In preparation for supporting greater than 64 partitions replace partid_t by
short in drivers/misc/sgi-xp.
Signed-off-by: NDean Nelson <dcn@sgi.com>
Acked-by: NRobin Holt <holt@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Make XP return values more generic to XP and not so tied to XPC by changing
enum xpc_retval to xp_retval, along with changing return value prefixes from
xpc to xp.  Also, cleanup a comment block that referenced some of these return
values as well as the handling of BTE related return values.
Signed-off-by: NDean Nelson <dcn@sgi.com>
Acked-by: NRobin Holt <holt@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Addressed issues raised by scripts/checkpatch.pl. Removed unnecessary curly
braces. Eliminated uses of volatiles and use of kernel_thread() and daemonize().
Signed-off-by: NDean Nelson <dcn@sgi.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>

Ran patches through scripts/Lindent (part 1).
Signed-off-by: NDean Nelson <dcn@sgi.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>

Move XPC and XPNET from arch/ia64/sn/kernel to drivers/misc/sgi-xp.
Signed-off-by: NDean Nelson <dcn@sgi.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>

I neglected to send Tony the most recent version of the
patch ("Fix Altix BTE error return status") applied
as commit: 64135fa9

This patch gets it up to date.  Without this patch
on shub2, if there is no error xpcBteUnmappedError is
returned instead of xpcSuccess.

Signed-off-by: Russ Anderson (rja@sgi.com)
Signed-off-by: NTony Luck <tony.luck@intel.com>

The Altix shub2 BTE error detail bits are in a different location
than on shub1.  The current code does not take this into account
resulting in all shub2 BTE failures mapping to "unknown".

This patch reads the error detail bits from the proper location,
so the correct BTE failure reason is returned for both shub1
and shub2.
Signed-off-by: NRuss Anderson <rja@sgi.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>

This patch eliminates a potential deadlock that is possible when XPC
disconnects a channel to a partition that has gone down. This deadlock will
occur if at least one of the kthreads created by XPC for the purpose of making
callouts to the channel's registerer is detained in the registerer and will
not be returning back to XPC until some registerer request occurs on the now
downed partition. The potential for a deadlock is removed by ensuring that
there always is a kthread available to make the channel disconnecting callout
to the registerer.
Signed-off-by: NDean Nelson <dcn@sgi.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Jack Steiner identified a problem where XPC can cause a silent
data corruption.  On module load, the placement may cause the
xpc_remote_copy_buffer to span two physical pages.  DMA transfers are
done to the start virtual address translated to physical.

This patch changes the buffer from a statically allocated buffer to a
kmalloc'd buffer.  Dean Nelson reviewed this before posting.  I have
tested it in the configuration that was showing the memory corruption
and verified it works.  I also added a BUG_ON statement to help catch
this if a similar situation is encountered.
Signed-off-by: NRobin Holt <holt@sgi.com>
Signed-off-by: NDean Nelson <dcn@sgi.com>
Signed-off-by: NJack Steiner <steiner@sgi.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>

Fix some sparse warnings on ia64.  Large constants that should be long
instead of int.  Use NULL instead of 0.  Add some missing __iomem
casts.  Replace a non-C99 structure assignment.
Signed-off-by: NKeith Owens <kaos@sgi.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>

Signed-off-by: NDavid Woodhouse <dwmw2@infradead.org>

Take advantage of kzalloc() as well as reduce the size of code generated
for the error returns in xpc_setup_infrastructure().
Signed-off-by: NJes Sorensen <jes@sgi.com>
Acked-by: NDean Nelson <dcn@sgi.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>

Fix XPC so that it does not deliver any messages until the connected
callout has returned, as well as, prevent the disconnected callout to
occur before the disconnecting callout has returned.
Signed-off-by: NDean Nelson <dcn@sgi.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>

Migrate sn2 code to use mutex and completion events rather than
semaphores.
Signed-off-by: NJes Sorensen <jes@sgi.com>
Acked-by: NDean Nelson <dcn@sgi.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>

Cleanup a few items after moving xpc.h from arch/ia64/sn/kernel to
include/asm-ia64/sn.
Signed-off-by: NDean Nelson <dcn@sgi.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>

Move xpc.h from arch/ia64/sn/kernel to include/asm-ia64/sn without change.
Signed-off-by: NDean Nelson <dcn@sgi.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>

Cleanup the XPC disengage related messages that are printed to the log.
Signed-off-by: NDean Nelson <dcn@sgi.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>

This patch fixes a problem in XPC disengage processing whereby it was not
seeing the request to disengage from a remote partition, so the disengage
wasn't happening. The disengagement is suppose to transpire during the time
a XPC channel is disconnecting, and should be completed before the channel
is declared to be disconnected.
Signed-off-by: NDean Nelson <dcn@sgi.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>

XPC (as in arch/ia64/sn/kernel/xp*) has a need to notify other partitions
(SGI Altix) whenever a partition is going down in order to get them to
disengage from accessing the halting partition's memory. If this is not
done before the reset of the hardware, the other partitions can find
themselves encountering MCAs that bring them down.
Signed-off-by: NDean Nelson <dcn@sgi.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

XPC needs to be changed to support up to 16k nasids on an SGI Altix system.
Signed-off-by: NDean Nelson <dcn@sgi.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>

This patch addresses a few issues with the open/close protocol that
were revealed by the newly added disengage functionality combined
with more extensive testing.
Signed-off-by: NDean Nelson <dcn@sgi.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>

When XPC is being shutdown (i.e., rmmod, reboot) it doesn't ensure that
other partitions with whom it was connected have completely disengaged
from any attempt at cross-partition memory references. This can lead to
MCAs in any of these other partitions when the partition is reset.
Signed-off-by: NDean Nelson <dcn@sgi.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>

Gcc4 doesn't like volatile casts as lvalues.  Make the structure members
volatile instead.
Signed-off-by: NDave Jones <davej@redhat.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch contains the communication module (XPC) for cross partition
communication on a partitioned SGI Altix.
Signed-off-by: NDean Nelson <dcn@sgi.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>