kernel-ark/arch/ia64/sn/kernel/mca.c
Keith Owens 32709d8ae6 [IA64] SAL to OS callbacks cannot call sleeping
When SAL calls back into the OS, the OS code is running with preempt
disabled so it cannot call sleeping functions.

Signed-off-by: Keith Owens <kaos@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2005-05-03 13:48:55 -07:00

144 lines
4.0 KiB
C

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (c) 2000-2004 Silicon Graphics, Inc. All Rights Reserved.
*/
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/timer.h>
#include <linux/vmalloc.h>
#include <asm/mca.h>
#include <asm/sal.h>
#include <asm/sn/sn_sal.h>
/*
* Interval for calling SAL to poll for errors that do NOT cause error
* interrupts. SAL will raise a CPEI if any errors are present that
* need to be logged.
*/
#define CPEI_INTERVAL (5*HZ)
struct timer_list sn_cpei_timer;
void sn_init_cpei_timer(void);
/* Printing oemdata from mca uses data that is not passed through SAL, it is
* global. Only one user at a time.
*/
static DECLARE_MUTEX(sn_oemdata_mutex);
static u8 **sn_oemdata;
static u64 *sn_oemdata_size, sn_oemdata_bufsize;
/*
* print_hook
*
* This function is the callback routine that SAL calls to log error
* info for platform errors. buf is appended to sn_oemdata, resizing as
* required.
* Note: this is a SAL to OS callback, running under the same rules as the SAL
* code. SAL calls are run with preempt disabled so this routine must not
* sleep. vmalloc can sleep so print_hook cannot resize the output buffer
* itself, instead it must set the required size and return to let the caller
* resize the buffer then redrive the SAL call.
*/
static int print_hook(const char *fmt, ...)
{
char buf[400];
int len;
va_list args;
va_start(args, fmt);
vsnprintf(buf, sizeof(buf), fmt, args);
va_end(args);
len = strlen(buf);
if (*sn_oemdata_size + len <= sn_oemdata_bufsize)
memcpy(*sn_oemdata + *sn_oemdata_size, buf, len);
*sn_oemdata_size += len;
return 0;
}
static void sn_cpei_handler(int irq, void *devid, struct pt_regs *regs)
{
/*
* this function's sole purpose is to call SAL when we receive
* a CE interrupt from SHUB or when the timer routine decides
* we need to call SAL to check for CEs.
*/
/* CALL SAL_LOG_CE */
ia64_sn_plat_cpei_handler();
}
static void sn_cpei_timer_handler(unsigned long dummy)
{
sn_cpei_handler(-1, NULL, NULL);
mod_timer(&sn_cpei_timer, jiffies + CPEI_INTERVAL);
}
void sn_init_cpei_timer(void)
{
init_timer(&sn_cpei_timer);
sn_cpei_timer.expires = jiffies + CPEI_INTERVAL;
sn_cpei_timer.function = sn_cpei_timer_handler;
add_timer(&sn_cpei_timer);
}
static int
sn_platform_plat_specific_err_print(const u8 * sect_header, u8 ** oemdata,
u64 * oemdata_size)
{
down(&sn_oemdata_mutex);
sn_oemdata = oemdata;
sn_oemdata_size = oemdata_size;
sn_oemdata_bufsize = 0;
*sn_oemdata_size = PAGE_SIZE; /* first guess at how much data will be generated */
while (*sn_oemdata_size > sn_oemdata_bufsize) {
u8 *newbuf = vmalloc(*sn_oemdata_size);
if (!newbuf) {
printk(KERN_ERR "%s: unable to extend sn_oemdata\n",
__FUNCTION__);
return 1;
}
vfree(*sn_oemdata);
*sn_oemdata = newbuf;
sn_oemdata_bufsize = *sn_oemdata_size;
*sn_oemdata_size = 0;
ia64_sn_plat_specific_err_print(print_hook, (char *)sect_header);
}
up(&sn_oemdata_mutex);
return 0;
}
/* Callback when userspace salinfo wants to decode oem data via the platform
* kernel and/or prom.
*/
int sn_salinfo_platform_oemdata(const u8 *sect_header, u8 **oemdata, u64 *oemdata_size)
{
efi_guid_t guid = *(efi_guid_t *)sect_header;
int valid = 0;
*oemdata_size = 0;
vfree(*oemdata);
*oemdata = NULL;
if (efi_guidcmp(guid, SAL_PLAT_SPECIFIC_ERR_SECT_GUID) == 0) {
sal_log_plat_specific_err_info_t *psei = (sal_log_plat_specific_err_info_t *)sect_header;
valid = psei->valid.oem_data;
} else if (efi_guidcmp(guid, SAL_PLAT_MEM_DEV_ERR_SECT_GUID) == 0) {
sal_log_mem_dev_err_info_t *mdei = (sal_log_mem_dev_err_info_t *)sect_header;
valid = mdei->valid.oem_data;
}
if (valid)
return sn_platform_plat_specific_err_print(sect_header, oemdata, oemdata_size);
else
return 0;
}
static int __init sn_salinfo_init(void)
{
salinfo_platform_oemdata = &sn_salinfo_platform_oemdata;
return 0;
}
module_init(sn_salinfo_init)