diff options
Diffstat (limited to 'arch/arm64/kvm/vgic/vgic-mmio-v2.c')
| -rw-r--r-- | arch/arm64/kvm/vgic/vgic-mmio-v2.c | 550 |
1 files changed, 550 insertions, 0 deletions
diff --git a/arch/arm64/kvm/vgic/vgic-mmio-v2.c b/arch/arm64/kvm/vgic/vgic-mmio-v2.c new file mode 100644 index 000000000..b3cc51795 --- /dev/null +++ b/arch/arm64/kvm/vgic/vgic-mmio-v2.c @@ -0,0 +1,550 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * VGICv2 MMIO handling functions + */ + +#include <linux/irqchip/arm-gic.h> +#include <linux/kvm.h> +#include <linux/kvm_host.h> +#include <linux/nospec.h> + +#include <kvm/iodev.h> +#include <kvm/arm_vgic.h> + +#include "vgic.h" +#include "vgic-mmio.h" + +/* + * The Revision field in the IIDR have the following meanings: + * + * Revision 1: Report GICv2 interrupts as group 0 instead of group 1 + * Revision 2: Interrupt groups are guest-configurable and signaled using + * their configured groups. + */ + +static unsigned long vgic_mmio_read_v2_misc(struct kvm_vcpu *vcpu, + gpa_t addr, unsigned int len) +{ + struct vgic_dist *vgic = &vcpu->kvm->arch.vgic; + u32 value; + + switch (addr & 0x0c) { + case GIC_DIST_CTRL: + value = vgic->enabled ? GICD_ENABLE : 0; + break; + case GIC_DIST_CTR: + value = vgic->nr_spis + VGIC_NR_PRIVATE_IRQS; + value = (value >> 5) - 1; + value |= (atomic_read(&vcpu->kvm->online_vcpus) - 1) << 5; + break; + case GIC_DIST_IIDR: + value = (PRODUCT_ID_KVM << GICD_IIDR_PRODUCT_ID_SHIFT) | + (vgic->implementation_rev << GICD_IIDR_REVISION_SHIFT) | + (IMPLEMENTER_ARM << GICD_IIDR_IMPLEMENTER_SHIFT); + break; + default: + return 0; + } + + return value; +} + +static void vgic_mmio_write_v2_misc(struct kvm_vcpu *vcpu, + gpa_t addr, unsigned int len, + unsigned long val) +{ + struct vgic_dist *dist = &vcpu->kvm->arch.vgic; + bool was_enabled = dist->enabled; + + switch (addr & 0x0c) { + case GIC_DIST_CTRL: + dist->enabled = val & GICD_ENABLE; + if (!was_enabled && dist->enabled) + vgic_kick_vcpus(vcpu->kvm); + break; + case GIC_DIST_CTR: + case GIC_DIST_IIDR: + /* Nothing to do */ + return; + } +} + +static int vgic_mmio_uaccess_write_v2_misc(struct kvm_vcpu *vcpu, + gpa_t addr, unsigned int len, + unsigned long val) +{ + switch (addr & 0x0c) { + case GIC_DIST_IIDR: + if (val != vgic_mmio_read_v2_misc(vcpu, addr, len)) + return -EINVAL; + + /* + * If we observe a write to GICD_IIDR we know that userspace + * has been updated and has had a chance to cope with older + * kernels (VGICv2 IIDR.Revision == 0) incorrectly reporting + * interrupts as group 1, and therefore we now allow groups to + * be user writable. Doing this by default would break + * migration from old kernels to new kernels with legacy + * userspace. + */ + vcpu->kvm->arch.vgic.v2_groups_user_writable = true; + return 0; + } + + vgic_mmio_write_v2_misc(vcpu, addr, len, val); + return 0; +} + +static int vgic_mmio_uaccess_write_v2_group(struct kvm_vcpu *vcpu, + gpa_t addr, unsigned int len, + unsigned long val) +{ + if (vcpu->kvm->arch.vgic.v2_groups_user_writable) + vgic_mmio_write_group(vcpu, addr, len, val); + + return 0; +} + +static void vgic_mmio_write_sgir(struct kvm_vcpu *source_vcpu, + gpa_t addr, unsigned int len, + unsigned long val) +{ + int nr_vcpus = atomic_read(&source_vcpu->kvm->online_vcpus); + int intid = val & 0xf; + int targets = (val >> 16) & 0xff; + int mode = (val >> 24) & 0x03; + int c; + struct kvm_vcpu *vcpu; + unsigned long flags; + + switch (mode) { + case 0x0: /* as specified by targets */ + break; + case 0x1: + targets = (1U << nr_vcpus) - 1; /* all, ... */ + targets &= ~(1U << source_vcpu->vcpu_id); /* but self */ + break; + case 0x2: /* this very vCPU only */ + targets = (1U << source_vcpu->vcpu_id); + break; + case 0x3: /* reserved */ + return; + } + + kvm_for_each_vcpu(c, vcpu, source_vcpu->kvm) { + struct vgic_irq *irq; + + if (!(targets & (1U << c))) + continue; + + irq = vgic_get_irq(source_vcpu->kvm, vcpu, intid); + + raw_spin_lock_irqsave(&irq->irq_lock, flags); + irq->pending_latch = true; + irq->source |= 1U << source_vcpu->vcpu_id; + + vgic_queue_irq_unlock(source_vcpu->kvm, irq, flags); + vgic_put_irq(source_vcpu->kvm, irq); + } +} + +static unsigned long vgic_mmio_read_target(struct kvm_vcpu *vcpu, + gpa_t addr, unsigned int len) +{ + u32 intid = VGIC_ADDR_TO_INTID(addr, 8); + int i; + u64 val = 0; + + for (i = 0; i < len; i++) { + struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i); + + val |= (u64)irq->targets << (i * 8); + + vgic_put_irq(vcpu->kvm, irq); + } + + return val; +} + +static void vgic_mmio_write_target(struct kvm_vcpu *vcpu, + gpa_t addr, unsigned int len, + unsigned long val) +{ + u32 intid = VGIC_ADDR_TO_INTID(addr, 8); + u8 cpu_mask = GENMASK(atomic_read(&vcpu->kvm->online_vcpus) - 1, 0); + int i; + unsigned long flags; + + /* GICD_ITARGETSR[0-7] are read-only */ + if (intid < VGIC_NR_PRIVATE_IRQS) + return; + + for (i = 0; i < len; i++) { + struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, NULL, intid + i); + int target; + + raw_spin_lock_irqsave(&irq->irq_lock, flags); + + irq->targets = (val >> (i * 8)) & cpu_mask; + target = irq->targets ? __ffs(irq->targets) : 0; + irq->target_vcpu = kvm_get_vcpu(vcpu->kvm, target); + + raw_spin_unlock_irqrestore(&irq->irq_lock, flags); + vgic_put_irq(vcpu->kvm, irq); + } +} + +static unsigned long vgic_mmio_read_sgipend(struct kvm_vcpu *vcpu, + gpa_t addr, unsigned int len) +{ + u32 intid = addr & 0x0f; + int i; + u64 val = 0; + + for (i = 0; i < len; i++) { + struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i); + + val |= (u64)irq->source << (i * 8); + + vgic_put_irq(vcpu->kvm, irq); + } + return val; +} + +static void vgic_mmio_write_sgipendc(struct kvm_vcpu *vcpu, + gpa_t addr, unsigned int len, + unsigned long val) +{ + u32 intid = addr & 0x0f; + int i; + unsigned long flags; + + for (i = 0; i < len; i++) { + struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i); + + raw_spin_lock_irqsave(&irq->irq_lock, flags); + + irq->source &= ~((val >> (i * 8)) & 0xff); + if (!irq->source) + irq->pending_latch = false; + + raw_spin_unlock_irqrestore(&irq->irq_lock, flags); + vgic_put_irq(vcpu->kvm, irq); + } +} + +static void vgic_mmio_write_sgipends(struct kvm_vcpu *vcpu, + gpa_t addr, unsigned int len, + unsigned long val) +{ + u32 intid = addr & 0x0f; + int i; + unsigned long flags; + + for (i = 0; i < len; i++) { + struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i); + + raw_spin_lock_irqsave(&irq->irq_lock, flags); + + irq->source |= (val >> (i * 8)) & 0xff; + + if (irq->source) { + irq->pending_latch = true; + vgic_queue_irq_unlock(vcpu->kvm, irq, flags); + } else { + raw_spin_unlock_irqrestore(&irq->irq_lock, flags); + } + vgic_put_irq(vcpu->kvm, irq); + } +} + +#define GICC_ARCH_VERSION_V2 0x2 + +/* These are for userland accesses only, there is no guest-facing emulation. */ +static unsigned long vgic_mmio_read_vcpuif(struct kvm_vcpu *vcpu, + gpa_t addr, unsigned int len) +{ + struct vgic_vmcr vmcr; + u32 val; + + vgic_get_vmcr(vcpu, &vmcr); + + switch (addr & 0xff) { + case GIC_CPU_CTRL: + val = vmcr.grpen0 << GIC_CPU_CTRL_EnableGrp0_SHIFT; + val |= vmcr.grpen1 << GIC_CPU_CTRL_EnableGrp1_SHIFT; + val |= vmcr.ackctl << GIC_CPU_CTRL_AckCtl_SHIFT; + val |= vmcr.fiqen << GIC_CPU_CTRL_FIQEn_SHIFT; + val |= vmcr.cbpr << GIC_CPU_CTRL_CBPR_SHIFT; + val |= vmcr.eoim << GIC_CPU_CTRL_EOImodeNS_SHIFT; + + break; + case GIC_CPU_PRIMASK: + /* + * Our KVM_DEV_TYPE_ARM_VGIC_V2 device ABI exports the + * the PMR field as GICH_VMCR.VMPriMask rather than + * GICC_PMR.Priority, so we expose the upper five bits of + * priority mask to userspace using the lower bits in the + * unsigned long. + */ + val = (vmcr.pmr & GICV_PMR_PRIORITY_MASK) >> + GICV_PMR_PRIORITY_SHIFT; + break; + case GIC_CPU_BINPOINT: + val = vmcr.bpr; + break; + case GIC_CPU_ALIAS_BINPOINT: + val = vmcr.abpr; + break; + case GIC_CPU_IDENT: + val = ((PRODUCT_ID_KVM << 20) | + (GICC_ARCH_VERSION_V2 << 16) | + IMPLEMENTER_ARM); + break; + default: + return 0; + } + + return val; +} + +static void vgic_mmio_write_vcpuif(struct kvm_vcpu *vcpu, + gpa_t addr, unsigned int len, + unsigned long val) +{ + struct vgic_vmcr vmcr; + + vgic_get_vmcr(vcpu, &vmcr); + + switch (addr & 0xff) { + case GIC_CPU_CTRL: + vmcr.grpen0 = !!(val & GIC_CPU_CTRL_EnableGrp0); + vmcr.grpen1 = !!(val & GIC_CPU_CTRL_EnableGrp1); + vmcr.ackctl = !!(val & GIC_CPU_CTRL_AckCtl); + vmcr.fiqen = !!(val & GIC_CPU_CTRL_FIQEn); + vmcr.cbpr = !!(val & GIC_CPU_CTRL_CBPR); + vmcr.eoim = !!(val & GIC_CPU_CTRL_EOImodeNS); + + break; + case GIC_CPU_PRIMASK: + /* + * Our KVM_DEV_TYPE_ARM_VGIC_V2 device ABI exports the + * the PMR field as GICH_VMCR.VMPriMask rather than + * GICC_PMR.Priority, so we expose the upper five bits of + * priority mask to userspace using the lower bits in the + * unsigned long. + */ + vmcr.pmr = (val << GICV_PMR_PRIORITY_SHIFT) & + GICV_PMR_PRIORITY_MASK; + break; + case GIC_CPU_BINPOINT: + vmcr.bpr = val; + break; + case GIC_CPU_ALIAS_BINPOINT: + vmcr.abpr = val; + break; + } + + vgic_set_vmcr(vcpu, &vmcr); +} + +static unsigned long vgic_mmio_read_apr(struct kvm_vcpu *vcpu, + gpa_t addr, unsigned int len) +{ + int n; /* which APRn is this */ + + n = (addr >> 2) & 0x3; + + if (kvm_vgic_global_state.type == VGIC_V2) { + /* GICv2 hardware systems support max. 32 groups */ + if (n != 0) + return 0; + return vcpu->arch.vgic_cpu.vgic_v2.vgic_apr; + } else { + struct vgic_v3_cpu_if *vgicv3 = &vcpu->arch.vgic_cpu.vgic_v3; + + if (n > vgic_v3_max_apr_idx(vcpu)) + return 0; + + n = array_index_nospec(n, 4); + + /* GICv3 only uses ICH_AP1Rn for memory mapped (GICv2) guests */ + return vgicv3->vgic_ap1r[n]; + } +} + +static void vgic_mmio_write_apr(struct kvm_vcpu *vcpu, + gpa_t addr, unsigned int len, + unsigned long val) +{ + int n; /* which APRn is this */ + + n = (addr >> 2) & 0x3; + + if (kvm_vgic_global_state.type == VGIC_V2) { + /* GICv2 hardware systems support max. 32 groups */ + if (n != 0) + return; + vcpu->arch.vgic_cpu.vgic_v2.vgic_apr = val; + } else { + struct vgic_v3_cpu_if *vgicv3 = &vcpu->arch.vgic_cpu.vgic_v3; + + if (n > vgic_v3_max_apr_idx(vcpu)) + return; + + n = array_index_nospec(n, 4); + + /* GICv3 only uses ICH_AP1Rn for memory mapped (GICv2) guests */ + vgicv3->vgic_ap1r[n] = val; + } +} + +static const struct vgic_register_region vgic_v2_dist_registers[] = { + REGISTER_DESC_WITH_LENGTH_UACCESS(GIC_DIST_CTRL, + vgic_mmio_read_v2_misc, vgic_mmio_write_v2_misc, + NULL, vgic_mmio_uaccess_write_v2_misc, + 12, VGIC_ACCESS_32bit), + REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_IGROUP, + vgic_mmio_read_group, vgic_mmio_write_group, + NULL, vgic_mmio_uaccess_write_v2_group, 1, + VGIC_ACCESS_32bit), + REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_ENABLE_SET, + vgic_mmio_read_enable, vgic_mmio_write_senable, + NULL, vgic_uaccess_write_senable, 1, + VGIC_ACCESS_32bit), + REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_ENABLE_CLEAR, + vgic_mmio_read_enable, vgic_mmio_write_cenable, + NULL, vgic_uaccess_write_cenable, 1, + VGIC_ACCESS_32bit), + REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_PENDING_SET, + vgic_mmio_read_pending, vgic_mmio_write_spending, + vgic_uaccess_read_pending, vgic_uaccess_write_spending, 1, + VGIC_ACCESS_32bit), + REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_PENDING_CLEAR, + vgic_mmio_read_pending, vgic_mmio_write_cpending, + vgic_uaccess_read_pending, vgic_uaccess_write_cpending, 1, + VGIC_ACCESS_32bit), + REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_ACTIVE_SET, + vgic_mmio_read_active, vgic_mmio_write_sactive, + vgic_uaccess_read_active, vgic_mmio_uaccess_write_sactive, 1, + VGIC_ACCESS_32bit), + REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_ACTIVE_CLEAR, + vgic_mmio_read_active, vgic_mmio_write_cactive, + vgic_uaccess_read_active, vgic_mmio_uaccess_write_cactive, 1, + VGIC_ACCESS_32bit), + REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_PRI, + vgic_mmio_read_priority, vgic_mmio_write_priority, NULL, NULL, + 8, VGIC_ACCESS_32bit | VGIC_ACCESS_8bit), + REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_TARGET, + vgic_mmio_read_target, vgic_mmio_write_target, NULL, NULL, 8, + VGIC_ACCESS_32bit | VGIC_ACCESS_8bit), + REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_CONFIG, + vgic_mmio_read_config, vgic_mmio_write_config, NULL, NULL, 2, + VGIC_ACCESS_32bit), + REGISTER_DESC_WITH_LENGTH(GIC_DIST_SOFTINT, + vgic_mmio_read_raz, vgic_mmio_write_sgir, 4, + VGIC_ACCESS_32bit), + REGISTER_DESC_WITH_LENGTH(GIC_DIST_SGI_PENDING_CLEAR, + vgic_mmio_read_sgipend, vgic_mmio_write_sgipendc, 16, + VGIC_ACCESS_32bit | VGIC_ACCESS_8bit), + REGISTER_DESC_WITH_LENGTH(GIC_DIST_SGI_PENDING_SET, + vgic_mmio_read_sgipend, vgic_mmio_write_sgipends, 16, + VGIC_ACCESS_32bit | VGIC_ACCESS_8bit), +}; + +static const struct vgic_register_region vgic_v2_cpu_registers[] = { + REGISTER_DESC_WITH_LENGTH(GIC_CPU_CTRL, + vgic_mmio_read_vcpuif, vgic_mmio_write_vcpuif, 4, + VGIC_ACCESS_32bit), + REGISTER_DESC_WITH_LENGTH(GIC_CPU_PRIMASK, + vgic_mmio_read_vcpuif, vgic_mmio_write_vcpuif, 4, + VGIC_ACCESS_32bit), + REGISTER_DESC_WITH_LENGTH(GIC_CPU_BINPOINT, + vgic_mmio_read_vcpuif, vgic_mmio_write_vcpuif, 4, + VGIC_ACCESS_32bit), + REGISTER_DESC_WITH_LENGTH(GIC_CPU_ALIAS_BINPOINT, + vgic_mmio_read_vcpuif, vgic_mmio_write_vcpuif, 4, + VGIC_ACCESS_32bit), + REGISTER_DESC_WITH_LENGTH(GIC_CPU_ACTIVEPRIO, + vgic_mmio_read_apr, vgic_mmio_write_apr, 16, + VGIC_ACCESS_32bit), + REGISTER_DESC_WITH_LENGTH(GIC_CPU_IDENT, + vgic_mmio_read_vcpuif, vgic_mmio_write_vcpuif, 4, + VGIC_ACCESS_32bit), +}; + +unsigned int vgic_v2_init_dist_iodev(struct vgic_io_device *dev) +{ + dev->regions = vgic_v2_dist_registers; + dev->nr_regions = ARRAY_SIZE(vgic_v2_dist_registers); + + kvm_iodevice_init(&dev->dev, &kvm_io_gic_ops); + + return SZ_4K; +} + +int vgic_v2_has_attr_regs(struct kvm_device *dev, struct kvm_device_attr *attr) +{ + const struct vgic_register_region *region; + struct vgic_io_device iodev; + struct vgic_reg_attr reg_attr; + struct kvm_vcpu *vcpu; + gpa_t addr; + int ret; + + ret = vgic_v2_parse_attr(dev, attr, ®_attr); + if (ret) + return ret; + + vcpu = reg_attr.vcpu; + addr = reg_attr.addr; + + switch (attr->group) { + case KVM_DEV_ARM_VGIC_GRP_DIST_REGS: + iodev.regions = vgic_v2_dist_registers; + iodev.nr_regions = ARRAY_SIZE(vgic_v2_dist_registers); + iodev.base_addr = 0; + break; + case KVM_DEV_ARM_VGIC_GRP_CPU_REGS: + iodev.regions = vgic_v2_cpu_registers; + iodev.nr_regions = ARRAY_SIZE(vgic_v2_cpu_registers); + iodev.base_addr = 0; + break; + default: + return -ENXIO; + } + + /* We only support aligned 32-bit accesses. */ + if (addr & 3) + return -ENXIO; + + region = vgic_get_mmio_region(vcpu, &iodev, addr, sizeof(u32)); + if (!region) + return -ENXIO; + + return 0; +} + +int vgic_v2_cpuif_uaccess(struct kvm_vcpu *vcpu, bool is_write, + int offset, u32 *val) +{ + struct vgic_io_device dev = { + .regions = vgic_v2_cpu_registers, + .nr_regions = ARRAY_SIZE(vgic_v2_cpu_registers), + .iodev_type = IODEV_CPUIF, + }; + + return vgic_uaccess(vcpu, &dev, is_write, offset, val); +} + +int vgic_v2_dist_uaccess(struct kvm_vcpu *vcpu, bool is_write, + int offset, u32 *val) +{ + struct vgic_io_device dev = { + .regions = vgic_v2_dist_registers, + .nr_regions = ARRAY_SIZE(vgic_v2_dist_registers), + .iodev_type = IODEV_DIST, + }; + + return vgic_uaccess(vcpu, &dev, is_write, offset, val); +} |