We have received multiple reports of mmap failures when running with a
2:2 vm split. These manifest as either -EINVAL with a non page-aligned
address (ending 0xaaa) or a SEGV, depending on the application. The
issue is commonly observed in children of make, which appears to use
bottom-up mmap (assumedly because it changes the stack rlimit).

Further investigation reveals that this regression was triggered by
394ef6403abc ("mm: use vm_unmapped_area() on arm architecture"), whereby
TASK_UNMAPPED_BASE is no longer page-aligned for bottom-up mmap, causing
get_unmapped_area to choke on misaligned addressed.

This patch fixes the problem by defining TASK_UNMAPPED_BASE in terms of
TASK_SIZE and explicitly aligns the result to 16M, matching the other
end of the heap.

Acked-by: Nicolas Pitre <nico@linaro.org>
Reported-by: Steve Capper <steve.capper@arm.com>
Reported-by: Jean-Francois Moine <moinejf@free.fr>
Reported-by: Christoffer Dall <cdall@cs.columbia.edu>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

With ixp2xxx removed, there are no platforms that define arch_is_coherent,
so the last occurrences of arch_is_coherent can be removed. Any new
platform with coherent i/o should use coherent dma mapping functions.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>

During the p2v changes, the PHYS_OFFSET #define moved into a
!__ASSEMBLY__ section. This causes a XIP build to fail with

 arch/arm/kernel/head.o: In function 'stext':
 arch/arm/kernel/head.S:146: undefined reference to 'PHYS_OFFSET'

Momentarily leave the #ifndef __ASSEMBLY__ section so we can
define PHYS_OFFSET for all compilation units.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Signed-off-by: Alessandro Rubini <rubini@gnudd.com>
Acked-by: Giancarlo Asnaghi <giancarlo.asnaghi@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

XIP_VIRT_ADDR is needed for XIP builds and currently only defined for
builds with CONFIG_MMU.

Also provide it for no-MMU builds to make it possible to build an XIP
kernel for MMU-less machines. As these lack an MMU it has to be an
identity mapping.

Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Given that we want the default to not have any <mach/memory.h> and given
that there are now fewer cases where it is still provided than the cases
where it is not at this point, this makes sense to invert the logic and
just identify the exception cases.

The word "need" instead of "have" was chosen to construct the config
symbol so not to suggest that having a mach/memory.h file is actually
a feature that one should aim for.

Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>

When the CONFIG_NO_MACH_MEMORY_H symbol is selected by a particular
machine class, the machine specific memory.h include file is no longer
used and can be removed.  In that case the equivalent information can
be obtained dynamically at runtime by enabling CONFIG_ARM_PATCH_PHYS_VIRT
or by specifying the physical memory address at kernel configuration time.

If/when all instances of mach/memory.h are removed then this symbol could
be removed.

Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>

Conflicts:
	arch/arm/mach-msm/board-msm7x30.c

This function can be called during boot to increase the size of the consistent
DMA region above it's default value of 2MB. It must be called before the memory
allocator is initialised, i.e. before any core_initcall.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>

This code can be removed now that MSM targets no longer need the 16-bit
offsets for P2V.

Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>