Commit 97519dc5 authored by Rafał Miłecki's avatar Rafał Miłecki Committed by Brian Norris
Browse files

mtd: partitions: add support for subpartitions 



Some flash device partitions can be containers with extra subpartitions
(volumes). All callbacks are already capable of this additional level of
indirection.

This patch makes sure we always display subpartitions using a tree
structure and takes care of deleting subpartitions when parent gets
removed.

Signed-off-by: default avatarRafał Miłecki <rafal@milecki.pl>
Signed-off-by: default avatarBrian Norris <computersforpeace@gmail.com>
parent 0a9d72b6

drivers/mtd/mtdpart.c

+16 −7
Original line number Original line Diff line number Diff line
@@ -413,7 +413,7 @@ static struct mtd_part *allocate_partition(struct mtd_info *parent, 
	 * parent conditional on that option. Note, this is a way to

	 * parent conditional on that option. Note, this is a way to

	 * distinguish between the master and the partition in sysfs.

	 * distinguish between the master and the partition in sysfs.

	 */

	 */

	slave->mtd.dev.parent = IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER) ?

	slave->mtd.dev.parent = IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER) || mtd_is_partition(parent) ?

				&parent->dev :

				&parent->dev :

				parent->dev.parent;

				parent->dev.parent;

	slave->mtd.dev.of_node = part->of_node;

	slave->mtd.dev.of_node = part->of_node;
@@ -664,8 +664,17 @@ EXPORT_SYMBOL_GPL(mtd_add_partition); 
 */

 */

static int __mtd_del_partition(struct mtd_part *priv)

static int __mtd_del_partition(struct mtd_part *priv)

{

{

	struct mtd_part *child, *next;

	int err;

	int err;





	list_for_each_entry_safe(child, next, &mtd_partitions, list) {

		if (child->parent == &priv->mtd) {

			err = __mtd_del_partition(child);

			if (err)

				return err;

		}

	}



	sysfs_remove_files(&priv->mtd.dev.kobj, mtd_partition_attrs);

	sysfs_remove_files(&priv->mtd.dev.kobj, mtd_partition_attrs);





	err = del_mtd_device(&priv->mtd);

	err = del_mtd_device(&priv->mtd);
@@ -680,16 +689,16 @@ static int __mtd_del_partition(struct mtd_part *priv) 




/*

/*

 * This function unregisters and destroy all slave MTD objects which are

 * This function unregisters and destroy all slave MTD objects which are

 * attached to the given master MTD object.

 * attached to the given MTD object.

 */

 */

int del_mtd_partitions(struct mtd_info *master)

int del_mtd_partitions(struct mtd_info *mtd)

{

{

	struct mtd_part *slave, *next;

	struct mtd_part *slave, *next;

	int ret, err = 0;

	int ret, err = 0;





	mutex_lock(&mtd_partitions_mutex);

	mutex_lock(&mtd_partitions_mutex);

	list_for_each_entry_safe(slave, next, &mtd_partitions, list)

	list_for_each_entry_safe(slave, next, &mtd_partitions, list)

		if (slave->parent == master) {

		if (slave->parent == mtd) {

			ret = __mtd_del_partition(slave);

			ret = __mtd_del_partition(slave);

			if (ret < 0)

			if (ret < 0)

				err = ret;

				err = ret;
@@ -699,14 +708,14 @@ int del_mtd_partitions(struct mtd_info *master) 
	return err;

	return err;

}

}





int mtd_del_partition(struct mtd_info *master, int partno)

int mtd_del_partition(struct mtd_info *mtd, int partno)

{

{

	struct mtd_part *slave, *next;

	struct mtd_part *slave, *next;

	int ret = -EINVAL;

	int ret = -EINVAL;





	mutex_lock(&mtd_partitions_mutex);

	mutex_lock(&mtd_partitions_mutex);

	list_for_each_entry_safe(slave, next, &mtd_partitions, list)

	list_for_each_entry_safe(slave, next, &mtd_partitions, list)

		if ((slave->parent == master) &&

		if ((slave->parent == mtd) &&

		    (slave->mtd.index == partno)) {

		    (slave->mtd.index == partno)) {

			ret = __mtd_del_partition(slave);

			ret = __mtd_del_partition(slave);

			break;

			break;
@@ -939,6 +948,6 @@ uint64_t mtd_get_device_size(const struct mtd_info *mtd) 
	if (!mtd_is_partition(mtd))

	if (!mtd_is_partition(mtd))

		return mtd->size;

		return mtd->size;





	return mtd_to_part(mtd)->parent->size;

	return mtd_get_device_size(mtd_to_part(mtd)->parent);

}

}

EXPORT_SYMBOL_GPL(mtd_get_device_size);
 
EXPORT_SYMBOL_GPL(mtd_get_device_size);