[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>

1 files changed, 50 insertions, 3 deletions

diff --git a/drivers/s390/char/tape_core.c b/drivers/s390/char/tape_core.c
index c6c2e918b990..8691bb985d00 100644
--- a/drivers/s390/char/tape_core.c
+++ b/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)