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 {
 210                         MESSAGE(KERN_WARNING,
 211                                 "unsupported feature: %*s, "
 212                                 "ignoring setting", len, str);
 213                         rc = -EINVAL;
 214                 }
 215                 str += len;
 216                 if (*str != ':')
 217                         break;
 218                 str++;
 219         }
 220         if (*str != ')') {
 221                 MESSAGE(KERN_WARNING, "%s",
 222                         "missing ')' in dasd parameter string\n");
 223                 rc = -EINVAL;
 224         } else
 225                 str++;
 226         *endp = str;
 227         if (rc != 0)
 228                 return rc;
 229         return features;
 230 }
 231
 232 /*
 233  * Try to match the first element on the comma separated parse string
 234  * with one of the known keywords. If a keyword is found, take the approprate
 235  * action and return a pointer to the residual string. If the first element
 236  * could not be matched to any keyword then return an error code.
 237  */
 238 static char *
 239 dasd_parse_keyword( char *parsestring ) {
 240
 241         char *nextcomma, *residual_str;
 242         int length;
 243
 244         nextcomma = strchr(parsestring,',');
 245         if (nextcomma) {
 246                 length = nextcomma - parsestring;
 247                 residual_str = nextcomma + 1;
 248         } else {
 249                 length = strlen(parsestring);
 250                 residual_str = parsestring + length;
 251         }
 252         if (strncmp("autodetect", parsestring, length) == 0) {
 253                 dasd_autodetect = 1;
 254                 MESSAGE (KERN_INFO, "%s",
 255                          "turning to autodetection mode");
 256                 return residual_str;
 257         }
 258         if (strncmp("probeonly", parsestring, length) == 0) {
 259                 dasd_probeonly = 1;
 260                 MESSAGE(KERN_INFO, "%s",
 261                         "turning to probeonly mode");
 262                 return residual_str;
 263         }
 264         if (strncmp("nopav", parsestring, length) == 0) {
 265                 if (MACHINE_IS_VM)
 266                         MESSAGE(KERN_INFO, "%s", "'nopav' not supported on VM");
 267                 else {
 268                         dasd_nopav = 1;
 269                         MESSAGE(KERN_INFO, "%s", "disable PAV mode");
 270                 }
 271                 return residual_str;
 272         }
 273         if (strncmp("fixedbuffers", parsestring, length) == 0) {
 274                 if (dasd_page_cache)
 275                         return residual_str;
 276                 dasd_page_cache =
 277                         kmem_cache_create("dasd_page_cache", PAGE_SIZE,
 278                                           PAGE_SIZE, SLAB_CACHE_DMA,
 279                                           NULL);
 280                 if (!dasd_page_cache)
 281                         MESSAGE(KERN_WARNING, "%s", "Failed to create slab, "
 282                                 "fixed buffer mode disabled.");
 283                 else
 284                         MESSAGE (KERN_INFO, "%s",
 285                                  "turning on fixed buffer mode");
 286                 return residual_str;
 287         }
 288         return ERR_PTR(-EINVAL);
 289 }
 290
 291 /*
 292  * Try to interprete the first element on the comma separated parse string
 293  * as a device number or a range of devices. If the interpretation is
 294  * successfull, create the matching dasd_devmap entries and return a pointer
 295  * to the residual string.
 296  * If interpretation fails or in case of an error, return an error code.
 297  */
 298 static char *
 299 dasd_parse_range( char *parsestring ) {
 300
 301         struct dasd_devmap *devmap;
 302         int from, from_id0, from_id1;
 303         int to, to_id0, to_id1;
 304         int features, rc;
 305         char bus_id[DASD_BUS_ID_SIZE+1], *str;
 306
 307         str = parsestring;
 308         rc = dasd_busid(&str, &from_id0, &from_id1, &from);
 309         if (rc == 0) {
 310                 to = from;
 311                 to_id0 = from_id0;
 312                 to_id1 = from_id1;
 313                 if (*str == '-') {
 314                         str++;
 315                         rc = dasd_busid(&str, &to_id0, &to_id1, &to);
 316                 }
 317         }
 318         if (rc == 0 &&
 319             (from_id0 != to_id0 || from_id1 != to_id1 || from > to))
 320                 rc = -EINVAL;
 321         if (rc) {
 322                 MESSAGE(KERN_ERR, "Invalid device range %s", parsestring);
 323                 return ERR_PTR(rc);
 324         }
 325         features = dasd_feature_list(str, &str);
 326         if (features < 0)
 327                 return ERR_PTR(-EINVAL);
 328         /* each device in dasd= parameter should be set initially online */
 329         features |= DASD_FEATURE_INITIAL_ONLINE;
 330         while (from <= to) {
 331                 sprintf(bus_id, "%01x.%01x.%04x",
 332                         from_id0, from_id1, from++);
 333                 devmap = dasd_add_busid(bus_id, features);
 334                 if (IS_ERR(devmap))
 335                         return (char *)devmap;
 336         }
 337         if (*str == ',')
 338                 return str + 1;
 339         if (*str == '\0')
 340                 return str;
 341         MESSAGE(KERN_WARNING,
 342                 "junk at end of dasd parameter string: %s\n", str);
 343         return ERR_PTR(-EINVAL);
 344 }
 345
 346 static char *
 347 dasd_parse_next_element( char *parsestring ) {
 348         char * residual_str;
 349         residual_str = dasd_parse_keyword(parsestring);
 350         if (!IS_ERR(residual_str))
 351                 return residual_str;
 352         residual_str = dasd_parse_range(parsestring);
 353         return residual_str;
 354 }
 355
 356 /*
 357  * Parse parameters stored in dasd[]
 358  * The 'dasd=...' parameter allows to specify a comma separated list of
 359  * keywords and device ranges. When the dasd driver is build into the kernel,
 360  * the complete list will be stored as one element of the dasd[] array.
 361  * When the dasd driver is build as a module, then the list is broken into
 362  * it's elements and each dasd[] entry contains one element.
 363  */
 364 int
 365 dasd_parse(void)
 366 {
 367         int rc, i;
 368         char *parsestring;
 369
 370         rc = 0;
 371         for (i = 0; i < 256; i++) {
 372                 if (dasd[i] == NULL)
 373                         break;
 374                 parsestring = dasd[i];
 375                 /* loop over the comma separated list in the parsestring */
 376                 while (*parsestring) {
 377                         parsestring = dasd_parse_next_element(parsestring);
 378                         if(IS_ERR(parsestring)) {
 379                                 rc = PTR_ERR(parsestring);
 380                                 break;
 381                         }
 382                 }
 383                 if (rc) {
 384                         DBF_EVENT(DBF_ALERT, "%s", "invalid range found");
 385                         break;
 386                 }
 387         }
 388         return rc;
 389 }
 390
 391 /*
 392  * Add a devmap for the device specified by busid. It is possible that
 393  * the devmap already exists (dasd= parameter). The order of the devices
 394  * added through this function will define the kdevs for the individual
 395  * devices.
 396  */
 397 static struct dasd_devmap *
 398 dasd_add_busid(const char *bus_id, int features)
 399 {
 400         struct dasd_devmap *devmap, *new, *tmp;
 401         int hash;
 402
 403         new = (struct dasd_devmap *)
 404                 kzalloc(sizeof(struct dasd_devmap), GFP_KERNEL);
 405         if (!new)
 406                 return ERR_PTR(-ENOMEM);
 407         spin_lock(&dasd_devmap_lock);
 408         devmap = NULL;
 409         hash = dasd_hash_busid(bus_id);
 410         list_for_each_entry(tmp, &dasd_hashlists[hash], list)
 411                 if (strncmp(tmp->bus_id, bus_id, DASD_BUS_ID_SIZE) == 0) {
 412                         devmap = tmp;
 413                         break;
 414                 }
 415         if (!devmap) {
 416                 /* This bus_id is new. */
 417                 new->devindex = dasd_max_devindex++;
 418                 strncpy(new->bus_id, bus_id, DASD_BUS_ID_SIZE);
 419                 new->features = features;
 420                 new->device = NULL;
 421                 list_add(&new->list, &dasd_hashlists[hash]);
 422                 devmap = new;
 423                 new = NULL;
 424         }
 425         spin_unlock(&dasd_devmap_lock);
 426         kfree(new);
 427         return devmap;
 428 }
 429
 430 /*
 431  * Find devmap for device with given bus_id.
 432  */
 433 static struct dasd_devmap *
 434 dasd_find_busid(const char *bus_id)
 435 {
 436         struct dasd_devmap *devmap, *tmp;
 437         int hash;
 438
 439         spin_lock(&dasd_devmap_lock);
 440         devmap = ERR_PTR(-ENODEV);
 441         hash = dasd_hash_busid(bus_id);
 442         list_for_each_entry(tmp, &dasd_hashlists[hash], list) {
 443                 if (strncmp(tmp->bus_id, bus_id, DASD_BUS_ID_SIZE) == 0) {
 444                         devmap = tmp;
 445                         break;
 446                 }
 447         }
 448         spin_unlock(&dasd_devmap_lock);
 449         return devmap;
 450 }
 451
 452 /*
 453  * Check if busid has been added to the list of dasd ranges.
 454  */
 455 int
 456 dasd_busid_known(const char *bus_id)
 457 {
 458         return IS_ERR(dasd_find_busid(bus_id)) ? -ENOENT : 0;
 459 }
 460
 461 /*
 462  * Forget all about the device numbers added so far.
 463  * This may only be called at module unload or system shutdown.
 464  */
 465 static void
 466 dasd_forget_ranges(void)
 467 {
 468         struct dasd_devmap *devmap, *n;
 469         int i;
 470
 471         spin_lock(&dasd_devmap_lock);
 472         for (i = 0; i < 256; i++) {
 473                 list_for_each_entry_safe(devmap, n, &dasd_hashlists[i], list) {
 474                         BUG_ON(devmap->device != NULL);
 475                         list_del(&devmap->list);
 476                         kfree(devmap);
 477                 }
 478         }
 479         spin_unlock(&dasd_devmap_lock);
 480 }
 481
 482 /*
 483  * Find the device struct by its device index.
 484  */
 485 struct dasd_device *
 486 dasd_device_from_devindex(int devindex)
 487 {
 488         struct dasd_devmap *devmap, *tmp;
 489         struct dasd_device *device;
 490         int i;
 491
 492         spin_lock(&dasd_devmap_lock);
 493         devmap = NULL;
 494         for (i = 0; (i < 256) && !devmap; i++)
 495                 list_for_each_entry(tmp, &dasd_hashlists[i], list)
 496                         if (tmp->devindex == devindex) {
 497                                 /* Found the devmap for the device. */
 498                                 devmap = tmp;
 499                                 break;
 500                         }
 501         if (devmap && devmap->device) {
 502                 device = devmap->device;
 503                 dasd_get_device(device);
 504         } else
 505                 device = ERR_PTR(-ENODEV);
 506         spin_unlock(&dasd_devmap_lock);
 507         return device;
 508 }
 509
 510 /*
 511  * Return devmap for cdev. If no devmap exists yet, create one and
 512  * connect it to the cdev.
 513  */
 514 static struct dasd_devmap *
 515 dasd_devmap_from_cdev(struct ccw_device *cdev)
 516 {
 517         struct dasd_devmap *devmap;
 518
 519         devmap = dasd_find_busid(dev_name(&cdev->dev));
 520         if (IS_ERR(devmap))
 521                 devmap = dasd_add_busid(dev_name(&cdev->dev),
 522                                         DASD_FEATURE_DEFAULT);
 523         return devmap;
 524 }
 525
 526 /*
 527  * Create a dasd device structure for cdev.
 528  */
 529 struct dasd_device *
 530 dasd_create_device(struct ccw_device *cdev)
 531 {
 532         struct dasd_devmap *devmap;
 533         struct dasd_device *device;
 534         unsigned long flags;
 535         int rc;
 536
 537         devmap = dasd_devmap_from_cdev(cdev);
 538         if (IS_ERR(devmap))
 539                 return (void *) devmap;
 540
 541         device = dasd_alloc_device();
 542         if (IS_ERR(device))
 543                 return device;
 544         atomic_set(&device->ref_count, 3);
 545
 546         spin_lock(&dasd_devmap_lock);
 547         if (!devmap->device) {
 548                 devmap->device = device;
 549                 device->devindex = devmap->devindex;
 550                 device->features = devmap->features;
 551                 get_device(&cdev->dev);
 552                 device->cdev = cdev;
 553                 rc = 0;
 554         } else
 555                 /* Someone else was faster. */
 556                 rc = -EBUSY;
 557         spin_unlock(&dasd_devmap_lock);
 558
 559         if (rc) {
 560                 dasd_free_device(device);
 561                 return ERR_PTR(rc);
 562         }
 563
 564         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
 565         dev_set_drvdata(&cdev->dev, device);
 566         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
 567
 568         return device;
 569 }
 570
 571 /*
 572  * Wait queue for dasd_delete_device waits.
 573  */
 574 static DECLARE_WAIT_QUEUE_HEAD(dasd_delete_wq);
 575
 576 /*
 577  * Remove a dasd device structure. The passed referenced
 578  * is destroyed.
 579  */
 580 void
 581 dasd_delete_device(struct dasd_device *device)
 582 {
 583         struct ccw_device *cdev;
 584         struct dasd_devmap *devmap;
 585         unsigned long flags;
 586
 587         /* First remove device pointer from devmap. */
 588         devmap = dasd_find_busid(dev_name(&device->cdev->dev));
 589         BUG_ON(IS_ERR(devmap));
 590         spin_lock(&dasd_devmap_lock);
 591         if (devmap->device != device) {
 592                 spin_unlock(&dasd_devmap_lock);
 593                 dasd_put_device(device);
 594                 return;
 595         }
 596         devmap->device = NULL;
 597         spin_unlock(&dasd_devmap_lock);
 598
 599         /* Disconnect dasd_device structure from ccw_device structure. */
 600         spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
 601         dev_set_drvdata(&device->cdev->dev, NULL);
 602         spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
 603
 604         /*
 605          * Drop ref_count by 3, one for the devmap reference, one for
 606          * the cdev reference and one for the passed reference.
 607          */
 608         atomic_sub(3, &device->ref_count);
 609
 610         /* Wait for reference counter to drop to zero. */
 611         wait_event(dasd_delete_wq, atomic_read(&device->ref_count) == 0);
 612
 613         /* Disconnect dasd_device structure from ccw_device structure. */
 614         cdev = device->cdev;
 615         device->cdev = NULL;
 616
 617         /* Put ccw_device structure. */
 618         put_device(&cdev->dev);
 619
 620         /* Now the device structure can be freed. */
 621         dasd_free_device(device);
 622 }
 623
 624 /*
 625  * Reference counter dropped to zero. Wake up waiter
 626  * in dasd_delete_device.
 627  */
 628 void
 629 dasd_put_device_wake(struct dasd_device *device)
 630 {
 631         wake_up(&dasd_delete_wq);
 632 }
 633
 634 /*
 635  * Return dasd_device structure associated with cdev.
 636  * This function needs to be called with the ccw device
 637  * lock held. It can be used from interrupt context.
 638  */
 639 struct dasd_device *
 640 dasd_device_from_cdev_locked(struct ccw_device *cdev)
 641 {
 642         struct dasd_device *device = dev_get_drvdata(&cdev->dev);
 643
 644         if (!device)
 645                 return ERR_PTR(-ENODEV);
 646         dasd_get_device(device);
 647         return device;
 648 }
 649
 650 /*
 651  * Return dasd_device structure associated with cdev.
 652  */
 653 struct dasd_device *
 654 dasd_device_from_cdev(struct ccw_device *cdev)
 655 {
 656         struct dasd_device *device;
 657         unsigned long flags;
 658
 659         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
 660         device = dasd_device_from_cdev_locked(cdev);
 661         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
 662         return device;
 663 }
 664
 665 /*
 666  * SECTION: files in sysfs
 667  */
 668
 669 /*
 670  * readonly controls the readonly status of a dasd
 671  */
 672 static ssize_t
 673 dasd_ro_show(struct device *dev, struct device_attribute *attr, char *buf)
 674 {
 675         struct dasd_devmap *devmap;
 676         int ro_flag;
 677
 678         devmap = dasd_find_busid(dev_name(dev));
 679         if (!IS_ERR(devmap))
 680                 ro_flag = (devmap->features & DASD_FEATURE_READONLY) != 0;
 681         else
 682                 ro_flag = (DASD_FEATURE_DEFAULT & DASD_FEATURE_READONLY) != 0;
 683         return snprintf(buf, PAGE_SIZE, ro_flag ? "1\n" : "0\n");
 684 }
 685
 686 static ssize_t
 687 dasd_ro_store(struct device *dev, struct device_attribute *attr,
 688               const char *buf, size_t count)
 689 {
 690         struct dasd_devmap *devmap;
 691         int val;
 692         char *endp;
 693
 694         devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
 695         if (IS_ERR(devmap))
 696                 return PTR_ERR(devmap);
 697
 698         val = simple_strtoul(buf, &endp, 0);
 699         if (((endp + 1) < (buf + count)) || (val > 1))
 700                 return -EINVAL;
 701
 702         spin_lock(&dasd_devmap_lock);
 703         if (val)
 704                 devmap->features |= DASD_FEATURE_READONLY;
 705         else
 706                 devmap->features &= ~DASD_FEATURE_READONLY;
 707         if (devmap->device)
 708                 devmap->device->features = devmap->features;
 709         if (devmap->device && devmap->device->block
 710             && devmap->device->block->gdp)
 711                 set_disk_ro(devmap->device->block->gdp, val);
 712         spin_unlock(&dasd_devmap_lock);
 713         return count;
 714 }
 715
 716 static DEVICE_ATTR(readonly, 0644, dasd_ro_show, dasd_ro_store);
 717 /*
 718  * erplog controls the logging of ERP related data
 719  * (e.g. failing channel programs).
 720  */
 721 static ssize_t
 722 dasd_erplog_show(struct device *dev, struct device_attribute *attr, char *buf)
 723 {
 724         struct dasd_devmap *devmap;
 725         int erplog;
 726
 727         devmap = dasd_find_busid(dev_name(dev));
 728         if (!IS_ERR(devmap))
 729                 erplog = (devmap->features & DASD_FEATURE_ERPLOG) != 0;
 730         else
 731                 erplog = (DASD_FEATURE_DEFAULT & DASD_FEATURE_ERPLOG) != 0;
 732         return snprintf(buf, PAGE_SIZE, erplog ? "1\n" : "0\n");
 733 }
 734
 735 static ssize_t
 736 dasd_erplog_store(struct device *dev, struct device_attribute *attr,
 737               const char *buf, size_t count)
 738 {
 739         struct dasd_devmap *devmap;
 740         int val;
 741         char *endp;
 742
 743         devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
 744         if (IS_ERR(devmap))
 745                 return PTR_ERR(devmap);
 746
 747         val = simple_strtoul(buf, &endp, 0);
 748         if (((endp + 1) < (buf + count)) || (val > 1))
 749                 return -EINVAL;
 750
 751         spin_lock(&dasd_devmap_lock);
 752         if (val)
 753                 devmap->features |= DASD_FEATURE_ERPLOG;
 754         else
 755                 devmap->features &= ~DASD_FEATURE_ERPLOG;
 756         if (devmap->device)
 757                 devmap->device->features = devmap->features;
 758         spin_unlock(&dasd_devmap_lock);
 759         return count;
 760 }
 761
 762 static DEVICE_ATTR(erplog, 0644, dasd_erplog_show, dasd_erplog_store);
 763
 764 /*
 765  * use_diag controls whether the driver should use diag rather than ssch
 766  * to talk to the device
 767  */
 768 static ssize_t
 769 dasd_use_diag_show(struct device *dev, struct device_attribute *attr, char *buf)
 770 {
 771         struct dasd_devmap *devmap;
 772         int use_diag;
 773
 774         devmap = dasd_find_busid(dev_name(dev));
 775         if (!IS_ERR(devmap))
 776                 use_diag = (devmap->features & DASD_FEATURE_USEDIAG) != 0;
 777         else
 778                 use_diag = (DASD_FEATURE_DEFAULT & DASD_FEATURE_USEDIAG) != 0;
 779         return sprintf(buf, use_diag ? "1\n" : "0\n");
 780 }
 781
 782 static ssize_t
 783 dasd_use_diag_store(struct device *dev, struct device_attribute *attr,
 784                     const char *buf, size_t count)
 785 {
 786         struct dasd_devmap *devmap;
 787         ssize_t rc;
 788         int val;
 789         char *endp;
 790
 791         devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
 792         if (IS_ERR(devmap))
 793                 return PTR_ERR(devmap);
 794
 795         val = simple_strtoul(buf, &endp, 0);
 796         if (((endp + 1) < (buf + count)) || (val > 1))
 797                 return -EINVAL;
 798
 799         spin_lock(&dasd_devmap_lock);
 800         /* Changing diag discipline flag is only allowed in offline state. */
 801         rc = count;
 802         if (!devmap->device) {
 803                 if (val)
 804                         devmap->features |= DASD_FEATURE_USEDIAG;
 805                 else
 806                         devmap->features &= ~DASD_FEATURE_USEDIAG;
 807         } else
 808                 rc = -EPERM;
 809         spin_unlock(&dasd_devmap_lock);
 810         return rc;
 811 }
 812
 813 static DEVICE_ATTR(use_diag, 0644, dasd_use_diag_show, dasd_use_diag_store);
 814
 815 static ssize_t
 816 dasd_discipline_show(struct device *dev, struct device_attribute *attr,
 817                      char *buf)
 818 {
 819         struct dasd_device *device;
 820         ssize_t len;
 821
 822         device = dasd_device_from_cdev(to_ccwdev(dev));
 823         if (!IS_ERR(device) && device->discipline) {
 824                 len = snprintf(buf, PAGE_SIZE, "%s\n",
 825                                device->discipline->name);
 826                 dasd_put_device(device);
 827         } else
 828                 len = snprintf(buf, PAGE_SIZE, "none\n");
 829         return len;
 830 }
 831
 832 static DEVICE_ATTR(discipline, 0444, dasd_discipline_show, NULL);
 833
 834 static ssize_t
 835 dasd_device_status_show(struct device *dev, struct device_attribute *attr,
 836                      char *buf)
 837 {
 838         struct dasd_device *device;
 839         ssize_t len;
 840
 841         device = dasd_device_from_cdev(to_ccwdev(dev));
 842         if (!IS_ERR(device)) {
 843                 switch (device->state) {
 844                 case DASD_STATE_NEW:
 845                         len = snprintf(buf, PAGE_SIZE, "new\n");
 846                         break;
 847                 case DASD_STATE_KNOWN:
 848                         len = snprintf(buf, PAGE_SIZE, "detected\n");
 849                         break;
 850                 case DASD_STATE_BASIC:
 851                         len = snprintf(buf, PAGE_SIZE, "basic\n");
 852                         break;
 853                 case DASD_STATE_UNFMT:
 854                         len = snprintf(buf, PAGE_SIZE, "unformatted\n");
 855                         break;
 856                 case DASD_STATE_READY:
 857                         len = snprintf(buf, PAGE_SIZE, "ready\n");
 858                         break;
 859                 case DASD_STATE_ONLINE:
 860                         len = snprintf(buf, PAGE_SIZE, "online\n");
 861                         break;
 862                 default:
 863                         len = snprintf(buf, PAGE_SIZE, "no stat\n");
 864                         break;
 865                 }
 866                 dasd_put_device(device);
 867         } else
 868                 len = snprintf(buf, PAGE_SIZE, "unknown\n");
 869         return len;
 870 }
 871
 872 static DEVICE_ATTR(status, 0444, dasd_device_status_show, NULL);
 873
 874 static ssize_t
 875 dasd_alias_show(struct device *dev, struct device_attribute *attr, char *buf)
 876 {
 877         struct dasd_devmap *devmap;
 878         int alias;
 879
 880         devmap = dasd_find_busid(dev_name(dev));
 881         spin_lock(&dasd_devmap_lock);
 882         if (IS_ERR(devmap) || strlen(devmap->uid.vendor) == 0) {
 883                 spin_unlock(&dasd_devmap_lock);
 884                 return sprintf(buf, "0\n");
 885         }
 886         if (devmap->uid.type == UA_BASE_PAV_ALIAS ||
 887             devmap->uid.type == UA_HYPER_PAV_ALIAS)
 888                 alias = 1;
 889         else
 890                 alias = 0;
 891         spin_unlock(&dasd_devmap_lock);
 892         return sprintf(buf, alias ? "1\n" : "0\n");
 893 }
 894
 895 static DEVICE_ATTR(alias, 0444, dasd_alias_show, NULL);
 896
 897 static ssize_t
 898 dasd_vendor_show(struct device *dev, struct device_attribute *attr, char *buf)
 899 {
 900         struct dasd_devmap *devmap;
 901         char *vendor;
 902
 903         devmap = dasd_find_busid(dev_name(dev));
 904         spin_lock(&dasd_devmap_lock);
 905         if (!IS_ERR(devmap) && strlen(devmap->uid.vendor) > 0)
 906                 vendor = devmap->uid.vendor;
 907         else
 908                 vendor = "";
 909         spin_unlock(&dasd_devmap_lock);
 910
 911         return snprintf(buf, PAGE_SIZE, "%s\n", vendor);
 912 }
 913
 914 static DEVICE_ATTR(vendor, 0444, dasd_vendor_show, NULL);
 915
 916 #define UID_STRLEN ( /* vendor */ 3 + 1 + /* serial    */ 14 + 1 +\
 917                      /* SSID   */ 4 + 1 + /* unit addr */ 2 + 1 +\
 918                      /* vduit */ 32 + 1)
 919
 920 static ssize_t
 921 dasd_uid_show(struct device *dev, struct device_attribute *attr, char *buf)
 922 {
 923         struct dasd_devmap *devmap;
 924         char uid_string[UID_STRLEN];
 925         char ua_string[3];
 926         struct dasd_uid *uid;
 927
 928         devmap = dasd_find_busid(dev_name(dev));
 929         spin_lock(&dasd_devmap_lock);
 930         if (IS_ERR(devmap) || strlen(devmap->uid.vendor) == 0) {
 931                 spin_unlock(&dasd_devmap_lock);
 932                 return sprintf(buf, "\n");
 933         }
 934         uid = &devmap->uid;
 935         switch (uid->type) {
 936         case UA_BASE_DEVICE:
 937                 sprintf(ua_string, "%02x", uid->real_unit_addr);
 938                 break;
 939         case UA_BASE_PAV_ALIAS:
 940                 sprintf(ua_string, "%02x", uid->base_unit_addr);
 941                 break;
 942         case UA_HYPER_PAV_ALIAS:
 943                 sprintf(ua_string, "xx");
 944                 break;
 945         default:
 946                 /* should not happen, treat like base device */
 947                 sprintf(ua_string, "%02x", uid->real_unit_addr);
 948                 break;
 949         }
 950         if (strlen(uid->vduit) > 0)
 951                 snprintf(uid_string, sizeof(uid_string),
 952                          "%s.%s.%04x.%s.%s",
 953                          uid->vendor, uid->serial,
 954                          uid->ssid, ua_string,
 955                          uid->vduit);
 956         else
 957                 snprintf(uid_string, sizeof(uid_string),
 958                          "%s.%s.%04x.%s",
 959                          uid->vendor, uid->serial,
 960                          uid->ssid, ua_string);
 961         spin_unlock(&dasd_devmap_lock);
 962         return snprintf(buf, PAGE_SIZE, "%s\n", uid_string);
 963 }
 964
 965 static DEVICE_ATTR(uid, 0444, dasd_uid_show, NULL);
 966
 967 /*
 968  * extended error-reporting
 969  */
 970 static ssize_t
 971 dasd_eer_show(struct device *dev, struct device_attribute *attr, char *buf)
 972 {
 973         struct dasd_devmap *devmap;
 974         int eer_flag;
 975
 976         devmap = dasd_find_busid(dev_name(dev));
 977         if (!IS_ERR(devmap) && devmap->device)
 978                 eer_flag = dasd_eer_enabled(devmap->device);
 979         else
 980                 eer_flag = 0;
 981         return snprintf(buf, PAGE_SIZE, eer_flag ? "1\n" : "0\n");
 982 }
 983
 984 static ssize_t
 985 dasd_eer_store(struct device *dev, struct device_attribute *attr,
 986                const char *buf, size_t count)
 987 {
 988         struct dasd_devmap *devmap;
 989         int val, rc;
 990         char *endp;
 991
 992         devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
 993         if (IS_ERR(devmap))
 994                 return PTR_ERR(devmap);
 995         if (!devmap->device)
 996                 return -ENODEV;
 997
 998         val = simple_strtoul(buf, &endp, 0);
 999         if (((endp + 1) < (buf + count)) || (val > 1))
1000                 return -EINVAL;
1001
1002         if (val) {
1003                 rc = dasd_eer_enable(devmap->device);
1004                 if (rc)
1005                         return rc;
1006         } else
1007                 dasd_eer_disable(devmap->device);
1008         return count;
1009 }
1010
1011 static DEVICE_ATTR(eer_enabled, 0644, dasd_eer_show, dasd_eer_store);
1012
1013 static struct attribute * dasd_attrs[] = {
1014         &dev_attr_readonly.attr,
1015         &dev_attr_discipline.attr,
1016         &dev_attr_status.attr,
1017         &dev_attr_alias.attr,
1018         &dev_attr_vendor.attr,
1019         &dev_attr_uid.attr,
1020         &dev_attr_use_diag.attr,
1021         &dev_attr_eer_enabled.attr,
1022         &dev_attr_erplog.attr,
1023         NULL,
1024 };
1025
1026 static struct attribute_group dasd_attr_group = {
1027         .attrs = dasd_attrs,
1028 };
1029
1030 /*
1031  * Return copy of the device unique identifier.
1032  */
1033 int
1034 dasd_get_uid(struct ccw_device *cdev, struct dasd_uid *uid)
1035 {
1036         struct dasd_devmap *devmap;
1037
1038         devmap = dasd_find_busid(dev_name(&cdev->dev));
1039         if (IS_ERR(devmap))
1040                 return PTR_ERR(devmap);
1041         spin_lock(&dasd_devmap_lock);
1042         *uid = devmap->uid;
1043         spin_unlock(&dasd_devmap_lock);
1044         return 0;
1045 }
1046
1047 /*
1048  * Register the given device unique identifier into devmap struct.
1049  * In addition check if the related storage server subsystem ID is already
1050  * contained in the dasd_server_ssid_list. If subsystem ID is not contained,
1051  * create new entry.
1052  * Return 0 if server was already in serverlist,
1053  *        1 if the server was added successful
1054  *       <0 in case of error.
1055  */
1056 int
1057 dasd_set_uid(struct ccw_device *cdev, struct dasd_uid *uid)
1058 {
1059         struct dasd_devmap *devmap;
1060
1061         devmap = dasd_find_busid(dev_name(&cdev->dev));
1062         if (IS_ERR(devmap))
1063                 return PTR_ERR(devmap);
1064
1065         spin_lock(&dasd_devmap_lock);
1066         devmap->uid = *uid;
1067         spin_unlock(&dasd_devmap_lock);
1068
1069         return 0;
1070 }
1071 EXPORT_SYMBOL_GPL(dasd_set_uid);
1072
1073 /*
1074  * Return value of the specified feature.
1075  */
1076 int
1077 dasd_get_feature(struct ccw_device *cdev, int feature)
1078 {
1079         struct dasd_devmap *devmap;
1080
1081         devmap = dasd_find_busid(dev_name(&cdev->dev));
1082         if (IS_ERR(devmap))
1083                 return PTR_ERR(devmap);
1084
1085         return ((devmap->features & feature) != 0);
1086 }
1087
1088 /*
1089  * Set / reset given feature.
1090  * Flag indicates wether to set (!=0) or the reset (=0) the feature.
1091  */
1092 int
1093 dasd_set_feature(struct ccw_device *cdev, int feature, int flag)
1094 {
1095         struct dasd_devmap *devmap;
1096
1097         devmap = dasd_find_busid(dev_name(&cdev->dev));
1098         if (IS_ERR(devmap))
1099                 return PTR_ERR(devmap);
1100
1101         spin_lock(&dasd_devmap_lock);
1102         if (flag)
1103                 devmap->features |= feature;
1104         else
1105                 devmap->features &= ~feature;
1106         if (devmap->device)
1107                 devmap->device->features = devmap->features;
1108         spin_unlock(&dasd_devmap_lock);
1109         return 0;
1110 }
1111
1112
1113 int
1114 dasd_add_sysfs_files(struct ccw_device *cdev)
1115 {
1116         return sysfs_create_group(&cdev->dev.kobj, &dasd_attr_group);
1117 }
1118
1119 void
1120 dasd_remove_sysfs_files(struct ccw_device *cdev)
1121 {
1122         sysfs_remove_group(&cdev->dev.kobj, &dasd_attr_group);
1123 }
1124
1125
1126 int
1127 dasd_devmap_init(void)
1128 {
1129         int i;
1130
1131         /* Initialize devmap structures. */
1132         dasd_max_devindex = 0;
1133         for (i = 0; i < 256; i++)
1134                 INIT_LIST_HEAD(&dasd_hashlists[i]);
1135         return 0;
1136 }
1137
1138 void
1139 dasd_devmap_exit(void)
1140 {
1141         dasd_forget_ranges();
1142 }