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, 221 insertions, 0 deletions

diff --git a/drivers/s390/crypto/zcrypt_queue.c b/drivers/s390/crypto/zcrypt_queue.c
new file mode 100644
index 000000000000..c70b2528d9a3
--- /dev/null
+++ b/drivers/s390/crypto/zcrypt_queue.c
@@ -0,0 +1,221 @@
+/*
+ *  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 queue devices.
+ */
+
+static ssize_t zcrypt_queue_online_show(struct device *dev,
+					struct device_attribute *attr,
+					char *buf)
+{
+	struct zcrypt_queue *zq = to_ap_queue(dev)->private;
+
+	return snprintf(buf, PAGE_SIZE, "%d\n", zq->online);
+}
+
+static ssize_t zcrypt_queue_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_DEV(DBF_INFO, zq, "dev%02x%04xo%dman",
+		       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(online, 0644, zcrypt_queue_online_show,
+		   zcrypt_queue_online_store);
+
+static struct attribute *zcrypt_queue_attrs[] = {
+	&dev_attr_online.attr,
+	NULL,
+};
+
+static 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);
+	zq->dbf_area = zcrypt_dbf_devices;
+	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_DEV(DBF_INFO, zq, "dev%02x%04xo%dreg",
+		       AP_QID_CARD(zq->queue->qid),
+		       AP_QID_QUEUE(zq->queue->qid),
+		       zq->online);
+	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;
+
+	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);