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