The kvm_arch_vcpu_load() does not validate whether the floating-point
control (FPC) is valid.  Further, the return code of the restore is not
checked too.  If the FPC is invalid, the restore fails and the host FPC
value might remain.  The correct behavior would be to clear the FPC if it
is not valid.  Hence, validate the FPC value and, optionally, reset the
value before restoring it.
Reviewed-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: NHendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Let's remove "kvm-s390" from our printk messages and make use
of pr_fmt instead.

Also replace one printk() occurrence by a equivalent pr_warn
on the way.
Suggested-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

Thinking about it, I can't find a real use case where we want
to block a VCPU and not kick it out of SIE. (except if we want
to do the same in batch for multiple VCPUs - but that's a micro
optimization)

So let's simply perform the exit_sie() calls directly when setting
the other magic block bits in the SIE.

Otherwise e.g. kvm_s390_set_tod_low() still has other VCPUs running
after that call, working with a wrong epoch.

Fixes: 27406cd5 ("KVM: s390: provide functions for blocking all CPUs")
Acked-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

This lets the function access the new memory slot without going through
kvm_memslots and id_to_memslot.  It will simplify the code when more
than one address space will be supported.

Unfortunately, the "const"ness of the new argument must be casted
away in two places.  Fixing KVM to accept const struct kvm_memory_slot
pointers would require modifications in pretty much all architectures,
and is left for later.
Reviewed-by: NRadim Krcmar <rkrcmar@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Architecture-specific helpers are not supposed to muck with
struct kvm_userspace_memory_region contents.  Add const to
enforce this.

In order to eliminate the only write in __kvm_set_memory_region,
the cleaning of deleted slots is pulled up from update_memslots
to __kvm_set_memory_region.
Reviewed-by: NTakuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Reviewed-by: NRadim Krcmar <rkrcmar@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

kvm_memslots provides lockdep checking.  Use it consistently instead of
explicit dereferencing of kvm->memslots.
Reviewed-by: NRadim Krcmar <rkrcmar@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Let's unify basic access to sclp fields by storing the data in an external
struct in asm/sclp.h.

The values can now directly be accessed by other components, so there is
no need for most accessor functions and external variables anymore.

The mtid, mtid_max and facility part will be cleaned up separately.
Acked-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Some updates to the control blocks need to be done in a way that
ensures that no CPU is within SIE. Provide wrappers around the
s390_vcpu_block functions and adopt the TOD migration code to
update in a guaranteed fashion. Also rename these functions to
have the kvm_s390_ prefix as everything else.
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>

exit_sie_sync is used to kick CPUs out of SIE and prevent reentering at
any point in time. This is used to reload the prefix pages and to
set the IBS stuff in a way that guarantees that after this function
returns we are no longer in SIE. All current users trigger KVM requests.

The request must be set before we block the CPUs to avoid races. Let's
make this implicit by adding the request into a new function
kvm_s390_sync_requests that replaces exit_sie_sync and split out
s390_vcpu_block and s390_vcpu_unblock, that can be used to keep
CPUs out of SIE independent of requests.
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: NCornelia Huck <cornelia.huck@de.ibm.com>

1. Enable EDAT2 in the list of KVM facilities

2. Handle 2G frames in pfmf instruction
If we support EDAT2, we may enable handling of 2G frames if not in 24
bit mode.

3. Enable EDAT2 in sie_block
If the EDAT2 facility is available we enable GED2 mode control in the
sie_block.
Reviewed-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NGuenther Hutzl <hutzl@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

We should only enable EDAT1 for the guest if the host actually supports
it and the cpu model for the guest has EDAT-1 enabled.
Reviewed-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NGuenther Hutzl <hutzl@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

The fast path for a sie exit is that no kvm reqest is pending.
Make an early check to skip all single bit checks.
Reviewed-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

Several kvm architectures disable interrupts before kvm_guest_enter.
kvm_guest_enter then uses local_irq_save/restore to disable interrupts
again or for the first time. Lets provide underscore versions of
kvm_guest_{enter|exit} that assume being called locked.
kvm_guest_enter now disables interrupts for the full function and
thus we can remove the check for preemptible.

This patch then adopts s390/kvm to use local_irq_disable/enable calls
which are slighty cheaper that local_irq_save/restore and call these
new functions.
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

commit b273921356df ("KVM: s390: enable more features that need
no hypervisor changes") also enabled RRBM. Turns out that this
instruction does need some KVM code, so lets disable that bit
again.
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Fixes: b273921356df ("KVM: s390: enable more features that need no hypervisor changes")
Message-Id: <1429093624-49611-2-git-send-email-borntraeger@de.ibm.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This patch adds support to migrate vcpu interrupts. Two new vcpu ioctls
are added which get/set the complete status of pending interrupts in one
go. The ioctls are marked as available with the new capability
KVM_CAP_S390_IRQ_STATE.

We can not use a ONEREG, as the number of pending local interrupts is not
constant and depends on the number of CPUs.

To retrieve the interrupt state we add an ioctl KVM_S390_GET_IRQ_STATE.
Its input parameter is a pointer to a struct kvm_s390_irq_state which
has a buffer and length.  For all currently pending interrupts, we copy
a struct kvm_s390_irq into the buffer and pass it to userspace.

To store interrupt state into a buffer provided by userspace, we add an
ioctl KVM_S390_SET_IRQ_STATE. It passes a struct kvm_s390_irq_state into
the kernel and injects all interrupts contained in the buffer.
Signed-off-by: NJens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Acked-by: NCornelia Huck <cornelia.huck@de.ibm.com>

We have introduced struct kvm_s390_irq a while ago which allows to
inject all kinds of interrupts as defined in the Principles of
Operation.
Add ioctl to inject interrupts with the extended struct kvm_s390_irq
Signed-off-by: NJens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Acked-by: NCornelia Huck <cornelia.huck@de.ibm.com>

This patch makes interrupt handling compliant to the z/Architecture
Principles of Operation with regard to interrupt priorities.

Add a bitmap for pending floating interrupts. Each bit relates to a
interrupt type and its list. A turned on bit indicates that a list
contains items (interrupts) which need to be delivered.  When delivering
interrupts on a cpu we can merge the existing bitmap for cpu-local
interrupts and floating interrupts and have a single mechanism for
delivery.
Currently we have one list for all kinds of floating interrupts and a
corresponding spin lock. This patch adds a separate list per
interrupt type. An exception to this are service signal and machine check
interrupts, as there can be only one pending interrupt at a time.
Signed-off-by: NJens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Acked-by: NCornelia Huck <cornelia.huck@de.ibm.com>

After some review about what these facilities do, the following
facilities will work under KVM and can, therefore, be reported
to the guest if the cpu model and the host cpu provide this bit.

There are plans underway to make the whole bit thing more readable,
but its not yet finished. So here are some last bit changes and
we enhance the KVM mask with:

9 The sense-running-status facility is installed in the
  z/Architecture architectural mode.
  ---> handled by SIE or KVM

10 The conditional-SSKE facility is installed in the
   z/Architecture architectural mode.
  ---> handled by SIE. KVM will retry SIE

13 The IPTE-range facility is installed in the
   z/Architecture architectural mode.
  ---> handled by SIE. KVM will retry SIE

36 The enhanced-monitor facility is installed in the
   z/Architecture architectural mode.
  ---> handled by SIE

47 The CMPSC-enhancement facility is installed in the
   z/Architecture architectural mode.
  ---> handled by SIE

48 The decimal-floating-point zoned-conversion facility
   is installed in the z/Architecture architectural mode.
  ---> handled by SIE

49 The execution-hint, load-and-trap, miscellaneous-
   instruction-extensions and processor-assist
  ---> handled by SIE

51 The local-TLB-clearing facility is installed in the
   z/Architecture architectural mode.
  ---> handled by SIE

52 The interlocked-access facility 2 is installed.
  ---> handled by SIE

53 The load/store-on-condition facility 2 and load-and-
   zero-rightmost-byte facility are installed in the
   z/Architecture architectural mode.
  ---> handled by SIE

57 The message-security-assist-extension-5 facility is
  installed in the z/Architecture architectural mode.
  ---> handled by SIE

66 The reset-reference-bits-multiple facility is installed
  in the z/Architecture architectural mode.
  ---> handled by SIE. KVM will retry SIE

80 The decimal-floating-point packed-conversion
   facility is installed in the z/Architecture architectural
   mode.
  ---> handled by SIE
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Tested-by: NMichael Mueller <mimu@linux.vnet.ibm.com>
Acked-by: NCornelia Huck <cornelia.huck@de.ibm.com>

The patch represents capability KVM_CAP_S390_VECTOR_REGISTERS by means
of the SIMD facility bit. This allows to a) disable the use of SIMD when
used in conjunction with a not-SIMD-aware QEMU, b) to enable SIMD when
used with a SIMD-aware version of QEMU and c) finally by means of a QEMU
version using the future cpu model ioctls.
Signed-off-by: NMichael Mueller <mimu@linux.vnet.ibm.com>
Reviewed-by: NEric Farman <farman@linux.vnet.ibm.com>
Tested-by: NEric Farman <farman@linux.vnet.ibm.com>
Reviewed-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

Setting the SIMD bit in the KVM mask is an issue because it makes the
facility visible but not usable to the guest, thus it needs to be
removed again.
Signed-off-by: NMichael Mueller <mimu@linux.vnet.ibm.com>
Reviewed-by: NEric Farman <farman@linux.vnet.ibm.com>
Reviewed-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

Provide the KVM_S390_GET_SKEYS and KVM_S390_SET_SKEYS ioctl which can be used
to get/set guest storage keys. This functionality is needed for live migration
of s390 guests that use storage keys.
Signed-off-by: NJason J. Herne <jjherne@linux.vnet.ibm.com>
Reviewed-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

The Store System Information (STSI) instruction currently collects all
information it relays to the caller in the kernel. Some information,
however, is only available in user space. An example of this is the
guest name: The kernel always sets "KVMGuest", but user space knows the
actual guest name.

This patch introduces a new exit, KVM_EXIT_S390_STSI, guarded by a
capability that can be enabled by user space if it wants to be able to
insert such data. User space will be provided with the target buffer
and the requested STSI function code.
Reviewed-by: NEric Farman <farman@linux.vnet.ibm.com>
Reviewed-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NEkaterina Tumanova <tumanova@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

On s390, we've got to make sure to hold the IPTE lock while accessing
logical memory. So let's add an ioctl for reading and writing logical
memory to provide this feature for userspace, too.
The maximum transfer size of this call is limited to 64kB to prevent
that the guest can trigger huge copy_from/to_user transfers. QEMU
currently only requests up to one or two pages so far, so 16*4kB seems
to be a reasonable limit here.
Signed-off-by: NThomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

In access register mode, the write_guest() read_guest() and other
functions will invoke the access register translation, which
requires an ar, designated by one of the instruction fields.
Signed-off-by: NAlexander Yarygin <yarygin@linux.vnet.ibm.com>
Reviewed-by: NThomas Huth <thuth@linux.vnet.ibm.com>
Acked-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

As all cleanup functions can handle their respective NULL case
there is no need to have more than one error jump label.
Signed-off-by: NDominik Dingel <dingel@linux.vnet.ibm.com>
Acked-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

POWER supports irqfds but forgot to advertise them.  Some userspace does
not check for the capability, but others check it---thus they work on
x86 and s390 but not POWER.

To avoid that other architectures in the future make the same mistake, let
common code handle KVM_CAP_IRQFD the same way as KVM_CAP_IRQFD_RESAMPLE.
Reported-and-tested-by: NGreg Kurz <gkurz@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org
Fixes: 297e2105Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

We finally have all the pieces in place, so let's include the
vector facility bit in the mask of available hardware facilities
for the guest to recognize.  Also, enable the vector functionality
in the guest control blocks, to avoid a possible vector data
exception that would otherwise occur when a vector instruction
is issued by the guest operating system.
Signed-off-by: NEric Farman <farman@linux.vnet.ibm.com>
Reviewed-by: NThomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

Store additional status in the machine check handler, in order to
collect status (such as vector registers) that is not defined by
store status.
Signed-off-by: NEric Farman <farman@linux.vnet.ibm.com>
Reviewed-by: NThomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

The new SIGP order Store Additional Status at Address is totally
handled by user space, but we should still record the occurrence
of this order in the kernel code.
Signed-off-by: NEric Farman <farman@linux.vnet.ibm.com>
Reviewed-by: NThomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

Define and allocate space for both the host and guest views of
the vector registers for a given vcpu.  The 32 vector registers
occupy 128 bits each (512 bytes total), but architecturally are
paired with 512 additional bytes of reserved space for future
expansion.

The kvm_sync_regs structs containing the registers are union'ed
with 1024 bytes of padding in the common kvm_run struct.  The
addition of 1024 bytes of new register information clearly exceeds
the existing union, so an expansion of that padding is required.

When changing environments, we need to appropriately save and
restore the vector registers viewed by both the host and guest,
into and out of the sync_regs space.

The floating point registers overlay the upper half of vector
registers 0-15, so there's a bit of data duplication here that
needs to be carefully avoided.
Signed-off-by: NEric Farman <farman@linux.vnet.ibm.com>
Reviewed-by: NThomas Huth <thuth@linux.vnet.ibm.com>
Acked-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

The function kvm_s390_vcpu_setup_model() now performs all cpu model realated
setup tasks for a vcpu. Besides cpuid and ibc initialization, facility list
assignment takes place during the setup step as well. The model setup has been
pulled to the begin of vcpu setup to allow kvm facility tests.

There is no need to protect the cpu model setup with a lock since the attributes
can't be changed anymore as soon the first vcpu is online.
Signed-off-by: NMichael Mueller <mimu@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

When the SIE exited by a DAT access exceptions which we can not
resolve, the guest tried to access a page which is out of bounds
and can not be paged-in. In this case we have to signal the bad
access by injecting an address exception. However, address exceptions
are either suppressing or terminating, i.e. the PSW has to point to
the next instruction when the exception is delivered. Since the
originating DAT access exception is nullifying, the PSW still
points to the offending instruction instead, so we've got to forward
the PSW to the next instruction.
Having fixed this issue, we can now also enable the TPROT
interpretation facility again which had been disabled because
of this problem.
Signed-off-by: NThomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

With patch "include guest facilities in kvm facility test" it is no
longer necessary to have special handling for the non-LPAR case.
Signed-off-by: NMichael Mueller <mimu@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

Most facility related decisions in KVM have to take into account:

- the facilities offered by the underlying run container (LPAR/VM)
- the facilities supported by the KVM code itself
- the facilities requested by a guest VM

This patch adds the KVM driver requested facilities to the test routine.

It additionally renames struct s390_model_fac to kvm_s390_fac and its field
names to be more meaningful.

The semantics of the facilities stored in the KVM architecture structure
is changed. The address arch.model.fac->list now points to the guest
facility list and arch.model.fac->mask points to the KVM facility mask.

This patch fixes the behaviour of KVM for some facilities for guests
that ignore the guest visible facility bits, e.g. guests could use
transactional memory intructions on hosts supporting them even if the
chosen cpu model would not offer them.

The userspace interface is not affected by this change.
Signed-off-by: NMichael Mueller <mimu@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

The facility lists were not fully copied.
Signed-off-by: NMichael Mueller <mimu@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

Under z/VM PQAP might trigger an operation exception if no crypto cards
are defined via APVIRTUAL or APDEDICATED.

[  386.098666] Kernel BUG at 0000000000135c56 [verbose debug info unavailable]
[  386.098693] illegal operation: 0001 ilc:2 [#1] SMP
[...]
[  386.098751] Krnl PSW : 0704c00180000000 0000000000135c56 (kvm_s390_apxa_installed+0x46/0x98)
[...]
[  386.098804]  [<000000000013627c>] kvm_arch_init_vm+0x29c/0x358
[  386.098806]  [<000000000012d008>] kvm_dev_ioctl+0xc0/0x460
[  386.098809]  [<00000000002c639a>] do_vfs_ioctl+0x332/0x508
[  386.098811]  [<00000000002c660e>] SyS_ioctl+0x9e/0xb0
[  386.098814]  [<000000000070476a>] system_call+0xd6/0x258
[  386.098815]  [<000003fffc7400a2>] 0x3fffc7400a2

Lets add an extable entry and provide a zeroed config in that case.
Reported-by: NStefan Zimmermann <stzi@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: NThomas Huth <thuth@linux.vnet.ibm.com>
Tested-by: NStefan Zimmermann <stzi@linux.vnet.ibm.com>

z/VM and LPAR enable key wrapping by default, lets do the same on KVM.
Signed-off-by: NTony Krowiak <akrowiak@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

This patch enables cpu model support in kvm/s390 via the vm attribute
interface.

During KVM initialization, the host properties cpuid, IBC value and the
facility list are stored in the architecture specific cpu model structure.

During vcpu setup, these properties are taken to initialize the related SIE
state. This mechanism allows to adjust the properties from user space and thus
to implement different selectable cpu models.

This patch uses the IBC functionality to block instructions that have not
been implemented at the requested CPU type and GA level compared to the
full host capability.

Userspace has to initialize the cpu model before vcpu creation. A cpu model
change of running vcpus is not possible.
Signed-off-by: NMichael Mueller <mimu@linux.vnet.ibm.com>
Reviewed-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

The patch introduces facilities and cpu_ids per virtual machine.
Different virtual machines may want to expose different facilities and
cpu ids to the guest, so let's make them per-vm instead of global.
Signed-off-by: NMichael Mueller <mimu@linux.vnet.ibm.com>
Reviewed-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

We need to specify a different format for the crypto control block
depending on whether the APXA facility is installed or not. Let's
test for it by executing the PQAP(QCI) function and use either a
format-1 or a format-2 crypto control block accordingly. This is a
host only change for z13 and does not affect the guest view.
Signed-off-by: NTony Krowiak <akrowiak@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>