cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

physaddr.c (2320B)

      1// SPDX-License-Identifier: GPL-2.0
      2#include <linux/memblock.h>
      3#include <linux/mmdebug.h>
      4#include <linux/export.h>
      5#include <linux/mm.h>
      6
      7#include <asm/page.h>
      8#include <linux/vmalloc.h>
      9
     10#include "physaddr.h"
     11
     12#ifdef CONFIG_X86_64
     13
     14#ifdef CONFIG_DEBUG_VIRTUAL
     15unsigned long __phys_addr(unsigned long x)
     16{
     17	unsigned long y = x - __START_KERNEL_map;
     18
     19	/* use the carry flag to determine if x was < __START_KERNEL_map */
     20	if (unlikely(x > y)) {
     21		x = y + phys_base;
     22
     23		VIRTUAL_BUG_ON(y >= KERNEL_IMAGE_SIZE);
     24	} else {
     25		x = y + (__START_KERNEL_map - PAGE_OFFSET);
     26
     27		/* carry flag will be set if starting x was >= PAGE_OFFSET */
     28		VIRTUAL_BUG_ON((x > y) || !phys_addr_valid(x));
     29	}
     30
     31	return x;
     32}
     33EXPORT_SYMBOL(__phys_addr);
     34
     35unsigned long __phys_addr_symbol(unsigned long x)
     36{
     37	unsigned long y = x - __START_KERNEL_map;
     38
     39	/* only check upper bounds since lower bounds will trigger carry */
     40	VIRTUAL_BUG_ON(y >= KERNEL_IMAGE_SIZE);
     41
     42	return y + phys_base;
     43}
     44EXPORT_SYMBOL(__phys_addr_symbol);
     45#endif
     46
     47bool __virt_addr_valid(unsigned long x)
     48{
     49	unsigned long y = x - __START_KERNEL_map;
     50
     51	/* use the carry flag to determine if x was < __START_KERNEL_map */
     52	if (unlikely(x > y)) {
     53		x = y + phys_base;
     54
     55		if (y >= KERNEL_IMAGE_SIZE)
     56			return false;
     57	} else {
     58		x = y + (__START_KERNEL_map - PAGE_OFFSET);
     59
     60		/* carry flag will be set if starting x was >= PAGE_OFFSET */
     61		if ((x > y) || !phys_addr_valid(x))
     62			return false;
     63	}
     64
     65	return pfn_valid(x >> PAGE_SHIFT);
     66}
     67EXPORT_SYMBOL(__virt_addr_valid);
     68
     69#else
     70
     71#ifdef CONFIG_DEBUG_VIRTUAL
     72unsigned long __phys_addr(unsigned long x)
     73{
     74	unsigned long phys_addr = x - PAGE_OFFSET;
     75	/* VMALLOC_* aren't constants  */
     76	VIRTUAL_BUG_ON(x < PAGE_OFFSET);
     77	VIRTUAL_BUG_ON(__vmalloc_start_set && is_vmalloc_addr((void *) x));
     78	/* max_low_pfn is set early, but not _that_ early */
     79	if (max_low_pfn) {
     80		VIRTUAL_BUG_ON((phys_addr >> PAGE_SHIFT) > max_low_pfn);
     81		BUG_ON(slow_virt_to_phys((void *)x) != phys_addr);
     82	}
     83	return phys_addr;
     84}
     85EXPORT_SYMBOL(__phys_addr);
     86#endif
     87
     88bool __virt_addr_valid(unsigned long x)
     89{
     90	if (x < PAGE_OFFSET)
     91		return false;
     92	if (__vmalloc_start_set && is_vmalloc_addr((void *) x))
     93		return false;
     94	if (x >= FIXADDR_START)
     95		return false;
     96	return pfn_valid((x - PAGE_OFFSET) >> PAGE_SHIFT);
     97}
     98EXPORT_SYMBOL(__virt_addr_valid);
     99
    100#endif	/* CONFIG_X86_64 */