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// SPDX-License-Identifier: GPL-2.0
/*
* Re-map IO memory to kernel address space so that we can access it.
* This is needed for high PCI addresses that aren't mapped in the
* 640k-1MB IO memory area on PC's
*
* (C) Copyright 1995 1996 Linus Torvalds
*/
#include <linux/vmalloc.h>
#include <linux/mm.h>
#include <linux/io.h>
#include <linux/export.h>
void __iomem *ioremap_prot(phys_addr_t phys_addr, size_t size,
unsigned long prot)
{
unsigned long offset, vaddr;
phys_addr_t last_addr;
struct vm_struct *area;
/* Disallow wrap-around or zero size */
last_addr = phys_addr + size - 1;
if (!size || last_addr < phys_addr)
return NULL;
/* Page-align mappings */
offset = phys_addr & (~PAGE_MASK);
phys_addr -= offset;
size = PAGE_ALIGN(size + offset);
if (!ioremap_allowed(phys_addr, size, prot))
return NULL;
area = get_vm_area_caller(size, VM_IOREMAP,
__builtin_return_address(0));
if (!area)
return NULL;
vaddr = (unsigned long)area->addr;
area->phys_addr = phys_addr;
if (ioremap_page_range(vaddr, vaddr + size, phys_addr,
__pgprot(prot))) {
free_vm_area(area);
return NULL;
}
return (void __iomem *)(vaddr + offset);
}
EXPORT_SYMBOL(ioremap_prot);
void iounmap(volatile void __iomem *addr)
{
void *vaddr = (void *)((unsigned long)addr & PAGE_MASK);
if (!iounmap_allowed(vaddr))
return;
if (is_vmalloc_addr(vaddr))
vunmap(vaddr);
}
EXPORT_SYMBOL(iounmap);
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