From f94591e2e6fdca6e9a2cbf23e36a8803b4f605fe Mon Sep 17 00:00:00 2001 From: Eric Auger Date: Mon, 21 Dec 2015 17:34:52 +0100 Subject: 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 Signed-off-by: Andre Przywara Reviewed-by: Christoffer Dall --- virt/kvm/arm/vgic/vgic-kvm-device.c | 53 +++++++++++++++++++++++++++++++++++-- virt/kvm/arm/vgic/vgic-mmio-v2.c | 38 ++++++++++++++++++++++++++ virt/kvm/arm/vgic/vgic.h | 1 + 3 files changed, 90 insertions(+), 2 deletions(-) (limited to 'virt') diff --git a/virt/kvm/arm/vgic/vgic-kvm-device.c b/virt/kvm/arm/vgic/vgic-kvm-device.c index a7090970be72..78621283a301 100644 --- a/virt/kvm/arm/vgic/vgic-kvm-device.c +++ b/virt/kvm/arm/vgic/vgic-kvm-device.c @@ -226,6 +226,21 @@ void kvm_register_vgic_device(unsigned long type) } } +/** vgic_attr_regs_access: allows user space to read/write VGIC registers + * + * @dev: kvm device handle + * @attr: kvm device attribute + * @reg: address the value is read or written + * @is_write: write flag + * + */ +static int vgic_attr_regs_access(struct kvm_device *dev, + struct kvm_device_attr *attr, + u32 *reg, bool is_write) +{ + return -ENXIO; +} + /* V2 ops */ static int vgic_v2_set_attr(struct kvm_device *dev, @@ -234,8 +249,23 @@ static int vgic_v2_set_attr(struct kvm_device *dev, int ret; ret = vgic_set_common_attr(dev, attr); - return ret; + if (ret != -ENXIO) + return ret; + + switch (attr->group) { + case KVM_DEV_ARM_VGIC_GRP_DIST_REGS: + case KVM_DEV_ARM_VGIC_GRP_CPU_REGS: { + u32 __user *uaddr = (u32 __user *)(long)attr->addr; + u32 reg; + + if (get_user(reg, uaddr)) + return -EFAULT; + return vgic_attr_regs_access(dev, attr, ®, true); + } + } + + return -ENXIO; } static int vgic_v2_get_attr(struct kvm_device *dev, @@ -244,7 +274,23 @@ static int vgic_v2_get_attr(struct kvm_device *dev, int ret; ret = vgic_get_common_attr(dev, attr); - return ret; + if (ret != -ENXIO) + return ret; + + switch (attr->group) { + case KVM_DEV_ARM_VGIC_GRP_DIST_REGS: + case KVM_DEV_ARM_VGIC_GRP_CPU_REGS: { + u32 __user *uaddr = (u32 __user *)(long)attr->addr; + u32 reg = 0; + + ret = vgic_attr_regs_access(dev, attr, ®, false); + if (ret) + return ret; + return put_user(reg, uaddr); + } + } + + return -ENXIO; } static int vgic_v2_has_attr(struct kvm_device *dev, @@ -258,6 +304,9 @@ static int vgic_v2_has_attr(struct kvm_device *dev, return 0; } break; + case KVM_DEV_ARM_VGIC_GRP_DIST_REGS: + case KVM_DEV_ARM_VGIC_GRP_CPU_REGS: + return vgic_v2_has_attr_regs(dev, attr); case KVM_DEV_ARM_VGIC_GRP_NR_IRQS: return 0; case KVM_DEV_ARM_VGIC_GRP_CTRL: diff --git a/virt/kvm/arm/vgic/vgic-mmio-v2.c b/virt/kvm/arm/vgic/vgic-mmio-v2.c index 3925d4cbec62..71896900ad12 100644 --- a/virt/kvm/arm/vgic/vgic-mmio-v2.c +++ b/virt/kvm/arm/vgic/vgic-mmio-v2.c @@ -258,3 +258,41 @@ unsigned int vgic_v2_init_dist_iodev(struct vgic_io_device *dev) return SZ_4K; } + +int vgic_v2_has_attr_regs(struct kvm_device *dev, struct kvm_device_attr *attr) +{ + int nr_irqs = dev->kvm->arch.vgic.nr_spis + VGIC_NR_PRIVATE_IRQS; + const struct vgic_register_region *regions; + gpa_t addr; + int nr_regions, i, len; + + addr = attr->attr & KVM_DEV_ARM_VGIC_OFFSET_MASK; + + switch (attr->group) { + case KVM_DEV_ARM_VGIC_GRP_DIST_REGS: + regions = vgic_v2_dist_registers; + nr_regions = ARRAY_SIZE(vgic_v2_dist_registers); + break; + case KVM_DEV_ARM_VGIC_GRP_CPU_REGS: + return -ENXIO; /* TODO: describe CPU i/f regs also */ + default: + return -ENXIO; + } + + /* We only support aligned 32-bit accesses. */ + if (addr & 3) + return -ENXIO; + + for (i = 0; i < nr_regions; i++) { + if (regions[i].bits_per_irq) + len = (regions[i].bits_per_irq * nr_irqs) / 8; + else + len = regions[i].len; + + if (regions[i].reg_offset <= addr && + regions[i].reg_offset + len > addr) + return 0; + } + + return -ENXIO; +} diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h index 6abc9a35c228..a264c5ff476e 100644 --- a/virt/kvm/arm/vgic/vgic.h +++ b/virt/kvm/arm/vgic/vgic.h @@ -37,6 +37,7 @@ void vgic_v2_fold_lr_state(struct kvm_vcpu *vcpu); void vgic_v2_populate_lr(struct kvm_vcpu *vcpu, struct vgic_irq *irq, int lr); void vgic_v2_clear_lr(struct kvm_vcpu *vcpu, int lr); void vgic_v2_set_underflow(struct kvm_vcpu *vcpu); +int vgic_v2_has_attr_regs(struct kvm_device *dev, struct kvm_device_attr *attr); int vgic_register_dist_iodev(struct kvm *kvm, gpa_t dist_base_address, enum vgic_type); -- cgit v1.2.3-59-g8ed1b