[S390] Inline assembly cleanup.

Major cleanup of all s390 inline assemblies. They now have a common
coding style. Quite a few have been shortened, mainly by using register
asm variables. Use of the EX_TABLE macro helps  as well. The atomic ops,
bit ops and locking inlines new use the Q-constraint if a newer gcc
is used.  That results in slightly better code.

Thanks to Christian Borntraeger for proof reading the changes.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 30 insertions, 53 deletions

diff --git a/arch/s390/kernel/cpcmd.c b/arch/s390/kernel/cpcmd.c
index 4ef44e536b2..1eae74e72f9 100644
--- a/arch/s390/kernel/cpcmd.c
+++ b/arch/s390/kernel/cpcmd.c
@@ -25,11 +25,8 @@ static char cpcmd_buf[241];
  */
 int  __cpcmd(const char *cmd, char *response, int rlen, int *response_code)
 {
-	const int mask = 0x40000000L;
-	unsigned long flags;
-	int return_code;
-	int return_len;
-	int cmdlen;
+	unsigned long flags, cmdlen;
+	int return_code, return_len;
 
 	spin_lock_irqsave(&cpcmd_lock, flags);
 	cmdlen = strlen(cmd);
@@ -38,64 +35,44 @@ int  __cpcmd(const char *cmd, char *response, int rlen, int *response_code)
 	ASCEBC(cpcmd_buf, cmdlen);
 
 	if (response != NULL && rlen > 0) {
+		register unsigned long reg2 asm ("2") = (addr_t) cpcmd_buf;
+		register unsigned long reg3 asm ("3") = (addr_t) response;
+		register unsigned long reg4 asm ("4") = cmdlen | 0x40000000L;
+		register unsigned long reg5 asm ("5") = rlen;
+
 		memset(response, 0, rlen);
+		asm volatile(
 #ifndef CONFIG_64BIT
-		asm volatile (	"lra	2,0(%2)\n"
-				"lr	4,%3\n"
-				"o	4,%6\n"
-				"lra	3,0(%4)\n"
-				"lr	5,%5\n"
-				"diag	2,4,0x8\n"
-				"brc	8, 1f\n"
-				"ar	5, %5\n"
-				"1: \n"
-				"lr	%0,4\n"
-				"lr	%1,5\n"
-				: "=d" (return_code), "=d" (return_len)
-				: "a" (cpcmd_buf), "d" (cmdlen),
-				"a" (response), "d" (rlen), "m" (mask)
-				: "cc", "2", "3", "4", "5" );
+			"	diag	%2,%0,0x8\n"
+			"	brc	8,1f\n"
+			"	ar	%1,%4\n"
 #else /* CONFIG_64BIT */
-                asm volatile (	"lrag	2,0(%2)\n"
-				"lgr	4,%3\n"
-				"o	4,%6\n"
-				"lrag	3,0(%4)\n"
-				"lgr	5,%5\n"
-				"sam31\n"
-				"diag	2,4,0x8\n"
-				"sam64\n"
-				"brc	8, 1f\n"
-				"agr	5, %5\n"
-				"1: \n"
-				"lgr	%0,4\n"
-				"lgr	%1,5\n"
-				: "=d" (return_code), "=d" (return_len)
-				: "a" (cpcmd_buf), "d" (cmdlen),
-				"a" (response), "d" (rlen), "m" (mask)
-				: "cc", "2", "3", "4", "5" );
+			"	sam31\n"
+			"	diag	%2,%0,0x8\n"
+			"	sam64\n"
+			"	brc	8,1f\n"
+			"	agr	%1,%4\n"
 #endif /* CONFIG_64BIT */
+			"1:\n"
+			: "+d" (reg4), "+d" (reg5)
+			: "d" (reg2), "d" (reg3), "d" (rlen) : "cc");
+		return_code = (int) reg4;
+		return_len = (int) reg5;
                 EBCASC(response, rlen);
         } else {
+		register unsigned long reg2 asm ("2") = (addr_t) cpcmd_buf;
+		register unsigned long reg3 asm ("3") = cmdlen;
 		return_len = 0;
+		asm volatile(
 #ifndef CONFIG_64BIT
-                asm volatile (	"lra	2,0(%1)\n"
-				"lr	3,%2\n"
-				"diag	2,3,0x8\n"
-				"lr	%0,3\n"
-				: "=d" (return_code)
-				: "a" (cpcmd_buf), "d" (cmdlen)
-				: "2", "3"  );
+			"	diag	%1,%0,0x8\n"
 #else /* CONFIG_64BIT */
-                asm volatile (	"lrag	2,0(%1)\n"
-				"lgr	3,%2\n"
-				"sam31\n"
-				"diag	2,3,0x8\n"
-				"sam64\n"
-				"lgr	%0,3\n"
-				: "=d" (return_code)
-				: "a" (cpcmd_buf), "d" (cmdlen)
-				: "2", "3" );
+			"	sam31\n"
+			"	diag	%1,%0,0x8\n"
+			"	sam64\n"
 #endif /* CONFIG_64BIT */
+			: "+d" (reg3) : "d" (reg2) : "cc");
+		return_code = (int) reg3;
         }
 	spin_unlock_irqrestore(&cpcmd_lock, flags);
 	if (response_code != NULL)