This patch adds support for dumping a process' (classic BPF) seccomp
filters via ptrace.
PTRACE_SECCOMP_GET_FILTER allows the tracer to dump the user's classic BPF
seccomp filters. addr should be an integer which represents the ith seccomp
filter (0 is the most recently installed filter). data should be a struct
sock_filter * with enough room for the ith filter, or NULL, in which case
the filter is not saved. The return value for this command is the number of
BPF instructions the program represents, or negative in the case of errors.
Command specific errors are ENOENT: which indicates that there is no ith
filter in this seccomp tree, and EMEDIUMTYPE, which indicates that the ith
filter was not installed as a classic BPF filter.
A caveat with this approach is that there is no way to get explicitly at
the heirarchy of seccomp filters, and users need to memcmp() filters to
decide which are inherited. This means that a task which installs two of
the same filter can potentially confuse users of this interface.
v2: * make save_orig const
* check that the orig_prog exists (not necessary right now, but when
grows eBPF support it will be)
* s/n/filter_off and make it an unsigned long to match ptrace
* count "down" the tree instead of "up" when passing a filter offset
v3: * don't take the current task's lock for inspecting its seccomp mode
* use a 0x42** constant for the ptrace command value
v4: * don't copy to userspace while holding spinlocks
v5: * add another condition to WARN_ON
v6: * rebase on net-next
Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>
Acked-by: Kees Cook <keescook@chromium.org>
CC: Will Drewry <wad@chromium.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
CC: Andy Lutomirski <luto@amacapital.net>
CC: Pavel Emelyanov <xemul@parallels.com>
CC: Serge E. Hallyn <serge.hallyn@ubuntu.com>
CC: Alexei Starovoitov <ast@kernel.org>
CC: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Device statistics can be gathered on-demand. This adds the qed support for
reading the statistics [both function and port] from the device, and adds
to the public API a method for requesting the current statistics.
Signed-off-by: Manish Chopra <Manish.Chopra@qlogic.com>
Signed-off-by: Yuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: Ariel Elior <Ariel.Elior@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Physical link is handled by the management Firmware.
This patch lays the infrastructure for attention handling in the driver,
as link change notifications arrive via async. attentions,
as well the handling of such notifications.
This patch also extends the API with the protocol drivers by adding
registered callbacks which the protocol driver passes to qed in order
to be notified of async. events originating from the FW/HW.
Signed-off-by: Yuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: Ariel Elior <Ariel.Elior@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds to the qed the support to configure various L2 elements,
such as channels and basic filtering conditions.
It also enhances its public API to allow qede to later utilize this
functionality.
Signed-off-by: Manish Chopra <Manish.Chopra@qlogic.com>
Signed-off-by: Yuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: Ariel Elior <Ariel.Elior@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds a public API for a network driver to work on top of QED.
The interface itself is very minimal - it's mostly infrastructure, as the
only content it has after this patch is a query for HW-based information
required for the creation of a network interface [I.e., no actual
protocol-specific configurations are supported].
Signed-off-by: Manish Chopra <Manish.Chopra@qlogic.com>
Signed-off-by: Yuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: Ariel Elior <Ariel.Elior@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The Qlogic Everest Driver is the backend module for the QL4xxx ethernet
products by Qlogic.
This module serves two main purposes:
1. It's responsible to contain all the common code that will be shared
between the various drivers that would be used with said line of
products. Flows such as chip initialization and de-initialization
fall under this category.
2. It would abstract the protocol-specific HW & FW components, allowing
the protocol drivers to have a clean APIs which is detached in its
slowpath configuration from the actual HSI.
This adds a very basic module without any protocol-specific bits.
I.e., this adds a basic implementation that almost entirely falls under
the first category.
Signed-off-by: Yuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: Ariel Elior <Ariel.Elior@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Debugging input devices, specifically laptop touchpads, can be tricky
without having the physical device handy. Here we try to remedy that
with userio. This module allows an application to connect to a character
device provided by the kernel, and emulate any serio device. In
combination with userspace programs that can record PS/2 devices and
replay them through the /dev/userio device, this allows developers to
debug driver issues on the PS/2 level with devices simply by requesting
a recording from the user experiencing the issue without having to have
the physical hardware in front of them.
Signed-off-by: Stephen Chandler Paul <cpaul@redhat.com>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Add spi_register_driver helper macro that adds THIS_MODULE to
spi_driver for the registering driver. We rename and modify
the existing spi_register_driver to enable this.
Signed-off-by: Andrew F. Davis <afd@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This is a major overhaul of the clk-qoriq driver, which I'm merging
via PPC with Stephen Boyd's ack in order to apply subsequent PPC patches
that depend on it.
For pinctrl the "default" state is applied to pins before the driver's
probe function is called. This is normally a sensible thing to do,
but in some cases can cause problems. That's because the pins will
change state before the driver is given a chance to program how those
pins should behave.
As an example you might have a regulator that is controlled by a PWM
(output high = high voltage, output low = low voltage). The firmware
might leave this pin as driven high. If we allow the driver core to
reconfigure this pin as a PWM pin before the PWM's probe function runs
then you might end up running at too low of a voltage while we probe.
Let's introudce a new "init" state. If this is defined we'll set
pinctrl to this state before probe and then "default" after probe
(unless the driver explicitly changed states already).
An alternative idea that was thought of was to use the pre-existing
"sleep" or "idle" states and add a boolean property that we should
start in that mode. This was not done because the "init" state is
needed for correctness and those other states are only present (and
only transitioned in to and out of) when (optional) power management
is enabled.
Changes in v3:
- Moved declarations to pinctrl/devinfo.h
- Fixed author/SoB
Changes in v2:
- Added comment to pinctrl_init_done() as per Linus W.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tested-by: Caesar Wang <wxt@rock-chips.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The mmc_execute_tuning() has already prepared the opcode,
there is no need to prepare it again at mmc_send_tuning(),
and, there is a BUG of mmc_send_tuning() to determine the opcode
by bus width, assume eMMC was running at HS200, 4bit mode,
then the mmc_send_tuning() will overwrite the opcode from CMD21
to CMD19, then got error.
in addition, extend an argument of "cmd_error" to allow getting
if there was cmd error when tune response.
Signed-off-by: Chaotian Jing <chaotian.jing@mediatek.com>
[Ulf: Rebased patch]
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
While unifying how blkcg stats are collected, 77ea733884 ("blkcg:
move io_service_bytes and io_serviced stats into blkcg_gq")
incorrectly used bio->flags instead of bio->rw to tell the IO type.
This made IOs to be accounted as the wrong type. Fix it.
Signed-off-by: Tejun Heo <tj@kernel.org>
Fixes: 77ea733884 ("blkcg: move io_service_bytes and io_serviced stats into blkcg_gq")
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Michael Grzeschik says:
====================
This series includes code simplifaction. The main changes are the correct
xceiver handling (enable/disable) of the com20020 cards. The driver now handles
link status change detection. The EAE PCI-ARCNET cards now make use of the
rotary encoded subdevice indexing and got support for led triggers on transmit
and reconnection events.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix safety checks for bpf_perf_event_read():
- only non-inherited events can be added to perf_event_array map
(do this check statically at map insertion time)
- dynamically check that event is local and !pmu->count
Otherwise buggy bpf program can cause kernel splat.
Also fix error path after perf_event_attrs()
and remove redundant 'extern'.
Fixes: 35578d7984 ("bpf: Implement function bpf_perf_event_read() that get the selected hardware PMU conuter")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Wang Nan <wangnan0@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This driver adds the support of I2C-based Marvell NFC controller.
Signed-off-by: Vincent Cuissard <cuissard@marvell.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
In order to align with st21nfca, dts configuration properties
ese_present and uicc_present are made available in st-nci driver.
So far, in early development firmware, because
nci_nfcee_mode_set(DISABLE) was not supported we had to try to
enable it during the secure element discovery phase.
After several trials on commercial and qualified firmware it appears
that nci_nfcee_mode_set(ENABLE) and nci_nfcee_mode_set(DISABLE) are
properly supported.
Such feature also help us to eventually save some time (~5ms) when
only one secure element is connected.
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
With the old binding and driver architecture we had many issues:
No way to assign eDMA channels to event queues, thus not able to tune the
system by moving specific DMA channels to low/high priority servicing. We
moved the cyclic channels to high priority within the code, but that was
just a workaround to this issue.
Memcopy was fundamentally broken: even if the driver scanned the DT/devices
in the booted system for direct DMA users (which is not effective when the
events are going through a crossbar) and created a map of 'used' channels,
this information was not really usable. Since via dmaengien API the eDMA
driver will be called with _some_ channel number, we would try to request
this channel when any channel is requested for memcpy. By luck we got
channel which is not used by any device most of the time so things worked,
but if a device would have been using the given channel, but not requested
it, the memcpy channel would have been waiting for HW event.
The old code had the am33xx/am43xx DMA event router handling embedded. This
should have been done in a separate driver since it is not part of the
actual eDMA IP.
There were no way to 'lock' PaRAM slots to be used by the DSP for example
when booting with DT.
In DT boot the edma node used more than one hwmod which is not a good
practice and the kernel prints warning because of this.
With the new bindings and the changes in the driver we can:
- No regression with Legacy binding and non DT boot
- DMA channels can be assigned to any TC (to set priority)
- PaRAM slots can be reserved for other cores to use
- Dynamic power management for CC and TCs, if only TC0 is used all other TC
can be powered down for example
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The point in providing an inline version of intel_svm_bind_mm() which
just returns -ENOSYS is that people are supposed to be able to *use* it
and just see that it fails. So we need to let them have a definition of
struct svm_dev_ops (and the flags) too.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Add clk_hw_is_enabled() to the provider APIs so clk providers can
use a struct clk_hw instead of a struct clk to check if a clk is
enabled or not.
Signed-off-by: Joachim Eastwood <manabian@gmail.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Compiling the versatile clock driver with COMPILE_TEST=y and CONFIG_OF=n
leads to the following error:
drivers/clk/versatile/clk-sp810.c: In function 'clk_sp810_of_setup':
drivers/clk/versatile/clk-sp810.c:103:6: error: implicit declaration of
function 'of_clk_parent_fill' [-Werror=implicit-function-declaration]
Silence it by providing stubs APIs for of_clk_parent_fill().
Throw in a stub for of_clk_get_parent_count() too because we're
in the area.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Cc: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
DesignWare MMC Controller can supports two types of DMA
mode: external dma and internal dma. We get a RK312x platform
integrated dw_mmc and ARM pl330 dma controller. This patch add
edmac ops to support these platforms. I've tested it on RK31xx
platform with edmac mode and RK3288 platform with idmac mode.
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This adds logic to the MMC core to set VQMMC. This is expected to be
called by MMC drivers like dw_mmc as part of (or instead of) their
start_signal_voltage_switch() callback.
A few notes:
* When setting the signal voltage to 3.3V we do our best to make VQMMC
and VMMC match. It's been reported that this makes some old cards
happy since they were tested back in the day before UHS when VQMMC
and VMMC were provided by the same regulator. A nice side effect of
this is that we don't end up on the hairy edge of VQMMC (2.7V),
which some EEs claim is a little too close to the minimum for
comfort.
This is done in two steps. At first we try to find a VQMMC within
a 0.3V tolerance of VMMC and if this is not supported by the
supplying regulator we try to find a suitable voltage within the
whole 2.7V-3.6V area of the spec.
* The two step approach is currently necessary, as the used
regulator_set_voltage_triplet(min, target, max) uses a simple
implementation that just tries two basic steps:
regulator_set_voltage(target, max);
regulator_set_voltage(min, target);
So with only one step with 2.7-3.6V borders, if a suitable voltage
is a bit below VMMC, we would directly get the lowest 2.7V
which some boards (like Rockchips) don't like at all.
* When setting the signal voltage to 1.8V or 1.2V we aim for that
specific voltage instead of picking the lowest one in the range.
* We very purposely don't print errors in mmc_regulator_set_vqmmc().
There are cases where the MMC core will try several different
voltages and we don't want to pollute the logs.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
MMC_CLKGATE was once invented to save power by gating the bus clock at
request inactivity. At that time it served its purpose. The modern way to
deal with power saving for these scenarios, is by using runtime PM.
Nowadays, several host drivers have deployed runtime PM, but for those
that haven't and which still cares power saving at request inactivity,
it's certainly time to deploy runtime PM as it has been around for several
years now.
To simplify code to mmc core and thus decrease maintenance efforts, this
patch removes all code related to MMC_CLKGATE.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
As there are no users of the __mmc_switch() API, except for the mmc core
itself, let's convert it from an exported function into an internal.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Some Arizona devices have a hardware ANC block present. This patch adds
the registers necessary to configure this hardware block.
Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
On Odroid XU3 board (with S2MPS11 PMIC) the PWRHOLD bit in CTRL1
register must be manually set to 0 before initiating power off sequence.
One of usual power down methods for Exynos based devices looks like:
1. PWRHOLD pin of PMIC is connected to PSHOLD of Exynos SoC.
2. Exynos holds up this pin during system operation.
3. ACOKB pin of PMIC is pulled up to VBATT and optionally to pin in
other device.
4. When PWRHOLD/PSHOLD goes low, the PMIC will turn off the power if
ACOKB goes high.
On Odroid XU3 family the difference is in (3) - the ACOKB is grounded.
This means that PMIC must manually set PWRHOLD field to low and then
wait for signal from Application Processor (the usual change in
PWRHOLD/PSHOLD pin will actually cut off the power).
The patch adds respective binding allowing Odroid XU3 device to be
powered off.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com>
Reported-by: Anand Moon <linux.amoon@gmail.com>
Tested-by: Anand Moon <linux.amoon@gmail.com>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
There is at least one board on the market, i.e. Intel Galileo Gen2, that uses
_ADR to distinguish the devices under one actual device. Due to this we have to
improve the quirk in the MFD core to handle that board.
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
ASoC: Updates for v4.4
Not much core work here, a few small tweaks to interfaces but mainly the
changes here are driver ones. Highlights include:
- Updates to the topology userspace interface
- Big updates to the Renesas support from Morimoto-san
- Most of the support for Intel Sky Lake systems.
- New drivers for Asahi Kasei Microdevices AK4613, Allwinnner A10,
Cirrus Logic WM8998, Dialog DA7219, Nuvoton NAU8825 and Rockchip
S/PDIF.
- A new driver for the Atmel Class D speaker drivers
The EAE PLX-PCI card has special leds on the the main io pci resource
bar. This patch adds support to trigger the conflict and data leds with
the packages.
Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Currently when the system is trying to uninstall the ACPI interrupt
handler, it uses acpi_gbl_FADT.sci_interrupt as the IRQ number.
However, the IRQ number that the ACPI interrupt handled is installed
for comes from acpi_gsi_to_irq() and that is the number that should
be used for the handler removal.
Fix this problem by using the mapped IRQ returned from acpi_gsi_to_irq()
as appropriate.
Cc: All applicable <stable@vger.kernel.org>
Acked-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Add the necessary hooks to use the pids loaded in set_event_pid to filter
all the events enabled in the tracing instance that match the pids listed.
Two probes are added to both sched_switch and sched_wakeup tracepoints to be
called before other probes are called and after the other probes are called.
The first is used to set the necessary flags to let the probes know to test
if they should be traced or not.
The sched_switch pre probe will set the "ignore_pid" flag if neither the
previous or next task has a matching pid.
The sched_switch probe will set the "ignore_pid" flag if the next task
does not match the matching pid.
The pre probe allows for probes tracing sched_switch to be traced if
necessary.
The sched_wakeup pre probe will set the "ignore_pid" flag if neither the
current task nor the wakee task has a matching pid.
The sched_wakeup post probe will set the "ignore_pid" flag if the current
task does not have a matching pid.
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
In order to guarantee that a probe will be called before other probes that
are attached to a tracepoint, there needs to be a mechanism to provide
priority of one probe over the others.
Adding a prio field to the struct tracepoint_func, which lets the probes be
sorted by the priority set in the structure. If no priority is specified,
then a priority of 10 is given (this is a macro, and perhaps may be changed
in the future).
Now probes may be added to affect other probes that are attached to a
tracepoint with a guaranteed order.
One use case would be to allow tracing of tracepoints be able to filter by
pid. A special (higher priority probe) may be added to the sched_switch
tracepoint and set the necessary flags of the other tracepoints to notify
them if they should be traced or not. In case a tracepoint is enabled at the
sched_switch tracepoint too, the order of the two are not random.
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Reduced Serial Bus (RSB) is an Allwinner proprietery interface
used to communicate with PMICs and other peripheral ICs.
RSB is a two-wire push-pull serial bus that supports 1 master
device and up to 15 active slave devices.
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
* acpi-pci:
ia64/PCI/ACPI: Use common interface to support PCI host bridge
x86/PCI/ACPI: Use common interface to support PCI host bridge
ACPI/PCI: Reset acpi_root_dev->domain to 0 when pci_ignore_seg is set
PCI/ACPI: Add interface acpi_pci_root_create()
ia64/PCI: Use common struct resource_entry to replace struct iospace_resource
ia64/PCI/ACPI: Use common ACPI resource parsing interface for host bridge
ACPI/PCI: Enhance ACPI core to support sparse IO space
Add a generic fully device independent DMA buffer implementation that uses
the DMAegnine framework to perform the DMA transfers. This can be used by
converter drivers that whish to provide a DMA buffer for converters that
are connected to a DMA core that implements the DMAengine API.
Apart from allocating the buffer using iio_dmaengine_buffer_alloc() and
freeing it using iio_dmaengine_buffer_free() no additional converter driver
specific code is required when using this DMA buffer implementation.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
The traditional approach used in IIO to implement buffered capture requires
the generation of at least one interrupt per sample. In the interrupt
handler the driver reads the sample from the device and copies it to a
software buffer. This approach has a rather large per sample overhead
associated with it. And while it works fine for samplerates in the range of
up to 1000 samples per second it starts to consume a rather large share of
the available CPU processing time once we go beyond that, this is
especially true on an embedded system with limited processing power. The
regular interrupt also causes increased power consumption by not allowing
the hardware into deeper sleep states, which is something that becomes more
and more important on mobile battery powered devices.
And while the recently added watermark support mitigates some of the issues
by allowing the device to generate interrupts at a rate lower than the data
output rate, this still requires a storage buffer inside the device and
even if it exists it is only a few 100 samples deep at most.
DMA support on the other hand allows to capture multiple millions or even
more samples without any CPU interaction. This allows the CPU to either go
to sleep for longer periods or focus on other tasks which increases overall
system performance and power consumption. In addition to that some devices
might not even offer a way to read the data other than using DMA, which
makes DMA mandatory to use for them.
The tasks involved in implementing a DMA buffer can be divided into two
categories. The first category is memory buffer management (allocation,
mapping, etc.) and hooking this up the IIO buffer callbacks like read(),
enable(), disable(), etc. The second category of tasks is to setup the
DMA hardware and manage the DMA transfers. Tasks from the first category
will be very similar for all IIO drivers supporting DMA buffers, while the
tasks from the second category will be hardware specific.
This patch implements a generic infrastructure that take care of the former
tasks. It provides a set of functions that implement the standard IIO
buffer iio_buffer_access_funcs callbacks. These can either be used as is or
be overloaded and augmented with driver specific code where necessary.
For the DMA buffer support infrastructure that is introduced in this series
sample data is grouped by so called blocks. A block is the basic unit at
which data is exchanged between the application and the hardware. The
application is responsible for allocating the memory associated with the
block and then passes the block to the hardware. When the hardware has
captured the amount of samples equal to size of a block it will notify the
application, which can then read the data from the block and process it.
The block size can freely chosen (within the constraints of the hardware).
This allows to make a trade-off between latency and management overhead.
The larger the block size the lower the per sample overhead but the latency
between when the data was captured and when the application will be able to
access it increases, in a similar way smaller block sizes have a larger per
sample management overhead but a lower latency. The ideal block size thus
depends on system and application requirements.
For the time being the infrastructure only implements a simple double
buffered scheme which allocates two blocks each with half the size of the
configured buffer size. This provides basic support for capturing
continuous uninterrupted data over the existing file-IO ABI. Future
extensions to the DMA buffer infrastructure will give applications a more
fine grained control over how many blocks are allocated and the size of
each block. But this requires userspace ABI additions which are
intentionally not part of this patch and will be added separately.
Tasks of the second category need to be implemented by a device specific
driver. They can be hooked up into the generic infrastructure using two
simple callbacks, submit() and abort().
The submit() callback is used to schedule DMA transfers for blocks. Once a
DMA transfer has been completed it is expected that the buffer driver calls
iio_dma_buffer_block_done() to notify. The abort() callback is used for
stopping all pending and active DMA transfers when the buffer is disabled.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
This patch adds a enable and disable callback that is called when the
buffer is enabled/disabled. This can be used by buffer implementations that
need to do some setup or teardown work. E.g. a DMA based buffer can use
this to start/stop the DMA transfer.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
For buffers which have a fixed wake-up watermark the watermark attribute
should be read-only. Add a new FIXED_WATERMARK flag to the
struct iio_buffer_access_funcs, which can be set by a buffer
implementation.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
The existing code breaks on architectures where the L1 cache size
(L1_CACHE_BYTES) is smaller or equal the size of struct xps_map.
The new code ensures that we get at minimum one initial xps queue, or even more
as long as it fits into the next multiple of L1_CACHE_SIZE.
Signed-off-by: Helge Deller <deller@gmx.de>
Acked-by: Alexander Duyck <aduyck@mirantis.com>
Conflicts:
net/ipv6/xfrm6_output.c
net/openvswitch/flow_netlink.c
net/openvswitch/vport-gre.c
net/openvswitch/vport-vxlan.c
net/openvswitch/vport.c
net/openvswitch/vport.h
The openvswitch conflicts were overlapping changes. One was
the egress tunnel info fix in 'net' and the other was the
vport ->send() op simplification in 'net-next'.
The xfrm6_output.c conflicts was also a simplification
overlapping a bug fix.
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull block layer fixes from Jens Axboe:
"A final set of fixes for 4.3.
It is (again) bigger than I would have liked, but it's all been
through the testing mill and has been carefully reviewed by multiple
parties. Each fix is either a regression fix for this cycle, or is
marked stable. You can scold me at KS. The pull request contains:
- Three simple fixes for NVMe, fixing regressions since 4.3. From
Arnd, Christoph, and Keith.
- A single xen-blkfront fix from Cathy, fixing a NULL dereference if
an error is returned through the staste change callback.
- Fixup for some bad/sloppy code in nbd that got introduced earlier
in this cycle. From Markus Pargmann.
- A blk-mq tagset use-after-free fix from Junichi.
- A backing device lifetime fix from Tejun, fixing a crash.
- And finally, a set of regression/stable fixes for cgroup writeback
from Tejun"
* 'for-linus' of git://git.kernel.dk/linux-block:
writeback: remove broken rbtree_postorder_for_each_entry_safe() usage in cgwb_bdi_destroy()
NVMe: Fix memory leak on retried commands
block: don't release bdi while request_queue has live references
nvme: use an integer value to Linux errno values
blk-mq: fix use-after-free in blk_mq_free_tag_set()
nvme: fix 32-bit build warning
writeback: fix incorrect calculation of available memory for memcg domains
writeback: memcg dirty_throttle_control should be initialized with wb->memcg_completions
writeback: bdi_writeback iteration must not skip dying ones
writeback: fix bdi_writeback iteration in wakeup_dirtytime_writeback()
writeback: laptop_mode_timer_fn() needs rcu_read_lock() around bdi_writeback iteration
nbd: Add locking for tasks
xen-blkfront: check for null drvdata in blkback_changed (XenbusStateClosing)
