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2009-04-01powerpc/83xx: add mmc-spi support via the device tree for MPC8323E-RDBAnton Vorontsov
- Add gpio-controller node to manage QE GPIO Bank D; - Add mmc-spi node; - Modify board file so that it won't use legacy SPI support with the new device trees. Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com> Cc: David Brownell <david-b@pacbell.net> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Kumar Gala <galak@gate.crashing.org> Cc: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01powerpc: add mmc-spi-slot bindingsAnton Vorontsov
The bindings describes a case where MMC/SD/SDIO slot directly connected to a SPI bus. Such setups are widely used on embedded PowerPC boards. The patch also adds the mmc-spi-slot entry to the OpenFirmware modalias table. Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com> Cc: David Brownell <david-b@pacbell.net> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Kumar Gala <galak@gate.crashing.org> Cc: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01spi_mpc83xx: add OF platform driver bindingsAnton Vorontsov
Implement full support for OF SPI bindings. Now the driver can manage its own chip selects without any help from the board files and/or fsl_soc constructors. The "legacy" code is well isolated and could be removed as time goes by. Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com> Cc: David Brownell <david-b@pacbell.net> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Kumar Gala <galak@gate.crashing.org> Cc: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01spi_mpc83xx: rework chip selects handlingAnton Vorontsov
The main purpose of this patch is to pass 'struct spi_device' to the chip select handling routines. This is needed so that we could implement full-fledged OpenFirmware support for this driver. While at it, also: - Replace two {de,activate}_cs routines by single cs_contol(). - Don't duplicate platform data callbacks in mpc83xx_spi struct. Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com> Cc: David Brownell <david-b@pacbell.net> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Kumar Gala <galak@gate.crashing.org> Cc: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01spi_mpc83xx: fix sparse warningsAnton Vorontsov
The patch fixes following sparse warnings: CHECK spi_mpc83xx.c spi_mpc83xx.c:145:1: warning: symbol 'mpc83xx_spi_rx_buf_u8' was not declared. Should it be static? spi_mpc83xx.c:146:1: warning: symbol 'mpc83xx_spi_rx_buf_u16' was not declared. Should it be static? spi_mpc83xx.c:147:1: warning: symbol 'mpc83xx_spi_rx_buf_u32' was not declared. Should it be static? spi_mpc83xx.c:148:1: warning: symbol 'mpc83xx_spi_tx_buf_u8' was not declared. Should it be static? spi_mpc83xx.c:149:1: warning: symbol 'mpc83xx_spi_tx_buf_u16' was not declared. Should it be static? spi_mpc83xx.c:150:1: warning: symbol 'mpc83xx_spi_tx_buf_u32' was not declared. Should it be static? spi_mpc83xx.c:175:32: warning: incorrect type in initializer (different address spaces) spi_mpc83xx.c:175:32: expected void *tmp_ptr spi_mpc83xx.c:175:32: got unsigned int [noderef] <asn:2>*<noident> spi_mpc83xx.c:183:26: warning: incorrect type in argument 1 (different address spaces) spi_mpc83xx.c:183:26: expected unsigned int [noderef] [usertype] <asn:2>*reg spi_mpc83xx.c:183:26: got void *tmp_ptr spi_mpc83xx.c:184:26: warning: incorrect type in argument 1 (different address spaces) spi_mpc83xx.c:184:26: expected unsigned int [noderef] [usertype] <asn:2>*reg spi_mpc83xx.c:184:26: got void *tmp_ptr spi_mpc83xx.c:287:31: warning: incorrect type in initializer (different address spaces) spi_mpc83xx.c:287:31: expected void *tmp_ptr spi_mpc83xx.c:287:31: got unsigned int [noderef] <asn:2>*<noident> spi_mpc83xx.c:295:25: warning: incorrect type in argument 1 (different address spaces) spi_mpc83xx.c:295:25: expected unsigned int [noderef] [usertype] <asn:2>*reg spi_mpc83xx.c:295:25: got void *tmp_ptr spi_mpc83xx.c:296:25: warning: incorrect type in argument 1 (different address spaces) spi_mpc83xx.c:296:25: expected unsigned int [noderef] [usertype] <asn:2>*reg spi_mpc83xx.c:296:25: got void *tmp_ptr spi_mpc83xx.c:486:13: warning: symbol 'mpc83xx_spi_irq' was not declared. Should it be static? Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com> Cc: David Brownell <david-b@pacbell.net> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Kumar Gala <galak@gate.crashing.org> Cc: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01ramfs: add support for "mode=" mount optionWu Fengguang
Addresses http://bugzilla.kernel.org/show_bug.cgi?id=12843 "I use ramfs instead of tmpfs for /tmp because I don't use swap on my laptop. Some apps need 1777 mode for /tmp directory, but ramfs does not support 'mode=' mount option." Reported-by: Avan Anishchuk <matimatik@gmail.com> Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01lis3: SPI transport layerDaniel Mack
Make use of the new abstraction layer and add a new transport layer for spi. Works fine on a PXA based board. Signed-off-by: Daniel Mack <daniel@caiaq.de> Acked-by: Pavel Machek <pavel@ucw.cz> Acked-by: Eric Piel <eric.piel@tremplin-utc.net> Cc: David Brownell <david-b@pacbell.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01lis3: solve dependency between core and ACPIDaniel Mack
This solves the dependency between lis3lv02d.[ch] and ACPI specific methods. It introduces a ->bus_priv pointer to the device struct which is casted to 'struct acpi_device' in the ACIP layer. Changed hp_accel.c accordingly. Signed-off-by: Daniel Mack <daniel@caiaq.de> Acked-by: Pavel Machek <pavel@ucw.cz> Acked-by: Eric Piel <eric.piel@tremplin-utc.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01lis3: reorder functions to make forward decl obsoleteDaniel Mack
Move lis3lv02d_init_device() down so that the forward declaration of lis3lv02d_add_fs() becomes unnecessary. Signed-off-by: Daniel Mack <daniel@caiaq.de> Acked-by: Pavel Machek <pavel@ucw.cz> Acked-by: Eric Piel <eric.piel@tremplin-utc.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01hp_accel: axis conversion for hp compaq 8710wLuca Cappa
I have a laptop HP Compaq 8710W, I compiled into my kernel the LIS3LV02DL and HP_ACCEL module drivers. While loading it cannot recognize the laptop model, so i am sending the necessary information to update the database of axis orientations. >When the laptop is horizontal the position reported is about 0 for X and Y >and a positive value for Z Yes, it is about 0,0,1000, the actual reading says: (-17,-26,1018); > If the left side is elevated, X increases (becomes positive) Yes, X goes toward to positive 1000. >If the front side (where the touchpad is) is elevated, Y decreases (becomes negative) No, Y goes toward to positive 1000. >If the laptop is put upside-down, Z becomes negative Yes, the laptop on a table Z gives 1000, and if upsidedown the Z reads -1000. So in few words the Y axis is inverted. Cc: Eric Piel <eric.piel@tremplin-utc.net> Signed-off-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01hp_accel: add two more axis informationPavel Machek
Add two more laptops to whitelist. Signed-off-by: Michal Marek <mmarek@suse.cz> Signed-off-by: Pavel Machek <pavel@ucw.cz> Cc: Daniel Mack <daniel@caiaq.de> Cc: Eric Piel <eric.piel@tremplin-utc.net> Cc: Vladimir Botka <vbotka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01hwmon: Add LTC4215 driverIra Snyder
Add Linux support for the Linear Technology LTC4215 Hot Swap controller I2C monitoring interface. I have tested the driver with my board, and it appears to work fine. With the power supplies disabled, it reads 11.93V input, 1.93V output, no current and no power. With the supplies enabled, it reads 11.93V input, 11.98V output, no current, no power. I'm not drawing any current at the moment, so this is reasonable. The value in the sense register never reads anything except 0, so I expect to get zero from the current and power calculations. I didn't attempt to support changing any of the chip's settings or enabling the FET. I'm not sure even how to do that and still fit within the hwmon framework. :) Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu> Cc: Jean Delvare <khali@linux-fr.org> Cc: "Mark M. Hoffman" <mhoffman@lightlink.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01hwmon: LM95241 driverDavide Rizzo
An hwmon driver for the National Semiconductor LM95241 triple temperature sensors chip Signed-off-by: Davide Rizzo <elpa-rizzo@gmail.com> Cc: Jean Delvare <khali@linux-fr.org> Cc: "Mark M. Hoffman" <mhoffman@lightlink.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01hp_accel: adev is poor name of exported symbolPavel Machek
As Andrew noted, adev is pretty poor name for symbol being exported. Rename it to lis3. Signed-off-by: Pavel Machek <pavel@ucw.cz> Cc: Eric Piel <eric.piel@tremplin-utc.net> Cc: Vladimir Botka <vbotka@suse.cz> Cc: <Quoc.Pham@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01hp_accel: small documentation updatesPavel Machek
Fix english in Documentation, add "how to test" description. Signed-off-by: Pavel Machek <pavel@suse.cz> Cc: Eric Piel <eric.piel@tremplin-utc.net> Cc: Vladimir Botka <vbotka@suse.cz> Cc: <Quoc.Pham@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01epoll keyed wakeups: make tty use keyed wakeupsDavide Libenzi
Introduce keyed event wakeups inside the TTY code. Signed-off-by: Davide Libenzi <davidel@xmailserver.org> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Miller <davem@davemloft.net> Cc: William Lee Irwin III <wli@movementarian.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01epoll keyed wakeups: make eventfd use keyed wakeupsDavide Libenzi
Introduce keyed event wakeups inside the eventfd code. Signed-off-by: Davide Libenzi <davidel@xmailserver.org> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Miller <davem@davemloft.net> Cc: William Lee Irwin III <wli@movementarian.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01epoll keyed wakeups: teach epoll about hints coming with the wakeup keyDavide Libenzi
Use the events hint now sent by some devices, to avoid unnecessary wakeups for events that are of no interest for the caller. This code handles both devices that are sending keyed events, and the ones that are not (and event the ones that sometimes send events, and sometimes don't). [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Davide Libenzi <davidel@xmailserver.org> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Miller <davem@davemloft.net> Cc: William Lee Irwin III <wli@movementarian.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01epoll keyed wakeups: make sockets use keyed wakeupsDavide Libenzi
Add support for event-aware wakeups to the sockets code. Events are delivered to the wakeup target, so that epoll can avoid spurious wakeups for non-interesting events. Signed-off-by: Davide Libenzi <davidel@xmailserver.org> Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Miller <davem@davemloft.net> Cc: William Lee Irwin III <wli@movementarian.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01epoll keyed wakeups: introduce new *_poll() wakeup macrosDavide Libenzi
Introduce new wakeup macros that allow passing an event mask to the wakeup targets. They exactly mimic their non-_poll() counterpart, with the added event mask passing capability. I did add only the ones currently requested, avoiding the _nr() and _all() for the moment. Signed-off-by: Davide Libenzi <davidel@xmailserver.org> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Miller <davem@davemloft.net> Cc: William Lee Irwin III <wli@movementarian.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01epoll keyed wakeups: add __wake_up_locked_key() and __wake_up_sync_key()Davide Libenzi
This patchset introduces wakeup hints for some of the most popular (from epoll POV) devices, so that epoll code can avoid spurious wakeups on its waiters. The problem with epoll is that the callback-based wakeups do not, ATM, carry any information about the events the wakeup is related to. So the only choice epoll has (not being able to call f_op->poll() from inside the callback), is to add the file* to a ready-list and resolve the real events later on, at epoll_wait() (or its own f_op->poll()) time. This can cause spurious wakeups, since the wake_up() itself might be for an event the caller is not interested into. The rate of these spurious wakeup can be pretty high in case of many network sockets being monitored. By allowing devices to report the events the wakeups refer to (at least the two major classes - POLLIN/POLLOUT), we are able to spare useless wakeups by proper handling inside the epoll's poll callback. Epoll will have in any case to call f_op->poll() on the file* later on, since the change to be done in order to have the full event set sent via wakeup, is too invasive for the way our f_op->poll() system works (the full event set is calculated inside the poll function - there are too many of them to even start thinking the change - also poll/select would need change too). Epoll is changed in a way that both devices which send event hints, and the ones that don't, are correctly handled. The former will gain some efficiency though. As a general rule for devices, would be to add an event mask by using key-aware wakeup macros, when making up poll wait queues. I tested it (together with the epoll's poll fix patch Andrew has in -mm) and wakeups for the supported devices are correctly filtered. Test program available here: http://www.xmailserver.org/epoll_test.c This patch: Nothing revolutionary here. Just using the available "key" that our wakeup core already support. The __wake_up_locked_key() was no brainer, since both __wake_up_locked() and __wake_up_locked_key() are thin wrappers around __wake_up_common(). The __wake_up_sync() function had a body, so the choice was between borrowing the body for __wake_up_sync_key() and calling it from __wake_up_sync(), or make an inline and calling it from both. I chose the former since in most archs it all resolves to "mov $0, REG; jmp ADDR". Signed-off-by: Davide Libenzi <davidel@xmailserver.org> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Miller <davem@davemloft.net> Cc: William Lee Irwin III <wli@movementarian.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01eventfd: improve support for semaphore-like behaviorDavide Libenzi
People started using eventfd in a semaphore-like way where before they were using pipes. That is, counter-based resource access. Where a "wait()" returns immediately by decrementing the counter by one, if counter is greater than zero. Otherwise will wait. And where a "post(count)" will add count to the counter releasing the appropriate amount of waiters. If eventfd the "post" (write) part is fine, while the "wait" (read) does not dequeue 1, but the whole counter value. The problem with eventfd is that a read() on the fd returns and wipes the whole counter, making the use of it as semaphore a little bit more cumbersome. You can do a read() followed by a write() of COUNTER-1, but IMO it's pretty easy and cheap to make this work w/out extra steps. This patch introduces a new eventfd flag that tells eventfd to only dequeue 1 from the counter, allowing simple read/write to make it behave like a semaphore. Simple test here: http://www.xmailserver.org/eventfd-sem.c To be back-compatible with earlier kernels, userspace applications should probe for the availability of this feature via #ifdef EFD_SEMAPHORE fd = eventfd2 (CNT, EFD_SEMAPHORE); if (fd == -1 && errno == EINVAL) <fallback> #else <fallback> #endif Signed-off-by: Davide Libenzi <davidel@xmailserver.org> Cc: <linux-api@vger.kernel.org> Tested-by: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Ulrich Drepper <drepper@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01epoll: use real type instead of void *Tony Battersby
eventpoll.c uses void * in one place for no obvious reason; change it to use the real type instead. Signed-off-by: Tony Battersby <tonyb@cybernetics.com> Acked-by: Davide Libenzi <davidel@xmailserver.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01epoll: clean up ep_modifyTony Battersby
ep_modify() doesn't need to set event.data from within the ep->lock spinlock as the comment suggests. The only place event.data is used is ep_send_events_proc(), and this is protected by ep->mtx instead of ep->lock. Also update the comment for mutex_lock() at the top of ep_scan_ready_list(), which mentions epoll_ctl(EPOLL_CTL_DEL) but not epoll_ctl(EPOLL_CTL_MOD). ep_modify() can also use spin_lock_irq() instead of spin_lock_irqsave(). Signed-off-by: Tony Battersby <tonyb@cybernetics.com> Acked-by: Davide Libenzi <davidel@xmailserver.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01epoll: remove unnecessary xchgTony Battersby
xchg in ep_unregister_pollwait() is unnecessary because it is protected by either epmutex or ep->mtx (the same protection as ep_remove()). If xchg was necessary, it would be insufficient to protect against problems: if multiple concurrent calls to ep_unregister_pollwait() were possible then a second caller that returns without doing anything because nwait == 0 could return before the waitqueues are removed by the first caller, which looks like it could lead to problematic races with ep_poll_callback(). So remove xchg and add comments about the locking. Signed-off-by: Tony Battersby <tonyb@cybernetics.com> Acked-by: Davide Libenzi <davidel@xmailserver.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01epoll: remember the event if epoll_wait returns -EFAULTTony Battersby
If epoll_wait returns -EFAULT, the event that was being returned when the fault was encountered will be forgotten. This is not a big deal since EFAULT will happen only if a buggy userspace program passes in a bad address, in which case what happens later usually doesn't matter. However, it is easy to remember the event for later, and this patch makes a simple change to do that. Signed-off-by: Tony Battersby <tonyb@cybernetics.com> Acked-by: Davide Libenzi <davidel@xmailserver.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01epoll: don't use current in irq contextTony Battersby
ep_call_nested() (formerly ep_poll_safewake()) uses "current" (without dereferencing it) to detect callback recursion, but it may be called from irq context where the use of current is generally discouraged. It would be better to use get_cpu() and put_cpu() to detect the callback recursion. Signed-off-by: Tony Battersby <tonyb@cybernetics.com> Acked-by: Davide Libenzi <davidel@xmailserver.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01epoll: remove debugging codeDavide Libenzi
Remove debugging code from epoll. There's no need for it to be included into mainline code. Signed-off-by: Davide Libenzi <davidel@xmailserver.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01epoll: fix epoll's own poll (update)Davide Libenzi
Signed-off-by: Davide Libenzi <davidel@xmailserver.org> Cc: Pavel Pisa <pisa@cmp.felk.cvut.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01epoll: fix epoll's own pollDavide Libenzi
Fix a bug inside the epoll's f_op->poll() code, that returns POLLIN even though there are no actual ready monitored fds. The bug shows up if you add an epoll fd inside another fd container (poll, select, epoll). The problem is that callback-based wake ups used by epoll does not carry (patches will follow, to fix this) any information about the events that actually happened. So the callback code, since it can't call the file* ->poll() inside the callback, chains the file* into a ready-list. So, suppose you added an fd with EPOLLOUT only, and some data shows up on the fd, the file* mapped by the fd will be added into the ready-list (via wakeup callback). During normal epoll_wait() use, this condition is sorted out at the time we're actually able to call the file*'s f_op->poll(). Inside the old epoll's f_op->poll() though, only a quick check !list_empty(ready-list) was performed, and this could have led to reporting POLLIN even though no ready fds would show up at a following epoll_wait(). In order to correctly report the ready status for an epoll fd, the ready-list must be checked to see if any really available fd+event would be ready in a following epoll_wait(). Operation (calling f_op->poll() from inside f_op->poll()) that, like wake ups, must be handled with care because of the fact that epoll fds can be added to other epoll fds. Test code: /* * epoll_test by Davide Libenzi (Simple code to test epoll internals) * Copyright (C) 2008 Davide Libenzi * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * * Davide Libenzi <davidel@xmailserver.org> * */ #include <sys/types.h> #include <unistd.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <errno.h> #include <signal.h> #include <limits.h> #include <poll.h> #include <sys/epoll.h> #include <sys/wait.h> #define EPWAIT_TIMEO (1 * 1000) #ifndef POLLRDHUP #define POLLRDHUP 0x2000 #endif #define EPOLL_MAX_CHAIN 100L #define EPOLL_TF_LOOP (1 << 0) struct epoll_test_cfg { long size; long flags; }; static int xepoll_create(int n) { int epfd; if ((epfd = epoll_create(n)) == -1) { perror("epoll_create"); exit(2); } return epfd; } static void xepoll_ctl(int epfd, int cmd, int fd, struct epoll_event *evt) { if (epoll_ctl(epfd, cmd, fd, evt) < 0) { perror("epoll_ctl"); exit(3); } } static void xpipe(int *fds) { if (pipe(fds)) { perror("pipe"); exit(4); } } static pid_t xfork(void) { pid_t pid; if ((pid = fork()) == (pid_t) -1) { perror("pipe"); exit(5); } return pid; } static int run_forked_proc(int (*proc)(void *), void *data) { int status; pid_t pid; if ((pid = xfork()) == 0) exit((*proc)(data)); if (waitpid(pid, &status, 0) != pid) { perror("waitpid"); return -1; } return WIFEXITED(status) ? WEXITSTATUS(status): -2; } static int check_events(int fd, int timeo) { struct pollfd pfd; fprintf(stdout, "Checking events for fd %d\n", fd); memset(&pfd, 0, sizeof(pfd)); pfd.fd = fd; pfd.events = POLLIN | POLLOUT; if (poll(&pfd, 1, timeo) < 0) { perror("poll()"); return 0; } if (pfd.revents & POLLIN) fprintf(stdout, "\tPOLLIN\n"); if (pfd.revents & POLLOUT) fprintf(stdout, "\tPOLLOUT\n"); if (pfd.revents & POLLERR) fprintf(stdout, "\tPOLLERR\n"); if (pfd.revents & POLLHUP) fprintf(stdout, "\tPOLLHUP\n"); if (pfd.revents & POLLRDHUP) fprintf(stdout, "\tPOLLRDHUP\n"); return pfd.revents; } static int epoll_test_tty(void *data) { int epfd, ifd = fileno(stdin), res; struct epoll_event evt; if (check_events(ifd, 0) != POLLOUT) { fprintf(stderr, "Something is cooking on STDIN (%d)\n", ifd); return 1; } epfd = xepoll_create(1); fprintf(stdout, "Created epoll fd (%d)\n", epfd); memset(&evt, 0, sizeof(evt)); evt.events = EPOLLIN; xepoll_ctl(epfd, EPOLL_CTL_ADD, ifd, &evt); if (check_events(epfd, 0) & POLLIN) { res = epoll_wait(epfd, &evt, 1, 0); if (res == 0) { fprintf(stderr, "Epoll fd (%d) is ready when it shouldn't!\n", epfd); return 2; } } return 0; } static int epoll_wakeup_chain(void *data) { struct epoll_test_cfg *tcfg = data; int i, res, epfd, bfd, nfd, pfds[2]; pid_t pid; struct epoll_event evt; memset(&evt, 0, sizeof(evt)); evt.events = EPOLLIN; epfd = bfd = xepoll_create(1); for (i = 0; i < tcfg->size; i++) { nfd = xepoll_create(1); xepoll_ctl(bfd, EPOLL_CTL_ADD, nfd, &evt); bfd = nfd; } xpipe(pfds); if (tcfg->flags & EPOLL_TF_LOOP) { xepoll_ctl(bfd, EPOLL_CTL_ADD, epfd, &evt); /* * If we're testing for loop, we want that the wakeup * triggered by the write to the pipe done in the child * process, triggers a fake event. So we add the pipe * read size with EPOLLOUT events. This will trigger * an addition to the ready-list, but no real events * will be there. The the epoll kernel code will proceed * in calling f_op->poll() of the epfd, triggering the * loop we want to test. */ evt.events = EPOLLOUT; } xepoll_ctl(bfd, EPOLL_CTL_ADD, pfds[0], &evt); /* * The pipe write must come after the poll(2) call inside * check_events(). This tests the nested wakeup code in * fs/eventpoll.c:ep_poll_safewake() * By having the check_events() (hence poll(2)) happens first, * we have poll wait queue filled up, and the write(2) in the * child will trigger the wakeup chain. */ if ((pid = xfork()) == 0) { sleep(1); write(pfds[1], "w", 1); exit(0); } res = check_events(epfd, 2000) & POLLIN; if (waitpid(pid, NULL, 0) != pid) { perror("waitpid"); return -1; } return res; } static int epoll_poll_chain(void *data) { struct epoll_test_cfg *tcfg = data; int i, res, epfd, bfd, nfd, pfds[2]; pid_t pid; struct epoll_event evt; memset(&evt, 0, sizeof(evt)); evt.events = EPOLLIN; epfd = bfd = xepoll_create(1); for (i = 0; i < tcfg->size; i++) { nfd = xepoll_create(1); xepoll_ctl(bfd, EPOLL_CTL_ADD, nfd, &evt); bfd = nfd; } xpipe(pfds); if (tcfg->flags & EPOLL_TF_LOOP) { xepoll_ctl(bfd, EPOLL_CTL_ADD, epfd, &evt); /* * If we're testing for loop, we want that the wakeup * triggered by the write to the pipe done in the child * process, triggers a fake event. So we add the pipe * read size with EPOLLOUT events. This will trigger * an addition to the ready-list, but no real events * will be there. The the epoll kernel code will proceed * in calling f_op->poll() of the epfd, triggering the * loop we want to test. */ evt.events = EPOLLOUT; } xepoll_ctl(bfd, EPOLL_CTL_ADD, pfds[0], &evt); /* * The pipe write mush come before the poll(2) call inside * check_events(). This tests the nested f_op->poll calls code in * fs/eventpoll.c:ep_eventpoll_poll() * By having the pipe write(2) happen first, we make the kernel * epoll code to load the ready lists, and the following poll(2) * done inside check_events() will test nested poll code in * ep_eventpoll_poll(). */ if ((pid = xfork()) == 0) { write(pfds[1], "w", 1); exit(0); } sleep(1); res = check_events(epfd, 1000) & POLLIN; if (waitpid(pid, NULL, 0) != pid) { perror("waitpid"); return -1; } return res; } int main(int ac, char **av) { int error; struct epoll_test_cfg tcfg; fprintf(stdout, "\n********** Testing TTY events\n"); error = run_forked_proc(epoll_test_tty, NULL); fprintf(stdout, error == 0 ? "********** OK\n": "********** FAIL (%d)\n", error); tcfg.size = 3; tcfg.flags = 0; fprintf(stdout, "\n********** Testing short wakeup chain\n"); error = run_forked_proc(epoll_wakeup_chain, &tcfg); fprintf(stdout, error == POLLIN ? "********** OK\n": "********** FAIL (%d)\n", error); tcfg.size = EPOLL_MAX_CHAIN; tcfg.flags = 0; fprintf(stdout, "\n********** Testing long wakeup chain (HOLD ON)\n"); error = run_forked_proc(epoll_wakeup_chain, &tcfg); fprintf(stdout, error == 0 ? "********** OK\n": "********** FAIL (%d)\n", error); tcfg.size = 3; tcfg.flags = 0; fprintf(stdout, "\n********** Testing short poll chain\n"); error = run_forked_proc(epoll_poll_chain, &tcfg); fprintf(stdout, error == POLLIN ? "********** OK\n": "********** FAIL (%d)\n", error); tcfg.size = EPOLL_MAX_CHAIN; tcfg.flags = 0; fprintf(stdout, "\n********** Testing long poll chain (HOLD ON)\n"); error = run_forked_proc(epoll_poll_chain, &tcfg); fprintf(stdout, error == 0 ? "********** OK\n": "********** FAIL (%d)\n", error); tcfg.size = 3; tcfg.flags = EPOLL_TF_LOOP; fprintf(stdout, "\n********** Testing loopy wakeup chain (HOLD ON)\n"); error = run_forked_proc(epoll_wakeup_chain, &tcfg); fprintf(stdout, error == 0 ? "********** OK\n": "********** FAIL (%d)\n", error); tcfg.size = 3; tcfg.flags = EPOLL_TF_LOOP; fprintf(stdout, "\n********** Testing loopy poll chain (HOLD ON)\n"); error = run_forked_proc(epoll_poll_chain, &tcfg); fprintf(stdout, error == 0 ? "********** OK\n": "********** FAIL (%d)\n", error); return 0; } Signed-off-by: Davide Libenzi <davidel@xmailserver.org> Cc: Pavel Pisa <pisa@cmp.felk.cvut.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01drivers/misc/isl29003.c: driver for the ISL29003 ambient light sensorDaniel Mack
Add a driver for Intersil's ISL29003 ambient light sensor device plus some documentation. Inspired by tsl2550.c, a driver for a similar device. It is put in drivers/misc for now until the industrial I/O framework gets merged. Signed-off-by: Daniel Mack <daniel@caiaq.de> Acked-by: Jonathan Cameron <jic23@cam.ac.uk> Cc: Jean Delvare <khali@linux-fr.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01hpilo: reduce frequency of IO operationsDavid Altobelli
Change hpilo open and close logic to spin for 10usec between checking device, rather than every usec. Because the loop is coded to take up to 10ms, it seemed prudent to increase the interval between polling the device, to reduce the load on the system and allow more other work to happen. Signed-off-by: David Altobelli <david.altobelli@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01ntfs: remove private wrapper of endian helpersHarvey Harrison
The base versions handle constant folding now and are shorter than these private wrappers, use them directly. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Cc: Anton Altaparmakov <aia21@cantab.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01introduce pr_cont() macroCyrill Gorcunov
We cover all log-levels by pr_... macros except KERN_CONT one. Add it for convenience. Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01init/main.c: fix sparse warnings: context imbalanceHannes Eder
Impact: Attribute function 'init_post' with __releases(...). Fix these sparse warnings: init/main.c:805:21: warning: context imbalance in 'init_post' - unexpected unlock init/main.c:899:9: warning: context imbalance in 'kernel_init' - wrong count at exit Signed-off-by: Hannes Eder <hannes@hanneseder.net> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01bcm47xx: fix GPIO API return codesMichael Buesch
The GPIO API is supposed to return 0 or a negative error code, but the SSB GPIO functions return the bitmask of the GPIO register. Fix this by ignoring the bitmask and always returning 0. The SSB GPIO functions can't fail. Signed-off-by: Michael Buesch <mb@bu3sch.de> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: David Brownell <david-b@pacbell.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01auxdisplay: remove PARPORT dependencyH Hartley Sweeten
Remove PARPORT dependency for Auxiliary Display support. This is not needed since the dependency for the KS0108 driver is PARPORT_PC. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Miguel Ojeda Sandonis <miguel.ojeda.sandonis@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01remove unused include/asm-generic/dma-mapping.hFUJITA Tomonori
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01filesystem freeze: allow SysRq emergency thaw to thaw frozen filesystemsEric Sandeen
Now that the filesystem freeze operation has been elevated to the VFS, and is just an ioctl away, some sort of safety net for unintentionally frozen root filesystems may be in order. The timeout thaw originally proposed did not get merged, but perhaps something like this would be useful in emergencies. For example, freeze /path/to/mountpoint may freeze your root filesystem if you forgot that you had that unmounted. I chose 'j' as the last remaining character other than 'h' which is sort of reserved for help (because help is generated on any unknown character). I've tested this on a non-root fs with multiple (nested) freezers, as well as on a system rendered unresponsive due to a frozen root fs. [randy.dunlap@oracle.com: emergency thaw only if CONFIG_BLOCK enabled] Signed-off-by: Eric Sandeen <sandeen@redhat.com> Cc: Takashi Sato <t-sato@yk.jp.nec.com> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01lib/rbtree.c: optimize rb_erase()Wolfram Strepp
Tfour 4 redundant if-conditions in function __rb_erase_color() in lib/rbtree.c are removed. In pseudo-source-code, the structure of the code is as follows: if ((!A || B) && (!C || D)) { . . . } else { if (!C || D) {//if this is true, it implies: (A == true) && (B == false) if (A) {//hence this always evaluates to 'true'... . } . //at this point, C always becomes true, because of: __rb_rotate_right/left(); //and: other = parent->rb_right/left; } . . if (C) {//...and this too ! . } } Signed-off-by: Wolfram Strepp <wstrepp@gmx.de> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Andrea Arcangeli <andrea@qumranet.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01loop: add ioctl to resize a loop deviceJ. R. Okajima
Add the ability to 'resize' the loop device on the fly. One practical application is a loop file with XFS filesystem, already mounted: You can easily enlarge the file (append some bytes) and then call ioctl(fd, LOOP_SET_CAPACITY, new); The loop driver will learn about the new size and you can use xfs_growfs later on, which will allow you to use full capacity of the loop file without the need to unmount. Test app: #include <linux/fs.h> #include <linux/loop.h> #include <sys/ioctl.h> #include <sys/stat.h> #include <sys/types.h> #include <assert.h> #include <errno.h> #include <fcntl.h> #include <stdio.h> #include <stdlib.h> #include <unistd.h> #define _GNU_SOURCE #include <getopt.h> char *me; void usage(FILE *f) { fprintf(f, "%s [options] loop_dev [backend_file]\n" "-s, --set new_size_in_bytes\n" "\twhen backend_file is given, " "it will be expanded too while keeping the original contents\n", me); } struct option opts[] = { { .name = "set", .has_arg = 1, .flag = NULL, .val = 's' }, { .name = "help", .has_arg = 0, .flag = NULL, .val = 'h' } }; void err_size(char *name, __u64 old) { fprintf(stderr, "size must be larger than current %s (%llu)\n", name, old); } int main(int argc, char *argv[]) { int fd, err, c, i, bfd; ssize_t ssz; size_t sz; __u64 old, new, append; char a[BUFSIZ]; struct stat st; FILE *out; char *backend, *dev; err = EINVAL; out = stderr; me = argv[0]; new = 0; while ((c = getopt_long(argc, argv, "s:h", opts, &i)) != -1) { switch (c) { case 's': errno = 0; new = strtoull(optarg, NULL, 0); if (errno) { err = errno; perror(argv[i]); goto out; } break; case 'h': err = 0; out = stdout; goto err; default: perror(argv[i]); goto err; } } if (optind < argc) dev = argv[optind++]; else goto err; fd = open(dev, O_RDONLY); if (fd < 0) { err = errno; perror(dev); goto out; } err = ioctl(fd, BLKGETSIZE64, &old); if (err) { err = errno; perror("ioctl BLKGETSIZE64"); goto out; } if (!new) { printf("%llu\n", old); goto out; } if (new < old) { err = EINVAL; err_size(dev, old); goto out; } if (optind < argc) { backend = argv[optind++]; bfd = open(backend, O_WRONLY|O_APPEND); if (bfd < 0) { err = errno; perror(backend); goto out; } err = fstat(bfd, &st); if (err) { err = errno; perror(backend); goto out; } if (new < st.st_size) { err = EINVAL; err_size(backend, st.st_size); goto out; } append = new - st.st_size; sz = sizeof(a); while (append > 0) { if (append < sz) sz = append; ssz = write(bfd, a, sz); if (ssz != sz) { err = errno; perror(backend); goto out; } append -= sz; } err = fsync(bfd); if (err) { err = errno; perror(backend); goto out; } } err = ioctl(fd, LOOP_SET_CAPACITY, new); if (err) { err = errno; perror("ioctl LOOP_SET_CAPACITY"); } goto out; err: usage(out); out: return err; } Signed-off-by: J. R. Okajima <hooanon05@yahoo.co.jp> Signed-off-by: Tomas Matejicek <tomas@slax.org> Cc: <util-linux-ng@vger.kernel.org> Cc: Karel Zak <kzak@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Cc: Akinobu Mita <akinobu.mita@gmail.com> Cc: <linux-api@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01uml: remove useless commentsWANG Cong
These comments are useless now, remove them. Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01uml: improve error messagesWANG Cong
These error messages are from check_sysemu(), not check_ptrace(). Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01uml: don't use a too long string literalWANG Cong
uml uses a concatenated string literal to store the contents of .config, but .config file content is varaible, it can be very long. Use an array of string literals instead. Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01ubd: stop defintining MAJOR_NRChristoph Hellwig
MAJOR_NR isn't needed anymore since very early 2.5 kernels. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01pm: cleanup includesMagnus Damm
Remove unused/duplicate cruft from asm/suspend.h: - x86_32: remove unused acpi code - powerpc: remove duplicate prototypes, see linux/suspend.h Signed-off-by: Magnus Damm <damm@igel.co.jp> Cc: Paul Mundt <lethal@linux-sh.org> Acked-by: "Rafael J. Wysocki" <rjw@sisk.pl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01pm: rework includes, remove arch ifdefsMagnus Damm
Make the following header file changes: - remove arch ifdefs and asm/suspend.h from linux/suspend.h - add asm/suspend.h to disk.c (for arch_prepare_suspend()) - add linux/io.h to swsusp.c (for ioremap()) - x86 32/64 bit compile fixes Signed-off-by: Magnus Damm <damm@igel.co.jp> Cc: Paul Mundt <lethal@linux-sh.org> Acked-by: "Rafael J. Wysocki" <rjw@sisk.pl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01alpha: convert u64 to unsigned long longRandy Dunlap
Convert alpha architecture to use u64 as unsigned long long. This is being done so that (a) all arches use u64 as unsigned long long and (b) printk of a u64 as %ll[ux] will not generate format warnings by gcc. The only gcc cross-compiler that I have is 4.0.2, which generates errors about miscompiling __weak references, so I have commented out that line in compiler-gcc4.h so that most of these compile, but more builds and real machine testing would be Real Good. [akpm@linux-foundation.org: fix warning] [akpm@linux-foundation.org: fix build] [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> From: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01alpha: xchg/cmpxchg cleanup and fixesIvan Kokshaysky
- "_local" versions of xchg/cmpxchg functions duplicate code of non-local ones (quite a few pages of assembler), except memory barriers. We can generate these two variants from a single header file using simple macros; - convert xchg macro back to inline function using always_inline attribute; - use proper argument types for cmpxchg_u8/u16 functions to fix a problem with negative arguments. Signed-off-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Richard Henderson <rth@twiddle.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01MAINTAINERS: add the missing linux alpha port mailling listCheng Renquan
Signed-off-by: Cheng Renquan <crquan@gmail.com> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>