1// SPDX-License-Identifier: GPL-2.0
2#include <linux/minmax.h>
3#include <linux/string.h>
4#include <asm/ebcdic.h>
5#include <asm/ipl.h>
6
7/* VM IPL PARM routines */
8size_t ipl_block_get_ascii_vmparm(char *dest, size_t size,
9				  const struct ipl_parameter_block *ipb)
10{
11	int i;
12	size_t len;
13	char has_lowercase = 0;
14
15	len = 0;
16	if ((ipb->ccw.vm_flags & IPL_PB0_CCW_VM_FLAG_VP) &&
17	    (ipb->ccw.vm_parm_len > 0)) {
18
19		len = min_t(size_t, size - 1, ipb->ccw.vm_parm_len);
20		memcpy(dest, ipb->ccw.vm_parm, len);
21		/* If at least one character is lowercase, we assume mixed
22		 * case; otherwise we convert everything to lowercase.
23		 */
24		for (i = 0; i < len; i++)
25			if ((dest[i] > 0x80 && dest[i] < 0x8a) || /* a-i */
26			    (dest[i] > 0x90 && dest[i] < 0x9a) || /* j-r */
27			    (dest[i] > 0xa1 && dest[i] < 0xaa)) { /* s-z */
28				has_lowercase = 1;
29				break;
30			}
31		if (!has_lowercase)
32			EBC_TOLOWER(dest, len);
33		EBCASC(dest, len);
34	}
35	dest[len] = 0;
36
37	return len;
38}
39