[RFC 3/8] s390x/pci: fix pcistb length

[Matthew Rosato <mjrosato@linux.ibm.com>]

In pcistb_service_call, we are grabbing 8 bits from a guest register to
indicate the length of the store operation -- but per the architecture
the length is actually defined by 13 bits of the guest register.

Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
---
 hw/s390x/s390-pci-inst.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/hw/s390x/s390-pci-inst.c b/hw/s390x/s390-pci-inst.c
index 70bfd91..db86f12 100644
--- a/hw/s390x/s390-pci-inst.c
+++ b/hw/s390x/s390-pci-inst.c
@@ -750,7 +750,7 @@ int pcistb_service_call(S390CPU *cpu, uint8_t r1, uint8_t r3, uint64_t gaddr,
     int i;
     uint32_t fh;
     uint8_t pcias;
-    uint8_t len;
+    uint16_t len;
     uint8_t buffer[128];
 
     if (env->psw.mask & PSW_MASK_PSTATE) {
@@ -760,7 +760,7 @@ int pcistb_service_call(S390CPU *cpu, uint8_t r1, uint8_t r3, uint64_t gaddr,
 
     fh = env->regs[r1] >> 32;
     pcias = (env->regs[r1] >> 16) & 0xf;
-    len = env->regs[r1] & 0xff;
+    len = env->regs[r1] & 0x1fff;
     offset = env->regs[r3];
 
     if (!(fh & FH_MASK_ENABLE)) {
-- 
1.8.3.1