-/**** MACHINE <-> PHYSICAL CONVERSION MACROS ****/
-#define INVALID_P2M_ENTRY (~0UL)
-#define FOREIGN_FRAME_BIT (1UL<<31)
-#define FOREIGN_FRAME(m) ((m) | FOREIGN_FRAME_BIT)
-
-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;
- return phys_to_machine_mapping[(unsigned int)(pfn)] &
- ~FOREIGN_FRAME_BIT;
-}
-
-static inline int phys_to_machine_mapping_valid(unsigned long pfn)
-{
- if (xen_feature(XENFEAT_auto_translated_physmap))
- return 1;
- return (phys_to_machine_mapping[pfn] != INVALID_P2M_ENTRY);
-}
-
-static inline unsigned long mfn_to_pfn(unsigned long mfn)
-{
- extern unsigned long max_mapnr;
- unsigned long pfn;
-
- if (xen_feature(XENFEAT_auto_translated_physmap))
- return mfn;
-
- if (unlikely((mfn >> machine_to_phys_order) != 0))
- return max_mapnr;
-
- /* The array access can fail (e.g., device space beyond end of RAM). */
- asm (
- "1: movl %1,%0\n"
- "2:\n"
- ".section .fixup,\"ax\"\n"
- "3: movl %2,%0\n"
- " jmp 2b\n"
- ".previous\n"
- ".section __ex_table,\"a\"\n"
- " .align 4\n"
- " .long 1b,3b\n"
- ".previous"
- : "=r" (pfn)
- : "m" (machine_to_phys_mapping[mfn]), "m" (max_mapnr) );
-
- 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)
-{
- extern unsigned long max_mapnr;
- unsigned long pfn = mfn_to_pfn(mfn);
- if ((pfn < max_mapnr)
- && !xen_feature(XENFEAT_auto_translated_physmap)
- && (phys_to_machine_mapping[pfn] != mfn))
- return max_mapnr; /* force !pfn_valid() */
- return pfn;
-}
-
-static inline void set_phys_to_machine(unsigned long pfn, unsigned long mfn)
-{
- if (xen_feature(XENFEAT_auto_translated_physmap)) {
- BUG_ON(pfn != mfn && mfn != INVALID_P2M_ENTRY);
- return;
- }
- phys_to_machine_mapping[pfn] = mfn;
-}
-
-/* Definitions for machine and pseudophysical addresses. */
-#ifdef CONFIG_X86_PAE
-typedef unsigned long long paddr_t;
-typedef unsigned long long maddr_t;
-#else
-typedef unsigned long paddr_t;
-typedef unsigned long maddr_t;
-#endif
-
-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;
-}
-