804 lines
19 KiB
C
804 lines
19 KiB
C
/*
|
|
* linux/arch/arm/mm/init.c
|
|
*
|
|
* Copyright (C) 1995-2005 Russell King
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
#include <linux/kernel.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/swap.h>
|
|
#include <linux/init.h>
|
|
#include <linux/bootmem.h>
|
|
#include <linux/mman.h>
|
|
#include <linux/sched/signal.h>
|
|
#include <linux/sched/task.h>
|
|
#include <linux/export.h>
|
|
#include <linux/nodemask.h>
|
|
#include <linux/initrd.h>
|
|
#include <linux/of_fdt.h>
|
|
#include <linux/highmem.h>
|
|
#include <linux/gfp.h>
|
|
#include <linux/memblock.h>
|
|
#include <linux/dma-contiguous.h>
|
|
#include <linux/sizes.h>
|
|
#include <linux/stop_machine.h>
|
|
|
|
#include <asm/cp15.h>
|
|
#include <asm/mach-types.h>
|
|
#include <asm/memblock.h>
|
|
#include <asm/memory.h>
|
|
#include <asm/prom.h>
|
|
#include <asm/sections.h>
|
|
#include <asm/setup.h>
|
|
#include <asm/system_info.h>
|
|
#include <asm/tlb.h>
|
|
#include <asm/fixmap.h>
|
|
#include <asm/ptdump.h>
|
|
|
|
#include <asm/mach/arch.h>
|
|
#include <asm/mach/map.h>
|
|
|
|
#include "mm.h"
|
|
|
|
#ifdef CONFIG_CPU_CP15_MMU
|
|
unsigned long __init __clear_cr(unsigned long mask)
|
|
{
|
|
cr_alignment = cr_alignment & ~mask;
|
|
return cr_alignment;
|
|
}
|
|
#endif
|
|
|
|
static phys_addr_t phys_initrd_start __initdata = 0;
|
|
static unsigned long phys_initrd_size __initdata = 0;
|
|
|
|
static int __init early_initrd(char *p)
|
|
{
|
|
phys_addr_t start;
|
|
unsigned long size;
|
|
char *endp;
|
|
|
|
start = memparse(p, &endp);
|
|
if (*endp == ',') {
|
|
size = memparse(endp + 1, NULL);
|
|
|
|
phys_initrd_start = start;
|
|
phys_initrd_size = size;
|
|
}
|
|
return 0;
|
|
}
|
|
early_param("initrd", early_initrd);
|
|
|
|
static int __init parse_tag_initrd(const struct tag *tag)
|
|
{
|
|
pr_warn("ATAG_INITRD is deprecated; "
|
|
"please update your bootloader.\n");
|
|
phys_initrd_start = __virt_to_phys(tag->u.initrd.start);
|
|
phys_initrd_size = tag->u.initrd.size;
|
|
return 0;
|
|
}
|
|
|
|
__tagtable(ATAG_INITRD, parse_tag_initrd);
|
|
|
|
static int __init parse_tag_initrd2(const struct tag *tag)
|
|
{
|
|
phys_initrd_start = tag->u.initrd.start;
|
|
phys_initrd_size = tag->u.initrd.size;
|
|
return 0;
|
|
}
|
|
|
|
__tagtable(ATAG_INITRD2, parse_tag_initrd2);
|
|
|
|
static void __init find_limits(unsigned long *min, unsigned long *max_low,
|
|
unsigned long *max_high)
|
|
{
|
|
*max_low = PFN_DOWN(memblock_get_current_limit());
|
|
*min = PFN_UP(memblock_start_of_DRAM());
|
|
*max_high = PFN_DOWN(memblock_end_of_DRAM());
|
|
}
|
|
|
|
#ifdef CONFIG_ZONE_DMA
|
|
|
|
phys_addr_t arm_dma_zone_size __read_mostly;
|
|
EXPORT_SYMBOL(arm_dma_zone_size);
|
|
|
|
/*
|
|
* The DMA mask corresponding to the maximum bus address allocatable
|
|
* using GFP_DMA. The default here places no restriction on DMA
|
|
* allocations. This must be the smallest DMA mask in the system,
|
|
* so a successful GFP_DMA allocation will always satisfy this.
|
|
*/
|
|
phys_addr_t arm_dma_limit;
|
|
unsigned long arm_dma_pfn_limit;
|
|
|
|
static void __init arm_adjust_dma_zone(unsigned long *size, unsigned long *hole,
|
|
unsigned long dma_size)
|
|
{
|
|
if (size[0] <= dma_size)
|
|
return;
|
|
|
|
size[ZONE_NORMAL] = size[0] - dma_size;
|
|
size[ZONE_DMA] = dma_size;
|
|
hole[ZONE_NORMAL] = hole[0];
|
|
hole[ZONE_DMA] = 0;
|
|
}
|
|
#endif
|
|
|
|
void __init setup_dma_zone(const struct machine_desc *mdesc)
|
|
{
|
|
#ifdef CONFIG_ZONE_DMA
|
|
if (mdesc->dma_zone_size) {
|
|
arm_dma_zone_size = mdesc->dma_zone_size;
|
|
arm_dma_limit = PHYS_OFFSET + arm_dma_zone_size - 1;
|
|
} else
|
|
arm_dma_limit = 0xffffffff;
|
|
arm_dma_pfn_limit = arm_dma_limit >> PAGE_SHIFT;
|
|
#endif
|
|
}
|
|
|
|
static void __init zone_sizes_init(unsigned long min, unsigned long max_low,
|
|
unsigned long max_high)
|
|
{
|
|
unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
|
|
struct memblock_region *reg;
|
|
|
|
/*
|
|
* initialise the zones.
|
|
*/
|
|
memset(zone_size, 0, sizeof(zone_size));
|
|
|
|
/*
|
|
* The memory size has already been determined. If we need
|
|
* to do anything fancy with the allocation of this memory
|
|
* to the zones, now is the time to do it.
|
|
*/
|
|
zone_size[0] = max_low - min;
|
|
#ifdef CONFIG_HIGHMEM
|
|
zone_size[ZONE_HIGHMEM] = max_high - max_low;
|
|
#endif
|
|
|
|
/*
|
|
* Calculate the size of the holes.
|
|
* holes = node_size - sum(bank_sizes)
|
|
*/
|
|
memcpy(zhole_size, zone_size, sizeof(zhole_size));
|
|
for_each_memblock(memory, reg) {
|
|
unsigned long start = memblock_region_memory_base_pfn(reg);
|
|
unsigned long end = memblock_region_memory_end_pfn(reg);
|
|
|
|
if (start < max_low) {
|
|
unsigned long low_end = min(end, max_low);
|
|
zhole_size[0] -= low_end - start;
|
|
}
|
|
#ifdef CONFIG_HIGHMEM
|
|
if (end > max_low) {
|
|
unsigned long high_start = max(start, max_low);
|
|
zhole_size[ZONE_HIGHMEM] -= end - high_start;
|
|
}
|
|
#endif
|
|
}
|
|
|
|
#ifdef CONFIG_ZONE_DMA
|
|
/*
|
|
* Adjust the sizes according to any special requirements for
|
|
* this machine type.
|
|
*/
|
|
if (arm_dma_zone_size)
|
|
arm_adjust_dma_zone(zone_size, zhole_size,
|
|
arm_dma_zone_size >> PAGE_SHIFT);
|
|
#endif
|
|
|
|
free_area_init_node(0, zone_size, min, zhole_size);
|
|
}
|
|
|
|
#ifdef CONFIG_HAVE_ARCH_PFN_VALID
|
|
int pfn_valid(unsigned long pfn)
|
|
{
|
|
return memblock_is_map_memory(__pfn_to_phys(pfn));
|
|
}
|
|
EXPORT_SYMBOL(pfn_valid);
|
|
#endif
|
|
|
|
#ifndef CONFIG_SPARSEMEM
|
|
static void __init arm_memory_present(void)
|
|
{
|
|
}
|
|
#else
|
|
static void __init arm_memory_present(void)
|
|
{
|
|
struct memblock_region *reg;
|
|
|
|
for_each_memblock(memory, reg)
|
|
memory_present(0, memblock_region_memory_base_pfn(reg),
|
|
memblock_region_memory_end_pfn(reg));
|
|
}
|
|
#endif
|
|
|
|
static bool arm_memblock_steal_permitted = true;
|
|
|
|
phys_addr_t __init arm_memblock_steal(phys_addr_t size, phys_addr_t align)
|
|
{
|
|
phys_addr_t phys;
|
|
|
|
BUG_ON(!arm_memblock_steal_permitted);
|
|
|
|
phys = memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ANYWHERE);
|
|
memblock_free(phys, size);
|
|
memblock_remove(phys, size);
|
|
|
|
return phys;
|
|
}
|
|
|
|
static void __init arm_initrd_init(void)
|
|
{
|
|
#ifdef CONFIG_BLK_DEV_INITRD
|
|
phys_addr_t start;
|
|
unsigned long size;
|
|
|
|
/* FDT scan will populate initrd_start */
|
|
if (initrd_start && !phys_initrd_size) {
|
|
phys_initrd_start = __virt_to_phys(initrd_start);
|
|
phys_initrd_size = initrd_end - initrd_start;
|
|
}
|
|
|
|
initrd_start = initrd_end = 0;
|
|
|
|
if (!phys_initrd_size)
|
|
return;
|
|
|
|
/*
|
|
* Round the memory region to page boundaries as per free_initrd_mem()
|
|
* This allows us to detect whether the pages overlapping the initrd
|
|
* are in use, but more importantly, reserves the entire set of pages
|
|
* as we don't want these pages allocated for other purposes.
|
|
*/
|
|
start = round_down(phys_initrd_start, PAGE_SIZE);
|
|
size = phys_initrd_size + (phys_initrd_start - start);
|
|
size = round_up(size, PAGE_SIZE);
|
|
|
|
if (!memblock_is_region_memory(start, size)) {
|
|
pr_err("INITRD: 0x%08llx+0x%08lx is not a memory region - disabling initrd\n",
|
|
(u64)start, size);
|
|
return;
|
|
}
|
|
|
|
if (memblock_is_region_reserved(start, size)) {
|
|
pr_err("INITRD: 0x%08llx+0x%08lx overlaps in-use memory region - disabling initrd\n",
|
|
(u64)start, size);
|
|
return;
|
|
}
|
|
|
|
memblock_reserve(start, size);
|
|
|
|
/* Now convert initrd to virtual addresses */
|
|
initrd_start = __phys_to_virt(phys_initrd_start);
|
|
initrd_end = initrd_start + phys_initrd_size;
|
|
#endif
|
|
}
|
|
|
|
void __init arm_memblock_init(const struct machine_desc *mdesc)
|
|
{
|
|
/* Register the kernel text, kernel data and initrd with memblock. */
|
|
memblock_reserve(__pa(KERNEL_START), KERNEL_END - KERNEL_START);
|
|
|
|
arm_initrd_init();
|
|
|
|
arm_mm_memblock_reserve();
|
|
|
|
/* reserve any platform specific memblock areas */
|
|
if (mdesc->reserve)
|
|
mdesc->reserve();
|
|
|
|
early_init_fdt_reserve_self();
|
|
early_init_fdt_scan_reserved_mem();
|
|
|
|
/* reserve memory for DMA contiguous allocations */
|
|
dma_contiguous_reserve(arm_dma_limit);
|
|
|
|
arm_memblock_steal_permitted = false;
|
|
memblock_dump_all();
|
|
}
|
|
|
|
void __init bootmem_init(void)
|
|
{
|
|
unsigned long min, max_low, max_high;
|
|
|
|
memblock_allow_resize();
|
|
max_low = max_high = 0;
|
|
|
|
find_limits(&min, &max_low, &max_high);
|
|
|
|
early_memtest((phys_addr_t)min << PAGE_SHIFT,
|
|
(phys_addr_t)max_low << PAGE_SHIFT);
|
|
|
|
/*
|
|
* Sparsemem tries to allocate bootmem in memory_present(),
|
|
* so must be done after the fixed reservations
|
|
*/
|
|
arm_memory_present();
|
|
|
|
/*
|
|
* sparse_init() needs the bootmem allocator up and running.
|
|
*/
|
|
sparse_init();
|
|
|
|
/*
|
|
* Now free the memory - free_area_init_node needs
|
|
* the sparse mem_map arrays initialized by sparse_init()
|
|
* for memmap_init_zone(), otherwise all PFNs are invalid.
|
|
*/
|
|
zone_sizes_init(min, max_low, max_high);
|
|
|
|
/*
|
|
* This doesn't seem to be used by the Linux memory manager any
|
|
* more, but is used by ll_rw_block. If we can get rid of it, we
|
|
* also get rid of some of the stuff above as well.
|
|
*/
|
|
min_low_pfn = min;
|
|
max_low_pfn = max_low;
|
|
max_pfn = max_high;
|
|
}
|
|
|
|
/*
|
|
* Poison init memory with an undefined instruction (ARM) or a branch to an
|
|
* undefined instruction (Thumb).
|
|
*/
|
|
static inline void poison_init_mem(void *s, size_t count)
|
|
{
|
|
u32 *p = (u32 *)s;
|
|
for (; count != 0; count -= 4)
|
|
*p++ = 0xe7fddef0;
|
|
}
|
|
|
|
static inline void
|
|
free_memmap(unsigned long start_pfn, unsigned long end_pfn)
|
|
{
|
|
struct page *start_pg, *end_pg;
|
|
phys_addr_t pg, pgend;
|
|
|
|
/*
|
|
* Convert start_pfn/end_pfn to a struct page pointer.
|
|
*/
|
|
start_pg = pfn_to_page(start_pfn - 1) + 1;
|
|
end_pg = pfn_to_page(end_pfn - 1) + 1;
|
|
|
|
/*
|
|
* Convert to physical addresses, and
|
|
* round start upwards and end downwards.
|
|
*/
|
|
pg = PAGE_ALIGN(__pa(start_pg));
|
|
pgend = __pa(end_pg) & PAGE_MASK;
|
|
|
|
/*
|
|
* If there are free pages between these,
|
|
* free the section of the memmap array.
|
|
*/
|
|
if (pg < pgend)
|
|
memblock_free_early(pg, pgend - pg);
|
|
}
|
|
|
|
/*
|
|
* The mem_map array can get very big. Free the unused area of the memory map.
|
|
*/
|
|
static void __init free_unused_memmap(void)
|
|
{
|
|
unsigned long start, prev_end = 0;
|
|
struct memblock_region *reg;
|
|
|
|
/*
|
|
* This relies on each bank being in address order.
|
|
* The banks are sorted previously in bootmem_init().
|
|
*/
|
|
for_each_memblock(memory, reg) {
|
|
start = memblock_region_memory_base_pfn(reg);
|
|
|
|
#ifdef CONFIG_SPARSEMEM
|
|
/*
|
|
* Take care not to free memmap entries that don't exist
|
|
* due to SPARSEMEM sections which aren't present.
|
|
*/
|
|
start = min(start,
|
|
ALIGN(prev_end, PAGES_PER_SECTION));
|
|
#else
|
|
/*
|
|
* Align down here since the VM subsystem insists that the
|
|
* memmap entries are valid from the bank start aligned to
|
|
* MAX_ORDER_NR_PAGES.
|
|
*/
|
|
start = round_down(start, MAX_ORDER_NR_PAGES);
|
|
#endif
|
|
/*
|
|
* If we had a previous bank, and there is a space
|
|
* between the current bank and the previous, free it.
|
|
*/
|
|
if (prev_end && prev_end < start)
|
|
free_memmap(prev_end, start);
|
|
|
|
/*
|
|
* Align up here since the VM subsystem insists that the
|
|
* memmap entries are valid from the bank end aligned to
|
|
* MAX_ORDER_NR_PAGES.
|
|
*/
|
|
prev_end = ALIGN(memblock_region_memory_end_pfn(reg),
|
|
MAX_ORDER_NR_PAGES);
|
|
}
|
|
|
|
#ifdef CONFIG_SPARSEMEM
|
|
if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION))
|
|
free_memmap(prev_end,
|
|
ALIGN(prev_end, PAGES_PER_SECTION));
|
|
#endif
|
|
}
|
|
|
|
#ifdef CONFIG_HIGHMEM
|
|
static inline void free_area_high(unsigned long pfn, unsigned long end)
|
|
{
|
|
for (; pfn < end; pfn++)
|
|
free_highmem_page(pfn_to_page(pfn));
|
|
}
|
|
#endif
|
|
|
|
static void __init free_highpages(void)
|
|
{
|
|
#ifdef CONFIG_HIGHMEM
|
|
unsigned long max_low = max_low_pfn;
|
|
struct memblock_region *mem, *res;
|
|
|
|
/* set highmem page free */
|
|
for_each_memblock(memory, mem) {
|
|
unsigned long start = memblock_region_memory_base_pfn(mem);
|
|
unsigned long end = memblock_region_memory_end_pfn(mem);
|
|
|
|
/* Ignore complete lowmem entries */
|
|
if (end <= max_low)
|
|
continue;
|
|
|
|
if (memblock_is_nomap(mem))
|
|
continue;
|
|
|
|
/* Truncate partial highmem entries */
|
|
if (start < max_low)
|
|
start = max_low;
|
|
|
|
/* Find and exclude any reserved regions */
|
|
for_each_memblock(reserved, res) {
|
|
unsigned long res_start, res_end;
|
|
|
|
res_start = memblock_region_reserved_base_pfn(res);
|
|
res_end = memblock_region_reserved_end_pfn(res);
|
|
|
|
if (res_end < start)
|
|
continue;
|
|
if (res_start < start)
|
|
res_start = start;
|
|
if (res_start > end)
|
|
res_start = end;
|
|
if (res_end > end)
|
|
res_end = end;
|
|
if (res_start != start)
|
|
free_area_high(start, res_start);
|
|
start = res_end;
|
|
if (start == end)
|
|
break;
|
|
}
|
|
|
|
/* And now free anything which remains */
|
|
if (start < end)
|
|
free_area_high(start, end);
|
|
}
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* mem_init() marks the free areas in the mem_map and tells us how much
|
|
* memory is free. This is done after various parts of the system have
|
|
* claimed their memory after the kernel image.
|
|
*/
|
|
void __init mem_init(void)
|
|
{
|
|
#ifdef CONFIG_HAVE_TCM
|
|
/* These pointers are filled in on TCM detection */
|
|
extern u32 dtcm_end;
|
|
extern u32 itcm_end;
|
|
#endif
|
|
|
|
set_max_mapnr(pfn_to_page(max_pfn) - mem_map);
|
|
|
|
/* this will put all unused low memory onto the freelists */
|
|
free_unused_memmap();
|
|
free_all_bootmem();
|
|
|
|
#ifdef CONFIG_SA1111
|
|
/* now that our DMA memory is actually so designated, we can free it */
|
|
free_reserved_area(__va(PHYS_OFFSET), swapper_pg_dir, -1, NULL);
|
|
#endif
|
|
|
|
free_highpages();
|
|
|
|
mem_init_print_info(NULL);
|
|
|
|
#define MLK(b, t) b, t, ((t) - (b)) >> 10
|
|
#define MLM(b, t) b, t, ((t) - (b)) >> 20
|
|
#define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
|
|
|
|
pr_notice("Virtual kernel memory layout:\n"
|
|
" vector : 0x%08lx - 0x%08lx (%4ld kB)\n"
|
|
#ifdef CONFIG_HAVE_TCM
|
|
" DTCM : 0x%08lx - 0x%08lx (%4ld kB)\n"
|
|
" ITCM : 0x%08lx - 0x%08lx (%4ld kB)\n"
|
|
#endif
|
|
" fixmap : 0x%08lx - 0x%08lx (%4ld kB)\n"
|
|
" vmalloc : 0x%08lx - 0x%08lx (%4ld MB)\n"
|
|
" lowmem : 0x%08lx - 0x%08lx (%4ld MB)\n"
|
|
#ifdef CONFIG_HIGHMEM
|
|
" pkmap : 0x%08lx - 0x%08lx (%4ld MB)\n"
|
|
#endif
|
|
#ifdef CONFIG_MODULES
|
|
" modules : 0x%08lx - 0x%08lx (%4ld MB)\n"
|
|
#endif
|
|
" .text : 0x%p" " - 0x%p" " (%4td kB)\n"
|
|
" .init : 0x%p" " - 0x%p" " (%4td kB)\n"
|
|
" .data : 0x%p" " - 0x%p" " (%4td kB)\n"
|
|
" .bss : 0x%p" " - 0x%p" " (%4td kB)\n",
|
|
|
|
MLK(VECTORS_BASE, VECTORS_BASE + PAGE_SIZE),
|
|
#ifdef CONFIG_HAVE_TCM
|
|
MLK(DTCM_OFFSET, (unsigned long) dtcm_end),
|
|
MLK(ITCM_OFFSET, (unsigned long) itcm_end),
|
|
#endif
|
|
MLK(FIXADDR_START, FIXADDR_END),
|
|
MLM(VMALLOC_START, VMALLOC_END),
|
|
MLM(PAGE_OFFSET, (unsigned long)high_memory),
|
|
#ifdef CONFIG_HIGHMEM
|
|
MLM(PKMAP_BASE, (PKMAP_BASE) + (LAST_PKMAP) *
|
|
(PAGE_SIZE)),
|
|
#endif
|
|
#ifdef CONFIG_MODULES
|
|
MLM(MODULES_VADDR, MODULES_END),
|
|
#endif
|
|
|
|
MLK_ROUNDUP(_text, _etext),
|
|
MLK_ROUNDUP(__init_begin, __init_end),
|
|
MLK_ROUNDUP(_sdata, _edata),
|
|
MLK_ROUNDUP(__bss_start, __bss_stop));
|
|
|
|
#undef MLK
|
|
#undef MLM
|
|
#undef MLK_ROUNDUP
|
|
|
|
/*
|
|
* Check boundaries twice: Some fundamental inconsistencies can
|
|
* be detected at build time already.
|
|
*/
|
|
#ifdef CONFIG_MMU
|
|
BUILD_BUG_ON(TASK_SIZE > MODULES_VADDR);
|
|
BUG_ON(TASK_SIZE > MODULES_VADDR);
|
|
#endif
|
|
|
|
#ifdef CONFIG_HIGHMEM
|
|
BUILD_BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET);
|
|
BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET);
|
|
#endif
|
|
}
|
|
|
|
#ifdef CONFIG_STRICT_KERNEL_RWX
|
|
struct section_perm {
|
|
const char *name;
|
|
unsigned long start;
|
|
unsigned long end;
|
|
pmdval_t mask;
|
|
pmdval_t prot;
|
|
pmdval_t clear;
|
|
};
|
|
|
|
/* First section-aligned location at or after __start_rodata. */
|
|
extern char __start_rodata_section_aligned[];
|
|
|
|
static struct section_perm nx_perms[] = {
|
|
/* Make pages tables, etc before _stext RW (set NX). */
|
|
{
|
|
.name = "pre-text NX",
|
|
.start = PAGE_OFFSET,
|
|
.end = (unsigned long)_stext,
|
|
.mask = ~PMD_SECT_XN,
|
|
.prot = PMD_SECT_XN,
|
|
},
|
|
/* Make init RW (set NX). */
|
|
{
|
|
.name = "init NX",
|
|
.start = (unsigned long)__init_begin,
|
|
.end = (unsigned long)_sdata,
|
|
.mask = ~PMD_SECT_XN,
|
|
.prot = PMD_SECT_XN,
|
|
},
|
|
/* Make rodata NX (set RO in ro_perms below). */
|
|
{
|
|
.name = "rodata NX",
|
|
.start = (unsigned long)__start_rodata_section_aligned,
|
|
.end = (unsigned long)__init_begin,
|
|
.mask = ~PMD_SECT_XN,
|
|
.prot = PMD_SECT_XN,
|
|
},
|
|
};
|
|
|
|
static struct section_perm ro_perms[] = {
|
|
/* Make kernel code and rodata RX (set RO). */
|
|
{
|
|
.name = "text/rodata RO",
|
|
.start = (unsigned long)_stext,
|
|
.end = (unsigned long)__init_begin,
|
|
#ifdef CONFIG_ARM_LPAE
|
|
.mask = ~(L_PMD_SECT_RDONLY | PMD_SECT_AP2),
|
|
.prot = L_PMD_SECT_RDONLY | PMD_SECT_AP2,
|
|
#else
|
|
.mask = ~(PMD_SECT_APX | PMD_SECT_AP_WRITE),
|
|
.prot = PMD_SECT_APX | PMD_SECT_AP_WRITE,
|
|
.clear = PMD_SECT_AP_WRITE,
|
|
#endif
|
|
},
|
|
};
|
|
|
|
/*
|
|
* Updates section permissions only for the current mm (sections are
|
|
* copied into each mm). During startup, this is the init_mm. Is only
|
|
* safe to be called with preemption disabled, as under stop_machine().
|
|
*/
|
|
static inline void section_update(unsigned long addr, pmdval_t mask,
|
|
pmdval_t prot, struct mm_struct *mm)
|
|
{
|
|
pmd_t *pmd;
|
|
|
|
pmd = pmd_offset(pud_offset(pgd_offset(mm, addr), addr), addr);
|
|
|
|
#ifdef CONFIG_ARM_LPAE
|
|
pmd[0] = __pmd((pmd_val(pmd[0]) & mask) | prot);
|
|
#else
|
|
if (addr & SECTION_SIZE)
|
|
pmd[1] = __pmd((pmd_val(pmd[1]) & mask) | prot);
|
|
else
|
|
pmd[0] = __pmd((pmd_val(pmd[0]) & mask) | prot);
|
|
#endif
|
|
flush_pmd_entry(pmd);
|
|
local_flush_tlb_kernel_range(addr, addr + SECTION_SIZE);
|
|
}
|
|
|
|
/* Make sure extended page tables are in use. */
|
|
static inline bool arch_has_strict_perms(void)
|
|
{
|
|
if (cpu_architecture() < CPU_ARCH_ARMv6)
|
|
return false;
|
|
|
|
return !!(get_cr() & CR_XP);
|
|
}
|
|
|
|
void set_section_perms(struct section_perm *perms, int n, bool set,
|
|
struct mm_struct *mm)
|
|
{
|
|
size_t i;
|
|
unsigned long addr;
|
|
|
|
if (!arch_has_strict_perms())
|
|
return;
|
|
|
|
for (i = 0; i < n; i++) {
|
|
if (!IS_ALIGNED(perms[i].start, SECTION_SIZE) ||
|
|
!IS_ALIGNED(perms[i].end, SECTION_SIZE)) {
|
|
pr_err("BUG: %s section %lx-%lx not aligned to %lx\n",
|
|
perms[i].name, perms[i].start, perms[i].end,
|
|
SECTION_SIZE);
|
|
continue;
|
|
}
|
|
|
|
for (addr = perms[i].start;
|
|
addr < perms[i].end;
|
|
addr += SECTION_SIZE)
|
|
section_update(addr, perms[i].mask,
|
|
set ? perms[i].prot : perms[i].clear, mm);
|
|
}
|
|
|
|
}
|
|
|
|
/**
|
|
* update_sections_early intended to be called only through stop_machine
|
|
* framework and executed by only one CPU while all other CPUs will spin and
|
|
* wait, so no locking is required in this function.
|
|
*/
|
|
static void update_sections_early(struct section_perm perms[], int n)
|
|
{
|
|
struct task_struct *t, *s;
|
|
|
|
for_each_process(t) {
|
|
if (t->flags & PF_KTHREAD)
|
|
continue;
|
|
for_each_thread(t, s)
|
|
set_section_perms(perms, n, true, s->mm);
|
|
}
|
|
set_section_perms(perms, n, true, current->active_mm);
|
|
set_section_perms(perms, n, true, &init_mm);
|
|
}
|
|
|
|
static int __fix_kernmem_perms(void *unused)
|
|
{
|
|
update_sections_early(nx_perms, ARRAY_SIZE(nx_perms));
|
|
return 0;
|
|
}
|
|
|
|
static void fix_kernmem_perms(void)
|
|
{
|
|
stop_machine(__fix_kernmem_perms, NULL, NULL);
|
|
}
|
|
|
|
static int __mark_rodata_ro(void *unused)
|
|
{
|
|
update_sections_early(ro_perms, ARRAY_SIZE(ro_perms));
|
|
return 0;
|
|
}
|
|
|
|
static int kernel_set_to_readonly __read_mostly;
|
|
|
|
void mark_rodata_ro(void)
|
|
{
|
|
kernel_set_to_readonly = 1;
|
|
stop_machine(__mark_rodata_ro, NULL, NULL);
|
|
debug_checkwx();
|
|
}
|
|
|
|
void set_kernel_text_rw(void)
|
|
{
|
|
if (!kernel_set_to_readonly)
|
|
return;
|
|
|
|
set_section_perms(ro_perms, ARRAY_SIZE(ro_perms), false,
|
|
current->active_mm);
|
|
}
|
|
|
|
void set_kernel_text_ro(void)
|
|
{
|
|
if (!kernel_set_to_readonly)
|
|
return;
|
|
|
|
set_section_perms(ro_perms, ARRAY_SIZE(ro_perms), true,
|
|
current->active_mm);
|
|
}
|
|
|
|
#else
|
|
static inline void fix_kernmem_perms(void) { }
|
|
#endif /* CONFIG_STRICT_KERNEL_RWX */
|
|
|
|
void free_initmem(void)
|
|
{
|
|
fix_kernmem_perms();
|
|
|
|
poison_init_mem(__init_begin, __init_end - __init_begin);
|
|
if (!machine_is_integrator() && !machine_is_cintegrator())
|
|
free_initmem_default(-1);
|
|
}
|
|
|
|
#ifdef CONFIG_BLK_DEV_INITRD
|
|
|
|
static int keep_initrd;
|
|
|
|
void free_initrd_mem(unsigned long start, unsigned long end)
|
|
{
|
|
if (!keep_initrd) {
|
|
if (start == initrd_start)
|
|
start = round_down(start, PAGE_SIZE);
|
|
if (end == initrd_end)
|
|
end = round_up(end, PAGE_SIZE);
|
|
|
|
poison_init_mem((void *)start, PAGE_ALIGN(end) - start);
|
|
free_reserved_area((void *)start, (void *)end, -1, "initrd");
|
|
}
|
|
}
|
|
|
|
static int __init keepinitrd_setup(char *__unused)
|
|
{
|
|
keep_initrd = 1;
|
|
return 1;
|
|
}
|
|
|
|
__setup("keepinitrd", keepinitrd_setup);
|
|
#endif
|