zcrypt_api.c

Go to the documentation of this file.

/*
 *  zcrypt 2.1.0
 *
 *  Copyright IBM Corp. 2001, 2012
 *  Author(s): Robert Burroughs
 *         Eric Rossman ([email protected])
 *         Cornelia Huck <[email protected]>
 *
 *  Hotplug & misc device support: Jochen Roehrig ([email protected])
 *  Major cleanup & driver split: Martin Schwidefsky <[email protected]>
 *                Ralph Wuerthner <[email protected]>
 *  MSGTYPE restruct:         Holger Dengler <[email protected]>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

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

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

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

static DEFINE_SPINLOCK(zcrypt_device_lock);
static LIST_HEAD(zcrypt_device_list);
static int zcrypt_device_count = 0;
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 int zcrypt_rng_device_add(void);
static void zcrypt_rng_device_remove(void);

static DEFINE_SPINLOCK(zcrypt_ops_list_lock);
static LIST_HEAD(zcrypt_ops_list);

static debug_info_t *zcrypt_dbf_common;
static debug_info_t *zcrypt_dbf_devices;
static struct dentry *debugfs_root;

/*
 * Device attributes common for all crypto devices.
 */
static ssize_t zcrypt_type_show(struct device *dev,
                struct device_attribute *attr, char *buf)
{
    struct zcrypt_device *zdev = to_ap_dev(dev)->private;
    return snprintf(buf, PAGE_SIZE, "%s\n", zdev->type_string);
}

static DEVICE_ATTR(type, 0444, zcrypt_type_show, NULL);

static ssize_t zcrypt_online_show(struct device *dev,
                  struct device_attribute *attr, char *buf)
{
    struct zcrypt_device *zdev = to_ap_dev(dev)->private;
    return snprintf(buf, PAGE_SIZE, "%d\n", zdev->online);
}

static ssize_t zcrypt_online_store(struct device *dev,
                   struct device_attribute *attr,
                   const char *buf, size_t count)
{
    struct zcrypt_device *zdev = to_ap_dev(dev)->private;
    int online;

    if (sscanf(buf, "%d\n", &online) != 1 || online < 0 || online > 1)
        return -EINVAL;
    zdev->online = online;
    ZCRYPT_DBF_DEV(DBF_INFO, zdev, "dev%04xo%dman", zdev->ap_dev->qid,
               zdev->online);
    if (!online)
        ap_flush_queue(zdev->ap_dev);
    return count;
}

static DEVICE_ATTR(online, 0644, zcrypt_online_show, zcrypt_online_store);

static struct attribute * zcrypt_device_attrs[] = {
    &dev_attr_type.attr,
    &dev_attr_online.attr,
    NULL,
};

static struct attribute_group zcrypt_device_attr_group = {
    .attrs = zcrypt_device_attrs,
};

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_COMMON(DBF_INFO, "rescan%07d",
                  atomic_inc_return(&zcrypt_rescan_count));
        return 1;
    }
    return 0;
}

static void __zcrypt_increase_preference(struct zcrypt_device *zdev)
{
    struct zcrypt_device *tmp;
    struct list_head *l;

    if (zdev->speed_rating == 0)
        return;
    for (l = zdev->list.prev; l != &zcrypt_device_list; l = l->prev) {
        tmp = list_entry(l, struct zcrypt_device, list);
        if ((tmp->request_count + 1) * tmp->speed_rating <=
            (zdev->request_count + 1) * zdev->speed_rating &&
            tmp->speed_rating != 0)
            break;
    }
    if (l == zdev->list.prev)
        return;
    /* Move zdev behind l */
    list_move(&zdev->list, l);
}

static void __zcrypt_decrease_preference(struct zcrypt_device *zdev)
{
    struct zcrypt_device *tmp;
    struct list_head *l;

    if (zdev->speed_rating == 0)
        return;
    for (l = zdev->list.next; l != &zcrypt_device_list; l = l->next) {
        tmp = list_entry(l, struct zcrypt_device, list);
        if ((tmp->request_count + 1) * tmp->speed_rating >
            (zdev->request_count + 1) * zdev->speed_rating ||
            tmp->speed_rating == 0)
            break;
    }
    if (l == zdev->list.next)
        return;
    /* Move zdev before l */
    list_move_tail(&zdev->list, l);
}

static void zcrypt_device_release(struct kref *kref)
{
    struct zcrypt_device *zdev =
        container_of(kref, struct zcrypt_device, refcount);
    zcrypt_device_free(zdev);
}

void zcrypt_device_get(struct zcrypt_device *zdev)
{
    kref_get(&zdev->refcount);
}
EXPORT_SYMBOL(zcrypt_device_get);

int zcrypt_device_put(struct zcrypt_device *zdev)
{
    return kref_put(&zdev->refcount, zcrypt_device_release);
}
EXPORT_SYMBOL(zcrypt_device_put);

struct zcrypt_device *zcrypt_device_alloc(size_t max_response_size)
{
    struct zcrypt_device *zdev;

    zdev = kzalloc(sizeof(struct zcrypt_device), GFP_KERNEL);
    if (!zdev)
        return NULL;
    zdev->reply.message = kmalloc(max_response_size, GFP_KERNEL);
    if (!zdev->reply.message)
        goto out_free;
    zdev->reply.length = max_response_size;
    spin_lock_init(&zdev->lock);
    INIT_LIST_HEAD(&zdev->list);
    zdev->dbf_area = zcrypt_dbf_devices;
    return zdev;

out_free:
    kfree(zdev);
    return NULL;
}
EXPORT_SYMBOL(zcrypt_device_alloc);

void zcrypt_device_free(struct zcrypt_device *zdev)
{
    kfree(zdev->reply.message);
    kfree(zdev);
}
EXPORT_SYMBOL(zcrypt_device_free);

int zcrypt_device_register(struct zcrypt_device *zdev)
{
    int rc;

    if (!zdev->ops)
        return -ENODEV;
    rc = sysfs_create_group(&zdev->ap_dev->device.kobj,
                &zcrypt_device_attr_group);
    if (rc)
        goto out;
    get_device(&zdev->ap_dev->device);
    kref_init(&zdev->refcount);
    spin_lock_bh(&zcrypt_device_lock);
    zdev->online = 1;   /* New devices are online by default. */
    ZCRYPT_DBF_DEV(DBF_INFO, zdev, "dev%04xo%dreg", zdev->ap_dev->qid,
               zdev->online);
    list_add_tail(&zdev->list, &zcrypt_device_list);
    __zcrypt_increase_preference(zdev);
    zcrypt_device_count++;
    spin_unlock_bh(&zcrypt_device_lock);
    if (zdev->ops->rng) {
        rc = zcrypt_rng_device_add();
        if (rc)
            goto out_unregister;
    }
    return 0;

out_unregister:
    spin_lock_bh(&zcrypt_device_lock);
    zcrypt_device_count--;
    list_del_init(&zdev->list);
    spin_unlock_bh(&zcrypt_device_lock);
    sysfs_remove_group(&zdev->ap_dev->device.kobj,
               &zcrypt_device_attr_group);
    put_device(&zdev->ap_dev->device);
    zcrypt_device_put(zdev);
out:
    return rc;
}
EXPORT_SYMBOL(zcrypt_device_register);

void zcrypt_device_unregister(struct zcrypt_device *zdev)
{
    if (zdev->ops->rng)
        zcrypt_rng_device_remove();
    spin_lock_bh(&zcrypt_device_lock);
    zcrypt_device_count--;
    list_del_init(&zdev->list);
    spin_unlock_bh(&zcrypt_device_lock);
    sysfs_remove_group(&zdev->ap_dev->device.kobj,
               &zcrypt_device_attr_group);
    put_device(&zdev->ap_dev->device);
    zcrypt_device_put(zdev);
}
EXPORT_SYMBOL(zcrypt_device_unregister);

void zcrypt_msgtype_register(struct zcrypt_ops *zops)
{
    if (zops->owner) {
        spin_lock_bh(&zcrypt_ops_list_lock);
        list_add_tail(&zops->list, &zcrypt_ops_list);
        spin_unlock_bh(&zcrypt_ops_list_lock);
    }
}
EXPORT_SYMBOL(zcrypt_msgtype_register);

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

static inline
struct zcrypt_ops *__ops_lookup(unsigned char *name, int variant)
{
    struct zcrypt_ops *zops;
    int found = 0;

    spin_lock_bh(&zcrypt_ops_list_lock);
    list_for_each_entry(zops, &zcrypt_ops_list, list) {
        if ((zops->variant == variant) &&
            (!strncmp(zops->owner->name, name, MODULE_NAME_LEN))) {
            found = 1;
            break;
        }
    }
    spin_unlock_bh(&zcrypt_ops_list_lock);

    if (!found)
        return NULL;
    return zops;
}

struct zcrypt_ops *zcrypt_msgtype_request(unsigned char *name, int variant)
{
    struct zcrypt_ops *zops = NULL;

    zops = __ops_lookup(name, variant);
    if (!zops) {
        request_module(name);
        zops = __ops_lookup(name, variant);
    }
    if ((!zops) || (!try_module_get(zops->owner)))
        return NULL;
    return zops;
}
EXPORT_SYMBOL(zcrypt_msgtype_request);

void zcrypt_msgtype_release(struct zcrypt_ops *zops)
{
    if (zops)
        module_put(zops->owner);
}
EXPORT_SYMBOL(zcrypt_msgtype_release);

static ssize_t zcrypt_read(struct file *filp, char __user *buf,
               size_t count, loff_t *f_pos)
{
    return -EPERM;
}

static ssize_t zcrypt_write(struct file *filp, const char __user *buf,
                size_t count, loff_t *f_pos)
{
    return -EPERM;
}

static int zcrypt_open(struct inode *inode, struct file *filp)
{
    atomic_inc(&zcrypt_open_count);
    return nonseekable_open(inode, filp);
}

static int zcrypt_release(struct inode *inode, struct file *filp)
{
    atomic_dec(&zcrypt_open_count);
    return 0;
}

/*
 * zcrypt ioctls.
 */
static long zcrypt_rsa_modexpo(struct ica_rsa_modexpo *mex)
{
    struct zcrypt_device *zdev;
    int rc;

    if (mex->outputdatalength < mex->inputdatalength)
        return -EINVAL;
    /*
     * 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;

    spin_lock_bh(&zcrypt_device_lock);
    list_for_each_entry(zdev, &zcrypt_device_list, list) {
        if (!zdev->online ||
            !zdev->ops->rsa_modexpo ||
            zdev->min_mod_size > mex->inputdatalength ||
            zdev->max_mod_size < mex->inputdatalength)
            continue;
        zcrypt_device_get(zdev);
        get_device(&zdev->ap_dev->device);
        zdev->request_count++;
        __zcrypt_decrease_preference(zdev);
        if (try_module_get(zdev->ap_dev->drv->driver.owner)) {
            spin_unlock_bh(&zcrypt_device_lock);
            rc = zdev->ops->rsa_modexpo(zdev, mex);
            spin_lock_bh(&zcrypt_device_lock);
            module_put(zdev->ap_dev->drv->driver.owner);
        }
        else
            rc = -EAGAIN;
        zdev->request_count--;
        __zcrypt_increase_preference(zdev);
        put_device(&zdev->ap_dev->device);
        zcrypt_device_put(zdev);
        spin_unlock_bh(&zcrypt_device_lock);
        return rc;
    }
    spin_unlock_bh(&zcrypt_device_lock);
    return -ENODEV;
}

static long zcrypt_rsa_crt(struct ica_rsa_modexpo_crt *crt)
{
    struct zcrypt_device *zdev;
    unsigned long long z1, z2, z3;
    int rc, copied;

    if (crt->outputdatalength < crt->inputdatalength ||
        (crt->inputdatalength & 1))
        return -EINVAL;
    /*
     * 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;

    copied = 0;
 restart:
    spin_lock_bh(&zcrypt_device_lock);
    list_for_each_entry(zdev, &zcrypt_device_list, list) {
        if (!zdev->online ||
            !zdev->ops->rsa_modexpo_crt ||
            zdev->min_mod_size > crt->inputdatalength ||
            zdev->max_mod_size < crt->inputdatalength)
            continue;
        if (zdev->short_crt && crt->inputdatalength > 240) {
            /*
             * Check inputdata for leading zeros for cards
             * that can't handle np_prime, bp_key, or
             * u_mult_inv > 128 bytes.
             */
            if (copied == 0) {
                unsigned int len;
                spin_unlock_bh(&zcrypt_device_lock);
                /* len is max 256 / 2 - 120 = 8
                 * For bigger device just assume len of leading
                 * 0s is 8 as stated in the requirements for
                 * ica_rsa_modexpo_crt struct in zcrypt.h.
                 */
                if (crt->inputdatalength <= 256)
                    len = crt->inputdatalength / 2 - 120;
                else
                    len = 8;
                if (len > sizeof(z1))
                    return -EFAULT;
                z1 = z2 = z3 = 0;
                if (copy_from_user(&z1, crt->np_prime, len) ||
                    copy_from_user(&z2, crt->bp_key, len) ||
                    copy_from_user(&z3, crt->u_mult_inv, len))
                    return -EFAULT;
                z1 = z2 = z3 = 0;
                copied = 1;
                /*
                 * We have to restart device lookup -
                 * the device list may have changed by now.
                 */
                goto restart;
            }
            if (z1 != 0ULL || z2 != 0ULL || z3 != 0ULL)
                /* The device can't handle this request. */
                continue;
        }
        zcrypt_device_get(zdev);
        get_device(&zdev->ap_dev->device);
        zdev->request_count++;
        __zcrypt_decrease_preference(zdev);
        if (try_module_get(zdev->ap_dev->drv->driver.owner)) {
            spin_unlock_bh(&zcrypt_device_lock);
            rc = zdev->ops->rsa_modexpo_crt(zdev, crt);
            spin_lock_bh(&zcrypt_device_lock);
            module_put(zdev->ap_dev->drv->driver.owner);
        }
        else
            rc = -EAGAIN;
        zdev->request_count--;
        __zcrypt_increase_preference(zdev);
        put_device(&zdev->ap_dev->device);
        zcrypt_device_put(zdev);
        spin_unlock_bh(&zcrypt_device_lock);
        return rc;
    }
    spin_unlock_bh(&zcrypt_device_lock);
    return -ENODEV;
}

static long zcrypt_send_cprb(struct ica_xcRB *xcRB)
{
    struct zcrypt_device *zdev;
    int rc;

    spin_lock_bh(&zcrypt_device_lock);
    list_for_each_entry(zdev, &zcrypt_device_list, list) {
        if (!zdev->online || !zdev->ops->send_cprb ||
            (xcRB->user_defined != AUTOSELECT &&
            AP_QID_DEVICE(zdev->ap_dev->qid) != xcRB->user_defined)
            )
            continue;
        zcrypt_device_get(zdev);
        get_device(&zdev->ap_dev->device);
        zdev->request_count++;
        __zcrypt_decrease_preference(zdev);
        if (try_module_get(zdev->ap_dev->drv->driver.owner)) {
            spin_unlock_bh(&zcrypt_device_lock);
            rc = zdev->ops->send_cprb(zdev, xcRB);
            spin_lock_bh(&zcrypt_device_lock);
            module_put(zdev->ap_dev->drv->driver.owner);
        }
        else
            rc = -EAGAIN;
        zdev->request_count--;
        __zcrypt_increase_preference(zdev);
        put_device(&zdev->ap_dev->device);
        zcrypt_device_put(zdev);
        spin_unlock_bh(&zcrypt_device_lock);
        return rc;
    }
    spin_unlock_bh(&zcrypt_device_lock);
    return -ENODEV;
}

static long zcrypt_rng(char *buffer)
{
    struct zcrypt_device *zdev;
    int rc;

    spin_lock_bh(&zcrypt_device_lock);
    list_for_each_entry(zdev, &zcrypt_device_list, list) {
        if (!zdev->online || !zdev->ops->rng)
            continue;
        zcrypt_device_get(zdev);
        get_device(&zdev->ap_dev->device);
        zdev->request_count++;
        __zcrypt_decrease_preference(zdev);
        if (try_module_get(zdev->ap_dev->drv->driver.owner)) {
            spin_unlock_bh(&zcrypt_device_lock);
            rc = zdev->ops->rng(zdev, buffer);
            spin_lock_bh(&zcrypt_device_lock);
            module_put(zdev->ap_dev->drv->driver.owner);
        } else
            rc = -EAGAIN;
        zdev->request_count--;
        __zcrypt_increase_preference(zdev);
        put_device(&zdev->ap_dev->device);
        zcrypt_device_put(zdev);
        spin_unlock_bh(&zcrypt_device_lock);
        return rc;
    }
    spin_unlock_bh(&zcrypt_device_lock);
    return -ENODEV;
}

static void zcrypt_status_mask(char status[AP_DEVICES])
{
    struct zcrypt_device *zdev;

    memset(status, 0, sizeof(char) * AP_DEVICES);
    spin_lock_bh(&zcrypt_device_lock);
    list_for_each_entry(zdev, &zcrypt_device_list, list)
        status[AP_QID_DEVICE(zdev->ap_dev->qid)] =
            zdev->online ? zdev->user_space_type : 0x0d;
    spin_unlock_bh(&zcrypt_device_lock);
}

static void zcrypt_qdepth_mask(char qdepth[AP_DEVICES])
{
    struct zcrypt_device *zdev;

    memset(qdepth, 0, sizeof(char)  * AP_DEVICES);
    spin_lock_bh(&zcrypt_device_lock);
    list_for_each_entry(zdev, &zcrypt_device_list, list) {
        spin_lock(&zdev->ap_dev->lock);
        qdepth[AP_QID_DEVICE(zdev->ap_dev->qid)] =
            zdev->ap_dev->pendingq_count +
            zdev->ap_dev->requestq_count;
        spin_unlock(&zdev->ap_dev->lock);
    }
    spin_unlock_bh(&zcrypt_device_lock);
}

static void zcrypt_perdev_reqcnt(int reqcnt[AP_DEVICES])
{
    struct zcrypt_device *zdev;

    memset(reqcnt, 0, sizeof(int) * AP_DEVICES);
    spin_lock_bh(&zcrypt_device_lock);
    list_for_each_entry(zdev, &zcrypt_device_list, list) {
        spin_lock(&zdev->ap_dev->lock);
        reqcnt[AP_QID_DEVICE(zdev->ap_dev->qid)] =
            zdev->ap_dev->total_request_count;
        spin_unlock(&zdev->ap_dev->lock);
    }
    spin_unlock_bh(&zcrypt_device_lock);
}

static int zcrypt_pendingq_count(void)
{
    struct zcrypt_device *zdev;
    int pendingq_count = 0;

    spin_lock_bh(&zcrypt_device_lock);
    list_for_each_entry(zdev, &zcrypt_device_list, list) {
        spin_lock(&zdev->ap_dev->lock);
        pendingq_count += zdev->ap_dev->pendingq_count;
        spin_unlock(&zdev->ap_dev->lock);
    }
    spin_unlock_bh(&zcrypt_device_lock);
    return pendingq_count;
}

static int zcrypt_requestq_count(void)
{
    struct zcrypt_device *zdev;
    int requestq_count = 0;

    spin_lock_bh(&zcrypt_device_lock);
    list_for_each_entry(zdev, &zcrypt_device_list, list) {
        spin_lock(&zdev->ap_dev->lock);
        requestq_count += zdev->ap_dev->requestq_count;
        spin_unlock(&zdev->ap_dev->lock);
    }
    spin_unlock_bh(&zcrypt_device_lock);
    return requestq_count;
}

static int zcrypt_count_type(int type)
{
    struct zcrypt_device *zdev;
    int device_count = 0;

    spin_lock_bh(&zcrypt_device_lock);
    list_for_each_entry(zdev, &zcrypt_device_list, list)
        if (zdev->user_space_type == type)
            device_count++;
    spin_unlock_bh(&zcrypt_device_lock);
    return device_count;
}

static long zcrypt_ica_status(struct file *filp, unsigned long arg)
{
    struct ica_z90_status *pstat;
    int ret;

    pstat = kzalloc(sizeof(*pstat), GFP_KERNEL);
    if (!pstat)
        return -ENOMEM;
    pstat->totalcount = zcrypt_device_count;
    pstat->leedslitecount = zcrypt_count_type(ZCRYPT_PCICA);
    pstat->leeds2count = zcrypt_count_type(ZCRYPT_PCICC);
    pstat->requestqWaitCount = zcrypt_requestq_count();
    pstat->pendingqWaitCount = zcrypt_pendingq_count();
    pstat->totalOpenCount = atomic_read(&zcrypt_open_count);
    pstat->cryptoDomain = ap_domain_index;
    zcrypt_status_mask(pstat->status);
    zcrypt_qdepth_mask(pstat->qdepth);
    ret = 0;
    if (copy_to_user((void __user *) arg, pstat, sizeof(*pstat)))
        ret = -EFAULT;
    kfree(pstat);
    return ret;
}

static long zcrypt_unlocked_ioctl(struct file *filp, unsigned int cmd,
                  unsigned long arg)
{
    int rc;

    switch (cmd) {
    case ICARSAMODEXPO: {
        struct ica_rsa_modexpo __user *umex = (void __user *) arg;
        struct ica_rsa_modexpo mex;
        if (copy_from_user(&mex, umex, sizeof(mex)))
            return -EFAULT;
        do {
            rc = zcrypt_rsa_modexpo(&mex);
        } while (rc == -EAGAIN);
        /* on failure: retry once again after a requested rescan */
        if ((rc == -ENODEV) && (zcrypt_process_rescan()))
            do {
                rc = zcrypt_rsa_modexpo(&mex);
            } while (rc == -EAGAIN);
        if (rc)
            return rc;
        return put_user(mex.outputdatalength, &umex->outputdatalength);
    }
    case ICARSACRT: {
        struct ica_rsa_modexpo_crt __user *ucrt = (void __user *) arg;
        struct ica_rsa_modexpo_crt crt;
        if (copy_from_user(&crt, ucrt, sizeof(crt)))
            return -EFAULT;
        do {
            rc = zcrypt_rsa_crt(&crt);
        } while (rc == -EAGAIN);
        /* on failure: retry once again after a requested rescan */
        if ((rc == -ENODEV) && (zcrypt_process_rescan()))
            do {
                rc = zcrypt_rsa_crt(&crt);
            } while (rc == -EAGAIN);
        if (rc)
            return rc;
        return put_user(crt.outputdatalength, &ucrt->outputdatalength);
    }
    case ZSECSENDCPRB: {
        struct ica_xcRB __user *uxcRB = (void __user *) arg;
        struct ica_xcRB xcRB;
        if (copy_from_user(&xcRB, uxcRB, sizeof(xcRB)))
            return -EFAULT;
        do {
            rc = zcrypt_send_cprb(&xcRB);
        } while (rc == -EAGAIN);
        /* on failure: retry once again after a requested rescan */
        if ((rc == -ENODEV) && (zcrypt_process_rescan()))
            do {
                rc = zcrypt_send_cprb(&xcRB);
            } while (rc == -EAGAIN);
        if (copy_to_user(uxcRB, &xcRB, sizeof(xcRB)))
            return -EFAULT;
        return rc;
    }
    case Z90STAT_STATUS_MASK: {
        char status[AP_DEVICES];
        zcrypt_status_mask(status);
        if (copy_to_user((char __user *) arg, status,
                 sizeof(char) * AP_DEVICES))
            return -EFAULT;
        return 0;
    }
    case Z90STAT_QDEPTH_MASK: {
        char qdepth[AP_DEVICES];
        zcrypt_qdepth_mask(qdepth);
        if (copy_to_user((char __user *) arg, qdepth,
                 sizeof(char) * AP_DEVICES))
            return -EFAULT;
        return 0;
    }
    case Z90STAT_PERDEV_REQCNT: {
        int reqcnt[AP_DEVICES];
        zcrypt_perdev_reqcnt(reqcnt);
        if (copy_to_user((int __user *) arg, reqcnt,
                 sizeof(int) * AP_DEVICES))
            return -EFAULT;
        return 0;
    }
    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. Don't add another device count ioctl,
     * you can count them yourself in the user space with the
     * output of the Z90STAT_STATUS_MASK ioctl.
     */
    case ICAZ90STATUS:
        return zcrypt_ica_status(filp, arg);
    case Z90STAT_TOTALCOUNT:
        return put_user(zcrypt_device_count, (int __user *) arg);
    case Z90STAT_PCICACOUNT:
        return put_user(zcrypt_count_type(ZCRYPT_PCICA),
                (int __user *) arg);
    case Z90STAT_PCICCCOUNT:
        return put_user(zcrypt_count_type(ZCRYPT_PCICC),
                (int __user *) arg);
    case Z90STAT_PCIXCCMCL2COUNT:
        return put_user(zcrypt_count_type(ZCRYPT_PCIXCC_MCL2),
                (int __user *) arg);
    case Z90STAT_PCIXCCMCL3COUNT:
        return put_user(zcrypt_count_type(ZCRYPT_PCIXCC_MCL3),
                (int __user *) arg);
    case Z90STAT_PCIXCCCOUNT:
        return put_user(zcrypt_count_type(ZCRYPT_PCIXCC_MCL2) +
                zcrypt_count_type(ZCRYPT_PCIXCC_MCL3),
                (int __user *) arg);
    case Z90STAT_CEX2CCOUNT:
        return put_user(zcrypt_count_type(ZCRYPT_CEX2C),
                (int __user *) arg);
    case Z90STAT_CEX2ACOUNT:
        return put_user(zcrypt_count_type(ZCRYPT_CEX2A),
                (int __user *) arg);
    default:
        /* unknown ioctl number */
        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 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;
    long rc;

    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(&mex64);
    } while (rc == -EAGAIN);
    /* on failure: retry once again after a requested rescan */
    if ((rc == -ENODEV) && (zcrypt_process_rescan()))
        do {
            rc = zcrypt_rsa_modexpo(&mex64);
        } while (rc == -EAGAIN);
    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 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;
    long rc;

    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(&crt64);
    } while (rc == -EAGAIN);
    /* on failure: retry once again after a requested rescan */
    if ((rc == -ENODEV) && (zcrypt_process_rescan()))
        do {
            rc = zcrypt_rsa_crt(&crt64);
        } while (rc == -EAGAIN);
    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;
} __attribute__((packed));

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

    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(&xcRB64);
    } while (rc == -EAGAIN);
    /* on failure: retry once again after a requested rescan */
    if ((rc == -ENODEV) && (zcrypt_process_rescan()))
        do {
            rc = zcrypt_send_cprb(&xcRB64);
        } while (rc == -EAGAIN);
    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)
{
    if (cmd == ICARSAMODEXPO)
        return trans_modexpo32(filp, cmd, arg);
    if (cmd == ICARSACRT)
        return trans_modexpo_crt32(filp, cmd, arg);
    if (cmd == ZSECSENDCPRB)
        return trans_xcRB32(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,
};

/*
 * Deprecated /proc entry support.
 */
static struct proc_dir_entry *zcrypt_entry;

static void sprintcl(struct seq_file *m, unsigned char *addr, unsigned int len)
{
    int i;

    for (i = 0; i < len; i++)
        seq_printf(m, "%01x", (unsigned int) addr[i]);
    seq_putc(m, ' ');
}

static void sprintrw(struct seq_file *m, unsigned char *addr, unsigned int len)
{
    int inl, c, cx;

    seq_printf(m, "    ");
    inl = 0;
    for (c = 0; c < (len / 16); c++) {
        sprintcl(m, addr+inl, 16);
        inl += 16;
    }
    cx = len%16;
    if (cx) {
        sprintcl(m, addr+inl, cx);
        inl += cx;
    }
    seq_putc(m, '\n');
}

static void sprinthx(unsigned char *title, struct seq_file *m,
             unsigned char *addr, unsigned int len)
{
    int inl, r, rx;

    seq_printf(m, "\n%s\n", title);
    inl = 0;
    for (r = 0; r < (len / 64); r++) {
        sprintrw(m, addr+inl, 64);
        inl += 64;
    }
    rx = len % 64;
    if (rx) {
        sprintrw(m, addr+inl, rx);
        inl += rx;
    }
    seq_putc(m, '\n');
}

static void sprinthx4(unsigned char *title, struct seq_file *m,
              unsigned int *array, unsigned int len)
{
    int r;

    seq_printf(m, "\n%s\n", title);
    for (r = 0; r < len; r++) {
        if ((r % 8) == 0)
            seq_printf(m, "    ");
        seq_printf(m, "%08X ", array[r]);
        if ((r % 8) == 7)
            seq_putc(m, '\n');
    }
    seq_putc(m, '\n');
}

static int zcrypt_proc_show(struct seq_file *m, void *v)
{
    char workarea[sizeof(int) * AP_DEVICES];

    seq_printf(m, "\nzcrypt version: %d.%d.%d\n",
           ZCRYPT_VERSION, ZCRYPT_RELEASE, ZCRYPT_VARIANT);
    seq_printf(m, "Cryptographic domain: %d\n", ap_domain_index);
    seq_printf(m, "Total device count: %d\n", zcrypt_device_count);
    seq_printf(m, "PCICA count: %d\n", zcrypt_count_type(ZCRYPT_PCICA));
    seq_printf(m, "PCICC count: %d\n", zcrypt_count_type(ZCRYPT_PCICC));
    seq_printf(m, "PCIXCC MCL2 count: %d\n",
           zcrypt_count_type(ZCRYPT_PCIXCC_MCL2));
    seq_printf(m, "PCIXCC MCL3 count: %d\n",
           zcrypt_count_type(ZCRYPT_PCIXCC_MCL3));
    seq_printf(m, "CEX2C count: %d\n", zcrypt_count_type(ZCRYPT_CEX2C));
    seq_printf(m, "CEX2A count: %d\n", zcrypt_count_type(ZCRYPT_CEX2A));
    seq_printf(m, "CEX3C count: %d\n", zcrypt_count_type(ZCRYPT_CEX3C));
    seq_printf(m, "CEX3A count: %d\n", zcrypt_count_type(ZCRYPT_CEX3A));
    seq_printf(m, "requestq count: %d\n", zcrypt_requestq_count());
    seq_printf(m, "pendingq count: %d\n", zcrypt_pendingq_count());
    seq_printf(m, "Total open handles: %d\n\n",
           atomic_read(&zcrypt_open_count));
    zcrypt_status_mask(workarea);
    sprinthx("Online devices: 1=PCICA 2=PCICC 3=PCIXCC(MCL2) "
         "4=PCIXCC(MCL3) 5=CEX2C 6=CEX2A 7=CEX3C 8=CEX3A",
         m, workarea, AP_DEVICES);
    zcrypt_qdepth_mask(workarea);
    sprinthx("Waiting work element counts", m, workarea, AP_DEVICES);
    zcrypt_perdev_reqcnt((int *) workarea);
    sprinthx4("Per-device successfully completed request counts",
          m, (unsigned int *) workarea, AP_DEVICES);
    return 0;
}

static int zcrypt_proc_open(struct inode *inode, struct file *file)
{
    return single_open(file, zcrypt_proc_show, NULL);
}

static void zcrypt_disable_card(int index)
{
    struct zcrypt_device *zdev;

    spin_lock_bh(&zcrypt_device_lock);
    list_for_each_entry(zdev, &zcrypt_device_list, list)
        if (AP_QID_DEVICE(zdev->ap_dev->qid) == index) {
            zdev->online = 0;
            ap_flush_queue(zdev->ap_dev);
            break;
        }
    spin_unlock_bh(&zcrypt_device_lock);
}

static void zcrypt_enable_card(int index)
{
    struct zcrypt_device *zdev;

    spin_lock_bh(&zcrypt_device_lock);
    list_for_each_entry(zdev, &zcrypt_device_list, list)
        if (AP_QID_DEVICE(zdev->ap_dev->qid) == index) {
            zdev->online = 1;
            break;
        }
    spin_unlock_bh(&zcrypt_device_lock);
}

static ssize_t zcrypt_proc_write(struct file *file, const char __user *buffer,
                 size_t count, loff_t *pos)
{
    unsigned char *lbuf, *ptr;
    size_t local_count;
    int j;

    if (count <= 0)
        return 0;

#define LBUFSIZE 1200UL
    lbuf = kmalloc(LBUFSIZE, GFP_KERNEL);
    if (!lbuf)
        return 0;

    local_count = min(LBUFSIZE - 1, count);
    if (copy_from_user(lbuf, buffer, local_count) != 0) {
        kfree(lbuf);
        return -EFAULT;
    }
    lbuf[local_count] = '\0';

    ptr = strstr(lbuf, "Online devices");
    if (!ptr)
        goto out;
    ptr = strstr(ptr, "\n");
    if (!ptr)
        goto out;
    ptr++;

    if (strstr(ptr, "Waiting work element counts") == NULL)
        goto out;

    for (j = 0; j < 64 && *ptr; ptr++) {
        /*
         * '0' for no device, '1' for PCICA, '2' for PCICC,
         * '3' for PCIXCC_MCL2, '4' for PCIXCC_MCL3,
         * '5' for CEX2C and '6' for CEX2A'
         * '7' for CEX3C and '8' for CEX3A
         */
        if (*ptr >= '0' && *ptr <= '8')
            j++;
        else if (*ptr == 'd' || *ptr == 'D')
            zcrypt_disable_card(j++);
        else if (*ptr == 'e' || *ptr == 'E')
            zcrypt_enable_card(j++);
        else if (*ptr != ' ' && *ptr != '\t')
            break;
    }
out:
    kfree(lbuf);
    return count;
}

static const struct file_operations zcrypt_proc_fops = {
    .owner      = THIS_MODULE,
    .open       = zcrypt_proc_open,
    .read       = seq_read,
    .llseek     = seq_lseek,
    .release    = single_release,
    .write      = zcrypt_proc_write,
};

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,
};

static 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;
        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;
}

static 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);
}

int __init zcrypt_debug_init(void)
{
    debugfs_root = debugfs_create_dir("zcrypt", NULL);

    zcrypt_dbf_common = debug_register("zcrypt_common", 1, 1, 16);
    debug_register_view(zcrypt_dbf_common, &debug_hex_ascii_view);
    debug_set_level(zcrypt_dbf_common, DBF_ERR);

    zcrypt_dbf_devices = debug_register("zcrypt_devices", 1, 1, 16);
    debug_register_view(zcrypt_dbf_devices, &debug_hex_ascii_view);
    debug_set_level(zcrypt_dbf_devices, DBF_ERR);

    return 0;
}

void zcrypt_debug_exit(void)
{
    debugfs_remove(debugfs_root);
    if (zcrypt_dbf_common)
        debug_unregister(zcrypt_dbf_common);
    if (zcrypt_dbf_devices)
        debug_unregister(zcrypt_dbf_devices);
}

int __init zcrypt_api_init(void)
{
    int rc;

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

    atomic_set(&zcrypt_rescan_req, 0);

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

    /* Set up the proc file system */
    zcrypt_entry = proc_create("driver/z90crypt", 0644, NULL, &zcrypt_proc_fops);
    if (!zcrypt_entry) {
        rc = -ENOMEM;
        goto out_misc;
    }

    return 0;

out_misc:
    misc_deregister(&zcrypt_misc_device);
out:
    return rc;
}

void zcrypt_api_exit(void)
{
    remove_proc_entry("driver/z90crypt", NULL);
    misc_deregister(&zcrypt_misc_device);
    zcrypt_debug_exit();
}

module_init(zcrypt_api_init);
module_exit(zcrypt_api_exit);