185         if (rc) {
 186                 DBF_DEV_EVENT(DBF_WARNING, block->base, "unknown blocksize %d",
 187                             private->rdc_data.blk_size);
 188                 return rc;
 189         }
 190         block->blocks = private->rdc_data.blk_bdsa;
 191         block->bp_block = private->rdc_data.blk_size;
 192         block->s2b_shift = 0;   /* bits to shift 512 to get a block */
 193         for (sb = 512; sb < private->rdc_data.blk_size; sb = sb << 1)
 194                 block->s2b_shift++;
 195         return 0;
 196 }
 197
 198 static int dasd_fba_fill_geometry(struct dasd_block *block,
 199                                   struct hd_geometry *geo)
 200 {
 201         if (dasd_check_blocksize(block->bp_block) != 0)
 202                 return -EINVAL;
 203         geo->cylinders = (block->blocks << block->s2b_shift) >> 10;
 204         geo->heads = 16;
 205         geo->sectors = 128 >> block->s2b_shift;
 206         return 0;
 207 }
 208
 209 static dasd_erp_fn_t
 210 dasd_fba_erp_action(struct dasd_ccw_req * cqr)
 211 {
 212         return dasd_default_erp_action;
 213 }
 214
 215 static dasd_erp_fn_t
 216 dasd_fba_erp_postaction(struct dasd_ccw_req * cqr)
 217 {
 218         if (cqr->function == dasd_default_erp_action)
 219                 return dasd_default_erp_postaction;
 220
 221         DBF_DEV_EVENT(DBF_WARNING, cqr->startdev, "unknown ERP action %p",
 222                     cqr->function);
 223         return NULL;
 224 }
 225
 226 static void dasd_fba_handle_unsolicited_interrupt(struct dasd_device *device,
 227                                                    struct irb *irb)
 228 {
 229         char mask;
 230
 231         /* first of all check for state change pending interrupt */
 232         mask = DEV_STAT_ATTENTION | DEV_STAT_DEV_END | DEV_STAT_UNIT_EXCEP;
 233         if ((irb->scsw.cmd.dstat & mask) == mask) {
 234                 dasd_generic_handle_state_change(device);
 235                 return;
 236         }
 237
 238         /* check for unsolicited interrupts */
 239         DBF_DEV_EVENT(DBF_WARNING, device, "%s",
 240                     "unsolicited interrupt received");
 241         device->discipline->dump_sense_dbf(device, irb, "unsolicited");
 242         dasd_schedule_device_bh(device);
 243         return;
 244 };
 245
 246 static struct dasd_ccw_req *dasd_fba_build_cp(struct dasd_device * memdev,
 247                                               struct dasd_block *block,
 248                                               struct request *req)
 249 {
 250         struct dasd_fba_private *private;
 251         unsigned long *idaws;
 252         struct LO_fba_data *LO_data;
 253         struct dasd_ccw_req *cqr;
 254         struct ccw1 *ccw;
 255         struct req_iterator iter;
 256         struct bio_vec *bv;
 257         char *dst;
 258         int count, cidaw, cplength, datasize;
 259         sector_t recid, first_rec, last_rec;
 260         unsigned int blksize, off;
 261         unsigned char cmd;
 262
 263         private = (struct dasd_fba_private *) block->base->private;
 264         if (rq_data_dir(req) == READ) {
 265                 cmd = DASD_FBA_CCW_READ;
 266         } else if (rq_data_dir(req) == WRITE) {
 267                 cmd = DASD_FBA_CCW_WRITE;
 268         } else
 269                 return ERR_PTR(-EINVAL);
 270         blksize = block->bp_block;
 271         /* Calculate record id of first and last block. */
 272         first_rec = blk_rq_pos(req) >> block->s2b_shift;
 273         last_rec =
 274                 (blk_rq_pos(req) + blk_rq_sectors(req) - 1) >> block->s2b_shift;
 275         /* Check struct bio and count the number of blocks for the request. */
 276         count = 0;
 277         cidaw = 0;
 278         rq_for_each_segment(bv, req, iter) {
 279                 if (bv->bv_len & (blksize - 1))
 280                         /* Fba can only do full blocks. */
 281                         return ERR_PTR(-EINVAL);
 282                 count += bv->bv_len >> (block->s2b_shift + 9);
 283 #if defined(CONFIG_64BIT)
 284                 if (idal_is_needed (page_address(bv->bv_page), bv->bv_len))
 285                         cidaw += bv->bv_len / blksize;
 286 #endif
 287         }
 288         /* Paranoia. */
 289         if (count != last_rec - first_rec + 1)
 290                 return ERR_PTR(-EINVAL);
 291         /* 1x define extent + 1x locate record + number of blocks */
 292         cplength = 2 + count;
 293         /* 1x define extent + 1x locate record */
 294         datasize = sizeof(struct DE_fba_data) + sizeof(struct LO_fba_data) +
 295                 cidaw * sizeof(unsigned long);
 296         /*
 297          * Find out number of additional locate record ccws if the device
 298          * can't do data chaining.
 299          */
 300         if (private->rdc_data.mode.bits.data_chain == 0) {
 301                 cplength += count - 1;
 302                 datasize += (count - 1)*sizeof(struct LO_fba_data);
 303         }
 304         /* Allocate the ccw request. */
 305         cqr = dasd_smalloc_request(DASD_FBA_MAGIC, cplength, datasize, memdev);
 306         if (IS_ERR(cqr))
 307                 return cqr;
 308         ccw = cqr->cpaddr;
 309         /* First ccw is define extent. */
 310         define_extent(ccw++, cqr->data, rq_data_dir(req),
 311                       block->bp_block, blk_rq_pos(req), blk_rq_sectors(req));
 312         /* Build locate_record + read/write ccws. */
 313         idaws = (unsigned long *) (cqr->data + sizeof(struct DE_fba_data));
 314         LO_data = (struct LO_fba_data *) (idaws + cidaw);
 315         /* Locate record for all blocks for smart devices. */
 316         if (private->rdc_data.mode.bits.data_chain != 0) {
 317                 ccw[-1].flags |= CCW_FLAG_CC;
 318                 locate_record(ccw++, LO_data++, rq_data_dir(req), 0, count);
 319         }
 320         recid = first_rec;
 321         rq_for_each_segment(bv, req, iter) {
 322                 dst = page_address(bv->bv_page) + bv->bv_offset;
 323                 if (dasd_page_cache) {
 324                         char *copy = kmem_cache_alloc(dasd_page_cache,
 325                                                       GFP_DMA | __GFP_NOWARN);
 326                         if (copy && rq_data_dir(req) == WRITE)
 327                                 memcpy(copy + bv->bv_offset, dst, bv->bv_len);
 328                         if (copy)
 329                                 dst = copy + bv->bv_offset;
 330                 }
 331                 for (off = 0; off < bv->bv_len; off += blksize) {
 332                         /* Locate record for stupid devices. */
 333                         if (private->rdc_data.mode.bits.data_chain == 0) {
 334                                 ccw[-1].flags |= CCW_FLAG_CC;
 335                                 locate_record(ccw, LO_data++,
 336                                               rq_data_dir(req),
 337                                               recid - first_rec, 1);
 338                                 ccw->flags = CCW_FLAG_CC;
 339                                 ccw++;
 340                         } else {
 341                                 if (recid > first_rec)
 342                                         ccw[-1].flags |= CCW_FLAG_DC;
 343                                 else
 344                                         ccw[-1].flags |= CCW_FLAG_CC;
 345                         }
 346                         ccw->cmd_code = cmd;
 347                         ccw->count = block->bp_block;
 348                         if (idal_is_needed(dst, blksize)) {
 349                                 ccw->cda = (__u32)(addr_t) idaws;
 350                                 ccw->flags = CCW_FLAG_IDA;
 351                                 idaws = idal_create_words(idaws, dst, blksize);
 352                         } else {
 353                                 ccw->cda = (__u32)(addr_t) dst;
 354                                 ccw->flags = 0;
 355                         }
 356                         ccw++;
 357                         dst += blksize;
 358                         recid++;
 359                 }
 360         }
 361         if (blk_noretry_request(req) ||
 362             block->base->features & DASD_FEATURE_FAILFAST)
 363                 set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
 364         cqr->startdev = memdev;
 365         cqr->memdev = memdev;
 366         cqr->block = block;
 367         cqr->expires = 5 * 60 * HZ;     /* 5 minutes */
 368         cqr->retries = 32;
 369         cqr->buildclk = get_clock();
 370         cqr->status = DASD_CQR_FILLED;
 371         return cqr;
 372 }
 373
 374 static int
 375 dasd_fba_free_cp(struct dasd_ccw_req *cqr, struct request *req)
 376 {
 377         struct dasd_fba_private *private;
 378         struct ccw1 *ccw;
 379         struct req_iterator iter;
 380         struct bio_vec *bv;
 381         char *dst, *cda;
 382         unsigned int blksize, off;
 383         int status;
 384
 385         if (!dasd_page_cache)
 386                 goto out;
 387         private = (struct dasd_fba_private *) cqr->block->base->private;
 388         blksize = cqr->block->bp_block;
 389         ccw = cqr->cpaddr;
 390         /* Skip over define extent & locate record. */
 391         ccw++;
 392         if (private->rdc_data.mode.bits.data_chain != 0)
 393                 ccw++;
 394         rq_for_each_segment(bv, req, iter) {
 395                 dst = page_address(bv->bv_page) + bv->bv_offset;
 396                 for (off = 0; off < bv->bv_len; off += blksize) {
 397                         /* Skip locate record. */
 398                         if (private->rdc_data.mode.bits.data_chain == 0)
 399                                 ccw++;
 400                         if (dst) {
 401                                 if (ccw->flags & CCW_FLAG_IDA)
 402                                         cda = *((char **)((addr_t) ccw->cda));
 403                                 else
 404                                         cda = (char *)((addr_t) ccw->cda);
 405                                 if (dst != cda) {
 406                                         if (rq_data_dir(req) == READ)
 407                                                 memcpy(dst, cda, bv->bv_len);
 408                                         kmem_cache_free(dasd_page_cache,
 409                                             (void *)((addr_t)cda & PAGE_MASK));
 410                                 }
 411                                 dst = NULL;
 412                         }
 413                         ccw++;
 414                 }
 415         }
 416 out:
 417         status = cqr->status == DASD_CQR_DONE;
 418         dasd_sfree_request(cqr, cqr->memdev);
 419         return status;
 420 }
 421
 422 static void dasd_fba_handle_terminated_request(struct dasd_ccw_req *cqr)
 423 {
 424         cqr->status = DASD_CQR_FILLED;
 425 };
 426
 427 static int
 428 dasd_fba_fill_info(struct dasd_device * device,
 429                    struct dasd_information2_t * info)
 430 {
 431         info->label_block = 1;
 432         info->FBA_layout = 1;
 433         info->format = DASD_FORMAT_LDL;
 434         info->characteristics_size = sizeof(struct dasd_fba_characteristics);
 435         memcpy(info->characteristics,
 436                &((struct dasd_fba_private *) device->private)->rdc_data,
 437                sizeof (struct dasd_fba_characteristics));
 438         info->confdata_size = 0;
 439         return 0;
 440 }
 441
 442 static void
 443 dasd_fba_dump_sense_dbf(struct dasd_device *device, struct irb *irb,
 444                         char *reason)
 445 {
 446         u64 *sense;
 447
 448         sense = (u64 *) dasd_get_sense(irb);
 449         if (sense) {
 450                 DBF_DEV_EVENT(DBF_EMERG, device,
 451                               "%s: %s %02x%02x%02x %016llx %016llx %016llx "
 452                               "%016llx", reason,
 453                               scsw_is_tm(&irb->scsw) ? "t" : "c",
 454                               scsw_cc(&irb->scsw), scsw_cstat(&irb->scsw),
 455                               scsw_dstat(&irb->scsw), sense[0], sense[1],
 456                               sense[2], sense[3]);
 457         } else {
 458                 DBF_DEV_EVENT(DBF_EMERG, device, "%s",
 459                               "SORRY - NO VALID SENSE AVAILABLE\n");
 460         }
 461 }
 462
 463
 464 static void
 465 dasd_fba_dump_sense(struct dasd_device *device, struct dasd_ccw_req * req,
 466                     struct irb *irb)
 467 {
 468         char *page;
 469         struct ccw1 *act, *end, *last;
 470         int len, sl, sct, count;
 471
 472         page = (char *) get_zeroed_page(GFP_ATOMIC);
 473         if (page == NULL) {
 474                 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
 475                             "No memory to dump sense data");
 476                 return;
 477         }
 478         len = sprintf(page, KERN_ERR PRINTK_HEADER
 479                       " I/O status report for device %s:\n",
 480                       dev_name(&device->cdev->dev));
 481         len += sprintf(page + len, KERN_ERR PRINTK_HEADER
 482                        " in req: %p CS: 0x%02X DS: 0x%02X\n", req,
 483                        irb->scsw.cmd.cstat, irb->scsw.cmd.dstat);
 484         len += sprintf(page + len, KERN_ERR PRINTK_HEADER
 485                        " device %s: Failing CCW: %p\n",
 486                        dev_name(&device->cdev->dev),
 487                        (void *) (addr_t) irb->scsw.cmd.cpa);
 488         if (irb->esw.esw0.erw.cons) {
 489                 for (sl = 0; sl < 4; sl++) {
 490                         len += sprintf(page + len, KERN_ERR PRINTK_HEADER
 491                                        " Sense(hex) %2d-%2d:",
 492                                        (8 * sl), ((8 * sl) + 7));
 493
 494                         for (sct = 0; sct < 8; sct++) {
 495                                 len += sprintf(page + len, " %02x",
 496                                                irb->ecw[8 * sl + sct]);
 497                         }
 498                         len += sprintf(page + len, "\n");
 499                 }
 500         } else {
 501                 len += sprintf(page + len, KERN_ERR PRINTK_HEADER
 502                                " SORRY - NO VALID SENSE AVAILABLE\n");
 503         }
 504         printk(KERN_ERR "%s", page);
 505
 506         /* dump the Channel Program */
 507         /* print first CCWs (maximum 8) */
 508         act = req->cpaddr;
 509         for (last = act; last->flags & (CCW_FLAG_CC | CCW_FLAG_DC); last++);
 510         end = min(act + 8, last);
 511         len = sprintf(page, KERN_ERR PRINTK_HEADER
 512                       " Related CP in req: %p\n", req);
 513         while (act <= end) {
 514                 len += sprintf(page + len, KERN_ERR PRINTK_HEADER
 515                                " CCW %p: %08X %08X DAT:",
 516                                act, ((int *) act)[0], ((int *) act)[1]);
 517                 for (count = 0; count < 32 && count < act->count;
 518                      count += sizeof(int))
 519                         len += sprintf(page + len, " %08X",
 520                                        ((int *) (addr_t) act->cda)
 521                                        [(count>>2)]);
 522                 len += sprintf(page + len, "\n");
 523                 act++;
 524         }
 525         printk(KERN_ERR "%s", page);
 526
 527
 528         /* print failing CCW area */
 529         len = 0;
 530         if (act <  ((struct ccw1 *)(addr_t) irb->scsw.cmd.cpa) - 2) {
 531                 act = ((struct ccw1 *)(addr_t) irb->scsw.cmd.cpa) - 2;
 532                 len += sprintf(page + len, KERN_ERR PRINTK_HEADER "......\n");
 533         }
 534         end = min((struct ccw1 *)(addr_t) irb->scsw.cmd.cpa + 2, last);
 535         while (act <= end) {
 536                 len += sprintf(page + len, KERN_ERR PRINTK_HEADER
 537                                " CCW %p: %08X %08X DAT:",
 538                                act, ((int *) act)[0], ((int *) act)[1]);
 539                 for (count = 0; count < 32 && count < act->count;
 540                      count += sizeof(int))
 541                         len += sprintf(page + len, " %08X",
 542                                        ((int *) (addr_t) act->cda)
 543                                        [(count>>2)]);
 544                 len += sprintf(page + len, "\n");
 545                 act++;
 546         }
 547
 548         /* print last CCWs */
 549         if (act <  last - 2) {
 550                 act = last - 2;
 551                 len += sprintf(page + len, KERN_ERR PRINTK_HEADER "......\n");
 552         }
 553         while (act <= last) {
 554                 len += sprintf(page + len, KERN_ERR PRINTK_HEADER
 555                                " CCW %p: %08X %08X DAT:",
 556                                act, ((int *) act)[0], ((int *) act)[1]);
 557                 for (count = 0; count < 32 && count < act->count;
 558                      count += sizeof(int))
 559                         len += sprintf(page + len, " %08X",
 560                                        ((int *) (addr_t) act->cda)
 561                                        [(count>>2)]);
 562                 len += sprintf(page + len, "\n");
 563                 act++;
 564         }
 565         if (len > 0)
 566                 printk(KERN_ERR "%s", page);
 567         free_page((unsigned long) page);
 568 }
 569
 570 /*
 571  * max_blocks is dependent on the amount of storage that is available
 572  * in the static io buffer for each device. Currently each device has
 573  * 8192 bytes (=2 pages). For 64 bit one dasd_mchunkt_t structure has
 574  * 24 bytes, the struct dasd_ccw_req has 136 bytes and each block can use
 575  * up to 16 bytes (8 for the ccw and 8 for the idal pointer). In
 576  * addition we have one define extent ccw + 16 bytes of data and a
 577  * locate record ccw for each block (stupid devices!) + 16 bytes of data.
 578  * That makes:
 579  * (8192 - 24 - 136 - 8 - 16) / 40 = 200.2 blocks at maximum.
 580  * We want to fit two into the available memory so that we can immediately
 581  * start the next request if one finishes off. That makes 100.1 blocks
 582  * for one request. Give a little safety and the result is 96.
 583  */
 584 static struct dasd_discipline dasd_fba_discipline = {
 585         .owner = THIS_MODULE,
 586         .name = "FBA ",
 587         .ebcname = "FBA ",
 588         .max_blocks = 96,
 589         .check_device = dasd_fba_check_characteristics,
 590         .do_analysis = dasd_fba_do_analysis,
 591         .fill_geometry = dasd_fba_fill_geometry,
 592         .start_IO = dasd_start_IO,
 593         .term_IO = dasd_term_IO,
 594         .handle_terminated_request = dasd_fba_handle_terminated_request,
 595         .erp_action = dasd_fba_erp_action,
 596         .erp_postaction = dasd_fba_erp_postaction,
 597         .handle_unsolicited_interrupt = dasd_fba_handle_unsolicited_interrupt,
 598         .build_cp = dasd_fba_build_cp,
 599         .free_cp = dasd_fba_free_cp,
 600         .dump_sense = dasd_fba_dump_sense,
 601         .dump_sense_dbf = dasd_fba_dump_sense_dbf,
 602         .fill_info = dasd_fba_fill_info,
 603 };
 604
 605 static int __init
 606 dasd_fba_init(void)
 607 {
 608         int ret;
 609
 610         ASCEBC(dasd_fba_discipline.ebcname, 4);
 611         ret = ccw_driver_register(&dasd_fba_driver);
 612         if (!ret)
 613                 wait_for_device_probe();
 614
 615         return ret;
 616 }
 617
 618 static void __exit
 619 dasd_fba_cleanup(void)
 620 {
 621         ccw_driver_unregister(&dasd_fba_driver);
 622 }
 623
 624 module_init(dasd_fba_init);
 625 module_exit(dasd_fba_cleanup);