From 6faf4444f2445b068a4f75a86ae81b104c0eed2c Mon Sep 17 00:00:00 2001
From: Heiko Carstens <heiko.carstens@de.ibm.com>
Date: Tue, 9 Jan 2007 10:18:41 +0100
Subject: [PATCH] [S390] cio: use barrier() in stsch_reset.

Use barrier() in stsch_reset() instead of duplicating the stsch()
inline assembly and adding "memory" to the clobberlist.
Pointed out by Chuck Ebbert.

Real fix would be to add a fixup section to the stsch() and extend the
basic program check handler so it searches the exception tables in case
of a program check.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---
 drivers/s390/cio/cio.c | 12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/drivers/s390/cio/cio.c b/drivers/s390/cio/cio.c
index b471ac4a1bf66..ae1bf231d0894 100644
--- a/drivers/s390/cio/cio.c
+++ b/drivers/s390/cio/cio.c
@@ -880,19 +880,15 @@ static void cio_reset_pgm_check_handler(void)
 static int stsch_reset(struct subchannel_id schid, volatile struct schib *addr)
 {
 	int rc;
-	register struct subchannel_id reg1 asm ("1") = schid;
 
 	pgm_check_occured = 0;
 	s390_reset_pgm_handler = cio_reset_pgm_check_handler;
+	rc = stsch(schid, addr);
+	s390_reset_pgm_handler = NULL;
 
-	asm volatile(
-		"       stsch   0(%2)\n"
-		"       ipm     %0\n"
-		"       srl     %0,28"
-		: "=d" (rc)
-		: "d" (reg1), "a" (addr), "m" (*addr) : "memory", "cc");
+	/* The program check handler could have changed pgm_check_occured */
+	barrier();
 
-	s390_reset_pgm_handler = NULL;
 	if (pgm_check_occured)
 		return -EIO;
 	else
-- 
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