| /* |
| * Copyright IBM Corp. 2011 |
| * Author(s): Jan Glauber <jang@linux.vnet.ibm.com> |
| */ |
| #include <linux/hugetlb.h> |
| #include <linux/module.h> |
| #include <linux/mm.h> |
| #include <asm/cacheflush.h> |
| #include <asm/pgtable.h> |
| #include <asm/page.h> |
| |
| void storage_key_init_range(unsigned long start, unsigned long end) |
| { |
| unsigned long boundary, function, size; |
| |
| while (start < end) { |
| if (MACHINE_HAS_EDAT2) { |
| /* set storage keys for a 2GB frame */ |
| function = 0x22000 | PAGE_DEFAULT_KEY; |
| size = 1UL << 31; |
| boundary = (start + size) & ~(size - 1); |
| if (boundary <= end) { |
| do { |
| start = pfmf(function, start); |
| } while (start < boundary); |
| continue; |
| } |
| } |
| if (MACHINE_HAS_EDAT1) { |
| /* set storage keys for a 1MB frame */ |
| function = 0x21000 | PAGE_DEFAULT_KEY; |
| size = 1UL << 20; |
| boundary = (start + size) & ~(size - 1); |
| if (boundary <= end) { |
| do { |
| start = pfmf(function, start); |
| } while (start < boundary); |
| continue; |
| } |
| } |
| page_set_storage_key(start, PAGE_DEFAULT_KEY, 0); |
| start += PAGE_SIZE; |
| } |
| } |
| |
| static pte_t *walk_page_table(unsigned long addr) |
| { |
| pgd_t *pgdp; |
| pud_t *pudp; |
| pmd_t *pmdp; |
| pte_t *ptep; |
| |
| pgdp = pgd_offset_k(addr); |
| if (pgd_none(*pgdp)) |
| return NULL; |
| pudp = pud_offset(pgdp, addr); |
| if (pud_none(*pudp) || pud_large(*pudp)) |
| return NULL; |
| pmdp = pmd_offset(pudp, addr); |
| if (pmd_none(*pmdp) || pmd_large(*pmdp)) |
| return NULL; |
| ptep = pte_offset_kernel(pmdp, addr); |
| if (pte_none(*ptep)) |
| return NULL; |
| return ptep; |
| } |
| |
| static void change_page_attr(unsigned long addr, int numpages, |
| pte_t (*set) (pte_t)) |
| { |
| pte_t *ptep, pte; |
| int i; |
| |
| for (i = 0; i < numpages; i++) { |
| ptep = walk_page_table(addr); |
| if (WARN_ON_ONCE(!ptep)) |
| break; |
| pte = *ptep; |
| pte = set(pte); |
| __ptep_ipte(addr, ptep); |
| *ptep = pte; |
| addr += PAGE_SIZE; |
| } |
| } |
| |
| int set_memory_ro(unsigned long addr, int numpages) |
| { |
| change_page_attr(addr, numpages, pte_wrprotect); |
| return 0; |
| } |
| |
| int set_memory_rw(unsigned long addr, int numpages) |
| { |
| change_page_attr(addr, numpages, pte_mkwrite); |
| return 0; |
| } |
| |
| /* not possible */ |
| int set_memory_nx(unsigned long addr, int numpages) |
| { |
| return 0; |
| } |
| |
| int set_memory_x(unsigned long addr, int numpages) |
| { |
| return 0; |
| } |