diff options
Diffstat (limited to 'virt/kvm/arm/vgic/vgic-kvm-device.c')
| -rw-r--r-- | virt/kvm/arm/vgic/vgic-kvm-device.c | 431 |
1 files changed, 431 insertions, 0 deletions
diff --git a/virt/kvm/arm/vgic/vgic-kvm-device.c b/virt/kvm/arm/vgic/vgic-kvm-device.c new file mode 100644 index 0000000..0130c4b --- /dev/null +++ b/virt/kvm/arm/vgic/vgic-kvm-device.c @@ -0,0 +1,431 @@ +/* + * VGIC: KVM DEVICE API + * + * Copyright (C) 2015 ARM Ltd. + * Author: Marc Zyngier <marc.zyngier@arm.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ +#include <linux/kvm_host.h> +#include <kvm/arm_vgic.h> +#include <linux/uaccess.h> +#include <asm/kvm_mmu.h> +#include "vgic.h" + +/* common helpers */ + +static int vgic_check_ioaddr(struct kvm *kvm, phys_addr_t *ioaddr, + phys_addr_t addr, phys_addr_t alignment) +{ + if (addr & ~KVM_PHYS_MASK) + return -E2BIG; + + if (!IS_ALIGNED(addr, alignment)) + return -EINVAL; + + if (!IS_VGIC_ADDR_UNDEF(*ioaddr)) + return -EEXIST; + + return 0; +} + +/** + * kvm_vgic_addr - set or get vgic VM base addresses + * @kvm: pointer to the vm struct + * @type: the VGIC addr type, one of KVM_VGIC_V[23]_ADDR_TYPE_XXX + * @addr: pointer to address value + * @write: if true set the address in the VM address space, if false read the + * address + * + * Set or get the vgic base addresses for the distributor and the virtual CPU + * interface in the VM physical address space. These addresses are properties + * of the emulated core/SoC and therefore user space initially knows this + * information. + * Check them for sanity (alignment, double assignment). We can't check for + * overlapping regions in case of a virtual GICv3 here, since we don't know + * the number of VCPUs yet, so we defer this check to map_resources(). + */ +int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write) +{ + int r = 0; + struct vgic_dist *vgic = &kvm->arch.vgic; + int type_needed; + phys_addr_t *addr_ptr, alignment; + + mutex_lock(&kvm->lock); + switch (type) { + case KVM_VGIC_V2_ADDR_TYPE_DIST: + type_needed = KVM_DEV_TYPE_ARM_VGIC_V2; + addr_ptr = &vgic->vgic_dist_base; + alignment = SZ_4K; + break; + case KVM_VGIC_V2_ADDR_TYPE_CPU: + type_needed = KVM_DEV_TYPE_ARM_VGIC_V2; + 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; + alignment = SZ_64K; + break; + case KVM_VGIC_V3_ADDR_TYPE_REDIST: + type_needed = KVM_DEV_TYPE_ARM_VGIC_V3; + addr_ptr = &vgic->vgic_redist_base; + alignment = SZ_64K; + break; +#endif + default: + r = -ENODEV; + goto out; + } + + if (vgic->vgic_model != type_needed) { + r = -ENODEV; + goto out; + } + + if (write) { + r = vgic_check_ioaddr(kvm, addr_ptr, *addr, alignment); + if (!r) + *addr_ptr = *addr; + } else { + *addr = *addr_ptr; + } + +out: + mutex_unlock(&kvm->lock); + return r; +} + +static int vgic_set_common_attr(struct kvm_device *dev, + struct kvm_device_attr *attr) +{ + int r; + + switch (attr->group) { + case KVM_DEV_ARM_VGIC_GRP_ADDR: { + u64 __user *uaddr = (u64 __user *)(long)attr->addr; + u64 addr; + unsigned long type = (unsigned long)attr->attr; + + if (copy_from_user(&addr, uaddr, sizeof(addr))) + return -EFAULT; + + r = kvm_vgic_addr(dev->kvm, type, &addr, true); + return (r == -ENODEV) ? -ENXIO : r; + } + case KVM_DEV_ARM_VGIC_GRP_NR_IRQS: { + u32 __user *uaddr = (u32 __user *)(long)attr->addr; + u32 val; + int ret = 0; + + if (get_user(val, uaddr)) + return -EFAULT; + + /* + * We require: + * - at least 32 SPIs on top of the 16 SGIs and 16 PPIs + * - at most 1024 interrupts + * - a multiple of 32 interrupts + */ + if (val < (VGIC_NR_PRIVATE_IRQS + 32) || + val > VGIC_MAX_RESERVED || + (val & 31)) + return -EINVAL; + + mutex_lock(&dev->kvm->lock); + + if (vgic_ready(dev->kvm) || dev->kvm->arch.vgic.nr_spis) + ret = -EBUSY; + else + dev->kvm->arch.vgic.nr_spis = + val - VGIC_NR_PRIVATE_IRQS; + + mutex_unlock(&dev->kvm->lock); + + return ret; + } + case KVM_DEV_ARM_VGIC_GRP_CTRL: { + switch (attr->attr) { + case KVM_DEV_ARM_VGIC_CTRL_INIT: + mutex_lock(&dev->kvm->lock); + r = vgic_init(dev->kvm); + mutex_unlock(&dev->kvm->lock); + return r; + } + break; + } + } + + return -ENXIO; +} + +static int vgic_get_common_attr(struct kvm_device *dev, + struct kvm_device_attr *attr) +{ + int r = -ENXIO; + + switch (attr->group) { + case KVM_DEV_ARM_VGIC_GRP_ADDR: { + u64 __user *uaddr = (u64 __user *)(long)attr->addr; + u64 addr; + unsigned long type = (unsigned long)attr->attr; + + r = kvm_vgic_addr(dev->kvm, type, &addr, false); + if (r) + return (r == -ENODEV) ? -ENXIO : r; + + if (copy_to_user(uaddr, &addr, sizeof(addr))) + return -EFAULT; + break; + } + case KVM_DEV_ARM_VGIC_GRP_NR_IRQS: { + u32 __user *uaddr = (u32 __user *)(long)attr->addr; + + r = put_user(dev->kvm->arch.vgic.nr_spis + + VGIC_NR_PRIVATE_IRQS, uaddr); + break; + } + } + + return r; +} + +static int vgic_create(struct kvm_device *dev, u32 type) +{ + return kvm_vgic_create(dev->kvm, type); +} + +static void vgic_destroy(struct kvm_device *dev) +{ + kfree(dev); +} + +void kvm_register_vgic_device(unsigned long type) +{ + switch (type) { + case KVM_DEV_TYPE_ARM_VGIC_V2: + 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: + kvm_register_device_ops(&kvm_arm_vgic_v3_ops, + KVM_DEV_TYPE_ARM_VGIC_V3); + break; +#endif + } +} + +/** 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) +{ + gpa_t addr; + int cpuid, ret, c; + struct kvm_vcpu *vcpu, *tmp_vcpu; + int vcpu_lock_idx = -1; + + 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); + + ret = vgic_init(dev->kvm); + if (ret) + goto out; + + if (cpuid >= atomic_read(&dev->kvm->online_vcpus)) { + ret = -EINVAL; + goto out; + } + + /* + * Any time a vcpu is run, vcpu_load is called which tries to grab the + * vcpu->mutex. By grabbing the vcpu->mutex of all VCPUs we ensure + * 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; + } + + switch (attr->group) { + case KVM_DEV_ARM_VGIC_GRP_CPU_REGS: + ret = vgic_v2_cpuif_uaccess(vcpu, is_write, addr, reg); + break; + case KVM_DEV_ARM_VGIC_GRP_DIST_REGS: + ret = vgic_v2_dist_uaccess(vcpu, is_write, addr, reg); + break; + default: + ret = -EINVAL; + break; + } + +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) +{ + int ret; + + ret = vgic_set_common_attr(dev, attr); + 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, + struct kvm_device_attr *attr) +{ + int ret; + + ret = vgic_get_common_attr(dev, attr); + 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, + struct kvm_device_attr *attr) +{ + switch (attr->group) { + case KVM_DEV_ARM_VGIC_GRP_ADDR: + switch (attr->attr) { + case KVM_VGIC_V2_ADDR_TYPE_DIST: + case KVM_VGIC_V2_ADDR_TYPE_CPU: + 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: + switch (attr->attr) { + case KVM_DEV_ARM_VGIC_CTRL_INIT: + return 0; + } + } + return -ENXIO; +} + +struct kvm_device_ops kvm_arm_vgic_v2_ops = { + .name = "kvm-arm-vgic-v2", + .create = vgic_create, + .destroy = vgic_destroy, + .set_attr = vgic_v2_set_attr, + .get_attr = vgic_v2_get_attr, + .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) +{ + return vgic_set_common_attr(dev, attr); +} + +static int vgic_v3_get_attr(struct kvm_device *dev, + struct kvm_device_attr *attr) +{ + return vgic_get_common_attr(dev, attr); +} + +static int vgic_v3_has_attr(struct kvm_device *dev, + struct kvm_device_attr *attr) +{ + switch (attr->group) { + case KVM_DEV_ARM_VGIC_GRP_ADDR: + switch (attr->attr) { + case KVM_VGIC_V3_ADDR_TYPE_DIST: + case KVM_VGIC_V3_ADDR_TYPE_REDIST: + return 0; + } + break; + case KVM_DEV_ARM_VGIC_GRP_NR_IRQS: + return 0; + case KVM_DEV_ARM_VGIC_GRP_CTRL: + switch (attr->attr) { + case KVM_DEV_ARM_VGIC_CTRL_INIT: + return 0; + } + } + return -ENXIO; +} + +struct kvm_device_ops kvm_arm_vgic_v3_ops = { + .name = "kvm-arm-vgic-v3", + .create = vgic_create, + .destroy = vgic_destroy, + .set_attr = vgic_v3_set_attr, + .get_attr = vgic_v3_get_attr, + .has_attr = vgic_v3_has_attr, +}; + +#endif /* CONFIG_KVM_ARM_VGIC_V3 */ + |
