1 /*
2  * Copyright (C) 2001 Sistina Software (UK) Limited.
3  * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
4  *
5  * This file is released under the GPL.
6  */
7 
8 #include "dm-core.h"
9 #include "dm-rq.h"
10 
11 #include <linux/module.h>
12 #include <linux/vmalloc.h>
13 #include <linux/blkdev.h>
14 #include <linux/blk-integrity.h>
15 #include <linux/namei.h>
16 #include <linux/ctype.h>
17 #include <linux/string.h>
18 #include <linux/slab.h>
19 #include <linux/interrupt.h>
20 #include <linux/mutex.h>
21 #include <linux/delay.h>
22 #include <linux/atomic.h>
23 #include <linux/blk-mq.h>
24 #include <linux/mount.h>
25 #include <linux/dax.h>
26 
27 #define DM_MSG_PREFIX "table"
28 
29 #define NODE_SIZE L1_CACHE_BYTES
30 #define KEYS_PER_NODE (NODE_SIZE / sizeof(sector_t))
31 #define CHILDREN_PER_NODE (KEYS_PER_NODE + 1)
32 
33 /*
34  * Similar to ceiling(log_size(n))
35  */
int_log(unsigned int n,unsigned int base)36 static unsigned int int_log(unsigned int n, unsigned int base)
37 {
38 	int result = 0;
39 
40 	while (n > 1) {
41 		n = dm_div_up(n, base);
42 		result++;
43 	}
44 
45 	return result;
46 }
47 
48 /*
49  * Calculate the index of the child node of the n'th node k'th key.
50  */
get_child(unsigned int n,unsigned int k)51 static inline unsigned int get_child(unsigned int n, unsigned int k)
52 {
53 	return (n * CHILDREN_PER_NODE) + k;
54 }
55 
56 /*
57  * Return the n'th node of level l from table t.
58  */
get_node(struct dm_table * t,unsigned int l,unsigned int n)59 static inline sector_t *get_node(struct dm_table *t,
60 				 unsigned int l, unsigned int n)
61 {
62 	return t->index[l] + (n * KEYS_PER_NODE);
63 }
64 
65 /*
66  * Return the highest key that you could lookup from the n'th
67  * node on level l of the btree.
68  */
high(struct dm_table * t,unsigned int l,unsigned int n)69 static sector_t high(struct dm_table *t, unsigned int l, unsigned int n)
70 {
71 	for (; l < t->depth - 1; l++)
72 		n = get_child(n, CHILDREN_PER_NODE - 1);
73 
74 	if (n >= t->counts[l])
75 		return (sector_t) - 1;
76 
77 	return get_node(t, l, n)[KEYS_PER_NODE - 1];
78 }
79 
80 /*
81  * Fills in a level of the btree based on the highs of the level
82  * below it.
83  */
setup_btree_index(unsigned int l,struct dm_table * t)84 static int setup_btree_index(unsigned int l, struct dm_table *t)
85 {
86 	unsigned int n, k;
87 	sector_t *node;
88 
89 	for (n = 0U; n < t->counts[l]; n++) {
90 		node = get_node(t, l, n);
91 
92 		for (k = 0U; k < KEYS_PER_NODE; k++)
93 			node[k] = high(t, l + 1, get_child(n, k));
94 	}
95 
96 	return 0;
97 }
98 
99 /*
100  * highs, and targets are managed as dynamic arrays during a
101  * table load.
102  */
alloc_targets(struct dm_table * t,unsigned int num)103 static int alloc_targets(struct dm_table *t, unsigned int num)
104 {
105 	sector_t *n_highs;
106 	struct dm_target *n_targets;
107 
108 	/*
109 	 * Allocate both the target array and offset array at once.
110 	 */
111 	n_highs = kvcalloc(num, sizeof(struct dm_target) + sizeof(sector_t),
112 			   GFP_KERNEL);
113 	if (!n_highs)
114 		return -ENOMEM;
115 
116 	n_targets = (struct dm_target *) (n_highs + num);
117 
118 	memset(n_highs, -1, sizeof(*n_highs) * num);
119 	kvfree(t->highs);
120 
121 	t->num_allocated = num;
122 	t->highs = n_highs;
123 	t->targets = n_targets;
124 
125 	return 0;
126 }
127 
dm_table_create(struct dm_table ** result,fmode_t mode,unsigned num_targets,struct mapped_device * md)128 int dm_table_create(struct dm_table **result, fmode_t mode,
129 		    unsigned num_targets, struct mapped_device *md)
130 {
131 	struct dm_table *t = kzalloc(sizeof(*t), GFP_KERNEL);
132 
133 	if (!t)
134 		return -ENOMEM;
135 
136 	INIT_LIST_HEAD(&t->devices);
137 
138 	if (!num_targets)
139 		num_targets = KEYS_PER_NODE;
140 
141 	num_targets = dm_round_up(num_targets, KEYS_PER_NODE);
142 
143 	if (!num_targets) {
144 		kfree(t);
145 		return -ENOMEM;
146 	}
147 
148 	if (alloc_targets(t, num_targets)) {
149 		kfree(t);
150 		return -ENOMEM;
151 	}
152 
153 	t->type = DM_TYPE_NONE;
154 	t->mode = mode;
155 	t->md = md;
156 	*result = t;
157 	return 0;
158 }
159 
free_devices(struct list_head * devices,struct mapped_device * md)160 static void free_devices(struct list_head *devices, struct mapped_device *md)
161 {
162 	struct list_head *tmp, *next;
163 
164 	list_for_each_safe(tmp, next, devices) {
165 		struct dm_dev_internal *dd =
166 		    list_entry(tmp, struct dm_dev_internal, list);
167 		DMWARN("%s: dm_table_destroy: dm_put_device call missing for %s",
168 		       dm_device_name(md), dd->dm_dev->name);
169 		dm_put_table_device(md, dd->dm_dev);
170 		kfree(dd);
171 	}
172 }
173 
174 static void dm_table_destroy_crypto_profile(struct dm_table *t);
175 
dm_table_destroy(struct dm_table * t)176 void dm_table_destroy(struct dm_table *t)
177 {
178 	if (!t)
179 		return;
180 
181 	/* free the indexes */
182 	if (t->depth >= 2)
183 		kvfree(t->index[t->depth - 2]);
184 
185 	/* free the targets */
186 	for (unsigned int i = 0; i < t->num_targets; i++) {
187 		struct dm_target *ti = dm_table_get_target(t, i);
188 
189 		if (ti->type->dtr)
190 			ti->type->dtr(ti);
191 
192 		dm_put_target_type(ti->type);
193 	}
194 
195 	kvfree(t->highs);
196 
197 	/* free the device list */
198 	free_devices(&t->devices, t->md);
199 
200 	dm_free_md_mempools(t->mempools);
201 
202 	dm_table_destroy_crypto_profile(t);
203 
204 	kfree(t);
205 }
206 
207 /*
208  * See if we've already got a device in the list.
209  */
find_device(struct list_head * l,dev_t dev)210 static struct dm_dev_internal *find_device(struct list_head *l, dev_t dev)
211 {
212 	struct dm_dev_internal *dd;
213 
214 	list_for_each_entry (dd, l, list)
215 		if (dd->dm_dev->bdev->bd_dev == dev)
216 			return dd;
217 
218 	return NULL;
219 }
220 
221 /*
222  * If possible, this checks an area of a destination device is invalid.
223  */
device_area_is_invalid(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)224 static int device_area_is_invalid(struct dm_target *ti, struct dm_dev *dev,
225 				  sector_t start, sector_t len, void *data)
226 {
227 	struct queue_limits *limits = data;
228 	struct block_device *bdev = dev->bdev;
229 	sector_t dev_size = bdev_nr_sectors(bdev);
230 	unsigned short logical_block_size_sectors =
231 		limits->logical_block_size >> SECTOR_SHIFT;
232 
233 	if (!dev_size)
234 		return 0;
235 
236 	if ((start >= dev_size) || (start + len > dev_size)) {
237 		DMERR("%s: %pg too small for target: "
238 		      "start=%llu, len=%llu, dev_size=%llu",
239 		      dm_device_name(ti->table->md), bdev,
240 		      (unsigned long long)start,
241 		      (unsigned long long)len,
242 		      (unsigned long long)dev_size);
243 		return 1;
244 	}
245 
246 	/*
247 	 * If the target is mapped to zoned block device(s), check
248 	 * that the zones are not partially mapped.
249 	 */
250 	if (bdev_is_zoned(bdev)) {
251 		unsigned int zone_sectors = bdev_zone_sectors(bdev);
252 
253 		if (start & (zone_sectors - 1)) {
254 			DMERR("%s: start=%llu not aligned to h/w zone size %u of %pg",
255 			      dm_device_name(ti->table->md),
256 			      (unsigned long long)start,
257 			      zone_sectors, bdev);
258 			return 1;
259 		}
260 
261 		/*
262 		 * Note: The last zone of a zoned block device may be smaller
263 		 * than other zones. So for a target mapping the end of a
264 		 * zoned block device with such a zone, len would not be zone
265 		 * aligned. We do not allow such last smaller zone to be part
266 		 * of the mapping here to ensure that mappings with multiple
267 		 * devices do not end up with a smaller zone in the middle of
268 		 * the sector range.
269 		 */
270 		if (len & (zone_sectors - 1)) {
271 			DMERR("%s: len=%llu not aligned to h/w zone size %u of %pg",
272 			      dm_device_name(ti->table->md),
273 			      (unsigned long long)len,
274 			      zone_sectors, bdev);
275 			return 1;
276 		}
277 	}
278 
279 	if (logical_block_size_sectors <= 1)
280 		return 0;
281 
282 	if (start & (logical_block_size_sectors - 1)) {
283 		DMERR("%s: start=%llu not aligned to h/w "
284 		      "logical block size %u of %pg",
285 		      dm_device_name(ti->table->md),
286 		      (unsigned long long)start,
287 		      limits->logical_block_size, bdev);
288 		return 1;
289 	}
290 
291 	if (len & (logical_block_size_sectors - 1)) {
292 		DMERR("%s: len=%llu not aligned to h/w "
293 		      "logical block size %u of %pg",
294 		      dm_device_name(ti->table->md),
295 		      (unsigned long long)len,
296 		      limits->logical_block_size, bdev);
297 		return 1;
298 	}
299 
300 	return 0;
301 }
302 
303 /*
304  * This upgrades the mode on an already open dm_dev, being
305  * careful to leave things as they were if we fail to reopen the
306  * device and not to touch the existing bdev field in case
307  * it is accessed concurrently.
308  */
upgrade_mode(struct dm_dev_internal * dd,fmode_t new_mode,struct mapped_device * md)309 static int upgrade_mode(struct dm_dev_internal *dd, fmode_t new_mode,
310 			struct mapped_device *md)
311 {
312 	int r;
313 	struct dm_dev *old_dev, *new_dev;
314 
315 	old_dev = dd->dm_dev;
316 
317 	r = dm_get_table_device(md, dd->dm_dev->bdev->bd_dev,
318 				dd->dm_dev->mode | new_mode, &new_dev);
319 	if (r)
320 		return r;
321 
322 	dd->dm_dev = new_dev;
323 	dm_put_table_device(md, old_dev);
324 
325 	return 0;
326 }
327 
328 /*
329  * Convert the path to a device
330  */
dm_get_dev_t(const char * path)331 dev_t dm_get_dev_t(const char *path)
332 {
333 	dev_t dev;
334 
335 	if (lookup_bdev(path, &dev))
336 		dev = name_to_dev_t(path);
337 	return dev;
338 }
339 EXPORT_SYMBOL_GPL(dm_get_dev_t);
340 
341 /*
342  * Add a device to the list, or just increment the usage count if
343  * it's already present.
344  */
dm_get_device(struct dm_target * ti,const char * path,fmode_t mode,struct dm_dev ** result)345 int dm_get_device(struct dm_target *ti, const char *path, fmode_t mode,
346 		  struct dm_dev **result)
347 {
348 	int r;
349 	dev_t dev;
350 	unsigned int major, minor;
351 	char dummy;
352 	struct dm_dev_internal *dd;
353 	struct dm_table *t = ti->table;
354 
355 	BUG_ON(!t);
356 
357 	if (sscanf(path, "%u:%u%c", &major, &minor, &dummy) == 2) {
358 		/* Extract the major/minor numbers */
359 		dev = MKDEV(major, minor);
360 		if (MAJOR(dev) != major || MINOR(dev) != minor)
361 			return -EOVERFLOW;
362 	} else {
363 		dev = dm_get_dev_t(path);
364 		if (!dev)
365 			return -ENODEV;
366 	}
367 
368 	dd = find_device(&t->devices, dev);
369 	if (!dd) {
370 		dd = kmalloc(sizeof(*dd), GFP_KERNEL);
371 		if (!dd)
372 			return -ENOMEM;
373 
374 		if ((r = dm_get_table_device(t->md, dev, mode, &dd->dm_dev))) {
375 			kfree(dd);
376 			return r;
377 		}
378 
379 		refcount_set(&dd->count, 1);
380 		list_add(&dd->list, &t->devices);
381 		goto out;
382 
383 	} else if (dd->dm_dev->mode != (mode | dd->dm_dev->mode)) {
384 		r = upgrade_mode(dd, mode, t->md);
385 		if (r)
386 			return r;
387 	}
388 	refcount_inc(&dd->count);
389 out:
390 	*result = dd->dm_dev;
391 	return 0;
392 }
393 EXPORT_SYMBOL(dm_get_device);
394 
dm_set_device_limits(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)395 static int dm_set_device_limits(struct dm_target *ti, struct dm_dev *dev,
396 				sector_t start, sector_t len, void *data)
397 {
398 	struct queue_limits *limits = data;
399 	struct block_device *bdev = dev->bdev;
400 	struct request_queue *q = bdev_get_queue(bdev);
401 
402 	if (unlikely(!q)) {
403 		DMWARN("%s: Cannot set limits for nonexistent device %pg",
404 		       dm_device_name(ti->table->md), bdev);
405 		return 0;
406 	}
407 
408 	if (blk_stack_limits(limits, &q->limits,
409 			get_start_sect(bdev) + start) < 0)
410 		DMWARN("%s: adding target device %pg caused an alignment inconsistency: "
411 		       "physical_block_size=%u, logical_block_size=%u, "
412 		       "alignment_offset=%u, start=%llu",
413 		       dm_device_name(ti->table->md), bdev,
414 		       q->limits.physical_block_size,
415 		       q->limits.logical_block_size,
416 		       q->limits.alignment_offset,
417 		       (unsigned long long) start << SECTOR_SHIFT);
418 	return 0;
419 }
420 
421 /*
422  * Decrement a device's use count and remove it if necessary.
423  */
dm_put_device(struct dm_target * ti,struct dm_dev * d)424 void dm_put_device(struct dm_target *ti, struct dm_dev *d)
425 {
426 	int found = 0;
427 	struct list_head *devices = &ti->table->devices;
428 	struct dm_dev_internal *dd;
429 
430 	list_for_each_entry(dd, devices, list) {
431 		if (dd->dm_dev == d) {
432 			found = 1;
433 			break;
434 		}
435 	}
436 	if (!found) {
437 		DMERR("%s: device %s not in table devices list",
438 		      dm_device_name(ti->table->md), d->name);
439 		return;
440 	}
441 	if (refcount_dec_and_test(&dd->count)) {
442 		dm_put_table_device(ti->table->md, d);
443 		list_del(&dd->list);
444 		kfree(dd);
445 	}
446 }
447 EXPORT_SYMBOL(dm_put_device);
448 
449 /*
450  * Checks to see if the target joins onto the end of the table.
451  */
adjoin(struct dm_table * t,struct dm_target * ti)452 static int adjoin(struct dm_table *t, struct dm_target *ti)
453 {
454 	struct dm_target *prev;
455 
456 	if (!t->num_targets)
457 		return !ti->begin;
458 
459 	prev = &t->targets[t->num_targets - 1];
460 	return (ti->begin == (prev->begin + prev->len));
461 }
462 
463 /*
464  * Used to dynamically allocate the arg array.
465  *
466  * We do first allocation with GFP_NOIO because dm-mpath and dm-thin must
467  * process messages even if some device is suspended. These messages have a
468  * small fixed number of arguments.
469  *
470  * On the other hand, dm-switch needs to process bulk data using messages and
471  * excessive use of GFP_NOIO could cause trouble.
472  */
realloc_argv(unsigned * size,char ** old_argv)473 static char **realloc_argv(unsigned *size, char **old_argv)
474 {
475 	char **argv;
476 	unsigned new_size;
477 	gfp_t gfp;
478 
479 	if (*size) {
480 		new_size = *size * 2;
481 		gfp = GFP_KERNEL;
482 	} else {
483 		new_size = 8;
484 		gfp = GFP_NOIO;
485 	}
486 	argv = kmalloc_array(new_size, sizeof(*argv), gfp);
487 	if (argv && old_argv) {
488 		memcpy(argv, old_argv, *size * sizeof(*argv));
489 		*size = new_size;
490 	}
491 
492 	kfree(old_argv);
493 	return argv;
494 }
495 
496 /*
497  * Destructively splits up the argument list to pass to ctr.
498  */
dm_split_args(int * argc,char *** argvp,char * input)499 int dm_split_args(int *argc, char ***argvp, char *input)
500 {
501 	char *start, *end = input, *out, **argv = NULL;
502 	unsigned array_size = 0;
503 
504 	*argc = 0;
505 
506 	if (!input) {
507 		*argvp = NULL;
508 		return 0;
509 	}
510 
511 	argv = realloc_argv(&array_size, argv);
512 	if (!argv)
513 		return -ENOMEM;
514 
515 	while (1) {
516 		/* Skip whitespace */
517 		start = skip_spaces(end);
518 
519 		if (!*start)
520 			break;	/* success, we hit the end */
521 
522 		/* 'out' is used to remove any back-quotes */
523 		end = out = start;
524 		while (*end) {
525 			/* Everything apart from '\0' can be quoted */
526 			if (*end == '\\' && *(end + 1)) {
527 				*out++ = *(end + 1);
528 				end += 2;
529 				continue;
530 			}
531 
532 			if (isspace(*end))
533 				break;	/* end of token */
534 
535 			*out++ = *end++;
536 		}
537 
538 		/* have we already filled the array ? */
539 		if ((*argc + 1) > array_size) {
540 			argv = realloc_argv(&array_size, argv);
541 			if (!argv)
542 				return -ENOMEM;
543 		}
544 
545 		/* we know this is whitespace */
546 		if (*end)
547 			end++;
548 
549 		/* terminate the string and put it in the array */
550 		*out = '\0';
551 		argv[*argc] = start;
552 		(*argc)++;
553 	}
554 
555 	*argvp = argv;
556 	return 0;
557 }
558 
559 /*
560  * Impose necessary and sufficient conditions on a devices's table such
561  * that any incoming bio which respects its logical_block_size can be
562  * processed successfully.  If it falls across the boundary between
563  * two or more targets, the size of each piece it gets split into must
564  * be compatible with the logical_block_size of the target processing it.
565  */
validate_hardware_logical_block_alignment(struct dm_table * t,struct queue_limits * limits)566 static int validate_hardware_logical_block_alignment(struct dm_table *t,
567 						     struct queue_limits *limits)
568 {
569 	/*
570 	 * This function uses arithmetic modulo the logical_block_size
571 	 * (in units of 512-byte sectors).
572 	 */
573 	unsigned short device_logical_block_size_sects =
574 		limits->logical_block_size >> SECTOR_SHIFT;
575 
576 	/*
577 	 * Offset of the start of the next table entry, mod logical_block_size.
578 	 */
579 	unsigned short next_target_start = 0;
580 
581 	/*
582 	 * Given an aligned bio that extends beyond the end of a
583 	 * target, how many sectors must the next target handle?
584 	 */
585 	unsigned short remaining = 0;
586 
587 	struct dm_target *ti;
588 	struct queue_limits ti_limits;
589 	unsigned int i;
590 
591 	/*
592 	 * Check each entry in the table in turn.
593 	 */
594 	for (i = 0; i < t->num_targets; i++) {
595 		ti = dm_table_get_target(t, i);
596 
597 		blk_set_stacking_limits(&ti_limits);
598 
599 		/* combine all target devices' limits */
600 		if (ti->type->iterate_devices)
601 			ti->type->iterate_devices(ti, dm_set_device_limits,
602 						  &ti_limits);
603 
604 		/*
605 		 * If the remaining sectors fall entirely within this
606 		 * table entry are they compatible with its logical_block_size?
607 		 */
608 		if (remaining < ti->len &&
609 		    remaining & ((ti_limits.logical_block_size >>
610 				  SECTOR_SHIFT) - 1))
611 			break;	/* Error */
612 
613 		next_target_start =
614 		    (unsigned short) ((next_target_start + ti->len) &
615 				      (device_logical_block_size_sects - 1));
616 		remaining = next_target_start ?
617 		    device_logical_block_size_sects - next_target_start : 0;
618 	}
619 
620 	if (remaining) {
621 		DMERR("%s: table line %u (start sect %llu len %llu) "
622 		      "not aligned to h/w logical block size %u",
623 		      dm_device_name(t->md), i,
624 		      (unsigned long long) ti->begin,
625 		      (unsigned long long) ti->len,
626 		      limits->logical_block_size);
627 		return -EINVAL;
628 	}
629 
630 	return 0;
631 }
632 
dm_table_add_target(struct dm_table * t,const char * type,sector_t start,sector_t len,char * params)633 int dm_table_add_target(struct dm_table *t, const char *type,
634 			sector_t start, sector_t len, char *params)
635 {
636 	int r = -EINVAL, argc;
637 	char **argv;
638 	struct dm_target *ti;
639 
640 	if (t->singleton) {
641 		DMERR("%s: target type %s must appear alone in table",
642 		      dm_device_name(t->md), t->targets->type->name);
643 		return -EINVAL;
644 	}
645 
646 	BUG_ON(t->num_targets >= t->num_allocated);
647 
648 	ti = t->targets + t->num_targets;
649 	memset(ti, 0, sizeof(*ti));
650 
651 	if (!len) {
652 		DMERR("%s: zero-length target", dm_device_name(t->md));
653 		return -EINVAL;
654 	}
655 
656 	ti->type = dm_get_target_type(type);
657 	if (!ti->type) {
658 		DMERR("%s: %s: unknown target type", dm_device_name(t->md), type);
659 		return -EINVAL;
660 	}
661 
662 	if (dm_target_needs_singleton(ti->type)) {
663 		if (t->num_targets) {
664 			ti->error = "singleton target type must appear alone in table";
665 			goto bad;
666 		}
667 		t->singleton = true;
668 	}
669 
670 	if (dm_target_always_writeable(ti->type) && !(t->mode & FMODE_WRITE)) {
671 		ti->error = "target type may not be included in a read-only table";
672 		goto bad;
673 	}
674 
675 	if (t->immutable_target_type) {
676 		if (t->immutable_target_type != ti->type) {
677 			ti->error = "immutable target type cannot be mixed with other target types";
678 			goto bad;
679 		}
680 	} else if (dm_target_is_immutable(ti->type)) {
681 		if (t->num_targets) {
682 			ti->error = "immutable target type cannot be mixed with other target types";
683 			goto bad;
684 		}
685 		t->immutable_target_type = ti->type;
686 	}
687 
688 	if (dm_target_has_integrity(ti->type))
689 		t->integrity_added = 1;
690 
691 	ti->table = t;
692 	ti->begin = start;
693 	ti->len = len;
694 	ti->error = "Unknown error";
695 
696 	/*
697 	 * Does this target adjoin the previous one ?
698 	 */
699 	if (!adjoin(t, ti)) {
700 		ti->error = "Gap in table";
701 		goto bad;
702 	}
703 
704 	r = dm_split_args(&argc, &argv, params);
705 	if (r) {
706 		ti->error = "couldn't split parameters";
707 		goto bad;
708 	}
709 
710 	r = ti->type->ctr(ti, argc, argv);
711 	kfree(argv);
712 	if (r)
713 		goto bad;
714 
715 	t->highs[t->num_targets++] = ti->begin + ti->len - 1;
716 
717 	if (!ti->num_discard_bios && ti->discards_supported)
718 		DMWARN("%s: %s: ignoring discards_supported because num_discard_bios is zero.",
719 		       dm_device_name(t->md), type);
720 
721 	if (ti->limit_swap_bios && !static_key_enabled(&swap_bios_enabled.key))
722 		static_branch_enable(&swap_bios_enabled);
723 
724 	return 0;
725 
726  bad:
727 	DMERR("%s: %s: %s (%pe)", dm_device_name(t->md), type, ti->error, ERR_PTR(r));
728 	dm_put_target_type(ti->type);
729 	return r;
730 }
731 
732 /*
733  * Target argument parsing helpers.
734  */
validate_next_arg(const struct dm_arg * arg,struct dm_arg_set * arg_set,unsigned * value,char ** error,unsigned grouped)735 static int validate_next_arg(const struct dm_arg *arg,
736 			     struct dm_arg_set *arg_set,
737 			     unsigned *value, char **error, unsigned grouped)
738 {
739 	const char *arg_str = dm_shift_arg(arg_set);
740 	char dummy;
741 
742 	if (!arg_str ||
743 	    (sscanf(arg_str, "%u%c", value, &dummy) != 1) ||
744 	    (*value < arg->min) ||
745 	    (*value > arg->max) ||
746 	    (grouped && arg_set->argc < *value)) {
747 		*error = arg->error;
748 		return -EINVAL;
749 	}
750 
751 	return 0;
752 }
753 
dm_read_arg(const struct dm_arg * arg,struct dm_arg_set * arg_set,unsigned * value,char ** error)754 int dm_read_arg(const struct dm_arg *arg, struct dm_arg_set *arg_set,
755 		unsigned *value, char **error)
756 {
757 	return validate_next_arg(arg, arg_set, value, error, 0);
758 }
759 EXPORT_SYMBOL(dm_read_arg);
760 
dm_read_arg_group(const struct dm_arg * arg,struct dm_arg_set * arg_set,unsigned * value,char ** error)761 int dm_read_arg_group(const struct dm_arg *arg, struct dm_arg_set *arg_set,
762 		      unsigned *value, char **error)
763 {
764 	return validate_next_arg(arg, arg_set, value, error, 1);
765 }
766 EXPORT_SYMBOL(dm_read_arg_group);
767 
dm_shift_arg(struct dm_arg_set * as)768 const char *dm_shift_arg(struct dm_arg_set *as)
769 {
770 	char *r;
771 
772 	if (as->argc) {
773 		as->argc--;
774 		r = *as->argv;
775 		as->argv++;
776 		return r;
777 	}
778 
779 	return NULL;
780 }
781 EXPORT_SYMBOL(dm_shift_arg);
782 
dm_consume_args(struct dm_arg_set * as,unsigned num_args)783 void dm_consume_args(struct dm_arg_set *as, unsigned num_args)
784 {
785 	BUG_ON(as->argc < num_args);
786 	as->argc -= num_args;
787 	as->argv += num_args;
788 }
789 EXPORT_SYMBOL(dm_consume_args);
790 
__table_type_bio_based(enum dm_queue_mode table_type)791 static bool __table_type_bio_based(enum dm_queue_mode table_type)
792 {
793 	return (table_type == DM_TYPE_BIO_BASED ||
794 		table_type == DM_TYPE_DAX_BIO_BASED);
795 }
796 
__table_type_request_based(enum dm_queue_mode table_type)797 static bool __table_type_request_based(enum dm_queue_mode table_type)
798 {
799 	return table_type == DM_TYPE_REQUEST_BASED;
800 }
801 
dm_table_set_type(struct dm_table * t,enum dm_queue_mode type)802 void dm_table_set_type(struct dm_table *t, enum dm_queue_mode type)
803 {
804 	t->type = type;
805 }
806 EXPORT_SYMBOL_GPL(dm_table_set_type);
807 
808 /* validate the dax capability of the target device span */
device_not_dax_capable(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)809 static int device_not_dax_capable(struct dm_target *ti, struct dm_dev *dev,
810 			sector_t start, sector_t len, void *data)
811 {
812 	if (dev->dax_dev)
813 		return false;
814 
815 	DMDEBUG("%pg: error: dax unsupported by block device", dev->bdev);
816 	return true;
817 }
818 
819 /* Check devices support synchronous DAX */
device_not_dax_synchronous_capable(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)820 static int device_not_dax_synchronous_capable(struct dm_target *ti, struct dm_dev *dev,
821 					      sector_t start, sector_t len, void *data)
822 {
823 	return !dev->dax_dev || !dax_synchronous(dev->dax_dev);
824 }
825 
dm_table_supports_dax(struct dm_table * t,iterate_devices_callout_fn iterate_fn)826 static bool dm_table_supports_dax(struct dm_table *t,
827 				  iterate_devices_callout_fn iterate_fn)
828 {
829 	/* Ensure that all targets support DAX. */
830 	for (unsigned int i = 0; i < t->num_targets; i++) {
831 		struct dm_target *ti = dm_table_get_target(t, i);
832 
833 		if (!ti->type->direct_access)
834 			return false;
835 
836 		if (!ti->type->iterate_devices ||
837 		    ti->type->iterate_devices(ti, iterate_fn, NULL))
838 			return false;
839 	}
840 
841 	return true;
842 }
843 
device_is_rq_stackable(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)844 static int device_is_rq_stackable(struct dm_target *ti, struct dm_dev *dev,
845 				  sector_t start, sector_t len, void *data)
846 {
847 	struct block_device *bdev = dev->bdev;
848 	struct request_queue *q = bdev_get_queue(bdev);
849 
850 	/* request-based cannot stack on partitions! */
851 	if (bdev_is_partition(bdev))
852 		return false;
853 
854 	return queue_is_mq(q);
855 }
856 
dm_table_determine_type(struct dm_table * t)857 static int dm_table_determine_type(struct dm_table *t)
858 {
859 	unsigned bio_based = 0, request_based = 0, hybrid = 0;
860 	struct dm_target *ti;
861 	struct list_head *devices = dm_table_get_devices(t);
862 	enum dm_queue_mode live_md_type = dm_get_md_type(t->md);
863 
864 	if (t->type != DM_TYPE_NONE) {
865 		/* target already set the table's type */
866 		if (t->type == DM_TYPE_BIO_BASED) {
867 			/* possibly upgrade to a variant of bio-based */
868 			goto verify_bio_based;
869 		}
870 		BUG_ON(t->type == DM_TYPE_DAX_BIO_BASED);
871 		goto verify_rq_based;
872 	}
873 
874 	for (unsigned int i = 0; i < t->num_targets; i++) {
875 		ti = dm_table_get_target(t, i);
876 		if (dm_target_hybrid(ti))
877 			hybrid = 1;
878 		else if (dm_target_request_based(ti))
879 			request_based = 1;
880 		else
881 			bio_based = 1;
882 
883 		if (bio_based && request_based) {
884 			DMERR("Inconsistent table: different target types"
885 			      " can't be mixed up");
886 			return -EINVAL;
887 		}
888 	}
889 
890 	if (hybrid && !bio_based && !request_based) {
891 		/*
892 		 * The targets can work either way.
893 		 * Determine the type from the live device.
894 		 * Default to bio-based if device is new.
895 		 */
896 		if (__table_type_request_based(live_md_type))
897 			request_based = 1;
898 		else
899 			bio_based = 1;
900 	}
901 
902 	if (bio_based) {
903 verify_bio_based:
904 		/* We must use this table as bio-based */
905 		t->type = DM_TYPE_BIO_BASED;
906 		if (dm_table_supports_dax(t, device_not_dax_capable) ||
907 		    (list_empty(devices) && live_md_type == DM_TYPE_DAX_BIO_BASED)) {
908 			t->type = DM_TYPE_DAX_BIO_BASED;
909 		}
910 		return 0;
911 	}
912 
913 	BUG_ON(!request_based); /* No targets in this table */
914 
915 	t->type = DM_TYPE_REQUEST_BASED;
916 
917 verify_rq_based:
918 	/*
919 	 * Request-based dm supports only tables that have a single target now.
920 	 * To support multiple targets, request splitting support is needed,
921 	 * and that needs lots of changes in the block-layer.
922 	 * (e.g. request completion process for partial completion.)
923 	 */
924 	if (t->num_targets > 1) {
925 		DMERR("request-based DM doesn't support multiple targets");
926 		return -EINVAL;
927 	}
928 
929 	if (list_empty(devices)) {
930 		int srcu_idx;
931 		struct dm_table *live_table = dm_get_live_table(t->md, &srcu_idx);
932 
933 		/* inherit live table's type */
934 		if (live_table)
935 			t->type = live_table->type;
936 		dm_put_live_table(t->md, srcu_idx);
937 		return 0;
938 	}
939 
940 	ti = dm_table_get_immutable_target(t);
941 	if (!ti) {
942 		DMERR("table load rejected: immutable target is required");
943 		return -EINVAL;
944 	} else if (ti->max_io_len) {
945 		DMERR("table load rejected: immutable target that splits IO is not supported");
946 		return -EINVAL;
947 	}
948 
949 	/* Non-request-stackable devices can't be used for request-based dm */
950 	if (!ti->type->iterate_devices ||
951 	    !ti->type->iterate_devices(ti, device_is_rq_stackable, NULL)) {
952 		DMERR("table load rejected: including non-request-stackable devices");
953 		return -EINVAL;
954 	}
955 
956 	return 0;
957 }
958 
dm_table_get_type(struct dm_table * t)959 enum dm_queue_mode dm_table_get_type(struct dm_table *t)
960 {
961 	return t->type;
962 }
963 
dm_table_get_immutable_target_type(struct dm_table * t)964 struct target_type *dm_table_get_immutable_target_type(struct dm_table *t)
965 {
966 	return t->immutable_target_type;
967 }
968 
dm_table_get_immutable_target(struct dm_table * t)969 struct dm_target *dm_table_get_immutable_target(struct dm_table *t)
970 {
971 	/* Immutable target is implicitly a singleton */
972 	if (t->num_targets > 1 ||
973 	    !dm_target_is_immutable(t->targets[0].type))
974 		return NULL;
975 
976 	return t->targets;
977 }
978 
dm_table_get_wildcard_target(struct dm_table * t)979 struct dm_target *dm_table_get_wildcard_target(struct dm_table *t)
980 {
981 	for (unsigned int i = 0; i < t->num_targets; i++) {
982 		struct dm_target *ti = dm_table_get_target(t, i);
983 
984 		if (dm_target_is_wildcard(ti->type))
985 			return ti;
986 	}
987 
988 	return NULL;
989 }
990 
dm_table_bio_based(struct dm_table * t)991 bool dm_table_bio_based(struct dm_table *t)
992 {
993 	return __table_type_bio_based(dm_table_get_type(t));
994 }
995 
dm_table_request_based(struct dm_table * t)996 bool dm_table_request_based(struct dm_table *t)
997 {
998 	return __table_type_request_based(dm_table_get_type(t));
999 }
1000 
1001 static bool dm_table_supports_poll(struct dm_table *t);
1002 
dm_table_alloc_md_mempools(struct dm_table * t,struct mapped_device * md)1003 static int dm_table_alloc_md_mempools(struct dm_table *t, struct mapped_device *md)
1004 {
1005 	enum dm_queue_mode type = dm_table_get_type(t);
1006 	unsigned int per_io_data_size = 0, front_pad, io_front_pad;
1007 	unsigned int min_pool_size = 0, pool_size;
1008 	struct dm_md_mempools *pools;
1009 
1010 	if (unlikely(type == DM_TYPE_NONE)) {
1011 		DMERR("no table type is set, can't allocate mempools");
1012 		return -EINVAL;
1013 	}
1014 
1015 	pools = kzalloc_node(sizeof(*pools), GFP_KERNEL, md->numa_node_id);
1016 	if (!pools)
1017 		return -ENOMEM;
1018 
1019 	if (type == DM_TYPE_REQUEST_BASED) {
1020 		pool_size = dm_get_reserved_rq_based_ios();
1021 		front_pad = offsetof(struct dm_rq_clone_bio_info, clone);
1022 		goto init_bs;
1023 	}
1024 
1025 	for (unsigned int i = 0; i < t->num_targets; i++) {
1026 		struct dm_target *ti = dm_table_get_target(t, i);
1027 
1028 		per_io_data_size = max(per_io_data_size, ti->per_io_data_size);
1029 		min_pool_size = max(min_pool_size, ti->num_flush_bios);
1030 	}
1031 	pool_size = max(dm_get_reserved_bio_based_ios(), min_pool_size);
1032 	front_pad = roundup(per_io_data_size,
1033 		__alignof__(struct dm_target_io)) + DM_TARGET_IO_BIO_OFFSET;
1034 
1035 	io_front_pad = roundup(per_io_data_size,
1036 		__alignof__(struct dm_io)) + DM_IO_BIO_OFFSET;
1037 	if (bioset_init(&pools->io_bs, pool_size, io_front_pad,
1038 			dm_table_supports_poll(t) ? BIOSET_PERCPU_CACHE : 0))
1039 		goto out_free_pools;
1040 	if (t->integrity_supported &&
1041 	    bioset_integrity_create(&pools->io_bs, pool_size))
1042 		goto out_free_pools;
1043 init_bs:
1044 	if (bioset_init(&pools->bs, pool_size, front_pad, 0))
1045 		goto out_free_pools;
1046 	if (t->integrity_supported &&
1047 	    bioset_integrity_create(&pools->bs, pool_size))
1048 		goto out_free_pools;
1049 
1050 	t->mempools = pools;
1051 	return 0;
1052 
1053 out_free_pools:
1054 	dm_free_md_mempools(pools);
1055 	return -ENOMEM;
1056 }
1057 
setup_indexes(struct dm_table * t)1058 static int setup_indexes(struct dm_table *t)
1059 {
1060 	int i;
1061 	unsigned int total = 0;
1062 	sector_t *indexes;
1063 
1064 	/* allocate the space for *all* the indexes */
1065 	for (i = t->depth - 2; i >= 0; i--) {
1066 		t->counts[i] = dm_div_up(t->counts[i + 1], CHILDREN_PER_NODE);
1067 		total += t->counts[i];
1068 	}
1069 
1070 	indexes = kvcalloc(total, NODE_SIZE, GFP_KERNEL);
1071 	if (!indexes)
1072 		return -ENOMEM;
1073 
1074 	/* set up internal nodes, bottom-up */
1075 	for (i = t->depth - 2; i >= 0; i--) {
1076 		t->index[i] = indexes;
1077 		indexes += (KEYS_PER_NODE * t->counts[i]);
1078 		setup_btree_index(i, t);
1079 	}
1080 
1081 	return 0;
1082 }
1083 
1084 /*
1085  * Builds the btree to index the map.
1086  */
dm_table_build_index(struct dm_table * t)1087 static int dm_table_build_index(struct dm_table *t)
1088 {
1089 	int r = 0;
1090 	unsigned int leaf_nodes;
1091 
1092 	/* how many indexes will the btree have ? */
1093 	leaf_nodes = dm_div_up(t->num_targets, KEYS_PER_NODE);
1094 	t->depth = 1 + int_log(leaf_nodes, CHILDREN_PER_NODE);
1095 
1096 	/* leaf layer has already been set up */
1097 	t->counts[t->depth - 1] = leaf_nodes;
1098 	t->index[t->depth - 1] = t->highs;
1099 
1100 	if (t->depth >= 2)
1101 		r = setup_indexes(t);
1102 
1103 	return r;
1104 }
1105 
integrity_profile_exists(struct gendisk * disk)1106 static bool integrity_profile_exists(struct gendisk *disk)
1107 {
1108 	return !!blk_get_integrity(disk);
1109 }
1110 
1111 /*
1112  * Get a disk whose integrity profile reflects the table's profile.
1113  * Returns NULL if integrity support was inconsistent or unavailable.
1114  */
dm_table_get_integrity_disk(struct dm_table * t)1115 static struct gendisk *dm_table_get_integrity_disk(struct dm_table *t)
1116 {
1117 	struct list_head *devices = dm_table_get_devices(t);
1118 	struct dm_dev_internal *dd = NULL;
1119 	struct gendisk *prev_disk = NULL, *template_disk = NULL;
1120 
1121 	for (unsigned int i = 0; i < t->num_targets; i++) {
1122 		struct dm_target *ti = dm_table_get_target(t, i);
1123 
1124 		if (!dm_target_passes_integrity(ti->type))
1125 			goto no_integrity;
1126 	}
1127 
1128 	list_for_each_entry(dd, devices, list) {
1129 		template_disk = dd->dm_dev->bdev->bd_disk;
1130 		if (!integrity_profile_exists(template_disk))
1131 			goto no_integrity;
1132 		else if (prev_disk &&
1133 			 blk_integrity_compare(prev_disk, template_disk) < 0)
1134 			goto no_integrity;
1135 		prev_disk = template_disk;
1136 	}
1137 
1138 	return template_disk;
1139 
1140 no_integrity:
1141 	if (prev_disk)
1142 		DMWARN("%s: integrity not set: %s and %s profile mismatch",
1143 		       dm_device_name(t->md),
1144 		       prev_disk->disk_name,
1145 		       template_disk->disk_name);
1146 	return NULL;
1147 }
1148 
1149 /*
1150  * Register the mapped device for blk_integrity support if the
1151  * underlying devices have an integrity profile.  But all devices may
1152  * not have matching profiles (checking all devices isn't reliable
1153  * during table load because this table may use other DM device(s) which
1154  * must be resumed before they will have an initialized integity
1155  * profile).  Consequently, stacked DM devices force a 2 stage integrity
1156  * profile validation: First pass during table load, final pass during
1157  * resume.
1158  */
dm_table_register_integrity(struct dm_table * t)1159 static int dm_table_register_integrity(struct dm_table *t)
1160 {
1161 	struct mapped_device *md = t->md;
1162 	struct gendisk *template_disk = NULL;
1163 
1164 	/* If target handles integrity itself do not register it here. */
1165 	if (t->integrity_added)
1166 		return 0;
1167 
1168 	template_disk = dm_table_get_integrity_disk(t);
1169 	if (!template_disk)
1170 		return 0;
1171 
1172 	if (!integrity_profile_exists(dm_disk(md))) {
1173 		t->integrity_supported = true;
1174 		/*
1175 		 * Register integrity profile during table load; we can do
1176 		 * this because the final profile must match during resume.
1177 		 */
1178 		blk_integrity_register(dm_disk(md),
1179 				       blk_get_integrity(template_disk));
1180 		return 0;
1181 	}
1182 
1183 	/*
1184 	 * If DM device already has an initialized integrity
1185 	 * profile the new profile should not conflict.
1186 	 */
1187 	if (blk_integrity_compare(dm_disk(md), template_disk) < 0) {
1188 		DMERR("%s: conflict with existing integrity profile: "
1189 		      "%s profile mismatch",
1190 		      dm_device_name(t->md),
1191 		      template_disk->disk_name);
1192 		return 1;
1193 	}
1194 
1195 	/* Preserve existing integrity profile */
1196 	t->integrity_supported = true;
1197 	return 0;
1198 }
1199 
1200 #ifdef CONFIG_BLK_INLINE_ENCRYPTION
1201 
1202 struct dm_crypto_profile {
1203 	struct blk_crypto_profile profile;
1204 	struct mapped_device *md;
1205 };
1206 
1207 struct dm_keyslot_evict_args {
1208 	const struct blk_crypto_key *key;
1209 	int err;
1210 };
1211 
dm_keyslot_evict_callback(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)1212 static int dm_keyslot_evict_callback(struct dm_target *ti, struct dm_dev *dev,
1213 				     sector_t start, sector_t len, void *data)
1214 {
1215 	struct dm_keyslot_evict_args *args = data;
1216 	int err;
1217 
1218 	err = blk_crypto_evict_key(bdev_get_queue(dev->bdev), args->key);
1219 	if (!args->err)
1220 		args->err = err;
1221 	/* Always try to evict the key from all devices. */
1222 	return 0;
1223 }
1224 
1225 /*
1226  * When an inline encryption key is evicted from a device-mapper device, evict
1227  * it from all the underlying devices.
1228  */
dm_keyslot_evict(struct blk_crypto_profile * profile,const struct blk_crypto_key * key,unsigned int slot)1229 static int dm_keyslot_evict(struct blk_crypto_profile *profile,
1230 			    const struct blk_crypto_key *key, unsigned int slot)
1231 {
1232 	struct mapped_device *md =
1233 		container_of(profile, struct dm_crypto_profile, profile)->md;
1234 	struct dm_keyslot_evict_args args = { key };
1235 	struct dm_table *t;
1236 	int srcu_idx;
1237 
1238 	t = dm_get_live_table(md, &srcu_idx);
1239 	if (!t)
1240 		return 0;
1241 
1242 	for (unsigned int i = 0; i < t->num_targets; i++) {
1243 		struct dm_target *ti = dm_table_get_target(t, i);
1244 
1245 		if (!ti->type->iterate_devices)
1246 			continue;
1247 		ti->type->iterate_devices(ti, dm_keyslot_evict_callback, &args);
1248 	}
1249 
1250 	dm_put_live_table(md, srcu_idx);
1251 	return args.err;
1252 }
1253 
1254 static int
device_intersect_crypto_capabilities(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)1255 device_intersect_crypto_capabilities(struct dm_target *ti, struct dm_dev *dev,
1256 				     sector_t start, sector_t len, void *data)
1257 {
1258 	struct blk_crypto_profile *parent = data;
1259 	struct blk_crypto_profile *child =
1260 		bdev_get_queue(dev->bdev)->crypto_profile;
1261 
1262 	blk_crypto_intersect_capabilities(parent, child);
1263 	return 0;
1264 }
1265 
dm_destroy_crypto_profile(struct blk_crypto_profile * profile)1266 void dm_destroy_crypto_profile(struct blk_crypto_profile *profile)
1267 {
1268 	struct dm_crypto_profile *dmcp = container_of(profile,
1269 						      struct dm_crypto_profile,
1270 						      profile);
1271 
1272 	if (!profile)
1273 		return;
1274 
1275 	blk_crypto_profile_destroy(profile);
1276 	kfree(dmcp);
1277 }
1278 
dm_table_destroy_crypto_profile(struct dm_table * t)1279 static void dm_table_destroy_crypto_profile(struct dm_table *t)
1280 {
1281 	dm_destroy_crypto_profile(t->crypto_profile);
1282 	t->crypto_profile = NULL;
1283 }
1284 
1285 /*
1286  * Constructs and initializes t->crypto_profile with a crypto profile that
1287  * represents the common set of crypto capabilities of the devices described by
1288  * the dm_table.  However, if the constructed crypto profile doesn't support all
1289  * crypto capabilities that are supported by the current mapped_device, it
1290  * returns an error instead, since we don't support removing crypto capabilities
1291  * on table changes.  Finally, if the constructed crypto profile is "empty" (has
1292  * no crypto capabilities at all), it just sets t->crypto_profile to NULL.
1293  */
dm_table_construct_crypto_profile(struct dm_table * t)1294 static int dm_table_construct_crypto_profile(struct dm_table *t)
1295 {
1296 	struct dm_crypto_profile *dmcp;
1297 	struct blk_crypto_profile *profile;
1298 	unsigned int i;
1299 	bool empty_profile = true;
1300 
1301 	dmcp = kmalloc(sizeof(*dmcp), GFP_KERNEL);
1302 	if (!dmcp)
1303 		return -ENOMEM;
1304 	dmcp->md = t->md;
1305 
1306 	profile = &dmcp->profile;
1307 	blk_crypto_profile_init(profile, 0);
1308 	profile->ll_ops.keyslot_evict = dm_keyslot_evict;
1309 	profile->max_dun_bytes_supported = UINT_MAX;
1310 	memset(profile->modes_supported, 0xFF,
1311 	       sizeof(profile->modes_supported));
1312 
1313 	for (i = 0; i < t->num_targets; i++) {
1314 		struct dm_target *ti = dm_table_get_target(t, i);
1315 
1316 		if (!dm_target_passes_crypto(ti->type)) {
1317 			blk_crypto_intersect_capabilities(profile, NULL);
1318 			break;
1319 		}
1320 		if (!ti->type->iterate_devices)
1321 			continue;
1322 		ti->type->iterate_devices(ti,
1323 					  device_intersect_crypto_capabilities,
1324 					  profile);
1325 	}
1326 
1327 	if (t->md->queue &&
1328 	    !blk_crypto_has_capabilities(profile,
1329 					 t->md->queue->crypto_profile)) {
1330 		DMERR("Inline encryption capabilities of new DM table were more restrictive than the old table's. This is not supported!");
1331 		dm_destroy_crypto_profile(profile);
1332 		return -EINVAL;
1333 	}
1334 
1335 	/*
1336 	 * If the new profile doesn't actually support any crypto capabilities,
1337 	 * we may as well represent it with a NULL profile.
1338 	 */
1339 	for (i = 0; i < ARRAY_SIZE(profile->modes_supported); i++) {
1340 		if (profile->modes_supported[i]) {
1341 			empty_profile = false;
1342 			break;
1343 		}
1344 	}
1345 
1346 	if (empty_profile) {
1347 		dm_destroy_crypto_profile(profile);
1348 		profile = NULL;
1349 	}
1350 
1351 	/*
1352 	 * t->crypto_profile is only set temporarily while the table is being
1353 	 * set up, and it gets set to NULL after the profile has been
1354 	 * transferred to the request_queue.
1355 	 */
1356 	t->crypto_profile = profile;
1357 
1358 	return 0;
1359 }
1360 
dm_update_crypto_profile(struct request_queue * q,struct dm_table * t)1361 static void dm_update_crypto_profile(struct request_queue *q,
1362 				     struct dm_table *t)
1363 {
1364 	if (!t->crypto_profile)
1365 		return;
1366 
1367 	/* Make the crypto profile less restrictive. */
1368 	if (!q->crypto_profile) {
1369 		blk_crypto_register(t->crypto_profile, q);
1370 	} else {
1371 		blk_crypto_update_capabilities(q->crypto_profile,
1372 					       t->crypto_profile);
1373 		dm_destroy_crypto_profile(t->crypto_profile);
1374 	}
1375 	t->crypto_profile = NULL;
1376 }
1377 
1378 #else /* CONFIG_BLK_INLINE_ENCRYPTION */
1379 
dm_table_construct_crypto_profile(struct dm_table * t)1380 static int dm_table_construct_crypto_profile(struct dm_table *t)
1381 {
1382 	return 0;
1383 }
1384 
dm_destroy_crypto_profile(struct blk_crypto_profile * profile)1385 void dm_destroy_crypto_profile(struct blk_crypto_profile *profile)
1386 {
1387 }
1388 
dm_table_destroy_crypto_profile(struct dm_table * t)1389 static void dm_table_destroy_crypto_profile(struct dm_table *t)
1390 {
1391 }
1392 
dm_update_crypto_profile(struct request_queue * q,struct dm_table * t)1393 static void dm_update_crypto_profile(struct request_queue *q,
1394 				     struct dm_table *t)
1395 {
1396 }
1397 
1398 #endif /* !CONFIG_BLK_INLINE_ENCRYPTION */
1399 
1400 /*
1401  * Prepares the table for use by building the indices,
1402  * setting the type, and allocating mempools.
1403  */
dm_table_complete(struct dm_table * t)1404 int dm_table_complete(struct dm_table *t)
1405 {
1406 	int r;
1407 
1408 	r = dm_table_determine_type(t);
1409 	if (r) {
1410 		DMERR("unable to determine table type");
1411 		return r;
1412 	}
1413 
1414 	r = dm_table_build_index(t);
1415 	if (r) {
1416 		DMERR("unable to build btrees");
1417 		return r;
1418 	}
1419 
1420 	r = dm_table_register_integrity(t);
1421 	if (r) {
1422 		DMERR("could not register integrity profile.");
1423 		return r;
1424 	}
1425 
1426 	r = dm_table_construct_crypto_profile(t);
1427 	if (r) {
1428 		DMERR("could not construct crypto profile.");
1429 		return r;
1430 	}
1431 
1432 	r = dm_table_alloc_md_mempools(t, t->md);
1433 	if (r)
1434 		DMERR("unable to allocate mempools");
1435 
1436 	return r;
1437 }
1438 
1439 static DEFINE_MUTEX(_event_lock);
dm_table_event_callback(struct dm_table * t,void (* fn)(void *),void * context)1440 void dm_table_event_callback(struct dm_table *t,
1441 			     void (*fn)(void *), void *context)
1442 {
1443 	mutex_lock(&_event_lock);
1444 	t->event_fn = fn;
1445 	t->event_context = context;
1446 	mutex_unlock(&_event_lock);
1447 }
1448 
dm_table_event(struct dm_table * t)1449 void dm_table_event(struct dm_table *t)
1450 {
1451 	mutex_lock(&_event_lock);
1452 	if (t->event_fn)
1453 		t->event_fn(t->event_context);
1454 	mutex_unlock(&_event_lock);
1455 }
1456 EXPORT_SYMBOL(dm_table_event);
1457 
dm_table_get_size(struct dm_table * t)1458 inline sector_t dm_table_get_size(struct dm_table *t)
1459 {
1460 	return t->num_targets ? (t->highs[t->num_targets - 1] + 1) : 0;
1461 }
1462 EXPORT_SYMBOL(dm_table_get_size);
1463 
1464 /*
1465  * Search the btree for the correct target.
1466  *
1467  * Caller should check returned pointer for NULL
1468  * to trap I/O beyond end of device.
1469  */
dm_table_find_target(struct dm_table * t,sector_t sector)1470 struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector)
1471 {
1472 	unsigned int l, n = 0, k = 0;
1473 	sector_t *node;
1474 
1475 	if (unlikely(sector >= dm_table_get_size(t)))
1476 		return NULL;
1477 
1478 	for (l = 0; l < t->depth; l++) {
1479 		n = get_child(n, k);
1480 		node = get_node(t, l, n);
1481 
1482 		for (k = 0; k < KEYS_PER_NODE; k++)
1483 			if (node[k] >= sector)
1484 				break;
1485 	}
1486 
1487 	return &t->targets[(KEYS_PER_NODE * n) + k];
1488 }
1489 
device_not_poll_capable(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)1490 static int device_not_poll_capable(struct dm_target *ti, struct dm_dev *dev,
1491 				   sector_t start, sector_t len, void *data)
1492 {
1493 	struct request_queue *q = bdev_get_queue(dev->bdev);
1494 
1495 	return !test_bit(QUEUE_FLAG_POLL, &q->queue_flags);
1496 }
1497 
1498 /*
1499  * type->iterate_devices() should be called when the sanity check needs to
1500  * iterate and check all underlying data devices. iterate_devices() will
1501  * iterate all underlying data devices until it encounters a non-zero return
1502  * code, returned by whether the input iterate_devices_callout_fn, or
1503  * iterate_devices() itself internally.
1504  *
1505  * For some target type (e.g. dm-stripe), one call of iterate_devices() may
1506  * iterate multiple underlying devices internally, in which case a non-zero
1507  * return code returned by iterate_devices_callout_fn will stop the iteration
1508  * in advance.
1509  *
1510  * Cases requiring _any_ underlying device supporting some kind of attribute,
1511  * should use the iteration structure like dm_table_any_dev_attr(), or call
1512  * it directly. @func should handle semantics of positive examples, e.g.
1513  * capable of something.
1514  *
1515  * Cases requiring _all_ underlying devices supporting some kind of attribute,
1516  * should use the iteration structure like dm_table_supports_nowait() or
1517  * dm_table_supports_discards(). Or introduce dm_table_all_devs_attr() that
1518  * uses an @anti_func that handle semantics of counter examples, e.g. not
1519  * capable of something. So: return !dm_table_any_dev_attr(t, anti_func, data);
1520  */
dm_table_any_dev_attr(struct dm_table * t,iterate_devices_callout_fn func,void * data)1521 static bool dm_table_any_dev_attr(struct dm_table *t,
1522 				  iterate_devices_callout_fn func, void *data)
1523 {
1524 	for (unsigned int i = 0; i < t->num_targets; i++) {
1525 		struct dm_target *ti = dm_table_get_target(t, i);
1526 
1527 		if (ti->type->iterate_devices &&
1528 		    ti->type->iterate_devices(ti, func, data))
1529 			return true;
1530         }
1531 
1532 	return false;
1533 }
1534 
count_device(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)1535 static int count_device(struct dm_target *ti, struct dm_dev *dev,
1536 			sector_t start, sector_t len, void *data)
1537 {
1538 	unsigned *num_devices = data;
1539 
1540 	(*num_devices)++;
1541 
1542 	return 0;
1543 }
1544 
dm_table_supports_poll(struct dm_table * t)1545 static bool dm_table_supports_poll(struct dm_table *t)
1546 {
1547 	for (unsigned int i = 0; i < t->num_targets; i++) {
1548 		struct dm_target *ti = dm_table_get_target(t, i);
1549 
1550 		if (!ti->type->iterate_devices ||
1551 		    ti->type->iterate_devices(ti, device_not_poll_capable, NULL))
1552 			return false;
1553 	}
1554 
1555 	return true;
1556 }
1557 
1558 /*
1559  * Check whether a table has no data devices attached using each
1560  * target's iterate_devices method.
1561  * Returns false if the result is unknown because a target doesn't
1562  * support iterate_devices.
1563  */
dm_table_has_no_data_devices(struct dm_table * t)1564 bool dm_table_has_no_data_devices(struct dm_table *t)
1565 {
1566 	for (unsigned int i = 0; i < t->num_targets; i++) {
1567 		struct dm_target *ti = dm_table_get_target(t, i);
1568 		unsigned num_devices = 0;
1569 
1570 		if (!ti->type->iterate_devices)
1571 			return false;
1572 
1573 		ti->type->iterate_devices(ti, count_device, &num_devices);
1574 		if (num_devices)
1575 			return false;
1576 	}
1577 
1578 	return true;
1579 }
1580 
device_not_zoned_model(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)1581 static int device_not_zoned_model(struct dm_target *ti, struct dm_dev *dev,
1582 				  sector_t start, sector_t len, void *data)
1583 {
1584 	struct request_queue *q = bdev_get_queue(dev->bdev);
1585 	enum blk_zoned_model *zoned_model = data;
1586 
1587 	return blk_queue_zoned_model(q) != *zoned_model;
1588 }
1589 
1590 /*
1591  * Check the device zoned model based on the target feature flag. If the target
1592  * has the DM_TARGET_ZONED_HM feature flag set, host-managed zoned devices are
1593  * also accepted but all devices must have the same zoned model. If the target
1594  * has the DM_TARGET_MIXED_ZONED_MODEL feature set, the devices can have any
1595  * zoned model with all zoned devices having the same zone size.
1596  */
dm_table_supports_zoned_model(struct dm_table * t,enum blk_zoned_model zoned_model)1597 static bool dm_table_supports_zoned_model(struct dm_table *t,
1598 					  enum blk_zoned_model zoned_model)
1599 {
1600 	for (unsigned int i = 0; i < t->num_targets; i++) {
1601 		struct dm_target *ti = dm_table_get_target(t, i);
1602 
1603 		if (dm_target_supports_zoned_hm(ti->type)) {
1604 			if (!ti->type->iterate_devices ||
1605 			    ti->type->iterate_devices(ti, device_not_zoned_model,
1606 						      &zoned_model))
1607 				return false;
1608 		} else if (!dm_target_supports_mixed_zoned_model(ti->type)) {
1609 			if (zoned_model == BLK_ZONED_HM)
1610 				return false;
1611 		}
1612 	}
1613 
1614 	return true;
1615 }
1616 
device_not_matches_zone_sectors(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)1617 static int device_not_matches_zone_sectors(struct dm_target *ti, struct dm_dev *dev,
1618 					   sector_t start, sector_t len, void *data)
1619 {
1620 	unsigned int *zone_sectors = data;
1621 
1622 	if (!bdev_is_zoned(dev->bdev))
1623 		return 0;
1624 	return bdev_zone_sectors(dev->bdev) != *zone_sectors;
1625 }
1626 
1627 /*
1628  * Check consistency of zoned model and zone sectors across all targets. For
1629  * zone sectors, if the destination device is a zoned block device, it shall
1630  * have the specified zone_sectors.
1631  */
validate_hardware_zoned_model(struct dm_table * t,enum blk_zoned_model zoned_model,unsigned int zone_sectors)1632 static int validate_hardware_zoned_model(struct dm_table *t,
1633 					 enum blk_zoned_model zoned_model,
1634 					 unsigned int zone_sectors)
1635 {
1636 	if (zoned_model == BLK_ZONED_NONE)
1637 		return 0;
1638 
1639 	if (!dm_table_supports_zoned_model(t, zoned_model)) {
1640 		DMERR("%s: zoned model is not consistent across all devices",
1641 		      dm_device_name(t->md));
1642 		return -EINVAL;
1643 	}
1644 
1645 	/* Check zone size validity and compatibility */
1646 	if (!zone_sectors || !is_power_of_2(zone_sectors))
1647 		return -EINVAL;
1648 
1649 	if (dm_table_any_dev_attr(t, device_not_matches_zone_sectors, &zone_sectors)) {
1650 		DMERR("%s: zone sectors is not consistent across all zoned devices",
1651 		      dm_device_name(t->md));
1652 		return -EINVAL;
1653 	}
1654 
1655 	return 0;
1656 }
1657 
1658 /*
1659  * Establish the new table's queue_limits and validate them.
1660  */
dm_calculate_queue_limits(struct dm_table * t,struct queue_limits * limits)1661 int dm_calculate_queue_limits(struct dm_table *t,
1662 			      struct queue_limits *limits)
1663 {
1664 	struct queue_limits ti_limits;
1665 	enum blk_zoned_model zoned_model = BLK_ZONED_NONE;
1666 	unsigned int zone_sectors = 0;
1667 
1668 	blk_set_stacking_limits(limits);
1669 
1670 	for (unsigned int i = 0; i < t->num_targets; i++) {
1671 		struct dm_target *ti = dm_table_get_target(t, i);
1672 
1673 		blk_set_stacking_limits(&ti_limits);
1674 
1675 		if (!ti->type->iterate_devices)
1676 			goto combine_limits;
1677 
1678 		/*
1679 		 * Combine queue limits of all the devices this target uses.
1680 		 */
1681 		ti->type->iterate_devices(ti, dm_set_device_limits,
1682 					  &ti_limits);
1683 
1684 		if (zoned_model == BLK_ZONED_NONE && ti_limits.zoned != BLK_ZONED_NONE) {
1685 			/*
1686 			 * After stacking all limits, validate all devices
1687 			 * in table support this zoned model and zone sectors.
1688 			 */
1689 			zoned_model = ti_limits.zoned;
1690 			zone_sectors = ti_limits.chunk_sectors;
1691 		}
1692 
1693 		/* Set I/O hints portion of queue limits */
1694 		if (ti->type->io_hints)
1695 			ti->type->io_hints(ti, &ti_limits);
1696 
1697 		/*
1698 		 * Check each device area is consistent with the target's
1699 		 * overall queue limits.
1700 		 */
1701 		if (ti->type->iterate_devices(ti, device_area_is_invalid,
1702 					      &ti_limits))
1703 			return -EINVAL;
1704 
1705 combine_limits:
1706 		/*
1707 		 * Merge this target's queue limits into the overall limits
1708 		 * for the table.
1709 		 */
1710 		if (blk_stack_limits(limits, &ti_limits, 0) < 0)
1711 			DMWARN("%s: adding target device "
1712 			       "(start sect %llu len %llu) "
1713 			       "caused an alignment inconsistency",
1714 			       dm_device_name(t->md),
1715 			       (unsigned long long) ti->begin,
1716 			       (unsigned long long) ti->len);
1717 	}
1718 
1719 	/*
1720 	 * Verify that the zoned model and zone sectors, as determined before
1721 	 * any .io_hints override, are the same across all devices in the table.
1722 	 * - this is especially relevant if .io_hints is emulating a disk-managed
1723 	 *   zoned model (aka BLK_ZONED_NONE) on host-managed zoned block devices.
1724 	 * BUT...
1725 	 */
1726 	if (limits->zoned != BLK_ZONED_NONE) {
1727 		/*
1728 		 * ...IF the above limits stacking determined a zoned model
1729 		 * validate that all of the table's devices conform to it.
1730 		 */
1731 		zoned_model = limits->zoned;
1732 		zone_sectors = limits->chunk_sectors;
1733 	}
1734 	if (validate_hardware_zoned_model(t, zoned_model, zone_sectors))
1735 		return -EINVAL;
1736 
1737 	return validate_hardware_logical_block_alignment(t, limits);
1738 }
1739 
1740 /*
1741  * Verify that all devices have an integrity profile that matches the
1742  * DM device's registered integrity profile.  If the profiles don't
1743  * match then unregister the DM device's integrity profile.
1744  */
dm_table_verify_integrity(struct dm_table * t)1745 static void dm_table_verify_integrity(struct dm_table *t)
1746 {
1747 	struct gendisk *template_disk = NULL;
1748 
1749 	if (t->integrity_added)
1750 		return;
1751 
1752 	if (t->integrity_supported) {
1753 		/*
1754 		 * Verify that the original integrity profile
1755 		 * matches all the devices in this table.
1756 		 */
1757 		template_disk = dm_table_get_integrity_disk(t);
1758 		if (template_disk &&
1759 		    blk_integrity_compare(dm_disk(t->md), template_disk) >= 0)
1760 			return;
1761 	}
1762 
1763 	if (integrity_profile_exists(dm_disk(t->md))) {
1764 		DMWARN("%s: unable to establish an integrity profile",
1765 		       dm_device_name(t->md));
1766 		blk_integrity_unregister(dm_disk(t->md));
1767 	}
1768 }
1769 
device_flush_capable(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)1770 static int device_flush_capable(struct dm_target *ti, struct dm_dev *dev,
1771 				sector_t start, sector_t len, void *data)
1772 {
1773 	unsigned long flush = (unsigned long) data;
1774 	struct request_queue *q = bdev_get_queue(dev->bdev);
1775 
1776 	return (q->queue_flags & flush);
1777 }
1778 
dm_table_supports_flush(struct dm_table * t,unsigned long flush)1779 static bool dm_table_supports_flush(struct dm_table *t, unsigned long flush)
1780 {
1781 	/*
1782 	 * Require at least one underlying device to support flushes.
1783 	 * t->devices includes internal dm devices such as mirror logs
1784 	 * so we need to use iterate_devices here, which targets
1785 	 * supporting flushes must provide.
1786 	 */
1787 	for (unsigned int i = 0; i < t->num_targets; i++) {
1788 		struct dm_target *ti = dm_table_get_target(t, i);
1789 
1790 		if (!ti->num_flush_bios)
1791 			continue;
1792 
1793 		if (ti->flush_supported)
1794 			return true;
1795 
1796 		if (ti->type->iterate_devices &&
1797 		    ti->type->iterate_devices(ti, device_flush_capable, (void *) flush))
1798 			return true;
1799 	}
1800 
1801 	return false;
1802 }
1803 
device_dax_write_cache_enabled(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)1804 static int device_dax_write_cache_enabled(struct dm_target *ti,
1805 					  struct dm_dev *dev, sector_t start,
1806 					  sector_t len, void *data)
1807 {
1808 	struct dax_device *dax_dev = dev->dax_dev;
1809 
1810 	if (!dax_dev)
1811 		return false;
1812 
1813 	if (dax_write_cache_enabled(dax_dev))
1814 		return true;
1815 	return false;
1816 }
1817 
device_is_rotational(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)1818 static int device_is_rotational(struct dm_target *ti, struct dm_dev *dev,
1819 				sector_t start, sector_t len, void *data)
1820 {
1821 	return !bdev_nonrot(dev->bdev);
1822 }
1823 
device_is_not_random(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)1824 static int device_is_not_random(struct dm_target *ti, struct dm_dev *dev,
1825 			     sector_t start, sector_t len, void *data)
1826 {
1827 	struct request_queue *q = bdev_get_queue(dev->bdev);
1828 
1829 	return !blk_queue_add_random(q);
1830 }
1831 
device_not_write_zeroes_capable(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)1832 static int device_not_write_zeroes_capable(struct dm_target *ti, struct dm_dev *dev,
1833 					   sector_t start, sector_t len, void *data)
1834 {
1835 	struct request_queue *q = bdev_get_queue(dev->bdev);
1836 
1837 	return !q->limits.max_write_zeroes_sectors;
1838 }
1839 
dm_table_supports_write_zeroes(struct dm_table * t)1840 static bool dm_table_supports_write_zeroes(struct dm_table *t)
1841 {
1842 	for (unsigned int i = 0; i < t->num_targets; i++) {
1843 		struct dm_target *ti = dm_table_get_target(t, i);
1844 
1845 		if (!ti->num_write_zeroes_bios)
1846 			return false;
1847 
1848 		if (!ti->type->iterate_devices ||
1849 		    ti->type->iterate_devices(ti, device_not_write_zeroes_capable, NULL))
1850 			return false;
1851 	}
1852 
1853 	return true;
1854 }
1855 
device_not_nowait_capable(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)1856 static int device_not_nowait_capable(struct dm_target *ti, struct dm_dev *dev,
1857 				     sector_t start, sector_t len, void *data)
1858 {
1859 	return !bdev_nowait(dev->bdev);
1860 }
1861 
dm_table_supports_nowait(struct dm_table * t)1862 static bool dm_table_supports_nowait(struct dm_table *t)
1863 {
1864 	for (unsigned int i = 0; i < t->num_targets; i++) {
1865 		struct dm_target *ti = dm_table_get_target(t, i);
1866 
1867 		if (!dm_target_supports_nowait(ti->type))
1868 			return false;
1869 
1870 		if (!ti->type->iterate_devices ||
1871 		    ti->type->iterate_devices(ti, device_not_nowait_capable, NULL))
1872 			return false;
1873 	}
1874 
1875 	return true;
1876 }
1877 
device_not_discard_capable(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)1878 static int device_not_discard_capable(struct dm_target *ti, struct dm_dev *dev,
1879 				      sector_t start, sector_t len, void *data)
1880 {
1881 	return !bdev_max_discard_sectors(dev->bdev);
1882 }
1883 
dm_table_supports_discards(struct dm_table * t)1884 static bool dm_table_supports_discards(struct dm_table *t)
1885 {
1886 	for (unsigned int i = 0; i < t->num_targets; i++) {
1887 		struct dm_target *ti = dm_table_get_target(t, i);
1888 
1889 		if (!ti->num_discard_bios)
1890 			return false;
1891 
1892 		/*
1893 		 * Either the target provides discard support (as implied by setting
1894 		 * 'discards_supported') or it relies on _all_ data devices having
1895 		 * discard support.
1896 		 */
1897 		if (!ti->discards_supported &&
1898 		    (!ti->type->iterate_devices ||
1899 		     ti->type->iterate_devices(ti, device_not_discard_capable, NULL)))
1900 			return false;
1901 	}
1902 
1903 	return true;
1904 }
1905 
device_not_secure_erase_capable(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)1906 static int device_not_secure_erase_capable(struct dm_target *ti,
1907 					   struct dm_dev *dev, sector_t start,
1908 					   sector_t len, void *data)
1909 {
1910 	return !bdev_max_secure_erase_sectors(dev->bdev);
1911 }
1912 
dm_table_supports_secure_erase(struct dm_table * t)1913 static bool dm_table_supports_secure_erase(struct dm_table *t)
1914 {
1915 	for (unsigned int i = 0; i < t->num_targets; i++) {
1916 		struct dm_target *ti = dm_table_get_target(t, i);
1917 
1918 		if (!ti->num_secure_erase_bios)
1919 			return false;
1920 
1921 		if (!ti->type->iterate_devices ||
1922 		    ti->type->iterate_devices(ti, device_not_secure_erase_capable, NULL))
1923 			return false;
1924 	}
1925 
1926 	return true;
1927 }
1928 
device_requires_stable_pages(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)1929 static int device_requires_stable_pages(struct dm_target *ti,
1930 					struct dm_dev *dev, sector_t start,
1931 					sector_t len, void *data)
1932 {
1933 	return bdev_stable_writes(dev->bdev);
1934 }
1935 
dm_table_set_restrictions(struct dm_table * t,struct request_queue * q,struct queue_limits * limits)1936 int dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
1937 			      struct queue_limits *limits)
1938 {
1939 	bool wc = false, fua = false;
1940 	int r;
1941 
1942 	/*
1943 	 * Copy table's limits to the DM device's request_queue
1944 	 */
1945 	q->limits = *limits;
1946 
1947 	if (dm_table_supports_nowait(t))
1948 		blk_queue_flag_set(QUEUE_FLAG_NOWAIT, q);
1949 	else
1950 		blk_queue_flag_clear(QUEUE_FLAG_NOWAIT, q);
1951 
1952 	if (!dm_table_supports_discards(t)) {
1953 		q->limits.max_discard_sectors = 0;
1954 		q->limits.max_hw_discard_sectors = 0;
1955 		q->limits.discard_granularity = 0;
1956 		q->limits.discard_alignment = 0;
1957 		q->limits.discard_misaligned = 0;
1958 	}
1959 
1960 	if (!dm_table_supports_secure_erase(t))
1961 		q->limits.max_secure_erase_sectors = 0;
1962 
1963 	if (dm_table_supports_flush(t, (1UL << QUEUE_FLAG_WC))) {
1964 		wc = true;
1965 		if (dm_table_supports_flush(t, (1UL << QUEUE_FLAG_FUA)))
1966 			fua = true;
1967 	}
1968 	blk_queue_write_cache(q, wc, fua);
1969 
1970 	if (dm_table_supports_dax(t, device_not_dax_capable)) {
1971 		blk_queue_flag_set(QUEUE_FLAG_DAX, q);
1972 		if (dm_table_supports_dax(t, device_not_dax_synchronous_capable))
1973 			set_dax_synchronous(t->md->dax_dev);
1974 	}
1975 	else
1976 		blk_queue_flag_clear(QUEUE_FLAG_DAX, q);
1977 
1978 	if (dm_table_any_dev_attr(t, device_dax_write_cache_enabled, NULL))
1979 		dax_write_cache(t->md->dax_dev, true);
1980 
1981 	/* Ensure that all underlying devices are non-rotational. */
1982 	if (dm_table_any_dev_attr(t, device_is_rotational, NULL))
1983 		blk_queue_flag_clear(QUEUE_FLAG_NONROT, q);
1984 	else
1985 		blk_queue_flag_set(QUEUE_FLAG_NONROT, q);
1986 
1987 	if (!dm_table_supports_write_zeroes(t))
1988 		q->limits.max_write_zeroes_sectors = 0;
1989 
1990 	dm_table_verify_integrity(t);
1991 
1992 	/*
1993 	 * Some devices don't use blk_integrity but still want stable pages
1994 	 * because they do their own checksumming.
1995 	 * If any underlying device requires stable pages, a table must require
1996 	 * them as well.  Only targets that support iterate_devices are considered:
1997 	 * don't want error, zero, etc to require stable pages.
1998 	 */
1999 	if (dm_table_any_dev_attr(t, device_requires_stable_pages, NULL))
2000 		blk_queue_flag_set(QUEUE_FLAG_STABLE_WRITES, q);
2001 	else
2002 		blk_queue_flag_clear(QUEUE_FLAG_STABLE_WRITES, q);
2003 
2004 	/*
2005 	 * Determine whether or not this queue's I/O timings contribute
2006 	 * to the entropy pool, Only request-based targets use this.
2007 	 * Clear QUEUE_FLAG_ADD_RANDOM if any underlying device does not
2008 	 * have it set.
2009 	 */
2010 	if (blk_queue_add_random(q) &&
2011 	    dm_table_any_dev_attr(t, device_is_not_random, NULL))
2012 		blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, q);
2013 
2014 	/*
2015 	 * For a zoned target, setup the zones related queue attributes
2016 	 * and resources necessary for zone append emulation if necessary.
2017 	 */
2018 	if (blk_queue_is_zoned(q)) {
2019 		r = dm_set_zones_restrictions(t, q);
2020 		if (r)
2021 			return r;
2022 		if (!static_key_enabled(&zoned_enabled.key))
2023 			static_branch_enable(&zoned_enabled);
2024 	}
2025 
2026 	dm_update_crypto_profile(q, t);
2027 	disk_update_readahead(t->md->disk);
2028 
2029 	/*
2030 	 * Check for request-based device is left to
2031 	 * dm_mq_init_request_queue()->blk_mq_init_allocated_queue().
2032 	 *
2033 	 * For bio-based device, only set QUEUE_FLAG_POLL when all
2034 	 * underlying devices supporting polling.
2035 	 */
2036 	if (__table_type_bio_based(t->type)) {
2037 		if (dm_table_supports_poll(t))
2038 			blk_queue_flag_set(QUEUE_FLAG_POLL, q);
2039 		else
2040 			blk_queue_flag_clear(QUEUE_FLAG_POLL, q);
2041 	}
2042 
2043 	return 0;
2044 }
2045 
dm_table_get_devices(struct dm_table * t)2046 struct list_head *dm_table_get_devices(struct dm_table *t)
2047 {
2048 	return &t->devices;
2049 }
2050 
dm_table_get_mode(struct dm_table * t)2051 fmode_t dm_table_get_mode(struct dm_table *t)
2052 {
2053 	return t->mode;
2054 }
2055 EXPORT_SYMBOL(dm_table_get_mode);
2056 
2057 enum suspend_mode {
2058 	PRESUSPEND,
2059 	PRESUSPEND_UNDO,
2060 	POSTSUSPEND,
2061 };
2062 
suspend_targets(struct dm_table * t,enum suspend_mode mode)2063 static void suspend_targets(struct dm_table *t, enum suspend_mode mode)
2064 {
2065 	lockdep_assert_held(&t->md->suspend_lock);
2066 
2067 	for (unsigned int i = 0; i < t->num_targets; i++) {
2068 		struct dm_target *ti = dm_table_get_target(t, i);
2069 
2070 		switch (mode) {
2071 		case PRESUSPEND:
2072 			if (ti->type->presuspend)
2073 				ti->type->presuspend(ti);
2074 			break;
2075 		case PRESUSPEND_UNDO:
2076 			if (ti->type->presuspend_undo)
2077 				ti->type->presuspend_undo(ti);
2078 			break;
2079 		case POSTSUSPEND:
2080 			if (ti->type->postsuspend)
2081 				ti->type->postsuspend(ti);
2082 			break;
2083 		}
2084 	}
2085 }
2086 
dm_table_presuspend_targets(struct dm_table * t)2087 void dm_table_presuspend_targets(struct dm_table *t)
2088 {
2089 	if (!t)
2090 		return;
2091 
2092 	suspend_targets(t, PRESUSPEND);
2093 }
2094 
dm_table_presuspend_undo_targets(struct dm_table * t)2095 void dm_table_presuspend_undo_targets(struct dm_table *t)
2096 {
2097 	if (!t)
2098 		return;
2099 
2100 	suspend_targets(t, PRESUSPEND_UNDO);
2101 }
2102 
dm_table_postsuspend_targets(struct dm_table * t)2103 void dm_table_postsuspend_targets(struct dm_table *t)
2104 {
2105 	if (!t)
2106 		return;
2107 
2108 	suspend_targets(t, POSTSUSPEND);
2109 }
2110 
dm_table_resume_targets(struct dm_table * t)2111 int dm_table_resume_targets(struct dm_table *t)
2112 {
2113 	unsigned int i;
2114 	int r = 0;
2115 
2116 	lockdep_assert_held(&t->md->suspend_lock);
2117 
2118 	for (i = 0; i < t->num_targets; i++) {
2119 		struct dm_target *ti = dm_table_get_target(t, i);
2120 
2121 		if (!ti->type->preresume)
2122 			continue;
2123 
2124 		r = ti->type->preresume(ti);
2125 		if (r) {
2126 			DMERR("%s: %s: preresume failed, error = %d",
2127 			      dm_device_name(t->md), ti->type->name, r);
2128 			return r;
2129 		}
2130 	}
2131 
2132 	for (i = 0; i < t->num_targets; i++) {
2133 		struct dm_target *ti = dm_table_get_target(t, i);
2134 
2135 		if (ti->type->resume)
2136 			ti->type->resume(ti);
2137 	}
2138 
2139 	return 0;
2140 }
2141 
dm_table_get_md(struct dm_table * t)2142 struct mapped_device *dm_table_get_md(struct dm_table *t)
2143 {
2144 	return t->md;
2145 }
2146 EXPORT_SYMBOL(dm_table_get_md);
2147 
dm_table_device_name(struct dm_table * t)2148 const char *dm_table_device_name(struct dm_table *t)
2149 {
2150 	return dm_device_name(t->md);
2151 }
2152 EXPORT_SYMBOL_GPL(dm_table_device_name);
2153 
dm_table_run_md_queue_async(struct dm_table * t)2154 void dm_table_run_md_queue_async(struct dm_table *t)
2155 {
2156 	if (!dm_table_request_based(t))
2157 		return;
2158 
2159 	if (t->md->queue)
2160 		blk_mq_run_hw_queues(t->md->queue, true);
2161 }
2162 EXPORT_SYMBOL(dm_table_run_md_queue_async);
2163 
2164