There was a race in the kmap_coherent() implementation. While we
guarded against preemption, there was nothing preventing eviction of
the pre-faulted fixmap entry from the UTLB. Under certain workloads
this would result in the fixmap entries used for cache colouring being
evicted from the UTLB in the midst of a copy_page().

In addition to pre-faulting, we also make sure to preserve the PTEs
in the kernel page table and introduce a cached PTE for kmap_coherent()
usage. This follows a similar change on MIPS ("[MIPS] Fix aliasing bug
in copy_to_user_page / copy_from_user_page").
Reported-by: NHideo Saito <saito@densan.co.jp>
Reported-by: NCHIKAMA Masaki <masaki.chikama@gmail.com>
Tested-by: NYoshihiro Shimoda <shimoda.yoshihiro@renesas.com>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Use the generic remove_memory() provided by mm/memory_hotplug.c instead.
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This follows the powerpc commit f6a61680
'[POWERPC] Fix kernel stack allocation alignment'.

SH has traditionally forced the thread order to be relative to the page
size, so there were never any situations where the same bug was
triggered by slub. Regardless, the usage of > 8kB stacks for the larger
page sizes is overkill, so we switch to using slab allocations there,
as per the powerpc change.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Because alloc_bootmem functions return the allocated memory always
zeroed, an additional call of memset on allocated memory is
unnecessary.
Signed-off-by: NMarek Skuczynski <M.Skuczynski@adbglobal.com>
Signed-off-by: NCarl Shaw <carl.shaw@st.com>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

statically initialise the cached_to_uncached offset, so that we can use
it immediatly.
Signed-off-by: NStuart Menefy <stuart.menefy@st.com>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Remove arch-specific show_mem() in favor of the generic version.

This also removes the following redundant information display:

	- free pages, printed by show_free_areas()
	- pages in slab, printed by show_free_areas()
	- free swap pages, printed by show_swap_cache_info()
	- pages in swapcache, printed by show_swap_cache_info()

where show_mem() calls show_free_areas(), which calls
show_swap_cache_info().
Signed-off-by: NJohannes Weiner <hannes@saeurebad.de>
Acked-by: NPaul Mundt <lethal@linux-sh.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Almost all users of this field need a PFN instead of a physical address,
so replace node_boot_start with node_min_pfn.

[Lee.Schermerhorn@hp.com: fix spurious BUG_ON() in mark_bootmem()]
Signed-off-by: NJohannes Weiner <hannes@saeureba.de>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: NLee Schermerhorn <lee.schermerhorn@hp.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

All architectures use an effectively identical definition of online_page(), so
just make it common code.  x86-64, ia64, powerpc and sh are actually
identical; x86-32 is slightly different.

x86-32's differences arise because it puts its hotplug pages in the highmem
zone.  We can handle this in the generic code by inspecting the page to see if
its in highmem, and update the totalhigh_pages count appropriately.  This
leaves init_32.c:free_new_highpage with a single caller, so I folded it into
add_one_highpage_init.

I also removed an incorrect comment referring to the NUMA case; any NUMA
details have already been dealt with by the time online_page() is called.

[akpm@linux-foundation.org: fix indenting]
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: NDave Hansen <dave@linux.vnet.ibm.com>
Reviewed-by: NKAMEZAWA Hiroyuki <kamez.hiroyu@jp.fujitsu.com>
Tested-by: NKAMEZAWA Hiroyuki <kamez.hiroyu@jp.fujitsu.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Christoph Lameter <clameter@sgi.com>
Acked-by: NIngo Molnar <mingo@elte.hu>
Acked-by: NYasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

sh64 doesn't provide __uncached_start, so don't reference it
unconditionally.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This saves us from having to use kmalloc() for the fixmap entries,
which is needed early for the uncached fixmap.
Signed-off-by: NStuart Menefy <stuart.menefy@st.com>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Presently most of the 29-bit physical parts do P1/P2 segmentation
with a 1:1 cached/uncached mapping, jumping between the two to
control the caching behaviour. This provides the basic infrastructure
to maintain this behaviour on 32-bit physical parts that don't map
P1/P2 at all, using a shiny new linker section and corresponding
fixmap entry.
Signed-off-by: NStuart Menefy <stuart.menefy@st.com>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Now, arch dependent code around CONFIG_MEMORY_HOTREMOVE is a mess.
This patch cleans up them. This is against 2.6.23-rc6-mm1.

 - fix compile failure on ia64/ CONFIG_MEMORY_HOTPLUG && !CONFIG_MEMORY_HOTREMOVE case.
 - For !CONFIG_MEMORY_HOTREMOVE, add generic no-op remove_memory(),
   which returns -EINVAL.
 - removed remove_pages() only used in powerpc.
 - removed no-op remove_memory() in i386, sh, sparc64, x86_64.

 - only powerpc returns -ENOSYS at memory hot remove(no-op). changes it
   to return -EINVAL.

Note:
Currently, only ia64 supports CONFIG_MEMORY_HOTREMOVE. I welcome other
archs if there are requirements and testers.
Signed-off-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

SH-2 can presently get in to some pretty bogus states, so
we tidy up the dependencies a bit and get it all building
again.

This gets us a bit closer to a functional allyesconfig
and allmodconfig, though there are still a few things to
fix up.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This enables simple hotplug support for sparsemem users. Presently
this only permits memory being added in to node 0 on ZONE_NORMAL.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Kill off a bunch of externs, and use sections.h instead..
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Currently using multiple nodes tramples the ZONE_NORMAL
max low pfn, tidy up the logic a bit to get it all working
as expected.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This implements basic sparsemem support for SH. Presently this only
uses static sparsemem, and we still permit explicit selection of
flatmem. Those boards that want sparsemem can select it as usual.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

- setup-sh7750.c only defines the sh7751_ipr_map when building
  with SH7751 support.

- 7722 Solution Engine was missing a mach-type entry, causing
  the macro in cf-enabler to be undefined.

- arch/sh/mm/init.c needs linux/pagemap.h.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Spelling fixes in arch/sh/.
Signed-off-by: NSimon Arlott <simon@fire.lp0.eu>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This moves SH over to the generic quicklists. As per x86_64,
we have special mappings for the PGDs, so these go on their
own list..
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This reworks some of the node 0 bootmem initialization in
preparation for discontigmem and sparsemem support.

ARCH_POPULATES_NODE_MAP is switched to as a result of this.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Rename the existing flush routines to local_ variants for use by
the IPI-backed global flush routines on SMP.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Previously this was implemented using a global cache, cache
this per-CPU instead and bump up the number of context IDs to
match NR_CPUS.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

sh / sh64: Remove ZONE_DMA remains.

Both arches do not need ZONE_DMA
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NYoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

There were a number of places that made evil PAGE_SIZE == 4k
assumptions that ended up breaking when trying to play with
8k and 64k page sizes, this fixes those up.

The most significant change is the way we load THREAD_SIZE,
previously this was done via:

	mov	#(THREAD_SIZE >> 8), reg
	shll8	reg

to avoid a memory access and allow the immediate load. With
a 64k PAGE_SIZE, we're out of range for the immediate load
size without resorting to special instructions available in
later ISAs (movi20s and so on). The "workaround" for this is
to bump up the shift to 10 and insert a shll2, which gives a
bit more flexibility while still being much cheaper than a
memory access.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Remove extra bits from the pmd structure and store a kernel logical
address rather than a physical address. This allows it to be directly
dereferenced. Another piece of wierdness inherited from x86.
Signed-off-by: NStuart Menefy <stuart.menefy@st.com>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Add TTB accessor functions and give it a sensible default
value. We will use this later for optimizing the fault
path.
Signed-off-by: NStuart Menefy <stuart.menefy@st.com>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This adds some preliminary support for the SH-X2 MMU, used by
newer SH-4A parts (particularly SH7785).

This MMU implements a 'compat' mode with SH-X MMUs and an
'extended' mode for SH-X2 extended features. Extended features
include additional page sizes (8kB, 4MB, 64MB), as well as the
addition of page execute permissions.

The extended mode attributes are placed in a second data array,
which requires us to switch to 64-bit PTEs when in X2 mode.

With the addition of the exec perms, we also overhaul the mmap
prots somewhat, now that it's possible to handle them more
intelligently.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This implements initial support for the vsyscall page on SH.
At the moment we leave it configurable due to having nommu
to support from the same code base. We hook it up for the
signal trampoline return at present, with more to be added
later, once uClibc catches up.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This was previously unimplemented..
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This fixes up some of the various outstanding nommu bugs on
SH.
Signed-off-by: NYoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Cleanup of page table allocators, using generic folded PMD and PUD
helpers. TLB flushing operations are moved to a more sensible spot.

The page fault handler is also optimized slightly, we no longer waste
cycles on IRQ disabling for flushing of the page from the ITLB, since
we're already under CLI protection by the initial exception handler.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Signed-off-by: NJörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: NAdrian Bunk <bunk@stusta.de>

set_page_count usage outside mm/ is limited to setting the refcount to 1.
Remove set_page_count from outside mm/, and replace those users with
init_page_count() and set_page_refcounted().

This allows more debug checking, and tighter control on how code is allowed
to play around with page->_count.
Signed-off-by: NNick Piggin <npiggin@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

There was only one board using this (hp690 specifically), and it just so
happens that it's only physically discontiguous at the "normal" P1 offset.  If
we bump up the P1 offset, it's possible to hit a shadowed region of memory
where we suddenly become magically contiguous.

As people have been using this shadowed region workaround for quite some time
(and without any adverse effects), it's time to drop the left over discontig
bits that no longer have any practical use (it was always very much
hp690-centric to begin with).
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>