Revert "ARM: sort the meminfo array earlier"

This reverts commit 8c238bb88848e19af55a29d1b3c0c3c85cb64c3f.
ARM: sort the meminfo array earlier

The meminfo array has to be sorted before sanity_check_meminfo() in
arch/arm/mm/mmu.c is called for it to work properly.  This also allows
for a simpler find_limits() in arch/arm/mm/init.c.

The sort is moved to arch/arm/kernel/setup.c because that's where the
meminfo array is populated.  Eventually this should be improved upon
to make the memory bank parser a bit more robust against problems
such as overlapping memory ranges.

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

Conflicts:
	arch/arm/kernel/setup.c
	arch/arm/mm/init.c
memblock: Kill MEMBLOCK_ERROR

25818f0f28 (memblock: Make MEMBLOCK_ERROR be 0) thankfully made
MEMBLOCK_ERROR 0 and there already are codes which expect error return
to be 0.  There's no point in keeping MEMBLOCK_ERROR around.  End its
misery.

Signed-off-by: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1310457490-3356-6-git-send-email-tj@kernel.org
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

Conflicts:
	arch/x86/kernel/aperture_64.c
	arch/x86/kernel/check.c
	arch/x86/kernel/e820.c
	arch/x86/kernel/setup.c
	arch/x86/kernel/trampoline.c
	arch/x86/mm/init.c
	arch/x86/mm/memblock.c
	arch/x86/mm/numa.c
	arch/x86/mm/numa_32.c
	arch/x86/mm/numa_emulation.c
memblock: Replace memblock_find_base() with memblock_find_in_range()

memblock_find_base() is a static function with two callers in
memblock.c and memblock_find_in_range() is a wrapper around it which
just changes the types and order of parameters.

Make memblock_find_in_range() take phys_addr_t instead of u64 for
consistency and replace memblock_find_base() with it.

Signed-off-by: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1310457490-3356-7-git-send-email-tj@kernel.org
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
memblock: Don't allow archs to override memblock_nid_range()

memblock_nid_range() is used to implement memblock_[try_]alloc_nid().
The generic version determines the range by walking early_node_map
with for_each_mem_pfn_range().  The generic version is defined __weak
to allow arch override.

Currently, only sparc overrides it; however, with the previous update
to the generic implementation, there isn't much to be gained with arch
override.  Sparc would behave exactly the same with the generic
implementation.

This patch disallows arch override for memblock_nid_range() and make
both generic and sparc versions static.

sparc is only compile tested.

Signed-off-by: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1310460395-30913-6-git-send-email-tj@kernel.org
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

Conflicts:
	arch/sparc/mm/init_64.c
memblock: Improve generic memblock_nid_range() using for_each_mem_pfn_range()

Given an address range, memblock_nid_range() determines the node the
start of the range belongs to and upto where the range stays in the
same node.

It's implemented by calling get_pfn_range_for_nid(), which determines
min and max pfns for a given node, for each node and testing whether
start address falls in there.  This is not only inefficient but also
incorrect when nodes interleave as min-max ranges for nodes overlap.

This patch reimplements memblock_nid_range() using
for_each_mem_pfn_range().  It's simpler, walks the mem ranges once and
can find the exact range the start address falls in.

Signed-off-by: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1310460395-30913-5-git-send-email-tj@kernel.org
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
memblock: Make memblock_alloc_[try_]nid() top-down

NUMA aware memblock alloc functions - memblock_alloc_[try_]nid() -
weren't properly top-down because memblock_nid_range() scanned
forward.  This patch reverses memblock_nid_range(), renames it to
memblock_nid_range_rev() and updates related functions to implement
proper top-down allocation.

Signed-off-by: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1310460395-30913-7-git-send-email-tj@kernel.org
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

Conflicts:
	mm/memblock.c
Revert "memblock: Make memblock_alloc_[try_]nid() top-down"

This reverts commit 789a79a335cf1f1d03054cb83bef9af3862db43b.
Revert "memblock: Improve generic memblock_nid_range() using for_each_mem_pfn_range()"

This reverts commit 9725a30b46a61525756554d059fc01655fefe18a.
Revert "memblock: Don't allow archs to override memblock_nid_range()"

This reverts commit 462519f64b3c1fcf8ebf80206e67ab6a8752815f.
memblock: Use MEMBLOCK_ALLOC_ACCESSIBLE instead of ANYWHERE in memblock_alloc_try_nid()

After node affine allocation fails, memblock_alloc_try_nid() calls
memblock_alloc_base() with @max_addr set to MEMBLOCK_ALLOC_ANYWHERE.
This is inconsistent with memblock_alloc() and what the function's
sole user - sparc/mm/init_64 - expects, although it doesn't make any
difference as sparc64 doesn't have highmem and ACCESSIBLE equals
ANYWHERE.

This patch makes memblock_alloc_try_nid() use ACCESSIBLE instead of
ANYWHERE.  This isn't complete as node affine allocation doesn't
consider memblock.current_limit.  It will be handled with future
changes.

This patch doesn't introduce any behavior difference.

Signed-off-by: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1310457490-3356-4-git-send-email-tj@kernel.org
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
memblock: Use round_up/down() instead of memblock_align_up/down()

Signed-off-by: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1310457490-3356-5-git-send-email-tj@kernel.org
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
mm, show_mem: suppress page counts in non-blockable contexts

commit 4b59e6c4730978679b414a8da61514a2518da512 upstream.

On large systems with a lot of memory, walking all RAM to determine page
types may take a half second or even more.

In non-blockable contexts, the page allocator will emit a page allocation
failure warning unless __GFP_NOWARN is specified.  In such contexts, irqs
are typically disabled and such a lengthy delay may even result in NMI
watchdog timeouts.

To fix this, suppress the page walk in such contexts when printing the
page allocation failure warning.

Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Conflicts:
	arch/ia64/mm/contig.c
	arch/ia64/mm/discontig.c
	arch/parisc/mm/init.c
ARM: head.S: only include __turn_mmu_on in the initial identity mapping

__create_page_tables identity maps the region of memory from
__enable_mmu to the end of __turn_mmu_on.

In preparation for including __turn_mmu_on in the .idmap.text section,
this patch modifies the identity mapping so that it only includes the
__turn_mmu_on code.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
ARM: entry: prefetch/data abort helpers: avoid corrupting r4

Replace r4 with ip for calling abort helpers - ip is allowed to be
corrupted by called functions in the ABI, so it makes more sense to
use such a register.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: entry: abort-macro: specify registers to be used for macros

Require all callers of abort macros to specify the registers to be
used.  This improves the documentation at the callsites as to which
registers are being used by this assembly code.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: entry: abort-macro: simplify do_ldrd_abort

We can test bits 27:25 and 20 of the instruction at the same time;
there's no need to separate out the check of bit 20.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: entry: no need to increase preempt count for IRQ handlers

irq_enter() and irq_exit() already take care of the preempt_count
handling for interrupts, which increment and decrement the hardirq
bits of the preempt count.  So we can remove the preempt count handing
in our IRQ entry/exit assembly, like x86 did some 9 years ago.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: entry: no need to check parent IRQ mask in IRQ handler return

There's no point checking to see whether IRQs were masked in the parent
context when returning from IRQ handling - the fact that we're handling
an IRQ means that the parent context must have had IRQs unmasked.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: add a kuser_cmpxchg64 user space helper

Some user space applications are designed around the ability to perform
atomic operations on 64 bit values.  Since this is natively possible
only with ARMv6k and above, let's provide a new kuser helper to perform
the operation with kernel supervision on pre ARMv6k hardware.

Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Tested-by: Dave Martin <dave.martin@linaro.org>

Conflicts:
	Documentation/arm/kernel_user_helpers.txt
	arch/arm/kernel/entry-armv.S