[kvm-unit-tests PATCH v5 2/2] s390x: sclp: Implement extended-length-SCCB facility

[Pierre Morel <pmorel@linux.ibm.com>]

When the extended-length-SCCB facility is present use a big
buffer already at first try when calling sclp_read_scp_info()
to avoid the SCLP_RC_INSUFFICIENT_SCCB_LENGTH error.

Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
---
 lib/s390x/sclp.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/lib/s390x/sclp.c b/lib/s390x/sclp.c
index adf357b..e44d299 100644
--- a/lib/s390x/sclp.c
+++ b/lib/s390x/sclp.c
@@ -17,13 +17,14 @@
 #include "sclp.h"
 #include <alloc_phys.h>
 #include <alloc_page.h>
+#include <asm/facility.h>
 
 extern unsigned long stacktop;
 
 static uint64_t storage_increment_size;
 static uint64_t max_ram_size;
 static uint64_t ram_size;
-char _read_info[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE)));
+char _read_info[2 * PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE)));
 static ReadInfo *read_info;
 struct sclp_facilities sclp_facilities;
 
@@ -114,6 +115,8 @@ static void sclp_read_scp_info(ReadInfo *ri, int length)
 void sclp_read_info(void)
 {
 	sclp_read_scp_info((void *)_read_info, SCCB_SIZE);
+	sclp_read_scp_info((void *)_read_info,
+		test_facility(140) ? sizeof(_read_info) : SCCB_SIZE);
 	read_info = (ReadInfo *)_read_info;
 }
 
-- 
2.31.1