xref: /netbsd-src/sys/dev/dm/device-mapper.c (revision b1c86f5f087524e68db12794ee9c3e3da1ab17a0)
1 /*        $NetBSD: device-mapper.c,v 1.23 2010/05/18 15:10:38 haad 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 
39 #include <sys/buf.h>
40 #include <sys/conf.h>
41 #include <sys/device.h>
42 #include <sys/dkio.h>
43 #include <sys/disk.h>
44 #include <sys/disklabel.h>
45 #include <sys/ioctl.h>
46 #include <sys/ioccom.h>
47 #include <sys/kmem.h>
48 
49 #include "netbsd-dm.h"
50 #include "dm.h"
51 
52 static dev_type_open(dmopen);
53 static dev_type_close(dmclose);
54 static dev_type_read(dmread);
55 static dev_type_write(dmwrite);
56 static dev_type_ioctl(dmioctl);
57 static dev_type_strategy(dmstrategy);
58 static dev_type_size(dmsize);
59 
60 /* attach and detach routines */
61 void dmattach(int);
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, u_long, void *);
70 static int dm_ioctl_switch(u_long);
71 static void dmminphys(struct buf *);
72 
73 /* CF attach/detach functions used for power management */
74 static int dm_detach(device_t, int);
75 static void dm_attach(device_t, device_t, void *);
76 static int dm_match(device_t, cfdata_t, void *);
77 
78 /* ***Variable-definitions*** */
79 const struct bdevsw dm_bdevsw = {
80 	.d_open = dmopen,
81 	.d_close = dmclose,
82 	.d_strategy = dmstrategy,
83 	.d_ioctl = dmioctl,
84 	.d_dump = nodump,
85 	.d_psize = dmsize,
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_flag = D_DISK | D_MPSAFE
101 };
102 
103 const struct dkdriver dmdkdriver = {
104 	.d_strategy = dmstrategy
105 };
106 
107 CFATTACH_DECL3_NEW(dm, 0,
108      dm_match, dm_attach, dm_detach, NULL, NULL, NULL,
109      DVF_DETACH_SHUTDOWN);
110 
111 extern struct cfdriver dm_cd;
112 
113 extern uint64_t dm_dev_counter;
114 
115 /*
116  * This array is used to translate cmd to function pointer.
117  *
118  * Interface between libdevmapper and lvm2tools uses different
119  * names for one IOCTL call because libdevmapper do another thing
120  * then. When I run "info" or "mknodes" libdevmapper will send same
121  * ioctl to kernel but will do another things in userspace.
122  *
123  */
124 struct cmd_function cmd_fn[] = {
125 		{ .cmd = "version", .fn = dm_get_version_ioctl},
126 		{ .cmd = "targets", .fn = dm_list_versions_ioctl},
127 		{ .cmd = "create",  .fn = dm_dev_create_ioctl},
128 		{ .cmd = "info",    .fn = dm_dev_status_ioctl},
129 		{ .cmd = "mknodes", .fn = dm_dev_status_ioctl},
130 		{ .cmd = "names",   .fn = dm_dev_list_ioctl},
131 		{ .cmd = "suspend", .fn = dm_dev_suspend_ioctl},
132 		{ .cmd = "remove",  .fn = dm_dev_remove_ioctl},
133 		{ .cmd = "rename",  .fn = dm_dev_rename_ioctl},
134 		{ .cmd = "resume",  .fn = dm_dev_resume_ioctl},
135 		{ .cmd = "clear",   .fn = dm_table_clear_ioctl},
136 		{ .cmd = "deps",    .fn = dm_table_deps_ioctl},
137 		{ .cmd = "reload",  .fn = dm_table_load_ioctl},
138 		{ .cmd = "status",  .fn = dm_table_status_ioctl},
139 		{ .cmd = "table",   .fn = dm_table_status_ioctl},
140 		{NULL, NULL}
141 };
142 
143 #ifdef _MODULE
144 #include <sys/module.h>
145 
146 /* Autoconf defines */
147 CFDRIVER_DECL(dm, DV_DISK, NULL);
148 
149 MODULE(MODULE_CLASS_DRIVER, dm, NULL);
150 
151 /* New module handle routine */
152 static int
153 dm_modcmd(modcmd_t cmd, void *arg)
154 {
155 #ifdef _MODULE
156 	int error, bmajor, cmajor;
157 
158 	error = 0;
159 	bmajor = -1;
160 	cmajor = -1;
161 
162 	switch (cmd) {
163 	case MODULE_CMD_INIT:
164 		error = config_cfdriver_attach(&dm_cd);
165 		if (error)
166 			break;
167 
168 		error = config_cfattach_attach(dm_cd.cd_name, &dm_ca);
169 		if (error) {
170 			aprint_error("%s: unable to register cfattach\n",
171 			    dm_cd.cd_name);
172 			return error;
173 		}
174 
175 		error = devsw_attach(dm_cd.cd_name, &dm_bdevsw, &bmajor,
176 		    &dm_cdevsw, &cmajor);
177 		if (error) {
178 			config_cfattach_detach(dm_cd.cd_name, &dm_ca);
179 			config_cfdriver_detach(&dm_cd);
180 			break;
181 		}
182 
183 		dm_doinit();
184 
185 		break;
186 
187 	case MODULE_CMD_FINI:
188 		/*
189 		 * Disable unloading of dm module if there are any devices
190 		 * defined in driver. This is probably too strong we need
191 		 * to disable auto-unload only if there is mounted dm device
192 		 * present.
193 		 */
194 		if (dm_dev_counter > 0)
195 			return EBUSY;
196 
197 		error = dmdestroy();
198 		if (error)
199 			break;
200 
201 		config_cfdriver_detach(&dm_cd);
202 
203 		devsw_detach(&dm_bdevsw, &dm_cdevsw);
204 		break;
205 	case MODULE_CMD_STAT:
206 		return ENOTTY;
207 
208 	default:
209 		return ENOTTY;
210 	}
211 
212 	return error;
213 #else
214 	return ENOTTY;
215 #endif
216 }
217 #endif /* _MODULE */
218 
219 /*
220  * dm_match:
221  *
222  *	Autoconfiguration match function for pseudo-device glue.
223  */
224 static int
225 dm_match(device_t parent, cfdata_t match,
226     void *aux)
227 {
228 
229 	/* Pseudo-device; always present. */
230 	return (1);
231 }
232 
233 /*
234  * dm_attach:
235  *
236  *	Autoconfiguration attach function for pseudo-device glue.
237  */
238 static void
239 dm_attach(device_t parent, device_t self,
240     void *aux)
241 {
242 	return;
243 }
244 
245 
246 /*
247  * dm_detach:
248  *
249  *	Autoconfiguration detach function for pseudo-device glue.
250  * This routine is called by dm_ioctl::dm_dev_remove_ioctl and by autoconf to
251  * remove devices created in device-mapper.
252  */
253 static int
254 dm_detach(device_t self, int flags)
255 {
256 	dm_dev_t *dmv;
257 
258 	/* Detach device from global device list */
259 	if ((dmv = dm_dev_detach(self)) == NULL)
260 		return ENOENT;
261 
262 	/* Destroy active table first.  */
263 	dm_table_destroy(&dmv->table_head, DM_TABLE_ACTIVE);
264 
265 	/* Destroy inactive table if exits, too. */
266 	dm_table_destroy(&dmv->table_head, DM_TABLE_INACTIVE);
267 
268 	dm_table_head_destroy(&dmv->table_head);
269 
270 	/* Destroy disk device structure */
271 	disk_detach(dmv->diskp);
272 	disk_destroy(dmv->diskp);
273 
274 	/* Destroy device */
275 	(void)dm_dev_free(dmv);
276 
277 	/* Decrement device counter After removing device */
278 	atomic_dec_64(&dm_dev_counter);
279 
280 	return 0;
281 }
282 
283 static void
284 dm_doinit(void)
285 {
286 	dm_target_init();
287 	dm_dev_init();
288 	dm_pdev_init();
289 }
290 
291 /* attach routine */
292 void
293 dmattach(int n)
294 {
295 	int error;
296 
297 	error = config_cfattach_attach(dm_cd.cd_name, &dm_ca);
298 	if (error) {
299 		aprint_error("%s: unable to register cfattach\n",
300 		    dm_cd.cd_name);
301 	} else {
302 		dm_doinit();
303 	}
304 }
305 
306 #ifdef _MODULE
307 /* Destroy routine */
308 static int
309 dmdestroy(void)
310 {
311 	int error;
312 
313 	error = config_cfattach_detach(dm_cd.cd_name, &dm_ca);
314 	if (error)
315 		return error;
316 
317 	dm_dev_destroy();
318 	dm_pdev_destroy();
319 	dm_target_destroy();
320 
321 	return 0;
322 }
323 #endif /* _MODULE */
324 
325 static int
326 dmopen(dev_t dev, int flags, int mode, struct lwp *l)
327 {
328 
329 	aprint_debug("dm open routine called %" PRIu32 "\n", minor(dev));
330 	return 0;
331 }
332 
333 static int
334 dmclose(dev_t dev, int flags, int mode, struct lwp *l)
335 {
336 
337 	aprint_debug("dm close routine called %" PRIu32 "\n", minor(dev));
338 	return 0;
339 }
340 
341 
342 static int
343 dmioctl(dev_t dev, const u_long cmd, void *data, int flag, struct lwp *l)
344 {
345 	int r;
346 	prop_dictionary_t dm_dict_in;
347 
348 	r = 0;
349 
350 	aprint_debug("dmioctl called\n");
351 
352 	KASSERT(data != NULL);
353 
354 	if (( r = disk_ioctl_switch(dev, cmd, data)) == ENOTTY) {
355 		struct plistref *pref = (struct plistref *) data;
356 
357 		/* Check if we were called with NETBSD_DM_IOCTL ioctl
358 		   otherwise quit. */
359 		if ((r = dm_ioctl_switch(cmd)) != 0)
360 			return r;
361 
362 		if((r = prop_dictionary_copyin_ioctl(pref, cmd, &dm_dict_in)) != 0)
363 			return r;
364 
365 		if ((r = dm_check_version(dm_dict_in)) != 0)
366 			goto cleanup_exit;
367 
368 		/* run ioctl routine */
369 		if ((r = dm_cmd_to_fun(dm_dict_in)) != 0)
370 			goto cleanup_exit;
371 
372 cleanup_exit:
373 		r = prop_dictionary_copyout_ioctl(pref, cmd, dm_dict_in);
374 		prop_object_release(dm_dict_in);
375 	}
376 
377 	return r;
378 }
379 
380 /*
381  * Translate command sent from libdevmapper to func.
382  */
383 static int
384 dm_cmd_to_fun(prop_dictionary_t dm_dict){
385 	int i, r;
386 	prop_string_t command;
387 
388 	r = 0;
389 
390 	if ((command = prop_dictionary_get(dm_dict, DM_IOCTL_COMMAND)) == NULL)
391 		return EINVAL;
392 
393 	for(i = 0; cmd_fn[i].cmd != NULL; i++)
394 		if (prop_string_equals_cstring(command, cmd_fn[i].cmd))
395 			break;
396 
397 	if (cmd_fn[i].cmd == NULL)
398 		return EINVAL;
399 
400 	aprint_debug("ioctl %s called\n", cmd_fn[i].cmd);
401 	r = cmd_fn[i].fn(dm_dict);
402 
403 	return r;
404 }
405 
406 /* Call apropriate ioctl handler function. */
407 static int
408 dm_ioctl_switch(u_long cmd)
409 {
410 
411 	switch(cmd) {
412 
413 	case NETBSD_DM_IOCTL:
414 		aprint_debug("dm NetBSD_DM_IOCTL called\n");
415 		break;
416 	default:
417 		 aprint_debug("dm unknown ioctl called\n");
418 		 return ENOTTY;
419 		 break; /* NOT REACHED */
420 	}
421 
422 	 return 0;
423 }
424 
425  /*
426   * Check for disk specific ioctls.
427   */
428 
429 static int
430 disk_ioctl_switch(dev_t dev, u_long cmd, void *data)
431 {
432 	dm_dev_t *dmv;
433 
434 	/* disk ioctls make sense only on block devices */
435 	if (minor(dev) == 0)
436 		return ENOTTY;
437 
438 	switch(cmd) {
439 	case DIOCGWEDGEINFO:
440 	{
441 		struct dkwedge_info *dkw = (void *) data;
442 
443 		if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL)
444 			return ENODEV;
445 
446 		aprint_debug("DIOCGWEDGEINFO ioctl called\n");
447 
448 		strlcpy(dkw->dkw_devname, dmv->name, 16);
449 		strlcpy(dkw->dkw_wname, dmv->name, DM_NAME_LEN);
450 		strlcpy(dkw->dkw_parent, dmv->name, 16);
451 
452 		dkw->dkw_offset = 0;
453 		dkw->dkw_size = dm_table_size(&dmv->table_head);
454 		strcpy(dkw->dkw_ptype, DKW_PTYPE_FFS);
455 
456 		dm_dev_unbusy(dmv);
457 		break;
458 	}
459 
460 	case DIOCGDISKINFO:
461 	{
462 		struct plistref *pref = (struct plistref *) data;
463 
464 		if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL)
465 			return ENODEV;
466 
467 		if (dmv->diskp->dk_info == NULL) {
468 			dm_dev_unbusy(dmv);
469 			return ENOTSUP;
470 		} else
471 			prop_dictionary_copyout_ioctl(pref, cmd,
472 			    dmv->diskp->dk_info);
473 
474 		dm_dev_unbusy(dmv);
475 		break;
476 	}
477 
478 	case DIOCCACHESYNC:
479 	{
480 		dm_table_entry_t *table_en;
481 		dm_table_t *tbl;
482 		int err;
483 
484 		if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL)
485 			return ENODEV;
486 
487 		/* Select active table */
488 		tbl = dm_table_get_entry(&dmv->table_head, DM_TABLE_ACTIVE);
489 
490 		/*
491 		 * Call sync target routine for all table entries. Target sync
492 		 * routine basically call DIOCCACHESYNC on underlying devices.
493 		 */
494 		SLIST_FOREACH(table_en, tbl, next)
495 		{
496 			err = table_en->target->sync(table_en);
497 		}
498 		dm_table_release(&dmv->table_head, DM_TABLE_ACTIVE);
499 		dm_dev_unbusy(dmv);
500 		break;
501 	}
502 
503 
504 	default:
505 		aprint_debug("unknown disk_ioctl called\n");
506 		return ENOTTY;
507 		break; /* NOT REACHED */
508 	}
509 
510 	return 0;
511 }
512 
513 /*
514  * Do all IO operations on dm logical devices.
515  */
516 static void
517 dmstrategy(struct buf *bp)
518 {
519 	dm_dev_t *dmv;
520 	dm_table_t  *tbl;
521 	dm_table_entry_t *table_en;
522 	struct buf *nestbuf;
523 
524 	uint32_t dev_type;
525 
526 	uint64_t buf_start, buf_len, issued_len;
527 	uint64_t table_start, table_end;
528 	uint64_t start, end;
529 
530 	buf_start = bp->b_blkno * DEV_BSIZE;
531 	buf_len = bp->b_bcount;
532 
533 	tbl = NULL;
534 
535 	table_end = 0;
536 	dev_type = 0;
537 	issued_len = 0;
538 
539 	if ((dmv = dm_dev_lookup(NULL, NULL, minor(bp->b_dev))) == NULL) {
540 		bp->b_error = EIO;
541 		bp->b_resid = bp->b_bcount;
542 		biodone(bp);
543 		return;
544 	}
545 
546 	if (bounds_check_with_mediasize(bp, DEV_BSIZE,
547 	    dm_table_size(&dmv->table_head)) <= 0) {
548 		dm_dev_unbusy(dmv);
549 		bp->b_resid = bp->b_bcount;
550 		biodone(bp);
551 		return;
552 	}
553 
554 	/*
555 	 * disk(9) is part of device structure and it can't be used without
556 	 * mutual exclusion, use diskp_mtx until it will be fixed.
557 	 */
558 	mutex_enter(&dmv->diskp_mtx);
559 	disk_busy(dmv->diskp);
560 	mutex_exit(&dmv->diskp_mtx);
561 
562 	/* Select active table */
563 	tbl = dm_table_get_entry(&dmv->table_head, DM_TABLE_ACTIVE);
564 
565 	 /* Nested buffers count down to zero therefore I have
566 	    to set bp->b_resid to maximal value. */
567 	bp->b_resid = bp->b_bcount;
568 
569 	/*
570 	 * Find out what tables I want to select.
571 	 */
572 	SLIST_FOREACH(table_en, tbl, next)
573 	{
574 		/* I need need number of bytes not blocks. */
575 		table_start = table_en->start * DEV_BSIZE;
576 		/*
577 		 * I have to sub 1 from table_en->length to prevent
578 		 * off by one error
579 		 */
580 		table_end = table_start + (table_en->length)* DEV_BSIZE;
581 
582 		start = MAX(table_start, buf_start);
583 
584 		end = MIN(table_end, buf_start + buf_len);
585 
586 		aprint_debug("----------------------------------------\n");
587 		aprint_debug("table_start %010" PRIu64", table_end %010"
588 		    PRIu64 "\n", table_start, table_end);
589 		aprint_debug("buf_start %010" PRIu64", buf_len %010"
590 		    PRIu64"\n", buf_start, buf_len);
591 		aprint_debug("start-buf_start %010"PRIu64", end %010"
592 		    PRIu64"\n", start - buf_start, end);
593 		aprint_debug("start %010" PRIu64" , end %010"
594                     PRIu64"\n", start, end);
595 		aprint_debug("\n----------------------------------------\n");
596 
597 		if (start < end) {
598 			/* create nested buffer  */
599 			nestbuf = getiobuf(NULL, true);
600 
601 			nestiobuf_setup(bp, nestbuf, start - buf_start,
602 			    (end - start));
603 
604 			issued_len += end - start;
605 
606 			/* I need number of blocks. */
607 			nestbuf->b_blkno = (start - table_start) / DEV_BSIZE;
608 
609 			table_en->target->strategy(table_en, nestbuf);
610 		}
611 	}
612 
613 	if (issued_len < buf_len)
614 		nestiobuf_done(bp, buf_len - issued_len, EINVAL);
615 
616 	mutex_enter(&dmv->diskp_mtx);
617 	disk_unbusy(dmv->diskp, buf_len, bp != NULL ? bp->b_flags & B_READ : 0);
618 	mutex_exit(&dmv->diskp_mtx);
619 
620 	dm_table_release(&dmv->table_head, DM_TABLE_ACTIVE);
621 	dm_dev_unbusy(dmv);
622 
623 	return;
624 }
625 
626 
627 static int
628 dmread(dev_t dev, struct uio *uio, int flag)
629 {
630 
631 	return (physio(dmstrategy, NULL, dev, B_READ, dmminphys, uio));
632 }
633 
634 static int
635 dmwrite(dev_t dev, struct uio *uio, int flag)
636 {
637 
638 	return (physio(dmstrategy, NULL, dev, B_WRITE, dmminphys, uio));
639 }
640 
641 static int
642 dmsize(dev_t dev)
643 {
644 	dm_dev_t *dmv;
645 	uint64_t size;
646 
647 	size = 0;
648 
649 	if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL)
650 			return -ENOENT;
651 
652 	size = dm_table_size(&dmv->table_head);
653 	dm_dev_unbusy(dmv);
654 
655   	return size;
656 }
657 
658 static void
659 dmminphys(struct buf *bp)
660 {
661 
662 	bp->b_bcount = MIN(bp->b_bcount, MAXPHYS);
663 }
664 
665 void
666 dmgetproperties(struct disk *disk, dm_table_head_t *head)
667 {
668 	prop_dictionary_t disk_info, odisk_info, geom;
669 	int dmp_size;
670 
671 	dmp_size = dm_table_size(head);
672 	disk_info = prop_dictionary_create();
673 	geom = prop_dictionary_create();
674 
675 	prop_dictionary_set_cstring_nocopy(disk_info, "type", "ESDI");
676 	prop_dictionary_set_uint64(geom, "sectors-per-unit", dmp_size);
677 	prop_dictionary_set_uint32(geom, "sector-size",
678 	    DEV_BSIZE /* XXX 512? */);
679 	prop_dictionary_set_uint32(geom, "sectors-per-track", 32);
680 	prop_dictionary_set_uint32(geom, "tracks-per-cylinder", 64);
681 	prop_dictionary_set_uint32(geom, "cylinders-per-unit", dmp_size / 2048);
682 	prop_dictionary_set(disk_info, "geometry", geom);
683 	prop_object_release(geom);
684 
685 	odisk_info = disk->dk_info;
686 	disk->dk_info = disk_info;
687 
688 	if (odisk_info != NULL)
689 		prop_object_release(odisk_info);
690 }
691