blob: 32d710f7eb84ce0b67d46be35be38bf8d02c78fe [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* Memory preserving reboot related code.
*
* Created by: Hariprasad Nellitheertha (hari@in.ibm.com)
* Copyright (C) IBM Corporation, 2004. All rights reserved
*/
#include <linux/errno.h>
#include <linux/crash_dump.h>
#include <linux/uio.h>
#include <linux/io.h>
#include <linux/cc_platform.h>
static ssize_t __copy_oldmem_page(struct iov_iter *iter, unsigned long pfn,
size_t csize, unsigned long offset,
bool encrypted)
{
void *vaddr;
if (!csize)
return 0;
if (encrypted)
vaddr = (__force void *)ioremap_encrypted(pfn << PAGE_SHIFT, PAGE_SIZE);
else
vaddr = (__force void *)ioremap_cache(pfn << PAGE_SHIFT, PAGE_SIZE);
if (!vaddr)
return -ENOMEM;
csize = copy_to_iter(vaddr + offset, csize, iter);
iounmap((void __iomem *)vaddr);
return csize;
}
ssize_t copy_oldmem_page(struct iov_iter *iter, unsigned long pfn, size_t csize,
unsigned long offset)
{
return __copy_oldmem_page(iter, pfn, csize, offset, false);
}
/*
* copy_oldmem_page_encrypted - same as copy_oldmem_page() above but ioremap the
* memory with the encryption mask set to accommodate kdump on SME-enabled
* machines.
*/
ssize_t copy_oldmem_page_encrypted(struct iov_iter *iter, unsigned long pfn,
size_t csize, unsigned long offset)
{
return __copy_oldmem_page(iter, pfn, csize, offset, true);
}
ssize_t elfcorehdr_read(char *buf, size_t count, u64 *ppos)
{
struct kvec kvec = { .iov_base = buf, .iov_len = count };
struct iov_iter iter;
iov_iter_kvec(&iter, ITER_DEST, &kvec, 1, count);
return read_from_oldmem(&iter, count, ppos,
cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT));
}