mirror of https://gitee.com/openkylin/linux.git
116 lines
2.8 KiB
C
116 lines
2.8 KiB
C
/*
|
|
* 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/module.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/spinlock.h>
|
|
#include <linux/stddef.h>
|
|
#include <linux/string.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)
|
|
{
|
|
register unsigned long reg2 asm ("2") = (addr_t) cpcmd_buf;
|
|
register unsigned long reg3 asm ("3") = cmdlen;
|
|
|
|
asm volatile(
|
|
" sam31\n"
|
|
" diag %1,%0,0x8\n"
|
|
" sam64\n"
|
|
: "+d" (reg3) : "d" (reg2) : "cc");
|
|
return reg3;
|
|
}
|
|
|
|
static int diag8_response(int cmdlen, char *response, int *rlen)
|
|
{
|
|
register unsigned long reg2 asm ("2") = (addr_t) cpcmd_buf;
|
|
register unsigned long reg3 asm ("3") = (addr_t) response;
|
|
register unsigned long reg4 asm ("4") = cmdlen | 0x40000000L;
|
|
register unsigned long reg5 asm ("5") = *rlen;
|
|
|
|
asm volatile(
|
|
" sam31\n"
|
|
" diag %2,%0,0x8\n"
|
|
" sam64\n"
|
|
" brc 8,1f\n"
|
|
" agr %1,%4\n"
|
|
"1:\n"
|
|
: "+d" (reg4), "+d" (reg5)
|
|
: "d" (reg2), "d" (reg3), "d" (*rlen) : "cc");
|
|
*rlen = reg5;
|
|
return reg4;
|
|
}
|
|
|
|
/*
|
|
* __cpcmd has some restrictions over cpcmd
|
|
* - the response buffer must reside below 2GB (if any)
|
|
* - __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)
|
|
{
|
|
char *lowbuf;
|
|
int len;
|
|
unsigned long flags;
|
|
|
|
if ((virt_to_phys(response) != (unsigned long) response) ||
|
|
(((unsigned long)response + rlen) >> 31)) {
|
|
lowbuf = kmalloc(rlen, GFP_KERNEL | GFP_DMA);
|
|
if (!lowbuf) {
|
|
pr_warning("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);
|