This patch started life as as534, and has been re-diffed against the latest
tree.

usb-storage has a small loophole, a window between the time queuecommand
accepts a new command and the time the control thread starts to execute
it.  If disconnect is called during that window, the driver won't cancel
the pending command -- we've been relying on the SCSI core to cancel it
for us during host removal.  But it's better for usb-storage to cancel
it;  this avoids races and reduces reliance on the SCSI core.
Fortunately cancelling these commands is easy to do; the key is to do it
_before_ calling scsi_remove_host.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NMatthew Dharm <mdharm-usb@one-eyed-alien.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch started life as as533, and has been re-diffed against the
current tree.

Disconnect processing in usb-storage naturally divides into two parts:
one to quiesce the driver (make sure no commands are executing or
queued) and remove the host, and the other to deallocate all the USB and
non-USB resources.  This patch creates two subroutines to handle those
two parts.  Mostly it's just code movement, but there is one significant
change.  If the scsi-scanning thread fails to initialize but the host
has successfully been added, we need to quiesce the driver before
removing the host.  After all, it's possible that scanning could have
been initiated from somewhere else, such as userspace -- very low
probability, but it's easily handled by calling the new subroutine.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NMatthew Dharm <mdharm-usb@one-eyed-alien.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

1. Establish a simple API for process freezing defined in linux/include/sched.h:

   frozen(process)		Check for frozen process
   freezing(process)		Check if a process is being frozen
   freeze(process)		Tell a process to freeze (go to refrigerator)
   thaw_process(process)	Restart process
   frozen_process(process)	Process is frozen now

2. Remove all references to PF_FREEZE and PF_FROZEN from all
   kernel sources except sched.h

3. Fix numerous locations where try_to_freeze is manually done by a driver

4. Remove the argument that is no longer necessary from two function calls.

5. Some whitespace cleanup

6. Clear potential race in refrigerator (provides an open window of PF_FREEZE
   cleared before setting PF_FROZEN, recalc_sigpending does not check
   PF_FROZEN).

This patch does not address the problem of freeze_processes() violating the rule
that a task may only modify its own flags by setting PF_FREEZE. This is not clean
in an SMP environment. freeze(process) is therefore not SMP safe!
Signed-off-by: NChristoph Lameter <christoph@lameter.com>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!