sys/cam/scsi/scsi_sg.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   3  *
   4  * Copyright (c) 2007 Scott Long
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions, and the following disclaimer,
  12  *    without modification, immediately at the beginning of the file.
  13  * 2. The name of the author may not be used to endorse or promote products
  14  *    derived from this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  19  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
  20  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  26  * SUCH DAMAGE.
  27  */
  28
  29 /*
  30  * scsi_sg peripheral driver.  This driver is meant to implement the Linux
  31  * SG passthrough interface for SCSI.
  32  */
  33
  34 #include <sys/cdefs.h>
  35 __FBSDID("$FreeBSD$");
  36
  37 #include <sys/param.h>
  38 #include <sys/systm.h>
  39 #include <sys/kernel.h>
  40 #include <sys/types.h>
  41 #include <sys/bio.h>
  42 #include <sys/malloc.h>
  43 #include <sys/fcntl.h>
  44 #include <sys/ioccom.h>
  45 #include <sys/conf.h>
  46 #include <sys/errno.h>
  47 #include <sys/devicestat.h>
  48 #include <sys/proc.h>
  49 #include <sys/uio.h>
  50
  51 #include <cam/cam.h>
  52 #include <cam/cam_ccb.h>
  53 #include <cam/cam_periph.h>
  54 #include <cam/cam_queue.h>
  55 #include <cam/cam_xpt_periph.h>
  56 #include <cam/cam_debug.h>
  57 #include <cam/cam_sim.h>
  58
  59 #include <cam/scsi/scsi_all.h>
  60 #include <cam/scsi/scsi_message.h>
  61 #include <cam/scsi/scsi_sg.h>
  62
  63 typedef enum {
  64         SG_FLAG_LOCKED          = 0x01,
  65         SG_FLAG_INVALID         = 0x02
  66 } sg_flags;
  67
  68 typedef enum {
  69         SG_STATE_NORMAL
  70 } sg_state;
  71
  72 typedef enum {
  73         SG_RDWR_FREE,
  74         SG_RDWR_INPROG,
  75         SG_RDWR_DONE
  76 } sg_rdwr_state;
  77
  78 typedef enum {
  79         SG_CCB_RDWR_IO
  80 } sg_ccb_types;
  81
  82 #define ccb_type        ppriv_field0
  83 #define ccb_rdwr        ppriv_ptr1
  84
  85 struct sg_rdwr {
  86         TAILQ_ENTRY(sg_rdwr)    rdwr_link;
  87         int                     tag;
  88         int                     state;
  89         int                     buf_len;
  90         char                    *buf;
  91         union ccb               *ccb;
  92         union {
  93                 struct sg_header hdr;
  94                 struct sg_io_hdr io_hdr;
  95         } hdr;
  96 };
  97
  98 struct sg_softc {
  99         sg_state                state;
 100         sg_flags                flags;
 101         int                     open_count;
 102         u_int                   maxio;
 103         struct devstat          *device_stats;
 104         TAILQ_HEAD(, sg_rdwr)   rdwr_done;
 105         struct cdev             *dev;
 106         int                     sg_timeout;
 107         int                     sg_user_timeout;
 108         uint8_t                 pd_type;
 109 };
 110
 111 static d_open_t         sgopen;
 112 static d_close_t        sgclose;
 113 static d_ioctl_t        sgioctl;
 114 static d_write_t        sgwrite;
 115 static d_read_t         sgread;
 116
 117 static periph_init_t    sginit;
 118 static periph_ctor_t    sgregister;
 119 static periph_oninv_t   sgoninvalidate;
 120 static periph_dtor_t    sgcleanup;
 121 static void             sgasync(void *callback_arg, uint32_t code,
 122                                 struct cam_path *path, void *arg);
 123 static void             sgdone(struct cam_periph *periph, union ccb *done_ccb);
 124 static int              sgsendccb(struct cam_periph *periph, union ccb *ccb);
 125 static int              sgsendrdwr(struct cam_periph *periph, union ccb *ccb);
 126 static int              sgerror(union ccb *ccb, uint32_t cam_flags,
 127                                 uint32_t sense_flags);
 128 static void             sg_scsiio_status(struct ccb_scsiio *csio,
 129                                          u_short *hoststat, u_short *drvstat);
 130
 131 static int              scsi_group_len(u_char cmd);
 132
 133 static struct periph_driver sgdriver =
 134 {
 135         sginit, "sg",
 136         TAILQ_HEAD_INITIALIZER(sgdriver.units), /* gen */ 0
 137 };
 138 PERIPHDRIVER_DECLARE(sg, sgdriver);
 139
 140 static struct cdevsw sg_cdevsw = {
 141         .d_version =    D_VERSION,
 142         .d_flags =      D_TRACKCLOSE,
 143         .d_open =       sgopen,
 144         .d_close =      sgclose,
 145         .d_ioctl =      sgioctl,
 146         .d_write =      sgwrite,
 147         .d_read =       sgread,
 148         .d_name =       "sg",
 149 };
 150
 151 static int sg_version = 30125;
 152
 153 static void
 154 sginit(void)
 155 {
 156         cam_status status;
 157
 158         /*
 159          * Install a global async callback.  This callback will receive aync
 160          * callbacks like "new device found".
 161          */
 162         status = xpt_register_async(AC_FOUND_DEVICE, sgasync, NULL, NULL);
 163
 164         if (status != CAM_REQ_CMP) {
 165                 printf("sg: Failed to attach master async callbac "
 166                         "due to status 0x%x!\n", status);
 167         }
 168 }
 169
 170 static void
 171 sgdevgonecb(void *arg)
 172 {
 173         struct cam_periph *periph;
 174         struct sg_softc *softc;
 175         struct mtx *mtx;
 176         int i;
 177
 178         periph = (struct cam_periph *)arg;
 179         mtx = cam_periph_mtx(periph);
 180         mtx_lock(mtx);
 181
 182         softc = (struct sg_softc *)periph->softc;
 183         KASSERT(softc->open_count >= 0, ("Negative open count %d",
 184                 softc->open_count));
 185
 186         /*
 187          * When we get this callback, we will get no more close calls from
 188          * devfs.  So if we have any dangling opens, we need to release the
 189          * reference held for that particular context.
 190          */
 191         for (i = 0; i < softc->open_count; i++)
 192                 cam_periph_release_locked(periph);
 193
 194         softc->open_count = 0;
 195
 196         /*
 197          * Release the reference held for the device node, it is gone now.
 198          */
 199         cam_periph_release_locked(periph);
 200
 201         /*
 202          * We reference the lock directly here, instead of using
 203          * cam_periph_unlock().  The reason is that the final call to
 204          * cam_periph_release_locked() above could result in the periph
 205          * getting freed.  If that is the case, dereferencing the periph
 206          * with a cam_periph_unlock() call would cause a page fault.
 207          */
 208         mtx_unlock(mtx);
 209 }
 210
 211 static void
 212 sgoninvalidate(struct cam_periph *periph)
 213 {
 214         struct sg_softc *softc;
 215
 216         softc = (struct sg_softc *)periph->softc;
 217
 218         /*
 219          * Deregister any async callbacks.
 220          */
 221         xpt_register_async(0, sgasync, periph, periph->path);
 222
 223         softc->flags |= SG_FLAG_INVALID;
 224
 225         /*
 226          * Tell devfs this device has gone away, and ask for a callback
 227          * when it has cleaned up its state.
 228          */
 229         destroy_dev_sched_cb(softc->dev, sgdevgonecb, periph);
 230
 231         /*
 232          * XXX Return all queued I/O with ENXIO.
 233          * XXX Handle any transactions queued to the card
 234          *     with XPT_ABORT_CCB.
 235          */
 236
 237 }
 238
 239 static void
 240 sgcleanup(struct cam_periph *periph)
 241 {
 242         struct sg_softc *softc;
 243
 244         softc = (struct sg_softc *)periph->softc;
 245
 246         devstat_remove_entry(softc->device_stats);
 247
 248         free(softc, M_DEVBUF);
 249 }
 250
 251 static void
 252 sgasync(void *callback_arg, uint32_t code, struct cam_path *path, void *arg)
 253 {
 254         struct cam_periph *periph;
 255
 256         periph = (struct cam_periph *)callback_arg;
 257
 258         switch (code) {
 259         case AC_FOUND_DEVICE:
 260         {
 261                 struct ccb_getdev *cgd;
 262                 cam_status status;
 263
 264                 cgd = (struct ccb_getdev *)arg;
 265                 if (cgd == NULL)
 266                         break;
 267
 268                 if (cgd->protocol != PROTO_SCSI)
 269                         break;
 270
 271                 /*
 272                  * Allocate a peripheral instance for this device and
 273                  * start the probe process.
 274                  */
 275                 status = cam_periph_alloc(sgregister, sgoninvalidate,
 276                                           sgcleanup, NULL, "sg",
 277                                           CAM_PERIPH_BIO, path,
 278                                           sgasync, AC_FOUND_DEVICE, cgd);
 279                 if ((status != CAM_REQ_CMP) && (status != CAM_REQ_INPROG)) {
 280                         const struct cam_status_entry *entry;
 281
 282                         entry = cam_fetch_status_entry(status);
 283                         printf("sgasync: Unable to attach new device "
 284                                 "due to status %#x: %s\n", status, entry ?
 285                                 entry->status_text : "Unknown");
 286                 }
 287                 break;
 288         }
 289         default:
 290                 cam_periph_async(periph, code, path, arg);
 291                 break;
 292         }
 293 }
 294
 295 static cam_status
 296 sgregister(struct cam_periph *periph, void *arg)
 297 {
 298         struct sg_softc *softc;
 299         struct ccb_getdev *cgd;
 300         struct ccb_pathinq cpi;
 301         struct make_dev_args args;
 302         int no_tags, error;
 303
 304         cgd = (struct ccb_getdev *)arg;
 305         if (cgd == NULL) {
 306                 printf("sgregister: no getdev CCB, can't register device\n");
 307                 return (CAM_REQ_CMP_ERR);
 308         }
 309
 310         softc = malloc(sizeof(*softc), M_DEVBUF, M_ZERO | M_NOWAIT);
 311         if (softc == NULL) {
 312                 printf("sgregister: Unable to allocate softc\n");
 313                 return (CAM_REQ_CMP_ERR);
 314         }
 315
 316         softc->state = SG_STATE_NORMAL;
 317         softc->pd_type = SID_TYPE(&cgd->inq_data);
 318         softc->sg_timeout = SG_DEFAULT_TIMEOUT / SG_DEFAULT_HZ * hz;
 319         softc->sg_user_timeout = SG_DEFAULT_TIMEOUT;
 320         TAILQ_INIT(&softc->rdwr_done);
 321         periph->softc = softc;
 322
 323         xpt_path_inq(&cpi, periph->path);
 324
 325         if (cpi.maxio == 0)
 326                 softc->maxio = DFLTPHYS;        /* traditional default */
 327         else if (cpi.maxio > maxphys)
 328                 softc->maxio = maxphys;         /* for safety */
 329         else
 330                 softc->maxio = cpi.maxio;       /* real value */
 331
 332         /*
 333          * We pass in 0 for all blocksize, since we don't know what the
 334          * blocksize of the device is, if it even has a blocksize.
 335          */
 336         cam_periph_unlock(periph);
 337         no_tags = (cgd->inq_data.flags & SID_CmdQue) == 0;
 338         softc->device_stats = devstat_new_entry("sg",
 339                         periph->unit_number, 0,
 340                         DEVSTAT_NO_BLOCKSIZE
 341                         | (no_tags ? DEVSTAT_NO_ORDERED_TAGS : 0),
 342                         softc->pd_type |
 343                         XPORT_DEVSTAT_TYPE(cpi.transport) |
 344                         DEVSTAT_TYPE_PASS,
 345                         DEVSTAT_PRIORITY_PASS);
 346
 347         /*
 348          * Acquire a reference to the periph before we create the devfs
 349          * instance for it.  We'll release this reference once the devfs
 350          * instance has been freed.
 351          */
 352         if (cam_periph_acquire(periph) != 0) {
 353                 xpt_print(periph->path, "%s: lost periph during "
 354                           "registration!\n", __func__);
 355                 cam_periph_lock(periph);
 356                 return (CAM_REQ_CMP_ERR);
 357         }
 358
 359         /* Register the device */
 360         make_dev_args_init(&args);
 361         args.mda_devsw = &sg_cdevsw;
 362         args.mda_unit = periph->unit_number;
 363         args.mda_uid = UID_ROOT;
 364         args.mda_gid = GID_OPERATOR;
 365         args.mda_mode = 0600;
 366         args.mda_si_drv1 = periph;
 367         error = make_dev_s(&args, &softc->dev, "%s%d",
 368             periph->periph_name, periph->unit_number);
 369         if (error != 0) {
 370                 cam_periph_lock(periph);
 371                 cam_periph_release_locked(periph);
 372                 return (CAM_REQ_CMP_ERR);
 373         }
 374         if (periph->unit_number < 26) {
 375                 (void)make_dev_alias(softc->dev, "sg%c",
 376                     periph->unit_number + 'a');
 377         } else {
 378                 (void)make_dev_alias(softc->dev, "sg%c%c",
 379                     ((periph->unit_number / 26) - 1) + 'a',
 380                     (periph->unit_number % 26) + 'a');
 381         }
 382         cam_periph_lock(periph);
 383
 384         /*
 385          * Add as async callback so that we get
 386          * notified if this device goes away.
 387          */
 388         xpt_register_async(AC_LOST_DEVICE, sgasync, periph, periph->path);
 389
 390         if (bootverbose)
 391                 xpt_announce_periph(periph, NULL);
 392
 393         return (CAM_REQ_CMP);
 394 }
 395
 396 static void
 397 sgdone(struct cam_periph *periph, union ccb *done_ccb)
 398 {
 399         struct sg_softc *softc;
 400         struct ccb_scsiio *csio;
 401
 402         softc = (struct sg_softc *)periph->softc;
 403         csio = &done_ccb->csio;
 404         switch (csio->ccb_h.ccb_type) {
 405         case SG_CCB_RDWR_IO:
 406         {
 407                 struct sg_rdwr *rdwr;
 408                 int state;
 409
 410                 devstat_end_transaction(softc->device_stats,
 411                                         csio->dxfer_len,
 412                                         csio->tag_action & 0xf,
 413                                         ((csio->ccb_h.flags & CAM_DIR_MASK) ==
 414                                         CAM_DIR_NONE) ? DEVSTAT_NO_DATA :
 415                                         (csio->ccb_h.flags & CAM_DIR_OUT) ?
 416                                         DEVSTAT_WRITE : DEVSTAT_READ,
 417                                         NULL, NULL);
 418
 419                 rdwr = done_ccb->ccb_h.ccb_rdwr;
 420                 state = rdwr->state;
 421                 rdwr->state = SG_RDWR_DONE;
 422                 wakeup(rdwr);
 423                 break;
 424         }
 425         default:
 426                 panic("unknown sg CCB type");
 427         }
 428 }
 429
 430 static int
 431 sgopen(struct cdev *dev, int flags, int fmt, struct thread *td)
 432 {
 433         struct cam_periph *periph;
 434         struct sg_softc *softc;
 435         int error = 0;
 436
 437         periph = (struct cam_periph *)dev->si_drv1;
 438         if (cam_periph_acquire(periph) != 0)
 439                 return (ENXIO);
 440
 441         /*
 442          * Don't allow access when we're running at a high securelevel.
 443          */
 444         error = securelevel_gt(td->td_ucred, 1);
 445         if (error) {
 446                 cam_periph_release(periph);
 447                 return (error);
 448         }
 449
 450         cam_periph_lock(periph);
 451
 452         softc = (struct sg_softc *)periph->softc;
 453         if (softc->flags & SG_FLAG_INVALID) {
 454                 cam_periph_release_locked(periph);
 455                 cam_periph_unlock(periph);
 456                 return (ENXIO);
 457         }
 458
 459         softc->open_count++;
 460
 461         cam_periph_unlock(periph);
 462
 463         return (error);
 464 }
 465
 466 static int
 467 sgclose(struct cdev *dev, int flag, int fmt, struct thread *td)
 468 {
 469         struct cam_periph *periph;
 470         struct sg_softc   *softc;
 471         struct mtx *mtx;
 472
 473         periph = (struct cam_periph *)dev->si_drv1;
 474         mtx = cam_periph_mtx(periph);
 475         mtx_lock(mtx);
 476
 477         softc = periph->softc;
 478         softc->open_count--;
 479
 480         cam_periph_release_locked(periph);
 481
 482         /*
 483          * We reference the lock directly here, instead of using
 484          * cam_periph_unlock().  The reason is that the call to
 485          * cam_periph_release_locked() above could result in the periph
 486          * getting freed.  If that is the case, dereferencing the periph
 487          * with a cam_periph_unlock() call would cause a page fault.
 488          *
 489          * cam_periph_release() avoids this problem using the same method,
 490          * but we're manually acquiring and dropping the lock here to
 491          * protect the open count and avoid another lock acquisition and
 492          * release.
 493          */
 494         mtx_unlock(mtx);
 495
 496         return (0);
 497 }
 498
 499 static int
 500 sgioctl(struct cdev *dev, u_long cmd, caddr_t arg, int flag, struct thread *td)
 501 {
 502         union ccb *ccb;
 503         struct ccb_scsiio *csio;
 504         struct cam_periph *periph;
 505         struct sg_softc *softc;
 506         struct sg_io_hdr *req;
 507         int dir, error;
 508
 509         periph = (struct cam_periph *)dev->si_drv1;
 510         cam_periph_lock(periph);
 511
 512         softc = (struct sg_softc *)periph->softc;
 513         error = 0;
 514
 515         switch (cmd) {
 516         case SG_GET_VERSION_NUM:
 517         {
 518                 int *version = (int *)arg;
 519
 520                 *version = sg_version;
 521                 break;
 522         }
 523         case SG_SET_TIMEOUT:
 524         {
 525                 u_int user_timeout = *(u_int *)arg;
 526
 527                 softc->sg_user_timeout = user_timeout;
 528                 softc->sg_timeout = user_timeout / SG_DEFAULT_HZ * hz;
 529                 break;
 530         }
 531         case SG_GET_TIMEOUT:
 532                 /*
 533                  * The value is returned directly to the syscall.
 534                  */
 535                 td->td_retval[0] = softc->sg_user_timeout;
 536                 error = 0;
 537                 break;
 538         case SG_IO:
 539                 req = (struct sg_io_hdr *)arg;
 540
 541                 if (req->cmd_len > IOCDBLEN) {
 542                         error = EINVAL;
 543                         break;
 544                 }
 545
 546                 if (req->iovec_count != 0) {
 547                         error = EOPNOTSUPP;
 548                         break;
 549                 }
 550
 551                 ccb = cam_periph_getccb(periph, CAM_PRIORITY_NORMAL);
 552                 csio = &ccb->csio;
 553
 554                 error = copyin(req->cmdp, &csio->cdb_io.cdb_bytes,
 555                     req->cmd_len);
 556                 if (error) {
 557                         xpt_release_ccb(ccb);
 558                         break;
 559                 }
 560
 561                 switch(req->dxfer_direction) {
 562                 case SG_DXFER_TO_DEV:
 563                         dir = CAM_DIR_OUT;
 564                         break;
 565                 case SG_DXFER_FROM_DEV:
 566                         dir = CAM_DIR_IN;
 567                         break;
 568                 case SG_DXFER_TO_FROM_DEV:
 569                         dir = CAM_DIR_BOTH;
 570                         break;
 571                 case SG_DXFER_NONE:
 572                 default:
 573                         dir = CAM_DIR_NONE;
 574                         break;
 575                 }
 576
 577                 cam_fill_csio(csio,
 578                               /*retries*/1,
 579                               /*cbfcnp*/NULL,
 580                               dir|CAM_DEV_QFRZDIS,
 581                               MSG_SIMPLE_Q_TAG,
 582                               req->dxferp,
 583                               req->dxfer_len,
 584                               req->mx_sb_len,
 585                               req->cmd_len,
 586                               req->timeout);
 587
 588                 error = sgsendccb(periph, ccb);
 589                 if (error) {
 590                         req->host_status = DID_ERROR;
 591                         req->driver_status = DRIVER_INVALID;
 592                         xpt_release_ccb(ccb);
 593                         break;
 594                 }
 595
 596                 req->status = csio->scsi_status;
 597                 req->masked_status = (csio->scsi_status >> 1) & 0x7f;
 598                 sg_scsiio_status(csio, &req->host_status, &req->driver_status);
 599                 req->resid = csio->resid;
 600                 req->duration = csio->ccb_h.timeout;
 601                 req->info = 0;
 602
 603                 if ((csio->ccb_h.status & CAM_AUTOSNS_VALID)
 604                     && (req->sbp != NULL)) {
 605                         req->sb_len_wr = req->mx_sb_len - csio->sense_resid;
 606                         error = copyout(&csio->sense_data, req->sbp,
 607                                         req->sb_len_wr);
 608                 }
 609
 610                 xpt_release_ccb(ccb);
 611                 break;
 612
 613         case SG_GET_RESERVED_SIZE:
 614         {
 615                 int *size = (int *)arg;
 616                 *size = DFLTPHYS;
 617                 break;
 618         }
 619
 620         case SG_GET_SCSI_ID:
 621         {
 622                 struct sg_scsi_id *id = (struct sg_scsi_id *)arg;
 623
 624                 id->host_no = cam_sim_path(xpt_path_sim(periph->path));
 625                 id->channel = xpt_path_path_id(periph->path);
 626                 id->scsi_id = xpt_path_target_id(periph->path);
 627                 id->lun = xpt_path_lun_id(periph->path);
 628                 id->scsi_type = softc->pd_type;
 629                 id->h_cmd_per_lun = 1;
 630                 id->d_queue_depth = 1;
 631                 id->unused[0] = 0;
 632                 id->unused[1] = 0;
 633                 break;
 634         }
 635
 636         case SG_GET_SG_TABLESIZE:
 637         {
 638                 int *size = (int *)arg;
 639                 *size = 0;
 640                 break;
 641         }
 642
 643         case SG_EMULATED_HOST:
 644         case SG_SET_TRANSFORM:
 645         case SG_GET_TRANSFORM:
 646         case SG_GET_NUM_WAITING:
 647         case SG_SCSI_RESET:
 648         case SG_GET_REQUEST_TABLE:
 649         case SG_SET_KEEP_ORPHAN:
 650         case SG_GET_KEEP_ORPHAN:
 651         case SG_GET_ACCESS_COUNT:
 652         case SG_SET_FORCE_LOW_DMA:
 653         case SG_GET_LOW_DMA:
 654         case SG_SET_FORCE_PACK_ID:
 655         case SG_GET_PACK_ID:
 656         case SG_SET_RESERVED_SIZE:
 657         case SG_GET_COMMAND_Q:
 658         case SG_SET_COMMAND_Q:
 659         case SG_SET_DEBUG:
 660         case SG_NEXT_CMD_LEN:
 661         default:
 662 #ifdef CAMDEBUG
 663                 printf("sgioctl: rejecting cmd 0x%lx\n", cmd);
 664 #endif
 665                 error = ENODEV;
 666                 break;
 667         }
 668
 669         cam_periph_unlock(periph);
 670         return (error);
 671 }
 672
 673 static int
 674 sgwrite(struct cdev *dev, struct uio *uio, int ioflag)
 675 {
 676         union ccb *ccb;
 677         struct cam_periph *periph;
 678         struct ccb_scsiio *csio;
 679         struct sg_softc *sc;
 680         struct sg_header *hdr;
 681         struct sg_rdwr *rdwr;
 682         u_char cdb_cmd;
 683         char *buf;
 684         int error = 0, cdb_len, buf_len, dir;
 685
 686         periph = dev->si_drv1;
 687         rdwr = malloc(sizeof(*rdwr), M_DEVBUF, M_WAITOK | M_ZERO);
 688         hdr = &rdwr->hdr.hdr;
 689
 690         /* Copy in the header block and sanity check it */
 691         if (uio->uio_resid < sizeof(*hdr)) {
 692                 error = EINVAL;
 693                 goto out_hdr;
 694         }
 695         error = uiomove(hdr, sizeof(*hdr), uio);
 696         if (error)
 697                 goto out_hdr;
 698
 699         /* XXX: We don't support SG 3.x read/write API. */
 700         if (hdr->reply_len < 0) {
 701                 error = ENODEV;
 702                 goto out_hdr;
 703         }
 704
 705         ccb = xpt_alloc_ccb();
 706         if (ccb == NULL) {
 707                 error = ENOMEM;
 708                 goto out_hdr;
 709         }
 710         csio = &ccb->csio;
 711
 712         /*
 713          * Copy in the CDB block.  The designers of the interface didn't
 714          * bother to provide a size for this in the header, so we have to
 715          * figure it out ourselves.
 716          */
 717         if (uio->uio_resid < 1)
 718                 goto out_ccb;
 719         error = uiomove(&cdb_cmd, 1, uio);
 720         if (error)
 721                 goto out_ccb;
 722         if (hdr->twelve_byte)
 723                 cdb_len = 12;
 724         else
 725                 cdb_len = scsi_group_len(cdb_cmd);
 726         /*
 727          * We've already read the first byte of the CDB and advanced the uio
 728          * pointer.  Just read the rest.
 729          */
 730         csio->cdb_io.cdb_bytes[0] = cdb_cmd;
 731         error = uiomove(&csio->cdb_io.cdb_bytes[1], cdb_len - 1, uio);
 732         if (error)
 733                 goto out_ccb;
 734
 735         /*
 736          * Now set up the data block.  Again, the designers didn't bother
 737          * to make this reliable.
 738          */
 739         buf_len = uio->uio_resid;
 740         if (buf_len != 0) {
 741                 buf = malloc(buf_len, M_DEVBUF, M_WAITOK | M_ZERO);
 742                 error = uiomove(buf, buf_len, uio);
 743                 if (error)
 744                         goto out_buf;
 745                 dir = CAM_DIR_OUT;
 746         } else if (hdr->reply_len != 0) {
 747                 buf = malloc(hdr->reply_len, M_DEVBUF, M_WAITOK | M_ZERO);
 748                 buf_len = hdr->reply_len;
 749                 dir = CAM_DIR_IN;
 750         } else {
 751                 buf = NULL;
 752                 buf_len = 0;
 753                 dir = CAM_DIR_NONE;
 754         }
 755
 756         cam_periph_lock(periph);
 757         sc = periph->softc;
 758         xpt_setup_ccb(&ccb->ccb_h, periph->path, CAM_PRIORITY_NORMAL);
 759         cam_fill_csio(csio,
 760                       /*retries*/1,
 761                       sgdone,
 762                       dir|CAM_DEV_QFRZDIS,
 763                       MSG_SIMPLE_Q_TAG,
 764                       buf,
 765                       buf_len,
 766                       SG_MAX_SENSE,
 767                       cdb_len,
 768                       sc->sg_timeout);
 769
 770         /*
 771          * Send off the command and hope that it works. This path does not
 772          * go through sgstart because the I/O is supposed to be asynchronous.
 773          */
 774         rdwr->buf = buf;
 775         rdwr->buf_len = buf_len;
 776         rdwr->tag = hdr->pack_id;
 777         rdwr->ccb = ccb;
 778         rdwr->state = SG_RDWR_INPROG;
 779         ccb->ccb_h.ccb_rdwr = rdwr;
 780         ccb->ccb_h.ccb_type = SG_CCB_RDWR_IO;
 781         TAILQ_INSERT_TAIL(&sc->rdwr_done, rdwr, rdwr_link);
 782         error = sgsendrdwr(periph, ccb);
 783         cam_periph_unlock(periph);
 784         return (error);
 785
 786 out_buf:
 787         free(buf, M_DEVBUF);
 788 out_ccb:
 789         xpt_free_ccb(ccb);
 790 out_hdr:
 791         free(rdwr, M_DEVBUF);
 792         return (error);
 793 }
 794
 795 static int
 796 sgread(struct cdev *dev, struct uio *uio, int ioflag)
 797 {
 798         struct ccb_scsiio *csio;
 799         struct cam_periph *periph;
 800         struct sg_softc *sc;
 801         struct sg_header *hdr;
 802         struct sg_rdwr *rdwr;
 803         u_short hstat, dstat;
 804         int error, pack_len, reply_len, pack_id;
 805
 806         periph = dev->si_drv1;
 807
 808         /* XXX The pack len field needs to be updated and written out instead
 809          * of discarded.  Not sure how to do that.
 810          */
 811         uio->uio_rw = UIO_WRITE;
 812         if ((error = uiomove(&pack_len, 4, uio)) != 0)
 813                 return (error);
 814         if ((error = uiomove(&reply_len, 4, uio)) != 0)
 815                 return (error);
 816         if ((error = uiomove(&pack_id, 4, uio)) != 0)
 817                 return (error);
 818         uio->uio_rw = UIO_READ;
 819
 820         cam_periph_lock(periph);
 821         sc = periph->softc;
 822 search:
 823         TAILQ_FOREACH(rdwr, &sc->rdwr_done, rdwr_link) {
 824                 if (rdwr->tag == pack_id)
 825                         break;
 826         }
 827         if ((rdwr == NULL) || (rdwr->state != SG_RDWR_DONE)) {
 828                 if (cam_periph_sleep(periph, rdwr, PCATCH, "sgread", 0) == ERESTART)
 829                         return (EAGAIN);
 830                 goto search;
 831         }
 832         TAILQ_REMOVE(&sc->rdwr_done, rdwr, rdwr_link);
 833         cam_periph_unlock(periph);
 834
 835         hdr = &rdwr->hdr.hdr;
 836         csio = &rdwr->ccb->csio;
 837         sg_scsiio_status(csio, &hstat, &dstat);
 838         hdr->host_status = hstat;
 839         hdr->driver_status = dstat;
 840         hdr->target_status = csio->scsi_status >> 1;
 841
 842         switch (hstat) {
 843         case DID_OK:
 844         case DID_PASSTHROUGH:
 845         case DID_SOFT_ERROR:
 846                 hdr->result = 0;
 847                 break;
 848         case DID_NO_CONNECT:
 849         case DID_BUS_BUSY:
 850         case DID_TIME_OUT:
 851                 hdr->result = EBUSY;
 852                 break;
 853         case DID_BAD_TARGET:
 854         case DID_ABORT:
 855         case DID_PARITY:
 856         case DID_RESET:
 857         case DID_BAD_INTR:
 858         case DID_ERROR:
 859         default:
 860                 hdr->result = EIO;
 861                 break;
 862         }
 863
 864         if (dstat == DRIVER_SENSE) {
 865                 bcopy(&csio->sense_data, hdr->sense_buffer,
 866                       min(csio->sense_len, SG_MAX_SENSE));
 867 #ifdef CAMDEBUG
 868                 scsi_sense_print(csio);
 869 #endif
 870         }
 871
 872         error = uiomove(&hdr->result, sizeof(*hdr) -
 873                         offsetof(struct sg_header, result), uio);
 874         if ((error == 0) && (hdr->result == 0))
 875                 error = uiomove(rdwr->buf, rdwr->buf_len, uio);
 876
 877         cam_periph_lock(periph);
 878         xpt_free_ccb(rdwr->ccb);
 879         cam_periph_unlock(periph);
 880         free(rdwr->buf, M_DEVBUF);
 881         free(rdwr, M_DEVBUF);
 882         return (error);
 883 }
 884
 885 static int
 886 sgsendccb(struct cam_periph *periph, union ccb *ccb)
 887 {
 888         struct sg_softc *softc;
 889         struct cam_periph_map_info mapinfo;
 890         int error;
 891
 892         softc = periph->softc;
 893         bzero(&mapinfo, sizeof(mapinfo));
 894
 895         /*
 896          * cam_periph_mapmem calls into proc and vm functions that can
 897          * sleep as well as trigger I/O, so we can't hold the lock.
 898          * Dropping it here is reasonably safe.
 899          * The only CCB opcode that is possible here is XPT_SCSI_IO, no
 900          * need for additional checks.
 901          */
 902         cam_periph_unlock(periph);
 903         error = cam_periph_mapmem(ccb, &mapinfo, softc->maxio);
 904         cam_periph_lock(periph);
 905         if (error)
 906                 return (error);
 907
 908         error = cam_periph_runccb(ccb,
 909                                   sgerror,
 910                                   CAM_RETRY_SELTO,
 911                                   SF_RETRY_UA,
 912                                   softc->device_stats);
 913
 914         cam_periph_unlock(periph);
 915         cam_periph_unmapmem(ccb, &mapinfo);
 916         cam_periph_lock(periph);
 917
 918         return (error);
 919 }
 920
 921 static int
 922 sgsendrdwr(struct cam_periph *periph, union ccb *ccb)
 923 {
 924         struct sg_softc *softc;
 925
 926         softc = periph->softc;
 927         devstat_start_transaction(softc->device_stats, NULL);
 928         xpt_action(ccb);
 929         return (0);
 930 }
 931
 932 static int
 933 sgerror(union ccb *ccb, uint32_t cam_flags, uint32_t sense_flags)
 934 {
 935         struct cam_periph *periph;
 936         struct sg_softc *softc;
 937
 938         periph = xpt_path_periph(ccb->ccb_h.path);
 939         softc = (struct sg_softc *)periph->softc;
 940
 941         return (cam_periph_error(ccb, cam_flags, sense_flags));
 942 }
 943
 944 static void
 945 sg_scsiio_status(struct ccb_scsiio *csio, u_short *hoststat, u_short *drvstat)
 946 {
 947         int status;
 948
 949         status = csio->ccb_h.status;
 950
 951         switch (status & CAM_STATUS_MASK) {
 952         case CAM_REQ_CMP:
 953                 *hoststat = DID_OK;
 954                 *drvstat = 0;
 955                 break;
 956         case CAM_REQ_CMP_ERR:
 957                 *hoststat = DID_ERROR;
 958                 *drvstat = 0;
 959                 break;
 960         case CAM_REQ_ABORTED:
 961                 *hoststat = DID_ABORT;
 962                 *drvstat = 0;
 963                 break;
 964         case CAM_REQ_INVALID:
 965                 *hoststat = DID_ERROR;
 966                 *drvstat = DRIVER_INVALID;
 967                 break;
 968         case CAM_DEV_NOT_THERE:
 969                 *hoststat = DID_BAD_TARGET;
 970                 *drvstat = 0;
 971                 break;
 972         case CAM_SEL_TIMEOUT:
 973                 *hoststat = DID_NO_CONNECT;
 974                 *drvstat = 0;
 975                 break;
 976         case CAM_CMD_TIMEOUT:
 977                 *hoststat = DID_TIME_OUT;
 978                 *drvstat = 0;
 979                 break;
 980         case CAM_SCSI_STATUS_ERROR:
 981                 *hoststat = DID_ERROR;
 982                 *drvstat = 0;
 983                 break;
 984         case CAM_SCSI_BUS_RESET:
 985                 *hoststat = DID_RESET;
 986                 *drvstat = 0;
 987                 break;
 988         case CAM_UNCOR_PARITY:
 989                 *hoststat = DID_PARITY;
 990                 *drvstat = 0;
 991                 break;
 992         case CAM_SCSI_BUSY:
 993                 *hoststat = DID_BUS_BUSY;
 994                 *drvstat = 0;
 995                 break;
 996         default:
 997                 *hoststat = DID_ERROR;
 998                 *drvstat = DRIVER_ERROR;
 999         }
1000
1001         if (status & CAM_AUTOSNS_VALID)
1002                 *drvstat = DRIVER_SENSE;
1003 }
1004
1005 static int
1006 scsi_group_len(u_char cmd)
1007 {
1008         int len[] = {6, 10, 10, 12, 12, 12, 10, 10};
1009         int group;
1010
1011         group = (cmd >> 5) & 0x7;
1012         return (len[group]);
1013 }