4 #include <xen/features.h>
5 #include <xen/interface/xen.h>
7 /**** MACHINE <-> PHYSICAL CONVERSION MACROS ****/
8 #define INVALID_P2M_ENTRY (~0UL)
9 #define FOREIGN_FRAME_BIT (1UL<<31)
10 #define FOREIGN_FRAME(m) ((m) | FOREIGN_FRAME_BIT)
12 /* Definitions for machine and pseudophysical addresses. */
14 typedef unsigned long long paddr_t;
15 typedef unsigned long long maddr_t;
17 typedef unsigned long paddr_t;
18 typedef unsigned long maddr_t;
23 extern unsigned long *phys_to_machine_mapping;
24 extern unsigned long max_mapnr;
26 #undef machine_to_phys_mapping
27 extern unsigned long *machine_to_phys_mapping;
28 extern unsigned int machine_to_phys_order;
30 static inline unsigned long pfn_to_mfn(unsigned long pfn)
32 if (xen_feature(XENFEAT_auto_translated_physmap))
34 BUG_ON(max_mapnr && pfn >= max_mapnr);
35 return phys_to_machine_mapping[pfn] & ~FOREIGN_FRAME_BIT;
38 static inline int phys_to_machine_mapping_valid(unsigned long pfn)
40 if (xen_feature(XENFEAT_auto_translated_physmap))
42 BUG_ON(max_mapnr && pfn >= max_mapnr);
43 return (phys_to_machine_mapping[pfn] != INVALID_P2M_ENTRY);
46 static inline unsigned long mfn_to_pfn(unsigned long mfn)
50 if (xen_feature(XENFEAT_auto_translated_physmap))
53 if (unlikely((mfn >> machine_to_phys_order) != 0))
56 /* The array access can fail (e.g., device space beyond end of RAM). */
60 ".section .fixup,\"ax\"\n"
64 ".section __ex_table,\"a\"\n"
69 : "m" (machine_to_phys_mapping[mfn]), "m" (max_mapnr) );
75 * We detect special mappings in one of two ways:
76 * 1. If the MFN is an I/O page then Xen will set the m2p entry
77 * to be outside our maximum possible pseudophys range.
78 * 2. If the MFN belongs to a different domain then we will certainly
79 * not have MFN in our p2m table. Conversely, if the page is ours,
80 * then we'll have p2m(m2p(MFN))==MFN.
81 * If we detect a special mapping then it doesn't have a 'struct page'.
82 * We force !pfn_valid() by returning an out-of-range pointer.
84 * NB. These checks require that, for any MFN that is not in our reservation,
85 * there is no PFN such that p2m(PFN) == MFN. Otherwise we can get confused if
86 * we are foreign-mapping the MFN, and the other domain as m2p(MFN) == PFN.
87 * Yikes! Various places must poke in INVALID_P2M_ENTRY for safety.
89 * NB2. When deliberately mapping foreign pages into the p2m table, you *must*
90 * use FOREIGN_FRAME(). This will cause pte_pfn() to choke on it, as we
91 * require. In all the cases we care about, the FOREIGN_FRAME bit is
92 * masked (e.g., pfn_to_mfn()) so behaviour there is correct.
94 static inline unsigned long mfn_to_local_pfn(unsigned long mfn)
96 unsigned long pfn = mfn_to_pfn(mfn);
98 && !xen_feature(XENFEAT_auto_translated_physmap)
99 && (phys_to_machine_mapping[pfn] != mfn))
100 return max_mapnr; /* force !pfn_valid() */
104 static inline void set_phys_to_machine(unsigned long pfn, unsigned long mfn)
106 BUG_ON(max_mapnr && pfn >= max_mapnr);
107 if (xen_feature(XENFEAT_auto_translated_physmap)) {
108 BUG_ON(pfn != mfn && mfn != INVALID_P2M_ENTRY);
111 phys_to_machine_mapping[pfn] = mfn;
114 static inline maddr_t phys_to_machine(paddr_t phys)
116 maddr_t machine = pfn_to_mfn(phys >> PAGE_SHIFT);
117 machine = (machine << PAGE_SHIFT) | (phys & ~PAGE_MASK);
121 static inline paddr_t machine_to_phys(maddr_t machine)
123 paddr_t phys = mfn_to_pfn(machine >> PAGE_SHIFT);
124 phys = (phys << PAGE_SHIFT) | (machine & ~PAGE_MASK);
128 #ifdef CONFIG_X86_PAE
129 static inline paddr_t pte_phys_to_machine(paddr_t phys)
132 * In PAE mode, the NX bit needs to be dealt with in the value
133 * passed to pfn_to_mfn(). On x86_64, we need to mask it off,
134 * but for i386 the conversion to ulong for the argument will
137 maddr_t machine = pfn_to_mfn(phys >> PAGE_SHIFT);
138 machine = (machine << PAGE_SHIFT) | (phys & ~PHYSICAL_PAGE_MASK);
142 static inline paddr_t pte_machine_to_phys(maddr_t machine)
145 * In PAE mode, the NX bit needs to be dealt with in the value
146 * passed to mfn_to_pfn(). On x86_64, we need to mask it off,
147 * but for i386 the conversion to ulong for the argument will
150 paddr_t phys = mfn_to_pfn(machine >> PAGE_SHIFT);
151 phys = (phys << PAGE_SHIFT) | (machine & ~PHYSICAL_PAGE_MASK);
156 #ifdef CONFIG_X86_PAE
157 extern unsigned long long __supported_pte_mask;
158 static inline pte_t pfn_pte_ma(unsigned long page_nr, pgprot_t pgprot)
162 pte.pte_high = (page_nr >> (32 - PAGE_SHIFT)) | \
163 (pgprot_val(pgprot) >> 32);
164 pte.pte_high &= (__supported_pte_mask >> 32);
165 pte.pte_low = ((page_nr << PAGE_SHIFT) | pgprot_val(pgprot)) & \
166 __supported_pte_mask;
170 #define pfn_pte_ma(pfn, prot) __pte_ma(((pfn) << PAGE_SHIFT) | pgprot_val(prot))
173 #define __pte_ma(x) ((pte_t) { (x) } )
175 #else /* !CONFIG_XEN */
177 #define pfn_to_mfn(pfn) (pfn)
178 #define mfn_to_pfn(mfn) (mfn)
179 #define mfn_to_local_pfn(mfn) (mfn)
180 #define set_phys_to_machine(pfn, mfn) ((void)0)
181 #define phys_to_machine_mapping_valid(pfn) (1)
182 #define phys_to_machine(phys) ((maddr_t)(phys))
183 #define machine_to_phys(mach) ((paddr_t)(mach))
184 #define pfn_pte_ma(pfn, prot) pfn_pte(pfn, prot)
185 #define __pte_ma(x) __pte(x)
187 #endif /* !CONFIG_XEN */
189 /* VIRT <-> MACHINE conversion */
190 #define virt_to_machine(v) (phys_to_machine(__pa(v)))
191 #define virt_to_mfn(v) (pfn_to_mfn(__pa(v) >> PAGE_SHIFT))
192 #define mfn_to_virt(m) (__va(mfn_to_pfn(m) << PAGE_SHIFT))
194 #endif /* _I386_MADDR_H */