Linux Kernel  3.7.1
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
pgtable-nopmd.h
Go to the documentation of this file.
1 #ifndef _PGTABLE_NOPMD_H
2 #define _PGTABLE_NOPMD_H
3 
4 #ifndef __ASSEMBLY__
5 
7 
8 struct mm_struct;
9 
10 #define __PAGETABLE_PMD_FOLDED
11 
12 /*
13  * Having the pmd type consist of a pud gets the size right, and allows
14  * us to conceptually access the pud entry that this pmd is folded into
15  * without casting.
16  */
17 typedef struct { pud_t pud; } pmd_t;
18 
19 #define PMD_SHIFT PUD_SHIFT
20 #define PTRS_PER_PMD 1
21 #define PMD_SIZE (1UL << PMD_SHIFT)
22 #define PMD_MASK (~(PMD_SIZE-1))
23 
24 /*
25  * The "pud_xxx()" functions here are trivial for a folded two-level
26  * setup: the pmd is never bad, and a pmd always exists (as it's folded
27  * into the pud entry)
28  */
29 static inline int pud_none(pud_t pud) { return 0; }
30 static inline int pud_bad(pud_t pud) { return 0; }
31 static inline int pud_present(pud_t pud) { return 1; }
32 static inline void pud_clear(pud_t *pud) { }
33 #define pmd_ERROR(pmd) (pud_ERROR((pmd).pud))
34 
35 #define pud_populate(mm, pmd, pte) do { } while (0)
36 
37 /*
38  * (pmds are folded into puds so this doesn't get actually called,
39  * but the define is needed for a generic inline function.)
40  */
41 #define set_pud(pudptr, pudval) set_pmd((pmd_t *)(pudptr), (pmd_t) { pudval })
42 
43 static inline pmd_t * pmd_offset(pud_t * pud, unsigned long address)
44 {
45  return (pmd_t *)pud;
46 }
47 
48 #define pmd_val(x) (pud_val((x).pud))
49 #define __pmd(x) ((pmd_t) { __pud(x) } )
50 
51 #define pud_page(pud) (pmd_page((pmd_t){ pud }))
52 #define pud_page_vaddr(pud) (pmd_page_vaddr((pmd_t){ pud }))
53 
54 /*
55  * allocating and freeing a pmd is trivial: the 1-entry pmd is
56  * inside the pud, so has no extra memory associated with it.
57  */
58 #define pmd_alloc_one(mm, address) NULL
59 static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
60 {
61 }
62 #define __pmd_free_tlb(tlb, x, a) do { } while (0)
63 
64 #undef pmd_addr_end
65 #define pmd_addr_end(addr, end) (end)
66 
67 #endif /* __ASSEMBLY__ */
68 
69 #endif /* _PGTABLE_NOPMD_H */