| /* |
| * arch/s390/kernel/cpcmd.c |
| * |
| * S390 version |
| * Copyright (C) 1999,2005 IBM Deutschland Entwicklung GmbH, IBM Corporation |
| * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com), |
| * Christian Borntraeger (cborntra@de.ibm.com), |
| */ |
| |
| #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/ebcdic.h> |
| #include <asm/cpcmd.h> |
| #include <asm/system.h> |
| #include <asm/io.h> |
| |
| static DEFINE_SPINLOCK(cpcmd_lock); |
| static char cpcmd_buf[241]; |
| |
| /* |
| * __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) |
| { |
| unsigned cmdlen; |
| int return_code, return_len; |
| |
| cmdlen = strlen(cmd); |
| BUG_ON(cmdlen > 240); |
| memcpy(cpcmd_buf, cmd, cmdlen); |
| ASCEBC(cpcmd_buf, cmdlen); |
| |
| if (response != NULL && rlen > 0) { |
| 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; |
| |
| memset(response, 0, rlen); |
| asm volatile( |
| #ifndef CONFIG_64BIT |
| " diag %2,%0,0x8\n" |
| " brc 8,1f\n" |
| " ar %1,%4\n" |
| #else /* CONFIG_64BIT */ |
| " sam31\n" |
| " diag %2,%0,0x8\n" |
| " sam64\n" |
| " brc 8,1f\n" |
| " agr %1,%4\n" |
| #endif /* CONFIG_64BIT */ |
| "1:\n" |
| : "+d" (reg4), "+d" (reg5) |
| : "d" (reg2), "d" (reg3), "d" (rlen) : "cc"); |
| return_code = (int) reg4; |
| return_len = (int) reg5; |
| EBCASC(response, rlen); |
| } else { |
| register unsigned long reg2 asm ("2") = (addr_t) cpcmd_buf; |
| register unsigned long reg3 asm ("3") = cmdlen; |
| return_len = 0; |
| asm volatile( |
| #ifndef CONFIG_64BIT |
| " diag %1,%0,0x8\n" |
| #else /* CONFIG_64BIT */ |
| " sam31\n" |
| " diag %1,%0,0x8\n" |
| " sam64\n" |
| #endif /* CONFIG_64BIT */ |
| : "+d" (reg3) : "d" (reg2) : "cc"); |
| return_code = (int) reg3; |
| } |
| if (response_code != NULL) |
| *response_code = return_code; |
| return return_len; |
| } |
| |
| 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) { |
| printk(KERN_WARNING |
| "cpcmd: could not allocate 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); |