<s>
sysfs	B-Application
is	O
a	O
pseudo	B-Application
file	I-Application
system	I-Application
provided	O
by	O
the	O
Linux	B-Operating_System
kernel	I-Operating_System
that	O
exports	O
information	O
about	O
various	O
kernel	B-Operating_System
subsystems	O
,	O
hardware	O
devices	O
,	O
and	O
associated	O
device	B-Application
drivers	I-Application
from	O
the	O
kernel	B-Operating_System
's	O
device	O
model	O
to	O
user	B-Operating_System
space	I-Operating_System
through	O
virtual	O
files	O
.	O
</s>
<s>
In	O
addition	O
to	O
providing	O
information	O
about	O
various	O
devices	O
and	O
kernel	B-Operating_System
subsystems	O
,	O
exported	O
virtual	O
files	O
are	O
also	O
used	O
for	O
their	O
configuration	O
.	O
</s>
<s>
sysfs	B-Application
provides	O
functionality	O
similar	O
to	O
the	O
sysctl	B-Application
mechanism	O
found	O
in	O
BSD	B-Operating_System
operating	I-Operating_System
systems	I-Operating_System
,	O
with	O
the	O
difference	O
that	O
sysfs	B-Application
is	O
implemented	O
as	O
a	O
virtual	O
file	O
system	O
instead	O
of	O
being	O
a	O
purpose-built	O
kernel	B-Operating_System
mechanism	O
,	O
and	O
that	O
,	O
in	O
Linux	B-Operating_System
,	O
sysctl	B-Application
configuration	O
parameters	O
are	O
made	O
available	O
at	O
/proc/sys/	O
as	O
part	O
of	O
procfs	B-Application
,	O
not	O
sysfs	B-Application
which	O
is	O
mounted	O
at	O
/sys/	O
.	O
</s>
<s>
During	O
the	O
2.5	O
development	O
cycle	O
,	O
the	O
Linux	B-Application
driver	I-Application
model	O
was	O
introduced	O
to	O
fix	O
the	O
following	O
shortcomings	O
of	O
version	O
2.4	O
:	O
</s>
<s>
There	O
was	O
no	O
generic	O
hotplug	B-Device
mechanism	O
.	O
</s>
<s>
procfs	B-Application
was	O
cluttered	O
with	O
non-process	O
information	O
.	O
</s>
<s>
Sysfs	B-Application
was	O
designed	O
to	O
export	O
the	O
information	O
present	O
in	O
the	O
device	B-Operating_System
tree	I-Operating_System
which	O
would	O
then	O
no	O
longer	O
clutter	O
up	O
procfs	B-Application
.	O
</s>
<s>
Maneesh	O
Soni	O
later	O
wrote	O
the	O
sysfs	B-Application
backing	O
store	O
patch	O
to	O
reduce	O
memory	O
usage	O
on	O
large	O
systems	O
.	O
</s>
<s>
During	O
the	O
next	O
year	O
of	O
2.5	O
development	O
the	O
infrastructural	O
capabilities	O
of	O
the	O
driver	O
model	O
and	O
driverfs	B-Application
began	O
to	O
prove	O
useful	O
to	O
other	O
subsystems	O
.	O
</s>
<s>
kobjects	O
were	O
developed	O
to	O
provide	O
a	O
central	O
object	O
management	O
mechanism	O
and	O
driverfs	B-Application
was	O
renamed	O
to	O
sysfs	B-Application
to	O
represent	O
its	O
subsystem	O
agnosticism	O
.	O
</s>
<s>
Sysfs	B-Application
is	O
mounted	O
under	O
the	O
mount	O
point	O
.	O
</s>
<s>
Exports	O
information	O
about	O
ACPI	B-Device
devices	O
.	O
</s>
<s>
Exports	O
information	O
about	O
PCI	B-Protocol
and	O
PCI	B-Protocol
Express	O
devices	O
.	O
</s>
<s>
Exports	O
information	O
about	O
PCI	B-Protocol
Express	O
devices	O
.	O
</s>
<s>
Exports	O
information	O
about	O
USB	B-Protocol
devices	I-Protocol
.	O
</s>
<s>
Exports	O
information	O
about	O
mass	B-Device
storage	I-Device
devices	I-Device
,	O
including	O
USB	B-Protocol
,	O
SATA	O
and	O
NVMe	B-Application
interfaces	O
.	O
</s>
<s>
As	O
the	O
S/390	B-Device
architecture	O
contains	O
devices	O
not	O
found	O
elsewhere	O
,	O
special	O
buses	O
have	O
been	O
created	O
:	O
</s>
<s>
iucv	B-Application
:	O
Artificial	O
devices	O
like	O
netiucv	O
devices	O
which	O
use	O
VM	O
's	O
IUCV	B-Application
interface	O
.	O
</s>
<s>
Sysfs	B-Application
is	O
used	O
by	O
several	O
utilities	O
to	O
access	O
information	O
about	O
hardware	O
and	O
its	O
driver	O
(	O
kernel	B-Application
modules	I-Application
)	O
such	O
as	O
udev	B-Application
or	O
HAL	B-Application
.	O
</s>
<s>
Scripts	O
have	O
been	O
written	O
to	O
access	O
information	O
previously	O
obtained	O
via	O
procfs	B-Application
,	O
and	O
some	O
scripts	O
configure	O
device	B-Application
drivers	I-Application
and	O
devices	O
via	O
their	O
attributes	O
.	O
</s>
