1  // SPDX-License-Identifier: GPL-2.0-only
2  /*
3   * Copyright (C) 2001 Sistina Software (UK) Limited.
4   * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
5   *
6   * This file is released under the GPL.
7   */
8  
9  #include "dm-core.h"
10  #include "dm-rq.h"
11  
12  #include <linux/module.h>
13  #include <linux/vmalloc.h>
14  #include <linux/blkdev.h>
15  #include <linux/blk-integrity.h>
16  #include <linux/namei.h>
17  #include <linux/ctype.h>
18  #include <linux/string.h>
19  #include <linux/slab.h>
20  #include <linux/interrupt.h>
21  #include <linux/mutex.h>
22  #include <linux/delay.h>
23  #include <linux/atomic.h>
24  #include <linux/blk-mq.h>
25  #include <linux/mount.h>
26  #include <linux/dax.h>
27  
28  #define DM_MSG_PREFIX "table"
29  
30  #define NODE_SIZE L1_CACHE_BYTES
31  #define KEYS_PER_NODE (NODE_SIZE / sizeof(sector_t))
32  #define CHILDREN_PER_NODE (KEYS_PER_NODE + 1)
33  
34  /*
35   * Similar to ceiling(log_size(n))
36   */
int_log(unsigned int n,unsigned int base)37  static unsigned int int_log(unsigned int n, unsigned int base)
38  {
39  	int result = 0;
40  
41  	while (n > 1) {
42  		n = dm_div_up(n, base);
43  		result++;
44  	}
45  
46  	return result;
47  }
48  
49  /*
50   * Calculate the index of the child node of the n'th node k'th key.
51   */
get_child(unsigned int n,unsigned int k)52  static inline unsigned int get_child(unsigned int n, unsigned int k)
53  {
54  	return (n * CHILDREN_PER_NODE) + k;
55  }
56  
57  /*
58   * Return the n'th node of level l from table t.
59   */
get_node(struct dm_table * t,unsigned int l,unsigned int n)60  static inline sector_t *get_node(struct dm_table *t,
61  				 unsigned int l, unsigned int n)
62  {
63  	return t->index[l] + (n * KEYS_PER_NODE);
64  }
65  
66  /*
67   * Return the highest key that you could lookup from the n'th
68   * node on level l of the btree.
69   */
high(struct dm_table * t,unsigned int l,unsigned int n)70  static sector_t high(struct dm_table *t, unsigned int l, unsigned int n)
71  {
72  	for (; l < t->depth - 1; l++)
73  		n = get_child(n, CHILDREN_PER_NODE - 1);
74  
75  	if (n >= t->counts[l])
76  		return (sector_t) -1;
77  
78  	return get_node(t, l, n)[KEYS_PER_NODE - 1];
79  }
80  
81  /*
82   * Fills in a level of the btree based on the highs of the level
83   * below it.
84   */
setup_btree_index(unsigned int l,struct dm_table * t)85  static int setup_btree_index(unsigned int l, struct dm_table *t)
86  {
87  	unsigned int n, k;
88  	sector_t *node;
89  
90  	for (n = 0U; n < t->counts[l]; n++) {
91  		node = get_node(t, l, n);
92  
93  		for (k = 0U; k < KEYS_PER_NODE; k++)
94  			node[k] = high(t, l + 1, get_child(n, k));
95  	}
96  
97  	return 0;
98  }
99  
100  /*
101   * highs, and targets are managed as dynamic arrays during a
102   * table load.
103   */
alloc_targets(struct dm_table * t,unsigned int num)104  static int alloc_targets(struct dm_table *t, unsigned int num)
105  {
106  	sector_t *n_highs;
107  	struct dm_target *n_targets;
108  
109  	/*
110  	 * Allocate both the target array and offset array at once.
111  	 */
112  	n_highs = kvcalloc(num, sizeof(struct dm_target) + sizeof(sector_t),
113  			   GFP_KERNEL);
114  	if (!n_highs)
115  		return -ENOMEM;
116  
117  	n_targets = (struct dm_target *) (n_highs + num);
118  
119  	memset(n_highs, -1, sizeof(*n_highs) * num);
120  	kvfree(t->highs);
121  
122  	t->num_allocated = num;
123  	t->highs = n_highs;
124  	t->targets = n_targets;
125  
126  	return 0;
127  }
128  
dm_table_create(struct dm_table ** result,blk_mode_t mode,unsigned int num_targets,struct mapped_device * md)129  int dm_table_create(struct dm_table **result, blk_mode_t mode,
130  		    unsigned int num_targets, struct mapped_device *md)
131  {
132  	struct dm_table *t;
133  
134  	if (num_targets > DM_MAX_TARGETS)
135  		return -EOVERFLOW;
136  
137  	t = kzalloc(sizeof(*t), GFP_KERNEL);
138  
139  	if (!t)
140  		return -ENOMEM;
141  
142  	INIT_LIST_HEAD(&t->devices);
143  	init_rwsem(&t->devices_lock);
144  
145  	if (!num_targets)
146  		num_targets = KEYS_PER_NODE;
147  
148  	num_targets = dm_round_up(num_targets, KEYS_PER_NODE);
149  
150  	if (!num_targets) {
151  		kfree(t);
152  		return -EOVERFLOW;
153  	}
154  
155  	if (alloc_targets(t, num_targets)) {
156  		kfree(t);
157  		return -ENOMEM;
158  	}
159  
160  	t->type = DM_TYPE_NONE;
161  	t->mode = mode;
162  	t->md = md;
163  	t->flush_bypasses_map = true;
164  	*result = t;
165  	return 0;
166  }
167  
free_devices(struct list_head * devices,struct mapped_device * md)168  static void free_devices(struct list_head *devices, struct mapped_device *md)
169  {
170  	struct list_head *tmp, *next;
171  
172  	list_for_each_safe(tmp, next, devices) {
173  		struct dm_dev_internal *dd =
174  		    list_entry(tmp, struct dm_dev_internal, list);
175  		DMWARN("%s: dm_table_destroy: dm_put_device call missing for %s",
176  		       dm_device_name(md), dd->dm_dev->name);
177  		dm_put_table_device(md, dd->dm_dev);
178  		kfree(dd);
179  	}
180  }
181  
182  static void dm_table_destroy_crypto_profile(struct dm_table *t);
183  
dm_table_destroy(struct dm_table * t)184  void dm_table_destroy(struct dm_table *t)
185  {
186  	if (!t)
187  		return;
188  
189  	/* free the indexes */
190  	if (t->depth >= 2)
191  		kvfree(t->index[t->depth - 2]);
192  
193  	/* free the targets */
194  	for (unsigned int i = 0; i < t->num_targets; i++) {
195  		struct dm_target *ti = dm_table_get_target(t, i);
196  
197  		if (ti->type->dtr)
198  			ti->type->dtr(ti);
199  
200  		dm_put_target_type(ti->type);
201  	}
202  
203  	kvfree(t->highs);
204  
205  	/* free the device list */
206  	free_devices(&t->devices, t->md);
207  
208  	dm_free_md_mempools(t->mempools);
209  
210  	dm_table_destroy_crypto_profile(t);
211  
212  	kfree(t);
213  }
214  
215  /*
216   * See if we've already got a device in the list.
217   */
find_device(struct list_head * l,dev_t dev)218  static struct dm_dev_internal *find_device(struct list_head *l, dev_t dev)
219  {
220  	struct dm_dev_internal *dd;
221  
222  	list_for_each_entry(dd, l, list)
223  		if (dd->dm_dev->bdev->bd_dev == dev)
224  			return dd;
225  
226  	return NULL;
227  }
228  
229  /*
230   * If possible, this checks an area of a destination device is invalid.
231   */
device_area_is_invalid(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)232  static int device_area_is_invalid(struct dm_target *ti, struct dm_dev *dev,
233  				  sector_t start, sector_t len, void *data)
234  {
235  	struct queue_limits *limits = data;
236  	struct block_device *bdev = dev->bdev;
237  	sector_t dev_size = bdev_nr_sectors(bdev);
238  	unsigned short logical_block_size_sectors =
239  		limits->logical_block_size >> SECTOR_SHIFT;
240  
241  	if (!dev_size)
242  		return 0;
243  
244  	if ((start >= dev_size) || (start + len > dev_size)) {
245  		DMERR("%s: %pg too small for target: start=%llu, len=%llu, dev_size=%llu",
246  		      dm_device_name(ti->table->md), bdev,
247  		      (unsigned long long)start,
248  		      (unsigned long long)len,
249  		      (unsigned long long)dev_size);
250  		return 1;
251  	}
252  
253  	/*
254  	 * If the target is mapped to zoned block device(s), check
255  	 * that the zones are not partially mapped.
256  	 */
257  	if (bdev_is_zoned(bdev)) {
258  		unsigned int zone_sectors = bdev_zone_sectors(bdev);
259  
260  		if (start & (zone_sectors - 1)) {
261  			DMERR("%s: start=%llu not aligned to h/w zone size %u of %pg",
262  			      dm_device_name(ti->table->md),
263  			      (unsigned long long)start,
264  			      zone_sectors, bdev);
265  			return 1;
266  		}
267  
268  		/*
269  		 * Note: The last zone of a zoned block device may be smaller
270  		 * than other zones. So for a target mapping the end of a
271  		 * zoned block device with such a zone, len would not be zone
272  		 * aligned. We do not allow such last smaller zone to be part
273  		 * of the mapping here to ensure that mappings with multiple
274  		 * devices do not end up with a smaller zone in the middle of
275  		 * the sector range.
276  		 */
277  		if (len & (zone_sectors - 1)) {
278  			DMERR("%s: len=%llu not aligned to h/w zone size %u of %pg",
279  			      dm_device_name(ti->table->md),
280  			      (unsigned long long)len,
281  			      zone_sectors, bdev);
282  			return 1;
283  		}
284  	}
285  
286  	if (logical_block_size_sectors <= 1)
287  		return 0;
288  
289  	if (start & (logical_block_size_sectors - 1)) {
290  		DMERR("%s: start=%llu not aligned to h/w logical block size %u of %pg",
291  		      dm_device_name(ti->table->md),
292  		      (unsigned long long)start,
293  		      limits->logical_block_size, bdev);
294  		return 1;
295  	}
296  
297  	if (len & (logical_block_size_sectors - 1)) {
298  		DMERR("%s: len=%llu not aligned to h/w logical block size %u of %pg",
299  		      dm_device_name(ti->table->md),
300  		      (unsigned long long)len,
301  		      limits->logical_block_size, bdev);
302  		return 1;
303  	}
304  
305  	return 0;
306  }
307  
308  /*
309   * This upgrades the mode on an already open dm_dev, being
310   * careful to leave things as they were if we fail to reopen the
311   * device and not to touch the existing bdev field in case
312   * it is accessed concurrently.
313   */
upgrade_mode(struct dm_dev_internal * dd,blk_mode_t new_mode,struct mapped_device * md)314  static int upgrade_mode(struct dm_dev_internal *dd, blk_mode_t new_mode,
315  			struct mapped_device *md)
316  {
317  	int r;
318  	struct dm_dev *old_dev, *new_dev;
319  
320  	old_dev = dd->dm_dev;
321  
322  	r = dm_get_table_device(md, dd->dm_dev->bdev->bd_dev,
323  				dd->dm_dev->mode | new_mode, &new_dev);
324  	if (r)
325  		return r;
326  
327  	dd->dm_dev = new_dev;
328  	dm_put_table_device(md, old_dev);
329  
330  	return 0;
331  }
332  
333  /*
334   * Note: the __ref annotation is because this function can call the __init
335   * marked early_lookup_bdev when called during early boot code from dm-init.c.
336   */
dm_devt_from_path(const char * path,dev_t * dev_p)337  int __ref dm_devt_from_path(const char *path, dev_t *dev_p)
338  {
339  	int r;
340  	dev_t dev;
341  	unsigned int major, minor;
342  	char dummy;
343  
344  	if (sscanf(path, "%u:%u%c", &major, &minor, &dummy) == 2) {
345  		/* Extract the major/minor numbers */
346  		dev = MKDEV(major, minor);
347  		if (MAJOR(dev) != major || MINOR(dev) != minor)
348  			return -EOVERFLOW;
349  	} else {
350  		r = lookup_bdev(path, &dev);
351  #ifndef MODULE
352  		if (r && system_state < SYSTEM_RUNNING)
353  			r = early_lookup_bdev(path, &dev);
354  #endif
355  		if (r)
356  			return r;
357  	}
358  	*dev_p = dev;
359  	return 0;
360  }
361  EXPORT_SYMBOL(dm_devt_from_path);
362  
363  /*
364   * Add a device to the list, or just increment the usage count if
365   * it's already present.
366   */
dm_get_device(struct dm_target * ti,const char * path,blk_mode_t mode,struct dm_dev ** result)367  int dm_get_device(struct dm_target *ti, const char *path, blk_mode_t mode,
368  		  struct dm_dev **result)
369  {
370  	int r;
371  	dev_t dev;
372  	struct dm_dev_internal *dd;
373  	struct dm_table *t = ti->table;
374  
375  	BUG_ON(!t);
376  
377  	r = dm_devt_from_path(path, &dev);
378  	if (r)
379  		return r;
380  
381  	if (dev == disk_devt(t->md->disk))
382  		return -EINVAL;
383  
384  	down_write(&t->devices_lock);
385  
386  	dd = find_device(&t->devices, dev);
387  	if (!dd) {
388  		dd = kmalloc(sizeof(*dd), GFP_KERNEL);
389  		if (!dd) {
390  			r = -ENOMEM;
391  			goto unlock_ret_r;
392  		}
393  
394  		r = dm_get_table_device(t->md, dev, mode, &dd->dm_dev);
395  		if (r) {
396  			kfree(dd);
397  			goto unlock_ret_r;
398  		}
399  
400  		refcount_set(&dd->count, 1);
401  		list_add(&dd->list, &t->devices);
402  		goto out;
403  
404  	} else if (dd->dm_dev->mode != (mode | dd->dm_dev->mode)) {
405  		r = upgrade_mode(dd, mode, t->md);
406  		if (r)
407  			goto unlock_ret_r;
408  	}
409  	refcount_inc(&dd->count);
410  out:
411  	up_write(&t->devices_lock);
412  	*result = dd->dm_dev;
413  	return 0;
414  
415  unlock_ret_r:
416  	up_write(&t->devices_lock);
417  	return r;
418  }
419  EXPORT_SYMBOL(dm_get_device);
420  
dm_set_device_limits(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)421  static int dm_set_device_limits(struct dm_target *ti, struct dm_dev *dev,
422  				sector_t start, sector_t len, void *data)
423  {
424  	struct queue_limits *limits = data;
425  	struct block_device *bdev = dev->bdev;
426  	struct request_queue *q = bdev_get_queue(bdev);
427  
428  	if (unlikely(!q)) {
429  		DMWARN("%s: Cannot set limits for nonexistent device %pg",
430  		       dm_device_name(ti->table->md), bdev);
431  		return 0;
432  	}
433  
434  	if (blk_stack_limits(limits, &q->limits,
435  			get_start_sect(bdev) + start) < 0)
436  		DMWARN("%s: adding target device %pg caused an alignment inconsistency: "
437  		       "physical_block_size=%u, logical_block_size=%u, "
438  		       "alignment_offset=%u, start=%llu",
439  		       dm_device_name(ti->table->md), bdev,
440  		       q->limits.physical_block_size,
441  		       q->limits.logical_block_size,
442  		       q->limits.alignment_offset,
443  		       (unsigned long long) start << SECTOR_SHIFT);
444  
445  	/*
446  	 * Only stack the integrity profile if the target doesn't have native
447  	 * integrity support.
448  	 */
449  	if (!dm_target_has_integrity(ti->type))
450  		queue_limits_stack_integrity_bdev(limits, bdev);
451  	return 0;
452  }
453  
454  /*
455   * Decrement a device's use count and remove it if necessary.
456   */
dm_put_device(struct dm_target * ti,struct dm_dev * d)457  void dm_put_device(struct dm_target *ti, struct dm_dev *d)
458  {
459  	int found = 0;
460  	struct dm_table *t = ti->table;
461  	struct list_head *devices = &t->devices;
462  	struct dm_dev_internal *dd;
463  
464  	down_write(&t->devices_lock);
465  
466  	list_for_each_entry(dd, devices, list) {
467  		if (dd->dm_dev == d) {
468  			found = 1;
469  			break;
470  		}
471  	}
472  	if (!found) {
473  		DMERR("%s: device %s not in table devices list",
474  		      dm_device_name(t->md), d->name);
475  		goto unlock_ret;
476  	}
477  	if (refcount_dec_and_test(&dd->count)) {
478  		dm_put_table_device(t->md, d);
479  		list_del(&dd->list);
480  		kfree(dd);
481  	}
482  
483  unlock_ret:
484  	up_write(&t->devices_lock);
485  }
486  EXPORT_SYMBOL(dm_put_device);
487  
488  /*
489   * Checks to see if the target joins onto the end of the table.
490   */
adjoin(struct dm_table * t,struct dm_target * ti)491  static int adjoin(struct dm_table *t, struct dm_target *ti)
492  {
493  	struct dm_target *prev;
494  
495  	if (!t->num_targets)
496  		return !ti->begin;
497  
498  	prev = &t->targets[t->num_targets - 1];
499  	return (ti->begin == (prev->begin + prev->len));
500  }
501  
502  /*
503   * Used to dynamically allocate the arg array.
504   *
505   * We do first allocation with GFP_NOIO because dm-mpath and dm-thin must
506   * process messages even if some device is suspended. These messages have a
507   * small fixed number of arguments.
508   *
509   * On the other hand, dm-switch needs to process bulk data using messages and
510   * excessive use of GFP_NOIO could cause trouble.
511   */
realloc_argv(unsigned int * size,char ** old_argv)512  static char **realloc_argv(unsigned int *size, char **old_argv)
513  {
514  	char **argv;
515  	unsigned int new_size;
516  	gfp_t gfp;
517  
518  	if (*size) {
519  		new_size = *size * 2;
520  		gfp = GFP_KERNEL;
521  	} else {
522  		new_size = 8;
523  		gfp = GFP_NOIO;
524  	}
525  	argv = kmalloc_array(new_size, sizeof(*argv), gfp);
526  	if (argv && old_argv) {
527  		memcpy(argv, old_argv, *size * sizeof(*argv));
528  		*size = new_size;
529  	}
530  
531  	kfree(old_argv);
532  	return argv;
533  }
534  
535  /*
536   * Destructively splits up the argument list to pass to ctr.
537   */
dm_split_args(int * argc,char *** argvp,char * input)538  int dm_split_args(int *argc, char ***argvp, char *input)
539  {
540  	char *start, *end = input, *out, **argv = NULL;
541  	unsigned int array_size = 0;
542  
543  	*argc = 0;
544  
545  	if (!input) {
546  		*argvp = NULL;
547  		return 0;
548  	}
549  
550  	argv = realloc_argv(&array_size, argv);
551  	if (!argv)
552  		return -ENOMEM;
553  
554  	while (1) {
555  		/* Skip whitespace */
556  		start = skip_spaces(end);
557  
558  		if (!*start)
559  			break;	/* success, we hit the end */
560  
561  		/* 'out' is used to remove any back-quotes */
562  		end = out = start;
563  		while (*end) {
564  			/* Everything apart from '\0' can be quoted */
565  			if (*end == '\\' && *(end + 1)) {
566  				*out++ = *(end + 1);
567  				end += 2;
568  				continue;
569  			}
570  
571  			if (isspace(*end))
572  				break;	/* end of token */
573  
574  			*out++ = *end++;
575  		}
576  
577  		/* have we already filled the array ? */
578  		if ((*argc + 1) > array_size) {
579  			argv = realloc_argv(&array_size, argv);
580  			if (!argv)
581  				return -ENOMEM;
582  		}
583  
584  		/* we know this is whitespace */
585  		if (*end)
586  			end++;
587  
588  		/* terminate the string and put it in the array */
589  		*out = '\0';
590  		argv[*argc] = start;
591  		(*argc)++;
592  	}
593  
594  	*argvp = argv;
595  	return 0;
596  }
597  
dm_set_stacking_limits(struct queue_limits * limits)598  static void dm_set_stacking_limits(struct queue_limits *limits)
599  {
600  	blk_set_stacking_limits(limits);
601  	limits->features |= BLK_FEAT_IO_STAT | BLK_FEAT_NOWAIT | BLK_FEAT_POLL;
602  }
603  
604  /*
605   * Impose necessary and sufficient conditions on a devices's table such
606   * that any incoming bio which respects its logical_block_size can be
607   * processed successfully.  If it falls across the boundary between
608   * two or more targets, the size of each piece it gets split into must
609   * be compatible with the logical_block_size of the target processing it.
610   */
validate_hardware_logical_block_alignment(struct dm_table * t,struct queue_limits * limits)611  static int validate_hardware_logical_block_alignment(struct dm_table *t,
612  						     struct queue_limits *limits)
613  {
614  	/*
615  	 * This function uses arithmetic modulo the logical_block_size
616  	 * (in units of 512-byte sectors).
617  	 */
618  	unsigned short device_logical_block_size_sects =
619  		limits->logical_block_size >> SECTOR_SHIFT;
620  
621  	/*
622  	 * Offset of the start of the next table entry, mod logical_block_size.
623  	 */
624  	unsigned short next_target_start = 0;
625  
626  	/*
627  	 * Given an aligned bio that extends beyond the end of a
628  	 * target, how many sectors must the next target handle?
629  	 */
630  	unsigned short remaining = 0;
631  
632  	struct dm_target *ti;
633  	struct queue_limits ti_limits;
634  	unsigned int i;
635  
636  	/*
637  	 * Check each entry in the table in turn.
638  	 */
639  	for (i = 0; i < t->num_targets; i++) {
640  		ti = dm_table_get_target(t, i);
641  
642  		dm_set_stacking_limits(&ti_limits);
643  
644  		/* combine all target devices' limits */
645  		if (ti->type->iterate_devices)
646  			ti->type->iterate_devices(ti, dm_set_device_limits,
647  						  &ti_limits);
648  
649  		/*
650  		 * If the remaining sectors fall entirely within this
651  		 * table entry are they compatible with its logical_block_size?
652  		 */
653  		if (remaining < ti->len &&
654  		    remaining & ((ti_limits.logical_block_size >>
655  				  SECTOR_SHIFT) - 1))
656  			break;	/* Error */
657  
658  		next_target_start =
659  		    (unsigned short) ((next_target_start + ti->len) &
660  				      (device_logical_block_size_sects - 1));
661  		remaining = next_target_start ?
662  		    device_logical_block_size_sects - next_target_start : 0;
663  	}
664  
665  	if (remaining) {
666  		DMERR("%s: table line %u (start sect %llu len %llu) "
667  		      "not aligned to h/w logical block size %u",
668  		      dm_device_name(t->md), i,
669  		      (unsigned long long) ti->begin,
670  		      (unsigned long long) ti->len,
671  		      limits->logical_block_size);
672  		return -EINVAL;
673  	}
674  
675  	return 0;
676  }
677  
dm_table_add_target(struct dm_table * t,const char * type,sector_t start,sector_t len,char * params)678  int dm_table_add_target(struct dm_table *t, const char *type,
679  			sector_t start, sector_t len, char *params)
680  {
681  	int r = -EINVAL, argc;
682  	char **argv;
683  	struct dm_target *ti;
684  
685  	if (t->singleton) {
686  		DMERR("%s: target type %s must appear alone in table",
687  		      dm_device_name(t->md), t->targets->type->name);
688  		return -EINVAL;
689  	}
690  
691  	BUG_ON(t->num_targets >= t->num_allocated);
692  
693  	ti = t->targets + t->num_targets;
694  	memset(ti, 0, sizeof(*ti));
695  
696  	if (!len) {
697  		DMERR("%s: zero-length target", dm_device_name(t->md));
698  		return -EINVAL;
699  	}
700  
701  	ti->type = dm_get_target_type(type);
702  	if (!ti->type) {
703  		DMERR("%s: %s: unknown target type", dm_device_name(t->md), type);
704  		return -EINVAL;
705  	}
706  
707  	if (dm_target_needs_singleton(ti->type)) {
708  		if (t->num_targets) {
709  			ti->error = "singleton target type must appear alone in table";
710  			goto bad;
711  		}
712  		t->singleton = true;
713  	}
714  
715  	if (dm_target_always_writeable(ti->type) &&
716  	    !(t->mode & BLK_OPEN_WRITE)) {
717  		ti->error = "target type may not be included in a read-only table";
718  		goto bad;
719  	}
720  
721  	if (t->immutable_target_type) {
722  		if (t->immutable_target_type != ti->type) {
723  			ti->error = "immutable target type cannot be mixed with other target types";
724  			goto bad;
725  		}
726  	} else if (dm_target_is_immutable(ti->type)) {
727  		if (t->num_targets) {
728  			ti->error = "immutable target type cannot be mixed with other target types";
729  			goto bad;
730  		}
731  		t->immutable_target_type = ti->type;
732  	}
733  
734  	ti->table = t;
735  	ti->begin = start;
736  	ti->len = len;
737  	ti->error = "Unknown error";
738  
739  	/*
740  	 * Does this target adjoin the previous one ?
741  	 */
742  	if (!adjoin(t, ti)) {
743  		ti->error = "Gap in table";
744  		goto bad;
745  	}
746  
747  	r = dm_split_args(&argc, &argv, params);
748  	if (r) {
749  		ti->error = "couldn't split parameters";
750  		goto bad;
751  	}
752  
753  	r = ti->type->ctr(ti, argc, argv);
754  	kfree(argv);
755  	if (r)
756  		goto bad;
757  
758  	t->highs[t->num_targets++] = ti->begin + ti->len - 1;
759  
760  	if (!ti->num_discard_bios && ti->discards_supported)
761  		DMWARN("%s: %s: ignoring discards_supported because num_discard_bios is zero.",
762  		       dm_device_name(t->md), type);
763  
764  	if (ti->limit_swap_bios && !static_key_enabled(&swap_bios_enabled.key))
765  		static_branch_enable(&swap_bios_enabled);
766  
767  	if (!ti->flush_bypasses_map)
768  		t->flush_bypasses_map = false;
769  
770  	return 0;
771  
772   bad:
773  	DMERR("%s: %s: %s (%pe)", dm_device_name(t->md), type, ti->error, ERR_PTR(r));
774  	dm_put_target_type(ti->type);
775  	return r;
776  }
777  
778  /*
779   * Target argument parsing helpers.
780   */
validate_next_arg(const struct dm_arg * arg,struct dm_arg_set * arg_set,unsigned int * value,char ** error,unsigned int grouped)781  static int validate_next_arg(const struct dm_arg *arg, struct dm_arg_set *arg_set,
782  			     unsigned int *value, char **error, unsigned int grouped)
783  {
784  	const char *arg_str = dm_shift_arg(arg_set);
785  	char dummy;
786  
787  	if (!arg_str ||
788  	    (sscanf(arg_str, "%u%c", value, &dummy) != 1) ||
789  	    (*value < arg->min) ||
790  	    (*value > arg->max) ||
791  	    (grouped && arg_set->argc < *value)) {
792  		*error = arg->error;
793  		return -EINVAL;
794  	}
795  
796  	return 0;
797  }
798  
dm_read_arg(const struct dm_arg * arg,struct dm_arg_set * arg_set,unsigned int * value,char ** error)799  int dm_read_arg(const struct dm_arg *arg, struct dm_arg_set *arg_set,
800  		unsigned int *value, char **error)
801  {
802  	return validate_next_arg(arg, arg_set, value, error, 0);
803  }
804  EXPORT_SYMBOL(dm_read_arg);
805  
dm_read_arg_group(const struct dm_arg * arg,struct dm_arg_set * arg_set,unsigned int * value,char ** error)806  int dm_read_arg_group(const struct dm_arg *arg, struct dm_arg_set *arg_set,
807  		      unsigned int *value, char **error)
808  {
809  	return validate_next_arg(arg, arg_set, value, error, 1);
810  }
811  EXPORT_SYMBOL(dm_read_arg_group);
812  
dm_shift_arg(struct dm_arg_set * as)813  const char *dm_shift_arg(struct dm_arg_set *as)
814  {
815  	char *r;
816  
817  	if (as->argc) {
818  		as->argc--;
819  		r = *as->argv;
820  		as->argv++;
821  		return r;
822  	}
823  
824  	return NULL;
825  }
826  EXPORT_SYMBOL(dm_shift_arg);
827  
dm_consume_args(struct dm_arg_set * as,unsigned int num_args)828  void dm_consume_args(struct dm_arg_set *as, unsigned int num_args)
829  {
830  	BUG_ON(as->argc < num_args);
831  	as->argc -= num_args;
832  	as->argv += num_args;
833  }
834  EXPORT_SYMBOL(dm_consume_args);
835  
__table_type_bio_based(enum dm_queue_mode table_type)836  static bool __table_type_bio_based(enum dm_queue_mode table_type)
837  {
838  	return (table_type == DM_TYPE_BIO_BASED ||
839  		table_type == DM_TYPE_DAX_BIO_BASED);
840  }
841  
__table_type_request_based(enum dm_queue_mode table_type)842  static bool __table_type_request_based(enum dm_queue_mode table_type)
843  {
844  	return table_type == DM_TYPE_REQUEST_BASED;
845  }
846  
dm_table_set_type(struct dm_table * t,enum dm_queue_mode type)847  void dm_table_set_type(struct dm_table *t, enum dm_queue_mode type)
848  {
849  	t->type = type;
850  }
851  EXPORT_SYMBOL_GPL(dm_table_set_type);
852  
853  /* 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)854  static int device_not_dax_capable(struct dm_target *ti, struct dm_dev *dev,
855  			sector_t start, sector_t len, void *data)
856  {
857  	if (dev->dax_dev)
858  		return false;
859  
860  	DMDEBUG("%pg: error: dax unsupported by block device", dev->bdev);
861  	return true;
862  }
863  
864  /* 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)865  static int device_not_dax_synchronous_capable(struct dm_target *ti, struct dm_dev *dev,
866  					      sector_t start, sector_t len, void *data)
867  {
868  	return !dev->dax_dev || !dax_synchronous(dev->dax_dev);
869  }
870  
dm_table_supports_dax(struct dm_table * t,iterate_devices_callout_fn iterate_fn)871  static bool dm_table_supports_dax(struct dm_table *t,
872  				  iterate_devices_callout_fn iterate_fn)
873  {
874  	/* Ensure that all targets support DAX. */
875  	for (unsigned int i = 0; i < t->num_targets; i++) {
876  		struct dm_target *ti = dm_table_get_target(t, i);
877  
878  		if (!ti->type->direct_access)
879  			return false;
880  
881  		if (dm_target_is_wildcard(ti->type) ||
882  		    !ti->type->iterate_devices ||
883  		    ti->type->iterate_devices(ti, iterate_fn, NULL))
884  			return false;
885  	}
886  
887  	return true;
888  }
889  
device_is_rq_stackable(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)890  static int device_is_rq_stackable(struct dm_target *ti, struct dm_dev *dev,
891  				  sector_t start, sector_t len, void *data)
892  {
893  	struct block_device *bdev = dev->bdev;
894  	struct request_queue *q = bdev_get_queue(bdev);
895  
896  	/* request-based cannot stack on partitions! */
897  	if (bdev_is_partition(bdev))
898  		return false;
899  
900  	return queue_is_mq(q);
901  }
902  
dm_table_determine_type(struct dm_table * t)903  static int dm_table_determine_type(struct dm_table *t)
904  {
905  	unsigned int bio_based = 0, request_based = 0, hybrid = 0;
906  	struct dm_target *ti;
907  	struct list_head *devices = dm_table_get_devices(t);
908  	enum dm_queue_mode live_md_type = dm_get_md_type(t->md);
909  
910  	if (t->type != DM_TYPE_NONE) {
911  		/* target already set the table's type */
912  		if (t->type == DM_TYPE_BIO_BASED) {
913  			/* possibly upgrade to a variant of bio-based */
914  			goto verify_bio_based;
915  		}
916  		BUG_ON(t->type == DM_TYPE_DAX_BIO_BASED);
917  		goto verify_rq_based;
918  	}
919  
920  	for (unsigned int i = 0; i < t->num_targets; i++) {
921  		ti = dm_table_get_target(t, i);
922  		if (dm_target_hybrid(ti))
923  			hybrid = 1;
924  		else if (dm_target_request_based(ti))
925  			request_based = 1;
926  		else
927  			bio_based = 1;
928  
929  		if (bio_based && request_based) {
930  			DMERR("Inconsistent table: different target types can't be mixed up");
931  			return -EINVAL;
932  		}
933  	}
934  
935  	if (hybrid && !bio_based && !request_based) {
936  		/*
937  		 * The targets can work either way.
938  		 * Determine the type from the live device.
939  		 * Default to bio-based if device is new.
940  		 */
941  		if (__table_type_request_based(live_md_type))
942  			request_based = 1;
943  		else
944  			bio_based = 1;
945  	}
946  
947  	if (bio_based) {
948  verify_bio_based:
949  		/* We must use this table as bio-based */
950  		t->type = DM_TYPE_BIO_BASED;
951  		if (dm_table_supports_dax(t, device_not_dax_capable) ||
952  		    (list_empty(devices) && live_md_type == DM_TYPE_DAX_BIO_BASED)) {
953  			t->type = DM_TYPE_DAX_BIO_BASED;
954  		}
955  		return 0;
956  	}
957  
958  	BUG_ON(!request_based); /* No targets in this table */
959  
960  	t->type = DM_TYPE_REQUEST_BASED;
961  
962  verify_rq_based:
963  	/*
964  	 * Request-based dm supports only tables that have a single target now.
965  	 * To support multiple targets, request splitting support is needed,
966  	 * and that needs lots of changes in the block-layer.
967  	 * (e.g. request completion process for partial completion.)
968  	 */
969  	if (t->num_targets > 1) {
970  		DMERR("request-based DM doesn't support multiple targets");
971  		return -EINVAL;
972  	}
973  
974  	if (list_empty(devices)) {
975  		int srcu_idx;
976  		struct dm_table *live_table = dm_get_live_table(t->md, &srcu_idx);
977  
978  		/* inherit live table's type */
979  		if (live_table)
980  			t->type = live_table->type;
981  		dm_put_live_table(t->md, srcu_idx);
982  		return 0;
983  	}
984  
985  	ti = dm_table_get_immutable_target(t);
986  	if (!ti) {
987  		DMERR("table load rejected: immutable target is required");
988  		return -EINVAL;
989  	} else if (ti->max_io_len) {
990  		DMERR("table load rejected: immutable target that splits IO is not supported");
991  		return -EINVAL;
992  	}
993  
994  	/* Non-request-stackable devices can't be used for request-based dm */
995  	if (!ti->type->iterate_devices ||
996  	    !ti->type->iterate_devices(ti, device_is_rq_stackable, NULL)) {
997  		DMERR("table load rejected: including non-request-stackable devices");
998  		return -EINVAL;
999  	}
1000  
1001  	return 0;
1002  }
1003  
dm_table_get_type(struct dm_table * t)1004  enum dm_queue_mode dm_table_get_type(struct dm_table *t)
1005  {
1006  	return t->type;
1007  }
1008  
dm_table_get_immutable_target_type(struct dm_table * t)1009  struct target_type *dm_table_get_immutable_target_type(struct dm_table *t)
1010  {
1011  	return t->immutable_target_type;
1012  }
1013  
dm_table_get_immutable_target(struct dm_table * t)1014  struct dm_target *dm_table_get_immutable_target(struct dm_table *t)
1015  {
1016  	/* Immutable target is implicitly a singleton */
1017  	if (t->num_targets > 1 ||
1018  	    !dm_target_is_immutable(t->targets[0].type))
1019  		return NULL;
1020  
1021  	return t->targets;
1022  }
1023  
dm_table_get_wildcard_target(struct dm_table * t)1024  struct dm_target *dm_table_get_wildcard_target(struct dm_table *t)
1025  {
1026  	for (unsigned int i = 0; i < t->num_targets; i++) {
1027  		struct dm_target *ti = dm_table_get_target(t, i);
1028  
1029  		if (dm_target_is_wildcard(ti->type))
1030  			return ti;
1031  	}
1032  
1033  	return NULL;
1034  }
1035  
dm_table_bio_based(struct dm_table * t)1036  bool dm_table_bio_based(struct dm_table *t)
1037  {
1038  	return __table_type_bio_based(dm_table_get_type(t));
1039  }
1040  
dm_table_request_based(struct dm_table * t)1041  bool dm_table_request_based(struct dm_table *t)
1042  {
1043  	return __table_type_request_based(dm_table_get_type(t));
1044  }
1045  
dm_table_alloc_md_mempools(struct dm_table * t,struct mapped_device * md)1046  static int dm_table_alloc_md_mempools(struct dm_table *t, struct mapped_device *md)
1047  {
1048  	enum dm_queue_mode type = dm_table_get_type(t);
1049  	unsigned int per_io_data_size = 0, front_pad, io_front_pad;
1050  	unsigned int min_pool_size = 0, pool_size;
1051  	struct dm_md_mempools *pools;
1052  	unsigned int bioset_flags = 0;
1053  	bool mempool_needs_integrity = t->integrity_supported;
1054  
1055  	if (unlikely(type == DM_TYPE_NONE)) {
1056  		DMERR("no table type is set, can't allocate mempools");
1057  		return -EINVAL;
1058  	}
1059  
1060  	pools = kzalloc_node(sizeof(*pools), GFP_KERNEL, md->numa_node_id);
1061  	if (!pools)
1062  		return -ENOMEM;
1063  
1064  	if (type == DM_TYPE_REQUEST_BASED) {
1065  		pool_size = dm_get_reserved_rq_based_ios();
1066  		front_pad = offsetof(struct dm_rq_clone_bio_info, clone);
1067  		goto init_bs;
1068  	}
1069  
1070  	if (md->queue->limits.features & BLK_FEAT_POLL)
1071  		bioset_flags |= BIOSET_PERCPU_CACHE;
1072  
1073  	for (unsigned int i = 0; i < t->num_targets; i++) {
1074  		struct dm_target *ti = dm_table_get_target(t, i);
1075  
1076  		per_io_data_size = max(per_io_data_size, ti->per_io_data_size);
1077  		min_pool_size = max(min_pool_size, ti->num_flush_bios);
1078  
1079  		mempool_needs_integrity |= ti->mempool_needs_integrity;
1080  	}
1081  	pool_size = max(dm_get_reserved_bio_based_ios(), min_pool_size);
1082  	front_pad = roundup(per_io_data_size,
1083  		__alignof__(struct dm_target_io)) + DM_TARGET_IO_BIO_OFFSET;
1084  
1085  	io_front_pad = roundup(per_io_data_size,
1086  		__alignof__(struct dm_io)) + DM_IO_BIO_OFFSET;
1087  	if (bioset_init(&pools->io_bs, pool_size, io_front_pad, bioset_flags))
1088  		goto out_free_pools;
1089  	if (mempool_needs_integrity &&
1090  	    bioset_integrity_create(&pools->io_bs, pool_size))
1091  		goto out_free_pools;
1092  init_bs:
1093  	if (bioset_init(&pools->bs, pool_size, front_pad, 0))
1094  		goto out_free_pools;
1095  	if (mempool_needs_integrity &&
1096  	    bioset_integrity_create(&pools->bs, pool_size))
1097  		goto out_free_pools;
1098  
1099  	t->mempools = pools;
1100  	return 0;
1101  
1102  out_free_pools:
1103  	dm_free_md_mempools(pools);
1104  	return -ENOMEM;
1105  }
1106  
setup_indexes(struct dm_table * t)1107  static int setup_indexes(struct dm_table *t)
1108  {
1109  	int i;
1110  	unsigned int total = 0;
1111  	sector_t *indexes;
1112  
1113  	/* allocate the space for *all* the indexes */
1114  	for (i = t->depth - 2; i >= 0; i--) {
1115  		t->counts[i] = dm_div_up(t->counts[i + 1], CHILDREN_PER_NODE);
1116  		total += t->counts[i];
1117  	}
1118  
1119  	indexes = kvcalloc(total, NODE_SIZE, GFP_KERNEL);
1120  	if (!indexes)
1121  		return -ENOMEM;
1122  
1123  	/* set up internal nodes, bottom-up */
1124  	for (i = t->depth - 2; i >= 0; i--) {
1125  		t->index[i] = indexes;
1126  		indexes += (KEYS_PER_NODE * t->counts[i]);
1127  		setup_btree_index(i, t);
1128  	}
1129  
1130  	return 0;
1131  }
1132  
1133  /*
1134   * Builds the btree to index the map.
1135   */
dm_table_build_index(struct dm_table * t)1136  static int dm_table_build_index(struct dm_table *t)
1137  {
1138  	int r = 0;
1139  	unsigned int leaf_nodes;
1140  
1141  	/* how many indexes will the btree have ? */
1142  	leaf_nodes = dm_div_up(t->num_targets, KEYS_PER_NODE);
1143  	t->depth = 1 + int_log(leaf_nodes, CHILDREN_PER_NODE);
1144  
1145  	/* leaf layer has already been set up */
1146  	t->counts[t->depth - 1] = leaf_nodes;
1147  	t->index[t->depth - 1] = t->highs;
1148  
1149  	if (t->depth >= 2)
1150  		r = setup_indexes(t);
1151  
1152  	return r;
1153  }
1154  
1155  #ifdef CONFIG_BLK_INLINE_ENCRYPTION
1156  
1157  struct dm_crypto_profile {
1158  	struct blk_crypto_profile profile;
1159  	struct mapped_device *md;
1160  };
1161  
dm_keyslot_evict_callback(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)1162  static int dm_keyslot_evict_callback(struct dm_target *ti, struct dm_dev *dev,
1163  				     sector_t start, sector_t len, void *data)
1164  {
1165  	const struct blk_crypto_key *key = data;
1166  
1167  	blk_crypto_evict_key(dev->bdev, key);
1168  	return 0;
1169  }
1170  
1171  /*
1172   * When an inline encryption key is evicted from a device-mapper device, evict
1173   * it from all the underlying devices.
1174   */
dm_keyslot_evict(struct blk_crypto_profile * profile,const struct blk_crypto_key * key,unsigned int slot)1175  static int dm_keyslot_evict(struct blk_crypto_profile *profile,
1176  			    const struct blk_crypto_key *key, unsigned int slot)
1177  {
1178  	struct mapped_device *md =
1179  		container_of(profile, struct dm_crypto_profile, profile)->md;
1180  	struct dm_table *t;
1181  	int srcu_idx;
1182  
1183  	t = dm_get_live_table(md, &srcu_idx);
1184  	if (!t)
1185  		return 0;
1186  
1187  	for (unsigned int i = 0; i < t->num_targets; i++) {
1188  		struct dm_target *ti = dm_table_get_target(t, i);
1189  
1190  		if (!ti->type->iterate_devices)
1191  			continue;
1192  		ti->type->iterate_devices(ti, dm_keyslot_evict_callback,
1193  					  (void *)key);
1194  	}
1195  
1196  	dm_put_live_table(md, srcu_idx);
1197  	return 0;
1198  }
1199  
1200  static int
device_intersect_crypto_capabilities(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)1201  device_intersect_crypto_capabilities(struct dm_target *ti, struct dm_dev *dev,
1202  				     sector_t start, sector_t len, void *data)
1203  {
1204  	struct blk_crypto_profile *parent = data;
1205  	struct blk_crypto_profile *child =
1206  		bdev_get_queue(dev->bdev)->crypto_profile;
1207  
1208  	blk_crypto_intersect_capabilities(parent, child);
1209  	return 0;
1210  }
1211  
dm_destroy_crypto_profile(struct blk_crypto_profile * profile)1212  void dm_destroy_crypto_profile(struct blk_crypto_profile *profile)
1213  {
1214  	struct dm_crypto_profile *dmcp = container_of(profile,
1215  						      struct dm_crypto_profile,
1216  						      profile);
1217  
1218  	if (!profile)
1219  		return;
1220  
1221  	blk_crypto_profile_destroy(profile);
1222  	kfree(dmcp);
1223  }
1224  
dm_table_destroy_crypto_profile(struct dm_table * t)1225  static void dm_table_destroy_crypto_profile(struct dm_table *t)
1226  {
1227  	dm_destroy_crypto_profile(t->crypto_profile);
1228  	t->crypto_profile = NULL;
1229  }
1230  
1231  /*
1232   * Constructs and initializes t->crypto_profile with a crypto profile that
1233   * represents the common set of crypto capabilities of the devices described by
1234   * the dm_table.  However, if the constructed crypto profile doesn't support all
1235   * crypto capabilities that are supported by the current mapped_device, it
1236   * returns an error instead, since we don't support removing crypto capabilities
1237   * on table changes.  Finally, if the constructed crypto profile is "empty" (has
1238   * no crypto capabilities at all), it just sets t->crypto_profile to NULL.
1239   */
dm_table_construct_crypto_profile(struct dm_table * t)1240  static int dm_table_construct_crypto_profile(struct dm_table *t)
1241  {
1242  	struct dm_crypto_profile *dmcp;
1243  	struct blk_crypto_profile *profile;
1244  	unsigned int i;
1245  	bool empty_profile = true;
1246  
1247  	dmcp = kmalloc(sizeof(*dmcp), GFP_KERNEL);
1248  	if (!dmcp)
1249  		return -ENOMEM;
1250  	dmcp->md = t->md;
1251  
1252  	profile = &dmcp->profile;
1253  	blk_crypto_profile_init(profile, 0);
1254  	profile->ll_ops.keyslot_evict = dm_keyslot_evict;
1255  	profile->max_dun_bytes_supported = UINT_MAX;
1256  	memset(profile->modes_supported, 0xFF,
1257  	       sizeof(profile->modes_supported));
1258  
1259  	for (i = 0; i < t->num_targets; i++) {
1260  		struct dm_target *ti = dm_table_get_target(t, i);
1261  
1262  		if (!dm_target_passes_crypto(ti->type)) {
1263  			blk_crypto_intersect_capabilities(profile, NULL);
1264  			break;
1265  		}
1266  		if (!ti->type->iterate_devices)
1267  			continue;
1268  		ti->type->iterate_devices(ti,
1269  					  device_intersect_crypto_capabilities,
1270  					  profile);
1271  	}
1272  
1273  	if (t->md->queue &&
1274  	    !blk_crypto_has_capabilities(profile,
1275  					 t->md->queue->crypto_profile)) {
1276  		DMERR("Inline encryption capabilities of new DM table were more restrictive than the old table's. This is not supported!");
1277  		dm_destroy_crypto_profile(profile);
1278  		return -EINVAL;
1279  	}
1280  
1281  	/*
1282  	 * If the new profile doesn't actually support any crypto capabilities,
1283  	 * we may as well represent it with a NULL profile.
1284  	 */
1285  	for (i = 0; i < ARRAY_SIZE(profile->modes_supported); i++) {
1286  		if (profile->modes_supported[i]) {
1287  			empty_profile = false;
1288  			break;
1289  		}
1290  	}
1291  
1292  	if (empty_profile) {
1293  		dm_destroy_crypto_profile(profile);
1294  		profile = NULL;
1295  	}
1296  
1297  	/*
1298  	 * t->crypto_profile is only set temporarily while the table is being
1299  	 * set up, and it gets set to NULL after the profile has been
1300  	 * transferred to the request_queue.
1301  	 */
1302  	t->crypto_profile = profile;
1303  
1304  	return 0;
1305  }
1306  
dm_update_crypto_profile(struct request_queue * q,struct dm_table * t)1307  static void dm_update_crypto_profile(struct request_queue *q,
1308  				     struct dm_table *t)
1309  {
1310  	if (!t->crypto_profile)
1311  		return;
1312  
1313  	/* Make the crypto profile less restrictive. */
1314  	if (!q->crypto_profile) {
1315  		blk_crypto_register(t->crypto_profile, q);
1316  	} else {
1317  		blk_crypto_update_capabilities(q->crypto_profile,
1318  					       t->crypto_profile);
1319  		dm_destroy_crypto_profile(t->crypto_profile);
1320  	}
1321  	t->crypto_profile = NULL;
1322  }
1323  
1324  #else /* CONFIG_BLK_INLINE_ENCRYPTION */
1325  
dm_table_construct_crypto_profile(struct dm_table * t)1326  static int dm_table_construct_crypto_profile(struct dm_table *t)
1327  {
1328  	return 0;
1329  }
1330  
dm_destroy_crypto_profile(struct blk_crypto_profile * profile)1331  void dm_destroy_crypto_profile(struct blk_crypto_profile *profile)
1332  {
1333  }
1334  
dm_table_destroy_crypto_profile(struct dm_table * t)1335  static void dm_table_destroy_crypto_profile(struct dm_table *t)
1336  {
1337  }
1338  
dm_update_crypto_profile(struct request_queue * q,struct dm_table * t)1339  static void dm_update_crypto_profile(struct request_queue *q,
1340  				     struct dm_table *t)
1341  {
1342  }
1343  
1344  #endif /* !CONFIG_BLK_INLINE_ENCRYPTION */
1345  
1346  /*
1347   * Prepares the table for use by building the indices,
1348   * setting the type, and allocating mempools.
1349   */
dm_table_complete(struct dm_table * t)1350  int dm_table_complete(struct dm_table *t)
1351  {
1352  	int r;
1353  
1354  	r = dm_table_determine_type(t);
1355  	if (r) {
1356  		DMERR("unable to determine table type");
1357  		return r;
1358  	}
1359  
1360  	r = dm_table_build_index(t);
1361  	if (r) {
1362  		DMERR("unable to build btrees");
1363  		return r;
1364  	}
1365  
1366  	r = dm_table_construct_crypto_profile(t);
1367  	if (r) {
1368  		DMERR("could not construct crypto profile.");
1369  		return r;
1370  	}
1371  
1372  	r = dm_table_alloc_md_mempools(t, t->md);
1373  	if (r)
1374  		DMERR("unable to allocate mempools");
1375  
1376  	return r;
1377  }
1378  
1379  static DEFINE_MUTEX(_event_lock);
dm_table_event_callback(struct dm_table * t,void (* fn)(void *),void * context)1380  void dm_table_event_callback(struct dm_table *t,
1381  			     void (*fn)(void *), void *context)
1382  {
1383  	mutex_lock(&_event_lock);
1384  	t->event_fn = fn;
1385  	t->event_context = context;
1386  	mutex_unlock(&_event_lock);
1387  }
1388  
dm_table_event(struct dm_table * t)1389  void dm_table_event(struct dm_table *t)
1390  {
1391  	mutex_lock(&_event_lock);
1392  	if (t->event_fn)
1393  		t->event_fn(t->event_context);
1394  	mutex_unlock(&_event_lock);
1395  }
1396  EXPORT_SYMBOL(dm_table_event);
1397  
dm_table_get_size(struct dm_table * t)1398  inline sector_t dm_table_get_size(struct dm_table *t)
1399  {
1400  	return t->num_targets ? (t->highs[t->num_targets - 1] + 1) : 0;
1401  }
1402  EXPORT_SYMBOL(dm_table_get_size);
1403  
1404  /*
1405   * Search the btree for the correct target.
1406   *
1407   * Caller should check returned pointer for NULL
1408   * to trap I/O beyond end of device.
1409   */
dm_table_find_target(struct dm_table * t,sector_t sector)1410  struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector)
1411  {
1412  	unsigned int l, n = 0, k = 0;
1413  	sector_t *node;
1414  
1415  	if (unlikely(sector >= dm_table_get_size(t)))
1416  		return NULL;
1417  
1418  	for (l = 0; l < t->depth; l++) {
1419  		n = get_child(n, k);
1420  		node = get_node(t, l, n);
1421  
1422  		for (k = 0; k < KEYS_PER_NODE; k++)
1423  			if (node[k] >= sector)
1424  				break;
1425  	}
1426  
1427  	return &t->targets[(KEYS_PER_NODE * n) + k];
1428  }
1429  
1430  /*
1431   * type->iterate_devices() should be called when the sanity check needs to
1432   * iterate and check all underlying data devices. iterate_devices() will
1433   * iterate all underlying data devices until it encounters a non-zero return
1434   * code, returned by whether the input iterate_devices_callout_fn, or
1435   * iterate_devices() itself internally.
1436   *
1437   * For some target type (e.g. dm-stripe), one call of iterate_devices() may
1438   * iterate multiple underlying devices internally, in which case a non-zero
1439   * return code returned by iterate_devices_callout_fn will stop the iteration
1440   * in advance.
1441   *
1442   * Cases requiring _any_ underlying device supporting some kind of attribute,
1443   * should use the iteration structure like dm_table_any_dev_attr(), or call
1444   * it directly. @func should handle semantics of positive examples, e.g.
1445   * capable of something.
1446   *
1447   * Cases requiring _all_ underlying devices supporting some kind of attribute,
1448   * should use the iteration structure like dm_table_supports_nowait() or
1449   * dm_table_supports_discards(). Or introduce dm_table_all_devs_attr() that
1450   * uses an @anti_func that handle semantics of counter examples, e.g. not
1451   * capable of something. So: return !dm_table_any_dev_attr(t, anti_func, data);
1452   */
dm_table_any_dev_attr(struct dm_table * t,iterate_devices_callout_fn func,void * data)1453  static bool dm_table_any_dev_attr(struct dm_table *t,
1454  				  iterate_devices_callout_fn func, void *data)
1455  {
1456  	for (unsigned int i = 0; i < t->num_targets; i++) {
1457  		struct dm_target *ti = dm_table_get_target(t, i);
1458  
1459  		if (ti->type->iterate_devices &&
1460  		    ti->type->iterate_devices(ti, func, data))
1461  			return true;
1462  	}
1463  
1464  	return false;
1465  }
1466  
count_device(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)1467  static int count_device(struct dm_target *ti, struct dm_dev *dev,
1468  			sector_t start, sector_t len, void *data)
1469  {
1470  	unsigned int *num_devices = data;
1471  
1472  	(*num_devices)++;
1473  
1474  	return 0;
1475  }
1476  
1477  /*
1478   * Check whether a table has no data devices attached using each
1479   * target's iterate_devices method.
1480   * Returns false if the result is unknown because a target doesn't
1481   * support iterate_devices.
1482   */
dm_table_has_no_data_devices(struct dm_table * t)1483  bool dm_table_has_no_data_devices(struct dm_table *t)
1484  {
1485  	for (unsigned int i = 0; i < t->num_targets; i++) {
1486  		struct dm_target *ti = dm_table_get_target(t, i);
1487  		unsigned int num_devices = 0;
1488  
1489  		if (!ti->type->iterate_devices)
1490  			return false;
1491  
1492  		ti->type->iterate_devices(ti, count_device, &num_devices);
1493  		if (num_devices)
1494  			return false;
1495  	}
1496  
1497  	return true;
1498  }
1499  
device_not_zoned(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)1500  static int device_not_zoned(struct dm_target *ti, struct dm_dev *dev,
1501  			    sector_t start, sector_t len, void *data)
1502  {
1503  	bool *zoned = data;
1504  
1505  	return bdev_is_zoned(dev->bdev) != *zoned;
1506  }
1507  
device_is_zoned_model(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)1508  static int device_is_zoned_model(struct dm_target *ti, struct dm_dev *dev,
1509  				 sector_t start, sector_t len, void *data)
1510  {
1511  	return bdev_is_zoned(dev->bdev);
1512  }
1513  
1514  /*
1515   * Check the device zoned model based on the target feature flag. If the target
1516   * has the DM_TARGET_ZONED_HM feature flag set, host-managed zoned devices are
1517   * also accepted but all devices must have the same zoned model. If the target
1518   * has the DM_TARGET_MIXED_ZONED_MODEL feature set, the devices can have any
1519   * zoned model with all zoned devices having the same zone size.
1520   */
dm_table_supports_zoned(struct dm_table * t,bool zoned)1521  static bool dm_table_supports_zoned(struct dm_table *t, bool zoned)
1522  {
1523  	for (unsigned int i = 0; i < t->num_targets; i++) {
1524  		struct dm_target *ti = dm_table_get_target(t, i);
1525  
1526  		/*
1527  		 * For the wildcard target (dm-error), if we do not have a
1528  		 * backing device, we must always return false. If we have a
1529  		 * backing device, the result must depend on checking zoned
1530  		 * model, like for any other target. So for this, check directly
1531  		 * if the target backing device is zoned as we get "false" when
1532  		 * dm-error was set without a backing device.
1533  		 */
1534  		if (dm_target_is_wildcard(ti->type) &&
1535  		    !ti->type->iterate_devices(ti, device_is_zoned_model, NULL))
1536  			return false;
1537  
1538  		if (dm_target_supports_zoned_hm(ti->type)) {
1539  			if (!ti->type->iterate_devices ||
1540  			    ti->type->iterate_devices(ti, device_not_zoned,
1541  						      &zoned))
1542  				return false;
1543  		} else if (!dm_target_supports_mixed_zoned_model(ti->type)) {
1544  			if (zoned)
1545  				return false;
1546  		}
1547  	}
1548  
1549  	return true;
1550  }
1551  
device_not_matches_zone_sectors(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)1552  static int device_not_matches_zone_sectors(struct dm_target *ti, struct dm_dev *dev,
1553  					   sector_t start, sector_t len, void *data)
1554  {
1555  	unsigned int *zone_sectors = data;
1556  
1557  	if (!bdev_is_zoned(dev->bdev))
1558  		return 0;
1559  	return bdev_zone_sectors(dev->bdev) != *zone_sectors;
1560  }
1561  
1562  /*
1563   * Check consistency of zoned model and zone sectors across all targets. For
1564   * zone sectors, if the destination device is a zoned block device, it shall
1565   * have the specified zone_sectors.
1566   */
validate_hardware_zoned(struct dm_table * t,bool zoned,unsigned int zone_sectors)1567  static int validate_hardware_zoned(struct dm_table *t, bool zoned,
1568  				   unsigned int zone_sectors)
1569  {
1570  	if (!zoned)
1571  		return 0;
1572  
1573  	if (!dm_table_supports_zoned(t, zoned)) {
1574  		DMERR("%s: zoned model is not consistent across all devices",
1575  		      dm_device_name(t->md));
1576  		return -EINVAL;
1577  	}
1578  
1579  	/* Check zone size validity and compatibility */
1580  	if (!zone_sectors || !is_power_of_2(zone_sectors))
1581  		return -EINVAL;
1582  
1583  	if (dm_table_any_dev_attr(t, device_not_matches_zone_sectors, &zone_sectors)) {
1584  		DMERR("%s: zone sectors is not consistent across all zoned devices",
1585  		      dm_device_name(t->md));
1586  		return -EINVAL;
1587  	}
1588  
1589  	return 0;
1590  }
1591  
1592  /*
1593   * Establish the new table's queue_limits and validate them.
1594   */
dm_calculate_queue_limits(struct dm_table * t,struct queue_limits * limits)1595  int dm_calculate_queue_limits(struct dm_table *t,
1596  			      struct queue_limits *limits)
1597  {
1598  	struct queue_limits ti_limits;
1599  	unsigned int zone_sectors = 0;
1600  	bool zoned = false;
1601  
1602  	dm_set_stacking_limits(limits);
1603  
1604  	t->integrity_supported = true;
1605  	for (unsigned int i = 0; i < t->num_targets; i++) {
1606  		struct dm_target *ti = dm_table_get_target(t, i);
1607  
1608  		if (!dm_target_passes_integrity(ti->type))
1609  			t->integrity_supported = false;
1610  	}
1611  
1612  	for (unsigned int i = 0; i < t->num_targets; i++) {
1613  		struct dm_target *ti = dm_table_get_target(t, i);
1614  
1615  		dm_set_stacking_limits(&ti_limits);
1616  
1617  		if (!ti->type->iterate_devices) {
1618  			/* Set I/O hints portion of queue limits */
1619  			if (ti->type->io_hints)
1620  				ti->type->io_hints(ti, &ti_limits);
1621  			goto combine_limits;
1622  		}
1623  
1624  		/*
1625  		 * Combine queue limits of all the devices this target uses.
1626  		 */
1627  		ti->type->iterate_devices(ti, dm_set_device_limits,
1628  					  &ti_limits);
1629  
1630  		if (!zoned && (ti_limits.features & BLK_FEAT_ZONED)) {
1631  			/*
1632  			 * After stacking all limits, validate all devices
1633  			 * in table support this zoned model and zone sectors.
1634  			 */
1635  			zoned = (ti_limits.features & BLK_FEAT_ZONED);
1636  			zone_sectors = ti_limits.chunk_sectors;
1637  		}
1638  
1639  		/* Set I/O hints portion of queue limits */
1640  		if (ti->type->io_hints)
1641  			ti->type->io_hints(ti, &ti_limits);
1642  
1643  		/*
1644  		 * Check each device area is consistent with the target's
1645  		 * overall queue limits.
1646  		 */
1647  		if (ti->type->iterate_devices(ti, device_area_is_invalid,
1648  					      &ti_limits))
1649  			return -EINVAL;
1650  
1651  combine_limits:
1652  		/*
1653  		 * Merge this target's queue limits into the overall limits
1654  		 * for the table.
1655  		 */
1656  		if (blk_stack_limits(limits, &ti_limits, 0) < 0)
1657  			DMWARN("%s: adding target device (start sect %llu len %llu) "
1658  			       "caused an alignment inconsistency",
1659  			       dm_device_name(t->md),
1660  			       (unsigned long long) ti->begin,
1661  			       (unsigned long long) ti->len);
1662  
1663  		if (t->integrity_supported ||
1664  		    dm_target_has_integrity(ti->type)) {
1665  			if (!queue_limits_stack_integrity(limits, &ti_limits)) {
1666  				DMWARN("%s: adding target device (start sect %llu len %llu) "
1667  				       "disabled integrity support due to incompatibility",
1668  				       dm_device_name(t->md),
1669  				       (unsigned long long) ti->begin,
1670  				       (unsigned long long) ti->len);
1671  				t->integrity_supported = false;
1672  			}
1673  		}
1674  	}
1675  
1676  	/*
1677  	 * Verify that the zoned model and zone sectors, as determined before
1678  	 * any .io_hints override, are the same across all devices in the table.
1679  	 * - this is especially relevant if .io_hints is emulating a disk-managed
1680  	 *   zoned model on host-managed zoned block devices.
1681  	 * BUT...
1682  	 */
1683  	if (limits->features & BLK_FEAT_ZONED) {
1684  		/*
1685  		 * ...IF the above limits stacking determined a zoned model
1686  		 * validate that all of the table's devices conform to it.
1687  		 */
1688  		zoned = limits->features & BLK_FEAT_ZONED;
1689  		zone_sectors = limits->chunk_sectors;
1690  	}
1691  	if (validate_hardware_zoned(t, zoned, zone_sectors))
1692  		return -EINVAL;
1693  
1694  	return validate_hardware_logical_block_alignment(t, limits);
1695  }
1696  
1697  /*
1698   * Check if a target requires flush support even if none of the underlying
1699   * devices need it (e.g. to persist target-specific metadata).
1700   */
dm_table_supports_flush(struct dm_table * t)1701  static bool dm_table_supports_flush(struct dm_table *t)
1702  {
1703  	for (unsigned int i = 0; i < t->num_targets; i++) {
1704  		struct dm_target *ti = dm_table_get_target(t, i);
1705  
1706  		if (ti->num_flush_bios && ti->flush_supported)
1707  			return true;
1708  	}
1709  
1710  	return false;
1711  }
1712  
device_dax_write_cache_enabled(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)1713  static int device_dax_write_cache_enabled(struct dm_target *ti,
1714  					  struct dm_dev *dev, sector_t start,
1715  					  sector_t len, void *data)
1716  {
1717  	struct dax_device *dax_dev = dev->dax_dev;
1718  
1719  	if (!dax_dev)
1720  		return false;
1721  
1722  	if (dax_write_cache_enabled(dax_dev))
1723  		return true;
1724  	return false;
1725  }
1726  
device_not_write_zeroes_capable(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)1727  static int device_not_write_zeroes_capable(struct dm_target *ti, struct dm_dev *dev,
1728  					   sector_t start, sector_t len, void *data)
1729  {
1730  	struct request_queue *q = bdev_get_queue(dev->bdev);
1731  
1732  	return !q->limits.max_write_zeroes_sectors;
1733  }
1734  
dm_table_supports_write_zeroes(struct dm_table * t)1735  static bool dm_table_supports_write_zeroes(struct dm_table *t)
1736  {
1737  	for (unsigned int i = 0; i < t->num_targets; i++) {
1738  		struct dm_target *ti = dm_table_get_target(t, i);
1739  
1740  		if (!ti->num_write_zeroes_bios)
1741  			return false;
1742  
1743  		if (!ti->type->iterate_devices ||
1744  		    ti->type->iterate_devices(ti, device_not_write_zeroes_capable, NULL))
1745  			return false;
1746  	}
1747  
1748  	return true;
1749  }
1750  
dm_table_supports_nowait(struct dm_table * t)1751  static bool dm_table_supports_nowait(struct dm_table *t)
1752  {
1753  	for (unsigned int i = 0; i < t->num_targets; i++) {
1754  		struct dm_target *ti = dm_table_get_target(t, i);
1755  
1756  		if (!dm_target_supports_nowait(ti->type))
1757  			return false;
1758  	}
1759  
1760  	return true;
1761  }
1762  
device_not_discard_capable(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)1763  static int device_not_discard_capable(struct dm_target *ti, struct dm_dev *dev,
1764  				      sector_t start, sector_t len, void *data)
1765  {
1766  	return !bdev_max_discard_sectors(dev->bdev);
1767  }
1768  
dm_table_supports_discards(struct dm_table * t)1769  static bool dm_table_supports_discards(struct dm_table *t)
1770  {
1771  	for (unsigned int i = 0; i < t->num_targets; i++) {
1772  		struct dm_target *ti = dm_table_get_target(t, i);
1773  
1774  		if (!ti->num_discard_bios)
1775  			return false;
1776  
1777  		/*
1778  		 * Either the target provides discard support (as implied by setting
1779  		 * 'discards_supported') or it relies on _all_ data devices having
1780  		 * discard support.
1781  		 */
1782  		if (!ti->discards_supported &&
1783  		    (!ti->type->iterate_devices ||
1784  		     ti->type->iterate_devices(ti, device_not_discard_capable, NULL)))
1785  			return false;
1786  	}
1787  
1788  	return true;
1789  }
1790  
device_not_secure_erase_capable(struct dm_target * ti,struct dm_dev * dev,sector_t start,sector_t len,void * data)1791  static int device_not_secure_erase_capable(struct dm_target *ti,
1792  					   struct dm_dev *dev, sector_t start,
1793  					   sector_t len, void *data)
1794  {
1795  	return !bdev_max_secure_erase_sectors(dev->bdev);
1796  }
1797  
dm_table_supports_secure_erase(struct dm_table * t)1798  static bool dm_table_supports_secure_erase(struct dm_table *t)
1799  {
1800  	for (unsigned int i = 0; i < t->num_targets; i++) {
1801  		struct dm_target *ti = dm_table_get_target(t, i);
1802  
1803  		if (!ti->num_secure_erase_bios)
1804  			return false;
1805  
1806  		if (!ti->type->iterate_devices ||
1807  		    ti->type->iterate_devices(ti, device_not_secure_erase_capable, NULL))
1808  			return false;
1809  	}
1810  
1811  	return true;
1812  }
1813  
dm_table_set_restrictions(struct dm_table * t,struct request_queue * q,struct queue_limits * limits)1814  int dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
1815  			      struct queue_limits *limits)
1816  {
1817  	int r;
1818  
1819  	if (!dm_table_supports_nowait(t))
1820  		limits->features &= ~BLK_FEAT_NOWAIT;
1821  
1822  	/*
1823  	 * The current polling impementation does not support request based
1824  	 * stacking.
1825  	 */
1826  	if (!__table_type_bio_based(t->type))
1827  		limits->features &= ~BLK_FEAT_POLL;
1828  
1829  	if (!dm_table_supports_discards(t)) {
1830  		limits->max_hw_discard_sectors = 0;
1831  		limits->discard_granularity = 0;
1832  		limits->discard_alignment = 0;
1833  	}
1834  
1835  	if (!dm_table_supports_write_zeroes(t))
1836  		limits->max_write_zeroes_sectors = 0;
1837  
1838  	if (!dm_table_supports_secure_erase(t))
1839  		limits->max_secure_erase_sectors = 0;
1840  
1841  	if (dm_table_supports_flush(t))
1842  		limits->features |= BLK_FEAT_WRITE_CACHE | BLK_FEAT_FUA;
1843  
1844  	if (dm_table_supports_dax(t, device_not_dax_capable)) {
1845  		limits->features |= BLK_FEAT_DAX;
1846  		if (dm_table_supports_dax(t, device_not_dax_synchronous_capable))
1847  			set_dax_synchronous(t->md->dax_dev);
1848  	} else
1849  		limits->features &= ~BLK_FEAT_DAX;
1850  
1851  	if (dm_table_any_dev_attr(t, device_dax_write_cache_enabled, NULL))
1852  		dax_write_cache(t->md->dax_dev, true);
1853  
1854  	/* For a zoned table, setup the zone related queue attributes. */
1855  	if (IS_ENABLED(CONFIG_BLK_DEV_ZONED) &&
1856  	    (limits->features & BLK_FEAT_ZONED)) {
1857  		r = dm_set_zones_restrictions(t, q, limits);
1858  		if (r)
1859  			return r;
1860  	}
1861  
1862  	r = queue_limits_set(q, limits);
1863  	if (r)
1864  		return r;
1865  
1866  	/*
1867  	 * Now that the limits are set, check the zones mapped by the table
1868  	 * and setup the resources for zone append emulation if necessary.
1869  	 */
1870  	if (IS_ENABLED(CONFIG_BLK_DEV_ZONED) &&
1871  	    (limits->features & BLK_FEAT_ZONED)) {
1872  		r = dm_revalidate_zones(t, q);
1873  		if (r)
1874  			return r;
1875  	}
1876  
1877  	dm_update_crypto_profile(q, t);
1878  	return 0;
1879  }
1880  
dm_table_get_devices(struct dm_table * t)1881  struct list_head *dm_table_get_devices(struct dm_table *t)
1882  {
1883  	return &t->devices;
1884  }
1885  
dm_table_get_mode(struct dm_table * t)1886  blk_mode_t dm_table_get_mode(struct dm_table *t)
1887  {
1888  	return t->mode;
1889  }
1890  EXPORT_SYMBOL(dm_table_get_mode);
1891  
1892  enum suspend_mode {
1893  	PRESUSPEND,
1894  	PRESUSPEND_UNDO,
1895  	POSTSUSPEND,
1896  };
1897  
suspend_targets(struct dm_table * t,enum suspend_mode mode)1898  static void suspend_targets(struct dm_table *t, enum suspend_mode mode)
1899  {
1900  	lockdep_assert_held(&t->md->suspend_lock);
1901  
1902  	for (unsigned int i = 0; i < t->num_targets; i++) {
1903  		struct dm_target *ti = dm_table_get_target(t, i);
1904  
1905  		switch (mode) {
1906  		case PRESUSPEND:
1907  			if (ti->type->presuspend)
1908  				ti->type->presuspend(ti);
1909  			break;
1910  		case PRESUSPEND_UNDO:
1911  			if (ti->type->presuspend_undo)
1912  				ti->type->presuspend_undo(ti);
1913  			break;
1914  		case POSTSUSPEND:
1915  			if (ti->type->postsuspend)
1916  				ti->type->postsuspend(ti);
1917  			break;
1918  		}
1919  	}
1920  }
1921  
dm_table_presuspend_targets(struct dm_table * t)1922  void dm_table_presuspend_targets(struct dm_table *t)
1923  {
1924  	if (!t)
1925  		return;
1926  
1927  	suspend_targets(t, PRESUSPEND);
1928  }
1929  
dm_table_presuspend_undo_targets(struct dm_table * t)1930  void dm_table_presuspend_undo_targets(struct dm_table *t)
1931  {
1932  	if (!t)
1933  		return;
1934  
1935  	suspend_targets(t, PRESUSPEND_UNDO);
1936  }
1937  
dm_table_postsuspend_targets(struct dm_table * t)1938  void dm_table_postsuspend_targets(struct dm_table *t)
1939  {
1940  	if (!t)
1941  		return;
1942  
1943  	suspend_targets(t, POSTSUSPEND);
1944  }
1945  
dm_table_resume_targets(struct dm_table * t)1946  int dm_table_resume_targets(struct dm_table *t)
1947  {
1948  	unsigned int i;
1949  	int r = 0;
1950  
1951  	lockdep_assert_held(&t->md->suspend_lock);
1952  
1953  	for (i = 0; i < t->num_targets; i++) {
1954  		struct dm_target *ti = dm_table_get_target(t, i);
1955  
1956  		if (!ti->type->preresume)
1957  			continue;
1958  
1959  		r = ti->type->preresume(ti);
1960  		if (r) {
1961  			DMERR("%s: %s: preresume failed, error = %d",
1962  			      dm_device_name(t->md), ti->type->name, r);
1963  			return r;
1964  		}
1965  	}
1966  
1967  	for (i = 0; i < t->num_targets; i++) {
1968  		struct dm_target *ti = dm_table_get_target(t, i);
1969  
1970  		if (ti->type->resume)
1971  			ti->type->resume(ti);
1972  	}
1973  
1974  	return 0;
1975  }
1976  
dm_table_get_md(struct dm_table * t)1977  struct mapped_device *dm_table_get_md(struct dm_table *t)
1978  {
1979  	return t->md;
1980  }
1981  EXPORT_SYMBOL(dm_table_get_md);
1982  
dm_table_device_name(struct dm_table * t)1983  const char *dm_table_device_name(struct dm_table *t)
1984  {
1985  	return dm_device_name(t->md);
1986  }
1987  EXPORT_SYMBOL_GPL(dm_table_device_name);
1988  
dm_table_run_md_queue_async(struct dm_table * t)1989  void dm_table_run_md_queue_async(struct dm_table *t)
1990  {
1991  	if (!dm_table_request_based(t))
1992  		return;
1993  
1994  	if (t->md->queue)
1995  		blk_mq_run_hw_queues(t->md->queue, true);
1996  }
1997  EXPORT_SYMBOL(dm_table_run_md_queue_async);
1998  
1999