err.no 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/slab.h>
  14 #include <linux/init.h>
  15 #include <linux/device.h>
  16
  17 #include <asm/cio.h>
  18
  19 #include "css.h"
  20 #include "cio.h"
  21 #include "cio_debug.h"
  22 #include "ioasm.h"
  23 #include "chpid.h"
  24 #include "chp.h"
  25 #include "chsc.h"
  26
  27 static void *sei_page;
  28
  29 /* FIXME: this is _always_ called for every subchannel. shouldn't we
  30  *        process more than one at a time? */
  31 static int
  32 chsc_get_sch_desc_irq(struct subchannel *sch, void *page)
  33 {
  34         int ccode, j;
  35
  36         struct {
  37                 struct chsc_header request;
  38                 u16 reserved1a:10;
  39                 u16 ssid:2;
  40                 u16 reserved1b:4;
  41                 u16 f_sch;        /* first subchannel */
  42                 u16 reserved2;
  43                 u16 l_sch;        /* last subchannel */
  44                 u32 reserved3;
  45                 struct chsc_header response;
  46                 u32 reserved4;
  47                 u8 sch_valid : 1;
  48                 u8 dev_valid : 1;
  49                 u8 st        : 3; /* subchannel type */
  50                 u8 zeroes    : 3;
  51                 u8  unit_addr;    /* unit address */
  52                 u16 devno;        /* device number */
  53                 u8 path_mask;
  54                 u8 fla_valid_mask;
  55                 u16 sch;          /* subchannel */
  56                 u8 chpid[8];      /* chpids 0-7 */
  57                 u16 fla[8];       /* full link addresses 0-7 */
  58         } __attribute__ ((packed)) *ssd_area;
  59
  60         ssd_area = page;
  61
  62         ssd_area->request.length = 0x0010;
  63         ssd_area->request.code = 0x0004;
  64
  65         ssd_area->ssid = sch->schid.ssid;
  66         ssd_area->f_sch = sch->schid.sch_no;
  67         ssd_area->l_sch = sch->schid.sch_no;
  68
  69         ccode = chsc(ssd_area);
  70         if (ccode > 0) {
  71                 pr_debug("chsc returned with ccode = %d\n", ccode);
  72                 return (ccode == 3) ? -ENODEV : -EBUSY;
  73         }
  74
  75         switch (ssd_area->response.code) {
  76         case 0x0001: /* everything ok */
  77                 break;
  78         case 0x0002:
  79                 CIO_CRW_EVENT(2, "Invalid command!\n");
  80                 return -EINVAL;
  81         case 0x0003:
  82                 CIO_CRW_EVENT(2, "Error in chsc request block!\n");
  83                 return -EINVAL;
  84         case 0x0004:
  85                 CIO_CRW_EVENT(2, "Model does not provide ssd\n");
  86                 return -EOPNOTSUPP;
  87         default:
  88                 CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
  89                               ssd_area->response.code);
  90                 return -EIO;
  91         }
  92
  93         /*
  94          * ssd_area->st stores the type of the detected
  95          * subchannel, with the following definitions:
  96          *
  97          * 0: I/O subchannel:     All fields have meaning
  98          * 1: CHSC subchannel:    Only sch_val, st and sch
  99          *                        have meaning
 100          * 2: Message subchannel: All fields except unit_addr
 101          *                        have meaning
 102          * 3: ADM subchannel:     Only sch_val, st and sch
 103          *                        have meaning
 104          *
 105          * Other types are currently undefined.
 106          */
 107         if (ssd_area->st > 3) { /* uhm, that looks strange... */
 108                 CIO_CRW_EVENT(0, "Strange subchannel type %d"
 109                               " for sch 0.%x.%04x\n", ssd_area->st,
 110                               sch->schid.ssid, sch->schid.sch_no);
 111                 /*
 112                  * There may have been a new subchannel type defined in the
 113                  * time since this code was written; since we don't know which
 114                  * fields have meaning and what to do with it we just jump out
 115                  */
 116                 return 0;
 117         } else {
 118                 const char *type[4] = {"I/O", "chsc", "message", "ADM"};
 119                 CIO_CRW_EVENT(6, "ssd: sch 0.%x.%04x is %s subchannel\n",
 120                               sch->schid.ssid, sch->schid.sch_no,
 121                               type[ssd_area->st]);
 122
 123                 sch->ssd_info.valid = 1;
 124                 sch->ssd_info.type = ssd_area->st;
 125         }
 126
 127         if (ssd_area->st == 0 || ssd_area->st == 2) {
 128                 for (j = 0; j < 8; j++) {
 129                         if (!((0x80 >> j) & ssd_area->path_mask &
 130                               ssd_area->fla_valid_mask))
 131                                 continue;
 132                         sch->ssd_info.chpid[j] = ssd_area->chpid[j];
 133                         sch->ssd_info.fla[j]   = ssd_area->fla[j];
 134                 }
 135         }
 136         return 0;
 137 }
 138
 139 int
 140 css_get_ssd_info(struct subchannel *sch)
 141 {
 142         int ret;
 143         void *page;
 144
 145         page = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
 146         if (!page)
 147                 return -ENOMEM;
 148         spin_lock_irq(sch->lock);
 149         ret = chsc_get_sch_desc_irq(sch, page);
 150         if (ret) {
 151                 static int cio_chsc_err_msg;
 152
 153                 if (!cio_chsc_err_msg) {
 154                         printk(KERN_ERR
 155                                "chsc_get_sch_descriptions:"
 156                                " Error %d while doing chsc; "
 157                                "processing some machine checks may "
 158                                "not work\n", ret);
 159                         cio_chsc_err_msg = 1;
 160                 }
 161         }
 162         spin_unlock_irq(sch->lock);
 163         free_page((unsigned long)page);
 164         if (!ret) {
 165                 int j, mask;
 166                 struct chp_id chpid;
 167
 168                 chp_id_init(&chpid);
 169                 /* Allocate channel path structures, if needed. */
 170                 for (j = 0; j < 8; j++) {
 171                         mask = 0x80 >> j;
 172                         chpid.id = sch->ssd_info.chpid[j];
 173                         if ((sch->schib.pmcw.pim & mask) &&
 174                             !chp_is_registered(chpid))
 175                                 chp_new(chpid);
 176                 }
 177         }
 178         return ret;
 179 }
 180
 181 static int
 182 s390_subchannel_remove_chpid(struct device *dev, void *data)
 183 {
 184         int j;
 185         int mask;
 186         struct subchannel *sch;
 187         struct chp_id *chpid;
 188         struct schib schib;
 189
 190         sch = to_subchannel(dev);
 191         chpid = data;
 192         for (j = 0; j < 8; j++) {
 193                 mask = 0x80 >> j;
 194                 if ((sch->schib.pmcw.pim & mask) &&
 195                     (sch->schib.pmcw.chpid[j] == chpid->id))
 196                         break;
 197         }
 198         if (j >= 8)
 199                 return 0;
 200
 201         spin_lock_irq(sch->lock);
 202
 203         stsch(sch->schid, &schib);
 204         if (!schib.pmcw.dnv)
 205                 goto out_unreg;
 206         memcpy(&sch->schib, &schib, sizeof(struct schib));
 207         /* Check for single path devices. */
 208         if (sch->schib.pmcw.pim == 0x80)
 209                 goto out_unreg;
 210
 211         if ((sch->schib.scsw.actl & SCSW_ACTL_DEVACT) &&
 212             (sch->schib.scsw.actl & SCSW_ACTL_SCHACT) &&
 213             (sch->schib.pmcw.lpum == mask)) {
 214                 int cc;
 215
 216                 cc = cio_clear(sch);
 217                 if (cc == -ENODEV)
 218                         goto out_unreg;
 219                 /* Request retry of internal operation. */
 220                 device_set_intretry(sch);
 221                 /* Call handler. */
 222                 if (sch->driver && sch->driver->termination)
 223                         sch->driver->termination(&sch->dev);
 224                 goto out_unlock;
 225         }
 226
 227         /* trigger path verification. */
 228         if (sch->driver && sch->driver->verify)
 229                 sch->driver->verify(&sch->dev);
 230         else if (sch->lpm == mask)
 231                 goto out_unreg;
 232 out_unlock:
 233         spin_unlock_irq(sch->lock);
 234         return 0;
 235 out_unreg:
 236         spin_unlock_irq(sch->lock);
 237         sch->lpm = 0;
 238         if (css_enqueue_subchannel_slow(sch->schid)) {
 239                 css_clear_subchannel_slow_list();
 240                 need_rescan = 1;
 241         }
 242         return 0;
 243 }
 244
 245 void chsc_chp_offline(struct chp_id chpid)
 246 {
 247         char dbf_txt[15];
 248
 249         sprintf(dbf_txt, "chpr%x.%02x", chpid.cssid, chpid.id);
 250         CIO_TRACE_EVENT(2, dbf_txt);
 251
 252         if (chp_get_status(chpid) <= 0)
 253                 return;
 254         bus_for_each_dev(&css_bus_type, NULL, &chpid,
 255                          s390_subchannel_remove_chpid);
 256
 257         if (need_rescan || css_slow_subchannels_exist())
 258                 queue_work(slow_path_wq, &slow_path_work);
 259 }
 260
 261 struct res_acc_data {
 262         struct chp_id chpid;
 263         u32 fla_mask;
 264         u16 fla;
 265 };
 266
 267 static int s390_process_res_acc_sch(struct res_acc_data *res_data,
 268                                     struct subchannel *sch)
 269 {
 270         int found;
 271         int chp;
 272         int ccode;
 273
 274         found = 0;
 275         for (chp = 0; chp <= 7; chp++)
 276                 /*
 277                  * check if chpid is in information updated by ssd
 278                  */
 279                 if (sch->ssd_info.valid &&
 280                     sch->ssd_info.chpid[chp] == res_data->chpid.id &&
 281                     (sch->ssd_info.fla[chp] & res_data->fla_mask)
 282                     == res_data->fla) {
 283                         found = 1;
 284                         break;
 285                 }
 286
 287         if (found == 0)
 288                 return 0;
 289
 290         /*
 291          * Do a stsch to update our subchannel structure with the
 292          * new path information and eventually check for logically
 293          * offline chpids.
 294          */
 295         ccode = stsch(sch->schid, &sch->schib);
 296         if (ccode > 0)
 297                 return 0;
 298
 299         return 0x80 >> chp;
 300 }
 301
 302 static int
 303 s390_process_res_acc_new_sch(struct subchannel_id schid)
 304 {
 305         struct schib schib;
 306         int ret;
 307         /*
 308          * We don't know the device yet, but since a path
 309          * may be available now to the device we'll have
 310          * to do recognition again.
 311          * Since we don't have any idea about which chpid
 312          * that beast may be on we'll have to do a stsch
 313          * on all devices, grr...
 314          */
 315         if (stsch_err(schid, &schib))
 316                 /* We're through */
 317                 return need_rescan ? -EAGAIN : -ENXIO;
 318
 319         /* Put it on the slow path. */
 320         ret = css_enqueue_subchannel_slow(schid);
 321         if (ret) {
 322                 css_clear_subchannel_slow_list();
 323                 need_rescan = 1;
 324                 return -EAGAIN;
 325         }
 326         return 0;
 327 }
 328
 329 static int
 330 __s390_process_res_acc(struct subchannel_id schid, void *data)
 331 {
 332         int chp_mask, old_lpm;
 333         struct res_acc_data *res_data;
 334         struct subchannel *sch;
 335
 336         res_data = data;
 337         sch = get_subchannel_by_schid(schid);
 338         if (!sch)
 339                 /* Check if a subchannel is newly available. */
 340                 return s390_process_res_acc_new_sch(schid);
 341
 342         spin_lock_irq(sch->lock);
 343
 344         chp_mask = s390_process_res_acc_sch(res_data, sch);
 345
 346         if (chp_mask == 0) {
 347                 spin_unlock_irq(sch->lock);
 348                 put_device(&sch->dev);
 349                 return 0;
 350         }
 351         old_lpm = sch->lpm;
 352         sch->lpm = ((sch->schib.pmcw.pim &
 353                      sch->schib.pmcw.pam &
 354                      sch->schib.pmcw.pom)
 355                     | chp_mask) & sch->opm;
 356         if (!old_lpm && sch->lpm)
 357                 device_trigger_reprobe(sch);
 358         else if (sch->driver && sch->driver->verify)
 359                 sch->driver->verify(&sch->dev);
 360
 361         spin_unlock_irq(sch->lock);
 362         put_device(&sch->dev);
 363         return 0;
 364 }
 365
 366
 367 static int
 368 s390_process_res_acc (struct res_acc_data *res_data)
 369 {
 370         int rc;
 371         char dbf_txt[15];
 372
 373         sprintf(dbf_txt, "accpr%x.%02x", res_data->chpid.cssid,
 374                 res_data->chpid.id);
 375         CIO_TRACE_EVENT( 2, dbf_txt);
 376         if (res_data->fla != 0) {
 377                 sprintf(dbf_txt, "fla%x", res_data->fla);
 378                 CIO_TRACE_EVENT( 2, dbf_txt);
 379         }
 380
 381         /*
 382          * I/O resources may have become accessible.
 383          * Scan through all subchannels that may be concerned and
 384          * do a validation on those.
 385          * The more information we have (info), the less scanning
 386          * will we have to do.
 387          */
 388         rc = for_each_subchannel(__s390_process_res_acc, res_data);
 389         if (css_slow_subchannels_exist())
 390                 rc = -EAGAIN;
 391         else if (rc != -EAGAIN)
 392                 rc = 0;
 393         return rc;
 394 }
 395
 396 static int
 397 __get_chpid_from_lir(void *data)
 398 {
 399         struct lir {
 400                 u8  iq;
 401                 u8  ic;
 402                 u16 sci;
 403                 /* incident-node descriptor */
 404                 u32 indesc[28];
 405                 /* attached-node descriptor */
 406                 u32 andesc[28];
 407                 /* incident-specific information */
 408                 u32 isinfo[28];
 409         } __attribute__ ((packed)) *lir;
 410
 411         lir = data;
 412         if (!(lir->iq&0x80))
 413                 /* NULL link incident record */
 414                 return -EINVAL;
 415         if (!(lir->indesc[0]&0xc0000000))
 416                 /* node descriptor not valid */
 417                 return -EINVAL;
 418         if (!(lir->indesc[0]&0x10000000))
 419                 /* don't handle device-type nodes - FIXME */
 420                 return -EINVAL;
 421         /* Byte 3 contains the chpid. Could also be CTCA, but we don't care */
 422
 423         return (u16) (lir->indesc[0]&0x000000ff);
 424 }
 425
 426 struct chsc_sei_area {
 427         struct chsc_header request;
 428         u32 reserved1;
 429         u32 reserved2;
 430         u32 reserved3;
 431         struct chsc_header response;
 432         u32 reserved4;
 433         u8  flags;
 434         u8  vf;         /* validity flags */
 435         u8  rs;         /* reporting source */
 436         u8  cc;         /* content code */
 437         u16 fla;        /* full link address */
 438         u16 rsid;       /* reporting source id */
 439         u32 reserved5;
 440         u32 reserved6;
 441         u8 ccdf[4096 - 16 - 24];        /* content-code dependent field */
 442         /* ccdf has to be big enough for a link-incident record */
 443 } __attribute__ ((packed));
 444
 445 static int chsc_process_sei_link_incident(struct chsc_sei_area *sei_area)
 446 {
 447         struct chp_id chpid;
 448         int id;
 449
 450         CIO_CRW_EVENT(4, "chsc: link incident (rs=%02x, rs_id=%04x)\n",
 451                       sei_area->rs, sei_area->rsid);
 452         if (sei_area->rs != 4)
 453                 return 0;
 454         id = __get_chpid_from_lir(sei_area->ccdf);
 455         if (id < 0)
 456                 CIO_CRW_EVENT(4, "chsc: link incident - invalid LIR\n");
 457         else {
 458                 chp_id_init(&chpid);
 459                 chpid.id = id;
 460                 chsc_chp_offline(chpid);
 461         }
 462
 463         return 0;
 464 }
 465
 466 static int chsc_process_sei_res_acc(struct chsc_sei_area *sei_area)
 467 {
 468         struct res_acc_data res_data;
 469         struct chp_id chpid;
 470         int status;
 471         int rc;
 472
 473         CIO_CRW_EVENT(4, "chsc: resource accessibility event (rs=%02x, "
 474                       "rs_id=%04x)\n", sei_area->rs, sei_area->rsid);
 475         if (sei_area->rs != 4)
 476                 return 0;
 477         chp_id_init(&chpid);
 478         chpid.id = sei_area->rsid;
 479         /* allocate a new channel path structure, if needed */
 480         status = chp_get_status(chpid);
 481         if (status < 0)
 482                 chp_new(chpid);
 483         else if (!status)
 484                 return 0;
 485         memset(&res_data, 0, sizeof(struct res_acc_data));
 486         res_data.chpid = chpid;
 487         if ((sei_area->vf & 0xc0) != 0) {
 488                 res_data.fla = sei_area->fla;
 489                 if ((sei_area->vf & 0xc0) == 0xc0)
 490                         /* full link address */
 491                         res_data.fla_mask = 0xffff;
 492                 else
 493                         /* link address */
 494                         res_data.fla_mask = 0xff00;
 495         }
 496         rc = s390_process_res_acc(&res_data);
 497
 498         return rc;
 499 }
 500
 501 static int chsc_process_sei(struct chsc_sei_area *sei_area)
 502 {
 503         int rc;
 504
 505         /* Check if we might have lost some information. */
 506         if (sei_area->flags & 0x40)
 507                 CIO_CRW_EVENT(2, "chsc: event overflow\n");
 508         /* which kind of information was stored? */
 509         rc = 0;
 510         switch (sei_area->cc) {
 511         case 1: /* link incident*/
 512                 rc = chsc_process_sei_link_incident(sei_area);
 513                 break;
 514         case 2: /* i/o resource accessibiliy */
 515                 rc = chsc_process_sei_res_acc(sei_area);
 516                 break;
 517         default: /* other stuff */
 518                 CIO_CRW_EVENT(4, "chsc: unhandled sei content code %d\n",
 519                               sei_area->cc);
 520                 break;
 521         }
 522
 523         return rc;
 524 }
 525
 526 int chsc_process_crw(void)
 527 {
 528         struct chsc_sei_area *sei_area;
 529         int ret;
 530         int rc;
 531
 532         if (!sei_page)
 533                 return 0;
 534         /* Access to sei_page is serialized through machine check handler
 535          * thread, so no need for locking. */
 536         sei_area = sei_page;
 537
 538         CIO_TRACE_EVENT( 2, "prcss");
 539         ret = 0;
 540         do {
 541                 memset(sei_area, 0, sizeof(*sei_area));
 542                 sei_area->request.length = 0x0010;
 543                 sei_area->request.code = 0x000e;
 544                 if (chsc(sei_area))
 545                         break;
 546
 547                 if (sei_area->response.code == 0x0001) {
 548                         CIO_CRW_EVENT(4, "chsc: sei successful\n");
 549                         rc = chsc_process_sei(sei_area);
 550                         if (rc)
 551                                 ret = rc;
 552                 } else {
 553                         CIO_CRW_EVENT(2, "chsc: sei failed (rc=%04x)\n",
 554                                       sei_area->response.code);
 555                         ret = 0;
 556                         break;
 557                 }
 558         } while (sei_area->flags & 0x80);
 559
 560         return ret;
 561 }
 562
 563 static int
 564 __chp_add_new_sch(struct subchannel_id schid)
 565 {
 566         struct schib schib;
 567         int ret;
 568
 569         if (stsch_err(schid, &schib))
 570                 /* We're through */
 571                 return need_rescan ? -EAGAIN : -ENXIO;
 572
 573         /* Put it on the slow path. */
 574         ret = css_enqueue_subchannel_slow(schid);
 575         if (ret) {
 576                 css_clear_subchannel_slow_list();
 577                 need_rescan = 1;
 578                 return -EAGAIN;
 579         }
 580         return 0;
 581 }
 582
 583
 584 static int
 585 __chp_add(struct subchannel_id schid, void *data)
 586 {
 587         int i, mask;
 588         struct chp_id *chpid;
 589         struct subchannel *sch;
 590
 591         chpid = data;
 592         sch = get_subchannel_by_schid(schid);
 593         if (!sch)
 594                 /* Check if the subchannel is now available. */
 595                 return __chp_add_new_sch(schid);
 596         spin_lock_irq(sch->lock);
 597         for (i=0; i<8; i++) {
 598                 mask = 0x80 >> i;
 599                 if ((sch->schib.pmcw.pim & mask) &&
 600                     (sch->schib.pmcw.chpid[i] == chpid->id)) {
 601                         if (stsch(sch->schid, &sch->schib) != 0) {
 602                                 /* Endgame. */
 603                                 spin_unlock_irq(sch->lock);
 604                                 return -ENXIO;
 605                         }
 606                         break;
 607                 }
 608         }
 609         if (i==8) {
 610                 spin_unlock_irq(sch->lock);
 611                 return 0;
 612         }
 613         sch->lpm = ((sch->schib.pmcw.pim &
 614                      sch->schib.pmcw.pam &
 615                      sch->schib.pmcw.pom)
 616                     | mask) & sch->opm;
 617
 618         if (sch->driver && sch->driver->verify)
 619                 sch->driver->verify(&sch->dev);
 620
 621         spin_unlock_irq(sch->lock);
 622         put_device(&sch->dev);
 623         return 0;
 624 }
 625
 626 int chsc_chp_online(struct chp_id chpid)
 627 {
 628         int rc;
 629         char dbf_txt[15];
 630
 631         sprintf(dbf_txt, "cadd%x.%02x", chpid.cssid, chpid.id);
 632         CIO_TRACE_EVENT(2, dbf_txt);
 633
 634         if (chp_get_status(chpid) == 0)
 635                 return 0;
 636         rc = for_each_subchannel(__chp_add, &chpid);
 637         if (css_slow_subchannels_exist())
 638                 rc = -EAGAIN;
 639         if (rc != -EAGAIN)
 640                 rc = 0;
 641         return rc;
 642 }
 643
 644 static int check_for_io_on_path(struct subchannel *sch, int index)
 645 {
 646         int cc;
 647
 648         cc = stsch(sch->schid, &sch->schib);
 649         if (cc)
 650                 return 0;
 651         if (sch->schib.scsw.actl && sch->schib.pmcw.lpum == (0x80 >> index))
 652                 return 1;
 653         return 0;
 654 }
 655
 656 static void terminate_internal_io(struct subchannel *sch)
 657 {
 658         if (cio_clear(sch)) {
 659                 /* Recheck device in case clear failed. */
 660                 sch->lpm = 0;
 661                 if (device_trigger_verify(sch) != 0) {
 662                         if(css_enqueue_subchannel_slow(sch->schid)) {
 663                                 css_clear_subchannel_slow_list();
 664                                 need_rescan = 1;
 665                         }
 666                 }
 667                 return;
 668         }
 669         /* Request retry of internal operation. */
 670         device_set_intretry(sch);
 671         /* Call handler. */
 672         if (sch->driver && sch->driver->termination)
 673                 sch->driver->termination(&sch->dev);
 674 }
 675
 676 static void __s390_subchannel_vary_chpid(struct subchannel *sch,
 677                                          struct chp_id chpid, int on)
 678 {
 679         int chp, old_lpm;
 680         unsigned long flags;
 681
 682         if (!sch->ssd_info.valid)
 683                 return;
 684
 685         spin_lock_irqsave(sch->lock, flags);
 686         old_lpm = sch->lpm;
 687         for (chp = 0; chp < 8; chp++) {
 688                 if (sch->ssd_info.chpid[chp] != chpid.id)
 689                         continue;
 690
 691                 if (on) {
 692                         sch->opm |= (0x80 >> chp);
 693                         sch->lpm |= (0x80 >> chp);
 694                         if (!old_lpm)
 695                                 device_trigger_reprobe(sch);
 696                         else if (sch->driver && sch->driver->verify)
 697                                 sch->driver->verify(&sch->dev);
 698                         break;
 699                 }
 700                 sch->opm &= ~(0x80 >> chp);
 701                 sch->lpm &= ~(0x80 >> chp);
 702                 if (check_for_io_on_path(sch, chp)) {
 703                         if (device_is_online(sch))
 704                                 /* Path verification is done after killing. */
 705                                 device_kill_io(sch);
 706                         else
 707                                 /* Kill and retry internal I/O. */
 708                                 terminate_internal_io(sch);
 709                 } else if (!sch->lpm) {
 710                         if (device_trigger_verify(sch) != 0) {
 711                                 if (css_enqueue_subchannel_slow(sch->schid)) {
 712                                         css_clear_subchannel_slow_list();
 713                                         need_rescan = 1;
 714                                 }
 715                         }
 716                 } else if (sch->driver && sch->driver->verify)
 717                         sch->driver->verify(&sch->dev);
 718                 break;
 719         }
 720         spin_unlock_irqrestore(sch->lock, flags);
 721 }
 722
 723 static int s390_subchannel_vary_chpid_off(struct device *dev, void *data)
 724 {
 725         struct subchannel *sch;
 726         struct chp_id *chpid;
 727
 728         sch = to_subchannel(dev);
 729         chpid = data;
 730
 731         __s390_subchannel_vary_chpid(sch, *chpid, 0);
 732         return 0;
 733 }
 734
 735 static int s390_subchannel_vary_chpid_on(struct device *dev, void *data)
 736 {
 737         struct subchannel *sch;
 738         struct chp_id *chpid;
 739
 740         sch = to_subchannel(dev);
 741         chpid = data;
 742
 743         __s390_subchannel_vary_chpid(sch, *chpid, 1);
 744         return 0;
 745 }
 746
 747 static int
 748 __s390_vary_chpid_on(struct subchannel_id schid, void *data)
 749 {
 750         struct schib schib;
 751         struct subchannel *sch;
 752
 753         sch = get_subchannel_by_schid(schid);
 754         if (sch) {
 755                 put_device(&sch->dev);
 756                 return 0;
 757         }
 758         if (stsch_err(schid, &schib))
 759                 /* We're through */
 760                 return -ENXIO;
 761         /* Put it on the slow path. */
 762         if (css_enqueue_subchannel_slow(schid)) {
 763                 css_clear_subchannel_slow_list();
 764                 need_rescan = 1;
 765                 return -EAGAIN;
 766         }
 767         return 0;
 768 }
 769
 770 /**
 771  * chsc_chp_vary - propagate channel-path vary operation to subchannels
 772  * @chpid: channl-path ID
 773  * @on: non-zero for vary online, zero for vary offline
 774  */
 775 int chsc_chp_vary(struct chp_id chpid, int on)
 776 {
 777         /*
 778          * Redo PathVerification on the devices the chpid connects to
 779          */
 780
 781         bus_for_each_dev(&css_bus_type, NULL, &chpid, on ?
 782                          s390_subchannel_vary_chpid_on :
 783                          s390_subchannel_vary_chpid_off);
 784         if (on)
 785                 /* Scan for new devices on varied on path. */
 786                 for_each_subchannel(__s390_vary_chpid_on, NULL);
 787         if (need_rescan || css_slow_subchannels_exist())
 788                 queue_work(slow_path_wq, &slow_path_work);
 789         return 0;
 790 }
 791
 792 static void
 793 chsc_remove_cmg_attr(struct channel_subsystem *css)
 794 {
 795         int i;
 796
 797         for (i = 0; i <= __MAX_CHPID; i++) {
 798                 if (!css->chps[i])
 799                         continue;
 800                 chp_remove_cmg_attr(css->chps[i]);
 801         }
 802 }
 803
 804 static int
 805 chsc_add_cmg_attr(struct channel_subsystem *css)
 806 {
 807         int i, ret;
 808
 809         ret = 0;
 810         for (i = 0; i <= __MAX_CHPID; i++) {
 811                 if (!css->chps[i])
 812                         continue;
 813                 ret = chp_add_cmg_attr(css->chps[i]);
 814                 if (ret)
 815                         goto cleanup;
 816         }
 817         return ret;
 818 cleanup:
 819         for (--i; i >= 0; i--) {
 820                 if (!css->chps[i])
 821                         continue;
 822                 chp_remove_cmg_attr(css->chps[i]);
 823         }
 824         return ret;
 825 }
 826
 827 static int
 828 __chsc_do_secm(struct channel_subsystem *css, int enable, void *page)
 829 {
 830         struct {
 831                 struct chsc_header request;
 832                 u32 operation_code : 2;
 833                 u32 : 30;
 834                 u32 key : 4;
 835                 u32 : 28;
 836                 u32 zeroes1;
 837                 u32 cub_addr1;
 838                 u32 zeroes2;
 839                 u32 cub_addr2;
 840                 u32 reserved[13];
 841                 struct chsc_header response;
 842                 u32 status : 8;
 843                 u32 : 4;
 844                 u32 fmt : 4;
 845                 u32 : 16;
 846         } __attribute__ ((packed)) *secm_area;
 847         int ret, ccode;
 848
 849         secm_area = page;
 850         secm_area->request.length = 0x0050;
 851         secm_area->request.code = 0x0016;
 852
 853         secm_area->key = PAGE_DEFAULT_KEY;
 854         secm_area->cub_addr1 = (u64)(unsigned long)css->cub_addr1;
 855         secm_area->cub_addr2 = (u64)(unsigned long)css->cub_addr2;
 856
 857         secm_area->operation_code = enable ? 0 : 1;
 858
 859         ccode = chsc(secm_area);
 860         if (ccode > 0)
 861                 return (ccode == 3) ? -ENODEV : -EBUSY;
 862
 863         switch (secm_area->response.code) {
 864         case 0x0001: /* Success. */
 865                 ret = 0;
 866                 break;
 867         case 0x0003: /* Invalid block. */
 868         case 0x0007: /* Invalid format. */
 869         case 0x0008: /* Other invalid block. */
 870                 CIO_CRW_EVENT(2, "Error in chsc request block!\n");
 871                 ret = -EINVAL;
 872                 break;
 873         case 0x0004: /* Command not provided in model. */
 874                 CIO_CRW_EVENT(2, "Model does not provide secm\n");
 875                 ret = -EOPNOTSUPP;
 876                 break;
 877         case 0x0102: /* cub adresses incorrect */
 878                 CIO_CRW_EVENT(2, "Invalid addresses in chsc request block\n");
 879                 ret = -EINVAL;
 880                 break;
 881         case 0x0103: /* key error */
 882                 CIO_CRW_EVENT(2, "Access key error in secm\n");
 883                 ret = -EINVAL;
 884                 break;
 885         case 0x0105: /* error while starting */
 886                 CIO_CRW_EVENT(2, "Error while starting channel measurement\n");
 887                 ret = -EIO;
 888                 break;
 889         default:
 890                 CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
 891                               secm_area->response.code);
 892                 ret = -EIO;
 893         }
 894         return ret;
 895 }
 896
 897 int
 898 chsc_secm(struct channel_subsystem *css, int enable)
 899 {
 900         void  *secm_area;
 901         int ret;
 902
 903         secm_area = (void *)get_zeroed_page(GFP_KERNEL |  GFP_DMA);
 904         if (!secm_area)
 905                 return -ENOMEM;
 906
 907         mutex_lock(&css->mutex);
 908         if (enable && !css->cm_enabled) {
 909                 css->cub_addr1 = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
 910                 css->cub_addr2 = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
 911                 if (!css->cub_addr1 || !css->cub_addr2) {
 912                         free_page((unsigned long)css->cub_addr1);
 913                         free_page((unsigned long)css->cub_addr2);
 914                         free_page((unsigned long)secm_area);
 915                         mutex_unlock(&css->mutex);
 916                         return -ENOMEM;
 917                 }
 918         }
 919         ret = __chsc_do_secm(css, enable, secm_area);
 920         if (!ret) {
 921                 css->cm_enabled = enable;
 922                 if (css->cm_enabled) {
 923                         ret = chsc_add_cmg_attr(css);
 924                         if (ret) {
 925                                 memset(secm_area, 0, PAGE_SIZE);
 926                                 __chsc_do_secm(css, 0, secm_area);
 927                                 css->cm_enabled = 0;
 928                         }
 929                 } else
 930                         chsc_remove_cmg_attr(css);
 931         }
 932         if (enable && !css->cm_enabled) {
 933                 free_page((unsigned long)css->cub_addr1);
 934                 free_page((unsigned long)css->cub_addr2);
 935         }
 936         mutex_unlock(&css->mutex);
 937         free_page((unsigned long)secm_area);
 938         return ret;
 939 }
 940
 941 int chsc_determine_channel_path_description(struct chp_id chpid,
 942                                             struct channel_path_desc *desc)
 943 {
 944         int ccode, ret;
 945
 946         struct {
 947                 struct chsc_header request;
 948                 u32 : 24;
 949                 u32 first_chpid : 8;
 950                 u32 : 24;
 951                 u32 last_chpid : 8;
 952                 u32 zeroes1;
 953                 struct chsc_header response;
 954                 u32 zeroes2;
 955                 struct channel_path_desc desc;
 956         } __attribute__ ((packed)) *scpd_area;
 957
 958         scpd_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
 959         if (!scpd_area)
 960                 return -ENOMEM;
 961
 962         scpd_area->request.length = 0x0010;
 963         scpd_area->request.code = 0x0002;
 964
 965         scpd_area->first_chpid = chpid.id;
 966         scpd_area->last_chpid = chpid.id;
 967
 968         ccode = chsc(scpd_area);
 969         if (ccode > 0) {
 970                 ret = (ccode == 3) ? -ENODEV : -EBUSY;
 971                 goto out;
 972         }
 973
 974         switch (scpd_area->response.code) {
 975         case 0x0001: /* Success. */
 976                 memcpy(desc, &scpd_area->desc,
 977                        sizeof(struct channel_path_desc));
 978                 ret = 0;
 979                 break;
 980         case 0x0003: /* Invalid block. */
 981         case 0x0007: /* Invalid format. */
 982         case 0x0008: /* Other invalid block. */
 983                 CIO_CRW_EVENT(2, "Error in chsc request block!\n");
 984                 ret = -EINVAL;
 985                 break;
 986         case 0x0004: /* Command not provided in model. */
 987                 CIO_CRW_EVENT(2, "Model does not provide scpd\n");
 988                 ret = -EOPNOTSUPP;
 989                 break;
 990         default:
 991                 CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
 992                               scpd_area->response.code);
 993                 ret = -EIO;
 994         }
 995 out:
 996         free_page((unsigned long)scpd_area);
 997         return ret;
 998 }
 999
1000 static void
1001 chsc_initialize_cmg_chars(struct channel_path *chp, u8 cmcv,
1002                           struct cmg_chars *chars)
1003 {
1004         switch (chp->cmg) {
1005         case 2:
1006         case 3:
1007                 chp->cmg_chars = kmalloc(sizeof(struct cmg_chars),
1008                                          GFP_KERNEL);
1009                 if (chp->cmg_chars) {
1010                         int i, mask;
1011                         struct cmg_chars *cmg_chars;
1012
1013                         cmg_chars = chp->cmg_chars;
1014                         for (i = 0; i < NR_MEASUREMENT_CHARS; i++) {
1015                                 mask = 0x80 >> (i + 3);
1016                                 if (cmcv & mask)
1017                                         cmg_chars->values[i] = chars->values[i];
1018                                 else
1019                                         cmg_chars->values[i] = 0;
1020                         }
1021                 }
1022                 break;
1023         default:
1024                 /* No cmg-dependent data. */
1025                 break;
1026         }
1027 }
1028
1029 int chsc_get_channel_measurement_chars(struct channel_path *chp)
1030 {
1031         int ccode, ret;
1032
1033         struct {
1034                 struct chsc_header request;
1035                 u32 : 24;
1036                 u32 first_chpid : 8;
1037                 u32 : 24;
1038                 u32 last_chpid : 8;
1039                 u32 zeroes1;
1040                 struct chsc_header response;
1041                 u32 zeroes2;
1042                 u32 not_valid : 1;
1043                 u32 shared : 1;
1044                 u32 : 22;
1045                 u32 chpid : 8;
1046                 u32 cmcv : 5;
1047                 u32 : 11;
1048                 u32 cmgq : 8;
1049                 u32 cmg : 8;
1050                 u32 zeroes3;
1051                 u32 data[NR_MEASUREMENT_CHARS];
1052         } __attribute__ ((packed)) *scmc_area;
1053
1054         scmc_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1055         if (!scmc_area)
1056                 return -ENOMEM;
1057
1058         scmc_area->request.length = 0x0010;
1059         scmc_area->request.code = 0x0022;
1060
1061         scmc_area->first_chpid = chp->chpid.id;
1062         scmc_area->last_chpid = chp->chpid.id;
1063
1064         ccode = chsc(scmc_area);
1065         if (ccode > 0) {
1066                 ret = (ccode == 3) ? -ENODEV : -EBUSY;
1067                 goto out;
1068         }
1069
1070         switch (scmc_area->response.code) {
1071         case 0x0001: /* Success. */
1072                 if (!scmc_area->not_valid) {
1073                         chp->cmg = scmc_area->cmg;
1074                         chp->shared = scmc_area->shared;
1075                         chsc_initialize_cmg_chars(chp, scmc_area->cmcv,
1076                                                   (struct cmg_chars *)
1077                                                   &scmc_area->data);
1078                 } else {
1079                         chp->cmg = -1;
1080                         chp->shared = -1;
1081                 }
1082                 ret = 0;
1083                 break;
1084         case 0x0003: /* Invalid block. */
1085         case 0x0007: /* Invalid format. */
1086         case 0x0008: /* Invalid bit combination. */
1087                 CIO_CRW_EVENT(2, "Error in chsc request block!\n");
1088                 ret = -EINVAL;
1089                 break;
1090         case 0x0004: /* Command not provided. */
1091                 CIO_CRW_EVENT(2, "Model does not provide scmc\n");
1092                 ret = -EOPNOTSUPP;
1093                 break;
1094         default:
1095                 CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
1096                               scmc_area->response.code);
1097                 ret = -EIO;
1098         }
1099 out:
1100         free_page((unsigned long)scmc_area);
1101         return ret;
1102 }
1103
1104 static int __init
1105 chsc_alloc_sei_area(void)
1106 {
1107         sei_page = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1108         if (!sei_page)
1109                 printk(KERN_WARNING"Can't allocate page for processing of " \
1110                        "chsc machine checks!\n");
1111         return (sei_page ? 0 : -ENOMEM);
1112 }
1113
1114 int __init
1115 chsc_enable_facility(int operation_code)
1116 {
1117         int ret;
1118         struct {
1119                 struct chsc_header request;
1120                 u8 reserved1:4;
1121                 u8 format:4;
1122                 u8 reserved2;
1123                 u16 operation_code;
1124                 u32 reserved3;
1125                 u32 reserved4;
1126                 u32 operation_data_area[252];
1127                 struct chsc_header response;
1128                 u32 reserved5:4;
1129                 u32 format2:4;
1130                 u32 reserved6:24;
1131         } __attribute__ ((packed)) *sda_area;
1132
1133         sda_area = (void *)get_zeroed_page(GFP_KERNEL|GFP_DMA);
1134         if (!sda_area)
1135                 return -ENOMEM;
1136         sda_area->request.length = 0x0400;
1137         sda_area->request.code = 0x0031;
1138         sda_area->operation_code = operation_code;
1139
1140         ret = chsc(sda_area);
1141         if (ret > 0) {
1142                 ret = (ret == 3) ? -ENODEV : -EBUSY;
1143                 goto out;
1144         }
1145         switch (sda_area->response.code) {
1146         case 0x0001: /* everything ok */
1147                 ret = 0;
1148                 break;
1149         case 0x0003: /* invalid request block */
1150         case 0x0007:
1151                 ret = -EINVAL;
1152                 break;
1153         case 0x0004: /* command not provided */
1154         case 0x0101: /* facility not provided */
1155                 ret = -EOPNOTSUPP;
1156                 break;
1157         default: /* something went wrong */
1158                 ret = -EIO;
1159         }
1160  out:
1161         free_page((unsigned long)sda_area);
1162         return ret;
1163 }
1164
1165 subsys_initcall(chsc_alloc_sei_area);
1166
1167 struct css_general_char css_general_characteristics;
1168 struct css_chsc_char css_chsc_characteristics;
1169
1170 int __init
1171 chsc_determine_css_characteristics(void)
1172 {
1173         int result;
1174         struct {
1175                 struct chsc_header request;
1176                 u32 reserved1;
1177                 u32 reserved2;
1178                 u32 reserved3;
1179                 struct chsc_header response;
1180                 u32 reserved4;
1181                 u32 general_char[510];
1182                 u32 chsc_char[518];
1183         } __attribute__ ((packed)) *scsc_area;
1184
1185         scsc_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1186         if (!scsc_area) {
1187                 printk(KERN_WARNING"cio: Was not able to determine available" \
1188                        "CHSCs due to no memory.\n");
1189                 return -ENOMEM;
1190         }
1191
1192         scsc_area->request.length = 0x0010;
1193         scsc_area->request.code = 0x0010;
1194
1195         result = chsc(scsc_area);
1196         if (result) {
1197                 printk(KERN_WARNING"cio: Was not able to determine " \
1198                        "available CHSCs, cc=%i.\n", result);
1199                 result = -EIO;
1200                 goto exit;
1201         }
1202
1203         if (scsc_area->response.code != 1) {
1204                 printk(KERN_WARNING"cio: Was not able to determine " \
1205                        "available CHSCs.\n");
1206                 result = -EIO;
1207                 goto exit;
1208         }
1209         memcpy(&css_general_characteristics, scsc_area->general_char,
1210                sizeof(css_general_characteristics));
1211         memcpy(&css_chsc_characteristics, scsc_area->chsc_char,
1212                sizeof(css_chsc_characteristics));
1213 exit:
1214         free_page ((unsigned long) scsc_area);
1215         return result;
1216 }
1217
1218 EXPORT_SYMBOL_GPL(css_general_characteristics);
1219 EXPORT_SYMBOL_GPL(css_chsc_characteristics);