Commit Graph

377585 Commits

Author SHA1 Message Date
Catalin Marinas
ff3986a150 arm64: locks: Remove CONFIG_GENERIC_LOCKBREAK
Commit 52ea2a560a (arm64: locks: introduce ticket-based spinlock
implementation) introduces the arch_spin_is_contended() function making
CONFIG_GENERIC_LOCKBREAK unnecessary.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
(cherry picked from commit 61c77e0802)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 20:00:56 +01:00
T.J. Purtell
3cf0e16070 arm64: compat: Clear the IT state independent of the 32-bit ARM or Thumb-2 mode
The ARM architecture reference specifies that the IT state bits in the
PSR must be all zeros in ARM mode or behavior is unspecified. If an ARM
function is registered as a signal handler, and that signal is delivered
inside a block of instructions following an IT instruction, some of the
instructions at the beginning of the signal handler may be skipped if
the IT state bits of the Program Status Register are not cleared by the
kernel.

Signed-off-by: T.J. Purtell <tj@mobisocial.us>
[catalin.marinas@arm.com: code comment and commit log updated]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

(cherry picked from commit aa62c20911)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 20:00:56 +01:00
Catalin Marinas
4b905a8fda arm64: Use 42-bit address space with 64K pages
This patch expands the VA_BITS to 42 when the 64K page configuration is
enabled allowing 2TB kernel linear mapping. Linux still uses 2 levels of
page tables in this configuration with pgd now being a full page.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
(cherry picked from commit 847264fb7e)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 20:00:55 +01:00
Marc Zyngier
d5c5e6a15e arm64: fix access to preempt_count from assembly code
preempt_count is defined as an int. Oddly enough, we access it
as a 64bit value. Things become interesting when running a BE
kernel, and looking at the current CPU number, which is stored
as an int next to preempt_count. Like in a per-cpu interrupt
handler, for example...

Using a 32bit access fixes the issue for good.

Cc: Matthew Leach <matthew.leach@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 717321fcb5)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 20:00:55 +01:00
Mark Salter
b35f594dc7 arm64: use generic RW_DATA_SECTION macro in linker script
The .data section in the arm64 linker script currently lacks a
definition for page-aligned data. This leads to a .page_aligned
section being placed between the end of data and start of bss.
This patch corrects that by using the generic RW_DATA_SECTION
macro which includes support for page-aligned data.

Signed-off-by: Mark Salter <msalter@redhat.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 3c620626c0)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 20:00:55 +01:00
Robin Murphy
b357e64d1f arm64: update 32-bit kuser helpers to ARMv8
This patch updates the barrier semantics in the kuser helper functions
to take advantage of the ARMv8 additions to AArch32, which are
guaranteed to be available in situations where these functions will be
called.

Note that this slightly changes the cmpxchg functions in that they are
no longer necessarily full barriers if they return 1. However, the
documentation only states they include their own barriers "as needed",
not that they are obligated to act as a full barrier for the caller.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
CC: Matthew Leach <matthew.leach@arm.com>
CC: Dave Martin <dave.martin@arm.com>
CC: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit d0f38f9130)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 20:00:55 +01:00
Catalin Marinas
9109f9215e arm64: Export __copy_in_user() to modules
This function may be called from loadable modules, so it needs
exporting.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: Loc Ho <lho@apm.com>
(cherry picked from commit 2a3f912c78)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 20:00:54 +01:00
Will Deacon
9e7ced5a24 arm64: cmpxchg: implement cmpxchg64_relaxed
This patch introduces cmpxchg64_relaxed for arm64 using the existing
cmpxchg_local macro, which performs a cmpxchg operation (up to 64 bits)
without barrier semantics.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit cf10b79a7d)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 20:00:54 +01:00
Will Deacon
9f89c68bf6 arm64: lockref: add support for lockless lockrefs using cmpxchg
Our spinlocks are only 32-bit (2x16-bit tickets) and our cmpxchg can
deal with 8-bytes (as one would hope!).

This patch wires up the cmpxchg-based lockless lockref implementation
for arm64.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 5686b06cea)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 20:00:54 +01:00
Will Deacon
5aa580e940 arm64: locks: introduce ticket-based spinlock implementation
This patch introduces a ticket lock implementation for arm64, along the
same lines as the implementation for arch/arm/.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 52ea2a560a)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 20:00:53 +01:00
Loc Ho
e9b67be1af clk: arm64: Add DTS clock entry for APM X-Gene Storm SoC
clk: arm64: Add DTS clock entry for APM X-Gene Storm SoC with reference to
reference, PCP PLL, SoC PLL, and Ethernet clocks.

Signed-off-by: Loc Ho <lho@apm.com>
Signed-off-by: Kumar Sankaran <ksankaran@apm.com>
Signed-off-by: Vinayak Kale <vkale@apm.com>
Signed-off-by: Feng Kan <fkan@apm.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
(cherry picked from commit 3eb15d84e3)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 20:00:46 +01:00
Steve Capper
9d6eaf2f91 arm64: Widen hwcap to be 64 bit
Under arm64 elf_hwcap is a 32 bit quantity, but it is stored in
a 64 bit auxiliary ELF field and glibc reads hwcap as 64 bit.

This patch widens elf_hwcap to be 64 bit.

Signed-off-by: Steve Capper <steve.capper@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 25804e6a96)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 20:00:46 +01:00
Catalin Marinas
37f03baee4 arm64: Correctly report LR and SP for compat tasks
When a task crashes and we print debugging information, ensure that
compat tasks show the actual AArch32 LR and SP registers rather than the
AArch64 ones.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 6ca68e8026)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 20:00:46 +01:00
Catalin Marinas
08868ba57e arm64: Make do_bad_area() function static
This function is only called from arch/arm64/mm/fault.c.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 59f67e16e6)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 20:00:45 +01:00
Will Deacon
f164a6c211 arm64: mm: permit use of tagged pointers at EL0
TCR.TBI0 can be used to cause hardware address translation to ignore the
top byte of userspace virtual addresses. Whilst not especially useful in
standard C programs, this can be used by JITs to `tag' pointers with
various pieces of metadata.

This patch enables this bit for AArch64 Linux, and adds a new file to
Documentation/arm64/ which describes some potential caveats when using
tagged virtual addresses.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit d50240a5f6)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 20:00:45 +01:00
Dan Aloni
760b97f095 Move the EM_ARM and EM_AARCH64 definitions to uapi/linux/elf-em.h
Signed-off-by: Dan Aloni <alonid@stratoscale.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 909e3ee411)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 20:00:45 +01:00
Will Deacon
0fa5264c3f arm64: delay: don't bother reporting bogomips in /proc/cpuinfo
We always use a timer-backed delay loop for arm64, so don't bother
reporting a bogomips value which appears to confuse some people.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 326b16db9f)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 20:00:29 +01:00
Catalin Marinas
6d5002154f arm64: Fix mapping of memory banks not ending on a PMD_SIZE boundary
The map_mem() function limits the current memblock limit to PGDIR_SIZE
(the initial swapper_pg_dir mapping) to avoid create_mapping()
allocating memory from unmapped areas. However, if the first block is
within PGDIR_SIZE and not ending on a PMD_SIZE boundary, when 4K page
configuration is enabled, create_mapping() will try to allocate a pte
page. Such page may be returned by memblock_alloc() from the end of such
bank (or any subsequent bank within PGDIR_SIZE) which is not mapped yet.

The patch limits the current memblock limit to the aligned end of the
first bank and gradually increases it as more memory is mapped. It also
ensures that the start of the first bank is aligned to PMD_SIZE to avoid
pte page allocation for this mapping.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: "Leizhen (ThunderTown, Euler)" <thunder.leizhen@huawei.com>
Tested-by: "Leizhen (ThunderTown, Euler)" <thunder.leizhen@huawei.com>
(cherry picked from commit e25208f77c)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 20:00:29 +01:00
Mark Brown
c3efb58a10 Merge remote-tracking branch 'lsk/v3.10/topic/arm64-hugepages' into lsk-v3.10-arm64-misc 2014-05-15 20:00:16 +01:00
Mark Salter
60d914abab arm64: move elf notes into readonly segment
The current vmlinux.lds.S places the notes sections between the
end of rw data and start of bss. This means that _edata doesn't
really point to the end of data. Since notes are read-only, this
patch moves them to the read-only segment so that _edata does
point to the end of initialized rw data.

Signed-off-by: Mark Salter <msalter@redhat.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit c80b7ee852)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 19:59:56 +01:00
Catalin Marinas
0195e1c67c arm64: Enable interrupts in the EL0 undef handler
do_undefinstr() has to be called with interrupts disabled since it may
read the instruction from the user address space which could lead to a
data abort and subsequent might_sleep() warning in do_page_fault().

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 2600e130b3)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 19:59:56 +01:00
Roy Franz
3033aae67a arm64: Expand arm64 image header
Expand the arm64 image header to allow for co-existance with
PE/COFF header required by the EFI stub.  The PE/COFF format
requires the "MZ" header to be at offset 0, and the offset
to the PE/COFF header to be at offset 0x3c.  The image
header is expanded to allow 2 instructions at the beginning
to accommodate a benign intruction at offset 0 that includes
the "MZ" header, a magic number, and the offset to the PE/COFF
header.

Signed-off-by: Roy Franz <roy.franz@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 4370eec05a)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 19:59:56 +01:00
Chen Gang
52e83d9043 ARM64: include: asm: include "asm/types.h" in "pgtable-2level-types.h" and "pgtable-3level-types.h"
Need include "asm/types.h", just like arm has done, or can not pass
compiling, the related error:

  In file included from arch/arm64/include/asm/page.h:37:0,
                   from drivers/staging/lustre/include/linux/lnet/linux/lib-lnet.h:42,
                   from drivers/staging/lustre/include/linux/lnet/lib-lnet.h:44,
                   from drivers/staging/lustre/lnet/lnet/api-ni.c:38:
  arch/arm64/include/asm/pgtable-2level-types.h:19:1: error: unknown type name ‘u64
  arch/arm64/include/asm/pgtable-2level-types.h:20:1: error: unknown type name ‘u64’

Signed-off-by: Chen Gang <gang.chen@asianux.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 360b35a874)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 19:59:55 +01:00
Santosh Shilimkar
9a87b8d3cd of: Specify initrd location using 64-bit
On some PAE architectures, the entire range of physical memory could reside
outside the 32-bit limit.  These systems need the ability to specify the
initrd location using 64-bit numbers.

This patch globally modifies the early_init_dt_setup_initrd_arch() function to
use 64-bit numbers instead of the current unsigned long.

There has been quite a bit of debate about whether to use u64 or phys_addr_t.
It was concluded to stick to u64 to be consistent with rest of the device
tree code. As summarized by Geert, "The address to load the initrd is decided
by the bootloader/user and set at that point later in time. The dtb should not
be tied to the kernel you are booting"

More details on the discussion can be found here:
https://lkml.org/lkml/2013/6/20/690
https://lkml.org/lkml/2012/9/13/544

Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
(cherry picked from commit 374d5c9964)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 19:59:55 +01:00
Chen Gang
c0d0b7ddd1 arm64: add '#ifdef CONFIG_COMPAT' for aarch32_break_handler()
If 'COMPAT' not defined, aarch32_break_handler() cannot pass compiling,
and it can work independent with 'COMPAT', so remove dummy definition.

The related error:

  arch/arm64/kernel/debug-monitors.c:249:5: error: redefinition of ‘aarch32_break_handler’
  In file included from arch/arm64/kernel/debug-monitors.c:29:0:
  /root/linux-next/arch/arm64/include/asm/debug-monitors.h:89:12: note: previous definition of ‘aarch32_break_handler’ was here

Signed-off-by: Chen Gang <gang.chen@asianux.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit c783c2815e)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 19:59:55 +01:00
Vinayak Kale
eadf099dfa arm64: Add initial DTS for APM X-Gene Storm SOC and APM Mustang board
This patch adds initial DTS files required for APM Mustang board.

Signed-off-by: Kumar Sankaran <ksankaran@apm.com>
Signed-off-by: Loc Ho <lho@apm.com>
Signed-off-by: Feng Kan <fkan@apm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit ee877b5321)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 19:59:55 +01:00
Vinayak Kale
63442c002f arm64: Add defines for APM ARMv8 implementation
This patch adds defines for APM CPU implementer ID and APM CPU part numbers in asm/cputype.h

Signed-off-by: Kumar Sankaran <ksankaran@apm.com>
Signed-off-by: Loc Ho <lho@apm.com>
Signed-off-by: Feng Kan <fkan@apm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 4ad637a452)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 19:59:54 +01:00
Vinayak Kale
4e7b7c9c2a arm64: Enable APM X-Gene SOC family in the defconfig
This patch enables APM X-Gene SOC family in the defconfig. It also enables 8250 serial driver needed by X-Gene SOC family.

Signed-off-by: Kumar Sankaran <ksankaran@apm.com>
Signed-off-by: Loc Ho <lho@apm.com>
Signed-off-by: Feng Kan <fkan@apm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit c1db16dc9e)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 19:59:54 +01:00
Vinayak Kale
a9439270f9 arm64: Add Kconfig option for APM X-Gene SOC family
This patch adds arm64/Kconfig option for APM X-Gene SOC family.

Signed-off-by: Kumar Sankaran <ksankaran@apm.com>
Signed-off-by: Loc Ho <lho@apm.com>
Signed-off-by: Feng Kan <fkan@apm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 1594285383)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 19:59:54 +01:00
Kyle McMartin
a8ed08a5da arm64/Makefile: provide vdso_install target
Provide a vdso_install target in the arm64 Makefile, as other architectures
with a vdso do.

Signed-off-by: Kyle McMartin <kyle@redhat.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 3c01742a8a)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 19:59:53 +01:00
Will Deacon
9377422c5c arm64: debug: consolidate software breakpoint handlers
The software breakpoint handlers are hooked in directly from ptrace,
which makes it difficult to add additional handlers for things like
kprobes and kgdb.

This patch moves the handling code into debug-monitors.c, where we can
dispatch to different debug subsystems more easily.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 1442b6ed24)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 19:59:53 +01:00
Will Deacon
dc1307d294 arm64: extable: sort the exception table at build time
As is done for other architectures, sort the exception table at
build-time rather than during boot.

Since sortextable appears to be a standalone C program relying on the
host elf.h to provide EM_AARCH64, I've had to add a conditional check in
order to allow cross-compilation on machines that aren't running a
bleeding-edge libc-dev.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit adace89562)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 19:59:53 +01:00
Will Deacon
179e79828c arm64: device: add iommu pointer to device archdata
When using an IOMMU for device mappings, it is necessary to keep a
pointer between the device and the IOMMU to which it is attached in
order to obtain the correct IOMMU when attaching the device to a domain.

This patch adds an iommu pointer to the dev_archdata structure, in a
similar manner to other architectures (ARM, PowerPC, x86, ...).

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 73150c983a)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 19:59:53 +01:00
Will Deacon
712bda65b9 arm64: pgtable: use pte_index instead of __pte_index
pte_index is a useful helper outside of arch/arm64, for things like the
ARM SMMU driver, so rename __pte_index to pte_index to be consistent
with both arch/arm/ and also the definitions of pmd_index and pgd_index.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 9ab6d02fdd)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 19:59:52 +01:00
Chen Gang
b1793a1874 arm64: kernel: compiling issue, need delete read_current_timer()
Under arm64, we will calibrate the delay loop statically using a known
timer frequency, so delete read_current_timer(), or it will cause
compiling issue with allmodconfig.

The related error:
  ERROR: "read_current_timer" [lib/rbtree_test.ko] undefined!
  ERROR: "read_current_timer" [lib/interval_tree_test.ko] undefined!
  ERROR: "read_current_timer" [fs/ext4/ext4.ko] undefined!
  ERROR: "read_current_timer" [crypto/tcrypt.ko] undefined!

Signed-off-by: Chen Gang <gang.chen@asianux.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 6916b14ea1)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 19:59:52 +01:00
Will Deacon
f81685d080 arm64: mm: don't bother invalidating the icache in switch_mm
We don't support software broadcast of cache maintenance operations, so
this flush is not required (__sync_icache_dcache will always affect all
CPUs).

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 737c16dffc)
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 19:59:52 +01:00
Mark Brown
ae41944bea arm64: Fix build for __PAGE_NONE define
Simple typo.

Signed-off-by: Mark Brown <broonie@linaro.org>
2014-05-15 19:59:52 +01:00
Steve Capper
2457c2704c arm64: mm: Add double logical invert to pte accessors
Page table entries on ARM64 are 64 bits, and some pte functions such as
pte_dirty return a bitwise-and of a flag with the pte value. If the
flag to be tested resides in the upper 32 bits of the pte, then we run
into the danger of the result being dropped if downcast.

For example:
	gather_stats(page, md, pte_dirty(*pte), 1);
where pte_dirty(*pte) is downcast to an int.

This patch adds a double logical invert to all the pte_ accessors to
ensure predictable downcasting.

Signed-off-by: Steve Capper <steve.capper@linaro.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-05-15 19:59:51 +01:00
Steve Capper
2f4620f7ab arm64: mm: Introduce PTE_WRITE
We have the following means for encoding writable or dirty ptes:

                                PTE_DIRTY       PTE_RDONLY
!pte_dirty && !pte_write        0               1
!pte_dirty && pte_write         0               1
pte_dirty && !pte_write         1               1
pte_dirty && pte_write          1               0

So we can't distinguish between writable clean ptes and read only
ptes. This can cause problems with ptes being incorrectly flagged as
read only when they are writable but not dirty.

This patch introduces a new software bit PTE_WRITE which allows us to
correctly identify writable ptes. PTE_RDONLY is now only clear for
valid ptes where a page is both writable and dirty.

Signed-off-by: Steve Capper <steve.capper@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

Conflicts:
	arch/arm64/include/asm/pgtable.h
2014-05-15 19:59:51 +01:00
Steve Capper
9370103e56 arm64: mm: Remove PTE_BIT_FUNC macro
Expand out the pte manipulation functions. This makes our life easier
when using things like tags and cscope.

Signed-off-by: Steve Capper <steve.capper@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-05-15 19:59:51 +01:00
Andreas Sandberg
d5edd6d254 mm/hugetlb.c: call MMU notifiers when copying a hugetlb page range
When copy_hugetlb_page_range() is called to copy a range of hugetlb
mappings, the secondary MMUs are not notified if there is a protection
downgrade, which breaks COW semantics in KVM.

This patch adds the necessary MMU notifier calls.

Signed-off-by: Andreas Sandberg <andreas@sandberg.pp.se>
Acked-by: Steve Capper <steve.capper@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-05-15 19:59:50 +01:00
Steve Capper
ce30e7d5f7 arm64: mm: Fix PMD_SECT_PROT_NONE definition
Modify the value of PMD_SECT_PROT_NONE to match that of PTE_NONE. This
should have been in commit 3676f9ef54 (Move PTE_PROT_NONE higher up).

Signed-off-by: Steve Capper <steve.capper@linaro.org>
Cc: <stable@vger.kernel.org> # 3.11+: 3676f9ef54: arm64: Move PTE_PROT_NONE higher up
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-05-15 19:59:50 +01:00
Catalin Marinas
6d9c4ff8c2 arm64: Move PTE_PROT_NONE higher up
PTE_PROT_NONE means that a pte is present but does not have any
read/write attributes. However, setting the memory type like
pgprot_writecombine() is allowed and such bits overlap with
PTE_PROT_NONE. This causes mmap/munmap issues in drivers that change the
vma->vm_pg_prot on PROT_NONE mappings.

This patch reverts the PTE_FILE/PTE_PROT_NONE shift in commit
59911ca432 (ARM64: mm: Move PTE_PROT_NONE bit) and moves PTE_PROT_NONE
together with the other software bits.

Signed-off-by: Steve Capper <steve.capper@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Steve Capper <steve.capper@linaro.org>
Cc: <stable@vger.kernel.org> # 3.11+
2014-05-15 19:59:50 +01:00
Steve Capper
d9ccf6b164 ARM64: mm: THP support.
Bring Transparent HugePage support to ARM. The size of a
transparent huge page depends on the normal page size. A
transparent huge page is always represented as a pmd.

If PAGE_SIZE is 4KB, THPs are 2MB.
If PAGE_SIZE is 64KB, THPs are 512MB.

Signed-off-by: Steve Capper <steve.capper@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
2014-05-15 19:59:50 +01:00
Steve Capper
00d9acb137 ARM64: mm: Raise MAX_ORDER for 64KB pages and THP.
The buddy allocator has a default MAX_ORDER of 11, which is too
low to allocate enough memory for 512MB Transparent HugePages if
our base page size is 64KB.

This patch introduces MAX_ZONE_ORDER and sets it to 14 when 64KB
pages are used in conjuction with THP, otherwise the default value
of 11 is used.

Signed-off-by: Steve Capper <steve.capper@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
2014-05-15 19:59:49 +01:00
Steve Capper
3b5a3a6a37 ARM64: mm: HugeTLB support.
Add huge page support to ARM64, different huge page sizes are
supported depending on the size of normal pages:

PAGE_SIZE is 4KB:
   2MB - (pmds) these can be allocated at any time.
1024MB - (puds) usually allocated on bootup with the command line
         with something like: hugepagesz=1G hugepages=6

PAGE_SIZE is 64KB:
 512MB - (pmds) usually allocated on bootup via command line.

Signed-off-by: Steve Capper <steve.capper@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
2014-05-15 19:59:49 +01:00
Steve Capper
d2ddf5c863 ARM64: mm: Move PTE_PROT_NONE bit.
Under ARM64, PTEs can be broadly categorised as follows:
   - Present and valid: Bit #0 is set. The PTE is valid and memory
     access to the region may fault.

   - Present and invalid: Bit #0 is clear and bit #1 is set.
     Represents present memory with PROT_NONE protection. The PTE
     is an invalid entry, and the user fault handler will raise a
     SIGSEGV.

   - Not present (file or swap): Bits #0 and #1 are clear.
     Memory represented has been paged out. The PTE is an invalid
     entry, and the fault handler will try and re-populate the
     memory where necessary.

Huge PTEs are block descriptors that have bit #1 clear. If we wish
to represent PROT_NONE huge PTEs we then run into a problem as
there is no way to distinguish between regular and huge PTEs if we
set bit #1.

To resolve this ambiguity this patch moves PTE_PROT_NONE from
bit #1 to bit #2 and moves PTE_FILE from bit #2 to bit #3. The
number of swap/file bits is reduced by 1 as a consequence, leaving
60 bits for file and swap entries.

Signed-off-by: Steve Capper <steve.capper@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
2014-05-15 19:59:49 +01:00
Steve Capper
9bdb6ff441 ARM64: mm: Make PAGE_NONE pages read only and no-execute.
If we consider the following code sequence:

	my_pte = pte_modify(entry, myprot);
	x = pte_write(my_pte);
	y = pte_exec(my_pte);

If myprot comes from a PROT_NONE page, then x and y will both be
true which is undesireable behaviour.

This patch sets the no-execute and read-only bits for PAGE_NONE
such that the code above will return false for both x and y.

Signed-off-by: Steve Capper <steve.capper@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
2014-05-15 19:59:48 +01:00
Steve Capper
bf966f2702 ARM64: mm: Restore memblock limit when map_mem finished.
In paging_init the memblock limit is set to restrict any addresses
returned by early_alloc to fit within the initial direct kernel
mapping in swapper_pg_dir. This allows map_mem to allocate puds,
pmds and ptes from the initial direct kernel mapping.

The limit stays low after paging_init() though, meaning any
bootmem allocations will be from a restricted subset of memory.
Gigabyte huge pages, for instance, are normally allocated from
bootmem as their order (18) is too large for the default buddy
allocator (MAX_ORDER = 11).

This patch restores the memblock limit when map_mem has finished,
allowing gigabyte huge pages (and other objects) to be allocated
from all of bootmem.

Signed-off-by: Steve Capper <steve.capper@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
2014-05-15 19:59:48 +01:00
Steve Capper
6991fe93fc mm: thp: Correct the HPAGE_PMD_ORDER check.
All Transparent Huge Pages are allocated by the buddy allocator.

A compile time check is in place that fails when the order of a
transparent huge page is too large to be allocated by the buddy
allocator. Unfortunately that compile time check passes when:
HPAGE_PMD_ORDER == MAX_ORDER
( which is incorrect as the buddy allocator can only allocate
memory of order strictly less than MAX_ORDER. )

This patch updates the compile time check to fail in the above
case.

Signed-off-by: Steve Capper <steve.capper@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
2014-05-15 19:59:48 +01:00