808 Commits

Author SHA1 Message Date
Nathan Chancellor
5134b0a196 MIPS: tlbex: Explicitly compare _PAGE_NO_EXEC against 0
[ Upstream commit 74de14fe05dd6b151d73cb0c73c8ec874cbdcde6 ]

When CONFIG_XPA is enabled, Clang warns:

  arch/mips/mm/tlbex.c:629:24: error: converting the result of '<<' to a boolean; did you mean '(1 << _PAGE_NO_EXEC_SHIFT) != 0'? [-Werror,-Wint-in-bool-context]
          if (cpu_has_rixi && !!_PAGE_NO_EXEC) {
                              ^
  arch/mips/include/asm/pgtable-bits.h:174:28: note: expanded from macro '_PAGE_NO_EXEC'
  # define _PAGE_NO_EXEC          (1 << _PAGE_NO_EXEC_SHIFT)
                                     ^
  arch/mips/mm/tlbex.c:2568:24: error: converting the result of '<<' to a boolean; did you mean '(1 << _PAGE_NO_EXEC_SHIFT) != 0'? [-Werror,-Wint-in-bool-context]
          if (!cpu_has_rixi || !_PAGE_NO_EXEC) {
                                ^
  arch/mips/include/asm/pgtable-bits.h:174:28: note: expanded from macro '_PAGE_NO_EXEC'
  # define _PAGE_NO_EXEC          (1 << _PAGE_NO_EXEC_SHIFT)
                                     ^
  2 errors generated.

_PAGE_NO_EXEC can be '0' or '1 << _PAGE_NO_EXEC_SHIFT' depending on the
build and runtime configuration, which is what the negation operators
are trying to convey. To silence the warning, explicitly compare against
0 so the result of the '<<' operator is not implicitly converted to a
boolean.

According to its documentation, GCC enables -Wint-in-bool-context with
-Wall but this warning is not visible when building the same
configuration with GCC. It appears GCC only warns when compiling C++,
not C, although the documentation makes no note of this:
https://godbolt.org/z/x39q3brxf

Reported-by: Sudip Mukherjee (Codethink) <sudipm.mukherjee@gmail.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-25 11:09:32 +02:00
Linus Torvalds
0c29640bde gup: document and work around "COW can break either way" issue
commit 9bbd42e79720122334226afad9ddcac1c3e6d373 upstream.

Doing a "get_user_pages()" on a copy-on-write page for reading can be
ambiguous: the page can be COW'ed at any time afterwards, and the
direction of a COW event isn't defined.

Yes, whoever writes to it will generally do the COW, but if the thread
that did the get_user_pages() unmapped the page before the write (and
that could happen due to memory pressure in addition to any outright
action), the writer could also just take over the old page instead.

End result: the get_user_pages() call might result in a page pointer
that is no longer associated with the original VM, and is associated
with - and controlled by - another VM having taken it over instead.

So when doing a get_user_pages() on a COW mapping, the only really safe
thing to do would be to break the COW when getting the page, even when
only getting it for reading.

At the same time, some users simply don't even care.

For example, the perf code wants to look up the page not because it
cares about the page, but because the code simply wants to look up the
physical address of the access for informational purposes, and doesn't
really care about races when a page might be unmapped and remapped
elsewhere.

This adds logic to force a COW event by setting FOLL_WRITE on any
copy-on-write mapping when FOLL_GET (or FOLL_PIN) is used to get a page
pointer as a result.

The current semantics end up being:

 - __get_user_pages_fast(): no change. If you don't ask for a write,
   you won't break COW. You'd better know what you're doing.

 - get_user_pages_fast(): the fast-case "look it up in the page tables
   without anything getting mmap_sem" now refuses to follow a read-only
   page, since it might need COW breaking.  Which happens in the slow
   path - the fast path doesn't know if the memory might be COW or not.

 - get_user_pages() (including the slow-path fallback for gup_fast()):
   for a COW mapping, turn on FOLL_WRITE for FOLL_GET/FOLL_PIN, with
   very similar semantics to FOLL_FORCE.

If it turns out that we want finer granularity (ie "only break COW when
it might actually matter" - things like the zero page are special and
don't need to be broken) we might need to push these semantics deeper
into the lookup fault path.  So if people care enough, it's possible
that we might end up adding a new internal FOLL_BREAK_COW flag to go
with the internal FOLL_COW flag we already have for tracking "I had a
COW".

Alternatively, if it turns out that different callers might want to
explicitly control the forced COW break behavior, we might even want to
make such a flag visible to the users of get_user_pages() instead of
using the above default semantics.

But for now, this is mostly commentary on the issue (this commit message
being a lot bigger than the patch, and that patch in turn is almost all
comments), with that minimal "enable COW breaking early" logic using the
existing FOLL_WRITE behavior.

[ It might be worth noting that we've always had this ambiguity, and it
  could arguably be seen as a user-space issue.

  You only get private COW mappings that could break either way in
  situations where user space is doing cooperative things (ie fork()
  before an execve() etc), but it _is_ surprising and very subtle, and
  fork() is supposed to give you independent address spaces.

  So let's treat this as a kernel issue and make the semantics of
  get_user_pages() easier to understand. Note that obviously a true
  shared mapping will still get a page that can change under us, so this
  does _not_ mean that get_user_pages() somehow returns any "stable"
  page ]

[surenb: backport notes
	Replaced (gup_flags | FOLL_WRITE) with write=1 in gup_pgd_range.
	Removed FOLL_PIN usage in should_force_cow_break since it's missing in
	the earlier kernels.]

Reported-by: Jann Horn <jannh@google.com>
Tested-by: Christoph Hellwig <hch@lst.de>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Kirill Shutemov <kirill@shutemov.name>
Acked-by: Jan Kara <jack@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[surenb: backport to 4.19 kernel]
Cc: stable@vger.kernel.org # 4.19.x
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 4.9:
 - Generic get_user_pages_fast() calls __get_user_pages_fast() here,
   so make it pass write=1
 - Various architectures have their own implementations of
   get_user_pages_fast(), so apply the corresponding change there
 - Adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-27 08:47:42 +01:00
Nathan Chancellor
a1371240c8 MIPS: c-r4k: Fix section mismatch for loongson2_sc_init
[ Upstream commit c58734eee6a2151ba033c0dcb31902c89e310374 ]

When building with clang, the following section mismatch warning occurs:

WARNING: modpost: vmlinux.o(.text+0x24490): Section mismatch in
reference from the function r4k_cache_init() to the function
.init.text:loongson2_sc_init()

This should have been fixed with commit ad4fddef5f23 ("mips: fix Section
mismatch in reference") but it was missed. Remove the improper __init
annotation like that commit did.

Fixes: 078a55fc824c ("MIPS: Delete __cpuinit/__CPUINIT usage from MIPS code")
Link: https://github.com/ClangBuiltLinux/linux/issues/787
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Huacai Chen <chenhuacai@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-03 17:44:34 +01:00
Randy Dunlap
5f575c174b MIPS: export has_transparent_hugepage() for modules
[ Upstream commit 31b4d8e172f614adc53ddecb4b6b2f6411a49b84 ]

MIPS should export its local version of "has_transparent_hugepage"
so that loadable modules (dax) can use it.

Fixes this build error:
ERROR: modpost: "has_transparent_hugepage" [drivers/dax/dax.ko] undefined!

Fixes: fd8cfd300019 ("arch: fix has_transparent_hugepage()")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: linux-mips@vger.kernel.org
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: linux-nvdimm@lists.01.org
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-11-24 13:03:01 +01:00
Florian Fainelli
334dc5f712 MIPS: mm: BMIPS5000 has inclusive physical caches
[ Upstream commit dbfc95f98f0158958d1f1e6bf06d74be38dbd821 ]

When the BMIPS generic cpu-feature-overrides.h file was introduced,
cpu_has_inclusive_caches/MIPS_CPU_INCLUSIVE_CACHES was not set for
BMIPS5000 CPUs. Correct this when we have initialized the MIPS secondary
cache successfully.

Fixes: f337967d6d87 ("MIPS: BMIPS: Add cpu-feature-overrides.h")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-09-12 11:47:33 +02:00
Paul Burton
bfdf982921 MIPS: tlbex: Fix build_restore_pagemask KScratch restore
commit b42aa3fd5957e4daf4b69129e5ce752a2a53e7d6 upstream.

build_restore_pagemask() will restore the value of register $1/$at when
its restore_scratch argument is non-zero, and aims to do so by filling a
branch delay slot. Commit 0b24cae4d535 ("MIPS: Add missing EHB in mtc0
-> mfc0 sequence.") added an EHB instruction (Execution Hazard Barrier)
prior to restoring $1 from a KScratch register, in order to resolve a
hazard that can result in stale values of the KScratch register being
observed. In particular, P-class CPUs from MIPS with out of order
execution pipelines such as the P5600 & P6600 are affected.

Unfortunately this EHB instruction was inserted in the branch delay slot
causing the MFC0 instruction which performs the restoration to no longer
execute along with the branch. The result is that the $1 register isn't
actually restored, ie. the TLB refill exception handler clobbers it -
which is exactly the problem the EHB is meant to avoid for the P-class
CPUs.

Similarly build_get_pgd_vmalloc() will restore the value of $1/$at when
its mode argument equals refill_scratch, and suffers from the same
problem.

Fix this by in both cases moving the EHB earlier in the emitted code.
There's no reason it needs to immediately precede the MFC0 - it simply
needs to be between the MTC0 & MFC0.

This bug only affects Cavium Octeon systems which use
build_fast_tlb_refill_handler().

Signed-off-by: Paul Burton <paulburton@kernel.org>
Fixes: 0b24cae4d535 ("MIPS: Add missing EHB in mtc0 -> mfc0 sequence.")
Cc: Dmitry Korotin <dkorotin@wavecomp.com>
Cc: stable@vger.kernel.org # v3.15+
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-29 09:15:18 +01:00
Nathan Chancellor
cbc4467d07 MIPS: tlbex: Explicitly cast _PAGE_NO_EXEC to a boolean
[ Upstream commit c59ae0a1055127dd3828a88e111a0db59b254104 ]

clang warns:

arch/mips/mm/tlbex.c:634:19: error: use of logical '&&' with constant
operand [-Werror,-Wconstant-logical-operand]
        if (cpu_has_rixi && _PAGE_NO_EXEC) {
                         ^  ~~~~~~~~~~~~~
arch/mips/mm/tlbex.c:634:19: note: use '&' for a bitwise operation
        if (cpu_has_rixi && _PAGE_NO_EXEC) {
                         ^~
                         &
arch/mips/mm/tlbex.c:634:19: note: remove constant to silence this
warning
        if (cpu_has_rixi && _PAGE_NO_EXEC) {
                        ~^~~~~~~~~~~~~~~~
1 error generated.

Explicitly cast this value to a boolean so that clang understands we
intend for this to be a non-zero value.

Fixes: 00bf1c691d08 ("MIPS: tlbex: Avoid placing software PTE bits in Entry* PFN fields")
Link: https://github.com/ClangBuiltLinux/linux/issues/609
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: clang-built-linux@googlegroups.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-10-07 18:53:15 +02:00
Dmitry Korotin
dd8f65a719 MIPS: Add missing EHB in mtc0 -> mfc0 sequence.
commit 0b24cae4d535045f4c9e177aa228d4e97bad212c upstream.

Add a missing EHB (Execution Hazard Barrier) in mtc0 -> mfc0 sequence.
Without this execution hazard barrier it's possible for the value read
back from the KScratch register to be the value from before the mtc0.

Reproducible on P5600 & P6600.

The hazard is documented in the MIPS Architecture Reference Manual Vol.
III: MIPS32/microMIPS32 Privileged Resource Architecture (MD00088), rev
6.03 table 8.1 which includes:

   Producer | Consumer | Hazard
  ----------|----------|----------------------------
   mtc0     | mfc0     | any coprocessor 0 register

Signed-off-by: Dmitry Korotin <dkorotin@wavecomp.com>
[paul.burton@mips.com:
  - Commit message tweaks.
  - Add Fixes tags.
  - Mark for stable back to v3.15 where P5600 support was introduced.]
Signed-off-by: Paul Burton <paul.burton@mips.com>
Fixes: 3d8bfdd03072 ("MIPS: Use C0_KScratch (if present) to hold PGD pointer.")
Fixes: 829dcc0a956a ("MIPS: Add MIPS P5600 probe support")
Cc: linux-mips@vger.kernel.org
Cc: stable@vger.kernel.org # v3.15+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-10 09:55:47 +02:00
Paul Burton
8d917cba12 MIPS: WARN_ON invalid DMA cache maintenance, not BUG_ON
[ Upstream commit d4da0e97baea8768b3d66ccef3967bebd50dfc3b ]

If a driver causes DMA cache maintenance with a zero length then we
currently BUG and kill the kernel. As this is a scenario that we may
well be able to recover from, WARN & return in the condition instead.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/14623/
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-19 22:47:16 +02:00
Paul Burton
92cb1184ae MIPS: Fix ioremap() RAM check
commit 523402fa9101090c91d2033b7ebdfdcf65880488 upstream.

We currently attempt to check whether a physical address range provided
to __ioremap() may be in use by the page allocator by examining the
value of PageReserved for each page in the region - lowmem pages not
marked reserved are presumed to be in use by the page allocator, and
requests to ioremap them fail.

The way we check this has been broken since commit 92923ca3aace ("mm:
meminit: only set page reserved in the memblock region"), because
memblock will typically not have any knowledge of non-RAM pages and
therefore those pages will not have the PageReserved flag set. Thus when
we attempt to ioremap a region outside of RAM we incorrectly fail
believing that the region is RAM that may be in use.

In most cases ioremap() on MIPS will take a fast-path to use the
unmapped kseg1 or xkphys virtual address spaces and never hit this path,
so the only way to hit it is for a MIPS32 system to attempt to ioremap()
an address range in lowmem with flags other than _CACHE_UNCACHED.
Perhaps the most straightforward way to do this is using
ioremap_uncached_accelerated(), which is how the problem was discovered.

Fix this by making use of walk_system_ram_range() to test the address
range provided to __ioremap() against only RAM pages, rather than all
lowmem pages. This means that if we have a lowmem I/O region, which is
very common for MIPS systems, we're free to ioremap() address ranges
within it. A nice bonus is that the test is no longer limited to lowmem.

The approach here matches the way x86 performed the same test after
commit c81c8a1eeede ("x86, ioremap: Speed up check for RAM pages") until
x86 moved towards a slightly more complicated check using walk_mem_res()
for unrelated reasons with commit 0e4c12b45aa8 ("x86/mm, resource: Use
PAGE_KERNEL protection for ioremap of memory pages").

Signed-off-by: Paul Burton <paul.burton@mips.com>
Reported-by: Serge Semin <fancer.lancer@gmail.com>
Tested-by: Serge Semin <fancer.lancer@gmail.com>
Fixes: 92923ca3aace ("mm: meminit: only set page reserved in the memblock region")
Cc: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org # v4.2+
Patchwork: https://patchwork.linux-mips.org/patch/19786/
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-17 11:37:51 +02:00
NeilBrown
aa9a00ef3d MIPS: c-r4k: Fix data corruption related to cache coherence
commit 55a2aa08b3af519a9693f99cdf7fa6d8b62d9f65 upstream.

When DMA will be performed to a MIPS32 1004K CPS, the L1-cache for the
range needs to be flushed and invalidated first.
The code currently takes one of two approaches.
1/ If the range is less than the size of the dcache, then HIT type
   requests flush/invalidate cache lines for the particular addresses.
   HIT-type requests a globalised by the CPS so this is safe on SMP.

2/ If the range is larger than the size of dcache, then INDEX type
   requests flush/invalidate the whole cache. INDEX type requests affect
   the local cache only. CPS does not propagate them in any way. So this
   invalidation is not safe on SMP CPS systems.

Data corruption due to '2' can quite easily be demonstrated by
repeatedly "echo 3 > /proc/sys/vm/drop_caches" and then sha1sum a file
that is several times the size of available memory. Dropping caches
means that large contiguous extents (large than dcache) are more likely.

This was not a problem before Linux-4.8 because option 2 was never used
if CONFIG_MIPS_CPS was defined. The commit which removed that apparently
didn't appreciate the full consequence of the change.

We could, in theory, globalize the INDEX based flush by sending an IPI
to other cores. These cache invalidation routines can be called with
interrupts disabled and synchronous IPI require interrupts to be
enabled. Asynchronous IPI may not trigger writeback soon enough. So we
cannot use IPI in practice.

We can already test if IPI would be needed for an INDEX operation with
r4k_op_needs_ipi(R4K_INDEX). If this is true then we mustn't try the
INDEX approach as we cannot use IPI. If this is false (e.g. when there
is only one core and hence one L1 cache) then it is safe to use the
INDEX approach without IPI.

This patch avoids options 2 if r4k_op_needs_ipi(R4K_INDEX), and so
eliminates the corruption.

Fixes: c00ab4896ed5 ("MIPS: Remove cpu_has_safe_index_cacheops")
Signed-off-by: NeilBrown <neil@brown.name>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 4.8+
Patchwork: https://patchwork.linux-mips.org/patch/19259/
Signed-off-by: James Hogan <jhogan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:50:15 +02:00
Marcin Nowakowski
222c8b45a6 MIPS: mm: fixed mappings: correct initialisation
[ Upstream commit 71eb989ab5a110df8bcbb9609bacde73feacbedd ]

fixrange_init operates at PMD-granularity and expects the addresses to
be PMD-size aligned, but currently that might not be the case for
PKMAP_BASE unless it is defined properly, so ensure a correct alignment
is used before passing the address to fixrange_init.

fixed mappings: only align the start address that is passed to
fixrange_init rather than the value before adding the size, as we may
end up with uninitialised upper part of the range.

Signed-off-by: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/15948/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-13 19:48:24 +02:00
Gustavo A. R. Silva
16d5634e88 MIPS: microMIPS: Fix incorrect mask in insn_table_MM
commit 77238e76b9156d28d86c1e31c00ed2960df0e4de upstream.

It seems that this is a typo error and the proper bit masking is
"RT | RS" instead of "RS | RS".

This issue was detected with the help of Coccinelle.

Fixes: d6b3314b49e1 ("MIPS: uasm: Add lh uam instruction")
Reported-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Reviewed-by: James Hogan <jhogan@kernel.org>
Patchwork: https://patchwork.linux-mips.org/patch/17551/
Signed-off-by: James Hogan <jhogan@kernel.org>
[jhogan@kernel.org: Backported 3.16..4.12]
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-15 15:53:18 +01:00
Hugh Dickins
cfc0eb4038 mm: larger stack guard gap, between vmas
commit 1be7107fbe18eed3e319a6c3e83c78254b693acb upstream.

Stack guard page is a useful feature to reduce a risk of stack smashing
into a different mapping. We have been using a single page gap which
is sufficient to prevent having stack adjacent to a different mapping.
But this seems to be insufficient in the light of the stack usage in
userspace. E.g. glibc uses as large as 64kB alloca() in many commonly
used functions. Others use constructs liks gid_t buffer[NGROUPS_MAX]
which is 256kB or stack strings with MAX_ARG_STRLEN.

This will become especially dangerous for suid binaries and the default
no limit for the stack size limit because those applications can be
tricked to consume a large portion of the stack and a single glibc call
could jump over the guard page. These attacks are not theoretical,
unfortunatelly.

Make those attacks less probable by increasing the stack guard gap
to 1MB (on systems with 4k pages; but make it depend on the page size
because systems with larger base pages might cap stack allocations in
the PAGE_SIZE units) which should cover larger alloca() and VLA stack
allocations. It is obviously not a full fix because the problem is
somehow inherent, but it should reduce attack space a lot.

One could argue that the gap size should be configurable from userspace,
but that can be done later when somebody finds that the new 1MB is wrong
for some special case applications.  For now, add a kernel command line
option (stack_guard_gap) to specify the stack gap size (in page units).

Implementation wise, first delete all the old code for stack guard page:
because although we could get away with accounting one extra page in a
stack vma, accounting a larger gap can break userspace - case in point,
a program run with "ulimit -S -v 20000" failed when the 1MB gap was
counted for RLIMIT_AS; similar problems could come with RLIMIT_MLOCK
and strict non-overcommit mode.

Instead of keeping gap inside the stack vma, maintain the stack guard
gap as a gap between vmas: using vm_start_gap() in place of vm_start
(or vm_end_gap() in place of vm_end if VM_GROWSUP) in just those few
places which need to respect the gap - mainly arch_get_unmapped_area(),
and and the vma tree's subtree_gap support for that.

Original-patch-by: Oleg Nesterov <oleg@redhat.com>
Original-patch-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Tested-by: Helge Deller <deller@gmx.de> # parisc
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[wt: backport to 4.11: adjust context]
[wt: backport to 4.9: adjust context ; kernel doc was not in admin-guide]
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-24 07:11:18 +02:00
Huacai Chen
be56f92cc0 MIPS: c-r4k: Fix Loongson-3's vcache/scache waysize calculation
commit 0be032c190abcdcfa948082b6a1e0d461184ba4d upstream.

If scache.waysize is 0, r4k___flush_cache_all() will do nothing and
then cause bugs. BTW, though vcache.waysize isn't being used by now,
we also fix its calculation.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Cc: John Crispin <john@phrozen.org>
Cc: Steven J . Hill <Steven.Hill@caviumnetworks.com>
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/15756/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-12 12:41:15 +02:00
Huacai Chen
59b8725f2b MIPS: Flush wrong invalid FTLB entry for huge page
commit 0115f6cbf26663c86496bc56eeea293f85b77897 upstream.

On VTLB+FTLB platforms (such as Loongson-3A R2), FTLB's pagesize is
usually configured the same as PAGE_SIZE. In such a case, Huge page
entry is not suitable to write in FTLB.

Unfortunately, when a huge page is created, its page table entries
haven't created immediately. Then the TLB refill handler will fetch an
invalid page table entry which has no "HUGE" bit, and this entry may be
written to FTLB. Since it is invalid, TLB load/store handler will then
use tlbwi to write the valid entry at the same place. However, the
valid entry is a huge page entry which isn't suitable for FTLB.

Our solution is to modify build_huge_handler_tail. Flush the invalid
old entry (whether it is in FTLB or VTLB, this is in order to reduce
branches) and use tlbwr to write the valid new entry.

Signed-off-by: Rui Wang <wangr@lemote.com>
Signed-off-by: Huacai Chen <chenhc@lemote.com>
Cc: John Crispin <john@phrozen.org>
Cc: Steven J . Hill <Steven.Hill@caviumnetworks.com>
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/15754/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-12 12:41:14 +02:00
Ralf Baechle
aae02d1aaf MIPS: IP22: Fix build error due to binutils 2.25 uselessnes.
commit ae2f5e5ed04a17c1aa1f0a3714c725e12c21d2a9 upstream.

Fix the following build error with binutils 2.25.

  CC      arch/mips/mm/sc-ip22.o
{standard input}: Assembler messages:
{standard input}:132: Error: number (0x9000000080000000) larger than 32 bits
{standard input}:159: Error: number (0x9000000080000000) larger than 32 bits
{standard input}:200: Error: number (0x9000000080000000) larger than 32 bits
scripts/Makefile.build:293: recipe for target 'arch/mips/mm/sc-ip22.o' failed
make[1]: *** [arch/mips/mm/sc-ip22.o] Error 1

MIPS has used .set mips3 to temporarily switch the assembler to 64 bit
mode in 64 bit kernels virtually forever.  Binutils 2.25 broke this
behavious partially by happily accepting 64 bit instructions in .set mips3
mode but puking on 64 bit constants when generating 32 bit ELF.  Binutils
2.26 restored the old behaviour again.

Fix build with binutils 2.25 by open coding the offending

	dli $1, 0x9000000080000000

as

	li	$1, 0x9000
	dsll	$1, $1, 48

which is ugly be the only thing that will build on all binutils vintages.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-12 06:41:53 +01:00
Ralf Baechle
8a2307c7c0 MIPS: IP22: Reformat inline assembler code to modern standards.
commit f9f1c8db1c37253805eaa32265e1e1af3ae7d0a4 upstream.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-12 06:41:53 +01:00
Matt Redfearn
2a872a5dce MIPS: mm: Fix output of __do_page_fault
Since commit 4bcc595ccd80 ("printk: reinstate KERN_CONT for printing
continuation lines") the output from __do_page_fault on MIPS has been
pretty unreadable due to the lack of KERN_CONT markers. Use pr_cont
to provide the appropriate markers & restore the expected output.

Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14544/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-11-25 12:08:10 +01:00
Paul Burton
1031398035 MIPS: Mask out limit field when calculating wired entry count
Since MIPSr6 the Wired register is split into 2 fields, with the upper
16 bits of the register indicating a limit on the value that the wired
entry count in the bottom 16 bits of the register can take. This means
that simply reading the wired register doesn't get us a valid TLB entry
index any longer, and we instead need to retrieve only the lower 16 bits
of the register. Introduce a new num_wired_entries() function which does
this on MIPSr6 or higher and simply returns the value of the wired
register on older architecture revisions, and make use of it when
reading the number of wired entries.

Since commit e710d6668309 ("MIPS: tlb-r4k: If there are wired entries,
don't use TLBINVF") we have been using a non-zero number of wired
entries to determine whether we should avoid use of the tlbinvf
instruction (which would invalidate wired entries) and instead loop over
TLB entries in local_flush_tlb_all(). This loop begins with the number
of wired entries, or before this patch some large bogus TLB index on
MIPSr6 systems. Thus since the aforementioned commit some MIPSr6 systems
with FTLBs have been prone to leaving stale address translations in the
FTLB & crashing in various weird & wonderful ways when we later observe
the wrong memory.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14557/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-11-24 16:44:16 +01:00
Linus Torvalds
63ae602cea Merge branch 'gup_flag-cleanups'
Merge the gup_flags cleanups from Lorenzo Stoakes:
 "This patch series adjusts functions in the get_user_pages* family such
  that desired FOLL_* flags are passed as an argument rather than
  implied by flags.

  The purpose of this change is to make the use of FOLL_FORCE explicit
  so it is easier to grep for and clearer to callers that this flag is
  being used.  The use of FOLL_FORCE is an issue as it overrides missing
  VM_READ/VM_WRITE flags for the VMA whose pages we are reading
  from/writing to, which can result in surprising behaviour.

  The patch series came out of the discussion around commit 38e088546522
  ("mm: check VMA flags to avoid invalid PROT_NONE NUMA balancing"),
  which addressed a BUG_ON() being triggered when a page was faulted in
  with PROT_NONE set but having been overridden by FOLL_FORCE.
  do_numa_page() was run on the assumption the page _must_ be one marked
  for NUMA node migration as an actual PROT_NONE page would have been
  dealt with prior to this code path, however FOLL_FORCE introduced a
  situation where this assumption did not hold.

  See

      https://marc.info/?l=linux-mm&m=147585445805166

  for the patch proposal"

Additionally, there's a fix for an ancient bug related to FOLL_FORCE and
FOLL_WRITE by me.

[ This branch was rebased recently to add a few more acked-by's and
  reviewed-by's ]

* gup_flag-cleanups:
  mm: replace access_process_vm() write parameter with gup_flags
  mm: replace access_remote_vm() write parameter with gup_flags
  mm: replace __access_remote_vm() write parameter with gup_flags
  mm: replace get_user_pages_remote() write/force parameters with gup_flags
  mm: replace get_user_pages() write/force parameters with gup_flags
  mm: replace get_vaddr_frames() write/force parameters with gup_flags
  mm: replace get_user_pages_locked() write/force parameters with gup_flags
  mm: replace get_user_pages_unlocked() write/force parameters with gup_flags
  mm: remove write/force parameters from __get_user_pages_unlocked()
  mm: remove write/force parameters from __get_user_pages_locked()
  mm: remove gup_flags FOLL_WRITE games from __get_user_pages()
2016-10-19 08:39:47 -07:00
Lorenzo Stoakes
c164154f66 mm: replace get_user_pages_unlocked() write/force parameters with gup_flags
This removes the 'write' and 'force' use from get_user_pages_unlocked()
and replaces them with 'gup_flags' to make the use of FOLL_FORCE
explicit in callers as use of this flag can result in surprising
behaviour (and hence bugs) within the mm subsystem.

Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-18 14:13:37 -07:00
Paul Burton
20d330645c MIPS: Support per-device DMA coherence
On some MIPS systems, a subset of devices may have DMA coherent with CPU
caches. For example in systems including a MIPS I/O Coherence Unit
(IOCU), some devices may be connected to that IOCU whilst others are
not.

Prior to this patch, we have a plat_device_is_coherent() function but no
implementation which does anything besides return a global true or
false, optionally chosen at runtime. For devices such as those described
above this is insufficient.

Fix this by tracking DMA coherence on a per-device basis with a
dma_coherent field in struct dev_archdata. Setting this from
arch_setup_dma_ops() takes care of devices which set the dma-coherent
property via device tree, and any PCI devices beneath a bridge described
in DT, automatically.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14349/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-10-06 18:02:01 +02:00
Paul Burton
cfa93fb9c2 MIPS: dma-default: Don't check hw_coherentio if device is non-coherent
There are no cases where plat_device_is_coherent() will return zero
whilst hw_coherentio is non-zero, and acting any differently in such a
case doesn't make much sense - if a device is non-coherent with the CPU
caches then access to memory "coherent" with DMA must be uncached. Clean
up the nonsensical case.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14348/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-10-06 18:01:45 +02:00
Paul Burton
f23020230e MIPS: Sanitise coherentio semantics
The coherentio variable has previously been used as a boolean value,
indicating whether the user specified that coherent I/O should be
enabled or disabled. It failed to take into account the case where the
user does not specify any preference, in which case it makes sense that
we should default to coherent I/O if the hardware supports it
(hw_coherentio is non-zero).

Introduce an enum to clarify the 3 different values of coherentio & use
it throughout the code, modifying plat_device_is_coherent() &
r4k_cache_init() to take into account the default case.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Paul Burton <paul.burton@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/14347/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-10-06 18:01:28 +02:00
Paul Gortmaker
d9ba577806 MIPS: mm: Audit and remove any unnecessary uses of module.h
Historically a lot of these existed because we did not have
a distinction between what was modular code and what was providing
support to modules via EXPORT_SYMBOL and friends.  That changed
when we forked out support for the latter into the export.h file.

This means we should be able to reduce the usage of module.h
in code that is obj-y Makefile or bool Kconfig.  The advantage
in doing so is that module.h itself sources about 15 other headers;
adding significantly to what we feed cpp, and it can obscure what
headers we are effectively using.

Since module.h was the source for init.h (for __init) and for
export.h (for EXPORT_SYMBOL) we consider each obj-y/bool instance
for the presence of either and replace as needed.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14033/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-10-05 01:31:20 +02:00
Matt Redfearn
e710d66683 MIPS: tlb-r4k: If there are wired entries, don't use TLBINVF
When adding a wired entry to the TLB via add_wired_entry, the tlb is
flushed with local_flush_tlb_all, which on CPUs with TLBINV results in
the new wired entry being flushed again.

Behavior of the TLBINV instruction applies to all applicable TLB entries
and is unaffected by the setting of the Wired register. Therefore if
the TLB has any wired entries, fall back to iterating over the entries
rather than blasting them all using TLBINVF.

Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Ohad Ben-Cohen <ohad@wizery.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: lisa.parratt@imgtec.com
Cc: Hugh Dickins <hughd@google.com>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mips@linux-mips.org
Cc: linux-remoteproc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14283/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-10-05 01:31:20 +02:00
James Hogan
b2ff71718e MIPS: c-r4k: Fix flush_icache_range() for EVA
flush_icache_range() flushes icache lines in a protected fashion for
kernel addresses, however this isn't correct with EVA where protected
cache ops only operate on user addresses, making flush_icache_range()
ineffective.

Split the implementations of __flush_icache_user_range() from
flush_icache_range(), changing the normal flush_icache_range() to use
unprotected normal cache ops.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14156/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-10-05 01:31:20 +02:00
James Hogan
8e3a9f4c3a MIPS: cacheflush: Use __flush_icache_user_range()
The cacheflush(2) system call uses flush_icache_range() to flush a range
of usermode addresses from the icache, so change it to utilise the new
__flush_icache_user_range() API to allow the more generic
flush_icache_range() to be changed to work on kernel addresses only.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14153/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-10-04 16:13:57 +02:00
James Hogan
01882b4d5e MIPS: c-r4k: Split user/kernel flush_icache_range()
flush_icache_range() is used for both user addresses (i.e.
cacheflush(2)), and kernel addresses (as the API documentation
describes).

This isn't really suitable however for Enhanced Virtual Addressing (EVA)
where cache operations on usermode addresses must use a different
instruction, and the protected cache ops assume user addresses, making
flush_icache_range() ineffective on kernel addresses.

Split out a new __flush_icache_user_range() and
__local_flush_icache_user_range() for users which actually want to flush
usermode addresses (note that flush_icache_user_range() already exists
on various architectures but with different arguments).

The implementation of flush_icache_range() will be changed in an
upcoming commit to use unprotected normal cache ops so as to always work
on the kernel mode address space.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14152/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-10-04 16:13:57 +02:00
James Hogan
d260d97e64 MIPS: c-r4k: Drop bc_wback_inv() from icache flush
The EVA conditional bc_wback_inv() at the end of flush_icache_range() to
flush the modified code all the way back to RAM was apparently there for
debug purposes and to accommodate the Malta EVA configuration which
makes use of a physical alias, and didn't use the CP0_EBase.WG (Write
Gate) bit to put the exception vector in the same physical alias where
the exception vector code is written and is being flushed.

Now that CP0_EBase.WG is used, lets drop this flush.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14151/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-10-04 16:13:57 +02:00
Paul Gortmaker
9f3b8081a4 MIPS: Migrate exception table users off module.h and onto extable.h
These files were only including module.h for exception table
related functions.  We've now separated that content out into its
own file "extable.h" so now move over to that and avoid all the
extra header content in module.h that we don't really need to compile
these files.

In the case of traps.c we can't dump the module.h include since it is
also used to provide "print_modules".

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/13934/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-10-04 16:13:57 +02:00
Paul Burton
058effe7fd MIPS: Fix detection of unsupported highmem with cache aliases
The paging_init() function contains code which detects that highmem is
in use but unsupported due to dcache aliasing. However this code was
ineffective because it was being run before the caches are probed,
meaning that cpu_has_dc_aliases would always evaluate to false (unless a
platform overrides it to a compile-time constant) and the detection of
the unsupported case is never triggered. The kernel would then go on to
attempt to use highmem & either hit coherency issues or trigger the
BUG_ON in flush_kernel_dcache_page().

Fix this by running paging_init() later than cpu_cache_init(), such that
the cpu_has_dc_aliases macro will evaluate correctly & the unsupported
highmem case will be detected successfully.

This then leads to a formerly hidden issue in that
mem_init_free_highmem() will attempt to free all highmem pages, even
though we're avoiding use of them & don't have valid page structs for
them. This leads to an invalid pointer dereference & a TLB exception.
Avoid this by skipping the loop in mem_init_free_highmem() if
cpu_has_dc_aliases evaluates true.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Rabin Vincent <rabinv@axis.com>
Cc: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: Jaedon Shin <jaedon.shin@gmail.com>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Cc: Jonas Gorski <jogo@openwrt.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14184/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-09-29 18:59:49 +02:00
Paul Burton
801f823dc2 MIPS: c-r4k: Fix size calc when avoiding IPIs for small icache flushes
Commit f70ddc07b637 ("MIPS: c-r4k: Avoid small flush_icache_range SMP
calls") adds checks to force use of hit-type cache ops for small icache
flushes where they are globalised & index-type cache ops aren't, in
order to avoid the overhead of IPIs in those cases. However it
calculated the size of the region being flushed incorrectly, subtracting
the end address from the start address rather than the reverse. This
would have led to an overflow with size wrapping round to some large
value, and likely to the special case for avoiding IPIs not actually
being hit.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Fixes: f70ddc07b637 ("MIPS: c-r4k: Avoid small flush_icache_range SMP calls")
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14211/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-09-13 17:37:20 +02:00
James Hogan
ac7e385f2b MIPS: MAAR: Fix address alignment
The alignment of MIPS MAAR region addresses isn't quite right.

- It rounds an already 64 KiB aligned start address up to the next
  64 KiB boundary, e.g. 0x80000000 is rounded up to 0x80010000.

- It assumes the end address is already on a 64 KiB boundary and doesn't
  round it down. Should that not be the case it will hit the second
  BUG_ON() in write_maar_pair().

Both cases are addressed by rounding up and down to 64 KiB boundaries in
the more traditional way of adding 0xffff (for rounding up) and masking
off the low 16 bits.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13858/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-09-13 14:13:26 +02:00
Linus Torvalds
4305f42401 Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
Pull MIPS updates from Ralf Baechle:
 "This is the main pull request for MIPS for 4.8.  Also includes is a
  minor SSB cleanup as SSB code traditionally is merged through the MIPS
  tree:

  ATH25:
    - MIPS: Add default configuration for ath25

  Boot:
    - For zboot, copy appended dtb to the end of the kernel
    - store the appended dtb address in a variable

  BPF:
    - Fix off by one error in offset allocation

  Cobalt code:
    - Fix typos

  Core code:
    - debugfs_create_file returns NULL on error, so don't use IS_ERR for
      testing for errors.
    - Fix double locking issue in RM7000 S-cache code.  This would only
      affect RM7000 ARC systems on reboot.
    - Fix page table corruption on THP permission changes.
    - Use compat_sys_keyctl for 32 bit userspace on 64 bit kernels.
      David says, there are no compatibility issues raised by this fix.
    - Move some signal code around.
    - Rewrite r4k count/compare clockevent device registration such that
      min_delta_ticks/max_delta_ticks files are guaranteed to be
      initialized.
    - Only register r4k count/compare as clockevent device if we can
      assume the clock to be constant.
    - Fix MSA asm warnings in control reg accessors
    - uasm and tlbex fixes and tweaking.
    - Print segment physical address when EU=1.
    - Define AT_VECTOR_SIZE_ARCH for ARCH_DLINFO.
    - CP: Allow booting by VP other than VP 0
    - Cache handling fixes and optimizations for r4k class caches
    - Add hotplug support for R6 processors
    - Cleanup hotplug bits in kconfig
    - traps: return correct si code for accessing nonmapped addresses
    - Remove cpu_has_safe_index_cacheops

  Lantiq:
    - Register IRQ handler for virtual IRQ number
    - Fix EIU interrupt loading code
    - Use the real EXIN count
    - Fix build error.

  Loongson 3:
    - Increase HPET_MIN_PROG_DELTA and decrease HPET_MIN_CYCLES

  Octeon:
    - Delete built-in DTB pruning code for D-Link DSR-1000N.
    - Clean up GPIO definitions in dlink_dsr-1000n.dts.
    - Add more LEDs to the DSR-100n DTS
    - Fix off by one in octeon_irq_gpio_map()
    - Typo fixes
    - Enable SATA by default in cavium_octeon_defconfig
    - Support readq/writeq()
    - Remove forced mappings of USB interrupts.
    - Ensure DMA descriptors are always in the low 4GB
    - Improve USB reset code for OCTEON II.

  Pistachio:
    - Add maintainers entry for pistachio SoC Support
    - Remove plat_setup_iocoherency

  Ralink:
    - Fix pwm UART in spis group pinmux.

  SSB:
    - Change bare unsigned to unsigned int to suit coding style

  Tools:
    - Fix reloc tool compiler warnings.

  Other:
    - Delete use of ARCH_WANT_OPTIONAL_GPIOLIB"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (61 commits)
  MIPS: mm: Fix definition of R6 cache instruction
  MIPS: tools: Fix relocs tool compiler warnings
  MIPS: Cobalt: Fix typo
  MIPS: Octeon: Fix typo
  MIPS: Lantiq: Fix build failure
  MIPS: Use CPHYSADDR to implement mips32 __pa
  MIPS: Octeon: Dlink_dsr-1000n.dts: add more leds.
  MIPS: Octeon: Clean up GPIO definitions in dlink_dsr-1000n.dts.
  MIPS: Octeon: Delete built-in DTB pruning code for D-Link DSR-1000N.
  MIPS: store the appended dtb address in a variable
  MIPS: ZBOOT: copy appended dtb to the end of the kernel
  MIPS: ralink: fix spis group pinmux
  MIPS: Factor o32 specific code into signal_o32.c
  MIPS: non-exec stack & heap when non-exec PT_GNU_STACK is present
  MIPS: Use per-mm page to execute branch delay slot instructions
  MIPS: Modify error handling
  MIPS: c-r4k: Use SMP calls for CM indexed cache ops
  MIPS: c-r4k: Avoid small flush_icache_range SMP calls
  MIPS: c-r4k: Local flush_icache_range cache op override
  MIPS: c-r4k: Split r4k_flush_kernel_vmap_range()
  ...
2016-08-06 09:13:11 -04:00
Krzysztof Kozlowski
00085f1efa dma-mapping: use unsigned long for dma_attrs
The dma-mapping core and the implementations do not change the DMA
attributes passed by pointer.  Thus the pointer can point to const data.
However the attributes do not have to be a bitfield.  Instead unsigned
long will do fine:

1. This is just simpler.  Both in terms of reading the code and setting
   attributes.  Instead of initializing local attributes on the stack
   and passing pointer to it to dma_set_attr(), just set the bits.

2. It brings safeness and checking for const correctness because the
   attributes are passed by value.

Semantic patches for this change (at least most of them):

    virtual patch
    virtual context

    @r@
    identifier f, attrs;

    @@
    f(...,
    - struct dma_attrs *attrs
    + unsigned long attrs
    , ...)
    {
    ...
    }

    @@
    identifier r.f;
    @@
    f(...,
    - NULL
    + 0
     )

and

    // Options: --all-includes
    virtual patch
    virtual context

    @r@
    identifier f, attrs;
    type t;

    @@
    t f(..., struct dma_attrs *attrs);

    @@
    identifier r.f;
    @@
    f(...,
    - NULL
    + 0
     )

Link: http://lkml.kernel.org/r/1468399300-5399-2-git-send-email-k.kozlowski@samsung.com
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Hans-Christian Noren Egtvedt <egtvedt@samfundet.no>
Acked-by: Mark Salter <msalter@redhat.com> [c6x]
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> [cris]
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> [drm]
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Acked-by: Joerg Roedel <jroedel@suse.de> [iommu]
Acked-by: Fabien Dessenne <fabien.dessenne@st.com> [bdisp]
Reviewed-by: Marek Szyprowski <m.szyprowski@samsung.com> [vb2-core]
Acked-by: David Vrabel <david.vrabel@citrix.com> [xen]
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> [xen swiotlb]
Acked-by: Joerg Roedel <jroedel@suse.de> [iommu]
Acked-by: Richard Kuo <rkuo@codeaurora.org> [hexagon]
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> [m68k]
Acked-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> [s390]
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Acked-by: Hans-Christian Noren Egtvedt <egtvedt@samfundet.no> [avr32]
Acked-by: Vineet Gupta <vgupta@synopsys.com> [arc]
Acked-by: Robin Murphy <robin.murphy@arm.com> [arm64 and dma-iommu]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-04 08:50:07 -04:00
Masahiro Yamada
97f2645f35 tree-wide: replace config_enabled() with IS_ENABLED()
The use of config_enabled() against config options is ambiguous.  In
practical terms, config_enabled() is equivalent to IS_BUILTIN(), but the
author might have used it for the meaning of IS_ENABLED().  Using
IS_ENABLED(), IS_BUILTIN(), IS_MODULE() etc.  makes the intention
clearer.

This commit replaces config_enabled() with IS_ENABLED() where possible.
This commit is only touching bool config options.

I noticed two cases where config_enabled() is used against a tristate
option:

 - config_enabled(CONFIG_HWMON)
  [ drivers/net/wireless/ath/ath10k/thermal.c ]

 - config_enabled(CONFIG_BACKLIGHT_CLASS_DEVICE)
  [ drivers/gpu/drm/gma500/opregion.c ]

I did not touch them because they should be converted to IS_BUILTIN()
in order to keep the logic, but I was not sure it was the authors'
intention.

Link: http://lkml.kernel.org/r/1465215656-20569-1-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Stas Sergeev <stsp@list.ru>
Cc: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Joshua Kinard <kumba@gentoo.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: "Dmitry V. Levin" <ldv@altlinux.org>
Cc: yu-cheng yu <yu-cheng.yu@intel.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Will Drewry <wad@chromium.org>
Cc: Nikolay Martynov <mar.kolya@gmail.com>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: Rafal Milecki <zajec5@gmail.com>
Cc: James Cowgill <James.Cowgill@imgtec.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Alex Smith <alex.smith@imgtec.com>
Cc: Adam Buchbinder <adam.buchbinder@gmail.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Mikko Rapeli <mikko.rapeli@iki.fi>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Brian Norris <computersforpeace@gmail.com>
Cc: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Cc: "Luis R. Rodriguez" <mcgrof@do-not-panic.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Roland McGrath <roland@hack.frob.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Kalle Valo <kvalo@qca.qualcomm.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Tony Wu <tung7970@gmail.com>
Cc: Huaitong Han <huaitong.han@intel.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrea Gelmini <andrea.gelmini@gelma.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Rabin Vincent <rabin@rab.in>
Cc: "Maciej W. Rozycki" <macro@imgtec.com>
Cc: David Daney <david.daney@cavium.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-04 08:50:07 -04:00
Ralf Baechle
4a89cf8101 Merge branch '4.7-fixes' into mips-for-linux-next 2016-08-03 12:55:49 +02:00
Matt Redfearn
4f53989b06 MIPS: mm: Fix definition of R6 cache instruction
Commit a168b8f1cde6 ("MIPS: mm: Add MIPS R6 instruction encodings") added
an incorrect definition of the redefined MIPSr6 cache instruction.

Executing any kernel code including this instuction results in a
reserved instruction exception and kernel panic.

Fix the instruction definition.

Fixes: a168b8f1cde6588ff7a67699fa11e01bc77a5ddd
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: <stable@vger.kernel.org> # 4.x-
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/13663/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-08-03 09:01:48 +02:00
Linus Torvalds
d52bd54db8 Merge branch 'akpm' (patches from Andrew)
Merge yet more updates from Andrew Morton:

 - the rest of ocfs2

 - various hotfixes, mainly MM

 - quite a bit of misc stuff - drivers, fork, exec, signals, etc.

 - printk updates

 - firmware

 - checkpatch

 - nilfs2

 - more kexec stuff than usual

 - rapidio updates

 - w1 things

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (111 commits)
  ipc: delete "nr_ipc_ns"
  kcov: allow more fine-grained coverage instrumentation
  init/Kconfig: add clarification for out-of-tree modules
  config: add android config fragments
  init/Kconfig: ban CONFIG_LOCALVERSION_AUTO with allmodconfig
  relay: add global mode support for buffer-only channels
  init: allow blacklisting of module_init functions
  w1:omap_hdq: fix regression
  w1: add helper macro module_w1_family
  w1: remove need for ida and use PLATFORM_DEVID_AUTO
  rapidio/switches: add driver for IDT gen3 switches
  powerpc/fsl_rio: apply changes for RIO spec rev 3
  rapidio: modify for rev.3 specification changes
  rapidio: change inbound window size type to u64
  rapidio/idt_gen2: fix locking warning
  rapidio: fix error handling in mbox request/release functions
  rapidio/tsi721_dma: advance queue processing from transfer submit call
  rapidio/tsi721: add messaging mbox selector parameter
  rapidio/tsi721: add PCIe MRRS override parameter
  rapidio/tsi721_dma: add channel mask and queue size parameters
  ...
2016-08-02 21:08:07 -04:00
Fabian Frederick
bd721ea73e treewide: replace obsolete _refok by __ref
There was only one use of __initdata_refok and __exit_refok

__init_refok was used 46 times against 82 for __ref.

Those definitions are obsolete since commit 312b1485fb50 ("Introduce new
section reference annotations tags: __ref, __refdata, __refconst")

This patch removes the following compatibility definitions and replaces
them treewide.

/* compatibility defines */
#define __init_refok     __ref
#define __initdata_refok __refdata
#define __exit_refok     __ref

I can also provide separate patches if necessary.
(One patch per tree and check in 1 month or 2 to remove old definitions)

[akpm@linux-foundation.org: coding-style fixes]
Link: http://lkml.kernel.org/r/1466796271-3043-1-git-send-email-fabf@skynet.be
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-02 17:31:41 -04:00
Linus Torvalds
221bb8a46e - ARM: GICv3 ITS emulation and various fixes. Removal of the old
VGIC implementation.
 
 - s390: support for trapping software breakpoints, nested virtualization
 (vSIE), the STHYI opcode, initial extensions for CPU model support.
 
 - MIPS: support for MIPS64 hosts (32-bit guests only) and lots of cleanups,
 preliminary to this and the upcoming support for hardware virtualization
 extensions.
 
 - x86: support for execute-only mappings in nested EPT; reduced vmexit
 latency for TSC deadline timer (by about 30%) on Intel hosts; support for
 more than 255 vCPUs.
 
 - PPC: bugfixes.
 
 The ugly bit is the conflicts.  A couple of them are simple conflicts due
 to 4.7 fixes, but most of them are with other trees. There was definitely
 too much reliance on Acked-by here.  Some conflicts are for KVM patches
 where _I_ gave my Acked-by, but the worst are for this pull request's
 patches that touch files outside arch/*/kvm.  KVM submaintainers should
 probably learn to synchronize better with arch maintainers, with the
 latter providing topic branches whenever possible instead of Acked-by.
 This is what we do with arch/x86.  And I should learn to refuse pull
 requests when linux-next sends scary signals, even if that means that
 submaintainers have to rebase their branches.
 
 Anyhow, here's the list:
 
 - arch/x86/kvm/vmx.c: handle_pcommit and EXIT_REASON_PCOMMIT was removed
 by the nvdimm tree.  This tree adds handle_preemption_timer and
 EXIT_REASON_PREEMPTION_TIMER at the same place.  In general all mentions
 of pcommit have to go.
 
 There is also a conflict between a stable fix and this patch, where the
 stable fix removed the vmx_create_pml_buffer function and its call.
 
 - virt/kvm/kvm_main.c: kvm_cpu_notifier was removed by the hotplug tree.
 This tree adds kvm_io_bus_get_dev at the same place.
 
 - virt/kvm/arm/vgic.c: a few final bugfixes went into 4.7 before the
 file was completely removed for 4.8.
 
 - include/linux/irqchip/arm-gic-v3.h: this one is entirely our fault;
 this is a change that should have gone in through the irqchip tree and
 pulled by kvm-arm.  I think I would have rejected this kvm-arm pull
 request.  The KVM version is the right one, except that it lacks
 GITS_BASER_PAGES_SHIFT.
 
 - arch/powerpc: what a mess.  For the idle_book3s.S conflict, the KVM
 tree is the right one; everything else is trivial.  In this case I am
 not quite sure what went wrong.  The commit that is causing the mess
 (fd7bacbca47a, "KVM: PPC: Book3S HV: Fix TB corruption in guest exit
 path on HMI interrupt", 2016-05-15) touches both arch/powerpc/kernel/
 and arch/powerpc/kvm/.  It's large, but at 396 insertions/5 deletions
 I guessed that it wasn't really possible to split it and that the 5
 deletions wouldn't conflict.  That wasn't the case.
 
 - arch/s390: also messy.  First is hypfs_diag.c where the KVM tree
 moved some code and the s390 tree patched it.  You have to reapply the
 relevant part of commits 6c22c9863760, plus all of e030c1125eab, to
 arch/s390/kernel/diag.c.  Or pick the linux-next conflict
 resolution from http://marc.info/?l=kvm&m=146717549531603&w=2.
 Second, there is a conflict in gmap.c between a stable fix and 4.8.
 The KVM version here is the correct one.
 
 I have pushed my resolution at refs/heads/merge-20160802 (commit
 3d1f53419842) at git://git.kernel.org/pub/scm/virt/kvm/kvm.git.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:

 - ARM: GICv3 ITS emulation and various fixes.  Removal of the
   old VGIC implementation.

 - s390: support for trapping software breakpoints, nested
   virtualization (vSIE), the STHYI opcode, initial extensions
   for CPU model support.

 - MIPS: support for MIPS64 hosts (32-bit guests only) and lots
   of cleanups, preliminary to this and the upcoming support for
   hardware virtualization extensions.

 - x86: support for execute-only mappings in nested EPT; reduced
   vmexit latency for TSC deadline timer (by about 30%) on Intel
   hosts; support for more than 255 vCPUs.

 - PPC: bugfixes.

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (302 commits)
  KVM: PPC: Introduce KVM_CAP_PPC_HTM
  MIPS: Select HAVE_KVM for MIPS64_R{2,6}
  MIPS: KVM: Reset CP0_PageMask during host TLB flush
  MIPS: KVM: Fix ptr->int cast via KVM_GUEST_KSEGX()
  MIPS: KVM: Sign extend MFC0/RDHWR results
  MIPS: KVM: Fix 64-bit big endian dynamic translation
  MIPS: KVM: Fail if ebase doesn't fit in CP0_EBase
  MIPS: KVM: Use 64-bit CP0_EBase when appropriate
  MIPS: KVM: Set CP0_Status.KX on MIPS64
  MIPS: KVM: Make entry code MIPS64 friendly
  MIPS: KVM: Use kmap instead of CKSEG0ADDR()
  MIPS: KVM: Use virt_to_phys() to get commpage PFN
  MIPS: Fix definition of KSEGX() for 64-bit
  KVM: VMX: Add VMCS to CPU's loaded VMCSs before VMPTRLD
  kvm: x86: nVMX: maintain internal copy of current VMCS
  KVM: PPC: Book3S HV: Save/restore TM state in H_CEDE
  KVM: PPC: Book3S HV: Pull out TM state save/restore into separate procedures
  KVM: arm64: vgic-its: Simplify MAPI error handling
  KVM: arm64: vgic-its: Make vgic_its_cmd_handle_mapi similar to other handlers
  KVM: arm64: vgic-its: Turn device_id validation into generic ID validation
  ...
2016-08-02 16:11:27 -04:00
Amitoj Kaur Chawla
33799a6d1a MIPS: Modify error handling
debugfs_create_file returns NULL on error so an IS_ERR test is
incorrect here and a NULL check is required.

The Coccinelle semantic patch used to make this change is as follows:
@@
expression e;
@@

  e = debugfs_create_file(...);
if(
-    IS_ERR(e)
+    !e
    )
    {
  <+...
  return
- PTR_ERR(e)
+ -ENOMEM
  ;
  ...+>
  }

Signed-off-by: Amitoj Kaur Chawla <amitoj1606@gmail.com>
Cc: julia.lawall@lip6.fr
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/13834/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-08-01 22:54:48 +02:00
James Hogan
11f769039e MIPS: c-r4k: Use SMP calls for CM indexed cache ops
The MIPS Coherence Manager (CM) can propagate address-based ("hit")
cache operations to other cores in the coherent system, alleviating
software of the need to use SMP calls, however indexed cache operations
are not propagated by hardware since doing so makes no sense for
separate caches.

Update r4k_op_needs_ipi() to report that only hit cache operations are
globalized by the CM, requiring indexed cache operations to be
globalized by software via an SMP call.

r4k_on_each_cpu() previously had a special case for CONFIG_MIPS_MT_SMP,
intended to avoid the SMP calls when the only other CPUs in the system
were other VPEs in the same core, and hence sharing the same caches.
This was changed by commit cccf34e9411c ("MIPS: c-r4k: Fix cache
flushing for MT cores") to apparently handle multi-core multi-VPE
systems, but it focussed mainly on hit cache ops, so the SMP calls were
still disabled entirely for CM systems.

This doesn't normally cause problems, but tests can be written to hit
these corner cases by using multiple threads, or changing task
affinities to force the process to migrate cores. For example the
failure of mprotect RW->RX to globally sync icaches (via
flush_cache_range) can be detected by modifying and mprotecting a code
page on one core, and migrating to a different core to execute from it.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13807/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-07-29 10:19:30 +02:00
James Hogan
f70ddc07b6 MIPS: c-r4k: Avoid small flush_icache_range SMP calls
Avoid SMP calls for flushing small icache ranges. On non-CM platforms,
and CM platforms too after we make r4k_on_each_cpu() take the cache op
type into account, it will be called on multiple CPUs due to the
possibility that local_r4k_flush_icache_range_ipi() could do
non-globalized indexed cache ops. This rougly copies the range size
check out into r4k_flush_icache_range(), which can disallow indexed
cache ops and allow r4k_on_each_cpu() to skip the SMP call.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13805/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-07-29 10:19:30 +02:00
James Hogan
27b93d9c1d MIPS: c-r4k: Local flush_icache_range cache op override
Allow the permitted cache op types used by
local_r4k_flush_icache_range_ipi() to be overridden by the SMP caller.
This will allow SMP calls to be avoided under certain circumstances,
falling back to a single CPU performing globalized hit cache ops only.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13803/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-07-29 10:19:30 +02:00
James Hogan
a9341ae241 MIPS: c-r4k: Split r4k_flush_kernel_vmap_range()
Split the operation of r4k_flush_kernel_vmap_range() into separate
SMP callbacks for the indexed cache flush and hit cache flush cases,
since the logic to determine which to use can be determined by the
initiating CPU prior to doing any SMP calls.

This will help when we change r4k_on_each_cpu() to distinguish indexed
and hit cache ops in a later patch, preventing globalized hit cache ops
being performed redundantly on multiple CPUs.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13806/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-07-29 10:19:29 +02:00
James Hogan
640511ae92 MIPS: c-r4k: Exclude sibling CPUs in SMP calls
When performing SMP calls to foreign cores, exclude sibling CPUs from
the provided map, as we already handle the local core on the current
CPU. This prevents an SMP call from for example core 0, VPE 1 to VPE 0
on the same core.

In the process the cpu_foreign_map cpumask is turned into an array of
cpumasks, so that each CPU has its own version of it which excludes
sibling CPUs. r4k_op_needs_ipi() is also updated to reflect that cache
management SMP calls are not needed when all CPUs are siblings (i.e.
there are no foreign CPUs according to the new cpu_foreign_map[]
semantics which exclude siblings).

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com>
Cc: Felix Fietkau <nbd@nbd.name>
Cc: Jayachandran C. <jchandra@broadcom.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13801/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-07-29 10:19:29 +02:00
James Hogan
6d758bfc7b MIPS: c-r4k: Fix valid ASID optimisation
Several cache operations are optimised to return early from the SMP call
handler if the memory map in question has no valid ASID on the current
CPU, or any online CPU in the case of MIPS_MT_SMP. The idea is that if a
memory map has never been used on a CPU it shouldn't have cache lines in
need of flushing.

However this doesn't cover all cases when ASIDs for other CPUs need to
be checked:
- Offline VPEs may have recently been online and brought lines into the
  (shared) cache, so they should also be checked, rather than only
  online CPUs.
- SMP systems with a Coherence Manager (CM), but with MT disabled still
  have globalized hit cache ops, but don't use SMP calls, so all present
  CPUs should be taken into account.
- R6 systems have a different multithreading implementation, so
  MIPS_MT_SMP won't be set, but as above may still have a CM which
  globalizes hit cache ops.

Additionally for non-globalized cache operations where an SMP call to a
single VPE in each foreign core is used, it is not necessary to check
every CPU in the system, only sibling CPUs sharing the same first level
cache.

Fix this by making has_valid_asid() take a cache op type argument like
r4k_on_each_cpu(), so it can determine whether r4k_on_each_cpu() will
have done SMP calls to other cores. It can then determine which set of
CPUs to check the ASIDs of based on that, excluding foreign CPUs if an
SMP call will have been performed.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13804/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-07-29 10:19:29 +02:00