Jeremy Fitzhardinge | 5ead97c | 2007-07-17 18:37:04 -0700 | [diff] [blame^] | 1 | #ifndef __XEN_PAGE_H |
| 2 | #define __XEN_PAGE_H |
| 3 | |
| 4 | #include <linux/pfn.h> |
| 5 | |
| 6 | #include <asm/uaccess.h> |
| 7 | |
| 8 | #include <xen/features.h> |
| 9 | |
| 10 | #ifdef CONFIG_X86_PAE |
| 11 | /* Xen machine address */ |
| 12 | typedef struct xmaddr { |
| 13 | unsigned long long maddr; |
| 14 | } xmaddr_t; |
| 15 | |
| 16 | /* Xen pseudo-physical address */ |
| 17 | typedef struct xpaddr { |
| 18 | unsigned long long paddr; |
| 19 | } xpaddr_t; |
| 20 | #else |
| 21 | /* Xen machine address */ |
| 22 | typedef struct xmaddr { |
| 23 | unsigned long maddr; |
| 24 | } xmaddr_t; |
| 25 | |
| 26 | /* Xen pseudo-physical address */ |
| 27 | typedef struct xpaddr { |
| 28 | unsigned long paddr; |
| 29 | } xpaddr_t; |
| 30 | #endif |
| 31 | |
| 32 | #define XMADDR(x) ((xmaddr_t) { .maddr = (x) }) |
| 33 | #define XPADDR(x) ((xpaddr_t) { .paddr = (x) }) |
| 34 | |
| 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) |
| 39 | |
| 40 | extern unsigned long *phys_to_machine_mapping; |
| 41 | |
| 42 | static inline unsigned long pfn_to_mfn(unsigned long pfn) |
| 43 | { |
| 44 | if (xen_feature(XENFEAT_auto_translated_physmap)) |
| 45 | return pfn; |
| 46 | |
| 47 | return phys_to_machine_mapping[(unsigned int)(pfn)] & |
| 48 | ~FOREIGN_FRAME_BIT; |
| 49 | } |
| 50 | |
| 51 | static inline int phys_to_machine_mapping_valid(unsigned long pfn) |
| 52 | { |
| 53 | if (xen_feature(XENFEAT_auto_translated_physmap)) |
| 54 | return 1; |
| 55 | |
| 56 | return (phys_to_machine_mapping[pfn] != INVALID_P2M_ENTRY); |
| 57 | } |
| 58 | |
| 59 | static inline unsigned long mfn_to_pfn(unsigned long mfn) |
| 60 | { |
| 61 | unsigned long pfn; |
| 62 | |
| 63 | if (xen_feature(XENFEAT_auto_translated_physmap)) |
| 64 | return mfn; |
| 65 | |
| 66 | #if 0 |
| 67 | if (unlikely((mfn >> machine_to_phys_order) != 0)) |
| 68 | return max_mapnr; |
| 69 | #endif |
| 70 | |
| 71 | pfn = 0; |
| 72 | /* |
| 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! |
| 76 | */ |
| 77 | __get_user(pfn, &machine_to_phys_mapping[mfn]); |
| 78 | |
| 79 | return pfn; |
| 80 | } |
| 81 | |
| 82 | static inline xmaddr_t phys_to_machine(xpaddr_t phys) |
| 83 | { |
| 84 | unsigned offset = phys.paddr & ~PAGE_MASK; |
| 85 | return XMADDR(PFN_PHYS((u64)pfn_to_mfn(PFN_DOWN(phys.paddr))) | offset); |
| 86 | } |
| 87 | |
| 88 | static inline xpaddr_t machine_to_phys(xmaddr_t machine) |
| 89 | { |
| 90 | unsigned offset = machine.maddr & ~PAGE_MASK; |
| 91 | return XPADDR(PFN_PHYS((u64)mfn_to_pfn(PFN_DOWN(machine.maddr))) | offset); |
| 92 | } |
| 93 | |
| 94 | /* |
| 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. |
| 103 | * |
| 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. |
| 108 | * |
| 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. |
| 113 | */ |
| 114 | static inline unsigned long mfn_to_local_pfn(unsigned long mfn) |
| 115 | { |
| 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() */ |
| 122 | return pfn; |
| 123 | } |
| 124 | |
| 125 | static inline void set_phys_to_machine(unsigned long pfn, unsigned long mfn) |
| 126 | { |
| 127 | if (xen_feature(XENFEAT_auto_translated_physmap)) { |
| 128 | BUG_ON(pfn != mfn && mfn != INVALID_P2M_ENTRY); |
| 129 | return; |
| 130 | } |
| 131 | phys_to_machine_mapping[pfn] = mfn; |
| 132 | } |
| 133 | |
| 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)) |
| 138 | |
| 139 | #ifdef CONFIG_X86_PAE |
| 140 | #define pte_mfn(_pte) (((_pte).pte_low >> PAGE_SHIFT) | \ |
| 141 | (((_pte).pte_high & 0xfff) << (32-PAGE_SHIFT))) |
| 142 | |
| 143 | static inline pte_t mfn_pte(unsigned long page_nr, pgprot_t pgprot) |
| 144 | { |
| 145 | pte_t pte; |
| 146 | |
| 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; |
| 152 | |
| 153 | return pte; |
| 154 | } |
| 155 | |
| 156 | static inline unsigned long long pte_val_ma(pte_t x) |
| 157 | { |
| 158 | return ((unsigned long long)x.pte_high << 32) | x.pte_low; |
| 159 | } |
| 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) } ) |
| 164 | #else /* !X86_PAE */ |
| 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 */ |
| 171 | |
| 172 | #define pgd_val_ma(x) ((x).pgd) |
| 173 | |
| 174 | |
| 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); |
| 178 | |
| 179 | #endif /* __XEN_PAGE_H */ |