drivers/s390/block/dasd_diag.c

   1 /*
   2  * File...........: linux/drivers/s390/block/dasd_diag.c
   3  * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
   4  * Based on.......: linux/drivers/s390/block/mdisk.c
   5  * ...............: by Hartmunt Penner <hpenner@de.ibm.com>
   6  * Bugreports.to..: <Linux390@de.ibm.com>
   7  * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999,2000
   8  *
   9  * $Revision: 1.42 $
  10  */
  11
  12 #include <linux/config.h>
  13 #include <linux/stddef.h>
  14 #include <linux/kernel.h>
  15 #include <linux/slab.h>
  16 #include <linux/hdreg.h>        /* HDIO_GETGEO                      */
  17 #include <linux/bio.h>
  18 #include <linux/module.h>
  19 #include <linux/init.h>
  20
  21 #include <asm/dasd.h>
  22 #include <asm/debug.h>
  23 #include <asm/ebcdic.h>
  24 #include <asm/io.h>
  25 #include <asm/s390_ext.h>
  26 #include <asm/todclk.h>
  27
  28 #include "dasd_int.h"
  29 #include "dasd_diag.h"
  30
  31 #ifdef PRINTK_HEADER
  32 #undef PRINTK_HEADER
  33 #endif                          /* PRINTK_HEADER */
  34 #define PRINTK_HEADER "dasd(diag):"
  35
  36 MODULE_LICENSE("GPL");
  37
  38 struct dasd_discipline dasd_diag_discipline;
  39
  40 struct dasd_diag_private {
  41         struct dasd_diag_characteristics rdc_data;
  42         struct dasd_diag_rw_io iob;
  43         struct dasd_diag_init_io iib;
  44         unsigned int pt_block;
  45 };
  46
  47 struct dasd_diag_req {
  48         int block_count;
  49         struct dasd_diag_bio bio[0];
  50 };
  51
  52 static __inline__ int
  53 dia250(void *iob, int cmd)
  54 {
  55         int rc;
  56
  57         __asm__ __volatile__("    lhi   %0,3\n"
  58                              "    lr    0,%2\n"
  59                              "    diag  0,%1,0x250\n"
  60                              "0:  ipm   %0\n"
  61                              "    srl   %0,28\n"
  62                              "    or    %0,1\n"
  63                              "1:\n"
  64 #ifndef CONFIG_ARCH_S390X
  65                              ".section __ex_table,\"a\"\n"
  66                              "    .align 4\n"
  67                              "    .long 0b,1b\n"
  68                              ".previous\n"
  69 #else
  70                              ".section __ex_table,\"a\"\n"
  71                              "    .align 8\n"
  72                              "    .quad  0b,1b\n"
  73                              ".previous\n"
  74 #endif
  75                              : "=&d" (rc)
  76                              : "d" (cmd), "d" ((void *) __pa(iob))
  77                              : "0", "1", "cc");
  78         return rc;
  79 }
  80
  81 static __inline__ int
  82 mdsk_init_io(struct dasd_device * device, int blocksize, int offset, int size)
  83 {
  84         struct dasd_diag_private *private;
  85         struct dasd_diag_init_io *iib;
  86         int rc;
  87
  88         private = (struct dasd_diag_private *) device->private;
  89         iib = &private->iib;
  90         memset(iib, 0, sizeof (struct dasd_diag_init_io));
  91
  92         iib->dev_nr = _ccw_device_get_device_number(device->cdev);
  93         iib->block_size = blocksize;
  94         iib->offset = offset;
  95         iib->start_block = 0;
  96         iib->end_block = size;
  97
  98         rc = dia250(iib, INIT_BIO);
  99
 100         return rc & 3;
 101 }
 102
 103 static __inline__ int
 104 mdsk_term_io(struct dasd_device * device)
 105 {
 106         struct dasd_diag_private *private;
 107         struct dasd_diag_init_io *iib;
 108         int rc;
 109
 110         private = (struct dasd_diag_private *) device->private;
 111         iib = &private->iib;
 112         memset(iib, 0, sizeof (struct dasd_diag_init_io));
 113         iib->dev_nr = _ccw_device_get_device_number(device->cdev);
 114         rc = dia250(iib, TERM_BIO);
 115         return rc & 3;
 116 }
 117
 118 static int
 119 dasd_start_diag(struct dasd_ccw_req * cqr)
 120 {
 121         struct dasd_device *device;
 122         struct dasd_diag_private *private;
 123         struct dasd_diag_req *dreq;
 124         int rc;
 125
 126         device = cqr->device;
 127         private = (struct dasd_diag_private *) device->private;
 128         dreq = (struct dasd_diag_req *) cqr->data;
 129
 130         private->iob.dev_nr = _ccw_device_get_device_number(device->cdev);
 131         private->iob.key = 0;
 132         private->iob.flags = 2; /* do asynchronous io */
 133         private->iob.block_count = dreq->block_count;
 134         private->iob.interrupt_params = (u32)(addr_t) cqr;
 135         private->iob.bio_list = __pa(dreq->bio);
 136
 137         cqr->startclk = get_clock();
 138
 139         rc = dia250(&private->iob, RW_BIO);
 140         if (rc > 8) {
 141                 DEV_MESSAGE(KERN_WARNING, device, "dia250 returned CC %d", rc);
 142                 cqr->status = DASD_CQR_ERROR;
 143         } else if (rc == 0) {
 144                 cqr->status = DASD_CQR_DONE;
 145                 dasd_schedule_bh(device);
 146         } else {
 147                 cqr->status = DASD_CQR_IN_IO;
 148                 rc = 0;
 149         }
 150         return rc;
 151 }
 152
 153 static void
 154 dasd_ext_handler(struct pt_regs *regs, __u16 code)
 155 {
 156         struct dasd_ccw_req *cqr, *next;
 157         struct dasd_device *device;
 158         unsigned long long expires;
 159         unsigned long flags;
 160         char status;
 161         int ip;
 162
 163         /*
 164          * Get the external interruption subcode. VM stores
 165          * this in the 'cpu address' field associated with
 166          * the external interrupt. For diag 250 the subcode
 167          * needs to be 3.
 168          */
 169         if ((S390_lowcore.cpu_addr & 0xff00) != 0x0300)
 170                 return;
 171         status = *((char *) &S390_lowcore.ext_params + 5);
 172         ip = S390_lowcore.ext_params;
 173
 174         if (!ip) {              /* no intparm: unsolicited interrupt */
 175                 MESSAGE(KERN_DEBUG, "%s", "caught unsolicited interrupt");
 176                 return;
 177         }
 178         cqr = (struct dasd_ccw_req *)(addr_t) ip;
 179         device = (struct dasd_device *) cqr->device;
 180         if (strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
 181                 DEV_MESSAGE(KERN_WARNING, device,
 182                             " magic number of dasd_ccw_req 0x%08X doesn't"
 183                             " match discipline 0x%08X",
 184                             cqr->magic, *(int *) (&device->discipline->name));
 185                 return;
 186         }
 187
 188         /* get irq lock to modify request queue */
 189         spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
 190
 191         cqr->stopclk = get_clock();
 192
 193         expires = 0;
 194         if (status == 0) {
 195                 cqr->status = DASD_CQR_DONE;
 196                 /* Start first request on queue if possible -> fast_io. */
 197                 if (!list_empty(&device->ccw_queue)) {
 198                         next = list_entry(device->ccw_queue.next,
 199                                           struct dasd_ccw_req, list);
 200                         if (next->status == DASD_CQR_QUEUED) {
 201                                 if (dasd_start_diag(next) == 0)
 202                                         expires = next->expires;
 203                                 else
 204                                         DEV_MESSAGE(KERN_WARNING, device, "%s",
 205                                                     "Interrupt fastpath "
 206                                                     "failed!");
 207                         }
 208                 }
 209         } else
 210                 cqr->status = DASD_CQR_FAILED;
 211
 212         if (expires != 0)
 213                 dasd_set_timer(device, expires);
 214         else
 215                 dasd_clear_timer(device);
 216         dasd_schedule_bh(device);
 217
 218         spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
 219 }
 220
 221 static int
 222 dasd_diag_check_device(struct dasd_device *device)
 223 {
 224         struct dasd_diag_private *private;
 225         struct dasd_diag_characteristics *rdc_data;
 226         struct dasd_diag_bio bio;
 227         long *label;
 228         int sb, bsize;
 229         int rc;
 230
 231         private = (struct dasd_diag_private *) device->private;
 232         if (private == NULL) {
 233                 private = kmalloc(sizeof(struct dasd_diag_private),GFP_KERNEL);
 234                 if (private == NULL) {
 235                         DEV_MESSAGE(KERN_WARNING, device, "%s",
 236                                 "memory allocation failed for private data");
 237                         return -ENOMEM;
 238                 }
 239                 device->private = (void *) private;
 240         }
 241         /* Read Device Characteristics */
 242         rdc_data = (void *) &(private->rdc_data);
 243         rdc_data->dev_nr = _ccw_device_get_device_number(device->cdev);
 244         rdc_data->rdc_len = sizeof (struct dasd_diag_characteristics);
 245
 246         rc = diag210((struct diag210 *) rdc_data);
 247         if (rc)
 248                 return -ENOTSUPP;
 249
 250         /* Figure out position of label block */
 251         switch (private->rdc_data.vdev_class) {
 252         case DEV_CLASS_FBA:
 253                 private->pt_block = 1;
 254                 break;
 255         case DEV_CLASS_ECKD:
 256                 private->pt_block = 2;
 257                 break;
 258         default:
 259                 return -ENOTSUPP;
 260         }
 261
 262         DBF_DEV_EVENT(DBF_INFO, device,
 263                       "%04X: %04X on real %04X/%02X",
 264                       rdc_data->dev_nr,
 265                       rdc_data->vdev_type,
 266                       rdc_data->rdev_type, rdc_data->rdev_model);
 267
 268         /* terminate all outstanding operations */
 269         mdsk_term_io(device);
 270
 271         /* figure out blocksize of device */
 272         label = (long *) get_zeroed_page(GFP_KERNEL);
 273         if (label == NULL)  {
 274                 DEV_MESSAGE(KERN_WARNING, device, "%s",
 275                             "No memory to allocate initialization request");
 276                 return -ENOMEM;
 277         }
 278         /* try all sizes - needed for ECKD devices */
 279         for (bsize = 512; bsize <= PAGE_SIZE; bsize <<= 1) {
 280                 mdsk_init_io(device, bsize, 0, 64);
 281                 memset(&bio, 0, sizeof (struct dasd_diag_bio));
 282                 bio.type = MDSK_READ_REQ;
 283                 bio.block_number = private->pt_block + 1;
 284                 bio.buffer = __pa(label);
 285                 memset(&private->iob, 0, sizeof (struct dasd_diag_rw_io));
 286                 private->iob.dev_nr = rdc_data->dev_nr;
 287                 private->iob.key = 0;
 288                 private->iob.flags = 0; /* do synchronous io */
 289                 private->iob.block_count = 1;
 290                 private->iob.interrupt_params = 0;
 291                 private->iob.bio_list = __pa(&bio);
 292                 if (dia250(&private->iob, RW_BIO) == 0)
 293                         break;
 294                 mdsk_term_io(device);
 295         }
 296         if (bsize <= PAGE_SIZE && label[0] == 0xc3d4e2f1) {
 297                 /* get formatted blocksize from label block */
 298                 bsize = (int) label[3];
 299                 device->blocks = label[7];
 300                 device->bp_block = bsize;
 301                 device->s2b_shift = 0;  /* bits to shift 512 to get a block */
 302                 for (sb = 512; sb < bsize; sb = sb << 1)
 303                         device->s2b_shift++;
 304
 305                 DEV_MESSAGE(KERN_INFO, device,
 306                             "capacity (%dkB blks): %ldkB",
 307                             (device->bp_block >> 10),
 308                             (device->blocks << device->s2b_shift) >> 1);
 309                 rc = 0;
 310         } else {
 311                 if (bsize > PAGE_SIZE)
 312                         DEV_MESSAGE(KERN_WARNING, device, "%s",
 313                                     "DIAG access failed");
 314                 else
 315                         DEV_MESSAGE(KERN_WARNING, device, "%s",
 316                                     "volume is not CMS formatted");
 317                 rc = -EMEDIUMTYPE;
 318         }
 319         free_page((long) label);
 320         return rc;
 321 }
 322
 323 static int
 324 dasd_diag_fill_geometry(struct dasd_device *device, struct hd_geometry *geo)
 325 {
 326         if (dasd_check_blocksize(device->bp_block) != 0)
 327                 return -EINVAL;
 328         geo->cylinders = (device->blocks << device->s2b_shift) >> 10;
 329         geo->heads = 16;
 330         geo->sectors = 128 >> device->s2b_shift;
 331         return 0;
 332 }
 333
 334 static dasd_era_t
 335 dasd_diag_examine_error(struct dasd_ccw_req * cqr, struct irb * stat)
 336 {
 337         return dasd_era_fatal;
 338 }
 339
 340 static dasd_erp_fn_t
 341 dasd_diag_erp_action(struct dasd_ccw_req * cqr)
 342 {
 343         return dasd_default_erp_action;
 344 }
 345
 346 static dasd_erp_fn_t
 347 dasd_diag_erp_postaction(struct dasd_ccw_req * cqr)
 348 {
 349         return dasd_default_erp_postaction;
 350 }
 351
 352 static struct dasd_ccw_req *
 353 dasd_diag_build_cp(struct dasd_device * device, struct request *req)
 354 {
 355         struct dasd_ccw_req *cqr;
 356         struct dasd_diag_req *dreq;
 357         struct dasd_diag_bio *dbio;
 358         struct bio *bio;
 359         struct bio_vec *bv;
 360         char *dst;
 361         int count, datasize;
 362         sector_t recid, first_rec, last_rec;
 363         unsigned blksize, off;
 364         unsigned char rw_cmd;
 365         int i;
 366
 367         if (rq_data_dir(req) == READ)
 368                 rw_cmd = MDSK_READ_REQ;
 369         else if (rq_data_dir(req) == WRITE)
 370                 rw_cmd = MDSK_WRITE_REQ;
 371         else
 372                 return ERR_PTR(-EINVAL);
 373         blksize = device->bp_block;
 374         /* Calculate record id of first and last block. */
 375         first_rec = req->sector >> device->s2b_shift;
 376         last_rec = (req->sector + req->nr_sectors - 1) >> device->s2b_shift;
 377         /* Check struct bio and count the number of blocks for the request. */
 378         count = 0;
 379         rq_for_each_bio(bio, req) {
 380                 bio_for_each_segment(bv, bio, i) {
 381                         if (bv->bv_len & (blksize - 1))
 382                                 /* Fba can only do full blocks. */
 383                                 return ERR_PTR(-EINVAL);
 384                         count += bv->bv_len >> (device->s2b_shift + 9);
 385                 }
 386         }
 387         /* Paranoia. */
 388         if (count != last_rec - first_rec + 1)
 389                 return ERR_PTR(-EINVAL);
 390         /* Build the request */
 391         datasize = sizeof(struct dasd_diag_req) +
 392                 count*sizeof(struct dasd_diag_bio);
 393         cqr = dasd_smalloc_request(dasd_diag_discipline.name, 0,
 394                                    datasize, device);
 395         if (IS_ERR(cqr))
 396                 return cqr;
 397
 398         dreq = (struct dasd_diag_req *) cqr->data;
 399         dreq->block_count = count;
 400         dbio = dreq->bio;
 401         recid = first_rec;
 402         rq_for_each_bio(bio, req) {
 403                 bio_for_each_segment(bv, bio, i) {
 404                         dst = page_address(bv->bv_page) + bv->bv_offset;
 405                         for (off = 0; off < bv->bv_len; off += blksize) {
 406                                 memset(dbio, 0, sizeof (struct dasd_diag_bio));
 407                                 dbio->type = rw_cmd;
 408                                 dbio->block_number = recid + 1;
 409                                 dbio->buffer = __pa(dst);
 410                                 dbio++;
 411                                 dst += blksize;
 412                                 recid++;
 413                         }
 414                 }
 415         }
 416         cqr->buildclk = get_clock();
 417         cqr->device = device;
 418         cqr->expires = 50 * HZ; /* 50 seconds */
 419         cqr->status = DASD_CQR_FILLED;
 420         return cqr;
 421 }
 422
 423 static int
 424 dasd_diag_free_cp(struct dasd_ccw_req *cqr, struct request *req)
 425 {
 426         int status;
 427
 428         status = cqr->status == DASD_CQR_DONE;
 429         dasd_sfree_request(cqr, cqr->device);
 430         return status;
 431 }
 432
 433 static int
 434 dasd_diag_fill_info(struct dasd_device * device,
 435                     struct dasd_information2_t * info)
 436 {
 437         struct dasd_diag_private *private;
 438
 439         private = (struct dasd_diag_private *) device->private;
 440         info->label_block = private->pt_block;
 441         info->FBA_layout = 1;
 442         info->format = DASD_FORMAT_LDL;
 443         info->characteristics_size = sizeof (struct dasd_diag_characteristics);
 444         memcpy(info->characteristics,
 445                &((struct dasd_diag_private *) device->private)->rdc_data,
 446                sizeof (struct dasd_diag_characteristics));
 447         info->confdata_size = 0;
 448         return 0;
 449 }
 450
 451 static void
 452 dasd_diag_dump_sense(struct dasd_device *device, struct dasd_ccw_req * req,
 453                      struct irb *stat)
 454 {
 455         DEV_MESSAGE(KERN_ERR, device, "%s",
 456                     "dump sense not available for DIAG data");
 457 }
 458
 459 /*
 460  * max_blocks is dependent on the amount of storage that is available
 461  * in the static io buffer for each device. Currently each device has
 462  * 8192 bytes (=2 pages). dasd diag is only relevant for 31 bit.
 463  * The struct dasd_ccw_req has 96 bytes, the struct dasd_diag_req has
 464  * 8 bytes and the struct dasd_diag_bio for each block has 16 bytes.
 465  * That makes:
 466  * (8192 - 96 - 8) / 16 = 505.5 blocks at maximum.
 467  * We want to fit two into the available memory so that we can immediately
 468  * start the next request if one finishes off. That makes 252.75 blocks
 469  * for one request. Give a little safety and the result is 240.
 470  */
 471 struct dasd_discipline dasd_diag_discipline = {
 472         .owner = THIS_MODULE,
 473         .name = "DIAG",
 474         .ebcname = "DIAG",
 475         .max_blocks = 240,
 476         .check_device = dasd_diag_check_device,
 477         .fill_geometry = dasd_diag_fill_geometry,
 478         .start_IO = dasd_start_diag,
 479         .examine_error = dasd_diag_examine_error,
 480         .erp_action = dasd_diag_erp_action,
 481         .erp_postaction = dasd_diag_erp_postaction,
 482         .build_cp = dasd_diag_build_cp,
 483         .free_cp = dasd_diag_free_cp,
 484         .dump_sense = dasd_diag_dump_sense,
 485         .fill_info = dasd_diag_fill_info,
 486 };
 487
 488 static int __init
 489 dasd_diag_init(void)
 490 {
 491         if (!MACHINE_IS_VM) {
 492                 MESSAGE_LOG(KERN_INFO,
 493                             "Machine is not VM: %s "
 494                             "discipline not initializing",
 495                             dasd_diag_discipline.name);
 496                 return -EINVAL;
 497         }
 498         ASCEBC(dasd_diag_discipline.ebcname, 4);
 499
 500         ctl_set_bit(0, 9);
 501         register_external_interrupt(0x2603, dasd_ext_handler);
 502         dasd_diag_discipline_pointer = &dasd_diag_discipline;
 503         return 0;
 504 }
 505
 506 static void __exit
 507 dasd_diag_cleanup(void)
 508 {
 509         if (!MACHINE_IS_VM) {
 510                 MESSAGE_LOG(KERN_INFO,
 511                             "Machine is not VM: %s "
 512                             "discipline not cleaned",
 513                             dasd_diag_discipline.name);
 514                 return;
 515         }
 516         unregister_external_interrupt(0x2603, dasd_ext_handler);
 517         ctl_clear_bit(0, 9);
 518         dasd_diag_discipline_pointer = NULL;
 519 }
 520
 521 module_init(dasd_diag_init);
 522 module_exit(dasd_diag_cleanup);
 523
 524 /*
 525  * Overrides for Emacs so that we follow Linus's tabbing style.
 526  * Emacs will notice this stuff at the end of the file and automatically
 527  * adjust the settings for this buffer only.  This must remain at the end
 528  * of the file.
 529  * ---------------------------------------------------------------------------
 530  * Local variables:
 531  * c-indent-level: 4
 532  * c-brace-imaginary-offset: 0
 533  * c-brace-offset: -4
 534  * c-argdecl-indent: 4
 535  * c-label-offset: -4
 536  * c-continued-statement-offset: 4
 537  * c-continued-brace-offset: 0
 538  * indent-tabs-mode: 1
 539  * tab-width: 8
 540  * End:
 541  */