projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 305b1523 JG |
1 | /* |
| 2 | * Copyright IBM Corp. 2011 | |
| 3 | * Author(s): Jan Glauber <jang@linux.vnet.ibm.com> | |
| 4 | */ | |
| 5 | #include <linux/module.h> | |
| 6 | #include <linux/mm.h> | |
| 7 | #include <linux/hugetlb.h> | |
| 638ad34a | 8 | #include <asm/cacheflush.h> |
| 305b1523 JG |
9 | #include <asm/pgtable.h> |
| 10 | ||
| 5b1ba9e3 HC |
11 | static pte_t *walk_page_table(unsigned long addr) |
| 12 | { | |
| 13 | pgd_t *pgdp; | |
| 14 | pud_t *pudp; | |
| 15 | pmd_t *pmdp; | |
| 16 | pte_t *ptep; | |
| 17 | ||
| 18 | pgdp = pgd_offset_k(addr); | |
| 19 | if (pgd_none(*pgdp)) | |
| 20 | return NULL; | |
| 21 | pudp = pud_offset(pgdp, addr); | |
| 22 | if (pud_none(*pudp)) | |
| 23 | return NULL; | |
| 24 | pmdp = pmd_offset(pudp, addr); | |
| 25 | if (pmd_none(*pmdp) || pmd_large(*pmdp)) | |
| 26 | return NULL; | |
| 27 | ptep = pte_offset_kernel(pmdp, addr); | |
| 28 | if (pte_none(*ptep)) | |
| 29 | return NULL; | |
| 30 | return ptep; | |
| 31 | } | |
| 32 | ||
| 305b1523 JG |
33 | static void change_page_attr(unsigned long addr, int numpages, |
| 34 | pte_t (*set) (pte_t)) | |
| 35 | { | |
| 36 | pte_t *ptep, pte; | |
| 305b1523 JG |
37 | int i; |
| 38 | ||
| 39 | for (i = 0; i < numpages; i++) { | |
| 5b1ba9e3 HC |
40 | ptep = walk_page_table(addr); |
| 41 | if (WARN_ON_ONCE(!ptep)) | |
| 42 | break; | |
| 305b1523 JG |
43 | pte = *ptep; |
| 44 | pte = set(pte); | |
| b2fa47e6 | 45 | __ptep_ipte(addr, ptep); |
| 305b1523 | 46 | *ptep = pte; |
| e4c031b4 | 47 | addr += PAGE_SIZE; |
| 305b1523 JG |
48 | } |
| 49 | } | |
| 50 | ||
| 51 | int set_memory_ro(unsigned long addr, int numpages) | |
| 52 | { | |
| 53 | change_page_attr(addr, numpages, pte_wrprotect); | |
| 54 | return 0; | |
| 55 | } | |
| 305b1523 JG |
56 | |
| 57 | int set_memory_rw(unsigned long addr, int numpages) | |
| 58 | { | |
| 59 | change_page_attr(addr, numpages, pte_mkwrite); | |
| 60 | return 0; | |
| 61 | } | |
| 305b1523 JG |
62 | |
| 63 | /* not possible */ | |
| 64 | int set_memory_nx(unsigned long addr, int numpages) | |
| 65 | { | |
| 66 | return 0; | |
| 67 | } | |
| 448694a1 JG |
68 | |
| 69 | int set_memory_x(unsigned long addr, int numpages) | |
| 70 | { | |
| 71 | return 0; | |
| 72 | } |