The way the mask is generated in regmap_field_init() is wrong.
Indeed, a field initialized with msb = 31 and lsb = 0 provokes a shift
overflow while calculating the mask field.
On some 32 bits architectures, such as x86, the generated mask is 0,
instead of the expected 0xffffffff.
This patch uses GENMASK() to fix the problem, as this macro is already safe
regarding shift overflow.
Signed-off-by: Maxime Coquelin <maxime.coquelin@st.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
Currently the con_id of the acquired clock is printed for debugging
purposes. But in several cases, the con_id is NULL, which doesn't
provide much debugging information when printed. These cases are:
- When explicitly passing a NULL con_id (which means the first clock
tied to the device, if available),
- When not using pm_clk_add(), but pm_clk_add_clk() (which takes a
"struct clk *" directly).
Hence print the actual clock name in addition to (and not instead of;
thanks Grygorii Strashko!) the con_id.
Note that the clock name is not available with legacy clock frameworks,
and the hex pointer address will be printed instead.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Grygorii Strashko <grygorii.strashko@linaro.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The PM Domain code uses ktime_get() to perform various latency
measurements. However, if ktime_get() is called while timekeeping is
suspended, the following warning is printed:
WARNING: CPU: 0 PID: 1340 at kernel/time/timekeeping.c:576 ktime_get+0x3
This happens when resuming the PM Domain that contains the clock events
source, which calls pm_genpd_syscore_poweron(). Chain of operations is:
timekeeping_resume()
{
clockevents_resume()
sh_cmt_clock_event_resume()
pm_genpd_syscore_poweron()
pm_genpd_sync_poweron()
genpd_syscore_switch()
genpd_power_on()
ktime_get(), but timekeeping_suspended == 1
...
timekeeping_suspended = 0;
}
Fix this by adding a "timed" parameter to genpd_power_{on,off}() and
pm_genpd_sync_power{off,on}(), to indicate whether latency measurements
are allowed. This parameter is passed as false in
genpd_syscore_switch() (i.e. during syscore suspend/resume), and true in
all other cases.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In big endian mode regmap_bulk_read gives incorrect data
for byte reads.
This is because memcpy of a single byte from an address
after full word read gives different results when
endianness differs. ie. we get little-end in LE and big-end in BE.
Signed-off-by: Arun Chandran <achandran@mvista.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
Currently, device drivers, which support both OF and ACPI,
need to call two separate APIs, of_dma_is_coherent() and
acpi_dma_is_coherent()) to determine device coherency attribute.
This patch simplifies this process by introducing a new device
property API, device_dma_is_coherent(), which calls the appropriate
interface based on the booting architecture.
Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Move the trace_device_pm_callback locations for dpm_prepare and dpm_complete
to encompass the attempt to capture the device mutex prior to callback. This
is needed by analyze_suspend to identify gaps in the trace output caused by
the delay in locking the mutex for a device.
Signed-off-by: Todd Brandt <todd.e.brandt@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
set_irq_flags is ARM specific with custom flags which have genirq
equivalents. Convert drivers to use the genirq interfaces directly, so we
can kill off set_irq_flags. The translation of flags is as follows:
IRQF_VALID -> !IRQ_NOREQUEST
IRQF_PROBE -> !IRQ_NOPROBE
IRQF_NOAUTOEN -> IRQ_NOAUTOEN
For IRQs managed by an irqdomain, the irqdomain core code handles clearing
and setting IRQ_NOREQUEST already, so there is no need to do this in
.map() functions and we can simply remove the set_irq_flags calls. Some
users also set IRQ_NOPROBE and this has been maintained although it is not
clear that is really needed. There appears to be a great deal of blind
copy and paste of this code.
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
On some simulators like GEM5, caches may not be simulated. In those
cases, the cache levels and leaves will be zero and will result in
following exception:
Unable to handle kernel NULL pointer dereference at virtual address 0040
pgd = ffffffc0008fa000
[00000040] *pgd=00000009f6807003, *pud=00000009f6807003,
*pmd=00000009f6808003, *pte=006000002c010707
Internal error: Oops: 96000005 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 1 Comm: swapper/0 Not tainted 4.1.0-rc5 #198
task: ffffffc9768a0000 ti: ffffffc9768a8000 task.ti: ffffffc9768a8000
PC is at detect_cache_attributes+0x98/0x2c8
LR is at detect_cache_attributes+0x88/0x2c8
kcalloc(0) returns a special value ZERO_SIZE_PTR which is non-NULL value
but results in fault only on any attempt to dereferencing it. So
checking for the non-NULL pointer will not suffice.
This patch checks for non-zero cache leaf nodes and returns error if
there are no cache leaves in detect_cache_attributes.
Cc: <stable@vger.kernel.org> # 3.19.x
Cc: Will Deacon <will.deacon@arm.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reported-by: William Wang <william.wang@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Failure path of platform_device_add was almost the same as
platform_device_del. Refactor same code in a function.
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
insert_resource() can fail when the resource added overlaps
(partially or fully) with another.
Device tree and AMBA devices may contain resources that overlap, so they
could not call platform_device_add (see 02bbde7849 ('Revert "of:
use platform_device_add"'))"
On the other hand, device trees are released using
platform_device_unregister(). This function calls platform_device_del(),
which calls release_resource(), that crashes when the resource has not
been added with with insert_resource. This was not an issue when the
device tree could not be modified online, but this is not the case
anymore.
This patch let the flow continue when there is an insert error, after
notifying the user with a dev_err(). r->parent is set to NULL, so
platform_device_del() knows that the resource was not added, and
therefore it should not be released.
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
platform_device_del only checks the type of the resource in order to
call release_resource.
On the other hand, platform_device_add calls insert_resource for any
resource that has a parent.
Make both code branches balanced.
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Delete jump to a label on the next line, when that label is not
used elsewhere.
A simplified version of the semantic patch that makes this change is as
follows: (http://coccinelle.lip6.fr/)
// <smpl>
@r@
identifier l;
@@
-if (...) goto l;
-l:
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Mark Brown <broonie@kernel.org>
Commit 5590f3196b ("drivers/core/of: Add symlink to device-tree from
devices with an OF node") adds the symlink `of_node` for each device
pointing to it's device tree node while creating/initialising it.
However the devicetree sysfs is created and setup in of_init which is
executed at core_initcall level. For all the devices created before
of_init, the following error is thrown:
"Error -2(-ENOENT) creating of_node link"
Like many other components in driver model, initialize the sysfs support
for OF/devicetree from driver_init so that it's ready before any devices
are created.
Fixes: 5590f3196b ("drivers/core/of: Add symlink to device-tree from
devices with an OF node")
Suggested-by: Rob Herring <robh+dt@kernel.org>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Robert Schwebel <r.schwebel@pengutronix.de>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We currently use flexible arrays with a char at the
end for the remaining internal firmware name uses.
There are two limitations with the way we use this.
Since we're using a flexible array for a string on the
struct if we wanted to use two strings it means we'd
have a disjoint means of handling the strings, one
using the flexible array, and another a char * pointer.
We're also currently not using 'const' for the string.
We wish to later extend some firmware data structures
with other string/char pointers, but we also want to be
very pedantic about const usage. Since we're going to
change things to use 'const' we might as well also address
unified way to use multiple strings on the structs.
Replace the flexible array practice for strings with
kstrdup_const() and kfree_const(), this will avoid
allocations when the vmlinux .rodata is used, and just
allocate a new proper string for us when needed. This
also means we can simplify the struct allocations by
removing the string length from the allocation size
computation, which would otherwise get even more
complicated when supporting multiple strings.
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: David Howells <dhowells@redhat.com>
Cc: Ming Lei <ming.lei@canonical.com>
Cc: Seth Forshee <seth.forshee@canonical.com>
Cc: Kyle McMartin <kyle@kernel.org>
Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When direct firmware loading is used we iterate over a list
of possible firmware paths and concatenate the desired firmware
name with each path and look for the file there. Should the
passed firmware name be too long we end up truncating the
file we want to look for, the search however is still done.
Add a check for truncation instead of looking for a
truncated firmware filename.
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ming Lei <ming.lei@canonical.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: David Howells <dhowells@redhat.com>
Cc: Kyle McMartin <kyle@kernel.org>
Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The request_firmware*() APIs uses __getname() to iterate
over the list of paths possible for firmware to be found,
the code however never checked for failure on __getname().
Although *very unlikely*, this can still happen. Add the
missing check.
There is still no checks on the concatenation of the path
and filename passed, that requires a bit more work and
subsequent patches address this. The commit that introduced
this is abb139e7 ("firmware: teach the kernel to load
firmware files directly from the filesystem").
mcgrof@ergon ~/linux (git::firmware-fixes) $ git describe --contains abb139e7
v3.7-rc1~120
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ming Lei <ming.lei@canonical.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: David Howells <dhowells@redhat.com>
Cc: Kyle McMartin <kyle@kernel.org>
Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 5590f3196b ("drivers/core/of: Add symlink to device-tree from
devices with an OF node") adds the symlink `of_node` for each device
pointing to it's device tree node while creating/initialising it.
However the devicetree sysfs is created and setup in of_init which is
executed at core_initcall level. For all the devices created before
of_init, the following error is thrown:
"Error -2(-ENOENT) creating of_node link"
Like many other components in driver model, initialize the sysfs support
for OF/devicetree from driver_init so that it's ready before any devices
are created.
Fixes: 5590f3196b ("drivers/core/of: Add symlink to device-tree from
devices with an OF node")
Suggested-by: Rob Herring <robh+dt@kernel.org>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Robert Schwebel <r.schwebel@pengutronix.de>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
s/hierarcy/hierarchy/
Maybe the typo will annoy people enough so that they add the missing
nodes to their device-tree files, but I still think this is better off
fixed.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit f2411da746 ("driver-core: add driver module asynchronous probe
support") broke build in case modules are disabled, because in this case
"struct module" is not defined and we can't dereference it. Let's define
module_requested_async_probing() helper and stub it out if modules are
disabled.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch introduces regmap_get_reg_stride() function which would
be used by the infrastructures like nvmem framework built on top of
regmap. Mostly this function would be used for sanity checks on inputs
within such infrastructure.
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
This patch introduces regmap_get_max_register() function which would be
used by the infrastructures like nvmem framework built on top of
regmap.
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Because platform_driver_probe() checks, after trying to register driver,
if there are any devices that driver successfully bound to, driver's
probe routine must be run synchronously.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are drivers that can not be probed asynchronously. One such group
is platform drivers registered with platform_driver_probe(), which
expects driver's probe routine be discarded after the driver has been
registered and initial binding attempt executed. Also
platform_driver_probe() an error when no devices were bound to the
driver, allowing failing to load such driver module altogether.
Other drivers do not work well with asynchronous probing because of
driver bug or not optimal driver organization.
To allow using such drivers even when user requests asynchronous probing
as default boot strategy, let's allow them to opt out.
Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some init systems may wish to express the desire to have device drivers
run their probe() code asynchronously. This implements support for this
and allows userspace to request async probe as a preference through a
generic shared device driver module parameter, async_probe.
Implementation for async probe is supported through a module parameter
given that since synchronous probe has been prevalent for years some
userspace might exist which relies on the fact that the device driver
will probe synchronously and the assumption that devices it provides
will be immediately available after this.
Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some devices take a long time when initializing, and not all drivers are
suited to initialize their devices when they are open. For example,
input drivers need to interrogate their devices in order to publish
device's capabilities before userspace will open them. When such drivers
are compiled into kernel they may stall entire kernel initialization.
This change allows drivers request for their probe functions to be
called asynchronously during driver and device registration (manual
binding is still synchronous). Because async_schedule is used to perform
asynchronous calls module loading will still wait for the probing to
complete.
Note that the end goal is to make the probing asynchronous by default,
so annotating drivers with PROBE_PREFER_ASYNCHRONOUS is a temporary
measure that allows us to speed up boot process while we validating and
fixing the rest of the drivers and preparing userspace.
This change is based on earlier patch by "Luis R. Rodriguez"
<mcgrof@suse.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently there is no way to query which CPUs are in nohz_full
mode from userspace.
Export the CPU list running in nohz_full mode in sysfs,
specifically in the file /sys/devices/system/cpu/nohz_full
This can be used by system management tools like libvirt,
openstack, and others to ensure proper task placement.
Signed-off-by: Rik van Riel <riel@redhat.com>
Acked-by: Mike Galbraith <umgwanakikbuti@gmail.com>
Acked-by: Chris Metcalf <cmetcalf@ezchip.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
After system bootup, there is no totally reliable way to see
which CPUs are isolated, because the kernel may modify the
CPUs specified on the isolcpus= kernel command line option.
Export the CPU list that actually got isolated in sysfs,
specifically in the file /sys/devices/system/cpu/isolated
This can be used by system management tools like libvirt,
openstack, and others to ensure proper placement of tasks.
Suggested-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Rik van Riel <riel@redhat.com>
Acked-by: Mike Galbraith <umgwanakikbuti@gmail.com>
Acked-by: Chris Metcalf <cmetcalf@ezchip.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Turns out we can automate the handling for the device_may_wakeup()
quite a bit by using the kernel wakeup source list as suggested
by Rafael J. Wysocki <rjw@rjwysocki.net>.
And as some hardware has separate dedicated wake-up interrupt
in addition to the IO interrupt, we can automate the handling by
adding a generic threaded interrupt handler that just calls the
device PM runtime to wake up the device.
This allows dropping code from device drivers as we currently
are doing it in multiple ways, and often wrong.
For most drivers, we should be able to drop the following
boilerplate code from runtime_suspend and runtime_resume
functions:
...
device_init_wakeup(dev, true);
...
if (device_may_wakeup(dev))
enable_irq_wake(irq);
...
if (device_may_wakeup(dev))
disable_irq_wake(irq);
...
device_init_wakeup(dev, false);
...
We can replace it with just the following init and exit
time code:
...
device_init_wakeup(dev, true);
dev_pm_set_wake_irq(dev, irq);
...
dev_pm_clear_wake_irq(dev);
device_init_wakeup(dev, false);
...
And for hardware with dedicated wake-up interrupts:
...
device_init_wakeup(dev, true);
dev_pm_set_dedicated_wake_irq(dev, irq);
...
dev_pm_clear_wake_irq(dev);
device_init_wakeup(dev, false);
...
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
If we don't update last_busy in rpm_resume, devices can go back
to sleep immediately after resume. This happens at least in
cases where the device has been powered off and does not have
any interrupt pending until there's something in the FIFO.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In the final iteration of commit 245bd6f6af ("PM / clock_ops: Add
pm_clk_add_clk()"), a refcount increment was added by Grygorii Strashko.
However, the accompanying IS_ERR() check operates on the wrong clock
pointer, which is always zero at this point, i.e. not an error.
This may lead to a NULL pointer dereference later, when __clk_get()
tries to dereference an error pointer.
Check the passed clock pointer instead to fix this.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Fixes: 245bd6f6af ("PM / clock_ops: Add pm_clk_add_clk()")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
After a wakeup_source is destroyed, we lost all information such as how
long this wakeup_source has been active. Add a dummy wakeup_source to
record such info.
Signed-off-by: Jin Qian <jinqian@android.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Most users of PM clocks do the extact same things in the runtime
suspend/resume callbacks. Provide them USE_PM_CLK_RUNTIME_OPS so
as to avoid/remove boilerplate code.
Signed-off-by: Rajendra Nayak <rnayak@codeaurora.org>
Reviewed-by: Kevin Hilman <khilman@linaro.org>
Acked-by: Santosh Shilimkar <ssantosh@kernel.org>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
A rogue wakeup source not registered in wakeup_sources list is not visible
from wakeup_sources_stats_show. Check if the wakeup source is registered
properly by looking at the timer struct.
Signed-off-by: Jin Qian <jinqian@android.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Existing regmap users call regcache_mark_dirty() as part of the
suspend/resume sequence, to tell regcache that non-default values need to
be resynced post-resume. Add an internal "no_sync_defaults" regmap flag
to remember this state, so that regcache_sync() can differentiate between
these two cases:
1) HW was reset, so any cache values that match map->reg_defaults can be
safely skipped. On some chips there are a lot of registers in the
reg_defaults list, so this optimization speeds things up quite a bit.
2) HW was not reset (maybe it was just clock-gated), so if we cached
any writes, they should be sent to the hardware regardless of whether
they match the HW default. Currently this will write out all values in
the regcache, since we don't maintain per-register dirty bits.
Suggested-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Kevin Cernekee <cernekee@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
We're going to add another "does this register need syncing?" check, so
rather than repeating it in three places, we'll separate all of the
relevant logic into a helper function.
Signed-off-by: Kevin Cernekee <cernekee@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
The irq_domain_ops are not modified by the driver and the irqdomain core
code accepts pointer to a const data.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Pull fourth vfs update from Al Viro:
"d_inode() annotations from David Howells (sat in for-next since before
the beginning of merge window) + four assorted fixes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
RCU pathwalk breakage when running into a symlink overmounting something
fix I_DIO_WAKEUP definition
direct-io: only inc/dec inode->i_dio_count for file systems
fs/9p: fix readdir()
VFS: assorted d_backing_inode() annotations
VFS: fs/inode.c helpers: d_inode() annotations
VFS: fs/cachefiles: d_backing_inode() annotations
VFS: fs library helpers: d_inode() annotations
VFS: assorted weird filesystems: d_inode() annotations
VFS: normal filesystems (and lustre): d_inode() annotations
VFS: security/: d_inode() annotations
VFS: security/: d_backing_inode() annotations
VFS: net/: d_inode() annotations
VFS: net/unix: d_backing_inode() annotations
VFS: kernel/: d_inode() annotations
VFS: audit: d_backing_inode() annotations
VFS: Fix up some ->d_inode accesses in the chelsio driver
VFS: Cachefiles should perform fs modifications on the top layer only
VFS: AF_UNIX sockets should call mknod on the top layer only
