git.oblomov.eu Git - linux-2.6/blob - drivers/s390/cio/chsc.c

   1 /*
   2  *  drivers/s390/cio/chsc.c
   3  *   S/390 common I/O routines -- channel subsystem call
   4  *
   5  *    Copyright (C) 1999-2002 IBM Deutschland Entwicklung GmbH,
   6  *                            IBM Corporation
   7  *    Author(s): Ingo Adlung (adlung@de.ibm.com)
   8  *               Cornelia Huck (cornelia.huck@de.ibm.com)
   9  *               Arnd Bergmann (arndb@de.ibm.com)
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/config.h>
  14 #include <linux/slab.h>
  15 #include <linux/init.h>
  16 #include <linux/device.h>
  17
  18 #include <asm/cio.h>
  19
  20 #include "css.h"
  21 #include "cio.h"
  22 #include "cio_debug.h"
  23 #include "ioasm.h"
  24 #include "chsc.h"
  25
  26 static void *sei_page;
  27
  28 static int new_channel_path(int chpid);
  29
  30 static inline void
  31 set_chp_logically_online(int chp, int onoff)
  32 {
  33         css[0]->chps[chp]->state = onoff;
  34 }
  35
  36 static int
  37 get_chp_status(int chp)
  38 {
  39         return (css[0]->chps[chp] ? css[0]->chps[chp]->state : -ENODEV);
  40 }
  41
  42 void
  43 chsc_validate_chpids(struct subchannel *sch)
  44 {
  45         int mask, chp;
  46
  47         for (chp = 0; chp <= 7; chp++) {
  48                 mask = 0x80 >> chp;
  49                 if (!get_chp_status(sch->schib.pmcw.chpid[chp]))
  50                         /* disable using this path */
  51                         sch->opm &= ~mask;
  52         }
  53 }
  54
  55 void
  56 chpid_is_actually_online(int chp)
  57 {
  58         int state;
  59
  60         state = get_chp_status(chp);
  61         if (state < 0) {
  62                 need_rescan = 1;
  63                 queue_work(slow_path_wq, &slow_path_work);
  64         } else
  65                 WARN_ON(!state);
  66 }
  67
  68 /* FIXME: this is _always_ called for every subchannel. shouldn't we
  69  *        process more than one at a time? */
  70 static int
  71 chsc_get_sch_desc_irq(struct subchannel *sch, void *page)
  72 {
  73         int ccode, j;
  74
  75         struct {
  76                 struct chsc_header request;
  77                 u16 reserved1a:10;
  78                 u16 ssid:2;
  79                 u16 reserved1b:4;
  80                 u16 f_sch;        /* first subchannel */
  81                 u16 reserved2;
  82                 u16 l_sch;        /* last subchannel */
  83                 u32 reserved3;
  84                 struct chsc_header response;
  85                 u32 reserved4;
  86                 u8 sch_valid : 1;
  87                 u8 dev_valid : 1;
  88                 u8 st        : 3; /* subchannel type */
  89                 u8 zeroes    : 3;
  90                 u8  unit_addr;    /* unit address */
  91                 u16 devno;        /* device number */
  92                 u8 path_mask;
  93                 u8 fla_valid_mask;
  94                 u16 sch;          /* subchannel */
  95                 u8 chpid[8];      /* chpids 0-7 */
  96                 u16 fla[8];       /* full link addresses 0-7 */
  97         } *ssd_area;
  98
  99         ssd_area = page;
 100
 101         ssd_area->request.length = 0x0010;
 102         ssd_area->request.code = 0x0004;
 103
 104         ssd_area->ssid = sch->schid.ssid;
 105         ssd_area->f_sch = sch->schid.sch_no;
 106         ssd_area->l_sch = sch->schid.sch_no;
 107
 108         ccode = chsc(ssd_area);
 109         if (ccode > 0) {
 110                 pr_debug("chsc returned with ccode = %d\n", ccode);
 111                 return (ccode == 3) ? -ENODEV : -EBUSY;
 112         }
 113
 114         switch (ssd_area->response.code) {
 115         case 0x0001: /* everything ok */
 116                 break;
 117         case 0x0002:
 118                 CIO_CRW_EVENT(2, "Invalid command!\n");
 119                 return -EINVAL;
 120         case 0x0003:
 121                 CIO_CRW_EVENT(2, "Error in chsc request block!\n");
 122                 return -EINVAL;
 123         case 0x0004:
 124                 CIO_CRW_EVENT(2, "Model does not provide ssd\n");
 125                 return -EOPNOTSUPP;
 126         default:
 127                 CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
 128                               ssd_area->response.code);
 129                 return -EIO;
 130         }
 131
 132         /*
 133          * ssd_area->st stores the type of the detected
 134          * subchannel, with the following definitions:
 135          *
 136          * 0: I/O subchannel:     All fields have meaning
 137          * 1: CHSC subchannel:    Only sch_val, st and sch
 138          *                        have meaning
 139          * 2: Message subchannel: All fields except unit_addr
 140          *                        have meaning
 141          * 3: ADM subchannel:     Only sch_val, st and sch
 142          *                        have meaning
 143          *
 144          * Other types are currently undefined.
 145          */
 146         if (ssd_area->st > 3) { /* uhm, that looks strange... */
 147                 CIO_CRW_EVENT(0, "Strange subchannel type %d"
 148                               " for sch 0.%x.%04x\n", ssd_area->st,
 149                               sch->schid.ssid, sch->schid.sch_no);
 150                 /*
 151                  * There may have been a new subchannel type defined in the
 152                  * time since this code was written; since we don't know which
 153                  * fields have meaning and what to do with it we just jump out
 154                  */
 155                 return 0;
 156         } else {
 157                 const char *type[4] = {"I/O", "chsc", "message", "ADM"};
 158                 CIO_CRW_EVENT(6, "ssd: sch 0.%x.%04x is %s subchannel\n",
 159                               sch->schid.ssid, sch->schid.sch_no,
 160                               type[ssd_area->st]);
 161
 162                 sch->ssd_info.valid = 1;
 163                 sch->ssd_info.type = ssd_area->st;
 164         }
 165
 166         if (ssd_area->st == 0 || ssd_area->st == 2) {
 167                 for (j = 0; j < 8; j++) {
 168                         if (!((0x80 >> j) & ssd_area->path_mask &
 169                               ssd_area->fla_valid_mask))
 170                                 continue;
 171                         sch->ssd_info.chpid[j] = ssd_area->chpid[j];
 172                         sch->ssd_info.fla[j]   = ssd_area->fla[j];
 173                 }
 174         }
 175         return 0;
 176 }
 177
 178 int
 179 css_get_ssd_info(struct subchannel *sch)
 180 {
 181         int ret;
 182         void *page;
 183
 184         page = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
 185         if (!page)
 186                 return -ENOMEM;
 187         spin_lock_irq(&sch->lock);
 188         ret = chsc_get_sch_desc_irq(sch, page);
 189         if (ret) {
 190                 static int cio_chsc_err_msg;
 191
 192                 if (!cio_chsc_err_msg) {
 193                         printk(KERN_ERR
 194                                "chsc_get_sch_descriptions:"
 195                                " Error %d while doing chsc; "
 196                                "processing some machine checks may "
 197                                "not work\n", ret);
 198                         cio_chsc_err_msg = 1;
 199                 }
 200         }
 201         spin_unlock_irq(&sch->lock);
 202         free_page((unsigned long)page);
 203         if (!ret) {
 204                 int j, chpid;
 205                 /* Allocate channel path structures, if needed. */
 206                 for (j = 0; j < 8; j++) {
 207                         chpid = sch->ssd_info.chpid[j];
 208                         if (chpid && (get_chp_status(chpid) < 0))
 209                             new_channel_path(chpid);
 210                 }
 211         }
 212         return ret;
 213 }
 214
 215 static int
 216 s390_subchannel_remove_chpid(struct device *dev, void *data)
 217 {
 218         int j;
 219         int mask;
 220         struct subchannel *sch;
 221         struct channel_path *chpid;
 222         struct schib schib;
 223
 224         sch = to_subchannel(dev);
 225         chpid = data;
 226         for (j = 0; j < 8; j++)
 227                 if (sch->schib.pmcw.chpid[j] == chpid->id)
 228                         break;
 229         if (j >= 8)
 230                 return 0;
 231
 232         mask = 0x80 >> j;
 233         spin_lock_irq(&sch->lock);
 234
 235         stsch(sch->schid, &schib);
 236         if (!schib.pmcw.dnv)
 237                 goto out_unreg;
 238         memcpy(&sch->schib, &schib, sizeof(struct schib));
 239         /* Check for single path devices. */
 240         if (sch->schib.pmcw.pim == 0x80)
 241                 goto out_unreg;
 242         if (sch->vpm == mask)
 243                 goto out_unreg;
 244
 245         if ((sch->schib.scsw.actl & (SCSW_ACTL_CLEAR_PEND |
 246                                      SCSW_ACTL_HALT_PEND |
 247                                      SCSW_ACTL_START_PEND |
 248                                      SCSW_ACTL_RESUME_PEND)) &&
 249             (sch->schib.pmcw.lpum == mask)) {
 250                 int cc = cio_cancel(sch);
 251
 252                 if (cc == -ENODEV)
 253                         goto out_unreg;
 254
 255                 if (cc == -EINVAL) {
 256                         cc = cio_clear(sch);
 257                         if (cc == -ENODEV)
 258                                 goto out_unreg;
 259                         /* Call handler. */
 260                         if (sch->driver && sch->driver->termination)
 261                                 sch->driver->termination(&sch->dev);
 262                         goto out_unlock;
 263                 }
 264         } else if ((sch->schib.scsw.actl & SCSW_ACTL_DEVACT) &&
 265                    (sch->schib.scsw.actl & SCSW_ACTL_SCHACT) &&
 266                    (sch->schib.pmcw.lpum == mask)) {
 267                 int cc;
 268
 269                 cc = cio_clear(sch);
 270                 if (cc == -ENODEV)
 271                         goto out_unreg;
 272                 /* Call handler. */
 273                 if (sch->driver && sch->driver->termination)
 274                         sch->driver->termination(&sch->dev);
 275                 goto out_unlock;
 276         }
 277
 278         /* trigger path verification. */
 279         if (sch->driver && sch->driver->verify)
 280                 sch->driver->verify(&sch->dev);
 281 out_unlock:
 282         spin_unlock_irq(&sch->lock);
 283         return 0;
 284 out_unreg:
 285         spin_unlock_irq(&sch->lock);
 286         sch->lpm = 0;
 287         if (css_enqueue_subchannel_slow(sch->schid)) {
 288                 css_clear_subchannel_slow_list();
 289                 need_rescan = 1;
 290         }
 291         return 0;
 292 }
 293
 294 static inline void
 295 s390_set_chpid_offline( __u8 chpid)
 296 {
 297         char dbf_txt[15];
 298         struct device *dev;
 299
 300         sprintf(dbf_txt, "chpr%x", chpid);
 301         CIO_TRACE_EVENT(2, dbf_txt);
 302
 303         if (get_chp_status(chpid) <= 0)
 304                 return;
 305         dev = get_device(&css[0]->chps[chpid]->dev);
 306         bus_for_each_dev(&css_bus_type, NULL, to_channelpath(dev),
 307                          s390_subchannel_remove_chpid);
 308
 309         if (need_rescan || css_slow_subchannels_exist())
 310                 queue_work(slow_path_wq, &slow_path_work);
 311         put_device(dev);
 312 }
 313
 314 struct res_acc_data {
 315         struct channel_path *chp;
 316         u32 fla_mask;
 317         u16 fla;
 318 };
 319
 320 static int
 321 s390_process_res_acc_sch(struct res_acc_data *res_data, struct subchannel *sch)
 322 {
 323         int found;
 324         int chp;
 325         int ccode;
 326
 327         found = 0;
 328         for (chp = 0; chp <= 7; chp++)
 329                 /*
 330                  * check if chpid is in information updated by ssd
 331                  */
 332                 if (sch->ssd_info.valid &&
 333                     sch->ssd_info.chpid[chp] == res_data->chp->id &&
 334                     (sch->ssd_info.fla[chp] & res_data->fla_mask)
 335                     == res_data->fla) {
 336                         found = 1;
 337                         break;
 338                 }
 339
 340         if (found == 0)
 341                 return 0;
 342
 343         /*
 344          * Do a stsch to update our subchannel structure with the
 345          * new path information and eventually check for logically
 346          * offline chpids.
 347          */
 348         ccode = stsch(sch->schid, &sch->schib);
 349         if (ccode > 0)
 350                 return 0;
 351
 352         return 0x80 >> chp;
 353 }
 354
 355 static inline int
 356 s390_process_res_acc_new_sch(struct subchannel_id schid)
 357 {
 358         struct schib schib;
 359         int ret;
 360         /*
 361          * We don't know the device yet, but since a path
 362          * may be available now to the device we'll have
 363          * to do recognition again.
 364          * Since we don't have any idea about which chpid
 365          * that beast may be on we'll have to do a stsch
 366          * on all devices, grr...
 367          */
 368         if (stsch_err(schid, &schib))
 369                 /* We're through */
 370                 return need_rescan ? -EAGAIN : -ENXIO;
 371
 372         /* Put it on the slow path. */
 373         ret = css_enqueue_subchannel_slow(schid);
 374         if (ret) {
 375                 css_clear_subchannel_slow_list();
 376                 need_rescan = 1;
 377                 return -EAGAIN;
 378         }
 379         return 0;
 380 }
 381
 382 static int
 383 __s390_process_res_acc(struct subchannel_id schid, void *data)
 384 {
 385         int chp_mask, old_lpm;
 386         struct res_acc_data *res_data;
 387         struct subchannel *sch;
 388
 389         res_data = (struct res_acc_data *)data;
 390         sch = get_subchannel_by_schid(schid);
 391         if (!sch)
 392                 /* Check if a subchannel is newly available. */
 393                 return s390_process_res_acc_new_sch(schid);
 394
 395         spin_lock_irq(&sch->lock);
 396
 397         chp_mask = s390_process_res_acc_sch(res_data, sch);
 398
 399         if (chp_mask == 0) {
 400                 spin_unlock_irq(&sch->lock);
 401                 return 0;
 402         }
 403         old_lpm = sch->lpm;
 404         sch->lpm = ((sch->schib.pmcw.pim &
 405                      sch->schib.pmcw.pam &
 406                      sch->schib.pmcw.pom)
 407                     | chp_mask) & sch->opm;
 408         if (!old_lpm && sch->lpm)
 409                 device_trigger_reprobe(sch);
 410         else if (sch->driver && sch->driver->verify)
 411                 sch->driver->verify(&sch->dev);
 412
 413         spin_unlock_irq(&sch->lock);
 414         put_device(&sch->dev);
 415         return (res_data->fla_mask == 0xffff) ? -ENODEV : 0;
 416 }
 417
 418
 419 static int
 420 s390_process_res_acc (struct res_acc_data *res_data)
 421 {
 422         int rc;
 423         char dbf_txt[15];
 424
 425         sprintf(dbf_txt, "accpr%x", res_data->chp->id);
 426         CIO_TRACE_EVENT( 2, dbf_txt);
 427         if (res_data->fla != 0) {
 428                 sprintf(dbf_txt, "fla%x", res_data->fla);
 429                 CIO_TRACE_EVENT( 2, dbf_txt);
 430         }
 431
 432         /*
 433          * I/O resources may have become accessible.
 434          * Scan through all subchannels that may be concerned and
 435          * do a validation on those.
 436          * The more information we have (info), the less scanning
 437          * will we have to do.
 438          */
 439         rc = for_each_subchannel(__s390_process_res_acc, res_data);
 440         if (css_slow_subchannels_exist())
 441                 rc = -EAGAIN;
 442         else if (rc != -EAGAIN)
 443                 rc = 0;
 444         return rc;
 445 }
 446
 447 static int
 448 __get_chpid_from_lir(void *data)
 449 {
 450         struct lir {
 451                 u8  iq;
 452                 u8  ic;
 453                 u16 sci;
 454                 /* incident-node descriptor */
 455                 u32 indesc[28];
 456                 /* attached-node descriptor */
 457                 u32 andesc[28];
 458                 /* incident-specific information */
 459                 u32 isinfo[28];
 460         } *lir;
 461
 462         lir = (struct lir*) data;
 463         if (!(lir->iq&0x80))
 464                 /* NULL link incident record */
 465                 return -EINVAL;
 466         if (!(lir->indesc[0]&0xc0000000))
 467                 /* node descriptor not valid */
 468                 return -EINVAL;
 469         if (!(lir->indesc[0]&0x10000000))
 470                 /* don't handle device-type nodes - FIXME */
 471                 return -EINVAL;
 472         /* Byte 3 contains the chpid. Could also be CTCA, but we don't care */
 473
 474         return (u16) (lir->indesc[0]&0x000000ff);
 475 }
 476
 477 int
 478 chsc_process_crw(void)
 479 {
 480         int chpid, ret;
 481         struct res_acc_data res_data;
 482         struct {
 483                 struct chsc_header request;
 484                 u32 reserved1;
 485                 u32 reserved2;
 486                 u32 reserved3;
 487                 struct chsc_header response;
 488                 u32 reserved4;
 489                 u8  flags;
 490                 u8  vf;         /* validity flags */
 491                 u8  rs;         /* reporting source */
 492                 u8  cc;         /* content code */
 493                 u16 fla;        /* full link address */
 494                 u16 rsid;       /* reporting source id */
 495                 u32 reserved5;
 496                 u32 reserved6;
 497                 u32 ccdf[96];   /* content-code dependent field */
 498                 /* ccdf has to be big enough for a link-incident record */
 499         } *sei_area;
 500
 501         if (!sei_page)
 502                 return 0;
 503         /*
 504          * build the chsc request block for store event information
 505          * and do the call
 506          * This function is only called by the machine check handler thread,
 507          * so we don't need locking for the sei_page.
 508          */
 509         sei_area = sei_page;
 510
 511         CIO_TRACE_EVENT( 2, "prcss");
 512         ret = 0;
 513         do {
 514                 int ccode, status;
 515                 struct device *dev;
 516                 memset(sei_area, 0, sizeof(*sei_area));
 517                 memset(&res_data, 0, sizeof(struct res_acc_data));
 518                 sei_area->request.length = 0x0010;
 519                 sei_area->request.code = 0x000e;
 520
 521                 ccode = chsc(sei_area);
 522                 if (ccode > 0)
 523                         return 0;
 524
 525                 switch (sei_area->response.code) {
 526                         /* for debug purposes, check for problems */
 527                 case 0x0001:
 528                         CIO_CRW_EVENT(4, "chsc_process_crw: event information "
 529                                         "successfully stored\n");
 530                         break; /* everything ok */
 531                 case 0x0002:
 532                         CIO_CRW_EVENT(2,
 533                                       "chsc_process_crw: invalid command!\n");
 534                         return 0;
 535                 case 0x0003:
 536                         CIO_CRW_EVENT(2, "chsc_process_crw: error in chsc "
 537                                       "request block!\n");
 538                         return 0;
 539                 case 0x0005:
 540                         CIO_CRW_EVENT(2, "chsc_process_crw: no event "
 541                                       "information stored\n");
 542                         return 0;
 543                 default:
 544                         CIO_CRW_EVENT(2, "chsc_process_crw: chsc response %d\n",
 545                                       sei_area->response.code);
 546                         return 0;
 547                 }
 548
 549                 /* Check if we might have lost some information. */
 550                 if (sei_area->flags & 0x40)
 551                         CIO_CRW_EVENT(2, "chsc_process_crw: Event information "
 552                                        "has been lost due to overflow!\n");
 553
 554                 if (sei_area->rs != 4) {
 555                         CIO_CRW_EVENT(2, "chsc_process_crw: reporting source "
 556                                       "(%04X) isn't a chpid!\n",
 557                                       sei_area->rsid);
 558                         continue;
 559                 }
 560
 561                 /* which kind of information was stored? */
 562                 switch (sei_area->cc) {
 563                 case 1: /* link incident*/
 564                         CIO_CRW_EVENT(4, "chsc_process_crw: "
 565                                       "channel subsystem reports link incident,"
 566                                       " reporting source is chpid %x\n",
 567                                       sei_area->rsid);
 568                         chpid = __get_chpid_from_lir(sei_area->ccdf);
 569                         if (chpid < 0)
 570                                 CIO_CRW_EVENT(4, "%s: Invalid LIR, skipping\n",
 571                                               __FUNCTION__);
 572                         else
 573                                 s390_set_chpid_offline(chpid);
 574                         break;
 575
 576                 case 2: /* i/o resource accessibiliy */
 577                         CIO_CRW_EVENT(4, "chsc_process_crw: "
 578                                       "channel subsystem reports some I/O "
 579                                       "devices may have become accessible\n");
 580                         pr_debug("Data received after sei: \n");
 581                         pr_debug("Validity flags: %x\n", sei_area->vf);
 582
 583                         /* allocate a new channel path structure, if needed */
 584                         status = get_chp_status(sei_area->rsid);
 585                         if (status < 0)
 586                                 new_channel_path(sei_area->rsid);
 587                         else if (!status)
 588                                 break;
 589                         dev = get_device(&css[0]->chps[sei_area->rsid]->dev);
 590                         res_data.chp = to_channelpath(dev);
 591                         pr_debug("chpid: %x", sei_area->rsid);
 592                         if ((sei_area->vf & 0xc0) != 0) {
 593                                 res_data.fla = sei_area->fla;
 594                                 if ((sei_area->vf & 0xc0) == 0xc0) {
 595                                         pr_debug(" full link addr: %x",
 596                                                  sei_area->fla);
 597                                         res_data.fla_mask = 0xffff;
 598                                 } else {
 599                                         pr_debug(" link addr: %x",
 600                                                  sei_area->fla);
 601                                         res_data.fla_mask = 0xff00;
 602                                 }
 603                         }
 604                         ret = s390_process_res_acc(&res_data);
 605                         pr_debug("\n\n");
 606                         put_device(dev);
 607                         break;
 608
 609                 default: /* other stuff */
 610                         CIO_CRW_EVENT(4, "chsc_process_crw: event %d\n",
 611                                       sei_area->cc);
 612                         break;
 613                 }
 614         } while (sei_area->flags & 0x80);
 615         return ret;
 616 }
 617
 618 static inline int
 619 __chp_add_new_sch(struct subchannel_id schid)
 620 {
 621         struct schib schib;
 622         int ret;
 623
 624         if (stsch(schid, &schib))
 625                 /* We're through */
 626                 return need_rescan ? -EAGAIN : -ENXIO;
 627
 628         /* Put it on the slow path. */
 629         ret = css_enqueue_subchannel_slow(schid);
 630         if (ret) {
 631                 css_clear_subchannel_slow_list();
 632                 need_rescan = 1;
 633                 return -EAGAIN;
 634         }
 635         return 0;
 636 }
 637
 638
 639 static int
 640 __chp_add(struct subchannel_id schid, void *data)
 641 {
 642         int i;
 643         struct channel_path *chp;
 644         struct subchannel *sch;
 645
 646         chp = (struct channel_path *)data;
 647         sch = get_subchannel_by_schid(schid);
 648         if (!sch)
 649                 /* Check if the subchannel is now available. */
 650                 return __chp_add_new_sch(schid);
 651         spin_lock_irq(&sch->lock);
 652         for (i=0; i<8; i++)
 653                 if (sch->schib.pmcw.chpid[i] == chp->id) {
 654                         if (stsch(sch->schid, &sch->schib) != 0) {
 655                                 /* Endgame. */
 656                                 spin_unlock(&sch->lock);
 657                                 return -ENXIO;
 658                         }
 659                         break;
 660                 }
 661         if (i==8) {
 662                 spin_unlock(&sch->lock);
 663                 return 0;
 664         }
 665         sch->lpm = ((sch->schib.pmcw.pim &
 666                      sch->schib.pmcw.pam &
 667                      sch->schib.pmcw.pom)
 668                     | 0x80 >> i) & sch->opm;
 669
 670         if (sch->driver && sch->driver->verify)
 671                 sch->driver->verify(&sch->dev);
 672
 673         spin_unlock_irq(&sch->lock);
 674         put_device(&sch->dev);
 675         return 0;
 676 }
 677
 678 static int
 679 chp_add(int chpid)
 680 {
 681         int rc;
 682         char dbf_txt[15];
 683         struct device *dev;
 684
 685         if (!get_chp_status(chpid))
 686                 return 0; /* no need to do the rest */
 687
 688         sprintf(dbf_txt, "cadd%x", chpid);
 689         CIO_TRACE_EVENT(2, dbf_txt);
 690
 691         dev = get_device(&css[0]->chps[chpid]->dev);
 692         rc = for_each_subchannel(__chp_add, to_channelpath(dev));
 693         if (css_slow_subchannels_exist())
 694                 rc = -EAGAIN;
 695         if (rc != -EAGAIN)
 696                 rc = 0;
 697         put_device(dev);
 698         return rc;
 699 }
 700
 701 /*
 702  * Handling of crw machine checks with channel path source.
 703  */
 704 int
 705 chp_process_crw(int chpid, int on)
 706 {
 707         if (on == 0) {
 708                 /* Path has gone. We use the link incident routine.*/
 709                 s390_set_chpid_offline(chpid);
 710                 return 0; /* De-register is async anyway. */
 711         }
 712         /*
 713          * Path has come. Allocate a new channel path structure,
 714          * if needed.
 715          */
 716         if (get_chp_status(chpid) < 0)
 717                 new_channel_path(chpid);
 718         /* Avoid the extra overhead in process_rec_acc. */
 719         return chp_add(chpid);
 720 }
 721
 722 static inline int
 723 __check_for_io_and_kill(struct subchannel *sch, int index)
 724 {
 725         int cc;
 726
 727         if (!device_is_online(sch))
 728                 /* cio could be doing I/O. */
 729                 return 0;
 730         cc = stsch(sch->schid, &sch->schib);
 731         if (cc)
 732                 return 0;
 733         if (sch->schib.scsw.actl && sch->schib.pmcw.lpum == (0x80 >> index)) {
 734                 device_set_waiting(sch);
 735                 return 1;
 736         }
 737         return 0;
 738 }
 739
 740 static inline void
 741 __s390_subchannel_vary_chpid(struct subchannel *sch, __u8 chpid, int on)
 742 {
 743         int chp, old_lpm;
 744         unsigned long flags;
 745
 746         if (!sch->ssd_info.valid)
 747                 return;
 748
 749         spin_lock_irqsave(&sch->lock, flags);
 750         old_lpm = sch->lpm;
 751         for (chp = 0; chp < 8; chp++) {
 752                 if (sch->ssd_info.chpid[chp] != chpid)
 753                         continue;
 754
 755                 if (on) {
 756                         sch->opm |= (0x80 >> chp);
 757                         sch->lpm |= (0x80 >> chp);
 758                         if (!old_lpm)
 759                                 device_trigger_reprobe(sch);
 760                         else if (sch->driver && sch->driver->verify)
 761                                 sch->driver->verify(&sch->dev);
 762                 } else {
 763                         sch->opm &= ~(0x80 >> chp);
 764                         sch->lpm &= ~(0x80 >> chp);
 765                         /*
 766                          * Give running I/O a grace period in which it
 767                          * can successfully terminate, even using the
 768                          * just varied off path. Then kill it.
 769                          */
 770                         if (!__check_for_io_and_kill(sch, chp) && !sch->lpm) {
 771                                 if (css_enqueue_subchannel_slow(sch->schid)) {
 772                                         css_clear_subchannel_slow_list();
 773                                         need_rescan = 1;
 774                                 }
 775                         } else if (sch->driver && sch->driver->verify)
 776                                 sch->driver->verify(&sch->dev);
 777                 }
 778                 break;
 779         }
 780         spin_unlock_irqrestore(&sch->lock, flags);
 781 }
 782
 783 static int
 784 s390_subchannel_vary_chpid_off(struct device *dev, void *data)
 785 {
 786         struct subchannel *sch;
 787         __u8 *chpid;
 788
 789         sch = to_subchannel(dev);
 790         chpid = data;
 791
 792         __s390_subchannel_vary_chpid(sch, *chpid, 0);
 793         return 0;
 794 }
 795
 796 static int
 797 s390_subchannel_vary_chpid_on(struct device *dev, void *data)
 798 {
 799         struct subchannel *sch;
 800         __u8 *chpid;
 801
 802         sch = to_subchannel(dev);
 803         chpid = data;
 804
 805         __s390_subchannel_vary_chpid(sch, *chpid, 1);
 806         return 0;
 807 }
 808
 809 static int
 810 __s390_vary_chpid_on(struct subchannel_id schid, void *data)
 811 {
 812         struct schib schib;
 813         struct subchannel *sch;
 814
 815         sch = get_subchannel_by_schid(schid);
 816         if (sch) {
 817                 put_device(&sch->dev);
 818                 return 0;
 819         }
 820         if (stsch_err(schid, &schib))
 821                 /* We're through */
 822                 return -ENXIO;
 823         /* Put it on the slow path. */
 824         if (css_enqueue_subchannel_slow(schid)) {
 825                 css_clear_subchannel_slow_list();
 826                 need_rescan = 1;
 827                 return -EAGAIN;
 828         }
 829         return 0;
 830 }
 831
 832 /*
 833  * Function: s390_vary_chpid
 834  * Varies the specified chpid online or offline
 835  */
 836 static int
 837 s390_vary_chpid( __u8 chpid, int on)
 838 {
 839         char dbf_text[15];
 840         int status;
 841
 842         sprintf(dbf_text, on?"varyon%x":"varyoff%x", chpid);
 843         CIO_TRACE_EVENT( 2, dbf_text);
 844
 845         status = get_chp_status(chpid);
 846         if (status < 0) {
 847                 printk(KERN_ERR "Can't vary unknown chpid %02X\n", chpid);
 848                 return -EINVAL;
 849         }
 850
 851         if (!on && !status) {
 852                 printk(KERN_ERR "chpid %x is already offline\n", chpid);
 853                 return -EINVAL;
 854         }
 855
 856         set_chp_logically_online(chpid, on);
 857
 858         /*
 859          * Redo PathVerification on the devices the chpid connects to
 860          */
 861
 862         bus_for_each_dev(&css_bus_type, NULL, &chpid, on ?
 863                          s390_subchannel_vary_chpid_on :
 864                          s390_subchannel_vary_chpid_off);
 865         if (on)
 866                 /* Scan for new devices on varied on path. */
 867                 for_each_subchannel(__s390_vary_chpid_on, NULL);
 868         if (need_rescan || css_slow_subchannels_exist())
 869                 queue_work(slow_path_wq, &slow_path_work);
 870         return 0;
 871 }
 872
 873 /*
 874  * Channel measurement related functions
 875  */
 876 static ssize_t
 877 chp_measurement_chars_read(struct kobject *kobj, char *buf, loff_t off,
 878                            size_t count)
 879 {
 880         struct channel_path *chp;
 881         unsigned int size;
 882
 883         chp = to_channelpath(container_of(kobj, struct device, kobj));
 884         if (!chp->cmg_chars)
 885                 return 0;
 886
 887         size = sizeof(struct cmg_chars);
 888
 889         if (off > size)
 890                 return 0;
 891         if (off + count > size)
 892                 count = size - off;
 893         memcpy(buf, chp->cmg_chars + off, count);
 894         return count;
 895 }
 896
 897 static struct bin_attribute chp_measurement_chars_attr = {
 898         .attr = {
 899                 .name = "measurement_chars",
 900                 .mode = S_IRUSR,
 901                 .owner = THIS_MODULE,
 902         },
 903         .size = sizeof(struct cmg_chars),
 904         .read = chp_measurement_chars_read,
 905 };
 906
 907 static void
 908 chp_measurement_copy_block(struct cmg_entry *buf,
 909                            struct channel_subsystem *css, int chpid)
 910 {
 911         void *area;
 912         struct cmg_entry *entry, reference_buf;
 913         int idx;
 914
 915         if (chpid < 128) {
 916                 area = css->cub_addr1;
 917                 idx = chpid;
 918         } else {
 919                 area = css->cub_addr2;
 920                 idx = chpid - 128;
 921         }
 922         entry = area + (idx * sizeof(struct cmg_entry));
 923         do {
 924                 memcpy(buf, entry, sizeof(*entry));
 925                 memcpy(&reference_buf, entry, sizeof(*entry));
 926         } while (reference_buf.values[0] != buf->values[0]);
 927 }
 928
 929 static ssize_t
 930 chp_measurement_read(struct kobject *kobj, char *buf, loff_t off, size_t count)
 931 {
 932         struct channel_path *chp;
 933         struct channel_subsystem *css;
 934         unsigned int size;
 935
 936         chp = to_channelpath(container_of(kobj, struct device, kobj));
 937         css = to_css(chp->dev.parent);
 938
 939         size = sizeof(struct cmg_chars);
 940
 941         /* Only allow single reads. */
 942         if (off || count < size)
 943                 return 0;
 944         chp_measurement_copy_block((struct cmg_entry *)buf, css, chp->id);
 945         return count;
 946 }
 947
 948 static struct bin_attribute chp_measurement_attr = {
 949         .attr = {
 950                 .name = "measurement",
 951                 .mode = S_IRUSR,
 952                 .owner = THIS_MODULE,
 953         },
 954         .size = sizeof(struct cmg_entry),
 955         .read = chp_measurement_read,
 956 };
 957
 958 static void
 959 chsc_remove_chp_cmg_attr(struct channel_path *chp)
 960 {
 961         sysfs_remove_bin_file(&chp->dev.kobj, &chp_measurement_chars_attr);
 962         sysfs_remove_bin_file(&chp->dev.kobj, &chp_measurement_attr);
 963 }
 964
 965 static int
 966 chsc_add_chp_cmg_attr(struct channel_path *chp)
 967 {
 968         int ret;
 969
 970         ret = sysfs_create_bin_file(&chp->dev.kobj,
 971                                     &chp_measurement_chars_attr);
 972         if (ret)
 973                 return ret;
 974         ret = sysfs_create_bin_file(&chp->dev.kobj, &chp_measurement_attr);
 975         if (ret)
 976                 sysfs_remove_bin_file(&chp->dev.kobj,
 977                                       &chp_measurement_chars_attr);
 978         return ret;
 979 }
 980
 981 static void
 982 chsc_remove_cmg_attr(struct channel_subsystem *css)
 983 {
 984         int i;
 985
 986         for (i = 0; i <= __MAX_CHPID; i++) {
 987                 if (!css->chps[i])
 988                         continue;
 989                 chsc_remove_chp_cmg_attr(css->chps[i]);
 990         }
 991 }
 992
 993 static int
 994 chsc_add_cmg_attr(struct channel_subsystem *css)
 995 {
 996         int i, ret;
 997
 998         ret = 0;
 999         for (i = 0; i <= __MAX_CHPID; i++) {
1000                 if (!css->chps[i])
1001                         continue;
1002                 ret = chsc_add_chp_cmg_attr(css->chps[i]);
1003                 if (ret)
1004                         goto cleanup;
1005         }
1006         return ret;
1007 cleanup:
1008         for (--i; i >= 0; i--) {
1009                 if (!css->chps[i])
1010                         continue;
1011                 chsc_remove_chp_cmg_attr(css->chps[i]);
1012         }
1013         return ret;
1014 }
1015
1016
1017 static int
1018 __chsc_do_secm(struct channel_subsystem *css, int enable, void *page)
1019 {
1020         struct {
1021                 struct chsc_header request;
1022                 u32 operation_code : 2;
1023                 u32 : 30;
1024                 u32 key : 4;
1025                 u32 : 28;
1026                 u32 zeroes1;
1027                 u32 cub_addr1;
1028                 u32 zeroes2;
1029                 u32 cub_addr2;
1030                 u32 reserved[13];
1031                 struct chsc_header response;
1032                 u32 status : 8;
1033                 u32 : 4;
1034                 u32 fmt : 4;
1035                 u32 : 16;
1036         } *secm_area;
1037         int ret, ccode;
1038
1039         secm_area = page;
1040         secm_area->request.length = 0x0050;
1041         secm_area->request.code = 0x0016;
1042
1043         secm_area->key = PAGE_DEFAULT_KEY;
1044         secm_area->cub_addr1 = (u64)(unsigned long)css->cub_addr1;
1045         secm_area->cub_addr2 = (u64)(unsigned long)css->cub_addr2;
1046
1047         secm_area->operation_code = enable ? 0 : 1;
1048
1049         ccode = chsc(secm_area);
1050         if (ccode > 0)
1051                 return (ccode == 3) ? -ENODEV : -EBUSY;
1052
1053         switch (secm_area->response.code) {
1054         case 0x0001: /* Success. */
1055                 ret = 0;
1056                 break;
1057         case 0x0003: /* Invalid block. */
1058         case 0x0007: /* Invalid format. */
1059         case 0x0008: /* Other invalid block. */
1060                 CIO_CRW_EVENT(2, "Error in chsc request block!\n");
1061                 ret = -EINVAL;
1062                 break;
1063         case 0x0004: /* Command not provided in model. */
1064                 CIO_CRW_EVENT(2, "Model does not provide secm\n");
1065                 ret = -EOPNOTSUPP;
1066                 break;
1067         case 0x0102: /* cub adresses incorrect */
1068                 CIO_CRW_EVENT(2, "Invalid addresses in chsc request block\n");
1069                 ret = -EINVAL;
1070                 break;
1071         case 0x0103: /* key error */
1072                 CIO_CRW_EVENT(2, "Access key error in secm\n");
1073                 ret = -EINVAL;
1074                 break;
1075         case 0x0105: /* error while starting */
1076                 CIO_CRW_EVENT(2, "Error while starting channel measurement\n");
1077                 ret = -EIO;
1078                 break;
1079         default:
1080                 CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
1081                               secm_area->response.code);
1082                 ret = -EIO;
1083         }
1084         return ret;
1085 }
1086
1087 int
1088 chsc_secm(struct channel_subsystem *css, int enable)
1089 {
1090         void  *secm_area;
1091         int ret;
1092
1093         secm_area = (void *)get_zeroed_page(GFP_KERNEL |  GFP_DMA);
1094         if (!secm_area)
1095                 return -ENOMEM;
1096
1097         mutex_lock(&css->mutex);
1098         if (enable && !css->cm_enabled) {
1099                 css->cub_addr1 = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1100                 css->cub_addr2 = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1101                 if (!css->cub_addr1 || !css->cub_addr2) {
1102                         free_page((unsigned long)css->cub_addr1);
1103                         free_page((unsigned long)css->cub_addr2);
1104                         free_page((unsigned long)secm_area);
1105                         mutex_unlock(&css->mutex);
1106                         return -ENOMEM;
1107                 }
1108         }
1109         ret = __chsc_do_secm(css, enable, secm_area);
1110         if (!ret) {
1111                 css->cm_enabled = enable;
1112                 if (css->cm_enabled) {
1113                         ret = chsc_add_cmg_attr(css);
1114                         if (ret) {
1115                                 memset(secm_area, 0, PAGE_SIZE);
1116                                 __chsc_do_secm(css, 0, secm_area);
1117                                 css->cm_enabled = 0;
1118                         }
1119                 } else
1120                         chsc_remove_cmg_attr(css);
1121         }
1122         if (enable && !css->cm_enabled) {
1123                 free_page((unsigned long)css->cub_addr1);
1124                 free_page((unsigned long)css->cub_addr2);
1125         }
1126         mutex_unlock(&css->mutex);
1127         free_page((unsigned long)secm_area);
1128         return ret;
1129 }
1130
1131 /*
1132  * Files for the channel path entries.
1133  */
1134 static ssize_t
1135 chp_status_show(struct device *dev, struct device_attribute *attr, char *buf)
1136 {
1137         struct channel_path *chp = container_of(dev, struct channel_path, dev);
1138
1139         if (!chp)
1140                 return 0;
1141         return (get_chp_status(chp->id) ? sprintf(buf, "online\n") :
1142                 sprintf(buf, "offline\n"));
1143 }
1144
1145 static ssize_t
1146 chp_status_write(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
1147 {
1148         struct channel_path *cp = container_of(dev, struct channel_path, dev);
1149         char cmd[10];
1150         int num_args;
1151         int error;
1152
1153         num_args = sscanf(buf, "%5s", cmd);
1154         if (!num_args)
1155                 return count;
1156
1157         if (!strnicmp(cmd, "on", 2))
1158                 error = s390_vary_chpid(cp->id, 1);
1159         else if (!strnicmp(cmd, "off", 3))
1160                 error = s390_vary_chpid(cp->id, 0);
1161         else
1162                 error = -EINVAL;
1163
1164         return error < 0 ? error : count;
1165
1166 }
1167
1168 static DEVICE_ATTR(status, 0644, chp_status_show, chp_status_write);
1169
1170 static ssize_t
1171 chp_type_show(struct device *dev, struct device_attribute *attr, char *buf)
1172 {
1173         struct channel_path *chp = container_of(dev, struct channel_path, dev);
1174
1175         if (!chp)
1176                 return 0;
1177         return sprintf(buf, "%x\n", chp->desc.desc);
1178 }
1179
1180 static DEVICE_ATTR(type, 0444, chp_type_show, NULL);
1181
1182 static ssize_t
1183 chp_cmg_show(struct device *dev, struct device_attribute *attr, char *buf)
1184 {
1185         struct channel_path *chp = to_channelpath(dev);
1186
1187         if (!chp)
1188                 return 0;
1189         if (chp->cmg == -1) /* channel measurements not available */
1190                 return sprintf(buf, "unknown\n");
1191         return sprintf(buf, "%x\n", chp->cmg);
1192 }
1193
1194 static DEVICE_ATTR(cmg, 0444, chp_cmg_show, NULL);
1195
1196 static ssize_t
1197 chp_shared_show(struct device *dev, struct device_attribute *attr, char *buf)
1198 {
1199         struct channel_path *chp = to_channelpath(dev);
1200
1201         if (!chp)
1202                 return 0;
1203         if (chp->shared == -1) /* channel measurements not available */
1204                 return sprintf(buf, "unknown\n");
1205         return sprintf(buf, "%x\n", chp->shared);
1206 }
1207
1208 static DEVICE_ATTR(shared, 0444, chp_shared_show, NULL);
1209
1210 static struct attribute * chp_attrs[] = {
1211         &dev_attr_status.attr,
1212         &dev_attr_type.attr,
1213         &dev_attr_cmg.attr,
1214         &dev_attr_shared.attr,
1215         NULL,
1216 };
1217
1218 static struct attribute_group chp_attr_group = {
1219         .attrs = chp_attrs,
1220 };
1221
1222 static void
1223 chp_release(struct device *dev)
1224 {
1225         struct channel_path *cp;
1226
1227         cp = container_of(dev, struct channel_path, dev);
1228         kfree(cp);
1229 }
1230
1231 static int
1232 chsc_determine_channel_path_description(int chpid,
1233                                         struct channel_path_desc *desc)
1234 {
1235         int ccode, ret;
1236
1237         struct {
1238                 struct chsc_header request;
1239                 u32 : 24;
1240                 u32 first_chpid : 8;
1241                 u32 : 24;
1242                 u32 last_chpid : 8;
1243                 u32 zeroes1;
1244                 struct chsc_header response;
1245                 u32 zeroes2;
1246                 struct channel_path_desc desc;
1247         } *scpd_area;
1248
1249         scpd_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1250         if (!scpd_area)
1251                 return -ENOMEM;
1252
1253         scpd_area->request.length = 0x0010;
1254         scpd_area->request.code = 0x0002;
1255
1256         scpd_area->first_chpid = chpid;
1257         scpd_area->last_chpid = chpid;
1258
1259         ccode = chsc(scpd_area);
1260         if (ccode > 0) {
1261                 ret = (ccode == 3) ? -ENODEV : -EBUSY;
1262                 goto out;
1263         }
1264
1265         switch (scpd_area->response.code) {
1266         case 0x0001: /* Success. */
1267                 memcpy(desc, &scpd_area->desc,
1268                        sizeof(struct channel_path_desc));
1269                 ret = 0;
1270                 break;
1271         case 0x0003: /* Invalid block. */
1272         case 0x0007: /* Invalid format. */
1273         case 0x0008: /* Other invalid block. */
1274                 CIO_CRW_EVENT(2, "Error in chsc request block!\n");
1275                 ret = -EINVAL;
1276                 break;
1277         case 0x0004: /* Command not provided in model. */
1278                 CIO_CRW_EVENT(2, "Model does not provide scpd\n");
1279                 ret = -EOPNOTSUPP;
1280                 break;
1281         default:
1282                 CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
1283                               scpd_area->response.code);
1284                 ret = -EIO;
1285         }
1286 out:
1287         free_page((unsigned long)scpd_area);
1288         return ret;
1289 }
1290
1291 static void
1292 chsc_initialize_cmg_chars(struct channel_path *chp, u8 cmcv,
1293                           struct cmg_chars *chars)
1294 {
1295         switch (chp->cmg) {
1296         case 2:
1297         case 3:
1298                 chp->cmg_chars = kmalloc(sizeof(struct cmg_chars),
1299                                          GFP_KERNEL);
1300                 if (chp->cmg_chars) {
1301                         int i, mask;
1302                         struct cmg_chars *cmg_chars;
1303
1304                         cmg_chars = chp->cmg_chars;
1305                         for (i = 0; i < NR_MEASUREMENT_CHARS; i++) {
1306                                 mask = 0x80 >> (i + 3);
1307                                 if (cmcv & mask)
1308                                         cmg_chars->values[i] = chars->values[i];
1309                                 else
1310                                         cmg_chars->values[i] = 0;
1311                         }
1312                 }
1313                 break;
1314         default:
1315                 /* No cmg-dependent data. */
1316                 break;
1317         }
1318 }
1319
1320 static int
1321 chsc_get_channel_measurement_chars(struct channel_path *chp)
1322 {
1323         int ccode, ret;
1324
1325         struct {
1326                 struct chsc_header request;
1327                 u32 : 24;
1328                 u32 first_chpid : 8;
1329                 u32 : 24;
1330                 u32 last_chpid : 8;
1331                 u32 zeroes1;
1332                 struct chsc_header response;
1333                 u32 zeroes2;
1334                 u32 not_valid : 1;
1335                 u32 shared : 1;
1336                 u32 : 22;
1337                 u32 chpid : 8;
1338                 u32 cmcv : 5;
1339                 u32 : 11;
1340                 u32 cmgq : 8;
1341                 u32 cmg : 8;
1342                 u32 zeroes3;
1343                 u32 data[NR_MEASUREMENT_CHARS];
1344         } *scmc_area;
1345
1346         scmc_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1347         if (!scmc_area)
1348                 return -ENOMEM;
1349
1350         scmc_area->request.length = 0x0010;
1351         scmc_area->request.code = 0x0022;
1352
1353         scmc_area->first_chpid = chp->id;
1354         scmc_area->last_chpid = chp->id;
1355
1356         ccode = chsc(scmc_area);
1357         if (ccode > 0) {
1358                 ret = (ccode == 3) ? -ENODEV : -EBUSY;
1359                 goto out;
1360         }
1361
1362         switch (scmc_area->response.code) {
1363         case 0x0001: /* Success. */
1364                 if (!scmc_area->not_valid) {
1365                         chp->cmg = scmc_area->cmg;
1366                         chp->shared = scmc_area->shared;
1367                         chsc_initialize_cmg_chars(chp, scmc_area->cmcv,
1368                                                   (struct cmg_chars *)
1369                                                   &scmc_area->data);
1370                 } else {
1371                         chp->cmg = -1;
1372                         chp->shared = -1;
1373                 }
1374                 ret = 0;
1375                 break;
1376         case 0x0003: /* Invalid block. */
1377         case 0x0007: /* Invalid format. */
1378         case 0x0008: /* Invalid bit combination. */
1379                 CIO_CRW_EVENT(2, "Error in chsc request block!\n");
1380                 ret = -EINVAL;
1381                 break;
1382         case 0x0004: /* Command not provided. */
1383                 CIO_CRW_EVENT(2, "Model does not provide scmc\n");
1384                 ret = -EOPNOTSUPP;
1385                 break;
1386         default:
1387                 CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
1388                               scmc_area->response.code);
1389                 ret = -EIO;
1390         }
1391 out:
1392         free_page((unsigned long)scmc_area);
1393         return ret;
1394 }
1395
1396 /*
1397  * Entries for chpids on the system bus.
1398  * This replaces /proc/chpids.
1399  */
1400 static int
1401 new_channel_path(int chpid)
1402 {
1403         struct channel_path *chp;
1404         int ret;
1405
1406         chp = kzalloc(sizeof(struct channel_path), GFP_KERNEL);
1407         if (!chp)
1408                 return -ENOMEM;
1409
1410         /* fill in status, etc. */
1411         chp->id = chpid;
1412         chp->state = 1;
1413         chp->dev = (struct device) {
1414                 .parent  = &css[0]->device,
1415                 .release = chp_release,
1416         };
1417         snprintf(chp->dev.bus_id, BUS_ID_SIZE, "chp0.%x", chpid);
1418
1419         /* Obtain channel path description and fill it in. */
1420         ret = chsc_determine_channel_path_description(chpid, &chp->desc);
1421         if (ret)
1422                 goto out_free;
1423         /* Get channel-measurement characteristics. */
1424         if (css_characteristics_avail && css_chsc_characteristics.scmc
1425             && css_chsc_characteristics.secm) {
1426                 ret = chsc_get_channel_measurement_chars(chp);
1427                 if (ret)
1428                         goto out_free;
1429         } else {
1430                 static int msg_done;
1431
1432                 if (!msg_done) {
1433                         printk(KERN_WARNING "cio: Channel measurements not "
1434                                "available, continuing.\n");
1435                         msg_done = 1;
1436                 }
1437                 chp->cmg = -1;
1438         }
1439
1440         /* make it known to the system */
1441         ret = device_register(&chp->dev);
1442         if (ret) {
1443                 printk(KERN_WARNING "%s: could not register %02x\n",
1444                        __func__, chpid);
1445                 goto out_free;
1446         }
1447         ret = sysfs_create_group(&chp->dev.kobj, &chp_attr_group);
1448         if (ret) {
1449                 device_unregister(&chp->dev);
1450                 goto out_free;
1451         }
1452         mutex_lock(&css[0]->mutex);
1453         if (css[0]->cm_enabled) {
1454                 ret = chsc_add_chp_cmg_attr(chp);
1455                 if (ret) {
1456                         sysfs_remove_group(&chp->dev.kobj, &chp_attr_group);
1457                         device_unregister(&chp->dev);
1458                         mutex_unlock(&css[0]->mutex);
1459                         goto out_free;
1460                 }
1461         }
1462         css[0]->chps[chpid] = chp;
1463         mutex_unlock(&css[0]->mutex);
1464         return ret;
1465 out_free:
1466         kfree(chp);
1467         return ret;
1468 }
1469
1470 void *
1471 chsc_get_chp_desc(struct subchannel *sch, int chp_no)
1472 {
1473         struct channel_path *chp;
1474         struct channel_path_desc *desc;
1475
1476         chp = css[0]->chps[sch->schib.pmcw.chpid[chp_no]];
1477         if (!chp)
1478                 return NULL;
1479         desc = kmalloc(sizeof(struct channel_path_desc), GFP_KERNEL);
1480         if (!desc)
1481                 return NULL;
1482         memcpy(desc, &chp->desc, sizeof(struct channel_path_desc));
1483         return desc;
1484 }
1485
1486
1487 static int __init
1488 chsc_alloc_sei_area(void)
1489 {
1490         sei_page = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1491         if (!sei_page)
1492                 printk(KERN_WARNING"Can't allocate page for processing of " \
1493                        "chsc machine checks!\n");
1494         return (sei_page ? 0 : -ENOMEM);
1495 }
1496
1497 int __init
1498 chsc_enable_facility(int operation_code)
1499 {
1500         int ret;
1501         struct {
1502                 struct chsc_header request;
1503                 u8 reserved1:4;
1504                 u8 format:4;
1505                 u8 reserved2;
1506                 u16 operation_code;
1507                 u32 reserved3;
1508                 u32 reserved4;
1509                 u32 operation_data_area[252];
1510                 struct chsc_header response;
1511                 u32 reserved5:4;
1512                 u32 format2:4;
1513                 u32 reserved6:24;
1514         } *sda_area;
1515
1516         sda_area = (void *)get_zeroed_page(GFP_KERNEL|GFP_DMA);
1517         if (!sda_area)
1518                 return -ENOMEM;
1519         sda_area->request.length = 0x0400;
1520         sda_area->request.code = 0x0031;
1521         sda_area->operation_code = operation_code;
1522
1523         ret = chsc(sda_area);
1524         if (ret > 0) {
1525                 ret = (ret == 3) ? -ENODEV : -EBUSY;
1526                 goto out;
1527         }
1528         switch (sda_area->response.code) {
1529         case 0x0001: /* everything ok */
1530                 ret = 0;
1531                 break;
1532         case 0x0003: /* invalid request block */
1533         case 0x0007:
1534                 ret = -EINVAL;
1535                 break;
1536         case 0x0004: /* command not provided */
1537         case 0x0101: /* facility not provided */
1538                 ret = -EOPNOTSUPP;
1539                 break;
1540         default: /* something went wrong */
1541                 ret = -EIO;
1542         }
1543  out:
1544         free_page((unsigned long)sda_area);
1545         return ret;
1546 }
1547
1548 subsys_initcall(chsc_alloc_sei_area);
1549
1550 struct css_general_char css_general_characteristics;
1551 struct css_chsc_char css_chsc_characteristics;
1552
1553 int __init
1554 chsc_determine_css_characteristics(void)
1555 {
1556         int result;
1557         struct {
1558                 struct chsc_header request;
1559                 u32 reserved1;
1560                 u32 reserved2;
1561                 u32 reserved3;
1562                 struct chsc_header response;
1563                 u32 reserved4;
1564                 u32 general_char[510];
1565                 u32 chsc_char[518];
1566         } *scsc_area;
1567
1568         scsc_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1569         if (!scsc_area) {
1570                 printk(KERN_WARNING"cio: Was not able to determine available" \
1571                        "CHSCs due to no memory.\n");
1572                 return -ENOMEM;
1573         }
1574
1575         scsc_area->request.length = 0x0010;
1576         scsc_area->request.code = 0x0010;
1577
1578         result = chsc(scsc_area);
1579         if (result) {
1580                 printk(KERN_WARNING"cio: Was not able to determine " \
1581                        "available CHSCs, cc=%i.\n", result);
1582                 result = -EIO;
1583                 goto exit;
1584         }
1585
1586         if (scsc_area->response.code != 1) {
1587                 printk(KERN_WARNING"cio: Was not able to determine " \
1588                        "available CHSCs.\n");
1589                 result = -EIO;
1590                 goto exit;
1591         }
1592         memcpy(&css_general_characteristics, scsc_area->general_char,
1593                sizeof(css_general_characteristics));
1594         memcpy(&css_chsc_characteristics, scsc_area->chsc_char,
1595                sizeof(css_chsc_characteristics));
1596 exit:
1597         free_page ((unsigned long) scsc_area);
1598         return result;
1599 }
1600
1601 EXPORT_SYMBOL_GPL(css_general_characteristics);
1602 EXPORT_SYMBOL_GPL(css_chsc_characteristics);