dm-table.c 46.9 KB
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/*
 * Copyright (C) 2001 Sistina Software (UK) Limited.
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 * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
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 *
 * This file is released under the GPL.
 */

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#include "dm-core.h"
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#include <linux/module.h>
#include <linux/vmalloc.h>
#include <linux/blkdev.h>
#include <linux/namei.h>
#include <linux/ctype.h>
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#include <linux/string.h>
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#include <linux/slab.h>
#include <linux/interrupt.h>
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#include <linux/mutex.h>
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#include <linux/delay.h>
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#include <linux/atomic.h>
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#include <linux/blk-mq.h>
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#include <linux/mount.h>
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#include <linux/dax.h>
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#define DM_MSG_PREFIX "table"

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#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 {
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	struct mapped_device *md;
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	enum dm_queue_mode type;
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	/* 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;

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	struct target_type *immutable_target_type;
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	bool integrity_supported:1;
	bool singleton:1;
	bool all_blk_mq:1;
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	unsigned integrity_added:1;
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	/*
	 * Indicates the rw permissions for the new logical
	 * device.  This should be a combination of FMODE_READ
	 * and FMODE_WRITE.
	 */
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	fmode_t mode;
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	/* 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;
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	struct dm_md_mempools *mempools;
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	struct list_head target_callbacks;
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};

/*
 * 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;
}

/*
 * 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;
}

/*
 * 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);
}

/*
 * 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];
}

/*
 * 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;
}

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;
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	addr = vzalloc(size);
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	return addr;
}
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EXPORT_SYMBOL(dm_vcalloc);
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/*
 * 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.
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	 * Append an empty entry to catch sectors beyond the end of
	 * the device.
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	 */
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	n_highs = (sector_t *) dm_vcalloc(num + 1, sizeof(struct dm_target) +
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					  sizeof(sector_t));
	if (!n_highs)
		return -ENOMEM;

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

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

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

	return 0;
}

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int dm_table_create(struct dm_table **result, fmode_t mode,
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		    unsigned num_targets, struct mapped_device *md)
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{
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	struct dm_table *t = kzalloc(sizeof(*t), GFP_KERNEL);
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	if (!t)
		return -ENOMEM;

	INIT_LIST_HEAD(&t->devices);
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	INIT_LIST_HEAD(&t->target_callbacks);
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	if (!num_targets)
		num_targets = KEYS_PER_NODE;

	num_targets = dm_round_up(num_targets, KEYS_PER_NODE);

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

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

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

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static void free_devices(struct list_head *devices, struct mapped_device *md)
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{
	struct list_head *tmp, *next;

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	list_for_each_safe(tmp, next, devices) {
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		struct dm_dev_internal *dd =
		    list_entry(tmp, struct dm_dev_internal, list);
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		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);
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		kfree(dd);
	}
}

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

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	if (!t)
		return;

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	/* free the indexes */
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	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 */
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	free_devices(&t->devices, t->md);
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	dm_free_md_mempools(t->mempools);

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	kfree(t);
}

/*
 * See if we've already got a device in the list.
 */
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static struct dm_dev_internal *find_device(struct list_head *l, dev_t dev)
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{
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	struct dm_dev_internal *dd;
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	list_for_each_entry (dd, l, list)
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		if (dd->dm_dev->bdev->bd_dev == dev)
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			return dd;

	return NULL;
}

/*
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 * If possible, this checks an area of a destination device is invalid.
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 */
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static int device_area_is_invalid(struct dm_target *ti, struct dm_dev *dev,
				  sector_t start, sector_t len, void *data)
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{
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	struct request_queue *q;
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	struct queue_limits *limits = data;
	struct block_device *bdev = dev->bdev;
	sector_t dev_size =
		i_size_read(bdev->bd_inode) >> SECTOR_SHIFT;
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	unsigned short logical_block_size_sectors =
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		limits->logical_block_size >> SECTOR_SHIFT;
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	char b[BDEVNAME_SIZE];
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	/*
	 * 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;
	}

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	if (!dev_size)
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		return 0;
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	if ((start >= dev_size) || (start + len > dev_size)) {
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		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);
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		return 1;
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	}

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	/*
	 * If the target is mapped to zoned block device(s), check
	 * that the zones are not partially mapped.
	 */
	if (bdev_zoned_model(bdev) != BLK_ZONED_NONE) {
		unsigned int zone_sectors = bdev_zone_sectors(bdev);

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

		/*
		 * Note: The last zone of a zoned block device may be smaller
		 * than other zones. So for a target mapping the end of a
		 * zoned block device with such a zone, len would not be zone
		 * aligned. We do not allow such last smaller zone to be part
		 * of the mapping here to ensure that mappings with multiple
		 * devices do not end up with a smaller zone in the middle of
		 * the sector range.
		 */
		if (len & (zone_sectors - 1)) {
			DMWARN("%s: len=%llu not aligned to h/w zone size %u of %s",
			       dm_device_name(ti->table->md),
			       (unsigned long long)len,
			       zone_sectors, bdevname(bdev, b));
			return 1;
		}
	}

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	if (logical_block_size_sectors <= 1)
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		return 0;
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	if (start & (logical_block_size_sectors - 1)) {
		DMWARN("%s: start=%llu not aligned to h/w "
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		       "logical block size %u of %s",
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		       dm_device_name(ti->table->md),
		       (unsigned long long)start,
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		       limits->logical_block_size, bdevname(bdev, b));
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		return 1;
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	}

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

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	return 0;
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}

/*
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 * This upgrades the mode on an already open dm_dev, being
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 * careful to leave things as they were if we fail to reopen the
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 * device and not to touch the existing bdev field in case
 * it is accessed concurrently inside dm_table_any_congested().
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 */
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static int upgrade_mode(struct dm_dev_internal *dd, fmode_t new_mode,
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			struct mapped_device *md)
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{
	int r;
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	struct dm_dev *old_dev, *new_dev;
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	old_dev = dd->dm_dev;
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	r = dm_get_table_device(md, dd->dm_dev->bdev->bd_dev,
				dd->dm_dev->mode | new_mode, &new_dev);
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	if (r)
		return r;
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	dd->dm_dev = new_dev;
	dm_put_table_device(md, old_dev);
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	return 0;
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}

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/*
 * Convert the path to a device
 */
dev_t dm_get_dev_t(const char *path)
{
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	dev_t dev;
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	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;
}
EXPORT_SYMBOL_GPL(dm_get_dev_t);

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/*
 * Add a device to the list, or just increment the usage count if
 * it's already present.
 */
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int dm_get_device(struct dm_target *ti, const char *path, fmode_t mode,
		  struct dm_dev **result)
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{
	int r;
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	dev_t dev;
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	struct dm_dev_internal *dd;
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	struct dm_table *t = ti->table;
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	BUG_ON(!t);
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	dev = dm_get_dev_t(path);
	if (!dev)
		return -ENODEV;
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	dd = find_device(&t->devices, dev);
	if (!dd) {
		dd = kmalloc(sizeof(*dd), GFP_KERNEL);
		if (!dd)
			return -ENOMEM;

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

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

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

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	*result = dd->dm_dev;
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	return 0;
}
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EXPORT_SYMBOL(dm_get_device);
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static int dm_set_device_limits(struct dm_target *ti, struct dm_dev *dev,
				sector_t start, sector_t len, void *data)
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{
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	struct queue_limits *limits = data;
	struct block_device *bdev = dev->bdev;
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	struct request_queue *q = bdev_get_queue(bdev);
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	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));
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		return 0;
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	}
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	if (bdev_stack_limits(limits, bdev, start) < 0)
		DMWARN("%s: adding target device %s caused an alignment inconsistency: "
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		       "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,
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		       (unsigned long long) start << SECTOR_SHIFT);
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	limits->zoned = blk_queue_zoned_model(q);

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	return 0;
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}
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/*
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 * Decrement a device's use count and remove it if necessary.
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 */
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void dm_put_device(struct dm_target *ti, struct dm_dev *d)
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{
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	int found = 0;
	struct list_head *devices = &ti->table->devices;
	struct dm_dev_internal *dd;
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	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;
	}
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	if (atomic_dec_and_test(&dd->count)) {
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		dm_put_table_device(ti->table->md, d);
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		list_del(&dd->list);
		kfree(dd);
	}
}
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EXPORT_SYMBOL(dm_put_device);
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/*
 * 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));
}

/*
 * Used to dynamically allocate the arg array.
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 *
 * 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.
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 */
static char **realloc_argv(unsigned *array_size, char **old_argv)
{
	char **argv;
	unsigned new_size;
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	gfp_t gfp;
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	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);
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	if (argv) {
		memcpy(argv, old_argv, *array_size * sizeof(*argv));
		*array_size = new_size;
	}

	kfree(old_argv);
	return argv;
}

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

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

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

636 637 638 639 640 641 642
/*
 * 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.
 */
643 644
static int validate_hardware_logical_block_alignment(struct dm_table *table,
						 struct queue_limits *limits)
645 646 647 648 649 650
{
	/*
	 * This function uses arithmetic modulo the logical_block_size
	 * (in units of 512-byte sectors).
	 */
	unsigned short device_logical_block_size_sects =
651
		limits->logical_block_size >> SECTOR_SHIFT;
652 653 654 655 656 657 658 659 660 661 662 663 664

	/*
	 * 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);
665
	struct queue_limits ti_limits;
666
	unsigned i;
667 668 669 670

	/*
	 * Check each entry in the table in turn.
	 */
671 672
	for (i = 0; i < dm_table_get_num_targets(table); i++) {
		ti = dm_table_get_target(table, i);
673

674
		blk_set_stacking_limits(&ti_limits);
675 676 677 678 679 680

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

681 682 683 684 685
		/*
		 * If the remaining sectors fall entirely within this
		 * table entry are they compatible with its logical_block_size?
		 */
		if (remaining < ti->len &&
686
		    remaining & ((ti_limits.logical_block_size >>
687 688 689 690 691 692 693 694 695 696 697 698
				  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) "
699
		       "not aligned to h/w logical block size %u",
700 701 702
		       dm_device_name(table->md), i,
		       (unsigned long long) ti->begin,
		       (unsigned long long) ti->len,
703
		       limits->logical_block_size);
704 705 706 707 708 709
		return -EINVAL;
	}

	return 0;
}

L
Linus Torvalds 已提交
710 711 712 713 714 715 716
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;

717 718 719 720 721 722
	if (t->singleton) {
		DMERR("%s: target type %s must appear alone in table",
		      dm_device_name(t->md), t->targets->type->name);
		return -EINVAL;
	}

723
	BUG_ON(t->num_targets >= t->num_allocated);
L
Linus Torvalds 已提交
724 725 726 727 728

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

	if (!len) {
729
		DMERR("%s: zero-length target", dm_device_name(t->md));
L
Linus Torvalds 已提交
730 731 732 733 734
		return -EINVAL;
	}

	tgt->type = dm_get_target_type(type);
	if (!tgt->type) {
735
		DMERR("%s: %s: unknown target type", dm_device_name(t->md), type);
L
Linus Torvalds 已提交
736 737 738
		return -EINVAL;
	}

739 740
	if (dm_target_needs_singleton(tgt->type)) {
		if (t->num_targets) {
741 742
			tgt->error = "singleton target type must appear alone in table";
			goto bad;
743
		}
744
		t->singleton = true;
745 746
	}

747
	if (dm_target_always_writeable(tgt->type) && !(t->mode & FMODE_WRITE)) {
748 749
		tgt->error = "target type may not be included in a read-only table";
		goto bad;
750 751
	}

752 753
	if (t->immutable_target_type) {
		if (t->immutable_target_type != tgt->type) {
754 755
			tgt->error = "immutable target type cannot be mixed with other target types";
			goto bad;
756 757 758
		}
	} else if (dm_target_is_immutable(tgt->type)) {
		if (t->num_targets) {
759 760
			tgt->error = "immutable target type cannot be mixed with other target types";
			goto bad;
761 762 763 764
		}
		t->immutable_target_type = tgt->type;
	}

765 766 767
	if (dm_target_has_integrity(tgt->type))
		t->integrity_added = 1;

L
Linus Torvalds 已提交
768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793
	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;

794 795
	if (!tgt->num_discard_bios && tgt->discards_supported)
		DMWARN("%s: %s: ignoring discards_supported because num_discard_bios is zero.",
M
Mike Snitzer 已提交
796
		       dm_device_name(t->md), type);
M
Mike Snitzer 已提交
797

L
Linus Torvalds 已提交
798 799 800
	return 0;

 bad:
801
	DMERR("%s: %s: %s", dm_device_name(t->md), type, tgt->error);
L
Linus Torvalds 已提交
802 803 804 805
	dm_put_target_type(tgt->type);
	return r;
}

806 807 808
/*
 * Target argument parsing helpers.
 */
E
Eric Biggers 已提交
809 810
static int validate_next_arg(const struct dm_arg *arg,
			     struct dm_arg_set *arg_set,
811 812 813
			     unsigned *value, char **error, unsigned grouped)
{
	const char *arg_str = dm_shift_arg(arg_set);
814
	char dummy;
815 816

	if (!arg_str ||
817
	    (sscanf(arg_str, "%u%c", value, &dummy) != 1) ||
818 819 820 821 822 823 824 825 826 827
	    (*value < arg->min) ||
	    (*value > arg->max) ||
	    (grouped && arg_set->argc < *value)) {
		*error = arg->error;
		return -EINVAL;
	}

	return 0;
}

E
Eric Biggers 已提交
828
int dm_read_arg(const struct dm_arg *arg, struct dm_arg_set *arg_set,
829 830 831 832 833 834
		unsigned *value, char **error)
{
	return validate_next_arg(arg, arg_set, value, error, 0);
}
EXPORT_SYMBOL(dm_read_arg);

E
Eric Biggers 已提交
835
int dm_read_arg_group(const struct dm_arg *arg, struct dm_arg_set *arg_set,
836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864
		      unsigned *value, char **error)
{
	return validate_next_arg(arg, arg_set, value, error, 1);
}
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;
}
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;
}
EXPORT_SYMBOL(dm_consume_args);

865
static bool __table_type_bio_based(enum dm_queue_mode table_type)
866 867 868 869 870
{
	return (table_type == DM_TYPE_BIO_BASED ||
		table_type == DM_TYPE_DAX_BIO_BASED);
}

871
static bool __table_type_request_based(enum dm_queue_mode table_type)
872 873 874 875 876
{
	return (table_type == DM_TYPE_REQUEST_BASED ||
		table_type == DM_TYPE_MQ_REQUEST_BASED);
}

877
void dm_table_set_type(struct dm_table *t, enum dm_queue_mode type)
878 879 880 881 882
{
	t->type = type;
}
EXPORT_SYMBOL_GPL(dm_table_set_type);

883 884 885 886 887 888 889 890 891 892 893
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);
}

static bool dm_table_supports_dax(struct dm_table *t)
{
	struct dm_target *ti;
894
	unsigned i;
895 896

	/* Ensure that all targets support DAX. */
897 898
	for (i = 0; i < dm_table_get_num_targets(t); i++) {
		ti = dm_table_get_target(t, i);
899 900 901 902 903 904 905 906 907 908 909 910

		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;
}

911
static int dm_table_determine_type(struct dm_table *t)
K
Kiyoshi Ueda 已提交
912 913
{
	unsigned i;
914
	unsigned bio_based = 0, request_based = 0, hybrid = 0;
915
	unsigned sq_count = 0, mq_count = 0;
K
Kiyoshi Ueda 已提交
916 917
	struct dm_target *tgt;
	struct dm_dev_internal *dd;
918
	struct list_head *devices = dm_table_get_devices(t);
919
	enum dm_queue_mode live_md_type = dm_get_md_type(t->md);
K
Kiyoshi Ueda 已提交
920

921 922 923 924
	if (t->type != DM_TYPE_NONE) {
		/* target already set the table's type */
		if (t->type == DM_TYPE_BIO_BASED)
			return 0;
925
		BUG_ON(t->type == DM_TYPE_DAX_BIO_BASED);
926 927 928
		goto verify_rq_based;
	}

K
Kiyoshi Ueda 已提交
929 930
	for (i = 0; i < t->num_targets; i++) {
		tgt = t->targets + i;
931 932 933
		if (dm_target_hybrid(tgt))
			hybrid = 1;
		else if (dm_target_request_based(tgt))
K
Kiyoshi Ueda 已提交
934 935 936 937 938 939 940 941 942 943 944
			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;
		}
	}

945 946 947 948 949 950
	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.
		 */
951
		if (__table_type_request_based(live_md_type))
952 953 954 955 956
			request_based = 1;
		else
			bio_based = 1;
	}

K
Kiyoshi Ueda 已提交
957 958 959
	if (bio_based) {
		/* We must use this table as bio-based */
		t->type = DM_TYPE_BIO_BASED;
M
Mike Snitzer 已提交
960 961
		if (dm_table_supports_dax(t) ||
		    (list_empty(devices) && live_md_type == DM_TYPE_DAX_BIO_BASED))
962
			t->type = DM_TYPE_DAX_BIO_BASED;
K
Kiyoshi Ueda 已提交
963 964 965 966 967
		return 0;
	}

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

968 969 970 971 972 973 974
	/*
	 * 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:
975 976 977 978 979 980 981 982 983 984 985
	/*
	 * 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;
	}

986 987 988 989 990 991 992 993 994 995 996 997 998
	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;
	}

K
Kiyoshi Ueda 已提交
999 1000
	/* Non-request-stackable devices can't be used for request-based dm */
	list_for_each_entry(dd, devices, list) {
1001 1002
		struct request_queue *q = bdev_get_queue(dd->dm_dev->bdev);

1003
		if (!queue_is_rq_based(q)) {
1004 1005
			DMERR("table load rejected: including"
			      " non-request-stackable devices");
K
Kiyoshi Ueda 已提交
1006 1007
			return -EINVAL;
		}
1008 1009

		if (q->mq_ops)
1010 1011 1012
			mq_count++;
		else
			sq_count++;
1013
	}
1014 1015 1016
	if (sq_count && mq_count) {
		DMERR("table load rejected: not all devices are blk-mq request-stackable");
		return -EINVAL;
1017
	}
1018
	t->all_blk_mq = mq_count > 0;
K
Kiyoshi Ueda 已提交
1019

1020 1021 1022 1023 1024
	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;
	}

K
Kiyoshi Ueda 已提交
1025 1026 1027
	return 0;
}

1028
enum dm_queue_mode dm_table_get_type(struct dm_table *t)
K
Kiyoshi Ueda 已提交
1029 1030 1031 1032
{
	return t->type;
}

1033 1034 1035 1036 1037
struct target_type *dm_table_get_immutable_target_type(struct dm_table *t)
{
	return t->immutable_target_type;
}

M
Mike Snitzer 已提交
1038 1039 1040 1041 1042 1043 1044 1045 1046 1047
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;
}

1048 1049
struct dm_target *dm_table_get_wildcard_target(struct dm_table *t)
{
1050 1051
	struct dm_target *ti;
	unsigned i;
1052

1053 1054
	for (i = 0; i < dm_table_get_num_targets(t); i++) {
		ti = dm_table_get_target(t, i);
1055 1056 1057 1058 1059 1060 1061
		if (dm_target_is_wildcard(ti->type))
			return ti;
	}

	return NULL;
}

1062 1063 1064 1065 1066
bool dm_table_bio_based(struct dm_table *t)
{
	return __table_type_bio_based(dm_table_get_type(t));
}

K
Kiyoshi Ueda 已提交
1067 1068
bool dm_table_request_based(struct dm_table *t)
{
1069
	return __table_type_request_based(dm_table_get_type(t));
1070 1071
}

1072
bool dm_table_all_blk_mq_devices(struct dm_table *t)
1073
{
1074
	return t->all_blk_mq;
K
Kiyoshi Ueda 已提交
1075 1076
}

1077
static int dm_table_alloc_md_mempools(struct dm_table *t, struct mapped_device *md)
K
Kiyoshi Ueda 已提交
1078
{
1079
	enum dm_queue_mode type = dm_table_get_type(t);
1080
	unsigned per_io_data_size = 0;
1081
	struct dm_target *tgt;
M
Mikulas Patocka 已提交
1082
	unsigned i;
K
Kiyoshi Ueda 已提交
1083

1084
	if (unlikely(type == DM_TYPE_NONE)) {
K
Kiyoshi Ueda 已提交
1085 1086 1087 1088
		DMWARN("no table type is set, can't allocate mempools");
		return -EINVAL;
	}

1089
	if (__table_type_bio_based(type))
1090 1091
		for (i = 0; i < t->num_targets; i++) {
			tgt = t->targets + i;
1092
			per_io_data_size = max(per_io_data_size, tgt->per_io_data_size);
1093 1094
		}

1095
	t->mempools = dm_alloc_md_mempools(md, type, t->integrity_supported, per_io_data_size);
1096 1097
	if (!t->mempools)
		return -ENOMEM;
K
Kiyoshi Ueda 已提交
1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112

	return 0;
}

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

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

L
Linus Torvalds 已提交
1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129
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 */
J
Jun'ichi Nomura 已提交
1130
	for (i = t->depth - 2; i >= 0; i--) {
L
Linus Torvalds 已提交
1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141
		t->index[i] = indexes;
		indexes += (KEYS_PER_NODE * t->counts[i]);
		setup_btree_index(i, t);
	}

	return 0;
}

/*
 * Builds the btree to index the map.
 */
1142
static int dm_table_build_index(struct dm_table *t)
L
Linus Torvalds 已提交
1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160
{
	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;
}

1161 1162 1163 1164 1165
static bool integrity_profile_exists(struct gendisk *disk)
{
	return !!blk_get_integrity(disk);
}

1166 1167 1168 1169
/*
 * Get a disk whose integrity profile reflects the table's profile.
 * Returns NULL if integrity support was inconsistent or unavailable.
 */
1170
static struct gendisk * dm_table_get_integrity_disk(struct dm_table *t)
1171 1172 1173 1174
{
	struct list_head *devices = dm_table_get_devices(t);
	struct dm_dev_internal *dd = NULL;
	struct gendisk *prev_disk = NULL, *template_disk = NULL;
1175 1176 1177 1178 1179 1180 1181
	unsigned i;

	for (i = 0; i < dm_table_get_num_targets(t); i++) {
		struct dm_target *ti = dm_table_get_target(t, i);
		if (!dm_target_passes_integrity(ti->type))
			goto no_integrity;
	}
1182 1183

	list_for_each_entry(dd, devices, list) {
1184
		template_disk = dd->dm_dev->bdev->bd_disk;
1185
		if (!integrity_profile_exists(template_disk))
1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203
			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;
}

1204
/*
1205 1206 1207
 * 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
1208
 * during table load because this table may use other DM device(s) which
1209 1210 1211 1212
 * 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.
1213
 */
1214
static int dm_table_register_integrity(struct dm_table *t)
1215
{
1216
	struct mapped_device *md = t->md;
1217
	struct gendisk *template_disk = NULL;
1218

1219 1220 1221 1222
	/* If target handles integrity itself do not register it here. */
	if (t->integrity_added)
		return 0;

1223
	template_disk = dm_table_get_integrity_disk(t);
1224 1225
	if (!template_disk)
		return 0;
1226

1227
	if (!integrity_profile_exists(dm_disk(md))) {
1228
		t->integrity_supported = true;
1229 1230 1231 1232 1233 1234 1235
		/*
		 * 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;
1236 1237 1238
	}

	/*
1239
	 * If DM device already has an initialized integrity
1240 1241
	 * profile the new profile should not conflict.
	 */
1242
	if (blk_integrity_compare(dm_disk(md), template_disk) < 0) {
1243 1244 1245 1246 1247 1248 1249
		DMWARN("%s: conflict with existing integrity profile: "
		       "%s profile mismatch",
		       dm_device_name(t->md),
		       template_disk->disk_name);
		return 1;
	}

1250
	/* Preserve existing integrity profile */
1251
	t->integrity_supported = true;
1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262
	return 0;
}

/*
 * 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;

1263
	r = dm_table_determine_type(t);
1264
	if (r) {
1265
		DMERR("unable to determine table type");
1266 1267 1268 1269 1270 1271 1272 1273 1274
		return r;
	}

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

1275
	r = dm_table_register_integrity(t);
1276 1277 1278 1279 1280
	if (r) {
		DMERR("could not register integrity profile.");
		return r;
	}

1281
	r = dm_table_alloc_md_mempools(t, t->md);
1282 1283 1284 1285 1286 1287
	if (r)
		DMERR("unable to allocate mempools");

	return r;
}

A
Arjan van de Ven 已提交
1288
static DEFINE_MUTEX(_event_lock);
L
Linus Torvalds 已提交
1289 1290 1291
void dm_table_event_callback(struct dm_table *t,
			     void (*fn)(void *), void *context)
{
A
Arjan van de Ven 已提交
1292
	mutex_lock(&_event_lock);
L
Linus Torvalds 已提交
1293 1294
	t->event_fn = fn;
	t->event_context = context;
A
Arjan van de Ven 已提交
1295
	mutex_unlock(&_event_lock);
L
Linus Torvalds 已提交
1296 1297 1298 1299 1300 1301 1302 1303 1304 1305
}

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());

A
Arjan van de Ven 已提交
1306
	mutex_lock(&_event_lock);
L
Linus Torvalds 已提交
1307 1308
	if (t->event_fn)
		t->event_fn(t->event_context);
A
Arjan van de Ven 已提交
1309
	mutex_unlock(&_event_lock);
L
Linus Torvalds 已提交
1310
}
1311
EXPORT_SYMBOL(dm_table_event);
L
Linus Torvalds 已提交
1312 1313 1314 1315 1316

sector_t dm_table_get_size(struct dm_table *t)
{
	return t->num_targets ? (t->highs[t->num_targets - 1] + 1) : 0;
}
1317
EXPORT_SYMBOL(dm_table_get_size);
L
Linus Torvalds 已提交
1318 1319 1320

struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index)
{
1321
	if (index >= t->num_targets)
L
Linus Torvalds 已提交
1322 1323 1324 1325 1326 1327 1328
		return NULL;

	return t->targets + index;
}

/*
 * Search the btree for the correct target.
1329 1330 1331
 *
 * Caller should check returned pointer with dm_target_is_valid()
 * to trap I/O beyond end of device.
L
Linus Torvalds 已提交
1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349
 */
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];
}

1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367
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;
}

/*
 * 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)
{
1368 1369
	struct dm_target *ti;
	unsigned i, num_devices;
1370

1371 1372
	for (i = 0; i < dm_table_get_num_targets(table); i++) {
		ti = dm_table_get_target(table, i);
1373 1374 1375 1376

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

1377
		num_devices = 0;
1378 1379 1380 1381 1382 1383 1384 1385
		ti->type->iterate_devices(ti, count_device, &num_devices);
		if (num_devices)
			return false;
	}

	return true;
}

1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467
static int device_is_zoned_model(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);
	enum blk_zoned_model *zoned_model = data;

	return q && blk_queue_zoned_model(q) == *zoned_model;
}

static bool dm_table_supports_zoned_model(struct dm_table *t,
					  enum blk_zoned_model zoned_model)
{
	struct dm_target *ti;
	unsigned i;

	for (i = 0; i < dm_table_get_num_targets(t); i++) {
		ti = dm_table_get_target(t, i);

		if (zoned_model == BLK_ZONED_HM &&
		    !dm_target_supports_zoned_hm(ti->type))
			return false;

		if (!ti->type->iterate_devices ||
		    !ti->type->iterate_devices(ti, device_is_zoned_model, &zoned_model))
			return false;
	}

	return true;
}

static int device_matches_zone_sectors(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);
	unsigned int *zone_sectors = data;

	return q && blk_queue_zone_sectors(q) == *zone_sectors;
}

static bool dm_table_matches_zone_sectors(struct dm_table *t,
					  unsigned int zone_sectors)
{
	struct dm_target *ti;
	unsigned i;

	for (i = 0; i < dm_table_get_num_targets(t); i++) {
		ti = dm_table_get_target(t, i);

		if (!ti->type->iterate_devices ||
		    !ti->type->iterate_devices(ti, device_matches_zone_sectors, &zone_sectors))
			return false;
	}

	return true;
}

static int validate_hardware_zoned_model(struct dm_table *table,
					 enum blk_zoned_model zoned_model,
					 unsigned int zone_sectors)
{
	if (zoned_model == BLK_ZONED_NONE)
		return 0;

	if (!dm_table_supports_zoned_model(table, zoned_model)) {
		DMERR("%s: zoned model is not consistent across all devices",
		      dm_device_name(table->md));
		return -EINVAL;
	}

	/* Check zone size validity and compatibility */
	if (!zone_sectors || !is_power_of_2(zone_sectors))
		return -EINVAL;

	if (!dm_table_matches_zone_sectors(table, zone_sectors)) {
		DMERR("%s: zone sectors is not consistent across all devices",
		      dm_device_name(table->md));
		return -EINVAL;
	}

	return 0;
}

1468 1469 1470 1471 1472 1473
/*
 * Establish the new table's queue_limits and validate them.
 */
int dm_calculate_queue_limits(struct dm_table *table,
			      struct queue_limits *limits)
{
1474
	struct dm_target *ti;
1475
	struct queue_limits ti_limits;
1476
	unsigned i;
1477 1478
	enum blk_zoned_model zoned_model = BLK_ZONED_NONE;
	unsigned int zone_sectors = 0;
1479

1480
	blk_set_stacking_limits(limits);
1481

1482
	for (i = 0; i < dm_table_get_num_targets(table); i++) {
1483
		blk_set_stacking_limits(&ti_limits);
1484

1485
		ti = dm_table_get_target(table, i);
1486 1487 1488 1489 1490 1491 1492 1493 1494 1495

		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);

1496 1497 1498 1499 1500 1501 1502 1503 1504
		if (zoned_model == BLK_ZONED_NONE && ti_limits.zoned != BLK_ZONED_NONE) {
			/*
			 * After stacking all limits, validate all devices
			 * in table support this zoned model and zone sectors.
			 */
			zoned_model = ti_limits.zoned;
			zone_sectors = ti_limits.chunk_sectors;
		}

1505 1506 1507 1508
		/* Set I/O hints portion of queue limits */
		if (ti->type->io_hints)
			ti->type->io_hints(ti, &ti_limits);

1509 1510 1511 1512
		/*
		 * Check each device area is consistent with the target's
		 * overall queue limits.
		 */
1513 1514
		if (ti->type->iterate_devices(ti, device_area_is_invalid,
					      &ti_limits))
1515 1516 1517 1518 1519 1520 1521 1522
			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)
1523
			DMWARN("%s: adding target device "
1524
			       "(start sect %llu len %llu) "
1525
			       "caused an alignment inconsistency",
1526 1527 1528
			       dm_device_name(table->md),
			       (unsigned long long) ti->begin,
			       (unsigned long long) ti->len);
1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544

		/*
		 * FIXME: this should likely be moved to blk_stack_limits(), would
		 * also eliminate limits->zoned stacking hack in dm_set_device_limits()
		 */
		if (limits->zoned == BLK_ZONED_NONE && ti_limits.zoned != BLK_ZONED_NONE) {
			/*
			 * By default, the stacked limits zoned model is set to
			 * BLK_ZONED_NONE in blk_set_stacking_limits(). Update
			 * this model using the first target model reported
			 * that is not BLK_ZONED_NONE. This will be either the
			 * first target device zoned model or the model reported
			 * by the target .io_hints.
			 */
			limits->zoned = ti_limits.zoned;
		}
1545 1546
	}

1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564
	/*
	 * Verify that the zoned model and zone sectors, as determined before
	 * any .io_hints override, are the same across all devices in the table.
	 * - this is especially relevant if .io_hints is emulating a disk-managed
	 *   zoned model (aka BLK_ZONED_NONE) on host-managed zoned block devices.
	 * BUT...
	 */
	if (limits->zoned != BLK_ZONED_NONE) {
		/*
		 * ...IF the above limits stacking determined a zoned model
		 * validate that all of the table's devices conform to it.
		 */
		zoned_model = limits->zoned;
		zone_sectors = limits->chunk_sectors;
	}
	if (validate_hardware_zoned_model(table, zoned_model, zone_sectors))
		return -EINVAL;

1565 1566 1567
	return validate_hardware_logical_block_alignment(table, limits);
}

M
Martin K. Petersen 已提交
1568
/*
1569 1570 1571
 * 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.
M
Martin K. Petersen 已提交
1572
 */
1573
static void dm_table_verify_integrity(struct dm_table *t)
M
Martin K. Petersen 已提交
1574
{
1575
	struct gendisk *template_disk = NULL;
M
Martin K. Petersen 已提交
1576

1577 1578 1579
	if (t->integrity_added)
		return;

1580 1581 1582 1583 1584 1585 1586 1587 1588 1589
	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;
	}
M
Martin K. Petersen 已提交
1590

1591
	if (integrity_profile_exists(dm_disk(t->md))) {
1592 1593
		DMWARN("%s: unable to establish an integrity profile",
		       dm_device_name(t->md));
1594 1595
		blk_integrity_unregister(dm_disk(t->md));
	}
M
Martin K. Petersen 已提交
1596 1597
}

1598 1599 1600
static int device_flush_capable(struct dm_target *ti, struct dm_dev *dev,
				sector_t start, sector_t len, void *data)
{
J
Jens Axboe 已提交
1601
	unsigned long flush = (unsigned long) data;
1602 1603
	struct request_queue *q = bdev_get_queue(dev->bdev);

J
Jens Axboe 已提交
1604
	return q && (q->queue_flags & flush);
1605 1606
}

J
Jens Axboe 已提交
1607
static bool dm_table_supports_flush(struct dm_table *t, unsigned long flush)
1608 1609
{
	struct dm_target *ti;
1610
	unsigned i;
1611 1612 1613 1614 1615 1616 1617

	/*
	 * 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.
	 */
1618 1619
	for (i = 0; i < dm_table_get_num_targets(t); i++) {
		ti = dm_table_get_target(t, i);
1620

1621
		if (!ti->num_flush_bios)
1622 1623
			continue;

1624
		if (ti->flush_supported)
1625
			return true;
1626

1627
		if (ti->type->iterate_devices &&
J
Jens Axboe 已提交
1628
		    ti->type->iterate_devices(ti, device_flush_capable, (void *) flush))
1629
			return true;
1630 1631
	}

1632
	return false;
1633 1634
}

1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665
static int device_dax_write_cache_enabled(struct dm_target *ti,
					  struct dm_dev *dev, sector_t start,
					  sector_t len, void *data)
{
	struct dax_device *dax_dev = dev->dax_dev;

	if (!dax_dev)
		return false;

	if (dax_write_cache_enabled(dax_dev))
		return true;
	return false;
}

static int dm_table_supports_dax_write_cache(struct dm_table *t)
{
	struct dm_target *ti;
	unsigned i;

	for (i = 0; i < dm_table_get_num_targets(t); i++) {
		ti = dm_table_get_target(t, i);

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

	return false;
}

1666 1667 1668 1669 1670 1671 1672 1673
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);
}

1674 1675 1676 1677 1678 1679 1680 1681
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);
}

1682 1683 1684 1685 1686 1687 1688 1689
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);
}

1690 1691
static bool dm_table_all_devices_attribute(struct dm_table *t,
					   iterate_devices_callout_fn func)
1692 1693
{
	struct dm_target *ti;
1694
	unsigned i;
1695

1696 1697
	for (i = 0; i < dm_table_get_num_targets(t); i++) {
		ti = dm_table_get_target(t, i);
1698 1699

		if (!ti->type->iterate_devices ||
1700
		    !ti->type->iterate_devices(ti, func, NULL))
1701
			return false;
1702 1703
	}

1704
	return true;
1705 1706
}

M
Mike Snitzer 已提交
1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717
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;
}

static bool dm_table_supports_write_same(struct dm_table *t)
{
	struct dm_target *ti;
1718
	unsigned i;
M
Mike Snitzer 已提交
1719

1720 1721
	for (i = 0; i < dm_table_get_num_targets(t); i++) {
		ti = dm_table_get_target(t, i);
M
Mike Snitzer 已提交
1722

1723
		if (!ti->num_write_same_bios)
M
Mike Snitzer 已提交
1724 1725 1726
			return false;

		if (!ti->type->iterate_devices ||
M
Mike Snitzer 已提交
1727
		    ti->type->iterate_devices(ti, device_not_write_same_capable, NULL))
M
Mike Snitzer 已提交
1728 1729 1730 1731 1732 1733
			return false;
	}

	return true;
}

1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761
static int device_not_write_zeroes_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_zeroes_sectors;
}

static bool dm_table_supports_write_zeroes(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_zeroes_bios)
			return false;

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

	return true;
}


1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772
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);
}

static bool dm_table_supports_discards(struct dm_table *t)
{
	struct dm_target *ti;
1773
	unsigned i;
1774 1775 1776 1777 1778 1779 1780 1781

	/*
	 * 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.
	 */
1782 1783
	for (i = 0; i < dm_table_get_num_targets(t); i++) {
		ti = dm_table_get_target(t, i);
1784 1785 1786 1787 1788

		if (!ti->num_discard_bios)
			continue;

		if (ti->discards_supported)
1789
			return true;
1790 1791 1792

		if (ti->type->iterate_devices &&
		    ti->type->iterate_devices(ti, device_discard_capable, NULL))
1793
			return true;
1794 1795
	}

1796
	return false;
1797 1798
}

1799 1800
void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
			       struct queue_limits *limits)
L
Linus Torvalds 已提交
1801
{
1802
	bool wc = false, fua = false;
1803

L
Linus Torvalds 已提交
1804
	/*
1805
	 * Copy table's limits to the DM device's request_queue
L
Linus Torvalds 已提交
1806
	 */
1807
	q->limits = *limits;
1808

M
Mike Snitzer 已提交
1809 1810 1811 1812 1813
	if (!dm_table_supports_discards(t))
		queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, q);
	else
		queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);

J
Jens Axboe 已提交
1814
	if (dm_table_supports_flush(t, (1UL << QUEUE_FLAG_WC))) {
1815
		wc = true;
J
Jens Axboe 已提交
1816
		if (dm_table_supports_flush(t, (1UL << QUEUE_FLAG_FUA)))
1817
			fua = true;
1818
	}
1819
	blk_queue_write_cache(q, wc, fua);
1820

1821 1822 1823
	if (dm_table_supports_dax_write_cache(t))
		dax_write_cache(t->md->dax_dev, true);

1824 1825
	/* Ensure that all underlying devices are non-rotational. */
	if (dm_table_all_devices_attribute(t, device_is_nonrot))
1826 1827 1828 1829
		queue_flag_set_unlocked(QUEUE_FLAG_NONROT, q);
	else
		queue_flag_clear_unlocked(QUEUE_FLAG_NONROT, q);

M
Mike Snitzer 已提交
1830 1831
	if (!dm_table_supports_write_same(t))
		q->limits.max_write_same_sectors = 0;
1832 1833
	if (!dm_table_supports_write_zeroes(t))
		q->limits.max_write_zeroes_sectors = 0;
M
Mike Snitzer 已提交
1834

1835 1836 1837 1838 1839
	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);

1840
	dm_table_verify_integrity(t);
K
Kiyoshi Ueda 已提交
1841

1842 1843 1844 1845 1846 1847 1848 1849
	/*
	 * 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);
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}

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

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

1862
fmode_t dm_table_get_mode(struct dm_table *t)
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{
	return t->mode;
}
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EXPORT_SYMBOL(dm_table_get_mode);
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enum suspend_mode {
	PRESUSPEND,
	PRESUSPEND_UNDO,
	POSTSUSPEND,
};

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

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	lockdep_assert_held(&t->md->suspend_lock);

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	while (i--) {
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		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:
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			if (ti->type->postsuspend)
				ti->type->postsuspend(ti);
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			break;
		}
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		ti++;
	}
}

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

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	suspend_targets(t, PRESUSPEND);
}

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

	suspend_targets(t, PRESUSPEND_UNDO);
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}

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

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	suspend_targets(t, POSTSUSPEND);
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}

1924
int dm_table_resume_targets(struct dm_table *t)
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{
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	int i, r = 0;

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	lockdep_assert_held(&t->md->suspend_lock);

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	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);
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		if (r) {
			DMERR("%s: %s: preresume failed, error = %d",
			      dm_device_name(t->md), ti->type->name, r);
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			return r;
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		}
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	}
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	for (i = 0; i < t->num_targets; i++) {
		struct dm_target *ti = t->targets + i;

		if (ti->type->resume)
			ti->type->resume(ti);
	}
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	return 0;
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}

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void dm_table_add_target_callbacks(struct dm_table *t, struct dm_target_callbacks *cb)
{
	list_add(&cb->list, &t->target_callbacks);
}
EXPORT_SYMBOL_GPL(dm_table_add_target_callbacks);

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

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

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

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

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	return r;
}

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struct mapped_device *dm_table_get_md(struct dm_table *t)
{
	return t->md;
}
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EXPORT_SYMBOL(dm_table_get_md);
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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) {
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		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);
		}
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	}
}
EXPORT_SYMBOL(dm_table_run_md_queue_async);