hugetlb: introduce generic version of prepare_hugepage_range
[muen/linux.git] / arch / mips / include / asm / hugetlb.h
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 2008, 2009 Cavium Networks, Inc.
7  */
8
9 #ifndef __ASM_HUGETLB_H
10 #define __ASM_HUGETLB_H
11
12 #include <asm/page.h>
13
14 static inline int is_hugepage_only_range(struct mm_struct *mm,
15                                          unsigned long addr,
16                                          unsigned long len)
17 {
18         return 0;
19 }
20
21 #define __HAVE_ARCH_PREPARE_HUGEPAGE_RANGE
22 static inline int prepare_hugepage_range(struct file *file,
23                                          unsigned long addr,
24                                          unsigned long len)
25 {
26         unsigned long task_size = STACK_TOP;
27         struct hstate *h = hstate_file(file);
28
29         if (len & ~huge_page_mask(h))
30                 return -EINVAL;
31         if (addr & ~huge_page_mask(h))
32                 return -EINVAL;
33         if (len > task_size)
34                 return -ENOMEM;
35         if (task_size - len < addr)
36                 return -EINVAL;
37         return 0;
38 }
39
40 #define __HAVE_ARCH_HUGE_PTEP_GET_AND_CLEAR
41 static inline pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
42                                             unsigned long addr, pte_t *ptep)
43 {
44         pte_t clear;
45         pte_t pte = *ptep;
46
47         pte_val(clear) = (unsigned long)invalid_pte_table;
48         set_pte_at(mm, addr, ptep, clear);
49         return pte;
50 }
51
52 #define __HAVE_ARCH_HUGE_PTEP_CLEAR_FLUSH
53 static inline void huge_ptep_clear_flush(struct vm_area_struct *vma,
54                                          unsigned long addr, pte_t *ptep)
55 {
56         flush_tlb_page(vma, addr & huge_page_mask(hstate_vma(vma)));
57 }
58
59 #define __HAVE_ARCH_HUGE_PTE_NONE
60 static inline int huge_pte_none(pte_t pte)
61 {
62         unsigned long val = pte_val(pte) & ~_PAGE_GLOBAL;
63         return !val || (val == (unsigned long)invalid_pte_table);
64 }
65
66 static inline void huge_ptep_set_wrprotect(struct mm_struct *mm,
67                                            unsigned long addr, pte_t *ptep)
68 {
69         ptep_set_wrprotect(mm, addr, ptep);
70 }
71
72 static inline int huge_ptep_set_access_flags(struct vm_area_struct *vma,
73                                              unsigned long addr,
74                                              pte_t *ptep, pte_t pte,
75                                              int dirty)
76 {
77         int changed = !pte_same(*ptep, pte);
78
79         if (changed) {
80                 set_pte_at(vma->vm_mm, addr, ptep, pte);
81                 /*
82                  * There could be some standard sized pages in there,
83                  * get them all.
84                  */
85                 flush_tlb_range(vma, addr, addr + HPAGE_SIZE);
86         }
87         return changed;
88 }
89
90 static inline pte_t huge_ptep_get(pte_t *ptep)
91 {
92         return *ptep;
93 }
94
95 static inline void arch_clear_hugepage_flags(struct page *page)
96 {
97 }
98
99 #include <asm-generic/hugetlb.h>
100
101 #endif /* __ASM_HUGETLB_H */