Remove any data that we might have in a port's inbuf when closing a port
or when any data is received when a port is closed.
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

The host can set a name for ports so that they're easily discoverable
instead of going by the /dev/vportNpn naming. This attribute will be
placed in /sys/class/virtio-ports/vportNpn/name. udev scripts can then
create symlinks to the port using the name.
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Add a guest_connected field that ensures only one process
can have a port open at a time.

This also ensures we don't have a race when we later add support for
dropping buffers when closing the char dev and buffer caching is turned
off for the particular port.
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Allow guest userspace applications to open, read from, write to, poll
the ports via the char dev interface.

When a port gets opened, a notification is sent to the host via a
control message indicating a connection has been established. Similarly,
on closing of the port, a notification is sent indicating disconnection.
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

The char device will be used as an interface by applications on the
guest to communicate with apps on the host.

The devices created are placed in /dev/vportNpn where N is the
virtio-console device number and n is the port number for that device.

One dynamic major device number is allocated for each device and minor
numbers are allocated for the ports contained within that device.

The file operation for the char devs will be added in the following
commits.
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

When ports get advertised as char devices, the buffers will come from
userspace. Equip the fill_readbuf function with the ability to write
to userspace buffers.
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

This commit adds a new feature, MULTIPORT. If the host supports this
feature as well, the config space has the number of ports defined for
that device. New ports are spawned according to this information.

The config space also has the maximum number of ports that can be
spawned for a particular device. This is useful in initializing the
appropriate number of virtqueues in advance, as ports might be
hot-plugged in later.

Using this feature, generic ports can be created which are not tied to
hvc consoles.

We also open up a private channel between the host and the guest via
which some "control" messages are exchanged for the ports, like whether
the port being spawned is a console port, resizing the console window,
etc.

Next commits will add support for hotplugging and presenting char
devices in /dev/ for bi-directional guest-host communication.
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Adding support for generic ports that will write to userspace will need
some code changes.

Consolidate the write routine into send_buf() and put_chars() now just
calls into the new function.
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

In preparation for serving data to userspace (generic ports) as well as
in-kernel users (hvc consoles), separate out the functionality common to
both in a 'fill_readbuf()' function.
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

With support for multiple ports, each port will have its own input and
output vqs. Prepare the probe function for this change.
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Console ports could be hot-added. Also, with the new multiport support,
a port is identified as a console port only if the host sends a control
message.

Move the console port init into a separate function so it can be invoked
from other places.
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Move out console-specific stuff into a separate struct from 'struct
port' as we need to maintain two lists: one for all the ports (which
includes consoles) and one only for consoles since the hvc callbacks
only give us the vtermno.

This makes console handling cleaner.
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

When multiple console support is added, ensure each port's size gets
updated when a new one is opened via hvc.
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Rather than assume a single port, add a 'struct ports_device' which
stores data related to all the ports for that device.

Currently, there's only one port and is hooked up with hvc, but that
will change.
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Now we can use an allocation function to remove our global console variable.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Keep a list of all ports being used as a console, and provide a lock
and a lookup function.  The hvc callbacks only give us a vterm number,
so we need to map this.
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Part of removing our "one console" assumptions, use vdev->priv to point
to the port (currently == the global console).
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

This makes taking locks around the get_buf vq operation easier, as well
as complements the add_inbuf() operation.
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

add_inbuf() assumed one port and one inbuf per port. Remove that
assumption.

Also move the function so that put_chars and get_chars are together.
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Collect port buffer, used_len, offset fields into a single structure.
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

We are heading towards a multiple-"port" system, so as part of weaning off
globals we encapsulate the information into 'struct port'.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

We support only one virtio_console device at a time. If multiple are
found, error out if one is already initialized.
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

This is nicer for modern R/O protection.  And noone needs it non-const, so
constify the callers as well.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
To: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: linuxppc-dev@ozlabs.org

That way, we can make it const as is good kernel style.  We use a separate
indirection for the early console, rather than mugging ops.put_chars.

We rename it hv_ops, too.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Remove old lguest-style comments.

[Amit: - wingify comments acc. to kernel style
       - indent comments ]
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

When suspending, tpm_infineon calls the generic suspend function of the
TPM framework.  However, the TPM framework does not return and the system
hangs upon suspend.  When sending the necessary command "TPM_SaveState"
directly within the driver, suspending and resuming works fine.
Signed-off-by: NMarcel Selhorst <m.selhorst@sirrix.com>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Debora Velarde <debora@linux.vnet.ibm.com>
Cc: Rajiv Andrade <srajiv@linux.vnet.ibm.com>
Cc: <stable@kernel.org>		[2.6.32.x]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This reverts commit 70362511 ("tty: fix race in tty_fasync") and
commit b04da8bf ("fnctl: f_modown should call write_lock_irqsave/
restore") that tried to fix up some of the fallout but was incomplete.

It turns out that we really cannot hold 'tty->ctrl_lock' over calling
__f_setown, because not only did that cause problems with interrupt
disables (which the second commit fixed), it also causes a potential
ABBA deadlock due to lock ordering.

Thanks to Tetsuo Handa for following up on the issue, and running
lockdep to show the problem.  It goes roughly like this:

 - f_getown gets filp->f_owner.lock for reading without interrupts
   disabled, so an interrupt that happens while that lock is held can
   cause a lockdep chain from f_owner.lock -> sighand->siglock.

 - at the same time, the tty->ctrl_lock -> f_owner.lock chain that
   commit 70362511 introduced, together with the pre-existing
   sighand->siglock -> tty->ctrl_lock chain means that we have a lock
   dependency the other way too.

So instead of extending tty->ctrl_lock over the whole __f_setown() call,
we now just take a reference to the 'pid' structure while holding the
lock, and then release it after having done the __f_setown.  That still
guarantees that 'struct pid' won't go away from under us, which is all
we really ever needed.
Reported-and-tested-by: NTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>
Acked-by: NAmérico Wang <xiyou.wangcong@gmail.com>
Cc: stable@kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This fixes the regression introduced by commit
42590a75 ("x86/agp: Fix
agp_amd64_init and agp_amd64_cleanup").

The commit 61684cea fixed the
above regression but it's not enough. When amd64-agp is built as
a module, AGP isn't initialized, iommu is initialized, all the
aperture is owned by the iommu.
Reported-by: NMarin Mitov <mitov@issp.bas.bg>
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Tested-by: NMarin Mitov <mitov@issp.bas.bg>
LKML-Reference: <20100204090802S.fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

write_kmem() used to assume vwrite() always return the full buffer length.
However now vwrite() could return 0 to indicate memory hole.  This
creates a bug that "buf" is not advanced accordingly.

Fix it to simply ignore the return value, hence the memory hole.
Signed-off-by: NWu Fengguang <fengguang.wu@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Tejun Heo <tj@kernel.org>
Cc: Nick Piggin <npiggin@suse.de>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Otherwise vmalloc_to_page() will BUG().

This also makes the kmem read/write implementation aligned with mem(4):
"References to nonexistent locations cause errors to be returned." Here we
return -ENXIO (inspired by Hugh) if no bytes have been transfered to/from
user space, otherwise return partial read/write results.
Signed-off-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: NWu Fengguang <fengguang.wu@intel.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The previous changeset left behind an unused inode variable.
This patch removes it.
Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

No other driver does anything remotely like this that I know of except
for the tty drivers, and I can't see any reason for random/urandom to do
it. In fact, it's a (trivial, harmless) timing information leak. And
obviously, it generates power- and flash-cycle wasting I/O, especially
if combined with something like hwrngd. Also, it breaks ubifs's
expectations.
Signed-off-by: NMatt Mackall <mpm@selenic.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

This fixes the regression introduced by commit
42590a75 ("x86/agp: Fix
agp_amd64_init and agp_amd64_cleanup").

The above commit changes agp_amd64_init() not to do anything if
gart_iommu_aperture is not zero.

If GART iommu calls agp_amd64_init(), we need to skip
agp_amd64_init() when it's called later via module_init.

The problem is that gart_iommu_init() calls agp_amd64_init()
with not zero gart_iommu_aperture so agp_amd64_init() is never
initialized.

When gart_iommu_init() calls agp_amd64_init(), agp should be
always initialized.
Reported-by: NMarin Mitov <mitov@issp.bas.bg>
Reported-by: NJohannes Hirte <johannes.hirte@fem.tu-ilmenau.de>
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Tested-by: NMarin Mitov <mitov@issp.bas.bg>
Tested-by: NKevin Winchester <kjwinchester@gmail.com>
Cc: davej@redhat.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference: <20100125141006O.fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

For SGI UV node controllers (HUB) rev 2.0 or greater, use
replicated cachelines to read the RTC timer.  This optimization
allows faster simulataneous reads from a given socket.
Signed-off-by: NDimitri Sivanich <sivanich@sgi.com>
Cc: Jack Steiner <steiner@sgi.com>
LKML-Reference: <20100122154140.GB4975@sgi.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

We need to keep the lock held over the call to __f_setown() to
prevent a PID race.

Thanks to Al Viro for pointing out the problem, and to Travis for
making us look here in the first place.

Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Tavis Ormandy <taviso@google.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Julien Tinnes <jln@google.com>
Cc: Matt Mackall <mpm@selenic.com>
Cc: stable <stable@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Nozomi goes wrong if you get the sequence

	open
	open
	close

	[stuff]
	close

which turns out to occur on some ppp type setups.

This is a quick patch up for the problem. It's not really fixing Nozomi
which completely fails to implement tty open/close semantics and all the
other needed stuff. Doing it right is a rather more invasive patch set and
not one that will backport.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Cc: stable <stable@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Fix fixes the following warnings by renaming the driver structures to be
suffixed with _driver.

WARNING: drivers/virtio/virtio_balloon.o(.data+0x88): Section mismatch in reference from the variable virtio_balloon to the function .devexit.text:virtballoon_remove()

WARNING: drivers/char/hw_random/virtio-rng.o(.data+0x88): Section mismatch in reference from the variable virtio_rng to the function .devexit.text:virtrng_remove()
Signed-off-by: NJeff Mahoney <jeffm@suse.com>
Acked-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This enables possible 36bit address mask on 965G that use physical
address for hw status page.
Signed-off-by: NZhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: NEric Anholt <eric@anholt.net>

Hi Stephen,

	next-20090925 randconfig build breaks on hvcs driver on powerpc,
with HVC_CONSOLE=n.

ERROR: ".hvc_put_chars" [drivers/char/hvcs.ko] undefined!
ERROR: ".hvc_get_chars" [drivers/char/hvcs.ko] undefined!

adding the dependency of HVC_CONSOLE helped
Signed-off-by: NKamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

This fixes the regression introduced by the commit
f405d2c0.

The above commit fixes the following issue:

  http://marc.info/?l=linux-kernel&m=126192729110083&w=2

However, it doesn't work properly when you remove and insert the
agp_amd64 module again.

agp_amd64_init() and agp_amd64_cleanup should be called only
when gart_iommu is not called earlier (that is, the GART IOMMU
is not enabled). We need to use 'gart_iommu_aperture' to see if
GART IOMMU is enabled or not.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: mitov@issp.bas.bg
Cc: davej@redhat.com
LKML-Reference: <20100104161603L.fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NIngo Molnar <mingo@elte.hu>