root/arch/s390/kvm/interrupt.c
// SPDX-License-Identifier: GPL-2.0
/*
 * handling kvm guest interrupts
 *
 * Copyright IBM Corp. 2008, 2020
 *
 *    Author(s): Carsten Otte <cotte@de.ibm.com>
 */

#define pr_fmt(fmt) "kvm-s390: " fmt

#include <linux/cpufeature.h>
#include <linux/interrupt.h>
#include <linux/kvm_host.h>
#include <linux/hrtimer.h>
#include <linux/export.h>
#include <linux/mmu_context.h>
#include <linux/nospec.h>
#include <linux/signal.h>
#include <linux/slab.h>
#include <linux/bitmap.h>
#include <linux/vmalloc.h>
#include <asm/access-regs.h>
#include <asm/asm-offsets.h>
#include <asm/dis.h>
#include <linux/uaccess.h>
#include <asm/sclp.h>
#include <asm/isc.h>
#include <asm/nmi.h>
#include <asm/airq.h>
#include <asm/tpi.h>
#include "kvm-s390.h"
#include "gaccess.h"
#include "trace-s390.h"
#include "pci.h"
#include "gmap.h"

#define PFAULT_INIT 0x0600
#define PFAULT_DONE 0x0680
#define VIRTIO_PARAM 0x0d00

static struct kvm_s390_gib *gib;

/* handle external calls via sigp interpretation facility */
static int sca_ext_call_pending(struct kvm_vcpu *vcpu, int *src_id)
{
        struct esca_block *sca = vcpu->kvm->arch.sca;
        union esca_sigp_ctrl sigp_ctrl = sca->cpu[vcpu->vcpu_id].sigp_ctrl;

        if (!kvm_s390_test_cpuflags(vcpu, CPUSTAT_ECALL_PEND))
                return 0;

        BUG_ON(!kvm_s390_use_sca_entries());

        if (src_id)
                *src_id = sigp_ctrl.scn;

        return sigp_ctrl.c;
}

static int sca_inject_ext_call(struct kvm_vcpu *vcpu, int src_id)
{
        struct esca_block *sca = vcpu->kvm->arch.sca;
        union esca_sigp_ctrl *sigp_ctrl = &sca->cpu[vcpu->vcpu_id].sigp_ctrl;
        union esca_sigp_ctrl old_val, new_val = {.scn = src_id, .c = 1};
        int expect, rc;

        BUG_ON(!kvm_s390_use_sca_entries());

        old_val = READ_ONCE(*sigp_ctrl);
        old_val.c = 0;

        expect = old_val.value;
        rc = cmpxchg(&sigp_ctrl->value, old_val.value, new_val.value);

        if (rc != expect) {
                /* another external call is pending */
                return -EBUSY;
        }
        kvm_s390_set_cpuflags(vcpu, CPUSTAT_ECALL_PEND);
        return 0;
}

static void sca_clear_ext_call(struct kvm_vcpu *vcpu)
{
        struct esca_block *sca = vcpu->kvm->arch.sca;
        union esca_sigp_ctrl *sigp_ctrl = &sca->cpu[vcpu->vcpu_id].sigp_ctrl;

        if (!kvm_s390_use_sca_entries())
                return;
        kvm_s390_clear_cpuflags(vcpu, CPUSTAT_ECALL_PEND);

        WRITE_ONCE(sigp_ctrl->value, 0);
}

int psw_extint_disabled(struct kvm_vcpu *vcpu)
{
        return !(vcpu->arch.sie_block->gpsw.mask & PSW_MASK_EXT);
}

static int psw_ioint_disabled(struct kvm_vcpu *vcpu)
{
        return !(vcpu->arch.sie_block->gpsw.mask & PSW_MASK_IO);
}

static int psw_mchk_disabled(struct kvm_vcpu *vcpu)
{
        return !(vcpu->arch.sie_block->gpsw.mask & PSW_MASK_MCHECK);
}

static int psw_interrupts_disabled(struct kvm_vcpu *vcpu)
{
        return psw_extint_disabled(vcpu) &&
               psw_ioint_disabled(vcpu) &&
               psw_mchk_disabled(vcpu);
}

static int ckc_interrupts_enabled(struct kvm_vcpu *vcpu)
{
        if (psw_extint_disabled(vcpu) ||
            !(vcpu->arch.sie_block->gcr[0] & CR0_CLOCK_COMPARATOR_SUBMASK))
                return 0;
        if (guestdbg_enabled(vcpu) && guestdbg_sstep_enabled(vcpu))
                /* No timer interrupts when single stepping */
                return 0;
        return 1;
}

static int ckc_irq_pending(struct kvm_vcpu *vcpu)
{
        const u64 now = kvm_s390_get_tod_clock_fast(vcpu->kvm);
        const u64 ckc = vcpu->arch.sie_block->ckc;

        if (vcpu->arch.sie_block->gcr[0] & CR0_CLOCK_COMPARATOR_SIGN) {
                if ((s64)ckc >= (s64)now)
                        return 0;
        } else if (ckc >= now) {
                return 0;
        }
        return ckc_interrupts_enabled(vcpu);
}

static int cpu_timer_interrupts_enabled(struct kvm_vcpu *vcpu)
{
        return !psw_extint_disabled(vcpu) &&
               (vcpu->arch.sie_block->gcr[0] & CR0_CPU_TIMER_SUBMASK);
}

static int cpu_timer_irq_pending(struct kvm_vcpu *vcpu)
{
        if (!cpu_timer_interrupts_enabled(vcpu))
                return 0;
        return kvm_s390_get_cpu_timer(vcpu) >> 63;
}

static uint64_t isc_to_isc_bits(int isc)
{
        return (0x80 >> isc) << 24;
}

static inline u32 isc_to_int_word(u8 isc)
{
        return ((u32)isc << 27) | 0x80000000;
}

static inline u8 int_word_to_isc(u32 int_word)
{
        return (int_word & 0x38000000) >> 27;
}

/*
 * To use atomic bitmap functions, we have to provide a bitmap address
 * that is u64 aligned. However, the ipm might be u32 aligned.
 * Therefore, we logically start the bitmap at the very beginning of the
 * struct and fixup the bit number.
 */
#define IPM_BIT_OFFSET (offsetof(struct kvm_s390_gisa, ipm) * BITS_PER_BYTE)

/**
 * gisa_set_iam - change the GISA interruption alert mask
 *
 * @gisa: gisa to operate on
 * @iam: new IAM value to use
 *
 * Change the IAM atomically with the next alert address and the IPM
 * of the GISA if the GISA is not part of the GIB alert list. All three
 * fields are located in the first long word of the GISA.
 *
 * Returns: 0 on success
 *          -EBUSY in case the gisa is part of the alert list
 */
static inline int gisa_set_iam(struct kvm_s390_gisa *gisa, u8 iam)
{
        u64 word, _word;

        word = READ_ONCE(gisa->u64.word[0]);
        do {
                if ((u64)gisa != word >> 32)
                        return -EBUSY;
                _word = (word & ~0xffUL) | iam;
        } while (!try_cmpxchg(&gisa->u64.word[0], &word, _word));

        return 0;
}

/**
 * gisa_clear_ipm - clear the GISA interruption pending mask
 *
 * @gisa: gisa to operate on
 *
 * Clear the IPM atomically with the next alert address and the IAM
 * of the GISA unconditionally. All three fields are located in the
 * first long word of the GISA.
 */
static inline void gisa_clear_ipm(struct kvm_s390_gisa *gisa)
{
        u64 word, _word;

        word = READ_ONCE(gisa->u64.word[0]);
        do {
                _word = word & ~(0xffUL << 24);
        } while (!try_cmpxchg(&gisa->u64.word[0], &word, _word));
}

/**
 * gisa_get_ipm_or_restore_iam - return IPM or restore GISA IAM
 *
 * @gi: gisa interrupt struct to work on
 *
 * Atomically restores the interruption alert mask if none of the
 * relevant ISCs are pending and return the IPM.
 *
 * Returns: the relevant pending ISCs
 */
static inline u8 gisa_get_ipm_or_restore_iam(struct kvm_s390_gisa_interrupt *gi)
{
        u8 pending_mask, alert_mask;
        u64 word, _word;

        word = READ_ONCE(gi->origin->u64.word[0]);
        do {
                alert_mask = READ_ONCE(gi->alert.mask);
                pending_mask = (u8)(word >> 24) & alert_mask;
                if (pending_mask)
                        return pending_mask;
                _word = (word & ~0xffUL) | alert_mask;
        } while (!try_cmpxchg(&gi->origin->u64.word[0], &word, _word));

        return 0;
}

static inline void gisa_set_ipm_gisc(struct kvm_s390_gisa *gisa, u32 gisc)
{
        set_bit_inv(IPM_BIT_OFFSET + gisc, (unsigned long *) gisa);
}

static inline u8 gisa_get_ipm(struct kvm_s390_gisa *gisa)
{
        return READ_ONCE(gisa->ipm);
}

static inline int gisa_tac_ipm_gisc(struct kvm_s390_gisa *gisa, u32 gisc)
{
        return test_and_clear_bit_inv(IPM_BIT_OFFSET + gisc, (unsigned long *) gisa);
}

static inline unsigned long pending_irqs_no_gisa(struct kvm_vcpu *vcpu)
{
        unsigned long pending = vcpu->kvm->arch.float_int.pending_irqs |
                                vcpu->arch.local_int.pending_irqs;

        pending &= ~vcpu->kvm->arch.float_int.masked_irqs;
        return pending;
}

static inline unsigned long pending_irqs(struct kvm_vcpu *vcpu)
{
        struct kvm_s390_gisa_interrupt *gi = &vcpu->kvm->arch.gisa_int;
        unsigned long pending_mask;

        pending_mask = pending_irqs_no_gisa(vcpu);
        if (gi->origin)
                pending_mask |= gisa_get_ipm(gi->origin) << IRQ_PEND_IO_ISC_7;
        return pending_mask;
}

static inline int isc_to_irq_type(unsigned long isc)
{
        return IRQ_PEND_IO_ISC_0 - isc;
}

static inline int irq_type_to_isc(unsigned long irq_type)
{
        return IRQ_PEND_IO_ISC_0 - irq_type;
}

static unsigned long disable_iscs(struct kvm_vcpu *vcpu,
                                   unsigned long active_mask)
{
        int i;

        for (i = 0; i <= MAX_ISC; i++)
                if (!(vcpu->arch.sie_block->gcr[6] & isc_to_isc_bits(i)))
                        active_mask &= ~(1UL << (isc_to_irq_type(i)));

        return active_mask;
}

static unsigned long deliverable_irqs(struct kvm_vcpu *vcpu)
{
        unsigned long active_mask;

        active_mask = pending_irqs(vcpu);
        if (!active_mask)
                return 0;

        if (psw_extint_disabled(vcpu))
                active_mask &= ~IRQ_PEND_EXT_MASK;
        if (psw_ioint_disabled(vcpu))
                active_mask &= ~IRQ_PEND_IO_MASK;
        else
                active_mask = disable_iscs(vcpu, active_mask);
        if (!(vcpu->arch.sie_block->gcr[0] & CR0_EXTERNAL_CALL_SUBMASK))
                __clear_bit(IRQ_PEND_EXT_EXTERNAL, &active_mask);
        if (!(vcpu->arch.sie_block->gcr[0] & CR0_EMERGENCY_SIGNAL_SUBMASK))
                __clear_bit(IRQ_PEND_EXT_EMERGENCY, &active_mask);
        if (!(vcpu->arch.sie_block->gcr[0] & CR0_CLOCK_COMPARATOR_SUBMASK))
                __clear_bit(IRQ_PEND_EXT_CLOCK_COMP, &active_mask);
        if (!(vcpu->arch.sie_block->gcr[0] & CR0_CPU_TIMER_SUBMASK))
                __clear_bit(IRQ_PEND_EXT_CPU_TIMER, &active_mask);
        if (!(vcpu->arch.sie_block->gcr[0] & CR0_SERVICE_SIGNAL_SUBMASK)) {
                __clear_bit(IRQ_PEND_EXT_SERVICE, &active_mask);
                __clear_bit(IRQ_PEND_EXT_SERVICE_EV, &active_mask);
        }
        if (psw_mchk_disabled(vcpu))
                active_mask &= ~IRQ_PEND_MCHK_MASK;
        /* PV guest cpus can have a single interruption injected at a time. */
        if (kvm_s390_pv_cpu_get_handle(vcpu) &&
            vcpu->arch.sie_block->iictl != IICTL_CODE_NONE)
                active_mask &= ~(IRQ_PEND_EXT_II_MASK |
                                 IRQ_PEND_IO_MASK |
                                 IRQ_PEND_MCHK_MASK);
        /*
         * Check both floating and local interrupt's cr14 because
         * bit IRQ_PEND_MCHK_REP could be set in both cases.
         */
        if (!(vcpu->arch.sie_block->gcr[14] &
           (vcpu->kvm->arch.float_int.mchk.cr14 |
           vcpu->arch.local_int.irq.mchk.cr14)))
                __clear_bit(IRQ_PEND_MCHK_REP, &active_mask);

        /*
         * STOP irqs will never be actively delivered. They are triggered via
         * intercept requests and cleared when the stop intercept is performed.
         */
        __clear_bit(IRQ_PEND_SIGP_STOP, &active_mask);

        return active_mask;
}

static void __set_cpu_idle(struct kvm_vcpu *vcpu)
{
        kvm_s390_set_cpuflags(vcpu, CPUSTAT_WAIT);
        set_bit(vcpu->vcpu_idx, vcpu->kvm->arch.idle_mask);
}

static void __unset_cpu_idle(struct kvm_vcpu *vcpu)
{
        kvm_s390_clear_cpuflags(vcpu, CPUSTAT_WAIT);
        clear_bit(vcpu->vcpu_idx, vcpu->kvm->arch.idle_mask);
}

static void __reset_intercept_indicators(struct kvm_vcpu *vcpu)
{
        kvm_s390_clear_cpuflags(vcpu, CPUSTAT_IO_INT | CPUSTAT_EXT_INT |
                                      CPUSTAT_STOP_INT);
        vcpu->arch.sie_block->lctl = 0x0000;
        vcpu->arch.sie_block->ictl &= ~(ICTL_LPSW | ICTL_STCTL | ICTL_PINT);

        if (guestdbg_enabled(vcpu)) {
                vcpu->arch.sie_block->lctl |= (LCTL_CR0 | LCTL_CR9 |
                                               LCTL_CR10 | LCTL_CR11);
                vcpu->arch.sie_block->ictl |= (ICTL_STCTL | ICTL_PINT);
        }
}

static void set_intercept_indicators_io(struct kvm_vcpu *vcpu)
{
        if (!(pending_irqs_no_gisa(vcpu) & IRQ_PEND_IO_MASK))
                return;
        if (psw_ioint_disabled(vcpu))
                kvm_s390_set_cpuflags(vcpu, CPUSTAT_IO_INT);
        else
                vcpu->arch.sie_block->lctl |= LCTL_CR6;
}

static void set_intercept_indicators_ext(struct kvm_vcpu *vcpu)
{
        if (!(pending_irqs_no_gisa(vcpu) & IRQ_PEND_EXT_MASK))
                return;
        if (psw_extint_disabled(vcpu))
                kvm_s390_set_cpuflags(vcpu, CPUSTAT_EXT_INT);
        else
                vcpu->arch.sie_block->lctl |= LCTL_CR0;
}

static void set_intercept_indicators_mchk(struct kvm_vcpu *vcpu)
{
        if (!(pending_irqs_no_gisa(vcpu) & IRQ_PEND_MCHK_MASK))
                return;
        if (psw_mchk_disabled(vcpu))
                vcpu->arch.sie_block->ictl |= ICTL_LPSW;
        else
                vcpu->arch.sie_block->lctl |= LCTL_CR14;
}

static void set_intercept_indicators_stop(struct kvm_vcpu *vcpu)
{
        if (kvm_s390_is_stop_irq_pending(vcpu))
                kvm_s390_set_cpuflags(vcpu, CPUSTAT_STOP_INT);
}

/* Set interception request for non-deliverable interrupts */
static void set_intercept_indicators(struct kvm_vcpu *vcpu)
{
        set_intercept_indicators_io(vcpu);
        set_intercept_indicators_ext(vcpu);
        set_intercept_indicators_mchk(vcpu);
        set_intercept_indicators_stop(vcpu);
}

static int __must_check __deliver_cpu_timer(struct kvm_vcpu *vcpu)
{
        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
        int rc = 0;

        vcpu->stat.deliver_cputm++;
        trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, KVM_S390_INT_CPU_TIMER,
                                         0, 0);
        if (kvm_s390_pv_cpu_is_protected(vcpu)) {
                vcpu->arch.sie_block->iictl = IICTL_CODE_EXT;
                vcpu->arch.sie_block->eic = EXT_IRQ_CPU_TIMER;
        } else {
                rc  = put_guest_lc(vcpu, EXT_IRQ_CPU_TIMER,
                                   (u16 *)__LC_EXT_INT_CODE);
                rc |= put_guest_lc(vcpu, 0, (u16 *)__LC_EXT_CPU_ADDR);
                rc |= write_guest_lc(vcpu, __LC_EXT_OLD_PSW,
                                     &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
                rc |= read_guest_lc(vcpu, __LC_EXT_NEW_PSW,
                                    &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
        }
        clear_bit(IRQ_PEND_EXT_CPU_TIMER, &li->pending_irqs);
        return rc ? -EFAULT : 0;
}

static int __must_check __deliver_ckc(struct kvm_vcpu *vcpu)
{
        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
        int rc = 0;

        vcpu->stat.deliver_ckc++;
        trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, KVM_S390_INT_CLOCK_COMP,
                                         0, 0);
        if (kvm_s390_pv_cpu_is_protected(vcpu)) {
                vcpu->arch.sie_block->iictl = IICTL_CODE_EXT;
                vcpu->arch.sie_block->eic = EXT_IRQ_CLK_COMP;
        } else {
                rc  = put_guest_lc(vcpu, EXT_IRQ_CLK_COMP,
                                   (u16 __user *)__LC_EXT_INT_CODE);
                rc |= put_guest_lc(vcpu, 0, (u16 *)__LC_EXT_CPU_ADDR);
                rc |= write_guest_lc(vcpu, __LC_EXT_OLD_PSW,
                                     &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
                rc |= read_guest_lc(vcpu, __LC_EXT_NEW_PSW,
                                    &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
        }
        clear_bit(IRQ_PEND_EXT_CLOCK_COMP, &li->pending_irqs);
        return rc ? -EFAULT : 0;
}

static int __must_check __deliver_pfault_init(struct kvm_vcpu *vcpu)
{
        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
        struct kvm_s390_ext_info ext;
        int rc;

        spin_lock(&li->lock);
        ext = li->irq.ext;
        clear_bit(IRQ_PEND_PFAULT_INIT, &li->pending_irqs);
        li->irq.ext.ext_params2 = 0;
        spin_unlock(&li->lock);

        VCPU_EVENT(vcpu, 4, "deliver: pfault init token 0x%llx",
                   ext.ext_params2);
        trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id,
                                         KVM_S390_INT_PFAULT_INIT,
                                         0, ext.ext_params2);

        rc  = put_guest_lc(vcpu, EXT_IRQ_CP_SERVICE, (u16 *) __LC_EXT_INT_CODE);
        rc |= put_guest_lc(vcpu, PFAULT_INIT, (u16 *) __LC_EXT_CPU_ADDR);
        rc |= write_guest_lc(vcpu, __LC_EXT_OLD_PSW,
                             &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
        rc |= read_guest_lc(vcpu, __LC_EXT_NEW_PSW,
                            &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
        rc |= put_guest_lc(vcpu, ext.ext_params2, (u64 *) __LC_EXT_PARAMS2);
        return rc ? -EFAULT : 0;
}

static int __write_machine_check(struct kvm_vcpu *vcpu,
                                 struct kvm_s390_mchk_info *mchk)
{
        unsigned long ext_sa_addr;
        unsigned long lc;
        freg_t fprs[NUM_FPRS];
        union mci mci;
        int rc;

        /*
         * All other possible payload for a machine check (e.g. the register
         * contents in the save area) will be handled by the ultravisor, as
         * the hypervisor does not not have the needed information for
         * protected guests.
         */
        if (kvm_s390_pv_cpu_is_protected(vcpu)) {
                vcpu->arch.sie_block->iictl = IICTL_CODE_MCHK;
                vcpu->arch.sie_block->mcic = mchk->mcic;
                vcpu->arch.sie_block->faddr = mchk->failing_storage_address;
                vcpu->arch.sie_block->edc = mchk->ext_damage_code;
                return 0;
        }

        mci.val = mchk->mcic;
        /* take care of lazy register loading */
        kvm_s390_fpu_store(vcpu->run);
        save_access_regs(vcpu->run->s.regs.acrs);
        if (cpu_has_gs() && vcpu->arch.gs_enabled)
                save_gs_cb(current->thread.gs_cb);

        /* Extended save area */
        rc = read_guest_lc(vcpu, __LC_MCESAD, &ext_sa_addr,
                           sizeof(unsigned long));
        /* Only bits 0 through 63-LC are used for address formation */
        lc = ext_sa_addr & MCESA_LC_MASK;
        if (test_kvm_facility(vcpu->kvm, 133)) {
                switch (lc) {
                case 0:
                case 10:
                        ext_sa_addr &= ~0x3ffUL;
                        break;
                case 11:
                        ext_sa_addr &= ~0x7ffUL;
                        break;
                case 12:
                        ext_sa_addr &= ~0xfffUL;
                        break;
                default:
                        ext_sa_addr = 0;
                        break;
                }
        } else {
                ext_sa_addr &= ~0x3ffUL;
        }

        if (!rc && mci.vr && ext_sa_addr && test_kvm_facility(vcpu->kvm, 129)) {
                if (write_guest_abs(vcpu, ext_sa_addr, vcpu->run->s.regs.vrs,
                                    512))
                        mci.vr = 0;
        } else {
                mci.vr = 0;
        }
        if (!rc && mci.gs && ext_sa_addr && test_kvm_facility(vcpu->kvm, 133)
            && (lc == 11 || lc == 12)) {
                if (write_guest_abs(vcpu, ext_sa_addr + 1024,
                                    &vcpu->run->s.regs.gscb, 32))
                        mci.gs = 0;
        } else {
                mci.gs = 0;
        }

        /* General interruption information */
        rc |= put_guest_lc(vcpu, 1, (u8 __user *) __LC_AR_MODE_ID);
        rc |= write_guest_lc(vcpu, __LC_MCK_OLD_PSW,
                             &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
        rc |= read_guest_lc(vcpu, __LC_MCK_NEW_PSW,
                            &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
        rc |= put_guest_lc(vcpu, mci.val, (u64 __user *) __LC_MCCK_CODE);

        /* Register-save areas */
        if (cpu_has_vx()) {
                convert_vx_to_fp(fprs, (__vector128 *) vcpu->run->s.regs.vrs);
                rc |= write_guest_lc(vcpu, __LC_FPREGS_SAVE_AREA, fprs, 128);
        } else {
                rc |= write_guest_lc(vcpu, __LC_FPREGS_SAVE_AREA,
                                     vcpu->run->s.regs.fprs, 128);
        }
        rc |= write_guest_lc(vcpu, __LC_GPREGS_SAVE_AREA,
                             vcpu->run->s.regs.gprs, 128);
        rc |= put_guest_lc(vcpu, vcpu->run->s.regs.fpc,
                           (u32 __user *) __LC_FP_CREG_SAVE_AREA);
        rc |= put_guest_lc(vcpu, vcpu->arch.sie_block->todpr,
                           (u32 __user *) __LC_TOD_PROGREG_SAVE_AREA);
        rc |= put_guest_lc(vcpu, kvm_s390_get_cpu_timer(vcpu),
                           (u64 __user *) __LC_CPU_TIMER_SAVE_AREA);
        rc |= put_guest_lc(vcpu, vcpu->arch.sie_block->ckc >> 8,
                           (u64 __user *) __LC_CLOCK_COMP_SAVE_AREA);
        rc |= write_guest_lc(vcpu, __LC_AREGS_SAVE_AREA,
                             &vcpu->run->s.regs.acrs, 64);
        rc |= write_guest_lc(vcpu, __LC_CREGS_SAVE_AREA,
                             &vcpu->arch.sie_block->gcr, 128);

        /* Extended interruption information */
        rc |= put_guest_lc(vcpu, mchk->ext_damage_code,
                           (u32 __user *) __LC_EXT_DAMAGE_CODE);
        rc |= put_guest_lc(vcpu, mchk->failing_storage_address,
                           (u64 __user *) __LC_MCCK_FAIL_STOR_ADDR);
        rc |= write_guest_lc(vcpu, __LC_PSW_SAVE_AREA, &mchk->fixed_logout,
                             sizeof(mchk->fixed_logout));
        return rc ? -EFAULT : 0;
}

static int __must_check __deliver_machine_check(struct kvm_vcpu *vcpu)
{
        struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
        struct kvm_s390_mchk_info mchk = {};
        int deliver = 0;
        int rc = 0;

        spin_lock(&fi->lock);
        spin_lock(&li->lock);
        if (test_bit(IRQ_PEND_MCHK_EX, &li->pending_irqs) ||
            test_bit(IRQ_PEND_MCHK_REP, &li->pending_irqs)) {
                /*
                 * If there was an exigent machine check pending, then any
                 * repressible machine checks that might have been pending
                 * are indicated along with it, so always clear bits for
                 * repressible and exigent interrupts
                 */
                mchk = li->irq.mchk;
                clear_bit(IRQ_PEND_MCHK_EX, &li->pending_irqs);
                clear_bit(IRQ_PEND_MCHK_REP, &li->pending_irqs);
                memset(&li->irq.mchk, 0, sizeof(mchk));
                deliver = 1;
        }
        /*
         * We indicate floating repressible conditions along with
         * other pending conditions. Channel Report Pending and Channel
         * Subsystem damage are the only two and are indicated by
         * bits in mcic and masked in cr14.
         */
        if (test_and_clear_bit(IRQ_PEND_MCHK_REP, &fi->pending_irqs)) {
                mchk.mcic |= fi->mchk.mcic;
                mchk.cr14 |= fi->mchk.cr14;
                memset(&fi->mchk, 0, sizeof(mchk));
                deliver = 1;
        }
        spin_unlock(&li->lock);
        spin_unlock(&fi->lock);

        if (deliver) {
                VCPU_EVENT(vcpu, 3, "deliver: machine check mcic 0x%llx",
                           mchk.mcic);
                trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id,
                                                 KVM_S390_MCHK,
                                                 mchk.cr14, mchk.mcic);
                vcpu->stat.deliver_machine_check++;
                rc = __write_machine_check(vcpu, &mchk);
        }
        return rc;
}

static int __must_check __deliver_restart(struct kvm_vcpu *vcpu)
{
        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
        int rc = 0;

        VCPU_EVENT(vcpu, 3, "%s", "deliver: cpu restart");
        vcpu->stat.deliver_restart_signal++;
        trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, KVM_S390_RESTART, 0, 0);

        if (kvm_s390_pv_cpu_is_protected(vcpu)) {
                vcpu->arch.sie_block->iictl = IICTL_CODE_RESTART;
        } else {
                rc  = write_guest_lc(vcpu,
                                     offsetof(struct lowcore, restart_old_psw),
                                     &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
                rc |= read_guest_lc(vcpu, offsetof(struct lowcore, restart_psw),
                                    &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
        }
        clear_bit(IRQ_PEND_RESTART, &li->pending_irqs);
        return rc ? -EFAULT : 0;
}

static int __must_check __deliver_set_prefix(struct kvm_vcpu *vcpu)
{
        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
        struct kvm_s390_prefix_info prefix;

        spin_lock(&li->lock);
        prefix = li->irq.prefix;
        li->irq.prefix.address = 0;
        clear_bit(IRQ_PEND_SET_PREFIX, &li->pending_irqs);
        spin_unlock(&li->lock);

        vcpu->stat.deliver_prefix_signal++;
        trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id,
                                         KVM_S390_SIGP_SET_PREFIX,
                                         prefix.address, 0);

        kvm_s390_set_prefix(vcpu, prefix.address);
        return 0;
}

static int __must_check __deliver_emergency_signal(struct kvm_vcpu *vcpu)
{
        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
        int rc;
        int cpu_addr;

        spin_lock(&li->lock);
        cpu_addr = find_first_bit(li->sigp_emerg_pending, KVM_MAX_VCPUS);
        clear_bit(cpu_addr, li->sigp_emerg_pending);
        if (bitmap_empty(li->sigp_emerg_pending, KVM_MAX_VCPUS))
                clear_bit(IRQ_PEND_EXT_EMERGENCY, &li->pending_irqs);
        spin_unlock(&li->lock);

        VCPU_EVENT(vcpu, 4, "%s", "deliver: sigp emerg");
        vcpu->stat.deliver_emergency_signal++;
        trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, KVM_S390_INT_EMERGENCY,
                                         cpu_addr, 0);
        if (kvm_s390_pv_cpu_is_protected(vcpu)) {
                vcpu->arch.sie_block->iictl = IICTL_CODE_EXT;
                vcpu->arch.sie_block->eic = EXT_IRQ_EMERGENCY_SIG;
                vcpu->arch.sie_block->extcpuaddr = cpu_addr;
                return 0;
        }

        rc  = put_guest_lc(vcpu, EXT_IRQ_EMERGENCY_SIG,
                           (u16 *)__LC_EXT_INT_CODE);
        rc |= put_guest_lc(vcpu, cpu_addr, (u16 *)__LC_EXT_CPU_ADDR);
        rc |= write_guest_lc(vcpu, __LC_EXT_OLD_PSW,
                             &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
        rc |= read_guest_lc(vcpu, __LC_EXT_NEW_PSW,
                            &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
        return rc ? -EFAULT : 0;
}

static int __must_check __deliver_external_call(struct kvm_vcpu *vcpu)
{
        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
        struct kvm_s390_extcall_info extcall;
        int rc;

        spin_lock(&li->lock);
        extcall = li->irq.extcall;
        li->irq.extcall.code = 0;
        clear_bit(IRQ_PEND_EXT_EXTERNAL, &li->pending_irqs);
        spin_unlock(&li->lock);

        VCPU_EVENT(vcpu, 4, "%s", "deliver: sigp ext call");
        vcpu->stat.deliver_external_call++;
        trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id,
                                         KVM_S390_INT_EXTERNAL_CALL,
                                         extcall.code, 0);
        if (kvm_s390_pv_cpu_is_protected(vcpu)) {
                vcpu->arch.sie_block->iictl = IICTL_CODE_EXT;
                vcpu->arch.sie_block->eic = EXT_IRQ_EXTERNAL_CALL;
                vcpu->arch.sie_block->extcpuaddr = extcall.code;
                return 0;
        }

        rc  = put_guest_lc(vcpu, EXT_IRQ_EXTERNAL_CALL,
                           (u16 *)__LC_EXT_INT_CODE);
        rc |= put_guest_lc(vcpu, extcall.code, (u16 *)__LC_EXT_CPU_ADDR);
        rc |= write_guest_lc(vcpu, __LC_EXT_OLD_PSW,
                             &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
        rc |= read_guest_lc(vcpu, __LC_EXT_NEW_PSW, &vcpu->arch.sie_block->gpsw,
                            sizeof(psw_t));
        return rc ? -EFAULT : 0;
}

static int __deliver_prog_pv(struct kvm_vcpu *vcpu, u16 code)
{
        switch (code) {
        case PGM_SPECIFICATION:
                vcpu->arch.sie_block->iictl = IICTL_CODE_SPECIFICATION;
                break;
        case PGM_OPERAND:
                vcpu->arch.sie_block->iictl = IICTL_CODE_OPERAND;
                break;
        default:
                return -EINVAL;
        }
        return 0;
}

static int __must_check __deliver_prog(struct kvm_vcpu *vcpu)
{
        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
        struct kvm_s390_pgm_info pgm_info;
        int rc = 0, nullifying = false;
        u16 ilen;

        spin_lock(&li->lock);
        pgm_info = li->irq.pgm;
        clear_bit(IRQ_PEND_PROG, &li->pending_irqs);
        memset(&li->irq.pgm, 0, sizeof(pgm_info));
        spin_unlock(&li->lock);

        ilen = pgm_info.flags & KVM_S390_PGM_FLAGS_ILC_MASK;
        VCPU_EVENT(vcpu, 3, "deliver: program irq code 0x%x, ilen:%d",
                   pgm_info.code, ilen);
        vcpu->stat.deliver_program++;
        trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, KVM_S390_PROGRAM_INT,
                                         pgm_info.code, 0);

        /* PER is handled by the ultravisor */
        if (kvm_s390_pv_cpu_is_protected(vcpu))
                return __deliver_prog_pv(vcpu, pgm_info.code & ~PGM_PER);

        switch (pgm_info.code & ~PGM_PER) {
        case PGM_AFX_TRANSLATION:
        case PGM_ASX_TRANSLATION:
        case PGM_EX_TRANSLATION:
        case PGM_LFX_TRANSLATION:
        case PGM_LSTE_SEQUENCE:
        case PGM_LSX_TRANSLATION:
        case PGM_LX_TRANSLATION:
        case PGM_PRIMARY_AUTHORITY:
        case PGM_SECONDARY_AUTHORITY:
                nullifying = true;
                fallthrough;
        case PGM_SPACE_SWITCH:
                rc = put_guest_lc(vcpu, pgm_info.trans_exc_code,
                                  (u64 *)__LC_TRANS_EXC_CODE);
                break;
        case PGM_ALEN_TRANSLATION:
        case PGM_ALE_SEQUENCE:
        case PGM_ASTE_INSTANCE:
        case PGM_ASTE_SEQUENCE:
        case PGM_ASTE_VALIDITY:
        case PGM_EXTENDED_AUTHORITY:
                rc = put_guest_lc(vcpu, pgm_info.exc_access_id,
                                  (u8 *)__LC_EXC_ACCESS_ID);
                nullifying = true;
                break;
        case PGM_ASCE_TYPE:
        case PGM_PAGE_TRANSLATION:
        case PGM_REGION_FIRST_TRANS:
        case PGM_REGION_SECOND_TRANS:
        case PGM_REGION_THIRD_TRANS:
        case PGM_SEGMENT_TRANSLATION:
                rc = put_guest_lc(vcpu, pgm_info.trans_exc_code,
                                  (u64 *)__LC_TRANS_EXC_CODE);
                rc |= put_guest_lc(vcpu, pgm_info.exc_access_id,
                                   (u8 *)__LC_EXC_ACCESS_ID);
                rc |= put_guest_lc(vcpu, pgm_info.op_access_id,
                                   (u8 *)__LC_OP_ACCESS_ID);
                nullifying = true;
                break;
        case PGM_MONITOR:
                rc = put_guest_lc(vcpu, pgm_info.mon_class_nr,
                                  (u16 *)__LC_MON_CLASS_NR);
                rc |= put_guest_lc(vcpu, pgm_info.mon_code,
                                   (u64 *)__LC_MON_CODE);
                break;
        case PGM_VECTOR_PROCESSING:
        case PGM_DATA:
                rc = put_guest_lc(vcpu, pgm_info.data_exc_code,
                                  (u32 *)__LC_DATA_EXC_CODE);
                break;
        case PGM_PROTECTION:
                rc = put_guest_lc(vcpu, pgm_info.trans_exc_code,
                                  (u64 *)__LC_TRANS_EXC_CODE);
                rc |= put_guest_lc(vcpu, pgm_info.exc_access_id,
                                   (u8 *)__LC_EXC_ACCESS_ID);
                break;
        case PGM_STACK_FULL:
        case PGM_STACK_EMPTY:
        case PGM_STACK_SPECIFICATION:
        case PGM_STACK_TYPE:
        case PGM_STACK_OPERATION:
        case PGM_TRACE_TABEL:
        case PGM_CRYPTO_OPERATION:
                nullifying = true;
                break;
        }

        if (pgm_info.code & PGM_PER) {
                rc |= put_guest_lc(vcpu, pgm_info.per_code,
                                   (u8 *) __LC_PER_CODE);
                rc |= put_guest_lc(vcpu, pgm_info.per_atmid,
                                   (u8 *)__LC_PER_ATMID);
                rc |= put_guest_lc(vcpu, pgm_info.per_address,
                                   (u64 *) __LC_PER_ADDRESS);
                rc |= put_guest_lc(vcpu, pgm_info.per_access_id,
                                   (u8 *) __LC_PER_ACCESS_ID);
        }

        if (nullifying && !(pgm_info.flags & KVM_S390_PGM_FLAGS_NO_REWIND))
                kvm_s390_rewind_psw(vcpu, ilen);

        /* bit 1+2 of the target are the ilc, so we can directly use ilen */
        rc |= put_guest_lc(vcpu, ilen, (u16 *) __LC_PGM_ILC);
        rc |= put_guest_lc(vcpu, vcpu->arch.sie_block->gbea,
                                 (u64 *) __LC_PGM_LAST_BREAK);
        rc |= put_guest_lc(vcpu, pgm_info.code, (u16 *)__LC_PGM_CODE);
        rc |= write_guest_lc(vcpu, __LC_PGM_OLD_PSW,
                             &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
        rc |= read_guest_lc(vcpu, __LC_PGM_NEW_PSW,
                            &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
        return rc ? -EFAULT : 0;
}

#define SCCB_MASK 0xFFFFFFF8
#define SCCB_EVENT_PENDING 0x3

static int write_sclp(struct kvm_vcpu *vcpu, u32 parm)
{
        int rc;

        if (kvm_s390_pv_cpu_get_handle(vcpu)) {
                vcpu->arch.sie_block->iictl = IICTL_CODE_EXT;
                vcpu->arch.sie_block->eic = EXT_IRQ_SERVICE_SIG;
                vcpu->arch.sie_block->eiparams = parm;
                return 0;
        }

        rc  = put_guest_lc(vcpu, EXT_IRQ_SERVICE_SIG, (u16 *)__LC_EXT_INT_CODE);
        rc |= put_guest_lc(vcpu, 0, (u16 *)__LC_EXT_CPU_ADDR);
        rc |= write_guest_lc(vcpu, __LC_EXT_OLD_PSW,
                             &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
        rc |= read_guest_lc(vcpu, __LC_EXT_NEW_PSW,
                            &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
        rc |= put_guest_lc(vcpu, parm,
                           (u32 *)__LC_EXT_PARAMS);

        return rc ? -EFAULT : 0;
}

static int __must_check __deliver_service(struct kvm_vcpu *vcpu)
{
        struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
        struct kvm_s390_ext_info ext;

        spin_lock(&fi->lock);
        if (test_bit(IRQ_PEND_EXT_SERVICE, &fi->masked_irqs) ||
            !(test_bit(IRQ_PEND_EXT_SERVICE, &fi->pending_irqs))) {
                spin_unlock(&fi->lock);
                return 0;
        }
        ext = fi->srv_signal;
        memset(&fi->srv_signal, 0, sizeof(ext));
        clear_bit(IRQ_PEND_EXT_SERVICE, &fi->pending_irqs);
        clear_bit(IRQ_PEND_EXT_SERVICE_EV, &fi->pending_irqs);
        if (kvm_s390_pv_cpu_is_protected(vcpu))
                set_bit(IRQ_PEND_EXT_SERVICE, &fi->masked_irqs);
        spin_unlock(&fi->lock);

        VCPU_EVENT(vcpu, 4, "deliver: sclp parameter 0x%x",
                   ext.ext_params);
        vcpu->stat.deliver_service_signal++;
        trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, KVM_S390_INT_SERVICE,
                                         ext.ext_params, 0);

        return write_sclp(vcpu, ext.ext_params);
}

static int __must_check __deliver_service_ev(struct kvm_vcpu *vcpu)
{
        struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
        struct kvm_s390_ext_info ext;

        spin_lock(&fi->lock);
        if (!(test_bit(IRQ_PEND_EXT_SERVICE_EV, &fi->pending_irqs))) {
                spin_unlock(&fi->lock);
                return 0;
        }
        ext = fi->srv_signal;
        /* only clear the event bits */
        fi->srv_signal.ext_params &= ~SCCB_EVENT_PENDING;
        clear_bit(IRQ_PEND_EXT_SERVICE_EV, &fi->pending_irqs);
        spin_unlock(&fi->lock);

        VCPU_EVENT(vcpu, 4, "%s", "deliver: sclp parameter event");
        vcpu->stat.deliver_service_signal++;
        trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, KVM_S390_INT_SERVICE,
                                         ext.ext_params, 0);

        return write_sclp(vcpu, ext.ext_params & SCCB_EVENT_PENDING);
}

static int __must_check __deliver_pfault_done(struct kvm_vcpu *vcpu)
{
        struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
        struct kvm_s390_interrupt_info *inti;
        int rc = 0;

        spin_lock(&fi->lock);
        inti = list_first_entry_or_null(&fi->lists[FIRQ_LIST_PFAULT],
                                        struct kvm_s390_interrupt_info,
                                        list);
        if (inti) {
                list_del(&inti->list);
                fi->counters[FIRQ_CNTR_PFAULT] -= 1;
        }
        if (list_empty(&fi->lists[FIRQ_LIST_PFAULT]))
                clear_bit(IRQ_PEND_PFAULT_DONE, &fi->pending_irqs);
        spin_unlock(&fi->lock);

        if (inti) {
                trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id,
                                                 KVM_S390_INT_PFAULT_DONE, 0,
                                                 inti->ext.ext_params2);
                VCPU_EVENT(vcpu, 4, "deliver: pfault done token 0x%llx",
                           inti->ext.ext_params2);

                rc  = put_guest_lc(vcpu, EXT_IRQ_CP_SERVICE,
                                (u16 *)__LC_EXT_INT_CODE);
                rc |= put_guest_lc(vcpu, PFAULT_DONE,
                                (u16 *)__LC_EXT_CPU_ADDR);
                rc |= write_guest_lc(vcpu, __LC_EXT_OLD_PSW,
                                &vcpu->arch.sie_block->gpsw,
                                sizeof(psw_t));
                rc |= read_guest_lc(vcpu, __LC_EXT_NEW_PSW,
                                &vcpu->arch.sie_block->gpsw,
                                sizeof(psw_t));
                rc |= put_guest_lc(vcpu, inti->ext.ext_params2,
                                (u64 *)__LC_EXT_PARAMS2);
                kfree(inti);
        }
        return rc ? -EFAULT : 0;
}

static int __must_check __deliver_virtio(struct kvm_vcpu *vcpu)
{
        struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
        struct kvm_s390_interrupt_info *inti;
        int rc = 0;

        spin_lock(&fi->lock);
        inti = list_first_entry_or_null(&fi->lists[FIRQ_LIST_VIRTIO],
                                        struct kvm_s390_interrupt_info,
                                        list);
        if (inti) {
                VCPU_EVENT(vcpu, 4,
                           "deliver: virtio parm: 0x%x,parm64: 0x%llx",
                           inti->ext.ext_params, inti->ext.ext_params2);
                vcpu->stat.deliver_virtio++;
                trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id,
                                inti->type,
                                inti->ext.ext_params,
                                inti->ext.ext_params2);
                list_del(&inti->list);
                fi->counters[FIRQ_CNTR_VIRTIO] -= 1;
        }
        if (list_empty(&fi->lists[FIRQ_LIST_VIRTIO]))
                clear_bit(IRQ_PEND_VIRTIO, &fi->pending_irqs);
        spin_unlock(&fi->lock);

        if (inti) {
                rc  = put_guest_lc(vcpu, EXT_IRQ_CP_SERVICE,
                                (u16 *)__LC_EXT_INT_CODE);
                rc |= put_guest_lc(vcpu, VIRTIO_PARAM,
                                (u16 *)__LC_EXT_CPU_ADDR);
                rc |= write_guest_lc(vcpu, __LC_EXT_OLD_PSW,
                                &vcpu->arch.sie_block->gpsw,
                                sizeof(psw_t));
                rc |= read_guest_lc(vcpu, __LC_EXT_NEW_PSW,
                                &vcpu->arch.sie_block->gpsw,
                                sizeof(psw_t));
                rc |= put_guest_lc(vcpu, inti->ext.ext_params,
                                (u32 *)__LC_EXT_PARAMS);
                rc |= put_guest_lc(vcpu, inti->ext.ext_params2,
                                (u64 *)__LC_EXT_PARAMS2);
                kfree(inti);
        }
        return rc ? -EFAULT : 0;
}

static int __do_deliver_io(struct kvm_vcpu *vcpu, struct kvm_s390_io_info *io)
{
        int rc;

        if (kvm_s390_pv_cpu_is_protected(vcpu)) {
                vcpu->arch.sie_block->iictl = IICTL_CODE_IO;
                vcpu->arch.sie_block->subchannel_id = io->subchannel_id;
                vcpu->arch.sie_block->subchannel_nr = io->subchannel_nr;
                vcpu->arch.sie_block->io_int_parm = io->io_int_parm;
                vcpu->arch.sie_block->io_int_word = io->io_int_word;
                return 0;
        }

        rc  = put_guest_lc(vcpu, io->subchannel_id, (u16 *)__LC_SUBCHANNEL_ID);
        rc |= put_guest_lc(vcpu, io->subchannel_nr, (u16 *)__LC_SUBCHANNEL_NR);
        rc |= put_guest_lc(vcpu, io->io_int_parm, (u32 *)__LC_IO_INT_PARM);
        rc |= put_guest_lc(vcpu, io->io_int_word, (u32 *)__LC_IO_INT_WORD);
        rc |= write_guest_lc(vcpu, __LC_IO_OLD_PSW,
                             &vcpu->arch.sie_block->gpsw,
                             sizeof(psw_t));
        rc |= read_guest_lc(vcpu, __LC_IO_NEW_PSW,
                            &vcpu->arch.sie_block->gpsw,
                            sizeof(psw_t));
        return rc ? -EFAULT : 0;
}

static int __must_check __deliver_io(struct kvm_vcpu *vcpu,
                                     unsigned long irq_type)
{
        struct list_head *isc_list;
        struct kvm_s390_float_interrupt *fi;
        struct kvm_s390_gisa_interrupt *gi = &vcpu->kvm->arch.gisa_int;
        struct kvm_s390_interrupt_info *inti = NULL;
        struct kvm_s390_io_info io;
        u32 isc;
        int rc = 0;

        fi = &vcpu->kvm->arch.float_int;

        spin_lock(&fi->lock);
        isc = irq_type_to_isc(irq_type);
        isc_list = &fi->lists[isc];
        inti = list_first_entry_or_null(isc_list,
                                        struct kvm_s390_interrupt_info,
                                        list);
        if (inti) {
                if (inti->type & KVM_S390_INT_IO_AI_MASK)
                        VCPU_EVENT(vcpu, 4, "%s", "deliver: I/O (AI)");
                else
                        VCPU_EVENT(vcpu, 4, "deliver: I/O %x ss %x schid %04x",
                        inti->io.subchannel_id >> 8,
                        inti->io.subchannel_id >> 1 & 0x3,
                        inti->io.subchannel_nr);

                vcpu->stat.deliver_io++;
                trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id,
                                inti->type,
                                ((__u32)inti->io.subchannel_id << 16) |
                                inti->io.subchannel_nr,
                                ((__u64)inti->io.io_int_parm << 32) |
                                inti->io.io_int_word);
                list_del(&inti->list);
                fi->counters[FIRQ_CNTR_IO] -= 1;
        }
        if (list_empty(isc_list))
                clear_bit(irq_type, &fi->pending_irqs);
        spin_unlock(&fi->lock);

        if (inti) {
                rc = __do_deliver_io(vcpu, &(inti->io));
                kfree(inti);
                goto out;
        }

        if (gi->origin && gisa_tac_ipm_gisc(gi->origin, isc)) {
                /*
                 * in case an adapter interrupt was not delivered
                 * in SIE context KVM will handle the delivery
                 */
                VCPU_EVENT(vcpu, 4, "%s isc %u", "deliver: I/O (AI/gisa)", isc);
                memset(&io, 0, sizeof(io));
                io.io_int_word = isc_to_int_word(isc);
                vcpu->stat.deliver_io++;
                trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id,
                        KVM_S390_INT_IO(1, 0, 0, 0),
                        ((__u32)io.subchannel_id << 16) |
                        io.subchannel_nr,
                        ((__u64)io.io_int_parm << 32) |
                        io.io_int_word);
                rc = __do_deliver_io(vcpu, &io);
        }
out:
        return rc;
}

/* Check whether an external call is pending (deliverable or not) */
int kvm_s390_ext_call_pending(struct kvm_vcpu *vcpu)
{
        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;

        if (!kvm_s390_use_sca_entries())
                return test_bit(IRQ_PEND_EXT_EXTERNAL, &li->pending_irqs);

        return sca_ext_call_pending(vcpu, NULL);
}

int kvm_s390_vcpu_has_irq(struct kvm_vcpu *vcpu, int exclude_stop)
{
        if (deliverable_irqs(vcpu))
                return 1;

        if (kvm_cpu_has_pending_timer(vcpu))
                return 1;

        /* external call pending and deliverable */
        if (kvm_s390_ext_call_pending(vcpu) &&
            !psw_extint_disabled(vcpu) &&
            (vcpu->arch.sie_block->gcr[0] & CR0_EXTERNAL_CALL_SUBMASK))
                return 1;

        if (!exclude_stop && kvm_s390_is_stop_irq_pending(vcpu))
                return 1;
        return 0;
}

int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
{
        return ckc_irq_pending(vcpu) || cpu_timer_irq_pending(vcpu);
}

static u64 __calculate_sltime(struct kvm_vcpu *vcpu)
{
        const u64 now = kvm_s390_get_tod_clock_fast(vcpu->kvm);
        const u64 ckc = vcpu->arch.sie_block->ckc;
        u64 cputm, sltime = 0;

        if (ckc_interrupts_enabled(vcpu)) {
                if (vcpu->arch.sie_block->gcr[0] & CR0_CLOCK_COMPARATOR_SIGN) {
                        if ((s64)now < (s64)ckc)
                                sltime = tod_to_ns((s64)ckc - (s64)now);
                } else if (now < ckc) {
                        sltime = tod_to_ns(ckc - now);
                }
                /* already expired */
                if (!sltime)
                        return 0;
                if (cpu_timer_interrupts_enabled(vcpu)) {
                        cputm = kvm_s390_get_cpu_timer(vcpu);
                        /* already expired? */
                        if (cputm >> 63)
                                return 0;
                        return min_t(u64, sltime, tod_to_ns(cputm));
                }
        } else if (cpu_timer_interrupts_enabled(vcpu)) {
                sltime = kvm_s390_get_cpu_timer(vcpu);
                /* already expired? */
                if (sltime >> 63)
                        return 0;
        }
        return sltime;
}

int kvm_s390_handle_wait(struct kvm_vcpu *vcpu)
{
        struct kvm_s390_gisa_interrupt *gi = &vcpu->kvm->arch.gisa_int;
        u64 sltime;

        vcpu->stat.exit_wait_state++;

        /* fast path */
        if (kvm_arch_vcpu_runnable(vcpu))
                return 0;

        if (psw_interrupts_disabled(vcpu)) {
                VCPU_EVENT(vcpu, 3, "%s", "disabled wait");
                return -EOPNOTSUPP; /* disabled wait */
        }

        if (gi->origin &&
            (gisa_get_ipm_or_restore_iam(gi) &
             vcpu->arch.sie_block->gcr[6] >> 24))
                return 0;

        if (!ckc_interrupts_enabled(vcpu) &&
            !cpu_timer_interrupts_enabled(vcpu)) {
                VCPU_EVENT(vcpu, 3, "%s", "enabled wait w/o timer");
                __set_cpu_idle(vcpu);
                goto no_timer;
        }

        sltime = __calculate_sltime(vcpu);
        if (!sltime)
                return 0;

        __set_cpu_idle(vcpu);
        hrtimer_start(&vcpu->arch.ckc_timer, sltime, HRTIMER_MODE_REL);
        VCPU_EVENT(vcpu, 4, "enabled wait: %llu ns", sltime);
no_timer:
        kvm_vcpu_srcu_read_unlock(vcpu);
        vcpu->kvm->arch.float_int.last_sleep_cpu = vcpu->vcpu_idx;
        kvm_vcpu_halt(vcpu);
        vcpu->valid_wakeup = false;
        __unset_cpu_idle(vcpu);
        kvm_vcpu_srcu_read_lock(vcpu);

        hrtimer_cancel(&vcpu->arch.ckc_timer);
        return 0;
}

void kvm_s390_vcpu_wakeup(struct kvm_vcpu *vcpu)
{
        vcpu->valid_wakeup = true;
        kvm_vcpu_wake_up(vcpu);

        /*
         * The VCPU might not be sleeping but rather executing VSIE. Let's
         * kick it, so it leaves the SIE to process the request.
         */
        kvm_s390_vsie_kick(vcpu);
}

enum hrtimer_restart kvm_s390_idle_wakeup(struct hrtimer *timer)
{
        struct kvm_vcpu *vcpu;
        u64 sltime;

        vcpu = container_of(timer, struct kvm_vcpu, arch.ckc_timer);
        sltime = __calculate_sltime(vcpu);

        /*
         * If the monotonic clock runs faster than the tod clock we might be
         * woken up too early and have to go back to sleep to avoid deadlocks.
         */
        if (sltime && hrtimer_forward_now(timer, ns_to_ktime(sltime)))
                return HRTIMER_RESTART;
        kvm_s390_vcpu_wakeup(vcpu);
        return HRTIMER_NORESTART;
}

void kvm_s390_clear_local_irqs(struct kvm_vcpu *vcpu)
{
        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;

        spin_lock(&li->lock);
        li->pending_irqs = 0;
        bitmap_zero(li->sigp_emerg_pending, KVM_MAX_VCPUS);
        memset(&li->irq, 0, sizeof(li->irq));
        spin_unlock(&li->lock);

        sca_clear_ext_call(vcpu);
}

int __must_check kvm_s390_deliver_pending_interrupts(struct kvm_vcpu *vcpu)
{
        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
        int rc = 0;
        bool delivered = false;
        unsigned long irq_type;
        unsigned long irqs;

        __reset_intercept_indicators(vcpu);

        /* pending ckc conditions might have been invalidated */
        clear_bit(IRQ_PEND_EXT_CLOCK_COMP, &li->pending_irqs);
        if (ckc_irq_pending(vcpu))
                set_bit(IRQ_PEND_EXT_CLOCK_COMP, &li->pending_irqs);

        /* pending cpu timer conditions might have been invalidated */
        clear_bit(IRQ_PEND_EXT_CPU_TIMER, &li->pending_irqs);
        if (cpu_timer_irq_pending(vcpu))
                set_bit(IRQ_PEND_EXT_CPU_TIMER, &li->pending_irqs);

        while ((irqs = deliverable_irqs(vcpu)) && !rc) {
                /* bits are in the reverse order of interrupt priority */
                irq_type = find_last_bit(&irqs, IRQ_PEND_COUNT);
                switch (irq_type) {
                case IRQ_PEND_IO_ISC_0:
                case IRQ_PEND_IO_ISC_1:
                case IRQ_PEND_IO_ISC_2:
                case IRQ_PEND_IO_ISC_3:
                case IRQ_PEND_IO_ISC_4:
                case IRQ_PEND_IO_ISC_5:
                case IRQ_PEND_IO_ISC_6:
                case IRQ_PEND_IO_ISC_7:
                        rc = __deliver_io(vcpu, irq_type);
                        break;
                case IRQ_PEND_MCHK_EX:
                case IRQ_PEND_MCHK_REP:
                        rc = __deliver_machine_check(vcpu);
                        break;
                case IRQ_PEND_PROG:
                        rc = __deliver_prog(vcpu);
                        break;
                case IRQ_PEND_EXT_EMERGENCY:
                        rc = __deliver_emergency_signal(vcpu);
                        break;
                case IRQ_PEND_EXT_EXTERNAL:
                        rc = __deliver_external_call(vcpu);
                        break;
                case IRQ_PEND_EXT_CLOCK_COMP:
                        rc = __deliver_ckc(vcpu);
                        break;
                case IRQ_PEND_EXT_CPU_TIMER:
                        rc = __deliver_cpu_timer(vcpu);
                        break;
                case IRQ_PEND_RESTART:
                        rc = __deliver_restart(vcpu);
                        break;
                case IRQ_PEND_SET_PREFIX:
                        rc = __deliver_set_prefix(vcpu);
                        break;
                case IRQ_PEND_PFAULT_INIT:
                        rc = __deliver_pfault_init(vcpu);
                        break;
                case IRQ_PEND_EXT_SERVICE:
                        rc = __deliver_service(vcpu);
                        break;
                case IRQ_PEND_EXT_SERVICE_EV:
                        rc = __deliver_service_ev(vcpu);
                        break;
                case IRQ_PEND_PFAULT_DONE:
                        rc = __deliver_pfault_done(vcpu);
                        break;
                case IRQ_PEND_VIRTIO:
                        rc = __deliver_virtio(vcpu);
                        break;
                default:
                        WARN_ONCE(1, "Unknown pending irq type %ld", irq_type);
                        clear_bit(irq_type, &li->pending_irqs);
                }
                delivered |= !rc;
        }

        /*
         * We delivered at least one interrupt and modified the PC. Force a
         * singlestep event now.
         */
        if (delivered && guestdbg_sstep_enabled(vcpu)) {
                struct kvm_debug_exit_arch *debug_exit = &vcpu->run->debug.arch;

                debug_exit->addr = vcpu->arch.sie_block->gpsw.addr;
                debug_exit->type = KVM_SINGLESTEP;
                vcpu->guest_debug |= KVM_GUESTDBG_EXIT_PENDING;
        }

        set_intercept_indicators(vcpu);

        return rc;
}

static int __inject_prog(struct kvm_vcpu *vcpu, struct kvm_s390_irq *irq)
{
        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;

        vcpu->stat.inject_program++;
        VCPU_EVENT(vcpu, 3, "inject: program irq code 0x%x", irq->u.pgm.code);
        trace_kvm_s390_inject_vcpu(vcpu->vcpu_id, KVM_S390_PROGRAM_INT,
                                   irq->u.pgm.code, 0);

        if (!(irq->u.pgm.flags & KVM_S390_PGM_FLAGS_ILC_VALID)) {
                /* auto detection if no valid ILC was given */
                irq->u.pgm.flags &= ~KVM_S390_PGM_FLAGS_ILC_MASK;
                irq->u.pgm.flags |= kvm_s390_get_ilen(vcpu);
                irq->u.pgm.flags |= KVM_S390_PGM_FLAGS_ILC_VALID;
        }

        if (irq->u.pgm.code == PGM_PER) {
                li->irq.pgm.code |= PGM_PER;
                li->irq.pgm.flags = irq->u.pgm.flags;
                /* only modify PER related information */
                li->irq.pgm.per_address = irq->u.pgm.per_address;
                li->irq.pgm.per_code = irq->u.pgm.per_code;
                li->irq.pgm.per_atmid = irq->u.pgm.per_atmid;
                li->irq.pgm.per_access_id = irq->u.pgm.per_access_id;
        } else if (!(irq->u.pgm.code & PGM_PER)) {
                li->irq.pgm.code = (li->irq.pgm.code & PGM_PER) |
                                   irq->u.pgm.code;
                li->irq.pgm.flags = irq->u.pgm.flags;
                /* only modify non-PER information */
                li->irq.pgm.trans_exc_code = irq->u.pgm.trans_exc_code;
                li->irq.pgm.mon_code = irq->u.pgm.mon_code;
                li->irq.pgm.data_exc_code = irq->u.pgm.data_exc_code;
                li->irq.pgm.mon_class_nr = irq->u.pgm.mon_class_nr;
                li->irq.pgm.exc_access_id = irq->u.pgm.exc_access_id;
                li->irq.pgm.op_access_id = irq->u.pgm.op_access_id;
        } else {
                li->irq.pgm = irq->u.pgm;
        }
        set_bit(IRQ_PEND_PROG, &li->pending_irqs);
        return 0;
}

static int __inject_pfault_init(struct kvm_vcpu *vcpu, struct kvm_s390_irq *irq)
{
        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;

        vcpu->stat.inject_pfault_init++;
        VCPU_EVENT(vcpu, 4, "inject: pfault init parameter block at 0x%llx",
                   irq->u.ext.ext_params2);
        trace_kvm_s390_inject_vcpu(vcpu->vcpu_id, KVM_S390_INT_PFAULT_INIT,
                                   irq->u.ext.ext_params,
                                   irq->u.ext.ext_params2);

        li->irq.ext = irq->u.ext;
        set_bit(IRQ_PEND_PFAULT_INIT, &li->pending_irqs);
        kvm_s390_set_cpuflags(vcpu, CPUSTAT_EXT_INT);
        return 0;
}

static int __inject_extcall(struct kvm_vcpu *vcpu, struct kvm_s390_irq *irq)
{
        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
        struct kvm_s390_extcall_info *extcall = &li->irq.extcall;
        uint16_t src_id = irq->u.extcall.code;

        vcpu->stat.inject_external_call++;
        VCPU_EVENT(vcpu, 4, "inject: external call source-cpu:%u",
                   src_id);
        trace_kvm_s390_inject_vcpu(vcpu->vcpu_id, KVM_S390_INT_EXTERNAL_CALL,
                                   src_id, 0);

        /* sending vcpu invalid */
        if (kvm_get_vcpu_by_id(vcpu->kvm, src_id) == NULL)
                return -EINVAL;

        if (kvm_s390_use_sca_entries() && !kvm_s390_pv_cpu_get_handle(vcpu))
                return sca_inject_ext_call(vcpu, src_id);

        if (test_and_set_bit(IRQ_PEND_EXT_EXTERNAL, &li->pending_irqs))
                return -EBUSY;
        *extcall = irq->u.extcall;
        kvm_s390_set_cpuflags(vcpu, CPUSTAT_EXT_INT);
        return 0;
}

static int __inject_set_prefix(struct kvm_vcpu *vcpu, struct kvm_s390_irq *irq)
{
        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
        struct kvm_s390_prefix_info *prefix = &li->irq.prefix;

        vcpu->stat.inject_set_prefix++;
        VCPU_EVENT(vcpu, 3, "inject: set prefix to %x",
                   irq->u.prefix.address);
        trace_kvm_s390_inject_vcpu(vcpu->vcpu_id, KVM_S390_SIGP_SET_PREFIX,
                                   irq->u.prefix.address, 0);

        if (!is_vcpu_stopped(vcpu))
                return -EBUSY;

        *prefix = irq->u.prefix;
        set_bit(IRQ_PEND_SET_PREFIX, &li->pending_irqs);
        return 0;
}

#define KVM_S390_STOP_SUPP_FLAGS (KVM_S390_STOP_FLAG_STORE_STATUS)
static int __inject_sigp_stop(struct kvm_vcpu *vcpu, struct kvm_s390_irq *irq)
{
        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
        struct kvm_s390_stop_info *stop = &li->irq.stop;
        int rc = 0;

        vcpu->stat.inject_stop_signal++;
        trace_kvm_s390_inject_vcpu(vcpu->vcpu_id, KVM_S390_SIGP_STOP, 0, 0);

        if (irq->u.stop.flags & ~KVM_S390_STOP_SUPP_FLAGS)
                return -EINVAL;

        if (is_vcpu_stopped(vcpu)) {
                if (irq->u.stop.flags & KVM_S390_STOP_FLAG_STORE_STATUS)
                        rc = kvm_s390_store_status_unloaded(vcpu,
                                                KVM_S390_STORE_STATUS_NOADDR);
                return rc;
        }

        if (test_and_set_bit(IRQ_PEND_SIGP_STOP, &li->pending_irqs))
                return -EBUSY;
        stop->flags = irq->u.stop.flags;
        kvm_s390_set_cpuflags(vcpu, CPUSTAT_STOP_INT);
        return 0;
}

static int __inject_sigp_restart(struct kvm_vcpu *vcpu)
{
        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;

        vcpu->stat.inject_restart++;
        VCPU_EVENT(vcpu, 3, "%s", "inject: restart int");
        trace_kvm_s390_inject_vcpu(vcpu->vcpu_id, KVM_S390_RESTART, 0, 0);

        set_bit(IRQ_PEND_RESTART, &li->pending_irqs);
        return 0;
}

static int __inject_sigp_emergency(struct kvm_vcpu *vcpu,
                                   struct kvm_s390_irq *irq)
{
        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;

        vcpu->stat.inject_emergency_signal++;
        VCPU_EVENT(vcpu, 4, "inject: emergency from cpu %u",
                   irq->u.emerg.code);
        trace_kvm_s390_inject_vcpu(vcpu->vcpu_id, KVM_S390_INT_EMERGENCY,
                                   irq->u.emerg.code, 0);

        /* sending vcpu invalid */
        if (kvm_get_vcpu_by_id(vcpu->kvm, irq->u.emerg.code) == NULL)
                return -EINVAL;

        set_bit(irq->u.emerg.code, li->sigp_emerg_pending);
        set_bit(IRQ_PEND_EXT_EMERGENCY, &li->pending_irqs);
        kvm_s390_set_cpuflags(vcpu, CPUSTAT_EXT_INT);
        return 0;
}

static int __inject_mchk(struct kvm_vcpu *vcpu, struct kvm_s390_irq *irq)
{
        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
        struct kvm_s390_mchk_info *mchk = &li->irq.mchk;

        vcpu->stat.inject_mchk++;
        VCPU_EVENT(vcpu, 3, "inject: machine check mcic 0x%llx",
                   irq->u.mchk.mcic);
        trace_kvm_s390_inject_vcpu(vcpu->vcpu_id, KVM_S390_MCHK, 0,
                                   irq->u.mchk.mcic);

        /*
         * Because repressible machine checks can be indicated along with
         * exigent machine checks (PoP, Chapter 11, Interruption action)
         * we need to combine cr14, mcic and external damage code.
         * Failing storage address and the logout area should not be or'ed
         * together, we just indicate the last occurrence of the corresponding
         * machine check
         */
        mchk->cr14 |= irq->u.mchk.cr14;
        mchk->mcic |= irq->u.mchk.mcic;
        mchk->ext_damage_code |= irq->u.mchk.ext_damage_code;
        mchk->failing_storage_address = irq->u.mchk.failing_storage_address;
        memcpy(&mchk->fixed_logout, &irq->u.mchk.fixed_logout,
               sizeof(mchk->fixed_logout));
        if (mchk->mcic & MCHK_EX_MASK)
                set_bit(IRQ_PEND_MCHK_EX, &li->pending_irqs);
        else if (mchk->mcic & MCHK_REP_MASK)
                set_bit(IRQ_PEND_MCHK_REP,  &li->pending_irqs);
        return 0;
}

static int __inject_ckc(struct kvm_vcpu *vcpu)
{
        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;

        vcpu->stat.inject_ckc++;
        VCPU_EVENT(vcpu, 3, "%s", "inject: clock comparator external");
        trace_kvm_s390_inject_vcpu(vcpu->vcpu_id, KVM_S390_INT_CLOCK_COMP,
                                   0, 0);

        set_bit(IRQ_PEND_EXT_CLOCK_COMP, &li->pending_irqs);
        kvm_s390_set_cpuflags(vcpu, CPUSTAT_EXT_INT);
        return 0;
}

static int __inject_cpu_timer(struct kvm_vcpu *vcpu)
{
        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;

        vcpu->stat.inject_cputm++;
        VCPU_EVENT(vcpu, 3, "%s", "inject: cpu timer external");
        trace_kvm_s390_inject_vcpu(vcpu->vcpu_id, KVM_S390_INT_CPU_TIMER,
                                   0, 0);

        set_bit(IRQ_PEND_EXT_CPU_TIMER, &li->pending_irqs);
        kvm_s390_set_cpuflags(vcpu, CPUSTAT_EXT_INT);
        return 0;
}

static struct kvm_s390_interrupt_info *get_io_int(struct kvm *kvm,
                                                  int isc, u32 schid)
{
        struct kvm_s390_float_interrupt *fi = &kvm->arch.float_int;
        struct list_head *isc_list = &fi->lists[FIRQ_LIST_IO_ISC_0 + isc];
        struct kvm_s390_interrupt_info *iter;
        u16 id = (schid & 0xffff0000U) >> 16;
        u16 nr = schid & 0x0000ffffU;

        spin_lock(&fi->lock);
        list_for_each_entry(iter, isc_list, list) {
                if (schid && (id != iter->io.subchannel_id ||
                              nr != iter->io.subchannel_nr))
                        continue;
                /* found an appropriate entry */
                list_del_init(&iter->list);
                fi->counters[FIRQ_CNTR_IO] -= 1;
                if (list_empty(isc_list))
                        clear_bit(isc_to_irq_type(isc), &fi->pending_irqs);
                spin_unlock(&fi->lock);
                return iter;
        }
        spin_unlock(&fi->lock);
        return NULL;
}

static struct kvm_s390_interrupt_info *get_top_io_int(struct kvm *kvm,
                                                      u64 isc_mask, u32 schid)
{
        struct kvm_s390_interrupt_info *inti = NULL;
        int isc;

        for (isc = 0; isc <= MAX_ISC && !inti; isc++) {
                if (isc_mask & isc_to_isc_bits(isc))
                        inti = get_io_int(kvm, isc, schid);
        }
        return inti;
}

static int get_top_gisa_isc(struct kvm *kvm, u64 isc_mask, u32 schid)
{
        struct kvm_s390_gisa_interrupt *gi = &kvm->arch.gisa_int;
        unsigned long active_mask;
        int isc;

        if (schid)
                goto out;
        if (!gi->origin)
                goto out;

        active_mask = (isc_mask & gisa_get_ipm(gi->origin) << 24) << 32;
        while (active_mask) {
                isc = __fls(active_mask) ^ (BITS_PER_LONG - 1);
                if (gisa_tac_ipm_gisc(gi->origin, isc))
                        return isc;
                clear_bit_inv(isc, &active_mask);
        }
out:
        return -EINVAL;
}

/*
 * Dequeue and return an I/O interrupt matching any of the interruption
 * subclasses as designated by the isc mask in cr6 and the schid (if != 0).
 * Take into account the interrupts pending in the interrupt list and in GISA.
 *
 * Note that for a guest that does not enable I/O interrupts
 * but relies on TPI, a flood of classic interrupts may starve
 * out adapter interrupts on the same isc. Linux does not do
 * that, and it is possible to work around the issue by configuring
 * different iscs for classic and adapter interrupts in the guest,
 * but we may want to revisit this in the future.
 */
struct kvm_s390_interrupt_info *kvm_s390_get_io_int(struct kvm *kvm,
                                                    u64 isc_mask, u32 schid)
{
        struct kvm_s390_gisa_interrupt *gi = &kvm->arch.gisa_int;
        struct kvm_s390_interrupt_info *inti, *tmp_inti;
        int isc;

        inti = get_top_io_int(kvm, isc_mask, schid);

        isc = get_top_gisa_isc(kvm, isc_mask, schid);
        if (isc < 0)
                /* no AI in GISA */
                goto out;

        if (!inti)
                /* AI in GISA but no classical IO int */
                goto gisa_out;

        /* both types of interrupts present */
        if (int_word_to_isc(inti->io.io_int_word) <= isc) {
                /* classical IO int with higher priority */
                gisa_set_ipm_gisc(gi->origin, isc);
                goto out;
        }
gisa_out:
        tmp_inti = kzalloc_obj(*inti, GFP_KERNEL_ACCOUNT);
        if (tmp_inti) {
                tmp_inti->type = KVM_S390_INT_IO(1, 0, 0, 0);
                tmp_inti->io.io_int_word = isc_to_int_word(isc);
                if (inti)
                        kvm_s390_reinject_io_int(kvm, inti);
                inti = tmp_inti;
        } else
                gisa_set_ipm_gisc(gi->origin, isc);
out:
        return inti;
}

static int __inject_service(struct kvm *kvm,
                             struct kvm_s390_interrupt_info *inti)
{
        struct kvm_s390_float_interrupt *fi = &kvm->arch.float_int;

        kvm->stat.inject_service_signal++;
        spin_lock(&fi->lock);
        fi->srv_signal.ext_params |= inti->ext.ext_params & SCCB_EVENT_PENDING;

        /* We always allow events, track them separately from the sccb ints */
        if (fi->srv_signal.ext_params & SCCB_EVENT_PENDING)
                set_bit(IRQ_PEND_EXT_SERVICE_EV, &fi->pending_irqs);

        /*
         * Early versions of the QEMU s390 bios will inject several
         * service interrupts after another without handling a
         * condition code indicating busy.
         * We will silently ignore those superfluous sccb values.
         * A future version of QEMU will take care of serialization
         * of servc requests
         */
        if (fi->srv_signal.ext_params & SCCB_MASK)
                goto out;
        fi->srv_signal.ext_params |= inti->ext.ext_params & SCCB_MASK;
        set_bit(IRQ_PEND_EXT_SERVICE, &fi->pending_irqs);
out:
        spin_unlock(&fi->lock);
        kfree(inti);
        return 0;
}

static int __inject_virtio(struct kvm *kvm,
                            struct kvm_s390_interrupt_info *inti)
{
        struct kvm_s390_float_interrupt *fi = &kvm->arch.float_int;

        kvm->stat.inject_virtio++;
        spin_lock(&fi->lock);
        if (fi->counters[FIRQ_CNTR_VIRTIO] >= KVM_S390_MAX_VIRTIO_IRQS) {
                spin_unlock(&fi->lock);
                return -EBUSY;
        }
        fi->counters[FIRQ_CNTR_VIRTIO] += 1;
        list_add_tail(&inti->list, &fi->lists[FIRQ_LIST_VIRTIO]);
        set_bit(IRQ_PEND_VIRTIO, &fi->pending_irqs);
        spin_unlock(&fi->lock);
        return 0;
}

static int __inject_pfault_done(struct kvm *kvm,
                                 struct kvm_s390_interrupt_info *inti)
{
        struct kvm_s390_float_interrupt *fi = &kvm->arch.float_int;

        kvm->stat.inject_pfault_done++;
        spin_lock(&fi->lock);
        if (fi->counters[FIRQ_CNTR_PFAULT] >=
                (ASYNC_PF_PER_VCPU * KVM_MAX_VCPUS)) {
                spin_unlock(&fi->lock);
                return -EBUSY;
        }
        fi->counters[FIRQ_CNTR_PFAULT] += 1;
        list_add_tail(&inti->list, &fi->lists[FIRQ_LIST_PFAULT]);
        set_bit(IRQ_PEND_PFAULT_DONE, &fi->pending_irqs);
        spin_unlock(&fi->lock);
        return 0;
}

#define CR_PENDING_SUBCLASS 28
static int __inject_float_mchk(struct kvm *kvm,
                                struct kvm_s390_interrupt_info *inti)
{
        struct kvm_s390_float_interrupt *fi = &kvm->arch.float_int;

        kvm->stat.inject_float_mchk++;
        spin_lock(&fi->lock);
        fi->mchk.cr14 |= inti->mchk.cr14 & (1UL << CR_PENDING_SUBCLASS);
        fi->mchk.mcic |= inti->mchk.mcic;
        set_bit(IRQ_PEND_MCHK_REP, &fi->pending_irqs);
        spin_unlock(&fi->lock);
        kfree(inti);
        return 0;
}

static int __inject_io(struct kvm *kvm, struct kvm_s390_interrupt_info *inti)
{
        struct kvm_s390_gisa_interrupt *gi = &kvm->arch.gisa_int;
        struct kvm_s390_float_interrupt *fi;
        struct list_head *list;
        int isc;

        kvm->stat.inject_io++;
        isc = int_word_to_isc(inti->io.io_int_word);

        /*
         * We do not use the lock checking variant as this is just a
         * performance optimization and we do not hold the lock here.
         * This is ok as the code will pick interrupts from both "lists"
         * for delivery.
         */
        if (gi->origin && inti->type & KVM_S390_INT_IO_AI_MASK) {
                VM_EVENT(kvm, 4, "%s isc %1u", "inject: I/O (AI/gisa)", isc);
                gisa_set_ipm_gisc(gi->origin, isc);
                kfree(inti);
                return 0;
        }

        fi = &kvm->arch.float_int;
        spin_lock(&fi->lock);
        if (fi->counters[FIRQ_CNTR_IO] >= KVM_S390_MAX_FLOAT_IRQS) {
                spin_unlock(&fi->lock);
                return -EBUSY;
        }
        fi->counters[FIRQ_CNTR_IO] += 1;

        if (inti->type & KVM_S390_INT_IO_AI_MASK)
                VM_EVENT(kvm, 4, "%s", "inject: I/O (AI)");
        else
                VM_EVENT(kvm, 4, "inject: I/O %x ss %x schid %04x",
                        inti->io.subchannel_id >> 8,
                        inti->io.subchannel_id >> 1 & 0x3,
                        inti->io.subchannel_nr);
        list = &fi->lists[FIRQ_LIST_IO_ISC_0 + isc];
        list_add_tail(&inti->list, list);
        set_bit(isc_to_irq_type(isc), &fi->pending_irqs);
        spin_unlock(&fi->lock);
        return 0;
}

/*
 * Find a destination VCPU for a floating irq and kick it.
 */
static void __floating_irq_kick(struct kvm *kvm, u64 type)
{
        struct kvm_vcpu *dst_vcpu;
        int sigcpu, online_vcpus, nr_tries = 0;

        online_vcpus = atomic_read(&kvm->online_vcpus);
        if (!online_vcpus)
                return;

        for (sigcpu = kvm->arch.float_int.last_sleep_cpu; ; sigcpu++) {
                sigcpu %= online_vcpus;
                dst_vcpu = kvm_get_vcpu(kvm, sigcpu);
                if (!is_vcpu_stopped(dst_vcpu))
                        break;
                /* avoid endless loops if all vcpus are stopped */
                if (nr_tries++ >= online_vcpus)
                        return;
        }

        /* make the VCPU drop out of the SIE, or wake it up if sleeping */
        switch (type) {
        case KVM_S390_MCHK:
                kvm_s390_set_cpuflags(dst_vcpu, CPUSTAT_STOP_INT);
                break;
        case KVM_S390_INT_IO_MIN...KVM_S390_INT_IO_MAX:
                if (!(type & KVM_S390_INT_IO_AI_MASK &&
                      kvm->arch.gisa_int.origin) ||
                      kvm_s390_pv_cpu_get_handle(dst_vcpu))
                        kvm_s390_set_cpuflags(dst_vcpu, CPUSTAT_IO_INT);
                break;
        default:
                kvm_s390_set_cpuflags(dst_vcpu, CPUSTAT_EXT_INT);
                break;
        }
        kvm_s390_vcpu_wakeup(dst_vcpu);
}

static int __inject_vm(struct kvm *kvm, struct kvm_s390_interrupt_info *inti)
{
        u64 type = READ_ONCE(inti->type);
        int rc;

        switch (type) {
        case KVM_S390_MCHK:
                rc = __inject_float_mchk(kvm, inti);
                break;
        case KVM_S390_INT_VIRTIO:
                rc = __inject_virtio(kvm, inti);
                break;
        case KVM_S390_INT_SERVICE:
                rc = __inject_service(kvm, inti);
                break;
        case KVM_S390_INT_PFAULT_DONE:
                rc = __inject_pfault_done(kvm, inti);
                break;
        case KVM_S390_INT_IO_MIN...KVM_S390_INT_IO_MAX:
                rc = __inject_io(kvm, inti);
                break;
        default:
                rc = -EINVAL;
        }
        if (rc)
                return rc;

        __floating_irq_kick(kvm, type);
        return 0;
}

int kvm_s390_inject_vm(struct kvm *kvm,
                       struct kvm_s390_interrupt *s390int)
{
        struct kvm_s390_interrupt_info *inti;
        int rc;

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

        inti->type = s390int->type;
        switch (inti->type) {
        case KVM_S390_INT_VIRTIO:
                VM_EVENT(kvm, 5, "inject: virtio parm:%x,parm64:%llx",
                         s390int->parm, s390int->parm64);
                inti->ext.ext_params = s390int->parm;
                inti->ext.ext_params2 = s390int->parm64;
                break;
        case KVM_S390_INT_SERVICE:
                VM_EVENT(kvm, 4, "inject: sclp parm:%x", s390int->parm);
                inti->ext.ext_params = s390int->parm;
                break;
        case KVM_S390_INT_PFAULT_DONE:
                inti->ext.ext_params2 = s390int->parm64;
                break;
        case KVM_S390_MCHK:
                VM_EVENT(kvm, 3, "inject: machine check mcic 0x%llx",
                         s390int->parm64);
                inti->mchk.cr14 = s390int->parm; /* upper bits are not used */
                inti->mchk.mcic = s390int->parm64;
                break;
        case KVM_S390_INT_IO_MIN...KVM_S390_INT_IO_MAX:
                inti->io.subchannel_id = s390int->parm >> 16;
                inti->io.subchannel_nr = s390int->parm & 0x0000ffffu;
                inti->io.io_int_parm = s390int->parm64 >> 32;
                inti->io.io_int_word = s390int->parm64 & 0x00000000ffffffffull;
                break;
        default:
                kfree(inti);
                return -EINVAL;
        }
        trace_kvm_s390_inject_vm(s390int->type, s390int->parm, s390int->parm64,
                                 2);

        rc = __inject_vm(kvm, inti);
        if (rc)
                kfree(inti);
        return rc;
}

int kvm_s390_reinject_io_int(struct kvm *kvm,
                              struct kvm_s390_interrupt_info *inti)
{
        return __inject_vm(kvm, inti);
}

int s390int_to_s390irq(struct kvm_s390_interrupt *s390int,
                       struct kvm_s390_irq *irq)
{
        irq->type = s390int->type;
        switch (irq->type) {
        case KVM_S390_PROGRAM_INT:
                if (s390int->parm & 0xffff0000)
                        return -EINVAL;
                irq->u.pgm.code = s390int->parm;
                break;
        case KVM_S390_SIGP_SET_PREFIX:
                irq->u.prefix.address = s390int->parm;
                break;
        case KVM_S390_SIGP_STOP:
                irq->u.stop.flags = s390int->parm;
                break;
        case KVM_S390_INT_EXTERNAL_CALL:
                if (s390int->parm & 0xffff0000)
                        return -EINVAL;
                irq->u.extcall.code = s390int->parm;
                break;
        case KVM_S390_INT_EMERGENCY:
                if (s390int->parm & 0xffff0000)
                        return -EINVAL;
                irq->u.emerg.code = s390int->parm;
                break;
        case KVM_S390_MCHK:
                irq->u.mchk.mcic = s390int->parm64;
                break;
        case KVM_S390_INT_PFAULT_INIT:
                irq->u.ext.ext_params = s390int->parm;
                irq->u.ext.ext_params2 = s390int->parm64;
                break;
        case KVM_S390_RESTART:
        case KVM_S390_INT_CLOCK_COMP:
        case KVM_S390_INT_CPU_TIMER:
                break;
        default:
                return -EINVAL;
        }
        return 0;
}

int kvm_s390_is_stop_irq_pending(struct kvm_vcpu *vcpu)
{
        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;

        return test_bit(IRQ_PEND_SIGP_STOP, &li->pending_irqs);
}

int kvm_s390_is_restart_irq_pending(struct kvm_vcpu *vcpu)
{
        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;

        return test_bit(IRQ_PEND_RESTART, &li->pending_irqs);
}

void kvm_s390_clear_stop_irq(struct kvm_vcpu *vcpu)
{
        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;

        spin_lock(&li->lock);
        li->irq.stop.flags = 0;
        clear_bit(IRQ_PEND_SIGP_STOP, &li->pending_irqs);
        spin_unlock(&li->lock);
}

static int do_inject_vcpu(struct kvm_vcpu *vcpu, struct kvm_s390_irq *irq)
{
        int rc;

        switch (irq->type) {
        case KVM_S390_PROGRAM_INT:
                rc = __inject_prog(vcpu, irq);
                break;
        case KVM_S390_SIGP_SET_PREFIX:
                rc = __inject_set_prefix(vcpu, irq);
                break;
        case KVM_S390_SIGP_STOP:
                rc = __inject_sigp_stop(vcpu, irq);
                break;
        case KVM_S390_RESTART:
                rc = __inject_sigp_restart(vcpu);
                break;
        case KVM_S390_INT_CLOCK_COMP:
                rc = __inject_ckc(vcpu);
                break;
        case KVM_S390_INT_CPU_TIMER:
                rc = __inject_cpu_timer(vcpu);
                break;
        case KVM_S390_INT_EXTERNAL_CALL:
                rc = __inject_extcall(vcpu, irq);
                break;
        case KVM_S390_INT_EMERGENCY:
                rc = __inject_sigp_emergency(vcpu, irq);
                break;
        case KVM_S390_MCHK:
                rc = __inject_mchk(vcpu, irq);
                break;
        case KVM_S390_INT_PFAULT_INIT:
                rc = __inject_pfault_init(vcpu, irq);
                break;
        case KVM_S390_INT_VIRTIO:
        case KVM_S390_INT_SERVICE:
        case KVM_S390_INT_IO_MIN...KVM_S390_INT_IO_MAX:
        default:
                rc = -EINVAL;
        }

        return rc;
}

int kvm_s390_inject_vcpu(struct kvm_vcpu *vcpu, struct kvm_s390_irq *irq)
{
        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
        int rc;

        spin_lock(&li->lock);
        rc = do_inject_vcpu(vcpu, irq);
        spin_unlock(&li->lock);
        if (!rc)
                kvm_s390_vcpu_wakeup(vcpu);
        return rc;
}

static inline void clear_irq_list(struct list_head *_list)
{
        struct kvm_s390_interrupt_info *inti, *n;

        list_for_each_entry_safe(inti, n, _list, list) {
                list_del(&inti->list);
                kfree(inti);
        }
}

static void inti_to_irq(struct kvm_s390_interrupt_info *inti,
                       struct kvm_s390_irq *irq)
{
        irq->type = inti->type;
        switch (inti->type) {
        case KVM_S390_INT_PFAULT_INIT:
        case KVM_S390_INT_PFAULT_DONE:
        case KVM_S390_INT_VIRTIO:
                irq->u.ext = inti->ext;
                break;
        case KVM_S390_INT_IO_MIN...KVM_S390_INT_IO_MAX:
                irq->u.io = inti->io;
                break;
        }
}

void kvm_s390_clear_float_irqs(struct kvm *kvm)
{
        struct kvm_s390_float_interrupt *fi = &kvm->arch.float_int;
        int i;

        mutex_lock(&kvm->lock);
        if (!kvm_s390_pv_is_protected(kvm))
                fi->masked_irqs = 0;
        mutex_unlock(&kvm->lock);
        spin_lock(&fi->lock);
        fi->pending_irqs = 0;
        memset(&fi->srv_signal, 0, sizeof(fi->srv_signal));
        memset(&fi->mchk, 0, sizeof(fi->mchk));
        for (i = 0; i < FIRQ_LIST_COUNT; i++)
                clear_irq_list(&fi->lists[i]);
        for (i = 0; i < FIRQ_MAX_COUNT; i++)
                fi->counters[i] = 0;
        spin_unlock(&fi->lock);
        kvm_s390_gisa_clear(kvm);
};

static int get_all_floating_irqs(struct kvm *kvm, u8 __user *usrbuf, u64 len)
{
        struct kvm_s390_gisa_interrupt *gi = &kvm->arch.gisa_int;
        struct kvm_s390_interrupt_info *inti;
        struct kvm_s390_float_interrupt *fi;
        struct kvm_s390_irq *buf;
        struct kvm_s390_irq *irq;
        int max_irqs;
        int ret = 0;
        int n = 0;
        int i;

        if (len > KVM_S390_FLIC_MAX_BUFFER || len == 0)
                return -EINVAL;

        /*
         * We are already using -ENOMEM to signal
         * userspace it may retry with a bigger buffer,
         * so we need to use something else for this case
         */
        buf = vzalloc(len);
        if (!buf)
                return -ENOBUFS;

        max_irqs = len / sizeof(struct kvm_s390_irq);

        if (gi->origin && gisa_get_ipm(gi->origin)) {
                for (i = 0; i <= MAX_ISC; i++) {
                        if (n == max_irqs) {
                                /* signal userspace to try again */
                                ret = -ENOMEM;
                                goto out_nolock;
                        }
                        if (gisa_tac_ipm_gisc(gi->origin, i)) {
                                irq = (struct kvm_s390_irq *) &buf[n];
                                irq->type = KVM_S390_INT_IO(1, 0, 0, 0);
                                irq->u.io.io_int_word = isc_to_int_word(i);
                                n++;
                        }
                }
        }
        fi = &kvm->arch.float_int;
        spin_lock(&fi->lock);
        for (i = 0; i < FIRQ_LIST_COUNT; i++) {
                list_for_each_entry(inti, &fi->lists[i], list) {
                        if (n == max_irqs) {
                                /* signal userspace to try again */
                                ret = -ENOMEM;
                                goto out;
                        }
                        inti_to_irq(inti, &buf[n]);
                        n++;
                }
        }
        if (test_bit(IRQ_PEND_EXT_SERVICE, &fi->pending_irqs) ||
            test_bit(IRQ_PEND_EXT_SERVICE_EV, &fi->pending_irqs)) {
                if (n == max_irqs) {
                        /* signal userspace to try again */
                        ret = -ENOMEM;
                        goto out;
                }
                irq = (struct kvm_s390_irq *) &buf[n];
                irq->type = KVM_S390_INT_SERVICE;
                irq->u.ext = fi->srv_signal;
                n++;
        }
        if (test_bit(IRQ_PEND_MCHK_REP, &fi->pending_irqs)) {
                if (n == max_irqs) {
                                /* signal userspace to try again */
                                ret = -ENOMEM;
                                goto out;
                }
                irq = (struct kvm_s390_irq *) &buf[n];
                irq->type = KVM_S390_MCHK;
                irq->u.mchk = fi->mchk;
                n++;
}

out:
        spin_unlock(&fi->lock);
out_nolock:
        if (!ret && n > 0) {
                if (copy_to_user(usrbuf, buf, sizeof(struct kvm_s390_irq) * n))
                        ret = -EFAULT;
        }
        vfree(buf);

        return ret < 0 ? ret : n;
}

static int flic_ais_mode_get_all(struct kvm *kvm, struct kvm_device_attr *attr)
{
        struct kvm_s390_float_interrupt *fi = &kvm->arch.float_int;
        struct kvm_s390_ais_all ais;

        if (attr->attr < sizeof(ais))
                return -EINVAL;

        if (!test_kvm_facility(kvm, 72))
                return -EOPNOTSUPP;

        mutex_lock(&fi->ais_lock);
        ais.simm = fi->simm;
        ais.nimm = fi->nimm;
        mutex_unlock(&fi->ais_lock);

        if (copy_to_user((void __user *)attr->addr, &ais, sizeof(ais)))
                return -EFAULT;

        return 0;
}

static int flic_get_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
{
        int r;

        switch (attr->group) {
        case KVM_DEV_FLIC_GET_ALL_IRQS:
                r = get_all_floating_irqs(dev->kvm, (u8 __user *) attr->addr,
                                          attr->attr);
                break;
        case KVM_DEV_FLIC_AISM_ALL:
                r = flic_ais_mode_get_all(dev->kvm, attr);
                break;
        default:
                r = -EINVAL;
        }

        return r;
}

static inline int copy_irq_from_user(struct kvm_s390_interrupt_info *inti,
                                     u64 addr)
{
        struct kvm_s390_irq __user *uptr = (struct kvm_s390_irq __user *) addr;
        void *target = NULL;
        void __user *source;
        u64 size;

        if (get_user(inti->type, (u64 __user *)addr))
                return -EFAULT;

        switch (inti->type) {
        case KVM_S390_INT_PFAULT_INIT:
        case KVM_S390_INT_PFAULT_DONE:
        case KVM_S390_INT_VIRTIO:
        case KVM_S390_INT_SERVICE:
                target = (void *) &inti->ext;
                source = &uptr->u.ext;
                size = sizeof(inti->ext);
                break;
        case KVM_S390_INT_IO_MIN...KVM_S390_INT_IO_MAX:
                target = (void *) &inti->io;
                source = &uptr->u.io;
                size = sizeof(inti->io);
                break;
        case KVM_S390_MCHK:
                target = (void *) &inti->mchk;
                source = &uptr->u.mchk;
                size = sizeof(inti->mchk);
                break;
        default:
                return -EINVAL;
        }

        if (copy_from_user(target, source, size))
                return -EFAULT;

        return 0;
}

static int enqueue_floating_irq(struct kvm_device *dev,
                                struct kvm_device_attr *attr)
{
        struct kvm_s390_interrupt_info *inti = NULL;
        int r = 0;
        int len = attr->attr;

        if (len % sizeof(struct kvm_s390_irq) != 0)
                return -EINVAL;
        else if (len > KVM_S390_FLIC_MAX_BUFFER)
                return -EINVAL;

        while (len >= sizeof(struct kvm_s390_irq)) {
                inti = kzalloc_obj(*inti, GFP_KERNEL_ACCOUNT);
                if (!inti)
                        return -ENOMEM;

                r = copy_irq_from_user(inti, attr->addr);
                if (r) {
                        kfree(inti);
                        return r;
                }
                r = __inject_vm(dev->kvm, inti);
                if (r) {
                        kfree(inti);
                        return r;
                }
                len -= sizeof(struct kvm_s390_irq);
                attr->addr += sizeof(struct kvm_s390_irq);
        }

        return r;
}

static struct s390_io_adapter *get_io_adapter(struct kvm *kvm, unsigned int id)
{
        if (id >= MAX_S390_IO_ADAPTERS)
                return NULL;
        id = array_index_nospec(id, MAX_S390_IO_ADAPTERS);
        return kvm->arch.adapters[id];
}

static int register_io_adapter(struct kvm_device *dev,
                               struct kvm_device_attr *attr)
{
        struct s390_io_adapter *adapter;
        struct kvm_s390_io_adapter adapter_info;

        if (copy_from_user(&adapter_info,
                           (void __user *)attr->addr, sizeof(adapter_info)))
                return -EFAULT;

        if (adapter_info.id >= MAX_S390_IO_ADAPTERS)
                return -EINVAL;

        adapter_info.id = array_index_nospec(adapter_info.id,
                                             MAX_S390_IO_ADAPTERS);

        if (dev->kvm->arch.adapters[adapter_info.id] != NULL)
                return -EINVAL;

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

        adapter->id = adapter_info.id;
        adapter->isc = adapter_info.isc;
        adapter->maskable = adapter_info.maskable;
        adapter->masked = false;
        adapter->swap = adapter_info.swap;
        adapter->suppressible = (adapter_info.flags) &
                                KVM_S390_ADAPTER_SUPPRESSIBLE;
        dev->kvm->arch.adapters[adapter->id] = adapter;

        return 0;
}

int kvm_s390_mask_adapter(struct kvm *kvm, unsigned int id, bool masked)
{
        int ret;
        struct s390_io_adapter *adapter = get_io_adapter(kvm, id);

        if (!adapter || !adapter->maskable)
                return -EINVAL;
        ret = adapter->masked;
        adapter->masked = masked;
        return ret;
}

void kvm_s390_destroy_adapters(struct kvm *kvm)
{
        int i;

        for (i = 0; i < MAX_S390_IO_ADAPTERS; i++)
                kfree(kvm->arch.adapters[i]);
}

static int modify_io_adapter(struct kvm_device *dev,
                             struct kvm_device_attr *attr)
{
        struct kvm_s390_io_adapter_req req;
        struct s390_io_adapter *adapter;
        int ret;

        if (copy_from_user(&req, (void __user *)attr->addr, sizeof(req)))
                return -EFAULT;

        adapter = get_io_adapter(dev->kvm, req.id);
        if (!adapter)
                return -EINVAL;
        switch (req.type) {
        case KVM_S390_IO_ADAPTER_MASK:
                ret = kvm_s390_mask_adapter(dev->kvm, req.id, req.mask);
                if (ret > 0)
                        ret = 0;
                break;
        /*
         * The following operations are no longer needed and therefore no-ops.
         * The gpa to hva translation is done when an IRQ route is set up. The
         * set_irq code uses get_user_pages_remote() to do the actual write.
         */
        case KVM_S390_IO_ADAPTER_MAP:
        case KVM_S390_IO_ADAPTER_UNMAP:
                ret = 0;
                break;
        default:
                ret = -EINVAL;
        }

        return ret;
}

static int clear_io_irq(struct kvm *kvm, struct kvm_device_attr *attr)

{
        const u64 isc_mask = 0xffUL << 24; /* all iscs set */
        u32 schid;

        if (attr->flags)
                return -EINVAL;
        if (attr->attr != sizeof(schid))
                return -EINVAL;
        if (copy_from_user(&schid, (void __user *) attr->addr, sizeof(schid)))
                return -EFAULT;
        if (!schid)
                return -EINVAL;
        kfree(kvm_s390_get_io_int(kvm, isc_mask, schid));
        /*
         * If userspace is conforming to the architecture, we can have at most
         * one pending I/O interrupt per subchannel, so this is effectively a
         * clear all.
         */
        return 0;
}

static int modify_ais_mode(struct kvm *kvm, struct kvm_device_attr *attr)
{
        struct kvm_s390_float_interrupt *fi = &kvm->arch.float_int;
        struct kvm_s390_ais_req req;
        int ret = 0;

        if (!test_kvm_facility(kvm, 72))
                return -EOPNOTSUPP;

        if (copy_from_user(&req, (void __user *)attr->addr, sizeof(req)))
                return -EFAULT;

        if (req.isc > MAX_ISC)
                return -EINVAL;

        trace_kvm_s390_modify_ais_mode(req.isc,
                                       (fi->simm & AIS_MODE_MASK(req.isc)) ?
                                       (fi->nimm & AIS_MODE_MASK(req.isc)) ?
                                       2 : KVM_S390_AIS_MODE_SINGLE :
                                       KVM_S390_AIS_MODE_ALL, req.mode);

        mutex_lock(&fi->ais_lock);
        switch (req.mode) {
        case KVM_S390_AIS_MODE_ALL:
                fi->simm &= ~AIS_MODE_MASK(req.isc);
                fi->nimm &= ~AIS_MODE_MASK(req.isc);
                break;
        case KVM_S390_AIS_MODE_SINGLE:
                fi->simm |= AIS_MODE_MASK(req.isc);
                fi->nimm &= ~AIS_MODE_MASK(req.isc);
                break;
        default:
                ret = -EINVAL;
        }
        mutex_unlock(&fi->ais_lock);

        return ret;
}

static int kvm_s390_inject_airq(struct kvm *kvm,
                                struct s390_io_adapter *adapter)
{
        struct kvm_s390_float_interrupt *fi = &kvm->arch.float_int;
        struct kvm_s390_interrupt s390int = {
                .type = KVM_S390_INT_IO(1, 0, 0, 0),
                .parm = 0,
                .parm64 = isc_to_int_word(adapter->isc),
        };
        int ret = 0;

        if (!test_kvm_facility(kvm, 72) || !adapter->suppressible)
                return kvm_s390_inject_vm(kvm, &s390int);

        mutex_lock(&fi->ais_lock);
        if (fi->nimm & AIS_MODE_MASK(adapter->isc)) {
                trace_kvm_s390_airq_suppressed(adapter->id, adapter->isc);
                goto out;
        }

        ret = kvm_s390_inject_vm(kvm, &s390int);
        if (!ret && (fi->simm & AIS_MODE_MASK(adapter->isc))) {
                fi->nimm |= AIS_MODE_MASK(adapter->isc);
                trace_kvm_s390_modify_ais_mode(adapter->isc,
                                               KVM_S390_AIS_MODE_SINGLE, 2);
        }
out:
        mutex_unlock(&fi->ais_lock);
        return ret;
}

static int flic_inject_airq(struct kvm *kvm, struct kvm_device_attr *attr)
{
        unsigned int id = attr->attr;
        struct s390_io_adapter *adapter = get_io_adapter(kvm, id);

        if (!adapter)
                return -EINVAL;

        return kvm_s390_inject_airq(kvm, adapter);
}

static int flic_ais_mode_set_all(struct kvm *kvm, struct kvm_device_attr *attr)
{
        struct kvm_s390_float_interrupt *fi = &kvm->arch.float_int;
        struct kvm_s390_ais_all ais;

        if (!test_kvm_facility(kvm, 72))
                return -EOPNOTSUPP;

        if (copy_from_user(&ais, (void __user *)attr->addr, sizeof(ais)))
                return -EFAULT;

        mutex_lock(&fi->ais_lock);
        fi->simm = ais.simm;
        fi->nimm = ais.nimm;
        mutex_unlock(&fi->ais_lock);

        return 0;
}

static int flic_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
{
        int r = 0;
        unsigned long i;
        struct kvm_vcpu *vcpu;

        switch (attr->group) {
        case KVM_DEV_FLIC_ENQUEUE:
                r = enqueue_floating_irq(dev, attr);
                break;
        case KVM_DEV_FLIC_CLEAR_IRQS:
                kvm_s390_clear_float_irqs(dev->kvm);
                break;
        case KVM_DEV_FLIC_APF_ENABLE:
                if (kvm_is_ucontrol(dev->kvm))
                        return -EINVAL;
                set_bit(GMAP_FLAG_PFAULT_ENABLED, &dev->kvm->arch.gmap->flags);
                break;
        case KVM_DEV_FLIC_APF_DISABLE_WAIT:
                if (kvm_is_ucontrol(dev->kvm))
                        return -EINVAL;
                clear_bit(GMAP_FLAG_PFAULT_ENABLED, &dev->kvm->arch.gmap->flags);
                /*
                 * Make sure no async faults are in transition when
                 * clearing the queues. So we don't need to worry
                 * about late coming workers.
                 */
                synchronize_srcu(&dev->kvm->srcu);
                kvm_for_each_vcpu(i, vcpu, dev->kvm)
                        kvm_clear_async_pf_completion_queue(vcpu);
                break;
        case KVM_DEV_FLIC_ADAPTER_REGISTER:
                r = register_io_adapter(dev, attr);
                break;
        case KVM_DEV_FLIC_ADAPTER_MODIFY:
                r = modify_io_adapter(dev, attr);
                break;
        case KVM_DEV_FLIC_CLEAR_IO_IRQ:
                r = clear_io_irq(dev->kvm, attr);
                break;
        case KVM_DEV_FLIC_AISM:
                r = modify_ais_mode(dev->kvm, attr);
                break;
        case KVM_DEV_FLIC_AIRQ_INJECT:
                r = flic_inject_airq(dev->kvm, attr);
                break;
        case KVM_DEV_FLIC_AISM_ALL:
                r = flic_ais_mode_set_all(dev->kvm, attr);
                break;
        default:
                r = -EINVAL;
        }

        return r;
}

static int flic_has_attr(struct kvm_device *dev,
                             struct kvm_device_attr *attr)
{
        switch (attr->group) {
        case KVM_DEV_FLIC_GET_ALL_IRQS:
        case KVM_DEV_FLIC_ENQUEUE:
        case KVM_DEV_FLIC_CLEAR_IRQS:
        case KVM_DEV_FLIC_APF_ENABLE:
        case KVM_DEV_FLIC_APF_DISABLE_WAIT:
        case KVM_DEV_FLIC_ADAPTER_REGISTER:
        case KVM_DEV_FLIC_ADAPTER_MODIFY:
        case KVM_DEV_FLIC_CLEAR_IO_IRQ:
        case KVM_DEV_FLIC_AISM:
        case KVM_DEV_FLIC_AIRQ_INJECT:
        case KVM_DEV_FLIC_AISM_ALL:
                return 0;
        }
        return -ENXIO;
}

static int flic_create(struct kvm_device *dev, u32 type)
{
        if (!dev)
                return -EINVAL;
        if (dev->kvm->arch.flic)
                return -EINVAL;
        dev->kvm->arch.flic = dev;
        return 0;
}

static void flic_destroy(struct kvm_device *dev)
{
        dev->kvm->arch.flic = NULL;
        kfree(dev);
}

/* s390 floating irq controller (flic) */
struct kvm_device_ops kvm_flic_ops = {
        .name = "kvm-flic",
        .get_attr = flic_get_attr,
        .set_attr = flic_set_attr,
        .has_attr = flic_has_attr,
        .create = flic_create,
        .destroy = flic_destroy,
};

static unsigned long get_ind_bit(__u64 addr, unsigned long bit_nr, bool swap)
{
        unsigned long bit;

        bit = bit_nr + (addr % PAGE_SIZE) * 8;

        /* kvm_set_routing_entry() should never allow this to happen */
        WARN_ON_ONCE(bit > (PAGE_SIZE * BITS_PER_BYTE - 1));

        return swap ? (bit ^ (BITS_PER_LONG - 1)) : bit;
}

static struct page *get_map_page(struct kvm *kvm, u64 uaddr)
{
        struct mm_struct *mm = kvm->mm;
        struct page *page = NULL;
        int locked = 1;

        if (mmget_not_zero(mm)) {
                mmap_read_lock(mm);
                get_user_pages_remote(mm, uaddr, 1, FOLL_WRITE,
                                      &page, &locked);
                if (locked)
                        mmap_read_unlock(mm);
                mmput(mm);
        }

        return page;
}

static int adapter_indicators_set(struct kvm *kvm,
                                  struct s390_io_adapter *adapter,
                                  struct kvm_s390_adapter_int *adapter_int)
{
        unsigned long bit;
        int summary_set, idx;
        struct page *ind_page, *summary_page;
        void *map;

        ind_page = get_map_page(kvm, adapter_int->ind_addr);
        if (!ind_page)
                return -1;
        summary_page = get_map_page(kvm, adapter_int->summary_addr);
        if (!summary_page) {
                put_page(ind_page);
                return -1;
        }

        idx = srcu_read_lock(&kvm->srcu);
        map = page_address(ind_page);
        bit = get_ind_bit(adapter_int->ind_addr,
                          adapter_int->ind_offset, adapter->swap);
        set_bit(bit, map);
        mark_page_dirty(kvm, adapter_int->ind_gaddr >> PAGE_SHIFT);
        set_page_dirty_lock(ind_page);
        map = page_address(summary_page);
        bit = get_ind_bit(adapter_int->summary_addr,
                          adapter_int->summary_offset, adapter->swap);
        summary_set = test_and_set_bit(bit, map);
        mark_page_dirty(kvm, adapter_int->summary_gaddr >> PAGE_SHIFT);
        set_page_dirty_lock(summary_page);
        srcu_read_unlock(&kvm->srcu, idx);

        put_page(ind_page);
        put_page(summary_page);
        return summary_set ? 0 : 1;
}

/*
 * < 0 - not injected due to error
 * = 0 - coalesced, summary indicator already active
 * > 0 - injected interrupt
 */
static int set_adapter_int(struct kvm_kernel_irq_routing_entry *e,
                           struct kvm *kvm, int irq_source_id, int level,
                           bool line_status)
{
        int ret;
        struct s390_io_adapter *adapter;

        /* We're only interested in the 0->1 transition. */
        if (!level)
                return 0;
        adapter = get_io_adapter(kvm, e->adapter.adapter_id);
        if (!adapter)
                return -1;
        ret = adapter_indicators_set(kvm, adapter, &e->adapter);
        if ((ret > 0) && !adapter->masked) {
                ret = kvm_s390_inject_airq(kvm, adapter);
                if (ret == 0)
                        ret = 1;
        }
        return ret;
}

/*
 * Inject the machine check to the guest.
 */
void kvm_s390_reinject_machine_check(struct kvm_vcpu *vcpu,
                                     struct mcck_volatile_info *mcck_info)
{
        struct kvm_s390_interrupt_info inti;
        struct kvm_s390_irq irq;
        struct kvm_s390_mchk_info *mchk;
        union mci mci;
        __u64 cr14 = 0;         /* upper bits are not used */
        int rc;

        mci.val = mcck_info->mcic;

        /* log machine checks being reinjected on all debugs */
        VCPU_EVENT(vcpu, 2, "guest machine check %lx", mci.val);
        KVM_EVENT(2, "guest machine check %lx", mci.val);
        pr_info("guest machine check pid %d: %lx", current->pid, mci.val);

        if (mci.sr)
                cr14 |= CR14_RECOVERY_SUBMASK;
        if (mci.dg)
                cr14 |= CR14_DEGRADATION_SUBMASK;
        if (mci.w)
                cr14 |= CR14_WARNING_SUBMASK;

        mchk = mci.ck ? &inti.mchk : &irq.u.mchk;
        mchk->cr14 = cr14;
        mchk->mcic = mcck_info->mcic;
        mchk->ext_damage_code = mcck_info->ext_damage_code;
        mchk->failing_storage_address = mcck_info->failing_storage_address;
        if (mci.ck) {
                /* Inject the floating machine check */
                inti.type = KVM_S390_MCHK;
                rc = __inject_vm(vcpu->kvm, &inti);
        } else {
                /* Inject the machine check to specified vcpu */
                irq.type = KVM_S390_MCHK;
                rc = kvm_s390_inject_vcpu(vcpu, &irq);
        }
        WARN_ON_ONCE(rc);
}

int kvm_set_routing_entry(struct kvm *kvm,
                          struct kvm_kernel_irq_routing_entry *e,
                          const struct kvm_irq_routing_entry *ue)
{
        const struct kvm_irq_routing_s390_adapter *adapter;
        u64 uaddr_s, uaddr_i;
        int idx;

        switch (ue->type) {
        /* we store the userspace addresses instead of the guest addresses */
        case KVM_IRQ_ROUTING_S390_ADAPTER:
                if (kvm_is_ucontrol(kvm))
                        return -EINVAL;
                e->set = set_adapter_int;

                adapter = &ue->u.adapter;
                if (adapter->summary_addr + (adapter->summary_offset / 8) >=
                    (adapter->summary_addr & PAGE_MASK) + PAGE_SIZE)
                        return -EINVAL;
                if (adapter->ind_addr + (adapter->ind_offset / 8) >=
                    (adapter->ind_addr & PAGE_MASK) + PAGE_SIZE)
                        return -EINVAL;

                idx = srcu_read_lock(&kvm->srcu);
                uaddr_s = gpa_to_hva(kvm, ue->u.adapter.summary_addr);
                uaddr_i = gpa_to_hva(kvm, ue->u.adapter.ind_addr);
                srcu_read_unlock(&kvm->srcu, idx);

                if (kvm_is_error_hva(uaddr_s) || kvm_is_error_hva(uaddr_i))
                        return -EFAULT;
                e->adapter.summary_addr = uaddr_s;
                e->adapter.summary_gaddr = ue->u.adapter.summary_addr;
                e->adapter.ind_addr = uaddr_i;
                e->adapter.ind_gaddr = ue->u.adapter.ind_addr;
                e->adapter.summary_offset = ue->u.adapter.summary_offset;
                e->adapter.ind_offset = ue->u.adapter.ind_offset;
                e->adapter.adapter_id = ue->u.adapter.adapter_id;
                return 0;
        default:
                return -EINVAL;
        }
}

int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e, struct kvm *kvm,
                int irq_source_id, int level, bool line_status)
{
        return -EINVAL;
}

int kvm_s390_set_irq_state(struct kvm_vcpu *vcpu, void __user *irqstate, int len)
{
        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
        struct kvm_s390_irq *buf;
        int r = 0;
        int n;

        buf = vmalloc(len);
        if (!buf)
                return -ENOMEM;

        if (copy_from_user((void *) buf, irqstate, len)) {
                r = -EFAULT;
                goto out_free;
        }

        /*
         * Don't allow setting the interrupt state
         * when there are already interrupts pending
         */
        spin_lock(&li->lock);
        if (li->pending_irqs) {
                r = -EBUSY;
                goto out_unlock;
        }

        for (n = 0; n < len / sizeof(*buf); n++) {
                r = do_inject_vcpu(vcpu, &buf[n]);
                if (r)
                        break;
        }

out_unlock:
        spin_unlock(&li->lock);
out_free:
        vfree(buf);

        return r;
}

static void store_local_irq(struct kvm_s390_local_interrupt *li,
                            struct kvm_s390_irq *irq,
                            unsigned long irq_type)
{
        switch (irq_type) {
        case IRQ_PEND_MCHK_EX:
        case IRQ_PEND_MCHK_REP:
                irq->type = KVM_S390_MCHK;
                irq->u.mchk = li->irq.mchk;
                break;
        case IRQ_PEND_PROG:
                irq->type = KVM_S390_PROGRAM_INT;
                irq->u.pgm = li->irq.pgm;
                break;
        case IRQ_PEND_PFAULT_INIT:
                irq->type = KVM_S390_INT_PFAULT_INIT;
                irq->u.ext = li->irq.ext;
                break;
        case IRQ_PEND_EXT_EXTERNAL:
                irq->type = KVM_S390_INT_EXTERNAL_CALL;
                irq->u.extcall = li->irq.extcall;
                break;
        case IRQ_PEND_EXT_CLOCK_COMP:
                irq->type = KVM_S390_INT_CLOCK_COMP;
                break;
        case IRQ_PEND_EXT_CPU_TIMER:
                irq->type = KVM_S390_INT_CPU_TIMER;
                break;
        case IRQ_PEND_SIGP_STOP:
                irq->type = KVM_S390_SIGP_STOP;
                irq->u.stop = li->irq.stop;
                break;
        case IRQ_PEND_RESTART:
                irq->type = KVM_S390_RESTART;
                break;
        case IRQ_PEND_SET_PREFIX:
                irq->type = KVM_S390_SIGP_SET_PREFIX;
                irq->u.prefix = li->irq.prefix;
                break;
        }
}

int kvm_s390_get_irq_state(struct kvm_vcpu *vcpu, __u8 __user *buf, int len)
{
        int scn;
        DECLARE_BITMAP(sigp_emerg_pending, KVM_MAX_VCPUS);
        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
        unsigned long pending_irqs;
        struct kvm_s390_irq irq;
        unsigned long irq_type;
        int cpuaddr;
        int n = 0;

        spin_lock(&li->lock);
        pending_irqs = li->pending_irqs;
        memcpy(&sigp_emerg_pending, &li->sigp_emerg_pending,
               sizeof(sigp_emerg_pending));
        spin_unlock(&li->lock);

        for_each_set_bit(irq_type, &pending_irqs, IRQ_PEND_COUNT) {
                memset(&irq, 0, sizeof(irq));
                if (irq_type == IRQ_PEND_EXT_EMERGENCY)
                        continue;
                if (n + sizeof(irq) > len)
                        return -ENOBUFS;
                store_local_irq(&vcpu->arch.local_int, &irq, irq_type);
                if (copy_to_user(&buf[n], &irq, sizeof(irq)))
                        return -EFAULT;
                n += sizeof(irq);
        }

        if (test_bit(IRQ_PEND_EXT_EMERGENCY, &pending_irqs)) {
                for_each_set_bit(cpuaddr, sigp_emerg_pending, KVM_MAX_VCPUS) {
                        memset(&irq, 0, sizeof(irq));
                        if (n + sizeof(irq) > len)
                                return -ENOBUFS;
                        irq.type = KVM_S390_INT_EMERGENCY;
                        irq.u.emerg.code = cpuaddr;
                        if (copy_to_user(&buf[n], &irq, sizeof(irq)))
                                return -EFAULT;
                        n += sizeof(irq);
                }
        }

        if (sca_ext_call_pending(vcpu, &scn)) {
                if (n + sizeof(irq) > len)
                        return -ENOBUFS;
                memset(&irq, 0, sizeof(irq));
                irq.type = KVM_S390_INT_EXTERNAL_CALL;
                irq.u.extcall.code = scn;
                if (copy_to_user(&buf[n], &irq, sizeof(irq)))
                        return -EFAULT;
                n += sizeof(irq);
        }

        return n;
}

static void __airqs_kick_single_vcpu(struct kvm *kvm, u8 deliverable_mask)
{
        int vcpu_idx, online_vcpus = atomic_read(&kvm->online_vcpus);
        struct kvm_s390_gisa_interrupt *gi = &kvm->arch.gisa_int;
        struct kvm_vcpu *vcpu;
        u8 vcpu_isc_mask;

        for_each_set_bit(vcpu_idx, kvm->arch.idle_mask, online_vcpus) {
                vcpu = kvm_get_vcpu(kvm, vcpu_idx);
                if (psw_ioint_disabled(vcpu))
                        continue;
                vcpu_isc_mask = (u8)(vcpu->arch.sie_block->gcr[6] >> 24);
                if (deliverable_mask & vcpu_isc_mask) {
                        /* lately kicked but not yet running */
                        if (test_and_set_bit(vcpu_idx, gi->kicked_mask))
                                return;
                        kvm_s390_vcpu_wakeup(vcpu);
                        return;
                }
        }
}

static enum hrtimer_restart gisa_vcpu_kicker(struct hrtimer *timer)
{
        struct kvm_s390_gisa_interrupt *gi =
                container_of(timer, struct kvm_s390_gisa_interrupt, timer);
        struct kvm *kvm =
                container_of(gi->origin, struct sie_page2, gisa)->kvm;
        u8 pending_mask;

        pending_mask = gisa_get_ipm_or_restore_iam(gi);
        if (pending_mask) {
                __airqs_kick_single_vcpu(kvm, pending_mask);
                hrtimer_forward_now(timer, ns_to_ktime(gi->expires));
                return HRTIMER_RESTART;
        }

        return HRTIMER_NORESTART;
}

#define NULL_GISA_ADDR 0x00000000UL
#define NONE_GISA_ADDR 0x00000001UL
#define GISA_ADDR_MASK 0xfffff000UL

static void process_gib_alert_list(void)
{
        struct kvm_s390_gisa_interrupt *gi;
        u32 final, gisa_phys, origin = 0UL;
        struct kvm_s390_gisa *gisa;
        struct kvm *kvm;

        do {
                /*
                 * If the NONE_GISA_ADDR is still stored in the alert list
                 * origin, we will leave the outer loop. No further GISA has
                 * been added to the alert list by millicode while processing
                 * the current alert list.
                 */
                final = (origin & NONE_GISA_ADDR);
                /*
                 * Cut off the alert list and store the NONE_GISA_ADDR in the
                 * alert list origin to avoid further GAL interruptions.
                 * A new alert list can be build up by millicode in parallel
                 * for guests not in the yet cut-off alert list. When in the
                 * final loop, store the NULL_GISA_ADDR instead. This will re-
                 * enable GAL interruptions on the host again.
                 */
                origin = xchg(&gib->alert_list_origin,
                              (!final) ? NONE_GISA_ADDR : NULL_GISA_ADDR);
                /*
                 * Loop through the just cut-off alert list and start the
                 * gisa timers to kick idle vcpus to consume the pending
                 * interruptions asap.
                 */
                while (origin & GISA_ADDR_MASK) {
                        gisa_phys = origin;
                        gisa = phys_to_virt(gisa_phys);
                        origin = gisa->next_alert;
                        gisa->next_alert = gisa_phys;
                        kvm = container_of(gisa, struct sie_page2, gisa)->kvm;
                        gi = &kvm->arch.gisa_int;
                        if (hrtimer_active(&gi->timer))
                                hrtimer_cancel(&gi->timer);
                        hrtimer_start(&gi->timer, 0, HRTIMER_MODE_REL);
                }
        } while (!final);

}

void kvm_s390_gisa_clear(struct kvm *kvm)
{
        struct kvm_s390_gisa_interrupt *gi = &kvm->arch.gisa_int;

        if (!gi->origin)
                return;
        gisa_clear_ipm(gi->origin);
        VM_EVENT(kvm, 3, "gisa 0x%p cleared", gi->origin);
}

void kvm_s390_gisa_init(struct kvm *kvm)
{
        struct kvm_s390_gisa_interrupt *gi = &kvm->arch.gisa_int;

        if (!css_general_characteristics.aiv)
                return;
        gi->origin = &kvm->arch.sie_page2->gisa;
        gi->alert.mask = 0;
        spin_lock_init(&gi->alert.ref_lock);
        gi->expires = 50 * 1000; /* 50 usec */
        hrtimer_setup(&gi->timer, gisa_vcpu_kicker, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
        memset(gi->origin, 0, sizeof(struct kvm_s390_gisa));
        gi->origin->next_alert = (u32)virt_to_phys(gi->origin);
        VM_EVENT(kvm, 3, "gisa 0x%p initialized", gi->origin);
}

void kvm_s390_gisa_enable(struct kvm *kvm)
{
        struct kvm_s390_gisa_interrupt *gi = &kvm->arch.gisa_int;
        struct kvm_vcpu *vcpu;
        unsigned long i;
        u32 gisa_desc;

        if (gi->origin)
                return;
        kvm_s390_gisa_init(kvm);
        gisa_desc = kvm_s390_get_gisa_desc(kvm);
        if (!gisa_desc)
                return;
        kvm_for_each_vcpu(i, vcpu, kvm) {
                mutex_lock(&vcpu->mutex);
                vcpu->arch.sie_block->gd = gisa_desc;
                vcpu->arch.sie_block->eca |= ECA_AIV;
                VCPU_EVENT(vcpu, 3, "AIV gisa format-%u enabled for cpu %03u",
                           vcpu->arch.sie_block->gd & 0x3, vcpu->vcpu_id);
                mutex_unlock(&vcpu->mutex);
        }
}

void kvm_s390_gisa_destroy(struct kvm *kvm)
{
        struct kvm_s390_gisa_interrupt *gi = &kvm->arch.gisa_int;
        struct kvm_s390_gisa *gisa = gi->origin;

        if (!gi->origin)
                return;
        WARN(gi->alert.mask != 0x00,
             "unexpected non zero alert.mask 0x%02x",
             gi->alert.mask);
        gi->alert.mask = 0x00;
        if (gisa_set_iam(gi->origin, gi->alert.mask))
                process_gib_alert_list();
        hrtimer_cancel(&gi->timer);
        gi->origin = NULL;
        VM_EVENT(kvm, 3, "gisa 0x%p destroyed", gisa);
}

void kvm_s390_gisa_disable(struct kvm *kvm)
{
        struct kvm_s390_gisa_interrupt *gi = &kvm->arch.gisa_int;
        struct kvm_vcpu *vcpu;
        unsigned long i;

        if (!gi->origin)
                return;
        kvm_for_each_vcpu(i, vcpu, kvm) {
                mutex_lock(&vcpu->mutex);
                vcpu->arch.sie_block->eca &= ~ECA_AIV;
                vcpu->arch.sie_block->gd = 0U;
                mutex_unlock(&vcpu->mutex);
                VCPU_EVENT(vcpu, 3, "AIV disabled for cpu %03u", vcpu->vcpu_id);
        }
        kvm_s390_gisa_destroy(kvm);
}

/**
 * kvm_s390_gisc_register - register a guest ISC
 *
 * @kvm:  the kernel vm to work with
 * @gisc: the guest interruption sub class to register
 *
 * The function extends the vm specific alert mask to use.
 * The effective IAM mask in the GISA is updated as well
 * in case the GISA is not part of the GIB alert list.
 * It will be updated latest when the IAM gets restored
 * by gisa_get_ipm_or_restore_iam().
 *
 * Returns: the nonspecific ISC (NISC) the gib alert mechanism
 *          has registered with the channel subsystem.
 *          -ENODEV in case the vm uses no GISA
 *          -ERANGE in case the guest ISC is invalid
 */
int kvm_s390_gisc_register(struct kvm *kvm, u32 gisc)
{
        struct kvm_s390_gisa_interrupt *gi = &kvm->arch.gisa_int;

        if (!gi->origin)
                return -ENODEV;
        if (gisc > MAX_ISC)
                return -ERANGE;

        spin_lock(&gi->alert.ref_lock);
        gi->alert.ref_count[gisc]++;
        if (gi->alert.ref_count[gisc] == 1) {
                gi->alert.mask |= 0x80 >> gisc;
                gisa_set_iam(gi->origin, gi->alert.mask);
        }
        spin_unlock(&gi->alert.ref_lock);

        return gib->nisc;
}
EXPORT_SYMBOL_GPL(kvm_s390_gisc_register);

/**
 * kvm_s390_gisc_unregister - unregister a guest ISC
 *
 * @kvm:  the kernel vm to work with
 * @gisc: the guest interruption sub class to register
 *
 * The function reduces the vm specific alert mask to use.
 * The effective IAM mask in the GISA is updated as well
 * in case the GISA is not part of the GIB alert list.
 * It will be updated latest when the IAM gets restored
 * by gisa_get_ipm_or_restore_iam().
 *
 * Returns: the nonspecific ISC (NISC) the gib alert mechanism
 *          has registered with the channel subsystem.
 *          -ENODEV in case the vm uses no GISA
 *          -ERANGE in case the guest ISC is invalid
 *          -EINVAL in case the guest ISC is not registered
 */
int kvm_s390_gisc_unregister(struct kvm *kvm, u32 gisc)
{
        struct kvm_s390_gisa_interrupt *gi = &kvm->arch.gisa_int;
        int rc = 0;

        if (!gi->origin)
                return -ENODEV;
        if (gisc > MAX_ISC)
                return -ERANGE;

        spin_lock(&gi->alert.ref_lock);
        if (gi->alert.ref_count[gisc] == 0) {
                rc = -EINVAL;
                goto out;
        }
        gi->alert.ref_count[gisc]--;
        if (gi->alert.ref_count[gisc] == 0) {
                gi->alert.mask &= ~(0x80 >> gisc);
                gisa_set_iam(gi->origin, gi->alert.mask);
        }
out:
        spin_unlock(&gi->alert.ref_lock);

        return rc;
}
EXPORT_SYMBOL_GPL(kvm_s390_gisc_unregister);

static void aen_host_forward(unsigned long si)
{
        struct kvm_s390_gisa_interrupt *gi;
        struct zpci_gaite *gaite;
        struct kvm *kvm;

        gaite = (struct zpci_gaite *)aift->gait +
                (si * sizeof(struct zpci_gaite));
        if (gaite->count == 0)
                return;
        if (gaite->aisb != 0)
                set_bit_inv(gaite->aisbo, phys_to_virt(gaite->aisb));

        kvm = kvm_s390_pci_si_to_kvm(aift, si);
        if (!kvm)
                return;
        gi = &kvm->arch.gisa_int;

        if (!(gi->origin->g1.simm & AIS_MODE_MASK(gaite->gisc)) ||
            !(gi->origin->g1.nimm & AIS_MODE_MASK(gaite->gisc))) {
                gisa_set_ipm_gisc(gi->origin, gaite->gisc);
                if (hrtimer_active(&gi->timer))
                        hrtimer_cancel(&gi->timer);
                hrtimer_start(&gi->timer, 0, HRTIMER_MODE_REL);
                kvm->stat.aen_forward++;
        }
}

static void aen_process_gait(u8 isc)
{
        bool found = false, first = true;
        union zpci_sic_iib iib = {{0}};
        unsigned long si, flags;

        spin_lock_irqsave(&aift->gait_lock, flags);

        if (!aift->gait) {
                spin_unlock_irqrestore(&aift->gait_lock, flags);
                return;
        }

        for (si = 0;;) {
                /* Scan adapter summary indicator bit vector */
                si = airq_iv_scan(aift->sbv, si, airq_iv_end(aift->sbv));
                if (si == -1UL) {
                        if (first || found) {
                                /* Re-enable interrupts. */
                                zpci_set_irq_ctrl(SIC_IRQ_MODE_SINGLE, isc,
                                                  &iib);
                                first = found = false;
                        } else {
                                /* Interrupts on and all bits processed */
                                break;
                        }
                        found = false;
                        si = 0;
                        /* Scan again after re-enabling interrupts */
                        continue;
                }
                found = true;
                aen_host_forward(si);
        }

        spin_unlock_irqrestore(&aift->gait_lock, flags);
}

static void gib_alert_irq_handler(struct airq_struct *airq,
                                  struct tpi_info *tpi_info)
{
        struct tpi_adapter_info *info = (struct tpi_adapter_info *)tpi_info;

        inc_irq_stat(IRQIO_GAL);

        if ((info->forward || info->error) &&
            IS_ENABLED(CONFIG_VFIO_PCI_ZDEV_KVM)) {
                aen_process_gait(info->isc);
                if (info->aism != 0)
                        process_gib_alert_list();
        } else {
                process_gib_alert_list();
        }
}

static struct airq_struct gib_alert_irq = {
        .handler = gib_alert_irq_handler,
};

void kvm_s390_gib_destroy(void)
{
        if (!gib)
                return;
        if (kvm_s390_pci_interp_allowed() && aift) {
                mutex_lock(&aift->aift_lock);
                kvm_s390_pci_aen_exit();
                mutex_unlock(&aift->aift_lock);
        }
        chsc_sgib(0);
        unregister_adapter_interrupt(&gib_alert_irq);
        free_page((unsigned long)gib);
        gib = NULL;
}

int __init kvm_s390_gib_init(u8 nisc)
{
        u32 gib_origin;
        int rc = 0;

        if (!css_general_characteristics.aiv) {
                KVM_EVENT(3, "%s", "gib not initialized, no AIV facility");
                goto out;
        }

        gib = (struct kvm_s390_gib *)get_zeroed_page(GFP_KERNEL_ACCOUNT | GFP_DMA);
        if (!gib) {
                rc = -ENOMEM;
                goto out;
        }

        gib_alert_irq.isc = nisc;
        if (register_adapter_interrupt(&gib_alert_irq)) {
                pr_err("Registering the GIB alert interruption handler failed\n");
                rc = -EIO;
                goto out_free_gib;
        }
        /* adapter interrupts used for AP (applicable here) don't use the LSI */
        *gib_alert_irq.lsi_ptr = 0xff;

        gib->nisc = nisc;
        gib_origin = virt_to_phys(gib);
        if (chsc_sgib(gib_origin)) {
                pr_err("Associating the GIB with the AIV facility failed\n");
                free_page((unsigned long)gib);
                gib = NULL;
                rc = -EIO;
                goto out_unreg_gal;
        }

        if (kvm_s390_pci_interp_allowed()) {
                if (kvm_s390_pci_aen_init(nisc)) {
                        pr_err("Initializing AEN for PCI failed\n");
                        rc = -EIO;
                        goto out_unreg_gal;
                }
        }

        KVM_EVENT(3, "gib 0x%p (nisc=%d) initialized", gib, gib->nisc);
        goto out;

out_unreg_gal:
        unregister_adapter_interrupt(&gib_alert_irq);
out_free_gib:
        free_page((unsigned long)gib);
        gib = NULL;
out:
        return rc;
}