s390: add struct tpi_info to struct pt_regs

To avoid casting ptrace members, add a union containing
both struct tpi_info and explicit int_code/int_parm members.

Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

arch/s390/include/asm/ptrace.h

@@ -9,6 +9,7 @@
 
 #include <linux/bits.h>
 #include <uapi/asm/ptrace.h>
+#include <asm/tpi.h>
 
 #define PIF_SYSCALL		0	/* inside a system call */
 #define PIF_SYSCALL_RESTART	1	/* restart the current system call */
@@ -86,9 +87,14 @@ struct pt_regs
 		};
 	};
 	unsigned long orig_gpr2;
-	unsigned int int_code;
-	unsigned int int_parm;
-	unsigned long int_parm_long;
+	union {
+		struct {
+			unsigned int int_code;
+			unsigned int int_parm;
+			unsigned long int_parm_long;
+		};
+		struct tpi_info tpi_info;
+	};
 	unsigned long flags;
 	unsigned long cr1;
 };

arch/s390/include/asm/tpi.h

@@ -5,6 +5,8 @@
 #include <linux/types.h>
 #include <uapi/asm/schid.h>
 
+#ifndef __ASSEMBLY__
+
 /* I/O-Interruption Code as stored by TEST PENDING INTERRUPTION (TPI). */
 struct tpi_info {
 	struct subchannel_id schid;
@@ -17,4 +19,6 @@ struct tpi_info {
 	u32 :12;
 } __packed __aligned(4);
 
+#endif /* __ASSEMBLY__ */
+
 #endif /* _ASM_S390_TPI_H */

arch/s390/include/uapi/asm/schid.h

@@ -4,6 +4,8 @@
 
 #include <linux/types.h>
 
+#ifndef __ASSEMBLY__
+
 struct subchannel_id {
 	__u32 cssid : 8;
 	__u32 : 4;
@@ -13,5 +15,6 @@ struct subchannel_id {
 	__u32 sch_no : 16;
 } __attribute__ ((packed, aligned(4)));
 
+#endif /* __ASSEMBLY__ */
 
 #endif /* _UAPIASM_SCHID_H */

drivers/s390/cio/airq.c

@@ -93,7 +93,7 @@ static irqreturn_t do_airq_interrupt(int irq, void *dummy)
 	struct hlist_head *head;
 
 	set_cpu_flag(CIF_NOHZ_DELAY);
-	tpi_info = (struct tpi_info *) &get_irq_regs()->int_code;
+	tpi_info = &get_irq_regs()->tpi_info;
 	trace_s390_cio_adapter_int(tpi_info);
 	head = &airq_lists[tpi_info->isc];
 	rcu_read_lock();

drivers/s390/cio/cio.c

@@ -536,7 +536,7 @@ static irqreturn_t do_cio_interrupt(int irq, void *dummy)
 	struct irb *irb;
 
 	set_cpu_flag(CIF_NOHZ_DELAY);
-	tpi_info = (struct tpi_info *) &get_irq_regs()->int_code;
+	tpi_info = &get_irq_regs()->tpi_info;
 	trace_s390_cio_interrupt(tpi_info);
 	irb = this_cpu_ptr(&cio_irb);
 	sch = (struct subchannel *)(unsigned long) tpi_info->intparm;