s390/zcrypt: Separate msgtype implementation from card modules.

Msgtype implementations are now separated from card specific modules
and can be dynamically registered. Existing msgtype implementations
are restructured in modules.

Signed-off-by: Holger Dengler <hd@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 70 insertions, 3 deletions

diff --git a/drivers/s390/crypto/zcrypt_api.c b/drivers/s390/crypto/zcrypt_api.c
index 2f94132246a1..f1f026e0b189 100644
--- a/drivers/s390/crypto/zcrypt_api.c
+++ b/drivers/s390/crypto/zcrypt_api.c
@@ -1,7 +1,7 @@
 /*
  *  zcrypt 2.1.0
  *
- *  Copyright IBM Corp. 2001, 2006
+ *  Copyright IBM Corp. 2001, 2012
  *  Author(s): Robert Burroughs
  *             Eric Rossman (edrossma@us.ibm.com)
  *             Cornelia Huck <cornelia.huck@de.ibm.com>
@@ -9,6 +9,7 @@
  *  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>
  *
  * 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
@@ -44,8 +45,8 @@
  * Module description.
  */
 MODULE_AUTHOR("IBM Corporation");
-MODULE_DESCRIPTION("Cryptographic Coprocessor interface, "
-                   "Copyright IBM Corp. 2001, 2006");
+MODULE_DESCRIPTION("Cryptographic Coprocessor interface, " \
+                   "Copyright IBM Corp. 2001, 2012");
 MODULE_LICENSE("GPL");
 
 static DEFINE_SPINLOCK(zcrypt_device_lock);
@@ -56,6 +57,9 @@ static atomic_t zcrypt_open_count = ATOMIC_INIT(0);
 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);
+
 /*
  * Device attributes common for all crypto devices.
  */
@@ -215,6 +219,8 @@ 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)
@@ -269,6 +275,67 @@ void zcrypt_device_unregister(struct zcrypt_device *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);
+
 /**
  * zcrypt_read (): Not supported beyond zcrypt 1.3.1.
  *