Given a CPU running a loop containing cond_resched(), with no
other tasks runnable on that CPU, RCU will eventually report RCU
CPU stall warnings due to lack of quiescent states. Fortunately,
every call to cond_resched() is a perfectly good quiescent state.
Unfortunately, invoking rcu_note_context_switch() is a bit heavyweight
for cond_resched(), especially given the need to disable preemption,
and, for RCU-preempt, interrupts as well.
This commit therefore maintains a per-CPU counter that causes
cond_resched(), cond_resched_lock(), and cond_resched_softirq() to call
rcu_note_context_switch(), but only about once per 256 invocations.
This ratio was chosen in keeping with the relative time constants of
RCU grace periods.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
The definition for raw_cpu_add_return() uses the operation prefix
"raw_add_return_", but the definitions in the various percpu.h files
expect "raw_cpu_add_return_". This commit therefore appropriately
adjusts the definition of raw_cpu_add_return().
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Christoph Lameter <cl@linux.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
This commit allows rcutorture to print additional state for the
RCU grace-period kthreads in cases where RCU seems reluctant to
start a new grace period.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
As the decision to what needs to be done (converting a call to the
ftrace_caller to ftrace_caller_regs or to convert from ftrace_caller_regs
to ftrace_caller) can easily be determined from the rec->flags of
FTRACE_FL_REGS and FTRACE_FL_REGS_EN, there's no need to have the
ftrace_check_record() return either a UPDATE_MODIFY_CALL_REGS or a
UPDATE_MODIFY_CALL. Just he latter is enough. This added flag causes
more complexity than is required. Remove it.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Move and rename get_ftrace_addr() and get_ftrace_addr_old() to
ftrace_get_addr_new() and ftrace_get_addr_curr() respectively.
This moves these two helper functions in the generic code out from
the arch specific code, and renames them to have a better generic
name. This will allow other archs to use them as well as makes it
a bit easier to work on getting separate trampolines for different
functions.
ftrace_get_addr_new() returns the trampoline address that the mcount
call address will be converted to.
ftrace_get_addr_curr() returns the trampoline address of what the
mcount call address currently jumps to.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Add handling of OS Extended Properties descriptors from configfs interface.
One kind of "OS Descriptors" are "Extended Properties" descriptors, which
need to be specified per interface or per group of interfaces described
by an IAD. This patch adds support for creating subdirectories
in interface.<n> directory located in the function's directory.
Names of subdirectories created become names of properties.
Each property contains two attributes: "type" and "data".
The type can be a numeric value 1..7 while data is a blob interpreted
depending on the type specified.
The types are:
1 - unicode string
2 - unicode string with environment variables
3 - binary
4 - little-endian 32-bit
5 - big-endian 32-bit
6 - unicode string with a symbolic link
7 - multiple unicode strings
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Add handling of OS Extended Compatibility descriptors from configfs interface.
Hosts which expect the "OS Descriptors" ask only for configurations @ index 0,
but linux-based USB devices can provide more than one configuration.
This patch adds marking one of gadget's configurations the configuration
to be reported at index 0, regardless of the actual sequence of usb_add_config
invocations used for adding the configurations. The configuration is selected
by creating a symbolic link pointing to it from the "os_desc" directory
located at the top of a gadget's directory hierarchy.
One kind of "OS Descriptors" are "Extended Compatibility Descriptors",
which need to be specified per interface. This patch adds interface.<n>
directory in function's configfs directory to represent each interface
defined by the function. Each interface's directory contains two attributes:
"compatible_id" and "sub_compatible_id", which represent 8-byte
strings to be reported to the host as the "Compatible ID" and "Sub Compatible
ID".
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
There is a custom (non-USB IF) extension to the USB standard:
http://msdn.microsoft.com/library/windows/hardware/gg463182
They grant permission to use the specification - there is
"Microsoft OS Descriptor Specification License Agreement"
under the link mentioned above, and its Section 2 "Grant
of License", letter (b) reads:
"Patent license. Microsoft hereby grants to You a nonexclusive,
royalty-free, nontransferable, worldwide license under Microsoft’s
patents embodied solely within the Specification and that are owned
or licensable by Microsoft to make, use, import, offer to sell,
sell and distribute directly or indirectly to Your Licensees Your
Implementation. You may sublicense this patent license to Your
Licensees under the same terms and conditions."
The said extension is maintained by Microsoft for Microsoft.
Yet it is fairly common for various devices to use it, and a
popular proprietary operating system expects devices to provide
"OS descriptors", so Linux-based USB gadgets whishing to be able
to talk to a variety of operating systems should be able to provide
the "OS descriptors".
This patch adds optional support for gadgets whishing to expose
the so called "OS Feature Descriptors", that is "Extended Compatibility ID"
and "Extended Properties".
Hosts which do request "OS descriptors" from gadgets do so during
the enumeration phase and before the configuration is set with
SET_CONFIGURATION. What is more, those hosts never ask for configurations
at indices other than 0. Therefore, gadgets whishing to provide
"OS descriptors" must designate one configuration to be used with
this kind of hosts - this is what os_desc_config is added for in
struct usb_composite_dev. There is an additional advantage to it:
if a gadget provides "OS descriptors" and designates one configuration
to be used with such non-USB-compliant hosts it can invoke
"usb_add_config" in any order because the designated configuration
will be reported to be at index 0 anyway.
This patch also adds handling vendor-specific requests addressed
at device or interface and related to handling "OS descriptors".
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
There is a custom (non-USB IF) extension to the USB standard:
http://msdn.microsoft.com/library/windows/hardware/gg463182
They grant permission to use the specification - there is
"Microsoft OS Descriptor Specification License Agreement"
under the link mentioned above, and its Section 2 "Grant
of License", letter (b) reads:
"Patent license. Microsoft hereby grants to You a nonexclusive,
royalty-free, nontransferable, worldwide license under Microsoft’s
patents embodied solely within the Specification and that are owned
or licensable by Microsoft to make, use, import, offer to sell,
sell and distribute directly or indirectly to Your Licensees Your
Implementation. You may sublicense this patent license to Your
Licensees under the same terms and conditions."
The said extension is maintained by Microsoft for Microsoft.
Yet it is fairly common for various devices to use it, and a
popular proprietary operating system expects devices to provide
"OS descriptors", so Linux-based USB gadgets whishing to be able
to talk to a variety of operating systems should be able to provide
the "OS descriptors".
This patch adds optional support for gadgets whishing to expose
the so called "OS String" under index 0xEE of language 0.
The contents of the string is generated based on the qw_sign
array and b_vendor_code.
Interested gadgets need to set the cdev->use_os_string flag,
fill cdev->qw_sign with appropriate values and fill cdev->b_vendor_code
with a value of their choice.
This patch does not however implement responding to any vendor-specific
USB requests.
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Currently cgroup implements refcnting separately using atomic_t
cgroup->refcnt. The destruction paths of cgroup and css are rather
complex and bear a lot of similiarities including the use of RCU and
bouncing to a work item.
This patch makes cgroup use the refcnt of self css for refcnting
instead of using its own. This makes cgroup refcnting use css's
percpu refcnt and share the destruction mechanism.
* css_release_work_fn() and css_free_work_fn() are updated to handle
both csses and cgroups. This is a bit messy but should do until we
can make cgroup->self a full css, which currently can't be done
thanks to multiple hierarchies.
* cgroup_destroy_locked() now performs
percpu_ref_kill(&cgrp->self.refcnt) instead of cgroup_put(cgrp).
* Negative refcnt sanity check in cgroup_get() is no longer necessary
as percpu_ref already handles it.
* Similarly, as a cgroup which hasn't been killed will never be
released regardless of its refcnt value and percpu_ref has sanity
check on kill, cgroup_is_dead() sanity check in cgroup_put() is no
longer necessary.
* As whether a refcnt reached zero or not can only be decided after
the reference count is killed, cgroup_root->cgrp's refcnting can no
longer be used to decide whether to kill the root or not. Let's
make cgroup_kill_sb() explicitly initiate destruction if the root
doesn't have any children. This makes sense anyway as unmounted
cgroup hierarchy without any children should be destroyed.
While this is a bit messy, this will allow pushing more bookkeeping
towards cgroup->self and thus handling cgroups and csses in more
uniform way. In the very long term, it should be possible to
introduce a base subsystem and convert the self css to a proper one
making things whole lot simpler and unified.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Currently, css_get(), css_tryget() and css_tryget_online() are noops
for root csses as an optimization; however, we're planning to use css
refcnts to track of cgroup lifetime too and root cgroups also need to
be reference counted. Since css has been converted to percpu_refcnt,
the overhead of refcnting is miniscule and this optimization isn't too
meaningful anymore. Furthermore, controllers which optimize the root
cgroup often never even invoke these functions in their hot paths.
This patch enables refcnting for root csses too. This makes CSS_ROOT
flag unused and removes it.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
cgroup_destroy_css_killed() is cgroup destruction stage which happens
after all csses are offlined. After the recent updates, it no longer
does anything other than putting the base reference. This patch
removes the function and makes cgroup_destroy_locked() put the base
ref at the end isntead.
This also makes cgroup->nr_css unnecessary. Removed.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
cgroup->dummy_css is used as the placeholder css when performing css
oriended operations on the cgroup. We're gonna shift more cgroup
management to this css. Let's rename it to ->self and move it to the
top.
This is pure rename and field relocation.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
If the probed insn triggers a trap, ->si_addr = regs->ip is technically
correct, but this is not what the signal handler wants; we need to pass
the address of the probed insn, not the address of xol slot.
Add the new arch-agnostic helper, uprobe_get_trap_addr(), and change
fill_trap_info() and math_error() to use it. !CONFIG_UPROBES case in
uprobes.h uses a macro to avoid include hell and ensure that it can be
compiled even if an architecture doesn't define instruction_pointer().
Test-case:
#include <signal.h>
#include <stdio.h>
#include <unistd.h>
extern void probe_div(void);
void sigh(int sig, siginfo_t *info, void *c)
{
int passed = (info->si_addr == probe_div);
printf(passed ? "PASS\n" : "FAIL\n");
_exit(!passed);
}
int main(void)
{
struct sigaction sa = {
.sa_sigaction = sigh,
.sa_flags = SA_SIGINFO,
};
sigaction(SIGFPE, &sa, NULL);
asm (
"xor %ecx,%ecx\n"
".globl probe_div; probe_div:\n"
"idiv %ecx\n"
);
return 0;
}
it fails if probe_div() is probed.
Note: show_unhandled_signals users should probably use this helper too,
but we need to cleanup them first.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
net_get_random_once depends on the static keys infrastructure to patch up
the branch to the slow path during boot. This was realized by abusing the
static keys api and defining a new initializer to not enable the call
site while still indicating that the branch point should get patched
up. This was needed to have the fast path considered likely by gcc.
The static key initialization during boot up normally walks through all
the registered keys and either patches in ideal nops or enables the jump
site but omitted that step on x86 if ideal nops where already placed at
static_key branch points. Thus net_get_random_once branches not always
became active.
This patch switches net_get_random_once to the ordinary static_key
api and thus places the kernel fast path in the - by gcc considered -
unlikely path. Microbenchmarks on Intel and AMD x86-64 showed that
the unlikely path actually beats the likely path in terms of cycle cost
and that different nop patterns did not make much difference, thus this
switch should not be noticeable.
Fixes: a48e42920f ("net: introduce new macro net_get_random_once")
Reported-by: Tuomas Räsänen <tuomasjjrasanen@tjjr.fi>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Current hwrng core supports to register multiple hwrng devices,
and there is only one device really works in the same time.
QEMU alsu supports to have multiple virtio-rng backends.
This patch changes virtio-rng driver to support multiple
virtio-rng devices.
]# cat /sys/class/misc/hw_random/rng_available
virtio_rng.0 virtio_rng.1
]# cat /sys/class/misc/hw_random/rng_current
virtio_rng.0
]# echo -n virtio_rng.1 > /sys/class/misc/hw_random/rng_current
]# dd if=/dev/hwrng of=/dev/null
Signed-off-by: Amos Kong <akong@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Silence the warning when building with -Wsign-compare when cpumask.h
is included:
include/linux/cpumask.h: In function ‘cpumask_parse’:
include/linux/cpumask.h:603:26: warning: signed and unsigned type in conditional expression [-Wsign-compare]
int len = nl ? nl - buf : strlen(buf);
^
V2: Rusty pointed out that unsigned should be used instead.
Signed-off-by: Brian W Hart <hartb@linux.vnet.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Consolidate various cookie checking and generation code to simplify
the fast open processing. The main goal is to reduce code duplication
in tcp_v4_conn_request() for IPv6 support.
Removes two experimental sysctl flags TFO_SERVER_ALWAYS and
TFO_SERVER_COOKIE_NOT_CHKD used primarily for developmental debugging
purposes.
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Daniel Lee <longinus00@gmail.com>
Signed-off-by: Jerry Chu <hkchu@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The NCM class match in the cdc_mbim driver is confusing and
cause unexpected behaviour. The USB core guarantees that a
USB interface is in altsetting 0 when probing starts. This
means that devices implementing a NCM 1.0 backwards
compatible MBIM function (a "NCM/MBIM function") always hit
the NCM entry in the cdc_mbim driver match table. Such
functions will never match any of the MBIM entries.
This causes unexpeced behaviour for cases where the NCM and
MBIM entries are differet, which is currently the case for
all except Ericsson devices.
Improve the probing of NCM/MBIM functions by looking up the
device again in the cdc_mbim match table after switching to
the MBIM identity.
The shared altsetting selection is updated to better
accommodate the new probing logic, returning the preferred
altsetting for the control interface instead of the data
interface. The control interface altsetting update is moved
to the cdc_mbim driver. It is never necessary to change the
control interface altsetting for NCM.
Cc: Greg Suarez <gsuarez@smithmicro.com>
Reported by: Yu-an Shih <yshih@nvidia.com>
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: get rid of SET_ETHTOOL_OPS
Dave Miller mentioned he'd like to see SET_ETHTOOL_OPS gone.
This does that.
Mostly done via coccinelle script:
@@
struct ethtool_ops *ops;
struct net_device *dev;
@@
- SET_ETHTOOL_OPS(dev, ops);
+ dev->ethtool_ops = ops;
Compile tested only, but I'd seriously wonder if this broke anything.
Suggested-by: Dave Miller <davem@davemloft.net>
Signed-off-by: Wilfried Klaebe <w-lkml@lebenslange-mailadresse.de>
Acked-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This adds support for active queue tracking, meaning that the
blk-mq tagging maintains a count of active users of a tag set.
This allows us to maintain a notion of fairness between users,
so that we can distribute the tag depth evenly without starving
some users while allowing others to try unfair deep queues.
If sharing of a tag set is detected, each hardware queue will
track the depth of its own queue. And if this exceeds the total
depth divided by the number of active queues, the user is actively
throttled down.
The active queue count is done lazily to avoid bouncing that data
between submitter and completer. Each hardware queue gets marked
active when it allocates its first tag, and gets marked inactive
when 1) the last tag is cleared, and 2) the queue timeout grace
period has passed.
Signed-off-by: Jens Axboe <axboe@fb.com>
of_can_translate_address only checks some conditions for address
translation, but does not check other conditions like having range
properties. The checks it does do are redundant with
__of_address_translate. The only difference is printing a message or
not. Since we only have a single caller that does the full translation
anyway, just remove of_can_translate_address and quiet the error
message.
Cc: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Tested-by: Frank Rowand <frank.rowand@sonymobile.com>
Reviewed-by: Frank Rowand <frank.rowand@sonymobile.com>
The rcutorture output currently does not distinguish between stalls in
the RCU implementation and stalls in the rcu_torture_writer() kthreads.
This commit therefore adds some diagnostics to help distinguish between
these two conditions, at least for the non-SRCU implementations. (SRCU
does not provide evidence of update-side forward progress by design.)
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Now that cgroup_subtree_control_write() has access to the associated
kernfs_open_file and thus the kernfs_node, there's no need to cache it
in cgroup->control_kn on creation. Remove cgroup->control_kn and use
@of->kn directly.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
cftype->trigger() is pointless. It's trivial to ignore the input
buffer from a regular ->write() operation. Convert all ->trigger()
users to ->write() and remove ->trigger().
This patch doesn't introduce any visible behavior changes.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Convert all cftype->write_string() users to the new cftype->write()
which maps directly to kernfs write operation and has full access to
kernfs and cgroup contexts. The conversions are mostly mechanical.
* @css and @cft are accessed using of_css() and of_cft() accessors
respectively instead of being specified as arguments.
* Should return @nbytes on success instead of 0.
* @buf is not trimmed automatically. Trim if necessary. Note that
blkcg and netprio don't need this as the parsers already handle
whitespaces.
cftype->write_string() has no user left after the conversions and
removed.
While at it, remove unnecessary local variable @p in
cgroup_subtree_control_write() and stale comment about
CGROUP_LOCAL_BUFFER_SIZE in cgroup_freezer.c.
This patch doesn't introduce any visible behavior changes.
v2: netprio was missing from conversion. Converted.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Aristeu Rozanski <arozansk@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Acked-by: Li Zefan <lizefan@huawei.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: "David S. Miller" <davem@davemloft.net>
During the recent conversion to kernfs, cftype's seq_file operations
are updated so that they are directly mapped to kernfs operations and
thus can fully access the associated kernfs and cgroup contexts;
however, write path hasn't seen similar updates and none of the
existing write operations has access to, for example, the associated
kernfs_open_file.
Let's introduce a new operation cftype->write() which maps directly to
the kernfs write operation and has access to all the arguments and
contexts. This will replace ->write_string() and ->trigger() and ease
manipulation of kernfs active protection from cgroup file operations.
Two accessors - of_cft() and of_css() - are introduced to enable
accessing the associated cgroup context from cftype->write() which
only takes kernfs_open_file for the context information. The
accessors for seq_file operations - seq_cft() and seq_css() - are
rewritten to wrap the of_ accessors.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Unlike the more usual refcnting, what css_tryget() provides is the
distinction between online and offline csses instead of protection
against upping a refcnt which already reached zero. cgroup is
planning to provide actual tryget which fails if the refcnt already
reached zero. Let's rename the existing trygets so that they clearly
indicate that they're onliness.
I thought about keeping the existing names as-are and introducing new
names for the planned actual tryget; however, given that each
controller participates in the synchronization of the online state, it
seems worthwhile to make it explicit that these functions are about
on/offline state.
Rename css_tryget() to css_tryget_online() and css_tryget_from_dir()
to css_tryget_online_from_dir(). This is pure rename.
v2: cgroup_freezer grew new usages of css_tryget(). Update
accordingly.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Li Zefan <lizefan@huawei.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Pull to receive e37a06f109 ("cgroup: fix the retry path of
cgroup_mount()") to avoid unnecessary conflicts with planned
cgroup_tree_mutex removal and also to be able to remove the temp fix
added by 36c38fb714 ("blkcg: use trylock on blkcg_pol_mutex in
blkcg_reset_stats()") afterwards.
Signed-off-by: Tejun Heo <tj@kernel.org>
Determining the css of a task usually requires RCU read lock as that's
the only thing which keeps the returned css accessible till its
reference is acquired; however, testing whether a task belongs to the
root can be performed without dereferencing the returned css by
comparing the returned pointer against the root one in init_css_set[]
which never changes.
Implement task_css_is_root() which can be invoked in any context.
This will be used by the scheduled cgroup_freezer change.
v2: cgroup no longer supports modular controllers. No need to export
init_css_set. Pointed out by Li.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Add a new driver for the USB 3.0 PHY on Exynos5 series of SoCs.
The new driver uses the generic PHY framework and will interact
with DWC3 controller present on Exynos5 series of SoCs.
Also, created a new header file in linux/mfd/syscon/ for
Exynos5 SoCs and put the required PMU offset definitions
for the basic available PHYs.
Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
The kernfs open method - kernfs_fop_open() - inherited extra
permission checks from sysfs. While the vfs layer allows ignoring the
read/write permissions checks if the issuer has CAP_DAC_OVERRIDE,
sysfs explicitly denied open regardless of the cap if the file doesn't
have any of the UGO perms of the requested access or doesn't implement
the requested operation. It can be debated whether this was a good
idea or not but the behavior is too subtle and dangerous to change at
this point.
After cgroup got converted to kernfs, this extra perm check also got
applied to cgroup breaking libcgroup which opens write-only files with
O_RDWR as root. This patch gates the extra open permission check with
a new flag KERNFS_ROOT_EXTRA_OPEN_PERM_CHECK and enables it for sysfs.
For sysfs, nothing changes. For cgroup, root now can perform any
operation regardless of the permissions as it was before kernfs
conversion. Note that kernfs still fails unimplemented operations
with -EINVAL.
While at it, add comments explaining KERNFS_ROOT flags.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Andrey Wagin <avagin@gmail.com>
Tested-by: Andrey Wagin <avagin@gmail.com>
Cc: Li Zefan <lizefan@huawei.com>
References: http://lkml.kernel.org/g/CANaxB-xUm3rJ-Cbp72q-rQJO5mZe1qK6qXsQM=vh0U8upJ44+A@mail.gmail.com
Fixes: 2bd59d48eb ("cgroup: convert to kernfs")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The R8A7779 SoC has several clocks that are too custom to be supported in a
generic driver. Those clocks are all fixed rate clocks with multiplier and
divisor set according to boot mode configuration.
Based on work for R-Car Gen2 SoCs by Laurent Pinchart.
Cc: devicetree@vger.kernel.org
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
- Remove spaces in front of TABs,
- Correct indentation for some CLK_* flag descriptions.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
Callers of mmc_regulator_get_supply could benefit from knowing if either
of the regulators are present but not yet available. Since callers do
not currently examine the return value, modify this function to return
zero or -EPROBE_DEFER if either regulator get returns the same.
Furthermore, since callers check vmmc/vqmmc using IS_ERR and can deal
with absent regulators, switch to devm_regulator_get_optional. This has
the added benefit of allowing this function to behave correctly even in
the !CONFIG_REGULATOR case such that the stub can be removed.
Signed-off-by: Tim Kryger <tim.kryger@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <chris@printf.net>
This patch adds HS400 mode support for eMMC5.0 device. HS400 mode is high
speed DDR interface timing from HS200. Clock frequency is up to 200MHz
and only 8-bit bus width is supported. In addition, tuning process of
HS200 is required to synchronize the command response on the CMD line
because CMD input timing for HS400 mode is the same as HS200 mode.
Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
Reviewed-by: Jackey Shen <jackey.shen@amd.com>
Tested-by: Jaehoon Chung <jh80.chung@samsung.com>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <chris@printf.net>
Current implementation for bus speed mode selection is too
complicated. This patch is to simplify the codes and remove
some duplicate parts.
The following changes are including:
* Adds functions for each mode selection(HS, HS-DDR, HS200 and etc)
* Rearranged the mode selection sequence with supported device type
* Adds maximum speed for HS200 mode(hs200_max_dtr)
* Adds field definition for HS_TIMING of EXT_CSD
Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
Tested-by: Jaehoon Chung <jh80.chung@samsung.com>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <chris@printf.net>
Device types which are supported by both host and device can be
identified when EXT_CSD is read. There is no need to check host's
capability anymore.
Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
Tested-by: Jaehoon Chung <jh80.chung@samsung.com>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <chris@printf.net>
Timing mode identifier has same role and can take the place
of speed mode. This change removes all related speed mode.
Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
Tested-by: Jaehoon Chung <jh80.chung@samsung.com>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <chris@printf.net>
Since using the device-tree, didn't use the callback pointer.
So removed the unused callback pointer.
When the set_power callback is used, it should be added in future.
Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <chris@printf.net>
The __vlan_find_dev_deep should always called in RCU, according
David's suggestion, rename to __vlan_find_dev_deep_rcu looks more
reasonable.
Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As suggested by several people, rename local_df to ignore_df,
since it means "ignore df bit if it is set".
Cc: Maciej Żenczykowski <maze@google.com>
Cc: Florian Westphal <fw@strlen.de>
Cc: David S. Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/ethernet/altera/altera_sgdma.c
net/netlink/af_netlink.c
net/sched/cls_api.c
net/sched/sch_api.c
The netlink conflict dealt with moving to netlink_capable() and
netlink_ns_capable() in the 'net' tree vs. supporting 'tc' operations
in non-init namespaces. These were simple transformations from
netlink_capable to netlink_ns_capable.
The Altera driver conflict was simply code removal overlapping some
void pointer cast cleanups in net-next.
Signed-off-by: David S. Miller <davem@davemloft.net>
When we perform a data integrity sync we tag all the dirty pages with
PAGECACHE_TAG_TOWRITE at start of ext4_da_writepages. Later we check
for this tag in write_cache_pages_da and creates a struct
mpage_da_data containing contiguously indexed pages tagged with this
tag and sync these pages with a call to mpage_da_map_and_submit. This
process is done in while loop until all the PAGECACHE_TAG_TOWRITE
pages are synced. We also do journal start and stop in each iteration.
journal_stop could initiate journal commit which would call
ext4_writepage which in turn will call ext4_bio_write_page even for
delayed OR unwritten buffers. When ext4_bio_write_page is called for
such buffers, even though it does not sync them but it clears the
PAGECACHE_TAG_TOWRITE of the corresponding page and hence these pages
are also not synced by the currently running data integrity sync. We
will end up with dirty pages although sync is completed.
This could cause a potential data loss when the sync call is followed
by a truncate_pagecache call, which is exactly the case in
collapse_range. (It will cause generic/127 failure in xfstests)
To avoid this issue, we can use set_page_writeback_keepwrite instead of
set_page_writeback, which doesn't clear TOWRITE tag.
Cc: stable@vger.kernel.org
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Ashish Sangwan <a.sangwan@samsung.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Remove the option to provide the flags for mmc capabilities as platform
data, enforce it through DT.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Remove the option to provide signal direction configuration and
feeback clock as platform data, enforce it through DT.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
