Commit graph

1082 commits

Author SHA1 Message Date
Andre Przywara df9f58fbea KVM: arm64: vgic-its: Implement ITS command queue command handlers
The connection between a device, an event ID, the LPI number and the
associated CPU is stored in in-memory tables in a GICv3, but their
format is not specified by the spec. Instead software uses a command
queue in a ring buffer to let an ITS implementation use its own
format.
Implement handlers for the various ITS commands and let them store
the requested relation into our own data structures. Those data
structures are protected by the its_lock mutex.
Our internal ring buffer read and write pointers are protected by the
its_cmd mutex, so that only one VCPU per ITS can handle commands at
any given time.
Error handling is very basic at the moment, as we don't have a good
way of communicating errors to the guest (usually an SError).
The INT command handler is missing from this patch, as we gain the
capability of actually injecting MSIs into the guest only later on.

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 f9f77af9e2 KVM: arm64: vgic-its: Allow updates of LPI configuration table
The (system-wide) LPI configuration table is held in a table in
(guest) memory. To achieve reasonable performance, we cache this data
in our struct vgic_irq. If the guest updates the configuration data
(which consists of the enable bit and the priority value), it issues
an INV or INVALL command to allow us to update our information.
Provide functions that update that information for one LPI or all LPIs
mapped to a specific collection.

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 18:14:37 +01:00
Andre Przywara 33d3bc9556 KVM: arm64: vgic-its: Read initial LPI pending table
The LPI pending status for a GICv3 redistributor is held in a table
in (guest) memory. To achieve reasonable performance, we cache the
pending bit in our struct vgic_irq. The initial pending state must be
read from guest memory upon enabling LPIs for this redistributor.
As we can't access the guest memory while we hold the lpi_list spinlock,
we create a snapshot of the LPI list and iterate over that.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:14:37 +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 8a39d00670 KVM: kvm_io_bus: Add kvm_io_bus_get_dev() call
The kvm_io_bus framework is a nice place of holding information about
various MMIO regions for kernel emulated devices.
Add a call to retrieve the kvm_io_device structure which is associated
with a certain MMIO address. This avoids to duplicate kvm_io_bus'
knowledge of MMIO regions without having to fake MMIO calls if a user
needs the device a certain MMIO address belongs to.
This will be used by the ITS emulation to get the associated ITS device
when someone triggers an MSI via an ioctl from userspace.

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>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:10:40 +01:00
Andre Przywara 42c8870f90 KVM: arm/arm64: vgic: Check return value for kvm_register_vgic_device
kvm_register_device_ops() can return an error, so lets check its return
value and propagate this up the call chain.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:10:08 +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
Paolo Bonzini 557abc40d1 KVM: remove kvm_vcpu_compatible
The new created_vcpus field makes it possible to avoid the race between
irqchip and VCPU creation in a much nicer way; just check under kvm->lock
whether a VCPU has already been created.

We can then remove KVM_APIC_ARCHITECTURE too, because at this point the
symbol is only governing the default definition of kvm_vcpu_compatible.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-16 00:05:00 +02:00
Paolo Bonzini 6c7caebc26 KVM: introduce kvm->created_vcpus
The race between creating the irqchip and the first VCPU is
currently fixed by checking the presence of an irqchip before
updating kvm->online_vcpus, and undoing the whole VCPU creation
if someone created the irqchip in the meanwhile.

Instead, introduce a new field in struct kvm that will count VCPUs
under a mutex, without the atomic access and memory ordering that we
need elsewhere to protect the vcpus array.  This also plugs the race
and is more easily applicable in all similar circumstances.

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-16 00:05:00 +02:00
Paolo Bonzini f8c1b85b25 KVM: x86: avoid vmalloc(0) in the KVM_SET_CPUID
This causes an ugly dmesg splat.  Beautified syzkaller testcase:

    #include <unistd.h>
    #include <sys/syscall.h>
    #include <sys/ioctl.h>
    #include <fcntl.h>
    #include <linux/kvm.h>

    long r[8];

    int main()
    {
        struct kvm_irq_routing ir = { 0 };
        r[2] = open("/dev/kvm", O_RDWR);
        r[3] = ioctl(r[2], KVM_CREATE_VM, 0);
        r[4] = ioctl(r[3], KVM_SET_GSI_ROUTING, &ir);
        return 0;
    }

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2016-06-02 17:38:50 +02:00
Paolo Bonzini c622a3c21e KVM: irqfd: fix NULL pointer dereference in kvm_irq_map_gsi
Found by syzkaller:

    BUG: unable to handle kernel NULL pointer dereference at 0000000000000120
    IP: [<ffffffffa0797202>] kvm_irq_map_gsi+0x12/0x90 [kvm]
    PGD 6f80b067 PUD b6535067 PMD 0
    Oops: 0000 [#1] SMP
    CPU: 3 PID: 4988 Comm: a.out Not tainted 4.4.9-300.fc23.x86_64 #1
    [...]
    Call Trace:
     [<ffffffffa0795f62>] irqfd_update+0x32/0xc0 [kvm]
     [<ffffffffa0796c7c>] kvm_irqfd+0x3dc/0x5b0 [kvm]
     [<ffffffffa07943f4>] kvm_vm_ioctl+0x164/0x6f0 [kvm]
     [<ffffffff81241648>] do_vfs_ioctl+0x298/0x480
     [<ffffffff812418a9>] SyS_ioctl+0x79/0x90
     [<ffffffff817a1062>] tracesys_phase2+0x84/0x89
    Code: b5 71 a7 e0 5b 41 5c 41 5d 5d f3 c3 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 8b 8f 10 2e 00 00 31 c0 48 89 e5 <39> 91 20 01 00 00 76 6a 48 63 d2 48 8b 94 d1 28 01 00 00 48 85
    RIP  [<ffffffffa0797202>] kvm_irq_map_gsi+0x12/0x90 [kvm]
     RSP <ffff8800926cbca8>
    CR2: 0000000000000120

Testcase:

    #include <unistd.h>
    #include <sys/syscall.h>
    #include <string.h>
    #include <stdint.h>
    #include <linux/kvm.h>
    #include <fcntl.h>
    #include <sys/ioctl.h>

    long r[26];

    int main()
    {
        memset(r, -1, sizeof(r));
        r[2] = open("/dev/kvm", 0);
        r[3] = ioctl(r[2], KVM_CREATE_VM, 0);

        struct kvm_irqfd ifd;
        ifd.fd = syscall(SYS_eventfd2, 5, 0);
        ifd.gsi = 3;
        ifd.flags = 2;
        ifd.resamplefd = ifd.fd;
        r[25] = ioctl(r[3], KVM_IRQFD, &ifd);
        return 0;
    }

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2016-06-02 17:38:50 +02:00
Marc Zyngier 05fb05a6ca KVM: arm/arm64: vgic-new: Removel harmful BUG_ON
When changing the active bit from an MMIO trap, we decide to
explode if the intid is that of a private interrupt.

This flawed logic comes from the fact that we were assuming that
kvm_vcpu_kick() as called by kvm_arm_halt_vcpu() would not return before
the called vcpu responded, but this is not the case, so we need to
perform this wait even for private interrupts.

Dropping the BUG_ON seems like the right thing to do.

 [ Commit message tweaked by Christoffer ]

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-06-02 11:52:21 +02:00
Marc Zyngier 637d122baa KVM: arm/arm64: vgic-v3: Always resample level interrupts
When reading back from the list registers, we need to perform
two actions for level interrupts:
1) clear the soft-pending bit if the interrupt is not pending
   anymore *in the list register*
2) resample the line level and propagate it to the pending state

But these two actions shouldn't be linked, and we should *always*
resample the line level, no matter what state is in the list
register. Otherwise, we may end-up injecting spurious interrupts
that have been already retired.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-05-31 16:12:16 +02:00
Marc Zyngier df7942d17e KVM: arm/arm64: vgic-v2: Always resample level interrupts
When reading back from the list registers, we need to perform
two actions for level interrupts:
1) clear the soft-pending bit if the interrupt is not pending
   anymore *in the list register*
2) resample the line level and propagate it to the pending state

But these two actions shouldn't be linked, and we should *always*
resample the line level, no matter what state is in the list
register. Otherwise, we may end-up injecting spurious interrupts
that have been already retired.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-05-31 16:12:15 +02:00
Christoffer Dall 4d3afc9bad KVM: arm/arm64: vgic-v2: Clear all dirty LRs
When saving the state of the list registers, it is critical to
reset them zero, as we could otherwise leave unexpected EOI
interrupts pending for virtual level interrupts.

Cc: stable@vger.kernel.org # v4.6+
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-05-31 16:09:28 +02:00
Janosch Frank 536a6f88c4 KVM: Create debugfs dir and stat files for each VM
This patch adds a kvm debugfs subdirectory for each VM, which is named
after its pid and file descriptor. The directories contain the same
kind of files that are already in the kvm debugfs directory, but the
data exported through them is now VM specific.

This makes the debugfs kvm data a convenient alternative to the
tracepoints which already have per VM data. The debugfs data is easy
to read and low overhead.

CC: Dan Carpenter <dan.carpenter@oracle.com> [includes fixes by Dan Carpenter]
Signed-off-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-25 16:12:05 +02:00
Paolo Bonzini 44bcc92238 KVM/ARM Changes for v4.7 take 2
"The GIC is dead; Long live the GIC"
 
 This set of changes include the new vgic, which is a reimplementation of
 our horribly broken legacy vgic implementation.  The two implementations
 will live side-by-side (with the new being the configured default) for
 one kernel release and then we'll remove it.
 
 Also fixes a non-critical issue with virtual abort injection to guests.
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Merge tag 'kvm-arm-for-4-7-take2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-next

KVM/ARM Changes for v4.7 take 2

"The GIC is dead; Long live the GIC"

This set of changes include the new vgic, which is a reimplementation of
our horribly broken legacy vgic implementation.  The two implementations
will live side-by-side (with the new being the configured default) for
one kernel release and then we'll remove it.

Also fixes a non-critical issue with virtual abort injection to guests.
2016-05-24 12:10:51 +02:00
Christoffer Dall 35a2d58588 KVM: arm/arm64: vgic-new: Synchronize changes to active state
When modifying the active state of an interrupt via the MMIO interface,
we should ensure that the write has the intended effect.

If a guest sets an interrupt to active, but that interrupt is already
flushed into a list register on a running VCPU, then that VCPU will
write the active state back into the struct vgic_irq upon returning from
the guest and syncing its state.  This is a non-benign race, because the
guest can observe that an interrupt is not active, and it can have a
reasonable expectations that other VCPUs will not ack any IRQs, and then
set the state to active, and expect it to stay that way.  Currently we
are not honoring this case.

Thefore, change both the SACTIVE and CACTIVE mmio handlers to stop the
world, change the irq state, potentially queue the irq if we're setting
it to active, and then continue.

We take this chance to slightly optimize these functions by not stopping
the world when touching private interrupts where there is inherently no
possible race.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-05-20 16:26:38 +02:00
Andre Przywara efffe55af5 KVM: arm/arm64: vgic-new: enable build
Now that the new VGIC implementation has reached feature parity with
the old one, add the new files to the build system and add a Kconfig
option to switch between the two versions.
We set the default to the new version to get maximum test coverage,
in case people experience problems they can switch back to the old
behaviour if needed.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-05-20 15:40:09 +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
Andre Przywara 03f0c94c73 KVM: arm/arm64: vgic-new: Wire up irqfd injection
Connect to the new VGIC to the irqfd framework, so that we can
inject IRQs.
GSI routing and MSI routing is not yet implemented.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-05-20 15:40:08 +02:00
Eric Auger f7b6985cc3 KVM: arm/arm64: vgic-new: Add vgic_v2/v3_enable
Enable the VGIC operation by properly initialising the registers
in the hypervisor GIC 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 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
Andre Przywara 878c569e45 KVM: arm/arm64: vgic-new: Add userland GIC CPU interface access
Using the VMCR accessors we provide access to GIC CPU interface state
to userland by wiring it up to the existing userland interface.
[Marc: move and make VMCR accessors static, streamline MMIO handlers]

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-05-20 15:40:05 +02:00
Andre Przywara e4823a7a1b KVM: arm/arm64: vgic-new: Add GICH_VMCR accessors
Since the GIC CPU interface is always virtualized by the hardware,
we don't have CPU interface state information readily available in our
emulation if userland wants to save or restore it.
Fortunately the GIC hypervisor interface provides the VMCR register to
access the required virtual CPU interface bits.
Provide wrappers for GICv2 and GICv3 hosts to have access to this
register.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-05-20 15:40:04 +02:00
Andre Przywara 7d450e2821 KVM: arm/arm64: vgic-new: Add userland access to VGIC dist registers
Userland may want to save and restore the state of the in-kernel VGIC,
so we provide the code which takes a userland request and translate
that into calls to our MMIO framework.

From Christoffer:
When accessing the VGIC state from userspace we really don't want a VCPU
to be messing with the state at the same time, and the API specifies
that we should return -EBUSY if any VCPUs are running.
Check and prevent VCPUs from running by grabbing their mutexes, one by
one, and error out if we fail.
(Note: This could potentially be simplified to just do a simple check
and see if any VCPUs are running, and return -EBUSY then, without
enforcing the locking throughout the duration of the uaccess, if we
think that taking/releasing all these mutexes for every single GIC
register access is too heavyweight.)

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-05-20 15:40:03 +02:00
Christoffer Dall c3199f28e0 KVM: arm/arm64: vgic-new: Export register access interface
Userland can access the emulated GIC to save and restore its state
for initialization or migration purposes.
The kvm_io_bus API requires an absolute gpa, which does not fit the
KVM_DEV_ARM_VGIC_GRP_DIST_REGS user API, that only provides relative
offsets. So we provide a wrapper to plug into our MMIO framework and
find the respective register handler.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
2016-05-20 15:40:03 +02:00
Eric Auger f94591e2e6 KVM: arm/arm64: vgic-new: vgic_kvm_device: access to VGIC registers
This patch implements the switches for KVM_DEV_ARM_VGIC_GRP_DIST_REGS
and KVM_DEV_ARM_VGIC_GRP_CPU_REGS API which allows the userspace to
access VGIC registers.

Signed-off-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-05-20 15:40:02 +02:00
Eric Auger e5c3029467 KVM: arm/arm64: vgic-new: vgic_kvm_device: KVM_DEV_ARM_VGIC_GRP_ADDR
This patch implements the KVM_DEV_ARM_VGIC_GRP_ADDR group which
enables to set the base address of GIC regions as seen by the guest.

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 15:40:02 +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
Eric Auger afcc7c50ce KVM: arm/arm64: vgic-new: vgic_kvm_device: KVM_DEV_ARM_VGIC_GRP_CTRL
This patch implements the KVM_DEV_ARM_VGIC_GRP_CTRL group API
featuring KVM_DEV_ARM_VGIC_CTRL_INIT attribute. The vgic_init
function is not yet implemented though.

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 15:40:00 +02:00
Eric Auger fca256026b KVM: arm/arm64: vgic-new: vgic_kvm_device: KVM_DEV_ARM_VGIC_GRP_NR_IRQS
This patch implements the KVM_DEV_ARM_VGIC_GRP_NR_IRQS group. This
modality is supported by both VGIC V2 and V3 KVM device as will be
other groups, hence the introduction of common helpers.

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 15:40:00 +02:00
Eric Auger c86c772191 KVM: arm/arm64: vgic-new: vgic_kvm_device: KVM device ops registration
This patch introduces the skeleton for the KVM device operations
associated to KVM_DEV_TYPE_ARM_VGIC_V2 and KVM_DEV_TYPE_ARM_VGIC_V3.

At that stage kvm_vgic_create is stubbed.

Signed-off-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-05-20 15:39:59 +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
Andre Przywara 78a714aba0 KVM: arm/arm64: vgic-new: Add GICv3 IROUTER register handlers
Since GICv3 supports much more than the 8 CPUs the GICv2 ITARGETSR
register can handle, the new IROUTER register covers the whole range
of possible target (V)CPUs by using the same MPIDR that the cores
report themselves.
In addition to translating this MPIDR into a vcpu pointer we store
the originally written value as well. The architecture allows to
write any values into the register, which must be read back as written.

Since we don't support affinity level 3, we don't need to take care
about the upper word of this 64-bit register, which simplifies the
handling a bit.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-05-20 15:39:58 +02:00
Andre Przywara 54f59d2b3a KVM: arm/arm64: vgic-new: Add GICv3 IDREGS register handler
We implement the only one ID register that is required by the
architecture, also this is the one that Linux actually checks.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-05-20 15:39:57 +02:00
Andre Przywara 741972d8a6 KVM: arm/arm64: vgic-new: Add GICv3 redistributor IIDR and TYPER handler
The redistributor TYPER tells the OS about the associated MPIDR,
also the LAST bit is crucial to determine the number of redistributors.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-05-20 15:39:57 +02:00
Andre Przywara fd59ed3be1 KVM: arm/arm64: vgic-new: Add GICv3 CTLR, IIDR, TYPER handlers
As in the GICv2 emulation we handle those three registers in one
function.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-05-20 15:39:56 +02:00
Andre Przywara ed9b8cefa9 KVM: arm/arm64: vgic-new: Add GICv3 MMIO handling framework
Create a new file called vgic-mmio-v3.c and describe the GICv3
distributor and redistributor registers there.
This adds a special macro to deal with the split of SGI/PPI in the
redistributor and SPIs in the distributor, which allows us to reuse
the existing GICv2 handlers for those registers which are compatible.
Also we provide a function to deal with the registration of the two
separate redistributor frames per VCPU.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-05-20 15:39:56 +02:00
Andre Przywara ed40213ef9 KVM: arm/arm64: vgic-new: Add SGIPENDR register handlers
As this register is v2 specific, its implementation lives entirely
in vgic-mmio-v2.c.
This register allows setting the source mask of an IPI.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-05-20 15:39:55 +02:00
Andre Przywara 55cc01fb90 KVM: arm/arm64: vgic-new: Add SGIR register handler
Triggering an IPI via this register is v2 specific, so the
implementation lives entirely in vgic-mmio-v2.c.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-05-20 15:39:55 +02:00