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         .path_event  = dasd_generic_path_event,
  77         .freeze      = dasd_generic_pm_freeze,
  78         .thaw        = dasd_generic_restore_device,
  79         .restore     = dasd_generic_restore_device,
  80 };
  81
  82 static void
  83 define_extent(struct ccw1 * ccw, struct DE_fba_data *data, int rw,
  84               int blksize, int beg, int nr)
  85 {
  86         ccw->cmd_code = DASD_FBA_CCW_DEFINE_EXTENT;
  87         ccw->flags = 0;
  88         ccw->count = 16;
  89         ccw->cda = (__u32) __pa(data);
  90         memset(data, 0, sizeof (struct DE_fba_data));
  91         if (rw == WRITE)
  92                 (data->mask).perm = 0x0;
  93         else if (rw == READ)
  94                 (data->mask).perm = 0x1;
  95         else
  96                 data->mask.perm = 0x2;
  97         data->blk_size = blksize;
  98         data->ext_loc = beg;
  99         data->ext_end = nr - 1;
 100 }
 101
 102 static void
 103 locate_record(struct ccw1 * ccw, struct LO_fba_data *data, int rw,
 104               int block_nr, int block_ct)
 105 {
 106         ccw->cmd_code = DASD_FBA_CCW_LOCATE;
 107         ccw->flags = 0;
 108         ccw->count = 8;
 109         ccw->cda = (__u32) __pa(data);
 110         memset(data, 0, sizeof (struct LO_fba_data));
 111         if (rw == WRITE)
 112                 data->operation.cmd = 0x5;
 113         else if (rw == READ)
 114                 data->operation.cmd = 0x6;
 115         else
 116                 data->operation.cmd = 0x8;
 117         data->blk_nr = block_nr;
 118         data->blk_ct = block_ct;
 119 }
 120
 121 static int
 122 dasd_fba_check_characteristics(struct dasd_device *device)
 123 {
 124         struct dasd_block *block;
 125         struct dasd_fba_private *private;
 126         struct ccw_device *cdev = device->cdev;
 127         int rc;
 128         int readonly;
 129
 130         private = (struct dasd_fba_private *) device->private;
 131         if (!private) {
 132                 private = kzalloc(sizeof(*private), GFP_KERNEL | GFP_DMA);
 133                 if (!private) {
 134                         dev_warn(&device->cdev->dev,
 135                                  "Allocating memory for private DASD "
 136                                  "data failed\n");
 137                         return -ENOMEM;
 138                 }
 139                 device->private = (void *) private;
 140         } else {
 141                 memset(private, 0, sizeof(*private));
 142         }
 143         block = dasd_alloc_block();
 144         if (IS_ERR(block)) {
 145                 DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s", "could not allocate "
 146                                 "dasd block structure");
 147                 device->private = NULL;
 148                 kfree(private);
 149                 return PTR_ERR(block);
 150         }
 151         device->block = block;
 152         block->base = device;
 153
 154         /* Read Device Characteristics */
 155         rc = dasd_generic_read_dev_chars(device, DASD_FBA_MAGIC,
 156                                          &private->rdc_data, 32);
 157         if (rc) {
 158                 DBF_EVENT_DEVID(DBF_WARNING, cdev, "Read device "
 159                                 "characteristics returned error %d", rc);
 160                 device->block = NULL;
 161                 dasd_free_block(block);
 162                 device->private = NULL;
 163                 kfree(private);
 164                 return rc;
 165         }
 166
 167         device->default_expires = DASD_EXPIRES;
 168         device->path_data.opm = LPM_ANYPATH;
 169
 170         readonly = dasd_device_is_ro(device);
 171         if (readonly)
 172                 set_bit(DASD_FLAG_DEVICE_RO, &device->flags);
 173
 174         dev_info(&device->cdev->dev,
 175                  "New FBA DASD %04X/%02X (CU %04X/%02X) with %d MB "
 176                  "and %d B/blk%s\n",
 177                  cdev->id.dev_type,
 178                  cdev->id.dev_model,
 179                  cdev->id.cu_type,
 180                  cdev->id.cu_model,
 181                  ((private->rdc_data.blk_bdsa *
 182                    (private->rdc_data.blk_size >> 9)) >> 11),
 183                  private->rdc_data.blk_size,
 184                  readonly ? ", read-only device" : "");
 185         return 0;
 186 }
 187
 188 static int dasd_fba_do_analysis(struct dasd_block *block)
 189 {
 190         struct dasd_fba_private *private;
 191         int sb, rc;
 192
 193         private = (struct dasd_fba_private *) block->base->private;
 194         rc = dasd_check_blocksize(private->rdc_data.blk_size);
 195         if (rc) {
 196                 DBF_DEV_EVENT(DBF_WARNING, block->base, "unknown blocksize %d",
 197                             private->rdc_data.blk_size);
 198                 return rc;
 199         }
 200         block->blocks = private->rdc_data.blk_bdsa;
 201         block->bp_block = private->rdc_data.blk_size;
 202         block->s2b_shift = 0;   /* bits to shift 512 to get a block */
 203         for (sb = 512; sb < private->rdc_data.blk_size; sb = sb << 1)
 204                 block->s2b_shift++;
 205         return 0;
 206 }
 207
 208 static int dasd_fba_fill_geometry(struct dasd_block *block,
 209                                   struct hd_geometry *geo)
 210 {
 211         if (dasd_check_blocksize(block->bp_block) != 0)
 212                 return -EINVAL;
 213         geo->cylinders = (block->blocks << block->s2b_shift) >> 10;
 214         geo->heads = 16;
 215         geo->sectors = 128 >> block->s2b_shift;
 216         return 0;
 217 }
 218
 219 static dasd_erp_fn_t
 220 dasd_fba_erp_action(struct dasd_ccw_req * cqr)
 221 {
 222         return dasd_default_erp_action;
 223 }
 224
 225 static dasd_erp_fn_t
 226 dasd_fba_erp_postaction(struct dasd_ccw_req * cqr)
 227 {
 228         if (cqr->function == dasd_default_erp_action)
 229                 return dasd_default_erp_postaction;
 230
 231         DBF_DEV_EVENT(DBF_WARNING, cqr->startdev, "unknown ERP action %p",
 232                     cqr->function);
 233         return NULL;
 234 }
 235
 236 static void dasd_fba_check_for_device_change(struct dasd_device *device,
 237                                              struct dasd_ccw_req *cqr,
 238                                              struct irb *irb)
 239 {
 240         char mask;
 241
 242         /* first of all check for state change pending interrupt */
 243         mask = DEV_STAT_ATTENTION | DEV_STAT_DEV_END | DEV_STAT_UNIT_EXCEP;
 244         if ((irb->scsw.cmd.dstat & mask) == mask)
 245                 dasd_generic_handle_state_change(device);
 246 };
 247
 248 static struct dasd_ccw_req *dasd_fba_build_cp(struct dasd_device * memdev,
 249                                               struct dasd_block *block,
 250                                               struct request *req)
 251 {
 252         struct dasd_fba_private *private;
 253         unsigned long *idaws;
 254         struct LO_fba_data *LO_data;
 255         struct dasd_ccw_req *cqr;
 256         struct ccw1 *ccw;
 257         struct req_iterator iter;
 258         struct bio_vec *bv;
 259         char *dst;
 260         int count, cidaw, cplength, datasize;
 261         sector_t recid, first_rec, last_rec;
 262         unsigned int blksize, off;
 263         unsigned char cmd;
 264
 265         private = (struct dasd_fba_private *) block->base->private;
 266         if (rq_data_dir(req) == READ) {
 267                 cmd = DASD_FBA_CCW_READ;
 268         } else if (rq_data_dir(req) == WRITE) {
 269                 cmd = DASD_FBA_CCW_WRITE;
 270         } else
 271                 return ERR_PTR(-EINVAL);
 272         blksize = block->bp_block;
 273         /* Calculate record id of first and last block. */
 274         first_rec = blk_rq_pos(req) >> block->s2b_shift;
 275         last_rec =
 276                 (blk_rq_pos(req) + blk_rq_sectors(req) - 1) >> block->s2b_shift;
 277         /* Check struct bio and count the number of blocks for the request. */
 278         count = 0;
 279         cidaw = 0;
 280         rq_for_each_segment(bv, req, iter) {
 281                 if (bv->bv_len & (blksize - 1))
 282                         /* Fba can only do full blocks. */
 283                         return ERR_PTR(-EINVAL);
 284                 count += bv->bv_len >> (block->s2b_shift + 9);
 285 #if defined(CONFIG_64BIT)
 286                 if (idal_is_needed (page_address(bv->bv_page), bv->bv_len))
 287                         cidaw += bv->bv_len / blksize;
 288 #endif
 289         }
 290         /* Paranoia. */
 291         if (count != last_rec - first_rec + 1)
 292                 return ERR_PTR(-EINVAL);
 293         /* 1x define extent + 1x locate record + number of blocks */
 294         cplength = 2 + count;
 295         /* 1x define extent + 1x locate record */
 296         datasize = sizeof(struct DE_fba_data) + sizeof(struct LO_fba_data) +
 297                 cidaw * sizeof(unsigned long);
 298         /*
 299          * Find out number of additional locate record ccws if the device
 300          * can't do data chaining.
 301          */
 302         if (private->rdc_data.mode.bits.data_chain == 0) {
 303                 cplength += count - 1;
 304                 datasize += (count - 1)*sizeof(struct LO_fba_data);
 305         }
 306         /* Allocate the ccw request. */
 307         cqr = dasd_smalloc_request(DASD_FBA_MAGIC, cplength, datasize, memdev);
 308         if (IS_ERR(cqr))
 309                 return cqr;
 310         ccw = cqr->cpaddr;
 311         /* First ccw is define extent. */
 312         define_extent(ccw++, cqr->data, rq_data_dir(req),
 313                       block->bp_block, blk_rq_pos(req), blk_rq_sectors(req));
 314         /* Build locate_record + read/write ccws. */
 315         idaws = (unsigned long *) (cqr->data + sizeof(struct DE_fba_data));
 316         LO_data = (struct LO_fba_data *) (idaws + cidaw);
 317         /* Locate record for all blocks for smart devices. */
 318         if (private->rdc_data.mode.bits.data_chain != 0) {
 319                 ccw[-1].flags |= CCW_FLAG_CC;
 320                 locate_record(ccw++, LO_data++, rq_data_dir(req), 0, count);
 321         }
 322         recid = first_rec;
 323         rq_for_each_segment(bv, req, iter) {
 324                 dst = page_address(bv->bv_page) + bv->bv_offset;
 325                 if (dasd_page_cache) {
 326                         char *copy = kmem_cache_alloc(dasd_page_cache,
 327                                                       GFP_DMA | __GFP_NOWARN);
 328                         if (copy && rq_data_dir(req) == WRITE)
 329                                 memcpy(copy + bv->bv_offset, dst, bv->bv_len);
 330                         if (copy)
 331                                 dst = copy + bv->bv_offset;
 332                 }
 333                 for (off = 0; off < bv->bv_len; off += blksize) {
 334                         /* Locate record for stupid devices. */
 335                         if (private->rdc_data.mode.bits.data_chain == 0) {
 336                                 ccw[-1].flags |= CCW_FLAG_CC;
 337                                 locate_record(ccw, LO_data++,
 338                                               rq_data_dir(req),
 339                                               recid - first_rec, 1);
 340                                 ccw->flags = CCW_FLAG_CC;
 341                                 ccw++;
 342                         } else {
 343                                 if (recid > first_rec)
 344                                         ccw[-1].flags |= CCW_FLAG_DC;
 345                                 else
 346                                         ccw[-1].flags |= CCW_FLAG_CC;
 347                         }
 348                         ccw->cmd_code = cmd;
 349                         ccw->count = block->bp_block;
 350                         if (idal_is_needed(dst, blksize)) {
 351                                 ccw->cda = (__u32)(addr_t) idaws;
 352                                 ccw->flags = CCW_FLAG_IDA;
 353                                 idaws = idal_create_words(idaws, dst, blksize);
 354                         } else {
 355                                 ccw->cda = (__u32)(addr_t) dst;
 356                                 ccw->flags = 0;
 357                         }
 358                         ccw++;
 359                         dst += blksize;
 360                         recid++;
 361                 }
 362         }
 363         if (blk_noretry_request(req) ||
 364             block->base->features & DASD_FEATURE_FAILFAST)
 365                 set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
 366         cqr->startdev = memdev;
 367         cqr->memdev = memdev;
 368         cqr->block = block;
 369         cqr->expires = memdev->default_expires * HZ;    /* default 5 minutes */
 370         cqr->retries = 32;
 371         cqr->buildclk = get_clock();
 372         cqr->status = DASD_CQR_FILLED;
 373         return cqr;
 374 }
 375
 376 static int
 377 dasd_fba_free_cp(struct dasd_ccw_req *cqr, struct request *req)
 378 {
 379         struct dasd_fba_private *private;
 380         struct ccw1 *ccw;
 381         struct req_iterator iter;
 382         struct bio_vec *bv;
 383         char *dst, *cda;
 384         unsigned int blksize, off;
 385         int status;
 386
 387         if (!dasd_page_cache)
 388                 goto out;
 389         private = (struct dasd_fba_private *) cqr->block->base->private;
 390         blksize = cqr->block->bp_block;
 391         ccw = cqr->cpaddr;
 392         /* Skip over define extent & locate record. */
 393         ccw++;
 394         if (private->rdc_data.mode.bits.data_chain != 0)
 395                 ccw++;
 396         rq_for_each_segment(bv, req, iter) {
 397                 dst = page_address(bv->bv_page) + bv->bv_offset;
 398                 for (off = 0; off < bv->bv_len; off += blksize) {
 399                         /* Skip locate record. */
 400                         if (private->rdc_data.mode.bits.data_chain == 0)
 401                                 ccw++;
 402                         if (dst) {
 403                                 if (ccw->flags & CCW_FLAG_IDA)
 404                                         cda = *((char **)((addr_t) ccw->cda));
 405                                 else
 406                                         cda = (char *)((addr_t) ccw->cda);
 407                                 if (dst != cda) {
 408                                         if (rq_data_dir(req) == READ)
 409                                                 memcpy(dst, cda, bv->bv_len);
 410                                         kmem_cache_free(dasd_page_cache,
 411                                             (void *)((addr_t)cda & PAGE_MASK));
 412                                 }
 413                                 dst = NULL;
 414                         }
 415                         ccw++;
 416                 }
 417         }
 418 out:
 419         status = cqr->status == DASD_CQR_DONE;
 420         dasd_sfree_request(cqr, cqr->memdev);
 421         return status;
 422 }
 423
 424 static void dasd_fba_handle_terminated_request(struct dasd_ccw_req *cqr)
 425 {
 426         cqr->status = DASD_CQR_FILLED;
 427 };
 428
 429 static int
 430 dasd_fba_fill_info(struct dasd_device * device,
 431                    struct dasd_information2_t * info)
 432 {
 433         info->label_block = 1;
 434         info->FBA_layout = 1;
 435         info->format = DASD_FORMAT_LDL;
 436         info->characteristics_size = sizeof(struct dasd_fba_characteristics);
 437         memcpy(info->characteristics,
 438                &((struct dasd_fba_private *) device->private)->rdc_data,
 439                sizeof (struct dasd_fba_characteristics));
 440         info->confdata_size = 0;
 441         return 0;
 442 }
 443
 444 static void
 445 dasd_fba_dump_sense_dbf(struct dasd_device *device, struct irb *irb,
 446                         char *reason)
 447 {
 448         u64 *sense;
 449
 450         sense = (u64 *) dasd_get_sense(irb);
 451         if (sense) {
 452                 DBF_DEV_EVENT(DBF_EMERG, device,
 453                               "%s: %s %02x%02x%02x %016llx %016llx %016llx "
 454                               "%016llx", reason,
 455                               scsw_is_tm(&irb->scsw) ? "t" : "c",
 456                               scsw_cc(&irb->scsw), scsw_cstat(&irb->scsw),
 457                               scsw_dstat(&irb->scsw), sense[0], sense[1],
 458                               sense[2], sense[3]);
 459         } else {
 460                 DBF_DEV_EVENT(DBF_EMERG, device, "%s",
 461                               "SORRY - NO VALID SENSE AVAILABLE\n");
 462         }
 463 }
 464
 465
 466 static void
 467 dasd_fba_dump_sense(struct dasd_device *device, struct dasd_ccw_req * req,
 468                     struct irb *irb)
 469 {
 470         char *page;
 471         struct ccw1 *act, *end, *last;
 472         int len, sl, sct, count;
 473
 474         page = (char *) get_zeroed_page(GFP_ATOMIC);
 475         if (page == NULL) {
 476                 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
 477                             "No memory to dump sense data");
 478                 return;
 479         }
 480         len = sprintf(page, KERN_ERR PRINTK_HEADER
 481                       " I/O status report for device %s:\n",
 482                       dev_name(&device->cdev->dev));
 483         len += sprintf(page + len, KERN_ERR PRINTK_HEADER
 484                        " in req: %p CS: 0x%02X DS: 0x%02X\n", req,
 485                        irb->scsw.cmd.cstat, irb->scsw.cmd.dstat);
 486         len += sprintf(page + len, KERN_ERR PRINTK_HEADER
 487                        " device %s: Failing CCW: %p\n",
 488                        dev_name(&device->cdev->dev),
 489                        (void *) (addr_t) irb->scsw.cmd.cpa);
 490         if (irb->esw.esw0.erw.cons) {
 491                 for (sl = 0; sl < 4; sl++) {
 492                         len += sprintf(page + len, KERN_ERR PRINTK_HEADER
 493                                        " Sense(hex) %2d-%2d:",
 494                                        (8 * sl), ((8 * sl) + 7));
 495
 496                         for (sct = 0; sct < 8; sct++) {
 497                                 len += sprintf(page + len, " %02x",
 498                                                irb->ecw[8 * sl + sct]);
 499                         }
 500                         len += sprintf(page + len, "\n");
 501                 }
 502         } else {
 503                 len += sprintf(page + len, KERN_ERR PRINTK_HEADER
 504                                " SORRY - NO VALID SENSE AVAILABLE\n");
 505         }
 506         printk(KERN_ERR "%s", page);
 507
 508         /* dump the Channel Program */
 509         /* print first CCWs (maximum 8) */
 510         act = req->cpaddr;
 511         for (last = act; last->flags & (CCW_FLAG_CC | CCW_FLAG_DC); last++);
 512         end = min(act + 8, last);
 513         len = sprintf(page, KERN_ERR PRINTK_HEADER
 514                       " Related CP in req: %p\n", req);
 515         while (act <= end) {
 516                 len += sprintf(page + len, KERN_ERR PRINTK_HEADER
 517                                " CCW %p: %08X %08X DAT:",
 518                                act, ((int *) act)[0], ((int *) act)[1]);
 519                 for (count = 0; count < 32 && count < act->count;
 520                      count += sizeof(int))
 521                         len += sprintf(page + len, " %08X",
 522                                        ((int *) (addr_t) act->cda)
 523                                        [(count>>2)]);
 524                 len += sprintf(page + len, "\n");
 525                 act++;
 526         }
 527         printk(KERN_ERR "%s", page);
 528
 529
 530         /* print failing CCW area */
 531         len = 0;
 532         if (act <  ((struct ccw1 *)(addr_t) irb->scsw.cmd.cpa) - 2) {
 533                 act = ((struct ccw1 *)(addr_t) irb->scsw.cmd.cpa) - 2;
 534                 len += sprintf(page + len, KERN_ERR PRINTK_HEADER "......\n");
 535         }
 536         end = min((struct ccw1 *)(addr_t) irb->scsw.cmd.cpa + 2, last);
 537         while (act <= end) {
 538                 len += sprintf(page + len, KERN_ERR PRINTK_HEADER
 539                                " CCW %p: %08X %08X DAT:",
 540                                act, ((int *) act)[0], ((int *) act)[1]);
 541                 for (count = 0; count < 32 && count < act->count;
 542                      count += sizeof(int))
 543                         len += sprintf(page + len, " %08X",
 544                                        ((int *) (addr_t) act->cda)
 545                                        [(count>>2)]);
 546                 len += sprintf(page + len, "\n");
 547                 act++;
 548         }
 549
 550         /* print last CCWs */
 551         if (act <  last - 2) {
 552                 act = last - 2;
 553                 len += sprintf(page + len, KERN_ERR PRINTK_HEADER "......\n");
 554         }
 555         while (act <= last) {
 556                 len += sprintf(page + len, KERN_ERR PRINTK_HEADER
 557                                " CCW %p: %08X %08X DAT:",
 558                                act, ((int *) act)[0], ((int *) act)[1]);
 559                 for (count = 0; count < 32 && count < act->count;
 560                      count += sizeof(int))
 561                         len += sprintf(page + len, " %08X",
 562                                        ((int *) (addr_t) act->cda)
 563                                        [(count>>2)]);
 564                 len += sprintf(page + len, "\n");
 565                 act++;
 566         }
 567         if (len > 0)
 568                 printk(KERN_ERR "%s", page);
 569         free_page((unsigned long) page);
 570 }
 571
 572 /*
 573  * max_blocks is dependent on the amount of storage that is available
 574  * in the static io buffer for each device. Currently each device has
 575  * 8192 bytes (=2 pages). For 64 bit one dasd_mchunkt_t structure has
 576  * 24 bytes, the struct dasd_ccw_req has 136 bytes and each block can use
 577  * up to 16 bytes (8 for the ccw and 8 for the idal pointer). In
 578  * addition we have one define extent ccw + 16 bytes of data and a
 579  * locate record ccw for each block (stupid devices!) + 16 bytes of data.
 580  * That makes:
 581  * (8192 - 24 - 136 - 8 - 16) / 40 = 200.2 blocks at maximum.
 582  * We want to fit two into the available memory so that we can immediately
 583  * start the next request if one finishes off. That makes 100.1 blocks
 584  * for one request. Give a little safety and the result is 96.
 585  */
 586 static struct dasd_discipline dasd_fba_discipline = {
 587         .owner = THIS_MODULE,
 588         .name = "FBA ",
 589         .ebcname = "FBA ",
 590         .max_blocks = 96,
 591         .check_device = dasd_fba_check_characteristics,
 592         .do_analysis = dasd_fba_do_analysis,
 593         .verify_path = dasd_generic_verify_path,
 594         .fill_geometry = dasd_fba_fill_geometry,
 595         .start_IO = dasd_start_IO,
 596         .term_IO = dasd_term_IO,
 597         .handle_terminated_request = dasd_fba_handle_terminated_request,
 598         .erp_action = dasd_fba_erp_action,
 599         .erp_postaction = dasd_fba_erp_postaction,
 600         .check_for_device_change = dasd_fba_check_for_device_change,
 601         .build_cp = dasd_fba_build_cp,
 602         .free_cp = dasd_fba_free_cp,
 603         .dump_sense = dasd_fba_dump_sense,
 604         .dump_sense_dbf = dasd_fba_dump_sense_dbf,
 605         .fill_info = dasd_fba_fill_info,
 606 };
 607
 608 static int __init
 609 dasd_fba_init(void)
 610 {
 611         int ret;
 612
 613         ASCEBC(dasd_fba_discipline.ebcname, 4);
 614         ret = ccw_driver_register(&dasd_fba_driver);
 615         if (!ret)
 616                 wait_for_device_probe();
 617
 618         return ret;
 619 }
 620
 621 static void __exit
 622 dasd_fba_cleanup(void)
 623 {
 624         ccw_driver_unregister(&dasd_fba_driver);
 625 }
 626
 627 module_init(dasd_fba_init);
 628 module_exit(dasd_fba_cleanup);