sys/dev/ata/ata-queue.c

   1 /*-
   2  * Copyright (c) 1998 - 2008 Søren Schmidt <sos@FreeBSD.org>
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer,
  10  *    without modification, immediately at the beginning of the file.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  25  */
  26
  27 #include <sys/cdefs.h>
  28 __FBSDID("$FreeBSD$");
  29
  30 #include "opt_ata.h"
  31 #include <sys/param.h>
  32 #include <sys/systm.h>
  33 #include <sys/ata.h>
  34 #include <sys/kernel.h>
  35 #include <sys/bio.h>
  36 #include <sys/bus.h>
  37 #include <sys/conf.h>
  38 #include <sys/sema.h>
  39 #include <sys/taskqueue.h>
  40 #include <vm/uma.h>
  41 #include <machine/bus.h>
  42 #include <sys/rman.h>
  43 #include <dev/ata/ata-all.h>
  44 #include <ata_if.h>
  45
  46 /* prototypes */
  47 static void ata_completed(void *, int);
  48 static void ata_sort_queue(struct ata_channel *ch, struct ata_request *request);
  49 static char *ata_skey2str(u_int8_t);
  50
  51 void
  52 ata_queue_request(struct ata_request *request)
  53 {
  54     struct ata_channel *ch;
  55
  56     /* treat request as virgin (this might be an ATA_R_REQUEUE) */
  57     request->result = request->status = request->error = 0;
  58
  59     /* check that the device is still valid */
  60     if (!(request->parent = device_get_parent(request->dev))) {
  61         request->result = ENXIO;
  62         if (request->callback)
  63             (request->callback)(request);
  64         return;
  65     }
  66     ch = device_get_softc(request->parent);
  67     callout_init_mtx(&request->callout, &ch->state_mtx, CALLOUT_RETURNUNLOCKED);
  68     if (!request->callback && !(request->flags & ATA_R_REQUEUE))
  69         sema_init(&request->done, 0, "ATA request done");
  70
  71     /* in ATA_STALL_QUEUE state we call HW directly */
  72     if ((ch->state & ATA_STALL_QUEUE) && (request->flags & ATA_R_CONTROL)) {
  73         mtx_lock(&ch->state_mtx);
  74         ch->running = request;
  75         if (ch->hw.begin_transaction(request) == ATA_OP_FINISHED) {
  76             ch->running = NULL;
  77             if (!request->callback)
  78                 sema_destroy(&request->done);
  79             mtx_unlock(&ch->state_mtx);
  80             return;
  81         }
  82         mtx_unlock(&ch->state_mtx);
  83     }
  84     /* otherwise put request on the locked queue at the specified location */
  85     else  {
  86         mtx_lock(&ch->queue_mtx);
  87         if (request->flags & ATA_R_AT_HEAD)
  88             TAILQ_INSERT_HEAD(&ch->ata_queue, request, chain);
  89         else if (request->flags & ATA_R_ORDERED)
  90             ata_sort_queue(ch, request);
  91         else
  92             TAILQ_INSERT_TAIL(&ch->ata_queue, request, chain);
  93         mtx_unlock(&ch->queue_mtx);
  94         ATA_DEBUG_RQ(request, "queued");
  95         ata_start(ch->dev);
  96     }
  97
  98     /* if this is a requeued request callback/sleep we're done */
  99     if (request->flags & ATA_R_REQUEUE)
 100         return;
 101
 102     /* if this is not a callback wait until request is completed */
 103     if (!request->callback) {
 104         ATA_DEBUG_RQ(request, "wait for completion");
 105         if (!dumping &&
 106             sema_timedwait(&request->done, request->timeout * hz * 4)) {
 107             device_printf(request->dev,
 108                           "WARNING - %s taskqueue timeout "
 109                           "- completing request directly\n",
 110                           ata_cmd2str(request));
 111             request->flags |= ATA_R_DANGER1;
 112             ata_completed(request, 0);
 113         }
 114         sema_destroy(&request->done);
 115     }
 116 }
 117
 118 int
 119 ata_controlcmd(device_t dev, u_int8_t command, u_int16_t feature,
 120                u_int64_t lba, u_int16_t count)
 121 {
 122     struct ata_request *request = ata_alloc_request();
 123     int error = ENOMEM;
 124
 125     if (request) {
 126         request->dev = dev;
 127         request->u.ata.command = command;
 128         request->u.ata.lba = lba;
 129         request->u.ata.count = count;
 130         request->u.ata.feature = feature;
 131         request->flags = ATA_R_CONTROL;
 132         request->timeout = 1;
 133         request->retries = 0;
 134         ata_queue_request(request);
 135         error = request->result;
 136         ata_free_request(request);
 137     }
 138     return error;
 139 }
 140
 141 int
 142 ata_atapicmd(device_t dev, u_int8_t *ccb, caddr_t data,
 143              int count, int flags, int timeout)
 144 {
 145     struct ata_request *request = ata_alloc_request();
 146     struct ata_device *atadev = device_get_softc(dev);
 147     int error = ENOMEM;
 148
 149     if (request) {
 150         request->dev = dev;
 151         if ((atadev->param.config & ATA_PROTO_MASK) == ATA_PROTO_ATAPI_12)
 152             bcopy(ccb, request->u.atapi.ccb, 12);
 153         else
 154             bcopy(ccb, request->u.atapi.ccb, 16);
 155         request->data = data;
 156         request->bytecount = count;
 157         request->transfersize = min(request->bytecount, 65534);
 158         request->flags = flags | ATA_R_ATAPI;
 159         request->timeout = timeout;
 160         request->retries = 0;
 161         ata_queue_request(request);
 162         error = request->result;
 163         ata_free_request(request);
 164     }
 165     return error;
 166 }
 167
 168 void
 169 ata_start(device_t dev)
 170 {
 171     struct ata_channel *ch = device_get_softc(dev);
 172     struct ata_request *request;
 173     struct ata_composite *cptr;
 174     int dependencies = 0;
 175
 176     /* if we have a request on the queue try to get it running */
 177     mtx_lock(&ch->queue_mtx);
 178     if ((request = TAILQ_FIRST(&ch->ata_queue))) {
 179
 180         /* we need the locking function to get the lock for this channel */
 181         if (ATA_LOCKING(dev, ATA_LF_LOCK) == ch->unit) {
 182
 183             /* check for composite dependencies */
 184             if ((cptr = request->composite)) {
 185                 mtx_lock(&cptr->lock);
 186                 if ((request->flags & ATA_R_WRITE) &&
 187                     (cptr->wr_depend & cptr->rd_done) != cptr->wr_depend) {
 188                     dependencies = 1;
 189                 }
 190                 mtx_unlock(&cptr->lock);
 191             }
 192
 193             /* check we are in the right state and has no dependencies */
 194             mtx_lock(&ch->state_mtx);
 195             if (ch->state == ATA_IDLE && !dependencies) {
 196                 ATA_DEBUG_RQ(request, "starting");
 197                 TAILQ_REMOVE(&ch->ata_queue, request, chain);
 198                 ch->running = request;
 199                 ch->state = ATA_ACTIVE;
 200
 201                 /* if we are the freezing point release it */
 202                 if (ch->freezepoint == request)
 203                     ch->freezepoint = NULL;
 204
 205                 if (ch->hw.begin_transaction(request) == ATA_OP_FINISHED) {
 206                     ch->running = NULL;
 207                     ch->state = ATA_IDLE;
 208                     mtx_unlock(&ch->state_mtx);
 209                     mtx_unlock(&ch->queue_mtx);
 210                     ATA_LOCKING(dev, ATA_LF_UNLOCK);
 211                     ata_finish(request);
 212                     return;
 213                 }
 214                 if (dumping) {
 215                     mtx_unlock(&ch->state_mtx);
 216                     mtx_unlock(&ch->queue_mtx);
 217                     while (!ata_interrupt(ch))
 218                         DELAY(10);
 219                     return;
 220                 }
 221             }
 222             mtx_unlock(&ch->state_mtx);
 223         }
 224     }
 225     mtx_unlock(&ch->queue_mtx);
 226 }
 227
 228 void
 229 ata_finish(struct ata_request *request)
 230 {
 231     struct ata_channel *ch = device_get_softc(request->parent);
 232
 233     /*
 234      * if in ATA_STALL_QUEUE state or request has ATA_R_DIRECT flags set
 235      * we need to call ata_complete() directly here (no taskqueue involvement)
 236      */
 237     if (dumping ||
 238         (ch->state & ATA_STALL_QUEUE) || (request->flags & ATA_R_DIRECT)) {
 239         ATA_DEBUG_RQ(request, "finish directly");
 240         ata_completed(request, 0);
 241     }
 242     else {
 243         /* put request on the proper taskqueue for completion */
 244         if (request->bio && !(request->flags & (ATA_R_THREAD | ATA_R_TIMEOUT))){
 245             ATA_DEBUG_RQ(request, "finish bio_taskqueue");
 246             bio_taskqueue(request->bio, (bio_task_t *)ata_completed, request);
 247         }
 248         else {
 249             TASK_INIT(&request->task, 0, ata_completed, request);
 250             ATA_DEBUG_RQ(request, "finish taskqueue_swi");
 251             taskqueue_enqueue(taskqueue_swi, &request->task);
 252         }
 253     }
 254 }
 255
 256 static void
 257 ata_completed(void *context, int dummy)
 258 {
 259     struct ata_request *request = (struct ata_request *)context;
 260     struct ata_channel *ch = device_get_softc(request->parent);
 261     struct ata_device *atadev = device_get_softc(request->dev);
 262     struct ata_composite *composite;
 263
 264     if (request->flags & ATA_R_DANGER2) {
 265         device_printf(request->dev,
 266                       "WARNING - %s freeing taskqueue zombie request\n",
 267                       ata_cmd2str(request));
 268         request->flags &= ~(ATA_R_DANGER1 | ATA_R_DANGER2);
 269         ata_free_request(request);
 270         return;
 271     }
 272     if (request->flags & ATA_R_DANGER1)
 273         request->flags |= ATA_R_DANGER2;
 274
 275     ATA_DEBUG_RQ(request, "completed entered");
 276
 277     /* if we had a timeout, reinit channel and deal with the falldown */
 278     if (request->flags & ATA_R_TIMEOUT) {
 279         /*
 280          * if the channel is still present and
 281          * reinit succeeds and
 282          * the device doesn't get detached and
 283          * there are retries left we reinject this request
 284          */
 285         if (ch && !ata_reinit(ch->dev) && !request->result &&
 286             (request->retries-- > 0)) {
 287             if (!(request->flags & ATA_R_QUIET)) {
 288                 device_printf(request->dev,
 289                               "TIMEOUT - %s retrying (%d retr%s left)",
 290                               ata_cmd2str(request), request->retries,
 291                               request->retries == 1 ? "y" : "ies");
 292                 if (!(request->flags & (ATA_R_ATAPI | ATA_R_CONTROL)))
 293                     printf(" LBA=%ju", request->u.ata.lba);
 294                 printf("\n");
 295             }
 296             request->flags &= ~(ATA_R_TIMEOUT | ATA_R_DEBUG);
 297             request->flags |= (ATA_R_AT_HEAD | ATA_R_REQUEUE);
 298             ATA_DEBUG_RQ(request, "completed reinject");
 299             ata_queue_request(request);
 300             return;
 301         }
 302
 303         /* ran out of good intentions so finish with error */
 304         if (!request->result) {
 305             if (!(request->flags & ATA_R_QUIET)) {
 306                 if (request->dev) {
 307                     device_printf(request->dev, "FAILURE - %s timed out",
 308                                   ata_cmd2str(request));
 309                     if (!(request->flags & (ATA_R_ATAPI | ATA_R_CONTROL)))
 310                         printf(" LBA=%ju", request->u.ata.lba);
 311                     printf("\n");
 312                 }
 313             }
 314             request->result = EIO;
 315         }
 316     }
 317     else if (!(request->flags & ATA_R_ATAPI) ){
 318         /* if this is a soft ECC error warn about it */
 319         /* XXX SOS we could do WARF here */
 320         if ((request->status & (ATA_S_CORR | ATA_S_ERROR)) == ATA_S_CORR) {
 321             device_printf(request->dev,
 322                           "WARNING - %s soft error (ECC corrected)",
 323                           ata_cmd2str(request));
 324             if (!(request->flags & (ATA_R_ATAPI | ATA_R_CONTROL)))
 325                 printf(" LBA=%ju", request->u.ata.lba);
 326             printf("\n");
 327         }
 328
 329         /* if this is a UDMA CRC error we reinject if there are retries left */
 330         if (request->flags & ATA_R_DMA && request->error & ATA_E_ICRC) {
 331             if (request->retries-- > 0) {
 332                 device_printf(request->dev,
 333                               "WARNING - %s UDMA ICRC error (retrying request)",
 334                               ata_cmd2str(request));
 335                 if (!(request->flags & (ATA_R_ATAPI | ATA_R_CONTROL)))
 336                     printf(" LBA=%ju", request->u.ata.lba);
 337                 printf("\n");
 338                 request->flags |= (ATA_R_AT_HEAD | ATA_R_REQUEUE);
 339                 ata_queue_request(request);
 340                 return;
 341             }
 342         }
 343     }
 344
 345     switch (request->flags & ATA_R_ATAPI) {
 346
 347     /* ATA errors */
 348     default:
 349         if (!request->result && request->status & ATA_S_ERROR) {
 350             if (!(request->flags & ATA_R_QUIET)) {
 351                 device_printf(request->dev,
 352                               "FAILURE - %s status=%b error=%b",
 353                               ata_cmd2str(request),
 354                               request->status, "\20\10BUSY\7READY\6DMA_READY"
 355                               "\5DSC\4DRQ\3CORRECTABLE\2INDEX\1ERROR",
 356                               request->error, "\20\10ICRC\7UNCORRECTABLE"
 357                               "\6MEDIA_CHANGED\5NID_NOT_FOUND"
 358                               "\4MEDIA_CHANGE_REQEST"
 359                               "\3ABORTED\2NO_MEDIA\1ILLEGAL_LENGTH");
 360                 if ((request->flags & ATA_R_DMA) &&
 361                     (request->dma->status & ATA_BMSTAT_ERROR))
 362                     printf(" dma=0x%02x", request->dma->status);
 363                 if (!(request->flags & (ATA_R_ATAPI | ATA_R_CONTROL)))
 364                     printf(" LBA=%ju", request->u.ata.lba);
 365                 printf("\n");
 366             }
 367             request->result = EIO;
 368         }
 369         break;
 370
 371     /* ATAPI errors */
 372     case ATA_R_ATAPI:
 373         /* skip if result already set */
 374         if (request->result)
 375             break;
 376
 377         /* if we have a sensekey -> request sense from device */
 378         if ((request->error & ATA_E_ATAPI_SENSE_MASK) &&
 379             (request->u.atapi.ccb[0] != ATAPI_REQUEST_SENSE)) {
 380             static u_int8_t ccb[16] = { ATAPI_REQUEST_SENSE, 0, 0, 0,
 381                                         sizeof(struct atapi_sense),
 382                                         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
 383
 384             request->u.atapi.saved_cmd = request->u.atapi.ccb[0];
 385             bcopy(ccb, request->u.atapi.ccb, 16);
 386             request->data = (caddr_t)&request->u.atapi.sense;
 387             request->bytecount = sizeof(struct atapi_sense);
 388             request->donecount = 0;
 389             request->transfersize = sizeof(struct atapi_sense);
 390             request->timeout = 5;
 391             request->flags &= (ATA_R_ATAPI | ATA_R_QUIET | ATA_R_DEBUG);
 392             request->flags |= (ATA_R_READ | ATA_R_AT_HEAD | ATA_R_REQUEUE);
 393             ATA_DEBUG_RQ(request, "autoissue request sense");
 394             ata_queue_request(request);
 395             return;
 396         }
 397
 398         switch (request->u.atapi.sense.key & ATA_SENSE_KEY_MASK) {
 399         case ATA_SENSE_RECOVERED_ERROR:
 400             device_printf(request->dev, "WARNING - %s recovered error\n",
 401                           ata_cmd2str(request));
 402             /* FALLTHROUGH */
 403
 404         case ATA_SENSE_NO_SENSE:
 405             request->result = 0;
 406             break;
 407
 408         case ATA_SENSE_NOT_READY:
 409             request->result = EBUSY;
 410             break;
 411
 412         case ATA_SENSE_UNIT_ATTENTION:
 413             atadev->flags |= ATA_D_MEDIA_CHANGED;
 414             request->result = EIO;
 415             break;
 416
 417         default:
 418             request->result = EIO;
 419             if (request->flags & ATA_R_QUIET)
 420                 break;
 421
 422             device_printf(request->dev,
 423                           "FAILURE - %s %s asc=0x%02x ascq=0x%02x ",
 424                           ata_cmd2str(request), ata_skey2str(
 425                           (request->u.atapi.sense.key & ATA_SENSE_KEY_MASK)),
 426                           request->u.atapi.sense.asc,
 427                           request->u.atapi.sense.ascq);
 428             if (request->u.atapi.sense.specific & ATA_SENSE_SPEC_VALID)
 429                 printf("sks=0x%02x 0x%02x 0x%02x\n",
 430                        request->u.atapi.sense.specific & ATA_SENSE_SPEC_MASK,
 431                        request->u.atapi.sense.specific1,
 432                        request->u.atapi.sense.specific2);
 433             else
 434                 printf("\n");
 435         }
 436
 437         if ((request->u.atapi.sense.key & ATA_SENSE_KEY_MASK ?
 438              request->u.atapi.sense.key & ATA_SENSE_KEY_MASK :
 439              request->error))
 440             request->result = EIO;
 441     }
 442
 443     ATA_DEBUG_RQ(request, "completed callback/wakeup");
 444
 445     /* if we are part of a composite operation we need to maintain progress */
 446     if ((composite = request->composite)) {
 447         int index = 0;
 448
 449         mtx_lock(&composite->lock);
 450
 451         /* update whats done */
 452         if (request->flags & ATA_R_READ)
 453             composite->rd_done |= (1 << request->this);
 454         if (request->flags & ATA_R_WRITE)
 455             composite->wr_done |= (1 << request->this);
 456
 457         /* find ready to go dependencies */
 458         if (composite->wr_depend &&
 459             (composite->rd_done & composite->wr_depend)==composite->wr_depend &&
 460             (composite->wr_needed & (~composite->wr_done))) {
 461             index = composite->wr_needed & ~composite->wr_done;
 462         }
 463
 464         mtx_unlock(&composite->lock);
 465
 466         /* if we have any ready candidates kick them off */
 467         if (index) {
 468             int bit;
 469
 470             for (bit = 0; bit < MAX_COMPOSITES; bit++) {
 471                 if (index & (1 << bit))
 472                     ata_start(device_get_parent(composite->request[bit]->dev));
 473             }
 474         }
 475     }
 476
 477     /* get results back to the initiator for this request */
 478     if (request->callback)
 479         (request->callback)(request);
 480     else
 481         sema_post(&request->done);
 482
 483     /* only call ata_start if channel is present */
 484     if (ch)
 485         ata_start(ch->dev);
 486 }
 487
 488 void
 489 ata_timeout(struct ata_request *request)
 490 {
 491     struct ata_channel *ch = device_get_softc(request->parent);
 492
 493     //request->flags |= ATA_R_DEBUG;
 494     ATA_DEBUG_RQ(request, "timeout");
 495
 496     /*
 497      * if we have an ATA_ACTIVE request running, we flag the request
 498      * ATA_R_TIMEOUT so ata_finish will handle it correctly
 499      * also NULL out the running request so we wont loose
 500      * the race with an eventual interrupt arriving late
 501      */
 502     if (ch->state == ATA_ACTIVE) {
 503         request->flags |= ATA_R_TIMEOUT;
 504         mtx_unlock(&ch->state_mtx);
 505         ATA_LOCKING(ch->dev, ATA_LF_UNLOCK);
 506         ch->dma.unload(request);
 507         ata_finish(request);
 508     }
 509     else {
 510         mtx_unlock(&ch->state_mtx);
 511     }
 512 }
 513
 514 void
 515 ata_fail_requests(device_t dev)
 516 {
 517     struct ata_channel *ch = device_get_softc(device_get_parent(dev));
 518     struct ata_request *request, *tmp;
 519     TAILQ_HEAD(, ata_request) fail_requests;
 520     TAILQ_INIT(&fail_requests);
 521
 522     /* grap all channel locks to avoid races */
 523     mtx_lock(&ch->queue_mtx);
 524     mtx_lock(&ch->state_mtx);
 525
 526     /* do we have any running request to care about ? */
 527     if ((request = ch->running) && (!dev || request->dev == dev)) {
 528         callout_stop(&request->callout);
 529         ch->running = NULL;
 530         request->result = ENXIO;
 531         TAILQ_INSERT_TAIL(&fail_requests, request, chain);
 532     }
 533
 534     /* fail all requests queued on this channel for device dev if !NULL */
 535     TAILQ_FOREACH_SAFE(request, &ch->ata_queue, chain, tmp) {
 536         if (!dev || request->dev == dev) {
 537             TAILQ_REMOVE(&ch->ata_queue, request, chain);
 538             request->result = ENXIO;
 539             TAILQ_INSERT_TAIL(&fail_requests, request, chain);
 540         }
 541     }
 542
 543     mtx_unlock(&ch->state_mtx);
 544     mtx_unlock(&ch->queue_mtx);
 545
 546     /* finish up all requests collected above */
 547     TAILQ_FOREACH_SAFE(request, &fail_requests, chain, tmp) {
 548         TAILQ_REMOVE(&fail_requests, request, chain);
 549         ata_finish(request);
 550     }
 551 }
 552
 553 static u_int64_t
 554 ata_get_lba(struct ata_request *request)
 555 {
 556     if (request->flags & ATA_R_ATAPI) {
 557         switch (request->u.atapi.ccb[0]) {
 558         case ATAPI_READ_BIG:
 559         case ATAPI_WRITE_BIG:
 560         case ATAPI_READ_CD:
 561             return (request->u.atapi.ccb[5]) | (request->u.atapi.ccb[4]<<8) |
 562                    (request->u.atapi.ccb[3]<<16)|(request->u.atapi.ccb[2]<<24);
 563         case ATAPI_READ:
 564         case ATAPI_WRITE:
 565             return (request->u.atapi.ccb[4]) | (request->u.atapi.ccb[3]<<8) |
 566                    (request->u.atapi.ccb[2]<<16);
 567         default:
 568             return 0;
 569         }
 570     }
 571     else
 572         return request->u.ata.lba;
 573 }
 574
 575 static void
 576 ata_sort_queue(struct ata_channel *ch, struct ata_request *request)
 577 {
 578     struct ata_request *this, *next;
 579
 580     this = TAILQ_FIRST(&ch->ata_queue);
 581
 582     /* if the queue is empty just insert */
 583     if (!this) {
 584         if (request->composite)
 585             ch->freezepoint = request;
 586         TAILQ_INSERT_TAIL(&ch->ata_queue, request, chain);
 587         return;
 588     }
 589
 590     /* dont sort frozen parts of the queue */
 591     if (ch->freezepoint)
 592         this = ch->freezepoint;
 593
 594     /* if position is less than head we add after tipping point */
 595     if (ata_get_lba(request) < ata_get_lba(this)) {
 596         while ((next = TAILQ_NEXT(this, chain))) {
 597
 598             /* have we reached the tipping point */
 599             if (ata_get_lba(next) < ata_get_lba(this)) {
 600
 601                 /* sort the insert */
 602                 do {
 603                     if (ata_get_lba(request) < ata_get_lba(next))
 604                         break;
 605                     this = next;
 606                 } while ((next = TAILQ_NEXT(this, chain)));
 607                 break;
 608             }
 609             this = next;
 610         }
 611     }
 612
 613     /* we are after head so sort the insert before tipping point */
 614     else {
 615         while ((next = TAILQ_NEXT(this, chain))) {
 616             if (ata_get_lba(next) < ata_get_lba(this) ||
 617                 ata_get_lba(request) < ata_get_lba(next))
 618                 break;
 619             this = next;
 620         }
 621     }
 622
 623     if (request->composite)
 624         ch->freezepoint = request;
 625     TAILQ_INSERT_AFTER(&ch->ata_queue, this, request, chain);
 626 }
 627
 628 char *
 629 ata_cmd2str(struct ata_request *request)
 630 {
 631     static char buffer[20];
 632
 633     if (request->flags & ATA_R_ATAPI) {
 634         switch (request->u.atapi.sense.key ?
 635                 request->u.atapi.saved_cmd : request->u.atapi.ccb[0]) {
 636         case 0x00: return ("TEST_UNIT_READY");
 637         case 0x01: return ("REZERO");
 638         case 0x03: return ("REQUEST_SENSE");
 639         case 0x04: return ("FORMAT");
 640         case 0x08: return ("READ");
 641         case 0x0a: return ("WRITE");
 642         case 0x10: return ("WEOF");
 643         case 0x11: return ("SPACE");
 644         case 0x12: return ("INQUIRY");
 645         case 0x15: return ("MODE_SELECT");
 646         case 0x19: return ("ERASE");
 647         case 0x1a: return ("MODE_SENSE");
 648         case 0x1b: return ("START_STOP");
 649         case 0x1e: return ("PREVENT_ALLOW");
 650         case 0x23: return ("ATAPI_READ_FORMAT_CAPACITIES");
 651         case 0x25: return ("READ_CAPACITY");
 652         case 0x28: return ("READ_BIG");
 653         case 0x2a: return ("WRITE_BIG");
 654         case 0x2b: return ("LOCATE");
 655         case 0x34: return ("READ_POSITION");
 656         case 0x35: return ("SYNCHRONIZE_CACHE");
 657         case 0x3b: return ("WRITE_BUFFER");
 658         case 0x3c: return ("READ_BUFFER");
 659         case 0x42: return ("READ_SUBCHANNEL");
 660         case 0x43: return ("READ_TOC");
 661         case 0x45: return ("PLAY_10");
 662         case 0x47: return ("PLAY_MSF");
 663         case 0x48: return ("PLAY_TRACK");
 664         case 0x4b: return ("PAUSE");
 665         case 0x51: return ("READ_DISK_INFO");
 666         case 0x52: return ("READ_TRACK_INFO");
 667         case 0x53: return ("RESERVE_TRACK");
 668         case 0x54: return ("SEND_OPC_INFO");
 669         case 0x55: return ("MODE_SELECT_BIG");
 670         case 0x58: return ("REPAIR_TRACK");
 671         case 0x59: return ("READ_MASTER_CUE");
 672         case 0x5a: return ("MODE_SENSE_BIG");
 673         case 0x5b: return ("CLOSE_TRACK/SESSION");
 674         case 0x5c: return ("READ_BUFFER_CAPACITY");
 675         case 0x5d: return ("SEND_CUE_SHEET");
 676         case 0x96: return ("SERVICE_ACTION_IN");
 677         case 0xa1: return ("BLANK_CMD");
 678         case 0xa3: return ("SEND_KEY");
 679         case 0xa4: return ("REPORT_KEY");
 680         case 0xa5: return ("PLAY_12");
 681         case 0xa6: return ("LOAD_UNLOAD");
 682         case 0xad: return ("READ_DVD_STRUCTURE");
 683         case 0xb4: return ("PLAY_CD");
 684         case 0xbb: return ("SET_SPEED");
 685         case 0xbd: return ("MECH_STATUS");
 686         case 0xbe: return ("READ_CD");
 687         case 0xff: return ("POLL_DSC");
 688         }
 689     }
 690     else {
 691         switch (request->u.ata.command) {
 692         case 0x00: return ("NOP");
 693         case 0x08: return ("DEVICE_RESET");
 694         case 0x20: return ("READ");
 695         case 0x24: return ("READ48");
 696         case 0x25: return ("READ_DMA48");
 697         case 0x26: return ("READ_DMA_QUEUED48");
 698         case 0x27: return ("READ_NATIVE_MAX_ADDRESS48");
 699         case 0x29: return ("READ_MUL48");
 700         case 0x30: return ("WRITE");
 701         case 0x34: return ("WRITE48");
 702         case 0x35: return ("WRITE_DMA48");
 703         case 0x36: return ("WRITE_DMA_QUEUED48");
 704         case 0x37: return ("SET_MAX_ADDRESS48");
 705         case 0x39: return ("WRITE_MUL48");
 706         case 0x70: return ("SEEK");
 707         case 0xa0: return ("PACKET_CMD");
 708         case 0xa1: return ("ATAPI_IDENTIFY");
 709         case 0xa2: return ("SERVICE");
 710         case 0xb0: return ("SMART");
 711         case 0xc0: return ("CFA ERASE");
 712         case 0xc4: return ("READ_MUL");
 713         case 0xc5: return ("WRITE_MUL");
 714         case 0xc6: return ("SET_MULTI");
 715         case 0xc7: return ("READ_DMA_QUEUED");
 716         case 0xc8: return ("READ_DMA");
 717         case 0xca: return ("WRITE_DMA");
 718         case 0xcc: return ("WRITE_DMA_QUEUED");
 719         case 0xe6: return ("SLEEP");
 720         case 0xe7: return ("FLUSHCACHE");
 721         case 0xea: return ("FLUSHCACHE48");
 722         case 0xec: return ("ATA_IDENTIFY");
 723         case 0xef:
 724             switch (request->u.ata.feature) {
 725             case 0x03: return ("SETFEATURES SET TRANSFER MODE");
 726             case 0x02: return ("SETFEATURES ENABLE WCACHE");
 727             case 0x82: return ("SETFEATURES DISABLE WCACHE");
 728             case 0xaa: return ("SETFEATURES ENABLE RCACHE");
 729             case 0x55: return ("SETFEATURES DISABLE RCACHE");
 730             }
 731             sprintf(buffer, "SETFEATURES 0x%02x", request->u.ata.feature);
 732             return buffer;
 733         case 0xf5: return ("SECURITY_FREE_LOCK");
 734         case 0xf8: return ("READ_NATIVE_MAX_ADDRESS");
 735         case 0xf9: return ("SET_MAX_ADDRESS");
 736         }
 737     }
 738     sprintf(buffer, "unknown CMD (0x%02x)", request->u.ata.command);
 739     return buffer;
 740 }
 741
 742 static char *
 743 ata_skey2str(u_int8_t skey)
 744 {
 745     switch (skey) {
 746     case 0x00: return ("NO SENSE");
 747     case 0x01: return ("RECOVERED ERROR");
 748     case 0x02: return ("NOT READY");
 749     case 0x03: return ("MEDIUM ERROR");
 750     case 0x04: return ("HARDWARE ERROR");
 751     case 0x05: return ("ILLEGAL REQUEST");
 752     case 0x06: return ("UNIT ATTENTION");
 753     case 0x07: return ("DATA PROTECT");
 754     case 0x08: return ("BLANK CHECK");
 755     case 0x09: return ("VENDOR SPECIFIC");
 756     case 0x0a: return ("COPY ABORTED");
 757     case 0x0b: return ("ABORTED COMMAND");
 758     case 0x0c: return ("EQUAL");
 759     case 0x0d: return ("VOLUME OVERFLOW");
 760     case 0x0e: return ("MISCOMPARE");
 761     case 0x0f: return ("RESERVED");
 762     default: return("UNKNOWN");
 763     }
 764 }