text: // SPDX-License-Identifier: GPL-2.0+
  /*
   *  Copyright IBM Corp. 2001, 2012
   *  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>
   */
  
  #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 <linux/uaccess.h>
  #include <linux/hw_random.h>
  #include <linux/debugfs.h>
  #include <asm/debug.h>
  
  #include "zcrypt_debug.h"
  #include "zcrypt_api.h"
  
  #include "zcrypt_msgtype6.h"
  #include "zcrypt_msgtype50.h"
  
  /*
   * Device attributes common for all crypto queue devices.
   */
  
  static ssize_t online_show(struct device *dev,
  			   struct device_attribute *attr,
  			   char *buf)
  {
  	struct zcrypt_queue *zq = to_ap_queue(dev)->private;
  
  	return scnprintf(buf, PAGE_SIZE, "%d\n", zq->online);
  }
  
  static ssize_t online_store(struct device *dev,
  			    struct device_attribute *attr,
  			    const char *buf, size_t count)
  {
  	struct zcrypt_queue *zq = to_ap_queue(dev)->private;
  	struct zcrypt_card *zc = zq->zcard;
  	int online;
  
  	if (sscanf(buf, "%d\n", &online) != 1 || online < 0 || online > 1)
  		return -EINVAL;
  
  	if (online && !zc->online)
  		return -EINVAL;
  	zq->online = online;
  
  	ZCRYPT_DBF(DBF_INFO, "queue=%02x.%04x online=%d\n",
  		   AP_QID_CARD(zq->queue->qid),
  		   AP_QID_QUEUE(zq->queue->qid),
  		   online);
  
  	if (!online)
  		ap_flush_queue(zq->queue);
  	return count;
  }
  
  static DEVICE_ATTR_RW(online);
  
  static ssize_t load_show(struct device *dev,
  			 struct device_attribute *attr,
  			 char *buf)
  {
  	struct zcrypt_queue *zq = to_ap_queue(dev)->private;
  
  	return scnprintf(buf, PAGE_SIZE, "%d\n", atomic_read(&zq->load));
  }
  
  static DEVICE_ATTR_RO(load);
  
  static struct attribute *zcrypt_queue_attrs[] = {
  	&dev_attr_online.attr,
  	&dev_attr_load.attr,
  	NULL,
  };
  
  static const struct attribute_group zcrypt_queue_attr_group = {
  	.attrs = zcrypt_queue_attrs,
  };
  
  void zcrypt_queue_force_online(struct zcrypt_queue *zq, int online)
  {
  	zq->online = online;
  	if (!online)
  		ap_flush_queue(zq->queue);
  }
  
  struct zcrypt_queue *zcrypt_queue_alloc(size_t max_response_size)
  {
  	struct zcrypt_queue *zq;
  
  	zq = kzalloc(sizeof(struct zcrypt_queue), GFP_KERNEL);
  	if (!zq)
  		return NULL;
  	zq->reply.message = kmalloc(max_response_size, GFP_KERNEL);
  	if (!zq->reply.message)
  		goto out_free;
  	zq->reply.length = max_response_size;
  	INIT_LIST_HEAD(&zq->list);
  	kref_init(&zq->refcount);
  	return zq;
  
  out_free:
  	kfree(zq);
  	return NULL;
  }
  EXPORT_SYMBOL(zcrypt_queue_alloc);
  
  void zcrypt_queue_free(struct zcrypt_queue *zq)
  {
  	kfree(zq->reply.message);
  	kfree(zq);
  }
  EXPORT_SYMBOL(zcrypt_queue_free);
  
  static void zcrypt_queue_release(struct kref *kref)
  {
  	struct zcrypt_queue *zq =
  		container_of(kref, struct zcrypt_queue, refcount);
  	zcrypt_queue_free(zq);
  }
  
  void zcrypt_queue_get(struct zcrypt_queue *zq)
  {
  	kref_get(&zq->refcount);
  }
  EXPORT_SYMBOL(zcrypt_queue_get);
  
  int zcrypt_queue_put(struct zcrypt_queue *zq)
  {
  	return kref_put(&zq->refcount, zcrypt_queue_release);
  }
  EXPORT_SYMBOL(zcrypt_queue_put);
  
  /**
   * zcrypt_queue_register() - Register a crypto queue device.
   * @zq: Pointer to a crypto queue device
   *
   * Register a crypto queue device. Returns 0 if successful.
   */
  int zcrypt_queue_register(struct zcrypt_queue *zq)
  {
  	struct zcrypt_card *zc;
  	int rc;
  
  	spin_lock(&zcrypt_list_lock);
  	zc = zq->queue->card->private;
  	zcrypt_card_get(zc);
  	zq->zcard = zc;
  	zq->online = 1;	/* New devices are online by default. */
  
  	ZCRYPT_DBF(DBF_INFO, "queue=%02x.%04x register online=1\n",
  		   AP_QID_CARD(zq->queue->qid), AP_QID_QUEUE(zq->queue->qid));
  
  	list_add_tail(&zq->list, &zc->zqueues);
  	zcrypt_device_count++;
  	spin_unlock(&zcrypt_list_lock);
  
  	rc = sysfs_create_group(&zq->queue->ap_dev.device.kobj,
  				&zcrypt_queue_attr_group);
  	if (rc)
  		goto out;
  	get_device(&zq->queue->ap_dev.device);
  
  	if (zq->ops->rng) {
  		rc = zcrypt_rng_device_add();
  		if (rc)
  			goto out_unregister;
  	}
  	return 0;
  
  out_unregister:
  	sysfs_remove_group(&zq->queue->ap_dev.device.kobj,
  			   &zcrypt_queue_attr_group);
  	put_device(&zq->queue->ap_dev.device);
  out:
  	spin_lock(&zcrypt_list_lock);
  	list_del_init(&zq->list);
  	spin_unlock(&zcrypt_list_lock);
  	zcrypt_card_put(zc);
  	return rc;
  }
  EXPORT_SYMBOL(zcrypt_queue_register);
  
  /**
   * zcrypt_queue_unregister(): Unregister a crypto queue device.
   * @zq: Pointer to crypto queue device
   *
   * Unregister a crypto queue device.
   */
  void zcrypt_queue_unregister(struct zcrypt_queue *zq)
  {
  	struct zcrypt_card *zc;
  
  	ZCRYPT_DBF(DBF_INFO, "queue=%02x.%04x unregister\n",
  		   AP_QID_CARD(zq->queue->qid), AP_QID_QUEUE(zq->queue->qid));
  
  	zc = zq->zcard;
  	spin_lock(&zcrypt_list_lock);
  	list_del_init(&zq->list);
  	zcrypt_device_count--;
  	spin_unlock(&zcrypt_list_lock);
  	zcrypt_card_put(zc);
  	if (zq->ops->rng)
  		zcrypt_rng_device_remove();
  	sysfs_remove_group(&zq->queue->ap_dev.device.kobj,
  			   &zcrypt_queue_attr_group);
  	put_device(&zq->queue->ap_dev.device);
  	zcrypt_queue_put(zq);
  }
  EXPORT_SYMBOL(zcrypt_queue_unregister);
  