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>

If lgr has not been initialized, the lgr_info_log() function currently
crashes because 'lgr_page' is not allocated. To fix this 'lgr_page'
is allocated statically now.
Signed-off-by: NMichael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Just saves a couple of instructions.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Avoid padding in the middle and the end of the data structure by
moving nohz_delay member to the beginning.
Saves eight byte per cpu.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The s390 idle accounting code uses a sequence counter which gets used
when the per cpu idle statistics get updated and read.

One assumption on read access is that only when the sequence counter is
even and did not change while reading all values the result is valid.
On cpu hotplug however the per cpu data structure gets initialized via
a cpu hotplug notifier on CPU_ONLINE.
CPU_ONLINE however is too late, since the onlined cpu is already running
and might access the per cpu data. Worst case is that the data structure
gets initialized while an idle thread is updating its idle statistics.
This will result in an uneven sequence counter after an update.

As a result user space tools like top, which access /proc/stat in order
to get idle stats, will busy loop waiting for the sequence counter to
become even again, which will never happen until the queried cpu will
update its idle statistics again. And even then the sequence counter
will only have an even value for a couple of cpu cycles.

Fix this by moving the initialization of the per cpu idle statistics
to cpu_init(). I prefer that solution in favor of changing the
notifier to CPU_UP_PREPARE, which would be a different solution to
the problem.

Cc: stable@vger.kernel.org
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

With git commit 85fe4025 ("fs: do not
assign default i_ino in new_inode") the get_next_ino() function was
moved from the new_inode() to the different file system implementations.
Unfortunately hypfs has been overlooked by the author. With this
patch the get_next_ino() is added also to hypfs.
Signed-off-by: NMichael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>

Fix problem that was introduced with patch "s390/smp: make absolute
lowcore / cpu restart parameter". After that patch the "dumpreipl"
shutdown action does not work any more. To fix the problem we have
to assign "reipl_block_actual" instead of "&reipl_block_actual"
Signed-off-by: NMichael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Setting the cpu restart parameters is done in three different fashions:
- directly setting the four parameters individually
- copying the four parameters with memcpy (using 4 * sizeof(long))
- copying the four parameters using a private structure

In addition code in entry*.S relies on a certain order of the restart
members of struct _lowcore.

Make all of this more robust to future changes by adding a
mem_absolute_assign(dest, val) define, which assigns val to dest
using absolute addressing mode. Also the load multiple instructions
in entry*.S have been split into separate load instruction so the
order of the struct _lowcore members doesn't matter anymore.

In addition move the prototypes of memcpy_real/absolute from uaccess.h
to processor.h. These memcpy* variants are not related to uaccess at all.
string.h doesn't seem to match as well, so lets use processor.h.

Also replace the eight byte array in struct _lowcore which represents a
misaliged u64 with a u64. The compiler will always create code that
handles the misaligned u64 correctly.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The creator_id is no longer used. Just get rid of it.
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Use sigp order code defines in assembly code as well.
With this change all places that use sigp constants should
have been converted to use self describing defines instead
of directly using constants.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

We got them from the kvm code, so let's use them.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The smp and the kvm code have different defines for the sigp order codes.
Let's just have a single place where these are defined.
Also move the sigp condition code and sigp cpu status bits to the new
sigp.h header file.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

condition code "status stored" for sigp sense running always implies
that only the "not running" status bit is set. Therefore no need to
check if it is set.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

After
commit 5e8010cb
    s390: replace TIF_SIE with PF_VCPU
there is no need to load the thread info before sie_loop where
it is also loaded.
Get rid of this duplicate instruction.
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Does block_sigmask() + tracehook_signal_handler();  called when
sigframe has been successfully built.  All architectures converted
to it; block_sigmask() itself is gone now (merged into this one).

I'm still not too happy with the signature, but that's a separate
story (IMO we need a structure that would contain signal number +
siginfo + k_sigaction, so that get_signal_to_deliver() would fill one,
signal_delivered(), handle_signal() and probably setup...frame() -
take one).
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Only 3 out of 63 do not.  Renamed the current variant to __set_current_blocked(),
added set_current_blocked() that will exclude unblockable signals, switched
open-coded instances to it.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

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

replace boilerplate "should we use ->saved_sigmask or ->blocked?"
with calls of obvious inlined helper...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

first fruits of ..._restore_sigmask() helpers: now we can take
boilerplate "signal didn't have a handler, clear RESTORE_SIGMASK
and restore the blocked mask from ->saved_mask" into a common
helper.  Open-coded instances switched...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

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

On s390 access_ok is a macro which discards all parameters and always
returns 1. This can result in compile warnings which warn about unused
variables like this:

fs/read_write.c: In function 'rw_copy_check_uvector':
fs/read_write.c:684:16: warning: unused variable 'buf' [-Wunused-variable]

Fix this by adding a __range_ok() function which consumes all parameters
but still always returns 1.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Now that hopefully all cmpxchg/xchg bugs have been fixed select
HAVE_CMPXCHG_LOCAL option which uncovered a couple of bugs on s390.

The only call site which is affected seems to be within mm/vmstat.c.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

For 1 and 2 byte operands for xchg and cmpxchg the old and new values
get or'ed into the larger 4 byte old value before the compare and swap
instruction gets executed. This is done without using the proper byte
mask before or'ing the values.
If the caller passed in negative old or new values these got sign
extended by the caller. Which in turn means that either the old value
never matches, or, even worse, unrelated bytes would be changed in memory.

Luckily there don't seem to be any callers around yet, since that would
have resulted in the specification exception fixed in an earlies patch.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

When accessing a 1 or 2 byte memory operand we cannot use the
passed address since the compare and swap instruction only works
for 4 byte aligned memory operands.
Hence we calculate an aligned address so that compare and swap works
correctly. However we don't pass the calculated address to the inline
assembly. This results in incorrect memory accesses and in a
specification exception if used on non 4 byte aligned memory operands.

Since this didn't happen until now, there don't seem to be
too many users of cmpxchg on unaligned addresses.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The cmpxchg macros and functions are a bit different than on other
architectures. In particular the macros do not store the return
value of a __cmpxchg function call in a variable before returning the
value.

This causes compile warnings that only occur on s390 like this one:

net/ipv4/af_inet.c: In function 'build_ehash_secret':
net/ipv4/af_inet.c:241:2: warning: value computed is not used [-Wunused-value]

To get rid of these warnings use the same construct that we already use
for the xchg macro, which was introduced for the same reason.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

All cmpxchg functions imply a memory barrier.
cmpxch64 did not have one for 31 bit code, so add it.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

It has been a big mistage to add the capabilities attribute to the
cpus in sysfs:
First the attribute only contains the cpu capability of primary cpus,
which however is not necessarily (or better: unlikely) the type of
cpu the kernel runs on, which is typically an IFL.
In addition all information that is necessary is available in
/proc/sysinfo already. So this attribute partially duplicated
informations.
So programs should look into the sysinfo file to retrieve all
informations they are interested in.

Since with this kernel release also the powersavings cpu attributes
are removed this seems to be a good opportunity to remove another
broken interface.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

If the IPL CPU is offline, currently the pcpu_delegate() function
used by smp_call_ipl_cpu() does not work because pcpu_delegate()
modifies the lowcore of the target CPU. In case of an offline
IPL CPU currently the prefix register is zero but pcpu->lowcore
still points to the old prefix page. Therefore the lowcore changes
done by pcpu_delegate() have no effect.

With this fix pcpu_delegate() now uses memcpy_absolute() and therefore
also prepares the absolute zero lowcore if the target CPU has prefix
register zero.
Signed-off-by: NMichael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

This patch introduces the new function memcpy_absolute() that allows to
copy memory using absolute addressing. This means that the prefix swap
does not apply when this function is used.

With this patch also all s390 kernel code that accesses absolute zero
now uses the new memcpy_absolute() function. The old and less generic
copy_to_absolute_zero() function is removed.
Signed-off-by: NMichael Holzheu <holzheu@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>

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

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

CPU-measurement alerts are generated for different CPU-measurement
facilities, for example, the sampling and counter facilities.
Split the irq stats according to available facilities.
Signed-off-by: NHendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The early_pgm_check_handler() function is also used after the
init phase in s390_reset_system(). Therefore it must not be in
the init section.
Signed-off-by: NMichael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Currently the PSW restart handler and kexec are executed in real
mode with DAT=off. For kexec/kdump the function setup_regs() is
called that uses the per-cpu variable "crash_notes". Because
there are situations when the per-cpu implementation uses vmalloc
memory, calling setup_regs() in real mode can cause a program
check interrupt.

To fix that problem this patch changes the following:

* Ensure that diag308_reset() does not change PSW bits to real mode
* Enable DAT in __do_restart() after we switched to an online CPU
* Enable DAT in __machine_kexec() after we switched to the IPL CPU
* Call setup_regs() before we switch to real mode and call purgatory
Reviewed-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NMichael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The crashkernel size for kdump can be reduced at runtime with the
sysfs file "/sys/kernel/kexec_crash_size". Currently those changes
do not update the OS info crashkernel information that is used
for stand-alone kdump. With this fix now also the OS info crashkernel
information is updated correctly.
Signed-off-by: NMichael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Because of a design change for stand-alone kdump the function that
was done by the OS info init function is moved to the boot loader
code. This has two implications that are implemented by this patch:
a) The OS info init function is no longer called by the kernel
b) The diag 308 subcode 1 reset is no longer done by the kdump boot code.
   This is necessary because otherwise the operation that is done now
   by the boot loader would be reversed. For the normal kexec based
   kdump mechansim the reset is already done by the kdump trigger code
   (e.g. panic or PSW restart).
Signed-off-by: NMichael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

guts of saved_sigmask-based sigsuspend/rt_sigsuspend.  Takes
kernel sigset_t *.

Open-coded instances replaced with calling it.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Sigh, I missed to check which architecture Kconfig files actually
include the core Kconfig file. There are a few which did not. So we
broke them.

Instead of adding the includes to those, we are better off to move the
include to init/Kconfig like we did already with irqs and others.

This does not change anything for the architectures using the old
style periodic timer mode. It just solves the build wreckage there.

For those architectures which use the clock events infrastructure it
moves the include of the core Kconfig file to "General setup" which is
a way more logical place than having it at random locations specified
by the architecture specific Kconfigs.
Reported-by: NIngo Molnar <mingo@kernel.org>
Cc: Anna-Maria Gleixner <anna-maria@glx-um.de>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Signed-off-by: NAnna-Maria Gleixner <anna-maria@glx-um.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Link: http://lkml.kernel.org/r/20120518163106.595607369@glx-um.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>