Several subsystem open handlers dereference the fops_get() return value
without checking it for nullness. This opens a race condition between the
open handler and module unloading.
A module can be marked as being unloaded (MODULE_STATE_GOING) before its
exit function is called and gets the chance to unregister the driver.
During that window open handlers can still be called, and fops_get() will
fail in try_module_get() and return a NULL pointer.
This change checks the fops_get() return value and returns -ENODEV if NULL.
Reported-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
Signed-off-by: Laurent Pinchart <laurent.pinchart@skynet.be>
Acked-by: Takashi Iwai <tiwai@suse.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dave Airlie <airlied@linux.ie>
Acked-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Today's linux-next build (x86_64 allmodconfig) failed like this:
drivers/media/dvb/dvb-core/dvbdev.c: In function 'dvb_register_device':
drivers/media/dvb/dvb-core/dvbdev.c:254: error: implicit declaration of function 'nums2minor'
Caused by commit f3d9182030d9655d9ffff33dfceb45b4a127b6ec ("V4L/DVB
(9361): Dynamic DVB minor allocation") which clearly has not even been
built with CONFIG_DVB_DYNAMIC_MINORS=y.
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This allows udev to create proper device nodes without any
hacky shell scripts/programs to call, which guess these numbers
from the kernel device names.
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Implement dynamic minor allocation for DVB, to allow more than four
devices of the same type per adapter, based on drivers/usb/core/file.c.
Add a new config option, DVB_DYNAMIC_MINORS, to make use of this
feature, which defaults to no for backwards compatibility.
Signed-off-by: Andreas Oberritter <obi@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This add frontend R/W mutual exclusion.
Prior to this point in time it was possible to open both
frontends simultaneously which an MFE card cannot support.
In order to stop this, a delayed open is performed which
has the following function:
- Return EBUSY after a configurable amount of time
if a frontend is unavailable due to the other being
in use.
- Only allow opening of a frontend if the kernel thread
of the other has stopped.
This solution was chosen to allow switching between
frontends to work as seamlessly as possible. When both
frontends are actually opened simultaneously then one
will only open, but if quick switching is performed
between one of many then the new open will succeed in
a clean fashion rather than interrupting a kernel
thread.
Signed-off-by: Darron Broad <darron@kewl.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
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>
The adapter_nr module options can be used to allocate static adapter
numbers on a driver level. It avoids problems with changing DVB apapter
numbers after warm/cold boot or device unplugging and repluging.
Each driver holds DVB_MAX_ADAPTER long array of the preferred order of
adapter numbers.
options dvb-usb-dib0700 adapter_nr=7,6,5,4,3,2,1,0 would result in a
reversed allocation of adapter numbers.
With adapter_nr=2,5 it tries first to get adapter number 2 and 5. If
both are already in use it will allocate the lowest free adapter number.
Signed-off-by: Janne Grunau <janne-dvb@grunau.be>
Acked-by: Hermann Pitton <hermann.pitton@arcor.de>
Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Acked-by: Oliver Endriss <o.endriss@gmx.de>
Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
struct cdev does not need the kobject name to be set, as it is never
used. This patch fixes up the few places it is set.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Since at least kernel 2.6.12-rc2, module.h includes moduleparm.h. This
patch removes all occurences of moduleparm.h from drivers/media files.
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
The currently used "struct class_device" will be removed from the
kernel. Here is a trivial patch that converts DVB to use struct device.
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
All the printks had missing level prefixes so I've fixed these too.
Also fixed some grammer errors.
Signed-off-by: Simon Arlott <simon@fire.lp0.eu>
Signed-off-by: Trent Piepho <xyzzy@speakeasy.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
dvb-core is not started early enough when device drivers that use dvb are
compiled in so dvb_register_device fails (silently) since dvb_class is
NULL, this runs dvb_init using subsys_initcall instead of module_init.
dvb_register_device will now check the return value of class_device_create.
Signed-off-by: Simon Arlott <simon@fire.lp0.eu>
Signed-off-by: Trent Piepho <xyzzy@speakeasy.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Fix several instances of dvb-core functions using mutex_lock_interruptible
and returning -ERESTARTSYS where the calling function will either never
retry or never check the return value.
These cause a race condition with dvb_dmxdev_filter_free and
dvb_dvr_release, both of which are filesystem release functions whose
return value is ignored and will never be retried. When this happens it
becomes impossible to open dvr0 again (-EBUSY) since it has not been
released properly.
Signed-off-by: Simon Arlott <simon@fire.lp0.eu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-By: Johannes Stezenbach <js@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Arjan van de Ven <arjan@infradead.org> reported an illegal re-usage of
the fileoperations struct if more than one dvb device (e.g. frontend) is
present.
This patch fixes this issue.
It allocates a new fileoperations struct each time a device is
registered and copies the default template fileops.
Signed-off-by: Marcel Siegert <mws@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
After Al Viro (finally) succeeded in removing the sched.h #include in module.h
recently, it makes sense again to remove other superfluous sched.h includes.
There are quite a lot of files which include it but don't actually need
anything defined in there. Presumably these includes were once needed for
macros that used to live in sched.h, but moved to other header files in the
course of cleaning it up.
To ease the pain, this time I did not fiddle with any header files and only
removed #includes from .c-files, which tend to cause less trouble.
Compile tested against 2.6.20-rc2 and 2.6.20-rc2-mm2 (with offsets) on alpha,
arm, i386, ia64, mips, powerpc, and x86_64 with allnoconfig, defconfig,
allmodconfig, and allyesconfig as well as a few randconfigs on x86_64 and all
configs in arch/arm/configs on arm. I also checked that no new warnings were
introduced by the patch (actually, some warnings are removed that were emitted
by unnecessarily included header files).
Signed-off-by: Tim Schmielau <tim@physik3.uni-rostock.de>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently in /sys/class/dvb/dvbX.demuxY/ we have:
dev
uevent
With the patch, we have (for a PCI DVB device):
dev
device -> ../../../devices/pci0000:00/0000:00:1e.0/0000:03:0d.0
uevent
So userspace tools can (finally) work out which physical device a DVB adapter
refers to. Previously you had to kinda look through dmesg and hope that it
hadn't been dumped out of the buffer. This makes debugging a lot easier if
the system has been up for a long time!
This is done by adding an extra 'struct device *' parameter to
dvb_register_adapter(). It will work with any kind of standard
linux 'device'. Additionally, if someone has an embedded system which does
things differently, they can simply supply 'NULL' and the behaviour will be
as before - the link will simply not appear.
Ack'd-by: Manu Abraham <manu@linuxtv.org>
Acked-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Andrew de Quincey <adq_dvb@lidskialf.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
This mutex is meant to stop two devices getting the same ID. dvbdev_get_free_id()
scans the list of already allocated devices to find a free id.
Unfortunately, since the mutex is unlocked before the card is added to the
above list, it is still possible for two of them to get the same id.
Its debatable whether this mutex lock is actually needed, but I'm unwilling
to just remove it in case something does depend on it.
Signed-off-by: Andrew de Quincey <adq_dvb@lidskialf.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Mark the f_ops members of inodes as const, as well as fix the
ripple-through this causes by places that copy this f_ops and then "do
stuff" with it.
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- Semaphore to mutex conversion.
The conversion was generated via scripts, and the result was validated
automatically via a script as well.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
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>
Modified dvb_register_adapter() to avoid kmalloc/kfree. Drivers have to embed
struct dvb_adapter into their private data struct from now on. (Andreas
Oberritter)
Signed-off-by: Johannes Stezenbach <js@linuxtv.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
