linux/arch/x86/mm/physaddr.c

// SPDX-License-Identifier: GPL-2.0
#include <linux/memblock.h>
#include <linux/mmdebug.h>
#include <linux/export.h>
#include <linux/mm.h>

#include <asm/page.h>
#include <linux/vmalloc.h>

#include "physaddr.h"

#ifdef CONFIG_X86_64

#ifdef CONFIG_DEBUG_VIRTUAL
unsigned long __phys_addr(unsigned long x)
{ … }
EXPORT_SYMBOL(…);

unsigned long __phys_addr_symbol(unsigned long x)
{ … }
EXPORT_SYMBOL(…);
#endif

bool __virt_addr_valid(unsigned long x)
{ … }
EXPORT_SYMBOL(…);

#else

#ifdef CONFIG_DEBUG_VIRTUAL
unsigned long __phys_addr(unsigned long x)
{
	unsigned long phys_addr = x - PAGE_OFFSET;
	/* VMALLOC_* aren't constants  */
	VIRTUAL_BUG_ON(x < PAGE_OFFSET);
	VIRTUAL_BUG_ON(__vmalloc_start_set && is_vmalloc_addr((void *) x));
	/* max_low_pfn is set early, but not _that_ early */
	if (max_low_pfn) {
		VIRTUAL_BUG_ON((phys_addr >> PAGE_SHIFT) > max_low_pfn);
		BUG_ON(slow_virt_to_phys((void *)x) != phys_addr);
	}
	return phys_addr;
}
EXPORT_SYMBOL(__phys_addr);
#endif

bool __virt_addr_valid(unsigned long x)
{
	if (x < PAGE_OFFSET)
		return false;
	if (__vmalloc_start_set && is_vmalloc_addr((void *) x))
		return false;
	if (x >= FIXADDR_START)
		return false;
	return pfn_valid((x - PAGE_OFFSET) >> PAGE_SHIFT);
}
EXPORT_SYMBOL(__virt_addr_valid);

#endif	/* CONFIG_X86_64 */