When we reach the loop, len is at least 1, we only stay in the loop when
len is at least MAX_BYTE_COUNT + 1, MAX_BYTE_COUNT is subtracted in each
iteration. So when we leave the loop, or didn't take it, len is at least 1.
Testing whether len is non-zero appears redundant.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/xfs-vipt:
xfs: fix xfs to work with Virtually Indexed architectures
sh: add mm API for DMA to vmalloc/vmap areas
arm: add mm API for DMA to vmalloc/vmap areas
parisc: add mm API for DMA to vmalloc/vmap areas
mm: add coherence API for DMA to vmalloc/vmap areas
On VIVT ARM, when we have multiple shared mappings of the same file
in the same MM, we need to ensure that we have coherency across all
copies. We do this via make_coherent() by making the pages
uncacheable.
This used to work fine, until we allowed highmem with highpte - we
now have a page table which is mapped as required, and is not available
for modification via update_mmu_cache().
Ralf Beache suggested getting rid of the PTE value passed to
update_mmu_cache():
On MIPS update_mmu_cache() calls __update_tlb() which walks pagetables
to construct a pointer to the pte again. Passing a pte_t * is much
more elegant. Maybe we might even replace the pte argument with the
pte_t?
Ben Herrenschmidt would also like the pte pointer for PowerPC:
Passing the ptep in there is exactly what I want. I want that
-instead- of the PTE value, because I have issue on some ppc cases,
for I$/D$ coherency, where set_pte_at() may decide to mask out the
_PAGE_EXEC.
So, pass in the mapped page table pointer into update_mmu_cache(), and
remove the PTE value, updating all implementations and call sites to
suit.
Includes a fix from Stephen Rothwell:
sparc: fix fallout from update_mmu_cache API change
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch fix the below build error for arm1026ej-s processor (IntegratorCP/arm1026ej-s board).
CC init/main.o
In file included from include/linux/highmem.h:8,
from include/linux/pagemap.h:10,
from include/linux/mempolicy.h:62,
from init/main.c:52:
arch/arm/include/asm/cacheflush.h:134:2: error: #error Unknown cache maintainence model
make[1]: *** [init/main.o] Erreur 1
make: *** [init] Erreur 2
Signed-off-by: Abdoulaye Walsimou Gaye <walsimou@walsimou.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Makes it consistent with VMALLOC_START
Tested-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Andreas Fenkart <andreas.fenkart@streamunlimited.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Adds DMA area to 'virtual memory map' startup message
Tested-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Andreas Fenkart <andreas.fenkart@streamunlimited.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
If we're only reading the VFP context via the ptrace call, there's
no need to invalidate the hardware context - we only need to do that
on PTRACE_SETVFPREGS. This allows more efficient monitoring of a
traced task.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The current ASID allocation algorithm doesn't ensure the notification
of the other CPUs when the ASID rolls over. This may lead to two
processes using the same ASID (but different generation) or multiple
threads of the same process using different ASIDs.
This patch adds the broadcasting of the ASID rollover event to the
other CPUs. To avoid a race on multiple CPUs modifying "cpu_last_asid"
during the handling of the broadcast, the ASID numbering now starts at
"smp_processor_id() + 1". At rollover, the cpu_last_asid will be set
to NR_CPUS.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
On ARMv7, the use of the cp15 operations for barriers is deprecated
in favour of the isb, dsb, and dmb instructions. Change the locking
functions to use the appropriate type of dsb for the architecture
being built for.
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
In preparation for perf-events support, ARM needs to support atomic64_t
operations. v6k and above support the ldrexd and strexd instructions to
do just that.
This patch adds atomic64 support to the ARM architecture. v6k and above
make use of new instructions whilst older cores fall back on the generic
solution using spinlocks. If and when v7-M cores are supported by Linux,
they will need to fall back on the spinlock implementation too.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Kernel debuggers want to be informed of die() events, so that they
can take some action to allow the problem to be inspected. Provide
the hook in a similar manner to x86.
Note that we currently don't implement the individual trap hooks.
Acked-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The ARM setup code includes its own parser for early params, there's
also one in the generic init code.
This patch removes __early_init (and related code) from
arch/arm/kernel/setup.c, and changes users to the generic early_init
macro instead.
The generic macro takes a char * argument, rather than char **, so we
need to update the parser functions a little.
Signed-off-by: Jeremy Kerr <jeremy.kerr@canonical.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
All RTC drivers have been converted to rtclib, so the old code
providing the set_rtc function pointer, save_time_delta() and
restore_time_delta() functions is obsolete. Remove it.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This allows the procfs vmallocinfo file to show who created the ioremap
regions. Note: __builtin_return_address(0) doesn't do what's expected
if its used in an inline function, so we leave __arm_ioremap callers
in such places alone.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
These are now unused, and so can be removed.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-By: Santosh Shilimkar <santosh.shilimkar@ti.com>
The DMA API has the notion of buffer ownership; make it explicit in the
ARM implementation of this API. This gives us a set of hooks to allow
us to deal with CPU cache issues arising from non-cache coherent DMA.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-By: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-By: Jamie Iles <jamie@jamieiles.com>
Most machine classes want some way to register a block of clk_lookup
structures, and most do it by implementing a clks_register() type
function which walks an array, or by open-coding a loop.
Consolidate all this into clkdev_add_table().
Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Kevin Hilman <khilman@deeprootsystems.com>
Acked-by: Eric Miao <eric.y.miao@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The perf events subsystem allows counting of both hardware and
software events. This patch implements the bare minimum for software
performance events.
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jamie Iles <jamie.iles@picochip.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
To add support for perf events and to allow the hardware counters to be
shared with oprofile, we need a way to reserve access to the pmu
(performance monitor unit). Platforms with PMU interrupts should
register the interrupts in arch/arm/kernel/pmu.c
Signed-off-by: Jamie Iles <jamie.iles@picochip.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM cannot prevent cache movein, so this patch implements both the
flush and invalidate pieces of the API.
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
The comments in cacheflush.h should follow what's in
struct cpu_cache_fns. The comments for V6 and V7 are
unnecessary.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The file arch/arm/include/asm/cpu.h needs to include 'linux/cpu.h' to
meet its dependency. Otherwise when using "struct cpuinfo_arm" and
including just 'asm/cpu.h' throws below error -
arch/arm/include/asm/cpu.h:16: error: field 'cpu' has incomplete type
To fix this otherway, one can also include both linux/cpu.h and
asm/cpu.h but it shoudn't be that way. So this patch fixes this by
including the linux/cpu.h in asm/cpu.h, so that including alone
asm/cpu.h is enough.
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
A lot of ARM-defconfigs (those without CONFIG_ISA_DMA_API set) fail to
build [1][2][3] due to the changes of the patch
[PATCH] PCI: Clean up build for CONFIG_PCI_QUIRKS unset
by Rafael J. Wysocki (Sat, 2 Jan 2010 22:57:24 +0100) [4]
as the referenced variable 'isa_dma_bridge_buggy' in asm/dma.h is
enclosed by the CONFIG_ISA_DMA_API conditional all configs without this
setting fail to build.
I'm not sure wether moving the condition is the right way to solve the
issue, but atleast it fixes the issue :)
References:
[1] http://kisskb.ellerman.id.au/kisskb/buildresult/1983354/
[2] http://kisskb.ellerman.id.au/kisskb/buildresult/1983333/
[3] http://kisskb.ellerman.id.au/kisskb/buildresult/1983337/
[4] http://lkml.org/lkml/2010/1/2/102
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Make registers unsigned for kernel space. This is important for
example in the perf events where the PC is stored into a u64. We
don't want it sign extended so make the regs unsigned to prevent
casts throughout the kernel.
Signed-off-by: Jamie Iles <jamie.iles@picochip.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
26-bit ARM support was removed a long time ago, and this symbol has
been defined to be 'y' ever since. As it's never disabled anymore,
we can kill it without any side effects.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This avoids races in the VFP code where the dead thread may have
state on another CPU. By moving this code to exit_thread(), we
will be running as the thread, and therefore be running on the
current CPU.
This means that we can ensure that the only local state is accessed
in the thread notifiers.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm:
PCMCIA: fix pxa2xx_lubbock modular build error
[ARM] Update mach-types
[ARM] pxa: fix no reference of cpu_is_pxa25x() in devices.c
[ARM] pxa/cm-x300: add PWM backlight support
revert "[ARM] pxa/cm-x300: add PWM backlight support"
ARM: use flush_kernel_dcache_area() for dmabounce
ARM: add size argument to __cpuc_flush_dcache_page
ARM: 5848/1: kill flush_ioremap_region()
ARM: cache-l2x0: make better use of background cache handling
ARM: cache-l2x0: avoid taking spinlock for every iteration
[ARM] Kirkwood: Add LaCie Network Space v2 support
ARM: dove: fix the mm mmu flags of the pj4 procinfo
* 'for-33' of git://repo.or.cz/linux-kbuild: (29 commits)
net: fix for utsrelease.h moving to generated
gen_init_cpio: fixed fwrite warning
kbuild: fix make clean after mismerge
kbuild: generate modules.builtin
genksyms: properly consider EXPORT_UNUSED_SYMBOL{,_GPL}()
score: add asm/asm-offsets.h wrapper
unifdef: update to upstream revision 1.190
kbuild: specify absolute paths for cscope
kbuild: create include/generated in silentoldconfig
scripts/package: deb-pkg: use fakeroot if available
scripts/package: add KBUILD_PKG_ROOTCMD variable
scripts/package: tar-pkg: use tar --owner=root
Kbuild: clean up marker
net: add net_tstamp.h to headers_install
kbuild: move utsrelease.h to include/generated
kbuild: move autoconf.h to include/generated
drop explicit include of autoconf.h
kbuild: move compile.h to include/generated
kbuild: drop include/asm
kbuild: do not check for include/asm-$ARCH
...
Fixed non-conflicting clean merge of modpost.c as per comments from
Stephen Rothwell (modpost.c had grown an include of linux/autoconf.h
that needed to be changed to generated/autoconf.h)
Currently all architectures but microblaze unconditionally define
USE_ELF_CORE_DUMP. The microblaze omission seems like an error to me, so
let's kill this ifdef and make sure we are the same everywhere.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: <linux-arch@vger.kernel.org>
Cc: Michal Simek <michal.simek@petalogix.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Convert locks which cannot be sleeping locks in preempt-rt to
raw_spinlocks.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Name space cleanup for rwlock functions. No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: linux-arch@vger.kernel.org
Not strictly necessary for -rt as -rt does not have non sleeping
rwlocks, but it's odd to not have a consistent naming convention.
No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: linux-arch@vger.kernel.org
Name space cleanup. No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: linux-arch@vger.kernel.org
Further name space cleanup. No functional change
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: linux-arch@vger.kernel.org
The raw_spin* namespace was taken by lockdep for the architecture
specific implementations. raw_spin_* would be the ideal name space for
the spinlocks which are not converted to sleeping locks in preempt-rt.
Linus suggested to convert the raw_ to arch_ locks and cleanup the
name space instead of using an artifical name like core_spin,
atomic_spin or whatever
No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: linux-arch@vger.kernel.org
There is not enough users to warrant its existence, and it is actually
an obstacle to progress with the new DMA API which cannot cover this
case properly.
To keep backward compatibility, let's perform the necessary custom
cache maintenance locally in the only driver affected.
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Simplified arch/arm/Makefile by dropping the maketools target
It was undocumented and not needed
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Michal Marek <mmarek@suse.cz>
The simplest method was to add an extra asm-offsets.h
file in arch/$ARCH/include/asm that references the generated file.
We can now migrate the architectures one-by-one to reference
the generated file direct - and when done we can delete the
temporary arch/$ARCH/include/asm/asm-offsets.h file.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Michal Marek <mmarek@suse.cz>
Linus Torvalds