Release 4.11 drivers/md/dm-table.c

/*
 * Copyright (C) 2001 Sistina Software (UK) Limited.
 * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
 *
 * This file is released under the GPL.
 */

#include "dm-core.h"

#include <linux/module.h>
#include <linux/vmalloc.h>
#include <linux/blkdev.h>
#include <linux/namei.h>
#include <linux/ctype.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/mutex.h>
#include <linux/delay.h>
#include <linux/atomic.h>
#include <linux/blk-mq.h>
#include <linux/mount.h>


#define DM_MSG_PREFIX "table"


#define MAX_DEPTH 16

#define NODE_SIZE L1_CACHE_BYTES

#define KEYS_PER_NODE (NODE_SIZE / sizeof(sector_t))

#define CHILDREN_PER_NODE (KEYS_PER_NODE + 1)


struct dm_table {
	
struct mapped_device *md;
	
unsigned type;

	/* btree table */
	
unsigned int depth;
	
unsigned int counts[MAX_DEPTH];	/* in nodes */
	
sector_t *index[MAX_DEPTH];

	
unsigned int num_targets;
	
unsigned int num_allocated;
	
sector_t *highs;
	
struct dm_target *targets;

	
struct target_type *immutable_target_type;

	
bool integrity_supported:1;
	
bool singleton:1;
	
bool all_blk_mq:1;

	/*
         * Indicates the rw permissions for the new logical
         * device.  This should be a combination of FMODE_READ
         * and FMODE_WRITE.
         */
	
fmode_t mode;

	/* a list of devices used by this table */
	
struct list_head devices;

	/* events get handed up using this callback */
	
void (*event_fn)(void *);
	
void *event_context;

	
struct dm_md_mempools *mempools;

	
struct list_head target_callbacks;
};

/*
 * Similar to ceiling(log_size(n))
 */


static unsigned int int_log(unsigned int n, unsigned int base)
{
	int result = 0;

	while (n > 1) {
		n = dm_div_up(n, base);
		result++;
	}

	return result;
}

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40
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2
4.65%
1
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Joe Thornber
1
2.33%
1
33.33%
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43
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3
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/*
 * Calculate the index of the child node of the n'th node k'th key.
 */


static inline unsigned int get_child(unsigned int n, unsigned int k)
{
	return (n * CHILDREN_PER_NODE) + k;
}

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3
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25
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/*
 * Return the n'th node of level l from table t.
 */


static inline sector_t *get_node(struct dm_table *t,
				 unsigned int l, unsigned int n)
{
	return t->index[l] + (n * KEYS_PER_NODE);
}

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/*
 * Return the highest key that you could lookup from the n'th
 * node on level l of the btree.
 */


static sector_t high(struct dm_table *t, unsigned int l, unsigned int n)
{
	for (; l < t->depth - 1; l++)
		n = get_child(n, CHILDREN_PER_NODE - 1);

	if (n >= t->counts[l])
		return (sector_t) - 1;

	return get_node(t, l, n)[KEYS_PER_NODE - 1];
}

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/*
 * Fills in a level of the btree based on the highs of the level
 * below it.
 */


static int setup_btree_index(unsigned int l, struct dm_table *t)
{
	unsigned int n, k;
	sector_t *node;

	for (n = 0U; n < t->counts[l]; n++) {
		node = get_node(t, l, n);

		for (k = 0U; k < KEYS_PER_NODE; k++)
			node[k] = high(t, l + 1, get_child(n, k));
	}

	return 0;
}

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void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size)
{
	unsigned long size;
	void *addr;

	/*
         * Check that we're not going to overflow.
         */
	if (nmemb > (ULONG_MAX / elem_size))
		return NULL;

	size = nmemb * elem_size;
	addr = vzalloc(size);

	return addr;
}
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EXPORT_SYMBOL(dm_vcalloc);

/*
 * highs, and targets are managed as dynamic arrays during a
 * table load.
 */


static int alloc_targets(struct dm_table *t, unsigned int num)
{
	sector_t *n_highs;
	struct dm_target *n_targets;

	/*
         * Allocate both the target array and offset array at once.
         * Append an empty entry to catch sectors beyond the end of
         * the device.
         */
	n_highs = (sector_t *) dm_vcalloc(num + 1, sizeof(struct dm_target) +
					  sizeof(sector_t));
	if (!n_highs)
		return -ENOMEM;

	n_targets = (struct dm_target *) (n_highs + num);

	memset(n_highs, -1, sizeof(*n_highs) * num);
	vfree(t->highs);

	t->num_allocated = num;
	t->highs = n_highs;
	t->targets = n_targets;

	return 0;
}

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Jun'ichi Nomura
3
2.61%
1
20.00%
Andrew Morton
2
1.74%
1
20.00%
Joe Thornber
1
0.87%
1
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115
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5
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int dm_table_create(struct dm_table **result, fmode_t mode,
		    unsigned num_targets, struct mapped_device *md)
{
	struct dm_table *t = kzalloc(sizeof(*t), GFP_KERNEL);

	if (!t)
		return -ENOMEM;

	INIT_LIST_HEAD(&t->devices);
	INIT_LIST_HEAD(&t->target_callbacks);

	if (!num_targets)
		num_targets = KEYS_PER_NODE;

	num_targets = dm_round_up(num_targets, KEYS_PER_NODE);

	if (!num_targets) {
		kfree(t);
		return -ENOMEM;
	}

	if (alloc_targets(t, num_targets)) {
		kfree(t);
		return -ENOMEM;
	}

	t->type = DM_TYPE_NONE;
	t->mode = mode;
	t->md = md;
	*result = t;
	return 0;
}

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53.85%
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23
16.08%
2
22.22%
Mikulas Patocka
16
11.19%
1
11.11%
Mike Anderson
11
7.69%
1
11.11%
Neil Brown
8
5.59%
1
11.11%
Mike Snitzer
6
4.20%
1
11.11%
Al Viro
1
0.70%
1
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Dmitriy Monakhov
1
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1
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143
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9
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static void free_devices(struct list_head *devices, struct mapped_device *md)
{
	struct list_head *tmp, *next;

	list_for_each_safe(tmp, next, devices) {
		struct dm_dev_internal *dd =
		    list_entry(tmp, struct dm_dev_internal, list);
		DMWARN("%s: dm_table_destroy: dm_put_device call missing for %s",
		       dm_device_name(md), dd->dm_dev->name);
		dm_put_table_device(md, dd->dm_dev);
		kfree(dd);
	}
}

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Alan Cox
39
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Benjamin Marzinski
21
26.58%
1
20.00%
Jonathan E Brassow
9
11.39%
1
20.00%
Paul Jimenez
8
10.13%
1
20.00%
Mikulas Patocka
2
2.53%
1
20.00%
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79
100.00%
5
100.00%



void dm_table_destroy(struct dm_table *t)
{
	unsigned int i;

	if (!t)
		return;

	/* free the indexes */
	if (t->depth >= 2)
		vfree(t->index[t->depth - 2]);

	/* free the targets */
	for (i = 0; i < t->num_targets; i++) {
		struct dm_target *tgt = t->targets + i;

		if (tgt->type->dtr)
			tgt->type->dtr(tgt);

		dm_put_target_type(tgt->type);
	}

	vfree(t->highs);

	/* free the device list */
	free_devices(&t->devices, t->md);

	dm_free_md_mempools(t->mempools);

	kfree(t);
}

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9
7.03%
2
25.00%
Kiyoshi Ueda
7
5.47%
1
12.50%
Alasdair G. Kergon
6
4.69%
1
12.50%
Benjamin Marzinski
4
3.12%
1
12.50%
Will Drewry
1
0.78%
1
12.50%
Mikulas Patocka
1
0.78%
1
12.50%
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128
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8
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/*
 * See if we've already got a device in the list.
 */


static struct dm_dev_internal *find_device(struct list_head *l, dev_t dev)
{
	struct dm_dev_internal *dd;

	list_for_each_entry (dd, l, list)
		if (dd->dm_dev->bdev->bd_dev == dev)
			return dd;

	return NULL;
}

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5
10.64%
1
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Mikulas Patocka
3
6.38%
1
25.00%
Benjamin Marzinski
1
2.13%
1
25.00%
Total
47
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4
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/*
 * If possible, this checks an area of a destination device is invalid.
 */


static int device_area_is_invalid(struct dm_target *ti, struct dm_dev *dev,
				  sector_t start, sector_t len, void *data)
{
	struct request_queue *q;
	struct queue_limits *limits = data;
	struct block_device *bdev = dev->bdev;
	sector_t dev_size =
		i_size_read(bdev->bd_inode) >> SECTOR_SHIFT;
	unsigned short logical_block_size_sectors =
		limits->logical_block_size >> SECTOR_SHIFT;
	char b[BDEVNAME_SIZE];

	/*
         * Some devices exist without request functions,
         * such as loop devices not yet bound to backing files.
         * Forbid the use of such devices.
         */
	q = bdev_get_queue(bdev);
	if (!q || !q->make_request_fn) {
		DMWARN("%s: %s is not yet initialised: "
		       "start=%llu, len=%llu, dev_size=%llu",
		       dm_device_name(ti->table->md), bdevname(bdev, b),
		       (unsigned long long)start,
		       (unsigned long long)len,
		       (unsigned long long)dev_size);
		return 1;
	}

	if (!dev_size)
		return 0;

	if ((start >= dev_size) || (start + len > dev_size)) {
		DMWARN("%s: %s too small for target: "
		       "start=%llu, len=%llu, dev_size=%llu",
		       dm_device_name(ti->table->md), bdevname(bdev, b),
		       (unsigned long long)start,
		       (unsigned long long)len,
		       (unsigned long long)dev_size);
		return 1;
	}

	if (logical_block_size_sectors <= 1)
		return 0;

	if (start & (logical_block_size_sectors - 1)) {
		DMWARN("%s: start=%llu not aligned to h/w "
		       "logical block size %u of %s",
		       dm_device_name(ti->table->md),
		       (unsigned long long)start,
		       limits->logical_block_size, bdevname(bdev, b));
		return 1;
	}

	if (len & (logical_block_size_sectors - 1)) {
		DMWARN("%s: len=%llu not aligned to h/w "
		       "logical block size %u of %s",
		       dm_device_name(ti->table->md),
		       (unsigned long long)len,
		       limits->logical_block_size, bdevname(bdev, b));
		return 1;
	}

	return 0;
}

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Mike Snitzer
199
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4
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Milan Broz
71
22.12%
1
10.00%
Alan Cox
30
9.35%
1
10.00%
Mikulas Patocka
10
3.12%
2
20.00%
Mike Anderson
9
2.80%
1
10.00%
Joe Thornber
2
0.62%
1
10.00%
Total
321
100.00%
10
100.00%

/*
 * This upgrades the mode on an already open dm_dev, being
 * careful to leave things as they were if we fail to reopen the
 * device and not to touch the existing bdev field in case
 * it is accessed concurrently inside dm_table_any_congested().
 */


static int upgrade_mode(struct dm_dev_internal *dd, fmode_t new_mode,
			struct mapped_device *md)
{
	int r;
	struct dm_dev *old_dev, *new_dev;

	old_dev = dd->dm_dev;

	r = dm_get_table_device(md, dd->dm_dev->bdev->bd_dev,
				dd->dm_dev->mode | new_mode, &new_dev);
	if (r)
		return r;

	dd->dm_dev = new_dev;
	dm_put_table_device(md, old_dev);

	return 0;
}

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25
29.41%
1
14.29%
Alasdair G. Kergon
15
17.65%
1
14.29%
Jun'ichi Nomura
7
8.24%
1
14.29%
Mikulas Patocka
2
2.35%
1
14.29%
Kevin Corry
1
1.18%
1
14.29%
Al Viro
1
1.18%
1
14.29%
Total
85
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7
100.00%

/*
 * Convert the path to a device
 */


dev_t dm_get_dev_t(const char *path)
{
	dev_t uninitialized_var(dev);
	struct block_device *bdev;

	bdev = lookup_bdev(path);
	if (IS_ERR(bdev))
		dev = name_to_dev_t(path);
	else {
		dev = bdev->bd_dev;
		bdput(bdev);
	}

	return dev;
}
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EXPORT_SYMBOL_GPL(dm_get_dev_t);

/*
 * Add a device to the list, or just increment the usage count if
 * it's already present.
 */


int dm_get_device(struct dm_target *ti, const char *path, fmode_t mode,
		  struct dm_dev **result)
{
	int r;
	dev_t dev;
	struct dm_dev_internal *dd;
	struct dm_table *t = ti->table;

	BUG_ON(!t);

	dev = dm_get_dev_t(path);
	if (!dev)
		return -ENODEV;

	dd = find_device(&t->devices, dev);
	if (!dd) {
		dd = kmalloc(sizeof(*dd), GFP_KERNEL);
		if (!dd)
			return -ENOMEM;

		if ((r = dm_get_table_device(t->md, dev, mode, &dd->dm_dev))) {
			kfree(dd);
			return r;
		}

		atomic_set(&dd->count, 0);
		list_add(&dd->list, &t->devices);

	} else if (dd->dm_dev->mode != (mode | dd->dm_dev->mode)) {
		r = upgrade_mode(dd, mode, t->md);
		if (r)
			return r;
	}
	atomic_inc(&dd->count);

	*result = dd->dm_dev;
	return 0;
}
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11
4.98%
1
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Mike Snitzer
10
4.52%
1
10.00%
Al Viro
8
3.62%
2
20.00%
Jun'ichi Nomura
6
2.71%
1
10.00%
Mikulas Patocka
5
2.26%
1
10.00%
Eric Sesterhenn / Snakebyte
3
1.36%
1
10.00%
Dan Ehrenberg
3
1.36%
1
10.00%
DingXiang
1
0.45%
1
10.00%
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221
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10
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EXPORT_SYMBOL(dm_get_device);



static int dm_set_device_limits(struct dm_target *ti, struct dm_dev *dev,
				sector_t start, sector_t len, void *data)
{
	struct queue_limits *limits = data;
	struct block_device *bdev = dev->bdev;
	struct request_queue *q = bdev_get_queue(bdev);
	char b[BDEVNAME_SIZE];

	if (unlikely(!q)) {
		DMWARN("%s: Cannot set limits for nonexistent device %s",
		       dm_device_name(ti->table->md), bdevname(bdev, b));
		return 0;
	}

	if (bdev_stack_limits(limits, bdev, start) < 0)
		DMWARN("%s: adding target device %s caused an alignment inconsistency: "
		       "physical_block_size=%u, logical_block_size=%u, "
		       "alignment_offset=%u, start=%llu",
		       dm_device_name(ti->table->md), bdevname(bdev, b),
		       q->limits.physical_block_size,
		       q->limits.logical_block_size,
		       q->limits.alignment_offset,
		       (unsigned long long) start << SECTOR_SHIFT);

	return 0;
}

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Alasdair G. Kergon
37
23.42%
1
9.09%
Alan Cox
24
15.19%
1
9.09%
Martin K. Petersen
6
3.80%
2
18.18%
Jens Axboe
2
1.27%
1
9.09%
Bryn M. Reeves
1
0.63%
1
9.09%
Total
158
100.00%
11
100.00%

/*
 * Decrement a device's use count and remove it if necessary.
 */


void dm_put_device(struct dm_target *ti, struct dm_dev *d)
{
	int found = 0;
	struct list_head *devices = &ti->table->devices;
	struct dm_dev_internal *dd;

	list_for_each_entry(dd, devices, list) {
		if (dd->dm_dev == d) {
			found = 1;
			break;
		}
	}
	if (!found) {
		DMWARN("%s: device %s not in table devices list",
		       dm_device_name(ti->table->md), d->name);
		return;
	}
	if (atomic_dec_and_test(&dd->count)) {
		dm_put_table_device(ti->table->md, d);
		list_del(&dd->list);
		kfree(dd);
	}
}
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42
33.87%
1
25.00%
Mikulas Patocka
10
8.06%
1
25.00%
Jun'ichi Nomura
5
4.03%
1
25.00%
Total
124
100.00%
4
100.00%


EXPORT_SYMBOL(dm_put_device);

/*
 * Checks to see if the target joins onto the end of the table.
 */


static int adjoin(struct dm_table *table, struct dm_target *ti)
{
	struct dm_target *prev;

	if (!table->num_targets)
		return !ti->begin;

	prev = &table->targets[table->num_targets - 1];
	return (ti->begin == (prev->begin + prev->len));
}

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/*
 * Used to dynamically allocate the arg array.
 *
 * We do first allocation with GFP_NOIO because dm-mpath and dm-thin must
 * process messages even if some device is suspended. These messages have a
 * small fixed number of arguments.
 *
 * On the other hand, dm-switch needs to process bulk data using messages and
 * excessive use of GFP_NOIO could cause trouble.
 */


static char **realloc_argv(unsigned *array_size, char **old_argv)
{
	char **argv;
	unsigned new_size;
	gfp_t gfp;

	if (*array_size) {
		new_size = *array_size * 2;
		gfp = GFP_KERNEL;
	} else {
		new_size = 8;
		gfp = GFP_NOIO;
	}
	argv = kmalloc(new_size * sizeof(*argv), gfp);
	if (argv) {
		memcpy(argv, old_argv, *array_size * sizeof(*argv));
		*array_size = new_size;
	}

	kfree(old_argv);
	return argv;
}

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107
100.00%
2
100.00%

/*
 * Destructively splits up the argument list to pass to ctr.
 */


int dm_split_args(int *argc, char ***argvp, char *input)
{
	char *start, *end = input, *out, **argv = NULL;
	unsigned array_size = 0;

	*argc = 0;

	if (!input) {
		*argvp = NULL;
		return 0;
	}

	argv = realloc_argv(&array_size, argv);
	if (!argv)
		return -ENOMEM;

	while (1) {
		/* Skip whitespace */
		start = skip_spaces(end);

		if (!*start)
			break;	/* success, we hit the end */

		/* 'out' is used to remove any back-quotes */
		end = out = start;
		while (*end) {
			/* Everything apart from '\0' can be quoted */
			if (*end == '\\' && *(end + 1)) {
				*out++ = *(end + 1);
				end += 2;
				continue;
			}

			if (isspace(*end))
				break;	/* end of token */

			*out++ = *end++;
		}

		/* have we already filled the array ? */
		if ((*argc + 1) > array_size) {
			argv = realloc_argv(&array_size, argv);
			if (!argv)
				return -ENOMEM;
		}

		/* we know this is whitespace */
		if (*end)
			end++;

		/* terminate the string and put it in the array */
		*out = '\0';
		argv[*argc] = start;
		(*argc)++;
	}

	*argvp = argv;
	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Alan Cox
163
68.49%
1
20.00%
Kevin Corry
56
23.53%
1
20.00%
David Teigland
15
6.30%
1
20.00%
André Goddard Rosa
3
1.26%
1
20.00%
Alasdair G. Kergon
1
0.42%
1
20.00%
Total
238
100.00%
5
100.00%

/*
 * Impose necessary and sufficient conditions on a devices's table such
 * that any incoming bio which respects its logical_block_size can be
 * processed successfully.  If it falls across the boundary between
 * two or more targets, the size of each piece it gets split into must
 * be compatible with the logical_block_size of the target processing it.
 */


static int validate_hardware_logical_block_alignment(struct dm_table *table,
						 struct queue_limits *limits)
{
	/*
         * This function uses arithmetic modulo the logical_block_size
         * (in units of 512-byte sectors).
         */
	unsigned short device_logical_block_size_sects =
		limits->logical_block_size >> SECTOR_SHIFT;

	/*
         * Offset of the start of the next table entry, mod logical_block_size.
         */
	unsigned short next_target_start = 0;

	/*
         * Given an aligned bio that extends beyond the end of a
         * target, how many sectors must the next target handle?
         */
	unsigned short remaining = 0;

	struct dm_target *uninitialized_var(ti);
	struct queue_limits ti_limits;
	unsigned i = 0;

	/*
         * Check each entry in the table in turn.
         */
	while (i < dm_table_get_num_targets(table)) {
		ti = dm_table_get_target(table, i++);

		blk_set_stacking_limits(&ti_limits);

		/* combine all target devices' limits */
		if (ti->type->iterate_devices)
			ti->type->iterate_devices(ti, dm_set_device_limits,
						  &ti_limits);

		/*
                 * If the remaining sectors fall entirely within this
                 * table entry are they compatible with its logical_block_size?
                 */
		if (remaining < ti->len &&
		    remaining & ((ti_limits.logical_block_size >>
				  SECTOR_SHIFT) - 1))
			break;	/* Error */

		next_target_start =
		    (unsigned short) ((next_target_start + ti->len) &
				      (device_logical_block_size_sects - 1));
		remaining = next_target_start ?
		    device_logical_block_size_sects - next_target_start : 0;
	}

	if (remaining) {
		DMWARN("%s: table line %u (start sect %llu len %llu) "
		       "not aligned to h/w logical block size %u",
		       dm_device_name(table->md), i,
		       (unsigned long long) ti->begin,
		       (unsigned long long) ti->len,
		       limits->logical_block_size);
		return -EINVAL;
	}

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Mike Snitzer
199
92.13%
4
50.00%
Andrew Morton
13
6.02%
2
25.00%
Neil Brown
3
1.39%
1
12.50%
Martin K. Petersen
1
0.46%
1
12.50%
Total
216
100.00%
8
100.00%



int dm_table_add_target(struct dm_table *t, const char *type,
			sector_t start, sector_t len, char *params)
{
	int r = -EINVAL, argc;
	char **argv;
	struct dm_target *tgt;

	if (t->singleton) {
		DMERR("%s: target type %s must appear alone in table",
		      dm_device_name(t->md), t->targets->type->name);
		return -EINVAL;
	}

	BUG_ON(t->num_targets >= t->num_allocated);

	tgt = t->targets + t->num_targets;
	memset(tgt, 0, sizeof(*tgt));

	if (!len) {
		DMERR("%s: zero-length target", dm_device_name(t->md));
		return -EINVAL;
	}

	tgt->type = dm_get_target_type(type);
	if (!tgt->type) {
		DMERR("%s: %s: unknown target type", dm_device_name(t->md), type);
		return -EINVAL;
	}

	if (dm_target_needs_singleton(tgt->type)) {
		if (t->num_targets) {
			tgt->error = "singleton target type must appear alone in table";
			goto bad;
		}
		t->singleton = true;
	}

	if (dm_target_always_writeable(tgt->type) && !(t->mode & FMODE_WRITE)) {
		tgt->error = "target type may not be included in a read-only table";
		goto bad;
	}

	if (t->immutable_target_type) {
		if (t->immutable_target_type != tgt->type) {
			tgt->error = "immutable target type cannot be mixed with other target types";
			goto bad;
		}
	} else if (dm_target_is_immutable(tgt->type)) {
		if (t->num_targets) {
			tgt->error = "immutable target type cannot be mixed with other target types";
			goto bad;
		}
		t->immutable_target_type = tgt->type;
	}

	tgt->table = t;
	tgt->begin = start;
	tgt->len = len;
	tgt->error = "Unknown error";

	/*
         * Does this target adjoin the previous one ?
         */
	if (!adjoin(t, tgt)) {
		tgt->error = "Gap in table";
		goto bad;
	}

	r = dm_split_args(&argc, &argv, params);
	if (r) {
		tgt->error = "couldn't split parameters (insufficient memory)";
		goto bad;
	}

	r = tgt->type->ctr(tgt, argc, argv);
	kfree(argv);
	if (r)
		goto bad;

	t->highs[t->num_targets++] = tgt->begin + tgt->len - 1;

	if (!tgt->num_discard_bios && tgt->discards_supported)
		DMWARN("%s: %s: ignoring discards_supported because num_discard_bios is zero.",
		       dm_device_name(t->md), type);

	return 0;

 bad:
	DMERR("%s: %s: %s", dm_device_name(t->md), type, tgt->error);
	dm_put_target_type(tgt->type);
	return r;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Alan Cox
179
37.61%
1
5.56%
Alasdair G. Kergon
158
33.19%
6
33.33%
Joe Thornber
44
9.24%
3
16.67%
Andrew Morton
28
5.88%
2
11.11%
tang.junhui
27
5.67%
1
5.56%
Mike Snitzer
24
5.04%
3
16.67%
Mikulas Patocka
8
1.68%
1
5.56%
Kevin Corry
8
1.68%
1
5.56%
Total
476
100.00%
18
100.00%

/*
 * Target argument parsing helpers.
 */


static int validate_next_arg(struct dm_arg *arg, struct dm_arg_set *arg_set,
			     unsigned *value, char **error, unsigned grouped)
{
	const char *arg_str = dm_shift_arg(arg_set);
	char dummy;

	if (!arg_str ||
	    (sscanf(arg_str, "%u%c", value, &dummy) != 1) ||
	    (*value < arg->min) ||
	    (*value > arg->max) ||
	    (grouped && arg_set->argc < *value)) {
		*error = arg->error;
		return -EINVAL;
	}

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Mike Snitzer
100
93.46%
1
50.00%
Mikulas Patocka
7
6.54%
1
50.00%
Total
107
100.00%
2
100.00%



int dm_read_arg(struct dm_arg *arg, struct dm_arg_set *arg_set,
		unsigned *value, char **error)
{
	return validate_next_arg(arg, arg_set, value, error, 0);
}
Contributors
Person
Tokens
Prop
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CommitProp
Mike Snitzer
38
100.00%
1
100.00%
Total
38
100.00%
1
100.00%


EXPORT_SYMBOL(dm_read_arg);



int dm_read_arg_group(struct dm_arg *arg, struct dm_arg_set *arg_set,
		      unsigned *value, char **error)
{
	return validate_next_arg(arg, arg_set, value, error, 1);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Mike Snitzer
38
100.00%
1
100.00%
Total
38
100.00%
1
100.00%


EXPORT_SYMBOL(dm_read_arg_group);



const char *dm_shift_arg(struct dm_arg_set *as)
{
	char *r;

	if (as->argc) {
		as->argc--;
		r = *as->argv;
		as->argv++;
		return r;
	}

	return NULL;
}
Contributors
Person
Tokens
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CommitProp
Mike Snitzer
47
100.00%
1
100.00%
Total
47
100.00%
1
100.00%


EXPORT_SYMBOL(dm_shift_arg);



void dm_consume_args(struct dm_arg_set *as, unsigned num_args)
{
	BUG_ON(as->argc < num_args);
	as->argc -= num_args;
	as->argv += num_args;
}
Contributors
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Tokens
Prop
Commits
CommitProp
Mike Snitzer
34
100.00%
1
100.00%
Total
34
100.00%
1
100.00%


EXPORT_SYMBOL(dm_consume_args);



static bool __table_type_bio_based(unsigned table_type)
{
	return (table_type == DM_TYPE_BIO_BASED ||
		table_type == DM_TYPE_DAX_BIO_BASED);
}

Contributors
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Toshi Kani
20
100.00%
1
100.00%
Total
20
100.00%
1
100.00%



static bool __table_type_request_based(unsigned table_type)
{
	return (table_type == DM_TYPE_REQUEST_BASED ||
		table_type == DM_TYPE_MQ_REQUEST_BASED);
}

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Jun'ichi Nomura
20
100.00%
1
100.00%
Total
20
100.00%
1
100.00%



void dm_table_set_type(struct dm_table *t, unsigned type)
{
	t->type = type;
}
Contributors
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Mike Snitzer
19
100.00%
1
100.00%
Total
19
100.00%
1
100.00%


EXPORT_SYMBOL_GPL(dm_table_set_type);



static int device_supports_dax(struct dm_target *ti, struct dm_dev *dev,
			       sector_t start, sector_t len, void *data)
{
	struct request_queue *q = bdev_get_queue(dev->bdev);

	return q && blk_queue_dax(q);
}

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Toshi Kani
46
100.00%
1
100.00%
Total
46
100.00%
1
100.00%



static bool dm_table_supports_dax(struct dm_table *t)
{
	struct dm_target *ti;
	unsigned i = 0;

	/* Ensure that all targets support DAX. */
	while (i < dm_table_get_num_targets(t)) {
		ti = dm_table_get_target(t, i++);

		if (!ti->type->direct_access)
			return false;

		if (!ti->type->iterate_devices ||
		    !ti->type->iterate_devices(ti, device_supports_dax, NULL))
			return false;
	}

	return true;
}

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Toshi Kani
84
100.00%
1
100.00%
Total
84
100.00%
1
100.00%



static int dm_table_determine_type(struct dm_table *t)
{
	unsigned i;
	unsigned bio_based = 0, request_based = 0, hybrid = 0;
	unsigned sq_count = 0, mq_count = 0;
	struct dm_target *tgt;
	struct dm_dev_internal *dd;
	struct list_head *devices = dm_table_get_devices(t);
	unsigned live_md_type = dm_get_md_type(t->md);

	if (t->type != DM_TYPE_NONE) {
		/* target already set the table's type */
		if (t->type == DM_TYPE_BIO_BASED)
			return 0;
		BUG_ON(t->type == DM_TYPE_DAX_BIO_BASED);
		goto verify_rq_based;
	}

	for (i = 0; i < t->num_targets; i++) {
		tgt = t->targets + i;
		if (dm_target_hybrid(tgt))
			hybrid = 1;
		else if (dm_target_request_based(tgt))
			request_based = 1;
		else
			bio_based = 1;

		if (bio_based && request_based) {
			DMWARN("Inconsistent table: different target types"
			       " can't be mixed up");
			return -EINVAL;
		}
	}

	if (hybrid && !bio_based && !request_based) {
		/*
                 * The targets can work either way.
                 * Determine the type from the live device.
                 * Default to bio-based if device is new.
                 */
		if (__table_type_request_based(live_md_type))
			request_based = 1;
		else
			bio_based = 1;
	}

	if (bio_based) {
		/* We must use this table as bio-based */
		t->type = DM_TYPE_BIO_BASED;
		if (dm_table_supports_dax(t) ||
		    (list_empty(devices) && live_md_type == DM_TYPE_DAX_BIO_BASED))
			t->type = DM_TYPE_DAX_BIO_BASED;
		return 0;
	}

	BUG_ON(!request_based); /* No targets in this table */

	/*
         * The only way to establish DM_TYPE_MQ_REQUEST_BASED is by
         * having a compatible target use dm_table_set_type.
         */
	t->type = DM_TYPE_REQUEST_BASED;

verify_rq_based:
	/*
         * Request-based dm supports only tables that have a single target now.
         * To support multiple targets, request splitting support is needed,
         * and that needs lots of changes in the block-layer.
         * (e.g. request completion process for partial completion.)
         */
	if (t->num_targets > 1) {
		DMWARN("Request-based dm doesn't support multiple targets yet");
		return -EINVAL;
	}

	if (list_empty(devices)) {
		int srcu_idx;
		struct dm_table *live_table = dm_get_live_table(t->md, &srcu_idx);

		/* inherit live table's type and all_blk_mq */
		if (live_table) {
			t->type = live_table->type;
			t->all_blk_mq = live_table->all_blk_mq;
		}
		dm_put_live_table(t->md, srcu_idx);
		return 0;
	}

	/* Non-request-stackable devices can't be used for request-based dm */
	list_for_each_entry(dd, devices, list) {
		struct request_queue *q = bdev_get_queue(dd->dm_dev->bdev);

		if (!blk_queue_stackable(q)) {
			DMERR("table load rejected: including"
			      " non-request-stackable devices");
			return -EINVAL;
		}

		if (q->mq_ops)
			mq_count++;
		else
			sq_count++;
	}
	if (sq_count && mq_count) {
		DMERR("table load rejected: not all devices are blk-mq request-stackable");
		return -EINVAL;
	}
	t->all_blk_mq = mq_count > 0;

	if (t->type == DM_TYPE_MQ_REQUEST_BASED && !t->all_blk_mq) {
		DMERR("table load rejected: all devices are not blk-mq request-stackable");
		return -EINVAL;
	}

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Mike Snitzer
231
51.56%
6
50.00%
Kiyoshi Ueda
147
32.81%
1
8.33%
Bart Van Assche
44
9.82%
2
16.67%
Toshi Kani
22
4.91%
1
8.33%
Jun'ichi Nomura
3
0.67%
1
8.33%
Will Drewry
1
0.22%
1
8.33%
Total
448
100.00%
12
100.00%



unsigned dm_table_get_type(struct dm_table *t)
{
	return t->type;
}

Contributors
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Tokens
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CommitProp
Kiyoshi Ueda
15
100.00%
1
100.00%
Total
15
100.00%
1
100.00%



struct target_type *dm_table_get_immutable_target_type(struct dm_table *t)
{
	return t->immutable_target_type;
}

Contributors
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Alasdair G. Kergon
17
100.00%
1
100.00%
Total
17
100.00%
1
100.00%



struct dm_target *dm_table_get_immutable_target(struct dm_table *t)
{
	/* Immutable target is implicitly a singleton */
	if (t->num_targets > 1 ||
	    !dm_target_is_immutable(t->targets[0].type))
		return NULL;

	return t->targets;
}

Contributors
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Mike Snitzer
42
100.00%
1
100.00%
Total
42
100.00%
1
100.00%



struct dm_target *dm_table_get_wildcard_target(struct dm_table *t)
{
	struct dm_target *uninitialized_var(ti);
	unsigned i = 0;

	while (i < dm_table_get_num_targets(t)) {
		ti = dm_table_get_target(t, i++);
		if (dm_target_is_wildcard(ti->type))
			return ti;
	}

	return NULL;
}

Contributors
Person
Tokens
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Commits
CommitProp
Mike Snitzer
61
100.00%
1
100.00%
Total
61
100.00%
1
100.00%



bool dm_table_bio_based(struct dm_table *t)
{
	return __table_type_bio_based(dm_table_get_type(t));
}

Contributors
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Toshi Kani
19
100.00%
1
100.00%
Total
19
100.00%
1
100.00%



bool dm_table_request_based(struct dm_table *t)
{
	return __table_type_request_based(dm_table_get_type(t));
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Kiyoshi Ueda
13
68.42%
1
33.33%
Jun'ichi Nomura
4
21.05%
1
33.33%
Mike Snitzer
2
10.53%
1
33.33%
Total
19
100.00%
3
100.00%



bool dm_table_all_blk_mq_devices(struct dm_table *t)
{
	return t->all_blk_mq;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Mike Snitzer
13
86.67%
2
66.67%
Kiyoshi Ueda
2
13.33%
1
33.33%
Total
15
100.00%
3
100.00%



static int dm_table_alloc_md_mempools(struct dm_table *t, struct mapped_device *md)
{
	unsigned type = dm_table_get_type(t);
	unsigned per_io_data_size = 0;
	struct dm_target *tgt;
	unsigned i;

	if (unlikely(type == DM_TYPE_NONE)) {
		DMWARN("no table type is set, can't allocate mempools");
		return -EINVAL;
	}

	if (__table_type_bio_based(type))
		for (i = 0; i < t->num_targets; i++) {
			tgt = t->targets + i;
			per_io_data_size = max(per_io_data_size, tgt->per_io_data_size);
		}

	t->mempools = dm_alloc_md_mempools(md, type, t->integrity_supported, per_io_data_size);
	if (!t->mempools)
		return -ENOMEM;

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Mike Snitzer
45
34.35%
4
44.44%
Mikulas Patocka
40
30.53%
2
22.22%
Kiyoshi Ueda
40
30.53%
1
11.11%
Toshi Kani
3
2.29%
1
11.11%
Martin K. Petersen
3
2.29%
1
11.11%
Total
131
100.00%
9
100.00%



void dm_table_free_md_mempools(struct dm_table *t)
{
	dm_free_md_mempools(t->mempools);
	t->mempools = NULL;
}

Contributors
Person
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CommitProp
Kiyoshi Ueda
23
100.00%
1
100.00%
Total
23
100.00%
1
100.00%



struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t)
{
	return t->mempools;
}

Contributors
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Kiyoshi Ueda
17
100.00%
1
100.00%
Total
17
100.00%
1
100.00%



static int setup_indexes(struct dm_table *t)
{
	int i;
	unsigned int total = 0;
	sector_t *indexes;

	/* allocate the space for *all* the indexes */
	for (i = t->depth - 2; i >= 0; i--) {
		t->counts[i] = dm_div_up(t->counts[i + 1], CHILDREN_PER_NODE);
		total += t->counts[i];
	}

	indexes = (sector_t *) dm_vcalloc(total, (unsigned long) NODE_SIZE);
	if (!indexes)
		return -ENOMEM;

	/* set up internal nodes, bottom-up */
	for (i = t->depth - 2; i >= 0; i--) {
		t->index[i] = indexes;
		indexes += (KEYS_PER_NODE * t->counts[i]);
		setup_btree_index(i, t);
	}

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Alan Cox
148
97.37%
2
50.00%
Joe Thornber
4
2.63%
2
50.00%
Total
152
100.00%
4
100.00%

/*
 * Builds the btree to index the map.
 */


static int dm_table_build_index(struct dm_table *t)
{
	int r = 0;
	unsigned int leaf_nodes;

	/* how many indexes will the btree have ? */
	leaf_nodes = dm_div_up(t->num_targets, KEYS_PER_NODE);
	t->depth = 1 + int_log(leaf_nodes, CHILDREN_PER_NODE);

	/* leaf layer has already been set up */
	t->counts[t->depth - 1] = leaf_nodes;
	t->index[t->depth - 1] = t->highs;

	if (t->depth >= 2)
		r = setup_indexes(t);

	return r;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Alan Cox
85
92.39%
1
25.00%
Joe Thornber
5
5.43%
2
50.00%
Will Drewry
2
2.17%
1
25.00%
Total
92
100.00%
4
100.00%



static bool integrity_profile_exists(struct gendisk *disk)
{
	return !!blk_get_integrity(disk);
}

Contributors
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Martin K. Petersen
19
100.00%
1
100.00%
Total
19
100.00%
1
100.00%

/*
 * Get a disk whose integrity profile reflects the table's profile.
 * Returns NULL if integrity support was inconsistent or unavailable.
 */


static struct gendisk * dm_table_get_integrity_disk(struct dm_table *t)
{
	struct list_head *devices = dm_table_get_devices(t);
	struct dm_dev_internal *dd = NULL;
	struct gendisk *prev_disk = NULL, *template_disk = NULL;

	list_for_each_entry(dd, devices, list) {
		template_disk = dd->dm_dev->bdev->bd_disk;
		if (!integrity_profile_exists(template_disk))
			goto no_integrity;
		else if (prev_disk &&
			 blk_integrity_compare(prev_disk, template_disk) < 0)
			goto no_integrity;
		prev_disk = template_disk;
	}

	return template_disk;

no_integrity:
	if (prev_disk)
		DMWARN("%s: integrity not set: %s and %s profile mismatch",
		       dm_device_name(t->md),
		       prev_disk->disk_name,
		       template_disk->disk_name);
	return NULL;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Mike Snitzer
89
70.63%
1
25.00%
Will Drewry
35
27.78%
1
25.00%
Benjamin Marzinski
1
0.79%
1
25.00%
Martin K. Petersen
1
0.79%
1
25.00%
Total
126
100.00%
4
100.00%

/*
 * Register the mapped device for blk_integrity support if the
 * underlying devices have an integrity profile.  But all devices may
 * not have matching profiles (checking all devices isn't reliable
 * during table load because this table may use other DM device(s) which
 * must be resumed before they will have an initialized integity
 * profile).  Consequently, stacked DM devices force a 2 stage integrity
 * profile validation: First pass during table load, final pass during
 * resume.
 */


static int dm_table_register_integrity(struct dm_table *t)
{
	struct mapped_device *md = t->md;
	struct gendisk *template_disk = NULL;

	template_disk = dm_table_get_integrity_disk(t);
	if (!template_disk)
		return 0;

	if (!integrity_profile_exists(dm_disk(md))) {
		t->integrity_supported = true;
		/*
                 * Register integrity profile during table load; we can do
                 * this because the final profile must match during resume.
                 */
		blk_integrity_register(dm_disk(md),
				       blk_get_integrity(template_disk));
		return 0;
	}

	/*
         * If DM device already has an initialized integrity
         * profile the new profile should not conflict.
         */
	if (blk_integrity_compare(dm_disk(md), template_disk) < 0) {
		DMWARN("%s: conflict with existing integrity profile: "
		       "%s profile mismatch",
		       dm_device_name(t->md),
		       template_disk->disk_name);
		return 1;
	}

	/* Preserve existing integrity profile */
	t->integrity_supported = true;
	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Mike Snitzer
84
67.20%
2
40.00%
Martin K. Petersen
26
20.80%
2
40.00%
Will Drewry
15
12.00%
1
20.00%
Total
125
100.00%
5
100.00%

/*
 * Prepares the table for use by building the indices,
 * setting the type, and allocating mempools.
 */


int dm_table_complete(struct dm_table *t)
{
	int r;

	r = dm_table_determine_type(t);
	if (r) {
		DMERR("unable to determine table type");
		return r;
	}

	r = dm_table_build_index(t);
	if (r) {
		DMERR("unable to build btrees");
		return r;
	}

	r = dm_table_register_integrity(t);
	if (r) {
		DMERR("could not register integrity profile.");
		return r;
	}

	r = dm_table_alloc_md_mempools(t, t->md);
	if (r)
		DMERR("unable to allocate mempools");

	return r;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Will Drewry
92
92.93%
1
25.00%
Mike Snitzer
6
6.06%
2
50.00%
Martin K. Petersen
1
1.01%
1
25.00%
Total
99
100.00%
4
100.00%

static DEFINE_MUTEX(_event_lock);


void dm_table_event_callback(struct dm_table *t,
			     void (*fn)(void *), void *context)
{
	mutex_lock(&_event_lock);
	t->event_fn = fn;
	t->event_context = context;
	mutex_unlock(&_event_lock);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Andrew Morton
46
95.83%
1
50.00%
Arjan van de Ven
2
4.17%
1
50.00%
Total
48
100.00%
2
100.00%



void dm_table_event(struct dm_table *t)
{
	/*
         * You can no longer call dm_table_event() from interrupt
         * context, use a bottom half instead.
         */
	BUG_ON(in_interrupt());

	mutex_lock(&_event_lock);
	if (t->event_fn)
		t->event_fn(t->event_context);
	mutex_unlock(&_event_lock);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Andrew Morton
26
59.09%
2
50.00%
Alan Cox
16
36.36%
1
25.00%
Arjan van de Ven
2
4.55%
1
25.00%
Total
44
100.00%
4
100.00%


EXPORT_SYMBOL(dm_table_event);



sector_t dm_table_get_size(struct dm_table *t)
{
	return t->num_targets ? (t->highs[t->num_targets - 1] + 1) : 0;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Alan Cox
32
100.00%
1
100.00%
Total
32
100.00%
1
100.00%


EXPORT_SYMBOL(dm_table_get_size);



struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index)
{
	if (index >= t->num_targets)
		return NULL;

	return t->targets + index;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Alan Cox
32
94.12%
1
33.33%
Joe Thornber
1
2.94%
1
33.33%
Milan Broz
1
2.94%
1
33.33%
Total
34
100.00%
3
100.00%

/*
 * Search the btree for the correct target.
 *
 * Caller should check returned pointer with dm_target_is_valid()
 * to trap I/O beyond end of device.
 */


struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector)
{
	unsigned int l, n = 0, k = 0;
	sector_t *node;

	for (l = 0; l < t->depth; l++) {
		n = get_child(n, k);
		node = get_node(t, l, n);

		for (k = 0; k < KEYS_PER_NODE; k++)
			if (node[k] >= sector)
				break;
	}

	return &t->targets[(KEYS_PER_NODE * n) + k];
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Alan Cox
105
99.06%
1
50.00%
Joe Thornber
1
0.94%
1
50.00%
Total
106
100.00%
2
100.00%



static int count_device(struct dm_target *ti, struct dm_dev *dev,
			sector_t start, sector_t len, void *data)
{
	unsigned *num_devices = data;

	(*num_devices)++;

	return 0;
}

Contributors
Person
Tokens
Prop
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CommitProp
Mike Snitzer
41
100.00%
1
100.00%
Total
41
100.00%
1
100.00%

/*
 * Check whether a table has no data devices attached using each
 * target's iterate_devices method.
 * Returns false if the result is unknown because a target doesn't
 * support iterate_devices.
 */


bool dm_table_has_no_data_devices(struct dm_table *table)
{
	struct dm_target *uninitialized_var(ti);
	unsigned i = 0, num_devices = 0;

	while (i < dm_table_get_num_targets(table)) {
		ti = dm_table_get_target(table, i++);

		if (!ti->type->iterate_devices)
			return false;

		ti->type->iterate_devices(ti, count_device, &num_devices);
		if (num_devices)
			return false;
	}

	return true;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Mike Snitzer
84
100.00%
1
100.00%
Total
84
100.00%
1
100.00%

/*
 * Establish the new table's queue_limits and validate them.
 */


int dm_calculate_queue_limits(struct dm_table *table,
			      struct queue_limits *limits)
{
	struct dm_target *uninitialized_var(ti);
	struct queue_limits ti_limits;
	unsigned i = 0;

	blk_set_stacking_limits(limits);

	while (i < dm_table_get_num_targets(table)) {
		blk_set_stacking_limits(&ti_limits);

		ti = dm_table_get_target(table, i++);

		if (!ti->type->iterate_devices)
			goto combine_limits;

		/*
                 * Combine queue limits of all the devices this target uses.
                 */
		ti->type->iterate_devices(ti, dm_set_device_limits,
					  &ti_limits);

		/* Set I/O hints portion of queue limits */
		if (ti->type->io_hints)
			ti->type->io_hints(ti, &ti_limits);

		/*
                 * Check each device area is consistent with the target's
                 * overall queue limits.
                 */
		if (ti->type->iterate_devices(ti, device_area_is_invalid,
					      &ti_limits))
			return -EINVAL;

combine_limits:
		/*
                 * Merge this target's queue limits into the overall limits
                 * for the table.
                 */
		if (blk_stack_limits(limits, &ti_limits, 0) < 0)
			DMWARN("%s: adding target device "
			       "(start sect %llu len %llu) "
			       "caused an alignment inconsistency",
			       dm_device_name(table->md),
			       (unsigned long long) ti->begin,
			       (unsigned long long) ti->len);
	}

	return validate_hardware_logical_block_alignment(table, limits);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Mike Snitzer
185
97.37%
2
40.00%
Martin K. Petersen
4
2.11%
2
40.00%
Mikulas Patocka
1
0.53%
1
20.00%
Total
190
100.00%
5
100.00%

/*
 * Verify that all devices have an integrity profile that matches the
 * DM device's registered integrity profile.  If the profiles don't
 * match then unregister the DM device's integrity profile.
 */


static void dm_table_verify_integrity(struct dm_table *t)
{
	struct gendisk *template_disk = NULL;

	if (t->integrity_supported) {
		/*
                 * Verify that the original integrity profile
                 * matches all the devices in this table.
                 */
		template_disk = dm_table_get_integrity_disk(t);
		if (template_disk &&
		    blk_integrity_compare(dm_disk(t->md), template_disk) >= 0)
			return;
	}

	if (integrity_profile_exists(dm_disk(t->md))) {
		DMWARN("%s: unable to establish an integrity profile",
		       dm_device_name(t->md));
		blk_integrity_unregister(dm_disk(t->md));
	}
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Martin K. Petersen
64
71.91%
2
50.00%
Mike Snitzer
25
28.09%
2
50.00%
Total
89
100.00%
4
100.00%



static int device_flush_capable(struct dm_target *ti, struct dm_dev *dev,
				sector_t start, sector_t len, void *data)
{
	unsigned long flush = (unsigned long) data;
	struct request_queue *q = bdev_get_queue(dev->bdev);

	return q && (q->queue_flags & flush);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Mike Snitzer
56
94.92%
1
50.00%
Jens Axboe
3
5.08%
1
50.00%
Total
59
100.00%
2
100.00%



static bool dm_table_supports_flush(struct dm_table *t, unsigned long flush)
{
	struct dm_target *ti;
	unsigned i = 0;

	/*
         * Require at least one underlying device to support flushes.
         * t->devices includes internal dm devices such as mirror logs
         * so we need to use iterate_devices here, which targets
         * supporting flushes must provide.
         */
	while (i < dm_table_get_num_targets(t)) {
		ti = dm_table_get_target(t, i++);

		if (!ti->num_flush_bios)
			continue;

		if (ti->flush_supported)
			return true;

		if (ti->type->iterate_devices &&
		    ti->type->iterate_devices(ti, device_flush_capable, (void *) flush))
			return true;
	}

	return false;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Mike Snitzer
78
82.11%
1
20.00%
Joe Thornber
8
8.42%
1
20.00%
Jens Axboe
5
5.26%
1
20.00%
Joe Perches
3
3.16%
1
20.00%
Alasdair G. Kergon
1
1.05%
1
20.00%
Total
95
100.00%
5
100.00%



static bool dm_table_discard_zeroes_data(struct dm_table *t)
{
	struct dm_target *ti;
	unsigned i = 0;

	/* Ensure that all targets supports discard_zeroes_data. */
	while (i < dm_table_get_num_targets(t)) {
		ti = dm_table_get_target(t, i++);

		if (ti->discard_zeroes_data_unsupported)
			return false;
	}

	return true;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Milan Broz
53
96.36%
1
50.00%
Joe Perches
2
3.64%
1
50.00%
Total
55
100.00%
2
100.00%



static int device_is_nonrot(struct dm_target *ti, struct dm_dev *dev,
			    sector_t start, sector_t len, void *data)
{
	struct request_queue *q = bdev_get_queue(dev->bdev);

	return q && blk_queue_nonrot(q);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Mandeep Singh Baines
46
100.00%
1
100.00%
Total
46
100.00%
1
100.00%



static int device_is_not_random(struct dm_target *ti, struct dm_dev *dev,
			     sector_t start, sector_t len, void *data)
{
	struct request_queue *q = bdev_get_queue(dev->bdev);

	return q && !blk_queue_add_random(q);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Milan Broz
47
100.00%
1
100.00%
Total
47
100.00%
1
100.00%



static int queue_supports_sg_merge(struct dm_target *ti, struct dm_dev *dev,
				   sector_t start, sector_t len, void *data)
{
	struct request_queue *q = bdev_get_queue(dev->bdev);

	return q && !test_bit(QUEUE_FLAG_NO_SG_MERGE, &q->queue_flags);
}

Contributors
Person
Tokens
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Commits
CommitProp
Jeff Moyer
52
100.00%
1
100.00%
Total
52
100.00%
1
100.00%



static bool dm_table_all_devices_attribute(struct dm_table *t,
					   iterate_devices_callout_fn func)
{
	struct dm_target *ti;
	unsigned i = 0;

	while (i < dm_table_get_num_targets(t)) {
		ti = dm_table_get_target(t, i++);

		if (!ti->type->iterate_devices ||
		    !ti->type->iterate_devices(ti, func, NULL))
			return false;
	}

	return true;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Mandeep Singh Baines
67
90.54%
1
33.33%
Milan Broz
5
6.76%
1
33.33%
Joe Perches
2
2.70%
1
33.33%
Total
74
100.00%
3
100.00%



static int device_not_write_same_capable(struct dm_target *ti, struct dm_dev *dev,
					 sector_t start, sector_t len, void *data)
{
	struct request_queue *q = bdev_get_queue(dev->bdev);

	return q && !q->limits.max_write_same_sectors;
}

Contributors
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Tokens
Prop
Commits
CommitProp
Mike Snitzer
48
100.00%
1
100.00%
Total
48
100.00%
1
100.00%



static bool dm_table_supports_write_same(struct dm_table *t)
{
	struct dm_target *ti;
	unsigned i = 0;

	while (i < dm_table_get_num_targets(t)) {
		ti = dm_table_get_target(t, i++);

		if (!ti->num_write_same_bios)
			return false;

		if (!ti->type->iterate_devices ||
		    ti->type->iterate_devices(ti, device_not_write_same_capable, NULL))
			return false;
	}

	return true;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Mike Snitzer
79
98.75%
1
50.00%
Alasdair G. Kergon
1
1.25%
1
50.00%
Total
80
100.00%
2
100.00%



static int device_discard_capable(struct dm_target *ti, struct dm_dev *dev,
				  sector_t start, sector_t len, void *data)
{
	struct request_queue *q = bdev_get_queue(dev->bdev);

	return q && blk_queue_discard(q);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Mikulas Patocka
46
100.00%
1
100.00%
Total
46
100.00%
1
100.00%



static bool dm_table_supports_discards(struct dm_table *t)
{
	struct dm_target *ti;
	unsigned i = 0;

	/*
         * Unless any target used by the table set discards_supported,
         * require at least one underlying device to support discards.
         * t->devices includes internal dm devices such as mirror logs
         * so we need to use iterate_devices here, which targets
         * supporting discard selectively must provide.
         */
	while (i < dm_table_get_num_targets(t)) {
		ti = dm_table_get_target(t, i++);

		if (!ti->num_discard_bios)
			continue;

		if (ti->discards_supported)
			return true;

		if (ti->type->iterate_devices &&
		    ti->type->iterate_devices(ti, device_discard_capable, NULL))
			return true;
	}

	return false;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Mikulas Patocka
84
96.55%
1
50.00%
Joe Perches
3
3.45%
1
50.00%
Total
87
100.00%
2
100.00%



void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
			       struct queue_limits *limits)
{
	bool wc = false, fua = false;

	/*
         * Copy table's limits to the DM device's request_queue
         */
	q->limits = *limits;

	if (!dm_table_supports_discards(t))
		queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, q);
	else
		queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);

	if (dm_table_supports_flush(t, (1UL << QUEUE_FLAG_WC))) {
		wc = true;
		if (dm_table_supports_flush(t, (1UL << QUEUE_FLAG_FUA)))
			fua = true;
	}
	blk_queue_write_cache(q, wc, fua);

	if (!dm_table_discard_zeroes_data(t))
		q->limits.discard_zeroes_data = 0;

	/* Ensure that all underlying devices are non-rotational. */
	if (dm_table_all_devices_attribute(t, device_is_nonrot))
		queue_flag_set_unlocked(QUEUE_FLAG_NONROT, q);
	else
		queue_flag_clear_unlocked(QUEUE_FLAG_NONROT, q);

	if (!dm_table_supports_write_same(t))
		q->limits.max_write_same_sectors = 0;

	if (dm_table_all_devices_attribute(t, queue_supports_sg_merge))
		queue_flag_clear_unlocked(QUEUE_FLAG_NO_SG_MERGE, q);
	else
		queue_flag_set_unlocked(QUEUE_FLAG_NO_SG_MERGE, q);

	dm_table_verify_integrity(t);

	/*
         * Determine whether or not this queue's I/O timings contribute
         * to the entropy pool, Only request-based targets use this.
         * Clear QUEUE_FLAG_ADD_RANDOM if any underlying device does not
         * have it set.
         */
	if (blk_queue_add_random(q) && dm_table_all_devices_attribute(t, device_is_not_random))
		queue_flag_clear_unlocked(QUEUE_FLAG_ADD_RANDOM, q);

	/*
         * QUEUE_FLAG_STACKABLE must be set after all queue settings are
         * visible to other CPUs because, once the flag is set, incoming bios
         * are processed by request-based dm, which refers to the queue
         * settings.
         * Until the flag set, bios are passed to bio-based dm and queued to
         * md->deferred where queue settings are not needed yet.
         * Those bios are passed to request-based dm at the resume time.
         */
	smp_mb();
	if (dm_table_request_based(t))
		queue_flag_set_unlocked(QUEUE_FLAG_STACKABLE, q);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Mike Snitzer
72
31.17%
6
33.33%
Milan Broz
42
18.18%
2
11.11%
Jens Axboe
27
11.69%
2
11.11%
Jeff Moyer
24
10.39%
1
5.56%
Mandeep Singh Baines
21
9.09%
1
5.56%
Kiyoshi Ueda
18
7.79%
1
5.56%
Alan Cox
18
7.79%
1
5.56%
Martin K. Petersen
5
2.16%
2
11.11%
Neil Brown
2
0.87%
1
5.56%
Vasily Averin
2
0.87%
1
5.56%
Total
231
100.00%
18
100.00%



unsigned int dm_table_get_num_targets(struct dm_table *t)
{
	return t->num_targets;
}

Contributors
Person
Tokens
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Commits
CommitProp
Alan Cox
16
100.00%
1
100.00%
Total
16
100.00%
1
100.00%



struct list_head *dm_table_get_devices(struct dm_table *t)
{
	return &t->devices;
}

Contributors
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Tokens
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CommitProp
Alan Cox
18
100.00%
1
100.00%
Total
18
100.00%
1
100.00%



fmode_t dm_table_get_mode(struct dm_table *t)
{
	return t->mode;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Alan Cox
14
93.33%
1
50.00%
Al Viro
1
6.67%
1
50.00%
Total
15
100.00%
2
100.00%


EXPORT_SYMBOL(dm_table_get_mode);


enum suspend_mode {
	
PRESUSPEND,
	
PRESUSPEND_UNDO,
	
POSTSUSPEND,
};



static void suspend_targets(struct dm_table *t, enum suspend_mode mode)
{
	int i = t->num_targets;
	struct dm_target *ti = t->targets;

	while (i--) {
		switch (mode) {
		case PRESUSPEND:
			if (ti->type->presuspend)
				ti->type->presuspend(ti);
			break;
		case PRESUSPEND_UNDO:
			if (ti->type->presuspend_undo)
				ti->type->presuspend_undo(ti);
			break;
		case POSTSUSPEND:
			if (ti->type->postsuspend)
				ti->type->postsuspend(ti);
			break;
		}
		ti++;
	}
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Mike Snitzer
39
35.45%
1
33.33%
Joe Thornber
37
33.64%
1
33.33%
Alasdair G. Kergon
34
30.91%
1
33.33%
Total
110
100.00%
3
100.00%



void dm_table_presuspend_targets(struct dm_table *t)
{
	if (!t)
		return;

	suspend_targets(t, PRESUSPEND);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Alasdair G. Kergon
19
82.61%
2
66.67%
Mike Snitzer
4
17.39%
1
33.33%
Total
23
100.00%
3
100.00%



void dm_table_presuspend_undo_targets(struct dm_table *t)
{
	if (!t)
		return;

	suspend_targets(t, PRESUSPEND_UNDO);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Mike Snitzer
20
86.96%
1
33.33%
Alasdair G. Kergon
2
8.70%
1
33.33%
Adrian Bunk
1
4.35%
1
33.33%
Total
23
100.00%
3
100.00%



void dm_table_postsuspend_targets(struct dm_table *t)
{
	if (!t)
		return;

	suspend_targets(t, POSTSUSPEND);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Alasdair G. Kergon
20
86.96%
2
40.00%
Adrian Bunk
1
4.35%
1
20.00%
Mike Snitzer
1
4.35%
1
20.00%
Joe Thornber
1
4.35%
1
20.00%
Total
23
100.00%
5
100.00%



int dm_table_resume_targets(struct dm_table *t)
{
	int i, r = 0;

	for (i = 0; i < t->num_targets; i++) {
		struct dm_target *ti = t->targets + i;

		if (!ti->type->preresume)
			continue;

		r = ti->type->preresume(ti);
		if (r) {
			DMERR("%s: %s: preresume failed, error = %d",
			      dm_device_name(t->md), ti->type->name, r);
			return r;
		}
	}

	for (i = 0; i < t->num_targets; i++) {
		struct dm_target *ti = t->targets + i;

		if (ti->type->resume)
			ti->type->resume(ti);
	}

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Milan Broz
64
44.76%
1
33.33%
Joe Thornber
57
39.86%
1
33.33%
Mike Snitzer
22
15.38%
1
33.33%
Total
143
100.00%
3
100.00%



void dm_table_add_target_callbacks(struct dm_table *t, struct dm_target_callbacks *cb)
{
	list_add(&cb->list, &t->target_callbacks);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Neil Brown
28
100.00%
1
100.00%
Total
28
100.00%
1
100.00%


EXPORT_SYMBOL_GPL(dm_table_add_target_callbacks);



int dm_table_any_congested(struct dm_table *t, int bdi_bits)
{
	struct dm_dev_internal *dd;
	struct list_head *devices = dm_table_get_devices(t);
	struct dm_target_callbacks *cb;
	int r = 0;

	list_for_each_entry(dd, devices, list) {
		struct request_queue *q = bdev_get_queue(dd->dm_dev->bdev);
		char b[BDEVNAME_SIZE];

		if (likely(q))
			r |= bdi_congested(q->backing_dev_info, bdi_bits);
		else
			DMWARN_LIMIT("%s: any_congested: nonexistent device %s",
				     dm_device_name(t->md),
				     bdevname(dd->dm_dev->bdev, b));
	}

	list_for_each_entry(cb, &t->target_callbacks, list)
		if (cb->congested_fn)
			r |= cb->congested_fn(cb, bdi_bits);

	return r;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Andrew Morton
52
37.68%
1
14.29%
Alasdair G. Kergon
36
26.09%
1
14.29%
Neil Brown
30
21.74%
1
14.29%
Paul Jimenez
14
10.14%
1
14.29%
Benjamin Marzinski
2
1.45%
1
14.29%
Jens Axboe
2
1.45%
1
14.29%
Mikulas Patocka
2
1.45%
1
14.29%
Total
138
100.00%
7
100.00%



struct mapped_device *dm_table_get_md(struct dm_table *t)
{
	return t->md;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Mike Anderson
17
100.00%
1
100.00%
Total
17
100.00%
1
100.00%


EXPORT_SYMBOL(dm_table_get_md);



void dm_table_run_md_queue_async(struct dm_table *t)
{
	struct mapped_device *md;
	struct request_queue *queue;
	unsigned long flags;

	if (!dm_table_request_based(t))
		return;

	md = dm_table_get_md(t);
	queue = dm_get_md_queue(md);
	if (queue) {
		if (queue->mq_ops)
			blk_mq_run_hw_queues(queue, true);
		else {
			spin_lock_irqsave(queue->queue_lock, flags);
			blk_run_queue_async(queue);
			spin_unlock_irqrestore(queue->queue_lock, flags);
		}
	}
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Mike Snitzer
92
100.00%
2
100.00%
Total
92
100.00%
2
100.00%


EXPORT_SYMBOL(dm_table_run_md_queue_async);

Overall Contributors
Person
Tokens
Prop
Commits
CommitProp
Mike Snitzer
2312
31.69%
36
27.48%
Alan Cox
1964
26.92%
2
1.53%
Alasdair G. Kergon
363
4.98%
12
9.16%
Kiyoshi Ueda
290
3.97%
1
0.76%
Milan Broz
283
3.88%
5
3.82%
Mikulas Patocka
269
3.69%
11
8.40%
Andrew Morton
217
2.97%
11
8.40%
Toshi Kani
194
2.66%
1
0.76%
Joe Thornber
186
2.55%
9
6.87%
Will Drewry
147
2.01%
1
0.76%
Kevin Corry
146
2.00%
2
1.53%
Martin K. Petersen
137
1.88%
6
4.58%
Mandeep Singh Baines
134
1.84%
1
0.76%
Benjamin Marzinski
132
1.81%
1
0.76%
Neil Brown
80
1.10%
3
2.29%
Jeff Moyer
76
1.04%
1
0.76%
DingXiang
66
0.90%
1
0.76%
Jun'ichi Nomura
49
0.67%
3
2.29%
Bart Van Assche
44
0.60%
2
1.53%
Mike Anderson
42
0.58%
2
1.53%
Jens Axboe
39
0.53%
3
2.29%
tang.junhui
27
0.37%
1
0.76%
Paul Jimenez
22
0.30%
1
0.76%
David Teigland
15
0.21%
1
0.76%
Al Viro
12
0.16%
2
1.53%
Joe Perches
11
0.15%
2
1.53%
Jonathan E Brassow
9
0.12%
1
0.76%
Arjan van de Ven
8
0.11%
1
0.76%
André Goddard Rosa
6
0.08%
1
0.76%
Dan Ehrenberg
6
0.08%
1
0.76%
Eric Sesterhenn / Snakebyte
3
0.04%
1
0.76%
Adrian Bunk
2
0.03%
1
0.76%
Vasily Averin
2
0.03%
1
0.76%
Dmitriy Monakhov
1
0.01%
1
0.76%
Arun Sharma
1
0.01%
1
0.76%
Bryn M. Reeves
1
0.01%
1
0.76%
Total
7296
100.00%
131
100.00%
Directory: drivers/md

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