diff options
Diffstat (limited to 'arch/um/kernel/mem.c')
| -rw-r--r-- | arch/um/kernel/mem.c | 104 |
1 files changed, 80 insertions, 24 deletions
diff --git a/arch/um/kernel/mem.c b/arch/um/kernel/mem.c index 15295c3237a0..76bec7de81b5 100644 --- a/arch/um/kernel/mem.c +++ b/arch/um/kernel/mem.c @@ -6,18 +6,39 @@ #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> + +#ifdef CONFIG_KASAN +int kasan_um_is_ready; +void kasan_init(void) +{ + /* + * kasan_map_memory will map all of the required address space and + * the host machine will allocate physical memory as necessary. + */ + kasan_map_memory((void *)KASAN_SHADOW_START, KASAN_SHADOW_SIZE); + init_task.kasan_depth = 0; + kasan_um_is_ready = true; +} + +static void (*kasan_init_ptr)(void) +__section(".kasan_init") __used += kasan_init; +#endif /* allocated in paging_init, zeroed in mem_init, and unchanged thereafter */ unsigned long *empty_zero_page = NULL; @@ -30,14 +51,12 @@ 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) { /* clear the zero-page */ memset(empty_zero_page, 0, PAGE_SIZE); @@ -49,14 +68,16 @@ void __init mem_init(void) 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; +} + +void __init mem_init(void) +{ kmalloc_ok = 1; } +#if IS_ENABLED(CONFIG_ARCH_REUSE_HOST_VSYSCALL_AREA) /* * Create a page table and place a pointer to it in a middle page * directory entry. @@ -78,7 +99,7 @@ static void __init one_page_table_init(pmd_t *pmd) static void __init one_md_table_init(pud_t *pud) { -#ifdef CONFIG_3_LEVEL_PGTABLES +#if CONFIG_PGTABLE_LEVELS > 2 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", @@ -89,6 +110,19 @@ static void __init one_md_table_init(pud_t *pud) #endif } +static void __init one_ud_table_init(p4d_t *p4d) +{ +#if CONFIG_PGTABLE_LEVELS > 3 + pud_t *pud_table = (pud_t *) memblock_alloc_low(PAGE_SIZE, PAGE_SIZE); + if (!pud_table) + panic("%s: Failed to allocate %lu bytes align=%lx\n", + __func__, PAGE_SIZE, PAGE_SIZE); + + set_p4d(p4d, __p4d(_KERNPG_TABLE + (unsigned long) __pa(pud_table))); + BUG_ON(pud_table != pud_offset(p4d, 0)); +#endif +} + static void __init fixrange_init(unsigned long start, unsigned long end, pgd_t *pgd_base) { @@ -106,6 +140,8 @@ static void __init fixrange_init(unsigned long start, unsigned long end, for ( ; (i < PTRS_PER_PGD) && (vaddr < end); pgd++, i++) { p4d = p4d_offset(pgd, vaddr); + if (p4d_none(*p4d)) + one_ud_table_init(p4d); pud = pud_offset(p4d, vaddr); if (pud_none(*pud)) one_md_table_init(pud); @@ -120,7 +156,6 @@ static void __init fixrange_init(unsigned long start, unsigned long end, static void __init fixaddr_user_init( void) { -#ifdef CONFIG_ARCH_REUSE_HOST_VSYSCALL_AREA long size = FIXADDR_USER_END - FIXADDR_USER_START; pte_t *pte; phys_t p; @@ -142,13 +177,12 @@ static void __init fixaddr_user_init( void) pte = virt_to_kpte(vaddr); pte_set_val(*pte, p, PAGE_READONLY); } -#endif } +#endif 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); @@ -159,14 +193,9 @@ void __init paging_init(void) max_zone_pfn[ZONE_NORMAL] = end_iomem >> 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); - +#if IS_ENABLED(CONFIG_ARCH_REUSE_HOST_VSYSCALL_AREA) fixaddr_user_init(); +#endif } /* @@ -182,14 +211,13 @@ 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; } @@ -197,3 +225,31 @@ void *uml_kmalloc(int size, int flags) { return kmalloc(size, flags); } + +static const pgprot_t protection_map[16] = { + [VM_NONE] = PAGE_NONE, + [VM_READ] = PAGE_READONLY, + [VM_WRITE] = PAGE_COPY, + [VM_WRITE | VM_READ] = PAGE_COPY, + [VM_EXEC] = PAGE_READONLY, + [VM_EXEC | VM_READ] = PAGE_READONLY, + [VM_EXEC | VM_WRITE] = PAGE_COPY, + [VM_EXEC | VM_WRITE | VM_READ] = PAGE_COPY, + [VM_SHARED] = PAGE_NONE, + [VM_SHARED | VM_READ] = PAGE_READONLY, + [VM_SHARED | VM_WRITE] = PAGE_SHARED, + [VM_SHARED | VM_WRITE | VM_READ] = PAGE_SHARED, + [VM_SHARED | VM_EXEC] = PAGE_READONLY, + [VM_SHARED | VM_EXEC | VM_READ] = PAGE_READONLY, + [VM_SHARED | VM_EXEC | VM_WRITE] = PAGE_SHARED, + [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); +} |