drivers/s390/block/dasd_fba.c

   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         int readonly;
 128
 129         private = (struct dasd_fba_private *) device->private;
 130         if (!private) {
 131                 private = kzalloc(sizeof(*private), GFP_KERNEL | GFP_DMA);
 132                 if (!private) {
 133                         dev_warn(&device->cdev->dev,
 134                                  "Allocating memory for private DASD "
 135                                  "data failed\n");
 136                         return -ENOMEM;
 137                 }
 138                 device->private = (void *) private;
 139         } else {
 140                 memset(private, 0, sizeof(*private));
 141         }
 142         block = dasd_alloc_block();
 143         if (IS_ERR(block)) {
 144                 DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s", "could not allocate "
 145                                 "dasd block structure");
 146                 device->private = NULL;
 147                 kfree(private);
 148                 return PTR_ERR(block);
 149         }
 150         device->block = block;
 151         block->base = device;
 152
 153         /* Read Device Characteristics */
 154         rc = dasd_generic_read_dev_chars(device, DASD_FBA_MAGIC,
 155                                          &private->rdc_data, 32);
 156         if (rc) {
 157                 DBF_EVENT_DEVID(DBF_WARNING, cdev, "Read device "
 158                                 "characteristics returned error %d", rc);
 159                 device->block = NULL;
 160                 dasd_free_block(block);
 161                 device->private = NULL;
 162                 kfree(private);
 163                 return rc;
 164         }
 165
 166         device->default_expires = DASD_EXPIRES;
 167
 168         readonly = dasd_device_is_ro(device);
 169         if (readonly)
 170                 set_bit(DASD_FLAG_DEVICE_RO, &device->flags);
 171
 172         dev_info(&device->cdev->dev,
 173                  "New FBA DASD %04X/%02X (CU %04X/%02X) with %d MB "
 174                  "and %d B/blk%s\n",
 175                  cdev->id.dev_type,
 176                  cdev->id.dev_model,
 177                  cdev->id.cu_type,
 178                  cdev->id.cu_model,
 179                  ((private->rdc_data.blk_bdsa *
 180                    (private->rdc_data.blk_size >> 9)) >> 11),
 181                  private->rdc_data.blk_size,
 182                  readonly ? ", read-only device" : "");
 183         return 0;
 184 }
 185
 186 static int dasd_fba_do_analysis(struct dasd_block *block)
 187 {
 188         struct dasd_fba_private *private;
 189         int sb, rc;
 190
 191         private = (struct dasd_fba_private *) block->base->private;
 192         rc = dasd_check_blocksize(private->rdc_data.blk_size);
 193         if (rc) {
 194                 DBF_DEV_EVENT(DBF_WARNING, block->base, "unknown blocksize %d",
 195                             private->rdc_data.blk_size);
 196                 return rc;
 197         }
 198         block->blocks = private->rdc_data.blk_bdsa;
 199         block->bp_block = private->rdc_data.blk_size;
 200         block->s2b_shift = 0;   /* bits to shift 512 to get a block */
 201         for (sb = 512; sb < private->rdc_data.blk_size; sb = sb << 1)
 202                 block->s2b_shift++;
 203         return 0;
 204 }
 205
 206 static int dasd_fba_fill_geometry(struct dasd_block *block,
 207                                   struct hd_geometry *geo)
 208 {
 209         if (dasd_check_blocksize(block->bp_block) != 0)
 210                 return -EINVAL;
 211         geo->cylinders = (block->blocks << block->s2b_shift) >> 10;
 212         geo->heads = 16;
 213         geo->sectors = 128 >> block->s2b_shift;
 214         return 0;
 215 }
 216
 217 static dasd_erp_fn_t
 218 dasd_fba_erp_action(struct dasd_ccw_req * cqr)
 219 {
 220         return dasd_default_erp_action;
 221 }
 222
 223 static dasd_erp_fn_t
 224 dasd_fba_erp_postaction(struct dasd_ccw_req * cqr)
 225 {
 226         if (cqr->function == dasd_default_erp_action)
 227                 return dasd_default_erp_postaction;
 228
 229         DBF_DEV_EVENT(DBF_WARNING, cqr->startdev, "unknown ERP action %p",
 230                     cqr->function);
 231         return NULL;
 232 }
 233
 234 static void dasd_fba_handle_unsolicited_interrupt(struct dasd_device *device,
 235                                                    struct irb *irb)
 236 {
 237         char mask;
 238
 239         /* first of all check for state change pending interrupt */
 240         mask = DEV_STAT_ATTENTION | DEV_STAT_DEV_END | DEV_STAT_UNIT_EXCEP;
 241         if ((irb->scsw.cmd.dstat & mask) == mask) {
 242                 dasd_generic_handle_state_change(device);
 243                 return;
 244         }
 245
 246         /* check for unsolicited interrupts */
 247         DBF_DEV_EVENT(DBF_WARNING, device, "%s",
 248                     "unsolicited interrupt received");
 249         device->discipline->dump_sense_dbf(device, irb, "unsolicited");
 250         dasd_schedule_device_bh(device);
 251         return;
 252 };
 253
 254 static struct dasd_ccw_req *dasd_fba_build_cp(struct dasd_device * memdev,
 255                                               struct dasd_block *block,
 256                                               struct request *req)
 257 {
 258         struct dasd_fba_private *private;
 259         unsigned long *idaws;
 260         struct LO_fba_data *LO_data;
 261         struct dasd_ccw_req *cqr;
 262         struct ccw1 *ccw;
 263         struct req_iterator iter;
 264         struct bio_vec *bv;
 265         char *dst;
 266         int count, cidaw, cplength, datasize;
 267         sector_t recid, first_rec, last_rec;
 268         unsigned int blksize, off;
 269         unsigned char cmd;
 270
 271         private = (struct dasd_fba_private *) block->base->private;
 272         if (rq_data_dir(req) == READ) {
 273                 cmd = DASD_FBA_CCW_READ;
 274         } else if (rq_data_dir(req) == WRITE) {
 275                 cmd = DASD_FBA_CCW_WRITE;
 276         } else
 277                 return ERR_PTR(-EINVAL);
 278         blksize = block->bp_block;
 279         /* Calculate record id of first and last block. */
 280         first_rec = blk_rq_pos(req) >> block->s2b_shift;
 281         last_rec =
 282                 (blk_rq_pos(req) + blk_rq_sectors(req) - 1) >> block->s2b_shift;
 283         /* Check struct bio and count the number of blocks for the request. */
 284         count = 0;
 285         cidaw = 0;
 286         rq_for_each_segment(bv, req, iter) {
 287                 if (bv->bv_len & (blksize - 1))
 288                         /* Fba can only do full blocks. */
 289                         return ERR_PTR(-EINVAL);
 290                 count += bv->bv_len >> (block->s2b_shift + 9);
 291 #if defined(CONFIG_64BIT)
 292                 if (idal_is_needed (page_address(bv->bv_page), bv->bv_len))
 293                         cidaw += bv->bv_len / blksize;
 294 #endif
 295         }
 296         /* Paranoia. */
 297         if (count != last_rec - first_rec + 1)
 298                 return ERR_PTR(-EINVAL);
 299         /* 1x define extent + 1x locate record + number of blocks */
 300         cplength = 2 + count;
 301         /* 1x define extent + 1x locate record */
 302         datasize = sizeof(struct DE_fba_data) + sizeof(struct LO_fba_data) +
 303                 cidaw * sizeof(unsigned long);
 304         /*
 305          * Find out number of additional locate record ccws if the device
 306          * can't do data chaining.
 307          */
 308         if (private->rdc_data.mode.bits.data_chain == 0) {
 309                 cplength += count - 1;
 310                 datasize += (count - 1)*sizeof(struct LO_fba_data);
 311         }
 312         /* Allocate the ccw request. */
 313         cqr = dasd_smalloc_request(DASD_FBA_MAGIC, cplength, datasize, memdev);
 314         if (IS_ERR(cqr))
 315                 return cqr;
 316         ccw = cqr->cpaddr;
 317         /* First ccw is define extent. */
 318         define_extent(ccw++, cqr->data, rq_data_dir(req),
 319                       block->bp_block, blk_rq_pos(req), blk_rq_sectors(req));
 320         /* Build locate_record + read/write ccws. */
 321         idaws = (unsigned long *) (cqr->data + sizeof(struct DE_fba_data));
 322         LO_data = (struct LO_fba_data *) (idaws + cidaw);
 323         /* Locate record for all blocks for smart devices. */
 324         if (private->rdc_data.mode.bits.data_chain != 0) {
 325                 ccw[-1].flags |= CCW_FLAG_CC;
 326                 locate_record(ccw++, LO_data++, rq_data_dir(req), 0, count);
 327         }
 328         recid = first_rec;
 329         rq_for_each_segment(bv, req, iter) {
 330                 dst = page_address(bv->bv_page) + bv->bv_offset;
 331                 if (dasd_page_cache) {
 332                         char *copy = kmem_cache_alloc(dasd_page_cache,
 333                                                       GFP_DMA | __GFP_NOWARN);
 334                         if (copy && rq_data_dir(req) == WRITE)
 335                                 memcpy(copy + bv->bv_offset, dst, bv->bv_len);
 336                         if (copy)
 337                                 dst = copy + bv->bv_offset;
 338                 }
 339                 for (off = 0; off < bv->bv_len; off += blksize) {
 340                         /* Locate record for stupid devices. */
 341                         if (private->rdc_data.mode.bits.data_chain == 0) {
 342                                 ccw[-1].flags |= CCW_FLAG_CC;
 343                                 locate_record(ccw, LO_data++,
 344                                               rq_data_dir(req),
 345                                               recid - first_rec, 1);
 346                                 ccw->flags = CCW_FLAG_CC;
 347                                 ccw++;
 348                         } else {
 349                                 if (recid > first_rec)
 350                                         ccw[-1].flags |= CCW_FLAG_DC;
 351                                 else
 352                                         ccw[-1].flags |= CCW_FLAG_CC;
 353                         }
 354                         ccw->cmd_code = cmd;
 355                         ccw->count = block->bp_block;
 356                         if (idal_is_needed(dst, blksize)) {
 357                                 ccw->cda = (__u32)(addr_t) idaws;
 358                                 ccw->flags = CCW_FLAG_IDA;
 359                                 idaws = idal_create_words(idaws, dst, blksize);
 360                         } else {
 361                                 ccw->cda = (__u32)(addr_t) dst;
 362                                 ccw->flags = 0;
 363                         }
 364                         ccw++;
 365                         dst += blksize;
 366                         recid++;
 367                 }
 368         }
 369         if (blk_noretry_request(req) ||
 370             block->base->features & DASD_FEATURE_FAILFAST)
 371                 set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
 372         cqr->startdev = memdev;
 373         cqr->memdev = memdev;
 374         cqr->block = block;
 375         cqr->expires = memdev->default_expires * HZ;    /* default 5 minutes */
 376         cqr->retries = 32;
 377         cqr->buildclk = get_clock();
 378         cqr->status = DASD_CQR_FILLED;
 379         return cqr;
 380 }
 381
 382 static int
 383 dasd_fba_free_cp(struct dasd_ccw_req *cqr, struct request *req)
 384 {
 385         struct dasd_fba_private *private;
 386         struct ccw1 *ccw;
 387         struct req_iterator iter;
 388         struct bio_vec *bv;
 389         char *dst, *cda;
 390         unsigned int blksize, off;
 391         int status;
 392
 393         if (!dasd_page_cache)
 394                 goto out;
 395         private = (struct dasd_fba_private *) cqr->block->base->private;
 396         blksize = cqr->block->bp_block;
 397         ccw = cqr->cpaddr;
 398         /* Skip over define extent & locate record. */
 399         ccw++;
 400         if (private->rdc_data.mode.bits.data_chain != 0)
 401                 ccw++;
 402         rq_for_each_segment(bv, req, iter) {
 403                 dst = page_address(bv->bv_page) + bv->bv_offset;
 404                 for (off = 0; off < bv->bv_len; off += blksize) {
 405                         /* Skip locate record. */
 406                         if (private->rdc_data.mode.bits.data_chain == 0)
 407                                 ccw++;
 408                         if (dst) {
 409                                 if (ccw->flags & CCW_FLAG_IDA)
 410                                         cda = *((char **)((addr_t) ccw->cda));
 411                                 else
 412                                         cda = (char *)((addr_t) ccw->cda);
 413                                 if (dst != cda) {
 414                                         if (rq_data_dir(req) == READ)
 415                                                 memcpy(dst, cda, bv->bv_len);
 416                                         kmem_cache_free(dasd_page_cache,
 417                                             (void *)((addr_t)cda & PAGE_MASK));
 418                                 }
 419                                 dst = NULL;
 420                         }
 421                         ccw++;
 422                 }
 423         }
 424 out:
 425         status = cqr->status == DASD_CQR_DONE;
 426         dasd_sfree_request(cqr, cqr->memdev);
 427         return status;
 428 }
 429
 430 static void dasd_fba_handle_terminated_request(struct dasd_ccw_req *cqr)
 431 {
 432         cqr->status = DASD_CQR_FILLED;
 433 };
 434
 435 static int
 436 dasd_fba_fill_info(struct dasd_device * device,
 437                    struct dasd_information2_t * info)
 438 {
 439         info->label_block = 1;
 440         info->FBA_layout = 1;
 441         info->format = DASD_FORMAT_LDL;
 442         info->characteristics_size = sizeof(struct dasd_fba_characteristics);
 443         memcpy(info->characteristics,
 444                &((struct dasd_fba_private *) device->private)->rdc_data,
 445                sizeof (struct dasd_fba_characteristics));
 446         info->confdata_size = 0;
 447         return 0;
 448 }
 449
 450 static void
 451 dasd_fba_dump_sense_dbf(struct dasd_device *device, struct irb *irb,
 452                         char *reason)
 453 {
 454         u64 *sense;
 455
 456         sense = (u64 *) dasd_get_sense(irb);
 457         if (sense) {
 458                 DBF_DEV_EVENT(DBF_EMERG, device,
 459                               "%s: %s %02x%02x%02x %016llx %016llx %016llx "
 460                               "%016llx", reason,
 461                               scsw_is_tm(&irb->scsw) ? "t" : "c",
 462                               scsw_cc(&irb->scsw), scsw_cstat(&irb->scsw),
 463                               scsw_dstat(&irb->scsw), sense[0], sense[1],
 464                               sense[2], sense[3]);
 465         } else {
 466                 DBF_DEV_EVENT(DBF_EMERG, device, "%s",
 467                               "SORRY - NO VALID SENSE AVAILABLE\n");
 468         }
 469 }
 470
 471
 472 static void
 473 dasd_fba_dump_sense(struct dasd_device *device, struct dasd_ccw_req * req,
 474                     struct irb *irb)
 475 {
 476         char *page;
 477         struct ccw1 *act, *end, *last;
 478         int len, sl, sct, count;
 479
 480         page = (char *) get_zeroed_page(GFP_ATOMIC);
 481         if (page == NULL) {
 482                 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
 483                             "No memory to dump sense data");
 484                 return;
 485         }
 486         len = sprintf(page, KERN_ERR PRINTK_HEADER
 487                       " I/O status report for device %s:\n",
 488                       dev_name(&device->cdev->dev));
 489         len += sprintf(page + len, KERN_ERR PRINTK_HEADER
 490                        " in req: %p CS: 0x%02X DS: 0x%02X\n", req,
 491                        irb->scsw.cmd.cstat, irb->scsw.cmd.dstat);
 492         len += sprintf(page + len, KERN_ERR PRINTK_HEADER
 493                        " device %s: Failing CCW: %p\n",
 494                        dev_name(&device->cdev->dev),
 495                        (void *) (addr_t) irb->scsw.cmd.cpa);
 496         if (irb->esw.esw0.erw.cons) {
 497                 for (sl = 0; sl < 4; sl++) {
 498                         len += sprintf(page + len, KERN_ERR PRINTK_HEADER
 499                                        " Sense(hex) %2d-%2d:",
 500                                        (8 * sl), ((8 * sl) + 7));
 501
 502                         for (sct = 0; sct < 8; sct++) {
 503                                 len += sprintf(page + len, " %02x",
 504                                                irb->ecw[8 * sl + sct]);
 505                         }
 506                         len += sprintf(page + len, "\n");
 507                 }
 508         } else {
 509                 len += sprintf(page + len, KERN_ERR PRINTK_HEADER
 510                                " SORRY - NO VALID SENSE AVAILABLE\n");
 511         }
 512         printk(KERN_ERR "%s", page);
 513
 514         /* dump the Channel Program */
 515         /* print first CCWs (maximum 8) */
 516         act = req->cpaddr;
 517         for (last = act; last->flags & (CCW_FLAG_CC | CCW_FLAG_DC); last++);
 518         end = min(act + 8, last);
 519         len = sprintf(page, KERN_ERR PRINTK_HEADER
 520                       " Related CP in req: %p\n", req);
 521         while (act <= end) {
 522                 len += sprintf(page + len, KERN_ERR PRINTK_HEADER
 523                                " CCW %p: %08X %08X DAT:",
 524                                act, ((int *) act)[0], ((int *) act)[1]);
 525                 for (count = 0; count < 32 && count < act->count;
 526                      count += sizeof(int))
 527                         len += sprintf(page + len, " %08X",
 528                                        ((int *) (addr_t) act->cda)
 529                                        [(count>>2)]);
 530                 len += sprintf(page + len, "\n");
 531                 act++;
 532         }
 533         printk(KERN_ERR "%s", page);
 534
 535
 536         /* print failing CCW area */
 537         len = 0;
 538         if (act <  ((struct ccw1 *)(addr_t) irb->scsw.cmd.cpa) - 2) {
 539                 act = ((struct ccw1 *)(addr_t) irb->scsw.cmd.cpa) - 2;
 540                 len += sprintf(page + len, KERN_ERR PRINTK_HEADER "......\n");
 541         }
 542         end = min((struct ccw1 *)(addr_t) irb->scsw.cmd.cpa + 2, last);
 543         while (act <= end) {
 544                 len += sprintf(page + len, KERN_ERR PRINTK_HEADER
 545                                " CCW %p: %08X %08X DAT:",
 546                                act, ((int *) act)[0], ((int *) act)[1]);
 547                 for (count = 0; count < 32 && count < act->count;
 548                      count += sizeof(int))
 549                         len += sprintf(page + len, " %08X",
 550                                        ((int *) (addr_t) act->cda)
 551                                        [(count>>2)]);
 552                 len += sprintf(page + len, "\n");
 553                 act++;
 554         }
 555
 556         /* print last CCWs */
 557         if (act <  last - 2) {
 558                 act = last - 2;
 559                 len += sprintf(page + len, KERN_ERR PRINTK_HEADER "......\n");
 560         }
 561         while (act <= last) {
 562                 len += sprintf(page + len, KERN_ERR PRINTK_HEADER
 563                                " CCW %p: %08X %08X DAT:",
 564                                act, ((int *) act)[0], ((int *) act)[1]);
 565                 for (count = 0; count < 32 && count < act->count;
 566                      count += sizeof(int))
 567                         len += sprintf(page + len, " %08X",
 568                                        ((int *) (addr_t) act->cda)
 569                                        [(count>>2)]);
 570                 len += sprintf(page + len, "\n");
 571                 act++;
 572         }
 573         if (len > 0)
 574                 printk(KERN_ERR "%s", page);
 575         free_page((unsigned long) page);
 576 }
 577
 578 /*
 579  * max_blocks is dependent on the amount of storage that is available
 580  * in the static io buffer for each device. Currently each device has
 581  * 8192 bytes (=2 pages). For 64 bit one dasd_mchunkt_t structure has
 582  * 24 bytes, the struct dasd_ccw_req has 136 bytes and each block can use
 583  * up to 16 bytes (8 for the ccw and 8 for the idal pointer). In
 584  * addition we have one define extent ccw + 16 bytes of data and a
 585  * locate record ccw for each block (stupid devices!) + 16 bytes of data.
 586  * That makes:
 587  * (8192 - 24 - 136 - 8 - 16) / 40 = 200.2 blocks at maximum.
 588  * We want to fit two into the available memory so that we can immediately
 589  * start the next request if one finishes off. That makes 100.1 blocks
 590  * for one request. Give a little safety and the result is 96.
 591  */
 592 static struct dasd_discipline dasd_fba_discipline = {
 593         .owner = THIS_MODULE,
 594         .name = "FBA ",
 595         .ebcname = "FBA ",
 596         .max_blocks = 96,
 597         .check_device = dasd_fba_check_characteristics,
 598         .do_analysis = dasd_fba_do_analysis,
 599         .fill_geometry = dasd_fba_fill_geometry,
 600         .start_IO = dasd_start_IO,
 601         .term_IO = dasd_term_IO,
 602         .handle_terminated_request = dasd_fba_handle_terminated_request,
 603         .erp_action = dasd_fba_erp_action,
 604         .erp_postaction = dasd_fba_erp_postaction,
 605         .handle_unsolicited_interrupt = dasd_fba_handle_unsolicited_interrupt,
 606         .build_cp = dasd_fba_build_cp,
 607         .free_cp = dasd_fba_free_cp,
 608         .dump_sense = dasd_fba_dump_sense,
 609         .dump_sense_dbf = dasd_fba_dump_sense_dbf,
 610         .fill_info = dasd_fba_fill_info,
 611 };
 612
 613 static int __init
 614 dasd_fba_init(void)
 615 {
 616         int ret;
 617
 618         ASCEBC(dasd_fba_discipline.ebcname, 4);
 619         ret = ccw_driver_register(&dasd_fba_driver);
 620         if (!ret)
 621                 wait_for_device_probe();
 622
 623         return ret;
 624 }
 625
 626 static void __exit
 627 dasd_fba_cleanup(void)
 628 {
 629         ccw_driver_unregister(&dasd_fba_driver);
 630 }
 631
 632 module_init(dasd_fba_init);
 633 module_exit(dasd_fba_cleanup);