• Milan Broz's avatar
    dm: add name and uuid to sysfs · 784aae73
    Milan Broz authored
    Implement simple read-only sysfs entry for device-mapper block device.
    
    This patch adds a simple sysfs directory named "dm" under block device
    properties and implements
    	- name attribute (string containing mapped device name)
    	- uuid attribute (string containing UUID, or empty string if not set)
    
    The kobject is embedded in mapped_device struct, so no additional
    memory allocation is needed for initializing sysfs entry.
    
    During the processing of sysfs attribute we need to lock mapped device
    which is done by a new function dm_get_from_kobj, which returns the md
    associated with kobject and increases the usage count.
    
    Each 'show attribute' function is responsible for its own locking.
    Signed-off-by: default avatarMilan Broz <mbroz@redhat.com>
    Signed-off-by: default avatarAlasdair G Kergon <agk@redhat.com>
    784aae73
dm.c 35.4 KB