page.h 7.1 KB

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  1. #ifndef _ASM_X86_XEN_PAGE_H
  2. #define _ASM_X86_XEN_PAGE_H
  3. #include <linux/kernel.h>
  4. #include <linux/types.h>
  5. #include <linux/spinlock.h>
  6. #include <linux/pfn.h>
  7. #include <linux/mm.h>
  8. #include <asm/uaccess.h>
  9. #include <asm/page.h>
  10. #include <asm/pgtable.h>
  11. #include <xen/interface/xen.h>
  12. #include <xen/grant_table.h>
  13. #include <xen/features.h>
  14. /* Xen machine address */
  15. typedef struct xmaddr {
  16. phys_addr_t maddr;
  17. } xmaddr_t;
  18. /* Xen pseudo-physical address */
  19. typedef struct xpaddr {
  20. phys_addr_t paddr;
  21. } xpaddr_t;
  22. #define XMADDR(x) ((xmaddr_t) { .maddr = (x) })
  23. #define XPADDR(x) ((xpaddr_t) { .paddr = (x) })
  24. /**** MACHINE <-> PHYSICAL CONVERSION MACROS ****/
  25. #define INVALID_P2M_ENTRY (~0UL)
  26. #define FOREIGN_FRAME_BIT (1UL<<(BITS_PER_LONG-1))
  27. #define IDENTITY_FRAME_BIT (1UL<<(BITS_PER_LONG-2))
  28. #define FOREIGN_FRAME(m) ((m) | FOREIGN_FRAME_BIT)
  29. #define IDENTITY_FRAME(m) ((m) | IDENTITY_FRAME_BIT)
  30. /* Maximum amount of memory we can handle in a domain in pages */
  31. #define MAX_DOMAIN_PAGES \
  32. ((unsigned long)((u64)CONFIG_XEN_MAX_DOMAIN_MEMORY * 1024 * 1024 * 1024 / PAGE_SIZE))
  33. extern unsigned long *machine_to_phys_mapping;
  34. extern unsigned long machine_to_phys_nr;
  35. extern unsigned long get_phys_to_machine(unsigned long pfn);
  36. extern bool set_phys_to_machine(unsigned long pfn, unsigned long mfn);
  37. extern bool __init early_set_phys_to_machine(unsigned long pfn, unsigned long mfn);
  38. extern bool __set_phys_to_machine(unsigned long pfn, unsigned long mfn);
  39. extern unsigned long set_phys_range_identity(unsigned long pfn_s,
  40. unsigned long pfn_e);
  41. extern int set_foreign_p2m_mapping(struct gnttab_map_grant_ref *map_ops,
  42. struct gnttab_map_grant_ref *kmap_ops,
  43. struct page **pages, unsigned int count);
  44. extern int m2p_add_override(unsigned long mfn, struct page *page,
  45. struct gnttab_map_grant_ref *kmap_op);
  46. extern int clear_foreign_p2m_mapping(struct gnttab_unmap_grant_ref *unmap_ops,
  47. struct gnttab_map_grant_ref *kmap_ops,
  48. struct page **pages, unsigned int count);
  49. extern int m2p_remove_override(struct page *page,
  50. struct gnttab_map_grant_ref *kmap_op,
  51. unsigned long mfn);
  52. extern struct page *m2p_find_override(unsigned long mfn);
  53. extern unsigned long m2p_find_override_pfn(unsigned long mfn, unsigned long pfn);
  54. static inline unsigned long pfn_to_mfn(unsigned long pfn)
  55. {
  56. unsigned long mfn;
  57. if (xen_feature(XENFEAT_auto_translated_physmap))
  58. return pfn;
  59. mfn = get_phys_to_machine(pfn);
  60. if (mfn != INVALID_P2M_ENTRY)
  61. mfn &= ~(FOREIGN_FRAME_BIT | IDENTITY_FRAME_BIT);
  62. return mfn;
  63. }
  64. static inline int phys_to_machine_mapping_valid(unsigned long pfn)
  65. {
  66. if (xen_feature(XENFEAT_auto_translated_physmap))
  67. return 1;
  68. return get_phys_to_machine(pfn) != INVALID_P2M_ENTRY;
  69. }
  70. static inline unsigned long mfn_to_pfn_no_overrides(unsigned long mfn)
  71. {
  72. unsigned long pfn;
  73. int ret;
  74. if (xen_feature(XENFEAT_auto_translated_physmap))
  75. return mfn;
  76. if (unlikely(mfn >= machine_to_phys_nr))
  77. return ~0;
  78. /*
  79. * The array access can fail (e.g., device space beyond end of RAM).
  80. * In such cases it doesn't matter what we return (we return garbage),
  81. * but we must handle the fault without crashing!
  82. */
  83. ret = __get_user(pfn, &machine_to_phys_mapping[mfn]);
  84. if (ret < 0)
  85. return ~0;
  86. return pfn;
  87. }
  88. static inline unsigned long mfn_to_pfn(unsigned long mfn)
  89. {
  90. unsigned long pfn;
  91. if (xen_feature(XENFEAT_auto_translated_physmap))
  92. return mfn;
  93. pfn = mfn_to_pfn_no_overrides(mfn);
  94. if (get_phys_to_machine(pfn) != mfn) {
  95. /*
  96. * If this appears to be a foreign mfn (because the pfn
  97. * doesn't map back to the mfn), then check the local override
  98. * table to see if there's a better pfn to use.
  99. *
  100. * m2p_find_override_pfn returns ~0 if it doesn't find anything.
  101. */
  102. pfn = m2p_find_override_pfn(mfn, ~0);
  103. }
  104. /*
  105. * pfn is ~0 if there are no entries in the m2p for mfn or if the
  106. * entry doesn't map back to the mfn and m2p_override doesn't have a
  107. * valid entry for it.
  108. */
  109. if (pfn == ~0 &&
  110. get_phys_to_machine(mfn) == IDENTITY_FRAME(mfn))
  111. pfn = mfn;
  112. return pfn;
  113. }
  114. static inline xmaddr_t phys_to_machine(xpaddr_t phys)
  115. {
  116. unsigned offset = phys.paddr & ~PAGE_MASK;
  117. return XMADDR(PFN_PHYS(pfn_to_mfn(PFN_DOWN(phys.paddr))) | offset);
  118. }
  119. static inline xpaddr_t machine_to_phys(xmaddr_t machine)
  120. {
  121. unsigned offset = machine.maddr & ~PAGE_MASK;
  122. return XPADDR(PFN_PHYS(mfn_to_pfn(PFN_DOWN(machine.maddr))) | offset);
  123. }
  124. /*
  125. * We detect special mappings in one of two ways:
  126. * 1. If the MFN is an I/O page then Xen will set the m2p entry
  127. * to be outside our maximum possible pseudophys range.
  128. * 2. If the MFN belongs to a different domain then we will certainly
  129. * not have MFN in our p2m table. Conversely, if the page is ours,
  130. * then we'll have p2m(m2p(MFN))==MFN.
  131. * If we detect a special mapping then it doesn't have a 'struct page'.
  132. * We force !pfn_valid() by returning an out-of-range pointer.
  133. *
  134. * NB. These checks require that, for any MFN that is not in our reservation,
  135. * there is no PFN such that p2m(PFN) == MFN. Otherwise we can get confused if
  136. * we are foreign-mapping the MFN, and the other domain as m2p(MFN) == PFN.
  137. * Yikes! Various places must poke in INVALID_P2M_ENTRY for safety.
  138. *
  139. * NB2. When deliberately mapping foreign pages into the p2m table, you *must*
  140. * use FOREIGN_FRAME(). This will cause pte_pfn() to choke on it, as we
  141. * require. In all the cases we care about, the FOREIGN_FRAME bit is
  142. * masked (e.g., pfn_to_mfn()) so behaviour there is correct.
  143. */
  144. static inline unsigned long mfn_to_local_pfn(unsigned long mfn)
  145. {
  146. unsigned long pfn;
  147. if (xen_feature(XENFEAT_auto_translated_physmap))
  148. return mfn;
  149. pfn = mfn_to_pfn(mfn);
  150. if (get_phys_to_machine(pfn) != mfn)
  151. return -1; /* force !pfn_valid() */
  152. return pfn;
  153. }
  154. /* VIRT <-> MACHINE conversion */
  155. #define virt_to_machine(v) (phys_to_machine(XPADDR(__pa(v))))
  156. #define virt_to_pfn(v) (PFN_DOWN(__pa(v)))
  157. #define virt_to_mfn(v) (pfn_to_mfn(virt_to_pfn(v)))
  158. #define mfn_to_virt(m) (__va(mfn_to_pfn(m) << PAGE_SHIFT))
  159. static inline unsigned long pte_mfn(pte_t pte)
  160. {
  161. return (pte.pte & PTE_PFN_MASK) >> PAGE_SHIFT;
  162. }
  163. static inline pte_t mfn_pte(unsigned long page_nr, pgprot_t pgprot)
  164. {
  165. pte_t pte;
  166. pte.pte = ((phys_addr_t)page_nr << PAGE_SHIFT) |
  167. massage_pgprot(pgprot);
  168. return pte;
  169. }
  170. static inline pteval_t pte_val_ma(pte_t pte)
  171. {
  172. return pte.pte;
  173. }
  174. static inline pte_t __pte_ma(pteval_t x)
  175. {
  176. return (pte_t) { .pte = x };
  177. }
  178. #define pmd_val_ma(v) ((v).pmd)
  179. #ifdef __PAGETABLE_PUD_FOLDED
  180. #define pud_val_ma(v) ((v).pgd.pgd)
  181. #else
  182. #define pud_val_ma(v) ((v).pud)
  183. #endif
  184. #define __pmd_ma(x) ((pmd_t) { (x) } )
  185. #define pgd_val_ma(x) ((x).pgd)
  186. void xen_set_domain_pte(pte_t *ptep, pte_t pteval, unsigned domid);
  187. xmaddr_t arbitrary_virt_to_machine(void *address);
  188. unsigned long arbitrary_virt_to_mfn(void *vaddr);
  189. void make_lowmem_page_readonly(void *vaddr);
  190. void make_lowmem_page_readwrite(void *vaddr);
  191. #define xen_remap(cookie, size) ioremap((cookie), (size));
  192. #define xen_unmap(cookie) iounmap((cookie))
  193. static inline bool xen_arch_need_swiotlb(struct device *dev,
  194. unsigned long pfn,
  195. unsigned long mfn)
  196. {
  197. return false;
  198. }
  199. #endif /* _ASM_X86_XEN_PAGE_H */