1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
|
/*
* Based on arch/arm/mm/ioremap.c
*
* (C) Copyright 1995 1996 Linus Torvalds
* Hacked for ARM by Phil Blundell <philb@gnu.org>
* Hacked to allow all architectures to build, and various cleanups
* by Russell King
* Copyright (C) 2012 ARM Ltd.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/export.h>
#include <linux/mm.h>
#include <linux/vmalloc.h>
#include <linux/io.h>
static void __iomem *__ioremap_caller(phys_addr_t phys_addr, size_t size,
pgprot_t prot, void *caller)
{
unsigned long last_addr;
unsigned long offset = phys_addr & ~PAGE_MASK;
int err;
unsigned long addr;
struct vm_struct *area;
/*
* Page align the mapping address and size, taking account of any
* offset.
*/
phys_addr &= PAGE_MASK;
size = PAGE_ALIGN(size + offset);
/*
* Don't allow wraparound, zero size or outside PHYS_MASK.
*/
last_addr = phys_addr + size - 1;
if (!size || last_addr < phys_addr || (last_addr & ~PHYS_MASK))
return NULL;
/*
* Don't allow RAM to be mapped.
*/
if (WARN_ON(pfn_valid(__phys_to_pfn(phys_addr))))
return NULL;
area = get_vm_area_caller(size, VM_IOREMAP, caller);
if (!area)
return NULL;
addr = (unsigned long)area->addr;
err = ioremap_page_range(addr, addr + size, phys_addr, prot);
if (err) {
vunmap((void *)addr);
return NULL;
}
return (void __iomem *)(offset + addr);
}
void __iomem *__ioremap(phys_addr_t phys_addr, size_t size, pgprot_t prot)
{
return __ioremap_caller(phys_addr, size, prot,
__builtin_return_address(0));
}
EXPORT_SYMBOL(__ioremap);
void __iounmap(volatile void __iomem *io_addr)
{
void *addr = (void *)(PAGE_MASK & (unsigned long)io_addr);
vunmap(addr);
}
EXPORT_SYMBOL(__iounmap);
|
