path: root/arch/x86/mm/init_64.c

/*
 *  linux/arch/x86_64/mm/init.c
 *
 *  Copyright (C) 1995  Linus Torvalds
 *  Copyright (C) 2000  Pavel Machek <pavel@ucw.cz>
 *  Copyright (C) 2002,2003 Andi Kleen <ak@suse.de>
 */

#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/ptrace.h>
#include <linux/mman.h>
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/smp.h>
#include <linux/init.h>
#include <linux/initrd.h>
#include <linux/pagemap.h>
#include <linux/memblock.h>
#include <linux/proc_fs.h>
#include <linux/pci.h>
#include <linux/pfn.h>
#include <linux/poison.h>
#include <linux/dma-mapping.h>
#include <linux/memory.h>
#include <linux/memory_hotplug.h>
#include <linux/memremap.h>
#include <linux/nmi.h>
#include <linux/gfp.h>
#include <linux/kcore.h>

#include <asm/processor.h>
#include <asm/bios_ebda.h>
#include <linux/uaccess.h>
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
#include <asm/dma.h>
#include <asm/fixmap.h>
#include <asm/e820/api.h>
#include <asm/apic.h>
#include <asm/tlb.h>
#include <asm/mmu_context.h>
#include <asm/proto.h>
#include <asm/smp.h>
#include <asm/sections.h>
#include <asm/kdebug.h>
#include <asm/numa.h>
#include <asm/set_memory.h>
#include <asm/init.h>
#include <asm/uv/uv.h>
#include <asm/setup.h>

#include "mm_internal.h"

#include "ident_map.c"

#define DEFINE_POPULATE(fname, type1, type2, init)		\
static inline void fname##_init(struct mm_struct *mm,		\
		type1##_t *arg1, type2##_t *arg2, bool init)	\
{								\
	if (init)						\
		fname##_safe(mm, arg1, arg2);			\
	else							\
		fname(mm, arg1, arg2);				\
}

DEFINE_POPULATE(p4d_populate, p4d, pud, init)
DEFINE_POPULATE(pgd_populate, pgd, p4d, init)
DEFINE_POPULATE(pud_populate, pud, pmd, init)
DEFINE_POPULATE(pmd_populate_kernel, pmd, pte, init)

#define DEFINE_ENTRY(type1, type2, init)			\
static inline void set_##type1##_init(type1##_t *arg1,		\
			type2##_t arg2, bool init)		\
{								\
	if (init)						\
		set_##type1##_safe(arg1, arg2);			\
	else							\
		set_##type1(arg1, arg2);			\
}

DEFINE_ENTRY(p4d, p4d, init)
DEFINE_ENTRY(pud, pud, init)
DEFINE_ENTRY(pmd, pmd, init)
DEFINE_ENTRY(pte, pte, init)


/*
 * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the
 * physical space so we can cache the place of the first one and move
 * around without checking the pgd every time.
 */

/* Bits supported by the hardware: */
pteval_t __supported_pte_mask __read_mostly = ~0;
/* Bits allowed in normal kernel mappings: */
pteval_t __default_kernel_pte_mask __read_mostly = ~0;
EXPORT_SYMBOL_GPL(__supported_pte_mask);
/* Used in PAGE_KERNEL_* macros which are reasonably used out-of-tree: */
EXPORT_SYMBOL(__default_kernel_pte_mask);

int force_personality32;

/*
 * noexec32=on|off
 * Control non executable heap for 32bit processes.
 * To control the stack too use noexec=off
 *
 * on	PROT_READ does not imply PROT_EXEC for 32-bit processes (default)
 * off	PROT_READ implies PROT_EXEC
 */
static int __init nonx32_setup(char *str)
{
	if (!strcmp(str, "on"))
		force_personality32 &= ~READ_IMPLIES_EXEC;
	else if (!strcmp(str, "off"))
		force_personality32 |= READ_IMPLIES_EXEC;
	return 1;
}
__setup("noexec32=", nonx32_setup);

static void sync_global_pgds_l5(unsigned long start, unsigned long end)
{
	unsigned long addr;

	for (addr = start; addr <= end; addr = ALIGN(addr + 1, PGDIR_SIZE)) {
		const pgd_t *pgd_ref = pgd_offset_k(addr);
		struct page *page;

		/* Check for overflow */
		if (addr < start)
			break;

		if (pgd_none(*pgd_ref))
			continue;

		spin_lock(&pgd_lock);
		list_for_each_entry(page, &pgd_list, lru) {
			pgd_t *pgd;
			spinlock_t *pgt_lock;

			pgd = (pgd_t *)page_address(page) + pgd_index(addr);
			/* the pgt_lock only for Xen */
			pgt_lock = &pgd_page_get_mm(page)->page_table_lock;
			spin_lock(pgt_lock);

			if (!pgd_none(*pgd_ref) && !pgd_none(*pgd))
				BUG_ON(pgd_page_vaddr(*pgd) != pgd_page_vaddr(*pgd_ref));

			if (pgd_none(*pgd))
				set_pgd(pgd, *pgd_ref);

			spin_unlock(pgt_lock);
		}
		spin_unlock(&pgd_lock);