When the loop terminates with size == 0 in rng_dev_read we will
unlock the rng mutex twice.
Reported-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

This patch prevents the hw_random core using too small of a buffer
on machines with small cacheline sizes.
Signed-off-by: NIan Molton <ian.molton@collabora.co.uk>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

This patch implements a new method by which hw_random hardware drivers
can pass data to the core more efficiently, using a shared buffer.

The old methods have been retained as a compatability layer until all the
drivers have been updated.
Signed-off-by: NIan Molton <ian.molton@collabora.co.uk>
Acked-by: NMatt Mackall <mpm@selenic.com>
Acked-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

hw_random core is completely serialized with rng_mutex. No need for
the cycle_kernel_lock() magic.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
LKML-Reference: <20091010153349.844488872@linutronix.de>
Cc: Herbert Xu <herbert@gondor.apana.org.au>

This allows subsytems to provide devtmpfs with non-default permissions
for the device node. Instead of the default mode of 0600, null, zero,
random, urandom, full, tty, ptmx now have a mode of 0666, which allows
non-privileged processes to access standard device nodes in case no
other userspace process applies the expected permissions.

This also fixes a wrong assignment in pktcdvd and a checkpatch.pl complain.
Signed-off-by: NKay Sievers <kay.sievers@vrfy.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This adds support for misc devices to report their requested nodename to
userspace.  It also updates a number of misc drivers to provide the
needed subdirectory and device name to be used for them.
Signed-off-by: NKay Sievers <kay.sievers@vrfy.org>
Signed-off-by: NJan Blunck <jblunck@suse.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Signed-off-by: NArnd Bergmann <arnd@arndb.de>

After 2.6.24 there was a plan to make the PM core acquire all device
semaphores during a suspend/hibernation to protect itself from
concurrent operations involving device objects.  That proved to be
too heavy-handed and we found a better way to achieve the goal, but
before it happened, we had introduced the functions
device_pm_schedule_removal() and destroy_suspended_device() to allow
drivers to "safely" destroy a suspended device and we had adapted some
drivers to use them.  Now that these functions are no longer necessary,
it seems reasonable to remove them and modify their users to use the
normal device unregistration instead.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Acked-by: NPavel Machek <pavel@ucw.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The api for hardware random number generators is currently limited to
devices that never fail. If the hardware is registered as a source for
random numbers it has to work. This prevents the use of i/o based
random number devices where the i/o might fail.

Add a check for errors after the read from a hardware random number device.

This patch is required to support large random numbers retrieved
from the CEX2C cards on System z.
Signed-off-by: NRalph Wuerthner <rwuerthn@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>

Make it possible to unregister a Hardware Random Number Generator
device object in a safe way during a suspend/resume cycle.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Acked-by: NMichael Buesch <mb@bu3sch.de>
Cc: Michael Buesch <mb@bu3sch.de>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "John W. Linville" <linville@tuxdriver.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Len Brown <lenb@kernel.org>
Cc: Greg KH <greg@kroah.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Handle waiting for new random within the drivers themselves, this allows to
use better suited timeouts for the individual rngs.
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Acked-by: NMichael Buesch <mb@bu3sch.de>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

This also ment that some of the misc drivers had to also be fixed
up as they were assuming the device was a class_device.
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

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: NArjan van de Ven <arjan@linux.intel.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NMichael Buesch <mb@bu3sch.de>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>