include/asm-generic/page.h

0001 /* SPDX-License-Identifier: GPL-2.0 */
0002 #ifndef __ASM_GENERIC_PAGE_H
0003 #define __ASM_GENERIC_PAGE_H
0004 /*
0005  * Generic page.h implementation, for NOMMU architectures.
0006  * This provides the dummy definitions for the memory management.
0007  */
0008
0009 #ifdef CONFIG_MMU
0010 #error need to provide a real asm/page.h
0011 #endif
0012
0013
0014 /* PAGE_SHIFT determines the page size */
0015
0016 #define PAGE_SHIFT  12
0017 #ifdef __ASSEMBLY__
0018 #define PAGE_SIZE   (1 << PAGE_SHIFT)
0019 #else
0020 #define PAGE_SIZE   (1UL << PAGE_SHIFT)
0021 #endif
0022 #define PAGE_MASK   (~(PAGE_SIZE-1))
0023
0024 #include <asm/setup.h>
0025
0026 #ifndef __ASSEMBLY__
0027
0028 #define clear_page(page)    memset((page), 0, PAGE_SIZE)
0029 #define copy_page(to,from)  memcpy((to), (from), PAGE_SIZE)
0030
0031 #define clear_user_page(page, vaddr, pg)    clear_page(page)
0032 #define copy_user_page(to, from, vaddr, pg) copy_page(to, from)
0033
0034 /*
0035  * These are used to make use of C type-checking..
0036  */
0037 typedef struct {
0038     unsigned long pte;
0039 } pte_t;
0040 typedef struct {
0041     unsigned long pmd[16];
0042 } pmd_t;
0043 typedef struct {
0044     unsigned long pgd;
0045 } pgd_t;
0046 typedef struct {
0047     unsigned long pgprot;
0048 } pgprot_t;
0049 typedef struct page *pgtable_t;
0050
0051 #define pte_val(x)  ((x).pte)
0052 #define pmd_val(x)  ((&x)->pmd[0])
0053 #define pgd_val(x)  ((x).pgd)
0054 #define pgprot_val(x)   ((x).pgprot)
0055
0056 #define __pte(x)    ((pte_t) { (x) } )
0057 #define __pmd(x)    ((pmd_t) { (x) } )
0058 #define __pgd(x)    ((pgd_t) { (x) } )
0059 #define __pgprot(x) ((pgprot_t) { (x) } )
0060
0061 extern unsigned long memory_start;
0062 extern unsigned long memory_end;
0063
0064 #endif /* !__ASSEMBLY__ */
0065
0066 #define PAGE_OFFSET     (0)
0067
0068 #ifndef ARCH_PFN_OFFSET
0069 #define ARCH_PFN_OFFSET     (PAGE_OFFSET >> PAGE_SHIFT)
0070 #endif
0071
0072 #ifndef __ASSEMBLY__
0073
0074 #define __va(x) ((void *)((unsigned long) (x)))
0075 #define __pa(x) ((unsigned long) (x))
0076
0077 #define virt_to_pfn(kaddr)  (__pa(kaddr) >> PAGE_SHIFT)
0078 #define pfn_to_virt(pfn)    __va((pfn) << PAGE_SHIFT)
0079
0080 #define virt_to_page(addr)  pfn_to_page(virt_to_pfn(addr))
0081 #define page_to_virt(page)  pfn_to_virt(page_to_pfn(page))
0082
0083 #ifndef page_to_phys
0084 #define page_to_phys(page)      ((dma_addr_t)page_to_pfn(page) << PAGE_SHIFT)
0085 #endif
0086
0087 #define pfn_valid(pfn)      ((pfn) >= ARCH_PFN_OFFSET && ((pfn) - ARCH_PFN_OFFSET) < max_mapnr)
0088
0089 #define virt_addr_valid(kaddr)  (((void *)(kaddr) >= (void *)PAGE_OFFSET) && \
0090                 ((void *)(kaddr) < (void *)memory_end))
0091
0092 #endif /* __ASSEMBLY__ */
0093
0094 #include <asm-generic/memory_model.h>
0095 #include <asm-generic/getorder.h>
0096
0097 #endif /* __ASM_GENERIC_PAGE_H */