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-rw-r--r--include/xen/page.h181
1 files changed, 1 insertions, 180 deletions
diff --git a/include/xen/page.h b/include/xen/page.h
index 031ef22a971e..eaf85fab1263 100644
--- a/include/xen/page.h
+++ b/include/xen/page.h
@@ -1,180 +1 @@
1#ifndef __XEN_PAGE_H #include <asm/xen/page.h>
2#define __XEN_PAGE_H
3
4#include <linux/pfn.h>
5
6#include <asm/uaccess.h>
7#include <asm/pgtable.h>
8
9#include <xen/features.h>
10
11#ifdef CONFIG_X86_PAE
12/* Xen machine address */
13typedef struct xmaddr {
14 unsigned long long maddr;
15} xmaddr_t;
16
17/* Xen pseudo-physical address */
18typedef struct xpaddr {
19 unsigned long long paddr;
20} xpaddr_t;
21#else
22/* Xen machine address */
23typedef struct xmaddr {
24 unsigned long maddr;
25} xmaddr_t;
26
27/* Xen pseudo-physical address */
28typedef struct xpaddr {
29 unsigned long paddr;
30} xpaddr_t;
31#endif
32
33#define XMADDR(x) ((xmaddr_t) { .maddr = (x) })
34#define XPADDR(x) ((xpaddr_t) { .paddr = (x) })
35
36/**** MACHINE <-> PHYSICAL CONVERSION MACROS ****/
37#define INVALID_P2M_ENTRY (~0UL)
38#define FOREIGN_FRAME_BIT (1UL<<31)
39#define FOREIGN_FRAME(m) ((m) | FOREIGN_FRAME_BIT)
40
41extern unsigned long *phys_to_machine_mapping;
42
43static inline unsigned long pfn_to_mfn(unsigned long pfn)
44{
45 if (xen_feature(XENFEAT_auto_translated_physmap))
46 return pfn;
47
48 return phys_to_machine_mapping[(unsigned int)(pfn)] &
49 ~FOREIGN_FRAME_BIT;
50}
51
52static inline int phys_to_machine_mapping_valid(unsigned long pfn)
53{
54 if (xen_feature(XENFEAT_auto_translated_physmap))
55 return 1;
56
57 return (phys_to_machine_mapping[pfn] != INVALID_P2M_ENTRY);
58}
59
60static inline unsigned long mfn_to_pfn(unsigned long mfn)
61{
62 unsigned long pfn;
63
64 if (xen_feature(XENFEAT_auto_translated_physmap))
65 return mfn;
66
67#if 0
68 if (unlikely((mfn >> machine_to_phys_order) != 0))
69 return max_mapnr;
70#endif
71
72 pfn = 0;
73 /*
74 * The array access can fail (e.g., device space beyond end of RAM).
75 * In such cases it doesn't matter what we return (we return garbage),
76 * but we must handle the fault without crashing!
77 */
78 __get_user(pfn, &machine_to_phys_mapping[mfn]);
79
80 return pfn;
81}
82
83static inline xmaddr_t phys_to_machine(xpaddr_t phys)
84{
85 unsigned offset = phys.paddr & ~PAGE_MASK;
86 return XMADDR(PFN_PHYS((u64)pfn_to_mfn(PFN_DOWN(phys.paddr))) | offset);
87}
88
89static inline xpaddr_t machine_to_phys(xmaddr_t machine)
90{
91 unsigned offset = machine.maddr & ~PAGE_MASK;
92 return XPADDR(PFN_PHYS((u64)mfn_to_pfn(PFN_DOWN(machine.maddr))) | offset);
93}
94
95/*
96 * We detect special mappings in one of two ways:
97 * 1. If the MFN is an I/O page then Xen will set the m2p entry
98 * to be outside our maximum possible pseudophys range.
99 * 2. If the MFN belongs to a different domain then we will certainly
100 * not have MFN in our p2m table. Conversely, if the page is ours,
101 * then we'll have p2m(m2p(MFN))==MFN.
102 * If we detect a special mapping then it doesn't have a 'struct page'.
103 * We force !pfn_valid() by returning an out-of-range pointer.
104 *
105 * NB. These checks require that, for any MFN that is not in our reservation,
106 * there is no PFN such that p2m(PFN) == MFN. Otherwise we can get confused if
107 * we are foreign-mapping the MFN, and the other domain as m2p(MFN) == PFN.
108 * Yikes! Various places must poke in INVALID_P2M_ENTRY for safety.
109 *
110 * NB2. When deliberately mapping foreign pages into the p2m table, you *must*
111 * use FOREIGN_FRAME(). This will cause pte_pfn() to choke on it, as we
112 * require. In all the cases we care about, the FOREIGN_FRAME bit is
113 * masked (e.g., pfn_to_mfn()) so behaviour there is correct.
114 */
115static inline unsigned long mfn_to_local_pfn(unsigned long mfn)
116{
117 extern unsigned long max_mapnr;
118 unsigned long pfn = mfn_to_pfn(mfn);
119 if ((pfn < max_mapnr)
120 && !xen_feature(XENFEAT_auto_translated_physmap)
121 && (phys_to_machine_mapping[pfn] != mfn))
122 return max_mapnr; /* force !pfn_valid() */
123 return pfn;
124}
125
126static inline void set_phys_to_machine(unsigned long pfn, unsigned long mfn)
127{
128 if (xen_feature(XENFEAT_auto_translated_physmap)) {
129 BUG_ON(pfn != mfn && mfn != INVALID_P2M_ENTRY);
130 return;
131 }
132 phys_to_machine_mapping[pfn] = mfn;
133}
134
135/* VIRT <-> MACHINE conversion */
136#define virt_to_machine(v) (phys_to_machine(XPADDR(__pa(v))))
137#define virt_to_mfn(v) (pfn_to_mfn(PFN_DOWN(__pa(v))))
138#define mfn_to_virt(m) (__va(mfn_to_pfn(m) << PAGE_SHIFT))
139
140#ifdef CONFIG_X86_PAE
141#define pte_mfn(_pte) (((_pte).pte_low >> PAGE_SHIFT) | \
142 (((_pte).pte_high & 0xfff) << (32-PAGE_SHIFT)))
143
144static inline pte_t mfn_pte(unsigned long page_nr, pgprot_t pgprot)
145{
146 pte_t pte;
147
148 pte.pte_high = (page_nr >> (32 - PAGE_SHIFT)) |
149 (pgprot_val(pgprot) >> 32);
150 pte.pte_high &= (__supported_pte_mask >> 32);
151 pte.pte_low = ((page_nr << PAGE_SHIFT) | pgprot_val(pgprot));
152 pte.pte_low &= __supported_pte_mask;
153
154 return pte;
155}
156
157static inline unsigned long long pte_val_ma(pte_t x)
158{
159 return x.pte;
160}
161#define pmd_val_ma(v) ((v).pmd)
162#define pud_val_ma(v) ((v).pgd.pgd)
163#define __pte_ma(x) ((pte_t) { .pte = (x) })
164#define __pmd_ma(x) ((pmd_t) { (x) } )
165#else /* !X86_PAE */
166#define pte_mfn(_pte) ((_pte).pte_low >> PAGE_SHIFT)
167#define mfn_pte(pfn, prot) __pte_ma(((pfn) << PAGE_SHIFT) | pgprot_val(prot))
168#define pte_val_ma(x) ((x).pte)
169#define pmd_val_ma(v) ((v).pud.pgd.pgd)
170#define __pte_ma(x) ((pte_t) { (x) } )
171#endif /* CONFIG_X86_PAE */
172
173#define pgd_val_ma(x) ((x).pgd)
174
175
176xmaddr_t arbitrary_virt_to_machine(unsigned long address);
177void make_lowmem_page_readonly(void *vaddr);
178void make_lowmem_page_readwrite(void *vaddr);
179
180#endif /* __XEN_PAGE_H */
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