Commit b84b0287 authored by Alasdair G Kergon's avatar Alasdair G Kergon Committed by Linus Torvalds
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[PATCH] device-mapper: tidy dm_suspend 



Tidy dm_suspend.

Signed-Off-By: default avatarAlasdair G Kergon <agk@redhat.com>
From: Christoph Hellwig <hch@lst.de>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 354e0071

drivers/md/dm.c

+23 −20
Original line number Diff line number Diff line
@@ -1048,20 +1048,16 @@ int dm_suspend(struct mapped_device *md) 
{

	struct dm_table *map;

	DECLARE_WAITQUEUE(wait, current);

	int error;

	int error = -EINVAL;



	/* Flush I/O to the device. */

	down_read(&md->lock);

	if (test_bit(DMF_BLOCK_IO, &md->flags)) {

		up_read(&md->lock);

		return -EINVAL;

	}

	if (test_bit(DMF_BLOCK_IO, &md->flags))

		goto out_read_unlock;



	error = __lock_fs(md);

	if (error) {

		up_read(&md->lock);

		return error;

	}

	if (error)

		goto out_read_unlock;



	map = dm_get_table(md);

	if (map)
@@ -1075,15 +1071,14 @@ int dm_suspend(struct mapped_device *md) 
	 * If the flag is already set we know another thread is trying to

	 * suspend as well, so we leave the fs locked for this thread.

	 */

	error = -EINVAL;

	down_write(&md->lock);

	if (test_bit(DMF_BLOCK_IO, &md->flags)) {

		up_write(&md->lock);

	if (test_and_set_bit(DMF_BLOCK_IO, &md->flags)) {

		if (map)

			dm_table_put(map);

		return -EINVAL;

		goto out_write_unlock;

	}



	set_bit(DMF_BLOCK_IO, &md->flags);

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

	up_write(&md->lock);
@@ -1111,13 +1106,9 @@ int dm_suspend(struct mapped_device *md) 
	remove_wait_queue(&md->wait, &wait);



	/* were we interrupted ? */

	if (atomic_read(&md->pending)) {

		/* FIXME Undo the presuspend_targets */

		__unlock_fs(md);

		clear_bit(DMF_BLOCK_IO, &md->flags);

		up_write(&md->lock);

		return -EINTR;

	}

	error = -EINTR;

	if (atomic_read(&md->pending))

		goto out_unfreeze;



	set_bit(DMF_SUSPENDED, &md->flags);
@@ -1128,6 +1119,18 @@ int dm_suspend(struct mapped_device *md) 
	up_write(&md->lock);



	return 0;



out_unfreeze:

	/* FIXME Undo dm_table_presuspend_targets */

	__unlock_fs(md);

	clear_bit(DMF_BLOCK_IO, &md->flags);

out_write_unlock:

	up_write(&md->lock);

	return error;



out_read_unlock:

	up_read(&md->lock);

	return error;

}



int dm_resume(struct mapped_device *md)