Stanse found 2 lock imbalances in kvm_request_irq_source_id and
kvm_free_irq_source_id. They omit to unlock kvm->irq_lock on fail paths.

Fix that by adding unlock labels at the end of the functions and jump
there from the fail paths.
Signed-off-by: NJiri Slaby <jirislaby@gmail.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

The only thing it protects now is interrupt injection into lapic and
this can work lockless. Even now with kvm->irq_lock in place access
to lapic is not entirely serialized since vcpu access doesn't take
kvm->irq_lock.
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

The allows removal of irq_lock from the injection path.
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Use RCU locking for mask/ack notifiers lists.
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Mask irq notifier list is already there.
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Maintain back mapping from irqchip/pin to gsi to speedup
interrupt acknowledgment notifications.

[avi: build fix on non-x86/ia64]
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Use gsi indexed array instead of scanning all entries on each interrupt
injection.
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

This removes assumptions that max GSIs is smaller than number of pins.
Sharing is tracked on pin level not GSI level.

[avi: no PIC on ia64]
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Add tracepoint in msi/ioapic/pic set_irq() functions,
in IPI sending and in the point where IRQ is placed into
apic's IRR.
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Irqfd sets level for interrupt to 1 and then to 0.
For MSI, check level so that a single message is sent.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Signed-off-by: NAvi Kivity <avi@redhat.com>

This allows use of the powerful ftrace infrastructure.

See Documentation/trace/ for usage information.

[avi, stephen: various build fixes]
[sheng: fix control register breakage]
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NSheng Yang <sheng@linux.intel.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

[christian: remove unused variables on s390]
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Protect irq injection/acking data structures with a separate irq_lock
mutex. This fixes the following deadlock:

CPU A                               CPU B
kvm_vm_ioctl_deassign_dev_irq()
  mutex_lock(&kvm->lock);            worker_thread()
  -> kvm_deassign_irq()                -> kvm_assigned_dev_interrupt_work_handler()
    -> deassign_host_irq()               mutex_lock(&kvm->lock);
      -> cancel_work_sync() [blocked]

[gleb: fix ia64 path]
Reported-by: NAlex Williamson <alex.williamson@hp.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

kvm_notify_acked_irq does not check irq type, so that it sometimes
interprets msi vector as irq.  As a result, ack notifiers are not
called, which typially hangs the guest.  The fix is to track and
check irq type.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Remove extra tab.
Signed-off-by: NChris Wright <chrisw@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Deliver interrupt during destination matching loop.
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Acked-by: NXiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

The new way does not require additional loop over vcpus to calculate
the one with lowest priority as one is chosen during delivery bitmap
construction.
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

Use kvm_apic_match_dest() in kvm_get_intr_delivery_bitmask() instead
of duplicating the same code. Use kvm_get_intr_delivery_bitmask() in
apic_send_ipi() to figure out ipi destination instead of reimplementing
the logic.
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

ioapic_deliver() and kvm_set_msi() have code duplication. Move
the code into ioapic_deliver_entry() function and call it from
both places.
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

Get rid of ioapic_inj_irq() and ioapic_inj_nmi() functions.
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

Gleb fixed bitmap ops usage in kvm_ioapic_get_delivery_bitmask.

Sheng merged two functions, as well as fixed several issues in
kvm_get_intr_delivery_bitmask
1. deliver_bitmask is a bitmap rather than a unsigned long intereger.
2. Lowest priority target bitmap wrong calculated by mistake.
3. Prevent potential NULL reference.
4. Declaration in include/kvm_host.h caused powerpc compilation warning.
5. Add warning for guest broadcast interrupt with lowest priority delivery mode.
6. Removed duplicate bitmap clean up in caller of kvm_get_intr_delivery_bitmask.
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NSheng Yang <sheng@linux.intel.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

It's also convenient when we extend KVM supported vcpu number in the future.
Signed-off-by: NSheng Yang <sheng@linux.intel.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Would be used with bit ops, and would be easily extended if KVM_MAX_VCPUS is
increased.
Signed-off-by: NSheng Yang <sheng@linux.intel.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

In order to use with bit ops.
Signed-off-by: NSheng Yang <sheng@linux.intel.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Signed-off-by: NSheng Yang <sheng@linux.intel.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Impact: Make symbols static.

Fix this sparse warnings:
  arch/x86/kvm/mmu.c:992:5: warning: symbol 'mmu_pages_add' was not declared. Should it be static?
  arch/x86/kvm/mmu.c:1124:5: warning: symbol 'mmu_pages_next' was not declared. Should it be static?
  arch/x86/kvm/mmu.c:1144:6: warning: symbol 'mmu_pages_clear_parents' was not declared. Should it be static?
  arch/x86/kvm/x86.c:2037:5: warning: symbol 'kvm_read_guest_virt' was not declared. Should it be static?
  arch/x86/kvm/x86.c:2067:5: warning: symbol 'kvm_write_guest_virt' was not declared. Should it be static?
  virt/kvm/irq_comm.c:220:5: warning: symbol 'setup_routing_entry' was not declared. Should it be static?
Signed-off-by: NHannes Eder <hannes@hanneseder.net>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Include the newly introduced msidef.h to solve the build issues.
Signed-off-by: NXiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Return number of CPUs interrupt was successfully injected into or -1 if
none.
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

IRQ injection status is either -1 (if there was no CPU found
that should except the interrupt because IRQ was masked or
ioapic was misconfigured or ...) or >= 0 in that case the
number indicates to how many CPUs interrupt was injected.
If the value is 0 it means that the interrupt was coalesced
and probably should be reinjected.
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Merge MSI userspace interface with IRQ routing table. Notice the API have been
changed, and using IRQ routing table would be the only interface kvm-userspace
supported.
Signed-off-by: NSheng Yang <sheng@linux.intel.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

IRQ ack notifications assume an identity mapping between pin->gsi,
which might not be the case with, for example, HPET.

Translate before acking.
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Acked-by: NGleb Natapov <gleb@redhat.com>

Currently KVM has a static routing from GSI numbers to interrupts (namely,
0-15 are mapped 1:1 to both PIC and IOAPIC, and 16:23 are mapped 1:1 to
the IOAPIC).  This is insufficient for several reasons:

- HPET requires non 1:1 mapping for the timer interrupt
- MSIs need a new method to assign interrupt numbers and dispatch them
- ACPI APIC mode needs to be able to reassign the PCI LINK interrupts to the
  ioapics

This patch implements an interrupt routing table (as a linked list, but this
can be easily changed) and a userspace interface to replace the table.  The
routing table is initialized according to the current hardwired mapping.
Signed-off-by: NAvi Kivity <avi@redhat.com>

Allow clients to request notifications when the guest masks or unmasks a
particular irq line.  This complements irq ack notifications, as the guest
will not ack an irq line that is masked.

Currently implemented for the ioapic only.
Signed-off-by: NAvi Kivity <avi@redhat.com>

Make sure kvm_request_irq_source_id() never returns
KVM_USERSPACE_IRQ_SOURCE_ID.

Likewise, check that kvm_free_irq_source_id() never accepts
KVM_USERSPACE_IRQ_SOURCE_ID.
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

We never pass a NULL notifier pointer here, but we may well
pass a notifier struct which hasn't previously been
registered.

Guard against this by using hlist_del_init() which will
not do anything if the node hasn't been added to the list
and, when removing the node, will ensure that a subsequent
call to hlist_del_init() will be fine too.

Fixes an oops seen when an assigned device is freed before
and IRQ is assigned to it.
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

We will obviously never pass a NULL struct kvm_irq_ack_notifier* to
this functions. They are always embedded in the assigned device
structure, so the assertion add nothing.

The irqchip_in_kernel() assertion is very out of place - clearly
this little abstraction needs to know nothing about the upper
layer details.
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Also remove unnecessary parameter of unregister irq ack notifier.
Signed-off-by: NSheng Yang <sheng@linux.intel.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Every call of kvm_set_irq() should offer an irq_source_id, which is
allocated by kvm_request_irq_source_id(). Based on irq_source_id, we
identify the irq source and implement logical OR for shared level
interrupts.

The allocated irq_source_id can be freed by kvm_free_irq_source_id().

Currently, we support at most sizeof(unsigned long) different irq sources.

[Amit: - rebase to kvm.git HEAD
       - move definition of KVM_USERSPACE_IRQ_SOURCE_ID to common file
       - move kvm_request_irq_source_id to the update_irq ioctl]

[Xiantao: - Add kvm/ia64 stuff and make it work for kvm/ia64 guests]
Signed-off-by: NSheng Yang <sheng@linux.intel.com>
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NXiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>