drivers/s390/block/dasd_devmap.c

   1 /*
   2  * File...........: linux/drivers/s390/block/dasd_devmap.c
   3  * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
   4  *                  Horst Hummel <Horst.Hummel@de.ibm.com>
   5  *                  Carsten Otte <Cotte@de.ibm.com>
   6  *                  Martin Schwidefsky <schwidefsky@de.ibm.com>
   7  * Bugreports.to..: <Linux390@de.ibm.com>
   8  * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999-2001
   9  *
  10  * Device mapping and dasd= parameter parsing functions. All devmap
  11  * functions may not be called from interrupt context. In particular
  12  * dasd_get_device is a no-no from interrupt context.
  13  *
  14  */
  15
  16 #include <linux/ctype.h>
  17 #include <linux/init.h>
  18 #include <linux/module.h>
  19
  20 #include <asm/debug.h>
  21 #include <asm/uaccess.h>
  22 #include <asm/ipl.h>
  23
  24 /* This is ugly... */
  25 #define PRINTK_HEADER "dasd_devmap:"
  26 #define DASD_BUS_ID_SIZE 20
  27
  28 #include "dasd_int.h"
  29
  30 struct kmem_cache *dasd_page_cache;
  31 EXPORT_SYMBOL_GPL(dasd_page_cache);
  32
  33 /*
  34  * dasd_devmap_t is used to store the features and the relation
  35  * between device number and device index. To find a dasd_devmap_t
  36  * that corresponds to a device number of a device index each
  37  * dasd_devmap_t is added to two linked lists, one to search by
  38  * the device number and one to search by the device index. As
  39  * soon as big minor numbers are available the device index list
  40  * can be removed since the device number will then be identical
  41  * to the device index.
  42  */
  43 struct dasd_devmap {
  44         struct list_head list;
  45         char bus_id[DASD_BUS_ID_SIZE];
  46         unsigned int devindex;
  47         unsigned short features;
  48         struct dasd_device *device;
  49         struct dasd_uid uid;
  50 };
  51
  52 /*
  53  * Parameter parsing functions for dasd= parameter. The syntax is:
  54  *   <devno>            : (0x)?[0-9a-fA-F]+
  55  *   <busid>            : [0-0a-f]\.[0-9a-f]\.(0x)?[0-9a-fA-F]+
  56  *   <feature>          : ro
  57  *   <feature_list>     : \(<feature>(:<feature>)*\)
  58  *   <devno-range>      : <devno>(-<devno>)?<feature_list>?
  59  *   <busid-range>      : <busid>(-<busid>)?<feature_list>?
  60  *   <devices>          : <devno-range>|<busid-range>
  61  *   <dasd_module>      : dasd_diag_mod|dasd_eckd_mod|dasd_fba_mod
  62  *
  63  *   <dasd>             : autodetect|probeonly|<devices>(,<devices>)*
  64  */
  65
  66 int dasd_probeonly =  0;        /* is true, when probeonly mode is active */
  67 int dasd_autodetect = 0;        /* is true, when autodetection is active */
  68 int dasd_nopav = 0;             /* is true, when PAV is disabled */
  69 EXPORT_SYMBOL_GPL(dasd_nopav);
  70
  71 /*
  72  * char *dasd[] is intended to hold the ranges supplied by the dasd= statement
  73  * it is named 'dasd' to directly be filled by insmod with the comma separated
  74  * strings when running as a module.
  75  */
  76 static char *dasd[256];
  77 module_param_array(dasd, charp, NULL, 0);
  78
  79 /*
  80  * Single spinlock to protect devmap and servermap structures and lists.
  81  */
  82 static DEFINE_SPINLOCK(dasd_devmap_lock);
  83
  84 /*
  85  * Hash lists for devmap structures.
  86  */
  87 static struct list_head dasd_hashlists[256];
  88 int dasd_max_devindex;
  89
  90 static struct dasd_devmap *dasd_add_busid(const char *, int);
  91
  92 static inline int
  93 dasd_hash_busid(const char *bus_id)
  94 {
  95         int hash, i;
  96
  97         hash = 0;
  98         for (i = 0; (i < DASD_BUS_ID_SIZE) && *bus_id; i++, bus_id++)
  99                 hash += *bus_id;
 100         return hash & 0xff;
 101 }
 102
 103 #ifndef MODULE
 104 /*
 105  * The parameter parsing functions for builtin-drivers are called
 106  * before kmalloc works. Store the pointers to the parameters strings
 107  * into dasd[] for later processing.
 108  */
 109 static int __init
 110 dasd_call_setup(char *str)
 111 {
 112         static int count = 0;
 113
 114         if (count < 256)
 115                 dasd[count++] = str;
 116         return 1;
 117 }
 118
 119 __setup ("dasd=", dasd_call_setup);
 120 #endif  /* #ifndef MODULE */
 121
 122 #define DASD_IPLDEV     "ipldev"
 123
 124 /*
 125  * Read a device busid/devno from a string.
 126  */
 127 static int
 128 dasd_busid(char **str, int *id0, int *id1, int *devno)
 129 {
 130         int val, old_style;
 131
 132         /* Interpret ipldev busid */
 133         if (strncmp(DASD_IPLDEV, *str, strlen(DASD_IPLDEV)) == 0) {
 134                 if (ipl_info.type != IPL_TYPE_CCW) {
 135                         MESSAGE(KERN_ERR, "%s", "ipl device is not a ccw "
 136                                 "device");
 137                         return -EINVAL;
 138                 }
 139                 *id0 = 0;
 140                 *id1 = ipl_info.data.ccw.dev_id.ssid;
 141                 *devno = ipl_info.data.ccw.dev_id.devno;
 142                 *str += strlen(DASD_IPLDEV);
 143
 144                 return 0;
 145         }
 146         /* check for leading '0x' */
 147         old_style = 0;
 148         if ((*str)[0] == '0' && (*str)[1] == 'x') {
 149                 *str += 2;
 150                 old_style = 1;
 151         }
 152         if (!isxdigit((*str)[0]))       /* We require at least one hex digit */
 153                 return -EINVAL;
 154         val = simple_strtoul(*str, str, 16);
 155         if (old_style || (*str)[0] != '.') {
 156                 *id0 = *id1 = 0;
 157                 if (val < 0 || val > 0xffff)
 158                         return -EINVAL;
 159                 *devno = val;
 160                 return 0;
 161         }
 162         /* New style x.y.z busid */
 163         if (val < 0 || val > 0xff)
 164                 return -EINVAL;
 165         *id0 = val;
 166         (*str)++;
 167         if (!isxdigit((*str)[0]))       /* We require at least one hex digit */
 168                 return -EINVAL;
 169         val = simple_strtoul(*str, str, 16);
 170         if (val < 0 || val > 0xff || (*str)++[0] != '.')
 171                 return -EINVAL;
 172         *id1 = val;
 173         if (!isxdigit((*str)[0]))       /* We require at least one hex digit */
 174                 return -EINVAL;
 175         val = simple_strtoul(*str, str, 16);
 176         if (val < 0 || val > 0xffff)
 177                 return -EINVAL;
 178         *devno = val;
 179         return 0;
 180 }
 181
 182 /*
 183  * Read colon separated list of dasd features. Currently there is
 184  * only one: "ro" for read-only devices. The default feature set
 185  * is empty (value 0).
 186  */
 187 static int
 188 dasd_feature_list(char *str, char **endp)
 189 {
 190         int features, len, rc;
 191
 192         rc = 0;
 193         if (*str != '(') {
 194                 *endp = str;
 195                 return DASD_FEATURE_DEFAULT;
 196         }
 197         str++;
 198         features = 0;
 199
 200         while (1) {
 201                 for (len = 0;
 202                      str[len] && str[len] != ':' && str[len] != ')'; len++);
 203                 if (len == 2 && !strncmp(str, "ro", 2))
 204                         features |= DASD_FEATURE_READONLY;
 205                 else if (len == 4 && !strncmp(str, "diag", 4))
 206                         features |= DASD_FEATURE_USEDIAG;
 207                 else if (len == 6 && !strncmp(str, "erplog", 6))
 208                         features |= DASD_FEATURE_ERPLOG;
 209                 else if (len == 8 && !strncmp(str, "failfast", 8))
 210                         features |= DASD_FEATURE_FAILFAST;
 211                 else {
 212                         MESSAGE(KERN_WARNING,
 213                                 "unsupported feature: %*s, "
 214                                 "ignoring setting", len, str);
 215                         rc = -EINVAL;
 216                 }
 217                 str += len;
 218                 if (*str != ':')
 219                         break;
 220                 str++;
 221         }
 222         if (*str != ')') {
 223                 MESSAGE(KERN_WARNING, "%s",
 224                         "missing ')' in dasd parameter string\n");
 225                 rc = -EINVAL;
 226         } else
 227                 str++;
 228         *endp = str;
 229         if (rc != 0)
 230                 return rc;
 231         return features;
 232 }
 233
 234 /*
 235  * Try to match the first element on the comma separated parse string
 236  * with one of the known keywords. If a keyword is found, take the approprate
 237  * action and return a pointer to the residual string. If the first element
 238  * could not be matched to any keyword then return an error code.
 239  */
 240 static char *
 241 dasd_parse_keyword( char *parsestring ) {
 242
 243         char *nextcomma, *residual_str;
 244         int length;
 245
 246         nextcomma = strchr(parsestring,',');
 247         if (nextcomma) {
 248                 length = nextcomma - parsestring;
 249                 residual_str = nextcomma + 1;
 250         } else {
 251                 length = strlen(parsestring);
 252                 residual_str = parsestring + length;
 253         }
 254         if (strncmp("autodetect", parsestring, length) == 0) {
 255                 dasd_autodetect = 1;
 256                 MESSAGE (KERN_INFO, "%s",
 257                          "turning to autodetection mode");
 258                 return residual_str;
 259         }
 260         if (strncmp("probeonly", parsestring, length) == 0) {
 261                 dasd_probeonly = 1;
 262                 MESSAGE(KERN_INFO, "%s",
 263                         "turning to probeonly mode");
 264                 return residual_str;
 265         }
 266         if (strncmp("nopav", parsestring, length) == 0) {
 267                 if (MACHINE_IS_VM)
 268                         MESSAGE(KERN_INFO, "%s", "'nopav' not supported on VM");
 269                 else {
 270                         dasd_nopav = 1;
 271                         MESSAGE(KERN_INFO, "%s", "disable PAV mode");
 272                 }
 273                 return residual_str;
 274         }
 275         if (strncmp("fixedbuffers", parsestring, length) == 0) {
 276                 if (dasd_page_cache)
 277                         return residual_str;
 278                 dasd_page_cache =
 279                         kmem_cache_create("dasd_page_cache", PAGE_SIZE,
 280                                           PAGE_SIZE, SLAB_CACHE_DMA,
 281                                           NULL);
 282                 if (!dasd_page_cache)
 283                         MESSAGE(KERN_WARNING, "%s", "Failed to create slab, "
 284                                 "fixed buffer mode disabled.");
 285                 else
 286                         MESSAGE (KERN_INFO, "%s",
 287                                  "turning on fixed buffer mode");
 288                 return residual_str;
 289         }
 290         return ERR_PTR(-EINVAL);
 291 }
 292
 293 /*
 294  * Try to interprete the first element on the comma separated parse string
 295  * as a device number or a range of devices. If the interpretation is
 296  * successfull, create the matching dasd_devmap entries and return a pointer
 297  * to the residual string.
 298  * If interpretation fails or in case of an error, return an error code.
 299  */
 300 static char *
 301 dasd_parse_range( char *parsestring ) {
 302
 303         struct dasd_devmap *devmap;
 304         int from, from_id0, from_id1;
 305         int to, to_id0, to_id1;
 306         int features, rc;
 307         char bus_id[DASD_BUS_ID_SIZE+1], *str;
 308
 309         str = parsestring;
 310         rc = dasd_busid(&str, &from_id0, &from_id1, &from);
 311         if (rc == 0) {
 312                 to = from;
 313                 to_id0 = from_id0;
 314                 to_id1 = from_id1;
 315                 if (*str == '-') {
 316                         str++;
 317                         rc = dasd_busid(&str, &to_id0, &to_id1, &to);
 318                 }
 319         }
 320         if (rc == 0 &&
 321             (from_id0 != to_id0 || from_id1 != to_id1 || from > to))
 322                 rc = -EINVAL;
 323         if (rc) {
 324                 MESSAGE(KERN_ERR, "Invalid device range %s", parsestring);
 325                 return ERR_PTR(rc);
 326         }
 327         features = dasd_feature_list(str, &str);
 328         if (features < 0)
 329                 return ERR_PTR(-EINVAL);
 330         /* each device in dasd= parameter should be set initially online */
 331         features |= DASD_FEATURE_INITIAL_ONLINE;
 332         while (from <= to) {
 333                 sprintf(bus_id, "%01x.%01x.%04x",
 334                         from_id0, from_id1, from++);
 335                 devmap = dasd_add_busid(bus_id, features);
 336                 if (IS_ERR(devmap))
 337                         return (char *)devmap;
 338         }
 339         if (*str == ',')
 340                 return str + 1;
 341         if (*str == '\0')
 342                 return str;
 343         MESSAGE(KERN_WARNING,
 344                 "junk at end of dasd parameter string: %s\n", str);
 345         return ERR_PTR(-EINVAL);
 346 }
 347
 348 static char *
 349 dasd_parse_next_element( char *parsestring ) {
 350         char * residual_str;
 351         residual_str = dasd_parse_keyword(parsestring);
 352         if (!IS_ERR(residual_str))
 353                 return residual_str;
 354         residual_str = dasd_parse_range(parsestring);
 355         return residual_str;
 356 }
 357
 358 /*
 359  * Parse parameters stored in dasd[]
 360  * The 'dasd=...' parameter allows to specify a comma separated list of
 361  * keywords and device ranges. When the dasd driver is build into the kernel,
 362  * the complete list will be stored as one element of the dasd[] array.
 363  * When the dasd driver is build as a module, then the list is broken into
 364  * it's elements and each dasd[] entry contains one element.
 365  */
 366 int
 367 dasd_parse(void)
 368 {
 369         int rc, i;
 370         char *parsestring;
 371
 372         rc = 0;
 373         for (i = 0; i < 256; i++) {
 374                 if (dasd[i] == NULL)
 375                         break;
 376                 parsestring = dasd[i];
 377                 /* loop over the comma separated list in the parsestring */
 378                 while (*parsestring) {
 379                         parsestring = dasd_parse_next_element(parsestring);
 380                         if(IS_ERR(parsestring)) {
 381                                 rc = PTR_ERR(parsestring);
 382                                 break;
 383                         }
 384                 }
 385                 if (rc) {
 386                         DBF_EVENT(DBF_ALERT, "%s", "invalid range found");
 387                         break;
 388                 }
 389         }
 390         return rc;
 391 }
 392
 393 /*
 394  * Add a devmap for the device specified by busid. It is possible that
 395  * the devmap already exists (dasd= parameter). The order of the devices
 396  * added through this function will define the kdevs for the individual
 397  * devices.
 398  */
 399 static struct dasd_devmap *
 400 dasd_add_busid(const char *bus_id, int features)
 401 {
 402         struct dasd_devmap *devmap, *new, *tmp;
 403         int hash;
 404
 405         new = (struct dasd_devmap *)
 406                 kzalloc(sizeof(struct dasd_devmap), GFP_KERNEL);
 407         if (!new)
 408                 return ERR_PTR(-ENOMEM);
 409         spin_lock(&dasd_devmap_lock);
 410         devmap = NULL;
 411         hash = dasd_hash_busid(bus_id);
 412         list_for_each_entry(tmp, &dasd_hashlists[hash], list)
 413                 if (strncmp(tmp->bus_id, bus_id, DASD_BUS_ID_SIZE) == 0) {
 414                         devmap = tmp;
 415                         break;
 416                 }
 417         if (!devmap) {
 418                 /* This bus_id is new. */
 419                 new->devindex = dasd_max_devindex++;
 420                 strncpy(new->bus_id, bus_id, DASD_BUS_ID_SIZE);
 421                 new->features = features;
 422                 new->device = NULL;
 423                 list_add(&new->list, &dasd_hashlists[hash]);
 424                 devmap = new;
 425                 new = NULL;
 426         }
 427         spin_unlock(&dasd_devmap_lock);
 428         kfree(new);
 429         return devmap;
 430 }
 431
 432 /*
 433  * Find devmap for device with given bus_id.
 434  */
 435 static struct dasd_devmap *
 436 dasd_find_busid(const char *bus_id)
 437 {
 438         struct dasd_devmap *devmap, *tmp;
 439         int hash;
 440
 441         spin_lock(&dasd_devmap_lock);
 442         devmap = ERR_PTR(-ENODEV);
 443         hash = dasd_hash_busid(bus_id);
 444         list_for_each_entry(tmp, &dasd_hashlists[hash], list) {
 445                 if (strncmp(tmp->bus_id, bus_id, DASD_BUS_ID_SIZE) == 0) {
 446                         devmap = tmp;
 447                         break;
 448                 }
 449         }
 450         spin_unlock(&dasd_devmap_lock);
 451         return devmap;
 452 }
 453
 454 /*
 455  * Check if busid has been added to the list of dasd ranges.
 456  */
 457 int
 458 dasd_busid_known(const char *bus_id)
 459 {
 460         return IS_ERR(dasd_find_busid(bus_id)) ? -ENOENT : 0;
 461 }
 462
 463 /*
 464  * Forget all about the device numbers added so far.
 465  * This may only be called at module unload or system shutdown.
 466  */
 467 static void
 468 dasd_forget_ranges(void)
 469 {
 470         struct dasd_devmap *devmap, *n;
 471         int i;
 472
 473         spin_lock(&dasd_devmap_lock);
 474         for (i = 0; i < 256; i++) {
 475                 list_for_each_entry_safe(devmap, n, &dasd_hashlists[i], list) {
 476                         BUG_ON(devmap->device != NULL);
 477                         list_del(&devmap->list);
 478                         kfree(devmap);
 479                 }
 480         }
 481         spin_unlock(&dasd_devmap_lock);
 482 }
 483
 484 /*
 485  * Find the device struct by its device index.
 486  */
 487 struct dasd_device *
 488 dasd_device_from_devindex(int devindex)
 489 {
 490         struct dasd_devmap *devmap, *tmp;
 491         struct dasd_device *device;
 492         int i;
 493
 494         spin_lock(&dasd_devmap_lock);
 495         devmap = NULL;
 496         for (i = 0; (i < 256) && !devmap; i++)
 497                 list_for_each_entry(tmp, &dasd_hashlists[i], list)
 498                         if (tmp->devindex == devindex) {
 499                                 /* Found the devmap for the device. */
 500                                 devmap = tmp;
 501                                 break;
 502                         }
 503         if (devmap && devmap->device) {
 504                 device = devmap->device;
 505                 dasd_get_device(device);
 506         } else
 507                 device = ERR_PTR(-ENODEV);
 508         spin_unlock(&dasd_devmap_lock);
 509         return device;
 510 }
 511
 512 /*
 513  * Return devmap for cdev. If no devmap exists yet, create one and
 514  * connect it to the cdev.
 515  */
 516 static struct dasd_devmap *
 517 dasd_devmap_from_cdev(struct ccw_device *cdev)
 518 {
 519         struct dasd_devmap *devmap;
 520
 521         devmap = dasd_find_busid(dev_name(&cdev->dev));
 522         if (IS_ERR(devmap))
 523                 devmap = dasd_add_busid(dev_name(&cdev->dev),
 524                                         DASD_FEATURE_DEFAULT);
 525         return devmap;
 526 }
 527
 528 /*
 529  * Create a dasd device structure for cdev.
 530  */
 531 struct dasd_device *
 532 dasd_create_device(struct ccw_device *cdev)
 533 {
 534         struct dasd_devmap *devmap;
 535         struct dasd_device *device;
 536         unsigned long flags;
 537         int rc;
 538
 539         devmap = dasd_devmap_from_cdev(cdev);
 540         if (IS_ERR(devmap))
 541                 return (void *) devmap;
 542
 543         device = dasd_alloc_device();
 544         if (IS_ERR(device))
 545                 return device;
 546         atomic_set(&device->ref_count, 3);
 547
 548         spin_lock(&dasd_devmap_lock);
 549         if (!devmap->device) {
 550                 devmap->device = device;
 551                 device->devindex = devmap->devindex;
 552                 device->features = devmap->features;
 553                 get_device(&cdev->dev);
 554                 device->cdev = cdev;
 555                 rc = 0;
 556         } else
 557                 /* Someone else was faster. */
 558                 rc = -EBUSY;
 559         spin_unlock(&dasd_devmap_lock);
 560
 561         if (rc) {
 562                 dasd_free_device(device);
 563                 return ERR_PTR(rc);
 564         }
 565
 566         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
 567         dev_set_drvdata(&cdev->dev, device);
 568         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
 569
 570         return device;
 571 }
 572
 573 /*
 574  * Wait queue for dasd_delete_device waits.
 575  */
 576 static DECLARE_WAIT_QUEUE_HEAD(dasd_delete_wq);
 577
 578 /*
 579  * Remove a dasd device structure. The passed referenced
 580  * is destroyed.
 581  */
 582 void
 583 dasd_delete_device(struct dasd_device *device)
 584 {
 585         struct ccw_device *cdev;
 586         struct dasd_devmap *devmap;
 587         unsigned long flags;
 588
 589         /* First remove device pointer from devmap. */
 590         devmap = dasd_find_busid(dev_name(&device->cdev->dev));
 591         BUG_ON(IS_ERR(devmap));
 592         spin_lock(&dasd_devmap_lock);
 593         if (devmap->device != device) {
 594                 spin_unlock(&dasd_devmap_lock);
 595                 dasd_put_device(device);
 596                 return;
 597         }
 598         devmap->device = NULL;
 599         spin_unlock(&dasd_devmap_lock);
 600
 601         /* Disconnect dasd_device structure from ccw_device structure. */
 602         spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
 603         dev_set_drvdata(&device->cdev->dev, NULL);
 604         spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
 605
 606         /*
 607          * Drop ref_count by 3, one for the devmap reference, one for
 608          * the cdev reference and one for the passed reference.
 609          */
 610         atomic_sub(3, &device->ref_count);
 611
 612         /* Wait for reference counter to drop to zero. */
 613         wait_event(dasd_delete_wq, atomic_read(&device->ref_count) == 0);
 614
 615         /* Disconnect dasd_device structure from ccw_device structure. */
 616         cdev = device->cdev;
 617         device->cdev = NULL;
 618
 619         /* Put ccw_device structure. */
 620         put_device(&cdev->dev);
 621
 622         /* Now the device structure can be freed. */
 623         dasd_free_device(device);
 624 }
 625
 626 /*
 627  * Reference counter dropped to zero. Wake up waiter
 628  * in dasd_delete_device.
 629  */
 630 void
 631 dasd_put_device_wake(struct dasd_device *device)
 632 {
 633         wake_up(&dasd_delete_wq);
 634 }
 635
 636 /*
 637  * Return dasd_device structure associated with cdev.
 638  * This function needs to be called with the ccw device
 639  * lock held. It can be used from interrupt context.
 640  */
 641 struct dasd_device *
 642 dasd_device_from_cdev_locked(struct ccw_device *cdev)
 643 {
 644         struct dasd_device *device = dev_get_drvdata(&cdev->dev);
 645
 646         if (!device)
 647                 return ERR_PTR(-ENODEV);
 648         dasd_get_device(device);
 649         return device;
 650 }
 651
 652 /*
 653  * Return dasd_device structure associated with cdev.
 654  */
 655 struct dasd_device *
 656 dasd_device_from_cdev(struct ccw_device *cdev)
 657 {
 658         struct dasd_device *device;
 659         unsigned long flags;
 660
 661         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
 662         device = dasd_device_from_cdev_locked(cdev);
 663         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
 664         return device;
 665 }
 666
 667 /*
 668  * SECTION: files in sysfs
 669  */
 670
 671 /*
 672  * failfast controls the behaviour, if no path is available
 673  */
 674 static ssize_t dasd_ff_show(struct device *dev, struct device_attribute *attr,
 675                             char *buf)
 676 {
 677         struct dasd_devmap *devmap;
 678         int ff_flag;
 679
 680         devmap = dasd_find_busid(dev->bus_id);
 681         if (!IS_ERR(devmap))
 682                 ff_flag = (devmap->features & DASD_FEATURE_FAILFAST) != 0;
 683         else
 684                 ff_flag = (DASD_FEATURE_DEFAULT & DASD_FEATURE_FAILFAST) != 0;
 685         return snprintf(buf, PAGE_SIZE, ff_flag ? "1\n" : "0\n");
 686 }
 687
 688 static ssize_t dasd_ff_store(struct device *dev, struct device_attribute *attr,
 689               const char *buf, size_t count)
 690 {
 691         struct dasd_devmap *devmap;
 692         int val;
 693         char *endp;
 694
 695         devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
 696         if (IS_ERR(devmap))
 697                 return PTR_ERR(devmap);
 698
 699         val = simple_strtoul(buf, &endp, 0);
 700         if (((endp + 1) < (buf + count)) || (val > 1))
 701                 return -EINVAL;
 702
 703         spin_lock(&dasd_devmap_lock);
 704         if (val)
 705                 devmap->features |= DASD_FEATURE_FAILFAST;
 706         else
 707                 devmap->features &= ~DASD_FEATURE_FAILFAST;
 708         if (devmap->device)
 709                 devmap->device->features = devmap->features;
 710         spin_unlock(&dasd_devmap_lock);
 711         return count;
 712 }
 713
 714 static DEVICE_ATTR(failfast, 0644, dasd_ff_show, dasd_ff_store);
 715
 716 /*
 717  * readonly controls the readonly status of a dasd
 718  */
 719 static ssize_t
 720 dasd_ro_show(struct device *dev, struct device_attribute *attr, char *buf)
 721 {
 722         struct dasd_devmap *devmap;
 723         int ro_flag;
 724
 725         devmap = dasd_find_busid(dev_name(dev));
 726         if (!IS_ERR(devmap))
 727                 ro_flag = (devmap->features & DASD_FEATURE_READONLY) != 0;
 728         else
 729                 ro_flag = (DASD_FEATURE_DEFAULT & DASD_FEATURE_READONLY) != 0;
 730         return snprintf(buf, PAGE_SIZE, ro_flag ? "1\n" : "0\n");
 731 }
 732
 733 static ssize_t
 734 dasd_ro_store(struct device *dev, struct device_attribute *attr,
 735               const char *buf, size_t count)
 736 {
 737         struct dasd_devmap *devmap;
 738         int val;
 739         char *endp;
 740
 741         devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
 742         if (IS_ERR(devmap))
 743                 return PTR_ERR(devmap);
 744
 745         val = simple_strtoul(buf, &endp, 0);
 746         if (((endp + 1) < (buf + count)) || (val > 1))
 747                 return -EINVAL;
 748
 749         spin_lock(&dasd_devmap_lock);
 750         if (val)
 751                 devmap->features |= DASD_FEATURE_READONLY;
 752         else
 753                 devmap->features &= ~DASD_FEATURE_READONLY;
 754         if (devmap->device)
 755                 devmap->device->features = devmap->features;
 756         if (devmap->device && devmap->device->block
 757             && devmap->device->block->gdp)
 758                 set_disk_ro(devmap->device->block->gdp, val);
 759         spin_unlock(&dasd_devmap_lock);
 760         return count;
 761 }
 762
 763 static DEVICE_ATTR(readonly, 0644, dasd_ro_show, dasd_ro_store);
 764 /*
 765  * erplog controls the logging of ERP related data
 766  * (e.g. failing channel programs).
 767  */
 768 static ssize_t
 769 dasd_erplog_show(struct device *dev, struct device_attribute *attr, char *buf)
 770 {
 771         struct dasd_devmap *devmap;
 772         int erplog;
 773
 774         devmap = dasd_find_busid(dev_name(dev));
 775         if (!IS_ERR(devmap))
 776                 erplog = (devmap->features & DASD_FEATURE_ERPLOG) != 0;
 777         else
 778                 erplog = (DASD_FEATURE_DEFAULT & DASD_FEATURE_ERPLOG) != 0;
 779         return snprintf(buf, PAGE_SIZE, erplog ? "1\n" : "0\n");
 780 }
 781
 782 static ssize_t
 783 dasd_erplog_store(struct device *dev, struct device_attribute *attr,
 784               const char *buf, size_t count)
 785 {
 786         struct dasd_devmap *devmap;
 787         int val;
 788         char *endp;
 789
 790         devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
 791         if (IS_ERR(devmap))
 792                 return PTR_ERR(devmap);
 793
 794         val = simple_strtoul(buf, &endp, 0);
 795         if (((endp + 1) < (buf + count)) || (val > 1))
 796                 return -EINVAL;
 797
 798         spin_lock(&dasd_devmap_lock);
 799         if (val)
 800                 devmap->features |= DASD_FEATURE_ERPLOG;
 801         else
 802                 devmap->features &= ~DASD_FEATURE_ERPLOG;
 803         if (devmap->device)
 804                 devmap->device->features = devmap->features;
 805         spin_unlock(&dasd_devmap_lock);
 806         return count;
 807 }
 808
 809 static DEVICE_ATTR(erplog, 0644, dasd_erplog_show, dasd_erplog_store);
 810
 811 /*
 812  * use_diag controls whether the driver should use diag rather than ssch
 813  * to talk to the device
 814  */
 815 static ssize_t
 816 dasd_use_diag_show(struct device *dev, struct device_attribute *attr, char *buf)
 817 {
 818         struct dasd_devmap *devmap;
 819         int use_diag;
 820
 821         devmap = dasd_find_busid(dev_name(dev));
 822         if (!IS_ERR(devmap))
 823                 use_diag = (devmap->features & DASD_FEATURE_USEDIAG) != 0;
 824         else
 825                 use_diag = (DASD_FEATURE_DEFAULT & DASD_FEATURE_USEDIAG) != 0;
 826         return sprintf(buf, use_diag ? "1\n" : "0\n");
 827 }
 828
 829 static ssize_t
 830 dasd_use_diag_store(struct device *dev, struct device_attribute *attr,
 831                     const char *buf, size_t count)
 832 {
 833         struct dasd_devmap *devmap;
 834         ssize_t rc;
 835         int val;
 836         char *endp;
 837
 838         devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
 839         if (IS_ERR(devmap))
 840                 return PTR_ERR(devmap);
 841
 842         val = simple_strtoul(buf, &endp, 0);
 843         if (((endp + 1) < (buf + count)) || (val > 1))
 844                 return -EINVAL;
 845
 846         spin_lock(&dasd_devmap_lock);
 847         /* Changing diag discipline flag is only allowed in offline state. */
 848         rc = count;
 849         if (!devmap->device) {
 850                 if (val)
 851                         devmap->features |= DASD_FEATURE_USEDIAG;
 852                 else
 853                         devmap->features &= ~DASD_FEATURE_USEDIAG;
 854         } else
 855                 rc = -EPERM;
 856         spin_unlock(&dasd_devmap_lock);
 857         return rc;
 858 }
 859
 860 static DEVICE_ATTR(use_diag, 0644, dasd_use_diag_show, dasd_use_diag_store);
 861
 862 static ssize_t
 863 dasd_discipline_show(struct device *dev, struct device_attribute *attr,
 864                      char *buf)
 865 {
 866         struct dasd_device *device;
 867         ssize_t len;
 868
 869         device = dasd_device_from_cdev(to_ccwdev(dev));
 870         if (!IS_ERR(device) && device->discipline) {
 871                 len = snprintf(buf, PAGE_SIZE, "%s\n",
 872                                device->discipline->name);
 873                 dasd_put_device(device);
 874         } else
 875                 len = snprintf(buf, PAGE_SIZE, "none\n");
 876         return len;
 877 }
 878
 879 static DEVICE_ATTR(discipline, 0444, dasd_discipline_show, NULL);
 880
 881 static ssize_t
 882 dasd_device_status_show(struct device *dev, struct device_attribute *attr,
 883                      char *buf)
 884 {
 885         struct dasd_device *device;
 886         ssize_t len;
 887
 888         device = dasd_device_from_cdev(to_ccwdev(dev));
 889         if (!IS_ERR(device)) {
 890                 switch (device->state) {
 891                 case DASD_STATE_NEW:
 892                         len = snprintf(buf, PAGE_SIZE, "new\n");
 893                         break;
 894                 case DASD_STATE_KNOWN:
 895                         len = snprintf(buf, PAGE_SIZE, "detected\n");
 896                         break;
 897                 case DASD_STATE_BASIC:
 898                         len = snprintf(buf, PAGE_SIZE, "basic\n");
 899                         break;
 900                 case DASD_STATE_UNFMT:
 901                         len = snprintf(buf, PAGE_SIZE, "unformatted\n");
 902                         break;
 903                 case DASD_STATE_READY:
 904                         len = snprintf(buf, PAGE_SIZE, "ready\n");
 905                         break;
 906                 case DASD_STATE_ONLINE:
 907                         len = snprintf(buf, PAGE_SIZE, "online\n");
 908                         break;
 909                 default:
 910                         len = snprintf(buf, PAGE_SIZE, "no stat\n");
 911                         break;
 912                 }
 913                 dasd_put_device(device);
 914         } else
 915                 len = snprintf(buf, PAGE_SIZE, "unknown\n");
 916         return len;
 917 }
 918
 919 static DEVICE_ATTR(status, 0444, dasd_device_status_show, NULL);
 920
 921 static ssize_t
 922 dasd_alias_show(struct device *dev, struct device_attribute *attr, char *buf)
 923 {
 924         struct dasd_devmap *devmap;
 925         int alias;
 926
 927         devmap = dasd_find_busid(dev_name(dev));
 928         spin_lock(&dasd_devmap_lock);
 929         if (IS_ERR(devmap) || strlen(devmap->uid.vendor) == 0) {
 930                 spin_unlock(&dasd_devmap_lock);
 931                 return sprintf(buf, "0\n");
 932         }
 933         if (devmap->uid.type == UA_BASE_PAV_ALIAS ||
 934             devmap->uid.type == UA_HYPER_PAV_ALIAS)
 935                 alias = 1;
 936         else
 937                 alias = 0;
 938         spin_unlock(&dasd_devmap_lock);
 939         return sprintf(buf, alias ? "1\n" : "0\n");
 940 }
 941
 942 static DEVICE_ATTR(alias, 0444, dasd_alias_show, NULL);
 943
 944 static ssize_t
 945 dasd_vendor_show(struct device *dev, struct device_attribute *attr, char *buf)
 946 {
 947         struct dasd_devmap *devmap;
 948         char *vendor;
 949
 950         devmap = dasd_find_busid(dev_name(dev));
 951         spin_lock(&dasd_devmap_lock);
 952         if (!IS_ERR(devmap) && strlen(devmap->uid.vendor) > 0)
 953                 vendor = devmap->uid.vendor;
 954         else
 955                 vendor = "";
 956         spin_unlock(&dasd_devmap_lock);
 957
 958         return snprintf(buf, PAGE_SIZE, "%s\n", vendor);
 959 }
 960
 961 static DEVICE_ATTR(vendor, 0444, dasd_vendor_show, NULL);
 962
 963 #define UID_STRLEN ( /* vendor */ 3 + 1 + /* serial    */ 14 + 1 +\
 964                      /* SSID   */ 4 + 1 + /* unit addr */ 2 + 1 +\
 965                      /* vduit */ 32 + 1)
 966
 967 static ssize_t
 968 dasd_uid_show(struct device *dev, struct device_attribute *attr, char *buf)
 969 {
 970         struct dasd_devmap *devmap;
 971         char uid_string[UID_STRLEN];
 972         char ua_string[3];
 973         struct dasd_uid *uid;
 974
 975         devmap = dasd_find_busid(dev_name(dev));
 976         spin_lock(&dasd_devmap_lock);
 977         if (IS_ERR(devmap) || strlen(devmap->uid.vendor) == 0) {
 978                 spin_unlock(&dasd_devmap_lock);
 979                 return sprintf(buf, "\n");
 980         }
 981         uid = &devmap->uid;
 982         switch (uid->type) {
 983         case UA_BASE_DEVICE:
 984                 sprintf(ua_string, "%02x", uid->real_unit_addr);
 985                 break;
 986         case UA_BASE_PAV_ALIAS:
 987                 sprintf(ua_string, "%02x", uid->base_unit_addr);
 988                 break;
 989         case UA_HYPER_PAV_ALIAS:
 990                 sprintf(ua_string, "xx");
 991                 break;
 992         default:
 993                 /* should not happen, treat like base device */
 994                 sprintf(ua_string, "%02x", uid->real_unit_addr);
 995                 break;
 996         }
 997         if (strlen(uid->vduit) > 0)
 998                 snprintf(uid_string, sizeof(uid_string),
 999                          "%s.%s.%04x.%s.%s",
1000                          uid->vendor, uid->serial,
1001                          uid->ssid, ua_string,
1002                          uid->vduit);
1003         else
1004                 snprintf(uid_string, sizeof(uid_string),
1005                          "%s.%s.%04x.%s",
1006                          uid->vendor, uid->serial,
1007                          uid->ssid, ua_string);
1008         spin_unlock(&dasd_devmap_lock);
1009         return snprintf(buf, PAGE_SIZE, "%s\n", uid_string);
1010 }
1011
1012 static DEVICE_ATTR(uid, 0444, dasd_uid_show, NULL);
1013
1014 /*
1015  * extended error-reporting
1016  */
1017 static ssize_t
1018 dasd_eer_show(struct device *dev, struct device_attribute *attr, char *buf)
1019 {
1020         struct dasd_devmap *devmap;
1021         int eer_flag;
1022
1023         devmap = dasd_find_busid(dev_name(dev));
1024         if (!IS_ERR(devmap) && devmap->device)
1025                 eer_flag = dasd_eer_enabled(devmap->device);
1026         else
1027                 eer_flag = 0;
1028         return snprintf(buf, PAGE_SIZE, eer_flag ? "1\n" : "0\n");
1029 }
1030
1031 static ssize_t
1032 dasd_eer_store(struct device *dev, struct device_attribute *attr,
1033                const char *buf, size_t count)
1034 {
1035         struct dasd_devmap *devmap;
1036         int val, rc;
1037         char *endp;
1038
1039         devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
1040         if (IS_ERR(devmap))
1041                 return PTR_ERR(devmap);
1042         if (!devmap->device)
1043                 return -ENODEV;
1044
1045         val = simple_strtoul(buf, &endp, 0);
1046         if (((endp + 1) < (buf + count)) || (val > 1))
1047                 return -EINVAL;
1048
1049         if (val) {
1050                 rc = dasd_eer_enable(devmap->device);
1051                 if (rc)
1052                         return rc;
1053         } else
1054                 dasd_eer_disable(devmap->device);
1055         return count;
1056 }
1057
1058 static DEVICE_ATTR(eer_enabled, 0644, dasd_eer_show, dasd_eer_store);
1059
1060 static struct attribute * dasd_attrs[] = {
1061         &dev_attr_readonly.attr,
1062         &dev_attr_discipline.attr,
1063         &dev_attr_status.attr,
1064         &dev_attr_alias.attr,
1065         &dev_attr_vendor.attr,
1066         &dev_attr_uid.attr,
1067         &dev_attr_use_diag.attr,
1068         &dev_attr_eer_enabled.attr,
1069         &dev_attr_erplog.attr,
1070         &dev_attr_failfast.attr,
1071         NULL,
1072 };
1073
1074 static struct attribute_group dasd_attr_group = {
1075         .attrs = dasd_attrs,
1076 };
1077
1078 /*
1079  * Return copy of the device unique identifier.
1080  */
1081 int
1082 dasd_get_uid(struct ccw_device *cdev, struct dasd_uid *uid)
1083 {
1084         struct dasd_devmap *devmap;
1085
1086         devmap = dasd_find_busid(dev_name(&cdev->dev));
1087         if (IS_ERR(devmap))
1088                 return PTR_ERR(devmap);
1089         spin_lock(&dasd_devmap_lock);
1090         *uid = devmap->uid;
1091         spin_unlock(&dasd_devmap_lock);
1092         return 0;
1093 }
1094
1095 /*
1096  * Register the given device unique identifier into devmap struct.
1097  * In addition check if the related storage server subsystem ID is already
1098  * contained in the dasd_server_ssid_list. If subsystem ID is not contained,
1099  * create new entry.
1100  * Return 0 if server was already in serverlist,
1101  *        1 if the server was added successful
1102  *       <0 in case of error.
1103  */
1104 int
1105 dasd_set_uid(struct ccw_device *cdev, struct dasd_uid *uid)
1106 {
1107         struct dasd_devmap *devmap;
1108
1109         devmap = dasd_find_busid(dev_name(&cdev->dev));
1110         if (IS_ERR(devmap))
1111                 return PTR_ERR(devmap);
1112
1113         spin_lock(&dasd_devmap_lock);
1114         devmap->uid = *uid;
1115         spin_unlock(&dasd_devmap_lock);
1116
1117         return 0;
1118 }
1119 EXPORT_SYMBOL_GPL(dasd_set_uid);
1120
1121 /*
1122  * Return value of the specified feature.
1123  */
1124 int
1125 dasd_get_feature(struct ccw_device *cdev, int feature)
1126 {
1127         struct dasd_devmap *devmap;
1128
1129         devmap = dasd_find_busid(dev_name(&cdev->dev));
1130         if (IS_ERR(devmap))
1131                 return PTR_ERR(devmap);
1132
1133         return ((devmap->features & feature) != 0);
1134 }
1135
1136 /*
1137  * Set / reset given feature.
1138  * Flag indicates wether to set (!=0) or the reset (=0) the feature.
1139  */
1140 int
1141 dasd_set_feature(struct ccw_device *cdev, int feature, int flag)
1142 {
1143         struct dasd_devmap *devmap;
1144
1145         devmap = dasd_find_busid(dev_name(&cdev->dev));
1146         if (IS_ERR(devmap))
1147                 return PTR_ERR(devmap);
1148
1149         spin_lock(&dasd_devmap_lock);
1150         if (flag)
1151                 devmap->features |= feature;
1152         else
1153                 devmap->features &= ~feature;
1154         if (devmap->device)
1155                 devmap->device->features = devmap->features;
1156         spin_unlock(&dasd_devmap_lock);
1157         return 0;
1158 }
1159
1160
1161 int
1162 dasd_add_sysfs_files(struct ccw_device *cdev)
1163 {
1164         return sysfs_create_group(&cdev->dev.kobj, &dasd_attr_group);
1165 }
1166
1167 void
1168 dasd_remove_sysfs_files(struct ccw_device *cdev)
1169 {
1170         sysfs_remove_group(&cdev->dev.kobj, &dasd_attr_group);
1171 }
1172
1173
1174 int
1175 dasd_devmap_init(void)
1176 {
1177         int i;
1178
1179         /* Initialize devmap structures. */
1180         dasd_max_devindex = 0;
1181         for (i = 0; i < 256; i++)
1182                 INIT_LIST_HEAD(&dasd_hashlists[i]);
1183         return 0;
1184 }
1185
1186 void
1187 dasd_devmap_exit(void)
1188 {
1189         dasd_forget_ranges();
1190 }