Commit b9d9c82b authored by Kay Sievers's avatar Kay Sievers Committed by Greg Kroah-Hartman
Browse files

[PATCH] Driver core: add generic "subsystem" link to all devices 



Like the SUBSYTEM= key we find in the environment of the uevent, this
creates a generic "subsystem" link in sysfs for every device. Userspace
usually doesn't care at all if its a "class" or a "bus" device. This
provides an unified way to determine the subsytem of a device, regardless
of the way the driver core has created it.

Signed-off-by: default avatarKay Sievers <kay.sievers@suse.de>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 23681e47

block/genhd.c

+2 −5
Original line number Diff line number Diff line
@@ -17,8 +17,7 @@ 
#include <linux/buffer_head.h>

#include <linux/mutex.h>



static struct subsystem block_subsys;



struct subsystem block_subsys;

static DEFINE_MUTEX(block_subsys_lock);



/*
@@ -511,9 +510,7 @@ static struct kset_uevent_ops block_uevent_ops = { 
	.uevent		= block_uevent,

};



/* declare block_subsys. */

static decl_subsys(block, &ktype_block, &block_uevent_ops);



decl_subsys(block, &ktype_block, &block_uevent_ops);



/*

 * aggregate disk stat collector.  Uses the same stats that the sysfs

drivers/base/bus.c

+2 −0
Original line number Diff line number Diff line
@@ -374,6 +374,7 @@ int bus_add_device(struct device * dev) 
		error = device_add_attrs(bus, dev);

		if (!error) {

			sysfs_create_link(&bus->devices.kobj, &dev->kobj, dev->bus_id);

			sysfs_create_link(&dev->kobj, &dev->bus->subsys.kset.kobj, "subsystem");

			sysfs_create_link(&dev->kobj, &dev->bus->subsys.kset.kobj, "bus");

		}

	}
@@ -408,6 +409,7 @@ void bus_attach_device(struct device * dev) 
void bus_remove_device(struct device * dev)

{

	if (dev->bus) {

		sysfs_remove_link(&dev->kobj, "subsystem");

		sysfs_remove_link(&dev->kobj, "bus");

		sysfs_remove_link(&dev->bus->devices.kobj, dev->bus_id);

		device_remove_attrs(dev->bus, dev);

drivers/base/class.c

+2 −0
Original line number Diff line number Diff line
@@ -561,6 +561,7 @@ int class_device_add(struct class_device *class_dev) 
		goto out2;



	/* add the needed attributes to this device */

	sysfs_create_link(&class_dev->kobj, &parent_class->subsys.kset.kobj, "subsystem");

	class_dev->uevent_attr.attr.name = "uevent";

	class_dev->uevent_attr.attr.mode = S_IWUSR;

	class_dev->uevent_attr.attr.owner = parent_class->owner;
@@ -737,6 +738,7 @@ void class_device_del(struct class_device *class_dev) 
		sysfs_remove_link(&class_dev->kobj, "device");

		sysfs_remove_link(&class_dev->dev->kobj, class_name);

	}

	sysfs_remove_link(&class_dev->kobj, "subsystem");

	class_device_remove_file(class_dev, &class_dev->uevent_attr);

	if (class_dev->devt_attr)

		class_device_remove_file(class_dev, class_dev->devt_attr);

drivers/base/core.c

+7 −2
Original line number Diff line number Diff line
@@ -319,9 +319,12 @@ int device_add(struct device *dev) 
		dev->devt_attr = attr;

	}



	if (dev->class)

	if (dev->class) {

		sysfs_create_link(&dev->kobj, &dev->class->subsys.kset.kobj,

				  "subsystem");

		sysfs_create_link(&dev->class->subsys.kset.kobj, &dev->kobj,

				  dev->bus_id);

	}



	if ((error = device_pm_add(dev)))

		goto PMError;
@@ -422,8 +425,10 @@ void device_del(struct device * dev) 
		klist_del(&dev->knode_parent);

	if (dev->devt_attr)

		device_remove_file(dev, dev->devt_attr);

	if (dev->class)

	if (dev->class) {

		sysfs_remove_link(&dev->kobj, "subsystem");

		sysfs_remove_link(&dev->class->subsys.kset.kobj, dev->bus_id);

	}

	device_remove_file(dev, &dev->uevent_attr);



	/* Notify the platform of the removal, in case they

fs/partitions/check.c

+4 −0
Original line number Diff line number Diff line
@@ -329,6 +329,7 @@ void delete_partition(struct gendisk *disk, int part) 
	p->ios[0] = p->ios[1] = 0;

	p->sectors[0] = p->sectors[1] = 0;

	devfs_remove("%s/part%d", disk->devfs_name, part);

	sysfs_remove_link(&p->kobj, "subsystem");

	if (p->holder_dir)

		kobject_unregister(p->holder_dir);

	kobject_uevent(&p->kobj, KOBJ_REMOVE);
@@ -363,6 +364,7 @@ void add_partition(struct gendisk *disk, int part, sector_t start, sector_t len) 
	kobject_add(&p->kobj);

	if (!disk->part_uevent_suppress)

		kobject_uevent(&p->kobj, KOBJ_ADD);

	sysfs_create_link(&p->kobj, &block_subsys.kset.kobj, "subsystem");

	partition_sysfs_add_subdir(p);

	disk->part[part-1] = p;

}
@@ -398,6 +400,7 @@ static void disk_sysfs_symlinks(struct gendisk *disk) 
			kfree(disk_name);

		}

	}

	sysfs_create_link(&disk->kobj, &block_subsys.kset.kobj, "subsystem");

}



/* Not exported, helper to add_disk(). */
@@ -548,5 +551,6 @@ void del_gendisk(struct gendisk *disk) 
		put_device(disk->driverfs_dev);

		disk->driverfs_dev = NULL;

	}

	sysfs_remove_link(&disk->kobj, "subsystem");

	kobject_del(&disk->kobj);

}

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