Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Mtdblock driver doesn't call flush_dcache_page for pages in request.  So,
this causes problems on architectures where the icache doesn't fill from
the dcache or with dcache aliases.  The patch fixes this.

The ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE symbol was introduced to avoid
pointless empty cache-thrashing loops on architectures for which
flush_dcache_page() is a no-op.  Every architecture was provided with this
flush pages on architectires where ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE is
equal 1 or do nothing otherwise.

See "fix mtd_blkdevs problem with caches on some architectures" discussion
on LKML for more information.
Signed-off-by: NIlya Loginov <isloginov@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Peter Horton <phorton@bitbox.co.uk>
Cc: "Ed L. Cashin" <ecashin@coraid.com>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

This fixes up the kmap_coherent/kunmap_coherent() interface for recent
changes both in the page fault path and the shared cache flushers, as
well as adding in some optimizations.

One of the key things to note here is that the TLB flush itself is
deferred until the unmap, and the call in to update_mmu_cache() itself
goes away, relying on the regular page fault path to handle the lazy
dcache writeback if necessary.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This does a bit of rework for making the cache flushers SMP-aware. The
function pointer-based flushers are renamed to local variants with the
exported interface being commonly implemented and wrapping as necessary.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

All CPU-specific overloads are done at runtime now, so this common header
can go away and simply be folded back in to asm/ version.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This paves the way for allowing individual CPUs to overload the
individual flushing routines that they care about without having to
depend on weak aliases. SH-4 is converted over initially, as it wires
up pretty much everything. The majority of the other CPUs will simply use
the default no-op implementation with their own region flushers wired up.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

We use flush_cache_page() outright in copy_to_user_page(), and nothing
else needs it, so just kill it off. SH-5 still defines its own version,
but that too will go away in the same fashion once it converts over.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

All of the flush_dcache_mmap_lock()/flush_dcache_mmap_unlock()
definitions are identical across all CPUs, so just provide them
generically in asm/cacheflush.h.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This provides a central point for CPU cache initialization routines.
This replaces the antiquated p3_cache_init() method, which the vast
majority of CPUs never cared about.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This does a bit of reorganizing for allowing nommu to use the new
and generic cache.c, no functional changes.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This builds in the newly created cache.c (renamed from pg-mmu.c) for both
MMU and NOMMU configurations. The kmap_coherent() stubs and alias
information recorded by each CPU family takes care of doing the right
thing while enabling the code to be commonly shared.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This plugs in kmap_coherent() for the non-SH4 cases to permit the
pg-mmu.c bits to be used generically across all CPUs. SH-5 is still in
the TODO state, but will move over to fixmap and the generic interface
gradually.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This provides a __flush_anon_page() that handles both the aliasing and
non-aliasing cases. This fixes up some crashes with heavy
get_user_pages() users.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Now that the SH-4 page clear/copy ops are generic, they can be used for
all platforms with CONFIG_MMU=y. SH-5 remains the odd one out, but it too
will gradually be converted over to using this interface.

SH-3 platforms which do not contain aliases will see no impact from this
change, while aliasing SH-3 platforms will get the same interface as
SH-4.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This wires up clear_user_highpage() on SH-4 and subsequently converts the
SH7705 32kB cache mode over to using it. Now that the SH-4 implementation
handles all of the dcache purging directly in the aliasing case, there is
no need to do this in the default clear_page() implementation.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Presently shm_align_mask is only looked at for the bottom up case, but we
still want this for proper colouring constraints in the topdown case.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This follows the sparc changes a439fe51.

Most of the moving about was done with Sam's directions at:

http://marc.info/?l=linux-sh&m=121724823706062&w=2

with subsequent hacking and fixups entirely my fault.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

In the do_execve() path, argument page handling used to explicitly call
flush_dcache_page() for each page, this has since been reworked and
uses flush_kernel_dcache_page() instead, which is presently a nop.

Doing a simple modprobe/rmmod in a loop under busybox consistently
manages to crash without providing a sane flush_kernel_dcache_page()
implementation, so, plug in a simple implementation.
Signed-off-by: NCarmelo Amoroso <carmelo73@gmail.com>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Signed-off-by: NHeiko Schocher <heiko.schocher@invitel.hu>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This moves copy_{to,from}_user_page() out-of-line on SH-4 and
converts for the kmap_coherent() API. Based on the MIPS
implementation.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This reworks the cache mode configuration in Kconfig, and allows for
explicit selection of write-back/write-through/off configurations.
All of the cache flushing routines are optimized away for the off
case.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

These ended up causing too many problems on older parts,
revert for now..
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This converts the lazy dcache handling to the model described in
Documentation/cachetlb.txt and drops the ptep_get_and_clear() hacks
used for the aliasing dcaches on SH-4 and SH7705 in 32kB mode. As a
bonus, this slightly cuts down on the cache flushing frequency.

With that and the PTEA handling out of the way, the update_mmu_cache()
implementations can be consolidated, and we no longer have to worry
about which configuration the cache is in for the SH7705 case.

And finally, explicitly disable the lazy writeback on SMP (SH-4A).
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Set the SHM alignment at runtime, based off of probed cache desc.
Optimize get_unmapped_area() to only colour align shared mappings.
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>

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!