sys/bus/cam/cam_periph.c

   1 /*
   2  * Common functions for CAM "type" (peripheral) drivers.
   3  *
   4  * Copyright (c) 1997, 1998 Justin T. Gibbs.
   5  * Copyright (c) 1997, 1998, 1999, 2000 Kenneth D. Merry.
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions, and the following disclaimer,
  13  *    without modification, immediately at the beginning of the file.
  14  * 2. The name of the author may not be used to endorse or promote products
  15  *    derived from this software without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
  21  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * $FreeBSD: src/sys/cam/cam_periph.c,v 1.24.2.3 2003/01/25 19:04:40 dillon Exp $
  30  * $DragonFly: src/sys/bus/cam/cam_periph.c,v 1.12 2006/04/28 00:24:44 dillon Exp $
  31  */
  32
  33 #include <sys/param.h>
  34 #include <sys/systm.h>
  35 #include <sys/types.h>
  36 #include <sys/malloc.h>
  37 #include <sys/linker_set.h>
  38 #include <sys/buf.h>
  39 #include <sys/proc.h>
  40 #include <sys/devicestat.h>
  41 #include <sys/bus.h>
  42 #include <vm/vm.h>
  43 #include <vm/vm_extern.h>
  44
  45 #include <sys/thread2.h>
  46
  47 #include "cam.h"
  48 #include "cam_ccb.h"
  49 #include "cam_xpt_periph.h"
  50 #include "cam_periph.h"
  51 #include "cam_debug.h"
  52
  53 #include <bus/cam/scsi/scsi_all.h>
  54 #include <bus/cam/scsi/scsi_message.h>
  55 #include <bus/cam/scsi/scsi_da.h>
  56 #include <bus/cam/scsi/scsi_pass.h>
  57
  58 static  u_int           camperiphnextunit(struct periph_driver *p_drv,
  59                                           u_int newunit, int wired,
  60                                           path_id_t pathid, target_id_t target,
  61                                           lun_id_t lun);
  62 static  u_int           camperiphunit(struct periph_driver *p_drv,
  63                                       path_id_t pathid, target_id_t target,
  64                                       lun_id_t lun);
  65 static  void            camperiphdone(struct cam_periph *periph,
  66                                         union ccb *done_ccb);
  67 static  void            camperiphfree(struct cam_periph *periph);
  68
  69 cam_status
  70 cam_periph_alloc(periph_ctor_t *periph_ctor,
  71                  periph_oninv_t *periph_oninvalidate,
  72                  periph_dtor_t *periph_dtor, periph_start_t *periph_start,
  73                  char *name, cam_periph_type type, struct cam_path *path,
  74                  ac_callback_t *ac_callback, ac_code code, void *arg)
  75 {
  76         struct          periph_driver **p_drv;
  77         struct          cam_periph *periph;
  78         struct          cam_periph *cur_periph;
  79         path_id_t       path_id;
  80         target_id_t     target_id;
  81         lun_id_t        lun_id;
  82         cam_status      status;
  83         u_int           init_level;
  84
  85         init_level = 0;
  86         /*
  87          * Handle Hot-Plug scenarios.  If there is already a peripheral
  88          * of our type assigned to this path, we are likely waiting for
  89          * final close on an old, invalidated, peripheral.  If this is
  90          * the case, queue up a deferred call to the peripheral's async
  91          * handler.  If it looks like a mistaken re-alloation, complain.
  92          */
  93         if ((periph = cam_periph_find(path, name)) != NULL) {
  94
  95                 if ((periph->flags & CAM_PERIPH_INVALID) != 0
  96                  && (periph->flags & CAM_PERIPH_NEW_DEV_FOUND) == 0) {
  97                         periph->flags |= CAM_PERIPH_NEW_DEV_FOUND;
  98                         periph->deferred_callback = ac_callback;
  99                         periph->deferred_ac = code;
 100                         return (CAM_REQ_INPROG);
 101                 } else {
 102                         printf("cam_periph_alloc: attempt to re-allocate "
 103                                "valid device %s%d rejected\n",
 104                                periph->periph_name, periph->unit_number);
 105                 }
 106                 return (CAM_REQ_INVALID);
 107         }
 108
 109         periph = malloc(sizeof(*periph), M_DEVBUF, M_INTWAIT | M_ZERO);
 110
 111         init_level++;
 112
 113         SET_FOREACH(p_drv, periphdriver_set) {
 114                 if (strcmp((*p_drv)->driver_name, name) == 0)
 115                         break;
 116         }
 117
 118         path_id = xpt_path_path_id(path);
 119         target_id = xpt_path_target_id(path);
 120         lun_id = xpt_path_lun_id(path);
 121         cam_init_pinfo(&periph->pinfo);
 122         periph->periph_start = periph_start;
 123         periph->periph_dtor = periph_dtor;
 124         periph->periph_oninval = periph_oninvalidate;
 125         periph->type = type;
 126         periph->periph_name = name;
 127         periph->unit_number = camperiphunit(*p_drv, path_id, target_id, lun_id);
 128         periph->immediate_priority = CAM_PRIORITY_NONE;
 129         periph->refcount = 0;
 130         SLIST_INIT(&periph->ccb_list);
 131         status = xpt_create_path(&path, periph, path_id, target_id, lun_id);
 132         if (status != CAM_REQ_CMP)
 133                 goto failure;
 134
 135         periph->path = path;
 136         init_level++;
 137
 138         status = xpt_add_periph(periph);
 139
 140         if (status != CAM_REQ_CMP)
 141                 goto failure;
 142
 143         crit_enter();
 144         cur_periph = TAILQ_FIRST(&(*p_drv)->units);
 145         while (cur_periph != NULL
 146             && cur_periph->unit_number < periph->unit_number)
 147                 cur_periph = TAILQ_NEXT(cur_periph, unit_links);
 148
 149         if (cur_periph != NULL)
 150                 TAILQ_INSERT_BEFORE(cur_periph, periph, unit_links);
 151         else {
 152                 TAILQ_INSERT_TAIL(&(*p_drv)->units, periph, unit_links);
 153                 (*p_drv)->generation++;
 154         }
 155
 156         crit_exit();
 157
 158         init_level++;
 159
 160         status = periph_ctor(periph, arg);
 161
 162         if (status == CAM_REQ_CMP)
 163                 init_level++;
 164
 165 failure:
 166         switch (init_level) {
 167         case 4:
 168                 /* Initialized successfully */
 169                 break;
 170         case 3:
 171                 crit_enter();
 172                 TAILQ_REMOVE(&(*p_drv)->units, periph, unit_links);
 173                 crit_exit();
 174                 xpt_remove_periph(periph);
 175         case 2:
 176                 xpt_free_path(periph->path);
 177         case 1:
 178                 free(periph, M_DEVBUF);
 179         case 0:
 180                 /* No cleanup to perform. */
 181                 break;
 182         default:
 183                 panic("cam_periph_alloc: Unkown init level");
 184         }
 185         return(status);
 186 }
 187
 188 /*
 189  * Find a peripheral structure with the specified path, target, lun,
 190  * and (optionally) type.  If the name is NULL, this function will return
 191  * the first peripheral driver that matches the specified path.
 192  */
 193 struct cam_periph *
 194 cam_periph_find(struct cam_path *path, char *name)
 195 {
 196         struct periph_driver **p_drv;
 197         struct cam_periph *periph;
 198
 199         SET_FOREACH(p_drv, periphdriver_set) {
 200                 if (name != NULL && (strcmp((*p_drv)->driver_name, name) != 0))
 201                         continue;
 202
 203                 crit_enter();
 204                 for (periph = TAILQ_FIRST(&(*p_drv)->units); periph != NULL;
 205                      periph = TAILQ_NEXT(periph, unit_links)) {
 206                         if (xpt_path_comp(periph->path, path) == 0) {
 207                                 crit_exit();
 208                                 return(periph);
 209                         }
 210                 }
 211                 crit_exit();
 212                 if (name != NULL)
 213                         return(NULL);
 214         }
 215         return(NULL);
 216 }
 217
 218 cam_status
 219 cam_periph_acquire(struct cam_periph *periph)
 220 {
 221         if (periph == NULL)
 222                 return(CAM_REQ_CMP_ERR);
 223
 224         crit_enter();
 225         periph->refcount++;
 226         crit_exit();
 227
 228         return(CAM_REQ_CMP);
 229 }
 230
 231 void
 232 cam_periph_release(struct cam_periph *periph)
 233 {
 234         if (periph == NULL)
 235                 return;
 236
 237         crit_enter();
 238         if ((--periph->refcount == 0)
 239          && (periph->flags & CAM_PERIPH_INVALID)) {
 240                 camperiphfree(periph);
 241         }
 242         crit_exit();
 243 }
 244
 245 /*
 246  * Look for the next unit number that is not currently in use for this
 247  * peripheral type starting at "newunit".  Also exclude unit numbers that
 248  * are reserved by for future "hardwiring" unless we already know that this
 249  * is a potential wired device.  Only assume that the device is "wired" the
 250  * first time through the loop since after that we'll be looking at unit
 251  * numbers that did not match a wiring entry.
 252  */
 253 static u_int
 254 camperiphnextunit(struct periph_driver *p_drv, u_int newunit, int wired,
 255                   path_id_t pathid, target_id_t target, lun_id_t lun)
 256 {
 257         struct  cam_periph *periph;
 258         char    *periph_name, *strval;
 259         int     i, val, dunit;
 260         const char *dname;
 261
 262         crit_enter();
 263         periph_name = p_drv->driver_name;
 264         for (;;newunit++) {
 265
 266                 for (periph = TAILQ_FIRST(&p_drv->units);
 267                      periph != NULL && periph->unit_number != newunit;
 268                      periph = TAILQ_NEXT(periph, unit_links))
 269                         ;
 270
 271                 if (periph != NULL && periph->unit_number == newunit) {
 272                         if (wired != 0) {
 273                                 xpt_print_path(periph->path);
 274                                 printf("Duplicate Wired Device entry!\n");
 275                                 xpt_print_path(periph->path);
 276                                 printf("Second device (%s device at scbus%d "
 277                                        "target %d lun %d) will not be wired\n",
 278                                        periph_name, pathid, target, lun);
 279                                 wired = 0;
 280                         }
 281                         continue;
 282                 }
 283                 if (wired)
 284                         break;
 285
 286                 /*
 287                  * Don't match entries like "da 4" as a wired down
 288                  * device, but do match entries like "da 4 target 5"
 289                  * or even "da 4 scbus 1".
 290                  */
 291                 i = -1;
 292                 while ((i = resource_locate(i, periph_name)) != -1) {
 293                         dname = resource_query_name(i);
 294                         dunit = resource_query_unit(i);
 295                         /* if no "target" and no specific scbus, skip */
 296                         if (resource_int_value(dname, dunit, "target", &val) &&
 297                             (resource_string_value(dname, dunit, "at",&strval)||
 298                              strcmp(strval, "scbus") == 0))
 299                                 continue;
 300                         if (newunit == dunit)
 301                                 break;
 302                 }
 303                 if (i == -1)
 304                         break;
 305         }
 306         crit_exit();
 307         return (newunit);
 308 }
 309
 310 static u_int
 311 camperiphunit(struct periph_driver *p_drv, path_id_t pathid,
 312               target_id_t target, lun_id_t lun)
 313 {
 314         u_int   unit;
 315         int     hit, i, val, dunit;
 316         const char *dname;
 317         char    pathbuf[32], *strval, *periph_name;
 318
 319         unit = 0;
 320
 321         periph_name = p_drv->driver_name;
 322         snprintf(pathbuf, sizeof(pathbuf), "scbus%d", pathid);
 323         i = -1;
 324         for (hit = 0; (i = resource_locate(i, periph_name)) != -1; hit = 0) {
 325                 dname = resource_query_name(i);
 326                 dunit = resource_query_unit(i);
 327                 if (resource_string_value(dname, dunit, "at", &strval) == 0) {
 328                         if (strcmp(strval, pathbuf) != 0)
 329                                 continue;
 330                         hit++;
 331                 }
 332                 if (resource_int_value(dname, dunit, "target", &val) == 0) {
 333                         if (val != target)
 334                                 continue;
 335                         hit++;
 336                 }
 337                 if (resource_int_value(dname, dunit, "lun", &val) == 0) {
 338                         if (val != lun)
 339                                 continue;
 340                         hit++;
 341                 }
 342                 if (hit != 0) {
 343                         unit = dunit;
 344                         break;
 345                 }
 346         }
 347
 348         /*
 349          * Either start from 0 looking for the next unit or from
 350          * the unit number given in the resource config.  This way,
 351          * if we have wildcard matches, we don't return the same
 352          * unit number twice.
 353          */
 354         unit = camperiphnextunit(p_drv, unit, /*wired*/hit, pathid,
 355                                  target, lun);
 356
 357         return (unit);
 358 }
 359
 360 void
 361 cam_periph_invalidate(struct cam_periph *periph)
 362 {
 363         /*
 364          * We only call this routine the first time a peripheral is
 365          * invalidated.  The oninvalidate() routine is always called in
 366          * a critical section.
 367          */
 368         crit_enter();
 369         if (((periph->flags & CAM_PERIPH_INVALID) == 0)
 370          && (periph->periph_oninval != NULL))
 371                 periph->periph_oninval(periph);
 372
 373         periph->flags |= CAM_PERIPH_INVALID;
 374         periph->flags &= ~CAM_PERIPH_NEW_DEV_FOUND;
 375
 376         if (periph->refcount == 0)
 377                 camperiphfree(periph);
 378         else if (periph->refcount < 0)
 379                 printf("cam_invalidate_periph: refcount < 0!!\n");
 380         crit_exit();
 381 }
 382
 383 static void
 384 camperiphfree(struct cam_periph *periph)
 385 {
 386         struct periph_driver **p_drv;
 387
 388         SET_FOREACH(p_drv, periphdriver_set) {
 389                 if (strcmp((*p_drv)->driver_name, periph->periph_name) == 0)
 390                         break;
 391         }
 392
 393         if (*p_drv == NULL) {
 394                 printf("camperiphfree: attempt to free "
 395                         "non-existant periph: %s\n", periph->periph_name);
 396                 return;
 397         }
 398
 399         if (periph->periph_dtor != NULL)
 400                 periph->periph_dtor(periph);
 401
 402         crit_enter();
 403         TAILQ_REMOVE(&(*p_drv)->units, periph, unit_links);
 404         (*p_drv)->generation++;
 405         crit_exit();
 406
 407         xpt_remove_periph(periph);
 408
 409         if (periph->flags & CAM_PERIPH_NEW_DEV_FOUND) {
 410                 union ccb ccb;
 411                 void *arg;
 412
 413                 switch (periph->deferred_ac) {
 414                 case AC_FOUND_DEVICE:
 415                         ccb.ccb_h.func_code = XPT_GDEV_TYPE;
 416                         xpt_setup_ccb(&ccb.ccb_h, periph->path, /*priority*/ 1);
 417                         xpt_action(&ccb);
 418                         arg = &ccb;
 419                         break;
 420                 case AC_PATH_REGISTERED:
 421                         ccb.ccb_h.func_code = XPT_PATH_INQ;
 422                         xpt_setup_ccb(&ccb.ccb_h, periph->path, /*priority*/ 1);
 423                         xpt_action(&ccb);
 424                         arg = &ccb;
 425                         break;
 426                 default:
 427                         arg = NULL;
 428                         break;
 429                 }
 430                 periph->deferred_callback(NULL, periph->deferred_ac,
 431                                           periph->path, arg);
 432         }
 433         xpt_free_path(periph->path);
 434         free(periph, M_DEVBUF);
 435 }
 436
 437 /*
 438  * Wait interruptibly for an exclusive lock.
 439  */
 440 int
 441 cam_periph_lock(struct cam_periph *periph, int flags)
 442 {
 443         int error;
 444
 445         while ((periph->flags & CAM_PERIPH_LOCKED) != 0) {
 446                 periph->flags |= CAM_PERIPH_LOCK_WANTED;
 447                 if ((error = tsleep(periph, flags, "caplck", 0)) != 0)
 448                         return error;
 449         }
 450
 451         if (cam_periph_acquire(periph) != CAM_REQ_CMP)
 452                 return(ENXIO);
 453
 454         periph->flags |= CAM_PERIPH_LOCKED;
 455         return 0;
 456 }
 457
 458 /*
 459  * Unlock and wake up any waiters.
 460  */
 461 void
 462 cam_periph_unlock(struct cam_periph *periph)
 463 {
 464         periph->flags &= ~CAM_PERIPH_LOCKED;
 465         if ((periph->flags & CAM_PERIPH_LOCK_WANTED) != 0) {
 466                 periph->flags &= ~CAM_PERIPH_LOCK_WANTED;
 467                 wakeup(periph);
 468         }
 469
 470         cam_periph_release(periph);
 471 }
 472
 473 /*
 474  * Map user virtual pointers into kernel virtual address space, so we can
 475  * access the memory.  This won't work on physical pointers, for now it's
 476  * up to the caller to check for that.  (XXX KDM -- should we do that here
 477  * instead?)  This also only works for up to MAXPHYS memory.  Since we use
 478  * buffers to map stuff in and out, we're limited to the buffer size.
 479  */
 480 int
 481 cam_periph_mapmem(union ccb *ccb, struct cam_periph_map_info *mapinfo)
 482 {
 483         int numbufs, i, j;
 484         int flags[CAM_PERIPH_MAXMAPS];
 485         u_int8_t **data_ptrs[CAM_PERIPH_MAXMAPS];
 486         u_int32_t lengths[CAM_PERIPH_MAXMAPS];
 487         u_int32_t dirs[CAM_PERIPH_MAXMAPS];
 488
 489         switch(ccb->ccb_h.func_code) {
 490         case XPT_DEV_MATCH:
 491                 if (ccb->cdm.match_buf_len == 0) {
 492                         printf("cam_periph_mapmem: invalid match buffer "
 493                                "length 0\n");
 494                         return(EINVAL);
 495                 }
 496                 if (ccb->cdm.pattern_buf_len > 0) {
 497                         data_ptrs[0] = (u_int8_t **)&ccb->cdm.patterns;
 498                         lengths[0] = ccb->cdm.pattern_buf_len;
 499                         dirs[0] = CAM_DIR_OUT;
 500                         data_ptrs[1] = (u_int8_t **)&ccb->cdm.matches;
 501                         lengths[1] = ccb->cdm.match_buf_len;
 502                         dirs[1] = CAM_DIR_IN;
 503                         numbufs = 2;
 504                 } else {
 505                         data_ptrs[0] = (u_int8_t **)&ccb->cdm.matches;
 506                         lengths[0] = ccb->cdm.match_buf_len;
 507                         dirs[0] = CAM_DIR_IN;
 508                         numbufs = 1;
 509                 }
 510                 break;
 511         case XPT_SCSI_IO:
 512         case XPT_CONT_TARGET_IO:
 513                 if ((ccb->ccb_h.flags & CAM_DIR_MASK) == CAM_DIR_NONE)
 514                         return(0);
 515
 516                 data_ptrs[0] = &ccb->csio.data_ptr;
 517                 lengths[0] = ccb->csio.dxfer_len;
 518                 dirs[0] = ccb->ccb_h.flags & CAM_DIR_MASK;
 519                 numbufs = 1;
 520                 break;
 521         default:
 522                 return(EINVAL);
 523                 break; /* NOTREACHED */
 524         }
 525
 526         /*
 527          * Check the transfer length and permissions first, so we don't
 528          * have to unmap any previously mapped buffers.
 529          */
 530         for (i = 0; i < numbufs; i++) {
 531
 532                 flags[i] = 0;
 533
 534                 /*
 535                  * The userland data pointer passed in may not be page
 536                  * aligned.  vmapbuf() truncates the address to a page
 537                  * boundary, so if the address isn't page aligned, we'll
 538                  * need enough space for the given transfer length, plus
 539                  * whatever extra space is necessary to make it to the page
 540                  * boundary.
 541                  */
 542                 if ((lengths[i] +
 543                     (((vm_offset_t)(*data_ptrs[i])) & PAGE_MASK)) > DFLTPHYS){
 544                         printf("cam_periph_mapmem: attempt to map %lu bytes, "
 545                                "which is greater than DFLTPHYS(%d)\n",
 546                                (long)(lengths[i] +
 547                                (((vm_offset_t)(*data_ptrs[i])) & PAGE_MASK)),
 548                                DFLTPHYS);
 549                         return(E2BIG);
 550                 }
 551
 552                 if (dirs[i] & CAM_DIR_OUT) {
 553                         flags[i] = B_WRITE;
 554                         if (!useracc(*data_ptrs[i], lengths[i],
 555                                      VM_PROT_READ)) {
 556                                 printf("cam_periph_mapmem: error, "
 557                                         "address %p, length %lu isn't "
 558                                         "user accessible for READ\n",
 559                                         (void *)*data_ptrs[i],
 560                                         (u_long)lengths[i]);
 561                                 return(EACCES);
 562                         }
 563                 }
 564
 565                 /*
 566                  * XXX this check is really bogus, since B_WRITE currently
 567                  * is all 0's, and so it is "set" all the time.
 568                  */
 569                 if (dirs[i] & CAM_DIR_IN) {
 570                         flags[i] |= B_READ;
 571                         if (!useracc(*data_ptrs[i], lengths[i],
 572                                      VM_PROT_WRITE)) {
 573                                 printf("cam_periph_mapmem: error, "
 574                                         "address %p, length %lu isn't "
 575                                         "user accessible for WRITE\n",
 576                                         (void *)*data_ptrs[i],
 577                                         (u_long)lengths[i]);
 578
 579                                 return(EACCES);
 580                         }
 581                 }
 582
 583         }
 584
 585         for (i = 0; i < numbufs; i++) {
 586                 /*
 587                  * Get the buffer.
 588                  */
 589                 mapinfo->bp[i] = getpbuf(NULL);
 590
 591                 /* save the buffer's data address */
 592                 mapinfo->bp[i]->b_saveaddr = mapinfo->bp[i]->b_data;
 593
 594                 /* put our pointer in the data slot */
 595                 mapinfo->bp[i]->b_data = *data_ptrs[i];
 596
 597                 /* set the transfer length, we know it's < DFLTPHYS */
 598                 mapinfo->bp[i]->b_bufsize = lengths[i];
 599
 600                 /* set the flags */
 601                 mapinfo->bp[i]->b_flags = flags[i];
 602
 603                 /* map the buffer into kernel memory */
 604                 if (vmapbuf(mapinfo->bp[i]) < 0) {
 605                         printf("cam_periph_mapmem: error, "
 606                                 "address %p, length %lu isn't "
 607                                 "user accessible any more\n",
 608                                 (void *)*data_ptrs[i],
 609                                 (u_long)lengths[i]);
 610                         for (j = 0; j < i; ++j) {
 611                                 *data_ptrs[j] = mapinfo->bp[j]->b_saveaddr;
 612                                 relpbuf(mapinfo->bp[j], NULL);
 613                         }
 614                         return(EACCES);
 615                 }
 616
 617                 /* set our pointer to the new mapped area */
 618                 *data_ptrs[i] = mapinfo->bp[i]->b_data;
 619
 620                 mapinfo->num_bufs_used++;
 621         }
 622
 623         return(0);
 624 }
 625
 626 /*
 627  * Unmap memory segments mapped into kernel virtual address space by
 628  * cam_periph_mapmem().
 629  */
 630 void
 631 cam_periph_unmapmem(union ccb *ccb, struct cam_periph_map_info *mapinfo)
 632 {
 633         int numbufs, i;
 634         u_int8_t **data_ptrs[CAM_PERIPH_MAXMAPS];
 635
 636         if (mapinfo->num_bufs_used <= 0) {
 637                 /* allow ourselves to be swapped once again */
 638                 return;
 639         }
 640
 641         switch (ccb->ccb_h.func_code) {
 642         case XPT_DEV_MATCH:
 643                 numbufs = min(mapinfo->num_bufs_used, 2);
 644
 645                 if (numbufs == 1) {
 646                         data_ptrs[0] = (u_int8_t **)&ccb->cdm.matches;
 647                 } else {
 648                         data_ptrs[0] = (u_int8_t **)&ccb->cdm.patterns;
 649                         data_ptrs[1] = (u_int8_t **)&ccb->cdm.matches;
 650                 }
 651                 break;
 652         case XPT_SCSI_IO:
 653         case XPT_CONT_TARGET_IO:
 654                 data_ptrs[0] = &ccb->csio.data_ptr;
 655                 numbufs = min(mapinfo->num_bufs_used, 1);
 656                 break;
 657         default:
 658                 /* allow ourselves to be swapped once again */
 659                 return;
 660                 break; /* NOTREACHED */
 661         }
 662
 663         for (i = 0; i < numbufs; i++) {
 664                 /* Set the user's pointer back to the original value */
 665                 *data_ptrs[i] = mapinfo->bp[i]->b_saveaddr;
 666
 667                 /* unmap the buffer */
 668                 vunmapbuf(mapinfo->bp[i]);
 669
 670                 /* release the buffer */
 671                 relpbuf(mapinfo->bp[i], NULL);
 672         }
 673
 674         /* allow ourselves to be swapped once again */
 675 }
 676
 677 union ccb *
 678 cam_periph_getccb(struct cam_periph *periph, u_int32_t priority)
 679 {
 680         struct ccb_hdr *ccb_h;
 681
 682         CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("entering cdgetccb\n"));
 683
 684         crit_enter();
 685
 686         while (periph->ccb_list.slh_first == NULL) {
 687                 if (periph->immediate_priority > priority)
 688                         periph->immediate_priority = priority;
 689                 xpt_schedule(periph, priority);
 690                 if ((periph->ccb_list.slh_first != NULL)
 691                  && (periph->ccb_list.slh_first->pinfo.priority == priority))
 692                         break;
 693                 tsleep(&periph->ccb_list, 0, "cgticb", 0);
 694         }
 695
 696         ccb_h = periph->ccb_list.slh_first;
 697         SLIST_REMOVE_HEAD(&periph->ccb_list, periph_links.sle);
 698         crit_exit();
 699         return ((union ccb *)ccb_h);
 700 }
 701
 702 void
 703 cam_periph_ccbwait(union ccb *ccb)
 704 {
 705         crit_enter();
 706         if ((ccb->ccb_h.pinfo.index != CAM_UNQUEUED_INDEX)
 707          || ((ccb->ccb_h.status & CAM_STATUS_MASK) == CAM_REQ_INPROG))
 708                 tsleep(&ccb->ccb_h.cbfcnp, 0, "cbwait", 0);
 709         crit_exit();
 710 }
 711
 712 int
 713 cam_periph_ioctl(struct cam_periph *periph, int cmd, caddr_t addr,
 714                  int (*error_routine)(union ccb *ccb,
 715                                       cam_flags camflags,
 716                                       u_int32_t sense_flags))
 717 {
 718         union ccb            *ccb;
 719         int                  error;
 720         int                  found;
 721
 722         error = found = 0;
 723
 724         switch(cmd){
 725         case CAMGETPASSTHRU:
 726                 ccb = cam_periph_getccb(periph, /* priority */ 1);
 727                 xpt_setup_ccb(&ccb->ccb_h,
 728                               ccb->ccb_h.path,
 729                               /*priority*/1);
 730                 ccb->ccb_h.func_code = XPT_GDEVLIST;
 731
 732                 /*
 733                  * Basically, the point of this is that we go through
 734                  * getting the list of devices, until we find a passthrough
 735                  * device.  In the current version of the CAM code, the
 736                  * only way to determine what type of device we're dealing
 737                  * with is by its name.
 738                  */
 739                 while (found == 0) {
 740                         ccb->cgdl.index = 0;
 741                         ccb->cgdl.status = CAM_GDEVLIST_MORE_DEVS;
 742                         while (ccb->cgdl.status == CAM_GDEVLIST_MORE_DEVS) {
 743
 744                                 /* we want the next device in the list */
 745                                 xpt_action(ccb);
 746                                 if (strncmp(ccb->cgdl.periph_name,
 747                                     "pass", 4) == 0){
 748                                         found = 1;
 749                                         break;
 750                                 }
 751                         }
 752                         if ((ccb->cgdl.status == CAM_GDEVLIST_LAST_DEVICE) &&
 753                             (found == 0)) {
 754                                 ccb->cgdl.periph_name[0] = '\0';
 755                                 ccb->cgdl.unit_number = 0;
 756                                 break;
 757                         }
 758                 }
 759
 760                 /* copy the result back out */
 761                 bcopy(ccb, addr, sizeof(union ccb));
 762
 763                 /* and release the ccb */
 764                 xpt_release_ccb(ccb);
 765
 766                 break;
 767         default:
 768                 error = ENOTTY;
 769                 break;
 770         }
 771         return(error);
 772 }
 773
 774 int
 775 cam_periph_runccb(union ccb *ccb,
 776                   int (*error_routine)(union ccb *ccb,
 777                                        cam_flags camflags,
 778                                        u_int32_t sense_flags),
 779                   cam_flags camflags, u_int32_t sense_flags,
 780                   struct devstat *ds)
 781 {
 782         int error;
 783
 784         error = 0;
 785
 786         /*
 787          * If the user has supplied a stats structure, and if we understand
 788          * this particular type of ccb, record the transaction start.
 789          */
 790         if ((ds != NULL) && (ccb->ccb_h.func_code == XPT_SCSI_IO))
 791                 devstat_start_transaction(ds);
 792
 793         xpt_action(ccb);
 794
 795         do {
 796                 cam_periph_ccbwait(ccb);
 797                 if ((ccb->ccb_h.status & CAM_STATUS_MASK) == CAM_REQ_CMP)
 798                         error = 0;
 799                 else if (error_routine != NULL)
 800                         error = (*error_routine)(ccb, camflags, sense_flags);
 801                 else
 802                         error = 0;
 803
 804         } while (error == ERESTART);
 805
 806         if ((ccb->ccb_h.status & CAM_DEV_QFRZN) != 0)
 807                 cam_release_devq(ccb->ccb_h.path,
 808                                  /* relsim_flags */0,
 809                                  /* openings */0,
 810                                  /* timeout */0,
 811                                  /* getcount_only */ FALSE);
 812
 813         if ((ds != NULL) && (ccb->ccb_h.func_code == XPT_SCSI_IO))
 814                 devstat_end_transaction(ds,
 815                                         ccb->csio.dxfer_len,
 816                                         ccb->csio.tag_action & 0xf,
 817                                         ((ccb->ccb_h.flags & CAM_DIR_MASK) ==
 818                                         CAM_DIR_NONE) ?  DEVSTAT_NO_DATA :
 819                                         (ccb->ccb_h.flags & CAM_DIR_OUT) ?
 820                                         DEVSTAT_WRITE :
 821                                         DEVSTAT_READ);
 822
 823         return(error);
 824 }
 825
 826 void
 827 cam_freeze_devq(struct cam_path *path)
 828 {
 829         struct ccb_hdr ccb_h;
 830
 831         xpt_setup_ccb(&ccb_h, path, /*priority*/1);
 832         ccb_h.func_code = XPT_NOOP;
 833         ccb_h.flags = CAM_DEV_QFREEZE;
 834         xpt_action((union ccb *)&ccb_h);
 835 }
 836
 837 u_int32_t
 838 cam_release_devq(struct cam_path *path, u_int32_t relsim_flags,
 839                  u_int32_t openings, u_int32_t timeout,
 840                  int getcount_only)
 841 {
 842         struct ccb_relsim crs;
 843
 844         xpt_setup_ccb(&crs.ccb_h, path,
 845                       /*priority*/1);
 846         crs.ccb_h.func_code = XPT_REL_SIMQ;
 847         crs.ccb_h.flags = getcount_only ? CAM_DEV_QFREEZE : 0;
 848         crs.release_flags = relsim_flags;
 849         crs.openings = openings;
 850         crs.release_timeout = timeout;
 851         xpt_action((union ccb *)&crs);
 852         return (crs.qfrozen_cnt);
 853 }
 854
 855 #define saved_ccb_ptr ppriv_ptr0
 856 static void
 857 camperiphdone(struct cam_periph *periph, union ccb *done_ccb)
 858 {
 859         cam_status      status;
 860         int             frozen;
 861         int             sense;
 862         struct scsi_start_stop_unit *scsi_cmd;
 863         u_int32_t       relsim_flags, timeout;
 864         u_int32_t       qfrozen_cnt;
 865
 866         status = done_ccb->ccb_h.status;
 867         frozen = (status & CAM_DEV_QFRZN) != 0;
 868         sense  = (status & CAM_AUTOSNS_VALID) != 0;
 869         status &= CAM_STATUS_MASK;
 870
 871         timeout = 0;
 872         relsim_flags = 0;
 873
 874         /*
 875          * Unfreeze the queue once if it is already frozen..
 876          */
 877         if (frozen != 0) {
 878                 qfrozen_cnt = cam_release_devq(done_ccb->ccb_h.path,
 879                                               /*relsim_flags*/0,
 880                                               /*openings*/0,
 881                                               /*timeout*/0,
 882                                               /*getcount_only*/0);
 883         }
 884
 885         switch (status) {
 886
 887         case CAM_REQ_CMP:
 888
 889                 /*
 890                  * If we have successfully taken a device from the not
 891                  * ready to ready state, re-scan the device and re-get the
 892                  * inquiry information.  Many devices (mostly disks) don't
 893                  * properly report their inquiry information unless they
 894                  * are spun up.
 895                  */
 896                 if (done_ccb->ccb_h.func_code == XPT_SCSI_IO) {
 897                         scsi_cmd = (struct scsi_start_stop_unit *)
 898                                         &done_ccb->csio.cdb_io.cdb_bytes;
 899
 900                         if (scsi_cmd->opcode == START_STOP_UNIT)
 901                                 xpt_async(AC_INQ_CHANGED,
 902                                           done_ccb->ccb_h.path, NULL);
 903                 }
 904                 bcopy(done_ccb->ccb_h.saved_ccb_ptr, done_ccb,
 905                       sizeof(union ccb));
 906
 907                 periph->flags &= ~CAM_PERIPH_RECOVERY_INPROG;
 908
 909                 xpt_action(done_ccb);
 910
 911                 break;
 912         case CAM_SCSI_STATUS_ERROR:
 913                 scsi_cmd = (struct scsi_start_stop_unit *)
 914                                 &done_ccb->csio.cdb_io.cdb_bytes;
 915                 if (sense != 0) {
 916                         struct scsi_sense_data *sense;
 917                         int    error_code, sense_key, asc, ascq;
 918
 919                         sense = &done_ccb->csio.sense_data;
 920                         scsi_extract_sense(sense, &error_code,
 921                                            &sense_key, &asc, &ascq);
 922
 923                         /*
 924                          * If the error is "invalid field in CDB",
 925                          * and the load/eject flag is set, turn the
 926                          * flag off and try again.  This is just in
 927                          * case the drive in question barfs on the
 928                          * load eject flag.  The CAM code should set
 929                          * the load/eject flag by default for
 930                          * removable media.
 931                          */
 932
 933                         /* XXX KDM
 934                          * Should we check to see what the specific
 935                          * scsi status is??  Or does it not matter
 936                          * since we already know that there was an
 937                          * error, and we know what the specific
 938                          * error code was, and we know what the
 939                          * opcode is..
 940                          */
 941                         if ((scsi_cmd->opcode == START_STOP_UNIT) &&
 942                             ((scsi_cmd->how & SSS_LOEJ) != 0) &&
 943                              (asc == 0x24) && (ascq == 0x00) &&
 944                              (done_ccb->ccb_h.retry_count > 0)) {
 945
 946                                 scsi_cmd->how &= ~SSS_LOEJ;
 947
 948                                 xpt_action(done_ccb);
 949
 950                         } else if (done_ccb->ccb_h.retry_count > 0) {
 951                                 /*
 952                                  * In this case, the error recovery
 953                                  * command failed, but we've got
 954                                  * some retries left on it.  Give
 955                                  * it another try.
 956                                  */
 957
 958                                 /* set the timeout to .5 sec */
 959                                 relsim_flags =
 960                                         RELSIM_RELEASE_AFTER_TIMEOUT;
 961                                 timeout = 500;
 962
 963                                 xpt_action(done_ccb);
 964
 965                                 break;
 966
 967                         } else {
 968                                 /*
 969                                  * Copy the original CCB back and
 970                                  * send it back to the caller.
 971                                  */
 972                                 bcopy(done_ccb->ccb_h.saved_ccb_ptr,
 973                                       done_ccb, sizeof(union ccb));
 974
 975                                 periph->flags &= ~CAM_PERIPH_RECOVERY_INPROG;
 976
 977                                 xpt_action(done_ccb);
 978                         }
 979                 } else {
 980                         /*
 981                          * Eh??  The command failed, but we don't
 982                          * have any sense.  What's up with that?
 983                          * Fire the CCB again to return it to the
 984                          * caller.
 985                          */
 986                         bcopy(done_ccb->ccb_h.saved_ccb_ptr,
 987                               done_ccb, sizeof(union ccb));
 988
 989                         periph->flags &= ~CAM_PERIPH_RECOVERY_INPROG;
 990
 991                         xpt_action(done_ccb);
 992
 993                 }
 994                 break;
 995         default:
 996                 bcopy(done_ccb->ccb_h.saved_ccb_ptr, done_ccb,
 997                       sizeof(union ccb));
 998
 999                 periph->flags &= ~CAM_PERIPH_RECOVERY_INPROG;
1000
1001                 xpt_action(done_ccb);
1002
1003                 break;
1004         }
1005
1006         /* decrement the retry count */
1007         if (done_ccb->ccb_h.retry_count > 0)
1008                 done_ccb->ccb_h.retry_count--;
1009
1010         qfrozen_cnt = cam_release_devq(done_ccb->ccb_h.path,
1011                                       /*relsim_flags*/relsim_flags,
1012                                       /*openings*/0,
1013                                       /*timeout*/timeout,
1014                                       /*getcount_only*/0);
1015 }
1016
1017 /*
1018  * Generic Async Event handler.  Peripheral drivers usually
1019  * filter out the events that require personal attention,
1020  * and leave the rest to this function.
1021  */
1022 void
1023 cam_periph_async(struct cam_periph *periph, u_int32_t code,
1024                  struct cam_path *path, void *arg)
1025 {
1026         switch (code) {
1027         case AC_LOST_DEVICE:
1028                 cam_periph_invalidate(periph);
1029                 break;
1030         case AC_SENT_BDR:
1031         case AC_BUS_RESET:
1032         {
1033                 cam_periph_bus_settle(periph, SCSI_DELAY);
1034                 break;
1035         }
1036         default:
1037                 break;
1038         }
1039 }
1040
1041 void
1042 cam_periph_bus_settle(struct cam_periph *periph, u_int bus_settle)
1043 {
1044         struct ccb_getdevstats cgds;
1045
1046         xpt_setup_ccb(&cgds.ccb_h, periph->path, /*priority*/1);
1047         cgds.ccb_h.func_code = XPT_GDEV_STATS;
1048         xpt_action((union ccb *)&cgds);
1049         cam_periph_freeze_after_event(periph, &cgds.last_reset, bus_settle);
1050 }
1051
1052 void
1053 cam_periph_freeze_after_event(struct cam_periph *periph,
1054                               struct timeval* event_time, u_int duration_ms)
1055 {
1056         struct timeval delta;
1057         struct timeval duration_tv;
1058
1059         microuptime(&delta);
1060         timevalsub(&delta, event_time);
1061         duration_tv.tv_sec = duration_ms / 1000;
1062         duration_tv.tv_usec = (duration_ms % 1000) * 1000;
1063         if (timevalcmp(&delta, &duration_tv, <)) {
1064                 timevalsub(&duration_tv, &delta);
1065
1066                 duration_ms = duration_tv.tv_sec * 1000;
1067                 duration_ms += duration_tv.tv_usec / 1000;
1068                 cam_freeze_devq(periph->path);
1069                 cam_release_devq(periph->path,
1070                                 RELSIM_RELEASE_AFTER_TIMEOUT,
1071                                 /*reduction*/0,
1072                                 /*timeout*/duration_ms,
1073                                 /*getcount_only*/0);
1074         }
1075
1076 }
1077
1078 /*
1079  * Generic error handler.  Peripheral drivers usually filter
1080  * out the errors that they handle in a unique mannor, then
1081  * call this function.
1082  */
1083 int
1084 cam_periph_error(union ccb *ccb, cam_flags camflags,
1085                  u_int32_t sense_flags, union ccb *save_ccb)
1086 {
1087         cam_status status;
1088         int        frozen;
1089         int        sense;
1090         int        error;
1091         int        openings;
1092         int        retry;
1093         u_int32_t  relsim_flags;
1094         u_int32_t  timeout;
1095
1096         status = ccb->ccb_h.status;
1097         frozen = (status & CAM_DEV_QFRZN) != 0;
1098         sense  = (status & CAM_AUTOSNS_VALID) != 0;
1099         status &= CAM_STATUS_MASK;
1100         relsim_flags = 0;
1101
1102         switch (status) {
1103         case CAM_REQ_CMP:
1104                 /* decrement the number of retries */
1105                 retry = ccb->ccb_h.retry_count > 0;
1106                 if (retry)
1107                         ccb->ccb_h.retry_count--;
1108                 error = 0;
1109                 break;
1110         case CAM_AUTOSENSE_FAIL:
1111         case CAM_SCSI_STATUS_ERROR:
1112
1113                 switch (ccb->csio.scsi_status) {
1114                 case SCSI_STATUS_OK:
1115                 case SCSI_STATUS_COND_MET:
1116                 case SCSI_STATUS_INTERMED:
1117                 case SCSI_STATUS_INTERMED_COND_MET:
1118                         error = 0;
1119                         break;
1120                 case SCSI_STATUS_CMD_TERMINATED:
1121                 case SCSI_STATUS_CHECK_COND:
1122                         if (sense != 0) {
1123                                 struct scsi_sense_data *sense;
1124                                 int    error_code, sense_key, asc, ascq;
1125                                 struct cam_periph *periph;
1126                                 scsi_sense_action err_action;
1127                                 struct ccb_getdev cgd;
1128
1129                                 sense = &ccb->csio.sense_data;
1130                                 scsi_extract_sense(sense, &error_code,
1131                                                    &sense_key, &asc, &ascq);
1132                                 periph = xpt_path_periph(ccb->ccb_h.path);
1133
1134                                 /*
1135                                  * Grab the inquiry data for this device.
1136                                  */
1137                                 xpt_setup_ccb(&cgd.ccb_h, ccb->ccb_h.path,
1138                                               /*priority*/ 1);
1139                                 cgd.ccb_h.func_code = XPT_GDEV_TYPE;
1140                                 xpt_action((union ccb *)&cgd);
1141
1142                                 err_action = scsi_error_action(asc, ascq,
1143                                                                &cgd.inq_data);
1144
1145                                 /*
1146                                  * Send a Test Unit Ready to the device.
1147                                  * If the 'many' flag is set, we send 120
1148                                  * test unit ready commands, one every half
1149                                  * second.  Otherwise, we just send one TUR.
1150                                  * We only want to do this if the retry
1151                                  * count has not been exhausted.
1152                                  */
1153                                 if (((err_action & SS_MASK) == SS_TUR)
1154                                  && save_ccb != NULL
1155                                  && ccb->ccb_h.retry_count > 0) {
1156
1157                                         /*
1158                                          * Since error recovery is already
1159                                          * in progress, don't attempt to
1160                                          * process this error.  It is probably
1161                                          * related to the error that caused
1162                                          * the currently active error recovery
1163                                          * action.  Also, we only have
1164                                          * space for one saved CCB, so if we
1165                                          * had two concurrent error recovery
1166                                          * actions, we would end up
1167                                          * over-writing one error recovery
1168                                          * CCB with another one.
1169                                          */
1170                                         if (periph->flags &
1171                                             CAM_PERIPH_RECOVERY_INPROG) {
1172                                                 error = ERESTART;
1173                                                 break;
1174                                         }
1175
1176                                         periph->flags |=
1177                                                 CAM_PERIPH_RECOVERY_INPROG;
1178
1179                                         /* decrement the number of retries */
1180                                         if ((err_action &
1181                                              SSQ_DECREMENT_COUNT) != 0) {
1182                                                 retry = 1;
1183                                                 ccb->ccb_h.retry_count--;
1184                                         }
1185
1186                                         bcopy(ccb, save_ccb, sizeof(*save_ccb));
1187
1188                                         /*
1189                                          * We retry this one every half
1190                                          * second for a minute.  If the
1191                                          * device hasn't become ready in a
1192                                          * minute's time, it's unlikely to
1193                                          * ever become ready.  If the table
1194                                          * doesn't specify SSQ_MANY, we can
1195                                          * only try this once.  Oh well.
1196                                          */
1197                                         if ((err_action & SSQ_MANY) != 0)
1198                                                 scsi_test_unit_ready(&ccb->csio,
1199                                                                /*retries*/120,
1200                                                                camperiphdone,
1201                                                                MSG_SIMPLE_Q_TAG,
1202                                                                SSD_FULL_SIZE,
1203                                                                /*timeout*/5000);
1204                                         else
1205                                                 scsi_test_unit_ready(&ccb->csio,
1206                                                                /*retries*/1,
1207                                                                camperiphdone,
1208                                                                MSG_SIMPLE_Q_TAG,
1209                                                                SSD_FULL_SIZE,
1210                                                                /*timeout*/5000);
1211
1212                                         /* release the queue after .5 sec.  */
1213                                         relsim_flags =
1214                                                 RELSIM_RELEASE_AFTER_TIMEOUT;
1215                                         timeout = 500;
1216                                         /*
1217                                          * Drop the priority to 0 so that
1218                                          * we are the first to execute.  Also
1219                                          * freeze the queue after this command
1220                                          * is sent so that we can restore the
1221                                          * old csio and have it queued in the
1222                                          * proper order before we let normal
1223                                          * transactions go to the drive.
1224                                          */
1225                                         ccb->ccb_h.pinfo.priority = 0;
1226                                         ccb->ccb_h.flags |= CAM_DEV_QFREEZE;
1227
1228                                         /*
1229                                          * Save a pointer to the original
1230                                          * CCB in the new CCB.
1231                                          */
1232                                         ccb->ccb_h.saved_ccb_ptr = save_ccb;
1233
1234                                         error = ERESTART;
1235                                 }
1236                                 /*
1237                                  * Send a start unit command to the device,
1238                                  * and then retry the command.  We only
1239                                  * want to do this if the retry count has
1240                                  * not been exhausted.  If the user
1241                                  * specified 0 retries, then we follow
1242                                  * their request and do not retry.
1243                                  */
1244                                 else if (((err_action & SS_MASK) == SS_START)
1245                                       && save_ccb != NULL
1246                                       && ccb->ccb_h.retry_count > 0) {
1247                                         int le;
1248
1249                                         /*
1250                                          * Only one error recovery action
1251                                          * at a time.  See above.
1252                                          */
1253                                         if (periph->flags &
1254                                             CAM_PERIPH_RECOVERY_INPROG) {
1255                                                 error = ERESTART;
1256                                                 break;
1257                                         }
1258
1259                                         periph->flags |=
1260                                                 CAM_PERIPH_RECOVERY_INPROG;
1261
1262                                         /* decrement the number of retries */
1263                                         retry = 1;
1264                                         ccb->ccb_h.retry_count--;
1265
1266                                         /*
1267                                          * Check for removable media and
1268                                          * set load/eject flag
1269                                          * appropriately.
1270                                          */
1271                                         if (SID_IS_REMOVABLE(&cgd.inq_data))
1272                                                 le = TRUE;
1273                                         else
1274                                                 le = FALSE;
1275
1276                                         /*
1277                                          * Attempt to start the drive up.
1278                                          *
1279                                          * Save the current ccb so it can
1280                                          * be restored and retried once the
1281                                          * drive is started up.
1282                                          */
1283                                         bcopy(ccb, save_ccb, sizeof(*save_ccb));
1284
1285                                         scsi_start_stop(&ccb->csio,
1286                                                         /*retries*/1,
1287                                                         camperiphdone,
1288                                                         MSG_SIMPLE_Q_TAG,
1289                                                         /*start*/TRUE,
1290                                                         /*load/eject*/le,
1291                                                         /*immediate*/FALSE,
1292                                                         SSD_FULL_SIZE,
1293                                                         /*timeout*/50000);
1294                                         /*
1295                                          * Drop the priority to 0 so that
1296                                          * we are the first to execute.  Also
1297                                          * freeze the queue after this command
1298                                          * is sent so that we can restore the
1299                                          * old csio and have it queued in the
1300                                          * proper order before we let normal
1301                                          * transactions go to the drive.
1302                                          */
1303                                         ccb->ccb_h.pinfo.priority = 0;
1304                                         ccb->ccb_h.flags |= CAM_DEV_QFREEZE;
1305
1306                                         /*
1307                                          * Save a pointer to the original
1308                                          * CCB in the new CCB.
1309                                          */
1310                                         ccb->ccb_h.saved_ccb_ptr = save_ccb;
1311
1312                                         error = ERESTART;
1313                                 } else if ((sense_flags & SF_RETRY_UA) != 0) {
1314                                         /*
1315                                          * XXX KDM this is a *horrible*
1316                                          * hack.
1317                                          */
1318                                         error = scsi_interpret_sense(ccb,
1319                                                                   sense_flags,
1320                                                                   &relsim_flags,
1321                                                                   &openings,
1322                                                                   &timeout,
1323                                                                   err_action);
1324                                 }
1325
1326                                 /*
1327                                  * Theoretically, this code should send a
1328                                  * test unit ready to the given device, and
1329                                  * if it returns and error, send a start
1330                                  * unit command.  Since we don't yet have
1331                                  * the capability to do two-command error
1332                                  * recovery, just send a start unit.
1333                                  * XXX KDM fix this!
1334                                  */
1335                                 else if (((err_action & SS_MASK) == SS_TURSTART)
1336                                       && save_ccb != NULL
1337                                       && ccb->ccb_h.retry_count > 0) {
1338                                         int le;
1339
1340                                         /*
1341                                          * Only one error recovery action
1342                                          * at a time.  See above.
1343                                          */
1344                                         if (periph->flags &
1345                                             CAM_PERIPH_RECOVERY_INPROG) {
1346                                                 error = ERESTART;
1347                                                 break;
1348                                         }
1349
1350                                         periph->flags |=
1351                                                 CAM_PERIPH_RECOVERY_INPROG;
1352
1353                                         /* decrement the number of retries */
1354                                         retry = 1;
1355                                         ccb->ccb_h.retry_count--;
1356
1357                                         /*
1358                                          * Check for removable media and
1359                                          * set load/eject flag
1360                                          * appropriately.
1361                                          */
1362                                         if (SID_IS_REMOVABLE(&cgd.inq_data))
1363                                                 le = TRUE;
1364                                         else
1365                                                 le = FALSE;
1366
1367                                         /*
1368                                          * Attempt to start the drive up.
1369                                          *
1370                                          * Save the current ccb so it can
1371                                          * be restored and retried once the
1372                                          * drive is started up.
1373                                          */
1374                                         bcopy(ccb, save_ccb, sizeof(*save_ccb));
1375
1376                                         scsi_start_stop(&ccb->csio,
1377                                                         /*retries*/1,
1378                                                         camperiphdone,
1379                                                         MSG_SIMPLE_Q_TAG,
1380                                                         /*start*/TRUE,
1381                                                         /*load/eject*/le,
1382                                                         /*immediate*/FALSE,
1383                                                         SSD_FULL_SIZE,
1384                                                         /*timeout*/50000);
1385
1386                                         /* release the queue after .5 sec.  */
1387                                         relsim_flags =
1388                                                 RELSIM_RELEASE_AFTER_TIMEOUT;
1389                                         timeout = 500;
1390                                         /*
1391                                          * Drop the priority to 0 so that
1392                                          * we are the first to execute.  Also
1393                                          * freeze the queue after this command
1394                                          * is sent so that we can restore the
1395                                          * old csio and have it queued in the
1396                                          * proper order before we let normal
1397                                          * transactions go to the drive.
1398                                          */
1399                                         ccb->ccb_h.pinfo.priority = 0;
1400                                         ccb->ccb_h.flags |= CAM_DEV_QFREEZE;
1401
1402                                         /*
1403                                          * Save a pointer to the original
1404                                          * CCB in the new CCB.
1405                                          */
1406                                         ccb->ccb_h.saved_ccb_ptr = save_ccb;
1407
1408                                         error = ERESTART;
1409                                 } else {
1410                                         error = scsi_interpret_sense(ccb,
1411                                                                   sense_flags,
1412                                                                   &relsim_flags,
1413                                                                   &openings,
1414                                                                   &timeout,
1415                                                                   err_action);
1416                                 }
1417                         } else if (ccb->csio.scsi_status ==
1418                                    SCSI_STATUS_CHECK_COND
1419                                 && status != CAM_AUTOSENSE_FAIL) {
1420                                 /* no point in decrementing the retry count */
1421                                 panic("cam_periph_error: scsi status of "
1422                                       "CHECK COND returned but no sense "
1423                                       "information is availible.  "
1424                                       "Controller should have returned "
1425                                       "CAM_AUTOSENSE_FAILED");
1426                                 /* NOTREACHED */
1427                                 error = EIO;
1428                         } else if (ccb->ccb_h.retry_count == 0) {
1429                                 /*
1430                                  * XXX KDM shouldn't there be a better
1431                                  * argument to return??
1432                                  */
1433                                 error = EIO;
1434                         } else {
1435                                 /* decrement the number of retries */
1436                                 retry = ccb->ccb_h.retry_count > 0;
1437                                 if (retry)
1438                                         ccb->ccb_h.retry_count--;
1439                                 /*
1440                                  * If it was aborted with no
1441                                  * clue as to the reason, just
1442                                  * retry it again.
1443                                  */
1444                                 error = ERESTART;
1445                         }
1446                         break;
1447                 case SCSI_STATUS_QUEUE_FULL:
1448                 {
1449                         /* no decrement */
1450                         struct ccb_getdevstats cgds;
1451
1452                         /*
1453                          * First off, find out what the current
1454                          * transaction counts are.
1455                          */
1456                         xpt_setup_ccb(&cgds.ccb_h,
1457                                       ccb->ccb_h.path,
1458                                       /*priority*/1);
1459                         cgds.ccb_h.func_code = XPT_GDEV_STATS;
1460                         xpt_action((union ccb *)&cgds);
1461
1462                         /*
1463                          * If we were the only transaction active, treat
1464                          * the QUEUE FULL as if it were a BUSY condition.
1465                          */
1466                         if (cgds.dev_active != 0) {
1467                                 int total_openings;
1468
1469                                 /*
1470                                  * Reduce the number of openings to
1471                                  * be 1 less than the amount it took
1472                                  * to get a queue full bounded by the
1473                                  * minimum allowed tag count for this
1474                                  * device.
1475                                  */
1476                                 total_openings =
1477                                     cgds.dev_active+cgds.dev_openings;
1478                                 openings = cgds.dev_active;
1479                                 if (openings < cgds.mintags)
1480                                         openings = cgds.mintags;
1481                                 if (openings < total_openings)
1482                                         relsim_flags = RELSIM_ADJUST_OPENINGS;
1483                                 else {
1484                                         /*
1485                                          * Some devices report queue full for
1486                                          * temporary resource shortages.  For
1487                                          * this reason, we allow a minimum
1488                                          * tag count to be entered via a
1489                                          * quirk entry to prevent the queue
1490                                          * count on these devices from falling
1491                                          * to a pessimisticly low value.  We
1492                                          * still wait for the next successful
1493                                          * completion, however, before queueing
1494                                          * more transactions to the device.
1495                                          */
1496                                         relsim_flags =
1497                                             RELSIM_RELEASE_AFTER_CMDCMPLT;
1498                                 }
1499                                 timeout = 0;
1500                                 error = ERESTART;
1501                                 break;
1502                         }
1503                         /* FALLTHROUGH */
1504                 }
1505                 case SCSI_STATUS_BUSY:
1506                         /*
1507                          * Restart the queue after either another
1508                          * command completes or a 1 second timeout.
1509                          * If we have any retries left, that is.
1510                          */
1511                         retry = ccb->ccb_h.retry_count > 0;
1512                         if (retry) {
1513                                 ccb->ccb_h.retry_count--;
1514                                 error = ERESTART;
1515                                 relsim_flags = RELSIM_RELEASE_AFTER_TIMEOUT
1516                                              | RELSIM_RELEASE_AFTER_CMDCMPLT;
1517                                 timeout = 1000;
1518                         } else {
1519                                 error = EIO;
1520                         }
1521                         break;
1522                 case SCSI_STATUS_RESERV_CONFLICT:
1523                         error = EIO;
1524                         break;
1525                 default:
1526                         error = EIO;
1527                         break;
1528                 }
1529                 break;
1530         case CAM_REQ_CMP_ERR:
1531         case CAM_CMD_TIMEOUT:
1532         case CAM_UNEXP_BUSFREE:
1533         case CAM_UNCOR_PARITY:
1534         case CAM_DATA_RUN_ERR:
1535                 /* decrement the number of retries */
1536                 retry = ccb->ccb_h.retry_count > 0;
1537                 if (retry) {
1538                         ccb->ccb_h.retry_count--;
1539                         error = ERESTART;
1540                 } else {
1541                         error = EIO;
1542                 }
1543                 break;
1544         case CAM_UA_ABORT:
1545         case CAM_UA_TERMIO:
1546         case CAM_MSG_REJECT_REC:
1547                 /* XXX Don't know that these are correct */
1548                 error = EIO;
1549                 break;
1550         case CAM_SEL_TIMEOUT:
1551         {
1552                 /*
1553                  * XXX
1554                  * A single selection timeout should not be enough
1555                  * to invalidate a device.  We should retry for multiple
1556                  * seconds assuming this isn't a probe.  We'll probably
1557                  * need a special flag for that.
1558                  */
1559 #if 0
1560                 struct cam_path *newpath;
1561
1562                 /* Should we do more if we can't create the path?? */
1563                 if (xpt_create_path(&newpath, xpt_path_periph(ccb->ccb_h.path),
1564                                     xpt_path_path_id(ccb->ccb_h.path),
1565                                     xpt_path_target_id(ccb->ccb_h.path),
1566                                     CAM_LUN_WILDCARD) != CAM_REQ_CMP)
1567                         break;
1568                 /*
1569                  * Let peripheral drivers know that this device has gone
1570                  * away.
1571                  */
1572                 xpt_async(AC_LOST_DEVICE, newpath, NULL);
1573                 xpt_free_path(newpath);
1574 #endif
1575                 if ((sense_flags & SF_RETRY_SELTO) != 0) {
1576                         retry = ccb->ccb_h.retry_count > 0;
1577                         if (retry) {
1578                                 ccb->ccb_h.retry_count--;
1579                                 error = ERESTART;
1580                                 /*
1581                                  * Wait half a second to give the device
1582                                  * time to recover before we try again.
1583                                  */
1584                                 relsim_flags = RELSIM_RELEASE_AFTER_TIMEOUT;
1585                                 timeout = 500;
1586                         } else {
1587                                 error = ENXIO;
1588                         }
1589                 } else {
1590                         error = ENXIO;
1591                 }
1592                 break;
1593         }
1594         case CAM_REQ_INVALID:
1595         case CAM_PATH_INVALID:
1596         case CAM_DEV_NOT_THERE:
1597         case CAM_NO_HBA:
1598         case CAM_PROVIDE_FAIL:
1599         case CAM_REQ_TOO_BIG:
1600                 error = EINVAL;
1601                 break;
1602         case CAM_SCSI_BUS_RESET:
1603         case CAM_BDR_SENT:
1604         case CAM_REQUEUE_REQ:
1605                 /* Unconditional requeue, dammit */
1606                 error = ERESTART;
1607                 break;
1608         case CAM_RESRC_UNAVAIL:
1609         case CAM_BUSY:
1610                 /* timeout??? */
1611         default:
1612                 /* decrement the number of retries */
1613                 retry = ccb->ccb_h.retry_count > 0;
1614                 if (retry) {
1615                         ccb->ccb_h.retry_count--;
1616                         error = ERESTART;
1617                 } else {
1618                         /* Check the sense codes */
1619                         error = EIO;
1620                 }
1621                 break;
1622         }
1623
1624         /* Attempt a retry */
1625         if (error == ERESTART || error == 0) {
1626                 if (frozen != 0)
1627                         ccb->ccb_h.status &= ~CAM_DEV_QFRZN;
1628
1629                 if (error == ERESTART)
1630                         xpt_action(ccb);
1631
1632                 if (frozen != 0) {
1633                         cam_release_devq(ccb->ccb_h.path,
1634                                          relsim_flags,
1635                                          openings,
1636                                          timeout,
1637                                          /*getcount_only*/0);
1638                 }
1639         }
1640
1641
1642         return (error);
1643 }