[S390] dasd: Work around gcc bug.

gcc incorrectly removes initialization of register 0 in dasd diag
inline assembly. Use different register to work around this compiler
bug.

Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

diff --git a/drivers/s390/block/dasd_diag.c b/drivers/s390/block/dasd_diag.c
index ab782bb..e810e4a 100644 (file)
--- a/drivers/s390/block/dasd_diag.c
+++ b/drivers/s390/block/dasd_diag.c
@@ -65,7 +65,7 @@ static const u8 DASD_DIAG_CMS1[] = { 0xc3, 0xd4, 0xe2, 0xf1 };/* EBCDIC CMS1 */
  * resulting condition code and DIAG return code. */
 static inline int dia250(void *iob, int cmd)
 {
-       register unsigned long reg0 asm ("0") = (unsigned long) iob;
+       register unsigned long reg2 asm ("2") = (unsigned long) iob;
        typedef union {
                struct dasd_diag_init_io init_io;
                struct dasd_diag_rw_io rw_io;
@@ -74,15 +74,15 @@ static inline int dia250(void *iob, int cmd)
 
        rc = 3;
        asm volatile(
-               "       diag    0,%2,0x250\n"
+               "       diag    2,%2,0x250\n"
                "0:     ipm     %0\n"
                "       srl     %0,28\n"
-               "       or      %0,1\n"
+               "       or      %0,3\n"
                "1:\n"
                EX_TABLE(0b,1b)
                : "+d" (rc), "=m" (*(addr_type *) iob)
-               : "d" (cmd), "d" (reg0), "m" (*(addr_type *) iob)
-               : "1", "cc");
+               : "d" (cmd), "d" (reg2), "m" (*(addr_type *) iob)
+               : "3", "cc");
        return rc;
 }