The LPI pending status for a GICv3 redistributor is held in a table
in (guest) memory. To achieve reasonable performance, we cache the
pending bit in our struct vgic_irq. The initial pending state must be
read from guest memory upon enabling LPIs for this redistributor.
As we can't access the guest memory while we hold the lpi_list spinlock,
we create a snapshot of the LPI list and iterate over that.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Introduce a new KVM device that represents an ARM Interrupt Translation
Service (ITS) controller. Since there can be multiple of this per guest,
we can't piggy back on the existing GICv3 distributor device, but create
a new type of KVM device.
On the KVM_CREATE_DEVICE ioctl we allocate and initialize the ITS data
structure and store the pointer in the kvm_device data.
Upon an explicit init ioctl from userland (after having setup the MMIO
address) we register the handlers with the kvm_io_bus framework.
Any reference to an ITS thus has to go via this interface.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
The ARM GICv3 ITS emulation code goes into a separate file, but needs
to be connected to the GICv3 emulation, of which it is an option.
The ITS MMIO handlers require the respective ITS pointer to be passed in,
so we amend the existing VGIC MMIO framework to let it cope with that.
Also we introduce the basic ITS data structure and initialize it, but
don't return any success yet, as we are not yet ready for the show.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
In the moment our struct vgic_irq's are statically allocated at guest
creation time. So getting a pointer to an IRQ structure is trivial and
safe. LPIs are more dynamic, they can be mapped and unmapped at any time
during the guest's _runtime_.
In preparation for supporting LPIs we introduce reference counting for
those structures using the kernel's kref infrastructure.
Since private IRQs and SPIs are statically allocated, we avoid actually
refcounting them, since they would never be released anyway.
But we take provisions to increase the refcount when an IRQ gets onto a
VCPU list and decrease it when it gets removed. Also this introduces
vgic_put_irq(), which wraps kref_put and hides the release function from
the callers.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
kvm_register_device_ops() can return an error, so lets check its return
value and propagate this up the call chain.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
map_resources is the last initialization step. It is executed on
first VCPU run. At that stage the code checks that userspace has provided
the base addresses for the relevant VGIC regions, which depend on the
type of VGIC that is exposed to the guest. Also we check if the two
regions overlap.
If the checks succeeded, we register the respective register frames with
the kvm_io_bus framework.
If we emulate a GICv2, the function also forces vgic_init execution if
it has not been executed yet. Also we map the virtual GIC CPU interface
onto the guest's CPU interface.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
This patch allocates and initializes the data structures used
to model the vgic distributor and virtual cpu interfaces. At that
stage the number of IRQs and number of virtual CPUs is frozen.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Implements kvm_vgic_hyp_init and vgic_probe function.
This uses the new firmware independent VGIC probing to support both ACPI
and DT based systems (code from Marc Zyngier).
The vgic_global struct is enriched with new fields populated
by those functions.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Using the VMCR accessors we provide access to GIC CPU interface state
to userland by wiring it up to the existing userland interface.
[Marc: move and make VMCR accessors static, streamline MMIO handlers]
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Since the GIC CPU interface is always virtualized by the hardware,
we don't have CPU interface state information readily available in our
emulation if userland wants to save or restore it.
Fortunately the GIC hypervisor interface provides the VMCR register to
access the required virtual CPU interface bits.
Provide wrappers for GICv2 and GICv3 hosts to have access to this
register.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Userland can access the emulated GIC to save and restore its state
for initialization or migration purposes.
The kvm_io_bus API requires an absolute gpa, which does not fit the
KVM_DEV_ARM_VGIC_GRP_DIST_REGS user API, that only provides relative
offsets. So we provide a wrapper to plug into our MMIO framework and
find the respective register handler.
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
This patch implements the switches for KVM_DEV_ARM_VGIC_GRP_DIST_REGS
and KVM_DEV_ARM_VGIC_GRP_CPU_REGS API which allows the userspace to
access VGIC registers.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
kvm_vgic_addr is used by the userspace to set the base address of
the following register regions, as seen by the guest:
- distributor(v2 and v3),
- re-distributors (v3),
- CPU interface (v2).
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
This patch introduces the skeleton for the KVM device operations
associated to KVM_DEV_TYPE_ARM_VGIC_V2 and KVM_DEV_TYPE_ARM_VGIC_V3.
At that stage kvm_vgic_create is stubbed.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
As in the GICv2 emulation we handle those three registers in one
function.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Create a new file called vgic-mmio-v3.c and describe the GICv3
distributor and redistributor registers there.
This adds a special macro to deal with the split of SGI/PPI in the
redistributor and SPIs in the distributor, which allows us to reuse
the existing GICv2 handlers for those registers which are compatible.
Also we provide a function to deal with the registration of the two
separate redistributor frames per VCPU.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
The priority register handlers are shared between the v2 and v3
emulation, so their implementation goes into vgic-mmio.c, to be
easily referenced from the v3 emulation as well later.
There is a corner case when we change the priority of a pending
interrupt which we don't handle at the moment.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Those three registers are v2 emulation specific, so their implementation
lives entirely in vgic-mmio-v2.c. Also they are handled in one function,
as their implementation is pretty simple.
When the guest enables the distributor, we kick all VCPUs to get
potentially pending interrupts serviced.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Create vgic-mmio-v2.c to describe GICv2 emulation specific handlers
using the initializer macros provided by the VGIC MMIO framework.
Provide a function to register the GICv2 distributor registers to
the kvm_io_bus framework.
The actual handler functions are still stubs in this patch.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
As the GICv3 virtual interface registers differ from their GICv2
siblings, we need different handlers for processing maintenance
interrupts and reading/writing to the LRs.
Implement the respective handler functions and connect them to
existing code to be called if the host is using a GICv3.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Processing maintenance interrupts and accessing the list registers
are dependent on the host's GIC version.
Introduce vgic-v2.c to contain GICv2 specific functions.
Implement the GICv2 specific code for syncing the emulation state
into the VGIC registers.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Implement the framework for syncing IRQs between our emulation and
the list registers, which represent the guest's view of IRQs.
This is done in kvm_vgic_flush_hwstate and kvm_vgic_sync_hwstate,
which gets called on guest entry and exit.
The code talking to the actual GICv2/v3 hardware is added in the
following patches.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Provide a vgic_queue_irq_unlock() function which decides whether a
given IRQ needs to be queued to a VCPU's ap_list.
This should be called whenever an IRQ becomes pending or enabled,
either as a result of userspace injection, from in-kernel emulated
devices like the architected timer or from MMIO accesses to the
distributor emulation.
Also provides the necessary functions to allow userland to inject an
IRQ to a guest.
Since this is the first code that starts using our locking mechanism, we
add some (hopefully) clear documentation of our locking strategy and
requirements along with this patch.
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
The new VGIC implementation centers around a struct vgic_irq instance
per virtual IRQ.
Provide a function to retrieve the right instance for a given IRQ
number and (in case of private interrupts) the right VCPU.
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>