diff options
Diffstat (limited to 'arch/s390/kernel/cpcmd.c')
| -rw-r--r-- | arch/s390/kernel/cpcmd.c | 153 |
1 files changed, 72 insertions, 81 deletions
diff --git a/arch/s390/kernel/cpcmd.c b/arch/s390/kernel/cpcmd.c index d47fecb42cc..d7b0c4d2788 100644 --- a/arch/s390/kernel/cpcmd.c +++ b/arch/s390/kernel/cpcmd.c @@ -1,12 +1,13 @@ /* - * arch/s390/kernel/cpcmd.c - * * S390 version - * Copyright (C) 1999,2005 IBM Deutschland Entwicklung GmbH, IBM Corporation + * 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> @@ -15,118 +16,108 @@ #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]; +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( +#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 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( +#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"); + *rlen = reg5; + return reg4; +} + /* - * the caller of __cpcmd has to ensure that the response buffer is below 2 GB + * __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) { - const int mask = 0x40000000L; - unsigned long flags; - int return_code; - int return_len; int cmdlen; + int rc; + int response_len; - spin_lock_irqsave(&cpcmd_lock, flags); cmdlen = strlen(cmd); BUG_ON(cmdlen > 240); memcpy(cpcmd_buf, cmd, cmdlen); ASCEBC(cpcmd_buf, cmdlen); - if (response != NULL && rlen > 0) { + if (response) { memset(response, 0, rlen); -#ifndef CONFIG_ARCH_S390X - asm volatile ( "lra 2,0(%2)\n" - "lr 4,%3\n" - "o 4,%6\n" - "lra 3,0(%4)\n" - "lr 5,%5\n" - "diag 2,4,0x8\n" - "brc 8, 1f\n" - "ar 5, %5\n" - "1: \n" - "lr %0,4\n" - "lr %1,5\n" - : "=d" (return_code), "=d" (return_len) - : "a" (cpcmd_buf), "d" (cmdlen), - "a" (response), "d" (rlen), "m" (mask) - : "cc", "2", "3", "4", "5" ); -#else /* CONFIG_ARCH_S390X */ - asm volatile ( "lrag 2,0(%2)\n" - "lgr 4,%3\n" - "o 4,%6\n" - "lrag 3,0(%4)\n" - "lgr 5,%5\n" - "sam31\n" - "diag 2,4,0x8\n" - "sam64\n" - "brc 8, 1f\n" - "agr 5, %5\n" - "1: \n" - "lgr %0,4\n" - "lgr %1,5\n" - : "=d" (return_code), "=d" (return_len) - : "a" (cpcmd_buf), "d" (cmdlen), - "a" (response), "d" (rlen), "m" (mask) - : "cc", "2", "3", "4", "5" ); -#endif /* CONFIG_ARCH_S390X */ - EBCASC(response, rlen); + response_len = rlen; + rc = diag8_response(cmdlen, response, &rlen); + EBCASC(response, response_len); } else { - return_len = 0; -#ifndef CONFIG_ARCH_S390X - asm volatile ( "lra 2,0(%1)\n" - "lr 3,%2\n" - "diag 2,3,0x8\n" - "lr %0,3\n" - : "=d" (return_code) - : "a" (cpcmd_buf), "d" (cmdlen) - : "2", "3" ); -#else /* CONFIG_ARCH_S390X */ - asm volatile ( "lrag 2,0(%1)\n" - "lgr 3,%2\n" - "sam31\n" - "diag 2,3,0x8\n" - "sam64\n" - "lgr %0,3\n" - : "=d" (return_code) - : "a" (cpcmd_buf), "d" (cmdlen) - : "2", "3" ); -#endif /* CONFIG_ARCH_S390X */ + rc = diag8_noresponse(cmdlen); } - spin_unlock_irqrestore(&cpcmd_lock, flags); - if (response_code != NULL) - *response_code = return_code; - return return_len; + if (response_code) + *response_code = rc; + return rlen; } - EXPORT_SYMBOL(__cpcmd); -#ifdef CONFIG_ARCH_S390X int cpcmd(const char *cmd, char *response, int rlen, int *response_code) { char *lowbuf; int len; + unsigned long flags; - if ((rlen == 0) || (response == NULL) - || !((unsigned long)response >> 31)) - len = __cpcmd(cmd, response, rlen, response_code); - else { + 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"); + 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); -#endif /* CONFIG_ARCH_S390X */ |