From: Pat Gefre <pfg@sgi.com>

More code clean up - this time ioconfig_bus.c

From: Pat Gefre <pfg@sgi.com>

Small check for invalid node in shub ioctl function

From: Pat Gefre <pfg@sgi.com>

Remove __ASSEMBLY__ tags from shubio.h

From: Pat Gefre <pfg@sgi.com>

Some more minor clean up

From: Pat Gefre <pfg@sgi.com>

A few small clean ups

From: Pat Gefre <pfg@sgi.com>

Moved code out of pciio and into its own file - snia_if.c and renamed the
functions

pciio clean up

From: Pat Gefre <pfg@sgi.com>

Some small bte code clean ups

From: Pat Gefre <pfg@sgi.com>

hcl.c clean up for init failures and OOM

From: Pat Gefre <pfg@sgi.com>

Fix a couple of compiler warnings

From: Pat Gefre <pfg@sgi.com>

Mostly code pruning - a couple of adds due to the clean up

From: Pat Gefre <pfg@sgi.com>

irq clean up and update

From: Pat Gefre <pfg@sgi.com>

General xtalk.c clean up

From: Pat Gefre <pfg@sgi.com>

shubio.c cleanup

From: Pat Gefre <pfg@sgi.com>

General module.c clean up

From: Pat Gefre <pfg@sgi.com>

More klgraph.c clean up
Remove is_specified

From: Pat Gefre <pfg@sgi.com>

klgraph.c clean up

From: Pat Gefre <pfg@sgi.com>

New code for Opus and CGbrick
More minor clean up

From: Pat Gefre <pfg@sgi.com>

Fix the last patch - missed an IS_PIC_SOFT and needed the CG definition

Header file clean up
Added some __init definitions for functions that were init only
Removed some 'porting' code - replaced it with linux calls/defintions
Cleaned up some of the types we were using (ones that had been added)
Fixed include files that had the wrong path in their ifdef'd names

From: Pat Gefre <pfg@sgi.com>

Fix the last patch - missed an IS_PIC_SOFT and needed the CG definition

From: Pat Gefre <pfg@sgi.com>

Remove the bridge and xbridge code - everything not PIC

From: Pat Gefre <pfg@sgi.com>

General clean up of xbow.c

From: Pat Gefre <pfg@sgi.com>

machvec/pci.c clean up
Other clean up related to above

From: Pat Gefre <pfg@sgi.com>

General code clean up of sn/io/io.c

From: Pat Gefre <pfg@sgi.com>

Delete invent.h
Delete sgi_if.c
Cleaned up some of the NEW/DEL calls

From: Pat Gefre <pfg@sgi.com>

Kill the arcs/*.h files
Some general clean up on klconfig.h

From: Pat Gefre <pfg@sgi.com>

Kill nag.h

From: Pat Gefre <pfg@sgi.com>
      Jesse Barnes <jbarnes@tomahawk.engr.sgi.com>

From: Pat Gefre <pfg@sgi.com>

remove unused enum

From: Pat Gefre <pfg@sgi.com>

kill $Id$

From: Pat Gefre <pfg@sgi.com>

kill big endian stuff

From: Pat Gefre <pfg@sgi.com>

namespace cleanup: ioerror_dump->sn_ioerror_dump

From: Pat Gefre <pfg@sgi.com>

copyright update

From: Pat Gefre <pfg@sgi.com>

Some hwgraph code clean up

From: "H. Peter Anvin" <hpa@zytor.com>

Declaring a function to return a const scalar value is pretty meaningless. 
These functions are really trying to say that they don't alter any external
state.

Fix that up by using __attribute__((const)), if the compiler supports that.

From: Martin Schwidefsky <schwidefsky@de.ibm.com>

Fix endless loop in get_user_pages() on s390.  It happens only on s/390
because pte_dirty always returns 0.  For all other architectures this is an
optimization.

In the case of "write && !pte_dirty(pte)" follow_page() returns NULL.  On all
architectures except s390 handle_pte_fault() will then create a pte with
pte_dirty(pte)==1 because write_access==1.  In the following, second call to
follow_page() all is fine.  With the physical dirty bit patch pte_dirty() is
always 0 for s/390 because the dirty bit doesn't live in the pte.

From: Martin Schwidefsky <schwidefsky@de.ibm.com>

while searching for a s390 tlb flush problem I noticed some superflous tlb
flushes.  One in zeromap_page_range, one in remap_page_range, and another one
in filemap_sync.  The patch just adds comments but I think these three
flush_tlb_range calls can be removed.

From: Martin Schwidefsky <schwidefsky@de.ibm.com>

Ok, its just the revert of the page_cache_release delta.

From: Martin Schwidefsky <schwidefsky@de.ibm.com>

while working on my mm patch for s390 I played with rmap a bit, adding
BUG statements and the like. While doing so I noticed some room for
improvement in rmap. Its minor stuff but anyway... 

The first observation is that the pte chain array doesn't have holes,
meaning that from the pte_chain_idx() of the first array every slot of
all following pte chain arrays are full. That is there can't be NULL
pointers. The "if (!pte_paddr)" check in try_to_unmap() can be removed
and if the loop in page_referenced() is started from pte_chain_idx(pc)
then the "if (!pte_paddr)" in page_referenced() can be removed as well.

The second observation is that the first pte array of a pte chain has
at least one entry. Empty pte chain arrays are always freed immediatly
after the last entry was removed. Because of that victim_i can be
calculated in a simpler way. Instead of setting victim_i to -1 and then
check in each loop iteration against -1 victim_i can just be set to
the pte_chain_idx of the first pte chain array.

From: Martin Schwidefsky <schwidefsky@de.ibm.com>

I think I found a potential race in install_page/install_file_pte. The
inline function zap_pte releases pages by calling page_remove_rmap and
page_cache_release.  If this was the last user of a page it can get
purged from the page cache and then get immediatly reused. But there
might still be a tlb for this page on another cpu. The tlb is removed
in the callers of zap_pte, install_page and install_file_pte, but this
is too late. I admit that its a very unlikely race but never the less..

I fixed this by using the new ptep_clear_flush function that is introduced
with the tlb flush optimization patch for s/390.

From: Martin Schwidefsky <schwidefsky@de.ibm.com>

this is another s/390 related mm patch. It introduces the concept of
physical dirty and referenced bits into the common mm code. I always
had the nagging feeling that the pte functions for setting/clearing
the dirty and referenced bits are not appropriate for s/390. It works
but it is a bit of a hack. 
After the wake of rmap it is now possible to put a much better solution
into place. The idea is simple: since there are not dirty/referenced
bits in the pte make these function nops on s/390 and add operations
on the physical page to the appropriate places. For the referenced bit
this is the page_referenced() function. For the dirty bit there are
two relevant spots: in page_remove_rmap after the last user of the
page removed its reverse mapping and in try_to_unmap after the last
user was unmapped. There are two new functions to accomplish this:

 * page_test_and_clear_dirty: Test and clear the dirty bit of a
   physical page. This function is analog to ptep_test_and_clear_dirty
   but gets a struct page as argument instead of a pte_t pointer.

 * page_test_and_clear_young: Test and clear the referenced bit
   of a physical page. This function is analog to ptep_test_and_clear_young
   but gets a struct page as argument instead of a pte_t pointer.

Its pretty straightforward and with it the s/390 mm makes much more
sense. You'll need the tls flush optimization patch for the patch.
Comments ?