174 lines
4.0 KiB
C
174 lines
4.0 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* OS info memory interface
|
|
*
|
|
* Copyright IBM Corp. 2012
|
|
* Author(s): Michael Holzheu <holzheu@linux.vnet.ibm.com>
|
|
*/
|
|
|
|
#define KMSG_COMPONENT "os_info"
|
|
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
|
|
|
|
#include <linux/crash_dump.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/slab.h>
|
|
#include <asm/checksum.h>
|
|
#include <asm/abs_lowcore.h>
|
|
#include <asm/os_info.h>
|
|
#include <asm/maccess.h>
|
|
#include <asm/asm-offsets.h>
|
|
|
|
/*
|
|
* OS info structure has to be page aligned
|
|
*/
|
|
static struct os_info os_info __page_aligned_data;
|
|
|
|
/*
|
|
* Compute checksum over OS info structure
|
|
*/
|
|
u32 os_info_csum(struct os_info *os_info)
|
|
{
|
|
int size = sizeof(*os_info) - offsetof(struct os_info, version_major);
|
|
return (__force u32)csum_partial(&os_info->version_major, size, 0);
|
|
}
|
|
|
|
/*
|
|
* Add crashkernel info to OS info and update checksum
|
|
*/
|
|
void os_info_crashkernel_add(unsigned long base, unsigned long size)
|
|
{
|
|
os_info.crashkernel_addr = (u64)(unsigned long)base;
|
|
os_info.crashkernel_size = (u64)(unsigned long)size;
|
|
os_info.csum = os_info_csum(&os_info);
|
|
}
|
|
|
|
/*
|
|
* Add OS info entry and update checksum
|
|
*/
|
|
void os_info_entry_add(int nr, void *ptr, u64 size)
|
|
{
|
|
os_info.entry[nr].addr = __pa(ptr);
|
|
os_info.entry[nr].size = size;
|
|
os_info.entry[nr].csum = (__force u32)csum_partial(ptr, size, 0);
|
|
os_info.csum = os_info_csum(&os_info);
|
|
}
|
|
|
|
/*
|
|
* Initialize OS info structure and set lowcore pointer
|
|
*/
|
|
void __init os_info_init(void)
|
|
{
|
|
struct lowcore *abs_lc;
|
|
|
|
os_info.version_major = OS_INFO_VERSION_MAJOR;
|
|
os_info.version_minor = OS_INFO_VERSION_MINOR;
|
|
os_info.magic = OS_INFO_MAGIC;
|
|
os_info.csum = os_info_csum(&os_info);
|
|
abs_lc = get_abs_lowcore();
|
|
abs_lc->os_info = __pa(&os_info);
|
|
put_abs_lowcore(abs_lc);
|
|
}
|
|
|
|
#ifdef CONFIG_CRASH_DUMP
|
|
|
|
static struct os_info *os_info_old;
|
|
|
|
/*
|
|
* Allocate and copy OS info entry from oldmem
|
|
*/
|
|
static void os_info_old_alloc(int nr, int align)
|
|
{
|
|
unsigned long addr, size = 0;
|
|
char *buf, *buf_align, *msg;
|
|
u32 csum;
|
|
|
|
addr = os_info_old->entry[nr].addr;
|
|
if (!addr) {
|
|
msg = "not available";
|
|
goto fail;
|
|
}
|
|
size = os_info_old->entry[nr].size;
|
|
buf = kmalloc(size + align - 1, GFP_KERNEL);
|
|
if (!buf) {
|
|
msg = "alloc failed";
|
|
goto fail;
|
|
}
|
|
buf_align = PTR_ALIGN(buf, align);
|
|
if (copy_oldmem_kernel(buf_align, addr, size)) {
|
|
msg = "copy failed";
|
|
goto fail_free;
|
|
}
|
|
csum = (__force u32)csum_partial(buf_align, size, 0);
|
|
if (csum != os_info_old->entry[nr].csum) {
|
|
msg = "checksum failed";
|
|
goto fail_free;
|
|
}
|
|
os_info_old->entry[nr].addr = (u64)(unsigned long)buf_align;
|
|
msg = "copied";
|
|
goto out;
|
|
fail_free:
|
|
kfree(buf);
|
|
fail:
|
|
os_info_old->entry[nr].addr = 0;
|
|
out:
|
|
pr_info("entry %i: %s (addr=0x%lx size=%lu)\n",
|
|
nr, msg, addr, size);
|
|
}
|
|
|
|
/*
|
|
* Initialize os info and os info entries from oldmem
|
|
*/
|
|
static void os_info_old_init(void)
|
|
{
|
|
static int os_info_init;
|
|
unsigned long addr;
|
|
|
|
if (os_info_init)
|
|
return;
|
|
if (!oldmem_data.start)
|
|
goto fail;
|
|
if (copy_oldmem_kernel(&addr, __LC_OS_INFO, sizeof(addr)))
|
|
goto fail;
|
|
if (addr == 0 || addr % PAGE_SIZE)
|
|
goto fail;
|
|
os_info_old = kzalloc(sizeof(*os_info_old), GFP_KERNEL);
|
|
if (!os_info_old)
|
|
goto fail;
|
|
if (copy_oldmem_kernel(os_info_old, addr, sizeof(*os_info_old)))
|
|
goto fail_free;
|
|
if (os_info_old->magic != OS_INFO_MAGIC)
|
|
goto fail_free;
|
|
if (os_info_old->csum != os_info_csum(os_info_old))
|
|
goto fail_free;
|
|
if (os_info_old->version_major > OS_INFO_VERSION_MAJOR)
|
|
goto fail_free;
|
|
os_info_old_alloc(OS_INFO_VMCOREINFO, 1);
|
|
os_info_old_alloc(OS_INFO_REIPL_BLOCK, 1);
|
|
pr_info("crashkernel: addr=0x%lx size=%lu\n",
|
|
(unsigned long) os_info_old->crashkernel_addr,
|
|
(unsigned long) os_info_old->crashkernel_size);
|
|
os_info_init = 1;
|
|
return;
|
|
fail_free:
|
|
kfree(os_info_old);
|
|
fail:
|
|
os_info_init = 1;
|
|
os_info_old = NULL;
|
|
}
|
|
|
|
/*
|
|
* Return pointer to os infor entry and its size
|
|
*/
|
|
void *os_info_old_entry(int nr, unsigned long *size)
|
|
{
|
|
os_info_old_init();
|
|
|
|
if (!os_info_old)
|
|
return NULL;
|
|
if (!os_info_old->entry[nr].addr)
|
|
return NULL;
|
|
*size = (unsigned long) os_info_old->entry[nr].size;
|
|
return (void *)(unsigned long)os_info_old->entry[nr].addr;
|
|
}
|
|
#endif
|