KVM: arm/arm64: vgic: Implement support for userspace access

Read and write of some registers like ISPENDR and ICPENDR
from userspace requires special handling when compared to
guest access for these registers.

Refer to Documentation/virtual/kvm/devices/arm-vgic-v3.txt
for handling of ISPENDR, ICPENDR registers handling.

Add infrastructure to support guest and userspace read
and write for the required registers
Also moved vgic_uaccess from vgic-mmio-v2.c to vgic-mmio.c

Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@cavium.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

1 files changed, 0 insertions, 25 deletions

diff --git a/virt/kvm/arm/vgic/vgic-mmio-v2.c b/virt/kvm/arm/vgic/vgic-mmio-v2.c
index 07e67f1e25ef..270eb4ab528e 100644
--- a/virt/kvm/arm/vgic/vgic-mmio-v2.c
+++ b/virt/kvm/arm/vgic/vgic-mmio-v2.c
@@ -407,31 +407,6 @@ int vgic_v2_has_attr_regs(struct kvm_device *dev, struct kvm_device_attr *attr)
 	return -ENXIO;
 }
 
-/*
- * When userland tries to access the VGIC register handlers, we need to
- * create a usable struct vgic_io_device to be passed to the handlers and we
- * have to set up a buffer similar to what would have happened if a guest MMIO
- * access occurred, including doing endian conversions on BE systems.
- */
-static int vgic_uaccess(struct kvm_vcpu *vcpu, struct vgic_io_device *dev,
-			bool is_write, int offset, u32 *val)
-{
-	unsigned int len = 4;
-	u8 buf[4];
-	int ret;
-
-	if (is_write) {
-		vgic_data_host_to_mmio_bus(buf, len, *val);
-		ret = kvm_io_gic_ops.write(vcpu, &dev->dev, offset, len, buf);
-	} else {
-		ret = kvm_io_gic_ops.read(vcpu, &dev->dev, offset, len, buf);
-		if (!ret)
-			*val = vgic_data_mmio_bus_to_host(buf, len);
-	}
-
-	return ret;
-}
-
 int vgic_v2_cpuif_uaccess(struct kvm_vcpu *vcpu, bool is_write,
 			  int offset, u32 *val)
 {