1 files changed, 38 insertions, 0 deletions
diff --git a/arch/s390/kernel/ipl_vmparm.c b/arch/s390/kernel/ipl_vmparm.c
new file mode 100644
index 000000000..b5245fadc
--- /dev/null
+++ b/arch/s390/kernel/ipl_vmparm.c
@@ -0,0 +1,38 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/minmax.h>
+#include <linux/string.h>
+#include <asm/ebcdic.h>
+#include <asm/ipl.h>
+
+/* VM IPL PARM routines */
+size_t ipl_block_get_ascii_vmparm(char *dest, size_t size,
+				  const struct ipl_parameter_block *ipb)
+{
+	int i;
+	size_t len;
+	char has_lowercase = 0;
+
+	len = 0;
+	if ((ipb->ccw.vm_flags & IPL_PB0_CCW_VM_FLAG_VP) &&
+	    (ipb->ccw.vm_parm_len > 0)) {
+
+		len = min_t(size_t, size - 1, ipb->ccw.vm_parm_len);
+		memcpy(dest, ipb->ccw.vm_parm, len);
+		/* If at least one character is lowercase, we assume mixed
+		 * case; otherwise we convert everything to lowercase.
+		 */
+		for (i = 0; i < len; i++)
+			if ((dest[i] > 0x80 && dest[i] < 0x8a) || /* a-i */
+			    (dest[i] > 0x90 && dest[i] < 0x9a) || /* j-r */
+			    (dest[i] > 0xa1 && dest[i] < 0xaa)) { /* s-z */
+				has_lowercase = 1;
+				break;
+			}
+		if (!has_lowercase)
+			EBC_TOLOWER(dest, len);
+		EBCASC(dest, len);
+	}
+	dest[len] = 0;
+
+	return len;
+}