From: Harald Freudenberger <freude@linux.ibm.com>
Subject: s390/zcrypt: fix ap_instructions_available() returncodes
Patch-mainline: v4.19-rc1
Git-commit: 2395103b3fbf2553d94a64ac3e29595cb040474b
References: FATE#325689, LTC#167899, bsc#1113520
Summary: zcrypt: AP bus support for alternate driver(s)
Description: AP bus support for alternate driver(s) and deterministic
driver binding. For details please read the patch header
for commit 7e0bdbe5c21cb8316a694e46ad5aad339f6894a6
Upstream-Description:
s390/zcrypt: fix ap_instructions_available() returncodes
During review of KVM patches it was complained that the
ap_instructions_available() function returns 0 if AP
instructions are available and -ENODEV if not. The function
acts like a boolean function to check for AP instructions
available and thus should return 0 on failure and != 0 on
success. Changed to the suggested behaviour and adapted
the one and only caller of this function which is the ap
bus core code.
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
arch/s390/include/asm/ap.h | 10 +++++-----
drivers/s390/crypto/ap_bus.c | 2 +-
2 files changed, 6 insertions(+), 6 deletions(-)
--- a/arch/s390/include/asm/ap.h
+++ b/arch/s390/include/asm/ap.h
@@ -52,20 +52,20 @@ struct ap_queue_status {
/**
* ap_intructions_available() - Test if AP instructions are available.
*
- * Returns 0 if the AP instructions are installed.
+ * Returns 1 if the AP instructions are installed, otherwise 0.
*/
static inline int ap_instructions_available(void)
{
register unsigned long reg0 asm ("0") = AP_MKQID(0, 0);
- register unsigned long reg1 asm ("1") = -ENODEV;
- register unsigned long reg2 asm ("2");
+ register unsigned long reg1 asm ("1") = 0;
+ register unsigned long reg2 asm ("2") = 0;
asm volatile(
" .long 0xb2af0000\n" /* PQAP(TAPQ) */
- "0: la %0,0\n"
+ "0: la %0,1\n"
"1:\n"
EX_TABLE(0b, 1b)
- : "+d" (reg1), "=d" (reg2)
+ : "+d" (reg1), "+d" (reg2)
: "d" (reg0)
: "cc");
return reg1;
--- a/drivers/s390/crypto/ap_bus.c
+++ b/drivers/s390/crypto/ap_bus.c
@@ -1239,7 +1239,7 @@ int __init ap_module_init(void)
if (rc)
return rc;
- if (ap_instructions_available() != 0) {
+ if (!ap_instructions_available()) {
pr_warn("The hardware system does not support AP instructions\n");
return -ENODEV;
}