cluster - xdisk automatic BIO restart
[dragonfly.git] / 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
56 #include <sys/dmsg.h>
57
58 #include <sys/buf2.h>
59 #include <sys/mplock2.h>
60 #include <sys/msgport2.h>
61 #include <sys/thread2.h>
62
63 struct dios_open {
64         int     openrd;
65         int     openwr;
66 };
67
68 struct dios_io {
69         int     count;
70         int     eof;
71 };
72
73 static MALLOC_DEFINE(M_DMSG_DISK, "dmsg_disk", "disk dmsg");
74
75 static int disk_iocom_reconnect(struct disk *dp, struct file *fp);
76 static int disk_rcvdmsg(kdmsg_msg_t *msg);
77
78 static void disk_blk_open(struct disk *dp, kdmsg_msg_t *msg);
79 static void disk_blk_read(struct disk *dp, kdmsg_msg_t *msg);
80 static void disk_blk_write(struct disk *dp, kdmsg_msg_t *msg);
81 static void disk_blk_flush(struct disk *dp, kdmsg_msg_t *msg);
82 static void disk_blk_freeblks(struct disk *dp, kdmsg_msg_t *msg);
83 static void diskiodone(struct bio *bio);
84
85 void
86 disk_iocom_init(struct disk *dp)
87 {
88         kdmsg_iocom_init(&dp->d_iocom, dp,
89                          KDMSG_IOCOMF_AUTOCONN |
90                          KDMSG_IOCOMF_AUTOSPAN |
91                          KDMSG_IOCOMF_AUTOCIRC,
92                          M_DMSG_DISK, disk_rcvdmsg);
93 }
94
95 void
96 disk_iocom_update(struct disk *dp)
97 {
98 }
99
100 void
101 disk_iocom_uninit(struct disk *dp)
102 {
103         kdmsg_iocom_uninit(&dp->d_iocom);
104 }
105
106 int
107 disk_iocom_ioctl(struct disk *dp, int cmd, void *data)
108 {
109         struct file *fp;
110         struct disk_ioc_recluster *recl;
111         int error;
112
113         switch(cmd) {
114         case DIOCRECLUSTER:
115                 recl = data;
116                 fp = holdfp(curproc->p_fd, recl->fd, -1);
117                 if (fp) {
118                         error = disk_iocom_reconnect(dp, fp);
119                 } else {
120                         error = EINVAL;
121                 }
122                 break;
123         default:
124                 error = EOPNOTSUPP;
125                 break;
126         }
127         return error;
128 }
129
130 static
131 int
132 disk_iocom_reconnect(struct disk *dp, struct file *fp)
133 {
134         char devname[64];
135
136         ksnprintf(devname, sizeof(devname), "%s%d",
137                   dev_dname(dp->d_rawdev), dkunit(dp->d_rawdev));
138
139         kdmsg_iocom_reconnect(&dp->d_iocom, fp, devname);
140
141         dp->d_iocom.auto_lnk_conn.pfs_type = DMSG_PFSTYPE_SERVER;
142         dp->d_iocom.auto_lnk_conn.proto_version = DMSG_SPAN_PROTO_1;
143         dp->d_iocom.auto_lnk_conn.peer_type = DMSG_PEER_BLOCK;
144         dp->d_iocom.auto_lnk_conn.peer_mask = 1LLU << DMSG_PEER_BLOCK;
145         dp->d_iocom.auto_lnk_conn.pfs_mask = (uint64_t)-1;
146         ksnprintf(dp->d_iocom.auto_lnk_conn.cl_label,
147                   sizeof(dp->d_iocom.auto_lnk_conn.cl_label),
148                   "%s/%s", hostname, devname);
149         if (dp->d_info.d_serialno) {
150                 ksnprintf(dp->d_iocom.auto_lnk_conn.fs_label,
151                           sizeof(dp->d_iocom.auto_lnk_conn.fs_label),
152                           "%s", dp->d_info.d_serialno);
153         }
154
155         dp->d_iocom.auto_lnk_span.pfs_type = DMSG_PFSTYPE_SERVER;
156         dp->d_iocom.auto_lnk_span.proto_version = DMSG_SPAN_PROTO_1;
157         dp->d_iocom.auto_lnk_span.peer_type = DMSG_PEER_BLOCK;
158         dp->d_iocom.auto_lnk_span.media.block.bytes =
159                                                 dp->d_info.d_media_size;
160         dp->d_iocom.auto_lnk_span.media.block.blksize =
161                                                 dp->d_info.d_media_blksize;
162         ksnprintf(dp->d_iocom.auto_lnk_span.cl_label,
163                   sizeof(dp->d_iocom.auto_lnk_span.cl_label),
164                   "%s/%s", hostname, devname);
165         if (dp->d_info.d_serialno) {
166                 ksnprintf(dp->d_iocom.auto_lnk_span.fs_label,
167                           sizeof(dp->d_iocom.auto_lnk_span.fs_label),
168                           "%s", dp->d_info.d_serialno);
169         }
170
171         kdmsg_iocom_autoinitiate(&dp->d_iocom, NULL);
172
173         return (0);
174 }
175
176 int
177 disk_rcvdmsg(kdmsg_msg_t *msg)
178 {
179         struct disk *dp = msg->iocom->handle;
180
181         /*
182          * Handle debug messages (these might not be in transactions)
183          */
184         switch(msg->any.head.cmd & DMSGF_CMDSWMASK) {
185         case DMSG_DBG_SHELL:
186                 /*
187                  * Execute shell command (not supported atm)
188                  */
189                 kdmsg_msg_reply(msg, DMSG_ERR_NOSUPP);
190                 return(0);
191         case DMSG_DBG_SHELL | DMSGF_REPLY:
192                 if (msg->aux_data) {
193                         msg->aux_data[msg->aux_size - 1] = 0;
194                         kprintf("diskiocom: DEBUGMSG: %s\n", msg->aux_data);
195                 }
196                 return(0);
197         }
198
199         /*
200          * All remaining messages must be in a transaction
201          *
202          * NOTE!  We are switching on the first message's command.  The
203          *        actual message command within the transaction may be
204          *        different (if streaming within a transaction).
205          */
206         if (msg->state == NULL) {
207                 kdmsg_msg_reply(msg, DMSG_ERR_NOSUPP);
208                 return(0);
209         }
210
211         switch(msg->state->rxcmd & DMSGF_CMDSWMASK) {
212         case DMSG_BLK_OPEN:
213         case DMSG_BLK_CLOSE:
214                 disk_blk_open(dp, msg);
215                 break;
216         case DMSG_BLK_READ:
217                 disk_blk_read(dp, msg);
218                 break;
219         case DMSG_BLK_WRITE:
220                 disk_blk_write(dp, msg);
221                 break;
222         case DMSG_BLK_FLUSH:
223                 disk_blk_flush(dp, msg);
224                 break;
225         case DMSG_BLK_FREEBLKS:
226                 disk_blk_freeblks(dp, msg);
227                 break;
228         default:
229                 if ((msg->any.head.cmd & DMSGF_REPLY) == 0) {
230                         if (msg->any.head.cmd & DMSGF_DELETE)
231                                 kdmsg_msg_reply(msg, DMSG_ERR_NOSUPP);
232                         else
233                                 kdmsg_msg_result(msg, DMSG_ERR_NOSUPP);
234                 }
235                 break;
236         }
237         return (0);
238 }
239
240 static
241 void
242 disk_blk_open(struct disk *dp, kdmsg_msg_t *msg)
243 {
244         struct dios_open *openst;
245         int error = DMSG_ERR_NOSUPP;
246         int fflags;
247
248         openst = msg->state->any.any;
249         if ((msg->any.head.cmd & DMSGF_CMDSWMASK) == DMSG_BLK_OPEN) {
250                 if (openst == NULL) {
251                         openst = kmalloc(sizeof(*openst), M_DEVBUF,
252                                                 M_WAITOK | M_ZERO);
253                         msg->state->any.any = openst;
254                 }
255                 fflags = 0;
256                 if (msg->any.blk_open.modes & DMSG_BLKOPEN_RD)
257                         fflags = FREAD;
258                 if (msg->any.blk_open.modes & DMSG_BLKOPEN_WR)
259                         fflags |= FWRITE;
260                 error = dev_dopen(dp->d_rawdev, fflags, S_IFCHR, proc0.p_ucred);
261                 if (error) {
262                         error = DMSG_ERR_IO;
263                 } else {
264                         if (msg->any.blk_open.modes & DMSG_BLKOPEN_RD)
265                                 ++openst->openrd;
266                         if (msg->any.blk_open.modes & DMSG_BLKOPEN_WR)
267                                 ++openst->openwr;
268                 }
269         }
270         if ((msg->any.head.cmd & DMSGF_CMDSWMASK) == DMSG_BLK_CLOSE &&
271             openst) {
272                 fflags = 0;
273                 if ((msg->any.blk_open.modes & DMSG_BLKOPEN_RD) &&
274                     openst->openrd) {
275                         fflags = FREAD;
276                 }
277                 if ((msg->any.blk_open.modes & DMSG_BLKOPEN_WR) &&
278                     openst->openwr) {
279                         fflags |= FWRITE;
280                 }
281                 error = dev_dclose(dp->d_rawdev, fflags, S_IFCHR);
282                 if (error) {
283                         error = DMSG_ERR_IO;
284                 } else {
285                         if (msg->any.blk_open.modes & DMSG_BLKOPEN_RD)
286                                 --openst->openrd;
287                         if (msg->any.blk_open.modes & DMSG_BLKOPEN_WR)
288                                 --openst->openwr;
289                 }
290         }
291         if (msg->any.head.cmd & DMSGF_DELETE) {
292                 if (openst) {
293                         while (openst->openrd && openst->openwr) {
294                                 --openst->openrd;
295                                 --openst->openwr;
296                                 dev_dclose(dp->d_rawdev, FREAD|FWRITE, S_IFCHR);
297                         }
298                         while (openst->openrd) {
299                                 --openst->openrd;
300                                 dev_dclose(dp->d_rawdev, FREAD, S_IFCHR);
301                         }
302                         while (openst->openwr) {
303                                 --openst->openwr;
304                                 dev_dclose(dp->d_rawdev, FWRITE, S_IFCHR);
305                         }
306                         kfree(openst, M_DEVBUF);
307                         msg->state->any.any = NULL;
308                 }
309                 kdmsg_msg_reply(msg, error);
310         } else {
311                 kdmsg_msg_result(msg, error);
312         }
313 }
314
315 static
316 void
317 disk_blk_read(struct disk *dp, kdmsg_msg_t *msg)
318 {
319         struct dios_io *iost;
320         struct buf *bp;
321         struct bio *bio;
322         int error = DMSG_ERR_NOSUPP;
323         int reterr = 1;
324
325         /*
326          * Only DMSG_BLK_READ commands imply read ops.
327          */
328         iost = msg->state->any.any;
329         if ((msg->any.head.cmd & DMSGF_CMDSWMASK) == DMSG_BLK_READ) {
330                 if (msg->any.blk_read.bytes < DEV_BSIZE ||
331                     msg->any.blk_read.bytes > MAXPHYS) {
332                         error = DMSG_ERR_PARAM;
333                         goto done;
334                 }
335                 if (iost == NULL) {
336                         iost = kmalloc(sizeof(*iost), M_DEVBUF,
337                                        M_WAITOK | M_ZERO);
338                         msg->state->any.any = iost;
339                 }
340                 reterr = 0;
341                 bp = geteblk(msg->any.blk_read.bytes);
342                 bio = &bp->b_bio1;
343                 bp->b_cmd = BUF_CMD_READ;
344                 bp->b_bcount = msg->any.blk_read.bytes;
345                 bp->b_resid = bp->b_bcount;
346                 bio->bio_offset = msg->any.blk_read.offset;
347                 bio->bio_caller_info1.ptr = msg->state;
348                 bio->bio_done = diskiodone;
349                 /* kdmsg_state_hold(msg->state); */
350
351                 atomic_add_int(&iost->count, 1);
352                 if (msg->any.head.cmd & DMSGF_DELETE)
353                         iost->eof = 1;
354                 BUF_KERNPROC(bp);
355                 dev_dstrategy(dp->d_rawdev, bio);
356         }
357 done:
358         if (reterr) {
359                 if (msg->any.head.cmd & DMSGF_DELETE) {
360                         if (iost && iost->count == 0) {
361                                 kfree(iost, M_DEVBUF);
362                                 msg->state->any.any = NULL;
363                         }
364                         kdmsg_msg_reply(msg, error);
365                 } else {
366                         kdmsg_msg_result(msg, error);
367                 }
368         }
369 }
370
371 static
372 void
373 disk_blk_write(struct disk *dp, kdmsg_msg_t *msg)
374 {
375         struct dios_io *iost;
376         struct buf *bp;
377         struct bio *bio;
378         int error = DMSG_ERR_NOSUPP;
379         int reterr = 1;
380
381         /*
382          * Only DMSG_BLK_WRITE commands imply read ops.
383          */
384         iost = msg->state->any.any;
385         if ((msg->any.head.cmd & DMSGF_CMDSWMASK) == DMSG_BLK_WRITE) {
386                 if (msg->any.blk_write.bytes < DEV_BSIZE ||
387                     msg->any.blk_write.bytes > MAXPHYS) {
388                         error = DMSG_ERR_PARAM;
389                         goto done;
390                 }
391                 if (iost == NULL) {
392                         iost = kmalloc(sizeof(*iost), M_DEVBUF,
393                                        M_WAITOK | M_ZERO);
394                         msg->state->any.any = iost;
395                 }
396
397                 /*
398                  * Issue WRITE.  Short data implies zeros.  Try to optimize
399                  * the buffer cache buffer for the case where we can just
400                  * use the message's data pointer.
401                  */
402                 reterr = 0;
403                 if (msg->aux_size >= msg->any.blk_write.bytes)
404                         bp = getpbuf(NULL);
405                 else
406                         bp = geteblk(msg->any.blk_write.bytes);
407                 bio = &bp->b_bio1;
408                 bp->b_cmd = BUF_CMD_WRITE;
409                 bp->b_bcount = msg->any.blk_write.bytes;
410                 bp->b_resid = bp->b_bcount;
411                 if (msg->aux_size >= msg->any.blk_write.bytes) {
412                         bp->b_data = msg->aux_data;
413                 } else {
414                         bcopy(msg->aux_data, bp->b_data, msg->aux_size);
415                         bzero(bp->b_data + msg->aux_size,
416                               msg->any.blk_write.bytes - msg->aux_size);
417                 }
418                 bio->bio_offset = msg->any.blk_write.offset;
419                 bio->bio_caller_info1.ptr = msg->state;
420                 bio->bio_done = diskiodone;
421                 /* kdmsg_state_hold(msg->state); */
422
423                 atomic_add_int(&iost->count, 1);
424                 if (msg->any.head.cmd & DMSGF_DELETE)
425                         iost->eof = 1;
426                 BUF_KERNPROC(bp);
427                 dev_dstrategy(dp->d_rawdev, bio);
428         }
429 done:
430         if (reterr) {
431                 if (msg->any.head.cmd & DMSGF_DELETE) {
432                         if (iost && iost->count == 0) {
433                                 kfree(iost, M_DEVBUF);
434                                 msg->state->any.any = NULL;
435                         }
436                         kdmsg_msg_reply(msg, error);
437                 } else {
438                         kdmsg_msg_result(msg, error);
439                 }
440         }
441 }
442
443 static
444 void
445 disk_blk_flush(struct disk *dp, kdmsg_msg_t *msg)
446 {
447         struct dios_io *iost;
448         struct buf *bp;
449         struct bio *bio;
450         int error = DMSG_ERR_NOSUPP;
451         int reterr = 1;
452
453         /*
454          * Only DMSG_BLK_FLUSH commands imply read ops.
455          */
456         iost = msg->state->any.any;
457         if ((msg->any.head.cmd & DMSGF_CMDSWMASK) == DMSG_BLK_FLUSH) {
458                 if (iost == NULL) {
459                         iost = kmalloc(sizeof(*iost), M_DEVBUF,
460                                        M_WAITOK | M_ZERO);
461                         msg->state->any.any = iost;
462                 }
463                 reterr = 0;
464                 bp = getpbuf(NULL);
465                 bio = &bp->b_bio1;
466                 bp->b_cmd = BUF_CMD_FLUSH;
467                 bp->b_bcount = msg->any.blk_flush.bytes;
468                 bp->b_resid = 0;
469                 bio->bio_offset = msg->any.blk_flush.offset;
470                 bio->bio_caller_info1.ptr = msg->state;
471                 bio->bio_done = diskiodone;
472                 /* kdmsg_state_hold(msg->state); */
473
474                 atomic_add_int(&iost->count, 1);
475                 if (msg->any.head.cmd & DMSGF_DELETE)
476                         iost->eof = 1;
477                 BUF_KERNPROC(bp);
478                 dev_dstrategy(dp->d_rawdev, bio);
479         }
480         if (reterr) {
481                 if (msg->any.head.cmd & DMSGF_DELETE) {
482                         if (iost && iost->count == 0) {
483                                 kfree(iost, M_DEVBUF);
484                                 msg->state->any.any = NULL;
485                         }
486                         kdmsg_msg_reply(msg, error);
487                 } else {
488                         kdmsg_msg_result(msg, error);
489                 }
490         }
491 }
492
493 static
494 void
495 disk_blk_freeblks(struct disk *dp, kdmsg_msg_t *msg)
496 {
497         struct dios_io *iost;
498         struct buf *bp;
499         struct bio *bio;
500         int error = DMSG_ERR_NOSUPP;
501         int reterr = 1;
502
503         /*
504          * Only DMSG_BLK_FREEBLKS commands imply read ops.
505          */
506         iost = msg->state->any.any;
507         if ((msg->any.head.cmd & DMSGF_CMDSWMASK) == DMSG_BLK_FREEBLKS) {
508                 if (iost == NULL) {
509                         iost = kmalloc(sizeof(*iost), M_DEVBUF,
510                                        M_WAITOK | M_ZERO);
511                         msg->state->any.any = iost;
512                 }
513                 reterr = 0;
514                 bp = getpbuf(NULL);
515                 bio = &bp->b_bio1;
516                 bp->b_cmd = BUF_CMD_FREEBLKS;
517                 bp->b_bcount = msg->any.blk_freeblks.bytes;
518                 bp->b_resid = 0;
519                 bio->bio_offset = msg->any.blk_freeblks.offset;
520                 bio->bio_caller_info1.ptr = msg->state;
521                 bio->bio_done = diskiodone;
522                 /* kdmsg_state_hold(msg->state); */
523
524                 atomic_add_int(&iost->count, 1);
525                 if (msg->any.head.cmd & DMSGF_DELETE)
526                         iost->eof = 1;
527                 BUF_KERNPROC(bp);
528                 dev_dstrategy(dp->d_rawdev, bio);
529         }
530         if (reterr) {
531                 if (msg->any.head.cmd & DMSGF_DELETE) {
532                         if (iost && iost->count == 0) {
533                                 kfree(iost, M_DEVBUF);
534                                 msg->state->any.any = NULL;
535                         }
536                         kdmsg_msg_reply(msg, error);
537                 } else {
538                         kdmsg_msg_result(msg, error);
539                 }
540         }
541 }
542
543 static
544 void
545 diskiodone(struct bio *bio)
546 {
547         struct buf *bp = bio->bio_buf;
548         kdmsg_state_t *state = bio->bio_caller_info1.ptr;
549         kdmsg_msg_t *rmsg;
550         struct dios_io *iost = state->any.any;
551         int error;
552         int resid = 0;
553         int bytes;
554         uint32_t cmd;
555         void *data;
556
557         cmd = DMSG_LNK_ERROR;
558         data = NULL;
559         bytes = 0;
560
561         switch(bp->b_cmd) {
562         case BUF_CMD_READ:
563                 cmd = DMSG_LNK_ERROR;
564                 data = bp->b_data;
565                 bytes = bp->b_bcount;
566                 /* fall through */
567         case BUF_CMD_WRITE:
568                 if (bp->b_flags & B_ERROR) {
569                         error = bp->b_error;
570                 } else {
571                         error = 0;
572                         resid = bp->b_resid;
573                 }
574                 break;
575         case BUF_CMD_FLUSH:
576         case BUF_CMD_FREEBLKS:
577                 if (bp->b_flags & B_ERROR)
578                         error = bp->b_error;
579                 else
580                         error = 0;
581                 break;
582         default:
583                 panic("diskiodone: Unknown bio cmd = %d\n",
584                       bio->bio_buf->b_cmd);
585                 error = 0;      /* avoid compiler warning */
586                 break;          /* NOT REACHED */
587         }
588
589         /*
590          * Convert error to DMSG_ERR_* code.
591          */
592         if (error)
593                 error = DMSG_ERR_IO;
594
595         /*
596          * Convert LNK_ERROR or BLK_ERROR if non-zero resid.  READS will
597          * have already converted cmd to BLK_ERROR and set up data to return.
598          */
599         if (resid && cmd == DMSG_LNK_ERROR)
600                 cmd = DMSG_BLK_ERROR;
601         /* XXX txcmd is delayed so this won't work for streaming */
602         if ((state->txcmd & DMSGF_CREATE) == 0) /* assume serialized */
603                 cmd |= DMSGF_CREATE;
604         if (iost->eof) {
605                 if (atomic_fetchadd_int(&iost->count, -1) == 1)
606                         cmd |= DMSGF_DELETE;
607         } else {
608                 atomic_add_int(&iost->count, -1);
609         }
610         cmd |= DMSGF_REPLY;
611
612         /*
613          * Allocate a basic or extended reply.  Be careful not to populate
614          * extended header fields unless we allocated an extended reply.
615          */
616         rmsg = kdmsg_msg_alloc_state(state, cmd, NULL, 0);
617         if (data) {
618                 rmsg->aux_data = kmalloc(bytes, state->iocom->mmsg, M_INTWAIT);
619                 rmsg->aux_size = bytes;
620                 rmsg->flags |= KDMSG_FLAG_AUXALLOC;
621                 bcopy(data, rmsg->aux_data, bytes);
622         }
623         rmsg->any.blk_error.head.error = error;
624         if ((cmd & DMSGF_BASECMDMASK) == DMSG_BLK_ERROR)
625                 rmsg->any.blk_error.resid = resid;
626         bio->bio_caller_info1.ptr = NULL;
627         /* kdmsg_state_drop(state); */
628         kdmsg_msg_write(rmsg);
629         if (bp->b_flags & B_PAGING) {
630                 relpbuf(bio->bio_buf, NULL);
631         } else {
632                 bp->b_flags |= B_INVAL | B_AGE;
633                 brelse(bp);
634         }
635 }