diff options
Diffstat (limited to 'arch/s390/mm')
| -rw-r--r-- | arch/s390/mm/Makefile | 1 | ||||
| -rw-r--r-- | arch/s390/mm/pageattr.c | 55 | ||||
| -rw-r--r-- | arch/s390/mm/pgtable.c | 3 |
3 files changed, 58 insertions, 1 deletions
diff --git a/arch/s390/mm/Makefile b/arch/s390/mm/Makefile index 6fbc6f3fbdf..d98fe9004a5 100644 --- a/arch/s390/mm/Makefile +++ b/arch/s390/mm/Makefile @@ -6,3 +6,4 @@ obj-y := init.o fault.o extmem.o mmap.o vmem.o pgtable.o maccess.o \ page-states.o gup.o obj-$(CONFIG_CMM) += cmm.o obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o +obj-$(CONFIG_DEBUG_SET_MODULE_RONX) += pageattr.o diff --git a/arch/s390/mm/pageattr.c b/arch/s390/mm/pageattr.c new file mode 100644 index 00000000000..122ffbd08ce --- /dev/null +++ b/arch/s390/mm/pageattr.c @@ -0,0 +1,55 @@ +/* + * Copyright IBM Corp. 2011 + * Author(s): Jan Glauber <jang@linux.vnet.ibm.com> + */ +#include <linux/module.h> +#include <linux/mm.h> +#include <linux/hugetlb.h> +#include <asm/pgtable.h> + +static void change_page_attr(unsigned long addr, int numpages, + pte_t (*set) (pte_t)) +{ + pte_t *ptep, pte; + pmd_t *pmdp; + pud_t *pudp; + pgd_t *pgdp; + int i; + + for (i = 0; i < numpages; i++) { + pgdp = pgd_offset(&init_mm, addr); + pudp = pud_offset(pgdp, addr); + pmdp = pmd_offset(pudp, addr); + if (pmd_huge(*pmdp)) { + WARN_ON_ONCE(1); + continue; + } + ptep = pte_offset_kernel(pmdp, addr + i * PAGE_SIZE); + + pte = *ptep; + pte = set(pte); + ptep_invalidate(&init_mm, addr + i * PAGE_SIZE, ptep); + *ptep = pte; + } +} + +int set_memory_ro(unsigned long addr, int numpages) +{ + change_page_attr(addr, numpages, pte_wrprotect); + return 0; +} +EXPORT_SYMBOL_GPL(set_memory_ro); + +int set_memory_rw(unsigned long addr, int numpages) +{ + change_page_attr(addr, numpages, pte_mkwrite); + return 0; +} +EXPORT_SYMBOL_GPL(set_memory_rw); + +/* not possible */ +int set_memory_nx(unsigned long addr, int numpages) +{ + return 0; +} +EXPORT_SYMBOL_GPL(set_memory_nx); diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c index 0c719c61972..e1850c28cd6 100644 --- a/arch/s390/mm/pgtable.c +++ b/arch/s390/mm/pgtable.c @@ -336,7 +336,8 @@ void page_table_free(struct mm_struct *mm, unsigned long *table) page->flags ^= bits; if (page->flags & FRAG_MASK) { /* Page now has some free pgtable fragments. */ - list_move(&page->lru, &mm->context.pgtable_list); + if (!list_empty(&page->lru)) + list_move(&page->lru, &mm->context.pgtable_list); page = NULL; } else /* All fragments of the 4K page have been freed. */ |