drivers/s390/block/dasd_fba.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   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 FBA_DEFAULT_RETRIES 32
  34
  35 #define DASD_FBA_CCW_WRITE 0x41
  36 #define DASD_FBA_CCW_READ 0x42
  37 #define DASD_FBA_CCW_LOCATE 0x43
  38 #define DASD_FBA_CCW_DEFINE_EXTENT 0x63
  39
  40 MODULE_LICENSE("GPL");
  41
  42 static struct dasd_discipline dasd_fba_discipline;
  43 static void *dasd_fba_zero_page;
  44
  45 struct dasd_fba_private {
  46         struct dasd_fba_characteristics rdc_data;
  47 };
  48
  49 static struct ccw_device_id dasd_fba_ids[] = {
  50         { CCW_DEVICE_DEVTYPE (0x6310, 0, 0x9336, 0), .driver_info = 0x1},
  51         { CCW_DEVICE_DEVTYPE (0x3880, 0, 0x3370, 0), .driver_info = 0x2},
  52         { /* end of list */ },
  53 };
  54
  55 MODULE_DEVICE_TABLE(ccw, dasd_fba_ids);
  56
  57 static struct ccw_driver dasd_fba_driver; /* see below */
  58 static int
  59 dasd_fba_probe(struct ccw_device *cdev)
  60 {
  61         return dasd_generic_probe(cdev, &dasd_fba_discipline);
  62 }
  63
  64 static int
  65 dasd_fba_set_online(struct ccw_device *cdev)
  66 {
  67         return dasd_generic_set_online(cdev, &dasd_fba_discipline);
  68 }
  69
  70 static struct ccw_driver dasd_fba_driver = {
  71         .driver = {
  72                 .name   = "dasd-fba",
  73                 .owner  = THIS_MODULE,
  74         },
  75         .ids         = dasd_fba_ids,
  76         .probe       = dasd_fba_probe,
  77         .remove      = dasd_generic_remove,
  78         .set_offline = dasd_generic_set_offline,
  79         .set_online  = dasd_fba_set_online,
  80         .notify      = dasd_generic_notify,
  81         .path_event  = dasd_generic_path_event,
  82         .freeze      = dasd_generic_pm_freeze,
  83         .thaw        = dasd_generic_restore_device,
  84         .restore     = dasd_generic_restore_device,
  85         .int_class   = IRQIO_DAS,
  86 };
  87
  88 static void
  89 define_extent(struct ccw1 * ccw, struct DE_fba_data *data, int rw,
  90               int blksize, int beg, int nr)
  91 {
  92         ccw->cmd_code = DASD_FBA_CCW_DEFINE_EXTENT;
  93         ccw->flags = 0;
  94         ccw->count = 16;
  95         ccw->cda = (__u32) __pa(data);
  96         memset(data, 0, sizeof (struct DE_fba_data));
  97         if (rw == WRITE)
  98                 (data->mask).perm = 0x0;
  99         else if (rw == READ)
 100                 (data->mask).perm = 0x1;
 101         else
 102                 data->mask.perm = 0x2;
 103         data->blk_size = blksize;
 104         data->ext_loc = beg;
 105         data->ext_end = nr - 1;
 106 }
 107
 108 static void
 109 locate_record(struct ccw1 * ccw, struct LO_fba_data *data, int rw,
 110               int block_nr, int block_ct)
 111 {
 112         ccw->cmd_code = DASD_FBA_CCW_LOCATE;
 113         ccw->flags = 0;
 114         ccw->count = 8;
 115         ccw->cda = (__u32) __pa(data);
 116         memset(data, 0, sizeof (struct LO_fba_data));
 117         if (rw == WRITE)
 118                 data->operation.cmd = 0x5;
 119         else if (rw == READ)
 120                 data->operation.cmd = 0x6;
 121         else
 122                 data->operation.cmd = 0x8;
 123         data->blk_nr = block_nr;
 124         data->blk_ct = block_ct;
 125 }
 126
 127 static int
 128 dasd_fba_check_characteristics(struct dasd_device *device)
 129 {
 130         struct dasd_fba_private *private = device->private;
 131         struct ccw_device *cdev = device->cdev;
 132         struct dasd_block *block;
 133         int readonly, rc;
 134
 135         if (!private) {
 136                 private = kzalloc(sizeof(*private), GFP_KERNEL | GFP_DMA);
 137                 if (!private) {
 138                         dev_warn(&device->cdev->dev,
 139                                  "Allocating memory for private DASD "
 140                                  "data failed\n");
 141                         return -ENOMEM;
 142                 }
 143                 device->private = private;
 144         } else {
 145                 memset(private, 0, sizeof(*private));
 146         }
 147         block = dasd_alloc_block();
 148         if (IS_ERR(block)) {
 149                 DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s", "could not allocate "
 150                                 "dasd block structure");
 151                 device->private = NULL;
 152                 kfree(private);
 153                 return PTR_ERR(block);
 154         }
 155         device->block = block;
 156         block->base = device;
 157
 158         /* Read Device Characteristics */
 159         rc = dasd_generic_read_dev_chars(device, DASD_FBA_MAGIC,
 160                                          &private->rdc_data, 32);
 161         if (rc) {
 162                 DBF_EVENT_DEVID(DBF_WARNING, cdev, "Read device "
 163                                 "characteristics returned error %d", rc);
 164                 device->block = NULL;
 165                 dasd_free_block(block);
 166                 device->private = NULL;
 167                 kfree(private);
 168                 return rc;
 169         }
 170
 171         device->default_expires = DASD_EXPIRES;
 172         device->default_retries = FBA_DEFAULT_RETRIES;
 173         dasd_path_set_opm(device, LPM_ANYPATH);
 174
 175         readonly = dasd_device_is_ro(device);
 176         if (readonly)
 177                 set_bit(DASD_FLAG_DEVICE_RO, &device->flags);
 178
 179         /* FBA supports discard, set the according feature bit */
 180         dasd_set_feature(cdev, DASD_FEATURE_DISCARD, 1);
 181
 182         dev_info(&device->cdev->dev,
 183                  "New FBA DASD %04X/%02X (CU %04X/%02X) with %d MB "
 184                  "and %d B/blk%s\n",
 185                  cdev->id.dev_type,
 186                  cdev->id.dev_model,
 187                  cdev->id.cu_type,
 188                  cdev->id.cu_model,
 189                  ((private->rdc_data.blk_bdsa *
 190                    (private->rdc_data.blk_size >> 9)) >> 11),
 191                  private->rdc_data.blk_size,
 192                  readonly ? ", read-only device" : "");
 193         return 0;
 194 }
 195
 196 static int dasd_fba_do_analysis(struct dasd_block *block)
 197 {
 198         struct dasd_fba_private *private = block->base->private;
 199         int sb, rc;
 200
 201         rc = dasd_check_blocksize(private->rdc_data.blk_size);
 202         if (rc) {
 203                 DBF_DEV_EVENT(DBF_WARNING, block->base, "unknown blocksize %d",
 204                             private->rdc_data.blk_size);
 205                 return rc;
 206         }
 207         block->blocks = private->rdc_data.blk_bdsa;
 208         block->bp_block = private->rdc_data.blk_size;
 209         block->s2b_shift = 0;   /* bits to shift 512 to get a block */
 210         for (sb = 512; sb < private->rdc_data.blk_size; sb = sb << 1)
 211                 block->s2b_shift++;
 212         return 0;
 213 }
 214
 215 static int dasd_fba_fill_geometry(struct dasd_block *block,
 216                                   struct hd_geometry *geo)
 217 {
 218         if (dasd_check_blocksize(block->bp_block) != 0)
 219                 return -EINVAL;
 220         geo->cylinders = (block->blocks << block->s2b_shift) >> 10;
 221         geo->heads = 16;
 222         geo->sectors = 128 >> block->s2b_shift;
 223         return 0;
 224 }
 225
 226 static dasd_erp_fn_t
 227 dasd_fba_erp_action(struct dasd_ccw_req * cqr)
 228 {
 229         return dasd_default_erp_action;
 230 }
 231
 232 static dasd_erp_fn_t
 233 dasd_fba_erp_postaction(struct dasd_ccw_req * cqr)
 234 {
 235         if (cqr->function == dasd_default_erp_action)
 236                 return dasd_default_erp_postaction;
 237
 238         DBF_DEV_EVENT(DBF_WARNING, cqr->startdev, "unknown ERP action %p",
 239                     cqr->function);
 240         return NULL;
 241 }
 242
 243 static void dasd_fba_check_for_device_change(struct dasd_device *device,
 244                                              struct dasd_ccw_req *cqr,
 245                                              struct irb *irb)
 246 {
 247         char mask;
 248
 249         /* first of all check for state change pending interrupt */
 250         mask = DEV_STAT_ATTENTION | DEV_STAT_DEV_END | DEV_STAT_UNIT_EXCEP;
 251         if ((irb->scsw.cmd.dstat & mask) == mask)
 252                 dasd_generic_handle_state_change(device);
 253 };
 254
 255
 256 /*
 257  * Builds a CCW with no data payload
 258  */
 259 static void ccw_write_no_data(struct ccw1 *ccw)
 260 {
 261         ccw->cmd_code = DASD_FBA_CCW_WRITE;
 262         ccw->flags |= CCW_FLAG_SLI;
 263         ccw->count = 0;
 264 }
 265
 266 /*
 267  * Builds a CCW that writes only zeroes.
 268  */
 269 static void ccw_write_zero(struct ccw1 *ccw, int count)
 270 {
 271         ccw->cmd_code = DASD_FBA_CCW_WRITE;
 272         ccw->flags |= CCW_FLAG_SLI;
 273         ccw->count = count;
 274         ccw->cda = (__u32) (addr_t) dasd_fba_zero_page;
 275 }
 276
 277 /*
 278  * Helper function to count the amount of necessary CCWs within a given range
 279  * with 4k alignment and command chaining in mind.
 280  */
 281 static int count_ccws(sector_t first_rec, sector_t last_rec,
 282                       unsigned int blocks_per_page)
 283 {
 284         sector_t wz_stop = 0, d_stop = 0;
 285         int cur_pos = 0;
 286         int count = 0;
 287
 288         if (first_rec % blocks_per_page != 0) {
 289                 wz_stop = first_rec + blocks_per_page -
 290                         (first_rec % blocks_per_page) - 1;
 291                 if (wz_stop > last_rec)
 292                         wz_stop = last_rec;
 293                 cur_pos = wz_stop - first_rec + 1;
 294                 count++;
 295         }
 296
 297         if (last_rec - (first_rec + cur_pos) + 1 >= blocks_per_page) {
 298                 if ((last_rec - blocks_per_page + 1) % blocks_per_page != 0)
 299                         d_stop = last_rec - ((last_rec - blocks_per_page + 1) %
 300                                              blocks_per_page);
 301                 else
 302                         d_stop = last_rec;
 303
 304                 cur_pos += d_stop - (first_rec + cur_pos) + 1;
 305                 count++;
 306         }
 307
 308         if (cur_pos == 0 || first_rec + cur_pos - 1 < last_rec)
 309                 count++;
 310
 311         return count;
 312 }
 313
 314 /*
 315  * This function builds a CCW request for block layer discard requests.
 316  * Each page in the z/VM hypervisor that represents certain records of an FBA
 317  * device will be padded with zeros. This is a special behaviour of the WRITE
 318  * command which is triggered when no data payload is added to the CCW.
 319  *
 320  * Note: Due to issues in some z/VM versions, we can't fully utilise this
 321  * special behaviour. We have to keep a 4k (or 8 block) alignment in mind to
 322  * work around those issues and write actual zeroes to the unaligned parts in
 323  * the request. This workaround might be removed in the future.
 324  */
 325 static struct dasd_ccw_req *dasd_fba_build_cp_discard(
 326                                                 struct dasd_device *memdev,
 327                                                 struct dasd_block *block,
 328                                                 struct request *req)
 329 {
 330         struct LO_fba_data *LO_data;
 331         struct dasd_ccw_req *cqr;
 332         struct ccw1 *ccw;
 333
 334         sector_t wz_stop = 0, d_stop = 0;
 335         sector_t first_rec, last_rec;
 336
 337         unsigned int blksize = block->bp_block;
 338         unsigned int blocks_per_page;
 339         int wz_count = 0;
 340         int d_count = 0;
 341         int cur_pos = 0; /* Current position within the extent */
 342         int count = 0;
 343         int cplength;
 344         int datasize;
 345         int nr_ccws;
 346
 347         first_rec = blk_rq_pos(req) >> block->s2b_shift;
 348         last_rec =
 349                 (blk_rq_pos(req) + blk_rq_sectors(req) - 1) >> block->s2b_shift;
 350         count = last_rec - first_rec + 1;
 351
 352         blocks_per_page = BLOCKS_PER_PAGE(blksize);
 353         nr_ccws = count_ccws(first_rec, last_rec, blocks_per_page);
 354
 355         /* define extent + nr_ccws * locate record + nr_ccws * single CCW */
 356         cplength = 1 + 2 * nr_ccws;
 357         datasize = sizeof(struct DE_fba_data) +
 358                 nr_ccws * (sizeof(struct LO_fba_data) + sizeof(struct ccw1));
 359
 360         cqr = dasd_smalloc_request(DASD_FBA_MAGIC, cplength, datasize, memdev,
 361                                    blk_mq_rq_to_pdu(req));
 362         if (IS_ERR(cqr))
 363                 return cqr;
 364
 365         ccw = cqr->cpaddr;
 366
 367         define_extent(ccw++, cqr->data, WRITE, blksize, first_rec, count);
 368         LO_data = cqr->data + sizeof(struct DE_fba_data);
 369
 370         /* First part is not aligned. Calculate range to write zeroes. */
 371         if (first_rec % blocks_per_page != 0) {
 372                 wz_stop = first_rec + blocks_per_page -
 373                         (first_rec % blocks_per_page) - 1;
 374                 if (wz_stop > last_rec)
 375                         wz_stop = last_rec;
 376                 wz_count = wz_stop - first_rec + 1;
 377
 378                 ccw[-1].flags |= CCW_FLAG_CC;
 379                 locate_record(ccw++, LO_data++, WRITE, cur_pos, wz_count);
 380
 381                 ccw[-1].flags |= CCW_FLAG_CC;
 382                 ccw_write_zero(ccw++, wz_count * blksize);
 383
 384                 cur_pos = wz_count;
 385         }
 386
 387         /* We can do proper discard when we've got at least blocks_per_page blocks. */
 388         if (last_rec - (first_rec + cur_pos) + 1 >= blocks_per_page) {
 389                 /* is last record at page boundary? */
 390                 if ((last_rec - blocks_per_page + 1) % blocks_per_page != 0)
 391                         d_stop = last_rec - ((last_rec - blocks_per_page + 1) %
 392                                              blocks_per_page);
 393                 else
 394                         d_stop = last_rec;
 395
 396                 d_count = d_stop - (first_rec + cur_pos) + 1;
 397
 398                 ccw[-1].flags |= CCW_FLAG_CC;
 399                 locate_record(ccw++, LO_data++, WRITE, cur_pos, d_count);
 400
 401                 ccw[-1].flags |= CCW_FLAG_CC;
 402                 ccw_write_no_data(ccw++);
 403
 404                 cur_pos += d_count;
 405         }
 406
 407         /* We might still have some bits left which need to be zeroed. */
 408         if (cur_pos == 0 || first_rec + cur_pos - 1 < last_rec) {
 409                 if (d_stop != 0)
 410                         wz_count = last_rec - d_stop;
 411                 else if (wz_stop != 0)
 412                         wz_count = last_rec - wz_stop;
 413                 else
 414                         wz_count = count;
 415
 416                 ccw[-1].flags |= CCW_FLAG_CC;
 417                 locate_record(ccw++, LO_data++, WRITE, cur_pos, wz_count);
 418
 419                 ccw[-1].flags |= CCW_FLAG_CC;
 420                 ccw_write_zero(ccw++, wz_count * blksize);
 421         }
 422
 423         if (blk_noretry_request(req) ||
 424             block->base->features & DASD_FEATURE_FAILFAST)
 425                 set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
 426
 427         cqr->startdev = memdev;
 428         cqr->memdev = memdev;
 429         cqr->block = block;
 430         cqr->expires = memdev->default_expires * HZ;    /* default 5 minutes */
 431         cqr->retries = memdev->default_retries;
 432         cqr->buildclk = get_tod_clock();
 433         cqr->status = DASD_CQR_FILLED;
 434
 435         return cqr;
 436 }
 437
 438 static struct dasd_ccw_req *dasd_fba_build_cp_regular(
 439                                                 struct dasd_device *memdev,
 440                                                 struct dasd_block *block,
 441                                                 struct request *req)
 442 {
 443         struct dasd_fba_private *private = block->base->private;
 444         unsigned long *idaws;
 445         struct LO_fba_data *LO_data;
 446         struct dasd_ccw_req *cqr;
 447         struct ccw1 *ccw;
 448         struct req_iterator iter;
 449         struct bio_vec bv;
 450         char *dst;
 451         int count, cidaw, cplength, datasize;
 452         sector_t recid, first_rec, last_rec;
 453         unsigned int blksize, off;
 454         unsigned char cmd;
 455
 456         if (rq_data_dir(req) == READ) {
 457                 cmd = DASD_FBA_CCW_READ;
 458         } else if (rq_data_dir(req) == WRITE) {
 459                 cmd = DASD_FBA_CCW_WRITE;
 460         } else
 461                 return ERR_PTR(-EINVAL);
 462         blksize = block->bp_block;
 463         /* Calculate record id of first and last block. */
 464         first_rec = blk_rq_pos(req) >> block->s2b_shift;
 465         last_rec =
 466                 (blk_rq_pos(req) + blk_rq_sectors(req) - 1) >> block->s2b_shift;
 467         /* Check struct bio and count the number of blocks for the request. */
 468         count = 0;
 469         cidaw = 0;
 470         rq_for_each_segment(bv, req, iter) {
 471                 if (bv.bv_len & (blksize - 1))
 472                         /* Fba can only do full blocks. */
 473                         return ERR_PTR(-EINVAL);
 474                 count += bv.bv_len >> (block->s2b_shift + 9);
 475                 if (idal_is_needed (page_address(bv.bv_page), bv.bv_len))
 476                         cidaw += bv.bv_len / blksize;
 477         }
 478         /* Paranoia. */
 479         if (count != last_rec - first_rec + 1)
 480                 return ERR_PTR(-EINVAL);
 481         /* 1x define extent + 1x locate record + number of blocks */
 482         cplength = 2 + count;
 483         /* 1x define extent + 1x locate record */
 484         datasize = sizeof(struct DE_fba_data) + sizeof(struct LO_fba_data) +
 485                 cidaw * sizeof(unsigned long);
 486         /*
 487          * Find out number of additional locate record ccws if the device
 488          * can't do data chaining.
 489          */
 490         if (private->rdc_data.mode.bits.data_chain == 0) {
 491                 cplength += count - 1;
 492                 datasize += (count - 1)*sizeof(struct LO_fba_data);
 493         }
 494         /* Allocate the ccw request. */
 495         cqr = dasd_smalloc_request(DASD_FBA_MAGIC, cplength, datasize, memdev,
 496                                    blk_mq_rq_to_pdu(req));
 497         if (IS_ERR(cqr))
 498                 return cqr;
 499         ccw = cqr->cpaddr;
 500         /* First ccw is define extent. */
 501         define_extent(ccw++, cqr->data, rq_data_dir(req),
 502                       block->bp_block, blk_rq_pos(req), blk_rq_sectors(req));
 503         /* Build locate_record + read/write ccws. */
 504         idaws = (unsigned long *) (cqr->data + sizeof(struct DE_fba_data));
 505         LO_data = (struct LO_fba_data *) (idaws + cidaw);
 506         /* Locate record for all blocks for smart devices. */
 507         if (private->rdc_data.mode.bits.data_chain != 0) {
 508                 ccw[-1].flags |= CCW_FLAG_CC;
 509                 locate_record(ccw++, LO_data++, rq_data_dir(req), 0, count);
 510         }
 511         recid = first_rec;
 512         rq_for_each_segment(bv, req, iter) {
 513                 dst = page_address(bv.bv_page) + bv.bv_offset;
 514                 if (dasd_page_cache) {
 515                         char *copy = kmem_cache_alloc(dasd_page_cache,
 516                                                       GFP_DMA | __GFP_NOWARN);
 517                         if (copy && rq_data_dir(req) == WRITE)
 518                                 memcpy(copy + bv.bv_offset, dst, bv.bv_len);
 519                         if (copy)
 520                                 dst = copy + bv.bv_offset;
 521                 }
 522                 for (off = 0; off < bv.bv_len; off += blksize) {
 523                         /* Locate record for stupid devices. */
 524                         if (private->rdc_data.mode.bits.data_chain == 0) {
 525                                 ccw[-1].flags |= CCW_FLAG_CC;
 526                                 locate_record(ccw, LO_data++,
 527                                               rq_data_dir(req),
 528                                               recid - first_rec, 1);
 529                                 ccw->flags = CCW_FLAG_CC;
 530                                 ccw++;
 531                         } else {
 532                                 if (recid > first_rec)
 533                                         ccw[-1].flags |= CCW_FLAG_DC;
 534                                 else
 535                                         ccw[-1].flags |= CCW_FLAG_CC;
 536                         }
 537                         ccw->cmd_code = cmd;
 538                         ccw->count = block->bp_block;
 539                         if (idal_is_needed(dst, blksize)) {
 540                                 ccw->cda = (__u32)(addr_t) idaws;
 541                                 ccw->flags = CCW_FLAG_IDA;
 542                                 idaws = idal_create_words(idaws, dst, blksize);
 543                         } else {
 544                                 ccw->cda = (__u32)(addr_t) dst;
 545                                 ccw->flags = 0;
 546                         }
 547                         ccw++;
 548                         dst += blksize;
 549                         recid++;
 550                 }
 551         }
 552         if (blk_noretry_request(req) ||
 553             block->base->features & DASD_FEATURE_FAILFAST)
 554                 set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
 555         cqr->startdev = memdev;
 556         cqr->memdev = memdev;
 557         cqr->block = block;
 558         cqr->expires = memdev->default_expires * HZ;    /* default 5 minutes */
 559         cqr->retries = memdev->default_retries;
 560         cqr->buildclk = get_tod_clock();
 561         cqr->status = DASD_CQR_FILLED;
 562         return cqr;
 563 }
 564
 565 static struct dasd_ccw_req *dasd_fba_build_cp(struct dasd_device *memdev,
 566                                               struct dasd_block *block,
 567                                               struct request *req)
 568 {
 569         if (req_op(req) == REQ_OP_DISCARD || req_op(req) == REQ_OP_WRITE_ZEROES)
 570                 return dasd_fba_build_cp_discard(memdev, block, req);
 571         else
 572                 return dasd_fba_build_cp_regular(memdev, block, req);
 573 }
 574
 575 static int
 576 dasd_fba_free_cp(struct dasd_ccw_req *cqr, struct request *req)
 577 {
 578         struct dasd_fba_private *private = cqr->block->base->private;
 579         struct ccw1 *ccw;
 580         struct req_iterator iter;
 581         struct bio_vec bv;
 582         char *dst, *cda;
 583         unsigned int blksize, off;
 584         int status;
 585
 586         if (!dasd_page_cache)
 587                 goto out;
 588         blksize = cqr->block->bp_block;
 589         ccw = cqr->cpaddr;
 590         /* Skip over define extent & locate record. */
 591         ccw++;
 592         if (private->rdc_data.mode.bits.data_chain != 0)
 593                 ccw++;
 594         rq_for_each_segment(bv, req, iter) {
 595                 dst = page_address(bv.bv_page) + bv.bv_offset;
 596                 for (off = 0; off < bv.bv_len; off += blksize) {
 597                         /* Skip locate record. */
 598                         if (private->rdc_data.mode.bits.data_chain == 0)
 599                                 ccw++;
 600                         if (dst) {
 601                                 if (ccw->flags & CCW_FLAG_IDA)
 602                                         cda = *((char **)((addr_t) ccw->cda));
 603                                 else
 604                                         cda = (char *)((addr_t) ccw->cda);
 605                                 if (dst != cda) {
 606                                         if (rq_data_dir(req) == READ)
 607                                                 memcpy(dst, cda, bv.bv_len);
 608                                         kmem_cache_free(dasd_page_cache,
 609                                             (void *)((addr_t)cda & PAGE_MASK));
 610                                 }
 611                                 dst = NULL;
 612                         }
 613                         ccw++;
 614                 }
 615         }
 616 out:
 617         status = cqr->status == DASD_CQR_DONE;
 618         dasd_sfree_request(cqr, cqr->memdev);
 619         return status;
 620 }
 621
 622 static void dasd_fba_handle_terminated_request(struct dasd_ccw_req *cqr)
 623 {
 624         if (cqr->retries < 0)
 625                 cqr->status = DASD_CQR_FAILED;
 626         else
 627                 cqr->status = DASD_CQR_FILLED;
 628 };
 629
 630 static int
 631 dasd_fba_fill_info(struct dasd_device * device,
 632                    struct dasd_information2_t * info)
 633 {
 634         struct dasd_fba_private *private = device->private;
 635
 636         info->label_block = 1;
 637         info->FBA_layout = 1;
 638         info->format = DASD_FORMAT_LDL;
 639         info->characteristics_size = sizeof(private->rdc_data);
 640         memcpy(info->characteristics, &private->rdc_data,
 641                sizeof(private->rdc_data));
 642         info->confdata_size = 0;
 643         return 0;
 644 }
 645
 646 static void
 647 dasd_fba_dump_sense_dbf(struct dasd_device *device, struct irb *irb,
 648                         char *reason)
 649 {
 650         u64 *sense;
 651
 652         sense = (u64 *) dasd_get_sense(irb);
 653         if (sense) {
 654                 DBF_DEV_EVENT(DBF_EMERG, device,
 655                               "%s: %s %02x%02x%02x %016llx %016llx %016llx "
 656                               "%016llx", reason,
 657                               scsw_is_tm(&irb->scsw) ? "t" : "c",
 658                               scsw_cc(&irb->scsw), scsw_cstat(&irb->scsw),
 659                               scsw_dstat(&irb->scsw), sense[0], sense[1],
 660                               sense[2], sense[3]);
 661         } else {
 662                 DBF_DEV_EVENT(DBF_EMERG, device, "%s",
 663                               "SORRY - NO VALID SENSE AVAILABLE\n");
 664         }
 665 }
 666
 667
 668 static void
 669 dasd_fba_dump_sense(struct dasd_device *device, struct dasd_ccw_req * req,
 670                     struct irb *irb)
 671 {
 672         char *page;
 673         struct ccw1 *act, *end, *last;
 674         int len, sl, sct, count;
 675
 676         page = (char *) get_zeroed_page(GFP_ATOMIC);
 677         if (page == NULL) {
 678                 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
 679                             "No memory to dump sense data");
 680                 return;
 681         }
 682         len = sprintf(page, PRINTK_HEADER
 683                       " I/O status report for device %s:\n",
 684                       dev_name(&device->cdev->dev));
 685         len += sprintf(page + len, PRINTK_HEADER
 686                        " in req: %p CS: 0x%02X DS: 0x%02X\n", req,
 687                        irb->scsw.cmd.cstat, irb->scsw.cmd.dstat);
 688         len += sprintf(page + len, PRINTK_HEADER
 689                        " device %s: Failing CCW: %p\n",
 690                        dev_name(&device->cdev->dev),
 691                        (void *) (addr_t) irb->scsw.cmd.cpa);
 692         if (irb->esw.esw0.erw.cons) {
 693                 for (sl = 0; sl < 4; sl++) {
 694                         len += sprintf(page + len, PRINTK_HEADER
 695                                        " Sense(hex) %2d-%2d:",
 696                                        (8 * sl), ((8 * sl) + 7));
 697
 698                         for (sct = 0; sct < 8; sct++) {
 699                                 len += sprintf(page + len, " %02x",
 700                                                irb->ecw[8 * sl + sct]);
 701                         }
 702                         len += sprintf(page + len, "\n");
 703                 }
 704         } else {
 705                 len += sprintf(page + len, PRINTK_HEADER
 706                                " SORRY - NO VALID SENSE AVAILABLE\n");
 707         }
 708         printk(KERN_ERR "%s", page);
 709
 710         /* dump the Channel Program */
 711         /* print first CCWs (maximum 8) */
 712         act = req->cpaddr;
 713         for (last = act; last->flags & (CCW_FLAG_CC | CCW_FLAG_DC); last++);
 714         end = min(act + 8, last);
 715         len = sprintf(page, PRINTK_HEADER " Related CP in req: %p\n", req);
 716         while (act <= end) {
 717                 len += sprintf(page + len, PRINTK_HEADER
 718                                " CCW %p: %08X %08X DAT:",
 719                                act, ((int *) act)[0], ((int *) act)[1]);
 720                 for (count = 0; count < 32 && count < act->count;
 721                      count += sizeof(int))
 722                         len += sprintf(page + len, " %08X",
 723                                        ((int *) (addr_t) act->cda)
 724                                        [(count>>2)]);
 725                 len += sprintf(page + len, "\n");
 726                 act++;
 727         }
 728         printk(KERN_ERR "%s", page);
 729
 730
 731         /* print failing CCW area */
 732         len = 0;
 733         if (act <  ((struct ccw1 *)(addr_t) irb->scsw.cmd.cpa) - 2) {
 734                 act = ((struct ccw1 *)(addr_t) irb->scsw.cmd.cpa) - 2;
 735                 len += sprintf(page + len, PRINTK_HEADER "......\n");
 736         }
 737         end = min((struct ccw1 *)(addr_t) irb->scsw.cmd.cpa + 2, last);
 738         while (act <= end) {
 739                 len += sprintf(page + len, PRINTK_HEADER
 740                                " CCW %p: %08X %08X DAT:",
 741                                act, ((int *) act)[0], ((int *) act)[1]);
 742                 for (count = 0; count < 32 && count < act->count;
 743                      count += sizeof(int))
 744                         len += sprintf(page + len, " %08X",
 745                                        ((int *) (addr_t) act->cda)
 746                                        [(count>>2)]);
 747                 len += sprintf(page + len, "\n");
 748                 act++;
 749         }
 750
 751         /* print last CCWs */
 752         if (act <  last - 2) {
 753                 act = last - 2;
 754                 len += sprintf(page + len, PRINTK_HEADER "......\n");
 755         }
 756         while (act <= last) {
 757                 len += sprintf(page + len, PRINTK_HEADER
 758                                " CCW %p: %08X %08X DAT:",
 759                                act, ((int *) act)[0], ((int *) act)[1]);
 760                 for (count = 0; count < 32 && count < act->count;
 761                      count += sizeof(int))
 762                         len += sprintf(page + len, " %08X",
 763                                        ((int *) (addr_t) act->cda)
 764                                        [(count>>2)]);
 765                 len += sprintf(page + len, "\n");
 766                 act++;
 767         }
 768         if (len > 0)
 769                 printk(KERN_ERR "%s", page);
 770         free_page((unsigned long) page);
 771 }
 772
 773 /*
 774  * max_blocks is dependent on the amount of storage that is available
 775  * in the static io buffer for each device. Currently each device has
 776  * 8192 bytes (=2 pages). For 64 bit one dasd_mchunkt_t structure has
 777  * 24 bytes, the struct dasd_ccw_req has 136 bytes and each block can use
 778  * up to 16 bytes (8 for the ccw and 8 for the idal pointer). In
 779  * addition we have one define extent ccw + 16 bytes of data and a
 780  * locate record ccw for each block (stupid devices!) + 16 bytes of data.
 781  * That makes:
 782  * (8192 - 24 - 136 - 8 - 16) / 40 = 200.2 blocks at maximum.
 783  * We want to fit two into the available memory so that we can immediately
 784  * start the next request if one finishes off. That makes 100.1 blocks
 785  * for one request. Give a little safety and the result is 96.
 786  */
 787 static struct dasd_discipline dasd_fba_discipline = {
 788         .owner = THIS_MODULE,
 789         .name = "FBA ",
 790         .ebcname = "FBA ",
 791         .max_blocks = 96,
 792         .check_device = dasd_fba_check_characteristics,
 793         .do_analysis = dasd_fba_do_analysis,
 794         .verify_path = dasd_generic_verify_path,
 795         .fill_geometry = dasd_fba_fill_geometry,
 796         .start_IO = dasd_start_IO,
 797         .term_IO = dasd_term_IO,
 798         .handle_terminated_request = dasd_fba_handle_terminated_request,
 799         .erp_action = dasd_fba_erp_action,
 800         .erp_postaction = dasd_fba_erp_postaction,
 801         .check_for_device_change = dasd_fba_check_for_device_change,
 802         .build_cp = dasd_fba_build_cp,
 803         .free_cp = dasd_fba_free_cp,
 804         .dump_sense = dasd_fba_dump_sense,
 805         .dump_sense_dbf = dasd_fba_dump_sense_dbf,
 806         .fill_info = dasd_fba_fill_info,
 807 };
 808
 809 static int __init
 810 dasd_fba_init(void)
 811 {
 812         int ret;
 813
 814         ASCEBC(dasd_fba_discipline.ebcname, 4);
 815
 816         dasd_fba_zero_page = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
 817         if (!dasd_fba_zero_page)
 818                 return -ENOMEM;
 819
 820         ret = ccw_driver_register(&dasd_fba_driver);
 821         if (!ret)
 822                 wait_for_device_probe();
 823
 824         return ret;
 825 }
 826
 827 static void __exit
 828 dasd_fba_cleanup(void)
 829 {
 830         ccw_driver_unregister(&dasd_fba_driver);
 831         free_page((unsigned long)dasd_fba_zero_page);
 832 }
 833
 834 module_init(dasd_fba_init);
 835 module_exit(dasd_fba_cleanup);