diff options
| -rw-r--r-- | arch/arm/include/asm/pgtable-nommu.h | 6 | ||||
| -rw-r--r-- | arch/arm/include/asm/pgtable.h | 16 | ||||
| -rw-r--r-- | arch/arm/mm/nommu.c | 19 |
3 files changed, 28 insertions, 13 deletions
diff --git a/arch/arm/include/asm/pgtable-nommu.h b/arch/arm/include/asm/pgtable-nommu.h index 010fa1a35a68..e8ac2f95fb37 100644 --- a/arch/arm/include/asm/pgtable-nommu.h +++ b/arch/arm/include/asm/pgtable-nommu.h @@ -52,12 +52,6 @@ typedef pte_t *pte_addr_t; /* - * ZERO_PAGE is a global shared page that is always zero: used - * for zero-mapped memory areas etc.. - */ -#define ZERO_PAGE(vaddr) (virt_to_page(0)) - -/* * Mark the prot value as uncacheable and unbufferable. */ #define pgprot_noncached(prot) (prot) diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h index 3ae120cd1715..ecfd6e7e128f 100644 --- a/arch/arm/include/asm/pgtable.h +++ b/arch/arm/include/asm/pgtable.h @@ -10,6 +10,15 @@ #include <linux/const.h> #include <asm/proc-fns.h> +#ifndef __ASSEMBLY__ +/* + * ZERO_PAGE is a global shared page that is always zero: used + * for zero-mapped memory areas etc.. + */ +extern struct page *empty_zero_page; +#define ZERO_PAGE(vaddr) (empty_zero_page) +#endif + #ifndef CONFIG_MMU #include <asm-generic/4level-fixup.h> @@ -166,13 +175,6 @@ extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, #define __S111 __PAGE_SHARED_EXEC #ifndef __ASSEMBLY__ -/* - * ZERO_PAGE is a global shared page that is always zero: used - * for zero-mapped memory areas etc.. - */ -extern struct page *empty_zero_page; -#define ZERO_PAGE(vaddr) (empty_zero_page) - extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; diff --git a/arch/arm/mm/nommu.c b/arch/arm/mm/nommu.c index 24ecf8d30a1e..a3ad8a1b0e07 100644 --- a/arch/arm/mm/nommu.c +++ b/arch/arm/mm/nommu.c @@ -26,6 +26,13 @@ unsigned long vectors_base; +/* + * empty_zero_page is a special page that is used for + * zero-initialized data and COW. + */ +struct page *empty_zero_page; +EXPORT_SYMBOL(empty_zero_page); + #ifdef CONFIG_ARM_MPU struct mpu_rgn_info mpu_rgn_info; #endif @@ -148,9 +155,21 @@ void __init adjust_lowmem_bounds(void) */ void __init paging_init(const struct machine_desc *mdesc) { + void *zero_page; + early_trap_init((void *)vectors_base); mpu_setup(); + + /* allocate the zero page. */ + zero_page = memblock_alloc(PAGE_SIZE, PAGE_SIZE); + if (!zero_page) + panic("%s: Failed to allocate %lu bytes align=0x%lx\n", + __func__, PAGE_SIZE, PAGE_SIZE); + bootmem_init(); + + empty_zero_page = virt_to_page(zero_page); + flush_dcache_page(empty_zero_page); } /* |