[S390] Add crypto support for 3592 tape devices

3592 tape devices are able to write data encrpyted on tape mediums.
This z/Linux device driver support includes the following functions:
 * ioctl to switch on/off encryption
 * ioctl to query encryption status of drive
 * ioctls to set and query key encrypting keys (kekls)
 * long busy interrupt handling
Signed-off-by: Michael Holzheu <holzheu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

drivers/s390/char/tape.h

@@ -3,7 +3,7 @@
  *    tape device driver for 3480/3490E/3590 tapes.
  *
  *  S390 and zSeries version
- *    Copyright (C) 2001,2005 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ *    Copyright IBM Corp. 2001,2006
  *    Author(s): Carsten Otte <cotte@de.ibm.com>
  *		 Tuan Ngo-Anh <ngoanh@de.ibm.com>
  *		 Martin Schwidefsky <schwidefsky@de.ibm.com>
@@ -99,7 +99,11 @@ enum tape_op {
 	TO_DIS,		/* Tape display */
 	TO_ASSIGN,	/* Assign tape to channel path */
 	TO_UNASSIGN,	/* Unassign tape from channel path */
-	TO_SIZE		/* #entries in tape_op_t */
+	TO_CRYPT_ON,	/* Enable encrpytion */
+	TO_CRYPT_OFF,	/* Disable encrpytion */
+	TO_KEKL_SET,	/* Set KEK label */
+	TO_KEKL_QUERY,	/* Query KEK label */
+	TO_SIZE,	/* #entries in tape_op_t */
 };
 
 /* Forward declaration */
@@ -112,6 +116,7 @@ enum tape_request_status {
 	TAPE_REQUEST_IN_IO,	/* request is currently in IO */
 	TAPE_REQUEST_DONE,	/* request is completed. */
 	TAPE_REQUEST_CANCEL,	/* request should be canceled. */
+	TAPE_REQUEST_LONG_BUSY, /* request has to be restarted after long busy */
 };
 
 /* Tape CCW request */
@@ -164,10 +169,11 @@ struct tape_discipline {
  * The discipline irq function either returns an error code (<0) which
  * means that the request has failed with an error or one of the following:
  */
-#define TAPE_IO_SUCCESS 0	/* request successful */
-#define TAPE_IO_PENDING 1	/* request still running */
-#define TAPE_IO_RETRY	2	/* retry to current request */
-#define TAPE_IO_STOP	3	/* stop the running request */
+#define TAPE_IO_SUCCESS		0	/* request successful */
+#define TAPE_IO_PENDING		1	/* request still running */
+#define TAPE_IO_RETRY		2	/* retry to current request */
+#define TAPE_IO_STOP		3	/* stop the running request */
+#define TAPE_IO_LONG_BUSY	4	/* delay the running request */
 
 /* Char Frontend Data */
 struct tape_char_data {
@@ -242,6 +248,10 @@ struct tape_device {
 
 	/* Function to start or stop the next request later. */
 	struct delayed_work		tape_dnr;
+
+	/* Timer for long busy */
+	struct timer_list		lb_timeout;
+
 };
 
 /* Externals from tape_core.c */

drivers/s390/char/tape_3590.h

@@ -2,7 +2,7 @@
  *  drivers/s390/char/tape_3590.h
  *    tape device discipline for 3590 tapes.
  *
- *    Copyright (C) IBM Corp. 2001,2006
+ *    Copyright IBM Corp. 2001,2006
  *    Author(s): Stefan Bader <shbader@de.ibm.com>
  *		 Michael Holzheu <holzheu@de.ibm.com>
  *		 Martin Schwidefsky <schwidefsky@de.ibm.com>
@@ -38,16 +38,22 @@
 #define MSENSE_UNASSOCIATED	 0x00
 #define MSENSE_ASSOCIATED_MOUNT	 0x01
 #define MSENSE_ASSOCIATED_UMOUNT 0x02
+#define MSENSE_CRYPT_MASK	 0x00000010
 
 #define TAPE_3590_MAX_MSG	 0xb0
 
 /* Datatypes */
 
 struct tape_3590_disc_data {
-	unsigned char modeset_byte;
+	struct tape390_crypt_info crypt_info;
 	int read_back_op;
 };
 
+#define TAPE_3590_CRYPT_INFO(device) \
+	((struct tape_3590_disc_data*)(device->discdata))->crypt_info
+#define TAPE_3590_READ_BACK_OP(device) \
+	((struct tape_3590_disc_data*)(device->discdata))->read_back_op
+
 struct tape_3590_sense {
 
 	unsigned int command_rej:1;
@@ -118,7 +124,48 @@ struct tape_3590_sense {
 struct tape_3590_med_sense {
 	unsigned int macst:4;
 	unsigned int masst:4;
-	char pad[127];
+	char pad1[7];
+	unsigned int flags;
+	char pad2[116];
+} __attribute__ ((packed));
+
+/* Datastructures for 3592 encryption support */
+
+struct tape3592_kekl {
+	__u8 flags;
+	char label[64];
+} __attribute__ ((packed));
+
+struct tape3592_kekl_pair {
+	__u8 count;
+	struct tape3592_kekl kekl[2];
+} __attribute__ ((packed));
+
+struct tape3592_kekl_query_data {
+	__u16 len;
+	__u8  fmt;
+	__u8  mc;
+	__u32 id;
+	__u8  flags;
+	struct tape3592_kekl_pair kekls;
+	char reserved[116];
+} __attribute__ ((packed));
+
+struct tape3592_kekl_query_order {
+	__u8 code;
+	__u8 flags;
+	char reserved1[2];
+	__u8 max_count;
+	char reserved2[35];
+} __attribute__ ((packed));
+
+struct tape3592_kekl_set_order {
+	__u8 code;
+	__u8 flags;
+	char reserved1[2];
+	__u8 op;
+	struct tape3592_kekl_pair kekls;
+	char reserved2[120];
 } __attribute__ ((packed));
 
 #endif /* _TAPE_3590_H */

drivers/s390/char/tape_char.c

@@ -3,7 +3,7 @@
  *    character device frontend for tape device driver
  *
  *  S390 and zSeries version
- *    Copyright (C) 2001,2002 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ *    Copyright IBM Corp. 2001,2006
  *    Author(s): Carsten Otte <cotte@de.ibm.com>
  *		 Michael Holzheu <holzheu@de.ibm.com>
  *		 Tuan Ngo-Anh <ngoanh@de.ibm.com>

drivers/s390/char/tape_core.c

@@ -3,7 +3,7 @@
  *    basic function of the tape device driver
  *
  *  S390 and zSeries version
- *    Copyright (C) 2001,2005 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ *    Copyright IBM Corp. 2001,2006
  *    Author(s): Carsten Otte <cotte@de.ibm.com>
  *		 Michael Holzheu <holzheu@de.ibm.com>
  *		 Tuan Ngo-Anh <ngoanh@de.ibm.com>
@@ -26,9 +26,11 @@
 #include "tape_std.h"
 
 #define PRINTK_HEADER "TAPE_CORE: "
+#define LONG_BUSY_TIMEOUT 180 /* seconds */
 
 static void __tape_do_irq (struct ccw_device *, unsigned long, struct irb *);
 static void tape_delayed_next_request(struct work_struct *);
+static void tape_long_busy_timeout(unsigned long data);
 
 /*
  * One list to contain all tape devices of all disciplines, so
@@ -69,7 +71,9 @@ const char *tape_op_verbose[TO_SIZE] =
 	[TO_LOAD] = "LOA",	[TO_READ_CONFIG] = "RCF",
 	[TO_READ_ATTMSG] = "RAT",
 	[TO_DIS] = "DIS",	[TO_ASSIGN] = "ASS",
-	[TO_UNASSIGN] = "UAS"
+	[TO_UNASSIGN] = "UAS",  [TO_CRYPT_ON] = "CON",
+	[TO_CRYPT_OFF] = "COF",	[TO_KEKL_SET] = "KLS",
+	[TO_KEKL_QUERY] = "KLQ",
 };
 
 static inline int
@@ -346,6 +350,9 @@ tape_generic_online(struct tape_device *device,
 		return -EINVAL;
 	}
 
+	init_timer(&device->lb_timeout);
+	device->lb_timeout.function = tape_long_busy_timeout;
+
 	/* Let the discipline have a go at the device. */
 	device->discipline = discipline;
 	if (!try_module_get(discipline->owner)) {
@@ -801,6 +808,22 @@ tape_delayed_next_request(struct work_struct *work)
 	spin_unlock_irq(get_ccwdev_lock(device->cdev));
 }
 
+static void tape_long_busy_timeout(unsigned long data)
+{
+	struct tape_request *request;
+	struct tape_device *device;
+
+	device = (struct tape_device *) data;
+	spin_lock_irq(get_ccwdev_lock(device->cdev));
+	request = list_entry(device->req_queue.next, struct tape_request, list);
+	if (request->status != TAPE_REQUEST_LONG_BUSY)
+		BUG();
+	DBF_LH(6, "%08x: Long busy timeout.\n", device->cdev_id);
+	__tape_start_next_request(device);
+	device->lb_timeout.data = (unsigned long) tape_put_device(device);
+	spin_unlock_irq(get_ccwdev_lock(device->cdev));
+}
+
 static inline void
 __tape_end_request(
 	struct tape_device *	device,
@@ -1094,7 +1117,22 @@ __tape_do_irq (struct ccw_device *cdev, unsigned long intparm, struct irb *irb)
 	/* May be an unsolicited irq */
 	if(request != NULL)
 		request->rescnt = irb->scsw.count;
-
+	else if ((irb->scsw.dstat == 0x85 || irb->scsw.dstat == 0x80) &&
+		 !list_empty(&device->req_queue)) {
+		/* Not Ready to Ready after long busy ? */
+		struct tape_request *req;
+		req = list_entry(device->req_queue.next,
+				 struct tape_request, list);
+		if (req->status == TAPE_REQUEST_LONG_BUSY) {
+			DBF_EVENT(3, "(%08x): del timer\n", device->cdev_id);
+			if (del_timer(&device->lb_timeout)) {
+				device->lb_timeout.data = (unsigned long)
+					tape_put_device(device);
+				__tape_start_next_request(device);
+			}
+			return;
+		}
+	}
 	if (irb->scsw.dstat != 0x0c) {
 		/* Set the 'ONLINE' flag depending on sense byte 1 */
 		if(*(((__u8 *) irb->ecw) + 1) & SENSE_DRIVE_ONLINE)
@@ -1142,6 +1180,15 @@ __tape_do_irq (struct ccw_device *cdev, unsigned long intparm, struct irb *irb)
 			break;
 		case TAPE_IO_PENDING:
 			break;
+		case TAPE_IO_LONG_BUSY:
+			device->lb_timeout.data =
+				(unsigned long)tape_get_device_reference(device);
+			device->lb_timeout.expires = jiffies +
+				LONG_BUSY_TIMEOUT * HZ;
+			DBF_EVENT(3, "(%08x): add timer\n", device->cdev_id);
+			add_timer(&device->lb_timeout);
+			request->status = TAPE_REQUEST_LONG_BUSY;
+			break;
 		case TAPE_IO_RETRY:
 			rc = __tape_start_io(device, request);
 			if (rc)

include/asm-s390/tape390.h

 /*************************************************************************
  *
  * tape390.h
- *         enables user programs to display messages on the tape device
+ *	   enables user programs to display messages and control encryption
+ *	   on s390 tape devices
  *
- *  S390 and zSeries version
- *         Copyright (C) 2001 IBM Corporation
- *         Author(s): Despina Papadopoulou <despina_p@de.ibm.com>
+ *	   Copyright IBM Corp. 2001,2006
+ *	   Author(s): Michael Holzheu <holzheu@de.ibm.com>
  *
  *************************************************************************/
 
@@ -36,4 +36,68 @@ typedef struct display_struct {
         char message2[8];
 } display_struct;
 
+/*
+ * Tape encryption support
+ */
+
+struct tape390_crypt_info {
+	char capability;
+	char status;
+	char medium_status;
+} __attribute__ ((packed));
+
+
+/* Macros for "capable" field */
+#define TAPE390_CRYPT_SUPPORTED_MASK 0x01
+#define TAPE390_CRYPT_SUPPORTED(x) \
+	((x.capability & TAPE390_CRYPT_SUPPORTED_MASK))
+
+/* Macros for "status" field */
+#define TAPE390_CRYPT_ON_MASK 0x01
+#define TAPE390_CRYPT_ON(x) (((x.status) & TAPE390_CRYPT_ON_MASK))
+
+/* Macros for "medium status" field */
+#define TAPE390_MEDIUM_LOADED_MASK 0x01
+#define TAPE390_MEDIUM_ENCRYPTED_MASK 0x02
+#define TAPE390_MEDIUM_ENCRYPTED(x) \
+	(((x.medium_status) & TAPE390_MEDIUM_ENCRYPTED_MASK))
+#define TAPE390_MEDIUM_LOADED(x) \
+	(((x.medium_status) & TAPE390_MEDIUM_LOADED_MASK))
+
+/*
+ * The TAPE390_CRYPT_SET ioctl is used to switch on/off encryption.
+ * The "encryption_capable" and "tape_status" fields are ignored for this ioctl!
+ */
+#define TAPE390_CRYPT_SET _IOW('d', 2, struct tape390_crypt_info)
+
+/*
+ * The TAPE390_CRYPT_QUERY ioctl is used to query the encryption state.
+ */
+#define TAPE390_CRYPT_QUERY _IOR('d', 3, struct tape390_crypt_info)
+
+/* Values for "kekl1/2_type" and "kekl1/2_type_on_tape" fields */
+#define TAPE390_KEKL_TYPE_NONE 0
+#define TAPE390_KEKL_TYPE_LABEL 1
+#define TAPE390_KEKL_TYPE_HASH 2
+
+struct tape390_kekl {
+	unsigned char type;
+	unsigned char type_on_tape;
+	char label[65];
+} __attribute__ ((packed));
+
+struct tape390_kekl_pair {
+	struct tape390_kekl kekl[2];
+} __attribute__ ((packed));
+
+/*
+ * The TAPE390_KEKL_SET ioctl is used to set Key Encrypting Key labels.
+ */
+#define TAPE390_KEKL_SET _IOW('d', 4, struct tape390_kekl_pair)
+
+/*
+ * The TAPE390_KEKL_QUERY ioctl is used to query Key Encrypting Key labels.
+ */
+#define TAPE390_KEKL_QUERY _IOR('d', 5, struct tape390_kekl_pair)
+
 #endif