The code in the various ptep_xxx functions has grown quite large,
consolidate them to four out-of-line functions:
  ptep_xchg_direct to exchange a pte with another with immediate flushing
  ptep_xchg_lazy to exchange a pte with another in a batched update
  ptep_modify_prot_start to begin a protection flags update
  ptep_modify_prot_commit to commit a protection flags update
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Provide a user space interface to issue call logical-processor instructions.
Only selected CLP commands are allowed, enough to get the full overview of
the installed PCI functions.
Reviewed-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

git commit 26f15caa ("s390/cmpxchg: simplify cmpxchg_double")
removed support for cmpxchg_double for two consecutive four byte
values, for which it would generate a cds instruction.

However I forgot to remove the corresponding define in our percpu
header file, which means that this_cpu_cmpxchg_double would now
incorrectly generate a cdsg instruction if being used on a double four
byte location. Therefore remove the percpu define as well.

There is currently no user and therefore no bug fixed with
this. Obviously any such user could and should simply use cmpxchg.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

We have two close to identical report_user_fault functions.
Add a parameter to one and get rid of the other one in order
to reduce code duplication.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The comment describing the bit encoding for segment table entries
is incorrect in regard to the read and write bits. The segment
read bit is 0x0002 and write is 0x0001, not the other way around.
Reported-by: NGerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

We have four different stack tracers of which three had bugs. So it's
time to merge them to a single stack tracer which allows to specify a
call back function which will be called for each step.

This patch changes behavior a bit:

- the "nosched" and "in_sched_functions" check within
  save_stack_trace_tsk did work only for the last stack frame within a
  context. Now it considers the check for each stack frame like it
  should.

- both the oprofile variant and the perf_events variant did save a
  return address twice if a zero back chain was detected, which
  indicates an interrupt frame. The new dump_trace function will call
  the oprofile and perf_events backends with the psw address that is
  contained within the corresponding pt_regs structure instead.

- the original show_trace and save_context_stack functions did already
  use the psw address of the pt_regs structure if a zero back chain
  was detected. However now we ignore the psw address if it is a user
  space address. After all we trace the kernel stack and not the user
  space stack. This way we also get rid of the garbage user space
  address in case of warnings and / or panic call traces.

So this should make life easier since now there is only one stack
tracer left which we can break.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The first parameter of pgste_update_all is a pointer to a pte.
Simplify the code by passing the pte value.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Implement current_stack_pointer() helper function and use it
everywhere, instead of having several different inline assembly
variants.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Tested-by: NPeter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Acked-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

For each PCI function we need to maintain arch specific data in
struct zpci_dev which also contains a pointer to struct pci_dev.

When a function is registered or deregistered (which is triggered by PCI
common code) we need to adjust that pointer which could interfere with
the machine check handler (triggered by FW) using zpci_dev->pdev.

Since multiple instances of the same pdev could exist at a time this can't
be solved with locking.

Fix that by ditching the pdev pointer and use a bus walk to reach
struct pci_dev (only one instance of a pdev can be registered at the bus
at a time).
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: NGerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

git commit 904818e2
"s390/kernel: introduce fpu-internal.h with fpu helper functions"
introduced the fpregs_store / fp_regs_load helper. These function
fail to save and restore the floating pointer control registers.

The effect is that the FPC is not correctly handled on signal
delivery and signal return.

Cc: stable@vger.kernel.org # 4.4
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The kernel now always uses vector registers when available, however KVM
has special logic if support is really enabled for a guest. If support
is disabled, guest_fpregs.fregs will only contain memory for the fpu.
The kernel, however, will store vector registers into that area,
resulting in crazy memory overwrites.

Simply extending that area is not enough, because the format of the
registers also changes. We would have to do additional conversions, making
the code even more complex. Therefore let's directly use one place for
the vector/fpu registers + fpc (in kvm_run). We just have to convert the
data properly when accessing it. This makes current code much easier.

Please note that vector/fpu registers are now always stored to
vcpu->run->s.regs.vrs. Although this data is visible to QEMU and
used for migration, we only guarantee valid values to user space  when
KVM_SYNC_VRS is set. As that is only the case when we have vector
register support, we are on the safe side.

Fixes: b5510d9b ("s390/fpu: always enable the vector facility if it is available")
Cc: stable@vger.kernel.org # v4.4 d9a3a09a s390/kvm: remove dependency on struct save_area definition
Signed-off-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
[adopt to d9a3a09a]

Most of the constants defined in pci_io.h depend on each other
and thus can be calculated.
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: NGerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Provide and use a ZPCI_ADDR macro as the complement of ZPCI_IDX
to get rid of some constants in the code.
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: NGerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

ZPCI_IOMAP_MAX_ENTRIES is off by one. Let's adjust this
for the sake of correctness.
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: NGerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Move the generic implementation to <linux/dma-mapping.h> now that all
architectures support it and remove the HAVE_DMA_ATTR Kconfig symbol now
that everyone supports them.

[valentinrothberg@gmail.com: remove leftovers in Kconfig]
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Helge Deller <deller@gmx.de>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Steven Miao <realmz6@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NValentin Rothberg <valentinrothberg@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Yet another leftover from the 31 bit era. The usual operation
"y = x & PSW_ADDR_INSN" with the PSW_ADDR_INSN mask is a nop for
CONFIG_64BIT.

Therefore remove all usages and hope the code is a bit less confusing.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>

This is a leftover from the 31 bit area. For CONFIG_64BIT the usual
operation "y = x | PSW_ADDR_AMODE" is a nop. Therefore remove all
usages of PSW_ADDR_AMODE and make the code a bit less confusing.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>

The ssm instruction takes longer that stnsm/stosm as it is often
used to modify DAT and PER. We know that irqsave/irqrestore only
deals with external and I/O interrupts and we know that irqrestore
can transition only from disabled->disabled or disabled->enabled,
so we can use the faster stosm.
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

If anyone includes asm/livepatch.h when CONFIG_LIVEPATCH=n the build
fails with the existing error message. Change it to something saner.

[jkosina@suse.cz: fixed changelog typo spotted by Josh]
Suggested-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NMiroslav Benes <mbenes@suse.cz>
Acked-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

With new refcounting we don't need to mark PMDs splitting.  Let's drop
code to handle this.

pmdp_splitting_flush() is not needed too: on splitting PMD we will do
pmdp_clear_flush() + set_pte_at().  pmdp_clear_flush() will do IPI as
needed for fast_gup.
Signed-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Steve Capper <steve.capper@linaro.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

As per: lkml.kernel.org/r/20150921112252.3c2937e1@mschwide
atomics imply a barrier on s390, so s390 should change
smp_mb__before_atomic and smp_mb__after_atomic to barrier() instead of
smp_mb() and hence should not use the generic versions.
Suggested-by: NPeter Zijlstra <peterz@infradead.org>
Suggested-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Acked-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>

The s390 kernel is SMP to 99.99%, we just didn't bother with a
non-smp variant for the memory-barriers. If the generic header
is used we'd get the non-smp version for free. It will save a
small amount of text space for CONFIG_SMP=n.
Suggested-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>

This defines __smp_xxx barriers for s390,
for use by virtualization.

Some smp_xxx barriers are removed as they are
defined correctly by asm-generic/barriers.h

Note: smp_mb, smp_rmb and smp_wmb are defined as full barriers
unconditionally on this architecture.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>

On s390 read_barrier_depends, smp_read_barrier_depends
smp_store_mb(), smp_mb__before_atomic and smp_mb__after_atomic match the
asm-generic variants exactly. Drop the local definitions and pull in
asm-generic/barrier.h instead.

This is in preparation to refactoring this code area.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>

With commit b92b8b35 ("locking/arch: Rename set_mb() to smp_store_mb()")
it was made clear that the context of this call (and thus set_mb)
is strictly for CPU ordering, as opposed to IO. As such all archs
should use the smp variant of mb(), respecting the semantics and
saving a mandatory barrier on UP.
Signed-off-by: NDavidlohr Bueso <dbueso@suse.de>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: <linux-arch@vger.kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: dave@stgolabs.net
Link: http://lkml.kernel.org/r/1445975631-17047-3-git-send-email-dave@stgolabs.netSigned-off-by: NIngo Molnar <mingo@kernel.org>
Reviewed-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>

Add the CPU number to the per-cpu vdso data page and add the
__kernel_getcpu function to the vdso object to retrieve the
CPU number in user space.
Suggested-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Finally get rid of the leading underscore. I tried this already two or
three years ago, however Michael Holzheu objected since this would
break the crash utility (again).

However Michael integrated support for the new name into the crash
utility back then, so it doesn't break if the name will be changed
now.  So finally get rid of the ever confusing leading underscore.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The memory detection code historically had to use unsigned long long
since the machine reported the true memory size (>4GB) even if the
virtual machine was running in ESA/390 mode.

Since the old code is gone use unsigned long everywhere and also get
rid of an unused ADDR2G define.

(this patch converts all long longs within sclp_info to longs)

There are many more possible conversions, however that can be done if
somebody touches the corresponding code.  Since people started to
convert unrelated long types to long longs because of the types within
struct sclp_info convert this now.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The long longs were introduced by me in order to have a working
definition of the struct psw_bits also in 31 bit mode. Since that is
gone also get rid of the long longs.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Add missing multithreading fields of SYSIB 1.2.2 (Basic-Machine CPUs)
to the output of /proc/sysinfo.

Also use bitfields for SYSIB 2.2.2 to simplify the C code a bit.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Since the numbers now overlap, it makes sense to enumerate
them in asm/kvm_host.h rather than linux/kvm_host.h.  Functions
that refer to architecture-specific requests are also moved
to arch/.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This patch adds runtime instrumentation support for KVM guest. We need to
setup a save area for the runtime instrumentation-controls control block(RICCB)
and implement the necessary interfaces to live migrate the guest settings.

We setup the sie control block in a way, that the runtime
instrumentation instructions of a guest are handled by hardware.

We also add a capability KVM_CAP_S390_RI to make this feature opt-in as
it needs migration support.
Signed-off-by: NFan Zhang <zhangfan@linux.vnet.ibm.com>
Acked-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

Use CONFIG_TOPOLOGY which selects CONFIG_SCHED_* all over the place to
reduce the random usage of the previous config options.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Replace the current semi-arbitrary distribution of inline assemblies:
 - Inline assemblies used by CIO go into ioasm.h
 - Data definitions used by inline assemblies go into cio.h

Beyond cleaning up the current structure this is also required for
use of tracepoints in inline assemblies introduced by a follow-on
patch.
Signed-off-by: NPeter Oberparleiter <oberpar@linux.vnet.ibm.com>
Acked-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Acked-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Over time some machine flags got unused (e.g. MACHINE_FLAG_MVPG)
or are available on all 64bit systems (MACHINE_FLAG_CSP,
MACHINE_FLAG_IEEE) - let's remove them.
Reorder the other ones to match the order of the MACHINE_HAS_*
macros and renumber all bits to avoid holes.
Also fix the comment about where the flags are detected.
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

If configured for z13 assume the kernel makes use of the instructions
that are part of the load-and-zero-rightmost-byte facility and
load/store-on-condition facility 2.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

test_facility() can be optimized for bits which must be set anyway,
due to the check in head.S. This removes a couple of superfluous
runtime checks.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The facility lists contain a lot of bits which are not necessary to
run the kernel.  Therefore remove them and keep only those bits which
are required for the kernel.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Modifying the architecture level set facility lists was always very
error prone. Given the numbering of the facility bits within the
Principles of Operation, where the most significant bit number is 0,
it happened a lot of times that wrong bits were set or cleared.

Therefore this patch adds a tool "gen_facilities" which generates
include/generated/facilites.h.  The definition of the bits to be set
is contained within arch/s390/include/asm/facilities_src.h and can be
easily extended to e.g. also generate such lists for the KVM module.

The generated file looks like this:

 #define FACILITIES_ALS _AC(0xc1006450f0040000,UL)
 #define FACILITIES_ALS_DWORDS 1

The facility bits defined in this patch match 1:1 to the current masks
that can be found in head.S.

That is if the tool gets executed with -march=z990 then the generated
masks will equal the masks in head.S for CONFIG_MARCH_Z990.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>