Line data    Source code

       1             : /* SPDX-License-Identifier: GPL-2.0 */
       2             : #ifndef __ASM_MEMORY_MODEL_H
       3             : #define __ASM_MEMORY_MODEL_H
       4             : 
       5             : #include <linux/pfn.h>
       6             : 
       7             : #ifndef __ASSEMBLY__
       8             : 
       9             : /*
      10             :  * supports 3 memory models.
      11             :  */
      12             : #if defined(CONFIG_FLATMEM)
      13             : 
      14             : #ifndef ARCH_PFN_OFFSET
      15             : #define ARCH_PFN_OFFSET         (0UL)
      16             : #endif
      17             : 
      18             : #define __pfn_to_page(pfn)      (mem_map + ((pfn) - ARCH_PFN_OFFSET))
      19             : #define __page_to_pfn(page)     ((unsigned long)((page) - mem_map) + \
      20             :                                  ARCH_PFN_OFFSET)
      21             : 
      22             : #ifndef pfn_valid
      23             : static inline int pfn_valid(unsigned long pfn)
      24             : {
      25             :         /* avoid <linux/mm.h> include hell */
      26             :         extern unsigned long max_mapnr;
      27       59152 :         unsigned long pfn_offset = ARCH_PFN_OFFSET;
      28             : 
      29       58888 :         return pfn >= pfn_offset && (pfn - pfn_offset) < max_mapnr;
      30             : }
      31             : #define pfn_valid pfn_valid
      32             : #endif
      33             : 
      34             : #elif defined(CONFIG_SPARSEMEM_VMEMMAP)
      35             : 
      36             : /* memmap is virtually contiguous.  */
      37             : #define __pfn_to_page(pfn)      (vmemmap + (pfn))
      38             : #define __page_to_pfn(page)     (unsigned long)((page) - vmemmap)
      39             : 
      40             : #elif defined(CONFIG_SPARSEMEM)
      41             : /*
      42             :  * Note: section's mem_map is encoded to reflect its start_pfn.
      43             :  * section[i].section_mem_map == mem_map's address - start_pfn;
      44             :  */
      45             : #define __page_to_pfn(pg)                                       \
      46             : ({      const struct page *__pg = (pg);                         \
      47             :         int __sec = page_to_section(__pg);                      \
      48             :         (unsigned long)(__pg - __section_mem_map_addr(__nr_to_section(__sec))); \
      49             : })
      50             : 
      51             : #define __pfn_to_page(pfn)                              \
      52             : ({      unsigned long __pfn = (pfn);                    \
      53             :         struct mem_section *__sec = __pfn_to_section(__pfn);    \
      54             :         __section_mem_map_addr(__sec) + __pfn;          \
      55             : })
      56             : #endif /* CONFIG_FLATMEM/SPARSEMEM */
      57             : 
      58             : /*
      59             :  * Convert a physical address to a Page Frame Number and back
      60             :  */
      61             : #define __phys_to_pfn(paddr)    PHYS_PFN(paddr)
      62             : #define __pfn_to_phys(pfn)      PFN_PHYS(pfn)
      63             : 
      64             : #define page_to_pfn __page_to_pfn
      65             : #define pfn_to_page __pfn_to_page
      66             : 
      67             : #endif /* __ASSEMBLY__ */
      68             : 
      69             : #endif