Commit fa675765 authored by Greg Kroah-Hartman's avatar Greg Kroah-Hartman
Browse files

Revert mount/umount uevent removal 



This change reverts the 033b96fd commit
from Kay Sievers that removed the mount/umount uevents from the kernel.
Some older versions of HAL still depend on these events to detect when a
new device has been mounted.  These events are not correctly emitted,
and are broken by design, and so, should not be relied upon by any
future program.  Instead, the /proc/mounts file should be polled to
properly detect this kind of event.

A feature-removal-schedule.txt entry has been added, noting when this
interface will be removed from the kernel.

Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent b00dc3ad

Documentation/feature-removal-schedule.txt

+9 −0
Original line number Diff line number Diff line
@@ -171,3 +171,12 @@ Why: The ISA interface is faster and should be always available. The I2C 
	probing is also known to cause trouble in at least one case (see

	bug #5889.)

Who:	Jean Delvare <khali@linux-fr.org>



---------------------------



What:	mount/umount uevents

When:	February 2007

Why:	These events are not correct, and do not properly let userspace know

	when a file system has been mounted or unmounted.  Userspace should

	poll the /proc/mounts file instead to detect this properly.

Who:	Greg Kroah-Hartman <gregkh@suse.de>

fs/super.c

+14 −1
Original line number Diff line number Diff line
@@ -666,6 +666,16 @@ static int test_bdev_super(struct super_block *s, void *data) 
	return (void *)s->s_bdev == data;

}



static void bdev_uevent(struct block_device *bdev, enum kobject_action action)

{

	if (bdev->bd_disk) {

		if (bdev->bd_part)

			kobject_uevent(&bdev->bd_part->kobj, action);

		else

			kobject_uevent(&bdev->bd_disk->kobj, action);

	}

}



struct super_block *get_sb_bdev(struct file_system_type *fs_type,

	int flags, const char *dev_name, void *data,

	int (*fill_super)(struct super_block *, void *, int))
@@ -707,8 +717,10 @@ struct super_block *get_sb_bdev(struct file_system_type *fs_type, 
			up_write(&s->s_umount);

			deactivate_super(s);

			s = ERR_PTR(error);

		} else

		} else {

			s->s_flags |= MS_ACTIVE;

			bdev_uevent(bdev, KOBJ_MOUNT);

		}

	}



	return s;
@@ -724,6 +736,7 @@ void kill_block_super(struct super_block *sb) 
{

	struct block_device *bdev = sb->s_bdev;



	bdev_uevent(bdev, KOBJ_UMOUNT);

	generic_shutdown_super(sb);

	sync_blockdev(bdev);

	close_bdev_excl(bdev);

include/linux/kobject.h

+4 −2
Original line number Diff line number Diff line
@@ -41,8 +41,10 @@ enum kobject_action { 
	KOBJ_ADD	= (__force kobject_action_t) 0x01,	/* exclusive to core */

	KOBJ_REMOVE	= (__force kobject_action_t) 0x02,	/* exclusive to core */

	KOBJ_CHANGE	= (__force kobject_action_t) 0x03,	/* device state change */

	KOBJ_OFFLINE	= (__force kobject_action_t) 0x04,	/* device offline */

	KOBJ_ONLINE	= (__force kobject_action_t) 0x05,	/* device online */

	KOBJ_MOUNT	= (__force kobject_action_t) 0x04,	/* mount event for block devices (broken) */

	KOBJ_UMOUNT	= (__force kobject_action_t) 0x05,	/* umount event for block devices (broken) */

	KOBJ_OFFLINE	= (__force kobject_action_t) 0x06,	/* device offline */

	KOBJ_ONLINE	= (__force kobject_action_t) 0x07,	/* device online */

};



struct kobject {

lib/kobject_uevent.c

+4 −0
Original line number Diff line number Diff line
@@ -38,6 +38,10 @@ static char *action_to_string(enum kobject_action action) 
		return "remove";

	case KOBJ_CHANGE:

		return "change";

	case KOBJ_MOUNT:

		return "mount";

	case KOBJ_UMOUNT:

		return "umount";

	case KOBJ_OFFLINE:

		return "offline";

	case KOBJ_ONLINE:

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