linux-stable/arch/s390/kernel/ipl_vmparm.c
Martin Schwidefsky 5f1207fbe7 s390/ipl: provide uapi header for list directed IPL
The IPL parameter block is used as an interface between Linux and
the machine to query and change the boot device and boot options.
To be able to create IPL parameter block in user space and pass it
as segment to kexec provide an uapi header with proper structure
definitions for the block.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-04-26 12:34:05 +02:00

36 lines
916 B
C

// SPDX-License-Identifier: GPL-2.0
#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;
}