diff options
Diffstat (limited to 'virt/kvm/arm/vgic/vgic-kvm-device.c')
| -rw-r--r-- | virt/kvm/arm/vgic/vgic-kvm-device.c | 133 |
1 files changed, 85 insertions, 48 deletions
diff --git a/virt/kvm/arm/vgic/vgic-kvm-device.c b/virt/kvm/arm/vgic/vgic-kvm-device.c index 1813f93b5cde..ce1f4ed9daf4 100644 --- a/virt/kvm/arm/vgic/vgic-kvm-device.c +++ b/virt/kvm/arm/vgic/vgic-kvm-device.c @@ -71,7 +71,6 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write) addr_ptr = &vgic->vgic_cpu_base; alignment = SZ_4K; break; -#ifdef CONFIG_KVM_ARM_VGIC_V3 case KVM_VGIC_V3_ADDR_TYPE_DIST: type_needed = KVM_DEV_TYPE_ARM_VGIC_V3; addr_ptr = &vgic->vgic_dist_base; @@ -82,7 +81,6 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write) addr_ptr = &vgic->vgic_redist_base; alignment = SZ_64K; break; -#endif default: r = -ENODEV; goto out; @@ -219,52 +217,65 @@ int kvm_register_vgic_device(unsigned long type) ret = kvm_register_device_ops(&kvm_arm_vgic_v2_ops, KVM_DEV_TYPE_ARM_VGIC_V2); break; -#ifdef CONFIG_KVM_ARM_VGIC_V3 case KVM_DEV_TYPE_ARM_VGIC_V3: ret = kvm_register_device_ops(&kvm_arm_vgic_v3_ops, KVM_DEV_TYPE_ARM_VGIC_V3); + +#ifdef CONFIG_KVM_ARM_VGIC_V3_ITS if (ret) break; ret = kvm_vgic_register_its_device(); - break; #endif + break; } return ret; } -/** 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) -{ +struct vgic_reg_attr { + struct kvm_vcpu *vcpu; gpa_t addr; - int cpuid, ret, c; - struct kvm_vcpu *vcpu, *tmp_vcpu; - int vcpu_lock_idx = -1; +}; + +static int parse_vgic_v2_attr(struct kvm_device *dev, + struct kvm_device_attr *attr, + struct vgic_reg_attr *reg_attr) +{ + int cpuid; cpuid = (attr->attr & KVM_DEV_ARM_VGIC_CPUID_MASK) >> KVM_DEV_ARM_VGIC_CPUID_SHIFT; - vcpu = kvm_get_vcpu(dev->kvm, cpuid); - addr = attr->attr & KVM_DEV_ARM_VGIC_OFFSET_MASK; - mutex_lock(&dev->kvm->lock); + if (cpuid >= atomic_read(&dev->kvm->online_vcpus)) + return -EINVAL; - ret = vgic_init(dev->kvm); - if (ret) - goto out; + reg_attr->vcpu = kvm_get_vcpu(dev->kvm, cpuid); + reg_attr->addr = attr->attr & KVM_DEV_ARM_VGIC_OFFSET_MASK; - if (cpuid >= atomic_read(&dev->kvm->online_vcpus)) { - ret = -EINVAL; - goto out; + return 0; +} + +/* unlocks vcpus from @vcpu_lock_idx and smaller */ +static void unlock_vcpus(struct kvm *kvm, int vcpu_lock_idx) +{ + struct kvm_vcpu *tmp_vcpu; + + for (; vcpu_lock_idx >= 0; vcpu_lock_idx--) { + tmp_vcpu = kvm_get_vcpu(kvm, vcpu_lock_idx); + mutex_unlock(&tmp_vcpu->mutex); } +} + +static void unlock_all_vcpus(struct kvm *kvm) +{ + unlock_vcpus(kvm, atomic_read(&kvm->online_vcpus) - 1); +} + +/* Returns true if all vcpus were locked, false otherwise */ +static bool lock_all_vcpus(struct kvm *kvm) +{ + struct kvm_vcpu *tmp_vcpu; + int c; /* * Any time a vcpu is run, vcpu_load is called which tries to grab the @@ -272,11 +283,49 @@ static int vgic_attr_regs_access(struct kvm_device *dev, * that no other VCPUs are run and fiddle with the vgic state while we * access it. */ - ret = -EBUSY; - kvm_for_each_vcpu(c, tmp_vcpu, dev->kvm) { - if (!mutex_trylock(&tmp_vcpu->mutex)) - goto out; - vcpu_lock_idx = c; + kvm_for_each_vcpu(c, tmp_vcpu, kvm) { + if (!mutex_trylock(&tmp_vcpu->mutex)) { + unlock_vcpus(kvm, c - 1); + return false; + } + } + + return true; +} + +/** + * vgic_attr_regs_access_v2 - allows user space to access VGIC v2 state + * + * @dev: kvm device handle + * @attr: kvm device attribute + * @reg: address the value is read or written + * @is_write: true if userspace is writing a register + */ +static int vgic_attr_regs_access_v2(struct kvm_device *dev, + struct kvm_device_attr *attr, + u32 *reg, bool is_write) +{ + struct vgic_reg_attr reg_attr; + gpa_t addr; + struct kvm_vcpu *vcpu; + int ret; + + ret = parse_vgic_v2_attr(dev, attr, ®_attr); + if (ret) + return ret; + + vcpu = reg_attr.vcpu; + addr = reg_attr.addr; + + mutex_lock(&dev->kvm->lock); + + ret = vgic_init(dev->kvm); + if (ret) + goto out; + + if (!lock_all_vcpus(dev->kvm)) { + ret = -EBUSY; + goto out; } switch (attr->group) { @@ -291,18 +340,12 @@ static int vgic_attr_regs_access(struct kvm_device *dev, break; } + unlock_all_vcpus(dev->kvm); out: - for (; vcpu_lock_idx >= 0; vcpu_lock_idx--) { - tmp_vcpu = kvm_get_vcpu(dev->kvm, vcpu_lock_idx); - mutex_unlock(&tmp_vcpu->mutex); - } - mutex_unlock(&dev->kvm->lock); return ret; } -/* V2 ops */ - static int vgic_v2_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr) { @@ -321,7 +364,7 @@ static int vgic_v2_set_attr(struct kvm_device *dev, if (get_user(reg, uaddr)) return -EFAULT; - return vgic_attr_regs_access(dev, attr, ®, true); + return vgic_attr_regs_access_v2(dev, attr, ®, true); } } @@ -343,7 +386,7 @@ static int vgic_v2_get_attr(struct kvm_device *dev, u32 __user *uaddr = (u32 __user *)(long)attr->addr; u32 reg = 0; - ret = vgic_attr_regs_access(dev, attr, ®, false); + ret = vgic_attr_regs_access_v2(dev, attr, ®, false); if (ret) return ret; return put_user(reg, uaddr); @@ -387,10 +430,6 @@ struct kvm_device_ops kvm_arm_vgic_v2_ops = { .has_attr = vgic_v2_has_attr, }; -/* V3 ops */ - -#ifdef CONFIG_KVM_ARM_VGIC_V3 - static int vgic_v3_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr) { @@ -433,5 +472,3 @@ struct kvm_device_ops kvm_arm_vgic_v3_ops = { .get_attr = vgic_v3_get_attr, .has_attr = vgic_v3_has_attr, }; - -#endif /* CONFIG_KVM_ARM_VGIC_V3 */ |