Convert the synchronous size sense code to an interrupt driven
approach. This allows to set the device online even if the
terminal is not connected. With the new code views can be
registered without a connected terminal, the tty can be opened
as soon as the device is online. After the terminal has been
connected and the size has been determined the tty is resized
to match the device characteristics..
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Add a notifier to create / destroy the device nodes for the tty view
and the fullscreen view. Only device nodes for online devices are
created and the device names will follow the convention as outlined
in Documentation/devices.txt: 3270/tty<x> for the tty nodes,
3270/tub<x> for hte fullscreen nodes and 3270/tub for the fullscreen
control node.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Corrects the order of tasklet_init vs. the allocation of the
read request which has been broken by git commit 9d2ae233
"TTY: tty3270, move initialization to allocation".
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Reintroduce the tty3270_open function which has been removed by
git commit 20cda6f2 "TTY: tty3270, add tty install". Without
the open function in the tty_operations tty_open will return
-ENODEV and the 3270 tty will not work.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Partially revert ae289dc1 "s390/3215: fix tty close handling", since this
leads sometimes to hanging agetty processes and therefore systems that get
stuck while starting.

This was magically fixed (bisected) by a common code patch from Alan Cox:
36b3c070 "tty: Move the handling of the tty release logic", however it was
unrelated.

Since the removed code worked for a decade, nobody knows anymore why it was
in there in the first place and debugging the observed hang is non-trivial
(at least for me :) ), let's just re-add the removed code before we see
other side effects.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>

Now that irq sum accounting for /proc/stat's "intr" line works again we
have the oddity that the sum field (first field) contains only the sum
of the second (external irqs) and third field (I/O interrupts).
The reason for that is that these two fields are already sums of all other
fields. So if we would sum up everything we would count every interrupt
twice.
This is broken since the split interrupt accounting was merged two years
ago: 052ff461 "[S390] irq: have detailed
statistics for interrupt types".
To fix this remove the split interrupt fields from /proc/stat's "intr"
line again and only have them in /proc/interrupts.

This restores the old behaviour, seems to be the only sane fix and mimics
a behaviour from other architectures where /proc/interrupts also contains
more than /proc/stat's "intr" line does.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Add SCLP PCI configure/deconfigure and implement a PCI hotplug
controller (s390_pci_hpc). The hotplug controller creates a slot
for every PCI function in stand-by or configured state. The PCI
functions are named after the PCI function ID (fid). By writing to
the power attribute in /sys/bus/pci/slots/<fid>/power the PCI function
is moved to stand-by or configured state. If moved to the configured
state the device is automatically scanned by the s390 PCI layer.
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Move and rename init_storage_keys() to pageattr.c, so it can also be
used from the sclp memory hotplug code in order to initialize
storage keys.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

After commit "TTY: move tty buffers to tty_port", the tty buffers are
not freed in some drivers. This is because tty_port_destructor is not
called whenever a tty_port is freed. This was an assumption I counted
with but was unfortunately untrue. So fix the drivers to fulfil this
assumption.

To be sure, the TTY buffers (and later some stuff) are gone along with
the tty_port, we have to call tty_port_destroy at tear-down places.
This is mostly where the structure containing a tty_port is freed.
This patch does exactly that -- put tty_port_destroy at those places.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The 3215 console always has the RAW3215_FIXED flag set, which causes
raw3215_shutdown() not to wait for outstanding I/O requests if an attached
tty gets closed.
The flag however can be simply removed, so we can guarantee that all requests
belonging to the tty have been processed when the tty is closed.

However the tasklet that belongs to the 3215 device may be scheduled even if
there is no tty attached anymore, since we have a race between console and tty
processing.
Thefore unconditional tty_wakekup() in raw3215_wakeup() can cause the following
NULL pointer dereference:

3.465368 Unable to handle kernel pointer dereference at virtual kernel address (null)
3.465448 Oops: 0004 #1 SMP
3.465454 Modules linked in:
3.465459 CPU: 1 Not tainted 3.6.0 #1
3.465462 Process swapper/1 (pid: 0, task: 000000003ffa4428, ksp: 000000003ffb7ce0)
3.465466 Krnl PSW : 0404100180000000 0000000000162f86 (__wake_up+0x46/0xb8)
3.465480            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:0 CC:1 PM:0 EA:3
         Krnl GPRS: fffffffffffffffe 0000000000000000 0000000000000160 0000000000000001
3.465492            0000000000000001 0000000000000004 0000000000000004 000000000096b490
3.465499            0000000000000001 0000000000000100 0000000000000001 0000000000000001
3.465506            070000003fc87d60 0000000000000160 000000003fc87d68 000000003fc87d00
3.465526 Krnl Code: 0000000000162f76: e3c0f0a80004      lg      %r12,168(%r15)
                    0000000000162f7c: 58000370          l       %r0,880
                   #0000000000162f80: c007ffffffff00    xilf    %r0,4294967295
                   >0000000000162f86: ba102000          cs      %r1,%r0,0(%r2)
                    0000000000162f8a: 1211              ltr     %r1,%r1
                    0000000000162f8c: a774002f          brc     7,162fea
                    0000000000162f90: b904002d          lgr     %r2,%r13
                    0000000000162f94: b904003a          lgr     %r3,%r10
3.465597 Call Trace:
3.465599 (<0400000000000000> 0x400000000000000)
3.465602  <000000000048c77e> raw3215_wakeup+0x2e/0x40
3.465607  <0000000000134d66> tasklet_action+0x96/0x168
3.465612  <000000000013423c> __do_softirq+0xd8/0x21c
3.465615  <0000000000134678> irq_exit+0xa8/0xac
3.465617  <000000000046c232> do_IRQ+0x182/0x248
3.465621  <00000000005c8296> io_return+0x0/0x8
3.465625  <00000000005c7cac> vtime_stop_cpu+0x4c/0xb8
3.465629 (<0000000000194e06> tick_nohz_idle_enter+0x4e/0x74)
3.465633  <0000000000104760> cpu_idle+0x170/0x184
3.465636  <00000000005b5182> smp_start_secondary+0xd6/0xe0
3.465641  <00000000005c86be> restart_int_handler+0x56/0x6c
3.465643  <0000000000000000> 0x0
3.465645 Last Breaking-Event-Address:
3.465647  <0000000000403136> tty_wakeup+0x46/0x98
3.465652
3.465654 Kernel panic - not syncing: Fatal exception in interrupt
01: HCPGIR450W CP entered; disabled wait PSW 00020001 80000000 00000000 0010F63C

The easiest solution is simply to check if tty is NULL in the tasklet.
If it is NULL nothing is to do (no tty attached), otherwise tty_wakeup()
can be called, since we hold a reference to the tty.
This is not nice... but it is a small patch and it works.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Convert a nonnegative error return code to a negative one, as returned
elsewhere in the function.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
(
if@p1 (\(ret < 0\|ret != 0\))
 { ... return ret; }
|
ret@p1 = 0
)
... when != ret = e1
    when != &ret
*if(...)
{
  ... when != ret = e2
      when forall
 return ret;
}
// </smpl>
Signed-off-by: NPeter Senna Tschudin <peter.senna@gmail.com>
Signed-off-by: NGerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Fix this compile error:

In file included from drivers/s390/char/tape_core.c:29:0:
drivers/s390/char/tape_std.h:103:66: warning: ‘struct request’ declared inside parameter list [enabled by default]
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Changing the return value of vmlogrdr_open() to -EOPNOTSUPP if O_NONBLOCK
is specified shouldn't have any negative side effects.
Any existing user wouldn't specify that flag since it wouldn't work anyway.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The return value was only internally used, so it's ok to change.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

I was checking why this spinlock was never initialized, but it turns
out it's not used anywhere, so we can drop it.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

This has two outcomes:
* we give the TTY layer a tty_port
* we do not find the info structure every time open is called on that
  tty

In this case ->install is the only thing we want to do. We do not need
->open at all. See the tty->count > 1 check.

And since we take a reference in ->install, we need also ->cleanup to
drop the reference to a view.

Final note, see that we leave raw3270_find_view in place. It is
because views are removed even from module_exit.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Cc: linux-s390@vger.kernel.org
Acked-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This has two outcomes:
* we give the TTY layer a tty_port
* we do not find the info structure every time open is called on that
  tty
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Cc: linux-s390@vger.kernel.org
Acked-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

raw3215[line] is set in probe, but not unset in remove. This will lead
to random crashes if the device is removed and the corresponding tty
opened later. open would dereference freed memory.

So set raw3215[line] to NULL in remove to fix that.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Cc: linux-s390@vger.kernel.org
Acked-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

So now for those drivers that can use neither tty_port_install nor
tty_port_register_driver but still have tty_port available before
tty_register_driver we use newly added tty_port_link_device.

The rest of the drivers that still do not provide tty_struct <->
tty_port link will have to be converted to implement
tty->ops->install.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Acked-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This looks like it was a mistake not to create device nodes for these
drivers. Let us create them from now on.

It will be necessary to call tty_register_device some way, either by
tty_register_driver implicitly or to call tty_register_device proper.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Cc: netdev@vger.kernel.org
Cc: linux390@de.ibm.com
Cc: linux-s390@vger.kernel.org
Cc: linux-cris-kernel@axis.com
Acked-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

On module unload, in tty3270_exit, we forgot to free the tty driver.
Add there a call to put_tty_driver.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Cc: linux-s390@vger.kernel.org
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

If the last block of the HSA is read, EVSTATE_ALL_STORED is returned
by SCLP. Because of a missing break in the switch statement two trace
entries are written in this case: "all stored" and "part stored".

This patch adds the missing break and also adds a "fall through"
comment to improve the readability.
Signed-off-by: NMichael Holzheu <holzheu@linux.vnet.ibm.com>
Reported-by: NDavid A Gilbert <DavidAGilbert@uk.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Remove the file name from the comment at top of many files. In most
cases the file name was wrong anyway, so it's rather pointless.

Also unify the IBM copyright statement. We did have a lot of sightly
different statements and wanted to change them one after another
whenever a file gets touched. However that never happened. Instead
people start to take the old/"wrong" statements to use as a template
for new files.
So unify all of them in one go.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>

For processing under KVM it is required to detect
the actual SCLP console type in order to set it as
preferred console.
Signed-off-by: NHeinz Graalfs <graalfs@linux.vnet.ibm.com>
Acked-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: NPeter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

Let the driver core handle driver attribute creation and removal. This
will simplify the code and eliminates races between attribute
availability and userspace notification via uevents.
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Let the driver core handle device attribute creation and removal. This
will simplify the code and eliminates races between attribute
availability and userspace notification via uevents.
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Replace __s390x__ with CONFIG_64BIT in all places that are not exported
to userspace or guarded with #ifdef __KERNEL__.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Currently qemu/kvm on s390 uses a guest mapping that does not
allow the guest backing page table to be write-protected to
support older systems. On those older systems a host write
protection fault will be delivered to the guest.

Newer systems allow to write-protect the guest backing memory
and let the fault be delivered to the host, thus allowing COW.

Use a capability bit to tell qemu if that is possible.
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Acked-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

Add missing storage key initialization when memory comes online.
Didn't hurt until now, since the kernel always uses access key 0.

However for debugging purposes we sometimes use a different key
and it might be good if everything is properly initialized...
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Fix compile error caused by "TTY: con3215, use tty from tty_port":

 CC      drivers/s390/char/con3215.o
drivers/s390/char/con3215.c: In function 'raw3215_wakeup':
drivers/s390/char/con3215.c:339:16: error: 'struct raw3215_info' has no member named 'tty'
make[1]: *** [drivers/s390/char/con3215.o] Error 1
make: *** [drivers/s390/char/] Error 2

Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Obtain tty_struct only once in ISR and pass it down to
raw3215_next_io. Other than that, we just use the tty with raised
reference. And set it properly in open and close.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Cc: linux-s390@vger.kernel.org
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

And use flags from that. But first we have to get rid of duplicated
flag names. From now on, for the standard ones that are stored in
tty_port->flags, we use ASYNC_* ones.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Cc: linux-s390@vger.kernel.org
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch is used to fix a memory leak issue in s390/char/vmur.c.
A character device instance is allocated by cdev_alloc, the cdev_del
will not free that space if cdev_init is applied before.
Signed-off-by: NDennis Chen <dennis1.chen@amd.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

And use tty from that. This means, we convert most of the users to
accept tty_port instead. This is not racy and ensures the tty to be
properly refcounted.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Cc: linux-s390@vger.kernel.org
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

So that we do not need to access tp->tty there. It is going away.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Cc: linux-s390@vger.kernel.org
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Blah, do not assume that raw3270_view is at the beginning of tty3270.
Use proper types and container_of wherever needed.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Cc: linux-s390@vger.kernel.org
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Let us initialize all the tty3270's members at the place where the
structure is allocated.

It cleans up tty->ops->open a bit.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Cc: linux-s390@vger.kernel.org
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

80 bytes which are allocated in tty->ops->open and assigned to
tty->driver_data are never used. Remove that.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Cc: linux-s390@vger.kernel.org
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

tty_port will hold tty buffers in the future. So we need to have it
even here. The only needed member here is tty, so let us store it in
the structure now.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Cc: linux-s390@vger.kernel.org
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>