This prepares soc-camera to use struct v4l2_subdev_platform_data for its
subdevice-facing API, which would allow subdevice driver re-use.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
This struct shall be used by subdevice drivers to pass per-subdevice data,
e.g. power supplies, to generic V4L2 methods, at the same time allowing
optional host-specific extensions via the host_priv pointer. To avoid
having to pass two pointers to those methods, add a pointer to this new
struct to struct v4l2_subdev.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
BUG*() and WARN*() macros specify their conditions as unlikely, using
BUG_ON(unlikely(condition)) is redundant, remove it.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
In some environments it is to prefer to postpone the resume of the card
device until runtime_resume is being carried out, since it will mean a
signficant decrease of the total system resume time.
The reason of the decreased resume time is simply because of the actual
re-initalization of the card, which typically takes hundreds of
milliseconds, is performed outside the resume sequence and wont thus
affect it.
For removable card, the detect work tries to re-detect the card to make
sure it is still present, as a part of that sequence the card will also
be runtime_resumed and thus also fully resumed.
For a non-removable card, typically a mmc blk request will trigger a
runtime_resume and thus fully resume the card. This also means the
first request will likely suffer from an inital latency since the
re-initialization of the card needs to be performed.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
By adding a card state that records if it is suspended or resumed, we
can accept asyncronus suspend/resume requests for the mmc and sd
bus_ops.
MMC_CAP_AGGRESSIVE_PM, will at request inactivity through the runtime
bus_ops callbacks, execute a suspend of the the card. In the state were
this has been done, we can receive a suspend request for the mmc bus,
which for sd and mmc forced the card to active state by a
pm_runtime_get_sync. In other words, the card was resumed and then
immediately suspended again, completely unnecessary.
Since the suspend/resume bus_ops callbacks for sd and mmc are now
capable of handling asynchronous requests, we no longer need to force
the card to active state before executing suspend. Evidently preventing
the above sequence for MMC_CAP_AGGRESSIVE_PM.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
The are no more users of the deprecated mmc_suspend|resume_host API,
so let's remove it.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
The negotiated ocr mask is directly related to the card. Once a card
gets removed, the mask shall be dropped. By moving the cache of the ocr
mask from the host struct to the card struct we have accomplished this.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
Some switch operations like poweroff notify, shall according to the
spec not be followed by any other new commands. For these cases and
when the host does'nt support MMC_CAP_WAIT_WHILE_BUSY, we must not
send status commands to poll for busy detection. Instead wait for
the stated timeout from the EXT_CSD before completing the request.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
There are few special cases like exynos5440 which doesn't send POSTCHANGE
notification from their ->target() routine and call some kind of bottom halves
for doing this work, work/tasklet/etc.. From which they finally send POSTCHANGE
notification.
Its better if we distinguish them from other cpufreq drivers in some way so that
core can handle them specially. So this patch introduces another flag:
CPUFREQ_ASYNC_NOTIFICATION, which will be set by such drivers.
This also changes exynos5440-cpufreq.c and powernow-k8 in order to set this
flag.
Acked-by: Amit Daniel Kachhap <amit.daniel@samsung.com>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The server does allow NFS over v4.2, even if it doesn't add any new
operations yet.
I also switch to using constants to represent the last operation for
each minor version since this makes the code cleaner and easier to
understand at a quick glance.
Signed-off-by: Anna Schumaker <bjschuma@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Conflicts:
arch/arm/kernel/head.S
This series has been well tested and it would be great to get this
merged now.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
this_cpu_sub() is implemented as negation and addition.
This patch casts the adjustment to the counter type before negation to
sign extend the adjustment. This helps in cases where the counter type
is wider than an unsigned adjustment. An alternative to this patch is
to declare such operations unsupported, but it seemed useful to avoid
surprises.
This patch specifically helps the following example:
unsigned int delta = 1
preempt_disable()
this_cpu_write(long_counter, 0)
this_cpu_sub(long_counter, delta)
preempt_enable()
Before this change long_counter on a 64 bit machine ends with value
0xffffffff, rather than 0xffffffffffffffff. This is because
this_cpu_sub(pcp, delta) boils down to this_cpu_add(pcp, -delta),
which is basically:
long_counter = 0 + 0xffffffff
Also apply the same cast to:
__this_cpu_sub()
__this_cpu_sub_return()
this_cpu_sub_return()
All percpu_test.ko passes, especially the following cases which
previously failed:
l -= ui_one;
__this_cpu_sub(long_counter, ui_one);
CHECK(l, long_counter, -1);
l -= ui_one;
this_cpu_sub(long_counter, ui_one);
CHECK(l, long_counter, -1);
CHECK(l, long_counter, 0xffffffffffffffff);
ul -= ui_one;
__this_cpu_sub(ulong_counter, ui_one);
CHECK(ul, ulong_counter, -1);
CHECK(ul, ulong_counter, 0xffffffffffffffff);
ul = this_cpu_sub_return(ulong_counter, ui_one);
CHECK(ul, ulong_counter, 2);
ul = __this_cpu_sub_return(ulong_counter, ui_one);
CHECK(ul, ulong_counter, 1);
Signed-off-by: Greg Thelen <gthelen@google.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We currently use some ad-hoc arch variables tied to legacy KVM device
assignment to manage emulation of instructions that depend on whether
non-coherent DMA is present. Create an interface for this, adapting
legacy KVM device assignment and adding VFIO via the KVM-VFIO device.
For now we assume that non-coherent DMA is possible any time we have a
VFIO group. Eventually an interface can be developed as part of the
VFIO external user interface to query the coherency of a group.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Default to operating in coherent mode. This simplifies the logic when
we switch to a model of registering and unregistering noncoherent I/O
with KVM.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
So far we've succeeded at making KVM and VFIO mostly unaware of each
other, but areas are cropping up where a connection beyond eventfds
and irqfds needs to be made. This patch introduces a KVM-VFIO device
that is meant to be a gateway for such interaction. The user creates
the device and can add and remove VFIO groups to it via file
descriptors. When a group is added, KVM verifies the group is valid
and gets a reference to it via the VFIO external user interface.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add a kvm ioctl which states which system functionality kvm emulates.
The format used is that of CPUID and we return the corresponding CPUID
bits set for which we do emulate functionality.
Make sure ->padding is being passed on clean from userspace so that we
can use it for something in the future, after the ioctl gets cast in
stone.
s/kvm_dev_ioctl_get_supported_cpuid/kvm_dev_ioctl_get_cpuid/ while at
it.
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
edma header defines DMA_COMPLETE, this causes issues as commit adfedd9a32 move
DMA_SUCCESS to DMA_COMPLETE. edma should properly namespace its defines and
needs a future fix
Reported-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The ACPI spec requires the reset register width to be 8, so we
now hardcode it and ignore the FADT value. This provides/maintains
compatibility with other ACPI implementations that have allowed
BIOS code with bad register width values to go unnoticed.
Matthew Garett, Bob Moore, Lv Zheng.
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In the common case, the ACPI_ALLOCATE and related macros now resolve
directly to their respective acpi_os* OSL interfaces. Two options:
1) The ACPI_ALLOCATE_ZEROED macro defaults to a simple local implementation
by default, unless overridden by the USE_NATIVE_ALLOCATE_ZEROED define.
2) For ACPI execution simulation environment (AcpiExec) which is not
shipped with the Linux kernel, the macros can optionally be resolved to
the local interfaces that track each allocation (used to immediately
detect memory leaks).
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This fix repairs a version of a macro that is used for the hardware
reduced case only. It adds a return statement to the macro definition
so that the translation into the Linux kernel source will not completely
delete the second line of the macro because it thinks that it is an empty
block. It actually clarifies the use of the macro anyway.
Reported-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Using a spinlock to atomically increase a counter sounds wrong -- we've
atomic_t for this!
Also move 'seq_nr' to a different cache line than 'lock' to reduce cache
line trashing. This has the nice side effect of decreasing the size of
struct parallel_data from 192 to 128 bytes for a x86-64 build, e.g.
occupying only two instead of three cache lines.
Those changes results in a 5% performance increase on an IPsec test run
using pcrypt.
Btw. the seq_lock spinlock was never explicitly initialized -- one more
reason to get rid of it.
Signed-off-by: Mathias Krause <mathias.krause@secunet.com>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Fixes this build error:
In file included from include/asm-generic/gpio.h:13:0,
from include/linux/gpio.h:51,
from include/linux/of_gpio.h:20,
from arch/powerpc/sysdev/ppc4xx_gpio.c:29:
include/linux/gpio/driver.h:85:14: error: 'struct seq_file' declared inside=
parameter list [-Werror]
include/linux/gpio/driver.h:85:14: error: its scope is only this definition=
or declaration, which is probably not what you want [-Werror]
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Fixes this build error on sparc:
In file included from drivers/spi/spi.c:33:0:
include/linux/of_gpio.h: In function 'of_get_named_gpio_flags':
include/linux/of_gpio.h:93:3: error: implicit declaration of function 'desc_to_gpio' [-Werror=implicit-function-declaration]
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
commit 6b3d8145dcfdbbb43f13544e16f44f4574f941dd
"gpiolib: make GPIO_DEVRES depend on GPIOLIB"
breaks builds when device drivers are using devm_gpio*
devres functions without enabling GPIOLIB, relying on
the devres code to be compiled anyway.
Provide stubs so that we get these if we're using the
devres functions without GPIOLIB.
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Cc: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
cpuidle_unregister_governor() and cpuidle_replace_governor() aren't
used anymore and can be removed. They were used by cpufreq governors
earlier, but since the governors can't be compiled as modules any
more, these two functions aren't necessary.
Suggested-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
pr_debug_ratelimited should be coded similarly to dev_dbg_ratelimited
to reduce the "callbacks suppressed" messages.
Add #include <linux/dynamic_debug.h> to printk.h. Unfortunately, this
new #include must be after the prototype/declaration of function printk.
It may be better to split out these _ratelimited declarations into
a separate file one day.
Any use of these pr_<foo>_ratelimited functions must also have another
specific #include <ratelimited.h>. Most users have this done indirectly
via #include <linux/kernel.h>
printk.h may not #include <linux/ratelimit.h> as it causes circular
dependencies and compilation failures.
Signed-off-by: Joe Perches <joe@perches.com>
Tested-by: Krzysztof Mazur <krzysiek@podlesie.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
dev_WARN() and dev_WARN_ONCE() are annoying because (1) they include
only the driver name, not the device name, and (2) they print a spurious
newline in the middle. This results in messages like this that are less
useful than they should be:
[ 40.094995] Device pcieport
disabling already-disabled device
This patch makes them work more like dev_printk().
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Function acpi_processor_load_module() used by the ACPI processor
driver can only really work if the acpi-cpufreq module is available
when acpi_processor_start() is executed which usually is not the case
for systems loading the processor driver module from an initramfs.
Moreover, that used to be a hackish workaround for module autoloading
issues, but udev loads acpi-cpufreq just fine nowadays, so that
function isn't really necessary any more. For this reason, drop
acpi_processor_load_module() entirely.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Jeff Kirsher says:
====================
This series contains updates to vxlan, net, ixgbe, ixgbevf, and i40e.
Joseph provides a single patch against vxlan which removes the burden
from the NIC drivers to check if the vxlan driver is enabled in the
kernel and also makes available the vxlan headrooms to the drivers.
Jacob provides majority of the patches, with patches against net, ixgbe
and ixgbevf. His net patch adds might_sleep() call to napi_disable so
that every use of napi_disable during atomic context will be visible.
Then Jacob provides a patch to fix qv_lock_napi call in
ixgbe_napi_disable_all. The other ixgbe patches cleanup
ixgbe_check_minimum_link function to correctly show that there are some
minor loss of encoding, even though we don't calculate it and remove
unnecessary duplication of PCIe bandwidth display. Lastly, Jacob
provides 4 patches against ixgbevf to add ixgbevf_rx_skb in line with
how ixgbe handles the variations on how packets can be received, adds
support in order to track how many packets were cleaned during busy poll
as part of the extended statistics.
Wei Yongjun provides a fix for i40e to return -ENOMEN in the memory
allocation error handling case instead of returning 0, as done
elsewhere in this function.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This work contains a lightweight BPF-based traffic classifier that can
serve as a flexible alternative to ematch-based tree classification, i.e.
now that BPF filter engine can also be JITed in the kernel. Naturally, tc
actions and policies are supported as well with cls_bpf. Multiple BPF
programs/filter can be attached for a class, or they can just as well be
written within a single BPF program, that's really up to the user how he
wishes to run/optimize the code, e.g. also for inversion of verdicts etc.
The notion of a BPF program's return/exit codes is being kept as follows:
0: No match
-1: Select classid given in "tc filter ..." command
else: flowid, overwrite the default one
As a minimal usage example with iproute2, we use a 3 band prio root qdisc
on a router with sfq each as leave, and assign ssh and icmp bpf-based
filters to band 1, http traffic to band 2 and the rest to band 3. For the
first two bands we load the bytecode from a file, in the 2nd we load it
inline as an example:
echo 1 > /proc/sys/net/core/bpf_jit_enable
tc qdisc del dev em1 root
tc qdisc add dev em1 root handle 1: prio bands 3 priomap 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
tc qdisc add dev em1 parent 1:1 sfq perturb 16
tc qdisc add dev em1 parent 1:2 sfq perturb 16
tc qdisc add dev em1 parent 1:3 sfq perturb 16
tc filter add dev em1 parent 1: bpf run bytecode-file /etc/tc/ssh.bpf flowid 1:1
tc filter add dev em1 parent 1: bpf run bytecode-file /etc/tc/icmp.bpf flowid 1:1
tc filter add dev em1 parent 1: bpf run bytecode-file /etc/tc/http.bpf flowid 1:2
tc filter add dev em1 parent 1: bpf run bytecode "`bpfc -f tc -i misc.ops`" flowid 1:3
BPF programs can be easily created and passed to tc, either as inline
'bytecode' or 'bytecode-file'. There are a couple of front-ends that can
compile opcodes, for example:
1) People familiar with tcpdump-like filters:
tcpdump -iem1 -ddd port 22 | tr '\n' ',' > /etc/tc/ssh.bpf
2) People that want to low-level program their filters or use BPF
extensions that lack support by libpcap's compiler:
bpfc -f tc -i ssh.ops > /etc/tc/ssh.bpf
ssh.ops example code:
ldh [12]
jne #0x800, drop
ldb [23]
jneq #6, drop
ldh [20]
jset #0x1fff, drop
ldxb 4 * ([14] & 0xf)
ldh [%x + 14]
jeq #0x16, pass
ldh [%x + 16]
jne #0x16, drop
pass: ret #-1
drop: ret #0
It was chosen to load bytecode into tc, since the reverse operation,
tc filter list dev em1, is then able to show the exact commands again.
Possible follow-up work could also include a small expression compiler
for iproute2. Tested with the help of bmon. This idea came up during
the Netfilter Workshop 2013 in Copenhagen. Also thanks to feedback from
Eric Dumazet!
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
uprobe_copy_process() does nothing if the child shares ->mm with
the forking process, but there is a special case: CLONE_VFORK.
In this case it would be more correct to do dup_utask() but avoid
dup_xol(). This is not that important, the child should not unwind
its stack too much, this can corrupt the parent's stack, but at
least we need this to allow to ret-probe __vfork() itself.
Note: in theory, it would be better to check task_pt_regs(p)->sp
instead of CLONE_VFORK, we need to dup_utask() if and only if the
child can return from the function called by the parent. But this
needs the arch-dependant helper, and I think that nobody actually
does clone(same_stack, CLONE_VM).
Reported-by: Martin Cermak <mcermak@redhat.com>
Reported-by: David Smith <dsmith@redhat.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
linux/uprobes.h declares arch_uprobe_skip_sstep() as a weak function.
But as there is no definition of generic version so when trying to build
uprobes for an architecture that doesn't yet have a arch_uprobe_skip_sstep()
implementation, the vmlinux will try to call arch_uprobe_skip_sstep()
somehwere in Stupidhistan leading to a system crash. We rather want a
proper link error so remove arch_uprobe_skip_sstep().
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
The size of the register cache array is actually 6 instead of 7,
as it caches up to AK4114_REG_INT1_MASK. This resulted in unexpected
access out of array range, although most of them aren't so serious
(just reading one more byte on the stack at snd_ak4114_create()).
Also, the check of cache size was wrongly done by checking with
sizeof() instead of ARRAY_SIZE(). Fixed this together.
(And yes, hardcoded numbers are bad, but I keep the coding style as is
for making it clear what this patch actually does.)
Spotted by coverity among several CIDs, e.g. 711621.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Add fb_<level> convenience macros for emitting the
"fb%d: ", struct fb_info->node value.
Neatens and shortens the code a bit.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
napi_disable uses an msleep() call to wait for outstanding napi work to be
finished after setting the disable bit. It does not always sleep incase there
was no outstanding work. This resulted in a rare bug in ixgbe_down operation
where a napi_disable call took place inside of a local_bh_disable()d context.
In order to enable easier detection of future sleep while atomic BUGs, this
patch adds a might_sleep() call, so that every use of napi_disable during
atomic context will be visible.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Cc: Eliezer Tamir <eliezer.tamir@linux.intel.com>
Cc: Alexander Duyck <alexander.duyck@intel.com>
Cc: Hyong-Youb Kim <hykim@myri.com>
Cc: Amir Vadai <amirv@mellanox.com>
Cc: Dmitry Kravkov <dmitry@broadcom.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This patch removes the burden from the NIC drivers to check if the
vxlan driver is enabled in the kernel and also makes available
the vxlan headrooms to them.
Signed-off-by: Joseph Gasparakis <joseph.gasparakis@intel.com>
Tested-by: Kavindya Deegala <kavindya.s.deegala@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Add new function virtqueue_is_broken(). Callers of virtqueue_get_buf()
should check for a broken queue.
Signed-off-by: Heinz Graalfs <graalfs@linux.vnet.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
virtqueue_{kick()/notify()} should exploit the new host notification API.
If the notify call returned with a negative value the host kick failed
(e.g. a kick triggered after a device was hot-unplugged). In this case
the virtqueue is set to 'broken' and false is returned, otherwise true.
Signed-off-by: Heinz Graalfs <graalfs@linux.vnet.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Currently a host kick error is silently ignored and not reflected in
the virtqueue of a particular virtio device.
Changing the notify API for guest->host notification seems to be one
prerequisite in order to be able to handle such errors in the context
where the kick is triggered.
This patch changes the notify API. The notify function must return a
bool return value. It returns false if the host notification failed.
Signed-off-by: Heinz Graalfs <graalfs@linux.vnet.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The code for privacy extentions is very mature, and making it
configurable only gives marginal memory/code savings in exchange
for obfuscation and hard to read code via CPP ifdef'ery.
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull fs-cache fixes from David Howells:
Can you pull these commits to fix an issue with NFS whereby caching can be
enabled on a file that is open for writing by subsequently opening it for
reading. This can be made to crash by opening it for writing again if you're
quick enough.
The gist of the patchset is that the cookie should be acquired at inode
creation only and subsequently enabled and disabled as appropriate (which
dispenses with the backing objects when they're not needed).
The extra synchronisation that NFS does can then be dispensed with as it is
thenceforth managed by FS-Cache.
Could you send these on to Linus?
This likely will need fixing also in CIFS and 9P also once the FS-Cache
changes are upstream. AFS and Ceph are probably safe.
* 'fscache' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
NFS: Use i_writecount to control whether to get an fscache cookie in nfs_open()
FS-Cache: Provide the ability to enable/disable cookies
FS-Cache: Add use/unuse/wake cookie wrappers
Make the ksymtab symbols for EXPORT_SYMBOL visible.
This prevents the LTO compiler from adding a .NUMBER prefix,
which avoids various problems in later export processing.
Cc: rusty@rustcorp.com.au
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
