xref: /netbsd-src/sys/dev/dm/device-mapper.c (revision 97f8debd624665fdeaf9373bf4602036de3fcd85)
1 /*        $NetBSD: device-mapper.c,v 1.64 2022/03/31 19:30:15 pgoyette Exp $ */
2 
3 /*
4  * Copyright (c) 2010 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Adam Hamsik.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * I want to say thank you to all people who helped me with this project.
34  */
35 
36 #include <sys/types.h>
37 #include <sys/param.h>
38 #include <sys/buf.h>
39 #include <sys/conf.h>
40 #include <sys/device.h>
41 #include <sys/dkio.h>
42 #include <sys/disk.h>
43 #include <sys/disklabel.h>
44 #include <sys/ioctl.h>
45 #include <sys/ioccom.h>
46 #include <sys/kmem.h>
47 #include <sys/kauth.h>
48 
49 #include "netbsd-dm.h"
50 #include "dm.h"
51 #include "ioconf.h"
52 
53 static dev_type_open(dmopen);
54 static dev_type_close(dmclose);
55 static dev_type_read(dmread);
56 static dev_type_write(dmwrite);
57 static dev_type_ioctl(dmioctl);
58 static dev_type_strategy(dmstrategy);
59 static dev_type_size(dmsize);
60 
61 /* attach and detach routines */
62 #ifdef _MODULE
63 static int dmdestroy(void);
64 #endif
65 
66 static void dm_doinit(void);
67 
68 static int dm_cmd_to_fun(prop_dictionary_t);
69 static int disk_ioctl_switch(dev_t, unsigned long, void *);
70 static void dmminphys(struct buf *);
71 
72 /* CF attach/detach functions used for power management */
73 static int dm_detach(device_t, int);
74 static void dm_attach(device_t, device_t, void *);
75 static int dm_match(device_t, cfdata_t, void *);
76 
77 /* ***Variable-definitions*** */
78 const struct bdevsw dm_bdevsw = {
79 	.d_open = dmopen,
80 	.d_close = dmclose,
81 	.d_strategy = dmstrategy,
82 	.d_ioctl = dmioctl,
83 	.d_dump = nodump,
84 	.d_psize = dmsize,
85 	.d_discard = nodiscard,
86 	.d_flag = D_DISK | D_MPSAFE
87 };
88 
89 const struct cdevsw dm_cdevsw = {
90 	.d_open = dmopen,
91 	.d_close = dmclose,
92 	.d_read = dmread,
93 	.d_write = dmwrite,
94 	.d_ioctl = dmioctl,
95 	.d_stop = nostop,
96 	.d_tty = notty,
97 	.d_poll = nopoll,
98 	.d_mmap = nommap,
99 	.d_kqfilter = nokqfilter,
100 	.d_discard = nodiscard,
101 	.d_flag = D_DISK | D_MPSAFE
102 };
103 
104 const struct dkdriver dmdkdriver = {
105 	.d_strategy = dmstrategy
106 };
107 
108 CFATTACH_DECL3_NEW(dm, 0,
109      dm_match, dm_attach, dm_detach, NULL, NULL, NULL,
110      DVF_DETACH_SHUTDOWN);
111 
112 /*
113  * This structure is used to translate command sent to kernel driver in
114  * <key>command</key>
115  * <value></value>
116  * to function which I can call, and if the command is allowed for
117  * non-superusers.
118  */
119 /*
120  * This array is used to translate cmd to function pointer.
121  *
122  * Interface between libdevmapper and lvm2tools uses different
123  * names for one IOCTL call because libdevmapper do another thing
124  * then. When I run "info" or "mknodes" libdevmapper will send same
125  * ioctl to kernel but will do another things in userspace.
126  *
127  */
128 static const struct cmd_function {
129 	const char *cmd;
130 	int  (*fn)(prop_dictionary_t);
131 	int  allowed;
132 } cmd_fn[] = {
133 	{ .cmd = "version", .fn = NULL,                   .allowed = 1 },
134 	{ .cmd = "targets", .fn = dm_list_versions_ioctl, .allowed = 1 },
135 	{ .cmd = "create",  .fn = dm_dev_create_ioctl,    .allowed = 0 },
136 	{ .cmd = "info",    .fn = dm_dev_status_ioctl,    .allowed = 1 },
137 	{ .cmd = "mknodes", .fn = dm_dev_status_ioctl,    .allowed = 1 },
138 	{ .cmd = "names",   .fn = dm_dev_list_ioctl,      .allowed = 1 },
139 	{ .cmd = "suspend", .fn = dm_dev_suspend_ioctl,   .allowed = 0 },
140 	{ .cmd = "remove",  .fn = dm_dev_remove_ioctl,    .allowed = 0 },
141 	{ .cmd = "rename",  .fn = dm_dev_rename_ioctl,    .allowed = 0 },
142 	{ .cmd = "resume",  .fn = dm_dev_resume_ioctl,    .allowed = 0 },
143 	{ .cmd = "clear",   .fn = dm_table_clear_ioctl,   .allowed = 0 },
144 	{ .cmd = "deps",    .fn = dm_table_deps_ioctl,    .allowed = 1 },
145 	{ .cmd = "reload",  .fn = dm_table_load_ioctl,    .allowed = 0 },
146 	{ .cmd = "status",  .fn = dm_table_status_ioctl,  .allowed = 1 },
147 	{ .cmd = "table",   .fn = dm_table_status_ioctl,  .allowed = 1 },
148 	{ .cmd = NULL,      .fn = NULL,                   .allowed = 0 },
149 };
150 
151 #ifdef _MODULE
152 #include <sys/module.h>
153 
154 /* Autoconf defines */
155 CFDRIVER_DECL(dm, DV_DISK, NULL);
156 
157 MODULE(MODULE_CLASS_DRIVER, dm, "dk_subr");
158 
159 /* New module handle routine */
160 static int
dm_modcmd(modcmd_t cmd,void * arg)161 dm_modcmd(modcmd_t cmd, void *arg)
162 {
163 #ifdef _MODULE
164 	int error;
165 	devmajor_t bmajor, cmajor;
166 
167 	error = 0;
168 	bmajor = -1;
169 	cmajor = -1;
170 
171 	switch (cmd) {
172 	case MODULE_CMD_INIT:
173 		error = devsw_attach(dm_cd.cd_name, &dm_bdevsw, &bmajor,
174 		    &dm_cdevsw, &cmajor);
175 		if (error == EEXIST)
176 			error = 0;
177 		if (error)
178 			break;
179 
180 		error = config_cfdriver_attach(&dm_cd);
181 		if (error) {
182 			devsw_detach(&dm_bdevsw, &dm_cdevsw);
183 			return error;
184 		}
185 
186 		error = config_cfattach_attach(dm_cd.cd_name, &dm_ca);
187 		if (error) {
188 			config_cfdriver_detach(&dm_cd);
189 			devsw_detach(&dm_bdevsw, &dm_cdevsw);
190 			aprint_error("%s: unable to register cfattach\n",
191 			    dm_cd.cd_name);
192 			return error;
193 		}
194 
195 		dm_doinit();
196 		break;
197 	case MODULE_CMD_FINI:
198 		/*
199 		 * Disable unloading of dm module if there are any devices
200 		 * defined in driver. This is probably too strong we need
201 		 * to disable auto-unload only if there is mounted dm device
202 		 * present.
203 		 */
204 		if (dm_dev_counter > 0)
205 			return EBUSY;
206 		/* race window here */
207 
208 		error = dmdestroy();
209 		if (error)
210 			break;
211 
212 		config_cfdriver_detach(&dm_cd);
213 		config_cfattach_detach(dm_cd.cd_name, &dm_ca);
214 
215 		devsw_detach(&dm_bdevsw, &dm_cdevsw);
216 		break;
217 	case MODULE_CMD_STAT:
218 		return ENOTTY;
219 	default:
220 		return ENOTTY;
221 	}
222 
223 	return error;
224 #else
225 	return ENOTTY;
226 #endif
227 }
228 #endif /* _MODULE */
229 
230 /*
231  * dm_match:
232  *
233  *	Autoconfiguration match function for pseudo-device glue.
234  */
235 static int
dm_match(device_t parent,cfdata_t match,void * aux)236 dm_match(device_t parent, cfdata_t match, void *aux)
237 {
238 
239 	/* Pseudo-device; always present. */
240 	return 1;
241 }
242 
243 /*
244  * dm_attach:
245  *
246  *	Autoconfiguration attach function for pseudo-device glue.
247  */
248 static void
dm_attach(device_t parent,device_t self,void * aux)249 dm_attach(device_t parent, device_t self, void *aux)
250 {
251 
252 	if (!pmf_device_register(self, NULL, NULL))
253 		aprint_error_dev(self, "couldn't establish power handler\n");
254 }
255 
256 /*
257  * dm_detach:
258  *
259  *	Autoconfiguration detach function for pseudo-device glue.
260  * This routine is called by dm_ioctl::dm_dev_remove_ioctl and by autoconf to
261  * remove devices created in device-mapper.
262  */
263 static int
dm_detach(device_t self,int flags)264 dm_detach(device_t self, int flags)
265 {
266 	bool busy;
267 	dm_dev_t *dmv;
268 
269 	dmv = dm_dev_lookup(NULL, NULL, device_unit(self));
270 	mutex_enter(&dmv->diskp->dk_openlock);
271 	busy = (dmv->diskp->dk_openmask != 0 && (flags & DETACH_FORCE) == 0);
272 	mutex_exit(&dmv->diskp->dk_openlock);
273 	dm_dev_unbusy(dmv);
274 	if (busy)
275 		return EBUSY;
276 
277 	pmf_device_deregister(self);
278 
279 	/* Detach device from global device list */
280 	if ((dmv = dm_dev_detach(self)) == NULL)
281 		return ENOENT;
282 
283 	/* Destroy active table first.  */
284 	dm_table_destroy(&dmv->table_head, DM_TABLE_ACTIVE);
285 
286 	/* Destroy inactive table if exits, too. */
287 	dm_table_destroy(&dmv->table_head, DM_TABLE_INACTIVE);
288 
289 	dm_table_head_destroy(&dmv->table_head);
290 
291 	/* Destroy disk device structure */
292 	disk_detach(dmv->diskp);
293 	disk_destroy(dmv->diskp);
294 
295 	/* Destroy device */
296 	dm_dev_free(dmv);
297 
298 	/* Decrement device counter After removing device */
299 	atomic_dec_32(&dm_dev_counter);
300 
301 	return 0;
302 }
303 
304 static void
dm_doinit(void)305 dm_doinit(void)
306 {
307 
308 	dm_target_init();
309 	dm_dev_init();
310 	dm_pdev_init();
311 }
312 
313 /* attach routine */
314 void
dmattach(int n)315 dmattach(int n)
316 {
317 	int error;
318 
319 	error = config_cfattach_attach(dm_cd.cd_name, &dm_ca);
320 	if (error)
321 		aprint_error("%s: unable to register cfattach\n",
322 		    dm_cd.cd_name);
323 	else
324 		dm_doinit();
325 }
326 
327 #ifdef _MODULE
328 /* Destroy routine */
329 static int
dmdestroy(void)330 dmdestroy(void)
331 {
332 	int error;
333 
334 	error = config_cfattach_detach(dm_cd.cd_name, &dm_ca);
335 	if (error)
336 		return error;
337 
338 	dm_dev_destroy();
339 	dm_pdev_destroy();
340 	dm_target_destroy();
341 
342 	return 0;
343 }
344 #endif /* _MODULE */
345 
346 static int
dmopen(dev_t dev,int flags,int mode,struct lwp * l)347 dmopen(dev_t dev, int flags, int mode, struct lwp *l)
348 {
349 	dm_dev_t *dmv;
350 	struct disk *dk;
351 
352 	dmv = dm_dev_lookup(NULL, NULL, minor(dev));
353 	if (dmv) {
354 		dk = dmv->diskp;
355 		mutex_enter(&dk->dk_openlock);
356 		switch (mode) {
357 		case S_IFCHR:
358 			dk->dk_copenmask |= 1;
359 			break;
360 		case S_IFBLK:
361 			dk->dk_bopenmask |= 1;
362 			break;
363 		}
364 		dk->dk_openmask = dk->dk_copenmask | dk->dk_bopenmask;
365 		mutex_exit(&dk->dk_openlock);
366 		dm_dev_unbusy(dmv);
367 	}
368 
369 	aprint_debug("dm open routine called %" PRIu32 "\n", minor(dev));
370 	return 0;
371 }
372 
373 static int
dmclose(dev_t dev,int flags,int mode,struct lwp * l)374 dmclose(dev_t dev, int flags, int mode, struct lwp *l)
375 {
376 	dm_dev_t *dmv;
377 	struct disk *dk;
378 
379 	aprint_debug("dm close routine called %" PRIu32 "\n", minor(dev));
380 
381 	dmv = dm_dev_lookup(NULL, NULL, minor(dev));
382 	if (dmv) {
383 		dk = dmv->diskp;
384 		mutex_enter(&dk->dk_openlock);
385 		switch (mode) {
386 		case S_IFCHR:
387 			dk->dk_copenmask &= ~1;
388 			break;
389 		case S_IFBLK:
390 			dk->dk_bopenmask &= ~1;
391 			break;
392 		}
393 		dk->dk_openmask = dk->dk_copenmask | dk->dk_bopenmask;
394 		mutex_exit(&dk->dk_openlock);
395 		dm_dev_unbusy(dmv);
396 	}
397 	return 0;
398 }
399 
400 
401 static int
dmioctl(dev_t dev,const u_long cmd,void * data,int flag,struct lwp * l)402 dmioctl(dev_t dev, const u_long cmd, void *data, int flag, struct lwp *l)
403 {
404 	int r;
405 	prop_dictionary_t dm_dict_in;
406 
407 	aprint_debug("dmioctl called\n");
408 	KASSERT(data != NULL);
409 
410 	if ((r = disk_ioctl_switch(dev, cmd, data)) == ENOTTY) {
411 		struct plistref *pref = (struct plistref *)data;
412 
413 		switch(cmd) {
414 		case NETBSD_DM_IOCTL:
415 			aprint_debug("dm NETBSD_DM_IOCTL called\n");
416 			break;
417 		default:
418 			aprint_debug("dm unknown ioctl called\n");
419 			return ENOTTY;
420 			break; /* NOT REACHED */
421 		}
422 
423 		if ((r = prop_dictionary_copyin_ioctl(pref, cmd, &dm_dict_in))
424 		    != 0)
425 			return r;
426 
427 		if ((r = dm_check_version(dm_dict_in)) != 0)
428 			goto cleanup_exit;
429 
430 		/* run ioctl routine */
431 		if ((r = dm_cmd_to_fun(dm_dict_in)) != 0)
432 			goto cleanup_exit;
433 
434 cleanup_exit:
435 		r = prop_dictionary_copyout_ioctl(pref, cmd, dm_dict_in);
436 		prop_object_release(dm_dict_in);
437 	}
438 
439 	return r;
440 }
441 
442 /*
443  * Translate command sent from libdevmapper to func.
444  */
445 static int
dm_cmd_to_fun(prop_dictionary_t dm_dict)446 dm_cmd_to_fun(prop_dictionary_t dm_dict)
447 {
448 	int i, r;
449 	prop_string_t command;
450 
451 	if ((command = prop_dictionary_get(dm_dict, DM_IOCTL_COMMAND)) == NULL)
452 		return EINVAL;
453 
454 	for (i = 0; cmd_fn[i].cmd != NULL; i++)
455 		if (prop_string_equals_string(command, cmd_fn[i].cmd))
456 			break;
457 
458 	if (!cmd_fn[i].allowed &&
459 	    (r = kauth_authorize_system(kauth_cred_get(),
460 	    KAUTH_SYSTEM_DEVMAPPER, 0, NULL, NULL, NULL)) != 0)
461 		return r;
462 
463 	if (cmd_fn[i].cmd == NULL)
464 		return EINVAL;
465 
466 	aprint_debug("ioctl %s called %p\n", cmd_fn[i].cmd, cmd_fn[i].fn);
467 	if (cmd_fn[i].fn == NULL)
468 		return 0;
469 
470 	return cmd_fn[i].fn(dm_dict);
471 }
472 
473 /*
474  * Check for disk specific ioctls.
475  */
476 static int
disk_ioctl_switch(dev_t dev,unsigned long cmd,void * data)477 disk_ioctl_switch(dev_t dev, unsigned long cmd, void *data)
478 {
479 	dm_dev_t *dmv;
480 
481 	/* disk ioctls make sense only on block devices */
482 	if (minor(dev) == 0)
483 		return ENOTTY;
484 
485 	switch(cmd) {
486 	case DIOCGWEDGEINFO:
487 	{
488 		struct dkwedge_info *dkw = (void *) data;
489 
490 		if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL)
491 			return ENODEV;
492 
493 		aprint_debug("DIOCGWEDGEINFO ioctl called\n");
494 
495 		strlcpy(dkw->dkw_devname, dmv->name, 16);
496 		strlcpy(dkw->dkw_wname, dmv->name, DM_NAME_LEN);
497 		strlcpy(dkw->dkw_parent, dmv->name, 16);
498 
499 		dkw->dkw_offset = 0;
500 		dm_table_disksize(&dmv->table_head, &dkw->dkw_size, NULL);
501 		strcpy(dkw->dkw_ptype, DKW_PTYPE_FFS);
502 
503 		dm_dev_unbusy(dmv);
504 		break;
505 	}
506 	case DIOCGDISKINFO:
507 	{
508 		struct plistref *pref = (struct plistref *) data;
509 
510 		if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL)
511 			return ENODEV;
512 
513 		aprint_debug("DIOCGDISKINFO ioctl called\n");
514 
515 		if (dmv->diskp->dk_info == NULL) {
516 			dm_dev_unbusy(dmv);
517 			return ENOTSUP;
518 		} else
519 			prop_dictionary_copyout_ioctl(pref, cmd,
520 			    dmv->diskp->dk_info);
521 
522 		dm_dev_unbusy(dmv);
523 		break;
524 	}
525 	case DIOCCACHESYNC:
526 	{
527 		dm_table_entry_t *table_en;
528 		dm_table_t *tbl;
529 
530 		if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL)
531 			return ENODEV;
532 
533 		aprint_debug("DIOCCACHESYNC ioctl called\n");
534 
535 		/* Select active table */
536 		tbl = dm_table_get_entry(&dmv->table_head, DM_TABLE_ACTIVE);
537 
538 		/*
539 		 * Call sync target routine for all table entries. Target sync
540 		 * routine basically call DIOCCACHESYNC on underlying devices.
541 		 */
542 		SLIST_FOREACH(table_en, tbl, next)
543 			if (table_en->target->sync)
544 				table_en->target->sync(table_en);
545 		dm_table_release(&dmv->table_head, DM_TABLE_ACTIVE);
546 		dm_dev_unbusy(dmv);
547 		break;
548 	}
549 	case DIOCGSECTORSIZE:
550 	{
551 		unsigned int secsize, *valp = data;
552 
553 		if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL)
554 			return ENODEV;
555 
556 		aprint_debug("DIOCGSECTORSIZE ioctl called\n");
557 
558 		dm_table_disksize(&dmv->table_head, NULL, &secsize);
559 		*valp = secsize;
560 
561 		dm_dev_unbusy(dmv);
562 		break;
563 	}
564 	case DIOCGMEDIASIZE:
565 	{
566 		off_t *valp = data;
567 		uint64_t numsec;
568 		unsigned secsize;
569 
570 		if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL)
571 			return ENODEV;
572 
573 		aprint_debug("DIOCGMEDIASIZE ioctl called\n");
574 
575 		dm_table_disksize(&dmv->table_head, &numsec, &secsize);
576 		*valp = (off_t) secsize * numsec;
577 
578 		dm_dev_unbusy(dmv);
579 		break;
580 	}
581 	default:
582 		aprint_debug("unknown disk_ioctl called\n");
583 		return ENOTTY;
584 		break; /* NOT REACHED */
585 	}
586 
587 	return 0;
588 }
589 
590 /*
591  * Do all IO operations on dm logical devices.
592  */
593 static void
dmstrategy(struct buf * bp)594 dmstrategy(struct buf *bp)
595 {
596 	dm_dev_t *dmv;
597 	dm_table_t *tbl;
598 	dm_table_entry_t *table_en;
599 	struct buf *nestbuf;
600 
601 	uint64_t buf_start, buf_len, issued_len;
602 	uint64_t table_start, table_end;
603 	uint64_t start, end;
604 
605 	buf_start = bp->b_blkno * DEV_BSIZE;
606 	buf_len = bp->b_bcount;
607 
608 	table_end = 0;
609 	issued_len = 0;
610 
611 	if ((dmv = dm_dev_lookup(NULL, NULL, minor(bp->b_dev))) == NULL) {
612 		bp->b_error = EIO;
613 		bp->b_resid = bp->b_bcount;
614 		biodone(bp);
615 		return;
616 	}
617 
618 	if (bounds_check_with_mediasize(bp, DEV_BSIZE,
619 	    dm_table_size(&dmv->table_head)) <= 0) {
620 		dm_dev_unbusy(dmv);
621 		bp->b_resid = bp->b_bcount;
622 		biodone(bp);
623 		return;
624 	}
625 
626 	/*
627 	 * disk(9) is part of device structure and it can't be used without
628 	 * mutual exclusion, use diskp_mtx until it will be fixed.
629 	 */
630 	mutex_enter(&dmv->diskp_mtx);
631 	disk_busy(dmv->diskp);
632 	mutex_exit(&dmv->diskp_mtx);
633 
634 	/* Select active table */
635 	tbl = dm_table_get_entry(&dmv->table_head, DM_TABLE_ACTIVE);
636 
637 	 /* Nested buffers count down to zero therefore I have
638 	    to set bp->b_resid to maximal value. */
639 	bp->b_resid = bp->b_bcount;
640 
641 	/*
642 	 * Find out what tables I want to select.
643 	 */
644 	SLIST_FOREACH(table_en, tbl, next) {
645 		/* I need number of bytes not blocks. */
646 		table_start = table_en->start * DEV_BSIZE;
647 		/*
648 		 * I have to sub 1 from table_en->length to prevent
649 		 * off by one error
650 		 */
651 		table_end = table_start + table_en->length * DEV_BSIZE;
652 		start = MAX(table_start, buf_start);
653 		end = MIN(table_end, buf_start + buf_len);
654 
655 		aprint_debug("----------------------------------------\n");
656 		aprint_debug("table_start %010" PRIu64", table_end %010"
657 		    PRIu64 "\n", table_start, table_end);
658 		aprint_debug("buf_start %010" PRIu64", buf_len %010"
659 		    PRIu64"\n", buf_start, buf_len);
660 		aprint_debug("start-buf_start %010"PRIu64", end %010"
661 		    PRIu64"\n", start - buf_start, end);
662 		aprint_debug("start %010" PRIu64", end %010"
663                     PRIu64"\n", start, end);
664 		aprint_debug("----------------------------------------\n");
665 
666 		if (start < end) {
667 			/* create nested buffer  */
668 			nestbuf = getiobuf(NULL, true);
669 			nestiobuf_setup(bp, nestbuf, start - buf_start,
670 			    end - start);
671 			issued_len += end - start;
672 			/* I need number of blocks. */
673 			nestbuf->b_blkno = (start - table_start) / DEV_BSIZE;
674 			table_en->target->strategy(table_en, nestbuf);
675 		}
676 	}
677 
678 	if (issued_len < buf_len)
679 		nestiobuf_done(bp, buf_len - issued_len, EINVAL);
680 
681 	mutex_enter(&dmv->diskp_mtx);
682 	disk_unbusy(dmv->diskp, buf_len, bp ? (bp->b_flags & B_READ) : 0);
683 	mutex_exit(&dmv->diskp_mtx);
684 
685 	dm_table_release(&dmv->table_head, DM_TABLE_ACTIVE);
686 	dm_dev_unbusy(dmv);
687 }
688 
689 
690 static int
dmread(dev_t dev,struct uio * uio,int flag)691 dmread(dev_t dev, struct uio *uio, int flag)
692 {
693 
694 	return physio(dmstrategy, NULL, dev, B_READ, dmminphys, uio);
695 }
696 
697 static int
dmwrite(dev_t dev,struct uio * uio,int flag)698 dmwrite(dev_t dev, struct uio *uio, int flag)
699 {
700 
701 	return physio(dmstrategy, NULL, dev, B_WRITE, dmminphys, uio);
702 }
703 
704 static int
dmsize(dev_t dev)705 dmsize(dev_t dev)
706 {
707 	dm_dev_t *dmv;
708 	uint64_t size;
709 
710 	if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL)
711 		return -ENOENT;
712 
713 	size = dm_table_size(&dmv->table_head);
714 	dm_dev_unbusy(dmv);
715 
716 	return size;
717 }
718 
719 static void
dmminphys(struct buf * bp)720 dmminphys(struct buf *bp)
721 {
722 
723 	bp->b_bcount = MIN(bp->b_bcount, MAXPHYS);
724 }
725 
726 void
dmgetproperties(struct disk * disk,dm_table_head_t * head)727 dmgetproperties(struct disk *disk, dm_table_head_t *head)
728 {
729 	uint64_t numsec;
730 	unsigned int secsize;
731 	struct disk_geom *dg;
732 
733 	dm_table_disksize(head, &numsec, &secsize);
734 
735 	dg = &disk->dk_geom;
736 
737 	memset(dg, 0, sizeof(*dg));
738 	dg->dg_secperunit = numsec;
739 	dg->dg_secsize = secsize;
740 	dg->dg_nsectors = 32;
741 	dg->dg_ntracks = 64;
742 
743 	disk_set_info(NULL, disk, "ESDI");
744 }
745 
746 /*
747  * Transform char s to uint64_t offset number.
748  */
749 uint64_t
atoi64(const char * s)750 atoi64(const char *s)
751 {
752 	uint64_t n;
753 	n = 0;
754 
755 	while (*s != '\0') {
756 		if (!isdigit(*s))
757 			break;
758 
759 		n = (10 * n) + (*s - '0');
760 		s++;
761 	}
762 
763 	return n;
764 }
765