diff options
Diffstat (limited to 'arch/um/kernel/mem.c')
| -rw-r--r-- | arch/um/kernel/mem.c | 145 |
1 files changed, 31 insertions, 114 deletions
diff --git a/arch/um/kernel/mem.c b/arch/um/kernel/mem.c index 38d5a71a579b..39c4a7e21c6f 100644 --- a/arch/um/kernel/mem.c +++ b/arch/um/kernel/mem.c @@ -6,23 +6,25 @@ #include <linux/stddef.h> #include <linux/module.h> #include <linux/memblock.h> -#include <linux/highmem.h> #include <linux/mm.h> #include <linux/swap.h> #include <linux/slab.h> -#include <asm/fixmap.h> +#include <linux/init.h> +#include <asm/sections.h> #include <asm/page.h> +#include <asm/pgalloc.h> #include <as-layout.h> #include <init.h> #include <kern.h> #include <kern_util.h> #include <mem_user.h> #include <os.h> +#include <um_malloc.h> #include <linux/sched/task.h> +#include <linux/kasan.h> #ifdef CONFIG_KASAN -int kasan_um_is_ready; -void kasan_init(void) +void __init kasan_init(void) { /* * kasan_map_memory will map all of the required address space and @@ -30,7 +32,11 @@ void kasan_init(void) */ kasan_map_memory((void *)KASAN_SHADOW_START, KASAN_SHADOW_SIZE); init_task.kasan_depth = 0; - kasan_um_is_ready = true; + /* + * Since kasan_init() is called before main(), + * KASAN is initialized but the enablement is deferred after + * jump_label_init(). See arch_mm_preinit(). + */ } static void (*kasan_init_ptr)(void) @@ -49,125 +55,38 @@ EXPORT_SYMBOL(empty_zero_page); pgd_t swapper_pg_dir[PTRS_PER_PGD]; /* Initialized at boot time, and readonly after that */ -unsigned long long highmem; -EXPORT_SYMBOL(highmem); int kmalloc_ok = 0; /* Used during early boot */ static unsigned long brk_end; -void __init mem_init(void) +void __init arch_mm_preinit(void) { + /* Safe to call after jump_label_init(). Enables KASAN. */ + kasan_init_generic(); + /* clear the zero-page */ memset(empty_zero_page, 0, PAGE_SIZE); /* Map in the area just after the brk now that kmalloc is about * to be turned on. */ - brk_end = (unsigned long) UML_ROUND_UP(sbrk(0)); + brk_end = PAGE_ALIGN((unsigned long) sbrk(0)); map_memory(brk_end, __pa(brk_end), uml_reserved - brk_end, 1, 1, 0); memblock_free((void *)brk_end, uml_reserved - brk_end); uml_reserved = brk_end; - - /* this will put all low memory onto the freelists */ - memblock_free_all(); - max_low_pfn = totalram_pages(); + min_low_pfn = PFN_UP(__pa(uml_reserved)); max_pfn = max_low_pfn; - kmalloc_ok = 1; -} - -/* - * Create a page table and place a pointer to it in a middle page - * directory entry. - */ -static void __init one_page_table_init(pmd_t *pmd) -{ - if (pmd_none(*pmd)) { - pte_t *pte = (pte_t *) memblock_alloc_low(PAGE_SIZE, - PAGE_SIZE); - if (!pte) - panic("%s: Failed to allocate %lu bytes align=%lx\n", - __func__, PAGE_SIZE, PAGE_SIZE); - - set_pmd(pmd, __pmd(_KERNPG_TABLE + - (unsigned long) __pa(pte))); - BUG_ON(pte != pte_offset_kernel(pmd, 0)); - } -} - -static void __init one_md_table_init(pud_t *pud) -{ -#ifdef CONFIG_3_LEVEL_PGTABLES - pmd_t *pmd_table = (pmd_t *) memblock_alloc_low(PAGE_SIZE, PAGE_SIZE); - if (!pmd_table) - panic("%s: Failed to allocate %lu bytes align=%lx\n", - __func__, PAGE_SIZE, PAGE_SIZE); - - set_pud(pud, __pud(_KERNPG_TABLE + (unsigned long) __pa(pmd_table))); - BUG_ON(pmd_table != pmd_offset(pud, 0)); -#endif } -static void __init fixrange_init(unsigned long start, unsigned long end, - pgd_t *pgd_base) -{ - pgd_t *pgd; - p4d_t *p4d; - pud_t *pud; - pmd_t *pmd; - int i, j; - unsigned long vaddr; - - vaddr = start; - i = pgd_index(vaddr); - j = pmd_index(vaddr); - pgd = pgd_base + i; - - for ( ; (i < PTRS_PER_PGD) && (vaddr < end); pgd++, i++) { - p4d = p4d_offset(pgd, vaddr); - pud = pud_offset(p4d, vaddr); - if (pud_none(*pud)) - one_md_table_init(pud); - pmd = pmd_offset(pud, vaddr); - for (; (j < PTRS_PER_PMD) && (vaddr < end); pmd++, j++) { - one_page_table_init(pmd); - vaddr += PMD_SIZE; - } - j = 0; - } -} - -static void __init fixaddr_user_init( void) +void __init mem_init(void) { -#ifdef CONFIG_ARCH_REUSE_HOST_VSYSCALL_AREA - long size = FIXADDR_USER_END - FIXADDR_USER_START; - pte_t *pte; - phys_t p; - unsigned long v, vaddr = FIXADDR_USER_START; - - if (!size) - return; - - fixrange_init( FIXADDR_USER_START, FIXADDR_USER_END, swapper_pg_dir); - v = (unsigned long) memblock_alloc_low(size, PAGE_SIZE); - if (!v) - panic("%s: Failed to allocate %lu bytes align=%lx\n", - __func__, size, PAGE_SIZE); - - memcpy((void *) v , (void *) FIXADDR_USER_START, size); - p = __pa(v); - for ( ; size > 0; size -= PAGE_SIZE, vaddr += PAGE_SIZE, - p += PAGE_SIZE) { - pte = virt_to_kpte(vaddr); - pte_set_val(*pte, p, PAGE_READONLY); - } -#endif + kmalloc_ok = 1; } void __init paging_init(void) { unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0 }; - unsigned long vaddr; empty_zero_page = (unsigned long *) memblock_alloc_low(PAGE_SIZE, PAGE_SIZE); @@ -175,17 +94,8 @@ void __init paging_init(void) panic("%s: Failed to allocate %lu bytes align=%lx\n", __func__, PAGE_SIZE, PAGE_SIZE); - max_zone_pfn[ZONE_NORMAL] = end_iomem >> PAGE_SHIFT; + max_zone_pfn[ZONE_NORMAL] = high_physmem >> PAGE_SHIFT; free_area_init(max_zone_pfn); - - /* - * Fixed mappings, only the page table structure has to be - * created - mappings will be set by set_fixmap(): - */ - vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK; - fixrange_init(vaddr, FIXADDR_TOP, swapper_pg_dir); - - fixaddr_user_init(); } /* @@ -201,14 +111,13 @@ void free_initmem(void) pgd_t *pgd_alloc(struct mm_struct *mm) { - pgd_t *pgd = (pgd_t *)__get_free_page(GFP_KERNEL); + pgd_t *pgd = __pgd_alloc(mm, 0); - if (pgd) { - memset(pgd, 0, USER_PTRS_PER_PGD * sizeof(pgd_t)); + if (pgd) memcpy(pgd + USER_PTRS_PER_PGD, swapper_pg_dir + USER_PTRS_PER_PGD, (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t)); - } + return pgd; } @@ -236,3 +145,11 @@ static const pgprot_t protection_map[16] = { [VM_SHARED | VM_EXEC | VM_WRITE | VM_READ] = PAGE_SHARED }; DECLARE_VM_GET_PAGE_PROT + +void mark_rodata_ro(void) +{ + unsigned long rodata_start = PFN_ALIGN(__start_rodata); + unsigned long rodata_end = PFN_ALIGN(__end_rodata); + + os_protect_memory((void *)rodata_start, rodata_end - rodata_start, 1, 0, 0); +} |