s390/zcrypt: add multi domain support

Currently the ap infrastructure only supports one domain at a time.
This feature extends the generic cryptographic device driver to
support multiple cryptographic domains simultaneously.

There are now card and queue devices on the AP bus with independent
card and queue drivers. The new /sys layout is as follows:

/sys/bus/ap
    devices
        <xx>.<yyyy> -> ../../../devices/ap/card<xx>/<xx>.<yyyy>
        ...
        card<xx> -> ../../../devices/ap/card<xx>
        ...
    drivers
        <drv>card
            card<xx> -> ../../../../devices/ap/card<xx>
        <drv>queue
            <xx>.<yyyy> -> ../../../../devices/ap/card<xx>/<xx>.<yyyy>
            ...

/sys/devices/ap
    card<xx>
        <xx>.<yyyy>
            driver -> ../../../../bus/ap/drivers/<zzz>queue
            ...
        driver -> ../../../bus/ap/drivers/<drv>card
        ...

The two digit <xx> field is the card number, the four digit <yyyy>
field is the queue number and <drv> is the name of the device driver,
e.g. "cex4".

For compatability /sys/bus/ap/card<xx> for the old layout has to exist,
including the attributes that used to reside there.

With additional contributions from Harald Freudenberger and
Martin Schwidefsky.

Signed-off-by: Ingo Tuchscherer <ingo.tuchscherer@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 181 insertions, 0 deletions

diff --git a/drivers/s390/crypto/zcrypt_card.c b/drivers/s390/crypto/zcrypt_card.c
new file mode 100644
index 000000000000..57873d775e95
--- /dev/null
+++ b/drivers/s390/crypto/zcrypt_card.c
@@ -0,0 +1,181 @@
+/*
+ *  zcrypt 2.1.0
+ *
+ *  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>
+ *
+ * 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.
+ */
+
+#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 card devices.
+ */
+
+static ssize_t zcrypt_card_type_show(struct device *dev,
+				     struct device_attribute *attr, char *buf)
+{
+	struct zcrypt_card *zc = to_ap_card(dev)->private;
+
+	return snprintf(buf, PAGE_SIZE, "%s\n", zc->type_string);
+}
+
+static DEVICE_ATTR(type, 0444, zcrypt_card_type_show, NULL);
+
+static ssize_t zcrypt_card_online_show(struct device *dev,
+				       struct device_attribute *attr,
+				       char *buf)
+{
+	struct zcrypt_card *zc = to_ap_card(dev)->private;
+
+	return snprintf(buf, PAGE_SIZE, "%d\n", zc->online);
+}
+
+static ssize_t zcrypt_card_online_store(struct device *dev,
+					struct device_attribute *attr,
+					const char *buf, size_t count)
+{
+	struct zcrypt_card *zc = to_ap_card(dev)->private;
+	struct zcrypt_queue *zq;
+	int online, id;
+
+	if (sscanf(buf, "%d\n", &online) != 1 || online < 0 || online > 1)
+		return -EINVAL;
+
+	zc->online = online;
+	id = zc->card->id;
+	ZCRYPT_DBF_DEV(DBF_INFO, zc, "card%02xo%dman", id, online);
+	spin_lock(&zcrypt_list_lock);
+	list_for_each_entry(zq, &zc->zqueues, list)
+		zcrypt_queue_force_online(zq, online);
+	spin_unlock(&zcrypt_list_lock);
+	return count;
+}
+
+static DEVICE_ATTR(online, 0644, zcrypt_card_online_show,
+		   zcrypt_card_online_store);
+
+static struct attribute *zcrypt_card_attrs[] = {
+	&dev_attr_type.attr,
+	&dev_attr_online.attr,
+	NULL,
+};
+
+static struct attribute_group zcrypt_card_attr_group = {
+	.attrs = zcrypt_card_attrs,
+};
+
+struct zcrypt_card *zcrypt_card_alloc(void)
+{
+	struct zcrypt_card *zc;
+
+	zc = kzalloc(sizeof(struct zcrypt_card), GFP_KERNEL);
+	if (!zc)
+		return NULL;
+	INIT_LIST_HEAD(&zc->list);
+	INIT_LIST_HEAD(&zc->zqueues);
+	zc->dbf_area = zcrypt_dbf_cards;
+	kref_init(&zc->refcount);
+	return zc;
+}
+EXPORT_SYMBOL(zcrypt_card_alloc);
+
+void zcrypt_card_free(struct zcrypt_card *zc)
+{
+	kfree(zc);
+}
+EXPORT_SYMBOL(zcrypt_card_free);
+
+static void zcrypt_card_release(struct kref *kref)
+{
+	struct zcrypt_card *zdev =
+		container_of(kref, struct zcrypt_card, refcount);
+	zcrypt_card_free(zdev);
+}
+
+void zcrypt_card_get(struct zcrypt_card *zc)
+{
+	kref_get(&zc->refcount);
+}
+EXPORT_SYMBOL(zcrypt_card_get);
+
+int zcrypt_card_put(struct zcrypt_card *zc)
+{
+	return kref_put(&zc->refcount, zcrypt_card_release);
+}
+EXPORT_SYMBOL(zcrypt_card_put);
+
+/**
+ * zcrypt_card_register() - Register a crypto card device.
+ * @zc: Pointer to a crypto card device
+ *
+ * Register a crypto card device. Returns 0 if successful.
+ */
+int zcrypt_card_register(struct zcrypt_card *zc)
+{
+	int rc;
+
+	rc = sysfs_create_group(&zc->card->ap_dev.device.kobj,
+				&zcrypt_card_attr_group);
+	if (rc)
+		return rc;
+
+	spin_lock(&zcrypt_list_lock);
+	list_add_tail(&zc->list, &zcrypt_card_list);
+	spin_unlock(&zcrypt_list_lock);
+
+	zc->online = 1;
+	return rc;
+}
+EXPORT_SYMBOL(zcrypt_card_register);
+
+/**
+ * zcrypt_card_unregister(): Unregister a crypto card device.
+ * @zc: Pointer to crypto card device
+ *
+ * Unregister a crypto card device.
+ */
+void zcrypt_card_unregister(struct zcrypt_card *zc)
+{
+	spin_lock(&zcrypt_list_lock);
+	list_del_init(&zc->list);
+	spin_unlock(&zcrypt_list_lock);
+	sysfs_remove_group(&zc->card->ap_dev.device.kobj,
+			   &zcrypt_card_attr_group);
+}
+EXPORT_SYMBOL(zcrypt_card_unregister);