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
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
|
#ifndef _X86_64_MADDR_H
#define _X86_64_MADDR_H
#include <xen/features.h>
#include <xen/interface/xen.h>
/**** MACHINE <-> PHYSICAL CONVERSION MACROS ****/
#define INVALID_P2M_ENTRY (~0UL)
#define FOREIGN_FRAME_BIT (1UL<<63)
#define FOREIGN_FRAME(m) ((m) | FOREIGN_FRAME_BIT)
/* Definitions for machine and pseudophysical addresses. */
typedef unsigned long paddr_t;
typedef unsigned long maddr_t;
#ifdef CONFIG_XEN
extern unsigned long *phys_to_machine_mapping;
#undef machine_to_phys_mapping
extern unsigned long *machine_to_phys_mapping;
extern unsigned int machine_to_phys_order;
static inline unsigned long pfn_to_mfn(unsigned long pfn)
{
if (xen_feature(XENFEAT_auto_translated_physmap))
return pfn;
BUG_ON(end_pfn && pfn >= end_pfn);
return phys_to_machine_mapping[pfn] & ~FOREIGN_FRAME_BIT;
}
static inline int phys_to_machine_mapping_valid(unsigned long pfn)
{
if (xen_feature(XENFEAT_auto_translated_physmap))
return 1;
BUG_ON(end_pfn && pfn >= end_pfn);
return (phys_to_machine_mapping[pfn] != INVALID_P2M_ENTRY);
}
static inline unsigned long mfn_to_pfn(unsigned long mfn)
{
unsigned long pfn;
if (xen_feature(XENFEAT_auto_translated_physmap))
return mfn;
if (unlikely((mfn >> machine_to_phys_order) != 0))
return end_pfn;
/* The array access can fail (e.g., device space beyond end of RAM). */
asm (
"1: movq %1,%0\n"
"2:\n"
".section .fixup,\"ax\"\n"
"3: movq %2,%0\n"
" jmp 2b\n"
".previous\n"
".section __ex_table,\"a\"\n"
" .align 8\n"
" .quad 1b,3b\n"
".previous"
: "=r" (pfn)
: "m" (machine_to_phys_mapping[mfn]), "m" (end_pfn) );
return pfn;
}
/*
* We detect special mappings in one of two ways:
* 1. If the MFN is an I/O page then Xen will set the m2p entry
* to be outside our maximum possible pseudophys range.
* 2. If the MFN belongs to a different domain then we will certainly
* not have MFN in our p2m table. Conversely, if the page is ours,
* then we'll have p2m(m2p(MFN))==MFN.
* If we detect a special mapping then it doesn't have a 'struct page'.
* We force !pfn_valid() by returning an out-of-range pointer.
*
* NB. These checks require that, for any MFN that is not in our reservation,
* there is no PFN such that p2m(PFN) == MFN. Otherwise we can get confused if
* we are foreign-mapping the MFN, and the other domain as m2p(MFN) == PFN.
* Yikes! Various places must poke in INVALID_P2M_ENTRY for safety.
*
* NB2. When deliberately mapping foreign pages into the p2m table, you *must*
* use FOREIGN_FRAME(). This will cause pte_pfn() to choke on it, as we
* require. In all the cases we care about, the FOREIGN_FRAME bit is
* masked (e.g., pfn_to_mfn()) so behaviour there is correct.
*/
static inline unsigned long mfn_to_local_pfn(unsigned long mfn)
{
unsigned long pfn = mfn_to_pfn(mfn);
if ((pfn < end_pfn)
&& !xen_feature(XENFEAT_auto_translated_physmap)
&& (phys_to_machine_mapping[pfn] != mfn))
return end_pfn; /* force !pfn_valid() */
return pfn;
}
static inline void set_phys_to_machine(unsigned long pfn, unsigned long mfn)
{
BUG_ON(end_pfn && pfn >= end_pfn);
if (xen_feature(XENFEAT_auto_translated_physmap)) {
BUG_ON(pfn != mfn && mfn != INVALID_P2M_ENTRY);
return;
}
phys_to_machine_mapping[pfn] = mfn;
}
static inline maddr_t phys_to_machine(paddr_t phys)
{
maddr_t machine = pfn_to_mfn(phys >> PAGE_SHIFT);
machine = (machine << PAGE_SHIFT) | (phys & ~PAGE_MASK);
return machine;
}
static inline paddr_t machine_to_phys(maddr_t machine)
{
paddr_t phys = mfn_to_pfn(machine >> PAGE_SHIFT);
phys = (phys << PAGE_SHIFT) | (machine & ~PAGE_MASK);
return phys;
}
static inline paddr_t pte_phys_to_machine(paddr_t phys)
{
maddr_t machine;
machine = pfn_to_mfn((phys & PHYSICAL_PAGE_MASK) >> PAGE_SHIFT);
machine = (machine << PAGE_SHIFT) | (phys & ~PHYSICAL_PAGE_MASK);
return machine;
}
static inline paddr_t pte_machine_to_phys(maddr_t machine)
{
paddr_t phys;
phys = mfn_to_pfn((machine & PHYSICAL_PAGE_MASK) >> PAGE_SHIFT);
phys = (phys << PAGE_SHIFT) | (machine & ~PHYSICAL_PAGE_MASK);
return phys;
}
#else /* !CONFIG_XEN */
#define pfn_to_mfn(pfn) (pfn)
#define mfn_to_pfn(mfn) (mfn)
#define mfn_to_local_pfn(mfn) (mfn)
#define set_phys_to_machine(pfn, mfn) ((void)0)
#define phys_to_machine_mapping_valid(pfn) (1)
#define phys_to_machine(phys) ((maddr_t)(phys))
#define machine_to_phys(mach) ((paddr_t)(mach))
#endif /* !CONFIG_XEN */
/* VIRT <-> MACHINE conversion */
#define virt_to_machine(v) (phys_to_machine(__pa(v)))
#define virt_to_mfn(v) (pfn_to_mfn(__pa(v) >> PAGE_SHIFT))
#define mfn_to_virt(m) (__va(mfn_to_pfn(m) << PAGE_SHIFT))
#define __pte_ma(x) ((pte_t) { (x) } )
#define pfn_pte_ma(pfn, prot) __pte_ma((((pfn) << PAGE_SHIFT) | pgprot_val(prot)) & __supported_pte_mask)
#endif /* _X86_64_MADDR_H */
|
