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2019-12-17ppdev: fix PPGETTIME/PPSETTIME ioctlsArnd Bergmann1-4/+12
commit 998174042da229e2cf5841f574aba4a743e69650 upstream. Going through the uses of timeval in the user space API, I noticed two bugs in ppdev that were introduced in the y2038 conversion: * The range check was accidentally moved from ppsettime to ppgettime * On sparc64, the microseconds are in the other half of the 64-bit word. Fix both, and mark the fix for stable backports. Cc: stable@vger.kernel.org Fixes: 3b9ab374a1e6 ("ppdev: convert to y2038 safe") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/r/20191108203435.112759-8-arnd@arndb.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17ppdev: remove unused ROUND_UP macroGuoqing Jiang1-3/+0
This macro is not used after commit 3b9ab374a1e6 ("ppdev: convert to y2038 safe"), so let's remove it. Signed-off-by: Guoqing Jiang <gqjiang@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-16ppdev: fix registering same device nameSudip Mukherjee1-2/+9
Usually every parallel port will have a single pardev registered with it. But ppdev driver is an exception. This userspace parallel port driver allows to create multiple parrallel port devices for a single parallel port. And as a result we were having a big warning like: "sysfs: cannot create duplicate filename '/devices/parport0/ppdev0.0'". And with that many parallel port printers stopped working. We have been using the minor number as the id field while registering a parralel port device with a parralel port. But when there are multiple parrallel port device for one single parallel port, they all tried to register with the same name like 'pardev0.0' and everything started failing. Use an incremented index as the id instead of the minor number. Fixes: 8b7d3a9d903e ("ppdev: use new parport device model") Cc: stable <stable@vger.kernel.org> # v4.9+ Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1414656 Bugzilla: https://bugs.archlinux.org/task/52322 Tested-by: James Feeney <james@nurealm.net> Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-02sched/headers: Prepare to move signal wakeup & sigpending methods from ↵Ingo Molnar1-1/+1
<linux/sched.h> into <linux/sched/signal.h> Fix up affected files that include this signal functionality via sched.h. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-11ppdev: don't print a free'd stringColin Ian King1-5/+8
A previous fix of a memory leak now prints the string 'name' that was previously free'd. Fix this by free'ing the string at the end of the function and adding an error exit path for the error conditions. CoverityScan CID#1384523 ("Use after free") Fixes: 2bd362d5f45c1 ("ppdev: fix memory leak") Signed-off-by: Colin Ian King <colin.king@canonical.com> Acked-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-29ppdev: check before attaching portSudip Mukherjee1-2/+21
After parport starts using the device model, all pardevice drivers should decide in their match_port callback function if they want to attach with that particulatr port. ppdev has been converted to use the new parport device-model code but pp_attach() tried to attach with all the ports. Create a new array of pointer and use that to remember the ports we have attached. And use that information to skip attaching ports which we have already attached. Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-29ppdev: use pr_* macrosSudip Mukherjee1-6/+5
The coding style recommends not to use printk. Use pr_* macros. Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-29ppdev: fix memory leakSudip Mukherjee1-1/+1
The variable name was only released if parport_register_dev_model() fails. Now that we are using the device-model the parport driver will duplicate the name and use it. So we can release the variable after the device has been registered with the parport. Suggested-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-10ppdev: fix double-free of pp->pdev->nameJann Horn1-3/+0
free_pardevice() is called by parport_unregister_device() and already frees pp->pdev->name, don't try to do it again. This bug causes kernel crashes. I found and verified this with KASAN and some added pr_emerg()s: [ 60.316568] pp_release: pp->pdev->name == ffff88039cb264c0 [ 60.316692] free_pardevice: freeing par_dev->name at ffff88039cb264c0 [ 60.316706] pp_release: kfree(ffff88039cb264c0) [ 60.316714] ========================================================== [ 60.316722] BUG: Double free or freeing an invalid pointer [ 60.316731] Unexpected shadow byte: 0xFB [ 60.316801] Object at ffff88039cb264c0, in cache kmalloc-32 size: 32 [ 60.316813] Allocated: [ 60.316824] PID = 1695 [ 60.316869] Freed: [ 60.316880] PID = 1695 [ 60.316935] ========================================================== Signed-off-by: Jann Horn <jann@thejh.net> Acked-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31ppdev: use new parport device modelSudip Mukherjee1-5/+20
Modify ppdev driver to use the new parallel port device model. Initially submitted and committed as: e7223f186033 ("ppdev: use new parport device model") But due to some regression it was reverted by: 1701f680407c ("Revert "ppdev: use new parport device model"") Now that the original source of regression is fixed by: bbca503b2ee0 ("parport: use subsys_initcall") we can again modify ppdev to use device model. Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-25Revert "ppdev: use new parport device model"Linus Torvalds1-20/+5
This reverts commit e7223f18603374d235d8bb0398532323e5f318b9. It causes problems when a ppdev tries to register before the parport driver has been registered with the device model. That will trigger the BUG_ON(!drv->bus->p); at drivers/base/driver.c:153. The call chain is kernel_init -> kernel_init_freeable -> do_one_initcall -> ppdev_init -> __parport_register_driver -> driver_register *BOOM* Reported-by: kernel test robot <fengguang.wu@intel.com> Reported-by: Ross Zwisler <zwisler@gmail.com> Reported-by: Petr Mladek <pmladek@suse.com> Cc: Sudip Mukherjee <sudipm.mukherjee@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-02-15ppdev: use dev_* macrosSudip Mukherjee1-7/+7
It is more preffered to use the dev_* family of macros instead of using the generic pr_*. Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-15ppdev: use new parport device modelSudip Mukherjee1-5/+20
Modify ppdev driver to use the new parallel port device model. Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-15ppdev: remove space before tabSudip Mukherjee1-1/+1
For alignment we should use tab in all possible places. checkpatch was complaining for using space before tab. Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-15ppdev: fix parenthesis alignmentSudip Mukherjee1-13/+13
checkpatch was complaining that the alignment was not matching with the open parenthesis. Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-15ppdev: remove bracesSudip Mukherjee1-35/+22
For single statement if and else blocks we do not need braces. Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-15ppdev: add missing blank lineSudip Mukherjee1-0/+6
kernel coding style recommends a blank line after varaiable declaration. Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-15ppdev: remove whitespace around pointersSudip Mukherjee1-12/+12
checkpatch was complaining about space around the pointer. Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-15ppdev: space prohibited between function name and parenthesisSudip Mukherjee1-96/+96
checkpatch was complaining about space between function name and open parenthesis. Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-09ppdev: add support for compat ioctlBamvor Jian Zhang1-0/+12
The arg of ioctl in ppdev is the pointer of integer except the timeval in PPSETTIME, PPGETTIME. Different size of timeval is already supported by the previous patches. So, it is safe to add compat support. Signed-off-by: Bamvor Jian Zhang <bamvor.zhangjian@linaro.org> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Tested-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-09ppdev: convert to y2038 safeBamvor Jian Zhang1-20/+55
The y2038 issue for ppdev is changes of timeval in the ioctl (PPSETTIME and PPGETTIME). The size of struct timeval changes from 8bytes to 16bytes due to the changes of time_t. It lead to the changes of the command of ioctl, e.g. for PPGETTIME, We have: on 32-bit (old): 0x80087095 on 32-bit (new): 0x80107095 on 64-bit : 0x80107095 This patch define these two ioctl commands to support the 32bit and 64bit time_t application at the same time. And, introduce pp_set_timeout to remove some duplicated code. Signed-off-by: Bamvor Jian Zhang <bamvor.zhangjian@linaro.org> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Tested-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-02-23new helper: file_inode(file)Al Viro1-3/+3
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-28Merge branch 'master' into for-nextJiri Kosina1-1/+2
Sync up with Linus' tree to be able to apply Cesar's patch against newer version of the code. Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-10-16parport: dead code in pp_writeAlan Cox1-5/+1
We always update bytes_written before we check signal_pending so it follows that we can't get a signal return for 0 bytes so we don't need to check in the singal path. The cases a signal causes an earlier abort are handled before this and will not hit this path Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-09-06ppdev: ppdev_init: do not return zero in case of failureAlexey Khoroshilov1-1/+2
Error handling of parport_register_driver() in ppdev_init() is broken because it deallocates all resources but still returns zero. Currently parport_register_driver() always succeeds. Nevertheless it is worth to fix the issue. Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2011-05-27drivers/char/ppdev.c: put gotten port valueJulia Lawall1-0/+1
parport_find_number() calls parport_get_port() on its result, so there should be a corresponding call to parport_put_port() before dropping the reference. Similar code is found in the function register_device() in the same file. The semantic match that finds this problem is as follows: (http://coccinelle.lip6.fr/) // <smpl> @exists@ local idexpression struct parport * x; expression ra,rr; statement S1,S2; @@ x = parport_find_number(...) ... when != x = rr when any when != parport_put_port(x,...) when != if (...) { ... parport_put_port(x,...) ...} ( if(<+...x...+>) S1 else S2 | if(...) { ... when != x = ra when forall when != parport_put_port(x,...) *return...; } ) // </smpl> Signed-off-by: Julia Lawall <julia@diku.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-28drivers/char/ppdev.c: fix information leak to userlandVasiliy Kulikov1-0/+1
Structure par_timeout is copied to userland with some padding fields unitialized. Field tv_usec has type __kernel_suseconds_t, it differs from tv_sec's type on some architectures. It leads to leaking of stack memory. Signed-off-by: Vasiliy Kulikov <segooon@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-05drivers: autoconvert trivial BKL users to private mutexArnd Bergmann1-4/+4
All these files use the big kernel lock in a trivial way to serialize their private file operations, typically resulting from an earlier semi-automatic pushdown from VFS. None of these drivers appears to want to lock against other code, and they all use the BKL as the top-level lock in their file operations, meaning that there is no lock-order inversion problem. Consequently, we can remove the BKL completely, replacing it with a per-file mutex in every case. Using a scripted approach means we can avoid typos. These drivers do not seem to be under active maintainance from my brief investigation. Apologies to those maintainers that I have missed. file=$1 name=$2 if grep -q lock_kernel ${file} ; then if grep -q 'include.*linux.mutex.h' ${file} ; then sed -i '/include.*<linux\/smp_lock.h>/d' ${file} else sed -i 's/include.*<linux\/smp_lock.h>.*$/include <linux\/mutex.h>/g' ${file} fi sed -i ${file} \ -e "/^#include.*linux.mutex.h/,$ { 1,/^\(static\|int\|long\)/ { /^\(static\|int\|long\)/istatic DEFINE_MUTEX(${name}_mutex); } }" \ -e "s/\(un\)*lock_kernel\>[ ]*()/mutex_\1lock(\&${name}_mutex)/g" \ -e '/[ ]*cycle_kernel_lock();/d' else sed -i -e '/include.*\<smp_lock.h\>/d' ${file} \ -e '/cycle_kernel_lock()/d' fi Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2010-05-27drivers/char/ppdev.c: use kasprintfJulia Lawall1-3/+1
kasprintf combines kmalloc and sprintf, and takes care of the size calculation itself. The semantic patch that makes this change is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ expression a,flag; expression list args; statement S; @@ a = - \(kmalloc\|kzalloc\)(...,flag) + kasprintf(flag,args) <... when != a if (a == NULL || ...) S ...> - sprintf(a,args); // </smpl> Signed-off-by: Julia Lawall <julia@diku.dk> Cc: Michael Buesch <mb@bu3sch.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo1-0/+1
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2009-06-19ppdev: reduce kernel log spamMichael Buesch1-18/+11
One of my programs frequently grabs the parport, does something with it and then drops it again. This results in spamming of the kernel log with "... registered pardevice" "... unregistered pardevice" These messages are completely useless, except for debugging ppdev, probably. So put them under DEBUG (or dynamic debug). Signed-off-by: Michael Buesch <mb@bu3sch.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16device create: char: convert device_create_drvdata to device_createGreg Kroah-Hartman1-3/+2
Now that device_create() has been audited, rename things back to the original call to be sane. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-25ppdev: wrap ioctl handler in driver and push lock downAlan Cox1-5/+13
Signed-off-by: Alan Cox <alan@redhat.com> Cc: Jiri Slaby <jirislaby@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-22device create: char: convert device_create to device_create_drvdataGreg Kroah-Hartman1-2/+3
device_create() is race-prone, so use the race-free device_create_drvdata() instead as device_create() is going away. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-06-21Add a bunch of cycle_kernel_lock() callsJonathan Corbet1-1/+2
All of the open() functions which don't need the BKL on their face may still depend on its acquisition to serialize opens against driver initialization. So make those functions acquire then release the BKL to be on the safe side. Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2008-06-21Add "no BKL needed" comments to several driversJonathan Corbet1-0/+1
This documents the fact that somebody looked at the relevant open() functions and concluded that, due to their trivial nature, no locking was needed. Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2007-10-24[PARPORT] Remove unused 'irq' argument from parport irq functionsJeff Garzik1-2/+2
None of the drivers with a struct pardevice's ->irq_func() hook ever used the 'irq' argument passed to it, so remove it. Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2007-10-17Clean up duplicate includes in drivers/char/Jesper Juhl1-1/+0
This patch cleans up duplicate includes in drivers/char/ Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08header cleaning: don't include smp_lock.h when not usedRandy Dunlap1-1/+0
Remove includes of <linux/smp_lock.h> where it is not used/needed. Suggested by Al Viro. Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc, sparc64, and arm (all 59 defconfigs). 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>
2007-05-08layered parport code uses parport->devDavid Brownell1-1/+1
Update some of the layered parport_driver code to use parport->dev: - i2c-parport (parent of i2c_adapter) - spi_butterfly (parent of spi_master, allowing cruft removal) - lp (creating class_device) - ppdev (parent of parportN device) - tipar (creating class_device) There are still drivers that should be updated, like some of the input drivers; but they won't be any worse off than they are today. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Greg KH <greg@kroah.com> 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>
2006-12-08[PATCH] struct path: convert char-driversJosef Sipek1-2/+2
Signed-off-by: Josef Sipek <jsipek@fsl.cs.sunysb.edu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-02Driver core: convert ppdev code to use struct deviceGreg Kroah-Hartman1-3/+3
Converts from using struct "class_device" to "struct device" making everything show up properly in /sys/devices/ with symlinks from the /sys/class directory. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-10-05IRQ: Maintain regs pointer globally rather than passing to IRQ handlersDavid Howells1-1/+1
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead of passing regs around manually through all ~1800 interrupt handlers in the Linux kernel. The regs pointer is used in few places, but it potentially costs both stack space and code to pass it around. On the FRV arch, removing the regs parameter from all the genirq function results in a 20% speed up of the IRQ exit path (ie: from leaving timer_interrupt() to leaving do_IRQ()). Where appropriate, an arch may override the generic storage facility and do something different with the variable. On FRV, for instance, the address is maintained in GR28 at all times inside the kernel as part of general exception handling. Having looked over the code, it appears that the parameter may be handed down through up to twenty or so layers of functions. Consider a USB character device attached to a USB hub, attached to a USB controller that posts its interrupts through a cascaded auxiliary interrupt controller. A character device driver may want to pass regs to the sysrq handler through the input layer which adds another few layers of parameter passing. I've build this code with allyesconfig for x86_64 and i386. I've runtested the main part of the code on FRV and i386, though I can't test most of the drivers. I've also done partial conversion for powerpc and MIPS - these at least compile with minimal configurations. This will affect all archs. Mostly the changes should be relatively easy. Take do_IRQ(), store the regs pointer at the beginning, saving the old one: struct pt_regs *old_regs = set_irq_regs(regs); And put the old one back at the end: set_irq_regs(old_regs); Don't pass regs through to generic_handle_irq() or __do_IRQ(). In timer_interrupt(), this sort of change will be necessary: - update_process_times(user_mode(regs)); - profile_tick(CPU_PROFILING, regs); + update_process_times(user_mode(get_irq_regs())); + profile_tick(CPU_PROFILING); I'd like to move update_process_times()'s use of get_irq_regs() into itself, except that i386, alone of the archs, uses something other than user_mode(). Some notes on the interrupt handling in the drivers: (*) input_dev() is now gone entirely. The regs pointer is no longer stored in the input_dev struct. (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does something different depending on whether it's been supplied with a regs pointer or not. (*) Various IRQ handler function pointers have been moved to type irq_handler_t. Signed-Off-By: David Howells <dhowells@redhat.com> (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-07-04[PATCH] make more file_operation structs staticArjan van de Ven1-1/+1
Mark the static struct file_operations in drivers/char as const. Making them const prevents accidental bugs, and moves them to the .rodata section so that they no longer do any false sharing; in addition with the proper debug option they are then protected against corruption.. [akpm@osdl.org: build fix] Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] devfs: Remove the devfs_fs_kernel.h file from the treeGreg Kroah-Hartman1-1/+0
Also fixes up all files that #include it. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-26[PATCH] devfs: Remove devfs_remove() function from the kernel treeGreg Kroah-Hartman1-8/+1
Removes the devfs_remove() function and all callers of it. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-26[PATCH] devfs: Remove devfs_mk_cdev() function from the kernel treeGreg Kroah-Hartman1-4/+0
Removes the devfs_mk_cdev() function and all callers of it. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-26[PATCH] devfs: Remove devfs_mk_dir() function from the kernel treeGreg Kroah-Hartman1-1/+0
Removes the devfs_mk_dir() function and all callers of it. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-25[PATCH] parport: move PP_MAJOR from ppdev.h to major.hRene Herman1-1/+2
Today I wondered about /dev/parport<n> after not seeing anything in drivers/parport register char-major-99. Having PP_MAJOR in include/linux/major.h would've allowed me to more quickly determine that it was the ppdev driver driving these. Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-28[PATCH] Driver Core: fix up all callers of class_device_create()Greg Kroah-Hartman1-1/+1
The previous patch adding the ability to nest struct class_device changed the paramaters to the call class_device_create(). This patch fixes up all in-kernel users of the function. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>