The dentry hashing rules have been really quite complicated for a long
while, in odd ways. That made functions like __d_drop() very fragile
and non-obvious.
In particular, whether a dentry was hashed or not was indicated with an
explicit DCACHE_UNHASHED bit. That's despite the fact that the hash
abstraction that the dentries use actually have a 'is this entry hashed
or not' model (which is a simple test of the 'pprev' pointer).
The reason that was done is because we used the normal 'is this entry
unhashed' model to mark whether the dentry had _ever_ been hashed in the
dentry hash tables, and that logic goes back many years (commit
b3423415fb: "dcache: avoid RCU for never-hashed dentries").
That, in turn, meant that __d_drop had totally different unhashing logic
for the dentry hash table case and for the anonymous dcache case,
because in order to use the "is this dentry hashed" logic as a flag for
whether it had ever been on the RCU hash table, we had to unhash such a
dentry differently so that we'd never think that it wasn't 'unhashed'
and wouldn't be free'd correctly.
That's just insane. It made the logic really hard to follow, when there
were two different kinds of "unhashed" states, and one of them (the one
that used "list_bl_unhashed()") really had nothing at all to do with
being unhashed per se, but with a very subtle lifetime rule instead.
So turn all of it around, and make it logical.
Instead of having a DENTRY_UNHASHED bit in d_flags to indicate whether
the dentry is on the hash chains or not, use the hash chain unhashed
logic for that. Suddenly "d_unhashed()" just uses "list_bl_unhashed()",
and everything makes sense.
And for the lifetime rule, just use an explicit DENTRY_RCUACCEES bit.
If we ever insert the dentry into the dentry hash table so that it is
visible to RCU lookup, we mark it DENTRY_RCUACCESS to show that it now
needs the RCU lifetime rules. Now suddently that test at dentry free
time makes sense too.
And because unhashing now is sane and doesn't depend on where the dentry
got unhashed from (because the dentry hash chain details doesn't have
some subtle side effects), we can re-unify the __d_drop() logic and use
common code for the unhashing.
Also fix one more open-coded hash chain bit_spin_lock() that I missed in
the previous chain locking cleanup commit.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
These callbacks are only called in the syscore suspend/resume code on
interrupt chips which have been registered via the generic irq chip
mechanism. Calling those callbacks per irq would be rather icky, but
with the generic irq chip mechanism we can call this per registered
chip.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arm-kernel@lists.infradead.org
This adds support for disabling threading on a per-IRQ basis via the IRQ
status instead of the IRQ flow, which is necessary for interrupts that
don't follow the natural IRQ flow channels, such as those that are
virtually created.
The new APIs added are simply:
irq_set_thread()
irq_set_nothread()
which follow the rest of the IRQ status routines.
Chained handlers also have IRQ_NOTHREAD set on them automatically, making
the lack of threading explicit rather than implicit. Subsequently, the
nothread flag can be viewed through the standard genirq debugging
facilities.
[ tglx: Fixed cleanup fallout ]
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Link: http://lkml.kernel.org/r/%3C20110406210135.GF18426%40linux-sh.org%3E
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
it makes it simpler to keep track of the amount of
bytes received and simplifies how flush_to_ldisc counts
the remaining bytes. It also fixes a bug of lost bytes
on n_tty when flushing too many bytes via the USB
serial gadget driver.
Tested-by: Stefan Bigler <stefan.bigler@keymile.com>
Tested-by: Toby Gray <toby.gray@realvnc.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Before commit
b402843 (Driver core: move dev_get/set_drvdata to drivers/base/dd.c)
calling dev_set_drvdata with dev=NULL was an unchecked error. After some
discussion about what to return in this case removing the check (and so
producing a null pointer exception) seems fine.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When certain technologies shutdown their interface without waiting for
the acknowledgement from the chip. The receive_buf from the TTY would be
invoked a while after the relevant technology is unregistered.
This patch introduces a new flag "is_registered" which maintains the
state of protocols BT, FM or GPS and thereby removes the need to clear
the protocol data from ST when protocols gets unregistered.
This fixes corner cases when HCI RESET is sent down from bluetooth stack
and the receive_buf is called from tty after 250ms before which
bluetooth would have unregistered from the system.
OR - when FM application decides to close down the device without
sending a power-off FM command resulting in some RDS data or interrupt
data coming in after the driver is unregistered.
Signed-off-by: Pavan Savoy <pavan_savoy@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Right now all RCU walks fall back to reference walk when CONFIG_SECURITY
is enabled, even though just the standard capability module is active.
This is because security_inode_exec_permission unconditionally fails
RCU walks.
Move this decision to the low level security module. This requires
passing the RCU flags down the security hook. This way at least
the capability module and a few easy cases in selinux/smack work
with RCU walks with CONFIG_SECURITY=y
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Disk event code automatically blocks events on excl write. This is
primarily to avoid issuing polling commands while burning is in
progress. This behavior doesn't fit other types of devices with
removeable media where polling commands don't have adverse side
effects and door locking usually doesn't exist.
This patch introduces new genhd flag which controls the auto-blocking
behavior and uses it to enable auto-blocking only on optical devices.
Note for stable: 2.6.38 and later only
Cc: stable@kernel.org
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
block: Remove the extra check in queue_requests_store
block, blk-sysfs: Fix an err return path in blk_register_queue()
block: remove stale kerneldoc member from __blk_run_queue()
block: get rid of QUEUE_FLAG_REENTER
cfq-iosched: read_lock() does not always imply rcu_read_lock()
block: kill blk_flush_plug_list() export
The ISP1704/1707 chip can be put to full power down
state by asserting the CHIP_SEL line. This patch enables
platform or board specific hooks to put the device into
power down mode in case not needed.
This patch is a preparation for enabling this powering
routine in n900 (rx-51) devices.
Thanks to Heikki Krogerus for helping out with the patch.
Signed-off-by: Kalle Jokiniemi <kalle.jokiniemi@nokia.com>
Acked-By: Heikki Krogerus <heikki.krogerus@nokia.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
MAX8903 is an integrated battery charger and selector with two
power inputs (USB and AC adapter). This driver enables the charger,
handles interrupts, and provides power-supply-class information to
userland.
Tested on Exynos4 NURI / S5PC210 SLP7 boards.
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
We have platform code that needs to find a node's interrupt parent, so
export of_irq_find_parent() so we can use it.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The device_type structure does not contain data that changes
during usage and should be const. This allows devices to declare
the struct const.
I have patches to change all the subsystems, but need the infra
structure change first.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
it's quite useful to print the device name
on the stack dump caused by WARN(), but
there are other cases where we might want
to use WARN_ONCE.
Introduce a helper similar to dev_WARN() for
that case too.
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (51 commits)
netfilter: ipset: Fix the order of listing of sets
ip6_pol_route panic: Do not allow VLAN on loopback
bnx2x: Fix port identification problem
r8169: add Realtek as maintainer.
ip: ip_options_compile() resilient to NULL skb route
bna: fix memory leak during RX path cleanup
bna: fix for clean fw re-initialization
usbnet: Fix up 'FLAG_POINTTOPOINT' and 'FLAG_MULTI_PACKET' overlaps.
iwlegacy: fix tx_power initialization
Revert "tcp: disallow bind() to reuse addr/port"
qlcnic: limit skb frags for non tso packet
net: can: mscan: fix build breakage in mpc5xxx_can
netfilter: ipset: set match and SET target fixes
netfilter: ipset: bitmap:ip,mac type requires "src" for MAC
sctp: fix oops while removed transport still using as retran path
sctp: fix oops when updating retransmit path with DEBUG on
net: Disable NETIF_F_TSO_ECN when TSO is disabled
net: Disable all TSO features when SG is disabled
sfc: Use rmb() to ensure reads occur in order
ieee802154: Remove hacked CFLAGS in net/ieee802154/Makefile
...
Introduce deinitialize_tty_struct which should be called after
initialize_tty_struct and before successfull tty_ldisc_setup.
It calls tty_ldisc_deinit which is opposite of tty_ldisc_init. It only
puts a reference to ldisc and assigns NULL to tty->ldisc.
It will be used to shut down ldisc when tty_release cannot be called
yet.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Add a regulator consumer driver for rfkill to enable controlling radio
transmitters connected to voltage regulators using the regulator
framework.
A new "vrfkill" virtual supply is provided to use in platform code.
Signed-off-by: Guiming Zhuo <gmzhuo@gmail.com>
Signed-off-by: Antonio Ospite <ospite@studenti.unina.it>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
* 'timer-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
RTC: rtc-omap: Fix a leak of the IRQ during init failure
posix clocks: Replace mutex with reader/writer semaphore
Some platforms are incapable of triggering on level interrupts. Add a
platform quirks member in the platform data structure, as well as an
edge interrupt quirk which can be set on such platforms.
When the interrupt is requested with IRQF_TRIGGER_RISING, IRQF_ONESHOT
cannot be used, as we might miss interrupts that occur after the FW
status is cleared and before the threaded interrupt handler exits.
Moreover, when IRQF_ONESHOT is not set, iterating more than once in the
threaded interrupt handler introduces a few race conditions between this
handler and the hardirq handler. Currently this is worked around by
limiting the loop to one iteration only. This workaround has an impact
on performance. To remove to this restriction, the race conditions will
need to be addressed.
Signed-off-by: Ido Yariv <ido@wizery.com>
Signed-off-by: Luciano Coelho <coelho@ti.com>
Clean up the boot sequence code & fix the following issues:
1. Always read the registers' values and set the relevant bits instead of
zeroing all other bits
2. Handle cases where wl1271_top_reg_read returns an error
3. Verify that the HW can detect the selected clock source
4. Remove 128x PG10 initialization code
5. Configure the MCS PLL to work in HP mode
Signed-off-by: Ido Yariv <ido@wizery.com>
Reviewed-by: Luciano Coelho <coelho@ti.com>
Signed-off-by: Luciano Coelho <coelho@ti.com>
We are currently using this flag to check whether it's safe
to call into ->request_fn(). If it is set, we punt to kblockd.
But we get a lot of false positives and excessive punts to
kblockd, which hurts performance.
The only real abuser of this infrastructure is SCSI. So export
the async queue run and convert SCSI over to use that. There's
room for improvement in that SCSI need not always use the async
call, but this fixes our performance issue and they can fix that
up in due time.
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
If we fail to contact the gss upcall program, then no message will
be sent to the server. The client still updated the sequence number,
however, and this lead to NFS4ERR_SEQ_MISMATCH for the next several
RPC calls.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: xen-kbdfront - fix mouse getting stuck after save/restore
Input: estimate number of events per packet
Input: evdev - indicate buffer overrun with SYN_DROPPED
Input: document event types and codes and their intended use
Input: add KEY_IMAGES specifically for AL Image Browser
Input: twl4030_keypad - fix potential NULL dereference in twl4030_kp_probe()
Input: h3600_ts - fix error handling at connect
Input: twl4030_keypad - avoid potential NULL-pointer dereference
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
block: add blk_run_queue_async
block: blk_delay_queue() should use kblockd workqueue
md: fix up raid1/raid10 unplugging.
md: incorporate new plugging into raid5.
md: provide generic support for handling unplug callbacks.
md - remove old plugging code.
md/dm - remove remains of plug_fn callback.
md: use new plugging interface for RAID IO.
block: drop queue lock before calling __blk_run_queue() for kblockd punt
Revert "block: add callback function for unplug notification"
block: Enhance new plugging support to support general callbacks
next_pidmap() just quietly accepted whatever 'last' pid that was passed
in, which is not all that safe when one of the users is /proc.
Admittedly the proc code should do some sanity checking on the range
(and that will be the next commit), but that doesn't mean that the
helper functions should just do that pidmap pointer arithmetic without
checking the range of its arguments.
So clamp 'last' to PID_MAX_LIMIT. The fact that we then do "last+1"
doesn't really matter, the for-loop does check against the end of the
pidmap array properly (it's only the actual pointer arithmetic overflow
case we need to worry about, and going one bit beyond isn't going to
overflow).
[ Use PID_MAX_LIMIT rather than pid_max as per Eric Biederman ]
Reported-by: Tavis Ormandy <taviso@cmpxchg8b.com>
Analyzed-by: Robert Święcki <robert@swiecki.net>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Calculate a default based on the number of ABS axes, REL axes,
and MT slots for the device during input device registration.
Signed-off-by: Jeff Brown <jeffbrown@android.com>
Reviewed-by: Henrik Rydberg <rydberg@euromail.se>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Instead of overloading __blk_run_queue to force an offload to kblockd
add a new blk_run_queue_async helper to do it explicitly. I've kept
the blk_queue_stopped check for now, but I suspect it's not needed
as the check we do when the workqueue items runs should be enough.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
A dynamic posix clock is protected from asynchronous removal by a mutex.
However, using a mutex has the unwanted effect that a long running clock
operation in one process will unnecessarily block other processes.
For example, one process might call read() to get an external time stamp
coming in at one pulse per second. A second process calling clock_gettime
would have to wait for almost a whole second.
This patch fixes the issue by using a reader/writer semaphore instead of
a mutex.
Signed-off-by: Richard Cochran <richard.cochran@omicron.at>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/%3C20110330132421.GA31771%40riccoc20.at.omicron.at%3E
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Now that unplugging is done differently, the unplug_fn callback is
never called, so it can be completely discarded.
Signed-off-by: NeilBrown <neilb@suse.de>
MD can't use this since it really requires us to be able to
keep more than a single piece of state for the unplug. Commit
048c9374 added the required support for MD, so get rid of this
now unused code.
This reverts commit f75664570d.
Conflicts:
block/blk-core.c
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
md/raid requires an unplug callback, but as it does not uses
requests the current code cannot provide one.
So allow arbitrary callbacks to be attached to the blk_plug.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
block: make unplug timer trace event correspond to the schedule() unplug
block: let io_schedule() flush the plug inline
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
futex: Set FLAGS_HAS_TIMEOUT during futex_wait restart setup
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
perf_event: Fix cgrp event scheduling bug in perf_enable_on_exec()
perf: Fix a build error with some GCC versions
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
sched: Fix erroneous all_pinned logic
sched: Fix sched-domain avg_load calculation
* 'timer-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
RTC: rtc-mrst: follow on to the change of rtc_device_register()
RTC: add missing "return 0" in new alarm func for rtc-bfin.c
RTC: Fix s3c compile error due to missing s3c_rtc_setpie
RTC: Fix early irqs caused by calling rtc_set_alarm too early
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, amd: Disable GartTlbWlkErr when BIOS forgets it
x86, NUMA: Fix fakenuma boot failure
x86/mrst: Fix boot crash caused by incorrect pin to irq mapping
x86/ce4100: Add reg property to bridges
Linus correctly observes that the most important dispatch cases
are now done from kblockd, this isn't ideal for latency reasons.
The original reason for switching dispatches out-of-line was to
avoid too deep a stack, so by _only_ letting the "accidental"
flush directly in schedule() be guarded by offload to kblockd,
we should be able to get the best of both worlds.
So add a blk_schedule_flush_plug() that offloads to kblockd,
and only use that from the schedule() path.
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
block: only force kblockd unplugging from the schedule() path
block: cleanup the block plug helper functions
block, blk-sysfs: Use the variable directly instead of a function call
block: move queue run on unplug to kblockd
block: kill queue_sync_plugs()
block: readd plug trace event
block: add callback function for unplug notification
block: add comment on why we save and disable interrupts in flush_plug_list()
block: fixup block IO unplug trace call
block: remove block_unplug_timer() trace point
block: splice plug list to local context
