We currently have some code to clear the list registers on GICv3, but we
never call this code, because the caller got nuked when removing the old
vgic. We also used to have a similar GICv2 part, but that got lost in
the process too.
Let's reintroduce the logic for GICv2 and call the logic when we
initialize the use of hypervisors on the CPU, for example when first
loading KVM or when exiting a low power state.
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Emulate read and write operations to CNTP_TVAL, CNTP_CVAL and CNTP_CTL.
Now VMs are able to use the EL1 physical timer.
Signed-off-by: Jintack Lim <jintack@cs.columbia.edu>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Initialize the emulated EL1 physical timer with the default irq number.
Signed-off-by: Jintack Lim <jintack@cs.columbia.edu>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Now that we have a separate structure for timer context, make functions
generic so that they can work with any timer context, not just the
virtual timer context. This does not change the virtual timer
functionality.
Signed-off-by: Jintack Lim <jintack@cs.columbia.edu>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Make cntvoff per each timer context. This is helpful to abstract kvm
timer functions to work with timer context without considering timer
types (e.g. physical timer or virtual timer).
This also would pave the way for ever doing adjustments of the cntvoff
on a per-CPU basis if that should ever make sense.
Signed-off-by: Jintack Lim <jintack@cs.columbia.edu>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Abstract virtual timer context into a separate structure and change all
callers referring to timer registers, irq state and so on. No change in
functionality.
This is about to become very handy when adding the EL1 physical timer.
Signed-off-by: Jintack Lim <jintack@cs.columbia.edu>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
VGICv3 CPU interface registers are accessed using
KVM_DEV_ARM_VGIC_CPU_SYSREGS ioctl. These registers are accessed
as 64-bit. The cpu MPIDR value is passed along with register id.
It is used to identify the cpu for registers access.
The VM that supports SEIs expect it on destination machine to handle
guest aborts and hence checked for ICC_CTLR_EL1.SEIS compatibility.
Similarly, VM that supports Affinity Level 3 that is required for AArch64
mode, is required to be supported on destination machine. Hence checked
for ICC_CTLR_EL1.A3V compatibility.
The arch/arm64/kvm/vgic-sys-reg-v3.c handles read and write of VGIC
CPU registers for AArch64.
For AArch32 mode, arch/arm/kvm/vgic-v3-coproc.c file is created but
APIs are not implemented.
Updated arch/arm/include/uapi/asm/kvm.h with new definitions
required to compile for AArch32.
The version of VGIC v3 specification is defined here
Documentation/virtual/kvm/devices/arm-vgic-v3.txt
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Pavel Fedin <p.fedin@samsung.com>
Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@cavium.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Add a file to debugfs to read the in-kernel state of the vgic. We don't
do any locking of the entire VGIC state while traversing all the IRQs,
so if the VM is running the user/developer may not see a quiesced state,
but should take care to pause the VM using facilities in user space for
that purpose.
We also don't support LPIs yet, but they can be added easily if needed.
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
One of the goals behind the VGIC redesign was to get rid of cached or
intermediate state in the data structures, but we decided to allow
ourselves to precompute the pending value of an IRQ based on the line
level and pending latch state. However, this has now become difficult
to base proper GICv3 save/restore on, because there is a potential to
modify the pending state without knowing if an interrupt is edge or
level configured.
See the following post and related message for more background:
https://lists.cs.columbia.edu/pipermail/kvmarm/2017-January/023195.html
This commit gets rid of the precomputed pending field in favor of a
function that calculates the value when needed, irq_is_pending().
The soft_pending field is renamed to pending_latch to represent that
this latch is the equivalent hardware latch which gets manipulated by
the input signal for edge-triggered interrupts and when writing to the
SPENDR/CPENDR registers.
After this commit save/restore code should be able to simply restore the
pending_latch state, line_level state, and config state in any order and
get the desired result.
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Current KVM world switch code is unintentionally setting wrong bits to
CNTHCTL_EL2 when E2H == 1, which may allow guest OS to access physical
timer. Bit positions of CNTHCTL_EL2 are changing depending on
HCR_EL2.E2H bit. EL1PCEN and EL1PCTEN are 1st and 0th bits when E2H is
not set, but they are 11th and 10th bits respectively when E2H is set.
In fact, on VHE we only need to set those bits once, not for every world
switch. This is because the host kernel runs in EL2 with HCR_EL2.TGE ==
1, which makes those bits have no effect for the host kernel execution.
So we just set those bits once for guests, and that's it.
Signed-off-by: Jintack Lim <jintack@cs.columbia.edu>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
There is no point in having an extra type for extra confusion. u64 is
unambiguous.
Conversion was done with the following coccinelle script:
@rem@
@@
-typedef u64 cycle_t;
@fix@
typedef cycle_t;
@@
-cycle_t
+u64
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: John Stultz <john.stultz@linaro.org>
This patch allows to build and use vgic-v3 in 32-bit mode.
Unfortunately, it can not be split in several steps without extra
stubs to keep patches independent and bisectable. For instance,
virt/kvm/arm/vgic/vgic-v3.c uses function from vgic-v3-sr.c, handling
access to GICv3 cpu interface from the guest requires vgic_v3.vgic_sre
to be already defined.
It is how support has been done:
* handle SGI requests from the guest
* report configured SRE on access to GICv3 cpu interface from the guest
* required vgic-v3 macros are provided via uapi.h
* static keys are used to select GIC backend
* to make vgic-v3 build KVM_ARM_VGIC_V3 guard is removed along with
the static inlines
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Currently GIC backend is selected via alternative framework and this
is fine. We are going to introduce vgic-v3 to 32-bit world and there
we don't have patching framework in hand, so we can either check
support for GICv3 every time we need to choose which backend to use or
try to optimise it by using static keys. The later looks quite
promising because we can share logic involved in selecting GIC backend
between architectures if both uses static keys.
This patch moves arm64 from alternative to static keys framework for
selecting GIC backend. For that we embed static key into vgic_global
and enable the key during vgic initialisation based on what has
already been exposed by the host GIC driver.
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Now that we have the necessary infrastructure to handle MMIO accesses
in HYP, perform the GICV access on behalf of the guest. This requires
checking that the access is strictly 32bit, properly aligned, and
falls within the expected range.
When all condition are satisfied, we perform the access and tell
the rest of the HYP code that the instruction has been correctly
emulated.
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
In order to efficiently perform the GICV access on behalf of the
guest, we need to be able to avoid going back all the way to
the host kernel.
For this, we introduce a new hook in the world switch code,
conveniently placed just after populating the fault info.
At that point, we only have saved/restored the GP registers,
and we can quickly perform all the required checks (data abort,
translation fault, valid faulting syndrome, not an external
abort, not a PTW).
Coming back from the emulation code, we need to skip the emulated
instruction. This involves an additional bit of save/restore in
order to be able to access the guest's PC (and possibly CPSR if
this is a 32bit guest).
At this stage, no emulation code is provided.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Includes GSI routing support to go along with the new VGIC and a small fix that
has been cooking in -next for a while.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
iQEcBAABAgAGBQJXoydqAAoJEEtpOizt6ddyM3oH/1A4VeG/J9q4fBPXqY2tVWXs
c3P7UgNcrEgUNs/F9ykQY/lb31deecUzaBt1OyTf+RlsNbihq3dQdYcBhxtUODw/
Faok582ya3UFgLW+IRHcID0EbkVOpIzMhOStYsnU/Dz7HG1JL9HdPzwkid7iu9LT
fI6yrrBnJFjdWAAQ4BkcEKBENRsY8NTs7jX5vnFA92MkUBby7BmariPDD3FtrB+f
Ob9B7CxM30pNqsN7OA/QvFOHMJHxf3s1TBKwmPHe5TLIfSzV1YxcEGiMc0lWqF4v
BT8ZeMGCtjDw94tND1DskfQQRPaMqPmGuRTrAW/IuE2n92bFtbqIqs7Cbw0fzLE=
=Vm6Q
-----END PGP SIGNATURE-----
Merge tag 'kvm-arm-for-4.8-take2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD
KVM/ARM Changes for v4.8 - Take 2
Includes GSI routing support to go along with the new VGIC and a small fix that
has been cooking in -next for a while.
VGIC implementation.
- s390: support for trapping software breakpoints, nested virtualization
(vSIE), the STHYI opcode, initial extensions for CPU model support.
- MIPS: support for MIPS64 hosts (32-bit guests only) and lots of cleanups,
preliminary to this and the upcoming support for hardware virtualization
extensions.
- x86: support for execute-only mappings in nested EPT; reduced vmexit
latency for TSC deadline timer (by about 30%) on Intel hosts; support for
more than 255 vCPUs.
- PPC: bugfixes.
The ugly bit is the conflicts. A couple of them are simple conflicts due
to 4.7 fixes, but most of them are with other trees. There was definitely
too much reliance on Acked-by here. Some conflicts are for KVM patches
where _I_ gave my Acked-by, but the worst are for this pull request's
patches that touch files outside arch/*/kvm. KVM submaintainers should
probably learn to synchronize better with arch maintainers, with the
latter providing topic branches whenever possible instead of Acked-by.
This is what we do with arch/x86. And I should learn to refuse pull
requests when linux-next sends scary signals, even if that means that
submaintainers have to rebase their branches.
Anyhow, here's the list:
- arch/x86/kvm/vmx.c: handle_pcommit and EXIT_REASON_PCOMMIT was removed
by the nvdimm tree. This tree adds handle_preemption_timer and
EXIT_REASON_PREEMPTION_TIMER at the same place. In general all mentions
of pcommit have to go.
There is also a conflict between a stable fix and this patch, where the
stable fix removed the vmx_create_pml_buffer function and its call.
- virt/kvm/kvm_main.c: kvm_cpu_notifier was removed by the hotplug tree.
This tree adds kvm_io_bus_get_dev at the same place.
- virt/kvm/arm/vgic.c: a few final bugfixes went into 4.7 before the
file was completely removed for 4.8.
- include/linux/irqchip/arm-gic-v3.h: this one is entirely our fault;
this is a change that should have gone in through the irqchip tree and
pulled by kvm-arm. I think I would have rejected this kvm-arm pull
request. The KVM version is the right one, except that it lacks
GITS_BASER_PAGES_SHIFT.
- arch/powerpc: what a mess. For the idle_book3s.S conflict, the KVM
tree is the right one; everything else is trivial. In this case I am
not quite sure what went wrong. The commit that is causing the mess
(fd7bacbca4, "KVM: PPC: Book3S HV: Fix TB corruption in guest exit
path on HMI interrupt", 2016-05-15) touches both arch/powerpc/kernel/
and arch/powerpc/kvm/. It's large, but at 396 insertions/5 deletions
I guessed that it wasn't really possible to split it and that the 5
deletions wouldn't conflict. That wasn't the case.
- arch/s390: also messy. First is hypfs_diag.c where the KVM tree
moved some code and the s390 tree patched it. You have to reapply the
relevant part of commits 6c22c98637, plus all of e030c1125e, to
arch/s390/kernel/diag.c. Or pick the linux-next conflict
resolution from http://marc.info/?l=kvm&m=146717549531603&w=2.
Second, there is a conflict in gmap.c between a stable fix and 4.8.
The KVM version here is the correct one.
I have pushed my resolution at refs/heads/merge-20160802 (commit
3d1f53419842) at git://git.kernel.org/pub/scm/virt/kvm/kvm.git.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.22 (GNU/Linux)
iQEcBAABAgAGBQJXoGm7AAoJEL/70l94x66DugQIAIj703ePAFepB/fCrKHkZZia
SGrsBdvAtNsOhr7FQ5qvvjLxiv/cv7CymeuJivX8H+4kuUHUllDzey+RPHYHD9X7
U6n1PdCH9F15a3IXc8tDjlDdOMNIKJixYuq1UyNZMU6NFwl00+TZf9JF8A2US65b
x/41W98ilL6nNBAsoDVmCLtPNWAqQ3lajaZELGfcqRQ9ZGKcAYOaLFXHv2YHf2XC
qIDMf+slBGSQ66UoATnYV2gAopNlWbZ7n0vO6tE2KyvhHZ1m399aBX1+k8la/0JI
69r+Tz7ZHUSFtmlmyByi5IAB87myy2WQHyAPwj+4vwJkDGPcl0TrupzbG7+T05Y=
=42ti
-----END PGP SIGNATURE-----
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Paolo Bonzini:
- ARM: GICv3 ITS emulation and various fixes. Removal of the
old VGIC implementation.
- s390: support for trapping software breakpoints, nested
virtualization (vSIE), the STHYI opcode, initial extensions
for CPU model support.
- MIPS: support for MIPS64 hosts (32-bit guests only) and lots
of cleanups, preliminary to this and the upcoming support for
hardware virtualization extensions.
- x86: support for execute-only mappings in nested EPT; reduced
vmexit latency for TSC deadline timer (by about 30%) on Intel
hosts; support for more than 255 vCPUs.
- PPC: bugfixes.
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (302 commits)
KVM: PPC: Introduce KVM_CAP_PPC_HTM
MIPS: Select HAVE_KVM for MIPS64_R{2,6}
MIPS: KVM: Reset CP0_PageMask during host TLB flush
MIPS: KVM: Fix ptr->int cast via KVM_GUEST_KSEGX()
MIPS: KVM: Sign extend MFC0/RDHWR results
MIPS: KVM: Fix 64-bit big endian dynamic translation
MIPS: KVM: Fail if ebase doesn't fit in CP0_EBase
MIPS: KVM: Use 64-bit CP0_EBase when appropriate
MIPS: KVM: Set CP0_Status.KX on MIPS64
MIPS: KVM: Make entry code MIPS64 friendly
MIPS: KVM: Use kmap instead of CKSEG0ADDR()
MIPS: KVM: Use virt_to_phys() to get commpage PFN
MIPS: Fix definition of KSEGX() for 64-bit
KVM: VMX: Add VMCS to CPU's loaded VMCSs before VMPTRLD
kvm: x86: nVMX: maintain internal copy of current VMCS
KVM: PPC: Book3S HV: Save/restore TM state in H_CEDE
KVM: PPC: Book3S HV: Pull out TM state save/restore into separate procedures
KVM: arm64: vgic-its: Simplify MAPI error handling
KVM: arm64: vgic-its: Make vgic_its_cmd_handle_mapi similar to other handlers
KVM: arm64: vgic-its: Turn device_id validation into generic ID validation
...
This patch adds compilation and link against irqchip.
Main motivation behind using irqchip code is to enable MSI
routing code. In the future irqchip routing may also be useful
when targeting multiple irqchips.
Routing standard callbacks now are implemented in vgic-irqfd:
- kvm_set_routing_entry
- kvm_set_irq
- kvm_set_msi
They only are supported with new_vgic code.
Both HAVE_KVM_IRQCHIP and HAVE_KVM_IRQ_ROUTING are defined.
KVM_CAP_IRQ_ROUTING is advertised and KVM_SET_GSI_ROUTING is allowed.
So from now on IRQCHIP routing is enabled and a routing table entry
must exist for irqfd injection to succeed for a given SPI. This patch
builds a default flat irqchip routing table (gsi=irqchip.pin) covering
all the VGIC SPI indexes. This routing table is overwritten by the
first first user-space call to KVM_SET_GSI_ROUTING ioctl.
MSI routing setup is not yet allowed.
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Going from the ITS structure to the corresponding KVM structure
would be quite handy at times. The kvm_device pointer that is
passed at create time is quite convenient for this, so let's
keep a copy of it in the vgic_its structure.
This will be put to a good use in subsequent patches.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Now that all ITS emulation functionality is in place, we advertise
MSI functionality to userland and also the ITS device to the guest - if
userland has configured 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>
LPIs are dynamically created (mapped) at guest runtime and their
actual number can be quite high, but is mostly assigned using a very
sparse allocation scheme. So arrays are not an ideal data structure
to hold the information.
We use a spin-lock protected linked list to hold all mapped LPIs,
represented by their struct vgic_irq. This lock is grouped between the
ap_list_lock and the vgic_irq lock in our locking order.
Also we store a pointer to that struct vgic_irq in our struct its_itte,
so we can easily access it.
Eventually we call our new vgic_get_lpi() from vgic_get_irq(), so
the VGIC code gets transparently access to LPIs.
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>
Add emulation for some basic MMIO registers used in the ITS emulation.
This includes:
- GITS_{CTLR,TYPER,IIDR}
- ID registers
- GITS_{CBASER,CREADR,CWRITER}
(which implement the ITS command buffer handling)
- GITS_BASER<n>
Most of the handlers are pretty straight forward, only the CWRITER
handler is a bit more involved by taking the new its_cmd mutex and
then iterating over the command buffer.
The registers holding base addresses and attributes are sanitised before
storing them.
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 GICv3 redistributor there are the PENDBASER and PROPBASER
registers which we did not emulate so far, as they only make sense
when having an ITS. In preparation for that emulate those MMIO
accesses by storing the 64-bit data written into it into a variable
which we later read in the ITS emulation.
We also sanitise the registers, making sure RES0 regions are respected
and checking for valid memory attributes.
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>
Logically a GICv3 redistributor is assigned to a (v)CPU, so we should
aim to keep redistributor related variables out of our struct vgic_dist.
Let's start by replacing the redistributor related kvm_io_device array
with two members in our existing struct vgic_cpu, which are naturally
per-VCPU and thus don't require any allocation / freeing.
So apart from the better fit with the redistributor design this saves
some code as well.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Eric Auger <eric.auger@redhat.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>
I don't think any single piece of the KVM/ARM code ever generated
as much hatred as the GIC emulation.
It was written by someone who had zero experience in modeling
hardware (me), was riddled with design flaws, should have been
scrapped and rewritten from scratch long before having a remote
chance of reaching mainline, and yet we supported it for a good
three years. No need to mention the names of those who suffered,
the git log is singing their praises.
Thankfully, we now have a much more maintainable implementation,
and we can safely put the grumpy old GIC to rest.
Fellow hackers, please raise your glass in memory of the GIC:
The GIC is dead, long live the GIC!
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
When CONFIG_ARM_PMU is disabled, we get the following build error:
arch/arm64/kvm/sys_regs.c: In function 'pmu_counter_idx_valid':
arch/arm64/kvm/sys_regs.c:564:27: error: 'ARMV8_PMU_CYCLE_IDX' undeclared (first use in this function)
if (idx >= val && idx != ARMV8_PMU_CYCLE_IDX)
^
arch/arm64/kvm/sys_regs.c:564:27: note: each undeclared identifier is reported only once for each function it appears in
arch/arm64/kvm/sys_regs.c: In function 'access_pmu_evcntr':
arch/arm64/kvm/sys_regs.c:592:10: error: 'ARMV8_PMU_CYCLE_IDX' undeclared (first use in this function)
idx = ARMV8_PMU_CYCLE_IDX;
^
arch/arm64/kvm/sys_regs.c: In function 'access_pmu_evtyper':
arch/arm64/kvm/sys_regs.c:638:14: error: 'ARMV8_PMU_CYCLE_IDX' undeclared (first use in this function)
if (idx == ARMV8_PMU_CYCLE_IDX)
^
arch/arm64/kvm/hyp/switch.c:86:15: error: 'ARMV8_PMU_USERENR_MASK' undeclared (first use in this function)
write_sysreg(ARMV8_PMU_USERENR_MASK, pmuserenr_el0);
This patch fixes the build with CONFIG_ARM_PMU disabled.
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
We now store the mapped hardware IRQ number in our struct, so we
don't need the irq_phys_map for the new VGIC.
Implement the hardware IRQ mapping on top of the reworked arch
timer interface.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
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>
This patch implements the vgic_creation function which is
called on CREATE_IRQCHIP VM IOCTL (v2 only) or KVM_CREATE_DEVICE
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>
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>
In contrast to GICv2 SGIs in a GICv3 implementation are not triggered
by a MMIO write, but with a system register write. KVM knows about
that register already, we just need to implement the handler and wire
it up to the core KVM/ARM code.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Add an MMIO handling framework to the VGIC emulation:
Each register is described by its offset, size (or number of bits per
IRQ, if applicable) and the read/write handler functions. We provide
initialization macros to describe each GIC register later easily.
Separate dispatch functions for read and write accesses are connected
to the kvm_io_bus framework and binary-search for the responsible
register handler based on the offset address within the region.
We convert the incoming data (referenced by a pointer) to the host's
endianess and use pass-by-value to hand the data over to the actual
handler functions.
The register handler prototype and the endianess conversion are
courtesy of Christoffer Dall.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Tell KVM whether a particular VCPU has an IRQ that needs handling
in the guest. This is used to decide whether a VCPU is runnable.
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>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
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>
Add a new header file for the new and improved GIC implementation.
The big change is that we now have a struct vgic_irq per IRQ instead
of spreading all the information over various bitmaps.
We include this new header conditionally from within the old header
file for the time being to avoid touching all the users.
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Currently the PMU uses a member of the struct vgic_dist directly,
which not only breaks abstraction, but will fail with the new VGIC.
Abstract this access in the VGIC header file and refactor the validity
check in the PMU code.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
The number of list registers is a property of the underlying system, not
of emulated VGIC CPU interface.
As we are about to move this variable to global state in the new vgic
for clarity, move it from the legacy implementation as well to make the
merge of the new code easier.
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
We are about to modify the VGIC to allocate all data structures
dynamically and store mapped IRQ information on a per-IRQ struct, which
is indeed allocated dynamically at init time.
Therefore, we cannot record the mapped IRQ info from the timer at timer
reset time like it's done now, because VCPU reset happens before timer
init.
A possible later time to do this is on the first run of a per VCPU, it
just requires us to move the enable state to be a per-VCPU state and do
the lookup of the physical IRQ number when we are about to run the VCPU.
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Now that the virtual arch timer does not care about the irq_phys_map
anymore, let's rework kvm_vgic_map_phys_irq() to return an error
value instead. Any reference to that mapping can later be done by
passing the correct combination of VCPU and virtual IRQ number.
This makes the irq_phys_map handling completely private to the
VGIC code.
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>
Now that the interface between the arch timer and the VGIC does not
require passing the irq_phys_map entry pointer anymore, let's remove
it from the virtual arch timer and use the virtual IRQ number instead
directly.
The remaining pointer returned by kvm_vgic_map_phys_irq() will be
removed in the following patch.
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 communication of a Linux IRQ number from outside the VGIC to the
vgic was a leftover from the day when the vgic code cared about how a
particular device injects virtual interrupts mapped to a physical
interrupt.
We can safely remove this notion, leaving all physical IRQ handling to
be done in the device driver (the arch timer in this case), which makes
room for a saner API for the new VGIC.
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>
kvm_vgic_unmap_phys_irq() only needs the virtual IRQ number, so let's
just pass that between the arch timer and the VGIC to get rid of
the irq_phys_map pointer.
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>
For getting the active state of a mapped IRQ, we actually only need
the virtual IRQ number, not the pointer to the mapping entry.
Pass the virtual IRQ number from the arch timer to the VGIC directly.
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>
