diff options
Diffstat (limited to 'arch/s390/mm/init.c')
| -rw-r--r-- | arch/s390/mm/init.c | 35 |
1 files changed, 21 insertions, 14 deletions
diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c index 81dce185f83..eb6ebfef134 100644 --- a/arch/s390/mm/init.c +++ b/arch/s390/mm/init.c @@ -23,6 +23,7 @@ #include <linux/init.h> #include <linux/pagemap.h> #include <linux/bootmem.h> +#include <linux/pfn.h> #include <asm/processor.h> #include <asm/system.h> @@ -33,6 +34,7 @@ #include <asm/lowcore.h> #include <asm/tlb.h> #include <asm/tlbflush.h> +#include <asm/sections.h> DEFINE_PER_CPU(struct mmu_gather, mmu_gathers); @@ -89,17 +91,6 @@ void show_mem(void) printk("%d pages swap cached\n",cached); } -/* References to section boundaries */ - -extern unsigned long _text; -extern unsigned long _etext; -extern unsigned long _edata; -extern unsigned long __bss_start; -extern unsigned long _end; - -extern unsigned long __init_begin; -extern unsigned long __init_end; - extern unsigned long __initdata zholes_size[]; /* * paging_init() sets up the page tables @@ -116,6 +107,10 @@ void __init paging_init(void) unsigned long pfn = 0; unsigned long pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) | _KERNSEG_TABLE; static const int ssm_mask = 0x04000000L; + unsigned long ro_start_pfn, ro_end_pfn; + + ro_start_pfn = PFN_DOWN((unsigned long)&__start_rodata); + ro_end_pfn = PFN_UP((unsigned long)&__end_rodata); /* unmap whole virtual address space */ @@ -143,7 +138,10 @@ void __init paging_init(void) pg_dir++; for (tmp = 0 ; tmp < PTRS_PER_PTE ; tmp++,pg_table++) { - pte = pfn_pte(pfn, PAGE_KERNEL); + if (pfn >= ro_start_pfn && pfn < ro_end_pfn) + pte = pfn_pte(pfn, __pgprot(_PAGE_RO)); + else + pte = pfn_pte(pfn, PAGE_KERNEL); if (pfn >= max_low_pfn) pte_clear(&init_mm, 0, &pte); set_pte(pg_table, pte); @@ -175,6 +173,7 @@ void __init paging_init(void) } #else /* CONFIG_64BIT */ + void __init paging_init(void) { pgd_t * pg_dir; @@ -186,13 +185,15 @@ void __init paging_init(void) unsigned long pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) | _KERN_REGION_TABLE; static const int ssm_mask = 0x04000000L; - unsigned long zones_size[MAX_NR_ZONES]; unsigned long dma_pfn, high_pfn; + unsigned long ro_start_pfn, ro_end_pfn; memset(zones_size, 0, sizeof(zones_size)); dma_pfn = MAX_DMA_ADDRESS >> PAGE_SHIFT; high_pfn = max_low_pfn; + ro_start_pfn = PFN_DOWN((unsigned long)&__start_rodata); + ro_end_pfn = PFN_UP((unsigned long)&__end_rodata); if (dma_pfn > high_pfn) zones_size[ZONE_DMA] = high_pfn; @@ -231,7 +232,10 @@ void __init paging_init(void) pmd_populate_kernel(&init_mm, pm_dir, pt_dir); for (k = 0 ; k < PTRS_PER_PTE ; k++,pt_dir++) { - pte = pfn_pte(pfn, PAGE_KERNEL); + if (pfn >= ro_start_pfn && pfn < ro_end_pfn) + pte = pfn_pte(pfn, __pgprot(_PAGE_RO)); + else + pte = pfn_pte(pfn, PAGE_KERNEL); if (pfn >= max_low_pfn) { pte_clear(&init_mm, 0, &pte); continue; @@ -282,6 +286,9 @@ void __init mem_init(void) reservedpages << (PAGE_SHIFT-10), datasize >>10, initsize >> 10); + printk("Write protected kernel read-only data: %#lx - %#lx\n", + (unsigned long)&__start_rodata, + PFN_ALIGN((unsigned long)&__end_rodata) - 1); } void free_initmem(void) |