// SPDX-License-Identifier: GPL-2.0
/*
 * handling privileged instructions
 *
 * Copyright IBM Corp. 2008, 2020
 *
 *    Author(s): Carsten Otte <cotte@de.ibm.com>
 *               Christian Borntraeger <borntraeger@de.ibm.com>
 */

#include <linux/kvm.h>
#include <linux/gfp.h>
#include <linux/errno.h>
#include <linux/mm_types.h>
#include <linux/pgtable.h>
#include <linux/io.h>
#include <asm/asm-offsets.h>
#include <asm/facility.h>
#include <asm/current.h>
#include <asm/debug.h>
#include <asm/ebcdic.h>
#include <asm/sysinfo.h>
#include <asm/page-states.h>
#include <asm/ptrace.h>
#include <asm/sclp.h>
#include <asm/ap.h>
#include <asm/gmap_helpers.h>
#include "gaccess.h"
#include "kvm-s390.h"
#include "trace.h"
#include "gmap.h"

static int handle_ri(struct kvm_vcpu *vcpu)
{
        vcpu->stat.instruction_ri++;

        if (test_kvm_facility(vcpu->kvm, 64)) {
                VCPU_EVENT(vcpu, 3, "%s", "ENABLE: RI (lazy)");
                vcpu->arch.sie_block->ecb3 |= ECB3_RI;
                kvm_s390_retry_instr(vcpu);
                return 0;
        } else
                return kvm_s390_inject_program_int(vcpu, PGM_OPERATION);
}

int kvm_s390_handle_aa(struct kvm_vcpu *vcpu)
{
        if ((vcpu->arch.sie_block->ipa & 0xf) <= 4)
                return handle_ri(vcpu);
        else
                return -EOPNOTSUPP;
}

static int handle_gs(struct kvm_vcpu *vcpu)
{
        vcpu->stat.instruction_gs++;

        if (test_kvm_facility(vcpu->kvm, 133)) {
                VCPU_EVENT(vcpu, 3, "%s", "ENABLE: GS (lazy)");
                preempt_disable();
                local_ctl_set_bit(2, CR2_GUARDED_STORAGE_BIT);
                current->thread.gs_cb = (struct gs_cb *)&vcpu->run->s.regs.gscb;
                restore_gs_cb(current->thread.gs_cb);
                preempt_enable();
                vcpu->arch.sie_block->ecb |= ECB_GS;
                vcpu->arch.sie_block->ecd |= ECD_HOSTREGMGMT;
                vcpu->arch.gs_enabled = 1;
                kvm_s390_retry_instr(vcpu);
                return 0;
        } else
                return kvm_s390_inject_program_int(vcpu, PGM_OPERATION);
}

int kvm_s390_handle_e3(struct kvm_vcpu *vcpu)
{
        int code = vcpu->arch.sie_block->ipb & 0xff;

        if (code == 0x49 || code == 0x4d)
                return handle_gs(vcpu);
        else
                return -EOPNOTSUPP;
}
/* Handle SCK (SET CLOCK) interception */
static int handle_set_clock(struct kvm_vcpu *vcpu)
{
        struct kvm_s390_vm_tod_clock gtod = { 0 };
        int rc;
        u8 ar;
        u64 op2;

        vcpu->stat.instruction_sck++;

        if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
                return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);

        op2 = kvm_s390_get_base_disp_s(vcpu, &ar);
        if (op2 & 7)    /* Operand must be on a doubleword boundary */
                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
        rc = read_guest(vcpu, op2, ar, &gtod.tod, sizeof(gtod.tod));
        if (rc)
                return kvm_s390_inject_prog_cond(vcpu, rc);

        VCPU_EVENT(vcpu, 3, "SCK: setting guest TOD to 0x%llx", gtod.tod);
        /*
         * To set the TOD clock the kvm lock must be taken, but the vcpu lock
         * is already held in handle_set_clock. The usual lock order is the
         * opposite.  As SCK is deprecated and should not be used in several
         * cases, for example when the multiple epoch facility or TOD clock
         * steering facility is installed (see Principles of Operation),  a
         * slow path can be used.  If the lock can not be taken via try_lock,
         * the instruction will be retried via -EAGAIN at a later point in
         * time.
         */
        if (!kvm_s390_try_set_tod_clock(vcpu->kvm, &gtod)) {
                kvm_s390_retry_instr(vcpu);
                return -EAGAIN;
        }

        kvm_s390_set_psw_cc(vcpu, 0);
        return 0;
}

static int handle_set_prefix(struct kvm_vcpu *vcpu)
{
        u64 operand2;
        u32 address;
        int rc;
        u8 ar;

        vcpu->stat.instruction_spx++;

        if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
                return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);

        operand2 = kvm_s390_get_base_disp_s(vcpu, &ar);

        /* must be word boundary */
        if (operand2 & 3)
                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);

        /* get the value */
        rc = read_guest(vcpu, operand2, ar, &address, sizeof(address));
        if (rc)
                return kvm_s390_inject_prog_cond(vcpu, rc);

        address &= 0x7fffe000u;

        /*
         * Make sure the new value is valid memory. We only need to check the
         * first page, since address is 8k aligned and memory pieces are always
         * at least 1MB aligned and have at least a size of 1MB.
         */
        if (!kvm_is_gpa_in_memslot(vcpu->kvm, address))
                return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);

        kvm_s390_set_prefix(vcpu, address);
        trace_kvm_s390_handle_prefix(vcpu, 1, address);
        return 0;
}

static int handle_store_prefix(struct kvm_vcpu *vcpu)
{
        u64 operand2;
        u32 address;
        int rc;
        u8 ar;

        vcpu->stat.instruction_stpx++;

        if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
                return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);

        operand2 = kvm_s390_get_base_disp_s(vcpu, &ar);

        /* must be word boundary */
        if (operand2 & 3)
                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);

        address = kvm_s390_get_prefix(vcpu);

        /* get the value */
        rc = write_guest(vcpu, operand2, ar, &address, sizeof(address));
        if (rc)
                return kvm_s390_inject_prog_cond(vcpu, rc);

        VCPU_EVENT(vcpu, 3, "STPX: storing prefix 0x%x into 0x%llx", address, operand2);
        trace_kvm_s390_handle_prefix(vcpu, 0, address);
        return 0;
}

static int handle_store_cpu_address(struct kvm_vcpu *vcpu)
{
        u16 vcpu_id = vcpu->vcpu_id;
        u64 ga;
        int rc;
        u8 ar;

        vcpu->stat.instruction_stap++;

        if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
                return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);

        ga = kvm_s390_get_base_disp_s(vcpu, &ar);

        if (ga & 1)
                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);

        rc = write_guest(vcpu, ga, ar, &vcpu_id, sizeof(vcpu_id));
        if (rc)
                return kvm_s390_inject_prog_cond(vcpu, rc);

        VCPU_EVENT(vcpu, 3, "STAP: storing cpu address (%u) to 0x%llx", vcpu_id, ga);
        trace_kvm_s390_handle_stap(vcpu, ga);
        return 0;
}

int kvm_s390_skey_check_enable(struct kvm_vcpu *vcpu)
{
        int rc;

        trace_kvm_s390_skey_related_inst(vcpu);
        /* Already enabled? */
        if (vcpu->arch.skey_enabled)
                return 0;

        rc = gmap_enable_skeys(vcpu->arch.gmap);
        VCPU_EVENT(vcpu, 3, "enabling storage keys for guest: %d", rc);
        if (rc)
                return rc;

        if (kvm_s390_test_cpuflags(vcpu, CPUSTAT_KSS))
                kvm_s390_clear_cpuflags(vcpu, CPUSTAT_KSS);
        if (!vcpu->kvm->arch.use_skf)
                vcpu->arch.sie_block->ictl |= ICTL_ISKE | ICTL_SSKE | ICTL_RRBE;
        else
                vcpu->arch.sie_block->ictl &= ~(ICTL_ISKE | ICTL_SSKE | ICTL_RRBE);
        vcpu->arch.skey_enabled = true;
        return 0;
}

static int try_handle_skey(struct kvm_vcpu *vcpu)
{
        int rc;

        rc = kvm_s390_skey_check_enable(vcpu);
        if (rc)
                return rc;
        if (vcpu->kvm->arch.use_skf) {
                /* with storage-key facility, SIE interprets it for us */
                kvm_s390_retry_instr(vcpu);
                VCPU_EVENT(vcpu, 4, "%s", "retrying storage key operation");
                return -EAGAIN;
        }
        return 0;
}

static int handle_iske(struct kvm_vcpu *vcpu)
{
        unsigned long gaddr;
        int reg1, reg2;
        union skey key;
        int rc;

        vcpu->stat.instruction_iske++;

        if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
                return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);

        rc = try_handle_skey(vcpu);
        if (rc)
                return rc != -EAGAIN ? rc : 0;

        kvm_s390_get_regs_rre(vcpu, &reg1, &reg2);

        gaddr = vcpu->run->s.regs.gprs[reg2] & PAGE_MASK;
        gaddr = kvm_s390_logical_to_effective(vcpu, gaddr);
        gaddr = kvm_s390_real_to_abs(vcpu, gaddr);
        scoped_guard(read_lock, &vcpu->kvm->mmu_lock)
                rc = dat_get_storage_key(vcpu->arch.gmap->asce, gpa_to_gfn(gaddr), &key);
        if (rc > 0)
                return kvm_s390_inject_program_int(vcpu, rc);
        if (rc < 0)
                return rc;
        vcpu->run->s.regs.gprs[reg1] &= ~0xff;
        vcpu->run->s.regs.gprs[reg1] |= key.skey;
        return 0;
}

static int handle_rrbe(struct kvm_vcpu *vcpu)
{
        unsigned long gaddr;
        int reg1, reg2;
        int rc;

        vcpu->stat.instruction_rrbe++;

        if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
                return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);

        rc = try_handle_skey(vcpu);
        if (rc)
                return rc != -EAGAIN ? rc : 0;

        kvm_s390_get_regs_rre(vcpu, &reg1, &reg2);

        gaddr = vcpu->run->s.regs.gprs[reg2] & PAGE_MASK;
        gaddr = kvm_s390_logical_to_effective(vcpu, gaddr);
        gaddr = kvm_s390_real_to_abs(vcpu, gaddr);
        scoped_guard(read_lock, &vcpu->kvm->mmu_lock)
                rc = dat_reset_reference_bit(vcpu->arch.gmap->asce, gpa_to_gfn(gaddr));
        if (rc > 0)
                return kvm_s390_inject_program_int(vcpu, rc);
        if (rc < 0)
                return rc;
        kvm_s390_set_psw_cc(vcpu, rc);
        return 0;
}

#define SSKE_NQ 0x8
#define SSKE_MR 0x4
#define SSKE_MC 0x2
#define SSKE_MB 0x1
static int handle_sske(struct kvm_vcpu *vcpu)
{
        unsigned char m3 = vcpu->arch.sie_block->ipb >> 28;
        unsigned long start, end;
        union skey key, oldkey;
        int reg1, reg2;
        int rc;

        vcpu->stat.instruction_sske++;

        if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
                return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);

        rc = try_handle_skey(vcpu);
        if (rc)
                return rc != -EAGAIN ? rc : 0;

        if (!test_kvm_facility(vcpu->kvm, 8))
                m3 &= ~SSKE_MB;
        if (!test_kvm_facility(vcpu->kvm, 10))
                m3 &= ~(SSKE_MC | SSKE_MR);
        if (!test_kvm_facility(vcpu->kvm, 14))
                m3 &= ~SSKE_NQ;

        kvm_s390_get_regs_rre(vcpu, &reg1, &reg2);

        key.skey = vcpu->run->s.regs.gprs[reg1] & 0xfe;
        start = vcpu->run->s.regs.gprs[reg2] & PAGE_MASK;
        start = kvm_s390_logical_to_effective(vcpu, start);
        if (m3 & SSKE_MB) {
                /* start already designates an absolute address */
                end = (start + _SEGMENT_SIZE) & ~(_SEGMENT_SIZE - 1);
        } else {
                start = kvm_s390_real_to_abs(vcpu, start);
                end = start + PAGE_SIZE;
        }

        while (start != end) {
                scoped_guard(read_lock, &vcpu->kvm->mmu_lock) {
                        rc = dat_cond_set_storage_key(vcpu->arch.mc, vcpu->arch.gmap->asce,
                                                      gpa_to_gfn(start), key, &oldkey,
                                                      m3 & SSKE_NQ, m3 & SSKE_MR, m3 & SSKE_MC);
                }
                if (rc > 1)
                        return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
                if (rc == -ENOMEM) {
                        kvm_s390_mmu_cache_topup(vcpu->arch.mc);
                        continue;
                }
                if (rc < 0)
                        return rc;
                start += PAGE_SIZE;
        }

        if (m3 & (SSKE_MC | SSKE_MR)) {
                if (m3 & SSKE_MB) {
                        /* skey in reg1 is unpredictable */
                        kvm_s390_set_psw_cc(vcpu, 3);
                } else {
                        kvm_s390_set_psw_cc(vcpu, rc);
                        vcpu->run->s.regs.gprs[reg1] &= ~0xff00UL;
                        vcpu->run->s.regs.gprs[reg1] |= (u64)oldkey.skey << 8;
                }
        }
        if (m3 & SSKE_MB) {
                if (psw_bits(vcpu->arch.sie_block->gpsw).eaba == PSW_BITS_AMODE_64BIT)
                        vcpu->run->s.regs.gprs[reg2] &= ~PAGE_MASK;
                else
                        vcpu->run->s.regs.gprs[reg2] &= ~0xfffff000UL;
                end = kvm_s390_logical_to_effective(vcpu, end);
                vcpu->run->s.regs.gprs[reg2] |= end;
        }
        return 0;
}

static int handle_ipte_interlock(struct kvm_vcpu *vcpu)
{
        vcpu->stat.instruction_ipte_interlock++;
        if (psw_bits(vcpu->arch.sie_block->gpsw).pstate)
                return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);
        wait_event(vcpu->kvm->arch.ipte_wq, !ipte_lock_held(vcpu->kvm));
        kvm_s390_retry_instr(vcpu);
        VCPU_EVENT(vcpu, 4, "%s", "retrying ipte interlock operation");
        return 0;
}

static int handle_test_block(struct kvm_vcpu *vcpu)
{
        gpa_t addr;
        int reg2;

        vcpu->stat.instruction_tb++;

        if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
                return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);

        kvm_s390_get_regs_rre(vcpu, NULL, &reg2);
        addr = vcpu->run->s.regs.gprs[reg2] & PAGE_MASK;
        addr = kvm_s390_logical_to_effective(vcpu, addr);
        if (kvm_s390_check_low_addr_prot_real(vcpu, addr))
                return kvm_s390_inject_prog_irq(vcpu, &vcpu->arch.pgm);
        addr = kvm_s390_real_to_abs(vcpu, addr);

        if (!kvm_is_gpa_in_memslot(vcpu->kvm, addr))
                return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
        /*
         * We don't expect errors on modern systems, and do not care
         * about storage keys (yet), so let's just clear the page.
         */
        if (kvm_clear_guest(vcpu->kvm, addr, PAGE_SIZE))
                return -EFAULT;
        kvm_s390_set_psw_cc(vcpu, 0);
        vcpu->run->s.regs.gprs[0] = 0;
        return 0;
}

static int handle_tpi(struct kvm_vcpu *vcpu)
{
        struct kvm_s390_interrupt_info *inti;
        unsigned long len;
        u32 tpi_data[3];
        int rc;
        u64 addr;
        u8 ar;

        vcpu->stat.instruction_tpi++;

        addr = kvm_s390_get_base_disp_s(vcpu, &ar);
        if (addr & 3)
                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);

        inti = kvm_s390_get_io_int(vcpu->kvm, vcpu->arch.sie_block->gcr[6], 0);
        if (!inti) {
                kvm_s390_set_psw_cc(vcpu, 0);
                return 0;
        }

        tpi_data[0] = inti->io.subchannel_id << 16 | inti->io.subchannel_nr;
        tpi_data[1] = inti->io.io_int_parm;
        tpi_data[2] = inti->io.io_int_word;
        if (addr) {
                /*
                 * Store the two-word I/O interruption code into the
                 * provided area.
                 */
                len = sizeof(tpi_data) - 4;
                rc = write_guest(vcpu, addr, ar, &tpi_data, len);
                if (rc) {
                        rc = kvm_s390_inject_prog_cond(vcpu, rc);
                        goto reinject_interrupt;
                }
        } else {
                /*
                 * Store the three-word I/O interruption code into
                 * the appropriate lowcore area.
                 */
                len = sizeof(tpi_data);
                if (write_guest_lc(vcpu, __LC_SUBCHANNEL_ID, &tpi_data, len)) {
                        /* failed writes to the low core are not recoverable */
                        rc = -EFAULT;
                        goto reinject_interrupt;
                }
        }

        /* irq was successfully handed to the guest */
        kfree(inti);
        kvm_s390_set_psw_cc(vcpu, 1);
        return 0;
reinject_interrupt:
        /*
         * If we encounter a problem storing the interruption code, the
         * instruction is suppressed from the guest's view: reinject the
         * interrupt.
         */
        if (kvm_s390_reinject_io_int(vcpu->kvm, inti)) {
                kfree(inti);
                rc = -EFAULT;
        }
        /* don't set the cc, a pgm irq was injected or we drop to user space */
        return rc ? -EFAULT : 0;
}

static int handle_tsch(struct kvm_vcpu *vcpu)
{
        struct kvm_s390_interrupt_info *inti = NULL;
        const u64 isc_mask = 0xffUL << 24; /* all iscs set */

        vcpu->stat.instruction_tsch++;

        /* a valid schid has at least one bit set */
        if (vcpu->run->s.regs.gprs[1])
                inti = kvm_s390_get_io_int(vcpu->kvm, isc_mask,
                                           vcpu->run->s.regs.gprs[1]);

        /*
         * Prepare exit to userspace.
         * We indicate whether we dequeued a pending I/O interrupt
         * so that userspace can re-inject it if the instruction gets
         * a program check. While this may re-order the pending I/O
         * interrupts, this is no problem since the priority is kept
         * intact.
         */
        vcpu->run->exit_reason = KVM_EXIT_S390_TSCH;
        vcpu->run->s390_tsch.dequeued = !!inti;
        if (inti) {
                vcpu->run->s390_tsch.subchannel_id = inti->io.subchannel_id;
                vcpu->run->s390_tsch.subchannel_nr = inti->io.subchannel_nr;
                vcpu->run->s390_tsch.io_int_parm = inti->io.io_int_parm;
                vcpu->run->s390_tsch.io_int_word = inti->io.io_int_word;
        }
        vcpu->run->s390_tsch.ipb = vcpu->arch.sie_block->ipb;
        kfree(inti);
        return -EREMOTE;
}

static int handle_io_inst(struct kvm_vcpu *vcpu)
{
        VCPU_EVENT(vcpu, 4, "%s", "I/O instruction");

        if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
                return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);

        if (vcpu->kvm->arch.css_support) {
                /*
                 * Most I/O instructions will be handled by userspace.
                 * Exceptions are tpi and the interrupt portion of tsch.
                 */
                if (vcpu->arch.sie_block->ipa == 0xb236)
                        return handle_tpi(vcpu);
                if (vcpu->arch.sie_block->ipa == 0xb235)
                        return handle_tsch(vcpu);
                /* Handle in userspace. */
                vcpu->stat.instruction_io_other++;
                return -EOPNOTSUPP;
        } else {
                /*
                 * Set condition code 3 to stop the guest from issuing channel
                 * I/O instructions.
                 */
                kvm_s390_set_psw_cc(vcpu, 3);
                return 0;
        }
}

#if IS_ENABLED(CONFIG_VFIO_AP)
bool kvm_s390_is_gpa_in_memslot(struct kvm *kvm, gpa_t gpa)
{
        return kvm_is_gpa_in_memslot(kvm, gpa);
}
EXPORT_SYMBOL_FOR_MODULES(kvm_s390_is_gpa_in_memslot, "vfio_ap");
#endif

/*
 * handle_pqap: Handling pqap interception
 * @vcpu: the vcpu having issue the pqap instruction
 *
 * We now support PQAP/AQIC instructions and we need to correctly
 * answer the guest even if no dedicated driver's hook is available.
 *
 * The intercepting code calls a dedicated callback for this instruction
 * if a driver did register one in the CRYPTO satellite of the
 * SIE block.
 *
 * If no callback is available, the queues are not available, return this
 * response code to the caller and set CC to 3.
 * Else return the response code returned by the callback.
 */
static int handle_pqap(struct kvm_vcpu *vcpu)
{
        struct ap_queue_status status = {};
        crypto_hook pqap_hook;
        unsigned long reg0;
        int ret;
        uint8_t fc;

        /* Verify that the AP instruction are available */
        if (!ap_instructions_available())
                return -EOPNOTSUPP;
        /* Verify that the guest is allowed to use AP instructions */
        if (!(vcpu->arch.sie_block->eca & ECA_APIE))
                return -EOPNOTSUPP;
        /*
         * The only possibly intercepted functions when AP instructions are
         * available for the guest are AQIC and TAPQ with the t bit set
         * since we do not set IC.3 (FIII) we currently will only intercept
         * the AQIC function code.
         * Note: running nested under z/VM can result in intercepts for other
         * function codes, e.g. PQAP(QCI). We do not support this and bail out.
         */
        reg0 = vcpu->run->s.regs.gprs[0];
        fc = (reg0 >> 24) & 0xff;
        if (fc != 0x03)
                return -EOPNOTSUPP;

        /* PQAP instruction is allowed for guest kernel only */
        if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
                return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);

        /* Common PQAP instruction specification exceptions */
        /* bits 41-47 must all be zeros */
        if (reg0 & 0x007f0000UL)
                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
        /* APFT not install and T bit set */
        if (!test_kvm_facility(vcpu->kvm, 15) && (reg0 & 0x00800000UL))
                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
        /* APXA not installed and APID greater 64 or APQI greater 16 */
        if (!(vcpu->kvm->arch.crypto.crycbd & 0x02) && (reg0 & 0x0000c0f0UL))
                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);

        /* AQIC function code specific exception */
        /* facility 65 not present for AQIC function code */
        if (!test_kvm_facility(vcpu->kvm, 65))
                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);

        /*
         * If the hook callback is registered, there will be a pointer to the
         * hook function pointer in the kvm_s390_crypto structure. Lock the
         * owner, retrieve the hook function pointer and call the hook.
         */
        down_read(&vcpu->kvm->arch.crypto.pqap_hook_rwsem);
        if (vcpu->kvm->arch.crypto.pqap_hook) {
                pqap_hook = *vcpu->kvm->arch.crypto.pqap_hook;
                ret = pqap_hook(vcpu);
                if (!ret) {
                        if (vcpu->run->s.regs.gprs[1] & 0x00ff0000)
                                kvm_s390_set_psw_cc(vcpu, 3);
                        else
                                kvm_s390_set_psw_cc(vcpu, 0);
                }
                up_read(&vcpu->kvm->arch.crypto.pqap_hook_rwsem);
                return ret;
        }
        up_read(&vcpu->kvm->arch.crypto.pqap_hook_rwsem);
        /*
         * A vfio_driver must register a hook.
         * No hook means no driver to enable the SIE CRYCB and no queues.
         * We send this response to the guest.
         */
        status.response_code = 0x01;
        memcpy(&vcpu->run->s.regs.gprs[1], &status, sizeof(status));
        kvm_s390_set_psw_cc(vcpu, 3);
        return 0;
}

static int handle_stfl(struct kvm_vcpu *vcpu)
{
        int rc;
        unsigned int fac;

        vcpu->stat.instruction_stfl++;

        if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
                return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);

        /*
         * We need to shift the lower 32 facility bits (bit 0-31) from a u64
         * into a u32 memory representation. They will remain bits 0-31.
         */
        fac = *vcpu->kvm->arch.model.fac_list >> 32;
        rc = write_guest_lc(vcpu, offsetof(struct lowcore, stfl_fac_list),
                            &fac, sizeof(fac));
        if (rc)
                return rc;
        VCPU_EVENT(vcpu, 3, "STFL: store facility list 0x%x", fac);
        trace_kvm_s390_handle_stfl(vcpu, fac);
        return 0;
}

#define PSW_MASK_ADDR_MODE (PSW_MASK_EA | PSW_MASK_BA)
#define PSW_MASK_UNASSIGNED 0xb80800fe7fffffffUL
#define PSW_ADDR_24 0x0000000000ffffffUL
#define PSW_ADDR_31 0x000000007fffffffUL

int is_valid_psw(psw_t *psw)
{
        if (psw->mask & PSW_MASK_UNASSIGNED)
                return 0;
        if ((psw->mask & PSW_MASK_ADDR_MODE) == PSW_MASK_BA) {
                if (psw->addr & ~PSW_ADDR_31)
                        return 0;
        }
        if (!(psw->mask & PSW_MASK_ADDR_MODE) && (psw->addr & ~PSW_ADDR_24))
                return 0;
        if ((psw->mask & PSW_MASK_ADDR_MODE) ==  PSW_MASK_EA)
                return 0;
        if (psw->addr & 1)
                return 0;
        return 1;
}

int kvm_s390_handle_lpsw(struct kvm_vcpu *vcpu)
{
        psw_t *gpsw = &vcpu->arch.sie_block->gpsw;
        psw32_t new_psw;
        u64 addr;
        int rc;
        u8 ar;

        vcpu->stat.instruction_lpsw++;

        if (gpsw->mask & PSW_MASK_PSTATE)
                return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);

        addr = kvm_s390_get_base_disp_s(vcpu, &ar);
        if (addr & 7)
                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);

        rc = read_guest(vcpu, addr, ar, &new_psw, sizeof(new_psw));
        if (rc)
                return kvm_s390_inject_prog_cond(vcpu, rc);
        if (!(new_psw.mask & PSW32_MASK_BASE))
                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
        gpsw->mask = (new_psw.mask & ~PSW32_MASK_BASE) << 32;
        gpsw->mask |= new_psw.addr & PSW32_ADDR_AMODE;
        gpsw->addr = new_psw.addr & ~PSW32_ADDR_AMODE;
        if (!is_valid_psw(gpsw))
                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
        return 0;
}

static int handle_lpswe(struct kvm_vcpu *vcpu)
{
        psw_t new_psw;
        u64 addr;
        int rc;
        u8 ar;

        vcpu->stat.instruction_lpswe++;

        if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
                return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);

        addr = kvm_s390_get_base_disp_s(vcpu, &ar);
        if (addr & 7)
                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
        rc = read_guest(vcpu, addr, ar, &new_psw, sizeof(new_psw));
        if (rc)
                return kvm_s390_inject_prog_cond(vcpu, rc);
        vcpu->arch.sie_block->gpsw = new_psw;
        if (!is_valid_psw(&vcpu->arch.sie_block->gpsw))
                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
        return 0;
}

static int handle_lpswey(struct kvm_vcpu *vcpu)
{
        psw_t new_psw;
        u64 addr;
        int rc;
        u8 ar;

        vcpu->stat.instruction_lpswey++;

        if (!test_kvm_facility(vcpu->kvm, 193))
                return kvm_s390_inject_program_int(vcpu, PGM_OPERATION);

        if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
                return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);

        addr = kvm_s390_get_base_disp_siy(vcpu, &ar);
        if (addr & 7)
                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);

        rc = read_guest(vcpu, addr, ar, &new_psw, sizeof(new_psw));
        if (rc)
                return kvm_s390_inject_prog_cond(vcpu, rc);

        vcpu->arch.sie_block->gpsw = new_psw;
        if (!is_valid_psw(&vcpu->arch.sie_block->gpsw))
                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);

        return 0;
}

static int handle_stidp(struct kvm_vcpu *vcpu)
{
        u64 stidp_data = vcpu->kvm->arch.model.cpuid;
        u64 operand2;
        int rc;
        u8 ar;

        vcpu->stat.instruction_stidp++;

        if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
                return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);

        operand2 = kvm_s390_get_base_disp_s(vcpu, &ar);

        if (operand2 & 7)
                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);

        rc = write_guest(vcpu, operand2, ar, &stidp_data, sizeof(stidp_data));
        if (rc)
                return kvm_s390_inject_prog_cond(vcpu, rc);

        VCPU_EVENT(vcpu, 3, "STIDP: store cpu id 0x%llx", stidp_data);
        return 0;
}

static void handle_stsi_3_2_2(struct kvm_vcpu *vcpu, struct sysinfo_3_2_2 *mem)
{
        int cpus = 0;
        int n;

        cpus = atomic_read(&vcpu->kvm->online_vcpus);

        /* deal with other level 3 hypervisors */
        if (stsi(mem, 3, 2, 2))
                mem->count = 0;
        if (mem->count < 8)
                mem->count++;
        for (n = mem->count - 1; n > 0 ; n--)
                memcpy(&mem->vm[n], &mem->vm[n - 1], sizeof(mem->vm[0]));

        memset(&mem->vm[0], 0, sizeof(mem->vm[0]));
        mem->vm[0].cpus_total = cpus;
        mem->vm[0].cpus_configured = cpus;
        mem->vm[0].cpus_standby = 0;
        mem->vm[0].cpus_reserved = 0;
        mem->vm[0].caf = 1000;
        memcpy(mem->vm[0].name, "KVMguest", 8);
        ASCEBC(mem->vm[0].name, 8);
        memcpy(mem->vm[0].cpi, "KVM/Linux       ", 16);
        ASCEBC(mem->vm[0].cpi, 16);
}

static void insert_stsi_usr_data(struct kvm_vcpu *vcpu, u64 addr, u8 ar,
                                 u8 fc, u8 sel1, u16 sel2)
{
        vcpu->run->exit_reason = KVM_EXIT_S390_STSI;
        vcpu->run->s390_stsi.addr = addr;
        vcpu->run->s390_stsi.ar = ar;
        vcpu->run->s390_stsi.fc = fc;
        vcpu->run->s390_stsi.sel1 = sel1;
        vcpu->run->s390_stsi.sel2 = sel2;
}

static int handle_stsi(struct kvm_vcpu *vcpu)
{
        int fc = (vcpu->run->s.regs.gprs[0] & 0xf0000000) >> 28;
        int sel1 = vcpu->run->s.regs.gprs[0] & 0xff;
        int sel2 = vcpu->run->s.regs.gprs[1] & 0xffff;
        unsigned long mem = 0;
        u64 operand2;
        int rc = 0;
        u8 ar;

        vcpu->stat.instruction_stsi++;
        VCPU_EVENT(vcpu, 3, "STSI: fc: %u sel1: %u sel2: %u", fc, sel1, sel2);

        if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
                return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);

        /* Bailout forbidden function codes */
        if (fc > 3 && fc != 15)
                goto out_no_data;

        /*
         * fc 15 is provided only with
         *   - PTF/CPU topology support through facility 15
         *   - KVM_CAP_S390_USER_STSI
         */
        if (fc == 15 && (!test_kvm_facility(vcpu->kvm, 11) ||
                         !vcpu->kvm->arch.user_stsi))
                goto out_no_data;

        if (vcpu->run->s.regs.gprs[0] & 0x0fffff00
            || vcpu->run->s.regs.gprs[1] & 0xffff0000)
                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);

        if (fc == 0) {
                vcpu->run->s.regs.gprs[0] = 3 << 28;
                kvm_s390_set_psw_cc(vcpu, 0);
                return 0;
        }

        operand2 = kvm_s390_get_base_disp_s(vcpu, &ar);

        if (!kvm_s390_pv_cpu_is_protected(vcpu) && (operand2 & 0xfff))
                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);

        switch (fc) {
        case 1: /* same handling for 1 and 2 */
        case 2:
                mem = get_zeroed_page(GFP_KERNEL_ACCOUNT);
                if (!mem)
                        goto out_no_data;
                if (stsi((void *) mem, fc, sel1, sel2))
                        goto out_no_data;
                break;
        case 3:
                if (sel1 != 2 || sel2 != 2)
                        goto out_no_data;
                mem = get_zeroed_page(GFP_KERNEL_ACCOUNT);
                if (!mem)
                        goto out_no_data;
                handle_stsi_3_2_2(vcpu, (void *) mem);
                break;
        case 15: /* fc 15 is fully handled in userspace */
                insert_stsi_usr_data(vcpu, operand2, ar, fc, sel1, sel2);
                trace_kvm_s390_handle_stsi(vcpu, fc, sel1, sel2, operand2);
                return -EREMOTE;
        }
        if (kvm_s390_pv_cpu_is_protected(vcpu)) {
                memcpy(sida_addr(vcpu->arch.sie_block), (void *)mem, PAGE_SIZE);
                rc = 0;
        } else {
                rc = write_guest(vcpu, operand2, ar, (void *)mem, PAGE_SIZE);
        }
        if (rc) {
                rc = kvm_s390_inject_prog_cond(vcpu, rc);
                goto out;
        }
        if (vcpu->kvm->arch.user_stsi) {
                insert_stsi_usr_data(vcpu, operand2, ar, fc, sel1, sel2);
                rc = -EREMOTE;
        }
        trace_kvm_s390_handle_stsi(vcpu, fc, sel1, sel2, operand2);
        free_page(mem);
        kvm_s390_set_psw_cc(vcpu, 0);
        vcpu->run->s.regs.gprs[0] = 0;
        return rc;
out_no_data:
        kvm_s390_set_psw_cc(vcpu, 3);
out:
        free_page(mem);
        return rc;
}

int kvm_s390_handle_b2(struct kvm_vcpu *vcpu)
{
        switch (vcpu->arch.sie_block->ipa & 0x00ff) {
        case 0x02:
                return handle_stidp(vcpu);
        case 0x04:
                return handle_set_clock(vcpu);
        case 0x10:
                return handle_set_prefix(vcpu);
        case 0x11:
                return handle_store_prefix(vcpu);
        case 0x12:
                return handle_store_cpu_address(vcpu);
        case 0x14:
                return kvm_s390_handle_vsie(vcpu);
        case 0x21:
        case 0x50:
                return handle_ipte_interlock(vcpu);
        case 0x29:
                return handle_iske(vcpu);
        case 0x2a:
                return handle_rrbe(vcpu);
        case 0x2b:
                return handle_sske(vcpu);
        case 0x2c:
                return handle_test_block(vcpu);
        case 0x30:
        case 0x31:
        case 0x32:
        case 0x33:
        case 0x34:
        case 0x35:
        case 0x36:
        case 0x37:
        case 0x38:
        case 0x39:
        case 0x3a:
        case 0x3b:
        case 0x3c:
        case 0x5f:
        case 0x74:
        case 0x76:
                return handle_io_inst(vcpu);
        case 0x56:
                return handle_sthyi(vcpu);
        case 0x7d:
                return handle_stsi(vcpu);
        case 0xaf:
                return handle_pqap(vcpu);
        case 0xb1:
                return handle_stfl(vcpu);
        case 0xb2:
                return handle_lpswe(vcpu);
        default:
                return -EOPNOTSUPP;
        }
}

static int handle_epsw(struct kvm_vcpu *vcpu)
{
        int reg1, reg2;

        vcpu->stat.instruction_epsw++;

        kvm_s390_get_regs_rre(vcpu, &reg1, &reg2);

        /* This basically extracts the mask half of the psw. */
        vcpu->run->s.regs.gprs[reg1] &= 0xffffffff00000000UL;
        vcpu->run->s.regs.gprs[reg1] |= vcpu->arch.sie_block->gpsw.mask >> 32;
        if (reg2) {
                vcpu->run->s.regs.gprs[reg2] &= 0xffffffff00000000UL;
                vcpu->run->s.regs.gprs[reg2] |=
                        vcpu->arch.sie_block->gpsw.mask & 0x00000000ffffffffUL;
        }
        return 0;
}

#define PFMF_RESERVED   0xfffc0101UL
#define PFMF_SK         0x00020000UL
#define PFMF_CF         0x00010000UL
#define PFMF_UI         0x00008000UL
#define PFMF_FSC        0x00007000UL
#define PFMF_NQ         0x00000800UL
#define PFMF_MR         0x00000400UL
#define PFMF_MC         0x00000200UL
#define PFMF_KEY        0x000000feUL

static int handle_pfmf(struct kvm_vcpu *vcpu)
{
        bool mr = false, mc = false, nq;
        int reg1, reg2;
        unsigned long start, end;
        union skey key;

        vcpu->stat.instruction_pfmf++;

        kvm_s390_get_regs_rre(vcpu, &reg1, &reg2);

        if (!test_kvm_facility(vcpu->kvm, 8))
                return kvm_s390_inject_program_int(vcpu, PGM_OPERATION);

        if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
                return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);

        if (vcpu->run->s.regs.gprs[reg1] & PFMF_RESERVED)
                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);

        /* Only provide non-quiescing support if enabled for the guest */
        if (vcpu->run->s.regs.gprs[reg1] & PFMF_NQ &&
            !test_kvm_facility(vcpu->kvm, 14))
                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);

        /* Only provide conditional-SSKE support if enabled for the guest */
        if (vcpu->run->s.regs.gprs[reg1] & PFMF_SK &&
            test_kvm_facility(vcpu->kvm, 10)) {
                mr = vcpu->run->s.regs.gprs[reg1] & PFMF_MR;
                mc = vcpu->run->s.regs.gprs[reg1] & PFMF_MC;
        }

        nq = vcpu->run->s.regs.gprs[reg1] & PFMF_NQ;
        key.skey = vcpu->run->s.regs.gprs[reg1] & PFMF_KEY;
        start = vcpu->run->s.regs.gprs[reg2] & PAGE_MASK;
        start = kvm_s390_logical_to_effective(vcpu, start);

        if (vcpu->run->s.regs.gprs[reg1] & PFMF_CF) {
                if (kvm_s390_check_low_addr_prot_real(vcpu, start))
                        return kvm_s390_inject_prog_irq(vcpu, &vcpu->arch.pgm);
        }

        switch (vcpu->run->s.regs.gprs[reg1] & PFMF_FSC) {
        case 0x00000000:
                /* only 4k frames specify a real address */
                start = kvm_s390_real_to_abs(vcpu, start);
                end = (start + PAGE_SIZE) & ~(PAGE_SIZE - 1);
                break;
        case 0x00001000:
                end = (start + _SEGMENT_SIZE) & ~(_SEGMENT_SIZE - 1);
                break;
        case 0x00002000:
                /* only support 2G frame size if EDAT2 is available and we are
                   not in 24-bit addressing mode */
                if (!test_kvm_facility(vcpu->kvm, 78) ||
                    psw_bits(vcpu->arch.sie_block->gpsw).eaba == PSW_BITS_AMODE_24BIT)
                        return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
                end = (start + _REGION3_SIZE) & ~(_REGION3_SIZE - 1);
                break;
        default:
                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
        }

        while (start != end) {
                if (vcpu->run->s.regs.gprs[reg1] & PFMF_CF) {
                        if (kvm_clear_guest(vcpu->kvm, start, PAGE_SIZE))
                                return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
                }

                if (vcpu->run->s.regs.gprs[reg1] & PFMF_SK) {
                        int rc = kvm_s390_skey_check_enable(vcpu);

                        if (rc)
                                return rc;
                        scoped_guard(read_lock, &vcpu->kvm->mmu_lock) {
                                rc = dat_cond_set_storage_key(vcpu->arch.mc, vcpu->arch.gmap->asce,
                                                              gpa_to_gfn(start), key,
                                                              NULL, nq, mr, mc);
                        }
                        if (rc > 1)
                                return kvm_s390_inject_program_int(vcpu, rc);
                        if (rc == -ENOMEM) {
                                kvm_s390_mmu_cache_topup(vcpu->arch.mc);
                                continue;
                        }
                        if (rc < 0)
                                return rc;
                }
                start += PAGE_SIZE;
        }
        if (vcpu->run->s.regs.gprs[reg1] & PFMF_FSC) {
                if (psw_bits(vcpu->arch.sie_block->gpsw).eaba == PSW_BITS_AMODE_64BIT) {
                        vcpu->run->s.regs.gprs[reg2] = end;
                } else {
                        vcpu->run->s.regs.gprs[reg2] &= ~0xffffffffUL;
                        end = kvm_s390_logical_to_effective(vcpu, end);
                        vcpu->run->s.regs.gprs[reg2] |= end;
                }
        }
        return 0;
}

/*
 * Must be called with relevant read locks held (kvm->mm->mmap_lock, kvm->srcu)
 */
static inline int __do_essa(struct kvm_vcpu *vcpu, const int orc)
{
        int r1, r2, nappended, entries;
        union essa_state state;
        unsigned long *cbrlo;
        unsigned long gfn;
        bool dirtied;

        /*
         * We don't need to set SD.FPF.SK to 1 here, because if we have a
         * machine check here we either handle it or crash
         */

        kvm_s390_get_regs_rre(vcpu, &r1, &r2);
        gfn = vcpu->run->s.regs.gprs[r2] >> PAGE_SHIFT;
        entries = (vcpu->arch.sie_block->cbrlo & ~PAGE_MASK) >> 3;

        nappended = dat_perform_essa(vcpu->arch.gmap->asce, gfn, orc, &state, &dirtied);
        vcpu->run->s.regs.gprs[r1] = state.val;
        if (nappended < 0)
                return 0;
        /*
         * It is possible that all the normal 511 slots were full, in which case
         * we will now write in the 512th slot, which is reserved for host use.
         * In both cases we let the normal essa handling code process all the
         * slots, including the reserved one, if needed.
         */
        if (nappended > 0) {
                cbrlo = phys_to_virt(vcpu->arch.sie_block->cbrlo & PAGE_MASK);
                cbrlo[entries] = gfn << PAGE_SHIFT;
        }

        if (dirtied)
                atomic64_inc(&vcpu->kvm->arch.cmma_dirty_pages);

        return nappended;
}

static void _essa_clear_cbrl(struct kvm_vcpu *vcpu, unsigned long *cbrl, int len)
{
        union crste *crstep;
        union pgste pgste;
        union pte *ptep;
        int i;

        lockdep_assert_held(&vcpu->kvm->mmu_lock);

        for (i = 0; i < len; i++) {
                if (dat_entry_walk(NULL, gpa_to_gfn(cbrl[i]), vcpu->arch.gmap->asce,
                                   0, TABLE_TYPE_PAGE_TABLE, &crstep, &ptep))
                        continue;
                if (!ptep || ptep->s.pr)
                        continue;
                pgste = pgste_get_lock(ptep);
                if (pgste.usage == PGSTE_GPS_USAGE_UNUSED || pgste.zero)
                        gmap_helper_zap_one_page(vcpu->kvm->mm, cbrl[i]);
                pgste_set_unlock(ptep, pgste);
        }
}

static int handle_essa(struct kvm_vcpu *vcpu)
{
        lockdep_assert_held(&vcpu->kvm->srcu);

        /* entries expected to be 1FF */
        int entries = (vcpu->arch.sie_block->cbrlo & ~PAGE_MASK) >> 3;
        unsigned long *cbrlo;
        int i, orc;

        VCPU_EVENT(vcpu, 4, "ESSA: release %d pages", entries);
        vcpu->stat.instruction_essa++;
        if (!vcpu->kvm->arch.use_cmma)
                return kvm_s390_inject_program_int(vcpu, PGM_OPERATION);

        if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
                return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);
        /* Check for invalid operation request code */
        orc = (vcpu->arch.sie_block->ipb & 0xf0000000) >> 28;
        /* ORCs 0-6 are always valid */
        if (orc > (test_kvm_facility(vcpu->kvm, 147) ? ESSA_SET_STABLE_NODAT
                                                : ESSA_SET_STABLE_IF_RESIDENT))
                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);

        if (!vcpu->kvm->arch.migration_mode) {
                /*
                 * CMMA is enabled in the KVM settings, but is disabled in
                 * the SIE block and in the mm_context, and we are not doing
                 * a migration. Enable CMMA in the mm_context.
                 * Since we need to take a write lock to write to the context
                 * to avoid races with storage keys handling, we check if the
                 * value really needs to be written to; if the value is
                 * already correct, we do nothing and avoid the lock.
                 */
                set_bit(GMAP_FLAG_USES_CMM, &vcpu->arch.gmap->flags);
                /*
                 * If we are here, we are supposed to have CMMA enabled in
                 * the SIE block. Enabling CMMA works on a per-CPU basis,
                 * while the context use_cmma flag is per process.
                 * It's possible that the context flag is enabled and the
                 * SIE flag is not, so we set the flag always; if it was
                 * already set, nothing changes, otherwise we enable it
                 * on this CPU too.
                 */
                vcpu->arch.sie_block->ecb2 |= ECB2_CMMA;
                /* Retry the ESSA instruction */
                kvm_s390_retry_instr(vcpu);
        } else {
                scoped_guard(read_lock, &vcpu->kvm->mmu_lock)
                        i = __do_essa(vcpu, orc);
                if (i < 0)
                        return i;
                /* Account for the possible extra cbrl entry */
                entries += i;
        }
        /* reset nceo */
        vcpu->arch.sie_block->cbrlo &= PAGE_MASK;
        cbrlo = phys_to_virt(vcpu->arch.sie_block->cbrlo);

        mmap_read_lock(vcpu->kvm->mm);
        scoped_guard(read_lock, &vcpu->kvm->mmu_lock)
                _essa_clear_cbrl(vcpu, cbrlo, entries);
        mmap_read_unlock(vcpu->kvm->mm);

        return 0;
}

int kvm_s390_handle_b9(struct kvm_vcpu *vcpu)
{
        switch (vcpu->arch.sie_block->ipa & 0x00ff) {
        case 0x8a:
        case 0x8e:
        case 0x8f:
                return handle_ipte_interlock(vcpu);
        case 0x8d:
                return handle_epsw(vcpu);
        case 0xab:
                return handle_essa(vcpu);
        case 0xaf:
                return handle_pfmf(vcpu);
        default:
                return -EOPNOTSUPP;
        }
}

int kvm_s390_handle_lctl(struct kvm_vcpu *vcpu)
{
        int reg1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4;
        int reg3 = vcpu->arch.sie_block->ipa & 0x000f;
        int reg, rc, nr_regs;
        u32 ctl_array[16];
        u64 ga;
        u8 ar;

        vcpu->stat.instruction_lctl++;

        if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
                return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);

        ga = kvm_s390_get_base_disp_rs(vcpu, &ar);

        if (ga & 3)
                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);

        VCPU_EVENT(vcpu, 4, "LCTL: r1:%d, r3:%d, addr: 0x%llx", reg1, reg3, ga);
        trace_kvm_s390_handle_lctl(vcpu, 0, reg1, reg3, ga);

        nr_regs = ((reg3 - reg1) & 0xf) + 1;
        rc = read_guest(vcpu, ga, ar, ctl_array, nr_regs * sizeof(u32));
        if (rc)
                return kvm_s390_inject_prog_cond(vcpu, rc);
        reg = reg1;
        nr_regs = 0;
        do {
                vcpu->arch.sie_block->gcr[reg] &= 0xffffffff00000000ul;
                vcpu->arch.sie_block->gcr[reg] |= ctl_array[nr_regs++];
                if (reg == reg3)
                        break;
                reg = (reg + 1) % 16;
        } while (1);
        kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu);
        return 0;
}

int kvm_s390_handle_stctl(struct kvm_vcpu *vcpu)
{
        int reg1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4;
        int reg3 = vcpu->arch.sie_block->ipa & 0x000f;
        int reg, rc, nr_regs;
        u32 ctl_array[16];
        u64 ga;
        u8 ar;

        vcpu->stat.instruction_stctl++;

        if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
                return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);

        ga = kvm_s390_get_base_disp_rs(vcpu, &ar);

        if (ga & 3)
                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);

        VCPU_EVENT(vcpu, 4, "STCTL r1:%d, r3:%d, addr: 0x%llx", reg1, reg3, ga);
        trace_kvm_s390_handle_stctl(vcpu, 0, reg1, reg3, ga);

        reg = reg1;
        nr_regs = 0;
        do {
                ctl_array[nr_regs++] = vcpu->arch.sie_block->gcr[reg];
                if (reg == reg3)
                        break;
                reg = (reg + 1) % 16;
        } while (1);
        rc = write_guest(vcpu, ga, ar, ctl_array, nr_regs * sizeof(u32));
        return rc ? kvm_s390_inject_prog_cond(vcpu, rc) : 0;
}

static int handle_lctlg(struct kvm_vcpu *vcpu)
{
        int reg1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4;
        int reg3 = vcpu->arch.sie_block->ipa & 0x000f;
        int reg, rc, nr_regs;
        u64 ctl_array[16];
        u64 ga;
        u8 ar;

        vcpu->stat.instruction_lctlg++;

        if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
                return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);

        ga = kvm_s390_get_base_disp_rsy(vcpu, &ar);

        if (ga & 7)
                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);

        VCPU_EVENT(vcpu, 4, "LCTLG: r1:%d, r3:%d, addr: 0x%llx", reg1, reg3, ga);
        trace_kvm_s390_handle_lctl(vcpu, 1, reg1, reg3, ga);

        nr_regs = ((reg3 - reg1) & 0xf) + 1;
        rc = read_guest(vcpu, ga, ar, ctl_array, nr_regs * sizeof(u64));
        if (rc)
                return kvm_s390_inject_prog_cond(vcpu, rc);
        reg = reg1;
        nr_regs = 0;
        do {
                vcpu->arch.sie_block->gcr[reg] = ctl_array[nr_regs++];
                if (reg == reg3)
                        break;
                reg = (reg + 1) % 16;
        } while (1);
        kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu);
        return 0;
}

static int handle_stctg(struct kvm_vcpu *vcpu)
{
        int reg1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4;
        int reg3 = vcpu->arch.sie_block->ipa & 0x000f;
        int reg, rc, nr_regs;
        u64 ctl_array[16];
        u64 ga;
        u8 ar;

        vcpu->stat.instruction_stctg++;

        if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
                return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);

        ga = kvm_s390_get_base_disp_rsy(vcpu, &ar);

        if (ga & 7)
                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);

        VCPU_EVENT(vcpu, 4, "STCTG r1:%d, r3:%d, addr: 0x%llx", reg1, reg3, ga);
        trace_kvm_s390_handle_stctl(vcpu, 1, reg1, reg3, ga);

        reg = reg1;
        nr_regs = 0;
        do {
                ctl_array[nr_regs++] = vcpu->arch.sie_block->gcr[reg];
                if (reg == reg3)
                        break;
                reg = (reg + 1) % 16;
        } while (1);
        rc = write_guest(vcpu, ga, ar, ctl_array, nr_regs * sizeof(u64));
        return rc ? kvm_s390_inject_prog_cond(vcpu, rc) : 0;
}

int kvm_s390_handle_eb(struct kvm_vcpu *vcpu)
{
        switch (vcpu->arch.sie_block->ipb & 0x000000ff) {
        case 0x25:
                return handle_stctg(vcpu);
        case 0x2f:
                return handle_lctlg(vcpu);
        case 0x60:
        case 0x61:
        case 0x62:
                return handle_ri(vcpu);
        case 0x71:
                return handle_lpswey(vcpu);
        default:
                return -EOPNOTSUPP;
        }
}

static int handle_tprot(struct kvm_vcpu *vcpu)
{
        u64 address, operand2;
        unsigned long gpa;
        u8 access_key;
        bool writable;
        int ret, cc;
        u8 ar;

        vcpu->stat.instruction_tprot++;

        if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
                return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);

        kvm_s390_get_base_disp_sse(vcpu, &address, &operand2, &ar, NULL);
        access_key = (operand2 & 0xf0) >> 4;

        if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_DAT)
                ipte_lock(vcpu->kvm);

        ret = guest_translate_address_with_key(vcpu, address, ar, &gpa,
                                               GACC_STORE, access_key);
        if (ret == 0) {
                gfn_to_hva_prot(vcpu->kvm, gpa_to_gfn(gpa), &writable);
        } else if (ret == PGM_PROTECTION) {
                writable = false;
                /* Write protected? Try again with read-only... */
                ret = guest_translate_address_with_key(vcpu, address, ar, &gpa,
                                                       GACC_FETCH, access_key);
        }
        if (ret >= 0) {
                cc = -1;

                /* Fetching permitted; storing permitted */
                if (ret == 0 && writable)
                        cc = 0;
                /* Fetching permitted; storing not permitted */
                else if (ret == 0 && !writable)
                        cc = 1;
                /* Fetching not permitted; storing not permitted */
                else if (ret == PGM_PROTECTION)
                        cc = 2;
                /* Translation not available */
                else if (ret != PGM_ADDRESSING && ret != PGM_TRANSLATION_SPEC)
                        cc = 3;

                if (cc != -1) {
                        kvm_s390_set_psw_cc(vcpu, cc);
                        ret = 0;
                } else {
                        ret = kvm_s390_inject_program_int(vcpu, ret);
                }
        }

        if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_DAT)
                ipte_unlock(vcpu->kvm);
        return ret;
}

int kvm_s390_handle_e5(struct kvm_vcpu *vcpu)
{
        switch (vcpu->arch.sie_block->ipa & 0x00ff) {
        case 0x01:
                return handle_tprot(vcpu);
        default:
                return -EOPNOTSUPP;
        }
}

static int handle_sckpf(struct kvm_vcpu *vcpu)
{
        u32 value;

        vcpu->stat.instruction_sckpf++;

        if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
                return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);

        if (vcpu->run->s.regs.gprs[0] & 0x00000000ffff0000)
                return kvm_s390_inject_program_int(vcpu,
                                                   PGM_SPECIFICATION);

        value = vcpu->run->s.regs.gprs[0] & 0x000000000000ffff;
        vcpu->arch.sie_block->todpr = value;

        return 0;
}

static int handle_ptff(struct kvm_vcpu *vcpu)
{
        vcpu->stat.instruction_ptff++;

        /* we don't emulate any control instructions yet */
        kvm_s390_set_psw_cc(vcpu, 3);
        return 0;
}

int kvm_s390_handle_01(struct kvm_vcpu *vcpu)
{
        switch (vcpu->arch.sie_block->ipa & 0x00ff) {
        case 0x04:
                return handle_ptff(vcpu);
        case 0x07:
                return handle_sckpf(vcpu);
        default:
                return -EOPNOTSUPP;
        }
}