We want to be able to use the utf16 functions that are currently present
in the EFI variables code in platform-specific code as well. Move them to
the kernel core, and in the process rename them to accurately describe what
they do - they don't handle UTF16, only UCS2.
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Pull powerpc update from Benjamin Herrenschmidt:
"The main highlight is probably some base POWER8 support. There's more
to come such as transactional memory support but that will wait for
the next one.
Overall it's pretty quiet, or rather I've been pretty poor at picking
things up from patchwork and reviewing them this time around and Kumar
no better on the FSL side it seems..."
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (73 commits)
powerpc+of: Rename and fix OF reconfig notifier error inject module
powerpc: mpc5200: Add a3m071 board support
powerpc/512x: don't compile any platform DIU code if the DIU is not enabled
powerpc/mpc52xx: use module_platform_driver macro
powerpc+of: Export of_reconfig_notifier_[register,unregister]
powerpc/dma/raidengine: add raidengine device
powerpc/iommu/fsl: Add PAMU bypass enable register to ccsr_guts struct
powerpc/mpc85xx: Change spin table to cached memory
powerpc/fsl-pci: Add PCI controller ATMU PM support
powerpc/86xx: fsl_pcibios_fixup_bus requires CONFIG_PCI
drivers/virt: the Freescale hypervisor driver doesn't need to check MSR[GS]
powerpc/85xx: p1022ds: Use NULL instead of 0 for pointers
powerpc: Disable relocation on exceptions when kexecing
powerpc: Enable relocation on during exceptions at boot
powerpc: Move get_longbusy_msecs into hvcall.h and remove duplicate function
powerpc: Add wrappers to enable/disable relocation on exceptions
powerpc: Add set_mode hcall
powerpc: Setup relocation on exceptions for bare metal systems
powerpc: Move initial mfspr LPCR out of __init_LPCR
powerpc: Add relocation on exception vector handlers
...
Currently the writer does msleep() plus synchronize_sched() 3 times to
acquire/release the semaphore, and during this time the readers are
blocked completely. Even if the "write" section was not actually started
or if it was already finished.
With this patch down_write/up_write does synchronize_sched() twice and
down_read/up_read are still possible during this time, just they use the
slow path.
percpu_down_write() first forces the readers to use rw_semaphore and
increment the "slow" counter to take the lock for reading, then it
takes that rw_semaphore for writing and blocks the readers.
Also. With this patch the code relies on the documented behaviour of
synchronize_sched(), it doesn't try to pair synchronize_sched() with
barrier.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull x86 ACPI update from Peter Anvin:
"This is a patchset which didn't make the last merge window. It adds a
debugging capability to feed ACPI tables via the initramfs.
On a grander scope, it formalizes using the initramfs protocol for
feeding arbitrary blobs which need to be accessed early to the kernel:
they are fed first in the initramfs blob (lots of bootloaders can
concatenate this at boot time, others can use a single file) in an
uncompressed cpio archive using filenames starting with "kernel/".
The ACPI maintainers requested that this patchset be fed via the x86
tree rather than the ACPI tree as the footprint in the general x86
code is much bigger than in the ACPI code proper."
* 'x86-acpi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
X86 ACPI: Use #ifdef not #if for CONFIG_X86 check
ACPI: Fix build when disabled
ACPI: Document ACPI table overriding via initrd
ACPI: Create acpi_table_taint() function to avoid code duplication
ACPI: Implement physical address table override
ACPI: Store valid ACPI tables passed via early initrd in reserved memblock areas
x86, acpi: Introduce x86 arch specific arch_reserve_mem_area() for e820 handling
lib: Add early cpio decoder
This module used to inject errors in the pSeries specific dynamic
reconfiguration notifiers. Those are gone however, replaced by
generic notifiers for changes to the device-tree. So let's update
the module to deal with these instead and rename it along the way.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Akinobu Mita <akinobu.mita@gmail.com>
Here's the large driver core updates for 3.8-rc1.
The biggest thing here is the various __dev* marking removals. This is
going to be a pain for the merge with different subsystem trees, I know,
but all of the patches included here have been ACKed by their various
subsystem maintainers, as they wanted them to go through here.
If this is too much of a pain, I can pull all of them out of this tree
and just send you one with the other fixes/updates and then, after
3.8-rc1 is out, do the rest of the removals to ensure we catch them all,
it's up to you. The merges should all be trivial, and Stephen has been
doing them all in linux-next for a few weeks now quite easily.
Other than the __dev* marking removals, there's nothing major here, some
firmware loading updates and other minor things in the driver core.
All of these have (much to Stephen's annoyance), been in linux-next for
a while.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg Kroah-Hartman:
"Here's the large driver core updates for 3.8-rc1.
The biggest thing here is the various __dev* marking removals. This
is going to be a pain for the merge with different subsystem trees, I
know, but all of the patches included here have been ACKed by their
various subsystem maintainers, as they wanted them to go through here.
If this is too much of a pain, I can pull all of them out of this tree
and just send you one with the other fixes/updates and then, after
3.8-rc1 is out, do the rest of the removals to ensure we catch them
all, it's up to you. The merges should all be trivial, and Stephen
has been doing them all in linux-next for a few weeks now quite
easily.
Other than the __dev* marking removals, there's nothing major here,
some firmware loading updates and other minor things in the driver
core.
All of these have (much to Stephen's annoyance), been in linux-next
for a while.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"
Fixed up trivial conflicts in drivers/gpio/gpio-{em,stmpe}.c due to gpio
update.
* tag 'driver-core-3.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (93 commits)
modpost.c: Stop checking __dev* section mismatches
init.h: Remove __dev* sections from the kernel
acpi: remove use of __devinit
PCI: Remove __dev* markings
PCI: Always build setup-bus when PCI is enabled
PCI: Move pci_uevent into pci-driver.c
PCI: Remove CONFIG_HOTPLUG ifdefs
unicore32/PCI: Remove CONFIG_HOTPLUG ifdefs
sh/PCI: Remove CONFIG_HOTPLUG ifdefs
powerpc/PCI: Remove CONFIG_HOTPLUG ifdefs
mips/PCI: Remove CONFIG_HOTPLUG ifdefs
microblaze/PCI: Remove CONFIG_HOTPLUG ifdefs
dma: remove use of __devinit
dma: remove use of __devexit_p
firewire: remove use of __devinitdata
firewire: remove use of __devinit
leds: remove use of __devexit
leds: remove use of __devinit
leds: remove use of __devexit_p
mmc: remove use of __devexit
...
It is $(obj)/oid_registry.o that is dependent on $(obj)/oid_registry_data.c.
The object file cannot be built until $(obj)/oid_registry_data.c has been
generated.
A periodic and hard to reproduce parallel build failure is due to
this incorrect lib/Makefile dependency. The compile error is completely
disingenuous.
GEN lib/oid_registry_data.c
Compiling 49 OIDs
CC lib/oid_registry.o
gcc: error: lib/oid_registry.c: No such file or directory
gcc: fatal error: no input files
compilation terminated.
make[3]: *** [lib/oid_registry.o] Error 4
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: David Howells <dhowells@redhat.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
CONFIG_HOTPLUG is being removed so kobject_uevent needs to always be
part of the library.
Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull module signing support from Rusty Russell:
"module signing is the highlight, but it's an all-over David Howells frenzy..."
Hmm "Magrathea: Glacier signing key". Somebody has been reading too much HHGTTG.
* 'modules-next' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (37 commits)
X.509: Fix indefinite length element skip error handling
X.509: Convert some printk calls to pr_devel
asymmetric keys: fix printk format warning
MODSIGN: Fix 32-bit overflow in X.509 certificate validity date checking
MODSIGN: Make mrproper should remove generated files.
MODSIGN: Use utf8 strings in signer's name in autogenerated X.509 certs
MODSIGN: Use the same digest for the autogen key sig as for the module sig
MODSIGN: Sign modules during the build process
MODSIGN: Provide a script for generating a key ID from an X.509 cert
MODSIGN: Implement module signature checking
MODSIGN: Provide module signing public keys to the kernel
MODSIGN: Automatically generate module signing keys if missing
MODSIGN: Provide Kconfig options
MODSIGN: Provide gitignore and make clean rules for extra files
MODSIGN: Add FIPS policy
module: signature checking hook
X.509: Add a crypto key parser for binary (DER) X.509 certificates
MPILIB: Provide a function to read raw data into an MPI
X.509: Add an ASN.1 decoder
X.509: Add simple ASN.1 grammar compiler
...
After both prio_tree users have been converted to use red-black trees,
there is no need to keep around the prio tree library anymore.
Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch 1 implements support for interval trees, on top of the augmented
rbtree API. It also adds synthetic tests to compare the performance of
interval trees vs prio trees. Short answers is that interval trees are
slightly faster (~25%) on insert/erase, and much faster (~2.4 - 3x)
on search. It is debatable how realistic the synthetic test is, and I have
not made such measurements yet, but my impression is that interval trees
would still come out faster.
Patch 2 uses a preprocessor template to make the interval tree generic,
and uses it as a replacement for the vma prio_tree.
Patch 3 takes the other prio_tree user, kmemleak, and converts it to use
a basic rbtree. We don't actually need the augmented rbtree support here
because the intervals are always non-overlapping.
Patch 4 removes the now-unused prio tree library.
Patch 5 proposes an additional optimization to rb_erase_augmented, now
providing it as an inline function so that the augmented callbacks can be
inlined in. This provides an additional 5-10% performance improvement
for the interval tree insert/erase benchmark. There is a maintainance cost
as it exposes augmented rbtree users to some of the rbtree library internals;
however I think this cost shouldn't be too high as I expect the augmented
rbtree will always have much less users than the base rbtree.
I should probably add a quick summary of why I think it makes sense to
replace prio trees with augmented rbtree based interval trees now. One of
the drivers is that we need augmented rbtrees for Rik's vma gap finding
code, and once you have them, it just makes sense to use them for interval
trees as well, as this is the simpler and more well known algorithm. prio
trees, in comparison, seem *too* clever: they impose an additional 'heap'
constraint on the tree, which they use to guarantee a faster worst-case
complexity of O(k+log N) for stabbing queries in a well-balanced prio
tree, vs O(k*log N) for interval trees (where k=number of matches,
N=number of intervals). Now this sounds great, but in practice prio trees
don't realize this theorical benefit. First, the additional constraint
makes them harder to update, so that the kernel implementation has to
simplify things by balancing them like a radix tree, which is not always
ideal. Second, the fact that there are both index and heap properties
makes both tree manipulation and search more complex, which results in a
higher multiplicative time constant. As it turns out, the simple interval
tree algorithm ends up running faster than the more clever prio tree.
This patch:
Add two test modules:
- prio_tree_test measures the performance of lib/prio_tree.c, both for
insertion/removal and for stabbing searches
- interval_tree_test measures the performance of a library of equivalent
functionality, built using the augmented rbtree support.
In order to support the second test module, lib/interval_tree.c is
introduced. It is kept separate from the interval_tree_test main file
for two reasons: first we don't want to provide an unfair advantage
over prio_tree_test by having everything in a single compilation unit,
and second there is the possibility that the interval tree functionality
could get some non-test users in kernel over time.
Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This small module helps measure the performance of rbtree insert and
erase.
Additionally, we run a few correctness tests to check that the rbtrees
have all desired properties:
- contains the right number of nodes in the order desired,
- never two consecutive red nodes on any path,
- all paths to leaf nodes have the same number of black nodes,
- root node is black
[akpm@linux-foundation.org: fix printk warning: sparc64 cycles_t is unsigned long]
Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: David Woodhouse <David.Woodhouse@intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Daniel Santos <daniel.santos@pobox.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add an ASN.1 BER/DER/CER decoder. This uses the bytecode from the ASN.1
compiler in the previous patch to inform it as to what to expect to find in the
encoded byte stream. The output from the compiler also tells it what functions
to call on what tags, thus allowing the caller to retrieve information.
The decoder is called as follows:
int asn1_decoder(const struct asn1_decoder *decoder,
void *context,
const unsigned char *data,
size_t datalen);
The decoder argument points to the bytecode from the ASN.1 compiler. context
is the caller's context and is passed to the action functions. data and
datalen define the byte stream to be decoded.
Note that the decoder is currently limited to datalen being less than 64K.
This reduces the amount of stack space used by the decoder because ASN.1 is a
nested construct. Similarly, the decoder is limited to a maximum of 10 levels
of constructed data outside of a leaf node also in an effort to keep stack
usage down.
These restrictions can be raised if necessary.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Implement a simple static OID registry that allows the mapping of an encoded
OID to an enum value for ease of use.
The OID registry index enum appears in the:
linux/oid_registry.h
header file. A script generates the registry from lines in the header file
that look like:
<sp*>OID_foo,<sp*>/*<sp*>1.2.3.4<sp*>*/
The actual OID is taken to be represented by the numbers with interpolated
dots in the comment.
All other lines in the header are ignored.
The registry is queries by calling:
OID look_up_oid(const void *data, size_t datasize);
This returns a number from the registry enum representing the OID if found or
OID__NR if not.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Add a simple cpio decoder without library dependencies for the purpose
of extracting components from the initramfs blob for early kernel
uses. Intended consumers so far are microcode and ACPI override.
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/r/1349043837-22659-2-git-send-email-trenn@suse.de
Cc: Len Brown <lenb@kernel.org>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
which can adapt equally well to fast/slow devices.
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Merge tag 'writeback-proportions' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux
Pull writeback updates from Wu Fengguang:
"Use time based periods to age the writeback proportions, which can
adapt equally well to fast/slow devices."
Fix up trivial conflict in comment in fs/sync.c
* tag 'writeback-proportions' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux:
writeback: Fix some comment errors
block: Convert BDI proportion calculations to flexible proportions
lib: Fix possible deadlock in flexible proportion code
lib: Proportions with flexible period
Merge Andrew's first set of patches:
"Non-MM patches:
- lots of misc bits
- tree-wide have_clk() cleanups
- quite a lot of printk tweaks. I draw your attention to "printk:
convert the format for KERN_<LEVEL> to a 2 byte pattern" which
looks a bit scary. But afaict it's solid.
- backlight updates
- lib/ feature work (notably the addition and use of memweight())
- checkpatch updates
- rtc updates
- nilfs updates
- fatfs updates (partial, still waiting for acks)
- kdump, proc, fork, IPC, sysctl, taskstats, pps, etc
- new fault-injection feature work"
* Merge emailed patches from Andrew Morton <akpm@linux-foundation.org>: (128 commits)
drivers/misc/lkdtm.c: fix missing allocation failure check
lib/scatterlist: do not re-write gfp_flags in __sg_alloc_table()
fault-injection: add tool to run command with failslab or fail_page_alloc
fault-injection: add selftests for cpu and memory hotplug
powerpc: pSeries reconfig notifier error injection module
memory: memory notifier error injection module
PM: PM notifier error injection module
cpu: rewrite cpu-notifier-error-inject module
fault-injection: notifier error injection
c/r: fcntl: add F_GETOWNER_UIDS option
resource: make sure requested range is included in the root range
include/linux/aio.h: cpp->C conversions
fs: cachefiles: add support for large files in filesystem caching
pps: return PTR_ERR on error in device_create
taskstats: check nla_reserve() return
sysctl: suppress kmemleak messages
ipc: use Kconfig options for __ARCH_WANT_[COMPAT_]IPC_PARSE_VERSION
ipc: compat: use signed size_t types for msgsnd and msgrcv
ipc: allow compat IPC version field parsing if !ARCH_WANT_OLD_COMPAT_IPC
ipc: add COMPAT_SHMLBA support
...
This provides the ability to inject artifical errors to pSeries reconfig
notifier chain callbacks. It is controlled through debugfs interface
under /sys/kernel/debug/notifier-error-inject/pSeries-reconfig
If the notifier call chain should be failed with some events
notified, write the error code to "actions/<notifier event>/error".
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Greg KH <greg@kroah.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Dave Jones <davej@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This provides the ability to inject artifical errors to memory hotplug
notifier chain callbacks. It is controlled through debugfs interface
under /sys/kernel/debug/notifier-error-inject/memory
If the notifier call chain should be failed with some events notified,
write the error code to "actions/<notifier event>/error".
Example: Inject memory hotplug offline error (-12 == -ENOMEM)
# cd /sys/kernel/debug/notifier-error-inject/memory
# echo -12 > actions/MEM_GOING_OFFLINE/error
# echo offline > /sys/devices/system/memory/memoryXXX/state
bash: echo: write error: Cannot allocate memory
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Greg KH <greg@kroah.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Dave Jones <davej@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This provides the ability to inject artifical errors to PM notifier chain
callbacks. It is controlled through debugfs interface under
/sys/kernel/debug/notifier-error-inject/pm
Each of the files in "error" directory represents an event which can be
failed and contains the error code. If the notifier call chain should be
failed with some events notified, write the error code to the files.
If the notifier call chain should be failed with some events notified,
write the error code to "actions/<notifier event>/error".
Example: Inject PM suspend error (-12 = -ENOMEM)
# cd /sys/kernel/debug/notifier-error-inject/pm
# echo -12 > actions/PM_SUSPEND_PREPARE/error
# echo mem > /sys/power/state
bash: echo: write error: Cannot allocate memory
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Greg KH <greg@kroah.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Dave Jones <davej@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patchset provides kernel modules that can be used to test the error
handling of notifier call chain failures by injecting artifical errors to
the following notifier chain callbacks.
* CPU notifier
* PM notifier
* memory hotplug notifier
* powerpc pSeries reconfig notifier
Example: Inject CPU offline error (-1 == -EPERM)
# cd /sys/kernel/debug/notifier-error-inject/cpu
# echo -1 > actions/CPU_DOWN_PREPARE/error
# echo 0 > /sys/devices/system/cpu/cpu1/online
bash: echo: write error: Operation not permitted
The patchset also adds cpu and memory hotplug tests to
tools/testing/selftests These tests first do simple online and offline
test and then do fault injection tests if notifier error injection
module is available.
This patch:
The notifier error injection provides the ability to inject artifical
errors to specified notifier chain callbacks. It is useful to test the
error handling of notifier call chain failures.
This adds common basic functions to define which type of events can be
fail and to initialize the debugfs interface to control what error code
should be returned and which event should be failed.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Greg KH <greg@kroah.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Dave Jones <davej@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
memweight() is the function that counts the total number of bits set in
memory area. Unlike bitmap_weight(), memweight() takes pointer and size
in bytes to specify a memory area which does not need to be aligned to
long-word boundary.
[akpm@linux-foundation.org: rename `w' to `ret']
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Anders Larsen <al@alarsen.net>
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Cc: Tony Luck <tony.luck@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
libfdt is part of the device tree support in scripts/dtc/libfdt. For
some platforms that use the Device Tree, we want to be able to edit
the flattened device tree form.
We don't want to burden kernel builds that do not require it, so we
gate compilation of libfdt files with CONFIG_LIBFDT. So if it is
needed, you need to do this in your Kconfig:
select LIBFDT
And in the Makefile of the code using libfdt something like:
ccflags-y := -I$(src)/../../../scripts/dtc/libfdt
Signed-off-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: devicetree-discuss@lists.ozlabs.org
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: linux-kernel@vger.kernel.org
Acked-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Implement code computing proportions of events of different type (like code in
lib/proportions.c) but allowing periods to have different lengths. This allows
us to have aging periods of fixed wallclock time which gives better proportion
estimates given the hugely varying throughput of different devices - previous
measuring of aging period by number of events has the problem that a reasonable
period length for a system with low-end USB stick is not a reasonable period
length for a system with high-end storage array resulting either in too slow
proportion updates or too fluctuating proportion updates.
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
This makes <asm/word-at-a-time.h> actually live up to its promise of
allowing architectures to help tune the string functions that do their
work a word at a time.
David had already taken the x86 strncpy_from_user() function, modified
it to work on sparc, and then done the extra work to make it generically
useful. This then expands on that work by making x86 use that generic
version, completing the circle.
But more importantly, it fixes up the word-at-a-time interfaces so that
it's now easy to also support things like strnlen_user(), and pretty
much most random string functions.
David reports that it all works fine on sparc, and Jonas Bonn reported
that an earlier version of this worked on OpenRISC too. It's pretty
easy for architectures to add support for this and just replace their
private versions with the generic code.
* generic-string-functions:
sparc: use the new generic strnlen_user() function
x86: use the new generic strnlen_user() function
lib: add generic strnlen_user() function
word-at-a-time: make the interfaces truly generic
x86: use generic strncpy_from_user routine
A number of devices are using a common register layout, this adds support
code for it in lib/stmp_device.c so we do not need to duplicate it in
each driver.
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Merge tag 'stmp-dev' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull arm-soc stmp-dev library code from Olof Johansson:
"A number of devices are using a common register layout, this adds
support code for it in lib/stmp_device.c so we do not need to
duplicate it in each driver."
Fix up trivial conflicts in drivers/i2c/busses/i2c-mxs.c and
lib/Makefile
* tag 'stmp-dev' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
i2c: mxs: use global reset function
lib: add support for stmp-style devices
This adds a new generic optimized strnlen_user() function that uses the
<asm/word-at-a-time.h> infrastructure to portably do efficient string
handling.
In many ways, strnlen is much simpler than strncpy, and in particular we
can always pre-align the words we load from memory. That means that all
the worries about alignment etc are a non-issue, so this one can easily
be used on any architecture. You obviously do have to do the
appropriate word-at-a-time.h macros.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull sparc changes from David S. Miller:
"This has the generic strncpy_from_user() implementation architectures
can now use, which we've been developing on linux-arch over the past
few days.
For good measure I ran both a 32-bit and a 64-bit glibc testsuite run,
and the latter of which pointed out an adjustment I needed to make to
sparc's user_addr_max() definition. Linus, you were right, STACK_TOP
was not the right thing to use, even on sparc itself :-)
From Sam Ravnborg, we have a conversion of sparc32 over to the common
alloc_thread_info_node(), since the aspect which originally blocked
our doing so (sun4c) has been removed."
Fix up trivial arch/sparc/Kconfig and lib/Makefile conflicts.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
sparc: Fix user_addr_max() definition.
lib: Sparc's strncpy_from_user is generic enough, move under lib/
kernel: Move REPEAT_BYTE definition into linux/kernel.h
sparc: Increase portability of strncpy_from_user() implementation.
sparc: Optimize strncpy_from_user() zero byte search.
sparc: Add full proper error handling to strncpy_from_user().
sparc32: use the common implementation of alloc_thread_info_node()
To use this, an architecture simply needs to:
1) Provide a user_addr_max() implementation via asm/uaccess.h
2) Add "select GENERIC_STRNCPY_FROM_USER" to their arch Kcnfig
3) Remove the existing strncpy_from_user() implementation and symbol
exports their architecture had.
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: David Howells <dhowells@redhat.com>
add LPDDR2 data from the JEDEC spec JESD209-2. The data
includes:
1. Addressing information for LPDDR2 memories of different
densities and types(S2/S4)
2. AC timing data.
This data will useful for memory controller device drivers.
Right now this is used by the TI EMIF SDRAM controller
driver.
Signed-off-by: Aneesh V <aneesh@ti.com>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: Benoit Cousson <b-cousson@ti.com>
[santosh.shilimkar@ti.com: Moved to drivers/memory from drivers/misc]
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
MX23/28 use IP cores which follow a register layout I have first seen on
STMP3xxx SoCs. In this layout, every register actually has four u32:
1.) to store a value directly
2.) a SET register where every 1-bit sets the corresponding bit,
others are unaffected
3.) same with a CLR register
4.) same with a TOG (toggle) register
Also, the 2 MSBs in register 0 are always the same and can be used to reset
the IP core.
All this is strictly speaking not mach-specific (but IP core specific) and,
thus, doesn't need to be in mach-mxs/include. At least mx6 also uses IP cores
following this stmp-style. So:
Introduce a stmp-style device, put the code and defines for that in a public
place (lib/), and let drivers for stmp-style devices select that code.
To avoid regressions and ease reviewing, the actual code is simply copied from
mach-mxs. It definately wants updates, but those need a seperate patch series.
Voila, mach dependency gone, reusable code introduced. Note that I didn't
remove the duplicated code from mach-mxs yet, first the drivers have to be
converted.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Dong Aisheng <dong.aisheng@linaro.org>
Both sparc 32-bit's software divide assembler and MPILIB provide
clz_tab[] with identical contents.
Break it out into a seperate object file and select it when
SPARC32 or MPILIB is set.
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: James Morris <jmorris@namei.org>
It was reported that DIGSIG is confusing name for digital signature
module. It was suggested to rename DIGSIG to SIGNATURE.
Requested-by: Linus Torvalds <torvalds@linux-foundation.org>
Suggested-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: James Morris <jmorris@namei.org>
* 'for-linus' of git://selinuxproject.org/~jmorris/linux-security: (32 commits)
ima: fix invalid memory reference
ima: free duplicate measurement memory
security: update security_file_mmap() docs
selinux: Casting (void *) value returned by kmalloc is useless
apparmor: fix module parameter handling
Security: tomoyo: add .gitignore file
tomoyo: add missing rcu_dereference()
apparmor: add missing rcu_dereference()
evm: prevent racing during tfm allocation
evm: key must be set once during initialization
mpi/mpi-mpow: NULL dereference on allocation failure
digsig: build dependency fix
KEYS: Give key types their own lockdep class for key->sem
TPM: fix transmit_cmd error logic
TPM: NSC and TIS drivers X86 dependency fix
TPM: Export wait_for_stat for other vendor specific drivers
TPM: Use vendor specific function for status probe
tpm_tis: add delay after aborting command
tpm_tis: Check return code from getting timeouts/durations
tpm: Introduce function to poll for result of self test
...
Fix up trivial conflict in lib/Makefile due to addition of CONFIG_MPI
and SIGSIG next to CONFIG_DQL addition.
Many architectures don't want to pull in iomap.c,
so they ended up duplicating pci_iomap from that file.
That function isn't trivial, and we are going to modify it
https://lkml.org/lkml/2011/11/14/183
so the duplication hurts.
This reduces the scope of the problem significantly,
by moving pci_iomap to a separate file and
referencing that from all architectures.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
lib: use generic pci_iomap on all architectures
Many architectures don't want to pull in iomap.c,
so they ended up duplicating pci_iomap from that file.
That function isn't trivial, and we are going to modify it
https://lkml.org/lkml/2011/11/14/183
so the duplication hurts.
This reduces the scope of the problem significantly,
by moving pci_iomap to a separate file and
referencing that from all architectures.
* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
alpha: drop pci_iomap/pci_iounmap from pci-noop.c
mn10300: switch to GENERIC_PCI_IOMAP
mn10300: add missing __iomap markers
frv: switch to GENERIC_PCI_IOMAP
tile: switch to GENERIC_PCI_IOMAP
tile: don't panic on iomap
sparc: switch to GENERIC_PCI_IOMAP
sh: switch to GENERIC_PCI_IOMAP
powerpc: switch to GENERIC_PCI_IOMAP
parisc: switch to GENERIC_PCI_IOMAP
mips: switch to GENERIC_PCI_IOMAP
microblaze: switch to GENERIC_PCI_IOMAP
arm: switch to GENERIC_PCI_IOMAP
alpha: switch to GENERIC_PCI_IOMAP
lib: add GENERIC_PCI_IOMAP
lib: move GENERIC_IOMAP to lib/Kconfig
Fix up trivial conflicts due to changes nearby in arch/{m68k,score}/Kconfig
* 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (73 commits)
arm: fix up some samsung merge sysdev conversion problems
firmware: Fix an oops on reading fw_priv->fw in sysfs loading file
Drivers:hv: Fix a bug in vmbus_driver_unregister()
driver core: remove __must_check from device_create_file
debugfs: add missing #ifdef HAS_IOMEM
arm: time.h: remove device.h #include
driver-core: remove sysdev.h usage.
clockevents: remove sysdev.h
arm: convert sysdev_class to a regular subsystem
arm: leds: convert sysdev_class to a regular subsystem
kobject: remove kset_find_obj_hinted()
m86k: gpio - convert sysdev_class to a regular subsystem
mips: txx9_sram - convert sysdev_class to a regular subsystem
mips: 7segled - convert sysdev_class to a regular subsystem
sh: dma - convert sysdev_class to a regular subsystem
sh: intc - convert sysdev_class to a regular subsystem
power: suspend - convert sysdev_class to a regular subsystem
power: qe_ic - convert sysdev_class to a regular subsystem
power: cmm - convert sysdev_class to a regular subsystem
s390: time - convert sysdev_class to a regular subsystem
...
Fix up conflicts with 'struct sysdev' removal from various platform
drivers that got changed:
- arch/arm/mach-exynos/cpu.c
- arch/arm/mach-exynos/irq-eint.c
- arch/arm/mach-s3c64xx/common.c
- arch/arm/mach-s3c64xx/cpu.c
- arch/arm/mach-s5p64x0/cpu.c
- arch/arm/mach-s5pv210/common.c
- arch/arm/plat-samsung/include/plat/cpu.h
- arch/powerpc/kernel/sysfs.c
and fix up cpu_is_hotpluggable() as per Greg in include/linux/cpu.h
These are tiny functions, there's no point in having them out-of-line.
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-8eccvi2ur2fzgi00xdjlbf5z@git.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Implementation of dynamic queue limits (dql). This is a libary which
allows a queue limit to be dynamically managed. The goal of dql is
to set the queue limit, number of objects to the queue, to be minimized
without allowing the queue to be starved.
dql would be used with a queue which has these properties:
1) Objects are queued up to some limit which can be expressed as a
count of objects.
2) Periodically a completion process executes which retires consumed
objects.
3) Starvation occurs when limit has been reached, all queued data has
actually been consumed but completion processing has not yet run,
so queuing new data is blocked.
4) Minimizing the amount of queued data is desirable.
A canonical example of such a queue would be a NIC HW transmit queue.
The queue limit is dynamic, it will increase or decrease over time
depending on the workload. The queue limit is recalculated each time
completion processing is done. Increases occur when the queue is
starved and can exponentially increase over successive intervals.
Decreases occur when more data is being maintained in the queue than
needed to prevent starvation. The number of extra objects, or "slack",
is measured over successive intervals, and to avoid hysteresis the
limit is only reduced by the miminum slack seen over a configurable
time period.
dql API provides routines to manage the queue:
- dql_init is called to intialize the dql structure
- dql_reset is called to reset dynamic values
- dql_queued called when objects are being enqueued
- dql_avail returns availability in the queue
- dql_completed is called when objects have be consumed in the queue
Configuration consists of:
- max_limit, maximum limit
- min_limit, minimum limit
- slack_hold_time, time to measure instances of slack before reducing
queue limit
Signed-off-by: Tom Herbert <therbert@google.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Many architectures want a generic pci_iomap but
not the rest of iomap.c. Split that to a separate .c
file and add a new config symbol. select automatically
by GENERIC_IOMAP.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This patch implements RSA digital signature verification using GnuPG library.
The format of the signature and the public key is defined by their respective
headers. The signature header contains version information, algorithm,
and keyid, which was used to generate the signature.
The key header contains version and algorythim type.
The payload of the signature and the key are multi-precision integers.
The signing and key management utilities evm-utils provide functionality
to generate signatures and load keys into the kernel keyring.
When the key is added to the kernel keyring, the keyid defines the name
of the key.
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Adds the multi-precision-integer maths library which was originally taken
from GnuPG and ported to the kernel by (among others) David Howells.
This version is taken from Fedora kernel 2.6.32-71.14.1.el6.
The difference is that checkpatch reported errors and warnings have been fixed.
This library is used to implemenet RSA digital signature verification
used in IMA/EVM integrity protection subsystem.
Due to patch size limitation, the patch is divided into 4 parts.
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Because llist code will be used in performance critical scheduler
code path, make llist_add() and llist_del_all() inline to avoid
function calling overhead and related 'glue' overhead.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1315461646-1379-2-git-send-email-ying.huang@intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
If there are no builtin users of find_next_bit_le() and
find_next_zero_bit_le(), these functions are not present in the kernel
image, causing m68k allmodconfig to fail with:
ERROR: "find_next_zero_bit_le" [fs/ufs/ufs.ko] undefined!
ERROR: "find_next_bit_le" [fs/udf/udf.ko] undefined!
...
This started to happen after commit 171d809df1 ("m68k: merge mmu and
non-mmu bitops.h"), as m68k had its own inline versions before.
commit 63e424c844 ("arch: remove CONFIG_GENERIC_FIND_{NEXT_BIT,
BIT_LE, LAST_BIT}") added find_last_bit.o to obj-y (so it's always
included), but find_next_bit.o to lib-y (so it gets removed by the
linker if there are no builtin users).
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Greg Ungerer <gerg@uclinux.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Some trivial conflicts due to other various merges
adding to the end of common lists sooner than this one.
arch/ia64/Kconfig
arch/powerpc/Kconfig
arch/x86/Kconfig
lib/Kconfig
lib/Makefile
Signed-off-by: Len Brown <len.brown@intel.com>
Cmpxchg is used to implement adding new entry to the list, deleting
all entries from the list, deleting first entry of the list and some
other operations.
Because this is a single list, so the tail can not be accessed in O(1).
If there are multiple producers and multiple consumers, llist_add can
be used in producers and llist_del_all can be used in consumers. They
can work simultaneously without lock. But llist_del_first can not be
used here. Because llist_del_first depends on list->first->next does
not changed if list->first is not changed during its operation, but
llist_del_first, llist_add, llist_add (or llist_del_all, llist_add,
llist_add) sequence in another consumer may violate that.
If there are multiple producers and one consumer, llist_add can be
used in producers and llist_del_all or llist_del_first can be used in
the consumer.
This can be summarized as follow:
| add | del_first | del_all
add | - | - | -
del_first | | L | L
del_all | | | -
Where "-" stands for no lock is needed, while "L" stands for lock is
needed.
The list entries deleted via llist_del_all can be traversed with
traversing function such as llist_for_each etc. But the list entries
can not be traversed safely before deleted from the list. The order
of deleted entries is from the newest to the oldest added one. If you
want to traverse from the oldest to the newest, you must reverse the
order by yourself before traversing.
The basic atomic operation of this list is cmpxchg on long. On
architectures that don't have NMI-safe cmpxchg implementation, the
list can NOT be used in NMI handler. So code uses the list in NMI
handler should depend on CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
The brcm80211 driver in the staging tree has a cordic function to
determine cosine and sine for a given angle. Feedback received from
John Linville suggested that these kind of functions should be made
available to others as a library function in the kernel tree. The
b43 driver also has a cordic angle calculation implemented.
Cc: linux-kernel@vger.kernel.org
Cc: linux-wireless@vger.kernel.org
Cc: "John W. Linville" <linville@tuxdriver.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Dan Carpenter <error27@gmail.com>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: Larry Finger <Larry.Finger@lwfinger.net>
Reviewed-by: Roland Vossen <rvossen@broadcom.com>
Reviewed-by: Henry Ptasinski <henryp@broadcom.com>
Reviewed-by: Franky (Zhenhui) Lin <frankyl@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Matthew Garrett
Stefani Seibold
Linus Torvalds
Oleg Nesterov
Benjamin Herrenschmidt
Tim Gardner
Bill Pemberton
Michel Lespinasse
David Howells
H. Peter Anvin
Akinobu Mita
David Daney
Jan Kara
David S. Miller
Aneesh V
Wolfram Sang
Dmitry Kasatkin
Peter Zijlstra
Tom Herbert
Michael S. Tsirkin
Huang Ying
Geert Uytterhoeven
Len Brown
John W. Linville
Arend van Spriel