sys/kern/subr_diskiocom.c

   1 /*
   2  * Copyright (c) 2012 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Matthew Dillon <dillon@backplane.com>
   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  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  * 3. Neither the name of The DragonFly Project nor the names of its
  18  *    contributors may be used to endorse or promote products derived
  19  *    from this software without specific, prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  */
  34 #include <sys/param.h>
  35 #include <sys/systm.h>
  36 #include <sys/kernel.h>
  37 #include <sys/proc.h>
  38 #include <sys/sysctl.h>
  39 #include <sys/buf.h>
  40 #include <sys/conf.h>
  41 #include <sys/disklabel.h>
  42 #include <sys/disklabel32.h>
  43 #include <sys/disklabel64.h>
  44 #include <sys/diskslice.h>
  45 #include <sys/diskmbr.h>
  46 #include <sys/disk.h>
  47 #include <sys/malloc.h>
  48 #include <sys/device.h>
  49 #include <sys/devfs.h>
  50 #include <sys/thread.h>
  51 #include <sys/queue.h>
  52 #include <sys/lock.h>
  53 #include <sys/stat.h>
  54 #include <sys/uuid.h>
  55 #include <sys/dmsg.h>
  56
  57 #include <sys/buf2.h>
  58 #include <sys/mplock2.h>
  59 #include <sys/msgport2.h>
  60 #include <sys/thread2.h>
  61
  62 struct dios_open {
  63         int     openrd;
  64         int     openwr;
  65 };
  66
  67 struct dios_io {
  68         int     count;
  69         int     eof;
  70         kdmsg_data_t data;
  71 };
  72
  73 static MALLOC_DEFINE(M_DMSG_DISK, "dmsg_disk", "disk dmsg");
  74
  75 static int blk_active;
  76 SYSCTL_INT(_debug, OID_AUTO, blk_active, CTLFLAG_RW, &blk_active, 0,
  77            "Number of active iocom IOs");
  78
  79 static int disk_iocom_reconnect(struct disk *dp, struct file *fp);
  80 static int disk_rcvdmsg(kdmsg_msg_t *msg);
  81
  82 static void disk_blk_open(struct disk *dp, kdmsg_msg_t *msg);
  83 static void disk_blk_read(struct disk *dp, kdmsg_msg_t *msg);
  84 static void disk_blk_write(struct disk *dp, kdmsg_msg_t *msg);
  85 static void disk_blk_flush(struct disk *dp, kdmsg_msg_t *msg);
  86 static void disk_blk_freeblks(struct disk *dp, kdmsg_msg_t *msg);
  87 static void diskiodone(struct bio *bio);
  88
  89 void
  90 disk_iocom_init(struct disk *dp)
  91 {
  92         kdmsg_iocom_init(&dp->d_iocom, dp,
  93                          KDMSG_IOCOMF_AUTOCONN |
  94                          KDMSG_IOCOMF_AUTORXSPAN |
  95                          KDMSG_IOCOMF_AUTOTXSPAN,
  96                          M_DMSG_DISK, disk_rcvdmsg);
  97 }
  98
  99 void
 100 disk_iocom_update(struct disk *dp)
 101 {
 102 }
 103
 104 void
 105 disk_iocom_uninit(struct disk *dp)
 106 {
 107         kdmsg_iocom_uninit(&dp->d_iocom);
 108 }
 109
 110 int
 111 disk_iocom_ioctl(struct disk *dp, int cmd, void *data)
 112 {
 113         struct file *fp;
 114         struct disk_ioc_recluster *recl;
 115         int error;
 116
 117         switch(cmd) {
 118         case DIOCRECLUSTER:
 119                 recl = data;
 120                 fp = holdfp(curproc->p_fd, recl->fd, -1);
 121                 if (fp) {
 122                         error = disk_iocom_reconnect(dp, fp);
 123                 } else {
 124                         error = EINVAL;
 125                 }
 126                 break;
 127         default:
 128                 error = EOPNOTSUPP;
 129                 break;
 130         }
 131         return error;
 132 }
 133
 134 static
 135 int
 136 disk_iocom_reconnect(struct disk *dp, struct file *fp)
 137 {
 138         char devname[64];
 139
 140         ksnprintf(devname, sizeof(devname), "%s%d",
 141                   dev_dname(dp->d_rawdev), dkunit(dp->d_rawdev));
 142
 143         kdmsg_iocom_reconnect(&dp->d_iocom, fp, devname);
 144
 145         dp->d_iocom.auto_lnk_conn.proto_version = DMSG_SPAN_PROTO_1;
 146         dp->d_iocom.auto_lnk_conn.peer_type = DMSG_PEER_BLOCK;
 147         dp->d_iocom.auto_lnk_conn.peer_mask = 1LLU << DMSG_PEER_BLOCK;
 148         dp->d_iocom.auto_lnk_conn.peer_mask = (uint64_t)-1;
 149 #if 0
 150         if (dp->d_info.d_serialno) {
 151                 ksnprintf(dp->d_iocom.auto_lnk_conn.peer_label,
 152                           sizeof(dp->d_iocom.auto_lnk_conn.peer_label),
 153                           "%s/%s", hostname, dp->d_info.d_serialno);
 154         } else {
 155                 ksnprintf(dp->d_iocom.auto_lnk_conn.peer_label,
 156                           sizeof(dp->d_iocom.auto_lnk_conn.peer_label),
 157                           "%s/%s", hostname, devname);
 158         }
 159 #endif
 160         ksnprintf(dp->d_iocom.auto_lnk_conn.peer_label,
 161                   sizeof(dp->d_iocom.auto_lnk_conn.peer_label),
 162                   "%s/%s", hostname, devname);
 163
 164         dp->d_iocom.auto_lnk_span.proto_version = DMSG_SPAN_PROTO_1;
 165         dp->d_iocom.auto_lnk_span.peer_type = DMSG_PEER_BLOCK;
 166         dp->d_iocom.auto_lnk_span.media.block.bytes =
 167                                                 dp->d_info.d_media_size;
 168         dp->d_iocom.auto_lnk_span.media.block.blksize =
 169                                                 dp->d_info.d_media_blksize;
 170         ksnprintf(dp->d_iocom.auto_lnk_span.peer_label,
 171                   sizeof(dp->d_iocom.auto_lnk_span.peer_label),
 172                   "%s", dp->d_iocom.auto_lnk_conn.peer_label);
 173         if (dp->d_info.d_serialno) {
 174                 ksnprintf(dp->d_iocom.auto_lnk_span.pfs_label,
 175                           sizeof(dp->d_iocom.auto_lnk_span.pfs_label),
 176                           "%s", dp->d_info.d_serialno);
 177         } else {
 178                 /*
 179                  * If no serial number is available generate a dummy serial
 180                  * number from the host and device name and pray.  This will
 181                  * allow e.g. /dev/vn* to look meaningful on a remote machine.
 182                  */
 183                 ksnprintf(dp->d_iocom.auto_lnk_span.pfs_label,
 184                           sizeof(dp->d_iocom.auto_lnk_span.pfs_label),
 185                           "%s.%s", hostname, devname);
 186         }
 187
 188         kdmsg_iocom_autoinitiate(&dp->d_iocom, NULL);
 189
 190         return (0);
 191 }
 192
 193 static int
 194 disk_rcvdmsg(kdmsg_msg_t *msg)
 195 {
 196         struct disk *dp = msg->state->iocom->handle;
 197
 198         /*
 199          * Handle debug messages (these might not be in transactions)
 200          */
 201         switch(msg->any.head.cmd & DMSGF_CMDSWMASK) {
 202         case DMSG_DBG_SHELL:
 203                 /*
 204                  * Execute shell command (not supported atm)
 205                  */
 206                 kdmsg_msg_reply(msg, DMSG_ERR_NOSUPP);
 207                 return(0);
 208         case DMSG_DBG_SHELL | DMSGF_REPLY:
 209                 if (msg->aux_data) {
 210                         msg->aux_data[msg->aux_size - 1] = 0;
 211                         kprintf("diskiocom: DEBUGMSG: %s\n", msg->aux_data);
 212                 }
 213                 return(0);
 214         }
 215
 216         /*
 217          * All remaining messages must be in a transaction.
 218          *
 219          * NOTE!  We currently don't care if the transaction is just
 220          *        the span transaction (for disk probes) or if it is the
 221          *        BLK_OPEN transaction.
 222          *
 223          * NOTE!  We are switching on the first message's command.  The
 224          *        actual message command within the transaction may be
 225          *        different (if streaming within a transaction).
 226          */
 227         if (msg->state == &msg->state->iocom->state0) {
 228                 kdmsg_msg_reply(msg, DMSG_ERR_NOSUPP);
 229                 return(0);
 230         }
 231
 232         switch(msg->state->rxcmd & DMSGF_CMDSWMASK) {
 233         case DMSG_BLK_OPEN:
 234                 disk_blk_open(dp, msg);
 235                 break;
 236         case DMSG_BLK_READ:
 237                 /*
 238                  * not reached normally but leave in for completeness
 239                  */
 240                 disk_blk_read(dp, msg);
 241                 break;
 242         case DMSG_BLK_WRITE:
 243                 disk_blk_write(dp, msg);
 244                 break;
 245         case DMSG_BLK_FLUSH:
 246                 disk_blk_flush(dp, msg);
 247                 break;
 248         case DMSG_BLK_FREEBLKS:
 249                 disk_blk_freeblks(dp, msg);
 250                 break;
 251         default:
 252                 if ((msg->any.head.cmd & DMSGF_REPLY) == 0) {
 253                         if (msg->any.head.cmd & DMSGF_DELETE)
 254                                 kdmsg_msg_reply(msg, DMSG_ERR_NOSUPP);
 255                         else
 256                                 kdmsg_msg_result(msg, DMSG_ERR_NOSUPP);
 257                 }
 258                 break;
 259         }
 260         return (0);
 261 }
 262
 263 static
 264 void
 265 disk_blk_open(struct disk *dp, kdmsg_msg_t *msg)
 266 {
 267         struct dios_open *openst;
 268         int error = DMSG_ERR_NOSUPP;
 269         int fflags;
 270
 271         openst = msg->state->any.any;
 272         if ((msg->any.head.cmd & DMSGF_CMDSWMASK) == DMSG_BLK_OPEN) {
 273                 if (openst == NULL) {
 274                         openst = kmalloc(sizeof(*openst), M_DEVBUF,
 275                                                 M_WAITOK | M_ZERO);
 276                         msg->state->any.any = openst;
 277                 }
 278                 fflags = 0;
 279                 if (msg->any.blk_open.modes & DMSG_BLKOPEN_RD)
 280                         fflags = FREAD;
 281                 if (msg->any.blk_open.modes & DMSG_BLKOPEN_WR)
 282                         fflags |= FWRITE;
 283                 error = dev_dopen(dp->d_rawdev, fflags, S_IFCHR, proc0.p_ucred, NULL);
 284                 if (error) {
 285                         error = DMSG_ERR_IO;
 286                 } else {
 287                         if (msg->any.blk_open.modes & DMSG_BLKOPEN_RD)
 288                                 ++openst->openrd;
 289                         if (msg->any.blk_open.modes & DMSG_BLKOPEN_WR)
 290                                 ++openst->openwr;
 291                 }
 292         }
 293 #if 0
 294         if ((msg->any.head.cmd & DMSGF_CMDSWMASK) == DMSG_BLK_CLOSE &&
 295             openst) {
 296                 fflags = 0;
 297                 if ((msg->any.blk_open.modes & DMSG_BLKOPEN_RD) &&
 298                     openst->openrd) {
 299                         fflags = FREAD;
 300                 }
 301                 if ((msg->any.blk_open.modes & DMSG_BLKOPEN_WR) &&
 302                     openst->openwr) {
 303                         fflags |= FWRITE;
 304                 }
 305                 error = dev_dclose(dp->d_rawdev, fflags, S_IFCHR, NULL);
 306                 if (error) {
 307                         error = DMSG_ERR_IO;
 308                 } else {
 309                         if (msg->any.blk_open.modes & DMSG_BLKOPEN_RD)
 310                                 --openst->openrd;
 311                         if (msg->any.blk_open.modes & DMSG_BLKOPEN_WR)
 312                                 --openst->openwr;
 313                 }
 314         }
 315 #endif
 316         if (msg->any.head.cmd & DMSGF_DELETE) {
 317                 if (openst) {
 318                         while (openst->openrd && openst->openwr) {
 319                                 --openst->openrd;
 320                                 --openst->openwr;
 321                                 dev_dclose(dp->d_rawdev, FREAD|FWRITE, S_IFCHR, NULL);
 322                         }
 323                         while (openst->openrd) {
 324                                 --openst->openrd;
 325                                 dev_dclose(dp->d_rawdev, FREAD, S_IFCHR, NULL);
 326                         }
 327                         while (openst->openwr) {
 328                                 --openst->openwr;
 329                                 dev_dclose(dp->d_rawdev, FWRITE, S_IFCHR, NULL);
 330                         }
 331                         kfree(openst, M_DEVBUF);
 332                         msg->state->any.any = NULL;
 333                 }
 334                 kdmsg_msg_reply(msg, error);
 335         } else {
 336                 kdmsg_msg_result(msg, error);
 337         }
 338 }
 339
 340 static
 341 void
 342 disk_blk_read(struct disk *dp, kdmsg_msg_t *msg)
 343 {
 344         struct dios_io *iost;
 345         struct buf *bp;
 346         struct bio *bio;
 347         int error = DMSG_ERR_NOSUPP;
 348         int reterr = 1;
 349
 350         /*
 351          * Only DMSG_BLK_READ commands imply read ops.
 352          */
 353         iost = msg->state->any.any;
 354         if ((msg->any.head.cmd & DMSGF_CMDSWMASK) == DMSG_BLK_READ) {
 355                 if (msg->any.blk_read.bytes < DEV_BSIZE ||
 356                     msg->any.blk_read.bytes > MAXPHYS) {
 357                         error = DMSG_ERR_PARAM;
 358                         goto done;
 359                 }
 360                 if (iost == NULL) {
 361                         iost = kmalloc(sizeof(*iost), M_DEVBUF,
 362                                        M_WAITOK | M_ZERO);
 363                         msg->state->any.any = iost;
 364                 }
 365                 reterr = 0;
 366                 bp = geteblk(msg->any.blk_read.bytes);
 367                 bio = &bp->b_bio1;
 368                 bp->b_cmd = BUF_CMD_READ;
 369                 bp->b_bcount = msg->any.blk_read.bytes;
 370                 bp->b_resid = bp->b_bcount;
 371                 bio->bio_offset = msg->any.blk_read.offset;
 372                 bio->bio_caller_info1.ptr = msg->state;
 373                 bio->bio_done = diskiodone;
 374
 375                 /* kdmsg_state_hold(msg->state); */
 376                 atomic_add_int(&blk_active, 1);
 377                 atomic_add_int(&iost->count, 1);
 378                 if (msg->any.head.cmd & DMSGF_DELETE)
 379                         iost->eof = 1;
 380                 BUF_KERNPROC(bp);
 381                 dev_dstrategy(dp->d_rawdev, bio);
 382         }
 383 done:
 384         if (reterr) {
 385                 if (msg->any.head.cmd & DMSGF_DELETE) {
 386                         if (iost && iost->count == 0) {
 387                                 kfree(iost, M_DEVBUF);
 388                                 msg->state->any.any = NULL;
 389                         }
 390                         kdmsg_msg_reply(msg, error);
 391                 } else {
 392                         kdmsg_msg_result(msg, error);
 393                 }
 394         }
 395 }
 396
 397 static
 398 void
 399 disk_blk_write(struct disk *dp, kdmsg_msg_t *msg)
 400 {
 401         struct dios_io *iost;
 402         struct buf *bp;
 403         struct bio *bio;
 404         int error = DMSG_ERR_NOSUPP;
 405         int reterr = 1;
 406
 407         /*
 408          * Only DMSG_BLK_WRITE commands imply read ops.
 409          */
 410         iost = msg->state->any.any;
 411         if ((msg->any.head.cmd & DMSGF_CMDSWMASK) == DMSG_BLK_WRITE) {
 412                 if (msg->any.blk_write.bytes < DEV_BSIZE ||
 413                     msg->any.blk_write.bytes > MAXPHYS) {
 414                         error = DMSG_ERR_PARAM;
 415                         goto done;
 416                 }
 417                 if (iost == NULL) {
 418                         iost = kmalloc(sizeof(*iost), M_DEVBUF,
 419                                        M_WAITOK | M_ZERO);
 420                         msg->state->any.any = iost;
 421                 }
 422
 423                 /*
 424                  * Issue WRITE.  Short data implies zeros.  Try to optimize
 425                  * the buffer cache buffer for the case where we can just
 426                  * use the message's data pointer.
 427                  */
 428                 reterr = 0;
 429                 if (msg->aux_size >= msg->any.blk_write.bytes)
 430                         bp = getpbuf(NULL);
 431                 else
 432                         bp = geteblk(msg->any.blk_write.bytes);
 433                 bio = &bp->b_bio1;
 434                 bp->b_cmd = BUF_CMD_WRITE;
 435                 bp->b_bcount = msg->any.blk_write.bytes;
 436                 bp->b_resid = bp->b_bcount;
 437                 if (msg->aux_size >= msg->any.blk_write.bytes) {
 438                         bp->b_data = msg->aux_data;
 439                         kdmsg_detach_aux_data(msg, &iost->data);
 440                 } else {
 441                         bcopy(msg->aux_data, bp->b_data, msg->aux_size);
 442                         bzero(bp->b_data + msg->aux_size,
 443                               msg->any.blk_write.bytes - msg->aux_size);
 444                         bzero(&iost->data, sizeof(iost->data));
 445                 }
 446                 bio->bio_offset = msg->any.blk_write.offset;
 447                 bio->bio_caller_info1.ptr = msg->state;
 448                 bio->bio_done = diskiodone;
 449
 450                 /* kdmsg_state_hold(msg->state); */
 451                 atomic_add_int(&blk_active, 1);
 452                 atomic_add_int(&iost->count, 1);
 453                 if (msg->any.head.cmd & DMSGF_DELETE)
 454                         iost->eof = 1;
 455                 BUF_KERNPROC(bp);
 456                 dev_dstrategy(dp->d_rawdev, bio);
 457         }
 458 done:
 459         if (reterr) {
 460                 if (msg->any.head.cmd & DMSGF_DELETE) {
 461                         if (iost && iost->count == 0) {
 462                                 kfree(iost, M_DEVBUF);
 463                                 msg->state->any.any = NULL;
 464                         }
 465                         kdmsg_msg_reply(msg, error);
 466                 } else {
 467                         kdmsg_msg_result(msg, error);
 468                 }
 469         }
 470 }
 471
 472 static
 473 void
 474 disk_blk_flush(struct disk *dp, kdmsg_msg_t *msg)
 475 {
 476         struct dios_io *iost;
 477         struct buf *bp;
 478         struct bio *bio;
 479         int error = DMSG_ERR_NOSUPP;
 480         int reterr = 1;
 481
 482         /*
 483          * Only DMSG_BLK_FLUSH commands imply read ops.
 484          */
 485         iost = msg->state->any.any;
 486         if ((msg->any.head.cmd & DMSGF_CMDSWMASK) == DMSG_BLK_FLUSH) {
 487                 if (iost == NULL) {
 488                         iost = kmalloc(sizeof(*iost), M_DEVBUF,
 489                                        M_WAITOK | M_ZERO);
 490                         msg->state->any.any = iost;
 491                 }
 492                 reterr = 0;
 493                 bp = getpbuf(NULL);
 494                 bio = &bp->b_bio1;
 495                 bp->b_cmd = BUF_CMD_FLUSH;
 496                 bp->b_bcount = msg->any.blk_flush.bytes;
 497                 bp->b_resid = 0;
 498                 bio->bio_offset = msg->any.blk_flush.offset;
 499                 bio->bio_caller_info1.ptr = msg->state;
 500                 bio->bio_done = diskiodone;
 501
 502                 /* kdmsg_state_hold(msg->state); */
 503                 atomic_add_int(&blk_active, 1);
 504                 atomic_add_int(&iost->count, 1);
 505                 if (msg->any.head.cmd & DMSGF_DELETE)
 506                         iost->eof = 1;
 507                 BUF_KERNPROC(bp);
 508                 dev_dstrategy(dp->d_rawdev, bio);
 509         }
 510         if (reterr) {
 511                 if (msg->any.head.cmd & DMSGF_DELETE) {
 512                         if (iost && iost->count == 0) {
 513                                 kfree(iost, M_DEVBUF);
 514                                 msg->state->any.any = NULL;
 515                         }
 516                         kdmsg_msg_reply(msg, error);
 517                 } else {
 518                         kdmsg_msg_result(msg, error);
 519                 }
 520         }
 521 }
 522
 523 static
 524 void
 525 disk_blk_freeblks(struct disk *dp, kdmsg_msg_t *msg)
 526 {
 527         struct dios_io *iost;
 528         struct buf *bp;
 529         struct bio *bio;
 530         int error = DMSG_ERR_NOSUPP;
 531         int reterr = 1;
 532
 533         /*
 534          * Only DMSG_BLK_FREEBLKS commands imply read ops.
 535          */
 536         iost = msg->state->any.any;
 537         if ((msg->any.head.cmd & DMSGF_CMDSWMASK) == DMSG_BLK_FREEBLKS) {
 538                 if (iost == NULL) {
 539                         iost = kmalloc(sizeof(*iost), M_DEVBUF,
 540                                        M_WAITOK | M_ZERO);
 541                         msg->state->any.any = iost;
 542                 }
 543                 reterr = 0;
 544                 bp = getpbuf(NULL);
 545                 bio = &bp->b_bio1;
 546                 bp->b_cmd = BUF_CMD_FREEBLKS;
 547                 bp->b_bcount = msg->any.blk_freeblks.bytes;
 548                 bp->b_resid = 0;
 549                 bio->bio_offset = msg->any.blk_freeblks.offset;
 550                 bio->bio_caller_info1.ptr = msg->state;
 551                 bio->bio_done = diskiodone;
 552
 553                 /* kdmsg_state_hold(msg->state); */
 554                 atomic_add_int(&blk_active, 1);
 555                 atomic_add_int(&iost->count, 1);
 556                 if (msg->any.head.cmd & DMSGF_DELETE)
 557                         iost->eof = 1;
 558                 BUF_KERNPROC(bp);
 559                 dev_dstrategy(dp->d_rawdev, bio);
 560         }
 561         if (reterr) {
 562                 if (msg->any.head.cmd & DMSGF_DELETE) {
 563                         if (iost && iost->count == 0) {
 564                                 kfree(iost, M_DEVBUF);
 565                                 msg->state->any.any = NULL;
 566                         }
 567                         kdmsg_msg_reply(msg, error);
 568                 } else {
 569                         kdmsg_msg_result(msg, error);
 570                 }
 571         }
 572 }
 573
 574 static
 575 void
 576 diskiodone(struct bio *bio)
 577 {
 578         struct buf *bp = bio->bio_buf;
 579         kdmsg_state_t *state = bio->bio_caller_info1.ptr;
 580         kdmsg_msg_t *rmsg;
 581         struct dios_io *iost = state->any.any;
 582         int error;
 583         int resid = 0;
 584         int bytes;
 585         uint32_t cmd;
 586         void *data;
 587
 588         cmd = DMSG_LNK_ERROR;
 589         data = NULL;
 590         bytes = 0;
 591
 592         switch(bp->b_cmd) {
 593         case BUF_CMD_READ:
 594                 cmd = DMSG_LNK_ERROR;
 595                 data = bp->b_data;
 596                 bytes = bp->b_bcount;
 597                 /* fall through */
 598         case BUF_CMD_WRITE:
 599                 if (bp->b_flags & B_ERROR) {
 600                         error = bp->b_error;
 601                 } else {
 602                         error = 0;
 603                         resid = bp->b_resid;
 604                 }
 605                 kdmsg_free_aux_data(&iost->data);
 606                 break;
 607         case BUF_CMD_FLUSH:
 608         case BUF_CMD_FREEBLKS:
 609                 if (bp->b_flags & B_ERROR)
 610                         error = bp->b_error;
 611                 else
 612                         error = 0;
 613                 break;
 614         default:
 615                 panic("diskiodone: Unknown bio cmd = %d\n",
 616                       bio->bio_buf->b_cmd);
 617                 error = 0;      /* avoid compiler warning */
 618                 break;          /* NOT REACHED */
 619         }
 620
 621         /*
 622          * Convert error to DMSG_ERR_* code.
 623          */
 624         if (error)
 625                 error = DMSG_ERR_IO;
 626
 627         /*
 628          * Convert LNK_ERROR or BLK_ERROR if non-zero resid.  READS will
 629          * have already converted cmd to BLK_ERROR and set up data to return.
 630          */
 631         if (resid && cmd == DMSG_LNK_ERROR)
 632                 cmd = DMSG_BLK_ERROR;
 633         /* XXX txcmd is delayed so this won't work for streaming */
 634         if ((state->txcmd & DMSGF_CREATE) == 0) /* assume serialized */
 635                 cmd |= DMSGF_CREATE;
 636         if (iost->eof) {
 637                 if (atomic_fetchadd_int(&iost->count, -1) == 1)
 638                         cmd |= DMSGF_DELETE;
 639         } else {
 640                 atomic_add_int(&iost->count, -1);
 641         }
 642         atomic_add_int(&blk_active, -1);
 643         cmd |= DMSGF_REPLY;
 644
 645         /*
 646          * Allocate a basic or extended reply.  Be careful not to populate
 647          * extended header fields unless we allocated an extended reply.
 648          */
 649         rmsg = kdmsg_msg_alloc(state, cmd, NULL, 0);
 650         if (data) {
 651                 rmsg->aux_data = kmalloc(bytes, state->iocom->mmsg, M_INTWAIT);
 652                 rmsg->aux_size = bytes;
 653                 rmsg->flags |= KDMSG_FLAG_AUXALLOC;
 654                 bcopy(data, rmsg->aux_data, bytes);
 655         }
 656         rmsg->any.blk_error.head.error = error;
 657         if ((cmd & DMSGF_BASECMDMASK) == DMSG_BLK_ERROR)
 658                 rmsg->any.blk_error.resid = resid;
 659         bio->bio_caller_info1.ptr = NULL;
 660         /* kdmsg_state_drop(state); */
 661         kdmsg_msg_write(rmsg);
 662         if (bp->b_flags & B_PAGING) {
 663                 relpbuf(bio->bio_buf, NULL);
 664         } else {
 665                 bp->b_flags |= B_INVAL | B_AGE;
 666                 brelse(bp);
 667         }
 668 }