This affects certain 4Kc cores.
Signed-off-by: NDouglas Leung <douglas@mips.com>
Signed-off-by: NSteven J. Hill <sjhill@mips.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3855/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Remove usage of the '__attribute__((alias("...")))' hack that aliased
to integer arrays containing micro-assembled instructions. This hack
breaks when building a microMIPS kernel. It also makes the code much
easier to understand.

[ralf@linux-mips.org: Added back export of the clear_page and copy_page
symbols so certain modules will work again.  Also fixed build with
CONFIG_SIBYTE_DMA_PAGEOPS enabled.]
Signed-off-by: NSteven J. Hill <sjhill@mips.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3866/Acked-by: NDavid Daney <david.daney@cavium.com>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

[ralf@linux-mips.org: Fixed whitespace damage.]
Signed-off-by: NSteven J. Hill <sjhill@mips.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3773/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NDavid Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3821/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NDavid Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3820/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This has been obsolescent for a while; time for the final push.

In adjacent context, replaced old cpus_* with cpumask_*.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Acked-by: David S. Miller <davem@davemloft.net> (arch/sparc)
Acked-by: Chris Metcalf <cmetcalf@tilera.com> (arch/tile)
Cc: user-mode-linux-devel@lists.sourceforge.net
Cc: Russell King <linux@arm.linux.org.uk>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: linux-hexagon@vger.kernel.org
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Helge Deller <deller@gmx.de>
Cc: sparclinux@vger.kernel.org

Disintegrate asm/system.h for MIPS.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Acked-by: NRalf Baechle <ralf@linux-mips.org>
cc: linux-mips@linux-mips.org

Adapt core MIPS architecture code for dma_map_ops changes: replace
alloc/free_coherent with generic alloc/free methods.
Signed-off-by: NAndrzej Pietrasiewicz <andrzej.p@samsung.com>
Acked-by: NKyungmin Park <kyungmin.park@samsung.com>
[added missing changes to arch/mips/cavium-octeon/dma-octeon.c,
 fixed attrs argument in dma-mapping.h]
Signed-off-by: NMarek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: NArnd Bergmann <arnd@arndb.de>

[swarren@nvidia.com: highmem: Fix ARM build break due to __kmap_atomic rename]
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NCong Wang <amwang@redhat.com>

Signed-off-by: NCong Wang <amwang@redhat.com>

Commit d065bd81
(mm: retry page fault when blocking on disk transfer) and
commit 37b23e05
(x86,mm: make pagefault killable)

The above commits introduced changes into the x86 pagefault handler
for making the page fault handler retryable as well as killable.

These changes reduce the mmap_sem hold time, which is crucial
during OOM killer invocation.

Port these changes to MIPS.

Without these changes, my MIPS board encounters many hang and livelock
scenarios.
After applying this patch, OOM feature performance improves according to
my testing.
Signed-off-by: NMohd. Faris <mohdfarisq2010@gmail.com>
Signed-off-by: NKautuk Consul <consul.kautuk@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/3217/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Only available for R4000 style TLBs anyway and proper ordering of
initialization code made this crude interface unncecessary.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

When flushing TLB, if @vma is backed by huge page, we could flush huge
TLB, due to that huge page is defined to be far from normal page.
Signed-off-by: NHillf Danton <dhillf@gmail.com>
Acked-by: NDavid Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: "Jayachandran C." <jayachandranc@netlogicmicro.com>
Patchwork: https://patchwork.linux-mips.org/patch/2825/Signed-off-by: NDavid Daney <david.daney@cavium.com>
Acked-by: NHillf Danton <dhillf@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/3114/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

- Add CPU_XLP and NLM_XLR_BOARD to arch/mips/Kconfig for Netlogic XLP boards
- Update mips Makefiles to add XLP
Signed-off-by: NJayachandran C <jayachandranc@netlogicmicro.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2968/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Add support for Netlogic's XLP MIPS SoC. This patch adds:
* XLP processor ID in cpu_probe.c and asm/cpu.h
* XLP case to asm/module.h
* CPU_XLP case to mm/tlbex.c
* minor change to r4k cache handling to ignore XLP secondary cache
* XLP cpu overrides to mach-netlogic/cpu-feature-overrides.h
Signed-off-by: NJayachandran C <jayachandranc@netlogicmicro.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2966/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This patch addresses a couple of related problems:

1) The kernel may reside in physical memory outside of the ranges set
   by plat_mem_setup().  If this is the case, init mem cannot be
   reused as it resides outside of the range of pages that the kernel
   memory allocators control.

2) initrd images might be loaded in physical memory outside of the
   ranges set by plat_mem_setup().  The memory likewise cannot be
   reused.  The patch doesn't handle this specific case, but the
   infrastructure is useful for future patches that do.

The crux of the problem is that there are memory regions that need be
memory_present(), but that cannot be free_bootmem() at the time of
arch_mem_init().  We create a new type of memory (BOOT_MEM_INIT_RAM)
for use with add_memory_region().  Then arch_mem_init() adds the init
mem with this type if the init mem is not already covered by existing
ranges.

When memory is being freed into the bootmem allocator, we skip the
BOOT_MEM_INIT_RAM ranges so they are not clobbered, but we do signal
them as memory_present().  This way when they are later freed, the
necessary memory manager structures have initialized and the Sparse
allocater is prevented from crashing.

The Octeon specific code that handled this case is removed, because
the new general purpose code handles the case.
Signed-off-by: NDavid Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1988/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Gup is used in a few cases, say futex.

This work is derived from the x86 version, and operations of pte and pmd are
adapted to the defines of MIPS in straight forward manner.

[ralf@linux-mips.org: Fixed up reject in arch/mips/mm/Makefile due to
whitespace formatting differences.  Fixed build error in gup.c due to
conflicting changes elsewhere in the kernel.]
Signed-off-by: NHillf Danton <dhillf@gmail.com>
Cc: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2859/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Move add_wired_entry to its own header file from where it will be
always included.  Patch up other users of add_wired_entry to also include
the header as needed.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Panic() invokes printk() to add a \n internally, so panic arguments should
not themselves end in \n.  Panic invocations in arch/mips and elsewhere
are inconsistently sometimes terminating in \n, sometimes not.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

For Alchemy-PCI I need to add a wired entry after resuming from RAM;
remove the __init from add_wired_entry() so that this actually works.
Signed-off-by: NManuel Lauss <manuel.lauss@googlemail.com>
To: Linux-MIPS <linux-mips@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/2684/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Until now flush_kernel_vmap_range() and invalidate_kernel_vmap_range() did
not exist on MIPS resulting in heavy cache corruption on XFS filesystems.

Left for the post-3.0 time: optimization and make this work with highmem,
too.  Since the combination of highmem + cache aliases atm doesn't work
this isn't a regression.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/2505/

For the case PM_DEFAULT_MASK == 0, we were placing a branch in the
delay slot of another branch.  This leads to undefined behavior.
Signed-off-by: NDavid Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2775/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Only some GCC versions such as gcc 4.2 notice that the variable wr in
build_r3000_tlb_modify_handler is used uninitialized.  When using one
of those GCCs the build will fail due to -Werror.  GCC 4.6 does not
warn about the uninitialized use of wr.

This issue was introduced by 7211f4d7a3dcbe57c5d396c334dca525315dceb2
[MIPS: Close races in TLB modify handlers.]
Reported-by: NGanesan Ramalingam <ganesan18@gmail.com>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Fix checkpatch warnings.  Rename arch_get_unmapped_area_foo() to
arch_get_unmapped_area_common().  Make indentations and spacing more
consistent.  Add <linux/compiler.h> for likely/unlikely.
Signed-off-by: NKevin Cernekee <cernekee@gmail.com>
Cc: Jian Peng <jipeng2005@gmail.com>
Cc: David Daney <ddaney@caviumnetworks.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2506/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Page table entries are made invalid by writing a zero into the the PTE
slot in a page table.  This creates a race condition with the TLB
modify handlers when they are updating the PTE.

CPU0                              CPU1

Test for _PAGE_PRESENT
.                                 set to not _PAGE_PRESENT (zero)
Set to _PAGE_VALID

So now the page not present value (zero) is suddenly valid and user
space programs have access to physical page zero.

We close the race by putting the test for _PAGE_PRESENT and setting of
_PAGE_VALID into an atomic LL/SC section.  This requires more registers
than just K0 and K1 in the handlers, so we need to save some registers
to a save area and then restore them when we are done.

The save area is an array of cacheline aligned structures that should
not suffer cache line bouncing as they are CPU private.

[ralf@linux-mips.org: Fix !defined(CONFIG_MIPS_PGD_C0_CONTEXT) build error.]
Signed-off-by: NDavid Daney <david.daney@cavium.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2577/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

fixrange_init() allocates page tables for all addresses higher than
FIXADDR_TOP.  On processors that override the default FIXADDR_TOP
address of 0xfffe_0000, this can consume up to 4 pages (1 page per 4MB)
for pgd's that are never used.
Signed-off-by: NKevin Cernekee <cernekee@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/1980/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

On processors with deep write buffers, it is likely that many cycles
will pass between a CACHE instruction and the time the data actually
gets written out to DRAM.  Add a SYNC instruction to ensure that the
buffers get emptied before the flush functions return.

Actual problem seen in the wild:

1) dma_alloc_coherent() allocates cached memory

2) memset() is called to clear the new pages

3) dma_cache_wback_inv() is called to flush the zero data out to memory

4) dma_alloc_coherent() returns an uncached (kseg1) pointer to the
freshly allocated pages

5) Caller writes data through the kseg1 pointer

6) Buffered writeback data finally gets flushed out to DRAM

7) Part of caller's data is inexplicably zeroed out

This patch adds SYNC between steps 3 and 4, which fixed the problem.
Signed-off-by: NKevin Cernekee <cernekee@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: 
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

pfn_valid() compares the PFN to max_mapnr:

        __pfn >= min_low_pfn && __pfn < max_mapnr;

On HIGHMEM kernels, highend_pfn is used to set the value of max_mapnr.
Unfortunately, highend_pfn is left at zero if the system does not
actually have enough RAM to reach into the HIGHMEM range.  This causes
pfn_valid() to always return false, and when debug checks are enabled
the kernel will fail catastrophically:

Memory: 22432k/32768k available (2249k kernel code, 10336k reserved, 653k data, 1352k init, 0k highmem)
NR_IRQS:128
kfree_debugcheck: out of range ptr 81c02900h.
Kernel bug detected[#1]:
Cpu 0
$ 0   : 00000000 10008400 00000034 00000000
$ 4   : 8003e160 802a0000 8003e160 00000000
$ 8   : 00000000 0000003e 00000747 00000747
...

On such a configuration, max_low_pfn should be used to set max_mapnr.

This was seen on 2.6.34.
Signed-off-by: NKevin Cernekee <cernekee@gmail.com>
To: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/1992/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

[v4: Patch applies to linux-queue.git with kmap_atomic patches:
 https://patchwork.kernel.org/patch/189932/
 https://patchwork.kernel.org/patch/194552/
 https://patchwork.kernel.org/patch/189912/ ]

The MIPS DMA coherency functions do not work properly (i.e. kernel oops)
when HIGHMEM pages are passed in as arguments.  Use kmap_atomic() to
temporarily map high pages for cache maintenance operations.

Tested on a 2.6.36-rc7 1GB HIGHMEM SMP no-alias system.
Signed-off-by: NDezhong Diao <dediao@cisco.com>
Signed-off-by: NKevin Cernekee <cernekee@gmail.com>
Cc: Dezhong Diao <dediao@cisco.com>
Cc: David Daney <ddaney@caviumnetworks.com>
Cc: David VomLehn <dvomlehn@cisco.com>
Cc: Sergei Shtylyov <sshtylyov@mvista.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/1695/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This patch introduced topdown mmap support in user process address
space allocation policy.

Recently, we ran some large applications that use mmap heavily and
lead to OOM due to inflexible mmap allocation policy on MIPS32.

Since most other major archs supported it for years, it is reasonable
to follow the trend and reduce the pain of porting applications.

Due to cache aliasing concern, arch_get_unmapped_area_topdown() and
other helper functions are implemented in arch/mips/kernel/syscall.c.
Signed-off-by: NJian Peng <jipeng2005@gmail.com>
Cc: David Daney <ddaney@caviumnetworks.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2389/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The nmi parameter indicated if we could do wakeups from the current
context, if not, we would set some state and self-IPI and let the
resulting interrupt do the wakeup.

For the various event classes:

  - hardware: nmi=0; PMI is in fact an NMI or we run irq_work_run from
    the PMI-tail (ARM etc.)
  - tracepoint: nmi=0; since tracepoint could be from NMI context.
  - software: nmi=[0,1]; some, like the schedule thing cannot
    perform wakeups, and hence need 0.

As one can see, there is very little nmi=1 usage, and the down-side of
not using it is that on some platforms some software events can have a
jiffy delay in wakeup (when arch_irq_work_raise isn't implemented).

The up-side however is that we can remove the nmi parameter and save a
bunch of conditionals in fast paths.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Michael Cree <mcree@orcon.net.nz>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Deng-Cheng Zhu <dengcheng.zhu@gmail.com>
Cc: Anton Blanchard <anton@samba.org>
Cc: Eric B Munson <emunson@mgebm.net>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Don Zickus <dzickus@redhat.com>
Link: http://lkml.kernel.org/n/tip-agjev8eu666tvknpb3iaj0fg@git.kernel.orgSigned-off-by: NIngo Molnar <mingo@elte.hu>

Fold all the mmu_gather rework patches into one for submission
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Reported-by: NHugh Dickins <hughd@google.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Miller <davem@davemloft.net>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Tony Luck <tony.luck@intel.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

It never really belonged into syscall.c and it's about to become well more
complex.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Add NLM_XLR_BOARD, CPU_XLR and other config options
Makefile updates, mostly based on r4k
Signed-off-by: NJayachandran C <jayachandranc@netlogicmicro.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2334/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

CPU_XLR case added to mm/tlbex.c
CPU_XLR case added to mm/c-r4k.c for PINDEX attribute
Feature overrides for XLR cpu.
Signed-off-by: NJayachandran C <jayachandranc@netlogicmicro.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2333/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

  CC      arch/mips/mm/tlbex.o
arch/mips/mm/tlbex.c: In function 'build_r4000_tlb_refill_handler':
arch/mips/mm/tlbex.c:1155:22: error: variable 'vmalloc_mode' set but not used [-Werror=unused-but-set-variable]
arch/mips/mm/tlbex.c:1154:28: error: variable 'htlb_info' set but not used [-Werror=unused-but-set-variable]
cc1: all warnings being treated as errors
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

  CC      arch/mips/mm/c-r4k.o
arch/mips/mm/c-r4k.c: In function 'probe_scache':
arch/mips/mm/c-r4k.c:1078:6: error: variable 'tmp' set but not used [-Werror=unused-but-set-variable]
cc1: all warnings being treated as errors

Older GCC versions didn't warn about the unused variable tmp because it was
getting initialized.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NJustin P. Mattock <justinmattock@gmail.com>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Fixes generated by 'codespell' and manually reviewed.
Signed-off-by: NLucas De Marchi <lucas.demarchi@profusion.mobi>

Under some combinations of CONFIG_*, lastpfn in page_is_ram is 'set
but not used'.  Mark it as __maybe_unused to quiet the warning/error.
Signed-off-by: NDavid Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2033/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>