5 files changed, 120 insertions, 37 deletions

diff --git a/drivers/s390/block/xpram.c b/drivers/s390/block/xpram.c
index c881a14fa5dd..1f6a4d894e73 100644
--- a/drivers/s390/block/xpram.c
+++ b/drivers/s390/block/xpram.c
@@ -62,8 +62,8 @@ static int xpram_devs;
 /*
  * Parameter parsing functions.
  */
-static int __initdata devs = XPRAM_DEVS;
-static char __initdata *sizes[XPRAM_MAX_DEVS];
+static int devs = XPRAM_DEVS;
+static char *sizes[XPRAM_MAX_DEVS];
 
 module_param(devs, int, 0);
 module_param_array(sizes, charp, NULL, 0);
diff --git a/drivers/s390/char/keyboard.c b/drivers/s390/char/keyboard.c
index 8cd58e412b5e..5ad44daef73b 100644
--- a/drivers/s390/char/keyboard.c
+++ b/drivers/s390/char/keyboard.c
@@ -460,7 +460,8 @@ kbd_ioctl(struct kbd_data *kbd, struct file *file,
           unsigned int cmd, unsigned long arg)
 {
         void __user *argp;
-        int ct, perm;
+        unsigned int ct;
+        int perm;
 
         argp = (void __user *)arg;
 
diff --git a/drivers/s390/char/tape.h b/drivers/s390/char/tape.h
index 7a242f073632..267b54e8ff5a 100644
--- a/drivers/s390/char/tape.h
+++ b/drivers/s390/char/tape.h
@@ -280,6 +280,14 @@ tape_do_io_free(struct tape_device *device, struct tape_request *request)
         return rc;
 }
 
+static inline void
+tape_do_io_async_free(struct tape_device *device, struct tape_request *request)
+{
+        request->callback = (void *) tape_free_request;
+        request->callback_data = NULL;
+        tape_do_io_async(device, request);
+}
+
 extern int tape_oper_handler(int irq, int status);
 extern void tape_noper_handler(int irq, int status);
 extern int tape_open(struct tape_device *);
diff --git a/drivers/s390/char/tape_34xx.c b/drivers/s390/char/tape_34xx.c
index c17f35b6136a..c26511171ffe 100644
--- a/drivers/s390/char/tape_34xx.c
+++ b/drivers/s390/char/tape_34xx.c
@@ -53,23 +53,11 @@ static void tape_34xx_delete_sbid_from(struct tape_device *, int);
  * Medium sense for 34xx tapes. There is no 'real' medium sense call.
  * So we just do a normal sense.
  */
-static int
-tape_34xx_medium_sense(struct tape_device *device)
+static void __tape_34xx_medium_sense(struct tape_request *request)
 {
-        struct tape_request *request;
-        unsigned char       *sense;
-        int                  rc;
-
-        request = tape_alloc_request(1, 32);
-        if (IS_ERR(request)) {
-                DBF_EXCEPTION(6, "MSEN fail\n");
-                return PTR_ERR(request);
-        }
-
-        request->op = TO_MSEN;
-        tape_ccw_end(request->cpaddr, SENSE, 32, request->cpdata);
+        struct tape_device *device = request->device;
+        unsigned char *sense;
 
-        rc = tape_do_io_interruptible(device, request);
         if (request->rc == 0) {
                 sense = request->cpdata;
 
@@ -88,15 +76,47 @@ tape_34xx_medium_sense(struct tape_device *device)
                         device->tape_generic_status |= GMT_WR_PROT(~0);
                 else
                         device->tape_generic_status &= ~GMT_WR_PROT(~0);
-        } else {
+        } else
                 DBF_EVENT(4, "tape_34xx: medium sense failed with rc=%d\n",
                         request->rc);
-        }
         tape_free_request(request);
+}
+
+static int tape_34xx_medium_sense(struct tape_device *device)
+{
+        struct tape_request *request;
+        int rc;
+
+        request = tape_alloc_request(1, 32);
+        if (IS_ERR(request)) {
+                DBF_EXCEPTION(6, "MSEN fail\n");
+                return PTR_ERR(request);
+        }
 
+        request->op = TO_MSEN;
+        tape_ccw_end(request->cpaddr, SENSE, 32, request->cpdata);
+        rc = tape_do_io_interruptible(device, request);
+        __tape_34xx_medium_sense(request);
         return rc;
 }
 
+static void tape_34xx_medium_sense_async(struct tape_device *device)
+{
+        struct tape_request *request;
+
+        request = tape_alloc_request(1, 32);
+        if (IS_ERR(request)) {
+                DBF_EXCEPTION(6, "MSEN fail\n");
+                return;
+        }
+
+        request->op = TO_MSEN;
+        tape_ccw_end(request->cpaddr, SENSE, 32, request->cpdata);
+        request->callback = (void *) __tape_34xx_medium_sense;
+        request->callback_data = NULL;
+        tape_do_io_async(device, request);
+}
+
 struct tape_34xx_work {
         struct tape_device      *device;
         enum tape_op             op;
@@ -109,6 +129,9 @@ struct tape_34xx_work {
  * is inserted but cannot call tape_do_io* from an interrupt context.
  * Maybe that's useful for other actions we want to start from the
  * interrupt handler.
+ * Note: the work handler is called by the system work queue. The tape
+ * commands started by the handler need to be asynchrounous, otherwise
+ * a deadlock can occur e.g. in case of a deferred cc=1 (see __tape_do_irq).
  */
 static void
 tape_34xx_work_handler(struct work_struct *work)
@@ -119,7 +142,7 @@ tape_34xx_work_handler(struct work_struct *work)
 
         switch(p->op) {
                 case TO_MSEN:
-                        tape_34xx_medium_sense(device);
+                        tape_34xx_medium_sense_async(device);
                         break;
                 default:
                         DBF_EVENT(3, "T34XX: internal error: unknown work\n");
diff --git a/drivers/s390/char/tape_3590.c b/drivers/s390/char/tape_3590.c
index fbe361fcd2c0..de2e99e0a71b 100644
--- a/drivers/s390/char/tape_3590.c
+++ b/drivers/s390/char/tape_3590.c
@@ -329,17 +329,17 @@ out:
 /*
  * Enable encryption
  */
-static int tape_3592_enable_crypt(struct tape_device *device)
+static struct tape_request *__tape_3592_enable_crypt(struct tape_device *device)
 {
         struct tape_request *request;
         char *data;
 
         DBF_EVENT(6, "tape_3592_enable_crypt\n");
         if (!crypt_supported(device))
-                return -ENOSYS;
+                return ERR_PTR(-ENOSYS);
         request = tape_alloc_request(2, 72);
         if (IS_ERR(request))
-                return PTR_ERR(request);
+                return request;
         data = request->cpdata;
         memset(data,0,72);
 
@@ -354,23 +354,42 @@ static int tape_3592_enable_crypt(struct tape_device *device)
         request->op = TO_CRYPT_ON;
         tape_ccw_cc(request->cpaddr, MODE_SET_CB, 36, data);
         tape_ccw_end(request->cpaddr + 1, MODE_SET_CB, 36, data + 36);
+        return request;
+}
+
+static int tape_3592_enable_crypt(struct tape_device *device)
+{
+        struct tape_request *request;
+
+        request = __tape_3592_enable_crypt(device);
+        if (IS_ERR(request))
+                return PTR_ERR(request);
         return tape_do_io_free(device, request);
 }
 
+static void tape_3592_enable_crypt_async(struct tape_device *device)
+{
+        struct tape_request *request;
+
+        request = __tape_3592_enable_crypt(device);
+        if (!IS_ERR(request))
+                tape_do_io_async_free(device, request);
+}
+
 /*
  * Disable encryption
  */
-static int tape_3592_disable_crypt(struct tape_device *device)
+static struct tape_request *__tape_3592_disable_crypt(struct tape_device *device)
 {
         struct tape_request *request;
         char *data;
 
         DBF_EVENT(6, "tape_3592_disable_crypt\n");
         if (!crypt_supported(device))
-                return -ENOSYS;
+                return ERR_PTR(-ENOSYS);
         request = tape_alloc_request(2, 72);
         if (IS_ERR(request))
-                return PTR_ERR(request);
+                return request;
         data = request->cpdata;
         memset(data,0,72);
 
@@ -383,9 +402,28 @@ static int tape_3592_disable_crypt(struct tape_device *device)
         tape_ccw_cc(request->cpaddr, MODE_SET_CB, 36, data);
         tape_ccw_end(request->cpaddr + 1, MODE_SET_CB, 36, data + 36);
 
+        return request;
+}
+
+static int tape_3592_disable_crypt(struct tape_device *device)
+{
+        struct tape_request *request;
+
+        request = __tape_3592_disable_crypt(device);
+        if (IS_ERR(request))
+                return PTR_ERR(request);
         return tape_do_io_free(device, request);
 }
 
+static void tape_3592_disable_crypt_async(struct tape_device *device)
+{
+        struct tape_request *request;
+
+        request = __tape_3592_disable_crypt(device);
+        if (!IS_ERR(request))
+                tape_do_io_async_free(device, request);
+}
+
 /*
  * IOCTL: Set encryption status
  */
@@ -457,8 +495,7 @@ tape_3590_ioctl(struct tape_device *device, unsigned int cmd, unsigned long arg)
 /*
  * SENSE Medium: Get Sense data about medium state
  */
-static int
-tape_3590_sense_medium(struct tape_device *device)
+static int tape_3590_sense_medium(struct tape_device *device)
 {
         struct tape_request *request;
 
@@ -470,6 +507,18 @@ tape_3590_sense_medium(struct tape_device *device)
         return tape_do_io_free(device, request);
 }
 
+static void tape_3590_sense_medium_async(struct tape_device *device)
+{
+        struct tape_request *request;
+
+        request = tape_alloc_request(1, 128);
+        if (IS_ERR(request))
+                return;
+        request->op = TO_MSEN;
+        tape_ccw_end(request->cpaddr, MEDIUM_SENSE, 128, request->cpdata);
+        tape_do_io_async_free(device, request);
+}
+
 /*
  * MTTELL: Tell block. Return the number of block relative to current file.
  */
@@ -546,15 +595,14 @@ tape_3590_read_opposite(struct tape_device *device,
  * 2. The attention msg is written to the "read subsystem data" buffer.
  * In this case we probably should print it to the console.
  */
-static int
-tape_3590_read_attmsg(struct tape_device *device)
+static void tape_3590_read_attmsg_async(struct tape_device *device)
 {
         struct tape_request *request;
         char *buf;
 
         request = tape_alloc_request(3, 4096);
         if (IS_ERR(request))
-                return PTR_ERR(request);
+                return;
         request->op = TO_READ_ATTMSG;
         buf = request->cpdata;
         buf[0] = PREP_RD_SS_DATA;
@@ -562,12 +610,15 @@ tape_3590_read_attmsg(struct tape_device *device)
         tape_ccw_cc(request->cpaddr, PERFORM_SS_FUNC, 12, buf);
         tape_ccw_cc(request->cpaddr + 1, READ_SS_DATA, 4096 - 12, buf + 12);
         tape_ccw_end(request->cpaddr + 2, NOP, 0, NULL);
-        return tape_do_io_free(device, request);
+        tape_do_io_async_free(device, request);
 }
 
 /*
  * These functions are used to schedule follow-up actions from within an
  * interrupt context (like unsolicited interrupts).
+ * Note: the work handler is called by the system work queue. The tape
+ * commands started by the handler need to be asynchrounous, otherwise
+ * a deadlock can occur e.g. in case of a deferred cc=1 (see __tape_do_irq).
  */
 struct work_handler_data {
         struct tape_device *device;
@@ -583,16 +634,16 @@ tape_3590_work_handler(struct work_struct *work)
 
         switch (p->op) {
         case TO_MSEN:
-                tape_3590_sense_medium(p->device);
+                tape_3590_sense_medium_async(p->device);
                 break;
         case TO_READ_ATTMSG:
-                tape_3590_read_attmsg(p->device);
+                tape_3590_read_attmsg_async(p->device);
                 break;
         case TO_CRYPT_ON:
-                tape_3592_enable_crypt(p->device);
+                tape_3592_enable_crypt_async(p->device);
                 break;
         case TO_CRYPT_OFF:
-                tape_3592_disable_crypt(p->device);
+                tape_3592_disable_crypt_async(p->device);
                 break;
         default:
                 DBF_EVENT(3, "T3590: work handler undefined for "