Release 4.7 drivers/md/dm.c

/*
 * Copyright (C) 2001, 2002 Sistina Software (UK) Limited.
 * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
 *
 * This file is released under the GPL.
 */

#include "dm.h"
#include "dm-uevent.h"

#include <linux/init.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/moduleparam.h>
#include <linux/blkpg.h>
#include <linux/bio.h>
#include <linux/mempool.h>
#include <linux/slab.h>
#include <linux/idr.h>
#include <linux/hdreg.h>
#include <linux/delay.h>
#include <linux/wait.h>
#include <linux/kthread.h>
#include <linux/ktime.h>
#include <linux/elevator.h> /* for rq_end_sector() */
#include <linux/blk-mq.h>
#include <linux/pr.h>

#include <trace/events/block.h>


#define DM_MSG_PREFIX "core"

#ifdef CONFIG_PRINTK
/*
 * ratelimit state to be used in DMXXX_LIMIT().
 */
DEFINE_RATELIMIT_STATE(dm_ratelimit_state,
		       DEFAULT_RATELIMIT_INTERVAL,
		       DEFAULT_RATELIMIT_BURST);

EXPORT_SYMBOL(dm_ratelimit_state);
#endif

/*
 * Cookies are numeric values sent with CHANGE and REMOVE
 * uevents while resuming, removing or renaming the device.
 */

#define DM_COOKIE_ENV_VAR_NAME "DM_COOKIE"

#define DM_COOKIE_LENGTH 24


static const char *_name = DM_NAME;


static unsigned int major = 0;

static unsigned int _major = 0;

static DEFINE_IDR(_minor_idr);

static DEFINE_SPINLOCK(_minor_lock);

static void do_deferred_remove(struct work_struct *w);

static DECLARE_WORK(deferred_remove_work, do_deferred_remove);


static struct workqueue_struct *deferred_remove_workqueue;

/*
 * For bio-based dm.
 * One of these is allocated per bio.
 */

struct dm_io {
	
struct mapped_device *md;
	
int error;
	
atomic_t io_count;
	
struct bio *bio;
	
unsigned long start_time;
	
spinlock_t endio_lock;
	
struct dm_stats_aux stats_aux;
};

/*
 * For request-based dm.
 * One of these is allocated per request.
 */

struct dm_rq_target_io {
	
struct mapped_device *md;
	
struct dm_target *ti;
	

struct request *orig, *clone;
	
struct kthread_work work;
	
int error;
	
union map_info info;
	
struct dm_stats_aux stats_aux;
	
unsigned long duration_jiffies;
	
unsigned n_sectors;
};

/*
 * For request-based dm - the bio clones we allocate are embedded in these
 * structs.
 *
 * We allocate these with bio_alloc_bioset, using the front_pad parameter when
 * the bioset is created - this means the bio has to come at the end of the
 * struct.
 */

struct dm_rq_clone_bio_info {
	
struct bio *orig;
	
struct dm_rq_target_io *tio;
	
struct bio clone;
};


#define MINOR_ALLOCED ((void *)-1)

/*
 * Bits for the md->flags field.
 */

#define DMF_BLOCK_IO_FOR_SUSPEND 0

#define DMF_SUSPENDED 1

#define DMF_FROZEN 2

#define DMF_FREEING 3

#define DMF_DELETING 4

#define DMF_NOFLUSH_SUSPENDING 5

#define DMF_DEFERRED_REMOVE 6

#define DMF_SUSPENDED_INTERNALLY 7

/*
 * Work processed by per-device workqueue.
 */

struct mapped_device {
	
struct srcu_struct io_barrier;
	
struct mutex suspend_lock;

	/*
         * The current mapping (struct dm_table *).
         * Use dm_get_live_table{_fast} or take suspend_lock for
         * dereference.
         */
	
void __rcu *map;

	
struct list_head table_devices;
	
struct mutex table_devices_lock;

	
unsigned long flags;

	
struct request_queue *queue;
	
int numa_node_id;

	
unsigned type;
	/* Protect queue and type against concurrent access. */
	
struct mutex type_lock;

	
atomic_t holders;
	
atomic_t open_count;

	
struct dm_target *immutable_target;
	
struct target_type *immutable_target_type;

	
struct gendisk *disk;
	
char name[16];

	
void *interface_ptr;

	/*
         * A list of ios that arrived while we were suspended.
         */
	
atomic_t pending[2];
	
wait_queue_head_t wait;
	
struct work_struct work;
	
spinlock_t deferred_lock;
	
struct bio_list deferred;

	/*
         * Event handling.
         */
	
wait_queue_head_t eventq;
	
atomic_t event_nr;
	
atomic_t uevent_seq;
	
struct list_head uevent_list;
	
spinlock_t uevent_lock; /* Protect access to uevent_list */

	/* the number of internal suspends */
	
unsigned internal_suspend_count;

	/*
         * Processing queue (flush)
         */
	
struct workqueue_struct *wq;

	/*
         * io objects are allocated from here.
         */
	
mempool_t *io_pool;
	
mempool_t *rq_pool;

	
struct bio_set *bs;

	/*
         * freeze/thaw support require holding onto a super block
         */
	
struct super_block *frozen_sb;

	/* forced geometry settings */
	
struct hd_geometry geometry;

	
struct block_device *bdev;

	/* kobject and completion */
	
struct dm_kobject_holder kobj_holder;

	/* zero-length flush that will be cloned and submitted to targets */
	
struct bio flush_bio;

	
struct dm_stats stats;

	
struct kthread_worker kworker;
	
struct task_struct *kworker_task;

	/* for request-based merge heuristic in dm_request_fn() */
	
unsigned seq_rq_merge_deadline_usecs;
	
int last_rq_rw;
	
sector_t last_rq_pos;
	
ktime_t last_rq_start_time;

	/* for blk-mq request-based DM support */
	
struct blk_mq_tag_set *tag_set;
	
bool use_blk_mq:1;
	
bool init_tio_pdu:1;
};

#ifdef CONFIG_DM_MQ_DEFAULT

static bool use_blk_mq = true;
#else

static bool use_blk_mq = false;
#endif


#define DM_MQ_NR_HW_QUEUES 1

#define DM_MQ_QUEUE_DEPTH 2048

#define DM_NUMA_NODE NUMA_NO_NODE


static unsigned dm_mq_nr_hw_queues = DM_MQ_NR_HW_QUEUES;

static unsigned dm_mq_queue_depth = DM_MQ_QUEUE_DEPTH;

static int dm_numa_node = DM_NUMA_NODE;



bool dm_use_blk_mq(struct mapped_device *md)
{
	return md->use_blk_mq;
}
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EXPORT_SYMBOL_GPL(dm_use_blk_mq);

/*
 * For mempools pre-allocation at the table loading time.
 */

struct dm_md_mempools {
	
mempool_t *io_pool;
	
mempool_t *rq_pool;
	
struct bio_set *bs;
};


struct table_device {
	
struct list_head list;
	
atomic_t count;
	
struct dm_dev dm_dev;
};


#define RESERVED_BIO_BASED_IOS		16

#define RESERVED_REQUEST_BASED_IOS	256

#define RESERVED_MAX_IOS		1024

static struct kmem_cache *_io_cache;

static struct kmem_cache *_rq_tio_cache;

static struct kmem_cache *_rq_cache;

/*
 * Bio-based DM's mempools' reserved IOs set by the user.
 */

static unsigned reserved_bio_based_ios = RESERVED_BIO_BASED_IOS;

/*
 * Request-based DM's mempools' reserved IOs set by the user.
 */

static unsigned reserved_rq_based_ios = RESERVED_REQUEST_BASED_IOS;



static int __dm_get_module_param_int(int *module_param, int min, int max)
{
	int param = ACCESS_ONCE(*module_param);
	int modified_param = 0;
	bool modified = true;

	if (param < min)
		modified_param = min;
	else if (param > max)
		modified_param = max;
	else
		modified = false;

	if (modified) {
		(void)cmpxchg(module_param, param, modified_param);
		param = modified_param;
	}

	return param;
}

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static unsigned __dm_get_module_param(unsigned *module_param,
				      unsigned def, unsigned max)
{
	unsigned param = ACCESS_ONCE(*module_param);
	unsigned modified_param = 0;

	if (!param)
		modified_param = def;
	else if (param > max)
		modified_param = max;

	if (modified_param) {
		(void)cmpxchg(module_param, param, modified_param);
		param = modified_param;
	}

	return param;
}

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unsigned dm_get_reserved_bio_based_ios(void)
{
	return __dm_get_module_param(&reserved_bio_based_ios,
				     RESERVED_BIO_BASED_IOS, RESERVED_MAX_IOS);
}
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EXPORT_SYMBOL_GPL(dm_get_reserved_bio_based_ios);



unsigned dm_get_reserved_rq_based_ios(void)
{
	return __dm_get_module_param(&reserved_rq_based_ios,
				     RESERVED_REQUEST_BASED_IOS, RESERVED_MAX_IOS);
}
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EXPORT_SYMBOL_GPL(dm_get_reserved_rq_based_ios);



static unsigned dm_get_blk_mq_nr_hw_queues(void)
{
	return __dm_get_module_param(&dm_mq_nr_hw_queues, 1, 32);
}

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static unsigned dm_get_blk_mq_queue_depth(void)
{
	return __dm_get_module_param(&dm_mq_queue_depth,
				     DM_MQ_QUEUE_DEPTH, BLK_MQ_MAX_DEPTH);
}

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static unsigned dm_get_numa_node(void)
{
	return __dm_get_module_param_int(&dm_numa_node,
					 DM_NUMA_NODE, num_online_nodes() - 1);
}

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static int __init local_init(void)
{
	int r = -ENOMEM;

	/* allocate a slab for the dm_ios */
	_io_cache = KMEM_CACHE(dm_io, 0);
	if (!_io_cache)
		return r;

	_rq_tio_cache = KMEM_CACHE(dm_rq_target_io, 0);
	if (!_rq_tio_cache)
		goto out_free_io_cache;

	_rq_cache = kmem_cache_create("dm_old_clone_request", sizeof(struct request),
				      __alignof__(struct request), 0, NULL);
	if (!_rq_cache)
		goto out_free_rq_tio_cache;

	r = dm_uevent_init();
	if (r)
		goto out_free_rq_cache;

	deferred_remove_workqueue = alloc_workqueue("kdmremove", WQ_UNBOUND, 1);
	if (!deferred_remove_workqueue) {
		r = -ENOMEM;
		goto out_uevent_exit;
	}

	_major = major;
	r = register_blkdev(_major, _name);
	if (r < 0)
		goto out_free_workqueue;

	if (!_major)
		_major = r;

	return 0;

out_free_workqueue:
	destroy_workqueue(deferred_remove_workqueue);
out_uevent_exit:
	dm_uevent_exit();
out_free_rq_cache:
	kmem_cache_destroy(_rq_cache);
out_free_rq_tio_cache:
	kmem_cache_destroy(_rq_tio_cache);
out_free_io_cache:
	kmem_cache_destroy(_io_cache);

	return r;
}

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mike snitzer
mike snitzer
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mikulas patocka
mikulas patocka
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2
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mike anderson
mike anderson
9
4.76%
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andrew morton
andrew morton
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alasdair kergon
alasdair kergon
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static void local_exit(void)
{
	flush_scheduled_work();
	destroy_workqueue(deferred_remove_workqueue);

	kmem_cache_destroy(_rq_cache);
	kmem_cache_destroy(_rq_tio_cache);
	kmem_cache_destroy(_io_cache);
	unregister_blkdev(_major, _name);
	dm_uevent_exit();

	_major = 0;

	DMINFO("cleaned up");
}

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static int (*_inits[])(void) __initdata = {
	local_init,
	dm_target_init,
	dm_linear_init,
	dm_stripe_init,
	dm_io_init,
	dm_kcopyd_init,
	dm_interface_init,
	dm_statistics_init,
};


static void (*_exits[])(void) = {
	local_exit,
	dm_target_exit,
	dm_linear_exit,
	dm_stripe_exit,
	dm_io_exit,
	dm_kcopyd_exit,
	dm_interface_exit,
	dm_statistics_exit,

};


static int __init dm_init(void)
{
	const int count = ARRAY_SIZE(_inits);

	int r, i;

	for (i = 0; i < count; i++) {
		r = _inits[i]();
		if (r)
			goto bad;
	}

	return 0;

      bad:
	while (i--)
		_exits[i]();

	return r;
}

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static void __exit dm_exit(void)
{
	int i = ARRAY_SIZE(_exits);

	while (i--)
		_exits[i]();

	/*
         * Should be empty by this point.
         */
	idr_destroy(&_minor_idr);
}

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andries brouwer
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/*
 * Block device functions
 */


int dm_deleting_md(struct mapped_device *md)
{
	return test_bit(DMF_DELETING, &md->flags);
}

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static int dm_blk_open(struct block_device *bdev, fmode_t mode)
{
	struct mapped_device *md;

	spin_lock(&_minor_lock);

	md = bdev->bd_disk->private_data;
	if (!md)
		goto out;

	if (test_bit(DMF_FREEING, &md->flags) ||
	    dm_deleting_md(md)) {
		md = NULL;
		goto out;
	}

	dm_get(md);
	atomic_inc(&md->open_count);
out:
	spin_unlock(&_minor_lock);

	return md ? 0 : -ENXIO;
}

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mike anderson
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static void dm_blk_close(struct gendisk *disk, fmode_t mode)
{
	struct mapped_device *md;

	spin_lock(&_minor_lock);

	md = disk->private_data;
	if (WARN_ON(!md))
		goto out;

	if (atomic_dec_and_test(&md->open_count) &&
	    (test_bit(DMF_DEFERRED_REMOVE, &md->flags)))
		queue_work(deferred_remove_workqueue, &deferred_remove_work);

	dm_put(md);
out:
	spin_unlock(&_minor_lock);
}

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alan cox
alan cox
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arnd bergmann
arnd bergmann
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alasdair kergon
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al viro
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milan broz
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int dm_open_count(struct mapped_device *md)
{
	return atomic_read(&md->open_count);
}

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/*
 * Guarantees nothing is using the device before it's deleted.
 */


int dm_lock_for_deletion(struct mapped_device *md, bool mark_deferred, bool only_deferred)
{
	int r = 0;

	spin_lock(&_minor_lock);

	if (dm_open_count(md)) {
		r = -EBUSY;
		if (mark_deferred)
			set_bit(DMF_DEFERRED_REMOVE, &md->flags);
	} else if (only_deferred && !test_bit(DMF_DEFERRED_REMOVE, &md->flags))
		r = -EEXIST;
	else
		set_bit(DMF_DELETING, &md->flags);

	spin_unlock(&_minor_lock);

	return r;
}

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int dm_cancel_deferred_remove(struct mapped_device *md)
{
	int r = 0;

	spin_lock(&_minor_lock);

	if (test_bit(DMF_DELETING, &md->flags))
		r = -EBUSY;
	else
		clear_bit(DMF_DEFERRED_REMOVE, &md->flags);

	spin_unlock(&_minor_lock);

	return r;
}

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static void do_deferred_remove(struct work_struct *w)
{
	dm_deferred_remove();
}

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sector_t dm_get_size(struct mapped_device *md)
{
	return get_capacity(md->disk);
}

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struct request_queue *dm_get_md_queue(struct mapped_device *md)
{
	return md->queue;
}

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struct dm_stats *dm_get_stats(struct mapped_device *md)
{
	return &md->stats;
}

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static int dm_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
{
	struct mapped_device *md = bdev->bd_disk->private_data;

	return dm_get_geometry(md, geo);
}

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static int dm_grab_bdev_for_ioctl(struct mapped_device *md,
				  struct block_device **bdev,
				  fmode_t *mode)
{
	struct dm_target *tgt;
	struct dm_table *map;
	int srcu_idx, r;

retry:
	r = -ENOTTY;
	map = dm_get_live_table(md, &srcu_idx);
	if (!map || !dm_table_get_size(map))
		goto out;

	/* We only support devices that have a single target */
	if (dm_table_get_num_targets(map) != 1)
		goto out;

	tgt = dm_table_get_target(map, 0);
	if (!tgt->type->prepare_ioctl)
		goto out;

	if (dm_suspended_md(md)) {
		r = -EAGAIN;
		goto out;
	}

	r = tgt->type->prepare_ioctl(tgt, bdev, mode);
	if (r < 0)
		goto out;

	bdgrab(*bdev);
	dm_put_live_table(md, srcu_idx);
	return r;

out:
	dm_put_live_table(md, srcu_idx);
	if (r == -ENOTCONN && !fatal_signal_pending(current)) {
		msleep(10);
		goto retry;
	}
	return r;
}

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hannes reinecke
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1
10.00%
al viro
al viro
4
2.07%
1
10.00%
kiyoshi ueda
kiyoshi ueda
1
0.52%
1
10.00%
Total
193
100.00%
10
100.00%



static int dm_blk_ioctl(struct block_device *bdev, fmode_t mode,
			unsigned int cmd, unsigned long arg)
{
	struct mapped_device *md = bdev->bd_disk->private_data;
	int r;

	r = dm_grab_bdev_for_ioctl(md, &bdev, &mode);
	if (r < 0)
		return r;

	if (r > 0) {
		/*
                 * Target determined this ioctl is being issued against
                 * a logical partition of the parent bdev; so extra
                 * validation is needed.
                 */
		r = scsi_verify_blk_ioctl(NULL, cmd);
		if (r)
			goto out;
	}

	r =  __blkdev_driver_ioctl(bdev, mode, cmd, arg);
out:
	bdput(bdev);
	return r;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
christoph hellwig
christoph hellwig
101
95.28%
1
33.33%
mike snitzer
mike snitzer
5
4.72%
2
66.67%
Total
106
100.00%
3
100.00%



static struct dm_io *alloc_io(struct mapped_device *md)
{
	return mempool_alloc(md->io_pool, GFP_NOIO);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
alan cox
alan cox
16
69.57%
1
50.00%
joe thornber
joe thornber
7
30.43%
1
50.00%
Total
23
100.00%
2
100.00%



static void free_io(struct mapped_device *md, struct dm_io *io)
{
	mempool_free(io, md->io_pool);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
alan cox
alan cox
17
68.00%
1
50.00%
joe thornber
joe thornber
8
32.00%
1
50.00%
Total
25
100.00%
2
100.00%



static void free_tio(struct dm_target_io *tio)
{
	bio_put(&tio->clone);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
andrew morton
andrew morton
15
78.95%
1
33.33%
mikulas patocka
mikulas patocka
3
15.79%
1
33.33%
alasdair kergon
alasdair kergon
1
5.26%
1
33.33%
Total
19
100.00%
3
100.00%



static struct dm_rq_target_io *alloc_old_rq_tio(struct mapped_device *md,
						gfp_t gfp_mask)
{
	return mempool_alloc(md->io_pool, gfp_mask);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
kiyoshi ueda
kiyoshi ueda
24
92.31%
2
50.00%
mike snitzer
mike snitzer
1
3.85%
1
25.00%
jun'ichi nomura
jun'ichi nomura
1
3.85%
1
25.00%
Total
26
100.00%
4
100.00%



static void free_old_rq_tio(struct dm_rq_target_io *tio)
{
	mempool_free(tio, tio->md->io_pool);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
kiyoshi ueda
kiyoshi ueda
20
90.91%
1
33.33%
mike snitzer
mike snitzer
1
4.55%
1
33.33%
jun'ichi nomura
jun'ichi nomura
1
4.55%
1
33.33%
Total
22
100.00%
3
100.00%



static struct request *alloc_old_clone_request(struct mapped_device *md,
					       gfp_t gfp_mask)
{
	return mempool_alloc(md->rq_pool, gfp_mask);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
26
100.00%
2
100.00%
Total
26
100.00%
2
100.00%



static void free_old_clone_request(struct mapped_device *md, struct request *rq)
{
	mempool_free(rq, md->rq_pool);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
25
100.00%
2
100.00%
Total
25
100.00%
2
100.00%



static int md_in_flight(struct mapped_device *md)
{
	return atomic_read(&md->pending[READ]) +
	       atomic_read(&md->pending[WRITE]);
}

Contributors
Person
Tokens
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CommitProp
kiyoshi ueda
kiyoshi ueda
34
100.00%
1
100.00%
Total
34
100.00%
1
100.00%



static void start_io_acct(struct dm_io *io)
{
	struct mapped_device *md = io->md;
	struct bio *bio = io->bio;
	int cpu;
	int rw = bio_data_dir(bio);

	io->start_time = jiffies;

	cpu = part_stat_lock();
	part_round_stats(cpu, &dm_disk(md)->part0);
	part_stat_unlock();
	atomic_set(&dm_disk(md)->part0.in_flight[rw],
		atomic_inc_return(&md->pending[rw]));

	if (unlikely(dm_stats_used(&md->stats)))
		dm_stats_account_io(&md->stats, bio->bi_rw, bio->bi_iter.bi_sector,
				    bio_sectors(bio), false, 0, &io->stats_aux);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mikulas patocka
mikulas patocka
52
37.41%
1
14.29%
jun'ichi nomura
jun'ichi nomura
51
36.69%
1
14.29%
tejun heo
tejun heo
15
10.79%
2
28.57%
nikanth karthikesan
nikanth karthikesan
14
10.07%
1
14.29%
li shaohua
li shaohua
5
3.60%
1
14.29%
kent overstreet
kent overstreet
2
1.44%
1
14.29%
Total
139
100.00%
7
100.00%



static void end_io_acct(struct dm_io *io)
{
	struct mapped_device *md = io->md;
	struct bio *bio = io->bio;
	unsigned long duration = jiffies - io->start_time;
	int pending;
	int rw = bio_data_dir(bio);

	generic_end_io_acct(rw, &dm_disk(md)->part0, io->start_time);

	if (unlikely(dm_stats_used(&md->stats)))
		dm_stats_account_io(&md->stats, bio->bi_rw, bio->bi_iter.bi_sector,
				    bio_sectors(bio), true, duration, &io->stats_aux);

	/*
         * After this is decremented the bio must not be touched if it is
         * a flush.
         */
	pending = atomic_dec_return(&md->pending[rw]);
	atomic_set(&dm_disk(md)->part0.in_flight[rw], pending);
	pending += atomic_read(&md->pending[rw^0x1]);

	/* nudge anyone waiting on suspend queue */
	if (!pending)
		wake_up(&md->wait);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
jun'ichi nomura
jun'ichi nomura
63
36.42%
1
10.00%
mikulas patocka
mikulas patocka
56
32.37%
2
20.00%
nikanth karthikesan
nikanth karthikesan
21
12.14%
1
10.00%
li shaohua
li shaohua
16
9.25%
1
10.00%
tejun heo
tejun heo
11
6.36%
3
30.00%
gu zheng
gu zheng
4
2.31%
1
10.00%
kent overstreet
kent overstreet
2
1.16%
1
10.00%
Total
173
100.00%
10
100.00%

/*
 * Add the bio to the list of deferred io.
 */


static void queue_io(struct mapped_device *md, struct bio *bio)
{
	unsigned long flags;

	spin_lock_irqsave(&md->deferred_lock, flags);
	bio_list_add(&md->deferred, bio);
	spin_unlock_irqrestore(&md->deferred_lock, flags);
	queue_work(md->wq, &md->work);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
benjamin marzinski
benjamin marzinski
38
61.29%
1
25.00%
alan cox
alan cox
18
29.03%
1
25.00%
kiyoshi ueda
kiyoshi ueda
5
8.06%
1
25.00%
mikulas patocka
mikulas patocka
1
1.61%
1
25.00%
Total
62
100.00%
4
100.00%

/*
 * Everyone (including functions in this file), should use this
 * function to access the md->map field, and make sure they call
 * dm_put_live_table() when finished.
 */

struct dm_table *dm_get_live_table(struct mapped_device *md, int *srcu_idx) __acquires(md->io_barrier)
{
	*srcu_idx = srcu_read_lock(&md->io_barrier);

	return srcu_dereference(md->map, &md->io_barrier);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
benjamin marzinski
benjamin marzinski
46
100.00%
1
100.00%
Total
46
100.00%
1
100.00%


void dm_put_live_table(struct mapped_device *md, int srcu_idx) __releases(md->io_barrier)
{
	srcu_read_unlock(&md->io_barrier, srcu_idx);
}

Contributors
Person
Tokens
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CommitProp
benjamin marzinski
benjamin marzinski
29
100.00%
1
100.00%
Total
29
100.00%
1
100.00%



void dm_sync_table(struct mapped_device *md)
{
	synchronize_srcu(&md->io_barrier);
	synchronize_rcu_expedited();
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
benjamin marzinski
benjamin marzinski
21
100.00%
1
100.00%
Total
21
100.00%
1
100.00%

/*
 * A fast alternative to dm_get_live_table/dm_put_live_table.
 * The caller must not block between these two functions.
 */


static struct dm_table *dm_get_live_table_fast(struct mapped_device *md) __acquires(RCU)
{
	rcu_read_lock();
	return rcu_dereference(md->map);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
benjamin marzinski
benjamin marzinski
28
100.00%
1
100.00%
Total
28
100.00%
1
100.00%



static void dm_put_live_table_fast(struct mapped_device *md) __releases(RCU)
{
	rcu_read_unlock();
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
benjamin marzinski
benjamin marzinski
18
100.00%
1
100.00%
Total
18
100.00%
1
100.00%

/*
 * Open a table device so we can use it as a map destination.
 */


static int open_table_device(struct table_device *td, dev_t dev,
			     struct mapped_device *md)
{
	static char *_claim_ptr = "I belong to device-mapper";
	struct block_device *bdev;

	int r;

	BUG_ON(td->dm_dev.bdev);

	bdev = blkdev_get_by_dev(dev, td->dm_dev.mode | FMODE_EXCL, _claim_ptr);
	if (IS_ERR(bdev))
		return PTR_ERR(bdev);

	r = bd_link_disk_holder(bdev, dm_disk(md));
	if (r) {
		blkdev_put(bdev, td->dm_dev.mode | FMODE_EXCL);
		return r;
	}

	td->dm_dev.bdev = bdev;
	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
benjamin marzinski
benjamin marzinski
118
100.00%
1
100.00%
Total
118
100.00%
1
100.00%

/*
 * Close a table device that we've been using.
 */


static void close_table_device(struct table_device *td, struct mapped_device *md)
{
	if (!td->dm_dev.bdev)
		return;

	bd_unlink_disk_holder(td->dm_dev.bdev, dm_disk(md));
	blkdev_put(td->dm_dev.bdev, td->dm_dev.mode | FMODE_EXCL);
	td->dm_dev.bdev = NULL;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
benjamin marzinski
benjamin marzinski
65
100.00%
1
100.00%
Total
65
100.00%
1
100.00%



static struct table_device *find_table_device(struct list_head *l, dev_t dev,
					      fmode_t mode) {
	struct table_device *td;

	list_for_each_entry(td, l, list)
		if (td->dm_dev.bdev->bd_dev == dev && td->dm_dev.mode == mode)
			return td;

	return NULL;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
benjamin marzinski
benjamin marzinski
58
100.00%
1
100.00%
Total
58
100.00%
1
100.00%



int dm_get_table_device(struct mapped_device *md, dev_t dev, fmode_t mode,
			struct dm_dev **result) {
	int r;
	struct table_device *td;

	mutex_lock(&md->table_devices_lock);
	td = find_table_device(&md->table_devices, dev, mode);
	if (!td) {
		td = kmalloc_node(sizeof(*td), GFP_KERNEL, md->numa_node_id);
		if (!td) {
			mutex_unlock(&md->table_devices_lock);
			return -ENOMEM;
		}

		td->dm_dev.mode = mode;
		td->dm_dev.bdev = NULL;

		if ((r = open_table_device(td, dev, md))) {
			mutex_unlock(&md->table_devices_lock);
			kfree(td);
			return r;
		}

		format_dev_t(td->dm_dev.name, dev);

		atomic_set(&td->count, 0);
		list_add(&td->list, &md->table_devices);
	}
	atomic_inc(&td->count);
	mutex_unlock(&md->table_devices_lock);

	*result = &td->dm_dev;
	return 0;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
benjamin marzinski
benjamin marzinski
166
80.98%
1
12.50%
mikulas patocka
mikulas patocka
22
10.73%
3
37.50%
andrew morton
andrew morton
6
2.93%
2
25.00%
alan cox
alan cox
6
2.93%
1
12.50%
mike snitzer
mike snitzer
5
2.44%
1
12.50%
Total
205
100.00%
8
100.00%


EXPORT_SYMBOL_GPL(dm_get_table_device);



void dm_put_table_device(struct mapped_device *md, struct dm_dev *d)
{
	struct table_device *td = container_of(d, struct table_device, dm_dev);

	mutex_lock(&md->table_devices_lock);
	if (atomic_dec_and_test(&td->count)) {
		close_table_device(td, md);
		list_del(&td->list);
		kfree(td);
	}
	mutex_unlock(&md->table_devices_lock);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
benjamin marzinski
benjamin marzinski
50
64.10%
1
33.33%
mikulas patocka
mikulas patocka
18
23.08%
1
33.33%
andrew morton
andrew morton
10
12.82%
1
33.33%
Total
78
100.00%
3
100.00%


EXPORT_SYMBOL(dm_put_table_device);



static void free_table_devices(struct list_head *devices)
{
	struct list_head *tmp, *next;

	list_for_each_safe(tmp, next, devices) {
		struct table_device *td = list_entry(tmp, struct table_device, list);

		DMWARN("dm_destroy: %s still exists with %d references",
		       td->dm_dev.name, atomic_read(&td->count));
		kfree(td);
	}
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
benjamin marzinski
benjamin marzinski
59
86.76%
1
50.00%
mikulas patocka
mikulas patocka
9
13.24%
1
50.00%
Total
68
100.00%
2
100.00%

/*
 * Get the geometry associated with a dm device
 */


int dm_get_geometry(struct mapped_device *md, struct hd_geometry *geo)
{
	*geo = md->geometry;

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
darrick j. wong
darrick j. wong
25
100.00%
1
100.00%
Total
25
100.00%
1
100.00%

/*
 * Set the geometry of a device.
 */


int dm_set_geometry(struct mapped_device *md, struct hd_geometry *geo)
{
	sector_t sz = (sector_t)geo->cylinders * geo->heads * geo->sectors;

	if (geo->start > sz) {
		DMWARN("Start sector is beyond the geometry limits.");
		return -EINVAL;
	}

	md->geometry = *geo;

	return 0;
}

Contributors
Person
Tokens
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CommitProp
darrick j. wong
darrick j. wong
62
100.00%
1
100.00%
Total
62
100.00%
1
100.00%

/*-----------------------------------------------------------------
 * CRUD START:
 *   A more elegant soln is in the works that uses the queue
 *   merge fn, unfortunately there are a couple of changes to
 *   the block layer that I want to make for this.  So in the
 *   interests of getting something for people to use I give
 *   you this clearly demarcated crap.
 *---------------------------------------------------------------*/



static int __noflush_suspending(struct mapped_device *md)
{
	return test_bit(DMF_NOFLUSH_SUSPENDING, &md->flags);
}

Contributors
Person
Tokens
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CommitProp
kiyoshi ueda
kiyoshi ueda
22
100.00%
1
100.00%
Total
22
100.00%
1
100.00%

/*
 * Decrements the number of outstanding ios that a bio has been
 * cloned into, completing the original io if necc.
 */


static void dec_pending(struct dm_io *io, int error)
{
	unsigned long flags;
	int io_error;
	struct bio *bio;
	struct mapped_device *md = io->md;

	/* Push-back supersedes any I/O errors */
	if (unlikely(error)) {
		spin_lock_irqsave(&io->endio_lock, flags);
		if (!(io->error > 0 && __noflush_suspending(md)))
			io->error = error;
		spin_unlock_irqrestore(&io->endio_lock, flags);
	}

	if (atomic_dec_and_test(&io->io_count)) {
		if (io->error == DM_ENDIO_REQUEUE) {
			/*
                         * Target requested pushing back the I/O.
                         */
			spin_lock_irqsave(&md->deferred_lock, flags);
			if (__noflush_suspending(md))
				bio_list_add_head(&md->deferred, io->bio);
			else
				/* noflush suspend was interrupted. */
				io->error = -EIO;
			spin_unlock_irqrestore(&md->deferred_lock, flags);
		}

		io_error = io->error;
		bio = io->bio;
		end_io_acct(io);
		free_io(md, io);

		if (io_error == DM_ENDIO_REQUEUE)
			return;

		if ((bio->bi_rw & REQ_FLUSH) && bio->bi_iter.bi_size) {
			/*
                         * Preflush done for flush with data, reissue
                         * without REQ_FLUSH.
                         */
			bio->bi_rw &= ~REQ_FLUSH;
			queue_io(md, bio);
		} else {
			/* done with normal IO or empty flush */
			trace_block_bio_complete(md->queue, bio, io_error);
			bio->bi_error = io_error;
			bio_endio(bio);
		}
	}
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
kiyoshi ueda
kiyoshi ueda
105
42.34%
2
15.38%
alan cox
alan cox
38
15.32%
1
7.69%
milan broz
milan broz
30
12.10%
1
7.69%
mikulas patocka
mikulas patocka
24
9.68%
3
23.08%
tejun heo
tejun heo
15
6.05%
1
7.69%
mike snitzer
mike snitzer
13
5.24%
1
7.69%
linus torvalds
linus torvalds
11
4.44%
1
7.69%
christoph hellwig
christoph hellwig
6
2.42%
1
7.69%
joe thornber
joe thornber
4
1.61%
1
7.69%
kent overstreet
kent overstreet
2
0.81%
1
7.69%
Total
248
100.00%
13
100.00%



static void disable_write_same(struct mapped_device *md)
{
	struct queue_limits *limits = dm_get_queue_limits(md);

	/* device doesn't really support WRITE SAME, disable it */
	limits->max_write_same_sectors = 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
28
100.00%
1
100.00%
Total
28
100.00%
1
100.00%



static void clone_endio(struct bio *bio)
{
	int error = bio->bi_error;
	int r = error;
	struct dm_target_io *tio = container_of(bio, struct dm_target_io, clone);
	struct dm_io *io = tio->io;
	struct mapped_device *md = tio->io->md;
	dm_endio_fn endio = tio->ti->type->end_io;

	if (endio) {
		r = endio(tio->ti, bio, error);
		if (r < 0 || r == DM_ENDIO_REQUEUE)
			/*
                         * error and requeue request are handled
                         * in dec_pending().
                         */
			error = r;
		else if (r == DM_ENDIO_INCOMPLETE)
			/* The target will handle the io */
			return;
		else if (r) {
			DMWARN("unimplemented target endio return value: %d", r);
			BUG();
		}
	}

	if (unlikely(r == -EREMOTEIO && (bio->bi_rw & REQ_WRITE_SAME) &&
		     !bdev_get_queue(bio->bi_bdev)->limits.max_write_same_sectors))
		disable_write_same(md);

	free_tio(tio);
	dec_pending(io, error);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
andrew morton
andrew morton
55
31.25%
1
8.33%
mike snitzer
mike snitzer
35
19.89%
1
8.33%
kiyoshi ueda
kiyoshi ueda
25
14.20%
2
16.67%
alan cox
alan cox
17
9.66%
1
8.33%
milan broz
milan broz
17
9.66%
1
8.33%
stefan bader
stefan bader
8
4.55%
1
8.33%
mikulas patocka
mikulas patocka
8
4.55%
1
8.33%
christoph hellwig
christoph hellwig
7
3.98%
1
8.33%
neil brown
neil brown
2
1.14%
1
8.33%
alasdair kergon
alasdair kergon
1
0.57%
1
8.33%
alex chen
alex chen
1
0.57%
1
8.33%
Total
176
100.00%
12
100.00%

/*
 * Partial completion handling for request-based dm
 */


static void end_clone_bio(struct bio *clone)
{
	struct dm_rq_clone_bio_info *info =
		container_of(clone, struct dm_rq_clone_bio_info, clone);
	struct dm_rq_target_io *tio = info->tio;
	struct bio *bio = info->orig;
	unsigned int nr_bytes = info->orig->bi_iter.bi_size;
	int error = clone->bi_error;

	bio_put(clone);

	if (tio->error)
		/*
                 * An error has already been detected on the request.
                 * Once error occurred, just let clone->end_io() handle
                 * the remainder.
                 */
		return;
	else if (error) {
		/*
                 * Don't notice the error to the upper layer yet.
                 * The error handling decision is made by the target driver,
                 * when the request is completed.
                 */
		tio->error = error;
		return;
	}

	/*
         * I/O for the bio successfully completed.
         * Notice the data completion to the upper layer.
         */

	/*
         * bios are processed from the head of the list.
         * So the completing bio should always be rq->bio.
         * If it's not, something wrong is happening.
         */
	if (tio->orig->bio != bio)
		DMERR("bio completion is going in the middle of the request");

	/*
         * Update the original request.
         * Do not use blk_end_request() here, because it may complete
         * the original request before the clone, and break the ordering.
         */
	blk_update_request(tio->orig, 0, nr_bytes);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
111
92.50%
1
50.00%
jun'ichi nomura
jun'ichi nomura
9
7.50%
1
50.00%
Total
120
100.00%
2
100.00%



static struct dm_rq_target_io *tio_from_request(struct request *rq)
{
	return (rq->q->mq_ops ? blk_mq_rq_to_pdu(rq) : rq->special);
}

Contributors
Person
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mike snitzer
mike snitzer
31
100.00%
1
100.00%
Total
31
100.00%
1
100.00%



static void rq_end_stats(struct mapped_device *md, struct request *orig)
{
	if (unlikely(dm_stats_used(&md->stats))) {
		struct dm_rq_target_io *tio = tio_from_request(orig);
		tio->duration_jiffies = jiffies - tio->duration_jiffies;
		dm_stats_account_io(&md->stats, orig->cmd_flags, blk_rq_pos(orig),
				    tio->n_sectors, true, tio->duration_jiffies,
				    &tio->stats_aux);
	}
}

Contributors
Person
Tokens
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CommitProp
mikulas patocka
mikulas patocka
83
100.00%
1
100.00%
Total
83
100.00%
1
100.00%

/*
 * Don't touch any member of the md after calling this function because
 * the md may be freed in dm_put() at the end of this function.
 * Or do dm_get() before calling this function and dm_put() later.
 */


static void rq_completed(struct mapped_device *md, int rw, bool run_queue)
{
	atomic_dec(&md->pending[rw]);

	/* nudge anyone waiting on suspend queue */
	if (!md_in_flight(md))
		wake_up(&md->wait);

	/*
         * Run this off this callpath, as drivers could invoke end_io while
         * inside their request_fn (and holding the queue lock). Calling
         * back into ->request_fn() could deadlock attempting to grab the
         * queue lock again.
         */
	if (!md->queue->mq_ops && run_queue)
		blk_run_queue_async(md->queue);

	/*
         * dm_put() must be at the end of this function. See the comment above
         */
	dm_put(md);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
kiyoshi ueda
kiyoshi ueda
29
41.43%
2
18.18%
alan cox
alan cox
15
21.43%
1
9.09%
mike snitzer
mike snitzer
12
17.14%
3
27.27%
jens axboe
jens axboe
6
8.57%
2
18.18%
joe thornber
joe thornber
5
7.14%
1
9.09%
andrew morton
andrew morton
2
2.86%
1
9.09%
keith busch
keith busch
1
1.43%
1
9.09%
Total
70
100.00%
11
100.00%



static void free_rq_clone(struct request *clone)
{
	struct dm_rq_target_io *tio = clone->end_io_data;
	struct mapped_device *md = tio->md;

	blk_rq_unprep_clone(clone);

	if (md->type == DM_TYPE_MQ_REQUEST_BASED)
		/* stacked on blk-mq queue(s) */
		tio->ti->type->release_clone_rq(clone);
	else if (!md->queue->mq_ops)
		/* request_fn queue stacked on request_fn queue(s) */
		free_old_clone_request(md, clone);

	if (!md->queue->mq_ops)
		free_old_rq_tio(tio);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
62
72.09%
7
87.50%
kiyoshi ueda
kiyoshi ueda
24
27.91%
1
12.50%
Total
86
100.00%
8
100.00%

/*
 * Complete the clone and the original request.
 * Must be called without clone's queue lock held,
 * see end_clone_request() for more details.
 */


static void dm_end_request(struct request *clone, int error)
{
	int rw = rq_data_dir(clone);
	struct dm_rq_target_io *tio = clone->end_io_data;
	struct mapped_device *md = tio->md;
	struct request *rq = tio->orig;

	if (rq->cmd_type == REQ_TYPE_BLOCK_PC) {
		rq->errors = clone->errors;
		rq->resid_len = clone->resid_len;

		if (rq->sense)
			/*
                         * We are using the sense buffer of the original
                         * request.
                         * So setting the length of the sense data is enough.
                         */
			rq->sense_len = clone->sense_len;
	}

	free_rq_clone(clone);
	rq_end_stats(md, rq);
	if (!rq->q->mq_ops)
		blk_end_request_all(rq, error);
	else
		blk_mq_end_request(rq, error);
	rq_completed(md, rw, true);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
kiyoshi ueda
kiyoshi ueda
106
78.52%
1
20.00%
mike snitzer
mike snitzer
17
12.59%
1
20.00%
mikulas patocka
mikulas patocka
7
5.19%
1
20.00%
christoph hellwig
christoph hellwig
4
2.96%
1
20.00%
tejun heo
tejun heo
1
0.74%
1
20.00%
Total
135
100.00%
5
100.00%



static void dm_unprep_request(struct request *rq)
{
	struct dm_rq_target_io *tio = tio_from_request(rq);
	struct request *clone = tio->clone;

	if (!rq->q->mq_ops) {
		rq->special = NULL;
		rq->cmd_flags &= ~REQ_DONTPREP;
	}

	if (clone)
		free_rq_clone(clone);
	else if (!tio->md->queue->mq_ops)
		free_old_rq_tio(tio);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
35
43.75%
4
36.36%
kiyoshi ueda
kiyoshi ueda
25
31.25%
2
18.18%
keith busch
keith busch
11
13.75%
1
9.09%
andrew morton
andrew morton
5
6.25%
2
18.18%
stefan bader
stefan bader
3
3.75%
1
9.09%
alan cox
alan cox
1
1.25%
1
9.09%
Total
80
100.00%
11
100.00%

/*
 * Requeue the original request of a clone.
 */


static void dm_old_requeue_request(struct request *rq)
{
	struct request_queue *q = rq->q;
	unsigned long flags;

	spin_lock_irqsave(q->queue_lock, flags);
	blk_requeue_request(q, rq);
	blk_run_queue_async(q);
	spin_unlock_irqrestore(q->queue_lock, flags);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
kiyoshi ueda
kiyoshi ueda
39
72.22%
1
14.29%
alan cox
alan cox
6
11.11%
1
14.29%
jun'ichi nomura
jun'ichi nomura
5
9.26%
1
14.29%
mike snitzer
mike snitzer
3
5.56%
3
42.86%
keith busch
keith busch
1
1.85%
1
14.29%
Total
54
100.00%
7
100.00%



static void dm_mq_requeue_request(struct request *rq)
{
	struct request_queue *q = rq->q;
	unsigned long flags;

	blk_mq_requeue_request(rq);
	spin_lock_irqsave(q->queue_lock, flags);
	if (!blk_queue_stopped(q))
		blk_mq_kick_requeue_list(q);
	spin_unlock_irqrestore(q->queue_lock, flags);
}

Contributors
Person
Tokens
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CommitProp
mike snitzer
mike snitzer
60
100.00%
1
100.00%
Total
60
100.00%
1
100.00%



static void dm_requeue_original_request(struct mapped_device *md,
					struct request *rq)
{
	int rw = rq_data_dir(rq);

	rq_end_stats(md, rq);
	dm_unprep_request(rq);

	if (!rq->q->mq_ops)
		dm_old_requeue_request(rq);
	else
		dm_mq_requeue_request(rq);

	rq_completed(md, rw, false);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
47
72.31%
4
40.00%
kiyoshi ueda
kiyoshi ueda
8
12.31%
2
20.00%
mikulas patocka
mikulas patocka
4
6.15%
1
10.00%
bryn m. reeves
bryn m. reeves
4
6.15%
1
10.00%
alan cox
alan cox
1
1.54%
1
10.00%
keith busch
keith busch
1
1.54%
1
10.00%
Total
65
100.00%
10
100.00%



static void dm_old_stop_queue(struct request_queue *q)
{
	unsigned long flags;

	spin_lock_irqsave(q->queue_lock, flags);
	if (blk_queue_stopped(q)) {
		spin_unlock_irqrestore(q->queue_lock, flags);
		return;
	}

	blk_stop_queue(q);
	spin_unlock_irqrestore(q->queue_lock, flags);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
kiyoshi ueda
kiyoshi ueda
27
47.37%
1
16.67%
mike snitzer
mike snitzer
22
38.60%
3
50.00%
peter osterlund
peter osterlund
5
8.77%
1
16.67%
stefan bader
stefan bader
3
5.26%
1
16.67%
Total
57
100.00%
6
100.00%



static void dm_stop_queue(struct request_queue *q)
{
	if (!q->mq_ops)
		dm_old_stop_queue(q);
	else
		blk_mq_stop_hw_queues(q);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
kiyoshi ueda
kiyoshi ueda
16
55.17%
1
20.00%
mike snitzer
mike snitzer
10
34.48%
2
40.00%
joe thornber
joe thornber
2
6.90%
1
20.00%
alan cox
alan cox
1
3.45%
1
20.00%
Total
29
100.00%
5
100.00%



static void dm_old_start_queue(struct request_queue *q)
{
	unsigned long flags;

	spin_lock_irqsave(q->queue_lock, flags);
	if (blk_queue_stopped(q))
		blk_start_queue(q);
	spin_unlock_irqrestore(q->queue_lock, flags);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
kiyoshi ueda
kiyoshi ueda
32
71.11%
1
25.00%
mike snitzer
mike snitzer
9
20.00%
2
50.00%
alan cox
alan cox
4
8.89%
1
25.00%
Total
45
100.00%
4
100.00%



static void dm_start_queue(struct request_queue *q)
{
	if (!q->mq_ops)
		dm_old_start_queue(q);
	else {
		blk_mq_start_stopped_hw_queues(q, true);
		blk_mq_kick_requeue_list(q);
	}
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
31
81.58%
3
75.00%
kiyoshi ueda
kiyoshi ueda
7
18.42%
1
25.00%
Total
38
100.00%
4
100.00%



static void dm_done(struct request *clone, int error, bool mapped)
{
	int r = error;
	struct dm_rq_target_io *tio = clone->end_io_data;
	dm_request_endio_fn rq_end_io = NULL;

	if (tio->ti) {
		rq_end_io = tio->ti->type->rq_end_io;

		if (mapped && rq_end_io)
			r = rq_end_io(tio->ti, clone, error, &tio->info);
	}

	if (unlikely(r == -EREMOTEIO && (clone->cmd_flags & REQ_WRITE_SAME) &&
		     !clone->q->limits.max_write_same_sectors))
		disable_write_same(tio->md);

	if (r <= 0)
		/* The target wants to complete the I/O */
		dm_end_request(clone, r);
	else if (r == DM_ENDIO_INCOMPLETE)
		/* The target will handle the I/O */
		return;
	else if (r == DM_ENDIO_REQUEUE)
		/* The target wants to requeue the I/O */
		dm_requeue_original_request(tio->md, tio->orig);
	else {
		DMWARN("unimplemented target endio return value: %d", r);
		BUG();
	}
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
80
47.90%
4
40.00%
kiyoshi ueda
kiyoshi ueda
63
37.72%
2
20.00%
martin k. petersen
martin k. petersen
19
11.38%
2
20.00%
joe thornber
joe thornber
5
2.99%
2
20.00%
Total
167
100.00%
10
100.00%

/*
 * Request completion handler for request-based dm
 */


static void dm_softirq_done(struct request *rq)
{
	bool mapped = true;
	struct dm_rq_target_io *tio = tio_from_request(rq);
	struct request *clone = tio->clone;
	int rw;

	if (!clone) {
		rq_end_stats(tio->md, rq);
		rw = rq_data_dir(rq);
		if (!rq->q->mq_ops) {
			blk_end_request_all(rq, tio->error);
			rq_completed(tio->md, rw, false);
			free_old_rq_tio(tio);
		} else {
			blk_mq_end_request(rq, tio->error);
			rq_completed(tio->md, rw, false);
		}
		return;
	}

	if (rq->cmd_flags & REQ_FAILED)
		mapped = false;

	dm_done(clone, tio->error, mapped);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
80
55.56%
3
50.00%
kiyoshi ueda
kiyoshi ueda
49
34.03%
1
16.67%
mikulas patocka
mikulas patocka
9
6.25%
1
16.67%
keith busch
keith busch
6
4.17%
1
16.67%
Total
144
100.00%
6
100.00%

/*
 * Complete the clone and the original request with the error status
 * through softirq context.
 */


static void dm_complete_request(struct request *rq, int error)
{
	struct dm_rq_target_io *tio = tio_from_request(rq);

	tio->error = error;
	if (!rq->q->mq_ops)
		blk_complete_request(rq);
	else
		blk_mq_complete_request(rq, error);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
20
38.46%
2
25.00%
kiyoshi ueda
kiyoshi ueda
15
28.85%
1
12.50%
joe thornber
joe thornber
13
25.00%
2
25.00%
alan cox
alan cox
2
3.85%
1
12.50%
keith busch
keith busch
1
1.92%
1
12.50%
stefan bader
stefan bader
1
1.92%
1
12.50%
Total
52
100.00%
8
100.00%

/*
 * Complete the not-mapped clone and the original request with the error status
 * through softirq context.
 * Target's rq_end_io() function isn't called.
 * This may be used when the target's map_rq() or clone_and_map_rq() functions fail.
 */


static void dm_kill_unmapped_request(struct request *rq, int error)
{
	rq->cmd_flags |= REQ_FAILED;
	dm_complete_request(rq, error);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
kiyoshi ueda
kiyoshi ueda
17
62.96%
1
25.00%
martin k. petersen
martin k. petersen
7
25.93%
1
25.00%
keith busch
keith busch
2
7.41%
1
25.00%
mike snitzer
mike snitzer
1
3.70%
1
25.00%
Total
27
100.00%
4
100.00%

/*
 * Called with the clone's queue lock held (in the case of .request_fn)
 */


static void end_clone_request(struct request *clone, int error)
{
	struct dm_rq_target_io *tio = clone->end_io_data;

	if (!clone->q->mq_ops) {
		/*
                 * For just cleaning up the information of the queue in which
                 * the clone was dispatched.
                 * The clone is *NOT* freed actually here because it is alloced
                 * from dm own mempool (REQ_ALLOCED isn't set).
                 */
		__blk_put_request(clone->q, clone);
	}

	/*
         * Actual request completion is done in a softirq context which doesn't
         * hold the clone's queue lock.  Otherwise, deadlock could occur because:
         *     - another request may be submitted by the upper level driver
         *       of the stacking during the completion
         *     - the submission which requires queue lock may be done
         *       against this clone's queue
         */
	dm_complete_request(tio->orig, error);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mikulas patocka
mikulas patocka
14
25.93%
1
20.00%
keith busch
keith busch
13
24.07%
1
20.00%
kiyoshi ueda
kiyoshi ueda
12
22.22%
1
20.00%
mike snitzer
mike snitzer
12
22.22%
1
20.00%
alasdair kergon
alasdair kergon
3
5.56%
1
20.00%
Total
54
100.00%
5
100.00%

/*
 * Return maximum size of I/O possible at the supplied sector up to the current
 * target boundary.
 */


static sector_t max_io_len_target_boundary(sector_t sector, struct dm_target *ti)
{
	sector_t target_offset = dm_target_offset(ti, sector);

	return ti->len - target_offset;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
14
45.16%
1
33.33%
alasdair kergon
alasdair kergon
11
35.48%
1
33.33%
kiyoshi ueda
kiyoshi ueda
6
19.35%
1
33.33%
Total
31
100.00%
3
100.00%



static sector_t max_io_len(sector_t sector, struct dm_target *ti)
{
	sector_t len = max_io_len_target_boundary(sector, ti);
	sector_t offset, max_len;

	/*
         * Does the target need to split even further?
         */
	if (ti->max_io_len) {
		offset = dm_target_offset(ti, sector);
		if (unlikely(ti->max_io_len & (ti->max_io_len - 1)))
			max_len = sector_div(offset, ti->max_io_len);
		else
			max_len = offset & (ti->max_io_len - 1);
		max_len = ti->max_io_len - max_len;

		if (len > max_len)
			len = max_len;
	}

	return len;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
72
66.06%
2
40.00%
kiyoshi ueda
kiyoshi ueda
22
20.18%
1
20.00%
mikulas patocka
mikulas patocka
14
12.84%
1
20.00%
alasdair kergon
alasdair kergon
1
0.92%
1
20.00%
Total
109
100.00%
5
100.00%



int dm_set_target_max_io_len(struct dm_target *ti, sector_t len)
{
	if (len > UINT_MAX) {
		DMERR("Specified maximum size of target IO (%llu) exceeds limit (%u)",
		      (unsigned long long)len, UINT_MAX);
		ti->error = "Maximum size of target IO is too large";
		return -EINVAL;
	}

	ti->max_io_len = (uint32_t) len;

	return 0;
}
Contributors
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Tokens
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CommitProp
mike snitzer
mike snitzer
57
100.00%
1
100.00%
Total
57
100.00%
1
100.00%


EXPORT_SYMBOL_GPL(dm_set_target_max_io_len);

/*
 * A target may call dm_accept_partial_bio only from the map routine.  It is
 * allowed for all bio types except REQ_FLUSH.
 *
 * dm_accept_partial_bio informs the dm that the target only wants to process
 * additional n_sectors sectors of the bio and the rest of the data should be
 * sent in a next bio.
 *
 * A diagram that explains the arithmetics:
 * +--------------------+---------------+-------+
 * |         1          |       2       |   3   |
 * +--------------------+---------------+-------+
 *
 * <-------------- *tio->len_ptr --------------->
 *                      <------- bi_size ------->
 *                      <-- n_sectors -->
 *
 * Region 1 was already iterated over with bio_advance or similar function.
 *      (it may be empty if the target doesn't use bio_advance)
 * Region 2 is the remaining bio size that the target wants to process.
 *      (it may be empty if region 1 is non-empty, although there is no reason
 *       to make it empty)
 * The target requires that region 3 is to be sent in the next bio.
 *
 * If the target wants to receive multiple copies of the bio (via num_*bios, etc),
 * the partially processed part (the sum of regions 1+2) must be the same for all
 * copies of the bio.
 */


void dm_accept_partial_bio(struct bio *bio, unsigned n_sectors)
{
	struct dm_target_io *tio = container_of(bio, struct dm_target_io, clone);
	unsigned bi_size = bio->bi_iter.bi_size >> SECTOR_SHIFT;
	BUG_ON(bio->bi_rw & REQ_FLUSH);
	BUG_ON(bi_size > *tio->len_ptr);
	BUG_ON(n_sectors > bi_size);
	*tio->len_ptr -= bi_size - n_sectors;
	bio->bi_iter.bi_size = n_sectors << SECTOR_SHIFT;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
mikulas patocka
mikulas patocka
84
100.00%
1
100.00%
Total
84
100.00%
1
100.00%


EXPORT_SYMBOL_GPL(dm_accept_partial_bio);



static void __map_bio(struct dm_target_io *tio)
{
	int r;
	sector_t sector;
	struct bio *clone = &tio->clone;
	struct dm_target *ti = tio->ti;

	clone->bi_end_io = clone_endio;

	/*
         * Map the clone.  If r == 0 we don't need to do
         * anything, the target has assumed ownership of
         * this io.
         */
	atomic_inc(&tio->io->io_count);
	sector = clone->bi_iter.bi_sector;
	r = ti->type->map(ti, clone);
	if (r == DM_MAPIO_REMAPPED) {
		/* the bio has been remapped so dispatch it */

		trace_block_bio_remap(bdev_get_queue(clone->bi_bdev), clone,
				      tio->io->bio->bi_bdev->bd_dev, sector);

		generic_make_request(clone);
	} else if (r < 0 || r == DM_MAPIO_REQUEUE) {
		/* error the io and bail out, or requeue it if needed */
		dec_pending(tio->io, r);
		free_tio(tio);
	} else if (r != DM_MAPIO_SUBMITTED) {
		DMWARN("unimplemented target map return value: %d", r);
		BUG();
	}
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
kiyoshi ueda
kiyoshi ueda
92
57.86%
1
8.33%
alan cox
alan cox
17
10.69%
1
8.33%
mikulas patocka
mikulas patocka
13
8.18%
3
25.00%
jun'ichi nomura
jun'ichi nomura
10
6.29%
1
8.33%
joe thornber
joe thornber
10
6.29%
1
8.33%
alasdair kergon
alasdair kergon
9
5.66%
1
8.33%
andrew morton
andrew morton
4
2.52%
1
8.33%
kent overstreet
kent overstreet
2
1.26%
1
8.33%
stefan bader
stefan bader
1
0.63%
1
8.33%
mike snitzer
mike snitzer
1
0.63%
1
8.33%
Total
159
100.00%
12
100.00%


struct clone_info {
	
struct mapped_device *md;
	
struct dm_table *map;
	
struct bio *bio;
	
struct dm_io *io;
	
sector_t sector;
	
unsigned sector_count;
};



static void bio_setup_sector(struct bio *bio, sector_t sector, unsigned len)
{
	bio->bi_iter.bi_sector = sector;
	bio->bi_iter.bi_size = to_bytes(len);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
alasdair kergon
alasdair kergon
31
86.11%
1
33.33%
kent overstreet
kent overstreet
4
11.11%
1
33.33%
mikulas patocka
mikulas patocka
1
2.78%
1
33.33%
Total
36
100.00%
3
100.00%

/*
 * Creates a bio that consists of range of complete bvecs.
 */


static int clone_bio(struct dm_target_io *tio, struct bio *bio,
		     sector_t sector, unsigned len)
{
	struct bio *clone = &tio->clone;

	__bio_clone_fast(clone, bio);

	if (bio_integrity(bio)) {
		int r = bio_integrity_clone(clone, bio, GFP_NOIO);
		if (r < 0)
			return r;
	}

	bio_advance(clone, to_bytes(sector - clone->bi_iter.bi_sector));
	clone->bi_iter.bi_size = to_bytes(len);

	if (bio_integrity(bio))
		bio_integrity_trim(clone, 0, len);

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
kent overstreet
kent overstreet
54
46.96%
1
33.33%
alasdair kergon
alasdair kergon
42
36.52%
1
33.33%
mike snitzer
mike snitzer
19
16.52%
1
33.33%
Total
115
100.00%
3
100.00%



static struct dm_target_io *alloc_tio(struct clone_info *ci,
				      struct dm_target *ti,
				      unsigned target_bio_nr)
{
	struct dm_target_io *tio;
	struct bio *clone;

	clone = bio_alloc_bioset(GFP_NOIO, 0, ci->md->bs);
	tio = container_of(clone, struct dm_target_io, clone);

	tio->io = ci->io;
	tio->ti = ti;
	tio->target_bio_nr = target_bio_nr;

	return tio;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
kent overstreet
kent overstreet
42
51.85%
1
20.00%
kiyoshi ueda
kiyoshi ueda
31
38.27%
1
20.00%
mikulas patocka
mikulas patocka
4
4.94%
1
20.00%
alasdair kergon
alasdair kergon
3
3.70%
1
20.00%
jun'ichi nomura
jun'ichi nomura
1
1.23%
1
20.00%
Total
81
100.00%
5
100.00%



static void __clone_and_map_simple_bio(struct clone_info *ci,
				       struct dm_target *ti,
				       unsigned target_bio_nr, unsigned *len)
{
	struct dm_target_io *tio = alloc_tio(ci, ti, target_bio_nr);
	struct bio *clone = &tio->clone;

	tio->len_ptr = len;

	__bio_clone_fast(clone, ci->bio);
	if (len)
		bio_setup_sector(clone, ci->sector, *len);

	__map_bio(tio);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
kiyoshi ueda
kiyoshi ueda
37
44.58%
1
12.50%
mikulas patocka
mikulas patocka
21
25.30%
3
37.50%
mike snitzer
mike snitzer
13
15.66%
1
12.50%
kent overstreet
kent overstreet
6
7.23%
1
12.50%
alasdair kergon
alasdair kergon
6
7.23%
2
25.00%
Total
83
100.00%
8
100.00%



static void __send_duplicate_bios(struct clone_info *ci, struct dm_target *ti,
				  unsigned num_bios, unsigned *len)
{
	unsigned target_bio_nr;

	for (target_bio_nr = 0; target_bio_nr < num_bios; target_bio_nr++)
		__clone_and_map_simple_bio(ci, ti, target_bio_nr, len);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
39
78.00%
2
33.33%
alasdair kergon
alasdair kergon
9
18.00%
2
33.33%
mikulas patocka
mikulas patocka
2
4.00%
2
33.33%
Total
50
100.00%
6
100.00%



static int __send_empty_flush(struct clone_info *ci)
{
	unsigned target_nr = 0;
	struct dm_target *ti;

	BUG_ON(bio_has_data(ci->bio));
	while ((ti = dm_table_get_target(ci->map, target_nr++)))
		__send_duplicate_bios(ci, ti, ti->num_flush_bios, NULL);

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
kiyoshi ueda
kiyoshi ueda
46
73.02%
1
14.29%
mike snitzer
mike snitzer
13
20.63%
3
42.86%
alasdair kergon
alasdair kergon
3
4.76%
2
28.57%
mikulas patocka
mikulas patocka
1
1.59%
1
14.29%
Total
63
100.00%
7
100.00%



static int __clone_and_map_data_bio(struct clone_info *ci, struct dm_target *ti,
				     sector_t sector, unsigned *len)
{
	struct bio *bio = ci->bio;
	struct dm_target_io *tio;
	unsigned target_bio_nr;
	unsigned num_target_bios = 1;
	int r = 0;

	/*
         * Does the target want to receive duplicate copies of the bio?
         */
	if (bio_data_dir(bio) == WRITE && ti->num_write_bios)
		num_target_bios = ti->num_write_bios(ti, bio);

	for (target_bio_nr = 0; target_bio_nr < num_target_bios; target_bio_nr++) {
		tio = alloc_tio(ci, ti, target_bio_nr);
		tio->len_ptr = len;
		r = clone_bio(tio, bio, sector, *len);
		if (r < 0) {
			free_tio(tio);
			break;
		}
		__map_bio(tio);
	}

	return r;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
alasdair kergon
alasdair kergon
64
44.76%
3
37.50%
mike snitzer
mike snitzer
63
44.06%
2
25.00%
mikulas patocka
mikulas patocka
16
11.19%
3
37.50%
Total
143
100.00%
8
100.00%


typedef unsigned (*get_num_bios_fn)(struct dm_target *ti);



static unsigned get_num_discard_bios(struct dm_target *ti)
{
	return ti->num_discard_bios;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
14
87.50%
1
50.00%
alasdair kergon
alasdair kergon
2
12.50%
1
50.00%
Total
16
100.00%
2
100.00%



static unsigned get_num_write_same_bios(struct dm_target *ti)
{
	return ti->num_write_same_bios;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
14
87.50%
1
50.00%
alasdair kergon
alasdair kergon
2
12.50%
1
50.00%
Total
16
100.00%
2
100.00%


typedef bool (*is_split_required_fn)(struct dm_target *ti);



static bool is_split_required_for_discard(struct dm_target *ti)
{
	return ti->split_discard_bios;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
15
93.75%
1
50.00%
alasdair kergon
alasdair kergon
1
6.25%
1
50.00%
Total
16
100.00%
2
100.00%



static int __send_changing_extent_only(struct clone_info *ci,
				       get_num_bios_fn get_num_bios,
				       is_split_required_fn is_split_required)
{
	struct dm_target *ti;
	unsigned len;
	unsigned num_bios;

	do {
		ti = dm_table_find_target(ci->map, ci->sector);
		if (!dm_target_is_valid(ti))
			return -EIO;

		/*
                 * Even though the device advertised support for this type of
                 * request, that does not mean every target supports it, and
                 * reconfiguration might also have changed that since the
                 * check was performed.
                 */
		num_bios = get_num_bios ? get_num_bios(ti) : 0;
		if (!num_bios)
			return -EOPNOTSUPP;

		if (is_split_required && !is_split_required(ti))
			len = min((sector_t)ci->sector_count, max_io_len_target_boundary(ci->sector, ti));
		else
			len = min((sector_t)ci->sector_count, max_io_len(ci->sector, ti));

		__send_duplicate_bios(ci, ti, num_bios, &len);

		ci->sector += len;
	} while (ci->sector_count -= len);

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
108
67.50%
4
40.00%
mikulas patocka
mikulas patocka
32
20.00%
3
30.00%
alasdair kergon
alasdair kergon
20
12.50%
3
30.00%
Total
160
100.00%
10
100.00%



static int __send_discard(struct clone_info *ci)
{
	return __send_changing_extent_only(ci, get_num_discard_bios,
					   is_split_required_for_discard);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
18
85.71%
1
33.33%
alasdair kergon
alasdair kergon
3
14.29%
2
66.67%
Total
21
100.00%
3
100.00%



static int __send_write_same(struct clone_info *ci)
{
	return __send_changing_extent_only(ci, get_num_write_same_bios, NULL);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
18
85.71%
1
33.33%
alasdair kergon
alasdair kergon
3
14.29%
2
66.67%
Total
21
100.00%
3
100.00%

/*
 * Select the correct strategy for processing a non-flush bio.
 */


static int __split_and_process_non_flush(struct clone_info *ci)
{
	struct bio *bio = ci->bio;
	struct dm_target *ti;
	unsigned len;
	int r;

	if (unlikely(bio->bi_rw & REQ_DISCARD))
		return __send_discard(ci);
	else if (unlikely(bio->bi_rw & REQ_WRITE_SAME))
		return __send_write_same(ci);

	ti = dm_table_find_target(ci->map, ci->sector);
	if (!dm_target_is_valid(ti))
		return -EIO;

	len = min_t(sector_t, max_io_len(ci->sector, ti), ci->sector_count);

	r = __clone_and_map_data_bio(ci, ti, ci->sector, &len);
	if (r < 0)
		return r;

	ci->sector += len;
	ci->sector_count -= len;

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
kiyoshi ueda
kiyoshi ueda
80
52.98%
1
14.29%
alasdair kergon
alasdair kergon
48
31.79%
1
14.29%
mike snitzer
mike snitzer
16
10.60%
2
28.57%
kent overstreet
kent overstreet
5
3.31%
1
14.29%
mikulas patocka
mikulas patocka
2
1.32%
2
28.57%
Total
151
100.00%
7
100.00%

/*
 * Entry point to split a bio into clones and submit them to the targets.
 */


static void __split_and_process_bio(struct mapped_device *md,
				    struct dm_table *map, struct bio *bio)
{
	struct clone_info ci;
	int error = 0;

	if (unlikely(!map)) {
		bio_io_error(bio);
		return;
	}

	ci.map = map;
	ci.md = md;
	ci.io = alloc_io(md);
	ci.io->error = 0;
	atomic_set(&ci.io->io_count, 1);
	ci.io->bio = bio;
	ci.io->md = md;
	spin_lock_init(&ci.io->endio_lock);
	ci.sector = bio->bi_iter.bi_sector;

	start_io_acct(ci.io);

	if (bio->bi_rw & REQ_FLUSH) {
		ci.bio = &ci.md->flush_bio;
		ci.sector_count = 0;
		error = __send_empty_flush(&ci);
		/* dec_pending submits any data associated with flush */
	} else {
		ci.bio = bio;
		ci.sector_count = bio_sectors(bio);
		while (ci.sector_count && !error)
			error = __split_and_process_non_flush(&ci);
	}

	/* drop the extra reference count */
	dec_pending(ci.io, error);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
kiyoshi ueda
kiyoshi ueda
162
76.78%
2
25.00%
mike snitzer
mike snitzer
24
11.37%
1
12.50%
tejun heo
tejun heo
11
5.21%
2
25.00%
mikulas patocka
mikulas patocka
11
5.21%
1
12.50%
alasdair kergon
alasdair kergon
2
0.95%
1
12.50%
kent overstreet
kent overstreet
1
0.47%
1
12.50%
Total
211
100.00%
8
100.00%

/*-----------------------------------------------------------------
 * CRUD END
 *---------------------------------------------------------------*/

/*
 * The request function that just remaps the bio built up by
 * dm_merge_bvec.
 */


static blk_qc_t dm_make_request(struct request_queue *q, struct bio *bio)
{
	int rw = bio_data_dir(bio);
	struct mapped_device *md = q->queuedata;
	int srcu_idx;
	struct dm_table *map;

	map = dm_get_live_table(md, &srcu_idx);

	generic_start_io_acct(rw, bio_sectors(bio), &dm_disk(md)->part0);

	/* if we're suspended, we have to queue this io for later */
	if (unlikely(test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags))) {
		dm_put_live_table(md, srcu_idx);

		if (bio_rw(bio) != READA)
			queue_io(md, bio);
		else
			bio_io_error(bio);
		return BLK_QC_T_NONE;
	}

	__split_and_process_bio(md, map, bio);
	dm_put_live_table(md, srcu_idx);
	return BLK_QC_T_NONE;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
kiyoshi ueda
kiyoshi ueda
97
70.29%
1
16.67%
mikulas patocka
mikulas patocka
21
15.22%
1
16.67%
tejun heo
tejun heo
8
5.80%
1
16.67%
jens axboe
jens axboe
7
5.07%
1
16.67%
gu zheng
gu zheng
4
2.90%
1
16.67%
mike snitzer
mike snitzer
1
0.72%
1
16.67%
Total
138
100.00%
6
100.00%



int dm_request_based(struct mapped_device *md)
{
	return blk_queue_stackable(md->queue);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
kiyoshi ueda
kiyoshi ueda
17
94.44%
1
50.00%
alan cox
alan cox
1
5.56%
1
50.00%
Total
18
100.00%
2
100.00%



static void dm_dispatch_clone_request(struct request *clone, struct request *rq)
{
	int r;

	if (blk_queue_io_stat(clone->q))
		clone->cmd_flags |= REQ_IO_STAT;

	clone->start_time = jiffies;
	r = blk_insert_cloned_request(clone->q, clone);
	if (r)
		/* must complete clone in terms of original request */
		dm_complete_request(rq, r);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
kiyoshi ueda
kiyoshi ueda
48
76.19%
2
40.00%
keith busch
keith busch
12
19.05%
1
20.00%
joe thornber
joe thornber
2
3.17%
1
20.00%
mike snitzer
mike snitzer
1
1.59%
1
20.00%
Total
63
100.00%
5
100.00%



static int dm_rq_bio_constructor(struct bio *bio, struct bio *bio_orig,
				 void *data)
{
	struct dm_rq_target_io *tio = data;
	struct dm_rq_clone_bio_info *info =
		container_of(bio, struct dm_rq_clone_bio_info, clone);

	info->orig = bio_orig;
	info->tio = tio;
	bio->bi_end_io = end_clone_bio;

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
61
96.83%
1
33.33%
christoph hellwig
christoph hellwig
1
1.59%
1
33.33%
kiyoshi ueda
kiyoshi ueda
1
1.59%
1
33.33%
Total
63
100.00%
3
100.00%



static int setup_clone(struct request *clone, struct request *rq,
		       struct dm_rq_target_io *tio, gfp_t gfp_mask)
{
	int r;

	r = blk_rq_prep_clone(clone, rq, tio->md->bs, gfp_mask,
			      dm_rq_bio_constructor, tio);
	if (r)
		return r;

	clone->cmd = rq->cmd;
	clone->cmd_len = rq->cmd_len;
	clone->sense = rq->sense;
	clone->end_io = end_clone_request;
	clone->end_io_data = tio;

	tio->clone = clone;

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
62
62.00%
2
28.57%
kiyoshi ueda
kiyoshi ueda
34
34.00%
2
28.57%
alan cox
alan cox
2
2.00%
1
14.29%
joe thornber
joe thornber
1
1.00%
1
14.29%
alasdair kergon
alasdair kergon
1
1.00%
1
14.29%
Total
100
100.00%
7
100.00%



static struct request *clone_old_rq(struct request *rq, struct mapped_device *md,
				    struct dm_rq_target_io *tio, gfp_t gfp_mask)
{
	/*
         * Create clone for use with .request_fn request_queue
         */
	struct request *clone;

	clone = alloc_old_clone_request(md, gfp_mask);
	if (!clone)
		return NULL;

	blk_rq_init(NULL, clone);
	if (setup_clone(clone, rq, tio, gfp_mask)) {
		/* -ENOMEM */
		free_old_clone_request(md, clone);
		return NULL;
	}

	return clone;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
62
72.94%
5
83.33%
kiyoshi ueda
kiyoshi ueda
23
27.06%
1
16.67%
Total
85
100.00%
6
100.00%

static void map_tio_request(struct kthread_work *work);



static void init_tio(struct dm_rq_target_io *tio, struct request *rq,
		     struct mapped_device *md)
{
	tio->md = md;
	tio->ti = NULL;
	tio->clone = NULL;
	tio->orig = rq;
	tio->error = 0;
	/*
         * Avoid initializing info for blk-mq; it passes
         * target-specific data through info.ptr
         * (see: dm_mq_init_request)
         */
	if (!md->init_tio_pdu)
		memset(&tio->info, 0, sizeof(tio->info));
	if (md->kworker_task)
		init_kthread_work(&tio->work, map_tio_request);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
kiyoshi ueda
kiyoshi ueda
58
63.04%
1
14.29%
mike snitzer
mike snitzer
26
28.26%
4
57.14%
keith busch
keith busch
8
8.70%
2
28.57%
Total
92
100.00%
7
100.00%



static struct dm_rq_target_io *dm_old_prep_tio(struct request *rq,
					       struct mapped_device *md,
					       gfp_t gfp_mask)
{
	struct dm_rq_target_io *tio;
	int srcu_idx;
	struct dm_table *table;

	tio = alloc_old_rq_tio(md, gfp_mask);
	if (!tio)
		return NULL;

	init_tio(tio, rq, md);

	table = dm_get_live_table(md, &srcu_idx);
	/*
         * Must clone a request if this .request_fn DM device
         * is stacked on .request_fn device(s).
         */
	if (!dm_table_mq_request_based(table)) {
		if (!clone_old_rq(rq, md, tio, gfp_mask)) {
			dm_put_live_table(md, srcu_idx);
			free_old_rq_tio(tio);
			return NULL;
		}
	}
	dm_put_live_table(md, srcu_idx);

	return tio;
}

Contributors
Person
Tokens
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Commits
CommitProp
mike snitzer
mike snitzer
97
79.51%
4
66.67%
kiyoshi ueda
kiyoshi ueda
20
16.39%
1
16.67%
keith busch
keith busch
5
4.10%
1
16.67%
Total
122
100.00%
6
100.00%

/*
 * Called with the queue lock held.
 */


static int dm_old_prep_fn(struct request_queue *q, struct request *rq)
{
	struct mapped_device *md = q->queuedata;
	struct dm_rq_target_io *tio;

	if (unlikely(rq->special)) {
		DMWARN("Already has something in rq->special.");
		return BLKPREP_KILL;
	}

	tio = dm_old_prep_tio(rq, md, GFP_ATOMIC);
	if (!tio)
		return BLKPREP_DEFER;

	rq->special = tio;
	rq->cmd_flags |= REQ_DONTPREP;

	return BLKPREP_OK;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
kiyoshi ueda
kiyoshi ueda
54
65.06%
3
27.27%
alan cox
alan cox
11
13.25%
1
9.09%
mikulas patocka
mikulas patocka
8
9.64%
3
27.27%
keith busch
keith busch
5
6.02%
1
9.09%
jun'ichi nomura
jun'ichi nomura
2
2.41%
1
9.09%
mike snitzer
mike snitzer
2
2.41%
1
9.09%
andrew morton
andrew morton
1
1.20%
1
9.09%
Total
83
100.00%
11
100.00%

/*
 * Returns:
 * 0                : the request has been processed
 * DM_MAPIO_REQUEUE : the original request needs to be requeued
 * < 0              : the request was completed due to failure
 */


static int map_request(struct dm_rq_target_io *tio, struct request *rq,
		       struct mapped_device *md)
{
	int r;
	struct dm_target *ti = tio->ti;
	struct request *clone = NULL;

	if (tio->clone) {
		clone = tio->clone;
		r = ti->type->map_rq(ti, clone, &tio->info);
	} else {
		r = ti->type->clone_and_map_rq(ti, rq, &tio->info, &clone);
		if (r < 0) {
			/* The target wants to complete the I/O */
			dm_kill_unmapped_request(rq, r);
			return r;
		}
		if (r != DM_MAPIO_REMAPPED)
			return r;
		if (setup_clone(clone, rq, tio, GFP_ATOMIC)) {
			/* -ENOMEM */
			ti->type->release_clone_rq(clone);
			return DM_MAPIO_REQUEUE;
		}
	}

	switch (r) {
	case DM_MAPIO_SUBMITTED:
		/* The target has taken the I/O to submit by itself later */
		break;
	case DM_MAPIO_REMAPPED:
		/* The target has remapped the I/O so dispatch it */
		trace_block_rq_remap(clone->q, clone, disk_devt(dm_disk(md)),
				     blk_rq_pos(rq));
		dm_dispatch_clone_request(clone, rq);
		break;
	case DM_MAPIO_REQUEUE:
		/* The target wants to requeue the I/O */
		dm_requeue_original_request(md, tio->orig);
		break;
	default:
		if (r > 0) {
			DMWARN("unimplemented target map return value: %d", r);
			BUG();
		}

		/* The target wants to complete the I/O */
		dm_kill_unmapped_request(rq, r);
		return r;
	}

	return 0;
}

Contributors
Person
Tokens
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Commits
CommitProp
mike snitzer
mike snitzer
103
42.21%
4
28.57%
kiyoshi ueda
kiyoshi ueda
85
34.84%
2
14.29%
jun'ichi nomura
jun'ichi nomura
25
10.25%
2
14.29%
alan cox
alan cox
11
4.51%
1
7.14%
keith busch
keith busch
11
4.51%
1
7.14%
joe thornber
joe thornber
4
1.64%
2
14.29%
andrew morton
andrew morton
3
1.23%
1
7.14%
mikulas patocka
mikulas patocka
2
0.82%
1
7.14%
Total
244
100.00%
14
100.00%



static void map_tio_request(struct kthread_work *work)
{
	struct dm_rq_target_io *tio = container_of(work, struct dm_rq_target_io, work);
	struct request *rq = tio->orig;
	struct mapped_device *md = tio->md;

	if (map_request(tio, rq, md) == DM_MAPIO_REQUEUE)
		dm_requeue_original_request(md, rq);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
keith busch
keith busch
33
51.56%
1
25.00%
mike snitzer
mike snitzer
31
48.44%
3
75.00%
Total
64
100.00%
4
100.00%



static void dm_start_request(struct mapped_device *md, struct request *orig)
{
	if (!orig->q->mq_ops)
		blk_start_request(orig);
	else
		blk_mq_start_request(orig);
	atomic_inc(&md->pending[rq_data_dir(orig)]);

	if (md->seq_rq_merge_deadline_usecs) {
		md->last_rq_pos = rq_end_sector(orig);
		md->last_rq_rw = rq_data_dir(orig);
		md->last_rq_start_time = ktime_get();
	}

	if (unlikely(dm_stats_used(&md->stats))) {
		struct dm_rq_target_io *tio = tio_from_request(orig);
		tio->duration_jiffies = jiffies;
		tio->n_sectors = blk_rq_sectors(orig);
		dm_stats_account_io(&md->stats, orig->cmd_flags, blk_rq_pos(orig),
				    tio->n_sectors, false, 0, &tio->stats_aux);
	}

	/*
         * Hold the md reference here for the in-flight I/O.
         * We can't rely on the reference count by device opener,
         * because the device may be closed during the request completion
         * when all bios are completed.
         * See the comment in rq_completed() too.
         */
	dm_get(md);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
87
54.72%
4
66.67%
mikulas patocka
mikulas patocka
70
44.03%
1
16.67%
keith busch
keith busch
2
1.26%
1
16.67%
Total
159
100.00%
6
100.00%


#define MAX_SEQ_RQ_MERGE_DEADLINE_USECS 100000



ssize_t dm_attr_rq_based_seq_io_merge_deadline_show(struct mapped_device *md, char *buf)
{
	return sprintf(buf, "%u\n", md->seq_rq_merge_deadline_usecs);
}

Contributors
Person
Tokens
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Commits
CommitProp
mike snitzer
mike snitzer
26
100.00%
1
100.00%
Total
26
100.00%
1
100.00%



ssize_t dm_attr_rq_based_seq_io_merge_deadline_store(struct mapped_device *md,
						     const char *buf, size_t count)
{
	unsigned deadline;

	if (!dm_request_based(md) || md->use_blk_mq)
		return count;

	if (kstrtouint(buf, 10, &deadline))
		return -EINVAL;

	if (deadline > MAX_SEQ_RQ_MERGE_DEADLINE_USECS)
		deadline = MAX_SEQ_RQ_MERGE_DEADLINE_USECS;

	md->seq_rq_merge_deadline_usecs = deadline;

	return count;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
71
100.00%
2
100.00%
Total
71
100.00%
2
100.00%



static bool dm_request_peeked_before_merge_deadline(struct mapped_device *md)
{
	ktime_t kt_deadline;

	if (!md->seq_rq_merge_deadline_usecs)
		return false;

	kt_deadline = ns_to_ktime((u64)md->seq_rq_merge_deadline_usecs * NSEC_PER_USEC);
	kt_deadline = ktime_add_safe(md->last_rq_start_time, kt_deadline);

	return !ktime_after(ktime_get(), kt_deadline);
}

Contributors
Person
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CommitProp
mike snitzer
mike snitzer
59
100.00%
1
100.00%
Total
59
100.00%
1
100.00%

/*
 * q->request_fn for request-based dm.
 * Called with the queue lock held.
 */


static void dm_request_fn(struct request_queue *q)
{
	struct mapped_device *md = q->queuedata;
	struct dm_target *ti = md->immutable_target;
	struct request *rq;
	struct dm_rq_target_io *tio;
	sector_t pos = 0;

	if (unlikely(!ti)) {
		int srcu_idx;
		struct dm_table *map = dm_get_live_table(md, &srcu_idx);

		ti = dm_table_find_target(map, pos);
		dm_put_live_table(md, srcu_idx);
	}

	/*
         * For suspend, check blk_queue_stopped() and increment
         * ->pending within a single queue_lock not to increment the
         * number of in-flight I/Os after the queue is stopped in
         * dm_suspend().
         */
	while (!blk_queue_stopped(q)) {
		rq = blk_peek_request(q);
		if (!rq)
			return;

		/* always use block 0 to find the target for flushes for now */
		pos = 0;
		if (!(rq->cmd_flags & REQ_FLUSH))
			pos = blk_rq_pos(rq);

		if ((dm_request_peeked_before_merge_deadline(md) &&
		     md_in_flight(md) && rq->bio && rq->bio->bi_vcnt == 1 &&
		     md->last_rq_pos == pos && md->last_rq_rw == rq_data_dir(rq)) ||
		    (ti->type->busy && ti->type->busy(ti))) {
			blk_delay_queue(q, HZ / 100);
			return;
		}

		dm_start_request(md, rq);

		tio = tio_from_request(rq);
		/* Establish tio->ti before queuing work (map_tio_request) */
		tio->ti = ti;
		queue_kthread_work(&md->kworker, &tio->work);
		BUG_ON(!irqs_disabled());
	}
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
108
44.26%
5
38.46%
kiyoshi ueda
kiyoshi ueda
50
20.49%
4
30.77%
milan broz
milan broz
43
17.62%
1
7.69%
keith busch
keith busch
23
9.43%
1
7.69%
tejun heo
tejun heo
17
6.97%
1
7.69%
mikulas patocka
mikulas patocka
3
1.23%
1
7.69%
Total
244
100.00%
13
100.00%



static int dm_any_congested(void *congested_data, int bdi_bits)
{
	int r = bdi_bits;
	struct mapped_device *md = congested_data;
	struct dm_table *map;

	if (!test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) {
		if (dm_request_based(md)) {
			/*
                         * With request-based DM we only need to check the
                         * top-level queue for congestion.
                         */
			r = md->queue->backing_dev_info.wb.state & bdi_bits;
		} else {
			map = dm_get_live_table_fast(md);
			if (map)
				r = dm_table_any_congested(map, bdi_bits);
			dm_put_live_table_fast(md);
		}
	}

	return r;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
andrew morton
andrew morton
54
54.00%
1
14.29%
kiyoshi ueda
kiyoshi ueda
20
20.00%
1
14.29%
mike snitzer
mike snitzer
16
16.00%
1
14.29%
chandra seetharaman
chandra seetharaman
5
5.00%
1
14.29%
mikulas patocka
mikulas patocka
2
2.00%
1
14.29%
tejun heo
tejun heo
2
2.00%
1
14.29%
alasdair kergon
alasdair kergon
1
1.00%
1
14.29%
Total
100
100.00%
7
100.00%

/*-----------------------------------------------------------------
 * An IDR is used to keep track of allocated minor numbers.
 *---------------------------------------------------------------*/


static void free_minor(int minor)
{
	spin_lock(&_minor_lock);
	idr_remove(&_minor_idr, minor);
	spin_unlock(&_minor_lock);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
alan cox
alan cox
23
79.31%
1
33.33%
kevin corry
kevin corry
4
13.79%
1
33.33%
jeff mahoney
jeff mahoney
2
6.90%
1
33.33%
Total
29
100.00%
3
100.00%

/*
 * See if the device with a specific minor # is free.
 */


static int specific_minor(int minor)
{
	int r;

	if (minor >= (1 << MINORBITS))
		return -EINVAL;

	idr_preload(GFP_KERNEL);
	spin_lock(&_minor_lock);

	r = idr_alloc(&_minor_idr, MINOR_ALLOCED, minor, minor + 1, GFP_NOWAIT);

	spin_unlock(&_minor_lock);
	idr_preload_end();
	if (r < 0)
		return r == -ENOSPC ? -EBUSY : r;
	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
alan cox
alan cox
28
33.33%
2
22.22%
tejun heo
tejun heo
25
29.76%
1
11.11%
kevin corry
kevin corry
23
27.38%
2
22.22%
jeff mahoney
jeff mahoney
7
8.33%
3
33.33%
alasdair kergon
alasdair kergon
1
1.19%
1
11.11%
Total
84
100.00%
9
100.00%



static int next_free_minor(int *minor)
{
	int r;

	idr_preload(GFP_KERNEL);
	spin_lock(&_minor_lock);

	r = idr_alloc(&_minor_idr, MINOR_ALLOCED, 0, 1 << MINORBITS, GFP_NOWAIT);

	spin_unlock(&_minor_lock);
	idr_preload_end();
	if (r < 0)
		return r;
	*minor = r;
	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
tejun heo
tejun heo
22
32.35%
1
11.11%
alan cox
alan cox
19
27.94%
2
22.22%
kevin corry
kevin corry
16
23.53%
2
22.22%
jeff mahoney
jeff mahoney
7
10.29%
3
33.33%
joe thornber
joe thornber
4
5.88%
1
11.11%
Total
68
100.00%
9
100.00%


static const struct block_device_operations dm_blk_dops;

static void dm_wq_work(struct work_struct *work);



static void dm_init_md_queue(struct mapped_device *md)
{
	/*
         * Request-based dm devices cannot be stacked on top of bio-based dm
         * devices.  The type of this dm device may not have been decided yet.
         * The type is decided at the first table loading time.
         * To prevent problematic device stacking, clear the queue flag
         * for request stacking support until then.
         *
         * This queue is new, so no concurrency on the queue_flags.
         */
	queue_flag_clear_unlocked(QUEUE_FLAG_STACKABLE, md->queue);

	/*
         * Initialize data that will only be used by a non-blk-mq DM queue
         * - must do so here (in alloc_dev callchain) before queue is used
         */
	md->queue->queuedata = md;
	md->queue->backing_dev_info.congested_data = md;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
21
52.50%
2
66.67%
mikulas patocka
mikulas patocka
19
47.50%
1
33.33%
Total
40
100.00%
3
100.00%



static void dm_init_normal_md_queue(struct mapped_device *md)
{
	md->use_blk_mq = false;
	dm_init_md_queue(md);

	/*
         * Initialize aspects of queue that aren't relevant for blk-mq
         */
	md->queue->backing_dev_info.congested_fn = dm_any_congested;
	blk_queue_bounce_limit(md->queue, BLK_BOUNCE_ANY);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
42
100.00%
4
100.00%
Total
42
100.00%
4
100.00%



static void cleanup_mapped_device(struct mapped_device *md)
{
	if (md->wq)
		destroy_workqueue(md->wq);
	if (md->kworker_task)
		kthread_stop(md->kworker_task);
	mempool_destroy(md->io_pool);
	mempool_destroy(md->rq_pool);
	if (md->bs)
		bioset_free(md->bs);

	cleanup_srcu_struct(&md->io_barrier);

	if (md->disk) {
		spin_lock(&_minor_lock);
		md->disk->private_data = NULL;
		spin_unlock(&_minor_lock);
		del_gendisk(md->disk);
		put_disk(md->disk);
	}

	if (md->queue)
		blk_cleanup_queue(md->queue);

	if (md->bdev) {
		bdput(md->bdev);
		md->bdev = NULL;
	}
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
134
90.54%
1
33.33%
mikulas patocka
mikulas patocka
8
5.41%
1
33.33%
alan cox
alan cox
6
4.05%
1
33.33%
Total
148
100.00%
3
100.00%

/*
 * Allocate and initialise a blank device with a given minor.
 */


static struct mapped_device *alloc_dev(int minor)
{
	int r, numa_node_id = dm_get_numa_node();
	struct mapped_device *md;
	void *old_md;

	md = kzalloc_node(sizeof(*md), GFP_KERNEL, numa_node_id);
	if (!md) {
		DMWARN("unable to allocate device, out of memory.");
		return NULL;
	}

	if (!try_module_get(THIS_MODULE))
		goto bad_module_get;

	/* get a minor number for the dev */
	if (minor == DM_ANY_MINOR)
		r = next_free_minor(&minor);
	else
		r = specific_minor(minor);
	if (r < 0)
		goto bad_minor;

	r = init_srcu_struct(&md->io_barrier);
	if (r < 0)
		goto bad_io_barrier;

	md->numa_node_id = numa_node_id;
	md->use_blk_mq = use_blk_mq;
	md->init_tio_pdu = false;
	md->type = DM_TYPE_NONE;
	mutex_init(&md->suspend_lock);
	mutex_init(&md->type_lock);
	mutex_init(&md->table_devices_lock);
	spin_lock_init(&md->deferred_lock);
	atomic_set(&md->holders, 1);
	atomic_set(&md->open_count, 0);
	atomic_set(&md->event_nr, 0);
	atomic_set(&md->uevent_seq, 0);
	INIT_LIST_HEAD(&md->uevent_list);
	INIT_LIST_HEAD(&md->table_devices);
	spin_lock_init(&md->uevent_lock);

	md->queue = blk_alloc_queue_node(GFP_KERNEL, numa_node_id);
	if (!md->queue)
		goto bad;

	dm_init_md_queue(md);

	md->disk = alloc_disk_node(1, numa_node_id);
	if (!md->disk)
		goto bad;

	atomic_set(&md->pending[0], 0);
	atomic_set(&md->pending[1], 0);
	init_waitqueue_head(&md->wait);
	INIT_WORK(&md->work, dm_wq_work);
	init_waitqueue_head(&md->eventq);
	init_completion(&md->kobj_holder.completion);
	md->kworker_task = NULL;

	md->disk->major = _major;
	md->disk->first_minor = minor;
	md->disk->fops = &dm_blk_dops;
	md->disk->queue = md->queue;
	md->disk->private_data = md;
	sprintf(md->disk->disk_name, "dm-%d", minor);
	add_disk(md->disk);
	format_dev_t(md->name, MKDEV(_major, minor));

	md->wq = alloc_workqueue("kdmflush", WQ_MEM_RECLAIM, 0);
	if (!md->wq)
		goto bad;

	md->bdev = bdget_disk(md->disk, 0);
	if (!md->bdev)
		goto bad;

	bio_init(&md->flush_bio);
	md->flush_bio.bi_bdev = md->bdev;
	md->flush_bio.bi_rw = WRITE_FLUSH;

	dm_stats_init(&md->stats);

	/* Populate the mapping, nobody knows we exist yet */
	spin_lock(&_minor_lock);
	old_md = idr_replace(&_minor_idr, md, minor);
	spin_unlock(&_minor_lock);

	BUG_ON(old_md != MINOR_ALLOCED);

	return md;

bad:
	cleanup_mapped_device(md);
bad_io_barrier:
	free_minor(minor);
bad_minor:
	module_put(THIS_MODULE);
bad_module_get:
	kfree(md);
	return NULL;
}

Contributors
Person
Tokens
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CommitProp
alan cox
alan cox
150
25.95%
1
2.50%
mikulas patocka
mikulas patocka
75
12.98%
7
17.50%
jeff mahoney
jeff mahoney
74
12.80%
4
10.00%
mike snitzer
mike snitzer
57
9.86%
6
15.00%
mike anderson
mike anderson
40
6.92%
2
5.00%
tejun heo
tejun heo
31
5.36%
3
7.50%
alasdair kergon
alasdair kergon
30
5.19%
3
7.50%
andrew morton
andrew morton
30
5.19%
2
5.00%
milan broz
milan broz
21
3.63%
2
5.00%
benjamin marzinski
benjamin marzinski
16
2.77%
1
2.50%
nikanth karthikesan
nikanth karthikesan
16
2.77%
1
2.50%
jens axboe
jens axboe
11
1.90%
1
2.50%
kiyoshi ueda
kiyoshi ueda
9
1.56%
2
5.00%
joe thornber
joe thornber
8
1.38%
1
2.50%
keith busch
keith busch
6
1.04%
1
2.50%
stefan bader
stefan bader
2
0.35%
1
2.50%
ishai rabinovitz
ishai rabinovitz
1
0.17%
1
2.50%
daniel walker
daniel walker
1
0.17%
1
2.50%
Total
578
100.00%
40
100.00%

static void unlock_fs(struct mapped_device *md);



static void free_dev(struct mapped_device *md)
{
	int minor = MINOR(disk_devt(md->disk));

	unlock_fs(md);

	cleanup_mapped_device(md);
	if (md->tag_set) {
		blk_mq_free_tag_set(md->tag_set);
		kfree(md->tag_set);
	}

	free_table_devices(&md->table_devices);
	dm_stats_cleanup(&md->stats);
	free_minor(minor);

	module_put(THIS_MODULE);
	kfree(md);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
40
45.98%
5
38.46%
alan cox
alan cox
19
21.84%
1
7.69%
jun'ichi nomura
jun'ichi nomura
6
6.90%
2
15.38%
mikulas patocka
mikulas patocka
5
5.75%
1
7.69%
benjamin marzinski
benjamin marzinski
5
5.75%
1
7.69%
jeff mahoney
jeff mahoney
5
5.75%
1
7.69%
jens axboe
jens axboe
4
4.60%
1
7.69%
tejun heo
tejun heo
3
3.45%
1
7.69%
Total
87
100.00%
13
100.00%



static void __bind_mempools(struct mapped_device *md, struct dm_table *t)
{
	struct dm_md_mempools *p = dm_table_get_md_mempools(t);

	if (md->bs) {
		/* The md already has necessary mempools. */
		if (dm_table_get_type(t) == DM_TYPE_BIO_BASED) {
			/*
                         * Reload bioset because front_pad may have changed
                         * because a different table was loaded.
                         */
			bioset_free(md->bs);
			md->bs = p->bs;
			p->bs = NULL;
		}
		/*
                 * There's no need to reload with request-based dm
                 * because the size of front_pad doesn't change.
                 * Note for future: If you are to reload bioset,
                 * prep-ed requests in the queue may refer
                 * to bio from the old bioset, so you must walk
                 * through the queue to unprep.
                 */
		goto out;
	}

	BUG_ON(!p || md->io_pool || md->rq_pool || md->bs);

	md->io_pool = p->io_pool;
	p->io_pool = NULL;
	md->rq_pool = p->rq_pool;
	p->rq_pool = NULL;
	md->bs = p->bs;
	p->bs = NULL;

out:
	/* mempool bind completed, no longer need any mempools in the table */
	dm_table_free_md_mempools(t);
}

Contributors
Person
Tokens
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Commits
CommitProp
kiyoshi ueda
kiyoshi ueda
60
42.86%
1
14.29%
mike snitzer
mike snitzer
50
35.71%
4
57.14%
mikulas patocka
mikulas patocka
28
20.00%
1
14.29%
jun'ichi nomura
jun'ichi nomura
2
1.43%
1
14.29%
Total
140
100.00%
7
100.00%

/*
 * Bind a table to the device.
 */


static void event_callback(void *context)
{
	unsigned long flags;
	LIST_HEAD(uevents);
	struct mapped_device *md = (struct mapped_device *) context;

	spin_lock_irqsave(&md->uevent_lock, flags);
	list_splice_init(&md->uevent_list, &uevents);
	spin_unlock_irqrestore(&md->uevent_lock, flags);

	dm_send_uevents(&uevents, &disk_to_dev(md->disk)->kobj);

	atomic_inc(&md->event_nr);
	wake_up(&md->eventq);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike anderson
mike anderson
53
56.38%
1
20.00%
andrew morton
andrew morton
38
40.43%
3
60.00%
tejun heo
tejun heo
3
3.19%
1
20.00%
Total
94
100.00%
5
100.00%

/*
 * Protected by md->suspend_lock obtained by dm_swap_table().
 */


static void __set_size(struct mapped_device *md, sector_t size)
{
	set_capacity(md->disk, size);

	i_size_write(md->bdev->bd_inode, (loff_t)size << SECTOR_SHIFT);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
andrew morton
andrew morton
29
74.36%
1
25.00%
alasdair kergon
alasdair kergon
6
15.38%
1
25.00%
joe thornber
joe thornber
3
7.69%
1
25.00%
mikulas patocka
mikulas patocka
1
2.56%
1
25.00%
Total
39
100.00%
4
100.00%

/*
 * Returns old map, which caller must destroy.
 */


static struct dm_table *__bind(struct mapped_device *md, struct dm_table *t,
			       struct queue_limits *limits)
{
	struct dm_table *old_map;
	struct request_queue *q = md->queue;
	sector_t size;

	size = dm_table_get_size(t);

	/*
         * Wipe any geometry if the size of the table changed.
         */
	if (size != dm_get_size(md))
		memset(&md->geometry, 0, sizeof(md->geometry));

	__set_size(md, size);

	dm_table_event_callback(t, event_callback, md);

	/*
         * The queue hasn't been stopped yet, if the old table type wasn't
         * for request-based during suspension.  So stop it to prevent
         * I/O mapping before resume.
         * This must be done before setting the queue restrictions,
         * because request-based dm may be run just after the setting.
         */
	if (dm_table_request_based(t)) {
		dm_stop_queue(q);
		/*
                 * Leverage the fact that request-based DM targets are
                 * immutable singletons and establish md->immutable_target
                 * - used to optimize both dm_request_fn and dm_mq_queue_rq
                 */
		md->immutable_target = dm_table_get_immutable_target(t);
	}

	__bind_mempools(md, t);

	old_map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock));
	rcu_assign_pointer(md->map, (void *)t);
	md->immutable_target_type = dm_table_get_immutable_target_type(t);

	dm_table_set_restrictions(t, q, limits);
	if (old_map)
		dm_sync_table(md);

	return old_map;
}

Contributors
Person
Tokens
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CommitProp
alan cox
alan cox
43
23.63%
1
4.55%
alasdair kergon
alasdair kergon
38
20.88%
4
18.18%
darrick j. wong
darrick j. wong
26
14.29%
1
4.55%
mike snitzer
mike snitzer
24
13.19%
4
18.18%
kiyoshi ueda
kiyoshi ueda
19
10.44%
1
4.55%
andrew morton
andrew morton
9
4.95%
4
18.18%
eric dumazet
eric dumazet
9
4.95%
1
4.55%
mikulas patocka
mikulas patocka
8
4.40%
3
13.64%
pranith kumar
pranith kumar
2
1.10%
1
4.55%
jens axboe
jens axboe
2
1.10%
1
4.55%
hannes reinecke
hannes reinecke
2
1.10%
1
4.55%
Total
182
100.00%
22
100.00%

/*
 * Returns unbound table for the caller to free.
 */


static struct dm_table *__unbind(struct mapped_device *md)
{
	struct dm_table *map = rcu_dereference_protected(md->map, 1);

	if (!map)
		return NULL;

	dm_table_event_callback(map, NULL, NULL);
	RCU_INIT_POINTER(md->map, NULL);
	dm_sync_table(md);

	return map;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
andrew morton
andrew morton
28
45.90%
3
33.33%
alan cox
alan cox
16
26.23%
1
11.11%
alasdair kergon
alasdair kergon
8
13.11%
1
11.11%
eric dumazet
eric dumazet
3
4.92%
1
11.11%
mikulas patocka
mikulas patocka
3
4.92%
1
11.11%
pranith kumar
pranith kumar
2
3.28%
1
11.11%
monam agarwal
monam agarwal
1
1.64%
1
11.11%
Total
61
100.00%
9
100.00%

/*
 * Constructor for a new device.
 */


int dm_create(int minor, struct mapped_device **result)
{
	struct mapped_device *md;

	md = alloc_dev(minor);
	if (!md)
		return -ENXIO;

	dm_sysfs_init(md);

	*result = md;
	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
alan cox
alan cox
42
87.50%
1
33.33%
milan broz
milan broz
5
10.42%
1
33.33%
alasdair kergon
alasdair kergon
1
2.08%
1
33.33%
Total
48
100.00%
3
100.00%

/*
 * Functions to manage md->type.
 * All are required to hold md->type_lock.
 */


void dm_lock_md_type(struct mapped_device *md)
{
	mutex_lock(&md->type_lock);
}

Contributors
Person
Tokens
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CommitProp
mike snitzer
mike snitzer
18
100.00%
1
100.00%
Total
18
100.00%
1
100.00%



void dm_unlock_md_type(struct mapped_device *md)
{
	mutex_unlock(&md->type_lock);
}

Contributors
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CommitProp
mike snitzer
mike snitzer
18
100.00%
1
100.00%
Total
18
100.00%
1
100.00%



void dm_set_md_type(struct mapped_device *md, unsigned type)
{
	BUG_ON(!mutex_is_locked(&md->type_lock));
	md->type = type;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
31
100.00%
2
100.00%
Total
31
100.00%
2
100.00%



unsigned dm_get_md_type(struct mapped_device *md)
{
	return md->type;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
15
100.00%
1
100.00%
Total
15
100.00%
1
100.00%



struct target_type *dm_get_immutable_target_type(struct mapped_device *md)
{
	return md->immutable_target_type;
}

Contributors
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alasdair kergon
alasdair kergon
17
100.00%
1
100.00%
Total
17
100.00%
1
100.00%

/*
 * The queue_limits are only valid as long as you have a reference
 * count on 'md'.
 */


struct queue_limits *dm_get_queue_limits(struct mapped_device *md)
{
	BUG_ON(!atomic_read(&md->holders));
	return &md->queue->limits;
}
Contributors
Person
Tokens
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CommitProp
mike snitzer
mike snitzer
32
100.00%
1
100.00%
Total
32
100.00%
1
100.00%


EXPORT_SYMBOL_GPL(dm_get_queue_limits);



static void dm_old_init_rq_based_worker_thread(struct mapped_device *md)
{
	/* Initialize the request-based DM worker thread */
	init_kthread_worker(&md->kworker);
	md->kworker_task = kthread_run(kthread_worker_fn, &md->kworker,
				       "kdmwork-%s", dm_device_name(md));
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
41
100.00%
2
100.00%
Total
41
100.00%
2
100.00%

/*
 * Fully initialize a .request_fn request-based queue.
 */


static int dm_old_init_request_queue(struct mapped_device *md)
{
	/* Fully initialize the queue */
	if (!blk_init_allocated_queue(md->queue, dm_request_fn, NULL))
		return -EINVAL;

	/* disable dm_request_fn's merge heuristic by default */
	md->seq_rq_merge_deadline_usecs = 0;

	dm_init_normal_md_queue(md);
	blk_queue_softirq_done(md->queue, dm_softirq_done);
	blk_queue_prep_rq(md->queue, dm_old_prep_fn);

	dm_old_init_rq_based_worker_thread(md);

	elv_register_queue(md->queue);

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
68
90.67%
4
66.67%
keith busch
keith busch
4
5.33%
1
16.67%
bob liu
bob liu
3
4.00%
1
16.67%
Total
75
100.00%
6
100.00%



static int dm_mq_init_request(void *data, struct request *rq,
			      unsigned int hctx_idx, unsigned int request_idx,
			      unsigned int numa_node)
{
	struct mapped_device *md = data;
	struct dm_rq_target_io *tio = blk_mq_rq_to_pdu(rq);

	/*
         * Must initialize md member of tio, otherwise it won't
         * be available in dm_mq_queue_rq.
         */
	tio->md = md;

	if (md->init_tio_pdu) {
		/* target-specific per-io data is immediately after the tio */
		tio->info.ptr = tio + 1;
	}

	return 0;
}

Contributors
Person
Tokens
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Commits
CommitProp
mike snitzer
mike snitzer
73
100.00%
3
100.00%
Total
73
100.00%
3
100.00%



static int dm_mq_queue_rq(struct blk_mq_hw_ctx *hctx,
			  const struct blk_mq_queue_data *bd)
{
	struct request *rq = bd->rq;
	struct dm_rq_target_io *tio = blk_mq_rq_to_pdu(rq);
	struct mapped_device *md = tio->md;
	struct dm_target *ti = md->immutable_target;

	if (unlikely(!ti)) {
		int srcu_idx;
		struct dm_table *map = dm_get_live_table(md, &srcu_idx);

		ti = dm_table_find_target(map, 0);
		dm_put_live_table(md, srcu_idx);
	}

	if (ti->type->busy && ti->type->busy(ti))
		return BLK_MQ_RQ_QUEUE_BUSY;

	dm_start_request(md, rq);

	/* Init tio using md established in .init_request */
	init_tio(tio, rq, md);

	/*
         * Establish tio->ti before queuing work (map_tio_request)
         * or making direct call to map_request().
         */
	tio->ti = ti;

	/* Direct call is fine since .queue_rq allows allocations */
	if (map_request(tio, rq, md) == DM_MAPIO_REQUEUE) {
		/* Undo dm_start_request() before requeuing */
		rq_end_stats(md, rq);
		rq_completed(md, rq_data_dir(rq), false);
		return BLK_MQ_RQ_QUEUE_BUSY;
	}

	return BLK_MQ_RQ_QUEUE_OK;
}

Contributors
Person
Tokens
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Commits
CommitProp
mike snitzer
mike snitzer
175
96.15%
5
83.33%
mikulas patocka
mikulas patocka
7
3.85%
1
16.67%
Total
182
100.00%
6
100.00%


static struct blk_mq_ops dm_mq_ops = {
	.queue_rq = dm_mq_queue_rq,
	.map_queue = blk_mq_map_queue,
	.complete = dm_softirq_done,
	.init_request = dm_mq_init_request,
};



static int dm_mq_init_request_queue(struct mapped_device *md,
				    struct dm_target *immutable_tgt)
{
	struct request_queue *q;
	int err;

	if (dm_get_md_type(md) == DM_TYPE_REQUEST_BASED) {
		DMERR("request-based dm-mq may only be stacked on blk-mq device(s)");
		return -EINVAL;
	}

	md->tag_set = kzalloc_node(sizeof(struct blk_mq_tag_set), GFP_KERNEL, md->numa_node_id);
	if (!md->tag_set)
		return -ENOMEM;

	md->tag_set->ops = &dm_mq_ops;
	md->tag_set->queue_depth = dm_get_blk_mq_queue_depth();
	md->tag_set->numa_node = md->numa_node_id;
	md->tag_set->flags = BLK_MQ_F_SHOULD_MERGE | BLK_MQ_F_SG_MERGE;
	md->tag_set->nr_hw_queues = dm_get_blk_mq_nr_hw_queues();
	md->tag_set->driver_data = md;

	md->tag_set->cmd_size = sizeof(struct dm_rq_target_io);
	if (immutable_tgt && immutable_tgt->per_io_data_size) {
		/* any target-specific per-io data is immediately after the tio */
		md->tag_set->cmd_size += immutable_tgt->per_io_data_size;
		md->init_tio_pdu = true;
	}

	err = blk_mq_alloc_tag_set(md->tag_set);
	if (err)
		goto out_kfree_tag_set;

	q = blk_mq_init_allocated_queue(md->tag_set, md->queue);
	if (IS_ERR(q)) {
		err = PTR_ERR(q);
		goto out_tag_set;
	}
	dm_init_md_queue(md);

	/* backfill 'mq' sysfs registration normally done in blk_register_queue */
	blk_mq_register_disk(md->disk);

	return 0;

out_tag_set:
	blk_mq_free_tag_set(md->tag_set);
out_kfree_tag_set:
	kfree(md->tag_set);

	return err;
}

Contributors
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mike snitzer
mike snitzer
253
100.00%
8
100.00%
Total
253
100.00%
8
100.00%



static unsigned filter_md_type(unsigned type, struct mapped_device *md)
{
	if (type == DM_TYPE_BIO_BASED)
		return type;

	return !md->use_blk_mq ? DM_TYPE_REQUEST_BASED : DM_TYPE_MQ_REQUEST_BASED;
}

Contributors
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mike snitzer
mike snitzer
33
100.00%
1
100.00%
Total
33
100.00%
1
100.00%

/*
 * Setup the DM device's queue based on md's type
 */


int dm_setup_md_queue(struct mapped_device *md, struct dm_table *t)
{
	int r;
	unsigned md_type = filter_md_type(dm_get_md_type(md), md);

	switch (md_type) {
	case DM_TYPE_REQUEST_BASED:
		r = dm_old_init_request_queue(md);
		if (r) {
			DMERR("Cannot initialize queue for request-based mapped device");
			return r;
		}
		break;
	case DM_TYPE_MQ_REQUEST_BASED:
		r = dm_mq_init_request_queue(md, dm_table_get_immutable_target(t));
		if (r) {
			DMERR("Cannot initialize queue for request-based dm-mq mapped device");
			return r;
		}
		break;
	case DM_TYPE_BIO_BASED:
		dm_init_normal_md_queue(md);
		blk_queue_make_request(md->queue, dm_make_request);
		/*
                 * DM handles splitting bios as needed.  Free the bio_split bioset
                 * since it won't be used (saves 1 process per bio-based DM device).
                 */
		bioset_free(md->queue->bio_split);
		md->queue->bio_split = NULL;
		break;
	}

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
113
86.26%
6
85.71%
mikulas patocka
mikulas patocka
18
13.74%
1
14.29%
Total
131
100.00%
7
100.00%



struct mapped_device *dm_get_md(dev_t dev)
{
	struct mapped_device *md;
	unsigned minor = MINOR(dev);

	if (MAJOR(dev) != _major || minor >= (1 << MINORBITS))
		return NULL;

	spin_lock(&_minor_lock);

	md = idr_find(&_minor_idr, minor);
	if (md) {
		if ((md == MINOR_ALLOCED ||
		     (MINOR(disk_devt(dm_disk(md))) != minor) ||
		     dm_deleting_md(md) ||
		     test_bit(DMF_FREEING, &md->flags))) {
			md = NULL;
			goto out;
		}
		dm_get(md);
	}

out:
	spin_unlock(&_minor_lock);

	return md;
}
Contributors
Person
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alasdair kergon
alasdair kergon
72
56.25%
1
11.11%
jeff mahoney
jeff mahoney
24
18.75%
3
33.33%
mikulas patocka
mikulas patocka
11
8.59%
1
11.11%
david teigland
david teigland
10
7.81%
2
22.22%
tejun heo
tejun heo
6
4.69%
1
11.11%
kiyoshi ueda
kiyoshi ueda
5
3.91%
1
11.11%
Total
128
100.00%
9
100.00%


EXPORT_SYMBOL_GPL(dm_get_md);



void *dm_get_mdptr(struct mapped_device *md)
{
	return md->interface_ptr;
}

Contributors
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CommitProp
david teigland
david teigland
11
68.75%
1
33.33%
alasdair kergon
alasdair kergon
5
31.25%
2
66.67%
Total
16
100.00%
3
100.00%



void dm_set_mdptr(struct mapped_device *md, void *ptr)
{
	md->interface_ptr = ptr;
}

Contributors
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alasdair kergon
alasdair kergon
20
100.00%
1
100.00%
Total
20
100.00%
1
100.00%



void dm_get(struct mapped_device *md)
{
	atomic_inc(&md->holders);
	BUG_ON(test_bit(DMF_FREEING, &md->flags));
}

Contributors
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alan cox
alan cox
18
58.06%
1
50.00%
kiyoshi ueda
kiyoshi ueda
13
41.94%
1
50.00%
Total
31
100.00%
2
100.00%



int dm_hold(struct mapped_device *md)
{
	spin_lock(&_minor_lock);
	if (test_bit(DMF_FREEING, &md->flags)) {
		spin_unlock(&_minor_lock);
		return -EBUSY;
	}
	dm_get(md);
	spin_unlock(&_minor_lock);
	return 0;
}
Contributors
Person
Tokens
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Commits
CommitProp
mikulas patocka
mikulas patocka
54
100.00%
1
100.00%
Total
54
100.00%
1
100.00%


EXPORT_SYMBOL_GPL(dm_hold);



const char *dm_device_name(struct mapped_device *md)
{
	return md->name;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
alasdair kergon
alasdair kergon
17
100.00%
1
100.00%
Total
17
100.00%
1
100.00%


EXPORT_SYMBOL_GPL(dm_device_name);



static void __dm_destroy(struct mapped_device *md, bool wait)
{
	struct dm_table *map;
	int srcu_idx;

	might_sleep();

	spin_lock(&_minor_lock);
	idr_replace(&_minor_idr, MINOR_ALLOCED, MINOR(disk_devt(dm_disk(md))));
	set_bit(DMF_FREEING, &md->flags);
	spin_unlock(&_minor_lock);

	if (dm_request_based(md) && md->kworker_task)
		flush_kthread_worker(&md->kworker);

	/*
         * Take suspend_lock so that presuspend and postsuspend methods
         * do not race with internal suspend.
         */
	mutex_lock(&md->suspend_lock);
	map = dm_get_live_table(md, &srcu_idx);
	if (!dm_suspended_md(md)) {
		dm_table_presuspend_targets(map);
		dm_table_postsuspend_targets(map);
	}
	/* dm_put_live_table must be before msleep, otherwise deadlock is possible */
	dm_put_live_table(md, srcu_idx);
	mutex_unlock(&md->suspend_lock);

	/*
         * Rare, but there may be I/O requests still going to complete,
         * for example.  Wait for all references to disappear.
         * No one should increment the reference count of the mapped_device,
         * after the mapped_device state becomes DMF_FREEING.
         */
	if (wait)
		while (atomic_read(&md->holders))
			msleep(1);
	else if (atomic_read(&md->holders))
		DMWARN("%s: Forcibly removing mapped_device still in use! (%d users)",
		       dm_device_name(md), atomic_read(&md->holders));

	dm_sysfs_exit(md);
	dm_table_destroy(__unbind(md));
	free_dev(md);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
kiyoshi ueda
kiyoshi ueda
57
27.54%
2
10.00%
jeff mahoney
jeff mahoney
30
14.49%
3
15.00%
mikulas patocka
mikulas patocka
22
10.63%
3
15.00%
jun'ichi nomura
jun'ichi nomura
18
8.70%
1
5.00%
keith busch
keith busch
15
7.25%
1
5.00%
alan cox
alan cox
12
5.80%
1
5.00%
alasdair kergon
alasdair kergon
11
5.31%
2
10.00%
joe thornber
joe thornber
11
5.31%
1
5.00%
mike snitzer
mike snitzer
10
4.83%
2
10.00%
andrew morton
andrew morton
8
3.86%
1
5.00%
tejun heo
tejun heo
6
2.90%
1
5.00%
milan broz
milan broz
5
2.42%
1
5.00%
mike anderson
mike anderson
2
0.97%
1
5.00%
Total
207
100.00%
20
100.00%



void dm_destroy(struct mapped_device *md)
{
	__dm_destroy(md, true);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
kiyoshi ueda
kiyoshi ueda
17
100.00%
1
100.00%
Total
17
100.00%
1
100.00%



void dm_destroy_immediate(struct mapped_device *md)
{
	__dm_destroy(md, false);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
kiyoshi ueda
kiyoshi ueda
17
100.00%
1
100.00%
Total
17
100.00%
1
100.00%



void dm_put(struct mapped_device *md)
{
	atomic_dec(&md->holders);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
kiyoshi ueda
kiyoshi ueda
17
94.44%
1
50.00%
mike anderson
mike anderson
1
5.56%
1
50.00%
Total
18
100.00%
2
100.00%


EXPORT_SYMBOL_GPL(dm_put);



static int dm_wait_for_completion(struct mapped_device *md, int interruptible)
{
	int r = 0;
	DECLARE_WAITQUEUE(wait, current);

	add_wait_queue(&md->wait, &wait);

	while (1) {
		set_current_state(interruptible);

		if (!md_in_flight(md))
			break;

		if (interruptible == TASK_INTERRUPTIBLE &&
		    signal_pending(current)) {
			r = -EINTR;
			break;
		}

		io_schedule();
	}
	set_current_state(TASK_RUNNING);

	remove_wait_queue(&md->wait, &wait);

	return r;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
milan broz
milan broz
47
47.96%
1
16.67%
mikulas patocka
mikulas patocka
35
35.71%
2
33.33%
kiyoshi ueda
kiyoshi ueda
14
14.29%
2
33.33%
nikanth karthikesan
nikanth karthikesan
2
2.04%
1
16.67%
Total
98
100.00%
6
100.00%

/*
 * Process the deferred bios
 */


static void dm_wq_work(struct work_struct *work)
{
	struct mapped_device *md = container_of(work, struct mapped_device,
						work);
	struct bio *c;
	int srcu_idx;
	struct dm_table *map;

	map = dm_get_live_table(md, &srcu_idx);

	while (!test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) {
		spin_lock_irq(&md->deferred_lock);
		c = bio_list_pop(&md->deferred);
		spin_unlock_irq(&md->deferred_lock);

		if (!c)
			break;

		if (dm_request_based(md))
			generic_make_request(c);
		else
			__split_and_process_bio(md, map, c);
	}

	dm_put_live_table(md, srcu_idx);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mikulas patocka
mikulas patocka
85
68.00%
8
53.33%
kiyoshi ueda
kiyoshi ueda
26
20.80%
2
13.33%
milan broz
milan broz
5
4.00%
2
13.33%
alan cox
alan cox
4
3.20%
1
6.67%
alasdair kergon
alasdair kergon
4
3.20%
1
6.67%
andrew morton
andrew morton
1
0.80%
1
6.67%
Total
125
100.00%
15
100.00%



static void dm_queue_flush(struct mapped_device *md)
{
	clear_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags);
	smp_mb__after_atomic();
	queue_work(md->wq, &md->work);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
kiyoshi ueda
kiyoshi ueda
35
97.22%
1
50.00%
peter zijlstra
peter zijlstra
1
2.78%
1
50.00%
Total
36
100.00%
2
100.00%

/*
 * Swap in a new table, returning the old one for the caller to destroy.
 */


struct dm_table *dm_swap_table(struct mapped_device *md, struct dm_table *table)
{
	struct dm_table *live_map = NULL, *map = ERR_PTR(-EINVAL);
	struct queue_limits limits;
	int r;

	mutex_lock(&md->suspend_lock);

	/* device must be suspended */
	if (!dm_suspended_md(md))
		goto out;

	/*
         * If the new table has no data devices, retain the existing limits.
         * This helps multipath with queue_if_no_path if all paths disappear,
         * then new I/O is queued based on these limits, and then some paths
         * reappear.
         */
	if (dm_table_has_no_data_devices(table)) {
		live_map = dm_get_live_table_fast(md);
		if (live_map)
			limits = md->queue->limits;
		dm_put_live_table_fast(md);
	}

	if (!live_map) {
		r = dm_calculate_queue_limits(table, &limits);
		if (r) {
			map = ERR_PTR(r);
			goto out;
		}
	}

	map = __bind(md, table, &limits);

out:
	mutex_unlock(&md->suspend_lock);
	return map;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
kiyoshi ueda
kiyoshi ueda
80
52.63%
2
28.57%
mike snitzer
mike snitzer
34
22.37%
1
14.29%
alasdair kergon
alasdair kergon
26
17.11%
2
28.57%
mike christie
mike christie
9
5.92%
1
14.29%
mikulas patocka
mikulas patocka
3
1.97%
1
14.29%
Total
152
100.00%
7
100.00%

/*
 * Functions to lock and unlock any filesystem running on the
 * device.
 */


static int lock_fs(struct mapped_device *md)
{
	int r;

	WARN_ON(md->frozen_sb);

	md->frozen_sb = freeze_bdev(md->bdev);
	if (IS_ERR(md->frozen_sb)) {
		r = PTR_ERR(md->frozen_sb);
		md->frozen_sb = NULL;
		return r;
	}

	set_bit(DMF_FROZEN, &md->flags);

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
alasdair kergon
alasdair kergon
48
64.86%
6
75.00%
andrew morton
andrew morton
25
33.78%
1
12.50%
mikulas patocka
mikulas patocka
1
1.35%
1
12.50%
Total
74
100.00%
8
100.00%



static void unlock_fs(struct mapped_device *md)
{
	if (!test_bit(DMF_FROZEN, &md->flags))
		return;

	thaw_bdev(md->bdev, md->frozen_sb);
	md->frozen_sb = NULL;
	clear_bit(DMF_FROZEN, &md->flags);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
alasdair kergon
alasdair kergon
30
57.69%
4
66.67%
andrew morton
andrew morton
21
40.38%
1
16.67%
mikulas patocka
mikulas patocka
1
1.92%
1
16.67%
Total
52
100.00%
6
100.00%

/*
 * If __dm_suspend returns 0, the device is completely quiescent
 * now. There is no request-processing activity. All new requests
 * are being added to md->deferred list.
 *
 * Caller must hold md->suspend_lock
 */


static int __dm_suspend(struct mapped_device *md, struct dm_table *map,
			unsigned suspend_flags, int interruptible)
{
	bool do_lockfs = suspend_flags & DM_SUSPEND_LOCKFS_FLAG;
	bool noflush = suspend_flags & DM_SUSPEND_NOFLUSH_FLAG;
	int r;

	/*
         * DMF_NOFLUSH_SUSPENDING must be set before presuspend.
         * This flag is cleared before dm_suspend returns.
         */
	if (noflush)
		set_bit(DMF_NOFLUSH_SUSPENDING, &md->flags);

	/*
         * This gets reverted if there's an error later and the targets
         * provide the .presuspend_undo hook.
         */
	dm_table_presuspend_targets(map);

	/*
         * Flush I/O to the device.
         * Any I/O submitted after lock_fs() may not be flushed.
         * noflush takes precedence over do_lockfs.
         * (lock_fs() flushes I/Os and waits for them to complete.)
         */
	if (!noflush && do_lockfs) {
		r = lock_fs(md);
		if (r) {
			dm_table_presuspend_undo_targets(map);
			return r;
		}
	}

	/*
         * Here we must make sure that no processes are submitting requests
         * to target drivers i.e. no one may be executing
         * __split_and_process_bio. This is called from dm_request and
         * dm_wq_work.
         *
         * To get all processes out of __split_and_process_bio in dm_request,
         * we take the write lock. To prevent any process from reentering
         * __split_and_process_bio from dm_request and quiesce the thread
         * (dm_wq_work), we set BMF_BLOCK_IO_FOR_SUSPEND and call
         * flush_workqueue(md->wq).
         */
	set_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags);
	if (map)
		synchronize_srcu(&md->io_barrier);

	/*
         * Stop md->queue before flushing md->wq in case request-based
         * dm defers requests to md->wq from md->queue.
         */
	if (dm_request_based(md)) {
		dm_stop_queue(md->queue);
		if (md->kworker_task)
			flush_kthread_worker(&md->kworker);
	}

	flush_workqueue(md->wq);

	/*
         * At this point no more requests are entering target request routines.
         * We call dm_wait_for_completion to wait for all existing requests
         * to finish.
         */
	r = dm_wait_for_completion(md, interruptible);

	if (noflush)
		clear_bit(DMF_NOFLUSH_SUSPENDING, &md->flags);
	if (map)
		synchronize_srcu(&md->io_barrier);

	/* were we interrupted ? */
	if (r < 0) {
		dm_queue_flush(md);

		if (dm_request_based(md))
			dm_start_queue(md->queue);

		unlock_fs(md);
		dm_table_presuspend_undo_targets(map);
		/* pushback list is already flushed, so skip flush */
	}

	return r;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
kiyoshi ueda
kiyoshi ueda
71
30.87%
5
13.89%
mike snitzer
mike snitzer
38
16.52%
4
11.11%
alasdair kergon
alasdair kergon
35
15.22%
7
19.44%
alan cox
alan cox
17
7.39%
1
2.78%
milan broz
milan broz
14
6.09%
4
11.11%
mikulas patocka
mikulas patocka
13
5.65%
5
13.89%
jun'ichi nomura
jun'ichi nomura
10
4.35%
2
5.56%
keith busch
keith busch
10
4.35%
1
2.78%
andrew morton
andrew morton
9
3.91%
2
5.56%
hannes reinecke
hannes reinecke
8
3.48%
1
2.78%
joe thornber
joe thornber
3
1.30%
2
5.56%
tejun heo
tejun heo
2
0.87%
2
5.56%
Total
230
100.00%
36
100.00%

/*
 * We need to be able to change a mapping table under a mounted
 * filesystem.  For example we might want to move some data in
 * the background.  Before the table can be swapped with
 * dm_bind_table, dm_suspend must be called to flush any in
 * flight bios and ensure that any further io gets deferred.
 */
/*
 * Suspend mechanism in request-based dm.
 *
 * 1. Flush all I/Os by lock_fs() if needed.
 * 2. Stop dispatching any I/O by stopping the request_queue.
 * 3. Wait for all in-flight I/Os to be completed or requeued.
 *
 * To abort suspend, start the request_queue.
 */


int dm_suspend(struct mapped_device *md, unsigned suspend_flags)
{
	struct dm_table *map = NULL;
	int r = 0;

retry:
	mutex_lock_nested(&md->suspend_lock, SINGLE_DEPTH_NESTING);

	if (dm_suspended_md(md)) {
		r = -EINVAL;
		goto out_unlock;
	}

	if (dm_suspended_internally_md(md)) {
		/* already internally suspended, wait for internal resume */
		mutex_unlock(&md->suspend_lock);
		r = wait_on_bit(&md->flags, DMF_SUSPENDED_INTERNALLY, TASK_INTERRUPTIBLE);
		if (r)
			return r;
		goto retry;
	}

	map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock));

	r = __dm_suspend(md, map, suspend_flags, TASK_INTERRUPTIBLE);
	if (r)
		goto out_unlock;

	set_bit(DMF_SUSPENDED, &md->flags);

	dm_table_postsuspend_targets(map);

out_unlock:
	mutex_unlock(&md->suspend_lock);
	return r;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
73
45.34%
1
7.69%
alasdair kergon
alasdair kergon
29
18.01%
2
15.38%
alan cox
alan cox
25
15.53%
1
7.69%
andrew morton
andrew morton
11
6.83%
3
23.08%
eric dumazet
eric dumazet
9
5.59%
1
7.69%
kiyoshi ueda
kiyoshi ueda
9
5.59%
2
15.38%
joe thornber
joe thornber
3
1.86%
1
7.69%
daniel walker
daniel walker
1
0.62%
1
7.69%
milan broz
milan broz
1
0.62%
1
7.69%
Total
161
100.00%
13
100.00%



static int __dm_resume(struct mapped_device *md, struct dm_table *map)
{
	if (map) {
		int r = dm_table_resume_targets(map);
		if (r)
			return r;
	}

	dm_queue_flush(md);

	/*
         * Flushing deferred I/Os must be done after targets are resumed
         * so that mapping of targets can work correctly.
         * Request-based dm is queueing the deferred I/Os in its request_queue.
         */
	if (dm_request_based(md))
		dm_start_queue(md->queue);

	unlock_fs(md);

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
58
89.23%
2
66.67%
mikulas patocka
mikulas patocka
7
10.77%
1
33.33%
Total
65
100.00%
3
100.00%



int dm_resume(struct mapped_device *md)
{
	int r = -EINVAL;
	struct dm_table *map = NULL;

retry:
	mutex_lock_nested(&md->suspend_lock, SINGLE_DEPTH_NESTING);

	if (!dm_suspended_md(md))
		goto out;

	if (dm_suspended_internally_md(md)) {
		/* already internally suspended, wait for internal resume */
		mutex_unlock(&md->suspend_lock);
		r = wait_on_bit(&md->flags, DMF_SUSPENDED_INTERNALLY, TASK_INTERRUPTIBLE);
		if (r)
			return r;
		goto retry;
	}

	map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock));
	if (!map || !dm_table_get_size(map))
		goto out;

	r = __dm_resume(md, map);
	if (r)
		goto out;

	clear_bit(DMF_SUSPENDED, &md->flags);

	r = 0;
out:
	mutex_unlock(&md->suspend_lock);

	return r;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
153
94.44%
1
50.00%
eric dumazet
eric dumazet
9
5.56%
1
50.00%
Total
162
100.00%
2
100.00%

/*
 * Internal suspend/resume works like userspace-driven suspend. It waits
 * until all bios finish and prevents issuing new bios to the target drivers.
 * It may be used only from the kernel.
 */



static void __dm_internal_suspend(struct mapped_device *md, unsigned suspend_flags)
{
	struct dm_table *map = NULL;

	if (md->internal_suspend_count++)
		return; /* nested internal suspend */

	if (dm_suspended_md(md)) {
		set_bit(DMF_SUSPENDED_INTERNALLY, &md->flags);
		return; /* nest suspend */
	}

	map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock));

	/*
         * Using TASK_UNINTERRUPTIBLE because only NOFLUSH internal suspend is
         * supported.  Properly supporting a TASK_INTERRUPTIBLE internal suspend
         * would require changing .presuspend to return an error -- avoid this
         * until there is a need for more elaborate variants of internal suspend.
         */
	(void) __dm_suspend(md, map, suspend_flags, TASK_UNINTERRUPTIBLE);

	set_bit(DMF_SUSPENDED_INTERNALLY, &md->flags);

	dm_table_postsuspend_targets(map);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
86
87.76%
1
33.33%
eric dumazet
eric dumazet
9
9.18%
1
33.33%
mikulas patocka
mikulas patocka
3
3.06%
1
33.33%
Total
98
100.00%
3
100.00%



static void __dm_internal_resume(struct mapped_device *md)
{
	BUG_ON(!md->internal_suspend_count);

	if (--md->internal_suspend_count)
		return; /* resume from nested internal suspend */

	if (dm_suspended_md(md))
		goto done; /* resume from nested suspend */

	/*
         * NOTE: existing callers don't need to call dm_table_resume_targets
         * (which may fail -- so best to avoid it for now by passing NULL map)
         */
	(void) __dm_resume(md, NULL);

done:
	clear_bit(DMF_SUSPENDED_INTERNALLY, &md->flags);
	smp_mb__after_atomic();
	wake_up_bit(&md->flags, DMF_SUSPENDED_INTERNALLY);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
64
85.33%
1
50.00%
mikulas patocka
mikulas patocka
11
14.67%
1
50.00%
Total
75
100.00%
2
100.00%



void dm_internal_suspend_noflush(struct mapped_device *md)
{
	mutex_lock(&md->suspend_lock);
	__dm_internal_suspend(md, DM_SUSPEND_NOFLUSH_FLAG);
	mutex_unlock(&md->suspend_lock);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
33
100.00%
1
100.00%
Total
33
100.00%
1
100.00%


EXPORT_SYMBOL_GPL(dm_internal_suspend_noflush);



void dm_internal_resume(struct mapped_device *md)
{
	mutex_lock(&md->suspend_lock);
	__dm_internal_resume(md);
	mutex_unlock(&md->suspend_lock);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
mike snitzer
mike snitzer
31
100.00%
1
100.00%
Total
31
100.00%
1
100.00%


EXPORT_SYMBOL_GPL(dm_internal_resume);

/*
 * Fast variants of internal suspend/resume hold md->suspend_lock,
 * which prevents interaction with userspace-driven suspend.
 */



void dm_internal_suspend_fast(struct mapped_device *md)
{
	mutex_lock(&md->suspend_lock);
	if (dm_suspended_md(md) || dm_suspended_internally_md(md))
		return;

	set_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags);
	synchronize_srcu(&md->io_barrier);
	flush_workqueue(md->wq);
	dm_wait_for_completion(md, TASK_UNINTERRUPTIBLE);
}
Contributors
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mikulas patocka
mikulas patocka
46
73.02%
1
50.00%
mike snitzer
mike snitzer
17
26.98%
1
50.00%
Total
63
100.00%
2
100.00%


EXPORT_SYMBOL_GPL(dm_internal_suspend_fast);



void dm_internal_resume_fast(struct mapped_device *md)
{
	if (dm_suspended_md(md) || dm_suspended_internally_md(md))
		goto done;

	dm_queue_flush(md);

done:
	mutex_unlock(&md->suspend_lock);
}
Contributors
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mikulas patocka
mikulas patocka
34
85.00%
1
50.00%
mike snitzer
mike snitzer
6
15.00%
1
50.00%
Total
40
100.00%
2
100.00%


EXPORT_SYMBOL_GPL(dm_internal_resume_fast);

/*-----------------------------------------------------------------
 * Event notification.
 *---------------------------------------------------------------*/


int dm_kobject_uevent(struct mapped_device *md, enum kobject_action action,
		       unsigned cookie)
{
	char udev_cookie[DM_COOKIE_LENGTH];
	char *envp[] = { udev_cookie, NULL };

	if (!cookie)
		return kobject_uevent(&disk_to_dev(md->disk)->kobj, action);
	else {
		snprintf(udev_cookie, DM_COOKIE_LENGTH, "%s=%u",
			 DM_COOKIE_ENV_VAR_NAME, cookie);
		return kobject_uevent_env(&disk_to_dev(md->disk)->kobj,
					  action, envp);
	}
}

Contributors
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Tokens
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CommitProp
milan broz
milan broz
62
69.66%
1
25.00%
alasdair kergon
alasdair kergon
19
21.35%
1
25.00%
peter rajnoha
peter rajnoha
5
5.62%
1
25.00%
tejun heo
tejun heo
3
3.37%
1
25.00%
Total
89
100.00%
4
100.00%



uint32_t dm_next_uevent_seq(struct mapped_device *md)
{
	return atomic_add_return(1, &md->uevent_seq);
}

Contributors
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mike anderson
mike anderson
21
100.00%
1
100.00%
Total
21
100.00%
1
100.00%



uint32_t dm_get_event_nr(struct mapped_device *md)
{
	return atomic_read(&md->event_nr);
}

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andrew morton
andrew morton
19
100.00%
2
100.00%
Total
19
100.00%
2
100.00%



int dm_wait_event(struct mapped_device *md, int event_nr)
{
	return wait_event_interruptible(md->eventq,
			(event_nr != atomic_read(&md->event_nr)));
}

Contributors
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andrew morton
andrew morton
33
100.00%
2
100.00%
Total
33
100.00%
2
100.00%



void dm_uevent_add(struct mapped_device *md, struct list_head *elist)
{
	unsigned long flags;

	spin_lock_irqsave(&md->uevent_lock, flags);
	list_add(elist, &md->uevent_list);
	spin_unlock_irqrestore(&md->uevent_lock, flags);
}

Contributors
Person
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mike anderson
mike anderson
49
100.00%
1
100.00%
Total
49
100.00%
1
100.00%

/*
 * The gendisk is only valid as long as you have a reference
 * count on 'md'.
 */


struct gendisk *dm_disk(struct mapped_device *md)
{
	return md->disk;
}
Contributors
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alan cox
alan cox
11
64.71%
1
50.00%
al viro
al viro
6
35.29%
1
50.00%
Total
17
100.00%
2
100.00%


EXPORT_SYMBOL_GPL(dm_disk);



struct kobject *dm_kobject(struct mapped_device *md)
{
	return &md->kobj_holder.kobj;
}

Contributors
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milan broz
milan broz
18
90.00%
1
50.00%
mikulas patocka
mikulas patocka
2
10.00%
1
50.00%
Total
20
100.00%
2
100.00%



struct mapped_device *dm_get_from_kobject(struct kobject *kobj)
{
	struct mapped_device *md;

	md = container_of(kobj, struct mapped_device, kobj_holder.kobj);

	if (test_bit(DMF_FREEING, &md->flags) ||
	    dm_deleting_md(md))
		return NULL;

	dm_get(md);
	return md;
}

Contributors
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CommitProp
milan broz
milan broz
56
94.92%
2
50.00%
mikulas patocka
mikulas patocka
2
3.39%
1
25.00%
mike anderson
mike anderson
1
1.69%
1
25.00%
Total
59
100.00%
4
100.00%



int dm_suspended_md(struct mapped_device *md)
{
	return test_bit(DMF_SUSPENDED, &md->flags);
}

Contributors
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alan cox
alan cox
15
71.43%
1
33.33%
mike snitzer
mike snitzer
5
23.81%
1
33.33%
kiyoshi ueda
kiyoshi ueda
1
4.76%
1
33.33%
Total
21
100.00%
3
100.00%



int dm_suspended_internally_md(struct mapped_device *md)
{
	return test_bit(DMF_SUSPENDED_INTERNALLY, &md->flags);
}

Contributors
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CommitProp
mike snitzer
mike snitzer
16
76.19%
1
50.00%
alan cox
alan cox
5
23.81%
1
50.00%
Total
21
100.00%
2
100.00%



int dm_test_deferred_remove_flag(struct mapped_device *md)
{
	return test_bit(DMF_DEFERRED_REMOVE, &md->flags);
}

Contributors
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mikulas patocka
mikulas patocka
21
100.00%
1
100.00%
Total
21
100.00%
1
100.00%



int dm_suspended(struct dm_target *ti)
{
	return dm_suspended_md(dm_table_get_md(ti->table));
}
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kiyoshi ueda
kiyoshi ueda
21
100.00%
2
100.00%
Total
21
100.00%
2
100.00%


EXPORT_SYMBOL_GPL(dm_suspended);



int dm_noflush_suspending(struct dm_target *ti)
{
	return __noflush_suspending(dm_table_get_md(ti->table));
}
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kiyoshi ueda
kiyoshi ueda
21
100.00%
2
100.00%
Total
21
100.00%
2
100.00%


EXPORT_SYMBOL_GPL(dm_noflush_suspending);



struct dm_md_mempools *dm_alloc_md_mempools(struct mapped_device *md, unsigned type,
					    unsigned integrity, unsigned per_io_data_size)
{
	struct dm_md_mempools *pools = kzalloc_node(sizeof(*pools), GFP_KERNEL, md->numa_node_id);
	struct kmem_cache *cachep = NULL;
	unsigned int pool_size = 0;
	unsigned int front_pad;

	if (!pools)
		return NULL;

	type = filter_md_type(type, md);

	switch (type) {
	case DM_TYPE_BIO_BASED:
		cachep = _io_cache;
		pool_size = dm_get_reserved_bio_based_ios();
		front_pad = roundup(per_io_data_size, __alignof__(struct dm_target_io)) + offsetof(struct dm_target_io, clone);
		break;
	case DM_TYPE_REQUEST_BASED:
		cachep = _rq_tio_cache;
		pool_size = dm_get_reserved_rq_based_ios();
		pools->rq_pool = mempool_create_slab_pool(pool_size, _rq_cache);
		if (!pools->rq_pool)
			goto out;
		/* fall through to setup remaining rq-based pools */
	case DM_TYPE_MQ_REQUEST_BASED:
		if (!pool_size)
			pool_size = dm_get_reserved_rq_based_ios();
		front_pad = offsetof(struct dm_rq_clone_bio_info, clone);
		/* per_io_data_size is used for blk-mq pdu at queue allocation */
		break;
	default:
		BUG();
	}

	if (cachep) {
		pools->io_pool = mempool_create_slab_pool(pool_size, cachep);
		if (!pools->io_pool)
			goto out;
	}

	pools->bs = bioset_create_nobvec(pool_size, front_pad);
	if (!pools->bs)
		goto out;

	if (integrity && bioset_integrity_create(pools->bs, pool_size))
		goto out;

	return pools;

out:
	dm_free_md_mempools(pools);

	return NULL;
}

Contributors
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CommitProp
mike snitzer
mike snitzer
145
56.86%
10
55.56%
kiyoshi ueda
kiyoshi ueda
60
23.53%
1
5.56%
jun'ichi nomura
jun'ichi nomura
23
9.02%
2
11.11%
mikulas patocka
mikulas patocka
16
6.27%
2
11.11%
martin k. petersen
martin k. petersen
5
1.96%
1
5.56%
kent overstreet
kent overstreet
4
1.57%
1
5.56%
christoph hellwig
christoph hellwig
2
0.78%
1
5.56%
Total
255
100.00%
18
100.00%



void dm_free_md_mempools(struct dm_md_mempools *pools)
{
	if (!pools)
		return;

	mempool_destroy(pools->io_pool);
	mempool_destroy(pools->rq_pool);

	if (pools->bs)
		bioset_free(pools->bs);

	kfree(pools);
}

Contributors
Person
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CommitProp
kiyoshi ueda
kiyoshi ueda
37
77.08%
1
50.00%
mike snitzer
mike snitzer
11
22.92%
1
50.00%
Total
48
100.00%
2
100.00%



static int dm_pr_register(struct block_device *bdev, u64 old_key, u64 new_key,
			  u32 flags)
{
	struct mapped_device *md = bdev->bd_disk->private_data;
	const struct pr_ops *ops;
	fmode_t mode;
	int r;

	r = dm_grab_bdev_for_ioctl(md, &bdev, &mode);
	if (r < 0)
		return r;

	ops = bdev->bd_disk->fops->pr_ops;
	if (ops && ops->pr_register)
		r = ops->pr_register(bdev, old_key, new_key, flags);
	else
		r = -EOPNOTSUPP;

	bdput(bdev);
	return r;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
christoph hellwig
christoph hellwig
101
90.18%
1
16.67%
alan cox
alan cox
5
4.46%
1
16.67%
mike snitzer
mike snitzer
3
2.68%
1
16.67%
andrew morton
andrew morton
1
0.89%
1
16.67%
darrick j. wong
darrick j. wong
1
0.89%
1
16.67%
milan broz
milan broz
1
0.89%
1
16.67%
Total
112
100.00%
6
100.00%



static int dm_pr_reserve(struct block_device *bdev, u64 key, enum pr_type type,
			 u32 flags)
{
	struct mapped_device *md = bdev->bd_disk->private_data;
	const struct pr_ops *ops;
	fmode_t mode;
	int r;

	r = dm_grab_bdev_for_ioctl(md, &bdev, &mode);
	if (r < 0)
		return r;

	ops = bdev->bd_disk->fops->pr_ops;
	if (ops && ops->pr_reserve)
		r = ops->pr_reserve(bdev, key, type, flags);
	else
		r = -EOPNOTSUPP;

	bdput(bdev);
	return r;
}

Contributors
Person
Tokens
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Commits
CommitProp
christoph hellwig
christoph hellwig
105
92.92%
1
20.00%
mike snitzer
mike snitzer
3
2.65%
1
20.00%
alan cox
alan cox
3
2.65%
1
20.00%
darrick j. wong
darrick j. wong
1
0.88%
1
20.00%
milan broz
milan broz
1
0.88%
1
20.00%
Total
113
100.00%
5
100.00%



static int dm_pr_release(struct block_device *bdev, u64 key, enum pr_type type)
{
	struct mapped_device *md = bdev->bd_disk->private_data;
	const struct pr_ops *ops;
	fmode_t mode;
	int r;

	r = dm_grab_bdev_for_ioctl(md, &bdev, &mode);
	if (r < 0)
		return r;

	ops = bdev->bd_disk->fops->pr_ops;
	if (ops && ops->pr_release)
		r = ops->pr_release(bdev, key, type);
	else
		r = -EOPNOTSUPP;

	bdput(bdev);
	return r;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
christoph hellwig
christoph hellwig
105
97.22%
1
50.00%
mike snitzer
mike snitzer
3
2.78%
1
50.00%
Total
108
100.00%
2
100.00%



static int dm_pr_preempt(struct block_device *bdev, u64 old_key, u64 new_key,
			 enum pr_type type, bool abort)
{
	struct mapped_device *md = bdev->bd_disk->private_data;
	const struct pr_ops *ops;
	fmode_t mode;
	int r;

	r = dm_grab_bdev_for_ioctl(md, &bdev, &mode);
	if (r < 0)
		return r;

	ops = bdev->bd_disk->fops->pr_ops;
	if (ops && ops->pr_preempt)
		r = ops->pr_preempt(bdev, old_key, new_key, type, abort);
	else
		r = -EOPNOTSUPP;

	bdput(bdev);
	return r;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
christoph hellwig
christoph hellwig
115
97.46%
1
50.00%
mike snitzer
mike snitzer
3
2.54%
1
50.00%
Total
118
100.00%
2
100.00%



static int dm_pr_clear(struct block_device *bdev, u64 key)
{
	struct mapped_device *md = bdev->bd_disk->private_data;
	const struct pr_ops *ops;
	fmode_t mode;
	int r;

	r = dm_grab_bdev_for_ioctl(md, &bdev, &mode);
	if (r < 0)
		return r;

	ops = bdev->bd_disk->fops->pr_ops;
	if (ops && ops->pr_clear)
		r = ops->pr_clear(bdev, key);
	else
		r = -EOPNOTSUPP;

	bdput(bdev);
	return r;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
christoph hellwig
christoph hellwig
99
97.06%
1
50.00%
mike snitzer
mike snitzer
3
2.94%
1
50.00%
Total
102
100.00%
2
100.00%


static const struct pr_ops dm_pr_ops = {
	.pr_register	= dm_pr_register,
	.pr_reserve	= dm_pr_reserve,
	.pr_release	= dm_pr_release,
	.pr_preempt	= dm_pr_preempt,
	.pr_clear	= dm_pr_clear,
};


static const struct block_device_operations dm_blk_dops = {
	.open = dm_blk_open,
	.release = dm_blk_close,
	.ioctl = dm_blk_ioctl,
	.getgeo = dm_blk_getgeo,
	.pr_ops = &dm_pr_ops,
	.owner = THIS_MODULE
};

/*
 * module hooks
 */

module_init(dm_init);

module_exit(dm_exit);

module_param(major, uint, 0);
MODULE_PARM_DESC(major, "The major number of the device mapper");

module_param(reserved_bio_based_ios, uint, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(reserved_bio_based_ios, "Reserved IOs in bio-based mempools");

module_param(reserved_rq_based_ios, uint, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(reserved_rq_based_ios, "Reserved IOs in request-based mempools");

module_param(use_blk_mq, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(use_blk_mq, "Use block multiqueue for request-based DM devices");

module_param(dm_mq_nr_hw_queues, uint, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(dm_mq_nr_hw_queues, "Number of hardware queues for request-based dm-mq devices");

module_param(dm_mq_queue_depth, uint, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(dm_mq_queue_depth, "Queue depth for request-based dm-mq devices");

module_param(dm_numa_node, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(dm_numa_node, "NUMA node for DM device memory allocations");

MODULE_DESCRIPTION(DM_NAME " driver");
MODULE_AUTHOR("Joe Thornber <dm-devel@redhat.com>");
MODULE_LICENSE("GPL");
Overall Contributors
Person
Tokens
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Commits
CommitProp
mike snitzer
mike snitzer
4929
32.77%
61
19.74%
kiyoshi ueda
kiyoshi ueda
2453
16.31%
25
8.09%
mikulas patocka
mikulas patocka
1486
9.88%
46
14.89%
alan cox
alan cox
1025
6.81%
2
0.65%
alasdair kergon
alasdair kergon
834
5.54%
35
11.33%
benjamin marzinski
benjamin marzinski
755
5.02%
1
0.32%
christoph hellwig
christoph hellwig
744
4.95%
5
1.62%
andrew morton
andrew morton
442
2.94%
16
5.18%
milan broz
milan broz
434
2.89%
14
4.53%
jun'ichi nomura
jun'ichi nomura
247
1.64%
16
5.18%
jeff mahoney
jeff mahoney
211
1.40%
6
1.94%
mike anderson
mike anderson
210
1.40%
5
1.62%
keith busch
keith busch
197
1.31%
2
0.65%
tejun heo
tejun heo
184
1.22%
11
3.56%
darrick j. wong
darrick j. wong
162
1.08%
1
0.32%
kent overstreet
kent overstreet
132
0.88%
4
1.29%
joe thornber
joe thornber
105
0.70%
10
3.24%
nikanth karthikesan
nikanth karthikesan
56
0.37%
1
0.32%
andries brouwer
andries brouwer
49
0.33%
2
0.65%
kevin corry
kevin corry
47
0.31%
2
0.65%
eric dumazet
eric dumazet
39
0.26%
1
0.32%
hannes reinecke
hannes reinecke
36
0.24%
2
0.65%
jens axboe
jens axboe
35
0.23%
5
1.62%
martin k. petersen
martin k. petersen
31
0.21%
3
0.97%
stefan bader
stefan bader
23
0.15%
1
0.32%
david teigland
david teigland
21
0.14%
2
0.65%
al viro
al viro
21
0.14%
3
0.97%
li shaohua
li shaohua
21
0.14%
1
0.32%
namhyung kim
namhyung kim
20
0.13%
1
0.32%
linus torvalds
linus torvalds
11
0.07%
1
0.32%
mike christie
mike christie
9
0.06%
1
0.32%
arnd bergmann
arnd bergmann
8
0.05%
2
0.65%
gu zheng
gu zheng
8
0.05%
1
0.32%
peter osterlund
peter osterlund
5
0.03%
1
0.32%
peter rajnoha
peter rajnoha
5
0.03%
1
0.32%
edward goggin
edward goggin
5
0.03%
1
0.32%
chandra seetharaman
chandra seetharaman
5
0.03%
1
0.32%
sami tolvanen
sami tolvanen
5
0.03%
1
0.32%
pranith kumar
pranith kumar
5
0.03%
2
0.65%
bryn m. reeves
bryn m. reeves
4
0.03%
1
0.32%
arjan van de ven
arjan van de ven
3
0.02%
1
0.32%
daniel walker
daniel walker
3
0.02%
1
0.32%
bob liu
bob liu
3
0.02%
1
0.32%
richard kennedy
richard kennedy
3
0.02%
1
0.32%
christoph lameter
christoph lameter
2
0.01%
1
0.32%
neil brown
neil brown
2
0.01%
1
0.32%
monam agarwal
monam agarwal
1
0.01%
1
0.32%
ishai rabinovitz
ishai rabinovitz
1
0.01%
1
0.32%
peter zijlstra
peter zijlstra
1
0.01%
1
0.32%
li zefan
li zefan
1
0.01%
1
0.32%
alexey dobriyan
alexey dobriyan
1
0.01%
1
0.32%
alex chen
alex chen
1
0.01%
1
0.32%
Total
15041
100.00%
309
100.00%
  
Directory: drivers/md

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