6 #include <asm/uaccess.h>
8 #include <xen/features.h>
11 /* Xen machine address */
12 typedef struct xmaddr
{
13 unsigned long long maddr
;
16 /* Xen pseudo-physical address */
17 typedef struct xpaddr
{
18 unsigned long long paddr
;
21 /* Xen machine address */
22 typedef struct xmaddr
{
26 /* Xen pseudo-physical address */
27 typedef struct xpaddr
{
32 #define XMADDR(x) ((xmaddr_t) { .maddr = (x) })
33 #define XPADDR(x) ((xpaddr_t) { .paddr = (x) })
35 /**** MACHINE <-> PHYSICAL CONVERSION MACROS ****/
36 #define INVALID_P2M_ENTRY (~0UL)
37 #define FOREIGN_FRAME_BIT (1UL<<31)
38 #define FOREIGN_FRAME(m) ((m) | FOREIGN_FRAME_BIT)
40 extern unsigned long *phys_to_machine_mapping
;
42 static inline unsigned long pfn_to_mfn(unsigned long pfn
)
44 if (xen_feature(XENFEAT_auto_translated_physmap
))
47 return phys_to_machine_mapping
[(unsigned int)(pfn
)] &
51 static inline int phys_to_machine_mapping_valid(unsigned long pfn
)
53 if (xen_feature(XENFEAT_auto_translated_physmap
))
56 return (phys_to_machine_mapping
[pfn
] != INVALID_P2M_ENTRY
);
59 static inline unsigned long mfn_to_pfn(unsigned long mfn
)
63 if (xen_feature(XENFEAT_auto_translated_physmap
))
67 if (unlikely((mfn
>> machine_to_phys_order
) != 0))
73 * The array access can fail (e.g., device space beyond end of RAM).
74 * In such cases it doesn't matter what we return (we return garbage),
75 * but we must handle the fault without crashing!
77 __get_user(pfn
, &machine_to_phys_mapping
[mfn
]);
82 static inline xmaddr_t
phys_to_machine(xpaddr_t phys
)
84 unsigned offset
= phys
.paddr
& ~PAGE_MASK
;
85 return XMADDR(PFN_PHYS((u64
)pfn_to_mfn(PFN_DOWN(phys
.paddr
))) | offset
);
88 static inline xpaddr_t
machine_to_phys(xmaddr_t machine
)
90 unsigned offset
= machine
.maddr
& ~PAGE_MASK
;
91 return XPADDR(PFN_PHYS((u64
)mfn_to_pfn(PFN_DOWN(machine
.maddr
))) | offset
);
95 * We detect special mappings in one of two ways:
96 * 1. If the MFN is an I/O page then Xen will set the m2p entry
97 * to be outside our maximum possible pseudophys range.
98 * 2. If the MFN belongs to a different domain then we will certainly
99 * not have MFN in our p2m table. Conversely, if the page is ours,
100 * then we'll have p2m(m2p(MFN))==MFN.
101 * If we detect a special mapping then it doesn't have a 'struct page'.
102 * We force !pfn_valid() by returning an out-of-range pointer.
104 * NB. These checks require that, for any MFN that is not in our reservation,
105 * there is no PFN such that p2m(PFN) == MFN. Otherwise we can get confused if
106 * we are foreign-mapping the MFN, and the other domain as m2p(MFN) == PFN.
107 * Yikes! Various places must poke in INVALID_P2M_ENTRY for safety.
109 * NB2. When deliberately mapping foreign pages into the p2m table, you *must*
110 * use FOREIGN_FRAME(). This will cause pte_pfn() to choke on it, as we
111 * require. In all the cases we care about, the FOREIGN_FRAME bit is
112 * masked (e.g., pfn_to_mfn()) so behaviour there is correct.
114 static inline unsigned long mfn_to_local_pfn(unsigned long mfn
)
116 extern unsigned long max_mapnr
;
117 unsigned long pfn
= mfn_to_pfn(mfn
);
118 if ((pfn
< max_mapnr
)
119 && !xen_feature(XENFEAT_auto_translated_physmap
)
120 && (phys_to_machine_mapping
[pfn
] != mfn
))
121 return max_mapnr
; /* force !pfn_valid() */
125 static inline void set_phys_to_machine(unsigned long pfn
, unsigned long mfn
)
127 if (xen_feature(XENFEAT_auto_translated_physmap
)) {
128 BUG_ON(pfn
!= mfn
&& mfn
!= INVALID_P2M_ENTRY
);
131 phys_to_machine_mapping
[pfn
] = mfn
;
134 /* VIRT <-> MACHINE conversion */
135 #define virt_to_machine(v) (phys_to_machine(XPADDR(__pa(v))))
136 #define virt_to_mfn(v) (pfn_to_mfn(PFN_DOWN(__pa(v))))
137 #define mfn_to_virt(m) (__va(mfn_to_pfn(m) << PAGE_SHIFT))
139 #ifdef CONFIG_X86_PAE
140 #define pte_mfn(_pte) (((_pte).pte_low >> PAGE_SHIFT) | \
141 (((_pte).pte_high & 0xfff) << (32-PAGE_SHIFT)))
143 static inline pte_t
mfn_pte(unsigned long page_nr
, pgprot_t pgprot
)
147 pte
.pte_high
= (page_nr
>> (32 - PAGE_SHIFT
)) |
148 (pgprot_val(pgprot
) >> 32);
149 pte
.pte_high
&= (__supported_pte_mask
>> 32);
150 pte
.pte_low
= ((page_nr
<< PAGE_SHIFT
) | pgprot_val(pgprot
));
151 pte
.pte_low
&= __supported_pte_mask
;
156 static inline unsigned long long pte_val_ma(pte_t x
)
158 return ((unsigned long long)x
.pte_high
<< 32) | x
.pte_low
;
160 #define pmd_val_ma(v) ((v).pmd)
161 #define pud_val_ma(v) ((v).pgd.pgd)
162 #define __pte_ma(x) ((pte_t) { .pte_low = (x), .pte_high = (x)>>32 } )
163 #define __pmd_ma(x) ((pmd_t) { (x) } )
165 #define pte_mfn(_pte) ((_pte).pte_low >> PAGE_SHIFT)
166 #define mfn_pte(pfn, prot) __pte_ma(((pfn) << PAGE_SHIFT) | pgprot_val(prot))
167 #define pte_val_ma(x) ((x).pte_low)
168 #define pmd_val_ma(v) ((v).pud.pgd.pgd)
169 #define __pte_ma(x) ((pte_t) { (x) } )
170 #endif /* CONFIG_X86_PAE */
172 #define pgd_val_ma(x) ((x).pgd)
175 xmaddr_t
arbitrary_virt_to_machine(unsigned long address
);
176 void make_lowmem_page_readonly(void *vaddr
);
177 void make_lowmem_page_readwrite(void *vaddr
);
179 #endif /* __XEN_PAGE_H */