// SPDX-License-Identifier: GPL-2.0-only
/*
 * VGICv3 MMIO handling functions
 */

#include <linux/bitfield.h>
#include <linux/irqchip/arm-gic-v3.h>
#include <linux/kvm.h>
#include <linux/kvm_host.h>
#include <linux/interrupt.h>
#include <kvm/iodev.h>
#include <kvm/arm_vgic.h>

#include <asm/kvm_emulate.h>
#include <asm/kvm_arm.h>
#include <asm/kvm_mmu.h>

#include "vgic.h"
#include "vgic-mmio.h"

/* extract @num bytes at @offset bytes offset in data */
unsigned long extract_bytes(u64 data, unsigned int offset,
                            unsigned int num)
{
        return (data >> (offset * 8)) & GENMASK_ULL(num * 8 - 1, 0);
}

/* allows updates of any half of a 64-bit register (or the whole thing) */
u64 update_64bit_reg(u64 reg, unsigned int offset, unsigned int len,
                     unsigned long val)
{
        int lower = (offset & 4) * 8;
        int upper = lower + 8 * len - 1;

        reg &= ~GENMASK_ULL(upper, lower);
        val &= GENMASK_ULL(len * 8 - 1, 0);

        return reg | ((u64)val << lower);
}

bool vgic_has_its(struct kvm *kvm)
{
        struct vgic_dist *dist = &kvm->arch.vgic;

        if (dist->vgic_model != KVM_DEV_TYPE_ARM_VGIC_V3)
                return false;

        return dist->has_its;
}

bool vgic_supports_direct_msis(struct kvm *kvm)
{
        /*
         * Deliberately conflate vLPI and vSGI support on GICv4.1 hardware,
         * indirectly allowing userspace to control whether or not vPEs are
         * allocated for the VM.
         */
        if (system_supports_direct_sgis() && !vgic_supports_direct_sgis(kvm))
                return false;

        return kvm_vgic_global_state.has_gicv4 && vgic_has_its(kvm);
}

bool system_supports_direct_sgis(void)
{
        return kvm_vgic_global_state.has_gicv4_1 && gic_cpuif_has_vsgi();
}

bool vgic_supports_direct_sgis(struct kvm *kvm)
{
        return kvm->arch.vgic.nassgicap;
}

/*
 * The Revision field in the IIDR have the following meanings:
 *
 * Revision 2: Interrupt groups are guest-configurable and signaled using
 *             their configured groups.
 */

static unsigned long vgic_mmio_read_v3_misc(struct kvm_vcpu *vcpu,
                                            gpa_t addr, unsigned int len)
{
        struct vgic_dist *vgic = &vcpu->kvm->arch.vgic;
        u32 value = 0;

        switch (addr & 0x0c) {
        case GICD_CTLR:
                if (vgic->enabled)
                        value |= GICD_CTLR_ENABLE_SS_G1;
                value |= GICD_CTLR_ARE_NS | GICD_CTLR_DS;
                if (vgic->nassgireq)
                        value |= GICD_CTLR_nASSGIreq;
                break;
        case GICD_TYPER:
                value = vgic->nr_spis + VGIC_NR_PRIVATE_IRQS;
                value = (value >> 5) - 1;
                if (vgic_has_its(vcpu->kvm)) {
                        value |= (INTERRUPT_ID_BITS_ITS - 1) << 19;
                        value |= GICD_TYPER_LPIS;
                } else {
                        value |= (INTERRUPT_ID_BITS_SPIS - 1) << 19;
                }
                break;
        case GICD_TYPER2:
                if (vgic_supports_direct_sgis(vcpu->kvm))
                        value = GICD_TYPER2_nASSGIcap;
                break;
        case GICD_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_v3_misc(struct kvm_vcpu *vcpu,
                                    gpa_t addr, unsigned int len,
                                    unsigned long val)
{
        struct vgic_dist *dist = &vcpu->kvm->arch.vgic;

        switch (addr & 0x0c) {
        case GICD_CTLR: {
                bool was_enabled, is_hwsgi;

                mutex_lock(&vcpu->kvm->arch.config_lock);

                was_enabled = dist->enabled;
                is_hwsgi = dist->nassgireq;

                dist->enabled = val & GICD_CTLR_ENABLE_SS_G1;

                /* Not a GICv4.1? No HW SGIs */
                if (!vgic_supports_direct_sgis(vcpu->kvm))
                        val &= ~GICD_CTLR_nASSGIreq;

                /* Dist stays enabled? nASSGIreq is RO */
                if (was_enabled && dist->enabled) {
                        val &= ~GICD_CTLR_nASSGIreq;
                        val |= FIELD_PREP(GICD_CTLR_nASSGIreq, is_hwsgi);
                }

                /* Switching HW SGIs? */
                dist->nassgireq = val & GICD_CTLR_nASSGIreq;
                if (is_hwsgi != dist->nassgireq)
                        vgic_v4_configure_vsgis(vcpu->kvm);

                if (vgic_supports_direct_sgis(vcpu->kvm) &&
                    was_enabled != dist->enabled)
                        kvm_make_all_cpus_request(vcpu->kvm, KVM_REQ_RELOAD_GICv4);
                else if (!was_enabled && dist->enabled)
                        vgic_kick_vcpus(vcpu->kvm);

                mutex_unlock(&vcpu->kvm->arch.config_lock);
                break;
        }
        case GICD_TYPER:
        case GICD_TYPER2:
        case GICD_IIDR:
                /* This is at best for documentation purposes... */
                return;
        }
}

static int vgic_mmio_uaccess_write_v3_misc(struct kvm_vcpu *vcpu,
                                           gpa_t addr, unsigned int len,
                                           unsigned long val)
{
        struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
        u32 reg;

        switch (addr & 0x0c) {
        case GICD_TYPER2:
                reg = vgic_mmio_read_v3_misc(vcpu, addr, len);

                if (reg == val)
                        return 0;
                if (vgic_initialized(vcpu->kvm))
                        return -EBUSY;
                if ((reg ^ val) & ~GICD_TYPER2_nASSGIcap)
                        return -EINVAL;
                if (!system_supports_direct_sgis() && val)
                        return -EINVAL;

                dist->nassgicap = val & GICD_TYPER2_nASSGIcap;
                return 0;
        case GICD_IIDR:
                reg = vgic_mmio_read_v3_misc(vcpu, addr, len);
                if ((reg ^ val) & ~GICD_IIDR_REVISION_MASK)
                        return -EINVAL;

                reg = FIELD_GET(GICD_IIDR_REVISION_MASK, reg);
                switch (reg) {
                case KVM_VGIC_IMP_REV_2:
                case KVM_VGIC_IMP_REV_3:
                        dist->implementation_rev = reg;
                        return 0;
                default:
                        return -EINVAL;
                }
        case GICD_CTLR:
                /* Not a GICv4.1? No HW SGIs */
                if (!vgic_supports_direct_sgis(vcpu->kvm))
                        val &= ~GICD_CTLR_nASSGIreq;

                dist->enabled = val & GICD_CTLR_ENABLE_SS_G1;
                dist->nassgireq = val & GICD_CTLR_nASSGIreq;
                return 0;
        }

        vgic_mmio_write_v3_misc(vcpu, addr, len, val);
        return 0;
}

static unsigned long vgic_mmio_read_irouter(struct kvm_vcpu *vcpu,
                                            gpa_t addr, unsigned int len)
{
        int intid = VGIC_ADDR_TO_INTID(addr, 64);
        struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, intid);
        unsigned long ret = 0;

        if (!irq)
                return 0;

        /* The upper word is RAZ for us. */
        if (!(addr & 4))
                ret = extract_bytes(READ_ONCE(irq->mpidr), addr & 7, len);

        vgic_put_irq(vcpu->kvm, irq);
        return ret;
}

static void vgic_mmio_write_irouter(struct kvm_vcpu *vcpu,
                                    gpa_t addr, unsigned int len,
                                    unsigned long val)
{
        int intid = VGIC_ADDR_TO_INTID(addr, 64);
        struct vgic_irq *irq;
        unsigned long flags;

        /* The upper word is WI for us since we don't implement Aff3. */
        if (addr & 4)
                return;

        irq = vgic_get_irq(vcpu->kvm, intid);

        if (!irq)
                return;

        raw_spin_lock_irqsave(&irq->irq_lock, flags);

        /* We only care about and preserve Aff0, Aff1 and Aff2. */
        irq->mpidr = val & GENMASK(23, 0);
        irq->target_vcpu = kvm_mpidr_to_vcpu(vcpu->kvm, irq->mpidr);

        raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
        vgic_put_irq(vcpu->kvm, irq);
}

bool vgic_lpis_enabled(struct kvm_vcpu *vcpu)
{
        struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;

        return atomic_read(&vgic_cpu->ctlr) == GICR_CTLR_ENABLE_LPIS;
}

static unsigned long vgic_mmio_read_v3r_ctlr(struct kvm_vcpu *vcpu,
                                             gpa_t addr, unsigned int len)
{
        struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
        unsigned long val;

        val = atomic_read(&vgic_cpu->ctlr);
        if (vgic_get_implementation_rev(vcpu) >= KVM_VGIC_IMP_REV_3)
                val |= GICR_CTLR_IR | GICR_CTLR_CES;

        return val;
}

static void vgic_mmio_write_v3r_ctlr(struct kvm_vcpu *vcpu,
                                     gpa_t addr, unsigned int len,
                                     unsigned long val)
{
        struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
        u32 ctlr;

        if (!vgic_has_its(vcpu->kvm))
                return;

        if (!(val & GICR_CTLR_ENABLE_LPIS)) {
                /*
                 * Don't disable if RWP is set, as there already an
                 * ongoing disable. Funky guest...
                 */
                ctlr = atomic_cmpxchg_acquire(&vgic_cpu->ctlr,
                                              GICR_CTLR_ENABLE_LPIS,
                                              GICR_CTLR_RWP);
                if (ctlr != GICR_CTLR_ENABLE_LPIS)
                        return;

                vgic_flush_pending_lpis(vcpu);
                vgic_its_invalidate_all_caches(vcpu->kvm);
                atomic_set_release(&vgic_cpu->ctlr, 0);
        } else {
                ctlr = atomic_cmpxchg_acquire(&vgic_cpu->ctlr, 0,
                                              GICR_CTLR_ENABLE_LPIS);
                if (ctlr != 0)
                        return;

                vgic_enable_lpis(vcpu);
        }
}

static bool vgic_mmio_vcpu_rdist_is_last(struct kvm_vcpu *vcpu)
{
        struct vgic_dist *vgic = &vcpu->kvm->arch.vgic;
        struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
        struct vgic_redist_region *iter, *rdreg = vgic_cpu->rdreg;

        if (!rdreg)
                return false;

        if (vgic_cpu->rdreg_index < rdreg->free_index - 1) {
                return false;
        } else if (rdreg->count && vgic_cpu->rdreg_index == (rdreg->count - 1)) {
                struct list_head *rd_regions = &vgic->rd_regions;
                gpa_t end = rdreg->base + rdreg->count * KVM_VGIC_V3_REDIST_SIZE;

                /*
                 * the rdist is the last one of the redist region,
                 * check whether there is no other contiguous rdist region
                 */
                list_for_each_entry(iter, rd_regions, list) {
                        if (iter->base == end && iter->free_index > 0)
                                return false;
                }
        }
        return true;
}

static unsigned long vgic_mmio_read_v3r_typer(struct kvm_vcpu *vcpu,
                                              gpa_t addr, unsigned int len)
{
        unsigned long mpidr = kvm_vcpu_get_mpidr_aff(vcpu);
        int target_vcpu_id = vcpu->vcpu_id;
        u64 value;

        value = (u64)(mpidr & GENMASK(23, 0)) << 32;
        value |= ((target_vcpu_id & 0xffff) << 8);

        if (vgic_has_its(vcpu->kvm))
                value |= GICR_TYPER_PLPIS;

        if (vgic_mmio_vcpu_rdist_is_last(vcpu))
                value |= GICR_TYPER_LAST;

        return extract_bytes(value, addr & 7, len);
}

static unsigned long vgic_mmio_read_v3r_iidr(struct kvm_vcpu *vcpu,
                                             gpa_t addr, unsigned int len)
{
        return (PRODUCT_ID_KVM << 24) | (IMPLEMENTER_ARM << 0);
}

static unsigned long vgic_mmio_read_v3_idregs(struct kvm_vcpu *vcpu,
                                              gpa_t addr, unsigned int len)
{
        switch (addr & 0xffff) {
        case GICD_PIDR2:
                /* report a GICv3 compliant implementation */
                return 0x3b;
        }

        return 0;
}

static int vgic_v3_uaccess_write_pending(struct kvm_vcpu *vcpu,
                                         gpa_t addr, unsigned int len,
                                         unsigned long val)
{
        int ret;

        ret = vgic_uaccess_write_spending(vcpu, addr, len, val);
        if (ret)
                return ret;

        return vgic_uaccess_write_cpending(vcpu, addr, len, ~val);
}

/* We want to avoid outer shareable. */
u64 vgic_sanitise_shareability(u64 field)
{
        switch (field) {
        case GIC_BASER_OuterShareable:
                return GIC_BASER_InnerShareable;
        default:
                return field;
        }
}

/* Avoid any inner non-cacheable mapping. */
u64 vgic_sanitise_inner_cacheability(u64 field)
{
        switch (field) {
        case GIC_BASER_CACHE_nCnB:
        case GIC_BASER_CACHE_nC:
                return GIC_BASER_CACHE_RaWb;
        default:
                return field;
        }
}

/* Non-cacheable or same-as-inner are OK. */
u64 vgic_sanitise_outer_cacheability(u64 field)
{
        switch (field) {
        case GIC_BASER_CACHE_SameAsInner:
        case GIC_BASER_CACHE_nC:
                return field;
        default:
                return GIC_BASER_CACHE_SameAsInner;
        }
}

u64 vgic_sanitise_field(u64 reg, u64 field_mask, int field_shift,
                        u64 (*sanitise_fn)(u64))
{
        u64 field = (reg & field_mask) >> field_shift;

        field = sanitise_fn(field) << field_shift;
        return (reg & ~field_mask) | field;
}

#define PROPBASER_RES0_MASK                                             \
        (GENMASK_ULL(63, 59) | GENMASK_ULL(55, 52) | GENMASK_ULL(6, 5))
#define PENDBASER_RES0_MASK                                             \
        (BIT_ULL(63) | GENMASK_ULL(61, 59) | GENMASK_ULL(55, 52) |      \
         GENMASK_ULL(15, 12) | GENMASK_ULL(6, 0))

static u64 vgic_sanitise_pendbaser(u64 reg)
{
        reg = vgic_sanitise_field(reg, GICR_PENDBASER_SHAREABILITY_MASK,
                                  GICR_PENDBASER_SHAREABILITY_SHIFT,
                                  vgic_sanitise_shareability);
        reg = vgic_sanitise_field(reg, GICR_PENDBASER_INNER_CACHEABILITY_MASK,
                                  GICR_PENDBASER_INNER_CACHEABILITY_SHIFT,
                                  vgic_sanitise_inner_cacheability);
        reg = vgic_sanitise_field(reg, GICR_PENDBASER_OUTER_CACHEABILITY_MASK,
                                  GICR_PENDBASER_OUTER_CACHEABILITY_SHIFT,
                                  vgic_sanitise_outer_cacheability);

        reg &= ~PENDBASER_RES0_MASK;

        return reg;
}

static u64 vgic_sanitise_propbaser(u64 reg)
{
        reg = vgic_sanitise_field(reg, GICR_PROPBASER_SHAREABILITY_MASK,
                                  GICR_PROPBASER_SHAREABILITY_SHIFT,
                                  vgic_sanitise_shareability);
        reg = vgic_sanitise_field(reg, GICR_PROPBASER_INNER_CACHEABILITY_MASK,
                                  GICR_PROPBASER_INNER_CACHEABILITY_SHIFT,
                                  vgic_sanitise_inner_cacheability);
        reg = vgic_sanitise_field(reg, GICR_PROPBASER_OUTER_CACHEABILITY_MASK,
                                  GICR_PROPBASER_OUTER_CACHEABILITY_SHIFT,
                                  vgic_sanitise_outer_cacheability);

        reg &= ~PROPBASER_RES0_MASK;
        return reg;
}

static unsigned long vgic_mmio_read_propbase(struct kvm_vcpu *vcpu,
                                             gpa_t addr, unsigned int len)
{
        struct vgic_dist *dist = &vcpu->kvm->arch.vgic;

        return extract_bytes(dist->propbaser, addr & 7, len);
}

static void vgic_mmio_write_propbase(struct kvm_vcpu *vcpu,
                                     gpa_t addr, unsigned int len,
                                     unsigned long val)
{
        struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
        u64 old_propbaser, propbaser;

        /* Storing a value with LPIs already enabled is undefined */
        if (vgic_lpis_enabled(vcpu))
                return;

        do {
                old_propbaser = READ_ONCE(dist->propbaser);
                propbaser = old_propbaser;
                propbaser = update_64bit_reg(propbaser, addr & 4, len, val);
                propbaser = vgic_sanitise_propbaser(propbaser);
        } while (cmpxchg64(&dist->propbaser, old_propbaser,
                           propbaser) != old_propbaser);
}

static unsigned long vgic_mmio_read_pendbase(struct kvm_vcpu *vcpu,
                                             gpa_t addr, unsigned int len)
{
        struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
        u64 value = vgic_cpu->pendbaser;

        value &= ~GICR_PENDBASER_PTZ;

        return extract_bytes(value, addr & 7, len);
}

static void vgic_mmio_write_pendbase(struct kvm_vcpu *vcpu,
                                     gpa_t addr, unsigned int len,
                                     unsigned long val)
{
        struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
        u64 old_pendbaser, pendbaser;

        /* Storing a value with LPIs already enabled is undefined */
        if (vgic_lpis_enabled(vcpu))
                return;

        do {
                old_pendbaser = READ_ONCE(vgic_cpu->pendbaser);
                pendbaser = old_pendbaser;
                pendbaser = update_64bit_reg(pendbaser, addr & 4, len, val);
                pendbaser = vgic_sanitise_pendbaser(pendbaser);
        } while (cmpxchg64(&vgic_cpu->pendbaser, old_pendbaser,
                           pendbaser) != old_pendbaser);
}

static unsigned long vgic_mmio_read_sync(struct kvm_vcpu *vcpu,
                                         gpa_t addr, unsigned int len)
{
        return !!atomic_read(&vcpu->arch.vgic_cpu.syncr_busy);
}

static void vgic_set_rdist_busy(struct kvm_vcpu *vcpu, bool busy)
{
        if (busy) {
                atomic_inc(&vcpu->arch.vgic_cpu.syncr_busy);
                smp_mb__after_atomic();
        } else {
                smp_mb__before_atomic();
                atomic_dec(&vcpu->arch.vgic_cpu.syncr_busy);
        }
}

static void vgic_mmio_write_invlpi(struct kvm_vcpu *vcpu,
                                   gpa_t addr, unsigned int len,
                                   unsigned long val)
{
        struct vgic_irq *irq;
        u32 intid;

        /*
         * If the guest wrote only to the upper 32bit part of the
         * register, drop the write on the floor, as it is only for
         * vPEs (which we don't support for obvious reasons).
         *
         * Also discard the access if LPIs are not enabled.
         */
        if ((addr & 4) || !vgic_lpis_enabled(vcpu))
                return;

        intid = lower_32_bits(val);
        if (intid < VGIC_MIN_LPI)
                return;

        vgic_set_rdist_busy(vcpu, true);

        irq = vgic_get_irq(vcpu->kvm, intid);
        if (irq) {
                vgic_its_inv_lpi(vcpu->kvm, irq);
                vgic_put_irq(vcpu->kvm, irq);
        }

        vgic_set_rdist_busy(vcpu, false);
}

static void vgic_mmio_write_invall(struct kvm_vcpu *vcpu,
                                   gpa_t addr, unsigned int len,
                                   unsigned long val)
{
        /* See vgic_mmio_write_invlpi() for the early return rationale */
        if ((addr & 4) || !vgic_lpis_enabled(vcpu))
                return;

        vgic_set_rdist_busy(vcpu, true);
        vgic_its_invall(vcpu);
        vgic_set_rdist_busy(vcpu, false);
}

/*
 * The GICv3 per-IRQ registers are split to control PPIs and SGIs in the
 * redistributors, while SPIs are covered by registers in the distributor
 * block. Trying to set private IRQs in this block gets ignored.
 * We take some special care here to fix the calculation of the register
 * offset.
 */
#define REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(off, rd, wr, ur, uw, bpi, acc) \
        {                                                               \
                .reg_offset = off,                                      \
                .bits_per_irq = bpi,                                    \
                .len = (bpi * VGIC_NR_PRIVATE_IRQS) / 8,                \
                .access_flags = acc,                                    \
                .read = vgic_mmio_read_raz,                             \
                .write = vgic_mmio_write_wi,                            \
        }, {                                                            \
                .reg_offset = off + (bpi * VGIC_NR_PRIVATE_IRQS) / 8,   \
                .bits_per_irq = bpi,                                    \
                .len = (bpi * (1024 - VGIC_NR_PRIVATE_IRQS)) / 8,       \
                .access_flags = acc,                                    \
                .read = rd,                                             \
                .write = wr,                                            \
                .uaccess_read = ur,                                     \
                .uaccess_write = uw,                                    \
        }

static const struct vgic_register_region vgic_v3_dist_registers[] = {
        REGISTER_DESC_WITH_LENGTH_UACCESS(GICD_CTLR,
                vgic_mmio_read_v3_misc, vgic_mmio_write_v3_misc,
                NULL, vgic_mmio_uaccess_write_v3_misc,
                16, VGIC_ACCESS_32bit),
        REGISTER_DESC_WITH_LENGTH(GICD_STATUSR,
                vgic_mmio_read_rao, vgic_mmio_write_wi, 4,
                VGIC_ACCESS_32bit),
        REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(GICD_IGROUPR,
                vgic_mmio_read_group, vgic_mmio_write_group, NULL, NULL, 1,
                VGIC_ACCESS_32bit),
        REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(GICD_ISENABLER,
                vgic_mmio_read_enable, vgic_mmio_write_senable,
                NULL, vgic_uaccess_write_senable, 1,
                VGIC_ACCESS_32bit),
        REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(GICD_ICENABLER,
                vgic_mmio_read_enable, vgic_mmio_write_cenable,
               NULL, vgic_uaccess_write_cenable, 1,
                VGIC_ACCESS_32bit),
        REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(GICD_ISPENDR,
                vgic_mmio_read_pending, vgic_mmio_write_spending,
                vgic_uaccess_read_pending, vgic_v3_uaccess_write_pending, 1,
                VGIC_ACCESS_32bit),
        REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(GICD_ICPENDR,
                vgic_mmio_read_pending, vgic_mmio_write_cpending,
                vgic_mmio_read_raz, vgic_mmio_uaccess_write_wi, 1,
                VGIC_ACCESS_32bit),
        REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(GICD_ISACTIVER,
                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_SHARED(GICD_ICACTIVER,
                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_SHARED(GICD_IPRIORITYR,
                vgic_mmio_read_priority, vgic_mmio_write_priority, NULL, NULL,
                8, VGIC_ACCESS_32bit | VGIC_ACCESS_8bit),
        REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(GICD_ITARGETSR,
                vgic_mmio_read_raz, vgic_mmio_write_wi, NULL, NULL, 8,
                VGIC_ACCESS_32bit | VGIC_ACCESS_8bit),
        REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(GICD_ICFGR,
                vgic_mmio_read_config, vgic_mmio_write_config, NULL, NULL, 2,
                VGIC_ACCESS_32bit),
        REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(GICD_IGRPMODR,
                vgic_mmio_read_raz, vgic_mmio_write_wi, NULL, NULL, 1,
                VGIC_ACCESS_32bit),
        REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(GICD_IROUTER,
                vgic_mmio_read_irouter, vgic_mmio_write_irouter, NULL, NULL, 64,
                VGIC_ACCESS_64bit | VGIC_ACCESS_32bit),
        REGISTER_DESC_WITH_LENGTH(GICD_IDREGS,
                vgic_mmio_read_v3_idregs, vgic_mmio_write_wi, 48,
                VGIC_ACCESS_32bit),
};

static const struct vgic_register_region vgic_v3_rd_registers[] = {
        /* RD_base registers */
        REGISTER_DESC_WITH_LENGTH(GICR_CTLR,
                vgic_mmio_read_v3r_ctlr, vgic_mmio_write_v3r_ctlr, 4,
                VGIC_ACCESS_32bit),
        REGISTER_DESC_WITH_LENGTH(GICR_STATUSR,
                vgic_mmio_read_raz, vgic_mmio_write_wi, 4,
                VGIC_ACCESS_32bit),
        REGISTER_DESC_WITH_LENGTH(GICR_IIDR,
                vgic_mmio_read_v3r_iidr, vgic_mmio_write_wi, 4,
                VGIC_ACCESS_32bit),
        REGISTER_DESC_WITH_LENGTH_UACCESS(GICR_TYPER,
                vgic_mmio_read_v3r_typer, vgic_mmio_write_wi,
                NULL, vgic_mmio_uaccess_write_wi, 8,
                VGIC_ACCESS_64bit | VGIC_ACCESS_32bit),
        REGISTER_DESC_WITH_LENGTH(GICR_WAKER,
                vgic_mmio_read_raz, vgic_mmio_write_wi, 4,
                VGIC_ACCESS_32bit),
        REGISTER_DESC_WITH_LENGTH(GICR_PROPBASER,
                vgic_mmio_read_propbase, vgic_mmio_write_propbase, 8,
                VGIC_ACCESS_64bit | VGIC_ACCESS_32bit),
        REGISTER_DESC_WITH_LENGTH(GICR_PENDBASER,
                vgic_mmio_read_pendbase, vgic_mmio_write_pendbase, 8,
                VGIC_ACCESS_64bit | VGIC_ACCESS_32bit),
        REGISTER_DESC_WITH_LENGTH(GICR_INVLPIR,
                vgic_mmio_read_raz, vgic_mmio_write_invlpi, 8,
                VGIC_ACCESS_64bit | VGIC_ACCESS_32bit),
        REGISTER_DESC_WITH_LENGTH(GICR_INVALLR,
                vgic_mmio_read_raz, vgic_mmio_write_invall, 8,
                VGIC_ACCESS_64bit | VGIC_ACCESS_32bit),
        REGISTER_DESC_WITH_LENGTH(GICR_SYNCR,
                vgic_mmio_read_sync, vgic_mmio_write_wi, 4,
                VGIC_ACCESS_32bit),
        REGISTER_DESC_WITH_LENGTH(GICR_IDREGS,
                vgic_mmio_read_v3_idregs, vgic_mmio_write_wi, 48,
                VGIC_ACCESS_32bit),
        /* SGI_base registers */
        REGISTER_DESC_WITH_LENGTH(SZ_64K + GICR_IGROUPR0,
                vgic_mmio_read_group, vgic_mmio_write_group, 4,
                VGIC_ACCESS_32bit),
        REGISTER_DESC_WITH_LENGTH_UACCESS(SZ_64K + GICR_ISENABLER0,
                vgic_mmio_read_enable, vgic_mmio_write_senable,
                NULL, vgic_uaccess_write_senable, 4,
                VGIC_ACCESS_32bit),
        REGISTER_DESC_WITH_LENGTH_UACCESS(SZ_64K + GICR_ICENABLER0,
                vgic_mmio_read_enable, vgic_mmio_write_cenable,
                NULL, vgic_uaccess_write_cenable, 4,
                VGIC_ACCESS_32bit),
        REGISTER_DESC_WITH_LENGTH_UACCESS(SZ_64K + GICR_ISPENDR0,
                vgic_mmio_read_pending, vgic_mmio_write_spending,
                vgic_uaccess_read_pending, vgic_v3_uaccess_write_pending, 4,
                VGIC_ACCESS_32bit),
        REGISTER_DESC_WITH_LENGTH_UACCESS(SZ_64K + GICR_ICPENDR0,
                vgic_mmio_read_pending, vgic_mmio_write_cpending,
                vgic_mmio_read_raz, vgic_mmio_uaccess_write_wi, 4,
                VGIC_ACCESS_32bit),
        REGISTER_DESC_WITH_LENGTH_UACCESS(SZ_64K + GICR_ISACTIVER0,
                vgic_mmio_read_active, vgic_mmio_write_sactive,
                vgic_uaccess_read_active, vgic_mmio_uaccess_write_sactive, 4,
                VGIC_ACCESS_32bit),
        REGISTER_DESC_WITH_LENGTH_UACCESS(SZ_64K + GICR_ICACTIVER0,
                vgic_mmio_read_active, vgic_mmio_write_cactive,
                vgic_uaccess_read_active, vgic_mmio_uaccess_write_cactive, 4,
                VGIC_ACCESS_32bit),
        REGISTER_DESC_WITH_LENGTH(SZ_64K + GICR_IPRIORITYR0,
                vgic_mmio_read_priority, vgic_mmio_write_priority, 32,
                VGIC_ACCESS_32bit | VGIC_ACCESS_8bit),
        REGISTER_DESC_WITH_LENGTH(SZ_64K + GICR_ICFGR0,
                vgic_mmio_read_config, vgic_mmio_write_config, 8,
                VGIC_ACCESS_32bit),
        REGISTER_DESC_WITH_LENGTH(SZ_64K + GICR_IGRPMODR0,
                vgic_mmio_read_raz, vgic_mmio_write_wi, 4,
                VGIC_ACCESS_32bit),
        REGISTER_DESC_WITH_LENGTH(SZ_64K + GICR_NSACR,
                vgic_mmio_read_raz, vgic_mmio_write_wi, 4,
                VGIC_ACCESS_32bit),
};

unsigned int vgic_v3_init_dist_iodev(struct vgic_io_device *dev)
{
        dev->regions = vgic_v3_dist_registers;
        dev->nr_regions = ARRAY_SIZE(vgic_v3_dist_registers);

        kvm_iodevice_init(&dev->dev, &kvm_io_gic_ops);

        return SZ_64K;
}

/**
 * vgic_register_redist_iodev - register a single redist iodev
 * @vcpu:    The VCPU to which the redistributor belongs
 *
 * Register a KVM iodev for this VCPU's redistributor using the address
 * provided.
 *
 * Return 0 on success, -ERRNO otherwise.
 */
int vgic_register_redist_iodev(struct kvm_vcpu *vcpu)
{
        struct kvm *kvm = vcpu->kvm;
        struct vgic_dist *vgic = &kvm->arch.vgic;
        struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
        struct vgic_io_device *rd_dev = &vcpu->arch.vgic_cpu.rd_iodev;
        struct vgic_redist_region *rdreg;
        gpa_t rd_base;
        int ret = 0;

        lockdep_assert_held(&kvm->slots_lock);
        mutex_lock(&kvm->arch.config_lock);

        if (!IS_VGIC_ADDR_UNDEF(vgic_cpu->rd_iodev.base_addr))
                goto out_unlock;

        /*
         * We may be creating VCPUs before having set the base address for the
         * redistributor region, in which case we will come back to this
         * function for all VCPUs when the base address is set.  Just return
         * without doing any work for now.
         */
        rdreg = vgic_v3_rdist_free_slot(&vgic->rd_regions);
        if (!rdreg)
                goto out_unlock;

        if (!vgic_v3_check_base(kvm)) {
                ret = -EINVAL;
                goto out_unlock;
        }

        vgic_cpu->rdreg = rdreg;
        vgic_cpu->rdreg_index = rdreg->free_index;

        rd_base = rdreg->base + rdreg->free_index * KVM_VGIC_V3_REDIST_SIZE;

        kvm_iodevice_init(&rd_dev->dev, &kvm_io_gic_ops);
        rd_dev->base_addr = rd_base;
        rd_dev->iodev_type = IODEV_REDIST;
        rd_dev->regions = vgic_v3_rd_registers;
        rd_dev->nr_regions = ARRAY_SIZE(vgic_v3_rd_registers);
        rd_dev->redist_vcpu = vcpu;

        mutex_unlock(&kvm->arch.config_lock);

        ret = kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS, rd_base,
                                      2 * SZ_64K, &rd_dev->dev);
        if (ret)
                return ret;

        /* Protected by slots_lock */
        rdreg->free_index++;
        return 0;

out_unlock:
        mutex_unlock(&kvm->arch.config_lock);
        return ret;
}

void vgic_unregister_redist_iodev(struct kvm_vcpu *vcpu)
{
        struct vgic_io_device *rd_dev = &vcpu->arch.vgic_cpu.rd_iodev;

        kvm_io_bus_unregister_dev(vcpu->kvm, KVM_MMIO_BUS, &rd_dev->dev);
}

static int vgic_register_all_redist_iodevs(struct kvm *kvm)
{
        struct kvm_vcpu *vcpu;
        unsigned long c;
        int ret = 0;

        lockdep_assert_held(&kvm->slots_lock);

        kvm_for_each_vcpu(c, vcpu, kvm) {
                ret = vgic_register_redist_iodev(vcpu);
                if (ret)
                        break;
        }

        if (ret) {
                /* The current c failed, so iterate over the previous ones. */
                int i;

                for (i = 0; i < c; i++) {
                        vcpu = kvm_get_vcpu(kvm, i);
                        vgic_unregister_redist_iodev(vcpu);
                }
        }

        return ret;
}

/**
 * vgic_v3_alloc_redist_region - Allocate a new redistributor region
 *
 * Performs various checks before inserting the rdist region in the list.
 * Those tests depend on whether the size of the rdist region is known
 * (ie. count != 0). The list is sorted by rdist region index.
 *
 * @kvm: kvm handle
 * @index: redist region index
 * @base: base of the new rdist region
 * @count: number of redistributors the region is made of (0 in the old style
 * single region, whose size is induced from the number of vcpus)
 *
 * Return 0 on success, < 0 otherwise
 */
static int vgic_v3_alloc_redist_region(struct kvm *kvm, uint32_t index,
                                       gpa_t base, uint32_t count)
{
        struct vgic_dist *d = &kvm->arch.vgic;
        struct vgic_redist_region *rdreg;
        struct list_head *rd_regions = &d->rd_regions;
        int nr_vcpus = atomic_read(&kvm->online_vcpus);
        size_t size = count ? count * KVM_VGIC_V3_REDIST_SIZE
                            : nr_vcpus * KVM_VGIC_V3_REDIST_SIZE;
        int ret;

        /* cross the end of memory ? */
        if (base + size < base)
                return -EINVAL;

        if (list_empty(rd_regions)) {
                if (index != 0)
                        return -EINVAL;
        } else {
                rdreg = list_last_entry(rd_regions,
                                        struct vgic_redist_region, list);

                /* Don't mix single region and discrete redist regions */
                if (!count && rdreg->count)
                        return -EINVAL;

                if (!count)
                        return -EEXIST;

                if (index != rdreg->index + 1)
                        return -EINVAL;
        }

        /*
         * For legacy single-region redistributor regions (!count),
         * check that the redistributor region does not overlap with the
         * distributor's address space.
         */
        if (!count && !IS_VGIC_ADDR_UNDEF(d->vgic_dist_base) &&
                vgic_dist_overlap(kvm, base, size))
                return -EINVAL;

        /* collision with any other rdist region? */
        if (vgic_v3_rdist_overlap(kvm, base, size))
                return -EINVAL;

        rdreg = kzalloc_obj(*rdreg, GFP_KERNEL_ACCOUNT);
        if (!rdreg)
                return -ENOMEM;

        rdreg->base = VGIC_ADDR_UNDEF;

        ret = vgic_check_iorange(kvm, rdreg->base, base, SZ_64K, size);
        if (ret)
                goto free;

        rdreg->base = base;
        rdreg->count = count;
        rdreg->free_index = 0;
        rdreg->index = index;

        list_add_tail(&rdreg->list, rd_regions);
        return 0;
free:
        kfree(rdreg);
        return ret;
}

void vgic_v3_free_redist_region(struct kvm *kvm, struct vgic_redist_region *rdreg)
{
        struct kvm_vcpu *vcpu;
        unsigned long c;

        lockdep_assert_held(&kvm->arch.config_lock);

        /* Garbage collect the region */
        kvm_for_each_vcpu(c, vcpu, kvm) {
                if (vcpu->arch.vgic_cpu.rdreg == rdreg)
                        vcpu->arch.vgic_cpu.rdreg = NULL;
        }

        list_del(&rdreg->list);
        kfree(rdreg);
}

int vgic_v3_set_redist_base(struct kvm *kvm, u32 index, u64 addr, u32 count)
{
        int ret;

        mutex_lock(&kvm->arch.config_lock);
        ret = vgic_v3_alloc_redist_region(kvm, index, addr, count);
        mutex_unlock(&kvm->arch.config_lock);
        if (ret)
                return ret;

        /*
         * Register iodevs for each existing VCPU.  Adding more VCPUs
         * afterwards will register the iodevs when needed.
         */
        ret = vgic_register_all_redist_iodevs(kvm);
        if (ret) {
                struct vgic_redist_region *rdreg;

                mutex_lock(&kvm->arch.config_lock);
                rdreg = vgic_v3_rdist_region_from_index(kvm, index);
                vgic_v3_free_redist_region(kvm, rdreg);
                mutex_unlock(&kvm->arch.config_lock);
                return ret;
        }

        return 0;
}

int vgic_v3_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_v3_parse_attr(dev, attr, &reg_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_v3_dist_registers;
                iodev.nr_regions = ARRAY_SIZE(vgic_v3_dist_registers);
                iodev.base_addr = 0;
                break;
        case KVM_DEV_ARM_VGIC_GRP_REDIST_REGS:{
                iodev.regions = vgic_v3_rd_registers;
                iodev.nr_regions = ARRAY_SIZE(vgic_v3_rd_registers);
                iodev.base_addr = 0;
                break;
        }
        case KVM_DEV_ARM_VGIC_GRP_CPU_SYSREGS:
                return vgic_v3_has_cpu_sysregs_attr(vcpu, attr);
        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;
}

/*
 * The ICC_SGI* registers encode the affinity differently from the MPIDR,
 * so provide a wrapper to use the existing defines to isolate a certain
 * affinity level.
 */
#define SGI_AFFINITY_LEVEL(reg, level) \
        ((((reg) & ICC_SGI1R_AFFINITY_## level ##_MASK) \
        >> ICC_SGI1R_AFFINITY_## level ##_SHIFT) << MPIDR_LEVEL_SHIFT(level))

static void vgic_v3_queue_sgi(struct kvm_vcpu *vcpu, u32 sgi, bool allow_group1)
{
        struct vgic_irq *irq = vgic_get_vcpu_irq(vcpu, sgi);
        unsigned long flags;

        raw_spin_lock_irqsave(&irq->irq_lock, flags);

        /*
         * An access targeting Group0 SGIs can only generate
         * those, while an access targeting Group1 SGIs can
         * generate interrupts of either group.
         */
        if (!irq->group || allow_group1) {
                if (!irq->hw) {
                        irq->pending_latch = true;
                        vgic_queue_irq_unlock(vcpu->kvm, irq, flags);
                } else {
                        /* HW SGI? Ask the GIC to inject it */
                        int err;
                        err = irq_set_irqchip_state(irq->host_irq,
                                                    IRQCHIP_STATE_PENDING,
                                                    true);
                        WARN_RATELIMIT(err, "IRQ %d", irq->host_irq);
                        raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
                }
        } else {
                raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
        }

        vgic_put_irq(vcpu->kvm, irq);
}

/**
 * vgic_v3_dispatch_sgi - handle SGI requests from VCPUs
 * @vcpu: The VCPU requesting a SGI
 * @reg: The value written into ICC_{ASGI1,SGI0,SGI1}R by that VCPU
 * @allow_group1: Does the sysreg access allow generation of G1 SGIs
 *
 * With GICv3 (and ARE=1) CPUs trigger SGIs by writing to a system register.
 * This will trap in sys_regs.c and call this function.
 * This ICC_SGI1R_EL1 register contains the upper three affinity levels of the
 * target processors as well as a bitmask of 16 Aff0 CPUs.
 *
 * If the interrupt routing mode bit is not set, we iterate over the Aff0
 * bits and signal the VCPUs matching the provided Aff{3,2,1}.
 *
 * If this bit is set, we signal all, but not the calling VCPU.
 */
void vgic_v3_dispatch_sgi(struct kvm_vcpu *vcpu, u64 reg, bool allow_group1)
{
        struct kvm *kvm = vcpu->kvm;
        struct kvm_vcpu *c_vcpu;
        unsigned long target_cpus;
        u64 mpidr;
        u32 sgi, aff0;
        unsigned long c;

        sgi = FIELD_GET(ICC_SGI1R_SGI_ID_MASK, reg);

        /* Broadcast */
        if (unlikely(reg & BIT_ULL(ICC_SGI1R_IRQ_ROUTING_MODE_BIT))) {
                kvm_for_each_vcpu(c, c_vcpu, kvm) {
                        /* Don't signal the calling VCPU */
                        if (c_vcpu == vcpu)
                                continue;

                        vgic_v3_queue_sgi(c_vcpu, sgi, allow_group1);
                }

                return;
        }

        /* We iterate over affinities to find the corresponding vcpus */
        mpidr = SGI_AFFINITY_LEVEL(reg, 3);
        mpidr |= SGI_AFFINITY_LEVEL(reg, 2);
        mpidr |= SGI_AFFINITY_LEVEL(reg, 1);
        target_cpus = FIELD_GET(ICC_SGI1R_TARGET_LIST_MASK, reg);

        for_each_set_bit(aff0, &target_cpus, hweight_long(ICC_SGI1R_TARGET_LIST_MASK)) {
                c_vcpu = kvm_mpidr_to_vcpu(kvm, mpidr | aff0);
                if (c_vcpu)
                        vgic_v3_queue_sgi(c_vcpu, sgi, allow_group1);
        }
}

int vgic_v3_dist_uaccess(struct kvm_vcpu *vcpu, bool is_write,
                         int offset, u32 *val)
{
        struct vgic_io_device dev = {
                .regions = vgic_v3_dist_registers,
                .nr_regions = ARRAY_SIZE(vgic_v3_dist_registers),
        };

        return vgic_uaccess(vcpu, &dev, is_write, offset, val);
}

int vgic_v3_redist_uaccess(struct kvm_vcpu *vcpu, bool is_write,
                           int offset, u32 *val)
{
        struct vgic_io_device rd_dev = {
                .regions = vgic_v3_rd_registers,
                .nr_regions = ARRAY_SIZE(vgic_v3_rd_registers),
        };

        return vgic_uaccess(vcpu, &rd_dev, is_write, offset, val);
}

int vgic_v3_line_level_info_uaccess(struct kvm_vcpu *vcpu, bool is_write,
                                    u32 intid, u32 *val)
{
        if (intid % 32)
                return -EINVAL;

        if (is_write)
                vgic_write_irq_line_level_info(vcpu, intid, *val);
        else
                *val = vgic_read_irq_line_level_info(vcpu, intid);

        return 0;
}