Currently, the freezer treats all tasks as freezable, except for the kernel
threads that explicitly set the PF_NOFREEZE flag for themselves.  This
approach is problematic, since it requires every kernel thread to either
set PF_NOFREEZE explicitly, or call try_to_freeze(), even if it doesn't
care for the freezing of tasks at all.

It seems better to only require the kernel threads that want to or need to
be frozen to use some freezer-related code and to remove any
freezer-related code from the other (nonfreezable) kernel threads, which is
done in this patch.

The patch causes all kernel threads to be nonfreezable by default (ie.  to
have PF_NOFREEZE set by default) and introduces the set_freezable()
function that should be called by the freezable kernel threads in order to
unset PF_NOFREEZE.  It also makes all of the currently freezable kernel
threads call set_freezable(), so it shouldn't cause any (intentional)
change of behaviour to appear.  Additionally, it updates documentation to
describe the freezing of tasks more accurately.

[akpm@linux-foundation.org: build fixes]
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Nigel Cunningham <nigel@nigel.suspend2.net>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Don't turn the radio on until the interface is up. This saves some power in
case the driver is loaded but the card is not used.

Signed-off-by: Michal Schmidt <mschmidt@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Callers of enable_MAC() shouldn't have to worry about the bits in the
response's status word (and most of them don't). The return value is
sufficient information.

Signed-off-by: Michal Schmidt <mschmidt@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Matteo Croce reported Aironet initialization failures. They were caused by
a race in airo. airo finds a free interface name, then initializes the card
and finally registers the interface. Another device may get the same name
in the meantime.
The reason airo gets its name early is to use it in informative printks and
to name the resources it requests. The printks will be just fine without
the interface name and the resources can use the driver's name - that's
what other network drivers do anyway.
One of the talkative functions is setup_card(). It is called once before
registration and can be called later again. Let's have an empty dev->name
during the first call, so it doesn't print the ugly "airo(eth%d)" message.

Signed-off-by: Michal Schmidt <mschmidt@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

airo's kernel thread and the IRQ handler are needed only when the interface
is up.

Signed-off-by: Michal Schmidt <mschmidt@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Fix an assymetry between pci_{enable,disable}_device. airo did not disable
the PCI device when unloading the module. This caused suspend failures
after modprobe -r airo && modprobe airo.

Signed-off-by: Michal Schmidt <mschmidt@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Remove includes of <linux/smp_lock.h> where it is not used/needed.
Suggested by Al Viro.

Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc,
sparc64, and arm (all 59 defconfigs).

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The way airo.c keeps track of all its devices is complicated and buggy
as well (del_airo_dev forgets to free the memory add_airo_dev allocates).
It's cleaner to use the standard list primitives.
While we're at it, it's not necessary to put PCI cards in the list, because
the kernel already keeps track of them. We can take advantage of it and
use the .remove callback as it was meant to be.
This makes /sys/bus/pci/drivers/airo/{,un}bind work.

Signed-off-by: Michal Schmidt <mschmidt@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

It's unnecessary to check for NULL before calling kfree().

Signed-off-by: Michal Schmidt <mschmidt@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

For the places where we need a pointer to the mac header, it is still legal to
touch skb->mac.raw directly if just adding to, subtracting from or setting it
to another layer header.

This one also converts some more cases to skb_reset_mac_header() that my
regex missed as it had no spaces before nor after '=', ugh.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>