Pileus Git - ~andy/linux/blob - drivers/s390/cio/device_pgid.c

   1 /*
   2  * drivers/s390/cio/device_pgid.c
   3  *
   4  *    Copyright (C) 2002 IBM Deutschland Entwicklung GmbH,
   5  *                       IBM Corporation
   6  *    Author(s): Cornelia Huck(cohuck@de.ibm.com)
   7  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
   8  *
   9  * Path Group ID functions.
  10  */
  11
  12 #include <linux/config.h>
  13 #include <linux/module.h>
  14 #include <linux/init.h>
  15
  16 #include <asm/ccwdev.h>
  17 #include <asm/cio.h>
  18 #include <asm/delay.h>
  19 #include <asm/lowcore.h>
  20
  21 #include "cio.h"
  22 #include "cio_debug.h"
  23 #include "css.h"
  24 #include "device.h"
  25 #include "ioasm.h"
  26
  27 /*
  28  * Start Sense Path Group ID helper function. Used in ccw_device_recog
  29  * and ccw_device_sense_pgid.
  30  */
  31 static int
  32 __ccw_device_sense_pgid_start(struct ccw_device *cdev)
  33 {
  34         struct subchannel *sch;
  35         struct ccw1 *ccw;
  36         int ret;
  37
  38         sch = to_subchannel(cdev->dev.parent);
  39         /* Setup sense path group id channel program. */
  40         ccw = cdev->private->iccws;
  41         ccw->cmd_code = CCW_CMD_SENSE_PGID;
  42         ccw->cda = (__u32) __pa (&cdev->private->pgid);
  43         ccw->count = sizeof (struct pgid);
  44         ccw->flags = CCW_FLAG_SLI;
  45
  46         /* Reset device status. */
  47         memset(&cdev->private->irb, 0, sizeof(struct irb));
  48         /* Try on every path. */
  49         ret = -ENODEV;
  50         while (cdev->private->imask != 0) {
  51                 /* Try every path multiple times. */
  52                 if (cdev->private->iretry > 0) {
  53                         cdev->private->iretry--;
  54                         ret = cio_start (sch, cdev->private->iccws,
  55                                          cdev->private->imask);
  56                         /* ret is 0, -EBUSY, -EACCES or -ENODEV */
  57                         if (ret != -EACCES)
  58                                 return ret;
  59                         CIO_MSG_EVENT(2, "SNID - Device %04x on Subchannel "
  60                                       "%04x, lpm %02X, became 'not "
  61                                       "operational'\n",
  62                                       cdev->private->devno, sch->schid.sch_no,
  63                                       cdev->private->imask);
  64
  65                 }
  66                 cdev->private->imask >>= 1;
  67                 cdev->private->iretry = 5;
  68         }
  69         return ret;
  70 }
  71
  72 void
  73 ccw_device_sense_pgid_start(struct ccw_device *cdev)
  74 {
  75         int ret;
  76
  77         cdev->private->state = DEV_STATE_SENSE_PGID;
  78         cdev->private->imask = 0x80;
  79         cdev->private->iretry = 5;
  80         memset (&cdev->private->pgid, 0, sizeof (struct pgid));
  81         ret = __ccw_device_sense_pgid_start(cdev);
  82         if (ret && ret != -EBUSY)
  83                 ccw_device_sense_pgid_done(cdev, ret);
  84 }
  85
  86 /*
  87  * Called from interrupt context to check if a valid answer
  88  * to Sense Path Group ID was received.
  89  */
  90 static int
  91 __ccw_device_check_sense_pgid(struct ccw_device *cdev)
  92 {
  93         struct subchannel *sch;
  94         struct irb *irb;
  95
  96         sch = to_subchannel(cdev->dev.parent);
  97         irb = &cdev->private->irb;
  98         if (irb->scsw.fctl & (SCSW_FCTL_HALT_FUNC | SCSW_FCTL_CLEAR_FUNC))
  99                 return -ETIME;
 100         if (irb->esw.esw0.erw.cons &&
 101             (irb->ecw[0]&(SNS0_CMD_REJECT|SNS0_INTERVENTION_REQ))) {
 102                 /*
 103                  * If the device doesn't support the Sense Path Group ID
 104                  *  command further retries wouldn't help ...
 105                  */
 106                 return -EOPNOTSUPP;
 107         }
 108         if (irb->esw.esw0.erw.cons) {
 109                 CIO_MSG_EVENT(2, "SNID - device %04x, unit check, "
 110                               "lpum %02X, cnt %02d, sns : "
 111                               "%02X%02X%02X%02X %02X%02X%02X%02X ...\n",
 112                               cdev->private->devno,
 113                               irb->esw.esw0.sublog.lpum,
 114                               irb->esw.esw0.erw.scnt,
 115                               irb->ecw[0], irb->ecw[1],
 116                               irb->ecw[2], irb->ecw[3],
 117                               irb->ecw[4], irb->ecw[5],
 118                               irb->ecw[6], irb->ecw[7]);
 119                 return -EAGAIN;
 120         }
 121         if (irb->scsw.cc == 3) {
 122                 CIO_MSG_EVENT(2, "SNID - Device %04x on Subchannel "
 123                               "%04x, lpm %02X, became 'not operational'\n",
 124                               cdev->private->devno, sch->schid.sch_no,
 125                               sch->orb.lpm);
 126                 return -EACCES;
 127         }
 128         if (cdev->private->pgid.inf.ps.state2 == SNID_STATE2_RESVD_ELSE) {
 129                 CIO_MSG_EVENT(2, "SNID - Device %04x on Subchannel %04x "
 130                               "is reserved by someone else\n",
 131                               cdev->private->devno, sch->schid.sch_no);
 132                 return -EUSERS;
 133         }
 134         return 0;
 135 }
 136
 137 /*
 138  * Got interrupt for Sense Path Group ID.
 139  */
 140 void
 141 ccw_device_sense_pgid_irq(struct ccw_device *cdev, enum dev_event dev_event)
 142 {
 143         struct subchannel *sch;
 144         struct irb *irb;
 145         int ret;
 146
 147         irb = (struct irb *) __LC_IRB;
 148         /* Retry sense pgid for cc=1. */
 149         if (irb->scsw.stctl ==
 150             (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) {
 151                 if (irb->scsw.cc == 1) {
 152                         ret = __ccw_device_sense_pgid_start(cdev);
 153                         if (ret && ret != -EBUSY)
 154                                 ccw_device_sense_pgid_done(cdev, ret);
 155                 }
 156                 return;
 157         }
 158         if (ccw_device_accumulate_and_sense(cdev, irb) != 0)
 159                 return;
 160         sch = to_subchannel(cdev->dev.parent);
 161         ret = __ccw_device_check_sense_pgid(cdev);
 162         memset(&cdev->private->irb, 0, sizeof(struct irb));
 163         switch (ret) {
 164         /* 0, -ETIME, -EOPNOTSUPP, -EAGAIN, -EACCES or -EUSERS */
 165         case 0:                 /* Sense Path Group ID successful. */
 166                 if (cdev->private->pgid.inf.ps.state1 == SNID_STATE1_RESET)
 167                         memcpy(&cdev->private->pgid, &global_pgid,
 168                                sizeof(struct pgid));
 169                 ccw_device_sense_pgid_done(cdev, 0);
 170                 break;
 171         case -EOPNOTSUPP:       /* Sense Path Group ID not supported */
 172                 ccw_device_sense_pgid_done(cdev, -EOPNOTSUPP);
 173                 break;
 174         case -ETIME:            /* Sense path group id stopped by timeout. */
 175                 ccw_device_sense_pgid_done(cdev, -ETIME);
 176                 break;
 177         case -EACCES:           /* channel is not operational. */
 178                 sch->lpm &= ~cdev->private->imask;
 179                 cdev->private->imask >>= 1;
 180                 cdev->private->iretry = 5;
 181                 /* Fall through. */
 182         case -EAGAIN:           /* Try again. */
 183                 ret = __ccw_device_sense_pgid_start(cdev);
 184                 if (ret != 0 && ret != -EBUSY)
 185                         ccw_device_sense_pgid_done(cdev, -ENODEV);
 186                 break;
 187         case -EUSERS:           /* device is reserved for someone else. */
 188                 ccw_device_sense_pgid_done(cdev, -EUSERS);
 189                 break;
 190         }
 191 }
 192
 193 /*
 194  * Path Group ID helper function.
 195  */
 196 static int
 197 __ccw_device_do_pgid(struct ccw_device *cdev, __u8 func)
 198 {
 199         struct subchannel *sch;
 200         struct ccw1 *ccw;
 201         int ret;
 202
 203         sch = to_subchannel(cdev->dev.parent);
 204
 205         /* Setup sense path group id channel program. */
 206         cdev->private->pgid.inf.fc = func;
 207         ccw = cdev->private->iccws;
 208         if (!cdev->private->flags.pgid_single) {
 209                 cdev->private->pgid.inf.fc |= SPID_FUNC_MULTI_PATH;
 210                 ccw->cmd_code = CCW_CMD_SUSPEND_RECONN;
 211                 ccw->cda = 0;
 212                 ccw->count = 0;
 213                 ccw->flags = CCW_FLAG_SLI | CCW_FLAG_CC;
 214                 ccw++;
 215         } else
 216                 cdev->private->pgid.inf.fc |= SPID_FUNC_SINGLE_PATH;
 217
 218         ccw->cmd_code = CCW_CMD_SET_PGID;
 219         ccw->cda = (__u32) __pa (&cdev->private->pgid);
 220         ccw->count = sizeof (struct pgid);
 221         ccw->flags = CCW_FLAG_SLI;
 222
 223         /* Reset device status. */
 224         memset(&cdev->private->irb, 0, sizeof(struct irb));
 225
 226         /* Try multiple times. */
 227         ret = -ENODEV;
 228         if (cdev->private->iretry > 0) {
 229                 cdev->private->iretry--;
 230                 ret = cio_start (sch, cdev->private->iccws,
 231                                  cdev->private->imask);
 232                 /* ret is 0, -EBUSY, -EACCES or -ENODEV */
 233                 if ((ret != -EACCES) && (ret != -ENODEV))
 234                         return ret;
 235         }
 236         /* PGID command failed on this path. Switch it off. */
 237         sch->lpm &= ~cdev->private->imask;
 238         sch->vpm &= ~cdev->private->imask;
 239         CIO_MSG_EVENT(2, "SPID - Device %04x on Subchannel "
 240                       "%04x, lpm %02X, became 'not operational'\n",
 241                       cdev->private->devno, sch->schid.sch_no, cdev->private->imask);
 242         return ret;
 243 }
 244
 245 /*
 246  * Called from interrupt context to check if a valid answer
 247  * to Set Path Group ID was received.
 248  */
 249 static int
 250 __ccw_device_check_pgid(struct ccw_device *cdev)
 251 {
 252         struct subchannel *sch;
 253         struct irb *irb;
 254
 255         sch = to_subchannel(cdev->dev.parent);
 256         irb = &cdev->private->irb;
 257         if (irb->scsw.fctl & (SCSW_FCTL_HALT_FUNC | SCSW_FCTL_CLEAR_FUNC))
 258                 return -ETIME;
 259         if (irb->esw.esw0.erw.cons) {
 260                 if (irb->ecw[0] & SNS0_CMD_REJECT)
 261                         return -EOPNOTSUPP;
 262                 /* Hmm, whatever happened, try again. */
 263                 CIO_MSG_EVENT(2, "SPID - device %04x, unit check, cnt %02d, "
 264                               "sns : %02X%02X%02X%02X %02X%02X%02X%02X ...\n",
 265                               cdev->private->devno, irb->esw.esw0.erw.scnt,
 266                               irb->ecw[0], irb->ecw[1],
 267                               irb->ecw[2], irb->ecw[3],
 268                               irb->ecw[4], irb->ecw[5],
 269                               irb->ecw[6], irb->ecw[7]);
 270                 return -EAGAIN;
 271         }
 272         if (irb->scsw.cc == 3) {
 273                 CIO_MSG_EVENT(2, "SPID - Device %04x on Subchannel "
 274                               "%04x, lpm %02X, became 'not operational'\n",
 275                               cdev->private->devno, sch->schid.sch_no,
 276                               cdev->private->imask);
 277                 return -EACCES;
 278         }
 279         return 0;
 280 }
 281
 282 static void
 283 __ccw_device_verify_start(struct ccw_device *cdev)
 284 {
 285         struct subchannel *sch;
 286         __u8 imask, func;
 287         int ret;
 288
 289         sch = to_subchannel(cdev->dev.parent);
 290         while (sch->vpm != sch->lpm) {
 291                 /* Find first unequal bit in vpm vs. lpm */
 292                 for (imask = 0x80; imask != 0; imask >>= 1)
 293                         if ((sch->vpm & imask) != (sch->lpm & imask))
 294                                 break;
 295                 cdev->private->imask = imask;
 296                 func = (sch->vpm & imask) ?
 297                         SPID_FUNC_RESIGN : SPID_FUNC_ESTABLISH;
 298                 ret = __ccw_device_do_pgid(cdev, func);
 299                 if (ret == 0 || ret == -EBUSY)
 300                         return;
 301                 cdev->private->iretry = 5;
 302         }
 303         ccw_device_verify_done(cdev, (sch->lpm != 0) ? 0 : -ENODEV);
 304 }
 305
 306 /*
 307  * Got interrupt for Set Path Group ID.
 308  */
 309 void
 310 ccw_device_verify_irq(struct ccw_device *cdev, enum dev_event dev_event)
 311 {
 312         struct subchannel *sch;
 313         struct irb *irb;
 314         int ret;
 315
 316         irb = (struct irb *) __LC_IRB;
 317         /* Retry set pgid for cc=1. */
 318         if (irb->scsw.stctl ==
 319             (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) {
 320                 if (irb->scsw.cc == 1)
 321                         __ccw_device_verify_start(cdev);
 322                 return;
 323         }
 324         if (ccw_device_accumulate_and_sense(cdev, irb) != 0)
 325                 return;
 326         sch = to_subchannel(cdev->dev.parent);
 327         ret = __ccw_device_check_pgid(cdev);
 328         memset(&cdev->private->irb, 0, sizeof(struct irb));
 329         switch (ret) {
 330         /* 0, -ETIME, -EAGAIN, -EOPNOTSUPP or -EACCES */
 331         case 0:
 332                 /* Establish or Resign Path Group done. Update vpm. */
 333                 if ((sch->lpm & cdev->private->imask) != 0)
 334                         sch->vpm |= cdev->private->imask;
 335                 else
 336                         sch->vpm &= ~cdev->private->imask;
 337                 cdev->private->iretry = 5;
 338                 __ccw_device_verify_start(cdev);
 339                 break;
 340         case -EOPNOTSUPP:
 341                 /*
 342                  * One of those strange devices which claim to be able
 343                  * to do multipathing but not for Set Path Group ID.
 344                  */
 345                 if (cdev->private->flags.pgid_single) {
 346                         ccw_device_verify_done(cdev, -EOPNOTSUPP);
 347                         break;
 348                 }
 349                 cdev->private->flags.pgid_single = 1;
 350                 /* fall through. */
 351         case -EAGAIN:           /* Try again. */
 352                 __ccw_device_verify_start(cdev);
 353                 break;
 354         case -ETIME:            /* Set path group id stopped by timeout. */
 355                 ccw_device_verify_done(cdev, -ETIME);
 356                 break;
 357         case -EACCES:           /* channel is not operational. */
 358                 sch->lpm &= ~cdev->private->imask;
 359                 sch->vpm &= ~cdev->private->imask;
 360                 cdev->private->iretry = 5;
 361                 __ccw_device_verify_start(cdev);
 362                 break;
 363         }
 364 }
 365
 366 void
 367 ccw_device_verify_start(struct ccw_device *cdev)
 368 {
 369         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 370
 371         cdev->private->flags.pgid_single = 0;
 372         cdev->private->iretry = 5;
 373         /*
 374          * Update sch->lpm with current values to catch paths becoming
 375          * available again.
 376          */
 377         if (stsch(sch->schid, &sch->schib)) {
 378                 ccw_device_verify_done(cdev, -ENODEV);
 379                 return;
 380         }
 381         sch->lpm = sch->schib.pmcw.pim &
 382                 sch->schib.pmcw.pam &
 383                 sch->schib.pmcw.pom &
 384                 sch->opm;
 385         __ccw_device_verify_start(cdev);
 386 }
 387
 388 static void
 389 __ccw_device_disband_start(struct ccw_device *cdev)
 390 {
 391         struct subchannel *sch;
 392         int ret;
 393
 394         sch = to_subchannel(cdev->dev.parent);
 395         while (cdev->private->imask != 0) {
 396                 if (sch->lpm & cdev->private->imask) {
 397                         ret = __ccw_device_do_pgid(cdev, SPID_FUNC_DISBAND);
 398                         if (ret == 0)
 399                                 return;
 400                 }
 401                 cdev->private->iretry = 5;
 402                 cdev->private->imask >>= 1;
 403         }
 404         ccw_device_verify_done(cdev, (sch->lpm != 0) ? 0 : -ENODEV);
 405 }
 406
 407 /*
 408  * Got interrupt for Unset Path Group ID.
 409  */
 410 void
 411 ccw_device_disband_irq(struct ccw_device *cdev, enum dev_event dev_event)
 412 {
 413         struct subchannel *sch;
 414         struct irb *irb;
 415         int ret;
 416
 417         irb = (struct irb *) __LC_IRB;
 418         /* Retry set pgid for cc=1. */
 419         if (irb->scsw.stctl ==
 420             (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) {
 421                 if (irb->scsw.cc == 1)
 422                         __ccw_device_disband_start(cdev);
 423                 return;
 424         }
 425         if (ccw_device_accumulate_and_sense(cdev, irb) != 0)
 426                 return;
 427         sch = to_subchannel(cdev->dev.parent);
 428         ret = __ccw_device_check_pgid(cdev);
 429         memset(&cdev->private->irb, 0, sizeof(struct irb));
 430         switch (ret) {
 431         /* 0, -ETIME, -EAGAIN, -EOPNOTSUPP or -EACCES */
 432         case 0:                 /* disband successful. */
 433                 sch->vpm = 0;
 434                 ccw_device_disband_done(cdev, ret);
 435                 break;
 436         case -EOPNOTSUPP:
 437                 /*
 438                  * One of those strange devices which claim to be able
 439                  * to do multipathing but not for Unset Path Group ID.
 440                  */
 441                 cdev->private->flags.pgid_single = 1;
 442                 /* fall through. */
 443         case -EAGAIN:           /* Try again. */
 444                 __ccw_device_disband_start(cdev);
 445                 break;
 446         case -ETIME:            /* Set path group id stopped by timeout. */
 447                 ccw_device_disband_done(cdev, -ETIME);
 448                 break;
 449         case -EACCES:           /* channel is not operational. */
 450                 cdev->private->imask >>= 1;
 451                 cdev->private->iretry = 5;
 452                 __ccw_device_disband_start(cdev);
 453                 break;
 454         }
 455 }
 456
 457 void
 458 ccw_device_disband_start(struct ccw_device *cdev)
 459 {
 460         cdev->private->flags.pgid_single = 0;
 461         cdev->private->iretry = 5;
 462         cdev->private->imask = 0x80;
 463         __ccw_device_disband_start(cdev);
 464 }