s390/ptrace: add struct psw and accessor function

Introduce a 'struct psw' which makes it easier to decode and test if
certain bits in a psw are set or are not set.
In addition also add a 'psw_bits()' helper define which allows to
directly modify and test a psw_t structure. E.g.

psw_t psw;
psw_bits(psw).t = 1; /* set dat bit */

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

1 files changed, 44 insertions, 0 deletions

diff --git a/arch/s390/include/asm/ptrace.h b/arch/s390/include/asm/ptrace.h
index f4783c0b7b43..6e7708f3d866 100644
--- a/arch/s390/include/asm/ptrace.h
+++ b/arch/s390/include/asm/ptrace.h
@@ -16,6 +16,50 @@
                          PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_MASK_MCHECK | \
                          PSW_MASK_PSTATE | PSW_ASC_PRIMARY)
 
+struct psw_bits {
+        unsigned long long      : 1;
+        unsigned long long r    : 1; /* PER-Mask */
+        unsigned long long      : 3;
+        unsigned long long t    : 1; /* DAT Mode */
+        unsigned long long i    : 1; /* Input/Output Mask */
+        unsigned long long e    : 1; /* External Mask */
+        unsigned long long key  : 4; /* PSW Key */
+        unsigned long long      : 1;
+        unsigned long long m    : 1; /* Machine-Check Mask */
+        unsigned long long w    : 1; /* Wait State */
+        unsigned long long p    : 1; /* Problem State */
+        unsigned long long as   : 2; /* Address Space Control */
+        unsigned long long cc   : 2; /* Condition Code */
+        unsigned long long pm   : 4; /* Program Mask */
+        unsigned long long ri   : 1; /* Runtime Instrumentation */
+        unsigned long long      : 6;
+        unsigned long long eaba : 2; /* Addressing Mode */
+#ifdef CONFIG_64BIT
+        unsigned long long      : 31;
+        unsigned long long ia   : 64;/* Instruction Address */
+#else
+        unsigned long long ia   : 31;/* Instruction Address */
+#endif
+};
+
+enum {
+        PSW_AMODE_24BIT = 0,
+        PSW_AMODE_31BIT = 1,
+        PSW_AMODE_64BIT = 3
+};
+
+enum {
+        PSW_AS_PRIMARY   = 0,
+        PSW_AS_ACCREG    = 1,
+        PSW_AS_SECONDARY = 2,
+        PSW_AS_HOME      = 3
+};
+
+#define psw_bits(__psw) (*({                    \
+        typecheck(psw_t, __psw);                \
+        &(*(struct psw_bits *)(&(__psw)));      \
+}))
+
 /*
  * The pt_regs struct defines the way the registers are stored on
  * the stack during a system call.