xref: /linux/arch/arm/mm/physaddr.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/bug.h>
3 #include <linux/export.h>
4 #include <linux/types.h>
5 #include <linux/mmdebug.h>
6 #include <linux/mm.h>
7 
8 #include <asm/sections.h>
9 #include <asm/page.h>
10 #include <asm/fixmap.h>
11 #include <asm/dma.h>
12 
13 #include "mm.h"
14 
15 static inline bool __virt_addr_valid(unsigned long x)
16 {
17 	/*
18 	 * high_memory does not get immediately defined, and there
19 	 * are early callers of __pa() against PAGE_OFFSET
20 	 */
21 	if (!high_memory && x >= PAGE_OFFSET)
22 		return true;
23 
24 	if (high_memory && x >= PAGE_OFFSET && x < (unsigned long)high_memory)
25 		return true;
26 
27 	/*
28 	 * MAX_DMA_ADDRESS is a virtual address that may not correspond to an
29 	 * actual physical address. Enough code relies on __pa(MAX_DMA_ADDRESS)
30 	 * that we just need to work around it and always return true.
31 	 */
32 	if (x == MAX_DMA_ADDRESS)
33 		return true;
34 
35 	return false;
36 }
37 
38 phys_addr_t __virt_to_phys(unsigned long x)
39 {
40 	WARN(!__virt_addr_valid(x),
41 	     "virt_to_phys used for non-linear address: %pK (%pS)\n",
42 	     (void *)x, (void *)x);
43 
44 	return __virt_to_phys_nodebug(x);
45 }
46 EXPORT_SYMBOL(__virt_to_phys);
47 
48 phys_addr_t __phys_addr_symbol(unsigned long x)
49 {
50 	/* This is bounds checking against the kernel image only.
51 	 * __pa_symbol should only be used on kernel symbol addresses.
52 	 */
53 	VIRTUAL_BUG_ON(x < (unsigned long)KERNEL_START ||
54 		       x > (unsigned long)KERNEL_END);
55 
56 	return __pa_symbol_nodebug(x);
57 }
58 EXPORT_SYMBOL(__phys_addr_symbol);
59