// SPDX-License-Identifier: GPL-2.0+
/*
 *  Copyright IBM Corp. 2001, 2018
 *  Author(s): Robert Burroughs
 *             Eric Rossman (edrossma@us.ibm.com)
 *             Cornelia Huck <cornelia.huck@de.ibm.com>
 *
 *  Hotplug & misc device support: Jochen Roehrig (roehrig@de.ibm.com)
 *  Major cleanup & driver split: Martin Schwidefsky <schwidefsky@de.ibm.com>
 *                                Ralph Wuerthner <rwuerthn@de.ibm.com>
 *  MSGTYPE restruct:             Holger Dengler <hd@linux.vnet.ibm.com>
 *  Multiple device nodes: Harald Freudenberger <freude@linux.ibm.com>
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/miscdevice.h>
#include <linux/fs.h>
#include <linux/compat.h>
#include <linux/slab.h>
#include <linux/atomic.h>
#include <linux/uaccess.h>
#include <linux/hw_random.h>
#include <linux/debugfs.h>
#include <linux/cdev.h>
#include <linux/ctype.h>
#include <linux/capability.h>
#include <asm/debug.h>

#define CREATE_TRACE_POINTS
#include <asm/trace/zcrypt.h>

#include "zcrypt_api.h"
#include "zcrypt_debug.h"

#include "zcrypt_msgtype6.h"
#include "zcrypt_msgtype50.h"
#include "zcrypt_ccamisc.h"
#include "zcrypt_ep11misc.h"

/*
 * Module description.
 */
MODULE_AUTHOR("IBM Corporation");
MODULE_DESCRIPTION("Cryptographic Coprocessor interface, " \
                   "Copyright IBM Corp. 2001, 2012");
MODULE_LICENSE("GPL");

/*
 * zcrypt tracepoint functions
 */
EXPORT_TRACEPOINT_SYMBOL(s390_zcrypt_req);
EXPORT_TRACEPOINT_SYMBOL(s390_zcrypt_rep);

static int zcrypt_hwrng_seed = 1;
module_param_named(hwrng_seed, zcrypt_hwrng_seed, int, 0440);
MODULE_PARM_DESC(hwrng_seed, "Turn on/off hwrng auto seed, default is 1 (on).");

DEFINE_SPINLOCK(zcrypt_list_lock);
LIST_HEAD(zcrypt_card_list);

static atomic_t zcrypt_open_count = ATOMIC_INIT(0);
static atomic_t zcrypt_rescan_count = ATOMIC_INIT(0);

atomic_t zcrypt_rescan_req = ATOMIC_INIT(0);
EXPORT_SYMBOL(zcrypt_rescan_req);

static LIST_HEAD(zcrypt_ops_list);

/* Zcrypt related debug feature stuff. */
debug_info_t *zcrypt_dbf_info;

/*
 * Process a rescan of the transport layer.
 *
 * Returns 1, if the rescan has been processed, otherwise 0.
 */
static inline int zcrypt_process_rescan(void)
{
        if (atomic_read(&zcrypt_rescan_req)) {
                atomic_set(&zcrypt_rescan_req, 0);
                atomic_inc(&zcrypt_rescan_count);
                ap_bus_force_rescan();
                ZCRYPT_DBF_INFO("%s rescan count=%07d\n", __func__,
                                atomic_inc_return(&zcrypt_rescan_count));
                return 1;
        }
        return 0;
}

void zcrypt_msgtype_register(struct zcrypt_ops *zops)
{
        list_add_tail(&zops->list, &zcrypt_ops_list);
}

void zcrypt_msgtype_unregister(struct zcrypt_ops *zops)
{
        list_del_init(&zops->list);
}

struct zcrypt_ops *zcrypt_msgtype(unsigned char *name, int variant)
{
        struct zcrypt_ops *zops;

        list_for_each_entry(zops, &zcrypt_ops_list, list)
                if ((zops->variant == variant) &&
                    (!strncmp(zops->name, name, sizeof(zops->name))))
                        return zops;
        return NULL;
}
EXPORT_SYMBOL(zcrypt_msgtype);

/*
 * Multi device nodes extension functions.
 */

#ifdef CONFIG_ZCRYPT_MULTIDEVNODES

struct zcdn_device;

static struct class *zcrypt_class;
static dev_t zcrypt_devt;
static struct cdev zcrypt_cdev;

struct zcdn_device {
        struct device device;
        struct ap_perms perms;
};

#define to_zcdn_dev(x) container_of((x), struct zcdn_device, device)

#define ZCDN_MAX_NAME 32

static int zcdn_create(const char *name);
static int zcdn_destroy(const char *name);

/*
 * Find zcdn device by name.
 * Returns reference to the zcdn device which needs to be released
 * with put_device() after use.
 */
static inline struct zcdn_device *find_zcdndev_by_name(const char *name)
{
        struct device *dev = class_find_device_by_name(zcrypt_class, name);

        return dev ? to_zcdn_dev(dev) : NULL;
}

/*
 * Find zcdn device by devt value.
 * Returns reference to the zcdn device which needs to be released
 * with put_device() after use.
 */
static inline struct zcdn_device *find_zcdndev_by_devt(dev_t devt)
{
        struct device *dev = class_find_device_by_devt(zcrypt_class, devt);

        return dev ? to_zcdn_dev(dev) : NULL;
}

static ssize_t ioctlmask_show(struct device *dev,
                              struct device_attribute *attr,
                              char *buf)
{
        int i, rc;
        struct zcdn_device *zcdndev = to_zcdn_dev(dev);

        if (mutex_lock_interruptible(&ap_perms_mutex))
                return -ERESTARTSYS;

        buf[0] = '0';
        buf[1] = 'x';
        for (i = 0; i < sizeof(zcdndev->perms.ioctlm) / sizeof(long); i++)
                snprintf(buf + 2 + 2 * i * sizeof(long),
                         PAGE_SIZE - 2 - 2 * i * sizeof(long),
                         "%016lx", zcdndev->perms.ioctlm[i]);
        buf[2 + 2 * i * sizeof(long)] = '\n';
        buf[2 + 2 * i * sizeof(long) + 1] = '\0';
        rc = 2 + 2 * i * sizeof(long) + 1;

        mutex_unlock(&ap_perms_mutex);

        return rc;
}

static ssize_t ioctlmask_store(struct device *dev,
                               struct device_attribute *attr,
                               const char *buf, size_t count)
{
        int rc;
        struct zcdn_device *zcdndev = to_zcdn_dev(dev);

        rc = ap_parse_mask_str(buf, zcdndev->perms.ioctlm,
                               AP_IOCTLS, &ap_perms_mutex);
        if (rc)
                return rc;

        return count;
}

static DEVICE_ATTR_RW(ioctlmask);

static ssize_t apmask_show(struct device *dev,
                           struct device_attribute *attr,
                           char *buf)
{
        int i, rc;
        struct zcdn_device *zcdndev = to_zcdn_dev(dev);

        if (mutex_lock_interruptible(&ap_perms_mutex))
                return -ERESTARTSYS;

        buf[0] = '0';
        buf[1] = 'x';
        for (i = 0; i < sizeof(zcdndev->perms.apm) / sizeof(long); i++)
                snprintf(buf + 2 + 2 * i * sizeof(long),
                         PAGE_SIZE - 2 - 2 * i * sizeof(long),
                         "%016lx", zcdndev->perms.apm[i]);
        buf[2 + 2 * i * sizeof(long)] = '\n';
        buf[2 + 2 * i * sizeof(long) + 1] = '\0';
        rc = 2 + 2 * i * sizeof(long) + 1;

        mutex_unlock(&ap_perms_mutex);

        return rc;
}

static ssize_t apmask_store(struct device *dev,
                            struct device_attribute *attr,
                            const char *buf, size_t count)
{
        int rc;
        struct zcdn_device *zcdndev = to_zcdn_dev(dev);

        rc = ap_parse_mask_str(buf, zcdndev->perms.apm,
                               AP_DEVICES, &ap_perms_mutex);
        if (rc)
                return rc;

        return count;
}

static DEVICE_ATTR_RW(apmask);

static ssize_t aqmask_show(struct device *dev,
                           struct device_attribute *attr,
                           char *buf)
{
        int i, rc;
        struct zcdn_device *zcdndev = to_zcdn_dev(dev);

        if (mutex_lock_interruptible(&ap_perms_mutex))
                return -ERESTARTSYS;

        buf[0] = '0';
        buf[1] = 'x';
        for (i = 0; i < sizeof(zcdndev->perms.aqm) / sizeof(long); i++)
                snprintf(buf + 2 + 2 * i * sizeof(long),
                         PAGE_SIZE - 2 - 2 * i * sizeof(long),
                         "%016lx", zcdndev->perms.aqm[i]);
        buf[2 + 2 * i * sizeof(long)] = '\n';
        buf[2 + 2 * i * sizeof(long) + 1] = '\0';
        rc = 2 + 2 * i * sizeof(long) + 1;

        mutex_unlock(&ap_perms_mutex);

        return rc;
}

static ssize_t aqmask_store(struct device *dev,
                            struct device_attribute *attr,
                            const char *buf, size_t count)
{
        int rc;
        struct zcdn_device *zcdndev = to_zcdn_dev(dev);

        rc = ap_parse_mask_str(buf, zcdndev->perms.aqm,
                               AP_DOMAINS, &ap_perms_mutex);
        if (rc)
                return rc;

        return count;
}

static DEVICE_ATTR_RW(aqmask);

static struct attribute *zcdn_dev_attrs[] = {
        &dev_attr_ioctlmask.attr,
        &dev_attr_apmask.attr,
        &dev_attr_aqmask.attr,
        NULL
};

static struct attribute_group zcdn_dev_attr_group = {
        .attrs = zcdn_dev_attrs
};

static const struct attribute_group *zcdn_dev_attr_groups[] = {
        &zcdn_dev_attr_group,
        NULL
};

static ssize_t zcdn_create_store(struct class *class,
                                 struct class_attribute *attr,
                                 const char *buf, size_t count)
{
        int rc;
        char name[ZCDN_MAX_NAME];

        strncpy(name, skip_spaces(buf), sizeof(name));
        name[sizeof(name) - 1] = '\0';

        rc = zcdn_create(strim(name));

        return rc ? rc : count;
}

static const struct class_attribute class_attr_zcdn_create =
        __ATTR(create, 0600, NULL, zcdn_create_store);

static ssize_t zcdn_destroy_store(struct class *class,
                                  struct class_attribute *attr,
                                  const char *buf, size_t count)
{
        int rc;
        char name[ZCDN_MAX_NAME];

        strncpy(name, skip_spaces(buf), sizeof(name));
        name[sizeof(name) - 1] = '\0';

        rc = zcdn_destroy(strim(name));

        return rc ? rc : count;
}

static const struct class_attribute class_attr_zcdn_destroy =
        __ATTR(destroy, 0600, NULL, zcdn_destroy_store);

static void zcdn_device_release(struct device *dev)
{
        struct zcdn_device *zcdndev = to_zcdn_dev(dev);

        ZCRYPT_DBF_INFO("%s releasing zcdn device %d:%d\n",
                        __func__, MAJOR(dev->devt), MINOR(dev->devt));

        kfree(zcdndev);
}

static int zcdn_create(const char *name)
{
        dev_t devt;
        int i, rc = 0;
        char nodename[ZCDN_MAX_NAME];
        struct zcdn_device *zcdndev;

        if (mutex_lock_interruptible(&ap_perms_mutex))
                return -ERESTARTSYS;

        /* check if device node with this name already exists */
        if (name[0]) {
                zcdndev = find_zcdndev_by_name(name);
                if (zcdndev) {
                        put_device(&zcdndev->device);
                        rc = -EEXIST;
                        goto unlockout;
                }
        }

        /* find an unused minor number */
        for (i = 0; i < ZCRYPT_MAX_MINOR_NODES; i++) {
                devt = MKDEV(MAJOR(zcrypt_devt), MINOR(zcrypt_devt) + i);
                zcdndev = find_zcdndev_by_devt(devt);
                if (zcdndev)
                        put_device(&zcdndev->device);
                else
                        break;
        }
        if (i == ZCRYPT_MAX_MINOR_NODES) {
                rc = -ENOSPC;
                goto unlockout;
        }

        /* alloc and prepare a new zcdn device */
        zcdndev = kzalloc(sizeof(*zcdndev), GFP_KERNEL);
        if (!zcdndev) {
                rc = -ENOMEM;
                goto unlockout;
        }
        zcdndev->device.release = zcdn_device_release;
        zcdndev->device.class = zcrypt_class;
        zcdndev->device.devt = devt;
        zcdndev->device.groups = zcdn_dev_attr_groups;
        if (name[0])
                strncpy(nodename, name, sizeof(nodename));
        else
                snprintf(nodename, sizeof(nodename),
                         ZCRYPT_NAME "_%d", (int) MINOR(devt));
        nodename[sizeof(nodename)-1] = '\0';
        if (dev_set_name(&zcdndev->device, nodename)) {
                rc = -EINVAL;
                goto unlockout;
        }
        rc = device_register(&zcdndev->device);
        if (rc) {
                put_device(&zcdndev->device);
                goto unlockout;
        }

        ZCRYPT_DBF_INFO("%s created zcdn device %d:%d\n",
                        __func__, MAJOR(devt), MINOR(devt));

unlockout:
        mutex_unlock(&ap_perms_mutex);
        return rc;
}

static int zcdn_destroy(const char *name)
{
        int rc = 0;
        struct zcdn_device *zcdndev;

        if (mutex_lock_interruptible(&ap_perms_mutex))
                return -ERESTARTSYS;

        /* try to find this zcdn device */
        zcdndev = find_zcdndev_by_name(name);
        if (!zcdndev) {
                rc = -ENOENT;
                goto unlockout;
        }

        /*
         * The zcdn device is not hard destroyed. It is subject to
         * reference counting and thus just needs to be unregistered.
         */
        put_device(&zcdndev->device);
        device_unregister(&zcdndev->device);

unlockout:
        mutex_unlock(&ap_perms_mutex);
        return rc;
}

static void zcdn_destroy_all(void)
{
        int i;
        dev_t devt;
        struct zcdn_device *zcdndev;

        mutex_lock(&ap_perms_mutex);
        for (i = 0; i < ZCRYPT_MAX_MINOR_NODES; i++) {
                devt = MKDEV(MAJOR(zcrypt_devt), MINOR(zcrypt_devt) + i);
                zcdndev = find_zcdndev_by_devt(devt);
                if (zcdndev) {
                        put_device(&zcdndev->device);
                        device_unregister(&zcdndev->device);
                }
        }
        mutex_unlock(&ap_perms_mutex);
}

#endif

/*
 * zcrypt_read (): Not supported beyond zcrypt 1.3.1.
 *
 * This function is not supported beyond zcrypt 1.3.1.
 */
static ssize_t zcrypt_read(struct file *filp, char __user *buf,
                           size_t count, loff_t *f_pos)
{
        return -EPERM;
}

/*
 * zcrypt_write(): Not allowed.
 *
 * Write is is not allowed
 */
static ssize_t zcrypt_write(struct file *filp, const char __user *buf,
                            size_t count, loff_t *f_pos)
{
        return -EPERM;
}

/*
 * zcrypt_open(): Count number of users.
 *
 * Device open function to count number of users.
 */
static int zcrypt_open(struct inode *inode, struct file *filp)
{
        struct ap_perms *perms = &ap_perms;

#ifdef CONFIG_ZCRYPT_MULTIDEVNODES
        if (filp->f_inode->i_cdev == &zcrypt_cdev) {
                struct zcdn_device *zcdndev;

                if (mutex_lock_interruptible(&ap_perms_mutex))
                        return -ERESTARTSYS;
                zcdndev = find_zcdndev_by_devt(filp->f_inode->i_rdev);
                /* find returns a reference, no get_device() needed */
                mutex_unlock(&ap_perms_mutex);
                if (zcdndev)
                        perms = &zcdndev->perms;
        }
#endif
        filp->private_data = (void *) perms;

        atomic_inc(&zcrypt_open_count);
        return stream_open(inode, filp);
}

/*
 * zcrypt_release(): Count number of users.
 *
 * Device close function to count number of users.
 */
static int zcrypt_release(struct inode *inode, struct file *filp)
{
#ifdef CONFIG_ZCRYPT_MULTIDEVNODES
        if (filp->f_inode->i_cdev == &zcrypt_cdev) {
                struct zcdn_device *zcdndev;

                mutex_lock(&ap_perms_mutex);
                zcdndev = find_zcdndev_by_devt(filp->f_inode->i_rdev);
                mutex_unlock(&ap_perms_mutex);
                if (zcdndev) {
                        /* 2 puts here: one for find, one for open */
                        put_device(&zcdndev->device);
                        put_device(&zcdndev->device);
                }
        }
#endif

        atomic_dec(&zcrypt_open_count);
        return 0;
}

static inline int zcrypt_check_ioctl(struct ap_perms *perms,
                                     unsigned int cmd)
{
        int rc = -EPERM;
        int ioctlnr = (cmd & _IOC_NRMASK) >> _IOC_NRSHIFT;

        if (ioctlnr > 0 && ioctlnr < AP_IOCTLS) {
                if (test_bit_inv(ioctlnr, perms->ioctlm))
                        rc = 0;
        }

        if (rc)
                ZCRYPT_DBF_WARN("%s ioctl check failed: ioctlnr=0x%04x rc=%d\n",
                                __func__, ioctlnr, rc);

        return rc;
}

static inline bool zcrypt_check_card(struct ap_perms *perms, int card)
{
        return test_bit_inv(card, perms->apm) ? true : false;
}

static inline bool zcrypt_check_queue(struct ap_perms *perms, int queue)
{
        return test_bit_inv(queue, perms->aqm) ? true : false;
}

static inline struct zcrypt_queue *zcrypt_pick_queue(struct zcrypt_card *zc,
                                                     struct zcrypt_queue *zq,
                                                     struct module **pmod,
                                                     unsigned int weight)
{
        if (!zq || !try_module_get(zq->queue->ap_dev.device.driver->owner))
                return NULL;
        zcrypt_queue_get(zq);
        get_device(&zq->queue->ap_dev.device);
        atomic_add(weight, &zc->load);
        atomic_add(weight, &zq->load);
        zq->request_count++;
        *pmod = zq->queue->ap_dev.device.driver->owner;
        return zq;
}

static inline void zcrypt_drop_queue(struct zcrypt_card *zc,
                                     struct zcrypt_queue *zq,
                                     struct module *mod,
                                     unsigned int weight)
{
        zq->request_count--;
        atomic_sub(weight, &zc->load);
        atomic_sub(weight, &zq->load);
        put_device(&zq->queue->ap_dev.device);
        zcrypt_queue_put(zq);
        module_put(mod);
}

static inline bool zcrypt_card_compare(struct zcrypt_card *zc,
                                       struct zcrypt_card *pref_zc,
                                       unsigned int weight,
                                       unsigned int pref_weight)
{
        if (!pref_zc)
                return true;
        weight += atomic_read(&zc->load);
        pref_weight += atomic_read(&pref_zc->load);
        if (weight == pref_weight)
                return atomic64_read(&zc->card->total_request_count) <
                        atomic64_read(&pref_zc->card->total_request_count);
        return weight < pref_weight;
}

static inline bool zcrypt_queue_compare(struct zcrypt_queue *zq,
                                        struct zcrypt_queue *pref_zq,
                                        unsigned int weight,
                                        unsigned int pref_weight)
{
        if (!pref_zq)
                return true;
        weight += atomic_read(&zq->load);
        pref_weight += atomic_read(&pref_zq->load);
        if (weight == pref_weight)
                return zq->queue->total_request_count <
                        pref_zq->queue->total_request_count;
        return weight < pref_weight;
}

/*
 * zcrypt ioctls.
 */
static long zcrypt_rsa_modexpo(struct ap_perms *perms,
                               struct zcrypt_track *tr,
                               struct ica_rsa_modexpo *mex)
{
        struct zcrypt_card *zc, *pref_zc;
        struct zcrypt_queue *zq, *pref_zq;
        struct ap_message ap_msg;
        unsigned int wgt = 0, pref_wgt = 0;
        unsigned int func_code;
        int cpen, qpen, qid = 0, rc = -ENODEV;
        struct module *mod;

        trace_s390_zcrypt_req(mex, TP_ICARSAMODEXPO);

        ap_init_message(&ap_msg);

#ifdef CONFIG_ZCRYPT_DEBUG
        if (tr && tr->fi.cmd)
                ap_msg.fi.cmd = tr->fi.cmd;
#endif

        if (mex->outputdatalength < mex->inputdatalength) {
                func_code = 0;
                rc = -EINVAL;
                goto out;
        }

        /*
         * As long as outputdatalength is big enough, we can set the
         * outputdatalength equal to the inputdatalength, since that is the
         * number of bytes we will copy in any case
         */
        mex->outputdatalength = mex->inputdatalength;

        rc = get_rsa_modex_fc(mex, &func_code);
        if (rc)
                goto out;

        pref_zc = NULL;
        pref_zq = NULL;
        spin_lock(&zcrypt_list_lock);
        for_each_zcrypt_card(zc) {
                /* Check for useable accelarator or CCA card */
                if (!zc->online || !zc->card->config ||
                    !(zc->card->functions & 0x18000000))
                        continue;
                /* Check for size limits */
                if (zc->min_mod_size > mex->inputdatalength ||
                    zc->max_mod_size < mex->inputdatalength)
                        continue;
                /* check if device node has admission for this card */
                if (!zcrypt_check_card(perms, zc->card->id))
                        continue;
                /* get weight index of the card device  */
                wgt = zc->speed_rating[func_code];
                /* penalty if this msg was previously sent via this card */
                cpen = (tr && tr->again_counter && tr->last_qid &&
                        AP_QID_CARD(tr->last_qid) == zc->card->id) ?
                        TRACK_AGAIN_CARD_WEIGHT_PENALTY : 0;
                if (!zcrypt_card_compare(zc, pref_zc, wgt + cpen, pref_wgt))
                        continue;
                for_each_zcrypt_queue(zq, zc) {
                        /* check if device is useable and eligible */
                        if (!zq->online || !zq->ops->rsa_modexpo ||
                            !zq->queue->config)
                                continue;
                        /* check if device node has admission for this queue */
                        if (!zcrypt_check_queue(perms,
                                                AP_QID_QUEUE(zq->queue->qid)))
                                continue;
                        /* penalty if the msg was previously sent at this qid */
                        qpen = (tr && tr->again_counter && tr->last_qid &&
                                tr->last_qid == zq->queue->qid) ?
                                TRACK_AGAIN_QUEUE_WEIGHT_PENALTY : 0;
                        if (!zcrypt_queue_compare(zq, pref_zq,
                                                  wgt + cpen + qpen, pref_wgt))
                                continue;
                        pref_zc = zc;
                        pref_zq = zq;
                        pref_wgt = wgt + cpen + qpen;
                }
        }
        pref_zq = zcrypt_pick_queue(pref_zc, pref_zq, &mod, wgt);
        spin_unlock(&zcrypt_list_lock);

        if (!pref_zq) {
                rc = -ENODEV;
                goto out;
        }

        qid = pref_zq->queue->qid;
        rc = pref_zq->ops->rsa_modexpo(pref_zq, mex, &ap_msg);

        spin_lock(&zcrypt_list_lock);
        zcrypt_drop_queue(pref_zc, pref_zq, mod, wgt);
        spin_unlock(&zcrypt_list_lock);

out:
        ap_release_message(&ap_msg);
        if (tr) {
                tr->last_rc = rc;
                tr->last_qid = qid;
        }
        trace_s390_zcrypt_rep(mex, func_code, rc,
                              AP_QID_CARD(qid), AP_QID_QUEUE(qid));
        return rc;
}

static long zcrypt_rsa_crt(struct ap_perms *perms,
                           struct zcrypt_track *tr,
                           struct ica_rsa_modexpo_crt *crt)
{
        struct zcrypt_card *zc, *pref_zc;
        struct zcrypt_queue *zq, *pref_zq;
        struct ap_message ap_msg;
        unsigned int wgt = 0, pref_wgt = 0;
        unsigned int func_code;
        int cpen, qpen, qid = 0, rc = -ENODEV;
        struct module *mod;

        trace_s390_zcrypt_req(crt, TP_ICARSACRT);

        ap_init_message(&ap_msg);

#ifdef CONFIG_ZCRYPT_DEBUG
        if (tr && tr->fi.cmd)
                ap_msg.fi.cmd = tr->fi.cmd;
#endif

        if (crt->outputdatalength < crt->inputdatalength) {
                func_code = 0;
                rc = -EINVAL;
                goto out;
        }

        /*
         * As long as outputdatalength is big enough, we can set the
         * outputdatalength equal to the inputdatalength, since that is the
         * number of bytes we will copy in any case
         */
        crt->outputdatalength = crt->inputdatalength;

        rc = get_rsa_crt_fc(crt, &func_code);
        if (rc)
                goto out;

        pref_zc = NULL;
        pref_zq = NULL;
        spin_lock(&zcrypt_list_lock);
        for_each_zcrypt_card(zc) {
                /* Check for useable accelarator or CCA card */
                if (!zc->online || !zc->card->config ||
                    !(zc->card->functions & 0x18000000))
                        continue;
                /* Check for size limits */
                if (zc->min_mod_size > crt->inputdatalength ||
                    zc->max_mod_size < crt->inputdatalength)
                        continue;
                /* check if device node has admission for this card */
                if (!zcrypt_check_card(perms, zc->card->id))
                        continue;
                /* get weight index of the card device  */
                wgt = zc->speed_rating[func_code];
                /* penalty if this msg was previously sent via this card */
                cpen = (tr && tr->again_counter && tr->last_qid &&
                        AP_QID_CARD(tr->last_qid) == zc->card->id) ?
                        TRACK_AGAIN_CARD_WEIGHT_PENALTY : 0;
                if (!zcrypt_card_compare(zc, pref_zc, wgt + cpen, pref_wgt))
                        continue;
                for_each_zcrypt_queue(zq, zc) {
                        /* check if device is useable and eligible */
                        if (!zq->online || !zq->ops->rsa_modexpo_crt ||
                            !zq->queue->config)
                                continue;
                        /* check if device node has admission for this queue */
                        if (!zcrypt_check_queue(perms,
                                                AP_QID_QUEUE(zq->queue->qid)))
                                continue;
                        /* penalty if the msg was previously sent at this qid */
                        qpen = (tr && tr->again_counter && tr->last_qid &&
                                tr->last_qid == zq->queue->qid) ?
                                TRACK_AGAIN_QUEUE_WEIGHT_PENALTY : 0;
                        if (!zcrypt_queue_compare(zq, pref_zq,
                                                  wgt + cpen + qpen, pref_wgt))
                                continue;
                        pref_zc = zc;
                        pref_zq = zq;
                        pref_wgt = wgt + cpen + qpen;
                }
        }
        pref_zq = zcrypt_pick_queue(pref_zc, pref_zq, &mod, wgt);
        spin_unlock(&zcrypt_list_lock);

        if (!pref_zq) {
                rc = -ENODEV;
                goto out;
        }

        qid = pref_zq->queue->qid;
        rc = pref_zq->ops->rsa_modexpo_crt(pref_zq, crt, &ap_msg);

        spin_lock(&zcrypt_list_lock);
        zcrypt_drop_queue(pref_zc, pref_zq, mod, wgt);
        spin_unlock(&zcrypt_list_lock);

out:
        ap_release_message(&ap_msg);
        if (tr) {
                tr->last_rc = rc;
                tr->last_qid = qid;
        }
        trace_s390_zcrypt_rep(crt, func_code, rc,
                              AP_QID_CARD(qid), AP_QID_QUEUE(qid));
        return rc;
}

static long _zcrypt_send_cprb(bool userspace, struct ap_perms *perms,
                              struct zcrypt_track *tr,
                              struct ica_xcRB *xcRB)
{
        struct zcrypt_card *zc, *pref_zc;
        struct zcrypt_queue *zq, *pref_zq;
        struct ap_message ap_msg;
        unsigned int wgt = 0, pref_wgt = 0;
        unsigned int func_code;
        unsigned short *domain, tdom;
        int cpen, qpen, qid = 0, rc = -ENODEV;
        struct module *mod;

        trace_s390_zcrypt_req(xcRB, TB_ZSECSENDCPRB);

        xcRB->status = 0;
        ap_init_message(&ap_msg);

#ifdef CONFIG_ZCRYPT_DEBUG
        if (tr && tr->fi.cmd)
                ap_msg.fi.cmd = tr->fi.cmd;
        if (tr && tr->fi.action == AP_FI_ACTION_CCA_AGENT_FF) {
                ZCRYPT_DBF_WARN("%s fi cmd 0x%04x: forcing invalid agent_ID 'FF'\n",
                                __func__, tr->fi.cmd);
                xcRB->agent_ID = 0x4646;
        }
#endif

        rc = get_cprb_fc(userspace, xcRB, &ap_msg, &func_code, &domain);
        if (rc)
                goto out;

        /*
         * If a valid target domain is set and this domain is NOT a usage
         * domain but a control only domain, autoselect target domain.
         */
        tdom = *domain;
        if (tdom < AP_DOMAINS &&
            !ap_test_config_usage_domain(tdom) &&
            ap_test_config_ctrl_domain(tdom))
                tdom = AUTOSEL_DOM;

        pref_zc = NULL;
        pref_zq = NULL;
        spin_lock(&zcrypt_list_lock);
        for_each_zcrypt_card(zc) {
                /* Check for useable CCA card */
                if (!zc->online || !zc->card->config ||
                    !(zc->card->functions & 0x10000000))
                        continue;
                /* Check for user selected CCA card */
                if (xcRB->user_defined != AUTOSELECT &&
                    xcRB->user_defined != zc->card->id)
                        continue;
                /* check if request size exceeds card max msg size */
                if (ap_msg.len > zc->card->maxmsgsize)
                        continue;
                /* check if device node has admission for this card */
                if (!zcrypt_check_card(perms, zc->card->id))
                        continue;
                /* get weight index of the card device  */
                wgt = speed_idx_cca(func_code) * zc->speed_rating[SECKEY];
                /* penalty if this msg was previously sent via this card */
                cpen = (tr && tr->again_counter && tr->last_qid &&
                        AP_QID_CARD(tr->last_qid) == zc->card->id) ?
                        TRACK_AGAIN_CARD_WEIGHT_PENALTY : 0;
                if (!zcrypt_card_compare(zc, pref_zc, wgt + cpen, pref_wgt))
                        continue;
                for_each_zcrypt_queue(zq, zc) {
                        /* check for device useable and eligible */
                        if (!zq->online ||
                            !zq->ops->send_cprb ||
                            !zq->queue->config ||
                            (tdom != AUTOSEL_DOM &&
                             tdom != AP_QID_QUEUE(zq->queue->qid)))
                                continue;
                        /* check if device node has admission for this queue */
                        if (!zcrypt_check_queue(perms,
                                                AP_QID_QUEUE(zq->queue->qid)))
                                continue;
                        /* penalty if the msg was previously sent at this qid */
                        qpen = (tr && tr->again_counter && tr->last_qid &&
                                tr->last_qid == zq->queue->qid) ?
                                TRACK_AGAIN_QUEUE_WEIGHT_PENALTY : 0;
                        if (!zcrypt_queue_compare(zq, pref_zq,
                                                  wgt + cpen + qpen, pref_wgt))
                                continue;
                        pref_zc = zc;
                        pref_zq = zq;
                        pref_wgt = wgt + cpen + qpen;
                }
        }
        pref_zq = zcrypt_pick_queue(pref_zc, pref_zq, &mod, wgt);
        spin_unlock(&zcrypt_list_lock);

        if (!pref_zq) {
                rc = -ENODEV;
                goto out;
        }

        /* in case of auto select, provide the correct domain */
        qid = pref_zq->queue->qid;
        if (*domain == AUTOSEL_DOM)
                *domain = AP_QID_QUEUE(qid);

#ifdef CONFIG_ZCRYPT_DEBUG
        if (tr && tr->fi.action == AP_FI_ACTION_CCA_DOM_INVAL) {
                ZCRYPT_DBF_WARN("%s fi cmd 0x%04x: forcing invalid domain\n",
                                __func__, tr->fi.cmd);
                *domain = 99;
        }
#endif

        rc = pref_zq->ops->send_cprb(userspace, pref_zq, xcRB, &ap_msg);

        spin_lock(&zcrypt_list_lock);
        zcrypt_drop_queue(pref_zc, pref_zq, mod, wgt);
        spin_unlock(&zcrypt_list_lock);

out:
        ap_release_message(&ap_msg);
        if (tr) {
                tr->last_rc = rc;
                tr->last_qid = qid;
        }
        trace_s390_zcrypt_rep(xcRB, func_code, rc,
                              AP_QID_CARD(qid), AP_QID_QUEUE(qid));
        return rc;
}

long zcrypt_send_cprb(struct ica_xcRB *xcRB)
{
        return _zcrypt_send_cprb(false, &ap_perms, NULL, xcRB);
}
EXPORT_SYMBOL(zcrypt_send_cprb);

static bool is_desired_ep11_card(unsigned int dev_id,
                                 unsigned short target_num,
                                 struct ep11_target_dev *targets)
{
        while (target_num-- > 0) {
                if (targets->ap_id == dev_id || targets->ap_id == AUTOSEL_AP)
                        return true;
                targets++;
        }
        return false;
}

static bool is_desired_ep11_queue(unsigned int dev_qid,
                                  unsigned short target_num,
                                  struct ep11_target_dev *targets)
{
        int card = AP_QID_CARD(dev_qid), dom = AP_QID_QUEUE(dev_qid);

        while (target_num-- > 0) {
                if ((targets->ap_id == card || targets->ap_id == AUTOSEL_AP) &&
                    (targets->dom_id == dom || targets->dom_id == AUTOSEL_DOM))
                        return true;
                targets++;
        }
        return false;
}

static long _zcrypt_send_ep11_cprb(bool userspace, struct ap_perms *perms,
                                   struct zcrypt_track *tr,
                                   struct ep11_urb *xcrb)
{
        struct zcrypt_card *zc, *pref_zc;
        struct zcrypt_queue *zq, *pref_zq;
        struct ep11_target_dev *targets;
        unsigned short target_num;
        unsigned int wgt = 0, pref_wgt = 0;
        unsigned int func_code;
        struct ap_message ap_msg;
        int cpen, qpen, qid = 0, rc = -ENODEV;
        struct module *mod;

        trace_s390_zcrypt_req(xcrb, TP_ZSENDEP11CPRB);

        ap_init_message(&ap_msg);

#ifdef CONFIG_ZCRYPT_DEBUG
        if (tr && tr->fi.cmd)
                ap_msg.fi.cmd = tr->fi.cmd;
#endif

        target_num = (unsigned short) xcrb->targets_num;

        /* empty list indicates autoselect (all available targets) */
        targets = NULL;
        if (target_num != 0) {
                struct ep11_target_dev __user *uptr;

                targets = kcalloc(target_num, sizeof(*targets), GFP_KERNEL);
                if (!targets) {
                        func_code = 0;
                        rc = -ENOMEM;
                        goto out;
                }

                uptr = (struct ep11_target_dev __force __user *) xcrb->targets;
                if (z_copy_from_user(userspace, targets, uptr,
                                   target_num * sizeof(*targets))) {
                        func_code = 0;
                        rc = -EFAULT;
                        goto out_free;
                }
        }

        rc = get_ep11cprb_fc(userspace, xcrb, &ap_msg, &func_code);
        if (rc)
                goto out_free;

        pref_zc = NULL;
        pref_zq = NULL;
        spin_lock(&zcrypt_list_lock);
        for_each_zcrypt_card(zc) {
                /* Check for useable EP11 card */
                if (!zc->online || !zc->card->config ||
                    !(zc->card->functions & 0x04000000))
                        continue;
                /* Check for user selected EP11 card */
                if (targets &&
                    !is_desired_ep11_card(zc->card->id, target_num, targets))
                        continue;
                /* check if request size exceeds card max msg size */
                if (ap_msg.len > zc->card->maxmsgsize)
                        continue;
                /* check if device node has admission for this card */
                if (!zcrypt_check_card(perms, zc->card->id))
                        continue;
                /* get weight index of the card device  */
                wgt = speed_idx_ep11(func_code) * zc->speed_rating[SECKEY];
                /* penalty if this msg was previously sent via this card */
                cpen = (tr && tr->again_counter && tr->last_qid &&
                        AP_QID_CARD(tr->last_qid) == zc->card->id) ?
                        TRACK_AGAIN_CARD_WEIGHT_PENALTY : 0;
                if (!zcrypt_card_compare(zc, pref_zc, wgt + cpen, pref_wgt))
                        continue;
                for_each_zcrypt_queue(zq, zc) {
                        /* check if device is useable and eligible */
                        if (!zq->online ||
                            !zq->ops->send_ep11_cprb ||
                            !zq->queue->config ||
                            (targets &&
                             !is_desired_ep11_queue(zq->queue->qid,
                                                    target_num, targets)))
                                continue;
                        /* check if device node has admission for this queue */
                        if (!zcrypt_check_queue(perms,
                                                AP_QID_QUEUE(zq->queue->qid)))
                                continue;
                        /* penalty if the msg was previously sent at this qid */
                        qpen = (tr && tr->again_counter && tr->last_qid &&
                                tr->last_qid == zq->queue->qid) ?
                                TRACK_AGAIN_QUEUE_WEIGHT_PENALTY : 0;
                        if (!zcrypt_queue_compare(zq, pref_zq,
                                                  wgt + cpen + qpen, pref_wgt))
                                continue;
                        pref_zc = zc;
                        pref_zq = zq;
                        pref_wgt = wgt + cpen + qpen;
                }
        }
        pref_zq = zcrypt_pick_queue(pref_zc, pref_zq, &mod, wgt);
        spin_unlock(&zcrypt_list_lock);

        if (!pref_zq) {
                rc = -ENODEV;
                goto out_free;
        }

        qid = pref_zq->queue->qid;
        rc = pref_zq->ops->send_ep11_cprb(userspace, pref_zq, xcrb, &ap_msg);

        spin_lock(&zcrypt_list_lock);
        zcrypt_drop_queue(pref_zc, pref_zq, mod, wgt);
        spin_unlock(&zcrypt_list_lock);

out_free:
        kfree(targets);
out:
        ap_release_message(&ap_msg);
        if (tr) {
                tr->last_rc = rc;
                tr->last_qid = qid;
        }
        trace_s390_zcrypt_rep(xcrb, func_code, rc,
                              AP_QID_CARD(qid), AP_QID_QUEUE(qid));
        return rc;
}

long zcrypt_send_ep11_cprb(struct ep11_urb *xcrb)
{
        return _zcrypt_send_ep11_cprb(false, &ap_perms, NULL, xcrb);
}
EXPORT_SYMBOL(zcrypt_send_ep11_cprb);

static long zcrypt_rng(char *buffer)
{
        struct zcrypt_card *zc, *pref_zc;
        struct zcrypt_queue *zq, *pref_zq;
        unsigned int wgt = 0, pref_wgt = 0;
        unsigned int func_code;
        struct ap_message ap_msg;
        unsigned int domain;
        int qid = 0, rc = -ENODEV;
        struct module *mod;

        trace_s390_zcrypt_req(buffer, TP_HWRNGCPRB);

        ap_init_message(&ap_msg);
        rc = get_rng_fc(&ap_msg, &func_code, &domain);
        if (rc)
                goto out;

        pref_zc = NULL;
        pref_zq = NULL;
        spin_lock(&zcrypt_list_lock);
        for_each_zcrypt_card(zc) {
                /* Check for useable CCA card */
                if (!zc->online || !zc->card->config ||
                    !(zc->card->functions & 0x10000000))
                        continue;
                /* get weight index of the card device  */
                wgt = zc->speed_rating[func_code];
                if (!zcrypt_card_compare(zc, pref_zc, wgt, pref_wgt))
                        continue;
                for_each_zcrypt_queue(zq, zc) {
                        /* check if device is useable and eligible */
                        if (!zq->online || !zq->ops->rng ||
                            !zq->queue->config)
                                continue;
                        if (!zcrypt_queue_compare(zq, pref_zq, wgt, pref_wgt))
                                continue;
                        pref_zc = zc;
                        pref_zq = zq;
                        pref_wgt = wgt;
                }
        }
        pref_zq = zcrypt_pick_queue(pref_zc, pref_zq, &mod, wgt);
        spin_unlock(&zcrypt_list_lock);

        if (!pref_zq) {
                rc = -ENODEV;
                goto out;
        }

        qid = pref_zq->queue->qid;
        rc = pref_zq->ops->rng(pref_zq, buffer, &ap_msg);

        spin_lock(&zcrypt_list_lock);
        zcrypt_drop_queue(pref_zc, pref_zq, mod, wgt);
        spin_unlock(&zcrypt_list_lock);

out:
        ap_release_message(&ap_msg);
        trace_s390_zcrypt_rep(buffer, func_code, rc,
                              AP_QID_CARD(qid), AP_QID_QUEUE(qid));
        return rc;
}

static void zcrypt_device_status_mask(struct zcrypt_device_status *devstatus)
{
        struct zcrypt_card *zc;
        struct zcrypt_queue *zq;
        struct zcrypt_device_status *stat;
        int card, queue;

        memset(devstatus, 0, MAX_ZDEV_ENTRIES
               * sizeof(struct zcrypt_device_status));

        spin_lock(&zcrypt_list_lock);
        for_each_zcrypt_card(zc) {
                for_each_zcrypt_queue(zq, zc) {
                        card = AP_QID_CARD(zq->queue->qid);
                        if (card >= MAX_ZDEV_CARDIDS)
                                continue;
                        queue = AP_QID_QUEUE(zq->queue->qid);
                        stat = &devstatus[card * AP_DOMAINS + queue];
                        stat->hwtype = zc->card->ap_dev.device_type;
                        stat->functions = zc->card->functions >> 26;
                        stat->qid = zq->queue->qid;
                        stat->online = zq->online ? 0x01 : 0x00;
                }
        }
        spin_unlock(&zcrypt_list_lock);
}

void zcrypt_device_status_mask_ext(struct zcrypt_device_status_ext *devstatus)
{
        struct zcrypt_card *zc;
        struct zcrypt_queue *zq;
        struct zcrypt_device_status_ext *stat;
        int card, queue;

        memset(devstatus, 0, MAX_ZDEV_ENTRIES_EXT
               * sizeof(struct zcrypt_device_status_ext));

        spin_lock(&zcrypt_list_lock);
        for_each_zcrypt_card(zc) {
                for_each_zcrypt_queue(zq, zc) {
                        card = AP_QID_CARD(zq->queue->qid);
                        queue = AP_QID_QUEUE(zq->queue->qid);
                        stat = &devstatus[card * AP_DOMAINS + queue];
                        stat->hwtype = zc->card->ap_dev.device_type;
                        stat->functions = zc->card->functions >> 26;
                        stat->qid = zq->queue->qid;
                        stat->online = zq->online ? 0x01 : 0x00;
                }
        }
        spin_unlock(&zcrypt_list_lock);
}
EXPORT_SYMBOL(zcrypt_device_status_mask_ext);

int zcrypt_device_status_ext(int card, int queue,
                             struct zcrypt_device_status_ext *devstat)
{
        struct zcrypt_card *zc;
        struct zcrypt_queue *zq;

        memset(devstat, 0, sizeof(*devstat));

        spin_lock(&zcrypt_list_lock);
        for_each_zcrypt_card(zc) {
                for_each_zcrypt_queue(zq, zc) {
                        if (card == AP_QID_CARD(zq->queue->qid) &&
                            queue == AP_QID_QUEUE(zq->queue->qid)) {
                                devstat->hwtype = zc->card->ap_dev.device_type;
                                devstat->functions = zc->card->functions >> 26;
                                devstat->qid = zq->queue->qid;
                                devstat->online = zq->online ? 0x01 : 0x00;
                                spin_unlock(&zcrypt_list_lock);
                                return 0;
                        }
                }
        }
        spin_unlock(&zcrypt_list_lock);

        return -ENODEV;
}
EXPORT_SYMBOL(zcrypt_device_status_ext);

static void zcrypt_status_mask(char status[], size_t max_adapters)
{
        struct zcrypt_card *zc;
        struct zcrypt_queue *zq;
        int card;

        memset(status, 0, max_adapters);
        spin_lock(&zcrypt_list_lock);
        for_each_zcrypt_card(zc) {
                for_each_zcrypt_queue(zq, zc) {
                        card = AP_QID_CARD(zq->queue->qid);
                        if (AP_QID_QUEUE(zq->queue->qid) != ap_domain_index
                            || card >= max_adapters)
                                continue;
                        status[card] = zc->online ? zc->user_space_type : 0x0d;
                }
        }
        spin_unlock(&zcrypt_list_lock);
}

static void zcrypt_qdepth_mask(char qdepth[], size_t max_adapters)
{
        struct zcrypt_card *zc;
        struct zcrypt_queue *zq;
        int card;

        memset(qdepth, 0, max_adapters);
        spin_lock(&zcrypt_list_lock);
        local_bh_disable();
        for_each_zcrypt_card(zc) {
                for_each_zcrypt_queue(zq, zc) {
                        card = AP_QID_CARD(zq->queue->qid);
                        if (AP_QID_QUEUE(zq->queue->qid) != ap_domain_index
                            || card >= max_adapters)
                                continue;
                        spin_lock(&zq->queue->lock);
                        qdepth[card] =
                                zq->queue->pendingq_count +
                                zq->queue->requestq_count;
                        spin_unlock(&zq->queue->lock);
                }
        }
        local_bh_enable();
        spin_unlock(&zcrypt_list_lock);
}

static void zcrypt_perdev_reqcnt(u32 reqcnt[], size_t max_adapters)
{
        struct zcrypt_card *zc;
        struct zcrypt_queue *zq;
        int card;
        u64 cnt;

        memset(reqcnt, 0, sizeof(int) * max_adapters);
        spin_lock(&zcrypt_list_lock);
        local_bh_disable();
        for_each_zcrypt_card(zc) {
                for_each_zcrypt_queue(zq, zc) {
                        card = AP_QID_CARD(zq->queue->qid);
                        if (AP_QID_QUEUE(zq->queue->qid) != ap_domain_index
                            || card >= max_adapters)
                                continue;
                        spin_lock(&zq->queue->lock);
                        cnt = zq->queue->total_request_count;
                        spin_unlock(&zq->queue->lock);
                        reqcnt[card] = (cnt < UINT_MAX) ? (u32) cnt : UINT_MAX;
                }
        }
        local_bh_enable();
        spin_unlock(&zcrypt_list_lock);
}

static int zcrypt_pendingq_count(void)
{
        struct zcrypt_card *zc;
        struct zcrypt_queue *zq;
        int pendingq_count;

        pendingq_count = 0;
        spin_lock(&zcrypt_list_lock);
        local_bh_disable();
        for_each_zcrypt_card(zc) {
                for_each_zcrypt_queue(zq, zc) {
                        if (AP_QID_QUEUE(zq->queue->qid) != ap_domain_index)
                                continue;
                        spin_lock(&zq->queue->lock);
                        pendingq_count += zq->queue->pendingq_count;
                        spin_unlock(&zq->queue->lock);
                }
        }
        local_bh_enable();
        spin_unlock(&zcrypt_list_lock);
        return pendingq_count;
}

static int zcrypt_requestq_count(void)
{
        struct zcrypt_card *zc;
        struct zcrypt_queue *zq;
        int requestq_count;

        requestq_count = 0;
        spin_lock(&zcrypt_list_lock);
        local_bh_disable();
        for_each_zcrypt_card(zc) {
                for_each_zcrypt_queue(zq, zc) {
                        if (AP_QID_QUEUE(zq->queue->qid) != ap_domain_index)
                                continue;
                        spin_lock(&zq->queue->lock);
                        requestq_count += zq->queue->requestq_count;
                        spin_unlock(&zq->queue->lock);
                }
        }
        local_bh_enable();
        spin_unlock(&zcrypt_list_lock);
        return requestq_count;
}

static int icarsamodexpo_ioctl(struct ap_perms *perms, unsigned long arg)
{
        int rc;
        struct zcrypt_track tr;
        struct ica_rsa_modexpo mex;
        struct ica_rsa_modexpo __user *umex = (void __user *) arg;

        memset(&tr, 0, sizeof(tr));
        if (copy_from_user(&mex, umex, sizeof(mex)))
                return -EFAULT;

#ifdef CONFIG_ZCRYPT_DEBUG
        if (mex.inputdatalength & (1U << 31)) {
                if (!capable(CAP_SYS_ADMIN))
                        return -EPERM;
                tr.fi.cmd = (u16)(mex.inputdatalength >> 16);
        }
        mex.inputdatalength &= 0x0000FFFF;
#endif

        do {
                rc = zcrypt_rsa_modexpo(perms, &tr, &mex);
                if (rc == -EAGAIN)
                        tr.again_counter++;
#ifdef CONFIG_ZCRYPT_DEBUG
                if (rc == -EAGAIN && (tr.fi.flags & AP_FI_FLAG_NO_RETRY))
                        break;
#endif
        } while (rc == -EAGAIN && tr.again_counter < TRACK_AGAIN_MAX);
        /* on failure: retry once again after a requested rescan */
        if ((rc == -ENODEV) && (zcrypt_process_rescan()))
                do {
                        rc = zcrypt_rsa_modexpo(perms, &tr, &mex);
                        if (rc == -EAGAIN)
                                tr.again_counter++;
                } while (rc == -EAGAIN && tr.again_counter < TRACK_AGAIN_MAX);
        if (rc == -EAGAIN && tr.again_counter >= TRACK_AGAIN_MAX)
                rc = -EIO;
        if (rc) {
                ZCRYPT_DBF_DBG("ioctl ICARSAMODEXPO rc=%d\n", rc);
                return rc;
        }
        return put_user(mex.outputdatalength, &umex->outputdatalength);
}

static int icarsacrt_ioctl(struct ap_perms *perms, unsigned long arg)
{
        int rc;
        struct zcrypt_track tr;
        struct ica_rsa_modexpo_crt crt;
        struct ica_rsa_modexpo_crt __user *ucrt = (void __user *) arg;

        memset(&tr, 0, sizeof(tr));
        if (copy_from_user(&crt, ucrt, sizeof(crt)))
                return -EFAULT;

#ifdef CONFIG_ZCRYPT_DEBUG
        if (crt.inputdatalength & (1U << 31)) {
                if (!capable(CAP_SYS_ADMIN))
                        return -EPERM;
                tr.fi.cmd = (u16)(crt.inputdatalength >> 16);
        }
        crt.inputdatalength &= 0x0000FFFF;
#endif

        do {
                rc = zcrypt_rsa_crt(perms, &tr, &crt);
                if (rc == -EAGAIN)
                        tr.again_counter++;
#ifdef CONFIG_ZCRYPT_DEBUG
                if (rc == -EAGAIN && (tr.fi.flags & AP_FI_FLAG_NO_RETRY))
                        break;
#endif
        } while (rc == -EAGAIN && tr.again_counter < TRACK_AGAIN_MAX);
        /* on failure: retry once again after a requested rescan */
        if ((rc == -ENODEV) && (zcrypt_process_rescan()))
                do {
                        rc = zcrypt_rsa_crt(perms, &tr, &crt);
                        if (rc == -EAGAIN)
                                tr.again_counter++;
                } while (rc == -EAGAIN && tr.again_counter < TRACK_AGAIN_MAX);
        if (rc == -EAGAIN && tr.again_counter >= TRACK_AGAIN_MAX)
                rc = -EIO;
        if (rc) {
                ZCRYPT_DBF_DBG("ioctl ICARSACRT rc=%d\n", rc);
                return rc;
        }
        return put_user(crt.outputdatalength, &ucrt->outputdatalength);
}

static int zsecsendcprb_ioctl(struct ap_perms *perms, unsigned long arg)
{
        int rc;
        struct ica_xcRB xcRB;
        struct zcrypt_track tr;
        struct ica_xcRB __user *uxcRB = (void __user *) arg;

        memset(&tr, 0, sizeof(tr));
        if (copy_from_user(&xcRB, uxcRB, sizeof(xcRB)))
                return -EFAULT;

#ifdef CONFIG_ZCRYPT_DEBUG
        if ((xcRB.status & 0x8000FFFF) == 0x80004649 /* 'FI' */) {
                if (!capable(CAP_SYS_ADMIN))
                        return -EPERM;
                tr.fi.cmd = (u16)(xcRB.status >> 16);
        }
        xcRB.status = 0;
#endif

        do {
                rc = _zcrypt_send_cprb(true, perms, &tr, &xcRB);
                if (rc == -EAGAIN)
                        tr.again_counter++;
#ifdef CONFIG_ZCRYPT_DEBUG
                if (rc == -EAGAIN && (tr.fi.flags & AP_FI_FLAG_NO_RETRY))
                        break;
#endif
        } while (rc == -EAGAIN && tr.again_counter < TRACK_AGAIN_MAX);
        /* on failure: retry once again after a requested rescan */
        if ((rc == -ENODEV) && (zcrypt_process_rescan()))
                do {
                        rc = _zcrypt_send_cprb(true, perms, &tr, &xcRB);
                        if (rc == -EAGAIN)
                                tr.again_counter++;
                } while (rc == -EAGAIN && tr.again_counter < TRACK_AGAIN_MAX);
        if (rc == -EAGAIN && tr.again_counter >= TRACK_AGAIN_MAX)
                rc = -EIO;
        if (rc)
                ZCRYPT_DBF_DBG("ioctl ZSENDCPRB rc=%d status=0x%x\n",
                               rc, xcRB.status);
        if (copy_to_user(uxcRB, &xcRB, sizeof(xcRB)))
                return -EFAULT;
        return rc;
}

static int zsendep11cprb_ioctl(struct ap_perms *perms, unsigned long arg)
{
        int rc;
        struct ep11_urb xcrb;
        struct zcrypt_track tr;
        struct ep11_urb __user *uxcrb = (void __user *)arg;

        memset(&tr, 0, sizeof(tr));
        if (copy_from_user(&xcrb, uxcrb, sizeof(xcrb)))
                return -EFAULT;

#ifdef CONFIG_ZCRYPT_DEBUG
        if (xcrb.req_len & (1ULL << 63)) {
                if (!capable(CAP_SYS_ADMIN))
                        return -EPERM;
                tr.fi.cmd = (u16)(xcrb.req_len >> 48);
        }
        xcrb.req_len &= 0x0000FFFFFFFFFFFFULL;
#endif

        do {
                rc = _zcrypt_send_ep11_cprb(true, perms, &tr, &xcrb);
                if (rc == -EAGAIN)
                        tr.again_counter++;
#ifdef CONFIG_ZCRYPT_DEBUG
                if (rc == -EAGAIN && (tr.fi.flags & AP_FI_FLAG_NO_RETRY))
                        break;
#endif
        } while (rc == -EAGAIN && tr.again_counter < TRACK_AGAIN_MAX);
        /* on failure: retry once again after a requested rescan */
        if ((rc == -ENODEV) && (zcrypt_process_rescan()))
                do {
                        rc = _zcrypt_send_ep11_cprb(true, perms, &tr, &xcrb);
                        if (rc == -EAGAIN)
                                tr.again_counter++;
                } while (rc == -EAGAIN && tr.again_counter < TRACK_AGAIN_MAX);
        if (rc == -EAGAIN && tr.again_counter >= TRACK_AGAIN_MAX)
                rc = -EIO;
        if (rc)
                ZCRYPT_DBF_DBG("ioctl ZSENDEP11CPRB rc=%d\n", rc);
        if (copy_to_user(uxcrb, &xcrb, sizeof(xcrb)))
                return -EFAULT;
        return rc;
}

static long zcrypt_unlocked_ioctl(struct file *filp, unsigned int cmd,
                                  unsigned long arg)
{
        int rc;
        struct ap_perms *perms =
                (struct ap_perms *) filp->private_data;

        rc = zcrypt_check_ioctl(perms, cmd);
        if (rc)
                return rc;

        switch (cmd) {
        case ICARSAMODEXPO:
                return icarsamodexpo_ioctl(perms, arg);
        case ICARSACRT:
                return icarsacrt_ioctl(perms, arg);
        case ZSECSENDCPRB:
                return zsecsendcprb_ioctl(perms, arg);
        case ZSENDEP11CPRB:
                return zsendep11cprb_ioctl(perms, arg);
        case ZCRYPT_DEVICE_STATUS: {
                struct zcrypt_device_status_ext *device_status;
                size_t total_size = MAX_ZDEV_ENTRIES_EXT
                        * sizeof(struct zcrypt_device_status_ext);

                device_status = kzalloc(total_size, GFP_KERNEL);
                if (!device_status)
                        return -ENOMEM;
                zcrypt_device_status_mask_ext(device_status);
                if (copy_to_user((char __user *) arg, device_status,
                                 total_size))
                        rc = -EFAULT;
                kfree(device_status);
                return rc;
        }
        case ZCRYPT_STATUS_MASK: {
                char status[AP_DEVICES];

                zcrypt_status_mask(status, AP_DEVICES);
                if (copy_to_user((char __user *) arg, status, sizeof(status)))
                        return -EFAULT;
                return 0;
        }
        case ZCRYPT_QDEPTH_MASK: {
                char qdepth[AP_DEVICES];

                zcrypt_qdepth_mask(qdepth, AP_DEVICES);
                if (copy_to_user((char __user *) arg, qdepth, sizeof(qdepth)))
                        return -EFAULT;
                return 0;
        }
        case ZCRYPT_PERDEV_REQCNT: {
                u32 *reqcnt;

                reqcnt = kcalloc(AP_DEVICES, sizeof(u32), GFP_KERNEL);
                if (!reqcnt)
                        return -ENOMEM;
                zcrypt_perdev_reqcnt(reqcnt, AP_DEVICES);
                if (copy_to_user((int __user *) arg, reqcnt,
                                 sizeof(u32) * AP_DEVICES))
                        rc = -EFAULT;
                kfree(reqcnt);
                return rc;
        }
        case Z90STAT_REQUESTQ_COUNT:
                return put_user(zcrypt_requestq_count(), (int __user *) arg);
        case Z90STAT_PENDINGQ_COUNT:
                return put_user(zcrypt_pendingq_count(), (int __user *) arg);
        case Z90STAT_TOTALOPEN_COUNT:
                return put_user(atomic_read(&zcrypt_open_count),
                                (int __user *) arg);
        case Z90STAT_DOMAIN_INDEX:
                return put_user(ap_domain_index, (int __user *) arg);
        /*
         * Deprecated ioctls
         */
        case ZDEVICESTATUS: {
                /* the old ioctl supports only 64 adapters */
                struct zcrypt_device_status *device_status;
                size_t total_size = MAX_ZDEV_ENTRIES
                        * sizeof(struct zcrypt_device_status);

                device_status = kzalloc(total_size, GFP_KERNEL);
                if (!device_status)
                        return -ENOMEM;
                zcrypt_device_status_mask(device_status);
                if (copy_to_user((char __user *) arg, device_status,
                                 total_size))
                        rc = -EFAULT;
                kfree(device_status);
                return rc;
        }
        case Z90STAT_STATUS_MASK: {
                /* the old ioctl supports only 64 adapters */
                char status[MAX_ZDEV_CARDIDS];

                zcrypt_status_mask(status, MAX_ZDEV_CARDIDS);
                if (copy_to_user((char __user *) arg, status, sizeof(status)))
                        return -EFAULT;
                return 0;
        }
        case Z90STAT_QDEPTH_MASK: {
                /* the old ioctl supports only 64 adapters */
                char qdepth[MAX_ZDEV_CARDIDS];

                zcrypt_qdepth_mask(qdepth, MAX_ZDEV_CARDIDS);
                if (copy_to_user((char __user *) arg, qdepth, sizeof(qdepth)))
                        return -EFAULT;
                return 0;
        }
        case Z90STAT_PERDEV_REQCNT: {
                /* the old ioctl supports only 64 adapters */
                u32 reqcnt[MAX_ZDEV_CARDIDS];

                zcrypt_perdev_reqcnt(reqcnt, MAX_ZDEV_CARDIDS);
                if (copy_to_user((int __user *) arg, reqcnt, sizeof(reqcnt)))
                        return -EFAULT;
                return 0;
        }
        /* unknown ioctl number */
        default:
                ZCRYPT_DBF_DBG("unknown ioctl 0x%08x\n", cmd);
                return -ENOIOCTLCMD;
        }
}

#ifdef CONFIG_COMPAT
/*
 * ioctl32 conversion routines
 */
struct compat_ica_rsa_modexpo {
        compat_uptr_t   inputdata;
        unsigned int    inputdatalength;
        compat_uptr_t   outputdata;
        unsigned int    outputdatalength;
        compat_uptr_t   b_key;
        compat_uptr_t   n_modulus;
};

static long trans_modexpo32(struct ap_perms *perms, struct file *filp,
                            unsigned int cmd, unsigned long arg)
{
        struct compat_ica_rsa_modexpo __user *umex32 = compat_ptr(arg);
        struct compat_ica_rsa_modexpo mex32;
        struct ica_rsa_modexpo mex64;
        struct zcrypt_track tr;
        long rc;

        memset(&tr, 0, sizeof(tr));
        if (copy_from_user(&mex32, umex32, sizeof(mex32)))
                return -EFAULT;
        mex64.inputdata = compat_ptr(mex32.inputdata);
        mex64.inputdatalength = mex32.inputdatalength;
        mex64.outputdata = compat_ptr(mex32.outputdata);
        mex64.outputdatalength = mex32.outputdatalength;
        mex64.b_key = compat_ptr(mex32.b_key);
        mex64.n_modulus = compat_ptr(mex32.n_modulus);
        do {
                rc = zcrypt_rsa_modexpo(perms, &tr, &mex64);
                if (rc == -EAGAIN)
                        tr.again_counter++;
        } while (rc == -EAGAIN && tr.again_counter < TRACK_AGAIN_MAX);
        /* on failure: retry once again after a requested rescan */
        if ((rc == -ENODEV) && (zcrypt_process_rescan()))
                do {
                        rc = zcrypt_rsa_modexpo(perms, &tr, &mex64);
                        if (rc == -EAGAIN)
                                tr.again_counter++;
                } while (rc == -EAGAIN && tr.again_counter < TRACK_AGAIN_MAX);
        if (rc == -EAGAIN && tr.again_counter >= TRACK_AGAIN_MAX)
                rc = -EIO;
        if (rc)
                return rc;
        return put_user(mex64.outputdatalength,
                        &umex32->outputdatalength);
}

struct compat_ica_rsa_modexpo_crt {
        compat_uptr_t   inputdata;
        unsigned int    inputdatalength;
        compat_uptr_t   outputdata;
        unsigned int    outputdatalength;
        compat_uptr_t   bp_key;
        compat_uptr_t   bq_key;
        compat_uptr_t   np_prime;
        compat_uptr_t   nq_prime;
        compat_uptr_t   u_mult_inv;
};

static long trans_modexpo_crt32(struct ap_perms *perms, struct file *filp,
                                unsigned int cmd, unsigned long arg)
{
        struct compat_ica_rsa_modexpo_crt __user *ucrt32 = compat_ptr(arg);
        struct compat_ica_rsa_modexpo_crt crt32;
        struct ica_rsa_modexpo_crt crt64;
        struct zcrypt_track tr;
        long rc;

        memset(&tr, 0, sizeof(tr));
        if (copy_from_user(&crt32, ucrt32, sizeof(crt32)))
                return -EFAULT;
        crt64.inputdata = compat_ptr(crt32.inputdata);
        crt64.inputdatalength = crt32.inputdatalength;
        crt64.outputdata = compat_ptr(crt32.outputdata);
        crt64.outputdatalength = crt32.outputdatalength;
        crt64.bp_key = compat_ptr(crt32.bp_key);
        crt64.bq_key = compat_ptr(crt32.bq_key);
        crt64.np_prime = compat_ptr(crt32.np_prime);
        crt64.nq_prime = compat_ptr(crt32.nq_prime);
        crt64.u_mult_inv = compat_ptr(crt32.u_mult_inv);
        do {
                rc = zcrypt_rsa_crt(perms, &tr, &crt64);
                if (rc == -EAGAIN)
                        tr.again_counter++;
        } while (rc == -EAGAIN && tr.again_counter < TRACK_AGAIN_MAX);
        /* on failure: retry once again after a requested rescan */
        if ((rc == -ENODEV) && (zcrypt_process_rescan()))
                do {
                        rc = zcrypt_rsa_crt(perms, &tr, &crt64);
                        if (rc == -EAGAIN)
                                tr.again_counter++;
                } while (rc == -EAGAIN && tr.again_counter < TRACK_AGAIN_MAX);
        if (rc == -EAGAIN && tr.again_counter >= TRACK_AGAIN_MAX)
                rc = -EIO;
        if (rc)
                return rc;
        return put_user(crt64.outputdatalength,
                        &ucrt32->outputdatalength);
}

struct compat_ica_xcRB {
        unsigned short  agent_ID;
        unsigned int    user_defined;
        unsigned short  request_ID;
        unsigned int    request_control_blk_length;
        unsigned char   padding1[16 - sizeof(compat_uptr_t)];
        compat_uptr_t   request_control_blk_addr;
        unsigned int    request_data_length;
        char            padding2[16 - sizeof(compat_uptr_t)];
        compat_uptr_t   request_data_address;
        unsigned int    reply_control_blk_length;
        char            padding3[16 - sizeof(compat_uptr_t)];
        compat_uptr_t   reply_control_blk_addr;
        unsigned int    reply_data_length;
        char            padding4[16 - sizeof(compat_uptr_t)];
        compat_uptr_t   reply_data_addr;
        unsigned short  priority_window;
        unsigned int    status;
} __packed;

static long trans_xcRB32(struct ap_perms *perms, struct file *filp,
                         unsigned int cmd, unsigned long arg)
{
        struct compat_ica_xcRB __user *uxcRB32 = compat_ptr(arg);
        struct compat_ica_xcRB xcRB32;
        struct zcrypt_track tr;
        struct ica_xcRB xcRB64;
        long rc;

        memset(&tr, 0, sizeof(tr));
        if (copy_from_user(&xcRB32, uxcRB32, sizeof(xcRB32)))
                return -EFAULT;
        xcRB64.agent_ID = xcRB32.agent_ID;
        xcRB64.user_defined = xcRB32.user_defined;
        xcRB64.request_ID = xcRB32.request_ID;
        xcRB64.request_control_blk_length =
                xcRB32.request_control_blk_length;
        xcRB64.request_control_blk_addr =
                compat_ptr(xcRB32.request_control_blk_addr);
        xcRB64.request_data_length =
                xcRB32.request_data_length;
        xcRB64.request_data_address =
                compat_ptr(xcRB32.request_data_address);
        xcRB64.reply_control_blk_length =
                xcRB32.reply_control_blk_length;
        xcRB64.reply_control_blk_addr =
                compat_ptr(xcRB32.reply_control_blk_addr);
        xcRB64.reply_data_length = xcRB32.reply_data_length;
        xcRB64.reply_data_addr =
                compat_ptr(xcRB32.reply_data_addr);
        xcRB64.priority_window = xcRB32.priority_window;
        xcRB64.status = xcRB32.status;
        do {
                rc = _zcrypt_send_cprb(true, perms, &tr, &xcRB64);
                if (rc == -EAGAIN)
                        tr.again_counter++;
        } while (rc == -EAGAIN && tr.again_counter < TRACK_AGAIN_MAX);
        /* on failure: retry once again after a requested rescan */
        if ((rc == -ENODEV) && (zcrypt_process_rescan()))
                do {
                        rc = _zcrypt_send_cprb(true, perms, &tr, &xcRB64);
                        if (rc == -EAGAIN)
                                tr.again_counter++;
                } while (rc == -EAGAIN && tr.again_counter < TRACK_AGAIN_MAX);
        if (rc == -EAGAIN && tr.again_counter >= TRACK_AGAIN_MAX)
                rc = -EIO;
        xcRB32.reply_control_blk_length = xcRB64.reply_control_blk_length;
        xcRB32.reply_data_length = xcRB64.reply_data_length;
        xcRB32.status = xcRB64.status;
        if (copy_to_user(uxcRB32, &xcRB32, sizeof(xcRB32)))
                return -EFAULT;
        return rc;
}

static long zcrypt_compat_ioctl(struct file *filp, unsigned int cmd,
                         unsigned long arg)
{
        int rc;
        struct ap_perms *perms =
                (struct ap_perms *) filp->private_data;

        rc = zcrypt_check_ioctl(perms, cmd);
        if (rc)
                return rc;

        if (cmd == ICARSAMODEXPO)
                return trans_modexpo32(perms, filp, cmd, arg);
        if (cmd == ICARSACRT)
                return trans_modexpo_crt32(perms, filp, cmd, arg);
        if (cmd == ZSECSENDCPRB)
                return trans_xcRB32(perms, filp, cmd, arg);
        return zcrypt_unlocked_ioctl(filp, cmd, arg);
}
#endif

/*
 * Misc device file operations.
 */
static const struct file_operations zcrypt_fops = {
        .owner          = THIS_MODULE,
        .read           = zcrypt_read,
        .write          = zcrypt_write,
        .unlocked_ioctl = zcrypt_unlocked_ioctl,
#ifdef CONFIG_COMPAT
        .compat_ioctl   = zcrypt_compat_ioctl,
#endif
        .open           = zcrypt_open,
        .release        = zcrypt_release,
        .llseek         = no_llseek,
};

/*
 * Misc device.
 */
static struct miscdevice zcrypt_misc_device = {
        .minor      = MISC_DYNAMIC_MINOR,
        .name       = "z90crypt",
        .fops       = &zcrypt_fops,
};

static int zcrypt_rng_device_count;
static u32 *zcrypt_rng_buffer;
static int zcrypt_rng_buffer_index;
static DEFINE_MUTEX(zcrypt_rng_mutex);

static int zcrypt_rng_data_read(struct hwrng *rng, u32 *data)
{
        int rc;

        /*
         * We don't need locking here because the RNG API guarantees serialized
         * read method calls.
         */
        if (zcrypt_rng_buffer_index == 0) {
                rc = zcrypt_rng((char *) zcrypt_rng_buffer);
                /* on failure: retry once again after a requested rescan */
                if ((rc == -ENODEV) && (zcrypt_process_rescan()))
                        rc = zcrypt_rng((char *) zcrypt_rng_buffer);
                if (rc < 0)
                        return -EIO;
                zcrypt_rng_buffer_index = rc / sizeof(*data);
        }
        *data = zcrypt_rng_buffer[--zcrypt_rng_buffer_index];
        return sizeof(*data);
}

static struct hwrng zcrypt_rng_dev = {
        .name           = "zcrypt",
        .data_read      = zcrypt_rng_data_read,
        .quality        = 990,
};

int zcrypt_rng_device_add(void)
{
        int rc = 0;

        mutex_lock(&zcrypt_rng_mutex);
        if (zcrypt_rng_device_count == 0) {
                zcrypt_rng_buffer = (u32 *) get_zeroed_page(GFP_KERNEL);
                if (!zcrypt_rng_buffer) {
                        rc = -ENOMEM;
                        goto out;
                }
                zcrypt_rng_buffer_index = 0;
                if (!zcrypt_hwrng_seed)
                        zcrypt_rng_dev.quality = 0;
                rc = hwrng_register(&zcrypt_rng_dev);
                if (rc)
                        goto out_free;
                zcrypt_rng_device_count = 1;
        } else
                zcrypt_rng_device_count++;
        mutex_unlock(&zcrypt_rng_mutex);
        return 0;

out_free:
        free_page((unsigned long) zcrypt_rng_buffer);
out:
        mutex_unlock(&zcrypt_rng_mutex);
        return rc;
}

void zcrypt_rng_device_remove(void)
{
        mutex_lock(&zcrypt_rng_mutex);
        zcrypt_rng_device_count--;
        if (zcrypt_rng_device_count == 0) {
                hwrng_unregister(&zcrypt_rng_dev);
                free_page((unsigned long) zcrypt_rng_buffer);
        }
        mutex_unlock(&zcrypt_rng_mutex);
}

/*
 * Wait until the zcrypt api is operational.
 * The AP bus scan and the binding of ap devices to device drivers is
 * an asynchronous job. This function waits until these initial jobs
 * are done and so the zcrypt api should be ready to serve crypto
 * requests - if there are resources available. The function uses an
 * internal timeout of 60s. The very first caller will either wait for
 * ap bus bindings complete or the timeout happens. This state will be
 * remembered for further callers which will only be blocked until a
 * decision is made (timeout or bindings complete).
 * On timeout -ETIME is returned, on success the return value is 0.
 */
int zcrypt_wait_api_operational(void)
{
        static DEFINE_MUTEX(zcrypt_wait_api_lock);
        static int zcrypt_wait_api_state;
        int rc;

        rc = mutex_lock_interruptible(&zcrypt_wait_api_lock);
        if (rc)
                return rc;

        switch (zcrypt_wait_api_state) {
        case 0:
                /* initial state, invoke wait for the ap bus complete */
                rc = ap_wait_init_apqn_bindings_complete(
                        msecs_to_jiffies(60 * 1000));
                switch (rc) {
                case 0:
                        /* ap bus bindings are complete */
                        zcrypt_wait_api_state = 1;
                        break;
                case -EINTR:
                        /* interrupted, go back to caller */
                        break;
                case -ETIME:
                        /* timeout */
                        ZCRYPT_DBF_WARN("%s ap_wait_init_apqn_bindings_complete()=ETIME\n",
                                        __func__);
                        zcrypt_wait_api_state = -ETIME;
                        break;
                default:
                        /* other failure */
                        ZCRYPT_DBF_DBG("%s ap_wait_init_apqn_bindings_complete()=%d\n",
                                       __func__, rc);
                        break;
                }
                break;
        case 1:
                /* a previous caller already found ap bus bindings complete */
                rc = 0;
                break;
        default:
                /* a previous caller had timeout or other failure */
                rc = zcrypt_wait_api_state;
                break;
        }

        mutex_unlock(&zcrypt_wait_api_lock);

        return rc;
}
EXPORT_SYMBOL(zcrypt_wait_api_operational);

int __init zcrypt_debug_init(void)
{
        zcrypt_dbf_info = debug_register("zcrypt", 2, 1,
                                         DBF_MAX_SPRINTF_ARGS * sizeof(long));
        debug_register_view(zcrypt_dbf_info, &debug_sprintf_view);
        debug_set_level(zcrypt_dbf_info, DBF_ERR);

        return 0;
}

void zcrypt_debug_exit(void)
{
        debug_unregister(zcrypt_dbf_info);
}

#ifdef CONFIG_ZCRYPT_MULTIDEVNODES

static int __init zcdn_init(void)
{
        int rc;

        /* create a new class 'zcrypt' */
        zcrypt_class = class_create(THIS_MODULE, ZCRYPT_NAME);
        if (IS_ERR(zcrypt_class)) {
                rc = PTR_ERR(zcrypt_class);
                goto out_class_create_failed;
        }
        zcrypt_class->dev_release = zcdn_device_release;

        /* alloc device minor range */
        rc = alloc_chrdev_region(&zcrypt_devt,
                                 0, ZCRYPT_MAX_MINOR_NODES,
                                 ZCRYPT_NAME);
        if (rc)
                goto out_alloc_chrdev_failed;

        cdev_init(&zcrypt_cdev, &zcrypt_fops);
        zcrypt_cdev.owner = THIS_MODULE;
        rc = cdev_add(&zcrypt_cdev, zcrypt_devt, ZCRYPT_MAX_MINOR_NODES);
        if (rc)
                goto out_cdev_add_failed;

        /* need some class specific sysfs attributes */
        rc = class_create_file(zcrypt_class, &class_attr_zcdn_create);
        if (rc)
                goto out_class_create_file_1_failed;
        rc = class_create_file(zcrypt_class, &class_attr_zcdn_destroy);
        if (rc)
                goto out_class_create_file_2_failed;

        return 0;

out_class_create_file_2_failed:
        class_remove_file(zcrypt_class, &class_attr_zcdn_create);
out_class_create_file_1_failed:
        cdev_del(&zcrypt_cdev);
out_cdev_add_failed:
        unregister_chrdev_region(zcrypt_devt, ZCRYPT_MAX_MINOR_NODES);
out_alloc_chrdev_failed:
        class_destroy(zcrypt_class);
out_class_create_failed:
        return rc;
}

static void zcdn_exit(void)
{
        class_remove_file(zcrypt_class, &class_attr_zcdn_create);
        class_remove_file(zcrypt_class, &class_attr_zcdn_destroy);
        zcdn_destroy_all();
        cdev_del(&zcrypt_cdev);
        unregister_chrdev_region(zcrypt_devt, ZCRYPT_MAX_MINOR_NODES);
        class_destroy(zcrypt_class);
}

#endif

/*
 * zcrypt_api_init(): Module initialization.
 *
 * The module initialization code.
 */
int __init zcrypt_api_init(void)
{
        int rc;

        rc = zcrypt_debug_init();
        if (rc)
                goto out;

#ifdef CONFIG_ZCRYPT_MULTIDEVNODES
        rc = zcdn_init();
        if (rc)
                goto out;
#endif

        /* Register the request sprayer. */
        rc = misc_register(&zcrypt_misc_device);
        if (rc < 0)
                goto out_misc_register_failed;

        zcrypt_msgtype6_init();
        zcrypt_msgtype50_init();

        return 0;

out_misc_register_failed:
#ifdef CONFIG_ZCRYPT_MULTIDEVNODES
        zcdn_exit();
#endif
        zcrypt_debug_exit();
out:
        return rc;
}

/*
 * zcrypt_api_exit(): Module termination.
 *
 * The module termination code.
 */
void __exit zcrypt_api_exit(void)
{
#ifdef CONFIG_ZCRYPT_MULTIDEVNODES
        zcdn_exit();
#endif
        misc_deregister(&zcrypt_misc_device);
        zcrypt_msgtype6_exit();
        zcrypt_msgtype50_exit();
        zcrypt_ccamisc_exit();
        zcrypt_ep11misc_exit();
        zcrypt_debug_exit();
}

module_init(zcrypt_api_init);
module_exit(zcrypt_api_exit);