memory_model.h 1.4 KB

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  1. /* SPDX-License-Identifier: GPL-2.0 */
  2. #ifndef __ASM_MEMORY_MODEL_H
  3. #define __ASM_MEMORY_MODEL_H
  4. #include <linux/pfn.h>
  5. #ifndef __ASSEMBLY__
  6. /*
  7. * supports 3 memory models.
  8. */
  9. #if defined(CONFIG_FLATMEM)
  10. #ifndef ARCH_PFN_OFFSET
  11. #define ARCH_PFN_OFFSET (0UL)
  12. #endif
  13. #define __pfn_to_page(pfn) (mem_map + ((pfn) - ARCH_PFN_OFFSET))
  14. #define __page_to_pfn(page) ((unsigned long)((page) - mem_map) + \
  15. ARCH_PFN_OFFSET)
  16. #elif defined(CONFIG_SPARSEMEM_VMEMMAP)
  17. /* memmap is virtually contiguous. */
  18. #define __pfn_to_page(pfn) (vmemmap + (pfn))
  19. #define __page_to_pfn(page) (unsigned long)((page) - vmemmap)
  20. #elif defined(CONFIG_SPARSEMEM)
  21. /*
  22. * Note: section's mem_map is encoded to reflect its start_pfn.
  23. * section[i].section_mem_map == mem_map's address - start_pfn;
  24. */
  25. #define __page_to_pfn(pg) \
  26. ({ const struct page *__pg = (pg); \
  27. int __sec = page_to_section(__pg); \
  28. (unsigned long)(__pg - __section_mem_map_addr(__nr_to_section(__sec))); \
  29. })
  30. #define __pfn_to_page(pfn) \
  31. ({ unsigned long __pfn = (pfn); \
  32. struct mem_section *__sec = __pfn_to_section(__pfn); \
  33. __section_mem_map_addr(__sec) + __pfn; \
  34. })
  35. #endif /* CONFIG_FLATMEM/SPARSEMEM */
  36. /*
  37. * Convert a physical address to a Page Frame Number and back
  38. */
  39. #define __phys_to_pfn(paddr) PHYS_PFN(paddr)
  40. #define __pfn_to_phys(pfn) PFN_PHYS(pfn)
  41. #define page_to_pfn __page_to_pfn
  42. #define pfn_to_page __pfn_to_page
  43. #endif /* __ASSEMBLY__ */
  44. #endif