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219 Commits

Author SHA1 Message Date
Paolo Bonzini 6f49b2f341 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.
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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.
2016-08-04 13:59:56 +02:00
Linus Torvalds 221bb8a46e - 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.
 
 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.
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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
  ...
2016-08-02 16:11:27 -04:00
Eric Auger 180ae7b118 KVM: arm/arm64: Enable irqchip routing
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>
2016-07-22 18:52:01 +01:00
Marc Zyngier bb7176449f KVM: arm64: vgic-its: Add pointer to corresponding kvm_device
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>
2016-07-18 18:15:18 +01:00
Andre Przywara 0e4e82f154 KVM: arm64: vgic-its: Enable ITS emulation as a virtual MSI controller
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>
2016-07-18 18:14:38 +01:00
Andre Przywara 3802411d01 KVM: arm64: vgic-its: Connect LPIs to the VGIC emulation
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>
2016-07-18 18:14:36 +01:00
Andre Przywara 424c33830f KVM: arm64: vgic-its: Implement basic ITS register handlers
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>
2016-07-18 18:14:36 +01:00
Andre Przywara 1085fdc68c KVM: arm64: vgic-its: Introduce new KVM ITS device
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>
2016-07-18 18:14:35 +01:00
Andre Przywara 59c5ab4098 KVM: arm64: vgic-its: Introduce ITS emulation file with MMIO framework
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>
2016-07-18 18:14:35 +01:00
Andre Przywara 0aa1de5731 KVM: arm64: vgic: Handle ITS related GICv3 redistributor registers
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>
2016-07-18 18:14:35 +01:00
Andre Przywara 5dd4b924e3 KVM: arm/arm64: vgic: Add refcounting for IRQs
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>
2016-07-18 18:10:48 +01:00
Andre Przywara 8f6cdc1c2e KVM: arm/arm64: vgic: Move redistributor kvm_io_devices
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>
2016-07-18 18:09:40 +01:00
Marc Zyngier 50926d82fa KVM: arm/arm64: The GIC is dead, long live the GIC
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>
2016-07-03 23:09:37 +02:00
Sudeep Holla 0efce9da12 arm64: KVM: fix build with CONFIG_ARM_PMU disabled
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>
2016-06-27 12:55:51 +02:00
Andre Przywara 568e8c901e KVM: arm/arm64: vgic-new: implement mapped IRQ handling
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>
2016-05-20 15:40:09 +02:00
Eric Auger b0442ee227 KVM: arm/arm64: vgic-new: vgic_init: implement map_resources
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>
2016-05-20 15:40:07 +02:00
Eric Auger ad275b8bb1 KVM: arm/arm64: vgic-new: vgic_init: implement vgic_init
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>
2016-05-20 15:40:06 +02:00
Eric Auger 5e6431da8f KVM: arm/arm64: vgic-new: vgic_init: implement vgic_create
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>
2016-05-20 15:40:06 +02:00
Eric Auger 9097773245 KVM: arm/arm64: vgic-new: vgic_init: implement kvm_vgic_hyp_init
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>
2016-05-20 15:40:05 +02:00
Eric Auger e2c1f9abff KVM: arm/arm64: vgic-new: vgic_kvm_device: implement kvm_vgic_addr
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>
2016-05-20 15:40:01 +02:00
Andre Przywara 621ecd8d21 KVM: arm/arm64: vgic-new: Add GICv3 SGI system register trap handler
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>
2016-05-20 15:39:59 +02:00
Marc Zyngier 4493b1c486 KVM: arm/arm64: vgic-new: Add MMIO handling framework
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>
2016-05-20 15:39:49 +02:00
Eric Auger 90eee56c5f KVM: arm/arm64: vgic-new: Implement kvm_vgic_vcpu_pending_irq
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>
2016-05-20 15:39:49 +02:00
Marc Zyngier 0919e84c0f KVM: arm/arm64: vgic-new: Add IRQ sync/flush framework
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>
2016-05-20 15:39:47 +02:00
Christoffer Dall 81eeb95ddb KVM: arm/arm64: vgic-new: Implement virtual IRQ injection
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>
2016-05-20 15:39:46 +02:00
Christoffer Dall b18b57787f KVM: arm/arm64: vgic-new: Add data structure definitions
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>
2016-05-20 15:39:45 +02:00
Andre Przywara 2defaff48a KVM: arm/arm64: pmu: abstract access to number of SPIs
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>
2016-05-20 15:39:43 +02:00
Christoffer Dall 2db4c104fa KVM: arm/arm64: Get rid of vgic_cpu->nr_lr
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>
2016-05-20 15:39:41 +02:00
Christoffer Dall 41a54482c0 KVM: arm/arm64: Move timer IRQ map to latest possible time
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>
2016-05-20 15:39:41 +02:00
Andre Przywara c8eb3f6b9b KVM: arm/arm64: vgic: Remove irq_phys_map from interface
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>
2016-05-20 15:39:40 +02:00
Andre Przywara a7e33ad9b2 KVM: arm/arm64: arch_timer: Remove irq_phys_map
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>
2016-05-20 15:39:39 +02:00
Christoffer Dall b452cb5207 KVM: arm/arm64: Remove the IRQ field from struct irq_phys_map
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>
2016-05-20 15:39:39 +02:00
Andre Przywara 63306c28ac KVM: arm/arm64: vgic: avoid map in kvm_vgic_unmap_phys_irq()
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>
2016-05-20 15:39:38 +02:00
Andre Przywara e262f41936 KVM: arm/arm64: vgic: avoid map in kvm_vgic_map_is_active()
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>
2016-05-20 15:39:38 +02:00
Andre Przywara 4f551a3d96 KVM: arm/arm64: vgic: avoid map in kvm_vgic_inject_mapped_irq()
When we want to inject a hardware mapped IRQ into a guest, we actually
only need the virtual IRQ number from the irq_phys_map.
So let's pass this number directly from the arch timer to the VGIC
to avoid using the map as a parameter.

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>
2016-05-20 15:39:37 +02:00
Julien Grall 503a62862e KVM: arm/arm64: vgic: Rely on the GIC driver to parse the firmware tables
Currently, the firmware tables are parsed 2 times: once in the GIC
drivers, the other time when initializing the vGIC. It means code
duplication and make more tedious to add the support for another
firmware table (like ACPI).

Use the recently introduced helper gic_get_kvm_info() to get
information about the virtual GIC.

With this change, the virtual GIC becomes agnostic to the firmware
table and KVM will be able to initialize the vGIC on ACPI.

Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-05-03 12:54:21 +02:00
Marc Zyngier 1b8e83c04e arm64: KVM: vgic-v3: Avoid accessing ICH registers
Just like on GICv2, we're a bit hammer-happy with GICv3, and access
them more often than we should.

Adopt a policy similar to what we do for GICv2, only save/restoring
the minimal set of registers. As we don't access the registers
linearly anymore (we may skip some), the convoluted accessors become
slightly simpler, and we can drop the ugly indexing macro that
tended to confuse the reviewers.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-03-09 04:24:04 +00:00
Marc Zyngier 59f00ff9af KVM: arm/arm64: vgic-v2: Avoid accessing GICH registers
GICv2 registers are *slow*. As in "terrifyingly slow". Which is bad.
But we're equaly bad, as we make a point in accessing them even if
we don't have any interrupt in flight.

A good solution is to first find out if we have anything useful to
write into the GIC, and if we don't, to simply not do it. This
involves tracking which LRs actually have something valid there.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-03-09 04:22:20 +00:00
Marc Zyngier 9b4a300443 KVM: arm/arm64: timer: Add active state caching
Programming the active state in the (re)distributor can be an
expensive operation so it makes some sense to try and reduce
the number of accesses as much as possible. So far, we
program the active state on each VM entry, but there is some
opportunity to do less.

An obvious solution is to cache the active state in memory,
and only program it in the HW when conditions change. But
because the HW can also change things under our feet (the active
state can transition from 1 to 0 when the guest does an EOI),
some precautions have to be taken, which amount to only caching
an "inactive" state, and always programing it otherwise.

With this in place, we observe a reduction of around 700 cycles
on a 2GHz GICv2 platform for a NULL hypercall.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:22 +00:00
Shannon Zhao bb0c70bcca arm64: KVM: Add a new vcpu device control group for PMUv3
To configure the virtual PMUv3 overflow interrupt number, we use the
vcpu kvm_device ioctl, encapsulating the KVM_ARM_VCPU_PMU_V3_IRQ
attribute within the KVM_ARM_VCPU_PMU_V3_CTRL group.

After configuring the PMUv3, call the vcpu ioctl with attribute
KVM_ARM_VCPU_PMU_V3_INIT to initialize the PMUv3.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Acked-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:21 +00:00
Shannon Zhao 808e738142 arm64: KVM: Add a new feature bit for PMUv3
To support guest PMUv3, use one bit of the VCPU INIT feature array.
Initialize the PMU when initialzing the vcpu with that bit and PMU
overflow interrupt set.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Acked-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:21 +00:00
Shannon Zhao 5f0a714a2b arm64: KVM: Free perf event of PMU when destroying vcpu
When KVM frees VCPU, it needs to free the perf_event of PMU.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:21 +00:00
Shannon Zhao 2aa36e9840 arm64: KVM: Reset PMU state when resetting vcpu
When resetting vcpu, it needs to reset the PMU state to initial status.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:21 +00:00
Shannon Zhao b02386eb7d arm64: KVM: Add PMU overflow interrupt routing
When calling perf_event_create_kernel_counter to create perf_event,
assign a overflow handler. Then when the perf event overflows, set the
corresponding bit of guest PMOVSSET register. If this counter is enabled
and its interrupt is enabled as well, kick the vcpu to sync the
interrupt.

On VM entry, if there is counter overflowed and interrupt level is
changed, inject the interrupt with corresponding level. On VM exit, sync
the interrupt level as well if it has been changed.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:21 +00:00
Shannon Zhao 76993739cd arm64: KVM: Add helper to handle PMCR register bits
According to ARMv8 spec, when writing 1 to PMCR.E, all counters are
enabled by PMCNTENSET, while writing 0 to PMCR.E, all counters are
disabled. When writing 1 to PMCR.P, reset all event counters, not
including PMCCNTR, to zero. When writing 1 to PMCR.C, reset PMCCNTR to
zero.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:21 +00:00
Shannon Zhao 7a0adc7064 arm64: KVM: Add access handler for PMSWINC register
Add access handler which emulates writing and reading PMSWINC
register and add support for creating software increment event.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:20 +00:00
Shannon Zhao 76d883c4e6 arm64: KVM: Add access handler for PMOVSSET and PMOVSCLR register
Since the reset value of PMOVSSET and PMOVSCLR is UNKNOWN, use
reset_unknown for its reset handler. Add a handler to emulate writing
PMOVSSET or PMOVSCLR register.

When writing non-zero value to PMOVSSET, the counter and its interrupt
is enabled, kick this vcpu to sync PMU interrupt.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:20 +00:00
Shannon Zhao 7f76635871 arm64: KVM: PMU: Add perf event map and introduce perf event creating function
When we use tools like perf on host, perf passes the event type and the
id of this event type category to kernel, then kernel will map them to
hardware event number and write this number to PMU PMEVTYPER<n>_EL0
register. When getting the event number in KVM, directly use raw event
type to create a perf_event for it.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:20 +00:00
Shannon Zhao 96b0eebcc6 arm64: KVM: Add access handler for PMCNTENSET and PMCNTENCLR register
Since the reset value of PMCNTENSET and PMCNTENCLR is UNKNOWN, use
reset_unknown for its reset handler. Add a handler to emulate writing
PMCNTENSET or PMCNTENCLR register.

When writing to PMCNTENSET, call perf_event_enable to enable the perf
event. When writing to PMCNTENCLR, call perf_event_disable to disable
the perf event.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:20 +00:00
Shannon Zhao 051ff581ce arm64: KVM: Add access handler for event counter register
These kind of registers include PMEVCNTRn, PMCCNTR and PMXEVCNTR which
is mapped to PMEVCNTRn.

The access handler translates all aarch32 register offsets to aarch64
ones and uses vcpu_sys_reg() to access their values to avoid taking care
of big endian.

When reading these registers, return the sum of register value and the
value perf event counts.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:20 +00:00
Shannon Zhao ab9468340d arm64: KVM: Add access handler for PMCR register
Add reset handler which gets host value of PMCR_EL0 and make writable
bits architecturally UNKNOWN except PMCR.E which is zero. Add an access
handler for PMCR.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:19 +00:00
Shannon Zhao 04fe472615 arm64: KVM: Define PMU data structure for each vcpu
Here we plan to support virtual PMU for guest by full software
emulation, so define some basic structs and functions preparing for
futher steps. Define struct kvm_pmc for performance monitor counter and
struct kvm_pmu for performance monitor unit for each vcpu. According to
ARMv8 spec, the PMU contains at most 32(ARMV8_PMU_MAX_COUNTERS)
counters.

Since this only supports ARM64 (or PMUv3), add a separate config symbol
for it.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:19 +00:00
Marc Zyngier 3c13b8f435 KVM: arm/arm64: vgic-v3: Make the LR indexing macro public
We store GICv3 LRs in reverse order so that the CPU can save/restore
them in rever order as well (don't ask why, the design is crazy),
and yet generate memory traffic that doesn't completely suck.

We need this macro to be available to the C version of save/restore.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-12-14 11:30:38 +00:00
Christoffer Dall 0e3dfda91d KVM: arm/arm64: arch_timer: Preserve physical dist. active state on LR.active
We were incorrectly removing the active state from the physical
distributor on the timer interrupt when the timer output level was
deasserted.  We shouldn't be doing this without considering the virtual
interrupt's active state, because the architecture requires that when an
LR has the HW bit set and the pending or active bits set, then the
physical interrupt must also have the corresponding bits set.

This addresses an issue where we have been observing an inconsistency
between the LR state and the physical distributor state where the LR
state was active and the physical distributor was not active, which
shouldn't happen.

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-11-24 18:07:40 +01:00
Linus Torvalds 933425fb00 s390: A bunch of fixes and optimizations for interrupt and time
handling.
 
 PPC: Mostly bug fixes.
 
 ARM: No big features, but many small fixes and prerequisites including:
 - a number of fixes for the arch-timer
 - introducing proper level-triggered semantics for the arch-timers
 - a series of patches to synchronously halt a guest (prerequisite for
   IRQ forwarding)
 - some tracepoint improvements
 - a tweak for the EL2 panic handlers
 - some more VGIC cleanups getting rid of redundant state
 
 x86: quite a few changes:
 
 - support for VT-d posted interrupts (i.e. PCI devices can inject
 interrupts directly into vCPUs).  This introduces a new component (in
 virt/lib/) that connects VFIO and KVM together.  The same infrastructure
 will be used for ARM interrupt forwarding as well.
 
 - more Hyper-V features, though the main one Hyper-V synthetic interrupt
 controller will have to wait for 4.5.  These will let KVM expose Hyper-V
 devices.
 
 - nested virtualization now supports VPID (same as PCID but for vCPUs)
 which makes it quite a bit faster
 
 - for future hardware that supports NVDIMM, there is support for clflushopt,
 clwb, pcommit
 
 - support for "split irqchip", i.e. LAPIC in kernel + IOAPIC/PIC/PIT in
 userspace, which reduces the attack surface of the hypervisor
 
 - obligatory smattering of SMM fixes
 
 - on the guest side, stable scheduler clock support was rewritten to not
 require help from the hypervisor.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "First batch of KVM changes for 4.4.

  s390:
     A bunch of fixes and optimizations for interrupt and time handling.

  PPC:
     Mostly bug fixes.

  ARM:
     No big features, but many small fixes and prerequisites including:

      - a number of fixes for the arch-timer

      - introducing proper level-triggered semantics for the arch-timers

      - a series of patches to synchronously halt a guest (prerequisite
        for IRQ forwarding)

      - some tracepoint improvements

      - a tweak for the EL2 panic handlers

      - some more VGIC cleanups getting rid of redundant state

  x86:
     Quite a few changes:

      - support for VT-d posted interrupts (i.e. PCI devices can inject
        interrupts directly into vCPUs).  This introduces a new
        component (in virt/lib/) that connects VFIO and KVM together.
        The same infrastructure will be used for ARM interrupt
        forwarding as well.

      - more Hyper-V features, though the main one Hyper-V synthetic
        interrupt controller will have to wait for 4.5.  These will let
        KVM expose Hyper-V devices.

      - nested virtualization now supports VPID (same as PCID but for
        vCPUs) which makes it quite a bit faster

      - for future hardware that supports NVDIMM, there is support for
        clflushopt, clwb, pcommit

      - support for "split irqchip", i.e.  LAPIC in kernel +
        IOAPIC/PIC/PIT in userspace, which reduces the attack surface of
        the hypervisor

      - obligatory smattering of SMM fixes

      - on the guest side, stable scheduler clock support was rewritten
        to not require help from the hypervisor"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (123 commits)
  KVM: VMX: Fix commit which broke PML
  KVM: x86: obey KVM_X86_QUIRK_CD_NW_CLEARED in kvm_set_cr0()
  KVM: x86: allow RSM from 64-bit mode
  KVM: VMX: fix SMEP and SMAP without EPT
  KVM: x86: move kvm_set_irq_inatomic to legacy device assignment
  KVM: device assignment: remove pointless #ifdefs
  KVM: x86: merge kvm_arch_set_irq with kvm_set_msi_inatomic
  KVM: x86: zero apic_arb_prio on reset
  drivers/hv: share Hyper-V SynIC constants with userspace
  KVM: x86: handle SMBASE as physical address in RSM
  KVM: x86: add read_phys to x86_emulate_ops
  KVM: x86: removing unused variable
  KVM: don't pointlessly leave KVM_COMPAT=y in non-KVM configs
  KVM: arm/arm64: Merge vgic_set_lr() and vgic_sync_lr_elrsr()
  KVM: arm/arm64: Clean up vgic_retire_lr() and surroundings
  KVM: arm/arm64: Optimize away redundant LR tracking
  KVM: s390: use simple switch statement as multiplexer
  KVM: s390: drop useless newline in debugging data
  KVM: s390: SCA must not cross page boundaries
  KVM: arm: Do not indent the arguments of DECLARE_BITMAP
  ...
2015-11-05 16:26:26 -08:00
Pavel Fedin 26caea7693 KVM: arm/arm64: Merge vgic_set_lr() and vgic_sync_lr_elrsr()
Now we see that vgic_set_lr() and vgic_sync_lr_elrsr() are always used
together. Merge them into one function, saving from second vgic_ops
dereferencing every time.

Signed-off-by: Pavel Fedin <p.fedin@samsung.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-11-04 15:29:49 +01:00
Pavel Fedin c4cd4c168b KVM: arm/arm64: Optimize away redundant LR tracking
Currently we use vgic_irq_lr_map in order to track which LRs hold which
IRQs, and lr_used bitmap in order to track which LRs are used or free.

vgic_irq_lr_map is actually used only for piggy-back optimization, and
can be easily replaced by iteration over lr_used. This is good because in
future, when LPI support is introduced, number of IRQs will grow up to at
least 16384, while numbers from 1024 to 8192 are never going to be used.
This would be a huge memory waste.

In its turn, lr_used is also completely redundant since
ae705930fc ("arm/arm64: KVM: Keep elrsr/aisr
in sync with software model"), because together with lr_used we also update
elrsr. This allows to easily replace lr_used with elrsr, inverting all
conditions (because in elrsr '1' means 'free').

Signed-off-by: Pavel Fedin <p.fedin@samsung.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-11-04 15:29:49 +01:00
Michal Marek 5fdf876d30 KVM: arm: Do not indent the arguments of DECLARE_BITMAP
Besides being a coding style issue, it confuses make tags:

ctags: Warning: include/kvm/arm_vgic.h:307: null expansion of name pattern "\1"
ctags: Warning: include/kvm/arm_vgic.h:308: null expansion of name pattern "\1"
ctags: Warning: include/kvm/arm_vgic.h:309: null expansion of name pattern "\1"
ctags: Warning: include/kvm/arm_vgic.h:317: null expansion of name pattern "\1"

Cc: kvmarm@lists.cs.columbia.edu
Signed-off-by: Michal Marek <mmarek@suse.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-10-22 23:01:49 +02:00
Christoffer Dall 4b4b4512da arm/arm64: KVM: Rework the arch timer to use level-triggered semantics
The arch timer currently uses edge-triggered semantics in the sense that
the line is never sampled by the vgic and lowering the line from the
timer to the vgic doesn't have any effect on the pending state of
virtual interrupts in the vgic.  This means that we do not support a
guest with the otherwise valid behavior of (1) disable interrupts (2)
enable the timer (3) disable the timer (4) enable interrupts.  Such a
guest would validly not expect to see any interrupts on real hardware,
but will see interrupts on KVM.

This patch fixes this shortcoming through the following series of
changes.

First, we change the flow of the timer/vgic sync/flush operations.  Now
the timer is always flushed/synced before the vgic, because the vgic
samples the state of the timer output.  This has the implication that we
move the timer operations in to non-preempible sections, but that is
fine after the previous commit getting rid of hrtimer schedules on every
entry/exit.

Second, we change the internal behavior of the timer, letting the timer
keep track of its previous output state, and only lower/raise the line
to the vgic when the state changes.  Note that in theory this could have
been accomplished more simply by signalling the vgic every time the
state *potentially* changed, but we don't want to be hitting the vgic
more often than necessary.

Third, we get rid of the use of the map->active field in the vgic and
instead simply set the interrupt as active on the physical distributor
whenever the input to the GIC is asserted and conversely clear the
physical active state when the input to the GIC is deasserted.

Fourth, and finally, we now initialize the timer PPIs (and all the other
unused PPIs for now), to be level-triggered, and modify the sync code to
sample the line state on HW sync and re-inject a new interrupt if it is
still pending at that time.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-10-22 23:01:44 +02:00
Christoffer Dall d35268da66 arm/arm64: KVM: arch_timer: Only schedule soft timer on vcpu_block
We currently schedule a soft timer every time we exit the guest if the
timer did not expire while running the guest.  This is really not
necessary, because the only work we do in the timer work function is to
kick the vcpu.

Kicking the vcpu does two things:
(1) If the vpcu thread is on a waitqueue, make it runnable and remove it
from the waitqueue.
(2) If the vcpu is running on a different physical CPU from the one
doing the kick, it sends a reschedule IPI.

The second case cannot happen, because the soft timer is only ever
scheduled when the vcpu is not running.  The first case is only relevant
when the vcpu thread is on a waitqueue, which is only the case when the
vcpu thread has called kvm_vcpu_block().

Therefore, we only need to make sure a timer is scheduled for
kvm_vcpu_block(), which we do by encapsulating all calls to
kvm_vcpu_block() with kvm_timer_{un}schedule calls.

Additionally, we only schedule a soft timer if the timer is enabled and
unmasked, since it is useless otherwise.

Note that theoretically userspace can use the SET_ONE_REG interface to
change registers that should cause the timer to fire, even if the vcpu
is blocked without a scheduled timer, but this case was not supported
before this patch and we leave it for future work for now.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-10-22 23:01:42 +02:00
Jean-Philippe Brucker 4f64cb65bf arm/arm64: KVM: Only allow 64bit hosts to build VGICv3
Hardware virtualisation of GICv3 is only supported by 64bit hosts for
the moment. Some VGICv3 bits are missing from the 32bit side, and this
patch allows to still be able to build 32bit hosts when CONFIG_ARM_GIC_V3
is selected.

To this end, we introduce a new option, CONFIG_KVM_ARM_VGIC_V3, that is
only enabled on the 64bit side. The selection is done unconditionally
because CONFIG_ARM_GIC_V3 is always enabled on arm64.

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-10-09 23:11:57 +01:00
Ming Lei ef748917b5 arm/arm64: KVM: Remove 'config KVM_ARM_MAX_VCPUS'
This patch removes config option of KVM_ARM_MAX_VCPUS,
and like other ARCHs, just choose the maximum allowed
value from hardware, and follows the reasons:

1) from distribution view, the option has to be
defined as the max allowed value because it need to
meet all kinds of virtulization applications and
need to support most of SoCs;

2) using a bigger value doesn't introduce extra memory
consumption, and the help text in Kconfig isn't accurate
because kvm_vpu structure isn't allocated until request
of creating VCPU is sent from QEMU;

3) the main effect is that the field of vcpus[] in 'struct kvm'
becomes a bit bigger(sizeof(void *) per vcpu) and need more cache
lines to hold the structure, but 'struct kvm' is one generic struct,
and it has worked well on other ARCHs already in this way. Also,
the world switch frequecy is often low, for example, it is ~2000
when running kernel building load in VM from APM xgene KVM host,
so the effect is very small, and the difference can't be observed
in my test at all.

Cc: Dann Frazier <dann.frazier@canonical.com>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-09-17 13:13:27 +01:00
Marc Zyngier f120cd6533 KVM: arm/arm64: timer: Allow the timer to control the active state
In order to remove the crude hack where we sneak the masked bit
into the timer's control register, make use of the phys_irq_map
API control the active state of the interrupt.

This causes some limited changes to allow for potential error
propagation.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-08-12 11:28:26 +01:00
Marc Zyngier 773299a570 KVM: arm/arm64: vgic: Prevent userspace injection of a mapped interrupt
Virtual interrupts mapped to a HW interrupt should only be triggered
from inside the kernel. Otherwise, you could end up confusing the
kernel (and the GIC's) state machine.

Rearrange the injection path so that kvm_vgic_inject_irq is
used for non-mapped interrupts, and kvm_vgic_inject_mapped_irq is
used for mapped interrupts. The latter should only be called from
inside the kernel (timer, irqfd).

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-08-12 11:28:26 +01:00
Marc Zyngier 6e84e0e067 KVM: arm/arm64: vgic: Add vgic_{get,set}_phys_irq_active
In order to control the active state of an interrupt, introduce
a pair of accessors allowing the state to be set/queried.

This only affects the logical state, and the HW state will only be
applied at world-switch time.

Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-08-12 11:28:26 +01:00
Marc Zyngier 6c3d63c9a2 KVM: arm/arm64: vgic: Allow dynamic mapping of physical/virtual interrupts
In order to be able to feed physical interrupts to a guest, we need
to be able to establish the virtual-physical mapping between the two
worlds.

The mappings are kept in a set of RCU lists, indexed by virtual interrupts.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-08-12 11:28:25 +01:00
Marc Zyngier 32d2d8010c KVM: arm/arm64: vgic: Convert struct vgic_lr to use bitfields
As we're about to cram more information in the vgic_lr structure
(HW interrupt number and additional state information), we switch
to a layout similar to the HW's:

- use bitfields to save space (we don't need more than 10 bits
  to represent the irq numbers)
- source CPU and HW interrupt can share the same field, as
  a SGI doesn't have a physical line.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-08-12 11:28:24 +01:00
Paolo Bonzini bf0fb67cf9 KVM/ARM changes for v4.1:
- fixes for live migration
 - irqfd support
 - kvm-io-bus & vgic rework to enable ioeventfd
 - page ageing for stage-2 translation
 - various cleanups
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Merge tag 'kvm-arm-for-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into 'kvm-next'

KVM/ARM changes for v4.1:

- fixes for live migration
- irqfd support
- kvm-io-bus & vgic rework to enable ioeventfd
- page ageing for stage-2 translation
- various cleanups
2015-04-07 18:09:20 +02:00
Andre Przywara 950324ab81 KVM: arm/arm64: rework MMIO abort handling to use KVM MMIO bus
Currently we have struct kvm_exit_mmio for encapsulating MMIO abort
data to be passed on from syndrome decoding all the way down to the
VGIC register handlers. Now as we switch the MMIO handling to be
routed through the KVM MMIO bus, it does not make sense anymore to
use that structure already from the beginning. So we keep the data in
local variables until we put them into the kvm_io_bus framework.
Then we fill kvm_exit_mmio in the VGIC only, making it a VGIC private
structure. On that way we replace the data buffer in that structure
with a pointer pointing to a single location in a local variable, so
we get rid of some copying on the way.
With all of the virtual GIC emulation code now being registered with
the kvm_io_bus, we can remove all of the old MMIO handling code and
its dispatching functionality.

I didn't bother to rename kvm_exit_mmio (to vgic_mmio or something),
because that touches a lot of code lines without any good reason.

This is based on an original patch by Nikolay.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Cc: Nikolay Nikolaev <n.nikolaev@virtualopensystems.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-03-30 17:07:19 +01:00
Andre Przywara fb8f61abab KVM: arm/arm64: prepare GICv3 emulation to use kvm_io_bus MMIO handling
Using the framework provided by the recent vgic.c changes, we
register a kvm_io_bus device on mapping the virtual GICv3 resources.
The distributor mapping is pretty straight forward, but the
redistributors need some more love, since they need to be tagged with
the respective redistributor (read: VCPU) they are connected with.
We use the kvm_io_bus framework to register one devices per VCPU.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-03-30 17:07:13 +01:00
Andre Przywara a9cf86f62b KVM: arm/arm64: prepare GICv2 emulation to be handled by kvm_io_bus
Using the framework provided by the recent vgic.c changes we register
a kvm_io_bus device when initializing the virtual GICv2.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-03-26 21:43:15 +00:00
Andre Przywara 6777f77f0f KVM: arm/arm64: implement kvm_io_bus MMIO handling for the VGIC
Currently we use a lot of VGIC specific code to do the MMIO
dispatching.
Use the previous reworks to add kvm_io_bus style MMIO handlers.

Those are not yet called by the MMIO abort handler, also the actual
VGIC emulator function do not make use of it yet, but will be enabled
with the following patches.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-03-26 21:43:14 +00:00
Andre Przywara af669ac6dc KVM: move iodev.h from virt/kvm/ to include/kvm
iodev.h contains definitions for the kvm_io_bus framework. This is
needed both by the generic KVM code in virt/kvm as well as by
architecture specific code under arch/. Putting the header file in
virt/kvm and using local includes in the architecture part seems at
least dodgy to me, so let's move the file into include/kvm, so that a
more natural "#include <kvm/iodev.h>" can be used by all of the code.
This also solves a problem later when using struct kvm_io_device
in arm_vgic.h.
Fixing up the FSF address in the GPL header and a wrong include path
on the way.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-03-26 21:43:12 +00:00
Christoffer Dall 1a74847885 arm/arm64: KVM: Fix migration race in the arch timer
When a VCPU is no longer running, we currently check to see if it has a
timer scheduled in the future, and if it does, we schedule a host
hrtimer to notify is in case the timer expires while the VCPU is still
not running.  When the hrtimer fires, we mask the guest's timer and
inject the timer IRQ (still relying on the guest unmasking the time when
it receives the IRQ).

This is all good and fine, but when migration a VM (checkpoint/restore)
this introduces a race.  It is unlikely, but possible, for the following
sequence of events to happen:

 1. Userspace stops the VM
 2. Hrtimer for VCPU is scheduled
 3. Userspace checkpoints the VGIC state (no pending timer interrupts)
 4. The hrtimer fires, schedules work in a workqueue
 5. Workqueue function runs, masks the timer and injects timer interrupt
 6. Userspace checkpoints the timer state (timer masked)

At restore time, you end up with a masked timer without any timer
interrupts and your guest halts never receiving timer interrupts.

Fix this by only kicking the VCPU in the workqueue function, and sample
the expired state of the timer when entering the guest again and inject
the interrupt and mask the timer only then.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-03-14 13:48:00 +01:00
Christoffer Dall 47a98b15ba arm/arm64: KVM: support for un-queuing active IRQs
Migrating active interrupts causes the active state to be lost
completely. This implements some additional bitmaps to track the active
state on the distributor and export this to user space.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-03-14 13:46:44 +01:00
Christoffer Dall ae705930fc arm/arm64: KVM: Keep elrsr/aisr in sync with software model
There is an interesting bug in the vgic code, which manifests itself
when the KVM run loop has a signal pending or needs a vmid generation
rollover after having disabled interrupts but before actually switching
to the guest.

In this case, we flush the vgic as usual, but we sync back the vgic
state and exit to userspace before entering the guest.  The consequence
is that we will be syncing the list registers back to the software model
using the GICH_ELRSR and GICH_EISR from the last execution of the guest,
potentially overwriting a list register containing an interrupt.

This showed up during migration testing where we would capture a state
where the VM has masked the arch timer but there were no interrupts,
resulting in a hung test.

Cc: Marc Zyngier <marc.zyngier@arm.com>
Reported-by: Alex Bennee <alex.bennee@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-03-14 13:42:07 +01:00
Christoffer Dall 662d971584 arm/arm64: KVM: Kill CONFIG_KVM_ARM_{VGIC,TIMER}
We can definitely decide at run-time whether to use the GIC and timers
or not, and the extra code and data structures that we allocate space
for is really negligable with this config option, so I don't think it's
worth the extra complexity of always having to define stub static
inlines.  The !CONFIG_KVM_ARM_VGIC/TIMER case is pretty much an untested
code path anyway, so we're better off just getting rid of it.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
2015-03-12 15:15:27 +01:00
Andre Przywara ac3d373564 arm/arm64: KVM: allow userland to request a virtual GICv3
With all of the GICv3 code in place now we allow userland to ask the
kernel for using a virtual GICv3 in the guest.
Also we provide the necessary support for guests setting the memory
addresses for the virtual distributor and redistributors.
This requires some userland code to make use of that feature and
explicitly ask for a virtual GICv3.
Document that KVM_CREATE_IRQCHIP only works for GICv2, but is
considered legacy and using KVM_CREATE_DEVICE is preferred.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-01-20 18:25:33 +01:00
Andre Przywara b5d84ff600 arm/arm64: KVM: enable kernel side of GICv3 emulation
With all the necessary GICv3 emulation code in place, we can now
connect the code to the GICv3 backend in the kernel.
The LR register handling is different depending on the emulated GIC
model, so provide different implementations for each.
Also allow non-v2-compatible GICv3 implementations (which don't
provide MMIO regions for the virtual CPU interface in the DT), but
restrict those hosts to support GICv3 guests only.
If the device tree provides a GICv2 compatible GICV resource entry,
but that one is faulty, just disable the GICv2 emulation and let the
user use at least the GICv3 emulation for guests.
To provide proper support for the legacy KVM_CREATE_IRQCHIP ioctl,
note virtual GICv2 compatibility in struct vgic_params and use it
on creating a VGICv2.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-01-20 18:25:32 +01:00
Andre Przywara 6d52f35af1 arm64: KVM: add SGI generation register emulation
While the generation of a (virtual) inter-processor interrupt (SGI)
on a GICv2 works by writing to a MMIO register, GICv3 uses the system
register ICC_SGI1R_EL1 to trigger them.
Add a trap handler function that calls the new SGI register handler
in the GICv3 code. As ICC_SRE_EL1.SRE at this point is still always 0,
this will not trap yet, but will only be used later when all the data
structures have been initialized properly.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-01-20 18:25:32 +01:00
Andre Przywara a0675c25d6 arm/arm64: KVM: add virtual GICv3 distributor emulation
With everything separated and prepared, we implement a model of a
GICv3 distributor and redistributors by using the existing framework
to provide handler functions for each register group.

Currently we limit the emulation to a model enforcing a single
security state, with SRE==1 (forcing system register access) and
ARE==1 (allowing more than 8 VCPUs).

We share some of the functions provided for GICv2 emulation, but take
the different ways of addressing (v)CPUs into account.
Save and restore is currently not implemented.

Similar to the split-off of the GICv2 specific code, the new emulation
code goes into a new file (vgic-v3-emul.c).

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-01-20 18:25:31 +01:00
Andre Przywara 2f5fa41a7a arm/arm64: KVM: make the value of ICC_SRE_EL1 a per-VM variable
ICC_SRE_EL1 is a system register allowing msr/mrs accesses to the
GIC CPU interface for EL1 (guests). Currently we force it to 0, but
for proper GICv3 support we have to allow guests to use it (depending
on their selected virtual GIC model).
So add ICC_SRE_EL1 to the list of saved/restored registers on a
world switch, but actually disallow a guest to change it by only
restoring a fixed, once-initialized value.
This value depends on the GIC model userland has chosen for a guest.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-01-20 18:25:28 +01:00
Andre Przywara 3caa2d8c3b arm/arm64: KVM: make the maximum number of vCPUs a per-VM value
Currently the maximum number of vCPUs supported is a global value
limited by the used GIC model. GICv3 will lift this limit, but we
still need to observe it for guests using GICv2.
So the maximum number of vCPUs is per-VM value, depending on the
GIC model the guest uses.
Store and check the value in struct kvm_arch, but keep it down to
8 for now.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-01-20 18:25:28 +01:00
Andre Przywara b26e5fdac4 arm/arm64: KVM: introduce per-VM ops
Currently we only have one virtual GIC model supported, so all guests
use the same emulation code. With the addition of another model we
end up with different guests using potentially different vGIC models,
so we have to split up some functions to be per VM.
Introduce a vgic_vm_ops struct to hold function pointers for those
functions that are different and provide the necessary code to
initialize them.
Also split up the vgic_init() function to separate out VGIC model
specific functionality into a separate function, which will later be
different for a GICv3 model.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-01-20 18:25:26 +01:00
Andre Przywara 59892136c4 arm/arm64: KVM: pass down user space provided GIC type into vGIC code
With the introduction of a second emulated GIC model we need to let
userspace specify the GIC model to use for each VM. Pass the
userspace provided value down into the vGIC code and store it there
to differentiate later.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-01-20 18:25:25 +01:00
Christoffer Dall 05971120fc arm/arm64: KVM: Require in-kernel vgic for the arch timers
It is curently possible to run a VM with architected timers support
without creating an in-kernel VGIC, which will result in interrupts from
the virtual timer going nowhere.

To address this issue, move the architected timers initialization to the
time when we run a VCPU for the first time, and then only initialize
(and enable) the architected timers if we have a properly created and
initialized in-kernel VGIC.

When injecting interrupts from the virtual timer to the vgic, the
current setup should ensure that this never calls an on-demand init of
the VGIC, which is the only call path that could return an error from
kvm_vgic_inject_irq(), so capture the return value and raise a warning
if there's an error there.

We also change the kvm_timer_init() function from returning an int to be
a void function, since the function always succeeds.

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-12-15 11:50:42 +01:00
Christoffer Dall 1f57be2895 arm/arm64: KVM: Add (new) vgic_initialized macro
Some code paths will need to check to see if the internal state of the
vgic has been initialized (such as when creating new VCPUs), so
introduce such a macro that checks the nr_cpus field which is set when
the vgic has been initialized.

Also set nr_cpus = 0 in kvm_vgic_destroy, because the error path in
vgic_init() will call this function, and code should never errornously
assume the vgic to be properly initialized after an error.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-12-13 14:17:10 +01:00
Christoffer Dall c52edf5f8c arm/arm64: KVM: Rename vgic_initialized to vgic_ready
The vgic_initialized() macro currently returns the state of the
vgic->ready flag, which indicates if the vgic is ready to be used when
running a VM, not specifically if its internal state has been
initialized.

Rename the macro accordingly in preparation for a more nuanced
initialization flow.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-12-13 14:17:05 +01:00
Peter Maydell 6d3cfbe21b arm/arm64: KVM: vgic: move reset initialization into vgic_init_maps()
VGIC initialization currently happens in three phases:
 (1) kvm_vgic_create() (triggered by userspace GIC creation)
 (2) vgic_init_maps() (triggered by userspace GIC register read/write
     requests, or from kvm_vgic_init() if not already run)
 (3) kvm_vgic_init() (triggered by first VM run)

We were doing initialization of some state to correspond with the
state of a freshly-reset GIC in kvm_vgic_init(); this is too late,
since it will overwrite changes made by userspace using the
register access APIs before the VM is run. Move this initialization
earlier, into the vgic_init_maps() phase.

This fixes a bug where QEMU could successfully restore a saved
VM state snapshot into a VM that had already been run, but could
not restore it "from cold" using the -loadvm command line option
(the symptoms being that the restored VM would run but interrupts
were ignored).

Finally rename vgic_init_maps to vgic_init and renamed kvm_vgic_init to
kvm_vgic_map_resources.

  [ This patch is originally written by Peter Maydell, but I have
    modified it somewhat heavily, renaming various bits and moving code
    around.  If something is broken, I am to be blamed. - Christoffer ]

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-12-13 14:15:52 +01:00
Christoffer Dall 2df36a5dd6 arm/arm64: KVM: Fix BE accesses to GICv2 EISR and ELRSR regs
The EIRSR and ELRSR registers are 32-bit registers on GICv2, and we
store these as an array of two such registers on the vgic vcpu struct.
However, we access them as a single 64-bit value or as a bitmap pointer
in the generic vgic code, which breaks BE support.

Instead, store them as u64 values on the vgic structure and do the
word-swapping in the assembly code, which already handles the byte order
for BE systems.

Tested-by: Victor Kamensky <victor.kamensky@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-10-16 10:57:41 +02:00
Arnd Bergmann b5e7a955a3 ARM: KVM: fix vgic-disabled build
The vgic code can be disabled in Kconfig and there are dummy implementations
of most of the provided API functions for the disabled case.

However, the newly introduced kvm_vgic_destroy/kvm_vgic_vcpu_destroy
functions are lacking those dummies, resulting in this build error:

arch/arm/kvm/arm.c: In function 'kvm_arch_destroy_vm':
arch/arm/kvm/arm.c:165:2: error: implicit declaration of function 'kvm_vgic_destroy' [-Werror=implicit-function-declaration]
  kvm_vgic_destroy(kvm);
  ^
arch/arm/kvm/arm.c: In function 'kvm_arch_vcpu_free':
arch/arm/kvm/arm.c:248:2: error: implicit declaration of function 'kvm_vgic_vcpu_destroy' [-Werror=implicit-function-declaration]
  kvm_vgic_vcpu_destroy(vcpu);
  ^

This adds two inline helpers to get it to build again in this configuration.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: c1bfb577ad ("arm/arm64: KVM: vgic: switch to dynamic allocation")
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-10-07 12:30:16 +02:00
Marc Zyngier 4956f2bc1f arm/arm64: KVM: vgic: delay vgic allocation until init time
It is now quite easy to delay the allocation of the vgic tables
until we actually require it to be up and running (when the first
vcpu is kicking around, or someones tries to access the GIC registers).

This allow us to allocate memory for the exact number of CPUs we
have. As nobody configures the number of interrupts just yet,
use a fallback to VGIC_NR_IRQS_LEGACY.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2014-09-18 18:48:58 -07:00
Marc Zyngier 5fb66da640 arm/arm64: KVM: vgic: kill VGIC_NR_IRQS
Nuke VGIC_NR_IRQS entierly, now that the distributor instance
contains the number of IRQ allocated to this GIC.

Also add VGIC_NR_IRQS_LEGACY to preserve the current API.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2014-09-18 18:48:57 -07:00
Marc Zyngier c3c918361a arm/arm64: KVM: vgic: handle out-of-range MMIO accesses
Now that we can (almost) dynamically size the number of interrupts,
we're facing an interesting issue:

We have to evaluate at runtime whether or not an access hits a valid
register, based on the sizing of this particular instance of the
distributor. Furthermore, the GIC spec says that accessing a reserved
register is RAZ/WI.

For this, add a new field to our range structure, indicating the number
of bits a single interrupts uses. That allows us to find out whether or
not the access is in range.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2014-09-18 18:48:57 -07:00
Marc Zyngier fc675e355e arm/arm64: KVM: vgic: kill VGIC_MAX_CPUS
We now have the information about the number of CPU interfaces in
the distributor itself. Let's get rid of VGIC_MAX_CPUS, and just
rely on KVM_MAX_VCPUS where we don't have the choice. Yet.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2014-09-18 18:48:57 -07:00
Marc Zyngier fb65ab63b8 arm/arm64: KVM: vgic: Parametrize VGIC_NR_SHARED_IRQS
Having a dynamic number of supported interrupts means that we
cannot relly on VGIC_NR_SHARED_IRQS being fixed anymore.

Instead, make it take the distributor structure as a parameter,
so it can return the right value.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2014-09-18 18:48:56 -07:00
Marc Zyngier c1bfb577ad arm/arm64: KVM: vgic: switch to dynamic allocation
So far, all the VGIC data structures are statically defined by the
*maximum* number of vcpus and interrupts it supports. It means that
we always have to oversize it to cater for the worse case.

Start by changing the data structures to be dynamically sizeable,
and allocate them at runtime.

The sizes are still very static though.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2014-09-18 18:48:52 -07:00
Christoffer Dall faa1b46c3e arm/arm64: KVM: vgic: Improve handling of GICD_I{CS}PENDRn
Writes to GICD_ISPENDRn and GICD_ICPENDRn are currently not handled
correctly for level-triggered interrupts.  The spec states that for
level-triggered interrupts, writes to the GICD_ISPENDRn activate the
output of a flip-flop which is in turn or'ed with the actual input
interrupt signal.  Correspondingly, writes to GICD_ICPENDRn simply
deactivates the output of that flip-flop, but does not (of course) affect
the external input signal.  Reads from GICC_IAR will also deactivate the
flip-flop output.

This requires us to track the state of the level-input separately from
the state in the flip-flop.  We therefore introduce two new variables on
the distributor struct to track these two states.  Astute readers may
notice that this is introducing more state than required (because an OR
of the two states gives you the pending state), but the remaining vgic
code uses the pending bitmap for optimized operations to figure out, at
the end of the day, if an interrupt is pending or not on the distributor
side.  Refactoring the code to consider the two state variables all the
places where we currently access the precomputed pending value, did not
look pretty.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-09-18 18:44:31 -07:00
Christoffer Dall dbf20f9d81 arm/arm64: KVM: Rename irq_active to irq_queued
We have a special bitmap on the distributor struct to keep track of when
level-triggered interrupts are queued on the list registers.  This was
named irq_active, which is confusing, because the active state of an
interrupt as per the GIC spec is a different thing, not specifically
related to edge-triggered/level-triggered configurations but rather
indicates an interrupt which has been ack'ed but not yet eoi'ed.

Rename the bitmap and the corresponding accessor functions to irq_queued
to clarify what this is actually used for.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-09-18 18:44:30 -07:00
Christoffer Dall 227844f538 arm/arm64: KVM: Rename irq_state to irq_pending
The irq_state field on the distributor struct is ambiguous in its
meaning; the comment says it's the level of the input put, but that
doesn't make much sense for edge-triggered interrupts.  The code
actually uses this state variable to check if the interrupt is in the
pending state on the distributor so clarify the comment and rename the
actual variable and accessor methods.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-09-18 18:44:30 -07:00
Marc Zyngier b2fb1c0d37 KVM: ARM: vgic: add the GICv3 backend
Introduce the support code for emulating a GICv2 on top of GICv3
hardware.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2014-07-11 04:57:36 -07:00
Marc Zyngier 1a9b13056d arm64: KVM: split GICv2 world switch from hyp code
Move the GICv2 world switch code into its own file, and add the
necessary indirection to the arm64 switch code.

Also introduce a new type field to the vgic_params structure.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2014-07-11 04:57:36 -07:00
Marc Zyngier f982cf4e9c KVM: ARM: vgic: revisit implementation of irqchip_in_kernel
So far, irqchip_in_kernel() was implemented by testing the value of
vctrl_base, which worked fine with GICv2.

With GICv3, this field is useless, as we're using system registers
instead of a emmory mapped interface. To solve this, add a boolean
flag indicating if the we're using a vgic or not.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2014-07-11 04:57:35 -07:00
Marc Zyngier 8f186d522c KVM: ARM: vgic: split GICv2 backend from the main vgic code
Brutally hack the innocent vgic code, and move the GICv2 specific code
to its own file, using vgic_ops and vgic_params as a way to pass
information between the two blocks.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2014-07-11 04:57:34 -07:00
Marc Zyngier ca85f623e3 KVM: ARM: introduce vgic_params structure
Move all the data specific to a given GIC implementation into its own
little structure.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2014-07-11 04:57:34 -07:00
Marc Zyngier da8dafd177 KVM: ARM: vgic: introduce vgic_enable
Move the code dealing with enabling the VGIC on to vgic_ops.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2014-07-11 04:57:33 -07:00
Marc Zyngier beee38b9d0 KVM: ARM: vgic: abstract VMCR access
Instead of directly messing with with the GICH_VMCR bits for the CPU
interface save/restore code, add accessors that encode/decode the
entire set of registers exposed by VMCR.

Not the most efficient thing, but given that this code is only used
by the save/restore code, performance is far from being critical.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2014-07-11 04:57:33 -07:00
Marc Zyngier 909d9b5025 KVM: ARM: vgic: move underflow handling to vgic_ops
Move the code dealing with LR underflow handling to its own functions,
and make them accessible through vgic_ops.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2014-07-11 04:57:33 -07:00
Marc Zyngier 495dd859f3 KVM: ARM: vgic: abstract MISR decoding
Instead of directly dealing with the GICH_MISR bits, move the code to
its own function and use a couple of public flags to represent the
actual state.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2014-07-11 04:57:32 -07:00
Marc Zyngier 8d6a0313c1 KVM: ARM: vgic: abstract EISR bitmap access
Move the GICH_EISR access to its own function.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2014-07-11 04:57:32 -07:00
Marc Zyngier 69bb2c9fbc KVM: ARM: vgic: abstract access to the ELRSR bitmap
Move the GICH_ELRSR access to its own functions, and add them to
the vgic_ops structure.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2014-07-11 04:57:31 -07:00
Marc Zyngier 8d5c6b06a5 KVM: ARM: vgic: introduce vgic_ops and LR manipulation primitives
In order to split the various register manipulation from the main vgic
code, introduce a vgic_ops structure, and start by abstracting the
LR manipulation code with a couple of accessors.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2014-07-11 04:57:31 -07:00
Marc Zyngier eede821dbf KVM: arm/arm64: vgic: move GICv2 registers to their own structure
In order to make way for the GICv3 registers, move the v2-specific
registers to their own structure.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2014-07-11 04:57:31 -07:00
Alex Bennée 1df08ba0aa arm64: KVM: allow export and import of generic timer regs
For correct guest suspend/resume behaviour we need to ensure we include
the generic timer registers for 64 bit guests. As CONFIG_KVM_ARM_TIMER is
always set for arm64 we don't need to worry about null implementations.
However I have re-jigged the kvm_arm_timer_set/get_reg declarations to
be in the common include/kvm/arm_arch_timer.h headers.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-07-11 04:46:55 -07:00
Marc Zyngier 6cbde8253a ARM: KVM: fix non-VGIC compilation
Add a stub for kvm_vgic_addr when compiling without
CONFIG_KVM_ARM_VGIC. The usefulness of this configurarion is extremely
doubtful, but let's fix it anyway (until we decide that we'll always
support a VGIC).

Reported-by: Michele Paolino <m.paolino@virtualopensystems.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-03-06 09:47:42 +01:00
Christoffer Dall ce01e4e887 KVM: arm-vgic: Set base addr through device API
Support setting the distributor and cpu interface base addresses in the
VM physical address space through the KVM_{SET,GET}_DEVICE_ATTR API
in addition to the ARM specific API.

This has the added benefit of being able to share more code in user
space and do things in a uniform manner.

Also deprecate the older API at the same time, but backwards
compatibility will be maintained.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2013-12-21 10:01:22 -08:00
Christoffer Dall 9b2d2e0df8 ARM: KVM: vgic: Bump VGIC_NR_IRQS to 256
The Versatile Express TC2 board, which we use as our main emulated
platform in QEMU, defines 160+32 == 192 interrupts, so limiting the
number of interrupts to 128 is not quite going to cut it for real board
emulation.

Note that this didn't use to be a problem because QEMU was buggy and
only defined 128 interrupts until recently.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-08-30 16:12:39 +03:00
Anup Patel 5ae7f87a56 ARM: KVM: Allow host virt timer irq to be different from guest timer virt irq
The arch_timer irq numbers (or PPI numbers) are implementation dependent,
so the host virtual timer irq number can be different from guest virtual
timer irq number.

This patch ensures that host virtual timer irq number is read from DTB and
guest virtual timer irq is determined based on vcpu target type.

Signed-off-by: Anup Patel <anup.patel@linaro.org>
Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org>
Signed-off-by: Christoffer Dall <cdall@cs.columbia.edu>
2013-06-26 10:50:02 -07:00
Marc Zyngier 7275acdfe2 ARM: KVM: move GIC/timer code to a common location
As KVM/arm64 is looming on the horizon, it makes sense to move some
of the common code to a single location in order to reduce duplication.

The code could live anywhere. Actually, most of KVM is already built
with a bunch of ugly ../../.. hacks in the various Makefiles, so we're
not exactly talking about style here. But maybe it is time to start
moving into a less ugly direction.

The include files must be in a "public" location, as they are accessed
from non-KVM files (arch/arm/kernel/asm-offsets.c).

For this purpose, introduce two new locations:
- virt/kvm/arm/ : x86 and ia64 already share the ioapic code in
  virt/kvm, so this could be seen as a (very ugly) precedent.
- include/kvm/  : there is already an include/xen, and while the
  intent is slightly different, this seems as good a location as
  any

Eventually, we should probably have independant Makefiles at every
levels (just like everywhere else in the kernel), but this is just
the first step.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-19 15:13:08 +03:00