mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-24 01:41:39 +00:00
![Alexander Gordeev](/assets/img/avatar_default.png)
Virtual Console Function DIAGNOSE 8 accepts physical addresses of command and response strings. Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
114 lines
2.5 KiB
C
114 lines
2.5 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* S390 version
|
|
* Copyright IBM Corp. 1999, 2007
|
|
* Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
|
|
* Christian Borntraeger (cborntra@de.ibm.com),
|
|
*/
|
|
|
|
#define KMSG_COMPONENT "cpcmd"
|
|
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/export.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/spinlock.h>
|
|
#include <linux/stddef.h>
|
|
#include <linux/string.h>
|
|
#include <linux/mm.h>
|
|
#include <asm/diag.h>
|
|
#include <asm/ebcdic.h>
|
|
#include <asm/cpcmd.h>
|
|
#include <asm/io.h>
|
|
|
|
static DEFINE_SPINLOCK(cpcmd_lock);
|
|
static char cpcmd_buf[241];
|
|
|
|
static int diag8_noresponse(int cmdlen)
|
|
{
|
|
asm volatile(
|
|
" diag %[rx],%[ry],0x8\n"
|
|
: [ry] "+&d" (cmdlen)
|
|
: [rx] "d" (__pa(cpcmd_buf))
|
|
: "cc");
|
|
return cmdlen;
|
|
}
|
|
|
|
static int diag8_response(int cmdlen, char *response, int *rlen)
|
|
{
|
|
union register_pair rx, ry;
|
|
int cc;
|
|
|
|
rx.even = __pa(cpcmd_buf);
|
|
rx.odd = __pa(response);
|
|
ry.even = cmdlen | 0x40000000L;
|
|
ry.odd = *rlen;
|
|
asm volatile(
|
|
" diag %[rx],%[ry],0x8\n"
|
|
" ipm %[cc]\n"
|
|
" srl %[cc],28\n"
|
|
: [cc] "=&d" (cc), [ry] "+&d" (ry.pair)
|
|
: [rx] "d" (rx.pair)
|
|
: "cc");
|
|
if (cc)
|
|
*rlen += ry.odd;
|
|
else
|
|
*rlen = ry.odd;
|
|
return ry.even;
|
|
}
|
|
|
|
/*
|
|
* __cpcmd has some restrictions over cpcmd
|
|
* - __cpcmd is unlocked and therefore not SMP-safe
|
|
*/
|
|
int __cpcmd(const char *cmd, char *response, int rlen, int *response_code)
|
|
{
|
|
int cmdlen;
|
|
int rc;
|
|
int response_len;
|
|
|
|
cmdlen = strlen(cmd);
|
|
BUG_ON(cmdlen > 240);
|
|
memcpy(cpcmd_buf, cmd, cmdlen);
|
|
ASCEBC(cpcmd_buf, cmdlen);
|
|
|
|
diag_stat_inc(DIAG_STAT_X008);
|
|
if (response) {
|
|
memset(response, 0, rlen);
|
|
response_len = rlen;
|
|
rc = diag8_response(cmdlen, response, &rlen);
|
|
EBCASC(response, response_len);
|
|
} else {
|
|
rc = diag8_noresponse(cmdlen);
|
|
}
|
|
if (response_code)
|
|
*response_code = rc;
|
|
return rlen;
|
|
}
|
|
EXPORT_SYMBOL(__cpcmd);
|
|
|
|
int cpcmd(const char *cmd, char *response, int rlen, int *response_code)
|
|
{
|
|
unsigned long flags;
|
|
char *lowbuf;
|
|
int len;
|
|
|
|
if (is_vmalloc_or_module_addr(response)) {
|
|
lowbuf = kmalloc(rlen, GFP_KERNEL);
|
|
if (!lowbuf) {
|
|
pr_warn("The cpcmd kernel function failed to allocate a response buffer\n");
|
|
return -ENOMEM;
|
|
}
|
|
spin_lock_irqsave(&cpcmd_lock, flags);
|
|
len = __cpcmd(cmd, lowbuf, rlen, response_code);
|
|
spin_unlock_irqrestore(&cpcmd_lock, flags);
|
|
memcpy(response, lowbuf, rlen);
|
|
kfree(lowbuf);
|
|
} else {
|
|
spin_lock_irqsave(&cpcmd_lock, flags);
|
|
len = __cpcmd(cmd, response, rlen, response_code);
|
|
spin_unlock_irqrestore(&cpcmd_lock, flags);
|
|
}
|
|
return len;
|
|
}
|
|
EXPORT_SYMBOL(cpcmd);
|