xref: /netbsd-src/sys/dev/dm/device-mapper.c (revision 3816d47b2c42fcd6e549e3407f842a5b1a1d23ad)
1 /*        $NetBSD: device-mapper.c,v 1.15 2010/01/08 00:27:48 pooka Exp $ */
2 
3 /*
4  * Copyright (c) 2008 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 #include <sys/module.h>
49 
50 #include "netbsd-dm.h"
51 #include "dm.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 int dmattach(void);
63 int dmdestroy(void);
64 
65 static int dm_cmd_to_fun(prop_dictionary_t);
66 static int disk_ioctl_switch(dev_t, u_long, void *);
67 static int dm_ioctl_switch(u_long);
68 static void dmminphys(struct buf *);
69 
70 /* CF attach/detach functions used for power management */
71 static int dm_detach(device_t, int);
72 static void dm_attach(device_t, device_t, void *);
73 static int dm_match(device_t, cfdata_t, void *);
74 
75 /* ***Variable-definitions*** */
76 const struct bdevsw dm_bdevsw = {
77 	.d_open = dmopen,
78 	.d_close = dmclose,
79 	.d_strategy = dmstrategy,
80 	.d_ioctl = dmioctl,
81 	.d_dump = nodump,
82 	.d_psize = dmsize,
83 	.d_flag = D_DISK | D_MPSAFE
84 };
85 
86 const struct cdevsw dm_cdevsw = {
87 	.d_open = dmopen,
88 	.d_close = dmclose,
89 	.d_read = dmread,
90 	.d_write = dmwrite,
91 	.d_ioctl = dmioctl,
92 	.d_stop = nostop,
93 	.d_tty = notty,
94 	.d_poll = nopoll,
95 	.d_mmap = nommap,
96 	.d_kqfilter = nokqfilter,
97 	.d_flag = D_DISK | D_MPSAFE
98 };
99 
100 const struct dkdriver dmdkdriver = {
101 	.d_strategy = dmstrategy
102 };
103 
104 #ifdef _MODULE
105 /* Autoconf defines */
106 CFDRIVER_DECL(dm, DV_DISK, NULL);
107 #endif
108 
109 CFATTACH_DECL3_NEW(dm, 0,
110      dm_match, dm_attach, dm_detach, NULL, NULL, NULL,
111      DVF_DETACH_SHUTDOWN);
112 
113 extern struct cfdriver dm_cd;
114 
115 extern uint64_t dev_counter;
116 
117 /*
118  * This array is used to translate cmd to function pointer.
119  *
120  * Interface between libdevmapper and lvm2tools uses different
121  * names for one IOCTL call because libdevmapper do another thing
122  * then. When I run "info" or "mknodes" libdevmapper will send same
123  * ioctl to kernel but will do another things in userspace.
124  *
125  */
126 struct cmd_function cmd_fn[] = {
127 		{ .cmd = "version", .fn = dm_get_version_ioctl},
128 		{ .cmd = "targets", .fn = dm_list_versions_ioctl},
129 		{ .cmd = "create",  .fn = dm_dev_create_ioctl},
130 		{ .cmd = "info",    .fn = dm_dev_status_ioctl},
131 		{ .cmd = "mknodes", .fn = dm_dev_status_ioctl},
132 		{ .cmd = "names",   .fn = dm_dev_list_ioctl},
133 		{ .cmd = "suspend", .fn = dm_dev_suspend_ioctl},
134 		{ .cmd = "remove",  .fn = dm_dev_remove_ioctl},
135 		{ .cmd = "rename",  .fn = dm_dev_rename_ioctl},
136 		{ .cmd = "resume",  .fn = dm_dev_resume_ioctl},
137 		{ .cmd = "clear",   .fn = dm_table_clear_ioctl},
138 		{ .cmd = "deps",    .fn = dm_table_deps_ioctl},
139 		{ .cmd = "reload",  .fn = dm_table_load_ioctl},
140 		{ .cmd = "status",  .fn = dm_table_status_ioctl},
141 		{ .cmd = "table",   .fn = dm_table_status_ioctl},
142 		{NULL, NULL}
143 };
144 
145 MODULE(MODULE_CLASS_DRIVER, dm, NULL);
146 
147 /* New module handle routine */
148 static int
149 dm_modcmd(modcmd_t cmd, void *arg)
150 {
151 #ifdef _MODULE
152 	int bmajor = -1, cmajor = -1;
153 	int error;
154 
155 	error = 0;
156 
157 	switch (cmd) {
158 	case MODULE_CMD_INIT:
159 		dmattach();
160 
161 		error = config_cfdriver_attach(&dm_cd);
162 		if (error)
163 			break;
164 
165 		error = config_cfattach_attach(dm_cd.cd_name, &dm_ca);
166 		if (error) {
167 			config_cfdriver_detach(&dm_cd);
168 			aprint_error("Unable to register cfattach for dm driver\n");
169 
170 			break;
171 		}
172 
173 		error =  devsw_attach("dm", &dm_bdevsw, &bmajor,
174 		    &dm_cdevsw, &cmajor);
175 		break;
176 
177 	case MODULE_CMD_FINI:
178 		/*
179 		 * Disable unloading of dm module if there are any devices
180 		 * defined in driver. This is probably too strong we need
181 		 * to disable auto-unload only if there is mounted dm device
182 		 * present.
183 		 */
184 		if (dev_counter > 0)
185 			return EBUSY;
186 		dmdestroy();
187 
188 		error = config_cfattach_detach(dm_cd.cd_name, &dm_ca);
189 		if (error)
190 			break;
191 
192 		config_cfdriver_detach(&dm_cd);
193 
194 		devsw_detach(&dm_bdevsw, &dm_cdevsw);
195 		break;
196 	case MODULE_CMD_STAT:
197 		return ENOTTY;
198 
199 	default:
200 		return ENOTTY;
201 	}
202 
203 	return error;
204 #else
205 
206 	if (cmd == MODULE_CMD_INIT)
207 		return 0;
208 	return ENOTTY;
209 
210 #endif /* _MODULE */
211 }
212 
213 
214 /*
215  * dm_match:
216  *
217  *	Autoconfiguration match function for pseudo-device glue.
218  */
219 static int
220 dm_match(device_t parent, cfdata_t match,
221     void *aux)
222 {
223 
224 	/* Pseudo-device; always present. */
225 	return (1);
226 }
227 
228 /*
229  * dm_attach:
230  *
231  *	Autoconfiguration attach function for pseudo-device glue.
232  */
233 static void
234 dm_attach(device_t parent, device_t self,
235     void *aux)
236 {
237 	return;
238 }
239 
240 
241 /*
242  * dm_detach:
243  *
244  *	Autoconfiguration detach function for pseudo-device glue.
245  * This routine is called by dm_ioctl::dm_dev_remove_ioctl and by autoconf to
246  * remove devices created in device-mapper.
247  */
248 static int
249 dm_detach(device_t self, int flags)
250 {
251 	dm_dev_t *dmv;
252 
253 	/* Detach device from global device list */
254 	if ((dmv = dm_dev_detach(self)) == NULL)
255 		return ENOENT;
256 
257 	/* Destroy active table first.  */
258 	dm_table_destroy(&dmv->table_head, DM_TABLE_ACTIVE);
259 
260 	/* Destroy inactive table if exits, too. */
261 	dm_table_destroy(&dmv->table_head, DM_TABLE_INACTIVE);
262 
263 	dm_table_head_destroy(&dmv->table_head);
264 
265 	/* Destroy disk device structure */
266 	disk_detach(dmv->diskp);
267 	disk_destroy(dmv->diskp);
268 
269 	/* Destroy device */
270 	(void)dm_dev_free(dmv);
271 
272 	/* Decrement device counter After removing device */
273 	atomic_dec_64(&dev_counter);
274 
275 	return 0;
276 }
277 
278 /* attach routine */
279 int
280 dmattach(void)
281 {
282 
283 	dm_target_init();
284 	dm_dev_init();
285 	dm_pdev_init();
286 
287 	return 0;
288 }
289 
290 /* Destroy routine */
291 int
292 dmdestroy(void)
293 {
294 
295 	dm_dev_destroy();
296 	dm_pdev_destroy();
297 	dm_target_destroy();
298 
299 	return 0;
300 }
301 
302 static int
303 dmopen(dev_t dev, int flags, int mode, struct lwp *l)
304 {
305 
306 	aprint_debug("dm open routine called %" PRIu32 "\n", minor(dev));
307 	return 0;
308 }
309 
310 static int
311 dmclose(dev_t dev, int flags, int mode, struct lwp *l)
312 {
313 
314 	aprint_debug("dm close routine called %" PRIu32 "\n", minor(dev));
315 	return 0;
316 }
317 
318 
319 static int
320 dmioctl(dev_t dev, const u_long cmd, void *data, int flag, struct lwp *l)
321 {
322 	int r;
323 	prop_dictionary_t dm_dict_in;
324 
325 	r = 0;
326 
327 	aprint_debug("dmioctl called\n");
328 
329 	KASSERT(data != NULL);
330 
331 	if (( r = disk_ioctl_switch(dev, cmd, data)) == ENOTTY) {
332 		struct plistref *pref = (struct plistref *) data;
333 
334 		/* Check if we were called with NETBSD_DM_IOCTL ioctl
335 		   otherwise quit. */
336 		if ((r = dm_ioctl_switch(cmd)) != 0)
337 			return r;
338 
339 		if((r = prop_dictionary_copyin_ioctl(pref, cmd, &dm_dict_in)) != 0)
340 			return r;
341 
342 		if ((r = dm_check_version(dm_dict_in)) != 0)
343 			goto cleanup_exit;
344 
345 		/* run ioctl routine */
346 		if ((r = dm_cmd_to_fun(dm_dict_in)) != 0)
347 			goto cleanup_exit;
348 
349 cleanup_exit:
350 		r = prop_dictionary_copyout_ioctl(pref, cmd, dm_dict_in);
351 		prop_object_release(dm_dict_in);
352 	}
353 
354 	return r;
355 }
356 
357 /*
358  * Translate command sent from libdevmapper to func.
359  */
360 static int
361 dm_cmd_to_fun(prop_dictionary_t dm_dict){
362 	int i, r;
363 	prop_string_t command;
364 
365 	r = 0;
366 
367 	if ((command = prop_dictionary_get(dm_dict, DM_IOCTL_COMMAND)) == NULL)
368 		return EINVAL;
369 
370 	for(i = 0; cmd_fn[i].cmd != NULL; i++)
371 		if (prop_string_equals_cstring(command, cmd_fn[i].cmd))
372 			break;
373 
374 	if (cmd_fn[i].cmd == NULL)
375 		return EINVAL;
376 
377 	aprint_debug("ioctl %s called\n", cmd_fn[i].cmd);
378 	r = cmd_fn[i].fn(dm_dict);
379 
380 	return r;
381 }
382 
383 /* Call apropriate ioctl handler function. */
384 static int
385 dm_ioctl_switch(u_long cmd)
386 {
387 
388 	switch(cmd) {
389 
390 	case NETBSD_DM_IOCTL:
391 		aprint_debug("dm NetBSD_DM_IOCTL called\n");
392 		break;
393 	default:
394 		 aprint_debug("dm unknown ioctl called\n");
395 		 return ENOTTY;
396 		 break; /* NOT REACHED */
397 	}
398 
399 	 return 0;
400 }
401 
402  /*
403   * Check for disk specific ioctls.
404   */
405 
406 static int
407 disk_ioctl_switch(dev_t dev, u_long cmd, void *data)
408 {
409 	dm_dev_t *dmv;
410 
411 	switch(cmd) {
412 	case DIOCGWEDGEINFO:
413 	{
414 		struct dkwedge_info *dkw = (void *) data;
415 
416 		if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL)
417 			return ENODEV;
418 
419 		aprint_debug("DIOCGWEDGEINFO ioctl called\n");
420 
421 		strlcpy(dkw->dkw_devname, dmv->name, 16);
422 		strlcpy(dkw->dkw_wname, dmv->name, DM_NAME_LEN);
423 		strlcpy(dkw->dkw_parent, dmv->name, 16);
424 
425 		dkw->dkw_offset = 0;
426 		dkw->dkw_size = dm_table_size(&dmv->table_head);
427 		strcpy(dkw->dkw_ptype, DKW_PTYPE_FFS);
428 
429 		dm_dev_unbusy(dmv);
430 		break;
431 	}
432 
433 	case DIOCGDISKINFO:
434 	{
435 		struct plistref *pref = (struct plistref *) data;
436 
437 		if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL)
438 			return ENODEV;
439 
440 		if (dmv->diskp->dk_info == NULL) {
441 			dm_dev_unbusy(dmv);
442 			return ENOTSUP;
443 		} else
444 			prop_dictionary_copyout_ioctl(pref, cmd,
445 			    dmv->diskp->dk_info);
446 
447 		dm_dev_unbusy(dmv);
448 		break;
449 	}
450 
451 	default:
452 		aprint_debug("unknown disk_ioctl called\n");
453 		return ENOTTY;
454 		break; /* NOT REACHED */
455 	}
456 
457 	return 0;
458 }
459 
460 /*
461  * Do all IO operations on dm logical devices.
462  */
463 static void
464 dmstrategy(struct buf *bp)
465 {
466 	dm_dev_t *dmv;
467 	dm_table_t  *tbl;
468 	dm_table_entry_t *table_en;
469 	struct buf *nestbuf;
470 
471 	uint32_t dev_type;
472 
473 	uint64_t buf_start, buf_len, issued_len;
474 	uint64_t table_start, table_end;
475 	uint64_t start, end;
476 
477 	buf_start = bp->b_blkno * DEV_BSIZE;
478 	buf_len = bp->b_bcount;
479 
480 	tbl = NULL;
481 
482 	table_end = 0;
483 	dev_type = 0;
484 	issued_len = 0;
485 
486 	if ((dmv = dm_dev_lookup(NULL, NULL, minor(bp->b_dev))) == NULL) {
487 		bp->b_error = EIO;
488 		bp->b_resid = bp->b_bcount;
489 		biodone(bp);
490 		return;
491 	}
492 
493 	if (bounds_check_with_mediasize(bp, DEV_BSIZE,
494 	    dm_table_size(&dmv->table_head)) <= 0) {
495 		dm_dev_unbusy(dmv);
496 		bp->b_resid = bp->b_bcount;
497 		biodone(bp);
498 		return;
499 	}
500 
501 	/*
502 	 * disk(9) is part of device structure and it can't be used without
503 	 * mutual exclusion, use diskp_mtx until it will be fixed.
504 	 */
505 	mutex_enter(&dmv->diskp_mtx);
506 	disk_busy(dmv->diskp);
507 	mutex_exit(&dmv->diskp_mtx);
508 
509 	/* Select active table */
510 	tbl = dm_table_get_entry(&dmv->table_head, DM_TABLE_ACTIVE);
511 
512 	 /* Nested buffers count down to zero therefore I have
513 	    to set bp->b_resid to maximal value. */
514 	bp->b_resid = bp->b_bcount;
515 
516 	/*
517 	 * Find out what tables I want to select.
518 	 */
519 	SLIST_FOREACH(table_en, tbl, next)
520 	{
521 		/* I need need number of bytes not blocks. */
522 		table_start = table_en->start * DEV_BSIZE;
523 		/*
524 		 * I have to sub 1 from table_en->length to prevent
525 		 * off by one error
526 		 */
527 		table_end = table_start + (table_en->length)* DEV_BSIZE;
528 
529 		start = MAX(table_start, buf_start);
530 
531 		end = MIN(table_end, buf_start + buf_len);
532 
533 		aprint_debug("----------------------------------------\n");
534 		aprint_debug("table_start %010" PRIu64", table_end %010"
535 		    PRIu64 "\n", table_start, table_end);
536 		aprint_debug("buf_start %010" PRIu64", buf_len %010"
537 		    PRIu64"\n", buf_start, buf_len);
538 		aprint_debug("start-buf_start %010"PRIu64", end %010"
539 		    PRIu64"\n", start - buf_start, end);
540 		aprint_debug("start %010" PRIu64" , end %010"
541                     PRIu64"\n", start, end);
542 		aprint_debug("\n----------------------------------------\n");
543 
544 		if (start < end) {
545 			/* create nested buffer  */
546 			nestbuf = getiobuf(NULL, true);
547 
548 			nestiobuf_setup(bp, nestbuf, start - buf_start,
549 			    (end - start));
550 
551 			issued_len += end - start;
552 
553 			/* I need number of blocks. */
554 			nestbuf->b_blkno = (start - table_start) / DEV_BSIZE;
555 
556 			table_en->target->strategy(table_en, nestbuf);
557 		}
558 	}
559 
560 	if (issued_len < buf_len)
561 		nestiobuf_done(bp, buf_len - issued_len, EINVAL);
562 
563 	mutex_enter(&dmv->diskp_mtx);
564 	disk_unbusy(dmv->diskp, buf_len, bp != NULL ? bp->b_flags & B_READ : 0);
565 	mutex_exit(&dmv->diskp_mtx);
566 
567 	dm_table_release(&dmv->table_head, DM_TABLE_ACTIVE);
568 	dm_dev_unbusy(dmv);
569 
570 	return;
571 }
572 
573 
574 static int
575 dmread(dev_t dev, struct uio *uio, int flag)
576 {
577 
578 	return (physio(dmstrategy, NULL, dev, B_READ, dmminphys, uio));
579 }
580 
581 static int
582 dmwrite(dev_t dev, struct uio *uio, int flag)
583 {
584 
585 	return (physio(dmstrategy, NULL, dev, B_WRITE, dmminphys, uio));
586 }
587 
588 static int
589 dmsize(dev_t dev)
590 {
591 	dm_dev_t *dmv;
592 	uint64_t size;
593 
594 	size = 0;
595 
596 	if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL)
597 			return -ENOENT;
598 
599 	size = dm_table_size(&dmv->table_head);
600 	dm_dev_unbusy(dmv);
601 
602   	return size;
603 }
604 
605 static void
606 dmminphys(struct buf *bp)
607 {
608 
609 	bp->b_bcount = MIN(bp->b_bcount, MAXPHYS);
610 }
611 
612 void
613 dmgetproperties(struct disk *disk, dm_table_head_t *head)
614 {
615 	prop_dictionary_t disk_info, odisk_info, geom;
616 	int dmp_size;
617 
618 	dmp_size = dm_table_size(head);
619 	disk_info = prop_dictionary_create();
620 	geom = prop_dictionary_create();
621 
622 	prop_dictionary_set_cstring_nocopy(disk_info, "type", "ESDI");
623 	prop_dictionary_set_uint64(geom, "sectors-per-unit", dmp_size);
624 	prop_dictionary_set_uint32(geom, "sector-size",
625 	    DEV_BSIZE /* XXX 512? */);
626 	prop_dictionary_set_uint32(geom, "sectors-per-track", 32);
627 	prop_dictionary_set_uint32(geom, "tracks-per-cylinder", 64);
628 	prop_dictionary_set_uint32(geom, "cylinders-per-unit", dmp_size / 2048);
629 	prop_dictionary_set(disk_info, "geometry", geom);
630 	prop_object_release(geom);
631 
632 	odisk_info = disk->dk_info;
633 	disk->dk_info = disk_info;
634 
635 	if (odisk_info != NULL)
636 		prop_object_release(odisk_info);
637 }
638