Commit graph

143 commits

Author SHA1 Message Date
Eugene (jno) Dvurechenski
5e04431523 KVM: s390: Introduce switching code
This patch adds code that performs transparent switch to Extended
SCA on addition of 65th VCPU in a VM. Disposal of ESCA is added too.
The entier ESCA functionality, however, is still not enabled.
The enablement will be provided in a separate patch.

This patch also uses read/write lock protection of SCA and its subfields for
possible disposal at the BSCA-to-ESCA transition. While only Basic SCA needs such
a protection (for the swap), any SCA access is now guarded.

Signed-off-by: Eugene (jno) Dvurechenski <jno@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-11-30 12:47:08 +01:00
Eugene (jno) Dvurechenski
7d43bafcff KVM: s390: Make provisions for ESCA utilization
This patch updates the routines (sca_*) to provide transparent access
to and manipulation on the data for both Basic and Extended SCA in use.
The kvm.arch.sca is generalized to (void *) to handle BSCA/ESCA cases.
Also the kvm.arch.use_esca flag is provided.
The actual functionality is kept the same.

Signed-off-by: Eugene (jno) Dvurechenski <jno@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-11-30 12:47:08 +01:00
Eugene (jno) Dvurechenski
bc784ccee5 KVM: s390: Introduce new structures
This patch adds new structures and updates some existing ones to
provide the base for Extended SCA functionality.

The old sca_* structures were renamed to bsca_* to keep things uniform.

The access to fields of SIGP controls were turned into bitfields instead
of hardcoded bitmasks.

Signed-off-by: Eugene (jno) Dvurechenski <jno@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-11-30 12:47:07 +01:00
Eugene (jno) Dvurechenski
a5bd764734 KVM: s390: Generalize access to SIGP controls
This patch generalizes access to the SIGP controls, which is a part of SCA.
This is to prepare for upcoming introduction of Extended SCA support.

Signed-off-by: Eugene (jno) Dvurechenski <jno@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-11-30 12:47:06 +01:00
David Hildenbrand
152e9f65d6 KVM: s390: fix wrong lookup of VCPUs by array index
For now, VCPUs were always created sequentially with incrementing
VCPU ids. Therefore, the index in the VCPUs array matched the id.

As sequential creation might change with cpu hotplug, let's use
the correct lookup function to find a VCPU by id, not array index.

Let's also use kvm_lookup_vcpu() for validation of the sending VCPU
on external call injection.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: stable@vger.kernel.org # db27a7a KVM: Provide function for VCPU lookup by id
2015-11-19 14:47:43 +01:00
David Hildenbrand
b85de33a1a KVM: s390: avoid memory overwrites on emergency signal injection
Commit 383d0b0501 ("KVM: s390: handle pending local interrupts via
bitmap") introduced a possible memory overwrite from user space.

User space could pass an invalid emergency signal code (sending VCPU)
and therefore exceed the bitmap. Let's take care of this case and
check that the id is in the valid range.

Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org # v3.19+ db27a7a KVM: Provide function for VCPU lookup by id
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-11-19 14:47:32 +01:00
David Hildenbrand
60417fcc2b KVM: s390: factor out reading of the guest TOD clock
Let's factor this out and always use get_tod_clock_fast() when
reading the guest TOD.

STORE CLOCK FAST does not do serialization and, therefore, might
result in some fuzziness between different processors in a way
that subsequent calls on different CPUs might have time stamps that
are earlier. This semantics is fine though for all KVM use cases.
To make it obvious that the new function has STORE CLOCK FAST
semantics we name it kvm_s390_get_tod_clock_fast.

With this patch, we only have a handful of places were we
have to care about STP sync (using preempt_disable() logic).

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-10-13 15:50:35 +02:00
David Hildenbrand
238293b14d KVM: s390: correctly handle injection of pgm irqs and per events
PER events can always co-exist with other program interrupts.

For now, we always overwrite all program interrupt parameters when
injecting any type of program interrupt.

Let's handle that correctly by only overwriting the relevant portion of
the program interrupt parameters. Therefore we can now inject PER events
and ordinary program interrupts concurrently, resulting in no loss of
program interrupts. This will especially by helpful when manually detecting
PER events later - as both types might be triggered during one SIE exit.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-10-13 15:50:34 +02:00
David Hildenbrand
66933b78e3 KVM: s390: simplify in-kernel program irq injection
The main reason to keep program injection in kernel separated until now
was that we were able to do some checking, if really only the owning
thread injects program interrupts (via waitqueue_active(li->wq)).

This BUG_ON was never triggered and the chances of really hitting it, if
another thread injected a program irq to another vcpu, were very small.

Let's drop this check and turn kvm_s390_inject_program_int() and
kvm_s390_inject_prog_irq() into simple inline functions that makes use of
kvm_s390_inject_vcpu().

__must_check can be dropped as they are implicitely given by
kvm_s390_inject_vcpu(), to avoid ugly long function prototypes.

Reviewed-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-10-13 15:50:34 +02:00
David Hildenbrand
4d32ad6bec KVM: s390: drop out early in kvm_s390_has_irq()
Let's get rid of the local variable and exit directly if we found
any pending interrupt. This is not only faster, but also better
readable.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-10-13 15:50:33 +02:00
David Hildenbrand
118b862b15 KVM: s390: kvm_arch_vcpu_runnable already cares about timer interrupts
We can remove that double check.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-10-13 15:50:33 +02:00
David Hildenbrand
5f94c58ed0 KVM: s390: set interception requests for all floating irqs
No need to separate pending and floating irqs when setting interception
requests. Let's do it for all equally.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-10-13 15:50:33 +02:00
David Hildenbrand
fee0e0fdb2 KVM: s390: disabled wait cares about machine checks, not PER
We don't care about program event recording irqs (synchronous
program irqs) but asynchronous irqs when checking for disabled
wait. Machine checks were missing.

Let's directly switch to the functions we have for that purpose
instead of testing once again for magic bits.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-10-13 15:50:32 +02:00
Christian Borntraeger
f59922b47e KVM: s390: remove unused variable in __inject_vm
the float int structure is no longer used in __inject_vm.

Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-10-13 15:50:27 +02:00
Linus Torvalds
ca520cab25 Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking and atomic updates from Ingo Molnar:
 "Main changes in this cycle are:

   - Extend atomic primitives with coherent logic op primitives
     (atomic_{or,and,xor}()) and deprecate the old partial APIs
     (atomic_{set,clear}_mask())

     The old ops were incoherent with incompatible signatures across
     architectures and with incomplete support.  Now every architecture
     supports the primitives consistently (by Peter Zijlstra)

   - Generic support for 'relaxed atomics':

       - _acquire/release/relaxed() flavours of xchg(), cmpxchg() and {add,sub}_return()
       - atomic_read_acquire()
       - atomic_set_release()

     This came out of porting qwrlock code to arm64 (by Will Deacon)

   - Clean up the fragile static_key APIs that were causing repeat bugs,
     by introducing a new one:

       DEFINE_STATIC_KEY_TRUE(name);
       DEFINE_STATIC_KEY_FALSE(name);

     which define a key of different types with an initial true/false
     value.

     Then allow:

       static_branch_likely()
       static_branch_unlikely()

     to take a key of either type and emit the right instruction for the
     case.  To be able to know the 'type' of the static key we encode it
     in the jump entry (by Peter Zijlstra)

   - Static key self-tests (by Jason Baron)

   - qrwlock optimizations (by Waiman Long)

   - small futex enhancements (by Davidlohr Bueso)

   - ... and misc other changes"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (63 commits)
  jump_label/x86: Work around asm build bug on older/backported GCCs
  locking, ARM, atomics: Define our SMP atomics in terms of _relaxed() operations
  locking, include/llist: Use linux/atomic.h instead of asm/cmpxchg.h
  locking/qrwlock: Make use of _{acquire|release|relaxed}() atomics
  locking/qrwlock: Implement queue_write_unlock() using smp_store_release()
  locking/lockref: Remove homebrew cmpxchg64_relaxed() macro definition
  locking, asm-generic: Add _{relaxed|acquire|release}() variants for 'atomic_long_t'
  locking, asm-generic: Rework atomic-long.h to avoid bulk code duplication
  locking/atomics: Add _{acquire|release|relaxed}() variants of some atomic operations
  locking, compiler.h: Cast away attributes in the WRITE_ONCE() magic
  locking/static_keys: Make verify_keys() static
  jump label, locking/static_keys: Update docs
  locking/static_keys: Provide a selftest
  jump_label: Provide a self-test
  s390/uaccess, locking/static_keys: employ static_branch_likely()
  x86, tsc, locking/static_keys: Employ static_branch_likely()
  locking/static_keys: Add selftest
  locking/static_keys: Add a new static_key interface
  locking/static_keys: Rework update logic
  locking/static_keys: Add static_key_{en,dis}able() helpers
  ...
2015-09-03 15:46:07 -07:00
Fan Zhang
fdf036507f KVM: s390: host STP toleration for VMs
If the host has STP enabled, the TOD of the host will be changed during
synchronization phases. These are performed during a stop_machine() call.

As the guest TOD is based on the host TOD, we have to make sure that:
- no VCPU is in the SIE (implicitly guaranteed via stop_machine())
- manual guest TOD calculations are not affected

"Epoch" is the guest TOD clock delta to the host TOD clock. We have to
adjust that value during the STP synchronization and make sure that code
that accesses the epoch won't get interrupted in between (via disabling
preemption).

Signed-off-by: Fan Zhang <zhangfan@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-08-04 14:38:37 +02:00
David Hildenbrand
a37281b636 KVM: s390: more irq names for trace events
This patch adds names for missing irq types to the trace events.
In order to identify adapter irqs, the define is moved from
interrupt.c to the other basic irq defines in uapi/linux/kvm.h.

Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-07-29 11:02:34 +02:00
Christian Borntraeger
3f24ba150c KVM: s390: Fixup interrupt vcpu event messages and levels
This reworks the debug logging for interrupt related logs.
Several changes:
- unify program int/irq
- improve decoding (e.g. use mcic instead of parm64 for machine
  check injection)
- remove useless interrupt type number (the name is enough)
- rename "interrupt:" to "deliver:" as the other side is called "inject"
- use log level 3 for state changing and/or seldom events (like machine
  checks, restart..)
- use log level 4 for frequent events
- use 0x prefix for hex numbers
- add pfault done logging
- move some tracing outside spinlock

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
2015-07-29 11:02:34 +02:00
David Hildenbrand
ed2afcfa13 KVM: s390: remove "from (user|kernel)" from irq injection messages
The "from user"/"from kernel" part of the log/trace messages is not
always correct anymore and therefore not really helpful.

Let's remove that part from the log + trace messages. For program
interrupts, we can now move the logging/tracing part into the real
injection function, as already done for the other injection functions.

Reviewed-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-07-29 11:02:33 +02:00
Christian Borntraeger
71db35d26d KVM: s390: VCPU_EVENT cleanup for prefix changes
SPX (SET PREFIX)  and SIGP (Set prefix) can change the prefix
register of a CPU. As sigp set prefix may be handled in user
space (KVM_CAP_S390_USER_SIGP), we would not log the changes
triggered via SIGP in that case. Let's have just one VCPU_EVENT
at the central location that tracks prefix changes.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
2015-07-29 11:02:33 +02:00
Peter Zijlstra
805de8f43c atomic: Replace atomic_{set,clear}_mask() usage
Replace the deprecated atomic_{set,clear}_mask() usage with the now
ubiquous atomic_{or,andnot}() functions.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27 14:06:24 +02:00
Linus Torvalds
4e241557fc The bulk of the changes here is for x86. And for once it's not
for silicon that no one owns: these are really new features for
 everyone.
 
 * ARM: several features are in progress but missed the 4.2 deadline.
 So here is just a smattering of bug fixes, plus enabling the VFIO
 integration.
 
 * s390: Some fixes/refactorings/optimizations, plus support for
 2GB pages.
 
 * x86: 1) host and guest support for marking kvmclock as a stable
 scheduler clock. 2) support for write combining. 3) support for
 system management mode, needed for secure boot in guests. 4) a bunch
 of cleanups required for 2+3.  5) support for virtualized performance
 counters on AMD; 6) legacy PCI device assignment is deprecated and
 defaults to "n" in Kconfig; VFIO replaces it.  On top of this there are
 also bug fixes and eager FPU context loading for FPU-heavy guests.
 
 * Common code: Support for multiple address spaces; for now it is
 used only for x86 SMM but the s390 folks also have plans.
 
 There are some x86 conflicts, one with the rc8 pull request and
 the rest with Ingo's FPU rework.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull first batch of KVM updates from Paolo Bonzini:
 "The bulk of the changes here is for x86.  And for once it's not for
  silicon that no one owns: these are really new features for everyone.

  Details:

   - ARM:
        several features are in progress but missed the 4.2 deadline.
        So here is just a smattering of bug fixes, plus enabling the
        VFIO integration.

   - s390:
        Some fixes/refactorings/optimizations, plus support for 2GB
        pages.

   - x86:
        * host and guest support for marking kvmclock as a stable
          scheduler clock.
        * support for write combining.
        * support for system management mode, needed for secure boot in
          guests.
        * a bunch of cleanups required for the above
        * support for virtualized performance counters on AMD
        * legacy PCI device assignment is deprecated and defaults to "n"
          in Kconfig; VFIO replaces it

        On top of this there are also bug fixes and eager FPU context
        loading for FPU-heavy guests.

   - Common code:
        Support for multiple address spaces; for now it is used only for
        x86 SMM but the s390 folks also have plans"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (124 commits)
  KVM: s390: clear floating interrupt bitmap and parameters
  KVM: x86/vPMU: Enable PMU handling for AMD PERFCTRn and EVNTSELn MSRs
  KVM: x86/vPMU: Implement AMD vPMU code for KVM
  KVM: x86/vPMU: Define kvm_pmu_ops to support vPMU function dispatch
  KVM: x86/vPMU: introduce kvm_pmu_msr_idx_to_pmc
  KVM: x86/vPMU: reorder PMU functions
  KVM: x86/vPMU: whitespace and stylistic adjustments in PMU code
  KVM: x86/vPMU: use the new macros to go between PMC, PMU and VCPU
  KVM: x86/vPMU: introduce pmu.h header
  KVM: x86/vPMU: rename a few PMU functions
  KVM: MTRR: do not map huge page for non-consistent range
  KVM: MTRR: simplify kvm_mtrr_get_guest_memory_type
  KVM: MTRR: introduce mtrr_for_each_mem_type
  KVM: MTRR: introduce fixed_mtrr_addr_* functions
  KVM: MTRR: sort variable MTRRs
  KVM: MTRR: introduce var_mtrr_range
  KVM: MTRR: introduce fixed_mtrr_segment table
  KVM: MTRR: improve kvm_mtrr_get_guest_memory_type
  KVM: MTRR: do not split 64 bits MSR content
  KVM: MTRR: clean up mtrr default type
  ...
2015-06-24 09:36:49 -07:00
Jens Freimann
f2ae45edbc KVM: s390: clear floating interrupt bitmap and parameters
commit 6d3da24141 ("KVM: s390: deliver floating interrupts in order
of priority") introduced a regression for the reset handling.

We don't clear the bitmap of pending floating interrupts
and interrupt parameters. This could result in stale interrupts
even after a reset. Let's fix this by clearing the pending bitmap
and the parameters for service and machine check interrupts.

Cc: stable@vger.kernel.org # 4.1
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-06-23 17:02:39 +02:00
David Hildenbrand
37c5f6c86c s390/sclp: unify basic sclp access by exposing "struct sclp"
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: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-05-13 09:58:17 +02:00
David Hildenbrand
96e0ed23dc KVM: s390: factor out and optimize floating irq VCPU kick
This patch factors out the search for a floating irq destination
VCPU as well as the kicking of the found VCPU. The search is optimized
in the following ways:

1. stopped VCPUs can't take any floating interrupts, so try to find an
   operating one. We have to take care of the special case where all
   VCPUs are stopped and we don't have any valid destination.

2. use online_vcpus, not KVM_MAX_VCPU. This speeds up the search
   especially if KVM_MAX_VCPU is increased one day. As these VCPU
   objects are initialized prior to increasing online_vcpus, we can be
   sure that they exist.

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Reviewed-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-05-08 15:51:16 +02:00
Jens Freimann
ffeca0ae88 KVM: s390: optimize interrupt handling round trip time
We can avoid checking guest control registers and guest PSW as well
as all the masking and calculations on the interrupt masks when
no interrupts are pending.

Also, the check for IRQ_PEND_COUNT can be removed, because we won't
enter the while loop if no interrupts are pending and invalid interrupt
types can't be injected.

Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-05-08 15:51:15 +02:00
David Hildenbrand
b938eacea0 KVM: s390: fix external call injection without sigp interpretation
Commit ea5f496925 ("KVM: s390: only one external call may be pending
at a time") introduced a bug on machines that don't have SIGP
interpretation facility installed.
The injection of an external call will now always fail with -EBUSY
(if none is already pending).

This leads to the following symptoms:
- An external call will be injected but with the wrong "src cpu id",
  as this id will not be remembered.
- The target vcpu will not be woken up, therefore the guest will hang if
  it cannot deal with unexpected failures of the SIGP EXTERNAL CALL
  instruction.
- If an external call is already pending, -EBUSY will not be reported.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org # v4.0
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-05-08 15:51:12 +02:00
Jens Freimann
816c7667ea KVM: s390: migrate vcpu interrupt state
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: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2015-03-31 21:07:31 +02:00
Jens Freimann
79e87a103d KVM: s390: refactor vcpu injection function
Let's provide a version of kvm_s390_inject_vcpu() that
does not acquire the local-interrupt lock and skips
waking up the vcpu.
To be used in a later patch for vcpu-local interrupt migration,
where we are already holding the lock.

Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2015-03-31 21:07:30 +02:00
David Hildenbrand
b4aec92567 KVM: s390: cpu timer irq priority
We now have a mechanism for delivering interrupts according to their priority.

Let's inject them using our new infrastructure (instead of letting only hardware
handle them), so we can be sure that the irq priorities are satisfied.

For s390, the cpu timer and the clock comparator are to be checked for common
code kvm_cpu_has_pending_timer(), although the cpu timer is only stepped when
the guest is being executed.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2015-03-31 21:07:29 +02:00
Jens Freimann
6d3da24141 KVM: s390: deliver floating interrupts in order of priority
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: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2015-03-31 21:07:27 +02:00
Jens Freimann
94aa033efc KVM: s390: fix get_all_floating_irqs
This fixes a bug introduced with commit c05c4186bb ("KVM: s390:
add floating irq controller").

get_all_floating_irqs() does copy_to_user() while holding
a spin lock. Let's fix this by filling a temporary buffer
first and copy it to userspace after giving up the lock.

Cc: <stable@vger.kernel.org> # 3.18+: 69a8d45626 KVM: s390: no need to hold...

Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2015-03-31 21:05:51 +02:00
David Hildenbrand
2ba4596852 KVM: s390: store the breaking-event address on pgm interrupts
If the PER-3 facility is installed, the breaking-event address is to be
stored in the low core.

There is no facility bit for PER-3 in stfl(e) and Linux always uses the
value at address 272 no matter if PER-3 is available or not.
We can't hide its existence from the guest. All program interrupts
injected via the SIE automatically store this information if the PER-3
facility is available in the hypervisor. Also the itdb contains the
address automatically.

As there is no switch to turn this mechanism off, let's simply make it
consistent and also store the breaking event address in case of manual
program interrupt injection.

Reviewed-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2015-03-31 13:49:08 +02:00
Eric Farman
bc17de7c96 KVM: s390: Machine Check
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: Eric Farman <farman@linux.vnet.ibm.com>
Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-03-06 13:49:34 +01:00
Eric Farman
403c8648cb KVM: s390: Vector exceptions
A new exception type for vector instructions is introduced with
the new processor, but is handled exactly like a Data Exception
which is already handled by the system.

Signed-off-by: Eric Farman <farman@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-03-06 13:49:33 +01:00
Thomas Huth
33b412acd3 KVM: s390: Use insn_length() to calculate length of instruction
The common s390 function insn_length() results in slightly smaller
(and thus hopefully faster) code than the calculation of the
instruction length via a lookup-table. So let's use that function
in the interrupt delivery code, too.

Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-03-06 13:40:48 +01:00
Thomas Huth
a9a846fd5c KVM: s390: Nullify instruction for certain program exceptions
When certain program exceptions (e.g. DAT access exceptions) occur,
the current instruction has to be nullified, i.e. the old PSW that
gets written into the low-core has to point to the beginning of the
instruction again, and not to the beginning of the next instruction.
Thus we have to rewind the PSW before writing it into the low-core.
The list of nullifying exceptions can be found in the POP, chapter 6,
figure 6-1 ("Interruption Action").

Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-03-06 13:40:40 +01:00
David Hildenbrand
15462e37ca KVM: s390: reinjection of irqs can fail in the tpi handler
The reinjection of an I/O interrupt can fail if the list is at the limit
and between the dequeue and the reinjection, another I/O interrupt is
injected (e.g. if user space floods kvm with I/O interrupts).

This patch avoids this memory leak and returns -EFAULT in this special
case. This error is not recoverable, so let's fail hard. This can later
be avoided by not dequeuing the interrupt but working directly on the
locked list.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org # 3.16+
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-03-06 13:40:37 +01:00
David Hildenbrand
8e2207cdd0 KVM: s390: floating irqs: fix user triggerable endless loop
If a vm with no VCPUs is created, the injection of a floating irq
leads to an endless loop in the kernel.

Let's skip the search for a destination VCPU for a floating irq if no
VCPUs were created.

Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org # v3.15+
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-02-09 12:44:10 +01:00
Jens Freimann
0eb135ff9f KVM: s390: remove redundant setting of interrupt type
Setting inti->type again is unnecessary here, so let's
remove this.

Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-01-23 13:25:42 +01:00
Jens Freimann
94d1f564ad KVM: s390: fix bug in interrupt parameter check
When we convert interrupt data from struct kvm_s390_interrupt to
struct kvm_s390_irq we need to check the data in the input parameter
not the output parameter.

Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-01-23 13:25:42 +01:00
David Hildenbrand
428d53be5e KVM: s390: avoid memory leaks if __inject_vm() fails
We have to delete the allocated interrupt info if __inject_vm() fails.

Otherwise user space can keep flooding kvm with floating interrupts and
provoke more and more memory leaks.

Reported-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org # v3.15+
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-01-23 13:25:41 +01:00
Jens Freimann
556cc0dab1 KVM: s390: trace correct values for set prefix and machine checks
When injecting SIGP set prefix or a machine check, we trace
the values in our per-vcpu local_int data structure instead
of the parameters passed to the function.

Fix this by changing the trace statement to use the correct values.

Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-01-23 13:25:39 +01:00
Jens Freimann
49538d1238 KVM: s390: fix bug in sigp emergency signal injection
Currently we are always setting the wrong bit in the
bitmap for pending emergency signals. Instead of using
emerg.code from the passed in irq parameter, we use the
value in our per-vcpu local_int structure, which is always zero.
That means all emergency signals will have address 0 as parameter.
If two CPUs send a SIGP to the same target, one might be lost.

Let's fix this by using the value from the parameter and
also trace the correct value.

Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-01-23 13:25:39 +01:00
Christian Borntraeger
69a8d45626 KVM: s390: no need to hold the kvm->mutex for floating interrupts
The kvm mutex was (probably) used to protect against cpu hotplug.
The current code no longer needs to protect against that, as we only
rely on CPU data structures that are guaranteed to be available
if we can access the CPU. (e.g. vcpu_create will put the cpu
in the array AFTER the cpu is ready).

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
2015-01-23 13:25:37 +01:00
David Hildenbrand
ea5f496925 KVM: s390: only one external call may be pending at a time
Only one external call may be pending at a vcpu at a time. For this
reason, we have to detect whether the SIGP externcal call interpretation
facility is available. If so, all external calls have to be injected
using this mechanism.

SIGP EXTERNAL CALL orders have to return whether another external
call is already pending. This check was missing until now.

SIGP SENSE hasn't returned yet in all conditions whether an external
call was pending.

If a SIGP EXTERNAL CALL irq is to be injected and one is already
pending, -EBUSY is returned.

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-01-23 13:25:36 +01:00
David Hildenbrand
a3a9c59a68 KVM: s390: SIGP SET PREFIX cleanup
This patch cleanes up the the SIGP SET PREFIX code.

A SIGP SET PREFIX irq may only be injected if the target vcpu is
stopped. Let's move the checking code into the injection code and
return -EBUSY if the target vcpu is not stopped.

Reviewed-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-01-23 13:25:34 +01:00
David Hildenbrand
9a022067ad KVM: s390: a VCPU may only stop when no interrupts are left pending
As a SIGP STOP is an interrupt with the least priority, it may only result
in stop of the vcpu when no other interrupts are left pending.

To detect whether a non-stop irq is pending, we need a way to mask out
stop irqs from the general kvm_cpu_has_interrupt() function. For this
reason, the existing function (with an outdated name) is replaced by
kvm_s390_vcpu_has_irq() which allows to mask out pending stop irqs.

Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-01-23 13:25:34 +01:00
David Hildenbrand
6cddd432e3 KVM: s390: handle stop irqs without action_bits
This patch removes the famous action_bits and moves the handling of
SIGP STOP AND STORE STATUS directly into the SIGP STOP interrupt.

The new local interrupt infrastructure is used to track pending stop
requests.

STOP irqs are the only irqs that don't get actively delivered. They
remain pending until the stop function is executed (=stop intercept).

If another STOP irq is already pending, -EBUSY will now be returned
(needed for the SIGP handling code).

Migration of pending SIGP STOP (AND STORE STATUS) orders should now
be supported out of the box.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-01-23 13:25:33 +01:00
David Hildenbrand
2822545f9f KVM: s390: new parameter for SIGP STOP irqs
In order to get rid of the action_flags and to properly migrate pending SIGP
STOP irqs triggered e.g. by SIGP STOP AND STORE STATUS, we need to remember
whether to store the status when stopping.

For this reason, a new parameter (flags) for the SIGP STOP irq is introduced.
These flags further define details of the requested STOP and can be easily
migrated.

Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-01-23 13:25:33 +01:00