[S390] zcrypt user space interface.

The user space interface of the zcrypt device driver implements the old
user space interface as defined by the old z90crypt driver. Everything
is there, the /dev/z90crypt misc character device, all the lovely ioctls
and the /proc file. Even writing to the z90crypt proc file to configure
the crypto device still works. It stands to reason to remove the proc
write function someday since a much cleaner configuration via the sysfs
is now available.

The ap bus device drivers register crypto cards to the zcrypt user
space interface. The request router of the user space interface
picks one of the registered cards based on the predicted latency
for the request and calls the driver via a callback found in the
zcrypt_ops of the device. The request router only knows which
operations the card can do and the minimum / maximum number of bits
a request can have.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Ralph Wuerthner <rwuerthn@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

drivers/s390/crypto/zcrypt_api.h

+/*
+ *  linux/drivers/s390/crypto/zcrypt_api.h
+ *
+ *  zcrypt 2.0.0
+ *
+ *  Copyright (C)  2001, 2006 IBM Corporation
+ *  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>
+ *
+ * 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.
+ */
+
+#ifndef _ZCRYPT_API_H_
+#define _ZCRYPT_API_H_
+
+/**
+ * Macro definitions
+ *
+ * PDEBUG debugs in the form "zcrypt: function_name -> message"
+ *
+ * PRINTK is like PDEBUG, except that it is always enabled
+ * PRINTKN is like PRINTK, except that it does not include the function name
+ * PRINTKW is like PRINTK, except that it uses KERN_WARNING
+ * PRINTKC is like PRINTK, except that it uses KERN_CRIT
+ */
+#define DEV_NAME	"zcrypt"
+
+#define PRINTK(fmt, args...) \
+	printk(KERN_DEBUG DEV_NAME ": %s -> " fmt, __FUNCTION__ , ## args)
+#define PRINTKN(fmt, args...) \
+	printk(KERN_DEBUG DEV_NAME ": " fmt, ## args)
+#define PRINTKW(fmt, args...) \
+	printk(KERN_WARNING DEV_NAME ": %s -> " fmt, __FUNCTION__ , ## args)
+#define PRINTKC(fmt, args...) \
+	printk(KERN_CRIT DEV_NAME ": %s -> " fmt, __FUNCTION__ , ## args)
+
+#ifdef ZCRYPT_DEBUG
+#define PDEBUG(fmt, args...) \
+	printk(KERN_DEBUG DEV_NAME ": %s -> " fmt, __FUNCTION__ , ## args)
+#else
+#define PDEBUG(fmt, args...) do {} while (0)
+#endif
+
+#include "ap_bus.h"
+#include <asm/zcrypt.h>
+
+/* deprecated status calls */
+#define ICAZ90STATUS		_IOR(ZCRYPT_IOCTL_MAGIC, 0x10, struct ica_z90_status)
+#define Z90STAT_PCIXCCCOUNT	_IOR(ZCRYPT_IOCTL_MAGIC, 0x43, int)
+
+/**
+ * This structure is deprecated and the corresponding ioctl() has been
+ * replaced with individual ioctl()s for each piece of data!
+ */
+struct ica_z90_status {
+	int totalcount;
+	int leedslitecount; // PCICA
+	int leeds2count;    // PCICC
+	// int PCIXCCCount; is not in struct for backward compatibility
+	int requestqWaitCount;
+	int pendingqWaitCount;
+	int totalOpenCount;
+	int cryptoDomain;
+	// status: 0=not there, 1=PCICA, 2=PCICC, 3=PCIXCC_MCL2, 4=PCIXCC_MCL3,
+	//	   5=CEX2C
+	unsigned char status[64];
+	// qdepth: # work elements waiting for each device
+	unsigned char qdepth[64];
+};
+
+/**
+ * device type for an actual device is either PCICA, PCICC, PCIXCC_MCL2,
+ * PCIXCC_MCL3, CEX2C, or CEX2A
+ *
+ * NOTE: PCIXCC_MCL3 refers to a PCIXCC with May 2004 version of Licensed
+ *	 Internal Code (LIC) (EC J12220 level 29).
+ *	 PCIXCC_MCL2 refers to any LIC before this level.
+ */
+#define ZCRYPT_PCICA		1
+#define ZCRYPT_PCICC		2
+#define ZCRYPT_PCIXCC_MCL2	3
+#define ZCRYPT_PCIXCC_MCL3	4
+#define ZCRYPT_CEX2C		5
+#define ZCRYPT_CEX2A		6
+
+struct zcrypt_device;
+
+struct zcrypt_ops {
+	long (*rsa_modexpo)(struct zcrypt_device *, struct ica_rsa_modexpo *);
+	long (*rsa_modexpo_crt)(struct zcrypt_device *,
+				struct ica_rsa_modexpo_crt *);
+};
+
+struct zcrypt_device {
+	struct list_head list;		/* Device list. */
+	spinlock_t lock;		/* Per device lock. */
+	struct kref refcount;		/* device refcounting */
+	struct ap_device *ap_dev;	/* The "real" ap device. */
+	struct zcrypt_ops *ops;		/* Crypto operations. */
+	int online;			/* User online/offline */
+
+	int user_space_type;		/* User space device id. */
+	char *type_string;		/* User space device name. */
+	int min_mod_size;		/* Min number of bits. */
+	int max_mod_size;		/* Max number of bits. */
+	int short_crt;			/* Card has crt length restriction. */
+	int speed_rating;		/* Speed of the crypto device. */
+
+	int request_count;		/* # current requests. */
+
+	struct ap_message reply;	/* Per-device reply structure. */
+};
+
+struct zcrypt_device *zcrypt_device_alloc(size_t);
+void zcrypt_device_free(struct zcrypt_device *);
+void zcrypt_device_get(struct zcrypt_device *);
+int zcrypt_device_put(struct zcrypt_device *);
+int zcrypt_device_register(struct zcrypt_device *);
+void zcrypt_device_unregister(struct zcrypt_device *);
+int zcrypt_api_init(void);
+void zcrypt_api_exit(void);
+
+#endif /* _ZCRYPT_API_H_ */

include/asm-s390/zcrypt.h

+/*
+ *  include/asm-s390/zcrypt.h
+ *
+ *  zcrypt 2.0.0 (user-visible header)
+ *
+ *  Copyright (C)  2001, 2006 IBM Corporation
+ *  Author(s): Robert Burroughs
+ *	       Eric Rossman (edrossma@us.ibm.com)
+ *
+ *  Hotplug & misc device support: Jochen Roehrig (roehrig@de.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.
+ *
+ * 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.
+ */
+
+#ifndef __ASM_S390_ZCRYPT_H
+#define __ASM_S390_ZCRYPT_H
+
+#define ZCRYPT_VERSION 2
+#define ZCRYPT_RELEASE 1
+#define ZCRYPT_VARIANT 0
+
+#include <linux/ioctl.h>
+#include <linux/compiler.h>
+
+/**
+ * struct ica_rsa_modexpo
+ *
+ * Requirements:
+ * - outputdatalength is at least as large as inputdatalength.
+ * - All key parts are right justified in their fields, padded on
+ *   the left with zeroes.
+ * - length(b_key) = inputdatalength
+ * - length(n_modulus) = inputdatalength
+ */
+struct ica_rsa_modexpo {
+	char __user *	inputdata;
+	unsigned int	inputdatalength;
+	char __user *	outputdata;
+	unsigned int	outputdatalength;
+	char __user *	b_key;
+	char __user *	n_modulus;
+};
+
+/**
+ * struct ica_rsa_modexpo_crt
+ *
+ * Requirements:
+ * - inputdatalength is even.
+ * - outputdatalength is at least as large as inputdatalength.
+ * - All key parts are right justified in their fields, padded on
+ *   the left with zeroes.
+ * - length(bp_key)	= inputdatalength/2 + 8
+ * - length(bq_key)	= inputdatalength/2
+ * - length(np_key)	= inputdatalength/2 + 8
+ * - length(nq_key)	= inputdatalength/2
+ * - length(u_mult_inv) = inputdatalength/2 + 8
+ */
+struct ica_rsa_modexpo_crt {
+	char __user *	inputdata;
+	unsigned int	inputdatalength;
+	char __user *	outputdata;
+	unsigned int	outputdatalength;
+	char __user *	bp_key;
+	char __user *	bq_key;
+	char __user *	np_prime;
+	char __user *	nq_prime;
+	char __user *	u_mult_inv;
+};
+
+#define ZCRYPT_IOCTL_MAGIC 'z'
+
+/**
+ * Interface notes:
+ *
+ * The ioctl()s which are implemented (along with relevant details)
+ * are:
+ *
+ *   ICARSAMODEXPO
+ *     Perform an RSA operation using a Modulus-Exponent pair
+ *     This takes an ica_rsa_modexpo struct as its arg.
+ *
+ *     NOTE: please refer to the comments preceding this structure
+ *	     for the implementation details for the contents of the
+ *	     block
+ *
+ *   ICARSACRT
+ *     Perform an RSA operation using a Chinese-Remainder Theorem key
+ *     This takes an ica_rsa_modexpo_crt struct as its arg.
+ *
+ *     NOTE: please refer to the comments preceding this structure
+ *	     for the implementation details for the contents of the
+ *	     block
+ *
+ *   Z90STAT_TOTALCOUNT
+ *     Return an integer count of all device types together.
+ *
+ *   Z90STAT_PCICACOUNT
+ *     Return an integer count of all PCICAs.
+ *
+ *   Z90STAT_PCICCCOUNT
+ *     Return an integer count of all PCICCs.
+ *
+ *   Z90STAT_PCIXCCMCL2COUNT
+ *     Return an integer count of all MCL2 PCIXCCs.
+ *
+ *   Z90STAT_PCIXCCMCL3COUNT
+ *     Return an integer count of all MCL3 PCIXCCs.
+ *
+ *   Z90STAT_CEX2CCOUNT
+ *     Return an integer count of all CEX2Cs.
+ *
+ *   Z90STAT_CEX2ACOUNT
+ *     Return an integer count of all CEX2As.
+ *
+ *   Z90STAT_REQUESTQ_COUNT
+ *     Return an integer count of the number of entries waiting to be
+ *     sent to a device.
+ *
+ *   Z90STAT_PENDINGQ_COUNT
+ *     Return an integer count of the number of entries sent to a
+ *     device awaiting the reply.
+ *
+ *   Z90STAT_TOTALOPEN_COUNT
+ *     Return an integer count of the number of open file handles.
+ *
+ *   Z90STAT_DOMAIN_INDEX
+ *     Return the integer value of the Cryptographic Domain.
+ *
+ *   Z90STAT_STATUS_MASK
+ *     Return an 64 element array of unsigned chars for the status of
+ *     all devices.
+ *	 0x01: PCICA
+ *	 0x02: PCICC
+ *	 0x03: PCIXCC_MCL2
+ *	 0x04: PCIXCC_MCL3
+ *	 0x05: CEX2C
+ *	 0x06: CEX2A
+ *	 0x0d: device is disabled via the proc filesystem
+ *
+ *   Z90STAT_QDEPTH_MASK
+ *     Return an 64 element array of unsigned chars for the queue
+ *     depth of all devices.
+ *
+ *   Z90STAT_PERDEV_REQCNT
+ *     Return an 64 element array of unsigned integers for the number
+ *     of successfully completed requests per device since the device
+ *     was detected and made available.
+ *
+ *   ICAZ90STATUS (deprecated)
+ *     Return some device driver status in a ica_z90_status struct
+ *     This takes an ica_z90_status struct as its arg.
+ *
+ *     NOTE: this ioctl() is deprecated, and has been replaced with
+ *	     single ioctl()s for each type of status being requested
+ *
+ *   Z90STAT_PCIXCCCOUNT (deprecated)
+ *     Return an integer count of all PCIXCCs (MCL2 + MCL3).
+ *     This is DEPRECATED now that MCL3 PCIXCCs are treated differently from
+ *     MCL2 PCIXCCs.
+ *
+ *   Z90QUIESCE (not recommended)
+ *     Quiesce the driver.  This is intended to stop all new
+ *     requests from being processed.  Its use is NOT recommended,
+ *     except in circumstances where there is no other way to stop
+ *     callers from accessing the driver.  Its original use was to
+ *     allow the driver to be "drained" of work in preparation for
+ *     a system shutdown.
+ *
+ *     NOTE: once issued, this ban on new work cannot be undone
+ *	     except by unloading and reloading the driver.
+ */
+
+/**
+ * Supported ioctl calls
+ */
+#define ICARSAMODEXPO	_IOC(_IOC_READ|_IOC_WRITE, ZCRYPT_IOCTL_MAGIC, 0x05, 0)
+#define ICARSACRT	_IOC(_IOC_READ|_IOC_WRITE, ZCRYPT_IOCTL_MAGIC, 0x06, 0)
+
+/* New status calls */
+#define Z90STAT_TOTALCOUNT	_IOR(ZCRYPT_IOCTL_MAGIC, 0x40, int)
+#define Z90STAT_PCICACOUNT	_IOR(ZCRYPT_IOCTL_MAGIC, 0x41, int)
+#define Z90STAT_PCICCCOUNT	_IOR(ZCRYPT_IOCTL_MAGIC, 0x42, int)
+#define Z90STAT_PCIXCCMCL2COUNT	_IOR(ZCRYPT_IOCTL_MAGIC, 0x4b, int)
+#define Z90STAT_PCIXCCMCL3COUNT	_IOR(ZCRYPT_IOCTL_MAGIC, 0x4c, int)
+#define Z90STAT_CEX2CCOUNT	_IOR(ZCRYPT_IOCTL_MAGIC, 0x4d, int)
+#define Z90STAT_CEX2ACOUNT	_IOR(ZCRYPT_IOCTL_MAGIC, 0x4e, int)
+#define Z90STAT_REQUESTQ_COUNT	_IOR(ZCRYPT_IOCTL_MAGIC, 0x44, int)
+#define Z90STAT_PENDINGQ_COUNT	_IOR(ZCRYPT_IOCTL_MAGIC, 0x45, int)
+#define Z90STAT_TOTALOPEN_COUNT _IOR(ZCRYPT_IOCTL_MAGIC, 0x46, int)
+#define Z90STAT_DOMAIN_INDEX	_IOR(ZCRYPT_IOCTL_MAGIC, 0x47, int)
+#define Z90STAT_STATUS_MASK	_IOR(ZCRYPT_IOCTL_MAGIC, 0x48, char[64])
+#define Z90STAT_QDEPTH_MASK	_IOR(ZCRYPT_IOCTL_MAGIC, 0x49, char[64])
+#define Z90STAT_PERDEV_REQCNT	_IOR(ZCRYPT_IOCTL_MAGIC, 0x4a, int[64])
+
+#endif /* __ASM_S390_ZCRYPT_H */