Commit 23e6e57a authored by Mikulas Patocka's avatar Mikulas Patocka
Browse files

dm: make "dmsetup remove_all" interruptible 



The command "dmsetup remove_all" may take a long time (a minute for
removing 1000 devices), so make it interruptible with fatal signals.

For better readability, the bool arguments were changed to flags.

Signed-off-by: default avatarMikulas Patocka <mpatocka@redhat.com>
Reviewed-by: default avatarBart Van Assche <bvanassche@acm.org>
parent b7cce3e2

drivers/md/dm-ioctl.c

+25 −10
Original line number Diff line number Diff line
@@ -64,7 +64,11 @@ struct vers_iter { 
static struct rb_root name_rb_tree = RB_ROOT;

static struct rb_root uuid_rb_tree = RB_ROOT;



static void dm_hash_remove_all(bool keep_open_devices, bool mark_deferred, bool only_deferred);

#define DM_REMOVE_KEEP_OPEN_DEVICES	1

#define DM_REMOVE_MARK_DEFERRED		2

#define DM_REMOVE_ONLY_DEFERRED		4

#define DM_REMOVE_INTERRUPTIBLE		8

static int dm_hash_remove_all(unsigned flags);



/*

 * Guards access to both hash tables.
@@ -78,7 +82,7 @@ static DEFINE_MUTEX(dm_hash_cells_mutex); 


static void dm_hash_exit(void)

{

	dm_hash_remove_all(false, false, false);

	dm_hash_remove_all(0);

}



/*
@@ -333,7 +337,7 @@ static struct dm_table *__hash_remove(struct hash_cell *hc) 
	return table;

}



static void dm_hash_remove_all(bool keep_open_devices, bool mark_deferred, bool only_deferred)

static int dm_hash_remove_all(unsigned flags)

{

	int dev_skipped;

	struct rb_node *n;
@@ -347,12 +351,17 @@ static void dm_hash_remove_all(bool keep_open_devices, bool mark_deferred, bool 
	down_write(&_hash_lock);



	for (n = rb_first(&name_rb_tree); n; n = rb_next(n)) {

		if (flags & DM_REMOVE_INTERRUPTIBLE && fatal_signal_pending(current)) {

			up_write(&_hash_lock);

			return -EINTR;

		}



		hc = container_of(n, struct hash_cell, name_node);

		md = hc->md;

		dm_get(md);



		if (keep_open_devices &&

		    dm_lock_for_deletion(md, mark_deferred, only_deferred)) {

		if (flags & DM_REMOVE_KEEP_OPEN_DEVICES &&

		    dm_lock_for_deletion(md, !!(flags & DM_REMOVE_MARK_DEFERRED), !!(flags & DM_REMOVE_ONLY_DEFERRED))) {

			dm_put(md);

			dev_skipped++;

			continue;
@@ -368,7 +377,7 @@ static void dm_hash_remove_all(bool keep_open_devices, bool mark_deferred, bool 
		}

		dm_ima_measure_on_device_remove(md, true);

		dm_put(md);

		if (likely(keep_open_devices))

		if (likely(flags & DM_REMOVE_KEEP_OPEN_DEVICES))

			dm_destroy(md);

		else

			dm_destroy_immediate(md);
@@ -384,8 +393,10 @@ static void dm_hash_remove_all(bool keep_open_devices, bool mark_deferred, bool 


	up_write(&_hash_lock);



	if (dev_skipped && !only_deferred)

	if (dev_skipped && !(flags & DM_REMOVE_ONLY_DEFERRED))

		DMWARN("remove_all left %d open device(s)", dev_skipped);



	return 0;

}



/*
@@ -513,7 +524,7 @@ static struct mapped_device *dm_hash_rename(struct dm_ioctl *param, 


void dm_deferred_remove(void)

{

	dm_hash_remove_all(true, false, true);

	dm_hash_remove_all(DM_REMOVE_KEEP_OPEN_DEVICES | DM_REMOVE_ONLY_DEFERRED);

}



/*
@@ -529,9 +540,13 @@ typedef int (*ioctl_fn)(struct file *filp, struct dm_ioctl *param, size_t param_ 


static int remove_all(struct file *filp, struct dm_ioctl *param, size_t param_size)

{

	dm_hash_remove_all(true, !!(param->flags & DM_DEFERRED_REMOVE), false);

	int r;

	int flags = DM_REMOVE_KEEP_OPEN_DEVICES | DM_REMOVE_INTERRUPTIBLE;

	if (param->flags & DM_DEFERRED_REMOVE)

		flags |= DM_REMOVE_MARK_DEFERRED;

	r = dm_hash_remove_all(flags);

	param->data_size = 0;

	return 0;

	return r;

}



/*