#ifndef __XEN_PAGE_H #define __XEN_PAGE_H #include <linux/pfn.h> #include <asm/uaccess.h> #include <asm/pgtable.h> #include <xen/features.h> /* Xen machine address */ typedef struct xmaddr { phys_addr_t maddr; } xmaddr_t; /* Xen pseudo-physical address */ typedef struct xpaddr { phys_addr_t paddr; } xpaddr_t; #define XMADDR(x) ((xmaddr_t) { .maddr = (x) }) #define XPADDR(x) ((xpaddr_t) { .paddr = (x) }) /**** 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; 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) { unsigned long pfn; if (xen_feature(XENFEAT_auto_translated_physmap)) return mfn; #if 0 if (unlikely((mfn >> machine_to_phys_order) != 0)) return max_mapnr; #endif pfn = 0; /* * The array access can fail (e.g., device space beyond end of RAM). * In such cases it doesn't matter what we return (we return garbage), * but we must handle the fault without crashing! */ __get_user(pfn, &machine_to_phys_mapping[mfn]); return pfn; } static inline xmaddr_t phys_to_machine(xpaddr_t phys) { unsigned offset = phys.paddr & ~PAGE_MASK; return XMADDR(PFN_PHYS((u64)pfn_to_mfn(PFN_DOWN(phys.paddr))) | offset); } static inline xpaddr_t machine_to_phys(xmaddr_t machine) { unsigned offset = machine.maddr & ~PAGE_MASK; return XPADDR(PFN_PHYS((u64)mfn_to_pfn(PFN_DOWN(machine.maddr))) | offset); } /* * 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; } /* VIRT <-> MACHINE conversion */ #define virt_to_machine(v) (phys_to_machine(XPADDR(__pa(v)))) #define virt_to_mfn(v) (pfn_to_mfn(PFN_DOWN(__pa(v)))) #define mfn_to_virt(m) (__va(mfn_to_pfn(m) << PAGE_SHIFT)) static inline unsigned long pte_mfn(pte_t pte) { return (pte.pte & ~_PAGE_NX) >> PAGE_SHIFT; } static inline pte_t mfn_pte(unsigned long page_nr, pgprot_t pgprot) { pte_t pte; pte.pte = ((phys_addr_t)page_nr << PAGE_SHIFT) | (pgprot_val(pgprot) & __supported_pte_mask); return pte; } static inline pteval_t pte_val_ma(pte_t pte) { return pte.pte; } static inline pte_t __pte_ma(pteval_t x) { return (pte_t) { .pte = x }; } #ifdef CONFIG_X86_PAE #define pmd_val_ma(v) ((v).pmd) #define pud_val_ma(v) ((v).pgd.pgd) #define __pmd_ma(x) ((pmd_t) { (x) } ) #else /* !X86_PAE */ #define pmd_val_ma(v) ((v).pud.pgd.pgd) #endif /* CONFIG_X86_PAE */ #define pgd_val_ma(x) ((x).pgd) xmaddr_t arbitrary_virt_to_machine(unsigned long address); void make_lowmem_page_readonly(void *vaddr); void make_lowmem_page_readwrite(void *vaddr); #endif /* __XEN_PAGE_H */