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: Robin Holt <holt@sgi.com>
Signed-off-by: Dean Nelson <dcn@sgi.com>
Signed-off-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Take advantage of kzalloc() as well as reduce the size of code generated
for the error returns in xpc_setup_infrastructure().
Signed-off-by: Jes Sorensen <jes@sgi.com>
Acked-by: Dean Nelson <dcn@sgi.com>
Signed-off-by: Tony 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: Dean Nelson <dcn@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Cleanup the XPC disengage related messages that are printed to the log.
Signed-off-by: Dean Nelson <dcn@sgi.com>
Signed-off-by: Tony 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: Dean Nelson <dcn@sgi.com>
Signed-off-by: Tony 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: Dean Nelson <dcn@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Eliminate the passing in of a scratch buffer used for locating the
reserved page setup for XPC.
Signed-off-by: Dean Nelson <dcn@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
XPC needs to be changed to support up to 16k nasids on an SGI Altix system.
Signed-off-by: Dean Nelson <dcn@sgi.com>
Signed-off-by: Tony 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: Dean Nelson <dcn@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Some of the SN code & #defines related to compact nodes & IO discovery
have gotten stale over the years. This patch attempts to clean them up.
Some of the various SN MAX_xxx #defines were also unclear & misused.
The primary changes are:
- use MAX_NUMNODES. This is the generic linux #define for the number
of nodes that are known to the generic kernel. Arrays & loops
for constructs that are 1:1 with linux-defined nodes should
use the linux #define - not an SN equivalent.
- use MAX_COMPACT_NODES for MAX_NUMNODES + NUM_TIOS. This is the
number of nodes in the SSI system. Compact nodes are a hack to
get around the IA64 architectural limit of 256 nodes. Large SGI
systems have more than 256 nodes. When we upgrade to ACPI3.0,
I _hope_ that all nodes will be real nodes that are known to
the generic kernel. That will allow us to delete the notion
of "compact nodes".
- add MAX_NUMALINK_NODES for the total number of nodes that
are in the numalink domain - all partitions.
- simplified (understandable) scan_for_ionodes()
- small amount of cleanup related to cnodes
Signed-off-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Tony 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: Dean Nelson <dcn@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Gcc4 doesn't like volatile casts as lvalues. Make the structure members
volatile instead.
Signed-off-by: Dave Jones <davej@redhat.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch contains the bits to make the XPC code use the uncached
allocator rather than calling into the mspec driver. It also includes the
mspec.h header which is required to build the XPC modules.
Signed-off-by: Jes Sorensen <jes@wildopensource.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch detects the existence of an uncached physical AMO address setup
by EFI's XPBOOT (SGI) and converts it to an uncached virtual AMO address.
Depends on a patch submitted on 23 March 2005 with the subject of:
[PATCH 2/3] SGI Altix cross partition functionality (2nd revision)
Signed-off-by: Dean Nelson <dcn@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
This patch contains the communication module (XPC) for cross partition
communication on a partitioned SGI Altix.
Signed-off-by: Dean Nelson <dcn@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
