sys/cam/ctl/ctl_backend_ramdisk.c

   1 /*-
   2  * Copyright (c) 2003, 2008 Silicon Graphics International Corp.
   3  * Copyright (c) 2012 The FreeBSD Foundation
   4  * All rights reserved.
   5  *
   6  * Portions of this software were developed by Edward Tomasz Napierala
   7  * under sponsorship from the FreeBSD Foundation.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions, and the following disclaimer,
  14  *    without modification.
  15  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  16  *    substantially similar to the "NO WARRANTY" disclaimer below
  17  *    ("Disclaimer") and any redistribution must be conditioned upon
  18  *    including a substantially similar Disclaimer requirement for further
  19  *    binary redistribution.
  20  *
  21  * NO WARRANTY
  22  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  23  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  24  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  25  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  26  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  30  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  31  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  32  * POSSIBILITY OF SUCH DAMAGES.
  33  *
  34  * $Id: //depot/users/kenm/FreeBSD-test2/sys/cam/ctl/ctl_backend_ramdisk.c#3 $
  35  */
  36 /*
  37  * CAM Target Layer backend for a "fake" ramdisk.
  38  *
  39  * Author: Ken Merry <ken@FreeBSD.org>
  40  */
  41
  42 #include <sys/cdefs.h>
  43 __FBSDID("$FreeBSD$");
  44
  45 #include <sys/param.h>
  46 #include <sys/systm.h>
  47 #include <sys/kernel.h>
  48 #include <sys/condvar.h>
  49 #include <sys/types.h>
  50 #include <sys/lock.h>
  51 #include <sys/mutex.h>
  52 #include <sys/malloc.h>
  53 #include <sys/taskqueue.h>
  54 #include <sys/time.h>
  55 #include <sys/queue.h>
  56 #include <sys/conf.h>
  57 #include <sys/ioccom.h>
  58 #include <sys/module.h>
  59
  60 #include <cam/scsi/scsi_all.h>
  61 #include <cam/ctl/ctl_io.h>
  62 #include <cam/ctl/ctl.h>
  63 #include <cam/ctl/ctl_util.h>
  64 #include <cam/ctl/ctl_backend.h>
  65 #include <cam/ctl/ctl_frontend_internal.h>
  66 #include <cam/ctl/ctl_debug.h>
  67 #include <cam/ctl/ctl_ioctl.h>
  68 #include <cam/ctl/ctl_error.h>
  69
  70 typedef enum {
  71         CTL_BE_RAMDISK_LUN_UNCONFIGURED = 0x01,
  72         CTL_BE_RAMDISK_LUN_CONFIG_ERR   = 0x02,
  73         CTL_BE_RAMDISK_LUN_WAITING      = 0x04
  74 } ctl_be_ramdisk_lun_flags;
  75
  76 struct ctl_be_ramdisk_lun {
  77         char lunname[32];
  78         uint64_t size_bytes;
  79         uint64_t size_blocks;
  80         struct ctl_be_ramdisk_softc *softc;
  81         ctl_be_ramdisk_lun_flags flags;
  82         STAILQ_ENTRY(ctl_be_ramdisk_lun) links;
  83         struct ctl_be_lun ctl_be_lun;
  84         struct taskqueue *io_taskqueue;
  85         struct task io_task;
  86         STAILQ_HEAD(, ctl_io_hdr) cont_queue;
  87         struct mtx lock;
  88 };
  89
  90 struct ctl_be_ramdisk_softc {
  91         struct mtx lock;
  92         int rd_size;
  93 #ifdef CTL_RAMDISK_PAGES
  94         uint8_t **ramdisk_pages;
  95         int num_pages;
  96 #else
  97         uint8_t *ramdisk_buffer;
  98 #endif
  99         int num_luns;
 100         STAILQ_HEAD(, ctl_be_ramdisk_lun) lun_list;
 101 };
 102
 103 static struct ctl_be_ramdisk_softc rd_softc;
 104
 105 int ctl_backend_ramdisk_init(void);
 106 void ctl_backend_ramdisk_shutdown(void);
 107 static int ctl_backend_ramdisk_move_done(union ctl_io *io);
 108 static int ctl_backend_ramdisk_submit(union ctl_io *io);
 109 static void ctl_backend_ramdisk_continue(union ctl_io *io);
 110 static int ctl_backend_ramdisk_ioctl(struct cdev *dev, u_long cmd,
 111                                      caddr_t addr, int flag, struct thread *td);
 112 static int ctl_backend_ramdisk_rm(struct ctl_be_ramdisk_softc *softc,
 113                                   struct ctl_lun_req *req);
 114 static int ctl_backend_ramdisk_create(struct ctl_be_ramdisk_softc *softc,
 115                                       struct ctl_lun_req *req, int do_wait);
 116 static int ctl_backend_ramdisk_modify(struct ctl_be_ramdisk_softc *softc,
 117                                   struct ctl_lun_req *req);
 118 static void ctl_backend_ramdisk_worker(void *context, int pending);
 119 static void ctl_backend_ramdisk_lun_shutdown(void *be_lun);
 120 static void ctl_backend_ramdisk_lun_config_status(void *be_lun,
 121                                                   ctl_lun_config_status status);
 122 static int ctl_backend_ramdisk_config_write(union ctl_io *io);
 123 static int ctl_backend_ramdisk_config_read(union ctl_io *io);
 124
 125 static struct ctl_backend_driver ctl_be_ramdisk_driver =
 126 {
 127         .name = "ramdisk",
 128         .flags = CTL_BE_FLAG_HAS_CONFIG,
 129         .init = ctl_backend_ramdisk_init,
 130         .data_submit = ctl_backend_ramdisk_submit,
 131         .data_move_done = ctl_backend_ramdisk_move_done,
 132         .config_read = ctl_backend_ramdisk_config_read,
 133         .config_write = ctl_backend_ramdisk_config_write,
 134         .ioctl = ctl_backend_ramdisk_ioctl
 135 };
 136
 137 MALLOC_DEFINE(M_RAMDISK, "ramdisk", "Memory used for CTL RAMdisk");
 138 CTL_BACKEND_DECLARE(cbr, ctl_be_ramdisk_driver);
 139
 140 int
 141 ctl_backend_ramdisk_init(void)
 142 {
 143         struct ctl_be_ramdisk_softc *softc;
 144 #ifdef CTL_RAMDISK_PAGES
 145         int i;
 146 #endif
 147
 148
 149         softc = &rd_softc;
 150
 151         memset(softc, 0, sizeof(*softc));
 152
 153         mtx_init(&softc->lock, "ramdisk", NULL, MTX_DEF);
 154
 155         STAILQ_INIT(&softc->lun_list);
 156         softc->rd_size = 1024 * 1024;
 157 #ifdef CTL_RAMDISK_PAGES
 158         softc->num_pages = softc->rd_size / PAGE_SIZE;
 159         softc->ramdisk_pages = (uint8_t **)malloc(sizeof(uint8_t *) *
 160                                                   softc->num_pages, M_RAMDISK,
 161                                                   M_WAITOK);
 162         for (i = 0; i < softc->num_pages; i++)
 163                 softc->ramdisk_pages[i] = malloc(PAGE_SIZE, M_RAMDISK,M_WAITOK);
 164 #else
 165         softc->ramdisk_buffer = (uint8_t *)malloc(softc->rd_size, M_RAMDISK,
 166                                                   M_WAITOK);
 167 #endif
 168
 169         return (0);
 170 }
 171
 172 void
 173 ctl_backend_ramdisk_shutdown(void)
 174 {
 175         struct ctl_be_ramdisk_softc *softc;
 176         struct ctl_be_ramdisk_lun *lun, *next_lun;
 177 #ifdef CTL_RAMDISK_PAGES
 178         int i;
 179 #endif
 180
 181         softc = &rd_softc;
 182
 183         mtx_lock(&softc->lock);
 184         for (lun = STAILQ_FIRST(&softc->lun_list); lun != NULL; lun = next_lun){
 185                 /*
 186                  * Grab the next LUN.  The current LUN may get removed by
 187                  * ctl_invalidate_lun(), which will call our LUN shutdown
 188                  * routine, if there is no outstanding I/O for this LUN.
 189                  */
 190                 next_lun = STAILQ_NEXT(lun, links);
 191
 192                 /*
 193                  * Drop our lock here.  Since ctl_invalidate_lun() can call
 194                  * back into us, this could potentially lead to a recursive
 195                  * lock of the same mutex, which would cause a hang.
 196                  */
 197                 mtx_unlock(&softc->lock);
 198                 ctl_disable_lun(&lun->ctl_be_lun);
 199                 ctl_invalidate_lun(&lun->ctl_be_lun);
 200                 mtx_lock(&softc->lock);
 201         }
 202         mtx_unlock(&softc->lock);
 203
 204 #ifdef CTL_RAMDISK_PAGES
 205         for (i = 0; i < softc->num_pages; i++)
 206                 free(softc->ramdisk_pages[i], M_RAMDISK);
 207
 208         free(softc->ramdisk_pages, M_RAMDISK);
 209 #else
 210         free(softc->ramdisk_buffer, M_RAMDISK);
 211 #endif
 212
 213         if (ctl_backend_deregister(&ctl_be_ramdisk_driver) != 0) {
 214                 printf("ctl_backend_ramdisk_shutdown: "
 215                        "ctl_backend_deregister() failed!\n");
 216         }
 217 }
 218
 219 static int
 220 ctl_backend_ramdisk_move_done(union ctl_io *io)
 221 {
 222         struct ctl_be_lun *ctl_be_lun;
 223         struct ctl_be_ramdisk_lun *be_lun;
 224 #ifdef CTL_TIME_IO
 225         struct bintime cur_bt;
 226 #endif
 227
 228         CTL_DEBUG_PRINT(("ctl_backend_ramdisk_move_done\n"));
 229         ctl_be_lun = (struct ctl_be_lun *)io->io_hdr.ctl_private[
 230                 CTL_PRIV_BACKEND_LUN].ptr;
 231         be_lun = (struct ctl_be_ramdisk_lun *)ctl_be_lun->be_lun;
 232 #ifdef CTL_TIME_IO
 233         getbintime(&cur_bt);
 234         bintime_sub(&cur_bt, &io->io_hdr.dma_start_bt);
 235         bintime_add(&io->io_hdr.dma_bt, &cur_bt);
 236         io->io_hdr.num_dmas++;
 237 #endif
 238         if (io->scsiio.kern_sg_entries > 0)
 239                 free(io->scsiio.kern_data_ptr, M_RAMDISK);
 240         io->scsiio.kern_rel_offset += io->scsiio.kern_data_len;
 241         if ((io->io_hdr.port_status == 0)
 242          && ((io->io_hdr.flags & CTL_FLAG_ABORT) == 0)
 243          && ((io->io_hdr.status & CTL_STATUS_MASK) == CTL_STATUS_NONE)) {
 244                 if (io->io_hdr.ctl_private[CTL_PRIV_BACKEND].integer > 0) {
 245                         mtx_lock(&be_lun->lock);
 246                         STAILQ_INSERT_TAIL(&be_lun->cont_queue,
 247                             &io->io_hdr, links);
 248                         mtx_unlock(&be_lun->lock);
 249                         taskqueue_enqueue(be_lun->io_taskqueue,
 250                             &be_lun->io_task);
 251                         return (0);
 252                 }
 253                 io->io_hdr.status = CTL_SUCCESS;
 254         } else if ((io->io_hdr.port_status != 0)
 255               && ((io->io_hdr.flags & CTL_FLAG_ABORT) == 0)
 256               && ((io->io_hdr.status & CTL_STATUS_MASK) == CTL_STATUS_NONE)){
 257                 /*
 258                  * For hardware error sense keys, the sense key
 259                  * specific value is defined to be a retry count,
 260                  * but we use it to pass back an internal FETD
 261                  * error code.  XXX KDM  Hopefully the FETD is only
 262                  * using 16 bits for an error code, since that's
 263                  * all the space we have in the sks field.
 264                  */
 265                 ctl_set_internal_failure(&io->scsiio,
 266                                          /*sks_valid*/ 1,
 267                                          /*retry_count*/
 268                                          io->io_hdr.port_status);
 269         }
 270         ctl_done(io);
 271         return(0);
 272 }
 273
 274 static int
 275 ctl_backend_ramdisk_submit(union ctl_io *io)
 276 {
 277         struct ctl_be_lun *ctl_be_lun;
 278         struct ctl_lba_len *lbalen;
 279
 280         ctl_be_lun = (struct ctl_be_lun *)io->io_hdr.ctl_private[
 281                 CTL_PRIV_BACKEND_LUN].ptr;
 282         lbalen = (struct ctl_lba_len *)&io->io_hdr.ctl_private[CTL_PRIV_LBA_LEN];
 283         io->io_hdr.ctl_private[CTL_PRIV_BACKEND].integer =
 284             lbalen->len * ctl_be_lun->blocksize;
 285         ctl_backend_ramdisk_continue(io);
 286         return (CTL_RETVAL_COMPLETE);
 287 }
 288
 289 static void
 290 ctl_backend_ramdisk_continue(union ctl_io *io)
 291 {
 292         struct ctl_be_ramdisk_softc *softc;
 293         int len, len_filled, sg_filled;
 294 #ifdef CTL_RAMDISK_PAGES
 295         struct ctl_sg_entry *sg_entries;
 296         int i;
 297 #endif
 298
 299         softc = &rd_softc;
 300         len = io->io_hdr.ctl_private[CTL_PRIV_BACKEND].integer;
 301 #ifdef CTL_RAMDISK_PAGES
 302         sg_filled = min(btoc(len), softc->num_pages);
 303         if (sg_filled > 1) {
 304                 io->scsiio.kern_data_ptr = malloc(sizeof(struct ctl_sg_entry) *
 305                                                   sg_filled, M_RAMDISK,
 306                                                   M_WAITOK);
 307                 sg_entries = (struct ctl_sg_entry *)io->scsiio.kern_data_ptr;
 308                 for (i = 0, len_filled = 0; i < sg_filled; i++) {
 309                         sg_entries[i].addr = softc->ramdisk_pages[i];
 310                         sg_entries[i].len = ctl_min(PAGE_SIZE,
 311                                                     len - len_filled);
 312                         len_filled += sg_entries[i].len;
 313                 }
 314                 io->io_hdr.flags |= CTL_FLAG_KDPTR_SGLIST;
 315         } else {
 316                 sg_filled = 0;
 317                 len_filled = len;
 318                 io->scsiio.kern_data_ptr = softc->ramdisk_pages[0];
 319         }
 320 #else
 321         sg_filled = 0;
 322         len_filled = min(len, softc->rd_size);
 323         io->scsiio.kern_data_ptr = softc->ramdisk_buffer;
 324 #endif /* CTL_RAMDISK_PAGES */
 325
 326         io->scsiio.be_move_done = ctl_backend_ramdisk_move_done;
 327         io->scsiio.kern_data_resid = 0;
 328         io->scsiio.kern_data_len = len_filled;
 329         io->scsiio.kern_sg_entries = sg_filled;
 330         io->io_hdr.flags |= CTL_FLAG_ALLOCATED;
 331         io->io_hdr.ctl_private[CTL_PRIV_BACKEND].integer -= len_filled;
 332 #ifdef CTL_TIME_IO
 333         getbintime(&io->io_hdr.dma_start_bt);
 334 #endif
 335         ctl_datamove(io);
 336 }
 337
 338 static void
 339 ctl_backend_ramdisk_worker(void *context, int pending)
 340 {
 341         struct ctl_be_ramdisk_softc *softc;
 342         struct ctl_be_ramdisk_lun *be_lun;
 343         union ctl_io *io;
 344
 345         be_lun = (struct ctl_be_ramdisk_lun *)context;
 346         softc = be_lun->softc;
 347
 348         mtx_lock(&be_lun->lock);
 349         for (;;) {
 350                 io = (union ctl_io *)STAILQ_FIRST(&be_lun->cont_queue);
 351                 if (io != NULL) {
 352                         STAILQ_REMOVE(&be_lun->cont_queue, &io->io_hdr,
 353                                       ctl_io_hdr, links);
 354
 355                         mtx_unlock(&be_lun->lock);
 356
 357                         ctl_backend_ramdisk_continue(io);
 358
 359                         mtx_lock(&be_lun->lock);
 360                         continue;
 361                 }
 362
 363                 /*
 364                  * If we get here, there is no work left in the queues, so
 365                  * just break out and let the task queue go to sleep.
 366                  */
 367                 break;
 368         }
 369         mtx_unlock(&be_lun->lock);
 370 }
 371
 372 static int
 373 ctl_backend_ramdisk_ioctl(struct cdev *dev, u_long cmd, caddr_t addr,
 374                           int flag, struct thread *td)
 375 {
 376         struct ctl_be_ramdisk_softc *softc;
 377         int retval;
 378
 379         retval = 0;
 380         softc = &rd_softc;
 381
 382         switch (cmd) {
 383         case CTL_LUN_REQ: {
 384                 struct ctl_lun_req *lun_req;
 385
 386                 lun_req = (struct ctl_lun_req *)addr;
 387
 388                 switch (lun_req->reqtype) {
 389                 case CTL_LUNREQ_CREATE:
 390                         retval = ctl_backend_ramdisk_create(softc, lun_req,
 391                                                             /*do_wait*/ 1);
 392                         break;
 393                 case CTL_LUNREQ_RM:
 394                         retval = ctl_backend_ramdisk_rm(softc, lun_req);
 395                         break;
 396                 case CTL_LUNREQ_MODIFY:
 397                         retval = ctl_backend_ramdisk_modify(softc, lun_req);
 398                         break;
 399                 default:
 400                         lun_req->status = CTL_LUN_ERROR;
 401                         snprintf(lun_req->error_str, sizeof(lun_req->error_str),
 402                                  "%s: invalid LUN request type %d", __func__,
 403                                  lun_req->reqtype);
 404                         break;
 405                 }
 406                 break;
 407         }
 408         default:
 409                 retval = ENOTTY;
 410                 break;
 411         }
 412
 413         return (retval);
 414 }
 415
 416 static int
 417 ctl_backend_ramdisk_rm(struct ctl_be_ramdisk_softc *softc,
 418                        struct ctl_lun_req *req)
 419 {
 420         struct ctl_be_ramdisk_lun *be_lun;
 421         struct ctl_lun_rm_params *params;
 422         int retval;
 423
 424
 425         retval = 0;
 426         params = &req->reqdata.rm;
 427
 428         be_lun = NULL;
 429
 430         mtx_lock(&softc->lock);
 431
 432         STAILQ_FOREACH(be_lun, &softc->lun_list, links) {
 433                 if (be_lun->ctl_be_lun.lun_id == params->lun_id)
 434                         break;
 435         }
 436         mtx_unlock(&softc->lock);
 437
 438         if (be_lun == NULL) {
 439                 snprintf(req->error_str, sizeof(req->error_str),
 440                          "%s: LUN %u is not managed by the ramdisk backend",
 441                          __func__, params->lun_id);
 442                 goto bailout_error;
 443         }
 444
 445         retval = ctl_disable_lun(&be_lun->ctl_be_lun);
 446
 447         if (retval != 0) {
 448                 snprintf(req->error_str, sizeof(req->error_str),
 449                          "%s: error %d returned from ctl_disable_lun() for "
 450                          "LUN %d", __func__, retval, params->lun_id);
 451                 goto bailout_error;
 452         }
 453
 454         /*
 455          * Set the waiting flag before we invalidate the LUN.  Our shutdown
 456          * routine can be called any time after we invalidate the LUN,
 457          * and can be called from our context.
 458          *
 459          * This tells the shutdown routine that we're waiting, or we're
 460          * going to wait for the shutdown to happen.
 461          */
 462         mtx_lock(&softc->lock);
 463         be_lun->flags |= CTL_BE_RAMDISK_LUN_WAITING;
 464         mtx_unlock(&softc->lock);
 465
 466         retval = ctl_invalidate_lun(&be_lun->ctl_be_lun);
 467         if (retval != 0) {
 468                 snprintf(req->error_str, sizeof(req->error_str),
 469                          "%s: error %d returned from ctl_invalidate_lun() for "
 470                          "LUN %d", __func__, retval, params->lun_id);
 471                 mtx_lock(&softc->lock);
 472                 be_lun->flags &= ~CTL_BE_RAMDISK_LUN_WAITING;
 473                 mtx_unlock(&softc->lock);
 474                 goto bailout_error;
 475         }
 476
 477         mtx_lock(&softc->lock);
 478
 479         while ((be_lun->flags & CTL_BE_RAMDISK_LUN_UNCONFIGURED) == 0) {
 480                 retval = msleep(be_lun, &softc->lock, PCATCH, "ctlram", 0);
 481                 if (retval == EINTR)
 482                         break;
 483         }
 484         be_lun->flags &= ~CTL_BE_RAMDISK_LUN_WAITING;
 485
 486         /*
 487          * We only remove this LUN from the list and free it (below) if
 488          * retval == 0.  If the user interrupted the wait, we just bail out
 489          * without actually freeing the LUN.  We let the shutdown routine
 490          * free the LUN if that happens.
 491          */
 492         if (retval == 0) {
 493                 STAILQ_REMOVE(&softc->lun_list, be_lun, ctl_be_ramdisk_lun,
 494                               links);
 495                 softc->num_luns--;
 496         }
 497
 498         mtx_unlock(&softc->lock);
 499
 500         if (retval == 0) {
 501                 taskqueue_drain(be_lun->io_taskqueue, &be_lun->io_task);
 502                 taskqueue_free(be_lun->io_taskqueue);
 503                 ctl_free_opts(&be_lun->ctl_be_lun);
 504                 mtx_destroy(&be_lun->lock);
 505                 free(be_lun, M_RAMDISK);
 506         }
 507
 508         req->status = CTL_LUN_OK;
 509
 510         return (retval);
 511
 512 bailout_error:
 513         req->status = CTL_LUN_ERROR;
 514
 515         return (0);
 516 }
 517
 518 static int
 519 ctl_backend_ramdisk_create(struct ctl_be_ramdisk_softc *softc,
 520                            struct ctl_lun_req *req, int do_wait)
 521 {
 522         struct ctl_be_ramdisk_lun *be_lun;
 523         struct ctl_lun_create_params *params;
 524         uint32_t blocksize;
 525         char *value;
 526         char tmpstr[32];
 527         int retval, unmap;
 528
 529         retval = 0;
 530         params = &req->reqdata.create;
 531         if (params->blocksize_bytes != 0)
 532                 blocksize = params->blocksize_bytes;
 533         else
 534                 blocksize = 512;
 535
 536         be_lun = malloc(sizeof(*be_lun), M_RAMDISK, M_ZERO | (do_wait ?
 537                         M_WAITOK : M_NOWAIT));
 538
 539         if (be_lun == NULL) {
 540                 snprintf(req->error_str, sizeof(req->error_str),
 541                          "%s: error allocating %zd bytes", __func__,
 542                          sizeof(*be_lun));
 543                 goto bailout_error;
 544         }
 545         sprintf(be_lun->lunname, "cram%d", softc->num_luns);
 546         ctl_init_opts(&be_lun->ctl_be_lun, req);
 547
 548         if (params->flags & CTL_LUN_FLAG_DEV_TYPE)
 549                 be_lun->ctl_be_lun.lun_type = params->device_type;
 550         else
 551                 be_lun->ctl_be_lun.lun_type = T_DIRECT;
 552
 553         if (be_lun->ctl_be_lun.lun_type == T_DIRECT) {
 554
 555                 if (params->lun_size_bytes < blocksize) {
 556                         snprintf(req->error_str, sizeof(req->error_str),
 557                                  "%s: LUN size %ju < blocksize %u", __func__,
 558                                  params->lun_size_bytes, blocksize);
 559                         goto bailout_error;
 560                 }
 561
 562                 be_lun->size_blocks = params->lun_size_bytes / blocksize;
 563                 be_lun->size_bytes = be_lun->size_blocks * blocksize;
 564
 565                 be_lun->ctl_be_lun.maxlba = be_lun->size_blocks - 1;
 566         } else {
 567                 be_lun->ctl_be_lun.maxlba = 0;
 568                 blocksize = 0;
 569                 be_lun->size_bytes = 0;
 570                 be_lun->size_blocks = 0;
 571         }
 572
 573         be_lun->ctl_be_lun.blocksize = blocksize;
 574
 575         /* Tell the user the blocksize we ended up using */
 576         params->blocksize_bytes = blocksize;
 577
 578         /* Tell the user the exact size we ended up using */
 579         params->lun_size_bytes = be_lun->size_bytes;
 580
 581         be_lun->softc = softc;
 582
 583         unmap = 0;
 584         value = ctl_get_opt(&be_lun->ctl_be_lun, "unmap");
 585         if (value != NULL && strcmp(value, "on") == 0)
 586                 unmap = 1;
 587
 588         be_lun->flags = CTL_BE_RAMDISK_LUN_UNCONFIGURED;
 589         be_lun->ctl_be_lun.flags = CTL_LUN_FLAG_PRIMARY;
 590         if (unmap)
 591                 be_lun->ctl_be_lun.flags |= CTL_LUN_FLAG_UNMAP;
 592         be_lun->ctl_be_lun.be_lun = be_lun;
 593
 594         if (params->flags & CTL_LUN_FLAG_ID_REQ) {
 595                 be_lun->ctl_be_lun.req_lun_id = params->req_lun_id;
 596                 be_lun->ctl_be_lun.flags |= CTL_LUN_FLAG_ID_REQ;
 597         } else
 598                 be_lun->ctl_be_lun.req_lun_id = 0;
 599
 600         be_lun->ctl_be_lun.lun_shutdown = ctl_backend_ramdisk_lun_shutdown;
 601         be_lun->ctl_be_lun.lun_config_status =
 602                 ctl_backend_ramdisk_lun_config_status;
 603         be_lun->ctl_be_lun.be = &ctl_be_ramdisk_driver;
 604         if ((params->flags & CTL_LUN_FLAG_SERIAL_NUM) == 0) {
 605                 snprintf(tmpstr, sizeof(tmpstr), "MYSERIAL%4d",
 606                          softc->num_luns);
 607                 strncpy((char *)be_lun->ctl_be_lun.serial_num, tmpstr,
 608                         ctl_min(sizeof(be_lun->ctl_be_lun.serial_num),
 609                         sizeof(tmpstr)));
 610
 611                 /* Tell the user what we used for a serial number */
 612                 strncpy((char *)params->serial_num, tmpstr,
 613                         ctl_min(sizeof(params->serial_num), sizeof(tmpstr)));
 614         } else {
 615                 strncpy((char *)be_lun->ctl_be_lun.serial_num,
 616                         params->serial_num,
 617                         ctl_min(sizeof(be_lun->ctl_be_lun.serial_num),
 618                         sizeof(params->serial_num)));
 619         }
 620         if ((params->flags & CTL_LUN_FLAG_DEVID) == 0) {
 621                 snprintf(tmpstr, sizeof(tmpstr), "MYDEVID%4d", softc->num_luns);
 622                 strncpy((char *)be_lun->ctl_be_lun.device_id, tmpstr,
 623                         ctl_min(sizeof(be_lun->ctl_be_lun.device_id),
 624                         sizeof(tmpstr)));
 625
 626                 /* Tell the user what we used for a device ID */
 627                 strncpy((char *)params->device_id, tmpstr,
 628                         ctl_min(sizeof(params->device_id), sizeof(tmpstr)));
 629         } else {
 630                 strncpy((char *)be_lun->ctl_be_lun.device_id,
 631                         params->device_id,
 632                         ctl_min(sizeof(be_lun->ctl_be_lun.device_id),
 633                                 sizeof(params->device_id)));
 634         }
 635
 636         STAILQ_INIT(&be_lun->cont_queue);
 637         mtx_init(&be_lun->lock, "CTL ramdisk", NULL, MTX_DEF);
 638         TASK_INIT(&be_lun->io_task, /*priority*/0, ctl_backend_ramdisk_worker,
 639             be_lun);
 640
 641         be_lun->io_taskqueue = taskqueue_create(be_lun->lunname, M_WAITOK,
 642             taskqueue_thread_enqueue, /*context*/&be_lun->io_taskqueue);
 643         if (be_lun->io_taskqueue == NULL) {
 644                 snprintf(req->error_str, sizeof(req->error_str),
 645                          "%s: Unable to create taskqueue", __func__);
 646                 goto bailout_error;
 647         }
 648
 649         retval = taskqueue_start_threads(&be_lun->io_taskqueue,
 650                                          /*num threads*/1,
 651                                          /*priority*/PWAIT,
 652                                          /*thread name*/
 653                                          "%s taskq", be_lun->lunname);
 654         if (retval != 0)
 655                 goto bailout_error;
 656
 657         mtx_lock(&softc->lock);
 658         softc->num_luns++;
 659         STAILQ_INSERT_TAIL(&softc->lun_list, be_lun, links);
 660
 661         mtx_unlock(&softc->lock);
 662
 663         retval = ctl_add_lun(&be_lun->ctl_be_lun);
 664         if (retval != 0) {
 665                 mtx_lock(&softc->lock);
 666                 STAILQ_REMOVE(&softc->lun_list, be_lun, ctl_be_ramdisk_lun,
 667                               links);
 668                 softc->num_luns--;
 669                 mtx_unlock(&softc->lock);
 670                 snprintf(req->error_str, sizeof(req->error_str),
 671                          "%s: ctl_add_lun() returned error %d, see dmesg for "
 672                         "details", __func__, retval);
 673                 retval = 0;
 674                 goto bailout_error;
 675         }
 676
 677         if (do_wait == 0)
 678                 return (retval);
 679
 680         mtx_lock(&softc->lock);
 681
 682         /*
 683          * Tell the config_status routine that we're waiting so it won't
 684          * clean up the LUN in the event of an error.
 685          */
 686         be_lun->flags |= CTL_BE_RAMDISK_LUN_WAITING;
 687
 688         while (be_lun->flags & CTL_BE_RAMDISK_LUN_UNCONFIGURED) {
 689                 retval = msleep(be_lun, &softc->lock, PCATCH, "ctlram", 0);
 690                 if (retval == EINTR)
 691                         break;
 692         }
 693         be_lun->flags &= ~CTL_BE_RAMDISK_LUN_WAITING;
 694
 695         if (be_lun->flags & CTL_BE_RAMDISK_LUN_CONFIG_ERR) {
 696                 snprintf(req->error_str, sizeof(req->error_str),
 697                          "%s: LUN configuration error, see dmesg for details",
 698                          __func__);
 699                 STAILQ_REMOVE(&softc->lun_list, be_lun, ctl_be_ramdisk_lun,
 700                               links);
 701                 softc->num_luns--;
 702                 mtx_unlock(&softc->lock);
 703                 goto bailout_error;
 704         } else {
 705                 params->req_lun_id = be_lun->ctl_be_lun.lun_id;
 706         }
 707         mtx_unlock(&softc->lock);
 708
 709         req->status = CTL_LUN_OK;
 710
 711         return (retval);
 712
 713 bailout_error:
 714         req->status = CTL_LUN_ERROR;
 715         if (be_lun != NULL) {
 716                 if (be_lun->io_taskqueue != NULL) {
 717                         taskqueue_free(be_lun->io_taskqueue);
 718                 }
 719                 ctl_free_opts(&be_lun->ctl_be_lun);
 720                 mtx_destroy(&be_lun->lock);
 721                 free(be_lun, M_RAMDISK);
 722         }
 723
 724         return (retval);
 725 }
 726
 727 static int
 728 ctl_backend_ramdisk_modify(struct ctl_be_ramdisk_softc *softc,
 729                        struct ctl_lun_req *req)
 730 {
 731         struct ctl_be_ramdisk_lun *be_lun;
 732         struct ctl_lun_modify_params *params;
 733         uint32_t blocksize;
 734
 735         params = &req->reqdata.modify;
 736
 737         be_lun = NULL;
 738
 739         mtx_lock(&softc->lock);
 740         STAILQ_FOREACH(be_lun, &softc->lun_list, links) {
 741                 if (be_lun->ctl_be_lun.lun_id == params->lun_id)
 742                         break;
 743         }
 744         mtx_unlock(&softc->lock);
 745
 746         if (be_lun == NULL) {
 747                 snprintf(req->error_str, sizeof(req->error_str),
 748                          "%s: LUN %u is not managed by the ramdisk backend",
 749                          __func__, params->lun_id);
 750                 goto bailout_error;
 751         }
 752
 753         if (params->lun_size_bytes == 0) {
 754                 snprintf(req->error_str, sizeof(req->error_str),
 755                         "%s: LUN size \"auto\" not supported "
 756                         "by the ramdisk backend", __func__);
 757                 goto bailout_error;
 758         }
 759
 760         blocksize = be_lun->ctl_be_lun.blocksize;
 761
 762         if (params->lun_size_bytes < blocksize) {
 763                 snprintf(req->error_str, sizeof(req->error_str),
 764                         "%s: LUN size %ju < blocksize %u", __func__,
 765                         params->lun_size_bytes, blocksize);
 766                 goto bailout_error;
 767         }
 768
 769         be_lun->size_blocks = params->lun_size_bytes / blocksize;
 770         be_lun->size_bytes = be_lun->size_blocks * blocksize;
 771
 772         /*
 773          * The maximum LBA is the size - 1.
 774          *
 775          * XXX: Note that this field is being updated without locking,
 776          *      which might cause problems on 32-bit architectures.
 777          */
 778         be_lun->ctl_be_lun.maxlba = be_lun->size_blocks - 1;
 779         ctl_lun_capacity_changed(&be_lun->ctl_be_lun);
 780
 781         /* Tell the user the exact size we ended up using */
 782         params->lun_size_bytes = be_lun->size_bytes;
 783
 784         req->status = CTL_LUN_OK;
 785
 786         return (0);
 787
 788 bailout_error:
 789         req->status = CTL_LUN_ERROR;
 790
 791         return (0);
 792 }
 793
 794 static void
 795 ctl_backend_ramdisk_lun_shutdown(void *be_lun)
 796 {
 797         struct ctl_be_ramdisk_lun *lun;
 798         struct ctl_be_ramdisk_softc *softc;
 799         int do_free;
 800
 801         lun = (struct ctl_be_ramdisk_lun *)be_lun;
 802         softc = lun->softc;
 803         do_free = 0;
 804
 805         mtx_lock(&softc->lock);
 806
 807         lun->flags |= CTL_BE_RAMDISK_LUN_UNCONFIGURED;
 808
 809         if (lun->flags & CTL_BE_RAMDISK_LUN_WAITING) {
 810                 wakeup(lun);
 811         } else {
 812                 STAILQ_REMOVE(&softc->lun_list, be_lun, ctl_be_ramdisk_lun,
 813                               links);
 814                 softc->num_luns--;
 815                 do_free = 1;
 816         }
 817
 818         mtx_unlock(&softc->lock);
 819
 820         if (do_free != 0)
 821                 free(be_lun, M_RAMDISK);
 822 }
 823
 824 static void
 825 ctl_backend_ramdisk_lun_config_status(void *be_lun,
 826                                       ctl_lun_config_status status)
 827 {
 828         struct ctl_be_ramdisk_lun *lun;
 829         struct ctl_be_ramdisk_softc *softc;
 830
 831         lun = (struct ctl_be_ramdisk_lun *)be_lun;
 832         softc = lun->softc;
 833
 834         if (status == CTL_LUN_CONFIG_OK) {
 835                 mtx_lock(&softc->lock);
 836                 lun->flags &= ~CTL_BE_RAMDISK_LUN_UNCONFIGURED;
 837                 if (lun->flags & CTL_BE_RAMDISK_LUN_WAITING)
 838                         wakeup(lun);
 839                 mtx_unlock(&softc->lock);
 840
 841                 /*
 842                  * We successfully added the LUN, attempt to enable it.
 843                  */
 844                 if (ctl_enable_lun(&lun->ctl_be_lun) != 0) {
 845                         printf("%s: ctl_enable_lun() failed!\n", __func__);
 846                         if (ctl_invalidate_lun(&lun->ctl_be_lun) != 0) {
 847                                 printf("%s: ctl_invalidate_lun() failed!\n",
 848                                        __func__);
 849                         }
 850                 }
 851
 852                 return;
 853         }
 854
 855
 856         mtx_lock(&softc->lock);
 857         lun->flags &= ~CTL_BE_RAMDISK_LUN_UNCONFIGURED;
 858
 859         /*
 860          * If we have a user waiting, let him handle the cleanup.  If not,
 861          * clean things up here.
 862          */
 863         if (lun->flags & CTL_BE_RAMDISK_LUN_WAITING) {
 864                 lun->flags |= CTL_BE_RAMDISK_LUN_CONFIG_ERR;
 865                 wakeup(lun);
 866         } else {
 867                 STAILQ_REMOVE(&softc->lun_list, lun, ctl_be_ramdisk_lun,
 868                               links);
 869                 softc->num_luns--;
 870                 free(lun, M_RAMDISK);
 871         }
 872         mtx_unlock(&softc->lock);
 873 }
 874
 875 static int
 876 ctl_backend_ramdisk_config_write(union ctl_io *io)
 877 {
 878         struct ctl_be_ramdisk_softc *softc;
 879         int retval;
 880
 881         retval = 0;
 882         softc = &rd_softc;
 883
 884         switch (io->scsiio.cdb[0]) {
 885         case SYNCHRONIZE_CACHE:
 886         case SYNCHRONIZE_CACHE_16:
 887                 /*
 888                  * The upper level CTL code will filter out any CDBs with
 889                  * the immediate bit set and return the proper error.  It
 890                  * will also not allow a sync cache command to go to a LUN
 891                  * that is powered down.
 892                  *
 893                  * We don't really need to worry about what LBA range the
 894                  * user asked to be synced out.  When they issue a sync
 895                  * cache command, we'll sync out the whole thing.
 896                  *
 897                  * This is obviously just a stubbed out implementation.
 898                  * The real implementation will be in the RAIDCore/CTL
 899                  * interface, and can only really happen when RAIDCore
 900                  * implements a per-array cache sync.
 901                  */
 902                 ctl_set_success(&io->scsiio);
 903                 ctl_config_write_done(io);
 904                 break;
 905         case START_STOP_UNIT: {
 906                 struct scsi_start_stop_unit *cdb;
 907                 struct ctl_be_lun *ctl_be_lun;
 908                 struct ctl_be_ramdisk_lun *be_lun;
 909
 910                 cdb = (struct scsi_start_stop_unit *)io->scsiio.cdb;
 911
 912                 ctl_be_lun = (struct ctl_be_lun *)io->io_hdr.ctl_private[
 913                         CTL_PRIV_BACKEND_LUN].ptr;
 914                 be_lun = (struct ctl_be_ramdisk_lun *)ctl_be_lun->be_lun;
 915
 916                 if (cdb->how & SSS_START)
 917                         retval = ctl_start_lun(ctl_be_lun);
 918                 else {
 919                         retval = ctl_stop_lun(ctl_be_lun);
 920 #ifdef NEEDTOPORT
 921                         if ((retval == 0)
 922                          && (cdb->byte2 & SSS_ONOFFLINE))
 923                                 retval = ctl_lun_offline(ctl_be_lun);
 924 #endif
 925                 }
 926
 927                 /*
 928                  * In general, the above routines should not fail.  They
 929                  * just set state for the LUN.  So we've got something
 930                  * pretty wrong here if we can't start or stop the LUN.
 931                  */
 932                 if (retval != 0) {
 933                         ctl_set_internal_failure(&io->scsiio,
 934                                                  /*sks_valid*/ 1,
 935                                                  /*retry_count*/ 0xf051);
 936                         retval = CTL_RETVAL_COMPLETE;
 937                 } else {
 938                         ctl_set_success(&io->scsiio);
 939                 }
 940                 ctl_config_write_done(io);
 941                 break;
 942         }
 943         case WRITE_SAME_10:
 944         case WRITE_SAME_16:
 945         case UNMAP:
 946                 ctl_set_success(&io->scsiio);
 947                 ctl_config_write_done(io);
 948                 break;
 949         default:
 950                 ctl_set_invalid_opcode(&io->scsiio);
 951                 ctl_config_write_done(io);
 952                 retval = CTL_RETVAL_COMPLETE;
 953                 break;
 954         }
 955
 956         return (retval);
 957 }
 958
 959 static int
 960 ctl_backend_ramdisk_config_read(union ctl_io *io)
 961 {
 962         /*
 963          * XXX KDM need to implement!!
 964          */
 965         return (0);
 966 }