[S390] noexec protection

[linux-2.6-omap-h63xx.git] / include / asm-s390 / pgalloc.h

diff --git a/include/asm-s390/pgalloc.h b/include/asm-s390/pgalloc.h
index 0707a7e2fc16dacb2fadc435dac8d50b2985a40a..56c8a6c80e2e18183b6bc4c11c0b53771bcee9f5 100644 (file)
--- a/include/asm-s390/pgalloc.h
+++ b/include/asm-s390/pgalloc.h
@@ -47,6 +47,17 @@ static inline pgd_t *pgd_alloc(struct mm_struct *mm)
 
        if (!pgd)
                return NULL;
+       if (s390_noexec) {
+               pgd_t *shadow_pgd = (pgd_t *)
+                       __get_free_pages(GFP_KERNEL, PGD_ALLOC_ORDER);
+               struct page *page = virt_to_page(pgd);
+
+               if (!shadow_pgd) {
+                       free_pages((unsigned long) pgd, PGD_ALLOC_ORDER);
+                       return NULL;
+               }
+               page->lru.next = (void *) shadow_pgd;
+       }
        for (i = 0; i < PTRS_PER_PGD; i++)
 #ifndef __s390x__
                pmd_clear(pmd_offset(pgd + i, i*PGDIR_SIZE));
@@ -58,6 +69,10 @@ static inline pgd_t *pgd_alloc(struct mm_struct *mm)
 
 static inline void pgd_free(pgd_t *pgd)
 {
+       pgd_t *shadow_pgd = get_shadow_pgd(pgd);
+
+       if (shadow_pgd)
+               free_pages((unsigned long) shadow_pgd, PGD_ALLOC_ORDER);
        free_pages((unsigned long) pgd, PGD_ALLOC_ORDER);
 }
 
@@ -71,6 +86,7 @@ static inline void pgd_free(pgd_t *pgd)
 #define pmd_free(x)                     do { } while (0)
 #define __pmd_free_tlb(tlb,x)          do { } while (0)
 #define pgd_populate(mm, pmd, pte)      BUG()
+#define pgd_populate_kernel(mm, pmd, pte)      BUG()
 #else /* __s390x__ */
 static inline pmd_t * pmd_alloc_one(struct mm_struct *mm, unsigned long vmaddr)
 {
@@ -79,6 +95,17 @@ static inline pmd_t * pmd_alloc_one(struct mm_struct *mm, unsigned long vmaddr)
 
        if (!pmd)
                return NULL;
+       if (s390_noexec) {
+               pmd_t *shadow_pmd = (pmd_t *)
+                       __get_free_pages(GFP_KERNEL, PMD_ALLOC_ORDER);
+               struct page *page = virt_to_page(pmd);
+
+               if (!shadow_pmd) {
+                       free_pages((unsigned long) pmd, PMD_ALLOC_ORDER);
+                       return NULL;
+               }
+               page->lru.next = (void *) shadow_pmd;
+       }
        for (i=0; i < PTRS_PER_PMD; i++)
                pmd_clear(pmd + i);
        return pmd;
@@ -86,6 +113,10 @@ static inline pmd_t * pmd_alloc_one(struct mm_struct *mm, unsigned long vmaddr)
 
 static inline void pmd_free (pmd_t *pmd)
 {
+       pmd_t *shadow_pmd = get_shadow_pmd(pmd);
+
+       if (shadow_pmd)
+               free_pages((unsigned long) shadow_pmd, PMD_ALLOC_ORDER);
        free_pages((unsigned long) pmd, PMD_ALLOC_ORDER);
 }
 
@@ -95,11 +126,22 @@ static inline void pmd_free (pmd_t *pmd)
                pmd_free(pmd);                  \
         } while (0)
 
-static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, pmd_t *pmd)
+static inline void
+pgd_populate_kernel(struct mm_struct *mm, pgd_t *pgd, pmd_t *pmd)
 {
        pgd_val(*pgd) = _PGD_ENTRY | __pa(pmd);
 }
 
+static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, pmd_t *pmd)
+{
+       pgd_t *shadow_pgd = get_shadow_pgd(pgd);
+       pmd_t *shadow_pmd = get_shadow_pmd(pmd);
+
+       if (shadow_pgd && shadow_pmd)
+               pgd_populate_kernel(mm, shadow_pgd, shadow_pmd);
+       pgd_populate_kernel(mm, pgd, pmd);
+}
+
 #endif /* __s390x__ */
 
 static inline void 
@@ -119,7 +161,13 @@ pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmd, pte_t *pte)
 static inline void
 pmd_populate(struct mm_struct *mm, pmd_t *pmd, struct page *page)
 {
-       pmd_populate_kernel(mm, pmd, (pte_t *)page_to_phys(page));
+       pte_t *pte = (pte_t *)page_to_phys(page);
+       pmd_t *shadow_pmd = get_shadow_pmd(pmd);
+       pte_t *shadow_pte = get_shadow_pte(pte);
+
+       pmd_populate_kernel(mm, pmd, pte);
+       if (shadow_pmd && shadow_pte)
+               pmd_populate_kernel(mm, shadow_pmd, shadow_pte);
 }
 
 /*
@@ -133,6 +181,17 @@ pte_alloc_one_kernel(struct mm_struct *mm, unsigned long vmaddr)
 
        if (!pte)
                return NULL;
+       if (s390_noexec) {
+               pte_t *shadow_pte = (pte_t *)
+                       __get_free_page(GFP_KERNEL|__GFP_REPEAT);
+               struct page *page = virt_to_page(pte);
+
+               if (!shadow_pte) {
+                       free_page((unsigned long) pte);
+                       return NULL;
+               }
+               page->lru.next = (void *) shadow_pte;
+       }
        for (i=0; i < PTRS_PER_PTE; i++) {
                pte_clear(mm, vmaddr, pte + i);
                vmaddr += PAGE_SIZE;
@@ -151,14 +210,30 @@ pte_alloc_one(struct mm_struct *mm, unsigned long vmaddr)
 
 static inline void pte_free_kernel(pte_t *pte)
 {
-        free_page((unsigned long) pte);
+       pte_t *shadow_pte = get_shadow_pte(pte);
+
+       if (shadow_pte)
+               free_page((unsigned long) shadow_pte);
+       free_page((unsigned long) pte);
 }
 
 static inline void pte_free(struct page *pte)
 {
-        __free_page(pte);
+       struct page *shadow_page = get_shadow_page(pte);
+
+       if (shadow_page)
+               __free_page(shadow_page);
+       __free_page(pte);
 }
 
-#define __pte_free_tlb(tlb,pte) tlb_remove_page(tlb,pte)
+#define __pte_free_tlb(tlb, pte)                                       \
+({                                                                     \
+       struct mmu_gather *__tlb = (tlb);                               \
+       struct page *__pte = (pte);                                     \
+       struct page *shadow_page = get_shadow_page(__pte);              \
+       if (shadow_page)                                                \
+               tlb_remove_page(__tlb, shadow_page);                    \
+       tlb_remove_page(__tlb, __pte);                                  \
+})
 
 #endif /* _S390_PGALLOC_H */